Fix write-over-delete failing for the very first entry in dirty_db

New features:

- Data and metadata checksums!
  - Metadata checksums are always used with new disk format
  - Data checksums can be turned on with --data_csum_type crc32c for new OSDs
  - Checksum block size can be configured
  - inmemory_metadata now also affects keeping checksums in memory
- Linux page cache I/O caching support which can be enabled separately for
  data, metadata (including checksums) and journal (O_SYNC instead of O_DIRECT)
- Details [here](https://git.yourcmc.ru/vitalif/vitastor/src/branch/master/docs/config/layout-osd.en.md#data_csum_type)
- Backwards compatibility is preserved, you can use new OSDs with old disks

Release also includes bug fixes from [0.9.6](https://git.yourcmc.ru/vitalif/vitastor/releases/tag/v0.9.6).

0.9.6 is moved to "-oldstable" repositories and will be available for some additional time.

.gitea/workflows/test.Dockerfile

@@ -10,6 +10,9 @@ RUN set -e -x; \
     ln -s /root/fio-build/fio-*/ ./fio; \
     ln -s /root/qemu-build/qemu-*/ ./qemu; \
     ls /usr/include/linux/raw.h || cp ./debian/raw.h /usr/include/linux/raw.h; \
+    cd mon; \
+    npm install; \
+    cd ..; \
     mkdir build; \
     cd build; \
     cmake .. -DWITH_ASAN=yes -DWITH_QEMU=yes; \

.gitea/workflows/test.yml

@@ -190,24 +190,6 @@ jobs:
           echo ""
         done
 
-  test_failure_domain:
-    runs-on: ubuntu-latest
-    needs: build
-    container: ${{env.TEST_IMAGE}}:${{github.sha}}
-    steps:
-    - name: Run test
-      id: test
-      timeout-minutes: 3
-      run: /root/vitastor/tests/test_failure_domain.sh
-    - name: Print logs
-      if: always() && steps.test.outcome == 'failure'
-      run: |
-        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
-          echo "-------- $i --------"
-          cat $i
-          echo ""
-        done
-
   test_interrupted_rebalance:
     runs-on: ubuntu-latest
     needs: build
@@ -280,6 +262,60 @@ jobs:
           echo ""
         done
 
+  test_failure_domain:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_failure_domain.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_snapshot:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_snapshot.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_snapshot_ec:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: SCHEME=ec /root/vitastor/tests/test_snapshot.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
   test_minsize_1:
     runs-on: ubuntu-latest
     needs: build
@@ -316,6 +352,114 @@ jobs:
           echo ""
         done
 
+  test_rm:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_rm.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_snapshot_chain:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_snapshot_chain.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_snapshot_chain_ec:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: SCHEME=ec /root/vitastor/tests/test_snapshot_chain.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_snapshot_down:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_snapshot_down.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_snapshot_down_ec:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: SCHEME=ec /root/vitastor/tests/test_snapshot_down.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_splitbrain:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 3
+      run: /root/vitastor/tests/test_splitbrain.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
   test_rebalance_verify:
     runs-on: ubuntu-latest
     needs: build
@@ -388,78 +532,6 @@ jobs:
           echo ""
         done
 
-  test_rm:
-    runs-on: ubuntu-latest
-    needs: build
-    container: ${{env.TEST_IMAGE}}:${{github.sha}}
-    steps:
-    - name: Run test
-      id: test
-      timeout-minutes: 3
-      run: /root/vitastor/tests/test_rm.sh
-    - name: Print logs
-      if: always() && steps.test.outcome == 'failure'
-      run: |
-        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
-          echo "-------- $i --------"
-          cat $i
-          echo ""
-        done
-
-  test_snapshot:
-    runs-on: ubuntu-latest
-    needs: build
-    container: ${{env.TEST_IMAGE}}:${{github.sha}}
-    steps:
-    - name: Run test
-      id: test
-      timeout-minutes: 3
-      run: /root/vitastor/tests/test_snapshot.sh
-    - name: Print logs
-      if: always() && steps.test.outcome == 'failure'
-      run: |
-        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
-          echo "-------- $i --------"
-          cat $i
-          echo ""
-        done
-
-  test_snapshot_ec:
-    runs-on: ubuntu-latest
-    needs: build
-    container: ${{env.TEST_IMAGE}}:${{github.sha}}
-    steps:
-    - name: Run test
-      id: test
-      timeout-minutes: 3
-      run: SCHEME=ec /root/vitastor/tests/test_snapshot.sh
-    - name: Print logs
-      if: always() && steps.test.outcome == 'failure'
-      run: |
-        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
-          echo "-------- $i --------"
-          cat $i
-          echo ""
-        done
-
-  test_splitbrain:
-    runs-on: ubuntu-latest
-    needs: build
-    container: ${{env.TEST_IMAGE}}:${{github.sha}}
-    steps:
-    - name: Run test
-      id: test
-      timeout-minutes: 3
-      run: /root/vitastor/tests/test_splitbrain.sh
-    - name: Print logs
-      if: always() && steps.test.outcome == 'failure'
-      run: |
-        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
-          echo "-------- $i --------"
-          cat $i
-          echo ""
-        done
-
   test_write:
     runs-on: ubuntu-latest
     needs: build
@@ -550,6 +622,114 @@ jobs:
           echo ""
         done
 
+  test_heal_csum_32k_dmj:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 10
+      run: TEST_NAME=csum_32k_dmj OSD_ARGS="--data_csum_type crc32c --csum_block_size 32k --inmemory_metadata false --inmemory_journal false" OFFSET_ARGS=$OSD_ARGS /root/vitastor/tests/test_heal.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_heal_csum_32k_dj:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 10
+      run: TEST_NAME=csum_32k_dj  OSD_ARGS="--data_csum_type crc32c --csum_block_size 32k --inmemory_journal false" OFFSET_ARGS=$OSD_ARGS /root/vitastor/tests/test_heal.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_heal_csum_32k:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 10
+      run: TEST_NAME=csum_32k     OSD_ARGS="--data_csum_type crc32c --csum_block_size 32k" OFFSET_ARGS=$OSD_ARGS /root/vitastor/tests/test_heal.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_heal_csum_4k_dmj:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 10
+      run: TEST_NAME=csum_4k_dmj  OSD_ARGS="--data_csum_type crc32c --inmemory_metadata false --inmemory_journal false" OFFSET_ARGS=$OSD_ARGS /root/vitastor/tests/test_heal.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_heal_csum_4k_dj:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 10
+      run: TEST_NAME=csum_4k_dj   OSD_ARGS="--data_csum_type crc32c --inmemory_journal false" OFFSET_ARGS=$OSD_ARGS /root/vitastor/tests/test_heal.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
+  test_heal_csum_4k:
+    runs-on: ubuntu-latest
+    needs: build
+    container: ${{env.TEST_IMAGE}}:${{github.sha}}
+    steps:
+    - name: Run test
+      id: test
+      timeout-minutes: 10
+      run: TEST_NAME=csum_4k      OSD_ARGS="--data_csum_type crc32c" OFFSET_ARGS=$OSD_ARGS /root/vitastor/tests/test_heal.sh
+    - name: Print logs
+      if: always() && steps.test.outcome == 'failure'
+      run: |
+        for i in /root/vitastor/testdata/*.log /root/vitastor/testdata/*.txt; do
+          echo "-------- $i --------"
+          cat $i
+          echo ""
+        done
+
   test_scrub:
     runs-on: ubuntu-latest
     needs: build

.gitea/workflows/tests-to-yaml.pl

@@ -7,7 +7,8 @@ for my $line (<>)
     if ($line =~ /\.\/(test_[^\.]+)/s)
     {
         chomp $line;
-        my $test_name = $1;
+        my $base_name = $1;
+        my $test_name = $base_name;
         my $timeout = 3;
         if ($test_name eq 'test_etcd_fail' || $test_name eq 'test_heal' || $test_name eq 'test_add_osd' ||
             $test_name eq 'test_interrupted_rebalance' || $test_name eq 'test_rebalance_verify')
@@ -16,7 +17,12 @@ for my $line (<>)
         }
         while ($line =~ /([^\s=]+)=(\S+)/gs)
         {
-            if ($1 eq 'SCHEME' && $2 eq 'ec')
+            if ($1 eq 'TEST_NAME')
+            {
+                $test_name = $base_name.'_'.$2;
+                last;
+            }
+            elsif ($1 eq 'SCHEME' && $2 eq 'ec')
             {
                 $test_name .= '_ec';
             }

CMakeLists.txt

@@ -2,6 +2,6 @@ cmake_minimum_required(VERSION 2.8.12)
 
 project(vitastor)
 
-set(VERSION "0.9.2")
+set(VERSION "1.0.0")
 
 add_subdirectory(src)

README-ru.md

@@ -15,7 +15,7 @@ Vitastor архитектурно похож на Ceph, что означает
 и автоматическое распределение данных по любому числу дисков любого размера с настраиваемыми схемами
 избыточности - репликацией или с произвольными кодами коррекции ошибок.
 
-Vitastor нацелен на SSD и SSD+HDD кластеры с как минимум 10 Гбит/с сетью, поддерживает
+Vitastor нацелен в первую очередь на SSD и SSD+HDD кластеры с как минимум 10 Гбит/с сетью, поддерживает
 TCP и RDMA и на хорошем железе может достигать задержки 4 КБ чтения и записи на уровне ~0.1 мс,
 что примерно в 10 раз быстрее, чем Ceph и другие популярные программные СХД.
 

README.md

@@ -14,8 +14,8 @@ Vitastor is architecturally similar to Ceph which means strong consistency,
 primary-replication, symmetric clustering and automatic data distribution over any
 number of drives of any size with configurable redundancy (replication or erasure codes/XOR).
 
-Vitastor targets SSD and SSD+HDD clusters with at least 10 Gbit/s network, supports
-TCP and RDMA and may achieve 4 KB read and write latency as low as ~0.1 ms
+Vitastor targets primarily SSD and SSD+HDD clusters with at least 10 Gbit/s network,
+supports TCP and RDMA and may achieve 4 KB read and write latency as low as ~0.1 ms
 with proper hardware which is ~10 times faster than other popular SDS's like Ceph
 or internal systems of public clouds.
 

csi/Makefile

@@ -1,4 +1,4 @@
-VERSION ?= v0.9.2
+VERSION ?= v1.0.0
 
 all: build push
 

csi/deploy/004-csi-nodeplugin.yaml

@@ -49,7 +49,7 @@ spec:
             capabilities:
               add: ["SYS_ADMIN"]
             allowPrivilegeEscalation: true
-          image: vitalif/vitastor-csi:v0.9.2
+          image: vitalif/vitastor-csi:v1.0.0
           args:
             - "--node=$(NODE_ID)"
             - "--endpoint=$(CSI_ENDPOINT)"

csi/deploy/007-csi-provisioner.yaml

@@ -116,7 +116,7 @@ spec:
             privileged: true
             capabilities:
               add: ["SYS_ADMIN"]
-          image: vitalif/vitastor-csi:v0.9.2
+          image: vitalif/vitastor-csi:v1.0.0
           args:
             - "--node=$(NODE_ID)"
             - "--endpoint=$(CSI_ENDPOINT)"

csi/src/config.go

@@ -5,7 +5,7 @@ package vitastor
 
 const (
     vitastorCSIDriverName    = "csi.vitastor.io"
-    vitastorCSIDriverVersion = "0.9.2"
+    vitastorCSIDriverVersion = "1.0.0"
 )
 
 // Config struct fills the parameters of request or user input

debian/build-pve-qemu.sh

@@ -0,0 +1,58 @@
+exit
+
+git clone https://git.yourcmc.ru/vitalif/pve-qemu .
+
+# bookworm
+
+docker run -it -v `pwd`/pve-qemu:/root/pve-qemu --name pve-qemu-bullseye debian:bullseye bash
+
+perl -i -pe 's/Types: deb$/Types: deb deb-src/' /etc/apt/sources.list.d/debian.sources
+echo 'deb [arch=amd64] http://download.proxmox.com/debian/pve bookworm pve-no-subscription' >> /etc/apt/sources.list
+echo 'deb https://vitastor.io/debian bookworm main' >> /etc/apt/sources.list
+echo 'APT::Install-Recommends false;' >> /etc/apt/apt.conf
+echo 'ru_RU UTF-8' >> /etc/locale.gen
+echo 'en_US UTF-8' >> /etc/locale.gen
+apt-get update
+apt-get install wget ca-certificates
+wget https://enterprise.proxmox.com/debian/proxmox-release-bookworm.gpg -O /etc/apt/trusted.gpg.d/proxmox-release-bookworm.gpg
+wget https://vitastor.io/debian/pubkey.gpg -O /etc/apt/trusted.gpg.d/vitastor.gpg
+apt-get update
+apt-get install git devscripts equivs wget mc libjemalloc-dev vitastor-client-dev lintian locales
+mk-build-deps --install ./control
+
+# bullseye
+
+docker run -it -v `pwd`/pve-qemu:/root/pve-qemu --name pve-qemu-bullseye debian:bullseye bash
+
+grep '^deb ' /etc/apt/sources.list | perl -pe 's/^deb /deb-src /' >> /etc/apt/sources.list
+echo 'deb [arch=amd64] http://download.proxmox.com/debian/pve bullseye pve-no-subscription' >> /etc/apt/sources.list
+echo 'deb https://vitastor.io/debian bullseye main' >> /etc/apt/sources.list
+echo 'APT::Install-Recommends false;' >> /etc/apt/apt.conf
+echo 'ru_RU UTF-8' >> /etc/locale.gen
+echo 'en_US UTF-8' >> /etc/locale.gen
+apt-get update
+apt-get install wget
+wget https://enterprise.proxmox.com/debian/proxmox-release-bullseye.gpg -O /etc/apt/trusted.gpg.d/proxmox-release-bullseye.gpg
+wget https://vitastor.io/debian/pubkey.gpg -O /etc/apt/trusted.gpg.d/vitastor.gpg
+apt-get update
+apt-get install git devscripts equivs wget mc libjemalloc-dev vitastor-client-dev lintian locales
+mk-build-deps --install ./control
+
+# buster
+
+docker run -it -v `pwd`/pve-qemu:/root/pve-qemu --name pve-qemu-buster debian:buster bash
+
+grep '^deb ' /etc/apt/sources.list | perl -pe 's/^deb /deb-src /' >> /etc/apt/sources.list
+echo 'deb [arch=amd64] http://download.proxmox.com/debian/pve buster pve-no-subscription' >> /etc/apt/sources.list
+echo 'deb https://vitastor.io/debian buster main' >> /etc/apt/sources.list
+echo 'deb http://deb.debian.org/debian buster-backports main' >> /etc/apt/sources.list
+echo 'APT::Install-Recommends false;' >> /etc/apt/apt.conf
+echo 'ru_RU UTF-8' >> /etc/locale.gen
+echo 'en_US UTF-8' >> /etc/locale.gen
+apt-get update
+apt-get install wget ca-certificates
+wget http://download.proxmox.com/debian/proxmox-ve-release-6.x.gpg -O /etc/apt/trusted.gpg.d/proxmox-ve-release-6.x.gpg
+wget https://vitastor.io/debian/pubkey.gpg -O /etc/apt/trusted.gpg.d/vitastor.gpg
+apt-get update
+apt-get install git devscripts equivs wget mc libjemalloc-dev vitastor-client-dev lintian locales
+mk-build-deps --install ./control

debian/changelog

@@ -1,10 +1,10 @@
-vitastor (0.9.2-1) unstable; urgency=medium
+vitastor (1.0.0-1) unstable; urgency=medium
 
   * Bugfixes
 
  -- Vitaliy Filippov <vitalif@yourcmc.ru>  Fri, 03 Jun 2022 02:09:44 +0300
 
-vitastor (0.9.2-1) unstable; urgency=medium
+vitastor (1.0.0-1) unstable; urgency=medium
 
   * Implement NFS proxy
   * Add documentation

debian/patched-qemu.Dockerfile

@@ -28,13 +28,19 @@ RUN apt-get --download-only source qemu
 
 ADD patches /root/vitastor/patches
 ADD src/qemu_driver.c /root/vitastor/src/qemu_driver.c
+
+#RUN set -e; \
+#    apt-get install -y wget; \
+#    wget -q -O /etc/apt/trusted.gpg.d/vitastor.gpg https://vitastor.io/debian/pubkey.gpg; \
+#    (echo deb http://vitastor.io/debian $REL main > /etc/apt/sources.list.d/vitastor.list); \
+#    (echo "APT::Install-Recommends false;" > /etc/apt/apt.conf) && \
+#    apt-get update; \
+#    apt-get install -y vitastor-client vitastor-client-dev quilt
+
 RUN set -e; \
-    apt-get install -y wget; \
-    wget -q -O /etc/apt/trusted.gpg.d/vitastor.gpg https://vitastor.io/debian/pubkey.gpg; \
-    (echo deb http://vitastor.io/debian $REL main > /etc/apt/sources.list.d/vitastor.list); \
-    (echo "APT::Install-Recommends false;" > /etc/apt/apt.conf) && \
+    dpkg -i /root/packages/vitastor-$REL/vitastor-client_*.deb /root/packages/vitastor-$REL/vitastor-client-dev_*.deb; \
     apt-get update; \
-    apt-get install -y vitastor-client vitastor-client-dev quilt; \
+    apt-get install -y quilt; \
     mkdir -p /root/packages/qemu-$REL; \
     rm -rf /root/packages/qemu-$REL/*; \
     cd /root/packages/qemu-$REL; \
@@ -48,7 +54,7 @@ RUN set -e; \
     quilt add block/vitastor.c; \
     cp /root/vitastor/src/qemu_driver.c block/vitastor.c; \
     quilt refresh; \
-    V=$(head -n1 debian/changelog | perl -pe 's/^.*\((.*?)(~bpo[\d\+]*)?\).*$/$1/')+vitastor1; \
+    V=$(head -n1 debian/changelog | perl -pe 's/^.*\((.*?)(~bpo[\d\+]*)?\).*$/$1/')+vitastor3; \
     DEBEMAIL="Vitaliy Filippov <vitalif@yourcmc.ru>" dch -D $REL -v $V 'Plug Vitastor block driver'; \
     DEB_BUILD_OPTIONS=nocheck dpkg-buildpackage --jobs=auto -sa; \
     rm -rf /root/packages/qemu-$REL/qemu-*/

debian/vitastor.Dockerfile

@@ -35,8 +35,8 @@ RUN set -e -x; \
     mkdir -p /root/packages/vitastor-$REL; \
     rm -rf /root/packages/vitastor-$REL/*; \
     cd /root/packages/vitastor-$REL; \
-    cp -r /root/vitastor vitastor-0.9.2; \
-    cd vitastor-0.9.2; \
+    cp -r /root/vitastor vitastor-1.0.0; \
+    cd vitastor-1.0.0; \
     ln -s /root/fio-build/fio-*/ ./fio; \
     FIO=$(head -n1 fio/debian/changelog | perl -pe 's/^.*\((.*?)\).*$/$1/'); \
     ls /usr/include/linux/raw.h || cp ./debian/raw.h /usr/include/linux/raw.h; \
@@ -49,8 +49,8 @@ RUN set -e -x; \
     rm -rf a b; \
     echo "dep:fio=$FIO" > debian/fio_version; \
     cd /root/packages/vitastor-$REL; \
-    tar --sort=name --mtime='2020-01-01' --owner=0 --group=0 --exclude=debian -cJf vitastor_0.9.2.orig.tar.xz vitastor-0.9.2; \
-    cd vitastor-0.9.2; \
+    tar --sort=name --mtime='2020-01-01' --owner=0 --group=0 --exclude=debian -cJf vitastor_1.0.0.orig.tar.xz vitastor-1.0.0; \
+    cd vitastor-1.0.0; \
     V=$(head -n1 debian/changelog | perl -pe 's/^.*\((.*?)\).*$/$1/'); \
     DEBFULLNAME="Vitaliy Filippov <vitalif@yourcmc.ru>" dch -D $REL -v "$V""$REL" "Rebuild for $REL"; \
     DEB_BUILD_OPTIONS=nocheck dpkg-buildpackage --jobs=auto -sa; \

docs/config.en.md

@@ -21,7 +21,7 @@ Configuration parameters can be set in 3 places:
   mon, fio and QEMU options, OpenStack/Proxmox/etc configuration. The latter
   doesn't allow to set all variables directly, but it allows to override the
   configuration file and set everything you need inside it.
-- OSD superblocks created by [vitastor-disk](../usage/disk.en.md) contain
+- OSD superblocks created by [vitastor-disk](usage/disk.en.md) contain
   primarily disk layout parameters of specific OSDs. In fact, these parameters
   are automatically passed into the command line of vitastor-osd process, so
   they have the same "status" as command-line parameters.

docs/config.ru.md

@@ -23,7 +23,7 @@
   монитора, опциях fio и QEMU, настроек OpenStack, Proxmox и т.п. Последние,
   как правило, не включают полный набор параметров напрямую, но позволяют
   определить путь к файлу конфигурации и задать любые параметры в нём.
-- В суперблоке OSD, записываемом [vitastor-disk](../usage/disk.ru.md) - параметры,
+- В суперблоке OSD, записываемом [vitastor-disk](usage/disk.ru.md) - параметры,
   связанные с дисковым форматом и с этим конкретным OSD. На самом деле,
   при запуске OSD эти параметры автоматически передаются в командную строку
   процесса vitastor-osd, то есть по "статусу" они эквивалентны параметрам

docs/config/layout-cluster.en.md

@@ -33,12 +33,13 @@ Size of objects (data blocks) into which all physical and virtual drives
 in Vitastor, affects memory usage, write amplification and I/O load
 distribution effectiveness.
 
-Recommended default block size is 128 KB for SSD and 4 MB for HDD. In fact,
-it's possible to use 4 MB for SSD too - it will lower memory usage, but
+Recommended default block size is 128 KB for SSD and 1 MB for HDD. In fact,
+it's possible to use 1 MB for SSD too - it will lower memory usage, but
 may increase average WA and reduce linear performance.
 
 OSD memory usage is roughly (SIZE / BLOCK * 68 bytes) which is roughly
 544 MB per 1 TB of used disk space with the default 128 KB block size.
+With 1 MB it's 8 times lower.
 
 ## bitmap_granularity
 

docs/config/layout-cluster.ru.md

@@ -33,14 +33,14 @@ OSD) могут сосуществовать в одном кластере Vita
 настроек, влияет на потребление памяти, объём избыточной записи (write
 amplification) и эффективность распределения нагрузки по OSD.
 
-Рекомендуемые по умолчанию размеры блока - 128 килобайт для SSD и 4
-мегабайта для HDD. В принципе, для SSD можно тоже использовать 4 мегабайта,
+Рекомендуемые по умолчанию размеры блока - 128 килобайт для SSD и 1 мегабайт
+для HDD. В принципе, для SSD можно тоже использовать блок размером 1 мегабайт,
 это понизит использование памяти, но ухудшит распределение нагрузки и в
 среднем увеличит WA.
 
 Потребление памяти OSD составляет примерно (РАЗМЕР / БЛОК * 68 байт),
 т.е. примерно 544 МБ памяти на 1 ТБ занятого места на диске при
-стандартном 128 КБ блоке.
+стандартном 128 КБ блоке. При 1 МБ блоке памяти нужно в 8 раз меньше.
 
 ## bitmap_granularity
 

docs/config/layout-osd.en.md

@@ -24,6 +24,8 @@ initialization and can't be changed after it without losing data.
 - [disable_journal_fsync](#disable_journal_fsync)
 - [disable_device_lock](#disable_device_lock)
 - [disk_alignment](#disk_alignment)
+- [data_csum_type](#data_csum_type)
+- [csum_block_size](#csum_block_size)
 
 ## data_device
 
@@ -174,3 +176,43 @@ Intel Optane (probably, not tested yet).
 
 Clients don't need to be aware of disk_alignment, so it's not required to
 put a modified value into etcd key /vitastor/config/global.
+
+## data_csum_type
+
+- Type: string
+- Default: none
+
+Data checksum type to use. May be "crc32c" or "none". Set to "crc32c" to
+enable data checksums.
+
+## csum_block_size
+
+- Type: integer
+- Default: 4096
+
+Checksum calculation block size.
+
+Must be equal or a multiple of [bitmap_granularity](layout-cluster.en.md#bitmap_granularity)
+(which is usually 4 KB).
+
+Checksums increase metadata size by 4 bytes per each csum_block_size of data.
+
+Checksums are always a tradeoff:
+1. You either sacrifice +1 GB RAM per 1 TB of data
+2. Or you raise csum_block_size, for example, to 32k and sacrifice
+   50% random write iops due to checksum read-modify-write
+3. Or you turn off [inmemory_metadata](osd.en.md#inmemory_metadata) and
+   sacrifice 50% random read iops due to checksum reads
+
+All-flash clusters usually have enough RAM to use default csum_block_size,
+which uses 1 GB RAM per 1 TB of data. HDD clusters usually don't.
+
+Thus, recommended setups are:
+1. All-flash, 1 GB RAM per 1 TB data: default (csum_block_size=4k)
+2. All-flash, less RAM: csum_block_size=4k + inmemory_metadata=false
+3. Hybrid HDD+SSD: csum_block_size=4k + inmemory_metadata=false
+4. HDD-only, faster random read: csum_block_size=32k
+5. HDD-only, faster random write: csum_block_size=4k +
+   inmemory_metadata=false + cached_io_meta=true
+
+See also [cached_io_meta](osd.en.md#cached_io_meta).

docs/config/layout-osd.ru.md

@@ -25,6 +25,8 @@
 - [disable_journal_fsync](#disable_journal_fsync)
 - [disable_device_lock](#disable_device_lock)
 - [disk_alignment](#disk_alignment)
+- [data_csum_type](#data_csum_type)
+- [csum_block_size](#csum_block_size)
 
 ## data_device
 
@@ -183,3 +185,47 @@ journal_block_size и meta_block_size. Однако единственные SSD
 
 Клиентам не обязательно знать про disk_alignment, так что помещать значение
 этого параметра в etcd в /vitastor/config/global не нужно.
+
+## data_csum_type
+
+- Тип: строка
+- Значение по умолчанию: none
+
+Тип используемых OSD контрольных сумм данных. Может быть "crc32c" или "none".
+Установите в "crc32c", чтобы включить расчёт и проверку контрольных сумм данных.
+
+Следует понимать, что контрольные суммы в зависимости от размера блока их
+расчёта либо увеличивают потребление памяти, либо снижают производительность.
+Подробнее смотрите в описании параметра [csum_block_size](#csum_block_size).
+
+## csum_block_size
+
+- Тип: целое число
+- Значение по умолчанию: 4096
+
+Размер блока расчёта контрольных сумм.
+
+Должен быть равен или кратен [bitmap_granularity](layout-cluster.ru.md#bitmap_granularity)
+(который обычно равен 4 КБ).
+
+Контрольные суммы увеличивают размер метаданных на 4 байта на каждые
+csum_block_size данных.
+
+Контрольные суммы - это всегда компромисс:
+1. Вы либо жертвуете потреблением +1 ГБ памяти на 1 ТБ дискового пространства
+2. Либо вы повышаете csum_block_size до, скажем, 32k и жертвуете 50%
+   скорости случайной записи из-за цикла чтения-изменения-записи для расчёта
+   новых контрольных сумм
+3. Либо вы отключаете [inmemory_metadata](osd.ru.md#inmemory_metadata) и
+   жертвуете 50% скорости случайного чтения из-за чтения контрольных сумм
+   с диска
+
+Таким образом, рекомендуются следующие варианты настроек:
+1. All-flash, 1 ГБ памяти на 1 ТБ данных: по умолчанию (csum_block_size=4k)
+2. All-flash, меньше памяти: csum_block_size=4k + inmemory_metadata=false
+3. Гибридные HDD+SSD: csum_block_size=4k + inmemory_metadata=false
+4. Только HDD, быстрее случайное чтение: csum_block_size=32k
+5. Только HDD, быстрее случайная запись: csum_block_size=4k +
+   inmemory_metadata=false + cached_io_meta=true
+
+Смотрите также [cached_io_meta](osd.ru.md#cached_io_meta).

docs/config/osd.en.md

@@ -31,6 +31,9 @@ them, even without restarting by updating configuration in etcd.
 - [max_flusher_count](#max_flusher_count)
 - [inmemory_metadata](#inmemory_metadata)
 - [inmemory_journal](#inmemory_journal)
+- [cached_io_data](#cached_io_data)
+- [cached_io_meta](#cached_io_meta)
+- [cached_io_journal](#cached_io_journal)
 - [journal_sector_buffer_count](#journal_sector_buffer_count)
 - [journal_no_same_sector_overwrites](#journal_no_same_sector_overwrites)
 - [throttle_small_writes](#throttle_small_writes)
@@ -255,6 +258,48 @@ is typically very small because it's sufficient to have 16-32 MB journal
 for SSD OSDs. However, in theory it's possible that you'll want to turn it
 off for hybrid (HDD+SSD) OSDs with large journals on quick devices.
 
+## cached_io_data
+
+- Type: boolean
+- Default: false
+
+Read and write *data* through Linux page cache, i.e. use a file descriptor
+opened with O_SYNC, but without O_DIRECT for I/O. May improve read
+performance for hot data and slower disks - HDDs and maybe SATA SSDs.
+Not recommended for desktop SSDs without capacitors because O_SYNC flushes
+disk cache on every write.
+
+## cached_io_meta
+
+- Type: boolean
+- Default: false
+
+Read and write *metadata* through Linux page cache. May improve read
+performance only if your drives are relatively slow (HDD, SATA SSD), and
+only if checksums are enabled and [inmemory_metadata](#inmemory_metadata)
+is disabled, because in this case metadata blocks are read from disk
+on every read request to verify checksums and caching them may reduce this
+extra read load.
+
+Absolutely pointless to enable with enabled inmemory_metadata because all
+metadata is kept in memory anyway, and likely pointless without checksums,
+because in that case, metadata blocks are read from disk only during journal
+flushing.
+
+If the same device is used for data and metadata, enabling [cached_io_data](#cached_io_data)
+also enables this parameter, given that it isn't turned off explicitly.
+
+## cached_io_journal
+
+- Type: boolean
+- Default: false
+
+Read and write *journal* through Linux page cache. May improve read
+performance if [inmemory_journal](#inmemory_journal) is turned off.
+
+If the same device is used for metadata and journal, enabling [cached_io_meta](#cached_io_meta)
+also enables this parameter, given that it isn't turned off explicitly.
+
 ## journal_sector_buffer_count
 
 - Type: integer

docs/config/osd.ru.md

@@ -32,6 +32,9 @@
 - [max_flusher_count](#max_flusher_count)
 - [inmemory_metadata](#inmemory_metadata)
 - [inmemory_journal](#inmemory_journal)
+- [cached_io_data](#cached_io_data)
+- [cached_io_meta](#cached_io_meta)
+- [cached_io_journal](#cached_io_journal)
 - [journal_sector_buffer_count](#journal_sector_buffer_count)
 - [journal_no_same_sector_overwrites](#journal_no_same_sector_overwrites)
 - [throttle_small_writes](#throttle_small_writes)
@@ -263,6 +266,52 @@ Flusher - это микро-поток (корутина), которая коп
 параметра может оказаться полезным для гибридных OSD (HDD+SSD) с большими
 журналами, расположенными на быстром по сравнению с HDD устройстве.
 
+## cached_io_data
+
+- Тип: булево (да/нет)
+- Значение по умолчанию: false
+
+Читать и записывать *данные* через системный кэш Linux (page cache), то есть,
+использовать для данных файловый дескриптор, открытый без флага O_DIRECT, но
+с флагом O_SYNC. Может улучшить скорость чтения для относительно медленных
+дисков - HDD и, возможно, SATA SSD. Не рекомендуется для потребительских
+SSD без конденсаторов, так как O_SYNC сбрасывает кэш диска при каждой записи.
+
+## cached_io_meta
+
+- Тип: булево (да/нет)
+- Значение по умолчанию: false
+
+Читать и записывать *метаданные* через системный кэш Linux. Может улучшить
+скорость чтения, если у вас медленные диски, и только если контрольные суммы
+включены, а параметр [inmemory_metadata](#inmemory_metadata) отключён, так
+как в этом случае блоки метаданных читаются с диска при каждом запросе чтения
+для проверки контрольных сумм и их кэширование может снизить дополнительную
+нагрузку на диск.
+
+Абсолютно бессмысленно включать данный параметр, если параметр
+inmemory_metadata включён (по умолчанию это так), и также вероятно
+бессмысленно включать его, если не включены контрольные суммы, так как в
+этом случае блоки метаданных читаются с диска только во время сброса
+журнала.
+
+Если одно и то же устройство используется для данных и метаданных, включение
+[cached_io_data](#cached_io_data) также включает данный параметр, при
+условии, что он не отключён явным образом.
+
+## cached_io_journal
+
+- Тип: булево (да/нет)
+- Значение по умолчанию: false
+
+Читать и записывать *журнал* через системный кэш Linux. Может улучшить
+скорость чтения, если параметр [inmemory_journal](#inmemory_journal)
+отключён.
+
+Если одно и то же устройство используется для метаданных и журнала,
+включение [cached_io_meta](#cached_io_meta) также включает данный
+параметр, при условии, что он не отключён явным образом.
+
 ## journal_sector_buffer_count
 
 - Тип: целое число

docs/config/src/include.js

@@ -0,0 +1,145 @@
+#!/usr/bin/nodejs
+
+const fsp = require('fs').promises;
+
+run(process.argv).catch(console.error);
+
+async function run(argv)
+{
+    if (argv.length < 3)
+    {
+        console.log('Markdown preprocessor\nUSAGE: ./include.js file.md');
+        return;
+    }
+    const index_file = await fsp.realpath(argv[2]);
+    const re = /(\{\{[\s\S]*?\}\}|\[[^\]]+\]\([^\)]+\)|(?:^|\n)#[^\n]+)/;
+    let text = await fsp.readFile(index_file, { encoding: 'utf-8' });
+    text = text.split(re);
+    let included = {};
+    let heading = 0, heading_name = '', m;
+    for (let i = 0; i < text.length; i++)
+    {
+        if (text[i].substr(0, 2) == '{{')
+        {
+            // Inclusion
+            let incfile = text[i].substr(2, text[i].length-4);
+            let section = null;
+            let indent = heading;
+            incfile = incfile.replace(/\s*\|\s*indent\s*=\s*(-?\d+)\s*$/, (m, m1) => { indent = parseInt(m1); return ''; });
+            incfile = incfile.replace(/\s*#\s*([^#]+)$/, (m, m1) => { section = m1; return ''; });
+            let inc_heading = section;
+            incfile = rel2abs(index_file, incfile);
+            let inc = await fsp.readFile(incfile, { encoding: 'utf-8' });
+            inc = inc.trim().replace(/^[\s\S]+?\n#/, '#'); // remove until the first header
+            inc = inc.split(re);
+            const indent_str = new Array(indent+1).join('#');
+            let section_start = -1, section_end = -1;
+            for (let j = 0; j < inc.length; j++)
+            {
+                if ((m = /^(\n?)(#+\s*)([\s\S]+)$/.exec(inc[j])))
+                {
+                    if (!inc_heading)
+                    {
+                        inc_heading = m[3].trim();
+                    }
+                    if (section)
+                    {
+                        if (m[3].trim() == section)
+                            section_start = j;
+                        else if (section_start >= 0)
+                        {
+                            section_end = j;
+                            break;
+                        }
+                    }
+                    inc[j] = m[1] + indent_str + m[2] + m[3];
+                }
+                else if ((m = /^(\[[^\]]+\]\()([^\)]+)(\))$/.exec(inc[j])) && !/^https?:(\/\/)|^#/.exec(m[2]))
+                {
+                    const abs_m2 = rel2abs(incfile, m[2]);
+                    const rel_m = abs2rel(__filename, abs_m2);
+                    if (rel_m.substr(0, 9) == '../../../') // outside docs
+                        inc[j] = m[1] + 'https://git.yourcmc.ru/vitalif/vitastor/src/branch/master/'+rel2abs('docs/config/src/include.js', rel_m) + m[3];
+                    else
+                        inc[j] = m[1] + abs_m2 + m[3];
+                }
+            }
+            if (section)
+            {
+                inc = section_start >= 0 ? inc.slice(section_start, section_end < 0 ? inc.length : section_end) : [];
+            }
+            if (inc.length)
+            {
+                if (!inc_heading)
+                    inc_heading = heading_name||'';
+                included[incfile+(section ? '#'+section : '')] = '#'+inc_heading.toLowerCase().replace(/\P{L}+/ug, '-').replace(/^-|-$/g, '');
+                inc[0] = inc[0].replace(/^\s+/, '');
+                inc[inc.length-1] = inc[inc.length-1].replace(/\s+$/, '');
+            }
+            text.splice(i, 1, ...inc);
+            i = i + inc.length - 1;
+        }
+        else if ((m = /^\n?(#+)\s*([\s\S]+)$/.exec(text[i])))
+        {
+            // Heading
+            heading = m[1].length;
+            heading_name = m[2].trim();
+        }
+    }
+    for (let i = 0; i < text.length; i++)
+    {
+        if ((m = /^(\[[^\]]+\]\()([^\)]+)(\))$/.exec(text[i])) && !/^https?:(\/\/)|^#/.exec(m[2]))
+        {
+            const p = m[2].indexOf('#');
+            if (included[m[2]])
+            {
+                text[i] = m[1]+included[m[2]]+m[3];
+            }
+            else if (p >= 0 && included[m[2].substr(0, p)])
+            {
+                text[i] = m[1]+m[2].substr(p)+m[3];
+            }
+        }
+    }
+    console.log(text.join(''));
+}
+
+function rel2abs(ref, rel)
+{
+    rel = [ ...ref.replace(/^(.*)\/[^\/]+$/, '$1').split(/\/+/), ...rel.split(/\/+/) ];
+    return killdots(rel).join('/');
+}
+
+function abs2rel(ref, abs)
+{
+    ref = ref.split(/\/+/);
+    abs = abs.split(/\/+/);
+    while (ref.length > 1 && ref[0] == abs[0])
+    {
+        ref.shift();
+        abs.shift();
+    }
+    for (let i = 1; i < ref.length; i++)
+    {
+        abs.unshift('..');
+    }
+    return killdots(abs).join('/');
+}
+
+function killdots(rel)
+{
+    for (let i = 0; i < rel.length; i++)
+    {
+        if (rel[i] == '.')
+        {
+            rel.splice(i, 1);
+            i--;
+        }
+        else if (i >= 1 && rel[i] == '..' && rel[i-1] != '..')
+        {
+            rel.splice(i-1, 2);
+            i -= 2;
+        }
+    }
+    return rel;
+}

docs/config/src/included.en.md

@@ -0,0 +1,65 @@
+# Vitastor
+
+{{../../../README.md#The Idea}}
+
+{{../../../README.md#Talks and presentations}}
+
+{{../../intro/features.en.md}}
+
+{{../../intro/quickstart.en.md}}
+
+{{../../intro/architecture.en.md}}
+
+## Installation
+
+{{../../installation/packages.en.md}}
+
+{{../../installation/proxmox.en.md}}
+
+{{../../installation/openstack.en.md}}
+
+{{../../installation/kubernetes.en.md}}
+
+{{../../installation/source.en.md}}
+
+{{../../config.en.md|indent=1}}
+
+{{../../config/common.en.md|indent=2}}
+
+{{../../config/network.en.md|indent=2}}
+
+{{../../config/layout-cluster.en.md|indent=2}}
+
+{{../../config/layout-osd.en.md|indent=2}}
+
+{{../../config/osd.en.md|indent=2}}
+
+{{../../config/monitor.en.md|indent=2}}
+
+{{../../config/pool.en.md|indent=2}}
+
+{{../../config/inode.en.md|indent=2}}
+
+## Usage
+
+{{../../usage/cli.en.md}}
+
+{{../../usage/disk.en.md}}
+
+{{../../usage/fio.en.md}}
+
+{{../../usage/nbd.en.md}}
+
+{{../../usage/qemu.en.md}}
+
+{{../../usage/nfs.en.md}}
+
+## Performance
+
+{{../../performance/understanding.en.md}}
+
+{{../../performance/theoretical.en.md}}
+
+{{../../performance/comparison1.en.md}}
+
+{{../../intro/author.en.md|indent=1}}

docs/config/src/included.ru.md

@@ -0,0 +1,65 @@
+# Vitastor
+
+{{../../../README-ru.md#Идея|indent=0}}
+
+{{../../../README-ru.md#Презентации и записи докладов|indent=0}}
+
+{{../../intro/features.ru.md}}
+
+{{../../intro/quickstart.ru.md}}
+
+{{../../intro/architecture.ru.md}}
+
+## Установка
+
+{{../../installation/packages.ru.md}}
+
+{{../../installation/proxmox.ru.md}}
+
+{{../../installation/openstack.ru.md}}
+
+{{../../installation/kubernetes.ru.md}}
+
+{{../../installation/source.ru.md}}
+
+{{../../config.ru.md|indent=1}}
+
+{{../../config/common.ru.md|indent=2}}
+
+{{../../config/network.ru.md|indent=2}}
+
+{{../../config/layout-cluster.ru.md|indent=2}}
+
+{{../../config/layout-osd.ru.md|indent=2}}
+
+{{../../config/osd.ru.md|indent=2}}
+
+{{../../config/monitor.ru.md|indent=2}}
+
+{{../../config/pool.ru.md|indent=2}}
+
+{{../../config/inode.ru.md|indent=2}}
+
+## Использование
+
+{{../../usage/cli.ru.md}}
+
+{{../../usage/disk.ru.md}}
+
+{{../../usage/fio.ru.md}}
+
+{{../../usage/nbd.ru.md}}
+
+{{../../usage/qemu.ru.md}}
+
+{{../../usage/nfs.ru.md}}
+
+## Производительность
+
+{{../../performance/understanding.ru.md}}
+
+{{../../performance/theoretical.ru.md}}
+
+{{../../performance/comparison1.ru.md}}
+
+{{../../intro/author.ru.md|indent=1}}

docs/config/src/layout-cluster.yml

@@ -7,26 +7,27 @@
     in Vitastor, affects memory usage, write amplification and I/O load
     distribution effectiveness.
 
-    Recommended default block size is 128 KB for SSD and 4 MB for HDD. In fact,
-    it's possible to use 4 MB for SSD too - it will lower memory usage, but
+    Recommended default block size is 128 KB for SSD and 1 MB for HDD. In fact,
+    it's possible to use 1 MB for SSD too - it will lower memory usage, but
     may increase average WA and reduce linear performance.
 
     OSD memory usage is roughly (SIZE / BLOCK * 68 bytes) which is roughly
     544 MB per 1 TB of used disk space with the default 128 KB block size.
+    With 1 MB it's 8 times lower.
   info_ru: |
     Размер объектов (блоков данных), на которые делятся физические и виртуальные
     диски в Vitastor (в рамках каждого пула). Одна из ключевых на данный момент
     настроек, влияет на потребление памяти, объём избыточной записи (write
     amplification) и эффективность распределения нагрузки по OSD.
 
-    Рекомендуемые по умолчанию размеры блока - 128 килобайт для SSD и 4
-    мегабайта для HDD. В принципе, для SSD можно тоже использовать 4 мегабайта,
+    Рекомендуемые по умолчанию размеры блока - 128 килобайт для SSD и 1 мегабайт
+    для HDD. В принципе, для SSD можно тоже использовать блок размером 1 мегабайт,
     это понизит использование памяти, но ухудшит распределение нагрузки и в
     среднем увеличит WA.
 
     Потребление памяти OSD составляет примерно (РАЗМЕР / БЛОК * 68 байт),
     т.е. примерно 544 МБ памяти на 1 ТБ занятого места на диске при
-    стандартном 128 КБ блоке.
+    стандартном 128 КБ блоке. При 1 МБ блоке памяти нужно в 8 раз меньше.
 - name: bitmap_granularity
   type: int
   default: 4096

docs/config/src/layout-osd.yml

@@ -204,3 +204,73 @@
 
     Клиентам не обязательно знать про disk_alignment, так что помещать значение
     этого параметра в etcd в /vitastor/config/global не нужно.
+- name: data_csum_type
+  type: string
+  default: none
+  info: |
+    Data checksum type to use. May be "crc32c" or "none". Set to "crc32c" to
+    enable data checksums.
+  info_ru: |
+    Тип используемых OSD контрольных сумм данных. Может быть "crc32c" или "none".
+    Установите в "crc32c", чтобы включить расчёт и проверку контрольных сумм данных.
+
+    Следует понимать, что контрольные суммы в зависимости от размера блока их
+    расчёта либо увеличивают потребление памяти, либо снижают производительность.
+    Подробнее смотрите в описании параметра [csum_block_size](#csum_block_size).
+- name: csum_block_size
+  type: int
+  default: 4096
+  info: |
+    Checksum calculation block size.
+
+    Must be equal or a multiple of [bitmap_granularity](layout-cluster.en.md#bitmap_granularity)
+    (which is usually 4 KB).
+
+    Checksums increase metadata size by 4 bytes per each csum_block_size of data.
+
+    Checksums are always a tradeoff:
+    1. You either sacrifice +1 GB RAM per 1 TB of data
+    2. Or you raise csum_block_size, for example, to 32k and sacrifice
+       50% random write iops due to checksum read-modify-write
+    3. Or you turn off [inmemory_metadata](osd.en.md#inmemory_metadata) and
+       sacrifice 50% random read iops due to checksum reads
+
+    All-flash clusters usually have enough RAM to use default csum_block_size,
+    which uses 1 GB RAM per 1 TB of data. HDD clusters usually don't.
+
+    Thus, recommended setups are:
+    1. All-flash, 1 GB RAM per 1 TB data: default (csum_block_size=4k)
+    2. All-flash, less RAM: csum_block_size=4k + inmemory_metadata=false
+    3. Hybrid HDD+SSD: csum_block_size=4k + inmemory_metadata=false
+    4. HDD-only, faster random read: csum_block_size=32k
+    5. HDD-only, faster random write: csum_block_size=4k +
+       inmemory_metadata=false + cached_io_meta=true
+
+    See also [cached_io_meta](osd.en.md#cached_io_meta).
+  info_ru: |
+    Размер блока расчёта контрольных сумм.
+
+    Должен быть равен или кратен [bitmap_granularity](layout-cluster.ru.md#bitmap_granularity)
+    (который обычно равен 4 КБ).
+
+    Контрольные суммы увеличивают размер метаданных на 4 байта на каждые
+    csum_block_size данных.
+
+    Контрольные суммы - это всегда компромисс:
+    1. Вы либо жертвуете потреблением +1 ГБ памяти на 1 ТБ дискового пространства
+    2. Либо вы повышаете csum_block_size до, скажем, 32k и жертвуете 50%
+       скорости случайной записи из-за цикла чтения-изменения-записи для расчёта
+       новых контрольных сумм
+    3. Либо вы отключаете [inmemory_metadata](osd.ru.md#inmemory_metadata) и
+       жертвуете 50% скорости случайного чтения из-за чтения контрольных сумм
+       с диска
+
+    Таким образом, рекомендуются следующие варианты настроек:
+    1. All-flash, 1 ГБ памяти на 1 ТБ данных: по умолчанию (csum_block_size=4k)
+    2. All-flash, меньше памяти: csum_block_size=4k + inmemory_metadata=false
+    3. Гибридные HDD+SSD: csum_block_size=4k + inmemory_metadata=false
+    4. Только HDD, быстрее случайное чтение: csum_block_size=32k
+    5. Только HDD, быстрее случайная запись: csum_block_size=4k +
+       inmemory_metadata=false + cached_io_meta=true
+
+    Смотрите также [cached_io_meta](osd.ru.md#cached_io_meta).

docs/config/src/osd.yml

@@ -260,6 +260,73 @@
     достаточно 16- или 32-мегабайтного журнала. Однако в теории отключение
     параметра может оказаться полезным для гибридных OSD (HDD+SSD) с большими
     журналами, расположенными на быстром по сравнению с HDD устройстве.
+- name: cached_io_data
+  type: bool
+  default: false
+  info: |
+    Read and write *data* through Linux page cache, i.e. use a file descriptor
+    opened with O_SYNC, but without O_DIRECT for I/O. May improve read
+    performance for hot data and slower disks - HDDs and maybe SATA SSDs.
+    Not recommended for desktop SSDs without capacitors because O_SYNC flushes
+    disk cache on every write.
+  info_ru: |
+    Читать и записывать *данные* через системный кэш Linux (page cache), то есть,
+    использовать для данных файловый дескриптор, открытый без флага O_DIRECT, но
+    с флагом O_SYNC. Может улучшить скорость чтения для относительно медленных
+    дисков - HDD и, возможно, SATA SSD. Не рекомендуется для потребительских
+    SSD без конденсаторов, так как O_SYNC сбрасывает кэш диска при каждой записи.
+- name: cached_io_meta
+  type: bool
+  default: false
+  info: |
+    Read and write *metadata* through Linux page cache. May improve read
+    performance only if your drives are relatively slow (HDD, SATA SSD), and
+    only if checksums are enabled and [inmemory_metadata](#inmemory_metadata)
+    is disabled, because in this case metadata blocks are read from disk
+    on every read request to verify checksums and caching them may reduce this
+    extra read load.
+
+    Absolutely pointless to enable with enabled inmemory_metadata because all
+    metadata is kept in memory anyway, and likely pointless without checksums,
+    because in that case, metadata blocks are read from disk only during journal
+    flushing.
+
+    If the same device is used for data and metadata, enabling [cached_io_data](#cached_io_data)
+    also enables this parameter, given that it isn't turned off explicitly.
+  info_ru: |
+    Читать и записывать *метаданные* через системный кэш Linux. Может улучшить
+    скорость чтения, если у вас медленные диски, и только если контрольные суммы
+    включены, а параметр [inmemory_metadata](#inmemory_metadata) отключён, так
+    как в этом случае блоки метаданных читаются с диска при каждом запросе чтения
+    для проверки контрольных сумм и их кэширование может снизить дополнительную
+    нагрузку на диск.
+
+    Абсолютно бессмысленно включать данный параметр, если параметр
+    inmemory_metadata включён (по умолчанию это так), и также вероятно
+    бессмысленно включать его, если не включены контрольные суммы, так как в
+    этом случае блоки метаданных читаются с диска только во время сброса
+    журнала.
+
+    Если одно и то же устройство используется для данных и метаданных, включение
+    [cached_io_data](#cached_io_data) также включает данный параметр, при
+    условии, что он не отключён явным образом.
+- name: cached_io_journal
+  type: bool
+  default: false
+  info: |
+    Read and write *journal* through Linux page cache. May improve read
+    performance if [inmemory_journal](#inmemory_journal) is turned off.
+
+    If the same device is used for metadata and journal, enabling [cached_io_meta](#cached_io_meta)
+    also enables this parameter, given that it isn't turned off explicitly.
+  info_ru: |
+    Читать и записывать *журнал* через системный кэш Linux. Может улучшить
+    скорость чтения, если параметр [inmemory_journal](#inmemory_journal)
+    отключён.
+
+    Если одно и то же устройство используется для метаданных и журнала,
+    включение [cached_io_meta](#cached_io_meta) также включает данный
+    параметр, при условии, что он не отключён явным образом.
 - name: journal_sector_buffer_count
   type: int
   default: 32

docs/installation/kubernetes.ru.md

@@ -8,13 +8,13 @@
 
 У Vitastor есть CSI-плагин для Kubernetes, поддерживающий RWO, а также блочные RWX, тома.
 
-Для установки возьмите манифесты из директории [csi/deploy/](../csi/deploy/), поместите
-вашу конфигурацию подключения к Vitastor в [csi/deploy/001-csi-config-map.yaml](../csi/deploy/001-csi-config-map.yaml),
-настройте StorageClass в [csi/deploy/009-storage-class.yaml](../csi/deploy/009-storage-class.yaml)
+Для установки возьмите манифесты из директории [csi/deploy/](../../csi/deploy/), поместите
+вашу конфигурацию подключения к Vitastor в [csi/deploy/001-csi-config-map.yaml](../../csi/deploy/001-csi-config-map.yaml),
+настройте StorageClass в [csi/deploy/009-storage-class.yaml](../../csi/deploy/009-storage-class.yaml)
 и примените все `NNN-*.yaml` к вашей инсталляции Kubernetes.
 
 ```
 for i in ./???-*.yaml; do kubectl apply -f $i; done
 ```
 
-После этого вы сможете создавать PersistentVolume. Пример смотрите в файле [csi/deploy/example-pvc.yaml](../csi/deploy/example-pvc.yaml).
+После этого вы сможете создавать PersistentVolume. Пример смотрите в файле [csi/deploy/example-pvc.yaml](../../csi/deploy/example-pvc.yaml).

docs/installation/openstack.en.md

@@ -36,5 +36,5 @@ vitastor_pool_id = 1
 image_upload_use_cinder_backend = True
 ```
 
-To put Glance images in Vitastor, use [https://docs.openstack.org/cinder/pike/admin/blockstorage-volume-backed-image.html](volume-backed images),
+To put Glance images in Vitastor, use [volume-backed images](https://docs.openstack.org/cinder/pike/admin/blockstorage-volume-backed-image.html),
 although the support has not been verified yet.

docs/installation/openstack.ru.md

@@ -36,5 +36,5 @@ image_upload_use_cinder_backend = True
 ```
 
 Чтобы помещать в Vitastor Glance-образы, нужно использовать
-[https://docs.openstack.org/cinder/pike/admin/blockstorage-volume-backed-image.html](образы на основе томов Cinder),
+[образы на основе томов Cinder](https://docs.openstack.org/cinder/pike/admin/blockstorage-volume-backed-image.html),
 однако, поддержка этой функции ещё не проверялась.

docs/installation/packages.en.md

@@ -14,6 +14,8 @@
   - Debian 12 (Bookworm/Sid): `deb https://vitastor.io/debian bookworm main`
   - Debian 11 (Bullseye): `deb https://vitastor.io/debian bullseye main`
   - Debian 10 (Buster): `deb https://vitastor.io/debian buster main`
+  - Add `-oldstable` to bookworm/bullseye/buster in this line to install the last
+    stable version from 0.9.x branch instead of 1.x
 - For Debian 10 (Buster) also enable backports repository:
   `deb http://deb.debian.org/debian buster-backports main`
 - Install packages: `apt update; apt install vitastor lp-solve etcd linux-image-amd64 qemu`

docs/installation/packages.ru.md

@@ -14,6 +14,8 @@
   - Debian 12 (Bookworm/Sid): `deb https://vitastor.io/debian bookworm main`
   - Debian 11 (Bullseye): `deb https://vitastor.io/debian bullseye main`
   - Debian 10 (Buster): `deb https://vitastor.io/debian buster main`
+  - Добавьте `-oldstable` к слову bookworm/bullseye/buster в этой строке, чтобы
+    установить последнюю стабильную версию из ветки 0.9.x вместо 1.x
 - Для Debian 10 (Buster) также включите репозиторий backports:
   `deb http://deb.debian.org/debian buster-backports main`
 - Установите пакеты: `apt update; apt install vitastor lp-solve etcd linux-image-amd64 qemu`

docs/installation/proxmox.en.md

@@ -6,10 +6,10 @@
 
 # Proxmox VE
 
-To enable Vitastor support in Proxmox Virtual Environment (6.4-7.4 are supported):
+To enable Vitastor support in Proxmox Virtual Environment (6.4-8.0 are supported):
 
 - Add the corresponding Vitastor Debian repository into sources.list on Proxmox hosts:
-  buster for 6.4, bullseye for 7.4, pve7.1 for 7.1, pve7.2 for 7.2, pve7.3 for 7.3
+  bookworm for 8.0, bullseye for 7.4, pve7.3 for 7.3, pve7.2 for 7.2, pve7.1 for 7.1, buster for 6.4
 - Install vitastor-client, pve-qemu-kvm, pve-storage-vitastor (* or see note) packages from Vitastor repository
 - Define storage in `/etc/pve/storage.cfg` (see below)
 - Block network access from VMs to Vitastor network (to OSDs and etcd),
@@ -35,5 +35,5 @@ vitastor: vitastor
     vitastor_nbd 0
 ```
 
-\* Note: you can also manually copy [patches/VitastorPlugin.pm](patches/VitastorPlugin.pm) to Proxmox hosts
+\* Note: you can also manually copy [patches/VitastorPlugin.pm](../../patches/VitastorPlugin.pm) to Proxmox hosts
 as `/usr/share/perl5/PVE/Storage/Custom/VitastorPlugin.pm` instead of installing pve-storage-vitastor.

docs/installation/proxmox.ru.md

@@ -1,15 +1,15 @@
-[Документация](../../README-ru.md#документация) → Установка → Proxmox
+[Документация](../../README-ru.md#документация) → Установка → Proxmox VE
 
 -----
 
 [Read in English](proxmox.en.md)
 
-# Proxmox
+# Proxmox VE
 
-Чтобы подключить Vitastor к Proxmox Virtual Environment (поддерживаются версии 6.4-7.4):
+Чтобы подключить Vitastor к Proxmox Virtual Environment (поддерживаются версии 6.4-8.0):
 
 - Добавьте соответствующий Debian-репозиторий Vitastor в sources.list на хостах Proxmox:
-  buster для 6.4, bullseye для 7.4, pve7.1 для 7.1, pve7.2 для 7.2, pve7.3 для 7.3
+  bookworm для 8.0, bullseye для 7.4, pve7.3 для 7.3, pve7.2 для 7.2, pve7.1 для 7.1, buster для 6.4
 - Установите пакеты vitastor-client, pve-qemu-kvm, pve-storage-vitastor (* или см. сноску) из репозитория Vitastor
 - Определите тип хранилища в `/etc/pve/storage.cfg` (см. ниже)
 - Обязательно заблокируйте доступ от виртуальных машин к сети Vitastor (OSD и etcd), т.к. Vitastor (пока) не поддерживает аутентификацию
@@ -35,5 +35,5 @@ vitastor: vitastor
 ```
 
 \* Примечание: вместо установки пакета pve-storage-vitastor вы можете вручную скопировать файл
-[patches/VitastorPlugin.pm](patches/VitastorPlugin.pm) на хосты Proxmox как
+[patches/VitastorPlugin.pm](../../patches/VitastorPlugin.pm) на хосты Proxmox как
 `/usr/share/perl5/PVE/Storage/Custom/VitastorPlugin.pm`.

docs/installation/source.en.md

@@ -21,7 +21,7 @@
 
 ## Basic instructions
 
-Download source, for example using git: `git clone --recurse-submodules https://yourcmc.ru/git/vitalif/vitastor/`
+Download source, for example using git: `git clone --recurse-submodules https://git.yourcmc.ru/vitalif/vitastor/`
 
 Get `fio` source and symlink it into `<vitastor>/fio`. If you don't want to build fio engine,
 you can disable it by passing `-DWITH_FIO=no` to cmake.
@@ -41,7 +41,7 @@ It's recommended to build the QEMU driver (qemu_driver.c) in-tree, as a part of
 QEMU build process. To do that:
 - Install vitastor client library headers (from source or from vitastor-client-dev package)
 - Take a corresponding patch from `patches/qemu-*-vitastor.patch` and apply it to QEMU source
-- Copy `src/qemu_driver.c` to QEMU source directory as `block/block-vitastor.c`
+- Copy `src/qemu_driver.c` to QEMU source directory as `block/vitastor.c`
 - Build QEMU as usual
 
 But it is also possible to build it out-of-tree. To do that:

docs/installation/source.ru.md

@@ -21,7 +21,7 @@
 
 ## Базовая инструкция
 
-Скачайте исходные коды, например, из git: `git clone --recurse-submodules https://yourcmc.ru/git/vitalif/vitastor/`
+Скачайте исходные коды, например, из git: `git clone --recurse-submodules https://git.yourcmc.ru/vitalif/vitastor/`
 
 Скачайте исходные коды пакета `fio`, распакуйте их и создайте символическую ссылку на них
 в директории исходников Vitastor: `<vitastor>/fio`. Либо, если вы не хотите собирать плагин fio,
@@ -41,7 +41,7 @@ cmake .. && make -j8 install
 Драйвер QEMU (qemu_driver.c) рекомендуется собирать вместе с самим QEMU. Для этого:
 - Установите заголовки клиентской библиотеки Vitastor (из исходников или из пакета vitastor-client-dev)
 - Возьмите соответствующий патч из `patches/qemu-*-vitastor.patch` и примените его к исходникам QEMU
-- Скопируйте [src/qemu_driver.c](../../src/qemu_driver.c) в директорию исходников QEMU как `block/block-vitastor.c`
+- Скопируйте [src/qemu_driver.c](../../src/qemu_driver.c) в директорию исходников QEMU как `block/vitastor.c`
 - Соберите QEMU как обычно
 
 Однако в целях отладки драйвер также можно собирать отдельно от QEMU. Для этого:
@@ -60,7 +60,7 @@ cmake .. && make -j8 install
       * Для QEMU 2.0+: `<qemu>/qapi-types.h` &rarr; `<vitastor>/qemu/b/qemu/qapi-types.h`
    - `config-host.h` и `qapi` нужны, т.к. в них содержатся автогенерируемые заголовки
 - Сконфигурируйте cmake Vitastor с `WITH_QEMU=yes` (`cmake .. -DWITH_QEMU=yes`) и, если вы
-  используете RHEL-подобый дистрибутив, также с `QEMU_PLUGINDIR=qemu-kvm`.
+  используете RHEL-подобный дистрибутив, также с `QEMU_PLUGINDIR=qemu-kvm`.
 - После этого в процессе сборки Vitastor также будет собираться подходящий для вашей
   версии QEMU `block-vitastor.so`.
 - Таким образом можно использовать драйвер даже с немодифицированным QEMU, но в этом случае

docs/intro/architecture.en.md

@@ -44,7 +44,7 @@
   depends linearly on drive capacity and data store block size which is 128 KB by default.
   With 128 KB blocks metadata takes around 512 MB per 1 TB (which is still less than Ceph wants).
   Journal is also kept in memory by default, but in SSD-only clusters it's only 32 MB, and in SSD+HDD
-  clusters, where it's beneficial to increase it, [inmemory_journal](docs/config/osd.en.md#inmemory_journal) can be disabled.
+  clusters, where it's beneficial to increase it, [inmemory_journal](../config/osd.en.md#inmemory_journal) can be disabled.
 - Vitastor storage layer doesn't have internal copy-on-write or redirect-write. I know that maybe
   it's possible to create a good copy-on-write storage, but it's much harder and makes performance
   less deterministic, so CoW isn't used in Vitastor.

docs/intro/architecture.ru.md

@@ -156,7 +156,7 @@
   блока хранилища (block_size, по умолчанию 128 КБ). С 128 КБ блоком потребление памяти
   составляет примерно 512 МБ на 1 ТБ данных. Журналы по умолчанию тоже хранятся в памяти,
   но в SSD-кластерах нужный размер журнала составляет всего 32 МБ, а в гибридных (SSD+HDD)
-  кластерах, в которых есть смысл делать журналы больше, можно отключить [inmemory_journal](../docs/config/osd.ru.md#inmemory_journal).
+  кластерах, в которых есть смысл делать журналы больше, можно отключить [inmemory_journal](../config/osd.ru.md#inmemory_journal).
 - В Vitastor нет внутреннего copy-on-write. Я считаю, что реализация CoW-хранилища гораздо сложнее,
   поэтому сложнее добиться устойчиво хороших результатов. Возможно, в один прекрасный день
   я придумаю красивый алгоритм для CoW-хранилища, но пока нет — внутреннего CoW в Vitastor не будет.

docs/intro/features.en.md

@@ -29,13 +29,14 @@
 - Snapshots and copy-on-write image clones
 - [Write throttling to smooth random write workloads in SSD+HDD configurations](../config/osd.en.md#throttle_small_writes)
 - [RDMA/RoCEv2 support via libibverbs](../config/network.en.md#rdma_device)
-- [Scrubbing without checksums](../config/osd.en.md#auto_scrub) (verification of copies)
+- [Scrubbing](../config/osd.en.md#auto_scrub) (verification of copies)
+- [Checksums](../config/layout-osd.en.md#data_csum_type)
 
 ## Plugins and tools
 
 - [Debian and CentOS packages](../installation/packages.en.md)
 - [Image management CLI (vitastor-cli)](../usage/cli.en.md)
-- [Disk management CLI (vitastor-disk)](docs/usage/disk.en.md)
+- [Disk management CLI (vitastor-disk)](../usage/disk.en.md)
 - Generic user-space client library
 - [Native QEMU driver](../usage/qemu.en.md)
 - [Loadable fio engine for benchmarks](../usage/fio.en.md)
@@ -55,7 +56,6 @@ The following features are planned for the future:
 - iSCSI proxy
 - Multi-threaded client
 - Faster failover
-- Checksums
 - Tiered storage (SSD caching)
 - NVDIMM support
 - Compression (possibly)

docs/intro/features.ru.md

@@ -13,7 +13,7 @@
 ## Серверные функции
 
 - Базовая часть - надёжное кластерное блочное хранилище без единой точки отказа
-- [Производительность](../comparison1.ru.md) ;-D
+- [Производительность](../performance/comparison1.ru.md) ;-D
 - [Несколько схем отказоустойчивости](../config/pool.ru.md#scheme): репликация, XOR n+1 (1 диск чётности), коды коррекции ошибок
   Рида-Соломона на основе библиотек jerasure и ISA-L с любым числом дисков данных и чётности в группе
 - Конфигурация через простые человекочитаемые JSON-структуры в etcd
@@ -31,13 +31,14 @@
 - Снапшоты и copy-on-write клоны
 - [Сглаживание производительности случайной записи в SSD+HDD конфигурациях](../config/osd.ru.md#throttle_small_writes)
 - [Поддержка RDMA/RoCEv2 через libibverbs](../config/network.ru.md#rdma_device)
-- [Фоновая проверка целостности без контрольных сумм](../config/osd.ru.md#auto_scrub) (сверка копий)
+- [Фоновая проверка целостности](../config/osd.ru.md#auto_scrub) (сверка копий)
+- [Контрольные суммы](../config/layout-osd.ru.md#data_csum_type)
 
 ## Драйверы и инструменты
 
 - [Пакеты для Debian и CentOS](../installation/packages.ru.md)
 - [Консольный интерфейс управления образами (vitastor-cli)](../usage/cli.ru.md)
-- [Инструмент управления дисками (vitastor-disk)](docs/usage/disk.ru.md)
+- [Инструмент управления дисками (vitastor-disk)](../usage/disk.ru.md)
 - Общая пользовательская клиентская библиотека для работы с кластером
 - [Драйвер диска для QEMU](../usage/qemu.ru.md)
 - [Драйвер диска для утилиты тестирования производительности fio](../usage/fio.ru.md)
@@ -55,7 +56,6 @@
 - iSCSI-прокси
 - Многопоточный клиент
 - Более быстрое переключение при отказах
-- Контрольные суммы
 - Поддержка SSD-кэширования (tiered storage)
 - Поддержка NVDIMM
 - Возможно, сжатие

docs/intro/quickstart.en.md

@@ -7,6 +7,7 @@
 # Quick Start
 
 - [Preparation](#preparation)
+- [Recommended drives](#recommended-drives)
 - [Configure monitors](#configure-monitors)
 - [Configure OSDs](#configure-osds)
 - [Create a pool](#create-a-pool)
@@ -19,10 +20,20 @@
 - Get some SATA or NVMe SSDs with capacitors (server-grade drives). You can use desktop SSDs
   with lazy fsync, but prepare for inferior single-thread latency. Read more about capacitors
   [here](../config/layout-cluster.en.md#immediate_commit).
+- If you want to use HDDs, get modern HDDs with Media Cache or SSD Cache: HGST Ultrastar,
+  Toshiba MG08, Seagate EXOS or something similar. If your drives don't have such cache then
+  you also need small SSDs for journal and metadata (even 2 GB per 1 TB of HDD space is enough).
 - Get a fast network (at least 10 Gbit/s). Something like Mellanox ConnectX-4 with RoCEv2 is ideal.
 - Disable CPU powersaving: `cpupower idle-set -D 0 && cpupower frequency-set -g performance`.
 - [Install Vitastor packages](../installation/packages.en.md).
 
+## Recommended drives
+
+- SATA SSD: Micron 5100/5200/5300/5400, Samsung PM863/PM883/PM893, Intel D3-S4510/4520/4610/4620, Kingston DC500M
+- NVMe: Micron 9100/9200/9300/9400, Micron 7300/7450, Samsung PM983/PM9A3, Samsung PM1723/1735/1743,
+  Intel DC-P3700/P4500/P4600, Intel D7-P5500/P5600, Intel Optane, Kingston DC1000B/DC1500M
+- HDD: HGST Ultrastar, Toshiba MG06/MG07/MG08, Seagate EXOS
+
 ## Configure monitors
 
 On the monitor hosts:
@@ -45,9 +56,10 @@ On the monitor hosts:
   }
   ```
 - Initialize OSDs:
-  - SSD-only: `vitastor-disk prepare /dev/sdXXX [/dev/sdYYY ...]`. You can add
-    `--disable_data_fsync off` to leave disk cache enabled if you use desktop
-    SSDs without capacitors.
+  - SSD-only or HDD-only: `vitastor-disk prepare /dev/sdXXX [/dev/sdYYY ...]`.
+    Add `--disable_data_fsync off` to leave disk write cache enabled if you use
+    desktop SSDs without capacitors. Do NOT add `--disable_data_fsync off` if you
+    use HDDs or SSD+HDD.
   - Hybrid, SSD+HDD: `vitastor-disk prepare --hybrid /dev/sdXXX [/dev/sdYYY ...]`.
     Pass all your devices (HDD and SSD) to this script — it will partition disks and initialize journals on its own.
     This script skips HDDs which are already partitioned so if you want to use non-empty disks for

docs/intro/quickstart.ru.md

@@ -7,6 +7,7 @@
 # Быстрый старт
 
 - [Подготовка](#подготовка)
+- [Рекомендуемые диски](#рекомендуемые-диски)
 - [Настройте мониторы](#настройте-мониторы)
 - [Настройте OSD](#настройте-osd)
 - [Создайте пул](#создайте-пул)
@@ -19,10 +20,20 @@
 - Возьмите серверы с SSD (SATA или NVMe), желательно с конденсаторами (серверные SSD). Можно
   использовать и десктопные SSD, включив режим отложенного fsync, но производительность будет хуже.
   О конденсаторах читайте [здесь](../config/layout-cluster.ru.md#immediate_commit).
+- Если хотите использовать HDD, берите современные модели с Media или SSD кэшем - HGST Ultrastar,
+  Toshiba MG08, Seagate EXOS или что-то похожее. Если такого кэша у ваших дисков нет,
+  обязательно возьмите SSD под метаданные и журнал (маленькие, буквально 2 ГБ на 1 ТБ HDD-места).
 - Возьмите быструю сеть, минимум 10 гбит/с. Идеал - что-то вроде Mellanox ConnectX-4 с RoCEv2.
 - Для лучшей производительности отключите энергосбережение CPU: `cpupower idle-set -D 0 && cpupower frequency-set -g performance`.
 - [Установите пакеты Vitastor](../installation/packages.ru.md).
 
+## Рекомендуемые диски
+
+- SATA SSD: Micron 5100/5200/5300/5400, Samsung PM863/PM883/PM893, Intel D3-S4510/4520/4610/4620, Kingston DC500M
+- NVMe: Micron 9100/9200/9300/9400, Micron 7300/7450, Samsung PM983/PM9A3, Samsung PM1723/1735/1743,
+  Intel DC-P3700/P4500/P4600, Intel D7-P5500/P5600, Intel Optane, Kingston DC1000B/DC1500M
+- HDD: HGST Ultrastar, Toshiba MG06/MG07/MG08, Seagate EXOS
+
 ## Настройте мониторы
 
 На хостах, выделенных под мониторы:
@@ -45,9 +56,10 @@
   }
   ```
 - Инициализуйте OSD:
-  - SSD: `vitastor-disk prepare /dev/sdXXX [/dev/sdYYY ...]`. Если вы используете
-    десктопные SSD без конденсаторов, можете оставить кэш включённым, добавив
-    опцию `--disable_data_fsync off`.
+  - Только SSD или только HDD: `vitastor-disk prepare /dev/sdXXX [/dev/sdYYY ...]`.
+    Если вы используете десктопные SSD без конденсаторов, добавьте опцию `--disable_data_fsync off`,
+    чтобы оставить кэш записи диска включённым. НЕ добавляйте эту опцию, если используете
+    жёсткие диски (HDD).
   - Гибридные, SSD+HDD: `vitastor-disk prepare --hybrid /dev/sdXXX [/dev/sdYYY ...]`.
     Передайте все ваши SSD и HDD скрипту в командной строке подряд, скрипт автоматически выделит
     разделы под журналы на SSD и данные на HDD. Скрипт пропускает HDD, на которых уже есть разделы

docs/usage/disk.en.md

@@ -86,6 +86,8 @@ Options (both modes):
 --journal_size 1G/32M      Set journal size (area or partition size)
 --block_size 1M/128k       Set blockstore object size
 --bitmap_granularity 4k    Set bitmap granularity
+--data_csum_type none      Set data checksum type (crc32c or none)
+--csum_block_size 4k       Set data checksum block size
 --data_device_block 4k     Override data device block size
 --meta_device_block 4k     Override metadata device block size
 --journal_device_block 4k  Override journal device block size
@@ -100,8 +102,9 @@ checks the device cache status on start and tries to disable cache for SATA/SAS
 If it doesn't succeed it issues a warning in the system log.
 
 You can also pass other OSD options here as arguments and they'll be persisted
-to the superblock: max_write_iodepth, max_write_iodepth, min_flusher_count,
-max_flusher_count, inmemory_metadata, inmemory_journal, journal_sector_buffer_count,
+in the superblock: cached_io_data, cached_io_meta, cached_io_journal,
+inmemory_metadata, inmemory_journal, max_write_iodepth,
+min_flusher_count, max_flusher_count, journal_sector_buffer_count,
 journal_no_same_sector_overwrites, throttle_small_writes, throttle_target_iops,
 throttle_target_mbs, throttle_target_parallelism, throttle_threshold_us.
 See [Runtime OSD Parameters](../config/osd.en.md) for details.
@@ -249,7 +252,9 @@ Options (see also [Cluster-Wide Disk Layout Parameters](../config/layout-cluster
 ```
 --object_size 128k       Set blockstore block size
 --bitmap_granularity 4k  Set bitmap granularity
---journal_size 32M       Set journal size
+--journal_size 16M       Set journal size
+--data_csum_type none    Set data checksum type (crc32c or none)
+--csum_block_size 4k     Set data checksum block size
 --device_block_size 4k   Set device block size
 --journal_offset 0       Set journal offset
 --device_size 0          Set device size

docs/usage/disk.ru.md

@@ -87,6 +87,8 @@ vitastor-disk - инструмент командной строки для уп
 --journal_size 1G/32M      Задать размер журнала (области или раздела журнала)
 --block_size 1M/128k       Задать размер объекта хранилища
 --bitmap_granularity 4k    Задать гранулярность битовых карт
+--data_csum_type none      Задать тип контрольных сумм (crc32c или none)
+--csum_block_size 4k       Задать размер блока расчёта контрольных сумм
 --data_device_block 4k     Задать размер блока устройства данных
 --meta_device_block 4k     Задать размер блока метаданных
 --journal_device_block 4k  Задать размер блока журнала
@@ -101,8 +103,9 @@ vitastor-disk - инструмент командной строки для уп
 это не удаётся, в системный журнал выводится предупреждение.
 
 Вы можете передать данной команде и некоторые другие опции OSD в качестве аргументов
-и они тоже будут сохранены в суперблок: max_write_iodepth, max_write_iodepth, min_flusher_count,
-max_flusher_count, inmemory_metadata, inmemory_journal, journal_sector_buffer_count,
+и они тоже будут сохранены в суперблок: cached_io_data, cached_io_meta,
+cached_io_journal, inmemory_metadata, inmemory_journal, max_write_iodepth,
+min_flusher_count, max_flusher_count, journal_sector_buffer_count,
 journal_no_same_sector_overwrites, throttle_small_writes, throttle_target_iops,
 throttle_target_mbs, throttle_target_parallelism, throttle_threshold_us.
 Читайте об этих параметрах подробнее в разделе [Изменяемые параметры OSD](../config/osd.ru.md).
@@ -254,7 +257,9 @@ OSD отключены fsync-и.
 ```
 --object_size 128k       Размер блока хранилища
 --bitmap_granularity 4k  Гранулярность битовых карт
---journal_size 32M       Размер журнала
+--journal_size 16M       Размер журнала
+--data_csum_type none    Задать тип контрольных сумм (crc32c или none)
+--csum_block_size 4k     Задать размер блока расчёта контрольных сумм
 --device_block_size 4k   Размер блока устройства
 --journal_offset 0       Смещение журнала
 --device_size 0          Размер устройства

docs/usage/nbd.en.md

@@ -13,6 +13,8 @@ remains decent (see an example [here](../performance/comparison1.en.md#vitastor-
 
 Vitastor Kubernetes CSI driver is based on NBD.
 
+See also [VDUSE](qemu.en.md#vduse).
+
 ## Map image
 
 To create a local block device for a Vitastor image run:

docs/usage/nbd.ru.md

@@ -16,6 +16,8 @@ NBD немного снижает производительность из-за
 
 CSI-драйвер Kubernetes Vitastor основан на NBD.
 
+Смотрите также [VDUSE](qemu.ru.md#vduse).
+
 ## Подключить устройство
 
 Чтобы создать локальное блочное устройство для образа, выполните команду:

docs/usage/nfs.ru.md

@@ -29,7 +29,7 @@ vitastor-nfs [--etcd_address ADDR] [ДРУГИЕ ОПЦИИ]
 --bind <IP>       принимать соединения по адресу <IP> (по умолчанию 0.0.0.0 - на всех)
 --nfspath <PATH>  установить путь NFS-экспорта в <PATH> (по умолчанию /)
 --port <PORT>     использовать порт <PORT> для NFS-сервисов (по умолчанию 2049)
---pool <POOL>     исползовать пул <POOL> для новых образов (обязательно, если пул в кластере не один)
+--pool <POOL>     использовать пул <POOL> для новых образов (обязательно, если пул в кластере не один)
 --foreground 1    не уходить в фон после запуска
 ```
 

docs/usage/qemu.en.md

@@ -83,3 +83,44 @@ qemu-img rebase -u -b '' testimg.qcow2
 This can be used for backups. Just note that exporting an image that is currently being written to
 is of course unsafe and doesn't produce a consistent result, so only export snapshots if you do this
 on a live VM.
+
+## VDUSE
+
+Linux kernel, starting with version 5.15, supports a new interface for attaching virtual disks
+to the host - VDUSE (vDPA Device in Userspace). QEMU, starting with 7.2, has support for
+exporting QEMU block devices over this protocol using qemu-storage-daemon.
+
+VDUSE has the same problem as other FUSE-like interfaces in Linux: if a userspace process hangs,
+for example, if it loses connectivity with Vitastor cluster - active processes doing I/O may
+hang in the D state (uninterruptible sleep) and you won't be able to kill them even with kill -9.
+In this case reboot will be the only way to remove VDUSE devices from system.
+
+On the other hand, VDUSE is faster than [NBD](nbd.en.md), so you may prefer to use it if
+performance is important for you. Approximate performance numbers:
+direct fio benchmark - 115000 iops, NBD - 60000 iops, VDUSE - 90000 iops.
+
+To try VDUSE you need at least Linux 5.15, built with VDUSE support
+(CONFIG_VIRTIO_VDPA=m and CONFIG_VDPA_USER=m). Debian Linux kernels have these options
+disabled by now, so if you want to try it on Debian, use a kernel from Ubuntu
+[kernel-ppa/mainline](https://kernel.ubuntu.com/~kernel-ppa/mainline/) or Proxmox.
+
+Commands to attach Vitastor image as a VDUSE device:
+
+```
+modprobe vduse
+modprobe virtio-vdpa
+qemu-storage-daemon --daemonize --blockdev '{"node-name":"test1","driver":"vitastor",\
+  "etcd-host":"192.168.7.2:2379/v3","image":"testosd1","cache":{"direct":true,"no-flush":false},"discard":"unmap"}' \
+  --export vduse-blk,id=test1,node-name=test1,name=test1,num-queues=16,queue-size=128,writable=true
+vdpa dev add name test1 mgmtdev vduse
+```
+
+After running these commands /dev/vda device will appear in the system and you'll be able to
+use it as a normal disk.
+
+To remove the device:
+
+```
+vdpa dev del test1
+kill <qemu-storage-daemon_process_PID>
+```

docs/usage/qemu.ru.md

@@ -87,3 +87,44 @@ qemu-img rebase -u -b '' testimg.qcow2
 Это можно использовать для резервного копирования. Только помните, что экспортировать образ, в который
 в то же время идёт запись, небезопасно - результат чтения не будет целостным. Так что если вы работаете
 с активными виртуальными машинами, экспортируйте только их снимки, но не сам образ.
+
+## VDUSE
+
+В Linux, начиная с версии ядра 5.15, доступен новый интерфейс для подключения виртуальных дисков
+к системе - VDUSE (vDPA Device in Userspace), а в QEMU, начиная с версии 7.2, есть поддержка
+экспорта блочных устройств QEMU по этому протоколу через qemu-storage-daemon.
+
+VDUSE страдает общей проблемой FUSE-подобных интерфейсов в Linux: если пользовательский процесс
+подвиснет, например, если будет потеряна связь с кластером Vitastor - читающие/пишущие в кластер
+процессы могут "залипнуть" в состоянии D (непрерываемый сон) и их будет невозможно убить даже
+через kill -9. В этом случае удалить из системы устройство можно только перезагрузившись.
+
+С другой стороны, VDUSE быстрее по сравнению с [NBD](nbd.ru.md), поэтому его может
+быть предпочтительно использовать там, где производительность важнее. Порядок показателей:
+прямое тестирование через fio - 115000 iops, NBD - 60000 iops, VDUSE - 90000 iops.
+
+Чтобы использовать VDUSE, вам нужно ядро Linux версии хотя бы 5.15, собранное с поддержкой
+VDUSE (CONFIG_VIRTIO_VDPA=m и CONFIG_VDPA_USER=m). В ядрах в Debian Linux поддержка пока
+отключена - если хотите попробовать эту функцию на Debian, поставьте ядро из Ubuntu
+[kernel-ppa/mainline](https://kernel.ubuntu.com/~kernel-ppa/mainline/) или из Proxmox.
+
+Команды для подключения виртуального диска через VDUSE:
+
+```
+modprobe vduse
+modprobe virtio-vdpa
+qemu-storage-daemon --daemonize --blockdev '{"node-name":"test1","driver":"vitastor",\
+  "etcd-host":"192.168.7.2:2379/v3","image":"testosd1","cache":{"direct":true,"no-flush":false},"discard":"unmap"}' \
+  --export vduse-blk,id=test1,node-name=test1,name=test1,num-queues=16,queue-size=128,writable=true
+vdpa dev add name test1 mgmtdev vduse
+```
+
+После этого в системе появится устройство /dev/vda, которое можно будет использовать как
+обычный диск.
+
+Для удаления устройства из системы:
+
+```
+vdpa dev del test1
+kill <PID_процесса_qemu-storage-daemon>
+```

mon/make-etcd

@@ -63,8 +63,9 @@ Wants=network-online.target local-fs.target time-sync.target
 
 [Service]
 Restart=always
-ExecStart=/usr/local/bin/etcd -name etcd${num} --data-dir /var/lib/etcd${num}.etcd \\
-    --advertise-client-urls http://${etcds[num]}:2379 --listen-client-urls http://${etcds[num]}:2379 \\
+Environment=GOGC=50
+ExecStart=etcd -name etcd${num} --data-dir /var/lib/etcd${num}.etcd \\
+    --snapshot-count 10000 --advertise-client-urls http://${etcds[num]}:2379 --listen-client-urls http://${etcds[num]}:2379 \\
     --initial-advertise-peer-urls http://${etcds[num]}:2380 --listen-peer-urls http://${etcds[num]}:2380 \\
     --initial-cluster-token vitastor-etcd-1 --initial-cluster ${etcd_cluster} \\
     --initial-cluster-state new --max-txn-ops=100000 --max-request-bytes=104857600 \\

mon/mon.js

@@ -539,10 +539,18 @@ class Mon
         {
             retries = 1;
         }
+        const tried = {};
         while (retries < 0 || retry < retries)
         {
             const cur_addr = this.pick_next_etcd();
             const base = 'ws'+cur_addr.substr(4);
+            let now = Date.now();
+            if (tried[base] && now-tried[base] < timeout)
+            {
+                await new Promise(ok => setTimeout(ok, timeout-(now-tried[base])));
+                now = Date.now();
+            }
+            tried[base] = now;
             const ok = await new Promise((ok, no) =>
             {
                 const timer_id = setTimeout(() =>
@@ -1497,10 +1505,14 @@ class Mon
                     break;
                 }
             }
+            const pool_cfg = (this.state.config.pools[pool_id]||{});
             if (!object_size)
             {
-                object_size = (this.state.config.pools[pool_id]||{}).block_size ||
-                    this.config.block_size || 131072;
+                object_size = pool_cfg.block_size || this.config.block_size || 131072;
+            }
+            if (pool_cfg.scheme !== 'replicated')
+            {
+                object_size *= ((pool_cfg.pg_size||0) - (pool_cfg.parity_chunks||0));
             }
             object_size = BigInt(object_size);
             for (const pg_num in this.state.pg.stats[pool_id])
@@ -1608,7 +1620,7 @@ class Mon
                 }
             }
         }
-        return inode_stats;
+        return { inode_stats, seen_pools };
     }
 
     serialize_bigints(obj)
@@ -1634,7 +1646,7 @@ class Mon
         const timestamp = Date.now();
         const { object_counts, object_bytes } = this.sum_object_counts();
         let stats = this.sum_op_stats(timestamp, this.prev_stats);
-        let inode_stats = this.sum_inode_stats(
+        let { inode_stats, seen_pools } = this.sum_inode_stats(
             this.prev_stats ? this.prev_stats.inode_stats : null,
             timestamp, this.prev_stats ? this.prev_stats.timestamp : null
         );
@@ -1669,12 +1681,22 @@ class Mon
         }
         for (const pool_id in this.state.pool.stats)
         {
-            const pool_stats = { ...this.state.pool.stats[pool_id] };
-            this.serialize_bigints(pool_stats);
-            txn.push({ requestPut: {
-                key: b64(this.etcd_prefix+'/pool/stats/'+pool_id),
-                value: b64(JSON.stringify(pool_stats)),
-            } });
+            if (!seen_pools[pool_id])
+            {
+                txn.push({ requestDeleteRange: {
+                    key: b64(this.etcd_prefix+'/pool/stats/'+pool_id),
+                } });
+                delete this.state.pool.stats[pool_id];
+            }
+            else
+            {
+                const pool_stats = { ...this.state.pool.stats[pool_id] };
+                this.serialize_bigints(pool_stats);
+                txn.push({ requestPut: {
+                    key: b64(this.etcd_prefix+'/pool/stats/'+pool_id),
+                    value: b64(JSON.stringify(pool_stats)),
+                } });
+            }
         }
         if (txn.length)
         {
@@ -1774,10 +1796,18 @@ class Mon
         {
             retries = 1;
         }
+        const tried = {};
         while (retries < 0 || retry < retries)
         {
             retry++;
             const base = this.pick_next_etcd();
+            let now = Date.now();
+            if (tried[base] && now-tried[base] < timeout)
+            {
+                await new Promise(ok => setTimeout(ok, timeout-(now-tried[base])));
+                now = Date.now();
+            }
+            tried[base] = now;
             const res = await POST(base+path, body, timeout);
             if (res.error)
             {

patches/cinder-vitastor.py

@@ -50,7 +50,7 @@ from cinder.volume import configuration
 from cinder.volume import driver
 from cinder.volume import volume_utils
 
-VERSION = '0.9.2'
+VERSION = '1.0.0'
 
 LOG = logging.getLogger(__name__)
 

patches/pve-qemu-8.0-vitastor.patch

@@ -0,0 +1,190 @@
+diff --git a/block/meson.build b/block/meson.build
+index 382bec0e7d..af6207dbce 100644
+--- a/block/meson.build
++++ b/block/meson.build
+@@ -114,6 +114,7 @@ foreach m : [
+   [libnfs, 'nfs', files('nfs.c')],
+   [libssh, 'ssh', files('ssh.c')],
+   [rbd, 'rbd', files('rbd.c')],
++  [vitastor, 'vitastor', files('vitastor.c')],
+ ]
+   if m[0].found()
+     module_ss = ss.source_set()
+diff --git a/meson.build b/meson.build
+index c44d05a13f..ebedb42843 100644
+--- a/meson.build
++++ b/meson.build
+@@ -1028,6 +1028,26 @@ if not get_option('rbd').auto() or have_block
+   endif
+ endif
+ 
++vitastor = not_found
++if not get_option('vitastor').auto() or have_block
++  libvitastor_client = cc.find_library('vitastor_client', has_headers: ['vitastor_c.h'],
++    required: get_option('vitastor'), kwargs: static_kwargs)
++  if libvitastor_client.found()
++    if cc.links('''
++      #include <vitastor_c.h>
++      int main(void) {
++        vitastor_c_create_qemu(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
++        return 0;
++      }''', dependencies: libvitastor_client)
++      vitastor = declare_dependency(dependencies: libvitastor_client)
++    elif get_option('vitastor').enabled()
++      error('could not link libvitastor_client')
++    else
++      warning('could not link libvitastor_client, disabling')
++    endif
++  endif
++endif
++
+ glusterfs = not_found
+ glusterfs_ftruncate_has_stat = false
+ glusterfs_iocb_has_stat = false
+@@ -1882,6 +1902,7 @@ endif
+ config_host_data.set('CONFIG_OPENGL', opengl.found())
+ config_host_data.set('CONFIG_PROFILER', get_option('profiler'))
+ config_host_data.set('CONFIG_RBD', rbd.found())
++config_host_data.set('CONFIG_VITASTOR', vitastor.found())
+ config_host_data.set('CONFIG_RDMA', rdma.found())
+ config_host_data.set('CONFIG_SDL', sdl.found())
+ config_host_data.set('CONFIG_SDL_IMAGE', sdl_image.found())
+@@ -4020,6 +4041,7 @@ if spice_protocol.found()
+   summary_info += {'  spice server support': spice}
+ endif
+ summary_info += {'rbd support':       rbd}
++summary_info += {'vitastor support':  vitastor}
+ summary_info += {'smartcard support': cacard}
+ summary_info += {'U2F support':       u2f}
+ summary_info += {'libusb':            libusb}
+diff --git a/meson_options.txt b/meson_options.txt
+index fc9447d267..c4ac55c283 100644
+--- a/meson_options.txt
++++ b/meson_options.txt
+@@ -173,6 +173,8 @@ option('lzo', type : 'feature', value : 'auto',
+        description: 'lzo compression support')
+ option('rbd', type : 'feature', value : 'auto',
+        description: 'Ceph block device driver')
++option('vitastor', type : 'feature', value : 'auto',
++       description: 'Vitastor block device driver')
+ option('opengl', type : 'feature', value : 'auto',
+        description: 'OpenGL support')
+ option('rdma', type : 'feature', value : 'auto',
+diff --git a/qapi/block-core.json b/qapi/block-core.json
+index c05ad0c07e..f5eb701604 100644
+--- a/qapi/block-core.json
++++ b/qapi/block-core.json
+@@ -3308,7 +3308,7 @@
+             'raw', 'rbd',
+             { 'name': 'replication', 'if': 'CONFIG_REPLICATION' },
+             'pbs',
+-            'ssh', 'throttle', 'vdi', 'vhdx',
++            'ssh', 'throttle', 'vdi', 'vhdx', 'vitastor',
+             { 'name': 'virtio-blk-vfio-pci', 'if': 'CONFIG_BLKIO' },
+             { 'name': 'virtio-blk-vhost-user', 'if': 'CONFIG_BLKIO' },
+             { 'name': 'virtio-blk-vhost-vdpa', 'if': 'CONFIG_BLKIO' },
+@@ -4338,6 +4338,28 @@
+             '*key-secret': 'str',
+             '*server': ['InetSocketAddressBase'] } }
+ 
++##
++# @BlockdevOptionsVitastor:
++#
++# Driver specific block device options for vitastor
++#
++# @image:       Image name
++# @inode:       Inode number
++# @pool:        Pool ID
++# @size:        Desired image size in bytes
++# @config-path: Path to Vitastor configuration
++# @etcd-host:   etcd connection address(es)
++# @etcd-prefix: etcd key/value prefix
++##
++{ 'struct': 'BlockdevOptionsVitastor',
++  'data': { '*inode': 'uint64',
++            '*pool': 'uint64',
++            '*size': 'uint64',
++            '*image': 'str',
++            '*config-path': 'str',
++            '*etcd-host': 'str',
++            '*etcd-prefix': 'str' } }
++
+ ##
+ # @ReplicationMode:
+ #
+@@ -4787,6 +4809,7 @@
+       'throttle':   'BlockdevOptionsThrottle',
+       'vdi':        'BlockdevOptionsGenericFormat',
+       'vhdx':       'BlockdevOptionsGenericFormat',
++      'vitastor':   'BlockdevOptionsVitastor',
+       'virtio-blk-vfio-pci':
+                     { 'type': 'BlockdevOptionsVirtioBlkVfioPci',
+                       'if': 'CONFIG_BLKIO' },
+@@ -5187,6 +5210,17 @@
+             '*cluster-size' :   'size',
+             '*encrypt' :        'RbdEncryptionCreateOptions' } }
+ 
++##
++# @BlockdevCreateOptionsVitastor:
++#
++# Driver specific image creation options for Vitastor.
++#
++# @size: Size of the virtual disk in bytes
++##
++{ 'struct': 'BlockdevCreateOptionsVitastor',
++  'data': { 'location':         'BlockdevOptionsVitastor',
++            'size':             'size' } }
++
+ ##
+ # @BlockdevVmdkSubformat:
+ #
+@@ -5385,6 +5419,7 @@
+       'ssh':            'BlockdevCreateOptionsSsh',
+       'vdi':            'BlockdevCreateOptionsVdi',
+       'vhdx':           'BlockdevCreateOptionsVhdx',
++      'vitastor':       'BlockdevCreateOptionsVitastor',
+       'vmdk':           'BlockdevCreateOptionsVmdk',
+       'vpc':            'BlockdevCreateOptionsVpc'
+   } }
+diff --git a/scripts/ci/org.centos/stream/8/x86_64/configure b/scripts/ci/org.centos/stream/8/x86_64/configure
+index 6e8983f39c..1b0b9fcf3e 100755
+--- a/scripts/ci/org.centos/stream/8/x86_64/configure
++++ b/scripts/ci/org.centos/stream/8/x86_64/configure
+@@ -32,7 +32,7 @@
+ --with-git=meson \
+ --with-git-submodules=update \
+ --target-list="x86_64-softmmu" \
+---block-drv-rw-whitelist="qcow2,raw,file,host_device,nbd,iscsi,rbd,blkdebug,luks,null-co,nvme,copy-on-read,throttle,gluster" \
++--block-drv-rw-whitelist="qcow2,raw,file,host_device,nbd,iscsi,rbd,vitastor,blkdebug,luks,null-co,nvme,copy-on-read,throttle,gluster" \
+ --audio-drv-list="" \
+ --block-drv-ro-whitelist="vmdk,vhdx,vpc,https,ssh" \
+ --with-coroutine=ucontext \
+@@ -179,6 +179,7 @@
+ --enable-opengl \
+ --enable-pie \
+ --enable-rbd \
++--enable-vitastor \
+ --enable-rdma \
+ --enable-seccomp \
+ --enable-snappy \
+diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
+index 009fab1515..95914e6ebc 100644
+--- a/scripts/meson-buildoptions.sh
++++ b/scripts/meson-buildoptions.sh
+@@ -144,6 +144,7 @@ meson_options_help() {
+   printf "%s\n" '  qed             qed image format support'
+   printf "%s\n" '  qga-vss         build QGA VSS support (broken with MinGW)'
+   printf "%s\n" '  rbd             Ceph block device driver'
++  printf "%s\n" '  vitastor        Vitastor block device driver'
+   printf "%s\n" '  rdma            Enable RDMA-based migration'
+   printf "%s\n" '  replication     replication support'
+   printf "%s\n" '  sdl             SDL user interface'
+@@ -392,6 +393,8 @@ _meson_option_parse() {
+     --disable-qom-cast-debug) printf "%s" -Dqom_cast_debug=false ;;
+     --enable-rbd) printf "%s" -Drbd=enabled ;;
+     --disable-rbd) printf "%s" -Drbd=disabled ;;
++    --enable-vitastor) printf "%s" -Dvitastor=enabled ;;
++    --disable-vitastor) printf "%s" -Dvitastor=disabled ;;
+     --enable-rdma) printf "%s" -Drdma=enabled ;;
+     --disable-rdma) printf "%s" -Drdma=disabled ;;
+     --enable-replication) printf "%s" -Dreplication=enabled ;;

patches/qemu-2.12-vitastor.patch

@@ -0,0 +1,176 @@
+diff --git a/block/Makefile.objs b/block/Makefile.objs
+index d644bac60a..e404236291 100644
+--- a/block/Makefile.objs
++++ b/block/Makefile.objs
+@@ -19,6 +19,7 @@ block-obj-$(if $(CONFIG_LIBISCSI),y,n) += iscsi-opts.o
+ block-obj-$(CONFIG_LIBNFS) += nfs.o
+ block-obj-$(CONFIG_CURL) += curl.o
+ block-obj-$(CONFIG_RBD) += rbd.o
++block-obj-$(CONFIG_VITASTOR) += vitastor.o
+ block-obj-$(CONFIG_GLUSTERFS) += gluster.o
+ block-obj-$(CONFIG_VXHS) += vxhs.o
+ block-obj-$(CONFIG_LIBSSH2) += ssh.o
+@@ -39,6 +40,8 @@ curl.o-cflags      := $(CURL_CFLAGS)
+ curl.o-libs        := $(CURL_LIBS)
+ rbd.o-cflags       := $(RBD_CFLAGS)
+ rbd.o-libs         := $(RBD_LIBS)
++vitastor.o-cflags  := $(VITASTOR_CFLAGS)
++vitastor.o-libs    := $(VITASTOR_LIBS)
+ gluster.o-cflags   := $(GLUSTERFS_CFLAGS)
+ gluster.o-libs     := $(GLUSTERFS_LIBS)
+ vxhs.o-libs        := $(VXHS_LIBS)
+diff --git a/configure b/configure
+index 0a19b033bc..58b7fbf24c 100755
+--- a/configure
++++ b/configure
+@@ -398,6 +398,7 @@ trace_backends="log"
+ trace_file="trace"
+ spice=""
+ rbd=""
++vitastor=""
+ smartcard=""
+ libusb=""
+ usb_redir=""
+@@ -1213,6 +1214,10 @@ for opt do
+   ;;
+   --enable-rbd) rbd="yes"
+   ;;
++  --disable-vitastor) vitastor="no"
++  ;;
++  --enable-vitastor) vitastor="yes"
++  ;;
+   --disable-xfsctl) xfs="no"
+   ;;
+   --enable-xfsctl) xfs="yes"
+@@ -1601,6 +1606,7 @@ disabled with --disable-FEATURE, default is enabled if available:
+   vhost-crypto    vhost-crypto acceleration support
+   spice           spice
+   rbd             rados block device (rbd)
++  vitastor        vitastor block device
+   libiscsi        iscsi support
+   libnfs          nfs support
+   smartcard       smartcard support (libcacard)
+@@ -3594,6 +3600,27 @@ EOF
+   fi
+ fi
+ 
++##########################################
++# vitastor probe
++if test "$vitastor" != "no" ; then
++  cat > $TMPC <<EOF
++#include <vitastor_c.h>
++int main(void) {
++  vitastor_c_create_qemu(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
++  return 0;
++}
++EOF
++  vitastor_libs="-lvitastor_client"
++  if compile_prog "" "$vitastor_libs" ; then
++    vitastor=yes
++  else
++    if test "$vitastor" = "yes" ; then
++      feature_not_found "vitastor block device" "Install vitastor-client-dev"
++    fi
++    vitastor=no
++  fi
++fi
++
+ ##########################################
+ # libssh2 probe
+ min_libssh2_version=1.2.8
+@@ -5837,6 +5864,7 @@ echo "Trace output file $trace_file-<pid>"
+ fi
+ echo "spice support     $spice $(echo_version $spice $spice_protocol_version/$spice_server_version)"
+ echo "rbd support       $rbd"
++echo "vitastor support  $vitastor"
+ echo "xfsctl support    $xfs"
+ echo "smartcard support $smartcard"
+ echo "libusb            $libusb"
+@@ -6416,6 +6444,11 @@ if test "$rbd" = "yes" ; then
+   echo "RBD_CFLAGS=$rbd_cflags" >> $config_host_mak
+   echo "RBD_LIBS=$rbd_libs" >> $config_host_mak
+ fi
++if test "$vitastor" = "yes" ; then
++  echo "CONFIG_VITASTOR=m" >> $config_host_mak
++  echo "VITASTOR_CFLAGS=$vitastor_cflags" >> $config_host_mak
++  echo "VITASTOR_LIBS=$vitastor_libs" >> $config_host_mak
++fi
+ 
+ echo "CONFIG_COROUTINE_BACKEND=$coroutine" >> $config_host_mak
+ if test "$coroutine_pool" = "yes" ; then
+diff --git a/qapi/block-core.json b/qapi/block-core.json
+index c50517bff3..c780bb2c1c 100644
+--- a/qapi/block-core.json
++++ b/qapi/block-core.json
+@@ -2514,7 +2514,7 @@
+             'dmg', 'file', 'ftp', 'ftps', 'gluster', 'host_cdrom',
+             'host_device', 'http', 'https', 'iscsi', 'luks', 'nbd', 'nfs',
+             'null-aio', 'null-co', 'nvme', 'parallels', 'qcow', 'qcow2', 'qed',
+-            'quorum', 'raw', 'rbd', 'replication', 'sheepdog', 'ssh',
++            'quorum', 'raw', 'rbd', 'vitastor', 'replication', 'sheepdog', 'ssh',
+             'throttle', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat', 'vxhs' ] }
+ 
+ ##
+@@ -3217,6 +3217,28 @@
+             '*snap-id': 'uint32',
+             '*tag': 'str' } }
+ 
++##
++# @BlockdevOptionsVitastor:
++#
++# Driver specific block device options for vitastor
++#
++# @image:       Image name
++# @inode:       Inode number
++# @pool:        Pool ID
++# @size:        Desired image size in bytes
++# @config-path: Path to Vitastor configuration
++# @etcd-host:   etcd connection address(es)
++# @etcd-prefix: etcd key/value prefix
++##
++{ 'struct': 'BlockdevOptionsVitastor',
++  'data': { '*inode': 'uint64',
++            '*pool': 'uint64',
++            '*size': 'uint64',
++            '*image': 'str',
++            '*config-path': 'str',
++            '*etcd-host': 'str',
++            '*etcd-prefix': 'str' } }
++
+ ##
+ # @ReplicationMode:
+ #
+@@ -3547,6 +3569,7 @@
+       'rbd':        'BlockdevOptionsRbd',
+       'replication':'BlockdevOptionsReplication',
+       'sheepdog':   'BlockdevOptionsSheepdog',
++      'vitastor':   'BlockdevOptionsVitastor',
+       'ssh':        'BlockdevOptionsSsh',
+       'throttle':   'BlockdevOptionsThrottle',
+       'vdi':        'BlockdevOptionsGenericFormat',
+@@ -3991,6 +4014,17 @@
+             '*subformat':           'BlockdevVhdxSubformat',
+             '*block-state-zero':    'bool' } }
+ 
++##
++# @BlockdevCreateOptionsVitastor:
++#
++# Driver specific image creation options for Vitastor.
++#
++# @size: Size of the virtual disk in bytes
++##
++{ 'struct': 'BlockdevCreateOptionsVitastor',
++  'data': { 'location':         'BlockdevOptionsVitastor',
++            'size':             'size' } }
++
+ ##
+ # @BlockdevVpcSubformat:
+ #
+@@ -4074,6 +4108,7 @@
+       'rbd':            'BlockdevCreateOptionsRbd',
+       'replication':    'BlockdevCreateNotSupported',
+       'sheepdog':       'BlockdevCreateOptionsSheepdog',
++      'vitastor':       'BlockdevCreateOptionsVitastor',
+       'ssh':            'BlockdevCreateOptionsSsh',
+       'throttle':       'BlockdevCreateNotSupported',
+       'vdi':            'BlockdevCreateOptionsVdi',

patches/qemu-5.2-vitastor.patch

@@ -0,0 +1,181 @@
+Index: qemu-5.2+dfsg/qapi/block-core.json
+===================================================================
+--- qemu-5.2+dfsg.orig/qapi/block-core.json
++++ qemu-5.2+dfsg/qapi/block-core.json
+@@ -2831,7 +2831,7 @@
+             'luks', 'nbd', 'nfs', 'null-aio', 'null-co', 'nvme', 'parallels',
+             'qcow', 'qcow2', 'qed', 'quorum', 'raw', 'rbd',
+             { 'name': 'replication', 'if': 'defined(CONFIG_REPLICATION)' },
+-            'sheepdog',
++            'sheepdog', 'vitastor',
+             'ssh', 'throttle', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat' ] }
+ 
+ ##
+@@ -3668,6 +3668,28 @@
+             '*tag': 'str' } }
+ 
+ ##
++# @BlockdevOptionsVitastor:
++#
++# Driver specific block device options for vitastor
++#
++# @image:       Image name
++# @inode:       Inode number
++# @pool:        Pool ID
++# @size:        Desired image size in bytes
++# @config-path: Path to Vitastor configuration
++# @etcd-host:   etcd connection address(es)
++# @etcd-prefix: etcd key/value prefix
++##
++{ 'struct': 'BlockdevOptionsVitastor',
++  'data': { '*inode': 'uint64',
++            '*pool': 'uint64',
++            '*size': 'uint64',
++            '*image': 'str',
++            '*config-path': 'str',
++            '*etcd-host': 'str',
++            '*etcd-prefix': 'str' } }
++
++##
+ # @ReplicationMode:
+ #
+ # An enumeration of replication modes.
+@@ -4015,6 +4037,7 @@
+       'replication': { 'type': 'BlockdevOptionsReplication',
+                        'if': 'defined(CONFIG_REPLICATION)' },
+       'sheepdog':   'BlockdevOptionsSheepdog',
++      'vitastor':   'BlockdevOptionsVitastor',
+       'ssh':        'BlockdevOptionsSsh',
+       'throttle':   'BlockdevOptionsThrottle',
+       'vdi':        'BlockdevOptionsGenericFormat',
+@@ -4404,6 +4427,17 @@
+             '*cluster-size' :   'size' } }
+ 
+ ##
++# @BlockdevCreateOptionsVitastor:
++#
++# Driver specific image creation options for Vitastor.
++#
++# @size: Size of the virtual disk in bytes
++##
++{ 'struct': 'BlockdevCreateOptionsVitastor',
++  'data': { 'location':         'BlockdevOptionsVitastor',
++            'size':             'size' } }
++
++##
+ # @BlockdevVmdkSubformat:
+ #
+ # Subformat options for VMDK images
+@@ -4665,6 +4699,7 @@
+       'qed':            'BlockdevCreateOptionsQed',
+       'rbd':            'BlockdevCreateOptionsRbd',
+       'sheepdog':       'BlockdevCreateOptionsSheepdog',
++      'vitastor':       'BlockdevCreateOptionsVitastor',
+       'ssh':            'BlockdevCreateOptionsSsh',
+       'vdi':            'BlockdevCreateOptionsVdi',
+       'vhdx':           'BlockdevCreateOptionsVhdx',
+Index: qemu-5.2+dfsg/block/meson.build
+===================================================================
+--- qemu-5.2+dfsg.orig/block/meson.build
++++ qemu-5.2+dfsg/block/meson.build
+@@ -76,6 +76,7 @@ foreach m : [
+   ['CONFIG_LIBNFS', 'nfs', libnfs, 'nfs.c'],
+   ['CONFIG_LIBSSH', 'ssh', libssh, 'ssh.c'],
+   ['CONFIG_RBD', 'rbd', rbd, 'rbd.c'],
++  ['CONFIG_VITASTOR', 'vitastor', vitastor, 'vitastor.c'],
+ ]
+   if config_host.has_key(m[0])
+     if enable_modules
+Index: qemu-5.2+dfsg/configure
+===================================================================
+--- qemu-5.2+dfsg.orig/configure
++++ qemu-5.2+dfsg/configure
+@@ -372,6 +372,7 @@ trace_backends="log"
+ trace_file="trace"
+ spice=""
+ rbd=""
++vitastor=""
+ smartcard=""
+ u2f="auto"
+ libusb=""
+@@ -1263,6 +1264,10 @@ for opt do
+   ;;
+   --enable-rbd) rbd="yes"
+   ;;
++  --disable-vitastor) vitastor="no"
++  ;;
++  --enable-vitastor) vitastor="yes"
++  ;;
+   --disable-xfsctl) xfs="no"
+   ;;
+   --enable-xfsctl) xfs="yes"
+@@ -1827,6 +1832,7 @@ disabled with --disable-FEATURE, default
+   vhost-vdpa      vhost-vdpa kernel backend support
+   spice           spice
+   rbd             rados block device (rbd)
++  vitastor        vitastor block device
+   libiscsi        iscsi support
+   libnfs          nfs support
+   smartcard       smartcard support (libcacard)
+@@ -3719,6 +3725,27 @@ EOF
+ fi
+ 
+ ##########################################
++# vitastor probe
++if test "$vitastor" != "no" ; then
++  cat > $TMPC <<EOF
++#include <vitastor_c.h>
++int main(void) {
++  vitastor_c_create_qemu(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
++  return 0;
++}
++EOF
++  vitastor_libs="-lvitastor_client"
++  if compile_prog "" "$vitastor_libs" ; then
++    vitastor=yes
++  else
++    if test "$vitastor" = "yes" ; then
++      feature_not_found "vitastor block device" "Install vitastor-client-dev"
++    fi
++    vitastor=no
++  fi
++fi
++
++##########################################
+ # libssh probe
+ if test "$libssh" != "no" ; then
+   if $pkg_config --exists libssh; then
+@@ -6456,6 +6483,10 @@ if test "$rbd" = "yes" ; then
+   echo "CONFIG_RBD=y" >> $config_host_mak
+   echo "RBD_LIBS=$rbd_libs" >> $config_host_mak
+ fi
++if test "$vitastor" = "yes" ; then
++  echo "CONFIG_VITASTOR=y" >> $config_host_mak
++  echo "VITASTOR_LIBS=$vitastor_libs" >> $config_host_mak
++fi
+ 
+ echo "CONFIG_COROUTINE_BACKEND=$coroutine" >> $config_host_mak
+ if test "$coroutine_pool" = "yes" ; then
+Index: qemu-5.2+dfsg/meson.build
+===================================================================
+--- qemu-5.2+dfsg.orig/meson.build
++++ qemu-5.2+dfsg/meson.build
+@@ -596,6 +596,10 @@ rbd = not_found
+ if 'CONFIG_RBD' in config_host
+   rbd = declare_dependency(link_args: config_host['RBD_LIBS'].split())
+ endif
++vitastor = not_found
++if 'CONFIG_VITASTOR' in config_host
++  vitastor = declare_dependency(link_args: config_host['VITASTOR_LIBS'].split())
++endif
+ glusterfs = not_found
+ if 'CONFIG_GLUSTERFS' in config_host
+   glusterfs = declare_dependency(compile_args: config_host['GLUSTERFS_CFLAGS'].split(),
+@@ -2145,6 +2149,7 @@ endif
+ # TODO: add back protocol and server version
+ summary_info += {'spice support':     config_host.has_key('CONFIG_SPICE')}
+ summary_info += {'rbd support':       config_host.has_key('CONFIG_RBD')}
++summary_info += {'vitastor support':  config_host.has_key('CONFIG_VITASTOR')}
+ summary_info += {'xfsctl support':    config_host.has_key('CONFIG_XFS')}
+ summary_info += {'smartcard support': config_host.has_key('CONFIG_SMARTCARD')}
+ summary_info += {'U2F support':       u2f.found()}

rpm/build-tarball.sh

@@ -24,4 +24,4 @@ rm fio
 mv fio-copy fio
 FIO=`rpm -qi fio | perl -e 'while(<>) { /^Epoch[\s:]+(\S+)/ && print "$1:"; /^Version[\s:]+(\S+)/ && print $1; /^Release[\s:]+(\S+)/ && print "-$1"; }'`
 perl -i -pe 's/(Requires:\s*fio)([^\n]+)?/$1 = '$FIO'/' $VITASTOR/rpm/vitastor-el$EL.spec
-tar --transform 's#^#vitastor-0.9.2/#' --exclude 'rpm/*.rpm' -czf $VITASTOR/../vitastor-0.9.2$(rpm --eval '%dist').tar.gz *
+tar --transform 's#^#vitastor-1.0.0/#' --exclude 'rpm/*.rpm' -czf $VITASTOR/../vitastor-1.0.0$(rpm --eval '%dist').tar.gz *

rpm/qemu-kvm-4.2-el7.spec.patch

@@ -22,7 +22,7 @@
  Name: qemu-kvm
  Version: 4.2.0
 -Release: 29.vitastor%{?dist}.6
-+Release: 32.vitastor%{?dist}.6
++Release: 34.vitastor%{?dist}.6
  # Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
  Epoch: 15
  License: GPLv2 and GPLv2+ and CC-BY

rpm/qemu-kvm-4.2-el8.spec.patch

@@ -13,7 +13,7 @@
  Name: qemu-kvm
  Version: 4.2.0
 -Release: 29%{?dist}.6
-+Release: 32.vitastor%{?dist}.6
++Release: 33.vitastor%{?dist}.6
  # Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
  Epoch: 15
  License: GPLv2 and GPLv2+ and CC-BY

rpm/qemu-kvm-6.2-el8.spec.patch

@@ -0,0 +1,103 @@
+--- qemu-kvm-6.2.spec.orig	2023-07-18 13:52:57.636625440 +0000
++++ qemu-kvm-6.2.spec	2023-07-18 13:52:19.011683886 +0000
+@@ -73,6 +73,7 @@ Requires: %{name}-hw-usbredir = %{epoch}
+ %endif                                                           \
+ Requires: %{name}-block-iscsi = %{epoch}:%{version}-%{release}   \
+ Requires: %{name}-block-rbd = %{epoch}:%{version}-%{release}     \
++Requires: %{name}-block-vitastor = %{epoch}:%{version}-%{release}\
+ Requires: %{name}-block-ssh = %{epoch}:%{version}-%{release}
+ 
+ # Macro to properly setup RHEL/RHEV conflict handling
+@@ -83,7 +84,7 @@ Obsoletes: %1-rhev <= %{epoch}:%{version
+ Summary: QEMU is a machine emulator and virtualizer
+ Name: qemu-kvm
+ Version: 6.2.0
+-Release: 32%{?rcrel}%{?dist}
++Release: 32.vitastor%{?rcrel}%{?dist}
+ # Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
+ Epoch: 15
+ License: GPLv2 and GPLv2+ and CC-BY
+@@ -122,6 +123,7 @@ Source37: tests_data_acpi_pc_SSDT.dimmpx
+ Source38: tests_data_acpi_q35_FACP.slic
+ Source39: tests_data_acpi_q35_SSDT.dimmpxm
+ Source40: tests_data_acpi_virt_SSDT.memhp
++Source41: qemu-vitastor.c
+ 
+ Patch0001: 0001-redhat-Adding-slirp-to-the-exploded-tree.patch
+ Patch0005: 0005-Initial-redhat-build.patch
+@@ -652,6 +654,7 @@ Patch255: kvm-scsi-protect-req-aiocb-wit
+ Patch256: kvm-dma-helpers-prevent-dma_blk_cb-vs-dma_aio_cancel-rac.patch
+ # For bz#2090990 - qemu crash with error scsi_req_unref(SCSIRequest *): Assertion `req->refcount > 0' failed or scsi_dma_complete(void *, int): Assertion `r->req.aiocb != NULL' failed [8.7.0]
+ Patch257: kvm-virtio-scsi-reset-SCSI-devices-from-main-loop-thread.patch
++Patch258: qemu-6.2-vitastor.patch
+ 
+ BuildRequires: wget
+ BuildRequires: rpm-build
+@@ -689,6 +692,7 @@ BuildRequires: libcurl-devel
+ BuildRequires: libssh-devel
+ BuildRequires: librados-devel
+ BuildRequires: librbd-devel
++BuildRequires: vitastor-client-devel
+ %if %{have_gluster}
+ # For gluster block driver
+ BuildRequires: glusterfs-api-devel
+@@ -926,6 +930,14 @@ Install this package if you want to acce
+ using the rbd protocol.
+ 
+ 
++%package  block-vitastor
++Summary: QEMU Vitastor block driver
++Requires: %{name}-common%{?_isa} = %{epoch}:%{version}-%{release}
++
++%description block-vitastor
++This package provides the additional Vitastor block driver for QEMU.
++
++
+ %package  block-ssh
+ Summary: QEMU SSH block driver
+ Requires: %{name}-common%{?_isa} = %{epoch}:%{version}-%{release}
+@@ -979,6 +991,7 @@ This package provides usbredir support.
+ rm -fr slirp
+ mkdir slirp
+ %autopatch -p1
++cp %{SOURCE41} ./block/vitastor.c
+ 
+ %global qemu_kvm_build qemu_kvm_build
+ mkdir -p %{qemu_kvm_build}
+@@ -994,7 +1007,7 @@ cp -f %{SOURCE40} tests/data/acpi/virt/S
+ # --build-id option is used for giving info to the debug packages.
+ buildldflags="VL_LDFLAGS=-Wl,--build-id"
+ 
+-%global block_drivers_list qcow2,raw,file,host_device,nbd,iscsi,rbd,blkdebug,luks,null-co,nvme,copy-on-read,throttle
++%global block_drivers_list qcow2,raw,file,host_device,nbd,iscsi,rbd,vitastor,blkdebug,luks,null-co,nvme,copy-on-read,throttle
+ 
+ %if 0%{have_gluster}
+     %global block_drivers_list %{block_drivers_list},gluster
+@@ -1149,9 +1162,7 @@ pushd %{qemu_kvm_build}
+   --firmwarepath=%{_prefix}/share/qemu-firmware \
+   --meson="git" \
+   --target-list="%{buildarch}" \
+-  --block-drv-rw-whitelist=%{block_drivers_list} \
+   --audio-drv-list= \
+-  --block-drv-ro-whitelist=vmdk,vhdx,vpc,https,ssh \
+   --with-coroutine=ucontext \
+   --with-git=git \
+   --tls-priority=@QEMU,SYSTEM \
+@@ -1197,6 +1208,7 @@ pushd %{qemu_kvm_build}
+ %endif
+   --enable-pie \
+   --enable-rbd \
++  --enable-vitastor \
+ %if 0%{have_librdma}
+   --enable-rdma \
+ %endif
+@@ -1794,6 +1806,9 @@ sh %{_sysconfdir}/sysconfig/modules/kvm.
+ %files block-rbd
+ %{_libdir}/qemu-kvm/block-rbd.so
+ 
++%files block-vitastor
++%{_libdir}/qemu-kvm/block-vitastor.so
++
+ %files block-ssh
+ %{_libdir}/qemu-kvm/block-ssh.so
+ 

rpm/qemu-kvm-7.2-el9.spec.patch

@@ -0,0 +1,93 @@
+--- qemu-kvm-7.2.spec.orig	2023-06-22 13:56:19.000000000 +0000
++++ qemu-kvm-7.2.spec	2023-07-18 07:55:22.347090196 +0000
+@@ -100,8 +100,6 @@
+ %endif
+ 
+ %global target_list %{kvm_target}-softmmu
+-%global block_drivers_rw_list qcow2,raw,file,host_device,nbd,iscsi,rbd,blkdebug,luks,null-co,nvme,copy-on-read,throttle,compress
+-%global block_drivers_ro_list vdi,vmdk,vhdx,vpc,https
+ %define qemudocdir %{_docdir}/%{name}
+ %global firmwaredirs "%{_datadir}/qemu-firmware:%{_datadir}/ipxe/qemu:%{_datadir}/seavgabios:%{_datadir}/seabios"
+ 
+@@ -126,6 +124,7 @@ Requires: %{name}-device-usb-host = %{ep
+ Requires: %{name}-device-usb-redirect = %{epoch}:%{version}-%{release}   \
+ %endif                                                           \
+ Requires: %{name}-block-rbd = %{epoch}:%{version}-%{release}     \
++Requires: %{name}-block-vitastor = %{epoch}:%{version}-%{release}\
+ Requires: %{name}-audio-pa = %{epoch}:%{version}-%{release}
+ 
+ # Since SPICE is removed from RHEL-9, the following Obsoletes:
+@@ -148,7 +147,7 @@ Obsoletes: %{name}-block-ssh <= %{epoch}
+ Summary: QEMU is a machine emulator and virtualizer
+ Name: qemu-kvm
+ Version: 7.2.0
+-Release: 14%{?rcrel}%{?dist}%{?cc_suffix}.1
++Release: 14.vitastor%{?rcrel}%{?dist}%{?cc_suffix}.1
+ # Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
+ # Epoch 15 used for RHEL 8
+ # Epoch 17 used for RHEL 9 (due to release versioning offset in RHEL 8.5)
+@@ -171,6 +170,7 @@ Source28: 95-kvm-memlock.conf
+ Source30: kvm-s390x.conf
+ Source31: kvm-x86.conf
+ Source36: README.tests
++Source37: qemu-vitastor.c
+ 
+ 
+ Patch0004: 0004-Initial-redhat-build.patch
+@@ -418,6 +418,7 @@ Patch134: kvm-target-i386-Fix-BZHI-instr
+ Patch135: kvm-intel-iommu-fail-DEVIOTLB_UNMAP-without-dt-mode.patch
+ # For bz#2203745 - Disk detach is unsuccessful while the guest is still booting [rhel-9.2.0.z]
+ Patch136: kvm-acpi-pcihp-allow-repeating-hot-unplug-requests.patch
++Patch137: qemu-7.2-vitastor.patch
+ 
+ %if %{have_clang}
+ BuildRequires: clang
+@@ -449,6 +450,7 @@ BuildRequires: libcurl-devel
+ %if %{have_block_rbd}
+ BuildRequires: librbd-devel
+ %endif
++BuildRequires: vitastor-client-devel
+ # We need both because the 'stap' binary is probed for by configure
+ BuildRequires: systemtap
+ BuildRequires: systemtap-sdt-devel
+@@ -642,6 +644,14 @@ using the rbd protocol.
+ %endif
+ 
+ 
++%package  block-vitastor
++Summary: QEMU Vitastor block driver
++Requires: %{name}-common%{?_isa} = %{epoch}:%{version}-%{release}
++
++%description block-vitastor
++This package provides the additional Vitastor block driver for QEMU.
++
++
+ %package  audio-pa
+ Summary: QEMU PulseAudio audio driver
+ Requires: %{name}-common%{?_isa} = %{epoch}:%{version}-%{release}
+@@ -719,6 +729,7 @@ This package provides usbredir support.
+ %prep
+ %setup -q -n qemu-%{version}%{?rcstr}
+ %autopatch -p1
++cp %{SOURCE37} ./block/vitastor.c
+ 
+ %global qemu_kvm_build qemu_kvm_build
+ mkdir -p %{qemu_kvm_build}
+@@ -946,6 +957,7 @@ run_configure \
+ %if %{have_block_rbd}
+   --enable-rbd \
+ %endif
++  --enable-vitastor \
+ %if %{have_librdma}
+   --enable-rdma \
+ %endif
+@@ -1426,6 +1438,9 @@ useradd -r -u 107 -g qemu -G kvm -d / -s
+ %files block-rbd
+ %{_libdir}/%{name}/block-rbd.so
+ %endif
++%files block-vitastor
++%{_libdir}/%{name}/block-vitastor.so
++
+ %files audio-pa
+ %{_libdir}/%{name}/audio-pa.so
+ 

rpm/vitastor-el7.Dockerfile

@@ -35,7 +35,7 @@ ADD . /root/vitastor
 RUN set -e; \
     cd /root/vitastor/rpm; \
     sh build-tarball.sh; \
-    cp /root/vitastor-0.9.2.el7.tar.gz ~/rpmbuild/SOURCES; \
+    cp /root/vitastor-1.0.0.el7.tar.gz ~/rpmbuild/SOURCES; \
     cp vitastor-el7.spec ~/rpmbuild/SPECS/vitastor.spec; \
     cd ~/rpmbuild/SPECS/; \
     rpmbuild -ba vitastor.spec; \

rpm/vitastor-el7.spec

@@ -1,11 +1,11 @@
 Name:           vitastor
-Version:        0.9.2
+Version:        1.0.0
 Release:        1%{?dist}
 Summary:        Vitastor, a fast software-defined clustered block storage
 
 License:        Vitastor Network Public License 1.1
 URL:            https://vitastor.io/
-Source0:        vitastor-0.9.2.el7.tar.gz
+Source0:        vitastor-1.0.0.el7.tar.gz
 
 BuildRequires:  liburing-devel >= 0.6
 BuildRequires:  gperftools-devel

rpm/vitastor-el8.Dockerfile

@@ -35,7 +35,7 @@ ADD . /root/vitastor
 RUN set -e; \
     cd /root/vitastor/rpm; \
     sh build-tarball.sh; \
-    cp /root/vitastor-0.9.2.el8.tar.gz ~/rpmbuild/SOURCES; \
+    cp /root/vitastor-1.0.0.el8.tar.gz ~/rpmbuild/SOURCES; \
     cp vitastor-el8.spec ~/rpmbuild/SPECS/vitastor.spec; \
     cd ~/rpmbuild/SPECS/; \
     rpmbuild -ba vitastor.spec; \

rpm/vitastor-el8.spec

@@ -1,11 +1,11 @@
 Name:           vitastor
-Version:        0.9.2
+Version:        1.0.0
 Release:        1%{?dist}
 Summary:        Vitastor, a fast software-defined clustered block storage
 
 License:        Vitastor Network Public License 1.1
 URL:            https://vitastor.io/
-Source0:        vitastor-0.9.2.el8.tar.gz
+Source0:        vitastor-1.0.0.el8.tar.gz
 
 BuildRequires:  liburing-devel >= 0.6
 BuildRequires:  gperftools-devel

rpm/vitastor-el9.Dockerfile

@@ -18,7 +18,7 @@ ADD . /root/vitastor
 RUN set -e; \
     cd /root/vitastor/rpm; \
     sh build-tarball.sh; \
-    cp /root/vitastor-0.9.2.el9.tar.gz ~/rpmbuild/SOURCES; \
+    cp /root/vitastor-1.0.0.el9.tar.gz ~/rpmbuild/SOURCES; \
     cp vitastor-el9.spec ~/rpmbuild/SPECS/vitastor.spec; \
     cd ~/rpmbuild/SPECS/; \
     rpmbuild -ba vitastor.spec; \

rpm/vitastor-el9.spec

@@ -1,11 +1,11 @@
 Name:           vitastor
-Version:        0.9.2
+Version:        1.0.0
 Release:        1%{?dist}
 Summary:        Vitastor, a fast software-defined clustered block storage
 
 License:        Vitastor Network Public License 1.1
 URL:            https://vitastor.io/
-Source0:        vitastor-0.9.2.el9.tar.gz
+Source0:        vitastor-1.0.0.el9.tar.gz
 
 BuildRequires:  liburing-devel >= 0.6
 BuildRequires:  gperftools-devel

src/CMakeLists.txt

@@ -16,7 +16,7 @@ if("${CMAKE_INSTALL_PREFIX}" MATCHES "^/usr/local/?$")
 	set(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}")
 endif()
 
-add_definitions(-DVERSION="0.9.2")
+add_definitions(-DVERSION="1.0.0")
 add_definitions(-Wall -Wno-sign-compare -Wno-comment -Wno-parentheses -Wno-pointer-arith -fdiagnostics-color=always -I ${CMAKE_SOURCE_DIR}/src)
 if (${WITH_ASAN})
 	add_definitions(-fsanitize=address -fno-omit-frame-pointer)
@@ -56,11 +56,6 @@ if (ISAL_LIBRARIES)
 	add_definitions(-DWITH_ISAL)
 endif (ISAL_LIBRARIES)
 
-find_package(OpenSSL)
-if (OPENSSL_FOUND)
-	add_definitions(-DWITH_OPENSSL)
-endif (OPENSSL_FOUND)
-
 add_custom_target(build_tests)
 add_custom_target(test
 	COMMAND

src/addr_util.cpp

@@ -19,8 +19,8 @@ bool string_to_addr(std::string str, bool parse_port, int default_port, struct s
         if (p != std::string::npos && !(str.length() > 0 && str[p-1] == ']')) // "[ipv6]" which contains ':'
         {
             char null_byte = 0;
-            int n = sscanf(str.c_str()+p+1, "%d%c", &default_port, &null_byte);
-            if (n != 1 || default_port >= 0x10000)
+            int scanned = sscanf(str.c_str()+p+1, "%d%c", &default_port, &null_byte);
+            if (scanned != 1 || default_port >= 0x10000)
                 return false;
             str = str.substr(0, p);
         }

src/allocator.cpp

@@ -143,34 +143,83 @@ uint64_t allocator::get_free_count()
     return free;
 }
 
+// FIXME: Move to utils?
 void bitmap_set(void *bitmap, uint64_t start, uint64_t len, uint64_t bitmap_granularity)
 {
-    if (start == 0)
+    if (start == 0 && len == 32*bitmap_granularity)
+        *((uint32_t*)bitmap) = UINT32_MAX;
+    else if (start == 0 && len == 64*bitmap_granularity)
+        *((uint64_t*)bitmap) = UINT64_MAX;
+    else
     {
-        if (len == 32*bitmap_granularity)
+        unsigned bit_start = start / bitmap_granularity;
+        unsigned bit_end = ((start + len) + bitmap_granularity - 1) / bitmap_granularity;
+        while (bit_start < bit_end)
         {
-            *((uint32_t*)bitmap) = UINT32_MAX;
-            return;
-        }
-        else if (len == 64*bitmap_granularity)
-        {
-            *((uint64_t*)bitmap) = UINT64_MAX;
-            return;
-        }
-    }
-    unsigned bit_start = start / bitmap_granularity;
-    unsigned bit_end = ((start + len) + bitmap_granularity - 1) / bitmap_granularity;
-    while (bit_start < bit_end)
-    {
-        if (!(bit_start & 7) && bit_end >= bit_start+8)
-        {
-            ((uint8_t*)bitmap)[bit_start / 8] = UINT8_MAX;
-            bit_start += 8;
-        }
-        else
-        {
-            ((uint8_t*)bitmap)[bit_start / 8] |= 1 << (bit_start % 8);
-            bit_start++;
+            if (!(bit_start & 7) && bit_end >= bit_start+8)
+            {
+                ((uint8_t*)bitmap)[bit_start / 8] = UINT8_MAX;
+                bit_start += 8;
+            }
+            else
+            {
+                ((uint8_t*)bitmap)[bit_start / 8] |= 1 << (bit_start % 8);
+                bit_start++;
+            }
         }
     }
 }
+
+void bitmap_clear(void *bitmap, uint64_t start, uint64_t len, uint64_t bitmap_granularity)
+{
+    if (start == 0 && len == 32*bitmap_granularity)
+        *((uint32_t*)bitmap) = 0;
+    else if (start == 0 && len == 64*bitmap_granularity)
+        *((uint64_t*)bitmap) = 0;
+    else
+    {
+        unsigned bit_start = start / bitmap_granularity;
+        unsigned bit_end = ((start + len) + bitmap_granularity - 1) / bitmap_granularity;
+        while (bit_start < bit_end)
+        {
+            if (!(bit_start & 7) && bit_end >= bit_start+8)
+            {
+                ((uint8_t*)bitmap)[bit_start / 8] = 0;
+                bit_start += 8;
+            }
+            else
+            {
+                ((uint8_t*)bitmap)[bit_start / 8] &= (0xFF ^ (1 << (bit_start % 8)));
+                bit_start++;
+            }
+        }
+    }
+}
+
+bool bitmap_check(void *bitmap, uint64_t start, uint64_t len, uint64_t bitmap_granularity)
+{
+    bool r = false;
+    if (start == 0 && len == 32*bitmap_granularity)
+        r = !!*((uint32_t*)bitmap);
+    else if (start == 0 && len == 64*bitmap_granularity)
+        r = !!*((uint64_t*)bitmap);
+    else
+    {
+        unsigned bit_start = start / bitmap_granularity;
+        unsigned bit_end = ((start + len) + bitmap_granularity - 1) / bitmap_granularity;
+        while (bit_start < bit_end)
+        {
+            if (!(bit_start & 7) && bit_end >= bit_start+8)
+            {
+                r = r || !!((uint8_t*)bitmap)[bit_start / 8];
+                bit_start += 8;
+            }
+            else
+            {
+                r = r || (((uint8_t*)bitmap)[bit_start / 8] & (1 << (bit_start % 8)));
+                bit_start++;
+            }
+        }
+    }
+    return r;
+}

src/allocator.h

@@ -23,3 +23,5 @@ public:
 };
 
 void bitmap_set(void *bitmap, uint64_t start, uint64_t len, uint64_t bitmap_granularity);
+void bitmap_clear(void *bitmap, uint64_t start, uint64_t len, uint64_t bitmap_granularity);
+bool bitmap_check(void *bitmap, uint64_t start, uint64_t len, uint64_t bitmap_granularity);

src/blockstore.h

@@ -77,6 +77,7 @@ Output:
   -EINVAL = invalid input parameters
   -ENOENT = requested object/version does not exist for reads
   -ENOSPC = no space left in the store for writes
+  -EDOM = checksum error.
 - version = the version actually read or written
 
 ## BS_OP_DELETE

src/blockstore_disk.cpp

@@ -40,10 +40,31 @@ void blockstore_disk_t::parse_config(std::map<std::string, std::string> & config
     data_block_size = parse_size(config["block_size"]);
     journal_device = config["journal_device"];
     journal_offset = parse_size(config["journal_offset"]);
-    disk_alignment = strtoull(config["disk_alignment"].c_str(), NULL, 10);
-    journal_block_size = strtoull(config["journal_block_size"].c_str(), NULL, 10);
-    meta_block_size = strtoull(config["meta_block_size"].c_str(), NULL, 10);
-    bitmap_granularity = strtoull(config["bitmap_granularity"].c_str(), NULL, 10);
+    disk_alignment = parse_size(config["disk_alignment"]);
+    journal_block_size = parse_size(config["journal_block_size"]);
+    meta_block_size = parse_size(config["meta_block_size"]);
+    bitmap_granularity = parse_size(config["bitmap_granularity"]);
+    meta_format = stoull_full(config["meta_format"]);
+    cached_io_data = config["cached_io_data"] == "true" || config["cached_io_data"] == "yes" || config["cached_io_data"] == "1";
+    cached_io_meta = cached_io_data && (meta_device == data_device || meta_device == "") &&
+        config.find("cached_io_meta") == config.end() ||
+        config["cached_io_meta"] == "true" || config["cached_io_meta"] == "yes" || config["cached_io_meta"] == "1";
+    cached_io_journal = cached_io_meta && (journal_device == meta_device || journal_device == "") &&
+        config.find("cached_io_journal") == config.end() ||
+        config["cached_io_journal"] == "true" || config["cached_io_journal"] == "yes" || config["cached_io_journal"] == "1";
+    if (config["data_csum_type"] == "crc32c")
+    {
+        data_csum_type = BLOCKSTORE_CSUM_CRC32C;
+    }
+    else if (config["data_csum_type"] == "" || config["data_csum_type"] == "none")
+    {
+        data_csum_type = BLOCKSTORE_CSUM_NONE;
+    }
+    else
+    {
+        throw std::runtime_error("data_csum_type="+config["data_csum_type"]+" is unsupported, only \"crc32c\" and \"none\" are supported");
+    }
+    csum_block_size = parse_size(config["csum_block_size"]);
     // Validate
     if (!data_block_size)
     {
@@ -91,7 +112,23 @@ void blockstore_disk_t::parse_config(std::map<std::string, std::string> & config
     }
     if (data_block_size % bitmap_granularity)
     {
-        throw std::runtime_error("Block size must be a multiple of sparse write tracking granularity");
+        throw std::runtime_error("Data block size must be a multiple of sparse write tracking granularity");
+    }
+    if (!data_csum_type)
+    {
+        csum_block_size = 0;
+    }
+    else if (!csum_block_size)
+    {
+        csum_block_size = bitmap_granularity;
+    }
+    if (csum_block_size && (csum_block_size % bitmap_granularity))
+    {
+        throw std::runtime_error("Checksum block size must be a multiple of sparse write tracking granularity");
+    }
+    if (csum_block_size && (data_block_size % csum_block_size))
+    {
+        throw std::runtime_error("Checksum block size must be a divisor of data block size");
     }
     if (meta_device == "")
     {
@@ -110,7 +147,9 @@ void blockstore_disk_t::parse_config(std::map<std::string, std::string> & config
         throw std::runtime_error("journal_offset must be a multiple of journal_block_size = "+std::to_string(journal_block_size));
     }
     clean_entry_bitmap_size = data_block_size / bitmap_granularity / 8;
-    clean_entry_size = sizeof(clean_disk_entry) + 2*clean_entry_bitmap_size;
+    clean_dyn_size = clean_entry_bitmap_size*2 + (csum_block_size
+        ? data_block_size/csum_block_size*(data_csum_type & 0xFF) : 0);
+    clean_entry_size = sizeof(clean_disk_entry) + clean_dyn_size + 4 /*entry_csum*/;
 }
 
 void blockstore_disk_t::calc_lengths(bool skip_meta_check)
@@ -160,6 +199,25 @@ void blockstore_disk_t::calc_lengths(bool skip_meta_check)
     // required metadata size
     block_count = data_len / data_block_size;
     meta_len = (1 + (block_count - 1 + meta_block_size / clean_entry_size) / (meta_block_size / clean_entry_size)) * meta_block_size;
+    if (meta_format == BLOCKSTORE_META_FORMAT_V1 ||
+        !meta_format && !skip_meta_check && meta_area_size < meta_len && !data_csum_type)
+    {
+        uint64_t clean_entry_v0_size = sizeof(clean_disk_entry) + 2*clean_entry_bitmap_size;
+        uint64_t meta_v0_len = (1 + (block_count - 1 + meta_block_size / clean_entry_v0_size)
+            / (meta_block_size / clean_entry_v0_size)) * meta_block_size;
+        if (meta_format == BLOCKSTORE_META_FORMAT_V1 || meta_area_size >= meta_v0_len)
+        {
+            // Old metadata fits.
+            printf("Warning: Using old metadata format without checksums because the new format doesn't fit into provided area\n");
+            clean_entry_size = clean_entry_v0_size;
+            meta_len = meta_v0_len;
+            meta_format = BLOCKSTORE_META_FORMAT_V1;
+        }
+        else
+            meta_format = BLOCKSTORE_META_FORMAT_V2;
+    }
+    else
+        meta_format = BLOCKSTORE_META_FORMAT_V2;
     if (!skip_meta_check && meta_area_size < meta_len)
     {
         throw std::runtime_error("Metadata area is too small, need at least "+std::to_string(meta_len)+" bytes");
@@ -216,7 +274,7 @@ static void check_size(int fd, uint64_t *size, uint64_t *sectsize, std::string n
 
 void blockstore_disk_t::open_data()
 {
-    data_fd = open(data_device.c_str(), O_DIRECT|O_RDWR);
+    data_fd = open(data_device.c_str(), (cached_io_data ? O_SYNC : O_DIRECT) | O_RDWR);
     if (data_fd == -1)
     {
         throw std::runtime_error("Failed to open data device "+data_device+": "+std::string(strerror(errno)));
@@ -241,9 +299,9 @@ void blockstore_disk_t::open_data()
 
 void blockstore_disk_t::open_meta()
 {
-    if (meta_device != data_device)
+    if (meta_device != data_device || cached_io_meta != cached_io_data)
     {
-        meta_fd = open(meta_device.c_str(), O_DIRECT|O_RDWR);
+        meta_fd = open(meta_device.c_str(), (cached_io_meta ? O_SYNC : O_DIRECT) | O_RDWR);
         if (meta_fd == -1)
         {
             throw std::runtime_error("Failed to open metadata device "+meta_device+": "+std::string(strerror(errno)));
@@ -253,7 +311,7 @@ void blockstore_disk_t::open_meta()
         {
             throw std::runtime_error("meta_offset exceeds device size = "+std::to_string(meta_device_size));
         }
-        if (!disable_flock && flock(meta_fd, LOCK_EX|LOCK_NB) != 0)
+        if (!disable_flock && meta_device != data_device && flock(meta_fd, LOCK_EX|LOCK_NB) != 0)
         {
             throw std::runtime_error(std::string("Failed to lock metadata device: ") + strerror(errno));
         }
@@ -279,15 +337,15 @@ void blockstore_disk_t::open_meta()
 
 void blockstore_disk_t::open_journal()
 {
-    if (journal_device != meta_device)
+    if (journal_device != meta_device || cached_io_journal != cached_io_meta)
     {
-        journal_fd = open(journal_device.c_str(), O_DIRECT|O_RDWR);
+        journal_fd = open(journal_device.c_str(), (cached_io_journal ? O_SYNC : O_DIRECT) | O_RDWR);
         if (journal_fd == -1)
         {
             throw std::runtime_error("Failed to open journal device "+journal_device+": "+std::string(strerror(errno)));
         }
         check_size(journal_fd, &journal_device_size, &journal_device_sect, "journal device");
-        if (!disable_flock && flock(journal_fd, LOCK_EX|LOCK_NB) != 0)
+        if (!disable_flock && journal_device != meta_device && flock(journal_fd, LOCK_EX|LOCK_NB) != 0)
         {
             throw std::runtime_error(std::string("Failed to lock journal device: ") + strerror(errno));
         }

src/blockstore_disk.h

@@ -8,6 +8,10 @@
 #include <string>
 #include <map>
 
+#define BLOCKSTORE_CSUM_NONE 0
+// Lower byte of checksum type is its length
+#define BLOCKSTORE_CSUM_CRC32C 0x104
+
 struct blockstore_disk_t
 {
     std::string data_device, meta_device, journal_device;
@@ -21,17 +25,23 @@ struct blockstore_disk_t
     uint64_t meta_block_size = 4096;
     // Sparse write tracking granularity. 4 KB is a good choice. Must be a multiple of disk_alignment
     uint64_t bitmap_granularity = 4096;
+    // Data checksum type, BLOCKSTORE_CSUM_NONE or BLOCKSTORE_CSUM_CRC32C
+    uint32_t data_csum_type = BLOCKSTORE_CSUM_NONE;
+    // Checksum block size, must be a multiple of bitmap_granularity
+    uint32_t csum_block_size = 4096;
     // By default, Blockstore locks all opened devices exclusively. This option can be used to disable locking
     bool disable_flock = false;
+    // Use Linux page cache for reads and writes, i.e. open FDs with O_SYNC instead of O_DIRECT
+    bool cached_io_data = false, cached_io_meta = false, cached_io_journal = false;
 
     int meta_fd = -1, data_fd = -1, journal_fd = -1;
-    uint64_t meta_offset, meta_device_sect, meta_device_size, meta_len;
+    uint64_t meta_offset, meta_device_sect, meta_device_size, meta_len, meta_format = 0;
     uint64_t data_offset, data_device_sect, data_device_size, data_len;
     uint64_t journal_offset, journal_device_sect, journal_device_size, journal_len;
 
     uint32_t block_order;
     uint64_t block_count;
-    uint32_t clean_entry_bitmap_size = 0, clean_entry_size = 0;
+    uint32_t clean_entry_bitmap_size = 0, clean_entry_size = 0, clean_dyn_size = 0;
 
     void parse_config(std::map<std::string, std::string> & config);
     void open_data();
@@ -39,4 +49,13 @@ struct blockstore_disk_t
     void open_journal();
     void calc_lengths(bool skip_meta_check = false);
     void close_all();
+
+    inline uint64_t dirty_dyn_size(uint64_t offset, uint64_t len)
+    {
+        // Checksums may be partial if write is not aligned with csum_block_size
+        return clean_entry_bitmap_size + (csum_block_size && len > 0
+            ? ((offset+len+csum_block_size-1)/csum_block_size - offset/csum_block_size)
+                * (data_csum_type & 0xFF)
+            : 0);
+    }
 };

src/blockstore_flush.h

@@ -1,10 +1,22 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)
 
+#define COPY_BUF_JOURNAL 1
+#define COPY_BUF_DATA 2
+#define COPY_BUF_ZERO 4
+#define COPY_BUF_CSUM_FILL 8
+#define COPY_BUF_COALESCED 16
+#define COPY_BUF_META_BLOCK 32
+#define COPY_BUF_JOURNALED_BIG 64
+
 struct copy_buffer_t
 {
-    uint64_t offset, len;
+    int copy_flags;
+    uint64_t offset, len, disk_offset;
+    uint64_t journal_sector; // only for reads: sector+1 if used and !journal.inmemory, otherwise 0
     void *buf;
+    uint8_t *csum_buf;
+    int *dyn_data;
 };
 
 struct meta_sector_t
@@ -37,7 +49,7 @@ class journal_flusher_co
 {
     blockstore_impl_t *bs;
     journal_flusher_t *flusher;
-    int wait_state, wait_count;
+    int wait_state, wait_count, wait_journal_count;
     struct io_uring_sqe *sqe;
     struct ring_data_t *data;
 
@@ -46,28 +58,39 @@ class journal_flusher_co
     obj_ver_id cur;
     std::map<obj_ver_id, dirty_entry>::iterator dirty_it, dirty_start, dirty_end;
     std::map<object_id, uint64_t>::iterator repeat_it;
-    std::function<void(ring_data_t*)> simple_callback_r, simple_callback_w;
+    std::function<void(ring_data_t*)> simple_callback_r, simple_callback_rj, simple_callback_w;
 
     bool skip_copy, has_delete, has_writes;
     std::vector<copy_buffer_t> v;
     std::vector<copy_buffer_t>::iterator it;
+    int i;
+    bool fill_incomplete, cleared_incomplete;
+    int read_to_fill_incomplete;
     int copy_count;
-    uint64_t clean_loc, old_clean_loc;
+    uint64_t clean_loc, clean_ver, old_clean_loc, old_clean_ver;
     flusher_meta_write_t meta_old, meta_new;
     bool clean_init_bitmap;
     uint64_t clean_bitmap_offset, clean_bitmap_len;
-    void *new_clean_bitmap;
+    uint8_t *clean_init_dyn_ptr;
+    uint8_t *new_clean_bitmap;
 
     uint64_t new_trim_pos;
 
-    // local: scan_dirty()
-    uint64_t offset, end_offset, submit_offset, submit_len;
-
     friend class journal_flusher_t;
-    bool scan_dirty(int wait_base);
+    void scan_dirty();
+    bool read_dirty(int wait_base);
+    bool modify_meta_do_reads(int wait_base);
+    bool wait_meta_reads(int wait_base);
     bool modify_meta_read(uint64_t meta_loc, flusher_meta_write_t &wr, int wait_base);
+    bool clear_incomplete_csum_block_bits(int wait_base);
+    void calc_block_checksums(uint32_t *new_data_csums, bool skip_overwrites);
+    void update_metadata_entry();
+    bool write_meta_block(flusher_meta_write_t & meta_block, int wait_base);
     void update_clean_db();
+    void free_data_blocks();
     bool fsync_batch(bool fsync_meta, int wait_base);
+    bool trim_journal(int wait_base);
+    void free_buffers();
 public:
     journal_flusher_co();
     bool loop();
@@ -95,14 +118,16 @@ class journal_flusher_t
 
     std::map<uint64_t, meta_sector_t> meta_sectors;
     std::deque<object_id> flush_queue;
-    std::map<object_id, uint64_t> flush_versions;
+    std::map<object_id, uint64_t> flush_versions; // FIXME: consider unordered_map?
 
     bool try_find_older(std::map<obj_ver_id, dirty_entry>::iterator & dirty_end, obj_ver_id & cur);
+    bool try_find_other(std::map<obj_ver_id, dirty_entry>::iterator & dirty_end, obj_ver_id & cur);
 
 public:
     journal_flusher_t(blockstore_impl_t *bs);
     ~journal_flusher_t();
     void loop();
+    bool is_trim_wanted() { return trim_wanted; }
     bool is_active();
     void mark_trim_possible();
     void request_trim();
@@ -111,4 +136,5 @@ public:
     void unshift_flush(obj_ver_id oid, bool force);
     void remove_flush(object_id oid);
     void dump_diagnostics();
+    bool is_mutated(uint64_t clean_loc);
 };

src/blockstore_impl.cpp

@@ -13,6 +13,7 @@ blockstore_impl_t::blockstore_impl_t(blockstore_config_t & config, ring_loop_t *
     initialized = 0;
     parse_config(config, true);
     zero_object = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, dsk.data_block_size);
+    alloc_dyn_data = dsk.clean_dyn_size > sizeof(void*) || dsk.csum_block_size > 0;
     try
     {
         dsk.open_data();
@@ -38,8 +39,8 @@ blockstore_impl_t::~blockstore_impl_t()
     dsk.close_all();
     if (metadata_buffer)
         free(metadata_buffer);
-    if (clean_bitmap)
-        free(clean_bitmap);
+    if (clean_bitmaps)
+        free(clean_bitmaps);
 }
 
 bool blockstore_impl_t::is_started()
@@ -392,6 +393,7 @@ void blockstore_impl_t::init_op(blockstore_op_t *op)
 {
     // Call constructor without allocating memory. We'll call destructor before returning op back
     new ((void*)op->private_data) blockstore_op_private_t;
+    PRIV(op)->min_flushed_journal_sector = PRIV(op)->max_flushed_journal_sector = 0;
     PRIV(op)->wait_for = 0;
     PRIV(op)->op_state = 0;
     PRIV(op)->pending_ops = 0;

src/blockstore_impl.h

@@ -93,11 +93,10 @@
 
 // "VITAstor"
 #define BLOCKSTORE_META_MAGIC_V1 0x726F747341544956l
-#define BLOCKSTORE_META_VERSION_V1 1
+#define BLOCKSTORE_META_FORMAT_V1 1
+#define BLOCKSTORE_META_FORMAT_V2 2
 
 // metadata header (superblock)
-// FIXME: After adding the OSD superblock, add a key to metadata
-// and journal headers to check if they belong to the same OSD
 struct __attribute__((__packed__)) blockstore_meta_header_v1_t
 {
     uint64_t zero;
@@ -108,14 +107,29 @@ struct __attribute__((__packed__)) blockstore_meta_header_v1_t
     uint32_t bitmap_granularity;
 };
 
+struct __attribute__((__packed__)) blockstore_meta_header_v2_t
+{
+    uint64_t zero;
+    uint64_t magic;
+    uint64_t version;
+    uint32_t meta_block_size;
+    uint32_t data_block_size;
+    uint32_t bitmap_granularity;
+    uint32_t data_csum_type;
+    uint32_t csum_block_size;
+    uint32_t header_csum;
+};
+
 // 32 bytes = 24 bytes + block bitmap (4 bytes by default) + external attributes (also bitmap, 4 bytes by default)
 // per "clean" entry on disk with fixed metadata tables
-// FIXME: maybe add crc32's to metadata
 struct __attribute__((__packed__)) clean_disk_entry
 {
     object_id oid;
     uint64_t version;
     uint8_t bitmap[];
+    // Two more fields come after bitmap in metadata version 2:
+    // uint32_t data_csum[];
+    // uint32_t entry_csum;
 };
 
 // 32 = 16 + 16 bytes per "clean" entry in memory (object_id => clean_entry)
@@ -125,7 +139,7 @@ struct __attribute__((__packed__)) clean_entry
     uint64_t location;
 };
 
-// 64 = 24 + 40 bytes per dirty entry in memory (obj_ver_id => dirty_entry)
+// 64 = 24 + 40 bytes per dirty entry in memory (obj_ver_id => dirty_entry). Plus checksums
 struct __attribute__((__packed__)) dirty_entry
 {
     uint32_t state;
@@ -134,7 +148,7 @@ struct __attribute__((__packed__)) dirty_entry
     uint32_t offset;   // data offset within object (stripe)
     uint32_t len;      // data length
     uint64_t journal_sector; // journal sector used for this entry
-    void* bitmap;   // either external bitmap itself when it fits, or a pointer to it when it doesn't
+    void* dyn_data;    // dynamic data: external bitmap and data block checksums. may be a pointer to the in-memory journal
 };
 
 // - Sync must be submitted after previous writes/deletes (not before!)
@@ -163,12 +177,23 @@ struct __attribute__((__packed__)) dirty_entry
 // Suspend operation until there is some free space on the data device
 #define WAIT_FREE 5
 
-struct fulfill_read_t
+struct used_clean_obj_t
 {
-    uint64_t offset, len;
-    uint64_t journal_sector; // sector+1 if used and !journal.inmemory, otherwise 0
+    int refs;
+    bool was_freed; // was freed by a parallel flush?
+    bool was_changed; // was changed by a parallel flush?
 };
 
+// https://github.com/algorithm-ninja/cpp-btree
+// https://github.com/greg7mdp/sparsepp/ was used previously, but it was TERRIBLY slow after resizing
+// with sparsepp, random reads dropped to ~700 iops very fast with just as much as ~32k objects in the DB
+typedef btree::btree_map<object_id, clean_entry> blockstore_clean_db_t;
+typedef std::map<obj_ver_id, dirty_entry> blockstore_dirty_db_t;
+
+#include "blockstore_init.h"
+
+#include "blockstore_flush.h"
+
 #define PRIV(op) ((blockstore_op_private_t*)(op)->private_data)
 #define FINISH_OP(op) PRIV(op)->~blockstore_op_private_t(); std::function<void (blockstore_op_t*)>(op->callback)(op)
 
@@ -181,10 +206,11 @@ struct blockstore_op_private_t
     int op_state;
 
     // Read
-    std::vector<fulfill_read_t> read_vec;
+    uint64_t clean_block_used;
+    std::vector<copy_buffer_t> read_vec;
 
     // Sync, write
-    int min_flushed_journal_sector, max_flushed_journal_sector;
+    uint64_t min_flushed_journal_sector, max_flushed_journal_sector;
 
     // Write
     struct iovec iov_zerofill[3];
@@ -194,19 +220,8 @@ struct blockstore_op_private_t
 
     // Sync
     std::vector<obj_ver_id> sync_big_writes, sync_small_writes;
-    int sync_small_checked, sync_big_checked;
 };
 
-// https://github.com/algorithm-ninja/cpp-btree
-// https://github.com/greg7mdp/sparsepp/ was used previously, but it was TERRIBLY slow after resizing
-// with sparsepp, random reads dropped to ~700 iops very fast with just as much as ~32k objects in the DB
-typedef btree::btree_map<object_id, clean_entry> blockstore_clean_db_t;
-typedef std::map<obj_ver_id, dirty_entry> blockstore_dirty_db_t;
-
-#include "blockstore_init.h"
-
-#include "blockstore_flush.h"
-
 typedef uint32_t pool_id_t;
 typedef uint64_t pool_pg_id_t;
 
@@ -253,7 +268,7 @@ class blockstore_impl_t
 
     std::map<pool_id_t, pool_shard_settings_t> clean_db_settings;
     std::map<pool_pg_id_t, blockstore_clean_db_t> clean_db_shards;
-    uint8_t *clean_bitmap = NULL;
+    uint8_t *clean_bitmaps = NULL;
     blockstore_dirty_db_t dirty_db;
     std::vector<blockstore_op_t*> submit_queue;
     std::vector<obj_ver_id> unsynced_big_writes, unsynced_small_writes;
@@ -267,6 +282,10 @@ class blockstore_impl_t
     journal_flusher_t *flusher;
     int big_to_flush = 0;
     int write_iodepth = 0;
+    bool alloc_dyn_data = false;
+
+    // clean data blocks referenced by read operations
+    std::map<uint64_t, used_clean_obj_t> used_clean_objects;
 
     bool live = false, queue_stall = false;
     ring_loop_t *ringloop;
@@ -310,8 +329,30 @@ class blockstore_impl_t
 
     // Read
     int dequeue_read(blockstore_op_t *read_op);
-    int fulfill_read(blockstore_op_t *read_op, uint64_t &fulfilled, uint32_t item_start, uint32_t item_end,
-        uint32_t item_state, uint64_t item_version, uint64_t item_location, uint64_t journal_sector);
+    void find_holes(std::vector<copy_buffer_t> & read_vec, uint32_t item_start, uint32_t item_end,
+        std::function<int(int, bool, uint32_t, uint32_t)> callback);
+    int fulfill_read(blockstore_op_t *read_op,
+        uint64_t &fulfilled, uint32_t item_start, uint32_t item_end,
+        uint32_t item_state, uint64_t item_version, uint64_t item_location,
+        uint64_t journal_sector, uint8_t *csum, int *dyn_data);
+    bool fulfill_clean_read(blockstore_op_t *read_op, uint64_t & fulfilled,
+        uint8_t *clean_entry_bitmap, int *dyn_data,
+        uint32_t item_start, uint32_t item_end, uint64_t clean_loc, uint64_t clean_ver);
+    int fill_partial_checksum_blocks(std::vector<copy_buffer_t> & rv, uint64_t & fulfilled,
+        uint8_t *clean_entry_bitmap, int *dyn_data, bool from_journal, uint8_t *read_buf, uint64_t read_offset, uint64_t read_end);
+    int pad_journal_read(std::vector<copy_buffer_t> & rv, copy_buffer_t & cp,
+        uint64_t dirty_offset, uint64_t dirty_end, uint64_t dirty_loc, uint8_t *csum_ptr, int *dyn_data,
+        uint64_t offset, uint64_t submit_len, uint64_t & blk_begin, uint64_t & blk_end, uint8_t* & blk_buf);
+    bool read_range_fulfilled(std::vector<copy_buffer_t> & rv, uint64_t & fulfilled, uint8_t *read_buf,
+        uint8_t *clean_entry_bitmap, uint32_t item_start, uint32_t item_end);
+    bool read_checksum_block(blockstore_op_t *op, int rv_pos, uint64_t &fulfilled, uint64_t clean_loc);
+    uint8_t* read_clean_meta_block(blockstore_op_t *read_op, uint64_t clean_loc, int rv_pos);
+    bool verify_padded_checksums(uint8_t *clean_entry_bitmap, uint8_t *csum_buf, uint32_t offset,
+        iovec *iov, int n_iov, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb);
+    bool verify_journal_checksums(uint8_t *csums, uint32_t offset,
+        iovec *iov, int n_iov, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb);
+    bool verify_clean_padded_checksums(blockstore_op_t *op, uint64_t clean_loc, uint8_t *dyn_data, bool from_journal,
+        iovec *iov, int n_iov, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb);
     int fulfill_read_push(blockstore_op_t *op, void *buf, uint64_t offset, uint64_t len,
         uint32_t item_state, uint64_t item_version);
     void handle_read_event(ring_data_t *data, blockstore_op_t *op);
@@ -342,6 +383,7 @@ class blockstore_impl_t
     int continue_rollback(blockstore_op_t *op);
     void mark_rolled_back(const obj_ver_id & ov);
     void erase_dirty(blockstore_dirty_db_t::iterator dirty_start, blockstore_dirty_db_t::iterator dirty_end, uint64_t clean_loc);
+    void free_dirty_dyn_data(dirty_entry & e);
 
     // List
     void process_list(blockstore_op_t *op);

src/blockstore_init.cpp

@@ -77,13 +77,20 @@ resume_1:
     if (iszero((uint64_t*)metadata_buffer, bs->dsk.meta_block_size / sizeof(uint64_t)))
     {
         {
-            blockstore_meta_header_v1_t *hdr = (blockstore_meta_header_v1_t *)metadata_buffer;
+            blockstore_meta_header_v2_t *hdr = (blockstore_meta_header_v2_t *)metadata_buffer;
             hdr->zero = 0;
             hdr->magic = BLOCKSTORE_META_MAGIC_V1;
-            hdr->version = BLOCKSTORE_META_VERSION_V1;
+            hdr->version = bs->dsk.meta_format;
             hdr->meta_block_size = bs->dsk.meta_block_size;
             hdr->data_block_size = bs->dsk.data_block_size;
             hdr->bitmap_granularity = bs->dsk.bitmap_granularity;
+            if (bs->dsk.meta_format >= BLOCKSTORE_META_FORMAT_V2)
+            {
+                hdr->data_csum_type = bs->dsk.data_csum_type;
+                hdr->csum_block_size = bs->dsk.csum_block_size;
+                hdr->header_csum = 0;
+                hdr->header_csum = crc32c(0, hdr, sizeof(*hdr));
+            }
         }
         if (bs->readonly)
         {
@@ -109,28 +116,62 @@ resume_1:
     }
     else
     {
-        blockstore_meta_header_v1_t *hdr = (blockstore_meta_header_v1_t *)metadata_buffer;
-        if (hdr->zero != 0 ||
-            hdr->magic != BLOCKSTORE_META_MAGIC_V1 ||
-            hdr->version != BLOCKSTORE_META_VERSION_V1)
+        blockstore_meta_header_v2_t *hdr = (blockstore_meta_header_v2_t *)metadata_buffer;
+        if (hdr->zero != 0 || hdr->magic != BLOCKSTORE_META_MAGIC_V1 || hdr->version < BLOCKSTORE_META_FORMAT_V1)
         {
             printf(
-                "Metadata is corrupt or old version.\n"
-                " If this is a new OSD please zero out the metadata area before starting it.\n"
-                " If you need to upgrade from 0.5.x please request it via the issue tracker.\n"
+                "Metadata is corrupt or too old (pre-0.6.x).\n"
+                " If this is a new OSD, please zero out the metadata area before starting it.\n"
+                " If you need to upgrade from 0.5.x, convert metadata with vitastor-disk.\n"
+            );
+            exit(1);
+        }
+        if (hdr->version == BLOCKSTORE_META_FORMAT_V2)
+        {
+            uint32_t csum = hdr->header_csum;
+            hdr->header_csum = 0;
+            if (crc32c(0, hdr, sizeof(*hdr)) != csum)
+            {
+                printf("Metadata header is corrupt (checksum mismatch).\n");
+                exit(1);
+            }
+            hdr->header_csum = csum;
+            bs->dsk.meta_format = BLOCKSTORE_META_FORMAT_V2;
+        }
+        else if (hdr->version == BLOCKSTORE_META_FORMAT_V1)
+        {
+            hdr->data_csum_type = 0;
+            hdr->csum_block_size = 0;
+            hdr->header_csum = 0;
+            // Enable compatibility mode - entries without checksums
+            bs->dsk.clean_entry_size = sizeof(clean_disk_entry) + bs->dsk.clean_entry_bitmap_size*2;
+            bs->dsk.meta_len = (1 + (bs->dsk.block_count - 1 + bs->dsk.meta_block_size / bs->dsk.clean_entry_size)
+                / (bs->dsk.meta_block_size / bs->dsk.clean_entry_size)) * bs->dsk.meta_block_size;
+            bs->dsk.meta_format = BLOCKSTORE_META_FORMAT_V1;
+            printf("Warning: Starting with metadata in the old format without checksums, as stored on disk\n");
+        }
+        else if (hdr->version > BLOCKSTORE_META_FORMAT_V2)
+        {
+            printf(
+                "Metadata format is too new for me (stored version is %lu, max supported %u).\n",
+                hdr->version, BLOCKSTORE_META_FORMAT_V2
             );
             exit(1);
         }
         if (hdr->meta_block_size != bs->dsk.meta_block_size ||
             hdr->data_block_size != bs->dsk.data_block_size ||
-            hdr->bitmap_granularity != bs->dsk.bitmap_granularity)
+            hdr->bitmap_granularity != bs->dsk.bitmap_granularity ||
+            hdr->data_csum_type != bs->dsk.data_csum_type ||
+            hdr->csum_block_size != bs->dsk.csum_block_size)
         {
             printf(
                 "Configuration stored in metadata superblock"
-                " (meta_block_size=%u, data_block_size=%u, bitmap_granularity=%u)"
-                " differs from OSD configuration (%lu/%u/%lu).\n",
+                " (meta_block_size=%u, data_block_size=%u, bitmap_granularity=%u, data_csum_type=%u, csum_block_size=%u)"
+                " differs from OSD configuration (%lu/%u/%lu, %u/%u).\n",
                 hdr->meta_block_size, hdr->data_block_size, hdr->bitmap_granularity,
-                bs->dsk.meta_block_size, bs->dsk.data_block_size, bs->dsk.bitmap_granularity
+                hdr->data_csum_type, hdr->csum_block_size,
+                bs->dsk.meta_block_size, bs->dsk.data_block_size, bs->dsk.bitmap_granularity,
+                bs->dsk.data_csum_type, bs->dsk.csum_block_size
             );
             exit(1);
         }
@@ -279,12 +320,22 @@ bool blockstore_init_meta::handle_meta_block(uint8_t *buf, uint64_t entries_per_
     for (uint64_t i = 0; i < max_i; i++)
     {
         clean_disk_entry *entry = (clean_disk_entry*)(buf + i*bs->dsk.clean_entry_size);
-        if (!bs->inmemory_meta && bs->dsk.clean_entry_bitmap_size)
-        {
-            memcpy(bs->clean_bitmap + (done_cnt+i)*2*bs->dsk.clean_entry_bitmap_size, &entry->bitmap, 2*bs->dsk.clean_entry_bitmap_size);
-        }
         if (entry->oid.inode > 0)
         {
+            if (bs->dsk.meta_format >= BLOCKSTORE_META_FORMAT_V2)
+            {
+                // Check entry crc32
+                uint32_t *entry_csum = (uint32_t*)((uint8_t*)entry + bs->dsk.clean_entry_size - 4);
+                if (*entry_csum != crc32c(0, entry, bs->dsk.clean_entry_size - 4))
+                {
+                    printf("Metadata entry %lu is corrupt (checksum mismatch), skipping\n", done_cnt+i);
+                    continue;
+                }
+            }
+            if (!bs->inmemory_meta && bs->dsk.clean_entry_bitmap_size)
+            {
+                memcpy(bs->clean_bitmaps + (done_cnt+i) * 2 * bs->dsk.clean_entry_bitmap_size, &entry->bitmap, 2 * bs->dsk.clean_entry_bitmap_size);
+            }
             auto & clean_db = bs->clean_db_shard(entry->oid);
             auto clean_it = clean_db.find(entry->oid);
             if (clean_it == clean_db.end() || clean_it->second.version < entry->version)
@@ -440,7 +491,9 @@ resume_1:
             .size = sizeof(journal_entry_start),
             .reserved = 0,
             .journal_start = bs->journal.block_size,
-            .version = JOURNAL_VERSION,
+            .version = JOURNAL_VERSION_V2,
+            .data_csum_type = bs->dsk.data_csum_type,
+            .csum_block_size = bs->dsk.csum_block_size,
         };
         ((journal_entry_start*)submitted_buf)->crc32 = je_crc32((journal_entry*)submitted_buf);
         if (bs->readonly)
@@ -492,18 +545,36 @@ resume_1:
         if (je_start->magic != JOURNAL_MAGIC ||
             je_start->type != JE_START ||
             je_crc32((journal_entry*)je_start) != je_start->crc32 ||
-            je_start->size != sizeof(journal_entry_start) && je_start->size != JE_START_LEGACY_SIZE)
+            je_start->size != JE_START_V0_SIZE && je_start->size != JE_START_V1_SIZE && je_start->size != JE_START_V2_SIZE)
         {
             // Entry is corrupt
-            fprintf(stderr, "First entry of the journal is corrupt\n");
+            fprintf(stderr, "First entry of the journal is corrupt or unsupported\n");
             exit(1);
         }
-        if (je_start->size == JE_START_LEGACY_SIZE || je_start->version != JOURNAL_VERSION)
+        if (je_start->size == JE_START_V0_SIZE ||
+            (je_start->version != JOURNAL_VERSION_V1 || je_start->size != JE_START_V1_SIZE) &&
+            (je_start->version != JOURNAL_VERSION_V2 || je_start->size != JE_START_V2_SIZE))
         {
             fprintf(
-                stderr, "The code only supports journal version %d, but it is %lu on disk."
-                    " Please use the previous version to flush the journal before upgrading OSD\n",
-                JOURNAL_VERSION, je_start->size == JE_START_LEGACY_SIZE ? 0 : je_start->version
+                stderr, "The code only supports journal versions 2 and 1, but it is %lu on disk."
+                    " Please use vitastor-disk to rewrite the journal\n",
+                je_start->size == JE_START_V0_SIZE ? 0 : je_start->version
+            );
+            exit(1);
+        }
+        if (je_start->version == JOURNAL_VERSION_V1)
+        {
+            je_start->data_csum_type = 0;
+            je_start->csum_block_size = 0;
+        }
+        if (je_start->data_csum_type != bs->dsk.data_csum_type ||
+            je_start->csum_block_size != bs->dsk.csum_block_size)
+        {
+            printf(
+                "Configuration stored in journal superblock (data_csum_type=%u, csum_block_size=%u)"
+                " differs from OSD configuration (%u/%u).\n",
+                je_start->data_csum_type, je_start->csum_block_size,
+                bs->dsk.data_csum_type, bs->dsk.csum_block_size
             );
             exit(1);
         }
@@ -705,11 +776,14 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                     snprintf(err, 1024, "BUG: calculated journal data offset (%08lx) != stored journal data offset (%08lx)", location, je->small_write.data_offset);
                     throw std::runtime_error(err);
                 }
-                uint32_t data_crc32 = 0;
+                small_write_data.clear();
                 if (location >= done_pos && location+je->small_write.len <= done_pos+len)
                 {
                     // data is within this buffer
-                    data_crc32 = crc32c(0, (uint8_t*)buf + location - done_pos, je->small_write.len);
+                    small_write_data.push_back((iovec){
+                        .iov_base = (uint8_t*)buf + location - done_pos,
+                        .iov_len = je->small_write.len,
+                    });
                 }
                 else
                 {
@@ -724,7 +798,10 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                                 ? location+je->small_write.len : done[i].pos+done[i].len);
                             uint64_t part_begin = (location < done[i].pos ? done[i].pos : location);
                             covered += part_end - part_begin;
-                            data_crc32 = crc32c(data_crc32, (uint8_t*)done[i].buf + part_begin - done[i].pos, part_end - part_begin);
+                            small_write_data.push_back((iovec){
+                                .iov_base = (uint8_t*)done[i].buf + part_begin - done[i].pos,
+                                .iov_len = part_end - part_begin,
+                            });
                         }
                     }
                     if (covered < je->small_write.len)
@@ -734,12 +811,102 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         return 2;
                     }
                 }
-                if (data_crc32 != je->small_write.crc32_data)
+                bool data_csum_valid = true;
+                if (!bs->dsk.csum_block_size)
+                {
+                    uint32_t data_crc32 = 0;
+                    for (auto & sd: small_write_data)
+                    {
+                        data_crc32 = crc32c(data_crc32, sd.iov_base, sd.iov_len);
+                    }
+                    data_csum_valid = data_crc32 == je->small_write.crc32_data;
+                    if (!data_csum_valid)
+                    {
+                        printf(
+                            "Journal entry data is corrupt for small_write%s oid=%lx:%lx ver=%lu offset=%u len=%u - data crc32 %x != %x\n",
+                            je->type == JE_SMALL_WRITE_INSTANT ? "_instant" : "",
+                            je->small_write.oid.inode, je->small_write.oid.stripe, je->small_write.version,
+                            je->small_write.offset, je->small_write.len,
+                            data_crc32, je->small_write.crc32_data
+                        );
+                    }
+                }
+                else if (je->small_write.len > 0)
+                {
+                    // FIXME: deduplicate with disk_tool_journal.cpp
+                    // like in enqueue_write()
+                    uint32_t start = je->small_write.offset / bs->dsk.csum_block_size;
+                    uint32_t end = (je->small_write.offset+je->small_write.len-1) / bs->dsk.csum_block_size;
+                    uint32_t data_csum_size = (end-start+1) * (bs->dsk.data_csum_type & 0xFF);
+                    uint32_t required_size = sizeof(journal_entry_small_write) + bs->dsk.clean_entry_bitmap_size + data_csum_size;
+                    if (je->size != required_size)
+                    {
+                        printf(
+                            "Journal entry data has invalid size for small_write%s oid=%lx:%lx ver=%lu offset=%u len=%u - should be %u bytes but is %u bytes\n",
+                            je->type == JE_SMALL_WRITE_INSTANT ? "_instant" : "",
+                            je->small_write.oid.inode, je->small_write.oid.stripe, je->small_write.version,
+                            je->small_write.offset, je->small_write.len,
+                            required_size, je->size
+                        );
+                        data_csum_valid = false;
+                    }
+                    else
+                    {
+                        int sd_num = 0;
+                        size_t sd_pos = 0;
+                        uint32_t *block_csums = (uint32_t*)((uint8_t*)je + sizeof(journal_entry_small_write) + bs->dsk.clean_entry_bitmap_size);
+                        for (uint32_t pos = start; pos <= end; pos++, block_csums++)
+                        {
+                            size_t block_left = (pos == start
+                                ? (start == end
+                                    ? je->small_write.len
+                                    : bs->dsk.csum_block_size - je->small_write.offset%bs->dsk.csum_block_size)
+                                : (pos < end
+                                    ? bs->dsk.csum_block_size
+                                    : (je->small_write.offset + je->small_write.len)%bs->dsk.csum_block_size));
+                            if (pos > start && pos == end && block_left == 0)
+                            {
+                                // full last block
+                                block_left = bs->dsk.csum_block_size;
+                            }
+                            uint32_t block_crc32 = 0;
+                            while (block_left > 0)
+                            {
+                                assert(sd_num < small_write_data.size());
+                                if (small_write_data[sd_num].iov_len >= sd_pos+block_left)
+                                {
+                                    block_crc32 = crc32c(block_crc32, (uint8_t*)small_write_data[sd_num].iov_base+sd_pos, block_left);
+                                    sd_pos += block_left;
+                                    break;
+                                }
+                                else
+                                {
+                                    block_crc32 = crc32c(block_crc32, (uint8_t*)small_write_data[sd_num].iov_base+sd_pos, small_write_data[sd_num].iov_len-sd_pos);
+                                    block_left -= (small_write_data[sd_num].iov_len-sd_pos);
+                                    sd_pos = 0;
+                                    sd_num++;
+                                }
+                            }
+                            if (block_crc32 != *block_csums)
+                            {
+                                printf(
+                                    "Journal entry data is corrupt for small_write%s oid=%lx:%lx ver=%lu offset=%u len=%u - block %u crc32 %x != %x\n",
+                                    je->type == JE_SMALL_WRITE_INSTANT ? "_instant" : "",
+                                    je->small_write.oid.inode, je->small_write.oid.stripe, je->small_write.version,
+                                    je->small_write.offset, je->small_write.len,
+                                    pos, block_crc32, *block_csums
+                                );
+                                data_csum_valid = false;
+                                break;
+                            }
+                        }
+                    }
+                }
+                if (!data_csum_valid)
                 {
                     // journal entry is corrupt, stop here
                     // interesting thing is that we must clear the corrupt entry if we're not readonly,
                     // because we don't write next entries in the same journal block
-                    printf("Journal entry data is corrupt (data crc32 %x != %x)\n", data_crc32, je->small_write.crc32_data);
                     memset((uint8_t*)buf + proc_pos - done_pos + pos, 0, bs->journal.block_size - pos);
                     bs->journal.next_free = prev_free;
                     init_write_buf = (uint8_t*)buf + proc_pos - done_pos;
@@ -755,11 +922,14 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         .oid = je->small_write.oid,
                         .version = je->small_write.version,
                     };
-                    void *bmp = NULL;
-                    void *bmp_from = (uint8_t*)je + sizeof(journal_entry_small_write);
-                    if (bs->dsk.clean_entry_bitmap_size <= sizeof(void*))
+                    uint64_t dyn_size = bs->dsk.dirty_dyn_size(je->small_write.offset, je->small_write.len);
+                    void *dyn = NULL;
+                    void *dyn_from = (uint8_t*)je + sizeof(journal_entry_small_write);
+                    if (!bs->alloc_dyn_data)
                     {
-                        memcpy(&bmp, bmp_from, bs->dsk.clean_entry_bitmap_size);
+                        // Bitmap without checksum is only 4 bytes for 128k objects, save it inline
+                        // It can even contain 4 byte bitmap + 4 byte CRC32 for 4 kb writes :)
+                        memcpy(&dyn, dyn_from, dyn_size);
                     }
                     else
                     {
@@ -767,8 +937,9 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         // allocations for entry bitmaps. This can only be fixed by using
                         // a patched map with dynamic entry size, but not the btree_map,
                         // because it doesn't keep iterators valid all the time.
-                        bmp = malloc_or_die(bs->dsk.clean_entry_bitmap_size);
-                        memcpy(bmp, bmp_from, bs->dsk.clean_entry_bitmap_size);
+                        dyn = malloc_or_die(dyn_size+sizeof(int));
+                        *((int*)dyn) = 1;
+                        memcpy((uint8_t*)dyn+sizeof(int), dyn_from, dyn_size);
                     }
                     bs->dirty_db.emplace(ov, (dirty_entry){
                         .state = (BS_ST_SMALL_WRITE | BS_ST_SYNCED),
@@ -777,7 +948,7 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         .offset = je->small_write.offset,
                         .len = je->small_write.len,
                         .journal_sector = proc_pos,
-                        .bitmap = bmp,
+                        .dyn_data = dyn,
                     });
                     bs->journal.used_sectors[proc_pos]++;
 #ifdef BLOCKSTORE_DEBUG
@@ -836,11 +1007,13 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         .oid = je->big_write.oid,
                         .version = je->big_write.version,
                     };
-                    void *bmp = NULL;
-                    void *bmp_from = (uint8_t*)je + sizeof(journal_entry_big_write);
-                    if (bs->dsk.clean_entry_bitmap_size <= sizeof(void*))
+                    uint64_t dyn_size = bs->dsk.dirty_dyn_size(je->big_write.offset, je->big_write.len);
+                    void *dyn = NULL;
+                    void *dyn_from = (uint8_t*)je + sizeof(journal_entry_big_write);
+                    if (!bs->alloc_dyn_data)
                     {
-                        memcpy(&bmp, bmp_from, bs->dsk.clean_entry_bitmap_size);
+                        // Bitmap without checksum is only 4 bytes for 128k objects, save it inline
+                        memcpy(&dyn, dyn_from, dyn_size);
                     }
                     else
                     {
@@ -848,8 +1021,9 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         // allocations for entry bitmaps. This can only be fixed by using
                         // a patched map with dynamic entry size, but not the btree_map,
                         // because it doesn't keep iterators valid all the time.
-                        bmp = malloc_or_die(bs->dsk.clean_entry_bitmap_size);
-                        memcpy(bmp, bmp_from, bs->dsk.clean_entry_bitmap_size);
+                        dyn = malloc_or_die(dyn_size+sizeof(int));
+                        *((int*)dyn) = 1;
+                        memcpy((uint8_t*)dyn+sizeof(int), dyn_from, dyn_size);
                     }
                     auto dirty_it = bs->dirty_db.emplace(ov, (dirty_entry){
                         .state = (BS_ST_BIG_WRITE | BS_ST_SYNCED),
@@ -858,7 +1032,7 @@ int blockstore_init_journal::handle_journal_part(void *buf, uint64_t done_pos, u
                         .offset = je->big_write.offset,
                         .len = je->big_write.len,
                         .journal_sector = proc_pos,
-                        .bitmap = bmp,
+                        .dyn_data = dyn,
                     }).first;
                     if (bs->data_alloc->get(je->big_write.location >> bs->dsk.block_order))
                     {

src/blockstore_init.h

@@ -50,6 +50,7 @@ class blockstore_init_journal
     uint64_t next_free;
     std::vector<bs_init_journal_done> done;
     std::vector<obj_ver_id> double_allocs;
+    std::vector<iovec> small_write_data;
     uint64_t journal_pos = 0;
     uint64_t continue_pos = 0;
     void *init_write_buf = NULL;

src/blockstore_journal.cpp

@@ -17,6 +17,7 @@ blockstore_journal_check_t::blockstore_journal_check_t(blockstore_impl_t *bs)
 // Check if we can write <required> entries of <size> bytes and <data_after> data bytes after them to the journal
 int blockstore_journal_check_t::check_available(blockstore_op_t *op, int entries_required, int size, int data_after)
 {
+    uint64_t prev_next = next_sector;
     int required = entries_required;
     while (1)
     {
@@ -35,11 +36,19 @@ int blockstore_journal_check_t::check_available(blockstore_op_t *op, int entries
             }
             required -= fits;
             next_in_pos += fits * size;
-            sectors_to_write++;
+            if (next_sector != prev_next || !sectors_to_write)
+            {
+                // Except the previous call to this function
+                sectors_to_write++;
+            }
         }
         else if (bs->journal.sector_info[next_sector].dirty)
         {
-            sectors_to_write++;
+            if (next_sector != prev_next || !sectors_to_write)
+            {
+                // Except the previous call to this function
+                sectors_to_write++;
+            }
         }
         if (required <= 0)
         {
@@ -189,6 +198,7 @@ void blockstore_impl_t::prepare_journal_sector_write(int cur_sector, blockstore_
     priv->pending_ops++;
     if (!priv->min_flushed_journal_sector)
         priv->min_flushed_journal_sector = 1+cur_sector;
+    assert(priv->min_flushed_journal_sector <= journal.sector_count);
     priv->max_flushed_journal_sector = 1+cur_sector;
 }
 
@@ -289,3 +299,31 @@ void journal_t::dump_diagnostics()
         journal_used_it == used_sectors.end() ? 0 : journal_used_it->second
     );
 }
+
+static uint64_t zero_page[4096];
+
+uint32_t crc32c_pad(uint32_t prev_crc, const void *buf, size_t len, size_t left_pad, size_t right_pad)
+{
+    uint32_t r = prev_crc;
+    while (left_pad >= 4096)
+    {
+        r = crc32c(r, zero_page, 4096);
+        left_pad -= 4096;
+    }
+    if (left_pad > 0)
+        r = crc32c(r, zero_page, left_pad);
+    r = crc32c(r, buf, len);
+    while (right_pad >= 4096)
+    {
+        r = crc32c(r, zero_page, 4096);
+        right_pad -= 4096;
+    }
+    if (left_pad > 0)
+        r = crc32c(r, zero_page, right_pad);
+    return r;
+}
+
+uint32_t crc32c_nopad(uint32_t prev_crc, const void *buf, size_t len, size_t left_pad, size_t right_pad)
+{
+    return crc32c(0, buf, len);
+}

src/blockstore_journal.h

@@ -8,7 +8,8 @@
 
 #define MIN_JOURNAL_SIZE 4*1024*1024
 #define JOURNAL_MAGIC 0x4A33
-#define JOURNAL_VERSION 1
+#define JOURNAL_VERSION_V1 1
+#define JOURNAL_VERSION_V2 2
 #define JOURNAL_BUFFER_SIZE 4*1024*1024
 #define JOURNAL_ENTRY_HEADER_SIZE 16
 
@@ -32,7 +33,7 @@
 #define JE_BIG_WRITE_INSTANT   0x08
 #define JE_MAX         0x08
 
-// crc32c comes first to ease calculation and is equal to crc32()
+// crc32c comes first to ease calculation
 struct __attribute__((__packed__)) journal_entry_start
 {
     uint32_t crc32;
@@ -42,8 +43,12 @@ struct __attribute__((__packed__)) journal_entry_start
     uint32_t reserved;
     uint64_t journal_start;
     uint64_t version;
+    uint32_t data_csum_type;
+    uint32_t csum_block_size;
 };
-#define JE_START_LEGACY_SIZE 24
+#define JE_START_V0_SIZE 24
+#define JE_START_V1_SIZE 32
+#define JE_START_V2_SIZE 40
 
 struct __attribute__((__packed__)) journal_entry_small_write
 {
@@ -59,10 +64,12 @@ struct __attribute__((__packed__)) journal_entry_small_write
     // small_write entries contain <len> bytes of data which is stored in next sectors
     // data_offset is its offset within journal
     uint64_t data_offset;
-    uint32_t crc32_data;
+    uint32_t crc32_data; // zero when data_csum_type != 0
     // small_write and big_write entries are followed by the "external" bitmap
     // its size is dynamic and included in journal entry's <size> field
     uint8_t bitmap[];
+    // and then data checksums if data_csum_type != 0
+    // uint32_t data_crc32c[];
 };
 
 struct __attribute__((__packed__)) journal_entry_big_write
@@ -80,6 +87,8 @@ struct __attribute__((__packed__)) journal_entry_big_write
     // small_write and big_write entries are followed by the "external" bitmap
     // its size is dynamic and included in journal entry's <size> field
     uint8_t bitmap[];
+    // and then data checksums if data_csum_type != 0
+    // uint32_t data_crc32c[];
 };
 
 struct __attribute__((__packed__)) journal_entry_stable
@@ -218,3 +227,6 @@ struct blockstore_journal_check_t
 };
 
 journal_entry* prefill_single_journal_entry(journal_t & journal, uint16_t type, uint32_t size);
+
+uint32_t crc32c_pad(uint32_t prev_crc, const void *buf, size_t len, size_t left_pad, size_t right_pad);
+uint32_t crc32c_nopad(uint32_t prev_crc, const void *buf, size_t len, size_t left_pad, size_t right_pad);

src/blockstore_open.cpp

@@ -85,11 +85,13 @@ void blockstore_impl_t::parse_config(blockstore_config_t & config, bool init)
         immediate_commit = IMMEDIATE_SMALL;
     }
     metadata_buf_size = strtoull(config["meta_buf_size"].c_str(), NULL, 10);
-    inmemory_meta = config["inmemory_metadata"] != "false";
+    inmemory_meta = config["inmemory_metadata"] != "false" && config["inmemory_metadata"] != "0" &&
+        config["inmemory_metadata"] != "no";
     journal.sector_count = strtoull(config["journal_sector_buffer_count"].c_str(), NULL, 10);
     journal.no_same_sector_overwrites = config["journal_no_same_sector_overwrites"] == "true" ||
         config["journal_no_same_sector_overwrites"] == "1" || config["journal_no_same_sector_overwrites"] == "yes";
-    journal.inmemory = config["inmemory_journal"] != "false";
+    journal.inmemory = config["inmemory_journal"] != "false" && config["inmemory_journal"] != "0" &&
+        config["inmemory_journal"] != "no";
     // Validate
     if (journal.sector_count < 2)
     {
@@ -133,19 +135,24 @@ void blockstore_impl_t::calc_lengths()
     {
         metadata_buffer = memalign(MEM_ALIGNMENT, dsk.meta_len);
         if (!metadata_buffer)
-            throw std::runtime_error("Failed to allocate memory for the metadata");
+            throw std::runtime_error("Failed to allocate memory for the metadata ("+std::to_string(dsk.meta_len/1024/1024)+" MB)");
     }
-    else if (dsk.clean_entry_bitmap_size)
+    else if (dsk.clean_entry_bitmap_size || dsk.data_csum_type)
     {
-        clean_bitmap = (uint8_t*)malloc(dsk.block_count * 2*dsk.clean_entry_bitmap_size);
-        if (!clean_bitmap)
-            throw std::runtime_error("Failed to allocate memory for the metadata sparse write bitmap");
+        clean_bitmaps = (uint8_t*)malloc(dsk.block_count * 2 * dsk.clean_entry_bitmap_size);
+        if (!clean_bitmaps)
+        {
+            throw std::runtime_error(
+                "Failed to allocate memory for the metadata sparse write bitmap ("+
+                std::to_string(dsk.block_count * 2 * dsk.clean_entry_bitmap_size / 1024 / 1024)+" MB)"
+            );
+        }
     }
     if (journal.inmemory)
     {
         journal.buffer = memalign(MEM_ALIGNMENT, journal.len);
         if (!journal.buffer)
-            throw std::runtime_error("Failed to allocate memory for journal");
+            throw std::runtime_error("Failed to allocate memory for journal ("+std::to_string(journal.len/1024/1024)+" MB)");
     }
     else
     {

src/blockstore_read.cpp

@@ -1,6 +1,7 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)
 
+#include <limits.h>
 #include "blockstore_impl.h"
 
 int blockstore_impl_t::fulfill_read_push(blockstore_op_t *op, void *buf, uint64_t offset, uint64_t len,
@@ -8,12 +9,7 @@ int blockstore_impl_t::fulfill_read_push(blockstore_op_t *op, void *buf, uint64_
 {
     if (!len)
     {
-        // Zero-length version - skip
-        return 1;
-    }
-    else if (IS_IN_FLIGHT(item_state))
-    {
-        // Write not finished yet - skip
+        // Zero-length read
         return 1;
     }
     else if (IS_DELETE(item_state))
@@ -22,6 +18,7 @@ int blockstore_impl_t::fulfill_read_push(blockstore_op_t *op, void *buf, uint64_
         memset(buf, 0, len);
         return 1;
     }
+    assert(!IS_IN_FLIGHT(item_state));
     if (journal.inmemory && IS_JOURNAL(item_state))
     {
         memcpy(buf, (uint8_t*)journal.buffer + offset, len);
@@ -40,59 +37,115 @@ int blockstore_impl_t::fulfill_read_push(blockstore_op_t *op, void *buf, uint64_
     return 1;
 }
 
-// FIXME I've seen a bug here so I want some tests
-int blockstore_impl_t::fulfill_read(blockstore_op_t *read_op, uint64_t &fulfilled, uint32_t item_start, uint32_t item_end,
-    uint32_t item_state, uint64_t item_version, uint64_t item_location, uint64_t journal_sector)
+void blockstore_impl_t::find_holes(std::vector<copy_buffer_t> & read_vec,
+    uint32_t item_start, uint32_t item_end,
+    std::function<int(int, bool, uint32_t, uint32_t)> callback)
 {
-    uint32_t cur_start = item_start;
-    if (cur_start < read_op->offset + read_op->len && item_end > read_op->offset)
+    auto cur_start = item_start;
+    int i = 0;
+    while (cur_start < item_end)
     {
-        cur_start = cur_start < read_op->offset ? read_op->offset : cur_start;
-        item_end = item_end > read_op->offset + read_op->len ? read_op->offset + read_op->len : item_end;
-        auto it = PRIV(read_op)->read_vec.begin();
-        while (1)
+        // COPY_BUF_CSUM_FILL items are fake items inserted in the end, their offsets aren't in order
+        if (i >= read_vec.size() || read_vec[i].copy_flags & COPY_BUF_CSUM_FILL || read_vec[i].offset >= item_end)
         {
-            for (; it != PRIV(read_op)->read_vec.end(); it++)
-            {
-                if (it->offset >= cur_start)
-                {
-                    break;
-                }
-                else if (it->offset + it->len > cur_start)
-                {
-                    cur_start = it->offset + it->len;
-                    if (cur_start >= item_end)
-                    {
-                        goto endwhile;
-                    }
-                }
-            }
-            if (it == PRIV(read_op)->read_vec.end() || it->offset > cur_start)
-            {
-                fulfill_read_t el = {
-                    .offset = cur_start,
-                    .len = it == PRIV(read_op)->read_vec.end() || it->offset >= item_end ? item_end-cur_start : it->offset-cur_start,
-                    .journal_sector = journal_sector,
-                };
-                it = PRIV(read_op)->read_vec.insert(it, el);
-                if (!fulfill_read_push(read_op,
-                    (uint8_t*)read_op->buf + el.offset - read_op->offset,
-                    item_location + el.offset - item_start,
-                    el.len, item_state, item_version))
-                {
-                    return 0;
-                }
-                fulfilled += el.len;
-            }
-            cur_start = it->offset + it->len;
-            if (it == PRIV(read_op)->read_vec.end() || cur_start >= item_end)
-            {
-                break;
-            }
+            // Hole (at end): cur_start .. item_end
+            i += callback(i, false, cur_start, item_end);
+            break;
         }
+        else if (read_vec[i].offset > cur_start)
+        {
+            // Hole: cur_start .. min(read_vec[i].offset, item_end)
+            auto cur_end = read_vec[i].offset > item_end ? item_end : read_vec[i].offset;
+            i += callback(i, false, cur_start, cur_end);
+            cur_start = cur_end;
+        }
+        else if (read_vec[i].offset + read_vec[i].len > cur_start)
+        {
+            // Allocated: cur_start .. min(read_vec[i].offset + read_vec[i].len, item_end)
+            auto cur_end = read_vec[i].offset + read_vec[i].len;
+            cur_end = cur_end > item_end ? item_end : cur_end;
+            i += callback(i, true, cur_start, cur_end);
+            cur_start = cur_end;
+            i++;
+        }
+        else
+            i++;
     }
-endwhile:
-    return 1;
+}
+
+int blockstore_impl_t::fulfill_read(blockstore_op_t *read_op,
+    uint64_t &fulfilled, uint32_t item_start, uint32_t item_end, // FIXME: Rename item_* to dirty_*
+    uint32_t item_state, uint64_t item_version, uint64_t item_location,
+    uint64_t journal_sector, uint8_t *csum, int *dyn_data)
+{
+    int r = 1;
+    if (item_start < read_op->offset + read_op->len && item_end > read_op->offset)
+    {
+        auto & rv = PRIV(read_op)->read_vec;
+        auto rd_start = item_start < read_op->offset ? read_op->offset : item_start;
+        auto rd_end = item_end > read_op->offset + read_op->len ? read_op->offset + read_op->len : item_end;
+        find_holes(rv, rd_start, rd_end, [&](int pos, bool alloc, uint32_t start, uint32_t end)
+        {
+            if (!r || alloc)
+                return 0;
+            if (!journal.inmemory && dsk.csum_block_size > dsk.bitmap_granularity && IS_JOURNAL(item_state) && !IS_DELETE(item_state))
+            {
+                uint32_t blk_begin = (start/dsk.csum_block_size) * dsk.csum_block_size;
+                blk_begin = blk_begin < item_start ? item_start : blk_begin;
+                uint32_t blk_end = ((end-1) / dsk.csum_block_size + 1) * dsk.csum_block_size;
+                blk_end = blk_end > item_end ? item_end : blk_end;
+                rv.push_back((copy_buffer_t){
+                    .copy_flags = COPY_BUF_JOURNAL|COPY_BUF_CSUM_FILL,
+                    .offset = blk_begin,
+                    .len = blk_end-blk_begin,
+                    .csum_buf = (csum + (blk_begin/dsk.csum_block_size -
+                        item_start/dsk.csum_block_size) * (dsk.data_csum_type & 0xFF)),
+                    .dyn_data = dyn_data,
+                });
+                if (dyn_data)
+                {
+                    (*dyn_data)++;
+                }
+                // Submit the journal checksum block read
+                if (!read_checksum_block(read_op, 1, fulfilled, item_location - item_start))
+                {
+                    r = 0;
+                }
+                return 0;
+            }
+            copy_buffer_t el = {
+                .copy_flags = (IS_JOURNAL(item_state) ? COPY_BUF_JOURNAL : COPY_BUF_DATA),
+                .offset = start,
+                .len = end-start,
+                .disk_offset = item_location + start - item_start,
+                .journal_sector = (IS_JOURNAL(item_state) ? journal_sector : 0),
+                .csum_buf = !csum ? NULL : (csum + (start - item_start) / dsk.csum_block_size * (dsk.data_csum_type & 0xFF)),
+                .dyn_data = dyn_data,
+            };
+            if (dyn_data)
+            {
+                (*dyn_data)++;
+            }
+            if (IS_BIG_WRITE(item_state))
+            {
+                // If we don't track it then we may IN THEORY read another object's data:
+                // submit read -> remove the object -> flush remove -> overwrite with another object -> finish read
+                // Very improbable, but possible
+                PRIV(read_op)->clean_block_used = 1;
+            }
+            rv.insert(rv.begin() + pos, el);
+            fulfilled += el.len;
+            if (!fulfill_read_push(read_op,
+                (uint8_t*)read_op->buf + el.offset - read_op->offset,
+                item_location + el.offset - item_start,
+                el.len, item_state, item_version))
+            {
+                r = 0;
+            }
+            return 1;
+        });
+    }
+    return r;
 }
 
 uint8_t* blockstore_impl_t::get_clean_entry_bitmap(uint64_t block_loc, int offset)
@@ -106,10 +159,225 @@ uint8_t* blockstore_impl_t::get_clean_entry_bitmap(uint64_t block_loc, int offse
         clean_entry_bitmap = ((uint8_t*)metadata_buffer + sector + pos*dsk.clean_entry_size + sizeof(clean_disk_entry) + offset);
     }
     else
-        clean_entry_bitmap = (uint8_t*)(clean_bitmap + meta_loc*2*dsk.clean_entry_bitmap_size + offset);
+        clean_entry_bitmap = (uint8_t*)(clean_bitmaps + meta_loc*2*dsk.clean_entry_bitmap_size + offset);
     return clean_entry_bitmap;
 }
 
+int blockstore_impl_t::fill_partial_checksum_blocks(std::vector<copy_buffer_t> & rv, uint64_t & fulfilled,
+    uint8_t *clean_entry_bitmap, int *dyn_data, bool from_journal, uint8_t *read_buf, uint64_t read_offset, uint64_t read_end)
+{
+    if (read_end == read_offset)
+        return 0;
+    int required = 0;
+    read_buf -= read_offset;
+    uint32_t last_block = (read_end-1)/dsk.csum_block_size;
+    uint32_t start_block = read_offset/dsk.csum_block_size;
+    uint32_t end_block = 0;
+    while (start_block <= last_block)
+    {
+        if (read_range_fulfilled(rv, fulfilled, read_buf, clean_entry_bitmap,
+            start_block*dsk.csum_block_size < read_offset ? read_offset : start_block*dsk.csum_block_size,
+            (start_block+1)*dsk.csum_block_size > read_end ? read_end : (start_block+1)*dsk.csum_block_size))
+        {
+            // read_range_fulfilled() also adds zero-filled areas
+            start_block++;
+        }
+        else
+        {
+            // Find a sequence of checksum blocks required to be read
+            end_block = start_block;
+            while ((end_block+1)*dsk.csum_block_size < read_end &&
+                !read_range_fulfilled(rv, fulfilled, read_buf, clean_entry_bitmap,
+                    (end_block+1)*dsk.csum_block_size < read_offset ? read_offset : (end_block+1)*dsk.csum_block_size,
+                    (end_block+2)*dsk.csum_block_size > read_end ? read_end : (end_block+2)*dsk.csum_block_size))
+            {
+                end_block++;
+            }
+            end_block++;
+            // OK, mark this range as required
+            rv.push_back((copy_buffer_t){
+                .copy_flags = COPY_BUF_CSUM_FILL | (from_journal ? COPY_BUF_JOURNALED_BIG : 0),
+                .offset = start_block*dsk.csum_block_size,
+                .len = (end_block-start_block)*dsk.csum_block_size,
+                // save clean_entry_bitmap if we're reading clean data from the journal
+                .csum_buf = from_journal ? clean_entry_bitmap : NULL,
+                .dyn_data = dyn_data,
+            });
+            if (dyn_data)
+            {
+                (*dyn_data)++;
+            }
+            start_block = end_block;
+            required++;
+        }
+    }
+    return required;
+}
+
+// read_buf should be == op->buf - op->offset
+bool blockstore_impl_t::read_range_fulfilled(std::vector<copy_buffer_t> & rv, uint64_t & fulfilled, uint8_t *read_buf,
+    uint8_t *clean_entry_bitmap, uint32_t item_start, uint32_t item_end)
+{
+    bool all_done = true;
+    find_holes(rv, item_start, item_end, [&](int pos, bool alloc, uint32_t cur_start, uint32_t cur_end)
+    {
+        if (alloc)
+            return 0;
+        int diff = 0;
+        uint32_t bmp_start = cur_start/dsk.bitmap_granularity;
+        uint32_t bmp_end = cur_end/dsk.bitmap_granularity;
+        uint32_t bmp_pos = bmp_start;
+        while (bmp_pos < bmp_end)
+        {
+            while (bmp_pos < bmp_end && !(clean_entry_bitmap[bmp_pos >> 3] & (1 << (bmp_pos & 0x7))))
+                bmp_pos++;
+            if (bmp_pos > bmp_start)
+            {
+                // zero fill
+                copy_buffer_t el = {
+                    .copy_flags = COPY_BUF_ZERO,
+                    .offset = bmp_start*dsk.bitmap_granularity,
+                    .len = (bmp_pos-bmp_start)*dsk.bitmap_granularity,
+                };
+                rv.insert(rv.begin() + pos, el);
+                if (read_buf)
+                    memset(read_buf + el.offset, 0, el.len);
+                fulfilled += el.len;
+                diff++;
+            }
+            bmp_start = bmp_pos;
+            while (bmp_pos < bmp_end && (clean_entry_bitmap[bmp_pos >> 3] & (1 << (bmp_pos & 0x7))))
+                bmp_pos++;
+            if (bmp_pos > bmp_start)
+            {
+                // something is to be read
+                all_done = false;
+            }
+            bmp_start = bmp_pos;
+        }
+        return diff;
+    });
+    return all_done;
+}
+
+bool blockstore_impl_t::read_checksum_block(blockstore_op_t *op, int rv_pos, uint64_t &fulfilled, uint64_t clean_loc)
+{
+    auto & rv = PRIV(op)->read_vec;
+    auto *vi = &rv[rv.size()-rv_pos];
+    uint32_t item_start = vi->offset, item_end = vi->offset+vi->len;
+    uint32_t fill_size = 0;
+    int n_iov = 0;
+    find_holes(rv, item_start, item_end, [&](int pos, bool alloc, uint32_t cur_start, uint32_t cur_end)
+    {
+        if (alloc)
+        {
+            fill_size += cur_end-cur_start;
+            n_iov++;
+        }
+        else
+        {
+            if (cur_start < op->offset)
+            {
+                fill_size += op->offset-cur_start;
+                n_iov++;
+                cur_start = op->offset;
+            }
+            if (cur_end > op->offset+op->len)
+            {
+                fill_size += cur_end-(op->offset+op->len);
+                n_iov++;
+                cur_end = op->offset+op->len;
+            }
+            if (cur_end > cur_start)
+            {
+                n_iov++;
+            }
+        }
+        return 0;
+    });
+    void *buf = memalign_or_die(MEM_ALIGNMENT, fill_size + n_iov*sizeof(struct iovec));
+    iovec *iov = (struct iovec*)((uint8_t*)buf+fill_size);
+    n_iov = 0;
+    fill_size = 0;
+    find_holes(rv, item_start, item_end, [&](int pos, bool alloc, uint32_t cur_start, uint32_t cur_end)
+    {
+        int res = 0;
+        if (alloc)
+        {
+            iov[n_iov++] = (struct iovec){ (uint8_t*)buf+fill_size, cur_end-cur_start };
+            fill_size += cur_end-cur_start;
+        }
+        else
+        {
+            if (cur_start < op->offset)
+            {
+                iov[n_iov++] = (struct iovec){ (uint8_t*)buf+fill_size, op->offset-cur_start };
+                fill_size += op->offset-cur_start;
+                cur_start = op->offset;
+            }
+            auto lim_end = cur_end > op->offset+op->len ? op->offset+op->len : cur_end;
+            if (lim_end > cur_start)
+            {
+                iov[n_iov++] = (struct iovec){ (uint8_t*)op->buf+cur_start-op->offset, lim_end-cur_start };
+                rv.insert(rv.begin() + pos, (copy_buffer_t){
+                    .copy_flags = COPY_BUF_DATA,
+                    .offset = cur_start,
+                    .len = lim_end-cur_start,
+                });
+                fulfilled += lim_end-cur_start;
+                res++;
+            }
+            if (cur_end > op->offset+op->len)
+            {
+                iov[n_iov++] = (struct iovec){ (uint8_t*)buf+fill_size, cur_end - (op->offset+op->len) };
+                fill_size += cur_end - (op->offset+op->len);
+                cur_end = op->offset+op->len;
+            }
+        }
+        return res;
+    });
+    vi = &rv[rv.size()-rv_pos];
+    // Save buf into read_vec too but in a creepy way
+    // FIXME: Shit, something else should be invented %)
+    *vi = (copy_buffer_t){
+        .copy_flags = vi->copy_flags,
+        .offset = vi->offset,
+        .len = ((uint64_t)n_iov << 32) | fill_size,
+        .disk_offset = clean_loc + item_start,
+        .buf = (uint8_t*)buf,
+        .csum_buf = vi->csum_buf,
+        .dyn_data = vi->dyn_data,
+    };
+    int submit_fd = (vi->copy_flags & COPY_BUF_JOURNAL ? dsk.journal_fd : dsk.data_fd);
+    uint64_t submit_offset = (vi->copy_flags & COPY_BUF_JOURNAL ? journal.offset : dsk.data_offset);
+    uint32_t d_pos = 0;
+    for (int n_pos = 0; n_pos < n_iov; n_pos += IOV_MAX)
+    {
+        int n_cur = n_iov-n_pos < IOV_MAX ? n_iov-n_pos : IOV_MAX;
+        BS_SUBMIT_GET_SQE(sqe, data);
+        PRIV(op)->pending_ops++;
+        my_uring_prep_readv(sqe, submit_fd, iov + n_pos, n_cur, submit_offset + clean_loc + item_start + d_pos);
+        data->callback = [this, op](ring_data_t *data) { handle_read_event(data, op); };
+        if (n_pos > 0 || n_pos + IOV_MAX < n_iov)
+        {
+            uint32_t d_len = 0;
+            for (int i = 0; i < IOV_MAX; i++)
+                d_len += iov[n_pos+i].iov_len;
+            data->iov.iov_len = d_len;
+            d_pos += d_len;
+        }
+        else
+            data->iov.iov_len = item_end-item_start;
+    }
+    if (!(vi->copy_flags & COPY_BUF_JOURNAL))
+    {
+        // Reads running parallel to flushes of the same clean block may read
+        // a mixture of old and new data. So we don't verify checksums for such blocks.
+        PRIV(op)->clean_block_used = 1;
+    }
+    return true;
+}
+
 int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
 {
     auto & clean_db = clean_db_shard(read_op->oid);
@@ -131,6 +399,8 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
     }
     uint64_t fulfilled = 0;
     PRIV(read_op)->pending_ops = 0;
+    PRIV(read_op)->clean_block_used = 0;
+    auto & rv = PRIV(read_op)->read_vec;
     uint64_t result_version = 0;
     if (dirty_found)
     {
@@ -148,23 +418,36 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
                     FINISH_OP(read_op);
                     return 2;
                 }
+                int *dyn_data = (int*)(dsk.csum_block_size > 0 && alloc_dyn_data ? dirty.dyn_data : NULL);
+                uint8_t *bmp_ptr = (alloc_dyn_data
+                    ? (uint8_t*)dirty.dyn_data + sizeof(int) : (uint8_t*)&dirty.dyn_data);
                 if (!result_version)
                 {
                     result_version = dirty_it->first.version;
                     if (read_op->bitmap)
                     {
-                        void *bmp_ptr = (dsk.clean_entry_bitmap_size > sizeof(void*) ? dirty_it->second.bitmap : &dirty_it->second.bitmap);
                         memcpy(read_op->bitmap, bmp_ptr, dsk.clean_entry_bitmap_size);
                     }
                 }
                 // If inmemory_journal is false, journal trim will have to wait until the read is completed
-                if (!fulfill_read(read_op, fulfilled, dirty.offset, dirty.offset + dirty.len,
-                    dirty.state, dirty_it->first.version, dirty.location + (IS_JOURNAL(dirty.state) ? 0 : dirty.offset),
-                    (IS_JOURNAL(dirty.state) ? dirty.journal_sector+1 : 0)))
+                if (!IS_JOURNAL(dirty.state))
                 {
-                    // need to wait. undo added requests, don't dequeue op
-                    PRIV(read_op)->read_vec.clear();
-                    return 0;
+                    // Read from data disk, possibly checking checksums
+                    if (!fulfill_clean_read(read_op, fulfilled, bmp_ptr, dyn_data,
+                        dirty.offset, dirty.offset+dirty.len, dirty.location, dirty_it->first.version))
+                    {
+                        goto undo_read;
+                    }
+                }
+                else
+                {
+                    // Copy from memory or read from journal, possibly checking checksums
+                    if (!fulfill_read(read_op, fulfilled, dirty.offset, dirty.offset + dirty.len,
+                        dirty.state, dirty_it->first.version, dirty.location, dirty.journal_sector+1,
+                        journal.inmemory ? NULL : bmp_ptr+dsk.clean_entry_bitmap_size, dyn_data))
+                    {
+                        goto undo_read;
+                    }
                 }
             }
             if (fulfilled == read_op->len || dirty_it == dirty_db.begin())
@@ -187,50 +470,10 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
         }
         if (fulfilled < read_op->len)
         {
-            if (!dsk.clean_entry_bitmap_size)
+            if (!fulfill_clean_read(read_op, fulfilled, NULL, NULL, 0, dsk.data_block_size,
+                clean_it->second.location, clean_it->second.version))
             {
-                if (!fulfill_read(read_op, fulfilled, 0, dsk.data_block_size,
-                    (BS_ST_BIG_WRITE | BS_ST_STABLE), 0, clean_it->second.location, 0))
-                {
-                    // need to wait. undo added requests, don't dequeue op
-                    PRIV(read_op)->read_vec.clear();
-                    return 0;
-                }
-            }
-            else
-            {
-                uint8_t *clean_entry_bitmap = get_clean_entry_bitmap(clean_it->second.location, 0);
-                uint64_t bmp_start = 0, bmp_end = 0, bmp_size = dsk.data_block_size/dsk.bitmap_granularity;
-                while (bmp_start < bmp_size)
-                {
-                    while (!(clean_entry_bitmap[bmp_end >> 3] & (1 << (bmp_end & 0x7))) && bmp_end < bmp_size)
-                    {
-                        bmp_end++;
-                    }
-                    if (bmp_end > bmp_start)
-                    {
-                        // fill with zeroes
-                        assert(fulfill_read(read_op, fulfilled, bmp_start * dsk.bitmap_granularity,
-                            bmp_end * dsk.bitmap_granularity, (BS_ST_DELETE | BS_ST_STABLE), 0, 0, 0));
-                    }
-                    bmp_start = bmp_end;
-                    while (clean_entry_bitmap[bmp_end >> 3] & (1 << (bmp_end & 0x7)) && bmp_end < bmp_size)
-                    {
-                        bmp_end++;
-                    }
-                    if (bmp_end > bmp_start)
-                    {
-                        if (!fulfill_read(read_op, fulfilled, bmp_start * dsk.bitmap_granularity,
-                            bmp_end * dsk.bitmap_granularity, (BS_ST_BIG_WRITE | BS_ST_STABLE), 0,
-                            clean_it->second.location + bmp_start * dsk.bitmap_granularity, 0))
-                        {
-                            // need to wait. undo added requests, don't dequeue op
-                            PRIV(read_op)->read_vec.clear();
-                            return 0;
-                        }
-                        bmp_start = bmp_end;
-                    }
-                }
+                goto undo_read;
             }
         }
     }
@@ -242,11 +485,7 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
         FINISH_OP(read_op);
         return 2;
     }
-    if (fulfilled < read_op->len)
-    {
-        assert(fulfill_read(read_op, fulfilled, 0, dsk.data_block_size, (BS_ST_DELETE | BS_ST_STABLE), 0, 0, 0));
-        assert(fulfilled == read_op->len);
-    }
+    assert(fulfilled == read_op->len);
     read_op->version = result_version;
     if (!PRIV(read_op)->pending_ops)
     {
@@ -271,6 +510,309 @@ int blockstore_impl_t::dequeue_read(blockstore_op_t *read_op)
     }
     read_op->retval = 0;
     return 2;
+undo_read:
+    // need to wait. undo added requests, don't dequeue op
+    if (dsk.csum_block_size > dsk.bitmap_granularity)
+    {
+        for (auto & vec: rv)
+        {
+            if ((vec.copy_flags & COPY_BUF_CSUM_FILL) && vec.buf)
+            {
+                free(vec.buf);
+                vec.buf = NULL;
+            }
+            if (vec.dyn_data && --(*vec.dyn_data) == 0) // refcount
+            {
+                free(vec.dyn_data);
+                vec.dyn_data = NULL;
+            }
+        }
+    }
+    rv.clear();
+    return 0;
+}
+
+int blockstore_impl_t::pad_journal_read(std::vector<copy_buffer_t> & rv, copy_buffer_t & cp,
+    // FIXME Passing dirty_entry& would be nicer
+    uint64_t dirty_offset, uint64_t dirty_end, uint64_t dirty_loc, uint8_t *csum_ptr, int *dyn_data,
+    uint64_t offset, uint64_t submit_len, uint64_t & blk_begin, uint64_t & blk_end, uint8_t* & blk_buf)
+{
+    if (offset % dsk.csum_block_size || submit_len % dsk.csum_block_size)
+    {
+        if (offset < blk_end)
+        {
+            // Already being read as a part of the previous checksum block series
+            cp.buf = blk_buf + offset - blk_begin;
+            cp.copy_flags |= COPY_BUF_COALESCED;
+            if (offset+submit_len > blk_end)
+                cp.len = blk_end-offset;
+            return 2;
+        }
+        else
+        {
+            // We don't use fill_partial_checksum_blocks for journal because journal writes never have holes (internal bitmap)
+            blk_begin = (offset/dsk.csum_block_size) * dsk.csum_block_size;
+            blk_begin = blk_begin < dirty_offset ? dirty_offset : blk_begin;
+            blk_end = ((offset+submit_len-1)/dsk.csum_block_size + 1) * dsk.csum_block_size;
+            blk_end = blk_end > dirty_end ? dirty_end : blk_end;
+            if (blk_begin < offset || blk_end > offset+submit_len)
+            {
+                blk_buf = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, blk_end-blk_begin);
+                cp.buf = blk_buf + offset - blk_begin;
+                cp.copy_flags |= COPY_BUF_COALESCED;
+                rv.push_back((copy_buffer_t){
+                    .copy_flags = COPY_BUF_JOURNAL|COPY_BUF_CSUM_FILL,
+                    .offset = blk_begin,
+                    .len = blk_end-blk_begin,
+                    .disk_offset = dirty_loc + blk_begin - dirty_offset,
+                    .buf = blk_buf,
+                    .csum_buf = (csum_ptr + (blk_begin/dsk.csum_block_size -
+                        dirty_offset/dsk.csum_block_size) * (dsk.data_csum_type & 0xFF)),
+                    .dyn_data = dyn_data,
+                });
+                if (dyn_data)
+                {
+                    (*dyn_data)++;
+                }
+                return 1;
+            }
+        }
+    }
+    return 0;
+}
+
+bool blockstore_impl_t::fulfill_clean_read(blockstore_op_t *read_op, uint64_t & fulfilled,
+    uint8_t *clean_entry_bitmap, int *dyn_data, uint32_t item_start, uint32_t item_end, uint64_t clean_loc, uint64_t clean_ver)
+{
+    bool from_journal = clean_entry_bitmap != NULL;
+    if (!clean_entry_bitmap)
+    {
+        // NULL clean_entry_bitmap means we're reading from data, not from the journal,
+        // and the bitmap location is obvious
+        clean_entry_bitmap = get_clean_entry_bitmap(clean_loc, 0);
+    }
+    if (dsk.csum_block_size > dsk.bitmap_granularity)
+    {
+        auto & rv = PRIV(read_op)->read_vec;
+        int req = fill_partial_checksum_blocks(rv, fulfilled, clean_entry_bitmap, dyn_data, from_journal,
+            (uint8_t*)read_op->buf, read_op->offset, read_op->offset+read_op->len);
+        if (!inmemory_meta && !from_journal && req > 0)
+        {
+            // Read checksums from disk
+            uint8_t *csum_buf = read_clean_meta_block(read_op, clean_loc, rv.size()-req);
+            for (int i = req; i > 0; i--)
+            {
+                rv[rv.size()-i].csum_buf = csum_buf;
+            }
+        }
+        for (int i = req; i > 0; i--)
+        {
+            if (!read_checksum_block(read_op, i, fulfilled, clean_loc))
+            {
+                return false;
+            }
+        }
+        PRIV(read_op)->clean_block_used = req > 0;
+    }
+    else if (from_journal)
+    {
+        // Don't scan bitmap - journal writes don't have holes (internal bitmap)!
+        uint8_t *csum = !dsk.csum_block_size ? 0 : (clean_entry_bitmap + dsk.clean_entry_bitmap_size +
+            item_start/dsk.csum_block_size*(dsk.data_csum_type & 0xFF));
+        if (!fulfill_read(read_op, fulfilled, item_start, item_end,
+            (BS_ST_BIG_WRITE | BS_ST_STABLE), 0, clean_loc + item_start, 0, csum, dyn_data))
+        {
+            return false;
+        }
+        if (item_start > 0 && fulfilled < read_op->len)
+        {
+            // fill with zeroes
+            assert(fulfill_read(read_op, fulfilled, 0, item_start, (BS_ST_DELETE | BS_ST_STABLE), 0, 0, 0, NULL, NULL));
+        }
+        if (item_end < dsk.data_block_size && fulfilled < read_op->len)
+        {
+            // fill with zeroes
+            assert(fulfill_read(read_op, fulfilled, item_end, dsk.data_block_size, (BS_ST_DELETE | BS_ST_STABLE), 0, 0, 0, NULL, NULL));
+        }
+    }
+    else
+    {
+        bool csum_done = !dsk.csum_block_size || inmemory_meta;
+        uint8_t *csum_buf = clean_entry_bitmap;
+        uint64_t bmp_start = 0, bmp_end = 0, bmp_size = dsk.data_block_size/dsk.bitmap_granularity;
+        while (bmp_start < bmp_size)
+        {
+            while (!(clean_entry_bitmap[bmp_end >> 3] & (1 << (bmp_end & 0x7))) && bmp_end < bmp_size)
+            {
+                bmp_end++;
+            }
+            if (bmp_end > bmp_start)
+            {
+                // fill with zeroes
+                assert(fulfill_read(read_op, fulfilled, bmp_start * dsk.bitmap_granularity,
+                    bmp_end * dsk.bitmap_granularity, (BS_ST_DELETE | BS_ST_STABLE), 0, 0, 0, NULL, NULL));
+            }
+            bmp_start = bmp_end;
+            while (clean_entry_bitmap[bmp_end >> 3] & (1 << (bmp_end & 0x7)) && bmp_end < bmp_size)
+            {
+                bmp_end++;
+            }
+            if (bmp_end > bmp_start)
+            {
+                if (!csum_done)
+                {
+                    // Read checksums from disk
+                    csum_buf = read_clean_meta_block(read_op, clean_loc, PRIV(read_op)->read_vec.size());
+                    csum_done = true;
+                }
+                uint8_t *csum = !dsk.csum_block_size ? 0 : (csum_buf + 2*dsk.clean_entry_bitmap_size + bmp_start*(dsk.data_csum_type & 0xFF));
+                if (!fulfill_read(read_op, fulfilled, bmp_start * dsk.bitmap_granularity,
+                    bmp_end * dsk.bitmap_granularity, (BS_ST_BIG_WRITE | BS_ST_STABLE), 0,
+                    clean_loc + bmp_start * dsk.bitmap_granularity, 0, csum, dyn_data))
+                {
+                    return false;
+                }
+                bmp_start = bmp_end;
+            }
+        }
+    }
+    // Increment reference counter if clean data is being read from the disk
+    if (PRIV(read_op)->clean_block_used)
+    {
+        auto & uo = used_clean_objects[clean_loc];
+        uo.refs++;
+        if (dsk.csum_block_size && flusher->is_mutated(clean_loc))
+            uo.was_changed = true;
+        PRIV(read_op)->clean_block_used = clean_loc;
+    }
+    return true;
+}
+
+uint8_t* blockstore_impl_t::read_clean_meta_block(blockstore_op_t *op, uint64_t clean_loc, int rv_pos)
+{
+    auto & rv = PRIV(op)->read_vec;
+    auto sector = ((clean_loc >> dsk.block_order) / (dsk.meta_block_size / dsk.clean_entry_size)) * dsk.meta_block_size;
+    auto pos = ((clean_loc >> dsk.block_order) % (dsk.meta_block_size / dsk.clean_entry_size)) * dsk.clean_entry_size;
+    uint8_t *buf = (uint8_t*)memalign_or_die(MEM_ALIGNMENT, dsk.meta_block_size);
+    rv.insert(rv.begin()+rv_pos, (copy_buffer_t){
+        .copy_flags = COPY_BUF_META_BLOCK|COPY_BUF_CSUM_FILL,
+        .offset = pos,
+        .buf = buf,
+    });
+    BS_SUBMIT_GET_SQE(sqe, data);
+    data->iov = (struct iovec){ buf, dsk.meta_block_size };
+    PRIV(op)->pending_ops++;
+    my_uring_prep_readv(sqe, dsk.meta_fd, &data->iov, 1, dsk.meta_offset + dsk.meta_block_size + sector);
+    data->callback = [this, op](ring_data_t *data) { handle_read_event(data, op); };
+    // return pointer to checksums + bitmap
+    return buf + pos + sizeof(clean_disk_entry);
+}
+
+bool blockstore_impl_t::verify_padded_checksums(uint8_t *clean_entry_bitmap, uint8_t *csum_buf, uint32_t offset,
+    iovec *iov, int n_iov, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb)
+{
+    assert(!(offset % dsk.csum_block_size));
+    uint32_t *csums = (uint32_t*)csum_buf;
+    uint32_t block_csum = 0;
+    uint32_t block_done = 0;
+    uint32_t block_num = clean_entry_bitmap ? offset/dsk.csum_block_size : 0;
+    uint32_t bmp_pos = offset/dsk.bitmap_granularity;
+    for (int i = 0; i < n_iov; i++)
+    {
+        uint32_t pos = 0;
+        while (pos < iov[i].iov_len)
+        {
+            uint32_t start = pos;
+            uint8_t bit = (clean_entry_bitmap[bmp_pos >> 3] >> (bmp_pos & 0x7)) & 1;
+            while (pos < iov[i].iov_len && ((clean_entry_bitmap[bmp_pos >> 3] >> (bmp_pos & 0x7)) & 1) == bit)
+            {
+                pos += dsk.bitmap_granularity;
+                bmp_pos++;
+            }
+            uint32_t len = pos-start;
+            auto buf = (uint8_t*)iov[i].iov_base+start;
+            while (block_done+len >= dsk.csum_block_size)
+            {
+                auto cur_len = dsk.csum_block_size-block_done;
+                block_csum = crc32c_pad(block_csum, buf, bit ? cur_len : 0, bit ? 0 : cur_len, 0);
+                if (block_csum != csums[block_num])
+                {
+                    if (bad_block_cb)
+                        bad_block_cb(block_num*dsk.csum_block_size, block_csum, csums[block_num]);
+                    else
+                        return false;
+                }
+                block_num++;
+                buf += cur_len;
+                len -= cur_len;
+                block_done = block_csum = 0;
+            }
+            if (len > 0)
+            {
+                block_csum = crc32c_pad(block_csum, buf, bit ? len : 0, bit ? 0 : len, 0);
+                block_done += len;
+            }
+        }
+    }
+    assert(!block_done);
+    return true;
+}
+
+bool blockstore_impl_t::verify_journal_checksums(uint8_t *csums, uint32_t offset,
+    iovec *iov, int n_iov, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb)
+{
+    uint32_t block_csum = 0;
+    uint32_t block_num = 0;
+    uint32_t block_done = offset%dsk.csum_block_size;
+    for (int i = 0; i < n_iov; i++)
+    {
+        uint32_t len = iov[i].iov_len;
+        auto buf = (uint8_t*)iov[i].iov_base;
+        while (block_done+len >= dsk.csum_block_size)
+        {
+            auto cur_len = dsk.csum_block_size-block_done;
+            block_csum = crc32c(block_csum, buf, cur_len);
+            if (block_csum != ((uint32_t*)csums)[block_num])
+            {
+                if (bad_block_cb)
+                    bad_block_cb(block_num*dsk.csum_block_size, block_csum, ((uint32_t*)csums)[block_num]);
+                else
+                    return false;
+            }
+            block_num++;
+            buf += cur_len;
+            len -= cur_len;
+            block_done = block_csum = 0;
+        }
+        if (len > 0)
+        {
+            block_csum = crc32c(block_csum, buf, len);
+            block_done += len;
+        }
+    }
+    if (block_done > 0 && block_csum != ((uint32_t*)csums)[block_num])
+    {
+        if (bad_block_cb)
+            bad_block_cb(block_num*dsk.csum_block_size, block_csum, ((uint32_t*)csums)[block_num]);
+        else
+            return false;
+    }
+    return true;
+}
+
+bool blockstore_impl_t::verify_clean_padded_checksums(blockstore_op_t *op, uint64_t clean_loc, uint8_t *dyn_data, bool from_journal,
+    iovec *iov, int n_iov, std::function<void(uint32_t, uint32_t, uint32_t)> bad_block_cb)
+{
+    uint32_t offset = clean_loc % dsk.data_block_size;
+    if (from_journal)
+        return verify_padded_checksums(dyn_data, dyn_data + dsk.clean_entry_bitmap_size, offset, iov, n_iov, bad_block_cb);
+    clean_loc = (clean_loc >> dsk.block_order) << dsk.block_order;
+    if (!dyn_data)
+    {
+        assert(inmemory_meta);
+        dyn_data = get_clean_entry_bitmap(clean_loc, 0);
+    }
+    return verify_padded_checksums(dyn_data, dyn_data + 2*dsk.clean_entry_bitmap_size, offset, iov, n_iov, bad_block_cb);
 }
 
 void blockstore_impl_t::handle_read_event(ring_data_t *data, blockstore_op_t *op)
@@ -284,6 +826,139 @@ void blockstore_impl_t::handle_read_event(ring_data_t *data, blockstore_op_t *op
     }
     if (PRIV(op)->pending_ops == 0)
     {
+        if (dsk.csum_block_size)
+        {
+            // verify checksums if required
+            auto & rv = PRIV(op)->read_vec;
+            void *meta_block = NULL;
+            if (dsk.csum_block_size > dsk.bitmap_granularity)
+            {
+                for (int i = rv.size()-1; i >= 0 && (rv[i].copy_flags & COPY_BUF_CSUM_FILL); i--)
+                {
+                    if (rv[i].copy_flags & COPY_BUF_META_BLOCK)
+                    {
+                        // Metadata read. Skip
+                        assert(!meta_block);
+                        meta_block = rv[i].buf;
+                        rv[i].buf = NULL;
+                        continue;
+                    }
+                    struct iovec *iov = (struct iovec*)((uint8_t*)rv[i].buf + (rv[i].len & 0xFFFFFFFF));
+                    int n_iov = rv[i].len >> 32;
+                    bool ok = true;
+                    if (rv[i].copy_flags & COPY_BUF_JOURNAL)
+                    {
+                        // SMALL_WRITE from journal
+                        verify_journal_checksums(
+                            rv[i].csum_buf, rv[i].offset, iov, n_iov,
+                            [&](uint32_t bad_block, uint32_t calc_csum, uint32_t stored_csum)
+                            {
+                                ok = false;
+                                printf(
+                                    "Checksum mismatch in object %lx:%lx v%lu in journal at 0x%lx, checksum block #%u: got %08x, expected %08x\n",
+                                    op->oid.inode, op->oid.stripe, op->version,
+                                    rv[i].disk_offset, bad_block / dsk.csum_block_size, calc_csum, stored_csum
+                                );
+                            }
+                        );
+                    }
+                    else
+                    {
+                        // BIG_WRITE from journal or clean data
+                        // Do not verify checksums if the data location is/was mutated by flushers
+                        auto & uo = used_clean_objects.at((rv[i].disk_offset >> dsk.block_order) << dsk.block_order);
+                        if (!uo.was_changed)
+                        {
+                            verify_clean_padded_checksums(
+                                op, rv[i].disk_offset, rv[i].csum_buf, (rv[i].copy_flags & COPY_BUF_JOURNALED_BIG), iov, n_iov,
+                                [&](uint32_t bad_block, uint32_t calc_csum, uint32_t stored_csum)
+                                {
+                                    ok = false;
+                                    printf(
+                                        "Checksum mismatch in object %lx:%lx v%lu in %s data at 0x%lx, checksum block #%u: got %08x, expected %08x\n",
+                                        op->oid.inode, op->oid.stripe, op->version,
+                                        (rv[i].copy_flags & COPY_BUF_JOURNALED_BIG ? "redirect-write" : "clean"),
+                                        rv[i].disk_offset, bad_block / dsk.csum_block_size, calc_csum, stored_csum
+                                    );
+                                }
+                            );
+                        }
+                    }
+                    if (!ok)
+                    {
+                        op->retval = -EDOM;
+                    }
+                    free(rv[i].buf);
+                    rv[i].buf = NULL;
+                    if (rv[i].dyn_data && --(*rv[i].dyn_data) == 0) // refcount
+                    {
+                        free(rv[i].dyn_data);
+                        rv[i].dyn_data = NULL;
+                    }
+                }
+            }
+            else
+            {
+                for (auto & vec: rv)
+                {
+                    if (vec.copy_flags & COPY_BUF_META_BLOCK)
+                    {
+                        // Metadata read. Skip
+                        assert(!meta_block);
+                        meta_block = vec.buf;
+                        vec.buf = NULL;
+                        continue;
+                    }
+                    if (vec.csum_buf)
+                    {
+                        uint32_t *csum = (uint32_t*)vec.csum_buf;
+                        for (size_t p = 0; p < vec.len; p += dsk.csum_block_size, csum++)
+                        {
+                            if (crc32c(0, (uint8_t*)op->buf + vec.offset - op->offset + p, dsk.csum_block_size) != *csum)
+                            {
+                                // checksum error
+                                printf(
+                                    "Checksum mismatch in object %lx:%lx v%lu in %s area at offset 0x%lx+0x%lx: %08x vs %08x\n",
+                                    op->oid.inode, op->oid.stripe, op->version,
+                                    (vec.copy_flags & COPY_BUF_JOURNAL) ? "journal" : "data", vec.disk_offset, p,
+                                    crc32c(0, (uint8_t*)op->buf + vec.offset - op->offset + p, dsk.csum_block_size), *csum
+                                );
+                                op->retval = -EDOM;
+                                break;
+                            }
+                        }
+                    }
+                    if (vec.dyn_data && --(*vec.dyn_data) == 0) // refcount
+                    {
+                        free(vec.dyn_data);
+                        vec.dyn_data = NULL;
+                    }
+                }
+            }
+            if (meta_block)
+            {
+                // Free after checking
+                free(meta_block);
+                meta_block = NULL;
+            }
+        }
+        if (PRIV(op)->clean_block_used)
+        {
+            // Release clean data block
+            auto uo_it = used_clean_objects.find(PRIV(op)->clean_block_used);
+            if (uo_it != used_clean_objects.end())
+            {
+                uo_it->second.refs--;
+                if (uo_it->second.refs <= 0)
+                {
+                    if (uo_it->second.was_freed)
+                    {
+                        data_alloc->set(PRIV(op)->clean_block_used, false);
+                    }
+                    used_clean_objects.erase(uo_it);
+                }
+            }
+        }
         if (!journal.inmemory)
         {
             // Release journal sector usage
@@ -324,8 +999,9 @@ int blockstore_impl_t::read_bitmap(object_id oid, uint64_t target_version, void
                     *result_version = dirty_it->first.version;
                 if (bitmap)
                 {
-                    void *bmp_ptr = (dsk.clean_entry_bitmap_size > sizeof(void*) ? dirty_it->second.bitmap : &dirty_it->second.bitmap);
-                    memcpy(bitmap, bmp_ptr, dsk.clean_entry_bitmap_size);
+                    void *dyn_ptr = (alloc_dyn_data
+                        ? (uint8_t*)dirty_it->second.dyn_data + sizeof(int) : (uint8_t*)&dirty_it->second.dyn_data);
+                    memcpy(bitmap, dyn_ptr, dsk.clean_entry_bitmap_size);
                 }
                 return 0;
             }

src/blockstore_rollback.cpp

@@ -218,7 +218,7 @@ void blockstore_impl_t::erase_dirty(blockstore_dirty_db_t::iterator dirty_start,
         auto used = --journal.used_sectors[dirty_it->second.journal_sector];
 #ifdef BLOCKSTORE_DEBUG
         printf(
-            "remove usage of journal offset %08lx by %lx:%lx v%lu (%d refs)\n", dirty_it->second.journal_sector,
+            "remove usage of journal offset %08lx by %lx:%lx v%lu (%lu refs)\n", dirty_it->second.journal_sector,
             dirty_it->first.oid.inode, dirty_it->first.oid.stripe, dirty_it->first.version, used
         );
 #endif
@@ -227,11 +227,7 @@ void blockstore_impl_t::erase_dirty(blockstore_dirty_db_t::iterator dirty_start,
             journal.used_sectors.erase(dirty_it->second.journal_sector);
             flusher->mark_trim_possible();
         }
-        if (dsk.clean_entry_bitmap_size > sizeof(void*))
-        {
-            free(dirty_it->second.bitmap);
-            dirty_it->second.bitmap = NULL;
-        }
+        free_dirty_dyn_data(dirty_it->second);
         if (dirty_it == dirty_start)
         {
             break;
@@ -240,3 +236,18 @@ void blockstore_impl_t::erase_dirty(blockstore_dirty_db_t::iterator dirty_start,
     }
     dirty_db.erase(dirty_start, dirty_end);
 }
+
+void blockstore_impl_t::free_dirty_dyn_data(dirty_entry & e)
+{
+    if (e.dyn_data)
+    {
+        if (alloc_dyn_data &&
+            --*((int*)e.dyn_data) == 0) // refcount
+        {
+            // dyn_data contains the bitmap and checksums
+            // free it if it doesn't refer to the in-memory journal
+            free(e.dyn_data);
+        }
+        e.dyn_data = NULL;
+    }
+}

src/blockstore_sync.cpp

@@ -27,8 +27,6 @@ int blockstore_impl_t::continue_sync(blockstore_op_t *op)
         unsynced_big_write_count -= unsynced_big_writes.size();
         PRIV(op)->sync_big_writes.swap(unsynced_big_writes);
         PRIV(op)->sync_small_writes.swap(unsynced_small_writes);
-        PRIV(op)->sync_small_checked = 0;
-        PRIV(op)->sync_big_checked = 0;
         unsynced_big_writes.clear();
         unsynced_small_writes.clear();
         if (PRIV(op)->sync_big_writes.size() > 0)
@@ -78,7 +76,23 @@ int blockstore_impl_t::continue_sync(blockstore_op_t *op)
         // 2nd step: Data device is synced, prepare & write journal entries
         // Check space in the journal and journal memory buffers
         blockstore_journal_check_t space_check(this);
-        if (!space_check.check_available(op, PRIV(op)->sync_big_writes.size(),
+        if (dsk.csum_block_size)
+        {
+            // More complex check because all journal entries have different lengths
+            int left = PRIV(op)->sync_big_writes.size();
+            for (auto & sbw: PRIV(op)->sync_big_writes)
+            {
+                left--;
+                auto & dirty_entry = dirty_db.at(sbw);
+                uint64_t dyn_size = dsk.dirty_dyn_size(dirty_entry.offset, dirty_entry.len);
+                if (!space_check.check_available(op, 1, sizeof(journal_entry_big_write) + dyn_size,
+                    left == 0 ? JOURNAL_STABILIZE_RESERVATION : 0))
+                {
+                    return 0;
+                }
+            }
+        }
+        else if (!space_check.check_available(op, PRIV(op)->sync_big_writes.size(),
             sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size, JOURNAL_STABILIZE_RESERVATION))
         {
             return 0;
@@ -90,16 +104,17 @@ int blockstore_impl_t::continue_sync(blockstore_op_t *op)
         int s = 0;
         while (it != PRIV(op)->sync_big_writes.end())
         {
-            if (!journal.entry_fits(sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size) &&
+            auto & dirty_entry = dirty_db.at(*it);
+            uint64_t dyn_size = dsk.dirty_dyn_size(dirty_entry.offset, dirty_entry.len);
+            if (!journal.entry_fits(sizeof(journal_entry_big_write) + dyn_size) &&
                 journal.sector_info[journal.cur_sector].dirty)
             {
                 prepare_journal_sector_write(journal.cur_sector, op);
                 s++;
             }
-            auto & dirty_entry = dirty_db.at(*it);
             journal_entry_big_write *je = (journal_entry_big_write*)prefill_single_journal_entry(
                 journal, (dirty_entry.state & BS_ST_INSTANT) ? JE_BIG_WRITE_INSTANT : JE_BIG_WRITE,
-                sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size
+                sizeof(journal_entry_big_write) + dyn_size
             );
             dirty_entry.journal_sector = journal.sector_info[journal.cur_sector].offset;
             journal.used_sectors[journal.sector_info[journal.cur_sector].offset]++;
@@ -115,8 +130,8 @@ int blockstore_impl_t::continue_sync(blockstore_op_t *op)
             je->offset = dirty_entry.offset;
             je->len = dirty_entry.len;
             je->location = dirty_entry.location;
-            memcpy((void*)(je+1), (dsk.clean_entry_bitmap_size > sizeof(void*)
-                ? dirty_entry.bitmap : &dirty_entry.bitmap), dsk.clean_entry_bitmap_size);
+            memcpy((void*)(je+1), (alloc_dyn_data
+                ? (uint8_t*)dirty_entry.dyn_data+sizeof(int) : (uint8_t*)&dirty_entry.dyn_data), dyn_size);
             je->crc32 = je_crc32((journal_entry*)je);
             journal.crc32_last = je->crc32;
             it++;

src/blockstore_write.cpp

@@ -8,12 +8,21 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
     // Check or assign version number
     bool found = false, deleted = false, unsynced = false, is_del = (op->opcode == BS_OP_DELETE);
     bool wait_big = false, wait_del = false;
-    void *bmp = NULL;
-    uint64_t version = 1;
-    if (!is_del && dsk.clean_entry_bitmap_size > sizeof(void*))
+    void *dyn = NULL;
+    if (is_del)
     {
-        bmp = calloc_or_die(1, dsk.clean_entry_bitmap_size);
+        op->len = 0;
     }
+    size_t dyn_size = dsk.dirty_dyn_size(op->offset, op->len);
+    if (!is_del && alloc_dyn_data)
+    {
+        // FIXME: Working with `dyn_data` has to be refactored somehow but I first have to decide how :)
+        // +sizeof(int) = refcount
+        dyn = calloc_or_die(1, dyn_size+sizeof(int));
+        *((int*)dyn) = 1;
+    }
+    uint8_t *dyn_ptr = (uint8_t*)(alloc_dyn_data ? dyn+sizeof(int) : &dyn);
+    uint64_t version = 1;
     if (dirty_db.size() > 0)
     {
         auto dirty_it = dirty_db.upper_bound((obj_ver_id){
@@ -33,10 +42,9 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
                 : ((dirty_it->second.state & BS_ST_WORKFLOW_MASK) == BS_ST_WAIT_BIG);
             if (!is_del && !deleted)
             {
-                if (dsk.clean_entry_bitmap_size > sizeof(void*))
-                    memcpy(bmp, dirty_it->second.bitmap, dsk.clean_entry_bitmap_size);
-                else
-                    bmp = dirty_it->second.bitmap;
+                void *dyn_from = alloc_dyn_data
+                    ? (uint8_t*)dirty_it->second.dyn_data + sizeof(int) : (uint8_t*)&dirty_it->second.dyn_data;
+                memcpy(dyn_ptr, dyn_from, dsk.clean_entry_bitmap_size);
             }
         }
     }
@@ -50,7 +58,7 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
             if (!is_del)
             {
                 void *bmp_ptr = get_clean_entry_bitmap(clean_it->second.location, dsk.clean_entry_bitmap_size);
-                memcpy((dsk.clean_entry_bitmap_size > sizeof(void*) ? bmp : &bmp), bmp_ptr, dsk.clean_entry_bitmap_size);
+                memcpy(dyn_ptr, bmp_ptr, dsk.clean_entry_bitmap_size);
             }
         }
         else
@@ -112,9 +120,9 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
             printf("Write %lx:%lx v%lu requested, but we already have v%lu\n", op->oid.inode, op->oid.stripe, op->version, version);
 #endif
             op->retval = -EEXIST;
-            if (!is_del && dsk.clean_entry_bitmap_size > sizeof(void*))
+            if (!is_del && alloc_dyn_data)
             {
-                free(bmp);
+                free(dyn);
             }
             return false;
         }
@@ -158,26 +166,50 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
         if (op->bitmap)
         {
             // Only allow to overwrite part of the object bitmap respective to the write's offset/len
-            uint8_t *bmp_ptr = (uint8_t*)(dsk.clean_entry_bitmap_size > sizeof(void*) ? bmp : &bmp);
             uint32_t bit = op->offset/dsk.bitmap_granularity;
             uint32_t bits_left = op->len/dsk.bitmap_granularity;
             while (!(bit % 8) && bits_left >= 8)
             {
                 // Copy bytes
-                bmp_ptr[bit/8] = ((uint8_t*)op->bitmap)[bit/8];
+                dyn_ptr[bit/8] = ((uint8_t*)op->bitmap)[bit/8];
                 bit += 8;
                 bits_left -= 8;
             }
             while (bits_left > 0)
             {
                 // Copy bits
-                bmp_ptr[bit/8] = (bmp_ptr[bit/8] & ~(1 << (bit%8)))
+                dyn_ptr[bit/8] = (dyn_ptr[bit/8] & ~(1 << (bit%8)))
                     | (((uint8_t*)op->bitmap)[bit/8] & (1 << bit%8));
                 bit++;
                 bits_left--;
             }
         }
     }
+    // Calculate checksums
+    // FIXME: Allow to receive checksums from outside?
+    if (!is_del && dsk.data_csum_type && op->len > 0)
+    {
+        uint32_t *data_csums = (uint32_t*)(dyn_ptr + dsk.clean_entry_bitmap_size);
+        uint32_t start = op->offset / dsk.csum_block_size;
+        uint32_t end = (op->offset+op->len-1) / dsk.csum_block_size;
+        auto fn = state & BS_ST_BIG_WRITE ? crc32c_pad : crc32c_nopad;
+        if (start == end)
+            data_csums[0] = fn(0, op->buf, op->len, op->offset - start*dsk.csum_block_size, end*dsk.csum_block_size - (op->offset+op->len));
+        else
+        {
+            // First block
+            data_csums[0] = fn(0, op->buf, dsk.csum_block_size*(start+1)-op->offset, op->offset - start*dsk.csum_block_size, 0);
+            // Intermediate blocks
+            for (uint32_t i = start+1; i < end; i++)
+                data_csums[i-start] = crc32c(0, (uint8_t*)op->buf + dsk.csum_block_size*i-op->offset, dsk.csum_block_size);
+            // Last block
+            data_csums[end-start] = fn(
+                0, (uint8_t*)op->buf + end*dsk.csum_block_size - op->offset,
+                op->offset+op->len - end*dsk.csum_block_size,
+                0, (end+1)*dsk.csum_block_size - (op->offset+op->len)
+            );
+        }
+    }
     dirty_db.emplace((obj_ver_id){
         .oid = op->oid,
         .version = op->version,
@@ -188,7 +220,7 @@ bool blockstore_impl_t::enqueue_write(blockstore_op_t *op)
         .offset = is_del ? 0 : op->offset,
         .len = is_del ? 0 : op->len,
         .journal_sector = 0,
-        .bitmap = bmp,
+        .dyn_data = dyn,
     });
     return true;
 }
@@ -197,8 +229,7 @@ void blockstore_impl_t::cancel_all_writes(blockstore_op_t *op, blockstore_dirty_
 {
     while (dirty_it != dirty_db.end() && dirty_it->first.oid == op->oid)
     {
-        if (dsk.clean_entry_bitmap_size > sizeof(void*))
-            free(dirty_it->second.bitmap);
+        free_dirty_dyn_data(dirty_it->second);
         dirty_db.erase(dirty_it++);
     }
     bool found = false;
@@ -255,13 +286,18 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
         printf("Restoring %lx:%lx version: v%lu -> v%lu\n", op->oid.inode, op->oid.stripe, op->version, PRIV(op)->real_version);
 #endif
         auto prev_it = dirty_it;
-        prev_it--;
-        if (prev_it->first.oid == op->oid && prev_it->first.version >= PRIV(op)->real_version)
+        if (prev_it != dirty_db.begin())
         {
-            // Original version is still invalid
-            // All subsequent writes to the same object must be canceled too
-            cancel_all_writes(op, dirty_it, -EEXIST);
-            return 2;
+            prev_it--;
+            if (prev_it->first.oid == op->oid && prev_it->first.version >= PRIV(op)->real_version)
+            {
+                // Original version is still invalid
+                // All subsequent writes to the same object must be canceled too
+                printf("Tried to write %lx:%lx v%lu after delete (old version v%lu), but already have v%lu\n",
+                    op->oid.inode, op->oid.stripe, PRIV(op)->real_version, op->version, prev_it->first.version);
+                cancel_all_writes(op, dirty_it, -EEXIST);
+                return 2;
+            }
         }
         op->version = PRIV(op)->real_version;
         PRIV(op)->real_version = 0;
@@ -280,7 +316,7 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
     {
         blockstore_journal_check_t space_check(this);
         if (!space_check.check_available(op, unsynced_big_write_count + 1,
-            sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size,
+            sizeof(journal_entry_big_write) + dsk.clean_dyn_size,
             (dirty_it->second.state & BS_ST_INSTANT) ? JOURNAL_INSTANT_RESERVATION : JOURNAL_STABILIZE_RESERVATION))
         {
             return 0;
@@ -347,7 +383,6 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
             sqe, dsk.data_fd, PRIV(op)->iov_zerofill, vcnt, dsk.data_offset + (loc << dsk.block_order) + op->offset - stripe_offset
         );
         PRIV(op)->pending_ops = 1;
-        PRIV(op)->min_flushed_journal_sector = PRIV(op)->max_flushed_journal_sector = 0;
         if (immediate_commit != IMMEDIATE_ALL)
         {
             // Increase the counter, but don't save into unsynced_writes yet (can't sync until the write is finished)
@@ -363,12 +398,13 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
     {
         // Small (journaled) write
         // First check if the journal has sufficient space
+        uint64_t dyn_size = dsk.dirty_dyn_size(op->offset, op->len);
         blockstore_journal_check_t space_check(this);
         if (unsynced_big_write_count &&
             !space_check.check_available(op, unsynced_big_write_count,
-                sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size, 0)
+                sizeof(journal_entry_big_write) + dsk.clean_dyn_size, 0)
             || !space_check.check_available(op, 1,
-                sizeof(journal_entry_small_write) + dsk.clean_entry_bitmap_size,
+                sizeof(journal_entry_small_write) + dyn_size,
                 op->len + ((dirty_it->second.state & BS_ST_INSTANT) ? JOURNAL_INSTANT_RESERVATION : JOURNAL_STABILIZE_RESERVATION)))
         {
             return 0;
@@ -377,27 +413,21 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
         BS_SUBMIT_CHECK_SQES(
             // Write current journal sector only if it's dirty and full, or in the immediate_commit mode
             (immediate_commit != IMMEDIATE_NONE ||
-                !journal.entry_fits(sizeof(journal_entry_small_write) + dsk.clean_entry_bitmap_size) ? 1 : 0) +
+                !journal.entry_fits(sizeof(journal_entry_small_write) + dyn_size) ? 1 : 0) +
             (op->len > 0 ? 1 : 0)
         );
         write_iodepth++;
         // Got SQEs. Prepare previous journal sector write if required
         auto cb = [this, op](ring_data_t *data) { handle_write_event(data, op); };
-        if (immediate_commit == IMMEDIATE_NONE)
+        if (immediate_commit == IMMEDIATE_NONE &&
+            !journal.entry_fits(sizeof(journal_entry_small_write) + dyn_size))
         {
-            if (!journal.entry_fits(sizeof(journal_entry_small_write) + dsk.clean_entry_bitmap_size))
-            {
-                prepare_journal_sector_write(journal.cur_sector, op);
-            }
-            else
-            {
-                PRIV(op)->min_flushed_journal_sector = PRIV(op)->max_flushed_journal_sector = 0;
-            }
+            prepare_journal_sector_write(journal.cur_sector, op);
         }
         // Then pre-fill journal entry
         journal_entry_small_write *je = (journal_entry_small_write*)prefill_single_journal_entry(
             journal, op->opcode == BS_OP_WRITE_STABLE ? JE_SMALL_WRITE_INSTANT : JE_SMALL_WRITE,
-            sizeof(journal_entry_small_write) + dsk.clean_entry_bitmap_size
+            sizeof(journal_entry_small_write) + dyn_size
         );
         dirty_it->second.journal_sector = journal.sector_info[journal.cur_sector].offset;
         journal.used_sectors[journal.sector_info[journal.cur_sector].offset]++;
@@ -431,8 +461,9 @@ int blockstore_impl_t::dequeue_write(blockstore_op_t *op)
         je->offset = op->offset;
         je->len = op->len;
         je->data_offset = journal.next_free;
-        je->crc32_data = crc32c(0, op->buf, op->len);
-        memcpy((void*)(je+1), (dsk.clean_entry_bitmap_size > sizeof(void*) ? dirty_it->second.bitmap : &dirty_it->second.bitmap), dsk.clean_entry_bitmap_size);
+        je->crc32_data = dsk.csum_block_size ? 0 : crc32c(0, op->buf, op->len);
+        memcpy((void*)(je+1), (alloc_dyn_data
+            ? (uint8_t*)dirty_it->second.dyn_data+sizeof(int) : (uint8_t*)&dirty_it->second.dyn_data), dyn_size);
         je->crc32 = je_crc32((journal_entry*)je);
         journal.crc32_last = je->crc32;
         if (immediate_commit != IMMEDIATE_NONE)
@@ -501,9 +532,9 @@ resume_2:
             .version = op->version,
         });
         assert(dirty_it != dirty_db.end());
+        uint64_t dyn_size = dsk.dirty_dyn_size(op->offset, op->len);
         blockstore_journal_check_t space_check(this);
-        if (!space_check.check_available(op, 1,
-            sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size,
+        if (!space_check.check_available(op, 1, sizeof(journal_entry_big_write) + dyn_size,
             ((dirty_it->second.state & BS_ST_INSTANT) ? JOURNAL_INSTANT_RESERVATION : JOURNAL_STABILIZE_RESERVATION)))
         {
             return 0;
@@ -511,7 +542,7 @@ resume_2:
         BS_SUBMIT_CHECK_SQES(1);
         journal_entry_big_write *je = (journal_entry_big_write*)prefill_single_journal_entry(
             journal, op->opcode == BS_OP_WRITE_STABLE ? JE_BIG_WRITE_INSTANT : JE_BIG_WRITE,
-            sizeof(journal_entry_big_write) + dsk.clean_entry_bitmap_size
+            sizeof(journal_entry_big_write) + dyn_size
         );
         dirty_it->second.journal_sector = journal.sector_info[journal.cur_sector].offset;
         journal.used_sectors[journal.sector_info[journal.cur_sector].offset]++;
@@ -527,7 +558,8 @@ resume_2:
         je->offset = op->offset;
         je->len = op->len;
         je->location = dirty_it->second.location;
-        memcpy((void*)(je+1), (dsk.clean_entry_bitmap_size > sizeof(void*) ? dirty_it->second.bitmap : &dirty_it->second.bitmap), dsk.clean_entry_bitmap_size);
+        memcpy((void*)(je+1), (alloc_dyn_data
+            ? (uint8_t*)dirty_it->second.dyn_data+sizeof(int) : (uint8_t*)&dirty_it->second.dyn_data), dyn_size);
         je->crc32 = je_crc32((journal_entry*)je);
         journal.crc32_last = je->crc32;
         prepare_journal_sector_write(journal.cur_sector, op);
@@ -661,8 +693,13 @@ void blockstore_impl_t::release_journal_sectors(blockstore_op_t *op)
         uint64_t s = PRIV(op)->min_flushed_journal_sector;
         while (1)
         {
-            if (s != (1+journal.cur_sector) && journal.sector_info[s-1].flush_count == 0)
+            if (!journal.sector_info[s-1].dirty && journal.sector_info[s-1].flush_count == 0)
             {
+                if (s == (1+journal.cur_sector))
+                {
+                    // Forcibly move to the next sector and move dirty position
+                    journal.in_sector_pos = journal.block_size;
+                }
                 // We know for sure that we won't write into this sector anymore
                 uint64_t new_ds = journal.sector_info[s-1].offset + journal.block_size;
                 if (new_ds >= journal.len)
@@ -711,17 +748,11 @@ int blockstore_impl_t::dequeue_del(blockstore_op_t *op)
     }
     write_iodepth++;
     // Prepare journal sector write
-    if (immediate_commit == IMMEDIATE_NONE)
+    if (immediate_commit == IMMEDIATE_NONE &&
+        (dsk.journal_block_size - journal.in_sector_pos) < sizeof(journal_entry_del) &&
+        journal.sector_info[journal.cur_sector].dirty)
     {
-        if ((dsk.journal_block_size - journal.in_sector_pos) < sizeof(journal_entry_del) &&
-            journal.sector_info[journal.cur_sector].dirty)
-        {
-            prepare_journal_sector_write(journal.cur_sector, op);
-        }
-        else
-        {
-            PRIV(op)->min_flushed_journal_sector = PRIV(op)->max_flushed_journal_sector = 0;
-        }
+        prepare_journal_sector_write(journal.cur_sector, op);
     }
     // Pre-fill journal entry
     journal_entry_del *je = (journal_entry_del*)prefill_single_journal_entry(

src/cli.cpp

@@ -357,6 +357,8 @@ static int run(cli_tool_t *p, json11::Json::object cfg)
         p->ringloop = NULL;
     }
     // Print result
+    fflush(stderr);
+    fflush(stdout);
     if (p->json_output && !result.data.is_null())
     {
         printf("%s\n", result.data.dump().c_str());

src/cli_alloc_osd.cpp

@@ -77,8 +77,8 @@ struct alloc_osd_t
                     std::string key = base64_decode(kv["key"].string_value());
                     osd_num_t cur_osd;
                     char null_byte = 0;
-                    sscanf(key.c_str() + parent->cli->st_cli.etcd_prefix.length(), "/osd/stats/%lu%c", &cur_osd, &null_byte);
-                    if (!cur_osd || null_byte != 0)
+                    int scanned = sscanf(key.c_str() + parent->cli->st_cli.etcd_prefix.length(), "/osd/stats/%lu%c", &cur_osd, &null_byte);
+                    if (scanned != 1 || !cur_osd)
                     {
                         fprintf(stderr, "Invalid key in etcd: %s\n", key.c_str());
                         continue;

src/cli_df.cpp

@@ -67,8 +67,8 @@ resume_1:
             // pool ID
             pool_id_t pool_id;
             char null_byte = 0;
-            sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(), "/pool/stats/%u%c", &pool_id, &null_byte);
-            if (!pool_id || pool_id >= POOL_ID_MAX || null_byte != 0)
+            int scanned = sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(), "/pool/stats/%u%c", &pool_id, &null_byte);
+            if (scanned != 1 || !pool_id || pool_id >= POOL_ID_MAX)
             {
                 fprintf(stderr, "Invalid key in etcd: %s\n", kv.key.c_str());
                 continue;
@@ -82,8 +82,8 @@ resume_1:
             // osd ID
             osd_num_t osd_num;
             char null_byte = 0;
-            sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(), "/osd/stats/%lu%c", &osd_num, &null_byte);
-            if (!osd_num || osd_num >= POOL_ID_MAX || null_byte != 0)
+            int scanned = sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(), "/osd/stats/%lu%c", &osd_num, &null_byte);
+            if (scanned != 1 || !osd_num || osd_num >= POOL_ID_MAX)
             {
                 fprintf(stderr, "Invalid key in etcd: %s\n", kv.key.c_str());
                 continue;

src/cli_ls.cpp

@@ -56,14 +56,15 @@ struct image_lister_t
             {
                 continue;
             }
-            auto & pool_cfg = parent->cli->st_cli.pool_config.at(INODE_POOL(ic.second.num));
+            auto pool_it = parent->cli->st_cli.pool_config.find(INODE_POOL(ic.second.num));
+            bool good_pool = pool_it != parent->cli->st_cli.pool_config.end();
             auto item = json11::Json::object {
                 { "name", ic.second.name },
                 { "size", ic.second.size },
                 { "used_size", 0 },
                 { "readonly", ic.second.readonly },
                 { "pool_id", (uint64_t)INODE_POOL(ic.second.num) },
-                { "pool_name", pool_cfg.name },
+                { "pool_name", good_pool ? pool_it->second.name : "? (ID:"+std::to_string(INODE_POOL(ic.second.num))+")" },
                 { "inode_num", INODE_NO_POOL(ic.second.num) },
                 { "inode_id", ic.second.num },
             };
@@ -132,8 +133,8 @@ resume_1:
             // pool ID
             pool_id_t pool_id;
             char null_byte = 0;
-            sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(), "/pool/stats/%u%c", &pool_id, &null_byte);
-            if (!pool_id || pool_id >= POOL_ID_MAX || null_byte != 0)
+            int scanned = sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(), "/pool/stats/%u%c", &pool_id, &null_byte);
+            if (scanned != 1 || !pool_id || pool_id >= POOL_ID_MAX)
             {
                 fprintf(stderr, "Invalid key in etcd: %s\n", kv.key.c_str());
                 continue;
@@ -148,9 +149,9 @@ resume_1:
             pool_id_t pool_id;
             inode_t only_inode_num;
             char null_byte = 0;
-            sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(),
+            int scanned = sscanf(kv.key.substr(parent->cli->st_cli.etcd_prefix.length()).c_str(),
                 "/inode/stats/%u/%lu%c", &pool_id, &only_inode_num, &null_byte);
-            if (!pool_id || pool_id >= POOL_ID_MAX || INODE_POOL(only_inode_num) != 0 || null_byte != 0)
+            if (scanned != 2 || !pool_id || pool_id >= POOL_ID_MAX || INODE_POOL(only_inode_num) != 0)
             {
                 fprintf(stderr, "Invalid key in etcd: %s\n", kv.key.c_str());
                 continue;
@@ -173,7 +174,7 @@ resume_1:
                     { "size", 0 },
                     { "readonly", false },
                     { "pool_id", (uint64_t)INODE_POOL(inode_num) },
-                    { "pool_name", pool_it == parent->cli->st_cli.pool_config.end()
+                    { "pool_name", pool_it != parent->cli->st_cli.pool_config.end()
                         ? (pool_it->second.name == "" ? "<Unnamed>" : pool_it->second.name) : "?" },
                     { "inode_num", INODE_NO_POOL(inode_num) },
                     { "inode_id", inode_num },
@@ -247,6 +248,8 @@ resume_1:
         if (state == 1)
             goto resume_1;
         get_list();
+        if (state == 100)
+            return;
         if (show_stats)
         {
 resume_1:
@@ -269,7 +272,7 @@ resume_1:
             { "key", "name" },
             { "title", "NAME" },
         });
-        if (!list_pool_id)
+        if (list_pool_name == "")
         {
             cols.push_back(json11::Json::object{
                 { "key", "pool_name" },
@@ -376,16 +379,18 @@ resume_1:
 
 std::string print_table(json11::Json items, json11::Json header, bool use_esc)
 {
+    int header_sizes[header.array_items().size()];
     std::vector<int> sizes;
     for (int i = 0; i < header.array_items().size(); i++)
     {
-        sizes.push_back(header[i]["title"].string_value().length());
+        header_sizes[i] = utf8_length(header[i]["title"].string_value());
+        sizes.push_back(header_sizes[i]);
     }
     for (auto & item: items.array_items())
     {
         for (int i = 0; i < header.array_items().size(); i++)
         {
-            int l = item[header[i]["key"].string_value()].as_string().length();
+            int l = utf8_length(item[header[i]["key"].string_value()].as_string());
             sizes[i] = sizes[i] < l ? l : sizes[i];
         }
     }
@@ -397,7 +402,7 @@ std::string print_table(json11::Json items, json11::Json header, bool use_esc)
             // Separator
             str += "  ";
         }
-        int pad = sizes[i]-header[i]["title"].string_value().length();
+        int pad = sizes[i]-header_sizes[i];
         if (header[i]["right"].bool_value())
         {
             // Align right
@@ -425,7 +430,7 @@ std::string print_table(json11::Json items, json11::Json header, bool use_esc)
                 // Separator
                 str += "  ";
             }
-            int pad = sizes[i] - item[header[i]["key"].string_value()].as_string().length();
+            int pad = sizes[i] - utf8_length(item[header[i]["key"].string_value()].as_string());
             if (header[i]["right"].bool_value())
             {
                 // Align right

src/cli_merge.cpp

@@ -41,7 +41,7 @@ struct snap_merger_t
     int fsync_interval = 128;
 
     // -- STATE --
-    inode_t target;
+    inode_t target, to_num;
     int target_rank;
     bool inside_continue = false;
     int state = 0;
@@ -98,6 +98,7 @@ struct snap_merger_t
             state = 100;
             return;
         }
+        to_num = to_cfg->num;
         // Check that to_cfg is actually a child of from_cfg and target_cfg is somewhere between them
         std::vector<inode_t> chain_list;
         inode_config_t *cur = to_cfg;
@@ -451,7 +452,7 @@ struct snap_merger_t
     {
         cluster_op_t *op = &rwo->op;
         op->opcode = OSD_OP_READ;
-        op->inode = target;
+        op->inode = to_num;
         op->offset = rwo->offset;
         op->len = target_block_size;
         op->iov.push_back(rwo->buf, target_block_size);
@@ -483,7 +484,7 @@ struct snap_merger_t
                 {
                     // write start->end
                     rwo->todo++;
-                    write_subop(rwo, rwo->start*gran, rwo->end*gran, use_cas ? 1+rwo->op.version : 0);
+                    write_subop(rwo, rwo->start*gran, rwo->end*gran, use_cas && to_num == target ? 1+rwo->op.version : 0);
                     rwo->start = rwo->end;
                     if (use_cas)
                     {
@@ -502,7 +503,7 @@ struct snap_merger_t
         {
             // write start->end
             rwo->todo++;
-            write_subop(rwo, rwo->start*gran, rwo->end*gran, use_cas ? 1+rwo->op.version : 0);
+            write_subop(rwo, rwo->start*gran, rwo->end*gran, use_cas && to_num == target ? 1+rwo->op.version : 0);
             rwo->start = rwo->end;
             if (use_cas)
             {
@@ -532,7 +533,7 @@ struct snap_merger_t
                 if (use_cas && subop->retval == -EINTR)
                 {
                     // CAS failure - reread and repeat optimistically
-                    rwo->start = subop->offset - rwo->offset;
+                    rwo->start = rwo->end = 0;
                     rwo_read(rwo);
                     delete subop;
                     return;
@@ -542,7 +543,7 @@ struct snap_merger_t
                 rwo->error_read = false;
             }
             // Increment CAS version
-            rwo->op.version++;
+            rwo->op.version = subop->version;
             if (use_cas)
                 next_write(rwo);
             else

src/cli_modify.cpp

@@ -13,7 +13,7 @@ struct image_changer_t
     std::string image_name;
     std::string new_name;
     uint64_t new_size = 0;
-    bool force_size = false;
+    bool force_size = false, inc_size = false;
     bool set_readonly = false, set_readwrite = false, force = false;
     // interval between fsyncs
     int fsync_interval = 128;
@@ -81,14 +81,14 @@ struct image_changer_t
         }
         if ((!set_readwrite || !cfg.readonly) &&
             (!set_readonly || cfg.readonly) &&
-            (!new_size && !force_size || cfg.size == new_size) &&
+            (!new_size && !force_size || cfg.size == new_size || cfg.size >= new_size && inc_size) &&
             (new_name == "" || new_name == image_name))
         {
             result = (cli_result_t){ .text = "No change" };
             state = 100;
             return;
         }
-        if (new_size != 0 || force_size)
+        if ((new_size != 0 || force_size) && (cfg.size < new_size || !inc_size))
         {
             if (cfg.size >= new_size)
             {
@@ -233,6 +233,7 @@ std::function<bool(cli_result_t &)> cli_tool_t::start_modify(json11::Json cfg)
     changer->new_name = cfg["rename"].string_value();
     changer->new_size = parse_size(cfg["resize"].as_string());
     changer->force_size = cfg["force_size"].bool_value();
+    changer->inc_size = cfg["inc_size"].bool_value();
     changer->force = cfg["force"].bool_value();
     changer->set_readonly = cfg["readonly"].bool_value();
     changer->set_readwrite = cfg["readwrite"].bool_value();

src/cli_rm.cpp

@@ -65,6 +65,9 @@ struct snap_remover_t
     int current_child = 0;
     std::function<bool(cli_result_t &)> cb;
 
+    std::vector<std::string> rebased_images, deleted_images;
+    std::vector<uint64_t> deleted_ids;
+    std::string inverse_child_name, inverse_parent_name;
     cli_result_t result;
 
     bool is_done()
@@ -122,6 +125,7 @@ resume_1:
         {
             if (merge_children[current_child] == inverse_child)
                 continue;
+            rebased_images.push_back(parent->cli->st_cli.inode_config.at(merge_children[current_child]).name);
             start_merge_child(merge_children[current_child], merge_children[current_child]);
             if (state == 100)
                 return;
@@ -134,9 +138,12 @@ resume_2:
             cb = NULL;
             if (result.err)
             {
+                result.data = my_result(result.data);
                 state = 100;
                 return;
             }
+            else if (parent->progress)
+                printf("%s\n", result.text.c_str());
             parent->change_parent(merge_children[current_child], new_parent, &result);
             state = 3;
 resume_3:
@@ -144,6 +151,7 @@ resume_3:
                 return;
             if (result.err)
             {
+                result.data = my_result(result.data);
                 state = 100;
                 return;
             }
@@ -165,9 +173,12 @@ resume_4:
             cb = NULL;
             if (result.err)
             {
+                result.data = my_result(result.data);
                 state = 100;
                 return;
             }
+            else if (parent->progress)
+                printf("%s\n", result.text.c_str());
             // Delete "inverse" child data
             start_delete_source(inverse_child);
             if (state == 100)
@@ -181,9 +192,12 @@ resume_5:
             cb = NULL;
             if (result.err)
             {
+                result.data = my_result(result.data);
                 state = 100;
                 return;
             }
+            else if (parent->progress)
+                printf("%s\n", result.text.c_str());
             // Delete "inverse" child metadata, rename parent over it,
             // and also change parent links of the previous "inverse" child
             rename_inverse_parent();
@@ -199,6 +213,12 @@ resume_6:
         {
             if (chain_list[current_child] == inverse_parent)
                 continue;
+            {
+                auto parent_it = parent->cli->st_cli.inode_config.find(chain_list[current_child]);
+                if (parent_it != parent->cli->st_cli.inode_config.end())
+                    deleted_images.push_back(parent_it->second.name);
+                deleted_ids.push_back(chain_list[current_child]);
+            }
             start_delete_source(chain_list[current_child]);
 resume_7:
             while (!cb(result))
@@ -209,9 +229,12 @@ resume_7:
             cb = NULL;
             if (result.err)
             {
+                result.data = my_result(result.data);
                 state = 100;
                 return;
             }
+            else if (parent->progress)
+                printf("%s\n", result.text.c_str());
             delete_inode_config(chain_list[current_child]);
             if (state == 100)
                 return;
@@ -221,11 +244,26 @@ resume_8:
                 return;
         }
         state = 100;
+        result = (cli_result_t){
+            .text = "",
+            .data = my_result(result.data),
+        };
 resume_100:
         // Done
         return;
     }
 
+    json11::Json my_result(json11::Json src)
+    {
+        auto obj = src.object_items();
+        obj["deleted_ids"] = deleted_ids;
+        obj["deleted_images"] = deleted_images;
+        obj["rebased_images"] = rebased_images;
+        obj["renamed_from"] = inverse_parent_name;
+        obj["renamed_to"] = inverse_child_name;
+        return obj;
+    }
+
     void get_merge_children()
     {
         // Get all children of from..to
@@ -338,12 +376,16 @@ resume_100:
             }
             for (auto inode_result: data["responses"].array_items())
             {
-                auto kv = parent->cli->st_cli.parse_etcd_kv(inode_result["kvs"][0]);
+                if (inode_result["response_range"]["kvs"].array_items().size() == 0)
+                {
+                    continue;
+                }
+                auto kv = parent->cli->st_cli.parse_etcd_kv(inode_result["response_range"]["kvs"][0]);
                 pool_id_t pool_id = 0;
                 inode_t inode = 0;
                 char null_byte = 0;
-                sscanf(kv.key.c_str() + parent->cli->st_cli.etcd_prefix.length()+13, "%u/%lu%c", &pool_id, &inode, &null_byte);
-                if (!inode || null_byte != 0)
+                int scanned = sscanf(kv.key.c_str() + parent->cli->st_cli.etcd_prefix.length()+13, "%u/%lu%c", &pool_id, &inode, &null_byte);
+                if (scanned != 2 || !inode)
                 {
                     result = (cli_result_t){ .err = EIO, .text = "Bad key returned from etcd: "+kv.key };
                     state = 100;
@@ -377,7 +419,7 @@ resume_100:
             inode_t child = cp.first;
             uint64_t child_used = inode_used[child];
             int rank = cp.second;
-            for (int i = chain_list.size()-rank; i < chain_list.size(); i++)
+            for (int i = chain_list.size()-1-rank; i < chain_list.size(); i++)
             {
                 inode_t parent = chain_list[i];
                 uint64_t parent_used = inode_used[parent];
@@ -413,8 +455,8 @@ resume_100:
         }
         inode_config_t *child_cfg = &child_it->second;
         inode_config_t *target_cfg = &target_it->second;
-        std::string child_name = child_cfg->name;
-        std::string target_name = target_cfg->name;
+        inverse_child_name = child_cfg->name;
+        inverse_parent_name = target_cfg->name;
         std::string child_cfg_key = base64_encode(
             parent->cli->st_cli.etcd_prefix+
             "/config/inode/"+std::to_string(INODE_POOL(inverse_child))+
@@ -425,6 +467,9 @@ resume_100:
             "/config/inode/"+std::to_string(INODE_POOL(inverse_parent))+
             "/"+std::to_string(INODE_NO_POOL(inverse_parent))
         );
+        std::string target_idx_key = base64_encode(
+            parent->cli->st_cli.etcd_prefix+"/index/image/"+inverse_parent_name
+        );
         // Fill new configuration
         inode_config_t new_cfg = *child_cfg;
         new_cfg.num = target_cfg->num;
@@ -449,6 +494,11 @@ resume_100:
                     { "key", child_cfg_key },
                 } },
             },
+            json11::Json::object {
+                { "request_delete_range", json11::Json::object {
+                    { "key", target_idx_key },
+                } },
+            },
             json11::Json::object {
                 { "request_put", json11::Json::object {
                     { "key", target_cfg_key },
@@ -495,12 +545,12 @@ resume_100:
         parent->cli->st_cli.etcd_txn_slow(json11::Json::object {
             { "compare", cmp },
             { "success", txn },
-        }, [this, target_name, child_name](std::string err, json11::Json res)
+        }, [this](std::string err, json11::Json res)
         {
             parent->waiting--;
             if (err != "")
             {
-                result = (cli_result_t){ .err = EIO, .text = "Error renaming "+target_name+" to "+child_name+": "+err };
+                result = (cli_result_t){ .err = EIO, .text = "Error renaming "+inverse_parent_name+" to "+inverse_child_name+": "+err };
                 state = 100;
                 return;
             }
@@ -508,14 +558,14 @@ resume_100:
             {
                 result = (cli_result_t){
                     .err = EAGAIN,
-                    .text = "Parent ("+target_name+"), child ("+child_name+"), or one of its children"
+                    .text = "Parent ("+inverse_parent_name+"), child ("+inverse_child_name+"), or one of its children"
                         " configuration was modified during rename",
                 };
                 state = 100;
                 return;
             }
             if (parent->progress)
-                printf("Layer %s renamed to %s\n", target_name.c_str(), child_name.c_str());
+                printf("Layer %s renamed to %s\n", inverse_parent_name.c_str(), inverse_child_name.c_str());
             parent->ringloop->wakeup();
         });
     }

src/cli_rm_data.cpp

@@ -28,6 +28,7 @@ struct rm_inode_t
     cli_tool_t *parent = NULL;
     inode_list_t *lister = NULL;
     std::vector<rm_pg_t*> lists;
+    std::vector<osd_num_t> inactive_osds;
     uint64_t total_count = 0, total_done = 0, total_prev_pct = 0;
     uint64_t pgs_to_list = 0;
     bool lists_done = false;
@@ -86,6 +87,16 @@ struct rm_inode_t
             state = 100;
             return;
         }
+        inactive_osds = parent->cli->list_inode_get_inactive_osds(lister);
+        if (inactive_osds.size() && !parent->json_output)
+        {
+            fprintf(stderr, "Some data may remain after delete on OSDs which are currently down: ");
+            for (int i = 0; i < inactive_osds.size(); i++)
+            {
+                fprintf(stderr, i > 0 ? ", %lu" : "%lu", inactive_osds[i]);
+            }
+            fprintf(stderr, "\n");
+        }
         pgs_to_list = parent->cli->list_pg_count(lister);
         parent->cli->list_inode_next(lister, parent->parallel_osds);
     }
@@ -167,16 +178,33 @@ struct rm_inode_t
         }
         if (parent->progress && total_count > 0 && total_done*1000/total_count != total_prev_pct)
         {
-            printf("\rRemoved %lu/%lu objects, %lu more PGs to list...", total_done, total_count, pgs_to_list);
+            fprintf(stderr, "\rRemoved %lu/%lu objects, %lu more PGs to list...", total_done, total_count, pgs_to_list);
             total_prev_pct = total_done*1000/total_count;
         }
         if (lists_done && !lists.size())
         {
+            if (parent->progress && total_count > 0)
+            {
+                fprintf(stderr, "\n");
+            }
+            if (parent->progress && (total_done < total_count || inactive_osds.size() > 0))
+            {
+                fprintf(
+                    stderr, "Warning: Pool:%u,ID:%lu inode data may not have been fully removed.\n"
+                    " Use `vitastor-cli rm-data --pool %u --inode %lu` if you encounter it in listings.\n",
+                    pool_id, INODE_NO_POOL(inode), pool_id, INODE_NO_POOL(inode)
+                );
+            }
             result = (cli_result_t){
                 .err = error_count > 0 ? EIO : 0,
                 .text = error_count > 0 ? "Some blocks were not removed" : (
                     "Done, inode "+std::to_string(INODE_NO_POOL(inode))+" from pool "+
                     std::to_string(pool_id)+" removed"),
+                .data = json11::Json::object {
+                    { "removed_objects", total_done },
+                    { "total_objects", total_count },
+                    { "inactive_osds", inactive_osds },
+                },
             };
             state = 100;
         }

src/cli_status.cpp

@@ -132,8 +132,8 @@ resume_2:
             auto kv = parent->cli->st_cli.parse_etcd_kv(osd_stats[i]);
             osd_num_t stat_osd_num = 0;
             char null_byte = 0;
-            sscanf(kv.key.c_str() + parent->cli->st_cli.etcd_prefix.size(), "/osd/stats/%lu%c", &stat_osd_num, &null_byte);
-            if (!stat_osd_num || null_byte != 0)
+            int scanned = sscanf(kv.key.c_str() + parent->cli->st_cli.etcd_prefix.size(), "/osd/stats/%lu%c", &stat_osd_num, &null_byte);
+            if (scanned != 1 || !stat_osd_num)
             {
                 fprintf(stderr, "Invalid key in etcd: %s\n", kv.key.c_str());
                 continue;

src/cluster_client.cpp

@@ -565,11 +565,11 @@ void cluster_client_t::copy_write(cluster_op_t *op, std::map<object_id, cluster_
     while (len > 0)
     {
         uint64_t new_len = 0;
-        if (dirty_it == dirty_buffers.end())
+        if (dirty_it == dirty_buffers.end() || dirty_it->first.inode != op->inode)
         {
             new_len = len;
         }
-        else if (dirty_it->first.inode != op->inode || dirty_it->first.stripe > pos)
+        else if (dirty_it->first.stripe > pos)
         {
             new_len = dirty_it->first.stripe - pos;
             if (new_len > len)
@@ -881,6 +881,7 @@ void cluster_client_t::slice_rw(cluster_op_t *op)
         uint64_t end = (op->offset + op->len) > (stripe + pg_block_size)
             ? (stripe + pg_block_size) : (op->offset + op->len);
         op->parts[i].iov.reset();
+        op->parts[i].flags = 0;
         if (op->cur_inode != op->inode)
         {
             // Read remaining parts from upper layers
@@ -918,7 +919,10 @@ void cluster_client_t::slice_rw(cluster_op_t *op)
             else
                 add_iov(cur-prev, skip_prev, op, iov_idx, iov_pos, op->parts[i].iov, scrap_buffer, scrap_buffer_size);
             if (end == begin)
+            {
                 op->done_count++;
+                op->parts[i].flags = PART_DONE;
+            }
         }
         else if (op->opcode != OSD_OP_READ_BITMAP && op->opcode != OSD_OP_READ_CHAIN_BITMAP && op->opcode != OSD_OP_DELETE)
         {
@@ -930,7 +934,6 @@ void cluster_client_t::slice_rw(cluster_op_t *op)
             op->opcode == OSD_OP_DELETE ? 0 : (uint32_t)(end - begin);
         op->parts[i].pg_num = pg_num;
         op->parts[i].osd_num = 0;
-        op->parts[i].flags = 0;
         i++;
     }
 }
@@ -1209,6 +1212,10 @@ void cluster_client_t::handle_op_part(cluster_op_part_t *part)
             copy_part_bitmap(op, part);
             op->version = op->parts.size() == 1 ? part->op.reply.rw.version : 0;
         }
+        else if (op->opcode == OSD_OP_WRITE)
+        {
+            op->version = op->parts.size() == 1 ? part->op.reply.rw.version : 0;
+        }
         if (op->inflight_count == 0)
         {
             if (op->opcode == OSD_OP_SYNC)

src/cluster_client.h

@@ -130,6 +130,7 @@ public:
     inode_list_t *list_inode_start(inode_t inode,
         std::function<void(inode_list_t* lst, std::set<object_id>&& objects, pg_num_t pg_num, osd_num_t primary_osd, int status)> callback);
     int list_pg_count(inode_list_t *lst);
+    const std::vector<osd_num_t> & list_inode_get_inactive_osds(inode_list_t *lst);
     void list_inode_next(inode_list_t *lst, int next_pgs);
     //inline uint32_t get_bs_bitmap_granularity() { return st_cli.global_bitmap_granularity; }
     //inline uint64_t get_bs_block_size() { return st_cli.global_block_size; }

src/cluster_client_list.cpp

@@ -36,6 +36,7 @@ struct inode_list_t
     inode_t inode = 0;
     int done_pgs = 0;
     int want = 0;
+    std::vector<osd_num_t> inactive_osds;
     std::vector<inode_list_pg_t*> pgs;
     std::function<void(inode_list_t* lst, std::set<object_id>&& objects, pg_num_t pg_num, osd_num_t primary_osd, int status)> callback;
 };
@@ -60,6 +61,7 @@ inode_list_t* cluster_client_t::list_inode_start(inode_t inode,
     lst->inode = inode;
     lst->callback = callback;
     auto pool_cfg = st_cli.pool_config[pool_id];
+    std::set<osd_num_t> inactive_osd_set;
     for (auto & pg_item: pool_cfg.pg_config)
     {
         auto & pg = pg_item.second;
@@ -106,11 +108,18 @@ inode_list_t* cluster_client_t::list_inode_start(inode_t inode,
             }
             for (osd_num_t peer_osd: all_peers)
             {
-                r->list_osds.push_back((inode_list_osd_t){
-                    .pg = r,
-                    .osd_num = peer_osd,
-                    .sent = false,
-                });
+                if (st_cli.peer_states.find(peer_osd) != st_cli.peer_states.end())
+                {
+                    r->list_osds.push_back((inode_list_osd_t){
+                        .pg = r,
+                        .osd_num = peer_osd,
+                        .sent = false,
+                    });
+                }
+                else
+                {
+                    inactive_osd_set.insert(peer_osd);
+                }
             }
         }
         else
@@ -132,6 +141,7 @@ inode_list_t* cluster_client_t::list_inode_start(inode_t inode,
     {
         lst->pgs[i]->pos = i;
     }
+    lst->inactive_osds.insert(lst->inactive_osds.end(), inactive_osd_set.begin(), inactive_osd_set.end());
     lists.push_back(lst);
     return lst;
 }
@@ -141,6 +151,11 @@ int cluster_client_t::list_pg_count(inode_list_t *lst)
     return lst->pgs.size();
 }
 
+const std::vector<osd_num_t> & cluster_client_t::list_inode_get_inactive_osds(inode_list_t *lst)
+{
+    return lst->inactive_osds;
+}
+
 void cluster_client_t::list_inode_next(inode_list_t *lst, int next_pgs)
 {
     if (next_pgs >= 0)

src/disk_simple_offsets.cpp

@@ -10,6 +10,7 @@
 #include "json11/json11.hpp"
 #include "str_util.h"
 #include "blockstore.h"
+#include "blockstore_disk.h"
 
 // Calculate offsets for a block device and print OSD command line parameters
 void disk_tool_simple_offsets(json11::Json cfg, bool json_output)
@@ -20,23 +21,39 @@ void disk_tool_simple_offsets(json11::Json cfg, bool json_output)
         fprintf(stderr, "Device path is missing\n");
         exit(1);
     }
-    uint64_t object_size = parse_size(cfg["object_size"].string_value());
+    uint64_t data_block_size = parse_size(cfg["object_size"].string_value());
     uint64_t bitmap_granularity = parse_size(cfg["bitmap_granularity"].string_value());
     uint64_t journal_size = parse_size(cfg["journal_size"].string_value());
     uint64_t device_block_size = parse_size(cfg["device_block_size"].string_value());
     uint64_t journal_offset = parse_size(cfg["journal_offset"].string_value());
     uint64_t device_size = parse_size(cfg["device_size"].string_value());
+    uint32_t csum_block_size = parse_size(cfg["csum_block_size"].string_value());
+    uint32_t data_csum_type = BLOCKSTORE_CSUM_NONE;
+    if (cfg["data_csum_type"] == "crc32c")
+        data_csum_type = BLOCKSTORE_CSUM_CRC32C;
+    else if (cfg["data_csum_type"].string_value() != "" && cfg["data_csum_type"].string_value() != "none")
+    {
+        fprintf(
+            stderr, "data_csum_type=%s is unsupported, only \"crc32c\" and \"none\" are supported",
+            cfg["data_csum_type"].string_value().c_str()
+        );
+        exit(1);
+    }
     std::string format = cfg["format"].string_value();
     if (json_output)
         format = "json";
-    if (!object_size)
-        object_size = 1 << DEFAULT_DATA_BLOCK_ORDER;
+    if (!data_block_size)
+        data_block_size = 1 << DEFAULT_DATA_BLOCK_ORDER;
     if (!bitmap_granularity)
         bitmap_granularity = DEFAULT_BITMAP_GRANULARITY;
     if (!journal_size)
         journal_size = 16*1024*1024;
     if (!device_block_size)
         device_block_size = 4096;
+    if (!data_csum_type)
+        csum_block_size = 0;
+    else if (!csum_block_size)
+        csum_block_size = bitmap_granularity;
     uint64_t orig_device_size = device_size;
     if (!device_size)
     {
@@ -85,22 +102,30 @@ void disk_tool_simple_offsets(json11::Json cfg, bool json_output)
         fprintf(stderr, "Invalid device block size specified: %lu\n", device_block_size);
         exit(1);
     }
-    if (object_size < device_block_size || object_size > MAX_DATA_BLOCK_SIZE ||
-        object_size & (object_size-1) != 0)
+    if (data_block_size < device_block_size || data_block_size > MAX_DATA_BLOCK_SIZE ||
+        data_block_size & (data_block_size-1) != 0)
     {
-        fprintf(stderr, "Invalid object size specified: %lu\n", object_size);
+        fprintf(stderr, "Invalid object size specified: %lu\n", data_block_size);
         exit(1);
     }
-    if (bitmap_granularity < device_block_size || bitmap_granularity > object_size ||
+    if (bitmap_granularity < device_block_size || bitmap_granularity > data_block_size ||
         bitmap_granularity & (bitmap_granularity-1) != 0)
     {
         fprintf(stderr, "Invalid bitmap granularity specified: %lu\n", bitmap_granularity);
         exit(1);
     }
+    if (csum_block_size && (data_block_size % csum_block_size))
+    {
+        fprintf(stderr, "csum_block_size must be a divisor of data_block_size\n");
+        exit(1);
+    }
     journal_offset = ((journal_offset+device_block_size-1)/device_block_size)*device_block_size;
     uint64_t meta_offset = journal_offset + ((journal_size+device_block_size-1)/device_block_size)*device_block_size;
-    uint64_t entries_per_block = (device_block_size / (24 + 2*object_size/bitmap_granularity/8));
-    uint64_t object_count = ((device_size-meta_offset)/object_size);
+    uint64_t data_csum_size = (data_csum_type ? data_block_size/csum_block_size*(data_csum_type & 0xFF) : 0);
+    uint64_t clean_entry_bitmap_size = data_block_size/bitmap_granularity/8;
+    uint64_t clean_entry_size = 24 /*sizeof(clean_disk_entry)*/ + 2*clean_entry_bitmap_size + data_csum_size + 4 /*entry_csum*/;
+    uint64_t entries_per_block = device_block_size / clean_entry_size;
+    uint64_t object_count = ((device_size-meta_offset)/data_block_size);
     uint64_t meta_size = (1 + (object_count+entries_per_block-1)/entries_per_block) * device_block_size;
     uint64_t data_offset = meta_offset + meta_size;
     if (format == "json")