From ea632367e991a94fc4de3071c5917ad23058c800 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Fri, 1 Jul 2022 11:43:28 +0300
Subject: [PATCH] Do not alter dsk.meta_offset/len to skip superblock

---
 src/blockstore_flush.cpp | 6 +++---
 src/blockstore_init.cpp  | 9 ++++-----
 src/blockstore_init.h    | 2 +-
 3 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/src/blockstore_flush.cpp b/src/blockstore_flush.cpp
index 36aff9ab..5781c1ca 100644
--- a/src/blockstore_flush.cpp
+++ b/src/blockstore_flush.cpp
@@ -541,7 +541,7 @@ resume_1:
             data->iov = (struct iovec){ meta_old.buf, bs->dsk.meta_block_size };
             data->callback = simple_callback_w;
             my_uring_prep_writev(
-                sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + meta_old.sector
+                sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bs->dsk.meta_block_size + meta_old.sector
             );
             wait_count++;
         }
@@ -585,7 +585,7 @@ resume_1:
         data->iov = (struct iovec){ meta_new.buf, bs->dsk.meta_block_size };
         data->callback = simple_callback_w;
         my_uring_prep_writev(
-            sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + meta_new.sector
+            sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bs->dsk.meta_block_size + meta_new.sector
         );
         wait_count++;
     resume_7:
@@ -849,7 +849,7 @@ bool journal_flusher_co::modify_meta_read(uint64_t meta_loc, flusher_meta_write_
         data->callback = simple_callback_r;
         wr.submitted = true;
         my_uring_prep_readv(
-            sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + wr.sector
+            sqe, bs->dsk.meta_fd, &data->iov, 1, bs->dsk.meta_offset + bs->dsk.meta_block_size + wr.sector
         );
         wait_count++;
     }
diff --git a/src/blockstore_init.cpp b/src/blockstore_init.cpp
index 2dad747a..12e53e43 100644
--- a/src/blockstore_init.cpp
+++ b/src/blockstore_init.cpp
@@ -130,12 +130,11 @@ resume_1:
         }
     }
     // Skip superblock
-    bs->dsk.meta_offset += bs->dsk.meta_block_size;
-    bs->dsk.meta_len -= bs->dsk.meta_block_size;
+    md_offset = bs->dsk.meta_block_size;
+    metadata_read = bs->dsk.meta_block_size;
     prev_done = 0;
     done_len = 0;
     done_pos = 0;
-    metadata_read = 0;
     // Read the rest of the metadata
     while (1)
     {
@@ -150,7 +149,7 @@ resume_1:
             GET_SQE();
             data->iov = {
                 (uint8_t*)metadata_buffer + (bs->inmemory_meta
-                    ? metadata_read
+                    ? metadata_read-md_offset
                     : (prev == 1 ? bs->metadata_buf_size : 0)),
                 bs->dsk.meta_len - metadata_read > bs->metadata_buf_size ? bs->metadata_buf_size : bs->dsk.meta_len - metadata_read,
             };
@@ -170,7 +169,7 @@ resume_1:
         if (prev_done)
         {
             void *done_buf = bs->inmemory_meta
-                ? ((uint8_t*)metadata_buffer + done_pos)
+                ? ((uint8_t*)metadata_buffer + done_pos-md_offset)
                 : ((uint8_t*)metadata_buffer + (prev_done == 2 ? bs->metadata_buf_size : 0));
             unsigned count = bs->dsk.meta_block_size / bs->dsk.clean_entry_size;
             for (int sector = 0; sector < done_len; sector += bs->dsk.meta_block_size)
diff --git a/src/blockstore_init.h b/src/blockstore_init.h
index 8b315565..8c66dfee 100644
--- a/src/blockstore_init.h
+++ b/src/blockstore_init.h
@@ -9,7 +9,7 @@ class blockstore_init_meta
     int wait_state = 0;
     bool zero_on_init = false;
     void *metadata_buffer = NULL;
-    uint64_t metadata_read = 0;
+    uint64_t metadata_read = 0, md_offset = 0;
     int prev = 0, prev_done = 0, done_len = 0, submitted = 0;
     uint64_t done_cnt = 0, done_pos = 0;
     uint64_t entries_loaded = 0;