Commit Graph

4532 Commits (05273a43af5f9e71152ad1b877bc3a898857e989)

Author SHA1 Message Date
Vladimir Sementsov-Ogievskiy 5deb6cbd1f block/dirty-bitmap: add bs link
Add bs field to BdrvDirtyBitmap structure. Drop BlockDriverState
parameter from bitmap APIs where possible.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190916141911.5255-3-vsementsov@virtuozzo.com
[Rebased on top of block-copy. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy 767db3aad8 block/dirty-bitmap: drop meta
Drop meta bitmaps, as they are unused.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190916141911.5255-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy d2c3080e41 block/qcow2: proper locking on bitmap add/remove paths
qmp_block_dirty_bitmap_add and do_block_dirty_bitmap_remove do acquire
aio context since 0a6c86d024. But this is not enough: we also must
lock qcow2 mutex when access in-image metadata. Especially it concerns
freeing qcow2 clusters.

To achieve this, move qcow2_can_store_new_dirty_bitmap and
qcow2_remove_persistent_dirty_bitmap to coroutine context.

Since we work in coroutines in correct aio context, we don't need
context acquiring in blockdev.c anymore, drop it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190920082543.23444-4-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy b56a1e3175 block/dirty-bitmap: return int from bdrv_remove_persistent_dirty_bitmap
It's more comfortable to not deal with local_err.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190920082543.23444-3-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy 85cc8a4f6b block: move bdrv_can_store_new_dirty_bitmap to block/dirty-bitmap.c
block/dirty-bitmap.c seems to be more appropriate for it and
bdrv_remove_persistent_dirty_bitmap already in it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190920082543.23444-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Max Reitz d1b9d19f99 qcow2: Limit total allocation range to INT_MAX
When the COW areas are included, the size of an allocation can exceed
INT_MAX.  This is kind of limited by handle_alloc() in that it already
caps avail_bytes at INT_MAX, but the number of clusters still reflects
the original length.

This can have all sorts of effects, ranging from the storage layer write
call failing to image corruption.  (If there were no image corruption,
then I suppose there would be data loss because the .cow_end area is
forced to be empty, even though there might be something we need to
COW.)

Fix all of it by limiting nb_clusters so the equivalent number of bytes
will not exceed INT_MAX.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Alberto Garcia f2208fdc5b block: Reject misaligned write requests with BDRV_REQ_NO_FALLBACK
The BDRV_REQ_NO_FALLBACK flag means that an operation should only be
performed if it can be offloaded or otherwise performed efficiently.

However a misaligned write request requires a RMW so we should return
an error and let the caller decide how to proceed.

This hits an assertion since commit c8bb23cbdb if the required
alignment is larger than the cluster size:

qemu-img create -f qcow2 -o cluster_size=2k img.qcow2 4G
qemu-io -c "open -o driver=qcow2,file.align=4k blkdebug::img.qcow2" \
        -c 'write 0 512'
qemu-io: block/io.c:1127: bdrv_driver_pwritev: Assertion `!(flags & BDRV_REQ_NO_FALLBACK)' failed.
Aborted

The reason is that when writing to an unallocated cluster we try to
skip the copy-on-write part and zeroize it using BDRV_REQ_NO_FALLBACK
instead, resulting in a write request that is too small (2KB cluster
size vs 4KB required alignment).

Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Pavel Dovgalyuk e4ec5ad464 replay: add BH oneshot event for block layer
Replay is capable of recording normal BH events, but sometimes
there are single use callbacks scheduled with aio_bh_schedule_oneshot
function. This patch enables recording and replaying such callbacks.
Block layer uses these events for calling the completion function.
Replaying these calls makes the execution deterministic.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Pavel Dovgalyuk c8aa7895eb replay: don't drain/flush bdrv queue while RR is working
In record/replay mode bdrv queue is controlled by replay mechanism.
It does not allow saving or loading the snapshots
when bdrv queue is not empty. Stopping the VM is not blocked by nonempty
queue, but flushing the queue is still impossible there,
because it may cause deadlocks in replay mode.
This patch disables bdrv_drain_all and bdrv_flush_all in
record/replay mode.

Stopping the machine when the IO requests are not finished is needed
for the debugging. E.g., breakpoint may be set at the specified step,
and forcing the IO requests to finish may break the determinism
of the execution.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Pavel Dovgalyuk 3c6c4348f2 block: implement bdrv_snapshot_goto for blkreplay
This patch enables making snapshots with blkreplay used in
block devices.
This function is required to make bdrv_snapshot_goto without
calling .bdrv_open which is not implemented.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Peter Lieven 6caaad46de block/vhdx: add check for truncated image files
qemu is currently not able to detect truncated vhdx image files.
Add a basic check if all allocated blocks are reachable at open and
report all errors during bdrv_co_check.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-10-14 17:12:48 +02:00
Maxim Levitsky e99754b42e nbd: add empty .bdrv_reopen_prepare
Fixes commit job / qemu-img commit, when
commiting qcow2 file which is based on nbd export.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1718727
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20190930213820.29777-2-mlevitsk@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Vladimir Sementsov-Ogievskiy 00e30f05de block/backup: use backup-top instead of write notifiers
Drop write notifiers and use filter node instead.

= Changes =

1. Add filter-node-name argument for backup qmp api. We have to do it
in this commit, as 257 needs to be fixed.

2. There are no more write notifiers here, so is_write_notifier
parameter is dropped from block-copy paths.

3. To sync with in-flight requests at job finish we now have drained
removing of the filter, we don't need rw-lock.

4. Block-copy is now using BdrvChildren instead of BlockBackends

5. As backup-top owns these children, we also move block-copy state
into backup-top's ownership.

= Iotest changes =

56: op-blocker doesn't shoot now, as we set it on source, but then
check on filter, when trying to start second backup.
To keep the test we instead can catch another collision: both jobs will
get 'drive0' job-id, as job-id parameter is unspecified. To prevent
interleaving with file-posix locks (as they are dependent on config)
let's use another target for second backup.

Also, it's obvious now that we'd like to drop this op-blocker at all
and add a test-case for two backups from one node (to different
destinations) actually works. But not in these series.

141: Output changed: prepatch, "Node is in use" comes from bdrv_has_blk
check inside qmp_blockdev_del. But we've dropped block-copy blk
objects, so no more blk objects on source bs (job blk is on backup-top
filter bs). New message is from op-blocker, which is the next check in
qmp_blockdev_add.

257: The test wants to emulate guest write during backup. They should
go to filter node, not to original source node, of course. Therefore we
need to specify filter node name and use it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-6-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Vladimir Sementsov-Ogievskiy 7df7868b96 block: introduce backup-top filter driver
Backup-top filter caches write operations and does copy-before-write
operations.

The driver will be used in backup instead of write-notifiers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-5-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Vladimir Sementsov-Ogievskiy 0f4b02b73e block/block-copy: split block_copy_set_callbacks function
Split block_copy_set_callbacks out of block_copy_state_new. It's needed
for further commit: block-copy will use BdrvChildren of backup-top
filter, so it will be created from backup-top filter creation function.
But callbacks will still belong to backup job and will be set in
separate.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-4-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Vladimir Sementsov-Ogievskiy 843670f30f block/backup: move write_flags calculation inside backup_job_create
This is logic-less refactoring, which simplifies further patch, as
we'll need write_flags for backup-top filter creation and backup-top
should be created before block job creation.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-3-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Vladimir Sementsov-Ogievskiy a6ffe1998c block/backup: move in-flight requests handling from backup to block-copy
Move synchronization mechanism to block-copy, to be able to use one
block-copy instance from backup job and backup-top filter in parallel.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-2-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Anton Nefedov d924559953 qapi: query-blockstat: add driver specific file-posix stats
A block driver can provide a callback to report driver-specific
statistics.

file-posix driver now reports discard statistics

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20190923121737.83281-10-anton.nefedov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Anton Nefedov 1c45036636 file-posix: account discard operations
This will help to identify how many of the user-issued discard operations
(accounted on a device level) have actually suceeded down on the host file
(even though the numbers will not be exactly the same if non-raw format
driver is used (e.g. qcow2 sending metadata discards)).

Note that these numbers will not include discards triggered by
write-zeroes + MAY_UNMAP calls.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190923121737.83281-9-anton.nefedov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Anton Nefedov f344446654 block: add empty account cookie type
Each block_acct_done/failed call is designed to correspond to a
previous block_acct_start call, which initializes the stats cookie.
However sometimes it is not the case, e.g. some error paths might
report the same cookie twice because it is hard to accurately track if
the cookie was reported yet or not.

This patch cleans the cookie after report.
(Note: block_acct_failed/done without a previous block_acct_start at
all should be avoided. Uninitialized cookie might hold a garbage value
and there is still "< BLOCK_MAX_IOTYPE" assertion for that)

It will be particularly useful in ide code where it's hard to
keep track whether the request done its accounting or not: in the
following patch of the series, trim requests will do the accounting
separately.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190923121737.83281-4-anton.nefedov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Anton Nefedov 159f85ddc8 qapi: add unmap to BlockDeviceStats
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20190923121737.83281-3-anton.nefedov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Vladimir Sementsov-Ogievskiy beb5f5450d block: move block_copy from block/backup.c to separate file
Split block_copy to separate file, to be cleanly shared with backup-top
filter driver in further commits.

It's a clean movement, the only change is drop "static" from interface
functions.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190920142056.12778-8-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 0e23e382b7 block/backup: fix block-comment style
We need to fix comment style around block-copy functions before further
moving them to separate file to satisfy checkpatch. But do more: fix
all comments style. Also, seems like doubled first asterisk is not
forbidden, but drop it too for consistency.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190920142056.12778-7-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 2c8074c453 block/backup: introduce BlockCopyState
Split copying code part from backup to "block-copy", including separate
state structure and function renaming. This is needed to share it with
backup-top filter driver in further commits.

Notes:

1. As BlockCopyState keeps own BlockBackend objects, remaining
job->common.blk users only use it to get bs by blk_bs() call, so clear
job->commen.blk permissions set in block_job_create and add
job->source_bs to be used instead of blk_bs(job->common.blk), to keep
it more clear which bs we use when introduce backup-top filter in
further commit.

2. Rename s/initializing_bitmap/skip_unallocated/ to sound a bit better
as interface to BlockCopyState

3. Split is not very clean: there left some duplicated fields, backup
code uses some BlockCopyState fields directly, let's postpone it for
further improvements and keep this comment simpler for review.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190920142056.12778-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 372c67ea61 block/backup: improve comment about image fleecing
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190920142056.12778-5-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 0bd0c44372 block/backup: split shareable copying part from backup_do_cow
Split copying logic which will be shared with backup-top filter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190920142056.12778-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 1048ddf0a3 block/backup: fix backup_cow_with_offload for last cluster
We shouldn't try to copy bytes beyond EOF. Fix it.

Fixes: 9ded4a0114
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190920142056.12778-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 981fb5810a block/backup: fix max_transfer handling for copy_range
Of course, QEMU_ALIGN_UP is a typo, it should be QEMU_ALIGN_DOWN, as we
are trying to find aligned size which satisfy both source and target.
Also, don't ignore too small max_transfer. In this case seems safer to
disable copy_range.

Fixes: 9ded4a0114
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190920142056.12778-2-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy d710cf575a block/qcow2: introduce parallel subrequest handling in read and write
It improves performance for fragmented qcow2 images.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190916175324.18478-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 6aa7a2631b block/qcow2: refactor qcow2_co_pwritev_part
Similarly to previous commit, prepare for parallelizing write-loop
iterations.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190916175324.18478-5-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 88f468e546 block/qcow2: refactor qcow2_co_preadv_part
Further patch will run partial requests of iterations of
qcow2_co_preadv in parallel for performance reasons. To prepare for
this, separate part which may be parallelized into separate function
(qcow2_co_preadv_task).

While being here, also separate encrypted clusters reading to own
function, like it is done for compressed reading.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190916175324.18478-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Vladimir Sementsov-Ogievskiy 6e9b225f73 block: introduce aio task pool
Common interface for aio task loops. To be used for improving
performance of synchronous io loops in qcow2, block-stream,
copy-on-read, and may be other places.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190916175324.18478-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:17 +02:00
Max Reitz 8644476e51 block: Skip COR for inactive nodes
We must not write data to inactive nodes, and a COR is certainly
something we can simply not do without upsetting anyone.  So skip COR
operations on inactive nodes.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191001174827.11081-2-mreitz@redhat.com
Message-Id: <20191001174827.11081-2-mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-10-08 14:28:25 +01:00
Kevin Wolf 05f4aced65 block/snapshot: Restrict set of snapshot nodes
Nodes involved in internal snapshots were those that were returned by
bdrv_next(), inserted and not read-only. bdrv_next() in turn returns all
nodes that are either the root node of a BlockBackend or monitor-owned
nodes.

With the typical -drive use, this worked well enough. However, in the
typical -blockdev case, the user defines one node per option, making all
nodes monitor-owned nodes. This includes protocol nodes etc. which often
are not snapshottable, so "savevm" only returns an error.

Change the conditions so that internal snapshot still include all nodes
that have a BlockBackend attached (we definitely want to snapshot
anything attached to a guest device and probably also the built-in NBD
server; snapshotting block job BlockBackends is more of an accident, but
a preexisting one), but other monitor-owned nodes are only included if
they have no parents.

This makes internal snapshots usable again with typical -blockdev
configurations.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
2019-10-04 11:52:40 +02:00
Philippe Mathieu-Daudé 31e404151b cutils: Move size_to_str() from "qemu-common.h" to "qemu/cutils.h"
"qemu/cutils.h" contains various qemu_strtosz_*() functions
useful to convert strings to size. It seems natural to have
the opposite usage (from size to string) there too.

The function definition is already in util/cutils.c.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20190903120555.7551-1-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-09-19 11:57:34 +02:00
Maxim Levitsky 603fbd076c block/qcow2: refactor encryption code
* Change the qcow2_co_{encrypt|decrypt} to just receive full host and
  guest offsets and use this function directly instead of calling
  do_perform_cow_encrypt (which is removed by that patch).

* Adjust qcow2_co_encdec to take full host and guest offsets as well.

* Document the qcow2_co_{encrypt|decrypt} arguments
  to prevent the bug fixed in former commit from hopefully
  happening again.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20190915203655.21638-3-mlevitsk@redhat.com
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[mreitz: Let perform_cow() return the error value returned by
         qcow2_co_encrypt(), as proposed by Vladimir]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:36:22 +02:00
Maxim Levitsky 38e7d54bdc block/qcow2: Fix corruption introduced by commit 8ac0f15f33
This fixes subtle corruption introduced by luks threaded encryption
in commit 8ac0f15f33

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1745922

The corruption happens when we do a write that
   * writes to two or more unallocated clusters at once
   * doesn't fully cover the first sector
   * doesn't fully cover the last sector
   * uses luks encryption

In this case, when allocating the new clusters we COW both areas
prior to the write and after the write, and we encrypt them.

The above mentioned commit accidentally made it so we encrypt the
second COW area using the physical cluster offset of the first area.

The problem is that offset_in_cluster in do_perform_cow_encrypt
can be larger that the cluster size, thus cluster_offset
will no longer point to the start of the cluster at which encrypted
area starts.

Next patch in this series will refactor the code to avoid all these
assumptions.

In the bugreport that was triggered by rebasing a luks image to new,
zero filled base, which lot of such writes, and causes some files
with zero areas to contain garbage there instead.
But as described above it can happen elsewhere as well

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190915203655.21638-2-mlevitsk@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:35:02 +02:00
Max Reitz c34dc07f9f curl: Check curl_multi_add_handle()'s return code
If we had done that all along, debugging would have been much simpler.
(Also, I/O errors are better than hangs.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190910124136.10565-8-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:12 +02:00
Max Reitz bfb23b480a curl: Handle success in multi_check_completion
Background: As of cURL 7.59.0, it verifies that several functions are
not called from within a callback.  Among these functions is
curl_multi_add_handle().

curl_read_cb() is a callback from cURL and not a coroutine.  Waking up
acb->co will lead to entering it then and there, which means the current
request will settle and the caller (if it runs in the same coroutine)
may then issue the next request.  In such a case, we will enter
curl_setup_preadv() effectively from within curl_read_cb().

Calling curl_multi_add_handle() will then fail and the new request will
not be processed.

Fix this by not letting curl_read_cb() wake up acb->co.  Instead, leave
the whole business of settling the AIOCB objects to
curl_multi_check_completion() (which is called from our timer callback
and our FD handler, so not from any cURL callbacks).

Reported-by: Natalie Gavrielov <ngavrilo@redhat.com>
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1740193
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190910124136.10565-7-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:11 +02:00
Max Reitz 9abaf9fc47 curl: Report only ready sockets
Instead of reporting all sockets to cURL, only report the one that has
caused curl_multi_do_locked() to be called.  This lets us get rid of the
QLIST_FOREACH_SAFE() list, which was actually wrong: SAFE foreaches are
only safe when the current element is removed in each iteration.  If it
possible for the list to be concurrently modified, we cannot guarantee
that only the current element will be removed.  Therefore, we must not
use QLIST_FOREACH_SAFE() here.

Fixes: ff5ca1664a
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190910124136.10565-6-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:11 +02:00
Max Reitz 9dbad87d25 curl: Pass CURLSocket to curl_multi_do()
curl_multi_do_locked() currently marks all sockets as ready.  That is
not only inefficient, but in fact unsafe (the loop is).  A follow-up
patch will change that, but to do so, curl_multi_do_locked() needs to
know exactly which socket is ready; and that is accomplished by this
patch here.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190910124136.10565-5-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:11 +02:00
Max Reitz 948403bcb1 curl: Check completion in curl_multi_do()
While it is more likely that transfers complete after some file
descriptor has data ready to read, we probably should not rely on it.
Better be safe than sorry and call curl_multi_check_completion() in
curl_multi_do(), too, just like it is done in curl_multi_read().

With this change, curl_multi_do() and curl_multi_read() are actually the
same, so drop curl_multi_read() and use curl_multi_do() as the sole FD
handler.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190910124136.10565-4-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:11 +02:00
Max Reitz 007f339b10 curl: Keep *socket until the end of curl_sock_cb()
This does not really change anything, but it makes the code a bit easier
to follow once we use @socket as the opaque pointer for
aio_set_fd_handler().

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190910124136.10565-3-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:11 +02:00
Max Reitz 0487861685 curl: Keep pointer to the CURLState in CURLSocket
A follow-up patch will make curl_multi_do() and curl_multi_read() take a
CURLSocket instead of the CURLState.  They still need the latter,
though, so add a pointer to it to the former.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190910124136.10565-2-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 15:31:11 +02:00
Nir Soffer 1bbbf32d5f block: Use QEMU_IS_ALIGNED
Replace instances of:

    (n & (BDRV_SECTOR_SIZE - 1)) == 0

And:

   (n & ~BDRV_SECTOR_MASK) == 0

With:

    QEMU_IS_ALIGNED(n, BDRV_SECTOR_SIZE)

Which reveals the intent of the code better, and makes it easier to
locate the code checking alignment.

Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Message-id: 20190827185913.27427-2-nsoffer@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-16 14:48:30 +02:00
Alberto Garcia bf3d78ae55 qcow2: Stop overwriting compressed clusters one by one
handle_alloc() tries to find as many contiguous clusters that need
copy-on-write as possible in order to allocate all of them at the same
time.

However, compressed clusters are only overwritten one by one, so let's
say that we have an image with 1024 consecutive compressed clusters:

   qemu-img create -f qcow2 hd.qcow2 64M
   for f in `seq 0 64 65472`; do
      qemu-io -c "write -c ${f}k 64k" hd.qcow2
   done

In this case trying to overwrite the whole image with one large write
request results in 1024 separate allocations:

   qemu-io -c "write 0 64M" hd.qcow2

This restriction comes from commit 095a9c58ce from 2008.
Nowadays QEMU can overwrite multiple compressed clusters just fine,
and in fact it already does: as long as the first cluster that
handle_alloc() finds is not compressed, all other compressed clusters
in the same batch will be overwritten in one go:

   qemu-img create -f qcow2 hd.qcow2 64M
   qemu-io -c "write -z 0 64k" hd.qcow2
   for f in `seq 64 64 65472`; do
      qemu-io -c "write -c ${f}k 64k" hd.qcow2
   done

Compared to the previous one, overwriting this image on my computer
goes from 8.35s down to 230ms.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: John Snow <jsnow@redhat.com
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-13 12:18:37 +02:00
Philippe Mathieu-Daudé d90d5cae2b block/create: Do not abort if a block driver is not available
The 'blockdev-create' QMP command was introduced as experimental
feature in commit b0292b851b, using the assert() debug call.
It got promoted to 'stable' command in 3fb588a0f2, but the
assert call was not removed.

Some block drivers are optional, and bdrv_find_format() might
return a NULL value, triggering the assertion.

Stable code is not expected to abort, so return an error instead.

This is easily reproducible when libnfs is not installed:

  ./configure
  [...]
  module support    no
  Block whitelist (rw)
  Block whitelist (ro)
  libiscsi support  yes
  libnfs support    no
  [...]

Start QEMU:

  $ qemu-system-x86_64 -S -qmp unix:/tmp/qemu.qmp,server,nowait

Send the 'blockdev-create' with the 'nfs' driver:

  $ ( cat << 'EOF'
  {'execute': 'qmp_capabilities'}
  {'execute': 'blockdev-create', 'arguments': {'job-id': 'x', 'options': {'size': 0, 'driver': 'nfs', 'location': {'path': '/', 'server': {'host': '::1', 'type': 'inet'}}}}, 'id': 'x'}
  EOF
  ) | socat STDIO UNIX:/tmp/qemu.qmp
  {"QMP": {"version": {"qemu": {"micro": 50, "minor": 1, "major": 4}, "package": "v4.1.0-733-g89ea03a7dc"}, "capabilities": ["oob"]}}
  {"return": {}}

QEMU crashes:

  $ gdb qemu-system-x86_64 core
  Program received signal SIGSEGV, Segmentation fault.
  (gdb) bt
  #0  0x00007ffff510957f in raise () at /lib64/libc.so.6
  #1  0x00007ffff50f3895 in abort () at /lib64/libc.so.6
  #2  0x00007ffff50f3769 in _nl_load_domain.cold.0 () at /lib64/libc.so.6
  #3  0x00007ffff5101a26 in .annobin_assert.c_end () at /lib64/libc.so.6
  #4  0x0000555555d7e1f1 in qmp_blockdev_create (job_id=0x555556baee40 "x", options=0x555557666610, errp=0x7fffffffc770) at block/create.c:69
  #5  0x0000555555c96b52 in qmp_marshal_blockdev_create (args=0x7fffdc003830, ret=0x7fffffffc7f8, errp=0x7fffffffc7f0) at qapi/qapi-commands-block-core.c:1314
  #6  0x0000555555deb0a0 in do_qmp_dispatch (cmds=0x55555645de70 <qmp_commands>, request=0x7fffdc005c70, allow_oob=false, errp=0x7fffffffc898) at qapi/qmp-dispatch.c:131
  #7  0x0000555555deb2a1 in qmp_dispatch (cmds=0x55555645de70 <qmp_commands>, request=0x7fffdc005c70, allow_oob=false) at qapi/qmp-dispatch.c:174

With this patch applied, QEMU returns a QMP error:

  {'execute': 'blockdev-create', 'arguments': {'job-id': 'x', 'options': {'size': 0, 'driver': 'nfs', 'location': {'path': '/', 'server': {'host': '::1', 'type': 'inet'}}}}, 'id': 'x'}
  {"id": "x", "error": {"class": "GenericError", "desc": "Block driver 'nfs' not found or not supported"}}

Cc: qemu-stable@nongnu.org
Reported-by: Xu Tian <xutian@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-13 12:18:37 +02:00
Peter Lieven d2c6becbe0 block/nfs: add support for nfs_umount
libnfs recently added support for unmounting. Add support
in Qemu too.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-13 12:18:15 +02:00
Peter Lieven 601dc65597 block/nfs: tear down aio before nfs_close
nfs_close is a sync call from libnfs and has its own event
handler polling on the nfs FD. Avoid that both QEMU and libnfs
are intefering here.

CC: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-13 12:18:14 +02:00
Max Reitz 1a37e31244 vpc: Return 0 from vpc_co_create() on success
blockdev_create_run() directly uses .bdrv_co_create()'s return value as
the job's return value.  Jobs must return 0 on success, not just any
nonnegative value.  Therefore, using blockdev-create for VPC images may
currently fail as the vpc driver may return a positive integer.

Because there is no point in returning a positive integer anywhere in
the block layer (all non-negative integers are generally treated as
complete success), we probably do not want to add more such cases.
Therefore, fix this problem by making the vpc driver always return 0 in
case of success.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-10 08:58:43 +02:00
Kevin Wolf effecce6bc file-posix: Fix has_write_zeroes after NO_FALLBACK
If QEMU_AIO_NO_FALLBACK is given, we always return failure and don't
even try to use the BLKZEROOUT ioctl. In this failure case, we shouldn't
disable has_write_zeroes because we didn't learn anything about the
ioctl. The next request might not set QEMU_AIO_NO_FALLBACK and we can
still use the ioctl then.

Fixes: 738301e117
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2019-09-10 08:58:43 +02:00
Max Reitz b2c6f23f4a block/file-posix: Reduce xfsctl() use
This patch removes xfs_write_zeroes() and xfs_discard().  Both functions
have been added just before the same feature was present through
fallocate():

- fallocate() has supported PUNCH_HOLE for XFS since Linux 2.6.38 (March
  2011); xfs_discard() was added in December 2010.

- fallocate() has supported ZERO_RANGE for XFS since Linux 3.15 (June
  2014); xfs_write_zeroes() was added in November 2013.

Nowadays, all systems that qemu runs on should support both fallocate()
features (RHEL 7's kernel does).

xfsctl() is still useful for getting the request alignment for O_DIRECT,
so this patch does not remove our dependency on it completely.

Note that xfs_write_zeroes() had a bug: It calls ftruncate() when the
file is shorter than the specified range (because ZERO_RANGE does not
increase the file length).  ftruncate() may yield and then discard data
that parallel write requests have written past the EOF in the meantime.
Dropping the function altogether fixes the bug.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: 50ba5b2d99
Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Tested-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-10 08:58:43 +02:00
Vladimir Sementsov-Ogievskiy bb0c940993 job: drop job_drain
In job_finish_sync job_enter should be enough for a job to make some
progress and draining is a wrong tool for it. So use job_enter directly
here and drop job_drain with all related staff not used more.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Tested-by: John Snow <jsnow@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-10 08:58:43 +02:00
Alberto Garcia b70d08205b qcow2: Fix the calculation of the maximum L2 cache size
The size of the qcow2 L2 cache defaults to 32 MB, which can be easily
larger than the maximum amount of L2 metadata that the image can have.
For example: with 64 KB clusters the user would need a qcow2 image
with a virtual size of 256 GB in order to have 32 MB of L2 metadata.

Because of that, since commit b749562d98
we forbid the L2 cache to become larger than the maximum amount of L2
metadata for the image, calculated using this formula:

    uint64_t max_l2_cache = virtual_disk_size / (s->cluster_size / 8);

The problem with this formula is that the result should be rounded up
to the cluster size because an L2 table on disk always takes one full
cluster.

For example, a 1280 MB qcow2 image with 64 KB clusters needs exactly
160 KB of L2 metadata, but we need 192 KB on disk (3 clusters) even if
the last 32 KB of those are not going to be used.

However QEMU rounds the numbers down and only creates 2 cache tables
(128 KB), which is not enough for the image.

A quick test doing 4KB random writes on a 1280 MB image gives me
around 500 IOPS, while with the correct cache size I get 16K IOPS.

Cc: qemu-stable@nongnu.org
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-09-10 08:58:43 +02:00
Eric Blake f061656cc3 nbd: Implement client use of NBD FAST_ZERO
The client side is fairly straightforward: if the server advertised
fast zero support, then we can map that to BDRV_REQ_NO_FALLBACK
support.  A server that advertises FAST_ZERO but not WRITE_ZEROES
is technically broken, but we can ignore that situation as it does
not change our behavior.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190823143726.27062-4-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2019-09-05 16:03:26 -05:00
Andrey Shinkevich 294682cc3a block: workaround for unaligned byte range in fallocate()
Revert the commit 118f99442d 'block/io.c: fix for the allocation failure'
and use better error handling for file systems that do not support
fallocate() for an unaligned byte range. Allow falling back to pwrite
in case fallocate() returns EINVAL.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <1566913973-15490-1-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-09-05 16:01:31 -05:00
Eric Blake df18c04edf nbd: Use g_autofree in a few places
Thanks to our recent move to use glib's g_autofree, I can join the
bandwagon.  Getting rid of gotos is fun ;)

There are probably more places where we could register cleanup
functions and get rid of more gotos; this patch just focuses on the
labels that existed merely to call g_free.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190824172813.29720-2-eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2019-09-05 15:52:45 -05:00
Stefan Hajnoczi 236094c738 file-posix: fix request_alignment typo
Fixes: a6b257a08e
       ("file-posix: Handle undetectable alignment")
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190827101328.4062-1-stefanha@redhat.com
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-03 14:55:35 +02:00
Max Reitz bedb8bb419 vmdk: Reject invalid compressed writes
Compressed writes generally have to write full clusters, not just in
theory but also in practice when it comes to vmdk's streamOptimized
subformat.  It currently is just silently broken for writes with
non-zero in-cluster offsets:

$ qemu-img create -f vmdk -o subformat=streamOptimized foo.vmdk 1M
$ qemu-io -c 'write 4k 4k' -c 'read 4k 4k' foo.vmdk
wrote 4096/4096 bytes at offset 4096
4 KiB, 1 ops; 00.01 sec (443.724 KiB/sec and 110.9309 ops/sec)
read failed: Invalid argument

(The technical reason is that vmdk_write_extent() just writes the
incomplete compressed data actually to offset 4k.  When reading the
data, vmdk_read_extent() looks at offset 0 and finds the compressed data
size to be 0, because that is what it reads from there.  This yields an
error.)

For incomplete writes with zero in-cluster offsets, the error path when
reading the rest of the cluster is a bit different, but the result is
the same:

$ qemu-img create -f vmdk -o subformat=streamOptimized foo.vmdk 1M
$ qemu-io -c 'write 0k 4k' -c 'read 4k 4k' foo.vmdk
wrote 4096/4096 bytes at offset 0
4 KiB, 1 ops; 00.01 sec (362.641 KiB/sec and 90.6603 ops/sec)
read failed: Invalid argument

(Here, vmdk_read_extent() finds the data and then sees that the
uncompressed data is short.)

It is better to reject invalid writes than to make the user believe they
might have succeeded and then fail when trying to read it back.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190815153638.4600-5-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-03 14:55:35 +02:00
Max Reitz cdc0dd2586 vmdk: Use bdrv_dirname() for relative extent paths
This makes iotest 033 pass with e.g. subformat=monolithicFlat.  It also
turns a former error in 059 into success.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190815153638.4600-3-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-03 14:55:35 +02:00
Nir Soffer 3a20013fbb block: posix: Always allocate the first block
When creating an image with preallocation "off" or "falloc", the first
block of the image is typically not allocated. When using Gluster
storage backed by XFS filesystem, reading this block using direct I/O
succeeds regardless of request length, fooling alignment detection.

In this case we fallback to a safe value (4096) instead of the optimal
value (512), which may lead to unneeded data copying when aligning
requests.  Allocating the first block avoids the fallback.

Since we allocate the first block even with preallocation=off, we no
longer create images with zero disk size:

    $ ./qemu-img create -f raw test.raw 1g
    Formatting 'test.raw', fmt=raw size=1073741824

    $ ls -lhs test.raw
    4.0K -rw-r--r--. 1 nsoffer nsoffer 1.0G Aug 16 23:48 test.raw

And converting the image requires additional cluster:

    $ ./qemu-img measure -f raw -O qcow2 test.raw
    required size: 458752
    fully allocated size: 1074135040

When using format like vmdk with multiple files per image, we allocate
one block per file:

    $ ./qemu-img create -f vmdk -o subformat=twoGbMaxExtentFlat test.vmdk 4g
    Formatting 'test.vmdk', fmt=vmdk size=4294967296 compat6=off hwversion=undefined subformat=twoGbMaxExtentFlat

    $ ls -lhs test*.vmdk
    4.0K -rw-r--r--. 1 nsoffer nsoffer 2.0G Aug 27 03:23 test-f001.vmdk
    4.0K -rw-r--r--. 1 nsoffer nsoffer 2.0G Aug 27 03:23 test-f002.vmdk
    4.0K -rw-r--r--. 1 nsoffer nsoffer  353 Aug 27 03:23 test.vmdk

I did quick performance test for copying disks with qemu-img convert to
new raw target image to Gluster storage with sector size of 512 bytes:

    for i in $(seq 10); do
        rm -f dst.raw
        sleep 10
        time ./qemu-img convert -f raw -O raw -t none -T none src.raw dst.raw
    done

Here is a table comparing the total time spent:

Type    Before(s)   After(s)    Diff(%)
---------------------------------------
real      530.028    469.123      -11.4
user       17.204     10.768      -37.4
sys        17.881      7.011      -60.7

We can see very clear improvement in CPU usage.

Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Message-id: 20190827010528.8818-2-nsoffer@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-09-03 14:55:35 +02:00
Vladimir Sementsov-Ogievskiy 5396234b96 block/qcow2: implement .bdrv_co_pwritev(_compressed)_part
Implement and use new interface to get rid of hd_qiov.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-13-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-13-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy df893d25ce block/qcow2: implement .bdrv_co_preadv_part
Implement and use new interface to get rid of hd_qiov.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-12-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-12-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 00721a3529 block/qcow2: refactor qcow2_co_preadv to use buffer-based io
Use buffer based io in encrypted case.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-11-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-11-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 1acc3466a2 block/io: introduce bdrv_co_p{read, write}v_part
Introduce extended variants of bdrv_co_preadv and bdrv_co_pwritev
with qiov_offset parameter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-10-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-10-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 28c4da2869 block/io: bdrv_aligned_pwritev: use and support qiov_offset
Use and support new API in bdrv_aligned_pwritev.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-9-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-9-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 65cd4424b9 block/io: bdrv_aligned_preadv: use and support qiov_offset
Use and support new API in bdrv_co_do_copy_on_readv.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-8-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-8-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 2275cc90a1 block/io: bdrv_co_do_copy_on_readv: lazy allocation
Allocate bounce_buffer only if it is really needed. Also, sub-optimize
allocation size (why not?).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-7-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-7-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 1143ec5ebf block/io: bdrv_co_do_copy_on_readv: use and support qiov_offset
Use and support new API in bdrv_co_do_copy_on_readv. Note that in case
of allocated-in-top we need to shrink read size to MIN(..) by hand, as
pre-patch this was actually done implicitly by qemu_iovec_concat (and
we used local_qiov.size).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-6-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-6-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy ac850bf099 block: define .*_part io handlers in BlockDriver
Add handlers supporting qiov_offset parameter:
    bdrv_co_preadv_part
    bdrv_co_pwritev_part
    bdrv_co_pwritev_compressed_part
This is used to reduce need of defining local_qiovs and hd_qiovs in all
corners of block layer code. The following patches will increase usage
of this new API part by part.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-5-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-5-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:42 +01:00
Vladimir Sementsov-Ogievskiy 7a3f542fbd block/io: refactor padding
We have similar padding code in bdrv_co_pwritev,
bdrv_co_do_pwrite_zeroes and bdrv_co_preadv. Let's combine and unify
it.

[Squashed in Vladimir's qemu-iotests 077 fix
--Stefan]

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-4-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-4-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:58:12 +01:00
Vladimir Sementsov-Ogievskiy f76889e7b9 util/iov: improve qemu_iovec_is_zero
We'll need to check a part of qiov soon, so implement it now.

Optimization with align down to 4 * sizeof(long) is dropped due to:
1. It is strange: it aligns length of the buffer, but where is a
   guarantee that buffer pointer is aligned itself?
2. buffer_is_zero() is a better place for optimizations and it has
   them.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-3-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-3-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-08-27 14:52:45 +01:00
Max Reitz fbc8e1b7e4 vpc: Do not return RAW from block_status
vpc is not really a passthrough driver, even when using the fixed
subformat (where host and guest offsets are equal).  It should handle
preallocation like all other drivers do, namely by returning
DATA | RECURSE instead of RAW.

There is no tangible difference but the fact that bdrv_is_allocated() no
longer falls through to the protocol layer.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190725155512.9827-4-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz 4dd84ac9a7 vmdk: Make block_status recurse for flat extents
Fixes: 69f47505ee
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190725155512.9827-3-mreitz@redhat.com
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz ad6434dc62 vdi: Make block_status recurse for fixed images
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Fixes: 69f47505ee
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190725155512.9827-2-mreitz@redhat.com
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz 9956688a8f vhdx: Fix .bdrv_has_zero_init()
Fixed VHDX images cannot guarantee to be zero-initialized.  If the image
has the "fixed" subformat, forward the call to the underlying storage
node.

Reported-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-9-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz 0a28bf2826 vdi: Fix .bdrv_has_zero_init()
Static VDI images cannot guarantee to be zero-initialized.  If the image
has been statically allocated, forward the call to the underlying
storage node.

Reported-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20190724171239.8764-8-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz 38841dcd27 qcow2: Fix .bdrv_has_zero_init()
If a qcow2 file is preallocated, it can no longer guarantee that it
initially appears as filled with zeroes.

So implement .bdrv_has_zero_init() by checking whether the file is
preallocated; if so, forward the call to the underlying storage node,
except for when it is encrypted: Encrypted preallocated images always
return effectively random data, so .bdrv_has_zero_init() must always
return 0 for them.

.bdrv_has_zero_init_truncate() can remain bdrv_has_zero_init_1(),
because it presupposes PREALLOC_MODE_OFF.

Reported-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-7-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz b647d69adc block: Use bdrv_has_zero_init_truncate()
vhdx and parallels call bdrv_has_zero_init() when they do not really
care about an image's post-create state but only about what happens when
you grow an image.  That is a bit ugly, and also overly safe when
growing preallocated images without preallocating the new areas.

Let them use bdrv_has_zero_init_truncate() instead.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-6-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
[mreitz: Added commit message]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz 1dcaf52760 block: Implement .bdrv_has_zero_init_truncate()
We need to implement .bdrv_has_zero_init_truncate() for every block
driver that supports truncation and has a .bdrv_has_zero_init()
implementation.

Implement it the same way each driver implements .bdrv_has_zero_init().
This is at least not any more unsafe than what we had before.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-5-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Max Reitz cdf3bc934a mirror: Fix bdrv_has_zero_init() use
bdrv_has_zero_init() only has meaning for newly created images or image
areas.  If the mirror job itself did not create the image, it cannot
rely on bdrv_has_zero_init()'s result to carry any meaning.

This is the case for drive-mirror with mode=existing and always for
blockdev-mirror.

Note that we only have to zero-initialize the target with sync=full,
because other modes actually do not promise that the target will contain
the same data as the source after the job -- sync=top only promises to
copy anything allocated in the top layer, and sync=none will only copy
new I/O.  (Which is how mirror has always handled it.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-3-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Maxim Levitsky 672de729a1 LUKS: support preallocation
preallocation=off and preallocation=metadata
both allocate luks header only, and preallocation=falloc/full
is passed to underlying file.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1534951

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20190716161901.1430-1-mlevitsk@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Peter Maydell 3fbd3405d2 - Run the iotest during "make check"
-----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCAAvFiEEJ7iIR+7gJQEY8+q5LtnXdP5wLbUFAl1XvtURHHRodXRoQHJl
 ZGhhdC5jb20ACgkQLtnXdP5wLbUqqRAAqfjPRPtXSZxaxl63O5EADugLY72s+04i
 Zc5MC4Ivwj0x1WA6JIG77kz6xmjIOizRIkF1jkyEkG+AgIrjw3rdYhCD4Iav0n/v
 nqltkOaf1FzdQYCHUTn0WUYn7Df2bSkjSTPhnqbCaGq5WjXzgzi9jhCFlZpo374J
 9yWk74nt3QlOUjLw6+cm0HxEf9IlRQdPwJNYJwsrYHgspJwcwAYJ7xaL34huoxkJ
 10fA9q6QK1bh67nZpAJOte3wQ8r35cUT4ZaIiyO0MFMrEiLp4/1gKYpkZwWq0+iV
 25rWVjogzRjp+LejMAltY9MmUekCl5ZzVVuhdt2jGPbNanzdHxHydYFUELP6WmrM
 zAyYQkDvG7JiY2F0M9rKJZOnpO2pYF2hxc/nqD04qF3HD0zG1eoIg056UlKcc5b/
 kIgR2srlj0aHWhGJ2/DV3w5ZowjJGKBAYYxQdEJmiuLpGdOimSoWXbjacDEd4mUf
 DevXv6k9cAvexZxU4cOUzpip4U3MGC0rJ1BNIgTs6eIeKq3geROTpuHjJFSBHZiP
 H/MqtoT4xTXJYomc9MiZG90fG9KyywlEF6e0GjVIcadJEmFIbJ+DfrAknVRjuaij
 ThMSIuvMEpXFhyghlApURePNi8W3FIIYHISw0JE/u7+4/7L/iYDToYeM/o563+8O
 zbj0n9fSewI=
 =oVZx
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/huth-gitlab/tags/pull-request-2019-08-17' into staging

- Run the iotest during "make check"

# gpg: Signature made Sat 17 Aug 2019 09:46:13 BST
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* remotes/huth-gitlab/tags/pull-request-2019-08-17:
  gitlab-ci: Remove qcow2 tests that are handled by "make check" already
  tests: Run the iotests during "make check" again
  block: fix NetBSD qemu-iotests failure

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-08-19 14:14:09 +01:00
Paolo Bonzini f6fc1e30cf block: fix NetBSD qemu-iotests failure
Opening a block device on NetBSD has an additional step compared to other OSes,
corresponding to raw_normalize_devicepath.  The error message in that function
is slightly different from that in raw_open_common and this was causing spurious
failures in qemu-iotests.  However, in general it is not important to know what
exact step was failing, for example in the qemu-iotests case the error message
contains the fairly unequivocal "No such file or directory" text from strerror.
We can thus fix the failures by standardizing on a single error message for
both raw_open_common and raw_normalize_devicepath; in fact, we can even
use error_setg_file_open to make sure the error message is the same as in
the rest of QEMU.

Message-Id: <20190725095920.28419-1-pbonzini@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2019-08-17 09:02:59 +02:00
Vladimir Sementsov-Ogievskiy a1ed82b443 block/backup: refactor write_flags
write flags are constant, let's store it in BackupBlockJob instead of
recalculating. It also makes two boolean fields to be unused, so,
drop them.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190730163251.755248-4-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 18:29:43 -04:00
Vladimir Sementsov-Ogievskiy 319bd5edb9 block/backup: deal with zero detection
We have detect_zeroes option, so at least for blockdev-backup user
should define it if zero-detection is needed. For drive-backup leave
detection enabled by default but do it through existing option instead
of open-coding.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190730163251.755248-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 18:29:43 -04:00
Vladimir Sementsov-Ogievskiy 590a63d598 qapi: add dirty-bitmaps to query-named-block-nodes result
Let's add a possibility to query dirty-bitmaps not only on root nodes.
It is useful when dealing both with snapshots and incremental backups.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20190717173937.18747-1-jsnow@redhat.com
[Added deprecation information. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
[Fixed spelling --js]
2019-08-16 18:29:43 -04:00
John Snow 1a2b8b406b block/backup: support bitmap sync modes for non-bitmap backups
Accept bitmaps and sync policies for the other backup modes.
This allows us to do things like create a bitmap synced to a full backup
without a transaction, or start a resumable backup process.

Some combinations don't make sense, though:

- NEVER policy combined with any non-BITMAP mode doesn't do anything,
  because the bitmap isn't used for input or output.
  It's harmless, but is almost certainly never what the user wanted.

- sync=NONE is more questionable. It can't use on-success because this
  job never completes with success anyway, and the resulting artifact
  of 'always' is suspect: because we start with a full bitmap and only
  copy out segments that get written to, the final output bitmap will
  always be ... a fully set bitmap.

  Maybe there's contexts in which bitmaps make sense for sync=none,
  but not without more severe changes to the current job, and omitting
  it here doesn't prevent us from adding it later.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-11-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 18:29:43 -04:00
John Snow 7e30dd618e block/backup: teach TOP to never copy unallocated regions
Presently, If sync=TOP is selected, we mark the entire bitmap as dirty.
In the write notifier handler, we dutifully copy out such regions.

Fix this in three parts:

1. Mark the bitmap as being initialized before the first yield.
2. After the first yield but before the backup loop, interrogate the
allocation status asynchronously and initialize the bitmap.
3. Teach the write notifier to interrogate allocation status if it is
invoked during bitmap initialization.

As an effect of this patch, the job progress for TOP backups
now behaves like this:

- total progress starts at bdrv_length.
- As allocation status is interrogated, total progress decreases.
- As blocks are copied, current progress increases.

Taken together, the floor and ceiling move to meet each other.


Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20190716000117.25219-10-jsnow@redhat.com
[Remove ret = -ECANCELED change. --js]
[Squash in conflict resolution based on Max's patch --js]
Message-id: c8b0ab36-79c8-0b4b-3193-4e12ed8c848b@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow dba8700f16 block/backup: add backup_is_cluster_allocated
Modify bdrv_is_unallocated_range to utilize the pnum return from
bdrv_is_allocated, and in the process change the semantics from
"is unallocated" to "is allocated."

Optionally returns a full number of clusters that share the same
allocation status.

This will be used to carefully toggle bits in the bitmap for sync=top
initialization in the following commits.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-9-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow 141cdcdf84 block/backup: centralize copy_bitmap initialization
Just a few housekeeping changes that keeps the following commit easier
to read; perform the initial copy_bitmap initialization in one place.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow 0fff1f1371 block/backup: improve sync=bitmap work estimates
When making backups based on bitmaps, the work estimate can be more
accurate. Update iotests to reflect the new strategy.

TOP work estimates are broken, but do not get worse with this commit.
That issue is addressed in the following commits instead.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow a6c9365ad4 block/backup: hoist bitmap check into QMP interface
This is nicer to do in the unified QMP interface that we have now,
because it lets us use the right terminology back at the user.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow c4e4b0fa59 qapi: implement block-dirty-bitmap-remove transaction action
It is used to do transactional movement of the bitmap (which is
possible in conjunction with merge command). Transactional bitmap
movement is needed in scenarios with external snapshot, when we don't
want to leave copy of the bitmap in the base image.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190708220502.12977-3-jsnow@redhat.com
[Edited "since" version to 4.2 --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow b30ffbef53 block/backup: loosen restriction on readonly bitmaps
With the "never" sync policy, we actually can utilize readonly bitmaps
now. Loosen the check at the QMP level, and tighten it based on
provided arguments down at the job creation level instead.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-19-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow c23909e530 block/backup: add 'always' bitmap sync policy
This adds an "always" policy for bitmap synchronization. Regardless of if
the job succeeds or fails, the bitmap is *always* synchronized. This means
that for backups that fail part-way through, the bitmap retains a record of
which sectors need to be copied out to accomplish a new backup using the
old, partial result.

In effect, this allows us to "resume" a failed backup; however the new backup
will be from the new point in time, so it isn't a "resume" as much as it is
an "incremental retry." This can be useful in the case of extremely large
backups that fail considerably through the operation and we'd like to not waste
the work that was already performed.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-13-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow 62aa1fbeac block/backup: upgrade copy_bitmap to BdrvDirtyBitmap
This simplifies some interface matters; namely the initialization and
(later) merging the manifest back into the sync_bitmap if it was
provided.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-12-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow 28636b8211 block/dirty-bitmap: add bdrv_dirty_bitmap_get
Add a public interface for get. While we're at it,
rename "bdrv_get_dirty_bitmap_locked" to "bdrv_dirty_bitmap_get_locked".

(There are more functions to rename to the bdrv_dirty_bitmap_VERB form,
but they will wait until the conclusion of this series.)

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-11-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow b7661ca5d8 block/dirty-bitmap: add bdrv_dirty_bitmap_merge_internal
I'm surprised it didn't come up sooner, but sometimes we have a +busy
bitmap as a source. This is dangerous from the QMP API, but if we are
the owner that marked the bitmap busy, it's safe to merge it using it as
a read only source.

It is not safe in the general case to allow users to read from in-use
bitmaps, so create an internal variant that foregoes the safety
checking.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow cf0cd293c6 block/backup: add 'never' policy to bitmap sync mode
This adds a "never" policy for bitmap synchronization. Regardless of if
the job succeeds or fails, we never update the bitmap. This can be used
to perform differential backups, or simply to avoid the job modifying a
bitmap.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-7-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00