No other filter driver has a .bdrv_co_truncate() implementation, and
there is no need to because the general block layer code can handle it
just as well.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190918095144.955-3-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Make the filter truncation (passing it through to bs->file) a
first-class citizen and handle it exactly as if it was the filter
driver's native implementation of .bdrv_co_truncate().
I do not see a reason not to, it makes the code a bit shorter, and may
be even more correct because this gets us to finish the write_req that
we prepared before (may be important to e.g. bring dirty bitmaps to the
correct size).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190918095144.955-2-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2 v3 images require every snapshot table entry to have at least 16
bytes of extra data. If they do not, let qemu-img check -r all fix it.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-15-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The user cannot choose which snapshots are removed. This is fine
because we have chosen the maximum snapshot table size to be so large
(65536 entries) that it cannot be reasonably reached. If the snapshot
table exceeds this size, the image has probably been corrupted in some
way; in this case, it is most important to just make the image usable
such that the user can copy off at least the active layer.
(Also note that the snapshots will be removed only with "-r all", so a
plain "check" or "check -r leaks" will not delete any data.)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-14-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
We currently refuse to open qcow2 images with overly long snapshot
tables. This patch makes qemu-img check -r all drop all offending
entries past what we deem acceptable.
The user cannot choose which snapshots are removed. This is fine
because we have chosen the maximum snapshot table size to be so large
(64 MB) that it cannot be reasonably reached. If the snapshot table
exceeds this size, the image has probably been corrupted in some way; in
this case, it is most important to just make the image usable such that
the user can copy off at least the active layer.
(Also note that the snapshots will be removed only with "-r all", so a
plain "check" or "check -r leaks" will not delete any data.)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-13-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
When repairing the snapshot table, we truncate entries that have too
much extra data. This frees up space that we do not have to count
towards the snapshot table size.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-12-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The only case where we currently reject snapshot table entries is when
they have too much extra data. Fix them with qemu-img check -r all by
counting it as a corruption, reducing their extra_data_size, and then
letting qcow2_check_fix_snapshot_table() do the rest.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-11-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_check_read_snapshot_table() can perform consistency checks, but it
cannot fix everything. Specifically, it cannot allocate new clusters,
because that should wait until the refcount structures are known to be
consistent (i.e., after qcow2_check_refcounts()). Thus, it cannot call
qcow2_write_snapshots().
Do that in qcow2_check_fix_snapshot_table(), which is called after
qcow2_check_refcounts().
Currently, there is nothing that would set result->corruptions, so this
is a no-op. A follow-up patch will change that.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-10-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reading the snapshot table can fail. That is a problem when we want to
repair the image.
Therefore, stop reading the snapshot table in qcow2_do_open() in check
mode. Instead, add a new function qcow2_check_read_snapshot_table()
that reads the snapshot table at a later point. In the future, we want
to handle errors here and fix them.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-9-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2 v3 requires every snapshot table entry to have two extra data
fields: The 64-bit VM state size, and the virtual disk size. Both are
optional for v2 images, so they may not be present.
qcow2_upgrade() therefore should update the snapshot table to ensure all
entries have these extra data fields.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1727347
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-8-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This does not make sense right now, but it will make sense once we need
to do more than to just update s->qcow_version.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-7-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Updating the snapshot list will be useful when upgrading a v2 image to
v3, so we will need to call this function in qcow2.c.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-6-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The qcow2 specification says to ignore unknown extra data fields in
snapshot table entries. Currently, we discard it whenever we update the
image, which is a bit different from "ignore".
This patch makes the qcow2 driver keep all unknown extra data fields
when updating an image's snapshot table.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-5-mreitz@redhat.com
[mreitz: Adjusted comments as proposed by Eric]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-4-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-3-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
mirror_exit_common() may be called twice (if it is called from
mirror_prepare() and fails, it will be called from mirror_abort()
again).
In such a case, many of the pointers in the MirrorBlockJob object will
already be freed. This can be seen most reliably for s->target, which
is set to NULL (and then dereferenced by blk_bs()).
Cc: qemu-stable@nongnu.org
Fixes: 737efc1eda
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191014153931.20699-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
No reason to limit buffered copy to one cluster. Let's allow up to 1
MiB.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191022111805.3432-7-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Currently total allocation for parallel requests to block-copy instance
is unlimited. Let's limit it to 128 MiB.
For now block-copy is used only in backup, so actually we limit total
allocation for backup job.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191022111805.3432-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Merge copying code into one function block_copy_do_copy, which only
calls bdrv_ io functions and don't do any synchronization (like dirty
bitmap set/reset).
Refactor block_copy() function so that it takes full decision about
size of chunk to be copied and does all the synchronization (checking
intersecting requests, set/reset dirty bitmaps).
It will help:
- introduce parallel processing of block_copy iterations: we need to
calculate chunk size, start async chunk copying and go to the next
iteration
- simplify synchronization improvement (like memory limiting in
further commit and reducing critical section (now we lock the whole
requested range, when actually we need to lock only dirty region
which we handle at the moment))
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191022111805.3432-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Large copy range may imply memory allocation and large io effort, so
using 2G copy range request may be bad idea. Let's limit it to 16 MiB.
It also helps the following patch to refactor copy-with-offload
fallback to copy-with-bounce-buffer.
Note, that total memory usage of backup is still not limited, it will
be fixed in further commit.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191022111805.3432-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Move bounce_buffer allocation block_copy_with_bounce_buffer. This
commit simplifies further work on implementing copying by larger chunks
(of different size) and further asynchronous handling of block_copy
iterations (with help of block/aio_task API).
Allocation works fast, a lot faster than disk io, so it's not a problem
that we now allocate/free bounce_buffer more times. And we anyway will
have to allocate several bounce_buffers for parallel execution of loop
iterations in future.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191022111805.3432-2-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This reverts commit 9adc1cb49a.
"mirror: Only mirror granularity-aligned chunks"
Since previous commit unaligned chunks are supported by
do_sync_target_write.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191011090711.19940-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Prior 9adc1cb49a do_sync_target_write had a bug: it reset aligned-up
region in the dirty bitmap, which means that we may not copy some bytes
and assume them copied, which actually leads to producing corrupted
target.
So 9adc1cb49a forced dirty bitmap granularity to be
request_alignment for mirror-top filter, so we are not working with
unaligned requests. However forcing large alignment obviously decreases
performance of unaligned requests.
This commit provides another solution for the problem: if unaligned
padding is already dirty, we can safely ignore it, as
1. It's dirty, it will be copied by mirror_iteration anyway
2. It's dirty, so skipping it now we don't increase dirtiness of the
bitmap and therefore don't damage "synchronicity" of the
write-blocking mirror.
If unaligned padding is not dirty, we just write it, no reason to touch
dirty bitmap if we succeed (on failure we'll set the whole region
ofcourse, but we loss "synchronicity" on failure anyway).
Note: we need to disable dirty_bitmap, otherwise we will not be able to
see in do_sync_target_write bitmap state before current operation. We
may of course check dirty bitmap before the operation in
bdrv_mirror_top_do_write and remember it, but we don't need active
dirty bitmap for write-blocking mirror anyway.
New code-path is unused until the following commit reverts
9adc1cb49a.
Suggested-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191011090711.19940-5-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add blk write function with qiov_offset parameter. It's needed for the
following commit.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191011090711.19940-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
do_sync_target_write is called from bdrv_mirror_top_do_write after
write/discard operation, all inside active_write/active_write_settle
protecting us from mirror iteration. So the whole area is dirty for
sure, no reason to examine dirty bitmap.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20191011090711.19940-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
There are three page size in qemu:
real host page size
host page size
target page size
All of them have dedicate variable to represent. For the last two, we
use the same form in the whole qemu project, while for the first one we
use two forms: qemu_real_host_page_size and getpagesize().
qemu_real_host_page_size is defined to be a replacement of
getpagesize(), so let it serve the role.
[Note] Not fully tested for some arch or device.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191013021145.16011-3-richardw.yang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
qcow2_detect_metadata_preallocation() calls qcow2_get_refcount() which
requires s->lock to be taken to protect its accesses to the refcount
table and refcount blocks. However, nothing in this code path actually
took the lock. This could cause the same cache entry to be used by two
requests at the same time, for different tables at different offsets,
resulting in image corruption.
As it would be preferable to base the detection on consistent data (even
though it's just heuristics), let's take the lock not only around the
qcow2_get_refcount() calls, but around the whole function.
This patch takes the lock in qcow2_co_block_status() earlier and asserts
in qcow2_detect_metadata_preallocation() that we hold the lock.
Fixes: 69f47505ee
Cc: qemu-stable@nongnu.org
Reported-by: Michael Weiser <michael.weiser@gmx.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Michael Weiser <michael.weiser@gmx.de>
Reviewed-by: Michael Weiser <michael.weiser@gmx.de>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
After commit 00e30f05de, there is no more "goto error" points
after job creation, so after "error:" @job is always NULL and we don't
need roll-back job creation.
Reported-by: Coverity (CID 1406402)
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Implement reconnect. To achieve this:
1. add new modes:
connecting-wait: means, that reconnecting is in progress, and there
were small number of reconnect attempts, so all requests are
waiting for the connection.
connecting-nowait: reconnecting is in progress, there were a lot of
attempts of reconnect, all requests will return errors.
two old modes are used too:
connected: normal state
quit: exiting after fatal error or on close
Possible transitions are:
* -> quit
connecting-* -> connected
connecting-wait -> connecting-nowait (transition is done after
reconnect-delay seconds in connecting-wait mode)
connected -> connecting-wait
2. Implement reconnect in connection_co. So, in connecting-* mode,
connection_co, tries to reconnect unlimited times.
3. Retry nbd queries on channel error, if we are in connecting-wait
state.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20191009084158.15614-3-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The only reason I can imagine for this strange code at the very-end of
bdrv_reopen_commit is the fact that bs->read_only updated after
calling drv->bdrv_reopen_commit in bdrv_reopen_commit. And in the same
time, prior to previous commit, qcow2_reopen_bitmaps_rw did a wrong
check for being writable, when actually it only need writable file
child not self.
So, as it's fixed, let's move things to correct place.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Acked-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190927122355.7344-10-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
- Correct check for write access to file child, and in correct place
(only if we want to write).
- Support reopen rw -> rw (which will be used in following commit),
for example, !bdrv_dirty_bitmap_readonly() is not a corruption if
bitmap is marked IN_USE in the image.
- Consider unexpected bitmap as a corruption and check other
combinations of in-image and in-RAM bitmaps.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190927122355.7344-9-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
qcow2_reopen_bitmaps_ro wants to store bitmaps and then mark them all
readonly. But the latter don't work, as
qcow2_store_persistent_dirty_bitmaps removes bitmaps after storing.
It's OK for inactivation but bad idea for reopen-ro. And this leads to
the following bug:
Assume we have persistent bitmap 'bitmap0'.
Create external snapshot
bitmap0 is stored and therefore removed
Commit snapshot
now we have no bitmaps
Do some writes from guest (*)
they are not marked in bitmap
Shutdown
Start
bitmap0 is loaded as valid, but it is actually broken! It misses
writes (*)
Incremental backup
it will be inconsistent
So, let's stop removing bitmaps on reopen-ro. But don't rejoice:
reopening bitmaps to rw is broken too, so the whole scenario will not
work after this patch and we can't enable corresponding test cases in
260 iotests still. Reopening bitmaps rw will be fixed in the following
patches.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190927122355.7344-7-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
The function is unused, drop it.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190927122355.7344-6-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
Firstly, no reason to optimize failure path. Then, function name is
ambiguous: it checks for readonly and similar things, but someone may
think that it will ignore normal bitmaps which was just unchanged, and
this is in bad relation with the fact that we should drop IN_USE flag
for unchanged bitmaps in the image.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190927122355.7344-5-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
bdrv_dirty_bitmap_next is always used in same pattern. So, split it
into _next and _first, instead of combining two functions into one and
add FOR_EACH_DIRTY_BITMAP macro.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190916141911.5255-5-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
mutex field is just a pointer to bs->dirty_bitmap_mutex, so no needs
to store it in BdrvDirtyBitmap when we have bs pointer in it (since
previous patch).
Drop mutex field. Constantly use bdrv_dirty_bitmaps_lock/unlock in
block/dirty-bitmap.c to make it more obvious that it's not per-bitmap
lock. Still, for simplicity, leave bdrv_dirty_bitmap_lock/unlock
functions as an external API.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190916141911.5255-4-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
"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>
* 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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
