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>
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h). It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.
Include qemu/main-loop.h only where it's needed. Touching it now
recompiles only some 1700 objects. For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the
others, they shrink only slightly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Commit b76b4f60 allowed '-o compat=v3' as an alias for the
less-appealing '-o compat=1.1' for 'qemu-img create' since we want to
use the QMP form as much as possible, but forgot to do likewise for
qemu-img amend. Also, it doesn't help that '-o help' doesn't list our
new preferred spellings.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch is used in the 'block/stream: introduce a bottom node'
that is following. Instead of the base node, the caller may pass
the node that has the base as its backing image to the function
bdrv_is_allocated_above() with a new parameter include_base = true
and get rid of the dependency on the base that may change during
commit/stream parallel jobs. Now, if the specified base is not
found in the backing image chain, the QEMU will abort.
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1559152576-281803-2-git-send-email-andrey.shinkevich@virtuozzo.com
[mreitz: Squashed in the following as a rebase on conflicting patches:]
Message-id: e3cf99ae-62e9-8b6e-5a06-d3c8b9363b85@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This adds a new parameter to blk_new() which requires its callers to
declare from which AioContext this BlockBackend is going to be used (or
the locks of which AioContext need to be taken anyway).
The given context is only stored and kept up to date when changing
AioContexts. Actually applying the stored AioContext to the root node
is saved for another commit.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
drv_co_block_status digs bs->file for additional, more accurate search
for hole inside region, reported as DATA by bs since 5daa74a6eb.
This accuracy is not free: assume we have qcow2 disk. Actually, qcow2
knows, where are holes and where is data. But every block_status
request calls lseek additionally. Assume a big disk, full of
data, in any iterative copying block job (or img convert) we'll call
lseek(HOLE) on every iteration, and each of these lseeks will have to
iterate through all metadata up to the end of file. It's obviously
ineffective behavior. And for many scenarios we don't need this lseek
at all.
However, lseek is needed when we have metadata-preallocated image.
So, let's detect metadata-preallocation case and don't dig qcow2's
protocol file in other cases.
The idea is to compare allocation size in POV of filesystem with
allocations size in POV of Qcow2 (by refcounts). If allocation in fs is
significantly lower, consider it as metadata-preallocation case.
102 iotest changed, as our detector can't detect shrinked file as
metadata-preallocation, which don't seem to be wrong, as with metadata
preallocation we always have valid file length.
Two other iotests have a slight change in their QMP output sequence:
Active 'block-commit' returns earlier because the job coroutine yields
earlier on a blocking operation. This operation is loading the refcount
blocks in qcow2_detect_metadata_preallocation().
Suggested-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If COW areas of the newly allocated clusters are zeroes on the backing
image, efficient bdrv_write_zeroes(flags=BDRV_REQ_NO_FALLBACK) can be
used on the whole cluster instead of writing explicit zero buffers later
in perform_cow().
iotest 060:
write to the discarded cluster does not trigger COW anymore.
Use a backing image instead.
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Message-id: 20190516142749.81019-2-anton.nefedov@virtuozzo.com
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Do encryption/decryption in threads, like it is already done for
compression. This improves asynchronous encrypted io.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-9-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Encryption will be done in threads, to take benefit of it, we should
move it out of the lock first.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-8-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Background: decryption will be done in threads, to take benefit of it,
we should move it out of the lock first.
But let's go further: it turns out, that only
qcow2_get_cluster_offset() needs locking, so reduce locking to it.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190506142741.41731-7-vsementsov@virtuozzo.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Move generic part out of qcow2_co_do_compress, to reuse it for
encryption and rename things that would be shared with encryption path.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Move compression-on-threads to separate file. Encryption will be in it
too.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2.h depends on block_int.h. Compilation isn't broken currently only
due to block_int.h always included before qcow2.h. Though, it seems
better to directly include block_int.h in qcow2.h.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-2-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
When an L2 table entry points to a compressed cluster the space used
by the data is specified in 512-byte sectors. This size is independent
from BDRV_SECTOR_SIZE and is specific to the qcow2 file format.
The QCOW2_COMPRESSED_SECTOR_SIZE constant defined in this patch makes
this explicit.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The last user of this field disappeared when we replace the
sector-based bdrv_write() with the byte-based bdrv_pwrite().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch fixes a few things in the way error codes are handled in
the qcow2 compression code:
a) qcow2_co_pwritev_compressed() expects qcow2_co_compress() to only
return -1 or -2 on failure, but this is not correct. Since the
change from qcow2_compress() to qcow2_co_compress() in commit
ceb029cd6f the new code can also return -EINVAL (although
there does not seem to exist any code path that would cause that
error in the current implementation).
b) -1 and -2 are ad-hoc error codes defined in qcow2_compress().
This patch replaces them with standard constants from errno.h.
c) Both qcow2_compress() and qcow2_co_do_compress() return a negative
value on failure, but qcow2_co_pwritev_compressed() stores the
value in an unsigned data type.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
make_completely_empty() is an optimisated path for bdrv_make_empty()
where completely new metadata is created inside the image file instead
of going through all clusters and discarding them. For an external data
file, however, we actually need to do discard operations on the data
file; just overwriting the qcow2 file doesn't get rid of the data.
The necessary slow path with an explicit discard operation already
exists for other cases. Use it for external data files, too.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
preallocate_co() already gave the data file the full size without
forwarding the requested preallocation mode to the protocol. When
bdrv_co_truncate() was called later with the preallocation mode, the
file didn't actually grow any more, so the data file stayed unallocated
even if full preallocation was requested.
Pass the right preallocation mode to preallocate_co() and remove the
second bdrv_co_truncate() to fix this. As a side effect, the ugly
one-byte write in preallocate_co() is replaced with a truncate call,
now leaving the last block unallocated on the protocol level as it
should be.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
We'll add a bdrv_co_truncate() call in the next patch which can return
an Error that we don't want to discard. So add an errp parameter to
preallocate_co().
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Limiting the allocation to INT_MAX bytes isn't particularly clever
because it means that the final cluster will be a partial cluster which
will be completed through a COW operation. This results in unnecessary
data read and write requests which lead to an unwanted non-sparse
filesystem block for metadata preallocation.
Align the maximum allocation size down to the cluster size to avoid this
situation.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
With an external data file, preallocate_co() must write the final byte
to the external data file, not to the qcow2 image file.
This is harmless for preallocation of newly created images (only the
qcow2 file size is increased to the virtual disk size while it should be
much smaller), but with preallocated resize, it could in theory cause
visible corruption if the metadata of the image is larger than the data
(e.g. lots of bitmaps).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
We were trying to check whether bdrv_open_blockdev_ref() returned
success, but accidentally checked the wrong variable. Spotted by
Coverity (CID 1399703).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
If we reopen a BlockDriverState and there is an option that is present
in bs->options but missing from the new set of options then we have to
return an error unless the driver is able to reset it to its default
value.
This patch adds a new 'mutable_opts' field to BlockDriver. This is
a list of runtime options that can be modified during reopen. If an
option in this list is unspecified on reopen then it must be reset (or
return an error).
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Since we now load all bitmaps into memory anyway, we can just truncate
them in-memory and then flush them back to disk. Just in case, we will
still check and enforce that this shortcut is valid -- i.e. that any
bitmap described on-disk is indeed in-memory and can be modified.
If there are any inconsistent bitmaps, we refuse to allow the truncate
as we do not actually load these bitmaps into memory, and it isn't safe
or reasonable to attempt to truncate corrupted data.
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190311185147.52309-4-vsementsov@virtuozzo.com
[vsementsov: drop bitmap flushing, fix block comments style]
Signed-off-by: John Snow <jsnow@redhat.com>
Provide an option to force QEMU to always keep the external data file
consistent as a standalone read-only raw image.
At the moment, this means making sure that write_zeroes requests are
forwarded to the data file instead of just updating the metadata, and
checking that no backing file is used.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Rather than requiring that the external data file node is passed
explicitly when creating the qcow2 node, store the filename in the
designated header extension during .bdrv_create and read it from there
as a default during .bdrv_open.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This changes the qcow2 implementation to direct all guest data I/O to
s->data_file rather than bs->file, while metadata I/O still uses
bs->file. At the moment, this is still always the same, but soon we'll
add options to set s->data_file to an external data file.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Offset 0 cannot be assumed to mean an unallocated cluster any more.
Instead, the cluster type needs to be checked.
*file must refer to the data file instead of the image file if a valid
offset is returned from qcow2_co_block_status().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qcow2_alloc_compressed_cluster_offset() used to return the cluster
offset for success and 0 for error. This doesn't only conflict with 0 as
a valid host offset, but also loses the error code.
Similar to the change made to qcow2_alloc_cluster_offset() for
uncompressed clusters in commit 148da7ea9d, make the function return
0/-errno and return the allocated cluster offset in a by-reference
parameter.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds basic constants, struct fields and helper function for
external data file support to the implementation.
QCOW2_INCOMPAT_MASK and QCOW2_AUTOCLEAR_MASK are not updated yet so that
opening images with an external data file still fails (we don't handle
them correctly yet).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Image creation already involves a bdrv_co_truncate() call, which allows
to specify a preallocation mode. Just pass the right mode there and
remove the code that is made redundant by this.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
QEMU 2.12 (commit 1221fe6f63) introduced
a new setting called l2-cache-entry-size that allows making entries on
the qcow2 L2 cache smaller than the cluster size.
I have been performing several tests with different cluster and entry
sizes and all of them show that reducing the entry size (aka L2 slice)
consistently improves I/O performance, notably during random I/O (all
tests done with sequential I/O show similar results). This is to be
expected because loading and evicting an L2 slice is more expensive
the larger the slice is.
Here are some numbers on fully populated 40GB qcow2 images. The
rightmost column represents the maximum L2 cache size in both cases.
Cluster size = 64 KB
|-------------+--------------+--------------+--------------|
| | 1MB L2 cache | 3MB L2 cache | 5MB L2 cache |
|-------------+--------------+--------------+--------------|
| 4KB slices | 6545 IOPS | 12045 IOPS | 55680 IOPS |
| 16KB slices | 5177 IOPS | 9798 IOPS | 56278 IOPS |
| 64KB slices | 2718 IOPS | 5326 IOPS | 57355 IOPS |
|-------------+--------------+--------------+--------------|
Cluster size = 256 KB
|--------------+----------------+--------------+-----------------|
| | 512KB L2 cache | 1MB L2 cache | 1280KB L2 cache |
|--------------+----------------+--------------+-----------------|
| 4KB slices | 8539 IOPS | 21071 IOPS | 55417 IOPS |
| 64KB slices | 3598 IOPS | 9772 IOPS | 57687 IOPS |
| 256KB slices | 1415 IOPS | 4120 IOPS | 58001 IOPS |
|--------------+----------------+--------------+-----------------|
As can be seen in the numbers, the only exception to the rule is when
the cache is large enough to hold all L2 tables. This is also to be
expected because in this case no cache entry is ever evicted so
reducing its size doesn't bring any benefit.
This patch sets the default L2 cache entry size to 4KB except when the
cache is large enough for the whole disk.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
- Block graph change fixes (avoid loops, cope with non-tree graphs)
- bdrv_set_aio_context() related fixes
- HMP snapshot commands: Use only tag, not the ID to identify snapshots
- qmeu-img, commit: Error path fixes
- block/nvme: Build fix for gcc 9
- MAINTAINERS updates
- Fix various issues with bdrv_refresh_filename()
- Fix various iotests
- Include LUKS overhead in qemu-img measure for qcow2
- A fix for vmdk's image creation interface
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches:
- Block graph change fixes (avoid loops, cope with non-tree graphs)
- bdrv_set_aio_context() related fixes
- HMP snapshot commands: Use only tag, not the ID to identify snapshots
- qmeu-img, commit: Error path fixes
- block/nvme: Build fix for gcc 9
- MAINTAINERS updates
- Fix various issues with bdrv_refresh_filename()
- Fix various iotests
- Include LUKS overhead in qemu-img measure for qcow2
- A fix for vmdk's image creation interface
# gpg: Signature made Mon 25 Feb 2019 14:18:15 GMT
# gpg: using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (71 commits)
iotests: Skip 211 on insufficient memory
vmdk: false positive of compat6 with hwversion not set
iotests: add LUKS payload overhead to 178 qemu-img measure test
qcow2: include LUKS payload overhead in qemu-img measure
iotests.py: s/_/-/g on keys in qmp_log()
iotests: Let 045 be run concurrently
iotests: Filter SSH paths
iotests.py: Filter filename in any string value
iotests.py: Add is_str()
iotests: Fix 207 to use QMP filters for qmp_log
iotests: Fix 232 for LUKS
iotests: Remove superfluous rm from 232
iotests: Fix 237 for Python 2.x
iotests: Re-add filename filters
iotests: Test json:{} filenames of internal BDSs
block: BDS options may lack the "driver" option
block/null: Generate filename even with latency-ns
block/curl: Implement bdrv_refresh_filename()
block/curl: Harmonize option defaults
block/nvme: Fix bdrv_refresh_filename()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
LUKS encryption reserves clusters for its own payload data. The size of
this area must be included in the qemu-img measure calculation so that
we arrive at the correct minimum required image size.
(Ab)use the qcrypto_block_create() API to determine the payload
overhead. We discard the payload data that qcrypto thinks will be
written to the image.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190218104525.23674-2-stefanha@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This new field can be set by block drivers to list the runtime options
they accept that may influence the contents of the respective BDS. As of
a follow-up patch, this list will be used by the common
bdrv_refresh_filename() implementation to decide which options to put
into BDS.full_open_options (and consequently whether a JSON filename has
to be created), thus freeing the drivers of having to implement that
logic themselves.
Additionally, this patch adds the field to all of the block drivers that
need it and sets it accordingly.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190201192935.18394-22-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
If the backing file is overridden, this most probably does change the
guest-visible data of a BDS. Therefore, we will need to consider this
in bdrv_refresh_filename().
To see whether it has been overridden, we might want to compare
bs->backing_file and bs->backing->bs->filename. However,
bs->backing_file is changed by bdrv_set_backing_hd() (which is just used
to change the backing child at runtime, without modifying the image
header), so bs->backing_file most of the time simply contains a copy of
bs->backing->bs->filename anyway, so it is useless for such a
comparison.
This patch adds an auto_backing_file BDS field which contains the
backing file path as indicated by the image header, which is not changed
by bdrv_set_backing_hd().
Because of bdrv_refresh_filename() magic, however, a BDS's filename may
differ from what has been specified during bdrv_open(). Then, the
comparison between bs->auto_backing_file and bs->backing->bs->filename
may fail even though bs->backing was opened from bs->auto_backing_file.
To mitigate this, we can copy the real BDS's filename (after the whole
bdrv_open() and bdrv_refresh_filename() process) into
bs->auto_backing_file, if we know the former has been opened based on
the latter. This is only possible if no options modifying the backing
file's behavior have been specified, though. To simplify things, this
patch only copies the filename from the backing file if no options have
been specified for it at all.
Furthermore, there are cases where an overlay is created by qemu which
already contains a BDS's filename (e.g. in blockdev-snapshot-sync). We
do not need to worry about updating the overlay's bs->auto_backing_file
there, because we actually wrote a post-bdrv_refresh_filename() filename
into the image header.
So all in all, there will be false negatives where (as of a future
patch) bdrv_refresh_filename() will assume that the backing file differs
from what was specified in the image header, even though it really does
not. However, these cases should be limited to where (1) the user
actually did override something in the backing chain (e.g. by specifying
options for the backing file), or (2) the user executed a QMP command to
change some node's backing file (e.g. change-backing-file or
block-commit with @backing-file given) where the given filename does not
happen to coincide with qemu's idea of the backing BDS's filename.
Then again, (1) really is limited to -drive. With -blockdev or
blockdev-add, you have to adhere to the schema, so a user cannot give
partial "unimportant" options (e.g. by just setting backing.node-name
and leaving the rest to the image header). Therefore, trying to fix
this would mean trying to fix something for -drive only.
To improve on (2), we would need a full infrastructure to "canonicalize"
an arbitrary filename (+ options), so it can be compared against
another. That seems a bit over the top, considering that filenames
nowadays are there mostly for the user's entertainment.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20190201192935.18394-5-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Use new qemu_iovec_init_buf() instead of
qemu_iovec_init_external( ... , 1), which simplifies the code.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190218140926.333779-10-vsementsov@virtuozzo.com
Message-Id: <20190218140926.333779-10-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In the 'Format specific information' section of the 'qemu-img info'
command output, the supplemental information about existing QCOW2
bitmaps will be shown, such as a bitmap name, flags and granularity:
image: /vz/vmprivate/VM1/harddisk.hdd
file format: qcow2
virtual size: 64G (68719476736 bytes)
disk size: 3.0M
cluster_size: 1048576
Format specific information:
compat: 1.1
lazy refcounts: true
bitmaps:
[0]:
flags:
[0]: in-use
[1]: auto
name: back-up1
granularity: 65536
[1]:
flags:
[0]: in-use
[1]: auto
name: back-up2
granularity: 65536
refcount bits: 16
corrupt: false
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1549638368-530182-3-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Inform a user in case qcow2_get_specific_info fails to obtain
QCOW2 image specific information. This patch is preliminary to
the one "qcow2: Add list of bitmaps to ImageInfoSpecificQCow2".
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <1549638368-530182-2-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
In the block layer, synchronous APIs are often implemented by creating a
coroutine that calls the asynchronous coroutine-based implementation and
then waiting for completion with BDRV_POLL_WHILE().
For this to work with iothreads (more specifically, when the synchronous
API is called in a thread that is not the home thread of the block
device, so that the coroutine will run in a different thread), we must
make sure to call aio_wait_kick() at the end of the operation. Many
places are missing this, so that BDRV_POLL_WHILE() keeps hanging even if
the condition has long become false.
Note that bdrv_dec_in_flight() involves an aio_wait_kick() call. This
corresponds to the BDRV_POLL_WHILE() in the drain functions, but it is
generally not enough for most other operations because they haven't set
the return value in the coroutine entry stub yet. To avoid race
conditions there, we need to kick after setting the return value.
The race window is small enough that the problem doesn't usually surface
in the common path. However, it does surface and causes easily
reproducible hangs if the operation can return early before even calling
bdrv_inc/dec_in_flight, which many of them do (trivial error or no-op
success paths).
The bug in bdrv_truncate(), bdrv_check() and bdrv_invalidate_cache() is
slightly different: These functions even neglected to schedule the
coroutine in the home thread of the node. This avoids the hang, but is
obviously wrong, too. Fix those to schedule the coroutine in the right
AioContext in addition to adding aio_wait_kick() calls.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Do decompression in threads, like it is already done for compression.
This improves asynchronous compressed reads performance.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Allocate buffers locally and release qcow2 lock. Than, reads inside
qcow2_co_preadv_compressed may be done in parallel, however all
decompression is still done synchronously. Let's improve it in the
following commit.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Get rid of it here too.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
- make it look more like a pair of qcow2_compress - rename the function
and its parameters
- drop extra out_len variable, check filling of output buffer by strm
structure itself
- fix code style
- add some documentation
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Compression is done in threads in qcow2.c. We want to do decompression
in the same way, so, firstly, move it to the same file.
The only change is braces around if-body in decompress_buffer, to
satisfy checkpatch.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Give explicit size both for source and destination buffers, to make it
similar with decompression path and than cleanly reuse parameter
structure for decompression threads.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Use appropriate macro, corresponding to deflateInit2 spec.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The two thing that should be handled are cipher and ivgen. For ivgen
the solution is just mutex, as iv calculations should not be long in
comparison with encryption/decryption. And for cipher let's just keep
per-thread ciphers.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This doesn't have any practical effect at the moment because the
values of BDRV_SECTOR_SIZE, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE and
QCRYPTO_BLOCK_QCOW_SECTOR_SIZE are all the same (512 bytes), but
future encryption methods could have different requirements.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Taking the address of a field in a packed struct is a bad idea, because
it might not be actually aligned enough for that pointer type (and
thus cause a crash on dereference on some host architectures). Newer
versions of clang warn about this. Avoid the bug by not using the
"modify in place" byte swapping functions.
There are a few places where the in-place swap function is
used on something other than a packed struct field; we convert
those anyway, for consistency.
This patch was produced with the following spatch script
(and hand-editing to fold a few resulting overlength lines):
@@
expression E;
@@
-be16_to_cpus(&E);
+E = be16_to_cpu(E);
@@
expression E;
@@
-be32_to_cpus(&E);
+E = be32_to_cpu(E);
@@
expression E;
@@
-be64_to_cpus(&E);
+E = be64_to_cpu(E);
@@
expression E;
@@
-cpu_to_be16s(&E);
+E = cpu_to_be16(E);
@@
expression E;
@@
-cpu_to_be32s(&E);
+E = cpu_to_be32(E);
@@
expression E;
@@
-cpu_to_be64s(&E);
+E = cpu_to_be64(E);
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: John Snow <jsnow@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch aims to bring the following behavior:
1. We don't load bitmaps, when started in inactive mode. It's the case
of incoming migration. In this case we wait for bitmaps migration
through migration channel (if 'dirty-bitmaps' capability is enabled) or
for invalidation (to load bitmaps from the image).
2. We don't remove persistent bitmaps on inactivation. Instead, we only
remove bitmaps after storing. This is the only way to restore bitmaps,
if we decided to resume source after [failed] migration with
'dirty-bitmaps' capability enabled (which means, that bitmaps were not
stored).
3. We load bitmaps on open and any invalidation, it's ok for all cases:
- normal open
- migration target invalidation with dirty-bitmaps capability
(bitmaps are migrating through migration channel, the are not
stored, so they should have IN_USE flag set and will be skipped
when loading. However, it would fail if bitmaps are read-only[1])
- migration target invalidation without dirty-bitmaps capability
(normal load of the bitmaps, if migrated with shared storage)
- source invalidation with dirty-bitmaps capability
(skip because IN_USE)
- source invalidation without dirty-bitmaps capability
(bitmaps were dropped, reload them)
[1]: to accurately handle this, migration of read-only bitmaps is
explicitly forbidden in this patch.
New mechanism for not storing bitmaps when migrate with dirty-bitmaps
capability is introduced: migration filed in BdrvDirtyBitmap.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: John Snow <jsnow@redhat.com>
This variable doesn't work as it should, because it is actually cleared
in qcow2_co_invalidate_cache() by memset(). Drop it, as the following
patch will introduce new behavior.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[Maintainer edit -- touched up error message. --js]
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
From include/qapi/error.h:
* Pass an existing error to the caller with the message modified:
* error_propagate(errp, err);
* error_prepend(errp, "Could not frobnicate '%s': ", name);
Fei Li pointed out that doing error_propagate() first doesn't work
well when @errp is &error_fatal or &error_abort: the error_prepend()
is never reached.
Since I doubt fixing the documentation will stop people from getting
it wrong, introduce error_propagate_prepend(), in the hope that it
lures people away from using its constituents in the wrong order.
Update the instructions in error.h accordingly.
Convert existing error_prepend() next to error_propagate to
error_propagate_prepend(). If any of these get reached with
&error_fatal or &error_abort, the error messages improve. I didn't
check whether that's the case anywhere.
Cc: Fei Li <fli@suse.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181017082702.5581-2-armbru@redhat.com>
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The default cache-clean-interval is set to 10 minutes, in order to lower
the overhead of the qcow2 caches (before the default was 0, i.e.
disabled).
* For non-Linux platforms the default is kept at 0, because
cache-clean-interval is not supported there yet.
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The caches are now recalculated upon image resizing. This is done
because the new default behavior of assigning L2 cache relatively to
the image size, implies that the cache will be adapted accordingly
after an image resize.
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Sufficient L2 cache can noticeably improve the performance when using
large images with frequent I/O.
Previously, unless 'cache-size' was specified and was large enough, the
L2 cache was set to a certain size without taking the virtual image size
into account.
Now, the L2 cache assignment is aware of the virtual size of the image,
and will cover the entire image, unless the cache size needed for that is
larger than a certain maximum. This maximum is set to 1 MB by default
(enough to cover an 8 GB image with the default cluster size) but can
be increased or decreased using the 'l2-cache-size' option. This option
was previously documented as the *maximum* L2 cache size, and this patch
makes it behave as such, instead of as a constant size. Also, the
existing option 'cache-size' can limit the sum of both L2 and refcount
caches, as previously.
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The refcount cache size does not need to be set to its minimum value in
read_cache_sizes(), as it is set to at least its minimum value in
qcow2_update_options_prepare().
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Leonid Bloch <lbloch@janustech.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The generated qapi_event_send_FOO() take an Error ** argument. They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().
Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.
Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Pass read flags and write flags separately. This is needed to handle
coming BDRV_REQ_NO_SERIALISING clearly in following patches.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Do data compression in separate threads. This significantly improve
performance for qemu-img convert with -W (allow async writes) and -c
(compressed) options.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Make a separate function for compression to be parallelized later.
- use .avail_out field instead of .next_out to calculate size of
compressed data. It looks more natural and it allows to keep dest to
be void pointer
- set avail_out to be at least one byte less than input, to be sure
avoid inefficient compression earlier
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Not updating src_offset will result in wrong data being written to dst
image.
Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If we managed to allocate the clusters, but then failed to write the
data, there's a good chance that we'll still be able to free the
clusters again in order to avoid cluster leaks (the refcounts are
cached, so even if we can't write them out right now, we may be able to
do so when the VM is resumed after a werror=stop/enospc pause).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
block_crypto_open_opts_init() and block_crypto_create_opts_init()
contain a virtual visit of QCryptoBlockOptions and
QCryptoBlockCreateOptions less member "format", respectively.
Change their callers to put member "format" in the QDict, so they can
use the generated visitors for these types instead.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In the beginning of the function, we initialize the local variable to 0,
and in the body of the function, we check the assigned values and exit
the loop immediately. So here it can never be non-zero.
Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
All callers are coroutine_fns now, so we can just directly call
preallocate_co().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_truncate() is an operation that can block (even for a quite long
time, depending on the PreallocMode) in I/O paths that shouldn't block.
Convert it to a coroutine_fn so that we have the infrastructure for
drivers to make their .bdrv_co_truncate implementation asynchronous.
This change could potentially introduce new race conditions because
bdrv_truncate() isn't necessarily executed atomically any more. Whether
this is a problem needs to be evaluated for each block driver that
supports truncate:
* file-posix/win32, gluster, iscsi, nfs, rbd, ssh, sheepdog: The
protocol drivers are trivially safe because they don't actually yield
yet, so there is no change in behaviour.
* copy-on-read, crypto, raw-format: Essentially just filter drivers that
pass the request to a child node, no problem.
* qcow2: The implementation modifies metadata, so it needs to hold
s->lock to be safe with concurrent I/O requests. In order to avoid
double locking, this requires pulling the locking out into
preallocate_co() and using qcow2_write_caches() instead of
bdrv_flush().
* qed: Does a single header update, this is fine without locking.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
If qcow2_alloc_clusters_at() returns an error, we do need to negate it
to get back the positive errno code for error_setg_errno(), but we still
need to return the negative error code.
Fixes: 772d1f973f
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Flat unions may now have uncovered branches, so it is possible to get rid
of empty types defined for that purpose only.
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1529311206-76847-3-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The following pattern occurs in the .bdrv_co_create_opts() methods of
parallels, qcow, qcow2, qed, vhdx and vpc:
qobj = qdict_crumple_for_keyval_qiv(qdict, errp);
qobject_unref(qdict);
qdict = qobject_to(QDict, qobj);
if (qdict == NULL) {
ret = -EINVAL;
goto done;
}
v = qobject_input_visitor_new_keyval(QOBJECT(qdict));
[...]
ret = 0;
done:
qobject_unref(qdict);
[...]
return ret;
If qobject_to() fails, we return failure without setting errp. That's
wrong. As far as I can tell, it cannot fail here. Clean it up
anyway, by removing the useless conversion.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Configuration flows through the block subsystem in a rather peculiar
way. Configuration made with -drive enters it as QemuOpts.
Configuration made with -blockdev / blockdev-add enters it as QAPI
type BlockdevOptions. The block subsystem uses QDict, QemuOpts and
QAPI types internally. The precise flow is next to impossible to
explain (I tried for this commit message, but gave up after wasting
several hours). What I can explain is a flaw in the BlockDriver
interface that leads to this bug:
$ qemu-system-x86_64 -blockdev node-name=n1,driver=nfs,server.type=inet,server.host=localhost,path=/foo/bar,user=1234
qemu-system-x86_64: -blockdev node-name=n1,driver=nfs,server.type=inet,server.host=localhost,path=/foo/bar,user=1234: Internal error: parameter user invalid
QMP blockdev-add is broken the same way.
Here's what happens. The block layer passes configuration represented
as flat QDict (with dotted keys) to BlockDriver methods
.bdrv_file_open(). The QDict's members are typed according to the
QAPI schema.
nfs_file_open() converts it to QAPI type BlockdevOptionsNfs, with
qdict_crumple() and a qobject input visitor.
This visitor comes in two flavors. The plain flavor requires scalars
to be typed according to the QAPI schema. That's the case here. The
keyval flavor requires string scalars. That's not the case here.
nfs_file_open() uses the latter, and promptly falls apart for members
@user, @group, @tcp-syn-count, @readahead-size, @page-cache-size,
@debug.
Switching to the plain flavor would fix -blockdev, but break -drive,
because there the scalars arrive in nfs_file_open() as strings.
The proper fix would be to replace the QDict by QAPI type
BlockdevOptions in the BlockDriver interface. Sadly, that's beyond my
reach right now.
Next best would be to fix the block layer to always pass correctly
typed QDicts to the BlockDriver methods. Also beyond my reach.
What I can do is throw another hack onto the pile: have
nfs_file_open() convert all members to string, so use of the keyval
flavor actually works, by replacing qdict_crumple() by new function
qdict_crumple_for_keyval_qiv().
The pattern "pass result of qdict_crumple() to
qobject_input_visitor_new_keyval()" occurs several times more:
* qemu_rbd_open()
Same issue as nfs_file_open(), but since BlockdevOptionsRbd has only
string members, its only a latent bug. Fix it anyway.
* parallels_co_create_opts(), qcow_co_create_opts(),
qcow2_co_create_opts(), bdrv_qed_co_create_opts(),
sd_co_create_opts(), vhdx_co_create_opts(), vpc_co_create_opts()
These work, because they create the QDict with
qemu_opts_to_qdict_filtered(), which creates only string scalars.
The function sports a TODO comment asking for better typing; that's
going to be fun. Use qdict_crumple_for_keyval_qiv() to be safe.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There are numerous QDict functions that have been introduced for and are
used only by the block layer. Move their declarations into an own
header file to reflect that.
While qdict_extract_subqdict() is in fact used outside of the block
layer (in util/qemu-config.c), it is still a function related very
closely to how the block layer works with nested QDicts, namely by
sometimes flattening them. Therefore, its declaration is put into this
header as well and util/qemu-config.c includes it with a comment stating
exactly which function it needs.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20180509165530.29561-7-mreitz@redhat.com>
[Copyright note tweaked, superfluous includes dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When signaling a corruption on a read-only image, qcow2 already makes
fatal events non-fatal (i.e., they will not result in the image being
closed, and the image header's corrupt flag will not be set). This is
necessary because we cannot set the corrupt flag on read-only images,
and it is possible because further corruption of read-only images is
impossible.
Inactive images are effectively read-only, too, so we should do the same
for them. bdrv_is_writable() can tell us whether an image can actually
be written to, so use its result instead of !bs->read_only.
(Otherwise, the assert(!(bs->open_flags & BDRV_O_INACTIVE)) in
bdrv_co_pwritev() will fail, crashing qemu.)
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180606193702.7113-3-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Looking at the qcow2 code that is riddled with error_report() calls,
this is really how it should have been from the start.
Along the way, turn the target_version/current_version comparisons at
the beginning of qcow2_downgrade() into assertions (the caller has to
make sure these conditions are met), and rephrase the error message on
using compat=1.1 to get refcount widths other than 16 bits.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180509210023.20283-3-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
* Copy offloading for qemu-img convert (iSCSI, raw, and qcow2)
If the underlying storage supports copy offloading, qemu-img convert will
use it instead of performing reads and writes. This avoids data transfers
and thus frees up storage bandwidth for other purposes. SCSI EXTENDED COPY
and Linux copy_file_range(2) are used to implement this optimization.
* Drop spurious "WARNING: I\/O thread spun for 1000 iterations" warning
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Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging
Pull request
* Copy offloading for qemu-img convert (iSCSI, raw, and qcow2)
If the underlying storage supports copy offloading, qemu-img convert will
use it instead of performing reads and writes. This avoids data transfers
and thus frees up storage bandwidth for other purposes. SCSI EXTENDED COPY
and Linux copy_file_range(2) are used to implement this optimization.
* Drop spurious "WARNING: I\/O thread spun for 1000 iterations" warning
# gpg: Signature made Mon 04 Jun 2018 12:20:08 BST
# gpg: using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8
* remotes/stefanha/tags/block-pull-request:
main-loop: drop spin_counter
qemu-img: Convert with copy offloading
block-backend: Add blk_co_copy_range
iscsi: Implement copy offloading
iscsi: Create and use iscsi_co_wait_for_task
iscsi: Query and save device designator when opening
file-posix: Implement bdrv_co_copy_range
qcow2: Implement copy offloading
raw: Implement copy offloading
raw: Check byte range uniformly
block: Introduce API for copy offloading
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
vDPA support, fix to vhost blk RO bit handling, some include path
cleanups, NFIT ACPI table.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
acpi, vhost, misc: fixes, features
vDPA support, fix to vhost blk RO bit handling, some include path
cleanups, NFIT ACPI table.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Fri 01 Jun 2018 17:25:19 BST
# gpg: using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469
* remotes/mst/tags/for_upstream: (31 commits)
vhost-blk: turn on pre-defined RO feature bit
ACPI testing: test NFIT platform capabilities
nvdimm, acpi: support NFIT platform capabilities
tests/.gitignore: add entry for generated file
arch_init: sort architectures
ui: use local path for local headers
qga: use local path for local headers
colo: use local path for local headers
migration: use local path for local headers
usb: use local path for local headers
sd: fix up include
vhost-scsi: drop an unused include
ppc: use local path for local headers
rocker: drop an unused include
e1000e: use local path for local headers
ioapic: fix up includes
ide: use local path for local headers
display: use local path for local headers
trace: use local path for local headers
migration: drop an unused include
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The two callbacks are implemented quite similarly to the read/write
functions: bdrv_co_copy_range_from maps for read and calls into bs->file
or bs->backing depending on the allocation status; bdrv_co_copy_range_to
maps for write and calls into bs->file.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 20180601092648.24614-5-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When pulling in headers that are in the same directory as the C file (as
opposed to one in include/), we should use its relative path, without a
directory.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
MIN_REFCOUNT_CACHE_SIZE is 4 and the cluster size is guaranteed to be
at most 2MB, so the minimum refcount cache size (in bytes) is always
going to fit in a 32-bit integer.
Coverity doesn't know that, and since we're storing the result in a
uint64_t (*refcount_cache_size) it thinks that we need the 64 bits and
that we probably want to do a 64-bit multiplication to prevent the
result from being truncated.
This is a false positive in this case, but it's a fair warning.
We could do a 64-bit multiplication to get rid of it, but since we
know that a 32-bit variable is enough to store this value let's simply
reuse min_refcount_cache, make it a normal int and stop doing casts.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The L2 and refcount caches have default sizes that can be overridden
using the l2-cache-size and refcount-cache-size (an additional
parameter named cache-size sets the combined size of both caches).
Unless forced by one of the aforementioned parameters, QEMU will set
the unspecified sizes so that the L2 cache is 4 times larger than the
refcount cache.
This is based on the premise that the refcount metadata needs to be
only a fourth of the L2 metadata to cover the same amount of disk
space. This is incorrect for two reasons:
a) The amount of disk covered by an L2 table depends solely on the
cluster size, but in the case of a refcount block it depends on
the cluster size *and* the width of each refcount entry.
The 4/1 ratio is only valid with 16-bit entries (the default).
b) When we talk about disk space and L2 tables we are talking about
guest space (L2 tables map guest clusters to host clusters),
whereas refcount blocks are used for host clusters (including
L1/L2 tables and the refcount blocks themselves). On a fully
populated (and uncompressed) qcow2 file, image size > virtual size
so there are more refcount entries than L2 entries.
Problem (a) could be fixed by adjusting the algorithm to take into
account the refcount entry width. Problem (b) could be fixed by
increasing a bit the refcount cache size to account for the clusters
used for qcow2 metadata.
However this patch takes a completely different approach and instead
of keeping a ratio between both cache sizes it assigns as much as
possible to the L2 cache and the remainder to the refcount cache.
The reason is that L2 tables are used for every single I/O request
from the guest and the effect of increasing the cache is significant
and clearly measurable. Refcount blocks are however only used for
cluster allocation and internal snapshots and in practice are accessed
sequentially in most cases, so the effect of increasing the cache is
negligible (even when doing random writes from the guest).
So, make the refcount cache as small as possible unless the user
explicitly asks for a larger one.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 9695182c2eb11b77cb319689a1ebaa4e7c9d6591.1523968389.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Now that we can safely call QOBJECT() on QObject * as well as its
subtypes, we can have macros qobject_ref() / qobject_unref() that work
everywhere instead of having to use QINCREF() / QDECREF() for QObject
and qobject_incref() / qobject_decref() for its subtypes.
The replacement is mechanical, except I broke a long line, and added a
cast in monitor_qmp_cleanup_req_queue_locked(). Unlike
qobject_decref(), qobject_unref() doesn't accept void *.
Note that the new macros evaluate their argument exactly once, thus no
need to shout them.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180419150145.24795-4-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased, semantic conflict resolved, commit message improved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Checking reopen by existence of some bitmaps is wrong, as it may be
some other bitmaps, or on the other hand, user may remove bitmaps. This
criteria is bad. To simplify things and make behavior more predictable
let's just add a flag to remember, that we've already tried to load
bitmaps on open and do not want do it again.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20180411122606.367301-2-vsementsov@virtuozzo.com
[mreitz: Changed comment wording according to Eric Blake's suggestion]
Signed-off-by: Max Reitz <mreitz@redhat.com>
On reopen with existing bitmaps, instead of loading bitmaps, lets
reopen them if needed. This also fixes bitmaps migration through
shared storage.
Consider the case. Persistent bitmaps are stored on bdrv_inactivate.
Then, on destination process_incoming_migration_bh() calls
bdrv_invalidate_cache_all() which leads to
qcow2_load_autoloading_dirty_bitmaps() which fails if bitmaps are
already loaded on destination start.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20180320170521.32152-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This patch was generated using the following Coccinelle script:
@@
expression Obj;
@@
(
- qobject_to_qnum(Obj)
+ qobject_to(QNum, Obj)
|
- qobject_to_qstring(Obj)
+ qobject_to(QString, Obj)
|
- qobject_to_qdict(Obj)
+ qobject_to(QDict, Obj)
|
- qobject_to_qlist(Obj)
+ qobject_to(QList, Obj)
|
- qobject_to_qbool(Obj)
+ qobject_to(QBool, Obj)
)
and a bit of manual fix-up for overly long lines and three places in
tests/check-qjson.c that Coccinelle did not find.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20180224154033.29559-4-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: swap order from qobject_to(o, X), rebase to master, also a fix
to latent false-positive compiler complaint about hw/i386/acpi-build.c]
Signed-off-by: Eric Blake <eblake@redhat.com>
This adds a synchronous x-blockdev-create QMP command that can create
qcow2 images on a given node name.
We don't want to block while creating an image, so this is not the final
interface in all aspects, but BlockdevCreateOptionsQcow2 and
.bdrv_co_create() are what they actually might look like in the end. In
any case, this should be good enough to test whether we interpret
BlockdevCreateOptions as we should.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Instead of manually creating the BlockdevCreateOptions object, use a
visitor to parse the given options into the QAPI object.
This involves translation from the old command line syntax to the syntax
mandated by the QAPI schema. Option names are still checked against
qcow2_create_opts, so only the old option names are allowed on the
command line, even if they are translated in qcow2_create().
In contrast, new option values are optionally recognised besides the old
values: 'compat' accepts 'v2'/'v3' as an alias for '0.10'/'1.1', and
'encrypt.format' accepts 'qcow' as an alias for 'aes' now.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Once qcow2_co_create() can be called directly on an already existing
node, we must provide the 'full' and 'falloc' preallocation modes
outside of creating the image on the protocol layer. Fortunately, we
have preallocated truncate now which can provide this functionality.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Instead of passing the encryption format name and the QemuOpts down, use
the QCryptoBlockCreateOptions contained in BlockdevCreateOptions.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Instead of passing a separate BlockDriverState* into qcow2_co_create(),
make use of the BlockdevRef that is included in BlockdevCreateOptions.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
All of the simple options are now passed to qcow2_co_create() in a
BlockdevCreateOptions object. Still missing: node-name and the
encryption options.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Currently, qcow2_create() only parses the QemuOpts and then calls
qcow2_co_create() for the actual image creation, which includes both the
creation of the actual file on the file system and writing a valid empty
qcow2 image into that file.
The plan is that qcow2_co_create() becomes the function that implements
the functionality for a future 'blockdev-create' QMP command, which only
creates the qcow2 layer on an already opened file node.
This is a first step towards that goal: Let's move out anything that
deals with the protocol layer from qcow2_co_create() into
qcow2_create(). This means that qcow2_co_create() doesn't need a file
name any more.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The functions originally known as qcow2_create() and qcow2_create2()
are now called qcow2_co_create_opts() and qcow2_co_create(), which
matches the names of the BlockDriver callbacks that they will implement
at the end of this patch series.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This function checks that the offset and size of a table are valid.
While the offset checks are fine, the size check is too generic, since
it only verifies that the total size in bytes fits in a 64-bit
integer. In practice all tables used in qcow2 have much smaller size
limits, so the size needs to be checked again for each table using its
actual limit.
This patch generalizes this function by allowing the caller to specify
the maximum size for that table. In addition to that it allows passing
an Error variable.
The function is also renamed and made public since we're going to use
it in other parts of the code.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-8-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
QED's bdrv_invalidate_cache implementation would like to reuse functions
that acquire/release the metadata locks. Call it from coroutine context
to simplify the logic.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-6-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is called from qcow2_invalidate_cache in coroutine context (incoming
migration runs in a coroutine), so it's cleaner if metadata is always
loaded from a coroutine.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-4-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
They will be used to avoid recursively taking s->lock during
bdrv_open or bdrv_check.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-7-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches
# gpg: Signature made Mon 05 Mar 2018 17:45:51 GMT
# gpg: using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (38 commits)
block: Fix NULL dereference on empty drive error
qcow2: Replace align_offset() with ROUND_UP()
block/ssh: Add basic .bdrv_truncate()
block/ssh: Make ssh_grow_file() blocking
block/ssh: Pull ssh_grow_file() from ssh_create()
qemu-img: Make resize error message more general
qcow2: make qcow2_co_create2() a coroutine_fn
block: rename .bdrv_create() to .bdrv_co_create_opts()
Revert "IDE: Do not flush empty CDROM drives"
block: test blk_aio_flush() with blk->root == NULL
block: add BlockBackend->in_flight counter
block: extract AIO_WAIT_WHILE() from BlockDriverState
aio: rename aio_context_in_iothread() to in_aio_context_home_thread()
docs: document how to use the l2-cache-entry-size parameter
specs/qcow2: Fix documentation of the compressed cluster descriptor
iotest 033: add misaligned write-zeroes test via truncate
block: fix write with zero flag set and iovector provided
block: Drop unused .bdrv_co_get_block_status()
vvfat: Switch to .bdrv_co_block_status()
vpc: Switch to .bdrv_co_block_status()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
# Conflicts:
# include/block/block.h
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.
The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h. Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.
To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects. The next commit will
improve it further.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
The align_offset() function is equivalent to the ROUND_UP() macro so
there's no need to use the former. The ROUND_UP() name is also a bit
more explicit.
This patch uses ROUND_UP() instead of the slower QEMU_ALIGN_UP()
because align_offset() already requires that the second parameter is a
power of two.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180215131008.5153-1-berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_create2() calls qemu_co_mutex_lock(). Only a coroutine_fn may
call another coroutine_fn. In fact, qcow2_create2 is always called from
coroutine context.
Rename the function to add the "co" moniker and add coroutine_fn.
Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170705102231.20711-3-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
BlockDriver->bdrv_create() has been called from coroutine context since
commit 5b7e1542cf ("block: make
bdrv_create adopt coroutine").
Make this explicit by renaming to .bdrv_co_create_opts() and add the
coroutine_fn annotation. This makes it obvious to block driver authors
that they may yield, use CoMutex, or other coroutine_fn APIs.
bdrv_co_create is reserved for the QAPI-based version that Kevin is
working on.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170705102231.20711-2-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the qcow2 driver accordingly.
For now, we are ignoring the 'want_zero' hint. However, it should
be relatively straightforward to honor the hint as a way to return
larger *pnum values when we have consecutive clusters with the same
data/zero status but which differ only in having non-consecutive
mappings.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Now that the code is ready to handle L2 slices we can finally add an
option to allow configuring their size.
An L2 slice is the portion of an L2 table that is read by the qcow2
cache. Until now the cache was always reading full L2 tables, and
since the L2 table size is equal to the cluster size this was not very
efficient with large clusters. Here's a more detailed explanation of
why it makes sense to have smaller cache entries in order to load L2
data:
https://lists.gnu.org/archive/html/qemu-block/2017-09/msg00635.html
This patch introduces a new command-line option to the qcow2 driver
named l2-cache-entry-size (cf. l2-cache-size). The cache entry size
has the same restrictions as the cluster size: it must be a power of
two and it has the same range of allowed values, with the additional
requirement that it must not be larger than the cluster size.
The L2 cache entry size (L2 slice size) remains equal to the cluster
size for now by default, so this feature must be explicitly enabled.
Although my tests show that 4KB slices consistently improve
performance and give the best results, let's wait and make more tests
with different cluster sizes before deciding on an optimal default.
Now that the cache entry size is not necessarily equal to the cluster
size we need to reflect that in the MIN_L2_CACHE_SIZE documentation.
That minimum value is a requirement of the COW algorithm: we need to
read two L2 slices (and not two L2 tables) in order to do COW, see
l2_allocate() for the actual code.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: c73e5611ff4a9ec5d20de68a6c289553a13d2354.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The qcow2_truncate() code is mostly independent from whether
we're using L2 slices or full L2 tables, but in full and
falloc preallocation modes new L2 tables are allocated using
qcow2_alloc_cluster_link_l2(). Therefore the code needs to be
modified to ensure that all nb_clusters that are processed in each
call can be allocated with just one L2 slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 1fd7d272b5e7b66254a090b74cf2bed1cc334c0e.1517840877.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The BDRVQcow2State structure contains an l2_size field, which stores
the number of 64-bit entries in an L2 table.
For efficiency reasons we want to be able to load slices instead of
full L2 tables, so we need to know how many entries an L2 slice can
hold.
An L2 slice is the portion of an L2 table that is loaded by the qcow2
cache. At the moment that cache can only load complete tables,
therefore an L2 slice has the same size as an L2 table (one cluster)
and l2_size == l2_slice_size.
Later we'll allow smaller slices, but until then we have to use this
new l2_slice_size field to make the rest of the code ready for that.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: adb048595f9fb5dfb110c802a8b3c3be3b937f37.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to pass it
to qcow2_cache_table_release(). This is no longer necessary so this
parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: b74f17591af52f201de0ea3a3b2dd0a81932334d.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was never using the BlockDriverState parameter so it can
be safely removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 49c74fe8b3aead9056e61a85b145ce787d06262b.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
To maintain load/store disabled bitmap there is new approach:
- deprecate @autoload flag of block-dirty-bitmap-add, make it ignored
- store enabled bitmaps as "auto" to qcow2
- store disabled bitmaps without "auto" flag to qcow2
- on qcow2 open load "auto" bitmaps as enabled and others
as disabled (except in_use bitmaps)
Also, adjust iotests 165 and 176 appropriately.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20180202160752.143796-1-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
We don't need the can_write_zeroes_with_unmap field in
BlockDriverInfo, because it is redundant information with
supported_zero_flags & BDRV_REQ_MAY_UNMAP. Note that
BlockDriverInfo and supported_zero_flags are both per-device
settings, rather than global state about the driver as a
whole, which means one or both of these bits of information
can already be conditional. Let's audit how they were set:
crypto: always setting can_write_ to false is pointless (the
struct starts life zero-initialized), no use of supported_
nbd: just recently fixed to set can_write_ if supported_
includes MAY_UNMAP (thus this commit effectively reverts
bca80059e and solves the problem mentioned there in a more
global way)
file-posix, iscsi, qcow2: can_write_ is conditional, while
supported_ was unconditional; but passing MAY_UNMAP would
fail with ENOTSUP if the condition wasn't met
qed: can_write_ is unconditional, but pwrite_zeroes lacks
support for MAY_UNMAP and supported_ is not set. Perhaps
support can be added later (since it would be similar to
qcow2), but for now claiming false is no real loss
all other drivers: can_write_ is not set, and supported_ is
either unset or a passthrough
Simplify the code by moving the conditional into
supported_zero_flags for all drivers, then dropping the
now-unused BDI field. For callers that relied on
bdrv_can_write_zeroes_with_unmap(), we return the same
per-device settings for drivers that had conditions (no
observable change in behavior there); and can now return
true (instead of false) for drivers that support passthrough
(for example, the commit driver) which gives those drivers
the same fix as nbd just got in bca80059e. For callers that
relied on supported_zero_flags, we now have a few more places
that can avoid a wasted call to pwrite_zeroes() that will
just fail with ENOTSUP.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180126193439.20219-1-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-15-armbru@redhat.com>
qapi/qmp/types.h is a convenience header to include a number of
qapi/qmp/ headers. Since we rarely need all of the headers
qapi/qmp/types.h includes, we bypass it most of the time. Most of the
places that use it don't need all the headers, either.
Include the necessary headers directly, and drop qapi/qmp/types.h.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-9-armbru@redhat.com>
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.
While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
Persistent dirty bitmaps require a properly functioning
autoclear_features field, or we cannot track when an unsupporting
program might overwrite them. Therefore, we cannot support them for
compat=0.10 images.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171123020832.8165-3-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Since bdrv_co_preadv does all neccessary checks including
reading after the end of the backing file, avoid duplication
of verification before bdrv_co_preadv call.
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When trying to repair a dirty image, qcow2_check() may apparently
succeed (no really fatal error occurred that would prevent the check
from continuing), but if check_errors in the result object is non-zero,
we cannot trust the image to be usable.
Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728639
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-2-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Misaligned compressed write is not supported.
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Message-id: 1510654613-47868-2-git-send-email-anton.nefedov@virtuozzo.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
If an image contains persistent bitmaps, we cannot use the
fast path of bdrv_make_empty() to clear the image during
qemu-img commit, because that will lose the clusters related
to the bitmaps.
Also leave a comment in qcow2_read_extensions to remind future
feature additions to think about fast-path removal, since we
just barely fixed the same bug for LUKS encryption.
It's a pain that qemu-img has not yet been taught to manipulate,
or even at a very minimum display, information about persistent
bitmaps; instead, we have to use QMP commands. It's also a
pain that only qeury-block and x-debug-block-dirty-bitmap-sha256
will allow bitmap introspection; but the former requires the
node to be hooked to a block device, and the latter is experimental.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
After committing the qcow2 image contents into the base image, qemu-img
will call bdrv_make_empty to drop the payload in the layered image.
When this is done for qcow2 images, it blows away the LUKS encryption
header, making the resulting image unusable. There are two codepaths
for emptying a qcow2 image, and the second (slower) codepath leaves
the LUKS header intact, so force use of that codepath.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently if trying to change encryption parameters on a qcow2 image, qemu-img
will abort. We already explicitly check for attempt to change encrypt.format
but missed other parameters like encrypt.key-secret. Rather than list each
parameter, just blacklist changing of all parameters with a 'encrypt.' prefix.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The crypto header is initialized only when QEMU is creating a new
image, so there's no chance of this happening on a corrupted image.
If QEMU is really trying to allocate the header overlapping other
existing metadata sections then this is a serious bug in QEMU itself
so let's add an assertion.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: ae3d77f312fc0c5e0ac2bbd71676c0112eebe2e5.1509718618.git.berto@igalia.com
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_do_open() is checking that header.refcount_table_clusters is not
too large, but it doesn't check that it's greater than zero. Apart
from the fact that an image like that is obviously corrupted, trying
to use it crashes QEMU since we end up with a null s->refcount_table
after qcow2_refcount_init().
These images can however be repaired, so allow opening them if the
BDRV_O_CHECK flag is set.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: f9750f50c80359babba11062e88f5075a47e8e16.1509718618.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Some qcow2 functions (at least perform_cow()) expect s->lock to be
taken. Therefore, if we want to make use of them, we should execute
preallocate() (as "preallocate_co") in a coroutine so that we can use
the qemu_co_mutex_* functions.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171009215533.12530-3-mreitz@redhat.com
Cc: qemu-stable@nongnu.org
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
A qcow2 image file's length is not required to have a length that is a
multiple of the cluster size. However, qcow2_refcount_area() expects an
aligned value for its @start_offset parameter, so we need to round
@old_file_size up to the next cluster boundary.
Reported-by: Ping Li <pingl@redhat.com>
Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1414049
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171009215533.12530-2-mreitz@redhat.com
Cc: qemu-stable@nongnu.org
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
bdrv_truncate() has an errp parameter which is always set when an error
occurs. Let's use that instead of a plain strerror().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171009155431.14093-1-mreitz@redhat.com
Reviewed-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
BDRV_SECTOR_BITS is defined to be 9 in block.h (and BDRV_SECTOR_SIZE
is calculated from that), but there are still a couple of places where
we are using the literal value instead of the macro.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 20171009153856.20387-1-berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Now that bdrv_is_allocated accepts non-aligned inputs, we can
remove the TODO added in earlier refactoring.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. In the common case, allocation is unlikely to ever use
values that are not naturally sector-aligned, but it is possible
that byte-based values will let us be more precise about allocation
at the end of an unaligned file that can do byte-based access.
Changing the name of the function from bdrv_get_block_status_above()
to bdrv_block_status_above() ensures that the compiler enforces that
all callers are updated. Likewise, since it a byte interface allows
an offset mapping that might not be sector aligned, split the mapping
out of the return value and into a pass-by-reference parameter. For
now, the io.c layer still assert()s that all uses are sector-aligned,
but that can be relaxed when a later patch implements byte-based
block status in the drivers.
For the most part this patch is just the addition of scaling at the
callers followed by inverse scaling at bdrv_block_status(), plus
updates for the new split return interface. But some code,
particularly bdrv_block_status(), gets a lot simpler because it no
longer has to mess with sectors. Likewise, mirror code no longer
computes s->granularity >> BDRV_SECTOR_BITS, and can therefore drop
an assertion about alignment because the loop no longer depends on
alignment (never mind that we don't really have a driver that
reports sub-sector alignments, so it's not really possible to test
the effect of sub-sector mirroring). Fix a neighboring assertion to
use is_power_of_2 while there.
For ease of review, bdrv_get_block_status() was tackled separately.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert another internal
function (no semantic change), and rename it to is_zero() in the
process.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Not all callers care about which BDS owns the mapping for a given
range of the file. This patch merely simplifies the callers by
consolidating the logic in the common call point, while guaranteeing
a non-NULL file to all the driver callbacks, for no semantic change.
The only caller that does not care about pnum is bdrv_is_allocated,
as invoked by vvfat; we can likewise add assertions that the rest
of the stack does not have to worry about a NULL pnum.
Furthermore, this will also set the stage for a future cleanup: when
a caller does not care about which BDS owns an offset, it would be
nice to allow the driver to optimize things to not have to return
BDRV_BLOCK_OFFSET_VALID in the first place. In the case of fragmented
allocation (for example, it's fairly easy to create a qcow2 image
where consecutive guest addresses are not at consecutive host
addresses), the current contract requires bdrv_get_block_status()
to clamp *pnum to the limit where host addresses are no longer
consecutive, but allowing a NULL file means that *pnum could be
set to the full length of known-allocated data.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Now after shrinking the image, at the end of the image file, there might be a
tail that probably will never be used. So we can find the last used cluster and
cut the tail.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20170929121613.25997-3-pbutsykin@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170929121613.25997-2-pbutsykin@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Instead of sector offset, take the bytes offset when encrypting
or decrypting data.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170927125340.12360-6-berrange@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This is new code, but it is easier to read if it makes passes over
the image using bytes rather than sectors (and will get easier in
the future when bdrv_get_block_status is converted to byte-based).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch add shrinking of the image file for qcow2. As a result, this allows
us to reduce the virtual image size and free up space on the disk without
copying the image. Image can be fragmented and shrink is done by punching holes
in the image file.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20170918124230.8152-4-pbutsykin@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
In a previous patch (3dc6f86936) we
converted uses of error_report("warning:"... to use warn_report()
instead. This was to help standardise on a single method of printing
warnings to the user.
There appears to have been some cases that slipped through in patch sets
applied around the same time, this patch catches the few remaining
cases.
All of the warnings were changed using this command:
find ./* -type f -exec sed -i \
's|error_report(".*warning[,:] |warn_report("|Ig' {} +
Indentation fixed up manually afterwards.
Two messages were manually fixed up as well.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <eec8cba0d5434bd828639e5e45f12182490ff47d.1505158760.git.alistair.francis@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After calling qcow2_inactivate(), all qcow2 caches must be flushed, but this
may not happen, because the last call qcow2_store_persistent_dirty_bitmaps()
can lead to marking l2/refcont cache as dirty.
Let's move qcow2_store_persistent_dirty_bitmaps() before the caсhe flushing
to fix it.
Cc: qemu-stable@nongnu.org
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, a FOO_lookup is an array of strings terminated by a NULL
sentinel.
A future patch will generate enums with "holes". NULL-termination
will cease to work then.
To prepare for that, store the length in the FOO_lookup by wrapping it
in a struct and adding a member for the length.
The sentinel will be dropped next.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170822132255.23945-13-marcandre.lureau@redhat.com>
[Basically redone]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-16-git-send-email-armbru@redhat.com>
[Rebased]
The next commit will put it to use. May look pointless now, but we're
going to change the FOO_lookup's type, and then it'll help.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-13-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
The lookup tables have a sentinel, no need to make callers pass their
size.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-3-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Rebased, commit message corrected]
Most qcow2 files are uncompressed so it is wasteful to allocate (32 + 1)
* cluster_size + 512 bytes upfront. Allocate s->cluster_cache and
s->cluster_data when the first read operation is performance on a
compressed cluster.
The buffers are freed in .bdrv_close(). .bdrv_open() no longer has any
code paths that can allocate these buffers, so remove the free functions
in the error code path.
This patch can result in significant memory savings when many qcow2
disks are attached or backing file chains are long:
Before 12.81% (1,023,193,088B)
After 5.36% (393,893,888B)
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170821135530.32344-1-stefanha@redhat.com
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
There's a few cases which we're passing an Error pointer to a function
only to discard it immediately afterwards without checking it. In
these cases we can simply remove the variable and pass NULL instead.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170829120836.16091-1-berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
qcow2_co_pwritev_compressed() should not call bdrv_truncate()
if determining the size failed.
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It's been #if 0'd since its introduction in 2006, commit 585f8587.
We can revive dead code if we need it, but in the meantime, it has
bit-rotted (for example, not checking for failure in bdrv_getlength()).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Fix leak of the 'encryptopts' string, which was mistakenly
declared const.
Fix leak of QemuOpts entry which should not have been deleted
from the opts array.
Reported by: coverity
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170714103105.5781-1-berrange@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
We used MAX() instead of the intended MIN() when computing how many
sectors to view in the current loop iteration of qcow2_measure(),
and passed in a value of INT_MAX sectors instead of our more usual
limit of BDRV_REQUEST_MAX_SECTORS (the latter avoids 32-bit overflow
on conversion to bytes). For small files, the bug is harmless:
bdrv_get_block_status_above() clamps its *pnum answer to the BDS
size, regardless of any insanely larger input request. However, for
any file at least 2T in size, we can very easily end up going into an
infinite loop (the maximum of 0x100000000 sectors and INT_MAX is a
64-bit quantity, which becomes 0 when assigned to int; once nb_sectors
is 0, we never make progress).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Implement the preallocation modes falloc and full for growing qcow2
images.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613202107.10125-15-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function creates a collection of self-describing refcount
structures (including a new refcount table) at the end of a qcow2 image
file. Optionally, these structures can also describe a number of
additional clusters beyond themselves; this will be important for
preallocated truncation, which will place the data clusters and L2
tables there.
For now, we can use this function to replace the part of
alloc_refcount_block() that grows the refcount table (from which it is
actually derived).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-13-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
We can support PREALLOC_MODE_METADATA by invoking preallocate() in
qcow2_truncate().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170613202107.10125-12-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
preallocate() is and will be called only from places that do not
otherwise need to lock s->lock: Currently that is qcow2_create2(), as of
a future patch it will be called from qcow2_truncate(), too.
It therefore makes sense to move locking that mutex into preallocate()
itself.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-11-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This patch adds two new parameters to the preallocate() function so we
will be able to use it not just for preallocating a new image but also
for preallocated image growth.
The offset parameter allows the caller to specify a virtual offset from
which to start preallocating. For newly created images this is always 0,
but for preallocating growth this will be the old image length.
The new_length parameter specifies the supposed new length of the image
(basically the "end offset" for preallocation). During image truncation,
bdrv_getlength() will return the old image length so we cannot rely on
its return value then.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-10-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
blk_truncate() itself will pass that value to bdrv_truncate(), and all
callers of blk_truncate() just set the parameter to PREALLOC_MODE_OFF
for now.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-4-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
For block drivers that just pass a truncate request to the underlying
protocol, we can now pass the preallocation mode instead of aborting if
it is not PREALLOC_MODE_OFF.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-3-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add a PreallocMode parameter to the bdrv_truncate() function implemented
by each block driver. Currently, we always pass PREALLOC_MODE_OFF and no
driver accepts anything else.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170613202107.10125-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Use qcow2_calc_prealloc_size() to get the required file size.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20170705125738.8777-7-stefanha@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The image creation options parsed by qcow2_create() are also needed to
implement .bdrv_measure(). Extract the parsing code, including input
validation.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20170705125738.8777-6-stefanha@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The refcount metadata size calculation is inaccurate and can produce
numbers that are too small. This is bad because we should calculate a
conservative number - one that is guaranteed to be large enough.
This patch switches the approach to a fixed point calculation because
the existing equation is hard to solve when inaccuracies are taken care
of.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20170705125738.8777-5-stefanha@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Calculating the preallocated image size will be needed to implement
.bdrv_measure(). Extract the code out into a separate function.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20170705125738.8777-4-stefanha@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Store bitmaps and mark them read-only on reopening image as read-only.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170628120530.31251-21-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Store persistent dirty bitmaps in qcow2 image.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170628120530.31251-20-vsementsov@virtuozzo.com
[mreitz: Always assign ret in store_bitmap() in case of an error]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Auto loading bitmaps are bitmaps in Qcow2, with the AUTO flag set. They
are loaded when the image is opened and become BdrvDirtyBitmaps for the
corresponding drive.
Extra data in bitmaps is not supported for now.
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: 20170628120530.31251-12-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add bitmap extension as specified in docs/specs/qcow2.txt.
For now, just mirror extension header into Qcow2 state and check
constraints. Also, calculate refcounts for qcow2 bitmaps, to not break
qemu-img check.
For now, disable image resize if it has bitmaps. It will be fixed later.
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: 20170628120530.31251-9-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
While the crypto layer uses a fixed option name "key-secret",
the upper block layer may have a prefix on the options. e.g.
"encrypt.key-secret", in order to avoid clashes between crypto
option names & other block option names. To ensure the crypto
layer can report accurate error messages, we must tell it what
option name prefix was used.
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-19-berrange@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Now that all encryption keys must be provided upfront via
the QCryptoSecret API and associated block driver properties
there is no need for any explicit encryption handling APIs
in the block layer. Encryption can be handled transparently
within the block driver. We only retain an API for querying
whether an image is encrypted or not, since that is a
potentially useful piece of metadata to report to the user.
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-18-berrange@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This adds support for using LUKS as an encryption format
with the qcow2 file, using the new encrypt.format parameter
to request "luks" format. e.g.
# qemu-img create --object secret,data=123456,id=sec0 \
-f qcow2 -o encrypt.format=luks,encrypt.key-secret=sec0 \
test.qcow2 10G
The legacy "encryption=on" parameter still results in
creation of the old qcow2 AES format (and is equivalent
to the new 'encryption-format=aes'). e.g. the following are
equivalent:
# qemu-img create --object secret,data=123456,id=sec0 \
-f qcow2 -o encryption=on,encrypt.key-secret=sec0 \
test.qcow2 10G
# qemu-img create --object secret,data=123456,id=sec0 \
-f qcow2 -o encryption-format=aes,encrypt.key-secret=sec0 \
test.qcow2 10G
With the LUKS format it is necessary to store the LUKS
partition header and key material in the QCow2 file. This
data can be many MB in size, so cannot go into the QCow2
header region directly. Thus the spec defines a FDE
(Full Disk Encryption) header extension that specifies
the offset of a set of clusters to hold the FDE headers,
as well as the length of that region. The LUKS header is
thus stored in these extra allocated clusters before the
main image payload.
Aside from all the cryptographic differences implied by
use of the LUKS format, there is one further key difference
between the use of legacy AES and LUKS encryption in qcow2.
For LUKS, the initialiazation vectors are generated using
the host physical sector as the input, rather than the
guest virtual sector. This guarantees unique initialization
vectors for all sectors when qcow2 internal snapshots are
used, thus giving stronger protection against watermarking
attacks.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-14-berrange@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This converts the qcow2 driver to make use of the QCryptoBlock
APIs for encrypting image content, using the legacy QCow2 AES
scheme.
With this change it is now required to use the QCryptoSecret
object for providing passwords, instead of the current block
password APIs / interactive prompting.
$QEMU \
-object secret,id=sec0,file=/home/berrange/encrypted.pw \
-drive file=/home/berrange/encrypted.qcow2,encrypt.key-secret=sec0
The test 087 could be simplified since there is no longer a
difference in behaviour when using blockdev_add with encrypted
images for the running vs stopped CPU state.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-12-berrange@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Instead of requiring separate input/output buffers for
encrypting data, change qcow2_encrypt_sectors() to assume
use of a single buffer, encrypting in place. The current
callers all used the same buffer for input/output already.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-11-berrange@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Historically the qcow & qcow2 image formats supported a property
"encryption=on" to enable their built-in AES encryption. We'll
soon be supporting LUKS for qcow2, so need a more general purpose
way to enable encryption, with a choice of formats.
This introduces an "encrypt.format" option, which will later be
joined by a number of other "encrypt.XXX" options. The use of
a "encrypt." prefix instead of "encrypt-" is done to facilitate
mapping to a nested QAPI schema at later date.
e.g. the preferred syntax is now
qemu-img create -f qcow2 -o encrypt.format=aes demo.qcow2
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-8-berrange@redhat.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Change the 'int count' parameter in *pwrite_zeros, *pdiscard related
functions (and some others) to 'int bytes', as they both refer to bytes.
This helps with code legibility.
Signed-off-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Message-id: 20170609101808.13506-1-el13635@mail.ntua.gr
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
We already have functions for doing these calculations, so let's use
them instead of doing everything by hand. This makes the code a bit
more readable.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If the guest tries to write data that results on the allocation of a
new cluster, instead of writing the guest data first and then the data
from the COW regions, write everything together using one single I/O
operation.
This can improve the write performance by 25% or more, depending on
several factors such as the media type, the cluster size and the I/O
request size.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit d7086422b1 added a local_err
variable global to the qcow2_amend_options() function, so there's no
need to have this other one.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 20170511150337.21470-1-berto@igalia.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Passing a byte offset, but sector count, when we ultimately
want to operate on cluster granularity, is madness. Clean up
the external interfaces to take both offset and count as bytes,
while still keeping the assertion added previously that the
caller must align the values to a cluster. Then rename things
to make sure backports don't get confused by changed units:
instead of qcow2_discard_clusters() and qcow2_zero_clusters(),
we now have qcow2_cluster_discard() and qcow2_cluster_zeroize().
The internal functions still operate on clusters at a time, and
return an int for number of cleared clusters; but on an image
with 2M clusters, a single L2 table holds 256k entries that each
represent a 2M cluster, totalling well over INT_MAX bytes if we
ever had a request for that many bytes at once. All our callers
currently limit themselves to 32-bit bytes (and therefore fewer
clusters), but by making this function 64-bit clean, we have one
less place to clean up if we later improve the block layer to
support 64-bit bytes through all operations (with the block layer
auto-fragmenting on behalf of more-limited drivers), rather than
the current state where some interfaces are artificially limited
to INT_MAX at a time.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170507000552.20847-13-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
We've already improved discards to operate efficiently on the tail
of an unaligned qcow2 image; it's time to make a similar improvement
to write zeroes. The special case is only valid at the tail
cluster of a file, where we must recognize that any sectors beyond
the image end would implicitly read as zero, and therefore should
not penalize our logic for widening a partial cluster into writing
the whole cluster as zero.
However, note that for now, the special case of end-of-file is only
recognized if there is no backing file, or if the backing file has
the same length; that's because when the backing file is shorter
than the active layer, we don't have code in place to recognize
that reads of a sector unallocated at the top and beyond the backing
end-of-file are implicitly zero. It's not much of a real loss,
because most people don't use images that aren't cluster-aligned,
or where the active layer is a different size than the backing
layer (especially where the difference falls within a single cluster).
Update test 154 to cover the new scenarios, using two images of
intentionally differing length.
While at it, fix the test to gracefully skip when run as
./check -qcow2 -o compat=0.10 154
since the older format lacks zero clusters already required earlier
in the test.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170507000552.20847-11-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Treat plain zero clusters differently from allocated ones, so that
we can simplify the logic of checking whether an offset is present.
Do this by splitting QCOW2_CLUSTER_ZERO into two new enums,
QCOW2_CLUSTER_ZERO_PLAIN and QCOW2_CLUSTER_ZERO_ALLOC.
I tried to arrange the enum so that we could use
'ret <= QCOW2_CLUSTER_ZERO_PLAIN' for all unallocated types, and
'ret >= QCOW2_CLUSTER_ZERO_ALLOC' for allocated types, although
I didn't actually end up taking advantage of the layout.
In many cases, this leads to simpler code, by properly combining
cases (sometimes, both zero types pair together, other times,
plain zero is more like unallocated while allocated zero is more
like normal).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170507000552.20847-7-eblake@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
When calculating the number of reftable entries, we should actually use
the number of refblocks and not (wrongly[1]) re-calculate it.
[1] "Wrongly" means: Dividing the number of clusters by the number of
entries per refblock and rounding down instead of up.
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We now have macros in place to make it less verbose to add a scalar
to QDict and QList, so use them.
Patch created mechanically via:
spatch --sp-file scripts/coccinelle/qobject.cocci \
--macro-file scripts/cocci-macro-file.h --dir . --in-place
then touched up manually to fix a couple of '?:' back to original
spacing, as well as avoiding a long line in monitor.c.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170427215821.19397-7-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
As mentioned in commit 0c1bd46, we ignored requests to
discard the trailing cluster of an unaligned image. While
discard is an advisory operation from the guest standpoint,
(and we are therefore free to ignore any request), our
qcow2 implementation exploits the fact that a discarded
cluster reads back as 0. As long as we discard on cluster
boundaries, we are fine; but that means we could observe
non-zero data leaked at the tail of an unaligned image.
Enhance iotest 66 to cover this case, and fix the implementation
to honor a discard request on the final partial cluster.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170407013709.18440-1-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add missing error messages for the block driver implementations of
.bdrv_truncate(); drop the generic one from block.c's bdrv_truncate().
Since one of these changes touches a mis-indented block in
block/file-posix.c, this patch fixes that coding style issue along the
way.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170328205129.15138-5-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add an Error parameter to the block drivers' bdrv_truncate() interface.
If a block driver does not set this in case of an error, the generic
bdrv_truncate() implementation will do so.
Where it is obvious, this patch also makes some block drivers set this
value.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170328205129.15138-4-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
