Commit Graph

678 Commits

Author SHA1 Message Date
Vladimir Sementsov-Ogievskiy 8164102ffe blockdev: blockdev_mark_auto_del: drop usage of bs->job
We are going to remove bs->job pointer. Drop it's usage in
blockdev_mark_auto_del: instead of looking at bs->job let's check all
jobs for references to bs.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-18 16:41:10 +02:00
Max Reitz a2bb6f8c92 blockdev: Overlays are not snapshots
There are error messages which refer to an overlay node as the snapshot.
That is wrong, those are two different things.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20190603202236.1342-3-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-06-14 14:16:57 +02:00
John Snow d81e1efbea blockdev-backup: don't check aio_context too early
in blockdev_backup_prepare, we check to make sure that the target is
associated with a compatible aio context. However, do_blockdev_backup is
called later and has some logic to move the target to a compatible
aio_context. The transaction version will fail certain commands
needlessly early as a result.

Allow blockdev_backup_prepare to simply call do_blockdev_backup, which
will ultimately decide if the contexts are compatible or not.

Note: the transaction version has always disallowed this operation since
its initial commit bd8baecd (2014), whereas the version of
qmp_blockdev_backup at the time, from commit c29c1dd312, tried to
enforce the aio_context switch instead. It's not clear, and I can't see
from the mailing list archives at the time, why the two functions take a
different approach. It wasn't until later in efd7556708 (2016) that the
standalone version tried to determine if it could set the context or
not.

Reported-by: aihua liang <aliang@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1683498
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20190523170643.20794-2-jsnow@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-06-14 14:16:57 +02:00
Kevin Wolf 8ed7d42fb5 blockdev: Use bdrv_try_set_aio_context() for monitor commands
Monitor commands can handle errors, so they can easily be converted to
using the safer bdrv_try_set_aio_context() function.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04 15:22:22 +02:00
Kevin Wolf d861ab3acf block: Add BlockBackend.ctx
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>
2019-06-04 15:22:22 +02:00
John Snow 4da26f138d blockdev: fix missed target unref for drive-backup
If the bitmap can't be used for whatever reason, we skip putting down
the reference. Fix that.

In practice, this means that if you attempt to gracefully exit QEMU
after a backup command being rejected, bdrv_close_all will fail and
tell you some unpleasant things via assert().

Reported-by: aihua liang <aliang@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1703916
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04 15:20:41 +02:00
Peter Maydell 62f6849e7a Pull request
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE+ber27ys35W+dsvQfe+BBqr8OQ4FAlztyykACgkQfe+BBqr8
 OQ4EaA//QQVDpIBRcMN+LeKWeEs8VSLziPUrZuFvuhMEEnjnaU6gbKq8G8xbFQ62
 JIHg0DBGhTt8ymE9Ay6O/cooR8F0z+XyfDr7UlpI7JL/Uwl7JguGKQrWUYBRMqCv
 Q2cLaWStLkfdkuW7Y3WRc16VEnIlizDxjRzfjE2ESYpuzD2fFsBY3KZbgbJwYwZw
 SujWUQ3MdsNdw5kDmerlrDUy7r/eyl2cLXyIt6ClHNoqq392oGMoUn4XbsaLnCWE
 H5s46qm33eXtvBHqxVGoOMAli5FwCnhwF+H3xg93jIG6vC/RXQYCIhlEmEwKyrU2
 g2DWWe/8+9b0iX+zTIcAPTcn1pmjVivGRorOurP0AtMtjV/8PvV+hAQQeSg2ARB3
 rLpXaEphD4WTwu7mYlZ5kX0qvX2SftaMU08k1IgR3mfo8Z3X9znVoFIv8HLlHuy+
 OhCmwT5OWYw4mNABTXeBMH/Dcs9EcU4+T/KhAGLReHo18CSyjeT2xsT+XCsETagF
 KlAP88dP0EdJ9Oiccyb8as22u7ygKWIiDYPplBdb4SkKg/koQnYGDjeDAzB2vXS3
 cGVhGJD2DBbcePA8iaCfWzsSCDOTBFQLa45uhPD3DnkAJylhecSsiDQP+IrLslK3
 h/8v9e8MAlHMgrueSnS7foMDI9rdrTNsChuNCJWOOaUI/ZWnXFg=
 =kCrN
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

Pull request

# gpg: Signature made Wed 29 May 2019 00:58:33 BST
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request:
  iotests: test external snapshot with bitmap copying
  qapi: support external bitmaps in block-dirty-bitmap-merge
  migration/dirty-bitmaps: change bitmap enumeration method

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-05-30 12:10:27 +01:00
Vladimir Sementsov-Ogievskiy eff0829b07 qapi: support external bitmaps in block-dirty-bitmap-merge
Add new optional parameter making possible to merge bitmaps from
different nodes. It is needed to maintain external snapshots during
incremental backup chain history.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190517152111.206494-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-05-28 19:33:31 -04:00
John Snow a2d665c1bc blockdev: loosen restrictions on drive-backup source node
We mandate that the source node must be a root node; but there's no reason
I am aware of that it needs to be restricted to such. In some cases, we need
to make sure that there's a medium present, but in the general case we can
allow the backup job itself to do the graph checking.

This patch helps improve the error message when you try to backup from
the same node more than once, which is reflected in the change to test
056.

For backups with bitmaps, it will also show a better error message that
the bitmap is in use instead of giving you something cryptic like "need
a root node."

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1707303
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20190521210053.8864-1-jsnow@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-05-28 20:30:55 +02:00
Markus Armbruster cdcd436120 blockdev: Make -drive format=help print to stdout
Command line help explicitly requested by the user should be printed
to stdout, not stderr.  We do elsewhere.  Adjust -drive to match: use
qemu_printf() instead of error_printf().  Plain printf() would be
wrong because we need to print to the current monitor for "drive_add
... format=help".

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190417190641.26814-13-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Max Reitz 74ce9e466a blockdev: Check @replaces in blockdev_mirror_common
There is no reason why the constraints we put on @replaces should be
limited to drive-mirror.  Therefore, move the sanity checks from
qmp_drive_mirror() to blockdev_mirror_common() so they apply to
blockdev-mirror as well.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-19 15:50:20 +01:00
Peter Maydell 523a2a42c3 Pull request
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE+ber27ys35W+dsvQfe+BBqr8OQ4FAlyIFSwACgkQfe+BBqr8
 OQ7wghAAm16eCEr57oTO7QXR3y8uVFsKqXBn9cNH6nbrFp2PUQSglwMDKBls1Z5m
 olF23X/JaqSlSmkL9BBuzDZ6Up+kkHKuxPq4/5RKXfiDI0pr3R0eqts0COAlaN9q
 Bew3ipj99m8gzMi2093AW4+Ob0N3658fuDTGLe1M1Uoy7CEg1QJ7rVOBBEui7vIl
 RbZ8l/Zmb4ldNpB3lnE4Nh9ue8fy0RAj3Nai161nCnNeXNF/VzD3Ye8bojSBbnux
 PIMX6/RWmykX4feIf9QP8apDpxX4HkyuPq5EdwT9PD8PwdyXPAXZtsYUNCuNtQuk
 n5VKFVgFYgqUclBeVHmrMYPU4K4iCFQp4/Fua7wzPEC0iG05NiiDv91oVkEJCp3L
 ManHeuGfNLCcXaIntKZhuJl1cK8yMM3yDww6/pPTehrPjcyvKa0NOqhQBExektcD
 R6q7maJRzFaxSxdcs+Zzuog9zESvH1mlJxQCKzeYhAP0kkxInyTELE/Vbx37xuqR
 RFfZYyVQ6x87Q/sxHx4EMiV97WUM8elZOQdSEC/okt5WUUNpgIu0WF9nSQ1VKZ8C
 CZmv5xh9ogfwvB/kOm6IVwNkLvVagJQcLwddORI5LLXLbSIUcuwVSuyMp/7iDtQ/
 hnHkGs2mIJ2JUYbSSNsSJNs6oTurn8eTFCeGoYKJgd9l4QxaThU=
 =ekU+
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

Pull request

# gpg: Signature made Tue 12 Mar 2019 20:23:08 GMT
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request: (22 commits)
  tests/qemu-iotests: add bitmap resize test 246
  block/qcow2-bitmap: Allow resizes with persistent bitmaps
  block/qcow2-bitmap: Don't check size for IN_USE bitmap
  docs/interop/qcow2: Improve bitmap flag in_use specification
  bitmaps: Fix typo in function name
  block/dirty-bitmaps: implement inconsistent bit
  block/dirty-bitmaps: disallow busy bitmaps as merge source
  block/dirty-bitmaps: prohibit removing readonly bitmaps
  block/dirty-bitmaps: prohibit readonly bitmaps for backups
  block/dirty-bitmaps: add block_dirty_bitmap_check function
  block/dirty-bitmap: add inconsistent status
  block/dirty-bitmaps: add inconsistent bit
  iotests: add busy/recording bit test to 124
  blockdev: remove unused paio parameter documentation
  block/dirty-bitmaps: move comment block
  block/dirty-bitmaps: unify qmp_locked and user_locked calls
  block/dirty-bitmap: explicitly lock bitmaps with successors
  nbd: change error checking order for bitmaps
  block/dirty-bitmap: change semantics of enabled predicate
  block/dirty-bitmap: remove set/reset assertions against enabled bit
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	tests/qemu-iotests/group
2019-03-13 17:30:34 +00:00
Alberto Garcia 1479c730c7 block: Add an 'x-blockdev-reopen' QMP command
This command allows reopening an arbitrary BlockDriverState with a
new set of options. Some options (e.g node-name) cannot be changed
and some block drivers don't allow reopening, but otherwise this
command is modelled after 'blockdev-add' and the state of the reopened
BlockDriverState should generally be the same as if it had just been
added by 'blockdev-add' with the same set of options.

One notable exception is the 'backing' option: 'x-blockdev-reopen'
requires that it is always present unless the BlockDriverState in
question doesn't have a current or default backing file.

This command allows reconfiguring the graph by using the appropriate
options to change the children of a node. At the moment it's possible
to change a backing file by setting the 'backing' option to the name
of the new node, but it should also be possible to add a similar
functionality to other block drivers (e.g. Quorum, blkverify).

Although the API is unlikely to change, this command is marked
experimental for the time being so there's room to see if the
semantics need changes.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-12 20:30:14 +01:00
Vladimir Sementsov-Ogievskiy cb8aac3783 qapi: drop x- from x-block-latency-histogram-set
Drop x- and x_ prefixes for latency histograms and update version to
4.0

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-12 20:30:08 +01:00
Eric Blake 796a3798ab bitmaps: Fix typo in function name
Commit a88b179f introduced the ability to set and query bitmap
persistence, but with an atypical spelling.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20190308205845.25734-1-eblake@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:05:49 -04:00
John Snow c3edf13cd1 block/dirty-bitmaps: prohibit removing readonly bitmaps
Remove is an inherently RW operation, so this will fail anyway, but
we can fail it very quickly instead of trying and failing, so do so.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190301191545.8728-6-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:05:49 -04:00
John Snow a54a0c113b block/dirty-bitmaps: prohibit readonly bitmaps for backups
drive and blockdev backup cannot use readonly bitmaps, because the
sync=incremental mechanism actually edits the bitmaps on success.

If you really want to do this operation, use a copied bitmap.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190301191545.8728-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:05:49 -04:00
John Snow 3ae96d6684 block/dirty-bitmaps: add block_dirty_bitmap_check function
Instead of checking against busy, inconsistent, or read only directly,
use a check function with permissions bits that let us streamline the
checks without reproducing them in many places.

Included in this patch are permissions changes that simply add the
inconsistent check to existing permissions call spots, without
addressing existing bugs.

In general, this means that busy+readonly checks become BDRV_BITMAP_DEFAULT,
which checks against all three conditions. busy-only checks become
BDRV_BITMAP_ALLOW_RO.

Notably, remove allows inconsistent bitmaps, so it doesn't follow the pattern.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190301191545.8728-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:05:49 -04:00
John Snow 2f158ca7b6 blockdev: remove unused paio parameter documentation
This field isn't present anymore.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190223000614.13894-10-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:05:48 -04:00
John Snow 27a1b301a4 block/dirty-bitmaps: unify qmp_locked and user_locked calls
These mean the same thing now. Unify them and rename the merged call
bdrv_dirty_bitmap_busy to indicate semantically what we are describing,
as well as help disambiguate from the various _locked and _unlocked
versions of bitmap helpers that refer to mutex locks.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190223000614.13894-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:05:48 -04:00
Vladimir Sementsov-Ogievskiy af0a226504 qapi: move to QOM path for x-block-latency-histogram-set
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-12 14:26:49 +01:00
Andrey Shinkevich 9ac404c523 block: iterate_format with account of whitelisting
bdrv_iterate_format (which is currently only used for printing out the
formats supported by the block layer) doesn't take format whitelisting
into account.

This creates a problem for tests: they enumerate supported formats to
decide which tests to enable, but then discover that QEMU doesn't let
them actually use some of those formats.

To avoid that, exclude formats that are not whitelisted from
enumeration, if whitelisting is in use.  Since we have separate
whitelists for r/w and r/o, take this a parameter to
bdrv_iterate_format, and print two lists of supported formats (r/w and
r/o) in main qemu.

Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-08 12:26:45 +01:00
Max Reitz f30c66ba6e block: Use bdrv_refresh_filename() to pull
Before this patch, bdrv_refresh_filename() is used in a pushing manner:
Whenever the BDS graph is modified, the parents of the modified edges
are supposed to be updated (recursively upwards).  However, that is
nonviable, considering that we want child changes not to concern
parents.

Also, in the long run we want a pull model anyway: Here, we would have a
bdrv_filename() function which returns a BDS's filename, freshly
constructed.

This patch is an intermediate step.  It adds bdrv_refresh_filename()
calls before every place a BDS.filename value is used.  The only
exceptions are protocol drivers that use their own filename, which
clearly would not profit from refreshing that filename before.

Also, bdrv_get_encrypted_filename() is removed along the way (as a user
of BDS.filename), since it is completely unused.

In turn, all of the calls to bdrv_refresh_filename() before this patch
are removed, because we no longer have to call this function on graph
changes.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190201192935.18394-2-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-02-25 15:11:25 +01:00
John Snow 0a6c86d024 blockdev: acquire aio_context for bitmap add/remove
When bitmaps are persistent, they may incur a disk read or write when bitmaps
are added or removed. For configurations like virtio-dataplane, failing to
acquire this lock will abort QEMU when disk IO occurs.

We used to acquire aio_context as part of the bitmap lookup, so re-introduce
the lock for just the cases that have an IO penalty. Commit 2119882c removed
these locks, and I failed to notice this when we committed fd5ae4cc, so this
has been broken since persistent bitmaps were introduced.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1672010
Reported-By: Aihua Liang <aliang@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20190218233154.19303-1-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-02-19 17:49:43 -05:00
Vladimir Sementsov-Ogievskiy 5d3b4e9946 qapi: add x-debug-query-block-graph
Add a new command, returning block nodes (and their users) graph.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20181221170909.25584-2-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-01-31 00:38:19 +01:00
John Snow 0e2b7f0983 block: remove 'x' prefix from experimental bitmap APIs
The 'x' prefix was added because I was uncertain of the direction we'd
take for the libvirt API. With the general approach solidified, I feel
comfortable committing to this API for 4.0.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20181221093529.23855-5-jsnow@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-01-14 10:09:46 -06:00
John Snow 360d4e4e9a blockdev: n-ary bitmap merge
Especially outside of transactions, it is helpful to provide
all-or-nothing semantics for bitmap merges. This facilitates
the coalescing of multiple bitmaps into a single target for
the "checkpoint" interpretation when assembling bitmaps that
represent arbitrary points in time from component bitmaps.

This is an incompatible change from the preliminary version
of the API.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20181221093529.23855-4-jsnow@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-01-14 10:09:46 -06:00
John Snow f4de0f8c40 blockdev: abort transactions in reverse order
Presently, we abort transactions in the same order they were processed in.
Bitmap commands, though, attempt to restore backup data structures on abort.

That's not valid, they need to be aborted in reverse chronological order.

Replace the QSIMPLEQ data structure with a QTAILQ one, so we can iterate
in reverse for the abort phase of the transaction.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20181221093529.23855-2-jsnow@redhat.com>
[eblake: rebase]
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-01-14 10:08:47 -06:00
Paolo Bonzini b58deb344d qemu/queue.h: leave head structs anonymous unless necessary
Most list head structs need not be given a name.  In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed.  In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct.  So clean up everything, not giving a
name except in the rare case where it is necessary.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:55 +01:00
Paolo Bonzini 70537ed515 qemu/queue.h: do not access tqe_prev directly
Use the QTAILQ_IN_USE macro instead, it does the same thing but the next
patch will change it to a different definition.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:54 +01:00
Markus Armbruster b2322003b6 error: Remove NULL checks on error_propagate() calls
Patch created mechanically by rerunning:

  $  spatch --sp-file scripts/coccinelle/error_propagate_null.cocci \
            --macro-file scripts/cocci-macro-file.h \
            --dir . --in-place

Whitespace tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181213173113.11211-1-armbru@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2018-12-18 14:57:48 +01:00
Alberto Garcia 1b57774f79 block: Use bdrv_reopen_set_read_only() in external_snapshot_commit()
This patch replaces the bdrv_reopen() call that set and remove the
BDRV_O_RDWR flag with the new bdrv_reopen_set_read_only() function.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Alberto Garcia 051a60f6a3 block: Use bdrv_reopen_set_read_only() in qmp_change_backing_file()
This patch replaces the bdrv_reopen() calls that set and remove the
BDRV_O_RDWR flag with the new bdrv_reopen_set_read_only() function.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Peter Maydell d52e1a0e96 blockdev: Consistently use snapshot_node_name in external_snapshot_prepare()
In the function external_snapshot_prepare() we have a
BlockdevSnapshotSync struct, which has the usual combination
of has_snapshot_node_name and snapshot_node_name fields for an
optional field. We set up a local variable
        const char *snapshot_node_name =
            s->has_snapshot_node_name ? s->snapshot_node_name : NULL;

and then mostly use "if (!snapshot_node_name)" for checking
whether we have a snapshot node name. The exception is that in
one place we check s->has_snapshot_node_name instead. This
confuses Coverity (CID 1396473), which thinks it might be
possible to get here with s->has_snapshot_node_name true but
snapshot_node_name NULL, and warns that the call to
qdict_put_str() will segfault in that case.

Make the code consistent and unconfuse Coverity by using
the same check for this conditional that we do in the rest
of the surrounding code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-11-12 17:46:57 +01:00
zhenwei pi 63d5341f85 blockdev: handle error on block latency histogram set error
Function block_latency_histogram_set may return error, but qapi ignore this.
This can be reproduced easily by qmp command:
virsh qemu-monitor-command INSTANCE '{"execute":"x-block-latency-histogram-set",
"arguments":{"device":"drive-virtio-disk1","boundaries":[10,200,40]}}'
In fact this command does not work, but we still get success result.

qmp_x_block_latency_histogram_set is a batch setting API, report error ASAP.

Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-11-12 17:46:57 +01:00
Kevin Wolf 9384a444f6 block: Make auto-read-only=on default for -drive
While we want machine interfaces like -blockdev and QMP blockdev-add to
add as little auto-detection as possible so that management tools are
explicit about their needs, -drive is a convenience option for human
users. Enabling auto-read-only=on by default there enables users to use
read-only images for read-only guest devices without having to specify
read-only=on explicitly. If they try to attach the image to a read-write
device, they will still get an error message.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-11-05 15:09:55 +01:00
Kevin Wolf e35bdc123a block: Add auto-read-only option
If a management application builds the block graph node by node, the
protocol layer doesn't inherit its read-only option from the format
layer any more, so it must be set explicitly.

Backing files should work on read-only storage, but at the same time, a
block job like commit should be able to reopen them read-write if they
are on read-write storage. However, without option inheritance, reopen
only changes the read-only option for the root node (typically the
format layer), but not the protocol layer, so reopening fails (the
format layer wants to get write permissions, but the protocol layer is
still read-only).

A simple workaround for the problem in the management tool would be to
open the protocol layer always read-write and to make only the format
layer read-only for backing files. However, sometimes the file is
actually stored on read-only storage and we don't know whether the image
can be opened read-write (for example, for NBD it depends on the server
we're trying to connect to). This adds an option that makes QEMU try to
open the image read-write, but allows it to degrade to a read-only mode
without returning an error.

The documentation for this option is consciously phrased in a way that
allows QEMU to switch to a better model eventually: Instead of trying
when the image is first opened, making the read-only flag dynamic and
changing it automatically whenever the first BLK_PERM_WRITE user is
attached or the last one is detached would be much more useful
behaviour.

Unfortunately, this more useful behaviour is also a lot harder to
implement, and libvirt needs a solution now before it can switch to
-blockdev, so let's start with this easier approach for now.

Instead of adding a new auto-read-only option, turning the existing
read-only into an enum (with a bool alternate for compatibility) was
considered, but it complicated the implementation to the point that it
didn't seem to be worth it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-11-05 15:09:55 +01:00
John Snow b27a6b8b32 block/backup: prohibit backup from using in use bitmaps
If the bitmap is frozen, we shouldn't touch it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20181002230218.13949-6-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:16 -04:00
John Snow b053bb5573 block/dirty-bitmaps: prohibit enable/disable on locked/frozen bitmaps
We're not being consistent about this. If it's in use by an operation,
the user should not be able to change the behavior of that bitmap.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20181002230218.13949-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:16 -04:00
John Snow 0be37c9e19 block/dirty-bitmaps: allow clear on disabled bitmaps
Similarly to merge, it's OK to allow clear operations on disabled
bitmaps, as this condition only means that they are not recording
new writes. We are free to clear it if the user requests it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20181002230218.13949-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:16 -04:00
John Snow 993edc0ce0 block/dirty-bitmaps: add user_locked status checker
Instead of both frozen and qmp_locked checks, wrap it into one check.
frozen implies the bitmap is split in two (for backup), and shouldn't
be modified. qmp_locked implies it's being used by another operation,
like being exported over NBD. In both cases it means we shouldn't allow
the user to modify it in any meaningful way.

Replace any usages where we check both frozen and qmp_locked with the
new check.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20181002230218.13949-2-jsnow@redhat.com
[w/edits Suggested-By: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]
Signed-off-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:16 -04:00
Vladimir Sementsov-Ogievskiy 6fd2e40789 qapi: add transaction support for x-block-dirty-bitmap-merge
New action is like clean action: do the whole thing in .prepare and
undo in .abort. This behavior for bitmap-changing actions is needed
because backup job actions use bitmap in .prepare.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:15 -04:00
Vladimir Sementsov-Ogievskiy 5c4cf8b294 blockdev: rename block-dirty-bitmap-clear transaction handlers
Rename block-dirty-bitmap-clear transaction handlers to reuse them for
x-block-dirty-bitmap-merge transaction in the following patch.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:15 -04:00
Vladimir Sementsov-Ogievskiy fa000f2f9f dirty-bitmap: make it possible to restore bitmap after merge
Add backup parameter to bdrv_merge_dirty_bitmap() to be used then with
bdrv_restore_dirty_bitmap() if it needed to restore the bitmap after
merge operation.

This is needed to implement bitmap merge transaction action in further
commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:15 -04:00
Vladimir Sementsov-Ogievskiy 56bd662497 dirty-bitmap: rename bdrv_undo_clear_dirty_bitmap
Use more generic names to reuse the function for bitmap merge in the
following commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:14 -04:00
Vladimir Sementsov-Ogievskiy 06bf50068a dirty-bitmap: switch assert-fails to errors in bdrv_merge_dirty_bitmap
Move checks from qmp_x_block_dirty_bitmap_merge() to
bdrv_merge_dirty_bitmap(), to share them with dirty bitmap merge
transaction action in future commit.

Note: for now, only qmp_x_block_dirty_bitmap_merge() calls
bdrv_merge_dirty_bitmap().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:14 -04:00
John Snow 945c1ee0cb blockdev-backup: add bitmap argument
It is only an oversight that we don't allow incremental backup with
blockdev-backup. Add the bitmap argument which enables this.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20180830211605.13683-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2018-10-29 16:23:14 -04:00
Markus Armbruster c4f26c9f37 blockdev: Convert drive_new() to Error
Calling error_report() from within a function that takes an Error **
argument is suspicious.  drive_new() calls error_report() even though
it can run within drive_init_func(), which takes an Error ** argument.
drive_init_func()'s caller main(), via qemu_opts_foreach(), is fine
with it, but clean it up anyway:

* Convert drive_new() to Error

* Update add_init_drive() to report the error received from
  drive_new()

* Make main() pass &error_fatal through qemu_opts_foreach(),
  drive_init_func() to drive_new()

* Make default_drive() pass &error_abort through qemu_opts_foreach(),
  drive_init_func() to drive_new()

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181017082702.5581-34-armbru@redhat.com>
2018-10-19 14:51:34 +02:00
Kevin Wolf 3c605f4074 commit: Add top-node/base-node options
The block-commit QMP command required specifying the top and base nodes
of the commit jobs using the file name of that node. While this works
in simple cases (local files with absolute paths), the file names
generated for more complicated setups can be hard to predict.

The block-commit command has more problems than just this, so we want to
replace it altogether in the long run, but libvirt needs a reliable way
to address nodes now. So we don't want to wait for a new, cleaner
command, but just add the minimal thing needed right now.

This adds two new options top-node and base-node to the command, which
allow specifying node names instead. They are mutually exclusive with
the old options.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-09-25 15:50:15 +02:00
John Snow 66da04ddd3 blockdev: document transactional shortcomings
Presently only the backup job really guarantees what one would consider
transactional semantics. To guard against someone helpfully adding them
in the future, document that there are shortcomings in the model that
would need to be audited at that time.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20180906130225.5118-17-jsnow@redhat.com
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-09-25 15:31:15 +02:00