Commit graph

94 commits

Author SHA1 Message Date
Peter Krempa 4b028cbe75 commit: Allow users to request only format driver names in backing file format
Introduce a new flag 'backing-mask-protocol' for the block-commit QMP
command which instructs the internals to use 'raw' instead of the
protocol driver in case when a image is used without a dummy 'raw'
wrapper.

The flag is designed such that it can be always asserted by management
tools even when there isn't any update to backing files.

The flag will be used by libvirt so that the backing images still
reference the proper format even when libvirt will stop using the dummy
raw driver (raw driver with no other config). Libvirt needs this so that
the images stay compatible with older libvirt versions which didn't
expect that a protocol driver name can appear in the backing file format
field.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <2cb46e37093ce793ea1604abc8bbb90f4c8e434b.1701796348.git.pkrempa@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2024-01-26 11:16:58 +01:00
Stefan Hajnoczi 23c983c8f6 block: remove outdated AioContext locking comments
The AioContext lock no longer exists.

There is one noteworthy change:

  - * More specifically, these functions use BDRV_POLL_WHILE(bs), which
  - * requires the caller to be either in the main thread and hold
  - * the BlockdriverState (bs) AioContext lock, or directly in the
  - * home thread that runs the bs AioContext. Calling them from
  - * another thread in another AioContext would cause deadlocks.
  + * More specifically, these functions use BDRV_POLL_WHILE(bs), which requires
  + * the caller to be either in the main thread or directly in the home thread
  + * that runs the bs AioContext. Calling them from another thread in another
  + * AioContext would cause deadlocks.

I am not sure whether deadlocks are still possible. Maybe they have just
moved to the fine-grained locks that have replaced the AioContext. Since
I am not sure if the deadlocks are gone, I have kept the substance
unchanged and just removed mention of the AioContext.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-ID: <20231205182011.1976568-15-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-21 22:49:27 +01:00
Kevin Wolf 1f051dcbdf block: Protect bs->file with graph_lock
Almost all functions that access bs->file already take the graph
lock now. Add locking to the remaining users and finally annotate the
struct field itself as protected by the graph lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-25-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-08 17:56:18 +01:00
Kevin Wolf 79a5586648 block: Add missing GRAPH_RDLOCK annotations
This adds GRAPH_RDLOCK to some driver callbacks that are already called
with the graph lock held, and which will need the annotation because
they access bs->file, but don't have it yet.

This also covers a few callbacks that were not marked GRAPH_RDLOCK
before, but where updating BlockDriver is trivially possible.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-21-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-08 17:56:17 +01:00
Kevin Wolf e2dd273754 block: Introduce bdrv_co_change_backing_file()
bdrv_change_backing_file() is called both inside and outside coroutine
context. This makes it difficult for it to take the graph lock
internally. It also means that driver implementations need to be able to
run outside of coroutines, too. Switch it to the usual model with a
coroutine based implementation and a co_wrapper instead. The new
function is marked GRAPH_RDLOCK.

As the co_wrapper now runs the function in the AioContext of the node
(as it should always have done), this is not GLOBAL_STATE_CODE() any
more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-20-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-08 17:56:17 +01:00
Kevin Wolf 004915a96a block: Protect bs->backing with graph_lock
Almost all functions that access bs->backing already take the graph
lock now. Add locking to the remaining users and finally annotate the
struct field itself as protected by the graph lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-18-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-08 17:56:17 +01:00
Kevin Wolf 067179868e block: Mark bdrv_has_zero_init() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_has_zero_init() need to hold a reader lock for the graph because
it calls bdrv_filter_bs(), which accesses bs->file/backing.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-3-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07 19:14:19 +01:00
Kevin Wolf 221caadcc5 block: Mark bdrv_probe_blocksizes() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_probe_blocksizes() need to hold a reader lock for the graph because
it calls bdrv_filter_bs(), which accesses bs->file/backing.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-2-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-07 19:14:19 +01:00
Kevin Wolf 680e0cc40c block: Protect bs->children with graph_lock
Almost all functions that access the child links already take the graph
lock now. Add locking to the remaining users and finally annotate the
struct field itself as protected by the graph lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-22-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf b59b466071 block: Protect bs->parents with graph_lock
Almost all functions that access the parent link already take the graph
lock now. Add locking to the remaining user in a test case and finally
annotate the struct field itself as protected by the graph lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-21-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf 3574499a1e block: Mark bdrv_get_specific_info() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_get_specific_info() need to hold a reader lock for the graph.
This removes an assume_graph_lock() call in vmdk's implementation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-20-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf 0bb79c97fd qcow2: Mark qcow2_signal_corruption() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
qcow2_signal_corruption() need to hold a reader lock for the graph
because it calls bdrv_get_node_name(), which accesses the parents list
of a node.

For some places, we know that they will hold the lock, but we don't have
the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock()
with a FIXME comment. These places will be removed once everything is
properly annotated.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-15-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf bd131d6705 block: Mark bdrv_amend_options() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_amend_options() need to hold a reader lock for the graph. This
removes an assume_graph_lock() call in crypto's implementation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-14-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf b7cfc7d58e block: Mark bdrv_refresh_filename() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_refresh_filename() need to hold a reader lock for the graph
because it accesses the children list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-11-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf ce433d2942 block: Take graph rdlock in parts of reopen
Reopen isn't easy with respect to locking because many of its functions
need to iterate the graph, some change it, and then you get some drains
in the middle where you can't hold any locks.

Therefore just documents most of the functions to be unlocked, and take
locks internally before accessing the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-9-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf a32e781838 block: Mark bdrv_snapshot_fallback() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_snapshot_fallback() need to hold a reader lock for the graph
because it accesses the children list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-8-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Emanuele Giuseppe Esposito d05ab380db block: Mark drain related functions GRAPH_RDLOCK
Draining recursively traverses the graph, therefore we need to make sure
that also such accesses to the graph are protected by the graph rdlock.

There are 3 different drain callers to consider:
1. drain in the main loop: no issue at all, rdlock is nop.
2. drain in an iothread: rdlock only works in main loop or coroutines,
   so disallow it.
3. drain in a coroutine (regardless of AioContext): the drain mechanism
   takes care of scheduling a BH in the bs->aio_context that will
   then take care of perform the actual draining. This is wrong,
   because as pointed in (2) if bs->aio_context is an iothread then
   rdlock won't work. Therefore change bdrv_co_yield_to_drain to
   schedule the BH in the main loop.

Caller (2) also implies that we need to modify test-bdrv-drain.c to
disallow draining in the iothreads.

For some places, we know that they will hold the lock, but we don't have
the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock()
with a FIXME comment. These places will be removed once everything is
properly annotated.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-6-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf 9def6082cf block: Mark bdrv_add/del_child() and caller GRAPH_WRLOCK
The functions read the parents list in the generic block layer, so we
need to hold the graph lock already there. The BlockDriver
implementations actually modify the graph, so it has to be a writer
lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230911094620.45040-22-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20 17:46:01 +02:00
Kevin Wolf c629b6d223 block: Mark bdrv_child_perm() GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_child_perm() need to hold a reader lock for the graph because
some implementations access the children list of a node.

The callers of bdrv_child_perm() conveniently already hold the lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230911094620.45040-16-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20 17:46:01 +02:00
Kevin Wolf bce73bc25b block: Mark bdrv_get_cumulative_perm() and callers GRAPH_RDLOCK
The function reads the parents list, so it needs to hold the graph lock.

This happens to result in BlockDriver.bdrv_set_perm() to be called with
the graph lock held. For consistency, make it the same for all of the
BlockDriver callbacks for updating permissions and annotate the function
pointers with GRAPH_RDLOCK_PTR.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230911094620.45040-15-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20 17:46:01 +02:00
Kevin Wolf 3804e3cf54 block: Mark bdrv_parent_perms_conflict() and callers GRAPH_RDLOCK
The function reads the parents list, so it needs to hold the graph lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230911094620.45040-14-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20 17:46:01 +02:00
Stefan Hajnoczi 78f8b6d9c8 Block layer patches
- Optimise reqs_lock to make multiqueue actually scale
 - virtio: Drop out of coroutine context in virtio_load()
 - iotests: Fix reference output for some tests after recent changes
 - vpc: Avoid dynamic stack allocation
 - Code cleanup, improved documentation
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Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Optimise reqs_lock to make multiqueue actually scale
- virtio: Drop out of coroutine context in virtio_load()
- iotests: Fix reference output for some tests after recent changes
- vpc: Avoid dynamic stack allocation
- Code cleanup, improved documentation

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# gpg: Signature made Fri 08 Sep 2023 13:10:32 EDT
# gpg:                using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg:                issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin:
  virtio: Drop out of coroutine context in virtio_load()
  vmstate: Mark VMStateInfo.get/put() coroutine_mixed_fn
  block: Make more BlockDriver definitions static
  block/meson.build: Restore alphabetical order of files
  block: Remove unnecessary variable in bdrv_block_device_info
  block: Remove bdrv_query_block_node_info
  vmdk: Clean up bdrv_open_child() return value check
  qemu-img: Update documentation for compressed images
  block: Be more verbose in create fallback
  block/iscsi: Document why we use raw malloc()
  qemu-img: omit errno value in error message
  block: change reqs_lock to QemuMutex
  block: minimize bs->reqs_lock section in tracked_request_end()
  iotests: adapt test output for new qemu_cleanup() behavior
  block/vpc: Avoid dynamic stack allocation

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-09-11 09:11:22 -04:00
Stefan Hajnoczi fa9185fcdf block: change reqs_lock to QemuMutex
CoMutex has poor performance when lock contention is high. The tracked
requests list is accessed frequently and performance suffers in QEMU
multi-queue block layer scenarios.

It is not necessary to use CoMutex for the requests lock. The lock is
always released across coroutine yield operations. It is held for
relatively short periods of time and it is not beneficial to yield when
the lock is held by another coroutine.

Change the lock type from CoMutex to QemuMutex to improve multi-queue
block layer performance. fio randread bs=4k iodepth=64 with 4 IOThreads
handling a virtio-blk device with 8 virtqueues improves from 254k to
517k IOPS (+203%). Full benchmark results and configuration details are
available here:
980c40845d

In the future we may wish to introduce thread-local tracked requests
lists to avoid lock contention completely. That would be much more
involved though.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230808155852.2745350-3-stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-08 17:03:09 +02:00
Michael Tokarev a1a62ced51 include/: spelling fixes
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2023-09-08 13:08:52 +03:00
Stefan Hajnoczi 2a0d7cb6b7 block: remove bdrv_co_io_plug() API
No block driver implements .bdrv_co_io_plug() anymore. Get rid of the
function pointers.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20230530180959.1108766-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-06-01 08:59:24 -04:00
Stefan Hajnoczi ab61335025 block: drain from main loop thread in bdrv_co_yield_to_drain()
For simplicity, always run BlockDevOps .drained_begin/end/poll()
callbacks in the main loop thread. This makes it easier to implement the
callbacks and avoids extra locks.

Move the function pointer declarations from the I/O Code section to the
Global State section for BlockDevOps, BdrvChildClass, and BlockDriver.

Narrow IO_OR_GS_CODE() to GLOBAL_STATE_CODE() where appropriate.

The test-bdrv-drain test case calls bdrv_drain() from an IOThread. This
is now only allowed from coroutine context, so update the test case to
run in a coroutine.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-11-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
Kevin Wolf 4db7ba3b87 block: Call .bdrv_co_create(_opts) unlocked
These are functions that modify the graph, so they must be able to take
a writer lock. This is impossible if they already hold the reader lock.
If they need a reader lock for some of their operations, they should
take it internally.

Many of them go through blk_*(), which will always take the lock itself.
Direct calls of bdrv_*() need to take the reader lock. Note that while
locking for bdrv_co_*() calls is checked by TSA, this is not the case
for the mixed_coroutine_fns bdrv_*(). Holding the lock is still required
when they are called from coroutine context like here!

This effectively reverts 4ec8df0183, but adds some internal locking
instead.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-2-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19 19:12:12 +02:00
Sam Li 4751d09adc block: introduce zone append write for zoned devices
A zone append command is a write operation that specifies the first
logical block of a zone as the write position. When writing to a zoned
block device using zone append, the byte offset of the call may point at
any position within the zone to which the data is being appended. Upon
completion the device will respond with the position where the data has
been written in the zone.

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20230508051510.177850-3-faithilikerun@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-05-15 08:18:10 -04:00
Sam Li a3c41f06d5 file-posix: add tracking of the zone write pointers
Since Linux doesn't have a user API to issue zone append operations to
zoned devices from user space, the file-posix driver is modified to add
zone append emulation using regular writes. To do this, the file-posix
driver tracks the wp location of all zones of the device. It uses an
array of uint64_t. The most significant bit of each wp location indicates
if the zone type is conventional zones.

The zones wp can be changed due to the following operations issued:
- zone reset: change the wp to the start offset of that zone
- zone finish: change to the end location of that zone
- write to a zone
- zone append

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Message-id: 20230508051510.177850-2-faithilikerun@gmail.com
[Fix errno propagation from handle_aiocb_zone_mgmt()
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-05-15 08:17:55 -04:00
Sam Li 774c726ceb block: add zoned BlockDriver check to block layer
Putting zoned/non-zoned BlockDrivers on top of each other is not
allowed.

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20230508045533.175575-6-faithilikerun@gmail.com
Message-id: 20230324090605.28361-6-faithilikerun@gmail.com
[Adjust commit message prefix as suggested by Philippe Mathieu-Daudé
<philmd@linaro.org> and clarify that the check is about zoned
BlockDrivers.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-05-15 08:17:03 -04:00
Sam Li 6d43eaa396 block/block-backend: add block layer APIs resembling Linux ZonedBlockDevice ioctls
Add zoned device option to host_device BlockDriver. It will be presented only
for zoned host block devices. By adding zone management operations to the
host_block_device BlockDriver, users can use the new block layer APIs
including Report Zone and four zone management operations
(open, close, finish, reset, reset_all).

Qemu-io uses the new APIs to perform zoned storage commands of the device:
zone_report(zrp), zone_open(zo), zone_close(zc), zone_reset(zrs),
zone_finish(zf).

For example, to test zone_report, use following command:
$ ./build/qemu-io --image-opts -n driver=host_device, filename=/dev/nullb0
-c "zrp offset nr_zones"

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20230508045533.175575-4-faithilikerun@gmail.com
Message-id: 20230324090605.28361-4-faithilikerun@gmail.com
[Adjust commit message prefix as suggested by Philippe Mathieu-Daudé
<philmd@linaro.org> and remove spurious ret = -errno in
raw_co_zone_mgmt().
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-05-15 08:17:03 -04:00
Sam Li a735b56e49 block/file-posix: introduce helper functions for sysfs attributes
Use get_sysfs_str_val() to get the string value of device
zoned model. Then get_sysfs_zoned_model() can convert it to
BlockZoneModel type of QEMU.

Use get_sysfs_long_val() to get the long value of zoned device
information.

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20230508045533.175575-3-faithilikerun@gmail.com
Message-id: 20230324090605.28361-3-faithilikerun@gmail.com
[Adjust commit message prefix as suggested by Philippe Mathieu-Daudé
<philmd@linaro.org>.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-05-15 08:17:03 -04:00
Kevin Wolf e19b157f3c block: Mark bdrv_refresh_limits() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_refresh_limits() need to hold a reader lock for the graph because
it accesses the children list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-21-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:54 +02:00
Kevin Wolf 533c6e4ee8 block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_recurse_can_replace() need to hold a reader lock for the graph
because it accesses the children list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-20-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:54 +02:00
Emanuele Giuseppe Esposito 840428a266 block: Mark BlockDriver callbacks for amend job GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of amend
callbacks in BlockDriver need to hold a reader lock for the graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-17-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:54 +02:00
Emanuele Giuseppe Esposito cb2bfaa450 block: Mark bdrv_co_debug_event() GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_debug_event() need to hold a reader lock for the graph.

Unfortunately we cannot use a co_wrapper_bdrv_rdlock (i.e. make the
coroutine wrapper a no_coroutine_fn), because the function is called
(using the BLKDBG_EVENT macro) by mixed functions that run both in
coroutine and non-coroutine context (for example many of the functions
in qcow2-cluster.c and qcow2-refcount.c).

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-16-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:54 +02:00
Emanuele Giuseppe Esposito a00e70c012 block: Mark bdrv_co_get_info() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_get_info() need to hold a reader lock for the graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-15-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:54 +02:00
Emanuele Giuseppe Esposito de335638a3 block: Mark bdrv_co_get_allocated_file_size() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_get_allocated_file_size() need to hold a reader lock for the
graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230504115750.54437-14-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:54 +02:00
Kevin Wolf 1a30b0f5d7 block: .bdrv_open is non-coroutine and unlocked
Drivers were a bit confused about whether .bdrv_open can run in a
coroutine and whether or not it holds a graph lock.

It cannot keep a graph lock from the caller across the whole function
because it both changes the graph (requires a writer lock) and does I/O
(requires a reader lock). Therefore, it should take these locks
internally as needed.

The functions used to be called in coroutine context during image
creation. This was buggy for other reasons, and as of commit 32192301,
all block drivers go through no_co_wrappers. So it is not called in
coroutine context any more.

Fix qcow2 and qed to work with the correct assumptions: The graph lock
needs to be taken internally instead of just assuming it's already
there, and the coroutine path is dead code that can be removed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-9-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:53 +02:00
Wilfred Mallawa 04ae220dbc include/block: fixup typos
Fixup a few minor typos

Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Message-Id: <20230313003744.55476-1-wilfred.mallawa@opensource.wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-25 13:17:28 +02:00
Paolo Bonzini 8c6f27e7d8 block: remove has_variable_length from BlockDriver
Fill in the field in BlockLimits directly for host devices, and
copy it from there for the raw format.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20230407153303.391121-5-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-11 16:39:01 +02:00
Paolo Bonzini 160a29e2f8 block: move has_variable_length to BlockLimits
At the protocol level, has_variable_length only needs to be true in the
very special case of host CD-ROM drives, so that they do not need an
explicit monitor command to read the new size when a disc is loaded
in the tray.

However, at the format level has_variable_length has to be true for all
raw blockdevs and for all filters, even though in practice the length
depends on the underlying file and thus will not change except in the
case of host CD-ROM drives.

As a first step towards computing an accurate value of has_variable_length,
add the value into the BlockLimits structure and initialize the field
from the BlockDriver.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20230407153303.391121-2-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-11 16:38:34 +02:00
Kevin Wolf 8ab8140a04 block: Mark bdrv_co_refresh_total_sectors() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_refresh_total_sectors() need to hold a reader lock for the
graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-24-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:33 +01:00
Kevin Wolf 167f748d8c block: Mark bdrv_*_dirty_bitmap() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_*_dirty_bitmap() need to hold a reader lock for the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-23-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:32 +01:00
Kevin Wolf 48aef79440 block: Mark bdrv_co_delete_file() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_delete_file() need to hold a reader lock for the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-22-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:30 +01:00
Kevin Wolf d9249c253c block: Mark bdrv_(un)register_buf() GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_register_buf() and bdrv_unregister_buf() need to hold a reader lock
for the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-21-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:29 +01:00
Kevin Wolf 79a292e5ec block: Mark bdrv_co_eject/lock_medium() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_eject() and bdrv_co_lock_medium() need to hold a reader lock for
the graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-20-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:26 +01:00
Emanuele Giuseppe Esposito c73ff92c9d block: Mark bdrv_co_is_inserted() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_is_inserted() need to hold a reader lock for the graph.

blk_is_inserted() is done as a co_wrapper_mixed_bdrv_rdlock (unlike most
other blk_* functions) because it is called a lot from other blk_co_*()
functions that already hold the lock. These calls go through
blk_is_available(), which becomes a co_wrapper_mixed_bdrv_rdlock, too,
for the same reason.

Functions that run in a coroutine and can call bdrv_co_is_available()
directly are changed to do so, which results in better TSA coverage.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-19-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:25 +01:00
Kevin Wolf c382706925 block: Mark bdrv_co_io_(un)plug() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_io_plug() and bdrv_co_io_unplug() need to hold a reader lock for
the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-18-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:24 +01:00
Kevin Wolf 4ec8df0183 block: Mark bdrv_co_create() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_create() need to hold a reader lock for the graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-17-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:23 +01:00