Commit Graph

1488 Commits

Author SHA1 Message Date
Paolo Bonzini
17362398ee block: use bdrv_co_debug_event in coroutine context
bdrv_co_debug_event was recently introduced, with bdrv_debug_event
becoming a wrapper for use in unknown context.  Because most of the
time bdrv_debug_event is used on a BdrvChild via the wrapper macro
BLKDBG_EVENT, introduce a similar macro BLKDBG_CO_EVENT that calls
bdrv_co_debug_event, and switch whenever possible.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20230601115145.196465-13-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-06-28 09:46:34 +02:00
Kevin Wolf
31b2ddfea3 graph-lock: Unlock the AioContext while polling
If the caller keeps the AioContext lock for a block node in an iothread,
polling in bdrv_graph_wrlock() deadlocks if the condition isn't
fulfilled immediately.

Now that all callers make sure to actually have the AioContext locked
when they call bdrv_replace_child_noperm() like they should, we can
change bdrv_graph_wrlock() to take a BlockDriverState whose AioContext
lock the caller holds (NULL if it doesn't) and unlock it temporarily
while polling.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230605085711.21261-11-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-06-28 08:46:23 +02:00
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
076682885d block/linux-aio: convert to blk_io_plug_call() API
Stop using the .bdrv_co_io_plug() API because it is not multi-queue
block layer friendly. Use the new blk_io_plug_call() API to batch I/O
submission instead.

Note that a dev_max_batch check is dropped in laio_io_unplug() because
the semantics of unplug_fn() are different from .bdrv_co_unplug():
1. unplug_fn() is only called when the last blk_io_unplug() call occurs,
   not every time blk_io_unplug() is called.
2. unplug_fn() is per-thread, not per-BlockDriverState, so there is no
   way to get per-BlockDriverState fields like dev_max_batch.

Therefore this condition cannot be moved to laio_unplug_fn(). It is not
obvious that this condition affects performance in practice, so I am
removing it instead of trying to come up with a more complex mechanism
to preserve the condition.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20230530180959.1108766-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-06-01 07:34:03 -04:00
Stefan Hajnoczi
6a6da231b7 block/io_uring: convert to blk_io_plug_call() API
Stop using the .bdrv_co_io_plug() API because it is not multi-queue
block layer friendly. Use the new blk_io_plug_call() API to batch I/O
submission instead.

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: 20230530180959.1108766-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-06-01 07:34:03 -04:00
Stefan Hajnoczi
60f782b6b7 aio: remove aio_disable_external() API
All callers now pass is_external=false to aio_set_fd_handler() and
aio_set_event_notifier(). The aio_disable_external() API that
temporarily disables fd handlers that were registered is_external=true
is therefore dead code.

Remove aio_disable_external(), aio_enable_external(), and the
is_external arguments to aio_set_fd_handler() and
aio_set_event_notifier().

The entire test-fdmon-epoll test is removed because its sole purpose was
testing aio_disable_external().

Parts of this patch were generated using the following coccinelle
(https://coccinelle.lip6.fr/) semantic patch:

  @@
  expression ctx, fd, is_external, io_read, io_write, io_poll, io_poll_ready, opaque;
  @@
  - aio_set_fd_handler(ctx, fd, is_external, io_read, io_write, io_poll, io_poll_ready, opaque)
  + aio_set_fd_handler(ctx, fd, io_read, io_write, io_poll, io_poll_ready, opaque)

  @@
  expression ctx, notifier, is_external, io_read, io_poll, io_poll_ready;
  @@
  - aio_set_event_notifier(ctx, notifier, is_external, io_read, io_poll, io_poll_ready)
  + aio_set_event_notifier(ctx, notifier, io_read, io_poll, io_poll_ready)

Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230516190238.8401-21-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:37:26 +02:00
Stefan Hajnoczi
3d499a43a2 block/export: don't require AioContext lock around blk_exp_ref/unref()
The FUSE export calls blk_exp_ref/unref() without the AioContext lock.
Instead of fixing the FUSE export, adjust blk_exp_ref/unref() so they
work without the AioContext lock. This way it's less error-prone.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-15-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
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
dea97c1fbd block-coroutine-wrapper: Take AioContext lock in no_co_wrappers
All of the functions that currently take a BlockDriverState, BdrvChild
or BlockBackend as their first parameter expect the associated
AioContext to be locked when they are called. In the case of
no_co_wrappers, they are called from bottom halves directly in the main
loop, so no other caller can be expected to take the lock for them. This
can result in assertion failures because a lock that isn't taken is
released in nested event loops.

Looking at the first parameter is already done by co_wrappers to decide
where the coroutine should run, so doing the same in no_co_wrappers is
only consistent. Take the lock in the generated bottom halves to fix the
problem.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230525124713.401149-2-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:21:23 +02:00
Kevin Wolf
018e5987b5 blockjob: Adhere to rate limit even when reentered early
When jobs are sleeping, for example to enforce a given rate limit, they
can be reentered early, in particular in order to get paused, to update
the rate limit or to get cancelled.

Before this patch, they behave in this case as if they had fully
completed their rate limiting delay. This means that requests are sped
up beyond their limit, violating the constraints that the user gave us.

Change the block jobs to sleep in a loop until the necessary delay is
completed, while still allowing cancelling them immediately as well
pausing (handled by the pause point in job_sleep_ns()) and updating the
rate limit.

This change is also motivated by iotests cases being prone to fail
because drain operations pause and unpause them so often that block jobs
complete earlier than they are supposed to. In particular, the next
commit would fail iotests 030 without this change.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-8-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
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
52eb76f4b1 block: add accounting for zone append operation
Taking account of the new zone append write operation for zoned devices,
BLOCK_ACCT_ZONE_APPEND enum is introduced as other I/O request type (read,
write, flush).

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Message-id: 20230508051916.178322-3-faithilikerun@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-05-15 08:18:10 -04:00
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
Sam Li
72ca800ec5 block/block-common: add zoned device structs
Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.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: 20230508045533.175575-2-faithilikerun@gmail.com
Message-id: 20230324090605.28361-2-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
Kevin Wolf
4f0bef8b36 block: Mark bdrv_query_block_graph_info() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_query_block_graph_info() 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: <20230504115750.54437-19-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
Kevin Wolf
4ee1f854ec graph-lock: Fix GRAPH_RDLOCK_GUARD*() to be reader lock
GRAPH_RDLOCK_GUARD() and GRAPH_RDLOCK_GUARD_MAINLOOP() only take a
reader lock for the graph, so the correct annotation for them to use is
TSA_ASSERT_SHARED rather than TSA_ASSERT.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230504115750.54437-8-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:53 +02:00
Kevin Wolf
d51c349b64 graph-lock: Add GRAPH_UNLOCKED(_PTR)
For some functions, it is part of their interface to be called without
holding the graph lock. Add a new macro to document this.

The macro expands to TSA_EXCLUDES(), which is a relatively weak check
because it passes in cases where the compiler just doesn't know if the
lock is held. Function pointers can't be checked at all. Therefore, its
primary purpose is documentation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-7-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:53 +02:00
Kevin Wolf
b2ab5f545f block: bdrv/blk_co_unref() for calls in coroutine context
These functions must not be called in coroutine context, because they
need write access to the graph.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:53 +02:00
Kevin Wolf
da4afaff07 block: Consistently call bdrv_activate() outside coroutine
Migration code can call bdrv_activate() in coroutine context, whereas
other callers call it outside of coroutines. As it calls other code that
is not supposed to run in coroutines, standardise on running outside of
coroutines.

This adds a no_co_wrapper to switch to the main loop before calling
bdrv_activate().

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-3-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:16:53 +02:00
Stefan Hajnoczi
3edf660a91 aio-wait: avoid AioContext lock in aio_wait_bh_oneshot()
There is no need for the AioContext lock in aio_wait_bh_oneshot().
It's easy to remove the lock from existing callers and then switch from
AIO_WAIT_WHILE() to AIO_WAIT_WHILE_UNLOCKED() in aio_wait_bh_oneshot().

Document that the AioContext lock should not be held across
aio_wait_bh_oneshot(). Holding a lock across aio_poll() can cause
deadlock so we don't want callers to do that.

This is a step towards getting rid of the AioContext lock.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230404153307.458883-1-stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:15:13 +02:00
Paolo Bonzini
17ac39c3e7 block: add missing coroutine_fn annotations
After the recent introduction of many new coroutine callbacks,
a couple calls from non-coroutine_fn to coroutine_fn have sneaked
in; fix them.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20230406101752.242125-1-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10 14:15:13 +02:00
Alexander Bulekov
9c86c97f12 async: Add an optional reentrancy guard to the BH API
Devices can pass their MemoryReentrancyGuard (from their DeviceState),
when creating new BHes. Then, the async API will toggle the guard
before/after calling the BH call-back. This prevents bh->mmio reentrancy
issues.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20230427211013.2994127-3-alxndr@bu.edu>
[thuth: Fix "line over 90 characters" checkpatch.pl error]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2023-04-28 11:31:07 +02:00
Emanuele Giuseppe Esposito
aef04fc790 thread-pool: avoid passing the pool parameter every time
thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool runs only in the same thread that is submitting
work to it, it can't run anywhere else.

Therefore simplify the thread_pool_submit* API and remove the
ThreadPool function parameter.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-5-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-25 13:17:28 +02:00
Emanuele Giuseppe Esposito
0fdb73112b thread-pool: use ThreadPool from the running thread
Use qemu_get_current_aio_context() where possible, since we always
submit work to the current thread anyways.

We want to also be sure that the thread submitting the work is
the same as the one processing the pool, to avoid adding
synchronization to the pool list.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-4-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-25 13:17:28 +02:00
Emanuele Giuseppe Esposito
a75e4e4365 io_uring: use LuringState from the running thread
Remove usage of aio_context_acquire by always submitting asynchronous
AIO to the current thread's LuringState.

In order to prevent mistakes from the caller side, avoid passing LuringState
in luring_io_{plug/unplug} and luring_co_submit, and document the functions
to make clear that they work in the current thread's AioContext.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-3-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-25 13:17:28 +02:00
Emanuele Giuseppe Esposito
ab50533b69 linux-aio: use LinuxAioState from the running thread
Remove usage of aio_context_acquire by always submitting asynchronous
AIO to the current thread's LinuxAioState.

In order to prevent mistakes from the caller side, avoid passing LinuxAioState
in laio_io_{plug/unplug} and laio_co_submit, and document the functions
to make clear that they work in the current thread's AioContext.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-2-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-25 13:17:28 +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
81f730d4d0 block, block-backend: write some hot coroutine wrappers by hand
The introduction of the graph lock is causing blk_get_geometry, a hot function
used in the I/O path, to create a coroutine.  However, the only part that really
needs to run in coroutine context is the call to bdrv_co_refresh_total_sectors,
which in turn only happens in the rare case of host CD-ROM devices.

So, write by hand the three wrappers on the path from blk_co_get_geometry to
bdrv_co_refresh_total_sectors, so that the coroutine wrapper is only created
if bdrv_nb_sectors actually calls bdrv_refresh_total_sectors.

Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20230407153303.391121-9-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-11 16:46:49 +02:00
Paolo Bonzini
e5203a3b5d block-backend: inline bdrv_co_get_geometry
bdrv_co_get_geometry is only used in blk_co_get_geometry.  Inline it in
there, to reduce the number of wrappers for bs->total_sectors.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20230407153303.391121-7-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 16:40:54 +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
d8fbf9aa85 block/export: Fix graph locking in blk_get_geometry() call
blk_get_geometry() eventually calls bdrv_nb_sectors(), which is a
co_wrapper_mixed_bdrv_rdlock. This means that when it is called from
coroutine context, it already assume to have the graph locked.

However, virtio_blk_sect_range_ok() in block/export/virtio-blk-handler.c
(used by vhost-user-blk and VDUSE exports) runs in a coroutine, but
doesn't take the graph lock - blk_*() functions are generally expected
to do that internally. This causes an assertion failure when accessing
an export for the first time if it runs in an iothread.

This is an example of the crash:

  $ ./storage-daemon/qemu-storage-daemon --object iothread,id=th0 --blockdev file,filename=/home/kwolf/images/hd.img,node-name=disk --export vhost-user-blk,addr.type=unix,addr.path=/tmp/vhost.sock,node-name=disk,id=exp0,iothread=th0
  qemu-storage-daemon: ../block/graph-lock.c:268: void assert_bdrv_graph_readable(void): Assertion `qemu_in_main_thread() || reader_count()' failed.

  (gdb) bt
  #0  0x00007ffff6eafe5c in __pthread_kill_implementation () from /lib64/libc.so.6
  #1  0x00007ffff6e5fa76 in raise () from /lib64/libc.so.6
  #2  0x00007ffff6e497fc in abort () from /lib64/libc.so.6
  #3  0x00007ffff6e4971b in __assert_fail_base.cold () from /lib64/libc.so.6
  #4  0x00007ffff6e58656 in __assert_fail () from /lib64/libc.so.6
  #5  0x00005555556337a3 in assert_bdrv_graph_readable () at ../block/graph-lock.c:268
  #6  0x00005555555fd5a2 in bdrv_co_nb_sectors (bs=0x5555564c5ef0) at ../block.c:5847
  #7  0x00005555555ee949 in bdrv_nb_sectors (bs=0x5555564c5ef0) at block/block-gen.c:256
  #8  0x00005555555fd6b9 in bdrv_get_geometry (bs=0x5555564c5ef0, nb_sectors_ptr=0x7fffef7fedd0) at ../block.c:5884
  #9  0x000055555562ad6d in blk_get_geometry (blk=0x5555564cb200, nb_sectors_ptr=0x7fffef7fedd0) at ../block/block-backend.c:1624
  #10 0x00005555555ddb74 in virtio_blk_sect_range_ok (blk=0x5555564cb200, block_size=512, sector=0, size=512) at ../block/export/virtio-blk-handler.c:44
  #11 0x00005555555dd80d in virtio_blk_process_req (handler=0x5555564cbb98, in_iov=0x7fffe8003830, out_iov=0x7fffe8003860, in_num=1, out_num=0) at ../block/export/virtio-blk-handler.c:189
  #12 0x00005555555dd546 in vu_blk_virtio_process_req (opaque=0x7fffe8003800) at ../block/export/vhost-user-blk-server.c:66
  #13 0x00005555557bf4a1 in coroutine_trampoline (i0=-402635264, i1=32767) at ../util/coroutine-ucontext.c:177
  #14 0x00007ffff6e75c20 in ?? () from /lib64/libc.so.6
  #15 0x00007fffefffa870 in ?? ()
  #16 0x0000000000000000 in ?? ()

Fix this by creating a new blk_co_get_geometry() that takes the lock,
and changing blk_get_geometry() to be a co_wrapper_mixed around it.

To make the resulting code cleaner, virtio-blk-handler.c can directly
call the coroutine version now (though that wouldn't be necessary for
fixing the bug, taking the lock in blk_co_get_geometry() is what fixes
it).

Fixes: 8ab8140a04
Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230327113959.60071-1-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-03-27 15:16:05 +02:00
Marc-André Lureau
6eeef4477a aio: make aio_set_fd_poll() static to aio-posix.c
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-9-marcandre.lureau@redhat.com>
2023-03-13 15:23:37 +04:00
Peter Maydell
7b0f0aa55f * Fix missing memory barriers
* Fix comments about memory ordering
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Merge tag 'for-upstream-mb' of https://gitlab.com/bonzini/qemu into staging

* Fix missing memory barriers
* Fix comments about memory ordering

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* tag 'for-upstream-mb' of https://gitlab.com/bonzini/qemu:
  async: clarify usage of barriers in the polling case
  async: update documentation of the memory barriers
  physmem: add missing memory barrier
  qemu-coroutine-lock: add smp_mb__after_rmw()
  aio-wait: switch to smp_mb__after_rmw()
  edu: add smp_mb__after_rmw()
  qemu-thread-win32: cleanup, fix, document QemuEvent
  qemu-thread-posix: cleanup, fix, document QemuEvent
  qatomic: add smp_mb__before/after_rmw()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-03-07 17:02:06 +00:00
Paolo Bonzini
b532526a07 aio-wait: switch to smp_mb__after_rmw()
The barrier comes after an atomic increment, so it is enough to use
smp_mb__after_rmw(); this avoids a double barrier on x86 systems.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-03-07 12:39:50 +01:00
Jesper Devantier
73064edfb8 hw/nvme: flexible data placement emulation
Add emulation of TP4146 ("Flexible Data Placement").

Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jesper Devantier <j.devantier@samsung.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2023-03-06 15:28:02 +01:00
Gollu Appalanaidu
e181d3da39 hw/nvme: basic directives support
Add support for the Directive Send and Recv commands and the Identify
directive.

Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Gollu Appalanaidu <anaidu.gollu@samsung.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2023-03-06 15:28:02 +01:00
Klaus Jensen
771dbc3ac4 hw/nvme: add basic endurance group support
Add the mandatory Endurance Group identify data structures and log
pages.

For now, all namespaces in a subsystem belongs to a single Endurance
Group.

Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2023-03-06 15:28:02 +01:00
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