Commit Graph
93 Commits
Author SHA1 Message Date
Stefan HajnocziandKevin Wolf 23c983c8f6 block: remove outdated AioContext locking comments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
Stefan HajnocziandKevin Wolf b49f4755c7 block: remove AioContext locking
This is the big patch that removes
aio_context_acquire()/aio_context_release() from the block layer and
affected block layer users.

There isn't a clean way to split this patch and the reviewers are likely
the same group of people, so I decided to do it in one patch.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-ID: <20231205182011.1976568-7-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-12-21 22:49:27 +01:00
Kevin Wolf 411132c979 export/vhost-user-blk: Fix consecutive drains
The vhost-user-blk export implement AioContext switches in its drain
implementation. This means that on drain_begin, it detaches the server
from its AioContext and on drain_end, attaches it again and schedules
the server->co_trip coroutine in the updated AioContext.

However, nothing guarantees that server->co_trip is even safe to be
scheduled. Not only is it unclear that the coroutine is actually in a
state where it can be reentered externally without causing problems, but
with two consecutive drains, it is possible that the scheduled coroutine
didn't have a chance yet to run and trying to schedule an already
scheduled coroutine a second time crashes with an assertion failure.

Following the model of NBD, this commit makes the vhost-user-blk export
shut down server->co_trip during drain so that resuming the export means
creating and scheduling a new coroutine, which is always safe.

There is one exception: If the drain call didn't poll (for example, this
happens in the context of bdrv_graph_wrlock()), then the coroutine
didn't have a chance to shut down. However, in this case the AioContext
can't have changed; changing the AioContext always involves a polling
drain. So in this case we can simply assert that the AioContext is
unchanged and just leave the coroutine running or wake it up if it has
yielded to wait for the AioContext to be attached again.

Fixes: e1054cd4aa
Fixes: https://issues.redhat.com/browse/RHEL-1708
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231127115755.22846-1-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-11-28 14:56:32 +01:00
Kevin Wolf 2b3912f135 block: Mark bdrv_first_blk() and bdrv_is_root_node() GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_first_blk() and bdrv_is_root_node() need to hold a reader lock
for the graph. These functions are the only functions in block-backend.c
that access the parent list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-5-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
Michael Tokarev 3202d8e404 block: spelling fixes
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
2023-09-08 13:08:52 +03:00
Manos PitsidianakisandMichael S. Tsirkin f8ed3648b5 vhost-user: fully use new backend/frontend naming
Slave/master nomenclature was replaced with backend/frontend in commit
1fc19b6527 ("vhost-user: Adopt new backend naming")

This patch replaces all remaining uses of master and slave in the
codebase.

Signed-off-by: Emmanouil Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <20230613080849.2115347-1-manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2023-06-26 09:50:00 -04:00
Stefan HajnocziandKevin Wolf 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 HajnocziandKevin Wolf 17b69c0fc1 block/fuse: do not set is_external=true on FUSE fd
This is part of ongoing work to remove the aio_disable_external() API.

Use BlockDevOps .drained_begin/end/poll() instead of
aio_set_fd_handler(is_external=true).

As a side-effect the FUSE export now follows AioContext changes like the
other export types.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-16-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
Stefan HajnocziandKevin Wolf 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 HajnocziandKevin Wolf 195332c1d9 block/export: rewrite vduse-blk drain code
vduse_blk_detach_ctx() waits for in-flight requests using
AIO_WAIT_WHILE(). This is not allowed according to a comment in
bdrv_set_aio_context_commit():

  /*
   * Take the old AioContex when detaching it from bs.
   * At this point, new_context lock is already acquired, and we are now
   * also taking old_context. This is safe as long as bdrv_detach_aio_context
   * does not call AIO_POLL_WHILE().
   */

Use this opportunity to rewrite the drain code in vduse-blk:

- Use the BlockExport refcount so that vduse_blk_exp_delete() is only
  called when there are no more requests in flight.

- Implement .drained_poll() so in-flight request coroutines are stopped
  by the time .bdrv_detach_aio_context() is called.

- Remove AIO_WAIT_WHILE() from vduse_blk_detach_ctx() to solve the
  .bdrv_detach_aio_context() constraint violation. It's no longer
  needed due to the previous changes.

- Always handle the VDUSE file descriptor, even in drained sections. The
  VDUSE file descriptor doesn't submit I/O, so it's safe to handle it in
  drained sections. This ensures that the VDUSE kernel code gets a fast
  response.

- Suspend virtqueue fd handlers in .drained_begin() and resume them in
  .drained_end(). This eliminates the need for the
  aio_set_fd_handler(is_external=true) flag, which is being removed from
  QEMU.

This is a long list but splitting it into individual commits would
probably lead to git bisect failures - the changes are all related.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-14-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
Stefan HajnocziandKevin Wolf e1054cd4aa block/export: stop using is_external in vhost-user-blk server
vhost-user activity must be suspended during bdrv_drained_begin/end().
This prevents new requests from interfering with whatever is happening
in the drained section.

Previously this was done using aio_set_fd_handler()'s is_external
argument. In a multi-queue block layer world the aio_disable_external()
API cannot be used since multiple AioContext may be processing I/O, not
just one.

Switch to BlockDevOps->drained_begin/end() callbacks.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-8-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
Stefan HajnocziandKevin Wolf 8f5e9a8ee1 block/export: wait for vhost-user-blk requests when draining
Each vhost-user-blk request runs in a coroutine. When the BlockBackend
enters a drained section we need to enter a quiescent state. Currently
any in-flight requests race with bdrv_drained_begin() because it is
unaware of vhost-user-blk requests.

When blk_co_preadv/pwritev()/etc returns it wakes the
bdrv_drained_begin() thread but vhost-user-blk request processing has
not yet finished. The request coroutine continues executing while the
main loop thread thinks it is in a drained section.

One example where this is unsafe is for blk_set_aio_context() where
bdrv_drained_begin() is called before .aio_context_detached() and
.aio_context_attach(). If request coroutines are still running after
bdrv_drained_begin(), then the AioContext could change underneath them
and they race with new requests processed in the new AioContext. This
could lead to virtqueue corruption, for example.

(This example is theoretical, I came across this while reading the
code and have not tried to reproduce it.)

It's easy to make bdrv_drained_begin() wait for in-flight requests: add
a .drained_poll() callback that checks the VuServer's in-flight counter.
VuServer just needs an API that returns true when there are requests in
flight. The in-flight counter needs to be atomic.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-7-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
Stefan HajnocziandKevin Wolf 75d33e8525 util/vhost-user-server: rename refcount to in_flight counter
The VuServer object has a refcount field and ref/unref APIs. The name is
confusing because it's actually an in-flight request counter instead of
a refcount.

Normally a refcount destroys the object upon reaching zero. The VuServer
counter is used to wake up the vhost-user coroutine when there are no
more requests.

Avoid confusing by renaming refcount and ref/unref to in_flight and
inc/dec.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230516190238.8401-6-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-30 17:32:02 +02:00
Kevin Wolf a184563778 block/export: Fix null pointer dereference in error path
There are some error paths in blk_exp_add() that jump to 'fail:' before
'exp' is even created. So we can't just unconditionally access exp->blk.

Add a NULL check, and switch from exp->blk to blk, which is available
earlier, just to be extra sure that we really cover all cases where
BlockDevOps could have been set for it (in practice, this only happens
in drv->create() today, so this part of the change isn't strictly
necessary).

Fixes: Coverity CID 1509238
Fixes: de79b52604
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230510203601.418015-3-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19 19:12:12 +02:00
Stefan HajnocziandEric Blake de79b52604 block/export: call blk_set_dev_ops(blk, NULL, NULL)
Most export types install BlockDeviceOps pointers. It is easy to forget
to remove them because that happens automatically via the "drive" qdev
property in hw/ but not block/export/.

Put blk_set_dev_ops(blk, NULL, NULL) calls in the core export.c code so
the export types don't need to remember.

This fixes the nbd and vhost-user-blk export types.

Fixes: fd6afc501a ("nbd/server: Use drained block ops to quiesce the server")
Fixes: ca858a5fe9 ("vhost-user-blk-server: notify client about disk resize")
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230502211119.720647-1-stefanha@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2023-05-03 14:00:08 -05:00
Richard Henderson 4d1467a568 Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging
Block layer patches

- Protect BlockBackend.queued_requests with its own lock
- Switch to AIO_WAIT_WHILE_UNLOCKED() where possible
- AioContext removal: LinuxAioState/LuringState/ThreadPool
- Add more coroutine_fn annotations, use bdrv/blk_co_*
- Fix crash when execute hmp_commit

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* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (25 commits)
  block/monitor: Fix crash when executing HMP commit
  vmdk: make vmdk_is_cid_valid a coroutine_fn
  qcow2: mark various functions as coroutine_fn and GRAPH_RDLOCK
  tests: mark more coroutine_fns
  qemu-pr-helper: mark more coroutine_fns
  9pfs: mark more coroutine_fns
  nbd: mark more coroutine_fns, do not use co_wrappers
  mirror: make mirror_flush a coroutine_fn, do not use co_wrappers
  blkdebug: add missing coroutine_fn annotation
  vvfat: mark various functions as coroutine_fn
  thread-pool: avoid passing the pool parameter every time
  thread-pool: use ThreadPool from the running thread
  io_uring: use LuringState from the running thread
  linux-aio: use LinuxAioState from the running thread
  block: add missing coroutine_fn to bdrv_sum_allocated_file_size()
  include/block: fixup typos
  monitor: convert monitor_cleanup() to AIO_WAIT_WHILE_UNLOCKED()
  hmp: convert handle_hmp_command() to AIO_WAIT_WHILE_UNLOCKED()
  block: convert bdrv_drain_all_begin() to AIO_WAIT_WHILE_UNLOCKED()
  block: convert bdrv_graph_wrlock() to AIO_WAIT_WHILE_UNLOCKED()
  ...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-04-26 07:22:37 +01:00
Stefan HajnocziandKevin Wolf e5568a6603 block: convert blk_exp_close_all_type() to AIO_WAIT_WHILE_UNLOCKED()
There is no change in behavior. Switch to AIO_WAIT_WHILE_UNLOCKED()
instead of AIO_WAIT_WHILE() to document that this code has already been
audited and converted. The AioContext argument is already NULL so
aio_context_release() is never called anyway.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230309190855.414275-3-stefanha@redhat.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-04-25 13:17:28 +02:00
Vladimir Sementsov-OgievskiyandMichael S. Tsirkin ca858a5fe9 vhost-user-blk-server: notify client about disk resize
Currently block_resize qmp command is simply ignored by vhost-user-blk
export. So, the block-node is successfully resized, but virtio config
is unchanged and guest doesn't see that disk is resized.

Let's handle the resize by modifying the config and notifying the guest
appropriately.

After this comment, lsblk in linux guest with attached
vhost-user-blk-pci device shows new size immediately after block_resize
QMP command on vhost-user exported block node.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230321201323.3695923-1-vsementsov@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 04:25:52 -04:00
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
Hanna CzenczekandKevin Wolf 1703eb1c27 block/fuse: Let PUNCH_HOLE write zeroes
fallocate(2) says about PUNCH_HOLE: "After a successful call, subsequent
reads from this range will return zeros."  As it is, PUNCH_HOLE is
implemented as a call to blk_pdiscard(), which does not guarantee this.

We must call blk_pwrite_zeroes() instead.  The difference to ZERO_RANGE
is that we pass the `BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK` flags to
the call -- the storage is supposed to be unmapped, and a slow fallback
by actually writing zeroes as data is not allowed.

Closes: https://gitlab.com/qemu-project/qemu/-/issues/1507
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230227104725.33511-2-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-03-10 15:14:46 +01:00
Markus Armbruster 2ca10faeb8 Fix non-first inclusions of qemu/osdep.h
This commit was created with scripts/clean-includes.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20230202133830.2152150-18-armbru@redhat.com>
2023-02-08 07:28:05 +01:00
Markus Armbruster e2c1c34f13 include/block: Untangle inclusion loops
We have two inclusion loops:

       block/block.h
    -> block/block-global-state.h
    -> block/block-common.h
    -> block/blockjob.h
    -> block/block.h

       block/block.h
    -> block/block-io.h
    -> block/block-common.h
    -> block/blockjob.h
    -> block/block.h

I believe these go back to Emanuele's reorganization of the block API,
merged a few months ago in commit d7e2fe4aac.

Fortunately, breaking them is merely a matter of deleting unnecessary
includes from headers, and adding them back in places where they are
now missing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221221133551.3967339-2-armbru@redhat.com>
2023-01-20 07:24:28 +01:00
Markus Armbruster 54fde4ff06 qapi block: Elide redundant has_FOO in generated C
The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with.  Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step.  This is the step for qapi/block*.json.

Said commit explains the transformation in more detail.

There is one instance of the invariant violation mentioned there:
qcow2_signal_corruption() passes false, "" when node_name is an empty
string.  Take care to pass NULL then.

The previous two commits cleaned up two more.

Additionally, helper bdrv_latency_histogram_stats() loses its output
parameters and returns a value instead.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221104160712.3005652-11-armbru@redhat.com>
[Fixes for #ifndef LIBRBD_SUPPORTS_ENCRYPTION and MacOS squashed in]
2022-12-14 20:03:25 +01:00
Emanuele Giuseppe EspositoandKevin Wolf 142e690712 block: remove bdrv_try_set_aio_context and replace it with bdrv_try_change_aio_context
No functional change intended.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221025084952.2139888-11-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-27 20:14:11 +02:00
Alberto FariaandHanna Reitz a9262f551e block: Change blk_{pread,pwrite}() param order
Swap 'buf' and 'bytes' around for consistency with
blk_co_{pread,pwrite}(), and in preparation to implement these functions
using generated_co_wrapper.

Callers were updated using this Coccinelle script:

    @@ expression blk, offset, buf, bytes, flags; @@
    - blk_pread(blk, offset, buf, bytes, flags)
    + blk_pread(blk, offset, bytes, buf, flags)

    @@ expression blk, offset, buf, bytes, flags; @@
    - blk_pwrite(blk, offset, buf, bytes, flags)
    + blk_pwrite(blk, offset, bytes, buf, flags)

It had no effect on hw/block/nand.c, presumably due to the #if, so that
file was updated manually.

Overly-long lines were then fixed by hand.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-4-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00