Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Graph locking, part 3 (more block drivers)
- Compile out assert_bdrv_graph_readable() by default
- Add c

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Graph locking, part 3 (more block drivers)
- Compile out assert_bdrv_graph_readable() by default
- Add configure options for vmdk, vhdx and vpc
- Fix use after free in blockdev_mark_auto_del()
- migration: Attempt disk reactivation in more failure scenarios
- Coroutine correctness fixes

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# -----END PGP SIGNATURE-----
# gpg: Signature made Wed 10 May 2023 01:18:41 PM BST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (28 commits)
block: compile out assert_bdrv_graph_readable() by default
block: Mark bdrv_refresh_limits() and callers GRAPH_RDLOCK
block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCK
block: Mark bdrv_query_block_graph_info() and callers GRAPH_RDLOCK
block: Mark bdrv_query_bds_stats() and callers GRAPH_RDLOCK
block: Mark BlockDriver callbacks for amend job GRAPH_RDLOCK
block: Mark bdrv_co_debug_event() GRAPH_RDLOCK
block: Mark bdrv_co_get_info() and callers GRAPH_RDLOCK
block: Mark bdrv_co_get_allocated_file_size() and callers GRAPH_RDLOCK
mirror: Require GRAPH_RDLOCK for accessing a node's parent list
vhdx: Require GRAPH_RDLOCK for accessing a node's parent list
nbd: Mark nbd_co_do_establish_connection() and callers GRAPH_RDLOCK
nbd: Remove nbd_co_flush() wrapper function
block: .bdrv_open is non-coroutine and unlocked
graph-lock: Fix GRAPH_RDLOCK_GUARD*() to be reader lock
graph-lock: Add GRAPH_UNLOCKED(_PTR)
test-bdrv-drain: Don't modify the graph in coroutines
iotests: Test resizing image attached to an iothread
block: Don't call no_coroutine_fns in qmp_block_resize()
block: bdrv/blk_co_unref() for calls in coroutine context
...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

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
AI

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>

show more ...

Merge tag 'for-upstream' of git://repo.or.cz/qemu/kevin into staging

Block layer patches

- Add vduse-blk export
- Dirty bitmaps: Fix and improve bitmap merge
- gluster: correctly set max_pdiscard
-

Merge tag 'for-upstream' of git://repo.or.cz/qemu/kevin into staging

Block layer patches

- Add vduse-blk export
- Dirty bitmaps: Fix and improve bitmap merge
- gluster: correctly set max_pdiscard
- rbd: report a better error when namespace does not exist
- aio_wait_kick: add missing memory barrier
- Code cleanups

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# -----END PGP SIGNATURE-----
# gpg: Signature made Fri 24 Jun 2022 08:07:17 AM PDT
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]

* tag 'for-upstream' of git://repo.or.cz/qemu/kevin:
vduse-blk: Add name option
vduse-blk: Add serial option
nbd: Drop dead code spotted by Coverity
aio_wait_kick: add missing memory barrier
block/gluster: correctly set max_pdiscard
block/rbd: report a better error when namespace does not exist
qsd: document vduse-blk exports
libvduse: Add support for reconnecting
vduse-blk: Add vduse-blk resize support
vduse-blk: Implement vduse-blk export
libvduse: Add VDUSE (vDPA Device in Userspace) library
linux-headers: Add vduse.h
block/export: Abstract out the logic of virtio-blk I/O process
block/export: Fix incorrect length passed to vu_queue_push()
block: Support passing NULL ops to blk_set_dev_ops()
block: simplify handling of try to merge different sized bitmaps
block: improve block_dirty_bitmap_merge(): don't allocate extra bitmap
block: block_dirty_bitmap_merge(): fix error path
block: get rid of blk->guest_block_size
block: drop unused bdrv_co_drain() API

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

aio_wait_kick: add missing memory barrier

It seems that aio_wait_kick always required a memory barrier
or atomic operation in the caller, but nobody actually
took care of doing it.

Let's put the ba

aio_wait_kick: add missing memory barrier

It seems that aio_wait_kick always required a memory barrier
or atomic operation in the caller, but nobody actually
took care of doing it.

Let's put the barrier in the function instead, and pair it
with another one in AIO_WAIT_WHILE. Read aio_wait_kick()
comment for further explanation.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220524173054.12651-1-eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

This includes the atomic_ -> qatomic_ rename that touches many files and is
prone to conflicts.

#

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

This includes the atomic_ -> qatomic_ rename that touches many files and is
prone to conflicts.

# gpg: Signature made Wed 23 Sep 2020 17:08:43 BST
# gpg: using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
qemu/atomic.h: rename atomic_ to qatomic_
tests: add test-fdmon-epoll
fdmon-poll: reset npfd when upgrading to fdmon-epoll
gitmodules: add qemu.org vbootrom submodule
gitmodules: switch to qemu.org meson mirror
gitmodules: switch to qemu.org qboot mirror
docs/system: clarify deprecation schedule
virtio-crypto: don't modify elem->in/out_sg
virtio-blk: undo destructive iov_discard_*() operations
util/iov: add iov_discard_undo()
virtio: add vhost-user-fs-ccw device
libvhost-user: handle endianness as mandated by the spec
MAINTAINERS: add Stefan Hajnoczi as block/nvme.c maintainer

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

show more ...

qemu/atomic.h: rename atomic_ to qatomic_

clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when

qemu/atomic.h: rename atomic_ to qatomic_

clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

$ CC=clang CXX=clang++ ./configure ... && make
../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

$ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
sort -u >/tmp/changed_identifiers
$ for identifier in $(</tmp/changed_identifiers); do
sed -i "s%\<$identifier\>%q$identifier%g" \
$(git grep -I -l "\<$identifier\>")
done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/xanclic/tags/pull-block-2018-09-25' into staging

Block layer patches:
- Drain fixes
- node-name parameters for block-commit
- Refactor block jobs to use transac

Merge remote-tracking branch 'remotes/xanclic/tags/pull-block-2018-09-25' into staging

Block layer patches:
- Drain fixes
- node-name parameters for block-commit
- Refactor block jobs to use transactional callbacks for exiting

# gpg: Signature made Tue 25 Sep 2018 16:12:44 BST
# gpg: using RSA key F407DB0061D5CF40
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>"
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1 1829 F407 DB00 61D5 CF40

* remotes/xanclic/tags/pull-block-2018-09-25: (42 commits)
test-bdrv-drain: Test draining job source child and parent
block: Use a single global AioWait
test-bdrv-drain: Fix outdated comments
test-bdrv-drain: AIO_WAIT_WHILE() in job .commit/.abort
job: Avoid deadlocks in job_completed_txn_abort()
test-bdrv-drain: Test nested poll in bdrv_drain_poll_top_level()
block: Remove aio_poll() in bdrv_drain_poll variants
blockjob: Lie better in child_job_drained_poll()
block-backend: Decrease in_flight only after callback
block-backend: Fix potential double blk_delete()
block-backend: Add .drained_poll callback
block: Add missing locking in bdrv_co_drain_bh_cb()
test-bdrv-drain: Test AIO_WAIT_WHILE() in completion callback
job: Use AIO_WAIT_WHILE() in job_finish_sync()
test-blockjob: Acquire AioContext around job_cancel_sync()
test-bdrv-drain: Drain with block jobs in an I/O thread
aio-wait: Increase num_waiters even in home thread
blockjob: Wake up BDS when job becomes idle
job: Fix missing locking due to mismerge
job: Fix nested aio_poll() hanging in job_txn_apply
...

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

show more ...

Merge remote-tracking branch 'kevin/tags/for-upstream' into block

Block layer patches:

- Fix some jobs/drain/aio_poll related hangs
- commit: Add top-node/base-node options
- linux-aio: Fix locking

Merge remote-tracking branch 'kevin/tags/for-upstream' into block

Block layer patches:

- Fix some jobs/drain/aio_poll related hangs
- commit: Add top-node/base-node options
- linux-aio: Fix locking for qemu_laio_process_completions()
- Fix use after free error in bdrv_open_inherit

# gpg: Signature made Tue Sep 25 15:54:01 2018 CEST
# gpg: using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6

* kevin/tags/for-upstream: (26 commits)
test-bdrv-drain: Test draining job source child and parent
block: Use a single global AioWait
test-bdrv-drain: Fix outdated comments
test-bdrv-drain: AIO_WAIT_WHILE() in job .commit/.abort
job: Avoid deadlocks in job_completed_txn_abort()
test-bdrv-drain: Test nested poll in bdrv_drain_poll_top_level()
block: Remove aio_poll() in bdrv_drain_poll variants
blockjob: Lie better in child_job_drained_poll()
block-backend: Decrease in_flight only after callback
block-backend: Fix potential double blk_delete()
block-backend: Add .drained_poll callback
block: Add missing locking in bdrv_co_drain_bh_cb()
test-bdrv-drain: Test AIO_WAIT_WHILE() in completion callback
job: Use AIO_WAIT_WHILE() in job_finish_sync()
test-blockjob: Acquire AioContext around job_cancel_sync()
test-bdrv-drain: Drain with block jobs in an I/O thread
aio-wait: Increase num_waiters even in home thread
blockjob: Wake up BDS when job becomes idle
job: Fix missing locking due to mismerge
job: Fix nested aio_poll() hanging in job_txn_apply
...

Signed-off-by: Max Reitz <mreitz@redhat.com>

show more ...

block: Use a single global AioWait

When draining a block node, we recurse to its parent and for subtree
drains also to its children. A single AIO_WAIT_WHILE() is then used to
wait for bdrv_drain_pol

block: Use a single global AioWait

When draining a block node, we recurse to its parent and for subtree
drains also to its children. A single AIO_WAIT_WHILE() is then used to
wait for bdrv_drain_poll() to become true, which depends on all of the
nodes we recursed to. However, if the respective child or parent becomes
quiescent and calls bdrv_wakeup(), only the AioWait of the child/parent
is checked, while AIO_WAIT_WHILE() depends on the AioWait of the
original node.

Fix this by using a single AioWait for all callers of AIO_WAIT_WHILE().

This may mean that the draining thread gets a few more unnecessary
wakeups because an unrelated operation got completed, but we already
wake it up when something _could_ have changed rather than only if it
has certainly changed.

Apart from that, drain is a slow path anyway. In theory it would be
possible to use wakeups more selectively and still correctly, but the
gains are likely not worth the additional complexity. In fact, this
patch is a nice simplification for some places in the code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Mon 12 Mar 2018 16:01:16 GMT
# gpg: using RSA key 9CA4ABB381AB73C8
# gpg: Go

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Mon 12 Mar 2018 16:01:16 GMT
# gpg: using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
block: make BDRV_POLL_WHILE() re-entrancy safe

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

show more ...

block: make BDRV_POLL_WHILE() re-entrancy safe

Nested BDRV_POLL_WHILE() calls can occur. Currently
assert(!wait_->wakeup) fails in AIO_WAIT_WHILE() when this happens.

This patch converts the bool

block: make BDRV_POLL_WHILE() re-entrancy safe

Nested BDRV_POLL_WHILE() calls can occur. Currently
assert(!wait_->wakeup) fails in AIO_WAIT_WHILE() when this happens.

This patch converts the bool wait_->need_kick flag to an unsigned
wait_->num_waiters counter.

Nesting works correctly because outer AIO_WAIT_WHILE() callers evaluate
the condition again after the inner caller completes (invoking the inner
caller counts as aio_poll() progress).

Reported-by: "fuweiwei (C)" <fuweiwei2@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20180307124619.6218-1-stefanha@redhat.com
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Fri 09 Mar 2018 13:19:02 GMT
# gpg: using RSA key 9CA4ABB381AB73C8
# gpg: Go

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Fri 09 Mar 2018 13:19:02 GMT
# gpg: using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
vl: introduce vm_shutdown()
virtio-scsi: fix race between .ioeventfd_stop() and vq handler
virtio-blk: fix race between .ioeventfd_stop() and vq handler
block: add aio_wait_bh_oneshot()
virtio-blk: dataplane: Don't batch notifications if EVENT_IDX is present
README: Fix typo 'git-publish'
block: Fix qemu crash when using scsi-block

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

show more ...

block: add aio_wait_bh_oneshot()

Sometimes it's necessary for the main loop thread to run a BH in an
IOThread and wait for its completion. This primitive is useful during
startup/shutdown to synchr

block: add aio_wait_bh_oneshot()

Sometimes it's necessary for the main loop thread to run a BH in an
IOThread and wait for its completion. This primitive is useful during
startup/shutdown to synchronize and avoid race conditions.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20180307144205.20619-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Mon 05 Mar 2018 17:45:51 GMT
# gpg: using RSA key 7F09B272C88F2F

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Mon 05 Mar 2018 17:45:51 GMT
# gpg: using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (38 commits)
block: Fix NULL dereference on empty drive error
qcow2: Replace align_offset() with ROUND_UP()
block/ssh: Add basic .bdrv_truncate()
block/ssh: Make ssh_grow_file() blocking
block/ssh: Pull ssh_grow_file() from ssh_create()
qemu-img: Make resize error message more general
qcow2: make qcow2_co_create2() a coroutine_fn
block: rename .bdrv_create() to .bdrv_co_create_opts()
Revert "IDE: Do not flush empty CDROM drives"
block: test blk_aio_flush() with blk->root == NULL
block: add BlockBackend->in_flight counter
block: extract AIO_WAIT_WHILE() from BlockDriverState
aio: rename aio_context_in_iothread() to in_aio_context_home_thread()
docs: document how to use the l2-cache-entry-size parameter
specs/qcow2: Fix documentation of the compressed cluster descriptor
iotest 033: add misaligned write-zeroes test via truncate
block: fix write with zero flag set and iovector provided
block: Drop unused .bdrv_co_get_block_status()
vvfat: Switch to .bdrv_co_block_status()
vpc: Switch to .bdrv_co_block_status()
...

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

# Conflicts:
# include/block/block.h

show more ...

block: extract AIO_WAIT_WHILE() from BlockDriverState

BlockDriverState has the BDRV_POLL_WHILE() macro to wait on event loop
activity while a condition evaluates to true. This is used to implement

block: extract AIO_WAIT_WHILE() from BlockDriverState

BlockDriverState has the BDRV_POLL_WHILE() macro to wait on event loop
activity while a condition evaluates to true. This is used to implement
synchronous operations where it acts as a condvar between the IOThread
running the operation and the main loop waiting for the operation. It
can also be called from the thread that owns the AioContext and in that
case it's just a nested event loop.

BlockBackend needs this behavior but doesn't always have a
BlockDriverState it can use. This patch extracts BDRV_POLL_WHILE() into
the AioWait abstraction, which can be used with AioContext and isn't
tied to BlockDriverState anymore.

This feature could be built directly into AioContext but then all users
would kick the event loop even if they signal different conditions.
Imagine an AioContext with many BlockDriverStates, each time a request
completes any waiter would wake up and re-check their condition. It's
nicer to keep a separate AioWait object for each condition instead.

Please see "block/aio-wait.h" for details on the API.

The name AIO_WAIT_WHILE() avoids the confusion between AIO_POLL_WHILE()
and AioContext polling.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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