block: Mark bdrv_apply_auto_read_only() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_apply_auto_read_only() need to hold a reader lock for the graph
be

block: Mark bdrv_apply_auto_read_only() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_apply_auto_read_only() need to hold a reader lock for the graph
because it calls bdrv_can_set_read_only(), which indirectly accesses the
parents list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-19-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block: Mark bdrv_apply_auto_read_only() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_apply_auto_read_only() need to hold a reader lock for the graph
be

block: Mark bdrv_apply_auto_read_only() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_apply_auto_read_only() need to hold a reader lock for the graph
because it calls bdrv_can_set_read_only(), which indirectly accesses the
parents list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-19-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

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 handle

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>

show more ...

block: Handle curl 7.55.0, 7.85.0 version changes

* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates

block: Handle curl 7.55.0, 7.85.0 version changes

* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates CURLOPT_PROTOCOLS and CURLOPT_REDIR_PROTOCOLS in
favour of *_STR variants, specifying the desired protocols via a
string.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1440
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230123201431.23118-1-anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: Fix error path in curl_open()

g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failur

curl: Fix error path in curl_open()

g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failures (just print, no abort).

There are several paths in curl_open() that can lead to the out_noclean
label without s->sockets being allocated, so clean it only if it has
been allocated.

Example reproducer:
$ qemu-img info -f http ''
qemu-img: GLib: g_hash_table_foreach_remove: assertion 'hash_table != NULL' failed
qemu-img: GLib: g_hash_table_destroy: assertion 'hash_table != NULL' failed
qemu-img: Could not open '': http curl driver cannot handle the URL '' (does not start with 'http://')

Closes: https://gitlab.com/qemu-project/qemu/-/issues/1475
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230206132949.92917-1-hreitz@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block: Handle curl 7.55.0, 7.85.0 version changes

* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates

block: Handle curl 7.55.0, 7.85.0 version changes

* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates CURLOPT_PROTOCOLS and CURLOPT_REDIR_PROTOCOLS in
favour of *_STR variants, specifying the desired protocols via a
string.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1440
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230123201431.23118-1-anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: Fix error path in curl_open()

g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failur

curl: Fix error path in curl_open()

g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failures (just print, no abort).

There are several paths in curl_open() that can lead to the out_noclean
label without s->sockets being allocated, so clean it only if it has
been allocated.

Example reproducer:
$ qemu-img info -f http ''
qemu-img: GLib: g_hash_table_foreach_remove: assertion 'hash_table != NULL' failed
qemu-img: GLib: g_hash_table_destroy: assertion 'hash_table != NULL' failed
qemu-img: Could not open '': http curl driver cannot handle the URL '' (does not start with 'http://')

Closes: https://gitlab.com/qemu-project/qemu/-/issues/1475
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230206132949.92917-1-hreitz@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block: Handle curl 7.55.0, 7.85.0 version changes

* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates

block: Handle curl 7.55.0, 7.85.0 version changes

* 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of a *_T
version, which returns curl_off_t instead of a double.
* 7.85.0 deprecates CURLOPT_PROTOCOLS and CURLOPT_REDIR_PROTOCOLS in
favour of *_STR variants, specifying the desired protocols via a
string.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1440
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230123201431.23118-1-anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: Fix error path in curl_open()

g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failur

curl: Fix error path in curl_open()

g_hash_table_destroy() and g_hash_table_foreach_remove() (called by
curl_drop_all_sockets()) both require the table to be non-NULL, or will
print assertion failures (just print, no abort).

There are several paths in curl_open() that can lead to the out_noclean
label without s->sockets being allocated, so clean it only if it has
been allocated.

Example reproducer:
$ qemu-img info -f http ''
qemu-img: GLib: g_hash_table_foreach_remove: assertion 'hash_table != NULL' failed
qemu-img: GLib: g_hash_table_destroy: assertion 'hash_table != NULL' failed
qemu-img: Could not open '': http curl driver cannot handle the URL '' (does not start with 'http://')

Closes: https://gitlab.com/qemu-project/qemu/-/issues/1475
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230206132949.92917-1-hreitz@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed

BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph

block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed

BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph
rdlock since the callback traverses the block nodes graph, which however
is only possible in a coroutine.

Therefore turn it into a co_wrapper to move the actual function into a
coroutine where the lock can be taken.

Because now this function creates a new coroutine and polls, we need to
take the AioContext lock where it is missing, for the only reason that
internally co_wrapper calls AIO_WAIT_WHILE and it expects to release the
AioContext lock.

This is especially messy when a co_wrapper creates a coroutine and polls
in bdrv_open_driver, because this function has so many callers in so
many context that it can easily lead to deadlocks. Therefore the new
rule for bdrv_open_driver is that the caller must always hold the
AioContext lock of the given bs (except if it is a coroutine), because
the function calls bdrv_refresh_total_sectors() which is now a
co_wrapper.

Once the rwlock is ultimated and placed in every place it needs to be,
we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext
lock.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230113204212.359076-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed

BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph

block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed

BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph
rdlock since the callback traverses the block nodes graph, which however
is only possible in a coroutine.

Therefore turn it into a co_wrapper to move the actual function into a
coroutine where the lock can be taken.

Because now this function creates a new coroutine and polls, we need to
take the AioContext lock where it is missing, for the only reason that
internally co_wrapper calls AIO_WAIT_WHILE and it expects to release the
AioContext lock.

This is especially messy when a co_wrapper creates a coroutine and polls
in bdrv_open_driver, because this function has so many callers in so
many context that it can easily lead to deadlocks. Therefore the new
rule for bdrv_open_driver is that the caller must always hold the
AioContext lock of the given bs (except if it is a coroutine), because
the function calls bdrv_refresh_total_sectors() which is now a
co_wrapper.

Once the rwlock is ultimated and placed in every place it needs to be,
we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext
lock.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230113204212.359076-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed

BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph

block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixed

BlockDriver->bdrv_getlength is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph
rdlock since the callback traverses the block nodes graph, which however
is only possible in a coroutine.

Therefore turn it into a co_wrapper to move the actual function into a
coroutine where the lock can be taken.

Because now this function creates a new coroutine and polls, we need to
take the AioContext lock where it is missing, for the only reason that
internally co_wrapper calls AIO_WAIT_WHILE and it expects to release the
AioContext lock.

This is especially messy when a co_wrapper creates a coroutine and polls
in bdrv_open_driver, because this function has so many callers in so
many context that it can easily lead to deadlocks. Therefore the new
rule for bdrv_open_driver is that the caller must always hold the
AioContext lock of the given bs (except if it is a coroutine), because
the function calls bdrv_refresh_total_sectors() which is now a
co_wrapper.

Once the rwlock is ultimated and placed in every place it needs to be,
we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext
lock.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230113204212.359076-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

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

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 d7e2fe4aac8.

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>

show more ...

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

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 d7e2fe4aac8.

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>

show more ...

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this holds.

Reviewed-by: Alberto Faria <afaria@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220922084924.201610-17-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this holds.

Reviewed-by: Alberto Faria <afaria@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220922084924.201610-17-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this holds.

Reviewed-by: Alberto Faria <afaria@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220922084924.201610-17-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this holds.

Reviewed-by: Alberto Faria <afaria@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220922084924.201610-17-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this

curl: add missing coroutine_fn annotations

Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())". Apply coroutine_fn to
functions where this holds.

Reviewed-by: Alberto Faria <afaria@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220922084924.201610-17-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

block/curl.c: Check error return from curl_easy_setopt()

Coverity points out that we aren't checking the return value
from curl_easy_setopt() for any of the calls to it we make
in block/curl.c.

Som

block/curl.c: Check error return from curl_easy_setopt()

Coverity points out that we aren't checking the return value
from curl_easy_setopt() for any of the calls to it we make
in block/curl.c.

Some of these options are documented as always succeeding (e.g.
CURLOPT_VERBOSE) but others have documented failure cases (e.g.
CURLOPT_URL). For consistency we check every call, even the ones
that theoretically cannot fail.

Fixes: Coverity CID 1459336, 1459482, 1460331
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220222152341.850419-3-peter.maydell@linaro.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

show more ...

block/curl.c: Set error message string if curl_init_state() fails

In curl_open(), the 'out' label assumes that the state->errmsg string
has been set (either by curl_easy_perform() or by manually cop

block/curl.c: Set error message string if curl_init_state() fails

In curl_open(), the 'out' label assumes that the state->errmsg string
has been set (either by curl_easy_perform() or by manually copying a
string into it); however if curl_init_state() fails we will jump to
that label without setting the string. Add the missing error string
setup.

(We can't be specific about the cause of failure: the documentation
of curl_easy_init() just says "If this function returns NULL,
something went wrong".)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220222152341.850419-2-peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

show more ...

aio-posix: split poll check from ready handler

Adaptive polling measures the execution time of the polling check plus
handlers called when a polled event becomes ready. Handlers can take a
significa

aio-posix: split poll check from ready handler

Adaptive polling measures the execution time of the polling check plus
handlers called when a polled event becomes ready. Handlers can take a
significant amount of time, making it look like polling was running for
a long time when in fact the event handler was running for a long time.

For example, on Linux the io_submit(2) syscall invoked when a virtio-blk
device's virtqueue becomes ready can take 10s of microseconds. This
can exceed the default polling interval (32 microseconds) and cause
adaptive polling to stop polling.

By excluding the handler's execution time from the polling check we make
the adaptive polling calculation more accurate. As a result, the event
loop now stays in polling mode where previously it would have fallen
back to file descriptor monitoring.

The following data was collected with virtio-blk num-queues=2
event_idx=off using an IOThread. Before:

168k IOPS, IOThread syscalls:

9837.115 ( 0.020 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 16, iocbpp: 0x7fcb9f937db0) = 16
9837.158 ( 0.002 ms): IO iothread1/620155 write(fd: 103, buf: 0x556a2ef71b88, count: 8) = 8
9837.161 ( 0.001 ms): IO iothread1/620155 write(fd: 104, buf: 0x556a2ef71b88, count: 8) = 8
9837.163 ( 0.001 ms): IO iothread1/620155 ppoll(ufds: 0x7fcb90002800, nfds: 4, tsp: 0x7fcb9f1342d0, sigsetsize: 8) = 3
9837.164 ( 0.001 ms): IO iothread1/620155 read(fd: 107, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.174 ( 0.001 ms): IO iothread1/620155 read(fd: 105, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.176 ( 0.001 ms): IO iothread1/620155 read(fd: 106, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.209 ( 0.035 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 32, iocbpp: 0x7fca7d0cebe0) = 32

174k IOPS (+3.6%), IOThread syscalls:

9809.566 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0cdd62be0) = 32
9809.625 ( 0.001 ms): IO iothread1/623061 write(fd: 103, buf: 0x5647cfba5f58, count: 8) = 8
9809.627 ( 0.002 ms): IO iothread1/623061 write(fd: 104, buf: 0x5647cfba5f58, count: 8) = 8
9809.663 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0d0388b50) = 32

Notice that ppoll(2) and eventfd read(2) syscalls are eliminated because
the IOThread stays in polling mode instead of falling back to file
descriptor monitoring.

As usual, polling is not implemented on Windows so this patch ignores
the new io_poll_read() callback in aio-win32.c.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-2-stefanha@redhat.com

[Fixed up aio_set_event_notifier() calls in
tests/unit/test-fdmon-epoll.c added after this series was queued.
--Stefan]

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

block: use int64_t instead of uint64_t in driver read handlers

We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit writ

block: use int64_t instead of uint64_t in driver read handlers

We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert driver read handlers parameters which are already 64bit to
signed type.

While being here, convert also flags parameter to be BdrvRequestFlags.

Now let's consider all callers. Simple

git grep '\->bdrv_\(aio\|co\)_preadv\(_part\)\?'

shows that's there three callers of driver function:

bdrv_driver_preadv() in block/io.c, passes int64_t, checked by
bdrv_check_qiov_request() to be non-negative.

qcow2_load_vmstate() does bdrv_check_qiov_request().

do_perform_cow_read() has uint64_t argument. And a lot of things in
qcow2 driver are uint64_t, so converting it is big job. But we must
not work with requests that don't satisfy bdrv_check_qiov_request(),
so let's just assert it here.

Still, the functions may be called directly, not only by drv->...
Let's check:

git grep '\.bdrv_\(aio\|co\)_preadv\(_part\)\?\s*=' | \
awk '{print $4}' | sed 's/,//' | sed 's/&//' | sort | uniq | \
while read func; do git grep "$func(" | \
grep -v "$func(BlockDriverState"; done

The only one such caller:

QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1);
...
ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0);

in tests/unit/test-bdrv-drain.c, and it's OK obviously.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-4-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: fix typos]
Signed-off-by: Eric Blake <eblake@redhat.com>

show more ...

curl: Disconnect sockets from CURLState

When a curl transfer is finished, that does not mean that CURL lets go
of all the sockets it used for it. We therefore must not free a
CURLSocket object befo

curl: Disconnect sockets from CURLState

When a curl transfer is finished, that does not mean that CURL lets go
of all the sockets it used for it. We therefore must not free a
CURLSocket object before CURL has invoked curl_sock_cb() to tell us to
remove it. Otherwise, we may get a use-after-free, as described in this
bug report: https://bugs.launchpad.net/qemu/+bug/1916501

(Reproducer from that report:
$ qemu-img convert -f qcow2 -O raw \
https://download.cirros-cloud.net/0.4.0/cirros-0.4.0-x86_64-disk.img \
out.img
)

(Alternatively, it might seem logical to force-drop all sockets that
have been used for a state when the respective transfer is done, kind of
like it is done now, but including unsetting the AIO handlers.
Unfortunately, doing so makes the driver just hang instead of crashing,
which seems to evidence that CURL still uses those sockets.)

Make the CURLSocket object independent of "its" CURLState by putting all
sockets into a hash table belonging to the BDRVCURLState instead of a
list that belongs to a CURLState. Do not touch any sockets in
curl_clean_state().

Testing, it seems like all sockets are indeed gone by the time the curl
BDS is closed, so it seems like there really was no point in freeing any
socket just because a transfer is done. libcurl does invoke
curl_sock_cb() with CURL_POLL_REMOVE for every socket it has.

Buglink: https://bugs.launchpad.net/qemu/+bug/1916501
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210309130541.37540-3-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

curl: Store BDRVCURLState pointer in CURLSocket

A socket does not really belong to any specific state. We do not need
to store a pointer to "its" state in it, a pointer to the common
BDRVCURLState

curl: Store BDRVCURLState pointer in CURLSocket

A socket does not really belong to any specific state. We do not need
to store a pointer to "its" state in it, a pointer to the common
BDRVCURLState is sufficient.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210309130541.37540-2-mreitz@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...