Commit Graph

32 Commits

Author SHA1 Message Date
Kevin Wolf
b59b466071 block: Protect bs->parents with graph_lock
Almost all functions that access the parent link already take the graph
lock now. Add locking to the remaining user in a test case and finally
annotate the struct field itself as protected by the graph lock.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-21-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-10-12 16:31:33 +02:00
Kevin Wolf
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
Kevin Wolf
487b91870f block: Take AioContext lock for bdrv_append() more consistently
The documentation for bdrv_append() says that the caller must hold the
AioContext lock for bs_top. Change all callers to actually adhere to the
contract.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230911094620.45040-5-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-09-20 17:46:00 +02:00
Kevin Wolf
2065cf6b23 test-block-iothread: Lock AioContext for blk_insert_bs()
blk_insert_bs() requires that callers hold the AioContext lock for the
node that should be inserted. Take it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230605085711.21261-4-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-06-28 08:46:08 +02:00
Kevin Wolf
6e01215932 raw-format: Fix open with 'file' in iothread
When opening the 'file' child moves bs to an iothread, we need to hold
the AioContext lock of it before we can call raw_apply_options() (and
more specifically, bdrv_getlength() inside of it).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230525124713.401149-8-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
c6e0a6de62 block: Take main AioContext lock when calling bdrv_open()
The function documentation already says that all callers must hold the
main AioContext lock, but not all of them do. This can cause assertion
failures when functions called by bdrv_open() try to drop the lock. Fix
a few more callers to take the lock before calling bdrv_open().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230525124713.401149-4-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
7ff9579e60 block: Mark bdrv_co_block_status() and callers GRAPH_RDLOCK
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_block_status() need to hold a reader lock for the graph.

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

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-5-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23 19:49:07 +01:00
Emanuele Giuseppe Esposito
c86422c554 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>
2023-02-01 16:52:32 +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
Emanuele Giuseppe Esposito
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
Emanuele Giuseppe Esposito
6f592e5aca job.c: enable job lock/unlock and remove Aiocontext locks
Change the job_{lock/unlock} and macros to use job_mutex.

Now that they are not nop anymore, remove the aiocontext
to avoid deadlocks.

Therefore:
- when possible, remove completely the aiocontext lock/unlock pair
- if it is used by some other function too, reduce the locking
  section as much as possible, leaving the job API outside.
- change AIO_WAIT_WHILE in AIO_WAIT_WHILE_UNLOCKED, since we
  are not using the aiocontext lock anymore

The only functions that still need the aiocontext lock are:
- the JobDriver callbacks, already documented in job.h
- job_cancel_sync() in replication.c is called with aio_context_lock
  taken, but now job is using AIO_WAIT_WHILE_UNLOCKED so we need to
  release the lock.

Reduce the locking section to only cover the callback invocation
and document the functions that take the AioContext lock,
to avoid taking it twice.

Also remove real_job_{lock/unlock}, as they are replaced by the
public functions.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220926093214.506243-19-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-07 12:11:41 +02:00
Emanuele Giuseppe Esposito
191e7af394 jobs: use job locks also in the unit tests
Add missing job synchronization in the unit tests, with
explicit locks.

We are deliberately using _locked functions wrapped by a guard
instead of a normal call because the normal call will be removed
in future, as the only usage is limited to the tests.

In other words, if a function like job_pause() is/will be only used
in tests to avoid:

WITH_JOB_LOCK_GUARD(){
    job_pause_locked();
}

then it is not worth keeping job_pause(), and just use the guard.

Note: at this stage, job_{lock/unlock} and job lock guard macros
are *nop*.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20220926093214.506243-10-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-07 12:11:41 +02:00
Alberto Faria
015ed2529a block: Add blk_co_truncate()
Also convert blk_truncate() into a generated_co_wrapper.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-17-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
1c95dc914a block: Implement blk_pwrite_zeroes() using generated_co_wrapper
Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-13-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
2c9715fa28 block: Add blk_co_pwrite_compressed()
Also convert blk_pwrite_compressed() into a generated_co_wrapper.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-12-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
09cca043bf block: Export blk_pwritev_part() in block-backend-io.h
Also convert it into a generated_co_wrapper.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-10-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
d1d3fc3d1d block: Add blk_[co_]preadv_part()
Implement blk_preadv_part() using generated_co_wrapper.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-9-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
7c8cd723c7 block: Add blk_{preadv,pwritev}()
Implement them using generated_co_wrapper.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-8-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
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
Alberto Faria
3b35d4542c block: Add a 'flags' param to blk_pread()
For consistency with other I/O functions, and in preparation to
implement it using generated_co_wrapper.

Callers were updated using this Coccinelle script:

    @@ expression blk, offset, buf, bytes; @@
    - blk_pread(blk, offset, buf, bytes)
    + blk_pread(blk, offset, buf, bytes, 0)

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: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220705161527.1054072-3-afaria@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
bf5b16fa40 block: Make blk_{pread,pwrite}() return 0 on success
They currently return the value of their 'bytes' parameter on success.

Make them return 0 instead, for consistency with other I/O functions and
in preparation to implement them using generated_co_wrapper. This also
makes it clear that short reads/writes are not possible.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Message-Id: <20220705161527.1054072-2-afaria@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:56 +02:00
Alberto Faria
353a5d84b2 block: Make bdrv_{pread,pwrite}() return 0 on success
They currently return the value of their 'bytes' parameter on success.

Make them return 0 instead, for consistency with other I/O functions and
in preparation to implement them using generated_co_wrapper. This also
makes it clear that short reads/writes are not possible.

The few callers that rely on the previous behavior are adjusted
accordingly by hand.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220609152744.3891847-4-afaria@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:55 +02:00
Alberto Faria
32cc71def9 block: Change bdrv_{pread,pwrite,pwrite_sync}() param order
Swap 'buf' and 'bytes' around for consistency with
bdrv_co_{pread,pwrite}(), and in preparation to implement these
functions using generated_co_wrapper.

Callers were updated using this Coccinelle script:

    @@ expression child, offset, buf, bytes, flags; @@
    - bdrv_pread(child, offset, buf, bytes, flags)
    + bdrv_pread(child, offset, bytes, buf, flags)

    @@ expression child, offset, buf, bytes, flags; @@
    - bdrv_pwrite(child, offset, buf, bytes, flags)
    + bdrv_pwrite(child, offset, bytes, buf, flags)

    @@ expression child, offset, buf, bytes, flags; @@
    - bdrv_pwrite_sync(child, offset, buf, bytes, flags)
    + bdrv_pwrite_sync(child, offset, bytes, buf, flags)

Resulting overly-long lines were then fixed by hand.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20220609152744.3891847-3-afaria@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:55 +02:00
Alberto Faria
53fb7844f0 block: Add a 'flags' param to bdrv_{pread,pwrite,pwrite_sync}()
For consistency with other I/O functions, and in preparation to
implement them using generated_co_wrapper.

Callers were updated using this Coccinelle script:

    @@ expression child, offset, buf, bytes; @@
    - bdrv_pread(child, offset, buf, bytes)
    + bdrv_pread(child, offset, buf, bytes, 0)

    @@ expression child, offset, buf, bytes; @@
    - bdrv_pwrite(child, offset, buf, bytes)
    + bdrv_pwrite(child, offset, buf, bytes, 0)

    @@ expression child, offset, buf, bytes; @@
    - bdrv_pwrite_sync(child, offset, buf, bytes)
    + bdrv_pwrite_sync(child, offset, buf, bytes, 0)

Resulting overly-long lines were then fixed by hand.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20220609152744.3891847-2-afaria@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12 12:14:55 +02:00
Emanuele Giuseppe Esposito
3b71719462 block: rename bdrv_invalidate_cache_all, blk_invalidate_cache and test_sync_op_invalidate_cache
Following the bdrv_activate renaming, change also the name
of the respective callers.

bdrv_invalidate_cache_all -> bdrv_activate_all
blk_invalidate_cache -> blk_activate
test_sync_op_invalidate_cache -> test_sync_op_activate

No functional change intended.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220209105452.1694545-5-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:14:40 +01:00
Emanuele Giuseppe Esposito
a94750d956 block: introduce bdrv_activate
This function is currently just a wrapper for bdrv_invalidate_cache(),
but in future will contain the code of bdrv_co_invalidate_cache() that
has to always be protected by BQL, and leave the rest in the I/O
coroutine.

Replace all bdrv_invalidate_cache() invokations with bdrv_activate().

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220209105452.1694545-4-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:14:40 +01:00
Vladimir Sementsov-Ogievskiy
0c8022876f block: use int64_t instead of int in driver discard 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 discard handlers bytes parameter to int64_t.

The only caller of all updated function is bdrv_co_pdiscard in
block/io.c. It is already prepared to work with 64bit requests, but
pass at most max(bs->bl.max_pdiscard, INT_MAX) to the driver.

Let's look at all updated functions:

blkdebug: all calculations are still OK, thanks to
  bdrv_check_qiov_request().
  both rule_check and bdrv_co_pdiscard are 64bit

blklogwrites: pass to blk_loc_writes_co_log which is 64bit

blkreplay, copy-on-read, filter-compress: pass to bdrv_co_pdiscard, OK

copy-before-write: pass to bdrv_co_pdiscard which is 64bit and to
  cbw_do_copy_before_write which is 64bit

file-posix: one handler calls raw_account_discard() is 64bit and both
  handlers calls raw_do_pdiscard(). Update raw_do_pdiscard, which pass
  to RawPosixAIOData::aio_nbytes, which is 64bit (and calls
  raw_account_discard())

gluster: somehow, third argument of glfs_discard_async is size_t.
  Let's set max_pdiscard accordingly.

iscsi: iscsi_allocmap_set_invalid is 64bit,
  !is_byte_request_lun_aligned is 64bit.
  list.num is uint32_t. Let's clarify max_pdiscard and
  pdiscard_alignment.

mirror_top: pass to bdrv_mirror_top_do_write() which is
  64bit

nbd: protocol limitation. max_pdiscard is alredy set strict enough,
  keep it as is for now.

nvme: buf.nlb is uint32_t and we do shift. So, add corresponding limits
  to nvme_refresh_limits().

preallocate: pass to bdrv_co_pdiscard() which is 64bit.

rbd: pass to qemu_rbd_start_co() which is 64bit.

qcow2: calculations are still OK, thanks to bdrv_check_qiov_request(),
  qcow2_cluster_discard() is 64bit.

raw-format: raw_adjust_offset() is 64bit, bdrv_co_pdiscard too.

throttle: pass to bdrv_co_pdiscard() which is 64bit and to
  throttle_group_co_io_limits_intercept() which is 64bit as well.

test-block-iothread: bytes argument is unused

Great! Now all drivers are prepared to handle 64bit discard requests,
or else have explicit max_pdiscard limits.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-11-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Vladimir Sementsov-Ogievskiy
e75abedab7 block: use int64_t instead of uint64_t in driver write 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 write 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_\(aio\|co\)_pwritev\(_part\)\?'

shows that's there three callers of driver function:

 bdrv_driver_pwritev() and bdrv_driver_pwritev_compressed() in
 block/io.c, both pass int64_t, checked by bdrv_check_qiov_request() to
 be non-negative.

 qcow2_save_vmstate() does bdrv_check_qiov_request().

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

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

shows several callers:

qcow2:
  qcow2_co_truncate() write at most up to @offset, which is checked in
    generic qcow2_co_truncate() by bdrv_check_request().
  qcow2_co_pwritev_compressed_task() pass the request (or part of the
    request) that already went through normal write path, so it should
    be OK

qcow:
  qcow_co_pwritev_compressed() pass int64_t, it's updated by this patch

quorum:
  quorum_co_pwrite_zeroes() pass int64_t and int - OK

throttle:
  throttle_co_pwritev_compressed() pass int64_t, it's updated by this
  patch

vmdk:
  vmdk_co_pwritev_compressed() pass int64_t, it's updated by this
  patch

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-5-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:31 -05:00
Vladimir Sementsov-Ogievskiy
f7ef38dd13 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>
2021-09-29 13:46:31 -05:00
Vladimir Sementsov-Ogievskiy
975da07374 block: drop BlockDriverState::read_only
This variable is just a cache for !(bs->open_flags & BDRV_O_RDWR),
which we have to synchronize everywhere. Let's just drop it and
consistently use bdrv_is_read_only().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210527154056.70294-3-vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-06-02 14:23:20 +02:00
Emanuele Giuseppe Esposito
d8b2e5639a tests/unit/test-block-iothread: fix maybe-uninitialized error on GCC 11
When building qemu with GCC 11, test-block-iothread produces the following
warning:

../tests/unit/test-block-iothread.c:148:11: error: ‘buf’ may be used
uninitialized [-Werror=maybe-uninitialized]

This is caused by buf[512] left uninitialized and passed to
bdrv_save_vmstate() that expects a const uint8_t *, so the compiler
assumes it will be read and expects the parameter to be initialized.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210319112218.49609-1-eesposit@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-03-20 06:17:09 +01:00
Thomas Huth
da668aa15b tests: Move unit tests into a separate directory
The main tests directory still looks very crowded, and it's not
clear which files are part of a unit tests and which belong to
a different test subsystem. Let's clean up the mess and move the
unit tests to a separate directory.

Message-Id: <20210310063314.1049838-1-thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-03-12 15:46:30 +01:00