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* Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into stagingPeter Maydell2018-03-0632-521/+572
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * block: Fix NULL dereference on empty drive errorKevin Wolf2018-03-051-2/+3
| | | | | | | | | | | | | | | | | | | | | | blk_error_action() sends a BLOCK_IO_ERROR QMP event which includes the node name of its root node. If the BlockBackend represents an empty drive, there is no root node, so we should not try to access its node name. Make the field optional in the event and include it only when the BlockBackend isn't empty. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
| * qcow2: Replace align_offset() with ROUND_UP()Alberto Garcia2018-03-026-24/+18Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The align_offset() function is equivalent to the ROUND_UP() macro so there's no need to use the former. The ROUND_UP() name is also a bit more explicit. This patch uses ROUND_UP() instead of the slower QEMU_ALIGN_UP() because align_offset() already requires that the second parameter is a power of two. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20180215131008.5153-1-berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
| * block/ssh: Add basic .bdrv_truncate()Max Reitz2018-03-021-0/+24
| | | | | | | | | | | | | | | | | | | | | | libssh2 does not seem to offer real truncation support, so we can only grow files -- but that is better than nothing. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20180214204915.7980-4-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
| * block/ssh: Make ssh_grow_file() blockingMax Reitz2018-03-021-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At runtime (that is, during a future ssh_truncate()), the SSH session is non-blocking. However, ssh_truncate() (or rather, bdrv_truncate() in general) is not a coroutine, so this resize operation needs to block. For ssh_create(), that is fine, too; the session is never set to non-blocking anyway. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20180214204915.7980-3-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
| * block/ssh: Pull ssh_grow_file() from ssh_create()Max Reitz2018-03-021-8/+22
| | | | | | | | | | | | | | | | | | | | | | If we ever want to offer even rudimentary truncation functionality for ssh, we should put the respective code into a reusable function. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20180214204915.7980-2-mreitz@redhat.com Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
| * qcow2: make qcow2_co_create2() a coroutine_fnStefan Hajnoczi2018-03-021-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | qcow2_create2() calls qemu_co_mutex_lock(). Only a coroutine_fn may call another coroutine_fn. In fact, qcow2_create2 is always called from coroutine context. Rename the function to add the "co" moniker and add coroutine_fn. Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20170705102231.20711-3-stefanha@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * block: rename .bdrv_create() to .bdrv_co_create_opts()Stefan Hajnoczi2018-03-0218-51/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BlockDriver->bdrv_create() has been called from coroutine context since commit 5b7e1542cfa41a281af9629d31cef03704d976e6 ("block: make bdrv_create adopt coroutine"). Make this explicit by renaming to .bdrv_co_create_opts() and add the coroutine_fn annotation. This makes it obvious to block driver authors that they may yield, use CoMutex, or other coroutine_fn APIs. bdrv_co_create is reserved for the QAPI-based version that Kevin is working on. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20170705102231.20711-2-stefanha@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * block: add BlockBackend->in_flight counterStefan Hajnoczi2018-03-021-7/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BlockBackend currently relies on BlockDriverState->in_flight to track requests for blk_drain(). There is a corner case where BlockDriverState->in_flight cannot be used though: blk->root can be NULL when there is no medium. This results in a segfault when the NULL pointer is dereferenced. Introduce a BlockBackend->in_flight counter for aio requests so it works even when blk->root == NULL. Based on a patch by Kevin Wolf <kwolf@redhat.com>. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * block: extract AIO_WAIT_WHILE() from BlockDriverStateStefan Hajnoczi2018-03-021-8/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * block: fix write with zero flag set and iovector providedAnton Nefedov2018-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The normal bdrv_co_pwritev() use is either - BDRV_REQ_ZERO_WRITE clear and iovector provided - BDRV_REQ_ZERO_WRITE set and iovector == NULL while - the flag clear and iovector == NULL is an assertion failure in bdrv_co_do_zero_pwritev() - the flag set and iovector provided is in fact allowed (the flag prevails and zeroes are written) However the alignment logic does not support the latter case so the padding areas get overwritten with zeroes. Currently, general functions like bdrv_rw_co() do provide iovector regardless of flags. So, keep it supported and use bdrv_co_do_zero_pwritev() alignment for it which also makes the code a bit more obvious anyway. Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * block: Drop unused .bdrv_co_get_block_status()Eric Blake2018-03-021-40/+10Star
| | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Now that all drivers have been updated to provide the byte-based .bdrv_co_block_status(), we can delete the sector-based interface. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * vvfat: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-9/+7Star
| | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the vvfat driver accordingly. Note that we can rely on the block driver having already clamped limits to our block size, and simplify accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * vpc: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-22/+23
| | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the vpc driver accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * vmdk: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-24/+14Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the vmdk driver accordingly. Drop the now-unused vmdk_find_index_in_cluster(). Also, fix a pre-existing bug: if find_extent() fails (unlikely, since the block layer did a bounds check), then we must return a failure, rather than 0. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * vdi: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-20/+13Star
| | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the vdi driver accordingly. Note that the TODO is already covered (the block layer guarantees bounds of its requests), and that we can remove the now-unused s->block_sectors. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * vdi: Avoid bitrot of debugging codeEric Blake2018-03-021-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | Rework the debug define so that we always get -Wformat checking, even when debugging is disabled. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * sheepdog: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-13/+13
| | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the sheepdog driver accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * raw: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-8/+8
| | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the raw driver accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * qed: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-52/+24Star
| | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the qed driver accordingly, taking the opportunity to inline qed_is_allocated_cb() into its lone caller (the callback used to be important, until we switched qed to coroutines). There is no intent to optimize based on the want_zero flag for this format. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * qcow2: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the qcow2 driver accordingly. For now, we are ignoring the 'want_zero' hint. However, it should be relatively straightforward to honor the hint as a way to return larger *pnum values when we have consecutive clusters with the same data/zero status but which differ only in having non-consecutive mappings. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * qcow: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-11/+16
| | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the qcow driver accordingly. There is no intent to optimize based on the want_zero flag for this format. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * parallels: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-7/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the parallels driver accordingly. Note that the internal function block_status() is still sector-based, because it is still in use by other sector-based functions; but that's okay because request_alignment is 512 as a result of those functions. For now, no optimizations are added based on the mapping hint. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * null: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-11/+12
| | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the null driver accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * iscsi: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-36/+33Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the iscsi driver accordingly. In this case, it is handy to teach iscsi_co_block_status() to handle a NULL map and file parameter, even though the block layer passes non-NULL values, because we also call the function directly. For now, there are no optimizations done based on the want_zero flag. We can also make the simplification of asserting that the block layer passed in aligned values. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * iscsi: Switch iscsi_allocmap_update() to byte-basedEric Blake2018-03-021-46/+44Star
| | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually converting to byte-based interfaces, as they are easier to reason about than sector-based. Convert all uses of the allocmap (no semantic change). Callers that already had bytes available are simpler, and callers that now scale to bytes will be easier to switch to byte-based in the future. Signed-off-by: Eric Blake <eblake@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * iscsi: Switch cluster_sectors to byte-basedEric Blake2018-03-021-21/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually converting to byte-based interfaces, as they are easier to reason about than sector-based. Convert all uses of the cluster size in sectors, along with adding assertions that we are not dividing by zero. Improve some comment grammar while in the area. Signed-off-by: Eric Blake <eblake@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * gluster: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-36/+34Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the gluster driver accordingly. In want_zero mode, we continue to report fine-grained hole information (the caller wants as much mapping detail as possible); but when not in that mode, the caller prefers larger *pnum and merely cares about what offsets are allocated at this layer, rather than where the holes live. Since holes still read as zeroes at this layer (rather than deferring to a backing layer), we can take the shortcut of skipping find_allocation(), and merely state that all bytes are allocated. We can also drop redundant bounds checks that are already guaranteed by the block layer. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * file-posix: Switch to .bdrv_co_block_status()Eric Blake2018-03-021-34/+30Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the file protocol driver accordingly. In want_zero mode, we continue to report fine-grained hole information (the caller wants as much mapping detail as possible); but when not in that mode, the caller prefers larger *pnum and merely cares about what offsets are allocated at this layer, rather than where the holes live. Since holes still read as zeroes at this layer (rather than deferring to a backing layer), we can take the shortcut of skipping lseek(), and merely state that all bytes are allocated. We can also drop redundant bounds checks that are already guaranteed by the block layer. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * block: Switch passthrough drivers to .bdrv_co_block_status()Eric Blake2018-03-025-28/+34
| | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Update the generic helpers, and all passthrough clients (blkdebug, commit, mirror, throttle) accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * nvme: Drop pointless .bdrv_co_get_block_status()Eric Blake2018-03-021-14/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit bdd6a90 has a bug: drivers should never directly set BDRV_BLOCK_ALLOCATED, but only io.c should do that (as needed). Instead, drivers should report BDRV_BLOCK_DATA if it knows that data comes from this BDS. But let's look at the bigger picture: semantically, the nvme driver is similar to the nbd, null, and raw drivers (no backing file, all data comes from this BDS). But while two of those other drivers have to supply the callback (null because it can special-case BDRV_BLOCK_ZERO, raw because it can special-case a different offset), in this case the block layer defaults are good enough without the callback at all (similar to nbd). So, fix the bug by deletion ;) Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
| * block: Add .bdrv_co_block_status() callbackEric Blake2018-03-021-9/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are gradually moving away from sector-based interfaces, towards byte-based. Now that the block layer exposes byte-based allocation, it's time to tackle the drivers. Add a new callback that operates on as small as byte boundaries. Subsequent patches will then update individual drivers, then finally remove .bdrv_co_get_block_status(). The new code also passes through the 'want_zero' hint, which will allow subsequent patches to further optimize callers that only care about how much of the image is allocated (want_zero is false), rather than full details about runs of zeroes and which offsets the allocation actually maps to (want_zero is true). As part of this effort, fix another part of the documentation: the claim in commit 4c41cb4 that BDRV_BLOCK_ALLOCATED is short for 'DATA || ZERO' is a lie at the block layer (see commit e88ae2264), even though it is how the bit is computed from the driver layer. After all, there are intentionally cases where we return ZERO but not ALLOCATED at the block layer, when we know that a read sees zero because the backing file is too short. Note that the driver interface is thus slightly different than the public interface with regards to which bits will be set, and what guarantees are provided on input. We also add an assertion that any driver using the new callback will make progress (the only time pnum will be 0 is if the block layer already handled an out-of-bounds request, or if there is an error); the old driver interface did not provide this guarantee, which could lead to some inf-loops in drastic corner-case failures. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* | qapi: Empty out qapi-schema.jsonMarkus Armbruster2018-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The previous commit improved compile time by including less of the generated QAPI headers. This is impossible for stuff defined directly in qapi-schema.json, because that ends up in headers that that pull in everything. Move everything but include directives from qapi-schema.json to new sub-module qapi/misc.json, then include just the "misc" shard where possible. It's possible everywhere, except: * monitor.c needs qmp-command.h to get qmp_init_marshal() * monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need qapi-event.h to get enum QAPIEvent Perhaps we'll get rid of those some other day. Adding a type to qapi/migration.json now recompiles some 120 instead of 2300 out of 5100 objects. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-25-armbru@redhat.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
* | Include less of the generated modular QAPI headersMarkus Armbruster2018-03-0211-14/+13Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In my "build everything" tree, a change to the types in qapi-schema.json triggers a recompile of about 4800 out of 5100 objects. The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h, qapi-types.h. Each of these headers still includes all its shards. Reduce compile time by including just the shards we actually need. To illustrate the benefits: adding a type to qapi/migration.json now recompiles some 2300 instead of 4800 objects. The next commit will improve it further. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-24-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
* | Include qapi/qmp/qerror.h exactly where neededMarkus Armbruster2018-03-021-1/+0Star
|/ | | | | | | | Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-2-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* nbd: Honor server's advertised minimum block sizeEric Blake2018-03-012-3/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 79ba8c98 (v2.7) changed the setting of request_alignment to occur only during bdrv_refresh_limits(), rather than at at bdrv_open() time; but at the time, NBD was unaffected, because it still used sector-based callbacks, so the block layer defaulted NBD to use 512 request_alignment. Later, commit 70c4fb26 (also v2.7) changed NBD to use byte-based callbacks, without setting request_alignment. This resulted in NBD using request_alignment of 1, which works great when the server supports it (as is the case for qemu-nbd), but falls apart miserably if the server requires alignment (but only if qemu actually sends a sub-sector request; qemu-io can do it, but most qemu operations still perform on sectors or larger). Even later, the NBD protocol was updated to document that clients should learn the server's minimum alignment during NBD_OPT_GO; and recommended that clients should assume a minimum size of 512 unless the server understands NBD_OPT_GO and replied with a smaller size. Commit 081dd1fe (v2.10) attempted to do that, by assigning request_alignment to whatever was learned from the server; but it has two flaws: the assignment is done during bdrv_open() so it gets unconditionally wiped out back to 1 during any later bdrv_refresh_limits(); and the code is not using a default of 512 when the server did not report a minimum size. Fix these issues by moving the assignment to request_alignment to the right function, and by using a sane default when the server does not advertise a minimum size. CC: qemu-stable@nongnu.org Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20180215032905.27146-1-eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com>
* block/nvme: fix Coverity reportsPaolo Bonzini2018-03-011-3/+7
| | | | | | | | | | | | 1) string not null terminated in sysfs_find_group_file 2) NULL pointer dereference and dead local variable in nvme_init. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Message-Id: <20180213015240.9352-1-famz@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
* qcow2: Allow configuring the L2 slice sizeAlberto Garcia2018-02-133-11/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the code is ready to handle L2 slices we can finally add an option to allow configuring their size. An L2 slice is the portion of an L2 table that is read by the qcow2 cache. Until now the cache was always reading full L2 tables, and since the L2 table size is equal to the cluster size this was not very efficient with large clusters. Here's a more detailed explanation of why it makes sense to have smaller cache entries in order to load L2 data: https://lists.gnu.org/archive/html/qemu-block/2017-09/msg00635.html This patch introduces a new command-line option to the qcow2 driver named l2-cache-entry-size (cf. l2-cache-size). The cache entry size has the same restrictions as the cluster size: it must be a power of two and it has the same range of allowed values, with the additional requirement that it must not be larger than the cluster size. The L2 cache entry size (L2 slice size) remains equal to the cluster size for now by default, so this feature must be explicitly enabled. Although my tests show that 4KB slices consistently improve performance and give the best results, let's wait and make more tests with different cluster sizes before deciding on an optimal default. Now that the cache entry size is not necessarily equal to the cluster size we need to reflect that in the MIN_L2_CACHE_SIZE documentation. That minimum value is a requirement of the COW algorithm: we need to read two L2 slices (and not two L2 tables) in order to do COW, see l2_allocate() for the actual code. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: c73e5611ff4a9ec5d20de68a6c289553a13d2354.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Rename l2_table in count_cow_clusters()Alberto Garcia2018-02-131-2/+2
| | | | | | | | | | | | This function doesn't need any changes to support L2 slices, but since it's now dealing with slices intead of full tables, the l2_table variable is renamed for clarity. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 6107001fc79e6739242f1de7d191375e4f130aac.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Rename l2_table in count_contiguous_clusters_unallocated()Alberto Garcia2018-02-131-3/+3
| | | | | | | | | | | | This function doesn't need any changes to support L2 slices, but since it's now dealing with slices instead of full tables, the l2_table variable is renamed for clarity. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 78bcc54bc632574dd0b900a77a00a1b6ffc359e6.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Rename l2_table in count_contiguous_clusters()Alberto Garcia2018-02-131-4/+4
| | | | | | | | | | | | This function doesn't need any changes to support L2 slices, but since it's now dealing with slices intead of full tables, the l2_table variable is renamed for clarity. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 812b0c3505bb1687e51285dccf1a94f0cecb1f74.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Rename l2_table in qcow2_alloc_compressed_cluster_offset()Alberto Garcia2018-02-131-8/+8
| | | | | | | | | | | | This function doesn't need any changes to support L2 slices, but since it's now dealing with slices instead of full tables, the l2_table variable is renamed for clarity. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 0c5d4b9bf163aa3b49ec19cc512a50d83563f2ad.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Update qcow2_truncate() to support L2 slicesAlberto Garcia2018-02-131-3/+3
| | | | | | | | | | | | | | | The qcow2_truncate() code is mostly independent from whether we're using L2 slices or full L2 tables, but in full and falloc preallocation modes new L2 tables are allocated using qcow2_alloc_cluster_link_l2(). Therefore the code needs to be modified to ensure that all nb_clusters that are processed in each call can be allocated with just one L2 slice. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: 1fd7d272b5e7b66254a090b74cf2bed1cc334c0e.1517840877.git.berto@igalia.com Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Update expand_zero_clusters_in_l1() to support L2 slicesAlberto Garcia2018-02-131-23/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | expand_zero_clusters_in_l1() expands zero clusters as a necessary step to downgrade qcow2 images to a version that doesn't support metadata zero clusters. This function takes an L1 table (which may or may not be active) and iterates over all its L2 tables looking for zero clusters. Since we'll be loading L2 slices instead of full tables we need to add an extra loop that iterates over all slices of each L2 table, and we should also use the slice size when allocating the buffer used when the L1 table is not active. This function doesn't need any additional changes so apart from that this patch simply updates the variable name from l2_table to l2_slice. Finally, and since we have to touch the bdrv_read() / bdrv_write() calls anyway, this patch takes the opportunity to replace them with the byte-based bdrv_pread() / bdrv_pwrite(). Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 43590976f730501688096cff103f2923b72b0f32.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Prepare expand_zero_clusters_in_l1() for adding L2 slice supportAlberto Garcia2018-02-131-91/+96
| | | | | | | | | | | | | | | | | | | | | Adding support for L2 slices to expand_zero_clusters_in_l1() needs (among other things) an extra loop that iterates over all slices of each L2 table. Putting all changes in one patch would make it hard to read because all semantic changes would be mixed with pure indentation changes. To make things easier this patch simply creates a new block and changes the indentation of all lines of code inside it. Thus, all modifications in this patch are cosmetic. There are no semantic changes and no variables are renamed yet. The next patch will take care of that. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: c2ae9f31ed5b6e591477ad4654448badd1c89d73.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Read refcount before L2 table in expand_zero_clusters_in_l1()Alberto Garcia2018-02-131-6/+6
| | | | | | | | | | | | | | | | At the moment it doesn't really make a difference whether we call qcow2_get_refcount() before of after reading the L2 table, but if we want to support L2 slices we'll need to read the refcount first. This patch simply changes the order of those two operations to prepare for that. The patch with the actual semantic changes will be easier to read because of this. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 947a91d934053a2dbfef979aeb9568f57ef57c5d.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Update qcow2_update_snapshot_refcount() to support L2 slicesAlberto Garcia2018-02-131-14/+18
| | | | | | | | | | | | | | | | | qcow2_update_snapshot_refcount() increases the refcount of all clusters of a given snapshot. In order to do that it needs to load all its L2 tables and iterate over their entries. Since we'll be loading L2 slices instead of full tables we need to add an extra loop that iterates over all slices of each L2 table. This function doesn't need any additional changes so apart from that this patch simply updates the variable name from l2_table to l2_slice. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: 5f4db199b9637f4833b58487135124d70add8cf0.1517840877.git.berto@igalia.com Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Prepare qcow2_update_snapshot_refcount() for adding L2 slice supportAlberto Garcia2018-02-131-69/+75
| | | | | | | | | | | | | | | | | | | | | Adding support for L2 slices to qcow2_update_snapshot_refcount() needs (among other things) an extra loop that iterates over all slices of each L2 table. Putting all changes in one patch would make it hard to read because all semantic changes would be mixed with pure indentation changes. To make things easier this patch simply creates a new block and changes the indentation of all lines of code inside it. Thus, all modifications in this patch are cosmetic. There are no semantic changes and no variables are renamed yet. The next patch will take care of that. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 8ffaa5e55bd51121f80e498f4045b64902a94293.1517840877.git.berto@igalia.com Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Update zero_single_l2() to support L2 slicesAlberto Garcia2018-02-131-14/+14
| | | | | | | | | | | | | | | zero_single_l2() limits the number of clusters to be zeroed to the amount that fits inside an L2 table. Since we'll be loading L2 slices instead of full tables we need to update that limit. The function is renamed to zero_in_l2_slice() for clarity. Apart from that, this function doesn't need any additional changes, so this patch simply updates the variable name from l2_table to l2_slice. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: ebc16e7e79fa6969d8975ef487d679794de4fbcc.1517840877.git.berto@igalia.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* qcow2: Update discard_single_l2() to support L2 slicesAlberto Garcia2018-02-131-16/+16
| | | | | | | | | | | | | | | discard_single_l2() limits the number of clusters to be discarded to the amount that fits inside an L2 table. Since we'll be loading L2 slices instead of full tables we need to update that limit. The function is renamed to discard_in_l2_slice() for clarity. Apart from that, this function doesn't need any additional changes, so this patch simply updates the variable name from l2_table to l2_slice. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: 1cb44a5b68be5334cb01b97a3db3a3c5a43396e5.1517840877.git.berto@igalia.com Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
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