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* blockjob: refactor backup_start as backup_job_createJohn Snow2016-11-151-11/+12
| | | | | | | | | | | | | | | | | | | | | Refactor backup_start as backup_job_create, which only creates the job, but does not automatically start it. The old interface, 'backup_start', is not kept in favor of limiting the number of nearly-identical interfaces that would have to be edited to keep up with QAPI changes in the future. Callers that wish to synchronously start the backup_block_job can instead just call block_job_start immediately after calling backup_job_create. Transactions are updated to use the new interface, calling block_job_start only during the .commit phase, which helps prevent race conditions where jobs may finish before we even finish building the transaction. This may happen, for instance, during empty block backup jobs. Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1478587839-9834-6-git-send-email-jsnow@redhat.com Signed-off-by: Jeff Cody <jcody@redhat.com>
* blockjob: centralize QMP event emissionsJohn Snow2016-11-011-13/+4Star
| | | | | | | | | | | | | | There's no reason to leave this to blockdev; we can do it in blockjobs directly and get rid of an extra callback for most users. All non-internal events, even those created outside of QMP, will consistently emit events. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Message-id: 1477584421-1399-5-git-send-email-jsnow@redhat.com Signed-off-by: Jeff Cody <jcody@redhat.com>
* Replication/Blockjobs: Create replication jobs as internalJohn Snow2016-11-011-2/+7
| | | | | | | | | | | Bubble up the internal interface to commit and backup jobs, then switch replication tasks over to using this methodology. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Message-id: 1477584421-1399-4-git-send-email-jsnow@redhat.com Signed-off-by: Jeff Cody <jcody@redhat.com>
* block: only call aio_poll on the current thread's AioContextPaolo Bonzini2016-10-281-0/+17
| | | | | | | | | | | | | | | | | | aio_poll is not thread safe; for example bdrv_drain can hang if the last in-flight I/O operation is completed in the I/O thread after the main thread has checked bs->in_flight. The bug remains latent as long as all of it is called within aio_context_acquire/aio_context_release, but this will change soon. To fix this, if bdrv_drain is called from outside the I/O thread, signal the main AioContext through a dummy bottom half. The event loop then only runs in the I/O thread. Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1477565348-5458-18-git-send-email-pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
* block: add BDS field to count in-flight requestsPaolo Bonzini2016-10-281-4/+6
| | | | | | | | | | | | | | | | Unlike tracked_requests, this field also counts throttled requests, and remains non-zero if an AIO operation needs a BH to be "really" completed. With this change, it is no longer necessary to have a dummy BdrvTrackedRequest for requests that are never serialising, and it is no longer necessary to poll the AioContext once after bdrv_requests_pending(bs) returns false. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-Id: <1477565348-5458-5-git-send-email-pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
* block: Introduce .bdrv_co_ioctl() driver callbackKevin Wolf2016-10-271-0/+2
| | | | | | | This allows drivers to implement ioctls in a coroutine-based way. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* block: mirror: fix wrong comment of mirror_startYaowei Bai2016-09-281-1/+1
| | | | | | | | | | Obviously, we should write to '@target'. Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Reviewed-by: Xiubo Li <lixiubo@cmss.chinamobile.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1473851019-7005-2-git-send-email-baiyaowei@cmss.chinamobile.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* Remove unused function declarationsLadi Prosek2016-09-151-9/+0Star
| | | | | | | | Unused function declarations were found using a simple gcc plugin and manually verified by grepping the sources. Signed-off-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
* mirror: auto complete active commitWen Congyang2016-09-131-1/+2
| | | | | | | | | | | Auto complete mirror job in background to prevent from blocking synchronously Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com> Signed-off-by: Wang WeiWei <wangww.fnst@cn.fujitsu.com> Message-id: 1469602913-20979-7-git-send-email-xiecl.fnst@cn.fujitsu.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* drive-backup: added support for data compressionPavel Butsykin2016-09-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | The idea is simple - backup is "written-once" data. It is written block by block and it is large enough. It would be nice to save storage space and compress it. The patch adds a flag to the qmp/hmp drive-backup command which enables block compression. Compression should be implemented in the format driver to enable this feature. There are some limitations of the format driver to allow compressed writes. We can write data only once. Though for backup this is perfectly fine. These limitations are maintained by the driver and the error will be reported if we are doing something wrong. Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Jeff Cody <jcody@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: John Snow <jsnow@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: remove BlockDriver.bdrv_write_compressedPavel Butsykin2016-09-051-3/+0Star
| | | | | | | | | | | | | | | | | | There are no block drivers left that implement the old .bdrv_write_compressed interface, so it can be removed. Also now we have no need to use the bdrv_pwrite_compressed function and we can remove it entirely. Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Jeff Cody <jcody@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: John Snow <jsnow@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/io: reuse bdrv_co_pwritev() for write compressedPavel Butsykin2016-09-051-0/+3
| | | | | | | | | | | | | | | | | | | For bdrv_pwrite_compressed() it looks like most of the code creating coroutine is duplicated in bdrv_prwv_co(). So we can just add a flag (BDRV_REQ_WRITE_COMPRESSED) and use bdrv_prwv_co() as a generic one. In the end we get coroutine oriented function for write compressed by using bdrv_co_pwritev/blk_co_pwritev with BDRV_REQ_WRITE_COMPRESSED flag. Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Jeff Cody <jcody@redhat.com> CC: Markus Armbruster <armbru@redhat.com> CC: Eric Blake <eblake@redhat.com> CC: John Snow <jsnow@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: fix deadlock in bdrv_co_flushEvgeny Yakovlev2016-08-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following commit commit 3ff2f67a7c24183fcbcfe1332e5223ac6f96438c Author: Evgeny Yakovlev <eyakovlev@virtuozzo.com> Date: Mon Jul 18 22:39:52 2016 +0300 block: ignore flush requests when storage is clean has introduced a regression. There is a problem that it is still possible for 2 requests to execute in non sequential fashion and sometimes this results in a deadlock when bdrv_drain_one/all are called for BDS with such stalled requests. 1. Current flushed_gen and flush_started_gen is 1. 2. Request 1 enters bdrv_co_flush to with write_gen 1 (i.e. the same as flushed_gen). It gets past flushed_gen != flush_started_gen and sets flush_started_gen to 1 (again, the same it was before). 3. Request 1 yields somewhere before exiting bdrv_co_flush 4. Request 2 enters bdrv_co_flush with write_gen 2. It gets past flushed_gen != flush_started_gen and sets flush_started_gen to 2. 5. Request 2 runs to completion and sets flushed_gen to 2 6. Request 1 is resumed, runs to completion and sets flushed_gen to 1. However flush_started_gen is now 2. From here on out flushed_gen is always != to flush_started_gen and all further requests will wait on flush_queue. This change replaces flush_started_gen with an explicitly tracked active flush request. Signed-off-by: Evgeny Yakovlev <eyakovlev@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> Message-id: 1471457214-3994-2-git-send-email-den@openvz.org CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Fam Zheng <famz@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Cater to iscsi with non-power-of-2 discardEric Blake2016-08-031-17/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dell Equallogic iSCSI SANs have a very unusual advertised geometry: $ iscsi-inq -e 1 -c $((0xb0)) iscsi://XXX/0 wsnz:0 maximum compare and write length:1 optimal transfer length granularity:0 maximum transfer length:0 optimal transfer length:0 maximum prefetch xdread xdwrite transfer length:0 maximum unmap lba count:30720 maximum unmap block descriptor count:2 optimal unmap granularity:30720 ugavalid:1 unmap granularity alignment:0 maximum write same length:30720 which says that both the maximum and the optimal discard size is 15M. It is not immediately apparent if the device allows discard requests not aligned to the optimal size, nor if it allows discards at a finer granularity than the optimal size. I tried to find details in the SCSI Commands Reference Manual Rev. A on what valid values of maximum and optimal sizes are permitted, but while that document mentions a "Block Limits VPD Page", I couldn't actually find documentation of that page or what values it would have, or if a SCSI device has an advertisement of its minimal unmap granularity. So it is not obvious to me whether the Dell Equallogic device is compliance with the SCSI specification. Fortunately, it is easy enough to support non-power-of-2 sizing, even if it means we are less efficient than truly possible when targetting that device (for example, it means that we refuse to unmap anything that is not a multiple of 15M and aligned to a 15M boundary, even if the device truly does support a smaller granularity where unmapping actually works). Reported-by: Peter Lieven <pl@kamp.de> Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1469129688-22848-5-git-send-email-eblake@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into ↵Peter Maydell2016-07-211-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | staging Pull request v2: * Resolved merge conflict with block/iscsi.c [Peter] # gpg: Signature made Wed 20 Jul 2016 17:20:52 BST # gpg: using RSA key 0x9CA4ABB381AB73C8 # gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" # gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>" # Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8 * remotes/stefanha/tags/block-pull-request: (25 commits) raw_bsd: Convert to byte-based interface nbd: Convert to byte-based interface block: Kill .bdrv_co_discard() sheepdog: Switch .bdrv_co_discard() to byte-based raw_bsd: Switch .bdrv_co_discard() to byte-based qcow2: Switch .bdrv_co_discard() to byte-based nbd: Switch .bdrv_co_discard() to byte-based iscsi: Switch .bdrv_co_discard() to byte-based gluster: Switch .bdrv_co_discard() to byte-based blkreplay: Switch .bdrv_co_discard() to byte-based block: Add .bdrv_co_pdiscard() driver callback block: Convert .bdrv_aio_discard() to byte-based rbd: Switch rbd_start_aio() to byte-based raw-posix: Switch paio_submit() to byte-based block: Convert BB interface to byte-based discards block: Convert bdrv_aio_discard() to byte-based block: Switch BlockRequest to byte-based block: Convert bdrv_discard() to byte-based block: Convert bdrv_co_discard() to byte-based iscsi: Rely on block layer to break up large requests ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Conflicts: block/gluster.c
| * block: Kill .bdrv_co_discard()Eric Blake2016-07-201-2/+0Star
| | | | | | | | | | | | | | | | | | | | | | Now that all drivers have a byte-based .bdrv_co_pdiscard(), we no longer need to worry about the sector-based version. We can also relax our minimum alignment to 1 for drivers that support it. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-18-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
| * block: Add .bdrv_co_pdiscard() driver callbackEric Blake2016-07-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's enough drivers with a sector-based callback that it will be easier to switch one at a time. This patch adds a byte-based callback, and then after all drivers are swapped, we'll drop the sector-based callback. [checkpatch doesn't like the space after coroutine_fn in block_int.h, but it's consistent with the rest of the file] Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-10-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
| * block: Convert .bdrv_aio_discard() to byte-basedEric Blake2016-07-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | Another step towards byte-based interfaces everywhere. Replace the sector-based driver callback .bdrv_aio_discard() with a new byte-based .bdrv_aio_pdiscard(). Only raw-posix and RBD drivers are affected, so it was not worth splitting into multiple patches. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1468624988-423-9-git-send-email-eblake@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* | dirty-bitmap: operate with int64_t amountDenis V. Lunev2016-07-191-1/+1
|/ | | | | | | | | | | | | | | | | Underlying HBitmap operates even with uint64_t. Thus this change is safe. This would be useful f.e. to mark entire bitmap dirty in one call. Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1468503209-19498-2-git-send-email-den@openvz.org CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> CC: Jeff Cody <jcody@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com>
* block: ignore flush requests when storage is cleanEvgeny Yakovlev2016-07-191-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some guests (win2008 server for example) do a lot of unnecessary flushing when underlying media has not changed. This adds additional overhead on host when calling fsync/fdatasync. This change introduces a write generation scheme in BlockDriverState. Current write generation is checked against last flushed generation to avoid unnessesary flushes. The problem with excessive flushing was found by a performance test which does parallel directory tree creation (from 2 processes). Results improved from 0.424 loops/sec to 0.432 loops/sec. Each loop creates 10^3 directories with 10 files in each. This affected some blkdebug testcases that were expecting error logs from failure-injected flushes which are now skipped entirely (tests 026 071 089). This also affects the performance of block jobs and thus BLOCK_JOB_READY events for driver-mirror and active block-commit commands now arrives faster, before QMP send successfully returns to caller (tests 141 144). Signed-off-by: Evgeny Yakovlev <eyakovlev@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1468870792-7411-5-git-send-email-den@openvz.org CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Fam Zheng <famz@redhat.com> CC: John Snow <jsnow@redhat.com> Signed-off-by: John Snow <jsnow@redhat.com>
* commit: Add 'job-id' parameter to 'block-commit'Alberto Garcia2016-07-131-6/+10
| | | | | | | | | | This patch adds a new optional 'job-id' parameter to 'block-commit', allowing the user to specify the ID of the block job to be created. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* stream: Add 'job-id' parameter to 'block-stream'Alberto Garcia2016-07-131-4/+6
| | | | | | | | | | | | This patch adds a new optional 'job-id' parameter to 'block-stream', allowing the user to specify the ID of the block job to be created. The HMP 'block_stream' command remains unchanged. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* backup: Add 'job-id' parameter to 'blockdev-backup' and 'drive-backup'Alberto Garcia2016-07-131-3/+5
| | | | | | | | | | | | | This patch adds a new optional 'job-id' parameter to 'blockdev-backup' and 'drive-backup', allowing the user to specify the ID of the block job to be created. The HMP 'drive_backup' command remains unchanged. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* mirror: Add 'job-id' parameter to 'blockdev-mirror' and 'drive-mirror'Alberto Garcia2016-07-131-2/+4
| | | | | | | | | | | | | This patch adds a new optional 'job-id' parameter to 'blockdev-mirror' and 'drive-mirror', allowing the user to specify the ID of the block job to be created. The HMP 'drive_mirror' command remains unchanged. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* stream: Fix prototype of stream_start()Alberto Garcia2016-07-131-5/+6
| | | | | | | | | | | | | | | | 'stream-start' has a parameter called 'backing-file', which is the string to be written to bs->backing when the job finishes. In the stream_start() implementation it is called 'backing_file_str', but it the prototype in the header file it is called 'base_id'. This patch fixes it so the name is the same in both cases and is consistent with other cases (like commit_start()). Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Convert bdrv_co_preadv/pwritev to BdrvChildKevin Wolf2016-07-051-2/+2
| | | | | | | | | | | | | | | | | | | This is the final patch for converting the common I/O path to take a BdrvChild parameter instead of BlockDriverState. The completion of this conversion means that all users that perform I/O on an image need to actually hold a reference (in the form of BdrvChild, possible as part of a BlockBackend) to that image. This also protects against inconsistent use of BlockBackend vs. BlockDriverState functions because direct use of a BlockDriverState isn't possible any more and blk->root is private for block-backends.c. In addition, we can now distinguish different users in the I/O path, and the future op blockers work is going to add assertions based on permissions stored in BdrvChild. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Use bool as appropriate for BDS membersEric Blake2016-07-051-6/+7
| | | | | | | | | | Using int for values that are only used as booleans is confusing. While at it, rearrange a couple of members so that all the bools are contiguous. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Move request_alignment into BlockLimitEric Blake2016-07-051-9/+13
| | | | | | | | | | | | It makes more sense to have ALL block size limit constraints in the same struct. Improve the documentation while at it. Simplify a couple of conditionals, now that we have audited and documented that request_alignment is always non-zero. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Switch discard length bounds to byte-basedEric Blake2016-07-051-5/+11
| | | | | | | | | | | | | | | | | | | | | | Sector-based limits are awkward to think about; in our on-going quest to move to byte-based interfaces, convert max_discard and discard_alignment. Rename them, using 'pdiscard' as an aid to track which remaining discard interfaces need conversion, and so that the compiler will help us catch the change in semantics across any rebased code. The BlockLimits type is now completely byte-based; and in iscsi.c, sector_limits_lun2qemu() is no longer needed. pdiscard_alignment is made unsigned (we use power-of-2 alignments as bitmasks, where unsigned is easier to think about) while leaving max_pdiscard signed (since we still have an 'int' interface); this is comparable to what commit cf081fc did for write zeroes limits. We may later want to make everything an unsigned 64-bit limit - but that requires a bigger code audit. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Wording tweaks to write zeroes limitsEric Blake2016-07-051-2/+5
| | | | | | | | | | Improve the documentation of the write zeroes limits, to mention additional constraints that drivers should observe. Worth squashing into commit cf081fca, if that hadn't been pushed already :) Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Switch transfer length bounds to byte-basedEric Blake2016-07-051-5/+8
| | | | | | | | | | | | | | | | | | Sector-based limits are awkward to think about; in our on-going quest to move to byte-based interfaces, convert max_transfer_length and opt_transfer_length. Rename them (dropping the _length suffix) so that the compiler will help us catch the change in semantics across any rebased code, and improve the documentation. Use unsigned values, so that we don't have to worry about negative values and so that bit-twiddling is easier; however, we are still constrained by 2^31 of signed int in most APIs. When a value comes from an external source (iscsi and raw-posix), sanitize the results to ensure that opt_transfer is a power of 2. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: use safe iteration over AioContext notifiersStefan Hajnoczi2016-06-201-0/+2
| | | | | | | | | | | | | | | | | | | | It's possible that an AioContext notifier user was close to finishing when .detach_aio_context() or .attached_aio_context() is called. In that case they may call bdrv_remove_aio_context_notifier() during the callback. Use safe iteration to avoid crashing when the notifier list is modified during iteration. We must not only handle the case where the current aio notifier is removed during a callback but also the one where any other aio notifier is removed. The next patch adds an AioContext notifier for block jobs and they really could be terminating just as .detach_aio_context() is invoked. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 1466096189-6477-6-git-send-email-stefanha@redhat.com
* block/mirror: Fix target backing BDSMax Reitz2016-06-161-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: Remove bs->zero_beyond_eofKevin Wolf2016-06-161-3/+0Star
| | | | | | | | | It is always true for open images now. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Make bdrv_load/save_vmstate coroutine_fnsKevin Wolf2016-06-161-4/+6
| | | | | | | | | | This allows drivers to share code between normal I/O and vmstate accesses. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Make .bdrv_load_vmstate() vectoredKevin Wolf2016-06-161-2/+2
| | | | | | | | | This brings it in line with .bdrv_save_vmstate(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Kill bdrv_co_write_zeroes()Eric Blake2016-06-081-2/+0Star
| | | | | | | | | Now that all drivers have been converted to a byte interface, we no longer need a sector interface. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Add .bdrv_co_pwrite_zeroes()Eric Blake2016-06-081-1/+3
| | | | | | | | | | Update bdrv_co_do_write_zeroes() to be byte-based, and select between the new byte-based bdrv_co_pwrite_zeroes() or the old bdrv_co_write_zeroes(). The next patches will convert drivers, then remove the old interface. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Track write zero limits in bytesEric Blake2016-06-081-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Another step towards removing sector-based interfaces: convert the maximum write and minimum alignment values from sectors to bytes. Rename the variables to let the compiler check that all users are converted to the new semantics. The maximum remains an int as long as BDRV_REQUEST_MAX_SECTORS is constrained by INT_MAX (this means that we can't even support a 2G write_zeroes, but just under it) - changing operation lengths to unsigned or to 64-bits is a much bigger audit, and debatable if we even want to do it (since at the core, a 32-bit platform will still have ssize_t as its underlying limit on write()). Meanwhile, alignment is changed to 'uint32_t', since it makes no sense to have an alignment larger than the maximum write, and less painful to use an unsigned type with well-defined behavior in bit operations than to have to worry about what happens if a driver mistakenly supplies a negative alignment. Add an assert that no one was trying to use sectors to get a write zeroes larger than 2G, and therefore that a later conversion to bytes won't be impacted by keeping the limit at 32 bits. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Fix reconfiguring graph with drained nodesKevin Wolf2016-05-251-1/+2
| | | | | | | | | | | | | | | | | When changing the BlockDriverState that a BdrvChild points to while the node is currently drained, we must call the .drained_end() parent callback. Conversely, when this means attaching a new node that is already drained, we need to call .drained_begin(). bdrv_root_attach_child() takes now an opaque parameter, which is needed because the callbacks must also be called if we're attaching a new child to the BlockBackend when the root node is already drained, and they need a way to identify the BlockBackend. Previously, child->opaque was set too late and the callbacks would still see it as NULL. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
* block: Remove BlockDriverState.blkKevin Wolf2016-05-191-2/+1Star
| | | | | | | | | | | | | This patch removes the remaining users of bs->blk, which will allow us to have multiple BBs on top of a single BDS. In the meantime, all checks that are currently in place to prevent the user from creating such setups can be switched to bdrv_has_blk() instead of accessing BDS.blk. Future patches can allow them and e.g. enable users to mirror to a block device that already has a BlockBackend on it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
* block: User BdrvChild callback for device nameKevin Wolf2016-05-191-0/+5
| | | | | | | | | In order to get rid of bs->blk for bdrv_get_device_name() and bdrv_get_device_or_node_name(), ask all parents for their name and simply pick the first one. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
* block: Use BdrvChild callbacks for change_media/resizeKevin Wolf2016-05-191-1/+3
| | | | | | | | | | We want to get rid of BlockDriverState.blk in order to allow multiple BlockBackends per BDS. Converting the device callbacks in block.c (which assume a single BlockBackend) to per-child callbacks gets us rid of the first few instances. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
* block: Decouple throttling from BlockDriverStateKevin Wolf2016-05-191-3/+0Star
| | | | | | | | | | | | | | | This moves the throttling related part of the BDS life cycle management to BlockBackend. The throttling group reference is now kept even when no medium is inserted. With this commit, throttling isn't disabled and then re-enabled any more during graph reconfiguration. This fixes the temporary breakage of I/O throttling when used with live snapshots or block jobs that manipulate the graph. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Drain throttling queue with BdrvChild callbackKevin Wolf2016-05-191-5/+11
| | | | | | | | | | | | | This removes the last part of I/O throttling from block/io.c and moves it to the BlockBackend. Instead of having knowledge about throttling inside io.c, we can call a BdrvChild callback .drained_begin/end, which happens to drain the throttled requests for BlockBackend parents. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Introduce BdrvChild.opaqueKevin Wolf2016-05-191-0/+1
| | | | | | | | | BlockBackends use it to get a back pointer from BdrvChild to BlockBackend in any BdrvChildRole callbacks. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Move I/O throttling configuration functions to BlockBackendKevin Wolf2016-05-191-2/+1Star
| | | | | | Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: Move throttling fields from BDS to BBKevin Wolf2016-05-191-13/+0Star
| | | | | | | | | | This patch changes where the throttling state is stored (used to be the BlockDriverState, now it is the BlockBackend), but it doesn't actually make it a BB level feature yet. For example, throttling is still disabled when the BDS is detached from the BB. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* block: throttle-groups: Use BlockBackend pointers internallyKevin Wolf2016-05-191-1/+0Star
| | | | | | | | | | | | | As a first step towards moving I/O throttling to the BlockBackend level, this patch changes all pointers in struct ThrottleGroup from referencing a BlockDriverState to referencing a BlockBackend. This change is valid because we made sure that throttling can only be enabled on BDSes which have a BB attached. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
* Add new block driver interface to add/delete a BDS's childWen Congyang2016-05-121-0/+5
| | | | | | | | | | | | | | In some cases, we want to take a quorum child offline, and take another child online. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 1462865799-19402-2-git-send-email-xiecl.fnst@cn.fujitsu.com Signed-off-by: Max Reitz <mreitz@redhat.com>