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2016-07-05block: Convert bdrv_co_do_readv/writev to BdrvChildKevin Wolf1-14/+15
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Convert bdrv_aio_writev() to BdrvChildKevin Wolf1-3/+3
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Convert bdrv_aio_readv() to BdrvChildKevin Wolf1-3/+3
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Convert bdrv_co_writev() to BdrvChildKevin Wolf1-3/+3
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Convert bdrv_co_readv() to BdrvChildKevin Wolf1-4/+4
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05block: Move request_alignment into BlockLimitEric Blake1-7/+7
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>
2016-07-05block: Split bdrv_merge_limits() from bdrv_refresh_limits()Eric Blake1-18/+13
During bdrv_merge_limits(), we were computing initial limits based on another BDS in two places. At first glance, the two computations are not identical (one is doing straight copying, the other is doing merging towards or away from zero) - but when you realize that the first round is starting with all-0 memory, all of the merging happens to work. Factoring out the merging makes it easier to track how two BDS limits are merged, in case we have future reasons to merge in even more limits. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Switch discard length bounds to byte-basedEric Blake1-7/+9
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>
2016-07-05block: Switch transfer length bounds to byte-basedEric Blake1-12/+11
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>
2016-07-05block: Set default request_alignment during bdrv_refresh_limits()Eric Blake1-0/+3
We want to eventually stick request_alignment alongside other BlockLimits, but first, we must ensure it is populated at the same time as all other limits, rather than being a special case that is set only when a block is first opened. Now that all drivers have been updated to supply an override of request_alignment during their .bdrv_refresh_limits(), as needed, the block layer itself can defer setting the default alignment until part of the overall bdrv_refresh_limits(). Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Fix harmless off-by-one in bdrv_aligned_preadv()Eric Blake1-1/+1
If the amount of data to read ends exactly on the total size of the bs, then we were wasting time creating a local qiov to read the data in preparation for what would normally be appending zeroes beyond the end, even though this corner case has nothing further to do. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Document supported flags during bdrv_aligned_preadv()Eric Blake1-1/+9
We don't pass any flags on to drivers to handle. Tighten an assert to explain why we pass 0 to bdrv_driver_preadv(), and add some comments on things to be aware of if we want to turn on per-BDS BDRV_REQ_FUA support during reads in the future. Also, document that we may want to consider using unmap during copy-on-read operations where the read is all zeroes. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-05block: Tighter assertions on bdrv_aligned_pwritev()Eric Blake1-5/+8
For symmetry with bdrv_aligned_preadv(), assert that the caller really has aligned things properly. This requires adding an align parameter, which is used now only in the new asserts, but will come in handy in a later patch that adds auto-fragmentation to the max transfer size, since that value need not always be a multiple of the alignment, and therefore must be rounded down. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-20block: process before_write_notifiers in bdrv_co_discardDenis V. Lunev1-0/+5
This is mandatory for correct backup creation. In the other case the content under this area would be lost. Dirty bits are set exactly like in bdrv_aligned_pwritev, i.e. they are set even if notifier has returned a error. Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1466093381-6120-4-git-send-email-den@openvz.org CC: Fam Zheng <famz@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-20block: fix race in bdrv_co_discard with drive-mirrorDenis V. Lunev1-1/+2
Actually we must set dirty bitmap dirty after we have written all our zeroes for correct processing in drive mirror code. In the other case we can face not zeroes in this area in mirror_iteration. Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1466093381-6120-3-git-send-email-den@openvz.org CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-20block: fixed BdrvTrackedRequest filling in bdrv_co_discardDenis V. Lunev1-2/+2
The request area is specified in bytes, not in sectors. Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1466093381-6120-2-git-send-email-den@openvz.org CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> CC: Max Reitz <mreitz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-16block: use the block job list in bdrv_drain_all()Alberto Garcia1-6/+18
bdrv_drain_all() pauses all block jobs by using bdrv_next() to iterate over all top-level BlockDriverStates. Therefore the code is unable to find block jobs in other nodes. This patch uses block_job_next() to iterate over all block jobs. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-id: 55ee7d7d4a65c28aa1a1b28823897ef326f328e2.1464346103.git.berto@igalia.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-16block: Remove bs->zero_beyond_eofKevin Wolf1-29/+23
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>
2016-06-16block: Make bdrv_load/save_vmstate coroutine_fnsKevin Wolf1-22/+58
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>
2016-06-16block: Allow .bdrv_load/save_vmstate() to return 0/-errnoKevin Wolf1-2/+15
The return value of .bdrv_load/save_vmstate() can be any non-negative number in case of success now. It used to be bytes/-errno. 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>
2016-06-16block: Make .bdrv_load_vmstate() vectoredKevin Wolf1-5/+20
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>
2016-06-16block: Introduce bdrv_preadv()Kevin Wolf1-7/+13
We already have a byte-based bdrv_pwritev(), but the read counterpart was still missing. This commit adds it. 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>
2016-06-16block: Don't enforce 512 byte minimum alignmentKevin Wolf1-5/+3
If block drivers say that they can do an alignment < 512 bytes, let's just suppose they mean it. raw-posix used to be an offender with respect to this, but it can actually deal with byte-aligned requests now. The default is still 512 bytes for any drivers that only implement sector-based interfaces, but it is 1 now for drivers that implement .bdrv_co_preadv. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-16block: Prepare bdrv_aligned_pwritev() for byte-aligned requestsKevin Wolf1-8/+5
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-16block: Prepare bdrv_aligned_preadv() for byte-aligned requestsKevin Wolf1-24/+20
This patch makes bdrv_aligned_preadv() ready to accept byte-aligned requests. Note that this doesn't mean that such requests are actually made. The caller still ensures that all requests are aligned to at least 512 bytes. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-16block: Byte-based bdrv_co_do_copy_on_readv()Kevin Wolf1-25/+38
In a first step to convert the common I/O path to work on bytes rather than sectors, this converts the copy-on-read logic that is used by bdrv_aligned_preadv(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-16block: Assert that flags are in rangeEric Blake1-0/+6
Add a new BDRV_REQ_MASK constant, and use it to make sure that caller flags are always valid. Tested with 'make check' and with qemu-iotests on both '-raw' and '-qcow2'; the only failure turned up was fixed in the previous commit. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08block: Don't emulate natively supported pwritev flagsKevin Wolf1-1/+3
Drivers that implement .bdrv_co_pwritev() get the flags passed as an argument to said function, but we also unconditionally emulate the flags anyway. We shouldn't do that. Fix this by clearing all flags that the driver supports natively after it returns from .bdrv_co_pwritev(). Fixes: 4df863f3 ('block: Make supported_write_flags a per-bds property') Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-06-08block: Kill bdrv_co_write_zeroes()Eric Blake1-13/+2
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>
2016-06-08block: Switch bdrv_write_zeroes() to byte interfaceEric Blake1-13/+21
Rename to bdrv_pwrite_zeroes() to let the compiler ensure we cater to the updated semantics. Do the same for bdrv_co_write_zeroes(). Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08block: Add .bdrv_co_pwrite_zeroes()Eric Blake1-35/+43
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>
2016-06-08block: Track write zero limits in bytesEric Blake1-9/+13
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>
2016-06-08block: split write_zeroes alwaysDenis V. Lunev1-13/+17
We should split requests even if they are less than write_zeroes_alignment. For example we can have the following request: offset 62k size 4k write_zeroes_alignment 64k The original code sent 1 request covering 2 qcow2 clusters, and resulted in both clusters being allocated. But by splitting the request, we can cater to the case where one of the two clusters can be zeroed as a whole, for only 1 cluster allocated after the operation. Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Eric Blake <eblake@redhat.com> CC: Kevin Wolf <kwolf@redhat.com> Message-Id: <1463476543-3087-2-git-send-email-den@openvz.org> [eblake: Avoid exceeding nb_sectors, hoist alignment checks out of loop, and update testsuite to show that patch works] Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-07block: Drop bdrv_ioctl_bh_cbFam Zheng1-18/+2
Similar to the "!drv || !drv->bdrv_aio_ioctl" case above, here it is okay to set co.ret and return. As pointed out by Paolo, a BH will be created as necessary by the caller (bdrv_co_maybe_schedule_bh). Besides, as pointed out by Kevin, "data" was leaked before. Reported-by: Kevin Wolf <kwolf@redhat.com> Reported-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20160601015223.19277-1-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-07block: Move BlockRequest type to io.cEric Blake1-0/+21
I was thrown by the fact that the public type BlockRequest had an anonymous union, but no obvious discriminator. Turns out that the only client of the second branch of the union was code internal to io.c, now that commit 91c6e4b killed public multiwrite, so move it into io.c and improve the comments. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1463699150-19445-1-git-send-email-eblake@redhat.com> Signed-off-by: Fam Zheng <famz@redhat.com>
2016-06-07block/io: optimize bdrv_co_pwritev for small requestsPeter Lieven1-0/+8
in a read-modify-write cycle a small request might cause head and tail to fall into the same aligned block. Currently QEMU reads the same block twice in this case which is not necessary. Signed-off-by: Peter Lieven <pl@kamp.de> Message-id: 1464607873-28206-1-git-send-email-pl@kamp.de Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-07block/io: Remove unused bdrv_aio_write_zeroes()Kevin Wolf1-11/+0
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-id: 1464599852-15392-1-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-25backup: Use BlockBackend for I/OKevin Wolf1-9/+0
This changes the backup block job to use the job's BlockBackend for performing its I/O. job->bs isn't used by the backup code any more afterwards. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25stream: Use BlockBackend for I/OKevin Wolf1-9/+0
This changes the streaming block job to use the job's BlockBackend for performing the COR reads. job->bs isn't used by the streaming code any more afterwards. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25block: Make bdrv_drain() use bdrv_drained_begin/end()Kevin Wolf1-36/+33
Until now, bdrv_drained_begin() used bdrv_drain() internally to drain the queue. This is kind of backwards and caused quiescing code to be duplicated because bdrv_drained_begin() had to ensure that no new requests come in even after bdrv_drain() returns, whereas bdrv_drain() had to have them because it could be called from other places. Instead move the bdrv_drain() code to bdrv_drained_begin() and make bdrv_drain() a simple wrapper around bdrv_drained_begin/end(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-25block: Fix bdrv_next() memory leakKevin Wolf1-6/+4
The bdrv_next() users all leaked the BdrvNextIterator after completing the iteration. Simply changing bdrv_next() to free the iterator before returning NULL at the end of list doesn't work because some callers exit the loop before looking at all BDSes. This patch moves the BdrvNextIterator from the heap to the stack of the caller and switches to a bdrv_first()/bdrv_next() interface for initialising the iterator. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-19block: Avoid bs->blk in bdrv_next()Kevin Wolf1-6/+7
We need to introduce a separate BdrvNextIterator struct that can keep more state than just the current BDS in order to avoid using the bs->blk pointer. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19block: Remove bdrv_aio_multiwrite()Kevin Wolf1-194/+0
Since virtio-blk implements request merging itself these days, the only remaining users are test cases for the function. That doesn't make the function exactly useful any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-05-19block: Don't check throttled reqs in bdrv_requests_pending()Kevin Wolf1-7/+0
Checking whether there are throttled requests requires going to the associated BlockBackend, which we want to avoid. All users of bdrv_requests_pending() in block/io.c already call bdrv_parent_drained_begin() first, which restarts all throttled requests, so no throttled requests can be left here and this is removal of dead code. The remaining users (assertions during graph manipulation in block.c) don't care about requests that are still queued in the BlockBackend and haven't been issued for a BlockDriverState yet. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block/io: Quiesce parents between drained_begin/endKevin Wolf1-0/+3
So far, bdrv_parent_drained_begin/end() was called for the duration of the actual bdrv_drain() at the beginning of a drained section, but we really should keep parents quiesced until the end of the drained section. This does not actually change behaviour at this point because the only user of the .drained_begin/end BdrvChildRole callback is I/O throttling, which already doesn't send any new requests after flushing its queue in .drained_begin. The patch merely removes a trap for future users. Reported-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Drain throttling queue with BdrvChild callbackKevin Wolf1-21/+18
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>
2016-05-19block: Move I/O throttling configuration functions to BlockBackendKevin Wolf1-41/+0
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Move actual I/O throttling to BlockBackendKevin Wolf1-10/+0
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-05-19block: Move throttling fields from BDS to BBKevin Wolf1-11/+25
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>
2016-05-19block: Convert throttle_group_get_name() to BlockBackendKevin Wolf1-1/+1
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>