summaryrefslogtreecommitdiffstats
path: root/block/io.c
Commit message (Collapse)AuthorAgeFilesLines
* block: add new BlockDriver handler: bdrv_cancel_in_flightVladimir Sementsov-Ogievskiy2021-02-121-0/+11
| | | | | | | | | It will be used to stop retrying NBD requests on mirror cancel. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20210205163720.887197-2-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: use int64_t bytes in copy_rangeVladimir Sementsov-Ogievskiy2021-02-031-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, convert now copy_range parameters which are already 64bit to signed type. It's safe as we don't work with requests overflowing BDRV_MAX_LENGTH (which is less than INT64_MAX), and do check the requests in bdrv_co_copy_range_internal() (by bdrv_check_request32(), which calls bdrv_check_request()). Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-17-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: support int64_t bytes in read/write wrappersVladimir Sementsov-Ogievskiy2021-02-031-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). Now, since bdrv_co_preadv_part() and bdrv_co_pwritev_part() have been updated, update all their wrappers. For all of them type of 'bytes' is widening, so callers are safe. We have update request_fn in blkverify.c simultaneously. Still it's just a pointer to one of bdrv_co_pwritev() or bdrv_co_preadv(), and type is widening for callers of the request_fn anyway. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-16-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> [eblake: grammar tweak] Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: support int64_t bytes in bdrv_co_p{read,write}v_part()Vladimir Sementsov-Ogievskiy2021-02-031-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, prepare bdrv_co_preadv_part() and bdrv_co_pwritev_part() and their remaining dependencies now. bdrv_pad_request() is updated simultaneously, as pointer to bytes passed to it both from bdrv_co_pwritev_part() and bdrv_co_preadv_part(). So, all callers of bdrv_pad_request() are updated to pass 64bit bytes. bdrv_pad_request() is already good for 64bit requests, add corresponding assertion. Look at bdrv_co_preadv_part() and bdrv_co_pwritev_part(). Type is widening, so callers are safe. Let's look inside the functions. In bdrv_co_preadv_part() and bdrv_aligned_pwritev() we only pass bytes to other already int64_t interfaces (and some obviously safe calculations), it's OK. In bdrv_co_do_zero_pwritev() aligned_bytes may become large now, still it's passed to bdrv_aligned_pwritev which supports int64_t bytes. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-15-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: support int64_t bytes in bdrv_aligned_preadv()Vladimir Sementsov-Ogievskiy2021-02-031-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, prepare bdrv_aligned_preadv() now. Make the bytes variable in bdrv_padding_rmw_read() int64_t, as it is only used for pass-through to bdrv_aligned_preadv(). All bdrv_aligned_preadv() callers are safe as type is widening. Let's look inside: - add a new-style assertion that request is good. - callees bdrv_is_allocated(), bdrv_co_do_copy_on_readv() supports int64_t bytes - conversion of bytes_remaining is OK, as we never have requests overflowing BDRV_MAX_LENGTH - looping through bytes_remaining is ok, num is updated to int64_t - for bdrv_driver_preadv we have same limit of max_transfer - qemu_iovec_memset is OK, as bytes+qiov_offset should not overflow qiov->size anyway (thanks to bdrv_check_qiov_request()) Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-14-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> [eblake: grammar tweak] Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: support int64_t bytes in bdrv_co_do_copy_on_readv()Vladimir Sementsov-Ogievskiy2021-02-031-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, prepare bdrv_co_do_copy_on_readv() now. 'bytes' type widening, so callers are safe. Look at the function itself: bytes, skip_bytes and progress become int64_t. bdrv_round_to_clusters() is OK, cluster_bytes now may be large. trace_bdrv_co_do_copy_on_readv() is OK looping through cluster_bytes is still OK. pnum is still capped to max_transfer, and to MAX_BOUNCE_BUFFER when we are going to do COR operation. Therefor calculations in qemu_iovec_from_buf() and bdrv_driver_preadv() should not change. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-13-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: support int64_t bytes in bdrv_aligned_pwritev()Vladimir Sementsov-Ogievskiy2021-02-031-8/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, prepare bdrv_aligned_pwritev() now and convert the dependencies: bdrv_co_write_req_prepare() and bdrv_co_write_req_finish() to signed type bytes. Conversion of bdrv_co_write_req_prepare() and bdrv_co_write_req_finish() is definitely safe, as all requests in block/io must not overflow BDRV_MAX_LENGTH. Still add assertions. For bdrv_aligned_pwritev() 'bytes' type is widened, so callers are safe. Let's check usage of the parameter inside the function. Passing to bdrv_co_write_req_prepare() and bdrv_co_write_req_finish() is OK. Passing to qemu_iovec_* is OK after new assertion. All other callees are already updated to int64_t. Checking alignment is not changed, offset + bytes and qiov_offset + bytes calculations are safe (thanks to new assertions). max_transfer is kept to be int for now. It has a default of INT_MAX here, and some drivers may rely on it. It's to be refactored later. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-12-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: support int64_t bytes in bdrv_co_do_pwrite_zeroes()Vladimir Sementsov-Ogievskiy2021-02-031-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, prepare bdrv_co_do_pwrite_zeroes() now. Callers are safe, as converting int to int64_t is safe. Concentrate on 'bytes' usage in the function (thx to Eric Blake): compute 'int tail' via % 'int alignment' - safe fragmentation loop 'int num' - still fragments with a cap on max_transfer use of 'num' within the loop MIN(bytes, max_transfer) as well as %alignment - still works, so calculations in if (head) {} are safe clamp size by 'int max_write_zeroes' - safe drv->bdrv_co_pwrite_zeroes(int) - safe because of clamping clamp size by 'int max_transfer' - safe buf allocation is still clamped to max_transfer qemu_iovec_init_buf(size_t) - safe because of clamping bdrv_driver_pwritev(uint64_t) - safe Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-11-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: use int64_t bytes in driver wrappersVladimir Sementsov-Ogievskiy2021-02-031-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). So, convert driver wrappers parameters which are already 64bit to signed type. Requests in block/io.c must never exceed BDRV_MAX_LENGTH (which is less than INT64_MAX), which makes the conversion to signed 64bit type safe. Add corresponding assertions. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-10-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block: use int64_t as bytes type in tracked requestsEric Blake2021-02-031-5/+9
| | | | | | | | | | | | | | | | | | | | | We are generally moving to int64_t for both offset and bytes parameters on all io paths. Main motivation is realization of 64-bit write_zeroes operation for fast zeroing large disk chunks, up to the whole disk. We chose signed type, to be consistent with off_t (which is signed) and with possibility for signed return type (where negative value means error). All requests in block/io must not overflow BDRV_MAX_LENGTH, all external users of BdrvTrackedRequest already have corresponding assertions, so we are safe. Add some assertions still. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-9-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: improve bdrv_check_request: check qiov tooVladimir Sementsov-Ogievskiy2021-02-031-7/+39
| | | | | | | | | Operations with qiov add more restrictions on bytes, let's cover it. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-8-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: bdrv_pad_request(): support qemu_iovec_init_extended failureVladimir Sementsov-Ogievskiy2021-02-031-14/+31
| | | | | | | | | | | | Make bdrv_pad_request() honest: return error if qemu_iovec_init_extended() failed. Update also bdrv_padding_destroy() to clean the structure for safety. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-6-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block/io: refactor bdrv_pad_request(): move bdrv_pad_request() upVladimir Sementsov-Ogievskiy2021-02-031-6/+19
| | | | | | | | | | | Prepare for the following patch when bdrv_pad_request() will be able to fail. Update the comments. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-5-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> [eblake: grammar tweak] Signed-off-by: Eric Blake <eblake@redhat.com>
* block: fix theoretical overflow in bdrv_init_padding()Vladimir Sementsov-Ogievskiy2021-02-031-2/+6
| | | | | | | | | | | | | Calculation of sum may theoretically overflow, so use 64bit type and add some good assertions. Use int64_t constantly. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-4-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> [eblake: tweak assertion order] Signed-off-by: Eric Blake <eblake@redhat.com>
* util/iov: make qemu_iovec_init_extended() honestVladimir Sementsov-Ogievskiy2021-02-031-3/+7
| | | | | | | | | | | | | | | | Actually, we can't extend the io vector in all cases. Handle possible MAX_IOV and size_t overflows. For now add assertion to callers (actually they rely on success anyway) and fix them in the following patch. Add also some additional good assertions to qemu_iovec_init_slice() while being here. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-3-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
* block: refactor bdrv_check_request: add errpVladimir Sementsov-Ogievskiy2021-02-031-7/+22
| | | | | | | | | | | It's better to pass &error_abort than just assert that result is 0: on crash, we'll immediately see the reason in the backtrace. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201211183934.169161-2-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> [eblake: fix iotest 206 fallout] Signed-off-by: Eric Blake <eblake@redhat.com>
* block: include supported_read_flags into BDS structureAndrey Shinkevich2021-01-261-2/+8
| | | | | | | | | | | | | | | Add the new member supported_read_flags to the BlockDriverState structure. It will control the flags set for copy-on-read operations. Make the block generic layer evaluate supported read flags before they go to a block driver. Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> [vsementsov: use assert instead of abort] Reviewed-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201216061703.70908-8-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: introduce BDRV_REQ_NO_WAIT flagVladimir Sementsov-Ogievskiy2020-12-181-1/+10
| | | | | | | | | | | Add flag to make serialising request no wait: if there are conflicting requests, just return error immediately. It's will be used in upcoming preallocate filter. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201021145859.11201-7-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: bdrv_mark_request_serialising: split non-waiting functionVladimir Sementsov-Ogievskiy2020-12-181-12/+23
| | | | | | | | | | | | | | | | | | We'll need a separate function, which will only "mark" request serialising with specified align but not wait for conflicting requests. So, it will be like old bdrv_mark_request_serialising(), before merging bdrv_wait_serialising_requests_locked() into it. To reduce the possible mess, let's do the following: Public function that does both marking and waiting will be called bdrv_make_request_serialising, and private function which will only "mark" will be called tracked_request_set_serialising(). Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-Id: <20201021145859.11201-6-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block/io: bdrv_wait_serialising_requests_locked: drop extra bs argVladimir Sementsov-Ogievskiy2020-12-181-5/+5
| | | | | | | | | | | | | bs is linked in req, so no needs to pass it separately. Most of tracked-requests API doesn't have bs argument. Actually, after this patch only tracked_request_begin has it, but it's for purpose. While being here, also add a comment about what "_locked" is. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201021145859.11201-5-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block/io: split out bdrv_find_conflicting_requestVladimir Sementsov-Ogievskiy2020-12-181-30/+41
| | | | | | | | | To be reused in separate. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20201021145859.11201-4-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block/io.c: drop assertion on double waiting for request serialisationVladimir Sementsov-Ogievskiy2020-12-181-10/+1Star
| | | | | | | | | | | | | | | | | The comments states, that on misaligned request we should have already been waiting. But for bdrv_padding_rmw_read, we called bdrv_mark_request_serialising with align = request_alignment, and now we serialise with align = cluster_size. So we may have to wait again with larger alignment. Note, that the only user of BDRV_REQ_SERIALISING is backup which issues cluster-aligned requests, so seems the assertion should not fire for now. But it's wrong anyway. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20201021145859.11201-3-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: Fix deadlock in bdrv_co_yield_to_drain()Kevin Wolf2020-12-111-17/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | If bdrv_co_yield_to_drain() is called for draining a block node that runs in a different AioContext, it keeps that AioContext locked while it yields and schedules a BH in the AioContext to do the actual drain. As long as executing the BH is the very next thing that the event loop of the node's AioContext does, this actually happens to work, but when it tries to execute something else that wants to take the AioContext lock, it will deadlock. (In the bug report, this other thing is a virtio-scsi device running virtio_scsi_data_plane_handle_cmd().) Instead, always drop the AioContext lock across the yield and reacquire it only when the coroutine is reentered. The BH needs to unconditionally take the lock for itself now. This fixes the 'block_resize' QMP command on a block node that runs in an iothread. Cc: qemu-stable@nongnu.org Fixes: eb94b81a94bce112e6b206df846c1551aaf6cab6 Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1903511 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20201203172311.68232-4-kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: introduce BDRV_MAX_LENGTHVladimir Sementsov-Ogievskiy2020-12-111-9/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We are going to modify block layer to work with 64bit requests. And first step is moving to int64_t type for both offset and bytes arguments in all block request related functions. It's mostly safe (when widening signed or unsigned int to int64_t), but switching from uint64_t is questionable. So, let's first establish the set of requests we want to work with. First signed int64_t should be enough, as off_t is signed anyway. Then, obviously offset + bytes should not overflow. And most interesting: (offset + bytes) being aligned up should not overflow as well. Aligned to what alignment? First thing that comes in mind is bs->bl.request_alignment, as we align up request to this alignment. But there is another thing: look at bdrv_mark_request_serialising(). It aligns request up to some given alignment. And this parameter may be bdrv_get_cluster_size(), which is often a lot greater than bs->bl.request_alignment. Note also, that bdrv_mark_request_serialising() uses signed int64_t for calculations. So, actually, we already depend on some restrictions. Happily, bdrv_get_cluster_size() returns int and bs->bl.request_alignment has 32bit unsigned type, but defined to be a power of 2 less than INT_MAX. So, we may establish, that INT_MAX is absolute maximum for any kind of alignment that may occur with the request. Note, that bdrv_get_cluster_size() is not documented to return power of 2, still bdrv_mark_request_serialising() behaves like it is. Also, backup uses bdi.cluster_size and is not prepared to it not being power of 2. So, let's establish that Qemu supports only power-of-2 clusters and alignments. So, alignment can't be greater than 2^30. Finally to be safe with calculations, to not calculate different maximums for different nodes (depending on cluster size and request_alignment), let's simply set QEMU_ALIGN_DOWN(INT64_MAX, 2^30) as absolute maximum bytes length for Qemu. Actually, it's not much less than INT64_MAX. OK, then, let's apply it to block/io. Let's consider all block/io entry points of offset/bytes: 4 bytes/offset interface functions: bdrv_co_preadv_part(), bdrv_co_pwritev_part(), bdrv_co_copy_range_internal() and bdrv_co_pdiscard() and we check them all with bdrv_check_request(). We also have one entry point with only offset: bdrv_co_truncate(). Check the offset. And one public structure: BdrvTrackedRequest. Happily, it has only three external users: file-posix.c: adopted by this patch write-threshold.c: only read fields test-write-threshold.c: sets obviously small constant values Better is to make the structure private and add corresponding interfaces.. Still it's not obvious what kind of interface is needed for file-posix.c. Let's keep it public but add corresponding assertions. After this patch we'll convert functions in block/io.c to int64_t bytes and offset parameters. We can assume that offset/bytes pair always satisfy new restrictions, and make corresponding assertions where needed. If we reach some offset/bytes point in block/io.c missing bdrv_check_request() it is considered a bug. As well, if block/io.c modifies a offset/bytes request, expanding it more then aligning up to request_alignment, it's a bug too. For all io requests except for discard we keep for now old restriction of 32bit request length. iotest 206 output error message changed, as now test disk size is larger than new limit. Add one more test case with new maximum disk size to cover too-big-L1 case. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201203222713.13507-5-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/io: bdrv_check_byte_request(): drop bdrv_is_inserted()Vladimir Sementsov-Ogievskiy2020-12-111-13/+12Star
| | | | | | | | | | | | | | | | | | | | | | | | | Move bdrv_is_inserted() calls into callers. We are going to make bdrv_check_byte_request() a clean thing. bdrv_is_inserted() is not about checking the request, it's about checking the bs. So, it should be separate. With this patch we probably change error path for some failure scenarios. But depending on the fact that querying too big request on empty cdrom (or corrupted qcow2 node with no drv) will result in EIO and not ENOMEDIUM would be very strange. More over, we are going to move to 64bit requests, so larger requests will be allowed anyway. More over, keeping in mind that cdrom is the only driver that has .bdrv_is_inserted() handler it's strange that we should care so much about it in generic block layer, intuitively we should just do read and write, and cdrom driver should return correct errors if it is not inserted. But it's a work for another series. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201203222713.13507-4-vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/io: bdrv_refresh_limits(): use ERRP_GUARDVladimir Sementsov-Ogievskiy2020-12-111-4/+3Star
| | | | | | | | | This simplifies following commit. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20201203222713.13507-3-vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block: Return depth level during bdrv_is_allocated_aboveEric Blake2020-10-301-8/+23
| | | | | | | | | | | | | | When checking for allocation across a chain, it's already easy to count the depth within the chain at which the allocation is found. Instead of throwing that information away, return it to the caller. Existing callers only cared about allocated/non-allocated, but having a depth available will be used by NBD in the next patch. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20201027050556.269064-9-eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
* block: End quiescent sections when a BDS is deletedGreg Kurz2020-10-271-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a BDS gets deleted during blk_drain_all(), it might miss a call to bdrv_do_drained_end(). This means missing a call to aio_enable_external() and the AIO context remains disabled for ever. This can cause a device to become irresponsive and to disrupt the guest execution, ie. hang, loop forever or worse. This scenario is quite easy to encounter with virtio-scsi on POWER when punching multiple blockdev-create QMP commands while the guest is booting and it is still running the SLOF firmware. This happens because SLOF disables/re-enables PCI devices multiple times via IO/MEM/MASTER bits of PCI_COMMAND register after the initial probe/feature negotiation, as it tends to work with a single device at a time at various stages like probing and running block/network bootloaders without doing a full reset in-between. This naturally generates many dataplane stops and starts, and thus many drain sections that can race with blockdev_create_run(). In the end, SLOF bails out. It is somehow reproducible on x86 but it requires to generate articial dataplane start/stop activity with stop/cont QMP commands. In this case, seabios ends up looping for ever, waiting for the virtio-scsi device to send a response to a command it never received. Add a helper that pairs all previously called bdrv_do_drained_begin() with a bdrv_do_drained_end() and call it from bdrv_close(). While at it, update the "/bdrv-drain/graph-change/drain_all" test in test-bdrv-drain so that it can catch the issue. BugId: https://bugzilla.redhat.com/show_bug.cgi?id=1874441 Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <160346526998.272601.9045392804399803158.stgit@bahia.lan> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Skip copy-on-write when allocating a zero clusterAlberto Garcia2020-10-271-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit c8bb23cbdbe32f5c326365e0a82e1b0e68cdcd8a when a write request results in a new allocation QEMU first tries to see if the rest of the cluster outside the written area contains only zeroes. In that case, instead of doing a normal copy-on-write operation and writing explicit zero buffers to disk, the code zeroes the whole cluster efficiently using pwrite_zeroes() with BDRV_REQ_NO_FALLBACK. This improves performance very significantly but it only happens when we are writing to an area that was completely unallocated before. Zero clusters (QCOW2_CLUSTER_ZERO_*) are treated like normal clusters and are therefore slower to allocate. This happens because the code uses bdrv_is_allocated_above() rather bdrv_block_status_above(). The former is not as accurate for this purpose but it is faster. However in the case of qcow2 the underlying call does already report zero clusters just fine so there is no reason why we cannot use that information. After testing 4KB writes on an image that only contains zero clusters this patch results in almost five times more IOPS. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <6d77cab968c501c44d6e1089b9bc91b04170b49e.1603731354.git.berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* qcow2: Report BDRV_BLOCK_ZERO more accurately in bdrv_co_block_status()Alberto Garcia2020-10-271-4/+4
| | | | | | | | | | | | | | | If a BlockDriverState supports backing files but has none then any unallocated area reads back as zeroes. bdrv_co_block_status() is only reporting this is if want_zero is true, but this is an inexpensive test and there is no reason not to do it in all cases. Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <66fa0914a0e2b727ab6d1b63ca773d7cd29a9a9e.1603731354.git.berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
* block/io: fix bdrv_is_allocated_aboveVladimir Sementsov-Ogievskiy2020-10-231-38/+5Star
| | | | | | | | | | | | | | | | | | bdrv_is_allocated_above wrongly handles short backing files: it reports after-EOF space as UNALLOCATED which is wrong, as on read the data is generated on the level of short backing file (if all overlays have unallocated areas at that place). Reusing bdrv_common_block_status_above fixes the issue and unifies code path. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20200924194003.22080-5-vsementsov@virtuozzo.com [Fix s/has/have/ as suggested by Eric Blake. Fix s/area/areas/. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/io: bdrv_common_block_status_above: support bs == baseVladimir Sementsov-Ogievskiy2020-10-231-1/+5
| | | | | | | | | | | | | | | We are going to reuse bdrv_common_block_status_above in bdrv_is_allocated_above. bdrv_is_allocated_above may be called with include_base == false and still bs == base (for ex. from img_rebase()). So, support this corner case. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20200924194003.22080-4-vsementsov@virtuozzo.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/io: bdrv_common_block_status_above: support include_baseVladimir Sementsov-Ogievskiy2020-10-231-7/+14
| | | | | | | | | | | In order to reuse bdrv_common_block_status_above in bdrv_is_allocated_above, let's support include_base parameter. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20200924194003.22080-3-vsementsov@virtuozzo.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/io: fix bdrv_co_block_status_aboveVladimir Sementsov-Ogievskiy2020-10-231-14/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bdrv_co_block_status_above has several design problems with handling short backing files: 1. With want_zeros=true, it may return ret with BDRV_BLOCK_ZERO but without BDRV_BLOCK_ALLOCATED flag, when actually short backing file which produces these after-EOF zeros is inside requested backing sequence. 2. With want_zero=false, it may return pnum=0 prior to actual EOF, because of EOF of short backing file. Fix these things, making logic about short backing files clearer. With fixed bdrv_block_status_above we also have to improve is_zero in qcow2 code, otherwise iotest 154 will fail, because with this patch we stop to merge zeros of different types (produced by fully unallocated in the whole backing chain regions vs produced by short backing files). Note also, that this patch leaves for another day the general problem around block-status: misuse of BDRV_BLOCK_ALLOCATED as is-fs-allocated vs go-to-backing. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20200924194003.22080-2-vsementsov@virtuozzo.com [Fix s/comes/come/ as suggested by Eric Blake --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* block/io: refactor save/load vmstateVladimir Sementsov-Ogievskiy2020-10-051-33/+35
| | | | | | | | | | | Like for read/write in a previous commit, drop extra indirection layer, generate directly bdrv_readv_vmstate() and bdrv_writev_vmstate(). Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200924185414.28642-8-vsementsov@virtuozzo.com>
* block: drop bdrv_prwvVladimir Sementsov-Ogievskiy2020-10-051-40/+9Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we are not maintaining boilerplate code for coroutine wrappers, there is no more sense in keeping the extra indirection layer of bdrv_prwv(). Let's drop it and instead generate pure bdrv_preadv() and bdrv_pwritev(). Currently, bdrv_pwritev() and bdrv_preadv() are returning bytes on success, auto generated functions will instead return zero, as their _co_ prototype. Still, it's simple to make the conversion safe: the only external user of bdrv_pwritev() is test-bdrv-drain, and it is comfortable enough with bdrv_co_pwritev() instead. So prototypes are moved to local block/coroutines.h. Next, the only internal use is bdrv_pread() and bdrv_pwrite(), which are modified to return bytes on success. Of course, it would be great to convert bdrv_pread() and bdrv_pwrite() to return 0 on success. But this requires audit (and probably conversion) of all their users, let's leave it for another day refactoring. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200924185414.28642-7-vsementsov@virtuozzo.com>
* block: generate coroutine-wrapper codeVladimir Sementsov-Ogievskiy2020-10-051-212/+0Star
| | | | | | | | | | | Use code generation implemented in previous commit to generated coroutine wrappers in block.c and block/io.c Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200924185414.28642-6-vsementsov@virtuozzo.com>
* block: declare some coroutine functions in block/coroutines.hVladimir Sementsov-Ogievskiy2020-10-051-17/+17
| | | | | | | | | | | | | | | | We are going to keep coroutine-wrappers code (structure-packing parameters, BDRV_POLL wrapper functions) in separate auto-generated files. So, we'll need a header with declaration of original _co_ functions, for those which are static now. As well, we'll need declarations for wrapper functions. Do these declarations now, as a preparation step. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200924185414.28642-4-vsementsov@virtuozzo.com>
* block/io: refactor coroutine wrappersVladimir Sementsov-Ogievskiy2020-10-051-28/+32
| | | | | | | | | | | | | | | | | | | | | | | Most of our coroutine wrappers already follow this convention: We have 'coroutine_fn bdrv_co_<something>(<normal argument list>)' as the core function, and a wrapper 'bdrv_<something>(<same argument list>)' which does parameter packing and calls bdrv_run_co(). The only outsiders are the bdrv_prwv_co and bdrv_common_block_status_above wrappers. Let's refactor them to behave as the others, it simplifies further conversion of coroutine wrappers. This patch adds an indirection layer, but it will be compensated by a further commit, which will drop bdrv_co_prwv together with the is_write logic, to keep the read and write paths separate. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200924185414.28642-3-vsementsov@virtuozzo.com>
* qemu/atomic.h: rename atomic_ to qatomic_Stefan Hajnoczi2020-09-231-24/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clang's C11 atomic_fetch_*() functions only take a C11 atomic type pointer argument. QEMU uses direct types (int, etc) and this causes a compiler error when a QEMU code calls these functions in a source file that also included <stdatomic.h> via a system header file: $ CC=clang CXX=clang++ ./configure ... && make ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid) Avoid using atomic_*() names in QEMU's atomic.h since that namespace is used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h and <stdatomic.h> can co-exist. I checked /usr/include on my machine and searched GitHub for existing "qatomic_" users but there seem to be none. This patch was generated using: $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \ sort -u >/tmp/changed_identifiers $ for identifier in $(</tmp/changed_identifiers); do sed -i "s%\<$identifier\>%q$identifier%g" \ $(git grep -I -l "\<$identifier\>") done I manually fixed line-wrap issues and misaligned rST tables. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
* block: Inline bdrv_co_block_status_from_*()Max Reitz2020-09-071-34/+17Star
| | | | | | | | | | | | | | With bdrv_filter_bs(), we can easily handle this default filter behavior in bdrv_co_block_status(). blkdebug wants to have an additional assertion, so it keeps its own implementation, except bdrv_co_block_status_from_file() needs to be inlined there. Suggested-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
* block: Use CAF in bdrv_co_rw_vmstate()Max Reitz2020-09-071-2/+3
| | | | | | | | | | | | If a node whose driver does not provide VM state functions has a metadata child, the VM state should probably go there; if it is a filter, the VM state should probably go there. It follows that we should generally go down to the primary child. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
* block: Iterate over children in refresh_limitsMax Reitz2020-09-071-16/+16
| | | | | | | | Instead of looking at just bs->file and bs->backing, we should look at all children that could end up receiving forwarded requests. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
* block: Flush all children in generic codeMax Reitz2020-09-071-6/+17
| | | | | | | | | | | | | | | | | | If the driver does not support .bdrv_co_flush() so bdrv_co_flush() itself has to flush the children of the given node, it should not flush just bs->file->bs, but in fact all children that might have been written to (judging from the permissions taken on them). This is a bug fix for qcow2 images with an external data file, as they so far did not flush that data_file node. In any case, the BLKDBG_EVENT() should be emitted on the primary child, because that is where a blkdebug node would be if there is any. Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
* block: Use bdrv_cow_child() in bdrv_co_truncate()Max Reitz2020-09-071-3/+4
| | | | | | | | | The condition modified here is not about potentially filtered children, but only about COW sources (i.e. traditional backing files). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
* block: Use CAFs in block status functionsMax Reitz2020-09-071-9/+10
| | | | | | | Use the child access functions in the block status inquiry functions as appropriate. Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: Use bdrv_filter_(bs|child) where obviousMax Reitz2020-09-071-2/+5
| | | | | | | | | | | | | | | | | | | | | Places that use patterns like if (bs->drv->is_filter && bs->file) { ... something about bs->file->bs ... } should be BlockDriverState *filtered = bdrv_filter_bs(bs); if (filtered) { ... something about @filtered ... } instead. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
* block: Fix bdrv_aligned_p*v() for qiov_offset != 0Max Reitz2020-07-281-4/+6
| | | | | | | | | | | | | | | | | | | Since these functions take a @qiov_offset, they must always take it into account when working with @qiov. There are a couple of places where they do not, but they should. Fixes: 65cd4424b9df03bb5195351c33e04cbbecc0705c ("block/io: bdrv_aligned_preadv: use and support qiov_offset") Fixes: 28c4da28695bdbe04b336b2c9c463876cc3aaa6d ("block/io: bdrv_aligned_pwritev: use and support qiov_offset") Reported-by: Claudio Fontana <cfontana@suse.de> Reported-by: Bruce Rogers <brogers@suse.com> Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200728120806.265916-2-mreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Tested-by: Claudio Fontana <cfontana@suse.de> Tested-by: Bruce Rogers <brogers@suse.com>
* block: drop unallocated_blocks_are_zeroVladimir Sementsov-Ogievskiy2020-07-061-7/+2Star
| | | | | | | | | | | | | | | Currently this field only set by qed and qcow2. But in fact, all backing-supporting formats (parallels, qcow, qcow2, qed, vmdk) share these semantics: on unallocated blocks, if there is no backing file they just memset the buffer with zeroes. So, document this behavior for .supports_backing and drop .unallocated_blocks_are_zero Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200528094405.145708-10-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
* block: inline bdrv_unallocated_blocks_are_zero()Vladimir Sementsov-Ogievskiy2020-07-061-3/+8
| | | | | | | | | | | The function has only one user: bdrv_co_block_status(). Inline it to simplify reviewing of the following patches, which will finally drop unallocated_blocks_are_zero field too. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200528094405.145708-3-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz <mreitz@redhat.com>