diff --git a/block.c b/block.c index a307c151a8..0af890f647 100644 --- a/block.c +++ b/block.c @@ -6480,6 +6480,13 @@ int coroutine_fn bdrv_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) } memset(bdi, 0, sizeof(*bdi)); ret = drv->bdrv_co_get_info(bs, bdi); + if (bdi->subcluster_size == 0) { + /* + * If the driver left this unset, subclusters are not supported. + * Then it is safe to treat each cluster as having only one subcluster. + */ + bdi->subcluster_size = bdi->cluster_size; + } if (ret < 0) { return ret; } diff --git a/block/io.c b/block/io.c index 055fcf7438..76e7df18d8 100644 --- a/block/io.c +++ b/block/io.c @@ -728,21 +728,21 @@ BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs) } /** - * Round a region to cluster boundaries + * Round a region to subcluster (if supported) or cluster boundaries */ void coroutine_fn GRAPH_RDLOCK -bdrv_round_to_clusters(BlockDriverState *bs, int64_t offset, int64_t bytes, - int64_t *cluster_offset, int64_t *cluster_bytes) +bdrv_round_to_subclusters(BlockDriverState *bs, int64_t offset, int64_t bytes, + int64_t *align_offset, int64_t *align_bytes) { BlockDriverInfo bdi; IO_CODE(); - if (bdrv_co_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) { - *cluster_offset = offset; - *cluster_bytes = bytes; + if (bdrv_co_get_info(bs, &bdi) < 0 || bdi.subcluster_size == 0) { + *align_offset = offset; + *align_bytes = bytes; } else { - int64_t c = bdi.cluster_size; - *cluster_offset = QEMU_ALIGN_DOWN(offset, c); - *cluster_bytes = QEMU_ALIGN_UP(offset - *cluster_offset + bytes, c); + int64_t c = bdi.subcluster_size; + *align_offset = QEMU_ALIGN_DOWN(offset, c); + *align_bytes = QEMU_ALIGN_UP(offset - *align_offset + bytes, c); } } @@ -1168,8 +1168,8 @@ bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, int64_t bytes, void *bounce_buffer = NULL; BlockDriver *drv = bs->drv; - int64_t cluster_offset; - int64_t cluster_bytes; + int64_t align_offset; + int64_t align_bytes; int64_t skip_bytes; int ret; int max_transfer = MIN_NON_ZERO(bs->bl.max_transfer, @@ -1203,28 +1203,28 @@ bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, int64_t bytes, * BDRV_REQUEST_MAX_BYTES (even when the original read did not), which * is one reason we loop rather than doing it all at once. */ - bdrv_round_to_clusters(bs, offset, bytes, &cluster_offset, &cluster_bytes); - skip_bytes = offset - cluster_offset; + bdrv_round_to_subclusters(bs, offset, bytes, &align_offset, &align_bytes); + skip_bytes = offset - align_offset; trace_bdrv_co_do_copy_on_readv(bs, offset, bytes, - cluster_offset, cluster_bytes); + align_offset, align_bytes); - while (cluster_bytes) { + while (align_bytes) { int64_t pnum; if (skip_write) { ret = 1; /* "already allocated", so nothing will be copied */ - pnum = MIN(cluster_bytes, max_transfer); + pnum = MIN(align_bytes, max_transfer); } else { - ret = bdrv_is_allocated(bs, cluster_offset, - MIN(cluster_bytes, max_transfer), &pnum); + ret = bdrv_is_allocated(bs, align_offset, + MIN(align_bytes, max_transfer), &pnum); if (ret < 0) { /* * Safe to treat errors in querying allocation as if * unallocated; we'll probably fail again soon on the * read, but at least that will set a decent errno. */ - pnum = MIN(cluster_bytes, max_transfer); + pnum = MIN(align_bytes, max_transfer); } /* Stop at EOF if the image ends in the middle of the cluster */ @@ -1242,7 +1242,7 @@ bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, int64_t bytes, /* Must copy-on-read; use the bounce buffer */ pnum = MIN(pnum, MAX_BOUNCE_BUFFER); if (!bounce_buffer) { - int64_t max_we_need = MAX(pnum, cluster_bytes - pnum); + int64_t max_we_need = MAX(pnum, align_bytes - pnum); int64_t max_allowed = MIN(max_transfer, MAX_BOUNCE_BUFFER); int64_t bounce_buffer_len = MIN(max_we_need, max_allowed); @@ -1254,7 +1254,7 @@ bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, int64_t bytes, } qemu_iovec_init_buf(&local_qiov, bounce_buffer, pnum); - ret = bdrv_driver_preadv(bs, cluster_offset, pnum, + ret = bdrv_driver_preadv(bs, align_offset, pnum, &local_qiov, 0, 0); if (ret < 0) { goto err; @@ -1266,13 +1266,13 @@ bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, int64_t bytes, /* FIXME: Should we (perhaps conditionally) be setting * BDRV_REQ_MAY_UNMAP, if it will allow for a sparser copy * that still correctly reads as zero? */ - ret = bdrv_co_do_pwrite_zeroes(bs, cluster_offset, pnum, + ret = bdrv_co_do_pwrite_zeroes(bs, align_offset, pnum, BDRV_REQ_WRITE_UNCHANGED); } else { /* This does not change the data on the disk, it is not * necessary to flush even in cache=writethrough mode. */ - ret = bdrv_driver_pwritev(bs, cluster_offset, pnum, + ret = bdrv_driver_pwritev(bs, align_offset, pnum, &local_qiov, 0, BDRV_REQ_WRITE_UNCHANGED); } @@ -1301,8 +1301,8 @@ bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, int64_t bytes, } } - cluster_offset += pnum; - cluster_bytes -= pnum; + align_offset += pnum; + align_bytes -= pnum; progress += pnum - skip_bytes; skip_bytes = 0; } diff --git a/block/mirror.c b/block/mirror.c index d3cacd1708..e213a892db 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -283,8 +283,8 @@ static int coroutine_fn mirror_cow_align(MirrorBlockJob *s, int64_t *offset, need_cow |= !test_bit((*offset + *bytes - 1) / s->granularity, s->cow_bitmap); if (need_cow) { - bdrv_round_to_clusters(blk_bs(s->target), *offset, *bytes, - &align_offset, &align_bytes); + bdrv_round_to_subclusters(blk_bs(s->target), *offset, *bytes, + &align_offset, &align_bytes); } if (align_bytes > max_bytes) { @@ -576,8 +576,8 @@ static void coroutine_fn mirror_iteration(MirrorBlockJob *s) int64_t target_offset; int64_t target_bytes; WITH_GRAPH_RDLOCK_GUARD() { - bdrv_round_to_clusters(blk_bs(s->target), offset, io_bytes, - &target_offset, &target_bytes); + bdrv_round_to_subclusters(blk_bs(s->target), offset, io_bytes, + &target_offset, &target_bytes); } if (target_offset == offset && target_bytes == io_bytes) { diff --git a/block/qcow2.c b/block/qcow2.c index c51388e99d..b48cd9ce63 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -5197,6 +5197,7 @@ qcow2_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) { BDRVQcow2State *s = bs->opaque; bdi->cluster_size = s->cluster_size; + bdi->subcluster_size = s->subcluster_size; bdi->vm_state_offset = qcow2_vm_state_offset(s); bdi->is_dirty = s->incompatible_features & QCOW2_INCOMPAT_DIRTY; return 0; diff --git a/include/block/block-common.h b/include/block/block-common.h index e15395f2cb..df5ffc8d09 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -132,6 +132,11 @@ typedef struct BlockZoneWps { typedef struct BlockDriverInfo { /* in bytes, 0 if irrelevant */ int cluster_size; + /* + * A fraction of cluster_size, if supported (currently QCOW2 only); if + * disabled or unsupported, set equal to cluster_size. + */ + int subcluster_size; /* offset at which the VM state can be saved (0 if not possible) */ int64_t vm_state_offset; bool is_dirty; diff --git a/include/block/block-io.h b/include/block/block-io.h index 4415506e40..6db48f2d35 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -189,10 +189,10 @@ bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, Error **errp); BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs); -void bdrv_round_to_clusters(BlockDriverState *bs, - int64_t offset, int64_t bytes, - int64_t *cluster_offset, - int64_t *cluster_bytes); +void bdrv_round_to_subclusters(BlockDriverState *bs, + int64_t offset, int64_t bytes, + int64_t *cluster_offset, + int64_t *cluster_bytes); void bdrv_get_backing_filename(BlockDriverState *bs, char *filename, int filename_size); diff --git a/migration/block.c b/migration/block.c index b9580a6c7e..86c2256a2b 100644 --- a/migration/block.c +++ b/migration/block.c @@ -368,7 +368,9 @@ static void unset_dirty_tracking(void) BlkMigDevState *bmds; QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { - bdrv_release_dirty_bitmap(bmds->dirty_bitmap); + if (bmds->dirty_bitmap) { + bdrv_release_dirty_bitmap(bmds->dirty_bitmap); + } } } @@ -676,13 +678,18 @@ static int64_t get_remaining_dirty(void) static void block_migration_cleanup_bmds(void) { BlkMigDevState *bmds; + BlockDriverState *bs; AioContext *ctx; unset_dirty_tracking(); while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) { QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry); - bdrv_op_unblock_all(blk_bs(bmds->blk), bmds->blocker); + + bs = blk_bs(bmds->blk); + if (bs) { + bdrv_op_unblock_all(bs, bmds->blocker); + } error_free(bmds->blocker); /* Save ctx, because bmds->blk can disappear during blk_unref. */ diff --git a/tests/qemu-iotests/197 b/tests/qemu-iotests/197 index a2547bc280..f07a9da136 100755 --- a/tests/qemu-iotests/197 +++ b/tests/qemu-iotests/197 @@ -122,6 +122,35 @@ $QEMU_IO -f qcow2 -C -c 'read 0 1024' "$TEST_WRAP" | _filter_qemu_io $QEMU_IO -f qcow2 -c map "$TEST_WRAP" _check_test_img +echo +echo '=== Copy-on-read with subclusters ===' +echo + +# Create base and top images 64K (1 cluster) each. Make subclusters enabled +# for the top image +_make_test_img 64K +IMGPROTO=file IMGFMT=qcow2 TEST_IMG_FILE="$TEST_WRAP" \ + _make_test_img --no-opts -o extended_l2=true -F "$IMGFMT" -b "$TEST_IMG" \ + 64K | _filter_img_create + +$QEMU_IO -c "write -P 0xaa 0 64k" "$TEST_IMG" | _filter_qemu_io + +# Allocate individual subclusters in the top image, and not the whole cluster +$QEMU_IO -c "write -P 0xbb 28K 2K" -c "write -P 0xcc 34K 2K" "$TEST_WRAP" \ + | _filter_qemu_io + +# Only 2 subclusters should be allocated in the top image at this point +$QEMU_IMG map "$TEST_WRAP" | _filter_qemu_img_map + +# Actual copy-on-read operation +$QEMU_IO -C -c "read -P 0xaa 30K 4K" "$TEST_WRAP" | _filter_qemu_io + +# And here we should have 4 subclusters allocated right in the middle of the +# top image. Make sure the whole cluster remains unallocated +$QEMU_IMG map "$TEST_WRAP" | _filter_qemu_img_map + +_check_test_img + # success, all done echo '*** done' status=0 diff --git a/tests/qemu-iotests/197.out b/tests/qemu-iotests/197.out index ad414c3b0e..8f34a30afe 100644 --- a/tests/qemu-iotests/197.out +++ b/tests/qemu-iotests/197.out @@ -31,4 +31,28 @@ read 1024/1024 bytes at offset 0 1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) 1 KiB (0x400) bytes allocated at offset 0 bytes (0x0) No errors were found on the image. + +=== Copy-on-read with subclusters === + +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=65536 +Formatting 'TEST_DIR/t.wrap.IMGFMT', fmt=IMGFMT size=65536 backing_file=TEST_DIR/t.IMGFMT backing_fmt=IMGFMT +wrote 65536/65536 bytes at offset 0 +64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 2048/2048 bytes at offset 28672 +2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 2048/2048 bytes at offset 34816 +2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Offset Length File +0 0x7000 TEST_DIR/t.IMGFMT +0x7000 0x800 TEST_DIR/t.wrap.IMGFMT +0x7800 0x1000 TEST_DIR/t.IMGFMT +0x8800 0x800 TEST_DIR/t.wrap.IMGFMT +0x9000 0x7000 TEST_DIR/t.IMGFMT +read 4096/4096 bytes at offset 30720 +4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Offset Length File +0 0x7000 TEST_DIR/t.IMGFMT +0x7000 0x2000 TEST_DIR/t.wrap.IMGFMT +0x9000 0x7000 TEST_DIR/t.IMGFMT +No errors were found on the image. *** done diff --git a/util/fdmon-io_uring.c b/util/fdmon-io_uring.c index 17ec18b7bd..16054c5ede 100644 --- a/util/fdmon-io_uring.c +++ b/util/fdmon-io_uring.c @@ -184,6 +184,7 @@ static void add_poll_remove_sqe(AioContext *ctx, AioHandler *node) #else io_uring_prep_poll_remove(sqe, node); #endif + io_uring_sqe_set_data(sqe, NULL); } /* Add a timeout that self-cancels when another cqe becomes ready */ @@ -197,6 +198,7 @@ static void add_timeout_sqe(AioContext *ctx, int64_t ns) sqe = get_sqe(ctx); io_uring_prep_timeout(sqe, &ts, 1, 0); + io_uring_sqe_set_data(sqe, NULL); } /* Add sqes from ctx->submit_list for submission */