diff options
| author | Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> | 2024-03-13 18:28:19 +0300 |
|---|---|---|
| committer | Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> | 2024-05-28 15:52:15 +0300 |
| commit | 507175197b06a24beb2369abe95b00172741c457 (patch) | |
| tree | cdb4365e00cb427a86cf7fa82c2621798aaf5c8b | |
| parent | 137b4d4bd506bd42c18718f3f8b43a2d7c3346a8 (diff) | |
block/copy-before-write: support unligned snapshot-discard
First thing that crashes on unligned access here is
bdrv_reset_dirty_bitmap(). Correct way is to align-down the
snapshot-discard request.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Message-Id: <20240313152822.626493-3-vsementsov@yandex-team.ru>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
| -rw-r--r-- | block/copy-before-write.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/block/copy-before-write.c b/block/copy-before-write.c index 3e3af30c08..6d89af0b29 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -325,14 +325,24 @@ static int coroutine_fn GRAPH_RDLOCK cbw_co_pdiscard_snapshot(BlockDriverState *bs, int64_t offset, int64_t bytes) { BDRVCopyBeforeWriteState *s = bs->opaque; + uint32_t cluster_size = block_copy_cluster_size(s->bcs); + int64_t aligned_offset = QEMU_ALIGN_UP(offset, cluster_size); + int64_t aligned_end = QEMU_ALIGN_DOWN(offset + bytes, cluster_size); + int64_t aligned_bytes; + + if (aligned_end <= aligned_offset) { + return 0; + } + aligned_bytes = aligned_end - aligned_offset; WITH_QEMU_LOCK_GUARD(&s->lock) { - bdrv_reset_dirty_bitmap(s->access_bitmap, offset, bytes); + bdrv_reset_dirty_bitmap(s->access_bitmap, aligned_offset, + aligned_bytes); } - block_copy_reset(s->bcs, offset, bytes); + block_copy_reset(s->bcs, aligned_offset, aligned_bytes); - return bdrv_co_pdiscard(s->target, offset, bytes); + return bdrv_co_pdiscard(s->target, aligned_offset, aligned_bytes); } static void GRAPH_RDLOCK cbw_refresh_filename(BlockDriverState *bs) |