diff options
| author | Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> | 2022-02-15 13:16:09 +0100 |
|---|---|---|
| committer | Hanna Reitz <hreitz@redhat.com> | 2022-03-07 09:19:20 +0100 |
| commit | 45e62b464a5fa62f0f005b76f59ad587944cd55f (patch) | |
| tree | 6d36c058260d83f60888847b76cd19d017639b0e /block | |
| parent | b0ea6c98fa2431b9e24b3a53b8b42c960ccf3dba (diff) | |
block: fix preallocate filter: don't do unaligned preallocate requests
There is a bug in handling BDRV_REQ_NO_WAIT flag: we still may wait in
wait_serialising_requests() if request is unaligned. And this is
possible for the only user of this flag (preallocate filter) if
underlying file is unaligned to its request_alignment on start.
So, we have to fix preallocate filter to do only aligned preallocate
requests.
Next, we should fix generic block/io.c somehow. Keeping in mind that
preallocate is the only user of BDRV_REQ_NO_WAIT and that we have to
fix its behavior now, it seems more safe to just assert that we never
use BDRV_REQ_NO_WAIT with unaligned requests and add corresponding
comment. Let's do so.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20220215121609.38570-1-vsementsov@virtuozzo.com>
[hreitz: Rebased on block GS/IO split]
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/io.c | 4 | ||||
| -rw-r--r-- | block/preallocate.c | 15 |
2 files changed, 16 insertions, 3 deletions
diff --git a/block/io.c b/block/io.c index efc011ce65..8bee484463 100644 --- a/block/io.c +++ b/block/io.c @@ -2203,6 +2203,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child, padding = bdrv_init_padding(bs, offset, bytes, &pad); if (padding) { + assert(!(flags & BDRV_REQ_NO_WAIT)); bdrv_make_request_serialising(req, align); bdrv_padding_rmw_read(child, req, &pad, true); @@ -2339,6 +2340,7 @@ int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child, * serialize the request to prevent interactions of the * widened region with other transactions. */ + assert(!(flags & BDRV_REQ_NO_WAIT)); bdrv_make_request_serialising(&req, align); bdrv_padding_rmw_read(child, &req, &pad, false); } @@ -3387,6 +3389,8 @@ static int coroutine_fn bdrv_co_copy_range_internal( /* TODO We can support BDRV_REQ_NO_FALLBACK here */ assert(!(read_flags & BDRV_REQ_NO_FALLBACK)); assert(!(write_flags & BDRV_REQ_NO_FALLBACK)); + assert(!(read_flags & BDRV_REQ_NO_WAIT)); + assert(!(write_flags & BDRV_REQ_NO_WAIT)); if (!dst || !dst->bs || !bdrv_is_inserted(dst->bs)) { return -ENOMEDIUM; diff --git a/block/preallocate.c b/block/preallocate.c index 1d4233f730..e15cb8c74a 100644 --- a/block/preallocate.c +++ b/block/preallocate.c @@ -276,6 +276,10 @@ static bool coroutine_fn handle_write(BlockDriverState *bs, int64_t offset, int64_t end = offset + bytes; int64_t prealloc_start, prealloc_end; int ret; + uint32_t file_align = bs->file->bs->bl.request_alignment; + uint32_t prealloc_align = MAX(s->opts.prealloc_align, file_align); + + assert(QEMU_IS_ALIGNED(prealloc_align, file_align)); if (!has_prealloc_perms(bs)) { /* We don't have state neither should try to recover it */ @@ -320,9 +324,14 @@ static bool coroutine_fn handle_write(BlockDriverState *bs, int64_t offset, /* Now we want new preallocation, as request writes beyond s->file_end. */ - prealloc_start = want_merge_zero ? MIN(offset, s->file_end) : s->file_end; - prealloc_end = QEMU_ALIGN_UP(end + s->opts.prealloc_size, - s->opts.prealloc_align); + prealloc_start = QEMU_ALIGN_UP( + want_merge_zero ? MIN(offset, s->file_end) : s->file_end, + file_align); + prealloc_end = QEMU_ALIGN_UP( + MAX(prealloc_start, end) + s->opts.prealloc_size, + prealloc_align); + + want_merge_zero = want_merge_zero && (prealloc_start <= offset); ret = bdrv_co_pwrite_zeroes( bs->file, prealloc_start, prealloc_end - prealloc_start, |