diff options
| author | Eric Blake <eblake@redhat.com> | 2019-03-28 23:27:49 -0500 |
|---|---|---|
| committer | Eric Blake <eblake@redhat.com> | 2019-04-01 08:46:52 -0500 |
| commit | 4841211e0d1628cd386b35835676d7f6f9a4fa9d (patch) | |
| tree | 1b8268090b537c4b264b2ba118b0d114297310a1 /block | |
| parent | 9cf638508c0090b33ada4155c7cbb684e08e5ee9 (diff) | |
block: Add bdrv_get_request_alignment()
The next patch needs access to a device's minimum permitted
alignment, since NBD wants to advertise this to clients. Add
an accessor function, borrowing from blk_get_max_transfer()
for accessing a backend's block limits.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20190329042750.14704-6-eblake@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/block-backend.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/block/block-backend.c b/block/block-backend.c index edad02a0f2..f78e82a707 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1764,6 +1764,13 @@ int blk_get_flags(BlockBackend *blk) } } +/* Returns the minimum request alignment, in bytes; guaranteed nonzero */ +uint32_t blk_get_request_alignment(BlockBackend *blk) +{ + BlockDriverState *bs = blk_bs(blk); + return bs ? bs->bl.request_alignment : BDRV_SECTOR_SIZE; +} + /* Returns the maximum transfer length, in bytes; guaranteed nonzero */ uint32_t blk_get_max_transfer(BlockBackend *blk) { |