block: Convert BB interface to byte-based discards

Change sector-based blk_discard(), blk_co_discard(), and
blk_aio_discard() to instead be byte-based blk_pdiscard(),
blk_co_pdiscard(), and blk_aio_pdiscard().  NBD gets a lot
simpler now that ignoring the unaligned portion of a
byte-based discard request is handled under the hood by
the block layer.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468624988-423-6-git-send-email-eblake@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Eric Blake 2016-07-15 17:22:54 -06:00 committed by Stefan Hajnoczi
parent 60ebac16bc
commit 1c6c4bb7f0
8 changed files with 36 additions and 46 deletions

View file

@ -139,15 +139,14 @@ BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset,
BlockCompletionFunc *cb, void *opaque);
BlockAIOCB *blk_aio_flush(BlockBackend *blk,
BlockCompletionFunc *cb, void *opaque);
BlockAIOCB *blk_aio_discard(BlockBackend *blk,
int64_t sector_num, int nb_sectors,
BlockCompletionFunc *cb, void *opaque);
BlockAIOCB *blk_aio_pdiscard(BlockBackend *blk, int64_t offset, int count,
BlockCompletionFunc *cb, void *opaque);
void blk_aio_cancel(BlockAIOCB *acb);
void blk_aio_cancel_async(BlockAIOCB *acb);
int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf);
BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
BlockCompletionFunc *cb, void *opaque);
int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
int blk_co_pdiscard(BlockBackend *blk, int64_t offset, int count);
int blk_co_flush(BlockBackend *blk);
int blk_flush(BlockBackend *blk);
int blk_flush_all(void);
@ -207,7 +206,7 @@ int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset,
int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
const uint8_t *buf, int nb_sectors);
int blk_truncate(BlockBackend *blk, int64_t offset);
int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors);
int blk_pdiscard(BlockBackend *blk, int64_t offset, int count);
int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,
int64_t pos, int size);
int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size);