mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

block: Introduce bdrv_driver_pwritev()

Browse Source 
This is a function that simply calls into the block driver for doing a
write, providing the byte granularity interface we want to eventually
have everywhere, and using whatever interface that driver supports.

This one is a bit more interesting than the version for reads: It adds
support for .bdrv_co_writev_flags() everywhere, so that drivers
implementing this function can drop .bdrv_co_writev() now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
This commit is contained in:
Kevin Wolf 2016-04-25 12:13:39 +02:00
parent 166fe96051
commit 78a07294d5
4 changed files with 36 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
block/io.c
View File

@ -812,6 +812,36 @@ static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs,
return drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov);
}
static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs,
uint64_t offset, uint64_t bytes,
QEMUIOVector *qiov, int flags)
{
BlockDriver *drv = bs->drv;
int64_t sector_num = offset >> BDRV_SECTOR_BITS;
unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS;
int ret;
assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
assert((bytes >> BDRV_SECTOR_BITS) <= BDRV_REQUEST_MAX_SECTORS);
if (drv->bdrv_co_writev_flags) {
ret = drv->bdrv_co_writev_flags(bs, sector_num, nb_sectors, qiov,
flags);
} else {
assert(drv->supported_write_flags == 0);
ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
}
if (ret == 0 && (flags & BDRV_REQ_FUA) &&
!(drv->supported_write_flags & BDRV_REQ_FUA))
{
ret = bdrv_co_flush(bs);
}
return ret;
}
static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs,
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
{
@ -863,8 +893,9 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs,
/* This does not change the data on the disk, it is not necessary
* to flush even in cache=writethrough mode.
*/
ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors,
&bounce_qiov);
ret = bdrv_driver_pwritev(bs, cluster_sector_num * BDRV_SECTOR_SIZE,
cluster_nb_sectors * BDRV_SECTOR_SIZE,
&bounce_qiov, 0);
}
if (ret < 0) {
@ -1152,7 +1183,8 @@ static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs,
}
qemu_iovec_init_external(&qiov, &iov, 1);
ret = drv->bdrv_co_writev(bs, sector_num, num, &qiov);
ret = bdrv_driver_pwritev(bs, sector_num * BDRV_SECTOR_SIZE,
num * BDRV_SECTOR_SIZE, &qiov, 0);
/* Keep bounce buffer around if it is big enough for all
* all future requests.
@ -1212,23 +1244,12 @@ static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs,
} else if (flags & BDRV_REQ_ZERO_WRITE) {
bdrv_debug_event(bs, BLKDBG_PWRITEV_ZERO);
ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors, flags);
} else if (drv->bdrv_co_writev_flags) {
bdrv_debug_event(bs, BLKDBG_PWRITEV);
ret = drv->bdrv_co_writev_flags(bs, sector_num, nb_sectors, qiov,
flags);
} else {
assert(drv->supported_write_flags == 0);
bdrv_debug_event(bs, BLKDBG_PWRITEV);
ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
ret = bdrv_driver_pwritev(bs, offset, bytes, qiov, flags);
}
bdrv_debug_event(bs, BLKDBG_PWRITEV_DONE);
if (ret == 0 && (flags & BDRV_REQ_FUA) &&
!(drv->supported_write_flags & BDRV_REQ_FUA))
{
ret = bdrv_co_flush(bs);
}
bdrv_set_dirty(bs, sector_num, nb_sectors);
if (bs->wr_highest_offset < offset + bytes) {

8
block/iscsi.c
View File

@ -513,13 +513,6 @@ retry:
return 0;
}
static int coroutine_fn
iscsi_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
QEMUIOVector *iov)
{
return iscsi_co_writev_flags(bs, sector_num, nb_sectors, iov, 0);
}
static bool iscsi_allocationmap_is_allocated(IscsiLun *iscsilun,
int64_t sector_num, int nb_sectors)
@ -1847,7 +1840,6 @@ static BlockDriver bdrv_iscsi = {
.bdrv_co_discard = iscsi_co_discard,
.bdrv_co_write_zeroes = iscsi_co_write_zeroes,
.bdrv_co_readv = iscsi_co_readv,
.bdrv_co_writev = iscsi_co_writev,
.bdrv_co_writev_flags = iscsi_co_writev_flags,
.supported_write_flags = BDRV_REQ_FUA,
.bdrv_co_flush_to_disk = iscsi_co_flush,

9
block/nbd.c
View File

@ -374,12 +374,6 @@ static int nbd_co_writev_flags(BlockDriverState *bs, int64_t sector_num,
return ret;
}
static int nbd_co_writev(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, QEMUIOVector *qiov)
{
return nbd_co_writev_flags(bs, sector_num, nb_sectors, qiov, 0);
}
static int nbd_co_flush(BlockDriverState *bs)
{
return nbd_client_co_flush(bs);
@ -476,7 +470,6 @@ static BlockDriver bdrv_nbd = {
.bdrv_parse_filename = nbd_parse_filename,
.bdrv_file_open = nbd_open,
.bdrv_co_readv = nbd_co_readv,
.bdrv_co_writev = nbd_co_writev,
.bdrv_co_writev_flags = nbd_co_writev_flags,
.supported_write_flags = BDRV_REQ_FUA,
.bdrv_close = nbd_close,
@ -496,7 +489,6 @@ static BlockDriver bdrv_nbd_tcp = {
.bdrv_parse_filename = nbd_parse_filename,
.bdrv_file_open = nbd_open,
.bdrv_co_readv = nbd_co_readv,
.bdrv_co_writev = nbd_co_writev,
.bdrv_co_writev_flags = nbd_co_writev_flags,
.supported_write_flags = BDRV_REQ_FUA,
.bdrv_close = nbd_close,
@ -516,7 +508,6 @@ static BlockDriver bdrv_nbd_unix = {
.bdrv_parse_filename = nbd_parse_filename,
.bdrv_file_open = nbd_open,
.bdrv_co_readv = nbd_co_readv,
.bdrv_co_writev = nbd_co_writev,
.bdrv_co_writev_flags = nbd_co_writev_flags,
.supported_write_flags = BDRV_REQ_FUA,
.bdrv_close = nbd_close,

8
block/raw_bsd.c
View File

@ -116,13 +116,6 @@ fail:
return ret;
}
static int coroutine_fn
raw_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
QEMUIOVector *qiov)
{
return raw_co_writev_flags(bs, sector_num, nb_sectors, qiov, 0);
}
static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs,
int64_t sector_num,
int nb_sectors, int *pnum,
@ -256,7 +249,6 @@ BlockDriver bdrv_raw = {
.bdrv_close = &raw_close,
.bdrv_create = &raw_create,
.bdrv_co_readv = &raw_co_readv,
.bdrv_co_writev = &raw_co_writev,
.bdrv_co_writev_flags = &raw_co_writev_flags,
.supported_write_flags = BDRV_REQ_FUA,
.bdrv_co_write_zeroes = &raw_co_write_zeroes,