block: generalize BlockLimits handling to cover bdrv_aio_discard too

bdrv_co_discard is only covering drivers which have a .bdrv_co_discard()
implementation, but not those with .bdrv_aio_discard(). Not very nice,
and easy to avoid.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Paolo Bonzini 2013-11-22 13:39:43 +01:00 committed by Stefan Hajnoczi
parent af057fe740
commit d51e9fe505

96
block.c
View File

@ -4302,6 +4302,8 @@ static void coroutine_fn bdrv_discard_co_entry(void *opaque)
int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
int nb_sectors)
{
int max_discard;
if (!bs->drv) {
return -ENOMEDIUM;
} else if (bdrv_check_request(bs, sector_num, nb_sectors)) {
@ -4317,55 +4319,55 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
return 0;
}
if (bs->drv->bdrv_co_discard) {
int max_discard = bs->bl.max_discard ?
bs->bl.max_discard : MAX_DISCARD_DEFAULT;
while (nb_sectors > 0) {
int ret;
int num = nb_sectors;
/* align request */
if (bs->bl.discard_alignment &&
num >= bs->bl.discard_alignment &&
sector_num % bs->bl.discard_alignment) {
if (num > bs->bl.discard_alignment) {
num = bs->bl.discard_alignment;
}
num -= sector_num % bs->bl.discard_alignment;
}
/* limit request size */
if (num > max_discard) {
num = max_discard;
}
ret = bs->drv->bdrv_co_discard(bs, sector_num, num);
if (ret) {
return ret;
}
sector_num += num;
nb_sectors -= num;
}
return 0;
} else if (bs->drv->bdrv_aio_discard) {
BlockDriverAIOCB *acb;
CoroutineIOCompletion co = {
.coroutine = qemu_coroutine_self(),
};
acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,
bdrv_co_io_em_complete, &co);
if (acb == NULL) {
return -EIO;
} else {
qemu_coroutine_yield();
return co.ret;
}
} else {
if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_discard) {
return 0;
}
max_discard = bs->bl.max_discard ? bs->bl.max_discard : MAX_DISCARD_DEFAULT;
while (nb_sectors > 0) {
int ret;
int num = nb_sectors;
/* align request */
if (bs->bl.discard_alignment &&
num >= bs->bl.discard_alignment &&
sector_num % bs->bl.discard_alignment) {
if (num > bs->bl.discard_alignment) {
num = bs->bl.discard_alignment;
}
num -= sector_num % bs->bl.discard_alignment;
}
/* limit request size */
if (num > max_discard) {
num = max_discard;
}
if (bs->drv->bdrv_co_discard) {
ret = bs->drv->bdrv_co_discard(bs, sector_num, num);
} else {
BlockDriverAIOCB *acb;
CoroutineIOCompletion co = {
.coroutine = qemu_coroutine_self(),
};
acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,
bdrv_co_io_em_complete, &co);
if (acb == NULL) {
return -EIO;
} else {
qemu_coroutine_yield();
ret = co.ret;
}
}
if (ret) {
return ret;
}
sector_num += num;
nb_sectors -= num;
}
return 0;
}
int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)