ShuriZma
/
xemu
mirror of https://github.com/xemu-project/xemu.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

block/io: bdrv_co_do_copy_on_readv: use and support qiov_offset 

Use and support new API in bdrv_co_do_copy_on_readv. Note that in case
of allocated-in-top we need to shrink read size to MIN(..) by hand, as
pre-patch this was actually done implicitly by qemu_iovec_concat (and
we used local_qiov.size).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190604161514.262241-6-vsementsov@virtuozzo.com
Message-Id: <20190604161514.262241-6-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2019-06-04 19:15:07 +03:00 committed by Stefan Hajnoczi
parent ac850bf099
commit 1143ec5ebf
1 changed files with 9 additions and 9 deletions
block
io.c

18
block/io.c
View File

@ -1227,7 +1227,7 @@ bdrv_driver_pwritev_compressed(BlockDriverState *bs, uint64_t offset,
static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child, static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,
int64_t offset, unsigned int bytes, QEMUIOVector *qiov, int64_t offset, unsigned int bytes, QEMUIOVector *qiov,
int flags) size_t qiov_offset, int flags)
{ {
BlockDriverState *bs = child->bs; BlockDriverState *bs = child->bs;
@ -1239,7 +1239,6 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,
void *bounce_buffer; void *bounce_buffer;
BlockDriver *drv = bs->drv; BlockDriver *drv = bs->drv;
QEMUIOVector local_qiov;
int64_t cluster_offset; int64_t cluster_offset;
int64_t cluster_bytes; int64_t cluster_bytes;
size_t skip_bytes; size_t skip_bytes;
@ -1302,6 +1301,8 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,
assert(skip_bytes < pnum); assert(skip_bytes < pnum);
if (ret <= 0) { if (ret <= 0) {
QEMUIOVector local_qiov;
/* Must copy-on-read; use the bounce buffer */ /* Must copy-on-read; use the bounce buffer */
pnum = MIN(pnum, MAX_BOUNCE_BUFFER); pnum = MIN(pnum, MAX_BOUNCE_BUFFER);
qemu_iovec_init_buf(&local_qiov, bounce_buffer, pnum); qemu_iovec_init_buf(&local_qiov, bounce_buffer, pnum);
@ -1339,16 +1340,15 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,
} }
if (!(flags & BDRV_REQ_PREFETCH)) { if (!(flags & BDRV_REQ_PREFETCH)) {
qemu_iovec_from_buf(qiov, progress, bounce_buffer + skip_bytes, qemu_iovec_from_buf(qiov, qiov_offset + progress,
bounce_buffer + skip_bytes,
pnum - skip_bytes); pnum - skip_bytes);
} }
} else if (!(flags & BDRV_REQ_PREFETCH)) { } else if (!(flags & BDRV_REQ_PREFETCH)) {
/* Read directly into the destination */ /* Read directly into the destination */
qemu_iovec_init(&local_qiov, qiov->niov); ret = bdrv_driver_preadv(bs, offset + progress,
qemu_iovec_concat(&local_qiov, qiov, progress, pnum - skip_bytes); MIN(pnum - skip_bytes, bytes - progress),
ret = bdrv_driver_preadv(bs, offset + progress, local_qiov.size, qiov, qiov_offset + progress, 0);
&local_qiov, 0, 0);
qemu_iovec_destroy(&local_qiov);
if (ret < 0) { if (ret < 0) {
goto err; goto err;
} }
@ -1422,7 +1422,7 @@ static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child,
} }
if (!ret || pnum != bytes) { if (!ret || pnum != bytes) {
ret = bdrv_co_do_copy_on_readv(child, offset, bytes, qiov, flags); ret = bdrv_co_do_copy_on_readv(child, offset, bytes, qiov, 0, flags);
goto out; goto out;
} else if (flags & BDRV_REQ_PREFETCH) { } else if (flags & BDRV_REQ_PREFETCH) {
goto out; goto out;