This will allow copy on write operations where the overwritten part of
the cluster is not aligned to sector boundaries.
Signed-off-by: Kevin Wolf <kw...@redhat.com>
---
block/qcow2-cluster.c | 37 +++++++++++++++++--------------------
1 file changed, 17 insertions(+), 20 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 9fb7f9f..5d04eb7 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -391,21 +391,17 @@ int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t
sector_num,
}
static int coroutine_fn copy_sectors(BlockDriverState *bs,
- uint64_t start_sect,
+ uint64_t src_cluster_offset,
uint64_t cluster_offset,
- int n_start, int n_end)
+ int offset_in_cluster,
+ int bytes)
{
BDRVQcow2State *s = bs->opaque;
QEMUIOVector qiov;
struct iovec iov;
- int n, ret;
-
- n = n_end - n_start;
- if (n <= 0) {
- return 0;
- }
+ int ret;
- iov.iov_len = n * BDRV_SECTOR_SIZE;
+ iov.iov_len = bytes;
iov.iov_base = qemu_try_blockalign(bs, iov.iov_len);
if (iov.iov_base == NULL) {
return -ENOMEM;
@@ -424,18 +420,20 @@ static int coroutine_fn copy_sectors(BlockDriverState *bs,
* interface. This avoids double I/O throttling and request tracking,
* which can lead to deadlock when block layer copy-on-read is enabled.
*/
- ret = bs->drv->bdrv_co_preadv(bs, (start_sect + n_start) *
BDRV_SECTOR_SIZE,
- n * BDRV_SECTOR_SIZE, &qiov, 0);
+ ret = bs->drv->bdrv_co_preadv(bs, src_cluster_offset + offset_in_cluster,
+ bytes, &qiov, 0);
if (ret < 0) {
goto out;
}
if (bs->encrypted) {
Error *err = NULL;
+ int sector = (cluster_offset + offset_in_cluster) >> BDRV_SECTOR_BITS;
assert(s->cipher);
- if (qcow2_encrypt_sectors(s, start_sect + n_start,
- iov.iov_base, iov.iov_base, n,
- true, &err) < 0) {
+ assert((offset_in_cluster & BDRV_SECTOR_MASK) == 0);
+ assert((bytes & ~BDRV_SECTOR_MASK) == 0);
+ if (qcow2_encrypt_sectors(s, sector, iov.iov_base, iov.iov_base,
+ bytes >> BDRV_SECTOR_BITS, true, &err) < 0) {
ret = -EIO;
error_free(err);
goto out;
@@ -443,14 +441,14 @@ static int coroutine_fn copy_sectors(BlockDriverState *bs,
}
ret = qcow2_pre_write_overlap_check(bs, 0,
- cluster_offset + n_start * BDRV_SECTOR_SIZE, n * BDRV_SECTOR_SIZE);
+ cluster_offset + offset_in_cluster, bytes);
if (ret < 0) {
goto out;
}
BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE);
- ret = bdrv_co_writev(bs->file->bs, (cluster_offset >> 9) + n_start, n,
- &qiov);
+ ret = bdrv_co_pwritev(bs->file->bs, cluster_offset + offset_in_cluster,
+ bytes, &qiov, 0);
if (ret < 0) {
goto out;
}
@@ -743,9 +741,8 @@ static int perform_cow(BlockDriverState *bs, QCowL2Meta *m,
Qcow2COWRegion *r)
}
qemu_co_mutex_unlock(&s->lock);
- ret = copy_sectors(bs, m->offset / BDRV_SECTOR_SIZE, m->alloc_offset,
- r->offset / BDRV_SECTOR_SIZE,
- r->offset / BDRV_SECTOR_SIZE + r->nb_sectors);
+ ret = copy_sectors(bs, m->offset, m->alloc_offset,
+ r->offset, r->nb_sectors * BDRV_SECTOR_SIZE);
qemu_co_mutex_lock(&s->lock);
if (ret < 0) {
--
1.8.3.1
