@@ -1057,12 +1057,15 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset,
int alloc_n_start = offset_into_cluster(s, guest_offset)
>> BDRV_SECTOR_BITS;
int nb_sectors = MIN(requested_sectors, avail_sectors);
+ QCowL2Meta *old_m = *m;
*host_offset = alloc_cluster_offset;
*m = g_malloc0(sizeof(**m));
**m = (QCowL2Meta) {
+ .next = old_m,
+
.alloc_offset = *host_offset,
.offset = start_of_cluster(s, guest_offset),
.nb_clusters = nb_clusters,
@@ -824,7 +824,9 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
goto fail;
}
- if (l2meta != NULL) {
+ while (l2meta != NULL) {
+ QCowL2Meta *next;
+
ret = qcow2_alloc_cluster_link_l2(bs, l2meta);
if (ret < 0) {
goto fail;
@@ -837,8 +839,9 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
qemu_co_queue_restart_all(&l2meta->dependent_requests);
+ next = l2meta->next;
g_free(l2meta);
- l2meta = NULL;
+ l2meta = next;
}
remaining_sectors -= cur_nr_sectors;
@@ -851,12 +854,17 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
fail:
qemu_co_mutex_unlock(&s->lock);
- if (l2meta != NULL) {
+ while (l2meta != NULL) {
+ QCowL2Meta *next;
+
if (l2meta->nb_clusters != 0) {
QLIST_REMOVE(l2meta, next_in_flight);
}
qemu_co_queue_restart_all(&l2meta->dependent_requests);
+
+ next = l2meta->next;
g_free(l2meta);
+ l2meta = next;
}
qemu_iovec_destroy(&hd_qiov);
@@ -246,6 +246,9 @@ typedef struct QCowL2Meta
*/
Qcow2COWRegion cow_end;
+ /** Pointer to next L2Meta of the same write request */
+ struct QCowL2Meta *next;
+
QLIST_ENTRY(QCowL2Meta) next_in_flight;
} QCowL2Meta;
Instead of expecting a single l2meta, have a list of them. This allows to still have a single I/O request for the guest data, even though multiple l2meta may be needed in order to describe both a COW overwrite and a new cluster allocation (typical sequential write case). Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2-cluster.c | 3 +++ block/qcow2.c | 14 +++++++++++--- block/qcow2.h | 3 +++ 3 files changed, 17 insertions(+), 3 deletions(-)