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Diffstat (limited to 'block/qcow2.c')
-rw-r--r--block/qcow2.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/block/qcow2.c b/block/qcow2.c
index 41b195d..ad46c03 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1281,6 +1281,26 @@ static int qcow2_make_empty(BlockDriverState *bs)
return 0;
}
+static coroutine_fn int qcow2_co_write_zeroes(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors)
+{
+ int ret;
+ BDRVQcowState *s = bs->opaque;
+
+ /* Emulate misaligned zero writes */
+ if (sector_num % s->cluster_sectors || nb_sectors % s->cluster_sectors) {
+ return -ENOTSUP;
+ }
+
+ /* Whatever is left can use real zero clusters */
+ qemu_co_mutex_lock(&s->lock);
+ ret = qcow2_zero_clusters(bs, sector_num << BDRV_SECTOR_BITS,
+ nb_sectors);
+ qemu_co_mutex_unlock(&s->lock);
+
+ return ret;
+}
+
static coroutine_fn int qcow2_co_discard(BlockDriverState *bs,
int64_t sector_num, int nb_sectors)
{
@@ -1558,6 +1578,7 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_co_writev = qcow2_co_writev,
.bdrv_co_flush_to_os = qcow2_co_flush_to_os,
+ .bdrv_co_write_zeroes = qcow2_co_write_zeroes,
.bdrv_co_discard = qcow2_co_discard,
.bdrv_truncate = qcow2_truncate,
.bdrv_write_compressed = qcow2_write_compressed,