@@ -693,7 +693,7 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
old_cluster[j++] = l2_table[l2_index + i];
l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
- (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
+ (i << s->cluster_bits)) | m->l2_entry_flags);
}
@@ -706,7 +706,7 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
* If this was a COW, we need to decrease the refcount of the old cluster.
* Also flush bs->file to get the right order for L2 and refcount update.
*/
- if (j != 0) {
+ if (!m->overwrite && j != 0) {
for (i = 0; i < j; i++) {
qcow2_free_any_clusters(bs, be64_to_cpu(old_cluster[i]), 1);
}
@@ -1006,6 +1006,9 @@ again:
.offset = nb_sectors * BDRV_SECTOR_SIZE,
.nb_sectors = avail_sectors - nb_sectors,
},
+
+ .l2_entry_flags = QCOW_OFLAG_COPIED,
+ .overwrite = false,
};
qemu_co_queue_init(&(*m)->dependent_requests);
QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight);
@@ -309,6 +309,12 @@ typedef struct QCowL2Meta
*/
CoQueue dependent_requests;
+ /* contains the flags to apply to the l2 entry */
+ uint64_t l2_entry_flags;
+
+ /* set to true if we are overwriting an L2 table entry */
+ bool overwrite;
+
/**
* The COW Region between the start of the first allocated cluster and the
* area the guest actually writes to.
Signed-off-by: Benoit Canet <benoit@irqsave.net> --- block/qcow2-cluster.c | 7 +++++-- block/qcow2.h | 6 ++++++ 2 files changed, 11 insertions(+), 2 deletions(-)