06.02.2020 19:31, Max Reitz wrote:
On 03.02.20 14:42, Vladimir Sementsov-Ogievskiy wrote:
backup-top "supports" write-unchanged, by skipping CBW operation in
backup_top_co_pwritev. But it forgets to do the same in
backup_top_co_pwrite_zeroes, as well as declare support for
BDRV_REQ_WRITE_UNCHANGED.
Fix this, and, while being here, declare also support for flags
supported by source child.
Signed-off-by: Vladimir Sementsov-Ogievskiy <[email protected]>
---
v2: restrict flags propagation like it is done in other filters [Eric]
move state variable initialization to the top
block/backup-top.c | 32 ++++++++++++++++++++------------
1 file changed, 20 insertions(+), 12 deletions(-)
diff --git a/block/backup-top.c b/block/backup-top.c
index 9aed2eb4c0..a4cec60859 100644
--- a/block/backup-top.c
+++ b/block/backup-top.c
[...]
@@ -186,17 +190,21 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState
*source,
Error **errp)
{
Error *local_err = NULL;
- BDRVBackupTopState *state;
BlockDriverState *top = bdrv_new_open_driver(&bdrv_backup_top_filter,
filter_node_name,
BDRV_O_RDWR, errp);
+ BDRVBackupTopState *state = top->opaque;
if (!top) {
return NULL;
}
If top can be NULL, then we shouldn’t dereference it before (with
state = top->opaque).
Oh yes.
(Pulling up the initialization of @state is also unrelated to this
patch, I don’t exactly know why you’re doing it here.)
I just though, that it is small good style enhancement, but it isn't :)
Let's keep state variable handling as it was.
--
Best regards,
Vladimir
