haraldwolff/qemu-patch-raspberry4
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

block: reverse order for reopen commits

Browse source 
It's needed to fix reopening qcow2 with bitmaps to RW. Currently it
can't work, as qcow2 needs write access to file child, to mark bitmaps
in-image with IN_USE flag. But usually children goes after parents in
reopen queue and file child is still RO on qcow2 reopen commit. Reverse
reopen order to fix it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Max Reitz <mreitz@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-id: 20190927122355.7344-3-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2019-09-27 15:23:48 +03:00 committed by John Snow
parent 859443b0fb
commit fcd6a4f42d
1 changed files with 9 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
block.c
View file

@ -3486,10 +3486,16 @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp)
bs_entry->perms_checked = true;
}
/* If we reach this point, we have success and just need to apply the
* changes
/*
* If we reach this point, we have success and just need to apply the
* changes.
*
* Reverse order is used to comfort qcow2 driver: on commit it need to write
* IN_USE flag to the image, to mark bitmaps in the image as invalid. But
* children are usually goes after parents in reopen-queue, so go from last
* to first element.
*/
QTAILQ_FOREACH(bs_entry, bs_queue, entry) {
QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) {
bdrv_reopen_commit(&bs_entry->state);
}