diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2016-03-04 14:52:32 +0100 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2016-03-30 11:59:32 +0200 |
| commit | b8816a43865822883ffc9b506e6243c7d986561a (patch) | |
| tree | 4fdf9fa912d75eac44a77bcf79c3eb51abc00e5f | |
| parent | aaa436f9982ebf3988c9a25661c96bca97b259b0 (diff) | |
block: Make backing files always writeback
First of all, we're generally not writing to backing files, but when we
do, it's in the context of block jobs which know very well when to flush
the image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
| -rw-r--r-- | block.c | 5 | ||||
| -rw-r--r-- | tests/qemu-iotests/142.out | 10 |
2 files changed, 8 insertions, 7 deletions
@@ -738,8 +738,9 @@ static void bdrv_backing_options(int *child_flags, QDict *child_options, { int flags = parent_flags; - /* The cache mode is inherited unmodified for backing files */ - qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_WB); + /* The cache mode is inherited unmodified for backing files; except WCE, + * which is only applied on the top level (BlockBackend) */ + qdict_set_default_str(child_options, BDRV_OPT_CACHE_WB, "on"); qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIRECT); qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FLUSH); diff --git a/tests/qemu-iotests/142.out b/tests/qemu-iotests/142.out index b555d5a255..abe94c3320 100644 --- a/tests/qemu-iotests/142.out +++ b/tests/qemu-iotests/142.out @@ -62,7 +62,7 @@ cache.direct=on on backing-file cache.writeback=off on none0 Cache mode: writethrough Cache mode: writeback - Cache mode: writethrough + Cache mode: writeback Cache mode: writeback cache.writeback=off on file @@ -143,7 +143,7 @@ cache.writeback=off on none0 Cache mode: writethrough Cache mode: writethrough Cache mode: writeback - Cache mode: writethrough + Cache mode: writeback Cache mode: writeback cache.writeback=off on file @@ -302,7 +302,7 @@ cache.direct=on on backing-file cache.writeback=off on none0 Cache mode: writethrough, direct Cache mode: writeback, direct - Cache mode: writethrough, direct + Cache mode: writeback, direct Cache mode: writeback, direct cache.writeback=off on file @@ -383,7 +383,7 @@ cache.writeback=off on none0 Cache mode: writeback, direct Cache mode: writethrough Cache mode: writeback - Cache mode: writethrough + Cache mode: writeback Cache mode: writeback cache.writeback=off on file @@ -718,7 +718,7 @@ cache.direct=on on backing-file cache.writeback=off on none0 Cache mode: writethrough Cache mode: writeback - Cache mode: writethrough, direct + Cache mode: writeback, direct Cache mode: writeback, direct cache.writeback=off on file |