Patchwork [9/9] block: for HMP commit() operations on 'all', skip non-COW drives

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Submitter Stefan Hajnoczi
Date March 4, 2013, 9:15 a.m.
Message ID <1362388531-32305-10-git-send-email-stefanha@redhat.com>
Download mbox | patch
Permalink /patch/224659/
State New
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Comments

Stefan Hajnoczi - March 4, 2013, 9:15 a.m.
From: Jeff Cody <jcody@redhat.com>

During a commit of 'all' using the HMP non-live commit, the operation
is aborted and returns error on the first error enountered.  When
non-COW drives are in use (e.g. ejected floppy, cdrom, or drives without
a backing parent), that means a commit all will return an error of either
-ENOMEDIUM or -ENOTSUP.  This is not desirable, so for the 'all' commit
case, only attempt the commit if both bs->drv and bs->backing_hd are
present.

More succinctly: 'commit all' now means a commit on all COW drives.

This means an individual commit to a specific non-COW drive will still
return the appropriate error (-ENOMEDIUM if eject / not present, -ENOTSUP
if no backing file).

Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Patch

diff --git a/block.c b/block.c
index 4582961..124a9eb 100644
--- a/block.c
+++ b/block.c
@@ -1640,9 +1640,11 @@  int bdrv_commit_all(void)
     BlockDriverState *bs;
 
     QTAILQ_FOREACH(bs, &bdrv_states, list) {
-        int ret = bdrv_commit(bs);
-        if (ret < 0) {
-            return ret;
+        if (bs->drv && bs->backing_hd) {
+            int ret = bdrv_commit(bs);
+            if (ret < 0) {
+                return ret;
+            }
         }
     }
     return 0;