qga: ignore EBUSY when freezing a filesystem

the current implementation fails if we try to freeze an
already frozen filesystem. This can happen if a filesystem
is mounted more than once (e.g. with a bind mount).

Suggested-by: Christian Theune <ct@flyingcircus.io>
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
stable-2.9
Peter Lieven 2017-01-31 16:36:34 +01:00 committed by Michael Roth
parent 26de229657
commit ce2eb6c4a0
1 changed files with 4 additions and 1 deletions

View File

@ -1243,6 +1243,9 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
* filesystems may not implement fsfreeze for less obvious reasons.
* these will report EOPNOTSUPP. we simply ignore these when tallying
* the number of frozen filesystems.
* if a filesystem is mounted more than once (aka bind mount) a
* consecutive attempt to freeze an already frozen filesystem will
* return EBUSY.
*
* any other error means a failure to freeze a filesystem we
* expect to be freezable, so return an error in those cases
@ -1250,7 +1253,7 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
*/
ret = ioctl(fd, FIFREEZE);
if (ret == -1) {
if (errno != EOPNOTSUPP) {
if (errno != EOPNOTSUPP && errno != EBUSY) {
error_setg_errno(errp, errno, "failed to freeze %s",
mount->dirname);
close(fd);