ceph: only queue capsnap if caps are dirty
We used to go into this branch if i_wrbuffer_ref_head was non-zero. This
was an ancient check from before we were careful about dealing with all
kinds of caps (and not just dirty pages). It is cleaner to only queue a
capsnap if there is an actual dirty cap. If we are racing with...
something...we will end up here with ci->i_wrbuffer_refs but no dirty
caps.
Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index ac030c9..e264371 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -465,9 +465,8 @@
cap_snap. lucky us. */
dout("queue_cap_snap %p already pending\n", inode);
kfree(capsnap);
- } else if (ci->i_wrbuffer_ref_head ||
- (dirty & (CEPH_CAP_AUTH_EXCL|CEPH_CAP_XATTR_EXCL|
- CEPH_CAP_FILE_EXCL|CEPH_CAP_FILE_WR))) {
+ } else if (dirty & (CEPH_CAP_AUTH_EXCL|CEPH_CAP_XATTR_EXCL|
+ CEPH_CAP_FILE_EXCL|CEPH_CAP_FILE_WR)) {
struct ceph_snap_context *snapc = ci->i_head_snapc;
/*
@@ -480,7 +479,6 @@
dout("queue_cap_snap %p cap_snap %p queuing under %p %s\n",
inode, capsnap, snapc, ceph_cap_string(dirty));
ihold(inode);
- BUG_ON(dirty == 0);
atomic_set(&capsnap->nref, 1);
capsnap->ci = ci;