d_prune_aliases() does not prune dentry that has non-zero reference
count. If we want trim_caps() to trim 'N' caps, the first 'N' inodes
in session->s_caps are all directories with child dentry, trim_caps()
can fail to trim anything.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: "Yan, Zheng" <zyan@xxxxxxxxxx>
---
fs/ceph/mds_client.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 80339e278ad8..da181acd4a61 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -1490,16 +1490,20 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
if ((used | wanted) & ~oissued & mine)
goto out; /* we need these caps */
- session->s_trim_caps--;
if (oissued) {
/* we aren't the only cap.. just remove us */
__ceph_remove_cap(cap, true);
+ session->s_trim_caps--;
} else {
+ int refs;
/* try dropping referring dentries */
spin_unlock(&ci->i_ceph_lock);
d_prune_aliases(inode);
+ refs = atomic_read(&inode->i_count);
+ if (refs == 1)
+ session->s_trim_caps--;
dout("trim_caps_cb %p cap %p pruned, count now %d\n",
- inode, cap, atomic_read(&inode->i_count));
+ inode, cap, refs);
return 0;
}
--
2.13.6