fs: dcache scale d_unhashed

Protect d_unhashed(dentry) condition with d_lock. This means keeping
DCACHE_UNHASHED bit in synch with hash manipulations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

1 files changed, 3 insertions, 2 deletions

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 3ecf915a4550..571f270dca0f 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -136,6 +136,7 @@ more:
                         fi->at_end = 1;
                         goto out_unlock;
                 }
+                spin_lock(&dentry->d_lock);
                 if (!d_unhashed(dentry) && dentry->d_inode &&
                     ceph_snap(dentry->d_inode) != CEPH_SNAPDIR &&
                     ceph_ino(dentry->d_inode) != CEPH_INO_CEPH &&
@@ -145,13 +146,13 @@ more:
                      dentry->d_name.len, dentry->d_name.name, di->offset,
                      filp->f_pos, d_unhashed(dentry) ? " unhashed" : "",
                      !dentry->d_inode ? " null" : "");
+                spin_unlock(&dentry->d_lock);
                 p = p->prev;
                 dentry = list_entry(p, struct dentry, d_u.d_child);
                 di = ceph_dentry(dentry);
         }
 
-        spin_lock(&dentry->d_lock);
-        dentry->d_count++;
+        dget_dlock(dentry);
         spin_unlock(&dentry->d_lock);
         spin_unlock(&dcache_lock);