[GFS2] Correct lock ordering in unlink

This patch corrects the lock ordering in unlink to be the same as
that in the rest of GFS2, i.e. parent -> child -> rgrp.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 20 insertions, 9 deletions

diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 5b8b994b9912..2cbe5a321e89 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -278,17 +278,25 @@ static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
         gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
 
 
-        error = gfs2_glock_nq_m(3, ghs);
+        error = gfs2_glock_nq(ghs); /* parent */
         if (error)
-                goto out;
+                goto out_parent;
+
+        error = gfs2_glock_nq(ghs + 1); /* child */
+        if (error)
+                goto out_child;
+
+        error = gfs2_glock_nq(ghs + 2); /* rgrp */
+        if (error)
+                goto out_rgrp;
 
         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
         if (error)
-                goto out_gunlock;
+                goto out_rgrp;
 
         error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
         if (error)
-                goto out_gunlock;
+                goto out_rgrp;
 
         error = gfs2_dir_del(dip, &dentry->d_name);
         if (error)
@@ -298,12 +306,15 @@ static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
 
 out_end_trans:
         gfs2_trans_end(sdp);
-out_gunlock:
-        gfs2_glock_dq_m(3, ghs);
-out:
-        gfs2_holder_uninit(ghs);
-        gfs2_holder_uninit(ghs + 1);
+        gfs2_glock_dq(ghs + 2);
+out_rgrp:
         gfs2_holder_uninit(ghs + 2);
+        gfs2_glock_dq(ghs + 1);
+out_child:
+        gfs2_holder_uninit(ghs + 1);
+        gfs2_glock_dq(ghs);
+out_parent:
+        gfs2_holder_uninit(ghs);
         gfs2_glock_dq_uninit(&ri_gh);
         return error;
 }