[PATCH 32/51] [GFS2] Correct lock ordering in unlink

swhiteho
2007-10-04T09:29:43Z

From: Steven Whitehouse <swhiteho@redhat.com>

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>

diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 5b8b994..2cbe5a3 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;
}
--
1.5.1.2