GFS2: Unlock rindex mutex on glock error
[linux-2.6.git] / fs / gfs2 / dentry.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 #include <linux/spinlock.h>
11 #include <linux/completion.h>
12 #include <linux/buffer_head.h>
13 #include <linux/gfs2_ondisk.h>
14 #include <linux/namei.h>
15 #include <linux/crc32.h>
16
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "dir.h"
20 #include "glock.h"
21 #include "super.h"
22 #include "util.h"
23 #include "inode.h"
24
25 /**
26  * gfs2_drevalidate - Check directory lookup consistency
27  * @dentry: the mapping to check
28  * @nd:
29  *
30  * Check to make sure the lookup necessary to arrive at this inode from its
31  * parent is still good.
32  *
33  * Returns: 1 if the dentry is ok, 0 if it isn't
34  */
35
36 static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd)
37 {
38         struct dentry *parent;
39         struct gfs2_sbd *sdp;
40         struct gfs2_inode *dip;
41         struct inode *inode;
42         struct gfs2_holder d_gh;
43         struct gfs2_inode *ip = NULL;
44         int error;
45         int had_lock = 0;
46
47         if (nd && nd->flags & LOOKUP_RCU)
48                 return -ECHILD;
49
50         parent = dget_parent(dentry);
51         sdp = GFS2_SB(parent->d_inode);
52         dip = GFS2_I(parent->d_inode);
53         inode = dentry->d_inode;
54
55         if (inode) {
56                 if (is_bad_inode(inode))
57                         goto invalid;
58                 ip = GFS2_I(inode);
59         }
60
61         if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
62                 goto valid;
63
64         had_lock = (gfs2_glock_is_locked_by_me(dip->i_gl) != NULL);
65         if (!had_lock) {
66                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
67                 if (error)
68                         goto fail;
69         } 
70
71         error = gfs2_dir_check(parent->d_inode, &dentry->d_name, ip);
72         switch (error) {
73         case 0:
74                 if (!inode)
75                         goto invalid_gunlock;
76                 break;
77         case -ENOENT:
78                 if (!inode)
79                         goto valid_gunlock;
80                 goto invalid_gunlock;
81         default:
82                 goto fail_gunlock;
83         }
84
85 valid_gunlock:
86         if (!had_lock)
87                 gfs2_glock_dq_uninit(&d_gh);
88 valid:
89         dput(parent);
90         return 1;
91
92 invalid_gunlock:
93         if (!had_lock)
94                 gfs2_glock_dq_uninit(&d_gh);
95 invalid:
96         if (inode && S_ISDIR(inode->i_mode)) {
97                 if (have_submounts(dentry))
98                         goto valid;
99                 shrink_dcache_parent(dentry);
100         }
101         d_drop(dentry);
102         dput(parent);
103         return 0;
104
105 fail_gunlock:
106         gfs2_glock_dq_uninit(&d_gh);
107 fail:
108         dput(parent);
109         return 0;
110 }
111
112 static int gfs2_dhash(const struct dentry *dentry, const struct inode *inode,
113                 struct qstr *str)
114 {
115         str->hash = gfs2_disk_hash(str->name, str->len);
116         return 0;
117 }
118
119 static int gfs2_dentry_delete(const struct dentry *dentry)
120 {
121         struct gfs2_inode *ginode;
122
123         if (!dentry->d_inode)
124                 return 0;
125
126         ginode = GFS2_I(dentry->d_inode);
127         if (!ginode->i_iopen_gh.gh_gl)
128                 return 0;
129
130         if (test_bit(GLF_DEMOTE, &ginode->i_iopen_gh.gh_gl->gl_flags))
131                 return 1;
132
133         return 0;
134 }
135
136 const struct dentry_operations gfs2_dops = {
137         .d_revalidate = gfs2_drevalidate,
138         .d_hash = gfs2_dhash,
139         .d_delete = gfs2_dentry_delete,
140 };
141