GFS2: Fix up jdata writepage/delete_inode
[linux-2.6.git] / fs / gfs2 / ops_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/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/crc32.h>
16 #include <linux/lm_interface.h>
17
18 #include "gfs2.h"
19 #include "incore.h"
20 #include "dir.h"
21 #include "glock.h"
22 #include "super.h"
23 #include "util.h"
24 #include "inode.h"
25
26 /**
27  * gfs2_drevalidate - Check directory lookup consistency
28  * @dentry: the mapping to check
29  * @nd:
30  *
31  * Check to make sure the lookup necessary to arrive at this inode from its
32  * parent is still good.
33  *
34  * Returns: 1 if the dentry is ok, 0 if it isn't
35  */
36
37 static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd)
38 {
39         struct dentry *parent = dget_parent(dentry);
40         struct gfs2_sbd *sdp = GFS2_SB(parent->d_inode);
41         struct gfs2_inode *dip = GFS2_I(parent->d_inode);
42         struct inode *inode = dentry->d_inode;
43         struct gfs2_holder d_gh;
44         struct gfs2_inode *ip = NULL;
45         int error;
46         int had_lock = 0;
47
48         if (inode) {
49                 if (is_bad_inode(inode))
50                         goto invalid;
51                 ip = GFS2_I(inode);
52         }
53
54         if (sdp->sd_args.ar_localcaching)
55                 goto valid;
56
57         had_lock = (gfs2_glock_is_locked_by_me(dip->i_gl) != NULL);
58         if (!had_lock) {
59                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
60                 if (error)
61                         goto fail;
62         } 
63
64         error = gfs2_dir_check(parent->d_inode, &dentry->d_name, ip);
65         switch (error) {
66         case 0:
67                 if (!inode)
68                         goto invalid_gunlock;
69                 break;
70         case -ENOENT:
71                 if (!inode)
72                         goto valid_gunlock;
73                 goto invalid_gunlock;
74         default:
75                 goto fail_gunlock;
76         }
77
78 valid_gunlock:
79         if (!had_lock)
80                 gfs2_glock_dq_uninit(&d_gh);
81 valid:
82         dput(parent);
83         return 1;
84
85 invalid_gunlock:
86         if (!had_lock)
87                 gfs2_glock_dq_uninit(&d_gh);
88 invalid:
89         if (inode && S_ISDIR(inode->i_mode)) {
90                 if (have_submounts(dentry))
91                         goto valid;
92                 shrink_dcache_parent(dentry);
93         }
94         d_drop(dentry);
95         dput(parent);
96         return 0;
97
98 fail_gunlock:
99         gfs2_glock_dq_uninit(&d_gh);
100 fail:
101         dput(parent);
102         return 0;
103 }
104
105 static int gfs2_dhash(struct dentry *dentry, struct qstr *str)
106 {
107         str->hash = gfs2_disk_hash(str->name, str->len);
108         return 0;
109 }
110
111 struct dentry_operations gfs2_dops = {
112         .d_revalidate = gfs2_drevalidate,
113         .d_hash = gfs2_dhash,
114 };
115