1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * This file contians vfs dentry ops for the 9P2000 protocol.
4 *
5 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
6 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
7 */
8
9 #include <linux/module.h>
10 #include <linux/errno.h>
11 #include <linux/fs.h>
12 #include <linux/file.h>
13 #include <linux/pagemap.h>
14 #include <linux/stat.h>
15 #include <linux/string.h>
16 #include <linux/inet.h>
17 #include <linux/namei.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <net/9p/9p.h>
21 #include <net/9p/client.h>
22
23 #include "v9fs.h"
24 #include "v9fs_vfs.h"
25 #include "fid.h"
26
27 /**
28 * v9fs_cached_dentry_delete - called when dentry refcount equals 0
29 * @dentry: dentry in question
30 *
31 */
v9fs_cached_dentry_delete(const struct dentry * dentry)32 static int v9fs_cached_dentry_delete(const struct dentry *dentry)
33 {
34 p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
35 dentry, dentry);
36
37 /* Don't cache negative dentries */
38 if (d_really_is_negative(dentry))
39 return 1;
40 return 0;
41 }
42
43 /**
44 * v9fs_dentry_release - called when dentry is going to be freed
45 * @dentry: dentry that is being release
46 *
47 */
48
v9fs_dentry_release(struct dentry * dentry)49 static void v9fs_dentry_release(struct dentry *dentry)
50 {
51 struct hlist_node *p, *n;
52
53 p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
54 dentry, dentry);
55 hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
56 p9_fid_put(hlist_entry(p, struct p9_fid, dlist));
57 dentry->d_fsdata = NULL;
58 }
59
v9fs_lookup_revalidate(struct dentry * dentry,unsigned int flags)60 static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
61 {
62 struct p9_fid *fid;
63 struct inode *inode;
64 struct v9fs_inode *v9inode;
65
66 if (flags & LOOKUP_RCU)
67 return -ECHILD;
68
69 inode = d_inode(dentry);
70 if (!inode)
71 goto out_valid;
72
73 v9inode = V9FS_I(inode);
74 if (v9inode->cache_validity & V9FS_INO_INVALID_ATTR) {
75 int retval;
76 struct v9fs_session_info *v9ses;
77
78 fid = v9fs_fid_lookup(dentry);
79 if (IS_ERR(fid))
80 return PTR_ERR(fid);
81
82 v9ses = v9fs_inode2v9ses(inode);
83 if (v9fs_proto_dotl(v9ses))
84 retval = v9fs_refresh_inode_dotl(fid, inode);
85 else
86 retval = v9fs_refresh_inode(fid, inode);
87 p9_fid_put(fid);
88
89 if (retval == -ENOENT)
90 return 0;
91 if (retval < 0)
92 return retval;
93 }
94 out_valid:
95 return 1;
96 }
97
98 const struct dentry_operations v9fs_cached_dentry_operations = {
99 .d_revalidate = v9fs_lookup_revalidate,
100 .d_weak_revalidate = v9fs_lookup_revalidate,
101 .d_delete = v9fs_cached_dentry_delete,
102 .d_release = v9fs_dentry_release,
103 };
104
105 const struct dentry_operations v9fs_dentry_operations = {
106 .d_delete = always_delete_dentry,
107 .d_release = v9fs_dentry_release,
108 };
109