1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * linux/fs/9p/vfs_dentry.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * This file contians vfs dentry ops for the 9P2000 protocol.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
8*4882a593Smuzhiyun * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <linux/module.h>
12*4882a593Smuzhiyun #include <linux/errno.h>
13*4882a593Smuzhiyun #include <linux/fs.h>
14*4882a593Smuzhiyun #include <linux/file.h>
15*4882a593Smuzhiyun #include <linux/pagemap.h>
16*4882a593Smuzhiyun #include <linux/stat.h>
17*4882a593Smuzhiyun #include <linux/string.h>
18*4882a593Smuzhiyun #include <linux/inet.h>
19*4882a593Smuzhiyun #include <linux/namei.h>
20*4882a593Smuzhiyun #include <linux/idr.h>
21*4882a593Smuzhiyun #include <linux/sched.h>
22*4882a593Smuzhiyun #include <linux/slab.h>
23*4882a593Smuzhiyun #include <net/9p/9p.h>
24*4882a593Smuzhiyun #include <net/9p/client.h>
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun #include "v9fs.h"
27*4882a593Smuzhiyun #include "v9fs_vfs.h"
28*4882a593Smuzhiyun #include "fid.h"
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun /**
31*4882a593Smuzhiyun * v9fs_cached_dentry_delete - called when dentry refcount equals 0
32*4882a593Smuzhiyun * @dentry: dentry in question
33*4882a593Smuzhiyun *
34*4882a593Smuzhiyun */
v9fs_cached_dentry_delete(const struct dentry * dentry)35*4882a593Smuzhiyun static int v9fs_cached_dentry_delete(const struct dentry *dentry)
36*4882a593Smuzhiyun {
37*4882a593Smuzhiyun p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
38*4882a593Smuzhiyun dentry, dentry);
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun /* Don't cache negative dentries */
41*4882a593Smuzhiyun if (d_really_is_negative(dentry))
42*4882a593Smuzhiyun return 1;
43*4882a593Smuzhiyun return 0;
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun /**
47*4882a593Smuzhiyun * v9fs_dentry_release - called when dentry is going to be freed
48*4882a593Smuzhiyun * @dentry: dentry that is being release
49*4882a593Smuzhiyun *
50*4882a593Smuzhiyun */
51*4882a593Smuzhiyun
v9fs_dentry_release(struct dentry * dentry)52*4882a593Smuzhiyun static void v9fs_dentry_release(struct dentry *dentry)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun struct hlist_node *p, *n;
55*4882a593Smuzhiyun p9_debug(P9_DEBUG_VFS, " dentry: %pd (%p)\n",
56*4882a593Smuzhiyun dentry, dentry);
57*4882a593Smuzhiyun hlist_for_each_safe(p, n, (struct hlist_head *)&dentry->d_fsdata)
58*4882a593Smuzhiyun p9_client_clunk(hlist_entry(p, struct p9_fid, dlist));
59*4882a593Smuzhiyun dentry->d_fsdata = NULL;
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun
v9fs_lookup_revalidate(struct dentry * dentry,unsigned int flags)62*4882a593Smuzhiyun static int v9fs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun struct p9_fid *fid;
65*4882a593Smuzhiyun struct inode *inode;
66*4882a593Smuzhiyun struct v9fs_inode *v9inode;
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun if (flags & LOOKUP_RCU)
69*4882a593Smuzhiyun return -ECHILD;
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun inode = d_inode(dentry);
72*4882a593Smuzhiyun if (!inode)
73*4882a593Smuzhiyun goto out_valid;
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun v9inode = V9FS_I(inode);
76*4882a593Smuzhiyun if (v9inode->cache_validity & V9FS_INO_INVALID_ATTR) {
77*4882a593Smuzhiyun int retval;
78*4882a593Smuzhiyun struct v9fs_session_info *v9ses;
79*4882a593Smuzhiyun fid = v9fs_fid_lookup(dentry);
80*4882a593Smuzhiyun if (IS_ERR(fid))
81*4882a593Smuzhiyun return PTR_ERR(fid);
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun v9ses = v9fs_inode2v9ses(inode);
84*4882a593Smuzhiyun if (v9fs_proto_dotl(v9ses))
85*4882a593Smuzhiyun retval = v9fs_refresh_inode_dotl(fid, inode);
86*4882a593Smuzhiyun else
87*4882a593Smuzhiyun retval = v9fs_refresh_inode(fid, inode);
88*4882a593Smuzhiyun if (retval == -ENOENT)
89*4882a593Smuzhiyun return 0;
90*4882a593Smuzhiyun if (retval < 0)
91*4882a593Smuzhiyun return retval;
92*4882a593Smuzhiyun }
93*4882a593Smuzhiyun out_valid:
94*4882a593Smuzhiyun return 1;
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun const struct dentry_operations v9fs_cached_dentry_operations = {
98*4882a593Smuzhiyun .d_revalidate = v9fs_lookup_revalidate,
99*4882a593Smuzhiyun .d_weak_revalidate = v9fs_lookup_revalidate,
100*4882a593Smuzhiyun .d_delete = v9fs_cached_dentry_delete,
101*4882a593Smuzhiyun .d_release = v9fs_dentry_release,
102*4882a593Smuzhiyun };
103*4882a593Smuzhiyun
104*4882a593Smuzhiyun const struct dentry_operations v9fs_dentry_operations = {
105*4882a593Smuzhiyun .d_delete = always_delete_dentry,
106*4882a593Smuzhiyun .d_release = v9fs_dentry_release,
107*4882a593Smuzhiyun };
108