1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/*
* Copyright IBM Corporation, 2010
* Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2.1 of the GNU Lesser General Public License
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
*/
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/uio.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "fid.h"
#include "xattr.h"
ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
void *buffer, size_t buffer_size)
{
ssize_t retval;
u64 attr_size;
struct p9_fid *attr_fid;
struct kvec kvec = {.iov_base = buffer, .iov_len = buffer_size};
struct iov_iter to;
int err;
iov_iter_kvec(&to, READ, &kvec, 1, buffer_size);
attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
if (IS_ERR(attr_fid)) {
retval = PTR_ERR(attr_fid);
p9_debug(P9_DEBUG_VFS, "p9_client_attrwalk failed %zd\n",
retval);
return retval;
}
if (attr_size > buffer_size) {
if (!buffer_size) /* request to get the attr_size */
retval = attr_size;
else
retval = -ERANGE;
} else {
iov_iter_truncate(&to, attr_size);
retval = p9_client_read(attr_fid, 0, &to, &err);
if (err)
retval = err;
}
p9_client_clunk(attr_fid);
return retval;
}
/*
* v9fs_xattr_get()
*
* Copy an extended attribute into the buffer
* provided, or compute the buffer size required.
* Buffer is NULL to compute the size of the buffer required.
*
* Returns a negative error number on failure, or the number of bytes
* used / required on success.
*/
ssize_t v9fs_xattr_get(struct dentry *dentry, const char *name,
void *buffer, size_t buffer_size)
{
struct p9_fid *fid;
int ret;
p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu\n",
name, buffer_size);
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
ret = v9fs_fid_xattr_get(fid, name, buffer, buffer_size);
p9_client_clunk(fid);
return ret;
}
/*
* v9fs_xattr_set()
*
* Create, replace or remove an extended attribute for this inode. Buffer
* is NULL to remove an existing extended attribute, and non-NULL to
* either replace an existing extended attribute, or create a new extended
* attribute. The flags XATTR_REPLACE and XATTR_CREATE
* specify that an extended attribute must exist and must not exist
* previous to the call, respectively.
*
* Returns 0, or a negative error number on failure.
*/
int v9fs_xattr_set(struct dentry *dentry, const char *name,
const void *value, size_t value_len, int flags)
{
int ret;
struct p9_fid *fid;
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
ret = v9fs_fid_xattr_set(fid, name, value, value_len, flags);
p9_client_clunk(fid);
return ret;
}
int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
const void *value, size_t value_len, int flags)
{
struct kvec kvec = {.iov_base = (void *)value, .iov_len = value_len};
struct iov_iter from;
int retval, err;
iov_iter_kvec(&from, WRITE, &kvec, 1, value_len);
p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu flags = %d\n",
name, value_len, flags);
/* Clone it */
fid = clone_fid(fid);
if (IS_ERR(fid))
return PTR_ERR(fid);
/*
* On success fid points to xattr
*/
retval = p9_client_xattrcreate(fid, name, value_len, flags);
if (retval < 0)
p9_debug(P9_DEBUG_VFS, "p9_client_xattrcreate failed %d\n",
retval);
else
p9_client_write(fid, 0, &from, &retval);
err = p9_client_clunk(fid);
if (!retval && err)
retval = err;
return retval;
}
ssize_t v9fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
{
return v9fs_xattr_get(dentry, NULL, buffer, buffer_size);
}
static int v9fs_xattr_handler_get(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *inode,
const char *name, void *buffer, size_t size)
{
const char *full_name = xattr_full_name(handler, name);
return v9fs_xattr_get(dentry, full_name, buffer, size);
}
static int v9fs_xattr_handler_set(const struct xattr_handler *handler,
struct user_namespace *mnt_userns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
{
const char *full_name = xattr_full_name(handler, name);
return v9fs_xattr_set(dentry, full_name, value, size, flags);
}
static struct xattr_handler v9fs_xattr_user_handler = {
.prefix = XATTR_USER_PREFIX,
.get = v9fs_xattr_handler_get,
.set = v9fs_xattr_handler_set,
};
static struct xattr_handler v9fs_xattr_trusted_handler = {
.prefix = XATTR_TRUSTED_PREFIX,
.get = v9fs_xattr_handler_get,
.set = v9fs_xattr_handler_set,
};
#ifdef CONFIG_9P_FS_SECURITY
static struct xattr_handler v9fs_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.get = v9fs_xattr_handler_get,
.set = v9fs_xattr_handler_set,
};
#endif
const struct xattr_handler *v9fs_xattr_handlers[] = {
&v9fs_xattr_user_handler,
&v9fs_xattr_trusted_handler,
#ifdef CONFIG_9P_FS_POSIX_ACL
&v9fs_xattr_acl_access_handler,
&v9fs_xattr_acl_default_handler,
#endif
#ifdef CONFIG_9P_FS_SECURITY
&v9fs_xattr_security_handler,
#endif
NULL
};
|
