blob: 11f265726db780e968e8084359696bc8a4c6446b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/cifs/link.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2003
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21#include <linux/fs.h>
22#include <linux/stat.h>
23#include <linux/namei.h>
24#include "cifsfs.h"
25#include "cifspdu.h"
26#include "cifsglob.h"
27#include "cifsproto.h"
28#include "cifs_debug.h"
29#include "cifs_fs_sb.h"
30
31int
32cifs_hardlink(struct dentry *old_file, struct inode *inode,
33 struct dentry *direntry)
34{
35 int rc = -EACCES;
36 int xid;
37 char *fromName = NULL;
38 char *toName = NULL;
39 struct cifs_sb_info *cifs_sb_target;
40 struct cifsTconInfo *pTcon;
41 struct cifsInodeInfo *cifsInode;
42
43 xid = GetXid();
44
45 cifs_sb_target = CIFS_SB(inode->i_sb);
46 pTcon = cifs_sb_target->tcon;
47
48/* No need to check for cross device links since server will do that
49 BB note DFS case in future though (when we may have to check) */
50
Steve French7f573562005-08-30 11:32:14 -070051 fromName = build_path_from_dentry(old_file);
52 toName = build_path_from_dentry(direntry);
Steve Frenchfb8c4b12007-07-10 01:16:18 +000053 if ((fromName == NULL) || (toName == NULL)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 rc = -ENOMEM;
55 goto cifs_hl_exit;
56 }
57
Steve Frenchc18c8422007-07-18 23:21:09 +000058/* if (cifs_sb_target->tcon->ses->capabilities & CAP_UNIX)*/
59 if (pTcon->unix_ext)
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 rc = CIFSUnixCreateHardLink(xid, pTcon, fromName, toName,
Steve Frenchfb8c4b12007-07-10 01:16:18 +000061 cifs_sb_target->local_nls,
Steve French737b7582005-04-28 22:41:06 -070062 cifs_sb_target->mnt_cifs_flags &
63 CIFS_MOUNT_MAP_SPECIAL_CHR);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 else {
65 rc = CIFSCreateHardLink(xid, pTcon, fromName, toName,
Steve Frenchfb8c4b12007-07-10 01:16:18 +000066 cifs_sb_target->local_nls,
Steve French737b7582005-04-28 22:41:06 -070067 cifs_sb_target->mnt_cifs_flags &
68 CIFS_MOUNT_MAP_SPECIAL_CHR);
Steve Frenchfb8c4b12007-07-10 01:16:18 +000069 if ((rc == -EIO) || (rc == -EINVAL))
70 rc = -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 }
72
Steve French31ec35d2006-11-16 20:54:20 +000073 d_drop(direntry); /* force new lookup from server of target */
74
75 /* if source file is cached (oplocked) revalidate will not go to server
76 until the file is closed or oplock broken so update nlinks locally */
Steve Frenchfb8c4b12007-07-10 01:16:18 +000077 if (old_file->d_inode) {
Steve French31ec35d2006-11-16 20:54:20 +000078 cifsInode = CIFS_I(old_file->d_inode);
Steve Frenchfb8c4b12007-07-10 01:16:18 +000079 if (rc == 0) {
Steve French31ec35d2006-11-16 20:54:20 +000080 old_file->d_inode->i_nlink++;
Steve French1b2b2122007-02-17 04:30:54 +000081/* BB should we make this contingent on superblock flag NOATIME? */
82/* old_file->d_inode->i_ctime = CURRENT_TIME;*/
Steve French31ec35d2006-11-16 20:54:20 +000083 /* parent dir timestamps will update from srv
84 within a second, would it really be worth it
85 to set the parent dir cifs inode time to zero
86 to force revalidate (faster) for it too? */
87 }
Steve Frenchfb8c4b12007-07-10 01:16:18 +000088 /* if not oplocked will force revalidate to get info
Steve French31ec35d2006-11-16 20:54:20 +000089 on source file from srv */
90 cifsInode->time = 0;
91
Steve Frenchfb8c4b12007-07-10 01:16:18 +000092 /* Will update parent dir timestamps from srv within a second.
Steve French31ec35d2006-11-16 20:54:20 +000093 Would it really be worth it to set the parent dir (cifs
94 inode) time field to zero to force revalidate on parent
Steve Frenchfb8c4b12007-07-10 01:16:18 +000095 directory faster ie
Steve French31ec35d2006-11-16 20:54:20 +000096 CIFS_I(inode)->time = 0; */
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070098
99cifs_hl_exit:
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800100 kfree(fromName);
101 kfree(toName);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 FreeXid(xid);
103 return rc;
104}
105
Linus Torvaldscc314ee2005-08-19 18:02:56 -0700106void *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
108{
109 struct inode *inode = direntry->d_inode;
110 int rc = -EACCES;
111 int xid;
112 char *full_path = NULL;
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000113 char *target_path = ERR_PTR(-ENOMEM);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 struct cifs_sb_info *cifs_sb;
115 struct cifsTconInfo *pTcon;
116
117 xid = GetXid();
118
Steve French7f573562005-08-30 11:32:14 -0700119 full_path = build_path_from_dentry(direntry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
121 if (!full_path)
122 goto out_no_free;
123
124 cFYI(1, ("Full path: %s inode = 0x%p", full_path, inode));
Steve French7f573562005-08-30 11:32:14 -0700125 cifs_sb = CIFS_SB(inode->i_sb);
126 pTcon = cifs_sb->tcon;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 target_path = kmalloc(PATH_MAX, GFP_KERNEL);
128 if (!target_path) {
129 target_path = ERR_PTR(-ENOMEM);
130 goto out;
131 }
132
Steve Frenchc18c8422007-07-18 23:21:09 +0000133 /* We could change this to:
134 if (pTcon->unix_ext)
135 but there does not seem any point in refusing to
136 get symlink info if we can, even if unix extensions
137 turned off for this mount */
138
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 if (pTcon->ses->capabilities & CAP_UNIX)
140 rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
141 target_path,
142 PATH_MAX-1,
143 cifs_sb->local_nls);
144 else {
Steve Frenchc18c8422007-07-18 23:21:09 +0000145 /* BB add read reparse point symlink code here */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 /* rc = CIFSSMBQueryReparseLinkInfo */
147 /* BB Add code to Query ReparsePoint info */
148 /* BB Add MAC style xsymlink check here if enabled */
149 }
150
151 if (rc == 0) {
152
153/* BB Add special case check for Samba DFS symlinks */
154
155 target_path[PATH_MAX-1] = 0;
156 } else {
157 kfree(target_path);
158 target_path = ERR_PTR(rc);
159 }
160
161out:
162 kfree(full_path);
163out_no_free:
164 FreeXid(xid);
165 nd_set_link(nd, target_path);
Linus Torvaldscc314ee2005-08-19 18:02:56 -0700166 return NULL; /* No cookie */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167}
168
169int
170cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
171{
172 int rc = -EOPNOTSUPP;
173 int xid;
174 struct cifs_sb_info *cifs_sb;
175 struct cifsTconInfo *pTcon;
176 char *full_path = NULL;
177 struct inode *newinode = NULL;
178
179 xid = GetXid();
180
181 cifs_sb = CIFS_SB(inode->i_sb);
182 pTcon = cifs_sb->tcon;
183
Steve French7f573562005-08-30 11:32:14 -0700184 full_path = build_path_from_dentry(direntry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000186 if (full_path == NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 FreeXid(xid);
188 return -ENOMEM;
189 }
190
Steve French26a21b92006-05-31 18:05:34 +0000191 cFYI(1, ("Full path: %s", full_path));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 cFYI(1, ("symname is %s", symname));
193
194 /* BB what if DFS and this volume is on different share? BB */
Steve Frenchc18c8422007-07-18 23:21:09 +0000195 if (pTcon->unix_ext)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
197 cifs_sb->local_nls);
198 /* else
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000199 rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
200 cifs_sb_target->local_nls); */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
202 if (rc == 0) {
Steve Frenchc18c8422007-07-18 23:21:09 +0000203 if (pTcon->unix_ext)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 rc = cifs_get_inode_info_unix(&newinode, full_path,
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000205 inode->i_sb, xid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 else
207 rc = cifs_get_inode_info(&newinode, full_path, NULL,
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000208 inode->i_sb, xid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
210 if (rc != 0) {
Steve French26a21b92006-05-31 18:05:34 +0000211 cFYI(1, ("Create symlink ok, getinodeinfo fail rc = %d",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 rc));
213 } else {
Steve Frenchb92327f2005-08-22 20:09:43 -0700214 if (pTcon->nocase)
215 direntry->d_op = &cifs_ci_dentry_ops;
216 else
217 direntry->d_op = &cifs_dentry_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 d_instantiate(direntry, newinode);
219 }
220 }
221
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800222 kfree(full_path);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 FreeXid(xid);
224 return rc;
225}
226
227int
228cifs_readlink(struct dentry *direntry, char __user *pBuffer, int buflen)
229{
230 struct inode *inode = direntry->d_inode;
231 int rc = -EACCES;
232 int xid;
233 int oplock = FALSE;
234 struct cifs_sb_info *cifs_sb;
235 struct cifsTconInfo *pTcon;
236 char *full_path = NULL;
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000237 char *tmp_path = NULL;
238 char *tmpbuffer;
239 unsigned char *referrals = NULL;
Steve French77159b42007-08-31 01:10:17 +0000240 unsigned int num_referrals = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 int len;
242 __u16 fid;
243
244 xid = GetXid();
245 cifs_sb = CIFS_SB(inode->i_sb);
246 pTcon = cifs_sb->tcon;
247
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000248/* BB would it be safe against deadlock to grab this sem
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 even though rename itself grabs the sem and calls lookup? */
Arjan van de Vena11f3a02006-03-23 03:00:33 -0800250/* mutex_lock(&inode->i_sb->s_vfs_rename_mutex);*/
Steve French7f573562005-08-30 11:32:14 -0700251 full_path = build_path_from_dentry(direntry);
Arjan van de Vena11f3a02006-03-23 03:00:33 -0800252/* mutex_unlock(&inode->i_sb->s_vfs_rename_mutex);*/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000254 if (full_path == NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 FreeXid(xid);
256 return -ENOMEM;
257 }
258
259 cFYI(1,
260 ("Full path: %s inode = 0x%p pBuffer = 0x%p buflen = %d",
261 full_path, inode, pBuffer, buflen));
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000262 if (buflen > PATH_MAX)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 len = PATH_MAX;
264 else
265 len = buflen;
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000266 tmpbuffer = kmalloc(len, GFP_KERNEL);
267 if (tmpbuffer == NULL) {
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800268 kfree(full_path);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 FreeXid(xid);
270 return -ENOMEM;
271 }
272
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000273/* BB add read reparse point symlink code and
274 Unix extensions symlink code here BB */
Steve Frenchc18c8422007-07-18 23:21:09 +0000275/* We could disable this based on pTcon->unix_ext flag instead ... but why? */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
277 rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
278 tmpbuffer,
279 len - 1,
280 cifs_sb->local_nls);
Steve French1bd5bbc2006-09-28 03:35:57 +0000281 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000282 cERROR(1, ("SFU style symlinks not implemented yet"));
Steve French1bd5bbc2006-09-28 03:35:57 +0000283 /* add open and read as in fs/cifs/inode.c */
Steve French1bd5bbc2006-09-28 03:35:57 +0000284 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_OPEN, GENERIC_READ,
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000286 OPEN_REPARSE_POINT, &fid, &oplock, NULL,
287 cifs_sb->local_nls,
288 cifs_sb->mnt_cifs_flags &
Steve French737b7582005-04-28 22:41:06 -0700289 CIFS_MOUNT_MAP_SPECIAL_CHR);
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000290 if (!rc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 rc = CIFSSMBQueryReparseLinkInfo(xid, pTcon, full_path,
292 tmpbuffer,
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000293 len - 1,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 fid,
295 cifs_sb->local_nls);
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000296 if (CIFSSMBClose(xid, pTcon, fid)) {
Steve French63135e02007-07-17 17:34:02 +0000297 cFYI(1, ("Error closing junction point "
298 "(open for ioctl)"));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 }
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000300 if (rc == -EIO) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 /* Query if DFS Junction */
302 tmp_path =
303 kmalloc(MAX_TREE_SIZE + MAX_PATHCONF + 1,
304 GFP_KERNEL);
305 if (tmp_path) {
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000306 strncpy(tmp_path, pTcon->treeName,
307 MAX_TREE_SIZE);
308 strncat(tmp_path, full_path,
309 MAX_PATHCONF);
310 rc = get_dfs_path(xid, pTcon->ses,
311 tmp_path,
Steve French737b7582005-04-28 22:41:06 -0700312 cifs_sb->local_nls,
313 &num_referrals, &referrals,
314 cifs_sb->mnt_cifs_flags &
315 CIFS_MOUNT_MAP_SPECIAL_CHR);
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000316 cFYI(1, ("Get DFS for %s rc = %d ",
317 tmp_path, rc));
318 if ((num_referrals == 0) && (rc == 0))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 rc = -EACCES;
320 else {
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000321 cFYI(1, ("num referral: %d",
322 num_referrals));
323 if (referrals) {
324 cFYI(1,("referral string: %s", referrals));
Steve French50c2f752007-07-13 00:33:32 +0000325 strncpy(tmpbuffer,
326 referrals,
327 len-1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 }
329 }
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800330 kfree(referrals);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 kfree(tmp_path);
332}
Steve Frenchfb8c4b12007-07-10 01:16:18 +0000333 /* BB add code like else decode referrals
334 then memcpy to tmpbuffer and free referrals
335 string array BB */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 }
337 }
338 }
339 /* BB Anything else to do to handle recursive links? */
340 /* BB Should we be using page ops here? */
341
342 /* BB null terminate returned string in pBuffer? BB */
343 if (rc == 0) {
344 rc = vfs_readlink(direntry, pBuffer, len, tmpbuffer);
345 cFYI(1,
346 ("vfs_readlink called from cifs_readlink returned %d",
347 rc));
348 }
349
Jesper Juhlf99d49a2005-11-07 01:01:34 -0800350 kfree(tmpbuffer);
351 kfree(full_path);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 FreeXid(xid);
353 return rc;
354}
355
Linus Torvaldscc314ee2005-08-19 18:02:56 -0700356void cifs_put_link(struct dentry *direntry, struct nameidata *nd, void *cookie)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357{
358 char *p = nd_get_link(nd);
359 if (!IS_ERR(p))
360 kfree(p);
361}