[CIFS] Finish up of case-insensitive dentry handling for cifs. This
[linux-2.6] / fs / cifs / link.c
1 /*
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
31 int
32 cifs_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
51         down(&inode->i_sb->s_vfs_rename_sem);
52         fromName = build_path_from_dentry(old_file, cifs_sb_target);
53         toName = build_path_from_dentry(direntry, cifs_sb_target);
54         up(&inode->i_sb->s_vfs_rename_sem);
55         if((fromName == NULL) || (toName == NULL)) {
56                 rc = -ENOMEM;
57                 goto cifs_hl_exit;
58         }
59
60         if (cifs_sb_target->tcon->ses->capabilities & CAP_UNIX)
61                 rc = CIFSUnixCreateHardLink(xid, pTcon, fromName, toName,
62                                             cifs_sb_target->local_nls, 
63                                             cifs_sb_target->mnt_cifs_flags &
64                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
65         else {
66                 rc = CIFSCreateHardLink(xid, pTcon, fromName, toName,
67                                         cifs_sb_target->local_nls, 
68                                         cifs_sb_target->mnt_cifs_flags &
69                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
70                 if(rc == -EIO)
71                         rc = -EOPNOTSUPP;  
72         }
73
74 /* if (!rc)     */
75         {
76                 /*   renew_parental_timestamps(old_file);
77                    inode->i_nlink++;
78                    mark_inode_dirty(inode);
79                    d_instantiate(direntry, inode); */
80                 /* BB add call to either mark inode dirty or refresh its data and timestamp to current time */
81         }
82         d_drop(direntry);       /* force new lookup from server */
83         cifsInode = CIFS_I(old_file->d_inode);
84         cifsInode->time = 0;    /* will force revalidate to go get info when needed */
85
86 cifs_hl_exit:
87         if (fromName)
88                 kfree(fromName);
89         if (toName)
90                 kfree(toName);
91         FreeXid(xid);
92         return rc;
93 }
94
95 void *
96 cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
97 {
98         struct inode *inode = direntry->d_inode;
99         int rc = -EACCES;
100         int xid;
101         char *full_path = NULL;
102         char * target_path = ERR_PTR(-ENOMEM);
103         struct cifs_sb_info *cifs_sb;
104         struct cifsTconInfo *pTcon;
105
106         xid = GetXid();
107
108         cifs_sb = CIFS_SB(inode->i_sb);
109         pTcon = cifs_sb->tcon;
110
111         down(&direntry->d_sb->s_vfs_rename_sem);
112         full_path = build_path_from_dentry(direntry, cifs_sb);
113         up(&direntry->d_sb->s_vfs_rename_sem);
114
115         if (!full_path)
116                 goto out_no_free;
117
118         cFYI(1, ("Full path: %s inode = 0x%p", full_path, inode));
119         target_path = kmalloc(PATH_MAX, GFP_KERNEL);
120         if (!target_path) {
121                 target_path = ERR_PTR(-ENOMEM);
122                 goto out;
123         }
124
125 /* BB add read reparse point symlink code and Unix extensions symlink code here BB */
126         if (pTcon->ses->capabilities & CAP_UNIX)
127                 rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
128                                              target_path,
129                                              PATH_MAX-1,
130                                              cifs_sb->local_nls);
131         else {
132                 /* rc = CIFSSMBQueryReparseLinkInfo */
133                 /* BB Add code to Query ReparsePoint info */
134                 /* BB Add MAC style xsymlink check here if enabled */
135         }
136
137         if (rc == 0) {
138
139 /* BB Add special case check for Samba DFS symlinks */
140
141                 target_path[PATH_MAX-1] = 0;
142         } else {
143                 kfree(target_path);
144                 target_path = ERR_PTR(rc);
145         }
146
147 out:
148         kfree(full_path);
149 out_no_free:
150         FreeXid(xid);
151         nd_set_link(nd, target_path);
152         return NULL;    /* No cookie */
153 }
154
155 int
156 cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
157 {
158         int rc = -EOPNOTSUPP;
159         int xid;
160         struct cifs_sb_info *cifs_sb;
161         struct cifsTconInfo *pTcon;
162         char *full_path = NULL;
163         struct inode *newinode = NULL;
164
165         xid = GetXid();
166
167         cifs_sb = CIFS_SB(inode->i_sb);
168         pTcon = cifs_sb->tcon;
169
170         down(&inode->i_sb->s_vfs_rename_sem);
171         full_path = build_path_from_dentry(direntry, cifs_sb);
172         up(&inode->i_sb->s_vfs_rename_sem);
173
174         if(full_path == NULL) {
175                 FreeXid(xid);
176                 return -ENOMEM;
177         }
178
179         cFYI(1, ("Full path: %s ", full_path));
180         cFYI(1, ("symname is %s", symname));
181
182         /* BB what if DFS and this volume is on different share? BB */
183         if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
184                 rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
185                                            cifs_sb->local_nls);
186         /* else
187            rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,cifs_sb_target->local_nls); */
188
189         if (rc == 0) {
190                 if (pTcon->ses->capabilities & CAP_UNIX)
191                         rc = cifs_get_inode_info_unix(&newinode, full_path,
192                                                       inode->i_sb,xid);
193                 else
194                         rc = cifs_get_inode_info(&newinode, full_path, NULL,
195                                                  inode->i_sb,xid);
196
197                 if (rc != 0) {
198                         cFYI(1,
199                              ("Create symlink worked but get_inode_info failed with rc = %d ",
200                               rc));
201                 } else {
202                         if (pTcon->nocase)
203                                 direntry->d_op = &cifs_ci_dentry_ops;
204                         else
205                                 direntry->d_op = &cifs_dentry_ops;
206                         d_instantiate(direntry, newinode);
207                 }
208         }
209
210         if (full_path)
211                 kfree(full_path);
212         FreeXid(xid);
213         return rc;
214 }
215
216 int
217 cifs_readlink(struct dentry *direntry, char __user *pBuffer, int buflen)
218 {
219         struct inode *inode = direntry->d_inode;
220         int rc = -EACCES;
221         int xid;
222         int oplock = FALSE;
223         struct cifs_sb_info *cifs_sb;
224         struct cifsTconInfo *pTcon;
225         char *full_path = NULL;
226         char *tmp_path =  NULL;
227         char * tmpbuffer;
228         unsigned char * referrals = NULL;
229         int num_referrals = 0;
230         int len;
231         __u16 fid;
232
233         xid = GetXid();
234         cifs_sb = CIFS_SB(inode->i_sb);
235         pTcon = cifs_sb->tcon;
236
237 /* BB would it be safe against deadlock to grab this sem 
238       even though rename itself grabs the sem and calls lookup? */
239 /*       down(&inode->i_sb->s_vfs_rename_sem);*/
240         full_path = build_path_from_dentry(direntry, cifs_sb);
241 /*       up(&inode->i_sb->s_vfs_rename_sem);*/
242
243         if(full_path == NULL) {
244                 FreeXid(xid);
245                 return -ENOMEM;
246         }
247
248         cFYI(1,
249              ("Full path: %s inode = 0x%p pBuffer = 0x%p buflen = %d",
250               full_path, inode, pBuffer, buflen));
251         if(buflen > PATH_MAX)
252                 len = PATH_MAX;
253         else
254                 len = buflen;
255         tmpbuffer = kmalloc(len,GFP_KERNEL);   
256         if(tmpbuffer == NULL) {
257                 if (full_path)
258                         kfree(full_path);
259                 FreeXid(xid);
260                 return -ENOMEM;
261         }
262
263 /* BB add read reparse point symlink code and Unix extensions symlink code here BB */
264         if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
265                 rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
266                                 tmpbuffer,
267                                 len - 1,
268                                 cifs_sb->local_nls);
269         else {
270                 rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_OPEN, GENERIC_READ,
271                                 OPEN_REPARSE_POINT,&fid, &oplock, NULL, 
272                                 cifs_sb->local_nls, 
273                                 cifs_sb->mnt_cifs_flags & 
274                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
275                 if(!rc) {
276                         rc = CIFSSMBQueryReparseLinkInfo(xid, pTcon, full_path,
277                                 tmpbuffer,
278                                 len - 1, 
279                                 fid,
280                                 cifs_sb->local_nls);
281                         if(CIFSSMBClose(xid, pTcon, fid)) {
282                                 cFYI(1,("Error closing junction point (open for ioctl)"));
283                         }
284                         if(rc == -EIO) {
285                                 /* Query if DFS Junction */
286                                 tmp_path =
287                                         kmalloc(MAX_TREE_SIZE + MAX_PATHCONF + 1,
288                                                 GFP_KERNEL);
289                                 if (tmp_path) {
290                                         strncpy(tmp_path, pTcon->treeName, MAX_TREE_SIZE);
291                                         strncat(tmp_path, full_path, MAX_PATHCONF);
292                                         rc = get_dfs_path(xid, pTcon->ses, tmp_path,
293                                                 cifs_sb->local_nls,
294                                                 &num_referrals, &referrals,
295                                                 cifs_sb->mnt_cifs_flags &
296                                                     CIFS_MOUNT_MAP_SPECIAL_CHR);
297                                         cFYI(1,("Get DFS for %s rc = %d ",tmp_path, rc));
298                                         if((num_referrals == 0) && (rc == 0))
299                                                 rc = -EACCES;
300                                         else {
301                                                 cFYI(1,("num referral: %d",num_referrals));
302                                                 if(referrals) {
303                                                         cFYI(1,("referral string: %s ",referrals));
304                                                         strncpy(tmpbuffer, referrals, len-1);                            
305                                                 }
306                                         }
307                                         if(referrals)
308                                                 kfree(referrals);
309                                         kfree(tmp_path);
310 }
311                                 /* BB add code like else decode referrals then memcpy to
312                                   tmpbuffer and free referrals string array BB */
313                         }
314                 }
315         }
316         /* BB Anything else to do to handle recursive links? */
317         /* BB Should we be using page ops here? */
318
319         /* BB null terminate returned string in pBuffer? BB */
320         if (rc == 0) {
321                 rc = vfs_readlink(direntry, pBuffer, len, tmpbuffer);
322                 cFYI(1,
323                      ("vfs_readlink called from cifs_readlink returned %d",
324                       rc));
325         }
326
327         if (tmpbuffer) {
328                 kfree(tmpbuffer);
329         }
330         if (full_path) {
331                 kfree(full_path);
332         }
333         FreeXid(xid);
334         return rc;
335 }
336
337 void cifs_put_link(struct dentry *direntry, struct nameidata *nd, void *cookie)
338 {
339         char *p = nd_get_link(nd);
340         if (!IS_ERR(p))
341                 kfree(p);
342 }