Merge master.kernel.org:/pub/scm/linux/kernel/git/paulus/powerpc-merge
[linux-2.6] / fs / cifs / dir.c
1 /*
2  *   fs/cifs/dir.c
3  *
4  *   vfs operations that deal with dentries
5  * 
6  *   Copyright (C) International Business Machines  Corp., 2002,2003
7  *   Author(s): Steve French (sfrench@us.ibm.com)
8  *
9  *   This library is free software; you can redistribute it and/or modify
10  *   it under the terms of the GNU Lesser General Public License as published
11  *   by the Free Software Foundation; either version 2.1 of the License, or
12  *   (at your option) any later version.
13  *
14  *   This library is distributed in the hope that it will be useful,
15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
17  *   the GNU Lesser General Public License for more details.
18  *
19  *   You should have received a copy of the GNU Lesser General Public License
20  *   along with this library; if not, write to the Free Software
21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  */
23 #include <linux/fs.h>
24 #include <linux/stat.h>
25 #include <linux/slab.h>
26 #include <linux/namei.h>
27 #include "cifsfs.h"
28 #include "cifspdu.h"
29 #include "cifsglob.h"
30 #include "cifsproto.h"
31 #include "cifs_debug.h"
32 #include "cifs_fs_sb.h"
33
34 void
35 renew_parental_timestamps(struct dentry *direntry)
36 {
37         /* BB check if there is a way to get the kernel to do this or if we really need this */
38         do {
39                 direntry->d_time = jiffies;
40                 direntry = direntry->d_parent;
41         } while (!IS_ROOT(direntry));   
42 }
43
44 /* Note: caller must free return buffer */
45 char *
46 build_path_from_dentry(struct dentry *direntry)
47 {
48         struct dentry *temp;
49         int namelen = 0;
50         char *full_path;
51         char dirsep = CIFS_DIR_SEP(CIFS_SB(direntry->d_sb));
52
53         if(direntry == NULL)
54                 return NULL;  /* not much we can do if dentry is freed and
55                 we need to reopen the file after it was closed implicitly
56                 when the server crashed */
57
58 cifs_bp_rename_retry:
59         for (temp = direntry; !IS_ROOT(temp);) {
60                 namelen += (1 + temp->d_name.len);
61                 temp = temp->d_parent;
62                 if(temp == NULL) {
63                         cERROR(1,("corrupt dentry"));
64                         return NULL;
65                 }
66         }
67
68         full_path = kmalloc(namelen+1, GFP_KERNEL);
69         if(full_path == NULL)
70                 return full_path;
71         full_path[namelen] = 0; /* trailing null */
72
73         for (temp = direntry; !IS_ROOT(temp);) {
74                 namelen -= 1 + temp->d_name.len;
75                 if (namelen < 0) {
76                         break;
77                 } else {
78                         full_path[namelen] = dirsep;
79                         strncpy(full_path + namelen + 1, temp->d_name.name,
80                                 temp->d_name.len);
81                         cFYI(0, (" name: %s ", full_path + namelen));
82                 }
83                 temp = temp->d_parent;
84                 if(temp == NULL) {
85                         cERROR(1,("corrupt dentry"));
86                         kfree(full_path);
87                         return NULL;
88                 }
89         }
90         if (namelen != 0) {
91                 cERROR(1,
92                        ("We did not end path lookup where we expected namelen is %d",
93                         namelen));
94                 /* presumably this is only possible if we were racing with a rename 
95                 of one of the parent directories  (we can not lock the dentries
96                 above us to prevent this, but retrying should be harmless) */
97                 kfree(full_path);
98                 namelen = 0;
99                 goto cifs_bp_rename_retry;
100         }
101
102         return full_path;
103 }
104
105 /* char * build_wildcard_path_from_dentry(struct dentry *direntry)
106 {
107         if(full_path == NULL)
108                 return full_path;
109
110         full_path[namelen] = '\\';
111         full_path[namelen+1] = '*';
112         full_path[namelen+2] = 0;
113 BB remove above eight lines BB */
114
115 /* Inode operations in similar order to how they appear in the Linux file fs.h */
116
117 int
118 cifs_create(struct inode *inode, struct dentry *direntry, int mode,
119                 struct nameidata *nd)
120 {
121         int rc = -ENOENT;
122         int xid;
123         int oplock = 0;
124         int desiredAccess = GENERIC_READ | GENERIC_WRITE;
125         __u16 fileHandle;
126         struct cifs_sb_info *cifs_sb;
127         struct cifsTconInfo *pTcon;
128         char *full_path = NULL;
129         FILE_ALL_INFO * buf = NULL;
130         struct inode *newinode = NULL;
131         struct cifsFileInfo * pCifsFile = NULL;
132         struct cifsInodeInfo * pCifsInode;
133         int disposition = FILE_OVERWRITE_IF;
134         int write_only = FALSE;
135
136         xid = GetXid();
137
138         cifs_sb = CIFS_SB(inode->i_sb);
139         pTcon = cifs_sb->tcon;
140
141         down(&direntry->d_sb->s_vfs_rename_sem);
142         full_path = build_path_from_dentry(direntry);
143         up(&direntry->d_sb->s_vfs_rename_sem);
144         if(full_path == NULL) {
145                 FreeXid(xid);
146                 return -ENOMEM;
147         }
148
149         if(nd && (nd->flags & LOOKUP_OPEN)) {
150                 int oflags = nd->intent.open.flags;
151
152                 desiredAccess = 0;
153                 if (oflags & FMODE_READ)
154                         desiredAccess |= GENERIC_READ;
155                 if (oflags & FMODE_WRITE) {
156                         desiredAccess |= GENERIC_WRITE;
157                         if (!(oflags & FMODE_READ))
158                                 write_only = TRUE;
159                 }
160
161                 if((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
162                         disposition = FILE_CREATE;
163                 else if((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
164                         disposition = FILE_OVERWRITE_IF;
165                 else if((oflags & O_CREAT) == O_CREAT)
166                         disposition = FILE_OPEN_IF;
167                 else {
168                         cFYI(1,("Create flag not set in create function"));
169                 }
170         }
171
172         /* BB add processing to set equivalent of mode - e.g. via CreateX with ACLs */
173         if (oplockEnabled)
174                 oplock = REQ_OPLOCK;
175
176         buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL);
177         if(buf == NULL) {
178                 kfree(full_path);
179                 FreeXid(xid);
180                 return -ENOMEM;
181         }
182
183         rc = CIFSSMBOpen(xid, pTcon, full_path, disposition,
184                          desiredAccess, CREATE_NOT_DIR,
185                          &fileHandle, &oplock, buf, cifs_sb->local_nls,
186                          cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
187         if(rc == -EIO) {
188                 /* old server, retry the open legacy style */
189                 rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
190                         desiredAccess, CREATE_NOT_DIR,
191                         &fileHandle, &oplock, buf, cifs_sb->local_nls,
192                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
193         } 
194         if (rc) {
195                 cFYI(1, ("cifs_create returned 0x%x ", rc));
196         } else {
197                 /* If Open reported that we actually created a file
198                 then we now have to set the mode if possible */
199                 if ((cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
200                         (oplock & CIFS_CREATE_ACTION))
201                         if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
202                                 CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
203                                         (__u64)current->euid,
204                                         (__u64)current->egid,
205                                         0 /* dev */,
206                                         cifs_sb->local_nls, 
207                                         cifs_sb->mnt_cifs_flags & 
208                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
209                         } else {
210                                 CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
211                                         (__u64)-1,
212                                         (__u64)-1,
213                                         0 /* dev */,
214                                         cifs_sb->local_nls,
215                                         cifs_sb->mnt_cifs_flags & 
216                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
217                         }
218                 else {
219                         /* BB implement mode setting via Windows security descriptors */
220                         /* eg CIFSSMBWinSetPerms(xid,pTcon,full_path,mode,-1,-1,local_nls);*/
221                         /* could set r/o dos attribute if mode & 0222 == 0 */
222                 }
223
224         /* BB server might mask mode so we have to query for Unix case*/
225                 if (pTcon->ses->capabilities & CAP_UNIX)
226                         rc = cifs_get_inode_info_unix(&newinode, full_path,
227                                                  inode->i_sb,xid);
228                 else {
229                         rc = cifs_get_inode_info(&newinode, full_path,
230                                                  buf, inode->i_sb,xid);
231                         if(newinode)
232                                 newinode->i_mode = mode;
233                 }
234
235                 if (rc != 0) {
236                         cFYI(1,
237                              ("Create worked but get_inode_info failed rc = %d",
238                               rc));
239                 } else {
240                         if (pTcon->nocase)
241                                 direntry->d_op = &cifs_ci_dentry_ops;
242                         else
243                                 direntry->d_op = &cifs_dentry_ops;
244                         d_instantiate(direntry, newinode);
245                 }
246                 if((nd->flags & LOOKUP_OPEN) == FALSE) {
247                         /* mknod case - do not leave file open */
248                         CIFSSMBClose(xid, pTcon, fileHandle);
249                 } else if(newinode) {
250                         pCifsFile =
251                            kmalloc(sizeof (struct cifsFileInfo), GFP_KERNEL);
252                         
253                         if(pCifsFile == NULL)
254                                 goto cifs_create_out;
255                         memset((char *)pCifsFile, 0,
256                                sizeof (struct cifsFileInfo));
257                         pCifsFile->netfid = fileHandle;
258                         pCifsFile->pid = current->tgid;
259                         pCifsFile->pInode = newinode;
260                         pCifsFile->invalidHandle = FALSE;
261                         pCifsFile->closePend     = FALSE;
262                         init_MUTEX(&pCifsFile->fh_sem);
263                         /* set the following in open now 
264                                 pCifsFile->pfile = file; */
265                         write_lock(&GlobalSMBSeslock);
266                         list_add(&pCifsFile->tlist,&pTcon->openFileList);
267                         pCifsInode = CIFS_I(newinode);
268                         if(pCifsInode) {
269                                 /* if readable file instance put first in list*/
270                                 if (write_only == TRUE) {
271                                         list_add_tail(&pCifsFile->flist,
272                                                 &pCifsInode->openFileList);
273                                 } else {
274                                         list_add(&pCifsFile->flist,
275                                                 &pCifsInode->openFileList);
276                                 }
277                                 if((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
278                                         pCifsInode->clientCanCacheAll = TRUE;
279                                         pCifsInode->clientCanCacheRead = TRUE;
280                                         cFYI(1,("Exclusive Oplock for inode %p",
281                                                 newinode));
282                                 } else if((oplock & 0xF) == OPLOCK_READ)
283                                         pCifsInode->clientCanCacheRead = TRUE;
284                         }
285                         write_unlock(&GlobalSMBSeslock);
286                 }
287         } 
288 cifs_create_out:
289         kfree(buf);
290         kfree(full_path);
291         FreeXid(xid);
292         return rc;
293 }
294
295 int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, dev_t device_number) 
296 {
297         int rc = -EPERM;
298         int xid;
299         struct cifs_sb_info *cifs_sb;
300         struct cifsTconInfo *pTcon;
301         char *full_path = NULL;
302         struct inode * newinode = NULL;
303
304         if (!old_valid_dev(device_number))
305                 return -EINVAL;
306
307         xid = GetXid();
308
309         cifs_sb = CIFS_SB(inode->i_sb);
310         pTcon = cifs_sb->tcon;
311
312         down(&direntry->d_sb->s_vfs_rename_sem);
313         full_path = build_path_from_dentry(direntry);
314         up(&direntry->d_sb->s_vfs_rename_sem);
315         if(full_path == NULL)
316                 rc = -ENOMEM;
317         else if (pTcon->ses->capabilities & CAP_UNIX) {
318                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
319                         rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path,
320                                 mode,(__u64)current->euid,(__u64)current->egid,
321                                 device_number, cifs_sb->local_nls,
322                                 cifs_sb->mnt_cifs_flags & 
323                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
324                 } else {
325                         rc = CIFSSMBUnixSetPerms(xid, pTcon,
326                                 full_path, mode, (__u64)-1, (__u64)-1,
327                                 device_number, cifs_sb->local_nls,
328                                 cifs_sb->mnt_cifs_flags & 
329                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
330                 }
331
332                 if(!rc) {
333                         rc = cifs_get_inode_info_unix(&newinode, full_path,
334                                                 inode->i_sb,xid);
335                         if (pTcon->nocase)
336                                 direntry->d_op = &cifs_ci_dentry_ops;
337                         else
338                                 direntry->d_op = &cifs_dentry_ops;
339                         if(rc == 0)
340                                 d_instantiate(direntry, newinode);
341                 }
342         } else {
343                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
344                         int oplock = 0;
345                         u16 fileHandle;
346                         FILE_ALL_INFO * buf;
347
348                         cFYI(1,("sfu compat create special file"));
349
350                         buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL);
351                         if(buf == NULL) {
352                                 kfree(full_path);
353                                 FreeXid(xid);
354                                 return -ENOMEM;
355                         }
356
357                         rc = CIFSSMBOpen(xid, pTcon, full_path,
358                                          FILE_CREATE, /* fail if exists */
359                                          GENERIC_WRITE /* BB would 
360                                           WRITE_OWNER | WRITE_DAC be better? */,
361                                          /* Create a file and set the
362                                             file attribute to SYSTEM */
363                                          CREATE_NOT_DIR | CREATE_OPTION_SPECIAL,
364                                          &fileHandle, &oplock, buf,
365                                          cifs_sb->local_nls,
366                                          cifs_sb->mnt_cifs_flags & 
367                                             CIFS_MOUNT_MAP_SPECIAL_CHR);
368
369                         if(!rc) {
370                                 /* BB Do not bother to decode buf since no
371                                    local inode yet to put timestamps in */
372                                 CIFSSMBClose(xid, pTcon, fileHandle);
373                                 d_drop(direntry);
374                         }
375                         kfree(buf);
376                         /* add code here to set EAs */
377                 }
378         }
379
380         kfree(full_path);
381         FreeXid(xid);
382         return rc;
383 }
384
385
386 struct dentry *
387 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, struct nameidata *nd)
388 {
389         int xid;
390         int rc = 0; /* to get around spurious gcc warning, set to zero here */
391         struct cifs_sb_info *cifs_sb;
392         struct cifsTconInfo *pTcon;
393         struct inode *newInode = NULL;
394         char *full_path = NULL;
395
396         xid = GetXid();
397
398         cFYI(1,
399              (" parent inode = 0x%p name is: %s and dentry = 0x%p",
400               parent_dir_inode, direntry->d_name.name, direntry));
401
402         /* BB Add check of incoming data - e.g. frame not longer than maximum SMB - let server check the namelen BB */
403
404         /* check whether path exists */
405
406         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
407         pTcon = cifs_sb->tcon;
408
409         /* can not grab the rename sem here since it would
410         deadlock in the cases (beginning of sys_rename itself)
411         in which we already have the sb rename sem */
412         full_path = build_path_from_dentry(direntry);
413         if(full_path == NULL) {
414                 FreeXid(xid);
415                 return ERR_PTR(-ENOMEM);
416         }
417
418         if (direntry->d_inode != NULL) {
419                 cFYI(1, (" non-NULL inode in lookup"));
420         } else {
421                 cFYI(1, (" NULL inode in lookup"));
422         }
423         cFYI(1,
424              (" Full path: %s inode = 0x%p", full_path, direntry->d_inode));
425
426         if (pTcon->ses->capabilities & CAP_UNIX)
427                 rc = cifs_get_inode_info_unix(&newInode, full_path,
428                                               parent_dir_inode->i_sb,xid);
429         else
430                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
431                                          parent_dir_inode->i_sb,xid);
432
433         if ((rc == 0) && (newInode != NULL)) {
434                 if (pTcon->nocase)
435                         direntry->d_op = &cifs_ci_dentry_ops;
436                 else
437                         direntry->d_op = &cifs_dentry_ops;
438                 d_add(direntry, newInode);
439
440                 /* since paths are not looked up by component - the parent directories are presumed to be good here */
441                 renew_parental_timestamps(direntry);
442
443         } else if (rc == -ENOENT) {
444                 rc = 0;
445                 d_add(direntry, NULL);
446         } else {
447                 cERROR(1,("Error 0x%x on cifs_get_inode_info in lookup of %s",
448                            rc,full_path));
449                 /* BB special case check for Access Denied - watch security 
450                 exposure of returning dir info implicitly via different rc 
451                 if file exists or not but no access BB */
452         }
453
454         kfree(full_path);
455         FreeXid(xid);
456         return ERR_PTR(rc);
457 }
458
459 static int
460 cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd)
461 {
462         int isValid = 1;
463
464 /*      lock_kernel(); *//* surely we do not want to lock the kernel for a whole network round trip which could take seconds */
465
466         if (direntry->d_inode) {
467                 if (cifs_revalidate(direntry)) {
468                         /* unlock_kernel(); */
469                         return 0;
470                 }
471         } else {
472                 cFYI(1,
473                      ("In cifs_d_revalidate with no inode but name = %s and dentry 0x%p",
474                       direntry->d_name.name, direntry));
475         }
476
477 /*    unlock_kernel(); */
478
479         return isValid;
480 }
481
482 /* static int cifs_d_delete(struct dentry *direntry)
483 {
484         int rc = 0;
485
486         cFYI(1, ("In cifs d_delete, name = %s", direntry->d_name.name));
487
488         return rc;
489 }     */
490
491 struct dentry_operations cifs_dentry_ops = {
492         .d_revalidate = cifs_d_revalidate,
493 /* d_delete:       cifs_d_delete,       *//* not needed except for debugging */
494         /* no need for d_hash, d_compare, d_release, d_iput ... yet. BB confirm this BB */
495 };
496
497 static int cifs_ci_hash(struct dentry *dentry, struct qstr *q)
498 {
499         struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
500         unsigned long hash;
501         int i;
502
503         hash = init_name_hash();
504         for (i = 0; i < q->len; i++)
505                 hash = partial_name_hash(nls_tolower(codepage, q->name[i]),
506                                          hash);
507         q->hash = end_name_hash(hash);
508
509         return 0;
510 }
511
512 static int cifs_ci_compare(struct dentry *dentry, struct qstr *a,
513                            struct qstr *b)
514 {
515         struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
516
517         if ((a->len == b->len) &&
518             (nls_strnicmp(codepage, a->name, b->name, a->len) == 0)) {
519                 /*
520                  * To preserve case, don't let an existing negative dentry's
521                  * case take precedence.  If a is not a negative dentry, this
522                  * should have no side effects
523                  */
524                 memcpy((unsigned char *)a->name, b->name, a->len);
525                 return 0;
526         }
527         return 1;
528 }
529
530 struct dentry_operations cifs_ci_dentry_ops = {
531         .d_revalidate = cifs_d_revalidate,
532         .d_hash = cifs_ci_hash,
533         .d_compare = cifs_ci_compare,
534 };