Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
[pandora-kernel.git] / 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., 2002,2005
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;
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         dirsep = CIFS_DIR_SEP(CIFS_SB(direntry->d_sb));
59 cifs_bp_rename_retry:
60         for (temp = direntry; !IS_ROOT(temp);) {
61                 namelen += (1 + temp->d_name.len);
62                 temp = temp->d_parent;
63                 if(temp == NULL) {
64                         cERROR(1,("corrupt dentry"));
65                         return NULL;
66                 }
67         }
68
69         full_path = kmalloc(namelen+1, GFP_KERNEL);
70         if(full_path == NULL)
71                 return full_path;
72         full_path[namelen] = 0; /* trailing null */
73
74         for (temp = direntry; !IS_ROOT(temp);) {
75                 namelen -= 1 + temp->d_name.len;
76                 if (namelen < 0) {
77                         break;
78                 } else {
79                         full_path[namelen] = dirsep;
80                         strncpy(full_path + namelen + 1, temp->d_name.name,
81                                 temp->d_name.len);
82                         cFYI(0, (" name: %s ", full_path + namelen));
83                 }
84                 temp = temp->d_parent;
85                 if(temp == NULL) {
86                         cERROR(1,("corrupt dentry"));
87                         kfree(full_path);
88                         return NULL;
89                 }
90         }
91         if (namelen != 0) {
92                 cERROR(1,
93                        ("We did not end path lookup where we expected namelen is %d",
94                         namelen));
95                 /* presumably this is only possible if we were racing with a rename 
96                 of one of the parent directories  (we can not lock the dentries
97                 above us to prevent this, but retrying should be harmless) */
98                 kfree(full_path);
99                 namelen = 0;
100                 goto cifs_bp_rename_retry;
101         }
102
103         return full_path;
104 }
105
106 /* char * build_wildcard_path_from_dentry(struct dentry *direntry)
107 {
108         if(full_path == NULL)
109                 return full_path;
110
111         full_path[namelen] = '\\';
112         full_path[namelen+1] = '*';
113         full_path[namelen+2] = 0;
114 BB remove above eight lines BB */
115
116 /* Inode operations in similar order to how they appear in Linux file fs.h */
117
118 int
119 cifs_create(struct inode *inode, struct dentry *direntry, int mode,
120                 struct nameidata *nd)
121 {
122         int rc = -ENOENT;
123         int xid;
124         int oplock = 0;
125         int desiredAccess = GENERIC_READ | GENERIC_WRITE;
126         __u16 fileHandle;
127         struct cifs_sb_info *cifs_sb;
128         struct cifsTconInfo *pTcon;
129         char *full_path = NULL;
130         FILE_ALL_INFO * buf = NULL;
131         struct inode *newinode = NULL;
132         struct cifsFileInfo * pCifsFile = NULL;
133         struct cifsInodeInfo * pCifsInode;
134         int disposition = FILE_OVERWRITE_IF;
135         int write_only = FALSE;
136
137         xid = GetXid();
138
139         cifs_sb = CIFS_SB(inode->i_sb);
140         pTcon = cifs_sb->tcon;
141
142         full_path = build_path_from_dentry(direntry);
143         if(full_path == NULL) {
144                 FreeXid(xid);
145                 return -ENOMEM;
146         }
147
148         if(nd && (nd->flags & LOOKUP_OPEN)) {
149                 int oflags = nd->intent.open.flags;
150
151                 desiredAccess = 0;
152                 if (oflags & FMODE_READ)
153                         desiredAccess |= GENERIC_READ;
154                 if (oflags & FMODE_WRITE) {
155                         desiredAccess |= GENERIC_WRITE;
156                         if (!(oflags & FMODE_READ))
157                                 write_only = TRUE;
158                 }
159
160                 if((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
161                         disposition = FILE_CREATE;
162                 else if((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
163                         disposition = FILE_OVERWRITE_IF;
164                 else if((oflags & O_CREAT) == O_CREAT)
165                         disposition = FILE_OPEN_IF;
166                 else {
167                         cFYI(1,("Create flag not set in create function"));
168                 }
169         }
170
171         /* BB add processing to set equivalent of mode - e.g. via CreateX with ACLs */
172         if (oplockEnabled)
173                 oplock = REQ_OPLOCK;
174
175         buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL);
176         if(buf == NULL) {
177                 kfree(full_path);
178                 FreeXid(xid);
179                 return -ENOMEM;
180         }
181         if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS) 
182                 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition,
183                          desiredAccess, CREATE_NOT_DIR,
184                          &fileHandle, &oplock, buf, cifs_sb->local_nls,
185                          cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
186         else
187                 rc = -EIO; /* no NT SMB support fall into legacy open below */
188
189         if(rc == -EIO) {
190                 /* old server, retry the open legacy style */
191                 rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
192                         desiredAccess, CREATE_NOT_DIR,
193                         &fileHandle, &oplock, buf, cifs_sb->local_nls,
194                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
195         } 
196         if (rc) {
197                 cFYI(1, ("cifs_create returned 0x%x", rc));
198         } else {
199                 /* If Open reported that we actually created a file
200                 then we now have to set the mode if possible */
201                 if ((cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
202                         (oplock & CIFS_CREATE_ACTION))
203                         if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
204                                 CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
205                                         (__u64)current->fsuid,
206                                         (__u64)current->fsgid,
207                                         0 /* dev */,
208                                         cifs_sb->local_nls, 
209                                         cifs_sb->mnt_cifs_flags & 
210                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
211                         } else {
212                                 CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,
213                                         (__u64)-1,
214                                         (__u64)-1,
215                                         0 /* dev */,
216                                         cifs_sb->local_nls,
217                                         cifs_sb->mnt_cifs_flags & 
218                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
219                         }
220                 else {
221                         /* BB implement mode setting via Windows security descriptors */
222                         /* eg CIFSSMBWinSetPerms(xid,pTcon,full_path,mode,-1,-1,local_nls);*/
223                         /* could set r/o dos attribute if mode & 0222 == 0 */
224                 }
225
226         /* BB server might mask mode so we have to query for Unix case*/
227                 if (pTcon->ses->capabilities & CAP_UNIX)
228                         rc = cifs_get_inode_info_unix(&newinode, full_path,
229                                                  inode->i_sb,xid);
230                 else {
231                         rc = cifs_get_inode_info(&newinode, full_path,
232                                                  buf, inode->i_sb,xid);
233                         if(newinode) {
234                                 newinode->i_mode = mode;
235                                 if((oplock & CIFS_CREATE_ACTION) &&
236                                   (cifs_sb->mnt_cifs_flags & 
237                                      CIFS_MOUNT_SET_UID)) {
238                                         newinode->i_uid = current->fsuid;
239                                         newinode->i_gid = current->fsgid;
240                                 }
241                         }
242                 }
243
244                 if (rc != 0) {
245                         cFYI(1,
246                              ("Create worked but get_inode_info failed rc = %d",
247                               rc));
248                 } else {
249                         if (pTcon->nocase)
250                                 direntry->d_op = &cifs_ci_dentry_ops;
251                         else
252                                 direntry->d_op = &cifs_dentry_ops;
253                         d_instantiate(direntry, newinode);
254                 }
255                 if((nd->flags & LOOKUP_OPEN) == FALSE) {
256                         /* mknod case - do not leave file open */
257                         CIFSSMBClose(xid, pTcon, fileHandle);
258                 } else if(newinode) {
259                         pCifsFile =
260                            kzalloc(sizeof (struct cifsFileInfo), GFP_KERNEL);
261                         
262                         if(pCifsFile == NULL)
263                                 goto cifs_create_out;
264                         pCifsFile->netfid = fileHandle;
265                         pCifsFile->pid = current->tgid;
266                         pCifsFile->pInode = newinode;
267                         pCifsFile->invalidHandle = FALSE;
268                         pCifsFile->closePend     = FALSE;
269                         init_MUTEX(&pCifsFile->fh_sem);
270                         init_MUTEX(&pCifsFile->lock_sem);
271                         INIT_LIST_HEAD(&pCifsFile->llist);
272                         atomic_set(&pCifsFile->wrtPending,0);
273
274                         /* set the following in open now 
275                                 pCifsFile->pfile = file; */
276                         write_lock(&GlobalSMBSeslock);
277                         list_add(&pCifsFile->tlist,&pTcon->openFileList);
278                         pCifsInode = CIFS_I(newinode);
279                         if(pCifsInode) {
280                                 /* if readable file instance put first in list*/
281                                 if (write_only == TRUE) {
282                                         list_add_tail(&pCifsFile->flist,
283                                                 &pCifsInode->openFileList);
284                                 } else {
285                                         list_add(&pCifsFile->flist,
286                                                 &pCifsInode->openFileList);
287                                 }
288                                 if((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
289                                         pCifsInode->clientCanCacheAll = TRUE;
290                                         pCifsInode->clientCanCacheRead = TRUE;
291                                         cFYI(1,("Exclusive Oplock for inode %p",
292                                                 newinode));
293                                 } else if((oplock & 0xF) == OPLOCK_READ)
294                                         pCifsInode->clientCanCacheRead = TRUE;
295                         }
296                         write_unlock(&GlobalSMBSeslock);
297                 }
298         } 
299 cifs_create_out:
300         kfree(buf);
301         kfree(full_path);
302         FreeXid(xid);
303         return rc;
304 }
305
306 int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, 
307                 dev_t device_number) 
308 {
309         int rc = -EPERM;
310         int xid;
311         struct cifs_sb_info *cifs_sb;
312         struct cifsTconInfo *pTcon;
313         char *full_path = NULL;
314         struct inode * newinode = NULL;
315
316         if (!old_valid_dev(device_number))
317                 return -EINVAL;
318
319         xid = GetXid();
320
321         cifs_sb = CIFS_SB(inode->i_sb);
322         pTcon = cifs_sb->tcon;
323
324         full_path = build_path_from_dentry(direntry);
325         if(full_path == NULL)
326                 rc = -ENOMEM;
327         else if (pTcon->ses->capabilities & CAP_UNIX) {
328                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
329                         rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path,
330                                 mode,(__u64)current->fsuid,(__u64)current->fsgid,
331                                 device_number, cifs_sb->local_nls,
332                                 cifs_sb->mnt_cifs_flags & 
333                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
334                 } else {
335                         rc = CIFSSMBUnixSetPerms(xid, pTcon,
336                                 full_path, mode, (__u64)-1, (__u64)-1,
337                                 device_number, cifs_sb->local_nls,
338                                 cifs_sb->mnt_cifs_flags & 
339                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
340                 }
341
342                 if(!rc) {
343                         rc = cifs_get_inode_info_unix(&newinode, full_path,
344                                                 inode->i_sb,xid);
345                         if (pTcon->nocase)
346                                 direntry->d_op = &cifs_ci_dentry_ops;
347                         else
348                                 direntry->d_op = &cifs_dentry_ops;
349                         if(rc == 0)
350                                 d_instantiate(direntry, newinode);
351                 }
352         } else {
353                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
354                         int oplock = 0;
355                         u16 fileHandle;
356                         FILE_ALL_INFO * buf;
357
358                         cFYI(1,("sfu compat create special file"));
359
360                         buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL);
361                         if(buf == NULL) {
362                                 kfree(full_path);
363                                 FreeXid(xid);
364                                 return -ENOMEM;
365                         }
366
367                         rc = CIFSSMBOpen(xid, pTcon, full_path,
368                                          FILE_CREATE, /* fail if exists */
369                                          GENERIC_WRITE /* BB would 
370                                           WRITE_OWNER | WRITE_DAC be better? */,
371                                          /* Create a file and set the
372                                             file attribute to SYSTEM */
373                                          CREATE_NOT_DIR | CREATE_OPTION_SPECIAL,
374                                          &fileHandle, &oplock, buf,
375                                          cifs_sb->local_nls,
376                                          cifs_sb->mnt_cifs_flags & 
377                                             CIFS_MOUNT_MAP_SPECIAL_CHR);
378
379                         /* BB FIXME - add handling for backlevel servers
380                            which need legacy open and check for all
381                            calls to SMBOpen for fallback to 
382                            SMBLeagcyOpen */
383                         if(!rc) {
384                                 /* BB Do not bother to decode buf since no
385                                    local inode yet to put timestamps in,
386                                    but we can reuse it safely */
387                                 int bytes_written;
388                                 struct win_dev *pdev;
389                                 pdev = (struct win_dev *)buf;
390                                 if(S_ISCHR(mode)) {
391                                         memcpy(pdev->type, "IntxCHR", 8);
392                                         pdev->major =
393                                               cpu_to_le64(MAJOR(device_number));
394                                         pdev->minor = 
395                                               cpu_to_le64(MINOR(device_number));
396                                         rc = CIFSSMBWrite(xid, pTcon,
397                                                 fileHandle,
398                                                 sizeof(struct win_dev),
399                                                 0, &bytes_written, (char *)pdev,
400                                                 NULL, 0);
401                                 } else if(S_ISBLK(mode)) {
402                                         memcpy(pdev->type, "IntxBLK", 8);
403                                         pdev->major =
404                                               cpu_to_le64(MAJOR(device_number));
405                                         pdev->minor =
406                                               cpu_to_le64(MINOR(device_number));
407                                         rc = CIFSSMBWrite(xid, pTcon,
408                                                 fileHandle,
409                                                 sizeof(struct win_dev),
410                                                 0, &bytes_written, (char *)pdev,
411                                                 NULL, 0);
412                                 } /* else if(S_ISFIFO */
413                                 CIFSSMBClose(xid, pTcon, fileHandle);
414                                 d_drop(direntry);
415                         }
416                         kfree(buf);
417                         /* add code here to set EAs */
418                 }
419         }
420
421         kfree(full_path);
422         FreeXid(xid);
423         return rc;
424 }
425
426
427 struct dentry *
428 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, struct nameidata *nd)
429 {
430         int xid;
431         int rc = 0; /* to get around spurious gcc warning, set to zero here */
432         struct cifs_sb_info *cifs_sb;
433         struct cifsTconInfo *pTcon;
434         struct inode *newInode = NULL;
435         char *full_path = NULL;
436
437         xid = GetXid();
438
439         cFYI(1,
440              (" parent inode = 0x%p name is: %s and dentry = 0x%p",
441               parent_dir_inode, direntry->d_name.name, direntry));
442
443         /* BB Add check of incoming data - e.g. frame not longer than maximum SMB - let server check the namelen BB */
444
445         /* check whether path exists */
446
447         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
448         pTcon = cifs_sb->tcon;
449
450         /*
451          * Don't allow the separator character in a path component.
452          * The VFS will not allow "/", but "\" is allowed by posix.
453          */
454         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
455                 int i;
456                 for (i = 0; i < direntry->d_name.len; i++)
457                         if (direntry->d_name.name[i] == '\\') {
458                                 cFYI(1, ("Invalid file name"));
459                                 FreeXid(xid);
460                                 return ERR_PTR(-EINVAL);
461                         }
462         }
463
464         /* can not grab the rename sem here since it would
465         deadlock in the cases (beginning of sys_rename itself)
466         in which we already have the sb rename sem */
467         full_path = build_path_from_dentry(direntry);
468         if(full_path == NULL) {
469                 FreeXid(xid);
470                 return ERR_PTR(-ENOMEM);
471         }
472
473         if (direntry->d_inode != NULL) {
474                 cFYI(1, (" non-NULL inode in lookup"));
475         } else {
476                 cFYI(1, (" NULL inode in lookup"));
477         }
478         cFYI(1,
479              (" Full path: %s inode = 0x%p", full_path, direntry->d_inode));
480
481         if (pTcon->ses->capabilities & CAP_UNIX)
482                 rc = cifs_get_inode_info_unix(&newInode, full_path,
483                                               parent_dir_inode->i_sb,xid);
484         else
485                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
486                                          parent_dir_inode->i_sb,xid);
487
488         if ((rc == 0) && (newInode != NULL)) {
489                 if (pTcon->nocase)
490                         direntry->d_op = &cifs_ci_dentry_ops;
491                 else
492                         direntry->d_op = &cifs_dentry_ops;
493                 d_add(direntry, newInode);
494
495                 /* since paths are not looked up by component - the parent 
496                    directories are presumed to be good here */
497                 renew_parental_timestamps(direntry);
498
499         } else if (rc == -ENOENT) {
500                 rc = 0;
501                 direntry->d_time = jiffies;
502                 if (pTcon->nocase)
503                         direntry->d_op = &cifs_ci_dentry_ops;
504                 else
505                         direntry->d_op = &cifs_dentry_ops;
506                 d_add(direntry, NULL);
507         /*      if it was once a directory (but how can we tell?) we could do  
508                         shrink_dcache_parent(direntry); */
509         } else {
510                 cERROR(1,("Error 0x%x on cifs_get_inode_info in lookup of %s",
511                            rc,full_path));
512                 /* BB special case check for Access Denied - watch security 
513                 exposure of returning dir info implicitly via different rc 
514                 if file exists or not but no access BB */
515         }
516
517         kfree(full_path);
518         FreeXid(xid);
519         return ERR_PTR(rc);
520 }
521
522 static int
523 cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd)
524 {
525         int isValid = 1;
526
527         if (direntry->d_inode) {
528                 if (cifs_revalidate(direntry)) {
529                         return 0;
530                 }
531         } else {
532                 cFYI(1, ("neg dentry 0x%p name = %s",
533                          direntry, direntry->d_name.name));
534                 if(time_after(jiffies, direntry->d_time + HZ) || 
535                         !lookupCacheEnabled) {
536                         d_drop(direntry);
537                         isValid = 0;
538                 } 
539         }
540
541         return isValid;
542 }
543
544 /* static int cifs_d_delete(struct dentry *direntry)
545 {
546         int rc = 0;
547
548         cFYI(1, ("In cifs d_delete, name = %s", direntry->d_name.name));
549
550         return rc;
551 }     */
552
553 struct dentry_operations cifs_dentry_ops = {
554         .d_revalidate = cifs_d_revalidate,
555 /* d_delete:       cifs_d_delete,       *//* not needed except for debugging */
556         /* no need for d_hash, d_compare, d_release, d_iput ... yet. BB confirm this BB */
557 };
558
559 static int cifs_ci_hash(struct dentry *dentry, struct qstr *q)
560 {
561         struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
562         unsigned long hash;
563         int i;
564
565         hash = init_name_hash();
566         for (i = 0; i < q->len; i++)
567                 hash = partial_name_hash(nls_tolower(codepage, q->name[i]),
568                                          hash);
569         q->hash = end_name_hash(hash);
570
571         return 0;
572 }
573
574 static int cifs_ci_compare(struct dentry *dentry, struct qstr *a,
575                            struct qstr *b)
576 {
577         struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
578
579         if ((a->len == b->len) &&
580             (nls_strnicmp(codepage, a->name, b->name, a->len) == 0)) {
581                 /*
582                  * To preserve case, don't let an existing negative dentry's
583                  * case take precedence.  If a is not a negative dentry, this
584                  * should have no side effects
585                  */
586                 memcpy((unsigned char *)a->name, b->name, a->len);
587                 return 0;
588         }
589         return 1;
590 }
591
592 struct dentry_operations cifs_ci_dentry_ops = {
593         .d_revalidate = cifs_d_revalidate,
594         .d_hash = cifs_ci_hash,
595         .d_compare = cifs_ci_compare,
596 };