[CIFS] Convert remaining places in fs/cifs from
[sfrench/cifs-2.6.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 = 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->fsuid,
204                                         (__u64)current->fsgid,
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                                 if((oplock & CIFS_CREATE_ACTION) &&
234                                   (cifs_sb->mnt_cifs_flags & 
235                                      CIFS_MOUNT_SET_UID)) {
236                                         newinode->i_uid = current->fsuid;
237                                         newinode->i_gid = current->fsgid;
238                                 }
239                         }
240                 }
241
242                 if (rc != 0) {
243                         cFYI(1,
244                              ("Create worked but get_inode_info failed rc = %d",
245                               rc));
246                 } else {
247                         if (pTcon->nocase)
248                                 direntry->d_op = &cifs_ci_dentry_ops;
249                         else
250                                 direntry->d_op = &cifs_dentry_ops;
251                         d_instantiate(direntry, newinode);
252                 }
253                 if((nd->flags & LOOKUP_OPEN) == FALSE) {
254                         /* mknod case - do not leave file open */
255                         CIFSSMBClose(xid, pTcon, fileHandle);
256                 } else if(newinode) {
257                         pCifsFile =
258                            kzalloc(sizeof (struct cifsFileInfo), GFP_KERNEL);
259                         
260                         if(pCifsFile == NULL)
261                                 goto cifs_create_out;
262                         pCifsFile->netfid = fileHandle;
263                         pCifsFile->pid = current->tgid;
264                         pCifsFile->pInode = newinode;
265                         pCifsFile->invalidHandle = FALSE;
266                         pCifsFile->closePend     = FALSE;
267                         init_MUTEX(&pCifsFile->fh_sem);
268                         /* set the following in open now 
269                                 pCifsFile->pfile = file; */
270                         write_lock(&GlobalSMBSeslock);
271                         list_add(&pCifsFile->tlist,&pTcon->openFileList);
272                         pCifsInode = CIFS_I(newinode);
273                         if(pCifsInode) {
274                                 /* if readable file instance put first in list*/
275                                 if (write_only == TRUE) {
276                                         list_add_tail(&pCifsFile->flist,
277                                                 &pCifsInode->openFileList);
278                                 } else {
279                                         list_add(&pCifsFile->flist,
280                                                 &pCifsInode->openFileList);
281                                 }
282                                 if((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
283                                         pCifsInode->clientCanCacheAll = TRUE;
284                                         pCifsInode->clientCanCacheRead = TRUE;
285                                         cFYI(1,("Exclusive Oplock for inode %p",
286                                                 newinode));
287                                 } else if((oplock & 0xF) == OPLOCK_READ)
288                                         pCifsInode->clientCanCacheRead = TRUE;
289                         }
290                         write_unlock(&GlobalSMBSeslock);
291                 }
292         } 
293 cifs_create_out:
294         kfree(buf);
295         kfree(full_path);
296         FreeXid(xid);
297         return rc;
298 }
299
300 int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, 
301                 dev_t device_number) 
302 {
303         int rc = -EPERM;
304         int xid;
305         struct cifs_sb_info *cifs_sb;
306         struct cifsTconInfo *pTcon;
307         char *full_path = NULL;
308         struct inode * newinode = NULL;
309
310         if (!old_valid_dev(device_number))
311                 return -EINVAL;
312
313         xid = GetXid();
314
315         cifs_sb = CIFS_SB(inode->i_sb);
316         pTcon = cifs_sb->tcon;
317
318         down(&direntry->d_sb->s_vfs_rename_sem);
319         full_path = build_path_from_dentry(direntry);
320         up(&direntry->d_sb->s_vfs_rename_sem);
321         if(full_path == NULL)
322                 rc = -ENOMEM;
323         else if (pTcon->ses->capabilities & CAP_UNIX) {
324                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
325                         rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path,
326                                 mode,(__u64)current->fsuid,(__u64)current->fsgid,
327                                 device_number, cifs_sb->local_nls,
328                                 cifs_sb->mnt_cifs_flags & 
329                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
330                 } else {
331                         rc = CIFSSMBUnixSetPerms(xid, pTcon,
332                                 full_path, mode, (__u64)-1, (__u64)-1,
333                                 device_number, cifs_sb->local_nls,
334                                 cifs_sb->mnt_cifs_flags & 
335                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
336                 }
337
338                 if(!rc) {
339                         rc = cifs_get_inode_info_unix(&newinode, full_path,
340                                                 inode->i_sb,xid);
341                         if (pTcon->nocase)
342                                 direntry->d_op = &cifs_ci_dentry_ops;
343                         else
344                                 direntry->d_op = &cifs_dentry_ops;
345                         if(rc == 0)
346                                 d_instantiate(direntry, newinode);
347                 }
348         } else {
349                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
350                         int oplock = 0;
351                         u16 fileHandle;
352                         FILE_ALL_INFO * buf;
353
354                         cFYI(1,("sfu compat create special file"));
355
356                         buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL);
357                         if(buf == NULL) {
358                                 kfree(full_path);
359                                 FreeXid(xid);
360                                 return -ENOMEM;
361                         }
362
363                         rc = CIFSSMBOpen(xid, pTcon, full_path,
364                                          FILE_CREATE, /* fail if exists */
365                                          GENERIC_WRITE /* BB would 
366                                           WRITE_OWNER | WRITE_DAC be better? */,
367                                          /* Create a file and set the
368                                             file attribute to SYSTEM */
369                                          CREATE_NOT_DIR | CREATE_OPTION_SPECIAL,
370                                          &fileHandle, &oplock, buf,
371                                          cifs_sb->local_nls,
372                                          cifs_sb->mnt_cifs_flags & 
373                                             CIFS_MOUNT_MAP_SPECIAL_CHR);
374
375                         if(!rc) {
376                                 /* BB Do not bother to decode buf since no
377                                    local inode yet to put timestamps in,
378                                    but we can reuse it safely */
379                                 int bytes_written;
380                                 struct win_dev *pdev;
381                                 pdev = (struct win_dev *)buf;
382                                 if(S_ISCHR(mode)) {
383                                         memcpy(pdev->type, "IntxCHR", 8);
384                                         pdev->major =
385                                               cpu_to_le64(MAJOR(device_number));
386                                         pdev->minor = 
387                                               cpu_to_le64(MINOR(device_number));
388                                         rc = CIFSSMBWrite(xid, pTcon,
389                                                 fileHandle,
390                                                 sizeof(struct win_dev),
391                                                 0, &bytes_written, (char *)pdev,
392                                                 NULL, 0);
393                                 } else if(S_ISBLK(mode)) {
394                                         memcpy(pdev->type, "IntxBLK", 8);
395                                         pdev->major =
396                                               cpu_to_le64(MAJOR(device_number));
397                                         pdev->minor =
398                                               cpu_to_le64(MINOR(device_number));
399                                         rc = CIFSSMBWrite(xid, pTcon,
400                                                 fileHandle,
401                                                 sizeof(struct win_dev),
402                                                 0, &bytes_written, (char *)pdev,
403                                                 NULL, 0);
404                                 } /* else if(S_ISFIFO */
405                                 CIFSSMBClose(xid, pTcon, fileHandle);
406                                 d_drop(direntry);
407                         }
408                         kfree(buf);
409                         /* add code here to set EAs */
410                 }
411         }
412
413         kfree(full_path);
414         FreeXid(xid);
415         return rc;
416 }
417
418
419 struct dentry *
420 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, struct nameidata *nd)
421 {
422         int xid;
423         int rc = 0; /* to get around spurious gcc warning, set to zero here */
424         struct cifs_sb_info *cifs_sb;
425         struct cifsTconInfo *pTcon;
426         struct inode *newInode = NULL;
427         char *full_path = NULL;
428
429         xid = GetXid();
430
431         cFYI(1,
432              (" parent inode = 0x%p name is: %s and dentry = 0x%p",
433               parent_dir_inode, direntry->d_name.name, direntry));
434
435         /* BB Add check of incoming data - e.g. frame not longer than maximum SMB - let server check the namelen BB */
436
437         /* check whether path exists */
438
439         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
440         pTcon = cifs_sb->tcon;
441
442         /* can not grab the rename sem here since it would
443         deadlock in the cases (beginning of sys_rename itself)
444         in which we already have the sb rename sem */
445         full_path = build_path_from_dentry(direntry);
446         if(full_path == NULL) {
447                 FreeXid(xid);
448                 return ERR_PTR(-ENOMEM);
449         }
450
451         if (direntry->d_inode != NULL) {
452                 cFYI(1, (" non-NULL inode in lookup"));
453         } else {
454                 cFYI(1, (" NULL inode in lookup"));
455         }
456         cFYI(1,
457              (" Full path: %s inode = 0x%p", full_path, direntry->d_inode));
458
459         if (pTcon->ses->capabilities & CAP_UNIX)
460                 rc = cifs_get_inode_info_unix(&newInode, full_path,
461                                               parent_dir_inode->i_sb,xid);
462         else
463                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
464                                          parent_dir_inode->i_sb,xid);
465
466         if ((rc == 0) && (newInode != NULL)) {
467                 if (pTcon->nocase)
468                         direntry->d_op = &cifs_ci_dentry_ops;
469                 else
470                         direntry->d_op = &cifs_dentry_ops;
471                 d_add(direntry, newInode);
472
473                 /* since paths are not looked up by component - the parent 
474                    directories are presumed to be good here */
475                 renew_parental_timestamps(direntry);
476
477         } else if (rc == -ENOENT) {
478                 rc = 0;
479                 direntry->d_time = jiffies;
480                 if (pTcon->nocase)
481                         direntry->d_op = &cifs_ci_dentry_ops;
482                 else
483                         direntry->d_op = &cifs_dentry_ops;
484                 d_add(direntry, NULL);
485         /*      if it was once a directory (but how can we tell?) we could do  
486                         shrink_dcache_parent(direntry); */
487         } else {
488                 cERROR(1,("Error 0x%x on cifs_get_inode_info in lookup of %s",
489                            rc,full_path));
490                 /* BB special case check for Access Denied - watch security 
491                 exposure of returning dir info implicitly via different rc 
492                 if file exists or not but no access BB */
493         }
494
495         kfree(full_path);
496         FreeXid(xid);
497         return ERR_PTR(rc);
498 }
499
500 static int
501 cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd)
502 {
503         int isValid = 1;
504
505         if (direntry->d_inode) {
506                 if (cifs_revalidate(direntry)) {
507                         return 0;
508                 }
509         } else {
510                 cFYI(1, ("neg dentry 0x%p name = %s",
511                          direntry, direntry->d_name.name));
512                 if(time_after(jiffies, direntry->d_time + HZ) || 
513                         !lookupCacheEnabled) {
514                         d_drop(direntry);
515                         isValid = 0;
516                 } 
517         }
518
519         return isValid;
520 }
521
522 /* static int cifs_d_delete(struct dentry *direntry)
523 {
524         int rc = 0;
525
526         cFYI(1, ("In cifs d_delete, name = %s", direntry->d_name.name));
527
528         return rc;
529 }     */
530
531 struct dentry_operations cifs_dentry_ops = {
532         .d_revalidate = cifs_d_revalidate,
533 /* d_delete:       cifs_d_delete,       *//* not needed except for debugging */
534         /* no need for d_hash, d_compare, d_release, d_iput ... yet. BB confirm this BB */
535 };
536
537 static int cifs_ci_hash(struct dentry *dentry, struct qstr *q)
538 {
539         struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
540         unsigned long hash;
541         int i;
542
543         hash = init_name_hash();
544         for (i = 0; i < q->len; i++)
545                 hash = partial_name_hash(nls_tolower(codepage, q->name[i]),
546                                          hash);
547         q->hash = end_name_hash(hash);
548
549         return 0;
550 }
551
552 static int cifs_ci_compare(struct dentry *dentry, struct qstr *a,
553                            struct qstr *b)
554 {
555         struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls;
556
557         if ((a->len == b->len) &&
558             (nls_strnicmp(codepage, a->name, b->name, a->len) == 0)) {
559                 /*
560                  * To preserve case, don't let an existing negative dentry's
561                  * case take precedence.  If a is not a negative dentry, this
562                  * should have no side effects
563                  */
564                 memcpy((unsigned char *)a->name, b->name, a->len);
565                 return 0;
566         }
567         return 1;
568 }
569
570 struct dentry_operations cifs_ci_dentry_ops = {
571         .d_revalidate = cifs_d_revalidate,
572         .d_hash = cifs_ci_hash,
573         .d_compare = cifs_ci_compare,
574 };