GNU Linux-libre 4.19.295-gnu1
[releases.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., 2002,2009
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 <linux/mount.h>
28 #include <linux/file.h>
29 #include "cifsfs.h"
30 #include "cifspdu.h"
31 #include "cifsglob.h"
32 #include "cifsproto.h"
33 #include "cifs_debug.h"
34 #include "cifs_fs_sb.h"
35 #include "cifs_unicode.h"
36
37 static void
38 renew_parental_timestamps(struct dentry *direntry)
39 {
40         /* BB check if there is a way to get the kernel to do this or if we
41            really need this */
42         do {
43                 cifs_set_time(direntry, jiffies);
44                 direntry = direntry->d_parent;
45         } while (!IS_ROOT(direntry));
46 }
47
48 char *
49 cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
50                         struct cifs_tcon *tcon, int add_treename)
51 {
52         int pplen = vol->prepath ? strlen(vol->prepath) + 1 : 0;
53         int dfsplen;
54         char *full_path = NULL;
55
56         /* if no prefix path, simply set path to the root of share to "" */
57         if (pplen == 0) {
58                 full_path = kzalloc(1, GFP_KERNEL);
59                 return full_path;
60         }
61
62         if (add_treename)
63                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
64         else
65                 dfsplen = 0;
66
67         full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
68         if (full_path == NULL)
69                 return full_path;
70
71         if (dfsplen)
72                 strncpy(full_path, tcon->treeName, dfsplen);
73         full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
74         strncpy(full_path + dfsplen + 1, vol->prepath, pplen);
75         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
76         full_path[dfsplen + pplen] = 0; /* add trailing null */
77         return full_path;
78 }
79
80 /* Note: caller must free return buffer */
81 char *
82 build_path_from_dentry(struct dentry *direntry)
83 {
84         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
85         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
86         bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
87
88         return build_path_from_dentry_optional_prefix(direntry,
89                                                       prefix);
90 }
91
92 char *
93 build_path_from_dentry_optional_prefix(struct dentry *direntry, bool prefix)
94 {
95         struct dentry *temp;
96         int namelen;
97         int dfsplen;
98         int pplen = 0;
99         char *full_path;
100         char dirsep;
101         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
102         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
103         unsigned seq;
104
105         dirsep = CIFS_DIR_SEP(cifs_sb);
106         if (prefix)
107                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
108         else
109                 dfsplen = 0;
110
111         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
112                 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
113
114 cifs_bp_rename_retry:
115         namelen = dfsplen + pplen;
116         seq = read_seqbegin(&rename_lock);
117         rcu_read_lock();
118         for (temp = direntry; !IS_ROOT(temp);) {
119                 namelen += (1 + temp->d_name.len);
120                 temp = temp->d_parent;
121                 if (temp == NULL) {
122                         cifs_dbg(VFS, "corrupt dentry\n");
123                         rcu_read_unlock();
124                         return NULL;
125                 }
126         }
127         rcu_read_unlock();
128
129         full_path = kmalloc(namelen+1, GFP_KERNEL);
130         if (full_path == NULL)
131                 return full_path;
132         full_path[namelen] = 0; /* trailing null */
133         rcu_read_lock();
134         for (temp = direntry; !IS_ROOT(temp);) {
135                 spin_lock(&temp->d_lock);
136                 namelen -= 1 + temp->d_name.len;
137                 if (namelen < 0) {
138                         spin_unlock(&temp->d_lock);
139                         break;
140                 } else {
141                         full_path[namelen] = dirsep;
142                         strncpy(full_path + namelen + 1, temp->d_name.name,
143                                 temp->d_name.len);
144                         cifs_dbg(FYI, "name: %s\n", full_path + namelen);
145                 }
146                 spin_unlock(&temp->d_lock);
147                 temp = temp->d_parent;
148                 if (temp == NULL) {
149                         cifs_dbg(VFS, "corrupt dentry\n");
150                         rcu_read_unlock();
151                         kfree(full_path);
152                         return NULL;
153                 }
154         }
155         rcu_read_unlock();
156         if (namelen != dfsplen + pplen || read_seqretry(&rename_lock, seq)) {
157                 cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
158                          namelen, dfsplen);
159                 /* presumably this is only possible if racing with a rename
160                 of one of the parent directories  (we can not lock the dentries
161                 above us to prevent this, but retrying should be harmless) */
162                 kfree(full_path);
163                 goto cifs_bp_rename_retry;
164         }
165         /* DIR_SEP already set for byte  0 / vs \ but not for
166            subsequent slashes in prepath which currently must
167            be entered the right way - not sure if there is an alternative
168            since the '\' is a valid posix character so we can not switch
169            those safely to '/' if any are found in the middle of the prepath */
170         /* BB test paths to Windows with '/' in the midst of prepath */
171
172         if (pplen) {
173                 int i;
174
175                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
176                 memcpy(full_path+dfsplen+1, cifs_sb->prepath, pplen-1);
177                 full_path[dfsplen] = dirsep;
178                 for (i = 0; i < pplen-1; i++)
179                         if (full_path[dfsplen+1+i] == '/')
180                                 full_path[dfsplen+1+i] = CIFS_DIR_SEP(cifs_sb);
181         }
182
183         if (dfsplen) {
184                 strncpy(full_path, tcon->treeName, dfsplen);
185                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
186                         int i;
187                         for (i = 0; i < dfsplen; i++) {
188                                 if (full_path[i] == '\\')
189                                         full_path[i] = '/';
190                         }
191                 }
192         }
193         return full_path;
194 }
195
196 /*
197  * Don't allow path components longer than the server max.
198  * Don't allow the separator character in a path component.
199  * The VFS will not allow "/", but "\" is allowed by posix.
200  */
201 static int
202 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
203 {
204         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
205         int i;
206
207         if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
208                      direntry->d_name.len >
209                      le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
210                 return -ENAMETOOLONG;
211
212         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
213                 for (i = 0; i < direntry->d_name.len; i++) {
214                         if (direntry->d_name.name[i] == '\\') {
215                                 cifs_dbg(FYI, "Invalid file name\n");
216                                 return -EINVAL;
217                         }
218                 }
219         }
220         return 0;
221 }
222
223
224 /* Inode operations in similar order to how they appear in Linux file fs.h */
225
226 static int
227 cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
228                struct tcon_link *tlink, unsigned oflags, umode_t mode,
229                __u32 *oplock, struct cifs_fid *fid)
230 {
231         int rc = -ENOENT;
232         int create_options = CREATE_NOT_DIR;
233         int desired_access;
234         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
235         struct cifs_tcon *tcon = tlink_tcon(tlink);
236         char *full_path = NULL;
237         FILE_ALL_INFO *buf = NULL;
238         struct inode *newinode = NULL;
239         int disposition;
240         struct TCP_Server_Info *server = tcon->ses->server;
241         struct cifs_open_parms oparms;
242
243         *oplock = 0;
244         if (tcon->ses->server->oplocks)
245                 *oplock = REQ_OPLOCK;
246
247         full_path = build_path_from_dentry(direntry);
248         if (full_path == NULL) {
249                 rc = -ENOMEM;
250                 goto out;
251         }
252
253         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
254             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
255                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
256                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
257                                      oflags, oplock, &fid->netfid, xid);
258                 switch (rc) {
259                 case 0:
260                         if (newinode == NULL) {
261                                 /* query inode info */
262                                 goto cifs_create_get_file_info;
263                         }
264
265                         if (S_ISDIR(newinode->i_mode)) {
266                                 CIFSSMBClose(xid, tcon, fid->netfid);
267                                 iput(newinode);
268                                 rc = -EISDIR;
269                                 goto out;
270                         }
271
272                         if (!S_ISREG(newinode->i_mode)) {
273                                 /*
274                                  * The server may allow us to open things like
275                                  * FIFOs, but the client isn't set up to deal
276                                  * with that. If it's not a regular file, just
277                                  * close it and proceed as if it were a normal
278                                  * lookup.
279                                  */
280                                 CIFSSMBClose(xid, tcon, fid->netfid);
281                                 goto cifs_create_get_file_info;
282                         }
283                         /* success, no need to query */
284                         goto cifs_create_set_dentry;
285
286                 case -ENOENT:
287                         goto cifs_create_get_file_info;
288
289                 case -EIO:
290                 case -EINVAL:
291                         /*
292                          * EIO could indicate that (posix open) operation is not
293                          * supported, despite what server claimed in capability
294                          * negotiation.
295                          *
296                          * POSIX open in samba versions 3.3.1 and earlier could
297                          * incorrectly fail with invalid parameter.
298                          */
299                         tcon->broken_posix_open = true;
300                         break;
301
302                 case -EREMOTE:
303                 case -EOPNOTSUPP:
304                         /*
305                          * EREMOTE indicates DFS junction, which is not handled
306                          * in posix open.  If either that or op not supported
307                          * returned, follow the normal lookup.
308                          */
309                         break;
310
311                 default:
312                         goto out;
313                 }
314                 /*
315                  * fallthrough to retry, using older open call, this is case
316                  * where server does not support this SMB level, and falsely
317                  * claims capability (also get here for DFS case which should be
318                  * rare for path not covered on files)
319                  */
320         }
321
322         desired_access = 0;
323         if (OPEN_FMODE(oflags) & FMODE_READ)
324                 desired_access |= GENERIC_READ; /* is this too little? */
325         if (OPEN_FMODE(oflags) & FMODE_WRITE)
326                 desired_access |= GENERIC_WRITE;
327
328         disposition = FILE_OVERWRITE_IF;
329         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
330                 disposition = FILE_CREATE;
331         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
332                 disposition = FILE_OVERWRITE_IF;
333         else if ((oflags & O_CREAT) == O_CREAT)
334                 disposition = FILE_OPEN_IF;
335         else
336                 cifs_dbg(FYI, "Create flag not set in create function\n");
337
338         /*
339          * BB add processing to set equivalent of mode - e.g. via CreateX with
340          * ACLs
341          */
342
343         if (!server->ops->open) {
344                 rc = -ENOSYS;
345                 goto out;
346         }
347
348         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
349         if (buf == NULL) {
350                 rc = -ENOMEM;
351                 goto out;
352         }
353
354         /*
355          * if we're not using unix extensions, see if we need to set
356          * ATTR_READONLY on the create call
357          */
358         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
359                 create_options |= CREATE_OPTION_READONLY;
360
361         if (backup_cred(cifs_sb))
362                 create_options |= CREATE_OPEN_BACKUP_INTENT;
363
364         oparms.tcon = tcon;
365         oparms.cifs_sb = cifs_sb;
366         oparms.desired_access = desired_access;
367         oparms.create_options = create_options;
368         oparms.disposition = disposition;
369         oparms.path = full_path;
370         oparms.fid = fid;
371         oparms.reconnect = false;
372         oparms.mode = mode;
373         rc = server->ops->open(xid, &oparms, oplock, buf);
374         if (rc) {
375                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
376                 goto out;
377         }
378
379         /*
380          * If Open reported that we actually created a file then we now have to
381          * set the mode if possible.
382          */
383         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
384                 struct cifs_unix_set_info_args args = {
385                                 .mode   = mode,
386                                 .ctime  = NO_CHANGE_64,
387                                 .atime  = NO_CHANGE_64,
388                                 .mtime  = NO_CHANGE_64,
389                                 .device = 0,
390                 };
391
392                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
393                         args.uid = current_fsuid();
394                         if (inode->i_mode & S_ISGID)
395                                 args.gid = inode->i_gid;
396                         else
397                                 args.gid = current_fsgid();
398                 } else {
399                         args.uid = INVALID_UID; /* no change */
400                         args.gid = INVALID_GID; /* no change */
401                 }
402                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
403                                        current->tgid);
404         } else {
405                 /*
406                  * BB implement mode setting via Windows security
407                  * descriptors e.g.
408                  */
409                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
410
411                 /* Could set r/o dos attribute if mode & 0222 == 0 */
412         }
413
414 cifs_create_get_file_info:
415         /* server might mask mode so we have to query for it */
416         if (tcon->unix_ext)
417                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
418                                               xid);
419         else {
420                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
421                                          xid, fid);
422                 if (newinode) {
423                         if (server->ops->set_lease_key)
424                                 server->ops->set_lease_key(newinode, fid);
425                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
426                                 newinode->i_mode = mode;
427                         if ((*oplock & CIFS_CREATE_ACTION) &&
428                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
429                                 newinode->i_uid = current_fsuid();
430                                 if (inode->i_mode & S_ISGID)
431                                         newinode->i_gid = inode->i_gid;
432                                 else
433                                         newinode->i_gid = current_fsgid();
434                         }
435                 }
436         }
437
438 cifs_create_set_dentry:
439         if (rc != 0) {
440                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
441                          rc);
442                 goto out_err;
443         }
444
445         if (S_ISDIR(newinode->i_mode)) {
446                 rc = -EISDIR;
447                 goto out_err;
448         }
449
450         d_drop(direntry);
451         d_add(direntry, newinode);
452
453 out:
454         kfree(buf);
455         kfree(full_path);
456         return rc;
457
458 out_err:
459         if (server->ops->close)
460                 server->ops->close(xid, tcon, fid);
461         if (newinode)
462                 iput(newinode);
463         goto out;
464 }
465
466 int
467 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
468                  struct file *file, unsigned oflags, umode_t mode)
469 {
470         int rc;
471         unsigned int xid;
472         struct tcon_link *tlink;
473         struct cifs_tcon *tcon;
474         struct TCP_Server_Info *server;
475         struct cifs_fid fid;
476         struct cifs_pending_open open;
477         __u32 oplock;
478         struct cifsFileInfo *file_info;
479
480         /*
481          * Posix open is only called (at lookup time) for file create now. For
482          * opens (rather than creates), because we do not know if it is a file
483          * or directory yet, and current Samba no longer allows us to do posix
484          * open on dirs, we could end up wasting an open call on what turns out
485          * to be a dir. For file opens, we wait to call posix open till
486          * cifs_open.  It could be added to atomic_open in the future but the
487          * performance tradeoff of the extra network request when EISDIR or
488          * EACCES is returned would have to be weighed against the 50% reduction
489          * in network traffic in the other paths.
490          */
491         if (!(oflags & O_CREAT)) {
492                 struct dentry *res;
493
494                 /*
495                  * Check for hashed negative dentry. We have already revalidated
496                  * the dentry and it is fine. No need to perform another lookup.
497                  */
498                 if (!d_in_lookup(direntry))
499                         return -ENOENT;
500
501                 res = cifs_lookup(inode, direntry, 0);
502                 if (IS_ERR(res))
503                         return PTR_ERR(res);
504
505                 return finish_no_open(file, res);
506         }
507
508         xid = get_xid();
509
510         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
511                  inode, direntry, direntry);
512
513         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
514         if (IS_ERR(tlink)) {
515                 rc = PTR_ERR(tlink);
516                 goto out_free_xid;
517         }
518
519         tcon = tlink_tcon(tlink);
520
521         rc = check_name(direntry, tcon);
522         if (rc)
523                 goto out;
524
525         server = tcon->ses->server;
526
527         if (server->ops->new_lease_key)
528                 server->ops->new_lease_key(&fid);
529
530         cifs_add_pending_open(&fid, tlink, &open);
531
532         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
533                             &oplock, &fid);
534
535         if (rc) {
536                 cifs_del_pending_open(&open);
537                 goto out;
538         }
539
540         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
541                 file->f_mode |= FMODE_CREATED;
542
543         rc = finish_open(file, direntry, generic_file_open);
544         if (rc) {
545                 if (server->ops->close)
546                         server->ops->close(xid, tcon, &fid);
547                 cifs_del_pending_open(&open);
548                 goto out;
549         }
550
551         if (file->f_flags & O_DIRECT &&
552             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
553                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
554                         file->f_op = &cifs_file_direct_nobrl_ops;
555                 else
556                         file->f_op = &cifs_file_direct_ops;
557                 }
558
559         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
560         if (file_info == NULL) {
561                 if (server->ops->close)
562                         server->ops->close(xid, tcon, &fid);
563                 cifs_del_pending_open(&open);
564                 rc = -ENOMEM;
565         }
566
567 out:
568         cifs_put_tlink(tlink);
569 out_free_xid:
570         free_xid(xid);
571         return rc;
572 }
573
574 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
575                 bool excl)
576 {
577         int rc;
578         unsigned int xid = get_xid();
579         /*
580          * BB below access is probably too much for mknod to request
581          *    but we have to do query and setpathinfo so requesting
582          *    less could fail (unless we want to request getatr and setatr
583          *    permissions (only).  At least for POSIX we do not have to
584          *    request so much.
585          */
586         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
587         struct tcon_link *tlink;
588         struct cifs_tcon *tcon;
589         struct TCP_Server_Info *server;
590         struct cifs_fid fid;
591         __u32 oplock;
592
593         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
594                  inode, direntry, direntry);
595
596         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
597         rc = PTR_ERR(tlink);
598         if (IS_ERR(tlink))
599                 goto out_free_xid;
600
601         tcon = tlink_tcon(tlink);
602         server = tcon->ses->server;
603
604         if (server->ops->new_lease_key)
605                 server->ops->new_lease_key(&fid);
606
607         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
608                             &oplock, &fid);
609         if (!rc && server->ops->close)
610                 server->ops->close(xid, tcon, &fid);
611
612         cifs_put_tlink(tlink);
613 out_free_xid:
614         free_xid(xid);
615         return rc;
616 }
617
618 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
619                 dev_t device_number)
620 {
621         int rc = -EPERM;
622         unsigned int xid;
623         int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
624         struct cifs_sb_info *cifs_sb;
625         struct tcon_link *tlink;
626         struct cifs_tcon *tcon;
627         struct cifs_io_parms io_parms;
628         char *full_path = NULL;
629         struct inode *newinode = NULL;
630         __u32 oplock = 0;
631         struct cifs_fid fid;
632         struct cifs_open_parms oparms;
633         FILE_ALL_INFO *buf = NULL;
634         unsigned int bytes_written;
635         struct win_dev *pdev;
636         struct kvec iov[2];
637
638         if (!old_valid_dev(device_number))
639                 return -EINVAL;
640
641         cifs_sb = CIFS_SB(inode->i_sb);
642         tlink = cifs_sb_tlink(cifs_sb);
643         if (IS_ERR(tlink))
644                 return PTR_ERR(tlink);
645
646         tcon = tlink_tcon(tlink);
647
648         xid = get_xid();
649
650         full_path = build_path_from_dentry(direntry);
651         if (full_path == NULL) {
652                 rc = -ENOMEM;
653                 goto mknod_out;
654         }
655
656         if (tcon->unix_ext) {
657                 struct cifs_unix_set_info_args args = {
658                         .mode   = mode & ~current_umask(),
659                         .ctime  = NO_CHANGE_64,
660                         .atime  = NO_CHANGE_64,
661                         .mtime  = NO_CHANGE_64,
662                         .device = device_number,
663                 };
664                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
665                         args.uid = current_fsuid();
666                         args.gid = current_fsgid();
667                 } else {
668                         args.uid = INVALID_UID; /* no change */
669                         args.gid = INVALID_GID; /* no change */
670                 }
671                 rc = CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
672                                             cifs_sb->local_nls,
673                                             cifs_remap(cifs_sb));
674                 if (rc)
675                         goto mknod_out;
676
677                 rc = cifs_get_inode_info_unix(&newinode, full_path,
678                                                 inode->i_sb, xid);
679
680                 if (rc == 0)
681                         d_instantiate(direntry, newinode);
682                 goto mknod_out;
683         }
684
685         if (!S_ISCHR(mode) && !S_ISBLK(mode))
686                 goto mknod_out;
687
688         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
689                 goto mknod_out;
690
691
692         cifs_dbg(FYI, "sfu compat create special file\n");
693
694         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
695         if (buf == NULL) {
696                 rc = -ENOMEM;
697                 goto mknod_out;
698         }
699
700         if (backup_cred(cifs_sb))
701                 create_options |= CREATE_OPEN_BACKUP_INTENT;
702
703         oparms.tcon = tcon;
704         oparms.cifs_sb = cifs_sb;
705         oparms.desired_access = GENERIC_WRITE;
706         oparms.create_options = create_options;
707         oparms.disposition = FILE_CREATE;
708         oparms.path = full_path;
709         oparms.fid = &fid;
710         oparms.reconnect = false;
711
712         if (tcon->ses->server->oplocks)
713                 oplock = REQ_OPLOCK;
714         else
715                 oplock = 0;
716         rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, buf);
717         if (rc)
718                 goto mknod_out;
719
720         /*
721          * BB Do not bother to decode buf since no local inode yet to put
722          * timestamps in, but we can reuse it safely.
723          */
724
725         pdev = (struct win_dev *)buf;
726         io_parms.pid = current->tgid;
727         io_parms.tcon = tcon;
728         io_parms.offset = 0;
729         io_parms.length = sizeof(struct win_dev);
730         iov[1].iov_base = buf;
731         iov[1].iov_len = sizeof(struct win_dev);
732         if (S_ISCHR(mode)) {
733                 memcpy(pdev->type, "IntxCHR", 8);
734                 pdev->major = cpu_to_le64(MAJOR(device_number));
735                 pdev->minor = cpu_to_le64(MINOR(device_number));
736                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
737                                                         &bytes_written, iov, 1);
738         } else if (S_ISBLK(mode)) {
739                 memcpy(pdev->type, "IntxBLK", 8);
740                 pdev->major = cpu_to_le64(MAJOR(device_number));
741                 pdev->minor = cpu_to_le64(MINOR(device_number));
742                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
743                                                         &bytes_written, iov, 1);
744         }
745         tcon->ses->server->ops->close(xid, tcon, &fid);
746         d_drop(direntry);
747
748         /* FIXME: add code here to set EAs */
749
750 mknod_out:
751         kfree(full_path);
752         kfree(buf);
753         free_xid(xid);
754         cifs_put_tlink(tlink);
755         return rc;
756 }
757
758 struct dentry *
759 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
760             unsigned int flags)
761 {
762         unsigned int xid;
763         int rc = 0; /* to get around spurious gcc warning, set to zero here */
764         struct cifs_sb_info *cifs_sb;
765         struct tcon_link *tlink;
766         struct cifs_tcon *pTcon;
767         struct inode *newInode = NULL;
768         char *full_path = NULL;
769
770         xid = get_xid();
771
772         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
773                  parent_dir_inode, direntry, direntry);
774
775         /* check whether path exists */
776
777         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
778         tlink = cifs_sb_tlink(cifs_sb);
779         if (IS_ERR(tlink)) {
780                 free_xid(xid);
781                 return ERR_CAST(tlink);
782         }
783         pTcon = tlink_tcon(tlink);
784
785         rc = check_name(direntry, pTcon);
786         if (unlikely(rc)) {
787                 cifs_put_tlink(tlink);
788                 free_xid(xid);
789                 return ERR_PTR(rc);
790         }
791
792         /* can not grab the rename sem here since it would
793         deadlock in the cases (beginning of sys_rename itself)
794         in which we already have the sb rename sem */
795         full_path = build_path_from_dentry(direntry);
796         if (full_path == NULL) {
797                 cifs_put_tlink(tlink);
798                 free_xid(xid);
799                 return ERR_PTR(-ENOMEM);
800         }
801
802         if (d_really_is_positive(direntry)) {
803                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
804         } else {
805                 cifs_dbg(FYI, "NULL inode in lookup\n");
806         }
807         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
808                  full_path, d_inode(direntry));
809
810         if (pTcon->unix_ext) {
811                 rc = cifs_get_inode_info_unix(&newInode, full_path,
812                                               parent_dir_inode->i_sb, xid);
813         } else {
814                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
815                                 parent_dir_inode->i_sb, xid, NULL);
816         }
817
818         if (rc == 0) {
819                 /* since paths are not looked up by component - the parent
820                    directories are presumed to be good here */
821                 renew_parental_timestamps(direntry);
822         } else if (rc == -ENOENT) {
823                 cifs_set_time(direntry, jiffies);
824                 newInode = NULL;
825         } else {
826                 if (rc != -EACCES) {
827                         cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
828                         /* We special case check for Access Denied - since that
829                         is a common return code */
830                 }
831                 newInode = ERR_PTR(rc);
832         }
833         kfree(full_path);
834         cifs_put_tlink(tlink);
835         free_xid(xid);
836         return d_splice_alias(newInode, direntry);
837 }
838
839 static int
840 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
841 {
842         struct inode *inode;
843         int rc;
844
845         if (flags & LOOKUP_RCU)
846                 return -ECHILD;
847
848         if (d_really_is_positive(direntry)) {
849                 inode = d_inode(direntry);
850                 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
851                         CIFS_I(inode)->time = 0; /* force reval */
852
853                 rc = cifs_revalidate_dentry(direntry);
854                 if (rc) {
855                         cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
856                         switch (rc) {
857                         case -ENOENT:
858                         case -ESTALE:
859                                 /*
860                                  * Those errors mean the dentry is invalid
861                                  * (file was deleted or recreated)
862                                  */
863                                 return 0;
864                         default:
865                                 /*
866                                  * Otherwise some unexpected error happened
867                                  * report it as-is to VFS layer
868                                  */
869                                 return rc;
870                         }
871                 }
872                 else {
873                         /*
874                          * If the inode wasn't known to be a dfs entry when
875                          * the dentry was instantiated, such as when created
876                          * via ->readdir(), it needs to be set now since the
877                          * attributes will have been updated by
878                          * cifs_revalidate_dentry().
879                          */
880                         if (IS_AUTOMOUNT(inode) &&
881                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
882                                 spin_lock(&direntry->d_lock);
883                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
884                                 spin_unlock(&direntry->d_lock);
885                         }
886
887                         return 1;
888                 }
889         }
890
891         /*
892          * This may be nfsd (or something), anyway, we can't see the
893          * intent of this. So, since this can be for creation, drop it.
894          */
895         if (!flags)
896                 return 0;
897
898         /*
899          * Drop the negative dentry, in order to make sure to use the
900          * case sensitive name which is specified by user if this is
901          * for creation.
902          */
903         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
904                 return 0;
905
906         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
907                 return 0;
908
909         return 1;
910 }
911
912 /* static int cifs_d_delete(struct dentry *direntry)
913 {
914         int rc = 0;
915
916         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
917
918         return rc;
919 }     */
920
921 const struct dentry_operations cifs_dentry_ops = {
922         .d_revalidate = cifs_d_revalidate,
923         .d_automount = cifs_dfs_d_automount,
924 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
925 };
926
927 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
928 {
929         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
930         unsigned long hash;
931         wchar_t c;
932         int i, charlen;
933
934         hash = init_name_hash(dentry);
935         for (i = 0; i < q->len; i += charlen) {
936                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
937                 /* error out if we can't convert the character */
938                 if (unlikely(charlen < 0))
939                         return charlen;
940                 hash = partial_name_hash(cifs_toupper(c), hash);
941         }
942         q->hash = end_name_hash(hash);
943
944         return 0;
945 }
946
947 static int cifs_ci_compare(const struct dentry *dentry,
948                 unsigned int len, const char *str, const struct qstr *name)
949 {
950         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
951         wchar_t c1, c2;
952         int i, l1, l2;
953
954         /*
955          * We make the assumption here that uppercase characters in the local
956          * codepage are always the same length as their lowercase counterparts.
957          *
958          * If that's ever not the case, then this will fail to match it.
959          */
960         if (name->len != len)
961                 return 1;
962
963         for (i = 0; i < len; i += l1) {
964                 /* Convert characters in both strings to UTF-16. */
965                 l1 = codepage->char2uni(&str[i], len - i, &c1);
966                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
967
968                 /*
969                  * If we can't convert either character, just declare it to
970                  * be 1 byte long and compare the original byte.
971                  */
972                 if (unlikely(l1 < 0 && l2 < 0)) {
973                         if (str[i] != name->name[i])
974                                 return 1;
975                         l1 = 1;
976                         continue;
977                 }
978
979                 /*
980                  * Here, we again ass|u|me that upper/lowercase versions of
981                  * a character are the same length in the local NLS.
982                  */
983                 if (l1 != l2)
984                         return 1;
985
986                 /* Now compare uppercase versions of these characters */
987                 if (cifs_toupper(c1) != cifs_toupper(c2))
988                         return 1;
989         }
990
991         return 0;
992 }
993
994 const struct dentry_operations cifs_ci_dentry_ops = {
995         .d_revalidate = cifs_d_revalidate,
996         .d_hash = cifs_ci_hash,
997         .d_compare = cifs_ci_compare,
998         .d_automount = cifs_dfs_d_automount,
999 };