6b36c43d38f540593c8c09090d8ef7fb7b56c41b
[linux-2.6.git] / fs / cifs / readdir.c
1 /*
2  *   fs/cifs/readdir.c
3  *
4  *   Directory search handling
5  * 
6  *   Copyright (C) International Business Machines  Corp., 2004, 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/smp_lock.h>
26 #include "cifspdu.h"
27 #include "cifsglob.h"
28 #include "cifsproto.h"
29 #include "cifs_unicode.h"
30 #include "cifs_debug.h"
31 #include "cifs_fs_sb.h"
32 #include "cifsfs.h"
33
34 /* BB fixme - add debug wrappers around this function to disable it fixme BB */
35 /* static void dump_cifs_file_struct(struct file *file, char *label)
36 {
37         struct cifsFileInfo * cf;
38
39         if(file) {
40                 cf = file->private_data;
41                 if(cf == NULL) {
42                         cFYI(1,("empty cifs private file data"));
43                         return;
44                 }
45                 if(cf->invalidHandle) {
46                         cFYI(1,("invalid handle"));
47                 }
48                 if(cf->srch_inf.endOfSearch) {
49                         cFYI(1,("end of search"));
50                 }
51                 if(cf->srch_inf.emptyDir) {
52                         cFYI(1,("empty dir"));
53                 }
54                 
55         }
56 } */
57
58 /* Returns one if new inode created (which therefore needs to be hashed) */
59 /* Might check in the future if inode number changed so we can rehash inode */
60 static int construct_dentry(struct qstr *qstring, struct file *file,
61         struct inode **ptmp_inode, struct dentry **pnew_dentry)
62 {
63         struct dentry *tmp_dentry;
64         struct cifs_sb_info *cifs_sb;
65         struct cifsTconInfo *pTcon;
66         int rc = 0;
67
68         cFYI(1, ("For %s", qstring->name));
69         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
70         pTcon = cifs_sb->tcon;
71
72         qstring->hash = full_name_hash(qstring->name, qstring->len);
73         tmp_dentry = d_lookup(file->f_dentry, qstring);
74         if (tmp_dentry) {
75                 cFYI(0, ("existing dentry with inode 0x%p", tmp_dentry->d_inode));
76                 *ptmp_inode = tmp_dentry->d_inode;
77 /* BB overwrite old name? i.e. tmp_dentry->d_name and tmp_dentry->d_name.len??*/
78                 if(*ptmp_inode == NULL) {
79                         *ptmp_inode = new_inode(file->f_dentry->d_sb);
80                         if(*ptmp_inode == NULL)
81                                 return rc;
82                         rc = 1;
83                         d_instantiate(tmp_dentry, *ptmp_inode);
84                 }
85         } else {
86                 tmp_dentry = d_alloc(file->f_dentry, qstring);
87                 if(tmp_dentry == NULL) {
88                         cERROR(1,("Failed allocating dentry"));
89                         *ptmp_inode = NULL;
90                         return rc;
91                 }
92
93                 *ptmp_inode = new_inode(file->f_dentry->d_sb);
94                 if (pTcon->nocase)
95                         tmp_dentry->d_op = &cifs_ci_dentry_ops;
96                 else
97                         tmp_dentry->d_op = &cifs_dentry_ops;
98                 if(*ptmp_inode == NULL)
99                         return rc;
100                 rc = 1;
101                 d_instantiate(tmp_dentry, *ptmp_inode);
102                 d_rehash(tmp_dentry);
103         }
104
105         tmp_dentry->d_time = jiffies;
106         *pnew_dentry = tmp_dentry;
107         return rc;
108 }
109
110 static void fill_in_inode(struct inode *tmp_inode,
111         FILE_DIRECTORY_INFO *pfindData, int *pobject_type, int isNewInode)
112 {
113         loff_t local_size;
114         struct timespec local_mtime;
115
116         struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
117         struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
118         __u32 attr = le32_to_cpu(pfindData->ExtFileAttributes);
119         __u64 allocation_size = le64_to_cpu(pfindData->AllocationSize);
120         __u64 end_of_file = le64_to_cpu(pfindData->EndOfFile);
121
122         cifsInfo->cifsAttrs = attr;
123         cifsInfo->time = jiffies;
124
125         /* save mtime and size */
126         local_mtime = tmp_inode->i_mtime;
127         local_size  = tmp_inode->i_size;
128
129         /* Linux can not store file creation time unfortunately so ignore it */
130         tmp_inode->i_atime =
131             cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
132         tmp_inode->i_mtime =
133             cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastWriteTime));
134         tmp_inode->i_ctime =
135             cifs_NTtimeToUnix(le64_to_cpu(pfindData->ChangeTime));
136         /* treat dos attribute of read-only as read-only mode bit e.g. 555? */
137         /* 2767 perms - indicate mandatory locking */
138                 /* BB fill in uid and gid here? with help from winbind? 
139                    or retrieve from NTFS stream extended attribute */
140         if (atomic_read(&cifsInfo->inUse) == 0) {
141                 tmp_inode->i_uid = cifs_sb->mnt_uid;
142                 tmp_inode->i_gid = cifs_sb->mnt_gid;
143                 /* set default mode. will override for dirs below */
144                 tmp_inode->i_mode = cifs_sb->mnt_file_mode;
145         } else {
146                 /* mask off the type bits since it gets set
147                 below and we do not want to get two type
148                 bits set */
149                 tmp_inode->i_mode &= ~S_IFMT;
150         }
151
152         if (attr & ATTR_DIRECTORY) {
153                 *pobject_type = DT_DIR;
154                 /* override default perms since we do not lock dirs */
155                 if(atomic_read(&cifsInfo->inUse) == 0) {
156                         tmp_inode->i_mode = cifs_sb->mnt_dir_mode;
157                 }
158                 tmp_inode->i_mode |= S_IFDIR;
159         } else if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) && 
160                    (attr & ATTR_SYSTEM)) {
161                 if (end_of_file == 0)  {
162                         *pobject_type = DT_FIFO;
163                         tmp_inode->i_mode |= S_IFIFO;
164                 } else {
165                         /* rather than get the type here, we mark the
166                         inode as needing revalidate and get the real type
167                         (blk vs chr vs. symlink) later ie in lookup */
168                         *pobject_type = DT_REG;
169                         tmp_inode->i_mode |= S_IFREG; 
170                         cifsInfo->time = 0;     
171                 }
172 /* we no longer mark these because we could not follow them */
173 /*        } else if (attr & ATTR_REPARSE) {
174                 *pobject_type = DT_LNK;
175                 tmp_inode->i_mode |= S_IFLNK; */
176         } else {
177                 *pobject_type = DT_REG;
178                 tmp_inode->i_mode |= S_IFREG;
179                 if (attr & ATTR_READONLY)
180                         tmp_inode->i_mode &= ~(S_IWUGO);
181         } /* could add code here - to validate if device or weird share type? */
182
183         /* can not fill in nlink here as in qpathinfo version and Unx search */
184         if (atomic_read(&cifsInfo->inUse) == 0) {
185                 atomic_set(&cifsInfo->inUse, 1);
186         }
187
188         if (is_size_safe_to_change(cifsInfo)) {
189                 /* can not safely change the file size here if the 
190                 client is writing to it due to potential races */
191                 i_size_write(tmp_inode, end_of_file);
192
193         /* 512 bytes (2**9) is the fake blocksize that must be used */
194         /* for this calculation, even though the reported blocksize is larger */
195                 tmp_inode->i_blocks = (512 - 1 + allocation_size) >> 9;
196         }
197
198         if (allocation_size < end_of_file)
199                 cFYI(1, ("May be sparse file, allocation less than file size"));
200         cFYI(1, ("File Size %ld and blocks %llu and blocksize %ld",
201                 (unsigned long)tmp_inode->i_size,
202                 (unsigned long long)tmp_inode->i_blocks,
203                 tmp_inode->i_blksize));
204         if (S_ISREG(tmp_inode->i_mode)) {
205                 cFYI(1, ("File inode"));
206                 tmp_inode->i_op = &cifs_file_inode_ops;
207                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
208                         if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
209                                 tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
210                         else
211                                 tmp_inode->i_fop = &cifs_file_direct_ops;
212                 
213                 } else if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
214                         tmp_inode->i_fop = &cifs_file_nobrl_ops;
215                 else
216                         tmp_inode->i_fop = &cifs_file_ops;
217
218                 tmp_inode->i_data.a_ops = &cifs_addr_ops;
219                 if((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
220                    (cifs_sb->tcon->ses->server->maxBuf <
221                         4096 + MAX_CIFS_HDR_SIZE))
222                         tmp_inode->i_data.a_ops->readpages = NULL;
223                 if(isNewInode)
224                         return; /* No sense invalidating pages for new inode
225                                    since have not started caching readahead file
226                                    data yet */
227
228                 if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
229                         (local_size == tmp_inode->i_size)) {
230                         cFYI(1, ("inode exists but unchanged"));
231                 } else {
232                         /* file may have changed on server */
233                         cFYI(1, ("invalidate inode, readdir detected change"));
234                         invalidate_remote_inode(tmp_inode);
235                 }
236         } else if (S_ISDIR(tmp_inode->i_mode)) {
237                 cFYI(1, ("Directory inode"));
238                 tmp_inode->i_op = &cifs_dir_inode_ops;
239                 tmp_inode->i_fop = &cifs_dir_ops;
240         } else if (S_ISLNK(tmp_inode->i_mode)) {
241                 cFYI(1, ("Symbolic Link inode"));
242                 tmp_inode->i_op = &cifs_symlink_inode_ops;
243         } else {
244                 cFYI(1, ("Init special inode"));
245                 init_special_inode(tmp_inode, tmp_inode->i_mode,
246                                    tmp_inode->i_rdev);
247         }
248 }
249
250 static void unix_fill_in_inode(struct inode *tmp_inode,
251         FILE_UNIX_INFO *pfindData, int *pobject_type, int isNewInode)
252 {
253         loff_t local_size;
254         struct timespec local_mtime;
255
256         struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
257         struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
258
259         __u32 type = le32_to_cpu(pfindData->Type);
260         __u64 num_of_bytes = le64_to_cpu(pfindData->NumOfBytes);
261         __u64 end_of_file = le64_to_cpu(pfindData->EndOfFile);
262         cifsInfo->time = jiffies;
263         atomic_inc(&cifsInfo->inUse);
264
265         /* save mtime and size */
266         local_mtime = tmp_inode->i_mtime;
267         local_size  = tmp_inode->i_size;
268
269         tmp_inode->i_atime =
270             cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
271         tmp_inode->i_mtime =
272             cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastModificationTime));
273         tmp_inode->i_ctime =
274             cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastStatusChange));
275
276         tmp_inode->i_mode = le64_to_cpu(pfindData->Permissions);
277         /* since we set the inode type below we need to mask off type
278            to avoid strange results if bits above were corrupt */
279         tmp_inode->i_mode &= ~S_IFMT;
280         if (type == UNIX_FILE) {
281                 *pobject_type = DT_REG;
282                 tmp_inode->i_mode |= S_IFREG;
283         } else if (type == UNIX_SYMLINK) {
284                 *pobject_type = DT_LNK;
285                 tmp_inode->i_mode |= S_IFLNK;
286         } else if (type == UNIX_DIR) {
287                 *pobject_type = DT_DIR;
288                 tmp_inode->i_mode |= S_IFDIR;
289         } else if (type == UNIX_CHARDEV) {
290                 *pobject_type = DT_CHR;
291                 tmp_inode->i_mode |= S_IFCHR;
292                 tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
293                                 le64_to_cpu(pfindData->DevMinor) & MINORMASK);
294         } else if (type == UNIX_BLOCKDEV) {
295                 *pobject_type = DT_BLK;
296                 tmp_inode->i_mode |= S_IFBLK;
297                 tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
298                                 le64_to_cpu(pfindData->DevMinor) & MINORMASK);
299         } else if (type == UNIX_FIFO) {
300                 *pobject_type = DT_FIFO;
301                 tmp_inode->i_mode |= S_IFIFO;
302         } else if (type == UNIX_SOCKET) {
303                 *pobject_type = DT_SOCK;
304                 tmp_inode->i_mode |= S_IFSOCK;
305         } else {
306                 /* safest to just call it a file */
307                 *pobject_type = DT_REG;
308                 tmp_inode->i_mode |= S_IFREG;
309                 cFYI(1,("unknown inode type %d",type)); 
310         }
311
312         tmp_inode->i_uid = le64_to_cpu(pfindData->Uid);
313         tmp_inode->i_gid = le64_to_cpu(pfindData->Gid);
314         tmp_inode->i_nlink = le64_to_cpu(pfindData->Nlinks);
315
316         if (is_size_safe_to_change(cifsInfo)) {
317                 /* can not safely change the file size here if the 
318                 client is writing to it due to potential races */
319                 i_size_write(tmp_inode,end_of_file);
320
321         /* 512 bytes (2**9) is the fake blocksize that must be used */
322         /* for this calculation, not the real blocksize */
323                 tmp_inode->i_blocks = (512 - 1 + num_of_bytes) >> 9;
324         }
325
326         if (S_ISREG(tmp_inode->i_mode)) {
327                 cFYI(1, ("File inode"));
328                 tmp_inode->i_op = &cifs_file_inode_ops;
329
330                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
331                         if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
332                                 tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
333                         else
334                                 tmp_inode->i_fop = &cifs_file_direct_ops;
335                 
336                 } else if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
337                         tmp_inode->i_fop = &cifs_file_nobrl_ops;
338                 else
339                         tmp_inode->i_fop = &cifs_file_ops;
340
341                 tmp_inode->i_data.a_ops = &cifs_addr_ops;
342                 if((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
343                    (cifs_sb->tcon->ses->server->maxBuf < 
344                         4096 + MAX_CIFS_HDR_SIZE))
345                         tmp_inode->i_data.a_ops->readpages = NULL;
346
347                 if(isNewInode)
348                         return; /* No sense invalidating pages for new inode since we
349                                            have not started caching readahead file data yet */
350
351                 if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
352                         (local_size == tmp_inode->i_size)) {
353                         cFYI(1, ("inode exists but unchanged"));
354                 } else {
355                         /* file may have changed on server */
356                         cFYI(1, ("invalidate inode, readdir detected change"));
357                         invalidate_remote_inode(tmp_inode);
358                 }
359         } else if (S_ISDIR(tmp_inode->i_mode)) {
360                 cFYI(1, ("Directory inode"));
361                 tmp_inode->i_op = &cifs_dir_inode_ops;
362                 tmp_inode->i_fop = &cifs_dir_ops;
363         } else if (S_ISLNK(tmp_inode->i_mode)) {
364                 cFYI(1, ("Symbolic Link inode"));
365                 tmp_inode->i_op = &cifs_symlink_inode_ops;
366 /* tmp_inode->i_fop = *//* do not need to set to anything */
367         } else {
368                 cFYI(1, ("Special inode")); 
369                 init_special_inode(tmp_inode, tmp_inode->i_mode,
370                                    tmp_inode->i_rdev);
371         }
372 }
373
374 static int initiate_cifs_search(const int xid, struct file *file)
375 {
376         int rc = 0;
377         char * full_path;
378         struct cifsFileInfo * cifsFile;
379         struct cifs_sb_info *cifs_sb;
380         struct cifsTconInfo *pTcon;
381
382         if(file->private_data == NULL) {
383                 file->private_data = 
384                         kmalloc(sizeof(struct cifsFileInfo),GFP_KERNEL);
385         }
386
387         if(file->private_data == NULL) {
388                 return -ENOMEM;
389         } else {
390                 memset(file->private_data,0,sizeof(struct cifsFileInfo));
391         }
392         cifsFile = file->private_data;
393         cifsFile->invalidHandle = TRUE;
394         cifsFile->srch_inf.endOfSearch = FALSE;
395
396         if(file->f_dentry == NULL)
397                 return -ENOENT;
398
399         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
400         if(cifs_sb == NULL)
401                 return -EINVAL;
402
403         pTcon = cifs_sb->tcon;
404         if(pTcon == NULL)
405                 return -EINVAL;
406
407         full_path = build_path_from_dentry(file->f_dentry);
408
409         if(full_path == NULL) {
410                 return -ENOMEM;
411         }
412
413         cFYI(1, ("Full path: %s start at: %lld", full_path, file->f_pos));
414
415 ffirst_retry:
416         /* test for Unix extensions */
417         if (pTcon->ses->capabilities & CAP_UNIX) {
418                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX; 
419         } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
420                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
421         } else /* not srvinos - BB fixme add check for backlevel? */ {
422                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
423         }
424
425         rc = CIFSFindFirst(xid, pTcon,full_path,cifs_sb->local_nls,
426                 &cifsFile->netfid, &cifsFile->srch_inf,
427                 cifs_sb->mnt_cifs_flags & 
428                         CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
429         if(rc == 0)
430                 cifsFile->invalidHandle = FALSE;
431         if((rc == -EOPNOTSUPP) && 
432                 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
433                 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
434                 goto ffirst_retry;
435         }
436         kfree(full_path);
437         return rc;
438 }
439
440 /* return length of unicode string in bytes */
441 static int cifs_unicode_bytelen(char *str)
442 {
443         int len;
444         __le16 * ustr = (__le16 *)str;
445
446         for(len=0;len <= PATH_MAX;len++) {
447                 if(ustr[len] == 0)
448                         return len << 1;
449         }
450         cFYI(1,("Unicode string longer than PATH_MAX found"));
451         return len << 1;
452 }
453
454 static char *nxt_dir_entry(char *old_entry, char *end_of_smb)
455 {
456         char * new_entry;
457         FILE_DIRECTORY_INFO * pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
458
459         new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
460         cFYI(1,("new entry %p old entry %p",new_entry,old_entry));
461         /* validate that new_entry is not past end of SMB */
462         if(new_entry >= end_of_smb) {
463                 cERROR(1,
464                       ("search entry %p began after end of SMB %p old entry %p",
465                         new_entry, end_of_smb, old_entry)); 
466                 return NULL;
467         } else if (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb) {
468                 cERROR(1,("search entry %p extends after end of SMB %p",
469                         new_entry, end_of_smb));
470                 return NULL;
471         } else 
472                 return new_entry;
473
474 }
475
476 #define UNICODE_DOT cpu_to_le16(0x2e)
477
478 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
479 static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
480 {
481         int rc = 0;
482         char * filename = NULL;
483         int len = 0; 
484
485         if(cfile->srch_inf.info_level == 0x202) {
486                 FILE_UNIX_INFO * pFindData = (FILE_UNIX_INFO *)current_entry;
487                 filename = &pFindData->FileName[0];
488                 if(cfile->srch_inf.unicode) {
489                         len = cifs_unicode_bytelen(filename);
490                 } else {
491                         /* BB should we make this strnlen of PATH_MAX? */
492                         len = strnlen(filename, 5);
493                 }
494         } else if(cfile->srch_inf.info_level == 0x101) {
495                 FILE_DIRECTORY_INFO * pFindData = 
496                         (FILE_DIRECTORY_INFO *)current_entry;
497                 filename = &pFindData->FileName[0];
498                 len = le32_to_cpu(pFindData->FileNameLength);
499         } else if(cfile->srch_inf.info_level == 0x102) {
500                 FILE_FULL_DIRECTORY_INFO * pFindData = 
501                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
502                 filename = &pFindData->FileName[0];
503                 len = le32_to_cpu(pFindData->FileNameLength);
504         } else if(cfile->srch_inf.info_level == 0x105) {
505                 SEARCH_ID_FULL_DIR_INFO * pFindData = 
506                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
507                 filename = &pFindData->FileName[0];
508                 len = le32_to_cpu(pFindData->FileNameLength);
509         } else if(cfile->srch_inf.info_level == 0x104) {
510                 FILE_BOTH_DIRECTORY_INFO * pFindData = 
511                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
512                 filename = &pFindData->FileName[0];
513                 len = le32_to_cpu(pFindData->FileNameLength);
514         } else {
515                 cFYI(1,("Unknown findfirst level %d",cfile->srch_inf.info_level));
516         }
517
518         if(filename) {
519                 if(cfile->srch_inf.unicode) {
520                         __le16 *ufilename = (__le16 *)filename;
521                         if(len == 2) {
522                                 /* check for . */
523                                 if(ufilename[0] == UNICODE_DOT)
524                                         rc = 1;
525                         } else if(len == 4) {
526                                 /* check for .. */
527                                 if((ufilename[0] == UNICODE_DOT)
528                                    &&(ufilename[1] == UNICODE_DOT))
529                                         rc = 2;
530                         }
531                 } else /* ASCII */ {
532                         if(len == 1) {
533                                 if(filename[0] == '.') 
534                                         rc = 1;
535                         } else if(len == 2) {
536                                 if((filename[0] == '.') && (filename[1] == '.')) 
537                                         rc = 2;
538                         }
539                 }
540         }
541
542         return rc;
543 }
544
545 /* Check if directory that we are searching has changed so we can decide
546    whether we can use the cached search results from the previous search */
547 static int is_dir_changed(struct file * file)
548 {
549         struct inode * inode;
550         struct cifsInodeInfo *cifsInfo;
551
552         if(file->f_dentry == NULL)
553                 return 0;
554
555         inode = file->f_dentry->d_inode;
556
557         if(inode == NULL)
558                 return 0;
559
560         cifsInfo = CIFS_I(inode);
561
562         if(cifsInfo->time == 0)
563                 return 1; /* directory was changed, perhaps due to unlink */
564         else
565                 return 0;
566
567 }
568
569 /* find the corresponding entry in the search */
570 /* Note that the SMB server returns search entries for . and .. which
571    complicates logic here if we choose to parse for them and we do not
572    assume that they are located in the findfirst return buffer.*/
573 /* We start counting in the buffer with entry 2 and increment for every
574    entry (do not increment for . or .. entry) */
575 static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
576         struct file *file, char **ppCurrentEntry, int *num_to_ret) 
577 {
578         int rc = 0;
579         int pos_in_buf = 0;
580         loff_t first_entry_in_buffer;
581         loff_t index_to_find = file->f_pos;
582         struct cifsFileInfo * cifsFile = file->private_data;
583         /* check if index in the buffer */
584         
585         if((cifsFile == NULL) || (ppCurrentEntry == NULL) || 
586            (num_to_ret == NULL))
587                 return -ENOENT;
588         
589         *ppCurrentEntry = NULL;
590         first_entry_in_buffer = 
591                 cifsFile->srch_inf.index_of_last_entry - 
592                         cifsFile->srch_inf.entries_in_buffer;
593
594         /* if first entry in buf is zero then is first buffer
595         in search response data which means it is likely . and ..
596         will be in this buffer, although some servers do not return
597         . and .. for the root of a drive and for those we need
598         to start two entries earlier */
599
600 /*      dump_cifs_file_struct(file, "In fce ");*/
601         if(((index_to_find < cifsFile->srch_inf.index_of_last_entry) && 
602              is_dir_changed(file)) || 
603            (index_to_find < first_entry_in_buffer)) {
604                 /* close and restart search */
605                 cFYI(1,("search backing up - close and restart search"));
606                 cifsFile->invalidHandle = TRUE;
607                 CIFSFindClose(xid, pTcon, cifsFile->netfid);
608                 kfree(cifsFile->search_resume_name);
609                 cifsFile->search_resume_name = NULL;
610                 if(cifsFile->srch_inf.ntwrk_buf_start) {
611                         cFYI(1,("freeing SMB ff cache buf on search rewind"));
612                         if(cifsFile->srch_inf.smallBuf)
613                                 cifs_small_buf_release(cifsFile->srch_inf.
614                                                 ntwrk_buf_start);
615                         else
616                                 cifs_buf_release(cifsFile->srch_inf.
617                                                 ntwrk_buf_start);
618                 }
619                 rc = initiate_cifs_search(xid,file);
620                 if(rc) {
621                         cFYI(1,("error %d reinitiating a search on rewind",rc));
622                         return rc;
623                 }
624         }
625
626         while((index_to_find >= cifsFile->srch_inf.index_of_last_entry) && 
627               (rc == 0) && (cifsFile->srch_inf.endOfSearch == FALSE)){
628                 cFYI(1,("calling findnext2"));
629                 rc = CIFSFindNext(xid,pTcon,cifsFile->netfid, 
630                                   &cifsFile->srch_inf);
631                 if(rc)
632                         return -ENOENT;
633         }
634         if(index_to_find < cifsFile->srch_inf.index_of_last_entry) {
635                 /* we found the buffer that contains the entry */
636                 /* scan and find it */
637                 int i;
638                 char * current_entry;
639                 char * end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + 
640                         smbCalcSize((struct smb_hdr *)
641                                 cifsFile->srch_inf.ntwrk_buf_start);
642
643                 current_entry = cifsFile->srch_inf.srch_entries_start;
644                 first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
645                                         - cifsFile->srch_inf.entries_in_buffer;
646                 pos_in_buf = index_to_find - first_entry_in_buffer;
647                 cFYI(1,("found entry - pos_in_buf %d",pos_in_buf)); 
648                 for(i=0;(i<(pos_in_buf)) && (current_entry != NULL);i++) {
649                         /* go entry by entry figuring out which is first */
650                         current_entry = nxt_dir_entry(current_entry,end_of_smb);
651                 }
652                 if((current_entry == NULL) && (i < pos_in_buf)) {
653                         /* BB fixme - check if we should flag this error */
654                         cERROR(1,("reached end of buf searching for pos in buf"
655                           " %d index to find %lld rc %d",
656                           pos_in_buf,index_to_find,rc));
657                 }
658                 rc = 0;
659                 *ppCurrentEntry = current_entry;
660         } else {
661                 cFYI(1,("index not in buffer - could not findnext into it"));
662                 return 0;
663         }
664
665         if(pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
666                 cFYI(1,("can not return entries pos_in_buf beyond last entry"));
667                 *num_to_ret = 0;
668         } else
669                 *num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
670
671         return rc;
672 }
673
674 /* inode num, inode type and filename returned */
675 static int cifs_get_name_from_search_buf(struct qstr *pqst,
676         char *current_entry, __u16 level, unsigned int unicode,
677         struct cifs_sb_info * cifs_sb, ino_t *pinum)
678 {
679         int rc = 0;
680         unsigned int len = 0;
681         char * filename;
682         struct nls_table * nlt = cifs_sb->local_nls;
683
684         *pinum = 0;
685
686         if(level == SMB_FIND_FILE_UNIX) {
687                 FILE_UNIX_INFO * pFindData = (FILE_UNIX_INFO *)current_entry;
688
689                 filename = &pFindData->FileName[0];
690                 if(unicode) {
691                         len = cifs_unicode_bytelen(filename);
692                 } else {
693                         /* BB should we make this strnlen of PATH_MAX? */
694                         len = strnlen(filename, PATH_MAX);
695                 }
696
697                 /* BB fixme - hash low and high 32 bits if not 64 bit arch BB fixme */
698                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)
699                         *pinum = pFindData->UniqueId;
700         } else if(level == SMB_FIND_FILE_DIRECTORY_INFO) {
701                 FILE_DIRECTORY_INFO * pFindData = 
702                         (FILE_DIRECTORY_INFO *)current_entry;
703                 filename = &pFindData->FileName[0];
704                 len = le32_to_cpu(pFindData->FileNameLength);
705         } else if(level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
706                 FILE_FULL_DIRECTORY_INFO * pFindData = 
707                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
708                 filename = &pFindData->FileName[0];
709                 len = le32_to_cpu(pFindData->FileNameLength);
710         } else if(level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
711                 SEARCH_ID_FULL_DIR_INFO * pFindData = 
712                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
713                 filename = &pFindData->FileName[0];
714                 len = le32_to_cpu(pFindData->FileNameLength);
715                 *pinum = pFindData->UniqueId;
716         } else if(level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
717                 FILE_BOTH_DIRECTORY_INFO * pFindData = 
718                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
719                 filename = &pFindData->FileName[0];
720                 len = le32_to_cpu(pFindData->FileNameLength);
721         } else {
722                 cFYI(1,("Unknown findfirst level %d",level));
723                 return -EINVAL;
724         }
725         if(unicode) {
726                 /* BB fixme - test with long names */
727                 /* Note converted filename can be longer than in unicode */
728                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
729                         pqst->len = cifs_convertUCSpath((char *)pqst->name,
730                                         (__le16 *)filename, len/2, nlt);
731                 else
732                         pqst->len = cifs_strfromUCS_le((char *)pqst->name,
733                                         (__le16 *)filename,len/2,nlt);
734         } else {
735                 pqst->name = filename;
736                 pqst->len = len;
737         }
738         pqst->hash = full_name_hash(pqst->name,pqst->len);
739 /*      cFYI(1,("filldir on %s",pqst->name));  */
740         return rc;
741 }
742
743 static int cifs_filldir(char *pfindEntry, struct file *file,
744         filldir_t filldir, void *direntry, char *scratch_buf)
745 {
746         int rc = 0;
747         struct qstr qstring;
748         struct cifsFileInfo * pCifsF;
749         unsigned obj_type;
750         ino_t  inum;
751         struct cifs_sb_info * cifs_sb;
752         struct inode *tmp_inode;
753         struct dentry *tmp_dentry;
754
755         /* get filename and len into qstring */
756         /* get dentry */
757         /* decide whether to create and populate ionde */
758         if((direntry == NULL) || (file == NULL))
759                 return -EINVAL;
760
761         pCifsF = file->private_data;
762         
763         if((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
764                 return -ENOENT;
765
766         if(file->f_dentry == NULL)
767                 return -ENOENT;
768
769         rc = cifs_entry_is_dot(pfindEntry,pCifsF);
770         /* skip . and .. since we added them first */
771         if(rc != 0) 
772                 return 0;
773
774         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
775
776         qstring.name = scratch_buf;
777         rc = cifs_get_name_from_search_buf(&qstring,pfindEntry,
778                         pCifsF->srch_inf.info_level,
779                         pCifsF->srch_inf.unicode,cifs_sb,
780                         &inum /* returned */);
781
782         if(rc)
783                 return rc;
784
785         rc = construct_dentry(&qstring,file,&tmp_inode, &tmp_dentry);
786         if((tmp_inode == NULL) || (tmp_dentry == NULL))
787                 return -ENOMEM;
788
789         if(rc) {
790                 /* inode created, we need to hash it with right inode number */
791                 if(inum != 0) {
792                         /* BB fixme - hash the 2 32 quantities bits together if necessary BB */
793                         tmp_inode->i_ino = inum;
794                 }
795                 insert_inode_hash(tmp_inode);
796         }
797
798         /* we pass in rc below, indicating whether it is a new inode,
799            so we can figure out whether to invalidate the inode cached
800            data if the file has changed */
801         if(pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
802                 unix_fill_in_inode(tmp_inode,
803                                    (FILE_UNIX_INFO *)pfindEntry,&obj_type, rc);
804         } else {
805                 fill_in_inode(tmp_inode,
806                               (FILE_DIRECTORY_INFO *)pfindEntry,&obj_type, rc);
807         }
808         
809         rc = filldir(direntry,qstring.name,qstring.len,file->f_pos,
810                      tmp_inode->i_ino,obj_type);
811         if(rc) {
812                 cFYI(1,("filldir rc = %d",rc));
813         }
814
815         dput(tmp_dentry);
816         return rc;
817 }
818
819 static int cifs_save_resume_key(const char *current_entry,
820         struct cifsFileInfo *cifsFile)
821 {
822         int rc = 0;
823         unsigned int len = 0;
824         __u16 level;
825         char * filename;
826
827         if((cifsFile == NULL) || (current_entry == NULL))
828                 return -EINVAL;
829
830         level = cifsFile->srch_inf.info_level;
831
832         if(level == SMB_FIND_FILE_UNIX) {
833                 FILE_UNIX_INFO * pFindData = (FILE_UNIX_INFO *)current_entry;
834
835                 filename = &pFindData->FileName[0];
836                 if(cifsFile->srch_inf.unicode) {
837                         len = cifs_unicode_bytelen(filename);
838                 } else {
839                         /* BB should we make this strnlen of PATH_MAX? */
840                         len = strnlen(filename, PATH_MAX);
841                 }
842                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
843         } else if(level == SMB_FIND_FILE_DIRECTORY_INFO) {
844                 FILE_DIRECTORY_INFO * pFindData = 
845                         (FILE_DIRECTORY_INFO *)current_entry;
846                 filename = &pFindData->FileName[0];
847                 len = le32_to_cpu(pFindData->FileNameLength);
848                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
849         } else if(level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
850                 FILE_FULL_DIRECTORY_INFO * pFindData = 
851                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
852                 filename = &pFindData->FileName[0];
853                 len = le32_to_cpu(pFindData->FileNameLength);
854                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
855         } else if(level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
856                 SEARCH_ID_FULL_DIR_INFO * pFindData = 
857                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
858                 filename = &pFindData->FileName[0];
859                 len = le32_to_cpu(pFindData->FileNameLength);
860                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
861         } else if(level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
862                 FILE_BOTH_DIRECTORY_INFO * pFindData = 
863                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
864                 filename = &pFindData->FileName[0];
865                 len = le32_to_cpu(pFindData->FileNameLength);
866                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
867         } else {
868                 cFYI(1,("Unknown findfirst level %d",level));
869                 return -EINVAL;
870         }
871         cifsFile->srch_inf.resume_name_len = len;
872         cifsFile->srch_inf.presume_name = filename;
873         return rc;
874 }
875
876 int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
877 {
878         int rc = 0;
879         int xid,i;
880         struct cifs_sb_info *cifs_sb;
881         struct cifsTconInfo *pTcon;
882         struct cifsFileInfo *cifsFile = NULL;
883         char * current_entry;
884         int num_to_fill = 0;
885         char * tmp_buf = NULL;
886         char * end_of_smb;
887
888         xid = GetXid();
889
890         if(file->f_dentry == NULL) {
891                 FreeXid(xid);
892                 return -EIO;
893         }
894
895         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
896         pTcon = cifs_sb->tcon;
897         if(pTcon == NULL)
898                 return -EINVAL;
899
900         switch ((int) file->f_pos) {
901         case 0:
902                 if (filldir(direntry, ".", 1, file->f_pos,
903                      file->f_dentry->d_inode->i_ino, DT_DIR) < 0) {
904                         cERROR(1, ("Filldir for current dir failed"));
905                         rc = -ENOMEM;
906                         break;
907                 }
908                 file->f_pos++;
909         case 1:
910                 if (filldir(direntry, "..", 2, file->f_pos,
911                      file->f_dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
912                         cERROR(1, ("Filldir for parent dir failed"));
913                         rc = -ENOMEM;
914                         break;
915                 }
916                 file->f_pos++;
917         default:
918                 /* 1) If search is active, 
919                         is in current search buffer? 
920                         if it before then restart search
921                         if after then keep searching till find it */
922
923                 if(file->private_data == NULL) {
924                         rc = initiate_cifs_search(xid,file);
925                         cFYI(1,("initiate cifs search rc %d",rc));
926                         if(rc) {
927                                 FreeXid(xid);
928                                 return rc;
929                         }
930                 }
931                 if(file->private_data == NULL) {
932                         rc = -EINVAL;
933                         FreeXid(xid);
934                         return rc;
935                 }
936                 cifsFile = file->private_data;
937                 if (cifsFile->srch_inf.endOfSearch) {
938                         if(cifsFile->srch_inf.emptyDir) {
939                                 cFYI(1, ("End of search, empty dir"));
940                                 rc = 0;
941                                 break;
942                         }
943                 } /* else {
944                         cifsFile->invalidHandle = TRUE;
945                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
946                 } 
947                 kfree(cifsFile->search_resume_name);
948                 cifsFile->search_resume_name = NULL; */
949
950                 rc = find_cifs_entry(xid,pTcon, file,
951                                 &current_entry,&num_to_fill);
952                 if(rc) {
953                         cFYI(1,("fce error %d",rc)); 
954                         goto rddir2_exit;
955                 } else if (current_entry != NULL) {
956                         cFYI(1,("entry %lld found",file->f_pos));
957                 } else {
958                         cFYI(1,("could not find entry"));
959                         goto rddir2_exit;
960                 }
961                 cFYI(1,("loop through %d times filling dir for net buf %p",
962                         num_to_fill,cifsFile->srch_inf.ntwrk_buf_start)); 
963                 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
964                         smbCalcSize((struct smb_hdr *)
965                                     cifsFile->srch_inf.ntwrk_buf_start);
966                 /* To be safe - for UCS to UTF-8 with strings loaded
967                 with the rare long characters alloc more to account for
968                 such multibyte target UTF-8 characters. cifs_unicode.c,
969                 which actually does the conversion, has the same limit */
970                 tmp_buf = kmalloc((2 * NAME_MAX) + 4, GFP_KERNEL);
971                 for(i=0;(i<num_to_fill) && (rc == 0);i++) {
972                         if(current_entry == NULL) {
973                                 /* evaluate whether this case is an error */
974                                 cERROR(1,("past end of SMB num to fill %d i %d",
975                                           num_to_fill, i));
976                                 break;
977                         }
978                         /* if buggy server returns . and .. late do
979                         we want to check for that here? */
980                         rc = cifs_filldir(current_entry, file, 
981                                         filldir, direntry,tmp_buf);
982                         file->f_pos++;
983                         if(file->f_pos == cifsFile->srch_inf.index_of_last_entry) {
984                                 cFYI(1,("last entry in buf at pos %lld %s",
985                                         file->f_pos,tmp_buf)); /* BB removeme BB */
986                                 cifs_save_resume_key(current_entry,cifsFile);
987                                 break;
988                         } else 
989                                 current_entry = nxt_dir_entry(current_entry,
990                                                               end_of_smb);
991                 }
992                 kfree(tmp_buf);
993                 break;
994         } /* end switch */
995
996 rddir2_exit:
997         FreeXid(xid);
998         return rc;
999 }