Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[sfrench/cifs-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, 2008
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/pagemap.h>
25 #include <linux/stat.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 /*
35  * To be safe - for UCS to UTF-8 with strings loaded with the rare long
36  * characters alloc more to account for such multibyte target UTF-8
37  * characters.
38  */
39 #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
40
41 #ifdef CONFIG_CIFS_DEBUG2
42 static void dump_cifs_file_struct(struct file *file, char *label)
43 {
44         struct cifsFileInfo *cf;
45
46         if (file) {
47                 cf = file->private_data;
48                 if (cf == NULL) {
49                         cFYI(1, ("empty cifs private file data"));
50                         return;
51                 }
52                 if (cf->invalidHandle)
53                         cFYI(1, ("invalid handle"));
54                 if (cf->srch_inf.endOfSearch)
55                         cFYI(1, ("end of search"));
56                 if (cf->srch_inf.emptyDir)
57                         cFYI(1, ("empty dir"));
58         }
59 }
60 #else
61 static inline void dump_cifs_file_struct(struct file *file, char *label)
62 {
63 }
64 #endif /* DEBUG2 */
65
66 /*
67  * Find the dentry that matches "name". If there isn't one, create one. If it's
68  * a negative dentry or the uniqueid changed, then drop it and recreate it.
69  */
70 static struct dentry *
71 cifs_readdir_lookup(struct dentry *parent, struct qstr *name,
72                     struct cifs_fattr *fattr)
73 {
74         struct dentry *dentry, *alias;
75         struct inode *inode;
76         struct super_block *sb = parent->d_inode->i_sb;
77
78         cFYI(1, ("For %s", name->name));
79
80         dentry = d_lookup(parent, name);
81         if (dentry) {
82                 /* FIXME: check for inode number changes? */
83                 if (dentry->d_inode != NULL)
84                         return dentry;
85                 d_drop(dentry);
86                 dput(dentry);
87         }
88
89         dentry = d_alloc(parent, name);
90         if (dentry == NULL)
91                 return NULL;
92
93         inode = cifs_iget(sb, fattr);
94         if (!inode) {
95                 dput(dentry);
96                 return NULL;
97         }
98
99         if (CIFS_SB(sb)->tcon->nocase)
100                 dentry->d_op = &cifs_ci_dentry_ops;
101         else
102                 dentry->d_op = &cifs_dentry_ops;
103
104         alias = d_materialise_unique(dentry, inode);
105         if (alias != NULL) {
106                 dput(dentry);
107                 if (IS_ERR(alias))
108                         return NULL;
109                 dentry = alias;
110         }
111
112         return dentry;
113 }
114
115 static void
116 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
117 {
118         fattr->cf_uid = cifs_sb->mnt_uid;
119         fattr->cf_gid = cifs_sb->mnt_gid;
120
121         if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
122                 fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
123                 fattr->cf_dtype = DT_DIR;
124         } else {
125                 fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
126                 fattr->cf_dtype = DT_REG;
127         }
128
129         if (fattr->cf_cifsattrs & ATTR_READONLY)
130                 fattr->cf_mode &= ~S_IWUGO;
131
132         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
133             fattr->cf_cifsattrs & ATTR_SYSTEM) {
134                 if (fattr->cf_eof == 0)  {
135                         fattr->cf_mode &= ~S_IFMT;
136                         fattr->cf_mode |= S_IFIFO;
137                         fattr->cf_dtype = DT_FIFO;
138                 } else {
139                         /*
140                          * trying to get the type and mode via SFU can be slow,
141                          * so just call those regular files for now, and mark
142                          * for reval
143                          */
144                         fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
145                 }
146         }
147 }
148
149 void
150 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
151                        struct cifs_sb_info *cifs_sb)
152 {
153         memset(fattr, 0, sizeof(*fattr));
154         fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
155         fattr->cf_eof = le64_to_cpu(info->EndOfFile);
156         fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
157         fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
158         fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
159         fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
160
161         cifs_fill_common_info(fattr, cifs_sb);
162 }
163
164 void
165 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
166                        struct cifs_sb_info *cifs_sb)
167 {
168         int offset = cifs_sb->tcon->ses->server->timeAdj;
169
170         memset(fattr, 0, sizeof(*fattr));
171         fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
172                                             info->LastAccessTime, offset);
173         fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
174                                             info->LastWriteTime, offset);
175         fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
176                                             info->LastWriteTime, offset);
177
178         fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
179         fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
180         fattr->cf_eof = le32_to_cpu(info->DataSize);
181
182         cifs_fill_common_info(fattr, cifs_sb);
183 }
184
185 /* BB eventually need to add the following helper function to
186       resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
187       we try to do FindFirst on (NTFS) directory symlinks */
188 /*
189 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
190                              int xid)
191 {
192         __u16 fid;
193         int len;
194         int oplock = 0;
195         int rc;
196         struct cifsTconInfo *ptcon = cifs_sb->tcon;
197         char *tmpbuffer;
198
199         rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
200                         OPEN_REPARSE_POINT, &fid, &oplock, NULL,
201                         cifs_sb->local_nls,
202                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
203         if (!rc) {
204                 tmpbuffer = kmalloc(maxpath);
205                 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
206                                 tmpbuffer,
207                                 maxpath -1,
208                                 fid,
209                                 cifs_sb->local_nls);
210                 if (CIFSSMBClose(xid, ptcon, fid)) {
211                         cFYI(1, ("Error closing temporary reparsepoint open)"));
212                 }
213         }
214 }
215  */
216
217 static int initiate_cifs_search(const int xid, struct file *file)
218 {
219         int rc = 0;
220         char *full_path;
221         struct cifsFileInfo *cifsFile;
222         struct cifs_sb_info *cifs_sb;
223         struct cifsTconInfo *pTcon;
224
225         if (file->private_data == NULL) {
226                 file->private_data =
227                         kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
228         }
229
230         if (file->private_data == NULL)
231                 return -ENOMEM;
232         cifsFile = file->private_data;
233         cifsFile->invalidHandle = true;
234         cifsFile->srch_inf.endOfSearch = false;
235
236         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
237         if (cifs_sb == NULL)
238                 return -EINVAL;
239
240         pTcon = cifs_sb->tcon;
241         if (pTcon == NULL)
242                 return -EINVAL;
243
244         full_path = build_path_from_dentry(file->f_path.dentry);
245
246         if (full_path == NULL)
247                 return -ENOMEM;
248
249         cFYI(1, ("Full path: %s start at: %lld", full_path, file->f_pos));
250
251 ffirst_retry:
252         /* test for Unix extensions */
253         /* but now check for them on the share/mount not on the SMB session */
254 /*      if (pTcon->ses->capabilities & CAP_UNIX) { */
255         if (pTcon->unix_ext)
256                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
257         else if ((pTcon->ses->capabilities &
258                         (CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
259                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
260         } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
261                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
262         } else /* not srvinos - BB fixme add check for backlevel? */ {
263                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
264         }
265
266         rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
267                 &cifsFile->netfid, &cifsFile->srch_inf,
268                 cifs_sb->mnt_cifs_flags &
269                         CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
270         if (rc == 0)
271                 cifsFile->invalidHandle = false;
272         /* BB add following call to handle readdir on new NTFS symlink errors
273         else if STATUS_STOPPED_ON_SYMLINK
274                 call get_symlink_reparse_path and retry with new path */
275         else if ((rc == -EOPNOTSUPP) &&
276                 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
277                 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
278                 goto ffirst_retry;
279         }
280         kfree(full_path);
281         return rc;
282 }
283
284 /* return length of unicode string in bytes */
285 static int cifs_unicode_bytelen(char *str)
286 {
287         int len;
288         __le16 *ustr = (__le16 *)str;
289
290         for (len = 0; len <= PATH_MAX; len++) {
291                 if (ustr[len] == 0)
292                         return len << 1;
293         }
294         cFYI(1, ("Unicode string longer than PATH_MAX found"));
295         return len << 1;
296 }
297
298 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
299 {
300         char *new_entry;
301         FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
302
303         if (level == SMB_FIND_FILE_INFO_STANDARD) {
304                 FIND_FILE_STANDARD_INFO *pfData;
305                 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
306
307                 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
308                                 pfData->FileNameLength;
309         } else
310                 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
311         cFYI(1, ("new entry %p old entry %p", new_entry, old_entry));
312         /* validate that new_entry is not past end of SMB */
313         if (new_entry >= end_of_smb) {
314                 cERROR(1,
315                       ("search entry %p began after end of SMB %p old entry %p",
316                         new_entry, end_of_smb, old_entry));
317                 return NULL;
318         } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
319                     (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
320                   || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
321                    (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
322                 cERROR(1, ("search entry %p extends after end of SMB %p",
323                         new_entry, end_of_smb));
324                 return NULL;
325         } else
326                 return new_entry;
327
328 }
329
330 #define UNICODE_DOT cpu_to_le16(0x2e)
331
332 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
333 static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
334 {
335         int rc = 0;
336         char *filename = NULL;
337         int len = 0;
338
339         if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
340                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
341                 filename = &pFindData->FileName[0];
342                 if (cfile->srch_inf.unicode) {
343                         len = cifs_unicode_bytelen(filename);
344                 } else {
345                         /* BB should we make this strnlen of PATH_MAX? */
346                         len = strnlen(filename, 5);
347                 }
348         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
349                 FILE_DIRECTORY_INFO *pFindData =
350                         (FILE_DIRECTORY_INFO *)current_entry;
351                 filename = &pFindData->FileName[0];
352                 len = le32_to_cpu(pFindData->FileNameLength);
353         } else if (cfile->srch_inf.info_level ==
354                         SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
355                 FILE_FULL_DIRECTORY_INFO *pFindData =
356                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
357                 filename = &pFindData->FileName[0];
358                 len = le32_to_cpu(pFindData->FileNameLength);
359         } else if (cfile->srch_inf.info_level ==
360                         SMB_FIND_FILE_ID_FULL_DIR_INFO) {
361                 SEARCH_ID_FULL_DIR_INFO *pFindData =
362                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
363                 filename = &pFindData->FileName[0];
364                 len = le32_to_cpu(pFindData->FileNameLength);
365         } else if (cfile->srch_inf.info_level ==
366                         SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
367                 FILE_BOTH_DIRECTORY_INFO *pFindData =
368                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
369                 filename = &pFindData->FileName[0];
370                 len = le32_to_cpu(pFindData->FileNameLength);
371         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
372                 FIND_FILE_STANDARD_INFO *pFindData =
373                         (FIND_FILE_STANDARD_INFO *)current_entry;
374                 filename = &pFindData->FileName[0];
375                 len = pFindData->FileNameLength;
376         } else {
377                 cFYI(1, ("Unknown findfirst level %d",
378                          cfile->srch_inf.info_level));
379         }
380
381         if (filename) {
382                 if (cfile->srch_inf.unicode) {
383                         __le16 *ufilename = (__le16 *)filename;
384                         if (len == 2) {
385                                 /* check for . */
386                                 if (ufilename[0] == UNICODE_DOT)
387                                         rc = 1;
388                         } else if (len == 4) {
389                                 /* check for .. */
390                                 if ((ufilename[0] == UNICODE_DOT)
391                                    && (ufilename[1] == UNICODE_DOT))
392                                         rc = 2;
393                         }
394                 } else /* ASCII */ {
395                         if (len == 1) {
396                                 if (filename[0] == '.')
397                                         rc = 1;
398                         } else if (len == 2) {
399                                 if ((filename[0] == '.') && (filename[1] == '.'))
400                                         rc = 2;
401                         }
402                 }
403         }
404
405         return rc;
406 }
407
408 /* Check if directory that we are searching has changed so we can decide
409    whether we can use the cached search results from the previous search */
410 static int is_dir_changed(struct file *file)
411 {
412         struct inode *inode = file->f_path.dentry->d_inode;
413         struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
414
415         if (cifsInfo->time == 0)
416                 return 1; /* directory was changed, perhaps due to unlink */
417         else
418                 return 0;
419
420 }
421
422 static int cifs_save_resume_key(const char *current_entry,
423         struct cifsFileInfo *cifsFile)
424 {
425         int rc = 0;
426         unsigned int len = 0;
427         __u16 level;
428         char *filename;
429
430         if ((cifsFile == NULL) || (current_entry == NULL))
431                 return -EINVAL;
432
433         level = cifsFile->srch_inf.info_level;
434
435         if (level == SMB_FIND_FILE_UNIX) {
436                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
437
438                 filename = &pFindData->FileName[0];
439                 if (cifsFile->srch_inf.unicode) {
440                         len = cifs_unicode_bytelen(filename);
441                 } else {
442                         /* BB should we make this strnlen of PATH_MAX? */
443                         len = strnlen(filename, PATH_MAX);
444                 }
445                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
446         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
447                 FILE_DIRECTORY_INFO *pFindData =
448                         (FILE_DIRECTORY_INFO *)current_entry;
449                 filename = &pFindData->FileName[0];
450                 len = le32_to_cpu(pFindData->FileNameLength);
451                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
452         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
453                 FILE_FULL_DIRECTORY_INFO *pFindData =
454                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
455                 filename = &pFindData->FileName[0];
456                 len = le32_to_cpu(pFindData->FileNameLength);
457                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
458         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
459                 SEARCH_ID_FULL_DIR_INFO *pFindData =
460                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
461                 filename = &pFindData->FileName[0];
462                 len = le32_to_cpu(pFindData->FileNameLength);
463                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
464         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
465                 FILE_BOTH_DIRECTORY_INFO *pFindData =
466                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
467                 filename = &pFindData->FileName[0];
468                 len = le32_to_cpu(pFindData->FileNameLength);
469                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
470         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
471                 FIND_FILE_STANDARD_INFO *pFindData =
472                         (FIND_FILE_STANDARD_INFO *)current_entry;
473                 filename = &pFindData->FileName[0];
474                 /* one byte length, no name conversion */
475                 len = (unsigned int)pFindData->FileNameLength;
476                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
477         } else {
478                 cFYI(1, ("Unknown findfirst level %d", level));
479                 return -EINVAL;
480         }
481         cifsFile->srch_inf.resume_name_len = len;
482         cifsFile->srch_inf.presume_name = filename;
483         return rc;
484 }
485
486 /* find the corresponding entry in the search */
487 /* Note that the SMB server returns search entries for . and .. which
488    complicates logic here if we choose to parse for them and we do not
489    assume that they are located in the findfirst return buffer.*/
490 /* We start counting in the buffer with entry 2 and increment for every
491    entry (do not increment for . or .. entry) */
492 static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
493         struct file *file, char **ppCurrentEntry, int *num_to_ret)
494 {
495         int rc = 0;
496         int pos_in_buf = 0;
497         loff_t first_entry_in_buffer;
498         loff_t index_to_find = file->f_pos;
499         struct cifsFileInfo *cifsFile = file->private_data;
500         /* check if index in the buffer */
501
502         if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
503            (num_to_ret == NULL))
504                 return -ENOENT;
505
506         *ppCurrentEntry = NULL;
507         first_entry_in_buffer =
508                 cifsFile->srch_inf.index_of_last_entry -
509                         cifsFile->srch_inf.entries_in_buffer;
510
511         /* if first entry in buf is zero then is first buffer
512         in search response data which means it is likely . and ..
513         will be in this buffer, although some servers do not return
514         . and .. for the root of a drive and for those we need
515         to start two entries earlier */
516
517         dump_cifs_file_struct(file, "In fce ");
518         if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
519              is_dir_changed(file)) ||
520            (index_to_find < first_entry_in_buffer)) {
521                 /* close and restart search */
522                 cFYI(1, ("search backing up - close and restart search"));
523                 write_lock(&GlobalSMBSeslock);
524                 if (!cifsFile->srch_inf.endOfSearch &&
525                     !cifsFile->invalidHandle) {
526                         cifsFile->invalidHandle = true;
527                         write_unlock(&GlobalSMBSeslock);
528                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
529                 } else
530                         write_unlock(&GlobalSMBSeslock);
531                 if (cifsFile->srch_inf.ntwrk_buf_start) {
532                         cFYI(1, ("freeing SMB ff cache buf on search rewind"));
533                         if (cifsFile->srch_inf.smallBuf)
534                                 cifs_small_buf_release(cifsFile->srch_inf.
535                                                 ntwrk_buf_start);
536                         else
537                                 cifs_buf_release(cifsFile->srch_inf.
538                                                 ntwrk_buf_start);
539                         cifsFile->srch_inf.ntwrk_buf_start = NULL;
540                 }
541                 rc = initiate_cifs_search(xid, file);
542                 if (rc) {
543                         cFYI(1, ("error %d reinitiating a search on rewind",
544                                  rc));
545                         return rc;
546                 }
547                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
548         }
549
550         while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
551               (rc == 0) && !cifsFile->srch_inf.endOfSearch) {
552                 cFYI(1, ("calling findnext2"));
553                 rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
554                                   &cifsFile->srch_inf);
555                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
556                 if (rc)
557                         return -ENOENT;
558         }
559         if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
560                 /* we found the buffer that contains the entry */
561                 /* scan and find it */
562                 int i;
563                 char *current_entry;
564                 char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
565                         smbCalcSize((struct smb_hdr *)
566                                 cifsFile->srch_inf.ntwrk_buf_start);
567
568                 current_entry = cifsFile->srch_inf.srch_entries_start;
569                 first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
570                                         - cifsFile->srch_inf.entries_in_buffer;
571                 pos_in_buf = index_to_find - first_entry_in_buffer;
572                 cFYI(1, ("found entry - pos_in_buf %d", pos_in_buf));
573
574                 for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
575                         /* go entry by entry figuring out which is first */
576                         current_entry = nxt_dir_entry(current_entry, end_of_smb,
577                                                 cifsFile->srch_inf.info_level);
578                 }
579                 if ((current_entry == NULL) && (i < pos_in_buf)) {
580                         /* BB fixme - check if we should flag this error */
581                         cERROR(1, ("reached end of buf searching for pos in buf"
582                           " %d index to find %lld rc %d",
583                           pos_in_buf, index_to_find, rc));
584                 }
585                 rc = 0;
586                 *ppCurrentEntry = current_entry;
587         } else {
588                 cFYI(1, ("index not in buffer - could not findnext into it"));
589                 return 0;
590         }
591
592         if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
593                 cFYI(1, ("can not return entries pos_in_buf beyond last"));
594                 *num_to_ret = 0;
595         } else
596                 *num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
597
598         return rc;
599 }
600
601 /* inode num, inode type and filename returned */
602 static int cifs_get_name_from_search_buf(struct qstr *pqst,
603         char *current_entry, __u16 level, unsigned int unicode,
604         struct cifs_sb_info *cifs_sb, unsigned int max_len, __u64 *pinum)
605 {
606         int rc = 0;
607         unsigned int len = 0;
608         char *filename;
609         struct nls_table *nlt = cifs_sb->local_nls;
610
611         *pinum = 0;
612
613         if (level == SMB_FIND_FILE_UNIX) {
614                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
615
616                 filename = &pFindData->FileName[0];
617                 if (unicode) {
618                         len = cifs_unicode_bytelen(filename);
619                 } else {
620                         /* BB should we make this strnlen of PATH_MAX? */
621                         len = strnlen(filename, PATH_MAX);
622                 }
623
624                 *pinum = le64_to_cpu(pFindData->basic.UniqueId);
625         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
626                 FILE_DIRECTORY_INFO *pFindData =
627                         (FILE_DIRECTORY_INFO *)current_entry;
628                 filename = &pFindData->FileName[0];
629                 len = le32_to_cpu(pFindData->FileNameLength);
630         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
631                 FILE_FULL_DIRECTORY_INFO *pFindData =
632                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
633                 filename = &pFindData->FileName[0];
634                 len = le32_to_cpu(pFindData->FileNameLength);
635         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
636                 SEARCH_ID_FULL_DIR_INFO *pFindData =
637                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
638                 filename = &pFindData->FileName[0];
639                 len = le32_to_cpu(pFindData->FileNameLength);
640                 *pinum = le64_to_cpu(pFindData->UniqueId);
641         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
642                 FILE_BOTH_DIRECTORY_INFO *pFindData =
643                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
644                 filename = &pFindData->FileName[0];
645                 len = le32_to_cpu(pFindData->FileNameLength);
646         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
647                 FIND_FILE_STANDARD_INFO *pFindData =
648                         (FIND_FILE_STANDARD_INFO *)current_entry;
649                 filename = &pFindData->FileName[0];
650                 /* one byte length, no name conversion */
651                 len = (unsigned int)pFindData->FileNameLength;
652         } else {
653                 cFYI(1, ("Unknown findfirst level %d", level));
654                 return -EINVAL;
655         }
656
657         if (len > max_len) {
658                 cERROR(1, ("bad search response length %d past smb end", len));
659                 return -EINVAL;
660         }
661
662         if (unicode) {
663                 pqst->len = cifs_from_ucs2((char *) pqst->name,
664                                            (__le16 *) filename,
665                                            UNICODE_NAME_MAX,
666                                            min(len, max_len), nlt,
667                                            cifs_sb->mnt_cifs_flags &
668                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
669         } else {
670                 pqst->name = filename;
671                 pqst->len = len;
672         }
673         pqst->hash = full_name_hash(pqst->name, pqst->len);
674 /*      cFYI(1, ("filldir on %s",pqst->name));  */
675         return rc;
676 }
677
678 static int cifs_filldir(char *pfindEntry, struct file *file, filldir_t filldir,
679                         void *direntry, char *scratch_buf, unsigned int max_len)
680 {
681         int rc = 0;
682         struct qstr qstring;
683         struct cifsFileInfo *pCifsF;
684         u64    inum;
685         ino_t  ino;
686         struct super_block *sb;
687         struct cifs_sb_info *cifs_sb;
688         struct dentry *tmp_dentry;
689         struct cifs_fattr fattr;
690
691         /* get filename and len into qstring */
692         /* get dentry */
693         /* decide whether to create and populate ionde */
694         if ((direntry == NULL) || (file == NULL))
695                 return -EINVAL;
696
697         pCifsF = file->private_data;
698
699         if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
700                 return -ENOENT;
701
702         rc = cifs_entry_is_dot(pfindEntry, pCifsF);
703         /* skip . and .. since we added them first */
704         if (rc != 0)
705                 return 0;
706
707         sb = file->f_path.dentry->d_sb;
708         cifs_sb = CIFS_SB(sb);
709
710         qstring.name = scratch_buf;
711         rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
712                         pCifsF->srch_inf.info_level,
713                         pCifsF->srch_inf.unicode, cifs_sb,
714                         max_len, &inum /* returned */);
715
716         if (rc)
717                 return rc;
718
719         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
720                 cifs_unix_basic_to_fattr(&fattr,
721                                  &((FILE_UNIX_INFO *) pfindEntry)->basic,
722                                  cifs_sb);
723         else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
724                 cifs_std_info_to_fattr(&fattr, (FIND_FILE_STANDARD_INFO *)
725                                         pfindEntry, cifs_sb);
726         else
727                 cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)
728                                         pfindEntry, cifs_sb);
729
730         /* FIXME: make _to_fattr functions fill this out */
731         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_ID_FULL_DIR_INFO)
732                 fattr.cf_uniqueid = inum;
733         else
734                 fattr.cf_uniqueid = iunique(sb, ROOT_I);
735
736         ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
737         tmp_dentry = cifs_readdir_lookup(file->f_dentry, &qstring, &fattr);
738
739         rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
740                      ino, fattr.cf_dtype);
741
742         /*
743          * we can not return filldir errors to the caller since they are
744          * "normal" when the stat blocksize is too small - we return remapped
745          * error instead
746          *
747          * FIXME: This looks bogus. filldir returns -EOVERFLOW in the above
748          * case already. Why should we be clobbering other errors from it?
749          */
750         if (rc) {
751                 cFYI(1, ("filldir rc = %d", rc));
752                 rc = -EOVERFLOW;
753         }
754         dput(tmp_dentry);
755         return rc;
756 }
757
758
759 int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
760 {
761         int rc = 0;
762         int xid, i;
763         struct cifs_sb_info *cifs_sb;
764         struct cifsTconInfo *pTcon;
765         struct cifsFileInfo *cifsFile = NULL;
766         char *current_entry;
767         int num_to_fill = 0;
768         char *tmp_buf = NULL;
769         char *end_of_smb;
770         unsigned int max_len;
771
772         xid = GetXid();
773
774         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
775         pTcon = cifs_sb->tcon;
776         if (pTcon == NULL)
777                 return -EINVAL;
778
779         switch ((int) file->f_pos) {
780         case 0:
781                 if (filldir(direntry, ".", 1, file->f_pos,
782                      file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
783                         cERROR(1, ("Filldir for current dir failed"));
784                         rc = -ENOMEM;
785                         break;
786                 }
787                 file->f_pos++;
788         case 1:
789                 if (filldir(direntry, "..", 2, file->f_pos,
790                      file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
791                         cERROR(1, ("Filldir for parent dir failed"));
792                         rc = -ENOMEM;
793                         break;
794                 }
795                 file->f_pos++;
796         default:
797                 /* 1) If search is active,
798                         is in current search buffer?
799                         if it before then restart search
800                         if after then keep searching till find it */
801
802                 if (file->private_data == NULL) {
803                         rc = initiate_cifs_search(xid, file);
804                         cFYI(1, ("initiate cifs search rc %d", rc));
805                         if (rc) {
806                                 FreeXid(xid);
807                                 return rc;
808                         }
809                 }
810                 if (file->private_data == NULL) {
811                         rc = -EINVAL;
812                         FreeXid(xid);
813                         return rc;
814                 }
815                 cifsFile = file->private_data;
816                 if (cifsFile->srch_inf.endOfSearch) {
817                         if (cifsFile->srch_inf.emptyDir) {
818                                 cFYI(1, ("End of search, empty dir"));
819                                 rc = 0;
820                                 break;
821                         }
822                 } /* else {
823                         cifsFile->invalidHandle = true;
824                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
825                 } */
826
827                 rc = find_cifs_entry(xid, pTcon, file,
828                                 &current_entry, &num_to_fill);
829                 if (rc) {
830                         cFYI(1, ("fce error %d", rc));
831                         goto rddir2_exit;
832                 } else if (current_entry != NULL) {
833                         cFYI(1, ("entry %lld found", file->f_pos));
834                 } else {
835                         cFYI(1, ("could not find entry"));
836                         goto rddir2_exit;
837                 }
838                 cFYI(1, ("loop through %d times filling dir for net buf %p",
839                         num_to_fill, cifsFile->srch_inf.ntwrk_buf_start));
840                 max_len = smbCalcSize((struct smb_hdr *)
841                                 cifsFile->srch_inf.ntwrk_buf_start);
842                 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
843
844                 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
845                 for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
846                         if (current_entry == NULL) {
847                                 /* evaluate whether this case is an error */
848                                 cERROR(1, ("past SMB end,  num to fill %d i %d",
849                                           num_to_fill, i));
850                                 break;
851                         }
852                         /* if buggy server returns . and .. late do
853                         we want to check for that here? */
854                         rc = cifs_filldir(current_entry, file,
855                                         filldir, direntry, tmp_buf, max_len);
856                         if (rc == -EOVERFLOW) {
857                                 rc = 0;
858                                 break;
859                         }
860
861                         file->f_pos++;
862                         if (file->f_pos ==
863                                 cifsFile->srch_inf.index_of_last_entry) {
864                                 cFYI(1, ("last entry in buf at pos %lld %s",
865                                         file->f_pos, tmp_buf));
866                                 cifs_save_resume_key(current_entry, cifsFile);
867                                 break;
868                         } else
869                                 current_entry =
870                                         nxt_dir_entry(current_entry, end_of_smb,
871                                                 cifsFile->srch_inf.info_level);
872                 }
873                 kfree(tmp_buf);
874                 break;
875         } /* end switch */
876
877 rddir2_exit:
878         FreeXid(xid);
879         return rc;
880 }