1 /*
2 * fs/cifs/readdir.c
3 *
4 * Directory search handling
5 *
6 * Copyright (C) International Business Machines Corp., 2004, 2008
7 * Copyright (C) Red Hat, Inc., 2011
8 * Author(s): Steve French (sfrench@us.ibm.com)
9 *
10 * This library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published
12 * by the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
14 *
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
18 * the GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this library; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24 #include <linux/fs.h>
25 #include <linux/pagemap.h>
26 #include <linux/slab.h>
27 #include <linux/stat.h>
28 #include "cifspdu.h"
29 #include "cifsglob.h"
30 #include "cifsproto.h"
31 #include "cifs_unicode.h"
32 #include "cifs_debug.h"
33 #include "cifs_fs_sb.h"
34 #include "cifsfs.h"
35
36 /*
37 * To be safe - for UCS to UTF-8 with strings loaded with the rare long
38 * characters alloc more to account for such multibyte target UTF-8
39 * characters.
40 */
41 #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
42
43 #ifdef CONFIG_CIFS_DEBUG2
44 static void dump_cifs_file_struct(struct file *file, char *label)
45 {
46 struct cifsFileInfo *cf;
47
48 if (file) {
49 cf = file->private_data;
50 if (cf == NULL) {
51 cifs_dbg(FYI, "empty cifs private file data\n");
52 return;
53 }
54 if (cf->invalidHandle)
55 cifs_dbg(FYI, "invalid handle\n");
56 if (cf->srch_inf.endOfSearch)
57 cifs_dbg(FYI, "end of search\n");
58 if (cf->srch_inf.emptyDir)
59 cifs_dbg(FYI, "empty dir\n");
60 }
61 }
62 #else
63 static inline void dump_cifs_file_struct(struct file *file, char *label)
64 {
65 }
66 #endif /* DEBUG2 */
67
68 /*
69 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT
70 *
71 * Find the dentry that matches "name". If there isn't one, create one. If it's
72 * a negative dentry or the uniqueid or filetype(mode) changed,
73 * then drop it and recreate it.
74 */
75 static void
76 cifs_prime_dcache(struct dentry *parent, struct qstr *name,
77 struct cifs_fattr *fattr)
78 {
79 struct dentry *dentry, *alias;
80 struct inode *inode;
81 struct super_block *sb = parent->d_sb;
82 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
83 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
84
85 cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
86
87 dentry = d_hash_and_lookup(parent, name);
88 if (!dentry) {
89 /*
90 * If we know that the inode will need to be revalidated
91 * immediately, then don't create a new dentry for it.
92 * We'll end up doing an on the wire call either way and
93 * this spares us an invalidation.
94 */
95 if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
96 return;
97 retry:
98 dentry = d_alloc_parallel(parent, name, &wq);
99 }
100 if (IS_ERR(dentry))
101 return;
102 if (!d_in_lookup(dentry)) {
103 inode = d_inode(dentry);
104 if (inode) {
105 if (d_mountpoint(dentry)) {
106 dput(dentry);
107 return;
108 }
109 /*
110 * If we're generating inode numbers, then we don't
111 * want to clobber the existing one with the one that
112 * the readdir code created.
113 */
114 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
115 fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
116
117 /* update inode in place
118 * if both i_ino and i_mode didn't change */
119 if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid &&
120 (inode->i_mode & S_IFMT) ==
121 (fattr->cf_mode & S_IFMT)) {
122 cifs_fattr_to_inode(inode, fattr);
123 dput(dentry);
124 return;
125 }
126 }
127 d_invalidate(dentry);
128 dput(dentry);
129 goto retry;
130 } else {
131 inode = cifs_iget(sb, fattr);
132 if (!inode)
133 inode = ERR_PTR(-ENOMEM);
134 alias = d_splice_alias(inode, dentry);
135 d_lookup_done(dentry);
136 if (alias && !IS_ERR(alias))
137 dput(alias);
138 }
139 dput(dentry);
140 }
141
142 static void
143 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
144 {
145 fattr->cf_uid = cifs_sb->mnt_uid;
146 fattr->cf_gid = cifs_sb->mnt_gid;
147
148 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
149 fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
150 fattr->cf_dtype = DT_DIR;
151 } else {
152 fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
153 fattr->cf_dtype = DT_REG;
154 }
155
156 /*
157 * We need to revalidate it further to make a decision about whether it
158 * is a symbolic link, DFS referral or a reparse point with a direct
159 * access like junctions, deduplicated files, NFS symlinks.
160 */
161 if (fattr->cf_cifsattrs & ATTR_REPARSE)
162 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
163
164 /* non-unix readdir doesn't provide nlink */
165 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
166
167 if (fattr->cf_cifsattrs & ATTR_READONLY)
168 fattr->cf_mode &= ~S_IWUGO;
169
170 /*
171 * We of course don't get ACL info in FIND_FIRST/NEXT results, so
172 * mark it for revalidation so that "ls -l" will look right. It might
173 * be super-slow, but if we don't do this then the ownership of files
174 * may look wrong since the inodes may not have timed out by the time
175 * "ls" does a stat() call on them.
176 */
177 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL)
178 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
179
180 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
181 fattr->cf_cifsattrs & ATTR_SYSTEM) {
182 if (fattr->cf_eof == 0) {
183 fattr->cf_mode &= ~S_IFMT;
184 fattr->cf_mode |= S_IFIFO;
185 fattr->cf_dtype = DT_FIFO;
186 } else {
187 /*
188 * trying to get the type and mode via SFU can be slow,
189 * so just call those regular files for now, and mark
190 * for reval
191 */
192 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
193 }
194 }
195 }
196
197 void
198 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
199 struct cifs_sb_info *cifs_sb)
200 {
201 memset(fattr, 0, sizeof(*fattr));
202 fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
203 fattr->cf_eof = le64_to_cpu(info->EndOfFile);
204 fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
205 fattr->cf_createtime = le64_to_cpu(info->CreationTime);
206 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
207 fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
208 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
209
210 cifs_fill_common_info(fattr, cifs_sb);
211 }
212
213 static void
214 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
215 struct cifs_sb_info *cifs_sb)
216 {
217 int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
218
219 memset(fattr, 0, sizeof(*fattr));
220 fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
221 info->LastAccessTime, offset);
222 fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
223 info->LastWriteTime, offset);
224 fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
225 info->LastWriteTime, offset);
226
227 fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
228 fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
229 fattr->cf_eof = le32_to_cpu(info->DataSize);
230
231 cifs_fill_common_info(fattr, cifs_sb);
232 }
233
234 /* BB eventually need to add the following helper function to
235 resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
236 we try to do FindFirst on (NTFS) directory symlinks */
237 /*
238 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
239 unsigned int xid)
240 {
241 __u16 fid;
242 int len;
243 int oplock = 0;
244 int rc;
245 struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
246 char *tmpbuffer;
247
248 rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
249 OPEN_REPARSE_POINT, &fid, &oplock, NULL,
250 cifs_sb->local_nls,
251 cifs_remap(cifs_sb);
252 if (!rc) {
253 tmpbuffer = kmalloc(maxpath);
254 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
255 tmpbuffer,
256 maxpath -1,
257 fid,
258 cifs_sb->local_nls);
259 if (CIFSSMBClose(xid, ptcon, fid)) {
260 cifs_dbg(FYI, "Error closing temporary reparsepoint open\n");
261 }
262 }
263 }
264 */
265
266 static int
267 initiate_cifs_search(const unsigned int xid, struct file *file)
268 {
269 __u16 search_flags;
270 int rc = 0;
271 char *full_path = NULL;
272 struct cifsFileInfo *cifsFile;
273 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
274 struct tcon_link *tlink = NULL;
275 struct cifs_tcon *tcon;
276 struct TCP_Server_Info *server;
277
278 if (file->private_data == NULL) {
279 tlink = cifs_sb_tlink(cifs_sb);
280 if (IS_ERR(tlink))
281 return PTR_ERR(tlink);
282
283 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
284 if (cifsFile == NULL) {
285 rc = -ENOMEM;
286 goto error_exit;
287 }
288 spin_lock_init(&cifsFile->file_info_lock);
289 file->private_data = cifsFile;
290 cifsFile->tlink = cifs_get_tlink(tlink);
291 tcon = tlink_tcon(tlink);
292 } else {
293 cifsFile = file->private_data;
294 tcon = tlink_tcon(cifsFile->tlink);
295 }
296
297 server = tcon->ses->server;
298
299 if (!server->ops->query_dir_first) {
300 rc = -ENOSYS;
301 goto error_exit;
302 }
303
304 cifsFile->invalidHandle = true;
305 cifsFile->srch_inf.endOfSearch = false;
306
307 full_path = build_path_from_dentry(file_dentry(file));
308 if (full_path == NULL) {
309 rc = -ENOMEM;
310 goto error_exit;
311 }
312
313 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);
314
315 ffirst_retry:
316 /* test for Unix extensions */
317 /* but now check for them on the share/mount not on the SMB session */
318 /* if (cap_unix(tcon->ses) { */
319 if (tcon->unix_ext)
320 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
321 else if ((tcon->ses->capabilities &
322 tcon->ses->server->vals->cap_nt_find) == 0) {
323 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
324 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
325 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
326 } else /* not srvinos - BB fixme add check for backlevel? */ {
327 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
328 }
329
330 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
331 if (backup_cred(cifs_sb))
332 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
333
334 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,
335 &cifsFile->fid, search_flags,
336 &cifsFile->srch_inf);
337
338 if (rc == 0)
339 cifsFile->invalidHandle = false;
340 /* BB add following call to handle readdir on new NTFS symlink errors
341 else if STATUS_STOPPED_ON_SYMLINK
342 call get_symlink_reparse_path and retry with new path */
343 else if ((rc == -EOPNOTSUPP) &&
344 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
345 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
346 goto ffirst_retry;
347 }
348 error_exit:
349 kfree(full_path);
350 cifs_put_tlink(tlink);
351 return rc;
352 }
353
354 /* return length of unicode string in bytes */
355 static int cifs_unicode_bytelen(const char *str)
356 {
357 int len;
358 const __le16 *ustr = (const __le16 *)str;
359
360 for (len = 0; len <= PATH_MAX; len++) {
361 if (ustr[len] == 0)
362 return len << 1;
363 }
364 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");
365 return len << 1;
366 }
367
368 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
369 {
370 char *new_entry;
371 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
372
373 if (level == SMB_FIND_FILE_INFO_STANDARD) {
374 FIND_FILE_STANDARD_INFO *pfData;
375 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
376
377 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
378 pfData->FileNameLength;
379 } else {
380 u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset);
381
382 if (old_entry + next_offset < old_entry) {
383 cifs_dbg(VFS, "invalid offset %u\n", next_offset);
384 return NULL;
385 }
386 new_entry = old_entry + next_offset;
387 }
388 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
389 /* validate that new_entry is not past end of SMB */
390 if (new_entry >= end_of_smb) {
391 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",
392 new_entry, end_of_smb, old_entry);
393 return NULL;
394 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
395 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
396 || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
397 (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb))) {
398 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",
399 new_entry, end_of_smb);
400 return NULL;
401 } else
402 return new_entry;
403
404 }
405
406 struct cifs_dirent {
407 const char *name;
408 size_t namelen;
409 u32 resume_key;
410 u64 ino;
411 };
412
413 static void cifs_fill_dirent_unix(struct cifs_dirent *de,
414 const FILE_UNIX_INFO *info, bool is_unicode)
415 {
416 de->name = &info->FileName[0];
417 if (is_unicode)
418 de->namelen = cifs_unicode_bytelen(de->name);
419 else
420 de->namelen = strnlen(de->name, PATH_MAX);
421 de->resume_key = info->ResumeKey;
422 de->ino = le64_to_cpu(info->basic.UniqueId);
423 }
424
425 static void cifs_fill_dirent_dir(struct cifs_dirent *de,
426 const FILE_DIRECTORY_INFO *info)
427 {
428 de->name = &info->FileName[0];
429 de->namelen = le32_to_cpu(info->FileNameLength);
430 de->resume_key = info->FileIndex;
431 }
432
433 static void cifs_fill_dirent_full(struct cifs_dirent *de,
434 const FILE_FULL_DIRECTORY_INFO *info)
435 {
436 de->name = &info->FileName[0];
437 de->namelen = le32_to_cpu(info->FileNameLength);
438 de->resume_key = info->FileIndex;
439 }
440
441 static void cifs_fill_dirent_search(struct cifs_dirent *de,
442 const SEARCH_ID_FULL_DIR_INFO *info)
443 {
444 de->name = &info->FileName[0];
445 de->namelen = le32_to_cpu(info->FileNameLength);
446 de->resume_key = info->FileIndex;
447 de->ino = le64_to_cpu(info->UniqueId);
448 }
449
450 static void cifs_fill_dirent_both(struct cifs_dirent *de,
451 const FILE_BOTH_DIRECTORY_INFO *info)
452 {
453 de->name = &info->FileName[0];
454 de->namelen = le32_to_cpu(info->FileNameLength);
455 de->resume_key = info->FileIndex;
456 }
457
458 static void cifs_fill_dirent_std(struct cifs_dirent *de,
459 const FIND_FILE_STANDARD_INFO *info)
460 {
461 de->name = &info->FileName[0];
462 /* one byte length, no endianess conversion */
463 de->namelen = info->FileNameLength;
464 de->resume_key = info->ResumeKey;
465 }
466
467 static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
468 u16 level, bool is_unicode)
469 {
470 memset(de, 0, sizeof(*de));
471
472 switch (level) {
473 case SMB_FIND_FILE_UNIX:
474 cifs_fill_dirent_unix(de, info, is_unicode);
475 break;
476 case SMB_FIND_FILE_DIRECTORY_INFO:
477 cifs_fill_dirent_dir(de, info);
478 break;
479 case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
480 cifs_fill_dirent_full(de, info);
481 break;
482 case SMB_FIND_FILE_ID_FULL_DIR_INFO:
483 cifs_fill_dirent_search(de, info);
484 break;
485 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
486 cifs_fill_dirent_both(de, info);
487 break;
488 case SMB_FIND_FILE_INFO_STANDARD:
489 cifs_fill_dirent_std(de, info);
490 break;
491 default:
492 cifs_dbg(FYI, "Unknown findfirst level %d\n", level);
493 return -EINVAL;
494 }
495
496 return 0;
497 }
498
499 #define UNICODE_DOT cpu_to_le16(0x2e)
500
501 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
502 static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
503 {
504 int rc = 0;
505
506 if (!de->name)
507 return 0;
508
509 if (is_unicode) {
510 __le16 *ufilename = (__le16 *)de->name;
511 if (de->namelen == 2) {
512 /* check for . */
513 if (ufilename[0] == UNICODE_DOT)
514 rc = 1;
515 } else if (de->namelen == 4) {
516 /* check for .. */
517 if (ufilename[0] == UNICODE_DOT &&
518 ufilename[1] == UNICODE_DOT)
519 rc = 2;
520 }
521 } else /* ASCII */ {
522 if (de->namelen == 1) {
523 if (de->name[0] == '.')
524 rc = 1;
525 } else if (de->namelen == 2) {
526 if (de->name[0] == '.' && de->name[1] == '.')
527 rc = 2;
528 }
529 }
530
531 return rc;
532 }
533
534 /* Check if directory that we are searching has changed so we can decide
535 whether we can use the cached search results from the previous search */
536 static int is_dir_changed(struct file *file)
537 {
538 struct inode *inode = file_inode(file);
539 struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
540
541 if (cifsInfo->time == 0)
542 return 1; /* directory was changed, perhaps due to unlink */
543 else
544 return 0;
545
546 }
547
548 static int cifs_save_resume_key(const char *current_entry,
549 struct cifsFileInfo *file_info)
550 {
551 struct cifs_dirent de;
552 int rc;
553
554 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
555 file_info->srch_inf.unicode);
556 if (!rc) {
557 file_info->srch_inf.presume_name = de.name;
558 file_info->srch_inf.resume_name_len = de.namelen;
559 file_info->srch_inf.resume_key = de.resume_key;
560 }
561 return rc;
562 }
563
564 /*
565 * Find the corresponding entry in the search. Note that the SMB server returns
566 * search entries for . and .. which complicates logic here if we choose to
567 * parse for them and we do not assume that they are located in the findfirst
568 * return buffer. We start counting in the buffer with entry 2 and increment for
569 * every entry (do not increment for . or .. entry).
570 */
571 static int
572 find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
573 struct file *file, char **current_entry, int *num_to_ret)
574 {
575 __u16 search_flags;
576 int rc = 0;
577 int pos_in_buf = 0;
578 loff_t first_entry_in_buffer;
579 loff_t index_to_find = pos;
580 struct cifsFileInfo *cfile = file->private_data;
581 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
582 struct TCP_Server_Info *server = tcon->ses->server;
583 /* check if index in the buffer */
584
585 if (!server->ops->query_dir_first || !server->ops->query_dir_next)
586 return -ENOSYS;
587
588 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))
589 return -ENOENT;
590
591 *current_entry = NULL;
592 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
593 cfile->srch_inf.entries_in_buffer;
594
595 /*
596 * If first entry in buf is zero then is first buffer
597 * in search response data which means it is likely . and ..
598 * will be in this buffer, although some servers do not return
599 * . and .. for the root of a drive and for those we need
600 * to start two entries earlier.
601 */
602
603 dump_cifs_file_struct(file, "In fce ");
604 if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&
605 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {
606 /* close and restart search */
607 cifs_dbg(FYI, "search backing up - close and restart search\n");
608 spin_lock(&cfile->file_info_lock);
609 if (server->ops->dir_needs_close(cfile)) {
610 cfile->invalidHandle = true;
611 spin_unlock(&cfile->file_info_lock);
612 if (server->ops->close_dir)
613 server->ops->close_dir(xid, tcon, &cfile->fid);
614 } else
615 spin_unlock(&cfile->file_info_lock);
616 if (cfile->srch_inf.ntwrk_buf_start) {
617 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");
618 if (cfile->srch_inf.smallBuf)
619 cifs_small_buf_release(cfile->srch_inf.
620 ntwrk_buf_start);
621 else
622 cifs_buf_release(cfile->srch_inf.
623 ntwrk_buf_start);
624 cfile->srch_inf.ntwrk_buf_start = NULL;
625 }
626 rc = initiate_cifs_search(xid, file);
627 if (rc) {
628 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",
629 rc);
630 return rc;
631 }
632 /* FindFirst/Next set last_entry to NULL on malformed reply */
633 if (cfile->srch_inf.last_entry)
634 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
635 }
636
637 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
638 if (backup_cred(cifs_sb))
639 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
640
641 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&
642 (rc == 0) && !cfile->srch_inf.endOfSearch) {
643 cifs_dbg(FYI, "calling findnext2\n");
644 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,
645 search_flags,
646 &cfile->srch_inf);
647 /* FindFirst/Next set last_entry to NULL on malformed reply */
648 if (cfile->srch_inf.last_entry)
649 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
650 if (rc)
651 return -ENOENT;
652 }
653 if (index_to_find < cfile->srch_inf.index_of_last_entry) {
654 /* we found the buffer that contains the entry */
655 /* scan and find it */
656 int i;
657 char *cur_ent;
658 char *end_of_smb;
659
660 if (cfile->srch_inf.ntwrk_buf_start == NULL) {
661 cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n");
662 return -EIO;
663 }
664
665 end_of_smb = cfile->srch_inf.ntwrk_buf_start +
666 server->ops->calc_smb_size(
667 cfile->srch_inf.ntwrk_buf_start,
668 server);
669
670 cur_ent = cfile->srch_inf.srch_entries_start;
671 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
672 - cfile->srch_inf.entries_in_buffer;
673 pos_in_buf = index_to_find - first_entry_in_buffer;
674 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);
675
676 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
677 /* go entry by entry figuring out which is first */
678 cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
679 cfile->srch_inf.info_level);
680 }
681 if ((cur_ent == NULL) && (i < pos_in_buf)) {
682 /* BB fixme - check if we should flag this error */
683 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",
684 pos_in_buf, index_to_find, rc);
685 }
686 rc = 0;
687 *current_entry = cur_ent;
688 } else {
689 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");
690 return 0;
691 }
692
693 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {
694 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");
695 *num_to_ret = 0;
696 } else
697 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;
698
699 return rc;
700 }
701
702 static int cifs_filldir(char *find_entry, struct file *file,
703 struct dir_context *ctx,
704 char *scratch_buf, unsigned int max_len)
705 {
706 struct cifsFileInfo *file_info = file->private_data;
707 struct super_block *sb = file_inode(file)->i_sb;
708 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
709 struct cifs_dirent de = { NULL, };
710 struct cifs_fattr fattr;
711 struct qstr name;
712 int rc = 0;
713 ino_t ino;
714
715 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
716 file_info->srch_inf.unicode);
717 if (rc)
718 return rc;
719
720 if (de.namelen > max_len) {
721 cifs_dbg(VFS, "bad search response length %zd past smb end\n",
722 de.namelen);
723 return -EINVAL;
724 }
725
726 /* skip . and .. since we added them first */
727 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
728 return 0;
729
730 if (file_info->srch_inf.unicode) {
731 struct nls_table *nlt = cifs_sb->local_nls;
732 int map_type;
733
734 map_type = cifs_remap(cifs_sb);
735 name.name = scratch_buf;
736 name.len =
737 cifs_from_utf16((char *)name.name, (__le16 *)de.name,
738 UNICODE_NAME_MAX,
739 min_t(size_t, de.namelen,
740 (size_t)max_len), nlt, map_type);
741 name.len -= nls_nullsize(nlt);
742 } else {
743 name.name = de.name;
744 name.len = de.namelen;
745 }
746
747 switch (file_info->srch_inf.info_level) {
748 case SMB_FIND_FILE_UNIX:
749 cifs_unix_basic_to_fattr(&fattr,
750 &((FILE_UNIX_INFO *)find_entry)->basic,
751 cifs_sb);
752 break;
753 case SMB_FIND_FILE_INFO_STANDARD:
754 cifs_std_info_to_fattr(&fattr,
755 (FIND_FILE_STANDARD_INFO *)find_entry,
756 cifs_sb);
757 break;
758 default:
759 cifs_dir_info_to_fattr(&fattr,
760 (FILE_DIRECTORY_INFO *)find_entry,
761 cifs_sb);
762 break;
763 }
764
765 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
766 fattr.cf_uniqueid = de.ino;
767 } else {
768 fattr.cf_uniqueid = iunique(sb, ROOT_I);
769 cifs_autodisable_serverino(cifs_sb);
770 }
771
772 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
773 couldbe_mf_symlink(&fattr))
774 /*
775 * trying to get the type and mode can be slow,
776 * so just call those regular files for now, and mark
777 * for reval
778 */
779 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
780
781 cifs_prime_dcache(file_dentry(file), &name, &fattr);
782
783 ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
784 return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);
785 }
786
787
788 int cifs_readdir(struct file *file, struct dir_context *ctx)
789 {
790 int rc = 0;
791 unsigned int xid;
792 int i;
793 struct cifs_tcon *tcon;
794 struct cifsFileInfo *cifsFile = NULL;
795 char *current_entry;
796 int num_to_fill = 0;
797 char *tmp_buf = NULL;
798 char *end_of_smb;
799 unsigned int max_len;
800
801 xid = get_xid();
802
803 /*
804 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
805 * '..'. Otherwise we won't be able to notify VFS in case of failure.
806 */
807 if (file->private_data == NULL) {
808 rc = initiate_cifs_search(xid, file);
809 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
810 if (rc)
811 goto rddir2_exit;
812 }
813
814 if (!dir_emit_dots(file, ctx))
815 goto rddir2_exit;
816
817 /* 1) If search is active,
818 is in current search buffer?
819 if it before then restart search
820 if after then keep searching till find it */
821
822 cifsFile = file->private_data;
823 if (cifsFile->srch_inf.endOfSearch) {
824 if (cifsFile->srch_inf.emptyDir) {
825 cifs_dbg(FYI, "End of search, empty dir\n");
826 rc = 0;
827 goto rddir2_exit;
828 }
829 } /* else {
830 cifsFile->invalidHandle = true;
831 tcon->ses->server->close(xid, tcon, &cifsFile->fid);
832 } */
833
834 tcon = tlink_tcon(cifsFile->tlink);
835 rc = find_cifs_entry(xid, tcon, ctx->pos, file, ¤t_entry,
836 &num_to_fill);
837 if (rc) {
838 cifs_dbg(FYI, "fce error %d\n", rc);
839 goto rddir2_exit;
840 } else if (current_entry != NULL) {
841 cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
842 } else {
843 cifs_dbg(FYI, "could not find entry\n");
844 goto rddir2_exit;
845 }
846 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
847 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
848 max_len = tcon->ses->server->ops->calc_smb_size(
849 cifsFile->srch_inf.ntwrk_buf_start,
850 tcon->ses->server);
851 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
852
853 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
854 if (tmp_buf == NULL) {
855 rc = -ENOMEM;
856 goto rddir2_exit;
857 }
858
859 for (i = 0; i < num_to_fill; i++) {
860 if (current_entry == NULL) {
861 /* evaluate whether this case is an error */
862 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n",
863 num_to_fill, i);
864 break;
865 }
866 /*
867 * if buggy server returns . and .. late do we want to
868 * check for that here?
869 */
870 *tmp_buf = 0;
871 rc = cifs_filldir(current_entry, file, ctx,
872 tmp_buf, max_len);
873 if (rc) {
874 if (rc > 0)
875 rc = 0;
876 break;
877 }
878
879 ctx->pos++;
880 if (ctx->pos ==
881 cifsFile->srch_inf.index_of_last_entry) {
882 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
883 ctx->pos, tmp_buf);
884 cifs_save_resume_key(current_entry, cifsFile);
885 break;
886 } else
887 current_entry =
888 nxt_dir_entry(current_entry, end_of_smb,
889 cifsFile->srch_inf.info_level);
890 }
891 kfree(tmp_buf);
892
893 rddir2_exit:
894 free_xid(xid);
895 return rc;
896 }
897
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