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v4.6
  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
 44static 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
 63static 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 */
 75static void
 76cifs_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 = d_inode(parent)->i_sb;
 82	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
 
 83
 84	cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
 85
 86	dentry = d_hash_and_lookup(parent, name);
 
 
 
 
 
 
 
 
 
 
 
 
 87	if (IS_ERR(dentry))
 88		return;
 89
 90	if (dentry) {
 91		inode = d_inode(dentry);
 92		if (inode) {
 93			if (d_mountpoint(dentry))
 94				goto out;
 
 
 95			/*
 96			 * If we're generating inode numbers, then we don't
 97			 * want to clobber the existing one with the one that
 98			 * the readdir code created.
 99			 */
100			if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
101				fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
102
103			/* update inode in place
104			 * if both i_ino and i_mode didn't change */
105			if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid &&
106			    (inode->i_mode & S_IFMT) ==
107			    (fattr->cf_mode & S_IFMT)) {
108				cifs_fattr_to_inode(inode, fattr);
109				goto out;
 
110			}
111		}
112		d_invalidate(dentry);
113		dput(dentry);
 
 
 
 
 
 
 
 
 
114	}
 
 
115
 
 
 
 
116	/*
117	 * If we know that the inode will need to be revalidated immediately,
118	 * then don't create a new dentry for it. We'll end up doing an on
119	 * the wire call either way and this spares us an invalidation.
 
 
120	 */
121	if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
122		return;
123
124	dentry = d_alloc(parent, name);
125	if (!dentry)
126		return;
127
128	inode = cifs_iget(sb, fattr);
129	if (!inode)
130		goto out;
131
132	alias = d_splice_alias(inode, dentry);
133	if (alias && !IS_ERR(alias))
134		dput(alias);
135out:
136	dput(dentry);
137}
138
139static void
140cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
141{
142	fattr->cf_uid = cifs_sb->mnt_uid;
143	fattr->cf_gid = cifs_sb->mnt_gid;
144
145	if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
146		fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
147		fattr->cf_dtype = DT_DIR;
148	} else {
149		fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
150		fattr->cf_dtype = DT_REG;
151	}
152
153	/*
154	 * We need to revalidate it further to make a decision about whether it
155	 * is a symbolic link, DFS referral or a reparse point with a direct
156	 * access like junctions, deduplicated files, NFS symlinks.
157	 */
158	if (fattr->cf_cifsattrs & ATTR_REPARSE)
159		fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
160
161	/* non-unix readdir doesn't provide nlink */
162	fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
163
164	if (fattr->cf_cifsattrs & ATTR_READONLY)
165		fattr->cf_mode &= ~S_IWUGO;
166
167	/*
168	 * We of course don't get ACL info in FIND_FIRST/NEXT results, so
169	 * mark it for revalidation so that "ls -l" will look right. It might
170	 * be super-slow, but if we don't do this then the ownership of files
171	 * may look wrong since the inodes may not have timed out by the time
172	 * "ls" does a stat() call on them.
173	 */
174	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL)
 
175		fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
176
177	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
178	    fattr->cf_cifsattrs & ATTR_SYSTEM) {
179		if (fattr->cf_eof == 0)  {
180			fattr->cf_mode &= ~S_IFMT;
181			fattr->cf_mode |= S_IFIFO;
182			fattr->cf_dtype = DT_FIFO;
183		} else {
184			/*
185			 * trying to get the type and mode via SFU can be slow,
186			 * so just call those regular files for now, and mark
187			 * for reval
188			 */
189			fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
190		}
191	}
192}
193
194void
195cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
196		       struct cifs_sb_info *cifs_sb)
 
197{
 
 
 
 
198	memset(fattr, 0, sizeof(*fattr));
199	fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
200	fattr->cf_eof = le64_to_cpu(info->EndOfFile);
201	fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
202	fattr->cf_createtime = le64_to_cpu(info->CreationTime);
 
203	fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
204	fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
205	fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
 
 
 
 
 
 
 
 
 
 
 
206
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
207	cifs_fill_common_info(fattr, cifs_sb);
208}
209
210static void
211cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
212		       struct cifs_sb_info *cifs_sb)
213{
214	int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
215
216	memset(fattr, 0, sizeof(*fattr));
217	fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
218					    info->LastAccessTime, offset);
219	fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
220					    info->LastWriteTime, offset);
221	fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
222					    info->LastWriteTime, offset);
223
224	fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
225	fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
226	fattr->cf_eof = le32_to_cpu(info->DataSize);
227
228	cifs_fill_common_info(fattr, cifs_sb);
229}
230
231/* BB eventually need to add the following helper function to
232      resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
233      we try to do FindFirst on (NTFS) directory symlinks */
234/*
235int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
236			     unsigned int xid)
237{
238	__u16 fid;
239	int len;
240	int oplock = 0;
241	int rc;
242	struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
243	char *tmpbuffer;
244
245	rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
246			OPEN_REPARSE_POINT, &fid, &oplock, NULL,
247			cifs_sb->local_nls,
248			cifs_remap(cifs_sb);
249	if (!rc) {
250		tmpbuffer = kmalloc(maxpath);
251		rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
252				tmpbuffer,
253				maxpath -1,
254				fid,
255				cifs_sb->local_nls);
256		if (CIFSSMBClose(xid, ptcon, fid)) {
257			cifs_dbg(FYI, "Error closing temporary reparsepoint open\n");
258		}
259	}
260}
261 */
262
263static int
264initiate_cifs_search(const unsigned int xid, struct file *file)
265{
266	__u16 search_flags;
267	int rc = 0;
268	char *full_path = NULL;
269	struct cifsFileInfo *cifsFile;
270	struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
271	struct tcon_link *tlink = NULL;
272	struct cifs_tcon *tcon;
273	struct TCP_Server_Info *server;
274
275	if (file->private_data == NULL) {
276		tlink = cifs_sb_tlink(cifs_sb);
277		if (IS_ERR(tlink))
278			return PTR_ERR(tlink);
279
280		cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
281		if (cifsFile == NULL) {
282			rc = -ENOMEM;
283			goto error_exit;
284		}
 
285		file->private_data = cifsFile;
286		cifsFile->tlink = cifs_get_tlink(tlink);
287		tcon = tlink_tcon(tlink);
288	} else {
289		cifsFile = file->private_data;
290		tcon = tlink_tcon(cifsFile->tlink);
291	}
292
293	server = tcon->ses->server;
294
295	if (!server->ops->query_dir_first) {
296		rc = -ENOSYS;
297		goto error_exit;
298	}
299
300	cifsFile->invalidHandle = true;
301	cifsFile->srch_inf.endOfSearch = false;
302
303	full_path = build_path_from_dentry(file->f_path.dentry);
304	if (full_path == NULL) {
305		rc = -ENOMEM;
306		goto error_exit;
307	}
308
309	cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);
310
311ffirst_retry:
312	/* test for Unix extensions */
313	/* but now check for them on the share/mount not on the SMB session */
314	/* if (cap_unix(tcon->ses) { */
315	if (tcon->unix_ext)
316		cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
 
 
317	else if ((tcon->ses->capabilities &
318		  tcon->ses->server->vals->cap_nt_find) == 0) {
319		cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
320	} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
321		cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
322	} else /* not srvinos - BB fixme add check for backlevel? */ {
323		cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
324	}
325
326	search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
327	if (backup_cred(cifs_sb))
328		search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
329
330	rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,
331					  &cifsFile->fid, search_flags,
332					  &cifsFile->srch_inf);
333
334	if (rc == 0)
335		cifsFile->invalidHandle = false;
336	/* BB add following call to handle readdir on new NTFS symlink errors
337	else if STATUS_STOPPED_ON_SYMLINK
338		call get_symlink_reparse_path and retry with new path */
339	else if ((rc == -EOPNOTSUPP) &&
340		(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
341		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
342		goto ffirst_retry;
343	}
344error_exit:
345	kfree(full_path);
346	cifs_put_tlink(tlink);
347	return rc;
348}
349
350/* return length of unicode string in bytes */
351static int cifs_unicode_bytelen(const char *str)
352{
353	int len;
354	const __le16 *ustr = (const __le16 *)str;
355
356	for (len = 0; len <= PATH_MAX; len++) {
357		if (ustr[len] == 0)
358			return len << 1;
359	}
360	cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");
361	return len << 1;
362}
363
364static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
365{
366	char *new_entry;
367	FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
368
369	if (level == SMB_FIND_FILE_INFO_STANDARD) {
370		FIND_FILE_STANDARD_INFO *pfData;
371		pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
372
373		new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
374				pfData->FileNameLength;
375	} else
376		new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
 
 
 
 
 
 
 
377	cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
378	/* validate that new_entry is not past end of SMB */
379	if (new_entry >= end_of_smb) {
380		cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",
381			 new_entry, end_of_smb, old_entry);
382		return NULL;
383	} else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
384		    (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
385		  || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
386		   (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
387		cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",
388			 new_entry, end_of_smb);
389		return NULL;
390	} else
391		return new_entry;
392
393}
394
395struct cifs_dirent {
396	const char	*name;
397	size_t		namelen;
398	u32		resume_key;
399	u64		ino;
400};
401
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
402static void cifs_fill_dirent_unix(struct cifs_dirent *de,
403		const FILE_UNIX_INFO *info, bool is_unicode)
404{
405	de->name = &info->FileName[0];
406	if (is_unicode)
407		de->namelen = cifs_unicode_bytelen(de->name);
408	else
409		de->namelen = strnlen(de->name, PATH_MAX);
410	de->resume_key = info->ResumeKey;
411	de->ino = le64_to_cpu(info->basic.UniqueId);
412}
413
414static void cifs_fill_dirent_dir(struct cifs_dirent *de,
415		const FILE_DIRECTORY_INFO *info)
416{
417	de->name = &info->FileName[0];
418	de->namelen = le32_to_cpu(info->FileNameLength);
419	de->resume_key = info->FileIndex;
420}
421
422static void cifs_fill_dirent_full(struct cifs_dirent *de,
423		const FILE_FULL_DIRECTORY_INFO *info)
424{
425	de->name = &info->FileName[0];
426	de->namelen = le32_to_cpu(info->FileNameLength);
427	de->resume_key = info->FileIndex;
428}
429
430static void cifs_fill_dirent_search(struct cifs_dirent *de,
431		const SEARCH_ID_FULL_DIR_INFO *info)
432{
433	de->name = &info->FileName[0];
434	de->namelen = le32_to_cpu(info->FileNameLength);
435	de->resume_key = info->FileIndex;
436	de->ino = le64_to_cpu(info->UniqueId);
437}
438
439static void cifs_fill_dirent_both(struct cifs_dirent *de,
440		const FILE_BOTH_DIRECTORY_INFO *info)
441{
442	de->name = &info->FileName[0];
443	de->namelen = le32_to_cpu(info->FileNameLength);
444	de->resume_key = info->FileIndex;
445}
446
447static void cifs_fill_dirent_std(struct cifs_dirent *de,
448		const FIND_FILE_STANDARD_INFO *info)
449{
450	de->name = &info->FileName[0];
451	/* one byte length, no endianess conversion */
452	de->namelen = info->FileNameLength;
453	de->resume_key = info->ResumeKey;
454}
455
456static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
457		u16 level, bool is_unicode)
458{
459	memset(de, 0, sizeof(*de));
460
461	switch (level) {
 
 
 
462	case SMB_FIND_FILE_UNIX:
463		cifs_fill_dirent_unix(de, info, is_unicode);
464		break;
465	case SMB_FIND_FILE_DIRECTORY_INFO:
466		cifs_fill_dirent_dir(de, info);
467		break;
468	case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
469		cifs_fill_dirent_full(de, info);
470		break;
471	case SMB_FIND_FILE_ID_FULL_DIR_INFO:
472		cifs_fill_dirent_search(de, info);
473		break;
474	case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
475		cifs_fill_dirent_both(de, info);
476		break;
477	case SMB_FIND_FILE_INFO_STANDARD:
478		cifs_fill_dirent_std(de, info);
479		break;
480	default:
481		cifs_dbg(FYI, "Unknown findfirst level %d\n", level);
482		return -EINVAL;
483	}
484
485	return 0;
486}
487
488#define UNICODE_DOT cpu_to_le16(0x2e)
489
490/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
491static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
492{
493	int rc = 0;
494
495	if (!de->name)
496		return 0;
497
498	if (is_unicode) {
499		__le16 *ufilename = (__le16 *)de->name;
500		if (de->namelen == 2) {
501			/* check for . */
502			if (ufilename[0] == UNICODE_DOT)
503				rc = 1;
504		} else if (de->namelen == 4) {
505			/* check for .. */
506			if (ufilename[0] == UNICODE_DOT &&
507			    ufilename[1] == UNICODE_DOT)
508				rc = 2;
509		}
510	} else /* ASCII */ {
511		if (de->namelen == 1) {
512			if (de->name[0] == '.')
513				rc = 1;
514		} else if (de->namelen == 2) {
515			if (de->name[0] == '.' && de->name[1] == '.')
516				rc = 2;
517		}
518	}
519
520	return rc;
521}
522
523/* Check if directory that we are searching has changed so we can decide
524   whether we can use the cached search results from the previous search */
525static int is_dir_changed(struct file *file)
526{
527	struct inode *inode = file_inode(file);
528	struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
529
530	if (cifsInfo->time == 0)
531		return 1; /* directory was changed, perhaps due to unlink */
532	else
533		return 0;
534
535}
536
537static int cifs_save_resume_key(const char *current_entry,
538	struct cifsFileInfo *file_info)
539{
540	struct cifs_dirent de;
541	int rc;
542
543	rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
544			      file_info->srch_inf.unicode);
545	if (!rc) {
546		file_info->srch_inf.presume_name = de.name;
547		file_info->srch_inf.resume_name_len = de.namelen;
548		file_info->srch_inf.resume_key = de.resume_key;
549	}
550	return rc;
551}
552
553/*
554 * Find the corresponding entry in the search. Note that the SMB server returns
555 * search entries for . and .. which complicates logic here if we choose to
556 * parse for them and we do not assume that they are located in the findfirst
557 * return buffer. We start counting in the buffer with entry 2 and increment for
558 * every entry (do not increment for . or .. entry).
559 */
560static int
561find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
562		struct file *file, char **current_entry, int *num_to_ret)
563{
564	__u16 search_flags;
565	int rc = 0;
566	int pos_in_buf = 0;
567	loff_t first_entry_in_buffer;
568	loff_t index_to_find = pos;
569	struct cifsFileInfo *cfile = file->private_data;
570	struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
571	struct TCP_Server_Info *server = tcon->ses->server;
572	/* check if index in the buffer */
573
574	if (!server->ops->query_dir_first || !server->ops->query_dir_next)
575		return -ENOSYS;
576
577	if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))
578		return -ENOENT;
579
580	*current_entry = NULL;
581	first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
582					cfile->srch_inf.entries_in_buffer;
583
584	/*
585	 * If first entry in buf is zero then is first buffer
586	 * in search response data which means it is likely . and ..
587	 * will be in this buffer, although some servers do not return
588	 * . and .. for the root of a drive and for those we need
589	 * to start two entries earlier.
590	 */
591
592	dump_cifs_file_struct(file, "In fce ");
593	if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&
594	     is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {
595		/* close and restart search */
596		cifs_dbg(FYI, "search backing up - close and restart search\n");
597		spin_lock(&cifs_file_list_lock);
598		if (server->ops->dir_needs_close(cfile)) {
599			cfile->invalidHandle = true;
600			spin_unlock(&cifs_file_list_lock);
601			if (server->ops->close_dir)
602				server->ops->close_dir(xid, tcon, &cfile->fid);
603		} else
604			spin_unlock(&cifs_file_list_lock);
605		if (cfile->srch_inf.ntwrk_buf_start) {
606			cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");
607			if (cfile->srch_inf.smallBuf)
608				cifs_small_buf_release(cfile->srch_inf.
609						ntwrk_buf_start);
610			else
611				cifs_buf_release(cfile->srch_inf.
612						ntwrk_buf_start);
613			cfile->srch_inf.ntwrk_buf_start = NULL;
614		}
615		rc = initiate_cifs_search(xid, file);
616		if (rc) {
617			cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",
618				 rc);
619			return rc;
620		}
621		/* FindFirst/Next set last_entry to NULL on malformed reply */
622		if (cfile->srch_inf.last_entry)
623			cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
624	}
625
626	search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
627	if (backup_cred(cifs_sb))
628		search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
629
630	while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&
631	       (rc == 0) && !cfile->srch_inf.endOfSearch) {
632		cifs_dbg(FYI, "calling findnext2\n");
633		rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,
634						 search_flags,
635						 &cfile->srch_inf);
636		/* FindFirst/Next set last_entry to NULL on malformed reply */
637		if (cfile->srch_inf.last_entry)
638			cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
639		if (rc)
640			return -ENOENT;
641	}
642	if (index_to_find < cfile->srch_inf.index_of_last_entry) {
643		/* we found the buffer that contains the entry */
644		/* scan and find it */
645		int i;
646		char *cur_ent;
647		char *end_of_smb = cfile->srch_inf.ntwrk_buf_start +
 
 
 
 
 
 
 
648			server->ops->calc_smb_size(
649					cfile->srch_inf.ntwrk_buf_start);
 
650
651		cur_ent = cfile->srch_inf.srch_entries_start;
652		first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
653					- cfile->srch_inf.entries_in_buffer;
654		pos_in_buf = index_to_find - first_entry_in_buffer;
655		cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);
656
657		for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
658			/* go entry by entry figuring out which is first */
659			cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
660						cfile->srch_inf.info_level);
661		}
662		if ((cur_ent == NULL) && (i < pos_in_buf)) {
663			/* BB fixme - check if we should flag this error */
664			cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",
665				 pos_in_buf, index_to_find, rc);
666		}
667		rc = 0;
668		*current_entry = cur_ent;
669	} else {
670		cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");
671		return 0;
672	}
673
674	if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {
675		cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");
676		*num_to_ret = 0;
677	} else
678		*num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;
679
680	return rc;
681}
682
683static int cifs_filldir(char *find_entry, struct file *file,
684		struct dir_context *ctx,
685		char *scratch_buf, unsigned int max_len)
686{
687	struct cifsFileInfo *file_info = file->private_data;
688	struct super_block *sb = file_inode(file)->i_sb;
689	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
690	struct cifs_dirent de = { NULL, };
691	struct cifs_fattr fattr;
692	struct qstr name;
693	int rc = 0;
694	ino_t ino;
695
696	rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
697			      file_info->srch_inf.unicode);
698	if (rc)
699		return rc;
700
701	if (de.namelen > max_len) {
702		cifs_dbg(VFS, "bad search response length %zd past smb end\n",
703			 de.namelen);
704		return -EINVAL;
705	}
706
707	/* skip . and .. since we added them first */
708	if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
709		return 0;
710
711	if (file_info->srch_inf.unicode) {
712		struct nls_table *nlt = cifs_sb->local_nls;
713		int map_type;
714
715		map_type = cifs_remap(cifs_sb);
716		name.name = scratch_buf;
717		name.len =
718			cifs_from_utf16((char *)name.name, (__le16 *)de.name,
719					UNICODE_NAME_MAX,
720					min_t(size_t, de.namelen,
721					      (size_t)max_len), nlt, map_type);
722		name.len -= nls_nullsize(nlt);
723	} else {
724		name.name = de.name;
725		name.len = de.namelen;
726	}
727
728	switch (file_info->srch_inf.info_level) {
 
 
 
 
 
729	case SMB_FIND_FILE_UNIX:
730		cifs_unix_basic_to_fattr(&fattr,
731					 &((FILE_UNIX_INFO *)find_entry)->basic,
732					 cifs_sb);
733		break;
734	case SMB_FIND_FILE_INFO_STANDARD:
735		cifs_std_info_to_fattr(&fattr,
736				       (FIND_FILE_STANDARD_INFO *)find_entry,
737				       cifs_sb);
738		break;
 
 
 
 
 
739	default:
740		cifs_dir_info_to_fattr(&fattr,
741				       (FILE_DIRECTORY_INFO *)find_entry,
742				       cifs_sb);
743		break;
744	}
745
746	if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
747		fattr.cf_uniqueid = de.ino;
748	} else {
749		fattr.cf_uniqueid = iunique(sb, ROOT_I);
750		cifs_autodisable_serverino(cifs_sb);
751	}
752
753	if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
754	    couldbe_mf_symlink(&fattr))
755		/*
756		 * trying to get the type and mode can be slow,
757		 * so just call those regular files for now, and mark
758		 * for reval
759		 */
760		fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
761
762	cifs_prime_dcache(file->f_path.dentry, &name, &fattr);
763
764	ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
765	return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);
766}
767
768
769int cifs_readdir(struct file *file, struct dir_context *ctx)
770{
771	int rc = 0;
772	unsigned int xid;
773	int i;
774	struct cifs_tcon *tcon;
775	struct cifsFileInfo *cifsFile = NULL;
776	char *current_entry;
777	int num_to_fill = 0;
778	char *tmp_buf = NULL;
779	char *end_of_smb;
780	unsigned int max_len;
781
782	xid = get_xid();
783
784	/*
785	 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
786	 * '..'. Otherwise we won't be able to notify VFS in case of failure.
787	 */
788	if (file->private_data == NULL) {
789		rc = initiate_cifs_search(xid, file);
790		cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
791		if (rc)
792			goto rddir2_exit;
793	}
794
795	if (!dir_emit_dots(file, ctx))
796		goto rddir2_exit;
797
798	/* 1) If search is active,
799		is in current search buffer?
800		if it before then restart search
801		if after then keep searching till find it */
802
803	cifsFile = file->private_data;
804	if (cifsFile->srch_inf.endOfSearch) {
805		if (cifsFile->srch_inf.emptyDir) {
806			cifs_dbg(FYI, "End of search, empty dir\n");
807			rc = 0;
808			goto rddir2_exit;
809		}
810	} /* else {
811		cifsFile->invalidHandle = true;
812		tcon->ses->server->close(xid, tcon, &cifsFile->fid);
813	} */
814
815	tcon = tlink_tcon(cifsFile->tlink);
816	rc = find_cifs_entry(xid, tcon, ctx->pos, file, &current_entry,
817			     &num_to_fill);
818	if (rc) {
819		cifs_dbg(FYI, "fce error %d\n", rc);
820		goto rddir2_exit;
821	} else if (current_entry != NULL) {
822		cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
823	} else {
824		cifs_dbg(FYI, "could not find entry\n");
825		goto rddir2_exit;
826	}
827	cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
828		 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
829	max_len = tcon->ses->server->ops->calc_smb_size(
830			cifsFile->srch_inf.ntwrk_buf_start);
 
831	end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
832
833	tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
834	if (tmp_buf == NULL) {
835		rc = -ENOMEM;
836		goto rddir2_exit;
837	}
838
839	for (i = 0; i < num_to_fill; i++) {
840		if (current_entry == NULL) {
841			/* evaluate whether this case is an error */
842			cifs_dbg(VFS, "past SMB end,  num to fill %d i %d\n",
843				 num_to_fill, i);
844			break;
845		}
846		/*
847		 * if buggy server returns . and .. late do we want to
848		 * check for that here?
849		 */
850		*tmp_buf = 0;
851		rc = cifs_filldir(current_entry, file, ctx,
852				  tmp_buf, max_len);
853		if (rc) {
854			if (rc > 0)
855				rc = 0;
856			break;
857		}
858
859		ctx->pos++;
860		if (ctx->pos ==
861			cifsFile->srch_inf.index_of_last_entry) {
862			cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
863				 ctx->pos, tmp_buf);
864			cifs_save_resume_key(current_entry, cifsFile);
865			break;
866		} else
867			current_entry =
868				nxt_dir_entry(current_entry, end_of_smb,
869					cifsFile->srch_inf.info_level);
870	}
871	kfree(tmp_buf);
872
873rddir2_exit:
874	free_xid(xid);
875	return rc;
876}
v5.9
   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#include "smb2proto.h"
  36
  37/*
  38 * To be safe - for UCS to UTF-8 with strings loaded with the rare long
  39 * characters alloc more to account for such multibyte target UTF-8
  40 * characters.
  41 */
  42#define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
  43
  44#ifdef CONFIG_CIFS_DEBUG2
  45static void dump_cifs_file_struct(struct file *file, char *label)
  46{
  47	struct cifsFileInfo *cf;
  48
  49	if (file) {
  50		cf = file->private_data;
  51		if (cf == NULL) {
  52			cifs_dbg(FYI, "empty cifs private file data\n");
  53			return;
  54		}
  55		if (cf->invalidHandle)
  56			cifs_dbg(FYI, "Invalid handle\n");
  57		if (cf->srch_inf.endOfSearch)
  58			cifs_dbg(FYI, "end of search\n");
  59		if (cf->srch_inf.emptyDir)
  60			cifs_dbg(FYI, "empty dir\n");
  61	}
  62}
  63#else
  64static inline void dump_cifs_file_struct(struct file *file, char *label)
  65{
  66}
  67#endif /* DEBUG2 */
  68
  69/*
  70 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT
  71 *
  72 * Find the dentry that matches "name". If there isn't one, create one. If it's
  73 * a negative dentry or the uniqueid or filetype(mode) changed,
  74 * then drop it and recreate it.
  75 */
  76static void
  77cifs_prime_dcache(struct dentry *parent, struct qstr *name,
  78		    struct cifs_fattr *fattr)
  79{
  80	struct dentry *dentry, *alias;
  81	struct inode *inode;
  82	struct super_block *sb = parent->d_sb;
  83	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
  84	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
  85
  86	cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
  87
  88	dentry = d_hash_and_lookup(parent, name);
  89	if (!dentry) {
  90		/*
  91		 * If we know that the inode will need to be revalidated
  92		 * immediately, then don't create a new dentry for it.
  93		 * We'll end up doing an on the wire call either way and
  94		 * this spares us an invalidation.
  95		 */
  96		if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
  97			return;
  98retry:
  99		dentry = d_alloc_parallel(parent, name, &wq);
 100	}
 101	if (IS_ERR(dentry))
 102		return;
 103	if (!d_in_lookup(dentry)) {
 
 104		inode = d_inode(dentry);
 105		if (inode) {
 106			if (d_mountpoint(dentry)) {
 107				dput(dentry);
 108				return;
 109			}
 110			/*
 111			 * If we're generating inode numbers, then we don't
 112			 * want to clobber the existing one with the one that
 113			 * the readdir code created.
 114			 */
 115			if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
 116				fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
 117
 118			/* update inode in place
 119			 * if both i_ino and i_mode didn't change */
 120			if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid &&
 121			    (inode->i_mode & S_IFMT) ==
 122			    (fattr->cf_mode & S_IFMT)) {
 123				cifs_fattr_to_inode(inode, fattr);
 124				dput(dentry);
 125				return;
 126			}
 127		}
 128		d_invalidate(dentry);
 129		dput(dentry);
 130		goto retry;
 131	} else {
 132		inode = cifs_iget(sb, fattr);
 133		if (!inode)
 134			inode = ERR_PTR(-ENOMEM);
 135		alias = d_splice_alias(inode, dentry);
 136		d_lookup_done(dentry);
 137		if (alias && !IS_ERR(alias))
 138			dput(alias);
 139	}
 140	dput(dentry);
 141}
 142
 143static bool reparse_file_needs_reval(const struct cifs_fattr *fattr)
 144{
 145	if (!(fattr->cf_cifsattrs & ATTR_REPARSE))
 146		return false;
 147	/*
 148	 * The DFS tags should be only intepreted by server side as per
 149	 * MS-FSCC 2.1.2.1, but let's include them anyway.
 150	 *
 151	 * Besides, if cf_cifstag is unset (0), then we still need it to be
 152	 * revalidated to know exactly what reparse point it is.
 153	 */
 154	switch (fattr->cf_cifstag) {
 155	case IO_REPARSE_TAG_DFS:
 156	case IO_REPARSE_TAG_DFSR:
 157	case IO_REPARSE_TAG_SYMLINK:
 158	case IO_REPARSE_TAG_NFS:
 159	case 0:
 160		return true;
 161	}
 162	return false;
 
 
 
 
 
 
 
 163}
 164
 165static void
 166cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
 167{
 168	fattr->cf_uid = cifs_sb->mnt_uid;
 169	fattr->cf_gid = cifs_sb->mnt_gid;
 170
 171	if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
 172		fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
 173		fattr->cf_dtype = DT_DIR;
 174	} else {
 175		fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
 176		fattr->cf_dtype = DT_REG;
 177	}
 178
 179	/*
 180	 * We need to revalidate it further to make a decision about whether it
 181	 * is a symbolic link, DFS referral or a reparse point with a direct
 182	 * access like junctions, deduplicated files, NFS symlinks.
 183	 */
 184	if (reparse_file_needs_reval(fattr))
 185		fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
 186
 187	/* non-unix readdir doesn't provide nlink */
 188	fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
 189
 190	if (fattr->cf_cifsattrs & ATTR_READONLY)
 191		fattr->cf_mode &= ~S_IWUGO;
 192
 193	/*
 194	 * We of course don't get ACL info in FIND_FIRST/NEXT results, so
 195	 * mark it for revalidation so that "ls -l" will look right. It might
 196	 * be super-slow, but if we don't do this then the ownership of files
 197	 * may look wrong since the inodes may not have timed out by the time
 198	 * "ls" does a stat() call on them.
 199	 */
 200	if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) ||
 201	    (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID))
 202		fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
 203
 204	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
 205	    fattr->cf_cifsattrs & ATTR_SYSTEM) {
 206		if (fattr->cf_eof == 0)  {
 207			fattr->cf_mode &= ~S_IFMT;
 208			fattr->cf_mode |= S_IFIFO;
 209			fattr->cf_dtype = DT_FIFO;
 210		} else {
 211			/*
 212			 * trying to get the type and mode via SFU can be slow,
 213			 * so just call those regular files for now, and mark
 214			 * for reval
 215			 */
 216			fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
 217		}
 218	}
 219}
 220
 221/* Fill a cifs_fattr struct with info from SMB_FIND_FILE_POSIX_INFO. */
 222static void
 223cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info,
 224		    struct cifs_sb_info *cifs_sb)
 225{
 226	struct smb2_posix_info_parsed parsed;
 227
 228	posix_info_parse(info, NULL, &parsed);
 229
 230	memset(fattr, 0, sizeof(*fattr));
 231	fattr->cf_uniqueid = le64_to_cpu(info->Inode);
 
 232	fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
 233	fattr->cf_eof = le64_to_cpu(info->EndOfFile);
 234
 235	fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
 
 236	fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
 237	fattr->cf_ctime = cifs_NTtimeToUnix(info->CreationTime);
 238
 239	fattr->cf_nlink = le32_to_cpu(info->HardLinks);
 240	fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes);
 241
 242	/*
 243	 * Since we set the inode type below we need to mask off
 244	 * to avoid strange results if bits set above.
 245	 * XXX: why not make server&client use the type bits?
 246	 */
 247	fattr->cf_mode = le32_to_cpu(info->Mode) & ~S_IFMT;
 248
 249	cifs_dbg(FYI, "posix fattr: dev %d, reparse %d, mode %o\n",
 250		 le32_to_cpu(info->DeviceId),
 251		 le32_to_cpu(info->ReparseTag),
 252		 le32_to_cpu(info->Mode));
 253
 254	if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
 255		fattr->cf_mode |= S_IFDIR;
 256		fattr->cf_dtype = DT_DIR;
 257	} else {
 258		/*
 259		 * mark anything that is not a dir as regular
 260		 * file. special files should have the REPARSE
 261		 * attribute and will be marked as needing revaluation
 262		 */
 263		fattr->cf_mode |= S_IFREG;
 264		fattr->cf_dtype = DT_REG;
 265	}
 266
 267	if (reparse_file_needs_reval(fattr))
 268		fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
 269
 270	/* TODO map SIDs */
 271	fattr->cf_uid = cifs_sb->mnt_uid;
 272	fattr->cf_gid = cifs_sb->mnt_gid;
 273}
 274
 275static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info)
 276{
 277	const FILE_DIRECTORY_INFO *fi = info;
 278
 279	memset(fattr, 0, sizeof(*fattr));
 280	fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes);
 281	fattr->cf_eof = le64_to_cpu(fi->EndOfFile);
 282	fattr->cf_bytes = le64_to_cpu(fi->AllocationSize);
 283	fattr->cf_createtime = le64_to_cpu(fi->CreationTime);
 284	fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime);
 285	fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime);
 286	fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime);
 287}
 288
 289void
 290cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
 291		       struct cifs_sb_info *cifs_sb)
 292{
 293	__dir_info_to_fattr(fattr, info);
 294	cifs_fill_common_info(fattr, cifs_sb);
 295}
 296
 297static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr,
 298				       SEARCH_ID_FULL_DIR_INFO *info,
 299				       struct cifs_sb_info *cifs_sb)
 300{
 301	__dir_info_to_fattr(fattr, info);
 302
 303	/* See MS-FSCC 2.4.18 FileIdFullDirectoryInformation */
 304	if (fattr->cf_cifsattrs & ATTR_REPARSE)
 305		fattr->cf_cifstag = le32_to_cpu(info->EaSize);
 306	cifs_fill_common_info(fattr, cifs_sb);
 307}
 308
 309static void
 310cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
 311		       struct cifs_sb_info *cifs_sb)
 312{
 313	int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
 314
 315	memset(fattr, 0, sizeof(*fattr));
 316	fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
 317					    info->LastAccessTime, offset);
 318	fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
 319					    info->LastWriteTime, offset);
 320	fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
 321					    info->LastWriteTime, offset);
 322
 323	fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
 324	fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
 325	fattr->cf_eof = le32_to_cpu(info->DataSize);
 326
 327	cifs_fill_common_info(fattr, cifs_sb);
 328}
 329
 330/* BB eventually need to add the following helper function to
 331      resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
 332      we try to do FindFirst on (NTFS) directory symlinks */
 333/*
 334int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
 335			     unsigned int xid)
 336{
 337	__u16 fid;
 338	int len;
 339	int oplock = 0;
 340	int rc;
 341	struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
 342	char *tmpbuffer;
 343
 344	rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
 345			OPEN_REPARSE_POINT, &fid, &oplock, NULL,
 346			cifs_sb->local_nls,
 347			cifs_remap(cifs_sb);
 348	if (!rc) {
 349		tmpbuffer = kmalloc(maxpath);
 350		rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
 351				tmpbuffer,
 352				maxpath -1,
 353				fid,
 354				cifs_sb->local_nls);
 355		if (CIFSSMBClose(xid, ptcon, fid)) {
 356			cifs_dbg(FYI, "Error closing temporary reparsepoint open\n");
 357		}
 358	}
 359}
 360 */
 361
 362static int
 363initiate_cifs_search(const unsigned int xid, struct file *file)
 364{
 365	__u16 search_flags;
 366	int rc = 0;
 367	char *full_path = NULL;
 368	struct cifsFileInfo *cifsFile;
 369	struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
 370	struct tcon_link *tlink = NULL;
 371	struct cifs_tcon *tcon;
 372	struct TCP_Server_Info *server;
 373
 374	if (file->private_data == NULL) {
 375		tlink = cifs_sb_tlink(cifs_sb);
 376		if (IS_ERR(tlink))
 377			return PTR_ERR(tlink);
 378
 379		cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
 380		if (cifsFile == NULL) {
 381			rc = -ENOMEM;
 382			goto error_exit;
 383		}
 384		spin_lock_init(&cifsFile->file_info_lock);
 385		file->private_data = cifsFile;
 386		cifsFile->tlink = cifs_get_tlink(tlink);
 387		tcon = tlink_tcon(tlink);
 388	} else {
 389		cifsFile = file->private_data;
 390		tcon = tlink_tcon(cifsFile->tlink);
 391	}
 392
 393	server = tcon->ses->server;
 394
 395	if (!server->ops->query_dir_first) {
 396		rc = -ENOSYS;
 397		goto error_exit;
 398	}
 399
 400	cifsFile->invalidHandle = true;
 401	cifsFile->srch_inf.endOfSearch = false;
 402
 403	full_path = build_path_from_dentry(file_dentry(file));
 404	if (full_path == NULL) {
 405		rc = -ENOMEM;
 406		goto error_exit;
 407	}
 408
 409	cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);
 410
 411ffirst_retry:
 412	/* test for Unix extensions */
 413	/* but now check for them on the share/mount not on the SMB session */
 414	/* if (cap_unix(tcon->ses) { */
 415	if (tcon->unix_ext)
 416		cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
 417	else if (tcon->posix_extensions)
 418		cifsFile->srch_inf.info_level = SMB_FIND_FILE_POSIX_INFO;
 419	else if ((tcon->ses->capabilities &
 420		  tcon->ses->server->vals->cap_nt_find) == 0) {
 421		cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
 422	} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
 423		cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
 424	} else /* not srvinos - BB fixme add check for backlevel? */ {
 425		cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
 426	}
 427
 428	search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
 429	if (backup_cred(cifs_sb))
 430		search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
 431
 432	rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,
 433					  &cifsFile->fid, search_flags,
 434					  &cifsFile->srch_inf);
 435
 436	if (rc == 0)
 437		cifsFile->invalidHandle = false;
 438	/* BB add following call to handle readdir on new NTFS symlink errors
 439	else if STATUS_STOPPED_ON_SYMLINK
 440		call get_symlink_reparse_path and retry with new path */
 441	else if ((rc == -EOPNOTSUPP) &&
 442		(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 443		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
 444		goto ffirst_retry;
 445	}
 446error_exit:
 447	kfree(full_path);
 448	cifs_put_tlink(tlink);
 449	return rc;
 450}
 451
 452/* return length of unicode string in bytes */
 453static int cifs_unicode_bytelen(const char *str)
 454{
 455	int len;
 456	const __le16 *ustr = (const __le16 *)str;
 457
 458	for (len = 0; len <= PATH_MAX; len++) {
 459		if (ustr[len] == 0)
 460			return len << 1;
 461	}
 462	cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");
 463	return len << 1;
 464}
 465
 466static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
 467{
 468	char *new_entry;
 469	FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
 470
 471	if (level == SMB_FIND_FILE_INFO_STANDARD) {
 472		FIND_FILE_STANDARD_INFO *pfData;
 473		pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
 474
 475		new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
 476				pfData->FileNameLength;
 477	} else {
 478		u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset);
 479
 480		if (old_entry + next_offset < old_entry) {
 481			cifs_dbg(VFS, "Invalid offset %u\n", next_offset);
 482			return NULL;
 483		}
 484		new_entry = old_entry + next_offset;
 485	}
 486	cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
 487	/* validate that new_entry is not past end of SMB */
 488	if (new_entry >= end_of_smb) {
 489		cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",
 490			 new_entry, end_of_smb, old_entry);
 491		return NULL;
 492	} else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
 493		    (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
 494		  || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
 495		   (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
 496		cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",
 497			 new_entry, end_of_smb);
 498		return NULL;
 499	} else
 500		return new_entry;
 501
 502}
 503
 504struct cifs_dirent {
 505	const char	*name;
 506	size_t		namelen;
 507	u32		resume_key;
 508	u64		ino;
 509};
 510
 511static void cifs_fill_dirent_posix(struct cifs_dirent *de,
 512				   const struct smb2_posix_info *info)
 513{
 514	struct smb2_posix_info_parsed parsed;
 515
 516	/* payload should have already been checked at this point */
 517	if (posix_info_parse(info, NULL, &parsed) < 0) {
 518		cifs_dbg(VFS, "Invalid POSIX info payload\n");
 519		return;
 520	}
 521
 522	de->name = parsed.name;
 523	de->namelen = parsed.name_len;
 524	de->resume_key = info->Ignored;
 525	de->ino = le64_to_cpu(info->Inode);
 526}
 527
 528static void cifs_fill_dirent_unix(struct cifs_dirent *de,
 529		const FILE_UNIX_INFO *info, bool is_unicode)
 530{
 531	de->name = &info->FileName[0];
 532	if (is_unicode)
 533		de->namelen = cifs_unicode_bytelen(de->name);
 534	else
 535		de->namelen = strnlen(de->name, PATH_MAX);
 536	de->resume_key = info->ResumeKey;
 537	de->ino = le64_to_cpu(info->basic.UniqueId);
 538}
 539
 540static void cifs_fill_dirent_dir(struct cifs_dirent *de,
 541		const FILE_DIRECTORY_INFO *info)
 542{
 543	de->name = &info->FileName[0];
 544	de->namelen = le32_to_cpu(info->FileNameLength);
 545	de->resume_key = info->FileIndex;
 546}
 547
 548static void cifs_fill_dirent_full(struct cifs_dirent *de,
 549		const FILE_FULL_DIRECTORY_INFO *info)
 550{
 551	de->name = &info->FileName[0];
 552	de->namelen = le32_to_cpu(info->FileNameLength);
 553	de->resume_key = info->FileIndex;
 554}
 555
 556static void cifs_fill_dirent_search(struct cifs_dirent *de,
 557		const SEARCH_ID_FULL_DIR_INFO *info)
 558{
 559	de->name = &info->FileName[0];
 560	de->namelen = le32_to_cpu(info->FileNameLength);
 561	de->resume_key = info->FileIndex;
 562	de->ino = le64_to_cpu(info->UniqueId);
 563}
 564
 565static void cifs_fill_dirent_both(struct cifs_dirent *de,
 566		const FILE_BOTH_DIRECTORY_INFO *info)
 567{
 568	de->name = &info->FileName[0];
 569	de->namelen = le32_to_cpu(info->FileNameLength);
 570	de->resume_key = info->FileIndex;
 571}
 572
 573static void cifs_fill_dirent_std(struct cifs_dirent *de,
 574		const FIND_FILE_STANDARD_INFO *info)
 575{
 576	de->name = &info->FileName[0];
 577	/* one byte length, no endianess conversion */
 578	de->namelen = info->FileNameLength;
 579	de->resume_key = info->ResumeKey;
 580}
 581
 582static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
 583		u16 level, bool is_unicode)
 584{
 585	memset(de, 0, sizeof(*de));
 586
 587	switch (level) {
 588	case SMB_FIND_FILE_POSIX_INFO:
 589		cifs_fill_dirent_posix(de, info);
 590		break;
 591	case SMB_FIND_FILE_UNIX:
 592		cifs_fill_dirent_unix(de, info, is_unicode);
 593		break;
 594	case SMB_FIND_FILE_DIRECTORY_INFO:
 595		cifs_fill_dirent_dir(de, info);
 596		break;
 597	case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
 598		cifs_fill_dirent_full(de, info);
 599		break;
 600	case SMB_FIND_FILE_ID_FULL_DIR_INFO:
 601		cifs_fill_dirent_search(de, info);
 602		break;
 603	case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
 604		cifs_fill_dirent_both(de, info);
 605		break;
 606	case SMB_FIND_FILE_INFO_STANDARD:
 607		cifs_fill_dirent_std(de, info);
 608		break;
 609	default:
 610		cifs_dbg(FYI, "Unknown findfirst level %d\n", level);
 611		return -EINVAL;
 612	}
 613
 614	return 0;
 615}
 616
 617#define UNICODE_DOT cpu_to_le16(0x2e)
 618
 619/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
 620static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
 621{
 622	int rc = 0;
 623
 624	if (!de->name)
 625		return 0;
 626
 627	if (is_unicode) {
 628		__le16 *ufilename = (__le16 *)de->name;
 629		if (de->namelen == 2) {
 630			/* check for . */
 631			if (ufilename[0] == UNICODE_DOT)
 632				rc = 1;
 633		} else if (de->namelen == 4) {
 634			/* check for .. */
 635			if (ufilename[0] == UNICODE_DOT &&
 636			    ufilename[1] == UNICODE_DOT)
 637				rc = 2;
 638		}
 639	} else /* ASCII */ {
 640		if (de->namelen == 1) {
 641			if (de->name[0] == '.')
 642				rc = 1;
 643		} else if (de->namelen == 2) {
 644			if (de->name[0] == '.' && de->name[1] == '.')
 645				rc = 2;
 646		}
 647	}
 648
 649	return rc;
 650}
 651
 652/* Check if directory that we are searching has changed so we can decide
 653   whether we can use the cached search results from the previous search */
 654static int is_dir_changed(struct file *file)
 655{
 656	struct inode *inode = file_inode(file);
 657	struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
 658
 659	if (cifsInfo->time == 0)
 660		return 1; /* directory was changed, perhaps due to unlink */
 661	else
 662		return 0;
 663
 664}
 665
 666static int cifs_save_resume_key(const char *current_entry,
 667	struct cifsFileInfo *file_info)
 668{
 669	struct cifs_dirent de;
 670	int rc;
 671
 672	rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
 673			      file_info->srch_inf.unicode);
 674	if (!rc) {
 675		file_info->srch_inf.presume_name = de.name;
 676		file_info->srch_inf.resume_name_len = de.namelen;
 677		file_info->srch_inf.resume_key = de.resume_key;
 678	}
 679	return rc;
 680}
 681
 682/*
 683 * Find the corresponding entry in the search. Note that the SMB server returns
 684 * search entries for . and .. which complicates logic here if we choose to
 685 * parse for them and we do not assume that they are located in the findfirst
 686 * return buffer. We start counting in the buffer with entry 2 and increment for
 687 * every entry (do not increment for . or .. entry).
 688 */
 689static int
 690find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
 691		struct file *file, char **current_entry, int *num_to_ret)
 692{
 693	__u16 search_flags;
 694	int rc = 0;
 695	int pos_in_buf = 0;
 696	loff_t first_entry_in_buffer;
 697	loff_t index_to_find = pos;
 698	struct cifsFileInfo *cfile = file->private_data;
 699	struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
 700	struct TCP_Server_Info *server = tcon->ses->server;
 701	/* check if index in the buffer */
 702
 703	if (!server->ops->query_dir_first || !server->ops->query_dir_next)
 704		return -ENOSYS;
 705
 706	if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))
 707		return -ENOENT;
 708
 709	*current_entry = NULL;
 710	first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
 711					cfile->srch_inf.entries_in_buffer;
 712
 713	/*
 714	 * If first entry in buf is zero then is first buffer
 715	 * in search response data which means it is likely . and ..
 716	 * will be in this buffer, although some servers do not return
 717	 * . and .. for the root of a drive and for those we need
 718	 * to start two entries earlier.
 719	 */
 720
 721	dump_cifs_file_struct(file, "In fce ");
 722	if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&
 723	     is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {
 724		/* close and restart search */
 725		cifs_dbg(FYI, "search backing up - close and restart search\n");
 726		spin_lock(&cfile->file_info_lock);
 727		if (server->ops->dir_needs_close(cfile)) {
 728			cfile->invalidHandle = true;
 729			spin_unlock(&cfile->file_info_lock);
 730			if (server->ops->close_dir)
 731				server->ops->close_dir(xid, tcon, &cfile->fid);
 732		} else
 733			spin_unlock(&cfile->file_info_lock);
 734		if (cfile->srch_inf.ntwrk_buf_start) {
 735			cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");
 736			if (cfile->srch_inf.smallBuf)
 737				cifs_small_buf_release(cfile->srch_inf.
 738						ntwrk_buf_start);
 739			else
 740				cifs_buf_release(cfile->srch_inf.
 741						ntwrk_buf_start);
 742			cfile->srch_inf.ntwrk_buf_start = NULL;
 743		}
 744		rc = initiate_cifs_search(xid, file);
 745		if (rc) {
 746			cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",
 747				 rc);
 748			return rc;
 749		}
 750		/* FindFirst/Next set last_entry to NULL on malformed reply */
 751		if (cfile->srch_inf.last_entry)
 752			cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
 753	}
 754
 755	search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
 756	if (backup_cred(cifs_sb))
 757		search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
 758
 759	while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&
 760	       (rc == 0) && !cfile->srch_inf.endOfSearch) {
 761		cifs_dbg(FYI, "calling findnext2\n");
 762		rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,
 763						 search_flags,
 764						 &cfile->srch_inf);
 765		/* FindFirst/Next set last_entry to NULL on malformed reply */
 766		if (cfile->srch_inf.last_entry)
 767			cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
 768		if (rc)
 769			return -ENOENT;
 770	}
 771	if (index_to_find < cfile->srch_inf.index_of_last_entry) {
 772		/* we found the buffer that contains the entry */
 773		/* scan and find it */
 774		int i;
 775		char *cur_ent;
 776		char *end_of_smb;
 777
 778		if (cfile->srch_inf.ntwrk_buf_start == NULL) {
 779			cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n");
 780			return -EIO;
 781		}
 782
 783		end_of_smb = cfile->srch_inf.ntwrk_buf_start +
 784			server->ops->calc_smb_size(
 785					cfile->srch_inf.ntwrk_buf_start,
 786					server);
 787
 788		cur_ent = cfile->srch_inf.srch_entries_start;
 789		first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
 790					- cfile->srch_inf.entries_in_buffer;
 791		pos_in_buf = index_to_find - first_entry_in_buffer;
 792		cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);
 793
 794		for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
 795			/* go entry by entry figuring out which is first */
 796			cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
 797						cfile->srch_inf.info_level);
 798		}
 799		if ((cur_ent == NULL) && (i < pos_in_buf)) {
 800			/* BB fixme - check if we should flag this error */
 801			cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",
 802				 pos_in_buf, index_to_find, rc);
 803		}
 804		rc = 0;
 805		*current_entry = cur_ent;
 806	} else {
 807		cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");
 808		return 0;
 809	}
 810
 811	if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {
 812		cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");
 813		*num_to_ret = 0;
 814	} else
 815		*num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;
 816
 817	return rc;
 818}
 819
 820static int cifs_filldir(char *find_entry, struct file *file,
 821		struct dir_context *ctx,
 822		char *scratch_buf, unsigned int max_len)
 823{
 824	struct cifsFileInfo *file_info = file->private_data;
 825	struct super_block *sb = file_inode(file)->i_sb;
 826	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
 827	struct cifs_dirent de = { NULL, };
 828	struct cifs_fattr fattr;
 829	struct qstr name;
 830	int rc = 0;
 831	ino_t ino;
 832
 833	rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
 834			      file_info->srch_inf.unicode);
 835	if (rc)
 836		return rc;
 837
 838	if (de.namelen > max_len) {
 839		cifs_dbg(VFS, "bad search response length %zd past smb end\n",
 840			 de.namelen);
 841		return -EINVAL;
 842	}
 843
 844	/* skip . and .. since we added them first */
 845	if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
 846		return 0;
 847
 848	if (file_info->srch_inf.unicode) {
 849		struct nls_table *nlt = cifs_sb->local_nls;
 850		int map_type;
 851
 852		map_type = cifs_remap(cifs_sb);
 853		name.name = scratch_buf;
 854		name.len =
 855			cifs_from_utf16((char *)name.name, (__le16 *)de.name,
 856					UNICODE_NAME_MAX,
 857					min_t(size_t, de.namelen,
 858					      (size_t)max_len), nlt, map_type);
 859		name.len -= nls_nullsize(nlt);
 860	} else {
 861		name.name = de.name;
 862		name.len = de.namelen;
 863	}
 864
 865	switch (file_info->srch_inf.info_level) {
 866	case SMB_FIND_FILE_POSIX_INFO:
 867		cifs_posix_to_fattr(&fattr,
 868				    (struct smb2_posix_info *)find_entry,
 869				    cifs_sb);
 870		break;
 871	case SMB_FIND_FILE_UNIX:
 872		cifs_unix_basic_to_fattr(&fattr,
 873					 &((FILE_UNIX_INFO *)find_entry)->basic,
 874					 cifs_sb);
 875		break;
 876	case SMB_FIND_FILE_INFO_STANDARD:
 877		cifs_std_info_to_fattr(&fattr,
 878				       (FIND_FILE_STANDARD_INFO *)find_entry,
 879				       cifs_sb);
 880		break;
 881	case SMB_FIND_FILE_ID_FULL_DIR_INFO:
 882		cifs_fulldir_info_to_fattr(&fattr,
 883					   (SEARCH_ID_FULL_DIR_INFO *)find_entry,
 884					   cifs_sb);
 885		break;
 886	default:
 887		cifs_dir_info_to_fattr(&fattr,
 888				       (FILE_DIRECTORY_INFO *)find_entry,
 889				       cifs_sb);
 890		break;
 891	}
 892
 893	if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 894		fattr.cf_uniqueid = de.ino;
 895	} else {
 896		fattr.cf_uniqueid = iunique(sb, ROOT_I);
 897		cifs_autodisable_serverino(cifs_sb);
 898	}
 899
 900	if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
 901	    couldbe_mf_symlink(&fattr))
 902		/*
 903		 * trying to get the type and mode can be slow,
 904		 * so just call those regular files for now, and mark
 905		 * for reval
 906		 */
 907		fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
 908
 909	cifs_prime_dcache(file_dentry(file), &name, &fattr);
 910
 911	ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
 912	return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);
 913}
 914
 915
 916int cifs_readdir(struct file *file, struct dir_context *ctx)
 917{
 918	int rc = 0;
 919	unsigned int xid;
 920	int i;
 921	struct cifs_tcon *tcon;
 922	struct cifsFileInfo *cifsFile = NULL;
 923	char *current_entry;
 924	int num_to_fill = 0;
 925	char *tmp_buf = NULL;
 926	char *end_of_smb;
 927	unsigned int max_len;
 928
 929	xid = get_xid();
 930
 931	/*
 932	 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
 933	 * '..'. Otherwise we won't be able to notify VFS in case of failure.
 934	 */
 935	if (file->private_data == NULL) {
 936		rc = initiate_cifs_search(xid, file);
 937		cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
 938		if (rc)
 939			goto rddir2_exit;
 940	}
 941
 942	if (!dir_emit_dots(file, ctx))
 943		goto rddir2_exit;
 944
 945	/* 1) If search is active,
 946		is in current search buffer?
 947		if it before then restart search
 948		if after then keep searching till find it */
 949
 950	cifsFile = file->private_data;
 951	if (cifsFile->srch_inf.endOfSearch) {
 952		if (cifsFile->srch_inf.emptyDir) {
 953			cifs_dbg(FYI, "End of search, empty dir\n");
 954			rc = 0;
 955			goto rddir2_exit;
 956		}
 957	} /* else {
 958		cifsFile->invalidHandle = true;
 959		tcon->ses->server->close(xid, tcon, &cifsFile->fid);
 960	} */
 961
 962	tcon = tlink_tcon(cifsFile->tlink);
 963	rc = find_cifs_entry(xid, tcon, ctx->pos, file, &current_entry,
 964			     &num_to_fill);
 965	if (rc) {
 966		cifs_dbg(FYI, "fce error %d\n", rc);
 967		goto rddir2_exit;
 968	} else if (current_entry != NULL) {
 969		cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
 970	} else {
 971		cifs_dbg(FYI, "Could not find entry\n");
 972		goto rddir2_exit;
 973	}
 974	cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
 975		 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
 976	max_len = tcon->ses->server->ops->calc_smb_size(
 977			cifsFile->srch_inf.ntwrk_buf_start,
 978			tcon->ses->server);
 979	end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
 980
 981	tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
 982	if (tmp_buf == NULL) {
 983		rc = -ENOMEM;
 984		goto rddir2_exit;
 985	}
 986
 987	for (i = 0; i < num_to_fill; i++) {
 988		if (current_entry == NULL) {
 989			/* evaluate whether this case is an error */
 990			cifs_dbg(VFS, "past SMB end,  num to fill %d i %d\n",
 991				 num_to_fill, i);
 992			break;
 993		}
 994		/*
 995		 * if buggy server returns . and .. late do we want to
 996		 * check for that here?
 997		 */
 998		*tmp_buf = 0;
 999		rc = cifs_filldir(current_entry, file, ctx,
1000				  tmp_buf, max_len);
1001		if (rc) {
1002			if (rc > 0)
1003				rc = 0;
1004			break;
1005		}
1006
1007		ctx->pos++;
1008		if (ctx->pos ==
1009			cifsFile->srch_inf.index_of_last_entry) {
1010			cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
1011				 ctx->pos, tmp_buf);
1012			cifs_save_resume_key(current_entry, cifsFile);
1013			break;
1014		} else
1015			current_entry =
1016				nxt_dir_entry(current_entry, end_of_smb,
1017					cifsFile->srch_inf.info_level);
1018	}
1019	kfree(tmp_buf);
1020
1021rddir2_exit:
1022	free_xid(xid);
1023	return rc;
1024}