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/slab.h>
  26 #include <linux/stat.h>
  27 #include "cifspdu.h"
  28 #include "cifsglob.h"
  29 #include "cifsproto.h"
  30 #include "cifs_unicode.h"
  31 #include "cifs_debug.h"
  32 #include "cifs_fs_sb.h"
  33 #include "cifsfs.h"
  34
  35 /*
  36  * To be safe - for UCS to UTF-8 with strings loaded with the rare long
  37  * characters alloc more to account for such multibyte target UTF-8
  38  * characters.
  39  */
  40 #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
  41
  42 #ifdef CONFIG_CIFS_DEBUG2
  43 static void dump_cifs_file_struct(struct file *file, char *label)
  44 {
  45         struct cifsFileInfo *cf;
  46
  47         if (file) {
  48                 cf = file->private_data;
  49                 if (cf == NULL) {
  50                         cFYI(1, "empty cifs private file data");
  51                         return;
  52                 }
  53                 if (cf->invalidHandle)
  54                         cFYI(1, "invalid handle");
  55                 if (cf->srch_inf.endOfSearch)
  56                         cFYI(1, "end of search");
  57                 if (cf->srch_inf.emptyDir)
  58                         cFYI(1, "empty dir");
  59         }
  60 }
  61 #else
  62 static inline void dump_cifs_file_struct(struct file *file, char *label)
  63 {
  64 }
  65 #endif /* DEBUG2 */
  66
  67 /*
  68  * Find the dentry that matches "name". If there isn't one, create one. If it's
  69  * a negative dentry or the uniqueid changed, then drop it and recreate it.
  70  */
  71 static struct dentry *
  72 cifs_readdir_lookup(struct dentry *parent, struct qstr *name,
  73                     struct cifs_fattr *fattr)
  74 {
  75         struct dentry *dentry, *alias;
  76         struct inode *inode;
  77         struct super_block *sb = parent->d_inode->i_sb;
  78
  79         cFYI(1, "For %s", name->name);
  80
  81         if (parent->d_op && parent->d_op->d_hash)
  82                 parent->d_op->d_hash(parent, parent->d_inode, name);
  83         else
  84                 name->hash = full_name_hash(name->name, name->len);
  85
  86         dentry = d_lookup(parent, name);
  87         if (dentry) {
  88                 /* FIXME: check for inode number changes? */
  89                 if (dentry->d_inode != NULL)
  90                         return dentry;
  91                 d_drop(dentry);
  92                 dput(dentry);
  93         }
  94
  95         dentry = d_alloc(parent, name);
  96         if (dentry == NULL)
  97                 return NULL;
  98
  99         inode = cifs_iget(sb, fattr);
 100         if (!inode) {
 101                 dput(dentry);
 102                 return NULL;
 103         }
 104
 105         if (cifs_sb_master_tcon(CIFS_SB(sb))->nocase)
 106                 d_set_d_op(dentry, &cifs_ci_dentry_ops);
 107         else
 108                 d_set_d_op(dentry, &cifs_dentry_ops);
 109
 110         alias = d_materialise_unique(dentry, inode);
 111         if (alias != NULL) {
 112                 dput(dentry);
 113                 if (IS_ERR(alias))
 114                         return NULL;
 115                 dentry = alias;
 116         }
 117
 118         return dentry;
 119 }
 120
 121 static void
 122 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
 123 {
 124         fattr->cf_uid = cifs_sb->mnt_uid;
 125         fattr->cf_gid = cifs_sb->mnt_gid;
 126
 127         if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
 128                 fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
 129                 fattr->cf_dtype = DT_DIR;
 130         } else {
 131                 fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
 132                 fattr->cf_dtype = DT_REG;
 133         }
 134
 135         if (fattr->cf_cifsattrs & ATTR_READONLY)
 136                 fattr->cf_mode &= ~S_IWUGO;
 137
 138         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
 139             fattr->cf_cifsattrs & ATTR_SYSTEM) {
 140                 if (fattr->cf_eof == 0)  {
 141                         fattr->cf_mode &= ~S_IFMT;
 142                         fattr->cf_mode |= S_IFIFO;
 143                         fattr->cf_dtype = DT_FIFO;
 144                 } else {
 145                         /*
 146                          * trying to get the type and mode via SFU can be slow,
 147                          * so just call those regular files for now, and mark
 148                          * for reval
 149                          */
 150                         fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
 151                 }
 152         }
 153 }
 154
 155 static void
 156 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
 157                        struct cifs_sb_info *cifs_sb)
 158 {
 159         memset(fattr, 0, sizeof(*fattr));
 160         fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
 161         fattr->cf_eof = le64_to_cpu(info->EndOfFile);
 162         fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
 163         fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
 164         fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
 165         fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
 166
 167         cifs_fill_common_info(fattr, cifs_sb);
 168 }
 169
 170 static void
 171 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
 172                        struct cifs_sb_info *cifs_sb)
 173 {
 174         int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
 175
 176         memset(fattr, 0, sizeof(*fattr));
 177         fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
 178                                             info->LastAccessTime, offset);
 179         fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
 180                                             info->LastWriteTime, offset);
 181         fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
 182                                             info->LastWriteTime, offset);
 183
 184         fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
 185         fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
 186         fattr->cf_eof = le32_to_cpu(info->DataSize);
 187
 188         cifs_fill_common_info(fattr, cifs_sb);
 189 }
 190
 191 /* BB eventually need to add the following helper function to
 192       resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
 193       we try to do FindFirst on (NTFS) directory symlinks */
 194 /*
 195 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
 196                              int xid)
 197 {
 198         __u16 fid;
 199         int len;
 200         int oplock = 0;
 201         int rc;
 202         struct cifsTconInfo *ptcon = cifs_sb_tcon(cifs_sb);
 203         char *tmpbuffer;
 204
 205         rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
 206                         OPEN_REPARSE_POINT, &fid, &oplock, NULL,
 207                         cifs_sb->local_nls,
 208                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 209         if (!rc) {
 210                 tmpbuffer = kmalloc(maxpath);
 211                 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
 212                                 tmpbuffer,
 213                                 maxpath -1,
 214                                 fid,
 215                                 cifs_sb->local_nls);
 216                 if (CIFSSMBClose(xid, ptcon, fid)) {
 217                         cFYI(1, "Error closing temporary reparsepoint open");
 218                 }
 219         }
 220 }
 221  */
 222
 223 static int initiate_cifs_search(const int xid, struct file *file)
 224 {
 225         int rc = 0;
 226         char *full_path = NULL;
 227         struct cifsFileInfo *cifsFile;
 228         struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 229         struct tcon_link *tlink = NULL;
 230         struct cifsTconInfo *pTcon;
 231
 232         if (file->private_data == NULL) {
 233                 tlink = cifs_sb_tlink(cifs_sb);
 234                 if (IS_ERR(tlink))
 235                         return PTR_ERR(tlink);
 236
 237                 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
 238                 if (cifsFile == NULL) {
 239                         rc = -ENOMEM;
 240                         goto error_exit;
 241                 }
 242                 file->private_data = cifsFile;
 243                 cifsFile->tlink = cifs_get_tlink(tlink);
 244                 pTcon = tlink_tcon(tlink);
 245         } else {
 246                 cifsFile = file->private_data;
 247                 pTcon = tlink_tcon(cifsFile->tlink);
 248         }
 249
 250         cifsFile->invalidHandle = true;
 251         cifsFile->srch_inf.endOfSearch = false;
 252
 253         full_path = build_path_from_dentry(file->f_path.dentry);
 254         if (full_path == NULL) {
 255                 rc = -ENOMEM;
 256                 goto error_exit;
 257         }
 258
 259         cFYI(1, "Full path: %s start at: %lld", full_path, file->f_pos);
 260
 261 ffirst_retry:
 262         /* test for Unix extensions */
 263         /* but now check for them on the share/mount not on the SMB session */
 264 /*      if (pTcon->ses->capabilities & CAP_UNIX) { */
 265         if (pTcon->unix_ext)
 266                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
 267         else if ((pTcon->ses->capabilities &
 268                         (CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
 269                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
 270         } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
 271                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
 272         } else /* not srvinos - BB fixme add check for backlevel? */ {
 273                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
 274         }
 275
 276         rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
 277                 &cifsFile->netfid, &cifsFile->srch_inf,
 278                 cifs_sb->mnt_cifs_flags &
 279                         CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
 280         if (rc == 0)
 281                 cifsFile->invalidHandle = false;
 282         /* BB add following call to handle readdir on new NTFS symlink errors
 283         else if STATUS_STOPPED_ON_SYMLINK
 284                 call get_symlink_reparse_path and retry with new path */
 285         else if ((rc == -EOPNOTSUPP) &&
 286                 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 287                 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
 288                 goto ffirst_retry;
 289         }
 290 error_exit:
 291         kfree(full_path);
 292         cifs_put_tlink(tlink);
 293         return rc;
 294 }
 295
 296 /* return length of unicode string in bytes */
 297 static int cifs_unicode_bytelen(char *str)
 298 {
 299         int len;
 300         __le16 *ustr = (__le16 *)str;
 301
 302         for (len = 0; len <= PATH_MAX; len++) {
 303                 if (ustr[len] == 0)
 304                         return len << 1;
 305         }
 306         cFYI(1, "Unicode string longer than PATH_MAX found");
 307         return len << 1;
 308 }
 309
 310 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
 311 {
 312         char *new_entry;
 313         FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
 314
 315         if (level == SMB_FIND_FILE_INFO_STANDARD) {
 316                 FIND_FILE_STANDARD_INFO *pfData;
 317                 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
 318
 319                 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
 320                                 pfData->FileNameLength;
 321         } else
 322                 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
 323         cFYI(1, "new entry %p old entry %p", new_entry, old_entry);
 324         /* validate that new_entry is not past end of SMB */
 325         if (new_entry >= end_of_smb) {
 326                 cERROR(1, "search entry %p began after end of SMB %p old entry %p",
 327                         new_entry, end_of_smb, old_entry);
 328                 return NULL;
 329         } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
 330                     (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
 331                   || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
 332                    (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
 333                 cERROR(1, "search entry %p extends after end of SMB %p",
 334                         new_entry, end_of_smb);
 335                 return NULL;
 336         } else
 337                 return new_entry;
 338
 339 }
 340
 341 #define UNICODE_DOT cpu_to_le16(0x2e)
 342
 343 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
 344 static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
 345 {
 346         int rc = 0;
 347         char *filename = NULL;
 348         int len = 0;
 349
 350         if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
 351                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 352                 filename = &pFindData->FileName[0];
 353                 if (cfile->srch_inf.unicode) {
 354                         len = cifs_unicode_bytelen(filename);
 355                 } else {
 356                         /* BB should we make this strnlen of PATH_MAX? */
 357                         len = strnlen(filename, 5);
 358                 }
 359         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
 360                 FILE_DIRECTORY_INFO *pFindData =
 361                         (FILE_DIRECTORY_INFO *)current_entry;
 362                 filename = &pFindData->FileName[0];
 363                 len = le32_to_cpu(pFindData->FileNameLength);
 364         } else if (cfile->srch_inf.info_level ==
 365                         SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 366                 FILE_FULL_DIRECTORY_INFO *pFindData =
 367                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 368                 filename = &pFindData->FileName[0];
 369                 len = le32_to_cpu(pFindData->FileNameLength);
 370         } else if (cfile->srch_inf.info_level ==
 371                         SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 372                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 373                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 374                 filename = &pFindData->FileName[0];
 375                 len = le32_to_cpu(pFindData->FileNameLength);
 376         } else if (cfile->srch_inf.info_level ==
 377                         SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 378                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 379                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 380                 filename = &pFindData->FileName[0];
 381                 len = le32_to_cpu(pFindData->FileNameLength);
 382         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
 383                 FIND_FILE_STANDARD_INFO *pFindData =
 384                         (FIND_FILE_STANDARD_INFO *)current_entry;
 385                 filename = &pFindData->FileName[0];
 386                 len = pFindData->FileNameLength;
 387         } else {
 388                 cFYI(1, "Unknown findfirst level %d",
 389                          cfile->srch_inf.info_level);
 390         }
 391
 392         if (filename) {
 393                 if (cfile->srch_inf.unicode) {
 394                         __le16 *ufilename = (__le16 *)filename;
 395                         if (len == 2) {
 396                                 /* check for . */
 397                                 if (ufilename[0] == UNICODE_DOT)
 398                                         rc = 1;
 399                         } else if (len == 4) {
 400                                 /* check for .. */
 401                                 if ((ufilename[0] == UNICODE_DOT)
 402                                    && (ufilename[1] == UNICODE_DOT))
 403                                         rc = 2;
 404                         }
 405                 } else /* ASCII */ {
 406                         if (len == 1) {
 407                                 if (filename[0] == '.')
 408                                         rc = 1;
 409                         } else if (len == 2) {
 410                                 if ((filename[0] == '.') && (filename[1] == '.'))
 411                                         rc = 2;
 412                         }
 413                 }
 414         }
 415
 416         return rc;
 417 }
 418
 419 /* Check if directory that we are searching has changed so we can decide
 420    whether we can use the cached search results from the previous search */
 421 static int is_dir_changed(struct file *file)
 422 {
 423         struct inode *inode = file->f_path.dentry->d_inode;
 424         struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
 425
 426         if (cifsInfo->time == 0)
 427                 return 1; /* directory was changed, perhaps due to unlink */
 428         else
 429                 return 0;
 430
 431 }
 432
 433 static int cifs_save_resume_key(const char *current_entry,
 434         struct cifsFileInfo *cifsFile)
 435 {
 436         int rc = 0;
 437         unsigned int len = 0;
 438         __u16 level;
 439         char *filename;
 440
 441         if ((cifsFile == NULL) || (current_entry == NULL))
 442                 return -EINVAL;
 443
 444         level = cifsFile->srch_inf.info_level;
 445
 446         if (level == SMB_FIND_FILE_UNIX) {
 447                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 448
 449                 filename = &pFindData->FileName[0];
 450                 if (cifsFile->srch_inf.unicode) {
 451                         len = cifs_unicode_bytelen(filename);
 452                 } else {
 453                         /* BB should we make this strnlen of PATH_MAX? */
 454                         len = strnlen(filename, PATH_MAX);
 455                 }
 456                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 457         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 458                 FILE_DIRECTORY_INFO *pFindData =
 459                         (FILE_DIRECTORY_INFO *)current_entry;
 460                 filename = &pFindData->FileName[0];
 461                 len = le32_to_cpu(pFindData->FileNameLength);
 462                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 463         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 464                 FILE_FULL_DIRECTORY_INFO *pFindData =
 465                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 466                 filename = &pFindData->FileName[0];
 467                 len = le32_to_cpu(pFindData->FileNameLength);
 468                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 469         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 470                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 471                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 472                 filename = &pFindData->FileName[0];
 473                 len = le32_to_cpu(pFindData->FileNameLength);
 474                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 475         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 476                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 477                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 478                 filename = &pFindData->FileName[0];
 479                 len = le32_to_cpu(pFindData->FileNameLength);
 480                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 481         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 482                 FIND_FILE_STANDARD_INFO *pFindData =
 483                         (FIND_FILE_STANDARD_INFO *)current_entry;
 484                 filename = &pFindData->FileName[0];
 485                 /* one byte length, no name conversion */
 486                 len = (unsigned int)pFindData->FileNameLength;
 487                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 488         } else {
 489                 cFYI(1, "Unknown findfirst level %d", level);
 490                 return -EINVAL;
 491         }
 492         cifsFile->srch_inf.resume_name_len = len;
 493         cifsFile->srch_inf.presume_name = filename;
 494         return rc;
 495 }
 496
 497 /* find the corresponding entry in the search */
 498 /* Note that the SMB server returns search entries for . and .. which
 499    complicates logic here if we choose to parse for them and we do not
 500    assume that they are located in the findfirst return buffer.*/
 501 /* We start counting in the buffer with entry 2 and increment for every
 502    entry (do not increment for . or .. entry) */
 503 static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
 504         struct file *file, char **ppCurrentEntry, int *num_to_ret)
 505 {
 506         int rc = 0;
 507         int pos_in_buf = 0;
 508         loff_t first_entry_in_buffer;
 509         loff_t index_to_find = file->f_pos;
 510         struct cifsFileInfo *cifsFile = file->private_data;
 511         /* check if index in the buffer */
 512
 513         if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
 514            (num_to_ret == NULL))
 515                 return -ENOENT;
 516
 517         *ppCurrentEntry = NULL;
 518         first_entry_in_buffer =
 519                 cifsFile->srch_inf.index_of_last_entry -
 520                         cifsFile->srch_inf.entries_in_buffer;
 521
 522         /* if first entry in buf is zero then is first buffer
 523         in search response data which means it is likely . and ..
 524         will be in this buffer, although some servers do not return
 525         . and .. for the root of a drive and for those we need
 526         to start two entries earlier */
 527
 528         dump_cifs_file_struct(file, "In fce ");
 529         if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
 530              is_dir_changed(file)) ||
 531            (index_to_find < first_entry_in_buffer)) {
 532                 /* close and restart search */
 533                 cFYI(1, "search backing up - close and restart search");
 534                 spin_lock(&cifs_file_list_lock);
 535                 if (!cifsFile->srch_inf.endOfSearch &&
 536                     !cifsFile->invalidHandle) {
 537                         cifsFile->invalidHandle = true;
 538                         spin_unlock(&cifs_file_list_lock);
 539                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 540                 } else
 541                         spin_unlock(&cifs_file_list_lock);
 542                 if (cifsFile->srch_inf.ntwrk_buf_start) {
 543                         cFYI(1, "freeing SMB ff cache buf on search rewind");
 544                         if (cifsFile->srch_inf.smallBuf)
 545                                 cifs_small_buf_release(cifsFile->srch_inf.
 546                                                 ntwrk_buf_start);
 547                         else
 548                                 cifs_buf_release(cifsFile->srch_inf.
 549                                                 ntwrk_buf_start);
 550                         cifsFile->srch_inf.ntwrk_buf_start = NULL;
 551                 }
 552                 rc = initiate_cifs_search(xid, file);
 553                 if (rc) {
 554                         cFYI(1, "error %d reinitiating a search on rewind",
 555                                  rc);
 556                         return rc;
 557                 }
 558                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 559         }
 560
 561         while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
 562               (rc == 0) && !cifsFile->srch_inf.endOfSearch) {
 563                 cFYI(1, "calling findnext2");
 564                 rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
 565                                   &cifsFile->srch_inf);
 566                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 567                 if (rc)
 568                         return -ENOENT;
 569         }
 570         if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
 571                 /* we found the buffer that contains the entry */
 572                 /* scan and find it */
 573                 int i;
 574                 char *current_entry;
 575                 char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
 576                         smbCalcSize((struct smb_hdr *)
 577                                 cifsFile->srch_inf.ntwrk_buf_start);
 578
 579                 current_entry = cifsFile->srch_inf.srch_entries_start;
 580                 first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
 581                                         - cifsFile->srch_inf.entries_in_buffer;
 582                 pos_in_buf = index_to_find - first_entry_in_buffer;
 583                 cFYI(1, "found entry - pos_in_buf %d", pos_in_buf);
 584
 585                 for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
 586                         /* go entry by entry figuring out which is first */
 587                         current_entry = nxt_dir_entry(current_entry, end_of_smb,
 588                                                 cifsFile->srch_inf.info_level);
 589                 }
 590                 if ((current_entry == NULL) && (i < pos_in_buf)) {
 591                         /* BB fixme - check if we should flag this error */
 592                         cERROR(1, "reached end of buf searching for pos in buf"
 593                           " %d index to find %lld rc %d",
 594                           pos_in_buf, index_to_find, rc);
 595                 }
 596                 rc = 0;
 597                 *ppCurrentEntry = current_entry;
 598         } else {
 599                 cFYI(1, "index not in buffer - could not findnext into it");
 600                 return 0;
 601         }
 602
 603         if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
 604                 cFYI(1, "can not return entries pos_in_buf beyond last");
 605                 *num_to_ret = 0;
 606         } else
 607                 *num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
 608
 609         return rc;
 610 }
 611
 612 /* inode num, inode type and filename returned */
 613 static int cifs_get_name_from_search_buf(struct qstr *pqst,
 614         char *current_entry, __u16 level, unsigned int unicode,
 615         struct cifs_sb_info *cifs_sb, unsigned int max_len, __u64 *pinum)
 616 {
 617         int rc = 0;
 618         unsigned int len = 0;
 619         char *filename;
 620         struct nls_table *nlt = cifs_sb->local_nls;
 621
 622         *pinum = 0;
 623
 624         if (level == SMB_FIND_FILE_UNIX) {
 625                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 626
 627                 filename = &pFindData->FileName[0];
 628                 if (unicode) {
 629                         len = cifs_unicode_bytelen(filename);
 630                 } else {
 631                         /* BB should we make this strnlen of PATH_MAX? */
 632                         len = strnlen(filename, PATH_MAX);
 633                 }
 634
 635                 *pinum = le64_to_cpu(pFindData->basic.UniqueId);
 636         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 637                 FILE_DIRECTORY_INFO *pFindData =
 638                         (FILE_DIRECTORY_INFO *)current_entry;
 639                 filename = &pFindData->FileName[0];
 640                 len = le32_to_cpu(pFindData->FileNameLength);
 641         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 642                 FILE_FULL_DIRECTORY_INFO *pFindData =
 643                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 644                 filename = &pFindData->FileName[0];
 645                 len = le32_to_cpu(pFindData->FileNameLength);
 646         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 647                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 648                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 649                 filename = &pFindData->FileName[0];
 650                 len = le32_to_cpu(pFindData->FileNameLength);
 651                 *pinum = le64_to_cpu(pFindData->UniqueId);
 652         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 653                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 654                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 655                 filename = &pFindData->FileName[0];
 656                 len = le32_to_cpu(pFindData->FileNameLength);
 657         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 658                 FIND_FILE_STANDARD_INFO *pFindData =
 659                         (FIND_FILE_STANDARD_INFO *)current_entry;
 660                 filename = &pFindData->FileName[0];
 661                 /* one byte length, no name conversion */
 662                 len = (unsigned int)pFindData->FileNameLength;
 663         } else {
 664                 cFYI(1, "Unknown findfirst level %d", level);
 665                 return -EINVAL;
 666         }
 667
 668         if (len > max_len) {
 669                 cERROR(1, "bad search response length %d past smb end", len);
 670                 return -EINVAL;
 671         }
 672
 673         if (unicode) {
 674                 pqst->len = cifs_from_ucs2((char *) pqst->name,
 675                                            (__le16 *) filename,
 676                                            UNICODE_NAME_MAX,
 677                                            min(len, max_len), nlt,
 678                                            cifs_sb->mnt_cifs_flags &
 679                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 680                 pqst->len -= nls_nullsize(nlt);
 681         } else {
 682                 pqst->name = filename;
 683                 pqst->len = len;
 684         }
 685         return rc;
 686 }
 687
 688 static int cifs_filldir(char *pfindEntry, struct file *file, filldir_t filldir,
 689                         void *direntry, char *scratch_buf, unsigned int max_len)
 690 {
 691         int rc = 0;
 692         struct qstr qstring;
 693         struct cifsFileInfo *pCifsF;
 694         u64    inum;
 695         ino_t  ino;
 696         struct super_block *sb;
 697         struct cifs_sb_info *cifs_sb;
 698         struct dentry *tmp_dentry;
 699         struct cifs_fattr fattr;
 700
 701         /* get filename and len into qstring */
 702         /* get dentry */
 703         /* decide whether to create and populate ionde */
 704         if ((direntry == NULL) || (file == NULL))
 705                 return -EINVAL;
 706
 707         pCifsF = file->private_data;
 708
 709         if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
 710                 return -ENOENT;
 711
 712         rc = cifs_entry_is_dot(pfindEntry, pCifsF);
 713         /* skip . and .. since we added them first */
 714         if (rc != 0)
 715                 return 0;
 716
 717         sb = file->f_path.dentry->d_sb;
 718         cifs_sb = CIFS_SB(sb);
 719
 720         qstring.name = scratch_buf;
 721         rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
 722                         pCifsF->srch_inf.info_level,
 723                         pCifsF->srch_inf.unicode, cifs_sb,
 724                         max_len, &inum /* returned */);
 725
 726         if (rc)
 727                 return rc;
 728
 729         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
 730                 cifs_unix_basic_to_fattr(&fattr,
 731                                  &((FILE_UNIX_INFO *) pfindEntry)->basic,
 732                                  cifs_sb);
 733         else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
 734                 cifs_std_info_to_fattr(&fattr, (FIND_FILE_STANDARD_INFO *)
 735                                         pfindEntry, cifs_sb);
 736         else
 737                 cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)
 738                                         pfindEntry, cifs_sb);
 739
 740         if (inum && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 741                 fattr.cf_uniqueid = inum;
 742         } else {
 743                 fattr.cf_uniqueid = iunique(sb, ROOT_I);
 744                 cifs_autodisable_serverino(cifs_sb);
 745         }
 746
 747         if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
 748             CIFSCouldBeMFSymlink(&fattr))
 749                 /*
 750                  * trying to get the type and mode can be slow,
 751                  * so just call those regular files for now, and mark
 752                  * for reval
 753                  */
 754                 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
 755
 756         ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
 757         tmp_dentry = cifs_readdir_lookup(file->f_dentry, &qstring, &fattr);
 758
 759         rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
 760                      ino, fattr.cf_dtype);
 761
 762         dput(tmp_dentry);
 763         return rc;
 764 }
 765
 766
 767 int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
 768 {
 769         int rc = 0;
 770         int xid, i;
 771         struct cifs_sb_info *cifs_sb;
 772         struct cifsTconInfo *pTcon;
 773         struct cifsFileInfo *cifsFile = NULL;
 774         char *current_entry;
 775         int num_to_fill = 0;
 776         char *tmp_buf = NULL;
 777         char *end_of_smb;
 778         unsigned int max_len;
 779
 780         xid = GetXid();
 781
 782         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 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                 cFYI(1, "initiate cifs search rc %d", rc);
 791                 if (rc)
 792                         goto rddir2_exit;
 793         }
 794
 795         switch ((int) file->f_pos) {
 796         case 0:
 797                 if (filldir(direntry, ".", 1, file->f_pos,
 798                      file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
 799                         cERROR(1, "Filldir for current dir failed");
 800                         rc = -ENOMEM;
 801                         break;
 802                 }
 803                 file->f_pos++;
 804         case 1:
 805                 if (filldir(direntry, "..", 2, file->f_pos,
 806                      file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
 807                         cERROR(1, "Filldir for parent dir failed");
 808                         rc = -ENOMEM;
 809                         break;
 810                 }
 811                 file->f_pos++;
 812         default:
 813                 /* 1) If search is active,
 814                         is in current search buffer?
 815                         if it before then restart search
 816                         if after then keep searching till find it */
 817
 818                 if (file->private_data == NULL) {
 819                         rc = -EINVAL;
 820                         FreeXid(xid);
 821                         return rc;
 822                 }
 823                 cifsFile = file->private_data;
 824                 if (cifsFile->srch_inf.endOfSearch) {
 825                         if (cifsFile->srch_inf.emptyDir) {
 826                                 cFYI(1, "End of search, empty dir");
 827                                 rc = 0;
 828                                 break;
 829                         }
 830                 } /* else {
 831                         cifsFile->invalidHandle = true;
 832                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 833                 } */
 834
 835                 pTcon = tlink_tcon(cifsFile->tlink);
 836                 rc = find_cifs_entry(xid, pTcon, file,
 837                                 &current_entry, &num_to_fill);
 838                 if (rc) {
 839                         cFYI(1, "fce error %d", rc);
 840                         goto rddir2_exit;
 841                 } else if (current_entry != NULL) {
 842                         cFYI(1, "entry %lld found", file->f_pos);
 843                 } else {
 844                         cFYI(1, "could not find entry");
 845                         goto rddir2_exit;
 846                 }
 847                 cFYI(1, "loop through %d times filling dir for net buf %p",
 848                         num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
 849                 max_len = smbCalcSize((struct smb_hdr *)
 850                                 cifsFile->srch_inf.ntwrk_buf_start);
 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                         break;
 857                 }
 858
 859                 for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
 860                         if (current_entry == NULL) {
 861                                 /* evaluate whether this case is an error */
 862                                 cERROR(1, "past SMB end,  num to fill %d i %d",
 863                                           num_to_fill, i);
 864                                 break;
 865                         }
 866                         /* if buggy server returns . and .. late do
 867                         we want to check for that here? */
 868                         rc = cifs_filldir(current_entry, file,
 869                                         filldir, direntry, tmp_buf, max_len);
 870                         if (rc == -EOVERFLOW) {
 871                                 rc = 0;
 872                                 break;
 873                         }
 874
 875                         file->f_pos++;
 876                         if (file->f_pos ==
 877                                 cifsFile->srch_inf.index_of_last_entry) {
 878                                 cFYI(1, "last entry in buf at pos %lld %s",
 879                                         file->f_pos, tmp_buf);
 880                                 cifs_save_resume_key(current_entry, cifsFile);
 881                                 break;
 882                         } else
 883                                 current_entry =
 884                                         nxt_dir_entry(current_entry, end_of_smb,
 885                                                 cifsFile->srch_inf.info_level);
 886                 }
 887                 kfree(tmp_buf);
 888                 break;
 889         } /* end switch */
 890
 891 rddir2_exit:
 892         FreeXid(xid);
 893         return rc;
 894 }