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_createtime = le64_to_cpu(info->CreationTime);
 164         fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
 165         fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
 166         fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
 167
 168         cifs_fill_common_info(fattr, cifs_sb);
 169 }
 170
 171 static void
 172 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
 173                        struct cifs_sb_info *cifs_sb)
 174 {
 175         int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
 176
 177         memset(fattr, 0, sizeof(*fattr));
 178         fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
 179                                             info->LastAccessTime, offset);
 180         fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
 181                                             info->LastWriteTime, offset);
 182         fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
 183                                             info->LastWriteTime, offset);
 184
 185         fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
 186         fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
 187         fattr->cf_eof = le32_to_cpu(info->DataSize);
 188
 189         cifs_fill_common_info(fattr, cifs_sb);
 190 }
 191
 192 /* BB eventually need to add the following helper function to
 193       resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
 194       we try to do FindFirst on (NTFS) directory symlinks */
 195 /*
 196 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
 197                              int xid)
 198 {
 199         __u16 fid;
 200         int len;
 201         int oplock = 0;
 202         int rc;
 203         struct cifsTconInfo *ptcon = cifs_sb_tcon(cifs_sb);
 204         char *tmpbuffer;
 205
 206         rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
 207                         OPEN_REPARSE_POINT, &fid, &oplock, NULL,
 208                         cifs_sb->local_nls,
 209                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 210         if (!rc) {
 211                 tmpbuffer = kmalloc(maxpath);
 212                 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
 213                                 tmpbuffer,
 214                                 maxpath -1,
 215                                 fid,
 216                                 cifs_sb->local_nls);
 217                 if (CIFSSMBClose(xid, ptcon, fid)) {
 218                         cFYI(1, "Error closing temporary reparsepoint open");
 219                 }
 220         }
 221 }
 222  */
 223
 224 static int initiate_cifs_search(const int xid, struct file *file)
 225 {
 226         int rc = 0;
 227         char *full_path = NULL;
 228         struct cifsFileInfo *cifsFile;
 229         struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 230         struct tcon_link *tlink = NULL;
 231         struct cifsTconInfo *pTcon;
 232
 233         if (file->private_data == NULL) {
 234                 tlink = cifs_sb_tlink(cifs_sb);
 235                 if (IS_ERR(tlink))
 236                         return PTR_ERR(tlink);
 237
 238                 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
 239                 if (cifsFile == NULL) {
 240                         rc = -ENOMEM;
 241                         goto error_exit;
 242                 }
 243                 file->private_data = cifsFile;
 244                 cifsFile->tlink = cifs_get_tlink(tlink);
 245                 pTcon = tlink_tcon(tlink);
 246         } else {
 247                 cifsFile = file->private_data;
 248                 pTcon = tlink_tcon(cifsFile->tlink);
 249         }
 250
 251         cifsFile->invalidHandle = true;
 252         cifsFile->srch_inf.endOfSearch = false;
 253
 254         full_path = build_path_from_dentry(file->f_path.dentry);
 255         if (full_path == NULL) {
 256                 rc = -ENOMEM;
 257                 goto error_exit;
 258         }
 259
 260         cFYI(1, "Full path: %s start at: %lld", full_path, file->f_pos);
 261
 262 ffirst_retry:
 263         /* test for Unix extensions */
 264         /* but now check for them on the share/mount not on the SMB session */
 265 /*      if (pTcon->ses->capabilities & CAP_UNIX) { */
 266         if (pTcon->unix_ext)
 267                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
 268         else if ((pTcon->ses->capabilities &
 269                         (CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
 270                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
 271         } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
 272                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
 273         } else /* not srvinos - BB fixme add check for backlevel? */ {
 274                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
 275         }
 276
 277         rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
 278                 &cifsFile->netfid, &cifsFile->srch_inf,
 279                 cifs_sb->mnt_cifs_flags &
 280                         CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
 281         if (rc == 0)
 282                 cifsFile->invalidHandle = false;
 283         /* BB add following call to handle readdir on new NTFS symlink errors
 284         else if STATUS_STOPPED_ON_SYMLINK
 285                 call get_symlink_reparse_path and retry with new path */
 286         else if ((rc == -EOPNOTSUPP) &&
 287                 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 288                 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
 289                 goto ffirst_retry;
 290         }
 291 error_exit:
 292         kfree(full_path);
 293         cifs_put_tlink(tlink);
 294         return rc;
 295 }
 296
 297 /* return length of unicode string in bytes */
 298 static int cifs_unicode_bytelen(char *str)
 299 {
 300         int len;
 301         __le16 *ustr = (__le16 *)str;
 302
 303         for (len = 0; len <= PATH_MAX; len++) {
 304                 if (ustr[len] == 0)
 305                         return len << 1;
 306         }
 307         cFYI(1, "Unicode string longer than PATH_MAX found");
 308         return len << 1;
 309 }
 310
 311 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
 312 {
 313         char *new_entry;
 314         FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
 315
 316         if (level == SMB_FIND_FILE_INFO_STANDARD) {
 317                 FIND_FILE_STANDARD_INFO *pfData;
 318                 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
 319
 320                 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
 321                                 pfData->FileNameLength;
 322         } else
 323                 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
 324         cFYI(1, "new entry %p old entry %p", new_entry, old_entry);
 325         /* validate that new_entry is not past end of SMB */
 326         if (new_entry >= end_of_smb) {
 327                 cERROR(1, "search entry %p began after end of SMB %p old entry %p",
 328                         new_entry, end_of_smb, old_entry);
 329                 return NULL;
 330         } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
 331                     (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
 332                   || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
 333                    (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
 334                 cERROR(1, "search entry %p extends after end of SMB %p",
 335                         new_entry, end_of_smb);
 336                 return NULL;
 337         } else
 338                 return new_entry;
 339
 340 }
 341
 342 #define UNICODE_DOT cpu_to_le16(0x2e)
 343
 344 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
 345 static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
 346 {
 347         int rc = 0;
 348         char *filename = NULL;
 349         int len = 0;
 350
 351         if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
 352                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 353                 filename = &pFindData->FileName[0];
 354                 if (cfile->srch_inf.unicode) {
 355                         len = cifs_unicode_bytelen(filename);
 356                 } else {
 357                         /* BB should we make this strnlen of PATH_MAX? */
 358                         len = strnlen(filename, 5);
 359                 }
 360         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
 361                 FILE_DIRECTORY_INFO *pFindData =
 362                         (FILE_DIRECTORY_INFO *)current_entry;
 363                 filename = &pFindData->FileName[0];
 364                 len = le32_to_cpu(pFindData->FileNameLength);
 365         } else if (cfile->srch_inf.info_level ==
 366                         SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 367                 FILE_FULL_DIRECTORY_INFO *pFindData =
 368                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 369                 filename = &pFindData->FileName[0];
 370                 len = le32_to_cpu(pFindData->FileNameLength);
 371         } else if (cfile->srch_inf.info_level ==
 372                         SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 373                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 374                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 375                 filename = &pFindData->FileName[0];
 376                 len = le32_to_cpu(pFindData->FileNameLength);
 377         } else if (cfile->srch_inf.info_level ==
 378                         SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 379                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 380                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 381                 filename = &pFindData->FileName[0];
 382                 len = le32_to_cpu(pFindData->FileNameLength);
 383         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
 384                 FIND_FILE_STANDARD_INFO *pFindData =
 385                         (FIND_FILE_STANDARD_INFO *)current_entry;
 386                 filename = &pFindData->FileName[0];
 387                 len = pFindData->FileNameLength;
 388         } else {
 389                 cFYI(1, "Unknown findfirst level %d",
 390                          cfile->srch_inf.info_level);
 391         }
 392
 393         if (filename) {
 394                 if (cfile->srch_inf.unicode) {
 395                         __le16 *ufilename = (__le16 *)filename;
 396                         if (len == 2) {
 397                                 /* check for . */
 398                                 if (ufilename[0] == UNICODE_DOT)
 399                                         rc = 1;
 400                         } else if (len == 4) {
 401                                 /* check for .. */
 402                                 if ((ufilename[0] == UNICODE_DOT)
 403                                    && (ufilename[1] == UNICODE_DOT))
 404                                         rc = 2;
 405                         }
 406                 } else /* ASCII */ {
 407                         if (len == 1) {
 408                                 if (filename[0] == '.')
 409                                         rc = 1;
 410                         } else if (len == 2) {
 411                                 if ((filename[0] == '.') && (filename[1] == '.'))
 412                                         rc = 2;
 413                         }
 414                 }
 415         }
 416
 417         return rc;
 418 }
 419
 420 /* Check if directory that we are searching has changed so we can decide
 421    whether we can use the cached search results from the previous search */
 422 static int is_dir_changed(struct file *file)
 423 {
 424         struct inode *inode = file->f_path.dentry->d_inode;
 425         struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
 426
 427         if (cifsInfo->time == 0)
 428                 return 1; /* directory was changed, perhaps due to unlink */
 429         else
 430                 return 0;
 431
 432 }
 433
 434 static int cifs_save_resume_key(const char *current_entry,
 435         struct cifsFileInfo *cifsFile)
 436 {
 437         int rc = 0;
 438         unsigned int len = 0;
 439         __u16 level;
 440         char *filename;
 441
 442         if ((cifsFile == NULL) || (current_entry == NULL))
 443                 return -EINVAL;
 444
 445         level = cifsFile->srch_inf.info_level;
 446
 447         if (level == SMB_FIND_FILE_UNIX) {
 448                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 449
 450                 filename = &pFindData->FileName[0];
 451                 if (cifsFile->srch_inf.unicode) {
 452                         len = cifs_unicode_bytelen(filename);
 453                 } else {
 454                         /* BB should we make this strnlen of PATH_MAX? */
 455                         len = strnlen(filename, PATH_MAX);
 456                 }
 457                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 458         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 459                 FILE_DIRECTORY_INFO *pFindData =
 460                         (FILE_DIRECTORY_INFO *)current_entry;
 461                 filename = &pFindData->FileName[0];
 462                 len = le32_to_cpu(pFindData->FileNameLength);
 463                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 464         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 465                 FILE_FULL_DIRECTORY_INFO *pFindData =
 466                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 467                 filename = &pFindData->FileName[0];
 468                 len = le32_to_cpu(pFindData->FileNameLength);
 469                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 470         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 471                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 472                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 473                 filename = &pFindData->FileName[0];
 474                 len = le32_to_cpu(pFindData->FileNameLength);
 475                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 476         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 477                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 478                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 479                 filename = &pFindData->FileName[0];
 480                 len = le32_to_cpu(pFindData->FileNameLength);
 481                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 482         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 483                 FIND_FILE_STANDARD_INFO *pFindData =
 484                         (FIND_FILE_STANDARD_INFO *)current_entry;
 485                 filename = &pFindData->FileName[0];
 486                 /* one byte length, no name conversion */
 487                 len = (unsigned int)pFindData->FileNameLength;
 488                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 489         } else {
 490                 cFYI(1, "Unknown findfirst level %d", level);
 491                 return -EINVAL;
 492         }
 493         cifsFile->srch_inf.resume_name_len = len;
 494         cifsFile->srch_inf.presume_name = filename;
 495         return rc;
 496 }
 497
 498 /* find the corresponding entry in the search */
 499 /* Note that the SMB server returns search entries for . and .. which
 500    complicates logic here if we choose to parse for them and we do not
 501    assume that they are located in the findfirst return buffer.*/
 502 /* We start counting in the buffer with entry 2 and increment for every
 503    entry (do not increment for . or .. entry) */
 504 static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
 505         struct file *file, char **ppCurrentEntry, int *num_to_ret)
 506 {
 507         int rc = 0;
 508         int pos_in_buf = 0;
 509         loff_t first_entry_in_buffer;
 510         loff_t index_to_find = file->f_pos;
 511         struct cifsFileInfo *cifsFile = file->private_data;
 512         /* check if index in the buffer */
 513
 514         if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
 515            (num_to_ret == NULL))
 516                 return -ENOENT;
 517
 518         *ppCurrentEntry = NULL;
 519         first_entry_in_buffer =
 520                 cifsFile->srch_inf.index_of_last_entry -
 521                         cifsFile->srch_inf.entries_in_buffer;
 522
 523         /* if first entry in buf is zero then is first buffer
 524         in search response data which means it is likely . and ..
 525         will be in this buffer, although some servers do not return
 526         . and .. for the root of a drive and for those we need
 527         to start two entries earlier */
 528
 529         dump_cifs_file_struct(file, "In fce ");
 530         if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
 531              is_dir_changed(file)) ||
 532            (index_to_find < first_entry_in_buffer)) {
 533                 /* close and restart search */
 534                 cFYI(1, "search backing up - close and restart search");
 535                 spin_lock(&cifs_file_list_lock);
 536                 if (!cifsFile->srch_inf.endOfSearch &&
 537                     !cifsFile->invalidHandle) {
 538                         cifsFile->invalidHandle = true;
 539                         spin_unlock(&cifs_file_list_lock);
 540                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 541                 } else
 542                         spin_unlock(&cifs_file_list_lock);
 543                 if (cifsFile->srch_inf.ntwrk_buf_start) {
 544                         cFYI(1, "freeing SMB ff cache buf on search rewind");
 545                         if (cifsFile->srch_inf.smallBuf)
 546                                 cifs_small_buf_release(cifsFile->srch_inf.
 547                                                 ntwrk_buf_start);
 548                         else
 549                                 cifs_buf_release(cifsFile->srch_inf.
 550                                                 ntwrk_buf_start);
 551                         cifsFile->srch_inf.ntwrk_buf_start = NULL;
 552                 }
 553                 rc = initiate_cifs_search(xid, file);
 554                 if (rc) {
 555                         cFYI(1, "error %d reinitiating a search on rewind",
 556                                  rc);
 557                         return rc;
 558                 }
 559                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 560         }
 561
 562         while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
 563               (rc == 0) && !cifsFile->srch_inf.endOfSearch) {
 564                 cFYI(1, "calling findnext2");
 565                 rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
 566                                   &cifsFile->srch_inf);
 567                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 568                 if (rc)
 569                         return -ENOENT;
 570         }
 571         if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
 572                 /* we found the buffer that contains the entry */
 573                 /* scan and find it */
 574                 int i;
 575                 char *current_entry;
 576                 char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
 577                         smbCalcSize((struct smb_hdr *)
 578                                 cifsFile->srch_inf.ntwrk_buf_start);
 579
 580                 current_entry = cifsFile->srch_inf.srch_entries_start;
 581                 first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
 582                                         - cifsFile->srch_inf.entries_in_buffer;
 583                 pos_in_buf = index_to_find - first_entry_in_buffer;
 584                 cFYI(1, "found entry - pos_in_buf %d", pos_in_buf);
 585
 586                 for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
 587                         /* go entry by entry figuring out which is first */
 588                         current_entry = nxt_dir_entry(current_entry, end_of_smb,
 589                                                 cifsFile->srch_inf.info_level);
 590                 }
 591                 if ((current_entry == NULL) && (i < pos_in_buf)) {
 592                         /* BB fixme - check if we should flag this error */
 593                         cERROR(1, "reached end of buf searching for pos in buf"
 594                           " %d index to find %lld rc %d",
 595                           pos_in_buf, index_to_find, rc);
 596                 }
 597                 rc = 0;
 598                 *ppCurrentEntry = current_entry;
 599         } else {
 600                 cFYI(1, "index not in buffer - could not findnext into it");
 601                 return 0;
 602         }
 603
 604         if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
 605                 cFYI(1, "can not return entries pos_in_buf beyond last");
 606                 *num_to_ret = 0;
 607         } else
 608                 *num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
 609
 610         return rc;
 611 }
 612
 613 /* inode num, inode type and filename returned */
 614 static int cifs_get_name_from_search_buf(struct qstr *pqst,
 615         char *current_entry, __u16 level, unsigned int unicode,
 616         struct cifs_sb_info *cifs_sb, unsigned int max_len, __u64 *pinum)
 617 {
 618         int rc = 0;
 619         unsigned int len = 0;
 620         char *filename;
 621         struct nls_table *nlt = cifs_sb->local_nls;
 622
 623         *pinum = 0;
 624
 625         if (level == SMB_FIND_FILE_UNIX) {
 626                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 627
 628                 filename = &pFindData->FileName[0];
 629                 if (unicode) {
 630                         len = cifs_unicode_bytelen(filename);
 631                 } else {
 632                         /* BB should we make this strnlen of PATH_MAX? */
 633                         len = strnlen(filename, PATH_MAX);
 634                 }
 635
 636                 *pinum = le64_to_cpu(pFindData->basic.UniqueId);
 637         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 638                 FILE_DIRECTORY_INFO *pFindData =
 639                         (FILE_DIRECTORY_INFO *)current_entry;
 640                 filename = &pFindData->FileName[0];
 641                 len = le32_to_cpu(pFindData->FileNameLength);
 642         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 643                 FILE_FULL_DIRECTORY_INFO *pFindData =
 644                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 645                 filename = &pFindData->FileName[0];
 646                 len = le32_to_cpu(pFindData->FileNameLength);
 647         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 648                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 649                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 650                 filename = &pFindData->FileName[0];
 651                 len = le32_to_cpu(pFindData->FileNameLength);
 652                 *pinum = le64_to_cpu(pFindData->UniqueId);
 653         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 654                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 655                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 656                 filename = &pFindData->FileName[0];
 657                 len = le32_to_cpu(pFindData->FileNameLength);
 658         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 659                 FIND_FILE_STANDARD_INFO *pFindData =
 660                         (FIND_FILE_STANDARD_INFO *)current_entry;
 661                 filename = &pFindData->FileName[0];
 662                 /* one byte length, no name conversion */
 663                 len = (unsigned int)pFindData->FileNameLength;
 664         } else {
 665                 cFYI(1, "Unknown findfirst level %d", level);
 666                 return -EINVAL;
 667         }
 668
 669         if (len > max_len) {
 670                 cERROR(1, "bad search response length %d past smb end", len);
 671                 return -EINVAL;
 672         }
 673
 674         if (unicode) {
 675                 pqst->len = cifs_from_ucs2((char *) pqst->name,
 676                                            (__le16 *) filename,
 677                                            UNICODE_NAME_MAX,
 678                                            min(len, max_len), nlt,
 679                                            cifs_sb->mnt_cifs_flags &
 680                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 681                 pqst->len -= nls_nullsize(nlt);
 682         } else {
 683                 pqst->name = filename;
 684                 pqst->len = len;
 685         }
 686         return rc;
 687 }
 688
 689 static int cifs_filldir(char *pfindEntry, struct file *file, filldir_t filldir,
 690                         void *direntry, char *scratch_buf, unsigned int max_len)
 691 {
 692         int rc = 0;
 693         struct qstr qstring;
 694         struct cifsFileInfo *pCifsF;
 695         u64    inum;
 696         ino_t  ino;
 697         struct super_block *sb;
 698         struct cifs_sb_info *cifs_sb;
 699         struct dentry *tmp_dentry;
 700         struct cifs_fattr fattr;
 701
 702         /* get filename and len into qstring */
 703         /* get dentry */
 704         /* decide whether to create and populate ionde */
 705         if ((direntry == NULL) || (file == NULL))
 706                 return -EINVAL;
 707
 708         pCifsF = file->private_data;
 709
 710         if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
 711                 return -ENOENT;
 712
 713         rc = cifs_entry_is_dot(pfindEntry, pCifsF);
 714         /* skip . and .. since we added them first */
 715         if (rc != 0)
 716                 return 0;
 717
 718         sb = file->f_path.dentry->d_sb;
 719         cifs_sb = CIFS_SB(sb);
 720
 721         qstring.name = scratch_buf;
 722         rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
 723                         pCifsF->srch_inf.info_level,
 724                         pCifsF->srch_inf.unicode, cifs_sb,
 725                         max_len, &inum /* returned */);
 726
 727         if (rc)
 728                 return rc;
 729
 730         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
 731                 cifs_unix_basic_to_fattr(&fattr,
 732                                  &((FILE_UNIX_INFO *) pfindEntry)->basic,
 733                                  cifs_sb);
 734         else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
 735                 cifs_std_info_to_fattr(&fattr, (FIND_FILE_STANDARD_INFO *)
 736                                         pfindEntry, cifs_sb);
 737         else
 738                 cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)
 739                                         pfindEntry, cifs_sb);
 740
 741         if (inum && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 742                 fattr.cf_uniqueid = inum;
 743         } else {
 744                 fattr.cf_uniqueid = iunique(sb, ROOT_I);
 745                 cifs_autodisable_serverino(cifs_sb);
 746         }
 747
 748         if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
 749             CIFSCouldBeMFSymlink(&fattr))
 750                 /*
 751                  * trying to get the type and mode can be slow,
 752                  * so just call those regular files for now, and mark
 753                  * for reval
 754                  */
 755                 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
 756
 757         ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
 758         tmp_dentry = cifs_readdir_lookup(file->f_dentry, &qstring, &fattr);
 759
 760         rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
 761                      ino, fattr.cf_dtype);
 762
 763         dput(tmp_dentry);
 764         return rc;
 765 }
 766
 767
 768 int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
 769 {
 770         int rc = 0;
 771         int xid, i;
 772         struct cifs_sb_info *cifs_sb;
 773         struct cifsTconInfo *pTcon;
 774         struct cifsFileInfo *cifsFile = NULL;
 775         char *current_entry;
 776         int num_to_fill = 0;
 777         char *tmp_buf = NULL;
 778         char *end_of_smb;
 779         unsigned int max_len;
 780
 781         xid = GetXid();
 782
 783         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 784
 785         /*
 786          * Ensure FindFirst doesn't fail before doing filldir() for '.' and
 787          * '..'. Otherwise we won't be able to notify VFS in case of failure.
 788          */
 789         if (file->private_data == NULL) {
 790                 rc = initiate_cifs_search(xid, file);
 791                 cFYI(1, "initiate cifs search rc %d", rc);
 792                 if (rc)
 793                         goto rddir2_exit;
 794         }
 795
 796         switch ((int) file->f_pos) {
 797         case 0:
 798                 if (filldir(direntry, ".", 1, file->f_pos,
 799                      file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
 800                         cERROR(1, "Filldir for current dir failed");
 801                         rc = -ENOMEM;
 802                         break;
 803                 }
 804                 file->f_pos++;
 805         case 1:
 806                 if (filldir(direntry, "..", 2, file->f_pos,
 807                      file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
 808                         cERROR(1, "Filldir for parent dir failed");
 809                         rc = -ENOMEM;
 810                         break;
 811                 }
 812                 file->f_pos++;
 813         default:
 814                 /* 1) If search is active,
 815                         is in current search buffer?
 816                         if it before then restart search
 817                         if after then keep searching till find it */
 818
 819                 if (file->private_data == NULL) {
 820                         rc = -EINVAL;
 821                         FreeXid(xid);
 822                         return rc;
 823                 }
 824                 cifsFile = file->private_data;
 825                 if (cifsFile->srch_inf.endOfSearch) {
 826                         if (cifsFile->srch_inf.emptyDir) {
 827                                 cFYI(1, "End of search, empty dir");
 828                                 rc = 0;
 829                                 break;
 830                         }
 831                 } /* else {
 832                         cifsFile->invalidHandle = true;
 833                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 834                 } */
 835
 836                 pTcon = tlink_tcon(cifsFile->tlink);
 837                 rc = find_cifs_entry(xid, pTcon, file,
 838                                 &current_entry, &num_to_fill);
 839                 if (rc) {
 840                         cFYI(1, "fce error %d", rc);
 841                         goto rddir2_exit;
 842                 } else if (current_entry != NULL) {
 843                         cFYI(1, "entry %lld found", file->f_pos);
 844                 } else {
 845                         cFYI(1, "could not find entry");
 846                         goto rddir2_exit;
 847                 }
 848                 cFYI(1, "loop through %d times filling dir for net buf %p",
 849                         num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
 850                 max_len = smbCalcSize((struct smb_hdr *)
 851                                 cifsFile->srch_inf.ntwrk_buf_start);
 852                 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
 853
 854                 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
 855                 if (tmp_buf == NULL) {
 856                         rc = -ENOMEM;
 857                         break;
 858                 }
 859
 860                 for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
 861                         if (current_entry == NULL) {
 862                                 /* evaluate whether this case is an error */
 863                                 cERROR(1, "past SMB end,  num to fill %d i %d",
 864                                           num_to_fill, i);
 865                                 break;
 866                         }
 867                         /* if buggy server returns . and .. late do
 868                         we want to check for that here? */
 869                         rc = cifs_filldir(current_entry, file,
 870                                         filldir, direntry, tmp_buf, max_len);
 871                         if (rc == -EOVERFLOW) {
 872                                 rc = 0;
 873                                 break;
 874                         }
 875
 876                         file->f_pos++;
 877                         if (file->f_pos ==
 878                                 cifsFile->srch_inf.index_of_last_entry) {
 879                                 cFYI(1, "last entry in buf at pos %lld %s",
 880                                         file->f_pos, tmp_buf);
 881                                 cifs_save_resume_key(current_entry, cifsFile);
 882                                 break;
 883                         } else
 884                                 current_entry =
 885                                         nxt_dir_entry(current_entry, end_of_smb,
 886                                                 cifsFile->srch_inf.info_level);
 887                 }
 888                 kfree(tmp_buf);
 889                 break;
 890         } /* end switch */
 891
 892 rddir2_exit:
 893         FreeXid(xid);
 894         return rc;
 895 }