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                 inode = dentry->d_inode;
  89                 /* update inode in place if i_ino didn't change */
  90                 if (inode && CIFS_I(inode)->uniqueid == fattr->cf_uniqueid) {
  91                         cifs_fattr_to_inode(inode, fattr);
  92                         return dentry;
  93                 }
  94                 d_drop(dentry);
  95                 dput(dentry);
  96         }
  97
  98         dentry = d_alloc(parent, name);
  99         if (dentry == NULL)
 100                 return NULL;
 101
 102         inode = cifs_iget(sb, fattr);
 103         if (!inode) {
 104                 dput(dentry);
 105                 return NULL;
 106         }
 107
 108         alias = d_materialise_unique(dentry, inode);
 109         if (alias != NULL) {
 110                 dput(dentry);
 111                 if (IS_ERR(alias))
 112                         return NULL;
 113                 dentry = alias;
 114         }
 115
 116         return dentry;
 117 }
 118
 119 static void
 120 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
 121 {
 122         fattr->cf_uid = cifs_sb->mnt_uid;
 123         fattr->cf_gid = cifs_sb->mnt_gid;
 124
 125         if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
 126                 fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
 127                 fattr->cf_dtype = DT_DIR;
 128         } else {
 129                 fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
 130                 fattr->cf_dtype = DT_REG;
 131         }
 132
 133         if (fattr->cf_cifsattrs & ATTR_READONLY)
 134                 fattr->cf_mode &= ~S_IWUGO;
 135
 136         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
 137             fattr->cf_cifsattrs & ATTR_SYSTEM) {
 138                 if (fattr->cf_eof == 0)  {
 139                         fattr->cf_mode &= ~S_IFMT;
 140                         fattr->cf_mode |= S_IFIFO;
 141                         fattr->cf_dtype = DT_FIFO;
 142                 } else {
 143                         /*
 144                          * trying to get the type and mode via SFU can be slow,
 145                          * so just call those regular files for now, and mark
 146                          * for reval
 147                          */
 148                         fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
 149                 }
 150         }
 151 }
 152
 153 static void
 154 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
 155                        struct cifs_sb_info *cifs_sb)
 156 {
 157         memset(fattr, 0, sizeof(*fattr));
 158         fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
 159         fattr->cf_eof = le64_to_cpu(info->EndOfFile);
 160         fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
 161         fattr->cf_createtime = le64_to_cpu(info->CreationTime);
 162         fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
 163         fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
 164         fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
 165
 166         cifs_fill_common_info(fattr, cifs_sb);
 167 }
 168
 169 static void
 170 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
 171                        struct cifs_sb_info *cifs_sb)
 172 {
 173         int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
 174
 175         memset(fattr, 0, sizeof(*fattr));
 176         fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
 177                                             info->LastAccessTime, offset);
 178         fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
 179                                             info->LastWriteTime, offset);
 180         fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
 181                                             info->LastWriteTime, offset);
 182
 183         fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
 184         fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
 185         fattr->cf_eof = le32_to_cpu(info->DataSize);
 186
 187         cifs_fill_common_info(fattr, cifs_sb);
 188 }
 189
 190 /* BB eventually need to add the following helper function to
 191       resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
 192       we try to do FindFirst on (NTFS) directory symlinks */
 193 /*
 194 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
 195                              int xid)
 196 {
 197         __u16 fid;
 198         int len;
 199         int oplock = 0;
 200         int rc;
 201         struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
 202         char *tmpbuffer;
 203
 204         rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
 205                         OPEN_REPARSE_POINT, &fid, &oplock, NULL,
 206                         cifs_sb->local_nls,
 207                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 208         if (!rc) {
 209                 tmpbuffer = kmalloc(maxpath);
 210                 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
 211                                 tmpbuffer,
 212                                 maxpath -1,
 213                                 fid,
 214                                 cifs_sb->local_nls);
 215                 if (CIFSSMBClose(xid, ptcon, fid)) {
 216                         cFYI(1, "Error closing temporary reparsepoint open");
 217                 }
 218         }
 219 }
 220  */
 221
 222 static int initiate_cifs_search(const int xid, struct file *file)
 223 {
 224         int rc = 0;
 225         char *full_path = NULL;
 226         struct cifsFileInfo *cifsFile;
 227         struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 228         struct tcon_link *tlink = NULL;
 229         struct cifs_tcon *pTcon;
 230
 231         if (file->private_data == NULL) {
 232                 tlink = cifs_sb_tlink(cifs_sb);
 233                 if (IS_ERR(tlink))
 234                         return PTR_ERR(tlink);
 235
 236                 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
 237                 if (cifsFile == NULL) {
 238                         rc = -ENOMEM;
 239                         goto error_exit;
 240                 }
 241                 file->private_data = cifsFile;
 242                 cifsFile->tlink = cifs_get_tlink(tlink);
 243                 pTcon = tlink_tcon(tlink);
 244         } else {
 245                 cifsFile = file->private_data;
 246                 pTcon = tlink_tcon(cifsFile->tlink);
 247         }
 248
 249         cifsFile->invalidHandle = true;
 250         cifsFile->srch_inf.endOfSearch = false;
 251
 252         full_path = build_path_from_dentry(file->f_path.dentry);
 253         if (full_path == NULL) {
 254                 rc = -ENOMEM;
 255                 goto error_exit;
 256         }
 257
 258         cFYI(1, "Full path: %s start at: %lld", full_path, file->f_pos);
 259
 260 ffirst_retry:
 261         /* test for Unix extensions */
 262         /* but now check for them on the share/mount not on the SMB session */
 263 /*      if (pTcon->ses->capabilities & CAP_UNIX) { */
 264         if (pTcon->unix_ext)
 265                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
 266         else if ((pTcon->ses->capabilities &
 267                         (CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
 268                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
 269         } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
 270                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
 271         } else /* not srvinos - BB fixme add check for backlevel? */ {
 272                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
 273         }
 274
 275         rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
 276                 &cifsFile->netfid, &cifsFile->srch_inf,
 277                 cifs_sb->mnt_cifs_flags &
 278                         CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
 279         if (rc == 0)
 280                 cifsFile->invalidHandle = false;
 281         /* BB add following call to handle readdir on new NTFS symlink errors
 282         else if STATUS_STOPPED_ON_SYMLINK
 283                 call get_symlink_reparse_path and retry with new path */
 284         else if ((rc == -EOPNOTSUPP) &&
 285                 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 286                 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
 287                 goto ffirst_retry;
 288         }
 289 error_exit:
 290         kfree(full_path);
 291         cifs_put_tlink(tlink);
 292         return rc;
 293 }
 294
 295 /* return length of unicode string in bytes */
 296 static int cifs_unicode_bytelen(char *str)
 297 {
 298         int len;
 299         __le16 *ustr = (__le16 *)str;
 300
 301         for (len = 0; len <= PATH_MAX; len++) {
 302                 if (ustr[len] == 0)
 303                         return len << 1;
 304         }
 305         cFYI(1, "Unicode string longer than PATH_MAX found");
 306         return len << 1;
 307 }
 308
 309 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
 310 {
 311         char *new_entry;
 312         FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
 313
 314         if (level == SMB_FIND_FILE_INFO_STANDARD) {
 315                 FIND_FILE_STANDARD_INFO *pfData;
 316                 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
 317
 318                 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
 319                                 pfData->FileNameLength;
 320         } else
 321                 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
 322         cFYI(1, "new entry %p old entry %p", new_entry, old_entry);
 323         /* validate that new_entry is not past end of SMB */
 324         if (new_entry >= end_of_smb) {
 325                 cERROR(1, "search entry %p began after end of SMB %p old entry %p",
 326                         new_entry, end_of_smb, old_entry);
 327                 return NULL;
 328         } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
 329                     (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
 330                   || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
 331                    (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
 332                 cERROR(1, "search entry %p extends after end of SMB %p",
 333                         new_entry, end_of_smb);
 334                 return NULL;
 335         } else
 336                 return new_entry;
 337
 338 }
 339
 340 #define UNICODE_DOT cpu_to_le16(0x2e)
 341
 342 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
 343 static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
 344 {
 345         int rc = 0;
 346         char *filename = NULL;
 347         int len = 0;
 348
 349         if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
 350                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 351                 filename = &pFindData->FileName[0];
 352                 if (cfile->srch_inf.unicode) {
 353                         len = cifs_unicode_bytelen(filename);
 354                 } else {
 355                         /* BB should we make this strnlen of PATH_MAX? */
 356                         len = strnlen(filename, 5);
 357                 }
 358         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
 359                 FILE_DIRECTORY_INFO *pFindData =
 360                         (FILE_DIRECTORY_INFO *)current_entry;
 361                 filename = &pFindData->FileName[0];
 362                 len = le32_to_cpu(pFindData->FileNameLength);
 363         } else if (cfile->srch_inf.info_level ==
 364                         SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 365                 FILE_FULL_DIRECTORY_INFO *pFindData =
 366                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 367                 filename = &pFindData->FileName[0];
 368                 len = le32_to_cpu(pFindData->FileNameLength);
 369         } else if (cfile->srch_inf.info_level ==
 370                         SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 371                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 372                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 373                 filename = &pFindData->FileName[0];
 374                 len = le32_to_cpu(pFindData->FileNameLength);
 375         } else if (cfile->srch_inf.info_level ==
 376                         SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 377                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 378                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 379                 filename = &pFindData->FileName[0];
 380                 len = le32_to_cpu(pFindData->FileNameLength);
 381         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
 382                 FIND_FILE_STANDARD_INFO *pFindData =
 383                         (FIND_FILE_STANDARD_INFO *)current_entry;
 384                 filename = &pFindData->FileName[0];
 385                 len = pFindData->FileNameLength;
 386         } else {
 387                 cFYI(1, "Unknown findfirst level %d",
 388                          cfile->srch_inf.info_level);
 389         }
 390
 391         if (filename) {
 392                 if (cfile->srch_inf.unicode) {
 393                         __le16 *ufilename = (__le16 *)filename;
 394                         if (len == 2) {
 395                                 /* check for . */
 396                                 if (ufilename[0] == UNICODE_DOT)
 397                                         rc = 1;
 398                         } else if (len == 4) {
 399                                 /* check for .. */
 400                                 if ((ufilename[0] == UNICODE_DOT)
 401                                    && (ufilename[1] == UNICODE_DOT))
 402                                         rc = 2;
 403                         }
 404                 } else /* ASCII */ {
 405                         if (len == 1) {
 406                                 if (filename[0] == '.')
 407                                         rc = 1;
 408                         } else if (len == 2) {
 409                                 if ((filename[0] == '.') && (filename[1] == '.'))
 410                                         rc = 2;
 411                         }
 412                 }
 413         }
 414
 415         return rc;
 416 }
 417
 418 /* Check if directory that we are searching has changed so we can decide
 419    whether we can use the cached search results from the previous search */
 420 static int is_dir_changed(struct file *file)
 421 {
 422         struct inode *inode = file->f_path.dentry->d_inode;
 423         struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
 424
 425         if (cifsInfo->time == 0)
 426                 return 1; /* directory was changed, perhaps due to unlink */
 427         else
 428                 return 0;
 429
 430 }
 431
 432 static int cifs_save_resume_key(const char *current_entry,
 433         struct cifsFileInfo *cifsFile)
 434 {
 435         int rc = 0;
 436         unsigned int len = 0;
 437         __u16 level;
 438         char *filename;
 439
 440         if ((cifsFile == NULL) || (current_entry == NULL))
 441                 return -EINVAL;
 442
 443         level = cifsFile->srch_inf.info_level;
 444
 445         if (level == SMB_FIND_FILE_UNIX) {
 446                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 447
 448                 filename = &pFindData->FileName[0];
 449                 if (cifsFile->srch_inf.unicode) {
 450                         len = cifs_unicode_bytelen(filename);
 451                 } else {
 452                         /* BB should we make this strnlen of PATH_MAX? */
 453                         len = strnlen(filename, PATH_MAX);
 454                 }
 455                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 456         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 457                 FILE_DIRECTORY_INFO *pFindData =
 458                         (FILE_DIRECTORY_INFO *)current_entry;
 459                 filename = &pFindData->FileName[0];
 460                 len = le32_to_cpu(pFindData->FileNameLength);
 461                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 462         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 463                 FILE_FULL_DIRECTORY_INFO *pFindData =
 464                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 465                 filename = &pFindData->FileName[0];
 466                 len = le32_to_cpu(pFindData->FileNameLength);
 467                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 468         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 469                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 470                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 471                 filename = &pFindData->FileName[0];
 472                 len = le32_to_cpu(pFindData->FileNameLength);
 473                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 474         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 475                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 476                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 477                 filename = &pFindData->FileName[0];
 478                 len = le32_to_cpu(pFindData->FileNameLength);
 479                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 480         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 481                 FIND_FILE_STANDARD_INFO *pFindData =
 482                         (FIND_FILE_STANDARD_INFO *)current_entry;
 483                 filename = &pFindData->FileName[0];
 484                 /* one byte length, no name conversion */
 485                 len = (unsigned int)pFindData->FileNameLength;
 486                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 487         } else {
 488                 cFYI(1, "Unknown findfirst level %d", level);
 489                 return -EINVAL;
 490         }
 491         cifsFile->srch_inf.resume_name_len = len;
 492         cifsFile->srch_inf.presume_name = filename;
 493         return rc;
 494 }
 495
 496 /* find the corresponding entry in the search */
 497 /* Note that the SMB server returns search entries for . and .. which
 498    complicates logic here if we choose to parse for them and we do not
 499    assume that they are located in the findfirst return buffer.*/
 500 /* We start counting in the buffer with entry 2 and increment for every
 501    entry (do not increment for . or .. entry) */
 502 static int find_cifs_entry(const int xid, struct cifs_tcon *pTcon,
 503         struct file *file, char **ppCurrentEntry, int *num_to_ret)
 504 {
 505         int rc = 0;
 506         int pos_in_buf = 0;
 507         loff_t first_entry_in_buffer;
 508         loff_t index_to_find = file->f_pos;
 509         struct cifsFileInfo *cifsFile = file->private_data;
 510         /* check if index in the buffer */
 511
 512         if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
 513            (num_to_ret == NULL))
 514                 return -ENOENT;
 515
 516         *ppCurrentEntry = NULL;
 517         first_entry_in_buffer =
 518                 cifsFile->srch_inf.index_of_last_entry -
 519                         cifsFile->srch_inf.entries_in_buffer;
 520
 521         /* if first entry in buf is zero then is first buffer
 522         in search response data which means it is likely . and ..
 523         will be in this buffer, although some servers do not return
 524         . and .. for the root of a drive and for those we need
 525         to start two entries earlier */
 526
 527         dump_cifs_file_struct(file, "In fce ");
 528         if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
 529              is_dir_changed(file)) ||
 530            (index_to_find < first_entry_in_buffer)) {
 531                 /* close and restart search */
 532                 cFYI(1, "search backing up - close and restart search");
 533                 spin_lock(&cifs_file_list_lock);
 534                 if (!cifsFile->srch_inf.endOfSearch &&
 535                     !cifsFile->invalidHandle) {
 536                         cifsFile->invalidHandle = true;
 537                         spin_unlock(&cifs_file_list_lock);
 538                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 539                 } else
 540                         spin_unlock(&cifs_file_list_lock);
 541                 if (cifsFile->srch_inf.ntwrk_buf_start) {
 542                         cFYI(1, "freeing SMB ff cache buf on search rewind");
 543                         if (cifsFile->srch_inf.smallBuf)
 544                                 cifs_small_buf_release(cifsFile->srch_inf.
 545                                                 ntwrk_buf_start);
 546                         else
 547                                 cifs_buf_release(cifsFile->srch_inf.
 548                                                 ntwrk_buf_start);
 549                         cifsFile->srch_inf.ntwrk_buf_start = NULL;
 550                 }
 551                 rc = initiate_cifs_search(xid, file);
 552                 if (rc) {
 553                         cFYI(1, "error %d reinitiating a search on rewind",
 554                                  rc);
 555                         return rc;
 556                 }
 557                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 558         }
 559
 560         while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
 561               (rc == 0) && !cifsFile->srch_inf.endOfSearch) {
 562                 cFYI(1, "calling findnext2");
 563                 rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
 564                                   &cifsFile->srch_inf);
 565                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 566                 if (rc)
 567                         return -ENOENT;
 568         }
 569         if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
 570                 /* we found the buffer that contains the entry */
 571                 /* scan and find it */
 572                 int i;
 573                 char *current_entry;
 574                 char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
 575                         smbCalcSize((struct smb_hdr *)
 576                                 cifsFile->srch_inf.ntwrk_buf_start);
 577
 578                 current_entry = cifsFile->srch_inf.srch_entries_start;
 579                 first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
 580                                         - cifsFile->srch_inf.entries_in_buffer;
 581                 pos_in_buf = index_to_find - first_entry_in_buffer;
 582                 cFYI(1, "found entry - pos_in_buf %d", pos_in_buf);
 583
 584                 for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
 585                         /* go entry by entry figuring out which is first */
 586                         current_entry = nxt_dir_entry(current_entry, end_of_smb,
 587                                                 cifsFile->srch_inf.info_level);
 588                 }
 589                 if ((current_entry == NULL) && (i < pos_in_buf)) {
 590                         /* BB fixme - check if we should flag this error */
 591                         cERROR(1, "reached end of buf searching for pos in buf"
 592                           " %d index to find %lld rc %d",
 593                           pos_in_buf, index_to_find, rc);
 594                 }
 595                 rc = 0;
 596                 *ppCurrentEntry = current_entry;
 597         } else {
 598                 cFYI(1, "index not in buffer - could not findnext into it");
 599                 return 0;
 600         }
 601
 602         if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
 603                 cFYI(1, "can not return entries pos_in_buf beyond last");
 604                 *num_to_ret = 0;
 605         } else
 606                 *num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
 607
 608         return rc;
 609 }
 610
 611 /* inode num, inode type and filename returned */
 612 static int cifs_get_name_from_search_buf(struct qstr *pqst,
 613         char *current_entry, __u16 level, unsigned int unicode,
 614         struct cifs_sb_info *cifs_sb, unsigned int max_len, __u64 *pinum)
 615 {
 616         int rc = 0;
 617         unsigned int len = 0;
 618         char *filename;
 619         struct nls_table *nlt = cifs_sb->local_nls;
 620
 621         *pinum = 0;
 622
 623         if (level == SMB_FIND_FILE_UNIX) {
 624                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 625
 626                 filename = &pFindData->FileName[0];
 627                 if (unicode) {
 628                         len = cifs_unicode_bytelen(filename);
 629                 } else {
 630                         /* BB should we make this strnlen of PATH_MAX? */
 631                         len = strnlen(filename, PATH_MAX);
 632                 }
 633
 634                 *pinum = le64_to_cpu(pFindData->basic.UniqueId);
 635         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 636                 FILE_DIRECTORY_INFO *pFindData =
 637                         (FILE_DIRECTORY_INFO *)current_entry;
 638                 filename = &pFindData->FileName[0];
 639                 len = le32_to_cpu(pFindData->FileNameLength);
 640         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 641                 FILE_FULL_DIRECTORY_INFO *pFindData =
 642                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 643                 filename = &pFindData->FileName[0];
 644                 len = le32_to_cpu(pFindData->FileNameLength);
 645         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 646                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 647                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 648                 filename = &pFindData->FileName[0];
 649                 len = le32_to_cpu(pFindData->FileNameLength);
 650                 *pinum = le64_to_cpu(pFindData->UniqueId);
 651         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 652                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 653                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 654                 filename = &pFindData->FileName[0];
 655                 len = le32_to_cpu(pFindData->FileNameLength);
 656         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 657                 FIND_FILE_STANDARD_INFO *pFindData =
 658                         (FIND_FILE_STANDARD_INFO *)current_entry;
 659                 filename = &pFindData->FileName[0];
 660                 /* one byte length, no name conversion */
 661                 len = (unsigned int)pFindData->FileNameLength;
 662         } else {
 663                 cFYI(1, "Unknown findfirst level %d", level);
 664                 return -EINVAL;
 665         }
 666
 667         if (len > max_len) {
 668                 cERROR(1, "bad search response length %d past smb end", len);
 669                 return -EINVAL;
 670         }
 671
 672         if (unicode) {
 673                 pqst->len = cifs_from_ucs2((char *) pqst->name,
 674                                            (__le16 *) filename,
 675                                            UNICODE_NAME_MAX,
 676                                            min(len, max_len), nlt,
 677                                            cifs_sb->mnt_cifs_flags &
 678                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 679                 pqst->len -= nls_nullsize(nlt);
 680         } else {
 681                 pqst->name = filename;
 682                 pqst->len = len;
 683         }
 684         return rc;
 685 }
 686
 687 static int cifs_filldir(char *pfindEntry, struct file *file, filldir_t filldir,
 688                         void *direntry, char *scratch_buf, unsigned int max_len)
 689 {
 690         int rc = 0;
 691         struct qstr qstring;
 692         struct cifsFileInfo *pCifsF;
 693         u64    inum;
 694         ino_t  ino;
 695         struct super_block *sb;
 696         struct cifs_sb_info *cifs_sb;
 697         struct dentry *tmp_dentry;
 698         struct cifs_fattr fattr;
 699
 700         /* get filename and len into qstring */
 701         /* get dentry */
 702         /* decide whether to create and populate ionde */
 703         if ((direntry == NULL) || (file == NULL))
 704                 return -EINVAL;
 705
 706         pCifsF = file->private_data;
 707
 708         if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
 709                 return -ENOENT;
 710
 711         rc = cifs_entry_is_dot(pfindEntry, pCifsF);
 712         /* skip . and .. since we added them first */
 713         if (rc != 0)
 714                 return 0;
 715
 716         sb = file->f_path.dentry->d_sb;
 717         cifs_sb = CIFS_SB(sb);
 718
 719         qstring.name = scratch_buf;
 720         rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
 721                         pCifsF->srch_inf.info_level,
 722                         pCifsF->srch_inf.unicode, cifs_sb,
 723                         max_len, &inum /* returned */);
 724
 725         if (rc)
 726                 return rc;
 727
 728         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
 729                 cifs_unix_basic_to_fattr(&fattr,
 730                                  &((FILE_UNIX_INFO *) pfindEntry)->basic,
 731                                  cifs_sb);
 732         else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
 733                 cifs_std_info_to_fattr(&fattr, (FIND_FILE_STANDARD_INFO *)
 734                                         pfindEntry, cifs_sb);
 735         else
 736                 cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)
 737                                         pfindEntry, cifs_sb);
 738
 739         if (inum && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 740                 fattr.cf_uniqueid = inum;
 741         } else {
 742                 fattr.cf_uniqueid = iunique(sb, ROOT_I);
 743                 cifs_autodisable_serverino(cifs_sb);
 744         }
 745
 746         if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
 747             CIFSCouldBeMFSymlink(&fattr))
 748                 /*
 749                  * trying to get the type and mode can be slow,
 750                  * so just call those regular files for now, and mark
 751                  * for reval
 752                  */
 753                 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
 754
 755         ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
 756         tmp_dentry = cifs_readdir_lookup(file->f_dentry, &qstring, &fattr);
 757
 758         rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
 759                      ino, fattr.cf_dtype);
 760
 761         dput(tmp_dentry);
 762         return rc;
 763 }
 764
 765
 766 int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
 767 {
 768         int rc = 0;
 769         int xid, i;
 770         struct cifs_tcon *pTcon;
 771         struct cifsFileInfo *cifsFile = NULL;
 772         char *current_entry;
 773         int num_to_fill = 0;
 774         char *tmp_buf = NULL;
 775         char *end_of_smb;
 776         unsigned int max_len;
 777
 778         xid = GetXid();
 779
 780         /*
 781          * Ensure FindFirst doesn't fail before doing filldir() for '.' and
 782          * '..'. Otherwise we won't be able to notify VFS in case of failure.
 783          */
 784         if (file->private_data == NULL) {
 785                 rc = initiate_cifs_search(xid, file);
 786                 cFYI(1, "initiate cifs search rc %d", rc);
 787                 if (rc)
 788                         goto rddir2_exit;
 789         }
 790
 791         switch ((int) file->f_pos) {
 792         case 0:
 793                 if (filldir(direntry, ".", 1, file->f_pos,
 794                      file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
 795                         cERROR(1, "Filldir for current dir failed");
 796                         rc = -ENOMEM;
 797                         break;
 798                 }
 799                 file->f_pos++;
 800         case 1:
 801                 if (filldir(direntry, "..", 2, file->f_pos,
 802                      file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
 803                         cERROR(1, "Filldir for parent dir failed");
 804                         rc = -ENOMEM;
 805                         break;
 806                 }
 807                 file->f_pos++;
 808         default:
 809                 /* 1) If search is active,
 810                         is in current search buffer?
 811                         if it before then restart search
 812                         if after then keep searching till find it */
 813
 814                 if (file->private_data == NULL) {
 815                         rc = -EINVAL;
 816                         FreeXid(xid);
 817                         return rc;
 818                 }
 819                 cifsFile = file->private_data;
 820                 if (cifsFile->srch_inf.endOfSearch) {
 821                         if (cifsFile->srch_inf.emptyDir) {
 822                                 cFYI(1, "End of search, empty dir");
 823                                 rc = 0;
 824                                 break;
 825                         }
 826                 } /* else {
 827                         cifsFile->invalidHandle = true;
 828                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 829                 } */
 830
 831                 pTcon = tlink_tcon(cifsFile->tlink);
 832                 rc = find_cifs_entry(xid, pTcon, file,
 833                                 &current_entry, &num_to_fill);
 834                 if (rc) {
 835                         cFYI(1, "fce error %d", rc);
 836                         goto rddir2_exit;
 837                 } else if (current_entry != NULL) {
 838                         cFYI(1, "entry %lld found", file->f_pos);
 839                 } else {
 840                         cFYI(1, "could not find entry");
 841                         goto rddir2_exit;
 842                 }
 843                 cFYI(1, "loop through %d times filling dir for net buf %p",
 844                         num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
 845                 max_len = smbCalcSize((struct smb_hdr *)
 846                                 cifsFile->srch_inf.ntwrk_buf_start);
 847                 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
 848
 849                 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
 850                 if (tmp_buf == NULL) {
 851                         rc = -ENOMEM;
 852                         break;
 853                 }
 854
 855                 for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
 856                         if (current_entry == NULL) {
 857                                 /* evaluate whether this case is an error */
 858                                 cERROR(1, "past SMB end,  num to fill %d i %d",
 859                                           num_to_fill, i);
 860                                 break;
 861                         }
 862                         /* if buggy server returns . and .. late do
 863                         we want to check for that here? */
 864                         rc = cifs_filldir(current_entry, file,
 865                                         filldir, direntry, tmp_buf, max_len);
 866                         if (rc == -EOVERFLOW) {
 867                                 rc = 0;
 868                                 break;
 869                         }
 870
 871                         file->f_pos++;
 872                         if (file->f_pos ==
 873                                 cifsFile->srch_inf.index_of_last_entry) {
 874                                 cFYI(1, "last entry in buf at pos %lld %s",
 875                                         file->f_pos, tmp_buf);
 876                                 cifs_save_resume_key(current_entry, cifsFile);
 877                                 break;
 878                         } else
 879                                 current_entry =
 880                                         nxt_dir_entry(current_entry, end_of_smb,
 881                                                 cifsFile->srch_inf.info_level);
 882                 }
 883                 kfree(tmp_buf);
 884                 break;
 885         } /* end switch */
 886
 887 rddir2_exit:
 888         FreeXid(xid);
 889         return rc;
 890 }