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/stat.h>
  26 #include "cifspdu.h"
  27 #include "cifsglob.h"
  28 #include "cifsproto.h"
  29 #include "cifs_unicode.h"
  30 #include "cifs_debug.h"
  31 #include "cifs_fs_sb.h"
  32 #include "cifsfs.h"
  33
  34 /*
  35  * To be safe - for UCS to UTF-8 with strings loaded with the rare long
  36  * characters alloc more to account for such multibyte target UTF-8
  37  * characters.
  38  */
  39 #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
  40
  41 #ifdef CONFIG_CIFS_DEBUG2
  42 static void dump_cifs_file_struct(struct file *file, char *label)
  43 {
  44         struct cifsFileInfo *cf;
  45
  46         if (file) {
  47                 cf = file->private_data;
  48                 if (cf == NULL) {
  49                         cFYI(1, ("empty cifs private file data"));
  50                         return;
  51                 }
  52                 if (cf->invalidHandle)
  53                         cFYI(1, ("invalid handle"));
  54                 if (cf->srch_inf.endOfSearch)
  55                         cFYI(1, ("end of search"));
  56                 if (cf->srch_inf.emptyDir)
  57                         cFYI(1, ("empty dir"));
  58         }
  59 }
  60 #else
  61 static inline void dump_cifs_file_struct(struct file *file, char *label)
  62 {
  63 }
  64 #endif /* DEBUG2 */
  65
  66 /* Returns 1 if new inode created, 2 if both dentry and inode were */
  67 /* Might check in the future if inode number changed so we can rehash inode */
  68 static int
  69 construct_dentry(struct qstr *qstring, struct file *file,
  70                  struct inode **ptmp_inode, struct dentry **pnew_dentry,
  71                  __u64 *inum)
  72 {
  73         struct dentry *tmp_dentry = NULL;
  74         struct super_block *sb = file->f_path.dentry->d_sb;
  75         int rc = 0;
  76
  77         cFYI(1, ("For %s", qstring->name));
  78
  79         qstring->hash = full_name_hash(qstring->name, qstring->len);
  80         tmp_dentry = d_lookup(file->f_path.dentry, qstring);
  81         if (tmp_dentry) {
  82                 /* BB: overwrite old name? i.e. tmp_dentry->d_name and
  83                  * tmp_dentry->d_name.len??
  84                  */
  85                 cFYI(0, ("existing dentry with inode 0x%p",
  86                          tmp_dentry->d_inode));
  87                 *ptmp_inode = tmp_dentry->d_inode;
  88                 if (*ptmp_inode == NULL) {
  89                         *ptmp_inode = cifs_new_inode(sb, inum);
  90                         if (*ptmp_inode == NULL)
  91                                 return rc;
  92                         rc = 1;
  93                 }
  94         } else {
  95                 tmp_dentry = d_alloc(file->f_path.dentry, qstring);
  96                 if (tmp_dentry == NULL) {
  97                         cERROR(1, ("Failed allocating dentry"));
  98                         *ptmp_inode = NULL;
  99                         return rc;
 100                 }
 101
 102                 if (CIFS_SB(sb)->tcon->nocase)
 103                         tmp_dentry->d_op = &cifs_ci_dentry_ops;
 104                 else
 105                         tmp_dentry->d_op = &cifs_dentry_ops;
 106
 107                 *ptmp_inode = cifs_new_inode(sb, inum);
 108                 if (*ptmp_inode == NULL)
 109                         return rc;
 110                 rc = 2;
 111         }
 112
 113         tmp_dentry->d_time = jiffies;
 114         *pnew_dentry = tmp_dentry;
 115         return rc;
 116 }
 117
 118 static void fill_in_inode(struct inode *tmp_inode, int new_buf_type,
 119                           char *buf, unsigned int *pobject_type, int isNewInode)
 120 {
 121         loff_t local_size;
 122         struct timespec local_mtime;
 123
 124         struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
 125         struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
 126         __u32 attr;
 127         __u64 allocation_size;
 128         __u64 end_of_file;
 129         umode_t default_mode;
 130
 131         /* save mtime and size */
 132         local_mtime = tmp_inode->i_mtime;
 133         local_size  = tmp_inode->i_size;
 134
 135         if (new_buf_type) {
 136                 FILE_DIRECTORY_INFO *pfindData = (FILE_DIRECTORY_INFO *)buf;
 137
 138                 attr = le32_to_cpu(pfindData->ExtFileAttributes);
 139                 allocation_size = le64_to_cpu(pfindData->AllocationSize);
 140                 end_of_file = le64_to_cpu(pfindData->EndOfFile);
 141                 tmp_inode->i_atime =
 142                         cifs_NTtimeToUnix(pfindData->LastAccessTime);
 143                 tmp_inode->i_mtime =
 144                         cifs_NTtimeToUnix(pfindData->LastWriteTime);
 145                 tmp_inode->i_ctime =
 146                         cifs_NTtimeToUnix(pfindData->ChangeTime);
 147         } else { /* legacy, OS2 and DOS style */
 148                 int offset = cifs_sb->tcon->ses->server->timeAdj;
 149                 FIND_FILE_STANDARD_INFO *pfindData =
 150                         (FIND_FILE_STANDARD_INFO *)buf;
 151
 152                 tmp_inode->i_mtime = cnvrtDosUnixTm(pfindData->LastWriteDate,
 153                                                     pfindData->LastWriteTime,
 154                                                     offset);
 155                 tmp_inode->i_atime = cnvrtDosUnixTm(pfindData->LastAccessDate,
 156                                                     pfindData->LastAccessTime,
 157                                                     offset);
 158                 tmp_inode->i_ctime = cnvrtDosUnixTm(pfindData->LastWriteDate,
 159                                                     pfindData->LastWriteTime,
 160                                                     offset);
 161                 attr = le16_to_cpu(pfindData->Attributes);
 162                 allocation_size = le32_to_cpu(pfindData->AllocationSize);
 163                 end_of_file = le32_to_cpu(pfindData->DataSize);
 164         }
 165
 166         /* Linux can not store file creation time unfortunately so ignore it */
 167
 168         cifsInfo->cifsAttrs = attr;
 169 #ifdef CONFIG_CIFS_EXPERIMENTAL
 170         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) {
 171                 /* get more accurate mode via ACL - so force inode refresh */
 172                 cifsInfo->time = 0;
 173         } else
 174 #endif /* CONFIG_CIFS_EXPERIMENTAL */
 175                 cifsInfo->time = jiffies;
 176
 177         /* treat dos attribute of read-only as read-only mode bit e.g. 555? */
 178         /* 2767 perms - indicate mandatory locking */
 179                 /* BB fill in uid and gid here? with help from winbind?
 180                    or retrieve from NTFS stream extended attribute */
 181         if (atomic_read(&cifsInfo->inUse) == 0) {
 182                 tmp_inode->i_uid = cifs_sb->mnt_uid;
 183                 tmp_inode->i_gid = cifs_sb->mnt_gid;
 184         }
 185
 186         if (attr & ATTR_DIRECTORY)
 187                 default_mode = cifs_sb->mnt_dir_mode;
 188         else
 189                 default_mode = cifs_sb->mnt_file_mode;
 190
 191         /* set initial permissions */
 192         if ((atomic_read(&cifsInfo->inUse) == 0) ||
 193             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM) == 0)
 194                 tmp_inode->i_mode = default_mode;
 195         else {
 196                 /* just reenable write bits if !ATTR_READONLY */
 197                 if ((tmp_inode->i_mode & S_IWUGO) == 0 &&
 198                     (attr & ATTR_READONLY) == 0)
 199                         tmp_inode->i_mode |= (S_IWUGO & default_mode);
 200
 201                 tmp_inode->i_mode &= ~S_IFMT;
 202         }
 203
 204         /* clear write bits if ATTR_READONLY is set */
 205         if (attr & ATTR_READONLY)
 206                 tmp_inode->i_mode &= ~S_IWUGO;
 207
 208         /* set inode type */
 209         if ((attr & ATTR_SYSTEM) &&
 210             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL)) {
 211                 if (end_of_file == 0)  {
 212                         tmp_inode->i_mode |= S_IFIFO;
 213                         *pobject_type = DT_FIFO;
 214                 } else {
 215                         /*
 216                          * trying to get the type can be slow, so just call
 217                          * this a regular file for now, and mark for reval
 218                          */
 219                         tmp_inode->i_mode |= S_IFREG;
 220                         *pobject_type = DT_REG;
 221                         cifsInfo->time = 0;
 222                 }
 223         } else {
 224                 if (attr & ATTR_DIRECTORY) {
 225                         tmp_inode->i_mode |= S_IFDIR;
 226                         *pobject_type = DT_DIR;
 227                 } else {
 228                         tmp_inode->i_mode |= S_IFREG;
 229                         *pobject_type = DT_REG;
 230                 }
 231         }
 232
 233         /* can not fill in nlink here as in qpathinfo version and Unx search */
 234         if (atomic_read(&cifsInfo->inUse) == 0)
 235                 atomic_set(&cifsInfo->inUse, 1);
 236
 237         cifsInfo->server_eof = end_of_file;
 238         spin_lock(&tmp_inode->i_lock);
 239         if (is_size_safe_to_change(cifsInfo, end_of_file)) {
 240                 /* can not safely change the file size here if the
 241                 client is writing to it due to potential races */
 242                 i_size_write(tmp_inode, end_of_file);
 243
 244         /* 512 bytes (2**9) is the fake blocksize that must be used */
 245         /* for this calculation, even though the reported blocksize is larger */
 246                 tmp_inode->i_blocks = (512 - 1 + allocation_size) >> 9;
 247         }
 248         spin_unlock(&tmp_inode->i_lock);
 249
 250         if (allocation_size < end_of_file)
 251                 cFYI(1, ("May be sparse file, allocation less than file size"));
 252         cFYI(1, ("File Size %ld and blocks %llu",
 253                 (unsigned long)tmp_inode->i_size,
 254                 (unsigned long long)tmp_inode->i_blocks));
 255         if (S_ISREG(tmp_inode->i_mode)) {
 256                 cFYI(1, ("File inode"));
 257                 tmp_inode->i_op = &cifs_file_inode_ops;
 258                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
 259                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 260                                 tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
 261                         else
 262                                 tmp_inode->i_fop = &cifs_file_direct_ops;
 263                 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 264                         tmp_inode->i_fop = &cifs_file_nobrl_ops;
 265                 else
 266                         tmp_inode->i_fop = &cifs_file_ops;
 267
 268                 if ((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
 269                    (cifs_sb->tcon->ses->server->maxBuf <
 270                         PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE))
 271                         tmp_inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
 272                 else
 273                         tmp_inode->i_data.a_ops = &cifs_addr_ops;
 274
 275                 if (isNewInode)
 276                         return; /* No sense invalidating pages for new inode
 277                                    since have not started caching readahead file
 278                                    data yet */
 279
 280                 if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
 281                         (local_size == tmp_inode->i_size)) {
 282                         cFYI(1, ("inode exists but unchanged"));
 283                 } else {
 284                         /* file may have changed on server */
 285                         cFYI(1, ("invalidate inode, readdir detected change"));
 286                         invalidate_remote_inode(tmp_inode);
 287                 }
 288         } else if (S_ISDIR(tmp_inode->i_mode)) {
 289                 cFYI(1, ("Directory inode"));
 290                 tmp_inode->i_op = &cifs_dir_inode_ops;
 291                 tmp_inode->i_fop = &cifs_dir_ops;
 292         } else if (S_ISLNK(tmp_inode->i_mode)) {
 293                 cFYI(1, ("Symbolic Link inode"));
 294                 tmp_inode->i_op = &cifs_symlink_inode_ops;
 295         } else {
 296                 cFYI(1, ("Init special inode"));
 297                 init_special_inode(tmp_inode, tmp_inode->i_mode,
 298                                    tmp_inode->i_rdev);
 299         }
 300 }
 301
 302 static void unix_fill_in_inode(struct inode *tmp_inode,
 303         FILE_UNIX_INFO *pfindData, unsigned int *pobject_type, int isNewInode)
 304 {
 305         loff_t local_size;
 306         struct timespec local_mtime;
 307
 308         struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
 309         struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
 310
 311         __u32 type = le32_to_cpu(pfindData->Type);
 312         __u64 num_of_bytes = le64_to_cpu(pfindData->NumOfBytes);
 313         __u64 end_of_file = le64_to_cpu(pfindData->EndOfFile);
 314         cifsInfo->time = jiffies;
 315         atomic_inc(&cifsInfo->inUse);
 316
 317         /* save mtime and size */
 318         local_mtime = tmp_inode->i_mtime;
 319         local_size  = tmp_inode->i_size;
 320
 321         tmp_inode->i_atime =
 322             cifs_NTtimeToUnix(pfindData->LastAccessTime);
 323         tmp_inode->i_mtime =
 324             cifs_NTtimeToUnix(pfindData->LastModificationTime);
 325         tmp_inode->i_ctime =
 326             cifs_NTtimeToUnix(pfindData->LastStatusChange);
 327
 328         tmp_inode->i_mode = le64_to_cpu(pfindData->Permissions);
 329         /* since we set the inode type below we need to mask off type
 330            to avoid strange results if bits above were corrupt */
 331         tmp_inode->i_mode &= ~S_IFMT;
 332         if (type == UNIX_FILE) {
 333                 *pobject_type = DT_REG;
 334                 tmp_inode->i_mode |= S_IFREG;
 335         } else if (type == UNIX_SYMLINK) {
 336                 *pobject_type = DT_LNK;
 337                 tmp_inode->i_mode |= S_IFLNK;
 338         } else if (type == UNIX_DIR) {
 339                 *pobject_type = DT_DIR;
 340                 tmp_inode->i_mode |= S_IFDIR;
 341         } else if (type == UNIX_CHARDEV) {
 342                 *pobject_type = DT_CHR;
 343                 tmp_inode->i_mode |= S_IFCHR;
 344                 tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
 345                                 le64_to_cpu(pfindData->DevMinor) & MINORMASK);
 346         } else if (type == UNIX_BLOCKDEV) {
 347                 *pobject_type = DT_BLK;
 348                 tmp_inode->i_mode |= S_IFBLK;
 349                 tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
 350                                 le64_to_cpu(pfindData->DevMinor) & MINORMASK);
 351         } else if (type == UNIX_FIFO) {
 352                 *pobject_type = DT_FIFO;
 353                 tmp_inode->i_mode |= S_IFIFO;
 354         } else if (type == UNIX_SOCKET) {
 355                 *pobject_type = DT_SOCK;
 356                 tmp_inode->i_mode |= S_IFSOCK;
 357         } else {
 358                 /* safest to just call it a file */
 359                 *pobject_type = DT_REG;
 360                 tmp_inode->i_mode |= S_IFREG;
 361                 cFYI(1, ("unknown inode type %d", type));
 362         }
 363
 364         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)
 365                 tmp_inode->i_uid = cifs_sb->mnt_uid;
 366         else
 367                 tmp_inode->i_uid = le64_to_cpu(pfindData->Uid);
 368         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)
 369                 tmp_inode->i_gid = cifs_sb->mnt_gid;
 370         else
 371                 tmp_inode->i_gid = le64_to_cpu(pfindData->Gid);
 372         tmp_inode->i_nlink = le64_to_cpu(pfindData->Nlinks);
 373
 374         cifsInfo->server_eof = end_of_file;
 375         spin_lock(&tmp_inode->i_lock);
 376         if (is_size_safe_to_change(cifsInfo, end_of_file)) {
 377                 /* can not safely change the file size here if the
 378                 client is writing to it due to potential races */
 379                 i_size_write(tmp_inode, end_of_file);
 380
 381         /* 512 bytes (2**9) is the fake blocksize that must be used */
 382         /* for this calculation, not the real blocksize */
 383                 tmp_inode->i_blocks = (512 - 1 + num_of_bytes) >> 9;
 384         }
 385         spin_unlock(&tmp_inode->i_lock);
 386
 387         if (S_ISREG(tmp_inode->i_mode)) {
 388                 cFYI(1, ("File inode"));
 389                 tmp_inode->i_op = &cifs_file_inode_ops;
 390
 391                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
 392                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 393                                 tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
 394                         else
 395                                 tmp_inode->i_fop = &cifs_file_direct_ops;
 396                 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 397                         tmp_inode->i_fop = &cifs_file_nobrl_ops;
 398                 else
 399                         tmp_inode->i_fop = &cifs_file_ops;
 400
 401                 if ((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
 402                    (cifs_sb->tcon->ses->server->maxBuf <
 403                         PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE))
 404                         tmp_inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
 405                 else
 406                         tmp_inode->i_data.a_ops = &cifs_addr_ops;
 407
 408                 if (isNewInode)
 409                         return; /* No sense invalidating pages for new inode
 410                                    since we have not started caching readahead
 411                                    file data for it yet */
 412
 413                 if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
 414                         (local_size == tmp_inode->i_size)) {
 415                         cFYI(1, ("inode exists but unchanged"));
 416                 } else {
 417                         /* file may have changed on server */
 418                         cFYI(1, ("invalidate inode, readdir detected change"));
 419                         invalidate_remote_inode(tmp_inode);
 420                 }
 421         } else if (S_ISDIR(tmp_inode->i_mode)) {
 422                 cFYI(1, ("Directory inode"));
 423                 tmp_inode->i_op = &cifs_dir_inode_ops;
 424                 tmp_inode->i_fop = &cifs_dir_ops;
 425         } else if (S_ISLNK(tmp_inode->i_mode)) {
 426                 cFYI(1, ("Symbolic Link inode"));
 427                 tmp_inode->i_op = &cifs_symlink_inode_ops;
 428 /* tmp_inode->i_fop = *//* do not need to set to anything */
 429         } else {
 430                 cFYI(1, ("Special inode"));
 431                 init_special_inode(tmp_inode, tmp_inode->i_mode,
 432                                    tmp_inode->i_rdev);
 433         }
 434 }
 435
 436 /* BB eventually need to add the following helper function to
 437       resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
 438       we try to do FindFirst on (NTFS) directory symlinks */
 439 /*
 440 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
 441                              int xid)
 442 {
 443         __u16 fid;
 444         int len;
 445         int oplock = 0;
 446         int rc;
 447         struct cifsTconInfo *ptcon = cifs_sb->tcon;
 448         char *tmpbuffer;
 449
 450         rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
 451                         OPEN_REPARSE_POINT, &fid, &oplock, NULL,
 452                         cifs_sb->local_nls,
 453                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 454         if (!rc) {
 455                 tmpbuffer = kmalloc(maxpath);
 456                 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
 457                                 tmpbuffer,
 458                                 maxpath -1,
 459                                 fid,
 460                                 cifs_sb->local_nls);
 461                 if (CIFSSMBClose(xid, ptcon, fid)) {
 462                         cFYI(1, ("Error closing temporary reparsepoint open)"));
 463                 }
 464         }
 465 }
 466  */
 467
 468 static int initiate_cifs_search(const int xid, struct file *file)
 469 {
 470         int rc = 0;
 471         char *full_path;
 472         struct cifsFileInfo *cifsFile;
 473         struct cifs_sb_info *cifs_sb;
 474         struct cifsTconInfo *pTcon;
 475
 476         if (file->private_data == NULL) {
 477                 file->private_data =
 478                         kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
 479         }
 480
 481         if (file->private_data == NULL)
 482                 return -ENOMEM;
 483         cifsFile = file->private_data;
 484         cifsFile->invalidHandle = true;
 485         cifsFile->srch_inf.endOfSearch = false;
 486
 487         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 488         if (cifs_sb == NULL)
 489                 return -EINVAL;
 490
 491         pTcon = cifs_sb->tcon;
 492         if (pTcon == NULL)
 493                 return -EINVAL;
 494
 495         full_path = build_path_from_dentry(file->f_path.dentry);
 496
 497         if (full_path == NULL)
 498                 return -ENOMEM;
 499
 500         cFYI(1, ("Full path: %s start at: %lld", full_path, file->f_pos));
 501
 502 ffirst_retry:
 503         /* test for Unix extensions */
 504         /* but now check for them on the share/mount not on the SMB session */
 505 /*      if (pTcon->ses->capabilities & CAP_UNIX) { */
 506         if (pTcon->unix_ext)
 507                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
 508         else if ((pTcon->ses->capabilities &
 509                         (CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
 510                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
 511         } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
 512                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
 513         } else /* not srvinos - BB fixme add check for backlevel? */ {
 514                 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
 515         }
 516
 517         rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
 518                 &cifsFile->netfid, &cifsFile->srch_inf,
 519                 cifs_sb->mnt_cifs_flags &
 520                         CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
 521         if (rc == 0)
 522                 cifsFile->invalidHandle = false;
 523         /* BB add following call to handle readdir on new NTFS symlink errors
 524         else if STATUS_STOPPED_ON_SYMLINK
 525                 call get_symlink_reparse_path and retry with new path */
 526         else if ((rc == -EOPNOTSUPP) &&
 527                 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 528                 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
 529                 goto ffirst_retry;
 530         }
 531         kfree(full_path);
 532         return rc;
 533 }
 534
 535 /* return length of unicode string in bytes */
 536 static int cifs_unicode_bytelen(char *str)
 537 {
 538         int len;
 539         __le16 *ustr = (__le16 *)str;
 540
 541         for (len = 0; len <= PATH_MAX; len++) {
 542                 if (ustr[len] == 0)
 543                         return len << 1;
 544         }
 545         cFYI(1, ("Unicode string longer than PATH_MAX found"));
 546         return len << 1;
 547 }
 548
 549 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
 550 {
 551         char *new_entry;
 552         FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
 553
 554         if (level == SMB_FIND_FILE_INFO_STANDARD) {
 555                 FIND_FILE_STANDARD_INFO *pfData;
 556                 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
 557
 558                 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
 559                                 pfData->FileNameLength;
 560         } else
 561                 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
 562         cFYI(1, ("new entry %p old entry %p", new_entry, old_entry));
 563         /* validate that new_entry is not past end of SMB */
 564         if (new_entry >= end_of_smb) {
 565                 cERROR(1,
 566                       ("search entry %p began after end of SMB %p old entry %p",
 567                         new_entry, end_of_smb, old_entry));
 568                 return NULL;
 569         } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
 570                     (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
 571                   || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
 572                    (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb)))  {
 573                 cERROR(1, ("search entry %p extends after end of SMB %p",
 574                         new_entry, end_of_smb));
 575                 return NULL;
 576         } else
 577                 return new_entry;
 578
 579 }
 580
 581 #define UNICODE_DOT cpu_to_le16(0x2e)
 582
 583 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
 584 static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
 585 {
 586         int rc = 0;
 587         char *filename = NULL;
 588         int len = 0;
 589
 590         if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
 591                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 592                 filename = &pFindData->FileName[0];
 593                 if (cfile->srch_inf.unicode) {
 594                         len = cifs_unicode_bytelen(filename);
 595                 } else {
 596                         /* BB should we make this strnlen of PATH_MAX? */
 597                         len = strnlen(filename, 5);
 598                 }
 599         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
 600                 FILE_DIRECTORY_INFO *pFindData =
 601                         (FILE_DIRECTORY_INFO *)current_entry;
 602                 filename = &pFindData->FileName[0];
 603                 len = le32_to_cpu(pFindData->FileNameLength);
 604         } else if (cfile->srch_inf.info_level ==
 605                         SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 606                 FILE_FULL_DIRECTORY_INFO *pFindData =
 607                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 608                 filename = &pFindData->FileName[0];
 609                 len = le32_to_cpu(pFindData->FileNameLength);
 610         } else if (cfile->srch_inf.info_level ==
 611                         SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 612                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 613                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 614                 filename = &pFindData->FileName[0];
 615                 len = le32_to_cpu(pFindData->FileNameLength);
 616         } else if (cfile->srch_inf.info_level ==
 617                         SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 618                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 619                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 620                 filename = &pFindData->FileName[0];
 621                 len = le32_to_cpu(pFindData->FileNameLength);
 622         } else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
 623                 FIND_FILE_STANDARD_INFO *pFindData =
 624                         (FIND_FILE_STANDARD_INFO *)current_entry;
 625                 filename = &pFindData->FileName[0];
 626                 len = pFindData->FileNameLength;
 627         } else {
 628                 cFYI(1, ("Unknown findfirst level %d",
 629                          cfile->srch_inf.info_level));
 630         }
 631
 632         if (filename) {
 633                 if (cfile->srch_inf.unicode) {
 634                         __le16 *ufilename = (__le16 *)filename;
 635                         if (len == 2) {
 636                                 /* check for . */
 637                                 if (ufilename[0] == UNICODE_DOT)
 638                                         rc = 1;
 639                         } else if (len == 4) {
 640                                 /* check for .. */
 641                                 if ((ufilename[0] == UNICODE_DOT)
 642                                    && (ufilename[1] == UNICODE_DOT))
 643                                         rc = 2;
 644                         }
 645                 } else /* ASCII */ {
 646                         if (len == 1) {
 647                                 if (filename[0] == '.')
 648                                         rc = 1;
 649                         } else if (len == 2) {
 650                                 if ((filename[0] == '.') && (filename[1] == '.'))
 651                                         rc = 2;
 652                         }
 653                 }
 654         }
 655
 656         return rc;
 657 }
 658
 659 /* Check if directory that we are searching has changed so we can decide
 660    whether we can use the cached search results from the previous search */
 661 static int is_dir_changed(struct file *file)
 662 {
 663         struct inode *inode = file->f_path.dentry->d_inode;
 664         struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
 665
 666         if (cifsInfo->time == 0)
 667                 return 1; /* directory was changed, perhaps due to unlink */
 668         else
 669                 return 0;
 670
 671 }
 672
 673 static int cifs_save_resume_key(const char *current_entry,
 674         struct cifsFileInfo *cifsFile)
 675 {
 676         int rc = 0;
 677         unsigned int len = 0;
 678         __u16 level;
 679         char *filename;
 680
 681         if ((cifsFile == NULL) || (current_entry == NULL))
 682                 return -EINVAL;
 683
 684         level = cifsFile->srch_inf.info_level;
 685
 686         if (level == SMB_FIND_FILE_UNIX) {
 687                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 688
 689                 filename = &pFindData->FileName[0];
 690                 if (cifsFile->srch_inf.unicode) {
 691                         len = cifs_unicode_bytelen(filename);
 692                 } else {
 693                         /* BB should we make this strnlen of PATH_MAX? */
 694                         len = strnlen(filename, PATH_MAX);
 695                 }
 696                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 697         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 698                 FILE_DIRECTORY_INFO *pFindData =
 699                         (FILE_DIRECTORY_INFO *)current_entry;
 700                 filename = &pFindData->FileName[0];
 701                 len = le32_to_cpu(pFindData->FileNameLength);
 702                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 703         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 704                 FILE_FULL_DIRECTORY_INFO *pFindData =
 705                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 706                 filename = &pFindData->FileName[0];
 707                 len = le32_to_cpu(pFindData->FileNameLength);
 708                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 709         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 710                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 711                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 712                 filename = &pFindData->FileName[0];
 713                 len = le32_to_cpu(pFindData->FileNameLength);
 714                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 715         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 716                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 717                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 718                 filename = &pFindData->FileName[0];
 719                 len = le32_to_cpu(pFindData->FileNameLength);
 720                 cifsFile->srch_inf.resume_key = pFindData->FileIndex;
 721         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 722                 FIND_FILE_STANDARD_INFO *pFindData =
 723                         (FIND_FILE_STANDARD_INFO *)current_entry;
 724                 filename = &pFindData->FileName[0];
 725                 /* one byte length, no name conversion */
 726                 len = (unsigned int)pFindData->FileNameLength;
 727                 cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
 728         } else {
 729                 cFYI(1, ("Unknown findfirst level %d", level));
 730                 return -EINVAL;
 731         }
 732         cifsFile->srch_inf.resume_name_len = len;
 733         cifsFile->srch_inf.presume_name = filename;
 734         return rc;
 735 }
 736
 737 /* find the corresponding entry in the search */
 738 /* Note that the SMB server returns search entries for . and .. which
 739    complicates logic here if we choose to parse for them and we do not
 740    assume that they are located in the findfirst return buffer.*/
 741 /* We start counting in the buffer with entry 2 and increment for every
 742    entry (do not increment for . or .. entry) */
 743 static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
 744         struct file *file, char **ppCurrentEntry, int *num_to_ret)
 745 {
 746         int rc = 0;
 747         int pos_in_buf = 0;
 748         loff_t first_entry_in_buffer;
 749         loff_t index_to_find = file->f_pos;
 750         struct cifsFileInfo *cifsFile = file->private_data;
 751         /* check if index in the buffer */
 752
 753         if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
 754            (num_to_ret == NULL))
 755                 return -ENOENT;
 756
 757         *ppCurrentEntry = NULL;
 758         first_entry_in_buffer =
 759                 cifsFile->srch_inf.index_of_last_entry -
 760                         cifsFile->srch_inf.entries_in_buffer;
 761
 762         /* if first entry in buf is zero then is first buffer
 763         in search response data which means it is likely . and ..
 764         will be in this buffer, although some servers do not return
 765         . and .. for the root of a drive and for those we need
 766         to start two entries earlier */
 767
 768         dump_cifs_file_struct(file, "In fce ");
 769         if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
 770              is_dir_changed(file)) ||
 771            (index_to_find < first_entry_in_buffer)) {
 772                 /* close and restart search */
 773                 cFYI(1, ("search backing up - close and restart search"));
 774                 write_lock(&GlobalSMBSeslock);
 775                 if (!cifsFile->srch_inf.endOfSearch &&
 776                     !cifsFile->invalidHandle) {
 777                         cifsFile->invalidHandle = true;
 778                         write_unlock(&GlobalSMBSeslock);
 779                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
 780                 } else
 781                         write_unlock(&GlobalSMBSeslock);
 782                 if (cifsFile->srch_inf.ntwrk_buf_start) {
 783                         cFYI(1, ("freeing SMB ff cache buf on search rewind"));
 784                         if (cifsFile->srch_inf.smallBuf)
 785                                 cifs_small_buf_release(cifsFile->srch_inf.
 786                                                 ntwrk_buf_start);
 787                         else
 788                                 cifs_buf_release(cifsFile->srch_inf.
 789                                                 ntwrk_buf_start);
 790                         cifsFile->srch_inf.ntwrk_buf_start = NULL;
 791                 }
 792                 rc = initiate_cifs_search(xid, file);
 793                 if (rc) {
 794                         cFYI(1, ("error %d reinitiating a search on rewind",
 795                                  rc));
 796                         return rc;
 797                 }
 798                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 799         }
 800
 801         while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
 802               (rc == 0) && !cifsFile->srch_inf.endOfSearch) {
 803                 cFYI(1, ("calling findnext2"));
 804                 rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
 805                                   &cifsFile->srch_inf);
 806                 cifs_save_resume_key(cifsFile->srch_inf.last_entry, cifsFile);
 807                 if (rc)
 808                         return -ENOENT;
 809         }
 810         if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
 811                 /* we found the buffer that contains the entry */
 812                 /* scan and find it */
 813                 int i;
 814                 char *current_entry;
 815                 char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
 816                         smbCalcSize((struct smb_hdr *)
 817                                 cifsFile->srch_inf.ntwrk_buf_start);
 818
 819                 current_entry = cifsFile->srch_inf.srch_entries_start;
 820                 first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
 821                                         - cifsFile->srch_inf.entries_in_buffer;
 822                 pos_in_buf = index_to_find - first_entry_in_buffer;
 823                 cFYI(1, ("found entry - pos_in_buf %d", pos_in_buf));
 824
 825                 for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
 826                         /* go entry by entry figuring out which is first */
 827                         current_entry = nxt_dir_entry(current_entry, end_of_smb,
 828                                                 cifsFile->srch_inf.info_level);
 829                 }
 830                 if ((current_entry == NULL) && (i < pos_in_buf)) {
 831                         /* BB fixme - check if we should flag this error */
 832                         cERROR(1, ("reached end of buf searching for pos in buf"
 833                           " %d index to find %lld rc %d",
 834                           pos_in_buf, index_to_find, rc));
 835                 }
 836                 rc = 0;
 837                 *ppCurrentEntry = current_entry;
 838         } else {
 839                 cFYI(1, ("index not in buffer - could not findnext into it"));
 840                 return 0;
 841         }
 842
 843         if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
 844                 cFYI(1, ("can not return entries pos_in_buf beyond last"));
 845                 *num_to_ret = 0;
 846         } else
 847                 *num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
 848
 849         return rc;
 850 }
 851
 852 /* inode num, inode type and filename returned */
 853 static int cifs_get_name_from_search_buf(struct qstr *pqst,
 854         char *current_entry, __u16 level, unsigned int unicode,
 855         struct cifs_sb_info *cifs_sb, unsigned int max_len, __u64 *pinum)
 856 {
 857         int rc = 0;
 858         unsigned int len = 0;
 859         char *filename;
 860         struct nls_table *nlt = cifs_sb->local_nls;
 861
 862         *pinum = 0;
 863
 864         if (level == SMB_FIND_FILE_UNIX) {
 865                 FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
 866
 867                 filename = &pFindData->FileName[0];
 868                 if (unicode) {
 869                         len = cifs_unicode_bytelen(filename);
 870                 } else {
 871                         /* BB should we make this strnlen of PATH_MAX? */
 872                         len = strnlen(filename, PATH_MAX);
 873                 }
 874
 875                 *pinum = le64_to_cpu(pFindData->UniqueId);
 876         } else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
 877                 FILE_DIRECTORY_INFO *pFindData =
 878                         (FILE_DIRECTORY_INFO *)current_entry;
 879                 filename = &pFindData->FileName[0];
 880                 len = le32_to_cpu(pFindData->FileNameLength);
 881         } else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
 882                 FILE_FULL_DIRECTORY_INFO *pFindData =
 883                         (FILE_FULL_DIRECTORY_INFO *)current_entry;
 884                 filename = &pFindData->FileName[0];
 885                 len = le32_to_cpu(pFindData->FileNameLength);
 886         } else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
 887                 SEARCH_ID_FULL_DIR_INFO *pFindData =
 888                         (SEARCH_ID_FULL_DIR_INFO *)current_entry;
 889                 filename = &pFindData->FileName[0];
 890                 len = le32_to_cpu(pFindData->FileNameLength);
 891                 *pinum = le64_to_cpu(pFindData->UniqueId);
 892         } else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
 893                 FILE_BOTH_DIRECTORY_INFO *pFindData =
 894                         (FILE_BOTH_DIRECTORY_INFO *)current_entry;
 895                 filename = &pFindData->FileName[0];
 896                 len = le32_to_cpu(pFindData->FileNameLength);
 897         } else if (level == SMB_FIND_FILE_INFO_STANDARD) {
 898                 FIND_FILE_STANDARD_INFO *pFindData =
 899                         (FIND_FILE_STANDARD_INFO *)current_entry;
 900                 filename = &pFindData->FileName[0];
 901                 /* one byte length, no name conversion */
 902                 len = (unsigned int)pFindData->FileNameLength;
 903         } else {
 904                 cFYI(1, ("Unknown findfirst level %d", level));
 905                 return -EINVAL;
 906         }
 907
 908         if (len > max_len) {
 909                 cERROR(1, ("bad search response length %d past smb end", len));
 910                 return -EINVAL;
 911         }
 912
 913         if (unicode) {
 914                 pqst->len = cifs_from_ucs2((char *) pqst->name,
 915                                            (__le16 *) filename,
 916                                            UNICODE_NAME_MAX,
 917                                            min(len, max_len), nlt,
 918                                            cifs_sb->mnt_cifs_flags &
 919                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 920         } else {
 921                 pqst->name = filename;
 922                 pqst->len = len;
 923         }
 924         pqst->hash = full_name_hash(pqst->name, pqst->len);
 925 /*      cFYI(1, ("filldir on %s",pqst->name));  */
 926         return rc;
 927 }
 928
 929 static int cifs_filldir(char *pfindEntry, struct file *file, filldir_t filldir,
 930                         void *direntry, char *scratch_buf, unsigned int max_len)
 931 {
 932         int rc = 0;
 933         struct qstr qstring;
 934         struct cifsFileInfo *pCifsF;
 935         unsigned int obj_type;
 936         __u64  inum;
 937         struct cifs_sb_info *cifs_sb;
 938         struct inode *tmp_inode;
 939         struct dentry *tmp_dentry;
 940
 941         /* get filename and len into qstring */
 942         /* get dentry */
 943         /* decide whether to create and populate ionde */
 944         if ((direntry == NULL) || (file == NULL))
 945                 return -EINVAL;
 946
 947         pCifsF = file->private_data;
 948
 949         if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
 950                 return -ENOENT;
 951
 952         rc = cifs_entry_is_dot(pfindEntry, pCifsF);
 953         /* skip . and .. since we added them first */
 954         if (rc != 0)
 955                 return 0;
 956
 957         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
 958
 959         qstring.name = scratch_buf;
 960         rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
 961                         pCifsF->srch_inf.info_level,
 962                         pCifsF->srch_inf.unicode, cifs_sb,
 963                         max_len,
 964                         &inum /* returned */);
 965
 966         if (rc)
 967                 return rc;
 968
 969         /* only these two infolevels return valid inode numbers */
 970         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX ||
 971             pCifsF->srch_inf.info_level == SMB_FIND_FILE_ID_FULL_DIR_INFO)
 972                 rc = construct_dentry(&qstring, file, &tmp_inode, &tmp_dentry,
 973                                         &inum);
 974         else
 975                 rc = construct_dentry(&qstring, file, &tmp_inode, &tmp_dentry,
 976                                         NULL);
 977
 978         if ((tmp_inode == NULL) || (tmp_dentry == NULL))
 979                 return -ENOMEM;
 980
 981         /* we pass in rc below, indicating whether it is a new inode,
 982            so we can figure out whether to invalidate the inode cached
 983            data if the file has changed */
 984         if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
 985                 unix_fill_in_inode(tmp_inode,
 986                                    (FILE_UNIX_INFO *)pfindEntry,
 987                                    &obj_type, rc);
 988         else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
 989                 fill_in_inode(tmp_inode, 0 /* old level 1 buffer type */,
 990                                 pfindEntry, &obj_type, rc);
 991         else
 992                 fill_in_inode(tmp_inode, 1 /* NT */, pfindEntry, &obj_type, rc);
 993
 994         if (rc) /* new inode - needs to be tied to dentry */ {
 995                 d_instantiate(tmp_dentry, tmp_inode);
 996                 if (rc == 2)
 997                         d_rehash(tmp_dentry);
 998         }
 999
1000
1001         rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
1002                      tmp_inode->i_ino, obj_type);
1003         if (rc) {
1004                 cFYI(1, ("filldir rc = %d", rc));
1005                 /* we can not return filldir errors to the caller
1006                 since they are "normal" when the stat blocksize
1007                 is too small - we return remapped error instead */
1008                 rc = -EOVERFLOW;
1009         }
1010
1011         dput(tmp_dentry);
1012         return rc;
1013 }
1014
1015
1016 int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
1017 {
1018         int rc = 0;
1019         int xid, i;
1020         struct cifs_sb_info *cifs_sb;
1021         struct cifsTconInfo *pTcon;
1022         struct cifsFileInfo *cifsFile = NULL;
1023         char *current_entry;
1024         int num_to_fill = 0;
1025         char *tmp_buf = NULL;
1026         char *end_of_smb;
1027         unsigned int max_len;
1028
1029         xid = GetXid();
1030
1031         cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1032         pTcon = cifs_sb->tcon;
1033         if (pTcon == NULL)
1034                 return -EINVAL;
1035
1036         switch ((int) file->f_pos) {
1037         case 0:
1038                 if (filldir(direntry, ".", 1, file->f_pos,
1039                      file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
1040                         cERROR(1, ("Filldir for current dir failed"));
1041                         rc = -ENOMEM;
1042                         break;
1043                 }
1044                 file->f_pos++;
1045         case 1:
1046                 if (filldir(direntry, "..", 2, file->f_pos,
1047                      file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
1048                         cERROR(1, ("Filldir for parent dir failed"));
1049                         rc = -ENOMEM;
1050                         break;
1051                 }
1052                 file->f_pos++;
1053         default:
1054                 /* 1) If search is active,
1055                         is in current search buffer?
1056                         if it before then restart search
1057                         if after then keep searching till find it */
1058
1059                 if (file->private_data == NULL) {
1060                         rc = initiate_cifs_search(xid, file);
1061                         cFYI(1, ("initiate cifs search rc %d", rc));
1062                         if (rc) {
1063                                 FreeXid(xid);
1064                                 return rc;
1065                         }
1066                 }
1067                 if (file->private_data == NULL) {
1068                         rc = -EINVAL;
1069                         FreeXid(xid);
1070                         return rc;
1071                 }
1072                 cifsFile = file->private_data;
1073                 if (cifsFile->srch_inf.endOfSearch) {
1074                         if (cifsFile->srch_inf.emptyDir) {
1075                                 cFYI(1, ("End of search, empty dir"));
1076                                 rc = 0;
1077                                 break;
1078                         }
1079                 } /* else {
1080                         cifsFile->invalidHandle = true;
1081                         CIFSFindClose(xid, pTcon, cifsFile->netfid);
1082                 } */
1083
1084                 rc = find_cifs_entry(xid, pTcon, file,
1085                                 &current_entry, &num_to_fill);
1086                 if (rc) {
1087                         cFYI(1, ("fce error %d", rc));
1088                         goto rddir2_exit;
1089                 } else if (current_entry != NULL) {
1090                         cFYI(1, ("entry %lld found", file->f_pos));
1091                 } else {
1092                         cFYI(1, ("could not find entry"));
1093                         goto rddir2_exit;
1094                 }
1095                 cFYI(1, ("loop through %d times filling dir for net buf %p",
1096                         num_to_fill, cifsFile->srch_inf.ntwrk_buf_start));
1097                 max_len = smbCalcSize((struct smb_hdr *)
1098                                 cifsFile->srch_inf.ntwrk_buf_start);
1099                 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
1100
1101                 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
1102                 for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
1103                         if (current_entry == NULL) {
1104                                 /* evaluate whether this case is an error */
1105                                 cERROR(1, ("past SMB end,  num to fill %d i %d",
1106                                           num_to_fill, i));
1107                                 break;
1108                         }
1109                         /* if buggy server returns . and .. late do
1110                         we want to check for that here? */
1111                         rc = cifs_filldir(current_entry, file,
1112                                         filldir, direntry, tmp_buf, max_len);
1113                         if (rc == -EOVERFLOW) {
1114                                 rc = 0;
1115                                 break;
1116                         }
1117
1118                         file->f_pos++;
1119                         if (file->f_pos ==
1120                                 cifsFile->srch_inf.index_of_last_entry) {
1121                                 cFYI(1, ("last entry in buf at pos %lld %s",
1122                                         file->f_pos, tmp_buf));
1123                                 cifs_save_resume_key(current_entry, cifsFile);
1124                                 break;
1125                         } else
1126                                 current_entry =
1127                                         nxt_dir_entry(current_entry, end_of_smb,
1128                                                 cifsFile->srch_inf.info_level);
1129                 }
1130                 kfree(tmp_buf);
1131                 break;
1132         } /* end switch */
1133
1134 rddir2_exit:
1135         FreeXid(xid);
1136         return rc;
1137 }