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