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