fs/cifs/file.c

   1 /*
   2  *   fs/cifs/file.c
   3  *
   4  *   vfs operations that deal with files
   5  *
   6  *   Copyright (C) International Business Machines  Corp., 2002,2003
   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/backing-dev.h>
  25 #include <linux/stat.h>
  26 #include <linux/fcntl.h>
  27 #include <linux/mpage.h>
  28 #include <linux/pagemap.h>
  29 #include <linux/pagevec.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/writeback.h>
  32 #include <asm/div64.h>
  33 #include "cifsfs.h"
  34 #include "cifspdu.h"
  35 #include "cifsglob.h"
  36 #include "cifsproto.h"
  37 #include "cifs_unicode.h"
  38 #include "cifs_debug.h"
  39 #include "cifs_fs_sb.h"
  40
  41 static inline struct cifsFileInfo *cifs_init_private(
  42         struct cifsFileInfo *private_data, struct inode *inode,
  43         struct file *file, __u16 netfid)
  44 {
  45         memset(private_data, 0, sizeof(struct cifsFileInfo));
  46         private_data->netfid = netfid;
  47         private_data->pid = current->tgid;
  48         init_MUTEX(&private_data->fh_sem);
  49         private_data->pfile = file; /* needed for writepage */
  50         private_data->pInode = inode;
  51         private_data->invalidHandle = FALSE;
  52         private_data->closePend = FALSE;
  53
  54         return private_data;
  55 }
  56
  57 static inline int cifs_convert_flags(unsigned int flags)
  58 {
  59         if ((flags & O_ACCMODE) == O_RDONLY)
  60                 return GENERIC_READ;
  61         else if ((flags & O_ACCMODE) == O_WRONLY)
  62                 return GENERIC_WRITE;
  63         else if ((flags & O_ACCMODE) == O_RDWR) {
  64                 /* GENERIC_ALL is too much permission to request
  65                    can cause unnecessary access denied on create */
  66                 /* return GENERIC_ALL; */
  67                 return (GENERIC_READ | GENERIC_WRITE);
  68         }
  69
  70         return 0x20197;
  71 }
  72
  73 static inline int cifs_get_disposition(unsigned int flags)
  74 {
  75         if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
  76                 return FILE_CREATE;
  77         else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
  78                 return FILE_OVERWRITE_IF;
  79         else if ((flags & O_CREAT) == O_CREAT)
  80                 return FILE_OPEN_IF;
  81         else
  82                 return FILE_OPEN;
  83 }
  84
  85 /* all arguments to this function must be checked for validity in caller */
  86 static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
  87         struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile,
  88         struct cifsTconInfo *pTcon, int *oplock, FILE_ALL_INFO *buf,
  89         char *full_path, int xid)
  90 {
  91         struct timespec temp;
  92         int rc;
  93
  94         /* want handles we can use to read with first
  95            in the list so we do not have to walk the
  96            list to search for one in prepare_write */
  97         if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
  98                 list_add_tail(&pCifsFile->flist,
  99                               &pCifsInode->openFileList);
 100         } else {
 101                 list_add(&pCifsFile->flist,
 102                          &pCifsInode->openFileList);
 103         }
 104         write_unlock(&GlobalSMBSeslock);
 105         write_unlock(&file->f_owner.lock);
 106         if (pCifsInode->clientCanCacheRead) {
 107                 /* we have the inode open somewhere else
 108                    no need to discard cache data */
 109                 goto client_can_cache;
 110         }
 111
 112         /* BB need same check in cifs_create too? */
 113         /* if not oplocked, invalidate inode pages if mtime or file
 114            size changed */
 115         temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime));
 116         if (timespec_equal(&file->f_dentry->d_inode->i_mtime, &temp) &&
 117                            (file->f_dentry->d_inode->i_size ==
 118                             (loff_t)le64_to_cpu(buf->EndOfFile))) {
 119                 cFYI(1, ("inode unchanged on server"));
 120         } else {
 121                 if (file->f_dentry->d_inode->i_mapping) {
 122                 /* BB no need to lock inode until after invalidate
 123                    since namei code should already have it locked? */
 124                         filemap_fdatawrite(file->f_dentry->d_inode->i_mapping);
 125                         filemap_fdatawait(file->f_dentry->d_inode->i_mapping);
 126                 }
 127                 cFYI(1, ("invalidating remote inode since open detected it "
 128                          "changed"));
 129                 invalidate_remote_inode(file->f_dentry->d_inode);
 130         }
 131
 132 client_can_cache:
 133         if (pTcon->ses->capabilities & CAP_UNIX)
 134                 rc = cifs_get_inode_info_unix(&file->f_dentry->d_inode,
 135                         full_path, inode->i_sb, xid);
 136         else
 137                 rc = cifs_get_inode_info(&file->f_dentry->d_inode,
 138                         full_path, buf, inode->i_sb, xid);
 139
 140         if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) {
 141                 pCifsInode->clientCanCacheAll = TRUE;
 142                 pCifsInode->clientCanCacheRead = TRUE;
 143                 cFYI(1, ("Exclusive Oplock granted on inode %p",
 144                          file->f_dentry->d_inode));
 145         } else if ((*oplock & 0xF) == OPLOCK_READ)
 146                 pCifsInode->clientCanCacheRead = TRUE;
 147
 148         return rc;
 149 }
 150
 151 int cifs_open(struct inode *inode, struct file *file)
 152 {
 153         int rc = -EACCES;
 154         int xid, oplock;
 155         struct cifs_sb_info *cifs_sb;
 156         struct cifsTconInfo *pTcon;
 157         struct cifsFileInfo *pCifsFile;
 158         struct cifsInodeInfo *pCifsInode;
 159         struct list_head *tmp;
 160         char *full_path = NULL;
 161         int desiredAccess;
 162         int disposition;
 163         __u16 netfid;
 164         FILE_ALL_INFO *buf = NULL;
 165
 166         xid = GetXid();
 167
 168         cifs_sb = CIFS_SB(inode->i_sb);
 169         pTcon = cifs_sb->tcon;
 170
 171         if (file->f_flags & O_CREAT) {
 172                 /* search inode for this file and fill in file->private_data */
 173                 pCifsInode = CIFS_I(file->f_dentry->d_inode);
 174                 read_lock(&GlobalSMBSeslock);
 175                 list_for_each(tmp, &pCifsInode->openFileList) {
 176                         pCifsFile = list_entry(tmp, struct cifsFileInfo,
 177                                                flist);
 178                         if ((pCifsFile->pfile == NULL) &&
 179                             (pCifsFile->pid == current->tgid)) {
 180                                 /* mode set in cifs_create */
 181
 182                                 /* needed for writepage */
 183                                 pCifsFile->pfile = file;
 184
 185                                 file->private_data = pCifsFile;
 186                                 break;
 187                         }
 188                 }
 189                 read_unlock(&GlobalSMBSeslock);
 190                 if (file->private_data != NULL) {
 191                         rc = 0;
 192                         FreeXid(xid);
 193                         return rc;
 194                 } else {
 195                         if (file->f_flags & O_EXCL)
 196                                 cERROR(1, ("could not find file instance for "
 197                                            "new file %p ", file));
 198                 }
 199         }
 200
 201         down(&inode->i_sb->s_vfs_rename_sem);
 202         full_path = build_path_from_dentry(file->f_dentry);
 203         up(&inode->i_sb->s_vfs_rename_sem);
 204         if (full_path == NULL) {
 205                 FreeXid(xid);
 206                 return -ENOMEM;
 207         }
 208
 209         cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
 210                  inode, file->f_flags, full_path));
 211         desiredAccess = cifs_convert_flags(file->f_flags);
 212
 213 /*********************************************************************
 214  *  open flag mapping table:
 215  *
 216  *      POSIX Flag            CIFS Disposition
 217  *      ----------            ----------------
 218  *      O_CREAT               FILE_OPEN_IF
 219  *      O_CREAT | O_EXCL      FILE_CREATE
 220  *      O_CREAT | O_TRUNC     FILE_OVERWRITE_IF
 221  *      O_TRUNC               FILE_OVERWRITE
 222  *      none of the above     FILE_OPEN
 223  *
 224  *      Note that there is not a direct match between disposition
 225  *      FILE_SUPERSEDE (ie create whether or not file exists although
 226  *      O_CREAT | O_TRUNC is similar but truncates the existing
 227  *      file rather than creating a new file as FILE_SUPERSEDE does
 228  *      (which uses the attributes / metadata passed in on open call)
 229  *?
 230  *?  O_SYNC is a reasonable match to CIFS writethrough flag
 231  *?  and the read write flags match reasonably.  O_LARGEFILE
 232  *?  is irrelevant because largefile support is always used
 233  *?  by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
 234  *       O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
 235  *********************************************************************/
 236
 237         disposition = cifs_get_disposition(file->f_flags);
 238
 239         if (oplockEnabled)
 240                 oplock = REQ_OPLOCK;
 241         else
 242                 oplock = FALSE;
 243
 244         /* BB pass O_SYNC flag through on file attributes .. BB */
 245
 246         /* Also refresh inode by passing in file_info buf returned by SMBOpen
 247            and calling get_inode_info with returned buf (at least helps
 248            non-Unix server case) */
 249
 250         /* BB we can not do this if this is the second open of a file
 251            and the first handle has writebehind data, we might be
 252            able to simply do a filemap_fdatawrite/filemap_fdatawait first */
 253         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 254         if (!buf) {
 255                 rc = -ENOMEM;
 256                 goto out;
 257         }
 258         rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
 259                          CREATE_NOT_DIR, &netfid, &oplock, buf,
 260                          cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
 261                                  & CIFS_MOUNT_MAP_SPECIAL_CHR);
 262         if (rc == -EIO) {
 263                 /* Old server, try legacy style OpenX */
 264                 rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
 265                         desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
 266                         cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
 267                                 & CIFS_MOUNT_MAP_SPECIAL_CHR);
 268         }
 269         if (rc) {
 270                 cFYI(1, ("cifs_open returned 0x%x ", rc));
 271                 goto out;
 272         }
 273         file->private_data =
 274                 kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
 275         if (file->private_data == NULL) {
 276                 rc = -ENOMEM;
 277                 goto out;
 278         }
 279         pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
 280         write_lock(&file->f_owner.lock);
 281         write_lock(&GlobalSMBSeslock);
 282         list_add(&pCifsFile->tlist, &pTcon->openFileList);
 283
 284         pCifsInode = CIFS_I(file->f_dentry->d_inode);
 285         if (pCifsInode) {
 286                 rc = cifs_open_inode_helper(inode, file, pCifsInode,
 287                                             pCifsFile, pTcon,
 288                                             &oplock, buf, full_path, xid);
 289         } else {
 290                 write_unlock(&GlobalSMBSeslock);
 291                 write_unlock(&file->f_owner.lock);
 292         }
 293
 294         if (oplock & CIFS_CREATE_ACTION) {
 295                 /* time to set mode which we can not set earlier due to
 296                    problems creating new read-only files */
 297                 if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
 298                         CIFSSMBUnixSetPerms(xid, pTcon, full_path,
 299                                             inode->i_mode,
 300                                             (__u64)-1, (__u64)-1, 0 /* dev */,
 301                                             cifs_sb->local_nls,
 302                                             cifs_sb->mnt_cifs_flags &
 303                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 304                 } else {
 305                         /* BB implement via Windows security descriptors eg
 306                            CIFSSMBWinSetPerms(xid, pTcon, full_path, mode,
 307                                               -1, -1, local_nls);
 308                            in the meantime could set r/o dos attribute when
 309                            perms are eg: mode & 0222 == 0 */
 310                 }
 311         }
 312
 313 out:
 314         kfree(buf);
 315         kfree(full_path);
 316         FreeXid(xid);
 317         return rc;
 318 }
 319
 320 /* Try to reaquire byte range locks that were released when session */
 321 /* to server was lost */
 322 static int cifs_relock_file(struct cifsFileInfo *cifsFile)
 323 {
 324         int rc = 0;
 325
 326 /* BB list all locks open on this file and relock */
 327
 328         return rc;
 329 }
 330
 331 static int cifs_reopen_file(struct inode *inode, struct file *file,
 332         int can_flush)
 333 {
 334         int rc = -EACCES;
 335         int xid, oplock;
 336         struct cifs_sb_info *cifs_sb;
 337         struct cifsTconInfo *pTcon;
 338         struct cifsFileInfo *pCifsFile;
 339         struct cifsInodeInfo *pCifsInode;
 340         char *full_path = NULL;
 341         int desiredAccess;
 342         int disposition = FILE_OPEN;
 343         __u16 netfid;
 344
 345         if (inode == NULL)
 346                 return -EBADF;
 347         if (file->private_data) {
 348                 pCifsFile = (struct cifsFileInfo *)file->private_data;
 349         } else
 350                 return -EBADF;
 351
 352         xid = GetXid();
 353         down(&pCifsFile->fh_sem);
 354         if (pCifsFile->invalidHandle == FALSE) {
 355                 up(&pCifsFile->fh_sem);
 356                 FreeXid(xid);
 357                 return 0;
 358         }
 359
 360         if (file->f_dentry == NULL) {
 361                 up(&pCifsFile->fh_sem);
 362                 cFYI(1, ("failed file reopen, no valid name if dentry freed"));
 363                 FreeXid(xid);
 364                 return -EBADF;
 365         }
 366         cifs_sb = CIFS_SB(inode->i_sb);
 367         pTcon = cifs_sb->tcon;
 368 /* can not grab rename sem here because various ops, including
 369    those that already have the rename sem can end up causing writepage
 370    to get called and if the server was down that means we end up here,
 371    and we can never tell if the caller already has the rename_sem */
 372         full_path = build_path_from_dentry(file->f_dentry);
 373         if (full_path == NULL) {
 374                 up(&pCifsFile->fh_sem);
 375                 FreeXid(xid);
 376                 return -ENOMEM;
 377         }
 378
 379         cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
 380                  inode, file->f_flags,full_path));
 381         desiredAccess = cifs_convert_flags(file->f_flags);
 382
 383         if (oplockEnabled)
 384                 oplock = REQ_OPLOCK;
 385         else
 386                 oplock = FALSE;
 387
 388         /* Can not refresh inode by passing in file_info buf to be returned
 389            by SMBOpen and then calling get_inode_info with returned buf
 390            since file might have write behind data that needs to be flushed
 391            and server version of file size can be stale. If we knew for sure
 392            that inode was not dirty locally we could do this */
 393
 394 /*      buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 395         if (buf == 0) {
 396                 up(&pCifsFile->fh_sem);
 397                 kfree(full_path);
 398                 FreeXid(xid);
 399                 return -ENOMEM;
 400         } */
 401         rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
 402                          CREATE_NOT_DIR, &netfid, &oplock, NULL,
 403                          cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
 404                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 405         if (rc) {
 406                 up(&pCifsFile->fh_sem);
 407                 cFYI(1, ("cifs_open returned 0x%x ", rc));
 408                 cFYI(1, ("oplock: %d ", oplock));
 409         } else {
 410                 pCifsFile->netfid = netfid;
 411                 pCifsFile->invalidHandle = FALSE;
 412                 up(&pCifsFile->fh_sem);
 413                 pCifsInode = CIFS_I(inode);
 414                 if (pCifsInode) {
 415                         if (can_flush) {
 416                                 filemap_fdatawrite(inode->i_mapping);
 417                                 filemap_fdatawait(inode->i_mapping);
 418                         /* temporarily disable caching while we
 419                            go to server to get inode info */
 420                                 pCifsInode->clientCanCacheAll = FALSE;
 421                                 pCifsInode->clientCanCacheRead = FALSE;
 422                                 if (pTcon->ses->capabilities & CAP_UNIX)
 423                                         rc = cifs_get_inode_info_unix(&inode,
 424                                                 full_path, inode->i_sb, xid);
 425                                 else
 426                                         rc = cifs_get_inode_info(&inode,
 427                                                 full_path, NULL, inode->i_sb,
 428                                                 xid);
 429                         } /* else we are writing out data to server already
 430                              and could deadlock if we tried to flush data, and
 431                              since we do not know if we have data that would
 432                              invalidate the current end of file on the server
 433                              we can not go to the server to get the new inod
 434                              info */
 435                         if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
 436                                 pCifsInode->clientCanCacheAll = TRUE;
 437                                 pCifsInode->clientCanCacheRead = TRUE;
 438                                 cFYI(1, ("Exclusive Oplock granted on inode %p",
 439                                          file->f_dentry->d_inode));
 440                         } else if ((oplock & 0xF) == OPLOCK_READ) {
 441                                 pCifsInode->clientCanCacheRead = TRUE;
 442                                 pCifsInode->clientCanCacheAll = FALSE;
 443                         } else {
 444                                 pCifsInode->clientCanCacheRead = FALSE;
 445                                 pCifsInode->clientCanCacheAll = FALSE;
 446                         }
 447                         cifs_relock_file(pCifsFile);
 448                 }
 449         }
 450
 451         kfree(full_path);
 452         FreeXid(xid);
 453         return rc;
 454 }
 455
 456 int cifs_close(struct inode *inode, struct file *file)
 457 {
 458         int rc = 0;
 459         int xid;
 460         struct cifs_sb_info *cifs_sb;
 461         struct cifsTconInfo *pTcon;
 462         struct cifsFileInfo *pSMBFile =
 463                 (struct cifsFileInfo *)file->private_data;
 464
 465         xid = GetXid();
 466
 467         cifs_sb = CIFS_SB(inode->i_sb);
 468         pTcon = cifs_sb->tcon;
 469         if (pSMBFile) {
 470                 pSMBFile->closePend = TRUE;
 471                 write_lock(&file->f_owner.lock);
 472                 if (pTcon) {
 473                         /* no sense reconnecting to close a file that is
 474                            already closed */
 475                         if (pTcon->tidStatus != CifsNeedReconnect) {
 476                                 write_unlock(&file->f_owner.lock);
 477                                 rc = CIFSSMBClose(xid, pTcon,
 478                                                   pSMBFile->netfid);
 479                                 write_lock(&file->f_owner.lock);
 480                         }
 481                 }
 482                 write_lock(&GlobalSMBSeslock);
 483                 list_del(&pSMBFile->flist);
 484                 list_del(&pSMBFile->tlist);
 485                 write_unlock(&GlobalSMBSeslock);
 486                 write_unlock(&file->f_owner.lock);
 487                 kfree(pSMBFile->search_resume_name);
 488                 kfree(file->private_data);
 489                 file->private_data = NULL;
 490         } else
 491                 rc = -EBADF;
 492
 493         if (list_empty(&(CIFS_I(inode)->openFileList))) {
 494                 cFYI(1, ("closing last open instance for inode %p", inode));
 495                 /* if the file is not open we do not know if we can cache info
 496                    on this inode, much less write behind and read ahead */
 497                 CIFS_I(inode)->clientCanCacheRead = FALSE;
 498                 CIFS_I(inode)->clientCanCacheAll  = FALSE;
 499         }
 500         if ((rc ==0) && CIFS_I(inode)->write_behind_rc)
 501                 rc = CIFS_I(inode)->write_behind_rc;
 502         FreeXid(xid);
 503         return rc;
 504 }
 505
 506 int cifs_closedir(struct inode *inode, struct file *file)
 507 {
 508         int rc = 0;
 509         int xid;
 510         struct cifsFileInfo *pCFileStruct =
 511             (struct cifsFileInfo *)file->private_data;
 512         char *ptmp;
 513
 514         cFYI(1, ("Closedir inode = 0x%p with ", inode));
 515
 516         xid = GetXid();
 517
 518         if (pCFileStruct) {
 519                 struct cifsTconInfo *pTcon;
 520                 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_dentry->d_sb);
 521
 522                 pTcon = cifs_sb->tcon;
 523
 524                 cFYI(1, ("Freeing private data in close dir"));
 525                 if ((pCFileStruct->srch_inf.endOfSearch == FALSE) &&
 526                    (pCFileStruct->invalidHandle == FALSE)) {
 527                         pCFileStruct->invalidHandle = TRUE;
 528                         rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
 529                         cFYI(1, ("Closing uncompleted readdir with rc %d",
 530                                  rc));
 531                         /* not much we can do if it fails anyway, ignore rc */
 532                         rc = 0;
 533                 }
 534                 ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
 535                 if (ptmp) {
 536    /* BB removeme BB */ cFYI(1, ("freeing smb buf in srch struct in closedir"));
 537                         pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
 538                         cifs_buf_release(ptmp);
 539                 }
 540                 ptmp = pCFileStruct->search_resume_name;
 541                 if (ptmp) {
 542    /* BB removeme BB */ cFYI(1, ("freeing resume name in closedir"));
 543                         pCFileStruct->search_resume_name = NULL;
 544                         kfree(ptmp);
 545                 }
 546                 kfree(file->private_data);
 547                 file->private_data = NULL;
 548         }
 549         /* BB can we lock the filestruct while this is going on? */
 550         FreeXid(xid);
 551         return rc;
 552 }
 553
 554 int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
 555 {
 556         int rc, xid;
 557         __u32 lockType = LOCKING_ANDX_LARGE_FILES;
 558         __u32 numLock = 0;
 559         __u32 numUnlock = 0;
 560         __u64 length;
 561         int wait_flag = FALSE;
 562         struct cifs_sb_info *cifs_sb;
 563         struct cifsTconInfo *pTcon;
 564
 565         length = 1 + pfLock->fl_end - pfLock->fl_start;
 566         rc = -EACCES;
 567         xid = GetXid();
 568
 569         cFYI(1, ("Lock parm: 0x%x flockflags: "
 570                  "0x%x flocktype: 0x%x start: %lld end: %lld",
 571                 cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
 572                 pfLock->fl_end));
 573
 574         if (pfLock->fl_flags & FL_POSIX)
 575                 cFYI(1, ("Posix "));
 576         if (pfLock->fl_flags & FL_FLOCK)
 577                 cFYI(1, ("Flock "));
 578         if (pfLock->fl_flags & FL_SLEEP) {
 579                 cFYI(1, ("Blocking lock "));
 580                 wait_flag = TRUE;
 581         }
 582         if (pfLock->fl_flags & FL_ACCESS)
 583                 cFYI(1, ("Process suspended by mandatory locking - "
 584                          "not implemented yet "));
 585         if (pfLock->fl_flags & FL_LEASE)
 586                 cFYI(1, ("Lease on file - not implemented yet"));
 587         if (pfLock->fl_flags &
 588             (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
 589                 cFYI(1, ("Unknown lock flags 0x%x", pfLock->fl_flags));
 590
 591         if (pfLock->fl_type == F_WRLCK) {
 592                 cFYI(1, ("F_WRLCK "));
 593                 numLock = 1;
 594         } else if (pfLock->fl_type == F_UNLCK) {
 595                 cFYI(1, ("F_UNLCK "));
 596                 numUnlock = 1;
 597         } else if (pfLock->fl_type == F_RDLCK) {
 598                 cFYI(1, ("F_RDLCK "));
 599                 lockType |= LOCKING_ANDX_SHARED_LOCK;
 600                 numLock = 1;
 601         } else if (pfLock->fl_type == F_EXLCK) {
 602                 cFYI(1, ("F_EXLCK "));
 603                 numLock = 1;
 604         } else if (pfLock->fl_type == F_SHLCK) {
 605                 cFYI(1, ("F_SHLCK "));
 606                 lockType |= LOCKING_ANDX_SHARED_LOCK;
 607                 numLock = 1;
 608         } else
 609                 cFYI(1, ("Unknown type of lock "));
 610
 611         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
 612         pTcon = cifs_sb->tcon;
 613
 614         if (file->private_data == NULL) {
 615                 FreeXid(xid);
 616                 return -EBADF;
 617         }
 618
 619         if (IS_GETLK(cmd)) {
 620                 rc = CIFSSMBLock(xid, pTcon,
 621                                  ((struct cifsFileInfo *)file->
 622                                   private_data)->netfid,
 623                                  length,
 624                                  pfLock->fl_start, 0, 1, lockType,
 625                                  0 /* wait flag */ );
 626                 if (rc == 0) {
 627                         rc = CIFSSMBLock(xid, pTcon,
 628                                          ((struct cifsFileInfo *) file->
 629                                           private_data)->netfid,
 630                                          length,
 631                                          pfLock->fl_start, 1 /* numUnlock */ ,
 632                                          0 /* numLock */ , lockType,
 633                                          0 /* wait flag */ );
 634                         pfLock->fl_type = F_UNLCK;
 635                         if (rc != 0)
 636                                 cERROR(1, ("Error unlocking previously locked "
 637                                            "range %d during test of lock ",
 638                                            rc));
 639                         rc = 0;
 640
 641                 } else {
 642                         /* if rc == ERR_SHARING_VIOLATION ? */
 643                         rc = 0; /* do not change lock type to unlock
 644                                    since range in use */
 645                 }
 646
 647                 FreeXid(xid);
 648                 return rc;
 649         }
 650
 651         rc = CIFSSMBLock(xid, pTcon,
 652                          ((struct cifsFileInfo *) file->private_data)->
 653                          netfid, length,
 654                          pfLock->fl_start, numUnlock, numLock, lockType,
 655                          wait_flag);
 656         if (pfLock->fl_flags & FL_POSIX)
 657                 posix_lock_file_wait(file, pfLock);
 658         FreeXid(xid);
 659         return rc;
 660 }
 661
 662 ssize_t cifs_user_write(struct file *file, const char __user *write_data,
 663         size_t write_size, loff_t *poffset)
 664 {
 665         int rc = 0;
 666         unsigned int bytes_written = 0;
 667         unsigned int total_written;
 668         struct cifs_sb_info *cifs_sb;
 669         struct cifsTconInfo *pTcon;
 670         int xid, long_op;
 671         struct cifsFileInfo *open_file;
 672
 673         if (file->f_dentry == NULL)
 674                 return -EBADF;
 675
 676         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
 677         if (cifs_sb == NULL)
 678                 return -EBADF;
 679
 680         pTcon = cifs_sb->tcon;
 681
 682         /* cFYI(1,
 683            (" write %d bytes to offset %lld of %s", write_size,
 684            *poffset, file->f_dentry->d_name.name)); */
 685
 686         if (file->private_data == NULL)
 687                 return -EBADF;
 688         else
 689                 open_file = (struct cifsFileInfo *) file->private_data;
 690
 691         xid = GetXid();
 692         if (file->f_dentry->d_inode == NULL) {
 693                 FreeXid(xid);
 694                 return -EBADF;
 695         }
 696
 697         if (*poffset > file->f_dentry->d_inode->i_size)
 698                 long_op = 2; /* writes past end of file can take a long time */
 699         else
 700                 long_op = 1;
 701
 702         for (total_written = 0; write_size > total_written;
 703              total_written += bytes_written) {
 704                 rc = -EAGAIN;
 705                 while (rc == -EAGAIN) {
 706                         if (file->private_data == NULL) {
 707                                 /* file has been closed on us */
 708                                 FreeXid(xid);
 709                         /* if we have gotten here we have written some data
 710                            and blocked, and the file has been freed on us while
 711                            we blocked so return what we managed to write */
 712                                 return total_written;
 713                         }
 714                         if (open_file->closePend) {
 715                                 FreeXid(xid);
 716                                 if (total_written)
 717                                         return total_written;
 718                                 else
 719                                         return -EBADF;
 720                         }
 721                         if (open_file->invalidHandle) {
 722                                 if ((file->f_dentry == NULL) ||
 723                                     (file->f_dentry->d_inode == NULL)) {
 724                                         FreeXid(xid);
 725                                         return total_written;
 726                                 }
 727                                 /* we could deadlock if we called
 728                                    filemap_fdatawait from here so tell
 729                                    reopen_file not to flush data to server
 730                                    now */
 731                                 rc = cifs_reopen_file(file->f_dentry->d_inode,
 732                                         file, FALSE);
 733                                 if (rc != 0)
 734                                         break;
 735                         }
 736
 737                         rc = CIFSSMBWrite(xid, pTcon,
 738                                 open_file->netfid,
 739                                 min_t(const int, cifs_sb->wsize,
 740                                       write_size - total_written),
 741                                 *poffset, &bytes_written,
 742                                 NULL, write_data + total_written, long_op);
 743                 }
 744                 if (rc || (bytes_written == 0)) {
 745                         if (total_written)
 746                                 break;
 747                         else {
 748                                 FreeXid(xid);
 749                                 return rc;
 750                         }
 751                 } else
 752                         *poffset += bytes_written;
 753                 long_op = FALSE; /* subsequent writes fast -
 754                                     15 seconds is plenty */
 755         }
 756
 757         cifs_stats_bytes_written(pTcon, total_written);
 758
 759         /* since the write may have blocked check these pointers again */
 760         if (file->f_dentry) {
 761                 if (file->f_dentry->d_inode) {
 762                         struct inode *inode = file->f_dentry->d_inode;
 763                         inode->i_ctime = inode->i_mtime =
 764                                 current_fs_time(inode->i_sb);
 765                         if (total_written > 0) {
 766                                 if (*poffset > file->f_dentry->d_inode->i_size)
 767                                         i_size_write(file->f_dentry->d_inode,
 768                                         *poffset);
 769                         }
 770                         mark_inode_dirty_sync(file->f_dentry->d_inode);
 771                 }
 772         }
 773         FreeXid(xid);
 774         return total_written;
 775 }
 776
 777 static ssize_t cifs_write(struct file *file, const char *write_data,
 778         size_t write_size, loff_t *poffset)
 779 {
 780         int rc = 0;
 781         unsigned int bytes_written = 0;
 782         unsigned int total_written;
 783         struct cifs_sb_info *cifs_sb;
 784         struct cifsTconInfo *pTcon;
 785         int xid, long_op;
 786         struct cifsFileInfo *open_file;
 787
 788         if (file->f_dentry == NULL)
 789                 return -EBADF;
 790
 791         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
 792         if (cifs_sb == NULL)
 793                 return -EBADF;
 794
 795         pTcon = cifs_sb->tcon;
 796
 797         cFYI(1,("write %zd bytes to offset %lld of %s", write_size,
 798            *poffset, file->f_dentry->d_name.name));
 799
 800         if (file->private_data == NULL)
 801                 return -EBADF;
 802         else
 803                 open_file = (struct cifsFileInfo *)file->private_data;
 804
 805         xid = GetXid();
 806         if (file->f_dentry->d_inode == NULL) {
 807                 FreeXid(xid);
 808                 return -EBADF;
 809         }
 810
 811         if (*poffset > file->f_dentry->d_inode->i_size)
 812                 long_op = 2; /* writes past end of file can take a long time */
 813         else
 814                 long_op = 1;
 815
 816         for (total_written = 0; write_size > total_written;
 817              total_written += bytes_written) {
 818                 rc = -EAGAIN;
 819                 while (rc == -EAGAIN) {
 820                         if (file->private_data == NULL) {
 821                                 /* file has been closed on us */
 822                                 FreeXid(xid);
 823                         /* if we have gotten here we have written some data
 824                            and blocked, and the file has been freed on us
 825                            while we blocked so return what we managed to
 826                            write */
 827                                 return total_written;
 828                         }
 829                         if (open_file->closePend) {
 830                                 FreeXid(xid);
 831                                 if (total_written)
 832                                         return total_written;
 833                                 else
 834                                         return -EBADF;
 835                         }
 836                         if (open_file->invalidHandle) {
 837                                 if ((file->f_dentry == NULL) ||
 838                                    (file->f_dentry->d_inode == NULL)) {
 839                                         FreeXid(xid);
 840                                         return total_written;
 841                                 }
 842                                 /* we could deadlock if we called
 843                                    filemap_fdatawait from here so tell
 844                                    reopen_file not to flush data to
 845                                    server now */
 846                                 rc = cifs_reopen_file(file->f_dentry->d_inode,
 847                                         file, FALSE);
 848                                 if (rc != 0)
 849                                         break;
 850                         }
 851 #ifdef CONFIG_CIFS_EXPERIMENTAL
 852                         /* BB FIXME We can not sign across two buffers yet */
 853                         if((experimEnabled) && ((pTcon->ses->server->secMode &
 854                          (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) == 0)) {
 855                                 struct kvec iov[2];
 856                                 unsigned int len;
 857
 858                                 len = min(cifs_sb->wsize,
 859                                           write_size - total_written);
 860                                 /* iov[0] is reserved for smb header */
 861                                 iov[1].iov_base = (char *)write_data +
 862                                                   total_written;
 863                                 iov[1].iov_len = len;
 864                                 rc = CIFSSMBWrite2(xid, pTcon,
 865                                                 open_file->netfid, len,
 866                                                 *poffset, &bytes_written,
 867                                                 iov, 1, long_op);
 868                         } else
 869                         /* BB FIXME fixup indentation of line below */
 870 #endif
 871                         rc = CIFSSMBWrite(xid, pTcon,
 872                                  open_file->netfid,
 873                                  min_t(const int, cifs_sb->wsize,
 874                                        write_size - total_written),
 875                                  *poffset, &bytes_written,
 876                                  write_data + total_written, NULL, long_op);
 877                 }
 878                 if (rc || (bytes_written == 0)) {
 879                         if (total_written)
 880                                 break;
 881                         else {
 882                                 FreeXid(xid);
 883                                 return rc;
 884                         }
 885                 } else
 886                         *poffset += bytes_written;
 887                 long_op = FALSE; /* subsequent writes fast -
 888                                     15 seconds is plenty */
 889         }
 890
 891         cifs_stats_bytes_written(pTcon, total_written);
 892
 893         /* since the write may have blocked check these pointers again */
 894         if (file->f_dentry) {
 895                 if (file->f_dentry->d_inode) {
 896                         file->f_dentry->d_inode->i_ctime =
 897                         file->f_dentry->d_inode->i_mtime = CURRENT_TIME;
 898                         if (total_written > 0) {
 899                                 if (*poffset > file->f_dentry->d_inode->i_size)
 900                                         i_size_write(file->f_dentry->d_inode,
 901                                                      *poffset);
 902                         }
 903                         mark_inode_dirty_sync(file->f_dentry->d_inode);
 904                 }
 905         }
 906         FreeXid(xid);
 907         return total_written;
 908 }
 909
 910 static struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
 911 {
 912         struct cifsFileInfo *open_file;
 913
 914         read_lock(&GlobalSMBSeslock);
 915         list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
 916                 if (open_file->closePend)
 917                         continue;
 918                 if (open_file->pfile &&
 919                     ((open_file->pfile->f_flags & O_RDWR) ||
 920                      (open_file->pfile->f_flags & O_WRONLY))) {
 921                         read_unlock(&GlobalSMBSeslock);
 922                         if(open_file->invalidHandle) {
 923                                 rc = cifs_reopen_file(cifs_inode->vfs_inode,
 924                                                       open_file->pfile, FALSE);
 925                                 /* if it fails, try another handle - might be */
 926                                 /* dangerous to hold up writepages with retry */
 927                                 if(rc) {
 928                                         read_lock(&GlobalSMBSeslock);
 929                                         continue;
 930                                 }
 931                         }
 932                         return open_file;
 933                 }
 934         }
 935         read_unlock(&GlobalSMBSeslock);
 936         return NULL;
 937 }
 938
 939 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
 940 {
 941         struct address_space *mapping = page->mapping;
 942         loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
 943         char *write_data;
 944         int rc = -EFAULT;
 945         int bytes_written = 0;
 946         struct cifs_sb_info *cifs_sb;
 947         struct cifsTconInfo *pTcon;
 948         struct inode *inode;
 949         struct cifsFileInfo *open_file;
 950
 951         if (!mapping || !mapping->host)
 952                 return -EFAULT;
 953
 954         inode = page->mapping->host;
 955         cifs_sb = CIFS_SB(inode->i_sb);
 956         pTcon = cifs_sb->tcon;
 957
 958         offset += (loff_t)from;
 959         write_data = kmap(page);
 960         write_data += from;
 961
 962         if ((to > PAGE_CACHE_SIZE) || (from > to)) {
 963                 kunmap(page);
 964                 return -EIO;
 965         }
 966
 967         /* racing with truncate? */
 968         if (offset > mapping->host->i_size) {
 969                 kunmap(page);
 970                 return 0; /* don't care */
 971         }
 972
 973         /* check to make sure that we are not extending the file */
 974         if (mapping->host->i_size - offset < (loff_t)to)
 975                 to = (unsigned)(mapping->host->i_size - offset);
 976
 977         open_file = find_writable_file(CIFS_I(mapping->host));
 978         if (open_file) {
 979                 bytes_written = cifs_write(open_file->pfile, write_data,
 980                                            to-from, &offset);
 981                 /* Does mm or vfs already set times? */
 982                 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
 983                 if ((bytes_written > 0) && (offset)) {
 984                         rc = 0;
 985                 } else if (bytes_written < 0) {
 986                         if (rc != -EBADF)
 987                                 rc = bytes_written;
 988                 }
 989         } else {
 990                 cFYI(1, ("No writeable filehandles for inode"));
 991                 rc = -EIO;
 992         }
 993
 994         kunmap(page);
 995         return rc;
 996 }
 997
 998 #ifdef CONFIG_CIFS_EXPERIMENTAL
 999 static int cifs_writepages(struct address_space *mapping,
1000                            struct writeback_control *wbc)
1001 {
1002         struct backing_dev_info *bdi = mapping->backing_dev_info;
1003         unsigned int bytes_to_write;
1004         unsigned int bytes_written;
1005         struct cifs_sb_info *cifs_sb;
1006         int done = 0;
1007         pgoff_t end = -1;
1008         pgoff_t index;
1009         int is_range = 0;
1010         struct kvec iov[32];
1011         int n_iov = 0;
1012         pgoff_t next;
1013         int nr_pages;
1014         __u64 offset = 0;
1015         struct cifsFileInfo *open_file = NULL;
1016         struct page *page;
1017         struct pagevec pvec;
1018         int rc = 0;
1019         int scanned = 0;
1020         int xid;
1021
1022         cifs_sb = CIFS_SB(mapping->host->i_sb);
1023
1024         /*
1025          * If wsize is smaller that the page cache size, default to writing
1026          * one page at a time via cifs_writepage
1027          */
1028         if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1029                 return generic_writepages(mapping, wbc);
1030
1031         /*
1032          * BB: Is this meaningful for a non-block-device file system?
1033          * If it is, we should test it again after we do I/O
1034          */
1035         if (wbc->nonblocking && bdi_write_congested(bdi)) {
1036                 wbc->encountered_congestion = 1;
1037                 return 0;
1038         }
1039
1040         xid = GetXid();
1041
1042         pagevec_init(&pvec, 0);
1043         if (wbc->sync_mode == WB_SYNC_NONE)
1044                 index = mapping->writeback_index; /* Start from prev offset */
1045         else {
1046                 index = 0;
1047                 scanned = 1;
1048         }
1049         if (wbc->start || wbc->end) {
1050                 index = wbc->start >> PAGE_CACHE_SHIFT;
1051                 end = wbc->end >> PAGE_CACHE_SHIFT;
1052                 is_range = 1;
1053                 scanned = 1;
1054         }
1055 retry:
1056         while (!done && (index <= end) &&
1057                (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
1058                         PAGECACHE_TAG_DIRTY,
1059                         min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
1060                 int first;
1061                 unsigned int i;
1062
1063                 if (!open_file) {
1064                         open_file = find_writable_file(CIFS_I(mapping->host));
1065                         if (!open_file) {
1066                                 pagevec_release(&pvec);
1067                                 cERROR(1, ("No writable handles for inode"));
1068                                 return -EIO;
1069                         }
1070                 }
1071
1072                 first = -1;
1073                 next = 0;
1074                 n_iov = 0;
1075                 bytes_to_write = 0;
1076
1077                 for (i = 0; i < nr_pages; i++) {
1078                         page = pvec.pages[i];
1079                         /*
1080                          * At this point we hold neither mapping->tree_lock nor
1081                          * lock on the page itself: the page may be truncated or
1082                          * invalidated (changing page->mapping to NULL), or even
1083                          * swizzled back from swapper_space to tmpfs file
1084                          * mapping
1085                          */
1086
1087                         if (first < 0)
1088                                 lock_page(page);
1089                         else if (TestSetPageLocked(page))
1090                                 break;
1091
1092                         if (unlikely(page->mapping != mapping)) {
1093                                 unlock_page(page);
1094                                 break;
1095                         }
1096
1097                         if (unlikely(is_range) && (page->index > end)) {
1098                                 done = 1;
1099                                 unlock_page(page);
1100                                 break;
1101                         }
1102
1103                         if (next && (page->index != next)) {
1104                                 /* Not next consecutive page */
1105                                 unlock_page(page);
1106                                 break;
1107                         }
1108
1109                         if (wbc->sync_mode != WB_SYNC_NONE)
1110                                 wait_on_page_writeback(page);
1111
1112                         if (PageWriteback(page) ||
1113                                         !test_clear_page_dirty(page)) {
1114                                 unlock_page(page);
1115                                 break;
1116                         }
1117                         /*
1118                          * BB can we get rid of this?  pages are held by pvec
1119                          */
1120                         page_cache_get(page);
1121
1122                         /* reserve iov[0] for the smb header */
1123                         n_iov++;
1124                         iov[n_iov].iov_base = kmap(page);
1125                         iov[n_iov].iov_len = PAGE_CACHE_SIZE;
1126                         bytes_to_write += PAGE_CACHE_SIZE;
1127
1128                         if (first < 0) {
1129                                 first = i;
1130                                 offset = page_offset(page);
1131                         }
1132                         next = page->index + 1;
1133                         if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
1134                                 break;
1135                 }
1136                 if (n_iov) {
1137                         rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
1138                                            open_file->netfid, bytes_to_write,
1139                                            offset, &bytes_written, iov, n_iov,
1140                                            1);
1141                         if (rc || bytes_written < bytes_to_write) {
1142                                 cERROR(1,("CIFSSMBWrite2 returned %d, written = %x",
1143                                           rc, bytes_written));
1144                                 set_bit(AS_EIO, &mapping->flags);
1145                                 SetPageError(page);
1146                         }
1147                         for (i = 0; i < n_iov; i++) {
1148                                 page = pvec.pages[first + i];
1149                                 kunmap(page);
1150                                 unlock_page(page);
1151                                 page_cache_release(page);
1152                         }
1153                         if ((wbc->nr_to_write -= n_iov) <= 0)
1154                                 done = 1;
1155                         index = next;
1156                 }
1157                 pagevec_release(&pvec);
1158         }
1159         if (!scanned && !done) {
1160                 /*
1161                  * We hit the last page and there is more work to be done: wrap
1162                  * back to the start of the file
1163                  */
1164                 scanned = 1;
1165                 index = 0;
1166                 goto retry;
1167         }
1168         if (!is_range)
1169                 mapping->writeback_index = index;
1170
1171         FreeXid(xid);
1172
1173         return rc;
1174 }
1175 #endif
1176
1177 static int cifs_writepage(struct page* page, struct writeback_control *wbc)
1178 {
1179         int rc = -EFAULT;
1180         int xid;
1181
1182         xid = GetXid();
1183 /* BB add check for wbc flags */
1184         page_cache_get(page);
1185         if (!PageUptodate(page)) {
1186                 cFYI(1, ("ppw - page not up to date"));
1187         }
1188
1189         rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1190         SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
1191         unlock_page(page);
1192         page_cache_release(page);
1193         FreeXid(xid);
1194         return rc;
1195 }
1196
1197 static int cifs_commit_write(struct file *file, struct page *page,
1198         unsigned offset, unsigned to)
1199 {
1200         int xid;
1201         int rc = 0;
1202         struct inode *inode = page->mapping->host;
1203         loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
1204         char *page_data;
1205
1206         xid = GetXid();
1207         cFYI(1, ("commit write for page %p up to position %lld for %d",
1208                  page, position, to));
1209         if (position > inode->i_size) {
1210                 i_size_write(inode, position);
1211                 /* if (file->private_data == NULL) {
1212                         rc = -EBADF;
1213                 } else {
1214                         open_file = (struct cifsFileInfo *)file->private_data;
1215                         cifs_sb = CIFS_SB(inode->i_sb);
1216                         rc = -EAGAIN;
1217                         while (rc == -EAGAIN) {
1218                                 if ((open_file->invalidHandle) &&
1219                                     (!open_file->closePend)) {
1220                                         rc = cifs_reopen_file(
1221                                                 file->f_dentry->d_inode, file);
1222                                         if (rc != 0)
1223                                                 break;
1224                                 }
1225                                 if (!open_file->closePend) {
1226                                         rc = CIFSSMBSetFileSize(xid,
1227                                                 cifs_sb->tcon, position,
1228                                                 open_file->netfid,
1229                                                 open_file->pid, FALSE);
1230                                 } else {
1231                                         rc = -EBADF;
1232                                         break;
1233                                 }
1234                         }
1235                         cFYI(1, (" SetEOF (commit write) rc = %d", rc));
1236                 } */
1237         }
1238         if (!PageUptodate(page)) {
1239                 position =  ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset;
1240                 /* can not rely on (or let) writepage write this data */
1241                 if (to < offset) {
1242                         cFYI(1, ("Illegal offsets, can not copy from %d to %d",
1243                                 offset, to));
1244                         FreeXid(xid);
1245                         return rc;
1246                 }
1247                 /* this is probably better than directly calling
1248                    partialpage_write since in this function the file handle is
1249                    known which we might as well leverage */
1250                 /* BB check if anything else missing out of ppw
1251                    such as updating last write time */
1252                 page_data = kmap(page);
1253                 rc = cifs_write(file, page_data + offset, to-offset,
1254                                 &position);
1255                 if (rc > 0)
1256                         rc = 0;
1257                 /* else if (rc < 0) should we set writebehind rc? */
1258                 kunmap(page);
1259         } else {
1260                 set_page_dirty(page);
1261         }
1262
1263         FreeXid(xid);
1264         return rc;
1265 }
1266
1267 int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
1268 {
1269         int xid;
1270         int rc = 0;
1271         struct inode *inode = file->f_dentry->d_inode;
1272
1273         xid = GetXid();
1274
1275         cFYI(1, ("Sync file - name: %s datasync: 0x%x ",
1276                 dentry->d_name.name, datasync));
1277
1278         rc = filemap_fdatawrite(inode->i_mapping);
1279         if (rc == 0)
1280                 CIFS_I(inode)->write_behind_rc = 0;
1281         FreeXid(xid);
1282         return rc;
1283 }
1284
1285 /* static int cifs_sync_page(struct page *page)
1286 {
1287         struct address_space *mapping;
1288         struct inode *inode;
1289         unsigned long index = page->index;
1290         unsigned int rpages = 0;
1291         int rc = 0;
1292
1293         cFYI(1, ("sync page %p",page));
1294         mapping = page->mapping;
1295         if (!mapping)
1296                 return 0;
1297         inode = mapping->host;
1298         if (!inode)
1299                 return 0; */
1300
1301 /*      fill in rpages then
1302         result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
1303
1304 /*      cFYI(1, ("rpages is %d for sync page of Index %ld ", rpages, index));
1305
1306         if (rc < 0)
1307                 return rc;
1308         return 0;
1309 } */
1310
1311 /*
1312  * As file closes, flush all cached write data for this inode checking
1313  * for write behind errors.
1314  */
1315 int cifs_flush(struct file *file)
1316 {
1317         struct inode * inode = file->f_dentry->d_inode;
1318         int rc = 0;
1319
1320         /* Rather than do the steps manually:
1321            lock the inode for writing
1322            loop through pages looking for write behind data (dirty pages)
1323            coalesce into contiguous 16K (or smaller) chunks to write to server
1324            send to server (prefer in parallel)
1325            deal with writebehind errors
1326            unlock inode for writing
1327            filemapfdatawrite appears easier for the time being */
1328
1329         rc = filemap_fdatawrite(inode->i_mapping);
1330         if (!rc) /* reset wb rc if we were able to write out dirty pages */
1331                 CIFS_I(inode)->write_behind_rc = 0;
1332
1333         cFYI(1, ("Flush inode %p file %p rc %d",inode,file,rc));
1334
1335         return rc;
1336 }
1337
1338 ssize_t cifs_user_read(struct file *file, char __user *read_data,
1339         size_t read_size, loff_t *poffset)
1340 {
1341         int rc = -EACCES;
1342         unsigned int bytes_read = 0;
1343         unsigned int total_read = 0;
1344         unsigned int current_read_size;
1345         struct cifs_sb_info *cifs_sb;
1346         struct cifsTconInfo *pTcon;
1347         int xid;
1348         struct cifsFileInfo *open_file;
1349         char *smb_read_data;
1350         char __user *current_offset;
1351         struct smb_com_read_rsp *pSMBr;
1352
1353         xid = GetXid();
1354         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1355         pTcon = cifs_sb->tcon;
1356
1357         if (file->private_data == NULL) {
1358                 FreeXid(xid);
1359                 return -EBADF;
1360         }
1361         open_file = (struct cifsFileInfo *)file->private_data;
1362
1363         if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
1364                 cFYI(1, ("attempting read on write only file instance"));
1365         }
1366         for (total_read = 0, current_offset = read_data;
1367              read_size > total_read;
1368              total_read += bytes_read, current_offset += bytes_read) {
1369                 current_read_size = min_t(const int, read_size - total_read,
1370                                           cifs_sb->rsize);
1371                 rc = -EAGAIN;
1372                 smb_read_data = NULL;
1373                 while (rc == -EAGAIN) {
1374                         if ((open_file->invalidHandle) &&
1375                             (!open_file->closePend)) {
1376                                 rc = cifs_reopen_file(file->f_dentry->d_inode,
1377                                         file, TRUE);
1378                                 if (rc != 0)
1379                                         break;
1380                         }
1381                         rc = CIFSSMBRead(xid, pTcon,
1382                                         open_file->netfid,
1383                                         current_read_size, *poffset,
1384                                         &bytes_read, &smb_read_data);
1385                         pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1386                         if (copy_to_user(current_offset,
1387                                          smb_read_data + 4 /* RFC1001 hdr */
1388                                          + le16_to_cpu(pSMBr->DataOffset),
1389                                          bytes_read)) {
1390                                 rc = -EFAULT;
1391                                 FreeXid(xid);
1392                                 return rc;
1393             }
1394                         if (smb_read_data) {
1395                                 cifs_buf_release(smb_read_data);
1396                                 smb_read_data = NULL;
1397                         }
1398                 }
1399                 if (rc || (bytes_read == 0)) {
1400                         if (total_read) {
1401                                 break;
1402                         } else {
1403                                 FreeXid(xid);
1404                                 return rc;
1405                         }
1406                 } else {
1407                         cifs_stats_bytes_read(pTcon, bytes_read);
1408                         *poffset += bytes_read;
1409                 }
1410         }
1411         FreeXid(xid);
1412         return total_read;
1413 }
1414
1415
1416 static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
1417         loff_t *poffset)
1418 {
1419         int rc = -EACCES;
1420         unsigned int bytes_read = 0;
1421         unsigned int total_read;
1422         unsigned int current_read_size;
1423         struct cifs_sb_info *cifs_sb;
1424         struct cifsTconInfo *pTcon;
1425         int xid;
1426         char *current_offset;
1427         struct cifsFileInfo *open_file;
1428
1429         xid = GetXid();
1430         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1431         pTcon = cifs_sb->tcon;
1432
1433         if (file->private_data == NULL) {
1434                 FreeXid(xid);
1435                 return -EBADF;
1436         }
1437         open_file = (struct cifsFileInfo *)file->private_data;
1438
1439         if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1440                 cFYI(1, ("attempting read on write only file instance"));
1441
1442         for (total_read = 0, current_offset = read_data;
1443              read_size > total_read;
1444              total_read += bytes_read, current_offset += bytes_read) {
1445                 current_read_size = min_t(const int, read_size - total_read,
1446                                           cifs_sb->rsize);
1447                 /* For windows me and 9x we do not want to request more
1448                 than it negotiated since it will refuse the read then */
1449                 if((pTcon->ses) &&
1450                         !(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
1451                         current_read_size = min_t(const int, current_read_size,
1452                                         pTcon->ses->server->maxBuf - 128);
1453                 }
1454                 rc = -EAGAIN;
1455                 while (rc == -EAGAIN) {
1456                         if ((open_file->invalidHandle) &&
1457                             (!open_file->closePend)) {
1458                                 rc = cifs_reopen_file(file->f_dentry->d_inode,
1459                                         file, TRUE);
1460                                 if (rc != 0)
1461                                         break;
1462                         }
1463                         rc = CIFSSMBRead(xid, pTcon,
1464                                         open_file->netfid,
1465                                         current_read_size, *poffset,
1466                                         &bytes_read, &current_offset);
1467                 }
1468                 if (rc || (bytes_read == 0)) {
1469                         if (total_read) {
1470                                 break;
1471                         } else {
1472                                 FreeXid(xid);
1473                                 return rc;
1474                         }
1475                 } else {
1476                         cifs_stats_bytes_read(pTcon, total_read);
1477                         *poffset += bytes_read;
1478                 }
1479         }
1480         FreeXid(xid);
1481         return total_read;
1482 }
1483
1484 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
1485 {
1486         struct dentry *dentry = file->f_dentry;
1487         int rc, xid;
1488
1489         xid = GetXid();
1490         rc = cifs_revalidate(dentry);
1491         if (rc) {
1492                 cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
1493                 FreeXid(xid);
1494                 return rc;
1495         }
1496         rc = generic_file_mmap(file, vma);
1497         FreeXid(xid);
1498         return rc;
1499 }
1500
1501
1502 static void cifs_copy_cache_pages(struct address_space *mapping,
1503         struct list_head *pages, int bytes_read, char *data,
1504         struct pagevec *plru_pvec)
1505 {
1506         struct page *page;
1507         char *target;
1508
1509         while (bytes_read > 0) {
1510                 if (list_empty(pages))
1511                         break;
1512
1513                 page = list_entry(pages->prev, struct page, lru);
1514                 list_del(&page->lru);
1515
1516                 if (add_to_page_cache(page, mapping, page->index,
1517                                       GFP_KERNEL)) {
1518                         page_cache_release(page);
1519                         cFYI(1, ("Add page cache failed"));
1520                         data += PAGE_CACHE_SIZE;
1521                         bytes_read -= PAGE_CACHE_SIZE;
1522                         continue;
1523                 }
1524
1525                 target = kmap_atomic(page,KM_USER0);
1526
1527                 if (PAGE_CACHE_SIZE > bytes_read) {
1528                         memcpy(target, data, bytes_read);
1529                         /* zero the tail end of this partial page */
1530                         memset(target + bytes_read, 0,
1531                                PAGE_CACHE_SIZE - bytes_read);
1532                         bytes_read = 0;
1533                 } else {
1534                         memcpy(target, data, PAGE_CACHE_SIZE);
1535                         bytes_read -= PAGE_CACHE_SIZE;
1536                 }
1537                 kunmap_atomic(target, KM_USER0);
1538
1539                 flush_dcache_page(page);
1540                 SetPageUptodate(page);
1541                 unlock_page(page);
1542                 if (!pagevec_add(plru_pvec, page))
1543                         __pagevec_lru_add(plru_pvec);
1544                 data += PAGE_CACHE_SIZE;
1545         }
1546         return;
1547 }
1548
1549 static int cifs_readpages(struct file *file, struct address_space *mapping,
1550         struct list_head *page_list, unsigned num_pages)
1551 {
1552         int rc = -EACCES;
1553         int xid;
1554         loff_t offset;
1555         struct page *page;
1556         struct cifs_sb_info *cifs_sb;
1557         struct cifsTconInfo *pTcon;
1558         int bytes_read = 0;
1559         unsigned int read_size,i;
1560         char *smb_read_data = NULL;
1561         struct smb_com_read_rsp *pSMBr;
1562         struct pagevec lru_pvec;
1563         struct cifsFileInfo *open_file;
1564
1565         xid = GetXid();
1566         if (file->private_data == NULL) {
1567                 FreeXid(xid);
1568                 return -EBADF;
1569         }
1570         open_file = (struct cifsFileInfo *)file->private_data;
1571         cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1572         pTcon = cifs_sb->tcon;
1573
1574         pagevec_init(&lru_pvec, 0);
1575
1576         for (i = 0; i < num_pages; ) {
1577                 unsigned contig_pages;
1578                 struct page *tmp_page;
1579                 unsigned long expected_index;
1580
1581                 if (list_empty(page_list))
1582                         break;
1583
1584                 page = list_entry(page_list->prev, struct page, lru);
1585                 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1586
1587                 /* count adjacent pages that we will read into */
1588                 contig_pages = 0;
1589                 expected_index =
1590                         list_entry(page_list->prev, struct page, lru)->index;
1591                 list_for_each_entry_reverse(tmp_page,page_list,lru) {
1592                         if (tmp_page->index == expected_index) {
1593                                 contig_pages++;
1594                                 expected_index++;
1595                         } else
1596                                 break;
1597                 }
1598                 if (contig_pages + i >  num_pages)
1599                         contig_pages = num_pages - i;
1600
1601                 /* for reads over a certain size could initiate async
1602                    read ahead */
1603
1604                 read_size = contig_pages * PAGE_CACHE_SIZE;
1605                 /* Read size needs to be in multiples of one page */
1606                 read_size = min_t(const unsigned int, read_size,
1607                                   cifs_sb->rsize & PAGE_CACHE_MASK);
1608
1609                 rc = -EAGAIN;
1610                 while (rc == -EAGAIN) {
1611                         if ((open_file->invalidHandle) &&
1612                             (!open_file->closePend)) {
1613                                 rc = cifs_reopen_file(file->f_dentry->d_inode,
1614                                         file, TRUE);
1615                                 if (rc != 0)
1616                                         break;
1617                         }
1618
1619                         rc = CIFSSMBRead(xid, pTcon,
1620                                         open_file->netfid,
1621                                         read_size, offset,
1622                                         &bytes_read, &smb_read_data);
1623
1624                         /* BB more RC checks ? */
1625                         if (rc== -EAGAIN) {
1626                                 if (smb_read_data) {
1627                                         cifs_buf_release(smb_read_data);
1628                                         smb_read_data = NULL;
1629                                 }
1630                         }
1631                 }
1632                 if ((rc < 0) || (smb_read_data == NULL)) {
1633                         cFYI(1, ("Read error in readpages: %d", rc));
1634                         /* clean up remaing pages off list */
1635                         while (!list_empty(page_list) && (i < num_pages)) {
1636                                 page = list_entry(page_list->prev, struct page,
1637                                                   lru);
1638                                 list_del(&page->lru);
1639                                 page_cache_release(page);
1640                         }
1641                         break;
1642                 } else if (bytes_read > 0) {
1643                         pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1644                         cifs_copy_cache_pages(mapping, page_list, bytes_read,
1645                                 smb_read_data + 4 /* RFC1001 hdr */ +
1646                                 le16_to_cpu(pSMBr->DataOffset), &lru_pvec);
1647
1648                         i +=  bytes_read >> PAGE_CACHE_SHIFT;
1649                         cifs_stats_bytes_read(pTcon, bytes_read);
1650                         if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
1651                                 i++; /* account for partial page */
1652
1653                                 /* server copy of file can have smaller size
1654                                    than client */
1655                                 /* BB do we need to verify this common case ?
1656                                    this case is ok - if we are at server EOF
1657                                    we will hit it on next read */
1658
1659                         /* while (!list_empty(page_list) && (i < num_pages)) {
1660                                         page = list_entry(page_list->prev,
1661                                                           struct page, list);
1662                                         list_del(&page->list);
1663                                         page_cache_release(page);
1664                                 }
1665                                 break; */
1666                         }
1667                 } else {
1668                         cFYI(1, ("No bytes read (%d) at offset %lld . "
1669                                  "Cleaning remaining pages from readahead list",
1670                                  bytes_read, offset));
1671                         /* BB turn off caching and do new lookup on
1672                            file size at server? */
1673                         while (!list_empty(page_list) && (i < num_pages)) {
1674                                 page = list_entry(page_list->prev, struct page,
1675                                                   lru);
1676                                 list_del(&page->lru);
1677
1678                                 /* BB removeme - replace with zero of page? */
1679                                 page_cache_release(page);
1680                         }
1681                         break;
1682                 }
1683                 if (smb_read_data) {
1684                         cifs_buf_release(smb_read_data);
1685                         smb_read_data = NULL;
1686                 }
1687                 bytes_read = 0;
1688         }
1689
1690         pagevec_lru_add(&lru_pvec);
1691
1692 /* need to free smb_read_data buf before exit */
1693         if (smb_read_data) {
1694                 cifs_buf_release(smb_read_data);
1695                 smb_read_data = NULL;
1696         }
1697
1698         FreeXid(xid);
1699         return rc;
1700 }
1701
1702 static int cifs_readpage_worker(struct file *file, struct page *page,
1703         loff_t *poffset)
1704 {
1705         char *read_data;
1706         int rc;
1707
1708         page_cache_get(page);
1709         read_data = kmap(page);
1710         /* for reads over a certain size could initiate async read ahead */
1711
1712         rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
1713
1714         if (rc < 0)
1715                 goto io_error;
1716         else
1717                 cFYI(1, ("Bytes read %d ",rc));
1718
1719         file->f_dentry->d_inode->i_atime =
1720                 current_fs_time(file->f_dentry->d_inode->i_sb);
1721
1722         if (PAGE_CACHE_SIZE > rc)
1723                 memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
1724
1725         flush_dcache_page(page);
1726         SetPageUptodate(page);
1727         rc = 0;
1728
1729 io_error:
1730         kunmap(page);
1731         page_cache_release(page);
1732         return rc;
1733 }
1734
1735 static int cifs_readpage(struct file *file, struct page *page)
1736 {
1737         loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1738         int rc = -EACCES;
1739         int xid;
1740
1741         xid = GetXid();
1742
1743         if (file->private_data == NULL) {
1744                 FreeXid(xid);
1745                 return -EBADF;
1746         }
1747
1748         cFYI(1, ("readpage %p at offset %d 0x%x\n",
1749                  page, (int)offset, (int)offset));
1750
1751         rc = cifs_readpage_worker(file, page, &offset);
1752
1753         unlock_page(page);
1754
1755         FreeXid(xid);
1756         return rc;
1757 }
1758
1759 /* We do not want to update the file size from server for inodes
1760    open for write - to avoid races with writepage extending
1761    the file - in the future we could consider allowing
1762    refreshing the inode only on increases in the file size
1763    but this is tricky to do without racing with writebehind
1764    page caching in the current Linux kernel design */
1765 int is_size_safe_to_change(struct cifsInodeInfo *cifsInode)
1766 {
1767         if (cifsInode && find_writable_file(cifsInode))
1768                 return 0;
1769         else
1770                 return 1;
1771 }
1772
1773 static int cifs_prepare_write(struct file *file, struct page *page,
1774         unsigned from, unsigned to)
1775 {
1776         int rc = 0;
1777         loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1778         cFYI(1, ("prepare write for page %p from %d to %d",page,from,to));
1779         if (!PageUptodate(page)) {
1780         /*      if (to - from != PAGE_CACHE_SIZE) {
1781                         void *kaddr = kmap_atomic(page, KM_USER0);
1782                         memset(kaddr, 0, from);
1783                         memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
1784                         flush_dcache_page(page);
1785                         kunmap_atomic(kaddr, KM_USER0);
1786                 } */
1787                 /* If we are writing a full page it will be up to date,
1788                    no need to read from the server */
1789                 if ((to == PAGE_CACHE_SIZE) && (from == 0))
1790                         SetPageUptodate(page);
1791
1792                 /* might as well read a page, it is fast enough */
1793                 if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
1794                         rc = cifs_readpage_worker(file, page, &offset);
1795                 } else {
1796                 /* should we try using another file handle if there is one -
1797                    how would we lock it to prevent close of that handle
1798                    racing with this read?
1799                    In any case this will be written out by commit_write */
1800                 }
1801         }
1802
1803         /* BB should we pass any errors back?
1804            e.g. if we do not have read access to the file */
1805         return 0;
1806 }
1807
1808 struct address_space_operations cifs_addr_ops = {
1809         .readpage = cifs_readpage,
1810         .readpages = cifs_readpages,
1811         .writepage = cifs_writepage,
1812 #ifdef CONFIG_CIFS_EXPERIMENTAL
1813         .writepages = cifs_writepages,
1814 #endif
1815         .prepare_write = cifs_prepare_write,
1816         .commit_write = cifs_commit_write,
1817         .set_page_dirty = __set_page_dirty_nobuffers,
1818         /* .sync_page = cifs_sync_page, */
1819         /* .direct_IO = */
1820 };