4 * vfs operations that deal with files
6 * Copyright (C) International Business Machines Corp., 2002,2003
7 * Author(s): Steve French (sfrench@us.ibm.com)
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.
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.
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
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 <linux/delay.h>
33 #include <asm/div64.h>
37 #include "cifsproto.h"
38 #include "cifs_unicode.h"
39 #include "cifs_debug.h"
40 #include "cifs_fs_sb.h"
42 static inline struct cifsFileInfo *cifs_init_private(
43 struct cifsFileInfo *private_data, struct inode *inode,
44 struct file *file, __u16 netfid)
46 memset(private_data, 0, sizeof(struct cifsFileInfo));
47 private_data->netfid = netfid;
48 private_data->pid = current->tgid;
49 init_MUTEX(&private_data->fh_sem);
50 private_data->pfile = file; /* needed for writepage */
51 private_data->pInode = inode;
52 private_data->invalidHandle = FALSE;
53 private_data->closePend = FALSE;
54 /* we have to track num writers to the inode, since writepages
55 does not tell us which handle the write is for so there can
56 be a close (overlapping with write) of the filehandle that
57 cifs_writepages chose to use */
58 atomic_set(&private_data->wrtPending,0);
63 static inline int cifs_convert_flags(unsigned int flags)
65 if ((flags & O_ACCMODE) == O_RDONLY)
67 else if ((flags & O_ACCMODE) == O_WRONLY)
69 else if ((flags & O_ACCMODE) == O_RDWR) {
70 /* GENERIC_ALL is too much permission to request
71 can cause unnecessary access denied on create */
72 /* return GENERIC_ALL; */
73 return (GENERIC_READ | GENERIC_WRITE);
79 static inline int cifs_get_disposition(unsigned int flags)
81 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
83 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
84 return FILE_OVERWRITE_IF;
85 else if ((flags & O_CREAT) == O_CREAT)
87 else if ((flags & O_TRUNC) == O_TRUNC)
88 return FILE_OVERWRITE;
93 /* all arguments to this function must be checked for validity in caller */
94 static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
95 struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile,
96 struct cifsTconInfo *pTcon, int *oplock, FILE_ALL_INFO *buf,
97 char *full_path, int xid)
102 /* want handles we can use to read with first
103 in the list so we do not have to walk the
104 list to search for one in prepare_write */
105 if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
106 list_add_tail(&pCifsFile->flist,
107 &pCifsInode->openFileList);
109 list_add(&pCifsFile->flist,
110 &pCifsInode->openFileList);
112 write_unlock(&GlobalSMBSeslock);
113 write_unlock(&file->f_owner.lock);
114 if (pCifsInode->clientCanCacheRead) {
115 /* we have the inode open somewhere else
116 no need to discard cache data */
117 goto client_can_cache;
120 /* BB need same check in cifs_create too? */
121 /* if not oplocked, invalidate inode pages if mtime or file
123 temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime));
124 if (timespec_equal(&file->f_dentry->d_inode->i_mtime, &temp) &&
125 (file->f_dentry->d_inode->i_size ==
126 (loff_t)le64_to_cpu(buf->EndOfFile))) {
127 cFYI(1, ("inode unchanged on server"));
129 if (file->f_dentry->d_inode->i_mapping) {
130 /* BB no need to lock inode until after invalidate
131 since namei code should already have it locked? */
132 filemap_write_and_wait(file->f_dentry->d_inode->i_mapping);
134 cFYI(1, ("invalidating remote inode since open detected it "
136 invalidate_remote_inode(file->f_dentry->d_inode);
140 if (pTcon->ses->capabilities & CAP_UNIX)
141 rc = cifs_get_inode_info_unix(&file->f_dentry->d_inode,
142 full_path, inode->i_sb, xid);
144 rc = cifs_get_inode_info(&file->f_dentry->d_inode,
145 full_path, buf, inode->i_sb, xid);
147 if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) {
148 pCifsInode->clientCanCacheAll = TRUE;
149 pCifsInode->clientCanCacheRead = TRUE;
150 cFYI(1, ("Exclusive Oplock granted on inode %p",
151 file->f_dentry->d_inode));
152 } else if ((*oplock & 0xF) == OPLOCK_READ)
153 pCifsInode->clientCanCacheRead = TRUE;
158 int cifs_open(struct inode *inode, struct file *file)
162 struct cifs_sb_info *cifs_sb;
163 struct cifsTconInfo *pTcon;
164 struct cifsFileInfo *pCifsFile;
165 struct cifsInodeInfo *pCifsInode;
166 struct list_head *tmp;
167 char *full_path = NULL;
171 FILE_ALL_INFO *buf = NULL;
175 cifs_sb = CIFS_SB(inode->i_sb);
176 pTcon = cifs_sb->tcon;
178 if (file->f_flags & O_CREAT) {
179 /* search inode for this file and fill in file->private_data */
180 pCifsInode = CIFS_I(file->f_dentry->d_inode);
181 read_lock(&GlobalSMBSeslock);
182 list_for_each(tmp, &pCifsInode->openFileList) {
183 pCifsFile = list_entry(tmp, struct cifsFileInfo,
185 if ((pCifsFile->pfile == NULL) &&
186 (pCifsFile->pid == current->tgid)) {
187 /* mode set in cifs_create */
189 /* needed for writepage */
190 pCifsFile->pfile = file;
192 file->private_data = pCifsFile;
196 read_unlock(&GlobalSMBSeslock);
197 if (file->private_data != NULL) {
202 if (file->f_flags & O_EXCL)
203 cERROR(1, ("could not find file instance for "
204 "new file %p", file));
208 full_path = build_path_from_dentry(file->f_dentry);
209 if (full_path == NULL) {
214 cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
215 inode, file->f_flags, full_path));
216 desiredAccess = cifs_convert_flags(file->f_flags);
218 /*********************************************************************
219 * open flag mapping table:
221 * POSIX Flag CIFS Disposition
222 * ---------- ----------------
223 * O_CREAT FILE_OPEN_IF
224 * O_CREAT | O_EXCL FILE_CREATE
225 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
226 * O_TRUNC FILE_OVERWRITE
227 * none of the above FILE_OPEN
229 * Note that there is not a direct match between disposition
230 * FILE_SUPERSEDE (ie create whether or not file exists although
231 * O_CREAT | O_TRUNC is similar but truncates the existing
232 * file rather than creating a new file as FILE_SUPERSEDE does
233 * (which uses the attributes / metadata passed in on open call)
235 *? O_SYNC is a reasonable match to CIFS writethrough flag
236 *? and the read write flags match reasonably. O_LARGEFILE
237 *? is irrelevant because largefile support is always used
238 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
239 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
240 *********************************************************************/
242 disposition = cifs_get_disposition(file->f_flags);
249 /* BB pass O_SYNC flag through on file attributes .. BB */
251 /* Also refresh inode by passing in file_info buf returned by SMBOpen
252 and calling get_inode_info with returned buf (at least helps
253 non-Unix server case) */
255 /* BB we can not do this if this is the second open of a file
256 and the first handle has writebehind data, we might be
257 able to simply do a filemap_fdatawrite/filemap_fdatawait first */
258 buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
264 if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS)
265 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition,
266 desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
267 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
268 & CIFS_MOUNT_MAP_SPECIAL_CHR);
270 rc = -EIO; /* no NT SMB support fall into legacy open below */
273 /* Old server, try legacy style OpenX */
274 rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
275 desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
276 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
277 & CIFS_MOUNT_MAP_SPECIAL_CHR);
280 cFYI(1, ("cifs_open returned 0x%x", rc));
284 kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
285 if (file->private_data == NULL) {
289 pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
290 write_lock(&file->f_owner.lock);
291 write_lock(&GlobalSMBSeslock);
292 list_add(&pCifsFile->tlist, &pTcon->openFileList);
294 pCifsInode = CIFS_I(file->f_dentry->d_inode);
296 rc = cifs_open_inode_helper(inode, file, pCifsInode,
298 &oplock, buf, full_path, xid);
300 write_unlock(&GlobalSMBSeslock);
301 write_unlock(&file->f_owner.lock);
304 if (oplock & CIFS_CREATE_ACTION) {
305 /* time to set mode which we can not set earlier due to
306 problems creating new read-only files */
307 if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
308 CIFSSMBUnixSetPerms(xid, pTcon, full_path,
310 (__u64)-1, (__u64)-1, 0 /* dev */,
312 cifs_sb->mnt_cifs_flags &
313 CIFS_MOUNT_MAP_SPECIAL_CHR);
315 /* BB implement via Windows security descriptors eg
316 CIFSSMBWinSetPerms(xid, pTcon, full_path, mode,
318 in the meantime could set r/o dos attribute when
319 perms are eg: mode & 0222 == 0 */
330 /* Try to reaquire byte range locks that were released when session */
331 /* to server was lost */
332 static int cifs_relock_file(struct cifsFileInfo *cifsFile)
336 /* BB list all locks open on this file and relock */
341 static int cifs_reopen_file(struct inode *inode, struct file *file,
346 struct cifs_sb_info *cifs_sb;
347 struct cifsTconInfo *pTcon;
348 struct cifsFileInfo *pCifsFile;
349 struct cifsInodeInfo *pCifsInode;
350 char *full_path = NULL;
352 int disposition = FILE_OPEN;
357 if (file->private_data) {
358 pCifsFile = (struct cifsFileInfo *)file->private_data;
363 down(&pCifsFile->fh_sem);
364 if (pCifsFile->invalidHandle == FALSE) {
365 up(&pCifsFile->fh_sem);
370 if (file->f_dentry == NULL) {
371 up(&pCifsFile->fh_sem);
372 cFYI(1, ("failed file reopen, no valid name if dentry freed"));
376 cifs_sb = CIFS_SB(inode->i_sb);
377 pTcon = cifs_sb->tcon;
378 /* can not grab rename sem here because various ops, including
379 those that already have the rename sem can end up causing writepage
380 to get called and if the server was down that means we end up here,
381 and we can never tell if the caller already has the rename_sem */
382 full_path = build_path_from_dentry(file->f_dentry);
383 if (full_path == NULL) {
384 up(&pCifsFile->fh_sem);
389 cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
390 inode, file->f_flags,full_path));
391 desiredAccess = cifs_convert_flags(file->f_flags);
398 /* Can not refresh inode by passing in file_info buf to be returned
399 by SMBOpen and then calling get_inode_info with returned buf
400 since file might have write behind data that needs to be flushed
401 and server version of file size can be stale. If we knew for sure
402 that inode was not dirty locally we could do this */
404 /* buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
406 up(&pCifsFile->fh_sem);
411 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
412 CREATE_NOT_DIR, &netfid, &oplock, NULL,
413 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
414 CIFS_MOUNT_MAP_SPECIAL_CHR);
416 up(&pCifsFile->fh_sem);
417 cFYI(1, ("cifs_open returned 0x%x", rc));
418 cFYI(1, ("oplock: %d", oplock));
420 pCifsFile->netfid = netfid;
421 pCifsFile->invalidHandle = FALSE;
422 up(&pCifsFile->fh_sem);
423 pCifsInode = CIFS_I(inode);
426 filemap_write_and_wait(inode->i_mapping);
427 /* temporarily disable caching while we
428 go to server to get inode info */
429 pCifsInode->clientCanCacheAll = FALSE;
430 pCifsInode->clientCanCacheRead = FALSE;
431 if (pTcon->ses->capabilities & CAP_UNIX)
432 rc = cifs_get_inode_info_unix(&inode,
433 full_path, inode->i_sb, xid);
435 rc = cifs_get_inode_info(&inode,
436 full_path, NULL, inode->i_sb,
438 } /* else we are writing out data to server already
439 and could deadlock if we tried to flush data, and
440 since we do not know if we have data that would
441 invalidate the current end of file on the server
442 we can not go to the server to get the new inod
444 if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
445 pCifsInode->clientCanCacheAll = TRUE;
446 pCifsInode->clientCanCacheRead = TRUE;
447 cFYI(1, ("Exclusive Oplock granted on inode %p",
448 file->f_dentry->d_inode));
449 } else if ((oplock & 0xF) == OPLOCK_READ) {
450 pCifsInode->clientCanCacheRead = TRUE;
451 pCifsInode->clientCanCacheAll = FALSE;
453 pCifsInode->clientCanCacheRead = FALSE;
454 pCifsInode->clientCanCacheAll = FALSE;
456 cifs_relock_file(pCifsFile);
465 int cifs_close(struct inode *inode, struct file *file)
469 struct cifs_sb_info *cifs_sb;
470 struct cifsTconInfo *pTcon;
471 struct cifsFileInfo *pSMBFile =
472 (struct cifsFileInfo *)file->private_data;
476 cifs_sb = CIFS_SB(inode->i_sb);
477 pTcon = cifs_sb->tcon;
479 pSMBFile->closePend = TRUE;
480 write_lock(&file->f_owner.lock);
482 /* no sense reconnecting to close a file that is
484 if (pTcon->tidStatus != CifsNeedReconnect) {
486 while((atomic_read(&pSMBFile->wrtPending) != 0)
487 && (timeout < 1000) ) {
488 /* Give write a better chance to get to
489 server ahead of the close. We do not
490 want to add a wait_q here as it would
491 increase the memory utilization as
492 the struct would be in each open file,
493 but this should give enough time to
495 write_unlock(&file->f_owner.lock);
496 cERROR(1,("close with pending writes"));
498 write_lock(&file->f_owner.lock);
501 write_unlock(&file->f_owner.lock);
502 rc = CIFSSMBClose(xid, pTcon,
504 write_lock(&file->f_owner.lock);
507 write_lock(&GlobalSMBSeslock);
508 list_del(&pSMBFile->flist);
509 list_del(&pSMBFile->tlist);
510 write_unlock(&GlobalSMBSeslock);
511 write_unlock(&file->f_owner.lock);
512 kfree(pSMBFile->search_resume_name);
513 kfree(file->private_data);
514 file->private_data = NULL;
518 if (list_empty(&(CIFS_I(inode)->openFileList))) {
519 cFYI(1, ("closing last open instance for inode %p", inode));
520 /* if the file is not open we do not know if we can cache info
521 on this inode, much less write behind and read ahead */
522 CIFS_I(inode)->clientCanCacheRead = FALSE;
523 CIFS_I(inode)->clientCanCacheAll = FALSE;
525 if ((rc ==0) && CIFS_I(inode)->write_behind_rc)
526 rc = CIFS_I(inode)->write_behind_rc;
531 int cifs_closedir(struct inode *inode, struct file *file)
535 struct cifsFileInfo *pCFileStruct =
536 (struct cifsFileInfo *)file->private_data;
539 cFYI(1, ("Closedir inode = 0x%p", inode));
544 struct cifsTconInfo *pTcon;
545 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_dentry->d_sb);
547 pTcon = cifs_sb->tcon;
549 cFYI(1, ("Freeing private data in close dir"));
550 if ((pCFileStruct->srch_inf.endOfSearch == FALSE) &&
551 (pCFileStruct->invalidHandle == FALSE)) {
552 pCFileStruct->invalidHandle = TRUE;
553 rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
554 cFYI(1, ("Closing uncompleted readdir with rc %d",
556 /* not much we can do if it fails anyway, ignore rc */
559 ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
561 cFYI(1, ("closedir free smb buf in srch struct"));
562 pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
563 if(pCFileStruct->srch_inf.smallBuf)
564 cifs_small_buf_release(ptmp);
566 cifs_buf_release(ptmp);
568 ptmp = pCFileStruct->search_resume_name;
570 cFYI(1, ("closedir free resume name"));
571 pCFileStruct->search_resume_name = NULL;
574 kfree(file->private_data);
575 file->private_data = NULL;
577 /* BB can we lock the filestruct while this is going on? */
582 int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
588 int wait_flag = FALSE;
589 struct cifs_sb_info *cifs_sb;
590 struct cifsTconInfo *pTcon;
592 __u8 lockType = LOCKING_ANDX_LARGE_FILES;
594 length = 1 + pfLock->fl_end - pfLock->fl_start;
598 cFYI(1, ("Lock parm: 0x%x flockflags: "
599 "0x%x flocktype: 0x%x start: %lld end: %lld",
600 cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
603 if (pfLock->fl_flags & FL_POSIX)
605 if (pfLock->fl_flags & FL_FLOCK)
607 if (pfLock->fl_flags & FL_SLEEP) {
608 cFYI(1, ("Blocking lock"));
611 if (pfLock->fl_flags & FL_ACCESS)
612 cFYI(1, ("Process suspended by mandatory locking - "
613 "not implemented yet"));
614 if (pfLock->fl_flags & FL_LEASE)
615 cFYI(1, ("Lease on file - not implemented yet"));
616 if (pfLock->fl_flags &
617 (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
618 cFYI(1, ("Unknown lock flags 0x%x", pfLock->fl_flags));
620 if (pfLock->fl_type == F_WRLCK) {
621 cFYI(1, ("F_WRLCK "));
623 } else if (pfLock->fl_type == F_UNLCK) {
624 cFYI(1, ("F_UNLCK"));
626 /* Check if unlock includes more than
628 } else if (pfLock->fl_type == F_RDLCK) {
629 cFYI(1, ("F_RDLCK"));
630 lockType |= LOCKING_ANDX_SHARED_LOCK;
632 } else if (pfLock->fl_type == F_EXLCK) {
633 cFYI(1, ("F_EXLCK"));
635 } else if (pfLock->fl_type == F_SHLCK) {
636 cFYI(1, ("F_SHLCK"));
637 lockType |= LOCKING_ANDX_SHARED_LOCK;
640 cFYI(1, ("Unknown type of lock"));
642 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
643 pTcon = cifs_sb->tcon;
645 if (file->private_data == NULL) {
649 netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
652 /* BB add code here to normalize offset and length to
653 account for negative length which we can not accept over the
657 (cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
658 (CIFS_UNIX_FCNTL_CAP &
659 le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability))) {
661 if(lockType & LOCKING_ANDX_SHARED_LOCK)
662 posix_lock_type = CIFS_RDLCK;
664 posix_lock_type = CIFS_WRLCK;
665 rc = CIFSSMBPosixLock(xid, pTcon, netfid, 1 /* get */,
667 posix_lock_type, wait_flag);
672 /* BB we could chain these into one lock request BB */
673 rc = CIFSSMBLock(xid, pTcon, netfid, length, pfLock->fl_start,
674 0, 1, lockType, 0 /* wait flag */ );
676 rc = CIFSSMBLock(xid, pTcon, netfid, length,
677 pfLock->fl_start, 1 /* numUnlock */ ,
678 0 /* numLock */ , lockType,
680 pfLock->fl_type = F_UNLCK;
682 cERROR(1, ("Error unlocking previously locked "
683 "range %d during test of lock", rc));
687 /* if rc == ERR_SHARING_VIOLATION ? */
688 rc = 0; /* do not change lock type to unlock
689 since range in use */
695 if (experimEnabled &&
696 (cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
697 (CIFS_UNIX_FCNTL_CAP &
698 le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability))) {
700 if(lockType & LOCKING_ANDX_SHARED_LOCK)
701 posix_lock_type = CIFS_RDLCK;
703 posix_lock_type = CIFS_WRLCK;
706 posix_lock_type = CIFS_UNLCK;
707 else if(numLock == 0) {
708 /* if no lock or unlock then nothing
709 to do since we do not know what it is */
713 rc = CIFSSMBPosixLock(xid, pTcon, netfid, 0 /* set */,
715 posix_lock_type, wait_flag);
717 rc = CIFSSMBLock(xid, pTcon, netfid, length, pfLock->fl_start,
718 numUnlock, numLock, lockType, wait_flag);
719 if (pfLock->fl_flags & FL_POSIX)
720 posix_lock_file_wait(file, pfLock);
725 ssize_t cifs_user_write(struct file *file, const char __user *write_data,
726 size_t write_size, loff_t *poffset)
729 unsigned int bytes_written = 0;
730 unsigned int total_written;
731 struct cifs_sb_info *cifs_sb;
732 struct cifsTconInfo *pTcon;
734 struct cifsFileInfo *open_file;
736 if (file->f_dentry == NULL)
739 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
743 pTcon = cifs_sb->tcon;
746 (" write %d bytes to offset %lld of %s", write_size,
747 *poffset, file->f_dentry->d_name.name)); */
749 if (file->private_data == NULL)
752 open_file = (struct cifsFileInfo *) file->private_data;
755 if (file->f_dentry->d_inode == NULL) {
760 if (*poffset > file->f_dentry->d_inode->i_size)
761 long_op = 2; /* writes past end of file can take a long time */
765 for (total_written = 0; write_size > total_written;
766 total_written += bytes_written) {
768 while (rc == -EAGAIN) {
769 if (file->private_data == NULL) {
770 /* file has been closed on us */
772 /* if we have gotten here we have written some data
773 and blocked, and the file has been freed on us while
774 we blocked so return what we managed to write */
775 return total_written;
777 if (open_file->closePend) {
780 return total_written;
784 if (open_file->invalidHandle) {
785 if ((file->f_dentry == NULL) ||
786 (file->f_dentry->d_inode == NULL)) {
788 return total_written;
790 /* we could deadlock if we called
791 filemap_fdatawait from here so tell
792 reopen_file not to flush data to server
794 rc = cifs_reopen_file(file->f_dentry->d_inode,
800 rc = CIFSSMBWrite(xid, pTcon,
802 min_t(const int, cifs_sb->wsize,
803 write_size - total_written),
804 *poffset, &bytes_written,
805 NULL, write_data + total_written, long_op);
807 if (rc || (bytes_written == 0)) {
815 *poffset += bytes_written;
816 long_op = FALSE; /* subsequent writes fast -
817 15 seconds is plenty */
820 cifs_stats_bytes_written(pTcon, total_written);
822 /* since the write may have blocked check these pointers again */
823 if (file->f_dentry) {
824 if (file->f_dentry->d_inode) {
825 struct inode *inode = file->f_dentry->d_inode;
826 inode->i_ctime = inode->i_mtime =
827 current_fs_time(inode->i_sb);
828 if (total_written > 0) {
829 if (*poffset > file->f_dentry->d_inode->i_size)
830 i_size_write(file->f_dentry->d_inode,
833 mark_inode_dirty_sync(file->f_dentry->d_inode);
837 return total_written;
840 static ssize_t cifs_write(struct file *file, const char *write_data,
841 size_t write_size, loff_t *poffset)
844 unsigned int bytes_written = 0;
845 unsigned int total_written;
846 struct cifs_sb_info *cifs_sb;
847 struct cifsTconInfo *pTcon;
849 struct cifsFileInfo *open_file;
851 if (file->f_dentry == NULL)
854 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
858 pTcon = cifs_sb->tcon;
860 cFYI(1,("write %zd bytes to offset %lld of %s", write_size,
861 *poffset, file->f_dentry->d_name.name));
863 if (file->private_data == NULL)
866 open_file = (struct cifsFileInfo *)file->private_data;
869 if (file->f_dentry->d_inode == NULL) {
874 if (*poffset > file->f_dentry->d_inode->i_size)
875 long_op = 2; /* writes past end of file can take a long time */
879 for (total_written = 0; write_size > total_written;
880 total_written += bytes_written) {
882 while (rc == -EAGAIN) {
883 if (file->private_data == NULL) {
884 /* file has been closed on us */
886 /* if we have gotten here we have written some data
887 and blocked, and the file has been freed on us
888 while we blocked so return what we managed to
890 return total_written;
892 if (open_file->closePend) {
895 return total_written;
899 if (open_file->invalidHandle) {
900 if ((file->f_dentry == NULL) ||
901 (file->f_dentry->d_inode == NULL)) {
903 return total_written;
905 /* we could deadlock if we called
906 filemap_fdatawait from here so tell
907 reopen_file not to flush data to
909 rc = cifs_reopen_file(file->f_dentry->d_inode,
914 if(experimEnabled || (pTcon->ses->server &&
915 ((pTcon->ses->server->secMode &
916 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
921 len = min((size_t)cifs_sb->wsize,
922 write_size - total_written);
923 /* iov[0] is reserved for smb header */
924 iov[1].iov_base = (char *)write_data +
926 iov[1].iov_len = len;
927 rc = CIFSSMBWrite2(xid, pTcon,
928 open_file->netfid, len,
929 *poffset, &bytes_written,
932 rc = CIFSSMBWrite(xid, pTcon,
934 min_t(const int, cifs_sb->wsize,
935 write_size - total_written),
936 *poffset, &bytes_written,
937 write_data + total_written,
940 if (rc || (bytes_written == 0)) {
948 *poffset += bytes_written;
949 long_op = FALSE; /* subsequent writes fast -
950 15 seconds is plenty */
953 cifs_stats_bytes_written(pTcon, total_written);
955 /* since the write may have blocked check these pointers again */
956 if (file->f_dentry) {
957 if (file->f_dentry->d_inode) {
958 file->f_dentry->d_inode->i_ctime =
959 file->f_dentry->d_inode->i_mtime = CURRENT_TIME;
960 if (total_written > 0) {
961 if (*poffset > file->f_dentry->d_inode->i_size)
962 i_size_write(file->f_dentry->d_inode,
965 mark_inode_dirty_sync(file->f_dentry->d_inode);
969 return total_written;
972 struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
974 struct cifsFileInfo *open_file;
977 /* Having a null inode here (because mapping->host was set to zero by
978 the VFS or MM) should not happen but we had reports of on oops (due to
979 it being zero) during stress testcases so we need to check for it */
981 if(cifs_inode == NULL) {
982 cERROR(1,("Null inode passed to cifs_writeable_file"));
987 read_lock(&GlobalSMBSeslock);
988 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
989 if (open_file->closePend)
991 if (open_file->pfile &&
992 ((open_file->pfile->f_flags & O_RDWR) ||
993 (open_file->pfile->f_flags & O_WRONLY))) {
994 atomic_inc(&open_file->wrtPending);
995 read_unlock(&GlobalSMBSeslock);
996 if((open_file->invalidHandle) &&
997 (!open_file->closePend) /* BB fixme -since the second clause can not be true remove it BB */) {
998 rc = cifs_reopen_file(&cifs_inode->vfs_inode,
999 open_file->pfile, FALSE);
1000 /* if it fails, try another handle - might be */
1001 /* dangerous to hold up writepages with retry */
1003 cFYI(1,("failed on reopen file in wp"));
1004 read_lock(&GlobalSMBSeslock);
1005 /* can not use this handle, no write
1006 pending on this one after all */
1008 (&open_file->wrtPending);
1015 read_unlock(&GlobalSMBSeslock);
1019 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
1021 struct address_space *mapping = page->mapping;
1022 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1025 int bytes_written = 0;
1026 struct cifs_sb_info *cifs_sb;
1027 struct cifsTconInfo *pTcon;
1028 struct inode *inode;
1029 struct cifsFileInfo *open_file;
1031 if (!mapping || !mapping->host)
1034 inode = page->mapping->host;
1035 cifs_sb = CIFS_SB(inode->i_sb);
1036 pTcon = cifs_sb->tcon;
1038 offset += (loff_t)from;
1039 write_data = kmap(page);
1042 if ((to > PAGE_CACHE_SIZE) || (from > to)) {
1047 /* racing with truncate? */
1048 if (offset > mapping->host->i_size) {
1050 return 0; /* don't care */
1053 /* check to make sure that we are not extending the file */
1054 if (mapping->host->i_size - offset < (loff_t)to)
1055 to = (unsigned)(mapping->host->i_size - offset);
1057 open_file = find_writable_file(CIFS_I(mapping->host));
1059 bytes_written = cifs_write(open_file->pfile, write_data,
1061 atomic_dec(&open_file->wrtPending);
1062 /* Does mm or vfs already set times? */
1063 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1064 if ((bytes_written > 0) && (offset)) {
1066 } else if (bytes_written < 0) {
1071 cFYI(1, ("No writeable filehandles for inode"));
1079 static int cifs_writepages(struct address_space *mapping,
1080 struct writeback_control *wbc)
1082 struct backing_dev_info *bdi = mapping->backing_dev_info;
1083 unsigned int bytes_to_write;
1084 unsigned int bytes_written;
1085 struct cifs_sb_info *cifs_sb;
1089 int range_whole = 0;
1090 struct kvec iov[32];
1096 struct cifsFileInfo *open_file;
1098 struct pagevec pvec;
1103 cifs_sb = CIFS_SB(mapping->host->i_sb);
1106 * If wsize is smaller that the page cache size, default to writing
1107 * one page at a time via cifs_writepage
1109 if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1110 return generic_writepages(mapping, wbc);
1112 if((cifs_sb->tcon->ses) && (cifs_sb->tcon->ses->server))
1113 if(cifs_sb->tcon->ses->server->secMode &
1114 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
1116 return generic_writepages(mapping, wbc);
1119 * BB: Is this meaningful for a non-block-device file system?
1120 * If it is, we should test it again after we do I/O
1122 if (wbc->nonblocking && bdi_write_congested(bdi)) {
1123 wbc->encountered_congestion = 1;
1129 pagevec_init(&pvec, 0);
1130 if (wbc->range_cyclic) {
1131 index = mapping->writeback_index; /* Start from prev offset */
1134 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1135 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1136 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1141 while (!done && (index <= end) &&
1142 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
1143 PAGECACHE_TAG_DIRTY,
1144 min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
1153 for (i = 0; i < nr_pages; i++) {
1154 page = pvec.pages[i];
1156 * At this point we hold neither mapping->tree_lock nor
1157 * lock on the page itself: the page may be truncated or
1158 * invalidated (changing page->mapping to NULL), or even
1159 * swizzled back from swapper_space to tmpfs file
1165 else if (TestSetPageLocked(page))
1168 if (unlikely(page->mapping != mapping)) {
1173 if (!wbc->range_cyclic && page->index > end) {
1179 if (next && (page->index != next)) {
1180 /* Not next consecutive page */
1185 if (wbc->sync_mode != WB_SYNC_NONE)
1186 wait_on_page_writeback(page);
1188 if (PageWriteback(page) ||
1189 !test_clear_page_dirty(page)) {
1194 if (page_offset(page) >= mapping->host->i_size) {
1201 * BB can we get rid of this? pages are held by pvec
1203 page_cache_get(page);
1205 len = min(mapping->host->i_size - page_offset(page),
1206 (loff_t)PAGE_CACHE_SIZE);
1208 /* reserve iov[0] for the smb header */
1210 iov[n_iov].iov_base = kmap(page);
1211 iov[n_iov].iov_len = len;
1212 bytes_to_write += len;
1216 offset = page_offset(page);
1218 next = page->index + 1;
1219 if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
1223 /* Search for a writable handle every time we call
1224 * CIFSSMBWrite2. We can't rely on the last handle
1225 * we used to still be valid
1227 open_file = find_writable_file(CIFS_I(mapping->host));
1229 cERROR(1, ("No writable handles for inode"));
1232 rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
1234 bytes_to_write, offset,
1235 &bytes_written, iov, n_iov,
1237 atomic_dec(&open_file->wrtPending);
1238 if (rc || bytes_written < bytes_to_write) {
1239 cERROR(1,("Write2 ret %d, written = %d",
1240 rc, bytes_written));
1241 /* BB what if continued retry is
1242 requested via mount flags? */
1243 set_bit(AS_EIO, &mapping->flags);
1245 cifs_stats_bytes_written(cifs_sb->tcon,
1249 for (i = 0; i < n_iov; i++) {
1250 page = pvec.pages[first + i];
1251 /* Should we also set page error on
1252 success rc but too little data written? */
1253 /* BB investigate retry logic on temporary
1254 server crash cases and how recovery works
1255 when page marked as error */
1260 page_cache_release(page);
1262 if ((wbc->nr_to_write -= n_iov) <= 0)
1266 pagevec_release(&pvec);
1268 if (!scanned && !done) {
1270 * We hit the last page and there is more work to be done: wrap
1271 * back to the start of the file
1277 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1278 mapping->writeback_index = index;
1285 static int cifs_writepage(struct page* page, struct writeback_control *wbc)
1291 /* BB add check for wbc flags */
1292 page_cache_get(page);
1293 if (!PageUptodate(page)) {
1294 cFYI(1, ("ppw - page not up to date"));
1297 rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1298 SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
1300 page_cache_release(page);
1305 static int cifs_commit_write(struct file *file, struct page *page,
1306 unsigned offset, unsigned to)
1310 struct inode *inode = page->mapping->host;
1311 loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
1315 cFYI(1, ("commit write for page %p up to position %lld for %d",
1316 page, position, to));
1317 if (position > inode->i_size) {
1318 i_size_write(inode, position);
1319 /* if (file->private_data == NULL) {
1322 open_file = (struct cifsFileInfo *)file->private_data;
1323 cifs_sb = CIFS_SB(inode->i_sb);
1325 while (rc == -EAGAIN) {
1326 if ((open_file->invalidHandle) &&
1327 (!open_file->closePend)) {
1328 rc = cifs_reopen_file(
1329 file->f_dentry->d_inode, file);
1333 if (!open_file->closePend) {
1334 rc = CIFSSMBSetFileSize(xid,
1335 cifs_sb->tcon, position,
1337 open_file->pid, FALSE);
1343 cFYI(1, (" SetEOF (commit write) rc = %d", rc));
1346 if (!PageUptodate(page)) {
1347 position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset;
1348 /* can not rely on (or let) writepage write this data */
1350 cFYI(1, ("Illegal offsets, can not copy from %d to %d",
1355 /* this is probably better than directly calling
1356 partialpage_write since in this function the file handle is
1357 known which we might as well leverage */
1358 /* BB check if anything else missing out of ppw
1359 such as updating last write time */
1360 page_data = kmap(page);
1361 rc = cifs_write(file, page_data + offset, to-offset,
1365 /* else if (rc < 0) should we set writebehind rc? */
1368 set_page_dirty(page);
1375 int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
1379 struct inode *inode = file->f_dentry->d_inode;
1383 cFYI(1, ("Sync file - name: %s datasync: 0x%x",
1384 dentry->d_name.name, datasync));
1386 rc = filemap_fdatawrite(inode->i_mapping);
1388 CIFS_I(inode)->write_behind_rc = 0;
1393 /* static void cifs_sync_page(struct page *page)
1395 struct address_space *mapping;
1396 struct inode *inode;
1397 unsigned long index = page->index;
1398 unsigned int rpages = 0;
1401 cFYI(1, ("sync page %p",page));
1402 mapping = page->mapping;
1405 inode = mapping->host;
1409 /* fill in rpages then
1410 result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
1412 /* cFYI(1, ("rpages is %d for sync page of Index %ld", rpages, index));
1422 * As file closes, flush all cached write data for this inode checking
1423 * for write behind errors.
1425 int cifs_flush(struct file *file, fl_owner_t id)
1427 struct inode * inode = file->f_dentry->d_inode;
1430 /* Rather than do the steps manually:
1431 lock the inode for writing
1432 loop through pages looking for write behind data (dirty pages)
1433 coalesce into contiguous 16K (or smaller) chunks to write to server
1434 send to server (prefer in parallel)
1435 deal with writebehind errors
1436 unlock inode for writing
1437 filemapfdatawrite appears easier for the time being */
1439 rc = filemap_fdatawrite(inode->i_mapping);
1440 if (!rc) /* reset wb rc if we were able to write out dirty pages */
1441 CIFS_I(inode)->write_behind_rc = 0;
1443 cFYI(1, ("Flush inode %p file %p rc %d",inode,file,rc));
1448 ssize_t cifs_user_read(struct file *file, char __user *read_data,
1449 size_t read_size, loff_t *poffset)
1452 unsigned int bytes_read = 0;
1453 unsigned int total_read = 0;
1454 unsigned int current_read_size;
1455 struct cifs_sb_info *cifs_sb;
1456 struct cifsTconInfo *pTcon;
1458 struct cifsFileInfo *open_file;
1459 char *smb_read_data;
1460 char __user *current_offset;
1461 struct smb_com_read_rsp *pSMBr;
1464 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1465 pTcon = cifs_sb->tcon;
1467 if (file->private_data == NULL) {
1471 open_file = (struct cifsFileInfo *)file->private_data;
1473 if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
1474 cFYI(1, ("attempting read on write only file instance"));
1476 for (total_read = 0, current_offset = read_data;
1477 read_size > total_read;
1478 total_read += bytes_read, current_offset += bytes_read) {
1479 current_read_size = min_t(const int, read_size - total_read,
1482 smb_read_data = NULL;
1483 while (rc == -EAGAIN) {
1484 int buf_type = CIFS_NO_BUFFER;
1485 if ((open_file->invalidHandle) &&
1486 (!open_file->closePend)) {
1487 rc = cifs_reopen_file(file->f_dentry->d_inode,
1492 rc = CIFSSMBRead(xid, pTcon,
1494 current_read_size, *poffset,
1495 &bytes_read, &smb_read_data,
1497 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1498 if (smb_read_data) {
1499 if (copy_to_user(current_offset,
1501 4 /* RFC1001 length field */ +
1502 le16_to_cpu(pSMBr->DataOffset),
1507 if(buf_type == CIFS_SMALL_BUFFER)
1508 cifs_small_buf_release(smb_read_data);
1509 else if(buf_type == CIFS_LARGE_BUFFER)
1510 cifs_buf_release(smb_read_data);
1511 smb_read_data = NULL;
1514 if (rc || (bytes_read == 0)) {
1522 cifs_stats_bytes_read(pTcon, bytes_read);
1523 *poffset += bytes_read;
1531 static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
1535 unsigned int bytes_read = 0;
1536 unsigned int total_read;
1537 unsigned int current_read_size;
1538 struct cifs_sb_info *cifs_sb;
1539 struct cifsTconInfo *pTcon;
1541 char *current_offset;
1542 struct cifsFileInfo *open_file;
1543 int buf_type = CIFS_NO_BUFFER;
1546 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1547 pTcon = cifs_sb->tcon;
1549 if (file->private_data == NULL) {
1553 open_file = (struct cifsFileInfo *)file->private_data;
1555 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1556 cFYI(1, ("attempting read on write only file instance"));
1558 for (total_read = 0, current_offset = read_data;
1559 read_size > total_read;
1560 total_read += bytes_read, current_offset += bytes_read) {
1561 current_read_size = min_t(const int, read_size - total_read,
1563 /* For windows me and 9x we do not want to request more
1564 than it negotiated since it will refuse the read then */
1566 !(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
1567 current_read_size = min_t(const int, current_read_size,
1568 pTcon->ses->server->maxBuf - 128);
1571 while (rc == -EAGAIN) {
1572 if ((open_file->invalidHandle) &&
1573 (!open_file->closePend)) {
1574 rc = cifs_reopen_file(file->f_dentry->d_inode,
1579 rc = CIFSSMBRead(xid, pTcon,
1581 current_read_size, *poffset,
1582 &bytes_read, ¤t_offset,
1585 if (rc || (bytes_read == 0)) {
1593 cifs_stats_bytes_read(pTcon, total_read);
1594 *poffset += bytes_read;
1601 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
1603 struct dentry *dentry = file->f_dentry;
1607 rc = cifs_revalidate(dentry);
1609 cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
1613 rc = generic_file_mmap(file, vma);
1619 static void cifs_copy_cache_pages(struct address_space *mapping,
1620 struct list_head *pages, int bytes_read, char *data,
1621 struct pagevec *plru_pvec)
1626 while (bytes_read > 0) {
1627 if (list_empty(pages))
1630 page = list_entry(pages->prev, struct page, lru);
1631 list_del(&page->lru);
1633 if (add_to_page_cache(page, mapping, page->index,
1635 page_cache_release(page);
1636 cFYI(1, ("Add page cache failed"));
1637 data += PAGE_CACHE_SIZE;
1638 bytes_read -= PAGE_CACHE_SIZE;
1642 target = kmap_atomic(page,KM_USER0);
1644 if (PAGE_CACHE_SIZE > bytes_read) {
1645 memcpy(target, data, bytes_read);
1646 /* zero the tail end of this partial page */
1647 memset(target + bytes_read, 0,
1648 PAGE_CACHE_SIZE - bytes_read);
1651 memcpy(target, data, PAGE_CACHE_SIZE);
1652 bytes_read -= PAGE_CACHE_SIZE;
1654 kunmap_atomic(target, KM_USER0);
1656 flush_dcache_page(page);
1657 SetPageUptodate(page);
1659 if (!pagevec_add(plru_pvec, page))
1660 __pagevec_lru_add(plru_pvec);
1661 data += PAGE_CACHE_SIZE;
1666 static int cifs_readpages(struct file *file, struct address_space *mapping,
1667 struct list_head *page_list, unsigned num_pages)
1673 struct cifs_sb_info *cifs_sb;
1674 struct cifsTconInfo *pTcon;
1676 unsigned int read_size,i;
1677 char *smb_read_data = NULL;
1678 struct smb_com_read_rsp *pSMBr;
1679 struct pagevec lru_pvec;
1680 struct cifsFileInfo *open_file;
1681 int buf_type = CIFS_NO_BUFFER;
1684 if (file->private_data == NULL) {
1688 open_file = (struct cifsFileInfo *)file->private_data;
1689 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1690 pTcon = cifs_sb->tcon;
1692 pagevec_init(&lru_pvec, 0);
1694 for (i = 0; i < num_pages; ) {
1695 unsigned contig_pages;
1696 struct page *tmp_page;
1697 unsigned long expected_index;
1699 if (list_empty(page_list))
1702 page = list_entry(page_list->prev, struct page, lru);
1703 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1705 /* count adjacent pages that we will read into */
1708 list_entry(page_list->prev, struct page, lru)->index;
1709 list_for_each_entry_reverse(tmp_page,page_list,lru) {
1710 if (tmp_page->index == expected_index) {
1716 if (contig_pages + i > num_pages)
1717 contig_pages = num_pages - i;
1719 /* for reads over a certain size could initiate async
1722 read_size = contig_pages * PAGE_CACHE_SIZE;
1723 /* Read size needs to be in multiples of one page */
1724 read_size = min_t(const unsigned int, read_size,
1725 cifs_sb->rsize & PAGE_CACHE_MASK);
1728 while (rc == -EAGAIN) {
1729 if ((open_file->invalidHandle) &&
1730 (!open_file->closePend)) {
1731 rc = cifs_reopen_file(file->f_dentry->d_inode,
1737 rc = CIFSSMBRead(xid, pTcon,
1740 &bytes_read, &smb_read_data,
1742 /* BB more RC checks ? */
1744 if (smb_read_data) {
1745 if(buf_type == CIFS_SMALL_BUFFER)
1746 cifs_small_buf_release(smb_read_data);
1747 else if(buf_type == CIFS_LARGE_BUFFER)
1748 cifs_buf_release(smb_read_data);
1749 smb_read_data = NULL;
1753 if ((rc < 0) || (smb_read_data == NULL)) {
1754 cFYI(1, ("Read error in readpages: %d", rc));
1755 /* clean up remaing pages off list */
1756 while (!list_empty(page_list) && (i < num_pages)) {
1757 page = list_entry(page_list->prev, struct page,
1759 list_del(&page->lru);
1760 page_cache_release(page);
1763 } else if (bytes_read > 0) {
1764 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1765 cifs_copy_cache_pages(mapping, page_list, bytes_read,
1766 smb_read_data + 4 /* RFC1001 hdr */ +
1767 le16_to_cpu(pSMBr->DataOffset), &lru_pvec);
1769 i += bytes_read >> PAGE_CACHE_SHIFT;
1770 cifs_stats_bytes_read(pTcon, bytes_read);
1771 if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
1772 i++; /* account for partial page */
1774 /* server copy of file can have smaller size
1776 /* BB do we need to verify this common case ?
1777 this case is ok - if we are at server EOF
1778 we will hit it on next read */
1780 /* while (!list_empty(page_list) && (i < num_pages)) {
1781 page = list_entry(page_list->prev,
1783 list_del(&page->list);
1784 page_cache_release(page);
1789 cFYI(1, ("No bytes read (%d) at offset %lld . "
1790 "Cleaning remaining pages from readahead list",
1791 bytes_read, offset));
1792 /* BB turn off caching and do new lookup on
1793 file size at server? */
1794 while (!list_empty(page_list) && (i < num_pages)) {
1795 page = list_entry(page_list->prev, struct page,
1797 list_del(&page->lru);
1799 /* BB removeme - replace with zero of page? */
1800 page_cache_release(page);
1804 if (smb_read_data) {
1805 if(buf_type == CIFS_SMALL_BUFFER)
1806 cifs_small_buf_release(smb_read_data);
1807 else if(buf_type == CIFS_LARGE_BUFFER)
1808 cifs_buf_release(smb_read_data);
1809 smb_read_data = NULL;
1814 pagevec_lru_add(&lru_pvec);
1816 /* need to free smb_read_data buf before exit */
1817 if (smb_read_data) {
1818 if(buf_type == CIFS_SMALL_BUFFER)
1819 cifs_small_buf_release(smb_read_data);
1820 else if(buf_type == CIFS_LARGE_BUFFER)
1821 cifs_buf_release(smb_read_data);
1822 smb_read_data = NULL;
1829 static int cifs_readpage_worker(struct file *file, struct page *page,
1835 page_cache_get(page);
1836 read_data = kmap(page);
1837 /* for reads over a certain size could initiate async read ahead */
1839 rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
1844 cFYI(1, ("Bytes read %d",rc));
1846 file->f_dentry->d_inode->i_atime =
1847 current_fs_time(file->f_dentry->d_inode->i_sb);
1849 if (PAGE_CACHE_SIZE > rc)
1850 memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
1852 flush_dcache_page(page);
1853 SetPageUptodate(page);
1858 page_cache_release(page);
1862 static int cifs_readpage(struct file *file, struct page *page)
1864 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1870 if (file->private_data == NULL) {
1875 cFYI(1, ("readpage %p at offset %d 0x%x\n",
1876 page, (int)offset, (int)offset));
1878 rc = cifs_readpage_worker(file, page, &offset);
1886 /* We do not want to update the file size from server for inodes
1887 open for write - to avoid races with writepage extending
1888 the file - in the future we could consider allowing
1889 refreshing the inode only on increases in the file size
1890 but this is tricky to do without racing with writebehind
1891 page caching in the current Linux kernel design */
1892 int is_size_safe_to_change(struct cifsInodeInfo *cifsInode)
1894 struct cifsFileInfo *open_file = NULL;
1897 open_file = find_writable_file(cifsInode);
1900 struct cifs_sb_info *cifs_sb;
1902 /* there is not actually a write pending so let
1903 this handle go free and allow it to
1904 be closable if needed */
1905 atomic_dec(&open_file->wrtPending);
1907 cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
1908 if ( cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO ) {
1909 /* since no page cache to corrupt on directio
1910 we can change size safely */
1919 static int cifs_prepare_write(struct file *file, struct page *page,
1920 unsigned from, unsigned to)
1923 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1924 cFYI(1, ("prepare write for page %p from %d to %d",page,from,to));
1925 if (!PageUptodate(page)) {
1926 /* if (to - from != PAGE_CACHE_SIZE) {
1927 void *kaddr = kmap_atomic(page, KM_USER0);
1928 memset(kaddr, 0, from);
1929 memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
1930 flush_dcache_page(page);
1931 kunmap_atomic(kaddr, KM_USER0);
1933 /* If we are writing a full page it will be up to date,
1934 no need to read from the server */
1935 if ((to == PAGE_CACHE_SIZE) && (from == 0))
1936 SetPageUptodate(page);
1938 /* might as well read a page, it is fast enough */
1939 if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
1940 rc = cifs_readpage_worker(file, page, &offset);
1942 /* should we try using another file handle if there is one -
1943 how would we lock it to prevent close of that handle
1944 racing with this read?
1945 In any case this will be written out by commit_write */
1949 /* BB should we pass any errors back?
1950 e.g. if we do not have read access to the file */
1954 struct address_space_operations cifs_addr_ops = {
1955 .readpage = cifs_readpage,
1956 .readpages = cifs_readpages,
1957 .writepage = cifs_writepage,
1958 .writepages = cifs_writepages,
1959 .prepare_write = cifs_prepare_write,
1960 .commit_write = cifs_commit_write,
1961 .set_page_dirty = __set_page_dirty_nobuffers,
1962 /* .sync_page = cifs_sync_page, */
1967 * cifs_readpages requires the server to support a buffer large enough to
1968 * contain the header plus one complete page of data. Otherwise, we need
1969 * to leave cifs_readpages out of the address space operations.
1971 struct address_space_operations cifs_addr_ops_smallbuf = {
1972 .readpage = cifs_readpage,
1973 .writepage = cifs_writepage,
1974 .writepages = cifs_writepages,
1975 .prepare_write = cifs_prepare_write,
1976 .commit_write = cifs_commit_write,
1977 .set_page_dirty = __set_page_dirty_nobuffers,
1978 /* .sync_page = cifs_sync_page, */