4 * vfs operations that deal with files
6 * Copyright (C) International Business Machines Corp., 2002,2010
7 * Author(s): Steve French (sfrench@us.ibm.com)
8 * Jeremy Allison (jra@samba.org)
10 * This library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published
12 * by the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
18 * the GNU Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this library; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 #include <linux/backing-dev.h>
26 #include <linux/stat.h>
27 #include <linux/fcntl.h>
28 #include <linux/pagemap.h>
29 #include <linux/pagevec.h>
30 #include <linux/writeback.h>
31 #include <linux/task_io_accounting_ops.h>
32 #include <linux/delay.h>
33 #include <linux/mount.h>
34 #include <linux/slab.h>
35 #include <asm/div64.h>
39 #include "cifsproto.h"
40 #include "cifs_unicode.h"
41 #include "cifs_debug.h"
42 #include "cifs_fs_sb.h"
45 static inline int cifs_convert_flags(unsigned int flags)
47 if ((flags & O_ACCMODE) == O_RDONLY)
49 else if ((flags & O_ACCMODE) == O_WRONLY)
51 else if ((flags & O_ACCMODE) == O_RDWR) {
52 /* GENERIC_ALL is too much permission to request
53 can cause unnecessary access denied on create */
54 /* return GENERIC_ALL; */
55 return (GENERIC_READ | GENERIC_WRITE);
58 return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
59 FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
63 static u32 cifs_posix_convert_flags(unsigned int flags)
67 if ((flags & O_ACCMODE) == O_RDONLY)
68 posix_flags = SMB_O_RDONLY;
69 else if ((flags & O_ACCMODE) == O_WRONLY)
70 posix_flags = SMB_O_WRONLY;
71 else if ((flags & O_ACCMODE) == O_RDWR)
72 posix_flags = SMB_O_RDWR;
75 posix_flags |= SMB_O_CREAT;
77 posix_flags |= SMB_O_EXCL;
79 posix_flags |= SMB_O_TRUNC;
80 /* be safe and imply O_SYNC for O_DSYNC */
82 posix_flags |= SMB_O_SYNC;
83 if (flags & O_DIRECTORY)
84 posix_flags |= SMB_O_DIRECTORY;
85 if (flags & O_NOFOLLOW)
86 posix_flags |= SMB_O_NOFOLLOW;
88 posix_flags |= SMB_O_DIRECT;
93 static inline int cifs_get_disposition(unsigned int flags)
95 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
97 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
98 return FILE_OVERWRITE_IF;
99 else if ((flags & O_CREAT) == O_CREAT)
101 else if ((flags & O_TRUNC) == O_TRUNC)
102 return FILE_OVERWRITE;
107 int cifs_posix_open(char *full_path, struct inode **pinode,
108 struct super_block *sb, int mode, unsigned int f_flags,
109 __u32 *poplock, __u16 *pnetfid, int xid)
112 FILE_UNIX_BASIC_INFO *presp_data;
113 __u32 posix_flags = 0;
114 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
115 struct cifs_fattr fattr;
116 struct tcon_link *tlink;
117 struct cifsTconInfo *tcon;
119 cFYI(1, "posix open %s", full_path);
121 presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
122 if (presp_data == NULL)
125 tlink = cifs_sb_tlink(cifs_sb);
131 tcon = tlink_tcon(tlink);
132 mode &= ~current_umask();
134 posix_flags = cifs_posix_convert_flags(f_flags);
135 rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
136 poplock, full_path, cifs_sb->local_nls,
137 cifs_sb->mnt_cifs_flags &
138 CIFS_MOUNT_MAP_SPECIAL_CHR);
139 cifs_put_tlink(tlink);
144 if (presp_data->Type == cpu_to_le32(-1))
145 goto posix_open_ret; /* open ok, caller does qpathinfo */
148 goto posix_open_ret; /* caller does not need info */
150 cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
152 /* get new inode and set it up */
153 if (*pinode == NULL) {
154 cifs_fill_uniqueid(sb, &fattr);
155 *pinode = cifs_iget(sb, &fattr);
161 cifs_fattr_to_inode(*pinode, &fattr);
170 cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
171 struct cifsTconInfo *tcon, unsigned int f_flags, __u32 *poplock,
172 __u16 *pnetfid, int xid)
179 desiredAccess = cifs_convert_flags(f_flags);
181 /*********************************************************************
182 * open flag mapping table:
184 * POSIX Flag CIFS Disposition
185 * ---------- ----------------
186 * O_CREAT FILE_OPEN_IF
187 * O_CREAT | O_EXCL FILE_CREATE
188 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
189 * O_TRUNC FILE_OVERWRITE
190 * none of the above FILE_OPEN
192 * Note that there is not a direct match between disposition
193 * FILE_SUPERSEDE (ie create whether or not file exists although
194 * O_CREAT | O_TRUNC is similar but truncates the existing
195 * file rather than creating a new file as FILE_SUPERSEDE does
196 * (which uses the attributes / metadata passed in on open call)
198 *? O_SYNC is a reasonable match to CIFS writethrough flag
199 *? and the read write flags match reasonably. O_LARGEFILE
200 *? is irrelevant because largefile support is always used
201 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
202 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
203 *********************************************************************/
205 disposition = cifs_get_disposition(f_flags);
207 /* BB pass O_SYNC flag through on file attributes .. BB */
209 buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
213 if (tcon->ses->capabilities & CAP_NT_SMBS)
214 rc = CIFSSMBOpen(xid, tcon, full_path, disposition,
215 desiredAccess, CREATE_NOT_DIR, pnetfid, poplock, buf,
216 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
217 & CIFS_MOUNT_MAP_SPECIAL_CHR);
219 rc = SMBLegacyOpen(xid, tcon, full_path, disposition,
220 desiredAccess, CREATE_NOT_DIR, pnetfid, poplock, buf,
221 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
222 & CIFS_MOUNT_MAP_SPECIAL_CHR);
228 rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
231 rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
239 struct cifsFileInfo *
240 cifs_new_fileinfo(__u16 fileHandle, struct file *file,
241 struct tcon_link *tlink, __u32 oplock)
243 struct dentry *dentry = file->f_path.dentry;
244 struct inode *inode = dentry->d_inode;
245 struct cifsInodeInfo *pCifsInode = CIFS_I(inode);
246 struct cifsFileInfo *pCifsFile;
248 pCifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
249 if (pCifsFile == NULL)
252 pCifsFile->count = 1;
253 pCifsFile->netfid = fileHandle;
254 pCifsFile->pid = current->tgid;
255 pCifsFile->uid = current_fsuid();
256 pCifsFile->dentry = dget(dentry);
257 pCifsFile->f_flags = file->f_flags;
258 pCifsFile->invalidHandle = false;
259 pCifsFile->tlink = cifs_get_tlink(tlink);
260 mutex_init(&pCifsFile->fh_mutex);
261 mutex_init(&pCifsFile->lock_mutex);
262 INIT_LIST_HEAD(&pCifsFile->llist);
263 INIT_WORK(&pCifsFile->oplock_break, cifs_oplock_break);
265 spin_lock(&cifs_file_list_lock);
266 list_add(&pCifsFile->tlist, &(tlink_tcon(tlink)->openFileList));
267 /* if readable file instance put first in list*/
268 if (file->f_mode & FMODE_READ)
269 list_add(&pCifsFile->flist, &pCifsInode->openFileList);
271 list_add_tail(&pCifsFile->flist, &pCifsInode->openFileList);
272 spin_unlock(&cifs_file_list_lock);
274 cifs_set_oplock_level(pCifsInode, oplock);
276 file->private_data = pCifsFile;
281 * Release a reference on the file private data. This may involve closing
282 * the filehandle out on the server. Must be called without holding
283 * cifs_file_list_lock.
285 void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
287 struct inode *inode = cifs_file->dentry->d_inode;
288 struct cifsTconInfo *tcon = tlink_tcon(cifs_file->tlink);
289 struct cifsInodeInfo *cifsi = CIFS_I(inode);
290 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
291 struct cifsLockInfo *li, *tmp;
293 spin_lock(&cifs_file_list_lock);
294 if (--cifs_file->count > 0) {
295 spin_unlock(&cifs_file_list_lock);
299 /* remove it from the lists */
300 list_del(&cifs_file->flist);
301 list_del(&cifs_file->tlist);
303 if (list_empty(&cifsi->openFileList)) {
304 cFYI(1, "closing last open instance for inode %p",
305 cifs_file->dentry->d_inode);
307 /* in strict cache mode we need invalidate mapping on the last
308 close because it may cause a error when we open this file
309 again and get at least level II oplock */
310 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
311 CIFS_I(inode)->invalid_mapping = true;
313 cifs_set_oplock_level(cifsi, 0);
315 spin_unlock(&cifs_file_list_lock);
317 if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
321 rc = CIFSSMBClose(xid, tcon, cifs_file->netfid);
325 /* Delete any outstanding lock records. We'll lose them when the file
328 mutex_lock(&cifs_file->lock_mutex);
329 list_for_each_entry_safe(li, tmp, &cifs_file->llist, llist) {
330 list_del(&li->llist);
333 mutex_unlock(&cifs_file->lock_mutex);
335 cifs_put_tlink(cifs_file->tlink);
336 dput(cifs_file->dentry);
340 int cifs_open(struct inode *inode, struct file *file)
345 struct cifs_sb_info *cifs_sb;
346 struct cifsTconInfo *tcon;
347 struct tcon_link *tlink;
348 struct cifsFileInfo *pCifsFile = NULL;
349 struct cifsInodeInfo *pCifsInode;
350 char *full_path = NULL;
351 bool posix_open_ok = false;
356 cifs_sb = CIFS_SB(inode->i_sb);
357 tlink = cifs_sb_tlink(cifs_sb);
360 return PTR_ERR(tlink);
362 tcon = tlink_tcon(tlink);
364 pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
366 full_path = build_path_from_dentry(file->f_path.dentry);
367 if (full_path == NULL) {
372 cFYI(1, "inode = 0x%p file flags are 0x%x for %s",
373 inode, file->f_flags, full_path);
380 if (!tcon->broken_posix_open && tcon->unix_ext &&
381 (tcon->ses->capabilities & CAP_UNIX) &&
382 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
383 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
384 /* can not refresh inode info since size could be stale */
385 rc = cifs_posix_open(full_path, &inode, inode->i_sb,
386 cifs_sb->mnt_file_mode /* ignored */,
387 file->f_flags, &oplock, &netfid, xid);
389 cFYI(1, "posix open succeeded");
390 posix_open_ok = true;
391 } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
392 if (tcon->ses->serverNOS)
393 cERROR(1, "server %s of type %s returned"
394 " unexpected error on SMB posix open"
395 ", disabling posix open support."
396 " Check if server update available.",
397 tcon->ses->serverName,
398 tcon->ses->serverNOS);
399 tcon->broken_posix_open = true;
400 } else if ((rc != -EIO) && (rc != -EREMOTE) &&
401 (rc != -EOPNOTSUPP)) /* path not found or net err */
403 /* else fallthrough to retry open the old way on network i/o
407 if (!posix_open_ok) {
408 rc = cifs_nt_open(full_path, inode, cifs_sb, tcon,
409 file->f_flags, &oplock, &netfid, xid);
414 pCifsFile = cifs_new_fileinfo(netfid, file, tlink, oplock);
415 if (pCifsFile == NULL) {
416 CIFSSMBClose(xid, tcon, netfid);
421 cifs_fscache_set_inode_cookie(inode, file);
423 if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
424 /* time to set mode which we can not set earlier due to
425 problems creating new read-only files */
426 struct cifs_unix_set_info_args args = {
427 .mode = inode->i_mode,
430 .ctime = NO_CHANGE_64,
431 .atime = NO_CHANGE_64,
432 .mtime = NO_CHANGE_64,
435 CIFSSMBUnixSetFileInfo(xid, tcon, &args, netfid,
442 cifs_put_tlink(tlink);
446 /* Try to reacquire byte range locks that were released when session */
447 /* to server was lost */
448 static int cifs_relock_file(struct cifsFileInfo *cifsFile)
452 /* BB list all locks open on this file and relock */
457 static int cifs_reopen_file(struct cifsFileInfo *pCifsFile, bool can_flush)
462 struct cifs_sb_info *cifs_sb;
463 struct cifsTconInfo *tcon;
464 struct cifsInodeInfo *pCifsInode;
466 char *full_path = NULL;
468 int disposition = FILE_OPEN;
472 mutex_lock(&pCifsFile->fh_mutex);
473 if (!pCifsFile->invalidHandle) {
474 mutex_unlock(&pCifsFile->fh_mutex);
480 inode = pCifsFile->dentry->d_inode;
481 cifs_sb = CIFS_SB(inode->i_sb);
482 tcon = tlink_tcon(pCifsFile->tlink);
484 /* can not grab rename sem here because various ops, including
485 those that already have the rename sem can end up causing writepage
486 to get called and if the server was down that means we end up here,
487 and we can never tell if the caller already has the rename_sem */
488 full_path = build_path_from_dentry(pCifsFile->dentry);
489 if (full_path == NULL) {
491 mutex_unlock(&pCifsFile->fh_mutex);
496 cFYI(1, "inode = 0x%p file flags 0x%x for %s",
497 inode, pCifsFile->f_flags, full_path);
504 if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
505 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
506 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
509 * O_CREAT, O_EXCL and O_TRUNC already had their effect on the
510 * original open. Must mask them off for a reopen.
512 unsigned int oflags = pCifsFile->f_flags &
513 ~(O_CREAT | O_EXCL | O_TRUNC);
515 rc = cifs_posix_open(full_path, NULL, inode->i_sb,
516 cifs_sb->mnt_file_mode /* ignored */,
517 oflags, &oplock, &netfid, xid);
519 cFYI(1, "posix reopen succeeded");
522 /* fallthrough to retry open the old way on errors, especially
523 in the reconnect path it is important to retry hard */
526 desiredAccess = cifs_convert_flags(pCifsFile->f_flags);
528 /* Can not refresh inode by passing in file_info buf to be returned
529 by SMBOpen and then calling get_inode_info with returned buf
530 since file might have write behind data that needs to be flushed
531 and server version of file size can be stale. If we knew for sure
532 that inode was not dirty locally we could do this */
534 rc = CIFSSMBOpen(xid, tcon, full_path, disposition, desiredAccess,
535 CREATE_NOT_DIR, &netfid, &oplock, NULL,
536 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
537 CIFS_MOUNT_MAP_SPECIAL_CHR);
539 mutex_unlock(&pCifsFile->fh_mutex);
540 cFYI(1, "cifs_open returned 0x%x", rc);
541 cFYI(1, "oplock: %d", oplock);
542 goto reopen_error_exit;
546 pCifsFile->netfid = netfid;
547 pCifsFile->invalidHandle = false;
548 mutex_unlock(&pCifsFile->fh_mutex);
549 pCifsInode = CIFS_I(inode);
552 rc = filemap_write_and_wait(inode->i_mapping);
553 mapping_set_error(inode->i_mapping, rc);
556 rc = cifs_get_inode_info_unix(&inode,
557 full_path, inode->i_sb, xid);
559 rc = cifs_get_inode_info(&inode,
560 full_path, NULL, inode->i_sb,
562 } /* else we are writing out data to server already
563 and could deadlock if we tried to flush data, and
564 since we do not know if we have data that would
565 invalidate the current end of file on the server
566 we can not go to the server to get the new inod
569 cifs_set_oplock_level(pCifsInode, oplock);
571 cifs_relock_file(pCifsFile);
579 int cifs_close(struct inode *inode, struct file *file)
581 cifsFileInfo_put(file->private_data);
582 file->private_data = NULL;
584 /* return code from the ->release op is always ignored */
588 int cifs_closedir(struct inode *inode, struct file *file)
592 struct cifsFileInfo *pCFileStruct = file->private_data;
595 cFYI(1, "Closedir inode = 0x%p", inode);
600 struct cifsTconInfo *pTcon = tlink_tcon(pCFileStruct->tlink);
602 cFYI(1, "Freeing private data in close dir");
603 spin_lock(&cifs_file_list_lock);
604 if (!pCFileStruct->srch_inf.endOfSearch &&
605 !pCFileStruct->invalidHandle) {
606 pCFileStruct->invalidHandle = true;
607 spin_unlock(&cifs_file_list_lock);
608 rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
609 cFYI(1, "Closing uncompleted readdir with rc %d",
611 /* not much we can do if it fails anyway, ignore rc */
614 spin_unlock(&cifs_file_list_lock);
615 ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
617 cFYI(1, "closedir free smb buf in srch struct");
618 pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
619 if (pCFileStruct->srch_inf.smallBuf)
620 cifs_small_buf_release(ptmp);
622 cifs_buf_release(ptmp);
624 cifs_put_tlink(pCFileStruct->tlink);
625 kfree(file->private_data);
626 file->private_data = NULL;
628 /* BB can we lock the filestruct while this is going on? */
633 static int store_file_lock(struct cifsFileInfo *fid, __u64 len,
634 __u64 offset, __u8 lockType)
636 struct cifsLockInfo *li =
637 kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
643 mutex_lock(&fid->lock_mutex);
644 list_add(&li->llist, &fid->llist);
645 mutex_unlock(&fid->lock_mutex);
649 int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
655 bool wait_flag = false;
656 struct cifs_sb_info *cifs_sb;
657 struct cifsTconInfo *tcon;
659 __u8 lockType = LOCKING_ANDX_LARGE_FILES;
660 bool posix_locking = 0;
662 length = 1 + pfLock->fl_end - pfLock->fl_start;
666 cFYI(1, "Lock parm: 0x%x flockflags: "
667 "0x%x flocktype: 0x%x start: %lld end: %lld",
668 cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
671 if (pfLock->fl_flags & FL_POSIX)
673 if (pfLock->fl_flags & FL_FLOCK)
675 if (pfLock->fl_flags & FL_SLEEP) {
676 cFYI(1, "Blocking lock");
679 if (pfLock->fl_flags & FL_ACCESS)
680 cFYI(1, "Process suspended by mandatory locking - "
681 "not implemented yet");
682 if (pfLock->fl_flags & FL_LEASE)
683 cFYI(1, "Lease on file - not implemented yet");
684 if (pfLock->fl_flags &
685 (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
686 cFYI(1, "Unknown lock flags 0x%x", pfLock->fl_flags);
688 if (pfLock->fl_type == F_WRLCK) {
691 } else if (pfLock->fl_type == F_UNLCK) {
694 /* Check if unlock includes more than
696 } else if (pfLock->fl_type == F_RDLCK) {
698 lockType |= LOCKING_ANDX_SHARED_LOCK;
700 } else if (pfLock->fl_type == F_EXLCK) {
703 } else if (pfLock->fl_type == F_SHLCK) {
705 lockType |= LOCKING_ANDX_SHARED_LOCK;
708 cFYI(1, "Unknown type of lock");
710 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
711 tcon = tlink_tcon(((struct cifsFileInfo *)file->private_data)->tlink);
712 netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
714 if ((tcon->ses->capabilities & CAP_UNIX) &&
715 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
716 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
718 /* BB add code here to normalize offset and length to
719 account for negative length which we can not accept over the
724 if (lockType & LOCKING_ANDX_SHARED_LOCK)
725 posix_lock_type = CIFS_RDLCK;
727 posix_lock_type = CIFS_WRLCK;
728 rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,
730 posix_lock_type, wait_flag);
735 /* BB we could chain these into one lock request BB */
736 rc = CIFSSMBLock(xid, tcon, netfid, length, pfLock->fl_start,
737 0, 1, lockType, 0 /* wait flag */, 0);
739 rc = CIFSSMBLock(xid, tcon, netfid, length,
740 pfLock->fl_start, 1 /* numUnlock */ ,
741 0 /* numLock */ , lockType,
742 0 /* wait flag */, 0);
743 pfLock->fl_type = F_UNLCK;
745 cERROR(1, "Error unlocking previously locked "
746 "range %d during test of lock", rc);
750 /* if rc == ERR_SHARING_VIOLATION ? */
753 if (lockType & LOCKING_ANDX_SHARED_LOCK) {
754 pfLock->fl_type = F_WRLCK;
756 rc = CIFSSMBLock(xid, tcon, netfid, length,
757 pfLock->fl_start, 0, 1,
758 lockType | LOCKING_ANDX_SHARED_LOCK,
759 0 /* wait flag */, 0);
761 rc = CIFSSMBLock(xid, tcon, netfid,
762 length, pfLock->fl_start, 1, 0,
764 LOCKING_ANDX_SHARED_LOCK,
765 0 /* wait flag */, 0);
766 pfLock->fl_type = F_RDLCK;
768 cERROR(1, "Error unlocking "
769 "previously locked range %d "
770 "during test of lock", rc);
773 pfLock->fl_type = F_WRLCK;
783 if (!numLock && !numUnlock) {
784 /* if no lock or unlock then nothing
785 to do since we do not know what it is */
792 if (lockType & LOCKING_ANDX_SHARED_LOCK)
793 posix_lock_type = CIFS_RDLCK;
795 posix_lock_type = CIFS_WRLCK;
798 posix_lock_type = CIFS_UNLCK;
800 rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */,
802 posix_lock_type, wait_flag);
804 struct cifsFileInfo *fid = file->private_data;
807 rc = CIFSSMBLock(xid, tcon, netfid, length,
808 pfLock->fl_start, 0, numLock, lockType,
812 /* For Windows locks we must store them. */
813 rc = store_file_lock(fid, length,
814 pfLock->fl_start, lockType);
816 } else if (numUnlock) {
817 /* For each stored lock that this unlock overlaps
818 completely, unlock it. */
820 struct cifsLockInfo *li, *tmp;
823 mutex_lock(&fid->lock_mutex);
824 list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
825 if (pfLock->fl_start <= li->offset &&
826 (pfLock->fl_start + length) >=
827 (li->offset + li->length)) {
828 stored_rc = CIFSSMBLock(xid, tcon,
835 list_del(&li->llist);
840 mutex_unlock(&fid->lock_mutex);
844 if (pfLock->fl_flags & FL_POSIX)
845 posix_lock_file_wait(file, pfLock);
850 /* update the file size (if needed) after a write */
852 cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
853 unsigned int bytes_written)
855 loff_t end_of_write = offset + bytes_written;
857 if (end_of_write > cifsi->server_eof)
858 cifsi->server_eof = end_of_write;
861 ssize_t cifs_user_write(struct file *file, const char __user *write_data,
862 size_t write_size, loff_t *poffset)
864 struct inode *inode = file->f_path.dentry->d_inode;
866 unsigned int bytes_written = 0;
867 unsigned int total_written;
868 struct cifs_sb_info *cifs_sb;
869 struct cifsTconInfo *pTcon;
871 struct cifsFileInfo *open_file;
872 struct cifsInodeInfo *cifsi = CIFS_I(inode);
874 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
876 /* cFYI(1, " write %d bytes to offset %lld of %s", write_size,
877 *poffset, file->f_path.dentry->d_name.name); */
879 if (file->private_data == NULL)
882 open_file = file->private_data;
883 pTcon = tlink_tcon(open_file->tlink);
885 rc = generic_write_checks(file, poffset, &write_size, 0);
891 for (total_written = 0; write_size > total_written;
892 total_written += bytes_written) {
894 while (rc == -EAGAIN) {
895 if (file->private_data == NULL) {
896 /* file has been closed on us */
898 /* if we have gotten here we have written some data
899 and blocked, and the file has been freed on us while
900 we blocked so return what we managed to write */
901 return total_written;
903 if (open_file->invalidHandle) {
904 /* we could deadlock if we called
905 filemap_fdatawait from here so tell
906 reopen_file not to flush data to server
908 rc = cifs_reopen_file(open_file, false);
913 rc = CIFSSMBWrite(xid, pTcon,
915 min_t(const int, cifs_sb->wsize,
916 write_size - total_written),
917 *poffset, &bytes_written,
918 NULL, write_data + total_written, 0);
920 if (rc || (bytes_written == 0)) {
928 cifs_update_eof(cifsi, *poffset, bytes_written);
929 *poffset += bytes_written;
933 cifs_stats_bytes_written(pTcon, total_written);
935 /* Do not update local mtime - server will set its actual value on write
936 * inode->i_ctime = inode->i_mtime =
937 * current_fs_time(inode->i_sb);*/
938 if (total_written > 0) {
939 spin_lock(&inode->i_lock);
940 if (*poffset > inode->i_size)
941 i_size_write(inode, *poffset);
942 spin_unlock(&inode->i_lock);
944 mark_inode_dirty_sync(inode);
947 return total_written;
950 static ssize_t cifs_write(struct cifsFileInfo *open_file,
951 const char *write_data, size_t write_size,
955 unsigned int bytes_written = 0;
956 unsigned int total_written;
957 struct cifs_sb_info *cifs_sb;
958 struct cifsTconInfo *pTcon;
960 struct dentry *dentry = open_file->dentry;
961 struct cifsInodeInfo *cifsi = CIFS_I(dentry->d_inode);
963 cifs_sb = CIFS_SB(dentry->d_sb);
965 cFYI(1, "write %zd bytes to offset %lld of %s", write_size,
966 *poffset, dentry->d_name.name);
968 pTcon = tlink_tcon(open_file->tlink);
972 for (total_written = 0; write_size > total_written;
973 total_written += bytes_written) {
975 while (rc == -EAGAIN) {
976 if (open_file->invalidHandle) {
977 /* we could deadlock if we called
978 filemap_fdatawait from here so tell
979 reopen_file not to flush data to
981 rc = cifs_reopen_file(open_file, false);
985 if (experimEnabled || (pTcon->ses->server &&
986 ((pTcon->ses->server->secMode &
987 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
992 len = min((size_t)cifs_sb->wsize,
993 write_size - total_written);
994 /* iov[0] is reserved for smb header */
995 iov[1].iov_base = (char *)write_data +
997 iov[1].iov_len = len;
998 rc = CIFSSMBWrite2(xid, pTcon,
999 open_file->netfid, len,
1000 *poffset, &bytes_written,
1003 rc = CIFSSMBWrite(xid, pTcon,
1005 min_t(const int, cifs_sb->wsize,
1006 write_size - total_written),
1007 *poffset, &bytes_written,
1008 write_data + total_written,
1011 if (rc || (bytes_written == 0)) {
1019 cifs_update_eof(cifsi, *poffset, bytes_written);
1020 *poffset += bytes_written;
1024 cifs_stats_bytes_written(pTcon, total_written);
1026 if (total_written > 0) {
1027 spin_lock(&dentry->d_inode->i_lock);
1028 if (*poffset > dentry->d_inode->i_size)
1029 i_size_write(dentry->d_inode, *poffset);
1030 spin_unlock(&dentry->d_inode->i_lock);
1032 mark_inode_dirty_sync(dentry->d_inode);
1034 return total_written;
1037 struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
1040 struct cifsFileInfo *open_file = NULL;
1041 struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
1043 /* only filter by fsuid on multiuser mounts */
1044 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
1047 spin_lock(&cifs_file_list_lock);
1048 /* we could simply get the first_list_entry since write-only entries
1049 are always at the end of the list but since the first entry might
1050 have a close pending, we go through the whole list */
1051 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1052 if (fsuid_only && open_file->uid != current_fsuid())
1054 if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
1055 if (!open_file->invalidHandle) {
1056 /* found a good file */
1057 /* lock it so it will not be closed on us */
1058 cifsFileInfo_get(open_file);
1059 spin_unlock(&cifs_file_list_lock);
1061 } /* else might as well continue, and look for
1062 another, or simply have the caller reopen it
1063 again rather than trying to fix this handle */
1064 } else /* write only file */
1065 break; /* write only files are last so must be done */
1067 spin_unlock(&cifs_file_list_lock);
1071 struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
1074 struct cifsFileInfo *open_file;
1075 struct cifs_sb_info *cifs_sb;
1076 bool any_available = false;
1079 /* Having a null inode here (because mapping->host was set to zero by
1080 the VFS or MM) should not happen but we had reports of on oops (due to
1081 it being zero) during stress testcases so we need to check for it */
1083 if (cifs_inode == NULL) {
1084 cERROR(1, "Null inode passed to cifs_writeable_file");
1089 cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
1091 /* only filter by fsuid on multiuser mounts */
1092 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
1095 spin_lock(&cifs_file_list_lock);
1097 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1098 if (!any_available && open_file->pid != current->tgid)
1100 if (fsuid_only && open_file->uid != current_fsuid())
1102 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
1103 cifsFileInfo_get(open_file);
1105 if (!open_file->invalidHandle) {
1106 /* found a good writable file */
1107 spin_unlock(&cifs_file_list_lock);
1111 spin_unlock(&cifs_file_list_lock);
1113 /* Had to unlock since following call can block */
1114 rc = cifs_reopen_file(open_file, false);
1118 /* if it fails, try another handle if possible */
1119 cFYI(1, "wp failed on reopen file");
1120 cifsFileInfo_put(open_file);
1122 spin_lock(&cifs_file_list_lock);
1124 /* else we simply continue to the next entry. Thus
1125 we do not loop on reopen errors. If we
1126 can not reopen the file, for example if we
1127 reconnected to a server with another client
1128 racing to delete or lock the file we would not
1129 make progress if we restarted before the beginning
1130 of the loop here. */
1133 /* couldn't find useable FH with same pid, try any available */
1134 if (!any_available) {
1135 any_available = true;
1136 goto refind_writable;
1138 spin_unlock(&cifs_file_list_lock);
1142 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
1144 struct address_space *mapping = page->mapping;
1145 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1148 int bytes_written = 0;
1149 struct cifs_sb_info *cifs_sb;
1150 struct inode *inode;
1151 struct cifsFileInfo *open_file;
1153 if (!mapping || !mapping->host)
1156 inode = page->mapping->host;
1157 cifs_sb = CIFS_SB(inode->i_sb);
1159 offset += (loff_t)from;
1160 write_data = kmap(page);
1163 if ((to > PAGE_CACHE_SIZE) || (from > to)) {
1168 /* racing with truncate? */
1169 if (offset > mapping->host->i_size) {
1171 return 0; /* don't care */
1174 /* check to make sure that we are not extending the file */
1175 if (mapping->host->i_size - offset < (loff_t)to)
1176 to = (unsigned)(mapping->host->i_size - offset);
1178 open_file = find_writable_file(CIFS_I(mapping->host), false);
1180 bytes_written = cifs_write(open_file, write_data,
1181 to - from, &offset);
1182 cifsFileInfo_put(open_file);
1183 /* Does mm or vfs already set times? */
1184 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1185 if ((bytes_written > 0) && (offset))
1187 else if (bytes_written < 0)
1190 cFYI(1, "No writeable filehandles for inode");
1198 static int cifs_writepages(struct address_space *mapping,
1199 struct writeback_control *wbc)
1201 unsigned int bytes_to_write;
1202 unsigned int bytes_written;
1203 struct cifs_sb_info *cifs_sb;
1207 int range_whole = 0;
1214 struct cifsFileInfo *open_file;
1215 struct cifsTconInfo *tcon;
1216 struct cifsInodeInfo *cifsi = CIFS_I(mapping->host);
1218 struct pagevec pvec;
1223 cifs_sb = CIFS_SB(mapping->host->i_sb);
1226 * If wsize is smaller that the page cache size, default to writing
1227 * one page at a time via cifs_writepage
1229 if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1230 return generic_writepages(mapping, wbc);
1232 iov = kmalloc(32 * sizeof(struct kvec), GFP_KERNEL);
1234 return generic_writepages(mapping, wbc);
1237 * if there's no open file, then this is likely to fail too,
1238 * but it'll at least handle the return. Maybe it should be
1241 open_file = find_writable_file(CIFS_I(mapping->host), false);
1244 return generic_writepages(mapping, wbc);
1247 tcon = tlink_tcon(open_file->tlink);
1248 if (!experimEnabled && tcon->ses->server->secMode &
1249 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
1250 cifsFileInfo_put(open_file);
1252 return generic_writepages(mapping, wbc);
1254 cifsFileInfo_put(open_file);
1258 pagevec_init(&pvec, 0);
1259 if (wbc->range_cyclic) {
1260 index = mapping->writeback_index; /* Start from prev offset */
1263 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1264 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1265 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1270 while (!done && (index <= end) &&
1271 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
1272 PAGECACHE_TAG_DIRTY,
1273 min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
1282 for (i = 0; i < nr_pages; i++) {
1283 page = pvec.pages[i];
1285 * At this point we hold neither mapping->tree_lock nor
1286 * lock on the page itself: the page may be truncated or
1287 * invalidated (changing page->mapping to NULL), or even
1288 * swizzled back from swapper_space to tmpfs file
1294 else if (!trylock_page(page))
1297 if (unlikely(page->mapping != mapping)) {
1302 if (!wbc->range_cyclic && page->index > end) {
1308 if (next && (page->index != next)) {
1309 /* Not next consecutive page */
1314 if (wbc->sync_mode != WB_SYNC_NONE)
1315 wait_on_page_writeback(page);
1317 if (PageWriteback(page) ||
1318 !clear_page_dirty_for_io(page)) {
1324 * This actually clears the dirty bit in the radix tree.
1325 * See cifs_writepage() for more commentary.
1327 set_page_writeback(page);
1329 if (page_offset(page) >= mapping->host->i_size) {
1332 end_page_writeback(page);
1337 * BB can we get rid of this? pages are held by pvec
1339 page_cache_get(page);
1341 len = min(mapping->host->i_size - page_offset(page),
1342 (loff_t)PAGE_CACHE_SIZE);
1344 /* reserve iov[0] for the smb header */
1346 iov[n_iov].iov_base = kmap(page);
1347 iov[n_iov].iov_len = len;
1348 bytes_to_write += len;
1352 offset = page_offset(page);
1354 next = page->index + 1;
1355 if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
1360 open_file = find_writable_file(CIFS_I(mapping->host),
1363 cERROR(1, "No writable handles for inode");
1366 rc = CIFSSMBWrite2(xid, tcon, open_file->netfid,
1367 bytes_to_write, offset,
1368 &bytes_written, iov, n_iov,
1370 cifsFileInfo_put(open_file);
1373 cFYI(1, "Write2 rc=%d, wrote=%u", rc, bytes_written);
1376 * For now, treat a short write as if nothing got
1377 * written. A zero length write however indicates
1378 * ENOSPC or EFBIG. We have no way to know which
1379 * though, so call it ENOSPC for now. EFBIG would
1380 * get translated to AS_EIO anyway.
1382 * FIXME: make it take into account the data that did
1386 if (bytes_written == 0)
1388 else if (bytes_written < bytes_to_write)
1392 /* retry on data-integrity flush */
1393 if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN)
1396 /* fix the stats and EOF */
1397 if (bytes_written > 0) {
1398 cifs_stats_bytes_written(tcon, bytes_written);
1399 cifs_update_eof(cifsi, offset, bytes_written);
1402 for (i = 0; i < n_iov; i++) {
1403 page = pvec.pages[first + i];
1404 /* on retryable write error, redirty page */
1406 redirty_page_for_writepage(wbc, page);
1411 end_page_writeback(page);
1412 page_cache_release(page);
1416 mapping_set_error(mapping, rc);
1420 if ((wbc->nr_to_write -= n_iov) <= 0)
1424 /* Need to re-find the pages we skipped */
1425 index = pvec.pages[0]->index + 1;
1427 pagevec_release(&pvec);
1429 if (!scanned && !done) {
1431 * We hit the last page and there is more work to be done: wrap
1432 * back to the start of the file
1438 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1439 mapping->writeback_index = index;
1446 static int cifs_writepage(struct page *page, struct writeback_control *wbc)
1452 /* BB add check for wbc flags */
1453 page_cache_get(page);
1454 if (!PageUptodate(page))
1455 cFYI(1, "ppw - page not up to date");
1458 * Set the "writeback" flag, and clear "dirty" in the radix tree.
1460 * A writepage() implementation always needs to do either this,
1461 * or re-dirty the page with "redirty_page_for_writepage()" in
1462 * the case of a failure.
1464 * Just unlocking the page will cause the radix tree tag-bits
1465 * to fail to update with the state of the page correctly.
1467 set_page_writeback(page);
1468 rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1469 SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
1471 end_page_writeback(page);
1472 page_cache_release(page);
1477 static int cifs_write_end(struct file *file, struct address_space *mapping,
1478 loff_t pos, unsigned len, unsigned copied,
1479 struct page *page, void *fsdata)
1482 struct inode *inode = mapping->host;
1484 cFYI(1, "write_end for page %p from pos %lld with %d bytes",
1487 if (PageChecked(page)) {
1489 SetPageUptodate(page);
1490 ClearPageChecked(page);
1491 } else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
1492 SetPageUptodate(page);
1494 if (!PageUptodate(page)) {
1496 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
1500 /* this is probably better than directly calling
1501 partialpage_write since in this function the file handle is
1502 known which we might as well leverage */
1503 /* BB check if anything else missing out of ppw
1504 such as updating last write time */
1505 page_data = kmap(page);
1506 rc = cifs_write(file->private_data, page_data + offset,
1508 /* if (rc < 0) should we set writebehind rc? */
1515 set_page_dirty(page);
1519 spin_lock(&inode->i_lock);
1520 if (pos > inode->i_size)
1521 i_size_write(inode, pos);
1522 spin_unlock(&inode->i_lock);
1526 page_cache_release(page);
1531 int cifs_fsync(struct file *file, int datasync)
1535 struct cifsTconInfo *tcon;
1536 struct cifsFileInfo *smbfile = file->private_data;
1537 struct inode *inode = file->f_path.dentry->d_inode;
1541 cFYI(1, "Sync file - name: %s datasync: 0x%x",
1542 file->f_path.dentry->d_name.name, datasync);
1544 rc = filemap_write_and_wait(inode->i_mapping);
1546 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
1548 tcon = tlink_tcon(smbfile->tlink);
1549 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
1550 rc = CIFSSMBFlush(xid, tcon, smbfile->netfid);
1557 /* static void cifs_sync_page(struct page *page)
1559 struct address_space *mapping;
1560 struct inode *inode;
1561 unsigned long index = page->index;
1562 unsigned int rpages = 0;
1565 cFYI(1, "sync page %p", page);
1566 mapping = page->mapping;
1569 inode = mapping->host;
1573 /* fill in rpages then
1574 result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
1576 /* cFYI(1, "rpages is %d for sync page of Index %ld", rpages, index);
1586 * As file closes, flush all cached write data for this inode checking
1587 * for write behind errors.
1589 int cifs_flush(struct file *file, fl_owner_t id)
1591 struct inode *inode = file->f_path.dentry->d_inode;
1594 if (file->f_mode & FMODE_WRITE)
1595 rc = filemap_write_and_wait(inode->i_mapping);
1597 cFYI(1, "Flush inode %p file %p rc %d", inode, file, rc);
1602 ssize_t cifs_user_read(struct file *file, char __user *read_data,
1603 size_t read_size, loff_t *poffset)
1606 unsigned int bytes_read = 0;
1607 unsigned int total_read = 0;
1608 unsigned int current_read_size;
1609 struct cifs_sb_info *cifs_sb;
1610 struct cifsTconInfo *pTcon;
1612 struct cifsFileInfo *open_file;
1613 char *smb_read_data;
1614 char __user *current_offset;
1615 struct smb_com_read_rsp *pSMBr;
1618 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1620 if (file->private_data == NULL) {
1625 open_file = file->private_data;
1626 pTcon = tlink_tcon(open_file->tlink);
1628 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1629 cFYI(1, "attempting read on write only file instance");
1631 for (total_read = 0, current_offset = read_data;
1632 read_size > total_read;
1633 total_read += bytes_read, current_offset += bytes_read) {
1634 current_read_size = min_t(const int, read_size - total_read,
1637 smb_read_data = NULL;
1638 while (rc == -EAGAIN) {
1639 int buf_type = CIFS_NO_BUFFER;
1640 if (open_file->invalidHandle) {
1641 rc = cifs_reopen_file(open_file, true);
1645 rc = CIFSSMBRead(xid, pTcon,
1647 current_read_size, *poffset,
1648 &bytes_read, &smb_read_data,
1650 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1651 if (smb_read_data) {
1652 if (copy_to_user(current_offset,
1654 4 /* RFC1001 length field */ +
1655 le16_to_cpu(pSMBr->DataOffset),
1659 if (buf_type == CIFS_SMALL_BUFFER)
1660 cifs_small_buf_release(smb_read_data);
1661 else if (buf_type == CIFS_LARGE_BUFFER)
1662 cifs_buf_release(smb_read_data);
1663 smb_read_data = NULL;
1666 if (rc || (bytes_read == 0)) {
1674 cifs_stats_bytes_read(pTcon, bytes_read);
1675 *poffset += bytes_read;
1683 static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
1687 unsigned int bytes_read = 0;
1688 unsigned int total_read;
1689 unsigned int current_read_size;
1690 struct cifs_sb_info *cifs_sb;
1691 struct cifsTconInfo *pTcon;
1693 char *current_offset;
1694 struct cifsFileInfo *open_file;
1695 int buf_type = CIFS_NO_BUFFER;
1698 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1700 if (file->private_data == NULL) {
1705 open_file = file->private_data;
1706 pTcon = tlink_tcon(open_file->tlink);
1708 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1709 cFYI(1, "attempting read on write only file instance");
1711 for (total_read = 0, current_offset = read_data;
1712 read_size > total_read;
1713 total_read += bytes_read, current_offset += bytes_read) {
1714 current_read_size = min_t(const int, read_size - total_read,
1716 /* For windows me and 9x we do not want to request more
1717 than it negotiated since it will refuse the read then */
1719 !(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
1720 current_read_size = min_t(const int, current_read_size,
1721 pTcon->ses->server->maxBuf - 128);
1724 while (rc == -EAGAIN) {
1725 if (open_file->invalidHandle) {
1726 rc = cifs_reopen_file(open_file, true);
1730 rc = CIFSSMBRead(xid, pTcon,
1732 current_read_size, *poffset,
1733 &bytes_read, ¤t_offset,
1736 if (rc || (bytes_read == 0)) {
1744 cifs_stats_bytes_read(pTcon, total_read);
1745 *poffset += bytes_read;
1752 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
1757 rc = cifs_revalidate_file(file);
1759 cFYI(1, "Validation prior to mmap failed, error=%d", rc);
1763 rc = generic_file_mmap(file, vma);
1769 static void cifs_copy_cache_pages(struct address_space *mapping,
1770 struct list_head *pages, int bytes_read, char *data)
1775 while (bytes_read > 0) {
1776 if (list_empty(pages))
1779 page = list_entry(pages->prev, struct page, lru);
1780 list_del(&page->lru);
1782 if (add_to_page_cache_lru(page, mapping, page->index,
1784 page_cache_release(page);
1785 cFYI(1, "Add page cache failed");
1786 data += PAGE_CACHE_SIZE;
1787 bytes_read -= PAGE_CACHE_SIZE;
1790 page_cache_release(page);
1792 target = kmap_atomic(page, KM_USER0);
1794 if (PAGE_CACHE_SIZE > bytes_read) {
1795 memcpy(target, data, bytes_read);
1796 /* zero the tail end of this partial page */
1797 memset(target + bytes_read, 0,
1798 PAGE_CACHE_SIZE - bytes_read);
1801 memcpy(target, data, PAGE_CACHE_SIZE);
1802 bytes_read -= PAGE_CACHE_SIZE;
1804 kunmap_atomic(target, KM_USER0);
1806 flush_dcache_page(page);
1807 SetPageUptodate(page);
1809 data += PAGE_CACHE_SIZE;
1811 /* add page to FS-Cache */
1812 cifs_readpage_to_fscache(mapping->host, page);
1817 static int cifs_readpages(struct file *file, struct address_space *mapping,
1818 struct list_head *page_list, unsigned num_pages)
1824 struct cifs_sb_info *cifs_sb;
1825 struct cifsTconInfo *pTcon;
1826 unsigned int bytes_read = 0;
1827 unsigned int read_size, i;
1828 char *smb_read_data = NULL;
1829 struct smb_com_read_rsp *pSMBr;
1830 struct cifsFileInfo *open_file;
1831 int buf_type = CIFS_NO_BUFFER;
1834 if (file->private_data == NULL) {
1839 open_file = file->private_data;
1840 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1841 pTcon = tlink_tcon(open_file->tlink);
1844 * Reads as many pages as possible from fscache. Returns -ENOBUFS
1845 * immediately if the cookie is negative
1847 rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
1852 cFYI(DBG2, "rpages: num pages %d", num_pages);
1853 for (i = 0; i < num_pages; ) {
1854 unsigned contig_pages;
1855 struct page *tmp_page;
1856 unsigned long expected_index;
1858 if (list_empty(page_list))
1861 page = list_entry(page_list->prev, struct page, lru);
1862 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1864 /* count adjacent pages that we will read into */
1867 list_entry(page_list->prev, struct page, lru)->index;
1868 list_for_each_entry_reverse(tmp_page, page_list, lru) {
1869 if (tmp_page->index == expected_index) {
1875 if (contig_pages + i > num_pages)
1876 contig_pages = num_pages - i;
1878 /* for reads over a certain size could initiate async
1881 read_size = contig_pages * PAGE_CACHE_SIZE;
1882 /* Read size needs to be in multiples of one page */
1883 read_size = min_t(const unsigned int, read_size,
1884 cifs_sb->rsize & PAGE_CACHE_MASK);
1885 cFYI(DBG2, "rpages: read size 0x%x contiguous pages %d",
1886 read_size, contig_pages);
1888 while (rc == -EAGAIN) {
1889 if (open_file->invalidHandle) {
1890 rc = cifs_reopen_file(open_file, true);
1895 rc = CIFSSMBRead(xid, pTcon,
1898 &bytes_read, &smb_read_data,
1900 /* BB more RC checks ? */
1901 if (rc == -EAGAIN) {
1902 if (smb_read_data) {
1903 if (buf_type == CIFS_SMALL_BUFFER)
1904 cifs_small_buf_release(smb_read_data);
1905 else if (buf_type == CIFS_LARGE_BUFFER)
1906 cifs_buf_release(smb_read_data);
1907 smb_read_data = NULL;
1911 if ((rc < 0) || (smb_read_data == NULL)) {
1912 cFYI(1, "Read error in readpages: %d", rc);
1914 } else if (bytes_read > 0) {
1915 task_io_account_read(bytes_read);
1916 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1917 cifs_copy_cache_pages(mapping, page_list, bytes_read,
1918 smb_read_data + 4 /* RFC1001 hdr */ +
1919 le16_to_cpu(pSMBr->DataOffset));
1921 i += bytes_read >> PAGE_CACHE_SHIFT;
1922 cifs_stats_bytes_read(pTcon, bytes_read);
1923 if ((bytes_read & PAGE_CACHE_MASK) != bytes_read) {
1924 i++; /* account for partial page */
1926 /* server copy of file can have smaller size
1928 /* BB do we need to verify this common case ?
1929 this case is ok - if we are at server EOF
1930 we will hit it on next read */
1935 cFYI(1, "No bytes read (%d) at offset %lld . "
1936 "Cleaning remaining pages from readahead list",
1937 bytes_read, offset);
1938 /* BB turn off caching and do new lookup on
1939 file size at server? */
1942 if (smb_read_data) {
1943 if (buf_type == CIFS_SMALL_BUFFER)
1944 cifs_small_buf_release(smb_read_data);
1945 else if (buf_type == CIFS_LARGE_BUFFER)
1946 cifs_buf_release(smb_read_data);
1947 smb_read_data = NULL;
1952 /* need to free smb_read_data buf before exit */
1953 if (smb_read_data) {
1954 if (buf_type == CIFS_SMALL_BUFFER)
1955 cifs_small_buf_release(smb_read_data);
1956 else if (buf_type == CIFS_LARGE_BUFFER)
1957 cifs_buf_release(smb_read_data);
1958 smb_read_data = NULL;
1966 static int cifs_readpage_worker(struct file *file, struct page *page,
1972 /* Is the page cached? */
1973 rc = cifs_readpage_from_fscache(file->f_path.dentry->d_inode, page);
1977 page_cache_get(page);
1978 read_data = kmap(page);
1979 /* for reads over a certain size could initiate async read ahead */
1981 rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
1986 cFYI(1, "Bytes read %d", rc);
1988 file->f_path.dentry->d_inode->i_atime =
1989 current_fs_time(file->f_path.dentry->d_inode->i_sb);
1991 if (PAGE_CACHE_SIZE > rc)
1992 memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
1994 flush_dcache_page(page);
1995 SetPageUptodate(page);
1997 /* send this page to the cache */
1998 cifs_readpage_to_fscache(file->f_path.dentry->d_inode, page);
2004 page_cache_release(page);
2010 static int cifs_readpage(struct file *file, struct page *page)
2012 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
2018 if (file->private_data == NULL) {
2024 cFYI(1, "readpage %p at offset %d 0x%x\n",
2025 page, (int)offset, (int)offset);
2027 rc = cifs_readpage_worker(file, page, &offset);
2035 static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
2037 struct cifsFileInfo *open_file;
2039 spin_lock(&cifs_file_list_lock);
2040 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
2041 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
2042 spin_unlock(&cifs_file_list_lock);
2046 spin_unlock(&cifs_file_list_lock);
2050 /* We do not want to update the file size from server for inodes
2051 open for write - to avoid races with writepage extending
2052 the file - in the future we could consider allowing
2053 refreshing the inode only on increases in the file size
2054 but this is tricky to do without racing with writebehind
2055 page caching in the current Linux kernel design */
2056 bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
2061 if (is_inode_writable(cifsInode)) {
2062 /* This inode is open for write at least once */
2063 struct cifs_sb_info *cifs_sb;
2065 cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
2066 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
2067 /* since no page cache to corrupt on directio
2068 we can change size safely */
2072 if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
2080 static int cifs_write_begin(struct file *file, struct address_space *mapping,
2081 loff_t pos, unsigned len, unsigned flags,
2082 struct page **pagep, void **fsdata)
2084 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
2085 loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
2086 loff_t page_start = pos & PAGE_MASK;
2091 cFYI(1, "write_begin from %lld len %d", (long long)pos, len);
2093 page = grab_cache_page_write_begin(mapping, index, flags);
2099 if (PageUptodate(page))
2103 * If we write a full page it will be up to date, no need to read from
2104 * the server. If the write is short, we'll end up doing a sync write
2107 if (len == PAGE_CACHE_SIZE)
2111 * optimize away the read when we have an oplock, and we're not
2112 * expecting to use any of the data we'd be reading in. That
2113 * is, when the page lies beyond the EOF, or straddles the EOF
2114 * and the write will cover all of the existing data.
2116 if (CIFS_I(mapping->host)->clientCanCacheRead) {
2117 i_size = i_size_read(mapping->host);
2118 if (page_start >= i_size ||
2119 (offset == 0 && (pos + len) >= i_size)) {
2120 zero_user_segments(page, 0, offset,
2124 * PageChecked means that the parts of the page
2125 * to which we're not writing are considered up
2126 * to date. Once the data is copied to the
2127 * page, it can be set uptodate.
2129 SetPageChecked(page);
2134 if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
2136 * might as well read a page, it is fast enough. If we get
2137 * an error, we don't need to return it. cifs_write_end will
2138 * do a sync write instead since PG_uptodate isn't set.
2140 cifs_readpage_worker(file, page, &page_start);
2142 /* we could try using another file handle if there is one -
2143 but how would we lock it to prevent close of that handle
2144 racing with this read? In any case
2145 this will be written out by write_end so is fine */
2152 static int cifs_release_page(struct page *page, gfp_t gfp)
2154 if (PagePrivate(page))
2157 return cifs_fscache_release_page(page, gfp);
2160 static void cifs_invalidate_page(struct page *page, unsigned long offset)
2162 struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
2165 cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
2168 void cifs_oplock_break(struct work_struct *work)
2170 struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
2172 struct inode *inode = cfile->dentry->d_inode;
2173 struct cifsInodeInfo *cinode = CIFS_I(inode);
2176 if (inode && S_ISREG(inode->i_mode)) {
2177 if (cinode->clientCanCacheRead)
2178 break_lease(inode, O_RDONLY);
2180 break_lease(inode, O_WRONLY);
2181 rc = filemap_fdatawrite(inode->i_mapping);
2182 if (cinode->clientCanCacheRead == 0) {
2183 rc = filemap_fdatawait(inode->i_mapping);
2184 mapping_set_error(inode->i_mapping, rc);
2185 invalidate_remote_inode(inode);
2187 cFYI(1, "Oplock flush inode %p rc %d", inode, rc);
2191 * releasing stale oplock after recent reconnect of smb session using
2192 * a now incorrect file handle is not a data integrity issue but do
2193 * not bother sending an oplock release if session to server still is
2194 * disconnected since oplock already released by the server
2196 if (!cfile->oplock_break_cancelled) {
2197 rc = CIFSSMBLock(0, tlink_tcon(cfile->tlink), cfile->netfid, 0,
2198 0, 0, 0, LOCKING_ANDX_OPLOCK_RELEASE, false,
2199 cinode->clientCanCacheRead ? 1 : 0);
2200 cFYI(1, "Oplock release rc = %d", rc);
2204 * We might have kicked in before is_valid_oplock_break()
2205 * finished grabbing reference for us. Make sure it's done by
2206 * waiting for cifs_file_list_lock.
2208 spin_lock(&cifs_file_list_lock);
2209 spin_unlock(&cifs_file_list_lock);
2211 cifs_oplock_break_put(cfile);
2214 /* must be called while holding cifs_file_list_lock */
2215 void cifs_oplock_break_get(struct cifsFileInfo *cfile)
2217 cifs_sb_active(cfile->dentry->d_sb);
2218 cifsFileInfo_get(cfile);
2221 void cifs_oplock_break_put(struct cifsFileInfo *cfile)
2223 struct super_block *sb = cfile->dentry->d_sb;
2225 cifsFileInfo_put(cfile);
2226 cifs_sb_deactive(sb);
2229 const struct address_space_operations cifs_addr_ops = {
2230 .readpage = cifs_readpage,
2231 .readpages = cifs_readpages,
2232 .writepage = cifs_writepage,
2233 .writepages = cifs_writepages,
2234 .write_begin = cifs_write_begin,
2235 .write_end = cifs_write_end,
2236 .set_page_dirty = __set_page_dirty_nobuffers,
2237 .releasepage = cifs_release_page,
2238 .invalidatepage = cifs_invalidate_page,
2239 /* .sync_page = cifs_sync_page, */
2244 * cifs_readpages requires the server to support a buffer large enough to
2245 * contain the header plus one complete page of data. Otherwise, we need
2246 * to leave cifs_readpages out of the address space operations.
2248 const struct address_space_operations cifs_addr_ops_smallbuf = {
2249 .readpage = cifs_readpage,
2250 .writepage = cifs_writepage,
2251 .writepages = cifs_writepages,
2252 .write_begin = cifs_write_begin,
2253 .write_end = cifs_write_end,
2254 .set_page_dirty = __set_page_dirty_nobuffers,
2255 .releasepage = cifs_release_page,
2256 .invalidatepage = cifs_invalidate_page,
2257 /* .sync_page = cifs_sync_page, */