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[PATCH] neofb: avoid resetting display config on unblank
[linux-2.6-block.git] / fs / cifs / file.c
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1da177e4
LT		 1/*
2 * fs/cifs/file.c
3 *
4 * vfs operations that deal with files
5 *
6 * Copyright (C) International Business Machines Corp., 2002,2003
7 * Author(s): Steve French (sfrench@us.ibm.com)
8 *
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23#include <linux/fs.h>
37c0eb46 24#include <linux/backing-dev.h>
1da177e4
LT		 25#include <linux/stat.h>
26#include <linux/fcntl.h>
37c0eb46 27#include <linux/mpage.h>
1da177e4
LT		 28#include <linux/pagemap.h>
29#include <linux/pagevec.h>
30#include <linux/smp_lock.h>
37c0eb46 31#include <linux/writeback.h>
23e7dd7d 32#include <linux/delay.h>
1da177e4
LT		 33#include <asm/div64.h>
34#include "cifsfs.h"
35#include "cifspdu.h"
36#include "cifsglob.h"
37#include "cifsproto.h"
38#include "cifs_unicode.h"
39#include "cifs_debug.h"
40#include "cifs_fs_sb.h"
41
42static inline struct cifsFileInfo *cifs_init_private(
43 struct cifsFileInfo *private_data, struct inode *inode,
44 struct file *file, __u16 netfid)
45{
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;
23e7dd7d
SF		 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);
1da177e4
LT		 59
60 return private_data;
61}
62
63static inline int cifs_convert_flags(unsigned int flags)
64{
65 if ((flags & O_ACCMODE) == O_RDONLY)
66 return GENERIC_READ;
67 else if ((flags & O_ACCMODE) == O_WRONLY)
68 return GENERIC_WRITE;
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);
74 }
75
76 return 0x20197;
77}
78
79static inline int cifs_get_disposition(unsigned int flags)
80{
81 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
82 return FILE_CREATE;
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)
86 return FILE_OPEN_IF;
87 else
88 return FILE_OPEN;
89}
90
91/* all arguments to this function must be checked for validity in caller */
92static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
93 struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile,
94 struct cifsTconInfo *pTcon, int *oplock, FILE_ALL_INFO *buf,
95 char *full_path, int xid)
96{
97 struct timespec temp;
98 int rc;
99
100 /* want handles we can use to read with first
101 in the list so we do not have to walk the
102 list to search for one in prepare_write */
103 if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
104 list_add_tail(&pCifsFile->flist,
105 &pCifsInode->openFileList);
106 } else {
107 list_add(&pCifsFile->flist,
108 &pCifsInode->openFileList);
109 }
110 write_unlock(&GlobalSMBSeslock);
111 write_unlock(&file->f_owner.lock);
112 if (pCifsInode->clientCanCacheRead) {
113 /* we have the inode open somewhere else
114 no need to discard cache data */
115 goto client_can_cache;
116 }
117
118 /* BB need same check in cifs_create too? */
119 /* if not oplocked, invalidate inode pages if mtime or file
120 size changed */
121 temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime));
122 if (timespec_equal(&file->f_dentry->d_inode->i_mtime, &temp) &&
123 (file->f_dentry->d_inode->i_size ==
124 (loff_t)le64_to_cpu(buf->EndOfFile))) {
125 cFYI(1, ("inode unchanged on server"));
126 } else {
127 if (file->f_dentry->d_inode->i_mapping) {
128 /* BB no need to lock inode until after invalidate
129 since namei code should already have it locked? */
28fd1298 130 filemap_write_and_wait(file->f_dentry->d_inode->i_mapping);
1da177e4
LT		 131 }
132 cFYI(1, ("invalidating remote inode since open detected it "
133 "changed"));
134 invalidate_remote_inode(file->f_dentry->d_inode);
135 }
136
137client_can_cache:
138 if (pTcon->ses->capabilities & CAP_UNIX)
139 rc = cifs_get_inode_info_unix(&file->f_dentry->d_inode,
140 full_path, inode->i_sb, xid);
141 else
142 rc = cifs_get_inode_info(&file->f_dentry->d_inode,
143 full_path, buf, inode->i_sb, xid);
144
145 if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) {
146 pCifsInode->clientCanCacheAll = TRUE;
147 pCifsInode->clientCanCacheRead = TRUE;
148 cFYI(1, ("Exclusive Oplock granted on inode %p",
149 file->f_dentry->d_inode));
150 } else if ((*oplock & 0xF) == OPLOCK_READ)
151 pCifsInode->clientCanCacheRead = TRUE;
152
153 return rc;
154}
155
156int cifs_open(struct inode *inode, struct file *file)
157{
158 int rc = -EACCES;
159 int xid, oplock;
160 struct cifs_sb_info *cifs_sb;
161 struct cifsTconInfo *pTcon;
162 struct cifsFileInfo *pCifsFile;
163 struct cifsInodeInfo *pCifsInode;
164 struct list_head *tmp;
165 char *full_path = NULL;
166 int desiredAccess;
167 int disposition;
168 __u16 netfid;
169 FILE_ALL_INFO *buf = NULL;
170
171 xid = GetXid();
172
173 cifs_sb = CIFS_SB(inode->i_sb);
174 pTcon = cifs_sb->tcon;
175
176 if (file->f_flags & O_CREAT) {
177 /* search inode for this file and fill in file->private_data */
178 pCifsInode = CIFS_I(file->f_dentry->d_inode);
179 read_lock(&GlobalSMBSeslock);
180 list_for_each(tmp, &pCifsInode->openFileList) {
181 pCifsFile = list_entry(tmp, struct cifsFileInfo,
182 flist);
183 if ((pCifsFile->pfile == NULL) &&
184 (pCifsFile->pid == current->tgid)) {
185 /* mode set in cifs_create */
186
187 /* needed for writepage */
188 pCifsFile->pfile = file;
189
190 file->private_data = pCifsFile;
191 break;
192 }
193 }
194 read_unlock(&GlobalSMBSeslock);
195 if (file->private_data != NULL) {
196 rc = 0;
197 FreeXid(xid);
198 return rc;
199 } else {
200 if (file->f_flags & O_EXCL)
201 cERROR(1, ("could not find file instance for "
202 "new file %p ", file));
203 }
204 }
205
206 down(&inode->i_sb->s_vfs_rename_sem);
7f57356b 207 full_path = build_path_from_dentry(file->f_dentry);
1da177e4
LT		 208 up(&inode->i_sb->s_vfs_rename_sem);
209 if (full_path == NULL) {
210 FreeXid(xid);
211 return -ENOMEM;
212 }
213
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);
217
218/*********************************************************************
219 * open flag mapping table:
220 *
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
228 *
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)
234 *?
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 *********************************************************************/
241
242 disposition = cifs_get_disposition(file->f_flags);
243
244 if (oplockEnabled)
245 oplock = REQ_OPLOCK;
246 else
247 oplock = FALSE;
248
249 /* BB pass O_SYNC flag through on file attributes .. BB */
250
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) */
254
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);
259 if (!buf) {
260 rc = -ENOMEM;
261 goto out;
262 }
263 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
264 CREATE_NOT_DIR, &netfid, &oplock, buf,
737b758c
SF		 265 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
266 & CIFS_MOUNT_MAP_SPECIAL_CHR);
a9d02ad4
SF		 267 if (rc == -EIO) {
268 /* Old server, try legacy style OpenX */
269 rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
270 desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
271 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
272 & CIFS_MOUNT_MAP_SPECIAL_CHR);
273 }
1da177e4
LT		 274 if (rc) {
275 cFYI(1, ("cifs_open returned 0x%x ", rc));
276 goto out;
277 }
278 file->private_data =
279 kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
280 if (file->private_data == NULL) {
281 rc = -ENOMEM;
282 goto out;
283 }
284 pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
285 write_lock(&file->f_owner.lock);
286 write_lock(&GlobalSMBSeslock);
287 list_add(&pCifsFile->tlist, &pTcon->openFileList);
288
289 pCifsInode = CIFS_I(file->f_dentry->d_inode);
290 if (pCifsInode) {
291 rc = cifs_open_inode_helper(inode, file, pCifsInode,
292 pCifsFile, pTcon,
293 &oplock, buf, full_path, xid);
294 } else {
295 write_unlock(&GlobalSMBSeslock);
296 write_unlock(&file->f_owner.lock);
297 }
298
299 if (oplock & CIFS_CREATE_ACTION) {
300 /* time to set mode which we can not set earlier due to
301 problems creating new read-only files */
302 if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
303 CIFSSMBUnixSetPerms(xid, pTcon, full_path,
304 inode->i_mode,
305 (__u64)-1, (__u64)-1, 0 /* dev */,
737b758c
SF		 306 cifs_sb->local_nls,
307 cifs_sb->mnt_cifs_flags &
308 CIFS_MOUNT_MAP_SPECIAL_CHR);
1da177e4
LT		 309 } else {
310 /* BB implement via Windows security descriptors eg
311 CIFSSMBWinSetPerms(xid, pTcon, full_path, mode,
312 -1, -1, local_nls);
313 in the meantime could set r/o dos attribute when
314 perms are eg: mode & 0222 == 0 */
315 }
316 }
317
318out:
319 kfree(buf);
320 kfree(full_path);
321 FreeXid(xid);
322 return rc;
323}
324
325/* Try to reaquire byte range locks that were released when session */
326/* to server was lost */
327static int cifs_relock_file(struct cifsFileInfo *cifsFile)
328{
329 int rc = 0;
330
331/* BB list all locks open on this file and relock */
332
333 return rc;
334}
335
336static int cifs_reopen_file(struct inode *inode, struct file *file,
337 int can_flush)
338{
339 int rc = -EACCES;
340 int xid, oplock;
341 struct cifs_sb_info *cifs_sb;
342 struct cifsTconInfo *pTcon;
343 struct cifsFileInfo *pCifsFile;
344 struct cifsInodeInfo *pCifsInode;
345 char *full_path = NULL;
346 int desiredAccess;
347 int disposition = FILE_OPEN;
348 __u16 netfid;
349
350 if (inode == NULL)
351 return -EBADF;
352 if (file->private_data) {
353 pCifsFile = (struct cifsFileInfo *)file->private_data;
354 } else
355 return -EBADF;
356
357 xid = GetXid();
358 down(&pCifsFile->fh_sem);
359 if (pCifsFile->invalidHandle == FALSE) {
360 up(&pCifsFile->fh_sem);
361 FreeXid(xid);
362 return 0;
363 }
364
365 if (file->f_dentry == NULL) {
366 up(&pCifsFile->fh_sem);
367 cFYI(1, ("failed file reopen, no valid name if dentry freed"));
368 FreeXid(xid);
369 return -EBADF;
370 }
371 cifs_sb = CIFS_SB(inode->i_sb);
372 pTcon = cifs_sb->tcon;
373/* can not grab rename sem here because various ops, including
374 those that already have the rename sem can end up causing writepage
375 to get called and if the server was down that means we end up here,
376 and we can never tell if the caller already has the rename_sem */
7f57356b 377 full_path = build_path_from_dentry(file->f_dentry);
1da177e4
LT		 378 if (full_path == NULL) {
379 up(&pCifsFile->fh_sem);
380 FreeXid(xid);
381 return -ENOMEM;
382 }
383
384 cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
385 inode, file->f_flags,full_path));
386 desiredAccess = cifs_convert_flags(file->f_flags);
387
388 if (oplockEnabled)
389 oplock = REQ_OPLOCK;
390 else
391 oplock = FALSE;
392
393 /* Can not refresh inode by passing in file_info buf to be returned
394 by SMBOpen and then calling get_inode_info with returned buf
395 since file might have write behind data that needs to be flushed
396 and server version of file size can be stale. If we knew for sure
397 that inode was not dirty locally we could do this */
398
399/* buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
400 if (buf == 0) {
401 up(&pCifsFile->fh_sem);
402 kfree(full_path);
403 FreeXid(xid);
404 return -ENOMEM;
405 } */
406 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
407 CREATE_NOT_DIR, &netfid, &oplock, NULL,
737b758c
SF		 408 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
409 CIFS_MOUNT_MAP_SPECIAL_CHR);
1da177e4
LT		 410 if (rc) {
411 up(&pCifsFile->fh_sem);
412 cFYI(1, ("cifs_open returned 0x%x ", rc));
413 cFYI(1, ("oplock: %d ", oplock));
414 } else {
415 pCifsFile->netfid = netfid;
416 pCifsFile->invalidHandle = FALSE;
417 up(&pCifsFile->fh_sem);
418 pCifsInode = CIFS_I(inode);
419 if (pCifsInode) {
420 if (can_flush) {
28fd1298 421 filemap_write_and_wait(inode->i_mapping);
1da177e4
LT		 422 /* temporarily disable caching while we
423 go to server to get inode info */
424 pCifsInode->clientCanCacheAll = FALSE;
425 pCifsInode->clientCanCacheRead = FALSE;
426 if (pTcon->ses->capabilities & CAP_UNIX)
427 rc = cifs_get_inode_info_unix(&inode,
428 full_path, inode->i_sb, xid);
429 else
430 rc = cifs_get_inode_info(&inode,
431 full_path, NULL, inode->i_sb,
432 xid);
433 } /* else we are writing out data to server already
434 and could deadlock if we tried to flush data, and
435 since we do not know if we have data that would
436 invalidate the current end of file on the server
437 we can not go to the server to get the new inod
438 info */
439 if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
440 pCifsInode->clientCanCacheAll = TRUE;
441 pCifsInode->clientCanCacheRead = TRUE;
442 cFYI(1, ("Exclusive Oplock granted on inode %p",
443 file->f_dentry->d_inode));
444 } else if ((oplock & 0xF) == OPLOCK_READ) {
445 pCifsInode->clientCanCacheRead = TRUE;
446 pCifsInode->clientCanCacheAll = FALSE;
447 } else {
448 pCifsInode->clientCanCacheRead = FALSE;
449 pCifsInode->clientCanCacheAll = FALSE;
450 }
451 cifs_relock_file(pCifsFile);
452 }
453 }
454
455 kfree(full_path);
456 FreeXid(xid);
457 return rc;
458}
459
460int cifs_close(struct inode *inode, struct file *file)
461{
462 int rc = 0;
463 int xid;
464 struct cifs_sb_info *cifs_sb;
465 struct cifsTconInfo *pTcon;
466 struct cifsFileInfo *pSMBFile =
467 (struct cifsFileInfo *)file->private_data;
468
469 xid = GetXid();
470
471 cifs_sb = CIFS_SB(inode->i_sb);
472 pTcon = cifs_sb->tcon;
473 if (pSMBFile) {
474 pSMBFile->closePend = TRUE;
475 write_lock(&file->f_owner.lock);
476 if (pTcon) {
477 /* no sense reconnecting to close a file that is
478 already closed */
479 if (pTcon->tidStatus != CifsNeedReconnect) {
23e7dd7d
SF		 480 int timeout = 2;
481 while((atomic_read(&pSMBFile->wrtPending) != 0)
482 && (timeout < 1000) ) {
483 /* Give write a better chance to get to
484 server ahead of the close. We do not
485 want to add a wait_q here as it would
486 increase the memory utilization as
487 the struct would be in each open file,
488 but this should give enough time to
489 clear the socket */
c119b87d 490 write_unlock(&file->f_owner.lock);
23e7dd7d
SF		 491 cERROR(1,("close with pending writes"));
492 msleep(timeout);
c119b87d 493 write_lock(&file->f_owner.lock);
23e7dd7d
SF		 494 timeout *= 4;
495 }
1da177e4
LT		 496 write_unlock(&file->f_owner.lock);
497 rc = CIFSSMBClose(xid, pTcon,
498 pSMBFile->netfid);
499 write_lock(&file->f_owner.lock);
500 }
501 }
cbe0476f 502 write_lock(&GlobalSMBSeslock);
1da177e4
LT		 503 list_del(&pSMBFile->flist);
504 list_del(&pSMBFile->tlist);
cbe0476f 505 write_unlock(&GlobalSMBSeslock);
1da177e4
LT		 506 write_unlock(&file->f_owner.lock);
507 kfree(pSMBFile->search_resume_name);
508 kfree(file->private_data);
509 file->private_data = NULL;
510 } else
511 rc = -EBADF;
512
513 if (list_empty(&(CIFS_I(inode)->openFileList))) {
514 cFYI(1, ("closing last open instance for inode %p", inode));
515 /* if the file is not open we do not know if we can cache info
516 on this inode, much less write behind and read ahead */
517 CIFS_I(inode)->clientCanCacheRead = FALSE;
518 CIFS_I(inode)->clientCanCacheAll = FALSE;
519 }
520 if ((rc ==0) && CIFS_I(inode)->write_behind_rc)
521 rc = CIFS_I(inode)->write_behind_rc;
522 FreeXid(xid);
523 return rc;
524}
525
526int cifs_closedir(struct inode *inode, struct file *file)
527{
528 int rc = 0;
529 int xid;
530 struct cifsFileInfo *pCFileStruct =
531 (struct cifsFileInfo *)file->private_data;
532 char *ptmp;
533
534 cFYI(1, ("Closedir inode = 0x%p with ", inode));
535
536 xid = GetXid();
537
538 if (pCFileStruct) {
539 struct cifsTconInfo *pTcon;
540 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_dentry->d_sb);
541
542 pTcon = cifs_sb->tcon;
543
544 cFYI(1, ("Freeing private data in close dir"));
31ca3bc3
SF		 545 if ((pCFileStruct->srch_inf.endOfSearch == FALSE) &&
546 (pCFileStruct->invalidHandle == FALSE)) {
1da177e4
LT		 547 pCFileStruct->invalidHandle = TRUE;
548 rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
549 cFYI(1, ("Closing uncompleted readdir with rc %d",
550 rc));
551 /* not much we can do if it fails anyway, ignore rc */
552 rc = 0;
553 }
554 ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
555 if (ptmp) {
ec637e3f 556 cFYI(1, ("closedir free smb buf in srch struct"));
1da177e4
LT		 557 pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
558 cifs_buf_release(ptmp);
559 }
560 ptmp = pCFileStruct->search_resume_name;
561 if (ptmp) {
ec637e3f 562 cFYI(1, ("closedir free resume name"));
1da177e4
LT		 563 pCFileStruct->search_resume_name = NULL;
564 kfree(ptmp);
565 }
566 kfree(file->private_data);
567 file->private_data = NULL;
568 }
569 /* BB can we lock the filestruct while this is going on? */
570 FreeXid(xid);
571 return rc;
572}
573
574int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
575{
576 int rc, xid;
577 __u32 lockType = LOCKING_ANDX_LARGE_FILES;
578 __u32 numLock = 0;
579 __u32 numUnlock = 0;
580 __u64 length;
581 int wait_flag = FALSE;
582 struct cifs_sb_info *cifs_sb;
583 struct cifsTconInfo *pTcon;
584
585 length = 1 + pfLock->fl_end - pfLock->fl_start;
586 rc = -EACCES;
587 xid = GetXid();
588
589 cFYI(1, ("Lock parm: 0x%x flockflags: "
590 "0x%x flocktype: 0x%x start: %lld end: %lld",
591 cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
592 pfLock->fl_end));
593
594 if (pfLock->fl_flags & FL_POSIX)
595 cFYI(1, ("Posix "));
596 if (pfLock->fl_flags & FL_FLOCK)
597 cFYI(1, ("Flock "));
598 if (pfLock->fl_flags & FL_SLEEP) {
599 cFYI(1, ("Blocking lock "));
600 wait_flag = TRUE;
601 }
602 if (pfLock->fl_flags & FL_ACCESS)
603 cFYI(1, ("Process suspended by mandatory locking - "
604 "not implemented yet "));
605 if (pfLock->fl_flags & FL_LEASE)
606 cFYI(1, ("Lease on file - not implemented yet"));
607 if (pfLock->fl_flags &
608 (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
609 cFYI(1, ("Unknown lock flags 0x%x", pfLock->fl_flags));
610
611 if (pfLock->fl_type == F_WRLCK) {
612 cFYI(1, ("F_WRLCK "));
613 numLock = 1;
614 } else if (pfLock->fl_type == F_UNLCK) {
615 cFYI(1, ("F_UNLCK "));
616 numUnlock = 1;
617 } else if (pfLock->fl_type == F_RDLCK) {
618 cFYI(1, ("F_RDLCK "));
619 lockType |= LOCKING_ANDX_SHARED_LOCK;
620 numLock = 1;
621 } else if (pfLock->fl_type == F_EXLCK) {
622 cFYI(1, ("F_EXLCK "));
623 numLock = 1;
624 } else if (pfLock->fl_type == F_SHLCK) {
625 cFYI(1, ("F_SHLCK "));
626 lockType |= LOCKING_ANDX_SHARED_LOCK;
627 numLock = 1;
628 } else
629 cFYI(1, ("Unknown type of lock "));
630
631 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
632 pTcon = cifs_sb->tcon;
633
634 if (file->private_data == NULL) {
635 FreeXid(xid);
636 return -EBADF;
637 }
638
639 if (IS_GETLK(cmd)) {
640 rc = CIFSSMBLock(xid, pTcon,
641 ((struct cifsFileInfo *)file->
642 private_data)->netfid,
643 length,
644 pfLock->fl_start, 0, 1, lockType,
645 0 /* wait flag */ );
646 if (rc == 0) {
647 rc = CIFSSMBLock(xid, pTcon,
648 ((struct cifsFileInfo *) file->
649 private_data)->netfid,
650 length,
651 pfLock->fl_start, 1 /* numUnlock */ ,
652 0 /* numLock */ , lockType,
653 0 /* wait flag */ );
654 pfLock->fl_type = F_UNLCK;
655 if (rc != 0)
656 cERROR(1, ("Error unlocking previously locked "
657 "range %d during test of lock ",
658 rc));
659 rc = 0;
660
661 } else {
662 /* if rc == ERR_SHARING_VIOLATION ? */
663 rc = 0; /* do not change lock type to unlock
664 since range in use */
665 }
666
667 FreeXid(xid);
668 return rc;
669 }
670
671 rc = CIFSSMBLock(xid, pTcon,
672 ((struct cifsFileInfo *) file->private_data)->
673 netfid, length,
674 pfLock->fl_start, numUnlock, numLock, lockType,
675 wait_flag);
d634cc15 676 if (pfLock->fl_flags & FL_POSIX)
1da177e4
LT		 677 posix_lock_file_wait(file, pfLock);
678 FreeXid(xid);
679 return rc;
680}
681
682ssize_t cifs_user_write(struct file *file, const char __user *write_data,
683 size_t write_size, loff_t *poffset)
684{
685 int rc = 0;
686 unsigned int bytes_written = 0;
687 unsigned int total_written;
688 struct cifs_sb_info *cifs_sb;
689 struct cifsTconInfo *pTcon;
690 int xid, long_op;
691 struct cifsFileInfo *open_file;
692
693 if (file->f_dentry == NULL)
694 return -EBADF;
695
696 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
697 if (cifs_sb == NULL)
698 return -EBADF;
699
700 pTcon = cifs_sb->tcon;
701
702 /* cFYI(1,
703 (" write %d bytes to offset %lld of %s", write_size,
704 *poffset, file->f_dentry->d_name.name)); */
705
706 if (file->private_data == NULL)
707 return -EBADF;
708 else
709 open_file = (struct cifsFileInfo *) file->private_data;
710
711 xid = GetXid();
712 if (file->f_dentry->d_inode == NULL) {
713 FreeXid(xid);
714 return -EBADF;
715 }
716
717 if (*poffset > file->f_dentry->d_inode->i_size)
718 long_op = 2; /* writes past end of file can take a long time */
719 else
720 long_op = 1;
721
722 for (total_written = 0; write_size > total_written;
723 total_written += bytes_written) {
724 rc = -EAGAIN;
725 while (rc == -EAGAIN) {
726 if (file->private_data == NULL) {
727 /* file has been closed on us */
728 FreeXid(xid);
729 /* if we have gotten here we have written some data
730 and blocked, and the file has been freed on us while
731 we blocked so return what we managed to write */
732 return total_written;
733 }
734 if (open_file->closePend) {
735 FreeXid(xid);
736 if (total_written)
737 return total_written;
738 else
739 return -EBADF;
740 }
741 if (open_file->invalidHandle) {
742 if ((file->f_dentry == NULL) ||
743 (file->f_dentry->d_inode == NULL)) {
744 FreeXid(xid);
745 return total_written;
746 }
747 /* we could deadlock if we called
748 filemap_fdatawait from here so tell
749 reopen_file not to flush data to server
750 now */
751 rc = cifs_reopen_file(file->f_dentry->d_inode,
752 file, FALSE);
753 if (rc != 0)
754 break;
755 }
756
757 rc = CIFSSMBWrite(xid, pTcon,
758 open_file->netfid,
759 min_t(const int, cifs_sb->wsize,
760 write_size - total_written),
761 *poffset, &bytes_written,
762 NULL, write_data + total_written, long_op);
763 }
764 if (rc || (bytes_written == 0)) {
765 if (total_written)
766 break;
767 else {
768 FreeXid(xid);
769 return rc;
770 }
771 } else
772 *poffset += bytes_written;
773 long_op = FALSE; /* subsequent writes fast -
774 15 seconds is plenty */
775 }
776
a4544347 777 cifs_stats_bytes_written(pTcon, total_written);
1da177e4
LT		 778
779 /* since the write may have blocked check these pointers again */
780 if (file->f_dentry) {
781 if (file->f_dentry->d_inode) {
782 struct inode *inode = file->f_dentry->d_inode;
783 inode->i_ctime = inode->i_mtime =
784 current_fs_time(inode->i_sb);
785 if (total_written > 0) {
786 if (*poffset > file->f_dentry->d_inode->i_size)
787 i_size_write(file->f_dentry->d_inode,
788 *poffset);
789 }
790 mark_inode_dirty_sync(file->f_dentry->d_inode);
791 }
792 }
793 FreeXid(xid);
794 return total_written;
795}
796
797static ssize_t cifs_write(struct file *file, const char *write_data,
798 size_t write_size, loff_t *poffset)
799{
800 int rc = 0;
801 unsigned int bytes_written = 0;
802 unsigned int total_written;
803 struct cifs_sb_info *cifs_sb;
804 struct cifsTconInfo *pTcon;
805 int xid, long_op;
806 struct cifsFileInfo *open_file;
807
808 if (file->f_dentry == NULL)
809 return -EBADF;
810
811 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
812 if (cifs_sb == NULL)
813 return -EBADF;
814
815 pTcon = cifs_sb->tcon;
816
ab2f218f
SF		 817 cFYI(1,("write %zd bytes to offset %lld of %s", write_size,
818 *poffset, file->f_dentry->d_name.name));
1da177e4
LT		 819
820 if (file->private_data == NULL)
821 return -EBADF;
822 else
823 open_file = (struct cifsFileInfo *)file->private_data;
824
825 xid = GetXid();
826 if (file->f_dentry->d_inode == NULL) {
827 FreeXid(xid);
828 return -EBADF;
829 }
830
831 if (*poffset > file->f_dentry->d_inode->i_size)
832 long_op = 2; /* writes past end of file can take a long time */
833 else
834 long_op = 1;
835
836 for (total_written = 0; write_size > total_written;
837 total_written += bytes_written) {
838 rc = -EAGAIN;
839 while (rc == -EAGAIN) {
840 if (file->private_data == NULL) {
841 /* file has been closed on us */
842 FreeXid(xid);
843 /* if we have gotten here we have written some data
844 and blocked, and the file has been freed on us
845 while we blocked so return what we managed to
846 write */
847 return total_written;
848 }
849 if (open_file->closePend) {
850 FreeXid(xid);
851 if (total_written)
852 return total_written;
853 else
854 return -EBADF;
855 }
856 if (open_file->invalidHandle) {
857 if ((file->f_dentry == NULL) ||
858 (file->f_dentry->d_inode == NULL)) {
859 FreeXid(xid);
860 return total_written;
861 }
862 /* we could deadlock if we called
863 filemap_fdatawait from here so tell
864 reopen_file not to flush data to
865 server now */
866 rc = cifs_reopen_file(file->f_dentry->d_inode,
867 file, FALSE);
868 if (rc != 0)
869 break;
870 }
d6e04ae6 871 /* BB FIXME We can not sign across two buffers yet */
ec637e3f
SF		 872 if((pTcon->ses->server->secMode &
873 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) == 0) {
3e84469d
SF		 874 struct kvec iov[2];
875 unsigned int len;
876
0ae0efad 877 len = min((size_t)cifs_sb->wsize,
3e84469d
SF		 878 write_size - total_written);
879 /* iov[0] is reserved for smb header */
880 iov[1].iov_base = (char *)write_data +
881 total_written;
882 iov[1].iov_len = len;
d6e04ae6 883 rc = CIFSSMBWrite2(xid, pTcon,
3e84469d 884 open_file->netfid, len,
d6e04ae6 885 *poffset, &bytes_written,
3e84469d 886 iov, 1, long_op);
d6e04ae6
SF		 887 } else
888 /* BB FIXME fixup indentation of line below */
1da177e4
LT		 889 rc = CIFSSMBWrite(xid, pTcon,
890 open_file->netfid,
891 min_t(const int, cifs_sb->wsize,
892 write_size - total_written),
893 *poffset, &bytes_written,
894 write_data + total_written, NULL, long_op);
895 }
896 if (rc || (bytes_written == 0)) {
897 if (total_written)
898 break;
899 else {
900 FreeXid(xid);
901 return rc;
902 }
903 } else
904 *poffset += bytes_written;
905 long_op = FALSE; /* subsequent writes fast -
906 15 seconds is plenty */
907 }
908
a4544347 909 cifs_stats_bytes_written(pTcon, total_written);
1da177e4
LT		 910
911 /* since the write may have blocked check these pointers again */
912 if (file->f_dentry) {
913 if (file->f_dentry->d_inode) {
914 file->f_dentry->d_inode->i_ctime =
915 file->f_dentry->d_inode->i_mtime = CURRENT_TIME;
916 if (total_written > 0) {
917 if (*poffset > file->f_dentry->d_inode->i_size)
918 i_size_write(file->f_dentry->d_inode,
919 *poffset);
920 }
921 mark_inode_dirty_sync(file->f_dentry->d_inode);
922 }
923 }
924 FreeXid(xid);
925 return total_written;
926}
927
dd99cd80 928struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
6148a742
SF		 929{
930 struct cifsFileInfo *open_file;
dd99cd80 931 int rc;
6148a742
SF		 932
933 read_lock(&GlobalSMBSeslock);
934 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
935 if (open_file->closePend)
936 continue;
937 if (open_file->pfile &&
938 ((open_file->pfile->f_flags & O_RDWR) ||
939 (open_file->pfile->f_flags & O_WRONLY))) {
23e7dd7d 940 atomic_inc(&open_file->wrtPending);
6148a742 941 read_unlock(&GlobalSMBSeslock);
0ae0efad 942 if((open_file->invalidHandle) &&
23e7dd7d 943 (!open_file->closePend) /* BB fixme -since the second clause can not be true remove it BB */) {
dd99cd80 944 rc = cifs_reopen_file(&cifs_inode->vfs_inode,
37c0eb46
SF		 945 open_file->pfile, FALSE);
946 /* if it fails, try another handle - might be */
947 /* dangerous to hold up writepages with retry */
948 if(rc) {
4a77118c 949 cFYI(1,("failed on reopen file in wp"));
37c0eb46 950 read_lock(&GlobalSMBSeslock);
23e7dd7d
SF		 951 /* can not use this handle, no write
952 pending on this one after all */
953 atomic_dec
954 (&open_file->wrtPending);
37c0eb46
SF		 955 continue;
956 }
957 }
6148a742
SF		 958 return open_file;
959 }
960 }
961 read_unlock(&GlobalSMBSeslock);
962 return NULL;
963}
964
1da177e4
LT		 965static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
966{
967 struct address_space *mapping = page->mapping;
968 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
969 char *write_data;
970 int rc = -EFAULT;
971 int bytes_written = 0;
972 struct cifs_sb_info *cifs_sb;
973 struct cifsTconInfo *pTcon;
974 struct inode *inode;
6148a742 975 struct cifsFileInfo *open_file;
1da177e4
LT		 976
977 if (!mapping || !mapping->host)
978 return -EFAULT;
979
980 inode = page->mapping->host;
981 cifs_sb = CIFS_SB(inode->i_sb);
982 pTcon = cifs_sb->tcon;
983
984 offset += (loff_t)from;
985 write_data = kmap(page);
986 write_data += from;
987
988 if ((to > PAGE_CACHE_SIZE) || (from > to)) {
989 kunmap(page);
990 return -EIO;
991 }
992
993 /* racing with truncate? */
994 if (offset > mapping->host->i_size) {
995 kunmap(page);
996 return 0; /* don't care */
997 }
998
999 /* check to make sure that we are not extending the file */
1000 if (mapping->host->i_size - offset < (loff_t)to)
1001 to = (unsigned)(mapping->host->i_size - offset);
1002
6148a742
SF		 1003 open_file = find_writable_file(CIFS_I(mapping->host));
1004 if (open_file) {
1005 bytes_written = cifs_write(open_file->pfile, write_data,
1006 to-from, &offset);
23e7dd7d 1007 atomic_dec(&open_file->wrtPending);
1da177e4 1008 /* Does mm or vfs already set times? */
6148a742
SF		 1009 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1010 if ((bytes_written > 0) && (offset)) {
1011 rc = 0;
1012 } else if (bytes_written < 0) {
1013 if (rc != -EBADF)
1014 rc = bytes_written;
1da177e4 1015 }
6148a742 1016 } else {
1da177e4
LT		 1017 cFYI(1, ("No writeable filehandles for inode"));
1018 rc = -EIO;
1019 }
1020
1021 kunmap(page);
1022 return rc;
1023}
1024
1da177e4 1025static int cifs_writepages(struct address_space *mapping,
37c0eb46 1026 struct writeback_control *wbc)
1da177e4 1027{
37c0eb46
SF		 1028 struct backing_dev_info *bdi = mapping->backing_dev_info;
1029 unsigned int bytes_to_write;
1030 unsigned int bytes_written;
1031 struct cifs_sb_info *cifs_sb;
1032 int done = 0;
1033 pgoff_t end = -1;
1034 pgoff_t index;
1035 int is_range = 0;
1036 struct kvec iov[32];
84d2f07e 1037 int len;
37c0eb46
SF		 1038 int n_iov = 0;
1039 pgoff_t next;
1040 int nr_pages;
1041 __u64 offset = 0;
23e7dd7d 1042 struct cifsFileInfo *open_file;
37c0eb46
SF		 1043 struct page *page;
1044 struct pagevec pvec;
1045 int rc = 0;
1046 int scanned = 0;
1da177e4
LT		 1047 int xid;
1048
37c0eb46
SF		 1049 cifs_sb = CIFS_SB(mapping->host->i_sb);
1050
1051 /*
1052 * If wsize is smaller that the page cache size, default to writing
1053 * one page at a time via cifs_writepage
1054 */
1055 if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1056 return generic_writepages(mapping, wbc);
1057
4a77118c
SF		 1058 /* BB FIXME we do not have code to sign across multiple buffers yet,
1059 so go to older writepage style write which we can sign if needed */
1060 if((cifs_sb->tcon->ses) && (cifs_sb->tcon->ses->server))
1061 if(cifs_sb->tcon->ses->server->secMode &
1062 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
1063 return generic_writepages(mapping, wbc);
1064
37c0eb46
SF		 1065 /*
1066 * BB: Is this meaningful for a non-block-device file system?
1067 * If it is, we should test it again after we do I/O
1068 */
1069 if (wbc->nonblocking && bdi_write_congested(bdi)) {
1070 wbc->encountered_congestion = 1;
1071 return 0;
1072 }
1073
1da177e4
LT		 1074 xid = GetXid();
1075
37c0eb46
SF		 1076 pagevec_init(&pvec, 0);
1077 if (wbc->sync_mode == WB_SYNC_NONE)
1078 index = mapping->writeback_index; /* Start from prev offset */
1079 else {
1080 index = 0;
1081 scanned = 1;
1082 }
1083 if (wbc->start || wbc->end) {
1084 index = wbc->start >> PAGE_CACHE_SHIFT;
1085 end = wbc->end >> PAGE_CACHE_SHIFT;
1086 is_range = 1;
1087 scanned = 1;
1088 }
1089retry:
1090 while (!done && (index <= end) &&
1091 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
1092 PAGECACHE_TAG_DIRTY,
1093 min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
1094 int first;
1095 unsigned int i;
1096
37c0eb46
SF		 1097 first = -1;
1098 next = 0;
1099 n_iov = 0;
1100 bytes_to_write = 0;
1101
1102 for (i = 0; i < nr_pages; i++) {
1103 page = pvec.pages[i];
1104 /*
1105 * At this point we hold neither mapping->tree_lock nor
1106 * lock on the page itself: the page may be truncated or
1107 * invalidated (changing page->mapping to NULL), or even
1108 * swizzled back from swapper_space to tmpfs file
1109 * mapping
1110 */
1111
1112 if (first < 0)
1113 lock_page(page);
1114 else if (TestSetPageLocked(page))
1115 break;
1116
1117 if (unlikely(page->mapping != mapping)) {
1118 unlock_page(page);
1119 break;
1120 }
1121
1122 if (unlikely(is_range) && (page->index > end)) {
1123 done = 1;
1124 unlock_page(page);
1125 break;
1126 }
1127
1128 if (next && (page->index != next)) {
1129 /* Not next consecutive page */
1130 unlock_page(page);
1131 break;
1132 }
1133
1134 if (wbc->sync_mode != WB_SYNC_NONE)
1135 wait_on_page_writeback(page);
1136
1137 if (PageWriteback(page) ||
1138 !test_clear_page_dirty(page)) {
1139 unlock_page(page);
1140 break;
1141 }
84d2f07e
SF		 1142
1143 if (page_offset(page) >= mapping->host->i_size) {
1144 done = 1;
1145 unlock_page(page);
1146 break;
1147 }
1148
37c0eb46
SF		 1149 /*
1150 * BB can we get rid of this? pages are held by pvec
1151 */
1152 page_cache_get(page);
1153
84d2f07e
SF		 1154 len = min(mapping->host->i_size - page_offset(page),
1155 (loff_t)PAGE_CACHE_SIZE);
1156
37c0eb46
SF		 1157 /* reserve iov[0] for the smb header */
1158 n_iov++;
1159 iov[n_iov].iov_base = kmap(page);
84d2f07e
SF		 1160 iov[n_iov].iov_len = len;
1161 bytes_to_write += len;
37c0eb46
SF		 1162
1163 if (first < 0) {
1164 first = i;
1165 offset = page_offset(page);
1166 }
1167 next = page->index + 1;
1168 if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
1169 break;
1170 }
1171 if (n_iov) {
23e7dd7d
SF		 1172 /* Search for a writable handle every time we call
1173 * CIFSSMBWrite2. We can't rely on the last handle
1174 * we used to still be valid
1175 */
1176 open_file = find_writable_file(CIFS_I(mapping->host));
1177 if (!open_file) {
1178 cERROR(1, ("No writable handles for inode"));
1179 rc = -EBADF;
1047abc1 1180 } else {
23e7dd7d
SF		 1181 rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
1182 open_file->netfid,
1183 bytes_to_write, offset,
1184 &bytes_written, iov, n_iov,
1185 1);
1186 atomic_dec(&open_file->wrtPending);
1187 if (rc || bytes_written < bytes_to_write) {
1188 cERROR(1,("Write2 ret %d, written = %d",
1189 rc, bytes_written));
1190 /* BB what if continued retry is
1191 requested via mount flags? */
1192 set_bit(AS_EIO, &mapping->flags);
23e7dd7d
SF		 1193 } else {
1194 cifs_stats_bytes_written(cifs_sb->tcon,
1195 bytes_written);
1196 }
37c0eb46
SF		 1197 }
1198 for (i = 0; i < n_iov; i++) {
1199 page = pvec.pages[first + i];
eb9bdaa3
SF		 1200 /* Should we also set page error on
1201 success rc but too little data written? */
1202 /* BB investigate retry logic on temporary
1203 server crash cases and how recovery works
1204 when page marked as error */
1205 if(rc)
1206 SetPageError(page);
37c0eb46
SF		 1207 kunmap(page);
1208 unlock_page(page);
1209 page_cache_release(page);
1210 }
1211 if ((wbc->nr_to_write -= n_iov) <= 0)
1212 done = 1;
1213 index = next;
1214 }
1215 pagevec_release(&pvec);
1216 }
1217 if (!scanned && !done) {
1218 /*
1219 * We hit the last page and there is more work to be done: wrap
1220 * back to the start of the file
1221 */
1222 scanned = 1;
1223 index = 0;
1224 goto retry;
1225 }
1226 if (!is_range)
1227 mapping->writeback_index = index;
1228
1da177e4 1229 FreeXid(xid);
37c0eb46 1230
1da177e4
LT		 1231 return rc;
1232}
1da177e4
LT		 1233
1234static int cifs_writepage(struct page* page, struct writeback_control *wbc)
1235{
1236 int rc = -EFAULT;
1237 int xid;
1238
1239 xid = GetXid();
1240/* BB add check for wbc flags */
1241 page_cache_get(page);
1242 if (!PageUptodate(page)) {
1243 cFYI(1, ("ppw - page not up to date"));
1244 }
1245
1246 rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1247 SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
1248 unlock_page(page);
1249 page_cache_release(page);
1250 FreeXid(xid);
1251 return rc;
1252}
1253
1254static int cifs_commit_write(struct file *file, struct page *page,
1255 unsigned offset, unsigned to)
1256{
1257 int xid;
1258 int rc = 0;
1259 struct inode *inode = page->mapping->host;
1260 loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
1261 char *page_data;
1262
1263 xid = GetXid();
1264 cFYI(1, ("commit write for page %p up to position %lld for %d",
1265 page, position, to));
1266 if (position > inode->i_size) {
1267 i_size_write(inode, position);
1268 /* if (file->private_data == NULL) {
1269 rc = -EBADF;
1270 } else {
1271 open_file = (struct cifsFileInfo *)file->private_data;
1272 cifs_sb = CIFS_SB(inode->i_sb);
1273 rc = -EAGAIN;
1274 while (rc == -EAGAIN) {
1275 if ((open_file->invalidHandle) &&
1276 (!open_file->closePend)) {
1277 rc = cifs_reopen_file(
1278 file->f_dentry->d_inode, file);
1279 if (rc != 0)
1280 break;
1281 }
1282 if (!open_file->closePend) {
1283 rc = CIFSSMBSetFileSize(xid,
1284 cifs_sb->tcon, position,
1285 open_file->netfid,
1286 open_file->pid, FALSE);
1287 } else {
1288 rc = -EBADF;
1289 break;
1290 }
1291 }
1292 cFYI(1, (" SetEOF (commit write) rc = %d", rc));
1293 } */
1294 }
1295 if (!PageUptodate(page)) {
1296 position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset;
1297 /* can not rely on (or let) writepage write this data */
1298 if (to < offset) {
1299 cFYI(1, ("Illegal offsets, can not copy from %d to %d",
1300 offset, to));
1301 FreeXid(xid);
1302 return rc;
1303 }
1304 /* this is probably better than directly calling
1305 partialpage_write since in this function the file handle is
1306 known which we might as well leverage */
1307 /* BB check if anything else missing out of ppw
1308 such as updating last write time */
1309 page_data = kmap(page);
1310 rc = cifs_write(file, page_data + offset, to-offset,
1311 &position);
1312 if (rc > 0)
1313 rc = 0;
1314 /* else if (rc < 0) should we set writebehind rc? */
1315 kunmap(page);
1316 } else {
1317 set_page_dirty(page);
1318 }
1319
1320 FreeXid(xid);
1321 return rc;
1322}
1323
1324int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
1325{
1326 int xid;
1327 int rc = 0;
1328 struct inode *inode = file->f_dentry->d_inode;
1329
1330 xid = GetXid();
1331
1332 cFYI(1, ("Sync file - name: %s datasync: 0x%x ",
1333 dentry->d_name.name, datasync));
1334
1335 rc = filemap_fdatawrite(inode->i_mapping);
1336 if (rc == 0)
1337 CIFS_I(inode)->write_behind_rc = 0;
1338 FreeXid(xid);
1339 return rc;
1340}
1341
1342/* static int cifs_sync_page(struct page *page)
1343{
1344 struct address_space *mapping;
1345 struct inode *inode;
1346 unsigned long index = page->index;
1347 unsigned int rpages = 0;
1348 int rc = 0;
1349
1350 cFYI(1, ("sync page %p",page));
1351 mapping = page->mapping;
1352 if (!mapping)
1353 return 0;
1354 inode = mapping->host;
1355 if (!inode)
1356 return 0; */
1357
1358/* fill in rpages then
1359 result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
1360
1361/* cFYI(1, ("rpages is %d for sync page of Index %ld ", rpages, index));
1362
1363 if (rc < 0)
1364 return rc;
1365 return 0;
1366} */
1367
1368/*
1369 * As file closes, flush all cached write data for this inode checking
1370 * for write behind errors.
1371 */
1372int cifs_flush(struct file *file)
1373{
1374 struct inode * inode = file->f_dentry->d_inode;
1375 int rc = 0;
1376
1377 /* Rather than do the steps manually:
1378 lock the inode for writing
1379 loop through pages looking for write behind data (dirty pages)
1380 coalesce into contiguous 16K (or smaller) chunks to write to server
1381 send to server (prefer in parallel)
1382 deal with writebehind errors
1383 unlock inode for writing
1384 filemapfdatawrite appears easier for the time being */
1385
1386 rc = filemap_fdatawrite(inode->i_mapping);
1387 if (!rc) /* reset wb rc if we were able to write out dirty pages */
1388 CIFS_I(inode)->write_behind_rc = 0;
1389
1390 cFYI(1, ("Flush inode %p file %p rc %d",inode,file,rc));
1391
1392 return rc;
1393}
1394
1395ssize_t cifs_user_read(struct file *file, char __user *read_data,
1396 size_t read_size, loff_t *poffset)
1397{
1398 int rc = -EACCES;
1399 unsigned int bytes_read = 0;
1400 unsigned int total_read = 0;
1401 unsigned int current_read_size;
1402 struct cifs_sb_info *cifs_sb;
1403 struct cifsTconInfo *pTcon;
1404 int xid;
1405 struct cifsFileInfo *open_file;
1406 char *smb_read_data;
1407 char __user *current_offset;
1408 struct smb_com_read_rsp *pSMBr;
1409
1410 xid = GetXid();
1411 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1412 pTcon = cifs_sb->tcon;
1413
1414 if (file->private_data == NULL) {
1415 FreeXid(xid);
1416 return -EBADF;
1417 }
1418 open_file = (struct cifsFileInfo *)file->private_data;
1419
1420 if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
1421 cFYI(1, ("attempting read on write only file instance"));
1422 }
1423 for (total_read = 0, current_offset = read_data;
1424 read_size > total_read;
1425 total_read += bytes_read, current_offset += bytes_read) {
1426 current_read_size = min_t(const int, read_size - total_read,
1427 cifs_sb->rsize);
1428 rc = -EAGAIN;
1429 smb_read_data = NULL;
1430 while (rc == -EAGAIN) {
ec637e3f 1431 int buf_type = CIFS_NO_BUFFER;
1da177e4
LT		 1432 if ((open_file->invalidHandle) &&
1433 (!open_file->closePend)) {
1434 rc = cifs_reopen_file(file->f_dentry->d_inode,
1435 file, TRUE);
1436 if (rc != 0)
1437 break;
1438 }
bfa0d75a 1439 rc = CIFSSMBRead(xid, pTcon,
ec637e3f
SF		 1440 open_file->netfid,
1441 current_read_size, *poffset,
1442 &bytes_read, &smb_read_data,
1443 &buf_type);
1da177e4
LT		 1444 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1445 if (copy_to_user(current_offset,
1446 smb_read_data + 4 /* RFC1001 hdr */
1447 + le16_to_cpu(pSMBr->DataOffset),
1448 bytes_read)) {
1449 rc = -EFAULT;
ec637e3f 1450 }
1da177e4 1451 if (smb_read_data) {
ec637e3f
SF		 1452 if(buf_type == CIFS_SMALL_BUFFER)
1453 cifs_small_buf_release(smb_read_data);
1454 else if(buf_type == CIFS_LARGE_BUFFER)
1455 cifs_buf_release(smb_read_data);
1da177e4
LT		 1456 smb_read_data = NULL;
1457 }
1458 }
1459 if (rc || (bytes_read == 0)) {
1460 if (total_read) {
1461 break;
1462 } else {
1463 FreeXid(xid);
1464 return rc;
1465 }
1466 } else {
a4544347 1467 cifs_stats_bytes_read(pTcon, bytes_read);
1da177e4
LT		 1468 *poffset += bytes_read;
1469 }
1470 }
1471 FreeXid(xid);
1472 return total_read;
1473}
1474
1475
1476static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
1477 loff_t *poffset)
1478{
1479 int rc = -EACCES;
1480 unsigned int bytes_read = 0;
1481 unsigned int total_read;
1482 unsigned int current_read_size;
1483 struct cifs_sb_info *cifs_sb;
1484 struct cifsTconInfo *pTcon;
1485 int xid;
1486 char *current_offset;
1487 struct cifsFileInfo *open_file;
ec637e3f 1488 int buf_type = CIFS_NO_BUFFER;
1da177e4
LT		 1489
1490 xid = GetXid();
1491 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1492 pTcon = cifs_sb->tcon;
1493
1494 if (file->private_data == NULL) {
1495 FreeXid(xid);
1496 return -EBADF;
1497 }
1498 open_file = (struct cifsFileInfo *)file->private_data;
1499
1500 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1501 cFYI(1, ("attempting read on write only file instance"));
1502
1503 for (total_read = 0, current_offset = read_data;
1504 read_size > total_read;
1505 total_read += bytes_read, current_offset += bytes_read) {
1506 current_read_size = min_t(const int, read_size - total_read,
1507 cifs_sb->rsize);
f9f5c817
SF		 1508 /* For windows me and 9x we do not want to request more
1509 than it negotiated since it will refuse the read then */
1510 if((pTcon->ses) &&
1511 !(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
1512 current_read_size = min_t(const int, current_read_size,
1513 pTcon->ses->server->maxBuf - 128);
1514 }
1da177e4
LT		 1515 rc = -EAGAIN;
1516 while (rc == -EAGAIN) {
1517 if ((open_file->invalidHandle) &&
1518 (!open_file->closePend)) {
1519 rc = cifs_reopen_file(file->f_dentry->d_inode,
1520 file, TRUE);
1521 if (rc != 0)
1522 break;
1523 }
bfa0d75a 1524 rc = CIFSSMBRead(xid, pTcon,
ec637e3f
SF		 1525 open_file->netfid,
1526 current_read_size, *poffset,
1527 &bytes_read, &current_offset,
1528 &buf_type);
1da177e4
LT		 1529 }
1530 if (rc || (bytes_read == 0)) {
1531 if (total_read) {
1532 break;
1533 } else {
1534 FreeXid(xid);
1535 return rc;
1536 }
1537 } else {
a4544347 1538 cifs_stats_bytes_read(pTcon, total_read);
1da177e4
LT		 1539 *poffset += bytes_read;
1540 }
1541 }
1542 FreeXid(xid);
1543 return total_read;
1544}
1545
1546int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
1547{
1548 struct dentry *dentry = file->f_dentry;
1549 int rc, xid;
1550
1551 xid = GetXid();
1552 rc = cifs_revalidate(dentry);
1553 if (rc) {
1554 cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
1555 FreeXid(xid);
1556 return rc;
1557 }
1558 rc = generic_file_mmap(file, vma);
1559 FreeXid(xid);
1560 return rc;
1561}
1562
1563
1564static void cifs_copy_cache_pages(struct address_space *mapping,
1565 struct list_head *pages, int bytes_read, char *data,
1566 struct pagevec *plru_pvec)
1567{
1568 struct page *page;
1569 char *target;
1570
1571 while (bytes_read > 0) {
1572 if (list_empty(pages))
1573 break;
1574
1575 page = list_entry(pages->prev, struct page, lru);
1576 list_del(&page->lru);
1577
1578 if (add_to_page_cache(page, mapping, page->index,
1579 GFP_KERNEL)) {
1580 page_cache_release(page);
1581 cFYI(1, ("Add page cache failed"));
3079ca62
SF		 1582 data += PAGE_CACHE_SIZE;
1583 bytes_read -= PAGE_CACHE_SIZE;
1da177e4
LT		 1584 continue;
1585 }
1586
1587 target = kmap_atomic(page,KM_USER0);
1588
1589 if (PAGE_CACHE_SIZE > bytes_read) {
1590 memcpy(target, data, bytes_read);
1591 /* zero the tail end of this partial page */
1592 memset(target + bytes_read, 0,
1593 PAGE_CACHE_SIZE - bytes_read);
1594 bytes_read = 0;
1595 } else {
1596 memcpy(target, data, PAGE_CACHE_SIZE);
1597 bytes_read -= PAGE_CACHE_SIZE;
1598 }
1599 kunmap_atomic(target, KM_USER0);
1600
1601 flush_dcache_page(page);
1602 SetPageUptodate(page);
1603 unlock_page(page);
1604 if (!pagevec_add(plru_pvec, page))
1605 __pagevec_lru_add(plru_pvec);
1606 data += PAGE_CACHE_SIZE;
1607 }
1608 return;
1609}
1610
1611static int cifs_readpages(struct file *file, struct address_space *mapping,
1612 struct list_head *page_list, unsigned num_pages)
1613{
1614 int rc = -EACCES;
1615 int xid;
1616 loff_t offset;
1617 struct page *page;
1618 struct cifs_sb_info *cifs_sb;
1619 struct cifsTconInfo *pTcon;
1620 int bytes_read = 0;
1621 unsigned int read_size,i;
1622 char *smb_read_data = NULL;
1623 struct smb_com_read_rsp *pSMBr;
1624 struct pagevec lru_pvec;
1625 struct cifsFileInfo *open_file;
ec637e3f 1626 int buf_type = CIFS_NO_BUFFER;
1da177e4
LT		 1627
1628 xid = GetXid();
1629 if (file->private_data == NULL) {
1630 FreeXid(xid);
1631 return -EBADF;
1632 }
1633 open_file = (struct cifsFileInfo *)file->private_data;
1634 cifs_sb = CIFS_SB(file->f_dentry->d_sb);
1635 pTcon = cifs_sb->tcon;
bfa0d75a 1636
1da177e4
LT		 1637 pagevec_init(&lru_pvec, 0);
1638
1639 for (i = 0; i < num_pages; ) {
1640 unsigned contig_pages;
1641 struct page *tmp_page;
1642 unsigned long expected_index;
1643
1644 if (list_empty(page_list))
1645 break;
1646
1647 page = list_entry(page_list->prev, struct page, lru);
1648 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1649
1650 /* count adjacent pages that we will read into */
1651 contig_pages = 0;
1652 expected_index =
1653 list_entry(page_list->prev, struct page, lru)->index;
1654 list_for_each_entry_reverse(tmp_page,page_list,lru) {
1655 if (tmp_page->index == expected_index) {
1656 contig_pages++;
1657 expected_index++;
1658 } else
1659 break;
1660 }
1661 if (contig_pages + i > num_pages)
1662 contig_pages = num_pages - i;
1663
1664 /* for reads over a certain size could initiate async
1665 read ahead */
1666
1667 read_size = contig_pages * PAGE_CACHE_SIZE;
1668 /* Read size needs to be in multiples of one page */
1669 read_size = min_t(const unsigned int, read_size,
1670 cifs_sb->rsize & PAGE_CACHE_MASK);
1671
1672 rc = -EAGAIN;
1673 while (rc == -EAGAIN) {
1674 if ((open_file->invalidHandle) &&
1675 (!open_file->closePend)) {
1676 rc = cifs_reopen_file(file->f_dentry->d_inode,
1677 file, TRUE);
1678 if (rc != 0)
1679 break;
1680 }
1681
bfa0d75a 1682 rc = CIFSSMBRead(xid, pTcon,
ec637e3f
SF		 1683 open_file->netfid,
1684 read_size, offset,
1685 &bytes_read, &smb_read_data,
1686 &buf_type);
a9d02ad4 1687 /* BB more RC checks ? */
1da177e4
LT		 1688 if (rc== -EAGAIN) {
1689 if (smb_read_data) {
ec637e3f
SF		 1690 if(buf_type == CIFS_SMALL_BUFFER)
1691 cifs_small_buf_release(smb_read_data);
1692 else if(buf_type == CIFS_LARGE_BUFFER)
1693 cifs_buf_release(smb_read_data);
1da177e4
LT		 1694 smb_read_data = NULL;
1695 }
1696 }
1697 }
1698 if ((rc < 0) || (smb_read_data == NULL)) {
1699 cFYI(1, ("Read error in readpages: %d", rc));
1700 /* clean up remaing pages off list */
1701 while (!list_empty(page_list) && (i < num_pages)) {
1702 page = list_entry(page_list->prev, struct page,
1703 lru);
1704 list_del(&page->lru);
1705 page_cache_release(page);
1706 }
1707 break;
1708 } else if (bytes_read > 0) {
1709 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1710 cifs_copy_cache_pages(mapping, page_list, bytes_read,
1711 smb_read_data + 4 /* RFC1001 hdr */ +
1712 le16_to_cpu(pSMBr->DataOffset), &lru_pvec);
1713
1714 i += bytes_read >> PAGE_CACHE_SHIFT;
a4544347 1715 cifs_stats_bytes_read(pTcon, bytes_read);
1da177e4
LT		 1716 if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
1717 i++; /* account for partial page */
1718
1719 /* server copy of file can have smaller size
1720 than client */
1721 /* BB do we need to verify this common case ?
1722 this case is ok - if we are at server EOF
1723 we will hit it on next read */
1724
1725 /* while (!list_empty(page_list) && (i < num_pages)) {
1726 page = list_entry(page_list->prev,
1727 struct page, list);
1728 list_del(&page->list);
1729 page_cache_release(page);
1730 }
1731 break; */
1732 }
1733 } else {
1734 cFYI(1, ("No bytes read (%d) at offset %lld . "
1735 "Cleaning remaining pages from readahead list",
1736 bytes_read, offset));
1737 /* BB turn off caching and do new lookup on
1738 file size at server? */
1739 while (!list_empty(page_list) && (i < num_pages)) {
1740 page = list_entry(page_list->prev, struct page,
1741 lru);
1742 list_del(&page->lru);
1743
1744 /* BB removeme - replace with zero of page? */
1745 page_cache_release(page);
1746 }
1747 break;
1748 }
1749 if (smb_read_data) {
ec637e3f
SF		 1750 if(buf_type == CIFS_SMALL_BUFFER)
1751 cifs_small_buf_release(smb_read_data);
1752 else if(buf_type == CIFS_LARGE_BUFFER)
1753 cifs_buf_release(smb_read_data);
1da177e4
LT		 1754 smb_read_data = NULL;
1755 }
1756 bytes_read = 0;
1757 }
1758
1759 pagevec_lru_add(&lru_pvec);
1760
1761/* need to free smb_read_data buf before exit */
1762 if (smb_read_data) {
47c886b3
SF		 1763 if(buf_type == CIFS_SMALL_BUFFER)
1764 cifs_small_buf_release(smb_read_data);
1765 else if(buf_type == CIFS_LARGE_BUFFER)
1766 cifs_buf_release(smb_read_data);
1da177e4
LT		 1767 smb_read_data = NULL;
1768 }
1769
1770 FreeXid(xid);
1771 return rc;
1772}
1773
1774static int cifs_readpage_worker(struct file *file, struct page *page,
1775 loff_t *poffset)
1776{
1777 char *read_data;
1778 int rc;
1779
1780 page_cache_get(page);
1781 read_data = kmap(page);
1782 /* for reads over a certain size could initiate async read ahead */
1783
1784 rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
1785
1786 if (rc < 0)
1787 goto io_error;
1788 else
1789 cFYI(1, ("Bytes read %d ",rc));
1790
1791 file->f_dentry->d_inode->i_atime =
1792 current_fs_time(file->f_dentry->d_inode->i_sb);
1793
1794 if (PAGE_CACHE_SIZE > rc)
1795 memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
1796
1797 flush_dcache_page(page);
1798 SetPageUptodate(page);
1799 rc = 0;
1800
1801io_error:
1802 kunmap(page);
1803 page_cache_release(page);
1804 return rc;
1805}
1806
1807static int cifs_readpage(struct file *file, struct page *page)
1808{
1809 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1810 int rc = -EACCES;
1811 int xid;
1812
1813 xid = GetXid();
1814
1815 if (file->private_data == NULL) {
1816 FreeXid(xid);
1817 return -EBADF;
1818 }
1819
1820 cFYI(1, ("readpage %p at offset %d 0x%x\n",
1821 page, (int)offset, (int)offset));
1822
1823 rc = cifs_readpage_worker(file, page, &offset);
1824
1825 unlock_page(page);
1826
1827 FreeXid(xid);
1828 return rc;
1829}
1830
1831/* We do not want to update the file size from server for inodes
1832 open for write - to avoid races with writepage extending
1833 the file - in the future we could consider allowing
1834 refreshing the inode only on increases in the file size
1835 but this is tricky to do without racing with writebehind
1836 page caching in the current Linux kernel design */
1837int is_size_safe_to_change(struct cifsInodeInfo *cifsInode)
1838{
23e7dd7d
SF		 1839 struct cifsFileInfo *open_file = NULL;
1840
1841 if (cifsInode)
1842 open_file = find_writable_file(cifsInode);
1843
1844 if(open_file) {
c32a0b68
SF		 1845 struct cifs_sb_info *cifs_sb;
1846
23e7dd7d
SF		 1847 /* there is not actually a write pending so let
1848 this handle go free and allow it to
1849 be closable if needed */
1850 atomic_dec(&open_file->wrtPending);
c32a0b68
SF		 1851
1852 cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
1853 if ( cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO ) {
1854 /* since no page cache to corrupt on directio
1855 we can change size safely */
1856 return 1;
1857 }
1858
6148a742 1859 return 0;
23e7dd7d 1860 } else
6148a742 1861 return 1;
1da177e4
LT		 1862}
1863
1da177e4
LT		 1864static int cifs_prepare_write(struct file *file, struct page *page,
1865 unsigned from, unsigned to)
1866{
1867 int rc = 0;
1868 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1869 cFYI(1, ("prepare write for page %p from %d to %d",page,from,to));
1870 if (!PageUptodate(page)) {
1871 /* if (to - from != PAGE_CACHE_SIZE) {
1872 void *kaddr = kmap_atomic(page, KM_USER0);
1873 memset(kaddr, 0, from);
1874 memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
1875 flush_dcache_page(page);
1876 kunmap_atomic(kaddr, KM_USER0);
1877 } */
1878 /* If we are writing a full page it will be up to date,
1879 no need to read from the server */
1880 if ((to == PAGE_CACHE_SIZE) && (from == 0))
1881 SetPageUptodate(page);
1882
1883 /* might as well read a page, it is fast enough */
1884 if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
1885 rc = cifs_readpage_worker(file, page, &offset);
1886 } else {
1887 /* should we try using another file handle if there is one -
1888 how would we lock it to prevent close of that handle
1889 racing with this read?
1890 In any case this will be written out by commit_write */
1891 }
1892 }
1893
1894 /* BB should we pass any errors back?
1895 e.g. if we do not have read access to the file */
1896 return 0;
1897}
1898
1899struct address_space_operations cifs_addr_ops = {
1900 .readpage = cifs_readpage,
1901 .readpages = cifs_readpages,
1902 .writepage = cifs_writepage,
37c0eb46 1903 .writepages = cifs_writepages,
1da177e4
LT		 1904 .prepare_write = cifs_prepare_write,
1905 .commit_write = cifs_commit_write,
1906 .set_page_dirty = __set_page_dirty_nobuffers,
1907 /* .sync_page = cifs_sync_page, */
1908 /* .direct_IO = */
1909};
Linux 6.x block layer and io_uring tree(s)