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Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
[mirror_ubuntu-bionic-kernel.git] / fs / cifs / file.c
1 /*
2 * fs/cifs/file.c
3 *
4 * vfs operations that deal with files
5 *
6 * Copyright (C) International Business Machines Corp., 2002,2003
7 * Author(s): Steve French (sfrench@us.ibm.com)
8 * Jeremy Allison (jra@samba.org)
9 *
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.
14 *
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.
19 *
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
23 */
24 #include <linux/fs.h>
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/smp_lock.h>
31 #include <linux/writeback.h>
32 #include <linux/task_io_accounting_ops.h>
33 #include <linux/delay.h>
34 #include <asm/div64.h>
35 #include "cifsfs.h"
36 #include "cifspdu.h"
37 #include "cifsglob.h"
38 #include "cifsproto.h"
39 #include "cifs_unicode.h"
40 #include "cifs_debug.h"
41 #include "cifs_fs_sb.h"
42
43 static inline struct cifsFileInfo *cifs_init_private(
44 struct cifsFileInfo *private_data, struct inode *inode,
45 struct file *file, __u16 netfid)
46 {
47 memset(private_data, 0, sizeof(struct cifsFileInfo));
48 private_data->netfid = netfid;
49 private_data->pid = current->tgid;
50 init_MUTEX(&private_data->fh_sem);
51 mutex_init(&private_data->lock_mutex);
52 INIT_LIST_HEAD(&private_data->llist);
53 private_data->pfile = file; /* needed for writepage */
54 private_data->pInode = inode;
55 private_data->invalidHandle = FALSE;
56 private_data->closePend = FALSE;
57 /* we have to track num writers to the inode, since writepages
58 does not tell us which handle the write is for so there can
59 be a close (overlapping with write) of the filehandle that
60 cifs_writepages chose to use */
61 atomic_set(&private_data->wrtPending,0);
62
63 return private_data;
64 }
65
66 static inline int cifs_convert_flags(unsigned int flags)
67 {
68 if ((flags & O_ACCMODE) == O_RDONLY)
69 return GENERIC_READ;
70 else if ((flags & O_ACCMODE) == O_WRONLY)
71 return GENERIC_WRITE;
72 else if ((flags & O_ACCMODE) == O_RDWR) {
73 /* GENERIC_ALL is too much permission to request
74 can cause unnecessary access denied on create */
75 /* return GENERIC_ALL; */
76 return (GENERIC_READ | GENERIC_WRITE);
77 }
78
79 return 0x20197;
80 }
81
82 static inline int cifs_get_disposition(unsigned int flags)
83 {
84 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
85 return FILE_CREATE;
86 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
87 return FILE_OVERWRITE_IF;
88 else if ((flags & O_CREAT) == O_CREAT)
89 return FILE_OPEN_IF;
90 else if ((flags & O_TRUNC) == O_TRUNC)
91 return FILE_OVERWRITE;
92 else
93 return FILE_OPEN;
94 }
95
96 /* all arguments to this function must be checked for validity in caller */
97 static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
98 struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile,
99 struct cifsTconInfo *pTcon, int *oplock, FILE_ALL_INFO *buf,
100 char *full_path, int xid)
101 {
102 struct timespec temp;
103 int rc;
104
105 /* want handles we can use to read with first
106 in the list so we do not have to walk the
107 list to search for one in prepare_write */
108 if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
109 list_add_tail(&pCifsFile->flist,
110 &pCifsInode->openFileList);
111 } else {
112 list_add(&pCifsFile->flist,
113 &pCifsInode->openFileList);
114 }
115 write_unlock(&GlobalSMBSeslock);
116 if (pCifsInode->clientCanCacheRead) {
117 /* we have the inode open somewhere else
118 no need to discard cache data */
119 goto client_can_cache;
120 }
121
122 /* BB need same check in cifs_create too? */
123 /* if not oplocked, invalidate inode pages if mtime or file
124 size changed */
125 temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime));
126 if (timespec_equal(&file->f_path.dentry->d_inode->i_mtime, &temp) &&
127 (file->f_path.dentry->d_inode->i_size ==
128 (loff_t)le64_to_cpu(buf->EndOfFile))) {
129 cFYI(1, ("inode unchanged on server"));
130 } else {
131 if (file->f_path.dentry->d_inode->i_mapping) {
132 /* BB no need to lock inode until after invalidate
133 since namei code should already have it locked? */
134 filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping);
135 }
136 cFYI(1, ("invalidating remote inode since open detected it "
137 "changed"));
138 invalidate_remote_inode(file->f_path.dentry->d_inode);
139 }
140
141 client_can_cache:
142 if (pTcon->ses->capabilities & CAP_UNIX)
143 rc = cifs_get_inode_info_unix(&file->f_path.dentry->d_inode,
144 full_path, inode->i_sb, xid);
145 else
146 rc = cifs_get_inode_info(&file->f_path.dentry->d_inode,
147 full_path, buf, inode->i_sb, xid);
148
149 if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) {
150 pCifsInode->clientCanCacheAll = TRUE;
151 pCifsInode->clientCanCacheRead = TRUE;
152 cFYI(1, ("Exclusive Oplock granted on inode %p",
153 file->f_path.dentry->d_inode));
154 } else if ((*oplock & 0xF) == OPLOCK_READ)
155 pCifsInode->clientCanCacheRead = TRUE;
156
157 return rc;
158 }
159
160 int cifs_open(struct inode *inode, struct file *file)
161 {
162 int rc = -EACCES;
163 int xid, oplock;
164 struct cifs_sb_info *cifs_sb;
165 struct cifsTconInfo *pTcon;
166 struct cifsFileInfo *pCifsFile;
167 struct cifsInodeInfo *pCifsInode;
168 struct list_head *tmp;
169 char *full_path = NULL;
170 int desiredAccess;
171 int disposition;
172 __u16 netfid;
173 FILE_ALL_INFO *buf = NULL;
174
175 xid = GetXid();
176
177 cifs_sb = CIFS_SB(inode->i_sb);
178 pTcon = cifs_sb->tcon;
179
180 if (file->f_flags & O_CREAT) {
181 /* search inode for this file and fill in file->private_data */
182 pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
183 read_lock(&GlobalSMBSeslock);
184 list_for_each(tmp, &pCifsInode->openFileList) {
185 pCifsFile = list_entry(tmp, struct cifsFileInfo,
186 flist);
187 if ((pCifsFile->pfile == NULL) &&
188 (pCifsFile->pid == current->tgid)) {
189 /* mode set in cifs_create */
190
191 /* needed for writepage */
192 pCifsFile->pfile = file;
193
194 file->private_data = pCifsFile;
195 break;
196 }
197 }
198 read_unlock(&GlobalSMBSeslock);
199 if (file->private_data != NULL) {
200 rc = 0;
201 FreeXid(xid);
202 return rc;
203 } else {
204 if (file->f_flags & O_EXCL)
205 cERROR(1, ("could not find file instance for "
206 "new file %p", file));
207 }
208 }
209
210 full_path = build_path_from_dentry(file->f_path.dentry);
211 if (full_path == NULL) {
212 FreeXid(xid);
213 return -ENOMEM;
214 }
215
216 cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
217 inode, file->f_flags, full_path));
218 desiredAccess = cifs_convert_flags(file->f_flags);
219
220 /*********************************************************************
221 * open flag mapping table:
222 *
223 * POSIX Flag CIFS Disposition
224 * ---------- ----------------
225 * O_CREAT FILE_OPEN_IF
226 * O_CREAT | O_EXCL FILE_CREATE
227 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
228 * O_TRUNC FILE_OVERWRITE
229 * none of the above FILE_OPEN
230 *
231 * Note that there is not a direct match between disposition
232 * FILE_SUPERSEDE (ie create whether or not file exists although
233 * O_CREAT | O_TRUNC is similar but truncates the existing
234 * file rather than creating a new file as FILE_SUPERSEDE does
235 * (which uses the attributes / metadata passed in on open call)
236 *?
237 *? O_SYNC is a reasonable match to CIFS writethrough flag
238 *? and the read write flags match reasonably. O_LARGEFILE
239 *? is irrelevant because largefile support is always used
240 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
241 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
242 *********************************************************************/
243
244 disposition = cifs_get_disposition(file->f_flags);
245
246 if (oplockEnabled)
247 oplock = REQ_OPLOCK;
248 else
249 oplock = FALSE;
250
251 /* BB pass O_SYNC flag through on file attributes .. BB */
252
253 /* Also refresh inode by passing in file_info buf returned by SMBOpen
254 and calling get_inode_info with returned buf (at least helps
255 non-Unix server case) */
256
257 /* BB we can not do this if this is the second open of a file
258 and the first handle has writebehind data, we might be
259 able to simply do a filemap_fdatawrite/filemap_fdatawait first */
260 buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
261 if (!buf) {
262 rc = -ENOMEM;
263 goto out;
264 }
265
266 if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS)
267 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition,
268 desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
269 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
270 & CIFS_MOUNT_MAP_SPECIAL_CHR);
271 else
272 rc = -EIO; /* no NT SMB support fall into legacy open below */
273
274 if (rc == -EIO) {
275 /* Old server, try legacy style OpenX */
276 rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
277 desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
278 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
279 & CIFS_MOUNT_MAP_SPECIAL_CHR);
280 }
281 if (rc) {
282 cFYI(1, ("cifs_open returned 0x%x", rc));
283 goto out;
284 }
285 file->private_data =
286 kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
287 if (file->private_data == NULL) {
288 rc = -ENOMEM;
289 goto out;
290 }
291 pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
292 write_lock(&GlobalSMBSeslock);
293 list_add(&pCifsFile->tlist, &pTcon->openFileList);
294
295 pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
296 if (pCifsInode) {
297 rc = cifs_open_inode_helper(inode, file, pCifsInode,
298 pCifsFile, pTcon,
299 &oplock, buf, full_path, xid);
300 } else {
301 write_unlock(&GlobalSMBSeslock);
302 }
303
304 if (oplock & CIFS_CREATE_ACTION) {
305 /* time to set mode which we can not set earlier due to
306 problems creating new read-only files */
307 if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
308 CIFSSMBUnixSetPerms(xid, pTcon, full_path,
309 inode->i_mode,
310 (__u64)-1, (__u64)-1, 0 /* dev */,
311 cifs_sb->local_nls,
312 cifs_sb->mnt_cifs_flags &
313 CIFS_MOUNT_MAP_SPECIAL_CHR);
314 } else {
315 /* BB implement via Windows security descriptors eg
316 CIFSSMBWinSetPerms(xid, pTcon, full_path, mode,
317 -1, -1, local_nls);
318 in the meantime could set r/o dos attribute when
319 perms are eg: mode & 0222 == 0 */
320 }
321 }
322
323 out:
324 kfree(buf);
325 kfree(full_path);
326 FreeXid(xid);
327 return rc;
328 }
329
330 /* Try to reacquire byte range locks that were released when session */
331 /* to server was lost */
332 static int cifs_relock_file(struct cifsFileInfo *cifsFile)
333 {
334 int rc = 0;
335
336 /* BB list all locks open on this file and relock */
337
338 return rc;
339 }
340
341 static int cifs_reopen_file(struct file *file, int can_flush)
342 {
343 int rc = -EACCES;
344 int xid, oplock;
345 struct cifs_sb_info *cifs_sb;
346 struct cifsTconInfo *pTcon;
347 struct cifsFileInfo *pCifsFile;
348 struct cifsInodeInfo *pCifsInode;
349 struct inode * inode;
350 char *full_path = NULL;
351 int desiredAccess;
352 int disposition = FILE_OPEN;
353 __u16 netfid;
354
355 if (file->private_data) {
356 pCifsFile = (struct cifsFileInfo *)file->private_data;
357 } else
358 return -EBADF;
359
360 xid = GetXid();
361 down(&pCifsFile->fh_sem);
362 if (pCifsFile->invalidHandle == FALSE) {
363 up(&pCifsFile->fh_sem);
364 FreeXid(xid);
365 return 0;
366 }
367
368 if (file->f_path.dentry == NULL) {
369 cERROR(1, ("no valid name if dentry freed"));
370 dump_stack();
371 rc = -EBADF;
372 goto reopen_error_exit;
373 }
374
375 inode = file->f_path.dentry->d_inode;
376 if(inode == NULL) {
377 cERROR(1, ("inode not valid"));
378 dump_stack();
379 rc = -EBADF;
380 goto reopen_error_exit;
381 }
382
383 cifs_sb = CIFS_SB(inode->i_sb);
384 pTcon = cifs_sb->tcon;
385
386 /* can not grab rename sem here because various ops, including
387 those that already have the rename sem can end up causing writepage
388 to get called and if the server was down that means we end up here,
389 and we can never tell if the caller already has the rename_sem */
390 full_path = build_path_from_dentry(file->f_path.dentry);
391 if (full_path == NULL) {
392 rc = -ENOMEM;
393 reopen_error_exit:
394 up(&pCifsFile->fh_sem);
395 FreeXid(xid);
396 return rc;
397 }
398
399 cFYI(1, ("inode = 0x%p file flags 0x%x for %s",
400 inode, file->f_flags,full_path));
401 desiredAccess = cifs_convert_flags(file->f_flags);
402
403 if (oplockEnabled)
404 oplock = REQ_OPLOCK;
405 else
406 oplock = FALSE;
407
408 /* Can not refresh inode by passing in file_info buf to be returned
409 by SMBOpen and then calling get_inode_info with returned buf
410 since file might have write behind data that needs to be flushed
411 and server version of file size can be stale. If we knew for sure
412 that inode was not dirty locally we could do this */
413
414 rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
415 CREATE_NOT_DIR, &netfid, &oplock, NULL,
416 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
417 CIFS_MOUNT_MAP_SPECIAL_CHR);
418 if (rc) {
419 up(&pCifsFile->fh_sem);
420 cFYI(1, ("cifs_open returned 0x%x", rc));
421 cFYI(1, ("oplock: %d", oplock));
422 } else {
423 pCifsFile->netfid = netfid;
424 pCifsFile->invalidHandle = FALSE;
425 up(&pCifsFile->fh_sem);
426 pCifsInode = CIFS_I(inode);
427 if (pCifsInode) {
428 if (can_flush) {
429 filemap_write_and_wait(inode->i_mapping);
430 /* temporarily disable caching while we
431 go to server to get inode info */
432 pCifsInode->clientCanCacheAll = FALSE;
433 pCifsInode->clientCanCacheRead = FALSE;
434 if (pTcon->ses->capabilities & CAP_UNIX)
435 rc = cifs_get_inode_info_unix(&inode,
436 full_path, inode->i_sb, xid);
437 else
438 rc = cifs_get_inode_info(&inode,
439 full_path, NULL, inode->i_sb,
440 xid);
441 } /* else we are writing out data to server already
442 and could deadlock if we tried to flush data, and
443 since we do not know if we have data that would
444 invalidate the current end of file on the server
445 we can not go to the server to get the new inod
446 info */
447 if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
448 pCifsInode->clientCanCacheAll = TRUE;
449 pCifsInode->clientCanCacheRead = TRUE;
450 cFYI(1, ("Exclusive Oplock granted on inode %p",
451 file->f_path.dentry->d_inode));
452 } else if ((oplock & 0xF) == OPLOCK_READ) {
453 pCifsInode->clientCanCacheRead = TRUE;
454 pCifsInode->clientCanCacheAll = FALSE;
455 } else {
456 pCifsInode->clientCanCacheRead = FALSE;
457 pCifsInode->clientCanCacheAll = FALSE;
458 }
459 cifs_relock_file(pCifsFile);
460 }
461 }
462
463 kfree(full_path);
464 FreeXid(xid);
465 return rc;
466 }
467
468 int cifs_close(struct inode *inode, struct file *file)
469 {
470 int rc = 0;
471 int xid;
472 struct cifs_sb_info *cifs_sb;
473 struct cifsTconInfo *pTcon;
474 struct cifsFileInfo *pSMBFile =
475 (struct cifsFileInfo *)file->private_data;
476
477 xid = GetXid();
478
479 cifs_sb = CIFS_SB(inode->i_sb);
480 pTcon = cifs_sb->tcon;
481 if (pSMBFile) {
482 struct cifsLockInfo *li, *tmp;
483
484 pSMBFile->closePend = TRUE;
485 if (pTcon) {
486 /* no sense reconnecting to close a file that is
487 already closed */
488 if (pTcon->tidStatus != CifsNeedReconnect) {
489 int timeout = 2;
490 while((atomic_read(&pSMBFile->wrtPending) != 0)
491 && (timeout < 1000) ) {
492 /* Give write a better chance to get to
493 server ahead of the close. We do not
494 want to add a wait_q here as it would
495 increase the memory utilization as
496 the struct would be in each open file,
497 but this should give enough time to
498 clear the socket */
499 #ifdef CONFIG_CIFS_DEBUG2
500 cFYI(1,("close delay, write pending"));
501 #endif /* DEBUG2 */
502 msleep(timeout);
503 timeout *= 4;
504 }
505 if(atomic_read(&pSMBFile->wrtPending))
506 cERROR(1,("close with pending writes"));
507 rc = CIFSSMBClose(xid, pTcon,
508 pSMBFile->netfid);
509 }
510 }
511
512 /* Delete any outstanding lock records.
513 We'll lose them when the file is closed anyway. */
514 mutex_lock(&pSMBFile->lock_mutex);
515 list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) {
516 list_del(&li->llist);
517 kfree(li);
518 }
519 mutex_unlock(&pSMBFile->lock_mutex);
520
521 write_lock(&GlobalSMBSeslock);
522 list_del(&pSMBFile->flist);
523 list_del(&pSMBFile->tlist);
524 write_unlock(&GlobalSMBSeslock);
525 kfree(pSMBFile->search_resume_name);
526 kfree(file->private_data);
527 file->private_data = NULL;
528 } else
529 rc = -EBADF;
530
531 if (list_empty(&(CIFS_I(inode)->openFileList))) {
532 cFYI(1, ("closing last open instance for inode %p", inode));
533 /* if the file is not open we do not know if we can cache info
534 on this inode, much less write behind and read ahead */
535 CIFS_I(inode)->clientCanCacheRead = FALSE;
536 CIFS_I(inode)->clientCanCacheAll = FALSE;
537 }
538 if ((rc ==0) && CIFS_I(inode)->write_behind_rc)
539 rc = CIFS_I(inode)->write_behind_rc;
540 FreeXid(xid);
541 return rc;
542 }
543
544 int cifs_closedir(struct inode *inode, struct file *file)
545 {
546 int rc = 0;
547 int xid;
548 struct cifsFileInfo *pCFileStruct =
549 (struct cifsFileInfo *)file->private_data;
550 char *ptmp;
551
552 cFYI(1, ("Closedir inode = 0x%p", inode));
553
554 xid = GetXid();
555
556 if (pCFileStruct) {
557 struct cifsTconInfo *pTcon;
558 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
559
560 pTcon = cifs_sb->tcon;
561
562 cFYI(1, ("Freeing private data in close dir"));
563 if ((pCFileStruct->srch_inf.endOfSearch == FALSE) &&
564 (pCFileStruct->invalidHandle == FALSE)) {
565 pCFileStruct->invalidHandle = TRUE;
566 rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
567 cFYI(1, ("Closing uncompleted readdir with rc %d",
568 rc));
569 /* not much we can do if it fails anyway, ignore rc */
570 rc = 0;
571 }
572 ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
573 if (ptmp) {
574 cFYI(1, ("closedir free smb buf in srch struct"));
575 pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
576 if(pCFileStruct->srch_inf.smallBuf)
577 cifs_small_buf_release(ptmp);
578 else
579 cifs_buf_release(ptmp);
580 }
581 ptmp = pCFileStruct->search_resume_name;
582 if (ptmp) {
583 cFYI(1, ("closedir free resume name"));
584 pCFileStruct->search_resume_name = NULL;
585 kfree(ptmp);
586 }
587 kfree(file->private_data);
588 file->private_data = NULL;
589 }
590 /* BB can we lock the filestruct while this is going on? */
591 FreeXid(xid);
592 return rc;
593 }
594
595 static int store_file_lock(struct cifsFileInfo *fid, __u64 len,
596 __u64 offset, __u8 lockType)
597 {
598 struct cifsLockInfo *li = kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
599 if (li == NULL)
600 return -ENOMEM;
601 li->offset = offset;
602 li->length = len;
603 li->type = lockType;
604 mutex_lock(&fid->lock_mutex);
605 list_add(&li->llist, &fid->llist);
606 mutex_unlock(&fid->lock_mutex);
607 return 0;
608 }
609
610 int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
611 {
612 int rc, xid;
613 __u32 numLock = 0;
614 __u32 numUnlock = 0;
615 __u64 length;
616 int wait_flag = FALSE;
617 struct cifs_sb_info *cifs_sb;
618 struct cifsTconInfo *pTcon;
619 __u16 netfid;
620 __u8 lockType = LOCKING_ANDX_LARGE_FILES;
621 int posix_locking;
622
623 length = 1 + pfLock->fl_end - pfLock->fl_start;
624 rc = -EACCES;
625 xid = GetXid();
626
627 cFYI(1, ("Lock parm: 0x%x flockflags: "
628 "0x%x flocktype: 0x%x start: %lld end: %lld",
629 cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
630 pfLock->fl_end));
631
632 if (pfLock->fl_flags & FL_POSIX)
633 cFYI(1, ("Posix"));
634 if (pfLock->fl_flags & FL_FLOCK)
635 cFYI(1, ("Flock"));
636 if (pfLock->fl_flags & FL_SLEEP) {
637 cFYI(1, ("Blocking lock"));
638 wait_flag = TRUE;
639 }
640 if (pfLock->fl_flags & FL_ACCESS)
641 cFYI(1, ("Process suspended by mandatory locking - "
642 "not implemented yet"));
643 if (pfLock->fl_flags & FL_LEASE)
644 cFYI(1, ("Lease on file - not implemented yet"));
645 if (pfLock->fl_flags &
646 (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
647 cFYI(1, ("Unknown lock flags 0x%x", pfLock->fl_flags));
648
649 if (pfLock->fl_type == F_WRLCK) {
650 cFYI(1, ("F_WRLCK "));
651 numLock = 1;
652 } else if (pfLock->fl_type == F_UNLCK) {
653 cFYI(1, ("F_UNLCK"));
654 numUnlock = 1;
655 /* Check if unlock includes more than
656 one lock range */
657 } else if (pfLock->fl_type == F_RDLCK) {
658 cFYI(1, ("F_RDLCK"));
659 lockType |= LOCKING_ANDX_SHARED_LOCK;
660 numLock = 1;
661 } else if (pfLock->fl_type == F_EXLCK) {
662 cFYI(1, ("F_EXLCK"));
663 numLock = 1;
664 } else if (pfLock->fl_type == F_SHLCK) {
665 cFYI(1, ("F_SHLCK"));
666 lockType |= LOCKING_ANDX_SHARED_LOCK;
667 numLock = 1;
668 } else
669 cFYI(1, ("Unknown type of lock"));
670
671 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
672 pTcon = cifs_sb->tcon;
673
674 if (file->private_data == NULL) {
675 FreeXid(xid);
676 return -EBADF;
677 }
678 netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
679
680 posix_locking = (cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
681 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability));
682
683 /* BB add code here to normalize offset and length to
684 account for negative length which we can not accept over the
685 wire */
686 if (IS_GETLK(cmd)) {
687 if(posix_locking) {
688 int posix_lock_type;
689 if(lockType & LOCKING_ANDX_SHARED_LOCK)
690 posix_lock_type = CIFS_RDLCK;
691 else
692 posix_lock_type = CIFS_WRLCK;
693 rc = CIFSSMBPosixLock(xid, pTcon, netfid, 1 /* get */,
694 length, pfLock,
695 posix_lock_type, wait_flag);
696 FreeXid(xid);
697 return rc;
698 }
699
700 /* BB we could chain these into one lock request BB */
701 rc = CIFSSMBLock(xid, pTcon, netfid, length, pfLock->fl_start,
702 0, 1, lockType, 0 /* wait flag */ );
703 if (rc == 0) {
704 rc = CIFSSMBLock(xid, pTcon, netfid, length,
705 pfLock->fl_start, 1 /* numUnlock */ ,
706 0 /* numLock */ , lockType,
707 0 /* wait flag */ );
708 pfLock->fl_type = F_UNLCK;
709 if (rc != 0)
710 cERROR(1, ("Error unlocking previously locked "
711 "range %d during test of lock", rc));
712 rc = 0;
713
714 } else {
715 /* if rc == ERR_SHARING_VIOLATION ? */
716 rc = 0; /* do not change lock type to unlock
717 since range in use */
718 }
719
720 FreeXid(xid);
721 return rc;
722 }
723
724 if (!numLock && !numUnlock) {
725 /* if no lock or unlock then nothing
726 to do since we do not know what it is */
727 FreeXid(xid);
728 return -EOPNOTSUPP;
729 }
730
731 if (posix_locking) {
732 int posix_lock_type;
733 if(lockType & LOCKING_ANDX_SHARED_LOCK)
734 posix_lock_type = CIFS_RDLCK;
735 else
736 posix_lock_type = CIFS_WRLCK;
737
738 if(numUnlock == 1)
739 posix_lock_type = CIFS_UNLCK;
740
741 rc = CIFSSMBPosixLock(xid, pTcon, netfid, 0 /* set */,
742 length, pfLock,
743 posix_lock_type, wait_flag);
744 } else {
745 struct cifsFileInfo *fid = (struct cifsFileInfo *)file->private_data;
746
747 if (numLock) {
748 rc = CIFSSMBLock(xid, pTcon, netfid, length, pfLock->fl_start,
749 0, numLock, lockType, wait_flag);
750
751 if (rc == 0) {
752 /* For Windows locks we must store them. */
753 rc = store_file_lock(fid, length,
754 pfLock->fl_start, lockType);
755 }
756 } else if (numUnlock) {
757 /* For each stored lock that this unlock overlaps
758 completely, unlock it. */
759 int stored_rc = 0;
760 struct cifsLockInfo *li, *tmp;
761
762 rc = 0;
763 mutex_lock(&fid->lock_mutex);
764 list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
765 if (pfLock->fl_start <= li->offset &&
766 length >= li->length) {
767 stored_rc = CIFSSMBLock(xid, pTcon, netfid,
768 li->length, li->offset,
769 1, 0, li->type, FALSE);
770 if (stored_rc)
771 rc = stored_rc;
772
773 list_del(&li->llist);
774 kfree(li);
775 }
776 }
777 mutex_unlock(&fid->lock_mutex);
778 }
779 }
780
781 if (pfLock->fl_flags & FL_POSIX)
782 posix_lock_file_wait(file, pfLock);
783 FreeXid(xid);
784 return rc;
785 }
786
787 ssize_t cifs_user_write(struct file *file, const char __user *write_data,
788 size_t write_size, loff_t *poffset)
789 {
790 int rc = 0;
791 unsigned int bytes_written = 0;
792 unsigned int total_written;
793 struct cifs_sb_info *cifs_sb;
794 struct cifsTconInfo *pTcon;
795 int xid, long_op;
796 struct cifsFileInfo *open_file;
797
798 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
799
800 pTcon = cifs_sb->tcon;
801
802 /* cFYI(1,
803 (" write %d bytes to offset %lld of %s", write_size,
804 *poffset, file->f_path.dentry->d_name.name)); */
805
806 if (file->private_data == NULL)
807 return -EBADF;
808 open_file = (struct cifsFileInfo *) file->private_data;
809
810 xid = GetXid();
811
812 if (*poffset > file->f_path.dentry->d_inode->i_size)
813 long_op = 2; /* writes past end of file can take a long time */
814 else
815 long_op = 1;
816
817 for (total_written = 0; write_size > total_written;
818 total_written += bytes_written) {
819 rc = -EAGAIN;
820 while (rc == -EAGAIN) {
821 if (file->private_data == NULL) {
822 /* file has been closed on us */
823 FreeXid(xid);
824 /* if we have gotten here we have written some data
825 and blocked, and the file has been freed on us while
826 we blocked so return what we managed to write */
827 return total_written;
828 }
829 if (open_file->closePend) {
830 FreeXid(xid);
831 if (total_written)
832 return total_written;
833 else
834 return -EBADF;
835 }
836 if (open_file->invalidHandle) {
837 /* we could deadlock if we called
838 filemap_fdatawait from here so tell
839 reopen_file not to flush data to server
840 now */
841 rc = cifs_reopen_file(file, FALSE);
842 if (rc != 0)
843 break;
844 }
845
846 rc = CIFSSMBWrite(xid, pTcon,
847 open_file->netfid,
848 min_t(const int, cifs_sb->wsize,
849 write_size - total_written),
850 *poffset, &bytes_written,
851 NULL, write_data + total_written, long_op);
852 }
853 if (rc || (bytes_written == 0)) {
854 if (total_written)
855 break;
856 else {
857 FreeXid(xid);
858 return rc;
859 }
860 } else
861 *poffset += bytes_written;
862 long_op = FALSE; /* subsequent writes fast -
863 15 seconds is plenty */
864 }
865
866 cifs_stats_bytes_written(pTcon, total_written);
867
868 /* since the write may have blocked check these pointers again */
869 if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
870 struct inode *inode = file->f_path.dentry->d_inode;
871 /* Do not update local mtime - server will set its actual value on write
872 * inode->i_ctime = inode->i_mtime =
873 * current_fs_time(inode->i_sb);*/
874 if (total_written > 0) {
875 spin_lock(&inode->i_lock);
876 if (*poffset > file->f_path.dentry->d_inode->i_size)
877 i_size_write(file->f_path.dentry->d_inode,
878 *poffset);
879 spin_unlock(&inode->i_lock);
880 }
881 mark_inode_dirty_sync(file->f_path.dentry->d_inode);
882 }
883 FreeXid(xid);
884 return total_written;
885 }
886
887 static ssize_t cifs_write(struct file *file, const char *write_data,
888 size_t write_size, loff_t *poffset)
889 {
890 int rc = 0;
891 unsigned int bytes_written = 0;
892 unsigned int total_written;
893 struct cifs_sb_info *cifs_sb;
894 struct cifsTconInfo *pTcon;
895 int xid, long_op;
896 struct cifsFileInfo *open_file;
897
898 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
899
900 pTcon = cifs_sb->tcon;
901
902 cFYI(1,("write %zd bytes to offset %lld of %s", write_size,
903 *poffset, file->f_path.dentry->d_name.name));
904
905 if (file->private_data == NULL)
906 return -EBADF;
907 open_file = (struct cifsFileInfo *)file->private_data;
908
909 xid = GetXid();
910
911 if (*poffset > file->f_path.dentry->d_inode->i_size)
912 long_op = 2; /* writes past end of file can take a long time */
913 else
914 long_op = 1;
915
916 for (total_written = 0; write_size > total_written;
917 total_written += bytes_written) {
918 rc = -EAGAIN;
919 while (rc == -EAGAIN) {
920 if (file->private_data == NULL) {
921 /* file has been closed on us */
922 FreeXid(xid);
923 /* if we have gotten here we have written some data
924 and blocked, and the file has been freed on us
925 while we blocked so return what we managed to
926 write */
927 return total_written;
928 }
929 if (open_file->closePend) {
930 FreeXid(xid);
931 if (total_written)
932 return total_written;
933 else
934 return -EBADF;
935 }
936 if (open_file->invalidHandle) {
937 /* we could deadlock if we called
938 filemap_fdatawait from here so tell
939 reopen_file not to flush data to
940 server now */
941 rc = cifs_reopen_file(file, FALSE);
942 if (rc != 0)
943 break;
944 }
945 if(experimEnabled || (pTcon->ses->server &&
946 ((pTcon->ses->server->secMode &
947 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
948 == 0))) {
949 struct kvec iov[2];
950 unsigned int len;
951
952 len = min((size_t)cifs_sb->wsize,
953 write_size - total_written);
954 /* iov[0] is reserved for smb header */
955 iov[1].iov_base = (char *)write_data +
956 total_written;
957 iov[1].iov_len = len;
958 rc = CIFSSMBWrite2(xid, pTcon,
959 open_file->netfid, len,
960 *poffset, &bytes_written,
961 iov, 1, long_op);
962 } else
963 rc = CIFSSMBWrite(xid, pTcon,
964 open_file->netfid,
965 min_t(const int, cifs_sb->wsize,
966 write_size - total_written),
967 *poffset, &bytes_written,
968 write_data + total_written,
969 NULL, long_op);
970 }
971 if (rc || (bytes_written == 0)) {
972 if (total_written)
973 break;
974 else {
975 FreeXid(xid);
976 return rc;
977 }
978 } else
979 *poffset += bytes_written;
980 long_op = FALSE; /* subsequent writes fast -
981 15 seconds is plenty */
982 }
983
984 cifs_stats_bytes_written(pTcon, total_written);
985
986 /* since the write may have blocked check these pointers again */
987 if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
988 /*BB We could make this contingent on superblock ATIME flag too */
989 /* file->f_path.dentry->d_inode->i_ctime =
990 file->f_path.dentry->d_inode->i_mtime = CURRENT_TIME;*/
991 if (total_written > 0) {
992 spin_lock(&file->f_path.dentry->d_inode->i_lock);
993 if (*poffset > file->f_path.dentry->d_inode->i_size)
994 i_size_write(file->f_path.dentry->d_inode,
995 *poffset);
996 spin_unlock(&file->f_path.dentry->d_inode->i_lock);
997 }
998 mark_inode_dirty_sync(file->f_path.dentry->d_inode);
999 }
1000 FreeXid(xid);
1001 return total_written;
1002 }
1003
1004 struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
1005 {
1006 struct cifsFileInfo *open_file;
1007 int rc;
1008
1009 /* Having a null inode here (because mapping->host was set to zero by
1010 the VFS or MM) should not happen but we had reports of on oops (due to
1011 it being zero) during stress testcases so we need to check for it */
1012
1013 if(cifs_inode == NULL) {
1014 cERROR(1,("Null inode passed to cifs_writeable_file"));
1015 dump_stack();
1016 return NULL;
1017 }
1018
1019 read_lock(&GlobalSMBSeslock);
1020 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1021 if (open_file->closePend)
1022 continue;
1023 if (open_file->pfile &&
1024 ((open_file->pfile->f_flags & O_RDWR) ||
1025 (open_file->pfile->f_flags & O_WRONLY))) {
1026 atomic_inc(&open_file->wrtPending);
1027 read_unlock(&GlobalSMBSeslock);
1028 if((open_file->invalidHandle) &&
1029 (!open_file->closePend) /* BB fixme -since the second clause can not be true remove it BB */) {
1030 rc = cifs_reopen_file(open_file->pfile, FALSE);
1031 /* if it fails, try another handle - might be */
1032 /* dangerous to hold up writepages with retry */
1033 if(rc) {
1034 cFYI(1,("failed on reopen file in wp"));
1035 read_lock(&GlobalSMBSeslock);
1036 /* can not use this handle, no write
1037 pending on this one after all */
1038 atomic_dec
1039 (&open_file->wrtPending);
1040 continue;
1041 }
1042 }
1043 return open_file;
1044 }
1045 }
1046 read_unlock(&GlobalSMBSeslock);
1047 return NULL;
1048 }
1049
1050 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
1051 {
1052 struct address_space *mapping = page->mapping;
1053 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1054 char *write_data;
1055 int rc = -EFAULT;
1056 int bytes_written = 0;
1057 struct cifs_sb_info *cifs_sb;
1058 struct cifsTconInfo *pTcon;
1059 struct inode *inode;
1060 struct cifsFileInfo *open_file;
1061
1062 if (!mapping || !mapping->host)
1063 return -EFAULT;
1064
1065 inode = page->mapping->host;
1066 cifs_sb = CIFS_SB(inode->i_sb);
1067 pTcon = cifs_sb->tcon;
1068
1069 offset += (loff_t)from;
1070 write_data = kmap(page);
1071 write_data += from;
1072
1073 if ((to > PAGE_CACHE_SIZE) || (from > to)) {
1074 kunmap(page);
1075 return -EIO;
1076 }
1077
1078 /* racing with truncate? */
1079 if (offset > mapping->host->i_size) {
1080 kunmap(page);
1081 return 0; /* don't care */
1082 }
1083
1084 /* check to make sure that we are not extending the file */
1085 if (mapping->host->i_size - offset < (loff_t)to)
1086 to = (unsigned)(mapping->host->i_size - offset);
1087
1088 open_file = find_writable_file(CIFS_I(mapping->host));
1089 if (open_file) {
1090 bytes_written = cifs_write(open_file->pfile, write_data,
1091 to-from, &offset);
1092 atomic_dec(&open_file->wrtPending);
1093 /* Does mm or vfs already set times? */
1094 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1095 if ((bytes_written > 0) && (offset)) {
1096 rc = 0;
1097 } else if (bytes_written < 0) {
1098 if (rc != -EBADF)
1099 rc = bytes_written;
1100 }
1101 } else {
1102 cFYI(1, ("No writeable filehandles for inode"));
1103 rc = -EIO;
1104 }
1105
1106 kunmap(page);
1107 return rc;
1108 }
1109
1110 static int cifs_writepages(struct address_space *mapping,
1111 struct writeback_control *wbc)
1112 {
1113 struct backing_dev_info *bdi = mapping->backing_dev_info;
1114 unsigned int bytes_to_write;
1115 unsigned int bytes_written;
1116 struct cifs_sb_info *cifs_sb;
1117 int done = 0;
1118 pgoff_t end;
1119 pgoff_t index;
1120 int range_whole = 0;
1121 struct kvec * iov;
1122 int len;
1123 int n_iov = 0;
1124 pgoff_t next;
1125 int nr_pages;
1126 __u64 offset = 0;
1127 struct cifsFileInfo *open_file;
1128 struct page *page;
1129 struct pagevec pvec;
1130 int rc = 0;
1131 int scanned = 0;
1132 int xid;
1133
1134 cifs_sb = CIFS_SB(mapping->host->i_sb);
1135
1136 /*
1137 * If wsize is smaller that the page cache size, default to writing
1138 * one page at a time via cifs_writepage
1139 */
1140 if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1141 return generic_writepages(mapping, wbc);
1142
1143 if((cifs_sb->tcon->ses) && (cifs_sb->tcon->ses->server))
1144 if(cifs_sb->tcon->ses->server->secMode &
1145 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
1146 if(!experimEnabled)
1147 return generic_writepages(mapping, wbc);
1148
1149 iov = kmalloc(32 * sizeof(struct kvec), GFP_KERNEL);
1150 if(iov == NULL)
1151 return generic_writepages(mapping, wbc);
1152
1153
1154 /*
1155 * BB: Is this meaningful for a non-block-device file system?
1156 * If it is, we should test it again after we do I/O
1157 */
1158 if (wbc->nonblocking && bdi_write_congested(bdi)) {
1159 wbc->encountered_congestion = 1;
1160 kfree(iov);
1161 return 0;
1162 }
1163
1164 xid = GetXid();
1165
1166 pagevec_init(&pvec, 0);
1167 if (wbc->range_cyclic) {
1168 index = mapping->writeback_index; /* Start from prev offset */
1169 end = -1;
1170 } else {
1171 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1172 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1173 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1174 range_whole = 1;
1175 scanned = 1;
1176 }
1177 retry:
1178 while (!done && (index <= end) &&
1179 (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
1180 PAGECACHE_TAG_DIRTY,
1181 min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
1182 int first;
1183 unsigned int i;
1184
1185 first = -1;
1186 next = 0;
1187 n_iov = 0;
1188 bytes_to_write = 0;
1189
1190 for (i = 0; i < nr_pages; i++) {
1191 page = pvec.pages[i];
1192 /*
1193 * At this point we hold neither mapping->tree_lock nor
1194 * lock on the page itself: the page may be truncated or
1195 * invalidated (changing page->mapping to NULL), or even
1196 * swizzled back from swapper_space to tmpfs file
1197 * mapping
1198 */
1199
1200 if (first < 0)
1201 lock_page(page);
1202 else if (TestSetPageLocked(page))
1203 break;
1204
1205 if (unlikely(page->mapping != mapping)) {
1206 unlock_page(page);
1207 break;
1208 }
1209
1210 if (!wbc->range_cyclic && page->index > end) {
1211 done = 1;
1212 unlock_page(page);
1213 break;
1214 }
1215
1216 if (next && (page->index != next)) {
1217 /* Not next consecutive page */
1218 unlock_page(page);
1219 break;
1220 }
1221
1222 if (wbc->sync_mode != WB_SYNC_NONE)
1223 wait_on_page_writeback(page);
1224
1225 if (PageWriteback(page) ||
1226 !clear_page_dirty_for_io(page)) {
1227 unlock_page(page);
1228 break;
1229 }
1230
1231 /*
1232 * This actually clears the dirty bit in the radix tree.
1233 * See cifs_writepage() for more commentary.
1234 */
1235 set_page_writeback(page);
1236
1237 if (page_offset(page) >= mapping->host->i_size) {
1238 done = 1;
1239 unlock_page(page);
1240 end_page_writeback(page);
1241 break;
1242 }
1243
1244 /*
1245 * BB can we get rid of this? pages are held by pvec
1246 */
1247 page_cache_get(page);
1248
1249 len = min(mapping->host->i_size - page_offset(page),
1250 (loff_t)PAGE_CACHE_SIZE);
1251
1252 /* reserve iov[0] for the smb header */
1253 n_iov++;
1254 iov[n_iov].iov_base = kmap(page);
1255 iov[n_iov].iov_len = len;
1256 bytes_to_write += len;
1257
1258 if (first < 0) {
1259 first = i;
1260 offset = page_offset(page);
1261 }
1262 next = page->index + 1;
1263 if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
1264 break;
1265 }
1266 if (n_iov) {
1267 /* Search for a writable handle every time we call
1268 * CIFSSMBWrite2. We can't rely on the last handle
1269 * we used to still be valid
1270 */
1271 open_file = find_writable_file(CIFS_I(mapping->host));
1272 if (!open_file) {
1273 cERROR(1, ("No writable handles for inode"));
1274 rc = -EBADF;
1275 } else {
1276 rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
1277 open_file->netfid,
1278 bytes_to_write, offset,
1279 &bytes_written, iov, n_iov,
1280 1);
1281 atomic_dec(&open_file->wrtPending);
1282 if (rc || bytes_written < bytes_to_write) {
1283 cERROR(1,("Write2 ret %d, written = %d",
1284 rc, bytes_written));
1285 /* BB what if continued retry is
1286 requested via mount flags? */
1287 set_bit(AS_EIO, &mapping->flags);
1288 } else {
1289 cifs_stats_bytes_written(cifs_sb->tcon,
1290 bytes_written);
1291 }
1292 }
1293 for (i = 0; i < n_iov; i++) {
1294 page = pvec.pages[first + i];
1295 /* Should we also set page error on
1296 success rc but too little data written? */
1297 /* BB investigate retry logic on temporary
1298 server crash cases and how recovery works
1299 when page marked as error */
1300 if(rc)
1301 SetPageError(page);
1302 kunmap(page);
1303 unlock_page(page);
1304 end_page_writeback(page);
1305 page_cache_release(page);
1306 }
1307 if ((wbc->nr_to_write -= n_iov) <= 0)
1308 done = 1;
1309 index = next;
1310 }
1311 pagevec_release(&pvec);
1312 }
1313 if (!scanned && !done) {
1314 /*
1315 * We hit the last page and there is more work to be done: wrap
1316 * back to the start of the file
1317 */
1318 scanned = 1;
1319 index = 0;
1320 goto retry;
1321 }
1322 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1323 mapping->writeback_index = index;
1324
1325 FreeXid(xid);
1326 kfree(iov);
1327 return rc;
1328 }
1329
1330 static int cifs_writepage(struct page* page, struct writeback_control *wbc)
1331 {
1332 int rc = -EFAULT;
1333 int xid;
1334
1335 xid = GetXid();
1336 /* BB add check for wbc flags */
1337 page_cache_get(page);
1338 if (!PageUptodate(page)) {
1339 cFYI(1, ("ppw - page not up to date"));
1340 }
1341
1342 /*
1343 * Set the "writeback" flag, and clear "dirty" in the radix tree.
1344 *
1345 * A writepage() implementation always needs to do either this,
1346 * or re-dirty the page with "redirty_page_for_writepage()" in
1347 * the case of a failure.
1348 *
1349 * Just unlocking the page will cause the radix tree tag-bits
1350 * to fail to update with the state of the page correctly.
1351 */
1352 set_page_writeback(page);
1353 rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1354 SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
1355 unlock_page(page);
1356 end_page_writeback(page);
1357 page_cache_release(page);
1358 FreeXid(xid);
1359 return rc;
1360 }
1361
1362 static int cifs_commit_write(struct file *file, struct page *page,
1363 unsigned offset, unsigned to)
1364 {
1365 int xid;
1366 int rc = 0;
1367 struct inode *inode = page->mapping->host;
1368 loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
1369 char *page_data;
1370
1371 xid = GetXid();
1372 cFYI(1, ("commit write for page %p up to position %lld for %d",
1373 page, position, to));
1374 spin_lock(&inode->i_lock);
1375 if (position > inode->i_size) {
1376 i_size_write(inode, position);
1377 }
1378 spin_unlock(&inode->i_lock);
1379 if (!PageUptodate(page)) {
1380 position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset;
1381 /* can not rely on (or let) writepage write this data */
1382 if (to < offset) {
1383 cFYI(1, ("Illegal offsets, can not copy from %d to %d",
1384 offset, to));
1385 FreeXid(xid);
1386 return rc;
1387 }
1388 /* this is probably better than directly calling
1389 partialpage_write since in this function the file handle is
1390 known which we might as well leverage */
1391 /* BB check if anything else missing out of ppw
1392 such as updating last write time */
1393 page_data = kmap(page);
1394 rc = cifs_write(file, page_data + offset, to-offset,
1395 &position);
1396 if (rc > 0)
1397 rc = 0;
1398 /* else if (rc < 0) should we set writebehind rc? */
1399 kunmap(page);
1400 } else {
1401 set_page_dirty(page);
1402 }
1403
1404 FreeXid(xid);
1405 return rc;
1406 }
1407
1408 int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
1409 {
1410 int xid;
1411 int rc = 0;
1412 struct inode *inode = file->f_path.dentry->d_inode;
1413
1414 xid = GetXid();
1415
1416 cFYI(1, ("Sync file - name: %s datasync: 0x%x",
1417 dentry->d_name.name, datasync));
1418
1419 rc = filemap_fdatawrite(inode->i_mapping);
1420 if (rc == 0)
1421 CIFS_I(inode)->write_behind_rc = 0;
1422 FreeXid(xid);
1423 return rc;
1424 }
1425
1426 /* static void cifs_sync_page(struct page *page)
1427 {
1428 struct address_space *mapping;
1429 struct inode *inode;
1430 unsigned long index = page->index;
1431 unsigned int rpages = 0;
1432 int rc = 0;
1433
1434 cFYI(1, ("sync page %p",page));
1435 mapping = page->mapping;
1436 if (!mapping)
1437 return 0;
1438 inode = mapping->host;
1439 if (!inode)
1440 return; */
1441
1442 /* fill in rpages then
1443 result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
1444
1445 /* cFYI(1, ("rpages is %d for sync page of Index %ld", rpages, index));
1446
1447 #if 0
1448 if (rc < 0)
1449 return rc;
1450 return 0;
1451 #endif
1452 } */
1453
1454 /*
1455 * As file closes, flush all cached write data for this inode checking
1456 * for write behind errors.
1457 */
1458 int cifs_flush(struct file *file, fl_owner_t id)
1459 {
1460 struct inode * inode = file->f_path.dentry->d_inode;
1461 int rc = 0;
1462
1463 /* Rather than do the steps manually:
1464 lock the inode for writing
1465 loop through pages looking for write behind data (dirty pages)
1466 coalesce into contiguous 16K (or smaller) chunks to write to server
1467 send to server (prefer in parallel)
1468 deal with writebehind errors
1469 unlock inode for writing
1470 filemapfdatawrite appears easier for the time being */
1471
1472 rc = filemap_fdatawrite(inode->i_mapping);
1473 if (!rc) /* reset wb rc if we were able to write out dirty pages */
1474 CIFS_I(inode)->write_behind_rc = 0;
1475
1476 cFYI(1, ("Flush inode %p file %p rc %d",inode,file,rc));
1477
1478 return rc;
1479 }
1480
1481 ssize_t cifs_user_read(struct file *file, char __user *read_data,
1482 size_t read_size, loff_t *poffset)
1483 {
1484 int rc = -EACCES;
1485 unsigned int bytes_read = 0;
1486 unsigned int total_read = 0;
1487 unsigned int current_read_size;
1488 struct cifs_sb_info *cifs_sb;
1489 struct cifsTconInfo *pTcon;
1490 int xid;
1491 struct cifsFileInfo *open_file;
1492 char *smb_read_data;
1493 char __user *current_offset;
1494 struct smb_com_read_rsp *pSMBr;
1495
1496 xid = GetXid();
1497 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1498 pTcon = cifs_sb->tcon;
1499
1500 if (file->private_data == NULL) {
1501 FreeXid(xid);
1502 return -EBADF;
1503 }
1504 open_file = (struct cifsFileInfo *)file->private_data;
1505
1506 if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
1507 cFYI(1, ("attempting read on write only file instance"));
1508 }
1509 for (total_read = 0, current_offset = read_data;
1510 read_size > total_read;
1511 total_read += bytes_read, current_offset += bytes_read) {
1512 current_read_size = min_t(const int, read_size - total_read,
1513 cifs_sb->rsize);
1514 rc = -EAGAIN;
1515 smb_read_data = NULL;
1516 while (rc == -EAGAIN) {
1517 int buf_type = CIFS_NO_BUFFER;
1518 if ((open_file->invalidHandle) &&
1519 (!open_file->closePend)) {
1520 rc = cifs_reopen_file(file, TRUE);
1521 if (rc != 0)
1522 break;
1523 }
1524 rc = CIFSSMBRead(xid, pTcon,
1525 open_file->netfid,
1526 current_read_size, *poffset,
1527 &bytes_read, &smb_read_data,
1528 &buf_type);
1529 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1530 if (smb_read_data) {
1531 if (copy_to_user(current_offset,
1532 smb_read_data +
1533 4 /* RFC1001 length field */ +
1534 le16_to_cpu(pSMBr->DataOffset),
1535 bytes_read)) {
1536 rc = -EFAULT;
1537 }
1538
1539 if(buf_type == CIFS_SMALL_BUFFER)
1540 cifs_small_buf_release(smb_read_data);
1541 else if(buf_type == CIFS_LARGE_BUFFER)
1542 cifs_buf_release(smb_read_data);
1543 smb_read_data = NULL;
1544 }
1545 }
1546 if (rc || (bytes_read == 0)) {
1547 if (total_read) {
1548 break;
1549 } else {
1550 FreeXid(xid);
1551 return rc;
1552 }
1553 } else {
1554 cifs_stats_bytes_read(pTcon, bytes_read);
1555 *poffset += bytes_read;
1556 }
1557 }
1558 FreeXid(xid);
1559 return total_read;
1560 }
1561
1562
1563 static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
1564 loff_t *poffset)
1565 {
1566 int rc = -EACCES;
1567 unsigned int bytes_read = 0;
1568 unsigned int total_read;
1569 unsigned int current_read_size;
1570 struct cifs_sb_info *cifs_sb;
1571 struct cifsTconInfo *pTcon;
1572 int xid;
1573 char *current_offset;
1574 struct cifsFileInfo *open_file;
1575 int buf_type = CIFS_NO_BUFFER;
1576
1577 xid = GetXid();
1578 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1579 pTcon = cifs_sb->tcon;
1580
1581 if (file->private_data == NULL) {
1582 FreeXid(xid);
1583 return -EBADF;
1584 }
1585 open_file = (struct cifsFileInfo *)file->private_data;
1586
1587 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1588 cFYI(1, ("attempting read on write only file instance"));
1589
1590 for (total_read = 0, current_offset = read_data;
1591 read_size > total_read;
1592 total_read += bytes_read, current_offset += bytes_read) {
1593 current_read_size = min_t(const int, read_size - total_read,
1594 cifs_sb->rsize);
1595 /* For windows me and 9x we do not want to request more
1596 than it negotiated since it will refuse the read then */
1597 if((pTcon->ses) &&
1598 !(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
1599 current_read_size = min_t(const int, current_read_size,
1600 pTcon->ses->server->maxBuf - 128);
1601 }
1602 rc = -EAGAIN;
1603 while (rc == -EAGAIN) {
1604 if ((open_file->invalidHandle) &&
1605 (!open_file->closePend)) {
1606 rc = cifs_reopen_file(file, TRUE);
1607 if (rc != 0)
1608 break;
1609 }
1610 rc = CIFSSMBRead(xid, pTcon,
1611 open_file->netfid,
1612 current_read_size, *poffset,
1613 &bytes_read, &current_offset,
1614 &buf_type);
1615 }
1616 if (rc || (bytes_read == 0)) {
1617 if (total_read) {
1618 break;
1619 } else {
1620 FreeXid(xid);
1621 return rc;
1622 }
1623 } else {
1624 cifs_stats_bytes_read(pTcon, total_read);
1625 *poffset += bytes_read;
1626 }
1627 }
1628 FreeXid(xid);
1629 return total_read;
1630 }
1631
1632 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
1633 {
1634 struct dentry *dentry = file->f_path.dentry;
1635 int rc, xid;
1636
1637 xid = GetXid();
1638 rc = cifs_revalidate(dentry);
1639 if (rc) {
1640 cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
1641 FreeXid(xid);
1642 return rc;
1643 }
1644 rc = generic_file_mmap(file, vma);
1645 FreeXid(xid);
1646 return rc;
1647 }
1648
1649
1650 static void cifs_copy_cache_pages(struct address_space *mapping,
1651 struct list_head *pages, int bytes_read, char *data,
1652 struct pagevec *plru_pvec)
1653 {
1654 struct page *page;
1655 char *target;
1656
1657 while (bytes_read > 0) {
1658 if (list_empty(pages))
1659 break;
1660
1661 page = list_entry(pages->prev, struct page, lru);
1662 list_del(&page->lru);
1663
1664 if (add_to_page_cache(page, mapping, page->index,
1665 GFP_KERNEL)) {
1666 page_cache_release(page);
1667 cFYI(1, ("Add page cache failed"));
1668 data += PAGE_CACHE_SIZE;
1669 bytes_read -= PAGE_CACHE_SIZE;
1670 continue;
1671 }
1672
1673 target = kmap_atomic(page,KM_USER0);
1674
1675 if (PAGE_CACHE_SIZE > bytes_read) {
1676 memcpy(target, data, bytes_read);
1677 /* zero the tail end of this partial page */
1678 memset(target + bytes_read, 0,
1679 PAGE_CACHE_SIZE - bytes_read);
1680 bytes_read = 0;
1681 } else {
1682 memcpy(target, data, PAGE_CACHE_SIZE);
1683 bytes_read -= PAGE_CACHE_SIZE;
1684 }
1685 kunmap_atomic(target, KM_USER0);
1686
1687 flush_dcache_page(page);
1688 SetPageUptodate(page);
1689 unlock_page(page);
1690 if (!pagevec_add(plru_pvec, page))
1691 __pagevec_lru_add(plru_pvec);
1692 data += PAGE_CACHE_SIZE;
1693 }
1694 return;
1695 }
1696
1697 static int cifs_readpages(struct file *file, struct address_space *mapping,
1698 struct list_head *page_list, unsigned num_pages)
1699 {
1700 int rc = -EACCES;
1701 int xid;
1702 loff_t offset;
1703 struct page *page;
1704 struct cifs_sb_info *cifs_sb;
1705 struct cifsTconInfo *pTcon;
1706 int bytes_read = 0;
1707 unsigned int read_size,i;
1708 char *smb_read_data = NULL;
1709 struct smb_com_read_rsp *pSMBr;
1710 struct pagevec lru_pvec;
1711 struct cifsFileInfo *open_file;
1712 int buf_type = CIFS_NO_BUFFER;
1713
1714 xid = GetXid();
1715 if (file->private_data == NULL) {
1716 FreeXid(xid);
1717 return -EBADF;
1718 }
1719 open_file = (struct cifsFileInfo *)file->private_data;
1720 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1721 pTcon = cifs_sb->tcon;
1722
1723 pagevec_init(&lru_pvec, 0);
1724
1725 for (i = 0; i < num_pages; ) {
1726 unsigned contig_pages;
1727 struct page *tmp_page;
1728 unsigned long expected_index;
1729
1730 if (list_empty(page_list))
1731 break;
1732
1733 page = list_entry(page_list->prev, struct page, lru);
1734 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1735
1736 /* count adjacent pages that we will read into */
1737 contig_pages = 0;
1738 expected_index =
1739 list_entry(page_list->prev, struct page, lru)->index;
1740 list_for_each_entry_reverse(tmp_page,page_list,lru) {
1741 if (tmp_page->index == expected_index) {
1742 contig_pages++;
1743 expected_index++;
1744 } else
1745 break;
1746 }
1747 if (contig_pages + i > num_pages)
1748 contig_pages = num_pages - i;
1749
1750 /* for reads over a certain size could initiate async
1751 read ahead */
1752
1753 read_size = contig_pages * PAGE_CACHE_SIZE;
1754 /* Read size needs to be in multiples of one page */
1755 read_size = min_t(const unsigned int, read_size,
1756 cifs_sb->rsize & PAGE_CACHE_MASK);
1757
1758 rc = -EAGAIN;
1759 while (rc == -EAGAIN) {
1760 if ((open_file->invalidHandle) &&
1761 (!open_file->closePend)) {
1762 rc = cifs_reopen_file(file, TRUE);
1763 if (rc != 0)
1764 break;
1765 }
1766
1767 rc = CIFSSMBRead(xid, pTcon,
1768 open_file->netfid,
1769 read_size, offset,
1770 &bytes_read, &smb_read_data,
1771 &buf_type);
1772 /* BB more RC checks ? */
1773 if (rc== -EAGAIN) {
1774 if (smb_read_data) {
1775 if(buf_type == CIFS_SMALL_BUFFER)
1776 cifs_small_buf_release(smb_read_data);
1777 else if(buf_type == CIFS_LARGE_BUFFER)
1778 cifs_buf_release(smb_read_data);
1779 smb_read_data = NULL;
1780 }
1781 }
1782 }
1783 if ((rc < 0) || (smb_read_data == NULL)) {
1784 cFYI(1, ("Read error in readpages: %d", rc));
1785 break;
1786 } else if (bytes_read > 0) {
1787 task_io_account_read(bytes_read);
1788 pSMBr = (struct smb_com_read_rsp *)smb_read_data;
1789 cifs_copy_cache_pages(mapping, page_list, bytes_read,
1790 smb_read_data + 4 /* RFC1001 hdr */ +
1791 le16_to_cpu(pSMBr->DataOffset), &lru_pvec);
1792
1793 i += bytes_read >> PAGE_CACHE_SHIFT;
1794 cifs_stats_bytes_read(pTcon, bytes_read);
1795 if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
1796 i++; /* account for partial page */
1797
1798 /* server copy of file can have smaller size
1799 than client */
1800 /* BB do we need to verify this common case ?
1801 this case is ok - if we are at server EOF
1802 we will hit it on next read */
1803
1804 /* break; */
1805 }
1806 } else {
1807 cFYI(1, ("No bytes read (%d) at offset %lld . "
1808 "Cleaning remaining pages from readahead list",
1809 bytes_read, offset));
1810 /* BB turn off caching and do new lookup on
1811 file size at server? */
1812 break;
1813 }
1814 if (smb_read_data) {
1815 if(buf_type == CIFS_SMALL_BUFFER)
1816 cifs_small_buf_release(smb_read_data);
1817 else if(buf_type == CIFS_LARGE_BUFFER)
1818 cifs_buf_release(smb_read_data);
1819 smb_read_data = NULL;
1820 }
1821 bytes_read = 0;
1822 }
1823
1824 pagevec_lru_add(&lru_pvec);
1825
1826 /* need to free smb_read_data buf before exit */
1827 if (smb_read_data) {
1828 if(buf_type == CIFS_SMALL_BUFFER)
1829 cifs_small_buf_release(smb_read_data);
1830 else if(buf_type == CIFS_LARGE_BUFFER)
1831 cifs_buf_release(smb_read_data);
1832 smb_read_data = NULL;
1833 }
1834
1835 FreeXid(xid);
1836 return rc;
1837 }
1838
1839 static int cifs_readpage_worker(struct file *file, struct page *page,
1840 loff_t *poffset)
1841 {
1842 char *read_data;
1843 int rc;
1844
1845 page_cache_get(page);
1846 read_data = kmap(page);
1847 /* for reads over a certain size could initiate async read ahead */
1848
1849 rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
1850
1851 if (rc < 0)
1852 goto io_error;
1853 else
1854 cFYI(1, ("Bytes read %d",rc));
1855
1856 file->f_path.dentry->d_inode->i_atime =
1857 current_fs_time(file->f_path.dentry->d_inode->i_sb);
1858
1859 if (PAGE_CACHE_SIZE > rc)
1860 memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
1861
1862 flush_dcache_page(page);
1863 SetPageUptodate(page);
1864 rc = 0;
1865
1866 io_error:
1867 kunmap(page);
1868 page_cache_release(page);
1869 return rc;
1870 }
1871
1872 static int cifs_readpage(struct file *file, struct page *page)
1873 {
1874 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1875 int rc = -EACCES;
1876 int xid;
1877
1878 xid = GetXid();
1879
1880 if (file->private_data == NULL) {
1881 FreeXid(xid);
1882 return -EBADF;
1883 }
1884
1885 cFYI(1, ("readpage %p at offset %d 0x%x\n",
1886 page, (int)offset, (int)offset));
1887
1888 rc = cifs_readpage_worker(file, page, &offset);
1889
1890 unlock_page(page);
1891
1892 FreeXid(xid);
1893 return rc;
1894 }
1895
1896 /* We do not want to update the file size from server for inodes
1897 open for write - to avoid races with writepage extending
1898 the file - in the future we could consider allowing
1899 refreshing the inode only on increases in the file size
1900 but this is tricky to do without racing with writebehind
1901 page caching in the current Linux kernel design */
1902 int is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
1903 {
1904 struct cifsFileInfo *open_file = NULL;
1905
1906 if (cifsInode)
1907 open_file = find_writable_file(cifsInode);
1908
1909 if(open_file) {
1910 struct cifs_sb_info *cifs_sb;
1911
1912 /* there is not actually a write pending so let
1913 this handle go free and allow it to
1914 be closable if needed */
1915 atomic_dec(&open_file->wrtPending);
1916
1917 cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
1918 if ( cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO ) {
1919 /* since no page cache to corrupt on directio
1920 we can change size safely */
1921 return 1;
1922 }
1923
1924 if(i_size_read(&cifsInode->vfs_inode) < end_of_file)
1925 return 1;
1926
1927 return 0;
1928 } else
1929 return 1;
1930 }
1931
1932 static int cifs_prepare_write(struct file *file, struct page *page,
1933 unsigned from, unsigned to)
1934 {
1935 int rc = 0;
1936 loff_t i_size;
1937 loff_t offset;
1938
1939 cFYI(1, ("prepare write for page %p from %d to %d",page,from,to));
1940 if (PageUptodate(page))
1941 return 0;
1942
1943 /* If we are writing a full page it will be up to date,
1944 no need to read from the server */
1945 if ((to == PAGE_CACHE_SIZE) && (from == 0)) {
1946 SetPageUptodate(page);
1947 return 0;
1948 }
1949
1950 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1951 i_size = i_size_read(page->mapping->host);
1952
1953 if ((offset >= i_size) ||
1954 ((from == 0) && (offset + to) >= i_size)) {
1955 /*
1956 * We don't need to read data beyond the end of the file.
1957 * zero it, and set the page uptodate
1958 */
1959 void *kaddr = kmap_atomic(page, KM_USER0);
1960
1961 if (from)
1962 memset(kaddr, 0, from);
1963 if (to < PAGE_CACHE_SIZE)
1964 memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
1965 flush_dcache_page(page);
1966 kunmap_atomic(kaddr, KM_USER0);
1967 SetPageUptodate(page);
1968 } else if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
1969 /* might as well read a page, it is fast enough */
1970 rc = cifs_readpage_worker(file, page, &offset);
1971 } else {
1972 /* we could try using another file handle if there is one -
1973 but how would we lock it to prevent close of that handle
1974 racing with this read? In any case
1975 this will be written out by commit_write so is fine */
1976 }
1977
1978 /* we do not need to pass errors back
1979 e.g. if we do not have read access to the file
1980 because cifs_commit_write will do the right thing. -- shaggy */
1981
1982 return 0;
1983 }
1984
1985 const struct address_space_operations cifs_addr_ops = {
1986 .readpage = cifs_readpage,
1987 .readpages = cifs_readpages,
1988 .writepage = cifs_writepage,
1989 .writepages = cifs_writepages,
1990 .prepare_write = cifs_prepare_write,
1991 .commit_write = cifs_commit_write,
1992 .set_page_dirty = __set_page_dirty_nobuffers,
1993 /* .sync_page = cifs_sync_page, */
1994 /* .direct_IO = */
1995 };
1996
1997 /*
1998 * cifs_readpages requires the server to support a buffer large enough to
1999 * contain the header plus one complete page of data. Otherwise, we need
2000 * to leave cifs_readpages out of the address space operations.
2001 */
2002 const struct address_space_operations cifs_addr_ops_smallbuf = {
2003 .readpage = cifs_readpage,
2004 .writepage = cifs_writepage,
2005 .writepages = cifs_writepages,
2006 .prepare_write = cifs_prepare_write,
2007 .commit_write = cifs_commit_write,
2008 .set_page_dirty = __set_page_dirty_nobuffers,
2009 /* .sync_page = cifs_sync_page, */
2010 /* .direct_IO = */
2011 };
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