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[GitHub/mt8127/android_kernel_alcatel_ttab.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., 2002,2010
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/writeback.h>
31 #include <linux/task_io_accounting_ops.h>
32 #include <linux/delay.h>
33 #include <linux/mount.h>
34 #include <linux/slab.h>
35 #include <linux/swap.h>
36 #include <asm/div64.h>
37 #include "cifsfs.h"
38 #include "cifspdu.h"
39 #include "cifsglob.h"
40 #include "cifsproto.h"
41 #include "cifs_unicode.h"
42 #include "cifs_debug.h"
43 #include "cifs_fs_sb.h"
44 #include "fscache.h"
45
46 static inline int cifs_convert_flags(unsigned int flags)
47 {
48 if ((flags & O_ACCMODE) == O_RDONLY)
49 return GENERIC_READ;
50 else if ((flags & O_ACCMODE) == O_WRONLY)
51 return GENERIC_WRITE;
52 else if ((flags & O_ACCMODE) == O_RDWR) {
53 /* GENERIC_ALL is too much permission to request
54 can cause unnecessary access denied on create */
55 /* return GENERIC_ALL; */
56 return (GENERIC_READ | GENERIC_WRITE);
57 }
58
59 return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
60 FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
61 FILE_READ_DATA);
62 }
63
64 static u32 cifs_posix_convert_flags(unsigned int flags)
65 {
66 u32 posix_flags = 0;
67
68 if ((flags & O_ACCMODE) == O_RDONLY)
69 posix_flags = SMB_O_RDONLY;
70 else if ((flags & O_ACCMODE) == O_WRONLY)
71 posix_flags = SMB_O_WRONLY;
72 else if ((flags & O_ACCMODE) == O_RDWR)
73 posix_flags = SMB_O_RDWR;
74
75 if (flags & O_CREAT)
76 posix_flags |= SMB_O_CREAT;
77 if (flags & O_EXCL)
78 posix_flags |= SMB_O_EXCL;
79 if (flags & O_TRUNC)
80 posix_flags |= SMB_O_TRUNC;
81 /* be safe and imply O_SYNC for O_DSYNC */
82 if (flags & O_DSYNC)
83 posix_flags |= SMB_O_SYNC;
84 if (flags & O_DIRECTORY)
85 posix_flags |= SMB_O_DIRECTORY;
86 if (flags & O_NOFOLLOW)
87 posix_flags |= SMB_O_NOFOLLOW;
88 if (flags & O_DIRECT)
89 posix_flags |= SMB_O_DIRECT;
90
91 return posix_flags;
92 }
93
94 static inline int cifs_get_disposition(unsigned int flags)
95 {
96 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
97 return FILE_CREATE;
98 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
99 return FILE_OVERWRITE_IF;
100 else if ((flags & O_CREAT) == O_CREAT)
101 return FILE_OPEN_IF;
102 else if ((flags & O_TRUNC) == O_TRUNC)
103 return FILE_OVERWRITE;
104 else
105 return FILE_OPEN;
106 }
107
108 int cifs_posix_open(char *full_path, struct inode **pinode,
109 struct super_block *sb, int mode, unsigned int f_flags,
110 __u32 *poplock, __u16 *pnetfid, unsigned int xid)
111 {
112 int rc;
113 FILE_UNIX_BASIC_INFO *presp_data;
114 __u32 posix_flags = 0;
115 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
116 struct cifs_fattr fattr;
117 struct tcon_link *tlink;
118 struct cifs_tcon *tcon;
119
120 cFYI(1, "posix open %s", full_path);
121
122 presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
123 if (presp_data == NULL)
124 return -ENOMEM;
125
126 tlink = cifs_sb_tlink(cifs_sb);
127 if (IS_ERR(tlink)) {
128 rc = PTR_ERR(tlink);
129 goto posix_open_ret;
130 }
131
132 tcon = tlink_tcon(tlink);
133 mode &= ~current_umask();
134
135 posix_flags = cifs_posix_convert_flags(f_flags);
136 rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
137 poplock, full_path, cifs_sb->local_nls,
138 cifs_sb->mnt_cifs_flags &
139 CIFS_MOUNT_MAP_SPECIAL_CHR);
140 cifs_put_tlink(tlink);
141
142 if (rc)
143 goto posix_open_ret;
144
145 if (presp_data->Type == cpu_to_le32(-1))
146 goto posix_open_ret; /* open ok, caller does qpathinfo */
147
148 if (!pinode)
149 goto posix_open_ret; /* caller does not need info */
150
151 cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
152
153 /* get new inode and set it up */
154 if (*pinode == NULL) {
155 cifs_fill_uniqueid(sb, &fattr);
156 *pinode = cifs_iget(sb, &fattr);
157 if (!*pinode) {
158 rc = -ENOMEM;
159 goto posix_open_ret;
160 }
161 } else {
162 cifs_fattr_to_inode(*pinode, &fattr);
163 }
164
165 posix_open_ret:
166 kfree(presp_data);
167 return rc;
168 }
169
170 static int
171 cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
172 struct cifs_tcon *tcon, unsigned int f_flags, __u32 *oplock,
173 struct cifs_fid *fid, unsigned int xid)
174 {
175 int rc;
176 int desired_access;
177 int disposition;
178 int create_options = CREATE_NOT_DIR;
179 FILE_ALL_INFO *buf;
180
181 if (!tcon->ses->server->ops->open)
182 return -ENOSYS;
183
184 desired_access = cifs_convert_flags(f_flags);
185
186 /*********************************************************************
187 * open flag mapping table:
188 *
189 * POSIX Flag CIFS Disposition
190 * ---------- ----------------
191 * O_CREAT FILE_OPEN_IF
192 * O_CREAT | O_EXCL FILE_CREATE
193 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
194 * O_TRUNC FILE_OVERWRITE
195 * none of the above FILE_OPEN
196 *
197 * Note that there is not a direct match between disposition
198 * FILE_SUPERSEDE (ie create whether or not file exists although
199 * O_CREAT | O_TRUNC is similar but truncates the existing
200 * file rather than creating a new file as FILE_SUPERSEDE does
201 * (which uses the attributes / metadata passed in on open call)
202 *?
203 *? O_SYNC is a reasonable match to CIFS writethrough flag
204 *? and the read write flags match reasonably. O_LARGEFILE
205 *? is irrelevant because largefile support is always used
206 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
207 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
208 *********************************************************************/
209
210 disposition = cifs_get_disposition(f_flags);
211
212 /* BB pass O_SYNC flag through on file attributes .. BB */
213
214 buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
215 if (!buf)
216 return -ENOMEM;
217
218 if (backup_cred(cifs_sb))
219 create_options |= CREATE_OPEN_BACKUP_INTENT;
220
221 rc = tcon->ses->server->ops->open(xid, tcon, full_path, disposition,
222 desired_access, create_options, fid,
223 oplock, buf, cifs_sb);
224
225 if (rc)
226 goto out;
227
228 if (tcon->unix_ext)
229 rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
230 xid);
231 else
232 rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
233 xid, &fid->netfid);
234
235 out:
236 kfree(buf);
237 return rc;
238 }
239
240 struct cifsFileInfo *
241 cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
242 struct tcon_link *tlink, __u32 oplock)
243 {
244 struct dentry *dentry = file->f_path.dentry;
245 struct inode *inode = dentry->d_inode;
246 struct cifsInodeInfo *cinode = CIFS_I(inode);
247 struct cifsFileInfo *cfile;
248
249 cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
250 if (cfile == NULL)
251 return cfile;
252
253 cfile->count = 1;
254 cfile->pid = current->tgid;
255 cfile->uid = current_fsuid();
256 cfile->dentry = dget(dentry);
257 cfile->f_flags = file->f_flags;
258 cfile->invalidHandle = false;
259 cfile->tlink = cifs_get_tlink(tlink);
260 mutex_init(&cfile->fh_mutex);
261 INIT_WORK(&cfile->oplock_break, cifs_oplock_break);
262 INIT_LIST_HEAD(&cfile->llist);
263 tlink_tcon(tlink)->ses->server->ops->set_fid(cfile, fid, oplock);
264
265 spin_lock(&cifs_file_list_lock);
266 list_add(&cfile->tlist, &(tlink_tcon(tlink)->openFileList));
267 /* if readable file instance put first in list*/
268 if (file->f_mode & FMODE_READ)
269 list_add(&cfile->flist, &cinode->openFileList);
270 else
271 list_add_tail(&cfile->flist, &cinode->openFileList);
272 spin_unlock(&cifs_file_list_lock);
273
274 file->private_data = cfile;
275 return cfile;
276 }
277
278 static void cifs_del_lock_waiters(struct cifsLockInfo *lock);
279
280 struct cifsFileInfo *
281 cifsFileInfo_get(struct cifsFileInfo *cifs_file)
282 {
283 spin_lock(&cifs_file_list_lock);
284 cifsFileInfo_get_locked(cifs_file);
285 spin_unlock(&cifs_file_list_lock);
286 return cifs_file;
287 }
288
289 /*
290 * Release a reference on the file private data. This may involve closing
291 * the filehandle out on the server. Must be called without holding
292 * cifs_file_list_lock.
293 */
294 void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
295 {
296 struct inode *inode = cifs_file->dentry->d_inode;
297 struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink);
298 struct cifsInodeInfo *cifsi = CIFS_I(inode);
299 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
300 struct cifsLockInfo *li, *tmp;
301
302 spin_lock(&cifs_file_list_lock);
303 if (--cifs_file->count > 0) {
304 spin_unlock(&cifs_file_list_lock);
305 return;
306 }
307
308 /* remove it from the lists */
309 list_del(&cifs_file->flist);
310 list_del(&cifs_file->tlist);
311
312 if (list_empty(&cifsi->openFileList)) {
313 cFYI(1, "closing last open instance for inode %p",
314 cifs_file->dentry->d_inode);
315 /*
316 * In strict cache mode we need invalidate mapping on the last
317 * close because it may cause a error when we open this file
318 * again and get at least level II oplock.
319 */
320 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
321 CIFS_I(inode)->invalid_mapping = true;
322 cifs_set_oplock_level(cifsi, 0);
323 }
324 spin_unlock(&cifs_file_list_lock);
325
326 cancel_work_sync(&cifs_file->oplock_break);
327
328 if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
329 struct TCP_Server_Info *server = tcon->ses->server;
330 unsigned int xid;
331 int rc = -ENOSYS;
332
333 xid = get_xid();
334 if (server->ops->close)
335 rc = server->ops->close(xid, tcon, &cifs_file->fid);
336 free_xid(xid);
337 }
338
339 /* Delete any outstanding lock records. We'll lose them when the file
340 * is closed anyway.
341 */
342 mutex_lock(&cifsi->lock_mutex);
343 list_for_each_entry_safe(li, tmp, &cifs_file->llist, llist) {
344 list_del(&li->llist);
345 cifs_del_lock_waiters(li);
346 kfree(li);
347 }
348 mutex_unlock(&cifsi->lock_mutex);
349
350 cifs_put_tlink(cifs_file->tlink);
351 dput(cifs_file->dentry);
352 kfree(cifs_file);
353 }
354
355 int cifs_open(struct inode *inode, struct file *file)
356 {
357 int rc = -EACCES;
358 unsigned int xid;
359 __u32 oplock;
360 struct cifs_sb_info *cifs_sb;
361 struct cifs_tcon *tcon;
362 struct tcon_link *tlink;
363 struct cifsFileInfo *cfile = NULL;
364 char *full_path = NULL;
365 bool posix_open_ok = false;
366 struct cifs_fid fid;
367
368 xid = get_xid();
369
370 cifs_sb = CIFS_SB(inode->i_sb);
371 tlink = cifs_sb_tlink(cifs_sb);
372 if (IS_ERR(tlink)) {
373 free_xid(xid);
374 return PTR_ERR(tlink);
375 }
376 tcon = tlink_tcon(tlink);
377
378 full_path = build_path_from_dentry(file->f_path.dentry);
379 if (full_path == NULL) {
380 rc = -ENOMEM;
381 goto out;
382 }
383
384 cFYI(1, "inode = 0x%p file flags are 0x%x for %s",
385 inode, file->f_flags, full_path);
386
387 if (tcon->ses->server->oplocks)
388 oplock = REQ_OPLOCK;
389 else
390 oplock = 0;
391
392 if (!tcon->broken_posix_open && tcon->unix_ext &&
393 cap_unix(tcon->ses) && (CIFS_UNIX_POSIX_PATH_OPS_CAP &
394 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
395 /* can not refresh inode info since size could be stale */
396 rc = cifs_posix_open(full_path, &inode, inode->i_sb,
397 cifs_sb->mnt_file_mode /* ignored */,
398 file->f_flags, &oplock, &fid.netfid, xid);
399 if (rc == 0) {
400 cFYI(1, "posix open succeeded");
401 posix_open_ok = true;
402 } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
403 if (tcon->ses->serverNOS)
404 cERROR(1, "server %s of type %s returned"
405 " unexpected error on SMB posix open"
406 ", disabling posix open support."
407 " Check if server update available.",
408 tcon->ses->serverName,
409 tcon->ses->serverNOS);
410 tcon->broken_posix_open = true;
411 } else if ((rc != -EIO) && (rc != -EREMOTE) &&
412 (rc != -EOPNOTSUPP)) /* path not found or net err */
413 goto out;
414 /*
415 * Else fallthrough to retry open the old way on network i/o
416 * or DFS errors.
417 */
418 }
419
420 if (!posix_open_ok) {
421 rc = cifs_nt_open(full_path, inode, cifs_sb, tcon,
422 file->f_flags, &oplock, &fid, xid);
423 if (rc)
424 goto out;
425 }
426
427 cfile = cifs_new_fileinfo(&fid, file, tlink, oplock);
428 if (cfile == NULL) {
429 if (tcon->ses->server->ops->close)
430 tcon->ses->server->ops->close(xid, tcon, &fid);
431 rc = -ENOMEM;
432 goto out;
433 }
434
435 cifs_fscache_set_inode_cookie(inode, file);
436
437 if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
438 /*
439 * Time to set mode which we can not set earlier due to
440 * problems creating new read-only files.
441 */
442 struct cifs_unix_set_info_args args = {
443 .mode = inode->i_mode,
444 .uid = NO_CHANGE_64,
445 .gid = NO_CHANGE_64,
446 .ctime = NO_CHANGE_64,
447 .atime = NO_CHANGE_64,
448 .mtime = NO_CHANGE_64,
449 .device = 0,
450 };
451 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid.netfid,
452 cfile->pid);
453 }
454
455 out:
456 kfree(full_path);
457 free_xid(xid);
458 cifs_put_tlink(tlink);
459 return rc;
460 }
461
462 /*
463 * Try to reacquire byte range locks that were released when session
464 * to server was lost
465 */
466 static int cifs_relock_file(struct cifsFileInfo *cifsFile)
467 {
468 int rc = 0;
469
470 /* BB list all locks open on this file and relock */
471
472 return rc;
473 }
474
475 static int
476 cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
477 {
478 int rc = -EACCES;
479 unsigned int xid;
480 __u32 oplock;
481 struct cifs_sb_info *cifs_sb;
482 struct cifs_tcon *tcon;
483 struct TCP_Server_Info *server;
484 struct cifsInodeInfo *cinode;
485 struct inode *inode;
486 char *full_path = NULL;
487 int desired_access;
488 int disposition = FILE_OPEN;
489 int create_options = CREATE_NOT_DIR;
490 struct cifs_fid fid;
491
492 xid = get_xid();
493 mutex_lock(&cfile->fh_mutex);
494 if (!cfile->invalidHandle) {
495 mutex_unlock(&cfile->fh_mutex);
496 rc = 0;
497 free_xid(xid);
498 return rc;
499 }
500
501 inode = cfile->dentry->d_inode;
502 cifs_sb = CIFS_SB(inode->i_sb);
503 tcon = tlink_tcon(cfile->tlink);
504 server = tcon->ses->server;
505
506 /*
507 * Can not grab rename sem here because various ops, including those
508 * that already have the rename sem can end up causing writepage to get
509 * called and if the server was down that means we end up here, and we
510 * can never tell if the caller already has the rename_sem.
511 */
512 full_path = build_path_from_dentry(cfile->dentry);
513 if (full_path == NULL) {
514 rc = -ENOMEM;
515 mutex_unlock(&cfile->fh_mutex);
516 free_xid(xid);
517 return rc;
518 }
519
520 cFYI(1, "inode = 0x%p file flags 0x%x for %s", inode, cfile->f_flags,
521 full_path);
522
523 if (tcon->ses->server->oplocks)
524 oplock = REQ_OPLOCK;
525 else
526 oplock = 0;
527
528 if (tcon->unix_ext && cap_unix(tcon->ses) &&
529 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
530 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
531 /*
532 * O_CREAT, O_EXCL and O_TRUNC already had their effect on the
533 * original open. Must mask them off for a reopen.
534 */
535 unsigned int oflags = cfile->f_flags &
536 ~(O_CREAT | O_EXCL | O_TRUNC);
537
538 rc = cifs_posix_open(full_path, NULL, inode->i_sb,
539 cifs_sb->mnt_file_mode /* ignored */,
540 oflags, &oplock, &fid.netfid, xid);
541 if (rc == 0) {
542 cFYI(1, "posix reopen succeeded");
543 goto reopen_success;
544 }
545 /*
546 * fallthrough to retry open the old way on errors, especially
547 * in the reconnect path it is important to retry hard
548 */
549 }
550
551 desired_access = cifs_convert_flags(cfile->f_flags);
552
553 if (backup_cred(cifs_sb))
554 create_options |= CREATE_OPEN_BACKUP_INTENT;
555
556 /*
557 * Can not refresh inode by passing in file_info buf to be returned by
558 * CIFSSMBOpen and then calling get_inode_info with returned buf since
559 * file might have write behind data that needs to be flushed and server
560 * version of file size can be stale. If we knew for sure that inode was
561 * not dirty locally we could do this.
562 */
563 rc = server->ops->open(xid, tcon, full_path, disposition,
564 desired_access, create_options, &fid, &oplock,
565 NULL, cifs_sb);
566 if (rc) {
567 mutex_unlock(&cfile->fh_mutex);
568 cFYI(1, "cifs_reopen returned 0x%x", rc);
569 cFYI(1, "oplock: %d", oplock);
570 goto reopen_error_exit;
571 }
572
573 reopen_success:
574 cfile->invalidHandle = false;
575 mutex_unlock(&cfile->fh_mutex);
576 cinode = CIFS_I(inode);
577
578 if (can_flush) {
579 rc = filemap_write_and_wait(inode->i_mapping);
580 mapping_set_error(inode->i_mapping, rc);
581
582 if (tcon->unix_ext)
583 rc = cifs_get_inode_info_unix(&inode, full_path,
584 inode->i_sb, xid);
585 else
586 rc = cifs_get_inode_info(&inode, full_path, NULL,
587 inode->i_sb, xid, NULL);
588 }
589 /*
590 * Else we are writing out data to server already and could deadlock if
591 * we tried to flush data, and since we do not know if we have data that
592 * would invalidate the current end of file on the server we can not go
593 * to the server to get the new inode info.
594 */
595
596 server->ops->set_fid(cfile, &fid, oplock);
597 cifs_relock_file(cfile);
598
599 reopen_error_exit:
600 kfree(full_path);
601 free_xid(xid);
602 return rc;
603 }
604
605 int cifs_close(struct inode *inode, struct file *file)
606 {
607 if (file->private_data != NULL) {
608 cifsFileInfo_put(file->private_data);
609 file->private_data = NULL;
610 }
611
612 /* return code from the ->release op is always ignored */
613 return 0;
614 }
615
616 int cifs_closedir(struct inode *inode, struct file *file)
617 {
618 int rc = 0;
619 unsigned int xid;
620 struct cifsFileInfo *cfile = file->private_data;
621 char *tmp;
622
623 cFYI(1, "Closedir inode = 0x%p", inode);
624
625 xid = get_xid();
626
627 if (cfile) {
628 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
629
630 cFYI(1, "Freeing private data in close dir");
631 spin_lock(&cifs_file_list_lock);
632 if (!cfile->srch_inf.endOfSearch && !cfile->invalidHandle) {
633 cfile->invalidHandle = true;
634 spin_unlock(&cifs_file_list_lock);
635 rc = CIFSFindClose(xid, tcon, cfile->fid.netfid);
636 cFYI(1, "Closing uncompleted readdir with rc %d", rc);
637 /* not much we can do if it fails anyway, ignore rc */
638 rc = 0;
639 } else
640 spin_unlock(&cifs_file_list_lock);
641 tmp = cfile->srch_inf.ntwrk_buf_start;
642 if (tmp) {
643 cFYI(1, "closedir free smb buf in srch struct");
644 cfile->srch_inf.ntwrk_buf_start = NULL;
645 if (cfile->srch_inf.smallBuf)
646 cifs_small_buf_release(tmp);
647 else
648 cifs_buf_release(tmp);
649 }
650 cifs_put_tlink(cfile->tlink);
651 kfree(file->private_data);
652 file->private_data = NULL;
653 }
654 /* BB can we lock the filestruct while this is going on? */
655 free_xid(xid);
656 return rc;
657 }
658
659 static struct cifsLockInfo *
660 cifs_lock_init(__u64 offset, __u64 length, __u8 type)
661 {
662 struct cifsLockInfo *lock =
663 kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
664 if (!lock)
665 return lock;
666 lock->offset = offset;
667 lock->length = length;
668 lock->type = type;
669 lock->pid = current->tgid;
670 INIT_LIST_HEAD(&lock->blist);
671 init_waitqueue_head(&lock->block_q);
672 return lock;
673 }
674
675 static void
676 cifs_del_lock_waiters(struct cifsLockInfo *lock)
677 {
678 struct cifsLockInfo *li, *tmp;
679 list_for_each_entry_safe(li, tmp, &lock->blist, blist) {
680 list_del_init(&li->blist);
681 wake_up(&li->block_q);
682 }
683 }
684
685 static bool
686 cifs_find_fid_lock_conflict(struct cifsFileInfo *cfile, __u64 offset,
687 __u64 length, __u8 type, struct cifsFileInfo *cur,
688 struct cifsLockInfo **conf_lock)
689 {
690 struct cifsLockInfo *li;
691 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
692
693 list_for_each_entry(li, &cfile->llist, llist) {
694 if (offset + length <= li->offset ||
695 offset >= li->offset + li->length)
696 continue;
697 else if ((type & server->vals->shared_lock_type) &&
698 ((server->ops->compare_fids(cur, cfile) &&
699 current->tgid == li->pid) || type == li->type))
700 continue;
701 else {
702 *conf_lock = li;
703 return true;
704 }
705 }
706 return false;
707 }
708
709 static bool
710 cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
711 __u8 type, struct cifsLockInfo **conf_lock)
712 {
713 bool rc = false;
714 struct cifsFileInfo *fid, *tmp;
715 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
716
717 spin_lock(&cifs_file_list_lock);
718 list_for_each_entry_safe(fid, tmp, &cinode->openFileList, flist) {
719 rc = cifs_find_fid_lock_conflict(fid, offset, length, type,
720 cfile, conf_lock);
721 if (rc)
722 break;
723 }
724 spin_unlock(&cifs_file_list_lock);
725
726 return rc;
727 }
728
729 /*
730 * Check if there is another lock that prevents us to set the lock (mandatory
731 * style). If such a lock exists, update the flock structure with its
732 * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
733 * or leave it the same if we can't. Returns 0 if we don't need to request to
734 * the server or 1 otherwise.
735 */
736 static int
737 cifs_lock_test(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
738 __u8 type, struct file_lock *flock)
739 {
740 int rc = 0;
741 struct cifsLockInfo *conf_lock;
742 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
743 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
744 bool exist;
745
746 mutex_lock(&cinode->lock_mutex);
747
748 exist = cifs_find_lock_conflict(cfile, offset, length, type,
749 &conf_lock);
750 if (exist) {
751 flock->fl_start = conf_lock->offset;
752 flock->fl_end = conf_lock->offset + conf_lock->length - 1;
753 flock->fl_pid = conf_lock->pid;
754 if (conf_lock->type & server->vals->shared_lock_type)
755 flock->fl_type = F_RDLCK;
756 else
757 flock->fl_type = F_WRLCK;
758 } else if (!cinode->can_cache_brlcks)
759 rc = 1;
760 else
761 flock->fl_type = F_UNLCK;
762
763 mutex_unlock(&cinode->lock_mutex);
764 return rc;
765 }
766
767 static void
768 cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock)
769 {
770 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
771 mutex_lock(&cinode->lock_mutex);
772 list_add_tail(&lock->llist, &cfile->llist);
773 mutex_unlock(&cinode->lock_mutex);
774 }
775
776 /*
777 * Set the byte-range lock (mandatory style). Returns:
778 * 1) 0, if we set the lock and don't need to request to the server;
779 * 2) 1, if no locks prevent us but we need to request to the server;
780 * 3) -EACCESS, if there is a lock that prevents us and wait is false.
781 */
782 static int
783 cifs_lock_add_if(struct cifsFileInfo *cfile, struct cifsLockInfo *lock,
784 bool wait)
785 {
786 struct cifsLockInfo *conf_lock;
787 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
788 bool exist;
789 int rc = 0;
790
791 try_again:
792 exist = false;
793 mutex_lock(&cinode->lock_mutex);
794
795 exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length,
796 lock->type, &conf_lock);
797 if (!exist && cinode->can_cache_brlcks) {
798 list_add_tail(&lock->llist, &cfile->llist);
799 mutex_unlock(&cinode->lock_mutex);
800 return rc;
801 }
802
803 if (!exist)
804 rc = 1;
805 else if (!wait)
806 rc = -EACCES;
807 else {
808 list_add_tail(&lock->blist, &conf_lock->blist);
809 mutex_unlock(&cinode->lock_mutex);
810 rc = wait_event_interruptible(lock->block_q,
811 (lock->blist.prev == &lock->blist) &&
812 (lock->blist.next == &lock->blist));
813 if (!rc)
814 goto try_again;
815 mutex_lock(&cinode->lock_mutex);
816 list_del_init(&lock->blist);
817 }
818
819 mutex_unlock(&cinode->lock_mutex);
820 return rc;
821 }
822
823 /*
824 * Check if there is another lock that prevents us to set the lock (posix
825 * style). If such a lock exists, update the flock structure with its
826 * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
827 * or leave it the same if we can't. Returns 0 if we don't need to request to
828 * the server or 1 otherwise.
829 */
830 static int
831 cifs_posix_lock_test(struct file *file, struct file_lock *flock)
832 {
833 int rc = 0;
834 struct cifsInodeInfo *cinode = CIFS_I(file->f_path.dentry->d_inode);
835 unsigned char saved_type = flock->fl_type;
836
837 if ((flock->fl_flags & FL_POSIX) == 0)
838 return 1;
839
840 mutex_lock(&cinode->lock_mutex);
841 posix_test_lock(file, flock);
842
843 if (flock->fl_type == F_UNLCK && !cinode->can_cache_brlcks) {
844 flock->fl_type = saved_type;
845 rc = 1;
846 }
847
848 mutex_unlock(&cinode->lock_mutex);
849 return rc;
850 }
851
852 /*
853 * Set the byte-range lock (posix style). Returns:
854 * 1) 0, if we set the lock and don't need to request to the server;
855 * 2) 1, if we need to request to the server;
856 * 3) <0, if the error occurs while setting the lock.
857 */
858 static int
859 cifs_posix_lock_set(struct file *file, struct file_lock *flock)
860 {
861 struct cifsInodeInfo *cinode = CIFS_I(file->f_path.dentry->d_inode);
862 int rc = 1;
863
864 if ((flock->fl_flags & FL_POSIX) == 0)
865 return rc;
866
867 try_again:
868 mutex_lock(&cinode->lock_mutex);
869 if (!cinode->can_cache_brlcks) {
870 mutex_unlock(&cinode->lock_mutex);
871 return rc;
872 }
873
874 rc = posix_lock_file(file, flock, NULL);
875 mutex_unlock(&cinode->lock_mutex);
876 if (rc == FILE_LOCK_DEFERRED) {
877 rc = wait_event_interruptible(flock->fl_wait, !flock->fl_next);
878 if (!rc)
879 goto try_again;
880 locks_delete_block(flock);
881 }
882 return rc;
883 }
884
885 static int
886 cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
887 {
888 unsigned int xid;
889 int rc = 0, stored_rc;
890 struct cifsLockInfo *li, *tmp;
891 struct cifs_tcon *tcon;
892 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
893 unsigned int num, max_num, max_buf;
894 LOCKING_ANDX_RANGE *buf, *cur;
895 int types[] = {LOCKING_ANDX_LARGE_FILES,
896 LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES};
897 int i;
898
899 xid = get_xid();
900 tcon = tlink_tcon(cfile->tlink);
901
902 mutex_lock(&cinode->lock_mutex);
903 if (!cinode->can_cache_brlcks) {
904 mutex_unlock(&cinode->lock_mutex);
905 free_xid(xid);
906 return rc;
907 }
908
909 /*
910 * Accessing maxBuf is racy with cifs_reconnect - need to store value
911 * and check it for zero before using.
912 */
913 max_buf = tcon->ses->server->maxBuf;
914 if (!max_buf) {
915 mutex_unlock(&cinode->lock_mutex);
916 free_xid(xid);
917 return -EINVAL;
918 }
919
920 max_num = (max_buf - sizeof(struct smb_hdr)) /
921 sizeof(LOCKING_ANDX_RANGE);
922 buf = kzalloc(max_num * sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
923 if (!buf) {
924 mutex_unlock(&cinode->lock_mutex);
925 free_xid(xid);
926 return -ENOMEM;
927 }
928
929 for (i = 0; i < 2; i++) {
930 cur = buf;
931 num = 0;
932 list_for_each_entry_safe(li, tmp, &cfile->llist, llist) {
933 if (li->type != types[i])
934 continue;
935 cur->Pid = cpu_to_le16(li->pid);
936 cur->LengthLow = cpu_to_le32((u32)li->length);
937 cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
938 cur->OffsetLow = cpu_to_le32((u32)li->offset);
939 cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
940 if (++num == max_num) {
941 stored_rc = cifs_lockv(xid, tcon,
942 cfile->fid.netfid,
943 (__u8)li->type, 0, num,
944 buf);
945 if (stored_rc)
946 rc = stored_rc;
947 cur = buf;
948 num = 0;
949 } else
950 cur++;
951 }
952
953 if (num) {
954 stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
955 (__u8)types[i], 0, num, buf);
956 if (stored_rc)
957 rc = stored_rc;
958 }
959 }
960
961 cinode->can_cache_brlcks = false;
962 mutex_unlock(&cinode->lock_mutex);
963
964 kfree(buf);
965 free_xid(xid);
966 return rc;
967 }
968
969 /* copied from fs/locks.c with a name change */
970 #define cifs_for_each_lock(inode, lockp) \
971 for (lockp = &inode->i_flock; *lockp != NULL; \
972 lockp = &(*lockp)->fl_next)
973
974 struct lock_to_push {
975 struct list_head llist;
976 __u64 offset;
977 __u64 length;
978 __u32 pid;
979 __u16 netfid;
980 __u8 type;
981 };
982
983 static int
984 cifs_push_posix_locks(struct cifsFileInfo *cfile)
985 {
986 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
987 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
988 struct file_lock *flock, **before;
989 unsigned int count = 0, i = 0;
990 int rc = 0, xid, type;
991 struct list_head locks_to_send, *el;
992 struct lock_to_push *lck, *tmp;
993 __u64 length;
994
995 xid = get_xid();
996
997 mutex_lock(&cinode->lock_mutex);
998 if (!cinode->can_cache_brlcks) {
999 mutex_unlock(&cinode->lock_mutex);
1000 free_xid(xid);
1001 return rc;
1002 }
1003
1004 lock_flocks();
1005 cifs_for_each_lock(cfile->dentry->d_inode, before) {
1006 if ((*before)->fl_flags & FL_POSIX)
1007 count++;
1008 }
1009 unlock_flocks();
1010
1011 INIT_LIST_HEAD(&locks_to_send);
1012
1013 /*
1014 * Allocating count locks is enough because no FL_POSIX locks can be
1015 * added to the list while we are holding cinode->lock_mutex that
1016 * protects locking operations of this inode.
1017 */
1018 for (; i < count; i++) {
1019 lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
1020 if (!lck) {
1021 rc = -ENOMEM;
1022 goto err_out;
1023 }
1024 list_add_tail(&lck->llist, &locks_to_send);
1025 }
1026
1027 el = locks_to_send.next;
1028 lock_flocks();
1029 cifs_for_each_lock(cfile->dentry->d_inode, before) {
1030 flock = *before;
1031 if ((flock->fl_flags & FL_POSIX) == 0)
1032 continue;
1033 if (el == &locks_to_send) {
1034 /*
1035 * The list ended. We don't have enough allocated
1036 * structures - something is really wrong.
1037 */
1038 cERROR(1, "Can't push all brlocks!");
1039 break;
1040 }
1041 length = 1 + flock->fl_end - flock->fl_start;
1042 if (flock->fl_type == F_RDLCK || flock->fl_type == F_SHLCK)
1043 type = CIFS_RDLCK;
1044 else
1045 type = CIFS_WRLCK;
1046 lck = list_entry(el, struct lock_to_push, llist);
1047 lck->pid = flock->fl_pid;
1048 lck->netfid = cfile->fid.netfid;
1049 lck->length = length;
1050 lck->type = type;
1051 lck->offset = flock->fl_start;
1052 el = el->next;
1053 }
1054 unlock_flocks();
1055
1056 list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
1057 int stored_rc;
1058
1059 stored_rc = CIFSSMBPosixLock(xid, tcon, lck->netfid, lck->pid,
1060 lck->offset, lck->length, NULL,
1061 lck->type, 0);
1062 if (stored_rc)
1063 rc = stored_rc;
1064 list_del(&lck->llist);
1065 kfree(lck);
1066 }
1067
1068 out:
1069 cinode->can_cache_brlcks = false;
1070 mutex_unlock(&cinode->lock_mutex);
1071
1072 free_xid(xid);
1073 return rc;
1074 err_out:
1075 list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
1076 list_del(&lck->llist);
1077 kfree(lck);
1078 }
1079 goto out;
1080 }
1081
1082 static int
1083 cifs_push_locks(struct cifsFileInfo *cfile)
1084 {
1085 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
1086 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1087
1088 if (cap_unix(tcon->ses) &&
1089 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1090 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1091 return cifs_push_posix_locks(cfile);
1092
1093 return cifs_push_mandatory_locks(cfile);
1094 }
1095
1096 static void
1097 cifs_read_flock(struct file_lock *flock, __u32 *type, int *lock, int *unlock,
1098 bool *wait_flag, struct TCP_Server_Info *server)
1099 {
1100 if (flock->fl_flags & FL_POSIX)
1101 cFYI(1, "Posix");
1102 if (flock->fl_flags & FL_FLOCK)
1103 cFYI(1, "Flock");
1104 if (flock->fl_flags & FL_SLEEP) {
1105 cFYI(1, "Blocking lock");
1106 *wait_flag = true;
1107 }
1108 if (flock->fl_flags & FL_ACCESS)
1109 cFYI(1, "Process suspended by mandatory locking - "
1110 "not implemented yet");
1111 if (flock->fl_flags & FL_LEASE)
1112 cFYI(1, "Lease on file - not implemented yet");
1113 if (flock->fl_flags &
1114 (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
1115 cFYI(1, "Unknown lock flags 0x%x", flock->fl_flags);
1116
1117 *type = server->vals->large_lock_type;
1118 if (flock->fl_type == F_WRLCK) {
1119 cFYI(1, "F_WRLCK ");
1120 *type |= server->vals->exclusive_lock_type;
1121 *lock = 1;
1122 } else if (flock->fl_type == F_UNLCK) {
1123 cFYI(1, "F_UNLCK");
1124 *type |= server->vals->unlock_lock_type;
1125 *unlock = 1;
1126 /* Check if unlock includes more than one lock range */
1127 } else if (flock->fl_type == F_RDLCK) {
1128 cFYI(1, "F_RDLCK");
1129 *type |= server->vals->shared_lock_type;
1130 *lock = 1;
1131 } else if (flock->fl_type == F_EXLCK) {
1132 cFYI(1, "F_EXLCK");
1133 *type |= server->vals->exclusive_lock_type;
1134 *lock = 1;
1135 } else if (flock->fl_type == F_SHLCK) {
1136 cFYI(1, "F_SHLCK");
1137 *type |= server->vals->shared_lock_type;
1138 *lock = 1;
1139 } else
1140 cFYI(1, "Unknown type of lock");
1141 }
1142
1143 static int
1144 cifs_mandatory_lock(unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
1145 __u64 length, __u32 type, int lock, int unlock, bool wait)
1146 {
1147 return CIFSSMBLock(xid, tlink_tcon(cfile->tlink), cfile->fid.netfid,
1148 current->tgid, length, offset, unlock, lock,
1149 (__u8)type, wait, 0);
1150 }
1151
1152 static int
1153 cifs_getlk(struct file *file, struct file_lock *flock, __u32 type,
1154 bool wait_flag, bool posix_lck, unsigned int xid)
1155 {
1156 int rc = 0;
1157 __u64 length = 1 + flock->fl_end - flock->fl_start;
1158 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
1159 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1160 struct TCP_Server_Info *server = tcon->ses->server;
1161 __u16 netfid = cfile->fid.netfid;
1162
1163 if (posix_lck) {
1164 int posix_lock_type;
1165
1166 rc = cifs_posix_lock_test(file, flock);
1167 if (!rc)
1168 return rc;
1169
1170 if (type & server->vals->shared_lock_type)
1171 posix_lock_type = CIFS_RDLCK;
1172 else
1173 posix_lock_type = CIFS_WRLCK;
1174 rc = CIFSSMBPosixLock(xid, tcon, netfid, current->tgid,
1175 flock->fl_start, length, flock,
1176 posix_lock_type, wait_flag);
1177 return rc;
1178 }
1179
1180 rc = cifs_lock_test(cfile, flock->fl_start, length, type, flock);
1181 if (!rc)
1182 return rc;
1183
1184 /* BB we could chain these into one lock request BB */
1185 rc = cifs_mandatory_lock(xid, cfile, flock->fl_start, length, type,
1186 1, 0, false);
1187 if (rc == 0) {
1188 rc = cifs_mandatory_lock(xid, cfile, flock->fl_start, length,
1189 type, 0, 1, false);
1190 flock->fl_type = F_UNLCK;
1191 if (rc != 0)
1192 cERROR(1, "Error unlocking previously locked "
1193 "range %d during test of lock", rc);
1194 return 0;
1195 }
1196
1197 if (type & server->vals->shared_lock_type) {
1198 flock->fl_type = F_WRLCK;
1199 return 0;
1200 }
1201
1202 rc = cifs_mandatory_lock(xid, cfile, flock->fl_start, length,
1203 type | server->vals->shared_lock_type, 1, 0,
1204 false);
1205 if (rc == 0) {
1206 rc = cifs_mandatory_lock(xid, cfile, flock->fl_start, length,
1207 type | server->vals->shared_lock_type,
1208 0, 1, false);
1209 flock->fl_type = F_RDLCK;
1210 if (rc != 0)
1211 cERROR(1, "Error unlocking previously locked "
1212 "range %d during test of lock", rc);
1213 } else
1214 flock->fl_type = F_WRLCK;
1215
1216 return 0;
1217 }
1218
1219 static void
1220 cifs_move_llist(struct list_head *source, struct list_head *dest)
1221 {
1222 struct list_head *li, *tmp;
1223 list_for_each_safe(li, tmp, source)
1224 list_move(li, dest);
1225 }
1226
1227 static void
1228 cifs_free_llist(struct list_head *llist)
1229 {
1230 struct cifsLockInfo *li, *tmp;
1231 list_for_each_entry_safe(li, tmp, llist, llist) {
1232 cifs_del_lock_waiters(li);
1233 list_del(&li->llist);
1234 kfree(li);
1235 }
1236 }
1237
1238 static int
1239 cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
1240 unsigned int xid)
1241 {
1242 int rc = 0, stored_rc;
1243 int types[] = {LOCKING_ANDX_LARGE_FILES,
1244 LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES};
1245 unsigned int i;
1246 unsigned int max_num, num, max_buf;
1247 LOCKING_ANDX_RANGE *buf, *cur;
1248 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1249 struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
1250 struct cifsLockInfo *li, *tmp;
1251 __u64 length = 1 + flock->fl_end - flock->fl_start;
1252 struct list_head tmp_llist;
1253
1254 INIT_LIST_HEAD(&tmp_llist);
1255
1256 /*
1257 * Accessing maxBuf is racy with cifs_reconnect - need to store value
1258 * and check it for zero before using.
1259 */
1260 max_buf = tcon->ses->server->maxBuf;
1261 if (!max_buf)
1262 return -EINVAL;
1263
1264 max_num = (max_buf - sizeof(struct smb_hdr)) /
1265 sizeof(LOCKING_ANDX_RANGE);
1266 buf = kzalloc(max_num * sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
1267 if (!buf)
1268 return -ENOMEM;
1269
1270 mutex_lock(&cinode->lock_mutex);
1271 for (i = 0; i < 2; i++) {
1272 cur = buf;
1273 num = 0;
1274 list_for_each_entry_safe(li, tmp, &cfile->llist, llist) {
1275 if (flock->fl_start > li->offset ||
1276 (flock->fl_start + length) <
1277 (li->offset + li->length))
1278 continue;
1279 if (current->tgid != li->pid)
1280 continue;
1281 if (types[i] != li->type)
1282 continue;
1283 if (cinode->can_cache_brlcks) {
1284 /*
1285 * We can cache brlock requests - simply remove
1286 * a lock from the file's list.
1287 */
1288 list_del(&li->llist);
1289 cifs_del_lock_waiters(li);
1290 kfree(li);
1291 continue;
1292 }
1293 cur->Pid = cpu_to_le16(li->pid);
1294 cur->LengthLow = cpu_to_le32((u32)li->length);
1295 cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
1296 cur->OffsetLow = cpu_to_le32((u32)li->offset);
1297 cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
1298 /*
1299 * We need to save a lock here to let us add it again to
1300 * the file's list if the unlock range request fails on
1301 * the server.
1302 */
1303 list_move(&li->llist, &tmp_llist);
1304 if (++num == max_num) {
1305 stored_rc = cifs_lockv(xid, tcon,
1306 cfile->fid.netfid,
1307 li->type, num, 0, buf);
1308 if (stored_rc) {
1309 /*
1310 * We failed on the unlock range
1311 * request - add all locks from the tmp
1312 * list to the head of the file's list.
1313 */
1314 cifs_move_llist(&tmp_llist,
1315 &cfile->llist);
1316 rc = stored_rc;
1317 } else
1318 /*
1319 * The unlock range request succeed -
1320 * free the tmp list.
1321 */
1322 cifs_free_llist(&tmp_llist);
1323 cur = buf;
1324 num = 0;
1325 } else
1326 cur++;
1327 }
1328 if (num) {
1329 stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
1330 types[i], num, 0, buf);
1331 if (stored_rc) {
1332 cifs_move_llist(&tmp_llist, &cfile->llist);
1333 rc = stored_rc;
1334 } else
1335 cifs_free_llist(&tmp_llist);
1336 }
1337 }
1338
1339 mutex_unlock(&cinode->lock_mutex);
1340 kfree(buf);
1341 return rc;
1342 }
1343
1344 static int
1345 cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
1346 bool wait_flag, bool posix_lck, int lock, int unlock,
1347 unsigned int xid)
1348 {
1349 int rc = 0;
1350 __u64 length = 1 + flock->fl_end - flock->fl_start;
1351 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
1352 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1353 struct TCP_Server_Info *server = tcon->ses->server;
1354 __u16 netfid = cfile->fid.netfid;
1355
1356 if (posix_lck) {
1357 int posix_lock_type;
1358
1359 rc = cifs_posix_lock_set(file, flock);
1360 if (!rc || rc < 0)
1361 return rc;
1362
1363 if (type & server->vals->shared_lock_type)
1364 posix_lock_type = CIFS_RDLCK;
1365 else
1366 posix_lock_type = CIFS_WRLCK;
1367
1368 if (unlock == 1)
1369 posix_lock_type = CIFS_UNLCK;
1370
1371 rc = CIFSSMBPosixLock(xid, tcon, netfid, current->tgid,
1372 flock->fl_start, length, NULL,
1373 posix_lock_type, wait_flag);
1374 goto out;
1375 }
1376
1377 if (lock) {
1378 struct cifsLockInfo *lock;
1379
1380 lock = cifs_lock_init(flock->fl_start, length, type);
1381 if (!lock)
1382 return -ENOMEM;
1383
1384 rc = cifs_lock_add_if(cfile, lock, wait_flag);
1385 if (rc < 0)
1386 kfree(lock);
1387 if (rc <= 0)
1388 goto out;
1389
1390 rc = cifs_mandatory_lock(xid, cfile, flock->fl_start, length,
1391 type, 1, 0, wait_flag);
1392 if (rc) {
1393 kfree(lock);
1394 goto out;
1395 }
1396
1397 cifs_lock_add(cfile, lock);
1398 } else if (unlock)
1399 rc = cifs_unlock_range(cfile, flock, xid);
1400
1401 out:
1402 if (flock->fl_flags & FL_POSIX)
1403 posix_lock_file_wait(file, flock);
1404 return rc;
1405 }
1406
1407 int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
1408 {
1409 int rc, xid;
1410 int lock = 0, unlock = 0;
1411 bool wait_flag = false;
1412 bool posix_lck = false;
1413 struct cifs_sb_info *cifs_sb;
1414 struct cifs_tcon *tcon;
1415 struct cifsInodeInfo *cinode;
1416 struct cifsFileInfo *cfile;
1417 __u16 netfid;
1418 __u32 type;
1419
1420 rc = -EACCES;
1421 xid = get_xid();
1422
1423 cFYI(1, "Lock parm: 0x%x flockflags: 0x%x flocktype: 0x%x start: %lld "
1424 "end: %lld", cmd, flock->fl_flags, flock->fl_type,
1425 flock->fl_start, flock->fl_end);
1426
1427 cfile = (struct cifsFileInfo *)file->private_data;
1428 tcon = tlink_tcon(cfile->tlink);
1429
1430 cifs_read_flock(flock, &type, &lock, &unlock, &wait_flag,
1431 tcon->ses->server);
1432
1433 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1434 netfid = cfile->fid.netfid;
1435 cinode = CIFS_I(file->f_path.dentry->d_inode);
1436
1437 if (cap_unix(tcon->ses) &&
1438 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1439 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1440 posix_lck = true;
1441 /*
1442 * BB add code here to normalize offset and length to account for
1443 * negative length which we can not accept over the wire.
1444 */
1445 if (IS_GETLK(cmd)) {
1446 rc = cifs_getlk(file, flock, type, wait_flag, posix_lck, xid);
1447 free_xid(xid);
1448 return rc;
1449 }
1450
1451 if (!lock && !unlock) {
1452 /*
1453 * if no lock or unlock then nothing to do since we do not
1454 * know what it is
1455 */
1456 free_xid(xid);
1457 return -EOPNOTSUPP;
1458 }
1459
1460 rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock,
1461 xid);
1462 free_xid(xid);
1463 return rc;
1464 }
1465
1466 /*
1467 * update the file size (if needed) after a write. Should be called with
1468 * the inode->i_lock held
1469 */
1470 void
1471 cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
1472 unsigned int bytes_written)
1473 {
1474 loff_t end_of_write = offset + bytes_written;
1475
1476 if (end_of_write > cifsi->server_eof)
1477 cifsi->server_eof = end_of_write;
1478 }
1479
1480 static ssize_t cifs_write(struct cifsFileInfo *open_file, __u32 pid,
1481 const char *write_data, size_t write_size,
1482 loff_t *poffset)
1483 {
1484 int rc = 0;
1485 unsigned int bytes_written = 0;
1486 unsigned int total_written;
1487 struct cifs_sb_info *cifs_sb;
1488 struct cifs_tcon *pTcon;
1489 unsigned int xid;
1490 struct dentry *dentry = open_file->dentry;
1491 struct cifsInodeInfo *cifsi = CIFS_I(dentry->d_inode);
1492 struct cifs_io_parms io_parms;
1493
1494 cifs_sb = CIFS_SB(dentry->d_sb);
1495
1496 cFYI(1, "write %zd bytes to offset %lld of %s", write_size,
1497 *poffset, dentry->d_name.name);
1498
1499 pTcon = tlink_tcon(open_file->tlink);
1500
1501 xid = get_xid();
1502
1503 for (total_written = 0; write_size > total_written;
1504 total_written += bytes_written) {
1505 rc = -EAGAIN;
1506 while (rc == -EAGAIN) {
1507 struct kvec iov[2];
1508 unsigned int len;
1509
1510 if (open_file->invalidHandle) {
1511 /* we could deadlock if we called
1512 filemap_fdatawait from here so tell
1513 reopen_file not to flush data to
1514 server now */
1515 rc = cifs_reopen_file(open_file, false);
1516 if (rc != 0)
1517 break;
1518 }
1519
1520 len = min((size_t)cifs_sb->wsize,
1521 write_size - total_written);
1522 /* iov[0] is reserved for smb header */
1523 iov[1].iov_base = (char *)write_data + total_written;
1524 iov[1].iov_len = len;
1525 io_parms.netfid = open_file->fid.netfid;
1526 io_parms.pid = pid;
1527 io_parms.tcon = pTcon;
1528 io_parms.offset = *poffset;
1529 io_parms.length = len;
1530 rc = CIFSSMBWrite2(xid, &io_parms, &bytes_written, iov,
1531 1, 0);
1532 }
1533 if (rc || (bytes_written == 0)) {
1534 if (total_written)
1535 break;
1536 else {
1537 free_xid(xid);
1538 return rc;
1539 }
1540 } else {
1541 spin_lock(&dentry->d_inode->i_lock);
1542 cifs_update_eof(cifsi, *poffset, bytes_written);
1543 spin_unlock(&dentry->d_inode->i_lock);
1544 *poffset += bytes_written;
1545 }
1546 }
1547
1548 cifs_stats_bytes_written(pTcon, total_written);
1549
1550 if (total_written > 0) {
1551 spin_lock(&dentry->d_inode->i_lock);
1552 if (*poffset > dentry->d_inode->i_size)
1553 i_size_write(dentry->d_inode, *poffset);
1554 spin_unlock(&dentry->d_inode->i_lock);
1555 }
1556 mark_inode_dirty_sync(dentry->d_inode);
1557 free_xid(xid);
1558 return total_written;
1559 }
1560
1561 struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
1562 bool fsuid_only)
1563 {
1564 struct cifsFileInfo *open_file = NULL;
1565 struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
1566
1567 /* only filter by fsuid on multiuser mounts */
1568 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
1569 fsuid_only = false;
1570
1571 spin_lock(&cifs_file_list_lock);
1572 /* we could simply get the first_list_entry since write-only entries
1573 are always at the end of the list but since the first entry might
1574 have a close pending, we go through the whole list */
1575 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1576 if (fsuid_only && open_file->uid != current_fsuid())
1577 continue;
1578 if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
1579 if (!open_file->invalidHandle) {
1580 /* found a good file */
1581 /* lock it so it will not be closed on us */
1582 cifsFileInfo_get_locked(open_file);
1583 spin_unlock(&cifs_file_list_lock);
1584 return open_file;
1585 } /* else might as well continue, and look for
1586 another, or simply have the caller reopen it
1587 again rather than trying to fix this handle */
1588 } else /* write only file */
1589 break; /* write only files are last so must be done */
1590 }
1591 spin_unlock(&cifs_file_list_lock);
1592 return NULL;
1593 }
1594
1595 struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
1596 bool fsuid_only)
1597 {
1598 struct cifsFileInfo *open_file, *inv_file = NULL;
1599 struct cifs_sb_info *cifs_sb;
1600 bool any_available = false;
1601 int rc;
1602 unsigned int refind = 0;
1603
1604 /* Having a null inode here (because mapping->host was set to zero by
1605 the VFS or MM) should not happen but we had reports of on oops (due to
1606 it being zero) during stress testcases so we need to check for it */
1607
1608 if (cifs_inode == NULL) {
1609 cERROR(1, "Null inode passed to cifs_writeable_file");
1610 dump_stack();
1611 return NULL;
1612 }
1613
1614 cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
1615
1616 /* only filter by fsuid on multiuser mounts */
1617 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
1618 fsuid_only = false;
1619
1620 spin_lock(&cifs_file_list_lock);
1621 refind_writable:
1622 if (refind > MAX_REOPEN_ATT) {
1623 spin_unlock(&cifs_file_list_lock);
1624 return NULL;
1625 }
1626 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1627 if (!any_available && open_file->pid != current->tgid)
1628 continue;
1629 if (fsuid_only && open_file->uid != current_fsuid())
1630 continue;
1631 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
1632 if (!open_file->invalidHandle) {
1633 /* found a good writable file */
1634 cifsFileInfo_get_locked(open_file);
1635 spin_unlock(&cifs_file_list_lock);
1636 return open_file;
1637 } else {
1638 if (!inv_file)
1639 inv_file = open_file;
1640 }
1641 }
1642 }
1643 /* couldn't find useable FH with same pid, try any available */
1644 if (!any_available) {
1645 any_available = true;
1646 goto refind_writable;
1647 }
1648
1649 if (inv_file) {
1650 any_available = false;
1651 cifsFileInfo_get_locked(inv_file);
1652 }
1653
1654 spin_unlock(&cifs_file_list_lock);
1655
1656 if (inv_file) {
1657 rc = cifs_reopen_file(inv_file, false);
1658 if (!rc)
1659 return inv_file;
1660 else {
1661 spin_lock(&cifs_file_list_lock);
1662 list_move_tail(&inv_file->flist,
1663 &cifs_inode->openFileList);
1664 spin_unlock(&cifs_file_list_lock);
1665 cifsFileInfo_put(inv_file);
1666 spin_lock(&cifs_file_list_lock);
1667 ++refind;
1668 goto refind_writable;
1669 }
1670 }
1671
1672 return NULL;
1673 }
1674
1675 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
1676 {
1677 struct address_space *mapping = page->mapping;
1678 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1679 char *write_data;
1680 int rc = -EFAULT;
1681 int bytes_written = 0;
1682 struct inode *inode;
1683 struct cifsFileInfo *open_file;
1684
1685 if (!mapping || !mapping->host)
1686 return -EFAULT;
1687
1688 inode = page->mapping->host;
1689
1690 offset += (loff_t)from;
1691 write_data = kmap(page);
1692 write_data += from;
1693
1694 if ((to > PAGE_CACHE_SIZE) || (from > to)) {
1695 kunmap(page);
1696 return -EIO;
1697 }
1698
1699 /* racing with truncate? */
1700 if (offset > mapping->host->i_size) {
1701 kunmap(page);
1702 return 0; /* don't care */
1703 }
1704
1705 /* check to make sure that we are not extending the file */
1706 if (mapping->host->i_size - offset < (loff_t)to)
1707 to = (unsigned)(mapping->host->i_size - offset);
1708
1709 open_file = find_writable_file(CIFS_I(mapping->host), false);
1710 if (open_file) {
1711 bytes_written = cifs_write(open_file, open_file->pid,
1712 write_data, to - from, &offset);
1713 cifsFileInfo_put(open_file);
1714 /* Does mm or vfs already set times? */
1715 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1716 if ((bytes_written > 0) && (offset))
1717 rc = 0;
1718 else if (bytes_written < 0)
1719 rc = bytes_written;
1720 } else {
1721 cFYI(1, "No writeable filehandles for inode");
1722 rc = -EIO;
1723 }
1724
1725 kunmap(page);
1726 return rc;
1727 }
1728
1729 /*
1730 * Marshal up the iov array, reserving the first one for the header. Also,
1731 * set wdata->bytes.
1732 */
1733 static void
1734 cifs_writepages_marshal_iov(struct kvec *iov, struct cifs_writedata *wdata)
1735 {
1736 int i;
1737 struct inode *inode = wdata->cfile->dentry->d_inode;
1738 loff_t size = i_size_read(inode);
1739
1740 /* marshal up the pages into iov array */
1741 wdata->bytes = 0;
1742 for (i = 0; i < wdata->nr_pages; i++) {
1743 iov[i + 1].iov_len = min(size - page_offset(wdata->pages[i]),
1744 (loff_t)PAGE_CACHE_SIZE);
1745 iov[i + 1].iov_base = kmap(wdata->pages[i]);
1746 wdata->bytes += iov[i + 1].iov_len;
1747 }
1748 }
1749
1750 static int cifs_writepages(struct address_space *mapping,
1751 struct writeback_control *wbc)
1752 {
1753 struct cifs_sb_info *cifs_sb = CIFS_SB(mapping->host->i_sb);
1754 bool done = false, scanned = false, range_whole = false;
1755 pgoff_t end, index;
1756 struct cifs_writedata *wdata;
1757 struct page *page;
1758 int rc = 0;
1759
1760 /*
1761 * If wsize is smaller than the page cache size, default to writing
1762 * one page at a time via cifs_writepage
1763 */
1764 if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1765 return generic_writepages(mapping, wbc);
1766
1767 if (wbc->range_cyclic) {
1768 index = mapping->writeback_index; /* Start from prev offset */
1769 end = -1;
1770 } else {
1771 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1772 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1773 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1774 range_whole = true;
1775 scanned = true;
1776 }
1777 retry:
1778 while (!done && index <= end) {
1779 unsigned int i, nr_pages, found_pages;
1780 pgoff_t next = 0, tofind;
1781 struct page **pages;
1782
1783 tofind = min((cifs_sb->wsize / PAGE_CACHE_SIZE) - 1,
1784 end - index) + 1;
1785
1786 wdata = cifs_writedata_alloc((unsigned int)tofind,
1787 cifs_writev_complete);
1788 if (!wdata) {
1789 rc = -ENOMEM;
1790 break;
1791 }
1792
1793 /*
1794 * find_get_pages_tag seems to return a max of 256 on each
1795 * iteration, so we must call it several times in order to
1796 * fill the array or the wsize is effectively limited to
1797 * 256 * PAGE_CACHE_SIZE.
1798 */
1799 found_pages = 0;
1800 pages = wdata->pages;
1801 do {
1802 nr_pages = find_get_pages_tag(mapping, &index,
1803 PAGECACHE_TAG_DIRTY,
1804 tofind, pages);
1805 found_pages += nr_pages;
1806 tofind -= nr_pages;
1807 pages += nr_pages;
1808 } while (nr_pages && tofind && index <= end);
1809
1810 if (found_pages == 0) {
1811 kref_put(&wdata->refcount, cifs_writedata_release);
1812 break;
1813 }
1814
1815 nr_pages = 0;
1816 for (i = 0; i < found_pages; i++) {
1817 page = wdata->pages[i];
1818 /*
1819 * At this point we hold neither mapping->tree_lock nor
1820 * lock on the page itself: the page may be truncated or
1821 * invalidated (changing page->mapping to NULL), or even
1822 * swizzled back from swapper_space to tmpfs file
1823 * mapping
1824 */
1825
1826 if (nr_pages == 0)
1827 lock_page(page);
1828 else if (!trylock_page(page))
1829 break;
1830
1831 if (unlikely(page->mapping != mapping)) {
1832 unlock_page(page);
1833 break;
1834 }
1835
1836 if (!wbc->range_cyclic && page->index > end) {
1837 done = true;
1838 unlock_page(page);
1839 break;
1840 }
1841
1842 if (next && (page->index != next)) {
1843 /* Not next consecutive page */
1844 unlock_page(page);
1845 break;
1846 }
1847
1848 if (wbc->sync_mode != WB_SYNC_NONE)
1849 wait_on_page_writeback(page);
1850
1851 if (PageWriteback(page) ||
1852 !clear_page_dirty_for_io(page)) {
1853 unlock_page(page);
1854 break;
1855 }
1856
1857 /*
1858 * This actually clears the dirty bit in the radix tree.
1859 * See cifs_writepage() for more commentary.
1860 */
1861 set_page_writeback(page);
1862
1863 if (page_offset(page) >= mapping->host->i_size) {
1864 done = true;
1865 unlock_page(page);
1866 end_page_writeback(page);
1867 break;
1868 }
1869
1870 wdata->pages[i] = page;
1871 next = page->index + 1;
1872 ++nr_pages;
1873 }
1874
1875 /* reset index to refind any pages skipped */
1876 if (nr_pages == 0)
1877 index = wdata->pages[0]->index + 1;
1878
1879 /* put any pages we aren't going to use */
1880 for (i = nr_pages; i < found_pages; i++) {
1881 page_cache_release(wdata->pages[i]);
1882 wdata->pages[i] = NULL;
1883 }
1884
1885 /* nothing to write? */
1886 if (nr_pages == 0) {
1887 kref_put(&wdata->refcount, cifs_writedata_release);
1888 continue;
1889 }
1890
1891 wdata->sync_mode = wbc->sync_mode;
1892 wdata->nr_pages = nr_pages;
1893 wdata->offset = page_offset(wdata->pages[0]);
1894 wdata->marshal_iov = cifs_writepages_marshal_iov;
1895
1896 do {
1897 if (wdata->cfile != NULL)
1898 cifsFileInfo_put(wdata->cfile);
1899 wdata->cfile = find_writable_file(CIFS_I(mapping->host),
1900 false);
1901 if (!wdata->cfile) {
1902 cERROR(1, "No writable handles for inode");
1903 rc = -EBADF;
1904 break;
1905 }
1906 wdata->pid = wdata->cfile->pid;
1907 rc = cifs_async_writev(wdata);
1908 } while (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN);
1909
1910 for (i = 0; i < nr_pages; ++i)
1911 unlock_page(wdata->pages[i]);
1912
1913 /* send failure -- clean up the mess */
1914 if (rc != 0) {
1915 for (i = 0; i < nr_pages; ++i) {
1916 if (rc == -EAGAIN)
1917 redirty_page_for_writepage(wbc,
1918 wdata->pages[i]);
1919 else
1920 SetPageError(wdata->pages[i]);
1921 end_page_writeback(wdata->pages[i]);
1922 page_cache_release(wdata->pages[i]);
1923 }
1924 if (rc != -EAGAIN)
1925 mapping_set_error(mapping, rc);
1926 }
1927 kref_put(&wdata->refcount, cifs_writedata_release);
1928
1929 wbc->nr_to_write -= nr_pages;
1930 if (wbc->nr_to_write <= 0)
1931 done = true;
1932
1933 index = next;
1934 }
1935
1936 if (!scanned && !done) {
1937 /*
1938 * We hit the last page and there is more work to be done: wrap
1939 * back to the start of the file
1940 */
1941 scanned = true;
1942 index = 0;
1943 goto retry;
1944 }
1945
1946 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1947 mapping->writeback_index = index;
1948
1949 return rc;
1950 }
1951
1952 static int
1953 cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
1954 {
1955 int rc;
1956 unsigned int xid;
1957
1958 xid = get_xid();
1959 /* BB add check for wbc flags */
1960 page_cache_get(page);
1961 if (!PageUptodate(page))
1962 cFYI(1, "ppw - page not up to date");
1963
1964 /*
1965 * Set the "writeback" flag, and clear "dirty" in the radix tree.
1966 *
1967 * A writepage() implementation always needs to do either this,
1968 * or re-dirty the page with "redirty_page_for_writepage()" in
1969 * the case of a failure.
1970 *
1971 * Just unlocking the page will cause the radix tree tag-bits
1972 * to fail to update with the state of the page correctly.
1973 */
1974 set_page_writeback(page);
1975 retry_write:
1976 rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1977 if (rc == -EAGAIN && wbc->sync_mode == WB_SYNC_ALL)
1978 goto retry_write;
1979 else if (rc == -EAGAIN)
1980 redirty_page_for_writepage(wbc, page);
1981 else if (rc != 0)
1982 SetPageError(page);
1983 else
1984 SetPageUptodate(page);
1985 end_page_writeback(page);
1986 page_cache_release(page);
1987 free_xid(xid);
1988 return rc;
1989 }
1990
1991 static int cifs_writepage(struct page *page, struct writeback_control *wbc)
1992 {
1993 int rc = cifs_writepage_locked(page, wbc);
1994 unlock_page(page);
1995 return rc;
1996 }
1997
1998 static int cifs_write_end(struct file *file, struct address_space *mapping,
1999 loff_t pos, unsigned len, unsigned copied,
2000 struct page *page, void *fsdata)
2001 {
2002 int rc;
2003 struct inode *inode = mapping->host;
2004 struct cifsFileInfo *cfile = file->private_data;
2005 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
2006 __u32 pid;
2007
2008 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2009 pid = cfile->pid;
2010 else
2011 pid = current->tgid;
2012
2013 cFYI(1, "write_end for page %p from pos %lld with %d bytes",
2014 page, pos, copied);
2015
2016 if (PageChecked(page)) {
2017 if (copied == len)
2018 SetPageUptodate(page);
2019 ClearPageChecked(page);
2020 } else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
2021 SetPageUptodate(page);
2022
2023 if (!PageUptodate(page)) {
2024 char *page_data;
2025 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
2026 unsigned int xid;
2027
2028 xid = get_xid();
2029 /* this is probably better than directly calling
2030 partialpage_write since in this function the file handle is
2031 known which we might as well leverage */
2032 /* BB check if anything else missing out of ppw
2033 such as updating last write time */
2034 page_data = kmap(page);
2035 rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
2036 /* if (rc < 0) should we set writebehind rc? */
2037 kunmap(page);
2038
2039 free_xid(xid);
2040 } else {
2041 rc = copied;
2042 pos += copied;
2043 set_page_dirty(page);
2044 }
2045
2046 if (rc > 0) {
2047 spin_lock(&inode->i_lock);
2048 if (pos > inode->i_size)
2049 i_size_write(inode, pos);
2050 spin_unlock(&inode->i_lock);
2051 }
2052
2053 unlock_page(page);
2054 page_cache_release(page);
2055
2056 return rc;
2057 }
2058
2059 int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
2060 int datasync)
2061 {
2062 unsigned int xid;
2063 int rc = 0;
2064 struct cifs_tcon *tcon;
2065 struct cifsFileInfo *smbfile = file->private_data;
2066 struct inode *inode = file->f_path.dentry->d_inode;
2067 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2068
2069 rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
2070 if (rc)
2071 return rc;
2072 mutex_lock(&inode->i_mutex);
2073
2074 xid = get_xid();
2075
2076 cFYI(1, "Sync file - name: %s datasync: 0x%x",
2077 file->f_path.dentry->d_name.name, datasync);
2078
2079 if (!CIFS_I(inode)->clientCanCacheRead) {
2080 rc = cifs_invalidate_mapping(inode);
2081 if (rc) {
2082 cFYI(1, "rc: %d during invalidate phase", rc);
2083 rc = 0; /* don't care about it in fsync */
2084 }
2085 }
2086
2087 tcon = tlink_tcon(smbfile->tlink);
2088 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
2089 rc = CIFSSMBFlush(xid, tcon, smbfile->fid.netfid);
2090
2091 free_xid(xid);
2092 mutex_unlock(&inode->i_mutex);
2093 return rc;
2094 }
2095
2096 int cifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2097 {
2098 unsigned int xid;
2099 int rc = 0;
2100 struct cifs_tcon *tcon;
2101 struct cifsFileInfo *smbfile = file->private_data;
2102 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
2103 struct inode *inode = file->f_mapping->host;
2104
2105 rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
2106 if (rc)
2107 return rc;
2108 mutex_lock(&inode->i_mutex);
2109
2110 xid = get_xid();
2111
2112 cFYI(1, "Sync file - name: %s datasync: 0x%x",
2113 file->f_path.dentry->d_name.name, datasync);
2114
2115 tcon = tlink_tcon(smbfile->tlink);
2116 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
2117 rc = CIFSSMBFlush(xid, tcon, smbfile->fid.netfid);
2118
2119 free_xid(xid);
2120 mutex_unlock(&inode->i_mutex);
2121 return rc;
2122 }
2123
2124 /*
2125 * As file closes, flush all cached write data for this inode checking
2126 * for write behind errors.
2127 */
2128 int cifs_flush(struct file *file, fl_owner_t id)
2129 {
2130 struct inode *inode = file->f_path.dentry->d_inode;
2131 int rc = 0;
2132
2133 if (file->f_mode & FMODE_WRITE)
2134 rc = filemap_write_and_wait(inode->i_mapping);
2135
2136 cFYI(1, "Flush inode %p file %p rc %d", inode, file, rc);
2137
2138 return rc;
2139 }
2140
2141 static int
2142 cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
2143 {
2144 int rc = 0;
2145 unsigned long i;
2146
2147 for (i = 0; i < num_pages; i++) {
2148 pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
2149 if (!pages[i]) {
2150 /*
2151 * save number of pages we have already allocated and
2152 * return with ENOMEM error
2153 */
2154 num_pages = i;
2155 rc = -ENOMEM;
2156 break;
2157 }
2158 }
2159
2160 if (rc) {
2161 for (i = 0; i < num_pages; i++)
2162 put_page(pages[i]);
2163 }
2164 return rc;
2165 }
2166
2167 static inline
2168 size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
2169 {
2170 size_t num_pages;
2171 size_t clen;
2172
2173 clen = min_t(const size_t, len, wsize);
2174 num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
2175
2176 if (cur_len)
2177 *cur_len = clen;
2178
2179 return num_pages;
2180 }
2181
2182 static void
2183 cifs_uncached_marshal_iov(struct kvec *iov, struct cifs_writedata *wdata)
2184 {
2185 int i;
2186 size_t bytes = wdata->bytes;
2187
2188 /* marshal up the pages into iov array */
2189 for (i = 0; i < wdata->nr_pages; i++) {
2190 iov[i + 1].iov_len = min_t(size_t, bytes, PAGE_SIZE);
2191 iov[i + 1].iov_base = kmap(wdata->pages[i]);
2192 bytes -= iov[i + 1].iov_len;
2193 }
2194 }
2195
2196 static void
2197 cifs_uncached_writev_complete(struct work_struct *work)
2198 {
2199 int i;
2200 struct cifs_writedata *wdata = container_of(work,
2201 struct cifs_writedata, work);
2202 struct inode *inode = wdata->cfile->dentry->d_inode;
2203 struct cifsInodeInfo *cifsi = CIFS_I(inode);
2204
2205 spin_lock(&inode->i_lock);
2206 cifs_update_eof(cifsi, wdata->offset, wdata->bytes);
2207 if (cifsi->server_eof > inode->i_size)
2208 i_size_write(inode, cifsi->server_eof);
2209 spin_unlock(&inode->i_lock);
2210
2211 complete(&wdata->done);
2212
2213 if (wdata->result != -EAGAIN) {
2214 for (i = 0; i < wdata->nr_pages; i++)
2215 put_page(wdata->pages[i]);
2216 }
2217
2218 kref_put(&wdata->refcount, cifs_writedata_release);
2219 }
2220
2221 /* attempt to send write to server, retry on any -EAGAIN errors */
2222 static int
2223 cifs_uncached_retry_writev(struct cifs_writedata *wdata)
2224 {
2225 int rc;
2226
2227 do {
2228 if (wdata->cfile->invalidHandle) {
2229 rc = cifs_reopen_file(wdata->cfile, false);
2230 if (rc != 0)
2231 continue;
2232 }
2233 rc = cifs_async_writev(wdata);
2234 } while (rc == -EAGAIN);
2235
2236 return rc;
2237 }
2238
2239 static ssize_t
2240 cifs_iovec_write(struct file *file, const struct iovec *iov,
2241 unsigned long nr_segs, loff_t *poffset)
2242 {
2243 unsigned long nr_pages, i;
2244 size_t copied, len, cur_len;
2245 ssize_t total_written = 0;
2246 loff_t offset;
2247 struct iov_iter it;
2248 struct cifsFileInfo *open_file;
2249 struct cifs_tcon *tcon;
2250 struct cifs_sb_info *cifs_sb;
2251 struct cifs_writedata *wdata, *tmp;
2252 struct list_head wdata_list;
2253 int rc;
2254 pid_t pid;
2255
2256 len = iov_length(iov, nr_segs);
2257 if (!len)
2258 return 0;
2259
2260 rc = generic_write_checks(file, poffset, &len, 0);
2261 if (rc)
2262 return rc;
2263
2264 INIT_LIST_HEAD(&wdata_list);
2265 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
2266 open_file = file->private_data;
2267 tcon = tlink_tcon(open_file->tlink);
2268 offset = *poffset;
2269
2270 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2271 pid = open_file->pid;
2272 else
2273 pid = current->tgid;
2274
2275 iov_iter_init(&it, iov, nr_segs, len, 0);
2276 do {
2277 size_t save_len;
2278
2279 nr_pages = get_numpages(cifs_sb->wsize, len, &cur_len);
2280 wdata = cifs_writedata_alloc(nr_pages,
2281 cifs_uncached_writev_complete);
2282 if (!wdata) {
2283 rc = -ENOMEM;
2284 break;
2285 }
2286
2287 rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
2288 if (rc) {
2289 kfree(wdata);
2290 break;
2291 }
2292
2293 save_len = cur_len;
2294 for (i = 0; i < nr_pages; i++) {
2295 copied = min_t(const size_t, cur_len, PAGE_SIZE);
2296 copied = iov_iter_copy_from_user(wdata->pages[i], &it,
2297 0, copied);
2298 cur_len -= copied;
2299 iov_iter_advance(&it, copied);
2300 }
2301 cur_len = save_len - cur_len;
2302
2303 wdata->sync_mode = WB_SYNC_ALL;
2304 wdata->nr_pages = nr_pages;
2305 wdata->offset = (__u64)offset;
2306 wdata->cfile = cifsFileInfo_get(open_file);
2307 wdata->pid = pid;
2308 wdata->bytes = cur_len;
2309 wdata->marshal_iov = cifs_uncached_marshal_iov;
2310 rc = cifs_uncached_retry_writev(wdata);
2311 if (rc) {
2312 kref_put(&wdata->refcount, cifs_writedata_release);
2313 break;
2314 }
2315
2316 list_add_tail(&wdata->list, &wdata_list);
2317 offset += cur_len;
2318 len -= cur_len;
2319 } while (len > 0);
2320
2321 /*
2322 * If at least one write was successfully sent, then discard any rc
2323 * value from the later writes. If the other write succeeds, then
2324 * we'll end up returning whatever was written. If it fails, then
2325 * we'll get a new rc value from that.
2326 */
2327 if (!list_empty(&wdata_list))
2328 rc = 0;
2329
2330 /*
2331 * Wait for and collect replies for any successful sends in order of
2332 * increasing offset. Once an error is hit or we get a fatal signal
2333 * while waiting, then return without waiting for any more replies.
2334 */
2335 restart_loop:
2336 list_for_each_entry_safe(wdata, tmp, &wdata_list, list) {
2337 if (!rc) {
2338 /* FIXME: freezable too? */
2339 rc = wait_for_completion_killable(&wdata->done);
2340 if (rc)
2341 rc = -EINTR;
2342 else if (wdata->result)
2343 rc = wdata->result;
2344 else
2345 total_written += wdata->bytes;
2346
2347 /* resend call if it's a retryable error */
2348 if (rc == -EAGAIN) {
2349 rc = cifs_uncached_retry_writev(wdata);
2350 goto restart_loop;
2351 }
2352 }
2353 list_del_init(&wdata->list);
2354 kref_put(&wdata->refcount, cifs_writedata_release);
2355 }
2356
2357 if (total_written > 0)
2358 *poffset += total_written;
2359
2360 cifs_stats_bytes_written(tcon, total_written);
2361 return total_written ? total_written : (ssize_t)rc;
2362 }
2363
2364 ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
2365 unsigned long nr_segs, loff_t pos)
2366 {
2367 ssize_t written;
2368 struct inode *inode;
2369
2370 inode = iocb->ki_filp->f_path.dentry->d_inode;
2371
2372 /*
2373 * BB - optimize the way when signing is disabled. We can drop this
2374 * extra memory-to-memory copying and use iovec buffers for constructing
2375 * write request.
2376 */
2377
2378 written = cifs_iovec_write(iocb->ki_filp, iov, nr_segs, &pos);
2379 if (written > 0) {
2380 CIFS_I(inode)->invalid_mapping = true;
2381 iocb->ki_pos = pos;
2382 }
2383
2384 return written;
2385 }
2386
2387 ssize_t cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
2388 unsigned long nr_segs, loff_t pos)
2389 {
2390 struct inode *inode;
2391
2392 inode = iocb->ki_filp->f_path.dentry->d_inode;
2393
2394 if (CIFS_I(inode)->clientCanCacheAll)
2395 return generic_file_aio_write(iocb, iov, nr_segs, pos);
2396
2397 /*
2398 * In strict cache mode we need to write the data to the server exactly
2399 * from the pos to pos+len-1 rather than flush all affected pages
2400 * because it may cause a error with mandatory locks on these pages but
2401 * not on the region from pos to ppos+len-1.
2402 */
2403
2404 return cifs_user_writev(iocb, iov, nr_segs, pos);
2405 }
2406
2407 static struct cifs_readdata *
2408 cifs_readdata_alloc(unsigned int nr_vecs, work_func_t complete)
2409 {
2410 struct cifs_readdata *rdata;
2411
2412 rdata = kzalloc(sizeof(*rdata) +
2413 sizeof(struct kvec) * nr_vecs, GFP_KERNEL);
2414 if (rdata != NULL) {
2415 kref_init(&rdata->refcount);
2416 INIT_LIST_HEAD(&rdata->list);
2417 init_completion(&rdata->done);
2418 INIT_WORK(&rdata->work, complete);
2419 INIT_LIST_HEAD(&rdata->pages);
2420 }
2421 return rdata;
2422 }
2423
2424 void
2425 cifs_readdata_release(struct kref *refcount)
2426 {
2427 struct cifs_readdata *rdata = container_of(refcount,
2428 struct cifs_readdata, refcount);
2429
2430 if (rdata->cfile)
2431 cifsFileInfo_put(rdata->cfile);
2432
2433 kfree(rdata);
2434 }
2435
2436 static int
2437 cifs_read_allocate_pages(struct list_head *list, unsigned int npages)
2438 {
2439 int rc = 0;
2440 struct page *page, *tpage;
2441 unsigned int i;
2442
2443 for (i = 0; i < npages; i++) {
2444 page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
2445 if (!page) {
2446 rc = -ENOMEM;
2447 break;
2448 }
2449 list_add(&page->lru, list);
2450 }
2451
2452 if (rc) {
2453 list_for_each_entry_safe(page, tpage, list, lru) {
2454 list_del(&page->lru);
2455 put_page(page);
2456 }
2457 }
2458 return rc;
2459 }
2460
2461 static void
2462 cifs_uncached_readdata_release(struct kref *refcount)
2463 {
2464 struct page *page, *tpage;
2465 struct cifs_readdata *rdata = container_of(refcount,
2466 struct cifs_readdata, refcount);
2467
2468 list_for_each_entry_safe(page, tpage, &rdata->pages, lru) {
2469 list_del(&page->lru);
2470 put_page(page);
2471 }
2472 cifs_readdata_release(refcount);
2473 }
2474
2475 static int
2476 cifs_retry_async_readv(struct cifs_readdata *rdata)
2477 {
2478 int rc;
2479
2480 do {
2481 if (rdata->cfile->invalidHandle) {
2482 rc = cifs_reopen_file(rdata->cfile, true);
2483 if (rc != 0)
2484 continue;
2485 }
2486 rc = cifs_async_readv(rdata);
2487 } while (rc == -EAGAIN);
2488
2489 return rc;
2490 }
2491
2492 /**
2493 * cifs_readdata_to_iov - copy data from pages in response to an iovec
2494 * @rdata: the readdata response with list of pages holding data
2495 * @iov: vector in which we should copy the data
2496 * @nr_segs: number of segments in vector
2497 * @offset: offset into file of the first iovec
2498 * @copied: used to return the amount of data copied to the iov
2499 *
2500 * This function copies data from a list of pages in a readdata response into
2501 * an array of iovecs. It will first calculate where the data should go
2502 * based on the info in the readdata and then copy the data into that spot.
2503 */
2504 static ssize_t
2505 cifs_readdata_to_iov(struct cifs_readdata *rdata, const struct iovec *iov,
2506 unsigned long nr_segs, loff_t offset, ssize_t *copied)
2507 {
2508 int rc = 0;
2509 struct iov_iter ii;
2510 size_t pos = rdata->offset - offset;
2511 struct page *page, *tpage;
2512 ssize_t remaining = rdata->bytes;
2513 unsigned char *pdata;
2514
2515 /* set up iov_iter and advance to the correct offset */
2516 iov_iter_init(&ii, iov, nr_segs, iov_length(iov, nr_segs), 0);
2517 iov_iter_advance(&ii, pos);
2518
2519 *copied = 0;
2520 list_for_each_entry_safe(page, tpage, &rdata->pages, lru) {
2521 ssize_t copy;
2522
2523 /* copy a whole page or whatever's left */
2524 copy = min_t(ssize_t, remaining, PAGE_SIZE);
2525
2526 /* ...but limit it to whatever space is left in the iov */
2527 copy = min_t(ssize_t, copy, iov_iter_count(&ii));
2528
2529 /* go while there's data to be copied and no errors */
2530 if (copy && !rc) {
2531 pdata = kmap(page);
2532 rc = memcpy_toiovecend(ii.iov, pdata, ii.iov_offset,
2533 (int)copy);
2534 kunmap(page);
2535 if (!rc) {
2536 *copied += copy;
2537 remaining -= copy;
2538 iov_iter_advance(&ii, copy);
2539 }
2540 }
2541
2542 list_del(&page->lru);
2543 put_page(page);
2544 }
2545
2546 return rc;
2547 }
2548
2549 static void
2550 cifs_uncached_readv_complete(struct work_struct *work)
2551 {
2552 struct cifs_readdata *rdata = container_of(work,
2553 struct cifs_readdata, work);
2554
2555 /* if the result is non-zero then the pages weren't kmapped */
2556 if (rdata->result == 0) {
2557 struct page *page;
2558
2559 list_for_each_entry(page, &rdata->pages, lru)
2560 kunmap(page);
2561 }
2562
2563 complete(&rdata->done);
2564 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
2565 }
2566
2567 static int
2568 cifs_uncached_read_marshal_iov(struct cifs_readdata *rdata,
2569 unsigned int remaining)
2570 {
2571 int len = 0;
2572 struct page *page, *tpage;
2573
2574 rdata->nr_iov = 1;
2575 list_for_each_entry_safe(page, tpage, &rdata->pages, lru) {
2576 if (remaining >= PAGE_SIZE) {
2577 /* enough data to fill the page */
2578 rdata->iov[rdata->nr_iov].iov_base = kmap(page);
2579 rdata->iov[rdata->nr_iov].iov_len = PAGE_SIZE;
2580 cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu",
2581 rdata->nr_iov, page->index,
2582 rdata->iov[rdata->nr_iov].iov_base,
2583 rdata->iov[rdata->nr_iov].iov_len);
2584 ++rdata->nr_iov;
2585 len += PAGE_SIZE;
2586 remaining -= PAGE_SIZE;
2587 } else if (remaining > 0) {
2588 /* enough for partial page, fill and zero the rest */
2589 rdata->iov[rdata->nr_iov].iov_base = kmap(page);
2590 rdata->iov[rdata->nr_iov].iov_len = remaining;
2591 cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu",
2592 rdata->nr_iov, page->index,
2593 rdata->iov[rdata->nr_iov].iov_base,
2594 rdata->iov[rdata->nr_iov].iov_len);
2595 memset(rdata->iov[rdata->nr_iov].iov_base + remaining,
2596 '\0', PAGE_SIZE - remaining);
2597 ++rdata->nr_iov;
2598 len += remaining;
2599 remaining = 0;
2600 } else {
2601 /* no need to hold page hostage */
2602 list_del(&page->lru);
2603 put_page(page);
2604 }
2605 }
2606
2607 return len;
2608 }
2609
2610 static ssize_t
2611 cifs_iovec_read(struct file *file, const struct iovec *iov,
2612 unsigned long nr_segs, loff_t *poffset)
2613 {
2614 ssize_t rc;
2615 size_t len, cur_len;
2616 ssize_t total_read = 0;
2617 loff_t offset = *poffset;
2618 unsigned int npages;
2619 struct cifs_sb_info *cifs_sb;
2620 struct cifs_tcon *tcon;
2621 struct cifsFileInfo *open_file;
2622 struct cifs_readdata *rdata, *tmp;
2623 struct list_head rdata_list;
2624 pid_t pid;
2625
2626 if (!nr_segs)
2627 return 0;
2628
2629 len = iov_length(iov, nr_segs);
2630 if (!len)
2631 return 0;
2632
2633 INIT_LIST_HEAD(&rdata_list);
2634 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
2635 open_file = file->private_data;
2636 tcon = tlink_tcon(open_file->tlink);
2637
2638 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2639 pid = open_file->pid;
2640 else
2641 pid = current->tgid;
2642
2643 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
2644 cFYI(1, "attempting read on write only file instance");
2645
2646 do {
2647 cur_len = min_t(const size_t, len - total_read, cifs_sb->rsize);
2648 npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
2649
2650 /* allocate a readdata struct */
2651 rdata = cifs_readdata_alloc(npages,
2652 cifs_uncached_readv_complete);
2653 if (!rdata) {
2654 rc = -ENOMEM;
2655 goto error;
2656 }
2657
2658 rc = cifs_read_allocate_pages(&rdata->pages, npages);
2659 if (rc)
2660 goto error;
2661
2662 rdata->cfile = cifsFileInfo_get(open_file);
2663 rdata->offset = offset;
2664 rdata->bytes = cur_len;
2665 rdata->pid = pid;
2666 rdata->marshal_iov = cifs_uncached_read_marshal_iov;
2667
2668 rc = cifs_retry_async_readv(rdata);
2669 error:
2670 if (rc) {
2671 kref_put(&rdata->refcount,
2672 cifs_uncached_readdata_release);
2673 break;
2674 }
2675
2676 list_add_tail(&rdata->list, &rdata_list);
2677 offset += cur_len;
2678 len -= cur_len;
2679 } while (len > 0);
2680
2681 /* if at least one read request send succeeded, then reset rc */
2682 if (!list_empty(&rdata_list))
2683 rc = 0;
2684
2685 /* the loop below should proceed in the order of increasing offsets */
2686 restart_loop:
2687 list_for_each_entry_safe(rdata, tmp, &rdata_list, list) {
2688 if (!rc) {
2689 ssize_t copied;
2690
2691 /* FIXME: freezable sleep too? */
2692 rc = wait_for_completion_killable(&rdata->done);
2693 if (rc)
2694 rc = -EINTR;
2695 else if (rdata->result)
2696 rc = rdata->result;
2697 else {
2698 rc = cifs_readdata_to_iov(rdata, iov,
2699 nr_segs, *poffset,
2700 &copied);
2701 total_read += copied;
2702 }
2703
2704 /* resend call if it's a retryable error */
2705 if (rc == -EAGAIN) {
2706 rc = cifs_retry_async_readv(rdata);
2707 goto restart_loop;
2708 }
2709 }
2710 list_del_init(&rdata->list);
2711 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
2712 }
2713
2714 cifs_stats_bytes_read(tcon, total_read);
2715 *poffset += total_read;
2716
2717 return total_read ? total_read : rc;
2718 }
2719
2720 ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
2721 unsigned long nr_segs, loff_t pos)
2722 {
2723 ssize_t read;
2724
2725 read = cifs_iovec_read(iocb->ki_filp, iov, nr_segs, &pos);
2726 if (read > 0)
2727 iocb->ki_pos = pos;
2728
2729 return read;
2730 }
2731
2732 ssize_t cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
2733 unsigned long nr_segs, loff_t pos)
2734 {
2735 struct inode *inode;
2736
2737 inode = iocb->ki_filp->f_path.dentry->d_inode;
2738
2739 if (CIFS_I(inode)->clientCanCacheRead)
2740 return generic_file_aio_read(iocb, iov, nr_segs, pos);
2741
2742 /*
2743 * In strict cache mode we need to read from the server all the time
2744 * if we don't have level II oplock because the server can delay mtime
2745 * change - so we can't make a decision about inode invalidating.
2746 * And we can also fail with pagereading if there are mandatory locks
2747 * on pages affected by this read but not on the region from pos to
2748 * pos+len-1.
2749 */
2750
2751 return cifs_user_readv(iocb, iov, nr_segs, pos);
2752 }
2753
2754 static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
2755 loff_t *poffset)
2756 {
2757 int rc = -EACCES;
2758 unsigned int bytes_read = 0;
2759 unsigned int total_read;
2760 unsigned int current_read_size;
2761 unsigned int rsize;
2762 struct cifs_sb_info *cifs_sb;
2763 struct cifs_tcon *tcon;
2764 unsigned int xid;
2765 char *current_offset;
2766 struct cifsFileInfo *open_file;
2767 struct cifs_io_parms io_parms;
2768 int buf_type = CIFS_NO_BUFFER;
2769 __u32 pid;
2770
2771 xid = get_xid();
2772 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
2773
2774 /* FIXME: set up handlers for larger reads and/or convert to async */
2775 rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
2776
2777 if (file->private_data == NULL) {
2778 rc = -EBADF;
2779 free_xid(xid);
2780 return rc;
2781 }
2782 open_file = file->private_data;
2783 tcon = tlink_tcon(open_file->tlink);
2784
2785 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2786 pid = open_file->pid;
2787 else
2788 pid = current->tgid;
2789
2790 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
2791 cFYI(1, "attempting read on write only file instance");
2792
2793 for (total_read = 0, current_offset = read_data;
2794 read_size > total_read;
2795 total_read += bytes_read, current_offset += bytes_read) {
2796 current_read_size = min_t(uint, read_size - total_read, rsize);
2797 /*
2798 * For windows me and 9x we do not want to request more than it
2799 * negotiated since it will refuse the read then.
2800 */
2801 if ((tcon->ses) && !(tcon->ses->capabilities &
2802 tcon->ses->server->vals->cap_large_files)) {
2803 current_read_size = min_t(uint, current_read_size,
2804 CIFSMaxBufSize);
2805 }
2806 rc = -EAGAIN;
2807 while (rc == -EAGAIN) {
2808 if (open_file->invalidHandle) {
2809 rc = cifs_reopen_file(open_file, true);
2810 if (rc != 0)
2811 break;
2812 }
2813 io_parms.netfid = open_file->fid.netfid;
2814 io_parms.pid = pid;
2815 io_parms.tcon = tcon;
2816 io_parms.offset = *poffset;
2817 io_parms.length = current_read_size;
2818 rc = CIFSSMBRead(xid, &io_parms, &bytes_read,
2819 &current_offset, &buf_type);
2820 }
2821 if (rc || (bytes_read == 0)) {
2822 if (total_read) {
2823 break;
2824 } else {
2825 free_xid(xid);
2826 return rc;
2827 }
2828 } else {
2829 cifs_stats_bytes_read(tcon, total_read);
2830 *poffset += bytes_read;
2831 }
2832 }
2833 free_xid(xid);
2834 return total_read;
2835 }
2836
2837 /*
2838 * If the page is mmap'ed into a process' page tables, then we need to make
2839 * sure that it doesn't change while being written back.
2840 */
2841 static int
2842 cifs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
2843 {
2844 struct page *page = vmf->page;
2845
2846 lock_page(page);
2847 return VM_FAULT_LOCKED;
2848 }
2849
2850 static struct vm_operations_struct cifs_file_vm_ops = {
2851 .fault = filemap_fault,
2852 .page_mkwrite = cifs_page_mkwrite,
2853 };
2854
2855 int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
2856 {
2857 int rc, xid;
2858 struct inode *inode = file->f_path.dentry->d_inode;
2859
2860 xid = get_xid();
2861
2862 if (!CIFS_I(inode)->clientCanCacheRead) {
2863 rc = cifs_invalidate_mapping(inode);
2864 if (rc)
2865 return rc;
2866 }
2867
2868 rc = generic_file_mmap(file, vma);
2869 if (rc == 0)
2870 vma->vm_ops = &cifs_file_vm_ops;
2871 free_xid(xid);
2872 return rc;
2873 }
2874
2875 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
2876 {
2877 int rc, xid;
2878
2879 xid = get_xid();
2880 rc = cifs_revalidate_file(file);
2881 if (rc) {
2882 cFYI(1, "Validation prior to mmap failed, error=%d", rc);
2883 free_xid(xid);
2884 return rc;
2885 }
2886 rc = generic_file_mmap(file, vma);
2887 if (rc == 0)
2888 vma->vm_ops = &cifs_file_vm_ops;
2889 free_xid(xid);
2890 return rc;
2891 }
2892
2893 static void
2894 cifs_readv_complete(struct work_struct *work)
2895 {
2896 struct cifs_readdata *rdata = container_of(work,
2897 struct cifs_readdata, work);
2898 struct page *page, *tpage;
2899
2900 list_for_each_entry_safe(page, tpage, &rdata->pages, lru) {
2901 list_del(&page->lru);
2902 lru_cache_add_file(page);
2903
2904 if (rdata->result == 0) {
2905 kunmap(page);
2906 flush_dcache_page(page);
2907 SetPageUptodate(page);
2908 }
2909
2910 unlock_page(page);
2911
2912 if (rdata->result == 0)
2913 cifs_readpage_to_fscache(rdata->mapping->host, page);
2914
2915 page_cache_release(page);
2916 }
2917 kref_put(&rdata->refcount, cifs_readdata_release);
2918 }
2919
2920 static int
2921 cifs_readpages_marshal_iov(struct cifs_readdata *rdata, unsigned int remaining)
2922 {
2923 int len = 0;
2924 struct page *page, *tpage;
2925 u64 eof;
2926 pgoff_t eof_index;
2927
2928 /* determine the eof that the server (probably) has */
2929 eof = CIFS_I(rdata->mapping->host)->server_eof;
2930 eof_index = eof ? (eof - 1) >> PAGE_CACHE_SHIFT : 0;
2931 cFYI(1, "eof=%llu eof_index=%lu", eof, eof_index);
2932
2933 rdata->nr_iov = 1;
2934 list_for_each_entry_safe(page, tpage, &rdata->pages, lru) {
2935 if (remaining >= PAGE_CACHE_SIZE) {
2936 /* enough data to fill the page */
2937 rdata->iov[rdata->nr_iov].iov_base = kmap(page);
2938 rdata->iov[rdata->nr_iov].iov_len = PAGE_CACHE_SIZE;
2939 cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu",
2940 rdata->nr_iov, page->index,
2941 rdata->iov[rdata->nr_iov].iov_base,
2942 rdata->iov[rdata->nr_iov].iov_len);
2943 ++rdata->nr_iov;
2944 len += PAGE_CACHE_SIZE;
2945 remaining -= PAGE_CACHE_SIZE;
2946 } else if (remaining > 0) {
2947 /* enough for partial page, fill and zero the rest */
2948 rdata->iov[rdata->nr_iov].iov_base = kmap(page);
2949 rdata->iov[rdata->nr_iov].iov_len = remaining;
2950 cFYI(1, "%u: idx=%lu iov_base=%p iov_len=%zu",
2951 rdata->nr_iov, page->index,
2952 rdata->iov[rdata->nr_iov].iov_base,
2953 rdata->iov[rdata->nr_iov].iov_len);
2954 memset(rdata->iov[rdata->nr_iov].iov_base + remaining,
2955 '\0', PAGE_CACHE_SIZE - remaining);
2956 ++rdata->nr_iov;
2957 len += remaining;
2958 remaining = 0;
2959 } else if (page->index > eof_index) {
2960 /*
2961 * The VFS will not try to do readahead past the
2962 * i_size, but it's possible that we have outstanding
2963 * writes with gaps in the middle and the i_size hasn't
2964 * caught up yet. Populate those with zeroed out pages
2965 * to prevent the VFS from repeatedly attempting to
2966 * fill them until the writes are flushed.
2967 */
2968 zero_user(page, 0, PAGE_CACHE_SIZE);
2969 list_del(&page->lru);
2970 lru_cache_add_file(page);
2971 flush_dcache_page(page);
2972 SetPageUptodate(page);
2973 unlock_page(page);
2974 page_cache_release(page);
2975 } else {
2976 /* no need to hold page hostage */
2977 list_del(&page->lru);
2978 lru_cache_add_file(page);
2979 unlock_page(page);
2980 page_cache_release(page);
2981 }
2982 }
2983
2984 return len;
2985 }
2986
2987 static int cifs_readpages(struct file *file, struct address_space *mapping,
2988 struct list_head *page_list, unsigned num_pages)
2989 {
2990 int rc;
2991 struct list_head tmplist;
2992 struct cifsFileInfo *open_file = file->private_data;
2993 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
2994 unsigned int rsize = cifs_sb->rsize;
2995 pid_t pid;
2996
2997 /*
2998 * Give up immediately if rsize is too small to read an entire page.
2999 * The VFS will fall back to readpage. We should never reach this
3000 * point however since we set ra_pages to 0 when the rsize is smaller
3001 * than a cache page.
3002 */
3003 if (unlikely(rsize < PAGE_CACHE_SIZE))
3004 return 0;
3005
3006 /*
3007 * Reads as many pages as possible from fscache. Returns -ENOBUFS
3008 * immediately if the cookie is negative
3009 */
3010 rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
3011 &num_pages);
3012 if (rc == 0)
3013 return rc;
3014
3015 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3016 pid = open_file->pid;
3017 else
3018 pid = current->tgid;
3019
3020 rc = 0;
3021 INIT_LIST_HEAD(&tmplist);
3022
3023 cFYI(1, "%s: file=%p mapping=%p num_pages=%u", __func__, file,
3024 mapping, num_pages);
3025
3026 /*
3027 * Start with the page at end of list and move it to private
3028 * list. Do the same with any following pages until we hit
3029 * the rsize limit, hit an index discontinuity, or run out of
3030 * pages. Issue the async read and then start the loop again
3031 * until the list is empty.
3032 *
3033 * Note that list order is important. The page_list is in
3034 * the order of declining indexes. When we put the pages in
3035 * the rdata->pages, then we want them in increasing order.
3036 */
3037 while (!list_empty(page_list)) {
3038 unsigned int bytes = PAGE_CACHE_SIZE;
3039 unsigned int expected_index;
3040 unsigned int nr_pages = 1;
3041 loff_t offset;
3042 struct page *page, *tpage;
3043 struct cifs_readdata *rdata;
3044
3045 page = list_entry(page_list->prev, struct page, lru);
3046
3047 /*
3048 * Lock the page and put it in the cache. Since no one else
3049 * should have access to this page, we're safe to simply set
3050 * PG_locked without checking it first.
3051 */
3052 __set_page_locked(page);
3053 rc = add_to_page_cache_locked(page, mapping,
3054 page->index, GFP_KERNEL);
3055
3056 /* give up if we can't stick it in the cache */
3057 if (rc) {
3058 __clear_page_locked(page);
3059 break;
3060 }
3061
3062 /* move first page to the tmplist */
3063 offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
3064 list_move_tail(&page->lru, &tmplist);
3065
3066 /* now try and add more pages onto the request */
3067 expected_index = page->index + 1;
3068 list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {
3069 /* discontinuity ? */
3070 if (page->index != expected_index)
3071 break;
3072
3073 /* would this page push the read over the rsize? */
3074 if (bytes + PAGE_CACHE_SIZE > rsize)
3075 break;
3076
3077 __set_page_locked(page);
3078 if (add_to_page_cache_locked(page, mapping,
3079 page->index, GFP_KERNEL)) {
3080 __clear_page_locked(page);
3081 break;
3082 }
3083 list_move_tail(&page->lru, &tmplist);
3084 bytes += PAGE_CACHE_SIZE;
3085 expected_index++;
3086 nr_pages++;
3087 }
3088
3089 rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
3090 if (!rdata) {
3091 /* best to give up if we're out of mem */
3092 list_for_each_entry_safe(page, tpage, &tmplist, lru) {
3093 list_del(&page->lru);
3094 lru_cache_add_file(page);
3095 unlock_page(page);
3096 page_cache_release(page);
3097 }
3098 rc = -ENOMEM;
3099 break;
3100 }
3101
3102 rdata->cfile = cifsFileInfo_get(open_file);
3103 rdata->mapping = mapping;
3104 rdata->offset = offset;
3105 rdata->bytes = bytes;
3106 rdata->pid = pid;
3107 rdata->marshal_iov = cifs_readpages_marshal_iov;
3108 list_splice_init(&tmplist, &rdata->pages);
3109
3110 rc = cifs_retry_async_readv(rdata);
3111 if (rc != 0) {
3112 list_for_each_entry_safe(page, tpage, &rdata->pages,
3113 lru) {
3114 list_del(&page->lru);
3115 lru_cache_add_file(page);
3116 unlock_page(page);
3117 page_cache_release(page);
3118 }
3119 kref_put(&rdata->refcount, cifs_readdata_release);
3120 break;
3121 }
3122
3123 kref_put(&rdata->refcount, cifs_readdata_release);
3124 }
3125
3126 return rc;
3127 }
3128
3129 static int cifs_readpage_worker(struct file *file, struct page *page,
3130 loff_t *poffset)
3131 {
3132 char *read_data;
3133 int rc;
3134
3135 /* Is the page cached? */
3136 rc = cifs_readpage_from_fscache(file->f_path.dentry->d_inode, page);
3137 if (rc == 0)
3138 goto read_complete;
3139
3140 page_cache_get(page);
3141 read_data = kmap(page);
3142 /* for reads over a certain size could initiate async read ahead */
3143
3144 rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
3145
3146 if (rc < 0)
3147 goto io_error;
3148 else
3149 cFYI(1, "Bytes read %d", rc);
3150
3151 file->f_path.dentry->d_inode->i_atime =
3152 current_fs_time(file->f_path.dentry->d_inode->i_sb);
3153
3154 if (PAGE_CACHE_SIZE > rc)
3155 memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
3156
3157 flush_dcache_page(page);
3158 SetPageUptodate(page);
3159
3160 /* send this page to the cache */
3161 cifs_readpage_to_fscache(file->f_path.dentry->d_inode, page);
3162
3163 rc = 0;
3164
3165 io_error:
3166 kunmap(page);
3167 page_cache_release(page);
3168
3169 read_complete:
3170 return rc;
3171 }
3172
3173 static int cifs_readpage(struct file *file, struct page *page)
3174 {
3175 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
3176 int rc = -EACCES;
3177 unsigned int xid;
3178
3179 xid = get_xid();
3180
3181 if (file->private_data == NULL) {
3182 rc = -EBADF;
3183 free_xid(xid);
3184 return rc;
3185 }
3186
3187 cFYI(1, "readpage %p at offset %d 0x%x",
3188 page, (int)offset, (int)offset);
3189
3190 rc = cifs_readpage_worker(file, page, &offset);
3191
3192 unlock_page(page);
3193
3194 free_xid(xid);
3195 return rc;
3196 }
3197
3198 static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
3199 {
3200 struct cifsFileInfo *open_file;
3201
3202 spin_lock(&cifs_file_list_lock);
3203 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
3204 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
3205 spin_unlock(&cifs_file_list_lock);
3206 return 1;
3207 }
3208 }
3209 spin_unlock(&cifs_file_list_lock);
3210 return 0;
3211 }
3212
3213 /* We do not want to update the file size from server for inodes
3214 open for write - to avoid races with writepage extending
3215 the file - in the future we could consider allowing
3216 refreshing the inode only on increases in the file size
3217 but this is tricky to do without racing with writebehind
3218 page caching in the current Linux kernel design */
3219 bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
3220 {
3221 if (!cifsInode)
3222 return true;
3223
3224 if (is_inode_writable(cifsInode)) {
3225 /* This inode is open for write at least once */
3226 struct cifs_sb_info *cifs_sb;
3227
3228 cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
3229 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
3230 /* since no page cache to corrupt on directio
3231 we can change size safely */
3232 return true;
3233 }
3234
3235 if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
3236 return true;
3237
3238 return false;
3239 } else
3240 return true;
3241 }
3242
3243 static int cifs_write_begin(struct file *file, struct address_space *mapping,
3244 loff_t pos, unsigned len, unsigned flags,
3245 struct page **pagep, void **fsdata)
3246 {
3247 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
3248 loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
3249 loff_t page_start = pos & PAGE_MASK;
3250 loff_t i_size;
3251 struct page *page;
3252 int rc = 0;
3253
3254 cFYI(1, "write_begin from %lld len %d", (long long)pos, len);
3255
3256 page = grab_cache_page_write_begin(mapping, index, flags);
3257 if (!page) {
3258 rc = -ENOMEM;
3259 goto out;
3260 }
3261
3262 if (PageUptodate(page))
3263 goto out;
3264
3265 /*
3266 * If we write a full page it will be up to date, no need to read from
3267 * the server. If the write is short, we'll end up doing a sync write
3268 * instead.
3269 */
3270 if (len == PAGE_CACHE_SIZE)
3271 goto out;
3272
3273 /*
3274 * optimize away the read when we have an oplock, and we're not
3275 * expecting to use any of the data we'd be reading in. That
3276 * is, when the page lies beyond the EOF, or straddles the EOF
3277 * and the write will cover all of the existing data.
3278 */
3279 if (CIFS_I(mapping->host)->clientCanCacheRead) {
3280 i_size = i_size_read(mapping->host);
3281 if (page_start >= i_size ||
3282 (offset == 0 && (pos + len) >= i_size)) {
3283 zero_user_segments(page, 0, offset,
3284 offset + len,
3285 PAGE_CACHE_SIZE);
3286 /*
3287 * PageChecked means that the parts of the page
3288 * to which we're not writing are considered up
3289 * to date. Once the data is copied to the
3290 * page, it can be set uptodate.
3291 */
3292 SetPageChecked(page);
3293 goto out;
3294 }
3295 }
3296
3297 if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
3298 /*
3299 * might as well read a page, it is fast enough. If we get
3300 * an error, we don't need to return it. cifs_write_end will
3301 * do a sync write instead since PG_uptodate isn't set.
3302 */
3303 cifs_readpage_worker(file, page, &page_start);
3304 } else {
3305 /* we could try using another file handle if there is one -
3306 but how would we lock it to prevent close of that handle
3307 racing with this read? In any case
3308 this will be written out by write_end so is fine */
3309 }
3310 out:
3311 *pagep = page;
3312 return rc;
3313 }
3314
3315 static int cifs_release_page(struct page *page, gfp_t gfp)
3316 {
3317 if (PagePrivate(page))
3318 return 0;
3319
3320 return cifs_fscache_release_page(page, gfp);
3321 }
3322
3323 static void cifs_invalidate_page(struct page *page, unsigned long offset)
3324 {
3325 struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
3326
3327 if (offset == 0)
3328 cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
3329 }
3330
3331 static int cifs_launder_page(struct page *page)
3332 {
3333 int rc = 0;
3334 loff_t range_start = page_offset(page);
3335 loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
3336 struct writeback_control wbc = {
3337 .sync_mode = WB_SYNC_ALL,
3338 .nr_to_write = 0,
3339 .range_start = range_start,
3340 .range_end = range_end,
3341 };
3342
3343 cFYI(1, "Launder page: %p", page);
3344
3345 if (clear_page_dirty_for_io(page))
3346 rc = cifs_writepage_locked(page, &wbc);
3347
3348 cifs_fscache_invalidate_page(page, page->mapping->host);
3349 return rc;
3350 }
3351
3352 void cifs_oplock_break(struct work_struct *work)
3353 {
3354 struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
3355 oplock_break);
3356 struct inode *inode = cfile->dentry->d_inode;
3357 struct cifsInodeInfo *cinode = CIFS_I(inode);
3358 int rc = 0;
3359
3360 if (inode && S_ISREG(inode->i_mode)) {
3361 if (cinode->clientCanCacheRead)
3362 break_lease(inode, O_RDONLY);
3363 else
3364 break_lease(inode, O_WRONLY);
3365 rc = filemap_fdatawrite(inode->i_mapping);
3366 if (cinode->clientCanCacheRead == 0) {
3367 rc = filemap_fdatawait(inode->i_mapping);
3368 mapping_set_error(inode->i_mapping, rc);
3369 invalidate_remote_inode(inode);
3370 }
3371 cFYI(1, "Oplock flush inode %p rc %d", inode, rc);
3372 }
3373
3374 rc = cifs_push_locks(cfile);
3375 if (rc)
3376 cERROR(1, "Push locks rc = %d", rc);
3377
3378 /*
3379 * releasing stale oplock after recent reconnect of smb session using
3380 * a now incorrect file handle is not a data integrity issue but do
3381 * not bother sending an oplock release if session to server still is
3382 * disconnected since oplock already released by the server
3383 */
3384 if (!cfile->oplock_break_cancelled) {
3385 rc = CIFSSMBLock(0, tlink_tcon(cfile->tlink), cfile->fid.netfid,
3386 current->tgid, 0, 0, 0, 0,
3387 LOCKING_ANDX_OPLOCK_RELEASE, false,
3388 cinode->clientCanCacheRead ? 1 : 0);
3389 cFYI(1, "Oplock release rc = %d", rc);
3390 }
3391 }
3392
3393 const struct address_space_operations cifs_addr_ops = {
3394 .readpage = cifs_readpage,
3395 .readpages = cifs_readpages,
3396 .writepage = cifs_writepage,
3397 .writepages = cifs_writepages,
3398 .write_begin = cifs_write_begin,
3399 .write_end = cifs_write_end,
3400 .set_page_dirty = __set_page_dirty_nobuffers,
3401 .releasepage = cifs_release_page,
3402 .invalidatepage = cifs_invalidate_page,
3403 .launder_page = cifs_launder_page,
3404 };
3405
3406 /*
3407 * cifs_readpages requires the server to support a buffer large enough to
3408 * contain the header plus one complete page of data. Otherwise, we need
3409 * to leave cifs_readpages out of the address space operations.
3410 */
3411 const struct address_space_operations cifs_addr_ops_smallbuf = {
3412 .readpage = cifs_readpage,
3413 .writepage = cifs_writepage,
3414 .writepages = cifs_writepages,
3415 .write_begin = cifs_write_begin,
3416 .write_end = cifs_write_end,
3417 .set_page_dirty = __set_page_dirty_nobuffers,
3418 .releasepage = cifs_release_page,
3419 .invalidatepage = cifs_invalidate_page,
3420 .launder_page = cifs_launder_page,
3421 };
kernel source for telekom puls (alcatel/mediatek)