/fs/cifs/file.c
C | 2462 lines | 1820 code | 346 blank | 296 comment | 447 complexity | 2972a9f8ae8a89471fb16a749c5df6ed MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
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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 <asm/div64.h>
36#include "cifsfs.h"
37#include "cifspdu.h"
38#include "cifsglob.h"
39#include "cifsproto.h"
40#include "cifs_unicode.h"
41#include "cifs_debug.h"
42#include "cifs_fs_sb.h"
43#include "fscache.h"
44
45static inline int cifs_convert_flags(unsigned int flags)
46{
47 if ((flags & O_ACCMODE) == O_RDONLY)
48 return GENERIC_READ;
49 else if ((flags & O_ACCMODE) == O_WRONLY)
50 return GENERIC_WRITE;
51 else if ((flags & O_ACCMODE) == O_RDWR) {
52 /* GENERIC_ALL is too much permission to request
53 can cause unnecessary access denied on create */
54 /* return GENERIC_ALL; */
55 return (GENERIC_READ | GENERIC_WRITE);
56 }
57
58 return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
59 FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
60 FILE_READ_DATA);
61}
62
63static u32 cifs_posix_convert_flags(unsigned int flags)
64{
65 u32 posix_flags = 0;
66
67 if ((flags & O_ACCMODE) == O_RDONLY)
68 posix_flags = SMB_O_RDONLY;
69 else if ((flags & O_ACCMODE) == O_WRONLY)
70 posix_flags = SMB_O_WRONLY;
71 else if ((flags & O_ACCMODE) == O_RDWR)
72 posix_flags = SMB_O_RDWR;
73
74 if (flags & O_CREAT)
75 posix_flags |= SMB_O_CREAT;
76 if (flags & O_EXCL)
77 posix_flags |= SMB_O_EXCL;
78 if (flags & O_TRUNC)
79 posix_flags |= SMB_O_TRUNC;
80 /* be safe and imply O_SYNC for O_DSYNC */
81 if (flags & O_DSYNC)
82 posix_flags |= SMB_O_SYNC;
83 if (flags & O_DIRECTORY)
84 posix_flags |= SMB_O_DIRECTORY;
85 if (flags & O_NOFOLLOW)
86 posix_flags |= SMB_O_NOFOLLOW;
87 if (flags & O_DIRECT)
88 posix_flags |= SMB_O_DIRECT;
89
90 return posix_flags;
91}
92
93static inline int cifs_get_disposition(unsigned int flags)
94{
95 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
96 return FILE_CREATE;
97 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
98 return FILE_OVERWRITE_IF;
99 else if ((flags & O_CREAT) == O_CREAT)
100 return FILE_OPEN_IF;
101 else if ((flags & O_TRUNC) == O_TRUNC)
102 return FILE_OVERWRITE;
103 else
104 return FILE_OPEN;
105}
106
107int cifs_posix_open(char *full_path, struct inode **pinode,
108 struct super_block *sb, int mode, unsigned int f_flags,
109 __u32 *poplock, __u16 *pnetfid, int xid)
110{
111 int rc;
112 FILE_UNIX_BASIC_INFO *presp_data;
113 __u32 posix_flags = 0;
114 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
115 struct cifs_fattr fattr;
116 struct tcon_link *tlink;
117 struct cifs_tcon *tcon;
118
119 cFYI(1, "posix open %s", full_path);
120
121 presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
122 if (presp_data == NULL)
123 return -ENOMEM;
124
125 tlink = cifs_sb_tlink(cifs_sb);
126 if (IS_ERR(tlink)) {
127 rc = PTR_ERR(tlink);
128 goto posix_open_ret;
129 }
130
131 tcon = tlink_tcon(tlink);
132 mode &= ~current_umask();
133
134 posix_flags = cifs_posix_convert_flags(f_flags);
135 rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
136 poplock, full_path, cifs_sb->local_nls,
137 cifs_sb->mnt_cifs_flags &
138 CIFS_MOUNT_MAP_SPECIAL_CHR);
139 cifs_put_tlink(tlink);
140
141 if (rc)
142 goto posix_open_ret;
143
144 if (presp_data->Type == cpu_to_le32(-1))
145 goto posix_open_ret; /* open ok, caller does qpathinfo */
146
147 if (!pinode)
148 goto posix_open_ret; /* caller does not need info */
149
150 cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
151
152 /* get new inode and set it up */
153 if (*pinode == NULL) {
154 cifs_fill_uniqueid(sb, &fattr);
155 *pinode = cifs_iget(sb, &fattr);
156 if (!*pinode) {
157 rc = -ENOMEM;
158 goto posix_open_ret;
159 }
160 } else {
161 cifs_fattr_to_inode(*pinode, &fattr);
162 }
163
164posix_open_ret:
165 kfree(presp_data);
166 return rc;
167}
168
169static int
170cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
171 struct cifs_tcon *tcon, unsigned int f_flags, __u32 *poplock,
172 __u16 *pnetfid, int xid)
173{
174 int rc;
175 int desiredAccess;
176 int disposition;
177 FILE_ALL_INFO *buf;
178
179 desiredAccess = cifs_convert_flags(f_flags);
180
181/*********************************************************************
182 * open flag mapping table:
183 *
184 * POSIX Flag CIFS Disposition
185 * ---------- ----------------
186 * O_CREAT FILE_OPEN_IF
187 * O_CREAT | O_EXCL FILE_CREATE
188 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
189 * O_TRUNC FILE_OVERWRITE
190 * none of the above FILE_OPEN
191 *
192 * Note that there is not a direct match between disposition
193 * FILE_SUPERSEDE (ie create whether or not file exists although
194 * O_CREAT | O_TRUNC is similar but truncates the existing
195 * file rather than creating a new file as FILE_SUPERSEDE does
196 * (which uses the attributes / metadata passed in on open call)
197 *?
198 *? O_SYNC is a reasonable match to CIFS writethrough flag
199 *? and the read write flags match reasonably. O_LARGEFILE
200 *? is irrelevant because largefile support is always used
201 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
202 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
203 *********************************************************************/
204
205 disposition = cifs_get_disposition(f_flags);
206
207 /* BB pass O_SYNC flag through on file attributes .. BB */
208
209 buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
210 if (!buf)
211 return -ENOMEM;
212
213 if (tcon->ses->capabilities & CAP_NT_SMBS)
214 rc = CIFSSMBOpen(xid, tcon, full_path, disposition,
215 desiredAccess, CREATE_NOT_DIR, pnetfid, poplock, buf,
216 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
217 & CIFS_MOUNT_MAP_SPECIAL_CHR);
218 else
219 rc = SMBLegacyOpen(xid, tcon, full_path, disposition,
220 desiredAccess, CREATE_NOT_DIR, pnetfid, poplock, buf,
221 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
222 & CIFS_MOUNT_MAP_SPECIAL_CHR);
223
224 if (rc)
225 goto out;
226
227 if (tcon->unix_ext)
228 rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
229 xid);
230 else
231 rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
232 xid, pnetfid);
233
234out:
235 kfree(buf);
236 return rc;
237}
238
239struct cifsFileInfo *
240cifs_new_fileinfo(__u16 fileHandle, struct file *file,
241 struct tcon_link *tlink, __u32 oplock)
242{
243 struct dentry *dentry = file->f_path.dentry;
244 struct inode *inode = dentry->d_inode;
245 struct cifsInodeInfo *pCifsInode = CIFS_I(inode);
246 struct cifsFileInfo *pCifsFile;
247
248 pCifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
249 if (pCifsFile == NULL)
250 return pCifsFile;
251
252 pCifsFile->count = 1;
253 pCifsFile->netfid = fileHandle;
254 pCifsFile->pid = current->tgid;
255 pCifsFile->uid = current_fsuid();
256 pCifsFile->dentry = dget(dentry);
257 pCifsFile->f_flags = file->f_flags;
258 pCifsFile->invalidHandle = false;
259 pCifsFile->tlink = cifs_get_tlink(tlink);
260 mutex_init(&pCifsFile->fh_mutex);
261 mutex_init(&pCifsFile->lock_mutex);
262 INIT_LIST_HEAD(&pCifsFile->llist);
263 INIT_WORK(&pCifsFile->oplock_break, cifs_oplock_break);
264
265 spin_lock(&cifs_file_list_lock);
266 list_add(&pCifsFile->tlist, &(tlink_tcon(tlink)->openFileList));
267 /* if readable file instance put first in list*/
268 if (file->f_mode & FMODE_READ)
269 list_add(&pCifsFile->flist, &pCifsInode->openFileList);
270 else
271 list_add_tail(&pCifsFile->flist, &pCifsInode->openFileList);
272 spin_unlock(&cifs_file_list_lock);
273
274 cifs_set_oplock_level(pCifsInode, oplock);
275
276 file->private_data = pCifsFile;
277 return pCifsFile;
278}
279
280/*
281 * Release a reference on the file private data. This may involve closing
282 * the filehandle out on the server. Must be called without holding
283 * cifs_file_list_lock.
284 */
285void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
286{
287 struct inode *inode = cifs_file->dentry->d_inode;
288 struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink);
289 struct cifsInodeInfo *cifsi = CIFS_I(inode);
290 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
291 struct cifsLockInfo *li, *tmp;
292
293 spin_lock(&cifs_file_list_lock);
294 if (--cifs_file->count > 0) {
295 spin_unlock(&cifs_file_list_lock);
296 return;
297 }
298
299 /* remove it from the lists */
300 list_del(&cifs_file->flist);
301 list_del(&cifs_file->tlist);
302
303 if (list_empty(&cifsi->openFileList)) {
304 cFYI(1, "closing last open instance for inode %p",
305 cifs_file->dentry->d_inode);
306
307 /* in strict cache mode we need invalidate mapping on the last
308 close because it may cause a error when we open this file
309 again and get at least level II oplock */
310 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
311 CIFS_I(inode)->invalid_mapping = true;
312
313 cifs_set_oplock_level(cifsi, 0);
314 }
315 spin_unlock(&cifs_file_list_lock);
316
317 if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
318 int xid, rc;
319
320 xid = GetXid();
321 rc = CIFSSMBClose(xid, tcon, cifs_file->netfid);
322 FreeXid(xid);
323 }
324
325 /* Delete any outstanding lock records. We'll lose them when the file
326 * is closed anyway.
327 */
328 mutex_lock(&cifs_file->lock_mutex);
329 list_for_each_entry_safe(li, tmp, &cifs_file->llist, llist) {
330 list_del(&li->llist);
331 kfree(li);
332 }
333 mutex_unlock(&cifs_file->lock_mutex);
334
335 cifs_put_tlink(cifs_file->tlink);
336 dput(cifs_file->dentry);
337 kfree(cifs_file);
338}
339
340int cifs_open(struct inode *inode, struct file *file)
341{
342 int rc = -EACCES;
343 int xid;
344 __u32 oplock;
345 struct cifs_sb_info *cifs_sb;
346 struct cifs_tcon *tcon;
347 struct tcon_link *tlink;
348 struct cifsFileInfo *pCifsFile = NULL;
349 char *full_path = NULL;
350 bool posix_open_ok = false;
351 __u16 netfid;
352
353 xid = GetXid();
354
355 cifs_sb = CIFS_SB(inode->i_sb);
356 tlink = cifs_sb_tlink(cifs_sb);
357 if (IS_ERR(tlink)) {
358 FreeXid(xid);
359 return PTR_ERR(tlink);
360 }
361 tcon = tlink_tcon(tlink);
362
363 full_path = build_path_from_dentry(file->f_path.dentry);
364 if (full_path == NULL) {
365 rc = -ENOMEM;
366 goto out;
367 }
368
369 cFYI(1, "inode = 0x%p file flags are 0x%x for %s",
370 inode, file->f_flags, full_path);
371
372 if (oplockEnabled)
373 oplock = REQ_OPLOCK;
374 else
375 oplock = 0;
376
377 if (!tcon->broken_posix_open && tcon->unix_ext &&
378 (tcon->ses->capabilities & CAP_UNIX) &&
379 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
380 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
381 /* can not refresh inode info since size could be stale */
382 rc = cifs_posix_open(full_path, &inode, inode->i_sb,
383 cifs_sb->mnt_file_mode /* ignored */,
384 file->f_flags, &oplock, &netfid, xid);
385 if (rc == 0) {
386 cFYI(1, "posix open succeeded");
387 posix_open_ok = true;
388 } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
389 if (tcon->ses->serverNOS)
390 cERROR(1, "server %s of type %s returned"
391 " unexpected error on SMB posix open"
392 ", disabling posix open support."
393 " Check if server update available.",
394 tcon->ses->serverName,
395 tcon->ses->serverNOS);
396 tcon->broken_posix_open = true;
397 } else if ((rc != -EIO) && (rc != -EREMOTE) &&
398 (rc != -EOPNOTSUPP)) /* path not found or net err */
399 goto out;
400 /* else fallthrough to retry open the old way on network i/o
401 or DFS errors */
402 }
403
404 if (!posix_open_ok) {
405 rc = cifs_nt_open(full_path, inode, cifs_sb, tcon,
406 file->f_flags, &oplock, &netfid, xid);
407 if (rc)
408 goto out;
409 }
410
411 pCifsFile = cifs_new_fileinfo(netfid, file, tlink, oplock);
412 if (pCifsFile == NULL) {
413 CIFSSMBClose(xid, tcon, netfid);
414 rc = -ENOMEM;
415 goto out;
416 }
417
418 cifs_fscache_set_inode_cookie(inode, file);
419
420 if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
421 /* time to set mode which we can not set earlier due to
422 problems creating new read-only files */
423 struct cifs_unix_set_info_args args = {
424 .mode = inode->i_mode,
425 .uid = NO_CHANGE_64,
426 .gid = NO_CHANGE_64,
427 .ctime = NO_CHANGE_64,
428 .atime = NO_CHANGE_64,
429 .mtime = NO_CHANGE_64,
430 .device = 0,
431 };
432 CIFSSMBUnixSetFileInfo(xid, tcon, &args, netfid,
433 pCifsFile->pid);
434 }
435
436out:
437 kfree(full_path);
438 FreeXid(xid);
439 cifs_put_tlink(tlink);
440 return rc;
441}
442
443/* Try to reacquire byte range locks that were released when session */
444/* to server was lost */
445static int cifs_relock_file(struct cifsFileInfo *cifsFile)
446{
447 int rc = 0;
448
449/* BB list all locks open on this file and relock */
450
451 return rc;
452}
453
454static int cifs_reopen_file(struct cifsFileInfo *pCifsFile, bool can_flush)
455{
456 int rc = -EACCES;
457 int xid;
458 __u32 oplock;
459 struct cifs_sb_info *cifs_sb;
460 struct cifs_tcon *tcon;
461 struct cifsInodeInfo *pCifsInode;
462 struct inode *inode;
463 char *full_path = NULL;
464 int desiredAccess;
465 int disposition = FILE_OPEN;
466 __u16 netfid;
467
468 xid = GetXid();
469 mutex_lock(&pCifsFile->fh_mutex);
470 if (!pCifsFile->invalidHandle) {
471 mutex_unlock(&pCifsFile->fh_mutex);
472 rc = 0;
473 FreeXid(xid);
474 return rc;
475 }
476
477 inode = pCifsFile->dentry->d_inode;
478 cifs_sb = CIFS_SB(inode->i_sb);
479 tcon = tlink_tcon(pCifsFile->tlink);
480
481/* can not grab rename sem here because various ops, including
482 those that already have the rename sem can end up causing writepage
483 to get called and if the server was down that means we end up here,
484 and we can never tell if the caller already has the rename_sem */
485 full_path = build_path_from_dentry(pCifsFile->dentry);
486 if (full_path == NULL) {
487 rc = -ENOMEM;
488 mutex_unlock(&pCifsFile->fh_mutex);
489 FreeXid(xid);
490 return rc;
491 }
492
493 cFYI(1, "inode = 0x%p file flags 0x%x for %s",
494 inode, pCifsFile->f_flags, full_path);
495
496 if (oplockEnabled)
497 oplock = REQ_OPLOCK;
498 else
499 oplock = 0;
500
501 if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
502 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
503 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
504
505 /*
506 * O_CREAT, O_EXCL and O_TRUNC already had their effect on the
507 * original open. Must mask them off for a reopen.
508 */
509 unsigned int oflags = pCifsFile->f_flags &
510 ~(O_CREAT | O_EXCL | O_TRUNC);
511
512 rc = cifs_posix_open(full_path, NULL, inode->i_sb,
513 cifs_sb->mnt_file_mode /* ignored */,
514 oflags, &oplock, &netfid, xid);
515 if (rc == 0) {
516 cFYI(1, "posix reopen succeeded");
517 goto reopen_success;
518 }
519 /* fallthrough to retry open the old way on errors, especially
520 in the reconnect path it is important to retry hard */
521 }
522
523 desiredAccess = cifs_convert_flags(pCifsFile->f_flags);
524
525 /* Can not refresh inode by passing in file_info buf to be returned
526 by SMBOpen and then calling get_inode_info with returned buf
527 since file might have write behind data that needs to be flushed
528 and server version of file size can be stale. If we knew for sure
529 that inode was not dirty locally we could do this */
530
531 rc = CIFSSMBOpen(xid, tcon, full_path, disposition, desiredAccess,
532 CREATE_NOT_DIR, &netfid, &oplock, NULL,
533 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
534 CIFS_MOUNT_MAP_SPECIAL_CHR);
535 if (rc) {
536 mutex_unlock(&pCifsFile->fh_mutex);
537 cFYI(1, "cifs_open returned 0x%x", rc);
538 cFYI(1, "oplock: %d", oplock);
539 goto reopen_error_exit;
540 }
541
542reopen_success:
543 pCifsFile->netfid = netfid;
544 pCifsFile->invalidHandle = false;
545 mutex_unlock(&pCifsFile->fh_mutex);
546 pCifsInode = CIFS_I(inode);
547
548 if (can_flush) {
549 rc = filemap_write_and_wait(inode->i_mapping);
550 mapping_set_error(inode->i_mapping, rc);
551
552 if (tcon->unix_ext)
553 rc = cifs_get_inode_info_unix(&inode,
554 full_path, inode->i_sb, xid);
555 else
556 rc = cifs_get_inode_info(&inode,
557 full_path, NULL, inode->i_sb,
558 xid, NULL);
559 } /* else we are writing out data to server already
560 and could deadlock if we tried to flush data, and
561 since we do not know if we have data that would
562 invalidate the current end of file on the server
563 we can not go to the server to get the new inod
564 info */
565
566 cifs_set_oplock_level(pCifsInode, oplock);
567
568 cifs_relock_file(pCifsFile);
569
570reopen_error_exit:
571 kfree(full_path);
572 FreeXid(xid);
573 return rc;
574}
575
576int cifs_close(struct inode *inode, struct file *file)
577{
578 if (file->private_data != NULL) {
579 cifsFileInfo_put(file->private_data);
580 file->private_data = NULL;
581 }
582
583 /* return code from the ->release op is always ignored */
584 return 0;
585}
586
587int cifs_closedir(struct inode *inode, struct file *file)
588{
589 int rc = 0;
590 int xid;
591 struct cifsFileInfo *pCFileStruct = file->private_data;
592 char *ptmp;
593
594 cFYI(1, "Closedir inode = 0x%p", inode);
595
596 xid = GetXid();
597
598 if (pCFileStruct) {
599 struct cifs_tcon *pTcon = tlink_tcon(pCFileStruct->tlink);
600
601 cFYI(1, "Freeing private data in close dir");
602 spin_lock(&cifs_file_list_lock);
603 if (!pCFileStruct->srch_inf.endOfSearch &&
604 !pCFileStruct->invalidHandle) {
605 pCFileStruct->invalidHandle = true;
606 spin_unlock(&cifs_file_list_lock);
607 rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
608 cFYI(1, "Closing uncompleted readdir with rc %d",
609 rc);
610 /* not much we can do if it fails anyway, ignore rc */
611 rc = 0;
612 } else
613 spin_unlock(&cifs_file_list_lock);
614 ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
615 if (ptmp) {
616 cFYI(1, "closedir free smb buf in srch struct");
617 pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
618 if (pCFileStruct->srch_inf.smallBuf)
619 cifs_small_buf_release(ptmp);
620 else
621 cifs_buf_release(ptmp);
622 }
623 cifs_put_tlink(pCFileStruct->tlink);
624 kfree(file->private_data);
625 file->private_data = NULL;
626 }
627 /* BB can we lock the filestruct while this is going on? */
628 FreeXid(xid);
629 return rc;
630}
631
632static int store_file_lock(struct cifsFileInfo *fid, __u64 len,
633 __u64 offset, __u8 lockType)
634{
635 struct cifsLockInfo *li =
636 kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
637 if (li == NULL)
638 return -ENOMEM;
639 li->offset = offset;
640 li->length = len;
641 li->type = lockType;
642 mutex_lock(&fid->lock_mutex);
643 list_add(&li->llist, &fid->llist);
644 mutex_unlock(&fid->lock_mutex);
645 return 0;
646}
647
648int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
649{
650 int rc, xid;
651 __u32 numLock = 0;
652 __u32 numUnlock = 0;
653 __u64 length;
654 bool wait_flag = false;
655 struct cifs_sb_info *cifs_sb;
656 struct cifs_tcon *tcon;
657 __u16 netfid;
658 __u8 lockType = LOCKING_ANDX_LARGE_FILES;
659 bool posix_locking = 0;
660
661 length = 1 + pfLock->fl_end - pfLock->fl_start;
662 rc = -EACCES;
663 xid = GetXid();
664
665 cFYI(1, "Lock parm: 0x%x flockflags: "
666 "0x%x flocktype: 0x%x start: %lld end: %lld",
667 cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
668 pfLock->fl_end);
669
670 if (pfLock->fl_flags & FL_POSIX)
671 cFYI(1, "Posix");
672 if (pfLock->fl_flags & FL_FLOCK)
673 cFYI(1, "Flock");
674 if (pfLock->fl_flags & FL_SLEEP) {
675 cFYI(1, "Blocking lock");
676 wait_flag = true;
677 }
678 if (pfLock->fl_flags & FL_ACCESS)
679 cFYI(1, "Process suspended by mandatory locking - "
680 "not implemented yet");
681 if (pfLock->fl_flags & FL_LEASE)
682 cFYI(1, "Lease on file - not implemented yet");
683 if (pfLock->fl_flags &
684 (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
685 cFYI(1, "Unknown lock flags 0x%x", pfLock->fl_flags);
686
687 if (pfLock->fl_type == F_WRLCK) {
688 cFYI(1, "F_WRLCK ");
689 numLock = 1;
690 } else if (pfLock->fl_type == F_UNLCK) {
691 cFYI(1, "F_UNLCK");
692 numUnlock = 1;
693 /* Check if unlock includes more than
694 one lock range */
695 } else if (pfLock->fl_type == F_RDLCK) {
696 cFYI(1, "F_RDLCK");
697 lockType |= LOCKING_ANDX_SHARED_LOCK;
698 numLock = 1;
699 } else if (pfLock->fl_type == F_EXLCK) {
700 cFYI(1, "F_EXLCK");
701 numLock = 1;
702 } else if (pfLock->fl_type == F_SHLCK) {
703 cFYI(1, "F_SHLCK");
704 lockType |= LOCKING_ANDX_SHARED_LOCK;
705 numLock = 1;
706 } else
707 cFYI(1, "Unknown type of lock");
708
709 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
710 tcon = tlink_tcon(((struct cifsFileInfo *)file->private_data)->tlink);
711 netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
712
713 if ((tcon->ses->capabilities & CAP_UNIX) &&
714 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
715 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
716 posix_locking = 1;
717 /* BB add code here to normalize offset and length to
718 account for negative length which we can not accept over the
719 wire */
720 if (IS_GETLK(cmd)) {
721 if (posix_locking) {
722 int posix_lock_type;
723 if (lockType & LOCKING_ANDX_SHARED_LOCK)
724 posix_lock_type = CIFS_RDLCK;
725 else
726 posix_lock_type = CIFS_WRLCK;
727 rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,
728 length, pfLock, posix_lock_type,
729 wait_flag);
730 FreeXid(xid);
731 return rc;
732 }
733
734 /* BB we could chain these into one lock request BB */
735 rc = CIFSSMBLock(xid, tcon, netfid, length, pfLock->fl_start,
736 0, 1, lockType, 0 /* wait flag */, 0);
737 if (rc == 0) {
738 rc = CIFSSMBLock(xid, tcon, netfid, length,
739 pfLock->fl_start, 1 /* numUnlock */ ,
740 0 /* numLock */ , lockType,
741 0 /* wait flag */, 0);
742 pfLock->fl_type = F_UNLCK;
743 if (rc != 0)
744 cERROR(1, "Error unlocking previously locked "
745 "range %d during test of lock", rc);
746 rc = 0;
747
748 } else {
749 /* if rc == ERR_SHARING_VIOLATION ? */
750 rc = 0;
751
752 if (lockType & LOCKING_ANDX_SHARED_LOCK) {
753 pfLock->fl_type = F_WRLCK;
754 } else {
755 rc = CIFSSMBLock(xid, tcon, netfid, length,
756 pfLock->fl_start, 0, 1,
757 lockType | LOCKING_ANDX_SHARED_LOCK,
758 0 /* wait flag */, 0);
759 if (rc == 0) {
760 rc = CIFSSMBLock(xid, tcon, netfid,
761 length, pfLock->fl_start, 1, 0,
762 lockType |
763 LOCKING_ANDX_SHARED_LOCK,
764 0 /* wait flag */, 0);
765 pfLock->fl_type = F_RDLCK;
766 if (rc != 0)
767 cERROR(1, "Error unlocking "
768 "previously locked range %d "
769 "during test of lock", rc);
770 rc = 0;
771 } else {
772 pfLock->fl_type = F_WRLCK;
773 rc = 0;
774 }
775 }
776 }
777
778 FreeXid(xid);
779 return rc;
780 }
781
782 if (!numLock && !numUnlock) {
783 /* if no lock or unlock then nothing
784 to do since we do not know what it is */
785 FreeXid(xid);
786 return -EOPNOTSUPP;
787 }
788
789 if (posix_locking) {
790 int posix_lock_type;
791 if (lockType & LOCKING_ANDX_SHARED_LOCK)
792 posix_lock_type = CIFS_RDLCK;
793 else
794 posix_lock_type = CIFS_WRLCK;
795
796 if (numUnlock == 1)
797 posix_lock_type = CIFS_UNLCK;
798
799 rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */,
800 length, pfLock, posix_lock_type,
801 wait_flag);
802 } else {
803 struct cifsFileInfo *fid = file->private_data;
804
805 if (numLock) {
806 rc = CIFSSMBLock(xid, tcon, netfid, length,
807 pfLock->fl_start, 0, numLock, lockType,
808 wait_flag, 0);
809
810 if (rc == 0) {
811 /* For Windows locks we must store them. */
812 rc = store_file_lock(fid, length,
813 pfLock->fl_start, lockType);
814 }
815 } else if (numUnlock) {
816 /* For each stored lock that this unlock overlaps
817 completely, unlock it. */
818 int stored_rc = 0;
819 struct cifsLockInfo *li, *tmp;
820
821 rc = 0;
822 mutex_lock(&fid->lock_mutex);
823 list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
824 if (pfLock->fl_start <= li->offset &&
825 (pfLock->fl_start + length) >=
826 (li->offset + li->length)) {
827 stored_rc = CIFSSMBLock(xid, tcon,
828 netfid, li->length,
829 li->offset, 1, 0,
830 li->type, false, 0);
831 if (stored_rc)
832 rc = stored_rc;
833 else {
834 list_del(&li->llist);
835 kfree(li);
836 }
837 }
838 }
839 mutex_unlock(&fid->lock_mutex);
840 }
841 }
842
843 if (pfLock->fl_flags & FL_POSIX)
844 posix_lock_file_wait(file, pfLock);
845 FreeXid(xid);
846 return rc;
847}
848
849/* update the file size (if needed) after a write */
850void
851cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
852 unsigned int bytes_written)
853{
854 loff_t end_of_write = offset + bytes_written;
855
856 if (end_of_write > cifsi->server_eof)
857 cifsi->server_eof = end_of_write;
858}
859
860static ssize_t cifs_write(struct cifsFileInfo *open_file, __u32 pid,
861 const char *write_data, size_t write_size,
862 loff_t *poffset)
863{
864 int rc = 0;
865 unsigned int bytes_written = 0;
866 unsigned int total_written;
867 struct cifs_sb_info *cifs_sb;
868 struct cifs_tcon *pTcon;
869 int xid;
870 struct dentry *dentry = open_file->dentry;
871 struct cifsInodeInfo *cifsi = CIFS_I(dentry->d_inode);
872 struct cifs_io_parms io_parms;
873
874 cifs_sb = CIFS_SB(dentry->d_sb);
875
876 cFYI(1, "write %zd bytes to offset %lld of %s", write_size,
877 *poffset, dentry->d_name.name);
878
879 pTcon = tlink_tcon(open_file->tlink);
880
881 xid = GetXid();
882
883 for (total_written = 0; write_size > total_written;
884 total_written += bytes_written) {
885 rc = -EAGAIN;
886 while (rc == -EAGAIN) {
887 struct kvec iov[2];
888 unsigned int len;
889
890 if (open_file->invalidHandle) {
891 /* we could deadlock if we called
892 filemap_fdatawait from here so tell
893 reopen_file not to flush data to
894 server now */
895 rc = cifs_reopen_file(open_file, false);
896 if (rc != 0)
897 break;
898 }
899
900 len = min((size_t)cifs_sb->wsize,
901 write_size - total_written);
902 /* iov[0] is reserved for smb header */
903 iov[1].iov_base = (char *)write_data + total_written;
904 iov[1].iov_len = len;
905 io_parms.netfid = open_file->netfid;
906 io_parms.pid = pid;
907 io_parms.tcon = pTcon;
908 io_parms.offset = *poffset;
909 io_parms.length = len;
910 rc = CIFSSMBWrite2(xid, &io_parms, &bytes_written, iov,
911 1, 0);
912 }
913 if (rc || (bytes_written == 0)) {
914 if (total_written)
915 break;
916 else {
917 FreeXid(xid);
918 return rc;
919 }
920 } else {
921 cifs_update_eof(cifsi, *poffset, bytes_written);
922 *poffset += bytes_written;
923 }
924 }
925
926 cifs_stats_bytes_written(pTcon, total_written);
927
928 if (total_written > 0) {
929 spin_lock(&dentry->d_inode->i_lock);
930 if (*poffset > dentry->d_inode->i_size)
931 i_size_write(dentry->d_inode, *poffset);
932 spin_unlock(&dentry->d_inode->i_lock);
933 }
934 mark_inode_dirty_sync(dentry->d_inode);
935 FreeXid(xid);
936 return total_written;
937}
938
939struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
940 bool fsuid_only)
941{
942 struct cifsFileInfo *open_file = NULL;
943 struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
944
945 /* only filter by fsuid on multiuser mounts */
946 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
947 fsuid_only = false;
948
949 spin_lock(&cifs_file_list_lock);
950 /* we could simply get the first_list_entry since write-only entries
951 are always at the end of the list but since the first entry might
952 have a close pending, we go through the whole list */
953 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
954 if (fsuid_only && open_file->uid != current_fsuid())
955 continue;
956 if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
957 if (!open_file->invalidHandle) {
958 /* found a good file */
959 /* lock it so it will not be closed on us */
960 cifsFileInfo_get(open_file);
961 spin_unlock(&cifs_file_list_lock);
962 return open_file;
963 } /* else might as well continue, and look for
964 another, or simply have the caller reopen it
965 again rather than trying to fix this handle */
966 } else /* write only file */
967 break; /* write only files are last so must be done */
968 }
969 spin_unlock(&cifs_file_list_lock);
970 return NULL;
971}
972
973struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
974 bool fsuid_only)
975{
976 struct cifsFileInfo *open_file;
977 struct cifs_sb_info *cifs_sb;
978 bool any_available = false;
979 int rc;
980
981 /* Having a null inode here (because mapping->host was set to zero by
982 the VFS or MM) should not happen but we had reports of on oops (due to
983 it being zero) during stress testcases so we need to check for it */
984
985 if (cifs_inode == NULL) {
986 cERROR(1, "Null inode passed to cifs_writeable_file");
987 dump_stack();
988 return NULL;
989 }
990
991 cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
992
993 /* only filter by fsuid on multiuser mounts */
994 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
995 fsuid_only = false;
996
997 spin_lock(&cifs_file_list_lock);
998refind_writable:
999 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1000 if (!any_available && open_file->pid != current->tgid)
1001 continue;
1002 if (fsuid_only && open_file->uid != current_fsuid())
1003 continue;
1004 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
1005 cifsFileInfo_get(open_file);
1006
1007 if (!open_file->invalidHandle) {
1008 /* found a good writable file */
1009 spin_unlock(&cifs_file_list_lock);
1010 return open_file;
1011 }
1012
1013 spin_unlock(&cifs_file_list_lock);
1014
1015 /* Had to unlock since following call can block */
1016 rc = cifs_reopen_file(open_file, false);
1017 if (!rc)
1018 return open_file;
1019
1020 /* if it fails, try another handle if possible */
1021 cFYI(1, "wp failed on reopen file");
1022 cifsFileInfo_put(open_file);
1023
1024 spin_lock(&cifs_file_list_lock);
1025
1026 /* else we simply continue to the next entry. Thus
1027 we do not loop on reopen errors. If we
1028 can not reopen the file, for example if we
1029 reconnected to a server with another client
1030 racing to delete or lock the file we would not
1031 make progress if we restarted before the beginning
1032 of the loop here. */
1033 }
1034 }
1035 /* couldn't find useable FH with same pid, try any available */
1036 if (!any_available) {
1037 any_available = true;
1038 goto refind_writable;
1039 }
1040 spin_unlock(&cifs_file_list_lock);
1041 return NULL;
1042}
1043
1044static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
1045{
1046 struct address_space *mapping = page->mapping;
1047 loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
1048 char *write_data;
1049 int rc = -EFAULT;
1050 int bytes_written = 0;
1051 struct inode *inode;
1052 struct cifsFileInfo *open_file;
1053
1054 if (!mapping || !mapping->host)
1055 return -EFAULT;
1056
1057 inode = page->mapping->host;
1058
1059 offset += (loff_t)from;
1060 write_data = kmap(page);
1061 write_data += from;
1062
1063 if ((to > PAGE_CACHE_SIZE) || (from > to)) {
1064 kunmap(page);
1065 return -EIO;
1066 }
1067
1068 /* racing with truncate? */
1069 if (offset > mapping->host->i_size) {
1070 kunmap(page);
1071 return 0; /* don't care */
1072 }
1073
1074 /* check to make sure that we are not extending the file */
1075 if (mapping->host->i_size - offset < (loff_t)to)
1076 to = (unsigned)(mapping->host->i_size - offset);
1077
1078 open_file = find_writable_file(CIFS_I(mapping->host), false);
1079 if (open_file) {
1080 bytes_written = cifs_write(open_file, open_file->pid,
1081 write_data, to - from, &offset);
1082 cifsFileInfo_put(open_file);
1083 /* Does mm or vfs already set times? */
1084 inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1085 if ((bytes_written > 0) && (offset))
1086 rc = 0;
1087 else if (bytes_written < 0)
1088 rc = bytes_written;
1089 } else {
1090 cFYI(1, "No writeable filehandles for inode");
1091 rc = -EIO;
1092 }
1093
1094 kunmap(page);
1095 return rc;
1096}
1097
1098static int cifs_writepages(struct address_space *mapping,
1099 struct writeback_control *wbc)
1100{
1101 struct cifs_sb_info *cifs_sb = CIFS_SB(mapping->host->i_sb);
1102 bool done = false, scanned = false, range_whole = false;
1103 pgoff_t end, index;
1104 struct cifs_writedata *wdata;
1105 struct page *page;
1106 int rc = 0;
1107
1108 /*
1109 * If wsize is smaller than the page cache size, default to writing
1110 * one page at a time via cifs_writepage
1111 */
1112 if (cifs_sb->wsize < PAGE_CACHE_SIZE)
1113 return generic_writepages(mapping, wbc);
1114
1115 if (wbc->range_cyclic) {
1116 index = mapping->writeback_index; /* Start from prev offset */
1117 end = -1;
1118 } else {
1119 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1120 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1121 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1122 range_whole = true;
1123 scanned = true;
1124 }
1125retry:
1126 while (!done && index <= end) {
1127 unsigned int i, nr_pages, found_pages;
1128 pgoff_t next = 0, tofind;
1129 struct page **pages;
1130
1131 tofind = min((cifs_sb->wsize / PAGE_CACHE_SIZE) - 1,
1132 end - index) + 1;
1133
1134 wdata = cifs_writedata_alloc((unsigned int)tofind);
1135 if (!wdata) {
1136 rc = -ENOMEM;
1137 break;
1138 }
1139
1140 /*
1141 * find_get_pages_tag seems to return a max of 256 on each
1142 * iteration, so we must call it several times in order to
1143 * fill the array or the wsize is effectively limited to
1144 * 256 * PAGE_CACHE_SIZE.
1145 */
1146 found_pages = 0;
1147 pages = wdata->pages;
1148 do {
1149 nr_pages = find_get_pages_tag(mapping, &index,
1150 PAGECACHE_TAG_DIRTY,
1151 tofind, pages);
1152 found_pages += nr_pages;
1153 tofind -= nr_pages;
1154 pages += nr_pages;
1155 } while (nr_pages && tofind && index <= end);
1156
1157 if (found_pages == 0) {
1158 kref_put(&wdata->refcount, cifs_writedata_release);
1159 break;
1160 }
1161
1162 nr_pages = 0;
1163 for (i = 0; i < found_pages; i++) {
1164 page = wdata->pages[i];
1165 /*
1166 * At this point we hold neither mapping->tree_lock nor
1167 * lock on the page itself: the page may be truncated or
1168 * invalidated (changing page->mapping to NULL), or even
1169 * swizzled back from swapper_space to tmpfs file
1170 * mapping
1171 */
1172
1173 if (nr_pages == 0)
1174 lock_page(page);
1175 else if (!trylock_page(page))
1176 break;
1177
1178 if (unlikely(page->mapping != mapping)) {
1179 unlock_page(page);
1180 break;
1181 }
1182
1183 if (!wbc->range_cyclic && page->index > end) {
1184 done = true;
1185 unlock_page(page);
1186 break;
1187 }
1188
1189 if (next && (page->index != next)) {
1190 /* Not next consecutive page */
1191 unlock_page(page);
1192 break;
1193 }
1194
1195 if (wbc->sync_mode != WB_SYNC_NONE)
1196 wait_on_page_writeback(page);
1197
1198 if (PageWriteback(page) ||
1199 !clear_page_dirty_for_io(page)) {
1200 unlock_page(page);
1201 break;
1202 }
1203
1204 /*
1205 * This actually clears the dirty bit in the radix tree.
1206 * See cifs_writepage() for more commentary.
1207 */
1208 set_page_writeback(page);
1209
1210 if (page_offset(page) >= mapping->host->i_size) {
1211 done = true;
1212 unlock_page(page);
1213 end_page_writeback(page);
1214 break;
1215 }
1216
1217 wdata->pages[i] = page;
1218 next = page->index + 1;
1219 ++nr_pages;
1220 }
1221
1222 /* reset index to refind any pages skipped */
1223 if (nr_pages == 0)
1224 index = wdata->pages[0]->index + 1;
1225
1226 /* put any pages we aren't going to use */
1227 for (i = nr_pages; i < found_pages; i++) {
1228 page_cache_release(wdata->pages[i]);
1229 wdata->pages[i] = NULL;
1230 }
1231
1232 /* nothing to write? */
1233 if (nr_pages == 0) {
1234 kref_put(&wdata->refcount, cifs_writedata_release);
1235 continue;
1236 }
1237
1238 wdata->sync_mode = wbc->sync_mode;
1239 wdata->nr_pages = nr_pages;
1240 wdata->offset = page_offset(wdata->pages[0]);
1241
1242 do {
1243 if (wdata->cfile != NULL)
1244 cifsFileInfo_put(wdata->cfile);
1245 wdata->cfile = find_writable_file(CIFS_I(mapping->host),
1246 false);
1247 if (!wdata->cfile) {
1248 cERROR(1, "No writable handles for inode");
1249 rc = -EBADF;
1250 break;
1251 }
1252 rc = cifs_async_writev(wdata);
1253 } while (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN);
1254
1255 for (i = 0; i < nr_pages; ++i)
1256 unlock_page(wdata->pages[i]);
1257
1258 /* send failure -- clean up the mess */
1259 if (rc != 0) {
1260 for (i = 0; i < nr_pages; ++i) {
1261 if (rc == -EAGAIN)
1262 redirty_page_for_writepage(wbc,
1263 wdata->pages[i]);
1264 else
1265 SetPageError(wdata->pages[i]);
1266 end_page_writeback(wdata->pages[i]);
1267 page_cache_release(wdata->pages[i]);
1268 }
1269 if (rc != -EAGAIN)
1270 mapping_set_error(mapping, rc);
1271 }
1272 kref_put(&wdata->refcount, cifs_writedata_release);
1273
1274 wbc->nr_to_write -= nr_pages;
1275 if (wbc->nr_to_write <= 0)
1276 done = true;
1277
1278 index = next;
1279 }
1280
1281 if (!scanned && !done) {
1282 /*
1283 * We hit the last page and there is more work to be done: wrap
1284 * back to the start of the file
1285 */
1286 scanned = true;
1287 index = 0;
1288 goto retry;
1289 }
1290
1291 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1292 mapping->writeback_index = index;
1293
1294 return rc;
1295}
1296
1297static int
1298cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
1299{
1300 int rc;
1301 int xid;
1302
1303 xid = GetXid();
1304/* BB add check for wbc flags */
1305 page_cache_get(page);
1306 if (!PageUptodate(page))
1307 cFYI(1, "ppw - page not up to date");
1308
1309 /*
1310 * Set the "writeback" flag, and clear "dirty" in the radix tree.
1311 *
1312 * A writepage() implementation always needs to do either this,
1313 * or re-dirty the page with "redirty_page_for_writepage()" in
1314 * the case of a failure.
1315 *
1316 * Just unlocking the page will cause the radix tree tag-bits
1317 * to fail to update with the state of the page correctly.
1318 */
1319 set_page_writeback(page);
1320retry_write:
1321 rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
1322 if (rc == -EAGAIN && wbc->sync_mode == WB_SYNC_ALL)
1323 goto retry_write;
1324 else if (rc == -EAGAIN)
1325 redirty_page_for_writepage(wbc, page);
1326 else if (rc != 0)
1327 SetPageError(page);
1328 else
1329 SetPageUptodate(page);
1330 end_page_writeback(page);
1331 page_cache_release(page);
1332 FreeXid(xid);
1333 return rc;
1334}
1335
1336static int cifs_writepage(struct page *page, struct writeback_control *wbc)
1337{
1338 int rc = cifs_writepage_locked(page, wbc);
1339 unlock_page(page);
1340 return rc;
1341}
1342
1343static int cifs_write_end(struct file *file, struct address_space *mapping,
1344 loff_t pos, unsigned len, unsigned copied,
1345 struct page *page, void *fsdata)
1346{
1347 int rc;
1348 struct inode *inode = mapping->host;
1349 struct cifsFileInfo *cfile = file->private_data;
1350 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
1351 __u32 pid;
1352
1353 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
1354 pid = cfile->pid;
1355 else
1356 pid = current->tgid;
1357
1358 cFYI(1, "write_end for page %p from pos %lld with %d bytes",
1359 page, pos, copied);
1360
1361 if (PageChecked(page)) {
1362 if (copied == len)
1363 SetPageUptodate(page);
1364 ClearPageChecked(page);
1365 } else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
1366 SetPageUptodate(page);
1367
1368 if (!PageUptodate(page)) {
1369 char *page_data;
1370 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
1371 int xid;
1372
1373 xid = GetXid();
1374 /* this is probably better than directly calling
1375 partialpage_write since in this function the file handle is
1376 known which we might as well leverage */
1377 /* BB check if anything else missing out of ppw
1378 such as updating last write time */
1379 page_data = kmap(page);
1380 rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
1381 /* if (rc < 0) should we set writebehind rc? */
1382 kunmap(page);
1383
1384 FreeXid(xid);
1385 } else {
1386 rc = copied;
1387 pos += copied;
1388 set_page_dirty(page);
1389 }
1390
1391 if (rc > 0) {
1392 spin_lock(&inode->i_lock);
1393 if (pos > inode->i_size)
1394 i_size_write(inode, pos);
1395 spin_unlock(&inode->i_lock);
1396 }
1397
1398 unlock_page(page);
1399 page_cache_release(page);
1400
1401 return rc;
1402}
1403
1404int cifs_strict_fsync(struct file *file, int datasync)
1405{
1406 int xid;
1407 int rc = 0;
1408 struct cifs_tcon *tcon;
1409 struct cifsFileInfo *smbfile = file->private_data;
1410 struct inode *inode = file->f_path.dentry->d_inode;
1411 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
1412
1413 xid = GetXid();
1414
1415 cFYI(1, "Sync file - name: %s datasync: 0x%x",
1416 file->f_path.dentry->d_name.name, datasync);
1417
1418 if (!CIFS_I(inode)->clientCanCacheRead) {
1419 rc = cifs_invalidate_mapping(inode);
1420 if (rc) {
1421 cFYI(1, "rc: %d during invalidate phase", rc);
1422 rc = 0; /* don't care about it in fsync */
1423 }
1424 }
1425
1426 tcon = tlink_tcon(smbfile->tlink);
1427 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
1428 rc = CIFSSMBFlush(xid, tcon, smbfile->netfid);
1429
1430 FreeXid(xid);
1431 return rc;
1432}
1433
1434int cifs_fsync(struct file *file, int datasync)
1435{
1436 int xid;
1437 int rc = 0;
1438 struct cifs_tcon *tcon;
1439 struct cifsFileInfo *smbfile = file->private_data;
1440 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1441
1442 xid = GetXid();
1443
1444 cFYI(1, "Sync file - name: %s datasync: 0x%x",
1445 file->f_path.dentry->d_name.name, datasync);
1446
1447 tcon = tlink_tcon(smbfile->tlink);
1448 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
1449 rc = CIFSSMBFlush(xid, tcon, smbfile->netfid);
1450
1451 FreeXid(xid);
1452 return rc;
1453}
1454
1455/*
1456 * As file closes, flush all cached write data for this inode checking
1457 * for write behind errors.
1458 */
1459int cifs_flush(struct file *file, fl_owner_t id)
1460{
1461 struct inode *inode = file->f_path.dentry->d_inode;
1462 int rc = 0;
1463
1464 if (file->f_mode & FMODE_WRITE)
1465 rc = filemap_write_and_wait(inode->i_mapping);
1466
1467 cFYI(1, "Flush inode %p file %p rc %d", inode, file, rc);
1468
1469 return rc;
1470}
1471
1472static int
1473cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
1474{
1475 int rc = 0;
1476 unsigned long i;
1477
1478 for (i = 0; i < num_pages; i++) {
1479 pages[i] = alloc_page(__GFP_HIGHMEM);
1480 if (!pages[i]) {
1481 /*
1482 * save number of pages we have already allocated and
1483 * return with ENOMEM error
1484 */
1485 num_pages = i;
1486 rc = -ENOMEM;
1487 goto error;
1488 }
1489 }
1490
1491 return rc;
1492
1493error:
1494 for (i = 0; i < num_pages; i++)
1495 put_page(pages[i]);
1496 return rc;
1497}
1498
1499static inline
1500size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
1501{
1502 size_t num_pages;
1503 size_t clen;
1504
1505 clen = min_t(const size_t, len, wsize);
1506 num_pages = clen / PAGE_CACHE_SIZE;
1507 if (clen % PAGE_CACHE_SIZE)
1508 num_pages++;
1509
1510 if (cur_len)
1511 *cur_len = clen;
1512
1513 return num_pages;
1514}
1515
1516static ssize_t
1517cifs_iovec_write(struct file *file, const struct iovec *iov,
1518 unsigned long nr_segs, loff_t *poffset)
1519{
1520 unsigned int written;
1521 unsigned long num_pages, npages, i;
1522 size_t copied, len, cur_len;
1523 ssize_t total_written = 0;
1524 struct kvec *to_send;
1525 struct page **pages;
1526 struct iov_iter it;
1527 struct inode *inode;
1528 struct cifsFileInfo *open_file;
1529 struct cifs_tcon *pTcon;
1530 struct cifs_sb_info *cifs_sb;
1531 struct cifs_io_parms io_parms;
1532 int xid, rc;
1533 __u32 pid;
1534
1535 len = iov_length(iov, nr_segs);
1536 if (!len)
1537 return 0;
1538
1539 rc = generic_write_checks(file, poffset, &len, 0);
1540 if (rc)
1541 return rc;
1542
1543 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1544 num_pages = get_numpages(cifs_sb->wsize, len, &cur_len);
1545
1546 pages = kmalloc(sizeof(struct pages *)*num_pages, GFP_KERNEL);
1547 if (!pages)
1548 return -ENOMEM;
1549
1550 to_send = kmalloc(sizeof(struct kvec)*(num_pages + 1), GFP_KERNEL);
1551 if (!to_send) {
1552 kfree(pages);
1553 return -ENOMEM;
1554 }
1555
1556 rc = cifs_write_allocate_pages(pages, num_pages);
1557 if (rc) {
1558 kfree(pages);
1559 kfree(to_send);
1560 return rc;
1561 }
1562
1563 xid = GetXid();
1564 open_file = file->private_data;
1565
1566 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
1567 pid = open_file->pid;
1568 else
1569 pid = current->tgid;
1570
1571 pTcon = tlink_tcon(open_file->tlink);
1572 inode = file->f_path.dentry->d_inode;
1573
1574 iov_iter_init(&it, iov, nr_segs, len, 0);
1575 npages = num_pages;
1576
1577 do {
1578 size_t save_len = cur_len;
1579 for (i = 0; i < npages; i++) {
1580 copied = min_t(const size_t, cur_len, PAGE_CACHE_SIZE);
1581 copied = iov_iter_copy_from_user(pages[i], &it, 0,
1582 copied);
1583 cur_len -= copied;
1584 iov_iter_advance(&it, copied);
1585 to_send[i+1].iov_base = kmap(pages[i]);
1586 to_send[i+1].iov_len = copied;
1587 }
1588
1589 cur_len = save_len - cur_len;
1590
1591 do {
1592 if (open_file->invalidHandle) {
1593 rc = cifs_reopen_file(open_file, false);
1594 if (rc != 0)
1595 break;
1596 }
1597 io_parms.netfid = open_file->netfid;
1598 io_parms.pid = pid;
1599 io_parms.tcon = pTcon;
1600 io_parms.offset = *poffset;
1601 io_parms.length = cur_len;
1602 rc = CIFSSMBWrite2(xid, &io_parms, &written, to_send,
1603 npages, 0);
1604 } while (rc == -EAGAIN);
1605
1606 for (i = 0; i < npages; i++)
1607 kunmap(pages[i]);
1608
1609 if (written) {
1610 len -= written;
1611 total_written += written;
1612 cifs_update_eof(CIFS_I(inode), *poffset, written);
1613 *poffset += written;
1614 } else if (rc < 0) {
1615 if (!total_written)
1616 total_written = rc;
1617 break;
1618 }
1619
1620 /* get length and number of kvecs of the next write */
1621 npages = get_numpages(cifs_sb->wsize, len, &cur_len);
1622 } while (len > 0);
1623
1624 if (total_written > 0) {
1625 spin_lock(&inode->i_lock);
1626 if (*poffset > inode->i_size)
1627 i_size_write(inode, *poffset);
1628 spin_unlock(&inode->i_lock);
1629 }
1630
1631 cifs_stats_bytes_written(pTcon, total_written);
1632 mark_inode_dirty_sync(inode);
1633
1634 for (i = 0; i < num_pages; i++)
1635 put_page(pages[i]);
1636 kfree(to_send);
1637 kfree(pages);
1638 FreeXid(xid);
1639 return total_written;
1640}
1641
1642ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
1643 unsigned long nr_segs, loff_t pos)
1644{
1645 ssize_t written;
1646 struct inode *inode;
1647
1648 inode = iocb->ki_filp->f_path.dentry->d_inode;
1649
1650 /*
1651 * BB - optimize the way when signing is disabled. We can drop this
1652 * extra memory-to-memory copying and use iovec buffers for constructing
1653 * write request.
1654 */
1655
1656 written = cifs_iovec_write(iocb->ki_filp, iov, nr_segs, &pos);
1657 if (written > 0) {
1658 CIFS_I(inode)->invalid_mapping = true;
1659 iocb->ki_pos = pos;
1660 }
1661
1662 return written;
1663}
1664
1665ssize_t cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
1666 unsigned long nr_segs, loff_t pos)
1667{
1668 struct inode *inode;
1669
1670 inode = iocb->ki_filp->f_path.dentry->d_inode;
1671
1672 if (CIFS_I(inode)->clientCanCacheAll)
1673 return generic_file_aio_write(iocb, iov, nr_segs, pos);
1674
1675 /*
1676 * In strict cache mode we need to write the data to the server exactly
1677 * from the pos to pos+len-1 rather than flush all affected pages
1678 * because it may cause a error with mandatory locks on these pages but
1679 * not on the region from pos to ppos+len-1.
1680 */
1681
1682 return cifs_user_writev(iocb, iov, nr_segs, pos);
1683}
1684
1685static ssize_t
1686cifs_iovec_read(struct file *file, const struct iovec *iov,
1687 unsigned long nr_segs, loff_t *poffset)
1688{
1689 int rc;
1690 int xid;
1691 ssize_t total_read;
1692 unsigned int bytes_read = 0;
1693 size_t len, cur_len;
1694 int iov_offset = 0;
1695 struct cifs_sb_info *cifs_sb;
1696 struct cifs_tcon *pTcon;
1697 struct cifsFileInfo *open_file;
1698 struct smb_com_read_rsp *pSMBr;
1699 struct cifs_io_parms io_parms;
1700 char *read_data;
1701 __u32 pid;
1702
1703 if (!nr_segs)
1704 return 0;
1705
1706 len = iov_length(iov, nr_segs);
1707 if (!len)
1708 return 0;
1709
1710 xid = GetXid();
1711 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1712
1713 open_file = file->private_data;
1714 pTcon = tlink_tcon(open_file->tlink);
1715
1716 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
1717 pid = open_file->pid;
1718 else
1719 pid = current->tgid;
1720
1721 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1722 cFYI(1, "attempting read on write only file instance");
1723
1724 for (total_read = 0; total_read < len; total_read += bytes_read) {
1725 cur_len = min_t(const size_t, len - total_read, cifs_sb->rsize);
1726 rc = -EAGAIN;
1727 read_data = NULL;
1728
1729 while (rc == -EAGAIN) {
1730 int buf_type = CIFS_NO_BUFFER;
1731 if (open_file->invalidHandle) {
1732 rc = cifs_reopen_file(open_file, true);
1733 if (rc != 0)
1734 break;
1735 }
1736 io_parms.netfid = open_file->netfid;
1737 io_parms.pid = pid;
1738 io_parms.tcon = pTcon;
1739 io_parms.offset = *poffset;
1740 io_parms.length = cur_len;
1741 rc = CIFSSMBRead(xid, &io_parms, &bytes_read,
1742 &read_data, &buf_type);
1743 pSMBr = (struct smb_com_read_rsp *)read_data;
1744 if (read_data) {
1745 char *data_offset = read_data + 4 +
1746 le16_to_cpu(pSMBr->DataOffset);
1747 if (memcpy_toiovecend(iov, data_offset,
1748 iov_offset, bytes_read))
1749 rc = -EFAULT;
1750 if (buf_type == CIFS_SMALL_BUFFER)
1751 cifs_small_buf_release(read_data);
1752 else if (buf_type == CIFS_LARGE_BUFFER)
1753 cifs_buf_release(read_data);
1754 read_data = NULL;
1755 iov_offset += bytes_read;
1756 }
1757 }
1758
1759 if (rc || (bytes_read == 0)) {
1760 if (total_read) {
1761 break;
1762 } else {
1763 FreeXid(xid);
1764 return rc;
1765 }
1766 } else {
1767 cifs_stats_bytes_read(pTcon, bytes_read);
1768 *poffset += bytes_read;
1769 }
1770 }
1771
1772 FreeXid(xid);
1773 return total_read;
1774}
1775
1776ssize_t cifs_user_readv(struct kiocb *iocb, const struct iovec *iov,
1777 unsigned long nr_segs, loff_t pos)
1778{
1779 ssize_t read;
1780
1781 read = cifs_iovec_read(iocb->ki_filp, iov, nr_segs, &pos);
1782 if (read > 0)
1783 iocb->ki_pos = pos;
1784
1785 return read;
1786}
1787
1788ssize_t cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
1789 unsigned long nr_segs, loff_t pos)
1790{
1791 struct inode *inode;
1792
1793 inode = iocb->ki_filp->f_path.dentry->d_inode;
1794
1795 if (CIFS_I(inode)->clientCanCacheRead)
1796 return generic_file_aio_read(iocb, iov, nr_segs, pos);
1797
1798 /*
1799 * In strict cache mode we need to read from the server all the time
1800 * if we don't have level II oplock because the server can delay mtime
1801 * change - so we can't make a decision about inode invalidating.
1802 * And we can also fail with pagereading if there are mandatory locks
1803 * on pages affected by this read but not on the region from pos to
1804 * pos+len-1.
1805 */
1806
1807 return cifs_user_readv(iocb, iov, nr_segs, pos);
1808}
1809
1810static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
1811 loff_t *poffset)
1812{
1813 int rc = -EACCES;
1814 unsigned int bytes_read = 0;
1815 unsigned int total_read;
1816 unsigned int current_read_size;
1817 struct cifs_sb_info *cifs_sb;
1818 struct cifs_tcon *pTcon;
1819 int xid;
1820 char *current_offset;
1821 struct cifsFileInfo *open_file;
1822 struct cifs_io_parms io_parms;
1823 int buf_type = CIFS_NO_BUFFER;
1824 __u32 pid;
1825
1826 xid = GetXid();
1827 cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
1828
1829 if (file->private_data == NULL) {
1830 rc = -EBADF;
1831 FreeXid(xid);
1832 return rc;
1833 }
1834 open_file = file->private_data;
1835 pTcon = tlink_tcon(open_file->tlink);
1836
1837 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
1838 pid = open_file->pid;
1839 else
1840 pid = current->tgid;
1841
1842 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1843 cFYI(1, "attempting read on write only file instance");
1844
1845 for (total_read = 0, current_offset = read_data;
1846 read_size > total_read;
1847 total_read += bytes_read, current_offset += bytes_read) {
1848 current_read_size = min_t(const int, read_size - total_read,
1849 cifs_sb->rsize);
1850 /* For windows me and 9x we do not want to request more
1851 than it negotiated since it will refuse the read then */
1852 if ((pTcon->ses) &&
1853 !(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
1854 current_read_size = min_t(const int, current_read_size,
1855 pTcon->ses->server->maxBuf - 128);
1856 }
1857 rc = -EAGAIN;
1858 while (rc == -EAGAIN) {
1859 if (open_file->invalidHandle) {
1860 rc = cifs_reopen_file(open_file, true);
1861 if (rc != 0)
1862 break;
1863 }
1864 io_parms.netfid = open_file->netfid;
1865 io_parms.pid = pid;
1866 io_parms.tcon = pTcon;
1867 io_parms.offset = *poffset;
1868 io_parms.length = current_read_size;
1869 rc = CIFSSMBRead(xid, &io_parms, &bytes_read,
1870 ¤t_offset, &buf_type);
1871 }
1872 if (rc || (bytes_read == 0)) {
1873 if (total_read) {
1874 break;
1875 } else {
1876 FreeXid(xid);
1877 return rc;
1878 }
1879 } else {
1880 cifs_stats_bytes_read(pTcon, total_read);
1881 *poffset += bytes_read;
1882 }
1883 }
1884 FreeXid(xid);
1885 return total_read;
1886}
1887
1888/*
1889 * If the page is mmap'ed into a process' page tables, then we need to make
1890 * sure that it doesn't change while being written back.
1891 */
1892static int
1893cifs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
1894{
1895 struct page *page = vmf->page;
1896
1897 lock_page(page);
1898 return VM_FAULT_LOCKED;
1899}
1900
1901static struct vm_operations_struct cifs_file_vm_ops = {
1902 .fault = filemap_fault,
1903 .page_mkwrite = cifs_page_mkwrite,
1904};
1905
1906int cifs_file_strict_mmap(struct file *file, struct…Large files files are truncated, but you can click here to view the full file