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[mirror_ubuntu-bionic-kernel.git] / fs / cifs / file.c
1 /*
2 * fs/cifs/file.c
3 *
4 * vfs operations that deal with files
5 *
6 * Copyright (C) International Business Machines Corp., 2002,2010
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
47 static inline int cifs_convert_flags(unsigned int flags)
48 {
49 if ((flags & O_ACCMODE) == O_RDONLY)
50 return GENERIC_READ;
51 else if ((flags & O_ACCMODE) == O_WRONLY)
52 return GENERIC_WRITE;
53 else if ((flags & O_ACCMODE) == O_RDWR) {
54 /* GENERIC_ALL is too much permission to request
55 can cause unnecessary access denied on create */
56 /* return GENERIC_ALL; */
57 return (GENERIC_READ | GENERIC_WRITE);
58 }
59
60 return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
61 FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
62 FILE_READ_DATA);
63 }
64
65 static u32 cifs_posix_convert_flags(unsigned int flags)
66 {
67 u32 posix_flags = 0;
68
69 if ((flags & O_ACCMODE) == O_RDONLY)
70 posix_flags = SMB_O_RDONLY;
71 else if ((flags & O_ACCMODE) == O_WRONLY)
72 posix_flags = SMB_O_WRONLY;
73 else if ((flags & O_ACCMODE) == O_RDWR)
74 posix_flags = SMB_O_RDWR;
75
76 if (flags & O_CREAT) {
77 posix_flags |= SMB_O_CREAT;
78 if (flags & O_EXCL)
79 posix_flags |= SMB_O_EXCL;
80 } else if (flags & O_EXCL)
81 cifs_dbg(FYI, "Application %s pid %d has incorrectly set O_EXCL flag but not O_CREAT on file open. Ignoring O_EXCL\n",
82 current->comm, current->tgid);
83
84 if (flags & O_TRUNC)
85 posix_flags |= SMB_O_TRUNC;
86 /* be safe and imply O_SYNC for O_DSYNC */
87 if (flags & O_DSYNC)
88 posix_flags |= SMB_O_SYNC;
89 if (flags & O_DIRECTORY)
90 posix_flags |= SMB_O_DIRECTORY;
91 if (flags & O_NOFOLLOW)
92 posix_flags |= SMB_O_NOFOLLOW;
93 if (flags & O_DIRECT)
94 posix_flags |= SMB_O_DIRECT;
95
96 return posix_flags;
97 }
98
99 static inline int cifs_get_disposition(unsigned int flags)
100 {
101 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
102 return FILE_CREATE;
103 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
104 return FILE_OVERWRITE_IF;
105 else if ((flags & O_CREAT) == O_CREAT)
106 return FILE_OPEN_IF;
107 else if ((flags & O_TRUNC) == O_TRUNC)
108 return FILE_OVERWRITE;
109 else
110 return FILE_OPEN;
111 }
112
113 int cifs_posix_open(char *full_path, struct inode **pinode,
114 struct super_block *sb, int mode, unsigned int f_flags,
115 __u32 *poplock, __u16 *pnetfid, unsigned int xid)
116 {
117 int rc;
118 FILE_UNIX_BASIC_INFO *presp_data;
119 __u32 posix_flags = 0;
120 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
121 struct cifs_fattr fattr;
122 struct tcon_link *tlink;
123 struct cifs_tcon *tcon;
124
125 cifs_dbg(FYI, "posix open %s\n", full_path);
126
127 presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
128 if (presp_data == NULL)
129 return -ENOMEM;
130
131 tlink = cifs_sb_tlink(cifs_sb);
132 if (IS_ERR(tlink)) {
133 rc = PTR_ERR(tlink);
134 goto posix_open_ret;
135 }
136
137 tcon = tlink_tcon(tlink);
138 mode &= ~current_umask();
139
140 posix_flags = cifs_posix_convert_flags(f_flags);
141 rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
142 poplock, full_path, cifs_sb->local_nls,
143 cifs_remap(cifs_sb));
144 cifs_put_tlink(tlink);
145
146 if (rc)
147 goto posix_open_ret;
148
149 if (presp_data->Type == cpu_to_le32(-1))
150 goto posix_open_ret; /* open ok, caller does qpathinfo */
151
152 if (!pinode)
153 goto posix_open_ret; /* caller does not need info */
154
155 cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
156
157 /* get new inode and set it up */
158 if (*pinode == NULL) {
159 cifs_fill_uniqueid(sb, &fattr);
160 *pinode = cifs_iget(sb, &fattr);
161 if (!*pinode) {
162 rc = -ENOMEM;
163 goto posix_open_ret;
164 }
165 } else {
166 cifs_fattr_to_inode(*pinode, &fattr);
167 }
168
169 posix_open_ret:
170 kfree(presp_data);
171 return rc;
172 }
173
174 static int
175 cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
176 struct cifs_tcon *tcon, unsigned int f_flags, __u32 *oplock,
177 struct cifs_fid *fid, unsigned int xid)
178 {
179 int rc;
180 int desired_access;
181 int disposition;
182 int create_options = CREATE_NOT_DIR;
183 FILE_ALL_INFO *buf;
184 struct TCP_Server_Info *server = tcon->ses->server;
185 struct cifs_open_parms oparms;
186
187 if (!server->ops->open)
188 return -ENOSYS;
189
190 desired_access = cifs_convert_flags(f_flags);
191
192 /*********************************************************************
193 * open flag mapping table:
194 *
195 * POSIX Flag CIFS Disposition
196 * ---------- ----------------
197 * O_CREAT FILE_OPEN_IF
198 * O_CREAT | O_EXCL FILE_CREATE
199 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
200 * O_TRUNC FILE_OVERWRITE
201 * none of the above FILE_OPEN
202 *
203 * Note that there is not a direct match between disposition
204 * FILE_SUPERSEDE (ie create whether or not file exists although
205 * O_CREAT | O_TRUNC is similar but truncates the existing
206 * file rather than creating a new file as FILE_SUPERSEDE does
207 * (which uses the attributes / metadata passed in on open call)
208 *?
209 *? O_SYNC is a reasonable match to CIFS writethrough flag
210 *? and the read write flags match reasonably. O_LARGEFILE
211 *? is irrelevant because largefile support is always used
212 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
213 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
214 *********************************************************************/
215
216 disposition = cifs_get_disposition(f_flags);
217
218 /* BB pass O_SYNC flag through on file attributes .. BB */
219
220 buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
221 if (!buf)
222 return -ENOMEM;
223
224 if (backup_cred(cifs_sb))
225 create_options |= CREATE_OPEN_BACKUP_INTENT;
226
227 /* O_SYNC also has bit for O_DSYNC so following check picks up either */
228 if (f_flags & O_SYNC)
229 create_options |= CREATE_WRITE_THROUGH;
230
231 if (f_flags & O_DIRECT)
232 create_options |= CREATE_NO_BUFFER;
233
234 oparms.tcon = tcon;
235 oparms.cifs_sb = cifs_sb;
236 oparms.desired_access = desired_access;
237 oparms.create_options = create_options;
238 oparms.disposition = disposition;
239 oparms.path = full_path;
240 oparms.fid = fid;
241 oparms.reconnect = false;
242
243 rc = server->ops->open(xid, &oparms, oplock, buf);
244
245 if (rc)
246 goto out;
247
248 if (tcon->unix_ext)
249 rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
250 xid);
251 else
252 rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
253 xid, fid);
254
255 out:
256 kfree(buf);
257 return rc;
258 }
259
260 static bool
261 cifs_has_mand_locks(struct cifsInodeInfo *cinode)
262 {
263 struct cifs_fid_locks *cur;
264 bool has_locks = false;
265
266 down_read(&cinode->lock_sem);
267 list_for_each_entry(cur, &cinode->llist, llist) {
268 if (!list_empty(&cur->locks)) {
269 has_locks = true;
270 break;
271 }
272 }
273 up_read(&cinode->lock_sem);
274 return has_locks;
275 }
276
277 struct cifsFileInfo *
278 cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
279 struct tcon_link *tlink, __u32 oplock)
280 {
281 struct dentry *dentry = file_dentry(file);
282 struct inode *inode = d_inode(dentry);
283 struct cifsInodeInfo *cinode = CIFS_I(inode);
284 struct cifsFileInfo *cfile;
285 struct cifs_fid_locks *fdlocks;
286 struct cifs_tcon *tcon = tlink_tcon(tlink);
287 struct TCP_Server_Info *server = tcon->ses->server;
288
289 cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
290 if (cfile == NULL)
291 return cfile;
292
293 fdlocks = kzalloc(sizeof(struct cifs_fid_locks), GFP_KERNEL);
294 if (!fdlocks) {
295 kfree(cfile);
296 return NULL;
297 }
298
299 INIT_LIST_HEAD(&fdlocks->locks);
300 fdlocks->cfile = cfile;
301 cfile->llist = fdlocks;
302 down_write(&cinode->lock_sem);
303 list_add(&fdlocks->llist, &cinode->llist);
304 up_write(&cinode->lock_sem);
305
306 cfile->count = 1;
307 cfile->pid = current->tgid;
308 cfile->uid = current_fsuid();
309 cfile->dentry = dget(dentry);
310 cfile->f_flags = file->f_flags;
311 cfile->invalidHandle = false;
312 cfile->tlink = cifs_get_tlink(tlink);
313 INIT_WORK(&cfile->oplock_break, cifs_oplock_break);
314 mutex_init(&cfile->fh_mutex);
315 spin_lock_init(&cfile->file_info_lock);
316
317 cifs_sb_active(inode->i_sb);
318
319 /*
320 * If the server returned a read oplock and we have mandatory brlocks,
321 * set oplock level to None.
322 */
323 if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
324 cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
325 oplock = 0;
326 }
327
328 spin_lock(&tcon->open_file_lock);
329 if (fid->pending_open->oplock != CIFS_OPLOCK_NO_CHANGE && oplock)
330 oplock = fid->pending_open->oplock;
331 list_del(&fid->pending_open->olist);
332
333 fid->purge_cache = false;
334 server->ops->set_fid(cfile, fid, oplock);
335
336 list_add(&cfile->tlist, &tcon->openFileList);
337
338 /* if readable file instance put first in list*/
339 if (file->f_mode & FMODE_READ)
340 list_add(&cfile->flist, &cinode->openFileList);
341 else
342 list_add_tail(&cfile->flist, &cinode->openFileList);
343 spin_unlock(&tcon->open_file_lock);
344
345 if (fid->purge_cache)
346 cifs_zap_mapping(inode);
347
348 file->private_data = cfile;
349 return cfile;
350 }
351
352 struct cifsFileInfo *
353 cifsFileInfo_get(struct cifsFileInfo *cifs_file)
354 {
355 spin_lock(&cifs_file->file_info_lock);
356 cifsFileInfo_get_locked(cifs_file);
357 spin_unlock(&cifs_file->file_info_lock);
358 return cifs_file;
359 }
360
361 /*
362 * Release a reference on the file private data. This may involve closing
363 * the filehandle out on the server. Must be called without holding
364 * tcon->open_file_lock and cifs_file->file_info_lock.
365 */
366 void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
367 {
368 struct inode *inode = d_inode(cifs_file->dentry);
369 struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink);
370 struct TCP_Server_Info *server = tcon->ses->server;
371 struct cifsInodeInfo *cifsi = CIFS_I(inode);
372 struct super_block *sb = inode->i_sb;
373 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
374 struct cifsLockInfo *li, *tmp;
375 struct cifs_fid fid;
376 struct cifs_pending_open open;
377 bool oplock_break_cancelled;
378
379 spin_lock(&tcon->open_file_lock);
380
381 spin_lock(&cifs_file->file_info_lock);
382 if (--cifs_file->count > 0) {
383 spin_unlock(&cifs_file->file_info_lock);
384 spin_unlock(&tcon->open_file_lock);
385 return;
386 }
387 spin_unlock(&cifs_file->file_info_lock);
388
389 if (server->ops->get_lease_key)
390 server->ops->get_lease_key(inode, &fid);
391
392 /* store open in pending opens to make sure we don't miss lease break */
393 cifs_add_pending_open_locked(&fid, cifs_file->tlink, &open);
394
395 /* remove it from the lists */
396 list_del(&cifs_file->flist);
397 list_del(&cifs_file->tlist);
398
399 if (list_empty(&cifsi->openFileList)) {
400 cifs_dbg(FYI, "closing last open instance for inode %p\n",
401 d_inode(cifs_file->dentry));
402 /*
403 * In strict cache mode we need invalidate mapping on the last
404 * close because it may cause a error when we open this file
405 * again and get at least level II oplock.
406 */
407 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
408 set_bit(CIFS_INO_INVALID_MAPPING, &cifsi->flags);
409 cifs_set_oplock_level(cifsi, 0);
410 }
411
412 spin_unlock(&tcon->open_file_lock);
413
414 oplock_break_cancelled = cancel_work_sync(&cifs_file->oplock_break);
415
416 if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
417 struct TCP_Server_Info *server = tcon->ses->server;
418 unsigned int xid;
419
420 xid = get_xid();
421 if (server->ops->close)
422 server->ops->close(xid, tcon, &cifs_file->fid);
423 _free_xid(xid);
424 }
425
426 if (oplock_break_cancelled)
427 cifs_done_oplock_break(cifsi);
428
429 cifs_del_pending_open(&open);
430
431 /*
432 * Delete any outstanding lock records. We'll lose them when the file
433 * is closed anyway.
434 */
435 down_write(&cifsi->lock_sem);
436 list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
437 list_del(&li->llist);
438 cifs_del_lock_waiters(li);
439 kfree(li);
440 }
441 list_del(&cifs_file->llist->llist);
442 kfree(cifs_file->llist);
443 up_write(&cifsi->lock_sem);
444
445 cifs_put_tlink(cifs_file->tlink);
446 dput(cifs_file->dentry);
447 cifs_sb_deactive(sb);
448 kfree(cifs_file);
449 }
450
451 int cifs_open(struct inode *inode, struct file *file)
452
453 {
454 int rc = -EACCES;
455 unsigned int xid;
456 __u32 oplock;
457 struct cifs_sb_info *cifs_sb;
458 struct TCP_Server_Info *server;
459 struct cifs_tcon *tcon;
460 struct tcon_link *tlink;
461 struct cifsFileInfo *cfile = NULL;
462 char *full_path = NULL;
463 bool posix_open_ok = false;
464 struct cifs_fid fid;
465 struct cifs_pending_open open;
466
467 xid = get_xid();
468
469 cifs_sb = CIFS_SB(inode->i_sb);
470 tlink = cifs_sb_tlink(cifs_sb);
471 if (IS_ERR(tlink)) {
472 free_xid(xid);
473 return PTR_ERR(tlink);
474 }
475 tcon = tlink_tcon(tlink);
476 server = tcon->ses->server;
477
478 full_path = build_path_from_dentry(file_dentry(file));
479 if (full_path == NULL) {
480 rc = -ENOMEM;
481 goto out;
482 }
483
484 cifs_dbg(FYI, "inode = 0x%p file flags are 0x%x for %s\n",
485 inode, file->f_flags, full_path);
486
487 if (file->f_flags & O_DIRECT &&
488 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
489 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
490 file->f_op = &cifs_file_direct_nobrl_ops;
491 else
492 file->f_op = &cifs_file_direct_ops;
493 }
494
495 if (server->oplocks)
496 oplock = REQ_OPLOCK;
497 else
498 oplock = 0;
499
500 if (!tcon->broken_posix_open && tcon->unix_ext &&
501 cap_unix(tcon->ses) && (CIFS_UNIX_POSIX_PATH_OPS_CAP &
502 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
503 /* can not refresh inode info since size could be stale */
504 rc = cifs_posix_open(full_path, &inode, inode->i_sb,
505 cifs_sb->mnt_file_mode /* ignored */,
506 file->f_flags, &oplock, &fid.netfid, xid);
507 if (rc == 0) {
508 cifs_dbg(FYI, "posix open succeeded\n");
509 posix_open_ok = true;
510 } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
511 if (tcon->ses->serverNOS)
512 cifs_dbg(VFS, "server %s of type %s returned unexpected error on SMB posix open, disabling posix open support. Check if server update available.\n",
513 tcon->ses->serverName,
514 tcon->ses->serverNOS);
515 tcon->broken_posix_open = true;
516 } else if ((rc != -EIO) && (rc != -EREMOTE) &&
517 (rc != -EOPNOTSUPP)) /* path not found or net err */
518 goto out;
519 /*
520 * Else fallthrough to retry open the old way on network i/o
521 * or DFS errors.
522 */
523 }
524
525 if (server->ops->get_lease_key)
526 server->ops->get_lease_key(inode, &fid);
527
528 cifs_add_pending_open(&fid, tlink, &open);
529
530 if (!posix_open_ok) {
531 if (server->ops->get_lease_key)
532 server->ops->get_lease_key(inode, &fid);
533
534 rc = cifs_nt_open(full_path, inode, cifs_sb, tcon,
535 file->f_flags, &oplock, &fid, xid);
536 if (rc) {
537 cifs_del_pending_open(&open);
538 goto out;
539 }
540 }
541
542 cfile = cifs_new_fileinfo(&fid, file, tlink, oplock);
543 if (cfile == NULL) {
544 if (server->ops->close)
545 server->ops->close(xid, tcon, &fid);
546 cifs_del_pending_open(&open);
547 rc = -ENOMEM;
548 goto out;
549 }
550
551 cifs_fscache_set_inode_cookie(inode, file);
552
553 if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
554 /*
555 * Time to set mode which we can not set earlier due to
556 * problems creating new read-only files.
557 */
558 struct cifs_unix_set_info_args args = {
559 .mode = inode->i_mode,
560 .uid = INVALID_UID, /* no change */
561 .gid = INVALID_GID, /* no change */
562 .ctime = NO_CHANGE_64,
563 .atime = NO_CHANGE_64,
564 .mtime = NO_CHANGE_64,
565 .device = 0,
566 };
567 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid.netfid,
568 cfile->pid);
569 }
570
571 out:
572 kfree(full_path);
573 free_xid(xid);
574 cifs_put_tlink(tlink);
575 return rc;
576 }
577
578 static int cifs_push_posix_locks(struct cifsFileInfo *cfile);
579
580 /*
581 * Try to reacquire byte range locks that were released when session
582 * to server was lost.
583 */
584 static int
585 cifs_relock_file(struct cifsFileInfo *cfile)
586 {
587 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
588 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
589 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
590 int rc = 0;
591
592 down_read_nested(&cinode->lock_sem, SINGLE_DEPTH_NESTING);
593 if (cinode->can_cache_brlcks) {
594 /* can cache locks - no need to relock */
595 up_read(&cinode->lock_sem);
596 return rc;
597 }
598
599 if (cap_unix(tcon->ses) &&
600 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
601 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
602 rc = cifs_push_posix_locks(cfile);
603 else
604 rc = tcon->ses->server->ops->push_mand_locks(cfile);
605
606 up_read(&cinode->lock_sem);
607 return rc;
608 }
609
610 static int
611 cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
612 {
613 int rc = -EACCES;
614 unsigned int xid;
615 __u32 oplock;
616 struct cifs_sb_info *cifs_sb;
617 struct cifs_tcon *tcon;
618 struct TCP_Server_Info *server;
619 struct cifsInodeInfo *cinode;
620 struct inode *inode;
621 char *full_path = NULL;
622 int desired_access;
623 int disposition = FILE_OPEN;
624 int create_options = CREATE_NOT_DIR;
625 struct cifs_open_parms oparms;
626
627 xid = get_xid();
628 mutex_lock(&cfile->fh_mutex);
629 if (!cfile->invalidHandle) {
630 mutex_unlock(&cfile->fh_mutex);
631 rc = 0;
632 free_xid(xid);
633 return rc;
634 }
635
636 inode = d_inode(cfile->dentry);
637 cifs_sb = CIFS_SB(inode->i_sb);
638 tcon = tlink_tcon(cfile->tlink);
639 server = tcon->ses->server;
640
641 /*
642 * Can not grab rename sem here because various ops, including those
643 * that already have the rename sem can end up causing writepage to get
644 * called and if the server was down that means we end up here, and we
645 * can never tell if the caller already has the rename_sem.
646 */
647 full_path = build_path_from_dentry(cfile->dentry);
648 if (full_path == NULL) {
649 rc = -ENOMEM;
650 mutex_unlock(&cfile->fh_mutex);
651 free_xid(xid);
652 return rc;
653 }
654
655 cifs_dbg(FYI, "inode = 0x%p file flags 0x%x for %s\n",
656 inode, cfile->f_flags, full_path);
657
658 if (tcon->ses->server->oplocks)
659 oplock = REQ_OPLOCK;
660 else
661 oplock = 0;
662
663 if (tcon->unix_ext && cap_unix(tcon->ses) &&
664 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
665 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
666 /*
667 * O_CREAT, O_EXCL and O_TRUNC already had their effect on the
668 * original open. Must mask them off for a reopen.
669 */
670 unsigned int oflags = cfile->f_flags &
671 ~(O_CREAT | O_EXCL | O_TRUNC);
672
673 rc = cifs_posix_open(full_path, NULL, inode->i_sb,
674 cifs_sb->mnt_file_mode /* ignored */,
675 oflags, &oplock, &cfile->fid.netfid, xid);
676 if (rc == 0) {
677 cifs_dbg(FYI, "posix reopen succeeded\n");
678 oparms.reconnect = true;
679 goto reopen_success;
680 }
681 /*
682 * fallthrough to retry open the old way on errors, especially
683 * in the reconnect path it is important to retry hard
684 */
685 }
686
687 desired_access = cifs_convert_flags(cfile->f_flags);
688
689 if (backup_cred(cifs_sb))
690 create_options |= CREATE_OPEN_BACKUP_INTENT;
691
692 if (server->ops->get_lease_key)
693 server->ops->get_lease_key(inode, &cfile->fid);
694
695 oparms.tcon = tcon;
696 oparms.cifs_sb = cifs_sb;
697 oparms.desired_access = desired_access;
698 oparms.create_options = create_options;
699 oparms.disposition = disposition;
700 oparms.path = full_path;
701 oparms.fid = &cfile->fid;
702 oparms.reconnect = true;
703
704 /*
705 * Can not refresh inode by passing in file_info buf to be returned by
706 * ops->open and then calling get_inode_info with returned buf since
707 * file might have write behind data that needs to be flushed and server
708 * version of file size can be stale. If we knew for sure that inode was
709 * not dirty locally we could do this.
710 */
711 rc = server->ops->open(xid, &oparms, &oplock, NULL);
712 if (rc == -ENOENT && oparms.reconnect == false) {
713 /* durable handle timeout is expired - open the file again */
714 rc = server->ops->open(xid, &oparms, &oplock, NULL);
715 /* indicate that we need to relock the file */
716 oparms.reconnect = true;
717 }
718
719 if (rc) {
720 mutex_unlock(&cfile->fh_mutex);
721 cifs_dbg(FYI, "cifs_reopen returned 0x%x\n", rc);
722 cifs_dbg(FYI, "oplock: %d\n", oplock);
723 goto reopen_error_exit;
724 }
725
726 reopen_success:
727 cfile->invalidHandle = false;
728 mutex_unlock(&cfile->fh_mutex);
729 cinode = CIFS_I(inode);
730
731 if (can_flush) {
732 rc = filemap_write_and_wait(inode->i_mapping);
733 mapping_set_error(inode->i_mapping, rc);
734
735 if (tcon->unix_ext)
736 rc = cifs_get_inode_info_unix(&inode, full_path,
737 inode->i_sb, xid);
738 else
739 rc = cifs_get_inode_info(&inode, full_path, NULL,
740 inode->i_sb, xid, NULL);
741 }
742 /*
743 * Else we are writing out data to server already and could deadlock if
744 * we tried to flush data, and since we do not know if we have data that
745 * would invalidate the current end of file on the server we can not go
746 * to the server to get the new inode info.
747 */
748
749 /*
750 * If the server returned a read oplock and we have mandatory brlocks,
751 * set oplock level to None.
752 */
753 if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
754 cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
755 oplock = 0;
756 }
757
758 server->ops->set_fid(cfile, &cfile->fid, oplock);
759 if (oparms.reconnect)
760 cifs_relock_file(cfile);
761
762 reopen_error_exit:
763 kfree(full_path);
764 free_xid(xid);
765 return rc;
766 }
767
768 int cifs_close(struct inode *inode, struct file *file)
769 {
770 if (file->private_data != NULL) {
771 cifsFileInfo_put(file->private_data);
772 file->private_data = NULL;
773 }
774
775 /* return code from the ->release op is always ignored */
776 return 0;
777 }
778
779 void
780 cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
781 {
782 struct cifsFileInfo *open_file;
783 struct list_head *tmp;
784 struct list_head *tmp1;
785 struct list_head tmp_list;
786
787 if (!tcon->use_persistent || !tcon->need_reopen_files)
788 return;
789
790 tcon->need_reopen_files = false;
791
792 cifs_dbg(FYI, "Reopen persistent handles");
793 INIT_LIST_HEAD(&tmp_list);
794
795 /* list all files open on tree connection, reopen resilient handles */
796 spin_lock(&tcon->open_file_lock);
797 list_for_each(tmp, &tcon->openFileList) {
798 open_file = list_entry(tmp, struct cifsFileInfo, tlist);
799 if (!open_file->invalidHandle)
800 continue;
801 cifsFileInfo_get(open_file);
802 list_add_tail(&open_file->rlist, &tmp_list);
803 }
804 spin_unlock(&tcon->open_file_lock);
805
806 list_for_each_safe(tmp, tmp1, &tmp_list) {
807 open_file = list_entry(tmp, struct cifsFileInfo, rlist);
808 if (cifs_reopen_file(open_file, false /* do not flush */))
809 tcon->need_reopen_files = true;
810 list_del_init(&open_file->rlist);
811 cifsFileInfo_put(open_file);
812 }
813 }
814
815 int cifs_closedir(struct inode *inode, struct file *file)
816 {
817 int rc = 0;
818 unsigned int xid;
819 struct cifsFileInfo *cfile = file->private_data;
820 struct cifs_tcon *tcon;
821 struct TCP_Server_Info *server;
822 char *buf;
823
824 cifs_dbg(FYI, "Closedir inode = 0x%p\n", inode);
825
826 if (cfile == NULL)
827 return rc;
828
829 xid = get_xid();
830 tcon = tlink_tcon(cfile->tlink);
831 server = tcon->ses->server;
832
833 cifs_dbg(FYI, "Freeing private data in close dir\n");
834 spin_lock(&cfile->file_info_lock);
835 if (server->ops->dir_needs_close(cfile)) {
836 cfile->invalidHandle = true;
837 spin_unlock(&cfile->file_info_lock);
838 if (server->ops->close_dir)
839 rc = server->ops->close_dir(xid, tcon, &cfile->fid);
840 else
841 rc = -ENOSYS;
842 cifs_dbg(FYI, "Closing uncompleted readdir with rc %d\n", rc);
843 /* not much we can do if it fails anyway, ignore rc */
844 rc = 0;
845 } else
846 spin_unlock(&cfile->file_info_lock);
847
848 buf = cfile->srch_inf.ntwrk_buf_start;
849 if (buf) {
850 cifs_dbg(FYI, "closedir free smb buf in srch struct\n");
851 cfile->srch_inf.ntwrk_buf_start = NULL;
852 if (cfile->srch_inf.smallBuf)
853 cifs_small_buf_release(buf);
854 else
855 cifs_buf_release(buf);
856 }
857
858 cifs_put_tlink(cfile->tlink);
859 kfree(file->private_data);
860 file->private_data = NULL;
861 /* BB can we lock the filestruct while this is going on? */
862 free_xid(xid);
863 return rc;
864 }
865
866 static struct cifsLockInfo *
867 cifs_lock_init(__u64 offset, __u64 length, __u8 type)
868 {
869 struct cifsLockInfo *lock =
870 kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
871 if (!lock)
872 return lock;
873 lock->offset = offset;
874 lock->length = length;
875 lock->type = type;
876 lock->pid = current->tgid;
877 INIT_LIST_HEAD(&lock->blist);
878 init_waitqueue_head(&lock->block_q);
879 return lock;
880 }
881
882 void
883 cifs_del_lock_waiters(struct cifsLockInfo *lock)
884 {
885 struct cifsLockInfo *li, *tmp;
886 list_for_each_entry_safe(li, tmp, &lock->blist, blist) {
887 list_del_init(&li->blist);
888 wake_up(&li->block_q);
889 }
890 }
891
892 #define CIFS_LOCK_OP 0
893 #define CIFS_READ_OP 1
894 #define CIFS_WRITE_OP 2
895
896 /* @rw_check : 0 - no op, 1 - read, 2 - write */
897 static bool
898 cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
899 __u64 length, __u8 type, struct cifsFileInfo *cfile,
900 struct cifsLockInfo **conf_lock, int rw_check)
901 {
902 struct cifsLockInfo *li;
903 struct cifsFileInfo *cur_cfile = fdlocks->cfile;
904 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
905
906 list_for_each_entry(li, &fdlocks->locks, llist) {
907 if (offset + length <= li->offset ||
908 offset >= li->offset + li->length)
909 continue;
910 if (rw_check != CIFS_LOCK_OP && current->tgid == li->pid &&
911 server->ops->compare_fids(cfile, cur_cfile)) {
912 /* shared lock prevents write op through the same fid */
913 if (!(li->type & server->vals->shared_lock_type) ||
914 rw_check != CIFS_WRITE_OP)
915 continue;
916 }
917 if ((type & server->vals->shared_lock_type) &&
918 ((server->ops->compare_fids(cfile, cur_cfile) &&
919 current->tgid == li->pid) || type == li->type))
920 continue;
921 if (conf_lock)
922 *conf_lock = li;
923 return true;
924 }
925 return false;
926 }
927
928 bool
929 cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
930 __u8 type, struct cifsLockInfo **conf_lock,
931 int rw_check)
932 {
933 bool rc = false;
934 struct cifs_fid_locks *cur;
935 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
936
937 list_for_each_entry(cur, &cinode->llist, llist) {
938 rc = cifs_find_fid_lock_conflict(cur, offset, length, type,
939 cfile, conf_lock, rw_check);
940 if (rc)
941 break;
942 }
943
944 return rc;
945 }
946
947 /*
948 * Check if there is another lock that prevents us to set the lock (mandatory
949 * style). If such a lock exists, update the flock structure with its
950 * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
951 * or leave it the same if we can't. Returns 0 if we don't need to request to
952 * the server or 1 otherwise.
953 */
954 static int
955 cifs_lock_test(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
956 __u8 type, struct file_lock *flock)
957 {
958 int rc = 0;
959 struct cifsLockInfo *conf_lock;
960 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
961 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
962 bool exist;
963
964 down_read(&cinode->lock_sem);
965
966 exist = cifs_find_lock_conflict(cfile, offset, length, type,
967 &conf_lock, CIFS_LOCK_OP);
968 if (exist) {
969 flock->fl_start = conf_lock->offset;
970 flock->fl_end = conf_lock->offset + conf_lock->length - 1;
971 flock->fl_pid = conf_lock->pid;
972 if (conf_lock->type & server->vals->shared_lock_type)
973 flock->fl_type = F_RDLCK;
974 else
975 flock->fl_type = F_WRLCK;
976 } else if (!cinode->can_cache_brlcks)
977 rc = 1;
978 else
979 flock->fl_type = F_UNLCK;
980
981 up_read(&cinode->lock_sem);
982 return rc;
983 }
984
985 static void
986 cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock)
987 {
988 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
989 down_write(&cinode->lock_sem);
990 list_add_tail(&lock->llist, &cfile->llist->locks);
991 up_write(&cinode->lock_sem);
992 }
993
994 /*
995 * Set the byte-range lock (mandatory style). Returns:
996 * 1) 0, if we set the lock and don't need to request to the server;
997 * 2) 1, if no locks prevent us but we need to request to the server;
998 * 3) -EACCESS, if there is a lock that prevents us and wait is false.
999 */
1000 static int
1001 cifs_lock_add_if(struct cifsFileInfo *cfile, struct cifsLockInfo *lock,
1002 bool wait)
1003 {
1004 struct cifsLockInfo *conf_lock;
1005 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1006 bool exist;
1007 int rc = 0;
1008
1009 try_again:
1010 exist = false;
1011 down_write(&cinode->lock_sem);
1012
1013 exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length,
1014 lock->type, &conf_lock, CIFS_LOCK_OP);
1015 if (!exist && cinode->can_cache_brlcks) {
1016 list_add_tail(&lock->llist, &cfile->llist->locks);
1017 up_write(&cinode->lock_sem);
1018 return rc;
1019 }
1020
1021 if (!exist)
1022 rc = 1;
1023 else if (!wait)
1024 rc = -EACCES;
1025 else {
1026 list_add_tail(&lock->blist, &conf_lock->blist);
1027 up_write(&cinode->lock_sem);
1028 rc = wait_event_interruptible(lock->block_q,
1029 (lock->blist.prev == &lock->blist) &&
1030 (lock->blist.next == &lock->blist));
1031 if (!rc)
1032 goto try_again;
1033 down_write(&cinode->lock_sem);
1034 list_del_init(&lock->blist);
1035 }
1036
1037 up_write(&cinode->lock_sem);
1038 return rc;
1039 }
1040
1041 /*
1042 * Check if there is another lock that prevents us to set the lock (posix
1043 * style). If such a lock exists, update the flock structure with its
1044 * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
1045 * or leave it the same if we can't. Returns 0 if we don't need to request to
1046 * the server or 1 otherwise.
1047 */
1048 static int
1049 cifs_posix_lock_test(struct file *file, struct file_lock *flock)
1050 {
1051 int rc = 0;
1052 struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
1053 unsigned char saved_type = flock->fl_type;
1054
1055 if ((flock->fl_flags & FL_POSIX) == 0)
1056 return 1;
1057
1058 down_read(&cinode->lock_sem);
1059 posix_test_lock(file, flock);
1060
1061 if (flock->fl_type == F_UNLCK && !cinode->can_cache_brlcks) {
1062 flock->fl_type = saved_type;
1063 rc = 1;
1064 }
1065
1066 up_read(&cinode->lock_sem);
1067 return rc;
1068 }
1069
1070 /*
1071 * Set the byte-range lock (posix style). Returns:
1072 * 1) 0, if we set the lock and don't need to request to the server;
1073 * 2) 1, if we need to request to the server;
1074 * 3) <0, if the error occurs while setting the lock.
1075 */
1076 static int
1077 cifs_posix_lock_set(struct file *file, struct file_lock *flock)
1078 {
1079 struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
1080 int rc = 1;
1081
1082 if ((flock->fl_flags & FL_POSIX) == 0)
1083 return rc;
1084
1085 try_again:
1086 down_write(&cinode->lock_sem);
1087 if (!cinode->can_cache_brlcks) {
1088 up_write(&cinode->lock_sem);
1089 return rc;
1090 }
1091
1092 rc = posix_lock_file(file, flock, NULL);
1093 up_write(&cinode->lock_sem);
1094 if (rc == FILE_LOCK_DEFERRED) {
1095 rc = wait_event_interruptible(flock->fl_wait, !flock->fl_next);
1096 if (!rc)
1097 goto try_again;
1098 posix_unblock_lock(flock);
1099 }
1100 return rc;
1101 }
1102
1103 int
1104 cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
1105 {
1106 unsigned int xid;
1107 int rc = 0, stored_rc;
1108 struct cifsLockInfo *li, *tmp;
1109 struct cifs_tcon *tcon;
1110 unsigned int num, max_num, max_buf;
1111 LOCKING_ANDX_RANGE *buf, *cur;
1112 static const int types[] = {
1113 LOCKING_ANDX_LARGE_FILES,
1114 LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES
1115 };
1116 int i;
1117
1118 xid = get_xid();
1119 tcon = tlink_tcon(cfile->tlink);
1120
1121 /*
1122 * Accessing maxBuf is racy with cifs_reconnect - need to store value
1123 * and check it for zero before using.
1124 */
1125 max_buf = tcon->ses->server->maxBuf;
1126 if (!max_buf) {
1127 free_xid(xid);
1128 return -EINVAL;
1129 }
1130
1131 max_num = (max_buf - sizeof(struct smb_hdr)) /
1132 sizeof(LOCKING_ANDX_RANGE);
1133 buf = kcalloc(max_num, sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
1134 if (!buf) {
1135 free_xid(xid);
1136 return -ENOMEM;
1137 }
1138
1139 for (i = 0; i < 2; i++) {
1140 cur = buf;
1141 num = 0;
1142 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
1143 if (li->type != types[i])
1144 continue;
1145 cur->Pid = cpu_to_le16(li->pid);
1146 cur->LengthLow = cpu_to_le32((u32)li->length);
1147 cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
1148 cur->OffsetLow = cpu_to_le32((u32)li->offset);
1149 cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
1150 if (++num == max_num) {
1151 stored_rc = cifs_lockv(xid, tcon,
1152 cfile->fid.netfid,
1153 (__u8)li->type, 0, num,
1154 buf);
1155 if (stored_rc)
1156 rc = stored_rc;
1157 cur = buf;
1158 num = 0;
1159 } else
1160 cur++;
1161 }
1162
1163 if (num) {
1164 stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
1165 (__u8)types[i], 0, num, buf);
1166 if (stored_rc)
1167 rc = stored_rc;
1168 }
1169 }
1170
1171 kfree(buf);
1172 free_xid(xid);
1173 return rc;
1174 }
1175
1176 static __u32
1177 hash_lockowner(fl_owner_t owner)
1178 {
1179 return cifs_lock_secret ^ hash32_ptr((const void *)owner);
1180 }
1181
1182 struct lock_to_push {
1183 struct list_head llist;
1184 __u64 offset;
1185 __u64 length;
1186 __u32 pid;
1187 __u16 netfid;
1188 __u8 type;
1189 };
1190
1191 static int
1192 cifs_push_posix_locks(struct cifsFileInfo *cfile)
1193 {
1194 struct inode *inode = d_inode(cfile->dentry);
1195 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1196 struct file_lock *flock;
1197 struct file_lock_context *flctx = inode->i_flctx;
1198 unsigned int count = 0, i;
1199 int rc = 0, xid, type;
1200 struct list_head locks_to_send, *el;
1201 struct lock_to_push *lck, *tmp;
1202 __u64 length;
1203
1204 xid = get_xid();
1205
1206 if (!flctx)
1207 goto out;
1208
1209 spin_lock(&flctx->flc_lock);
1210 list_for_each(el, &flctx->flc_posix) {
1211 count++;
1212 }
1213 spin_unlock(&flctx->flc_lock);
1214
1215 INIT_LIST_HEAD(&locks_to_send);
1216
1217 /*
1218 * Allocating count locks is enough because no FL_POSIX locks can be
1219 * added to the list while we are holding cinode->lock_sem that
1220 * protects locking operations of this inode.
1221 */
1222 for (i = 0; i < count; i++) {
1223 lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
1224 if (!lck) {
1225 rc = -ENOMEM;
1226 goto err_out;
1227 }
1228 list_add_tail(&lck->llist, &locks_to_send);
1229 }
1230
1231 el = locks_to_send.next;
1232 spin_lock(&flctx->flc_lock);
1233 list_for_each_entry(flock, &flctx->flc_posix, fl_list) {
1234 if (el == &locks_to_send) {
1235 /*
1236 * The list ended. We don't have enough allocated
1237 * structures - something is really wrong.
1238 */
1239 cifs_dbg(VFS, "Can't push all brlocks!\n");
1240 break;
1241 }
1242 length = 1 + flock->fl_end - flock->fl_start;
1243 if (flock->fl_type == F_RDLCK || flock->fl_type == F_SHLCK)
1244 type = CIFS_RDLCK;
1245 else
1246 type = CIFS_WRLCK;
1247 lck = list_entry(el, struct lock_to_push, llist);
1248 lck->pid = hash_lockowner(flock->fl_owner);
1249 lck->netfid = cfile->fid.netfid;
1250 lck->length = length;
1251 lck->type = type;
1252 lck->offset = flock->fl_start;
1253 }
1254 spin_unlock(&flctx->flc_lock);
1255
1256 list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
1257 int stored_rc;
1258
1259 stored_rc = CIFSSMBPosixLock(xid, tcon, lck->netfid, lck->pid,
1260 lck->offset, lck->length, NULL,
1261 lck->type, 0);
1262 if (stored_rc)
1263 rc = stored_rc;
1264 list_del(&lck->llist);
1265 kfree(lck);
1266 }
1267
1268 out:
1269 free_xid(xid);
1270 return rc;
1271 err_out:
1272 list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
1273 list_del(&lck->llist);
1274 kfree(lck);
1275 }
1276 goto out;
1277 }
1278
1279 static int
1280 cifs_push_locks(struct cifsFileInfo *cfile)
1281 {
1282 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
1283 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1284 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1285 int rc = 0;
1286
1287 /* we are going to update can_cache_brlcks here - need a write access */
1288 down_write(&cinode->lock_sem);
1289 if (!cinode->can_cache_brlcks) {
1290 up_write(&cinode->lock_sem);
1291 return rc;
1292 }
1293
1294 if (cap_unix(tcon->ses) &&
1295 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1296 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1297 rc = cifs_push_posix_locks(cfile);
1298 else
1299 rc = tcon->ses->server->ops->push_mand_locks(cfile);
1300
1301 cinode->can_cache_brlcks = false;
1302 up_write(&cinode->lock_sem);
1303 return rc;
1304 }
1305
1306 static void
1307 cifs_read_flock(struct file_lock *flock, __u32 *type, int *lock, int *unlock,
1308 bool *wait_flag, struct TCP_Server_Info *server)
1309 {
1310 if (flock->fl_flags & FL_POSIX)
1311 cifs_dbg(FYI, "Posix\n");
1312 if (flock->fl_flags & FL_FLOCK)
1313 cifs_dbg(FYI, "Flock\n");
1314 if (flock->fl_flags & FL_SLEEP) {
1315 cifs_dbg(FYI, "Blocking lock\n");
1316 *wait_flag = true;
1317 }
1318 if (flock->fl_flags & FL_ACCESS)
1319 cifs_dbg(FYI, "Process suspended by mandatory locking - not implemented yet\n");
1320 if (flock->fl_flags & FL_LEASE)
1321 cifs_dbg(FYI, "Lease on file - not implemented yet\n");
1322 if (flock->fl_flags &
1323 (~(FL_POSIX | FL_FLOCK | FL_SLEEP |
1324 FL_ACCESS | FL_LEASE | FL_CLOSE)))
1325 cifs_dbg(FYI, "Unknown lock flags 0x%x\n", flock->fl_flags);
1326
1327 *type = server->vals->large_lock_type;
1328 if (flock->fl_type == F_WRLCK) {
1329 cifs_dbg(FYI, "F_WRLCK\n");
1330 *type |= server->vals->exclusive_lock_type;
1331 *lock = 1;
1332 } else if (flock->fl_type == F_UNLCK) {
1333 cifs_dbg(FYI, "F_UNLCK\n");
1334 *type |= server->vals->unlock_lock_type;
1335 *unlock = 1;
1336 /* Check if unlock includes more than one lock range */
1337 } else if (flock->fl_type == F_RDLCK) {
1338 cifs_dbg(FYI, "F_RDLCK\n");
1339 *type |= server->vals->shared_lock_type;
1340 *lock = 1;
1341 } else if (flock->fl_type == F_EXLCK) {
1342 cifs_dbg(FYI, "F_EXLCK\n");
1343 *type |= server->vals->exclusive_lock_type;
1344 *lock = 1;
1345 } else if (flock->fl_type == F_SHLCK) {
1346 cifs_dbg(FYI, "F_SHLCK\n");
1347 *type |= server->vals->shared_lock_type;
1348 *lock = 1;
1349 } else
1350 cifs_dbg(FYI, "Unknown type of lock\n");
1351 }
1352
1353 static int
1354 cifs_getlk(struct file *file, struct file_lock *flock, __u32 type,
1355 bool wait_flag, bool posix_lck, unsigned int xid)
1356 {
1357 int rc = 0;
1358 __u64 length = 1 + flock->fl_end - flock->fl_start;
1359 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
1360 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1361 struct TCP_Server_Info *server = tcon->ses->server;
1362 __u16 netfid = cfile->fid.netfid;
1363
1364 if (posix_lck) {
1365 int posix_lock_type;
1366
1367 rc = cifs_posix_lock_test(file, flock);
1368 if (!rc)
1369 return rc;
1370
1371 if (type & server->vals->shared_lock_type)
1372 posix_lock_type = CIFS_RDLCK;
1373 else
1374 posix_lock_type = CIFS_WRLCK;
1375 rc = CIFSSMBPosixLock(xid, tcon, netfid,
1376 hash_lockowner(flock->fl_owner),
1377 flock->fl_start, length, flock,
1378 posix_lock_type, wait_flag);
1379 return rc;
1380 }
1381
1382 rc = cifs_lock_test(cfile, flock->fl_start, length, type, flock);
1383 if (!rc)
1384 return rc;
1385
1386 /* BB we could chain these into one lock request BB */
1387 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length, type,
1388 1, 0, false);
1389 if (rc == 0) {
1390 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1391 type, 0, 1, false);
1392 flock->fl_type = F_UNLCK;
1393 if (rc != 0)
1394 cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
1395 rc);
1396 return 0;
1397 }
1398
1399 if (type & server->vals->shared_lock_type) {
1400 flock->fl_type = F_WRLCK;
1401 return 0;
1402 }
1403
1404 type &= ~server->vals->exclusive_lock_type;
1405
1406 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1407 type | server->vals->shared_lock_type,
1408 1, 0, false);
1409 if (rc == 0) {
1410 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1411 type | server->vals->shared_lock_type, 0, 1, false);
1412 flock->fl_type = F_RDLCK;
1413 if (rc != 0)
1414 cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
1415 rc);
1416 } else
1417 flock->fl_type = F_WRLCK;
1418
1419 return 0;
1420 }
1421
1422 void
1423 cifs_move_llist(struct list_head *source, struct list_head *dest)
1424 {
1425 struct list_head *li, *tmp;
1426 list_for_each_safe(li, tmp, source)
1427 list_move(li, dest);
1428 }
1429
1430 void
1431 cifs_free_llist(struct list_head *llist)
1432 {
1433 struct cifsLockInfo *li, *tmp;
1434 list_for_each_entry_safe(li, tmp, llist, llist) {
1435 cifs_del_lock_waiters(li);
1436 list_del(&li->llist);
1437 kfree(li);
1438 }
1439 }
1440
1441 int
1442 cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
1443 unsigned int xid)
1444 {
1445 int rc = 0, stored_rc;
1446 static const int types[] = {
1447 LOCKING_ANDX_LARGE_FILES,
1448 LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES
1449 };
1450 unsigned int i;
1451 unsigned int max_num, num, max_buf;
1452 LOCKING_ANDX_RANGE *buf, *cur;
1453 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1454 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1455 struct cifsLockInfo *li, *tmp;
1456 __u64 length = 1 + flock->fl_end - flock->fl_start;
1457 struct list_head tmp_llist;
1458
1459 INIT_LIST_HEAD(&tmp_llist);
1460
1461 /*
1462 * Accessing maxBuf is racy with cifs_reconnect - need to store value
1463 * and check it for zero before using.
1464 */
1465 max_buf = tcon->ses->server->maxBuf;
1466 if (!max_buf)
1467 return -EINVAL;
1468
1469 max_num = (max_buf - sizeof(struct smb_hdr)) /
1470 sizeof(LOCKING_ANDX_RANGE);
1471 buf = kcalloc(max_num, sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
1472 if (!buf)
1473 return -ENOMEM;
1474
1475 down_write(&cinode->lock_sem);
1476 for (i = 0; i < 2; i++) {
1477 cur = buf;
1478 num = 0;
1479 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
1480 if (flock->fl_start > li->offset ||
1481 (flock->fl_start + length) <
1482 (li->offset + li->length))
1483 continue;
1484 if (current->tgid != li->pid)
1485 continue;
1486 if (types[i] != li->type)
1487 continue;
1488 if (cinode->can_cache_brlcks) {
1489 /*
1490 * We can cache brlock requests - simply remove
1491 * a lock from the file's list.
1492 */
1493 list_del(&li->llist);
1494 cifs_del_lock_waiters(li);
1495 kfree(li);
1496 continue;
1497 }
1498 cur->Pid = cpu_to_le16(li->pid);
1499 cur->LengthLow = cpu_to_le32((u32)li->length);
1500 cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
1501 cur->OffsetLow = cpu_to_le32((u32)li->offset);
1502 cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
1503 /*
1504 * We need to save a lock here to let us add it again to
1505 * the file's list if the unlock range request fails on
1506 * the server.
1507 */
1508 list_move(&li->llist, &tmp_llist);
1509 if (++num == max_num) {
1510 stored_rc = cifs_lockv(xid, tcon,
1511 cfile->fid.netfid,
1512 li->type, num, 0, buf);
1513 if (stored_rc) {
1514 /*
1515 * We failed on the unlock range
1516 * request - add all locks from the tmp
1517 * list to the head of the file's list.
1518 */
1519 cifs_move_llist(&tmp_llist,
1520 &cfile->llist->locks);
1521 rc = stored_rc;
1522 } else
1523 /*
1524 * The unlock range request succeed -
1525 * free the tmp list.
1526 */
1527 cifs_free_llist(&tmp_llist);
1528 cur = buf;
1529 num = 0;
1530 } else
1531 cur++;
1532 }
1533 if (num) {
1534 stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
1535 types[i], num, 0, buf);
1536 if (stored_rc) {
1537 cifs_move_llist(&tmp_llist,
1538 &cfile->llist->locks);
1539 rc = stored_rc;
1540 } else
1541 cifs_free_llist(&tmp_llist);
1542 }
1543 }
1544
1545 up_write(&cinode->lock_sem);
1546 kfree(buf);
1547 return rc;
1548 }
1549
1550 static int
1551 cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
1552 bool wait_flag, bool posix_lck, int lock, int unlock,
1553 unsigned int xid)
1554 {
1555 int rc = 0;
1556 __u64 length = 1 + flock->fl_end - flock->fl_start;
1557 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
1558 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1559 struct TCP_Server_Info *server = tcon->ses->server;
1560 struct inode *inode = d_inode(cfile->dentry);
1561
1562 if (posix_lck) {
1563 int posix_lock_type;
1564
1565 rc = cifs_posix_lock_set(file, flock);
1566 if (!rc || rc < 0)
1567 return rc;
1568
1569 if (type & server->vals->shared_lock_type)
1570 posix_lock_type = CIFS_RDLCK;
1571 else
1572 posix_lock_type = CIFS_WRLCK;
1573
1574 if (unlock == 1)
1575 posix_lock_type = CIFS_UNLCK;
1576
1577 rc = CIFSSMBPosixLock(xid, tcon, cfile->fid.netfid,
1578 hash_lockowner(flock->fl_owner),
1579 flock->fl_start, length,
1580 NULL, posix_lock_type, wait_flag);
1581 goto out;
1582 }
1583
1584 if (lock) {
1585 struct cifsLockInfo *lock;
1586
1587 lock = cifs_lock_init(flock->fl_start, length, type);
1588 if (!lock)
1589 return -ENOMEM;
1590
1591 rc = cifs_lock_add_if(cfile, lock, wait_flag);
1592 if (rc < 0) {
1593 kfree(lock);
1594 return rc;
1595 }
1596 if (!rc)
1597 goto out;
1598
1599 /*
1600 * Windows 7 server can delay breaking lease from read to None
1601 * if we set a byte-range lock on a file - break it explicitly
1602 * before sending the lock to the server to be sure the next
1603 * read won't conflict with non-overlapted locks due to
1604 * pagereading.
1605 */
1606 if (!CIFS_CACHE_WRITE(CIFS_I(inode)) &&
1607 CIFS_CACHE_READ(CIFS_I(inode))) {
1608 cifs_zap_mapping(inode);
1609 cifs_dbg(FYI, "Set no oplock for inode=%p due to mand locks\n",
1610 inode);
1611 CIFS_I(inode)->oplock = 0;
1612 }
1613
1614 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1615 type, 1, 0, wait_flag);
1616 if (rc) {
1617 kfree(lock);
1618 return rc;
1619 }
1620
1621 cifs_lock_add(cfile, lock);
1622 } else if (unlock)
1623 rc = server->ops->mand_unlock_range(cfile, flock, xid);
1624
1625 out:
1626 if (flock->fl_flags & FL_POSIX && !rc)
1627 rc = locks_lock_file_wait(file, flock);
1628 return rc;
1629 }
1630
1631 int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
1632 {
1633 int rc, xid;
1634 int lock = 0, unlock = 0;
1635 bool wait_flag = false;
1636 bool posix_lck = false;
1637 struct cifs_sb_info *cifs_sb;
1638 struct cifs_tcon *tcon;
1639 struct cifsInodeInfo *cinode;
1640 struct cifsFileInfo *cfile;
1641 __u16 netfid;
1642 __u32 type;
1643
1644 rc = -EACCES;
1645 xid = get_xid();
1646
1647 cifs_dbg(FYI, "Lock parm: 0x%x flockflags: 0x%x flocktype: 0x%x start: %lld end: %lld\n",
1648 cmd, flock->fl_flags, flock->fl_type,
1649 flock->fl_start, flock->fl_end);
1650
1651 cfile = (struct cifsFileInfo *)file->private_data;
1652 tcon = tlink_tcon(cfile->tlink);
1653
1654 cifs_read_flock(flock, &type, &lock, &unlock, &wait_flag,
1655 tcon->ses->server);
1656
1657 cifs_sb = CIFS_FILE_SB(file);
1658 netfid = cfile->fid.netfid;
1659 cinode = CIFS_I(file_inode(file));
1660
1661 if (cap_unix(tcon->ses) &&
1662 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1663 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1664 posix_lck = true;
1665 /*
1666 * BB add code here to normalize offset and length to account for
1667 * negative length which we can not accept over the wire.
1668 */
1669 if (IS_GETLK(cmd)) {
1670 rc = cifs_getlk(file, flock, type, wait_flag, posix_lck, xid);
1671 free_xid(xid);
1672 return rc;
1673 }
1674
1675 if (!lock && !unlock) {
1676 /*
1677 * if no lock or unlock then nothing to do since we do not
1678 * know what it is
1679 */
1680 free_xid(xid);
1681 return -EOPNOTSUPP;
1682 }
1683
1684 rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock,
1685 xid);
1686 free_xid(xid);
1687 return rc;
1688 }
1689
1690 /*
1691 * update the file size (if needed) after a write. Should be called with
1692 * the inode->i_lock held
1693 */
1694 void
1695 cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
1696 unsigned int bytes_written)
1697 {
1698 loff_t end_of_write = offset + bytes_written;
1699
1700 if (end_of_write > cifsi->server_eof)
1701 cifsi->server_eof = end_of_write;
1702 }
1703
1704 static ssize_t
1705 cifs_write(struct cifsFileInfo *open_file, __u32 pid, const char *write_data,
1706 size_t write_size, loff_t *offset)
1707 {
1708 int rc = 0;
1709 unsigned int bytes_written = 0;
1710 unsigned int total_written;
1711 struct cifs_sb_info *cifs_sb;
1712 struct cifs_tcon *tcon;
1713 struct TCP_Server_Info *server;
1714 unsigned int xid;
1715 struct dentry *dentry = open_file->dentry;
1716 struct cifsInodeInfo *cifsi = CIFS_I(d_inode(dentry));
1717 struct cifs_io_parms io_parms;
1718
1719 cifs_sb = CIFS_SB(dentry->d_sb);
1720
1721 cifs_dbg(FYI, "write %zd bytes to offset %lld of %pd\n",
1722 write_size, *offset, dentry);
1723
1724 tcon = tlink_tcon(open_file->tlink);
1725 server = tcon->ses->server;
1726
1727 if (!server->ops->sync_write)
1728 return -ENOSYS;
1729
1730 xid = get_xid();
1731
1732 for (total_written = 0; write_size > total_written;
1733 total_written += bytes_written) {
1734 rc = -EAGAIN;
1735 while (rc == -EAGAIN) {
1736 struct kvec iov[2];
1737 unsigned int len;
1738
1739 if (open_file->invalidHandle) {
1740 /* we could deadlock if we called
1741 filemap_fdatawait from here so tell
1742 reopen_file not to flush data to
1743 server now */
1744 rc = cifs_reopen_file(open_file, false);
1745 if (rc != 0)
1746 break;
1747 }
1748
1749 len = min(server->ops->wp_retry_size(d_inode(dentry)),
1750 (unsigned int)write_size - total_written);
1751 /* iov[0] is reserved for smb header */
1752 iov[1].iov_base = (char *)write_data + total_written;
1753 iov[1].iov_len = len;
1754 io_parms.pid = pid;
1755 io_parms.tcon = tcon;
1756 io_parms.offset = *offset;
1757 io_parms.length = len;
1758 rc = server->ops->sync_write(xid, &open_file->fid,
1759 &io_parms, &bytes_written, iov, 1);
1760 }
1761 if (rc || (bytes_written == 0)) {
1762 if (total_written)
1763 break;
1764 else {
1765 free_xid(xid);
1766 return rc;
1767 }
1768 } else {
1769 spin_lock(&d_inode(dentry)->i_lock);
1770 cifs_update_eof(cifsi, *offset, bytes_written);
1771 spin_unlock(&d_inode(dentry)->i_lock);
1772 *offset += bytes_written;
1773 }
1774 }
1775
1776 cifs_stats_bytes_written(tcon, total_written);
1777
1778 if (total_written > 0) {
1779 spin_lock(&d_inode(dentry)->i_lock);
1780 if (*offset > d_inode(dentry)->i_size)
1781 i_size_write(d_inode(dentry), *offset);
1782 spin_unlock(&d_inode(dentry)->i_lock);
1783 }
1784 mark_inode_dirty_sync(d_inode(dentry));
1785 free_xid(xid);
1786 return total_written;
1787 }
1788
1789 struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
1790 bool fsuid_only)
1791 {
1792 struct cifsFileInfo *open_file = NULL;
1793 struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
1794 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
1795
1796 /* only filter by fsuid on multiuser mounts */
1797 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
1798 fsuid_only = false;
1799
1800 spin_lock(&tcon->open_file_lock);
1801 /* we could simply get the first_list_entry since write-only entries
1802 are always at the end of the list but since the first entry might
1803 have a close pending, we go through the whole list */
1804 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1805 if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
1806 continue;
1807 if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
1808 if (!open_file->invalidHandle) {
1809 /* found a good file */
1810 /* lock it so it will not be closed on us */
1811 cifsFileInfo_get(open_file);
1812 spin_unlock(&tcon->open_file_lock);
1813 return open_file;
1814 } /* else might as well continue, and look for
1815 another, or simply have the caller reopen it
1816 again rather than trying to fix this handle */
1817 } else /* write only file */
1818 break; /* write only files are last so must be done */
1819 }
1820 spin_unlock(&tcon->open_file_lock);
1821 return NULL;
1822 }
1823
1824 struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
1825 bool fsuid_only)
1826 {
1827 struct cifsFileInfo *open_file, *inv_file = NULL;
1828 struct cifs_sb_info *cifs_sb;
1829 struct cifs_tcon *tcon;
1830 bool any_available = false;
1831 int rc;
1832 unsigned int refind = 0;
1833
1834 /* Having a null inode here (because mapping->host was set to zero by
1835 the VFS or MM) should not happen but we had reports of on oops (due to
1836 it being zero) during stress testcases so we need to check for it */
1837
1838 if (cifs_inode == NULL) {
1839 cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");
1840 dump_stack();
1841 return NULL;
1842 }
1843
1844 cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
1845 tcon = cifs_sb_master_tcon(cifs_sb);
1846
1847 /* only filter by fsuid on multiuser mounts */
1848 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
1849 fsuid_only = false;
1850
1851 spin_lock(&tcon->open_file_lock);
1852 refind_writable:
1853 if (refind > MAX_REOPEN_ATT) {
1854 spin_unlock(&tcon->open_file_lock);
1855 return NULL;
1856 }
1857 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1858 if (!any_available && open_file->pid != current->tgid)
1859 continue;
1860 if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
1861 continue;
1862 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
1863 if (!open_file->invalidHandle) {
1864 /* found a good writable file */
1865 cifsFileInfo_get(open_file);
1866 spin_unlock(&tcon->open_file_lock);
1867 return open_file;
1868 } else {
1869 if (!inv_file)
1870 inv_file = open_file;
1871 }
1872 }
1873 }
1874 /* couldn't find useable FH with same pid, try any available */
1875 if (!any_available) {
1876 any_available = true;
1877 goto refind_writable;
1878 }
1879
1880 if (inv_file) {
1881 any_available = false;
1882 cifsFileInfo_get(inv_file);
1883 }
1884
1885 spin_unlock(&tcon->open_file_lock);
1886
1887 if (inv_file) {
1888 rc = cifs_reopen_file(inv_file, false);
1889 if (!rc)
1890 return inv_file;
1891 else {
1892 spin_lock(&tcon->open_file_lock);
1893 list_move_tail(&inv_file->flist,
1894 &cifs_inode->openFileList);
1895 spin_unlock(&tcon->open_file_lock);
1896 cifsFileInfo_put(inv_file);
1897 ++refind;
1898 inv_file = NULL;
1899 spin_lock(&tcon->open_file_lock);
1900 goto refind_writable;
1901 }
1902 }
1903
1904 return NULL;
1905 }
1906
1907 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
1908 {
1909 struct address_space *mapping = page->mapping;
1910 loff_t offset = (loff_t)page->index << PAGE_SHIFT;
1911 char *write_data;
1912 int rc = -EFAULT;
1913 int bytes_written = 0;
1914 struct inode *inode;
1915 struct cifsFileInfo *open_file;
1916
1917 if (!mapping || !mapping->host)
1918 return -EFAULT;
1919
1920 inode = page->mapping->host;
1921
1922 offset += (loff_t)from;
1923 write_data = kmap(page);
1924 write_data += from;
1925
1926 if ((to > PAGE_SIZE) || (from > to)) {
1927 kunmap(page);
1928 return -EIO;
1929 }
1930
1931 /* racing with truncate? */
1932 if (offset > mapping->host->i_size) {
1933 kunmap(page);
1934 return 0; /* don't care */
1935 }
1936
1937 /* check to make sure that we are not extending the file */
1938 if (mapping->host->i_size - offset < (loff_t)to)
1939 to = (unsigned)(mapping->host->i_size - offset);
1940
1941 open_file = find_writable_file(CIFS_I(mapping->host), false);
1942 if (open_file) {
1943 bytes_written = cifs_write(open_file, open_file->pid,
1944 write_data, to - from, &offset);
1945 cifsFileInfo_put(open_file);
1946 /* Does mm or vfs already set times? */
1947 inode->i_atime = inode->i_mtime = current_time(inode);
1948 if ((bytes_written > 0) && (offset))
1949 rc = 0;
1950 else if (bytes_written < 0)
1951 rc = bytes_written;
1952 } else {
1953 cifs_dbg(FYI, "No writeable filehandles for inode\n");
1954 rc = -EIO;
1955 }
1956
1957 kunmap(page);
1958 return rc;
1959 }
1960
1961 static struct cifs_writedata *
1962 wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
1963 pgoff_t end, pgoff_t *index,
1964 unsigned int *found_pages)
1965 {
1966 struct cifs_writedata *wdata;
1967
1968 wdata = cifs_writedata_alloc((unsigned int)tofind,
1969 cifs_writev_complete);
1970 if (!wdata)
1971 return NULL;
1972
1973 *found_pages = find_get_pages_range_tag(mapping, index, end,
1974 PAGECACHE_TAG_DIRTY, tofind, wdata->pages);
1975 return wdata;
1976 }
1977
1978 static unsigned int
1979 wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
1980 struct address_space *mapping,
1981 struct writeback_control *wbc,
1982 pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
1983 {
1984 unsigned int nr_pages = 0, i;
1985 struct page *page;
1986
1987 for (i = 0; i < found_pages; i++) {
1988 page = wdata->pages[i];
1989 /*
1990 * At this point we hold neither mapping->tree_lock nor
1991 * lock on the page itself: the page may be truncated or
1992 * invalidated (changing page->mapping to NULL), or even
1993 * swizzled back from swapper_space to tmpfs file
1994 * mapping
1995 */
1996
1997 if (nr_pages == 0)
1998 lock_page(page);
1999 else if (!trylock_page(page))
2000 break;
2001
2002 if (unlikely(page->mapping != mapping)) {
2003 unlock_page(page);
2004 break;
2005 }
2006
2007 if (!wbc->range_cyclic && page->index > end) {
2008 *done = true;
2009 unlock_page(page);
2010 break;
2011 }
2012
2013 if (*next && (page->index != *next)) {
2014 /* Not next consecutive page */
2015 unlock_page(page);
2016 break;
2017 }
2018
2019 if (wbc->sync_mode != WB_SYNC_NONE)
2020 wait_on_page_writeback(page);
2021
2022 if (PageWriteback(page) ||
2023 !clear_page_dirty_for_io(page)) {
2024 unlock_page(page);
2025 break;
2026 }
2027
2028 /*
2029 * This actually clears the dirty bit in the radix tree.
2030 * See cifs_writepage() for more commentary.
2031 */
2032 set_page_writeback(page);
2033 if (page_offset(page) >= i_size_read(mapping->host)) {
2034 *done = true;
2035 unlock_page(page);
2036 end_page_writeback(page);
2037 break;
2038 }
2039
2040 wdata->pages[i] = page;
2041 *next = page->index + 1;
2042 ++nr_pages;
2043 }
2044
2045 /* reset index to refind any pages skipped */
2046 if (nr_pages == 0)
2047 *index = wdata->pages[0]->index + 1;
2048
2049 /* put any pages we aren't going to use */
2050 for (i = nr_pages; i < found_pages; i++) {
2051 put_page(wdata->pages[i]);
2052 wdata->pages[i] = NULL;
2053 }
2054
2055 return nr_pages;
2056 }
2057
2058 static int
2059 wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
2060 struct address_space *mapping, struct writeback_control *wbc)
2061 {
2062 int rc = 0;
2063 struct TCP_Server_Info *server;
2064 unsigned int i;
2065
2066 wdata->sync_mode = wbc->sync_mode;
2067 wdata->nr_pages = nr_pages;
2068 wdata->offset = page_offset(wdata->pages[0]);
2069 wdata->pagesz = PAGE_SIZE;
2070 wdata->tailsz = min(i_size_read(mapping->host) -
2071 page_offset(wdata->pages[nr_pages - 1]),
2072 (loff_t)PAGE_SIZE);
2073 wdata->bytes = ((nr_pages - 1) * PAGE_SIZE) + wdata->tailsz;
2074
2075 if (wdata->cfile != NULL)
2076 cifsFileInfo_put(wdata->cfile);
2077 wdata->cfile = find_writable_file(CIFS_I(mapping->host), false);
2078 if (!wdata->cfile) {
2079 cifs_dbg(VFS, "No writable handles for inode\n");
2080 rc = -EBADF;
2081 } else {
2082 wdata->pid = wdata->cfile->pid;
2083 server = tlink_tcon(wdata->cfile->tlink)->ses->server;
2084 rc = server->ops->async_writev(wdata, cifs_writedata_release);
2085 }
2086
2087 for (i = 0; i < nr_pages; ++i)
2088 unlock_page(wdata->pages[i]);
2089
2090 return rc;
2091 }
2092
2093 static int cifs_writepages(struct address_space *mapping,
2094 struct writeback_control *wbc)
2095 {
2096 struct cifs_sb_info *cifs_sb = CIFS_SB(mapping->host->i_sb);
2097 struct TCP_Server_Info *server;
2098 bool done = false, scanned = false, range_whole = false;
2099 pgoff_t end, index;
2100 struct cifs_writedata *wdata;
2101 int rc = 0;
2102
2103 /*
2104 * If wsize is smaller than the page cache size, default to writing
2105 * one page at a time via cifs_writepage
2106 */
2107 if (cifs_sb->wsize < PAGE_SIZE)
2108 return generic_writepages(mapping, wbc);
2109
2110 if (wbc->range_cyclic) {
2111 index = mapping->writeback_index; /* Start from prev offset */
2112 end = -1;
2113 } else {
2114 index = wbc->range_start >> PAGE_SHIFT;
2115 end = wbc->range_end >> PAGE_SHIFT;
2116 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
2117 range_whole = true;
2118 scanned = true;
2119 }
2120 server = cifs_sb_master_tcon(cifs_sb)->ses->server;
2121 retry:
2122 while (!done && index <= end) {
2123 unsigned int i, nr_pages, found_pages, wsize, credits;
2124 pgoff_t next = 0, tofind, saved_index = index;
2125
2126 rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,
2127 &wsize, &credits);
2128 if (rc)
2129 break;
2130
2131 tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1;
2132
2133 wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
2134 &found_pages);
2135 if (!wdata) {
2136 rc = -ENOMEM;
2137 add_credits_and_wake_if(server, credits, 0);
2138 break;
2139 }
2140
2141 if (found_pages == 0) {
2142 kref_put(&wdata->refcount, cifs_writedata_release);
2143 add_credits_and_wake_if(server, credits, 0);
2144 break;
2145 }
2146
2147 nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
2148 end, &index, &next, &done);
2149
2150 /* nothing to write? */
2151 if (nr_pages == 0) {
2152 kref_put(&wdata->refcount, cifs_writedata_release);
2153 add_credits_and_wake_if(server, credits, 0);
2154 continue;
2155 }
2156
2157 wdata->credits = credits;
2158
2159 rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
2160
2161 /* send failure -- clean up the mess */
2162 if (rc != 0) {
2163 add_credits_and_wake_if(server, wdata->credits, 0);
2164 for (i = 0; i < nr_pages; ++i) {
2165 if (rc == -EAGAIN)
2166 redirty_page_for_writepage(wbc,
2167 wdata->pages[i]);
2168 else
2169 SetPageError(wdata->pages[i]);
2170 end_page_writeback(wdata->pages[i]);
2171 put_page(wdata->pages[i]);
2172 }
2173 if (rc != -EAGAIN)
2174 mapping_set_error(mapping, rc);
2175 }
2176 kref_put(&wdata->refcount, cifs_writedata_release);
2177
2178 if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) {
2179 index = saved_index;
2180 continue;
2181 }
2182
2183 wbc->nr_to_write -= nr_pages;
2184 if (wbc->nr_to_write <= 0)
2185 done = true;
2186
2187 index = next;
2188 }
2189
2190 if (!scanned && !done) {
2191 /*
2192 * We hit the last page and there is more work to be done: wrap
2193 * back to the start of the file
2194 */
2195 scanned = true;
2196 index = 0;
2197 goto retry;
2198 }
2199
2200 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
2201 mapping->writeback_index = index;
2202
2203 return rc;
2204 }
2205
2206 static int
2207 cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
2208 {
2209 int rc;
2210 unsigned int xid;
2211
2212 xid = get_xid();
2213 /* BB add check for wbc flags */
2214 get_page(page);
2215 if (!PageUptodate(page))
2216 cifs_dbg(FYI, "ppw - page not up to date\n");
2217
2218 /*
2219 * Set the "writeback" flag, and clear "dirty" in the radix tree.
2220 *
2221 * A writepage() implementation always needs to do either this,
2222 * or re-dirty the page with "redirty_page_for_writepage()" in
2223 * the case of a failure.
2224 *
2225 * Just unlocking the page will cause the radix tree tag-bits
2226 * to fail to update with the state of the page correctly.
2227 */
2228 set_page_writeback(page);
2229 retry_write:
2230 rc = cifs_partialpagewrite(page, 0, PAGE_SIZE);
2231 if (rc == -EAGAIN) {
2232 if (wbc->sync_mode == WB_SYNC_ALL)
2233 goto retry_write;
2234 redirty_page_for_writepage(wbc, page);
2235 } else if (rc != 0) {
2236 SetPageError(page);
2237 mapping_set_error(page->mapping, rc);
2238 } else {
2239 SetPageUptodate(page);
2240 }
2241 end_page_writeback(page);
2242 put_page(page);
2243 free_xid(xid);
2244 return rc;
2245 }
2246
2247 static int cifs_writepage(struct page *page, struct writeback_control *wbc)
2248 {
2249 int rc = cifs_writepage_locked(page, wbc);
2250 unlock_page(page);
2251 return rc;
2252 }
2253
2254 static int cifs_write_end(struct file *file, struct address_space *mapping,
2255 loff_t pos, unsigned len, unsigned copied,
2256 struct page *page, void *fsdata)
2257 {
2258 int rc;
2259 struct inode *inode = mapping->host;
2260 struct cifsFileInfo *cfile = file->private_data;
2261 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
2262 __u32 pid;
2263
2264 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2265 pid = cfile->pid;
2266 else
2267 pid = current->tgid;
2268
2269 cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
2270 page, pos, copied);
2271
2272 if (PageChecked(page)) {
2273 if (copied == len)
2274 SetPageUptodate(page);
2275 ClearPageChecked(page);
2276 } else if (!PageUptodate(page) && copied == PAGE_SIZE)
2277 SetPageUptodate(page);
2278
2279 if (!PageUptodate(page)) {
2280 char *page_data;
2281 unsigned offset = pos & (PAGE_SIZE - 1);
2282 unsigned int xid;
2283
2284 xid = get_xid();
2285 /* this is probably better than directly calling
2286 partialpage_write since in this function the file handle is
2287 known which we might as well leverage */
2288 /* BB check if anything else missing out of ppw
2289 such as updating last write time */
2290 page_data = kmap(page);
2291 rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
2292 /* if (rc < 0) should we set writebehind rc? */
2293 kunmap(page);
2294
2295 free_xid(xid);
2296 } else {
2297 rc = copied;
2298 pos += copied;
2299 set_page_dirty(page);
2300 }
2301
2302 if (rc > 0) {
2303 spin_lock(&inode->i_lock);
2304 if (pos > inode->i_size)
2305 i_size_write(inode, pos);
2306 spin_unlock(&inode->i_lock);
2307 }
2308
2309 unlock_page(page);
2310 put_page(page);
2311
2312 return rc;
2313 }
2314
2315 int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
2316 int datasync)
2317 {
2318 unsigned int xid;
2319 int rc = 0;
2320 struct cifs_tcon *tcon;
2321 struct TCP_Server_Info *server;
2322 struct cifsFileInfo *smbfile = file->private_data;
2323 struct inode *inode = file_inode(file);
2324 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2325
2326 rc = file_write_and_wait_range(file, start, end);
2327 if (rc)
2328 return rc;
2329 inode_lock(inode);
2330
2331 xid = get_xid();
2332
2333 cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
2334 file, datasync);
2335
2336 if (!CIFS_CACHE_READ(CIFS_I(inode))) {
2337 rc = cifs_zap_mapping(inode);
2338 if (rc) {
2339 cifs_dbg(FYI, "rc: %d during invalidate phase\n", rc);
2340 rc = 0; /* don't care about it in fsync */
2341 }
2342 }
2343
2344 tcon = tlink_tcon(smbfile->tlink);
2345 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
2346 server = tcon->ses->server;
2347 if (server->ops->flush)
2348 rc = server->ops->flush(xid, tcon, &smbfile->fid);
2349 else
2350 rc = -ENOSYS;
2351 }
2352
2353 free_xid(xid);
2354 inode_unlock(inode);
2355 return rc;
2356 }
2357
2358 int cifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2359 {
2360 unsigned int xid;
2361 int rc = 0;
2362 struct cifs_tcon *tcon;
2363 struct TCP_Server_Info *server;
2364 struct cifsFileInfo *smbfile = file->private_data;
2365 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
2366 struct inode *inode = file->f_mapping->host;
2367
2368 rc = file_write_and_wait_range(file, start, end);
2369 if (rc)
2370 return rc;
2371 inode_lock(inode);
2372
2373 xid = get_xid();
2374
2375 cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
2376 file, datasync);
2377
2378 tcon = tlink_tcon(smbfile->tlink);
2379 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
2380 server = tcon->ses->server;
2381 if (server->ops->flush)
2382 rc = server->ops->flush(xid, tcon, &smbfile->fid);
2383 else
2384 rc = -ENOSYS;
2385 }
2386
2387 free_xid(xid);
2388 inode_unlock(inode);
2389 return rc;
2390 }
2391
2392 /*
2393 * As file closes, flush all cached write data for this inode checking
2394 * for write behind errors.
2395 */
2396 int cifs_flush(struct file *file, fl_owner_t id)
2397 {
2398 struct inode *inode = file_inode(file);
2399 int rc = 0;
2400
2401 if (file->f_mode & FMODE_WRITE)
2402 rc = filemap_write_and_wait(inode->i_mapping);
2403
2404 cifs_dbg(FYI, "Flush inode %p file %p rc %d\n", inode, file, rc);
2405
2406 return rc;
2407 }
2408
2409 static int
2410 cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
2411 {
2412 int rc = 0;
2413 unsigned long i;
2414
2415 for (i = 0; i < num_pages; i++) {
2416 pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
2417 if (!pages[i]) {
2418 /*
2419 * save number of pages we have already allocated and
2420 * return with ENOMEM error
2421 */
2422 num_pages = i;
2423 rc = -ENOMEM;
2424 break;
2425 }
2426 }
2427
2428 if (rc) {
2429 for (i = 0; i < num_pages; i++)
2430 put_page(pages[i]);
2431 }
2432 return rc;
2433 }
2434
2435 static inline
2436 size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
2437 {
2438 size_t num_pages;
2439 size_t clen;
2440
2441 clen = min_t(const size_t, len, wsize);
2442 num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
2443
2444 if (cur_len)
2445 *cur_len = clen;
2446
2447 return num_pages;
2448 }
2449
2450 static void
2451 cifs_uncached_writedata_release(struct kref *refcount)
2452 {
2453 int i;
2454 struct cifs_writedata *wdata = container_of(refcount,
2455 struct cifs_writedata, refcount);
2456
2457 kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
2458 for (i = 0; i < wdata->nr_pages; i++)
2459 put_page(wdata->pages[i]);
2460 cifs_writedata_release(refcount);
2461 }
2462
2463 static void collect_uncached_write_data(struct cifs_aio_ctx *ctx);
2464
2465 static void
2466 cifs_uncached_writev_complete(struct work_struct *work)
2467 {
2468 struct cifs_writedata *wdata = container_of(work,
2469 struct cifs_writedata, work);
2470 struct inode *inode = d_inode(wdata->cfile->dentry);
2471 struct cifsInodeInfo *cifsi = CIFS_I(inode);
2472
2473 spin_lock(&inode->i_lock);
2474 cifs_update_eof(cifsi, wdata->offset, wdata->bytes);
2475 if (cifsi->server_eof > inode->i_size)
2476 i_size_write(inode, cifsi->server_eof);
2477 spin_unlock(&inode->i_lock);
2478
2479 complete(&wdata->done);
2480 collect_uncached_write_data(wdata->ctx);
2481 /* the below call can possibly free the last ref to aio ctx */
2482 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
2483 }
2484
2485 static int
2486 wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
2487 size_t *len, unsigned long *num_pages)
2488 {
2489 size_t save_len, copied, bytes, cur_len = *len;
2490 unsigned long i, nr_pages = *num_pages;
2491
2492 save_len = cur_len;
2493 for (i = 0; i < nr_pages; i++) {
2494 bytes = min_t(const size_t, cur_len, PAGE_SIZE);
2495 copied = copy_page_from_iter(wdata->pages[i], 0, bytes, from);
2496 cur_len -= copied;
2497 /*
2498 * If we didn't copy as much as we expected, then that
2499 * may mean we trod into an unmapped area. Stop copying
2500 * at that point. On the next pass through the big
2501 * loop, we'll likely end up getting a zero-length
2502 * write and bailing out of it.
2503 */
2504 if (copied < bytes)
2505 break;
2506 }
2507 cur_len = save_len - cur_len;
2508 *len = cur_len;
2509
2510 /*
2511 * If we have no data to send, then that probably means that
2512 * the copy above failed altogether. That's most likely because
2513 * the address in the iovec was bogus. Return -EFAULT and let
2514 * the caller free anything we allocated and bail out.
2515 */
2516 if (!cur_len)
2517 return -EFAULT;
2518
2519 /*
2520 * i + 1 now represents the number of pages we actually used in
2521 * the copy phase above.
2522 */
2523 *num_pages = i + 1;
2524 return 0;
2525 }
2526
2527 static int
2528 cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
2529 struct cifsFileInfo *open_file,
2530 struct cifs_sb_info *cifs_sb, struct list_head *wdata_list,
2531 struct cifs_aio_ctx *ctx)
2532 {
2533 int rc = 0;
2534 size_t cur_len;
2535 unsigned long nr_pages, num_pages, i;
2536 struct cifs_writedata *wdata;
2537 struct iov_iter saved_from = *from;
2538 loff_t saved_offset = offset;
2539 pid_t pid;
2540 struct TCP_Server_Info *server;
2541
2542 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2543 pid = open_file->pid;
2544 else
2545 pid = current->tgid;
2546
2547 server = tlink_tcon(open_file->tlink)->ses->server;
2548
2549 do {
2550 unsigned int wsize, credits;
2551
2552 rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,
2553 &wsize, &credits);
2554 if (rc)
2555 break;
2556
2557 nr_pages = get_numpages(wsize, len, &cur_len);
2558 wdata = cifs_writedata_alloc(nr_pages,
2559 cifs_uncached_writev_complete);
2560 if (!wdata) {
2561 rc = -ENOMEM;
2562 add_credits_and_wake_if(server, credits, 0);
2563 break;
2564 }
2565
2566 rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
2567 if (rc) {
2568 kfree(wdata);
2569 add_credits_and_wake_if(server, credits, 0);
2570 break;
2571 }
2572
2573 num_pages = nr_pages;
2574 rc = wdata_fill_from_iovec(wdata, from, &cur_len, &num_pages);
2575 if (rc) {
2576 for (i = 0; i < nr_pages; i++)
2577 put_page(wdata->pages[i]);
2578 kfree(wdata);
2579 add_credits_and_wake_if(server, credits, 0);
2580 break;
2581 }
2582
2583 /*
2584 * Bring nr_pages down to the number of pages we actually used,
2585 * and free any pages that we didn't use.
2586 */
2587 for ( ; nr_pages > num_pages; nr_pages--)
2588 put_page(wdata->pages[nr_pages - 1]);
2589
2590 wdata->sync_mode = WB_SYNC_ALL;
2591 wdata->nr_pages = nr_pages;
2592 wdata->offset = (__u64)offset;
2593 wdata->cfile = cifsFileInfo_get(open_file);
2594 wdata->pid = pid;
2595 wdata->bytes = cur_len;
2596 wdata->pagesz = PAGE_SIZE;
2597 wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
2598 wdata->credits = credits;
2599 wdata->ctx = ctx;
2600 kref_get(&ctx->refcount);
2601
2602 if (!wdata->cfile->invalidHandle ||
2603 !(rc = cifs_reopen_file(wdata->cfile, false)))
2604 rc = server->ops->async_writev(wdata,
2605 cifs_uncached_writedata_release);
2606 if (rc) {
2607 add_credits_and_wake_if(server, wdata->credits, 0);
2608 kref_put(&wdata->refcount,
2609 cifs_uncached_writedata_release);
2610 if (rc == -EAGAIN) {
2611 *from = saved_from;
2612 iov_iter_advance(from, offset - saved_offset);
2613 continue;
2614 }
2615 break;
2616 }
2617
2618 list_add_tail(&wdata->list, wdata_list);
2619 offset += cur_len;
2620 len -= cur_len;
2621 } while (len > 0);
2622
2623 return rc;
2624 }
2625
2626 static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
2627 {
2628 struct cifs_writedata *wdata, *tmp;
2629 struct cifs_tcon *tcon;
2630 struct cifs_sb_info *cifs_sb;
2631 struct dentry *dentry = ctx->cfile->dentry;
2632 unsigned int i;
2633 int rc;
2634
2635 tcon = tlink_tcon(ctx->cfile->tlink);
2636 cifs_sb = CIFS_SB(dentry->d_sb);
2637
2638 mutex_lock(&ctx->aio_mutex);
2639
2640 if (list_empty(&ctx->list)) {
2641 mutex_unlock(&ctx->aio_mutex);
2642 return;
2643 }
2644
2645 rc = ctx->rc;
2646 /*
2647 * Wait for and collect replies for any successful sends in order of
2648 * increasing offset. Once an error is hit, then return without waiting
2649 * for any more replies.
2650 */
2651 restart_loop:
2652 list_for_each_entry_safe(wdata, tmp, &ctx->list, list) {
2653 if (!rc) {
2654 if (!try_wait_for_completion(&wdata->done)) {
2655 mutex_unlock(&ctx->aio_mutex);
2656 return;
2657 }
2658
2659 if (wdata->result)
2660 rc = wdata->result;
2661 else
2662 ctx->total_len += wdata->bytes;
2663
2664 /* resend call if it's a retryable error */
2665 if (rc == -EAGAIN) {
2666 struct list_head tmp_list;
2667 struct iov_iter tmp_from = ctx->iter;
2668
2669 INIT_LIST_HEAD(&tmp_list);
2670 list_del_init(&wdata->list);
2671
2672 iov_iter_advance(&tmp_from,
2673 wdata->offset - ctx->pos);
2674
2675 rc = cifs_write_from_iter(wdata->offset,
2676 wdata->bytes, &tmp_from,
2677 ctx->cfile, cifs_sb, &tmp_list,
2678 ctx);
2679
2680 list_splice(&tmp_list, &ctx->list);
2681
2682 kref_put(&wdata->refcount,
2683 cifs_uncached_writedata_release);
2684 goto restart_loop;
2685 }
2686 }
2687 list_del_init(&wdata->list);
2688 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
2689 }
2690
2691 for (i = 0; i < ctx->npages; i++)
2692 put_page(ctx->bv[i].bv_page);
2693
2694 cifs_stats_bytes_written(tcon, ctx->total_len);
2695 set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(dentry->d_inode)->flags);
2696
2697 ctx->rc = (rc == 0) ? ctx->total_len : rc;
2698
2699 mutex_unlock(&ctx->aio_mutex);
2700
2701 if (ctx->iocb && ctx->iocb->ki_complete)
2702 ctx->iocb->ki_complete(ctx->iocb, ctx->rc, 0);
2703 else
2704 complete(&ctx->done);
2705 }
2706
2707 ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
2708 {
2709 struct file *file = iocb->ki_filp;
2710 ssize_t total_written = 0;
2711 struct cifsFileInfo *cfile;
2712 struct cifs_tcon *tcon;
2713 struct cifs_sb_info *cifs_sb;
2714 struct cifs_aio_ctx *ctx;
2715 struct iov_iter saved_from = *from;
2716 int rc;
2717
2718 /*
2719 * BB - optimize the way when signing is disabled. We can drop this
2720 * extra memory-to-memory copying and use iovec buffers for constructing
2721 * write request.
2722 */
2723
2724 rc = generic_write_checks(iocb, from);
2725 if (rc <= 0)
2726 return rc;
2727
2728 cifs_sb = CIFS_FILE_SB(file);
2729 cfile = file->private_data;
2730 tcon = tlink_tcon(cfile->tlink);
2731
2732 if (!tcon->ses->server->ops->async_writev)
2733 return -ENOSYS;
2734
2735 ctx = cifs_aio_ctx_alloc();
2736 if (!ctx)
2737 return -ENOMEM;
2738
2739 ctx->cfile = cifsFileInfo_get(cfile);
2740
2741 if (!is_sync_kiocb(iocb))
2742 ctx->iocb = iocb;
2743
2744 ctx->pos = iocb->ki_pos;
2745
2746 rc = setup_aio_ctx_iter(ctx, from, WRITE);
2747 if (rc) {
2748 kref_put(&ctx->refcount, cifs_aio_ctx_release);
2749 return rc;
2750 }
2751
2752 /* grab a lock here due to read response handlers can access ctx */
2753 mutex_lock(&ctx->aio_mutex);
2754
2755 rc = cifs_write_from_iter(iocb->ki_pos, ctx->len, &saved_from,
2756 cfile, cifs_sb, &ctx->list, ctx);
2757
2758 /*
2759 * If at least one write was successfully sent, then discard any rc
2760 * value from the later writes. If the other write succeeds, then
2761 * we'll end up returning whatever was written. If it fails, then
2762 * we'll get a new rc value from that.
2763 */
2764 if (!list_empty(&ctx->list))
2765 rc = 0;
2766
2767 mutex_unlock(&ctx->aio_mutex);
2768
2769 if (rc) {
2770 kref_put(&ctx->refcount, cifs_aio_ctx_release);
2771 return rc;
2772 }
2773
2774 if (!is_sync_kiocb(iocb)) {
2775 kref_put(&ctx->refcount, cifs_aio_ctx_release);
2776 return -EIOCBQUEUED;
2777 }
2778
2779 rc = wait_for_completion_killable(&ctx->done);
2780 if (rc) {
2781 mutex_lock(&ctx->aio_mutex);
2782 ctx->rc = rc = -EINTR;
2783 total_written = ctx->total_len;
2784 mutex_unlock(&ctx->aio_mutex);
2785 } else {
2786 rc = ctx->rc;
2787 total_written = ctx->total_len;
2788 }
2789
2790 kref_put(&ctx->refcount, cifs_aio_ctx_release);
2791
2792 if (unlikely(!total_written))
2793 return rc;
2794
2795 iocb->ki_pos += total_written;
2796 return total_written;
2797 }
2798
2799 static ssize_t
2800 cifs_writev(struct kiocb *iocb, struct iov_iter *from)
2801 {
2802 struct file *file = iocb->ki_filp;
2803 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
2804 struct inode *inode = file->f_mapping->host;
2805 struct cifsInodeInfo *cinode = CIFS_I(inode);
2806 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
2807 ssize_t rc;
2808
2809 inode_lock(inode);
2810 /*
2811 * We need to hold the sem to be sure nobody modifies lock list
2812 * with a brlock that prevents writing.
2813 */
2814 down_read(&cinode->lock_sem);
2815
2816 rc = generic_write_checks(iocb, from);
2817 if (rc <= 0)
2818 goto out;
2819
2820 if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(from),
2821 server->vals->exclusive_lock_type, NULL,
2822 CIFS_WRITE_OP))
2823 rc = __generic_file_write_iter(iocb, from);
2824 else
2825 rc = -EACCES;
2826 out:
2827 up_read(&cinode->lock_sem);
2828 inode_unlock(inode);
2829
2830 if (rc > 0)
2831 rc = generic_write_sync(iocb, rc);
2832 return rc;
2833 }
2834
2835 ssize_t
2836 cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
2837 {
2838 struct inode *inode = file_inode(iocb->ki_filp);
2839 struct cifsInodeInfo *cinode = CIFS_I(inode);
2840 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2841 struct cifsFileInfo *cfile = (struct cifsFileInfo *)
2842 iocb->ki_filp->private_data;
2843 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
2844 ssize_t written;
2845
2846 written = cifs_get_writer(cinode);
2847 if (written)
2848 return written;
2849
2850 if (CIFS_CACHE_WRITE(cinode)) {
2851 if (cap_unix(tcon->ses) &&
2852 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
2853 && ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
2854 written = generic_file_write_iter(iocb, from);
2855 goto out;
2856 }
2857 written = cifs_writev(iocb, from);
2858 goto out;
2859 }
2860 /*
2861 * For non-oplocked files in strict cache mode we need to write the data
2862 * to the server exactly from the pos to pos+len-1 rather than flush all
2863 * affected pages because it may cause a error with mandatory locks on
2864 * these pages but not on the region from pos to ppos+len-1.
2865 */
2866 written = cifs_user_writev(iocb, from);
2867 if (written > 0 && CIFS_CACHE_READ(cinode)) {
2868 /*
2869 * Windows 7 server can delay breaking level2 oplock if a write
2870 * request comes - break it on the client to prevent reading
2871 * an old data.
2872 */
2873 cifs_zap_mapping(inode);
2874 cifs_dbg(FYI, "Set no oplock for inode=%p after a write operation\n",
2875 inode);
2876 cinode->oplock = 0;
2877 }
2878 out:
2879 cifs_put_writer(cinode);
2880 return written;
2881 }
2882
2883 static struct cifs_readdata *
2884 cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete)
2885 {
2886 struct cifs_readdata *rdata;
2887
2888 rdata = kzalloc(sizeof(*rdata) + (sizeof(struct page *) * nr_pages),
2889 GFP_KERNEL);
2890 if (rdata != NULL) {
2891 kref_init(&rdata->refcount);
2892 INIT_LIST_HEAD(&rdata->list);
2893 init_completion(&rdata->done);
2894 INIT_WORK(&rdata->work, complete);
2895 }
2896
2897 return rdata;
2898 }
2899
2900 void
2901 cifs_readdata_release(struct kref *refcount)
2902 {
2903 struct cifs_readdata *rdata = container_of(refcount,
2904 struct cifs_readdata, refcount);
2905
2906 if (rdata->cfile)
2907 cifsFileInfo_put(rdata->cfile);
2908
2909 kfree(rdata);
2910 }
2911
2912 static int
2913 cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages)
2914 {
2915 int rc = 0;
2916 struct page *page;
2917 unsigned int i;
2918
2919 for (i = 0; i < nr_pages; i++) {
2920 page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
2921 if (!page) {
2922 rc = -ENOMEM;
2923 break;
2924 }
2925 rdata->pages[i] = page;
2926 }
2927
2928 if (rc) {
2929 for (i = 0; i < nr_pages; i++) {
2930 put_page(rdata->pages[i]);
2931 rdata->pages[i] = NULL;
2932 }
2933 }
2934 return rc;
2935 }
2936
2937 static void
2938 cifs_uncached_readdata_release(struct kref *refcount)
2939 {
2940 struct cifs_readdata *rdata = container_of(refcount,
2941 struct cifs_readdata, refcount);
2942 unsigned int i;
2943
2944 kref_put(&rdata->ctx->refcount, cifs_aio_ctx_release);
2945 for (i = 0; i < rdata->nr_pages; i++) {
2946 put_page(rdata->pages[i]);
2947 rdata->pages[i] = NULL;
2948 }
2949 cifs_readdata_release(refcount);
2950 }
2951
2952 /**
2953 * cifs_readdata_to_iov - copy data from pages in response to an iovec
2954 * @rdata: the readdata response with list of pages holding data
2955 * @iter: destination for our data
2956 *
2957 * This function copies data from a list of pages in a readdata response into
2958 * an array of iovecs. It will first calculate where the data should go
2959 * based on the info in the readdata and then copy the data into that spot.
2960 */
2961 static int
2962 cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
2963 {
2964 size_t remaining = rdata->got_bytes;
2965 unsigned int i;
2966
2967 for (i = 0; i < rdata->nr_pages; i++) {
2968 struct page *page = rdata->pages[i];
2969 size_t copy = min_t(size_t, remaining, PAGE_SIZE);
2970 size_t written;
2971
2972 if (unlikely(iter->type & ITER_PIPE)) {
2973 void *addr = kmap_atomic(page);
2974
2975 written = copy_to_iter(addr, copy, iter);
2976 kunmap_atomic(addr);
2977 } else
2978 written = copy_page_to_iter(page, 0, copy, iter);
2979 remaining -= written;
2980 if (written < copy && iov_iter_count(iter) > 0)
2981 break;
2982 }
2983 return remaining ? -EFAULT : 0;
2984 }
2985
2986 static void collect_uncached_read_data(struct cifs_aio_ctx *ctx);
2987
2988 static void
2989 cifs_uncached_readv_complete(struct work_struct *work)
2990 {
2991 struct cifs_readdata *rdata = container_of(work,
2992 struct cifs_readdata, work);
2993
2994 complete(&rdata->done);
2995 collect_uncached_read_data(rdata->ctx);
2996 /* the below call can possibly free the last ref to aio ctx */
2997 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
2998 }
2999
3000 static int
3001 uncached_fill_pages(struct TCP_Server_Info *server,
3002 struct cifs_readdata *rdata, struct iov_iter *iter,
3003 unsigned int len)
3004 {
3005 int result = 0;
3006 unsigned int i;
3007 unsigned int nr_pages = rdata->nr_pages;
3008
3009 rdata->got_bytes = 0;
3010 rdata->tailsz = PAGE_SIZE;
3011 for (i = 0; i < nr_pages; i++) {
3012 struct page *page = rdata->pages[i];
3013 size_t n;
3014
3015 if (len <= 0) {
3016 /* no need to hold page hostage */
3017 rdata->pages[i] = NULL;
3018 rdata->nr_pages--;
3019 put_page(page);
3020 continue;
3021 }
3022 n = len;
3023 if (len >= PAGE_SIZE) {
3024 /* enough data to fill the page */
3025 n = PAGE_SIZE;
3026 len -= n;
3027 } else {
3028 zero_user(page, len, PAGE_SIZE - len);
3029 rdata->tailsz = len;
3030 len = 0;
3031 }
3032 if (iter)
3033 result = copy_page_from_iter(page, 0, n, iter);
3034 else
3035 result = cifs_read_page_from_socket(server, page, n);
3036 if (result < 0)
3037 break;
3038
3039 rdata->got_bytes += result;
3040 }
3041
3042 return rdata->got_bytes > 0 && result != -ECONNABORTED ?
3043 rdata->got_bytes : result;
3044 }
3045
3046 static int
3047 cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
3048 struct cifs_readdata *rdata, unsigned int len)
3049 {
3050 return uncached_fill_pages(server, rdata, NULL, len);
3051 }
3052
3053 static int
3054 cifs_uncached_copy_into_pages(struct TCP_Server_Info *server,
3055 struct cifs_readdata *rdata,
3056 struct iov_iter *iter)
3057 {
3058 return uncached_fill_pages(server, rdata, iter, iter->count);
3059 }
3060
3061 static int
3062 cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
3063 struct cifs_sb_info *cifs_sb, struct list_head *rdata_list,
3064 struct cifs_aio_ctx *ctx)
3065 {
3066 struct cifs_readdata *rdata;
3067 unsigned int npages, rsize, credits;
3068 size_t cur_len;
3069 int rc;
3070 pid_t pid;
3071 struct TCP_Server_Info *server;
3072
3073 server = tlink_tcon(open_file->tlink)->ses->server;
3074
3075 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3076 pid = open_file->pid;
3077 else
3078 pid = current->tgid;
3079
3080 do {
3081 rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
3082 &rsize, &credits);
3083 if (rc)
3084 break;
3085
3086 cur_len = min_t(const size_t, len, rsize);
3087 npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
3088
3089 /* allocate a readdata struct */
3090 rdata = cifs_readdata_alloc(npages,
3091 cifs_uncached_readv_complete);
3092 if (!rdata) {
3093 add_credits_and_wake_if(server, credits, 0);
3094 rc = -ENOMEM;
3095 break;
3096 }
3097
3098 rc = cifs_read_allocate_pages(rdata, npages);
3099 if (rc)
3100 goto error;
3101
3102 rdata->cfile = cifsFileInfo_get(open_file);
3103 rdata->nr_pages = npages;
3104 rdata->offset = offset;
3105 rdata->bytes = cur_len;
3106 rdata->pid = pid;
3107 rdata->pagesz = PAGE_SIZE;
3108 rdata->read_into_pages = cifs_uncached_read_into_pages;
3109 rdata->copy_into_pages = cifs_uncached_copy_into_pages;
3110 rdata->credits = credits;
3111 rdata->ctx = ctx;
3112 kref_get(&ctx->refcount);
3113
3114 if (!rdata->cfile->invalidHandle ||
3115 !(rc = cifs_reopen_file(rdata->cfile, true)))
3116 rc = server->ops->async_readv(rdata);
3117 error:
3118 if (rc) {
3119 add_credits_and_wake_if(server, rdata->credits, 0);
3120 kref_put(&rdata->refcount,
3121 cifs_uncached_readdata_release);
3122 if (rc == -EAGAIN)
3123 continue;
3124 break;
3125 }
3126
3127 list_add_tail(&rdata->list, rdata_list);
3128 offset += cur_len;
3129 len -= cur_len;
3130 } while (len > 0);
3131
3132 return rc;
3133 }
3134
3135 static void
3136 collect_uncached_read_data(struct cifs_aio_ctx *ctx)
3137 {
3138 struct cifs_readdata *rdata, *tmp;
3139 struct iov_iter *to = &ctx->iter;
3140 struct cifs_sb_info *cifs_sb;
3141 struct cifs_tcon *tcon;
3142 unsigned int i;
3143 int rc;
3144
3145 tcon = tlink_tcon(ctx->cfile->tlink);
3146 cifs_sb = CIFS_SB(ctx->cfile->dentry->d_sb);
3147
3148 mutex_lock(&ctx->aio_mutex);
3149
3150 if (list_empty(&ctx->list)) {
3151 mutex_unlock(&ctx->aio_mutex);
3152 return;
3153 }
3154
3155 rc = ctx->rc;
3156 /* the loop below should proceed in the order of increasing offsets */
3157 again:
3158 list_for_each_entry_safe(rdata, tmp, &ctx->list, list) {
3159 if (!rc) {
3160 if (!try_wait_for_completion(&rdata->done)) {
3161 mutex_unlock(&ctx->aio_mutex);
3162 return;
3163 }
3164
3165 if (rdata->result == -EAGAIN) {
3166 /* resend call if it's a retryable error */
3167 struct list_head tmp_list;
3168 unsigned int got_bytes = rdata->got_bytes;
3169
3170 list_del_init(&rdata->list);
3171 INIT_LIST_HEAD(&tmp_list);
3172
3173 /*
3174 * Got a part of data and then reconnect has
3175 * happened -- fill the buffer and continue
3176 * reading.
3177 */
3178 if (got_bytes && got_bytes < rdata->bytes) {
3179 rc = cifs_readdata_to_iov(rdata, to);
3180 if (rc) {
3181 kref_put(&rdata->refcount,
3182 cifs_uncached_readdata_release);
3183 continue;
3184 }
3185 }
3186
3187 rc = cifs_send_async_read(
3188 rdata->offset + got_bytes,
3189 rdata->bytes - got_bytes,
3190 rdata->cfile, cifs_sb,
3191 &tmp_list, ctx);
3192
3193 list_splice(&tmp_list, &ctx->list);
3194
3195 kref_put(&rdata->refcount,
3196 cifs_uncached_readdata_release);
3197 goto again;
3198 } else if (rdata->result)
3199 rc = rdata->result;
3200 else
3201 rc = cifs_readdata_to_iov(rdata, to);
3202
3203 /* if there was a short read -- discard anything left */
3204 if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
3205 rc = -ENODATA;
3206 }
3207 list_del_init(&rdata->list);
3208 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
3209 }
3210
3211 for (i = 0; i < ctx->npages; i++) {
3212 if (ctx->should_dirty)
3213 set_page_dirty(ctx->bv[i].bv_page);
3214 put_page(ctx->bv[i].bv_page);
3215 }
3216
3217 ctx->total_len = ctx->len - iov_iter_count(to);
3218
3219 cifs_stats_bytes_read(tcon, ctx->total_len);
3220
3221 /* mask nodata case */
3222 if (rc == -ENODATA)
3223 rc = 0;
3224
3225 ctx->rc = (rc == 0) ? ctx->total_len : rc;
3226
3227 mutex_unlock(&ctx->aio_mutex);
3228
3229 if (ctx->iocb && ctx->iocb->ki_complete)
3230 ctx->iocb->ki_complete(ctx->iocb, ctx->rc, 0);
3231 else
3232 complete(&ctx->done);
3233 }
3234
3235 ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
3236 {
3237 struct file *file = iocb->ki_filp;
3238 ssize_t rc;
3239 size_t len;
3240 ssize_t total_read = 0;
3241 loff_t offset = iocb->ki_pos;
3242 struct cifs_sb_info *cifs_sb;
3243 struct cifs_tcon *tcon;
3244 struct cifsFileInfo *cfile;
3245 struct cifs_aio_ctx *ctx;
3246
3247 len = iov_iter_count(to);
3248 if (!len)
3249 return 0;
3250
3251 cifs_sb = CIFS_FILE_SB(file);
3252 cfile = file->private_data;
3253 tcon = tlink_tcon(cfile->tlink);
3254
3255 if (!tcon->ses->server->ops->async_readv)
3256 return -ENOSYS;
3257
3258 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
3259 cifs_dbg(FYI, "attempting read on write only file instance\n");
3260
3261 ctx = cifs_aio_ctx_alloc();
3262 if (!ctx)
3263 return -ENOMEM;
3264
3265 ctx->cfile = cifsFileInfo_get(cfile);
3266
3267 if (!is_sync_kiocb(iocb))
3268 ctx->iocb = iocb;
3269
3270 if (to->type == ITER_IOVEC)
3271 ctx->should_dirty = true;
3272
3273 rc = setup_aio_ctx_iter(ctx, to, READ);
3274 if (rc) {
3275 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3276 return rc;
3277 }
3278
3279 len = ctx->len;
3280
3281 /* grab a lock here due to read response handlers can access ctx */
3282 mutex_lock(&ctx->aio_mutex);
3283
3284 rc = cifs_send_async_read(offset, len, cfile, cifs_sb, &ctx->list, ctx);
3285
3286 /* if at least one read request send succeeded, then reset rc */
3287 if (!list_empty(&ctx->list))
3288 rc = 0;
3289
3290 mutex_unlock(&ctx->aio_mutex);
3291
3292 if (rc) {
3293 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3294 return rc;
3295 }
3296
3297 if (!is_sync_kiocb(iocb)) {
3298 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3299 return -EIOCBQUEUED;
3300 }
3301
3302 rc = wait_for_completion_killable(&ctx->done);
3303 if (rc) {
3304 mutex_lock(&ctx->aio_mutex);
3305 ctx->rc = rc = -EINTR;
3306 total_read = ctx->total_len;
3307 mutex_unlock(&ctx->aio_mutex);
3308 } else {
3309 rc = ctx->rc;
3310 total_read = ctx->total_len;
3311 }
3312
3313 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3314
3315 if (total_read) {
3316 iocb->ki_pos += total_read;
3317 return total_read;
3318 }
3319 return rc;
3320 }
3321
3322 ssize_t
3323 cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
3324 {
3325 struct inode *inode = file_inode(iocb->ki_filp);
3326 struct cifsInodeInfo *cinode = CIFS_I(inode);
3327 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
3328 struct cifsFileInfo *cfile = (struct cifsFileInfo *)
3329 iocb->ki_filp->private_data;
3330 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
3331 int rc = -EACCES;
3332
3333 /*
3334 * In strict cache mode we need to read from the server all the time
3335 * if we don't have level II oplock because the server can delay mtime
3336 * change - so we can't make a decision about inode invalidating.
3337 * And we can also fail with pagereading if there are mandatory locks
3338 * on pages affected by this read but not on the region from pos to
3339 * pos+len-1.
3340 */
3341 if (!CIFS_CACHE_READ(cinode))
3342 return cifs_user_readv(iocb, to);
3343
3344 if (cap_unix(tcon->ses) &&
3345 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
3346 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
3347 return generic_file_read_iter(iocb, to);
3348
3349 /*
3350 * We need to hold the sem to be sure nobody modifies lock list
3351 * with a brlock that prevents reading.
3352 */
3353 down_read(&cinode->lock_sem);
3354 if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(to),
3355 tcon->ses->server->vals->shared_lock_type,
3356 NULL, CIFS_READ_OP))
3357 rc = generic_file_read_iter(iocb, to);
3358 up_read(&cinode->lock_sem);
3359 return rc;
3360 }
3361
3362 static ssize_t
3363 cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
3364 {
3365 int rc = -EACCES;
3366 unsigned int bytes_read = 0;
3367 unsigned int total_read;
3368 unsigned int current_read_size;
3369 unsigned int rsize;
3370 struct cifs_sb_info *cifs_sb;
3371 struct cifs_tcon *tcon;
3372 struct TCP_Server_Info *server;
3373 unsigned int xid;
3374 char *cur_offset;
3375 struct cifsFileInfo *open_file;
3376 struct cifs_io_parms io_parms;
3377 int buf_type = CIFS_NO_BUFFER;
3378 __u32 pid;
3379
3380 xid = get_xid();
3381 cifs_sb = CIFS_FILE_SB(file);
3382
3383 /* FIXME: set up handlers for larger reads and/or convert to async */
3384 rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
3385
3386 if (file->private_data == NULL) {
3387 rc = -EBADF;
3388 free_xid(xid);
3389 return rc;
3390 }
3391 open_file = file->private_data;
3392 tcon = tlink_tcon(open_file->tlink);
3393 server = tcon->ses->server;
3394
3395 if (!server->ops->sync_read) {
3396 free_xid(xid);
3397 return -ENOSYS;
3398 }
3399
3400 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3401 pid = open_file->pid;
3402 else
3403 pid = current->tgid;
3404
3405 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
3406 cifs_dbg(FYI, "attempting read on write only file instance\n");
3407
3408 for (total_read = 0, cur_offset = read_data; read_size > total_read;
3409 total_read += bytes_read, cur_offset += bytes_read) {
3410 do {
3411 current_read_size = min_t(uint, read_size - total_read,
3412 rsize);
3413 /*
3414 * For windows me and 9x we do not want to request more
3415 * than it negotiated since it will refuse the read
3416 * then.
3417 */
3418 if ((tcon->ses) && !(tcon->ses->capabilities &
3419 tcon->ses->server->vals->cap_large_files)) {
3420 current_read_size = min_t(uint,
3421 current_read_size, CIFSMaxBufSize);
3422 }
3423 if (open_file->invalidHandle) {
3424 rc = cifs_reopen_file(open_file, true);
3425 if (rc != 0)
3426 break;
3427 }
3428 io_parms.pid = pid;
3429 io_parms.tcon = tcon;
3430 io_parms.offset = *offset;
3431 io_parms.length = current_read_size;
3432 rc = server->ops->sync_read(xid, &open_file->fid, &io_parms,
3433 &bytes_read, &cur_offset,
3434 &buf_type);
3435 } while (rc == -EAGAIN);
3436
3437 if (rc || (bytes_read == 0)) {
3438 if (total_read) {
3439 break;
3440 } else {
3441 free_xid(xid);
3442 return rc;
3443 }
3444 } else {
3445 cifs_stats_bytes_read(tcon, total_read);
3446 *offset += bytes_read;
3447 }
3448 }
3449 free_xid(xid);
3450 return total_read;
3451 }
3452
3453 /*
3454 * If the page is mmap'ed into a process' page tables, then we need to make
3455 * sure that it doesn't change while being written back.
3456 */
3457 static int
3458 cifs_page_mkwrite(struct vm_fault *vmf)
3459 {
3460 struct page *page = vmf->page;
3461
3462 lock_page(page);
3463 return VM_FAULT_LOCKED;
3464 }
3465
3466 static const struct vm_operations_struct cifs_file_vm_ops = {
3467 .fault = filemap_fault,
3468 .map_pages = filemap_map_pages,
3469 .page_mkwrite = cifs_page_mkwrite,
3470 };
3471
3472 int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
3473 {
3474 int xid, rc = 0;
3475 struct inode *inode = file_inode(file);
3476
3477 xid = get_xid();
3478
3479 if (!CIFS_CACHE_READ(CIFS_I(inode)))
3480 rc = cifs_zap_mapping(inode);
3481 if (!rc)
3482 rc = generic_file_mmap(file, vma);
3483 if (!rc)
3484 vma->vm_ops = &cifs_file_vm_ops;
3485
3486 free_xid(xid);
3487 return rc;
3488 }
3489
3490 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
3491 {
3492 int rc, xid;
3493
3494 xid = get_xid();
3495
3496 rc = cifs_revalidate_file(file);
3497 if (rc)
3498 cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
3499 rc);
3500 if (!rc)
3501 rc = generic_file_mmap(file, vma);
3502 if (!rc)
3503 vma->vm_ops = &cifs_file_vm_ops;
3504
3505 free_xid(xid);
3506 return rc;
3507 }
3508
3509 static void
3510 cifs_readv_complete(struct work_struct *work)
3511 {
3512 unsigned int i, got_bytes;
3513 struct cifs_readdata *rdata = container_of(work,
3514 struct cifs_readdata, work);
3515
3516 got_bytes = rdata->got_bytes;
3517 for (i = 0; i < rdata->nr_pages; i++) {
3518 struct page *page = rdata->pages[i];
3519
3520 lru_cache_add_file(page);
3521
3522 if (rdata->result == 0 ||
3523 (rdata->result == -EAGAIN && got_bytes)) {
3524 flush_dcache_page(page);
3525 SetPageUptodate(page);
3526 }
3527
3528 unlock_page(page);
3529
3530 if (rdata->result == 0 ||
3531 (rdata->result == -EAGAIN && got_bytes))
3532 cifs_readpage_to_fscache(rdata->mapping->host, page);
3533
3534 got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
3535
3536 put_page(page);
3537 rdata->pages[i] = NULL;
3538 }
3539 kref_put(&rdata->refcount, cifs_readdata_release);
3540 }
3541
3542 static int
3543 readpages_fill_pages(struct TCP_Server_Info *server,
3544 struct cifs_readdata *rdata, struct iov_iter *iter,
3545 unsigned int len)
3546 {
3547 int result = 0;
3548 unsigned int i;
3549 u64 eof;
3550 pgoff_t eof_index;
3551 unsigned int nr_pages = rdata->nr_pages;
3552
3553 /* determine the eof that the server (probably) has */
3554 eof = CIFS_I(rdata->mapping->host)->server_eof;
3555 eof_index = eof ? (eof - 1) >> PAGE_SHIFT : 0;
3556 cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
3557
3558 rdata->got_bytes = 0;
3559 rdata->tailsz = PAGE_SIZE;
3560 for (i = 0; i < nr_pages; i++) {
3561 struct page *page = rdata->pages[i];
3562 size_t n = PAGE_SIZE;
3563
3564 if (len >= PAGE_SIZE) {
3565 len -= PAGE_SIZE;
3566 } else if (len > 0) {
3567 /* enough for partial page, fill and zero the rest */
3568 zero_user(page, len, PAGE_SIZE - len);
3569 n = rdata->tailsz = len;
3570 len = 0;
3571 } else if (page->index > eof_index) {
3572 /*
3573 * The VFS will not try to do readahead past the
3574 * i_size, but it's possible that we have outstanding
3575 * writes with gaps in the middle and the i_size hasn't
3576 * caught up yet. Populate those with zeroed out pages
3577 * to prevent the VFS from repeatedly attempting to
3578 * fill them until the writes are flushed.
3579 */
3580 zero_user(page, 0, PAGE_SIZE);
3581 lru_cache_add_file(page);
3582 flush_dcache_page(page);
3583 SetPageUptodate(page);
3584 unlock_page(page);
3585 put_page(page);
3586 rdata->pages[i] = NULL;
3587 rdata->nr_pages--;
3588 continue;
3589 } else {
3590 /* no need to hold page hostage */
3591 lru_cache_add_file(page);
3592 unlock_page(page);
3593 put_page(page);
3594 rdata->pages[i] = NULL;
3595 rdata->nr_pages--;
3596 continue;
3597 }
3598
3599 if (iter)
3600 result = copy_page_from_iter(page, 0, n, iter);
3601 else
3602 result = cifs_read_page_from_socket(server, page, n);
3603 if (result < 0)
3604 break;
3605
3606 rdata->got_bytes += result;
3607 }
3608
3609 return rdata->got_bytes > 0 && result != -ECONNABORTED ?
3610 rdata->got_bytes : result;
3611 }
3612
3613 static int
3614 cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
3615 struct cifs_readdata *rdata, unsigned int len)
3616 {
3617 return readpages_fill_pages(server, rdata, NULL, len);
3618 }
3619
3620 static int
3621 cifs_readpages_copy_into_pages(struct TCP_Server_Info *server,
3622 struct cifs_readdata *rdata,
3623 struct iov_iter *iter)
3624 {
3625 return readpages_fill_pages(server, rdata, iter, iter->count);
3626 }
3627
3628 static int
3629 readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
3630 unsigned int rsize, struct list_head *tmplist,
3631 unsigned int *nr_pages, loff_t *offset, unsigned int *bytes)
3632 {
3633 struct page *page, *tpage;
3634 unsigned int expected_index;
3635 int rc;
3636 gfp_t gfp = readahead_gfp_mask(mapping);
3637
3638 INIT_LIST_HEAD(tmplist);
3639
3640 page = list_entry(page_list->prev, struct page, lru);
3641
3642 /*
3643 * Lock the page and put it in the cache. Since no one else
3644 * should have access to this page, we're safe to simply set
3645 * PG_locked without checking it first.
3646 */
3647 __SetPageLocked(page);
3648 rc = add_to_page_cache_locked(page, mapping,
3649 page->index, gfp);
3650
3651 /* give up if we can't stick it in the cache */
3652 if (rc) {
3653 __ClearPageLocked(page);
3654 return rc;
3655 }
3656
3657 /* move first page to the tmplist */
3658 *offset = (loff_t)page->index << PAGE_SHIFT;
3659 *bytes = PAGE_SIZE;
3660 *nr_pages = 1;
3661 list_move_tail(&page->lru, tmplist);
3662
3663 /* now try and add more pages onto the request */
3664 expected_index = page->index + 1;
3665 list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {
3666 /* discontinuity ? */
3667 if (page->index != expected_index)
3668 break;
3669
3670 /* would this page push the read over the rsize? */
3671 if (*bytes + PAGE_SIZE > rsize)
3672 break;
3673
3674 __SetPageLocked(page);
3675 if (add_to_page_cache_locked(page, mapping, page->index, gfp)) {
3676 __ClearPageLocked(page);
3677 break;
3678 }
3679 list_move_tail(&page->lru, tmplist);
3680 (*bytes) += PAGE_SIZE;
3681 expected_index++;
3682 (*nr_pages)++;
3683 }
3684 return rc;
3685 }
3686
3687 static int cifs_readpages(struct file *file, struct address_space *mapping,
3688 struct list_head *page_list, unsigned num_pages)
3689 {
3690 int rc;
3691 struct list_head tmplist;
3692 struct cifsFileInfo *open_file = file->private_data;
3693 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
3694 struct TCP_Server_Info *server;
3695 pid_t pid;
3696
3697 /*
3698 * Reads as many pages as possible from fscache. Returns -ENOBUFS
3699 * immediately if the cookie is negative
3700 *
3701 * After this point, every page in the list might have PG_fscache set,
3702 * so we will need to clean that up off of every page we don't use.
3703 */
3704 rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
3705 &num_pages);
3706 if (rc == 0)
3707 return rc;
3708
3709 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3710 pid = open_file->pid;
3711 else
3712 pid = current->tgid;
3713
3714 rc = 0;
3715 server = tlink_tcon(open_file->tlink)->ses->server;
3716
3717 cifs_dbg(FYI, "%s: file=%p mapping=%p num_pages=%u\n",
3718 __func__, file, mapping, num_pages);
3719
3720 /*
3721 * Start with the page at end of list and move it to private
3722 * list. Do the same with any following pages until we hit
3723 * the rsize limit, hit an index discontinuity, or run out of
3724 * pages. Issue the async read and then start the loop again
3725 * until the list is empty.
3726 *
3727 * Note that list order is important. The page_list is in
3728 * the order of declining indexes. When we put the pages in
3729 * the rdata->pages, then we want them in increasing order.
3730 */
3731 while (!list_empty(page_list)) {
3732 unsigned int i, nr_pages, bytes, rsize;
3733 loff_t offset;
3734 struct page *page, *tpage;
3735 struct cifs_readdata *rdata;
3736 unsigned credits;
3737
3738 rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
3739 &rsize, &credits);
3740 if (rc)
3741 break;
3742
3743 /*
3744 * Give up immediately if rsize is too small to read an entire
3745 * page. The VFS will fall back to readpage. We should never
3746 * reach this point however since we set ra_pages to 0 when the
3747 * rsize is smaller than a cache page.
3748 */
3749 if (unlikely(rsize < PAGE_SIZE)) {
3750 add_credits_and_wake_if(server, credits, 0);
3751 return 0;
3752 }
3753
3754 rc = readpages_get_pages(mapping, page_list, rsize, &tmplist,
3755 &nr_pages, &offset, &bytes);
3756 if (rc) {
3757 add_credits_and_wake_if(server, credits, 0);
3758 break;
3759 }
3760
3761 rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
3762 if (!rdata) {
3763 /* best to give up if we're out of mem */
3764 list_for_each_entry_safe(page, tpage, &tmplist, lru) {
3765 list_del(&page->lru);
3766 lru_cache_add_file(page);
3767 unlock_page(page);
3768 put_page(page);
3769 }
3770 rc = -ENOMEM;
3771 add_credits_and_wake_if(server, credits, 0);
3772 break;
3773 }
3774
3775 rdata->cfile = cifsFileInfo_get(open_file);
3776 rdata->mapping = mapping;
3777 rdata->offset = offset;
3778 rdata->bytes = bytes;
3779 rdata->pid = pid;
3780 rdata->pagesz = PAGE_SIZE;
3781 rdata->read_into_pages = cifs_readpages_read_into_pages;
3782 rdata->copy_into_pages = cifs_readpages_copy_into_pages;
3783 rdata->credits = credits;
3784
3785 list_for_each_entry_safe(page, tpage, &tmplist, lru) {
3786 list_del(&page->lru);
3787 rdata->pages[rdata->nr_pages++] = page;
3788 }
3789
3790 if (!rdata->cfile->invalidHandle ||
3791 !(rc = cifs_reopen_file(rdata->cfile, true)))
3792 rc = server->ops->async_readv(rdata);
3793 if (rc) {
3794 add_credits_and_wake_if(server, rdata->credits, 0);
3795 for (i = 0; i < rdata->nr_pages; i++) {
3796 page = rdata->pages[i];
3797 lru_cache_add_file(page);
3798 unlock_page(page);
3799 put_page(page);
3800 }
3801 /* Fallback to the readpage in error/reconnect cases */
3802 kref_put(&rdata->refcount, cifs_readdata_release);
3803 break;
3804 }
3805
3806 kref_put(&rdata->refcount, cifs_readdata_release);
3807 }
3808
3809 /* Any pages that have been shown to fscache but didn't get added to
3810 * the pagecache must be uncached before they get returned to the
3811 * allocator.
3812 */
3813 cifs_fscache_readpages_cancel(mapping->host, page_list);
3814 return rc;
3815 }
3816
3817 /*
3818 * cifs_readpage_worker must be called with the page pinned
3819 */
3820 static int cifs_readpage_worker(struct file *file, struct page *page,
3821 loff_t *poffset)
3822 {
3823 char *read_data;
3824 int rc;
3825
3826 /* Is the page cached? */
3827 rc = cifs_readpage_from_fscache(file_inode(file), page);
3828 if (rc == 0)
3829 goto read_complete;
3830
3831 read_data = kmap(page);
3832 /* for reads over a certain size could initiate async read ahead */
3833
3834 rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
3835
3836 if (rc < 0)
3837 goto io_error;
3838 else
3839 cifs_dbg(FYI, "Bytes read %d\n", rc);
3840
3841 file_inode(file)->i_atime =
3842 current_time(file_inode(file));
3843
3844 if (PAGE_SIZE > rc)
3845 memset(read_data + rc, 0, PAGE_SIZE - rc);
3846
3847 flush_dcache_page(page);
3848 SetPageUptodate(page);
3849
3850 /* send this page to the cache */
3851 cifs_readpage_to_fscache(file_inode(file), page);
3852
3853 rc = 0;
3854
3855 io_error:
3856 kunmap(page);
3857 unlock_page(page);
3858
3859 read_complete:
3860 return rc;
3861 }
3862
3863 static int cifs_readpage(struct file *file, struct page *page)
3864 {
3865 loff_t offset = (loff_t)page->index << PAGE_SHIFT;
3866 int rc = -EACCES;
3867 unsigned int xid;
3868
3869 xid = get_xid();
3870
3871 if (file->private_data == NULL) {
3872 rc = -EBADF;
3873 free_xid(xid);
3874 return rc;
3875 }
3876
3877 cifs_dbg(FYI, "readpage %p at offset %d 0x%x\n",
3878 page, (int)offset, (int)offset);
3879
3880 rc = cifs_readpage_worker(file, page, &offset);
3881
3882 free_xid(xid);
3883 return rc;
3884 }
3885
3886 static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
3887 {
3888 struct cifsFileInfo *open_file;
3889 struct cifs_tcon *tcon =
3890 cifs_sb_master_tcon(CIFS_SB(cifs_inode->vfs_inode.i_sb));
3891
3892 spin_lock(&tcon->open_file_lock);
3893 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
3894 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
3895 spin_unlock(&tcon->open_file_lock);
3896 return 1;
3897 }
3898 }
3899 spin_unlock(&tcon->open_file_lock);
3900 return 0;
3901 }
3902
3903 /* We do not want to update the file size from server for inodes
3904 open for write - to avoid races with writepage extending
3905 the file - in the future we could consider allowing
3906 refreshing the inode only on increases in the file size
3907 but this is tricky to do without racing with writebehind
3908 page caching in the current Linux kernel design */
3909 bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
3910 {
3911 if (!cifsInode)
3912 return true;
3913
3914 if (is_inode_writable(cifsInode)) {
3915 /* This inode is open for write at least once */
3916 struct cifs_sb_info *cifs_sb;
3917
3918 cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
3919 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
3920 /* since no page cache to corrupt on directio
3921 we can change size safely */
3922 return true;
3923 }
3924
3925 if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
3926 return true;
3927
3928 return false;
3929 } else
3930 return true;
3931 }
3932
3933 static int cifs_write_begin(struct file *file, struct address_space *mapping,
3934 loff_t pos, unsigned len, unsigned flags,
3935 struct page **pagep, void **fsdata)
3936 {
3937 int oncethru = 0;
3938 pgoff_t index = pos >> PAGE_SHIFT;
3939 loff_t offset = pos & (PAGE_SIZE - 1);
3940 loff_t page_start = pos & PAGE_MASK;
3941 loff_t i_size;
3942 struct page *page;
3943 int rc = 0;
3944
3945 cifs_dbg(FYI, "write_begin from %lld len %d\n", (long long)pos, len);
3946
3947 start:
3948 page = grab_cache_page_write_begin(mapping, index, flags);
3949 if (!page) {
3950 rc = -ENOMEM;
3951 goto out;
3952 }
3953
3954 if (PageUptodate(page))
3955 goto out;
3956
3957 /*
3958 * If we write a full page it will be up to date, no need to read from
3959 * the server. If the write is short, we'll end up doing a sync write
3960 * instead.
3961 */
3962 if (len == PAGE_SIZE)
3963 goto out;
3964
3965 /*
3966 * optimize away the read when we have an oplock, and we're not
3967 * expecting to use any of the data we'd be reading in. That
3968 * is, when the page lies beyond the EOF, or straddles the EOF
3969 * and the write will cover all of the existing data.
3970 */
3971 if (CIFS_CACHE_READ(CIFS_I(mapping->host))) {
3972 i_size = i_size_read(mapping->host);
3973 if (page_start >= i_size ||
3974 (offset == 0 && (pos + len) >= i_size)) {
3975 zero_user_segments(page, 0, offset,
3976 offset + len,
3977 PAGE_SIZE);
3978 /*
3979 * PageChecked means that the parts of the page
3980 * to which we're not writing are considered up
3981 * to date. Once the data is copied to the
3982 * page, it can be set uptodate.
3983 */
3984 SetPageChecked(page);
3985 goto out;
3986 }
3987 }
3988
3989 if ((file->f_flags & O_ACCMODE) != O_WRONLY && !oncethru) {
3990 /*
3991 * might as well read a page, it is fast enough. If we get
3992 * an error, we don't need to return it. cifs_write_end will
3993 * do a sync write instead since PG_uptodate isn't set.
3994 */
3995 cifs_readpage_worker(file, page, &page_start);
3996 put_page(page);
3997 oncethru = 1;
3998 goto start;
3999 } else {
4000 /* we could try using another file handle if there is one -
4001 but how would we lock it to prevent close of that handle
4002 racing with this read? In any case
4003 this will be written out by write_end so is fine */
4004 }
4005 out:
4006 *pagep = page;
4007 return rc;
4008 }
4009
4010 static int cifs_release_page(struct page *page, gfp_t gfp)
4011 {
4012 if (PagePrivate(page))
4013 return 0;
4014
4015 return cifs_fscache_release_page(page, gfp);
4016 }
4017
4018 static void cifs_invalidate_page(struct page *page, unsigned int offset,
4019 unsigned int length)
4020 {
4021 struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
4022
4023 if (offset == 0 && length == PAGE_SIZE)
4024 cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
4025 }
4026
4027 static int cifs_launder_page(struct page *page)
4028 {
4029 int rc = 0;
4030 loff_t range_start = page_offset(page);
4031 loff_t range_end = range_start + (loff_t)(PAGE_SIZE - 1);
4032 struct writeback_control wbc = {
4033 .sync_mode = WB_SYNC_ALL,
4034 .nr_to_write = 0,
4035 .range_start = range_start,
4036 .range_end = range_end,
4037 };
4038
4039 cifs_dbg(FYI, "Launder page: %p\n", page);
4040
4041 if (clear_page_dirty_for_io(page))
4042 rc = cifs_writepage_locked(page, &wbc);
4043
4044 cifs_fscache_invalidate_page(page, page->mapping->host);
4045 return rc;
4046 }
4047
4048 void cifs_oplock_break(struct work_struct *work)
4049 {
4050 struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
4051 oplock_break);
4052 struct inode *inode = d_inode(cfile->dentry);
4053 struct cifsInodeInfo *cinode = CIFS_I(inode);
4054 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
4055 struct TCP_Server_Info *server = tcon->ses->server;
4056 int rc = 0;
4057
4058 wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
4059 TASK_UNINTERRUPTIBLE);
4060
4061 server->ops->downgrade_oplock(server, cinode,
4062 test_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2, &cinode->flags));
4063
4064 if (!CIFS_CACHE_WRITE(cinode) && CIFS_CACHE_READ(cinode) &&
4065 cifs_has_mand_locks(cinode)) {
4066 cifs_dbg(FYI, "Reset oplock to None for inode=%p due to mand locks\n",
4067 inode);
4068 cinode->oplock = 0;
4069 }
4070
4071 if (inode && S_ISREG(inode->i_mode)) {
4072 if (CIFS_CACHE_READ(cinode))
4073 break_lease(inode, O_RDONLY);
4074 else
4075 break_lease(inode, O_WRONLY);
4076 rc = filemap_fdatawrite(inode->i_mapping);
4077 if (!CIFS_CACHE_READ(cinode)) {
4078 rc = filemap_fdatawait(inode->i_mapping);
4079 mapping_set_error(inode->i_mapping, rc);
4080 cifs_zap_mapping(inode);
4081 }
4082 cifs_dbg(FYI, "Oplock flush inode %p rc %d\n", inode, rc);
4083 }
4084
4085 rc = cifs_push_locks(cfile);
4086 if (rc)
4087 cifs_dbg(VFS, "Push locks rc = %d\n", rc);
4088
4089 /*
4090 * releasing stale oplock after recent reconnect of smb session using
4091 * a now incorrect file handle is not a data integrity issue but do
4092 * not bother sending an oplock release if session to server still is
4093 * disconnected since oplock already released by the server
4094 */
4095 if (!cfile->oplock_break_cancelled) {
4096 rc = tcon->ses->server->ops->oplock_response(tcon, &cfile->fid,
4097 cinode);
4098 cifs_dbg(FYI, "Oplock release rc = %d\n", rc);
4099 }
4100 cifs_done_oplock_break(cinode);
4101 }
4102
4103 /*
4104 * The presence of cifs_direct_io() in the address space ops vector
4105 * allowes open() O_DIRECT flags which would have failed otherwise.
4106 *
4107 * In the non-cached mode (mount with cache=none), we shunt off direct read and write requests
4108 * so this method should never be called.
4109 *
4110 * Direct IO is not yet supported in the cached mode.
4111 */
4112 static ssize_t
4113 cifs_direct_io(struct kiocb *iocb, struct iov_iter *iter)
4114 {
4115 /*
4116 * FIXME
4117 * Eventually need to support direct IO for non forcedirectio mounts
4118 */
4119 return -EINVAL;
4120 }
4121
4122
4123 const struct address_space_operations cifs_addr_ops = {
4124 .readpage = cifs_readpage,
4125 .readpages = cifs_readpages,
4126 .writepage = cifs_writepage,
4127 .writepages = cifs_writepages,
4128 .write_begin = cifs_write_begin,
4129 .write_end = cifs_write_end,
4130 .set_page_dirty = __set_page_dirty_nobuffers,
4131 .releasepage = cifs_release_page,
4132 .direct_IO = cifs_direct_io,
4133 .invalidatepage = cifs_invalidate_page,
4134 .launder_page = cifs_launder_page,
4135 };
4136
4137 /*
4138 * cifs_readpages requires the server to support a buffer large enough to
4139 * contain the header plus one complete page of data. Otherwise, we need
4140 * to leave cifs_readpages out of the address space operations.
4141 */
4142 const struct address_space_operations cifs_addr_ops_smallbuf = {
4143 .readpage = cifs_readpage,
4144 .writepage = cifs_writepage,
4145 .writepages = cifs_writepages,
4146 .write_begin = cifs_write_begin,
4147 .write_end = cifs_write_end,
4148 .set_page_dirty = __set_page_dirty_nobuffers,
4149 .releasepage = cifs_release_page,
4150 .invalidatepage = cifs_invalidate_page,
4151 .launder_page = cifs_launder_page,
4152 };
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