1 // SPDX-License-Identifier: LGPL-2.1
2 /*
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 */
11 #include <linux/fs.h>
12 #include <linux/backing-dev.h>
13 #include <linux/stat.h>
14 #include <linux/fcntl.h>
15 #include <linux/pagemap.h>
16 #include <linux/pagevec.h>
17 #include <linux/writeback.h>
18 #include <linux/task_io_accounting_ops.h>
19 #include <linux/delay.h>
20 #include <linux/mount.h>
21 #include <linux/slab.h>
22 #include <linux/swap.h>
23 #include <linux/mm.h>
24 #include <asm/div64.h>
25 #include "cifsfs.h"
26 #include "cifspdu.h"
27 #include "cifsglob.h"
28 #include "cifsproto.h"
29 #include "smb2proto.h"
30 #include "cifs_unicode.h"
31 #include "cifs_debug.h"
32 #include "cifs_fs_sb.h"
33 #include "fscache.h"
34 #include "smbdirect.h"
35 #include "fs_context.h"
36 #include "cifs_ioctl.h"
37 #include "cached_dir.h"
38
39 /*
40 * Mark as invalid, all open files on tree connections since they
41 * were closed when session to server was lost.
42 */
43 void
cifs_mark_open_files_invalid(struct cifs_tcon * tcon)44 cifs_mark_open_files_invalid(struct cifs_tcon *tcon)
45 {
46 struct cifsFileInfo *open_file = NULL;
47 struct list_head *tmp;
48 struct list_head *tmp1;
49
50 /* only send once per connect */
51 spin_lock(&tcon->ses->ses_lock);
52 if ((tcon->ses->ses_status != SES_GOOD) || (tcon->status != TID_NEED_RECON)) {
53 spin_unlock(&tcon->ses->ses_lock);
54 return;
55 }
56 tcon->status = TID_IN_FILES_INVALIDATE;
57 spin_unlock(&tcon->ses->ses_lock);
58
59 /* list all files open on tree connection and mark them invalid */
60 spin_lock(&tcon->open_file_lock);
61 list_for_each_safe(tmp, tmp1, &tcon->openFileList) {
62 open_file = list_entry(tmp, struct cifsFileInfo, tlist);
63 open_file->invalidHandle = true;
64 open_file->oplock_break_cancelled = true;
65 }
66 spin_unlock(&tcon->open_file_lock);
67
68 invalidate_all_cached_dirs(tcon);
69 spin_lock(&tcon->tc_lock);
70 if (tcon->status == TID_IN_FILES_INVALIDATE)
71 tcon->status = TID_NEED_TCON;
72 spin_unlock(&tcon->tc_lock);
73
74 /*
75 * BB Add call to invalidate_inodes(sb) for all superblocks mounted
76 * to this tcon.
77 */
78 }
79
cifs_convert_flags(unsigned int flags)80 static inline int cifs_convert_flags(unsigned int flags)
81 {
82 if ((flags & O_ACCMODE) == O_RDONLY)
83 return GENERIC_READ;
84 else if ((flags & O_ACCMODE) == O_WRONLY)
85 return GENERIC_WRITE;
86 else if ((flags & O_ACCMODE) == O_RDWR) {
87 /* GENERIC_ALL is too much permission to request
88 can cause unnecessary access denied on create */
89 /* return GENERIC_ALL; */
90 return (GENERIC_READ | GENERIC_WRITE);
91 }
92
93 return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
94 FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
95 FILE_READ_DATA);
96 }
97
98 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
cifs_posix_convert_flags(unsigned int flags)99 static u32 cifs_posix_convert_flags(unsigned int flags)
100 {
101 u32 posix_flags = 0;
102
103 if ((flags & O_ACCMODE) == O_RDONLY)
104 posix_flags = SMB_O_RDONLY;
105 else if ((flags & O_ACCMODE) == O_WRONLY)
106 posix_flags = SMB_O_WRONLY;
107 else if ((flags & O_ACCMODE) == O_RDWR)
108 posix_flags = SMB_O_RDWR;
109
110 if (flags & O_CREAT) {
111 posix_flags |= SMB_O_CREAT;
112 if (flags & O_EXCL)
113 posix_flags |= SMB_O_EXCL;
114 } else if (flags & O_EXCL)
115 cifs_dbg(FYI, "Application %s pid %d has incorrectly set O_EXCL flag but not O_CREAT on file open. Ignoring O_EXCL\n",
116 current->comm, current->tgid);
117
118 if (flags & O_TRUNC)
119 posix_flags |= SMB_O_TRUNC;
120 /* be safe and imply O_SYNC for O_DSYNC */
121 if (flags & O_DSYNC)
122 posix_flags |= SMB_O_SYNC;
123 if (flags & O_DIRECTORY)
124 posix_flags |= SMB_O_DIRECTORY;
125 if (flags & O_NOFOLLOW)
126 posix_flags |= SMB_O_NOFOLLOW;
127 if (flags & O_DIRECT)
128 posix_flags |= SMB_O_DIRECT;
129
130 return posix_flags;
131 }
132 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
133
cifs_get_disposition(unsigned int flags)134 static inline int cifs_get_disposition(unsigned int flags)
135 {
136 if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
137 return FILE_CREATE;
138 else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
139 return FILE_OVERWRITE_IF;
140 else if ((flags & O_CREAT) == O_CREAT)
141 return FILE_OPEN_IF;
142 else if ((flags & O_TRUNC) == O_TRUNC)
143 return FILE_OVERWRITE;
144 else
145 return FILE_OPEN;
146 }
147
148 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
cifs_posix_open(const char * full_path,struct inode ** pinode,struct super_block * sb,int mode,unsigned int f_flags,__u32 * poplock,__u16 * pnetfid,unsigned int xid)149 int cifs_posix_open(const char *full_path, struct inode **pinode,
150 struct super_block *sb, int mode, unsigned int f_flags,
151 __u32 *poplock, __u16 *pnetfid, unsigned int xid)
152 {
153 int rc;
154 FILE_UNIX_BASIC_INFO *presp_data;
155 __u32 posix_flags = 0;
156 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
157 struct cifs_fattr fattr;
158 struct tcon_link *tlink;
159 struct cifs_tcon *tcon;
160
161 cifs_dbg(FYI, "posix open %s\n", full_path);
162
163 presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
164 if (presp_data == NULL)
165 return -ENOMEM;
166
167 tlink = cifs_sb_tlink(cifs_sb);
168 if (IS_ERR(tlink)) {
169 rc = PTR_ERR(tlink);
170 goto posix_open_ret;
171 }
172
173 tcon = tlink_tcon(tlink);
174 mode &= ~current_umask();
175
176 posix_flags = cifs_posix_convert_flags(f_flags);
177 rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
178 poplock, full_path, cifs_sb->local_nls,
179 cifs_remap(cifs_sb));
180 cifs_put_tlink(tlink);
181
182 if (rc)
183 goto posix_open_ret;
184
185 if (presp_data->Type == cpu_to_le32(-1))
186 goto posix_open_ret; /* open ok, caller does qpathinfo */
187
188 if (!pinode)
189 goto posix_open_ret; /* caller does not need info */
190
191 cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
192
193 /* get new inode and set it up */
194 if (*pinode == NULL) {
195 cifs_fill_uniqueid(sb, &fattr);
196 *pinode = cifs_iget(sb, &fattr);
197 if (!*pinode) {
198 rc = -ENOMEM;
199 goto posix_open_ret;
200 }
201 } else {
202 cifs_revalidate_mapping(*pinode);
203 rc = cifs_fattr_to_inode(*pinode, &fattr);
204 }
205
206 posix_open_ret:
207 kfree(presp_data);
208 return rc;
209 }
210 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
211
cifs_nt_open(const char * full_path,struct inode * inode,struct cifs_sb_info * cifs_sb,struct cifs_tcon * tcon,unsigned int f_flags,__u32 * oplock,struct cifs_fid * fid,unsigned int xid,struct cifs_open_info_data * buf)212 static int cifs_nt_open(const char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
213 struct cifs_tcon *tcon, unsigned int f_flags, __u32 *oplock,
214 struct cifs_fid *fid, unsigned int xid, struct cifs_open_info_data *buf)
215 {
216 int rc;
217 int desired_access;
218 int disposition;
219 int create_options = CREATE_NOT_DIR;
220 struct TCP_Server_Info *server = tcon->ses->server;
221 struct cifs_open_parms oparms;
222
223 if (!server->ops->open)
224 return -ENOSYS;
225
226 desired_access = cifs_convert_flags(f_flags);
227
228 /*********************************************************************
229 * open flag mapping table:
230 *
231 * POSIX Flag CIFS Disposition
232 * ---------- ----------------
233 * O_CREAT FILE_OPEN_IF
234 * O_CREAT | O_EXCL FILE_CREATE
235 * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
236 * O_TRUNC FILE_OVERWRITE
237 * none of the above FILE_OPEN
238 *
239 * Note that there is not a direct match between disposition
240 * FILE_SUPERSEDE (ie create whether or not file exists although
241 * O_CREAT | O_TRUNC is similar but truncates the existing
242 * file rather than creating a new file as FILE_SUPERSEDE does
243 * (which uses the attributes / metadata passed in on open call)
244 *?
245 *? O_SYNC is a reasonable match to CIFS writethrough flag
246 *? and the read write flags match reasonably. O_LARGEFILE
247 *? is irrelevant because largefile support is always used
248 *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
249 * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
250 *********************************************************************/
251
252 disposition = cifs_get_disposition(f_flags);
253
254 /* BB pass O_SYNC flag through on file attributes .. BB */
255
256 /* O_SYNC also has bit for O_DSYNC so following check picks up either */
257 if (f_flags & O_SYNC)
258 create_options |= CREATE_WRITE_THROUGH;
259
260 if (f_flags & O_DIRECT)
261 create_options |= CREATE_NO_BUFFER;
262
263 oparms.tcon = tcon;
264 oparms.cifs_sb = cifs_sb;
265 oparms.desired_access = desired_access;
266 oparms.create_options = cifs_create_options(cifs_sb, create_options);
267 oparms.disposition = disposition;
268 oparms.path = full_path;
269 oparms.fid = fid;
270 oparms.reconnect = false;
271
272 rc = server->ops->open(xid, &oparms, oplock, buf);
273 if (rc)
274 return rc;
275
276 /* TODO: Add support for calling posix query info but with passing in fid */
277 if (tcon->unix_ext)
278 rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
279 xid);
280 else
281 rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
282 xid, fid);
283
284 if (rc) {
285 server->ops->close(xid, tcon, fid);
286 if (rc == -ESTALE)
287 rc = -EOPENSTALE;
288 }
289
290 return rc;
291 }
292
293 static bool
cifs_has_mand_locks(struct cifsInodeInfo * cinode)294 cifs_has_mand_locks(struct cifsInodeInfo *cinode)
295 {
296 struct cifs_fid_locks *cur;
297 bool has_locks = false;
298
299 down_read(&cinode->lock_sem);
300 list_for_each_entry(cur, &cinode->llist, llist) {
301 if (!list_empty(&cur->locks)) {
302 has_locks = true;
303 break;
304 }
305 }
306 up_read(&cinode->lock_sem);
307 return has_locks;
308 }
309
310 void
cifs_down_write(struct rw_semaphore * sem)311 cifs_down_write(struct rw_semaphore *sem)
312 {
313 while (!down_write_trylock(sem))
314 msleep(10);
315 }
316
317 static void cifsFileInfo_put_work(struct work_struct *work);
318
cifs_new_fileinfo(struct cifs_fid * fid,struct file * file,struct tcon_link * tlink,__u32 oplock,const char * symlink_target)319 struct cifsFileInfo *cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
320 struct tcon_link *tlink, __u32 oplock,
321 const char *symlink_target)
322 {
323 struct dentry *dentry = file_dentry(file);
324 struct inode *inode = d_inode(dentry);
325 struct cifsInodeInfo *cinode = CIFS_I(inode);
326 struct cifsFileInfo *cfile;
327 struct cifs_fid_locks *fdlocks;
328 struct cifs_tcon *tcon = tlink_tcon(tlink);
329 struct TCP_Server_Info *server = tcon->ses->server;
330
331 cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
332 if (cfile == NULL)
333 return cfile;
334
335 fdlocks = kzalloc(sizeof(struct cifs_fid_locks), GFP_KERNEL);
336 if (!fdlocks) {
337 kfree(cfile);
338 return NULL;
339 }
340
341 if (symlink_target) {
342 cfile->symlink_target = kstrdup(symlink_target, GFP_KERNEL);
343 if (!cfile->symlink_target) {
344 kfree(fdlocks);
345 kfree(cfile);
346 return NULL;
347 }
348 }
349
350 INIT_LIST_HEAD(&fdlocks->locks);
351 fdlocks->cfile = cfile;
352 cfile->llist = fdlocks;
353
354 cfile->count = 1;
355 cfile->pid = current->tgid;
356 cfile->uid = current_fsuid();
357 cfile->dentry = dget(dentry);
358 cfile->f_flags = file->f_flags;
359 cfile->invalidHandle = false;
360 cfile->deferred_close_scheduled = false;
361 cfile->tlink = cifs_get_tlink(tlink);
362 INIT_WORK(&cfile->oplock_break, cifs_oplock_break);
363 INIT_WORK(&cfile->put, cifsFileInfo_put_work);
364 INIT_DELAYED_WORK(&cfile->deferred, smb2_deferred_work_close);
365 mutex_init(&cfile->fh_mutex);
366 spin_lock_init(&cfile->file_info_lock);
367
368 cifs_sb_active(inode->i_sb);
369
370 /*
371 * If the server returned a read oplock and we have mandatory brlocks,
372 * set oplock level to None.
373 */
374 if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
375 cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
376 oplock = 0;
377 }
378
379 cifs_down_write(&cinode->lock_sem);
380 list_add(&fdlocks->llist, &cinode->llist);
381 up_write(&cinode->lock_sem);
382
383 spin_lock(&tcon->open_file_lock);
384 if (fid->pending_open->oplock != CIFS_OPLOCK_NO_CHANGE && oplock)
385 oplock = fid->pending_open->oplock;
386 list_del(&fid->pending_open->olist);
387
388 fid->purge_cache = false;
389 server->ops->set_fid(cfile, fid, oplock);
390
391 list_add(&cfile->tlist, &tcon->openFileList);
392 atomic_inc(&tcon->num_local_opens);
393
394 /* if readable file instance put first in list*/
395 spin_lock(&cinode->open_file_lock);
396 if (file->f_mode & FMODE_READ)
397 list_add(&cfile->flist, &cinode->openFileList);
398 else
399 list_add_tail(&cfile->flist, &cinode->openFileList);
400 spin_unlock(&cinode->open_file_lock);
401 spin_unlock(&tcon->open_file_lock);
402
403 if (fid->purge_cache)
404 cifs_zap_mapping(inode);
405
406 file->private_data = cfile;
407 return cfile;
408 }
409
410 struct cifsFileInfo *
cifsFileInfo_get(struct cifsFileInfo * cifs_file)411 cifsFileInfo_get(struct cifsFileInfo *cifs_file)
412 {
413 spin_lock(&cifs_file->file_info_lock);
414 cifsFileInfo_get_locked(cifs_file);
415 spin_unlock(&cifs_file->file_info_lock);
416 return cifs_file;
417 }
418
cifsFileInfo_put_final(struct cifsFileInfo * cifs_file)419 static void cifsFileInfo_put_final(struct cifsFileInfo *cifs_file)
420 {
421 struct inode *inode = d_inode(cifs_file->dentry);
422 struct cifsInodeInfo *cifsi = CIFS_I(inode);
423 struct cifsLockInfo *li, *tmp;
424 struct super_block *sb = inode->i_sb;
425
426 /*
427 * Delete any outstanding lock records. We'll lose them when the file
428 * is closed anyway.
429 */
430 cifs_down_write(&cifsi->lock_sem);
431 list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
432 list_del(&li->llist);
433 cifs_del_lock_waiters(li);
434 kfree(li);
435 }
436 list_del(&cifs_file->llist->llist);
437 kfree(cifs_file->llist);
438 up_write(&cifsi->lock_sem);
439
440 cifs_put_tlink(cifs_file->tlink);
441 dput(cifs_file->dentry);
442 cifs_sb_deactive(sb);
443 kfree(cifs_file->symlink_target);
444 kfree(cifs_file);
445 }
446
cifsFileInfo_put_work(struct work_struct * work)447 static void cifsFileInfo_put_work(struct work_struct *work)
448 {
449 struct cifsFileInfo *cifs_file = container_of(work,
450 struct cifsFileInfo, put);
451
452 cifsFileInfo_put_final(cifs_file);
453 }
454
455 /**
456 * cifsFileInfo_put - release a reference of file priv data
457 *
458 * Always potentially wait for oplock handler. See _cifsFileInfo_put().
459 *
460 * @cifs_file: cifs/smb3 specific info (eg refcounts) for an open file
461 */
cifsFileInfo_put(struct cifsFileInfo * cifs_file)462 void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
463 {
464 _cifsFileInfo_put(cifs_file, true, true);
465 }
466
467 /**
468 * _cifsFileInfo_put - release a reference of file priv data
469 *
470 * This may involve closing the filehandle @cifs_file out on the
471 * server. Must be called without holding tcon->open_file_lock,
472 * cinode->open_file_lock and cifs_file->file_info_lock.
473 *
474 * If @wait_for_oplock_handler is true and we are releasing the last
475 * reference, wait for any running oplock break handler of the file
476 * and cancel any pending one.
477 *
478 * @cifs_file: cifs/smb3 specific info (eg refcounts) for an open file
479 * @wait_oplock_handler: must be false if called from oplock_break_handler
480 * @offload: not offloaded on close and oplock breaks
481 *
482 */
_cifsFileInfo_put(struct cifsFileInfo * cifs_file,bool wait_oplock_handler,bool offload)483 void _cifsFileInfo_put(struct cifsFileInfo *cifs_file,
484 bool wait_oplock_handler, bool offload)
485 {
486 struct inode *inode = d_inode(cifs_file->dentry);
487 struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink);
488 struct TCP_Server_Info *server = tcon->ses->server;
489 struct cifsInodeInfo *cifsi = CIFS_I(inode);
490 struct super_block *sb = inode->i_sb;
491 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
492 struct cifs_fid fid = {};
493 struct cifs_pending_open open;
494 bool oplock_break_cancelled;
495
496 spin_lock(&tcon->open_file_lock);
497 spin_lock(&cifsi->open_file_lock);
498 spin_lock(&cifs_file->file_info_lock);
499 if (--cifs_file->count > 0) {
500 spin_unlock(&cifs_file->file_info_lock);
501 spin_unlock(&cifsi->open_file_lock);
502 spin_unlock(&tcon->open_file_lock);
503 return;
504 }
505 spin_unlock(&cifs_file->file_info_lock);
506
507 if (server->ops->get_lease_key)
508 server->ops->get_lease_key(inode, &fid);
509
510 /* store open in pending opens to make sure we don't miss lease break */
511 cifs_add_pending_open_locked(&fid, cifs_file->tlink, &open);
512
513 /* remove it from the lists */
514 list_del(&cifs_file->flist);
515 list_del(&cifs_file->tlist);
516 atomic_dec(&tcon->num_local_opens);
517
518 if (list_empty(&cifsi->openFileList)) {
519 cifs_dbg(FYI, "closing last open instance for inode %p\n",
520 d_inode(cifs_file->dentry));
521 /*
522 * In strict cache mode we need invalidate mapping on the last
523 * close because it may cause a error when we open this file
524 * again and get at least level II oplock.
525 */
526 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
527 set_bit(CIFS_INO_INVALID_MAPPING, &cifsi->flags);
528 cifs_set_oplock_level(cifsi, 0);
529 }
530
531 spin_unlock(&cifsi->open_file_lock);
532 spin_unlock(&tcon->open_file_lock);
533
534 oplock_break_cancelled = wait_oplock_handler ?
535 cancel_work_sync(&cifs_file->oplock_break) : false;
536
537 if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
538 struct TCP_Server_Info *server = tcon->ses->server;
539 unsigned int xid;
540
541 xid = get_xid();
542 if (server->ops->close_getattr)
543 server->ops->close_getattr(xid, tcon, cifs_file);
544 else if (server->ops->close)
545 server->ops->close(xid, tcon, &cifs_file->fid);
546 _free_xid(xid);
547 }
548
549 if (oplock_break_cancelled)
550 cifs_done_oplock_break(cifsi);
551
552 cifs_del_pending_open(&open);
553
554 if (offload)
555 queue_work(fileinfo_put_wq, &cifs_file->put);
556 else
557 cifsFileInfo_put_final(cifs_file);
558 }
559
cifs_open(struct inode * inode,struct file * file)560 int cifs_open(struct inode *inode, struct file *file)
561
562 {
563 int rc = -EACCES;
564 unsigned int xid;
565 __u32 oplock;
566 struct cifs_sb_info *cifs_sb;
567 struct TCP_Server_Info *server;
568 struct cifs_tcon *tcon;
569 struct tcon_link *tlink;
570 struct cifsFileInfo *cfile = NULL;
571 void *page;
572 const char *full_path;
573 bool posix_open_ok = false;
574 struct cifs_fid fid = {};
575 struct cifs_pending_open open;
576 struct cifs_open_info_data data = {};
577
578 xid = get_xid();
579
580 cifs_sb = CIFS_SB(inode->i_sb);
581 if (unlikely(cifs_forced_shutdown(cifs_sb))) {
582 free_xid(xid);
583 return -EIO;
584 }
585
586 tlink = cifs_sb_tlink(cifs_sb);
587 if (IS_ERR(tlink)) {
588 free_xid(xid);
589 return PTR_ERR(tlink);
590 }
591 tcon = tlink_tcon(tlink);
592 server = tcon->ses->server;
593
594 page = alloc_dentry_path();
595 full_path = build_path_from_dentry(file_dentry(file), page);
596 if (IS_ERR(full_path)) {
597 rc = PTR_ERR(full_path);
598 goto out;
599 }
600
601 cifs_dbg(FYI, "inode = 0x%p file flags are 0x%x for %s\n",
602 inode, file->f_flags, full_path);
603
604 if (file->f_flags & O_DIRECT &&
605 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
606 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
607 file->f_op = &cifs_file_direct_nobrl_ops;
608 else
609 file->f_op = &cifs_file_direct_ops;
610 }
611
612 /* Get the cached handle as SMB2 close is deferred */
613 rc = cifs_get_readable_path(tcon, full_path, &cfile);
614 if (rc == 0) {
615 if (file->f_flags == cfile->f_flags) {
616 file->private_data = cfile;
617 spin_lock(&CIFS_I(inode)->deferred_lock);
618 cifs_del_deferred_close(cfile);
619 spin_unlock(&CIFS_I(inode)->deferred_lock);
620 goto use_cache;
621 } else {
622 _cifsFileInfo_put(cfile, true, false);
623 }
624 }
625
626 if (server->oplocks)
627 oplock = REQ_OPLOCK;
628 else
629 oplock = 0;
630
631 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
632 if (!tcon->broken_posix_open && tcon->unix_ext &&
633 cap_unix(tcon->ses) && (CIFS_UNIX_POSIX_PATH_OPS_CAP &
634 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
635 /* can not refresh inode info since size could be stale */
636 rc = cifs_posix_open(full_path, &inode, inode->i_sb,
637 cifs_sb->ctx->file_mode /* ignored */,
638 file->f_flags, &oplock, &fid.netfid, xid);
639 if (rc == 0) {
640 cifs_dbg(FYI, "posix open succeeded\n");
641 posix_open_ok = true;
642 } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
643 if (tcon->ses->serverNOS)
644 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",
645 tcon->ses->ip_addr,
646 tcon->ses->serverNOS);
647 tcon->broken_posix_open = true;
648 } else if ((rc != -EIO) && (rc != -EREMOTE) &&
649 (rc != -EOPNOTSUPP)) /* path not found or net err */
650 goto out;
651 /*
652 * Else fallthrough to retry open the old way on network i/o
653 * or DFS errors.
654 */
655 }
656 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
657
658 if (server->ops->get_lease_key)
659 server->ops->get_lease_key(inode, &fid);
660
661 cifs_add_pending_open(&fid, tlink, &open);
662
663 if (!posix_open_ok) {
664 if (server->ops->get_lease_key)
665 server->ops->get_lease_key(inode, &fid);
666
667 rc = cifs_nt_open(full_path, inode, cifs_sb, tcon, file->f_flags, &oplock, &fid,
668 xid, &data);
669 if (rc) {
670 cifs_del_pending_open(&open);
671 goto out;
672 }
673 }
674
675 cfile = cifs_new_fileinfo(&fid, file, tlink, oplock, data.symlink_target);
676 if (cfile == NULL) {
677 if (server->ops->close)
678 server->ops->close(xid, tcon, &fid);
679 cifs_del_pending_open(&open);
680 rc = -ENOMEM;
681 goto out;
682 }
683
684 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
685 if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
686 /*
687 * Time to set mode which we can not set earlier due to
688 * problems creating new read-only files.
689 */
690 struct cifs_unix_set_info_args args = {
691 .mode = inode->i_mode,
692 .uid = INVALID_UID, /* no change */
693 .gid = INVALID_GID, /* no change */
694 .ctime = NO_CHANGE_64,
695 .atime = NO_CHANGE_64,
696 .mtime = NO_CHANGE_64,
697 .device = 0,
698 };
699 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid.netfid,
700 cfile->pid);
701 }
702 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
703
704 use_cache:
705 fscache_use_cookie(cifs_inode_cookie(file_inode(file)),
706 file->f_mode & FMODE_WRITE);
707 if (file->f_flags & O_DIRECT &&
708 (!((file->f_flags & O_ACCMODE) != O_RDONLY) ||
709 file->f_flags & O_APPEND))
710 cifs_invalidate_cache(file_inode(file),
711 FSCACHE_INVAL_DIO_WRITE);
712
713 out:
714 free_dentry_path(page);
715 free_xid(xid);
716 cifs_put_tlink(tlink);
717 cifs_free_open_info(&data);
718 return rc;
719 }
720
721 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
722 static int cifs_push_posix_locks(struct cifsFileInfo *cfile);
723 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
724
725 /*
726 * Try to reacquire byte range locks that were released when session
727 * to server was lost.
728 */
729 static int
cifs_relock_file(struct cifsFileInfo * cfile)730 cifs_relock_file(struct cifsFileInfo *cfile)
731 {
732 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
733 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
734 int rc = 0;
735 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
736 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
737 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
738
739 down_read_nested(&cinode->lock_sem, SINGLE_DEPTH_NESTING);
740 if (cinode->can_cache_brlcks) {
741 /* can cache locks - no need to relock */
742 up_read(&cinode->lock_sem);
743 return rc;
744 }
745
746 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
747 if (cap_unix(tcon->ses) &&
748 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
749 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
750 rc = cifs_push_posix_locks(cfile);
751 else
752 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
753 rc = tcon->ses->server->ops->push_mand_locks(cfile);
754
755 up_read(&cinode->lock_sem);
756 return rc;
757 }
758
759 static int
cifs_reopen_file(struct cifsFileInfo * cfile,bool can_flush)760 cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
761 {
762 int rc = -EACCES;
763 unsigned int xid;
764 __u32 oplock;
765 struct cifs_sb_info *cifs_sb;
766 struct cifs_tcon *tcon;
767 struct TCP_Server_Info *server;
768 struct cifsInodeInfo *cinode;
769 struct inode *inode;
770 void *page;
771 const char *full_path;
772 int desired_access;
773 int disposition = FILE_OPEN;
774 int create_options = CREATE_NOT_DIR;
775 struct cifs_open_parms oparms;
776
777 xid = get_xid();
778 mutex_lock(&cfile->fh_mutex);
779 if (!cfile->invalidHandle) {
780 mutex_unlock(&cfile->fh_mutex);
781 free_xid(xid);
782 return 0;
783 }
784
785 inode = d_inode(cfile->dentry);
786 cifs_sb = CIFS_SB(inode->i_sb);
787 tcon = tlink_tcon(cfile->tlink);
788 server = tcon->ses->server;
789
790 /*
791 * Can not grab rename sem here because various ops, including those
792 * that already have the rename sem can end up causing writepage to get
793 * called and if the server was down that means we end up here, and we
794 * can never tell if the caller already has the rename_sem.
795 */
796 page = alloc_dentry_path();
797 full_path = build_path_from_dentry(cfile->dentry, page);
798 if (IS_ERR(full_path)) {
799 mutex_unlock(&cfile->fh_mutex);
800 free_dentry_path(page);
801 free_xid(xid);
802 return PTR_ERR(full_path);
803 }
804
805 cifs_dbg(FYI, "inode = 0x%p file flags 0x%x for %s\n",
806 inode, cfile->f_flags, full_path);
807
808 if (tcon->ses->server->oplocks)
809 oplock = REQ_OPLOCK;
810 else
811 oplock = 0;
812
813 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
814 if (tcon->unix_ext && cap_unix(tcon->ses) &&
815 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
816 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
817 /*
818 * O_CREAT, O_EXCL and O_TRUNC already had their effect on the
819 * original open. Must mask them off for a reopen.
820 */
821 unsigned int oflags = cfile->f_flags &
822 ~(O_CREAT | O_EXCL | O_TRUNC);
823
824 rc = cifs_posix_open(full_path, NULL, inode->i_sb,
825 cifs_sb->ctx->file_mode /* ignored */,
826 oflags, &oplock, &cfile->fid.netfid, xid);
827 if (rc == 0) {
828 cifs_dbg(FYI, "posix reopen succeeded\n");
829 oparms.reconnect = true;
830 goto reopen_success;
831 }
832 /*
833 * fallthrough to retry open the old way on errors, especially
834 * in the reconnect path it is important to retry hard
835 */
836 }
837 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
838
839 desired_access = cifs_convert_flags(cfile->f_flags);
840
841 /* O_SYNC also has bit for O_DSYNC so following check picks up either */
842 if (cfile->f_flags & O_SYNC)
843 create_options |= CREATE_WRITE_THROUGH;
844
845 if (cfile->f_flags & O_DIRECT)
846 create_options |= CREATE_NO_BUFFER;
847
848 if (server->ops->get_lease_key)
849 server->ops->get_lease_key(inode, &cfile->fid);
850
851 oparms.tcon = tcon;
852 oparms.cifs_sb = cifs_sb;
853 oparms.desired_access = desired_access;
854 oparms.create_options = cifs_create_options(cifs_sb, create_options);
855 oparms.disposition = disposition;
856 oparms.path = full_path;
857 oparms.fid = &cfile->fid;
858 oparms.reconnect = true;
859
860 /*
861 * Can not refresh inode by passing in file_info buf to be returned by
862 * ops->open and then calling get_inode_info with returned buf since
863 * file might have write behind data that needs to be flushed and server
864 * version of file size can be stale. If we knew for sure that inode was
865 * not dirty locally we could do this.
866 */
867 rc = server->ops->open(xid, &oparms, &oplock, NULL);
868 if (rc == -ENOENT && oparms.reconnect == false) {
869 /* durable handle timeout is expired - open the file again */
870 rc = server->ops->open(xid, &oparms, &oplock, NULL);
871 /* indicate that we need to relock the file */
872 oparms.reconnect = true;
873 }
874
875 if (rc) {
876 mutex_unlock(&cfile->fh_mutex);
877 cifs_dbg(FYI, "cifs_reopen returned 0x%x\n", rc);
878 cifs_dbg(FYI, "oplock: %d\n", oplock);
879 goto reopen_error_exit;
880 }
881
882 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
883 reopen_success:
884 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
885 cfile->invalidHandle = false;
886 mutex_unlock(&cfile->fh_mutex);
887 cinode = CIFS_I(inode);
888
889 if (can_flush) {
890 rc = filemap_write_and_wait(inode->i_mapping);
891 if (!is_interrupt_error(rc))
892 mapping_set_error(inode->i_mapping, rc);
893
894 if (tcon->posix_extensions)
895 rc = smb311_posix_get_inode_info(&inode, full_path, inode->i_sb, xid);
896 else if (tcon->unix_ext)
897 rc = cifs_get_inode_info_unix(&inode, full_path,
898 inode->i_sb, xid);
899 else
900 rc = cifs_get_inode_info(&inode, full_path, NULL,
901 inode->i_sb, xid, NULL);
902 }
903 /*
904 * Else we are writing out data to server already and could deadlock if
905 * we tried to flush data, and since we do not know if we have data that
906 * would invalidate the current end of file on the server we can not go
907 * to the server to get the new inode info.
908 */
909
910 /*
911 * If the server returned a read oplock and we have mandatory brlocks,
912 * set oplock level to None.
913 */
914 if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
915 cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
916 oplock = 0;
917 }
918
919 server->ops->set_fid(cfile, &cfile->fid, oplock);
920 if (oparms.reconnect)
921 cifs_relock_file(cfile);
922
923 reopen_error_exit:
924 free_dentry_path(page);
925 free_xid(xid);
926 return rc;
927 }
928
smb2_deferred_work_close(struct work_struct * work)929 void smb2_deferred_work_close(struct work_struct *work)
930 {
931 struct cifsFileInfo *cfile = container_of(work,
932 struct cifsFileInfo, deferred.work);
933
934 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);
935 cifs_del_deferred_close(cfile);
936 cfile->deferred_close_scheduled = false;
937 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);
938 _cifsFileInfo_put(cfile, true, false);
939 }
940
cifs_close(struct inode * inode,struct file * file)941 int cifs_close(struct inode *inode, struct file *file)
942 {
943 struct cifsFileInfo *cfile;
944 struct cifsInodeInfo *cinode = CIFS_I(inode);
945 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
946 struct cifs_deferred_close *dclose;
947
948 cifs_fscache_unuse_inode_cookie(inode, file->f_mode & FMODE_WRITE);
949
950 if (file->private_data != NULL) {
951 cfile = file->private_data;
952 file->private_data = NULL;
953 dclose = kmalloc(sizeof(struct cifs_deferred_close), GFP_KERNEL);
954 if ((cinode->oplock == CIFS_CACHE_RHW_FLG) &&
955 cinode->lease_granted &&
956 !test_bit(CIFS_INO_CLOSE_ON_LOCK, &cinode->flags) &&
957 dclose) {
958 if (test_and_clear_bit(CIFS_INO_MODIFIED_ATTR, &cinode->flags)) {
959 inode->i_ctime = inode->i_mtime = current_time(inode);
960 }
961 spin_lock(&cinode->deferred_lock);
962 cifs_add_deferred_close(cfile, dclose);
963 if (cfile->deferred_close_scheduled &&
964 delayed_work_pending(&cfile->deferred)) {
965 /*
966 * If there is no pending work, mod_delayed_work queues new work.
967 * So, Increase the ref count to avoid use-after-free.
968 */
969 if (!mod_delayed_work(deferredclose_wq,
970 &cfile->deferred, cifs_sb->ctx->closetimeo))
971 cifsFileInfo_get(cfile);
972 } else {
973 /* Deferred close for files */
974 queue_delayed_work(deferredclose_wq,
975 &cfile->deferred, cifs_sb->ctx->closetimeo);
976 cfile->deferred_close_scheduled = true;
977 spin_unlock(&cinode->deferred_lock);
978 return 0;
979 }
980 spin_unlock(&cinode->deferred_lock);
981 _cifsFileInfo_put(cfile, true, false);
982 } else {
983 _cifsFileInfo_put(cfile, true, false);
984 kfree(dclose);
985 }
986 }
987
988 /* return code from the ->release op is always ignored */
989 return 0;
990 }
991
992 void
cifs_reopen_persistent_handles(struct cifs_tcon * tcon)993 cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
994 {
995 struct cifsFileInfo *open_file, *tmp;
996 struct list_head tmp_list;
997
998 if (!tcon->use_persistent || !tcon->need_reopen_files)
999 return;
1000
1001 tcon->need_reopen_files = false;
1002
1003 cifs_dbg(FYI, "Reopen persistent handles\n");
1004 INIT_LIST_HEAD(&tmp_list);
1005
1006 /* list all files open on tree connection, reopen resilient handles */
1007 spin_lock(&tcon->open_file_lock);
1008 list_for_each_entry(open_file, &tcon->openFileList, tlist) {
1009 if (!open_file->invalidHandle)
1010 continue;
1011 cifsFileInfo_get(open_file);
1012 list_add_tail(&open_file->rlist, &tmp_list);
1013 }
1014 spin_unlock(&tcon->open_file_lock);
1015
1016 list_for_each_entry_safe(open_file, tmp, &tmp_list, rlist) {
1017 if (cifs_reopen_file(open_file, false /* do not flush */))
1018 tcon->need_reopen_files = true;
1019 list_del_init(&open_file->rlist);
1020 cifsFileInfo_put(open_file);
1021 }
1022 }
1023
cifs_closedir(struct inode * inode,struct file * file)1024 int cifs_closedir(struct inode *inode, struct file *file)
1025 {
1026 int rc = 0;
1027 unsigned int xid;
1028 struct cifsFileInfo *cfile = file->private_data;
1029 struct cifs_tcon *tcon;
1030 struct TCP_Server_Info *server;
1031 char *buf;
1032
1033 cifs_dbg(FYI, "Closedir inode = 0x%p\n", inode);
1034
1035 if (cfile == NULL)
1036 return rc;
1037
1038 xid = get_xid();
1039 tcon = tlink_tcon(cfile->tlink);
1040 server = tcon->ses->server;
1041
1042 cifs_dbg(FYI, "Freeing private data in close dir\n");
1043 spin_lock(&cfile->file_info_lock);
1044 if (server->ops->dir_needs_close(cfile)) {
1045 cfile->invalidHandle = true;
1046 spin_unlock(&cfile->file_info_lock);
1047 if (server->ops->close_dir)
1048 rc = server->ops->close_dir(xid, tcon, &cfile->fid);
1049 else
1050 rc = -ENOSYS;
1051 cifs_dbg(FYI, "Closing uncompleted readdir with rc %d\n", rc);
1052 /* not much we can do if it fails anyway, ignore rc */
1053 rc = 0;
1054 } else
1055 spin_unlock(&cfile->file_info_lock);
1056
1057 buf = cfile->srch_inf.ntwrk_buf_start;
1058 if (buf) {
1059 cifs_dbg(FYI, "closedir free smb buf in srch struct\n");
1060 cfile->srch_inf.ntwrk_buf_start = NULL;
1061 if (cfile->srch_inf.smallBuf)
1062 cifs_small_buf_release(buf);
1063 else
1064 cifs_buf_release(buf);
1065 }
1066
1067 cifs_put_tlink(cfile->tlink);
1068 kfree(file->private_data);
1069 file->private_data = NULL;
1070 /* BB can we lock the filestruct while this is going on? */
1071 free_xid(xid);
1072 return rc;
1073 }
1074
1075 static struct cifsLockInfo *
cifs_lock_init(__u64 offset,__u64 length,__u8 type,__u16 flags)1076 cifs_lock_init(__u64 offset, __u64 length, __u8 type, __u16 flags)
1077 {
1078 struct cifsLockInfo *lock =
1079 kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
1080 if (!lock)
1081 return lock;
1082 lock->offset = offset;
1083 lock->length = length;
1084 lock->type = type;
1085 lock->pid = current->tgid;
1086 lock->flags = flags;
1087 INIT_LIST_HEAD(&lock->blist);
1088 init_waitqueue_head(&lock->block_q);
1089 return lock;
1090 }
1091
1092 void
cifs_del_lock_waiters(struct cifsLockInfo * lock)1093 cifs_del_lock_waiters(struct cifsLockInfo *lock)
1094 {
1095 struct cifsLockInfo *li, *tmp;
1096 list_for_each_entry_safe(li, tmp, &lock->blist, blist) {
1097 list_del_init(&li->blist);
1098 wake_up(&li->block_q);
1099 }
1100 }
1101
1102 #define CIFS_LOCK_OP 0
1103 #define CIFS_READ_OP 1
1104 #define CIFS_WRITE_OP 2
1105
1106 /* @rw_check : 0 - no op, 1 - read, 2 - write */
1107 static bool
cifs_find_fid_lock_conflict(struct cifs_fid_locks * fdlocks,__u64 offset,__u64 length,__u8 type,__u16 flags,struct cifsFileInfo * cfile,struct cifsLockInfo ** conf_lock,int rw_check)1108 cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
1109 __u64 length, __u8 type, __u16 flags,
1110 struct cifsFileInfo *cfile,
1111 struct cifsLockInfo **conf_lock, int rw_check)
1112 {
1113 struct cifsLockInfo *li;
1114 struct cifsFileInfo *cur_cfile = fdlocks->cfile;
1115 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
1116
1117 list_for_each_entry(li, &fdlocks->locks, llist) {
1118 if (offset + length <= li->offset ||
1119 offset >= li->offset + li->length)
1120 continue;
1121 if (rw_check != CIFS_LOCK_OP && current->tgid == li->pid &&
1122 server->ops->compare_fids(cfile, cur_cfile)) {
1123 /* shared lock prevents write op through the same fid */
1124 if (!(li->type & server->vals->shared_lock_type) ||
1125 rw_check != CIFS_WRITE_OP)
1126 continue;
1127 }
1128 if ((type & server->vals->shared_lock_type) &&
1129 ((server->ops->compare_fids(cfile, cur_cfile) &&
1130 current->tgid == li->pid) || type == li->type))
1131 continue;
1132 if (rw_check == CIFS_LOCK_OP &&
1133 (flags & FL_OFDLCK) && (li->flags & FL_OFDLCK) &&
1134 server->ops->compare_fids(cfile, cur_cfile))
1135 continue;
1136 if (conf_lock)
1137 *conf_lock = li;
1138 return true;
1139 }
1140 return false;
1141 }
1142
1143 bool
cifs_find_lock_conflict(struct cifsFileInfo * cfile,__u64 offset,__u64 length,__u8 type,__u16 flags,struct cifsLockInfo ** conf_lock,int rw_check)1144 cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
1145 __u8 type, __u16 flags,
1146 struct cifsLockInfo **conf_lock, int rw_check)
1147 {
1148 bool rc = false;
1149 struct cifs_fid_locks *cur;
1150 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1151
1152 list_for_each_entry(cur, &cinode->llist, llist) {
1153 rc = cifs_find_fid_lock_conflict(cur, offset, length, type,
1154 flags, cfile, conf_lock,
1155 rw_check);
1156 if (rc)
1157 break;
1158 }
1159
1160 return rc;
1161 }
1162
1163 /*
1164 * Check if there is another lock that prevents us to set the lock (mandatory
1165 * style). If such a lock exists, update the flock structure with its
1166 * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
1167 * or leave it the same if we can't. Returns 0 if we don't need to request to
1168 * the server or 1 otherwise.
1169 */
1170 static int
cifs_lock_test(struct cifsFileInfo * cfile,__u64 offset,__u64 length,__u8 type,struct file_lock * flock)1171 cifs_lock_test(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
1172 __u8 type, struct file_lock *flock)
1173 {
1174 int rc = 0;
1175 struct cifsLockInfo *conf_lock;
1176 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1177 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
1178 bool exist;
1179
1180 down_read(&cinode->lock_sem);
1181
1182 exist = cifs_find_lock_conflict(cfile, offset, length, type,
1183 flock->fl_flags, &conf_lock,
1184 CIFS_LOCK_OP);
1185 if (exist) {
1186 flock->fl_start = conf_lock->offset;
1187 flock->fl_end = conf_lock->offset + conf_lock->length - 1;
1188 flock->fl_pid = conf_lock->pid;
1189 if (conf_lock->type & server->vals->shared_lock_type)
1190 flock->fl_type = F_RDLCK;
1191 else
1192 flock->fl_type = F_WRLCK;
1193 } else if (!cinode->can_cache_brlcks)
1194 rc = 1;
1195 else
1196 flock->fl_type = F_UNLCK;
1197
1198 up_read(&cinode->lock_sem);
1199 return rc;
1200 }
1201
1202 static void
cifs_lock_add(struct cifsFileInfo * cfile,struct cifsLockInfo * lock)1203 cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock)
1204 {
1205 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1206 cifs_down_write(&cinode->lock_sem);
1207 list_add_tail(&lock->llist, &cfile->llist->locks);
1208 up_write(&cinode->lock_sem);
1209 }
1210
1211 /*
1212 * Set the byte-range lock (mandatory style). Returns:
1213 * 1) 0, if we set the lock and don't need to request to the server;
1214 * 2) 1, if no locks prevent us but we need to request to the server;
1215 * 3) -EACCES, if there is a lock that prevents us and wait is false.
1216 */
1217 static int
cifs_lock_add_if(struct cifsFileInfo * cfile,struct cifsLockInfo * lock,bool wait)1218 cifs_lock_add_if(struct cifsFileInfo *cfile, struct cifsLockInfo *lock,
1219 bool wait)
1220 {
1221 struct cifsLockInfo *conf_lock;
1222 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1223 bool exist;
1224 int rc = 0;
1225
1226 try_again:
1227 exist = false;
1228 cifs_down_write(&cinode->lock_sem);
1229
1230 exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length,
1231 lock->type, lock->flags, &conf_lock,
1232 CIFS_LOCK_OP);
1233 if (!exist && cinode->can_cache_brlcks) {
1234 list_add_tail(&lock->llist, &cfile->llist->locks);
1235 up_write(&cinode->lock_sem);
1236 return rc;
1237 }
1238
1239 if (!exist)
1240 rc = 1;
1241 else if (!wait)
1242 rc = -EACCES;
1243 else {
1244 list_add_tail(&lock->blist, &conf_lock->blist);
1245 up_write(&cinode->lock_sem);
1246 rc = wait_event_interruptible(lock->block_q,
1247 (lock->blist.prev == &lock->blist) &&
1248 (lock->blist.next == &lock->blist));
1249 if (!rc)
1250 goto try_again;
1251 cifs_down_write(&cinode->lock_sem);
1252 list_del_init(&lock->blist);
1253 }
1254
1255 up_write(&cinode->lock_sem);
1256 return rc;
1257 }
1258
1259 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1260 /*
1261 * Check if there is another lock that prevents us to set the lock (posix
1262 * style). If such a lock exists, update the flock structure with its
1263 * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
1264 * or leave it the same if we can't. Returns 0 if we don't need to request to
1265 * the server or 1 otherwise.
1266 */
1267 static int
cifs_posix_lock_test(struct file * file,struct file_lock * flock)1268 cifs_posix_lock_test(struct file *file, struct file_lock *flock)
1269 {
1270 int rc = 0;
1271 struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
1272 unsigned char saved_type = flock->fl_type;
1273
1274 if ((flock->fl_flags & FL_POSIX) == 0)
1275 return 1;
1276
1277 down_read(&cinode->lock_sem);
1278 posix_test_lock(file, flock);
1279
1280 if (flock->fl_type == F_UNLCK && !cinode->can_cache_brlcks) {
1281 flock->fl_type = saved_type;
1282 rc = 1;
1283 }
1284
1285 up_read(&cinode->lock_sem);
1286 return rc;
1287 }
1288
1289 /*
1290 * Set the byte-range lock (posix style). Returns:
1291 * 1) <0, if the error occurs while setting the lock;
1292 * 2) 0, if we set the lock and don't need to request to the server;
1293 * 3) FILE_LOCK_DEFERRED, if we will wait for some other file_lock;
1294 * 4) FILE_LOCK_DEFERRED + 1, if we need to request to the server.
1295 */
1296 static int
cifs_posix_lock_set(struct file * file,struct file_lock * flock)1297 cifs_posix_lock_set(struct file *file, struct file_lock *flock)
1298 {
1299 struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
1300 int rc = FILE_LOCK_DEFERRED + 1;
1301
1302 if ((flock->fl_flags & FL_POSIX) == 0)
1303 return rc;
1304
1305 cifs_down_write(&cinode->lock_sem);
1306 if (!cinode->can_cache_brlcks) {
1307 up_write(&cinode->lock_sem);
1308 return rc;
1309 }
1310
1311 rc = posix_lock_file(file, flock, NULL);
1312 up_write(&cinode->lock_sem);
1313 return rc;
1314 }
1315
1316 int
cifs_push_mandatory_locks(struct cifsFileInfo * cfile)1317 cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
1318 {
1319 unsigned int xid;
1320 int rc = 0, stored_rc;
1321 struct cifsLockInfo *li, *tmp;
1322 struct cifs_tcon *tcon;
1323 unsigned int num, max_num, max_buf;
1324 LOCKING_ANDX_RANGE *buf, *cur;
1325 static const int types[] = {
1326 LOCKING_ANDX_LARGE_FILES,
1327 LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES
1328 };
1329 int i;
1330
1331 xid = get_xid();
1332 tcon = tlink_tcon(cfile->tlink);
1333
1334 /*
1335 * Accessing maxBuf is racy with cifs_reconnect - need to store value
1336 * and check it before using.
1337 */
1338 max_buf = tcon->ses->server->maxBuf;
1339 if (max_buf < (sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE))) {
1340 free_xid(xid);
1341 return -EINVAL;
1342 }
1343
1344 BUILD_BUG_ON(sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE) >
1345 PAGE_SIZE);
1346 max_buf = min_t(unsigned int, max_buf - sizeof(struct smb_hdr),
1347 PAGE_SIZE);
1348 max_num = (max_buf - sizeof(struct smb_hdr)) /
1349 sizeof(LOCKING_ANDX_RANGE);
1350 buf = kcalloc(max_num, sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
1351 if (!buf) {
1352 free_xid(xid);
1353 return -ENOMEM;
1354 }
1355
1356 for (i = 0; i < 2; i++) {
1357 cur = buf;
1358 num = 0;
1359 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
1360 if (li->type != types[i])
1361 continue;
1362 cur->Pid = cpu_to_le16(li->pid);
1363 cur->LengthLow = cpu_to_le32((u32)li->length);
1364 cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
1365 cur->OffsetLow = cpu_to_le32((u32)li->offset);
1366 cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
1367 if (++num == max_num) {
1368 stored_rc = cifs_lockv(xid, tcon,
1369 cfile->fid.netfid,
1370 (__u8)li->type, 0, num,
1371 buf);
1372 if (stored_rc)
1373 rc = stored_rc;
1374 cur = buf;
1375 num = 0;
1376 } else
1377 cur++;
1378 }
1379
1380 if (num) {
1381 stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
1382 (__u8)types[i], 0, num, buf);
1383 if (stored_rc)
1384 rc = stored_rc;
1385 }
1386 }
1387
1388 kfree(buf);
1389 free_xid(xid);
1390 return rc;
1391 }
1392
1393 static __u32
hash_lockowner(fl_owner_t owner)1394 hash_lockowner(fl_owner_t owner)
1395 {
1396 return cifs_lock_secret ^ hash32_ptr((const void *)owner);
1397 }
1398 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1399
1400 struct lock_to_push {
1401 struct list_head llist;
1402 __u64 offset;
1403 __u64 length;
1404 __u32 pid;
1405 __u16 netfid;
1406 __u8 type;
1407 };
1408
1409 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1410 static int
cifs_push_posix_locks(struct cifsFileInfo * cfile)1411 cifs_push_posix_locks(struct cifsFileInfo *cfile)
1412 {
1413 struct inode *inode = d_inode(cfile->dentry);
1414 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1415 struct file_lock *flock;
1416 struct file_lock_context *flctx = inode->i_flctx;
1417 unsigned int count = 0, i;
1418 int rc = 0, xid, type;
1419 struct list_head locks_to_send, *el;
1420 struct lock_to_push *lck, *tmp;
1421 __u64 length;
1422
1423 xid = get_xid();
1424
1425 if (!flctx)
1426 goto out;
1427
1428 spin_lock(&flctx->flc_lock);
1429 list_for_each(el, &flctx->flc_posix) {
1430 count++;
1431 }
1432 spin_unlock(&flctx->flc_lock);
1433
1434 INIT_LIST_HEAD(&locks_to_send);
1435
1436 /*
1437 * Allocating count locks is enough because no FL_POSIX locks can be
1438 * added to the list while we are holding cinode->lock_sem that
1439 * protects locking operations of this inode.
1440 */
1441 for (i = 0; i < count; i++) {
1442 lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
1443 if (!lck) {
1444 rc = -ENOMEM;
1445 goto err_out;
1446 }
1447 list_add_tail(&lck->llist, &locks_to_send);
1448 }
1449
1450 el = locks_to_send.next;
1451 spin_lock(&flctx->flc_lock);
1452 list_for_each_entry(flock, &flctx->flc_posix, fl_list) {
1453 if (el == &locks_to_send) {
1454 /*
1455 * The list ended. We don't have enough allocated
1456 * structures - something is really wrong.
1457 */
1458 cifs_dbg(VFS, "Can't push all brlocks!\n");
1459 break;
1460 }
1461 length = cifs_flock_len(flock);
1462 if (flock->fl_type == F_RDLCK || flock->fl_type == F_SHLCK)
1463 type = CIFS_RDLCK;
1464 else
1465 type = CIFS_WRLCK;
1466 lck = list_entry(el, struct lock_to_push, llist);
1467 lck->pid = hash_lockowner(flock->fl_owner);
1468 lck->netfid = cfile->fid.netfid;
1469 lck->length = length;
1470 lck->type = type;
1471 lck->offset = flock->fl_start;
1472 }
1473 spin_unlock(&flctx->flc_lock);
1474
1475 list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
1476 int stored_rc;
1477
1478 stored_rc = CIFSSMBPosixLock(xid, tcon, lck->netfid, lck->pid,
1479 lck->offset, lck->length, NULL,
1480 lck->type, 0);
1481 if (stored_rc)
1482 rc = stored_rc;
1483 list_del(&lck->llist);
1484 kfree(lck);
1485 }
1486
1487 out:
1488 free_xid(xid);
1489 return rc;
1490 err_out:
1491 list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
1492 list_del(&lck->llist);
1493 kfree(lck);
1494 }
1495 goto out;
1496 }
1497 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1498
1499 static int
cifs_push_locks(struct cifsFileInfo * cfile)1500 cifs_push_locks(struct cifsFileInfo *cfile)
1501 {
1502 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1503 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1504 int rc = 0;
1505 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1506 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
1507 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1508
1509 /* we are going to update can_cache_brlcks here - need a write access */
1510 cifs_down_write(&cinode->lock_sem);
1511 if (!cinode->can_cache_brlcks) {
1512 up_write(&cinode->lock_sem);
1513 return rc;
1514 }
1515
1516 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1517 if (cap_unix(tcon->ses) &&
1518 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1519 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1520 rc = cifs_push_posix_locks(cfile);
1521 else
1522 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1523 rc = tcon->ses->server->ops->push_mand_locks(cfile);
1524
1525 cinode->can_cache_brlcks = false;
1526 up_write(&cinode->lock_sem);
1527 return rc;
1528 }
1529
1530 static void
cifs_read_flock(struct file_lock * flock,__u32 * type,int * lock,int * unlock,bool * wait_flag,struct TCP_Server_Info * server)1531 cifs_read_flock(struct file_lock *flock, __u32 *type, int *lock, int *unlock,
1532 bool *wait_flag, struct TCP_Server_Info *server)
1533 {
1534 if (flock->fl_flags & FL_POSIX)
1535 cifs_dbg(FYI, "Posix\n");
1536 if (flock->fl_flags & FL_FLOCK)
1537 cifs_dbg(FYI, "Flock\n");
1538 if (flock->fl_flags & FL_SLEEP) {
1539 cifs_dbg(FYI, "Blocking lock\n");
1540 *wait_flag = true;
1541 }
1542 if (flock->fl_flags & FL_ACCESS)
1543 cifs_dbg(FYI, "Process suspended by mandatory locking - not implemented yet\n");
1544 if (flock->fl_flags & FL_LEASE)
1545 cifs_dbg(FYI, "Lease on file - not implemented yet\n");
1546 if (flock->fl_flags &
1547 (~(FL_POSIX | FL_FLOCK | FL_SLEEP |
1548 FL_ACCESS | FL_LEASE | FL_CLOSE | FL_OFDLCK)))
1549 cifs_dbg(FYI, "Unknown lock flags 0x%x\n", flock->fl_flags);
1550
1551 *type = server->vals->large_lock_type;
1552 if (flock->fl_type == F_WRLCK) {
1553 cifs_dbg(FYI, "F_WRLCK\n");
1554 *type |= server->vals->exclusive_lock_type;
1555 *lock = 1;
1556 } else if (flock->fl_type == F_UNLCK) {
1557 cifs_dbg(FYI, "F_UNLCK\n");
1558 *type |= server->vals->unlock_lock_type;
1559 *unlock = 1;
1560 /* Check if unlock includes more than one lock range */
1561 } else if (flock->fl_type == F_RDLCK) {
1562 cifs_dbg(FYI, "F_RDLCK\n");
1563 *type |= server->vals->shared_lock_type;
1564 *lock = 1;
1565 } else if (flock->fl_type == F_EXLCK) {
1566 cifs_dbg(FYI, "F_EXLCK\n");
1567 *type |= server->vals->exclusive_lock_type;
1568 *lock = 1;
1569 } else if (flock->fl_type == F_SHLCK) {
1570 cifs_dbg(FYI, "F_SHLCK\n");
1571 *type |= server->vals->shared_lock_type;
1572 *lock = 1;
1573 } else
1574 cifs_dbg(FYI, "Unknown type of lock\n");
1575 }
1576
1577 static int
cifs_getlk(struct file * file,struct file_lock * flock,__u32 type,bool wait_flag,bool posix_lck,unsigned int xid)1578 cifs_getlk(struct file *file, struct file_lock *flock, __u32 type,
1579 bool wait_flag, bool posix_lck, unsigned int xid)
1580 {
1581 int rc = 0;
1582 __u64 length = cifs_flock_len(flock);
1583 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
1584 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1585 struct TCP_Server_Info *server = tcon->ses->server;
1586 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1587 __u16 netfid = cfile->fid.netfid;
1588
1589 if (posix_lck) {
1590 int posix_lock_type;
1591
1592 rc = cifs_posix_lock_test(file, flock);
1593 if (!rc)
1594 return rc;
1595
1596 if (type & server->vals->shared_lock_type)
1597 posix_lock_type = CIFS_RDLCK;
1598 else
1599 posix_lock_type = CIFS_WRLCK;
1600 rc = CIFSSMBPosixLock(xid, tcon, netfid,
1601 hash_lockowner(flock->fl_owner),
1602 flock->fl_start, length, flock,
1603 posix_lock_type, wait_flag);
1604 return rc;
1605 }
1606 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1607
1608 rc = cifs_lock_test(cfile, flock->fl_start, length, type, flock);
1609 if (!rc)
1610 return rc;
1611
1612 /* BB we could chain these into one lock request BB */
1613 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length, type,
1614 1, 0, false);
1615 if (rc == 0) {
1616 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1617 type, 0, 1, false);
1618 flock->fl_type = F_UNLCK;
1619 if (rc != 0)
1620 cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
1621 rc);
1622 return 0;
1623 }
1624
1625 if (type & server->vals->shared_lock_type) {
1626 flock->fl_type = F_WRLCK;
1627 return 0;
1628 }
1629
1630 type &= ~server->vals->exclusive_lock_type;
1631
1632 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1633 type | server->vals->shared_lock_type,
1634 1, 0, false);
1635 if (rc == 0) {
1636 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1637 type | server->vals->shared_lock_type, 0, 1, false);
1638 flock->fl_type = F_RDLCK;
1639 if (rc != 0)
1640 cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
1641 rc);
1642 } else
1643 flock->fl_type = F_WRLCK;
1644
1645 return 0;
1646 }
1647
1648 void
cifs_move_llist(struct list_head * source,struct list_head * dest)1649 cifs_move_llist(struct list_head *source, struct list_head *dest)
1650 {
1651 struct list_head *li, *tmp;
1652 list_for_each_safe(li, tmp, source)
1653 list_move(li, dest);
1654 }
1655
1656 void
cifs_free_llist(struct list_head * llist)1657 cifs_free_llist(struct list_head *llist)
1658 {
1659 struct cifsLockInfo *li, *tmp;
1660 list_for_each_entry_safe(li, tmp, llist, llist) {
1661 cifs_del_lock_waiters(li);
1662 list_del(&li->llist);
1663 kfree(li);
1664 }
1665 }
1666
1667 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1668 int
cifs_unlock_range(struct cifsFileInfo * cfile,struct file_lock * flock,unsigned int xid)1669 cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
1670 unsigned int xid)
1671 {
1672 int rc = 0, stored_rc;
1673 static const int types[] = {
1674 LOCKING_ANDX_LARGE_FILES,
1675 LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES
1676 };
1677 unsigned int i;
1678 unsigned int max_num, num, max_buf;
1679 LOCKING_ANDX_RANGE *buf, *cur;
1680 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1681 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
1682 struct cifsLockInfo *li, *tmp;
1683 __u64 length = cifs_flock_len(flock);
1684 struct list_head tmp_llist;
1685
1686 INIT_LIST_HEAD(&tmp_llist);
1687
1688 /*
1689 * Accessing maxBuf is racy with cifs_reconnect - need to store value
1690 * and check it before using.
1691 */
1692 max_buf = tcon->ses->server->maxBuf;
1693 if (max_buf < (sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE)))
1694 return -EINVAL;
1695
1696 BUILD_BUG_ON(sizeof(struct smb_hdr) + sizeof(LOCKING_ANDX_RANGE) >
1697 PAGE_SIZE);
1698 max_buf = min_t(unsigned int, max_buf - sizeof(struct smb_hdr),
1699 PAGE_SIZE);
1700 max_num = (max_buf - sizeof(struct smb_hdr)) /
1701 sizeof(LOCKING_ANDX_RANGE);
1702 buf = kcalloc(max_num, sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
1703 if (!buf)
1704 return -ENOMEM;
1705
1706 cifs_down_write(&cinode->lock_sem);
1707 for (i = 0; i < 2; i++) {
1708 cur = buf;
1709 num = 0;
1710 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
1711 if (flock->fl_start > li->offset ||
1712 (flock->fl_start + length) <
1713 (li->offset + li->length))
1714 continue;
1715 if (current->tgid != li->pid)
1716 continue;
1717 if (types[i] != li->type)
1718 continue;
1719 if (cinode->can_cache_brlcks) {
1720 /*
1721 * We can cache brlock requests - simply remove
1722 * a lock from the file's list.
1723 */
1724 list_del(&li->llist);
1725 cifs_del_lock_waiters(li);
1726 kfree(li);
1727 continue;
1728 }
1729 cur->Pid = cpu_to_le16(li->pid);
1730 cur->LengthLow = cpu_to_le32((u32)li->length);
1731 cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
1732 cur->OffsetLow = cpu_to_le32((u32)li->offset);
1733 cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
1734 /*
1735 * We need to save a lock here to let us add it again to
1736 * the file's list if the unlock range request fails on
1737 * the server.
1738 */
1739 list_move(&li->llist, &tmp_llist);
1740 if (++num == max_num) {
1741 stored_rc = cifs_lockv(xid, tcon,
1742 cfile->fid.netfid,
1743 li->type, num, 0, buf);
1744 if (stored_rc) {
1745 /*
1746 * We failed on the unlock range
1747 * request - add all locks from the tmp
1748 * list to the head of the file's list.
1749 */
1750 cifs_move_llist(&tmp_llist,
1751 &cfile->llist->locks);
1752 rc = stored_rc;
1753 } else
1754 /*
1755 * The unlock range request succeed -
1756 * free the tmp list.
1757 */
1758 cifs_free_llist(&tmp_llist);
1759 cur = buf;
1760 num = 0;
1761 } else
1762 cur++;
1763 }
1764 if (num) {
1765 stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
1766 types[i], num, 0, buf);
1767 if (stored_rc) {
1768 cifs_move_llist(&tmp_llist,
1769 &cfile->llist->locks);
1770 rc = stored_rc;
1771 } else
1772 cifs_free_llist(&tmp_llist);
1773 }
1774 }
1775
1776 up_write(&cinode->lock_sem);
1777 kfree(buf);
1778 return rc;
1779 }
1780 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1781
1782 static int
cifs_setlk(struct file * file,struct file_lock * flock,__u32 type,bool wait_flag,bool posix_lck,int lock,int unlock,unsigned int xid)1783 cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
1784 bool wait_flag, bool posix_lck, int lock, int unlock,
1785 unsigned int xid)
1786 {
1787 int rc = 0;
1788 __u64 length = cifs_flock_len(flock);
1789 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
1790 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
1791 struct TCP_Server_Info *server = tcon->ses->server;
1792 struct inode *inode = d_inode(cfile->dentry);
1793
1794 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1795 if (posix_lck) {
1796 int posix_lock_type;
1797
1798 rc = cifs_posix_lock_set(file, flock);
1799 if (rc <= FILE_LOCK_DEFERRED)
1800 return rc;
1801
1802 if (type & server->vals->shared_lock_type)
1803 posix_lock_type = CIFS_RDLCK;
1804 else
1805 posix_lock_type = CIFS_WRLCK;
1806
1807 if (unlock == 1)
1808 posix_lock_type = CIFS_UNLCK;
1809
1810 rc = CIFSSMBPosixLock(xid, tcon, cfile->fid.netfid,
1811 hash_lockowner(flock->fl_owner),
1812 flock->fl_start, length,
1813 NULL, posix_lock_type, wait_flag);
1814 goto out;
1815 }
1816 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1817 if (lock) {
1818 struct cifsLockInfo *lock;
1819
1820 lock = cifs_lock_init(flock->fl_start, length, type,
1821 flock->fl_flags);
1822 if (!lock)
1823 return -ENOMEM;
1824
1825 rc = cifs_lock_add_if(cfile, lock, wait_flag);
1826 if (rc < 0) {
1827 kfree(lock);
1828 return rc;
1829 }
1830 if (!rc)
1831 goto out;
1832
1833 /*
1834 * Windows 7 server can delay breaking lease from read to None
1835 * if we set a byte-range lock on a file - break it explicitly
1836 * before sending the lock to the server to be sure the next
1837 * read won't conflict with non-overlapted locks due to
1838 * pagereading.
1839 */
1840 if (!CIFS_CACHE_WRITE(CIFS_I(inode)) &&
1841 CIFS_CACHE_READ(CIFS_I(inode))) {
1842 cifs_zap_mapping(inode);
1843 cifs_dbg(FYI, "Set no oplock for inode=%p due to mand locks\n",
1844 inode);
1845 CIFS_I(inode)->oplock = 0;
1846 }
1847
1848 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
1849 type, 1, 0, wait_flag);
1850 if (rc) {
1851 kfree(lock);
1852 return rc;
1853 }
1854
1855 cifs_lock_add(cfile, lock);
1856 } else if (unlock)
1857 rc = server->ops->mand_unlock_range(cfile, flock, xid);
1858
1859 out:
1860 if ((flock->fl_flags & FL_POSIX) || (flock->fl_flags & FL_FLOCK)) {
1861 /*
1862 * If this is a request to remove all locks because we
1863 * are closing the file, it doesn't matter if the
1864 * unlocking failed as both cifs.ko and the SMB server
1865 * remove the lock on file close
1866 */
1867 if (rc) {
1868 cifs_dbg(VFS, "%s failed rc=%d\n", __func__, rc);
1869 if (!(flock->fl_flags & FL_CLOSE))
1870 return rc;
1871 }
1872 rc = locks_lock_file_wait(file, flock);
1873 }
1874 return rc;
1875 }
1876
cifs_flock(struct file * file,int cmd,struct file_lock * fl)1877 int cifs_flock(struct file *file, int cmd, struct file_lock *fl)
1878 {
1879 int rc, xid;
1880 int lock = 0, unlock = 0;
1881 bool wait_flag = false;
1882 bool posix_lck = false;
1883 struct cifs_sb_info *cifs_sb;
1884 struct cifs_tcon *tcon;
1885 struct cifsFileInfo *cfile;
1886 __u32 type;
1887
1888 xid = get_xid();
1889
1890 if (!(fl->fl_flags & FL_FLOCK)) {
1891 rc = -ENOLCK;
1892 free_xid(xid);
1893 return rc;
1894 }
1895
1896 cfile = (struct cifsFileInfo *)file->private_data;
1897 tcon = tlink_tcon(cfile->tlink);
1898
1899 cifs_read_flock(fl, &type, &lock, &unlock, &wait_flag,
1900 tcon->ses->server);
1901 cifs_sb = CIFS_FILE_SB(file);
1902
1903 if (cap_unix(tcon->ses) &&
1904 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1905 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1906 posix_lck = true;
1907
1908 if (!lock && !unlock) {
1909 /*
1910 * if no lock or unlock then nothing to do since we do not
1911 * know what it is
1912 */
1913 rc = -EOPNOTSUPP;
1914 free_xid(xid);
1915 return rc;
1916 }
1917
1918 rc = cifs_setlk(file, fl, type, wait_flag, posix_lck, lock, unlock,
1919 xid);
1920 free_xid(xid);
1921 return rc;
1922
1923
1924 }
1925
cifs_lock(struct file * file,int cmd,struct file_lock * flock)1926 int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
1927 {
1928 int rc, xid;
1929 int lock = 0, unlock = 0;
1930 bool wait_flag = false;
1931 bool posix_lck = false;
1932 struct cifs_sb_info *cifs_sb;
1933 struct cifs_tcon *tcon;
1934 struct cifsFileInfo *cfile;
1935 __u32 type;
1936
1937 rc = -EACCES;
1938 xid = get_xid();
1939
1940 cifs_dbg(FYI, "%s: %pD2 cmd=0x%x type=0x%x flags=0x%x r=%lld:%lld\n", __func__, file, cmd,
1941 flock->fl_flags, flock->fl_type, (long long)flock->fl_start,
1942 (long long)flock->fl_end);
1943
1944 cfile = (struct cifsFileInfo *)file->private_data;
1945 tcon = tlink_tcon(cfile->tlink);
1946
1947 cifs_read_flock(flock, &type, &lock, &unlock, &wait_flag,
1948 tcon->ses->server);
1949 cifs_sb = CIFS_FILE_SB(file);
1950 set_bit(CIFS_INO_CLOSE_ON_LOCK, &CIFS_I(d_inode(cfile->dentry))->flags);
1951
1952 if (cap_unix(tcon->ses) &&
1953 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
1954 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
1955 posix_lck = true;
1956 /*
1957 * BB add code here to normalize offset and length to account for
1958 * negative length which we can not accept over the wire.
1959 */
1960 if (IS_GETLK(cmd)) {
1961 rc = cifs_getlk(file, flock, type, wait_flag, posix_lck, xid);
1962 free_xid(xid);
1963 return rc;
1964 }
1965
1966 if (!lock && !unlock) {
1967 /*
1968 * if no lock or unlock then nothing to do since we do not
1969 * know what it is
1970 */
1971 free_xid(xid);
1972 return -EOPNOTSUPP;
1973 }
1974
1975 rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock,
1976 xid);
1977 free_xid(xid);
1978 return rc;
1979 }
1980
1981 /*
1982 * update the file size (if needed) after a write. Should be called with
1983 * the inode->i_lock held
1984 */
1985 void
cifs_update_eof(struct cifsInodeInfo * cifsi,loff_t offset,unsigned int bytes_written)1986 cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
1987 unsigned int bytes_written)
1988 {
1989 loff_t end_of_write = offset + bytes_written;
1990
1991 if (end_of_write > cifsi->server_eof)
1992 cifsi->server_eof = end_of_write;
1993 }
1994
1995 static ssize_t
cifs_write(struct cifsFileInfo * open_file,__u32 pid,const char * write_data,size_t write_size,loff_t * offset)1996 cifs_write(struct cifsFileInfo *open_file, __u32 pid, const char *write_data,
1997 size_t write_size, loff_t *offset)
1998 {
1999 int rc = 0;
2000 unsigned int bytes_written = 0;
2001 unsigned int total_written;
2002 struct cifs_tcon *tcon;
2003 struct TCP_Server_Info *server;
2004 unsigned int xid;
2005 struct dentry *dentry = open_file->dentry;
2006 struct cifsInodeInfo *cifsi = CIFS_I(d_inode(dentry));
2007 struct cifs_io_parms io_parms = {0};
2008
2009 cifs_dbg(FYI, "write %zd bytes to offset %lld of %pd\n",
2010 write_size, *offset, dentry);
2011
2012 tcon = tlink_tcon(open_file->tlink);
2013 server = tcon->ses->server;
2014
2015 if (!server->ops->sync_write)
2016 return -ENOSYS;
2017
2018 xid = get_xid();
2019
2020 for (total_written = 0; write_size > total_written;
2021 total_written += bytes_written) {
2022 rc = -EAGAIN;
2023 while (rc == -EAGAIN) {
2024 struct kvec iov[2];
2025 unsigned int len;
2026
2027 if (open_file->invalidHandle) {
2028 /* we could deadlock if we called
2029 filemap_fdatawait from here so tell
2030 reopen_file not to flush data to
2031 server now */
2032 rc = cifs_reopen_file(open_file, false);
2033 if (rc != 0)
2034 break;
2035 }
2036
2037 len = min(server->ops->wp_retry_size(d_inode(dentry)),
2038 (unsigned int)write_size - total_written);
2039 /* iov[0] is reserved for smb header */
2040 iov[1].iov_base = (char *)write_data + total_written;
2041 iov[1].iov_len = len;
2042 io_parms.pid = pid;
2043 io_parms.tcon = tcon;
2044 io_parms.offset = *offset;
2045 io_parms.length = len;
2046 rc = server->ops->sync_write(xid, &open_file->fid,
2047 &io_parms, &bytes_written, iov, 1);
2048 }
2049 if (rc || (bytes_written == 0)) {
2050 if (total_written)
2051 break;
2052 else {
2053 free_xid(xid);
2054 return rc;
2055 }
2056 } else {
2057 spin_lock(&d_inode(dentry)->i_lock);
2058 cifs_update_eof(cifsi, *offset, bytes_written);
2059 spin_unlock(&d_inode(dentry)->i_lock);
2060 *offset += bytes_written;
2061 }
2062 }
2063
2064 cifs_stats_bytes_written(tcon, total_written);
2065
2066 if (total_written > 0) {
2067 spin_lock(&d_inode(dentry)->i_lock);
2068 if (*offset > d_inode(dentry)->i_size) {
2069 i_size_write(d_inode(dentry), *offset);
2070 d_inode(dentry)->i_blocks = (512 - 1 + *offset) >> 9;
2071 }
2072 spin_unlock(&d_inode(dentry)->i_lock);
2073 }
2074 mark_inode_dirty_sync(d_inode(dentry));
2075 free_xid(xid);
2076 return total_written;
2077 }
2078
find_readable_file(struct cifsInodeInfo * cifs_inode,bool fsuid_only)2079 struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
2080 bool fsuid_only)
2081 {
2082 struct cifsFileInfo *open_file = NULL;
2083 struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->netfs.inode.i_sb);
2084
2085 /* only filter by fsuid on multiuser mounts */
2086 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
2087 fsuid_only = false;
2088
2089 spin_lock(&cifs_inode->open_file_lock);
2090 /* we could simply get the first_list_entry since write-only entries
2091 are always at the end of the list but since the first entry might
2092 have a close pending, we go through the whole list */
2093 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
2094 if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
2095 continue;
2096 if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
2097 if ((!open_file->invalidHandle)) {
2098 /* found a good file */
2099 /* lock it so it will not be closed on us */
2100 cifsFileInfo_get(open_file);
2101 spin_unlock(&cifs_inode->open_file_lock);
2102 return open_file;
2103 } /* else might as well continue, and look for
2104 another, or simply have the caller reopen it
2105 again rather than trying to fix this handle */
2106 } else /* write only file */
2107 break; /* write only files are last so must be done */
2108 }
2109 spin_unlock(&cifs_inode->open_file_lock);
2110 return NULL;
2111 }
2112
2113 /* Return -EBADF if no handle is found and general rc otherwise */
2114 int
cifs_get_writable_file(struct cifsInodeInfo * cifs_inode,int flags,struct cifsFileInfo ** ret_file)2115 cifs_get_writable_file(struct cifsInodeInfo *cifs_inode, int flags,
2116 struct cifsFileInfo **ret_file)
2117 {
2118 struct cifsFileInfo *open_file, *inv_file = NULL;
2119 struct cifs_sb_info *cifs_sb;
2120 bool any_available = false;
2121 int rc = -EBADF;
2122 unsigned int refind = 0;
2123 bool fsuid_only = flags & FIND_WR_FSUID_ONLY;
2124 bool with_delete = flags & FIND_WR_WITH_DELETE;
2125 *ret_file = NULL;
2126
2127 /*
2128 * Having a null inode here (because mapping->host was set to zero by
2129 * the VFS or MM) should not happen but we had reports of on oops (due
2130 * to it being zero) during stress testcases so we need to check for it
2131 */
2132
2133 if (cifs_inode == NULL) {
2134 cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");
2135 dump_stack();
2136 return rc;
2137 }
2138
2139 cifs_sb = CIFS_SB(cifs_inode->netfs.inode.i_sb);
2140
2141 /* only filter by fsuid on multiuser mounts */
2142 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
2143 fsuid_only = false;
2144
2145 spin_lock(&cifs_inode->open_file_lock);
2146 refind_writable:
2147 if (refind > MAX_REOPEN_ATT) {
2148 spin_unlock(&cifs_inode->open_file_lock);
2149 return rc;
2150 }
2151 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
2152 if (!any_available && open_file->pid != current->tgid)
2153 continue;
2154 if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
2155 continue;
2156 if (with_delete && !(open_file->fid.access & DELETE))
2157 continue;
2158 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
2159 if (!open_file->invalidHandle) {
2160 /* found a good writable file */
2161 cifsFileInfo_get(open_file);
2162 spin_unlock(&cifs_inode->open_file_lock);
2163 *ret_file = open_file;
2164 return 0;
2165 } else {
2166 if (!inv_file)
2167 inv_file = open_file;
2168 }
2169 }
2170 }
2171 /* couldn't find useable FH with same pid, try any available */
2172 if (!any_available) {
2173 any_available = true;
2174 goto refind_writable;
2175 }
2176
2177 if (inv_file) {
2178 any_available = false;
2179 cifsFileInfo_get(inv_file);
2180 }
2181
2182 spin_unlock(&cifs_inode->open_file_lock);
2183
2184 if (inv_file) {
2185 rc = cifs_reopen_file(inv_file, false);
2186 if (!rc) {
2187 *ret_file = inv_file;
2188 return 0;
2189 }
2190
2191 spin_lock(&cifs_inode->open_file_lock);
2192 list_move_tail(&inv_file->flist, &cifs_inode->openFileList);
2193 spin_unlock(&cifs_inode->open_file_lock);
2194 cifsFileInfo_put(inv_file);
2195 ++refind;
2196 inv_file = NULL;
2197 spin_lock(&cifs_inode->open_file_lock);
2198 goto refind_writable;
2199 }
2200
2201 return rc;
2202 }
2203
2204 struct cifsFileInfo *
find_writable_file(struct cifsInodeInfo * cifs_inode,int flags)2205 find_writable_file(struct cifsInodeInfo *cifs_inode, int flags)
2206 {
2207 struct cifsFileInfo *cfile;
2208 int rc;
2209
2210 rc = cifs_get_writable_file(cifs_inode, flags, &cfile);
2211 if (rc)
2212 cifs_dbg(FYI, "Couldn't find writable handle rc=%d\n", rc);
2213
2214 return cfile;
2215 }
2216
2217 int
cifs_get_writable_path(struct cifs_tcon * tcon,const char * name,int flags,struct cifsFileInfo ** ret_file)2218 cifs_get_writable_path(struct cifs_tcon *tcon, const char *name,
2219 int flags,
2220 struct cifsFileInfo **ret_file)
2221 {
2222 struct cifsFileInfo *cfile;
2223 void *page = alloc_dentry_path();
2224
2225 *ret_file = NULL;
2226
2227 spin_lock(&tcon->open_file_lock);
2228 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
2229 struct cifsInodeInfo *cinode;
2230 const char *full_path = build_path_from_dentry(cfile->dentry, page);
2231 if (IS_ERR(full_path)) {
2232 spin_unlock(&tcon->open_file_lock);
2233 free_dentry_path(page);
2234 return PTR_ERR(full_path);
2235 }
2236 if (strcmp(full_path, name))
2237 continue;
2238
2239 cinode = CIFS_I(d_inode(cfile->dentry));
2240 spin_unlock(&tcon->open_file_lock);
2241 free_dentry_path(page);
2242 return cifs_get_writable_file(cinode, flags, ret_file);
2243 }
2244
2245 spin_unlock(&tcon->open_file_lock);
2246 free_dentry_path(page);
2247 return -ENOENT;
2248 }
2249
2250 int
cifs_get_readable_path(struct cifs_tcon * tcon,const char * name,struct cifsFileInfo ** ret_file)2251 cifs_get_readable_path(struct cifs_tcon *tcon, const char *name,
2252 struct cifsFileInfo **ret_file)
2253 {
2254 struct cifsFileInfo *cfile;
2255 void *page = alloc_dentry_path();
2256
2257 *ret_file = NULL;
2258
2259 spin_lock(&tcon->open_file_lock);
2260 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
2261 struct cifsInodeInfo *cinode;
2262 const char *full_path = build_path_from_dentry(cfile->dentry, page);
2263 if (IS_ERR(full_path)) {
2264 spin_unlock(&tcon->open_file_lock);
2265 free_dentry_path(page);
2266 return PTR_ERR(full_path);
2267 }
2268 if (strcmp(full_path, name))
2269 continue;
2270
2271 cinode = CIFS_I(d_inode(cfile->dentry));
2272 spin_unlock(&tcon->open_file_lock);
2273 free_dentry_path(page);
2274 *ret_file = find_readable_file(cinode, 0);
2275 return *ret_file ? 0 : -ENOENT;
2276 }
2277
2278 spin_unlock(&tcon->open_file_lock);
2279 free_dentry_path(page);
2280 return -ENOENT;
2281 }
2282
2283 void
cifs_writedata_release(struct kref * refcount)2284 cifs_writedata_release(struct kref *refcount)
2285 {
2286 struct cifs_writedata *wdata = container_of(refcount,
2287 struct cifs_writedata, refcount);
2288 #ifdef CONFIG_CIFS_SMB_DIRECT
2289 if (wdata->mr) {
2290 smbd_deregister_mr(wdata->mr);
2291 wdata->mr = NULL;
2292 }
2293 #endif
2294
2295 if (wdata->cfile)
2296 cifsFileInfo_put(wdata->cfile);
2297
2298 kvfree(wdata->pages);
2299 kfree(wdata);
2300 }
2301
2302 /*
2303 * Write failed with a retryable error. Resend the write request. It's also
2304 * possible that the page was redirtied so re-clean the page.
2305 */
2306 static void
cifs_writev_requeue(struct cifs_writedata * wdata)2307 cifs_writev_requeue(struct cifs_writedata *wdata)
2308 {
2309 int i, rc = 0;
2310 struct inode *inode = d_inode(wdata->cfile->dentry);
2311 struct TCP_Server_Info *server;
2312 unsigned int rest_len;
2313
2314 server = tlink_tcon(wdata->cfile->tlink)->ses->server;
2315 i = 0;
2316 rest_len = wdata->bytes;
2317 do {
2318 struct cifs_writedata *wdata2;
2319 unsigned int j, nr_pages, wsize, tailsz, cur_len;
2320
2321 wsize = server->ops->wp_retry_size(inode);
2322 if (wsize < rest_len) {
2323 nr_pages = wsize / PAGE_SIZE;
2324 if (!nr_pages) {
2325 rc = -EOPNOTSUPP;
2326 break;
2327 }
2328 cur_len = nr_pages * PAGE_SIZE;
2329 tailsz = PAGE_SIZE;
2330 } else {
2331 nr_pages = DIV_ROUND_UP(rest_len, PAGE_SIZE);
2332 cur_len = rest_len;
2333 tailsz = rest_len - (nr_pages - 1) * PAGE_SIZE;
2334 }
2335
2336 wdata2 = cifs_writedata_alloc(nr_pages, cifs_writev_complete);
2337 if (!wdata2) {
2338 rc = -ENOMEM;
2339 break;
2340 }
2341
2342 for (j = 0; j < nr_pages; j++) {
2343 wdata2->pages[j] = wdata->pages[i + j];
2344 lock_page(wdata2->pages[j]);
2345 clear_page_dirty_for_io(wdata2->pages[j]);
2346 }
2347
2348 wdata2->sync_mode = wdata->sync_mode;
2349 wdata2->nr_pages = nr_pages;
2350 wdata2->offset = page_offset(wdata2->pages[0]);
2351 wdata2->pagesz = PAGE_SIZE;
2352 wdata2->tailsz = tailsz;
2353 wdata2->bytes = cur_len;
2354
2355 rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY,
2356 &wdata2->cfile);
2357 if (!wdata2->cfile) {
2358 cifs_dbg(VFS, "No writable handle to retry writepages rc=%d\n",
2359 rc);
2360 if (!is_retryable_error(rc))
2361 rc = -EBADF;
2362 } else {
2363 wdata2->pid = wdata2->cfile->pid;
2364 rc = server->ops->async_writev(wdata2,
2365 cifs_writedata_release);
2366 }
2367
2368 for (j = 0; j < nr_pages; j++) {
2369 unlock_page(wdata2->pages[j]);
2370 if (rc != 0 && !is_retryable_error(rc)) {
2371 SetPageError(wdata2->pages[j]);
2372 end_page_writeback(wdata2->pages[j]);
2373 put_page(wdata2->pages[j]);
2374 }
2375 }
2376
2377 kref_put(&wdata2->refcount, cifs_writedata_release);
2378 if (rc) {
2379 if (is_retryable_error(rc))
2380 continue;
2381 i += nr_pages;
2382 break;
2383 }
2384
2385 rest_len -= cur_len;
2386 i += nr_pages;
2387 } while (i < wdata->nr_pages);
2388
2389 /* cleanup remaining pages from the original wdata */
2390 for (; i < wdata->nr_pages; i++) {
2391 SetPageError(wdata->pages[i]);
2392 end_page_writeback(wdata->pages[i]);
2393 put_page(wdata->pages[i]);
2394 }
2395
2396 if (rc != 0 && !is_retryable_error(rc))
2397 mapping_set_error(inode->i_mapping, rc);
2398 kref_put(&wdata->refcount, cifs_writedata_release);
2399 }
2400
2401 void
cifs_writev_complete(struct work_struct * work)2402 cifs_writev_complete(struct work_struct *work)
2403 {
2404 struct cifs_writedata *wdata = container_of(work,
2405 struct cifs_writedata, work);
2406 struct inode *inode = d_inode(wdata->cfile->dentry);
2407 int i = 0;
2408
2409 if (wdata->result == 0) {
2410 spin_lock(&inode->i_lock);
2411 cifs_update_eof(CIFS_I(inode), wdata->offset, wdata->bytes);
2412 spin_unlock(&inode->i_lock);
2413 cifs_stats_bytes_written(tlink_tcon(wdata->cfile->tlink),
2414 wdata->bytes);
2415 } else if (wdata->sync_mode == WB_SYNC_ALL && wdata->result == -EAGAIN)
2416 return cifs_writev_requeue(wdata);
2417
2418 for (i = 0; i < wdata->nr_pages; i++) {
2419 struct page *page = wdata->pages[i];
2420
2421 if (wdata->result == -EAGAIN)
2422 __set_page_dirty_nobuffers(page);
2423 else if (wdata->result < 0)
2424 SetPageError(page);
2425 end_page_writeback(page);
2426 cifs_readpage_to_fscache(inode, page);
2427 put_page(page);
2428 }
2429 if (wdata->result != -EAGAIN)
2430 mapping_set_error(inode->i_mapping, wdata->result);
2431 kref_put(&wdata->refcount, cifs_writedata_release);
2432 }
2433
2434 struct cifs_writedata *
cifs_writedata_alloc(unsigned int nr_pages,work_func_t complete)2435 cifs_writedata_alloc(unsigned int nr_pages, work_func_t complete)
2436 {
2437 struct cifs_writedata *writedata = NULL;
2438 struct page **pages =
2439 kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
2440 if (pages) {
2441 writedata = cifs_writedata_direct_alloc(pages, complete);
2442 if (!writedata)
2443 kvfree(pages);
2444 }
2445
2446 return writedata;
2447 }
2448
2449 struct cifs_writedata *
cifs_writedata_direct_alloc(struct page ** pages,work_func_t complete)2450 cifs_writedata_direct_alloc(struct page **pages, work_func_t complete)
2451 {
2452 struct cifs_writedata *wdata;
2453
2454 wdata = kzalloc(sizeof(*wdata), GFP_NOFS);
2455 if (wdata != NULL) {
2456 wdata->pages = pages;
2457 kref_init(&wdata->refcount);
2458 INIT_LIST_HEAD(&wdata->list);
2459 init_completion(&wdata->done);
2460 INIT_WORK(&wdata->work, complete);
2461 }
2462 return wdata;
2463 }
2464
2465
cifs_partialpagewrite(struct page * page,unsigned from,unsigned to)2466 static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
2467 {
2468 struct address_space *mapping = page->mapping;
2469 loff_t offset = (loff_t)page->index << PAGE_SHIFT;
2470 char *write_data;
2471 int rc = -EFAULT;
2472 int bytes_written = 0;
2473 struct inode *inode;
2474 struct cifsFileInfo *open_file;
2475
2476 if (!mapping || !mapping->host)
2477 return -EFAULT;
2478
2479 inode = page->mapping->host;
2480
2481 offset += (loff_t)from;
2482 write_data = kmap(page);
2483 write_data += from;
2484
2485 if ((to > PAGE_SIZE) || (from > to)) {
2486 kunmap(page);
2487 return -EIO;
2488 }
2489
2490 /* racing with truncate? */
2491 if (offset > mapping->host->i_size) {
2492 kunmap(page);
2493 return 0; /* don't care */
2494 }
2495
2496 /* check to make sure that we are not extending the file */
2497 if (mapping->host->i_size - offset < (loff_t)to)
2498 to = (unsigned)(mapping->host->i_size - offset);
2499
2500 rc = cifs_get_writable_file(CIFS_I(mapping->host), FIND_WR_ANY,
2501 &open_file);
2502 if (!rc) {
2503 bytes_written = cifs_write(open_file, open_file->pid,
2504 write_data, to - from, &offset);
2505 cifsFileInfo_put(open_file);
2506 /* Does mm or vfs already set times? */
2507 inode->i_atime = inode->i_mtime = current_time(inode);
2508 if ((bytes_written > 0) && (offset))
2509 rc = 0;
2510 else if (bytes_written < 0)
2511 rc = bytes_written;
2512 else
2513 rc = -EFAULT;
2514 } else {
2515 cifs_dbg(FYI, "No writable handle for write page rc=%d\n", rc);
2516 if (!is_retryable_error(rc))
2517 rc = -EIO;
2518 }
2519
2520 kunmap(page);
2521 return rc;
2522 }
2523
2524 static struct cifs_writedata *
wdata_alloc_and_fillpages(pgoff_t tofind,struct address_space * mapping,pgoff_t end,pgoff_t * index,unsigned int * found_pages)2525 wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
2526 pgoff_t end, pgoff_t *index,
2527 unsigned int *found_pages)
2528 {
2529 struct cifs_writedata *wdata;
2530
2531 wdata = cifs_writedata_alloc((unsigned int)tofind,
2532 cifs_writev_complete);
2533 if (!wdata)
2534 return NULL;
2535
2536 *found_pages = find_get_pages_range_tag(mapping, index, end,
2537 PAGECACHE_TAG_DIRTY, tofind, wdata->pages);
2538 return wdata;
2539 }
2540
2541 static unsigned int
wdata_prepare_pages(struct cifs_writedata * wdata,unsigned int found_pages,struct address_space * mapping,struct writeback_control * wbc,pgoff_t end,pgoff_t * index,pgoff_t * next,bool * done)2542 wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
2543 struct address_space *mapping,
2544 struct writeback_control *wbc,
2545 pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
2546 {
2547 unsigned int nr_pages = 0, i;
2548 struct page *page;
2549
2550 for (i = 0; i < found_pages; i++) {
2551 page = wdata->pages[i];
2552 /*
2553 * At this point we hold neither the i_pages lock nor the
2554 * page lock: the page may be truncated or invalidated
2555 * (changing page->mapping to NULL), or even swizzled
2556 * back from swapper_space to tmpfs file mapping
2557 */
2558
2559 if (nr_pages == 0)
2560 lock_page(page);
2561 else if (!trylock_page(page))
2562 break;
2563
2564 if (unlikely(page->mapping != mapping)) {
2565 unlock_page(page);
2566 break;
2567 }
2568
2569 if (!wbc->range_cyclic && page->index > end) {
2570 *done = true;
2571 unlock_page(page);
2572 break;
2573 }
2574
2575 if (*next && (page->index != *next)) {
2576 /* Not next consecutive page */
2577 unlock_page(page);
2578 break;
2579 }
2580
2581 if (wbc->sync_mode != WB_SYNC_NONE)
2582 wait_on_page_writeback(page);
2583
2584 if (PageWriteback(page) ||
2585 !clear_page_dirty_for_io(page)) {
2586 unlock_page(page);
2587 break;
2588 }
2589
2590 /*
2591 * This actually clears the dirty bit in the radix tree.
2592 * See cifs_writepage() for more commentary.
2593 */
2594 set_page_writeback(page);
2595 if (page_offset(page) >= i_size_read(mapping->host)) {
2596 *done = true;
2597 unlock_page(page);
2598 end_page_writeback(page);
2599 break;
2600 }
2601
2602 wdata->pages[i] = page;
2603 *next = page->index + 1;
2604 ++nr_pages;
2605 }
2606
2607 /* reset index to refind any pages skipped */
2608 if (nr_pages == 0)
2609 *index = wdata->pages[0]->index + 1;
2610
2611 /* put any pages we aren't going to use */
2612 for (i = nr_pages; i < found_pages; i++) {
2613 put_page(wdata->pages[i]);
2614 wdata->pages[i] = NULL;
2615 }
2616
2617 return nr_pages;
2618 }
2619
2620 static int
wdata_send_pages(struct cifs_writedata * wdata,unsigned int nr_pages,struct address_space * mapping,struct writeback_control * wbc)2621 wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
2622 struct address_space *mapping, struct writeback_control *wbc)
2623 {
2624 int rc;
2625
2626 wdata->sync_mode = wbc->sync_mode;
2627 wdata->nr_pages = nr_pages;
2628 wdata->offset = page_offset(wdata->pages[0]);
2629 wdata->pagesz = PAGE_SIZE;
2630 wdata->tailsz = min(i_size_read(mapping->host) -
2631 page_offset(wdata->pages[nr_pages - 1]),
2632 (loff_t)PAGE_SIZE);
2633 wdata->bytes = ((nr_pages - 1) * PAGE_SIZE) + wdata->tailsz;
2634 wdata->pid = wdata->cfile->pid;
2635
2636 rc = adjust_credits(wdata->server, &wdata->credits, wdata->bytes);
2637 if (rc)
2638 return rc;
2639
2640 if (wdata->cfile->invalidHandle)
2641 rc = -EAGAIN;
2642 else
2643 rc = wdata->server->ops->async_writev(wdata,
2644 cifs_writedata_release);
2645
2646 return rc;
2647 }
2648
cifs_writepages(struct address_space * mapping,struct writeback_control * wbc)2649 static int cifs_writepages(struct address_space *mapping,
2650 struct writeback_control *wbc)
2651 {
2652 struct inode *inode = mapping->host;
2653 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2654 struct TCP_Server_Info *server;
2655 bool done = false, scanned = false, range_whole = false;
2656 pgoff_t end, index;
2657 struct cifs_writedata *wdata;
2658 struct cifsFileInfo *cfile = NULL;
2659 int rc = 0;
2660 int saved_rc = 0;
2661 unsigned int xid;
2662
2663 /*
2664 * If wsize is smaller than the page cache size, default to writing
2665 * one page at a time via cifs_writepage
2666 */
2667 if (cifs_sb->ctx->wsize < PAGE_SIZE)
2668 return generic_writepages(mapping, wbc);
2669
2670 xid = get_xid();
2671 if (wbc->range_cyclic) {
2672 index = mapping->writeback_index; /* Start from prev offset */
2673 end = -1;
2674 } else {
2675 index = wbc->range_start >> PAGE_SHIFT;
2676 end = wbc->range_end >> PAGE_SHIFT;
2677 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
2678 range_whole = true;
2679 scanned = true;
2680 }
2681 server = cifs_pick_channel(cifs_sb_master_tcon(cifs_sb)->ses);
2682
2683 retry:
2684 while (!done && index <= end) {
2685 unsigned int i, nr_pages, found_pages, wsize;
2686 pgoff_t next = 0, tofind, saved_index = index;
2687 struct cifs_credits credits_on_stack;
2688 struct cifs_credits *credits = &credits_on_stack;
2689 int get_file_rc = 0;
2690
2691 if (cfile)
2692 cifsFileInfo_put(cfile);
2693
2694 rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY, &cfile);
2695
2696 /* in case of an error store it to return later */
2697 if (rc)
2698 get_file_rc = rc;
2699
2700 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
2701 &wsize, credits);
2702 if (rc != 0) {
2703 done = true;
2704 break;
2705 }
2706
2707 tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1;
2708
2709 wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
2710 &found_pages);
2711 if (!wdata) {
2712 rc = -ENOMEM;
2713 done = true;
2714 add_credits_and_wake_if(server, credits, 0);
2715 break;
2716 }
2717
2718 if (found_pages == 0) {
2719 kref_put(&wdata->refcount, cifs_writedata_release);
2720 add_credits_and_wake_if(server, credits, 0);
2721 break;
2722 }
2723
2724 nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
2725 end, &index, &next, &done);
2726
2727 /* nothing to write? */
2728 if (nr_pages == 0) {
2729 kref_put(&wdata->refcount, cifs_writedata_release);
2730 add_credits_and_wake_if(server, credits, 0);
2731 continue;
2732 }
2733
2734 wdata->credits = credits_on_stack;
2735 wdata->cfile = cfile;
2736 wdata->server = server;
2737 cfile = NULL;
2738
2739 if (!wdata->cfile) {
2740 cifs_dbg(VFS, "No writable handle in writepages rc=%d\n",
2741 get_file_rc);
2742 if (is_retryable_error(get_file_rc))
2743 rc = get_file_rc;
2744 else
2745 rc = -EBADF;
2746 } else
2747 rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
2748
2749 for (i = 0; i < nr_pages; ++i)
2750 unlock_page(wdata->pages[i]);
2751
2752 /* send failure -- clean up the mess */
2753 if (rc != 0) {
2754 add_credits_and_wake_if(server, &wdata->credits, 0);
2755 for (i = 0; i < nr_pages; ++i) {
2756 if (is_retryable_error(rc))
2757 redirty_page_for_writepage(wbc,
2758 wdata->pages[i]);
2759 else
2760 SetPageError(wdata->pages[i]);
2761 end_page_writeback(wdata->pages[i]);
2762 put_page(wdata->pages[i]);
2763 }
2764 if (!is_retryable_error(rc))
2765 mapping_set_error(mapping, rc);
2766 }
2767 kref_put(&wdata->refcount, cifs_writedata_release);
2768
2769 if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) {
2770 index = saved_index;
2771 continue;
2772 }
2773
2774 /* Return immediately if we received a signal during writing */
2775 if (is_interrupt_error(rc)) {
2776 done = true;
2777 break;
2778 }
2779
2780 if (rc != 0 && saved_rc == 0)
2781 saved_rc = rc;
2782
2783 wbc->nr_to_write -= nr_pages;
2784 if (wbc->nr_to_write <= 0)
2785 done = true;
2786
2787 index = next;
2788 }
2789
2790 if (!scanned && !done) {
2791 /*
2792 * We hit the last page and there is more work to be done: wrap
2793 * back to the start of the file
2794 */
2795 scanned = true;
2796 index = 0;
2797 goto retry;
2798 }
2799
2800 if (saved_rc != 0)
2801 rc = saved_rc;
2802
2803 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
2804 mapping->writeback_index = index;
2805
2806 if (cfile)
2807 cifsFileInfo_put(cfile);
2808 free_xid(xid);
2809 /* Indication to update ctime and mtime as close is deferred */
2810 set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
2811 return rc;
2812 }
2813
2814 static int
cifs_writepage_locked(struct page * page,struct writeback_control * wbc)2815 cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
2816 {
2817 int rc;
2818 unsigned int xid;
2819
2820 xid = get_xid();
2821 /* BB add check for wbc flags */
2822 get_page(page);
2823 if (!PageUptodate(page))
2824 cifs_dbg(FYI, "ppw - page not up to date\n");
2825
2826 /*
2827 * Set the "writeback" flag, and clear "dirty" in the radix tree.
2828 *
2829 * A writepage() implementation always needs to do either this,
2830 * or re-dirty the page with "redirty_page_for_writepage()" in
2831 * the case of a failure.
2832 *
2833 * Just unlocking the page will cause the radix tree tag-bits
2834 * to fail to update with the state of the page correctly.
2835 */
2836 set_page_writeback(page);
2837 retry_write:
2838 rc = cifs_partialpagewrite(page, 0, PAGE_SIZE);
2839 if (is_retryable_error(rc)) {
2840 if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN)
2841 goto retry_write;
2842 redirty_page_for_writepage(wbc, page);
2843 } else if (rc != 0) {
2844 SetPageError(page);
2845 mapping_set_error(page->mapping, rc);
2846 } else {
2847 SetPageUptodate(page);
2848 }
2849 end_page_writeback(page);
2850 put_page(page);
2851 free_xid(xid);
2852 return rc;
2853 }
2854
cifs_writepage(struct page * page,struct writeback_control * wbc)2855 static int cifs_writepage(struct page *page, struct writeback_control *wbc)
2856 {
2857 int rc = cifs_writepage_locked(page, wbc);
2858 unlock_page(page);
2859 return rc;
2860 }
2861
cifs_write_end(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct page * page,void * fsdata)2862 static int cifs_write_end(struct file *file, struct address_space *mapping,
2863 loff_t pos, unsigned len, unsigned copied,
2864 struct page *page, void *fsdata)
2865 {
2866 int rc;
2867 struct inode *inode = mapping->host;
2868 struct cifsFileInfo *cfile = file->private_data;
2869 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
2870 __u32 pid;
2871
2872 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2873 pid = cfile->pid;
2874 else
2875 pid = current->tgid;
2876
2877 cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
2878 page, pos, copied);
2879
2880 if (PageChecked(page)) {
2881 if (copied == len)
2882 SetPageUptodate(page);
2883 ClearPageChecked(page);
2884 } else if (!PageUptodate(page) && copied == PAGE_SIZE)
2885 SetPageUptodate(page);
2886
2887 if (!PageUptodate(page)) {
2888 char *page_data;
2889 unsigned offset = pos & (PAGE_SIZE - 1);
2890 unsigned int xid;
2891
2892 xid = get_xid();
2893 /* this is probably better than directly calling
2894 partialpage_write since in this function the file handle is
2895 known which we might as well leverage */
2896 /* BB check if anything else missing out of ppw
2897 such as updating last write time */
2898 page_data = kmap(page);
2899 rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
2900 /* if (rc < 0) should we set writebehind rc? */
2901 kunmap(page);
2902
2903 free_xid(xid);
2904 } else {
2905 rc = copied;
2906 pos += copied;
2907 set_page_dirty(page);
2908 }
2909
2910 if (rc > 0) {
2911 spin_lock(&inode->i_lock);
2912 if (pos > inode->i_size) {
2913 i_size_write(inode, pos);
2914 inode->i_blocks = (512 - 1 + pos) >> 9;
2915 }
2916 spin_unlock(&inode->i_lock);
2917 }
2918
2919 unlock_page(page);
2920 put_page(page);
2921 /* Indication to update ctime and mtime as close is deferred */
2922 set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
2923
2924 return rc;
2925 }
2926
cifs_strict_fsync(struct file * file,loff_t start,loff_t end,int datasync)2927 int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
2928 int datasync)
2929 {
2930 unsigned int xid;
2931 int rc = 0;
2932 struct cifs_tcon *tcon;
2933 struct TCP_Server_Info *server;
2934 struct cifsFileInfo *smbfile = file->private_data;
2935 struct inode *inode = file_inode(file);
2936 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2937
2938 rc = file_write_and_wait_range(file, start, end);
2939 if (rc) {
2940 trace_cifs_fsync_err(inode->i_ino, rc);
2941 return rc;
2942 }
2943
2944 xid = get_xid();
2945
2946 cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
2947 file, datasync);
2948
2949 if (!CIFS_CACHE_READ(CIFS_I(inode))) {
2950 rc = cifs_zap_mapping(inode);
2951 if (rc) {
2952 cifs_dbg(FYI, "rc: %d during invalidate phase\n", rc);
2953 rc = 0; /* don't care about it in fsync */
2954 }
2955 }
2956
2957 tcon = tlink_tcon(smbfile->tlink);
2958 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
2959 server = tcon->ses->server;
2960 if (server->ops->flush == NULL) {
2961 rc = -ENOSYS;
2962 goto strict_fsync_exit;
2963 }
2964
2965 if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
2966 smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
2967 if (smbfile) {
2968 rc = server->ops->flush(xid, tcon, &smbfile->fid);
2969 cifsFileInfo_put(smbfile);
2970 } else
2971 cifs_dbg(FYI, "ignore fsync for file not open for write\n");
2972 } else
2973 rc = server->ops->flush(xid, tcon, &smbfile->fid);
2974 }
2975
2976 strict_fsync_exit:
2977 free_xid(xid);
2978 return rc;
2979 }
2980
cifs_fsync(struct file * file,loff_t start,loff_t end,int datasync)2981 int cifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2982 {
2983 unsigned int xid;
2984 int rc = 0;
2985 struct cifs_tcon *tcon;
2986 struct TCP_Server_Info *server;
2987 struct cifsFileInfo *smbfile = file->private_data;
2988 struct inode *inode = file_inode(file);
2989 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
2990
2991 rc = file_write_and_wait_range(file, start, end);
2992 if (rc) {
2993 trace_cifs_fsync_err(file_inode(file)->i_ino, rc);
2994 return rc;
2995 }
2996
2997 xid = get_xid();
2998
2999 cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
3000 file, datasync);
3001
3002 tcon = tlink_tcon(smbfile->tlink);
3003 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
3004 server = tcon->ses->server;
3005 if (server->ops->flush == NULL) {
3006 rc = -ENOSYS;
3007 goto fsync_exit;
3008 }
3009
3010 if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
3011 smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
3012 if (smbfile) {
3013 rc = server->ops->flush(xid, tcon, &smbfile->fid);
3014 cifsFileInfo_put(smbfile);
3015 } else
3016 cifs_dbg(FYI, "ignore fsync for file not open for write\n");
3017 } else
3018 rc = server->ops->flush(xid, tcon, &smbfile->fid);
3019 }
3020
3021 fsync_exit:
3022 free_xid(xid);
3023 return rc;
3024 }
3025
3026 /*
3027 * As file closes, flush all cached write data for this inode checking
3028 * for write behind errors.
3029 */
cifs_flush(struct file * file,fl_owner_t id)3030 int cifs_flush(struct file *file, fl_owner_t id)
3031 {
3032 struct inode *inode = file_inode(file);
3033 int rc = 0;
3034
3035 if (file->f_mode & FMODE_WRITE)
3036 rc = filemap_write_and_wait(inode->i_mapping);
3037
3038 cifs_dbg(FYI, "Flush inode %p file %p rc %d\n", inode, file, rc);
3039 if (rc) {
3040 /* get more nuanced writeback errors */
3041 rc = filemap_check_wb_err(file->f_mapping, 0);
3042 trace_cifs_flush_err(inode->i_ino, rc);
3043 }
3044 return rc;
3045 }
3046
3047 static int
cifs_write_allocate_pages(struct page ** pages,unsigned long num_pages)3048 cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
3049 {
3050 int rc = 0;
3051 unsigned long i;
3052
3053 for (i = 0; i < num_pages; i++) {
3054 pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
3055 if (!pages[i]) {
3056 /*
3057 * save number of pages we have already allocated and
3058 * return with ENOMEM error
3059 */
3060 num_pages = i;
3061 rc = -ENOMEM;
3062 break;
3063 }
3064 }
3065
3066 if (rc) {
3067 for (i = 0; i < num_pages; i++)
3068 put_page(pages[i]);
3069 }
3070 return rc;
3071 }
3072
3073 static inline
get_numpages(const size_t wsize,const size_t len,size_t * cur_len)3074 size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
3075 {
3076 size_t num_pages;
3077 size_t clen;
3078
3079 clen = min_t(const size_t, len, wsize);
3080 num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
3081
3082 if (cur_len)
3083 *cur_len = clen;
3084
3085 return num_pages;
3086 }
3087
3088 static void
cifs_uncached_writedata_release(struct kref * refcount)3089 cifs_uncached_writedata_release(struct kref *refcount)
3090 {
3091 int i;
3092 struct cifs_writedata *wdata = container_of(refcount,
3093 struct cifs_writedata, refcount);
3094
3095 kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
3096 for (i = 0; i < wdata->nr_pages; i++)
3097 put_page(wdata->pages[i]);
3098 cifs_writedata_release(refcount);
3099 }
3100
3101 static void collect_uncached_write_data(struct cifs_aio_ctx *ctx);
3102
3103 static void
cifs_uncached_writev_complete(struct work_struct * work)3104 cifs_uncached_writev_complete(struct work_struct *work)
3105 {
3106 struct cifs_writedata *wdata = container_of(work,
3107 struct cifs_writedata, work);
3108 struct inode *inode = d_inode(wdata->cfile->dentry);
3109 struct cifsInodeInfo *cifsi = CIFS_I(inode);
3110
3111 spin_lock(&inode->i_lock);
3112 cifs_update_eof(cifsi, wdata->offset, wdata->bytes);
3113 if (cifsi->server_eof > inode->i_size)
3114 i_size_write(inode, cifsi->server_eof);
3115 spin_unlock(&inode->i_lock);
3116
3117 complete(&wdata->done);
3118 collect_uncached_write_data(wdata->ctx);
3119 /* the below call can possibly free the last ref to aio ctx */
3120 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
3121 }
3122
3123 static int
wdata_fill_from_iovec(struct cifs_writedata * wdata,struct iov_iter * from,size_t * len,unsigned long * num_pages)3124 wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
3125 size_t *len, unsigned long *num_pages)
3126 {
3127 size_t save_len, copied, bytes, cur_len = *len;
3128 unsigned long i, nr_pages = *num_pages;
3129
3130 save_len = cur_len;
3131 for (i = 0; i < nr_pages; i++) {
3132 bytes = min_t(const size_t, cur_len, PAGE_SIZE);
3133 copied = copy_page_from_iter(wdata->pages[i], 0, bytes, from);
3134 cur_len -= copied;
3135 /*
3136 * If we didn't copy as much as we expected, then that
3137 * may mean we trod into an unmapped area. Stop copying
3138 * at that point. On the next pass through the big
3139 * loop, we'll likely end up getting a zero-length
3140 * write and bailing out of it.
3141 */
3142 if (copied < bytes)
3143 break;
3144 }
3145 cur_len = save_len - cur_len;
3146 *len = cur_len;
3147
3148 /*
3149 * If we have no data to send, then that probably means that
3150 * the copy above failed altogether. That's most likely because
3151 * the address in the iovec was bogus. Return -EFAULT and let
3152 * the caller free anything we allocated and bail out.
3153 */
3154 if (!cur_len)
3155 return -EFAULT;
3156
3157 /*
3158 * i + 1 now represents the number of pages we actually used in
3159 * the copy phase above.
3160 */
3161 *num_pages = i + 1;
3162 return 0;
3163 }
3164
3165 static int
cifs_resend_wdata(struct cifs_writedata * wdata,struct list_head * wdata_list,struct cifs_aio_ctx * ctx)3166 cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
3167 struct cifs_aio_ctx *ctx)
3168 {
3169 unsigned int wsize;
3170 struct cifs_credits credits;
3171 int rc;
3172 struct TCP_Server_Info *server = wdata->server;
3173
3174 do {
3175 if (wdata->cfile->invalidHandle) {
3176 rc = cifs_reopen_file(wdata->cfile, false);
3177 if (rc == -EAGAIN)
3178 continue;
3179 else if (rc)
3180 break;
3181 }
3182
3183
3184 /*
3185 * Wait for credits to resend this wdata.
3186 * Note: we are attempting to resend the whole wdata not in
3187 * segments
3188 */
3189 do {
3190 rc = server->ops->wait_mtu_credits(server, wdata->bytes,
3191 &wsize, &credits);
3192 if (rc)
3193 goto fail;
3194
3195 if (wsize < wdata->bytes) {
3196 add_credits_and_wake_if(server, &credits, 0);
3197 msleep(1000);
3198 }
3199 } while (wsize < wdata->bytes);
3200 wdata->credits = credits;
3201
3202 rc = adjust_credits(server, &wdata->credits, wdata->bytes);
3203
3204 if (!rc) {
3205 if (wdata->cfile->invalidHandle)
3206 rc = -EAGAIN;
3207 else {
3208 #ifdef CONFIG_CIFS_SMB_DIRECT
3209 if (wdata->mr) {
3210 wdata->mr->need_invalidate = true;
3211 smbd_deregister_mr(wdata->mr);
3212 wdata->mr = NULL;
3213 }
3214 #endif
3215 rc = server->ops->async_writev(wdata,
3216 cifs_uncached_writedata_release);
3217 }
3218 }
3219
3220 /* If the write was successfully sent, we are done */
3221 if (!rc) {
3222 list_add_tail(&wdata->list, wdata_list);
3223 return 0;
3224 }
3225
3226 /* Roll back credits and retry if needed */
3227 add_credits_and_wake_if(server, &wdata->credits, 0);
3228 } while (rc == -EAGAIN);
3229
3230 fail:
3231 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
3232 return rc;
3233 }
3234
3235 static int
cifs_write_from_iter(loff_t offset,size_t len,struct iov_iter * from,struct cifsFileInfo * open_file,struct cifs_sb_info * cifs_sb,struct list_head * wdata_list,struct cifs_aio_ctx * ctx)3236 cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
3237 struct cifsFileInfo *open_file,
3238 struct cifs_sb_info *cifs_sb, struct list_head *wdata_list,
3239 struct cifs_aio_ctx *ctx)
3240 {
3241 int rc = 0;
3242 size_t cur_len;
3243 unsigned long nr_pages, num_pages, i;
3244 struct cifs_writedata *wdata;
3245 struct iov_iter saved_from = *from;
3246 loff_t saved_offset = offset;
3247 pid_t pid;
3248 struct TCP_Server_Info *server;
3249 struct page **pagevec;
3250 size_t start;
3251 unsigned int xid;
3252
3253 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3254 pid = open_file->pid;
3255 else
3256 pid = current->tgid;
3257
3258 server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
3259 xid = get_xid();
3260
3261 do {
3262 unsigned int wsize;
3263 struct cifs_credits credits_on_stack;
3264 struct cifs_credits *credits = &credits_on_stack;
3265
3266 if (open_file->invalidHandle) {
3267 rc = cifs_reopen_file(open_file, false);
3268 if (rc == -EAGAIN)
3269 continue;
3270 else if (rc)
3271 break;
3272 }
3273
3274 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
3275 &wsize, credits);
3276 if (rc)
3277 break;
3278
3279 cur_len = min_t(const size_t, len, wsize);
3280
3281 if (ctx->direct_io) {
3282 ssize_t result;
3283
3284 result = iov_iter_get_pages_alloc2(
3285 from, &pagevec, cur_len, &start);
3286 if (result < 0) {
3287 cifs_dbg(VFS,
3288 "direct_writev couldn't get user pages (rc=%zd) iter type %d iov_offset %zd count %zd\n",
3289 result, iov_iter_type(from),
3290 from->iov_offset, from->count);
3291 dump_stack();
3292
3293 rc = result;
3294 add_credits_and_wake_if(server, credits, 0);
3295 break;
3296 }
3297 cur_len = (size_t)result;
3298
3299 nr_pages =
3300 (cur_len + start + PAGE_SIZE - 1) / PAGE_SIZE;
3301
3302 wdata = cifs_writedata_direct_alloc(pagevec,
3303 cifs_uncached_writev_complete);
3304 if (!wdata) {
3305 rc = -ENOMEM;
3306 for (i = 0; i < nr_pages; i++)
3307 put_page(pagevec[i]);
3308 kvfree(pagevec);
3309 add_credits_and_wake_if(server, credits, 0);
3310 break;
3311 }
3312
3313
3314 wdata->page_offset = start;
3315 wdata->tailsz =
3316 nr_pages > 1 ?
3317 cur_len - (PAGE_SIZE - start) -
3318 (nr_pages - 2) * PAGE_SIZE :
3319 cur_len;
3320 } else {
3321 nr_pages = get_numpages(wsize, len, &cur_len);
3322 wdata = cifs_writedata_alloc(nr_pages,
3323 cifs_uncached_writev_complete);
3324 if (!wdata) {
3325 rc = -ENOMEM;
3326 add_credits_and_wake_if(server, credits, 0);
3327 break;
3328 }
3329
3330 rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
3331 if (rc) {
3332 kvfree(wdata->pages);
3333 kfree(wdata);
3334 add_credits_and_wake_if(server, credits, 0);
3335 break;
3336 }
3337
3338 num_pages = nr_pages;
3339 rc = wdata_fill_from_iovec(
3340 wdata, from, &cur_len, &num_pages);
3341 if (rc) {
3342 for (i = 0; i < nr_pages; i++)
3343 put_page(wdata->pages[i]);
3344 kvfree(wdata->pages);
3345 kfree(wdata);
3346 add_credits_and_wake_if(server, credits, 0);
3347 break;
3348 }
3349
3350 /*
3351 * Bring nr_pages down to the number of pages we
3352 * actually used, and free any pages that we didn't use.
3353 */
3354 for ( ; nr_pages > num_pages; nr_pages--)
3355 put_page(wdata->pages[nr_pages - 1]);
3356
3357 wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
3358 }
3359
3360 wdata->sync_mode = WB_SYNC_ALL;
3361 wdata->nr_pages = nr_pages;
3362 wdata->offset = (__u64)offset;
3363 wdata->cfile = cifsFileInfo_get(open_file);
3364 wdata->server = server;
3365 wdata->pid = pid;
3366 wdata->bytes = cur_len;
3367 wdata->pagesz = PAGE_SIZE;
3368 wdata->credits = credits_on_stack;
3369 wdata->ctx = ctx;
3370 kref_get(&ctx->refcount);
3371
3372 rc = adjust_credits(server, &wdata->credits, wdata->bytes);
3373
3374 if (!rc) {
3375 if (wdata->cfile->invalidHandle)
3376 rc = -EAGAIN;
3377 else
3378 rc = server->ops->async_writev(wdata,
3379 cifs_uncached_writedata_release);
3380 }
3381
3382 if (rc) {
3383 add_credits_and_wake_if(server, &wdata->credits, 0);
3384 kref_put(&wdata->refcount,
3385 cifs_uncached_writedata_release);
3386 if (rc == -EAGAIN) {
3387 *from = saved_from;
3388 iov_iter_advance(from, offset - saved_offset);
3389 continue;
3390 }
3391 break;
3392 }
3393
3394 list_add_tail(&wdata->list, wdata_list);
3395 offset += cur_len;
3396 len -= cur_len;
3397 } while (len > 0);
3398
3399 free_xid(xid);
3400 return rc;
3401 }
3402
collect_uncached_write_data(struct cifs_aio_ctx * ctx)3403 static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
3404 {
3405 struct cifs_writedata *wdata, *tmp;
3406 struct cifs_tcon *tcon;
3407 struct cifs_sb_info *cifs_sb;
3408 struct dentry *dentry = ctx->cfile->dentry;
3409 ssize_t rc;
3410
3411 tcon = tlink_tcon(ctx->cfile->tlink);
3412 cifs_sb = CIFS_SB(dentry->d_sb);
3413
3414 mutex_lock(&ctx->aio_mutex);
3415
3416 if (list_empty(&ctx->list)) {
3417 mutex_unlock(&ctx->aio_mutex);
3418 return;
3419 }
3420
3421 rc = ctx->rc;
3422 /*
3423 * Wait for and collect replies for any successful sends in order of
3424 * increasing offset. Once an error is hit, then return without waiting
3425 * for any more replies.
3426 */
3427 restart_loop:
3428 list_for_each_entry_safe(wdata, tmp, &ctx->list, list) {
3429 if (!rc) {
3430 if (!try_wait_for_completion(&wdata->done)) {
3431 mutex_unlock(&ctx->aio_mutex);
3432 return;
3433 }
3434
3435 if (wdata->result)
3436 rc = wdata->result;
3437 else
3438 ctx->total_len += wdata->bytes;
3439
3440 /* resend call if it's a retryable error */
3441 if (rc == -EAGAIN) {
3442 struct list_head tmp_list;
3443 struct iov_iter tmp_from = ctx->iter;
3444
3445 INIT_LIST_HEAD(&tmp_list);
3446 list_del_init(&wdata->list);
3447
3448 if (ctx->direct_io)
3449 rc = cifs_resend_wdata(
3450 wdata, &tmp_list, ctx);
3451 else {
3452 iov_iter_advance(&tmp_from,
3453 wdata->offset - ctx->pos);
3454
3455 rc = cifs_write_from_iter(wdata->offset,
3456 wdata->bytes, &tmp_from,
3457 ctx->cfile, cifs_sb, &tmp_list,
3458 ctx);
3459
3460 kref_put(&wdata->refcount,
3461 cifs_uncached_writedata_release);
3462 }
3463
3464 list_splice(&tmp_list, &ctx->list);
3465 goto restart_loop;
3466 }
3467 }
3468 list_del_init(&wdata->list);
3469 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
3470 }
3471
3472 cifs_stats_bytes_written(tcon, ctx->total_len);
3473 set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(dentry->d_inode)->flags);
3474
3475 ctx->rc = (rc == 0) ? ctx->total_len : rc;
3476
3477 mutex_unlock(&ctx->aio_mutex);
3478
3479 if (ctx->iocb && ctx->iocb->ki_complete)
3480 ctx->iocb->ki_complete(ctx->iocb, ctx->rc);
3481 else
3482 complete(&ctx->done);
3483 }
3484
__cifs_writev(struct kiocb * iocb,struct iov_iter * from,bool direct)3485 static ssize_t __cifs_writev(
3486 struct kiocb *iocb, struct iov_iter *from, bool direct)
3487 {
3488 struct file *file = iocb->ki_filp;
3489 ssize_t total_written = 0;
3490 struct cifsFileInfo *cfile;
3491 struct cifs_tcon *tcon;
3492 struct cifs_sb_info *cifs_sb;
3493 struct cifs_aio_ctx *ctx;
3494 struct iov_iter saved_from = *from;
3495 size_t len = iov_iter_count(from);
3496 int rc;
3497
3498 /*
3499 * iov_iter_get_pages_alloc doesn't work with ITER_KVEC.
3500 * In this case, fall back to non-direct write function.
3501 * this could be improved by getting pages directly in ITER_KVEC
3502 */
3503 if (direct && iov_iter_is_kvec(from)) {
3504 cifs_dbg(FYI, "use non-direct cifs_writev for kvec I/O\n");
3505 direct = false;
3506 }
3507
3508 rc = generic_write_checks(iocb, from);
3509 if (rc <= 0)
3510 return rc;
3511
3512 cifs_sb = CIFS_FILE_SB(file);
3513 cfile = file->private_data;
3514 tcon = tlink_tcon(cfile->tlink);
3515
3516 if (!tcon->ses->server->ops->async_writev)
3517 return -ENOSYS;
3518
3519 ctx = cifs_aio_ctx_alloc();
3520 if (!ctx)
3521 return -ENOMEM;
3522
3523 ctx->cfile = cifsFileInfo_get(cfile);
3524
3525 if (!is_sync_kiocb(iocb))
3526 ctx->iocb = iocb;
3527
3528 ctx->pos = iocb->ki_pos;
3529
3530 if (direct) {
3531 ctx->direct_io = true;
3532 ctx->iter = *from;
3533 ctx->len = len;
3534 } else {
3535 rc = setup_aio_ctx_iter(ctx, from, WRITE);
3536 if (rc) {
3537 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3538 return rc;
3539 }
3540 }
3541
3542 /* grab a lock here due to read response handlers can access ctx */
3543 mutex_lock(&ctx->aio_mutex);
3544
3545 rc = cifs_write_from_iter(iocb->ki_pos, ctx->len, &saved_from,
3546 cfile, cifs_sb, &ctx->list, ctx);
3547
3548 /*
3549 * If at least one write was successfully sent, then discard any rc
3550 * value from the later writes. If the other write succeeds, then
3551 * we'll end up returning whatever was written. If it fails, then
3552 * we'll get a new rc value from that.
3553 */
3554 if (!list_empty(&ctx->list))
3555 rc = 0;
3556
3557 mutex_unlock(&ctx->aio_mutex);
3558
3559 if (rc) {
3560 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3561 return rc;
3562 }
3563
3564 if (!is_sync_kiocb(iocb)) {
3565 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3566 return -EIOCBQUEUED;
3567 }
3568
3569 rc = wait_for_completion_killable(&ctx->done);
3570 if (rc) {
3571 mutex_lock(&ctx->aio_mutex);
3572 ctx->rc = rc = -EINTR;
3573 total_written = ctx->total_len;
3574 mutex_unlock(&ctx->aio_mutex);
3575 } else {
3576 rc = ctx->rc;
3577 total_written = ctx->total_len;
3578 }
3579
3580 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3581
3582 if (unlikely(!total_written))
3583 return rc;
3584
3585 iocb->ki_pos += total_written;
3586 return total_written;
3587 }
3588
cifs_direct_writev(struct kiocb * iocb,struct iov_iter * from)3589 ssize_t cifs_direct_writev(struct kiocb *iocb, struct iov_iter *from)
3590 {
3591 struct file *file = iocb->ki_filp;
3592
3593 cifs_revalidate_mapping(file->f_inode);
3594 return __cifs_writev(iocb, from, true);
3595 }
3596
cifs_user_writev(struct kiocb * iocb,struct iov_iter * from)3597 ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
3598 {
3599 return __cifs_writev(iocb, from, false);
3600 }
3601
3602 static ssize_t
cifs_writev(struct kiocb * iocb,struct iov_iter * from)3603 cifs_writev(struct kiocb *iocb, struct iov_iter *from)
3604 {
3605 struct file *file = iocb->ki_filp;
3606 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
3607 struct inode *inode = file->f_mapping->host;
3608 struct cifsInodeInfo *cinode = CIFS_I(inode);
3609 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
3610 ssize_t rc;
3611
3612 inode_lock(inode);
3613 /*
3614 * We need to hold the sem to be sure nobody modifies lock list
3615 * with a brlock that prevents writing.
3616 */
3617 down_read(&cinode->lock_sem);
3618
3619 rc = generic_write_checks(iocb, from);
3620 if (rc <= 0)
3621 goto out;
3622
3623 if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(from),
3624 server->vals->exclusive_lock_type, 0,
3625 NULL, CIFS_WRITE_OP))
3626 rc = __generic_file_write_iter(iocb, from);
3627 else
3628 rc = -EACCES;
3629 out:
3630 up_read(&cinode->lock_sem);
3631 inode_unlock(inode);
3632
3633 if (rc > 0)
3634 rc = generic_write_sync(iocb, rc);
3635 return rc;
3636 }
3637
3638 ssize_t
cifs_strict_writev(struct kiocb * iocb,struct iov_iter * from)3639 cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
3640 {
3641 struct inode *inode = file_inode(iocb->ki_filp);
3642 struct cifsInodeInfo *cinode = CIFS_I(inode);
3643 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
3644 struct cifsFileInfo *cfile = (struct cifsFileInfo *)
3645 iocb->ki_filp->private_data;
3646 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
3647 ssize_t written;
3648
3649 written = cifs_get_writer(cinode);
3650 if (written)
3651 return written;
3652
3653 if (CIFS_CACHE_WRITE(cinode)) {
3654 if (cap_unix(tcon->ses) &&
3655 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
3656 && ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
3657 written = generic_file_write_iter(iocb, from);
3658 goto out;
3659 }
3660 written = cifs_writev(iocb, from);
3661 goto out;
3662 }
3663 /*
3664 * For non-oplocked files in strict cache mode we need to write the data
3665 * to the server exactly from the pos to pos+len-1 rather than flush all
3666 * affected pages because it may cause a error with mandatory locks on
3667 * these pages but not on the region from pos to ppos+len-1.
3668 */
3669 written = cifs_user_writev(iocb, from);
3670 if (CIFS_CACHE_READ(cinode)) {
3671 /*
3672 * We have read level caching and we have just sent a write
3673 * request to the server thus making data in the cache stale.
3674 * Zap the cache and set oplock/lease level to NONE to avoid
3675 * reading stale data from the cache. All subsequent read
3676 * operations will read new data from the server.
3677 */
3678 cifs_zap_mapping(inode);
3679 cifs_dbg(FYI, "Set Oplock/Lease to NONE for inode=%p after write\n",
3680 inode);
3681 cinode->oplock = 0;
3682 }
3683 out:
3684 cifs_put_writer(cinode);
3685 return written;
3686 }
3687
3688 static struct cifs_readdata *
cifs_readdata_direct_alloc(struct page ** pages,work_func_t complete)3689 cifs_readdata_direct_alloc(struct page **pages, work_func_t complete)
3690 {
3691 struct cifs_readdata *rdata;
3692
3693 rdata = kzalloc(sizeof(*rdata), GFP_KERNEL);
3694 if (rdata != NULL) {
3695 rdata->pages = pages;
3696 kref_init(&rdata->refcount);
3697 INIT_LIST_HEAD(&rdata->list);
3698 init_completion(&rdata->done);
3699 INIT_WORK(&rdata->work, complete);
3700 }
3701
3702 return rdata;
3703 }
3704
3705 static struct cifs_readdata *
cifs_readdata_alloc(unsigned int nr_pages,work_func_t complete)3706 cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete)
3707 {
3708 struct page **pages =
3709 kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
3710 struct cifs_readdata *ret = NULL;
3711
3712 if (pages) {
3713 ret = cifs_readdata_direct_alloc(pages, complete);
3714 if (!ret)
3715 kfree(pages);
3716 }
3717
3718 return ret;
3719 }
3720
3721 void
cifs_readdata_release(struct kref * refcount)3722 cifs_readdata_release(struct kref *refcount)
3723 {
3724 struct cifs_readdata *rdata = container_of(refcount,
3725 struct cifs_readdata, refcount);
3726 #ifdef CONFIG_CIFS_SMB_DIRECT
3727 if (rdata->mr) {
3728 smbd_deregister_mr(rdata->mr);
3729 rdata->mr = NULL;
3730 }
3731 #endif
3732 if (rdata->cfile)
3733 cifsFileInfo_put(rdata->cfile);
3734
3735 kvfree(rdata->pages);
3736 kfree(rdata);
3737 }
3738
3739 static int
cifs_read_allocate_pages(struct cifs_readdata * rdata,unsigned int nr_pages)3740 cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages)
3741 {
3742 int rc = 0;
3743 struct page *page;
3744 unsigned int i;
3745
3746 for (i = 0; i < nr_pages; i++) {
3747 page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
3748 if (!page) {
3749 rc = -ENOMEM;
3750 break;
3751 }
3752 rdata->pages[i] = page;
3753 }
3754
3755 if (rc) {
3756 unsigned int nr_page_failed = i;
3757
3758 for (i = 0; i < nr_page_failed; i++) {
3759 put_page(rdata->pages[i]);
3760 rdata->pages[i] = NULL;
3761 }
3762 }
3763 return rc;
3764 }
3765
3766 static void
cifs_uncached_readdata_release(struct kref * refcount)3767 cifs_uncached_readdata_release(struct kref *refcount)
3768 {
3769 struct cifs_readdata *rdata = container_of(refcount,
3770 struct cifs_readdata, refcount);
3771 unsigned int i;
3772
3773 kref_put(&rdata->ctx->refcount, cifs_aio_ctx_release);
3774 for (i = 0; i < rdata->nr_pages; i++) {
3775 put_page(rdata->pages[i]);
3776 }
3777 cifs_readdata_release(refcount);
3778 }
3779
3780 /**
3781 * cifs_readdata_to_iov - copy data from pages in response to an iovec
3782 * @rdata: the readdata response with list of pages holding data
3783 * @iter: destination for our data
3784 *
3785 * This function copies data from a list of pages in a readdata response into
3786 * an array of iovecs. It will first calculate where the data should go
3787 * based on the info in the readdata and then copy the data into that spot.
3788 */
3789 static int
cifs_readdata_to_iov(struct cifs_readdata * rdata,struct iov_iter * iter)3790 cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
3791 {
3792 size_t remaining = rdata->got_bytes;
3793 unsigned int i;
3794
3795 for (i = 0; i < rdata->nr_pages; i++) {
3796 struct page *page = rdata->pages[i];
3797 size_t copy = min_t(size_t, remaining, PAGE_SIZE);
3798 size_t written;
3799
3800 if (unlikely(iov_iter_is_pipe(iter))) {
3801 void *addr = kmap_atomic(page);
3802
3803 written = copy_to_iter(addr, copy, iter);
3804 kunmap_atomic(addr);
3805 } else
3806 written = copy_page_to_iter(page, 0, copy, iter);
3807 remaining -= written;
3808 if (written < copy && iov_iter_count(iter) > 0)
3809 break;
3810 }
3811 return remaining ? -EFAULT : 0;
3812 }
3813
3814 static void collect_uncached_read_data(struct cifs_aio_ctx *ctx);
3815
3816 static void
cifs_uncached_readv_complete(struct work_struct * work)3817 cifs_uncached_readv_complete(struct work_struct *work)
3818 {
3819 struct cifs_readdata *rdata = container_of(work,
3820 struct cifs_readdata, work);
3821
3822 complete(&rdata->done);
3823 collect_uncached_read_data(rdata->ctx);
3824 /* the below call can possibly free the last ref to aio ctx */
3825 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
3826 }
3827
3828 static int
uncached_fill_pages(struct TCP_Server_Info * server,struct cifs_readdata * rdata,struct iov_iter * iter,unsigned int len)3829 uncached_fill_pages(struct TCP_Server_Info *server,
3830 struct cifs_readdata *rdata, struct iov_iter *iter,
3831 unsigned int len)
3832 {
3833 int result = 0;
3834 unsigned int i;
3835 unsigned int nr_pages = rdata->nr_pages;
3836 unsigned int page_offset = rdata->page_offset;
3837
3838 rdata->got_bytes = 0;
3839 rdata->tailsz = PAGE_SIZE;
3840 for (i = 0; i < nr_pages; i++) {
3841 struct page *page = rdata->pages[i];
3842 size_t n;
3843 unsigned int segment_size = rdata->pagesz;
3844
3845 if (i == 0)
3846 segment_size -= page_offset;
3847 else
3848 page_offset = 0;
3849
3850
3851 if (len <= 0) {
3852 /* no need to hold page hostage */
3853 rdata->pages[i] = NULL;
3854 rdata->nr_pages--;
3855 put_page(page);
3856 continue;
3857 }
3858
3859 n = len;
3860 if (len >= segment_size)
3861 /* enough data to fill the page */
3862 n = segment_size;
3863 else
3864 rdata->tailsz = len;
3865 len -= n;
3866
3867 if (iter)
3868 result = copy_page_from_iter(
3869 page, page_offset, n, iter);
3870 #ifdef CONFIG_CIFS_SMB_DIRECT
3871 else if (rdata->mr)
3872 result = n;
3873 #endif
3874 else
3875 result = cifs_read_page_from_socket(
3876 server, page, page_offset, n);
3877 if (result < 0)
3878 break;
3879
3880 rdata->got_bytes += result;
3881 }
3882
3883 return rdata->got_bytes > 0 && result != -ECONNABORTED ?
3884 rdata->got_bytes : result;
3885 }
3886
3887 static int
cifs_uncached_read_into_pages(struct TCP_Server_Info * server,struct cifs_readdata * rdata,unsigned int len)3888 cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
3889 struct cifs_readdata *rdata, unsigned int len)
3890 {
3891 return uncached_fill_pages(server, rdata, NULL, len);
3892 }
3893
3894 static int
cifs_uncached_copy_into_pages(struct TCP_Server_Info * server,struct cifs_readdata * rdata,struct iov_iter * iter)3895 cifs_uncached_copy_into_pages(struct TCP_Server_Info *server,
3896 struct cifs_readdata *rdata,
3897 struct iov_iter *iter)
3898 {
3899 return uncached_fill_pages(server, rdata, iter, iter->count);
3900 }
3901
cifs_resend_rdata(struct cifs_readdata * rdata,struct list_head * rdata_list,struct cifs_aio_ctx * ctx)3902 static int cifs_resend_rdata(struct cifs_readdata *rdata,
3903 struct list_head *rdata_list,
3904 struct cifs_aio_ctx *ctx)
3905 {
3906 unsigned int rsize;
3907 struct cifs_credits credits;
3908 int rc;
3909 struct TCP_Server_Info *server;
3910
3911 /* XXX: should we pick a new channel here? */
3912 server = rdata->server;
3913
3914 do {
3915 if (rdata->cfile->invalidHandle) {
3916 rc = cifs_reopen_file(rdata->cfile, true);
3917 if (rc == -EAGAIN)
3918 continue;
3919 else if (rc)
3920 break;
3921 }
3922
3923 /*
3924 * Wait for credits to resend this rdata.
3925 * Note: we are attempting to resend the whole rdata not in
3926 * segments
3927 */
3928 do {
3929 rc = server->ops->wait_mtu_credits(server, rdata->bytes,
3930 &rsize, &credits);
3931
3932 if (rc)
3933 goto fail;
3934
3935 if (rsize < rdata->bytes) {
3936 add_credits_and_wake_if(server, &credits, 0);
3937 msleep(1000);
3938 }
3939 } while (rsize < rdata->bytes);
3940 rdata->credits = credits;
3941
3942 rc = adjust_credits(server, &rdata->credits, rdata->bytes);
3943 if (!rc) {
3944 if (rdata->cfile->invalidHandle)
3945 rc = -EAGAIN;
3946 else {
3947 #ifdef CONFIG_CIFS_SMB_DIRECT
3948 if (rdata->mr) {
3949 rdata->mr->need_invalidate = true;
3950 smbd_deregister_mr(rdata->mr);
3951 rdata->mr = NULL;
3952 }
3953 #endif
3954 rc = server->ops->async_readv(rdata);
3955 }
3956 }
3957
3958 /* If the read was successfully sent, we are done */
3959 if (!rc) {
3960 /* Add to aio pending list */
3961 list_add_tail(&rdata->list, rdata_list);
3962 return 0;
3963 }
3964
3965 /* Roll back credits and retry if needed */
3966 add_credits_and_wake_if(server, &rdata->credits, 0);
3967 } while (rc == -EAGAIN);
3968
3969 fail:
3970 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
3971 return rc;
3972 }
3973
3974 static int
cifs_send_async_read(loff_t offset,size_t len,struct cifsFileInfo * open_file,struct cifs_sb_info * cifs_sb,struct list_head * rdata_list,struct cifs_aio_ctx * ctx)3975 cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
3976 struct cifs_sb_info *cifs_sb, struct list_head *rdata_list,
3977 struct cifs_aio_ctx *ctx)
3978 {
3979 struct cifs_readdata *rdata;
3980 unsigned int npages, rsize;
3981 struct cifs_credits credits_on_stack;
3982 struct cifs_credits *credits = &credits_on_stack;
3983 size_t cur_len;
3984 int rc;
3985 pid_t pid;
3986 struct TCP_Server_Info *server;
3987 struct page **pagevec;
3988 size_t start;
3989 struct iov_iter direct_iov = ctx->iter;
3990
3991 server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
3992
3993 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3994 pid = open_file->pid;
3995 else
3996 pid = current->tgid;
3997
3998 if (ctx->direct_io)
3999 iov_iter_advance(&direct_iov, offset - ctx->pos);
4000
4001 do {
4002 if (open_file->invalidHandle) {
4003 rc = cifs_reopen_file(open_file, true);
4004 if (rc == -EAGAIN)
4005 continue;
4006 else if (rc)
4007 break;
4008 }
4009
4010 if (cifs_sb->ctx->rsize == 0)
4011 cifs_sb->ctx->rsize =
4012 server->ops->negotiate_rsize(tlink_tcon(open_file->tlink),
4013 cifs_sb->ctx);
4014
4015 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
4016 &rsize, credits);
4017 if (rc)
4018 break;
4019
4020 cur_len = min_t(const size_t, len, rsize);
4021
4022 if (ctx->direct_io) {
4023 ssize_t result;
4024
4025 result = iov_iter_get_pages_alloc2(
4026 &direct_iov, &pagevec,
4027 cur_len, &start);
4028 if (result < 0) {
4029 cifs_dbg(VFS,
4030 "Couldn't get user pages (rc=%zd) iter type %d iov_offset %zd count %zd\n",
4031 result, iov_iter_type(&direct_iov),
4032 direct_iov.iov_offset,
4033 direct_iov.count);
4034 dump_stack();
4035
4036 rc = result;
4037 add_credits_and_wake_if(server, credits, 0);
4038 break;
4039 }
4040 cur_len = (size_t)result;
4041
4042 rdata = cifs_readdata_direct_alloc(
4043 pagevec, cifs_uncached_readv_complete);
4044 if (!rdata) {
4045 add_credits_and_wake_if(server, credits, 0);
4046 rc = -ENOMEM;
4047 break;
4048 }
4049
4050 npages = (cur_len + start + PAGE_SIZE-1) / PAGE_SIZE;
4051 rdata->page_offset = start;
4052 rdata->tailsz = npages > 1 ?
4053 cur_len-(PAGE_SIZE-start)-(npages-2)*PAGE_SIZE :
4054 cur_len;
4055
4056 } else {
4057
4058 npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
4059 /* allocate a readdata struct */
4060 rdata = cifs_readdata_alloc(npages,
4061 cifs_uncached_readv_complete);
4062 if (!rdata) {
4063 add_credits_and_wake_if(server, credits, 0);
4064 rc = -ENOMEM;
4065 break;
4066 }
4067
4068 rc = cifs_read_allocate_pages(rdata, npages);
4069 if (rc) {
4070 kvfree(rdata->pages);
4071 kfree(rdata);
4072 add_credits_and_wake_if(server, credits, 0);
4073 break;
4074 }
4075
4076 rdata->tailsz = PAGE_SIZE;
4077 }
4078
4079 rdata->server = server;
4080 rdata->cfile = cifsFileInfo_get(open_file);
4081 rdata->nr_pages = npages;
4082 rdata->offset = offset;
4083 rdata->bytes = cur_len;
4084 rdata->pid = pid;
4085 rdata->pagesz = PAGE_SIZE;
4086 rdata->read_into_pages = cifs_uncached_read_into_pages;
4087 rdata->copy_into_pages = cifs_uncached_copy_into_pages;
4088 rdata->credits = credits_on_stack;
4089 rdata->ctx = ctx;
4090 kref_get(&ctx->refcount);
4091
4092 rc = adjust_credits(server, &rdata->credits, rdata->bytes);
4093
4094 if (!rc) {
4095 if (rdata->cfile->invalidHandle)
4096 rc = -EAGAIN;
4097 else
4098 rc = server->ops->async_readv(rdata);
4099 }
4100
4101 if (rc) {
4102 add_credits_and_wake_if(server, &rdata->credits, 0);
4103 kref_put(&rdata->refcount,
4104 cifs_uncached_readdata_release);
4105 if (rc == -EAGAIN) {
4106 iov_iter_revert(&direct_iov, cur_len);
4107 continue;
4108 }
4109 break;
4110 }
4111
4112 list_add_tail(&rdata->list, rdata_list);
4113 offset += cur_len;
4114 len -= cur_len;
4115 } while (len > 0);
4116
4117 return rc;
4118 }
4119
4120 static void
collect_uncached_read_data(struct cifs_aio_ctx * ctx)4121 collect_uncached_read_data(struct cifs_aio_ctx *ctx)
4122 {
4123 struct cifs_readdata *rdata, *tmp;
4124 struct iov_iter *to = &ctx->iter;
4125 struct cifs_sb_info *cifs_sb;
4126 int rc;
4127
4128 cifs_sb = CIFS_SB(ctx->cfile->dentry->d_sb);
4129
4130 mutex_lock(&ctx->aio_mutex);
4131
4132 if (list_empty(&ctx->list)) {
4133 mutex_unlock(&ctx->aio_mutex);
4134 return;
4135 }
4136
4137 rc = ctx->rc;
4138 /* the loop below should proceed in the order of increasing offsets */
4139 again:
4140 list_for_each_entry_safe(rdata, tmp, &ctx->list, list) {
4141 if (!rc) {
4142 if (!try_wait_for_completion(&rdata->done)) {
4143 mutex_unlock(&ctx->aio_mutex);
4144 return;
4145 }
4146
4147 if (rdata->result == -EAGAIN) {
4148 /* resend call if it's a retryable error */
4149 struct list_head tmp_list;
4150 unsigned int got_bytes = rdata->got_bytes;
4151
4152 list_del_init(&rdata->list);
4153 INIT_LIST_HEAD(&tmp_list);
4154
4155 /*
4156 * Got a part of data and then reconnect has
4157 * happened -- fill the buffer and continue
4158 * reading.
4159 */
4160 if (got_bytes && got_bytes < rdata->bytes) {
4161 rc = 0;
4162 if (!ctx->direct_io)
4163 rc = cifs_readdata_to_iov(rdata, to);
4164 if (rc) {
4165 kref_put(&rdata->refcount,
4166 cifs_uncached_readdata_release);
4167 continue;
4168 }
4169 }
4170
4171 if (ctx->direct_io) {
4172 /*
4173 * Re-use rdata as this is a
4174 * direct I/O
4175 */
4176 rc = cifs_resend_rdata(
4177 rdata,
4178 &tmp_list, ctx);
4179 } else {
4180 rc = cifs_send_async_read(
4181 rdata->offset + got_bytes,
4182 rdata->bytes - got_bytes,
4183 rdata->cfile, cifs_sb,
4184 &tmp_list, ctx);
4185
4186 kref_put(&rdata->refcount,
4187 cifs_uncached_readdata_release);
4188 }
4189
4190 list_splice(&tmp_list, &ctx->list);
4191
4192 goto again;
4193 } else if (rdata->result)
4194 rc = rdata->result;
4195 else if (!ctx->direct_io)
4196 rc = cifs_readdata_to_iov(rdata, to);
4197
4198 /* if there was a short read -- discard anything left */
4199 if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
4200 rc = -ENODATA;
4201
4202 ctx->total_len += rdata->got_bytes;
4203 }
4204 list_del_init(&rdata->list);
4205 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
4206 }
4207
4208 if (!ctx->direct_io)
4209 ctx->total_len = ctx->len - iov_iter_count(to);
4210
4211 /* mask nodata case */
4212 if (rc == -ENODATA)
4213 rc = 0;
4214
4215 ctx->rc = (rc == 0) ? (ssize_t)ctx->total_len : rc;
4216
4217 mutex_unlock(&ctx->aio_mutex);
4218
4219 if (ctx->iocb && ctx->iocb->ki_complete)
4220 ctx->iocb->ki_complete(ctx->iocb, ctx->rc);
4221 else
4222 complete(&ctx->done);
4223 }
4224
__cifs_readv(struct kiocb * iocb,struct iov_iter * to,bool direct)4225 static ssize_t __cifs_readv(
4226 struct kiocb *iocb, struct iov_iter *to, bool direct)
4227 {
4228 size_t len;
4229 struct file *file = iocb->ki_filp;
4230 struct cifs_sb_info *cifs_sb;
4231 struct cifsFileInfo *cfile;
4232 struct cifs_tcon *tcon;
4233 ssize_t rc, total_read = 0;
4234 loff_t offset = iocb->ki_pos;
4235 struct cifs_aio_ctx *ctx;
4236
4237 /*
4238 * iov_iter_get_pages_alloc() doesn't work with ITER_KVEC,
4239 * fall back to data copy read path
4240 * this could be improved by getting pages directly in ITER_KVEC
4241 */
4242 if (direct && iov_iter_is_kvec(to)) {
4243 cifs_dbg(FYI, "use non-direct cifs_user_readv for kvec I/O\n");
4244 direct = false;
4245 }
4246
4247 len = iov_iter_count(to);
4248 if (!len)
4249 return 0;
4250
4251 cifs_sb = CIFS_FILE_SB(file);
4252 cfile = file->private_data;
4253 tcon = tlink_tcon(cfile->tlink);
4254
4255 if (!tcon->ses->server->ops->async_readv)
4256 return -ENOSYS;
4257
4258 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
4259 cifs_dbg(FYI, "attempting read on write only file instance\n");
4260
4261 ctx = cifs_aio_ctx_alloc();
4262 if (!ctx)
4263 return -ENOMEM;
4264
4265 ctx->cfile = cifsFileInfo_get(cfile);
4266
4267 if (!is_sync_kiocb(iocb))
4268 ctx->iocb = iocb;
4269
4270 if (user_backed_iter(to))
4271 ctx->should_dirty = true;
4272
4273 if (direct) {
4274 ctx->pos = offset;
4275 ctx->direct_io = true;
4276 ctx->iter = *to;
4277 ctx->len = len;
4278 } else {
4279 rc = setup_aio_ctx_iter(ctx, to, READ);
4280 if (rc) {
4281 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4282 return rc;
4283 }
4284 len = ctx->len;
4285 }
4286
4287 if (direct) {
4288 rc = filemap_write_and_wait_range(file->f_inode->i_mapping,
4289 offset, offset + len - 1);
4290 if (rc) {
4291 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4292 return -EAGAIN;
4293 }
4294 }
4295
4296 /* grab a lock here due to read response handlers can access ctx */
4297 mutex_lock(&ctx->aio_mutex);
4298
4299 rc = cifs_send_async_read(offset, len, cfile, cifs_sb, &ctx->list, ctx);
4300
4301 /* if at least one read request send succeeded, then reset rc */
4302 if (!list_empty(&ctx->list))
4303 rc = 0;
4304
4305 mutex_unlock(&ctx->aio_mutex);
4306
4307 if (rc) {
4308 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4309 return rc;
4310 }
4311
4312 if (!is_sync_kiocb(iocb)) {
4313 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4314 return -EIOCBQUEUED;
4315 }
4316
4317 rc = wait_for_completion_killable(&ctx->done);
4318 if (rc) {
4319 mutex_lock(&ctx->aio_mutex);
4320 ctx->rc = rc = -EINTR;
4321 total_read = ctx->total_len;
4322 mutex_unlock(&ctx->aio_mutex);
4323 } else {
4324 rc = ctx->rc;
4325 total_read = ctx->total_len;
4326 }
4327
4328 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4329
4330 if (total_read) {
4331 iocb->ki_pos += total_read;
4332 return total_read;
4333 }
4334 return rc;
4335 }
4336
cifs_direct_readv(struct kiocb * iocb,struct iov_iter * to)4337 ssize_t cifs_direct_readv(struct kiocb *iocb, struct iov_iter *to)
4338 {
4339 return __cifs_readv(iocb, to, true);
4340 }
4341
cifs_user_readv(struct kiocb * iocb,struct iov_iter * to)4342 ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
4343 {
4344 return __cifs_readv(iocb, to, false);
4345 }
4346
4347 ssize_t
cifs_strict_readv(struct kiocb * iocb,struct iov_iter * to)4348 cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
4349 {
4350 struct inode *inode = file_inode(iocb->ki_filp);
4351 struct cifsInodeInfo *cinode = CIFS_I(inode);
4352 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
4353 struct cifsFileInfo *cfile = (struct cifsFileInfo *)
4354 iocb->ki_filp->private_data;
4355 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
4356 int rc = -EACCES;
4357
4358 /*
4359 * In strict cache mode we need to read from the server all the time
4360 * if we don't have level II oplock because the server can delay mtime
4361 * change - so we can't make a decision about inode invalidating.
4362 * And we can also fail with pagereading if there are mandatory locks
4363 * on pages affected by this read but not on the region from pos to
4364 * pos+len-1.
4365 */
4366 if (!CIFS_CACHE_READ(cinode))
4367 return cifs_user_readv(iocb, to);
4368
4369 if (cap_unix(tcon->ses) &&
4370 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
4371 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
4372 return generic_file_read_iter(iocb, to);
4373
4374 /*
4375 * We need to hold the sem to be sure nobody modifies lock list
4376 * with a brlock that prevents reading.
4377 */
4378 down_read(&cinode->lock_sem);
4379 if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(to),
4380 tcon->ses->server->vals->shared_lock_type,
4381 0, NULL, CIFS_READ_OP))
4382 rc = generic_file_read_iter(iocb, to);
4383 up_read(&cinode->lock_sem);
4384 return rc;
4385 }
4386
4387 static ssize_t
cifs_read(struct file * file,char * read_data,size_t read_size,loff_t * offset)4388 cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
4389 {
4390 int rc = -EACCES;
4391 unsigned int bytes_read = 0;
4392 unsigned int total_read;
4393 unsigned int current_read_size;
4394 unsigned int rsize;
4395 struct cifs_sb_info *cifs_sb;
4396 struct cifs_tcon *tcon;
4397 struct TCP_Server_Info *server;
4398 unsigned int xid;
4399 char *cur_offset;
4400 struct cifsFileInfo *open_file;
4401 struct cifs_io_parms io_parms = {0};
4402 int buf_type = CIFS_NO_BUFFER;
4403 __u32 pid;
4404
4405 xid = get_xid();
4406 cifs_sb = CIFS_FILE_SB(file);
4407
4408 /* FIXME: set up handlers for larger reads and/or convert to async */
4409 rsize = min_t(unsigned int, cifs_sb->ctx->rsize, CIFSMaxBufSize);
4410
4411 if (file->private_data == NULL) {
4412 rc = -EBADF;
4413 free_xid(xid);
4414 return rc;
4415 }
4416 open_file = file->private_data;
4417 tcon = tlink_tcon(open_file->tlink);
4418 server = cifs_pick_channel(tcon->ses);
4419
4420 if (!server->ops->sync_read) {
4421 free_xid(xid);
4422 return -ENOSYS;
4423 }
4424
4425 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
4426 pid = open_file->pid;
4427 else
4428 pid = current->tgid;
4429
4430 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
4431 cifs_dbg(FYI, "attempting read on write only file instance\n");
4432
4433 for (total_read = 0, cur_offset = read_data; read_size > total_read;
4434 total_read += bytes_read, cur_offset += bytes_read) {
4435 do {
4436 current_read_size = min_t(uint, read_size - total_read,
4437 rsize);
4438 /*
4439 * For windows me and 9x we do not want to request more
4440 * than it negotiated since it will refuse the read
4441 * then.
4442 */
4443 if (!(tcon->ses->capabilities &
4444 tcon->ses->server->vals->cap_large_files)) {
4445 current_read_size = min_t(uint,
4446 current_read_size, CIFSMaxBufSize);
4447 }
4448 if (open_file->invalidHandle) {
4449 rc = cifs_reopen_file(open_file, true);
4450 if (rc != 0)
4451 break;
4452 }
4453 io_parms.pid = pid;
4454 io_parms.tcon = tcon;
4455 io_parms.offset = *offset;
4456 io_parms.length = current_read_size;
4457 io_parms.server = server;
4458 rc = server->ops->sync_read(xid, &open_file->fid, &io_parms,
4459 &bytes_read, &cur_offset,
4460 &buf_type);
4461 } while (rc == -EAGAIN);
4462
4463 if (rc || (bytes_read == 0)) {
4464 if (total_read) {
4465 break;
4466 } else {
4467 free_xid(xid);
4468 return rc;
4469 }
4470 } else {
4471 cifs_stats_bytes_read(tcon, total_read);
4472 *offset += bytes_read;
4473 }
4474 }
4475 free_xid(xid);
4476 return total_read;
4477 }
4478
4479 /*
4480 * If the page is mmap'ed into a process' page tables, then we need to make
4481 * sure that it doesn't change while being written back.
4482 */
4483 static vm_fault_t
cifs_page_mkwrite(struct vm_fault * vmf)4484 cifs_page_mkwrite(struct vm_fault *vmf)
4485 {
4486 struct page *page = vmf->page;
4487
4488 /* Wait for the page to be written to the cache before we allow it to
4489 * be modified. We then assume the entire page will need writing back.
4490 */
4491 #ifdef CONFIG_CIFS_FSCACHE
4492 if (PageFsCache(page) &&
4493 wait_on_page_fscache_killable(page) < 0)
4494 return VM_FAULT_RETRY;
4495 #endif
4496
4497 wait_on_page_writeback(page);
4498
4499 if (lock_page_killable(page) < 0)
4500 return VM_FAULT_RETRY;
4501 return VM_FAULT_LOCKED;
4502 }
4503
4504 static const struct vm_operations_struct cifs_file_vm_ops = {
4505 .fault = filemap_fault,
4506 .map_pages = filemap_map_pages,
4507 .page_mkwrite = cifs_page_mkwrite,
4508 };
4509
cifs_file_strict_mmap(struct file * file,struct vm_area_struct * vma)4510 int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
4511 {
4512 int xid, rc = 0;
4513 struct inode *inode = file_inode(file);
4514
4515 xid = get_xid();
4516
4517 if (!CIFS_CACHE_READ(CIFS_I(inode)))
4518 rc = cifs_zap_mapping(inode);
4519 if (!rc)
4520 rc = generic_file_mmap(file, vma);
4521 if (!rc)
4522 vma->vm_ops = &cifs_file_vm_ops;
4523
4524 free_xid(xid);
4525 return rc;
4526 }
4527
cifs_file_mmap(struct file * file,struct vm_area_struct * vma)4528 int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
4529 {
4530 int rc, xid;
4531
4532 xid = get_xid();
4533
4534 rc = cifs_revalidate_file(file);
4535 if (rc)
4536 cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
4537 rc);
4538 if (!rc)
4539 rc = generic_file_mmap(file, vma);
4540 if (!rc)
4541 vma->vm_ops = &cifs_file_vm_ops;
4542
4543 free_xid(xid);
4544 return rc;
4545 }
4546
4547 static void
cifs_readv_complete(struct work_struct * work)4548 cifs_readv_complete(struct work_struct *work)
4549 {
4550 unsigned int i, got_bytes;
4551 struct cifs_readdata *rdata = container_of(work,
4552 struct cifs_readdata, work);
4553
4554 got_bytes = rdata->got_bytes;
4555 for (i = 0; i < rdata->nr_pages; i++) {
4556 struct page *page = rdata->pages[i];
4557
4558 if (rdata->result == 0 ||
4559 (rdata->result == -EAGAIN && got_bytes)) {
4560 flush_dcache_page(page);
4561 SetPageUptodate(page);
4562 } else
4563 SetPageError(page);
4564
4565 if (rdata->result == 0 ||
4566 (rdata->result == -EAGAIN && got_bytes))
4567 cifs_readpage_to_fscache(rdata->mapping->host, page);
4568
4569 unlock_page(page);
4570
4571 got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
4572
4573 put_page(page);
4574 rdata->pages[i] = NULL;
4575 }
4576 kref_put(&rdata->refcount, cifs_readdata_release);
4577 }
4578
4579 static int
readpages_fill_pages(struct TCP_Server_Info * server,struct cifs_readdata * rdata,struct iov_iter * iter,unsigned int len)4580 readpages_fill_pages(struct TCP_Server_Info *server,
4581 struct cifs_readdata *rdata, struct iov_iter *iter,
4582 unsigned int len)
4583 {
4584 int result = 0;
4585 unsigned int i;
4586 u64 eof;
4587 pgoff_t eof_index;
4588 unsigned int nr_pages = rdata->nr_pages;
4589 unsigned int page_offset = rdata->page_offset;
4590
4591 /* determine the eof that the server (probably) has */
4592 eof = CIFS_I(rdata->mapping->host)->server_eof;
4593 eof_index = eof ? (eof - 1) >> PAGE_SHIFT : 0;
4594 cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
4595
4596 rdata->got_bytes = 0;
4597 rdata->tailsz = PAGE_SIZE;
4598 for (i = 0; i < nr_pages; i++) {
4599 struct page *page = rdata->pages[i];
4600 unsigned int to_read = rdata->pagesz;
4601 size_t n;
4602
4603 if (i == 0)
4604 to_read -= page_offset;
4605 else
4606 page_offset = 0;
4607
4608 n = to_read;
4609
4610 if (len >= to_read) {
4611 len -= to_read;
4612 } else if (len > 0) {
4613 /* enough for partial page, fill and zero the rest */
4614 zero_user(page, len + page_offset, to_read - len);
4615 n = rdata->tailsz = len;
4616 len = 0;
4617 } else if (page->index > eof_index) {
4618 /*
4619 * The VFS will not try to do readahead past the
4620 * i_size, but it's possible that we have outstanding
4621 * writes with gaps in the middle and the i_size hasn't
4622 * caught up yet. Populate those with zeroed out pages
4623 * to prevent the VFS from repeatedly attempting to
4624 * fill them until the writes are flushed.
4625 */
4626 zero_user(page, 0, PAGE_SIZE);
4627 flush_dcache_page(page);
4628 SetPageUptodate(page);
4629 unlock_page(page);
4630 put_page(page);
4631 rdata->pages[i] = NULL;
4632 rdata->nr_pages--;
4633 continue;
4634 } else {
4635 /* no need to hold page hostage */
4636 unlock_page(page);
4637 put_page(page);
4638 rdata->pages[i] = NULL;
4639 rdata->nr_pages--;
4640 continue;
4641 }
4642
4643 if (iter)
4644 result = copy_page_from_iter(
4645 page, page_offset, n, iter);
4646 #ifdef CONFIG_CIFS_SMB_DIRECT
4647 else if (rdata->mr)
4648 result = n;
4649 #endif
4650 else
4651 result = cifs_read_page_from_socket(
4652 server, page, page_offset, n);
4653 if (result < 0)
4654 break;
4655
4656 rdata->got_bytes += result;
4657 }
4658
4659 return rdata->got_bytes > 0 && result != -ECONNABORTED ?
4660 rdata->got_bytes : result;
4661 }
4662
4663 static int
cifs_readpages_read_into_pages(struct TCP_Server_Info * server,struct cifs_readdata * rdata,unsigned int len)4664 cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
4665 struct cifs_readdata *rdata, unsigned int len)
4666 {
4667 return readpages_fill_pages(server, rdata, NULL, len);
4668 }
4669
4670 static int
cifs_readpages_copy_into_pages(struct TCP_Server_Info * server,struct cifs_readdata * rdata,struct iov_iter * iter)4671 cifs_readpages_copy_into_pages(struct TCP_Server_Info *server,
4672 struct cifs_readdata *rdata,
4673 struct iov_iter *iter)
4674 {
4675 return readpages_fill_pages(server, rdata, iter, iter->count);
4676 }
4677
cifs_readahead(struct readahead_control * ractl)4678 static void cifs_readahead(struct readahead_control *ractl)
4679 {
4680 int rc;
4681 struct cifsFileInfo *open_file = ractl->file->private_data;
4682 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(ractl->file);
4683 struct TCP_Server_Info *server;
4684 pid_t pid;
4685 unsigned int xid, nr_pages, last_batch_size = 0, cache_nr_pages = 0;
4686 pgoff_t next_cached = ULONG_MAX;
4687 bool caching = fscache_cookie_enabled(cifs_inode_cookie(ractl->mapping->host)) &&
4688 cifs_inode_cookie(ractl->mapping->host)->cache_priv;
4689 bool check_cache = caching;
4690
4691 xid = get_xid();
4692
4693 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
4694 pid = open_file->pid;
4695 else
4696 pid = current->tgid;
4697
4698 rc = 0;
4699 server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
4700
4701 cifs_dbg(FYI, "%s: file=%p mapping=%p num_pages=%u\n",
4702 __func__, ractl->file, ractl->mapping, readahead_count(ractl));
4703
4704 /*
4705 * Chop the readahead request up into rsize-sized read requests.
4706 */
4707 while ((nr_pages = readahead_count(ractl) - last_batch_size)) {
4708 unsigned int i, got, rsize;
4709 struct page *page;
4710 struct cifs_readdata *rdata;
4711 struct cifs_credits credits_on_stack;
4712 struct cifs_credits *credits = &credits_on_stack;
4713 pgoff_t index = readahead_index(ractl) + last_batch_size;
4714
4715 /*
4716 * Find out if we have anything cached in the range of
4717 * interest, and if so, where the next chunk of cached data is.
4718 */
4719 if (caching) {
4720 if (check_cache) {
4721 rc = cifs_fscache_query_occupancy(
4722 ractl->mapping->host, index, nr_pages,
4723 &next_cached, &cache_nr_pages);
4724 if (rc < 0)
4725 caching = false;
4726 check_cache = false;
4727 }
4728
4729 if (index == next_cached) {
4730 /*
4731 * TODO: Send a whole batch of pages to be read
4732 * by the cache.
4733 */
4734 struct folio *folio = readahead_folio(ractl);
4735
4736 last_batch_size = folio_nr_pages(folio);
4737 if (cifs_readpage_from_fscache(ractl->mapping->host,
4738 &folio->page) < 0) {
4739 /*
4740 * TODO: Deal with cache read failure
4741 * here, but for the moment, delegate
4742 * that to readpage.
4743 */
4744 caching = false;
4745 }
4746 folio_unlock(folio);
4747 next_cached++;
4748 cache_nr_pages--;
4749 if (cache_nr_pages == 0)
4750 check_cache = true;
4751 continue;
4752 }
4753 }
4754
4755 if (open_file->invalidHandle) {
4756 rc = cifs_reopen_file(open_file, true);
4757 if (rc) {
4758 if (rc == -EAGAIN)
4759 continue;
4760 break;
4761 }
4762 }
4763
4764 if (cifs_sb->ctx->rsize == 0)
4765 cifs_sb->ctx->rsize =
4766 server->ops->negotiate_rsize(tlink_tcon(open_file->tlink),
4767 cifs_sb->ctx);
4768
4769 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
4770 &rsize, credits);
4771 if (rc)
4772 break;
4773 nr_pages = min_t(size_t, rsize / PAGE_SIZE, readahead_count(ractl));
4774 nr_pages = min_t(size_t, nr_pages, next_cached - index);
4775
4776 /*
4777 * Give up immediately if rsize is too small to read an entire
4778 * page. The VFS will fall back to readpage. We should never
4779 * reach this point however since we set ra_pages to 0 when the
4780 * rsize is smaller than a cache page.
4781 */
4782 if (unlikely(!nr_pages)) {
4783 add_credits_and_wake_if(server, credits, 0);
4784 break;
4785 }
4786
4787 rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
4788 if (!rdata) {
4789 /* best to give up if we're out of mem */
4790 add_credits_and_wake_if(server, credits, 0);
4791 break;
4792 }
4793
4794 got = __readahead_batch(ractl, rdata->pages, nr_pages);
4795 if (got != nr_pages) {
4796 pr_warn("__readahead_batch() returned %u/%u\n",
4797 got, nr_pages);
4798 nr_pages = got;
4799 }
4800
4801 rdata->nr_pages = nr_pages;
4802 rdata->bytes = readahead_batch_length(ractl);
4803 rdata->cfile = cifsFileInfo_get(open_file);
4804 rdata->server = server;
4805 rdata->mapping = ractl->mapping;
4806 rdata->offset = readahead_pos(ractl);
4807 rdata->pid = pid;
4808 rdata->pagesz = PAGE_SIZE;
4809 rdata->tailsz = PAGE_SIZE;
4810 rdata->read_into_pages = cifs_readpages_read_into_pages;
4811 rdata->copy_into_pages = cifs_readpages_copy_into_pages;
4812 rdata->credits = credits_on_stack;
4813
4814 rc = adjust_credits(server, &rdata->credits, rdata->bytes);
4815 if (!rc) {
4816 if (rdata->cfile->invalidHandle)
4817 rc = -EAGAIN;
4818 else
4819 rc = server->ops->async_readv(rdata);
4820 }
4821
4822 if (rc) {
4823 add_credits_and_wake_if(server, &rdata->credits, 0);
4824 for (i = 0; i < rdata->nr_pages; i++) {
4825 page = rdata->pages[i];
4826 unlock_page(page);
4827 put_page(page);
4828 }
4829 /* Fallback to the readpage in error/reconnect cases */
4830 kref_put(&rdata->refcount, cifs_readdata_release);
4831 break;
4832 }
4833
4834 kref_put(&rdata->refcount, cifs_readdata_release);
4835 last_batch_size = nr_pages;
4836 }
4837
4838 free_xid(xid);
4839 }
4840
4841 /*
4842 * cifs_readpage_worker must be called with the page pinned
4843 */
cifs_readpage_worker(struct file * file,struct page * page,loff_t * poffset)4844 static int cifs_readpage_worker(struct file *file, struct page *page,
4845 loff_t *poffset)
4846 {
4847 char *read_data;
4848 int rc;
4849
4850 /* Is the page cached? */
4851 rc = cifs_readpage_from_fscache(file_inode(file), page);
4852 if (rc == 0)
4853 goto read_complete;
4854
4855 read_data = kmap(page);
4856 /* for reads over a certain size could initiate async read ahead */
4857
4858 rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
4859
4860 if (rc < 0)
4861 goto io_error;
4862 else
4863 cifs_dbg(FYI, "Bytes read %d\n", rc);
4864
4865 /* we do not want atime to be less than mtime, it broke some apps */
4866 file_inode(file)->i_atime = current_time(file_inode(file));
4867 if (timespec64_compare(&(file_inode(file)->i_atime), &(file_inode(file)->i_mtime)))
4868 file_inode(file)->i_atime = file_inode(file)->i_mtime;
4869 else
4870 file_inode(file)->i_atime = current_time(file_inode(file));
4871
4872 if (PAGE_SIZE > rc)
4873 memset(read_data + rc, 0, PAGE_SIZE - rc);
4874
4875 flush_dcache_page(page);
4876 SetPageUptodate(page);
4877
4878 /* send this page to the cache */
4879 cifs_readpage_to_fscache(file_inode(file), page);
4880
4881 rc = 0;
4882
4883 io_error:
4884 kunmap(page);
4885 unlock_page(page);
4886
4887 read_complete:
4888 return rc;
4889 }
4890
cifs_read_folio(struct file * file,struct folio * folio)4891 static int cifs_read_folio(struct file *file, struct folio *folio)
4892 {
4893 struct page *page = &folio->page;
4894 loff_t offset = page_file_offset(page);
4895 int rc = -EACCES;
4896 unsigned int xid;
4897
4898 xid = get_xid();
4899
4900 if (file->private_data == NULL) {
4901 rc = -EBADF;
4902 free_xid(xid);
4903 return rc;
4904 }
4905
4906 cifs_dbg(FYI, "read_folio %p at offset %d 0x%x\n",
4907 page, (int)offset, (int)offset);
4908
4909 rc = cifs_readpage_worker(file, page, &offset);
4910
4911 free_xid(xid);
4912 return rc;
4913 }
4914
is_inode_writable(struct cifsInodeInfo * cifs_inode)4915 static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
4916 {
4917 struct cifsFileInfo *open_file;
4918
4919 spin_lock(&cifs_inode->open_file_lock);
4920 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
4921 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
4922 spin_unlock(&cifs_inode->open_file_lock);
4923 return 1;
4924 }
4925 }
4926 spin_unlock(&cifs_inode->open_file_lock);
4927 return 0;
4928 }
4929
4930 /* We do not want to update the file size from server for inodes
4931 open for write - to avoid races with writepage extending
4932 the file - in the future we could consider allowing
4933 refreshing the inode only on increases in the file size
4934 but this is tricky to do without racing with writebehind
4935 page caching in the current Linux kernel design */
is_size_safe_to_change(struct cifsInodeInfo * cifsInode,__u64 end_of_file)4936 bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
4937 {
4938 if (!cifsInode)
4939 return true;
4940
4941 if (is_inode_writable(cifsInode)) {
4942 /* This inode is open for write at least once */
4943 struct cifs_sb_info *cifs_sb;
4944
4945 cifs_sb = CIFS_SB(cifsInode->netfs.inode.i_sb);
4946 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
4947 /* since no page cache to corrupt on directio
4948 we can change size safely */
4949 return true;
4950 }
4951
4952 if (i_size_read(&cifsInode->netfs.inode) < end_of_file)
4953 return true;
4954
4955 return false;
4956 } else
4957 return true;
4958 }
4959
cifs_write_begin(struct file * file,struct address_space * mapping,loff_t pos,unsigned len,struct page ** pagep,void ** fsdata)4960 static int cifs_write_begin(struct file *file, struct address_space *mapping,
4961 loff_t pos, unsigned len,
4962 struct page **pagep, void **fsdata)
4963 {
4964 int oncethru = 0;
4965 pgoff_t index = pos >> PAGE_SHIFT;
4966 loff_t offset = pos & (PAGE_SIZE - 1);
4967 loff_t page_start = pos & PAGE_MASK;
4968 loff_t i_size;
4969 struct page *page;
4970 int rc = 0;
4971
4972 cifs_dbg(FYI, "write_begin from %lld len %d\n", (long long)pos, len);
4973
4974 start:
4975 page = grab_cache_page_write_begin(mapping, index);
4976 if (!page) {
4977 rc = -ENOMEM;
4978 goto out;
4979 }
4980
4981 if (PageUptodate(page))
4982 goto out;
4983
4984 /*
4985 * If we write a full page it will be up to date, no need to read from
4986 * the server. If the write is short, we'll end up doing a sync write
4987 * instead.
4988 */
4989 if (len == PAGE_SIZE)
4990 goto out;
4991
4992 /*
4993 * optimize away the read when we have an oplock, and we're not
4994 * expecting to use any of the data we'd be reading in. That
4995 * is, when the page lies beyond the EOF, or straddles the EOF
4996 * and the write will cover all of the existing data.
4997 */
4998 if (CIFS_CACHE_READ(CIFS_I(mapping->host))) {
4999 i_size = i_size_read(mapping->host);
5000 if (page_start >= i_size ||
5001 (offset == 0 && (pos + len) >= i_size)) {
5002 zero_user_segments(page, 0, offset,
5003 offset + len,
5004 PAGE_SIZE);
5005 /*
5006 * PageChecked means that the parts of the page
5007 * to which we're not writing are considered up
5008 * to date. Once the data is copied to the
5009 * page, it can be set uptodate.
5010 */
5011 SetPageChecked(page);
5012 goto out;
5013 }
5014 }
5015
5016 if ((file->f_flags & O_ACCMODE) != O_WRONLY && !oncethru) {
5017 /*
5018 * might as well read a page, it is fast enough. If we get
5019 * an error, we don't need to return it. cifs_write_end will
5020 * do a sync write instead since PG_uptodate isn't set.
5021 */
5022 cifs_readpage_worker(file, page, &page_start);
5023 put_page(page);
5024 oncethru = 1;
5025 goto start;
5026 } else {
5027 /* we could try using another file handle if there is one -
5028 but how would we lock it to prevent close of that handle
5029 racing with this read? In any case
5030 this will be written out by write_end so is fine */
5031 }
5032 out:
5033 *pagep = page;
5034 return rc;
5035 }
5036
cifs_release_folio(struct folio * folio,gfp_t gfp)5037 static bool cifs_release_folio(struct folio *folio, gfp_t gfp)
5038 {
5039 if (folio_test_private(folio))
5040 return 0;
5041 if (folio_test_fscache(folio)) {
5042 if (current_is_kswapd() || !(gfp & __GFP_FS))
5043 return false;
5044 folio_wait_fscache(folio);
5045 }
5046 fscache_note_page_release(cifs_inode_cookie(folio->mapping->host));
5047 return true;
5048 }
5049
cifs_invalidate_folio(struct folio * folio,size_t offset,size_t length)5050 static void cifs_invalidate_folio(struct folio *folio, size_t offset,
5051 size_t length)
5052 {
5053 folio_wait_fscache(folio);
5054 }
5055
cifs_launder_folio(struct folio * folio)5056 static int cifs_launder_folio(struct folio *folio)
5057 {
5058 int rc = 0;
5059 loff_t range_start = folio_pos(folio);
5060 loff_t range_end = range_start + folio_size(folio);
5061 struct writeback_control wbc = {
5062 .sync_mode = WB_SYNC_ALL,
5063 .nr_to_write = 0,
5064 .range_start = range_start,
5065 .range_end = range_end,
5066 };
5067
5068 cifs_dbg(FYI, "Launder page: %lu\n", folio->index);
5069
5070 if (folio_clear_dirty_for_io(folio))
5071 rc = cifs_writepage_locked(&folio->page, &wbc);
5072
5073 folio_wait_fscache(folio);
5074 return rc;
5075 }
5076
cifs_oplock_break(struct work_struct * work)5077 void cifs_oplock_break(struct work_struct *work)
5078 {
5079 struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
5080 oplock_break);
5081 struct inode *inode = d_inode(cfile->dentry);
5082 struct cifsInodeInfo *cinode = CIFS_I(inode);
5083 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
5084 struct TCP_Server_Info *server = tcon->ses->server;
5085 int rc = 0;
5086 bool purge_cache = false;
5087
5088 wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
5089 TASK_UNINTERRUPTIBLE);
5090
5091 server->ops->downgrade_oplock(server, cinode, cfile->oplock_level,
5092 cfile->oplock_epoch, &purge_cache);
5093
5094 if (!CIFS_CACHE_WRITE(cinode) && CIFS_CACHE_READ(cinode) &&
5095 cifs_has_mand_locks(cinode)) {
5096 cifs_dbg(FYI, "Reset oplock to None for inode=%p due to mand locks\n",
5097 inode);
5098 cinode->oplock = 0;
5099 }
5100
5101 if (inode && S_ISREG(inode->i_mode)) {
5102 if (CIFS_CACHE_READ(cinode))
5103 break_lease(inode, O_RDONLY);
5104 else
5105 break_lease(inode, O_WRONLY);
5106 rc = filemap_fdatawrite(inode->i_mapping);
5107 if (!CIFS_CACHE_READ(cinode) || purge_cache) {
5108 rc = filemap_fdatawait(inode->i_mapping);
5109 mapping_set_error(inode->i_mapping, rc);
5110 cifs_zap_mapping(inode);
5111 }
5112 cifs_dbg(FYI, "Oplock flush inode %p rc %d\n", inode, rc);
5113 if (CIFS_CACHE_WRITE(cinode))
5114 goto oplock_break_ack;
5115 }
5116
5117 rc = cifs_push_locks(cfile);
5118 if (rc)
5119 cifs_dbg(VFS, "Push locks rc = %d\n", rc);
5120
5121 oplock_break_ack:
5122 /*
5123 * releasing stale oplock after recent reconnect of smb session using
5124 * a now incorrect file handle is not a data integrity issue but do
5125 * not bother sending an oplock release if session to server still is
5126 * disconnected since oplock already released by the server
5127 */
5128 if (!cfile->oplock_break_cancelled) {
5129 rc = tcon->ses->server->ops->oplock_response(tcon, &cfile->fid,
5130 cinode);
5131 cifs_dbg(FYI, "Oplock release rc = %d\n", rc);
5132 }
5133
5134 _cifsFileInfo_put(cfile, false /* do not wait for ourself */, false);
5135 cifs_done_oplock_break(cinode);
5136 }
5137
5138 /*
5139 * The presence of cifs_direct_io() in the address space ops vector
5140 * allowes open() O_DIRECT flags which would have failed otherwise.
5141 *
5142 * In the non-cached mode (mount with cache=none), we shunt off direct read and write requests
5143 * so this method should never be called.
5144 *
5145 * Direct IO is not yet supported in the cached mode.
5146 */
5147 static ssize_t
cifs_direct_io(struct kiocb * iocb,struct iov_iter * iter)5148 cifs_direct_io(struct kiocb *iocb, struct iov_iter *iter)
5149 {
5150 /*
5151 * FIXME
5152 * Eventually need to support direct IO for non forcedirectio mounts
5153 */
5154 return -EINVAL;
5155 }
5156
cifs_swap_activate(struct swap_info_struct * sis,struct file * swap_file,sector_t * span)5157 static int cifs_swap_activate(struct swap_info_struct *sis,
5158 struct file *swap_file, sector_t *span)
5159 {
5160 struct cifsFileInfo *cfile = swap_file->private_data;
5161 struct inode *inode = swap_file->f_mapping->host;
5162 unsigned long blocks;
5163 long long isize;
5164
5165 cifs_dbg(FYI, "swap activate\n");
5166
5167 if (!swap_file->f_mapping->a_ops->swap_rw)
5168 /* Cannot support swap */
5169 return -EINVAL;
5170
5171 spin_lock(&inode->i_lock);
5172 blocks = inode->i_blocks;
5173 isize = inode->i_size;
5174 spin_unlock(&inode->i_lock);
5175 if (blocks*512 < isize) {
5176 pr_warn("swap activate: swapfile has holes\n");
5177 return -EINVAL;
5178 }
5179 *span = sis->pages;
5180
5181 pr_warn_once("Swap support over SMB3 is experimental\n");
5182
5183 /*
5184 * TODO: consider adding ACL (or documenting how) to prevent other
5185 * users (on this or other systems) from reading it
5186 */
5187
5188
5189 /* TODO: add sk_set_memalloc(inet) or similar */
5190
5191 if (cfile)
5192 cfile->swapfile = true;
5193 /*
5194 * TODO: Since file already open, we can't open with DENY_ALL here
5195 * but we could add call to grab a byte range lock to prevent others
5196 * from reading or writing the file
5197 */
5198
5199 sis->flags |= SWP_FS_OPS;
5200 return add_swap_extent(sis, 0, sis->max, 0);
5201 }
5202
cifs_swap_deactivate(struct file * file)5203 static void cifs_swap_deactivate(struct file *file)
5204 {
5205 struct cifsFileInfo *cfile = file->private_data;
5206
5207 cifs_dbg(FYI, "swap deactivate\n");
5208
5209 /* TODO: undo sk_set_memalloc(inet) will eventually be needed */
5210
5211 if (cfile)
5212 cfile->swapfile = false;
5213
5214 /* do we need to unpin (or unlock) the file */
5215 }
5216
5217 /*
5218 * Mark a page as having been made dirty and thus needing writeback. We also
5219 * need to pin the cache object to write back to.
5220 */
5221 #ifdef CONFIG_CIFS_FSCACHE
cifs_dirty_folio(struct address_space * mapping,struct folio * folio)5222 static bool cifs_dirty_folio(struct address_space *mapping, struct folio *folio)
5223 {
5224 return fscache_dirty_folio(mapping, folio,
5225 cifs_inode_cookie(mapping->host));
5226 }
5227 #else
5228 #define cifs_dirty_folio filemap_dirty_folio
5229 #endif
5230
5231 const struct address_space_operations cifs_addr_ops = {
5232 .read_folio = cifs_read_folio,
5233 .readahead = cifs_readahead,
5234 .writepage = cifs_writepage,
5235 .writepages = cifs_writepages,
5236 .write_begin = cifs_write_begin,
5237 .write_end = cifs_write_end,
5238 .dirty_folio = cifs_dirty_folio,
5239 .release_folio = cifs_release_folio,
5240 .direct_IO = cifs_direct_io,
5241 .invalidate_folio = cifs_invalidate_folio,
5242 .launder_folio = cifs_launder_folio,
5243 /*
5244 * TODO: investigate and if useful we could add an cifs_migratePage
5245 * helper (under an CONFIG_MIGRATION) in the future, and also
5246 * investigate and add an is_dirty_writeback helper if needed
5247 */
5248 .swap_activate = cifs_swap_activate,
5249 .swap_deactivate = cifs_swap_deactivate,
5250 };
5251
5252 /*
5253 * cifs_readahead requires the server to support a buffer large enough to
5254 * contain the header plus one complete page of data. Otherwise, we need
5255 * to leave cifs_readahead out of the address space operations.
5256 */
5257 const struct address_space_operations cifs_addr_ops_smallbuf = {
5258 .read_folio = cifs_read_folio,
5259 .writepage = cifs_writepage,
5260 .writepages = cifs_writepages,
5261 .write_begin = cifs_write_begin,
5262 .write_end = cifs_write_end,
5263 .dirty_folio = cifs_dirty_folio,
5264 .release_folio = cifs_release_folio,
5265 .invalidate_folio = cifs_invalidate_folio,
5266 .launder_folio = cifs_launder_folio,
5267 };
5268