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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 */
43void
44cifs_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
80static 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
99static 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
134static 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
149int 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
206posix_open_ret:
207 kfree(presp_data);
208 return rc;
209}
210#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
211
212static 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
293static bool
294cifs_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
310void
311cifs_down_write(struct rw_semaphore *sem)
312{
313 while (!down_write_trylock(sem))
314 msleep(10);
315}
316
317static void cifsFileInfo_put_work(struct work_struct *work);
318
319struct 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
410struct cifsFileInfo *
411cifsFileInfo_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
419static 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
447static 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 */
462void 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 */
483void _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
560int 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
704use_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
713out:
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
722static 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 */
729static int
730cifs_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
759static int
760cifs_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
883reopen_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
923reopen_error_exit:
924 free_dentry_path(page);
925 free_xid(xid);
926 return rc;
927}
928
929void 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
941int 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
992void
993cifs_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
1024int 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
1075static struct cifsLockInfo *
1076cifs_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
1092void
1093cifs_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 */
1107static bool
1108cifs_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
1143bool
1144cifs_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 */
1170static int
1171cifs_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
1202static void
1203cifs_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 */
1217static int
1218cifs_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
1226try_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 */
1267static int
1268cifs_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 */
1296static int
1297cifs_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
1316int
1317cifs_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
1393static __u32
1394hash_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
1400struct 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
1410static int
1411cifs_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 = locks_inode_context(inode);
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
1487out:
1488 free_xid(xid);
1489 return rc;
1490err_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
1499static int
1500cifs_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
1530static void
1531cifs_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
1577static int
1578cifs_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
1648void
1649cifs_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
1656void
1657cifs_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
1668int
1669cifs_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
1782static int
1783cifs_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
1859out:
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
1877int 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
1926int 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 */
1985void
1986cifs_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
1995static ssize_t
1996cifs_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
2079struct 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 */
2114int
2115cifs_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);
2146refind_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
2204struct cifsFileInfo *
2205find_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
2217int
2218cifs_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
2250int
2251cifs_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
2283void
2284cifs_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 */
2306static void
2307cifs_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
2401void
2402cifs_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
2434struct cifs_writedata *
2435cifs_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
2449struct cifs_writedata *
2450cifs_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
2466static 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
2524static struct cifs_writedata *
2525wdata_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
2541static unsigned int
2542wdata_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
2620static int
2621wdata_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
2649static int
2650cifs_writepage_locked(struct page *page, struct writeback_control *wbc);
2651
2652static int cifs_write_one_page(struct page *page, struct writeback_control *wbc,
2653 void *data)
2654{
2655 struct address_space *mapping = data;
2656 int ret;
2657
2658 ret = cifs_writepage_locked(page, wbc);
2659 unlock_page(page);
2660 mapping_set_error(mapping, ret);
2661 return ret;
2662}
2663
2664static int cifs_writepages(struct address_space *mapping,
2665 struct writeback_control *wbc)
2666{
2667 struct inode *inode = mapping->host;
2668 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2669 struct TCP_Server_Info *server;
2670 bool done = false, scanned = false, range_whole = false;
2671 pgoff_t end, index;
2672 struct cifs_writedata *wdata;
2673 struct cifsFileInfo *cfile = NULL;
2674 int rc = 0;
2675 int saved_rc = 0;
2676 unsigned int xid;
2677
2678 /*
2679 * If wsize is smaller than the page cache size, default to writing
2680 * one page at a time.
2681 */
2682 if (cifs_sb->ctx->wsize < PAGE_SIZE)
2683 return write_cache_pages(mapping, wbc, cifs_write_one_page,
2684 mapping);
2685
2686 xid = get_xid();
2687 if (wbc->range_cyclic) {
2688 index = mapping->writeback_index; /* Start from prev offset */
2689 end = -1;
2690 } else {
2691 index = wbc->range_start >> PAGE_SHIFT;
2692 end = wbc->range_end >> PAGE_SHIFT;
2693 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
2694 range_whole = true;
2695 scanned = true;
2696 }
2697 server = cifs_pick_channel(cifs_sb_master_tcon(cifs_sb)->ses);
2698
2699retry:
2700 while (!done && index <= end) {
2701 unsigned int i, nr_pages, found_pages, wsize;
2702 pgoff_t next = 0, tofind, saved_index = index;
2703 struct cifs_credits credits_on_stack;
2704 struct cifs_credits *credits = &credits_on_stack;
2705 int get_file_rc = 0;
2706
2707 if (cfile)
2708 cifsFileInfo_put(cfile);
2709
2710 rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY, &cfile);
2711
2712 /* in case of an error store it to return later */
2713 if (rc)
2714 get_file_rc = rc;
2715
2716 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
2717 &wsize, credits);
2718 if (rc != 0) {
2719 done = true;
2720 break;
2721 }
2722
2723 tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1;
2724
2725 wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
2726 &found_pages);
2727 if (!wdata) {
2728 rc = -ENOMEM;
2729 done = true;
2730 add_credits_and_wake_if(server, credits, 0);
2731 break;
2732 }
2733
2734 if (found_pages == 0) {
2735 kref_put(&wdata->refcount, cifs_writedata_release);
2736 add_credits_and_wake_if(server, credits, 0);
2737 break;
2738 }
2739
2740 nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
2741 end, &index, &next, &done);
2742
2743 /* nothing to write? */
2744 if (nr_pages == 0) {
2745 kref_put(&wdata->refcount, cifs_writedata_release);
2746 add_credits_and_wake_if(server, credits, 0);
2747 continue;
2748 }
2749
2750 wdata->credits = credits_on_stack;
2751 wdata->cfile = cfile;
2752 wdata->server = server;
2753 cfile = NULL;
2754
2755 if (!wdata->cfile) {
2756 cifs_dbg(VFS, "No writable handle in writepages rc=%d\n",
2757 get_file_rc);
2758 if (is_retryable_error(get_file_rc))
2759 rc = get_file_rc;
2760 else
2761 rc = -EBADF;
2762 } else
2763 rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
2764
2765 for (i = 0; i < nr_pages; ++i)
2766 unlock_page(wdata->pages[i]);
2767
2768 /* send failure -- clean up the mess */
2769 if (rc != 0) {
2770 add_credits_and_wake_if(server, &wdata->credits, 0);
2771 for (i = 0; i < nr_pages; ++i) {
2772 if (is_retryable_error(rc))
2773 redirty_page_for_writepage(wbc,
2774 wdata->pages[i]);
2775 else
2776 SetPageError(wdata->pages[i]);
2777 end_page_writeback(wdata->pages[i]);
2778 put_page(wdata->pages[i]);
2779 }
2780 if (!is_retryable_error(rc))
2781 mapping_set_error(mapping, rc);
2782 }
2783 kref_put(&wdata->refcount, cifs_writedata_release);
2784
2785 if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) {
2786 index = saved_index;
2787 continue;
2788 }
2789
2790 /* Return immediately if we received a signal during writing */
2791 if (is_interrupt_error(rc)) {
2792 done = true;
2793 break;
2794 }
2795
2796 if (rc != 0 && saved_rc == 0)
2797 saved_rc = rc;
2798
2799 wbc->nr_to_write -= nr_pages;
2800 if (wbc->nr_to_write <= 0)
2801 done = true;
2802
2803 index = next;
2804 }
2805
2806 if (!scanned && !done) {
2807 /*
2808 * We hit the last page and there is more work to be done: wrap
2809 * back to the start of the file
2810 */
2811 scanned = true;
2812 index = 0;
2813 goto retry;
2814 }
2815
2816 if (saved_rc != 0)
2817 rc = saved_rc;
2818
2819 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
2820 mapping->writeback_index = index;
2821
2822 if (cfile)
2823 cifsFileInfo_put(cfile);
2824 free_xid(xid);
2825 /* Indication to update ctime and mtime as close is deferred */
2826 set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
2827 return rc;
2828}
2829
2830static int
2831cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
2832{
2833 int rc;
2834 unsigned int xid;
2835
2836 xid = get_xid();
2837/* BB add check for wbc flags */
2838 get_page(page);
2839 if (!PageUptodate(page))
2840 cifs_dbg(FYI, "ppw - page not up to date\n");
2841
2842 /*
2843 * Set the "writeback" flag, and clear "dirty" in the radix tree.
2844 *
2845 * A writepage() implementation always needs to do either this,
2846 * or re-dirty the page with "redirty_page_for_writepage()" in
2847 * the case of a failure.
2848 *
2849 * Just unlocking the page will cause the radix tree tag-bits
2850 * to fail to update with the state of the page correctly.
2851 */
2852 set_page_writeback(page);
2853retry_write:
2854 rc = cifs_partialpagewrite(page, 0, PAGE_SIZE);
2855 if (is_retryable_error(rc)) {
2856 if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN)
2857 goto retry_write;
2858 redirty_page_for_writepage(wbc, page);
2859 } else if (rc != 0) {
2860 SetPageError(page);
2861 mapping_set_error(page->mapping, rc);
2862 } else {
2863 SetPageUptodate(page);
2864 }
2865 end_page_writeback(page);
2866 put_page(page);
2867 free_xid(xid);
2868 return rc;
2869}
2870
2871static int cifs_write_end(struct file *file, struct address_space *mapping,
2872 loff_t pos, unsigned len, unsigned copied,
2873 struct page *page, void *fsdata)
2874{
2875 int rc;
2876 struct inode *inode = mapping->host;
2877 struct cifsFileInfo *cfile = file->private_data;
2878 struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
2879 __u32 pid;
2880
2881 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
2882 pid = cfile->pid;
2883 else
2884 pid = current->tgid;
2885
2886 cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
2887 page, pos, copied);
2888
2889 if (PageChecked(page)) {
2890 if (copied == len)
2891 SetPageUptodate(page);
2892 ClearPageChecked(page);
2893 } else if (!PageUptodate(page) && copied == PAGE_SIZE)
2894 SetPageUptodate(page);
2895
2896 if (!PageUptodate(page)) {
2897 char *page_data;
2898 unsigned offset = pos & (PAGE_SIZE - 1);
2899 unsigned int xid;
2900
2901 xid = get_xid();
2902 /* this is probably better than directly calling
2903 partialpage_write since in this function the file handle is
2904 known which we might as well leverage */
2905 /* BB check if anything else missing out of ppw
2906 such as updating last write time */
2907 page_data = kmap(page);
2908 rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
2909 /* if (rc < 0) should we set writebehind rc? */
2910 kunmap(page);
2911
2912 free_xid(xid);
2913 } else {
2914 rc = copied;
2915 pos += copied;
2916 set_page_dirty(page);
2917 }
2918
2919 if (rc > 0) {
2920 spin_lock(&inode->i_lock);
2921 if (pos > inode->i_size) {
2922 i_size_write(inode, pos);
2923 inode->i_blocks = (512 - 1 + pos) >> 9;
2924 }
2925 spin_unlock(&inode->i_lock);
2926 }
2927
2928 unlock_page(page);
2929 put_page(page);
2930 /* Indication to update ctime and mtime as close is deferred */
2931 set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
2932
2933 return rc;
2934}
2935
2936int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
2937 int datasync)
2938{
2939 unsigned int xid;
2940 int rc = 0;
2941 struct cifs_tcon *tcon;
2942 struct TCP_Server_Info *server;
2943 struct cifsFileInfo *smbfile = file->private_data;
2944 struct inode *inode = file_inode(file);
2945 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
2946
2947 rc = file_write_and_wait_range(file, start, end);
2948 if (rc) {
2949 trace_cifs_fsync_err(inode->i_ino, rc);
2950 return rc;
2951 }
2952
2953 xid = get_xid();
2954
2955 cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
2956 file, datasync);
2957
2958 if (!CIFS_CACHE_READ(CIFS_I(inode))) {
2959 rc = cifs_zap_mapping(inode);
2960 if (rc) {
2961 cifs_dbg(FYI, "rc: %d during invalidate phase\n", rc);
2962 rc = 0; /* don't care about it in fsync */
2963 }
2964 }
2965
2966 tcon = tlink_tcon(smbfile->tlink);
2967 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
2968 server = tcon->ses->server;
2969 if (server->ops->flush == NULL) {
2970 rc = -ENOSYS;
2971 goto strict_fsync_exit;
2972 }
2973
2974 if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
2975 smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
2976 if (smbfile) {
2977 rc = server->ops->flush(xid, tcon, &smbfile->fid);
2978 cifsFileInfo_put(smbfile);
2979 } else
2980 cifs_dbg(FYI, "ignore fsync for file not open for write\n");
2981 } else
2982 rc = server->ops->flush(xid, tcon, &smbfile->fid);
2983 }
2984
2985strict_fsync_exit:
2986 free_xid(xid);
2987 return rc;
2988}
2989
2990int cifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2991{
2992 unsigned int xid;
2993 int rc = 0;
2994 struct cifs_tcon *tcon;
2995 struct TCP_Server_Info *server;
2996 struct cifsFileInfo *smbfile = file->private_data;
2997 struct inode *inode = file_inode(file);
2998 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
2999
3000 rc = file_write_and_wait_range(file, start, end);
3001 if (rc) {
3002 trace_cifs_fsync_err(file_inode(file)->i_ino, rc);
3003 return rc;
3004 }
3005
3006 xid = get_xid();
3007
3008 cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
3009 file, datasync);
3010
3011 tcon = tlink_tcon(smbfile->tlink);
3012 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
3013 server = tcon->ses->server;
3014 if (server->ops->flush == NULL) {
3015 rc = -ENOSYS;
3016 goto fsync_exit;
3017 }
3018
3019 if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
3020 smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
3021 if (smbfile) {
3022 rc = server->ops->flush(xid, tcon, &smbfile->fid);
3023 cifsFileInfo_put(smbfile);
3024 } else
3025 cifs_dbg(FYI, "ignore fsync for file not open for write\n");
3026 } else
3027 rc = server->ops->flush(xid, tcon, &smbfile->fid);
3028 }
3029
3030fsync_exit:
3031 free_xid(xid);
3032 return rc;
3033}
3034
3035/*
3036 * As file closes, flush all cached write data for this inode checking
3037 * for write behind errors.
3038 */
3039int cifs_flush(struct file *file, fl_owner_t id)
3040{
3041 struct inode *inode = file_inode(file);
3042 int rc = 0;
3043
3044 if (file->f_mode & FMODE_WRITE)
3045 rc = filemap_write_and_wait(inode->i_mapping);
3046
3047 cifs_dbg(FYI, "Flush inode %p file %p rc %d\n", inode, file, rc);
3048 if (rc) {
3049 /* get more nuanced writeback errors */
3050 rc = filemap_check_wb_err(file->f_mapping, 0);
3051 trace_cifs_flush_err(inode->i_ino, rc);
3052 }
3053 return rc;
3054}
3055
3056static int
3057cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
3058{
3059 int rc = 0;
3060 unsigned long i;
3061
3062 for (i = 0; i < num_pages; i++) {
3063 pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
3064 if (!pages[i]) {
3065 /*
3066 * save number of pages we have already allocated and
3067 * return with ENOMEM error
3068 */
3069 num_pages = i;
3070 rc = -ENOMEM;
3071 break;
3072 }
3073 }
3074
3075 if (rc) {
3076 for (i = 0; i < num_pages; i++)
3077 put_page(pages[i]);
3078 }
3079 return rc;
3080}
3081
3082static inline
3083size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
3084{
3085 size_t num_pages;
3086 size_t clen;
3087
3088 clen = min_t(const size_t, len, wsize);
3089 num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
3090
3091 if (cur_len)
3092 *cur_len = clen;
3093
3094 return num_pages;
3095}
3096
3097static void
3098cifs_uncached_writedata_release(struct kref *refcount)
3099{
3100 int i;
3101 struct cifs_writedata *wdata = container_of(refcount,
3102 struct cifs_writedata, refcount);
3103
3104 kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
3105 for (i = 0; i < wdata->nr_pages; i++)
3106 put_page(wdata->pages[i]);
3107 cifs_writedata_release(refcount);
3108}
3109
3110static void collect_uncached_write_data(struct cifs_aio_ctx *ctx);
3111
3112static void
3113cifs_uncached_writev_complete(struct work_struct *work)
3114{
3115 struct cifs_writedata *wdata = container_of(work,
3116 struct cifs_writedata, work);
3117 struct inode *inode = d_inode(wdata->cfile->dentry);
3118 struct cifsInodeInfo *cifsi = CIFS_I(inode);
3119
3120 spin_lock(&inode->i_lock);
3121 cifs_update_eof(cifsi, wdata->offset, wdata->bytes);
3122 if (cifsi->server_eof > inode->i_size)
3123 i_size_write(inode, cifsi->server_eof);
3124 spin_unlock(&inode->i_lock);
3125
3126 complete(&wdata->done);
3127 collect_uncached_write_data(wdata->ctx);
3128 /* the below call can possibly free the last ref to aio ctx */
3129 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
3130}
3131
3132static int
3133wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
3134 size_t *len, unsigned long *num_pages)
3135{
3136 size_t save_len, copied, bytes, cur_len = *len;
3137 unsigned long i, nr_pages = *num_pages;
3138
3139 save_len = cur_len;
3140 for (i = 0; i < nr_pages; i++) {
3141 bytes = min_t(const size_t, cur_len, PAGE_SIZE);
3142 copied = copy_page_from_iter(wdata->pages[i], 0, bytes, from);
3143 cur_len -= copied;
3144 /*
3145 * If we didn't copy as much as we expected, then that
3146 * may mean we trod into an unmapped area. Stop copying
3147 * at that point. On the next pass through the big
3148 * loop, we'll likely end up getting a zero-length
3149 * write and bailing out of it.
3150 */
3151 if (copied < bytes)
3152 break;
3153 }
3154 cur_len = save_len - cur_len;
3155 *len = cur_len;
3156
3157 /*
3158 * If we have no data to send, then that probably means that
3159 * the copy above failed altogether. That's most likely because
3160 * the address in the iovec was bogus. Return -EFAULT and let
3161 * the caller free anything we allocated and bail out.
3162 */
3163 if (!cur_len)
3164 return -EFAULT;
3165
3166 /*
3167 * i + 1 now represents the number of pages we actually used in
3168 * the copy phase above.
3169 */
3170 *num_pages = i + 1;
3171 return 0;
3172}
3173
3174static int
3175cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,
3176 struct cifs_aio_ctx *ctx)
3177{
3178 unsigned int wsize;
3179 struct cifs_credits credits;
3180 int rc;
3181 struct TCP_Server_Info *server = wdata->server;
3182
3183 do {
3184 if (wdata->cfile->invalidHandle) {
3185 rc = cifs_reopen_file(wdata->cfile, false);
3186 if (rc == -EAGAIN)
3187 continue;
3188 else if (rc)
3189 break;
3190 }
3191
3192
3193 /*
3194 * Wait for credits to resend this wdata.
3195 * Note: we are attempting to resend the whole wdata not in
3196 * segments
3197 */
3198 do {
3199 rc = server->ops->wait_mtu_credits(server, wdata->bytes,
3200 &wsize, &credits);
3201 if (rc)
3202 goto fail;
3203
3204 if (wsize < wdata->bytes) {
3205 add_credits_and_wake_if(server, &credits, 0);
3206 msleep(1000);
3207 }
3208 } while (wsize < wdata->bytes);
3209 wdata->credits = credits;
3210
3211 rc = adjust_credits(server, &wdata->credits, wdata->bytes);
3212
3213 if (!rc) {
3214 if (wdata->cfile->invalidHandle)
3215 rc = -EAGAIN;
3216 else {
3217#ifdef CONFIG_CIFS_SMB_DIRECT
3218 if (wdata->mr) {
3219 wdata->mr->need_invalidate = true;
3220 smbd_deregister_mr(wdata->mr);
3221 wdata->mr = NULL;
3222 }
3223#endif
3224 rc = server->ops->async_writev(wdata,
3225 cifs_uncached_writedata_release);
3226 }
3227 }
3228
3229 /* If the write was successfully sent, we are done */
3230 if (!rc) {
3231 list_add_tail(&wdata->list, wdata_list);
3232 return 0;
3233 }
3234
3235 /* Roll back credits and retry if needed */
3236 add_credits_and_wake_if(server, &wdata->credits, 0);
3237 } while (rc == -EAGAIN);
3238
3239fail:
3240 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
3241 return rc;
3242}
3243
3244static int
3245cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
3246 struct cifsFileInfo *open_file,
3247 struct cifs_sb_info *cifs_sb, struct list_head *wdata_list,
3248 struct cifs_aio_ctx *ctx)
3249{
3250 int rc = 0;
3251 size_t cur_len;
3252 unsigned long nr_pages, num_pages, i;
3253 struct cifs_writedata *wdata;
3254 struct iov_iter saved_from = *from;
3255 loff_t saved_offset = offset;
3256 pid_t pid;
3257 struct TCP_Server_Info *server;
3258 struct page **pagevec;
3259 size_t start;
3260 unsigned int xid;
3261
3262 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
3263 pid = open_file->pid;
3264 else
3265 pid = current->tgid;
3266
3267 server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
3268 xid = get_xid();
3269
3270 do {
3271 unsigned int wsize;
3272 struct cifs_credits credits_on_stack;
3273 struct cifs_credits *credits = &credits_on_stack;
3274
3275 if (open_file->invalidHandle) {
3276 rc = cifs_reopen_file(open_file, false);
3277 if (rc == -EAGAIN)
3278 continue;
3279 else if (rc)
3280 break;
3281 }
3282
3283 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
3284 &wsize, credits);
3285 if (rc)
3286 break;
3287
3288 cur_len = min_t(const size_t, len, wsize);
3289
3290 if (ctx->direct_io) {
3291 ssize_t result;
3292
3293 result = iov_iter_get_pages_alloc2(
3294 from, &pagevec, cur_len, &start);
3295 if (result < 0) {
3296 cifs_dbg(VFS,
3297 "direct_writev couldn't get user pages (rc=%zd) iter type %d iov_offset %zd count %zd\n",
3298 result, iov_iter_type(from),
3299 from->iov_offset, from->count);
3300 dump_stack();
3301
3302 rc = result;
3303 add_credits_and_wake_if(server, credits, 0);
3304 break;
3305 }
3306 cur_len = (size_t)result;
3307
3308 nr_pages =
3309 (cur_len + start + PAGE_SIZE - 1) / PAGE_SIZE;
3310
3311 wdata = cifs_writedata_direct_alloc(pagevec,
3312 cifs_uncached_writev_complete);
3313 if (!wdata) {
3314 rc = -ENOMEM;
3315 for (i = 0; i < nr_pages; i++)
3316 put_page(pagevec[i]);
3317 kvfree(pagevec);
3318 add_credits_and_wake_if(server, credits, 0);
3319 break;
3320 }
3321
3322
3323 wdata->page_offset = start;
3324 wdata->tailsz =
3325 nr_pages > 1 ?
3326 cur_len - (PAGE_SIZE - start) -
3327 (nr_pages - 2) * PAGE_SIZE :
3328 cur_len;
3329 } else {
3330 nr_pages = get_numpages(wsize, len, &cur_len);
3331 wdata = cifs_writedata_alloc(nr_pages,
3332 cifs_uncached_writev_complete);
3333 if (!wdata) {
3334 rc = -ENOMEM;
3335 add_credits_and_wake_if(server, credits, 0);
3336 break;
3337 }
3338
3339 rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
3340 if (rc) {
3341 kvfree(wdata->pages);
3342 kfree(wdata);
3343 add_credits_and_wake_if(server, credits, 0);
3344 break;
3345 }
3346
3347 num_pages = nr_pages;
3348 rc = wdata_fill_from_iovec(
3349 wdata, from, &cur_len, &num_pages);
3350 if (rc) {
3351 for (i = 0; i < nr_pages; i++)
3352 put_page(wdata->pages[i]);
3353 kvfree(wdata->pages);
3354 kfree(wdata);
3355 add_credits_and_wake_if(server, credits, 0);
3356 break;
3357 }
3358
3359 /*
3360 * Bring nr_pages down to the number of pages we
3361 * actually used, and free any pages that we didn't use.
3362 */
3363 for ( ; nr_pages > num_pages; nr_pages--)
3364 put_page(wdata->pages[nr_pages - 1]);
3365
3366 wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
3367 }
3368
3369 wdata->sync_mode = WB_SYNC_ALL;
3370 wdata->nr_pages = nr_pages;
3371 wdata->offset = (__u64)offset;
3372 wdata->cfile = cifsFileInfo_get(open_file);
3373 wdata->server = server;
3374 wdata->pid = pid;
3375 wdata->bytes = cur_len;
3376 wdata->pagesz = PAGE_SIZE;
3377 wdata->credits = credits_on_stack;
3378 wdata->ctx = ctx;
3379 kref_get(&ctx->refcount);
3380
3381 rc = adjust_credits(server, &wdata->credits, wdata->bytes);
3382
3383 if (!rc) {
3384 if (wdata->cfile->invalidHandle)
3385 rc = -EAGAIN;
3386 else
3387 rc = server->ops->async_writev(wdata,
3388 cifs_uncached_writedata_release);
3389 }
3390
3391 if (rc) {
3392 add_credits_and_wake_if(server, &wdata->credits, 0);
3393 kref_put(&wdata->refcount,
3394 cifs_uncached_writedata_release);
3395 if (rc == -EAGAIN) {
3396 *from = saved_from;
3397 iov_iter_advance(from, offset - saved_offset);
3398 continue;
3399 }
3400 break;
3401 }
3402
3403 list_add_tail(&wdata->list, wdata_list);
3404 offset += cur_len;
3405 len -= cur_len;
3406 } while (len > 0);
3407
3408 free_xid(xid);
3409 return rc;
3410}
3411
3412static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
3413{
3414 struct cifs_writedata *wdata, *tmp;
3415 struct cifs_tcon *tcon;
3416 struct cifs_sb_info *cifs_sb;
3417 struct dentry *dentry = ctx->cfile->dentry;
3418 ssize_t rc;
3419
3420 tcon = tlink_tcon(ctx->cfile->tlink);
3421 cifs_sb = CIFS_SB(dentry->d_sb);
3422
3423 mutex_lock(&ctx->aio_mutex);
3424
3425 if (list_empty(&ctx->list)) {
3426 mutex_unlock(&ctx->aio_mutex);
3427 return;
3428 }
3429
3430 rc = ctx->rc;
3431 /*
3432 * Wait for and collect replies for any successful sends in order of
3433 * increasing offset. Once an error is hit, then return without waiting
3434 * for any more replies.
3435 */
3436restart_loop:
3437 list_for_each_entry_safe(wdata, tmp, &ctx->list, list) {
3438 if (!rc) {
3439 if (!try_wait_for_completion(&wdata->done)) {
3440 mutex_unlock(&ctx->aio_mutex);
3441 return;
3442 }
3443
3444 if (wdata->result)
3445 rc = wdata->result;
3446 else
3447 ctx->total_len += wdata->bytes;
3448
3449 /* resend call if it's a retryable error */
3450 if (rc == -EAGAIN) {
3451 struct list_head tmp_list;
3452 struct iov_iter tmp_from = ctx->iter;
3453
3454 INIT_LIST_HEAD(&tmp_list);
3455 list_del_init(&wdata->list);
3456
3457 if (ctx->direct_io)
3458 rc = cifs_resend_wdata(
3459 wdata, &tmp_list, ctx);
3460 else {
3461 iov_iter_advance(&tmp_from,
3462 wdata->offset - ctx->pos);
3463
3464 rc = cifs_write_from_iter(wdata->offset,
3465 wdata->bytes, &tmp_from,
3466 ctx->cfile, cifs_sb, &tmp_list,
3467 ctx);
3468
3469 kref_put(&wdata->refcount,
3470 cifs_uncached_writedata_release);
3471 }
3472
3473 list_splice(&tmp_list, &ctx->list);
3474 goto restart_loop;
3475 }
3476 }
3477 list_del_init(&wdata->list);
3478 kref_put(&wdata->refcount, cifs_uncached_writedata_release);
3479 }
3480
3481 cifs_stats_bytes_written(tcon, ctx->total_len);
3482 set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(dentry->d_inode)->flags);
3483
3484 ctx->rc = (rc == 0) ? ctx->total_len : rc;
3485
3486 mutex_unlock(&ctx->aio_mutex);
3487
3488 if (ctx->iocb && ctx->iocb->ki_complete)
3489 ctx->iocb->ki_complete(ctx->iocb, ctx->rc);
3490 else
3491 complete(&ctx->done);
3492}
3493
3494static ssize_t __cifs_writev(
3495 struct kiocb *iocb, struct iov_iter *from, bool direct)
3496{
3497 struct file *file = iocb->ki_filp;
3498 ssize_t total_written = 0;
3499 struct cifsFileInfo *cfile;
3500 struct cifs_tcon *tcon;
3501 struct cifs_sb_info *cifs_sb;
3502 struct cifs_aio_ctx *ctx;
3503 struct iov_iter saved_from = *from;
3504 size_t len = iov_iter_count(from);
3505 int rc;
3506
3507 /*
3508 * iov_iter_get_pages_alloc doesn't work with ITER_KVEC.
3509 * In this case, fall back to non-direct write function.
3510 * this could be improved by getting pages directly in ITER_KVEC
3511 */
3512 if (direct && iov_iter_is_kvec(from)) {
3513 cifs_dbg(FYI, "use non-direct cifs_writev for kvec I/O\n");
3514 direct = false;
3515 }
3516
3517 rc = generic_write_checks(iocb, from);
3518 if (rc <= 0)
3519 return rc;
3520
3521 cifs_sb = CIFS_FILE_SB(file);
3522 cfile = file->private_data;
3523 tcon = tlink_tcon(cfile->tlink);
3524
3525 if (!tcon->ses->server->ops->async_writev)
3526 return -ENOSYS;
3527
3528 ctx = cifs_aio_ctx_alloc();
3529 if (!ctx)
3530 return -ENOMEM;
3531
3532 ctx->cfile = cifsFileInfo_get(cfile);
3533
3534 if (!is_sync_kiocb(iocb))
3535 ctx->iocb = iocb;
3536
3537 ctx->pos = iocb->ki_pos;
3538
3539 if (direct) {
3540 ctx->direct_io = true;
3541 ctx->iter = *from;
3542 ctx->len = len;
3543 } else {
3544 rc = setup_aio_ctx_iter(ctx, from, ITER_SOURCE);
3545 if (rc) {
3546 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3547 return rc;
3548 }
3549 }
3550
3551 /* grab a lock here due to read response handlers can access ctx */
3552 mutex_lock(&ctx->aio_mutex);
3553
3554 rc = cifs_write_from_iter(iocb->ki_pos, ctx->len, &saved_from,
3555 cfile, cifs_sb, &ctx->list, ctx);
3556
3557 /*
3558 * If at least one write was successfully sent, then discard any rc
3559 * value from the later writes. If the other write succeeds, then
3560 * we'll end up returning whatever was written. If it fails, then
3561 * we'll get a new rc value from that.
3562 */
3563 if (!list_empty(&ctx->list))
3564 rc = 0;
3565
3566 mutex_unlock(&ctx->aio_mutex);
3567
3568 if (rc) {
3569 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3570 return rc;
3571 }
3572
3573 if (!is_sync_kiocb(iocb)) {
3574 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3575 return -EIOCBQUEUED;
3576 }
3577
3578 rc = wait_for_completion_killable(&ctx->done);
3579 if (rc) {
3580 mutex_lock(&ctx->aio_mutex);
3581 ctx->rc = rc = -EINTR;
3582 total_written = ctx->total_len;
3583 mutex_unlock(&ctx->aio_mutex);
3584 } else {
3585 rc = ctx->rc;
3586 total_written = ctx->total_len;
3587 }
3588
3589 kref_put(&ctx->refcount, cifs_aio_ctx_release);
3590
3591 if (unlikely(!total_written))
3592 return rc;
3593
3594 iocb->ki_pos += total_written;
3595 return total_written;
3596}
3597
3598ssize_t cifs_direct_writev(struct kiocb *iocb, struct iov_iter *from)
3599{
3600 struct file *file = iocb->ki_filp;
3601
3602 cifs_revalidate_mapping(file->f_inode);
3603 return __cifs_writev(iocb, from, true);
3604}
3605
3606ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
3607{
3608 return __cifs_writev(iocb, from, false);
3609}
3610
3611static ssize_t
3612cifs_writev(struct kiocb *iocb, struct iov_iter *from)
3613{
3614 struct file *file = iocb->ki_filp;
3615 struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
3616 struct inode *inode = file->f_mapping->host;
3617 struct cifsInodeInfo *cinode = CIFS_I(inode);
3618 struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
3619 ssize_t rc;
3620
3621 inode_lock(inode);
3622 /*
3623 * We need to hold the sem to be sure nobody modifies lock list
3624 * with a brlock that prevents writing.
3625 */
3626 down_read(&cinode->lock_sem);
3627
3628 rc = generic_write_checks(iocb, from);
3629 if (rc <= 0)
3630 goto out;
3631
3632 if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(from),
3633 server->vals->exclusive_lock_type, 0,
3634 NULL, CIFS_WRITE_OP))
3635 rc = __generic_file_write_iter(iocb, from);
3636 else
3637 rc = -EACCES;
3638out:
3639 up_read(&cinode->lock_sem);
3640 inode_unlock(inode);
3641
3642 if (rc > 0)
3643 rc = generic_write_sync(iocb, rc);
3644 return rc;
3645}
3646
3647ssize_t
3648cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
3649{
3650 struct inode *inode = file_inode(iocb->ki_filp);
3651 struct cifsInodeInfo *cinode = CIFS_I(inode);
3652 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
3653 struct cifsFileInfo *cfile = (struct cifsFileInfo *)
3654 iocb->ki_filp->private_data;
3655 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
3656 ssize_t written;
3657
3658 written = cifs_get_writer(cinode);
3659 if (written)
3660 return written;
3661
3662 if (CIFS_CACHE_WRITE(cinode)) {
3663 if (cap_unix(tcon->ses) &&
3664 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
3665 && ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
3666 written = generic_file_write_iter(iocb, from);
3667 goto out;
3668 }
3669 written = cifs_writev(iocb, from);
3670 goto out;
3671 }
3672 /*
3673 * For non-oplocked files in strict cache mode we need to write the data
3674 * to the server exactly from the pos to pos+len-1 rather than flush all
3675 * affected pages because it may cause a error with mandatory locks on
3676 * these pages but not on the region from pos to ppos+len-1.
3677 */
3678 written = cifs_user_writev(iocb, from);
3679 if (CIFS_CACHE_READ(cinode)) {
3680 /*
3681 * We have read level caching and we have just sent a write
3682 * request to the server thus making data in the cache stale.
3683 * Zap the cache and set oplock/lease level to NONE to avoid
3684 * reading stale data from the cache. All subsequent read
3685 * operations will read new data from the server.
3686 */
3687 cifs_zap_mapping(inode);
3688 cifs_dbg(FYI, "Set Oplock/Lease to NONE for inode=%p after write\n",
3689 inode);
3690 cinode->oplock = 0;
3691 }
3692out:
3693 cifs_put_writer(cinode);
3694 return written;
3695}
3696
3697static struct cifs_readdata *
3698cifs_readdata_direct_alloc(struct page **pages, work_func_t complete)
3699{
3700 struct cifs_readdata *rdata;
3701
3702 rdata = kzalloc(sizeof(*rdata), GFP_KERNEL);
3703 if (rdata != NULL) {
3704 rdata->pages = pages;
3705 kref_init(&rdata->refcount);
3706 INIT_LIST_HEAD(&rdata->list);
3707 init_completion(&rdata->done);
3708 INIT_WORK(&rdata->work, complete);
3709 }
3710
3711 return rdata;
3712}
3713
3714static struct cifs_readdata *
3715cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete)
3716{
3717 struct page **pages =
3718 kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
3719 struct cifs_readdata *ret = NULL;
3720
3721 if (pages) {
3722 ret = cifs_readdata_direct_alloc(pages, complete);
3723 if (!ret)
3724 kfree(pages);
3725 }
3726
3727 return ret;
3728}
3729
3730void
3731cifs_readdata_release(struct kref *refcount)
3732{
3733 struct cifs_readdata *rdata = container_of(refcount,
3734 struct cifs_readdata, refcount);
3735#ifdef CONFIG_CIFS_SMB_DIRECT
3736 if (rdata->mr) {
3737 smbd_deregister_mr(rdata->mr);
3738 rdata->mr = NULL;
3739 }
3740#endif
3741 if (rdata->cfile)
3742 cifsFileInfo_put(rdata->cfile);
3743
3744 kvfree(rdata->pages);
3745 kfree(rdata);
3746}
3747
3748static int
3749cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages)
3750{
3751 int rc = 0;
3752 struct page *page;
3753 unsigned int i;
3754
3755 for (i = 0; i < nr_pages; i++) {
3756 page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
3757 if (!page) {
3758 rc = -ENOMEM;
3759 break;
3760 }
3761 rdata->pages[i] = page;
3762 }
3763
3764 if (rc) {
3765 unsigned int nr_page_failed = i;
3766
3767 for (i = 0; i < nr_page_failed; i++) {
3768 put_page(rdata->pages[i]);
3769 rdata->pages[i] = NULL;
3770 }
3771 }
3772 return rc;
3773}
3774
3775static void
3776cifs_uncached_readdata_release(struct kref *refcount)
3777{
3778 struct cifs_readdata *rdata = container_of(refcount,
3779 struct cifs_readdata, refcount);
3780 unsigned int i;
3781
3782 kref_put(&rdata->ctx->refcount, cifs_aio_ctx_release);
3783 for (i = 0; i < rdata->nr_pages; i++) {
3784 put_page(rdata->pages[i]);
3785 }
3786 cifs_readdata_release(refcount);
3787}
3788
3789/**
3790 * cifs_readdata_to_iov - copy data from pages in response to an iovec
3791 * @rdata: the readdata response with list of pages holding data
3792 * @iter: destination for our data
3793 *
3794 * This function copies data from a list of pages in a readdata response into
3795 * an array of iovecs. It will first calculate where the data should go
3796 * based on the info in the readdata and then copy the data into that spot.
3797 */
3798static int
3799cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
3800{
3801 size_t remaining = rdata->got_bytes;
3802 unsigned int i;
3803
3804 for (i = 0; i < rdata->nr_pages; i++) {
3805 struct page *page = rdata->pages[i];
3806 size_t copy = min_t(size_t, remaining, PAGE_SIZE);
3807 size_t written;
3808
3809 if (unlikely(iov_iter_is_pipe(iter))) {
3810 void *addr = kmap_atomic(page);
3811
3812 written = copy_to_iter(addr, copy, iter);
3813 kunmap_atomic(addr);
3814 } else
3815 written = copy_page_to_iter(page, 0, copy, iter);
3816 remaining -= written;
3817 if (written < copy && iov_iter_count(iter) > 0)
3818 break;
3819 }
3820 return remaining ? -EFAULT : 0;
3821}
3822
3823static void collect_uncached_read_data(struct cifs_aio_ctx *ctx);
3824
3825static void
3826cifs_uncached_readv_complete(struct work_struct *work)
3827{
3828 struct cifs_readdata *rdata = container_of(work,
3829 struct cifs_readdata, work);
3830
3831 complete(&rdata->done);
3832 collect_uncached_read_data(rdata->ctx);
3833 /* the below call can possibly free the last ref to aio ctx */
3834 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
3835}
3836
3837static int
3838uncached_fill_pages(struct TCP_Server_Info *server,
3839 struct cifs_readdata *rdata, struct iov_iter *iter,
3840 unsigned int len)
3841{
3842 int result = 0;
3843 unsigned int i;
3844 unsigned int nr_pages = rdata->nr_pages;
3845 unsigned int page_offset = rdata->page_offset;
3846
3847 rdata->got_bytes = 0;
3848 rdata->tailsz = PAGE_SIZE;
3849 for (i = 0; i < nr_pages; i++) {
3850 struct page *page = rdata->pages[i];
3851 size_t n;
3852 unsigned int segment_size = rdata->pagesz;
3853
3854 if (i == 0)
3855 segment_size -= page_offset;
3856 else
3857 page_offset = 0;
3858
3859
3860 if (len <= 0) {
3861 /* no need to hold page hostage */
3862 rdata->pages[i] = NULL;
3863 rdata->nr_pages--;
3864 put_page(page);
3865 continue;
3866 }
3867
3868 n = len;
3869 if (len >= segment_size)
3870 /* enough data to fill the page */
3871 n = segment_size;
3872 else
3873 rdata->tailsz = len;
3874 len -= n;
3875
3876 if (iter)
3877 result = copy_page_from_iter(
3878 page, page_offset, n, iter);
3879#ifdef CONFIG_CIFS_SMB_DIRECT
3880 else if (rdata->mr)
3881 result = n;
3882#endif
3883 else
3884 result = cifs_read_page_from_socket(
3885 server, page, page_offset, n);
3886 if (result < 0)
3887 break;
3888
3889 rdata->got_bytes += result;
3890 }
3891
3892 return result != -ECONNABORTED && rdata->got_bytes > 0 ?
3893 rdata->got_bytes : result;
3894}
3895
3896static int
3897cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
3898 struct cifs_readdata *rdata, unsigned int len)
3899{
3900 return uncached_fill_pages(server, rdata, NULL, len);
3901}
3902
3903static int
3904cifs_uncached_copy_into_pages(struct TCP_Server_Info *server,
3905 struct cifs_readdata *rdata,
3906 struct iov_iter *iter)
3907{
3908 return uncached_fill_pages(server, rdata, iter, iter->count);
3909}
3910
3911static int cifs_resend_rdata(struct cifs_readdata *rdata,
3912 struct list_head *rdata_list,
3913 struct cifs_aio_ctx *ctx)
3914{
3915 unsigned int rsize;
3916 struct cifs_credits credits;
3917 int rc;
3918 struct TCP_Server_Info *server;
3919
3920 /* XXX: should we pick a new channel here? */
3921 server = rdata->server;
3922
3923 do {
3924 if (rdata->cfile->invalidHandle) {
3925 rc = cifs_reopen_file(rdata->cfile, true);
3926 if (rc == -EAGAIN)
3927 continue;
3928 else if (rc)
3929 break;
3930 }
3931
3932 /*
3933 * Wait for credits to resend this rdata.
3934 * Note: we are attempting to resend the whole rdata not in
3935 * segments
3936 */
3937 do {
3938 rc = server->ops->wait_mtu_credits(server, rdata->bytes,
3939 &rsize, &credits);
3940
3941 if (rc)
3942 goto fail;
3943
3944 if (rsize < rdata->bytes) {
3945 add_credits_and_wake_if(server, &credits, 0);
3946 msleep(1000);
3947 }
3948 } while (rsize < rdata->bytes);
3949 rdata->credits = credits;
3950
3951 rc = adjust_credits(server, &rdata->credits, rdata->bytes);
3952 if (!rc) {
3953 if (rdata->cfile->invalidHandle)
3954 rc = -EAGAIN;
3955 else {
3956#ifdef CONFIG_CIFS_SMB_DIRECT
3957 if (rdata->mr) {
3958 rdata->mr->need_invalidate = true;
3959 smbd_deregister_mr(rdata->mr);
3960 rdata->mr = NULL;
3961 }
3962#endif
3963 rc = server->ops->async_readv(rdata);
3964 }
3965 }
3966
3967 /* If the read was successfully sent, we are done */
3968 if (!rc) {
3969 /* Add to aio pending list */
3970 list_add_tail(&rdata->list, rdata_list);
3971 return 0;
3972 }
3973
3974 /* Roll back credits and retry if needed */
3975 add_credits_and_wake_if(server, &rdata->credits, 0);
3976 } while (rc == -EAGAIN);
3977
3978fail:
3979 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
3980 return rc;
3981}
3982
3983static int
3984cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
3985 struct cifs_sb_info *cifs_sb, struct list_head *rdata_list,
3986 struct cifs_aio_ctx *ctx)
3987{
3988 struct cifs_readdata *rdata;
3989 unsigned int npages, rsize;
3990 struct cifs_credits credits_on_stack;
3991 struct cifs_credits *credits = &credits_on_stack;
3992 size_t cur_len;
3993 int rc;
3994 pid_t pid;
3995 struct TCP_Server_Info *server;
3996 struct page **pagevec;
3997 size_t start;
3998 struct iov_iter direct_iov = ctx->iter;
3999
4000 server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
4001
4002 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
4003 pid = open_file->pid;
4004 else
4005 pid = current->tgid;
4006
4007 if (ctx->direct_io)
4008 iov_iter_advance(&direct_iov, offset - ctx->pos);
4009
4010 do {
4011 if (open_file->invalidHandle) {
4012 rc = cifs_reopen_file(open_file, true);
4013 if (rc == -EAGAIN)
4014 continue;
4015 else if (rc)
4016 break;
4017 }
4018
4019 if (cifs_sb->ctx->rsize == 0)
4020 cifs_sb->ctx->rsize =
4021 server->ops->negotiate_rsize(tlink_tcon(open_file->tlink),
4022 cifs_sb->ctx);
4023
4024 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
4025 &rsize, credits);
4026 if (rc)
4027 break;
4028
4029 cur_len = min_t(const size_t, len, rsize);
4030
4031 if (ctx->direct_io) {
4032 ssize_t result;
4033
4034 result = iov_iter_get_pages_alloc2(
4035 &direct_iov, &pagevec,
4036 cur_len, &start);
4037 if (result < 0) {
4038 cifs_dbg(VFS,
4039 "Couldn't get user pages (rc=%zd) iter type %d iov_offset %zd count %zd\n",
4040 result, iov_iter_type(&direct_iov),
4041 direct_iov.iov_offset,
4042 direct_iov.count);
4043 dump_stack();
4044
4045 rc = result;
4046 add_credits_and_wake_if(server, credits, 0);
4047 break;
4048 }
4049 cur_len = (size_t)result;
4050
4051 rdata = cifs_readdata_direct_alloc(
4052 pagevec, cifs_uncached_readv_complete);
4053 if (!rdata) {
4054 add_credits_and_wake_if(server, credits, 0);
4055 rc = -ENOMEM;
4056 break;
4057 }
4058
4059 npages = (cur_len + start + PAGE_SIZE-1) / PAGE_SIZE;
4060 rdata->page_offset = start;
4061 rdata->tailsz = npages > 1 ?
4062 cur_len-(PAGE_SIZE-start)-(npages-2)*PAGE_SIZE :
4063 cur_len;
4064
4065 } else {
4066
4067 npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
4068 /* allocate a readdata struct */
4069 rdata = cifs_readdata_alloc(npages,
4070 cifs_uncached_readv_complete);
4071 if (!rdata) {
4072 add_credits_and_wake_if(server, credits, 0);
4073 rc = -ENOMEM;
4074 break;
4075 }
4076
4077 rc = cifs_read_allocate_pages(rdata, npages);
4078 if (rc) {
4079 kvfree(rdata->pages);
4080 kfree(rdata);
4081 add_credits_and_wake_if(server, credits, 0);
4082 break;
4083 }
4084
4085 rdata->tailsz = PAGE_SIZE;
4086 }
4087
4088 rdata->server = server;
4089 rdata->cfile = cifsFileInfo_get(open_file);
4090 rdata->nr_pages = npages;
4091 rdata->offset = offset;
4092 rdata->bytes = cur_len;
4093 rdata->pid = pid;
4094 rdata->pagesz = PAGE_SIZE;
4095 rdata->read_into_pages = cifs_uncached_read_into_pages;
4096 rdata->copy_into_pages = cifs_uncached_copy_into_pages;
4097 rdata->credits = credits_on_stack;
4098 rdata->ctx = ctx;
4099 kref_get(&ctx->refcount);
4100
4101 rc = adjust_credits(server, &rdata->credits, rdata->bytes);
4102
4103 if (!rc) {
4104 if (rdata->cfile->invalidHandle)
4105 rc = -EAGAIN;
4106 else
4107 rc = server->ops->async_readv(rdata);
4108 }
4109
4110 if (rc) {
4111 add_credits_and_wake_if(server, &rdata->credits, 0);
4112 kref_put(&rdata->refcount,
4113 cifs_uncached_readdata_release);
4114 if (rc == -EAGAIN) {
4115 iov_iter_revert(&direct_iov, cur_len);
4116 continue;
4117 }
4118 break;
4119 }
4120
4121 list_add_tail(&rdata->list, rdata_list);
4122 offset += cur_len;
4123 len -= cur_len;
4124 } while (len > 0);
4125
4126 return rc;
4127}
4128
4129static void
4130collect_uncached_read_data(struct cifs_aio_ctx *ctx)
4131{
4132 struct cifs_readdata *rdata, *tmp;
4133 struct iov_iter *to = &ctx->iter;
4134 struct cifs_sb_info *cifs_sb;
4135 int rc;
4136
4137 cifs_sb = CIFS_SB(ctx->cfile->dentry->d_sb);
4138
4139 mutex_lock(&ctx->aio_mutex);
4140
4141 if (list_empty(&ctx->list)) {
4142 mutex_unlock(&ctx->aio_mutex);
4143 return;
4144 }
4145
4146 rc = ctx->rc;
4147 /* the loop below should proceed in the order of increasing offsets */
4148again:
4149 list_for_each_entry_safe(rdata, tmp, &ctx->list, list) {
4150 if (!rc) {
4151 if (!try_wait_for_completion(&rdata->done)) {
4152 mutex_unlock(&ctx->aio_mutex);
4153 return;
4154 }
4155
4156 if (rdata->result == -EAGAIN) {
4157 /* resend call if it's a retryable error */
4158 struct list_head tmp_list;
4159 unsigned int got_bytes = rdata->got_bytes;
4160
4161 list_del_init(&rdata->list);
4162 INIT_LIST_HEAD(&tmp_list);
4163
4164 /*
4165 * Got a part of data and then reconnect has
4166 * happened -- fill the buffer and continue
4167 * reading.
4168 */
4169 if (got_bytes && got_bytes < rdata->bytes) {
4170 rc = 0;
4171 if (!ctx->direct_io)
4172 rc = cifs_readdata_to_iov(rdata, to);
4173 if (rc) {
4174 kref_put(&rdata->refcount,
4175 cifs_uncached_readdata_release);
4176 continue;
4177 }
4178 }
4179
4180 if (ctx->direct_io) {
4181 /*
4182 * Re-use rdata as this is a
4183 * direct I/O
4184 */
4185 rc = cifs_resend_rdata(
4186 rdata,
4187 &tmp_list, ctx);
4188 } else {
4189 rc = cifs_send_async_read(
4190 rdata->offset + got_bytes,
4191 rdata->bytes - got_bytes,
4192 rdata->cfile, cifs_sb,
4193 &tmp_list, ctx);
4194
4195 kref_put(&rdata->refcount,
4196 cifs_uncached_readdata_release);
4197 }
4198
4199 list_splice(&tmp_list, &ctx->list);
4200
4201 goto again;
4202 } else if (rdata->result)
4203 rc = rdata->result;
4204 else if (!ctx->direct_io)
4205 rc = cifs_readdata_to_iov(rdata, to);
4206
4207 /* if there was a short read -- discard anything left */
4208 if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
4209 rc = -ENODATA;
4210
4211 ctx->total_len += rdata->got_bytes;
4212 }
4213 list_del_init(&rdata->list);
4214 kref_put(&rdata->refcount, cifs_uncached_readdata_release);
4215 }
4216
4217 if (!ctx->direct_io)
4218 ctx->total_len = ctx->len - iov_iter_count(to);
4219
4220 /* mask nodata case */
4221 if (rc == -ENODATA)
4222 rc = 0;
4223
4224 ctx->rc = (rc == 0) ? (ssize_t)ctx->total_len : rc;
4225
4226 mutex_unlock(&ctx->aio_mutex);
4227
4228 if (ctx->iocb && ctx->iocb->ki_complete)
4229 ctx->iocb->ki_complete(ctx->iocb, ctx->rc);
4230 else
4231 complete(&ctx->done);
4232}
4233
4234static ssize_t __cifs_readv(
4235 struct kiocb *iocb, struct iov_iter *to, bool direct)
4236{
4237 size_t len;
4238 struct file *file = iocb->ki_filp;
4239 struct cifs_sb_info *cifs_sb;
4240 struct cifsFileInfo *cfile;
4241 struct cifs_tcon *tcon;
4242 ssize_t rc, total_read = 0;
4243 loff_t offset = iocb->ki_pos;
4244 struct cifs_aio_ctx *ctx;
4245
4246 /*
4247 * iov_iter_get_pages_alloc() doesn't work with ITER_KVEC,
4248 * fall back to data copy read path
4249 * this could be improved by getting pages directly in ITER_KVEC
4250 */
4251 if (direct && iov_iter_is_kvec(to)) {
4252 cifs_dbg(FYI, "use non-direct cifs_user_readv for kvec I/O\n");
4253 direct = false;
4254 }
4255
4256 len = iov_iter_count(to);
4257 if (!len)
4258 return 0;
4259
4260 cifs_sb = CIFS_FILE_SB(file);
4261 cfile = file->private_data;
4262 tcon = tlink_tcon(cfile->tlink);
4263
4264 if (!tcon->ses->server->ops->async_readv)
4265 return -ENOSYS;
4266
4267 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
4268 cifs_dbg(FYI, "attempting read on write only file instance\n");
4269
4270 ctx = cifs_aio_ctx_alloc();
4271 if (!ctx)
4272 return -ENOMEM;
4273
4274 ctx->cfile = cifsFileInfo_get(cfile);
4275
4276 if (!is_sync_kiocb(iocb))
4277 ctx->iocb = iocb;
4278
4279 if (user_backed_iter(to))
4280 ctx->should_dirty = true;
4281
4282 if (direct) {
4283 ctx->pos = offset;
4284 ctx->direct_io = true;
4285 ctx->iter = *to;
4286 ctx->len = len;
4287 } else {
4288 rc = setup_aio_ctx_iter(ctx, to, ITER_DEST);
4289 if (rc) {
4290 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4291 return rc;
4292 }
4293 len = ctx->len;
4294 }
4295
4296 if (direct) {
4297 rc = filemap_write_and_wait_range(file->f_inode->i_mapping,
4298 offset, offset + len - 1);
4299 if (rc) {
4300 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4301 return -EAGAIN;
4302 }
4303 }
4304
4305 /* grab a lock here due to read response handlers can access ctx */
4306 mutex_lock(&ctx->aio_mutex);
4307
4308 rc = cifs_send_async_read(offset, len, cfile, cifs_sb, &ctx->list, ctx);
4309
4310 /* if at least one read request send succeeded, then reset rc */
4311 if (!list_empty(&ctx->list))
4312 rc = 0;
4313
4314 mutex_unlock(&ctx->aio_mutex);
4315
4316 if (rc) {
4317 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4318 return rc;
4319 }
4320
4321 if (!is_sync_kiocb(iocb)) {
4322 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4323 return -EIOCBQUEUED;
4324 }
4325
4326 rc = wait_for_completion_killable(&ctx->done);
4327 if (rc) {
4328 mutex_lock(&ctx->aio_mutex);
4329 ctx->rc = rc = -EINTR;
4330 total_read = ctx->total_len;
4331 mutex_unlock(&ctx->aio_mutex);
4332 } else {
4333 rc = ctx->rc;
4334 total_read = ctx->total_len;
4335 }
4336
4337 kref_put(&ctx->refcount, cifs_aio_ctx_release);
4338
4339 if (total_read) {
4340 iocb->ki_pos += total_read;
4341 return total_read;
4342 }
4343 return rc;
4344}
4345
4346ssize_t cifs_direct_readv(struct kiocb *iocb, struct iov_iter *to)
4347{
4348 return __cifs_readv(iocb, to, true);
4349}
4350
4351ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
4352{
4353 return __cifs_readv(iocb, to, false);
4354}
4355
4356ssize_t
4357cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
4358{
4359 struct inode *inode = file_inode(iocb->ki_filp);
4360 struct cifsInodeInfo *cinode = CIFS_I(inode);
4361 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
4362 struct cifsFileInfo *cfile = (struct cifsFileInfo *)
4363 iocb->ki_filp->private_data;
4364 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
4365 int rc = -EACCES;
4366
4367 /*
4368 * In strict cache mode we need to read from the server all the time
4369 * if we don't have level II oplock because the server can delay mtime
4370 * change - so we can't make a decision about inode invalidating.
4371 * And we can also fail with pagereading if there are mandatory locks
4372 * on pages affected by this read but not on the region from pos to
4373 * pos+len-1.
4374 */
4375 if (!CIFS_CACHE_READ(cinode))
4376 return cifs_user_readv(iocb, to);
4377
4378 if (cap_unix(tcon->ses) &&
4379 (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
4380 ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
4381 return generic_file_read_iter(iocb, to);
4382
4383 /*
4384 * We need to hold the sem to be sure nobody modifies lock list
4385 * with a brlock that prevents reading.
4386 */
4387 down_read(&cinode->lock_sem);
4388 if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(to),
4389 tcon->ses->server->vals->shared_lock_type,
4390 0, NULL, CIFS_READ_OP))
4391 rc = generic_file_read_iter(iocb, to);
4392 up_read(&cinode->lock_sem);
4393 return rc;
4394}
4395
4396static ssize_t
4397cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
4398{
4399 int rc = -EACCES;
4400 unsigned int bytes_read = 0;
4401 unsigned int total_read;
4402 unsigned int current_read_size;
4403 unsigned int rsize;
4404 struct cifs_sb_info *cifs_sb;
4405 struct cifs_tcon *tcon;
4406 struct TCP_Server_Info *server;
4407 unsigned int xid;
4408 char *cur_offset;
4409 struct cifsFileInfo *open_file;
4410 struct cifs_io_parms io_parms = {0};
4411 int buf_type = CIFS_NO_BUFFER;
4412 __u32 pid;
4413
4414 xid = get_xid();
4415 cifs_sb = CIFS_FILE_SB(file);
4416
4417 /* FIXME: set up handlers for larger reads and/or convert to async */
4418 rsize = min_t(unsigned int, cifs_sb->ctx->rsize, CIFSMaxBufSize);
4419
4420 if (file->private_data == NULL) {
4421 rc = -EBADF;
4422 free_xid(xid);
4423 return rc;
4424 }
4425 open_file = file->private_data;
4426 tcon = tlink_tcon(open_file->tlink);
4427 server = cifs_pick_channel(tcon->ses);
4428
4429 if (!server->ops->sync_read) {
4430 free_xid(xid);
4431 return -ENOSYS;
4432 }
4433
4434 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
4435 pid = open_file->pid;
4436 else
4437 pid = current->tgid;
4438
4439 if ((file->f_flags & O_ACCMODE) == O_WRONLY)
4440 cifs_dbg(FYI, "attempting read on write only file instance\n");
4441
4442 for (total_read = 0, cur_offset = read_data; read_size > total_read;
4443 total_read += bytes_read, cur_offset += bytes_read) {
4444 do {
4445 current_read_size = min_t(uint, read_size - total_read,
4446 rsize);
4447 /*
4448 * For windows me and 9x we do not want to request more
4449 * than it negotiated since it will refuse the read
4450 * then.
4451 */
4452 if (!(tcon->ses->capabilities &
4453 tcon->ses->server->vals->cap_large_files)) {
4454 current_read_size = min_t(uint,
4455 current_read_size, CIFSMaxBufSize);
4456 }
4457 if (open_file->invalidHandle) {
4458 rc = cifs_reopen_file(open_file, true);
4459 if (rc != 0)
4460 break;
4461 }
4462 io_parms.pid = pid;
4463 io_parms.tcon = tcon;
4464 io_parms.offset = *offset;
4465 io_parms.length = current_read_size;
4466 io_parms.server = server;
4467 rc = server->ops->sync_read(xid, &open_file->fid, &io_parms,
4468 &bytes_read, &cur_offset,
4469 &buf_type);
4470 } while (rc == -EAGAIN);
4471
4472 if (rc || (bytes_read == 0)) {
4473 if (total_read) {
4474 break;
4475 } else {
4476 free_xid(xid);
4477 return rc;
4478 }
4479 } else {
4480 cifs_stats_bytes_read(tcon, total_read);
4481 *offset += bytes_read;
4482 }
4483 }
4484 free_xid(xid);
4485 return total_read;
4486}
4487
4488/*
4489 * If the page is mmap'ed into a process' page tables, then we need to make
4490 * sure that it doesn't change while being written back.
4491 */
4492static vm_fault_t
4493cifs_page_mkwrite(struct vm_fault *vmf)
4494{
4495 struct page *page = vmf->page;
4496
4497 /* Wait for the page to be written to the cache before we allow it to
4498 * be modified. We then assume the entire page will need writing back.
4499 */
4500#ifdef CONFIG_CIFS_FSCACHE
4501 if (PageFsCache(page) &&
4502 wait_on_page_fscache_killable(page) < 0)
4503 return VM_FAULT_RETRY;
4504#endif
4505
4506 wait_on_page_writeback(page);
4507
4508 if (lock_page_killable(page) < 0)
4509 return VM_FAULT_RETRY;
4510 return VM_FAULT_LOCKED;
4511}
4512
4513static const struct vm_operations_struct cifs_file_vm_ops = {
4514 .fault = filemap_fault,
4515 .map_pages = filemap_map_pages,
4516 .page_mkwrite = cifs_page_mkwrite,
4517};
4518
4519int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
4520{
4521 int xid, rc = 0;
4522 struct inode *inode = file_inode(file);
4523
4524 xid = get_xid();
4525
4526 if (!CIFS_CACHE_READ(CIFS_I(inode)))
4527 rc = cifs_zap_mapping(inode);
4528 if (!rc)
4529 rc = generic_file_mmap(file, vma);
4530 if (!rc)
4531 vma->vm_ops = &cifs_file_vm_ops;
4532
4533 free_xid(xid);
4534 return rc;
4535}
4536
4537int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
4538{
4539 int rc, xid;
4540
4541 xid = get_xid();
4542
4543 rc = cifs_revalidate_file(file);
4544 if (rc)
4545 cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
4546 rc);
4547 if (!rc)
4548 rc = generic_file_mmap(file, vma);
4549 if (!rc)
4550 vma->vm_ops = &cifs_file_vm_ops;
4551
4552 free_xid(xid);
4553 return rc;
4554}
4555
4556static void
4557cifs_readv_complete(struct work_struct *work)
4558{
4559 unsigned int i, got_bytes;
4560 struct cifs_readdata *rdata = container_of(work,
4561 struct cifs_readdata, work);
4562
4563 got_bytes = rdata->got_bytes;
4564 for (i = 0; i < rdata->nr_pages; i++) {
4565 struct page *page = rdata->pages[i];
4566
4567 if (rdata->result == 0 ||
4568 (rdata->result == -EAGAIN && got_bytes)) {
4569 flush_dcache_page(page);
4570 SetPageUptodate(page);
4571 } else
4572 SetPageError(page);
4573
4574 if (rdata->result == 0 ||
4575 (rdata->result == -EAGAIN && got_bytes))
4576 cifs_readpage_to_fscache(rdata->mapping->host, page);
4577
4578 unlock_page(page);
4579
4580 got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
4581
4582 put_page(page);
4583 rdata->pages[i] = NULL;
4584 }
4585 kref_put(&rdata->refcount, cifs_readdata_release);
4586}
4587
4588static int
4589readpages_fill_pages(struct TCP_Server_Info *server,
4590 struct cifs_readdata *rdata, struct iov_iter *iter,
4591 unsigned int len)
4592{
4593 int result = 0;
4594 unsigned int i;
4595 u64 eof;
4596 pgoff_t eof_index;
4597 unsigned int nr_pages = rdata->nr_pages;
4598 unsigned int page_offset = rdata->page_offset;
4599
4600 /* determine the eof that the server (probably) has */
4601 eof = CIFS_I(rdata->mapping->host)->server_eof;
4602 eof_index = eof ? (eof - 1) >> PAGE_SHIFT : 0;
4603 cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
4604
4605 rdata->got_bytes = 0;
4606 rdata->tailsz = PAGE_SIZE;
4607 for (i = 0; i < nr_pages; i++) {
4608 struct page *page = rdata->pages[i];
4609 unsigned int to_read = rdata->pagesz;
4610 size_t n;
4611
4612 if (i == 0)
4613 to_read -= page_offset;
4614 else
4615 page_offset = 0;
4616
4617 n = to_read;
4618
4619 if (len >= to_read) {
4620 len -= to_read;
4621 } else if (len > 0) {
4622 /* enough for partial page, fill and zero the rest */
4623 zero_user(page, len + page_offset, to_read - len);
4624 n = rdata->tailsz = len;
4625 len = 0;
4626 } else if (page->index > eof_index) {
4627 /*
4628 * The VFS will not try to do readahead past the
4629 * i_size, but it's possible that we have outstanding
4630 * writes with gaps in the middle and the i_size hasn't
4631 * caught up yet. Populate those with zeroed out pages
4632 * to prevent the VFS from repeatedly attempting to
4633 * fill them until the writes are flushed.
4634 */
4635 zero_user(page, 0, PAGE_SIZE);
4636 flush_dcache_page(page);
4637 SetPageUptodate(page);
4638 unlock_page(page);
4639 put_page(page);
4640 rdata->pages[i] = NULL;
4641 rdata->nr_pages--;
4642 continue;
4643 } else {
4644 /* no need to hold page hostage */
4645 unlock_page(page);
4646 put_page(page);
4647 rdata->pages[i] = NULL;
4648 rdata->nr_pages--;
4649 continue;
4650 }
4651
4652 if (iter)
4653 result = copy_page_from_iter(
4654 page, page_offset, n, iter);
4655#ifdef CONFIG_CIFS_SMB_DIRECT
4656 else if (rdata->mr)
4657 result = n;
4658#endif
4659 else
4660 result = cifs_read_page_from_socket(
4661 server, page, page_offset, n);
4662 if (result < 0)
4663 break;
4664
4665 rdata->got_bytes += result;
4666 }
4667
4668 return result != -ECONNABORTED && rdata->got_bytes > 0 ?
4669 rdata->got_bytes : result;
4670}
4671
4672static int
4673cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
4674 struct cifs_readdata *rdata, unsigned int len)
4675{
4676 return readpages_fill_pages(server, rdata, NULL, len);
4677}
4678
4679static int
4680cifs_readpages_copy_into_pages(struct TCP_Server_Info *server,
4681 struct cifs_readdata *rdata,
4682 struct iov_iter *iter)
4683{
4684 return readpages_fill_pages(server, rdata, iter, iter->count);
4685}
4686
4687static void cifs_readahead(struct readahead_control *ractl)
4688{
4689 int rc;
4690 struct cifsFileInfo *open_file = ractl->file->private_data;
4691 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(ractl->file);
4692 struct TCP_Server_Info *server;
4693 pid_t pid;
4694 unsigned int xid, nr_pages, last_batch_size = 0, cache_nr_pages = 0;
4695 pgoff_t next_cached = ULONG_MAX;
4696 bool caching = fscache_cookie_enabled(cifs_inode_cookie(ractl->mapping->host)) &&
4697 cifs_inode_cookie(ractl->mapping->host)->cache_priv;
4698 bool check_cache = caching;
4699
4700 xid = get_xid();
4701
4702 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
4703 pid = open_file->pid;
4704 else
4705 pid = current->tgid;
4706
4707 rc = 0;
4708 server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
4709
4710 cifs_dbg(FYI, "%s: file=%p mapping=%p num_pages=%u\n",
4711 __func__, ractl->file, ractl->mapping, readahead_count(ractl));
4712
4713 /*
4714 * Chop the readahead request up into rsize-sized read requests.
4715 */
4716 while ((nr_pages = readahead_count(ractl) - last_batch_size)) {
4717 unsigned int i, got, rsize;
4718 struct page *page;
4719 struct cifs_readdata *rdata;
4720 struct cifs_credits credits_on_stack;
4721 struct cifs_credits *credits = &credits_on_stack;
4722 pgoff_t index = readahead_index(ractl) + last_batch_size;
4723
4724 /*
4725 * Find out if we have anything cached in the range of
4726 * interest, and if so, where the next chunk of cached data is.
4727 */
4728 if (caching) {
4729 if (check_cache) {
4730 rc = cifs_fscache_query_occupancy(
4731 ractl->mapping->host, index, nr_pages,
4732 &next_cached, &cache_nr_pages);
4733 if (rc < 0)
4734 caching = false;
4735 check_cache = false;
4736 }
4737
4738 if (index == next_cached) {
4739 /*
4740 * TODO: Send a whole batch of pages to be read
4741 * by the cache.
4742 */
4743 struct folio *folio = readahead_folio(ractl);
4744
4745 last_batch_size = folio_nr_pages(folio);
4746 if (cifs_readpage_from_fscache(ractl->mapping->host,
4747 &folio->page) < 0) {
4748 /*
4749 * TODO: Deal with cache read failure
4750 * here, but for the moment, delegate
4751 * that to readpage.
4752 */
4753 caching = false;
4754 }
4755 folio_unlock(folio);
4756 next_cached++;
4757 cache_nr_pages--;
4758 if (cache_nr_pages == 0)
4759 check_cache = true;
4760 continue;
4761 }
4762 }
4763
4764 if (open_file->invalidHandle) {
4765 rc = cifs_reopen_file(open_file, true);
4766 if (rc) {
4767 if (rc == -EAGAIN)
4768 continue;
4769 break;
4770 }
4771 }
4772
4773 if (cifs_sb->ctx->rsize == 0)
4774 cifs_sb->ctx->rsize =
4775 server->ops->negotiate_rsize(tlink_tcon(open_file->tlink),
4776 cifs_sb->ctx);
4777
4778 rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
4779 &rsize, credits);
4780 if (rc)
4781 break;
4782 nr_pages = min_t(size_t, rsize / PAGE_SIZE, readahead_count(ractl));
4783 nr_pages = min_t(size_t, nr_pages, next_cached - index);
4784
4785 /*
4786 * Give up immediately if rsize is too small to read an entire
4787 * page. The VFS will fall back to readpage. We should never
4788 * reach this point however since we set ra_pages to 0 when the
4789 * rsize is smaller than a cache page.
4790 */
4791 if (unlikely(!nr_pages)) {
4792 add_credits_and_wake_if(server, credits, 0);
4793 break;
4794 }
4795
4796 rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
4797 if (!rdata) {
4798 /* best to give up if we're out of mem */
4799 add_credits_and_wake_if(server, credits, 0);
4800 break;
4801 }
4802
4803 got = __readahead_batch(ractl, rdata->pages, nr_pages);
4804 if (got != nr_pages) {
4805 pr_warn("__readahead_batch() returned %u/%u\n",
4806 got, nr_pages);
4807 nr_pages = got;
4808 }
4809
4810 rdata->nr_pages = nr_pages;
4811 rdata->bytes = readahead_batch_length(ractl);
4812 rdata->cfile = cifsFileInfo_get(open_file);
4813 rdata->server = server;
4814 rdata->mapping = ractl->mapping;
4815 rdata->offset = readahead_pos(ractl);
4816 rdata->pid = pid;
4817 rdata->pagesz = PAGE_SIZE;
4818 rdata->tailsz = PAGE_SIZE;
4819 rdata->read_into_pages = cifs_readpages_read_into_pages;
4820 rdata->copy_into_pages = cifs_readpages_copy_into_pages;
4821 rdata->credits = credits_on_stack;
4822
4823 rc = adjust_credits(server, &rdata->credits, rdata->bytes);
4824 if (!rc) {
4825 if (rdata->cfile->invalidHandle)
4826 rc = -EAGAIN;
4827 else
4828 rc = server->ops->async_readv(rdata);
4829 }
4830
4831 if (rc) {
4832 add_credits_and_wake_if(server, &rdata->credits, 0);
4833 for (i = 0; i < rdata->nr_pages; i++) {
4834 page = rdata->pages[i];
4835 unlock_page(page);
4836 put_page(page);
4837 }
4838 /* Fallback to the readpage in error/reconnect cases */
4839 kref_put(&rdata->refcount, cifs_readdata_release);
4840 break;
4841 }
4842
4843 kref_put(&rdata->refcount, cifs_readdata_release);
4844 last_batch_size = nr_pages;
4845 }
4846
4847 free_xid(xid);
4848}
4849
4850/*
4851 * cifs_readpage_worker must be called with the page pinned
4852 */
4853static int cifs_readpage_worker(struct file *file, struct page *page,
4854 loff_t *poffset)
4855{
4856 char *read_data;
4857 int rc;
4858
4859 /* Is the page cached? */
4860 rc = cifs_readpage_from_fscache(file_inode(file), page);
4861 if (rc == 0)
4862 goto read_complete;
4863
4864 read_data = kmap(page);
4865 /* for reads over a certain size could initiate async read ahead */
4866
4867 rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
4868
4869 if (rc < 0)
4870 goto io_error;
4871 else
4872 cifs_dbg(FYI, "Bytes read %d\n", rc);
4873
4874 /* we do not want atime to be less than mtime, it broke some apps */
4875 file_inode(file)->i_atime = current_time(file_inode(file));
4876 if (timespec64_compare(&(file_inode(file)->i_atime), &(file_inode(file)->i_mtime)))
4877 file_inode(file)->i_atime = file_inode(file)->i_mtime;
4878 else
4879 file_inode(file)->i_atime = current_time(file_inode(file));
4880
4881 if (PAGE_SIZE > rc)
4882 memset(read_data + rc, 0, PAGE_SIZE - rc);
4883
4884 flush_dcache_page(page);
4885 SetPageUptodate(page);
4886
4887 /* send this page to the cache */
4888 cifs_readpage_to_fscache(file_inode(file), page);
4889
4890 rc = 0;
4891
4892io_error:
4893 kunmap(page);
4894 unlock_page(page);
4895
4896read_complete:
4897 return rc;
4898}
4899
4900static int cifs_read_folio(struct file *file, struct folio *folio)
4901{
4902 struct page *page = &folio->page;
4903 loff_t offset = page_file_offset(page);
4904 int rc = -EACCES;
4905 unsigned int xid;
4906
4907 xid = get_xid();
4908
4909 if (file->private_data == NULL) {
4910 rc = -EBADF;
4911 free_xid(xid);
4912 return rc;
4913 }
4914
4915 cifs_dbg(FYI, "read_folio %p at offset %d 0x%x\n",
4916 page, (int)offset, (int)offset);
4917
4918 rc = cifs_readpage_worker(file, page, &offset);
4919
4920 free_xid(xid);
4921 return rc;
4922}
4923
4924static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
4925{
4926 struct cifsFileInfo *open_file;
4927
4928 spin_lock(&cifs_inode->open_file_lock);
4929 list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
4930 if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
4931 spin_unlock(&cifs_inode->open_file_lock);
4932 return 1;
4933 }
4934 }
4935 spin_unlock(&cifs_inode->open_file_lock);
4936 return 0;
4937}
4938
4939/* We do not want to update the file size from server for inodes
4940 open for write - to avoid races with writepage extending
4941 the file - in the future we could consider allowing
4942 refreshing the inode only on increases in the file size
4943 but this is tricky to do without racing with writebehind
4944 page caching in the current Linux kernel design */
4945bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
4946{
4947 if (!cifsInode)
4948 return true;
4949
4950 if (is_inode_writable(cifsInode)) {
4951 /* This inode is open for write at least once */
4952 struct cifs_sb_info *cifs_sb;
4953
4954 cifs_sb = CIFS_SB(cifsInode->netfs.inode.i_sb);
4955 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
4956 /* since no page cache to corrupt on directio
4957 we can change size safely */
4958 return true;
4959 }
4960
4961 if (i_size_read(&cifsInode->netfs.inode) < end_of_file)
4962 return true;
4963
4964 return false;
4965 } else
4966 return true;
4967}
4968
4969static int cifs_write_begin(struct file *file, struct address_space *mapping,
4970 loff_t pos, unsigned len,
4971 struct page **pagep, void **fsdata)
4972{
4973 int oncethru = 0;
4974 pgoff_t index = pos >> PAGE_SHIFT;
4975 loff_t offset = pos & (PAGE_SIZE - 1);
4976 loff_t page_start = pos & PAGE_MASK;
4977 loff_t i_size;
4978 struct page *page;
4979 int rc = 0;
4980
4981 cifs_dbg(FYI, "write_begin from %lld len %d\n", (long long)pos, len);
4982
4983start:
4984 page = grab_cache_page_write_begin(mapping, index);
4985 if (!page) {
4986 rc = -ENOMEM;
4987 goto out;
4988 }
4989
4990 if (PageUptodate(page))
4991 goto out;
4992
4993 /*
4994 * If we write a full page it will be up to date, no need to read from
4995 * the server. If the write is short, we'll end up doing a sync write
4996 * instead.
4997 */
4998 if (len == PAGE_SIZE)
4999 goto out;
5000
5001 /*
5002 * optimize away the read when we have an oplock, and we're not
5003 * expecting to use any of the data we'd be reading in. That
5004 * is, when the page lies beyond the EOF, or straddles the EOF
5005 * and the write will cover all of the existing data.
5006 */
5007 if (CIFS_CACHE_READ(CIFS_I(mapping->host))) {
5008 i_size = i_size_read(mapping->host);
5009 if (page_start >= i_size ||
5010 (offset == 0 && (pos + len) >= i_size)) {
5011 zero_user_segments(page, 0, offset,
5012 offset + len,
5013 PAGE_SIZE);
5014 /*
5015 * PageChecked means that the parts of the page
5016 * to which we're not writing are considered up
5017 * to date. Once the data is copied to the
5018 * page, it can be set uptodate.
5019 */
5020 SetPageChecked(page);
5021 goto out;
5022 }
5023 }
5024
5025 if ((file->f_flags & O_ACCMODE) != O_WRONLY && !oncethru) {
5026 /*
5027 * might as well read a page, it is fast enough. If we get
5028 * an error, we don't need to return it. cifs_write_end will
5029 * do a sync write instead since PG_uptodate isn't set.
5030 */
5031 cifs_readpage_worker(file, page, &page_start);
5032 put_page(page);
5033 oncethru = 1;
5034 goto start;
5035 } else {
5036 /* we could try using another file handle if there is one -
5037 but how would we lock it to prevent close of that handle
5038 racing with this read? In any case
5039 this will be written out by write_end so is fine */
5040 }
5041out:
5042 *pagep = page;
5043 return rc;
5044}
5045
5046static bool cifs_release_folio(struct folio *folio, gfp_t gfp)
5047{
5048 if (folio_test_private(folio))
5049 return 0;
5050 if (folio_test_fscache(folio)) {
5051 if (current_is_kswapd() || !(gfp & __GFP_FS))
5052 return false;
5053 folio_wait_fscache(folio);
5054 }
5055 fscache_note_page_release(cifs_inode_cookie(folio->mapping->host));
5056 return true;
5057}
5058
5059static void cifs_invalidate_folio(struct folio *folio, size_t offset,
5060 size_t length)
5061{
5062 folio_wait_fscache(folio);
5063}
5064
5065static int cifs_launder_folio(struct folio *folio)
5066{
5067 int rc = 0;
5068 loff_t range_start = folio_pos(folio);
5069 loff_t range_end = range_start + folio_size(folio);
5070 struct writeback_control wbc = {
5071 .sync_mode = WB_SYNC_ALL,
5072 .nr_to_write = 0,
5073 .range_start = range_start,
5074 .range_end = range_end,
5075 };
5076
5077 cifs_dbg(FYI, "Launder page: %lu\n", folio->index);
5078
5079 if (folio_clear_dirty_for_io(folio))
5080 rc = cifs_writepage_locked(&folio->page, &wbc);
5081
5082 folio_wait_fscache(folio);
5083 return rc;
5084}
5085
5086void cifs_oplock_break(struct work_struct *work)
5087{
5088 struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
5089 oplock_break);
5090 struct inode *inode = d_inode(cfile->dentry);
5091 struct cifsInodeInfo *cinode = CIFS_I(inode);
5092 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
5093 struct TCP_Server_Info *server = tcon->ses->server;
5094 int rc = 0;
5095 bool purge_cache = false;
5096
5097 wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
5098 TASK_UNINTERRUPTIBLE);
5099
5100 server->ops->downgrade_oplock(server, cinode, cfile->oplock_level,
5101 cfile->oplock_epoch, &purge_cache);
5102
5103 if (!CIFS_CACHE_WRITE(cinode) && CIFS_CACHE_READ(cinode) &&
5104 cifs_has_mand_locks(cinode)) {
5105 cifs_dbg(FYI, "Reset oplock to None for inode=%p due to mand locks\n",
5106 inode);
5107 cinode->oplock = 0;
5108 }
5109
5110 if (inode && S_ISREG(inode->i_mode)) {
5111 if (CIFS_CACHE_READ(cinode))
5112 break_lease(inode, O_RDONLY);
5113 else
5114 break_lease(inode, O_WRONLY);
5115 rc = filemap_fdatawrite(inode->i_mapping);
5116 if (!CIFS_CACHE_READ(cinode) || purge_cache) {
5117 rc = filemap_fdatawait(inode->i_mapping);
5118 mapping_set_error(inode->i_mapping, rc);
5119 cifs_zap_mapping(inode);
5120 }
5121 cifs_dbg(FYI, "Oplock flush inode %p rc %d\n", inode, rc);
5122 if (CIFS_CACHE_WRITE(cinode))
5123 goto oplock_break_ack;
5124 }
5125
5126 rc = cifs_push_locks(cfile);
5127 if (rc)
5128 cifs_dbg(VFS, "Push locks rc = %d\n", rc);
5129
5130oplock_break_ack:
5131 /*
5132 * releasing stale oplock after recent reconnect of smb session using
5133 * a now incorrect file handle is not a data integrity issue but do
5134 * not bother sending an oplock release if session to server still is
5135 * disconnected since oplock already released by the server
5136 */
5137 if (!cfile->oplock_break_cancelled) {
5138 rc = tcon->ses->server->ops->oplock_response(tcon, &cfile->fid,
5139 cinode);
5140 cifs_dbg(FYI, "Oplock release rc = %d\n", rc);
5141 }
5142
5143 _cifsFileInfo_put(cfile, false /* do not wait for ourself */, false);
5144 cifs_done_oplock_break(cinode);
5145}
5146
5147/*
5148 * The presence of cifs_direct_io() in the address space ops vector
5149 * allowes open() O_DIRECT flags which would have failed otherwise.
5150 *
5151 * In the non-cached mode (mount with cache=none), we shunt off direct read and write requests
5152 * so this method should never be called.
5153 *
5154 * Direct IO is not yet supported in the cached mode.
5155 */
5156static ssize_t
5157cifs_direct_io(struct kiocb *iocb, struct iov_iter *iter)
5158{
5159 /*
5160 * FIXME
5161 * Eventually need to support direct IO for non forcedirectio mounts
5162 */
5163 return -EINVAL;
5164}
5165
5166static int cifs_swap_activate(struct swap_info_struct *sis,
5167 struct file *swap_file, sector_t *span)
5168{
5169 struct cifsFileInfo *cfile = swap_file->private_data;
5170 struct inode *inode = swap_file->f_mapping->host;
5171 unsigned long blocks;
5172 long long isize;
5173
5174 cifs_dbg(FYI, "swap activate\n");
5175
5176 if (!swap_file->f_mapping->a_ops->swap_rw)
5177 /* Cannot support swap */
5178 return -EINVAL;
5179
5180 spin_lock(&inode->i_lock);
5181 blocks = inode->i_blocks;
5182 isize = inode->i_size;
5183 spin_unlock(&inode->i_lock);
5184 if (blocks*512 < isize) {
5185 pr_warn("swap activate: swapfile has holes\n");
5186 return -EINVAL;
5187 }
5188 *span = sis->pages;
5189
5190 pr_warn_once("Swap support over SMB3 is experimental\n");
5191
5192 /*
5193 * TODO: consider adding ACL (or documenting how) to prevent other
5194 * users (on this or other systems) from reading it
5195 */
5196
5197
5198 /* TODO: add sk_set_memalloc(inet) or similar */
5199
5200 if (cfile)
5201 cfile->swapfile = true;
5202 /*
5203 * TODO: Since file already open, we can't open with DENY_ALL here
5204 * but we could add call to grab a byte range lock to prevent others
5205 * from reading or writing the file
5206 */
5207
5208 sis->flags |= SWP_FS_OPS;
5209 return add_swap_extent(sis, 0, sis->max, 0);
5210}
5211
5212static void cifs_swap_deactivate(struct file *file)
5213{
5214 struct cifsFileInfo *cfile = file->private_data;
5215
5216 cifs_dbg(FYI, "swap deactivate\n");
5217
5218 /* TODO: undo sk_set_memalloc(inet) will eventually be needed */
5219
5220 if (cfile)
5221 cfile->swapfile = false;
5222
5223 /* do we need to unpin (or unlock) the file */
5224}
5225
5226/*
5227 * Mark a page as having been made dirty and thus needing writeback. We also
5228 * need to pin the cache object to write back to.
5229 */
5230#ifdef CONFIG_CIFS_FSCACHE
5231static bool cifs_dirty_folio(struct address_space *mapping, struct folio *folio)
5232{
5233 return fscache_dirty_folio(mapping, folio,
5234 cifs_inode_cookie(mapping->host));
5235}
5236#else
5237#define cifs_dirty_folio filemap_dirty_folio
5238#endif
5239
5240const struct address_space_operations cifs_addr_ops = {
5241 .read_folio = cifs_read_folio,
5242 .readahead = cifs_readahead,
5243 .writepages = cifs_writepages,
5244 .write_begin = cifs_write_begin,
5245 .write_end = cifs_write_end,
5246 .dirty_folio = cifs_dirty_folio,
5247 .release_folio = cifs_release_folio,
5248 .direct_IO = cifs_direct_io,
5249 .invalidate_folio = cifs_invalidate_folio,
5250 .launder_folio = cifs_launder_folio,
5251 .migrate_folio = filemap_migrate_folio,
5252 /*
5253 * TODO: investigate and if useful we could add an is_dirty_writeback
5254 * helper if needed
5255 */
5256 .swap_activate = cifs_swap_activate,
5257 .swap_deactivate = cifs_swap_deactivate,
5258};
5259
5260/*
5261 * cifs_readahead requires the server to support a buffer large enough to
5262 * contain the header plus one complete page of data. Otherwise, we need
5263 * to leave cifs_readahead out of the address space operations.
5264 */
5265const struct address_space_operations cifs_addr_ops_smallbuf = {
5266 .read_folio = cifs_read_folio,
5267 .writepages = cifs_writepages,
5268 .write_begin = cifs_write_begin,
5269 .write_end = cifs_write_end,
5270 .dirty_folio = cifs_dirty_folio,
5271 .release_folio = cifs_release_folio,
5272 .invalidate_folio = cifs_invalidate_folio,
5273 .launder_folio = cifs_launder_folio,
5274 .migrate_folio = filemap_migrate_folio,
5275};