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1 | /* | |
2 | * fs/cifs/file.c | |
3 | * | |
4 | * vfs operations that deal with files | |
5 | * | |
6 | * Copyright (C) International Business Machines Corp., 2002,2007 | |
7 | * Author(s): Steve French (sfrench@us.ibm.com) | |
8 | * Jeremy Allison (jra@samba.org) | |
9 | * | |
10 | * This library is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU Lesser General Public License as published | |
12 | * by the Free Software Foundation; either version 2.1 of the License, or | |
13 | * (at your option) any later version. | |
14 | * | |
15 | * This library is distributed in the hope that it will be useful, | |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
18 | * the GNU Lesser General Public License for more details. | |
19 | * | |
20 | * You should have received a copy of the GNU Lesser General Public License | |
21 | * along with this library; if not, write to the Free Software | |
22 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
23 | */ | |
24 | #include <linux/fs.h> | |
25 | #include <linux/backing-dev.h> | |
26 | #include <linux/stat.h> | |
27 | #include <linux/fcntl.h> | |
28 | #include <linux/pagemap.h> | |
29 | #include <linux/pagevec.h> | |
30 | #include <linux/writeback.h> | |
31 | #include <linux/task_io_accounting_ops.h> | |
32 | #include <linux/delay.h> | |
33 | #include <asm/div64.h> | |
34 | #include "cifsfs.h" | |
35 | #include "cifspdu.h" | |
36 | #include "cifsglob.h" | |
37 | #include "cifsproto.h" | |
38 | #include "cifs_unicode.h" | |
39 | #include "cifs_debug.h" | |
40 | #include "cifs_fs_sb.h" | |
41 | ||
42 | static inline struct cifsFileInfo *cifs_init_private( | |
43 | struct cifsFileInfo *private_data, struct inode *inode, | |
44 | struct file *file, __u16 netfid) | |
45 | { | |
46 | memset(private_data, 0, sizeof(struct cifsFileInfo)); | |
47 | private_data->netfid = netfid; | |
48 | private_data->pid = current->tgid; | |
49 | init_MUTEX(&private_data->fh_sem); | |
50 | mutex_init(&private_data->lock_mutex); | |
51 | INIT_LIST_HEAD(&private_data->llist); | |
52 | private_data->pfile = file; /* needed for writepage */ | |
53 | private_data->pInode = inode; | |
54 | private_data->invalidHandle = FALSE; | |
55 | private_data->closePend = FALSE; | |
56 | /* we have to track num writers to the inode, since writepages | |
57 | does not tell us which handle the write is for so there can | |
58 | be a close (overlapping with write) of the filehandle that | |
59 | cifs_writepages chose to use */ | |
60 | atomic_set(&private_data->wrtPending, 0); | |
61 | ||
62 | return private_data; | |
63 | } | |
64 | ||
65 | static inline int cifs_convert_flags(unsigned int flags) | |
66 | { | |
67 | if ((flags & O_ACCMODE) == O_RDONLY) | |
68 | return GENERIC_READ; | |
69 | else if ((flags & O_ACCMODE) == O_WRONLY) | |
70 | return GENERIC_WRITE; | |
71 | else if ((flags & O_ACCMODE) == O_RDWR) { | |
72 | /* GENERIC_ALL is too much permission to request | |
73 | can cause unnecessary access denied on create */ | |
74 | /* return GENERIC_ALL; */ | |
75 | return (GENERIC_READ | GENERIC_WRITE); | |
76 | } | |
77 | ||
78 | return 0x20197; | |
79 | } | |
80 | ||
81 | static inline int cifs_get_disposition(unsigned int flags) | |
82 | { | |
83 | if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) | |
84 | return FILE_CREATE; | |
85 | else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC)) | |
86 | return FILE_OVERWRITE_IF; | |
87 | else if ((flags & O_CREAT) == O_CREAT) | |
88 | return FILE_OPEN_IF; | |
89 | else if ((flags & O_TRUNC) == O_TRUNC) | |
90 | return FILE_OVERWRITE; | |
91 | else | |
92 | return FILE_OPEN; | |
93 | } | |
94 | ||
95 | /* all arguments to this function must be checked for validity in caller */ | |
96 | static inline int cifs_open_inode_helper(struct inode *inode, struct file *file, | |
97 | struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile, | |
98 | struct cifsTconInfo *pTcon, int *oplock, FILE_ALL_INFO *buf, | |
99 | char *full_path, int xid) | |
100 | { | |
101 | struct timespec temp; | |
102 | int rc; | |
103 | ||
104 | /* want handles we can use to read with first | |
105 | in the list so we do not have to walk the | |
106 | list to search for one in prepare_write */ | |
107 | if ((file->f_flags & O_ACCMODE) == O_WRONLY) { | |
108 | list_add_tail(&pCifsFile->flist, | |
109 | &pCifsInode->openFileList); | |
110 | } else { | |
111 | list_add(&pCifsFile->flist, | |
112 | &pCifsInode->openFileList); | |
113 | } | |
114 | write_unlock(&GlobalSMBSeslock); | |
115 | if (pCifsInode->clientCanCacheRead) { | |
116 | /* we have the inode open somewhere else | |
117 | no need to discard cache data */ | |
118 | goto client_can_cache; | |
119 | } | |
120 | ||
121 | /* BB need same check in cifs_create too? */ | |
122 | /* if not oplocked, invalidate inode pages if mtime or file | |
123 | size changed */ | |
124 | temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime)); | |
125 | if (timespec_equal(&file->f_path.dentry->d_inode->i_mtime, &temp) && | |
126 | (file->f_path.dentry->d_inode->i_size == | |
127 | (loff_t)le64_to_cpu(buf->EndOfFile))) { | |
128 | cFYI(1, ("inode unchanged on server")); | |
129 | } else { | |
130 | if (file->f_path.dentry->d_inode->i_mapping) { | |
131 | /* BB no need to lock inode until after invalidate | |
132 | since namei code should already have it locked? */ | |
133 | filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping); | |
134 | } | |
135 | cFYI(1, ("invalidating remote inode since open detected it " | |
136 | "changed")); | |
137 | invalidate_remote_inode(file->f_path.dentry->d_inode); | |
138 | } | |
139 | ||
140 | client_can_cache: | |
141 | if (pTcon->unix_ext) | |
142 | rc = cifs_get_inode_info_unix(&file->f_path.dentry->d_inode, | |
143 | full_path, inode->i_sb, xid); | |
144 | else | |
145 | rc = cifs_get_inode_info(&file->f_path.dentry->d_inode, | |
146 | full_path, buf, inode->i_sb, xid); | |
147 | ||
148 | if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) { | |
149 | pCifsInode->clientCanCacheAll = TRUE; | |
150 | pCifsInode->clientCanCacheRead = TRUE; | |
151 | cFYI(1, ("Exclusive Oplock granted on inode %p", | |
152 | file->f_path.dentry->d_inode)); | |
153 | } else if ((*oplock & 0xF) == OPLOCK_READ) | |
154 | pCifsInode->clientCanCacheRead = TRUE; | |
155 | ||
156 | return rc; | |
157 | } | |
158 | ||
159 | int cifs_open(struct inode *inode, struct file *file) | |
160 | { | |
161 | int rc = -EACCES; | |
162 | int xid, oplock; | |
163 | struct cifs_sb_info *cifs_sb; | |
164 | struct cifsTconInfo *pTcon; | |
165 | struct cifsFileInfo *pCifsFile; | |
166 | struct cifsInodeInfo *pCifsInode; | |
167 | struct list_head *tmp; | |
168 | char *full_path = NULL; | |
169 | int desiredAccess; | |
170 | int disposition; | |
171 | __u16 netfid; | |
172 | FILE_ALL_INFO *buf = NULL; | |
173 | ||
174 | xid = GetXid(); | |
175 | ||
176 | cifs_sb = CIFS_SB(inode->i_sb); | |
177 | pTcon = cifs_sb->tcon; | |
178 | ||
179 | if (file->f_flags & O_CREAT) { | |
180 | /* search inode for this file and fill in file->private_data */ | |
181 | pCifsInode = CIFS_I(file->f_path.dentry->d_inode); | |
182 | read_lock(&GlobalSMBSeslock); | |
183 | list_for_each(tmp, &pCifsInode->openFileList) { | |
184 | pCifsFile = list_entry(tmp, struct cifsFileInfo, | |
185 | flist); | |
186 | if ((pCifsFile->pfile == NULL) && | |
187 | (pCifsFile->pid == current->tgid)) { | |
188 | /* mode set in cifs_create */ | |
189 | ||
190 | /* needed for writepage */ | |
191 | pCifsFile->pfile = file; | |
192 | ||
193 | file->private_data = pCifsFile; | |
194 | break; | |
195 | } | |
196 | } | |
197 | read_unlock(&GlobalSMBSeslock); | |
198 | if (file->private_data != NULL) { | |
199 | rc = 0; | |
200 | FreeXid(xid); | |
201 | return rc; | |
202 | } else { | |
203 | if (file->f_flags & O_EXCL) | |
204 | cERROR(1, ("could not find file instance for " | |
205 | "new file %p", file)); | |
206 | } | |
207 | } | |
208 | ||
209 | full_path = build_path_from_dentry(file->f_path.dentry); | |
210 | if (full_path == NULL) { | |
211 | FreeXid(xid); | |
212 | return -ENOMEM; | |
213 | } | |
214 | ||
215 | cFYI(1, ("inode = 0x%p file flags are 0x%x for %s", | |
216 | inode, file->f_flags, full_path)); | |
217 | desiredAccess = cifs_convert_flags(file->f_flags); | |
218 | ||
219 | /********************************************************************* | |
220 | * open flag mapping table: | |
221 | * | |
222 | * POSIX Flag CIFS Disposition | |
223 | * ---------- ---------------- | |
224 | * O_CREAT FILE_OPEN_IF | |
225 | * O_CREAT | O_EXCL FILE_CREATE | |
226 | * O_CREAT | O_TRUNC FILE_OVERWRITE_IF | |
227 | * O_TRUNC FILE_OVERWRITE | |
228 | * none of the above FILE_OPEN | |
229 | * | |
230 | * Note that there is not a direct match between disposition | |
231 | * FILE_SUPERSEDE (ie create whether or not file exists although | |
232 | * O_CREAT | O_TRUNC is similar but truncates the existing | |
233 | * file rather than creating a new file as FILE_SUPERSEDE does | |
234 | * (which uses the attributes / metadata passed in on open call) | |
235 | *? | |
236 | *? O_SYNC is a reasonable match to CIFS writethrough flag | |
237 | *? and the read write flags match reasonably. O_LARGEFILE | |
238 | *? is irrelevant because largefile support is always used | |
239 | *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY, | |
240 | * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation | |
241 | *********************************************************************/ | |
242 | ||
243 | disposition = cifs_get_disposition(file->f_flags); | |
244 | ||
245 | if (oplockEnabled) | |
246 | oplock = REQ_OPLOCK; | |
247 | else | |
248 | oplock = FALSE; | |
249 | ||
250 | /* BB pass O_SYNC flag through on file attributes .. BB */ | |
251 | ||
252 | /* Also refresh inode by passing in file_info buf returned by SMBOpen | |
253 | and calling get_inode_info with returned buf (at least helps | |
254 | non-Unix server case) */ | |
255 | ||
256 | /* BB we can not do this if this is the second open of a file | |
257 | and the first handle has writebehind data, we might be | |
258 | able to simply do a filemap_fdatawrite/filemap_fdatawait first */ | |
259 | buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL); | |
260 | if (!buf) { | |
261 | rc = -ENOMEM; | |
262 | goto out; | |
263 | } | |
264 | ||
265 | if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS) | |
266 | rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, | |
267 | desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf, | |
268 | cifs_sb->local_nls, cifs_sb->mnt_cifs_flags | |
269 | & CIFS_MOUNT_MAP_SPECIAL_CHR); | |
270 | else | |
271 | rc = -EIO; /* no NT SMB support fall into legacy open below */ | |
272 | ||
273 | if (rc == -EIO) { | |
274 | /* Old server, try legacy style OpenX */ | |
275 | rc = SMBLegacyOpen(xid, pTcon, full_path, disposition, | |
276 | desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf, | |
277 | cifs_sb->local_nls, cifs_sb->mnt_cifs_flags | |
278 | & CIFS_MOUNT_MAP_SPECIAL_CHR); | |
279 | } | |
280 | if (rc) { | |
281 | cFYI(1, ("cifs_open returned 0x%x", rc)); | |
282 | goto out; | |
283 | } | |
284 | file->private_data = | |
285 | kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); | |
286 | if (file->private_data == NULL) { | |
287 | rc = -ENOMEM; | |
288 | goto out; | |
289 | } | |
290 | pCifsFile = cifs_init_private(file->private_data, inode, file, netfid); | |
291 | write_lock(&GlobalSMBSeslock); | |
292 | list_add(&pCifsFile->tlist, &pTcon->openFileList); | |
293 | ||
294 | pCifsInode = CIFS_I(file->f_path.dentry->d_inode); | |
295 | if (pCifsInode) { | |
296 | rc = cifs_open_inode_helper(inode, file, pCifsInode, | |
297 | pCifsFile, pTcon, | |
298 | &oplock, buf, full_path, xid); | |
299 | } else { | |
300 | write_unlock(&GlobalSMBSeslock); | |
301 | } | |
302 | ||
303 | if (oplock & CIFS_CREATE_ACTION) { | |
304 | /* time to set mode which we can not set earlier due to | |
305 | problems creating new read-only files */ | |
306 | if (pTcon->unix_ext) { | |
307 | CIFSSMBUnixSetPerms(xid, pTcon, full_path, | |
308 | inode->i_mode, | |
309 | (__u64)-1, (__u64)-1, 0 /* dev */, | |
310 | cifs_sb->local_nls, | |
311 | cifs_sb->mnt_cifs_flags & | |
312 | CIFS_MOUNT_MAP_SPECIAL_CHR); | |
313 | } else { | |
314 | /* BB implement via Windows security descriptors eg | |
315 | CIFSSMBWinSetPerms(xid, pTcon, full_path, mode, | |
316 | -1, -1, local_nls); | |
317 | in the meantime could set r/o dos attribute when | |
318 | perms are eg: mode & 0222 == 0 */ | |
319 | } | |
320 | } | |
321 | ||
322 | out: | |
323 | kfree(buf); | |
324 | kfree(full_path); | |
325 | FreeXid(xid); | |
326 | return rc; | |
327 | } | |
328 | ||
329 | /* Try to reacquire byte range locks that were released when session */ | |
330 | /* to server was lost */ | |
331 | static int cifs_relock_file(struct cifsFileInfo *cifsFile) | |
332 | { | |
333 | int rc = 0; | |
334 | ||
335 | /* BB list all locks open on this file and relock */ | |
336 | ||
337 | return rc; | |
338 | } | |
339 | ||
340 | static int cifs_reopen_file(struct file *file, int can_flush) | |
341 | { | |
342 | int rc = -EACCES; | |
343 | int xid, oplock; | |
344 | struct cifs_sb_info *cifs_sb; | |
345 | struct cifsTconInfo *pTcon; | |
346 | struct cifsFileInfo *pCifsFile; | |
347 | struct cifsInodeInfo *pCifsInode; | |
348 | struct inode *inode; | |
349 | char *full_path = NULL; | |
350 | int desiredAccess; | |
351 | int disposition = FILE_OPEN; | |
352 | __u16 netfid; | |
353 | ||
354 | if (file->private_data) { | |
355 | pCifsFile = (struct cifsFileInfo *)file->private_data; | |
356 | } else | |
357 | return -EBADF; | |
358 | ||
359 | xid = GetXid(); | |
360 | down(&pCifsFile->fh_sem); | |
361 | if (pCifsFile->invalidHandle == FALSE) { | |
362 | up(&pCifsFile->fh_sem); | |
363 | FreeXid(xid); | |
364 | return 0; | |
365 | } | |
366 | ||
367 | if (file->f_path.dentry == NULL) { | |
368 | cERROR(1, ("no valid name if dentry freed")); | |
369 | dump_stack(); | |
370 | rc = -EBADF; | |
371 | goto reopen_error_exit; | |
372 | } | |
373 | ||
374 | inode = file->f_path.dentry->d_inode; | |
375 | if (inode == NULL) { | |
376 | cERROR(1, ("inode not valid")); | |
377 | dump_stack(); | |
378 | rc = -EBADF; | |
379 | goto reopen_error_exit; | |
380 | } | |
381 | ||
382 | cifs_sb = CIFS_SB(inode->i_sb); | |
383 | pTcon = cifs_sb->tcon; | |
384 | ||
385 | /* can not grab rename sem here because various ops, including | |
386 | those that already have the rename sem can end up causing writepage | |
387 | to get called and if the server was down that means we end up here, | |
388 | and we can never tell if the caller already has the rename_sem */ | |
389 | full_path = build_path_from_dentry(file->f_path.dentry); | |
390 | if (full_path == NULL) { | |
391 | rc = -ENOMEM; | |
392 | reopen_error_exit: | |
393 | up(&pCifsFile->fh_sem); | |
394 | FreeXid(xid); | |
395 | return rc; | |
396 | } | |
397 | ||
398 | cFYI(1, ("inode = 0x%p file flags 0x%x for %s", | |
399 | inode, file->f_flags, full_path)); | |
400 | desiredAccess = cifs_convert_flags(file->f_flags); | |
401 | ||
402 | if (oplockEnabled) | |
403 | oplock = REQ_OPLOCK; | |
404 | else | |
405 | oplock = FALSE; | |
406 | ||
407 | /* Can not refresh inode by passing in file_info buf to be returned | |
408 | by SMBOpen and then calling get_inode_info with returned buf | |
409 | since file might have write behind data that needs to be flushed | |
410 | and server version of file size can be stale. If we knew for sure | |
411 | that inode was not dirty locally we could do this */ | |
412 | ||
413 | rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess, | |
414 | CREATE_NOT_DIR, &netfid, &oplock, NULL, | |
415 | cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & | |
416 | CIFS_MOUNT_MAP_SPECIAL_CHR); | |
417 | if (rc) { | |
418 | up(&pCifsFile->fh_sem); | |
419 | cFYI(1, ("cifs_open returned 0x%x", rc)); | |
420 | cFYI(1, ("oplock: %d", oplock)); | |
421 | } else { | |
422 | pCifsFile->netfid = netfid; | |
423 | pCifsFile->invalidHandle = FALSE; | |
424 | up(&pCifsFile->fh_sem); | |
425 | pCifsInode = CIFS_I(inode); | |
426 | if (pCifsInode) { | |
427 | if (can_flush) { | |
428 | filemap_write_and_wait(inode->i_mapping); | |
429 | /* temporarily disable caching while we | |
430 | go to server to get inode info */ | |
431 | pCifsInode->clientCanCacheAll = FALSE; | |
432 | pCifsInode->clientCanCacheRead = FALSE; | |
433 | if (pTcon->unix_ext) | |
434 | rc = cifs_get_inode_info_unix(&inode, | |
435 | full_path, inode->i_sb, xid); | |
436 | else | |
437 | rc = cifs_get_inode_info(&inode, | |
438 | full_path, NULL, inode->i_sb, | |
439 | xid); | |
440 | } /* else we are writing out data to server already | |
441 | and could deadlock if we tried to flush data, and | |
442 | since we do not know if we have data that would | |
443 | invalidate the current end of file on the server | |
444 | we can not go to the server to get the new inod | |
445 | info */ | |
446 | if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) { | |
447 | pCifsInode->clientCanCacheAll = TRUE; | |
448 | pCifsInode->clientCanCacheRead = TRUE; | |
449 | cFYI(1, ("Exclusive Oplock granted on inode %p", | |
450 | file->f_path.dentry->d_inode)); | |
451 | } else if ((oplock & 0xF) == OPLOCK_READ) { | |
452 | pCifsInode->clientCanCacheRead = TRUE; | |
453 | pCifsInode->clientCanCacheAll = FALSE; | |
454 | } else { | |
455 | pCifsInode->clientCanCacheRead = FALSE; | |
456 | pCifsInode->clientCanCacheAll = FALSE; | |
457 | } | |
458 | cifs_relock_file(pCifsFile); | |
459 | } | |
460 | } | |
461 | ||
462 | kfree(full_path); | |
463 | FreeXid(xid); | |
464 | return rc; | |
465 | } | |
466 | ||
467 | int cifs_close(struct inode *inode, struct file *file) | |
468 | { | |
469 | int rc = 0; | |
470 | int xid, timeout; | |
471 | struct cifs_sb_info *cifs_sb; | |
472 | struct cifsTconInfo *pTcon; | |
473 | struct cifsFileInfo *pSMBFile = | |
474 | (struct cifsFileInfo *)file->private_data; | |
475 | ||
476 | xid = GetXid(); | |
477 | ||
478 | cifs_sb = CIFS_SB(inode->i_sb); | |
479 | pTcon = cifs_sb->tcon; | |
480 | if (pSMBFile) { | |
481 | struct cifsLockInfo *li, *tmp; | |
482 | ||
483 | pSMBFile->closePend = TRUE; | |
484 | if (pTcon) { | |
485 | /* no sense reconnecting to close a file that is | |
486 | already closed */ | |
487 | if (pTcon->tidStatus != CifsNeedReconnect) { | |
488 | timeout = 2; | |
489 | while ((atomic_read(&pSMBFile->wrtPending) != 0) | |
490 | && (timeout <= 2048)) { | |
491 | /* Give write a better chance to get to | |
492 | server ahead of the close. We do not | |
493 | want to add a wait_q here as it would | |
494 | increase the memory utilization as | |
495 | the struct would be in each open file, | |
496 | but this should give enough time to | |
497 | clear the socket */ | |
498 | #ifdef CONFIG_CIFS_DEBUG2 | |
499 | cFYI(1, ("close delay, write pending")); | |
500 | #endif /* DEBUG2 */ | |
501 | msleep(timeout); | |
502 | timeout *= 4; | |
503 | } | |
504 | if (atomic_read(&pSMBFile->wrtPending)) | |
505 | cERROR(1, | |
506 | ("close with pending writes")); | |
507 | rc = CIFSSMBClose(xid, pTcon, | |
508 | pSMBFile->netfid); | |
509 | } | |
510 | } | |
511 | ||
512 | /* Delete any outstanding lock records. | |
513 | We'll lose them when the file is closed anyway. */ | |
514 | mutex_lock(&pSMBFile->lock_mutex); | |
515 | list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) { | |
516 | list_del(&li->llist); | |
517 | kfree(li); | |
518 | } | |
519 | mutex_unlock(&pSMBFile->lock_mutex); | |
520 | ||
521 | write_lock(&GlobalSMBSeslock); | |
522 | list_del(&pSMBFile->flist); | |
523 | list_del(&pSMBFile->tlist); | |
524 | write_unlock(&GlobalSMBSeslock); | |
525 | timeout = 10; | |
526 | /* We waited above to give the SMBWrite a chance to issue | |
527 | on the wire (so we do not get SMBWrite returning EBADF | |
528 | if writepages is racing with close. Note that writepages | |
529 | does not specify a file handle, so it is possible for a file | |
530 | to be opened twice, and the application close the "wrong" | |
531 | file handle - in these cases we delay long enough to allow | |
532 | the SMBWrite to get on the wire before the SMB Close. | |
533 | We allow total wait here over 45 seconds, more than | |
534 | oplock break time, and more than enough to allow any write | |
535 | to complete on the server, or to time out on the client */ | |
536 | while ((atomic_read(&pSMBFile->wrtPending) != 0) | |
537 | && (timeout <= 50000)) { | |
538 | cERROR(1, ("writes pending, delay free of handle")); | |
539 | msleep(timeout); | |
540 | timeout *= 8; | |
541 | } | |
542 | kfree(pSMBFile->search_resume_name); | |
543 | kfree(file->private_data); | |
544 | file->private_data = NULL; | |
545 | } else | |
546 | rc = -EBADF; | |
547 | ||
548 | read_lock(&GlobalSMBSeslock); | |
549 | if (list_empty(&(CIFS_I(inode)->openFileList))) { | |
550 | cFYI(1, ("closing last open instance for inode %p", inode)); | |
551 | /* if the file is not open we do not know if we can cache info | |
552 | on this inode, much less write behind and read ahead */ | |
553 | CIFS_I(inode)->clientCanCacheRead = FALSE; | |
554 | CIFS_I(inode)->clientCanCacheAll = FALSE; | |
555 | } | |
556 | read_unlock(&GlobalSMBSeslock); | |
557 | if ((rc == 0) && CIFS_I(inode)->write_behind_rc) | |
558 | rc = CIFS_I(inode)->write_behind_rc; | |
559 | FreeXid(xid); | |
560 | return rc; | |
561 | } | |
562 | ||
563 | int cifs_closedir(struct inode *inode, struct file *file) | |
564 | { | |
565 | int rc = 0; | |
566 | int xid; | |
567 | struct cifsFileInfo *pCFileStruct = | |
568 | (struct cifsFileInfo *)file->private_data; | |
569 | char *ptmp; | |
570 | ||
571 | cFYI(1, ("Closedir inode = 0x%p", inode)); | |
572 | ||
573 | xid = GetXid(); | |
574 | ||
575 | if (pCFileStruct) { | |
576 | struct cifsTconInfo *pTcon; | |
577 | struct cifs_sb_info *cifs_sb = | |
578 | CIFS_SB(file->f_path.dentry->d_sb); | |
579 | ||
580 | pTcon = cifs_sb->tcon; | |
581 | ||
582 | cFYI(1, ("Freeing private data in close dir")); | |
583 | if ((pCFileStruct->srch_inf.endOfSearch == FALSE) && | |
584 | (pCFileStruct->invalidHandle == FALSE)) { | |
585 | pCFileStruct->invalidHandle = TRUE; | |
586 | rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid); | |
587 | cFYI(1, ("Closing uncompleted readdir with rc %d", | |
588 | rc)); | |
589 | /* not much we can do if it fails anyway, ignore rc */ | |
590 | rc = 0; | |
591 | } | |
592 | ptmp = pCFileStruct->srch_inf.ntwrk_buf_start; | |
593 | if (ptmp) { | |
594 | cFYI(1, ("closedir free smb buf in srch struct")); | |
595 | pCFileStruct->srch_inf.ntwrk_buf_start = NULL; | |
596 | if (pCFileStruct->srch_inf.smallBuf) | |
597 | cifs_small_buf_release(ptmp); | |
598 | else | |
599 | cifs_buf_release(ptmp); | |
600 | } | |
601 | ptmp = pCFileStruct->search_resume_name; | |
602 | if (ptmp) { | |
603 | cFYI(1, ("closedir free resume name")); | |
604 | pCFileStruct->search_resume_name = NULL; | |
605 | kfree(ptmp); | |
606 | } | |
607 | kfree(file->private_data); | |
608 | file->private_data = NULL; | |
609 | } | |
610 | /* BB can we lock the filestruct while this is going on? */ | |
611 | FreeXid(xid); | |
612 | return rc; | |
613 | } | |
614 | ||
615 | static int store_file_lock(struct cifsFileInfo *fid, __u64 len, | |
616 | __u64 offset, __u8 lockType) | |
617 | { | |
618 | struct cifsLockInfo *li = | |
619 | kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL); | |
620 | if (li == NULL) | |
621 | return -ENOMEM; | |
622 | li->offset = offset; | |
623 | li->length = len; | |
624 | li->type = lockType; | |
625 | mutex_lock(&fid->lock_mutex); | |
626 | list_add(&li->llist, &fid->llist); | |
627 | mutex_unlock(&fid->lock_mutex); | |
628 | return 0; | |
629 | } | |
630 | ||
631 | int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock) | |
632 | { | |
633 | int rc, xid; | |
634 | __u32 numLock = 0; | |
635 | __u32 numUnlock = 0; | |
636 | __u64 length; | |
637 | int wait_flag = FALSE; | |
638 | struct cifs_sb_info *cifs_sb; | |
639 | struct cifsTconInfo *pTcon; | |
640 | __u16 netfid; | |
641 | __u8 lockType = LOCKING_ANDX_LARGE_FILES; | |
642 | int posix_locking; | |
643 | ||
644 | length = 1 + pfLock->fl_end - pfLock->fl_start; | |
645 | rc = -EACCES; | |
646 | xid = GetXid(); | |
647 | ||
648 | cFYI(1, ("Lock parm: 0x%x flockflags: " | |
649 | "0x%x flocktype: 0x%x start: %lld end: %lld", | |
650 | cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start, | |
651 | pfLock->fl_end)); | |
652 | ||
653 | if (pfLock->fl_flags & FL_POSIX) | |
654 | cFYI(1, ("Posix")); | |
655 | if (pfLock->fl_flags & FL_FLOCK) | |
656 | cFYI(1, ("Flock")); | |
657 | if (pfLock->fl_flags & FL_SLEEP) { | |
658 | cFYI(1, ("Blocking lock")); | |
659 | wait_flag = TRUE; | |
660 | } | |
661 | if (pfLock->fl_flags & FL_ACCESS) | |
662 | cFYI(1, ("Process suspended by mandatory locking - " | |
663 | "not implemented yet")); | |
664 | if (pfLock->fl_flags & FL_LEASE) | |
665 | cFYI(1, ("Lease on file - not implemented yet")); | |
666 | if (pfLock->fl_flags & | |
667 | (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE))) | |
668 | cFYI(1, ("Unknown lock flags 0x%x", pfLock->fl_flags)); | |
669 | ||
670 | if (pfLock->fl_type == F_WRLCK) { | |
671 | cFYI(1, ("F_WRLCK ")); | |
672 | numLock = 1; | |
673 | } else if (pfLock->fl_type == F_UNLCK) { | |
674 | cFYI(1, ("F_UNLCK")); | |
675 | numUnlock = 1; | |
676 | /* Check if unlock includes more than | |
677 | one lock range */ | |
678 | } else if (pfLock->fl_type == F_RDLCK) { | |
679 | cFYI(1, ("F_RDLCK")); | |
680 | lockType |= LOCKING_ANDX_SHARED_LOCK; | |
681 | numLock = 1; | |
682 | } else if (pfLock->fl_type == F_EXLCK) { | |
683 | cFYI(1, ("F_EXLCK")); | |
684 | numLock = 1; | |
685 | } else if (pfLock->fl_type == F_SHLCK) { | |
686 | cFYI(1, ("F_SHLCK")); | |
687 | lockType |= LOCKING_ANDX_SHARED_LOCK; | |
688 | numLock = 1; | |
689 | } else | |
690 | cFYI(1, ("Unknown type of lock")); | |
691 | ||
692 | cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); | |
693 | pTcon = cifs_sb->tcon; | |
694 | ||
695 | if (file->private_data == NULL) { | |
696 | FreeXid(xid); | |
697 | return -EBADF; | |
698 | } | |
699 | netfid = ((struct cifsFileInfo *)file->private_data)->netfid; | |
700 | ||
701 | posix_locking = (cifs_sb->tcon->ses->capabilities & CAP_UNIX) && | |
702 | (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability)); | |
703 | ||
704 | /* BB add code here to normalize offset and length to | |
705 | account for negative length which we can not accept over the | |
706 | wire */ | |
707 | if (IS_GETLK(cmd)) { | |
708 | if (posix_locking) { | |
709 | int posix_lock_type; | |
710 | if (lockType & LOCKING_ANDX_SHARED_LOCK) | |
711 | posix_lock_type = CIFS_RDLCK; | |
712 | else | |
713 | posix_lock_type = CIFS_WRLCK; | |
714 | rc = CIFSSMBPosixLock(xid, pTcon, netfid, 1 /* get */, | |
715 | length, pfLock, | |
716 | posix_lock_type, wait_flag); | |
717 | FreeXid(xid); | |
718 | return rc; | |
719 | } | |
720 | ||
721 | /* BB we could chain these into one lock request BB */ | |
722 | rc = CIFSSMBLock(xid, pTcon, netfid, length, pfLock->fl_start, | |
723 | 0, 1, lockType, 0 /* wait flag */ ); | |
724 | if (rc == 0) { | |
725 | rc = CIFSSMBLock(xid, pTcon, netfid, length, | |
726 | pfLock->fl_start, 1 /* numUnlock */ , | |
727 | 0 /* numLock */ , lockType, | |
728 | 0 /* wait flag */ ); | |
729 | pfLock->fl_type = F_UNLCK; | |
730 | if (rc != 0) | |
731 | cERROR(1, ("Error unlocking previously locked " | |
732 | "range %d during test of lock", rc)); | |
733 | rc = 0; | |
734 | ||
735 | } else { | |
736 | /* if rc == ERR_SHARING_VIOLATION ? */ | |
737 | rc = 0; /* do not change lock type to unlock | |
738 | since range in use */ | |
739 | } | |
740 | ||
741 | FreeXid(xid); | |
742 | return rc; | |
743 | } | |
744 | ||
745 | if (!numLock && !numUnlock) { | |
746 | /* if no lock or unlock then nothing | |
747 | to do since we do not know what it is */ | |
748 | FreeXid(xid); | |
749 | return -EOPNOTSUPP; | |
750 | } | |
751 | ||
752 | if (posix_locking) { | |
753 | int posix_lock_type; | |
754 | if (lockType & LOCKING_ANDX_SHARED_LOCK) | |
755 | posix_lock_type = CIFS_RDLCK; | |
756 | else | |
757 | posix_lock_type = CIFS_WRLCK; | |
758 | ||
759 | if (numUnlock == 1) | |
760 | posix_lock_type = CIFS_UNLCK; | |
761 | ||
762 | rc = CIFSSMBPosixLock(xid, pTcon, netfid, 0 /* set */, | |
763 | length, pfLock, | |
764 | posix_lock_type, wait_flag); | |
765 | } else { | |
766 | struct cifsFileInfo *fid = | |
767 | (struct cifsFileInfo *)file->private_data; | |
768 | ||
769 | if (numLock) { | |
770 | rc = CIFSSMBLock(xid, pTcon, netfid, length, | |
771 | pfLock->fl_start, | |
772 | 0, numLock, lockType, wait_flag); | |
773 | ||
774 | if (rc == 0) { | |
775 | /* For Windows locks we must store them. */ | |
776 | rc = store_file_lock(fid, length, | |
777 | pfLock->fl_start, lockType); | |
778 | } | |
779 | } else if (numUnlock) { | |
780 | /* For each stored lock that this unlock overlaps | |
781 | completely, unlock it. */ | |
782 | int stored_rc = 0; | |
783 | struct cifsLockInfo *li, *tmp; | |
784 | ||
785 | rc = 0; | |
786 | mutex_lock(&fid->lock_mutex); | |
787 | list_for_each_entry_safe(li, tmp, &fid->llist, llist) { | |
788 | if (pfLock->fl_start <= li->offset && | |
789 | (pfLock->fl_start + length) >= | |
790 | (li->offset + li->length)) { | |
791 | stored_rc = CIFSSMBLock(xid, pTcon, | |
792 | netfid, | |
793 | li->length, li->offset, | |
794 | 1, 0, li->type, FALSE); | |
795 | if (stored_rc) | |
796 | rc = stored_rc; | |
797 | ||
798 | list_del(&li->llist); | |
799 | kfree(li); | |
800 | } | |
801 | } | |
802 | mutex_unlock(&fid->lock_mutex); | |
803 | } | |
804 | } | |
805 | ||
806 | if (pfLock->fl_flags & FL_POSIX) | |
807 | posix_lock_file_wait(file, pfLock); | |
808 | FreeXid(xid); | |
809 | return rc; | |
810 | } | |
811 | ||
812 | ssize_t cifs_user_write(struct file *file, const char __user *write_data, | |
813 | size_t write_size, loff_t *poffset) | |
814 | { | |
815 | int rc = 0; | |
816 | unsigned int bytes_written = 0; | |
817 | unsigned int total_written; | |
818 | struct cifs_sb_info *cifs_sb; | |
819 | struct cifsTconInfo *pTcon; | |
820 | int xid, long_op; | |
821 | struct cifsFileInfo *open_file; | |
822 | ||
823 | cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); | |
824 | ||
825 | pTcon = cifs_sb->tcon; | |
826 | ||
827 | /* cFYI(1, | |
828 | (" write %d bytes to offset %lld of %s", write_size, | |
829 | *poffset, file->f_path.dentry->d_name.name)); */ | |
830 | ||
831 | if (file->private_data == NULL) | |
832 | return -EBADF; | |
833 | open_file = (struct cifsFileInfo *) file->private_data; | |
834 | ||
835 | xid = GetXid(); | |
836 | ||
837 | if (*poffset > file->f_path.dentry->d_inode->i_size) | |
838 | long_op = CIFS_VLONG_OP; /* writes past EOF take long time */ | |
839 | else | |
840 | long_op = CIFS_LONG_OP; | |
841 | ||
842 | for (total_written = 0; write_size > total_written; | |
843 | total_written += bytes_written) { | |
844 | rc = -EAGAIN; | |
845 | while (rc == -EAGAIN) { | |
846 | if (file->private_data == NULL) { | |
847 | /* file has been closed on us */ | |
848 | FreeXid(xid); | |
849 | /* if we have gotten here we have written some data | |
850 | and blocked, and the file has been freed on us while | |
851 | we blocked so return what we managed to write */ | |
852 | return total_written; | |
853 | } | |
854 | if (open_file->closePend) { | |
855 | FreeXid(xid); | |
856 | if (total_written) | |
857 | return total_written; | |
858 | else | |
859 | return -EBADF; | |
860 | } | |
861 | if (open_file->invalidHandle) { | |
862 | /* we could deadlock if we called | |
863 | filemap_fdatawait from here so tell | |
864 | reopen_file not to flush data to server | |
865 | now */ | |
866 | rc = cifs_reopen_file(file, FALSE); | |
867 | if (rc != 0) | |
868 | break; | |
869 | } | |
870 | ||
871 | rc = CIFSSMBWrite(xid, pTcon, | |
872 | open_file->netfid, | |
873 | min_t(const int, cifs_sb->wsize, | |
874 | write_size - total_written), | |
875 | *poffset, &bytes_written, | |
876 | NULL, write_data + total_written, long_op); | |
877 | } | |
878 | if (rc || (bytes_written == 0)) { | |
879 | if (total_written) | |
880 | break; | |
881 | else { | |
882 | FreeXid(xid); | |
883 | return rc; | |
884 | } | |
885 | } else | |
886 | *poffset += bytes_written; | |
887 | long_op = CIFS_STD_OP; /* subsequent writes fast - | |
888 | 15 seconds is plenty */ | |
889 | } | |
890 | ||
891 | cifs_stats_bytes_written(pTcon, total_written); | |
892 | ||
893 | /* since the write may have blocked check these pointers again */ | |
894 | if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) { | |
895 | struct inode *inode = file->f_path.dentry->d_inode; | |
896 | /* Do not update local mtime - server will set its actual value on write | |
897 | * inode->i_ctime = inode->i_mtime = | |
898 | * current_fs_time(inode->i_sb);*/ | |
899 | if (total_written > 0) { | |
900 | spin_lock(&inode->i_lock); | |
901 | if (*poffset > file->f_path.dentry->d_inode->i_size) | |
902 | i_size_write(file->f_path.dentry->d_inode, | |
903 | *poffset); | |
904 | spin_unlock(&inode->i_lock); | |
905 | } | |
906 | mark_inode_dirty_sync(file->f_path.dentry->d_inode); | |
907 | } | |
908 | FreeXid(xid); | |
909 | return total_written; | |
910 | } | |
911 | ||
912 | static ssize_t cifs_write(struct file *file, const char *write_data, | |
913 | size_t write_size, loff_t *poffset) | |
914 | { | |
915 | int rc = 0; | |
916 | unsigned int bytes_written = 0; | |
917 | unsigned int total_written; | |
918 | struct cifs_sb_info *cifs_sb; | |
919 | struct cifsTconInfo *pTcon; | |
920 | int xid, long_op; | |
921 | struct cifsFileInfo *open_file; | |
922 | ||
923 | cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); | |
924 | ||
925 | pTcon = cifs_sb->tcon; | |
926 | ||
927 | cFYI(1, ("write %zd bytes to offset %lld of %s", write_size, | |
928 | *poffset, file->f_path.dentry->d_name.name)); | |
929 | ||
930 | if (file->private_data == NULL) | |
931 | return -EBADF; | |
932 | open_file = (struct cifsFileInfo *)file->private_data; | |
933 | ||
934 | xid = GetXid(); | |
935 | ||
936 | if (*poffset > file->f_path.dentry->d_inode->i_size) | |
937 | long_op = CIFS_VLONG_OP; /* writes past EOF can be slow */ | |
938 | else | |
939 | long_op = CIFS_LONG_OP; | |
940 | ||
941 | for (total_written = 0; write_size > total_written; | |
942 | total_written += bytes_written) { | |
943 | rc = -EAGAIN; | |
944 | while (rc == -EAGAIN) { | |
945 | if (file->private_data == NULL) { | |
946 | /* file has been closed on us */ | |
947 | FreeXid(xid); | |
948 | /* if we have gotten here we have written some data | |
949 | and blocked, and the file has been freed on us | |
950 | while we blocked so return what we managed to | |
951 | write */ | |
952 | return total_written; | |
953 | } | |
954 | if (open_file->closePend) { | |
955 | FreeXid(xid); | |
956 | if (total_written) | |
957 | return total_written; | |
958 | else | |
959 | return -EBADF; | |
960 | } | |
961 | if (open_file->invalidHandle) { | |
962 | /* we could deadlock if we called | |
963 | filemap_fdatawait from here so tell | |
964 | reopen_file not to flush data to | |
965 | server now */ | |
966 | rc = cifs_reopen_file(file, FALSE); | |
967 | if (rc != 0) | |
968 | break; | |
969 | } | |
970 | if (experimEnabled || (pTcon->ses->server && | |
971 | ((pTcon->ses->server->secMode & | |
972 | (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) | |
973 | == 0))) { | |
974 | struct kvec iov[2]; | |
975 | unsigned int len; | |
976 | ||
977 | len = min((size_t)cifs_sb->wsize, | |
978 | write_size - total_written); | |
979 | /* iov[0] is reserved for smb header */ | |
980 | iov[1].iov_base = (char *)write_data + | |
981 | total_written; | |
982 | iov[1].iov_len = len; | |
983 | rc = CIFSSMBWrite2(xid, pTcon, | |
984 | open_file->netfid, len, | |
985 | *poffset, &bytes_written, | |
986 | iov, 1, long_op); | |
987 | } else | |
988 | rc = CIFSSMBWrite(xid, pTcon, | |
989 | open_file->netfid, | |
990 | min_t(const int, cifs_sb->wsize, | |
991 | write_size - total_written), | |
992 | *poffset, &bytes_written, | |
993 | write_data + total_written, | |
994 | NULL, long_op); | |
995 | } | |
996 | if (rc || (bytes_written == 0)) { | |
997 | if (total_written) | |
998 | break; | |
999 | else { | |
1000 | FreeXid(xid); | |
1001 | return rc; | |
1002 | } | |
1003 | } else | |
1004 | *poffset += bytes_written; | |
1005 | long_op = CIFS_STD_OP; /* subsequent writes fast - | |
1006 | 15 seconds is plenty */ | |
1007 | } | |
1008 | ||
1009 | cifs_stats_bytes_written(pTcon, total_written); | |
1010 | ||
1011 | /* since the write may have blocked check these pointers again */ | |
1012 | if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) { | |
1013 | /*BB We could make this contingent on superblock ATIME flag too */ | |
1014 | /* file->f_path.dentry->d_inode->i_ctime = | |
1015 | file->f_path.dentry->d_inode->i_mtime = CURRENT_TIME;*/ | |
1016 | if (total_written > 0) { | |
1017 | spin_lock(&file->f_path.dentry->d_inode->i_lock); | |
1018 | if (*poffset > file->f_path.dentry->d_inode->i_size) | |
1019 | i_size_write(file->f_path.dentry->d_inode, | |
1020 | *poffset); | |
1021 | spin_unlock(&file->f_path.dentry->d_inode->i_lock); | |
1022 | } | |
1023 | mark_inode_dirty_sync(file->f_path.dentry->d_inode); | |
1024 | } | |
1025 | FreeXid(xid); | |
1026 | return total_written; | |
1027 | } | |
1028 | ||
1029 | #ifdef CONFIG_CIFS_EXPERIMENTAL | |
1030 | struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode) | |
1031 | { | |
1032 | struct cifsFileInfo *open_file = NULL; | |
1033 | ||
1034 | read_lock(&GlobalSMBSeslock); | |
1035 | /* we could simply get the first_list_entry since write-only entries | |
1036 | are always at the end of the list but since the first entry might | |
1037 | have a close pending, we go through the whole list */ | |
1038 | list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { | |
1039 | if (open_file->closePend) | |
1040 | continue; | |
1041 | if (open_file->pfile && ((open_file->pfile->f_flags & O_RDWR) || | |
1042 | (open_file->pfile->f_flags & O_RDONLY))) { | |
1043 | if (!open_file->invalidHandle) { | |
1044 | /* found a good file */ | |
1045 | /* lock it so it will not be closed on us */ | |
1046 | atomic_inc(&open_file->wrtPending); | |
1047 | read_unlock(&GlobalSMBSeslock); | |
1048 | return open_file; | |
1049 | } /* else might as well continue, and look for | |
1050 | another, or simply have the caller reopen it | |
1051 | again rather than trying to fix this handle */ | |
1052 | } else /* write only file */ | |
1053 | break; /* write only files are last so must be done */ | |
1054 | } | |
1055 | read_unlock(&GlobalSMBSeslock); | |
1056 | return NULL; | |
1057 | } | |
1058 | #endif | |
1059 | ||
1060 | struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode) | |
1061 | { | |
1062 | struct cifsFileInfo *open_file; | |
1063 | int rc; | |
1064 | ||
1065 | /* Having a null inode here (because mapping->host was set to zero by | |
1066 | the VFS or MM) should not happen but we had reports of on oops (due to | |
1067 | it being zero) during stress testcases so we need to check for it */ | |
1068 | ||
1069 | if (cifs_inode == NULL) { | |
1070 | cERROR(1, ("Null inode passed to cifs_writeable_file")); | |
1071 | dump_stack(); | |
1072 | return NULL; | |
1073 | } | |
1074 | ||
1075 | read_lock(&GlobalSMBSeslock); | |
1076 | refind_writable: | |
1077 | list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { | |
1078 | if (open_file->closePend) | |
1079 | continue; | |
1080 | if (open_file->pfile && | |
1081 | ((open_file->pfile->f_flags & O_RDWR) || | |
1082 | (open_file->pfile->f_flags & O_WRONLY))) { | |
1083 | atomic_inc(&open_file->wrtPending); | |
1084 | ||
1085 | if (!open_file->invalidHandle) { | |
1086 | /* found a good writable file */ | |
1087 | read_unlock(&GlobalSMBSeslock); | |
1088 | return open_file; | |
1089 | } | |
1090 | ||
1091 | read_unlock(&GlobalSMBSeslock); | |
1092 | /* Had to unlock since following call can block */ | |
1093 | rc = cifs_reopen_file(open_file->pfile, FALSE); | |
1094 | if (!rc) { | |
1095 | if (!open_file->closePend) | |
1096 | return open_file; | |
1097 | else { /* start over in case this was deleted */ | |
1098 | /* since the list could be modified */ | |
1099 | read_lock(&GlobalSMBSeslock); | |
1100 | atomic_dec(&open_file->wrtPending); | |
1101 | goto refind_writable; | |
1102 | } | |
1103 | } | |
1104 | ||
1105 | /* if it fails, try another handle if possible - | |
1106 | (we can not do this if closePending since | |
1107 | loop could be modified - in which case we | |
1108 | have to start at the beginning of the list | |
1109 | again. Note that it would be bad | |
1110 | to hold up writepages here (rather than | |
1111 | in caller) with continuous retries */ | |
1112 | cFYI(1, ("wp failed on reopen file")); | |
1113 | read_lock(&GlobalSMBSeslock); | |
1114 | /* can not use this handle, no write | |
1115 | pending on this one after all */ | |
1116 | atomic_dec(&open_file->wrtPending); | |
1117 | ||
1118 | if (open_file->closePend) /* list could have changed */ | |
1119 | goto refind_writable; | |
1120 | /* else we simply continue to the next entry. Thus | |
1121 | we do not loop on reopen errors. If we | |
1122 | can not reopen the file, for example if we | |
1123 | reconnected to a server with another client | |
1124 | racing to delete or lock the file we would not | |
1125 | make progress if we restarted before the beginning | |
1126 | of the loop here. */ | |
1127 | } | |
1128 | } | |
1129 | read_unlock(&GlobalSMBSeslock); | |
1130 | return NULL; | |
1131 | } | |
1132 | ||
1133 | static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to) | |
1134 | { | |
1135 | struct address_space *mapping = page->mapping; | |
1136 | loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT; | |
1137 | char *write_data; | |
1138 | int rc = -EFAULT; | |
1139 | int bytes_written = 0; | |
1140 | struct cifs_sb_info *cifs_sb; | |
1141 | struct cifsTconInfo *pTcon; | |
1142 | struct inode *inode; | |
1143 | struct cifsFileInfo *open_file; | |
1144 | ||
1145 | if (!mapping || !mapping->host) | |
1146 | return -EFAULT; | |
1147 | ||
1148 | inode = page->mapping->host; | |
1149 | cifs_sb = CIFS_SB(inode->i_sb); | |
1150 | pTcon = cifs_sb->tcon; | |
1151 | ||
1152 | offset += (loff_t)from; | |
1153 | write_data = kmap(page); | |
1154 | write_data += from; | |
1155 | ||
1156 | if ((to > PAGE_CACHE_SIZE) || (from > to)) { | |
1157 | kunmap(page); | |
1158 | return -EIO; | |
1159 | } | |
1160 | ||
1161 | /* racing with truncate? */ | |
1162 | if (offset > mapping->host->i_size) { | |
1163 | kunmap(page); | |
1164 | return 0; /* don't care */ | |
1165 | } | |
1166 | ||
1167 | /* check to make sure that we are not extending the file */ | |
1168 | if (mapping->host->i_size - offset < (loff_t)to) | |
1169 | to = (unsigned)(mapping->host->i_size - offset); | |
1170 | ||
1171 | open_file = find_writable_file(CIFS_I(mapping->host)); | |
1172 | if (open_file) { | |
1173 | bytes_written = cifs_write(open_file->pfile, write_data, | |
1174 | to-from, &offset); | |
1175 | atomic_dec(&open_file->wrtPending); | |
1176 | /* Does mm or vfs already set times? */ | |
1177 | inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb); | |
1178 | if ((bytes_written > 0) && (offset)) { | |
1179 | rc = 0; | |
1180 | } else if (bytes_written < 0) { | |
1181 | if (rc != -EBADF) | |
1182 | rc = bytes_written; | |
1183 | } | |
1184 | } else { | |
1185 | cFYI(1, ("No writeable filehandles for inode")); | |
1186 | rc = -EIO; | |
1187 | } | |
1188 | ||
1189 | kunmap(page); | |
1190 | return rc; | |
1191 | } | |
1192 | ||
1193 | static int cifs_writepages(struct address_space *mapping, | |
1194 | struct writeback_control *wbc) | |
1195 | { | |
1196 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
1197 | unsigned int bytes_to_write; | |
1198 | unsigned int bytes_written; | |
1199 | struct cifs_sb_info *cifs_sb; | |
1200 | int done = 0; | |
1201 | pgoff_t end; | |
1202 | pgoff_t index; | |
1203 | int range_whole = 0; | |
1204 | struct kvec *iov; | |
1205 | int len; | |
1206 | int n_iov = 0; | |
1207 | pgoff_t next; | |
1208 | int nr_pages; | |
1209 | __u64 offset = 0; | |
1210 | struct cifsFileInfo *open_file; | |
1211 | struct page *page; | |
1212 | struct pagevec pvec; | |
1213 | int rc = 0; | |
1214 | int scanned = 0; | |
1215 | int xid; | |
1216 | ||
1217 | cifs_sb = CIFS_SB(mapping->host->i_sb); | |
1218 | ||
1219 | /* | |
1220 | * If wsize is smaller that the page cache size, default to writing | |
1221 | * one page at a time via cifs_writepage | |
1222 | */ | |
1223 | if (cifs_sb->wsize < PAGE_CACHE_SIZE) | |
1224 | return generic_writepages(mapping, wbc); | |
1225 | ||
1226 | if ((cifs_sb->tcon->ses) && (cifs_sb->tcon->ses->server)) | |
1227 | if (cifs_sb->tcon->ses->server->secMode & | |
1228 | (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) | |
1229 | if (!experimEnabled) | |
1230 | return generic_writepages(mapping, wbc); | |
1231 | ||
1232 | iov = kmalloc(32 * sizeof(struct kvec), GFP_KERNEL); | |
1233 | if (iov == NULL) | |
1234 | return generic_writepages(mapping, wbc); | |
1235 | ||
1236 | ||
1237 | /* | |
1238 | * BB: Is this meaningful for a non-block-device file system? | |
1239 | * If it is, we should test it again after we do I/O | |
1240 | */ | |
1241 | if (wbc->nonblocking && bdi_write_congested(bdi)) { | |
1242 | wbc->encountered_congestion = 1; | |
1243 | kfree(iov); | |
1244 | return 0; | |
1245 | } | |
1246 | ||
1247 | xid = GetXid(); | |
1248 | ||
1249 | pagevec_init(&pvec, 0); | |
1250 | if (wbc->range_cyclic) { | |
1251 | index = mapping->writeback_index; /* Start from prev offset */ | |
1252 | end = -1; | |
1253 | } else { | |
1254 | index = wbc->range_start >> PAGE_CACHE_SHIFT; | |
1255 | end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
1256 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) | |
1257 | range_whole = 1; | |
1258 | scanned = 1; | |
1259 | } | |
1260 | retry: | |
1261 | while (!done && (index <= end) && | |
1262 | (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, | |
1263 | PAGECACHE_TAG_DIRTY, | |
1264 | min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) { | |
1265 | int first; | |
1266 | unsigned int i; | |
1267 | ||
1268 | first = -1; | |
1269 | next = 0; | |
1270 | n_iov = 0; | |
1271 | bytes_to_write = 0; | |
1272 | ||
1273 | for (i = 0; i < nr_pages; i++) { | |
1274 | page = pvec.pages[i]; | |
1275 | /* | |
1276 | * At this point we hold neither mapping->tree_lock nor | |
1277 | * lock on the page itself: the page may be truncated or | |
1278 | * invalidated (changing page->mapping to NULL), or even | |
1279 | * swizzled back from swapper_space to tmpfs file | |
1280 | * mapping | |
1281 | */ | |
1282 | ||
1283 | if (first < 0) | |
1284 | lock_page(page); | |
1285 | else if (TestSetPageLocked(page)) | |
1286 | break; | |
1287 | ||
1288 | if (unlikely(page->mapping != mapping)) { | |
1289 | unlock_page(page); | |
1290 | break; | |
1291 | } | |
1292 | ||
1293 | if (!wbc->range_cyclic && page->index > end) { | |
1294 | done = 1; | |
1295 | unlock_page(page); | |
1296 | break; | |
1297 | } | |
1298 | ||
1299 | if (next && (page->index != next)) { | |
1300 | /* Not next consecutive page */ | |
1301 | unlock_page(page); | |
1302 | break; | |
1303 | } | |
1304 | ||
1305 | if (wbc->sync_mode != WB_SYNC_NONE) | |
1306 | wait_on_page_writeback(page); | |
1307 | ||
1308 | if (PageWriteback(page) || | |
1309 | !clear_page_dirty_for_io(page)) { | |
1310 | unlock_page(page); | |
1311 | break; | |
1312 | } | |
1313 | ||
1314 | /* | |
1315 | * This actually clears the dirty bit in the radix tree. | |
1316 | * See cifs_writepage() for more commentary. | |
1317 | */ | |
1318 | set_page_writeback(page); | |
1319 | ||
1320 | if (page_offset(page) >= mapping->host->i_size) { | |
1321 | done = 1; | |
1322 | unlock_page(page); | |
1323 | end_page_writeback(page); | |
1324 | break; | |
1325 | } | |
1326 | ||
1327 | /* | |
1328 | * BB can we get rid of this? pages are held by pvec | |
1329 | */ | |
1330 | page_cache_get(page); | |
1331 | ||
1332 | len = min(mapping->host->i_size - page_offset(page), | |
1333 | (loff_t)PAGE_CACHE_SIZE); | |
1334 | ||
1335 | /* reserve iov[0] for the smb header */ | |
1336 | n_iov++; | |
1337 | iov[n_iov].iov_base = kmap(page); | |
1338 | iov[n_iov].iov_len = len; | |
1339 | bytes_to_write += len; | |
1340 | ||
1341 | if (first < 0) { | |
1342 | first = i; | |
1343 | offset = page_offset(page); | |
1344 | } | |
1345 | next = page->index + 1; | |
1346 | if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize) | |
1347 | break; | |
1348 | } | |
1349 | if (n_iov) { | |
1350 | /* Search for a writable handle every time we call | |
1351 | * CIFSSMBWrite2. We can't rely on the last handle | |
1352 | * we used to still be valid | |
1353 | */ | |
1354 | open_file = find_writable_file(CIFS_I(mapping->host)); | |
1355 | if (!open_file) { | |
1356 | cERROR(1, ("No writable handles for inode")); | |
1357 | rc = -EBADF; | |
1358 | } else { | |
1359 | rc = CIFSSMBWrite2(xid, cifs_sb->tcon, | |
1360 | open_file->netfid, | |
1361 | bytes_to_write, offset, | |
1362 | &bytes_written, iov, n_iov, | |
1363 | CIFS_LONG_OP); | |
1364 | atomic_dec(&open_file->wrtPending); | |
1365 | if (rc || bytes_written < bytes_to_write) { | |
1366 | cERROR(1, ("Write2 ret %d, wrote %d", | |
1367 | rc, bytes_written)); | |
1368 | /* BB what if continued retry is | |
1369 | requested via mount flags? */ | |
1370 | set_bit(AS_EIO, &mapping->flags); | |
1371 | } else { | |
1372 | cifs_stats_bytes_written(cifs_sb->tcon, | |
1373 | bytes_written); | |
1374 | } | |
1375 | } | |
1376 | for (i = 0; i < n_iov; i++) { | |
1377 | page = pvec.pages[first + i]; | |
1378 | /* Should we also set page error on | |
1379 | success rc but too little data written? */ | |
1380 | /* BB investigate retry logic on temporary | |
1381 | server crash cases and how recovery works | |
1382 | when page marked as error */ | |
1383 | if (rc) | |
1384 | SetPageError(page); | |
1385 | kunmap(page); | |
1386 | unlock_page(page); | |
1387 | end_page_writeback(page); | |
1388 | page_cache_release(page); | |
1389 | } | |
1390 | if ((wbc->nr_to_write -= n_iov) <= 0) | |
1391 | done = 1; | |
1392 | index = next; | |
1393 | } | |
1394 | pagevec_release(&pvec); | |
1395 | } | |
1396 | if (!scanned && !done) { | |
1397 | /* | |
1398 | * We hit the last page and there is more work to be done: wrap | |
1399 | * back to the start of the file | |
1400 | */ | |
1401 | scanned = 1; | |
1402 | index = 0; | |
1403 | goto retry; | |
1404 | } | |
1405 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) | |
1406 | mapping->writeback_index = index; | |
1407 | ||
1408 | FreeXid(xid); | |
1409 | kfree(iov); | |
1410 | return rc; | |
1411 | } | |
1412 | ||
1413 | static int cifs_writepage(struct page *page, struct writeback_control *wbc) | |
1414 | { | |
1415 | int rc = -EFAULT; | |
1416 | int xid; | |
1417 | ||
1418 | xid = GetXid(); | |
1419 | /* BB add check for wbc flags */ | |
1420 | page_cache_get(page); | |
1421 | if (!PageUptodate(page)) { | |
1422 | cFYI(1, ("ppw - page not up to date")); | |
1423 | } | |
1424 | ||
1425 | /* | |
1426 | * Set the "writeback" flag, and clear "dirty" in the radix tree. | |
1427 | * | |
1428 | * A writepage() implementation always needs to do either this, | |
1429 | * or re-dirty the page with "redirty_page_for_writepage()" in | |
1430 | * the case of a failure. | |
1431 | * | |
1432 | * Just unlocking the page will cause the radix tree tag-bits | |
1433 | * to fail to update with the state of the page correctly. | |
1434 | */ | |
1435 | set_page_writeback(page); | |
1436 | rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE); | |
1437 | SetPageUptodate(page); /* BB add check for error and Clearuptodate? */ | |
1438 | unlock_page(page); | |
1439 | end_page_writeback(page); | |
1440 | page_cache_release(page); | |
1441 | FreeXid(xid); | |
1442 | return rc; | |
1443 | } | |
1444 | ||
1445 | static int cifs_commit_write(struct file *file, struct page *page, | |
1446 | unsigned offset, unsigned to) | |
1447 | { | |
1448 | int xid; | |
1449 | int rc = 0; | |
1450 | struct inode *inode = page->mapping->host; | |
1451 | loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
1452 | char *page_data; | |
1453 | ||
1454 | xid = GetXid(); | |
1455 | cFYI(1, ("commit write for page %p up to position %lld for %d", | |
1456 | page, position, to)); | |
1457 | spin_lock(&inode->i_lock); | |
1458 | if (position > inode->i_size) { | |
1459 | i_size_write(inode, position); | |
1460 | } | |
1461 | spin_unlock(&inode->i_lock); | |
1462 | if (!PageUptodate(page)) { | |
1463 | position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset; | |
1464 | /* can not rely on (or let) writepage write this data */ | |
1465 | if (to < offset) { | |
1466 | cFYI(1, ("Illegal offsets, can not copy from %d to %d", | |
1467 | offset, to)); | |
1468 | FreeXid(xid); | |
1469 | return rc; | |
1470 | } | |
1471 | /* this is probably better than directly calling | |
1472 | partialpage_write since in this function the file handle is | |
1473 | known which we might as well leverage */ | |
1474 | /* BB check if anything else missing out of ppw | |
1475 | such as updating last write time */ | |
1476 | page_data = kmap(page); | |
1477 | rc = cifs_write(file, page_data + offset, to-offset, | |
1478 | &position); | |
1479 | if (rc > 0) | |
1480 | rc = 0; | |
1481 | /* else if (rc < 0) should we set writebehind rc? */ | |
1482 | kunmap(page); | |
1483 | } else { | |
1484 | set_page_dirty(page); | |
1485 | } | |
1486 | ||
1487 | FreeXid(xid); | |
1488 | return rc; | |
1489 | } | |
1490 | ||
1491 | int cifs_fsync(struct file *file, struct dentry *dentry, int datasync) | |
1492 | { | |
1493 | int xid; | |
1494 | int rc = 0; | |
1495 | struct inode *inode = file->f_path.dentry->d_inode; | |
1496 | ||
1497 | xid = GetXid(); | |
1498 | ||
1499 | cFYI(1, ("Sync file - name: %s datasync: 0x%x", | |
1500 | dentry->d_name.name, datasync)); | |
1501 | ||
1502 | rc = filemap_fdatawrite(inode->i_mapping); | |
1503 | if (rc == 0) | |
1504 | CIFS_I(inode)->write_behind_rc = 0; | |
1505 | FreeXid(xid); | |
1506 | return rc; | |
1507 | } | |
1508 | ||
1509 | /* static void cifs_sync_page(struct page *page) | |
1510 | { | |
1511 | struct address_space *mapping; | |
1512 | struct inode *inode; | |
1513 | unsigned long index = page->index; | |
1514 | unsigned int rpages = 0; | |
1515 | int rc = 0; | |
1516 | ||
1517 | cFYI(1, ("sync page %p",page)); | |
1518 | mapping = page->mapping; | |
1519 | if (!mapping) | |
1520 | return 0; | |
1521 | inode = mapping->host; | |
1522 | if (!inode) | |
1523 | return; */ | |
1524 | ||
1525 | /* fill in rpages then | |
1526 | result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */ | |
1527 | ||
1528 | /* cFYI(1, ("rpages is %d for sync page of Index %ld", rpages, index)); | |
1529 | ||
1530 | #if 0 | |
1531 | if (rc < 0) | |
1532 | return rc; | |
1533 | return 0; | |
1534 | #endif | |
1535 | } */ | |
1536 | ||
1537 | /* | |
1538 | * As file closes, flush all cached write data for this inode checking | |
1539 | * for write behind errors. | |
1540 | */ | |
1541 | int cifs_flush(struct file *file, fl_owner_t id) | |
1542 | { | |
1543 | struct inode *inode = file->f_path.dentry->d_inode; | |
1544 | int rc = 0; | |
1545 | ||
1546 | /* Rather than do the steps manually: | |
1547 | lock the inode for writing | |
1548 | loop through pages looking for write behind data (dirty pages) | |
1549 | coalesce into contiguous 16K (or smaller) chunks to write to server | |
1550 | send to server (prefer in parallel) | |
1551 | deal with writebehind errors | |
1552 | unlock inode for writing | |
1553 | filemapfdatawrite appears easier for the time being */ | |
1554 | ||
1555 | rc = filemap_fdatawrite(inode->i_mapping); | |
1556 | if (!rc) /* reset wb rc if we were able to write out dirty pages */ | |
1557 | CIFS_I(inode)->write_behind_rc = 0; | |
1558 | ||
1559 | cFYI(1, ("Flush inode %p file %p rc %d", inode, file, rc)); | |
1560 | ||
1561 | return rc; | |
1562 | } | |
1563 | ||
1564 | ssize_t cifs_user_read(struct file *file, char __user *read_data, | |
1565 | size_t read_size, loff_t *poffset) | |
1566 | { | |
1567 | int rc = -EACCES; | |
1568 | unsigned int bytes_read = 0; | |
1569 | unsigned int total_read = 0; | |
1570 | unsigned int current_read_size; | |
1571 | struct cifs_sb_info *cifs_sb; | |
1572 | struct cifsTconInfo *pTcon; | |
1573 | int xid; | |
1574 | struct cifsFileInfo *open_file; | |
1575 | char *smb_read_data; | |
1576 | char __user *current_offset; | |
1577 | struct smb_com_read_rsp *pSMBr; | |
1578 | ||
1579 | xid = GetXid(); | |
1580 | cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); | |
1581 | pTcon = cifs_sb->tcon; | |
1582 | ||
1583 | if (file->private_data == NULL) { | |
1584 | FreeXid(xid); | |
1585 | return -EBADF; | |
1586 | } | |
1587 | open_file = (struct cifsFileInfo *)file->private_data; | |
1588 | ||
1589 | if ((file->f_flags & O_ACCMODE) == O_WRONLY) { | |
1590 | cFYI(1, ("attempting read on write only file instance")); | |
1591 | } | |
1592 | for (total_read = 0, current_offset = read_data; | |
1593 | read_size > total_read; | |
1594 | total_read += bytes_read, current_offset += bytes_read) { | |
1595 | current_read_size = min_t(const int, read_size - total_read, | |
1596 | cifs_sb->rsize); | |
1597 | rc = -EAGAIN; | |
1598 | smb_read_data = NULL; | |
1599 | while (rc == -EAGAIN) { | |
1600 | int buf_type = CIFS_NO_BUFFER; | |
1601 | if ((open_file->invalidHandle) && | |
1602 | (!open_file->closePend)) { | |
1603 | rc = cifs_reopen_file(file, TRUE); | |
1604 | if (rc != 0) | |
1605 | break; | |
1606 | } | |
1607 | rc = CIFSSMBRead(xid, pTcon, | |
1608 | open_file->netfid, | |
1609 | current_read_size, *poffset, | |
1610 | &bytes_read, &smb_read_data, | |
1611 | &buf_type); | |
1612 | pSMBr = (struct smb_com_read_rsp *)smb_read_data; | |
1613 | if (smb_read_data) { | |
1614 | if (copy_to_user(current_offset, | |
1615 | smb_read_data + | |
1616 | 4 /* RFC1001 length field */ + | |
1617 | le16_to_cpu(pSMBr->DataOffset), | |
1618 | bytes_read)) { | |
1619 | rc = -EFAULT; | |
1620 | } | |
1621 | ||
1622 | if (buf_type == CIFS_SMALL_BUFFER) | |
1623 | cifs_small_buf_release(smb_read_data); | |
1624 | else if (buf_type == CIFS_LARGE_BUFFER) | |
1625 | cifs_buf_release(smb_read_data); | |
1626 | smb_read_data = NULL; | |
1627 | } | |
1628 | } | |
1629 | if (rc || (bytes_read == 0)) { | |
1630 | if (total_read) { | |
1631 | break; | |
1632 | } else { | |
1633 | FreeXid(xid); | |
1634 | return rc; | |
1635 | } | |
1636 | } else { | |
1637 | cifs_stats_bytes_read(pTcon, bytes_read); | |
1638 | *poffset += bytes_read; | |
1639 | } | |
1640 | } | |
1641 | FreeXid(xid); | |
1642 | return total_read; | |
1643 | } | |
1644 | ||
1645 | ||
1646 | static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size, | |
1647 | loff_t *poffset) | |
1648 | { | |
1649 | int rc = -EACCES; | |
1650 | unsigned int bytes_read = 0; | |
1651 | unsigned int total_read; | |
1652 | unsigned int current_read_size; | |
1653 | struct cifs_sb_info *cifs_sb; | |
1654 | struct cifsTconInfo *pTcon; | |
1655 | int xid; | |
1656 | char *current_offset; | |
1657 | struct cifsFileInfo *open_file; | |
1658 | int buf_type = CIFS_NO_BUFFER; | |
1659 | ||
1660 | xid = GetXid(); | |
1661 | cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); | |
1662 | pTcon = cifs_sb->tcon; | |
1663 | ||
1664 | if (file->private_data == NULL) { | |
1665 | FreeXid(xid); | |
1666 | return -EBADF; | |
1667 | } | |
1668 | open_file = (struct cifsFileInfo *)file->private_data; | |
1669 | ||
1670 | if ((file->f_flags & O_ACCMODE) == O_WRONLY) | |
1671 | cFYI(1, ("attempting read on write only file instance")); | |
1672 | ||
1673 | for (total_read = 0, current_offset = read_data; | |
1674 | read_size > total_read; | |
1675 | total_read += bytes_read, current_offset += bytes_read) { | |
1676 | current_read_size = min_t(const int, read_size - total_read, | |
1677 | cifs_sb->rsize); | |
1678 | /* For windows me and 9x we do not want to request more | |
1679 | than it negotiated since it will refuse the read then */ | |
1680 | if ((pTcon->ses) && | |
1681 | !(pTcon->ses->capabilities & CAP_LARGE_FILES)) { | |
1682 | current_read_size = min_t(const int, current_read_size, | |
1683 | pTcon->ses->server->maxBuf - 128); | |
1684 | } | |
1685 | rc = -EAGAIN; | |
1686 | while (rc == -EAGAIN) { | |
1687 | if ((open_file->invalidHandle) && | |
1688 | (!open_file->closePend)) { | |
1689 | rc = cifs_reopen_file(file, TRUE); | |
1690 | if (rc != 0) | |
1691 | break; | |
1692 | } | |
1693 | rc = CIFSSMBRead(xid, pTcon, | |
1694 | open_file->netfid, | |
1695 | current_read_size, *poffset, | |
1696 | &bytes_read, ¤t_offset, | |
1697 | &buf_type); | |
1698 | } | |
1699 | if (rc || (bytes_read == 0)) { | |
1700 | if (total_read) { | |
1701 | break; | |
1702 | } else { | |
1703 | FreeXid(xid); | |
1704 | return rc; | |
1705 | } | |
1706 | } else { | |
1707 | cifs_stats_bytes_read(pTcon, total_read); | |
1708 | *poffset += bytes_read; | |
1709 | } | |
1710 | } | |
1711 | FreeXid(xid); | |
1712 | return total_read; | |
1713 | } | |
1714 | ||
1715 | int cifs_file_mmap(struct file *file, struct vm_area_struct *vma) | |
1716 | { | |
1717 | struct dentry *dentry = file->f_path.dentry; | |
1718 | int rc, xid; | |
1719 | ||
1720 | xid = GetXid(); | |
1721 | rc = cifs_revalidate(dentry); | |
1722 | if (rc) { | |
1723 | cFYI(1, ("Validation prior to mmap failed, error=%d", rc)); | |
1724 | FreeXid(xid); | |
1725 | return rc; | |
1726 | } | |
1727 | rc = generic_file_mmap(file, vma); | |
1728 | FreeXid(xid); | |
1729 | return rc; | |
1730 | } | |
1731 | ||
1732 | ||
1733 | static void cifs_copy_cache_pages(struct address_space *mapping, | |
1734 | struct list_head *pages, int bytes_read, char *data, | |
1735 | struct pagevec *plru_pvec) | |
1736 | { | |
1737 | struct page *page; | |
1738 | char *target; | |
1739 | ||
1740 | while (bytes_read > 0) { | |
1741 | if (list_empty(pages)) | |
1742 | break; | |
1743 | ||
1744 | page = list_entry(pages->prev, struct page, lru); | |
1745 | list_del(&page->lru); | |
1746 | ||
1747 | if (add_to_page_cache(page, mapping, page->index, | |
1748 | GFP_KERNEL)) { | |
1749 | page_cache_release(page); | |
1750 | cFYI(1, ("Add page cache failed")); | |
1751 | data += PAGE_CACHE_SIZE; | |
1752 | bytes_read -= PAGE_CACHE_SIZE; | |
1753 | continue; | |
1754 | } | |
1755 | ||
1756 | target = kmap_atomic(page, KM_USER0); | |
1757 | ||
1758 | if (PAGE_CACHE_SIZE > bytes_read) { | |
1759 | memcpy(target, data, bytes_read); | |
1760 | /* zero the tail end of this partial page */ | |
1761 | memset(target + bytes_read, 0, | |
1762 | PAGE_CACHE_SIZE - bytes_read); | |
1763 | bytes_read = 0; | |
1764 | } else { | |
1765 | memcpy(target, data, PAGE_CACHE_SIZE); | |
1766 | bytes_read -= PAGE_CACHE_SIZE; | |
1767 | } | |
1768 | kunmap_atomic(target, KM_USER0); | |
1769 | ||
1770 | flush_dcache_page(page); | |
1771 | SetPageUptodate(page); | |
1772 | unlock_page(page); | |
1773 | if (!pagevec_add(plru_pvec, page)) | |
1774 | __pagevec_lru_add(plru_pvec); | |
1775 | data += PAGE_CACHE_SIZE; | |
1776 | } | |
1777 | return; | |
1778 | } | |
1779 | ||
1780 | static int cifs_readpages(struct file *file, struct address_space *mapping, | |
1781 | struct list_head *page_list, unsigned num_pages) | |
1782 | { | |
1783 | int rc = -EACCES; | |
1784 | int xid; | |
1785 | loff_t offset; | |
1786 | struct page *page; | |
1787 | struct cifs_sb_info *cifs_sb; | |
1788 | struct cifsTconInfo *pTcon; | |
1789 | unsigned int bytes_read = 0; | |
1790 | unsigned int read_size, i; | |
1791 | char *smb_read_data = NULL; | |
1792 | struct smb_com_read_rsp *pSMBr; | |
1793 | struct pagevec lru_pvec; | |
1794 | struct cifsFileInfo *open_file; | |
1795 | int buf_type = CIFS_NO_BUFFER; | |
1796 | ||
1797 | xid = GetXid(); | |
1798 | if (file->private_data == NULL) { | |
1799 | FreeXid(xid); | |
1800 | return -EBADF; | |
1801 | } | |
1802 | open_file = (struct cifsFileInfo *)file->private_data; | |
1803 | cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); | |
1804 | pTcon = cifs_sb->tcon; | |
1805 | ||
1806 | pagevec_init(&lru_pvec, 0); | |
1807 | #ifdef CONFIG_CIFS_DEBUG2 | |
1808 | cFYI(1, ("rpages: num pages %d", num_pages)); | |
1809 | #endif | |
1810 | for (i = 0; i < num_pages; ) { | |
1811 | unsigned contig_pages; | |
1812 | struct page *tmp_page; | |
1813 | unsigned long expected_index; | |
1814 | ||
1815 | if (list_empty(page_list)) | |
1816 | break; | |
1817 | ||
1818 | page = list_entry(page_list->prev, struct page, lru); | |
1819 | offset = (loff_t)page->index << PAGE_CACHE_SHIFT; | |
1820 | ||
1821 | /* count adjacent pages that we will read into */ | |
1822 | contig_pages = 0; | |
1823 | expected_index = | |
1824 | list_entry(page_list->prev, struct page, lru)->index; | |
1825 | list_for_each_entry_reverse(tmp_page, page_list, lru) { | |
1826 | if (tmp_page->index == expected_index) { | |
1827 | contig_pages++; | |
1828 | expected_index++; | |
1829 | } else | |
1830 | break; | |
1831 | } | |
1832 | if (contig_pages + i > num_pages) | |
1833 | contig_pages = num_pages - i; | |
1834 | ||
1835 | /* for reads over a certain size could initiate async | |
1836 | read ahead */ | |
1837 | ||
1838 | read_size = contig_pages * PAGE_CACHE_SIZE; | |
1839 | /* Read size needs to be in multiples of one page */ | |
1840 | read_size = min_t(const unsigned int, read_size, | |
1841 | cifs_sb->rsize & PAGE_CACHE_MASK); | |
1842 | #ifdef CONFIG_CIFS_DEBUG2 | |
1843 | cFYI(1, ("rpages: read size 0x%x contiguous pages %d", | |
1844 | read_size, contig_pages)); | |
1845 | #endif | |
1846 | rc = -EAGAIN; | |
1847 | while (rc == -EAGAIN) { | |
1848 | if ((open_file->invalidHandle) && | |
1849 | (!open_file->closePend)) { | |
1850 | rc = cifs_reopen_file(file, TRUE); | |
1851 | if (rc != 0) | |
1852 | break; | |
1853 | } | |
1854 | ||
1855 | rc = CIFSSMBRead(xid, pTcon, | |
1856 | open_file->netfid, | |
1857 | read_size, offset, | |
1858 | &bytes_read, &smb_read_data, | |
1859 | &buf_type); | |
1860 | /* BB more RC checks ? */ | |
1861 | if (rc == -EAGAIN) { | |
1862 | if (smb_read_data) { | |
1863 | if (buf_type == CIFS_SMALL_BUFFER) | |
1864 | cifs_small_buf_release(smb_read_data); | |
1865 | else if (buf_type == CIFS_LARGE_BUFFER) | |
1866 | cifs_buf_release(smb_read_data); | |
1867 | smb_read_data = NULL; | |
1868 | } | |
1869 | } | |
1870 | } | |
1871 | if ((rc < 0) || (smb_read_data == NULL)) { | |
1872 | cFYI(1, ("Read error in readpages: %d", rc)); | |
1873 | break; | |
1874 | } else if (bytes_read > 0) { | |
1875 | task_io_account_read(bytes_read); | |
1876 | pSMBr = (struct smb_com_read_rsp *)smb_read_data; | |
1877 | cifs_copy_cache_pages(mapping, page_list, bytes_read, | |
1878 | smb_read_data + 4 /* RFC1001 hdr */ + | |
1879 | le16_to_cpu(pSMBr->DataOffset), &lru_pvec); | |
1880 | ||
1881 | i += bytes_read >> PAGE_CACHE_SHIFT; | |
1882 | cifs_stats_bytes_read(pTcon, bytes_read); | |
1883 | if ((bytes_read & PAGE_CACHE_MASK) != bytes_read) { | |
1884 | i++; /* account for partial page */ | |
1885 | ||
1886 | /* server copy of file can have smaller size | |
1887 | than client */ | |
1888 | /* BB do we need to verify this common case ? | |
1889 | this case is ok - if we are at server EOF | |
1890 | we will hit it on next read */ | |
1891 | ||
1892 | /* break; */ | |
1893 | } | |
1894 | } else { | |
1895 | cFYI(1, ("No bytes read (%d) at offset %lld . " | |
1896 | "Cleaning remaining pages from readahead list", | |
1897 | bytes_read, offset)); | |
1898 | /* BB turn off caching and do new lookup on | |
1899 | file size at server? */ | |
1900 | break; | |
1901 | } | |
1902 | if (smb_read_data) { | |
1903 | if (buf_type == CIFS_SMALL_BUFFER) | |
1904 | cifs_small_buf_release(smb_read_data); | |
1905 | else if (buf_type == CIFS_LARGE_BUFFER) | |
1906 | cifs_buf_release(smb_read_data); | |
1907 | smb_read_data = NULL; | |
1908 | } | |
1909 | bytes_read = 0; | |
1910 | } | |
1911 | ||
1912 | pagevec_lru_add(&lru_pvec); | |
1913 | ||
1914 | /* need to free smb_read_data buf before exit */ | |
1915 | if (smb_read_data) { | |
1916 | if (buf_type == CIFS_SMALL_BUFFER) | |
1917 | cifs_small_buf_release(smb_read_data); | |
1918 | else if (buf_type == CIFS_LARGE_BUFFER) | |
1919 | cifs_buf_release(smb_read_data); | |
1920 | smb_read_data = NULL; | |
1921 | } | |
1922 | ||
1923 | FreeXid(xid); | |
1924 | return rc; | |
1925 | } | |
1926 | ||
1927 | static int cifs_readpage_worker(struct file *file, struct page *page, | |
1928 | loff_t *poffset) | |
1929 | { | |
1930 | char *read_data; | |
1931 | int rc; | |
1932 | ||
1933 | page_cache_get(page); | |
1934 | read_data = kmap(page); | |
1935 | /* for reads over a certain size could initiate async read ahead */ | |
1936 | ||
1937 | rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset); | |
1938 | ||
1939 | if (rc < 0) | |
1940 | goto io_error; | |
1941 | else | |
1942 | cFYI(1, ("Bytes read %d", rc)); | |
1943 | ||
1944 | file->f_path.dentry->d_inode->i_atime = | |
1945 | current_fs_time(file->f_path.dentry->d_inode->i_sb); | |
1946 | ||
1947 | if (PAGE_CACHE_SIZE > rc) | |
1948 | memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc); | |
1949 | ||
1950 | flush_dcache_page(page); | |
1951 | SetPageUptodate(page); | |
1952 | rc = 0; | |
1953 | ||
1954 | io_error: | |
1955 | kunmap(page); | |
1956 | page_cache_release(page); | |
1957 | return rc; | |
1958 | } | |
1959 | ||
1960 | static int cifs_readpage(struct file *file, struct page *page) | |
1961 | { | |
1962 | loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT; | |
1963 | int rc = -EACCES; | |
1964 | int xid; | |
1965 | ||
1966 | xid = GetXid(); | |
1967 | ||
1968 | if (file->private_data == NULL) { | |
1969 | FreeXid(xid); | |
1970 | return -EBADF; | |
1971 | } | |
1972 | ||
1973 | cFYI(1, ("readpage %p at offset %d 0x%x\n", | |
1974 | page, (int)offset, (int)offset)); | |
1975 | ||
1976 | rc = cifs_readpage_worker(file, page, &offset); | |
1977 | ||
1978 | unlock_page(page); | |
1979 | ||
1980 | FreeXid(xid); | |
1981 | return rc; | |
1982 | } | |
1983 | ||
1984 | static int is_inode_writable(struct cifsInodeInfo *cifs_inode) | |
1985 | { | |
1986 | struct cifsFileInfo *open_file; | |
1987 | ||
1988 | read_lock(&GlobalSMBSeslock); | |
1989 | list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { | |
1990 | if (open_file->closePend) | |
1991 | continue; | |
1992 | if (open_file->pfile && | |
1993 | ((open_file->pfile->f_flags & O_RDWR) || | |
1994 | (open_file->pfile->f_flags & O_WRONLY))) { | |
1995 | read_unlock(&GlobalSMBSeslock); | |
1996 | return 1; | |
1997 | } | |
1998 | } | |
1999 | read_unlock(&GlobalSMBSeslock); | |
2000 | return 0; | |
2001 | } | |
2002 | ||
2003 | /* We do not want to update the file size from server for inodes | |
2004 | open for write - to avoid races with writepage extending | |
2005 | the file - in the future we could consider allowing | |
2006 | refreshing the inode only on increases in the file size | |
2007 | but this is tricky to do without racing with writebehind | |
2008 | page caching in the current Linux kernel design */ | |
2009 | int is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file) | |
2010 | { | |
2011 | if (!cifsInode) | |
2012 | return 1; | |
2013 | ||
2014 | if (is_inode_writable(cifsInode)) { | |
2015 | /* This inode is open for write at least once */ | |
2016 | struct cifs_sb_info *cifs_sb; | |
2017 | ||
2018 | cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb); | |
2019 | if ( cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO ) { | |
2020 | /* since no page cache to corrupt on directio | |
2021 | we can change size safely */ | |
2022 | return 1; | |
2023 | } | |
2024 | ||
2025 | if (i_size_read(&cifsInode->vfs_inode) < end_of_file) | |
2026 | return 1; | |
2027 | ||
2028 | return 0; | |
2029 | } else | |
2030 | return 1; | |
2031 | } | |
2032 | ||
2033 | static int cifs_prepare_write(struct file *file, struct page *page, | |
2034 | unsigned from, unsigned to) | |
2035 | { | |
2036 | int rc = 0; | |
2037 | loff_t i_size; | |
2038 | loff_t offset; | |
2039 | ||
2040 | cFYI(1, ("prepare write for page %p from %d to %d", page, from, to)); | |
2041 | if (PageUptodate(page)) | |
2042 | return 0; | |
2043 | ||
2044 | /* If we are writing a full page it will be up to date, | |
2045 | no need to read from the server */ | |
2046 | if ((to == PAGE_CACHE_SIZE) && (from == 0)) { | |
2047 | SetPageUptodate(page); | |
2048 | return 0; | |
2049 | } | |
2050 | ||
2051 | offset = (loff_t)page->index << PAGE_CACHE_SHIFT; | |
2052 | i_size = i_size_read(page->mapping->host); | |
2053 | ||
2054 | if ((offset >= i_size) || | |
2055 | ((from == 0) && (offset + to) >= i_size)) { | |
2056 | /* | |
2057 | * We don't need to read data beyond the end of the file. | |
2058 | * zero it, and set the page uptodate | |
2059 | */ | |
2060 | simple_prepare_write(file, page, from, to); | |
2061 | SetPageUptodate(page); | |
2062 | } else if ((file->f_flags & O_ACCMODE) != O_WRONLY) { | |
2063 | /* might as well read a page, it is fast enough */ | |
2064 | rc = cifs_readpage_worker(file, page, &offset); | |
2065 | } else { | |
2066 | /* we could try using another file handle if there is one - | |
2067 | but how would we lock it to prevent close of that handle | |
2068 | racing with this read? In any case | |
2069 | this will be written out by commit_write so is fine */ | |
2070 | } | |
2071 | ||
2072 | /* we do not need to pass errors back | |
2073 | e.g. if we do not have read access to the file | |
2074 | because cifs_commit_write will do the right thing. -- shaggy */ | |
2075 | ||
2076 | return 0; | |
2077 | } | |
2078 | ||
2079 | const struct address_space_operations cifs_addr_ops = { | |
2080 | .readpage = cifs_readpage, | |
2081 | .readpages = cifs_readpages, | |
2082 | .writepage = cifs_writepage, | |
2083 | .writepages = cifs_writepages, | |
2084 | .prepare_write = cifs_prepare_write, | |
2085 | .commit_write = cifs_commit_write, | |
2086 | .set_page_dirty = __set_page_dirty_nobuffers, | |
2087 | /* .sync_page = cifs_sync_page, */ | |
2088 | /* .direct_IO = */ | |
2089 | }; | |
2090 | ||
2091 | /* | |
2092 | * cifs_readpages requires the server to support a buffer large enough to | |
2093 | * contain the header plus one complete page of data. Otherwise, we need | |
2094 | * to leave cifs_readpages out of the address space operations. | |
2095 | */ | |
2096 | const struct address_space_operations cifs_addr_ops_smallbuf = { | |
2097 | .readpage = cifs_readpage, | |
2098 | .writepage = cifs_writepage, | |
2099 | .writepages = cifs_writepages, | |
2100 | .prepare_write = cifs_prepare_write, | |
2101 | .commit_write = cifs_commit_write, | |
2102 | .set_page_dirty = __set_page_dirty_nobuffers, | |
2103 | /* .sync_page = cifs_sync_page, */ | |
2104 | /* .direct_IO = */ | |
2105 | }; |