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1/*
2 * fs/cifs/misc.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/slab.h>
23#include <linux/ctype.h>
24#include <linux/mempool.h>
25#include "cifspdu.h"
26#include "cifsglob.h"
27#include "cifsproto.h"
28#include "cifs_debug.h"
29#include "smberr.h"
30#include "nterr.h"
31#include "cifs_unicode.h"
32#ifdef CONFIG_CIFS_SMB2
33#include "smb2pdu.h"
34#endif
35
36extern mempool_t *cifs_sm_req_poolp;
37extern mempool_t *cifs_req_poolp;
38
39/* The xid serves as a useful identifier for each incoming vfs request,
40 in a similar way to the mid which is useful to track each sent smb,
41 and CurrentXid can also provide a running counter (although it
42 will eventually wrap past zero) of the total vfs operations handled
43 since the cifs fs was mounted */
44
45unsigned int
46_get_xid(void)
47{
48 unsigned int xid;
49
50 spin_lock(&GlobalMid_Lock);
51 GlobalTotalActiveXid++;
52
53 /* keep high water mark for number of simultaneous ops in filesystem */
54 if (GlobalTotalActiveXid > GlobalMaxActiveXid)
55 GlobalMaxActiveXid = GlobalTotalActiveXid;
56 if (GlobalTotalActiveXid > 65000)
57 cifs_dbg(FYI, "warning: more than 65000 requests active\n");
58 xid = GlobalCurrentXid++;
59 spin_unlock(&GlobalMid_Lock);
60 return xid;
61}
62
63void
64_free_xid(unsigned int xid)
65{
66 spin_lock(&GlobalMid_Lock);
67 /* if (GlobalTotalActiveXid == 0)
68 BUG(); */
69 GlobalTotalActiveXid--;
70 spin_unlock(&GlobalMid_Lock);
71}
72
73struct cifs_ses *
74sesInfoAlloc(void)
75{
76 struct cifs_ses *ret_buf;
77
78 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);
79 if (ret_buf) {
80 atomic_inc(&sesInfoAllocCount);
81 ret_buf->status = CifsNew;
82 ++ret_buf->ses_count;
83 INIT_LIST_HEAD(&ret_buf->smb_ses_list);
84 INIT_LIST_HEAD(&ret_buf->tcon_list);
85 mutex_init(&ret_buf->session_mutex);
86 }
87 return ret_buf;
88}
89
90void
91sesInfoFree(struct cifs_ses *buf_to_free)
92{
93 if (buf_to_free == NULL) {
94 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n");
95 return;
96 }
97
98 atomic_dec(&sesInfoAllocCount);
99 kfree(buf_to_free->serverOS);
100 kfree(buf_to_free->serverDomain);
101 kfree(buf_to_free->serverNOS);
102 if (buf_to_free->password) {
103 memset(buf_to_free->password, 0, strlen(buf_to_free->password));
104 kfree(buf_to_free->password);
105 }
106 kfree(buf_to_free->user_name);
107 kfree(buf_to_free->domainName);
108 kfree(buf_to_free->auth_key.response);
109 kfree(buf_to_free);
110}
111
112struct cifs_tcon *
113tconInfoAlloc(void)
114{
115 struct cifs_tcon *ret_buf;
116 ret_buf = kzalloc(sizeof(struct cifs_tcon), GFP_KERNEL);
117 if (ret_buf) {
118 atomic_inc(&tconInfoAllocCount);
119 ret_buf->tidStatus = CifsNew;
120 ++ret_buf->tc_count;
121 INIT_LIST_HEAD(&ret_buf->openFileList);
122 INIT_LIST_HEAD(&ret_buf->tcon_list);
123#ifdef CONFIG_CIFS_STATS
124 spin_lock_init(&ret_buf->stat_lock);
125#endif
126 }
127 return ret_buf;
128}
129
130void
131tconInfoFree(struct cifs_tcon *buf_to_free)
132{
133 if (buf_to_free == NULL) {
134 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n");
135 return;
136 }
137 atomic_dec(&tconInfoAllocCount);
138 kfree(buf_to_free->nativeFileSystem);
139 if (buf_to_free->password) {
140 memset(buf_to_free->password, 0, strlen(buf_to_free->password));
141 kfree(buf_to_free->password);
142 }
143 kfree(buf_to_free);
144}
145
146struct smb_hdr *
147cifs_buf_get(void)
148{
149 struct smb_hdr *ret_buf = NULL;
150 size_t buf_size = sizeof(struct smb_hdr);
151
152#ifdef CONFIG_CIFS_SMB2
153 /*
154 * SMB2 header is bigger than CIFS one - no problems to clean some
155 * more bytes for CIFS.
156 */
157 buf_size = sizeof(struct smb2_hdr);
158#endif
159 /*
160 * We could use negotiated size instead of max_msgsize -
161 * but it may be more efficient to always alloc same size
162 * albeit slightly larger than necessary and maxbuffersize
163 * defaults to this and can not be bigger.
164 */
165 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
166
167 /* clear the first few header bytes */
168 /* for most paths, more is cleared in header_assemble */
169 if (ret_buf) {
170 memset(ret_buf, 0, buf_size + 3);
171 atomic_inc(&bufAllocCount);
172#ifdef CONFIG_CIFS_STATS2
173 atomic_inc(&totBufAllocCount);
174#endif /* CONFIG_CIFS_STATS2 */
175 }
176
177 return ret_buf;
178}
179
180void
181cifs_buf_release(void *buf_to_free)
182{
183 if (buf_to_free == NULL) {
184 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/
185 return;
186 }
187 mempool_free(buf_to_free, cifs_req_poolp);
188
189 atomic_dec(&bufAllocCount);
190 return;
191}
192
193struct smb_hdr *
194cifs_small_buf_get(void)
195{
196 struct smb_hdr *ret_buf = NULL;
197
198/* We could use negotiated size instead of max_msgsize -
199 but it may be more efficient to always alloc same size
200 albeit slightly larger than necessary and maxbuffersize
201 defaults to this and can not be bigger */
202 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
203 if (ret_buf) {
204 /* No need to clear memory here, cleared in header assemble */
205 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
206 atomic_inc(&smBufAllocCount);
207#ifdef CONFIG_CIFS_STATS2
208 atomic_inc(&totSmBufAllocCount);
209#endif /* CONFIG_CIFS_STATS2 */
210
211 }
212 return ret_buf;
213}
214
215void
216cifs_small_buf_release(void *buf_to_free)
217{
218
219 if (buf_to_free == NULL) {
220 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n");
221 return;
222 }
223 mempool_free(buf_to_free, cifs_sm_req_poolp);
224
225 atomic_dec(&smBufAllocCount);
226 return;
227}
228
229void
230free_rsp_buf(int resp_buftype, void *rsp)
231{
232 if (resp_buftype == CIFS_SMALL_BUFFER)
233 cifs_small_buf_release(rsp);
234 else if (resp_buftype == CIFS_LARGE_BUFFER)
235 cifs_buf_release(rsp);
236}
237
238/* NB: MID can not be set if treeCon not passed in, in that
239 case it is responsbility of caller to set the mid */
240void
241header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
242 const struct cifs_tcon *treeCon, int word_count
243 /* length of fixed section (word count) in two byte units */)
244{
245 char *temp = (char *) buffer;
246
247 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
248
249 buffer->smb_buf_length = cpu_to_be32(
250 (2 * word_count) + sizeof(struct smb_hdr) -
251 4 /* RFC 1001 length field does not count */ +
252 2 /* for bcc field itself */) ;
253
254 buffer->Protocol[0] = 0xFF;
255 buffer->Protocol[1] = 'S';
256 buffer->Protocol[2] = 'M';
257 buffer->Protocol[3] = 'B';
258 buffer->Command = smb_command;
259 buffer->Flags = 0x00; /* case sensitive */
260 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
261 buffer->Pid = cpu_to_le16((__u16)current->tgid);
262 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
263 if (treeCon) {
264 buffer->Tid = treeCon->tid;
265 if (treeCon->ses) {
266 if (treeCon->ses->capabilities & CAP_UNICODE)
267 buffer->Flags2 |= SMBFLG2_UNICODE;
268 if (treeCon->ses->capabilities & CAP_STATUS32)
269 buffer->Flags2 |= SMBFLG2_ERR_STATUS;
270
271 /* Uid is not converted */
272 buffer->Uid = treeCon->ses->Suid;
273 buffer->Mid = get_next_mid(treeCon->ses->server);
274 }
275 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
276 buffer->Flags2 |= SMBFLG2_DFS;
277 if (treeCon->nocase)
278 buffer->Flags |= SMBFLG_CASELESS;
279 if ((treeCon->ses) && (treeCon->ses->server))
280 if (treeCon->ses->server->sign)
281 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
282 }
283
284/* endian conversion of flags is now done just before sending */
285 buffer->WordCount = (char) word_count;
286 return;
287}
288
289static int
290check_smb_hdr(struct smb_hdr *smb)
291{
292 /* does it have the right SMB "signature" ? */
293 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
294 cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n",
295 *(unsigned int *)smb->Protocol);
296 return 1;
297 }
298
299 /* if it's a response then accept */
300 if (smb->Flags & SMBFLG_RESPONSE)
301 return 0;
302
303 /* only one valid case where server sends us request */
304 if (smb->Command == SMB_COM_LOCKING_ANDX)
305 return 0;
306
307 cifs_dbg(VFS, "Server sent request, not response. mid=%u\n",
308 get_mid(smb));
309 return 1;
310}
311
312int
313checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server)
314{
315 struct smb_hdr *smb = (struct smb_hdr *)buf;
316 __u32 rfclen = be32_to_cpu(smb->smb_buf_length);
317 __u32 clc_len; /* calculated length */
318 cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n",
319 total_read, rfclen);
320
321 /* is this frame too small to even get to a BCC? */
322 if (total_read < 2 + sizeof(struct smb_hdr)) {
323 if ((total_read >= sizeof(struct smb_hdr) - 1)
324 && (smb->Status.CifsError != 0)) {
325 /* it's an error return */
326 smb->WordCount = 0;
327 /* some error cases do not return wct and bcc */
328 return 0;
329 } else if ((total_read == sizeof(struct smb_hdr) + 1) &&
330 (smb->WordCount == 0)) {
331 char *tmp = (char *)smb;
332 /* Need to work around a bug in two servers here */
333 /* First, check if the part of bcc they sent was zero */
334 if (tmp[sizeof(struct smb_hdr)] == 0) {
335 /* some servers return only half of bcc
336 * on simple responses (wct, bcc both zero)
337 * in particular have seen this on
338 * ulogoffX and FindClose. This leaves
339 * one byte of bcc potentially unitialized
340 */
341 /* zero rest of bcc */
342 tmp[sizeof(struct smb_hdr)+1] = 0;
343 return 0;
344 }
345 cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n");
346 } else {
347 cifs_dbg(VFS, "Length less than smb header size\n");
348 }
349 return -EIO;
350 }
351
352 /* otherwise, there is enough to get to the BCC */
353 if (check_smb_hdr(smb))
354 return -EIO;
355 clc_len = smbCalcSize(smb);
356
357 if (4 + rfclen != total_read) {
358 cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n",
359 rfclen);
360 return -EIO;
361 }
362
363 if (4 + rfclen != clc_len) {
364 __u16 mid = get_mid(smb);
365 /* check if bcc wrapped around for large read responses */
366 if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {
367 /* check if lengths match mod 64K */
368 if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))
369 return 0; /* bcc wrapped */
370 }
371 cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n",
372 clc_len, 4 + rfclen, mid);
373
374 if (4 + rfclen < clc_len) {
375 cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n",
376 rfclen, mid);
377 return -EIO;
378 } else if (rfclen > clc_len + 512) {
379 /*
380 * Some servers (Windows XP in particular) send more
381 * data than the lengths in the SMB packet would
382 * indicate on certain calls (byte range locks and
383 * trans2 find first calls in particular). While the
384 * client can handle such a frame by ignoring the
385 * trailing data, we choose limit the amount of extra
386 * data to 512 bytes.
387 */
388 cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n",
389 rfclen, mid);
390 return -EIO;
391 }
392 }
393 return 0;
394}
395
396bool
397is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
398{
399 struct smb_hdr *buf = (struct smb_hdr *)buffer;
400 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
401 struct list_head *tmp, *tmp1, *tmp2;
402 struct cifs_ses *ses;
403 struct cifs_tcon *tcon;
404 struct cifsInodeInfo *pCifsInode;
405 struct cifsFileInfo *netfile;
406
407 cifs_dbg(FYI, "Checking for oplock break or dnotify response\n");
408 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
409 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
410 struct smb_com_transaction_change_notify_rsp *pSMBr =
411 (struct smb_com_transaction_change_notify_rsp *)buf;
412 struct file_notify_information *pnotify;
413 __u32 data_offset = 0;
414 if (get_bcc(buf) > sizeof(struct file_notify_information)) {
415 data_offset = le32_to_cpu(pSMBr->DataOffset);
416
417 pnotify = (struct file_notify_information *)
418 ((char *)&pSMBr->hdr.Protocol + data_offset);
419 cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n",
420 pnotify->FileName, pnotify->Action);
421 /* cifs_dump_mem("Rcvd notify Data: ",buf,
422 sizeof(struct smb_hdr)+60); */
423 return true;
424 }
425 if (pSMBr->hdr.Status.CifsError) {
426 cifs_dbg(FYI, "notify err 0x%x\n",
427 pSMBr->hdr.Status.CifsError);
428 return true;
429 }
430 return false;
431 }
432 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
433 return false;
434 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
435 /* no sense logging error on invalid handle on oplock
436 break - harmless race between close request and oplock
437 break response is expected from time to time writing out
438 large dirty files cached on the client */
439 if ((NT_STATUS_INVALID_HANDLE) ==
440 le32_to_cpu(pSMB->hdr.Status.CifsError)) {
441 cifs_dbg(FYI, "invalid handle on oplock break\n");
442 return true;
443 } else if (ERRbadfid ==
444 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
445 return true;
446 } else {
447 return false; /* on valid oplock brk we get "request" */
448 }
449 }
450 if (pSMB->hdr.WordCount != 8)
451 return false;
452
453 cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n",
454 pSMB->LockType, pSMB->OplockLevel);
455 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
456 return false;
457
458 /* look up tcon based on tid & uid */
459 spin_lock(&cifs_tcp_ses_lock);
460 list_for_each(tmp, &srv->smb_ses_list) {
461 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
462 list_for_each(tmp1, &ses->tcon_list) {
463 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
464 if (tcon->tid != buf->Tid)
465 continue;
466
467 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
468 spin_lock(&cifs_file_list_lock);
469 list_for_each(tmp2, &tcon->openFileList) {
470 netfile = list_entry(tmp2, struct cifsFileInfo,
471 tlist);
472 if (pSMB->Fid != netfile->fid.netfid)
473 continue;
474
475 cifs_dbg(FYI, "file id match, oplock break\n");
476 pCifsInode = CIFS_I(d_inode(netfile->dentry));
477
478 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
479 &pCifsInode->flags);
480
481 /*
482 * Set flag if the server downgrades the oplock
483 * to L2 else clear.
484 */
485 if (pSMB->OplockLevel)
486 set_bit(
487 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
488 &pCifsInode->flags);
489 else
490 clear_bit(
491 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
492 &pCifsInode->flags);
493
494 queue_work(cifsiod_wq,
495 &netfile->oplock_break);
496 netfile->oplock_break_cancelled = false;
497
498 spin_unlock(&cifs_file_list_lock);
499 spin_unlock(&cifs_tcp_ses_lock);
500 return true;
501 }
502 spin_unlock(&cifs_file_list_lock);
503 spin_unlock(&cifs_tcp_ses_lock);
504 cifs_dbg(FYI, "No matching file for oplock break\n");
505 return true;
506 }
507 }
508 spin_unlock(&cifs_tcp_ses_lock);
509 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
510 return true;
511}
512
513void
514dump_smb(void *buf, int smb_buf_length)
515{
516 if (traceSMB == 0)
517 return;
518
519 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf,
520 smb_buf_length, true);
521}
522
523void
524cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
525{
526 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
527 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
528 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s. This server doesn't seem to support them properly. Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n",
529 cifs_sb_master_tcon(cifs_sb)->treeName);
530 }
531}
532
533void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
534{
535 oplock &= 0xF;
536
537 if (oplock == OPLOCK_EXCLUSIVE) {
538 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG;
539 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",
540 &cinode->vfs_inode);
541 } else if (oplock == OPLOCK_READ) {
542 cinode->oplock = CIFS_CACHE_READ_FLG;
543 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",
544 &cinode->vfs_inode);
545 } else
546 cinode->oplock = 0;
547}
548
549/*
550 * We wait for oplock breaks to be processed before we attempt to perform
551 * writes.
552 */
553int cifs_get_writer(struct cifsInodeInfo *cinode)
554{
555 int rc;
556
557start:
558 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK,
559 TASK_KILLABLE);
560 if (rc)
561 return rc;
562
563 spin_lock(&cinode->writers_lock);
564 if (!cinode->writers)
565 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
566 cinode->writers++;
567 /* Check to see if we have started servicing an oplock break */
568 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) {
569 cinode->writers--;
570 if (cinode->writers == 0) {
571 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
572 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
573 }
574 spin_unlock(&cinode->writers_lock);
575 goto start;
576 }
577 spin_unlock(&cinode->writers_lock);
578 return 0;
579}
580
581void cifs_put_writer(struct cifsInodeInfo *cinode)
582{
583 spin_lock(&cinode->writers_lock);
584 cinode->writers--;
585 if (cinode->writers == 0) {
586 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
587 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
588 }
589 spin_unlock(&cinode->writers_lock);
590}
591
592void cifs_done_oplock_break(struct cifsInodeInfo *cinode)
593{
594 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
595 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK);
596}
597
598bool
599backup_cred(struct cifs_sb_info *cifs_sb)
600{
601 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {
602 if (uid_eq(cifs_sb->mnt_backupuid, current_fsuid()))
603 return true;
604 }
605 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {
606 if (in_group_p(cifs_sb->mnt_backupgid))
607 return true;
608 }
609
610 return false;
611}
612
613void
614cifs_del_pending_open(struct cifs_pending_open *open)
615{
616 spin_lock(&cifs_file_list_lock);
617 list_del(&open->olist);
618 spin_unlock(&cifs_file_list_lock);
619}
620
621void
622cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,
623 struct cifs_pending_open *open)
624{
625#ifdef CONFIG_CIFS_SMB2
626 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
627#endif
628 open->oplock = CIFS_OPLOCK_NO_CHANGE;
629 open->tlink = tlink;
630 fid->pending_open = open;
631 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens);
632}
633
634void
635cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink,
636 struct cifs_pending_open *open)
637{
638 spin_lock(&cifs_file_list_lock);
639 cifs_add_pending_open_locked(fid, tlink, open);
640 spin_unlock(&cifs_file_list_lock);
641}
1/*
2 * fs/cifs/misc.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/slab.h>
23#include <linux/ctype.h>
24#include <linux/mempool.h>
25#include "cifspdu.h"
26#include "cifsglob.h"
27#include "cifsproto.h"
28#include "cifs_debug.h"
29#include "smberr.h"
30#include "nterr.h"
31#include "cifs_unicode.h"
32
33extern mempool_t *cifs_sm_req_poolp;
34extern mempool_t *cifs_req_poolp;
35
36/* The xid serves as a useful identifier for each incoming vfs request,
37 in a similar way to the mid which is useful to track each sent smb,
38 and CurrentXid can also provide a running counter (although it
39 will eventually wrap past zero) of the total vfs operations handled
40 since the cifs fs was mounted */
41
42unsigned int
43_GetXid(void)
44{
45 unsigned int xid;
46
47 spin_lock(&GlobalMid_Lock);
48 GlobalTotalActiveXid++;
49
50 /* keep high water mark for number of simultaneous ops in filesystem */
51 if (GlobalTotalActiveXid > GlobalMaxActiveXid)
52 GlobalMaxActiveXid = GlobalTotalActiveXid;
53 if (GlobalTotalActiveXid > 65000)
54 cFYI(1, "warning: more than 65000 requests active");
55 xid = GlobalCurrentXid++;
56 spin_unlock(&GlobalMid_Lock);
57 return xid;
58}
59
60void
61_FreeXid(unsigned int xid)
62{
63 spin_lock(&GlobalMid_Lock);
64 /* if (GlobalTotalActiveXid == 0)
65 BUG(); */
66 GlobalTotalActiveXid--;
67 spin_unlock(&GlobalMid_Lock);
68}
69
70struct cifs_ses *
71sesInfoAlloc(void)
72{
73 struct cifs_ses *ret_buf;
74
75 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);
76 if (ret_buf) {
77 atomic_inc(&sesInfoAllocCount);
78 ret_buf->status = CifsNew;
79 ++ret_buf->ses_count;
80 INIT_LIST_HEAD(&ret_buf->smb_ses_list);
81 INIT_LIST_HEAD(&ret_buf->tcon_list);
82 mutex_init(&ret_buf->session_mutex);
83 }
84 return ret_buf;
85}
86
87void
88sesInfoFree(struct cifs_ses *buf_to_free)
89{
90 if (buf_to_free == NULL) {
91 cFYI(1, "Null buffer passed to sesInfoFree");
92 return;
93 }
94
95 atomic_dec(&sesInfoAllocCount);
96 kfree(buf_to_free->serverOS);
97 kfree(buf_to_free->serverDomain);
98 kfree(buf_to_free->serverNOS);
99 if (buf_to_free->password) {
100 memset(buf_to_free->password, 0, strlen(buf_to_free->password));
101 kfree(buf_to_free->password);
102 }
103 kfree(buf_to_free->user_name);
104 kfree(buf_to_free->domainName);
105 kfree(buf_to_free);
106}
107
108struct cifs_tcon *
109tconInfoAlloc(void)
110{
111 struct cifs_tcon *ret_buf;
112 ret_buf = kzalloc(sizeof(struct cifs_tcon), GFP_KERNEL);
113 if (ret_buf) {
114 atomic_inc(&tconInfoAllocCount);
115 ret_buf->tidStatus = CifsNew;
116 ++ret_buf->tc_count;
117 INIT_LIST_HEAD(&ret_buf->openFileList);
118 INIT_LIST_HEAD(&ret_buf->tcon_list);
119#ifdef CONFIG_CIFS_STATS
120 spin_lock_init(&ret_buf->stat_lock);
121#endif
122 }
123 return ret_buf;
124}
125
126void
127tconInfoFree(struct cifs_tcon *buf_to_free)
128{
129 if (buf_to_free == NULL) {
130 cFYI(1, "Null buffer passed to tconInfoFree");
131 return;
132 }
133 atomic_dec(&tconInfoAllocCount);
134 kfree(buf_to_free->nativeFileSystem);
135 if (buf_to_free->password) {
136 memset(buf_to_free->password, 0, strlen(buf_to_free->password));
137 kfree(buf_to_free->password);
138 }
139 kfree(buf_to_free);
140}
141
142struct smb_hdr *
143cifs_buf_get(void)
144{
145 struct smb_hdr *ret_buf = NULL;
146
147/* We could use negotiated size instead of max_msgsize -
148 but it may be more efficient to always alloc same size
149 albeit slightly larger than necessary and maxbuffersize
150 defaults to this and can not be bigger */
151 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
152
153 /* clear the first few header bytes */
154 /* for most paths, more is cleared in header_assemble */
155 if (ret_buf) {
156 memset(ret_buf, 0, sizeof(struct smb_hdr) + 3);
157 atomic_inc(&bufAllocCount);
158#ifdef CONFIG_CIFS_STATS2
159 atomic_inc(&totBufAllocCount);
160#endif /* CONFIG_CIFS_STATS2 */
161 }
162
163 return ret_buf;
164}
165
166void
167cifs_buf_release(void *buf_to_free)
168{
169 if (buf_to_free == NULL) {
170 /* cFYI(1, "Null buffer passed to cifs_buf_release");*/
171 return;
172 }
173 mempool_free(buf_to_free, cifs_req_poolp);
174
175 atomic_dec(&bufAllocCount);
176 return;
177}
178
179struct smb_hdr *
180cifs_small_buf_get(void)
181{
182 struct smb_hdr *ret_buf = NULL;
183
184/* We could use negotiated size instead of max_msgsize -
185 but it may be more efficient to always alloc same size
186 albeit slightly larger than necessary and maxbuffersize
187 defaults to this and can not be bigger */
188 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
189 if (ret_buf) {
190 /* No need to clear memory here, cleared in header assemble */
191 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
192 atomic_inc(&smBufAllocCount);
193#ifdef CONFIG_CIFS_STATS2
194 atomic_inc(&totSmBufAllocCount);
195#endif /* CONFIG_CIFS_STATS2 */
196
197 }
198 return ret_buf;
199}
200
201void
202cifs_small_buf_release(void *buf_to_free)
203{
204
205 if (buf_to_free == NULL) {
206 cFYI(1, "Null buffer passed to cifs_small_buf_release");
207 return;
208 }
209 mempool_free(buf_to_free, cifs_sm_req_poolp);
210
211 atomic_dec(&smBufAllocCount);
212 return;
213}
214
215/*
216 Find a free multiplex id (SMB mid). Otherwise there could be
217 mid collisions which might cause problems, demultiplexing the
218 wrong response to this request. Multiplex ids could collide if
219 one of a series requests takes much longer than the others, or
220 if a very large number of long lived requests (byte range
221 locks or FindNotify requests) are pending. No more than
222 64K-1 requests can be outstanding at one time. If no
223 mids are available, return zero. A future optimization
224 could make the combination of mids and uid the key we use
225 to demultiplex on (rather than mid alone).
226 In addition to the above check, the cifs demultiplex
227 code already used the command code as a secondary
228 check of the frame and if signing is negotiated the
229 response would be discarded if the mid were the same
230 but the signature was wrong. Since the mid is not put in the
231 pending queue until later (when it is about to be dispatched)
232 we do have to limit the number of outstanding requests
233 to somewhat less than 64K-1 although it is hard to imagine
234 so many threads being in the vfs at one time.
235*/
236__u16 GetNextMid(struct TCP_Server_Info *server)
237{
238 __u16 mid = 0;
239 __u16 last_mid;
240 bool collision;
241
242 spin_lock(&GlobalMid_Lock);
243 last_mid = server->CurrentMid; /* we do not want to loop forever */
244 server->CurrentMid++;
245 /* This nested loop looks more expensive than it is.
246 In practice the list of pending requests is short,
247 fewer than 50, and the mids are likely to be unique
248 on the first pass through the loop unless some request
249 takes longer than the 64 thousand requests before it
250 (and it would also have to have been a request that
251 did not time out) */
252 while (server->CurrentMid != last_mid) {
253 struct mid_q_entry *mid_entry;
254 unsigned int num_mids;
255
256 collision = false;
257 if (server->CurrentMid == 0)
258 server->CurrentMid++;
259
260 num_mids = 0;
261 list_for_each_entry(mid_entry, &server->pending_mid_q, qhead) {
262 ++num_mids;
263 if (mid_entry->mid == server->CurrentMid &&
264 mid_entry->midState == MID_REQUEST_SUBMITTED) {
265 /* This mid is in use, try a different one */
266 collision = true;
267 break;
268 }
269 }
270
271 /*
272 * if we have more than 32k mids in the list, then something
273 * is very wrong. Possibly a local user is trying to DoS the
274 * box by issuing long-running calls and SIGKILL'ing them. If
275 * we get to 2^16 mids then we're in big trouble as this
276 * function could loop forever.
277 *
278 * Go ahead and assign out the mid in this situation, but force
279 * an eventual reconnect to clean out the pending_mid_q.
280 */
281 if (num_mids > 32768)
282 server->tcpStatus = CifsNeedReconnect;
283
284 if (!collision) {
285 mid = server->CurrentMid;
286 break;
287 }
288 server->CurrentMid++;
289 }
290 spin_unlock(&GlobalMid_Lock);
291 return mid;
292}
293
294/* NB: MID can not be set if treeCon not passed in, in that
295 case it is responsbility of caller to set the mid */
296void
297header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
298 const struct cifs_tcon *treeCon, int word_count
299 /* length of fixed section (word count) in two byte units */)
300{
301 struct list_head *temp_item;
302 struct cifs_ses *ses;
303 char *temp = (char *) buffer;
304
305 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
306
307 buffer->smb_buf_length = cpu_to_be32(
308 (2 * word_count) + sizeof(struct smb_hdr) -
309 4 /* RFC 1001 length field does not count */ +
310 2 /* for bcc field itself */) ;
311
312 buffer->Protocol[0] = 0xFF;
313 buffer->Protocol[1] = 'S';
314 buffer->Protocol[2] = 'M';
315 buffer->Protocol[3] = 'B';
316 buffer->Command = smb_command;
317 buffer->Flags = 0x00; /* case sensitive */
318 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
319 buffer->Pid = cpu_to_le16((__u16)current->tgid);
320 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
321 if (treeCon) {
322 buffer->Tid = treeCon->tid;
323 if (treeCon->ses) {
324 if (treeCon->ses->capabilities & CAP_UNICODE)
325 buffer->Flags2 |= SMBFLG2_UNICODE;
326 if (treeCon->ses->capabilities & CAP_STATUS32)
327 buffer->Flags2 |= SMBFLG2_ERR_STATUS;
328
329 /* Uid is not converted */
330 buffer->Uid = treeCon->ses->Suid;
331 buffer->Mid = GetNextMid(treeCon->ses->server);
332 if (multiuser_mount != 0) {
333 /* For the multiuser case, there are few obvious technically */
334 /* possible mechanisms to match the local linux user (uid) */
335 /* to a valid remote smb user (smb_uid): */
336 /* 1) Query Winbind (or other local pam/nss daemon */
337 /* for userid/password/logon_domain or credential */
338 /* 2) Query Winbind for uid to sid to username mapping */
339 /* and see if we have a matching password for existing*/
340 /* session for that user perhas getting password by */
341 /* adding a new pam_cifs module that stores passwords */
342 /* so that the cifs vfs can get at that for all logged*/
343 /* on users */
344 /* 3) (Which is the mechanism we have chosen) */
345 /* Search through sessions to the same server for a */
346 /* a match on the uid that was passed in on mount */
347 /* with the current processes uid (or euid?) and use */
348 /* that smb uid. If no existing smb session for */
349 /* that uid found, use the default smb session ie */
350 /* the smb session for the volume mounted which is */
351 /* the same as would be used if the multiuser mount */
352 /* flag were disabled. */
353
354 /* BB Add support for establishing new tCon and SMB Session */
355 /* with userid/password pairs found on the smb session */
356 /* for other target tcp/ip addresses BB */
357 if (current_fsuid() != treeCon->ses->linux_uid) {
358 cFYI(1, "Multiuser mode and UID "
359 "did not match tcon uid");
360 spin_lock(&cifs_tcp_ses_lock);
361 list_for_each(temp_item, &treeCon->ses->server->smb_ses_list) {
362 ses = list_entry(temp_item, struct cifs_ses, smb_ses_list);
363 if (ses->linux_uid == current_fsuid()) {
364 if (ses->server == treeCon->ses->server) {
365 cFYI(1, "found matching uid substitute right smb_uid");
366 buffer->Uid = ses->Suid;
367 break;
368 } else {
369 /* BB eventually call cifs_setup_session here */
370 cFYI(1, "local UID found but no smb sess with this server exists");
371 }
372 }
373 }
374 spin_unlock(&cifs_tcp_ses_lock);
375 }
376 }
377 }
378 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
379 buffer->Flags2 |= SMBFLG2_DFS;
380 if (treeCon->nocase)
381 buffer->Flags |= SMBFLG_CASELESS;
382 if ((treeCon->ses) && (treeCon->ses->server))
383 if (treeCon->ses->server->sec_mode &
384 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
385 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
386 }
387
388/* endian conversion of flags is now done just before sending */
389 buffer->WordCount = (char) word_count;
390 return;
391}
392
393static int
394check_smb_hdr(struct smb_hdr *smb, __u16 mid)
395{
396 /* does it have the right SMB "signature" ? */
397 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
398 cERROR(1, "Bad protocol string signature header 0x%x",
399 *(unsigned int *)smb->Protocol);
400 return 1;
401 }
402
403 /* Make sure that message ids match */
404 if (mid != smb->Mid) {
405 cERROR(1, "Mids do not match. received=%u expected=%u",
406 smb->Mid, mid);
407 return 1;
408 }
409
410 /* if it's a response then accept */
411 if (smb->Flags & SMBFLG_RESPONSE)
412 return 0;
413
414 /* only one valid case where server sends us request */
415 if (smb->Command == SMB_COM_LOCKING_ANDX)
416 return 0;
417
418 cERROR(1, "Server sent request, not response. mid=%u", smb->Mid);
419 return 1;
420}
421
422int
423checkSMB(struct smb_hdr *smb, __u16 mid, unsigned int length)
424{
425 __u32 len = be32_to_cpu(smb->smb_buf_length);
426 __u32 clc_len; /* calculated length */
427 cFYI(0, "checkSMB Length: 0x%x, smb_buf_length: 0x%x", length, len);
428
429 if (length < 2 + sizeof(struct smb_hdr)) {
430 if ((length >= sizeof(struct smb_hdr) - 1)
431 && (smb->Status.CifsError != 0)) {
432 smb->WordCount = 0;
433 /* some error cases do not return wct and bcc */
434 return 0;
435 } else if ((length == sizeof(struct smb_hdr) + 1) &&
436 (smb->WordCount == 0)) {
437 char *tmp = (char *)smb;
438 /* Need to work around a bug in two servers here */
439 /* First, check if the part of bcc they sent was zero */
440 if (tmp[sizeof(struct smb_hdr)] == 0) {
441 /* some servers return only half of bcc
442 * on simple responses (wct, bcc both zero)
443 * in particular have seen this on
444 * ulogoffX and FindClose. This leaves
445 * one byte of bcc potentially unitialized
446 */
447 /* zero rest of bcc */
448 tmp[sizeof(struct smb_hdr)+1] = 0;
449 return 0;
450 }
451 cERROR(1, "rcvd invalid byte count (bcc)");
452 } else {
453 cERROR(1, "Length less than smb header size");
454 }
455 return 1;
456 }
457 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
458 cERROR(1, "smb length greater than MaxBufSize, mid=%d",
459 smb->Mid);
460 return 1;
461 }
462
463 if (check_smb_hdr(smb, mid))
464 return 1;
465 clc_len = smbCalcSize(smb);
466
467 if (4 + len != length) {
468 cERROR(1, "Length read does not match RFC1001 length %d",
469 len);
470 return 1;
471 }
472
473 if (4 + len != clc_len) {
474 /* check if bcc wrapped around for large read responses */
475 if ((len > 64 * 1024) && (len > clc_len)) {
476 /* check if lengths match mod 64K */
477 if (((4 + len) & 0xFFFF) == (clc_len & 0xFFFF))
478 return 0; /* bcc wrapped */
479 }
480 cFYI(1, "Calculated size %u vs length %u mismatch for mid=%u",
481 clc_len, 4 + len, smb->Mid);
482
483 if (4 + len < clc_len) {
484 cERROR(1, "RFC1001 size %u smaller than SMB for mid=%u",
485 len, smb->Mid);
486 return 1;
487 } else if (len > clc_len + 512) {
488 /*
489 * Some servers (Windows XP in particular) send more
490 * data than the lengths in the SMB packet would
491 * indicate on certain calls (byte range locks and
492 * trans2 find first calls in particular). While the
493 * client can handle such a frame by ignoring the
494 * trailing data, we choose limit the amount of extra
495 * data to 512 bytes.
496 */
497 cERROR(1, "RFC1001 size %u more than 512 bytes larger "
498 "than SMB for mid=%u", len, smb->Mid);
499 return 1;
500 }
501 }
502 return 0;
503}
504
505bool
506is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
507{
508 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
509 struct list_head *tmp, *tmp1, *tmp2;
510 struct cifs_ses *ses;
511 struct cifs_tcon *tcon;
512 struct cifsInodeInfo *pCifsInode;
513 struct cifsFileInfo *netfile;
514
515 cFYI(1, "Checking for oplock break or dnotify response");
516 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
517 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
518 struct smb_com_transaction_change_notify_rsp *pSMBr =
519 (struct smb_com_transaction_change_notify_rsp *)buf;
520 struct file_notify_information *pnotify;
521 __u32 data_offset = 0;
522 if (get_bcc(buf) > sizeof(struct file_notify_information)) {
523 data_offset = le32_to_cpu(pSMBr->DataOffset);
524
525 pnotify = (struct file_notify_information *)
526 ((char *)&pSMBr->hdr.Protocol + data_offset);
527 cFYI(1, "dnotify on %s Action: 0x%x",
528 pnotify->FileName, pnotify->Action);
529 /* cifs_dump_mem("Rcvd notify Data: ",buf,
530 sizeof(struct smb_hdr)+60); */
531 return true;
532 }
533 if (pSMBr->hdr.Status.CifsError) {
534 cFYI(1, "notify err 0x%d",
535 pSMBr->hdr.Status.CifsError);
536 return true;
537 }
538 return false;
539 }
540 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
541 return false;
542 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
543 /* no sense logging error on invalid handle on oplock
544 break - harmless race between close request and oplock
545 break response is expected from time to time writing out
546 large dirty files cached on the client */
547 if ((NT_STATUS_INVALID_HANDLE) ==
548 le32_to_cpu(pSMB->hdr.Status.CifsError)) {
549 cFYI(1, "invalid handle on oplock break");
550 return true;
551 } else if (ERRbadfid ==
552 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
553 return true;
554 } else {
555 return false; /* on valid oplock brk we get "request" */
556 }
557 }
558 if (pSMB->hdr.WordCount != 8)
559 return false;
560
561 cFYI(1, "oplock type 0x%d level 0x%d",
562 pSMB->LockType, pSMB->OplockLevel);
563 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
564 return false;
565
566 /* look up tcon based on tid & uid */
567 spin_lock(&cifs_tcp_ses_lock);
568 list_for_each(tmp, &srv->smb_ses_list) {
569 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
570 list_for_each(tmp1, &ses->tcon_list) {
571 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
572 if (tcon->tid != buf->Tid)
573 continue;
574
575 cifs_stats_inc(&tcon->num_oplock_brks);
576 spin_lock(&cifs_file_list_lock);
577 list_for_each(tmp2, &tcon->openFileList) {
578 netfile = list_entry(tmp2, struct cifsFileInfo,
579 tlist);
580 if (pSMB->Fid != netfile->netfid)
581 continue;
582
583 cFYI(1, "file id match, oplock break");
584 pCifsInode = CIFS_I(netfile->dentry->d_inode);
585
586 cifs_set_oplock_level(pCifsInode,
587 pSMB->OplockLevel ? OPLOCK_READ : 0);
588 queue_work(system_nrt_wq,
589 &netfile->oplock_break);
590 netfile->oplock_break_cancelled = false;
591
592 spin_unlock(&cifs_file_list_lock);
593 spin_unlock(&cifs_tcp_ses_lock);
594 return true;
595 }
596 spin_unlock(&cifs_file_list_lock);
597 spin_unlock(&cifs_tcp_ses_lock);
598 cFYI(1, "No matching file for oplock break");
599 return true;
600 }
601 }
602 spin_unlock(&cifs_tcp_ses_lock);
603 cFYI(1, "Can not process oplock break for non-existent connection");
604 return true;
605}
606
607void
608dump_smb(struct smb_hdr *smb_buf, int smb_buf_length)
609{
610 int i, j;
611 char debug_line[17];
612 unsigned char *buffer;
613
614 if (traceSMB == 0)
615 return;
616
617 buffer = (unsigned char *) smb_buf;
618 for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
619 if (i % 8 == 0) {
620 /* have reached the beginning of line */
621 printk(KERN_DEBUG "| ");
622 j = 0;
623 }
624 printk("%0#4x ", buffer[i]);
625 debug_line[2 * j] = ' ';
626 if (isprint(buffer[i]))
627 debug_line[1 + (2 * j)] = buffer[i];
628 else
629 debug_line[1 + (2 * j)] = '_';
630
631 if (i % 8 == 7) {
632 /* reached end of line, time to print ascii */
633 debug_line[16] = 0;
634 printk(" | %s\n", debug_line);
635 }
636 }
637 for (; j < 8; j++) {
638 printk(" ");
639 debug_line[2 * j] = ' ';
640 debug_line[1 + (2 * j)] = ' ';
641 }
642 printk(" | %s\n", debug_line);
643 return;
644}
645
646void
647cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
648{
649 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
650 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
651 cERROR(1, "Autodisabling the use of server inode numbers on "
652 "%s. This server doesn't seem to support them "
653 "properly. Hardlinks will not be recognized on this "
654 "mount. Consider mounting with the \"noserverino\" "
655 "option to silence this message.",
656 cifs_sb_master_tcon(cifs_sb)->treeName);
657 }
658}
659
660void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
661{
662 oplock &= 0xF;
663
664 if (oplock == OPLOCK_EXCLUSIVE) {
665 cinode->clientCanCacheAll = true;
666 cinode->clientCanCacheRead = true;
667 cFYI(1, "Exclusive Oplock granted on inode %p",
668 &cinode->vfs_inode);
669 } else if (oplock == OPLOCK_READ) {
670 cinode->clientCanCacheAll = false;
671 cinode->clientCanCacheRead = true;
672 cFYI(1, "Level II Oplock granted on inode %p",
673 &cinode->vfs_inode);
674 } else {
675 cinode->clientCanCacheAll = false;
676 cinode->clientCanCacheRead = false;
677 }
678}