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TOMOYO Linux Cross Reference
Linux/fs/cifs/misc.c

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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 
 36 extern mempool_t *cifs_sm_req_poolp;
 37 extern 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 
 45 unsigned 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 
 63 void
 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 
 73 struct cifs_ses *
 74 sesInfoAlloc(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 
 90 void
 91 sesInfoFree(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 
112 struct cifs_tcon *
113 tconInfoAlloc(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 
130 void
131 tconInfoFree(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 
146 struct smb_hdr *
147 cifs_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 
180 void
181 cifs_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 
193 struct smb_hdr *
194 cifs_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 
215 void
216 cifs_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 
229 void
230 free_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 */
240 void
241 header_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 
289 static int
290 check_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 
312 int
313 checkSMB(char *buf, unsigned int total_read)
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 
396 bool
397 is_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 
513 void
514 dump_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 
523 void
524 cifs_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 
533 void 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  */
553 int cifs_get_writer(struct cifsInodeInfo *cinode)
554 {
555         int rc;
556 
557 start:
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 
581 void 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 
592 void 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 
598 bool
599 backup_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 
613 void
614 cifs_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 
621 void
622 cifs_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 
634 void
635 cifs_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 }
642 

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