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v4.6
  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}
v3.15
  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
 
 
 
 
 
 
 
 
 
229/* NB: MID can not be set if treeCon not passed in, in that
230   case it is responsbility of caller to set the mid */
231void
232header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
233		const struct cifs_tcon *treeCon, int word_count
234		/* length of fixed section (word count) in two byte units  */)
235{
236	char *temp = (char *) buffer;
237
238	memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
239
240	buffer->smb_buf_length = cpu_to_be32(
241	    (2 * word_count) + sizeof(struct smb_hdr) -
242	    4 /*  RFC 1001 length field does not count */  +
243	    2 /* for bcc field itself */) ;
244
245	buffer->Protocol[0] = 0xFF;
246	buffer->Protocol[1] = 'S';
247	buffer->Protocol[2] = 'M';
248	buffer->Protocol[3] = 'B';
249	buffer->Command = smb_command;
250	buffer->Flags = 0x00;	/* case sensitive */
251	buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
252	buffer->Pid = cpu_to_le16((__u16)current->tgid);
253	buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
254	if (treeCon) {
255		buffer->Tid = treeCon->tid;
256		if (treeCon->ses) {
257			if (treeCon->ses->capabilities & CAP_UNICODE)
258				buffer->Flags2 |= SMBFLG2_UNICODE;
259			if (treeCon->ses->capabilities & CAP_STATUS32)
260				buffer->Flags2 |= SMBFLG2_ERR_STATUS;
261
262			/* Uid is not converted */
263			buffer->Uid = treeCon->ses->Suid;
264			buffer->Mid = get_next_mid(treeCon->ses->server);
265		}
266		if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
267			buffer->Flags2 |= SMBFLG2_DFS;
268		if (treeCon->nocase)
269			buffer->Flags  |= SMBFLG_CASELESS;
270		if ((treeCon->ses) && (treeCon->ses->server))
271			if (treeCon->ses->server->sign)
272				buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
273	}
274
275/*  endian conversion of flags is now done just before sending */
276	buffer->WordCount = (char) word_count;
277	return;
278}
279
280static int
281check_smb_hdr(struct smb_hdr *smb)
282{
283	/* does it have the right SMB "signature" ? */
284	if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
285		cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n",
286			 *(unsigned int *)smb->Protocol);
287		return 1;
288	}
289
290	/* if it's a response then accept */
291	if (smb->Flags & SMBFLG_RESPONSE)
292		return 0;
293
294	/* only one valid case where server sends us request */
295	if (smb->Command == SMB_COM_LOCKING_ANDX)
296		return 0;
297
298	cifs_dbg(VFS, "Server sent request, not response. mid=%u\n",
299		 get_mid(smb));
300	return 1;
301}
302
303int
304checkSMB(char *buf, unsigned int total_read)
305{
306	struct smb_hdr *smb = (struct smb_hdr *)buf;
307	__u32 rfclen = be32_to_cpu(smb->smb_buf_length);
308	__u32 clc_len;  /* calculated length */
309	cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n",
310		 total_read, rfclen);
311
312	/* is this frame too small to even get to a BCC? */
313	if (total_read < 2 + sizeof(struct smb_hdr)) {
314		if ((total_read >= sizeof(struct smb_hdr) - 1)
315			    && (smb->Status.CifsError != 0)) {
316			/* it's an error return */
317			smb->WordCount = 0;
318			/* some error cases do not return wct and bcc */
319			return 0;
320		} else if ((total_read == sizeof(struct smb_hdr) + 1) &&
321				(smb->WordCount == 0)) {
322			char *tmp = (char *)smb;
323			/* Need to work around a bug in two servers here */
324			/* First, check if the part of bcc they sent was zero */
325			if (tmp[sizeof(struct smb_hdr)] == 0) {
326				/* some servers return only half of bcc
327				 * on simple responses (wct, bcc both zero)
328				 * in particular have seen this on
329				 * ulogoffX and FindClose. This leaves
330				 * one byte of bcc potentially unitialized
331				 */
332				/* zero rest of bcc */
333				tmp[sizeof(struct smb_hdr)+1] = 0;
334				return 0;
335			}
336			cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n");
337		} else {
338			cifs_dbg(VFS, "Length less than smb header size\n");
339		}
340		return -EIO;
341	}
342
343	/* otherwise, there is enough to get to the BCC */
344	if (check_smb_hdr(smb))
345		return -EIO;
346	clc_len = smbCalcSize(smb);
347
348	if (4 + rfclen != total_read) {
349		cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n",
350			 rfclen);
351		return -EIO;
352	}
353
354	if (4 + rfclen != clc_len) {
355		__u16 mid = get_mid(smb);
356		/* check if bcc wrapped around for large read responses */
357		if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {
358			/* check if lengths match mod 64K */
359			if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))
360				return 0; /* bcc wrapped */
361		}
362		cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n",
363			 clc_len, 4 + rfclen, mid);
364
365		if (4 + rfclen < clc_len) {
366			cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n",
367				 rfclen, mid);
368			return -EIO;
369		} else if (rfclen > clc_len + 512) {
370			/*
371			 * Some servers (Windows XP in particular) send more
372			 * data than the lengths in the SMB packet would
373			 * indicate on certain calls (byte range locks and
374			 * trans2 find first calls in particular). While the
375			 * client can handle such a frame by ignoring the
376			 * trailing data, we choose limit the amount of extra
377			 * data to 512 bytes.
378			 */
379			cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n",
380				 rfclen, mid);
381			return -EIO;
382		}
383	}
384	return 0;
385}
386
387bool
388is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
389{
390	struct smb_hdr *buf = (struct smb_hdr *)buffer;
391	struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
392	struct list_head *tmp, *tmp1, *tmp2;
393	struct cifs_ses *ses;
394	struct cifs_tcon *tcon;
395	struct cifsInodeInfo *pCifsInode;
396	struct cifsFileInfo *netfile;
397
398	cifs_dbg(FYI, "Checking for oplock break or dnotify response\n");
399	if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
400	   (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
401		struct smb_com_transaction_change_notify_rsp *pSMBr =
402			(struct smb_com_transaction_change_notify_rsp *)buf;
403		struct file_notify_information *pnotify;
404		__u32 data_offset = 0;
405		if (get_bcc(buf) > sizeof(struct file_notify_information)) {
406			data_offset = le32_to_cpu(pSMBr->DataOffset);
407
408			pnotify = (struct file_notify_information *)
409				((char *)&pSMBr->hdr.Protocol + data_offset);
410			cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n",
411				 pnotify->FileName, pnotify->Action);
412			/*   cifs_dump_mem("Rcvd notify Data: ",buf,
413				sizeof(struct smb_hdr)+60); */
414			return true;
415		}
416		if (pSMBr->hdr.Status.CifsError) {
417			cifs_dbg(FYI, "notify err 0x%d\n",
418				 pSMBr->hdr.Status.CifsError);
419			return true;
420		}
421		return false;
422	}
423	if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
424		return false;
425	if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
426		/* no sense logging error on invalid handle on oplock
427		   break - harmless race between close request and oplock
428		   break response is expected from time to time writing out
429		   large dirty files cached on the client */
430		if ((NT_STATUS_INVALID_HANDLE) ==
431		   le32_to_cpu(pSMB->hdr.Status.CifsError)) {
432			cifs_dbg(FYI, "invalid handle on oplock break\n");
433			return true;
434		} else if (ERRbadfid ==
435		   le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
436			return true;
437		} else {
438			return false; /* on valid oplock brk we get "request" */
439		}
440	}
441	if (pSMB->hdr.WordCount != 8)
442		return false;
443
444	cifs_dbg(FYI, "oplock type 0x%d level 0x%d\n",
445		 pSMB->LockType, pSMB->OplockLevel);
446	if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
447		return false;
448
449	/* look up tcon based on tid & uid */
450	spin_lock(&cifs_tcp_ses_lock);
451	list_for_each(tmp, &srv->smb_ses_list) {
452		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
453		list_for_each(tmp1, &ses->tcon_list) {
454			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
455			if (tcon->tid != buf->Tid)
456				continue;
457
458			cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
459			spin_lock(&cifs_file_list_lock);
460			list_for_each(tmp2, &tcon->openFileList) {
461				netfile = list_entry(tmp2, struct cifsFileInfo,
462						     tlist);
463				if (pSMB->Fid != netfile->fid.netfid)
464					continue;
465
466				cifs_dbg(FYI, "file id match, oplock break\n");
467				pCifsInode = CIFS_I(netfile->dentry->d_inode);
468
469				set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
470					&pCifsInode->flags);
471
472				/*
473				 * Set flag if the server downgrades the oplock
474				 * to L2 else clear.
475				 */
476				if (pSMB->OplockLevel)
477					set_bit(
478					   CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
479					   &pCifsInode->flags);
480				else
481					clear_bit(
482					   CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
483					   &pCifsInode->flags);
484
485				queue_work(cifsiod_wq,
486					   &netfile->oplock_break);
487				netfile->oplock_break_cancelled = false;
488
489				spin_unlock(&cifs_file_list_lock);
490				spin_unlock(&cifs_tcp_ses_lock);
491				return true;
492			}
493			spin_unlock(&cifs_file_list_lock);
494			spin_unlock(&cifs_tcp_ses_lock);
495			cifs_dbg(FYI, "No matching file for oplock break\n");
496			return true;
497		}
498	}
499	spin_unlock(&cifs_tcp_ses_lock);
500	cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
501	return true;
502}
503
504void
505dump_smb(void *buf, int smb_buf_length)
506{
507	int i, j;
508	char debug_line[17];
509	unsigned char *buffer = buf;
510
511	if (traceSMB == 0)
512		return;
513
514	for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
515		if (i % 8 == 0) {
516			/* have reached the beginning of line */
517			printk(KERN_DEBUG "| ");
518			j = 0;
519		}
520		printk("%0#4x ", buffer[i]);
521		debug_line[2 * j] = ' ';
522		if (isprint(buffer[i]))
523			debug_line[1 + (2 * j)] = buffer[i];
524		else
525			debug_line[1 + (2 * j)] = '_';
526
527		if (i % 8 == 7) {
528			/* reached end of line, time to print ascii */
529			debug_line[16] = 0;
530			printk(" | %s\n", debug_line);
531		}
532	}
533	for (; j < 8; j++) {
534		printk("     ");
535		debug_line[2 * j] = ' ';
536		debug_line[1 + (2 * j)] = ' ';
537	}
538	printk(" | %s\n", debug_line);
539	return;
540}
541
542void
543cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
544{
545	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
546		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
547		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",
548			 cifs_sb_master_tcon(cifs_sb)->treeName);
549	}
550}
551
552void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
553{
554	oplock &= 0xF;
555
556	if (oplock == OPLOCK_EXCLUSIVE) {
557		cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG;
558		cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",
559			 &cinode->vfs_inode);
560	} else if (oplock == OPLOCK_READ) {
561		cinode->oplock = CIFS_CACHE_READ_FLG;
562		cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",
563			 &cinode->vfs_inode);
564	} else
565		cinode->oplock = 0;
566}
567
568static int
569cifs_oplock_break_wait(void *unused)
570{
571	schedule();
572	return signal_pending(current) ? -ERESTARTSYS : 0;
573}
574
575/*
576 * We wait for oplock breaks to be processed before we attempt to perform
577 * writes.
578 */
579int cifs_get_writer(struct cifsInodeInfo *cinode)
580{
581	int rc;
582
583start:
584	rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK,
585				   cifs_oplock_break_wait, TASK_KILLABLE);
586	if (rc)
587		return rc;
588
589	spin_lock(&cinode->writers_lock);
590	if (!cinode->writers)
591		set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
592	cinode->writers++;
593	/* Check to see if we have started servicing an oplock break */
594	if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) {
595		cinode->writers--;
596		if (cinode->writers == 0) {
597			clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
598			wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
599		}
600		spin_unlock(&cinode->writers_lock);
601		goto start;
602	}
603	spin_unlock(&cinode->writers_lock);
604	return 0;
605}
606
607void cifs_put_writer(struct cifsInodeInfo *cinode)
608{
609	spin_lock(&cinode->writers_lock);
610	cinode->writers--;
611	if (cinode->writers == 0) {
612		clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
613		wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
614	}
615	spin_unlock(&cinode->writers_lock);
616}
617
618void cifs_done_oplock_break(struct cifsInodeInfo *cinode)
619{
620	clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
621	wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK);
622}
623
624bool
625backup_cred(struct cifs_sb_info *cifs_sb)
626{
627	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {
628		if (uid_eq(cifs_sb->mnt_backupuid, current_fsuid()))
629			return true;
630	}
631	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {
632		if (in_group_p(cifs_sb->mnt_backupgid))
633			return true;
634	}
635
636	return false;
637}
638
639void
640cifs_del_pending_open(struct cifs_pending_open *open)
641{
642	spin_lock(&cifs_file_list_lock);
643	list_del(&open->olist);
644	spin_unlock(&cifs_file_list_lock);
645}
646
647void
648cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,
649			     struct cifs_pending_open *open)
650{
651#ifdef CONFIG_CIFS_SMB2
652	memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
653#endif
654	open->oplock = CIFS_OPLOCK_NO_CHANGE;
655	open->tlink = tlink;
656	fid->pending_open = open;
657	list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens);
658}
659
660void
661cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink,
662		      struct cifs_pending_open *open)
663{
664	spin_lock(&cifs_file_list_lock);
665	cifs_add_pending_open_locked(fid, tlink, open);
666	spin_unlock(&cifs_file_list_lock);
667}