misc.c 21.0 KB
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/*
 *   fs/cifs/misc.c
 *
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 *   Copyright (C) International Business Machines  Corp., 2002,2008
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 *   Author(s): Steve French (sfrench@us.ibm.com)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
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 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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 */

#include <linux/slab.h>
#include <linux/ctype.h>
#include <linux/mempool.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "smberr.h"
#include "nterr.h"
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#include "cifs_unicode.h"
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extern mempool_t *cifs_sm_req_poolp;
extern mempool_t *cifs_req_poolp;

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/* The xid serves as a useful identifier for each incoming vfs request,
   in a similar way to the mid which is useful to track each sent smb,
   and CurrentXid can also provide a running counter (although it
   will eventually wrap past zero) of the total vfs operations handled
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   since the cifs fs was mounted */

unsigned int
_GetXid(void)
{
	unsigned int xid;

	spin_lock(&GlobalMid_Lock);
	GlobalTotalActiveXid++;
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	/* keep high water mark for number of simultaneous ops in filesystem */
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	if (GlobalTotalActiveXid > GlobalMaxActiveXid)
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		GlobalMaxActiveXid = GlobalTotalActiveXid;
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	if (GlobalTotalActiveXid > 65000)
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		cFYI(1, "warning: more than 65000 requests active");
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	xid = GlobalCurrentXid++;
	spin_unlock(&GlobalMid_Lock);
	return xid;
}

void
_FreeXid(unsigned int xid)
{
	spin_lock(&GlobalMid_Lock);
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	/* if (GlobalTotalActiveXid == 0)
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		BUG(); */
	GlobalTotalActiveXid--;
	spin_unlock(&GlobalMid_Lock);
}

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struct cifs_ses *
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sesInfoAlloc(void)
{
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	struct cifs_ses *ret_buf;
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	ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);
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	if (ret_buf) {
		atomic_inc(&sesInfoAllocCount);
		ret_buf->status = CifsNew;
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		++ret_buf->ses_count;
		INIT_LIST_HEAD(&ret_buf->smb_ses_list);
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		INIT_LIST_HEAD(&ret_buf->tcon_list);
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		mutex_init(&ret_buf->session_mutex);
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	}
	return ret_buf;
}

void
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sesInfoFree(struct cifs_ses *buf_to_free)
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{
	if (buf_to_free == NULL) {
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		cFYI(1, "Null buffer passed to sesInfoFree");
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		return;
	}

	atomic_dec(&sesInfoAllocCount);
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	kfree(buf_to_free->serverOS);
	kfree(buf_to_free->serverDomain);
	kfree(buf_to_free->serverNOS);
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	if (buf_to_free->password) {
		memset(buf_to_free->password, 0, strlen(buf_to_free->password));
		kfree(buf_to_free->password);
	}
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	kfree(buf_to_free->user_name);
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	kfree(buf_to_free->domainName);
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	kfree(buf_to_free);
}

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struct cifs_tcon *
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tconInfoAlloc(void)
{
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	struct cifs_tcon *ret_buf;
	ret_buf = kzalloc(sizeof(struct cifs_tcon), GFP_KERNEL);
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	if (ret_buf) {
		atomic_inc(&tconInfoAllocCount);
		ret_buf->tidStatus = CifsNew;
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		++ret_buf->tc_count;
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		INIT_LIST_HEAD(&ret_buf->openFileList);
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		INIT_LIST_HEAD(&ret_buf->tcon_list);
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#ifdef CONFIG_CIFS_STATS
		spin_lock_init(&ret_buf->stat_lock);
#endif
	}
	return ret_buf;
}

void
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tconInfoFree(struct cifs_tcon *buf_to_free)
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{
	if (buf_to_free == NULL) {
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		cFYI(1, "Null buffer passed to tconInfoFree");
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		return;
	}
	atomic_dec(&tconInfoAllocCount);
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	kfree(buf_to_free->nativeFileSystem);
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	if (buf_to_free->password) {
		memset(buf_to_free->password, 0, strlen(buf_to_free->password));
		kfree(buf_to_free->password);
	}
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	kfree(buf_to_free);
}

struct smb_hdr *
cifs_buf_get(void)
{
	struct smb_hdr *ret_buf = NULL;

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/* We could use negotiated size instead of max_msgsize -
   but it may be more efficient to always alloc same size
   albeit slightly larger than necessary and maxbuffersize
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   defaults to this and can not be bigger */
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	ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
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	/* clear the first few header bytes */
	/* for most paths, more is cleared in header_assemble */
	if (ret_buf) {
		memset(ret_buf, 0, sizeof(struct smb_hdr) + 3);
		atomic_inc(&bufAllocCount);
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#ifdef CONFIG_CIFS_STATS2
		atomic_inc(&totBufAllocCount);
#endif /* CONFIG_CIFS_STATS2 */
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	}

	return ret_buf;
}

void
cifs_buf_release(void *buf_to_free)
{
	if (buf_to_free == NULL) {
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		/* cFYI(1, "Null buffer passed to cifs_buf_release");*/
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		return;
	}
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	mempool_free(buf_to_free, cifs_req_poolp);
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	atomic_dec(&bufAllocCount);
	return;
}

struct smb_hdr *
cifs_small_buf_get(void)
{
	struct smb_hdr *ret_buf = NULL;

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/* We could use negotiated size instead of max_msgsize -
   but it may be more efficient to always alloc same size
   albeit slightly larger than necessary and maxbuffersize
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   defaults to this and can not be bigger */
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	ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
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	if (ret_buf) {
	/* No need to clear memory here, cleared in header assemble */
	/*	memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
		atomic_inc(&smBufAllocCount);
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#ifdef CONFIG_CIFS_STATS2
		atomic_inc(&totSmBufAllocCount);
#endif /* CONFIG_CIFS_STATS2 */

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	}
	return ret_buf;
}

void
cifs_small_buf_release(void *buf_to_free)
{

	if (buf_to_free == NULL) {
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		cFYI(1, "Null buffer passed to cifs_small_buf_release");
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		return;
	}
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	mempool_free(buf_to_free, cifs_sm_req_poolp);
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	atomic_dec(&smBufAllocCount);
	return;
}

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/*
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 * Find a free multiplex id (SMB mid). Otherwise there could be
 * mid collisions which might cause problems, demultiplexing the
 * wrong response to this request. Multiplex ids could collide if
 * one of a series requests takes much longer than the others, or
 * if a very large number of long lived requests (byte range
 * locks or FindNotify requests) are pending. No more than
 * 64K-1 requests can be outstanding at one time. If no
 * mids are available, return zero. A future optimization
 * could make the combination of mids and uid the key we use
 * to demultiplex on (rather than mid alone).
 * In addition to the above check, the cifs demultiplex
 * code already used the command code as a secondary
 * check of the frame and if signing is negotiated the
 * response would be discarded if the mid were the same
 * but the signature was wrong. Since the mid is not put in the
 * pending queue until later (when it is about to be dispatched)
 * we do have to limit the number of outstanding requests
 * to somewhat less than 64K-1 although it is hard to imagine
 * so many threads being in the vfs at one time.
 */
__u64 GetNextMid(struct TCP_Server_Info *server)
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{
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	__u64 mid = 0;
	__u16 last_mid, cur_mid;
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	bool collision;
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	spin_lock(&GlobalMid_Lock);
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	/* mid is 16 bit only for CIFS/SMB */
	cur_mid = (__u16)((server->CurrentMid) & 0xffff);
	/* we do not want to loop forever */
	last_mid = cur_mid;
	cur_mid++;

	/*
	 * This nested loop looks more expensive than it is.
	 * In practice the list of pending requests is short,
	 * fewer than 50, and the mids are likely to be unique
	 * on the first pass through the loop unless some request
	 * takes longer than the 64 thousand requests before it
	 * (and it would also have to have been a request that
	 * did not time out).
	 */
	while (cur_mid != last_mid) {
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		struct mid_q_entry *mid_entry;
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		unsigned int num_mids;
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		collision = false;
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		if (cur_mid == 0)
			cur_mid++;
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		num_mids = 0;
		list_for_each_entry(mid_entry, &server->pending_mid_q, qhead) {
			++num_mids;
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			if (mid_entry->mid == cur_mid &&
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			    mid_entry->mid_state == MID_REQUEST_SUBMITTED) {
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				/* This mid is in use, try a different one */
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				collision = true;
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				break;
			}
		}
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		/*
		 * if we have more than 32k mids in the list, then something
		 * is very wrong. Possibly a local user is trying to DoS the
		 * box by issuing long-running calls and SIGKILL'ing them. If
		 * we get to 2^16 mids then we're in big trouble as this
		 * function could loop forever.
		 *
		 * Go ahead and assign out the mid in this situation, but force
		 * an eventual reconnect to clean out the pending_mid_q.
		 */
		if (num_mids > 32768)
			server->tcpStatus = CifsNeedReconnect;

		if (!collision) {
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			mid = (__u64)cur_mid;
			server->CurrentMid = mid;
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			break;
		}
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		cur_mid++;
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	}
	spin_unlock(&GlobalMid_Lock);
	return mid;
}

/* NB: MID can not be set if treeCon not passed in, in that
   case it is responsbility of caller to set the mid */
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void
header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
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		const struct cifs_tcon *treeCon, int word_count
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		/* length of fixed section (word count) in two byte units  */)
{
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	struct list_head *temp_item;
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	struct cifs_ses *ses;
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	char *temp = (char *) buffer;

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	memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
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	buffer->smb_buf_length = cpu_to_be32(
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	    (2 * word_count) + sizeof(struct smb_hdr) -
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	    4 /*  RFC 1001 length field does not count */  +
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	    2 /* for bcc field itself */) ;
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	buffer->Protocol[0] = 0xFF;
	buffer->Protocol[1] = 'S';
	buffer->Protocol[2] = 'M';
	buffer->Protocol[3] = 'B';
	buffer->Command = smb_command;
	buffer->Flags = 0x00;	/* case sensitive */
	buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
	buffer->Pid = cpu_to_le16((__u16)current->tgid);
	buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
	if (treeCon) {
		buffer->Tid = treeCon->tid;
		if (treeCon->ses) {
			if (treeCon->ses->capabilities & CAP_UNICODE)
				buffer->Flags2 |= SMBFLG2_UNICODE;
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			if (treeCon->ses->capabilities & CAP_STATUS32)
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				buffer->Flags2 |= SMBFLG2_ERR_STATUS;
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			/* Uid is not converted */
			buffer->Uid = treeCon->ses->Suid;
			buffer->Mid = GetNextMid(treeCon->ses->server);
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			if (multiuser_mount != 0) {
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		/* For the multiuser case, there are few obvious technically  */
		/* possible mechanisms to match the local linux user (uid)    */
		/* to a valid remote smb user (smb_uid):		      */
		/* 	1) Query Winbind (or other local pam/nss daemon       */
		/* 	  for userid/password/logon_domain or credential      */
		/*      2) Query Winbind for uid to sid to username mapping   */
		/* 	   and see if we have a matching password for existing*/
		/*         session for that user perhas getting password by   */
		/*         adding a new pam_cifs module that stores passwords */
		/*         so that the cifs vfs can get at that for all logged*/
		/*	   on users					      */
		/*	3) (Which is the mechanism we have chosen)	      */
		/*	   Search through sessions to the same server for a   */
		/*	   a match on the uid that was passed in on mount     */
		/*         with the current processes uid (or euid?) and use  */
		/* 	   that smb uid.   If no existing smb session for     */
		/* 	   that uid found, use the default smb session ie     */
		/*         the smb session for the volume mounted which is    */
		/* 	   the same as would be used if the multiuser mount   */
		/* 	   flag were disabled.  */

		/*  BB Add support for establishing new tCon and SMB Session  */
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		/*      with userid/password pairs found on the smb session   */
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		/*	for other target tcp/ip addresses 		BB    */
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				if (current_fsuid() != treeCon->ses->linux_uid) {
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					cFYI(1, "Multiuser mode and UID "
						 "did not match tcon uid");
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					spin_lock(&cifs_tcp_ses_lock);
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					list_for_each(temp_item, &treeCon->ses->server->smb_ses_list) {
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						ses = list_entry(temp_item, struct cifs_ses, smb_ses_list);
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						if (ses->linux_uid == current_fsuid()) {
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							if (ses->server == treeCon->ses->server) {
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								cFYI(1, "found matching uid substitute right smb_uid");
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								buffer->Uid = ses->Suid;
								break;
							} else {
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				/* BB eventually call cifs_setup_session here */
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								cFYI(1, "local UID found but no smb sess with this server exists");
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							}
						}
					}
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					spin_unlock(&cifs_tcp_ses_lock);
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				}
			}
		}
		if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
			buffer->Flags2 |= SMBFLG2_DFS;
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		if (treeCon->nocase)
			buffer->Flags  |= SMBFLG_CASELESS;
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		if ((treeCon->ses) && (treeCon->ses->server))
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			if (treeCon->ses->server->sec_mode &
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			  (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
				buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
	}

/*  endian conversion of flags is now done just before sending */
	buffer->WordCount = (char) word_count;
	return;
}

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static int
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check_smb_hdr(struct smb_hdr *smb, __u16 mid)
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{
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	/* does it have the right SMB "signature" ? */
	if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
		cERROR(1, "Bad protocol string signature header 0x%x",
			*(unsigned int *)smb->Protocol);
		return 1;
	}

	/* Make sure that message ids match */
	if (mid != smb->Mid) {
		cERROR(1, "Mids do not match. received=%u expected=%u",
			smb->Mid, mid);
		return 1;
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	}
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	/* if it's a response then accept */
	if (smb->Flags & SMBFLG_RESPONSE)
		return 0;

	/* only one valid case where server sends us request */
	if (smb->Command == SMB_COM_LOCKING_ANDX)
		return 0;

	cERROR(1, "Server sent request, not response. mid=%u", smb->Mid);
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	return 1;
}

int
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checkSMB(char *buf, unsigned int total_read)
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{
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	struct smb_hdr *smb = (struct smb_hdr *)buf;
	__u16 mid = smb->Mid;
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	__u32 rfclen = be32_to_cpu(smb->smb_buf_length);
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	__u32 clc_len;  /* calculated length */
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	cFYI(0, "checkSMB Length: 0x%x, smb_buf_length: 0x%x",
		total_read, rfclen);
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	/* is this frame too small to even get to a BCC? */
	if (total_read < 2 + sizeof(struct smb_hdr)) {
		if ((total_read >= sizeof(struct smb_hdr) - 1)
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			    && (smb->Status.CifsError != 0)) {
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			/* it's an error return */
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			smb->WordCount = 0;
			/* some error cases do not return wct and bcc */
			return 0;
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		} else if ((total_read == sizeof(struct smb_hdr) + 1) &&
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				(smb->WordCount == 0)) {
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			char *tmp = (char *)smb;
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			/* Need to work around a bug in two servers here */
			/* First, check if the part of bcc they sent was zero */
			if (tmp[sizeof(struct smb_hdr)] == 0) {
				/* some servers return only half of bcc
				 * on simple responses (wct, bcc both zero)
				 * in particular have seen this on
				 * ulogoffX and FindClose. This leaves
				 * one byte of bcc potentially unitialized
				 */
				/* zero rest of bcc */
				tmp[sizeof(struct smb_hdr)+1] = 0;
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				return 0;
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			}
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			cERROR(1, "rcvd invalid byte count (bcc)");
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		} else {
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			cERROR(1, "Length less than smb header size");
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		}
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		return -EIO;
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	}

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	/* otherwise, there is enough to get to the BCC */
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	if (check_smb_hdr(smb, mid))
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		return -EIO;
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	clc_len = smbCalcSize(smb);
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	if (4 + rfclen != total_read) {
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		cERROR(1, "Length read does not match RFC1001 length %d",
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				rfclen);
		return -EIO;
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	}

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	if (4 + rfclen != clc_len) {
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		/* check if bcc wrapped around for large read responses */
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		if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {
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			/* check if lengths match mod 64K */
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			if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))
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				return 0; /* bcc wrapped */
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		}
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		cFYI(1, "Calculated size %u vs length %u mismatch for mid=%u",
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				clc_len, 4 + rfclen, smb->Mid);
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		if (4 + rfclen < clc_len) {
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			cERROR(1, "RFC1001 size %u smaller than SMB for mid=%u",
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					rfclen, smb->Mid);
			return -EIO;
		} else if (rfclen > clc_len + 512) {
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			/*
			 * Some servers (Windows XP in particular) send more
			 * data than the lengths in the SMB packet would
			 * indicate on certain calls (byte range locks and
			 * trans2 find first calls in particular). While the
			 * client can handle such a frame by ignoring the
			 * trailing data, we choose limit the amount of extra
			 * data to 512 bytes.
			 */
			cERROR(1, "RFC1001 size %u more than 512 bytes larger "
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				  "than SMB for mid=%u", rfclen, smb->Mid);
			return -EIO;
509
		}
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	}
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	return 0;
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}
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bool
515
is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
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{
517
	struct smb_hdr *buf = (struct smb_hdr *)buffer;
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	struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
519
	struct list_head *tmp, *tmp1, *tmp2;
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	struct cifs_ses *ses;
	struct cifs_tcon *tcon;
522
	struct cifsInodeInfo *pCifsInode;
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	struct cifsFileInfo *netfile;

525
	cFYI(1, "Checking for oplock break or dnotify response");
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	if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
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	   (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
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		struct smb_com_transaction_change_notify_rsp *pSMBr =
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			(struct smb_com_transaction_change_notify_rsp *)buf;
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		struct file_notify_information *pnotify;
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		__u32 data_offset = 0;
532
		if (get_bcc(buf) > sizeof(struct file_notify_information)) {
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			data_offset = le32_to_cpu(pSMBr->DataOffset);

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			pnotify = (struct file_notify_information *)
				((char *)&pSMBr->hdr.Protocol + data_offset);
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			cFYI(1, "dnotify on %s Action: 0x%x",
				 pnotify->FileName, pnotify->Action);
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			/*   cifs_dump_mem("Rcvd notify Data: ",buf,
540
				sizeof(struct smb_hdr)+60); */
541
			return true;
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		}
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		if (pSMBr->hdr.Status.CifsError) {
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			cFYI(1, "notify err 0x%d",
				pSMBr->hdr.Status.CifsError);
546
			return true;
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		}
548
		return false;
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	}
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	if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
551
		return false;
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	if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
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		/* no sense logging error on invalid handle on oplock
		   break - harmless race between close request and oplock
		   break response is expected from time to time writing out
		   large dirty files cached on the client */
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		if ((NT_STATUS_INVALID_HANDLE) ==
		   le32_to_cpu(pSMB->hdr.Status.CifsError)) {
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			cFYI(1, "invalid handle on oplock break");
560
			return true;
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		} else if (ERRbadfid ==
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		   le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
563
			return true;
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		} else {
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			return false; /* on valid oplock brk we get "request" */
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		}
	}
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	if (pSMB->hdr.WordCount != 8)
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		return false;
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	cFYI(1, "oplock type 0x%d level 0x%d",
		 pSMB->LockType, pSMB->OplockLevel);
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	if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
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		return false;
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	/* look up tcon based on tid & uid */
577
	spin_lock(&cifs_tcp_ses_lock);
578
	list_for_each(tmp, &srv->smb_ses_list) {
579
		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
580
		list_for_each(tmp1, &ses->tcon_list) {
581
			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
582 583 584
			if (tcon->tid != buf->Tid)
				continue;

585
			cifs_stats_inc(&tcon->num_oplock_brks);
586
			spin_lock(&cifs_file_list_lock);
587 588
			list_for_each(tmp2, &tcon->openFileList) {
				netfile = list_entry(tmp2, struct cifsFileInfo,
589
						     tlist);
590 591 592
				if (pSMB->Fid != netfile->netfid)
					continue;

593
				cFYI(1, "file id match, oplock break");
594
				pCifsInode = CIFS_I(netfile->dentry->d_inode);
595

596
				cifs_set_oplock_level(pCifsInode,
597
					pSMB->OplockLevel ? OPLOCK_READ : 0);
598 599
				queue_work(system_nrt_wq,
					   &netfile->oplock_break);
600 601
				netfile->oplock_break_cancelled = false;

602
				spin_unlock(&cifs_file_list_lock);
603
				spin_unlock(&cifs_tcp_ses_lock);
604
				return true;
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			}
606
			spin_unlock(&cifs_file_list_lock);
607
			spin_unlock(&cifs_tcp_ses_lock);
608
			cFYI(1, "No matching file for oplock break");
609
			return true;
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		}
	}
612
	spin_unlock(&cifs_tcp_ses_lock);
613
	cFYI(1, "Can not process oplock break for non-existent connection");
614
	return true;
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}

void
618
dump_smb(void *buf, int smb_buf_length)
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{
	int i, j;
	char debug_line[17];
622
	unsigned char *buffer = buf;
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	if (traceSMB == 0)
		return;

	for (i = 0, j = 0; i < smb_buf_length; i++, j++) {
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		if (i % 8 == 0) {
			/* have reached the beginning of line */
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			printk(KERN_DEBUG "| ");
			j = 0;
		}
		printk("%0#4x ", buffer[i]);
		debug_line[2 * j] = ' ';
		if (isprint(buffer[i]))
			debug_line[1 + (2 * j)] = buffer[i];
		else
			debug_line[1 + (2 * j)] = '_';

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		if (i % 8 == 7) {
			/* reached end of line, time to print ascii */
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			debug_line[16] = 0;
			printk(" | %s\n", debug_line);
		}
	}
	for (; j < 8; j++) {
		printk("     ");
		debug_line[2 * j] = ' ';
		debug_line[1 + (2 * j)] = ' ';
	}
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	printk(" | %s\n", debug_line);
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	return;
}
654

655 656 657 658
void
cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
{
	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
659
		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
660
		cERROR(1, "Autodisabling the use of server inode numbers on "
661 662 663 664
			   "%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.",
665
			   cifs_sb_master_tcon(cifs_sb)->treeName);
666 667
	}
}
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669
void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
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{
671
	oplock &= 0xF;
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673
	if (oplock == OPLOCK_EXCLUSIVE) {
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		cinode->clientCanCacheAll = true;
		cinode->clientCanCacheRead = true;
676 677 678
		cFYI(1, "Exclusive Oplock granted on inode %p",
		     &cinode->vfs_inode);
	} else if (oplock == OPLOCK_READ) {
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		cinode->clientCanCacheAll = false;
		cinode->clientCanCacheRead = true;
681 682
		cFYI(1, "Level II Oplock granted on inode %p",
		    &cinode->vfs_inode);
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	} else {
		cinode->clientCanCacheAll = false;
		cinode->clientCanCacheRead = false;
	}
}
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bool
backup_cred(struct cifs_sb_info *cifs_sb)
{
	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {
		if (cifs_sb->mnt_backupuid == current_fsuid())
			return true;
	}
	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {
		if (in_group_p(cifs_sb->mnt_backupgid))
			return true;
	}

	return false;
}
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void
cifs_add_credits(struct TCP_Server_Info *server, const unsigned int add)
{
	spin_lock(&server->req_lock);
	server->credits += add;
	server->in_flight--;
	spin_unlock(&server->req_lock);
	wake_up(&server->request_q);
}

void
cifs_set_credits(struct TCP_Server_Info *server, const int val)
{
	spin_lock(&server->req_lock);
	server->credits = val;
	server->oplocks = val > 1 ? enable_oplocks : false;
	spin_unlock(&server->req_lock);
}