/*
   *  SMB1 (CIFS) version specific operations
   *
   *  Copyright (c) 2012, Jeff Layton <jlayton@redhat.com>
   *
   *  This library is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License v2 as published
   *  by the Free Software Foundation.
   *
   *  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
   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   */

  #include <linux/pagemap.h>

  #include <linux/vfs.h>

  #include "cifsglob.h"

  #include "cifsproto.h"
  #include "cifs_debug.h"

  #include "cifspdu.h"

  
  /*
   * An NT cancel request header looks just like the original request except:
   *
   * The Command is SMB_COM_NT_CANCEL
   * The WordCount is zeroed out
   * The ByteCount is zeroed out
   *
   * This function mangles an existing request buffer into a
   * SMB_COM_NT_CANCEL request and then sends it.
   */
  static int
  send_nt_cancel(struct TCP_Server_Info *server, void *buf,
  	       struct mid_q_entry *mid)
  {
  	int rc = 0;
  	struct smb_hdr *in_buf = (struct smb_hdr *)buf;
  
  	/* -4 for RFC1001 length and +2 for BCC field */
  	in_buf->smb_buf_length = cpu_to_be32(sizeof(struct smb_hdr) - 4  + 2);
  	in_buf->Command = SMB_COM_NT_CANCEL;
  	in_buf->WordCount = 0;
  	put_bcc(0, in_buf);
  
  	mutex_lock(&server->srv_mutex);
  	rc = cifs_sign_smb(in_buf, server, &mid->sequence_number);
  	if (rc) {
  		mutex_unlock(&server->srv_mutex);
  		return rc;
  	}

  
  	/*
  	 * The response to this call was already factored into the sequence
  	 * number when the call went out, so we must adjust it back downward
  	 * after signing here.
  	 */
  	--server->sequence_number;

  	rc = smb_send(server, in_buf, be32_to_cpu(in_buf->smb_buf_length));

  	if (rc < 0)
  		server->sequence_number--;

  	mutex_unlock(&server->srv_mutex);

  	cifs_dbg(FYI, "issued NT_CANCEL for mid %u, rc = %d
  ",

  		 get_mid(in_buf), rc);

  
  	return rc;
  }

  static bool
  cifs_compare_fids(struct cifsFileInfo *ob1, struct cifsFileInfo *ob2)
  {

  	return ob1->fid.netfid == ob2->fid.netfid;

  }

  static unsigned int
  cifs_read_data_offset(char *buf)
  {
  	READ_RSP *rsp = (READ_RSP *)buf;
  	return le16_to_cpu(rsp->DataOffset);
  }
  
  static unsigned int
  cifs_read_data_length(char *buf)
  {
  	READ_RSP *rsp = (READ_RSP *)buf;
  	return (le16_to_cpu(rsp->DataLengthHigh) << 16) +
  	       le16_to_cpu(rsp->DataLength);
  }

  static struct mid_q_entry *
  cifs_find_mid(struct TCP_Server_Info *server, char *buffer)
  {
  	struct smb_hdr *buf = (struct smb_hdr *)buffer;
  	struct mid_q_entry *mid;
  
  	spin_lock(&GlobalMid_Lock);
  	list_for_each_entry(mid, &server->pending_mid_q, qhead) {

  		if (compare_mid(mid->mid, buf) &&

  		    mid->mid_state == MID_REQUEST_SUBMITTED &&
  		    le16_to_cpu(mid->command) == buf->Command) {
  			spin_unlock(&GlobalMid_Lock);
  			return mid;
  		}
  	}
  	spin_unlock(&GlobalMid_Lock);
  	return NULL;
  }

  static void

  cifs_add_credits(struct TCP_Server_Info *server, const unsigned int add,
  		 const int optype)

  {
  	spin_lock(&server->req_lock);
  	server->credits += add;
  	server->in_flight--;
  	spin_unlock(&server->req_lock);
  	wake_up(&server->request_q);
  }
  
  static 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);
  }
  
  static int *

  cifs_get_credits_field(struct TCP_Server_Info *server, const int optype)

  {
  	return &server->credits;
  }

  static unsigned int
  cifs_get_credits(struct mid_q_entry *mid)
  {
  	return 1;
  }

  /*
   * 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.
   */
  static __u64
  cifs_get_next_mid(struct TCP_Server_Info *server)
  {
  	__u64 mid = 0;
  	__u16 last_mid, cur_mid;
  	bool collision;
  
  	spin_lock(&GlobalMid_Lock);
  
  	/* 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) {
  		struct mid_q_entry *mid_entry;
  		unsigned int num_mids;
  
  		collision = false;
  		if (cur_mid == 0)
  			cur_mid++;
  
  		num_mids = 0;
  		list_for_each_entry(mid_entry, &server->pending_mid_q, qhead) {
  			++num_mids;
  			if (mid_entry->mid == cur_mid &&
  			    mid_entry->mid_state == MID_REQUEST_SUBMITTED) {
  				/* This mid is in use, try a different one */
  				collision = true;
  				break;
  			}
  		}
  
  		/*
  		 * 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) {
  			mid = (__u64)cur_mid;
  			server->CurrentMid = mid;
  			break;
  		}
  		cur_mid++;
  	}
  	spin_unlock(&GlobalMid_Lock);
  	return mid;
  }

  /*
  	return codes:
  		0	not a transact2, or all data present
  		>0	transact2 with that much data missing
  		-EINVAL	invalid transact2
   */
  static int
  check2ndT2(char *buf)
  {
  	struct smb_hdr *pSMB = (struct smb_hdr *)buf;
  	struct smb_t2_rsp *pSMBt;
  	int remaining;
  	__u16 total_data_size, data_in_this_rsp;
  
  	if (pSMB->Command != SMB_COM_TRANSACTION2)
  		return 0;
  
  	/* check for plausible wct, bcc and t2 data and parm sizes */
  	/* check for parm and data offset going beyond end of smb */
  	if (pSMB->WordCount != 10) { /* coalesce_t2 depends on this */

  		cifs_dbg(FYI, "invalid transact2 word count
  ");

  		return -EINVAL;
  	}
  
  	pSMBt = (struct smb_t2_rsp *)pSMB;
  
  	total_data_size = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
  	data_in_this_rsp = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
  
  	if (total_data_size == data_in_this_rsp)
  		return 0;
  	else if (total_data_size < data_in_this_rsp) {

  		cifs_dbg(FYI, "total data %d smaller than data in frame %d
  ",
  			 total_data_size, data_in_this_rsp);

  		return -EINVAL;
  	}
  
  	remaining = total_data_size - data_in_this_rsp;

  	cifs_dbg(FYI, "missing %d bytes from transact2, check next response
  ",
  		 remaining);

  	if (total_data_size > CIFSMaxBufSize) {

  		cifs_dbg(VFS, "TotalDataSize %d is over maximum buffer %d
  ",
  			 total_data_size, CIFSMaxBufSize);

  		return -EINVAL;
  	}
  	return remaining;
  }
  
  static int
  coalesce_t2(char *second_buf, struct smb_hdr *target_hdr)
  {
  	struct smb_t2_rsp *pSMBs = (struct smb_t2_rsp *)second_buf;
  	struct smb_t2_rsp *pSMBt  = (struct smb_t2_rsp *)target_hdr;
  	char *data_area_of_tgt;
  	char *data_area_of_src;
  	int remaining;
  	unsigned int byte_count, total_in_tgt;
  	__u16 tgt_total_cnt, src_total_cnt, total_in_src;
  
  	src_total_cnt = get_unaligned_le16(&pSMBs->t2_rsp.TotalDataCount);
  	tgt_total_cnt = get_unaligned_le16(&pSMBt->t2_rsp.TotalDataCount);
  
  	if (tgt_total_cnt != src_total_cnt)

  		cifs_dbg(FYI, "total data count of primary and secondary t2 differ source=%hu target=%hu
  ",
  			 src_total_cnt, tgt_total_cnt);

  
  	total_in_tgt = get_unaligned_le16(&pSMBt->t2_rsp.DataCount);
  
  	remaining = tgt_total_cnt - total_in_tgt;
  
  	if (remaining < 0) {

  		cifs_dbg(FYI, "Server sent too much data. tgt_total_cnt=%hu total_in_tgt=%hu
  ",
  			 tgt_total_cnt, total_in_tgt);

  		return -EPROTO;
  	}
  
  	if (remaining == 0) {
  		/* nothing to do, ignore */

  		cifs_dbg(FYI, "no more data remains
  ");

  		return 0;
  	}
  
  	total_in_src = get_unaligned_le16(&pSMBs->t2_rsp.DataCount);
  	if (remaining < total_in_src)

  		cifs_dbg(FYI, "transact2 2nd response contains too much data
  ");

  
  	/* find end of first SMB data area */
  	data_area_of_tgt = (char *)&pSMBt->hdr.Protocol +
  				get_unaligned_le16(&pSMBt->t2_rsp.DataOffset);
  
  	/* validate target area */
  	data_area_of_src = (char *)&pSMBs->hdr.Protocol +
  				get_unaligned_le16(&pSMBs->t2_rsp.DataOffset);
  
  	data_area_of_tgt += total_in_tgt;
  
  	total_in_tgt += total_in_src;
  	/* is the result too big for the field? */
  	if (total_in_tgt > USHRT_MAX) {

  		cifs_dbg(FYI, "coalesced DataCount too large (%u)
  ",
  			 total_in_tgt);

  		return -EPROTO;
  	}
  	put_unaligned_le16(total_in_tgt, &pSMBt->t2_rsp.DataCount);
  
  	/* fix up the BCC */
  	byte_count = get_bcc(target_hdr);
  	byte_count += total_in_src;
  	/* is the result too big for the field? */
  	if (byte_count > USHRT_MAX) {

  		cifs_dbg(FYI, "coalesced BCC too large (%u)
  ", byte_count);

  		return -EPROTO;
  	}
  	put_bcc(byte_count, target_hdr);
  
  	byte_count = be32_to_cpu(target_hdr->smb_buf_length);
  	byte_count += total_in_src;
  	/* don't allow buffer to overflow */
  	if (byte_count > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {

  		cifs_dbg(FYI, "coalesced BCC exceeds buffer size (%u)
  ",
  			 byte_count);

  		return -ENOBUFS;
  	}
  	target_hdr->smb_buf_length = cpu_to_be32(byte_count);
  
  	/* copy second buffer into end of first buffer */
  	memcpy(data_area_of_tgt, data_area_of_src, total_in_src);
  
  	if (remaining != total_in_src) {
  		/* more responses to go */

  		cifs_dbg(FYI, "waiting for more secondary responses
  ");

  		return 1;
  	}
  
  	/* we are done */

  	cifs_dbg(FYI, "found the last secondary response
  ");

  	return 0;
  }

  static void
  cifs_downgrade_oplock(struct TCP_Server_Info *server,
  			struct cifsInodeInfo *cinode, bool set_level2)
  {
  	if (set_level2)
  		cifs_set_oplock_level(cinode, OPLOCK_READ);
  	else
  		cifs_set_oplock_level(cinode, 0);
  }

  static bool
  cifs_check_trans2(struct mid_q_entry *mid, struct TCP_Server_Info *server,
  		  char *buf, int malformed)
  {
  	if (malformed)
  		return false;
  	if (check2ndT2(buf) <= 0)
  		return false;
  	mid->multiRsp = true;
  	if (mid->resp_buf) {
  		/* merge response - fix up 1st*/
  		malformed = coalesce_t2(buf, mid->resp_buf);
  		if (malformed > 0)
  			return true;
  		/* All parts received or packet is malformed. */
  		mid->multiEnd = true;
  		dequeue_mid(mid, malformed);
  		return true;
  	}
  	if (!server->large_buf) {
  		/*FIXME: switch to already allocated largebuf?*/

  		cifs_dbg(VFS, "1st trans2 resp needs bigbuf
  ");

  	} else {
  		/* Have first buffer */
  		mid->resp_buf = buf;
  		mid->large_buf = true;
  		server->bigbuf = NULL;
  	}
  	return true;
  }

  static bool
  cifs_need_neg(struct TCP_Server_Info *server)
  {
  	return server->maxBuf == 0;
  }
  
  static int
  cifs_negotiate(const unsigned int xid, struct cifs_ses *ses)
  {
  	int rc;
  	rc = CIFSSMBNegotiate(xid, ses);
  	if (rc == -EAGAIN) {
  		/* retry only once on 1st time connection */
  		set_credits(ses->server, 1);
  		rc = CIFSSMBNegotiate(xid, ses);
  		if (rc == -EAGAIN)
  			rc = -EHOSTDOWN;
  	}
  	return rc;
  }

  static unsigned int
  cifs_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
  {
  	__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
  	struct TCP_Server_Info *server = tcon->ses->server;
  	unsigned int wsize;
  
  	/* start with specified wsize, or default */
  	if (volume_info->wsize)
  		wsize = volume_info->wsize;
  	else if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
  		wsize = CIFS_DEFAULT_IOSIZE;
  	else
  		wsize = CIFS_DEFAULT_NON_POSIX_WSIZE;
  
  	/* can server support 24-bit write sizes? (via UNIX extensions) */
  	if (!tcon->unix_ext || !(unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
  		wsize = min_t(unsigned int, wsize, CIFS_MAX_RFC1002_WSIZE);
  
  	/*
  	 * no CAP_LARGE_WRITE_X or is signing enabled without CAP_UNIX set?
  	 * Limit it to max buffer offered by the server, minus the size of the
  	 * WRITEX header, not including the 4 byte RFC1001 length.
  	 */
  	if (!(server->capabilities & CAP_LARGE_WRITE_X) ||

  	    (!(server->capabilities & CAP_UNIX) && server->sign))

  		wsize = min_t(unsigned int, wsize,
  				server->maxBuf - sizeof(WRITE_REQ) + 4);

  	/* hard limit of CIFS_MAX_WSIZE */
  	wsize = min_t(unsigned int, wsize, CIFS_MAX_WSIZE);
  
  	return wsize;
  }
  
  static unsigned int
  cifs_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
  {
  	__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
  	struct TCP_Server_Info *server = tcon->ses->server;
  	unsigned int rsize, defsize;
  
  	/*
  	 * Set default value...
  	 *
  	 * HACK alert! Ancient servers have very small buffers. Even though
  	 * MS-CIFS indicates that servers are only limited by the client's
  	 * bufsize for reads, testing against win98se shows that it throws
  	 * INVALID_PARAMETER errors if you try to request too large a read.
  	 * OS/2 just sends back short reads.
  	 *
  	 * If the server doesn't advertise CAP_LARGE_READ_X, then assume that
  	 * it can't handle a read request larger than its MaxBufferSize either.
  	 */
  	if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_READ_CAP))
  		defsize = CIFS_DEFAULT_IOSIZE;
  	else if (server->capabilities & CAP_LARGE_READ_X)
  		defsize = CIFS_DEFAULT_NON_POSIX_RSIZE;
  	else
  		defsize = server->maxBuf - sizeof(READ_RSP);
  
  	rsize = volume_info->rsize ? volume_info->rsize : defsize;
  
  	/*
  	 * no CAP_LARGE_READ_X? Then MS-CIFS states that we must limit this to
  	 * the client's MaxBufferSize.
  	 */
  	if (!(server->capabilities & CAP_LARGE_READ_X))
  		rsize = min_t(unsigned int, CIFSMaxBufSize, rsize);

  	/* hard limit of CIFS_MAX_RSIZE */
  	rsize = min_t(unsigned int, rsize, CIFS_MAX_RSIZE);
  
  	return rsize;
  }

  static void
  cifs_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon)
  {
  	CIFSSMBQFSDeviceInfo(xid, tcon);
  	CIFSSMBQFSAttributeInfo(xid, tcon);
  }

  static int
  cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
  			struct cifs_sb_info *cifs_sb, const char *full_path)
  {
  	int rc;
  	FILE_ALL_INFO *file_info;
  
  	file_info = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
  	if (file_info == NULL)
  		return -ENOMEM;
  
  	rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
  			      0 /* not legacy */, cifs_sb->local_nls,
  			      cifs_sb->mnt_cifs_flags &
  				CIFS_MOUNT_MAP_SPECIAL_CHR);
  
  	if (rc == -EOPNOTSUPP || rc == -EINVAL)
  		rc = SMBQueryInformation(xid, tcon, full_path, file_info,
  				cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
  				  CIFS_MOUNT_MAP_SPECIAL_CHR);
  	kfree(file_info);
  	return rc;
  }

  static int
  cifs_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
  		     struct cifs_sb_info *cifs_sb, const char *full_path,

  		     FILE_ALL_INFO *data, bool *adjustTZ, bool *symlink)

  {
  	int rc;

  	*symlink = false;

  	/* could do find first instead but this returns more info */
  	rc = CIFSSMBQPathInfo(xid, tcon, full_path, data, 0 /* not legacy */,
  			      cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
  						CIFS_MOUNT_MAP_SPECIAL_CHR);
  	/*
  	 * BB optimize code so we do not make the above call when server claims
  	 * no NT SMB support and the above call failed at least once - set flag
  	 * in tcon or mount.
  	 */
  	if ((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
  		rc = SMBQueryInformation(xid, tcon, full_path, data,
  					 cifs_sb->local_nls,
  					 cifs_sb->mnt_cifs_flags &
  						CIFS_MOUNT_MAP_SPECIAL_CHR);
  		*adjustTZ = true;
  	}

  
  	if (!rc && (le32_to_cpu(data->Attributes) & ATTR_REPARSE)) {
  		int tmprc;
  		int oplock = 0;

  		struct cifs_fid fid;
  		struct cifs_open_parms oparms;
  
  		oparms.tcon = tcon;
  		oparms.cifs_sb = cifs_sb;
  		oparms.desired_access = FILE_READ_ATTRIBUTES;
  		oparms.create_options = 0;
  		oparms.disposition = FILE_OPEN;
  		oparms.path = full_path;
  		oparms.fid = &fid;
  		oparms.reconnect = false;

  
  		/* Need to check if this is a symbolic link or not */

  		tmprc = CIFS_open(xid, &oparms, &oplock, NULL);

  		if (tmprc == -EOPNOTSUPP)
  			*symlink = true;
  		else

  			CIFSSMBClose(xid, tcon, fid.netfid);

  	}

  	return rc;
  }
  
  static int
  cifs_get_srv_inum(const unsigned int xid, struct cifs_tcon *tcon,
  		  struct cifs_sb_info *cifs_sb, const char *full_path,
  		  u64 *uniqueid, FILE_ALL_INFO *data)
  {
  	/*
  	 * We can not use the IndexNumber field by default from Windows or
  	 * Samba (in ALL_INFO buf) but we can request it explicitly. The SNIA
  	 * CIFS spec claims that this value is unique within the scope of a
  	 * share, and the windows docs hint that it's actually unique
  	 * per-machine.
  	 *
  	 * There may be higher info levels that work but are there Windows
  	 * server or network appliances for which IndexNumber field is not
  	 * guaranteed unique?
  	 */
  	return CIFSGetSrvInodeNumber(xid, tcon, full_path, uniqueid,
  				     cifs_sb->local_nls,
  				     cifs_sb->mnt_cifs_flags &
  						CIFS_MOUNT_MAP_SPECIAL_CHR);
  }

  static int
  cifs_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
  		     struct cifs_fid *fid, FILE_ALL_INFO *data)
  {
  	return CIFSSMBQFileInfo(xid, tcon, fid->netfid, data);
  }

  static void
  cifs_clear_stats(struct cifs_tcon *tcon)
  {
  #ifdef CONFIG_CIFS_STATS
  	atomic_set(&tcon->stats.cifs_stats.num_writes, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_reads, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_flushes, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_oplock_brks, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_opens, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_posixopens, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_posixmkdirs, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_closes, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_deletes, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_mkdirs, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_rmdirs, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_renames, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_t2renames, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_ffirst, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_fnext, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_fclose, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_hardlinks, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_symlinks, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_locks, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_acl_get, 0);
  	atomic_set(&tcon->stats.cifs_stats.num_acl_set, 0);
  #endif
  }
  
  static void
  cifs_print_stats(struct seq_file *m, struct cifs_tcon *tcon)
  {
  #ifdef CONFIG_CIFS_STATS
  	seq_printf(m, " Oplocks breaks: %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_oplock_brks));
  	seq_printf(m, "
  Reads:  %d Bytes: %llu",
  		   atomic_read(&tcon->stats.cifs_stats.num_reads),
  		   (long long)(tcon->bytes_read));
  	seq_printf(m, "
  Writes: %d Bytes: %llu",
  		   atomic_read(&tcon->stats.cifs_stats.num_writes),
  		   (long long)(tcon->bytes_written));
  	seq_printf(m, "
  Flushes: %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_flushes));
  	seq_printf(m, "
  Locks: %d HardLinks: %d Symlinks: %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_locks),
  		   atomic_read(&tcon->stats.cifs_stats.num_hardlinks),
  		   atomic_read(&tcon->stats.cifs_stats.num_symlinks));
  	seq_printf(m, "
  Opens: %d Closes: %d Deletes: %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_opens),
  		   atomic_read(&tcon->stats.cifs_stats.num_closes),
  		   atomic_read(&tcon->stats.cifs_stats.num_deletes));
  	seq_printf(m, "
  Posix Opens: %d Posix Mkdirs: %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_posixopens),
  		   atomic_read(&tcon->stats.cifs_stats.num_posixmkdirs));
  	seq_printf(m, "
  Mkdirs: %d Rmdirs: %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_mkdirs),
  		   atomic_read(&tcon->stats.cifs_stats.num_rmdirs));
  	seq_printf(m, "
  Renames: %d T2 Renames %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_renames),
  		   atomic_read(&tcon->stats.cifs_stats.num_t2renames));
  	seq_printf(m, "
  FindFirst: %d FNext %d FClose %d",
  		   atomic_read(&tcon->stats.cifs_stats.num_ffirst),
  		   atomic_read(&tcon->stats.cifs_stats.num_fnext),
  		   atomic_read(&tcon->stats.cifs_stats.num_fclose));
  #endif
  }

  static void
  cifs_mkdir_setinfo(struct inode *inode, const char *full_path,
  		   struct cifs_sb_info *cifs_sb, struct cifs_tcon *tcon,
  		   const unsigned int xid)
  {
  	FILE_BASIC_INFO info;
  	struct cifsInodeInfo *cifsInode;
  	u32 dosattrs;
  	int rc;
  
  	memset(&info, 0, sizeof(info));
  	cifsInode = CIFS_I(inode);
  	dosattrs = cifsInode->cifsAttrs|ATTR_READONLY;
  	info.Attributes = cpu_to_le32(dosattrs);
  	rc = CIFSSMBSetPathInfo(xid, tcon, full_path, &info, cifs_sb->local_nls,
  				cifs_sb->mnt_cifs_flags &
  						CIFS_MOUNT_MAP_SPECIAL_CHR);
  	if (rc == 0)
  		cifsInode->cifsAttrs = dosattrs;
  }

  static int

  cifs_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
  	       __u32 *oplock, FILE_ALL_INFO *buf)

  {

  	if (!(oparms->tcon->ses->capabilities & CAP_NT_SMBS))
  		return SMBLegacyOpen(xid, oparms->tcon, oparms->path,
  				     oparms->disposition,
  				     oparms->desired_access,
  				     oparms->create_options,
  				     &oparms->fid->netfid, oplock, buf,
  				     oparms->cifs_sb->local_nls,
  				     oparms->cifs_sb->mnt_cifs_flags

  						& CIFS_MOUNT_MAP_SPECIAL_CHR);

  	return CIFS_open(xid, oparms, oplock, buf);

  }
  
  static void
  cifs_set_fid(struct cifsFileInfo *cfile, struct cifs_fid *fid, __u32 oplock)
  {
  	struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
  	cfile->fid.netfid = fid->netfid;
  	cifs_set_oplock_level(cinode, oplock);

  	cinode->can_cache_brlcks = CIFS_CACHE_WRITE(cinode);

  }

  static void

  cifs_close_file(const unsigned int xid, struct cifs_tcon *tcon,
  		struct cifs_fid *fid)
  {

  	CIFSSMBClose(xid, tcon, fid->netfid);

  }

  static int
  cifs_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
  		struct cifs_fid *fid)
  {
  	return CIFSSMBFlush(xid, tcon, fid->netfid);
  }

  static int
  cifs_sync_read(const unsigned int xid, struct cifsFileInfo *cfile,
  	       struct cifs_io_parms *parms, unsigned int *bytes_read,
  	       char **buf, int *buf_type)
  {
  	parms->netfid = cfile->fid.netfid;
  	return CIFSSMBRead(xid, parms, bytes_read, buf, buf_type);
  }

  static int
  cifs_sync_write(const unsigned int xid, struct cifsFileInfo *cfile,
  		struct cifs_io_parms *parms, unsigned int *written,
  		struct kvec *iov, unsigned long nr_segs)
  {
  
  	parms->netfid = cfile->fid.netfid;
  	return CIFSSMBWrite2(xid, parms, written, iov, nr_segs);
  }

  static int
  smb_set_file_info(struct inode *inode, const char *full_path,
  		  FILE_BASIC_INFO *buf, const unsigned int xid)
  {
  	int oplock = 0;
  	int rc;

  	__u32 netpid;

  	struct cifs_fid fid;
  	struct cifs_open_parms oparms;

  	struct cifsFileInfo *open_file;
  	struct cifsInodeInfo *cinode = CIFS_I(inode);
  	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
  	struct tcon_link *tlink = NULL;
  	struct cifs_tcon *tcon;

  
  	/* if the file is already open for write, just use that fileid */
  	open_file = find_writable_file(cinode, true);
  	if (open_file) {

  		fid.netfid = open_file->fid.netfid;

  		netpid = open_file->pid;
  		tcon = tlink_tcon(open_file->tlink);
  		goto set_via_filehandle;
  	}
  
  	tlink = cifs_sb_tlink(cifs_sb);
  	if (IS_ERR(tlink)) {
  		rc = PTR_ERR(tlink);
  		tlink = NULL;
  		goto out;
  	}
  	tcon = tlink_tcon(tlink);

  	rc = CIFSSMBSetPathInfo(xid, tcon, full_path, buf, cifs_sb->local_nls,

  					cifs_sb->mnt_cifs_flags &
  						CIFS_MOUNT_MAP_SPECIAL_CHR);

  	if (rc == 0) {
  		cinode->cifsAttrs = le32_to_cpu(buf->Attributes);
  		goto out;
  	} else if (rc != -EOPNOTSUPP && rc != -EINVAL) {
  		goto out;

  	}

  	oparms.tcon = tcon;
  	oparms.cifs_sb = cifs_sb;
  	oparms.desired_access = SYNCHRONIZE | FILE_WRITE_ATTRIBUTES;
  	oparms.create_options = CREATE_NOT_DIR;
  	oparms.disposition = FILE_OPEN;
  	oparms.path = full_path;
  	oparms.fid = &fid;
  	oparms.reconnect = false;

  	cifs_dbg(FYI, "calling SetFileInfo since SetPathInfo for times not supported by this server
  ");
  	rc = CIFS_open(xid, &oparms, &oplock, NULL);

  	if (rc != 0) {
  		if (rc == -EIO)
  			rc = -EINVAL;
  		goto out;
  	}
  
  	netpid = current->tgid;
  
  set_via_filehandle:

  	rc = CIFSSMBSetFileInfo(xid, tcon, buf, fid.netfid, netpid);

  	if (!rc)
  		cinode->cifsAttrs = le32_to_cpu(buf->Attributes);
  
  	if (open_file == NULL)

  		CIFSSMBClose(xid, tcon, fid.netfid);

  	else
  		cifsFileInfo_put(open_file);
  out:
  	if (tlink != NULL)
  		cifs_put_tlink(tlink);
  	return rc;
  }

  static int

  cifs_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
  		   struct cifsFileInfo *cfile)
  {
  	return CIFSSMB_set_compression(xid, tcon, cfile->fid.netfid);
  }
  
  static int

  cifs_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
  		     const char *path, struct cifs_sb_info *cifs_sb,
  		     struct cifs_fid *fid, __u16 search_flags,
  		     struct cifs_search_info *srch_inf)
  {

  	return CIFSFindFirst(xid, tcon, path, cifs_sb,
  			     &fid->netfid, search_flags, srch_inf, true);

  }
  
  static int
  cifs_query_dir_next(const unsigned int xid, struct cifs_tcon *tcon,
  		    struct cifs_fid *fid, __u16 search_flags,
  		    struct cifs_search_info *srch_inf)
  {
  	return CIFSFindNext(xid, tcon, fid->netfid, search_flags, srch_inf);
  }
  
  static int
  cifs_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
  	       struct cifs_fid *fid)
  {
  	return CIFSFindClose(xid, tcon, fid->netfid);
  }

  static int
  cifs_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
  		     struct cifsInodeInfo *cinode)
  {
  	return CIFSSMBLock(0, tcon, fid->netfid, current->tgid, 0, 0, 0, 0,
  			   LOCKING_ANDX_OPLOCK_RELEASE, false,

  			   CIFS_CACHE_READ(cinode) ? 1 : 0);

  }

  static int
  cifs_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
  	     struct kstatfs *buf)
  {
  	int rc = -EOPNOTSUPP;
  
  	buf->f_type = CIFS_MAGIC_NUMBER;
  
  	/*
  	 * We could add a second check for a QFS Unix capability bit
  	 */
  	if ((tcon->ses->capabilities & CAP_UNIX) &&
  	    (CIFS_POSIX_EXTENSIONS & le64_to_cpu(tcon->fsUnixInfo.Capability)))
  		rc = CIFSSMBQFSPosixInfo(xid, tcon, buf);
  
  	/*
  	 * Only need to call the old QFSInfo if failed on newer one,
  	 * e.g. by OS/2.
  	 **/
  	if (rc && (tcon->ses->capabilities & CAP_NT_SMBS))
  		rc = CIFSSMBQFSInfo(xid, tcon, buf);
  
  	/*
  	 * Some old Windows servers also do not support level 103, retry with
  	 * older level one if old server failed the previous call or we
  	 * bypassed it because we detected that this was an older LANMAN sess
  	 */
  	if (rc)
  		rc = SMBOldQFSInfo(xid, tcon, buf);
  	return rc;
  }

  static int
  cifs_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
  	       __u64 length, __u32 type, int lock, int unlock, bool wait)
  {
  	return CIFSSMBLock(xid, tlink_tcon(cfile->tlink), cfile->fid.netfid,
  			   current->tgid, length, offset, unlock, lock,
  			   (__u8)type, wait, 0);
  }

  static int

  cifs_unix_dfs_readlink(const unsigned int xid, struct cifs_tcon *tcon,
  		       const unsigned char *searchName, char **symlinkinfo,
  		       const struct nls_table *nls_codepage)
  {
  #ifdef CONFIG_CIFS_DFS_UPCALL
  	int rc;
  	unsigned int num_referrals = 0;
  	struct dfs_info3_param *referrals = NULL;
  
  	rc = get_dfs_path(xid, tcon->ses, searchName, nls_codepage,
  			  &num_referrals, &referrals, 0);
  
  	if (!rc && num_referrals > 0) {
  		*symlinkinfo = kstrndup(referrals->node_name,
  					strlen(referrals->node_name),
  					GFP_KERNEL);
  		if (!*symlinkinfo)
  			rc = -ENOMEM;
  		free_dfs_info_array(referrals, num_referrals);
  	}
  	return rc;
  #else /* No DFS support */
  	return -EREMOTE;
  #endif
  }
  
  static int

  cifs_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
  		   const char *full_path, char **target_path,
  		   struct cifs_sb_info *cifs_sb)
  {
  	int rc;
  	int oplock = 0;

  	struct cifs_fid fid;
  	struct cifs_open_parms oparms;

  
  	cifs_dbg(FYI, "%s: path: %s
  ", __func__, full_path);

  	/* Check for unix extensions */
  	if (cap_unix(tcon->ses)) {
  		rc = CIFSSMBUnixQuerySymLink(xid, tcon, full_path, target_path,
  					     cifs_sb->local_nls);

  		if (rc == -EREMOTE)
  			rc = cifs_unix_dfs_readlink(xid, tcon, full_path,
  						    target_path,
  						    cifs_sb->local_nls);

  		goto out;
  	}

  	oparms.tcon = tcon;
  	oparms.cifs_sb = cifs_sb;
  	oparms.desired_access = FILE_READ_ATTRIBUTES;
  	oparms.create_options = OPEN_REPARSE_POINT;
  	oparms.disposition = FILE_OPEN;
  	oparms.path = full_path;
  	oparms.fid = &fid;
  	oparms.reconnect = false;
  
  	rc = CIFS_open(xid, &oparms, &oplock, NULL);

  	if (rc)

  		goto out;

  	rc = CIFSSMBQuerySymLink(xid, tcon, fid.netfid, target_path,

  				 cifs_sb->local_nls);

  	if (rc)
  		goto out_close;

  
  	convert_delimiter(*target_path, '/');

  out_close:

  	CIFSSMBClose(xid, tcon, fid.netfid);

  out:
  	if (!rc)
  		cifs_dbg(FYI, "%s: target path: %s
  ", __func__, *target_path);

  	return rc;
  }

  static bool
  cifs_is_read_op(__u32 oplock)
  {
  	return oplock == OPLOCK_READ;
  }

  static unsigned int
  cifs_wp_retry_size(struct inode *inode)
  {
  	return CIFS_SB(inode->i_sb)->wsize;
  }

  static bool
  cifs_dir_needs_close(struct cifsFileInfo *cfile)
  {
  	return !cfile->srch_inf.endOfSearch && !cfile->invalidHandle;
  }

  struct smb_version_operations smb1_operations = {

  	.send_cancel = send_nt_cancel,

  	.compare_fids = cifs_compare_fids,

  	.setup_request = cifs_setup_request,

  	.setup_async_request = cifs_setup_async_request,

  	.check_receive = cifs_check_receive,

  	.add_credits = cifs_add_credits,
  	.set_credits = cifs_set_credits,
  	.get_credits_field = cifs_get_credits_field,

  	.get_credits = cifs_get_credits,

  	.wait_mtu_credits = cifs_wait_mtu_credits,

  	.get_next_mid = cifs_get_next_mid,

  	.read_data_offset = cifs_read_data_offset,
  	.read_data_length = cifs_read_data_length,
  	.map_error = map_smb_to_linux_error,

  	.find_mid = cifs_find_mid,
  	.check_message = checkSMB,
  	.dump_detail = cifs_dump_detail,

  	.clear_stats = cifs_clear_stats,
  	.print_stats = cifs_print_stats,

  	.is_oplock_break = is_valid_oplock_break,

  	.downgrade_oplock = cifs_downgrade_oplock,

  	.check_trans2 = cifs_check_trans2,

  	.need_neg = cifs_need_neg,
  	.negotiate = cifs_negotiate,

  	.negotiate_wsize = cifs_negotiate_wsize,
  	.negotiate_rsize = cifs_negotiate_rsize,

  	.sess_setup = CIFS_SessSetup,
  	.logoff = CIFSSMBLogoff,

  	.tree_connect = CIFSTCon,
  	.tree_disconnect = CIFSSMBTDis,

  	.get_dfs_refer = CIFSGetDFSRefer,

  	.qfs_tcon = cifs_qfs_tcon,

  	.is_path_accessible = cifs_is_path_accessible,

  	.query_path_info = cifs_query_path_info,

  	.query_file_info = cifs_query_file_info,

  	.get_srv_inum = cifs_get_srv_inum,

  	.set_path_size = CIFSSMBSetEOF,
  	.set_file_size = CIFSSMBSetFileSize,

  	.set_file_info = smb_set_file_info,

  	.set_compression = cifs_set_compression,

  	.echo = CIFSSMBEcho,

  	.mkdir = CIFSSMBMkDir,
  	.mkdir_setinfo = cifs_mkdir_setinfo,

  	.rmdir = CIFSSMBRmDir,

  	.unlink = CIFSSMBDelFile,
  	.rename_pending_delete = cifs_rename_pending_delete,

  	.rename = CIFSSMBRename,

  	.create_hardlink = CIFSCreateHardLink,

  	.query_symlink = cifs_query_symlink,

  	.open = cifs_open_file,
  	.set_fid = cifs_set_fid,

  	.close = cifs_close_file,

  	.flush = cifs_flush_file,

  	.async_readv = cifs_async_readv,

  	.async_writev = cifs_async_writev,

  	.sync_read = cifs_sync_read,

  	.sync_write = cifs_sync_write,

  	.query_dir_first = cifs_query_dir_first,
  	.query_dir_next = cifs_query_dir_next,
  	.close_dir = cifs_close_dir,
  	.calc_smb_size = smbCalcSize,

  	.oplock_response = cifs_oplock_response,

  	.queryfs = cifs_queryfs,

  	.mand_lock = cifs_mand_lock,
  	.mand_unlock_range = cifs_unlock_range,
  	.push_mand_locks = cifs_push_mandatory_locks,

  	.query_mf_symlink = cifs_query_mf_symlink,

  	.create_mf_symlink = cifs_create_mf_symlink,

  	.is_read_op = cifs_is_read_op,

  	.wp_retry_size = cifs_wp_retry_size,

  	.dir_needs_close = cifs_dir_needs_close,

  #ifdef CONFIG_CIFS_XATTR
  	.query_all_EAs = CIFSSMBQAllEAs,
  	.set_EA = CIFSSMBSetEA,
  #endif /* CIFS_XATTR */

  #ifdef CONFIG_CIFS_ACL
  	.get_acl = get_cifs_acl,

  	.get_acl_by_fid = get_cifs_acl_by_fid,

  	.set_acl = set_cifs_acl,
  #endif /* CIFS_ACL */

  };
  
  struct smb_version_values smb1_values = {
  	.version_string = SMB1_VERSION_STRING,

  	.large_lock_type = LOCKING_ANDX_LARGE_FILES,
  	.exclusive_lock_type = 0,
  	.shared_lock_type = LOCKING_ANDX_SHARED_LOCK,
  	.unlock_lock_type = 0,

  	.header_size = sizeof(struct smb_hdr),
  	.max_header_size = MAX_CIFS_HDR_SIZE,

  	.read_rsp_size = sizeof(READ_RSP),

  	.lock_cmd = cpu_to_le16(SMB_COM_LOCKING_ANDX),

  	.cap_unix = CAP_UNIX,
  	.cap_nt_find = CAP_NT_SMBS | CAP_NT_FIND,
  	.cap_large_files = CAP_LARGE_FILES,

  	.signing_enabled = SECMODE_SIGN_ENABLED,
  	.signing_required = SECMODE_SIGN_REQUIRED,

  };