[mirror_ubuntu-bionic-kernel.git] / fs / cifs / transport.c

/*
 *   fs/cifs/transport.c
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2005
 *   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
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 
 */

#include <linux/fs.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/net.h>
#include <linux/delay.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
#include <linux/mempool.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
  
extern mempool_t *cifs_mid_poolp;
extern kmem_cache_t *cifs_oplock_cachep;

static struct mid_q_entry *
AllocMidQEntry(struct smb_hdr *smb_buffer, struct cifsSesInfo *ses)
{
	struct mid_q_entry *temp;

	if (ses == NULL) {
		cERROR(1, ("Null session passed in to AllocMidQEntry"));
		return NULL;
	}
	if (ses->server == NULL) {
		cERROR(1, ("Null TCP session in AllocMidQEntry"));
		return NULL;
	}
	
	temp = (struct mid_q_entry *) mempool_alloc(cifs_mid_poolp,SLAB_KERNEL | SLAB_NOFS);
	if (temp == NULL)
		return temp;
	else {
		memset(temp, 0, sizeof (struct mid_q_entry));
		temp->mid = smb_buffer->Mid;	/* always LE */
		temp->pid = current->pid;
		temp->command = smb_buffer->Command;
		cFYI(1, ("For smb_command %d", temp->command));
		do_gettimeofday(&temp->when_sent);
		temp->ses = ses;
		temp->tsk = current;
	}

	spin_lock(&GlobalMid_Lock);
	list_add_tail(&temp->qhead, &ses->server->pending_mid_q);
	atomic_inc(&midCount);
	temp->midState = MID_REQUEST_ALLOCATED;
	spin_unlock(&GlobalMid_Lock);
	return temp;
}

static void
DeleteMidQEntry(struct mid_q_entry *midEntry)
{
	spin_lock(&GlobalMid_Lock);
	midEntry->midState = MID_FREE;
	list_del(&midEntry->qhead);
	atomic_dec(&midCount);
	spin_unlock(&GlobalMid_Lock);
	if(midEntry->largeBuf)
		cifs_buf_release(midEntry->resp_buf);
	else
		cifs_small_buf_release(midEntry->resp_buf);
	mempool_free(midEntry, cifs_mid_poolp);
}

struct oplock_q_entry *
AllocOplockQEntry(struct inode * pinode, __u16 fid, struct cifsTconInfo * tcon)
{
	struct oplock_q_entry *temp;
	if ((pinode== NULL) || (tcon == NULL)) {
		cERROR(1, ("Null parms passed to AllocOplockQEntry"));
		return NULL;
	}
	temp = (struct oplock_q_entry *) kmem_cache_alloc(cifs_oplock_cachep,
						       SLAB_KERNEL);
	if (temp == NULL)
		return temp;
	else {
		temp->pinode = pinode;
		temp->tcon = tcon;
		temp->netfid = fid;
		spin_lock(&GlobalMid_Lock);
		list_add_tail(&temp->qhead, &GlobalOplock_Q);
		spin_unlock(&GlobalMid_Lock);
	}
	return temp;

}

void DeleteOplockQEntry(struct oplock_q_entry * oplockEntry)
{
	spin_lock(&GlobalMid_Lock); 
    /* should we check if list empty first? */
	list_del(&oplockEntry->qhead);
	spin_unlock(&GlobalMid_Lock);
	kmem_cache_free(cifs_oplock_cachep, oplockEntry);
}

int
smb_send(struct socket *ssocket, struct smb_hdr *smb_buffer,
	 unsigned int smb_buf_length, struct sockaddr *sin)
{
	int rc = 0;
	int i = 0;
	struct msghdr smb_msg;
	struct kvec iov;
	unsigned len = smb_buf_length + 4;

	if(ssocket == NULL)
		return -ENOTSOCK; /* BB eventually add reconnect code here */
	iov.iov_base = smb_buffer;
	iov.iov_len = len;

	smb_msg.msg_name = sin;
	smb_msg.msg_namelen = sizeof (struct sockaddr);
	smb_msg.msg_control = NULL;
	smb_msg.msg_controllen = 0;
	smb_msg.msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; /* BB add more flags?*/

	/* smb header is converted in header_assemble. bcc and rest of SMB word
	   area, and byte area if necessary, is converted to littleendian in 
	   cifssmb.c and RFC1001 len is converted to bigendian in smb_send 
	   Flags2 is converted in SendReceive */

	smb_buffer->smb_buf_length = cpu_to_be32(smb_buffer->smb_buf_length);
	cFYI(1, ("Sending smb of length %d ", smb_buf_length));
	dump_smb(smb_buffer, len);

	while (len > 0) {
		rc = kernel_sendmsg(ssocket, &smb_msg, &iov, 1, len);
		if ((rc == -ENOSPC) || (rc == -EAGAIN)) {
			i++;
			if(i > 60) {
				cERROR(1,
				   ("sends on sock %p stuck for 30 seconds",
				    ssocket));
				rc = -EAGAIN;
				break;
			}
			msleep(500);
			continue;
		}
		if (rc < 0) 
			break;
		iov.iov_base += rc;
		iov.iov_len -= rc;
		len -= rc;
	}

	if (rc < 0) {
		cERROR(1,("Error %d sending data on socket to server.", rc));
	} else {
		rc = 0;
	}

	return rc;
}

#ifdef CIFS_EXPERIMENTAL
/* BB finish off this function, adding support for writing set of pages as iovec */
/* and also adding support for operations that need to parse the response smb    */

int
smb_sendv(struct socket *ssocket, struct smb_hdr *smb_buffer,
	 unsigned int smb_buf_length, struct kvec * write_vector 
	  /* page list */, struct sockaddr *sin)
{
	int rc = 0;
	int i = 0;
	struct msghdr smb_msg;
	number_of_pages += 1; /* account for SMB header */
	struct kvec * piov  = kmalloc(number_of_pages * sizeof(struct kvec));
	unsigned len = smb_buf_length + 4;

	if(ssocket == NULL)
		return -ENOTSOCK; /* BB eventually add reconnect code here */
	iov.iov_base = smb_buffer;
	iov.iov_len = len;

	smb_msg.msg_name = sin;
	smb_msg.msg_namelen = sizeof (struct sockaddr);
	smb_msg.msg_control = NULL;
	smb_msg.msg_controllen = 0;
	smb_msg.msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; /* BB add more flags?*/

	/* smb header is converted in header_assemble. bcc and rest of SMB word
	   area, and byte area if necessary, is converted to littleendian in 
	   cifssmb.c and RFC1001 len is converted to bigendian in smb_send 
	   Flags2 is converted in SendReceive */

	smb_buffer->smb_buf_length = cpu_to_be32(smb_buffer->smb_buf_length);
	cFYI(1, ("Sending smb of length %d ", smb_buf_length));
	dump_smb(smb_buffer, len);

	while (len > 0) {
		rc = kernel_sendmsg(ssocket, &smb_msg, &iov, number_of_pages, 
				    len);
		if ((rc == -ENOSPC) || (rc == -EAGAIN)) {
			i++;
			if(i > 60) {
				cERROR(1,
				   ("sends on sock %p stuck for 30 seconds",
				    ssocket));
				rc = -EAGAIN;
				break;
			}
			msleep(500);
			continue;
		}
		if (rc < 0) 
			break;
		iov.iov_base += rc;
		iov.iov_len -= rc;
		len -= rc;
	}

	if (rc < 0) {
		cERROR(1,("Error %d sending data on socket to server.", rc));
	} else {
		rc = 0;
	}

	return rc;
}


int
CIFSSendRcv(const unsigned int xid, struct cifsSesInfo *ses,
	    struct smb_hdr *in_buf, struct kvec * write_vector /* page list */, int *pbytes_returned, const int long_op)
{
	int rc = 0;
	unsigned long timeout = 15 * HZ;
	struct mid_q_entry *midQ = NULL;

	if (ses == NULL) {
		cERROR(1,("Null smb session"));
		return -EIO;
	}
	if(ses->server == NULL) {
		cERROR(1,("Null tcp session"));
		return -EIO;
	}
	if(pbytes_returned == NULL)
		return -EIO;
	else
		*pbytes_returned = 0;

  
	if(ses->server->tcpStatus == CIFS_EXITING)
		return -ENOENT;

	/* Ensure that we do not send more than 50 overlapping requests 
	   to the same server. We may make this configurable later or
	   use ses->maxReq */
	if(long_op == -1) {
		/* oplock breaks must not be held up */
		atomic_inc(&ses->server->inFlight);
	} else {
		spin_lock(&GlobalMid_Lock); 
		while(1) {        
			if(atomic_read(&ses->server->inFlight) >= cifs_max_pending){
				spin_unlock(&GlobalMid_Lock);
				wait_event(ses->server->request_q,
					atomic_read(&ses->server->inFlight)
					 < cifs_max_pending);
				spin_lock(&GlobalMid_Lock);
			} else {
				if(ses->server->tcpStatus == CifsExiting) {
					spin_unlock(&GlobalMid_Lock);
					return -ENOENT;
				}

			/* can not count locking commands against total since
			   they are allowed to block on server */
					
				if(long_op < 3) {
				/* update # of requests on the wire to server */
					atomic_inc(&ses->server->inFlight);
				}
				spin_unlock(&GlobalMid_Lock);
				break;
			}
		}
	}
	/* make sure that we sign in the same order that we send on this socket 
	   and avoid races inside tcp sendmsg code that could cause corruption
	   of smb data */

	down(&ses->server->tcpSem); 

	if (ses->server->tcpStatus == CifsExiting) {
		rc = -ENOENT;
		goto cifs_out_label;
	} else if (ses->server->tcpStatus == CifsNeedReconnect) {
		cFYI(1,("tcp session dead - return to caller to retry"));
		rc = -EAGAIN;
		goto cifs_out_label;
	} else if (ses->status != CifsGood) {
		/* check if SMB session is bad because we are setting it up */
		if((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) && 
			(in_buf->Command != SMB_COM_NEGOTIATE)) {
			rc = -EAGAIN;
			goto cifs_out_label;
		} /* else ok - we are setting up session */
	}
	midQ = AllocMidQEntry(in_buf, ses);
	if (midQ == NULL) {
		up(&ses->server->tcpSem);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return -ENOMEM;
	}

	if (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
		up(&ses->server->tcpSem);
		cERROR(1,
		       ("Illegal length, greater than maximum frame, %d ",
			in_buf->smb_buf_length));
		DeleteMidQEntry(midQ);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return -EIO;
	}

	/* BB can we sign efficiently in this path? */
	rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);

	midQ->midState = MID_REQUEST_SUBMITTED;
/*	rc = smb_sendv(ses->server->ssocket, in_buf, in_buf->smb_buf_length,
		       piovec, 
		       (struct sockaddr *) &(ses->server->addr.sockAddr));*/
	if(rc < 0) {
		DeleteMidQEntry(midQ);
		up(&ses->server->tcpSem);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return rc;
	} else
		up(&ses->server->tcpSem);
cifs_out_label:
	if(midQ)
	        DeleteMidQEntry(midQ);
                                                                                                                           
	if(long_op < 3) {
		atomic_dec(&ses->server->inFlight);
		wake_up(&ses->server->request_q);
	}

	return rc;
}


#endif /* CIFS_EXPERIMENTAL */

int
SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
	    struct smb_hdr *in_buf, struct smb_hdr *out_buf,
	    int *pbytes_returned, const int long_op)
{
	int rc = 0;
	unsigned int receive_len;
	unsigned long timeout;
	struct mid_q_entry *midQ;

	if (ses == NULL) {
		cERROR(1,("Null smb session"));
		return -EIO;
	}
	if(ses->server == NULL) {
		cERROR(1,("Null tcp session"));
		return -EIO;
	}

	if(ses->server->tcpStatus == CifsExiting)
		return -ENOENT;

	/* Ensure that we do not send more than 50 overlapping requests 
	   to the same server. We may make this configurable later or
	   use ses->maxReq */
	if(long_op == -1) {
		/* oplock breaks must not be held up */
		atomic_inc(&ses->server->inFlight);
	} else {
		spin_lock(&GlobalMid_Lock); 
		while(1) {        
			if(atomic_read(&ses->server->inFlight) >= 
					cifs_max_pending){
				spin_unlock(&GlobalMid_Lock);
				wait_event(ses->server->request_q,
					atomic_read(&ses->server->inFlight)
					 < cifs_max_pending);
				spin_lock(&GlobalMid_Lock);
			} else {
				if(ses->server->tcpStatus == CifsExiting) {
					spin_unlock(&GlobalMid_Lock);
					return -ENOENT;
				}

			/* can not count locking commands against total since
			   they are allowed to block on server */
					
				if(long_op < 3) {
				/* update # of requests on the wire to server */
					atomic_inc(&ses->server->inFlight);
				}
				spin_unlock(&GlobalMid_Lock);
				break;
			}
		}
	}
	/* make sure that we sign in the same order that we send on this socket 
	   and avoid races inside tcp sendmsg code that could cause corruption
	   of smb data */

	down(&ses->server->tcpSem); 

	if (ses->server->tcpStatus == CifsExiting) {
		rc = -ENOENT;
		goto out_unlock;
	} else if (ses->server->tcpStatus == CifsNeedReconnect) {
		cFYI(1,("tcp session dead - return to caller to retry"));
		rc = -EAGAIN;
		goto out_unlock;
	} else if (ses->status != CifsGood) {
		/* check if SMB session is bad because we are setting it up */
		if((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) && 
			(in_buf->Command != SMB_COM_NEGOTIATE)) {
			rc = -EAGAIN;
			goto out_unlock;
		} /* else ok - we are setting up session */
	}
	midQ = AllocMidQEntry(in_buf, ses);
	if (midQ == NULL) {
		up(&ses->server->tcpSem);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return -ENOMEM;
	}

	if (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
		up(&ses->server->tcpSem);
		cERROR(1,
		       ("Illegal length, greater than maximum frame, %d ",
			in_buf->smb_buf_length));
		DeleteMidQEntry(midQ);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return -EIO;
	}

	rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);

	midQ->midState = MID_REQUEST_SUBMITTED;
	rc = smb_send(ses->server->ssocket, in_buf, in_buf->smb_buf_length,
		      (struct sockaddr *) &(ses->server->addr.sockAddr));
	if(rc < 0) {
		DeleteMidQEntry(midQ);
		up(&ses->server->tcpSem);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return rc;
	} else
		up(&ses->server->tcpSem);
	if (long_op == -1)
		goto cifs_no_response_exit;
	else if (long_op == 2) /* writes past end of file can take loong time */
		timeout = 300 * HZ;
	else if (long_op == 1)
		timeout = 45 * HZ; /* should be greater than 
			servers oplock break timeout (about 43 seconds) */
	else if (long_op > 2) {
		timeout = MAX_SCHEDULE_TIMEOUT;
	} else
		timeout = 15 * HZ;
	/* wait for 15 seconds or until woken up due to response arriving or 
	   due to last connection to this server being unmounted */
	if (signal_pending(current)) {
		/* if signal pending do not hold up user for full smb timeout
		but we still give response a change to complete */
		timeout = 2 * HZ;
	}   

	/* No user interrupts in wait - wreaks havoc with performance */
	if(timeout != MAX_SCHEDULE_TIMEOUT) {
		timeout += jiffies;
		wait_event(ses->server->response_q,
			(!(midQ->midState & MID_REQUEST_SUBMITTED)) || 
			time_after(jiffies, timeout) || 
			((ses->server->tcpStatus != CifsGood) &&
			 (ses->server->tcpStatus != CifsNew)));
	} else {
		wait_event(ses->server->response_q,
			(!(midQ->midState & MID_REQUEST_SUBMITTED)) || 
			((ses->server->tcpStatus != CifsGood) &&
			 (ses->server->tcpStatus != CifsNew)));
	}

	spin_lock(&GlobalMid_Lock);
	if (midQ->resp_buf) {
		spin_unlock(&GlobalMid_Lock);
		receive_len = be32_to_cpu(*(__be32 *)midQ->resp_buf);
	} else {
		cERROR(1,("No response buffer"));
		if(midQ->midState == MID_REQUEST_SUBMITTED) {
			if(ses->server->tcpStatus == CifsExiting)
				rc = -EHOSTDOWN;
			else {
				ses->server->tcpStatus = CifsNeedReconnect;
				midQ->midState = MID_RETRY_NEEDED;
			}
		}

		if (rc != -EHOSTDOWN) {
			if(midQ->midState == MID_RETRY_NEEDED) {
				rc = -EAGAIN;
				cFYI(1,("marking request for retry"));
			} else {
				rc = -EIO;
			}
		}
		spin_unlock(&GlobalMid_Lock);
		DeleteMidQEntry(midQ);
		/* If not lock req, update # of requests on wire to server */
		if(long_op < 3) {
			atomic_dec(&ses->server->inFlight); 
			wake_up(&ses->server->request_q);
		}
		return rc;
	}
  
	if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) {
		cERROR(1, ("Frame too large received.  Length: %d  Xid: %d",
			receive_len, xid));
		rc = -EIO;
	} else {		/* rcvd frame is ok */

		if (midQ->resp_buf && out_buf
		    && (midQ->midState == MID_RESPONSE_RECEIVED)) {
			out_buf->smb_buf_length = receive_len;
			memcpy((char *)out_buf + 4,
			       (char *)midQ->resp_buf + 4,
			       receive_len);

			dump_smb(out_buf, 92);
			/* convert the length into a more usable form */
			if((receive_len > 24) &&
			   (ses->server->secMode & (SECMODE_SIGN_REQUIRED |
					SECMODE_SIGN_ENABLED))) {
				rc = cifs_verify_signature(out_buf,
						ses->server->mac_signing_key,
						midQ->sequence_number+1);
				if(rc) {
					cERROR(1,("Unexpected SMB signature"));
					/* BB FIXME add code to kill session */
				}
			}

			*pbytes_returned = out_buf->smb_buf_length;

			/* BB special case reconnect tid and uid here? */
			rc = map_smb_to_linux_error(out_buf);

			/* convert ByteCount if necessary */
			if (receive_len >=
			    sizeof (struct smb_hdr) -
			    4 /* do not count RFC1001 header */  +
			    (2 * out_buf->WordCount) + 2 /* bcc */ )
				BCC(out_buf) = le16_to_cpu(BCC(out_buf));
		} else {
			rc = -EIO;
			cFYI(1,("Bad MID state? "));
		}
	}
cifs_no_response_exit:
	DeleteMidQEntry(midQ);

	if(long_op < 3) {
		atomic_dec(&ses->server->inFlight); 
		wake_up(&ses->server->request_q);
	}

	return rc;

out_unlock:
	up(&ses->server->tcpSem);
	/* If not lock req, update # of requests on wire to server */
	if(long_op < 3) {
		atomic_dec(&ses->server->inFlight); 
		wake_up(&ses->server->request_q);
	}

	return rc;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* fs/cifs/transport.c
	3	*
b8643e1b	4	* Copyright (C) International Business Machines Corp., 2002,2005
1da177e4 LT	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/fs.h>
	23	#include <linux/list.h>
	24	#include <linux/wait.h>
	25	#include <linux/net.h>
	26	#include <linux/delay.h>
	27	#include <asm/uaccess.h>
	28	#include <asm/processor.h>
	29	#include <linux/mempool.h>
	30	#include "cifspdu.h"
	31	#include "cifsglob.h"
	32	#include "cifsproto.h"
	33	#include "cifs_debug.h"
	34
	35	extern mempool_t *cifs_mid_poolp;
	36	extern kmem_cache_t *cifs_oplock_cachep;
	37
	38	static struct mid_q_entry *
	39	AllocMidQEntry(struct smb_hdr smb_buffer, struct cifsSesInfo ses)
	40	{
	41	struct mid_q_entry *temp;
	42
	43	if (ses == NULL) {
275cde1a	44	cERROR(1, ("Null session passed in to AllocMidQEntry"));
1da177e4 LT	45	return NULL;
	46	}
	47	if (ses->server == NULL) {
	48	cERROR(1, ("Null TCP session in AllocMidQEntry"));
	49	return NULL;
	50	}
	51
	52	temp = (struct mid_q_entry *) mempool_alloc(cifs_mid_poolp,SLAB_KERNEL \| SLAB_NOFS);
	53	if (temp == NULL)
	54	return temp;
	55	else {
	56	memset(temp, 0, sizeof (struct mid_q_entry));
	57	temp->mid = smb_buffer->Mid; /* always LE */
	58	temp->pid = current->pid;
	59	temp->command = smb_buffer->Command;
	60	cFYI(1, ("For smb_command %d", temp->command));
	61	do_gettimeofday(&temp->when_sent);
	62	temp->ses = ses;
	63	temp->tsk = current;
	64	}
	65
	66	spin_lock(&GlobalMid_Lock);
	67	list_add_tail(&temp->qhead, &ses->server->pending_mid_q);
	68	atomic_inc(&midCount);
	69	temp->midState = MID_REQUEST_ALLOCATED;
	70	spin_unlock(&GlobalMid_Lock);
	71	return temp;
	72	}
	73
	74	static void
	75	DeleteMidQEntry(struct mid_q_entry *midEntry)
	76	{
	77	spin_lock(&GlobalMid_Lock);
	78	midEntry->midState = MID_FREE;
	79	list_del(&midEntry->qhead);
	80	atomic_dec(&midCount);
	81	spin_unlock(&GlobalMid_Lock);
b8643e1b SF	82	if(midEntry->largeBuf)
	83	cifs_buf_release(midEntry->resp_buf);
	84	else
	85	cifs_small_buf_release(midEntry->resp_buf);
1da177e4 LT	86	mempool_free(midEntry, cifs_mid_poolp);
	87	}
	88
	89	struct oplock_q_entry *
	90	AllocOplockQEntry(struct inode * pinode, __u16 fid, struct cifsTconInfo * tcon)
	91	{
	92	struct oplock_q_entry *temp;
	93	if ((pinode== NULL) \|\| (tcon == NULL)) {
	94	cERROR(1, ("Null parms passed to AllocOplockQEntry"));
	95	return NULL;
	96	}
	97	temp = (struct oplock_q_entry *) kmem_cache_alloc(cifs_oplock_cachep,
	98	SLAB_KERNEL);
	99	if (temp == NULL)
	100	return temp;
	101	else {
	102	temp->pinode = pinode;
	103	temp->tcon = tcon;
	104	temp->netfid = fid;
	105	spin_lock(&GlobalMid_Lock);
	106	list_add_tail(&temp->qhead, &GlobalOplock_Q);
	107	spin_unlock(&GlobalMid_Lock);
	108	}
	109	return temp;
	110
	111	}
	112
	113	void DeleteOplockQEntry(struct oplock_q_entry * oplockEntry)
	114	{
	115	spin_lock(&GlobalMid_Lock);
	116	/* should we check if list empty first? */
	117	list_del(&oplockEntry->qhead);
	118	spin_unlock(&GlobalMid_Lock);
	119	kmem_cache_free(cifs_oplock_cachep, oplockEntry);
	120	}
	121
	122	int
	123	smb_send(struct socket ssocket, struct smb_hdr smb_buffer,
	124	unsigned int smb_buf_length, struct sockaddr *sin)
	125	{
	126	int rc = 0;
	127	int i = 0;
	128	struct msghdr smb_msg;
	129	struct kvec iov;
	130	unsigned len = smb_buf_length + 4;
	131
	132	if(ssocket == NULL)
	133	return -ENOTSOCK; /* BB eventually add reconnect code here */
	134	iov.iov_base = smb_buffer;
	135	iov.iov_len = len;
	136
	137	smb_msg.msg_name = sin;
	138	smb_msg.msg_namelen = sizeof (struct sockaddr);
	139	smb_msg.msg_control = NULL;
	140	smb_msg.msg_controllen = 0;
	141	smb_msg.msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; /* BB add more flags?*/
	142
	143	/* smb header is converted in header_assemble. bcc and rest of SMB word
	144	area, and byte area if necessary, is converted to littleendian in
	145	cifssmb.c and RFC1001 len is converted to bigendian in smb_send
	146	Flags2 is converted in SendReceive */
	147
	148	smb_buffer->smb_buf_length = cpu_to_be32(smb_buffer->smb_buf_length);
	149	cFYI(1, ("Sending smb of length %d ", smb_buf_length));
150	dump_smb(smb_buffer, len);
151
152	while (len > 0) {
153	rc = kernel_sendmsg(ssocket, &smb_msg, &iov, 1, len);
154	if ((rc == -ENOSPC) \|\| (rc == -EAGAIN)) {
155	i++;
156	if(i > 60) {
157	cERROR(1,
158	("sends on sock %p stuck for 30 seconds",
159	ssocket));
160	rc = -EAGAIN;
161	break;
162	}
163	msleep(500);
164	continue;
165	}
166	if (rc < 0)
167	break;
168	iov.iov_base += rc;
169	iov.iov_len -= rc;
170	len -= rc;
171	}
172
173	if (rc < 0) {
174	cERROR(1,("Error %d sending data on socket to server.", rc));
175	} else {
176	rc = 0;
177	}
178
179	return rc;
180	}
181
182	#ifdef CIFS_EXPERIMENTAL
183	/* BB finish off this function, adding support for writing set of pages as iovec */
184	/* and also adding support for operations that need to parse the response smb */
185
186	int
187	smb_sendv(struct socket ssocket, struct smb_hdr smb_buffer,
275cde1a SF	188	unsigned int smb_buf_length, struct kvec * write_vector
275cde1a SF	189	/* page list /, struct sockaddr sin)
1da177e4 LT	190	{
	191	int rc = 0;
	192	int i = 0;
	193	struct msghdr smb_msg;
	194	number_of_pages += 1; /* account for SMB header */
	195	struct kvec * piov = kmalloc(number_of_pages * sizeof(struct kvec));
1da177e4 LT	196	unsigned len = smb_buf_length + 4;
	197
	198	if(ssocket == NULL)
	199	return -ENOTSOCK; /* BB eventually add reconnect code here */
	200	iov.iov_base = smb_buffer;
	201	iov.iov_len = len;
	202
	203	smb_msg.msg_name = sin;
	204	smb_msg.msg_namelen = sizeof (struct sockaddr);
	205	smb_msg.msg_control = NULL;
	206	smb_msg.msg_controllen = 0;
	207	smb_msg.msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL; /* BB add more flags?*/
	208
	209	/* smb header is converted in header_assemble. bcc and rest of SMB word
	210	area, and byte area if necessary, is converted to littleendian in
	211	cifssmb.c and RFC1001 len is converted to bigendian in smb_send
	212	Flags2 is converted in SendReceive */
	213
	214	smb_buffer->smb_buf_length = cpu_to_be32(smb_buffer->smb_buf_length);
	215	cFYI(1, ("Sending smb of length %d ", smb_buf_length));
	216	dump_smb(smb_buffer, len);
	217
	218	while (len > 0) {
275cde1a SF	219	rc = kernel_sendmsg(ssocket, &smb_msg, &iov, number_of_pages,
275cde1a SF	220	len);
1da177e4 LT	221	if ((rc == -ENOSPC) \|\| (rc == -EAGAIN)) {
	222	i++;
	223	if(i > 60) {
	224	cERROR(1,
	225	("sends on sock %p stuck for 30 seconds",
	226	ssocket));
	227	rc = -EAGAIN;
	228	break;
	229	}
	230	msleep(500);
	231	continue;
	232	}
	233	if (rc < 0)
	234	break;
	235	iov.iov_base += rc;
	236	iov.iov_len -= rc;
	237	len -= rc;
	238	}
	239
	240	if (rc < 0) {
	241	cERROR(1,("Error %d sending data on socket to server.", rc));
	242	} else {
	243	rc = 0;
	244	}
	245
	246	return rc;
	247	}
	248
	249
	250	int
	251	CIFSSendRcv(const unsigned int xid, struct cifsSesInfo *ses,
	252	struct smb_hdr in_buf, struct kvec write_vector /* page list /, int pbytes_returned, const int long_op)
	253	{
	254	int rc = 0;
	255	unsigned long timeout = 15 * HZ;
	256	struct mid_q_entry *midQ = NULL;
	257
	258	if (ses == NULL) {
	259	cERROR(1,("Null smb session"));
	260	return -EIO;
	261	}
	262	if(ses->server == NULL) {
	263	cERROR(1,("Null tcp session"));
	264	return -EIO;
	265	}
	266	if(pbytes_returned == NULL)
	267	return -EIO;
	268	else
	269	*pbytes_returned = 0;
	270
	271
	272
31ca3bc3 SF	273	if(ses->server->tcpStatus == CIFS_EXITING)
	274	return -ENOENT;
	275
1da177e4 LT	276	/* Ensure that we do not send more than 50 overlapping requests
	277	to the same server. We may make this configurable later or
	278	use ses->maxReq */
	279	if(long_op == -1) {
	280	/* oplock breaks must not be held up */
	281	atomic_inc(&ses->server->inFlight);
	282	} else {
	283	spin_lock(&GlobalMid_Lock);
	284	while(1) {
	285	if(atomic_read(&ses->server->inFlight) >= cifs_max_pending){
	286	spin_unlock(&GlobalMid_Lock);
	287	wait_event(ses->server->request_q,
	288	atomic_read(&ses->server->inFlight)
	289	< cifs_max_pending);
	290	spin_lock(&GlobalMid_Lock);
	291	} else {
	292	if(ses->server->tcpStatus == CifsExiting) {
	293	spin_unlock(&GlobalMid_Lock);
	294	return -ENOENT;
	295	}
	296
	297	/* can not count locking commands against total since
	298	they are allowed to block on server */
	299
	300	if(long_op < 3) {
	301	/* update # of requests on the wire to server */
	302	atomic_inc(&ses->server->inFlight);
	303	}
	304	spin_unlock(&GlobalMid_Lock);
	305	break;
	306	}
	307	}
	308	}
	309	/* make sure that we sign in the same order that we send on this socket
	310	and avoid races inside tcp sendmsg code that could cause corruption
	311	of smb data */
	312
	313	down(&ses->server->tcpSem);
	314
	315	if (ses->server->tcpStatus == CifsExiting) {
	316	rc = -ENOENT;
	317	goto cifs_out_label;
	318	} else if (ses->server->tcpStatus == CifsNeedReconnect) {
	319	cFYI(1,("tcp session dead - return to caller to retry"));
	320	rc = -EAGAIN;
	321	goto cifs_out_label;
	322	} else if (ses->status != CifsGood) {
	323	/* check if SMB session is bad because we are setting it up */
	324	if((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
	325	(in_buf->Command != SMB_COM_NEGOTIATE)) {
	326	rc = -EAGAIN;
	327	goto cifs_out_label;
	328	} /* else ok - we are setting up session */
	329	}
	330	midQ = AllocMidQEntry(in_buf, ses);
	331	if (midQ == NULL) {
	332	up(&ses->server->tcpSem);
	333	/* If not lock req, update # of requests on wire to server */
	334	if(long_op < 3) {
	335	atomic_dec(&ses->server->inFlight);
	336	wake_up(&ses->server->request_q);
	337	}
	338	return -ENOMEM;
	339	}
340
341	if (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
342	up(&ses->server->tcpSem);
343	cERROR(1,
344	("Illegal length, greater than maximum frame, %d ",
345	in_buf->smb_buf_length));
346	DeleteMidQEntry(midQ);
347	/* If not lock req, update # of requests on wire to server */
348	if(long_op < 3) {
349	atomic_dec(&ses->server->inFlight);
350	wake_up(&ses->server->request_q);
351	}
352	return -EIO;
353	}
354
355	/* BB can we sign efficiently in this path? */
ad009ac9	356	rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1da177e4 LT	357
1da177e4 LT	358	midQ->midState = MID_REQUEST_SUBMITTED;
275cde1a SF	359	/* rc = smb_sendv(ses->server->ssocket, in_buf, in_buf->smb_buf_length,
	360	piovec,
	361	(struct sockaddr ) &(ses->server->addr.sockAddr));/
1da177e4 LT	362	if(rc < 0) {
	363	DeleteMidQEntry(midQ);
	364	up(&ses->server->tcpSem);
	365	/* If not lock req, update # of requests on wire to server */
	366	if(long_op < 3) {
	367	atomic_dec(&ses->server->inFlight);
	368	wake_up(&ses->server->request_q);
	369	}
	370	return rc;
	371	} else
	372	up(&ses->server->tcpSem);
	373	cifs_out_label:
	374	if(midQ)
	375	DeleteMidQEntry(midQ);
	376
	377	if(long_op < 3) {
	378	atomic_dec(&ses->server->inFlight);
	379	wake_up(&ses->server->request_q);
	380	}
	381
	382	return rc;
	383	}
	384
	385
	386	#endif /* CIFS_EXPERIMENTAL */
	387
	388	int
	389	SendReceive(const unsigned int xid, struct cifsSesInfo *ses,
	390	struct smb_hdr in_buf, struct smb_hdr out_buf,
	391	int *pbytes_returned, const int long_op)
	392	{
	393	int rc = 0;
	394	unsigned int receive_len;
	395	unsigned long timeout;
	396	struct mid_q_entry *midQ;
	397
	398	if (ses == NULL) {
	399	cERROR(1,("Null smb session"));
	400	return -EIO;
	401	}
	402	if(ses->server == NULL) {
	403	cERROR(1,("Null tcp session"));
	404	return -EIO;
	405	}
	406
31ca3bc3 SF	407	if(ses->server->tcpStatus == CifsExiting)
	408	return -ENOENT;
	409
1da177e4 LT	410	/* Ensure that we do not send more than 50 overlapping requests
	411	to the same server. We may make this configurable later or
	412	use ses->maxReq */
	413	if(long_op == -1) {
	414	/* oplock breaks must not be held up */
	415	atomic_inc(&ses->server->inFlight);
	416	} else {
	417	spin_lock(&GlobalMid_Lock);
	418	while(1) {
275cde1a SF	419	if(atomic_read(&ses->server->inFlight) >=
275cde1a SF	420	cifs_max_pending){
1da177e4 LT	421	spin_unlock(&GlobalMid_Lock);
	422	wait_event(ses->server->request_q,
	423	atomic_read(&ses->server->inFlight)
	424	< cifs_max_pending);
	425	spin_lock(&GlobalMid_Lock);
	426	} else {
	427	if(ses->server->tcpStatus == CifsExiting) {
	428	spin_unlock(&GlobalMid_Lock);
	429	return -ENOENT;
	430	}
	431
	432	/* can not count locking commands against total since
	433	they are allowed to block on server */
	434
	435	if(long_op < 3) {
	436	/* update # of requests on the wire to server */
	437	atomic_inc(&ses->server->inFlight);
	438	}
	439	spin_unlock(&GlobalMid_Lock);
	440	break;
	441	}
	442	}
	443	}
	444	/* make sure that we sign in the same order that we send on this socket
	445	and avoid races inside tcp sendmsg code that could cause corruption
	446	of smb data */
	447
	448	down(&ses->server->tcpSem);
	449
	450	if (ses->server->tcpStatus == CifsExiting) {
	451	rc = -ENOENT;
	452	goto out_unlock;
	453	} else if (ses->server->tcpStatus == CifsNeedReconnect) {
	454	cFYI(1,("tcp session dead - return to caller to retry"));
	455	rc = -EAGAIN;
	456	goto out_unlock;
	457	} else if (ses->status != CifsGood) {
	458	/* check if SMB session is bad because we are setting it up */
	459	if((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
	460	(in_buf->Command != SMB_COM_NEGOTIATE)) {
	461	rc = -EAGAIN;
	462	goto out_unlock;
	463	} /* else ok - we are setting up session */
	464	}
	465	midQ = AllocMidQEntry(in_buf, ses);
	466	if (midQ == NULL) {
	467	up(&ses->server->tcpSem);
	468	/* If not lock req, update # of requests on wire to server */
	469	if(long_op < 3) {
	470	atomic_dec(&ses->server->inFlight);
	471	wake_up(&ses->server->request_q);
	472	}
	473	return -ENOMEM;
	474	}
	475
	476	if (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
	477	up(&ses->server->tcpSem);
	478	cERROR(1,
	479	("Illegal length, greater than maximum frame, %d ",
	480	in_buf->smb_buf_length));
	481	DeleteMidQEntry(midQ);
	482	/* If not lock req, update # of requests on wire to server */
	483	if(long_op < 3) {
	484	atomic_dec(&ses->server->inFlight);
485	wake_up(&ses->server->request_q);
486	}
487	return -EIO;
488	}
489
ad009ac9	490	rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1da177e4 LT	491
	492	midQ->midState = MID_REQUEST_SUBMITTED;
	493	rc = smb_send(ses->server->ssocket, in_buf, in_buf->smb_buf_length,
	494	(struct sockaddr *) &(ses->server->addr.sockAddr));
	495	if(rc < 0) {
	496	DeleteMidQEntry(midQ);
	497	up(&ses->server->tcpSem);
	498	/* If not lock req, update # of requests on wire to server */
	499	if(long_op < 3) {
	500	atomic_dec(&ses->server->inFlight);
	501	wake_up(&ses->server->request_q);
	502	}
	503	return rc;
	504	} else
	505	up(&ses->server->tcpSem);
	506	if (long_op == -1)
	507	goto cifs_no_response_exit;
275cde1a	508	else if (long_op == 2) /* writes past end of file can take loong time */
1da177e4 LT	509	timeout = 300 * HZ;
	510	else if (long_op == 1)
	511	timeout = 45 * HZ; /* should be greater than
	512	servers oplock break timeout (about 43 seconds) */
	513	else if (long_op > 2) {
	514	timeout = MAX_SCHEDULE_TIMEOUT;
	515	} else
	516	timeout = 15 * HZ;
	517	/* wait for 15 seconds or until woken up due to response arriving or
	518	due to last connection to this server being unmounted */
	519	if (signal_pending(current)) {
	520	/* if signal pending do not hold up user for full smb timeout
	521	but we still give response a change to complete */
	522	timeout = 2 * HZ;
	523	}
	524
	525	/* No user interrupts in wait - wreaks havoc with performance */
	526	if(timeout != MAX_SCHEDULE_TIMEOUT) {
	527	timeout += jiffies;
	528	wait_event(ses->server->response_q,
	529	(!(midQ->midState & MID_REQUEST_SUBMITTED)) \|\|
	530	time_after(jiffies, timeout) \|\|
	531	((ses->server->tcpStatus != CifsGood) &&
	532	(ses->server->tcpStatus != CifsNew)));
	533	} else {
	534	wait_event(ses->server->response_q,
	535	(!(midQ->midState & MID_REQUEST_SUBMITTED)) \|\|
	536	((ses->server->tcpStatus != CifsGood) &&
	537	(ses->server->tcpStatus != CifsNew)));
	538	}
	539
	540	spin_lock(&GlobalMid_Lock);
	541	if (midQ->resp_buf) {
	542	spin_unlock(&GlobalMid_Lock);
	543	receive_len = be32_to_cpu((__be32 )midQ->resp_buf);
	544	} else {
	545	cERROR(1,("No response buffer"));
	546	if(midQ->midState == MID_REQUEST_SUBMITTED) {
	547	if(ses->server->tcpStatus == CifsExiting)
	548	rc = -EHOSTDOWN;
	549	else {
	550	ses->server->tcpStatus = CifsNeedReconnect;
	551	midQ->midState = MID_RETRY_NEEDED;
	552	}
	553	}
	554
	555	if (rc != -EHOSTDOWN) {
	556	if(midQ->midState == MID_RETRY_NEEDED) {
	557	rc = -EAGAIN;
	558	cFYI(1,("marking request for retry"));
	559	} else {
	560	rc = -EIO;
	561	}
	562	}
	563	spin_unlock(&GlobalMid_Lock);
	564	DeleteMidQEntry(midQ);
	565	/* If not lock req, update # of requests on wire to server */
	566	if(long_op < 3) {
	567	atomic_dec(&ses->server->inFlight);
	568	wake_up(&ses->server->request_q);
	569	}
	570	return rc;
	571	}
	572
573	if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) {
ad009ac9	574	cERROR(1, ("Frame too large received. Length: %d Xid: %d",
1da177e4 LT	575	receive_len, xid));
	576	rc = -EIO;
	577	} else { /* rcvd frame is ok */
	578
	579	if (midQ->resp_buf && out_buf
	580	&& (midQ->midState == MID_RESPONSE_RECEIVED)) {
	581	out_buf->smb_buf_length = receive_len;
	582	memcpy((char *)out_buf + 4,
	583	(char *)midQ->resp_buf + 4,
	584	receive_len);
	585
	586	dump_smb(out_buf, 92);
	587	/* convert the length into a more usable form */
	588	if((receive_len > 24) &&
ad009ac9 SF	589	(ses->server->secMode & (SECMODE_SIGN_REQUIRED \|
	590	SECMODE_SIGN_ENABLED))) {
	591	rc = cifs_verify_signature(out_buf,
	592	ses->server->mac_signing_key,
	593	midQ->sequence_number+1);
	594	if(rc) {
275cde1a SF	595	cERROR(1,("Unexpected SMB signature"));
275cde1a SF	596	/* BB FIXME add code to kill session */
ad009ac9	597	}
1da177e4 LT	598	}
	599
	600	*pbytes_returned = out_buf->smb_buf_length;
	601
ad009ac9	602	/* BB special case reconnect tid and uid here? */
1da177e4 LT	603	rc = map_smb_to_linux_error(out_buf);
	604
	605	/* convert ByteCount if necessary */
	606	if (receive_len >=
	607	sizeof (struct smb_hdr) -
	608	4 /* do not count RFC1001 header */ +
	609	(2 * out_buf->WordCount) + 2 /* bcc */ )
	610	BCC(out_buf) = le16_to_cpu(BCC(out_buf));
	611	} else {
	612	rc = -EIO;
	613	cFYI(1,("Bad MID state? "));
	614	}
	615	}
	616	cifs_no_response_exit:
	617	DeleteMidQEntry(midQ);
	618
	619	if(long_op < 3) {
	620	atomic_dec(&ses->server->inFlight);
	621	wake_up(&ses->server->request_q);
	622	}
	623
	624	return rc;
	625
	626	out_unlock:
	627	up(&ses->server->tcpSem);
	628	/* If not lock req, update # of requests on wire to server */
	629	if(long_op < 3) {
	630	atomic_dec(&ses->server->inFlight);
	631	wake_up(&ses->server->request_q);
	632	}
	633
	634	return rc;
	635	}