/*
* fs/cifs/transport.c
*
* Copyright (C) International Business Machines Corp., 2002,2004
* 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 <asm/uaccess.h>
#include <asm/processor.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
extern kmem_cache_t *cifs_mid_cachep;
extern kmem_cache_t *cifs_oplock_cachep;
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 *) kmem_cache_alloc(cifs_mid_cachep,
SLAB_KERNEL);
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;
}
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);
cifs_buf_release(midEntry->resp_buf);
kmem_cache_free(cifs_mid_cachep, midEntry);
}
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;
struct msghdr smb_msg;
struct iovec iov;
mm_segment_t temp_fs;
if(ssocket == NULL)
return -ENOTSOCK; /* BB eventually add reconnect code here */
/* ssocket->sk->allocation = GFP_BUFFER; *//* BB is this spurious? */
iov.iov_base = smb_buffer;
iov.iov_len = smb_buf_length + 4;
smb_msg.msg_name = sin;
smb_msg.msg_namelen = sizeof (struct sockaddr);
smb_msg.msg_iov = &iov;
smb_msg.msg_iovlen = 1;
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, smb_buf_length + 4);
temp_fs = get_fs(); /* we must turn off socket api parm checking */
set_fs(get_ds());
while(iov.iov_len > 0) {
rc = sock_sendmsg(ssocket, &smb_msg, smb_buf_length + 4);
if ((rc == -ENOSPC) || (rc == -EAGAIN)) {
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ/2);
continue;
}
if (rc < 0)
break;
iov.iov_base += rc;
iov.iov_len -= rc;
}
set_fs(temp_fs);
if (rc < 0) {
cERROR(1,("Error %d sending data on socket to server.", rc));
} else {
rc = 0;
}
return rc;
}
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;
long timeout;
struct mid_q_entry *midQ;
if ((ses == NULL) || (ses->server == NULL)) {
cERROR(1,("Null tcp session or smb session: %p",ses));
return -EIO;
}
if (ses->server->tcpStatus == CifsExiting) {
return -ENOENT;
} else if (ses->server->tcpStatus == CifsNeedReconnect) {
cFYI(1,("tcp session dead - return to caller to retry"));
return -EAGAIN;
} 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)) {
return -EAGAIN;
} /* else ok - we are setting up session */
}
/* 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);
midQ = AllocMidQEntry(in_buf, ses);
if (midQ == NULL) {
up(&ses->server->tcpSem);
return -EIO;
}
if (in_buf->smb_buf_length > CIFS_MAX_MSGSIZE + 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);
return -EIO;
}
if (in_buf->smb_buf_length > 12)
in_buf->Flags2 = cpu_to_le16(in_buf->Flags2);
rc = cifs_sign_smb(in_buf, ses, &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));
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 looooong 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 */
if(midQ->midState & MID_REQUEST_SUBMITTED) {
set_current_state(TASK_UNINTERRUPTIBLE);
timeout = sleep_on_timeout(&ses->server->response_q,2 * HZ);
}
} else { /* using normal timeout */
/* timeout = wait_event_interruptible_timeout(ses->server->response_q,
(midQ->midState & MID_RESPONSE_RECEIVED) ||
((ses->server->tcpStatus != CifsGood) &&
(ses->server->tcpStatus != CifsNew)),
timeout); */
/* Can not allow user interrupts- wreaks havoc with performance */
if(midQ->midState & MID_REQUEST_SUBMITTED) {
set_current_state(TASK_UNINTERRUPTIBLE);
timeout = sleep_on_timeout(&ses->server->response_q,timeout);
}
}
spin_lock(&GlobalMid_Lock);
if (midQ->resp_buf) {
spin_unlock(&GlobalMid_Lock);
receive_len = be32_to_cpu(midQ->resp_buf->smb_buf_length);
} 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);
return rc;
}
if (receive_len > CIFS_MAX_MSGSIZE + 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)) {
memcpy(out_buf, midQ->resp_buf,
receive_len +
4 /* include 4 byte RFC1001 header */ );
dump_smb(out_buf, 92);
/* convert the length into a more usable form */
out_buf->smb_buf_length =
be32_to_cpu(out_buf->smb_buf_length);
if((out_buf->smb_buf_length > 24) &&
(ses->server->secMode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))) {
rc = cifs_verify_signature(out_buf, ses->mac_signing_key,midQ->sequence_number); /* BB fix BB */
if(rc)
cFYI(1,("Unexpected signature received from server"));
}
if (out_buf->smb_buf_length > 12)
out_buf->Flags2 = le16_to_cpu(out_buf->Flags2);
if (out_buf->smb_buf_length > 28)
out_buf->Pid = le16_to_cpu(out_buf->Pid);
if (out_buf->smb_buf_length > 28)
out_buf->PidHigh =
le16_to_cpu(out_buf->PidHigh);
*pbytes_returned = out_buf->smb_buf_length;
/* BB special case reconnect tid and reconnect 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); /* BB what if process is killed?
- BB add background daemon to clean up Mid entries from
killed processes & test killing process with active mid */
return rc;
}