forked from Minki/linux
3bc303c254
This is the fourth respin of the patch to convert oplock breaks to use the slow_work facility. A customer of ours was testing a backport of one of the earlier patchsets, and hit a "Busy inodes after umount..." problem. An oplock break job had raced with a umount, and the superblock got torn down and its memory reused. When the oplock break job tried to dereference the inode->i_sb, the kernel oopsed. This patchset has the oplock break job hold an inode and vfsmount reference until the oplock break completes. With this, there should be no need to take a tcon reference (the vfsmount implicitly holds one already). Currently, when an oplock break comes in there's a chance that the oplock break job won't occur if the allocation of the oplock_q_entry fails. There are also some rather nasty races in the allocation and handling these structs. Rather than allocating oplock queue entries when an oplock break comes in, add a few extra fields to the cifsFileInfo struct. Get rid of the dedicated cifs_oplock_thread as well and queue the oplock break job to the slow_work thread pool. This approach also has the advantage that the oplock break jobs can potentially run in parallel rather than be serialized like they are today. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
1010 lines
27 KiB
C
1010 lines
27 KiB
C
/*
|
|
* fs/cifs/transport.c
|
|
*
|
|
* Copyright (C) International Business Machines Corp., 2002,2008
|
|
* Author(s): Steve French (sfrench@us.ibm.com)
|
|
* Jeremy Allison (jra@samba.org) 2006.
|
|
*
|
|
* 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 struct kmem_cache *cifs_oplock_cachep;
|
|
|
|
static struct mid_q_entry *
|
|
AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
|
|
{
|
|
struct mid_q_entry *temp;
|
|
|
|
if (server == NULL) {
|
|
cERROR(1, ("Null TCP session in AllocMidQEntry"));
|
|
return NULL;
|
|
}
|
|
|
|
temp = mempool_alloc(cifs_mid_poolp, GFP_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);*/ /* easier to use jiffies */
|
|
/* when mid allocated can be before when sent */
|
|
temp->when_alloc = jiffies;
|
|
temp->tsk = current;
|
|
}
|
|
|
|
spin_lock(&GlobalMid_Lock);
|
|
list_add_tail(&temp->qhead, &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)
|
|
{
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
unsigned long now;
|
|
#endif
|
|
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);
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
now = jiffies;
|
|
/* commands taking longer than one second are indications that
|
|
something is wrong, unless it is quite a slow link or server */
|
|
if ((now - midEntry->when_alloc) > HZ) {
|
|
if ((cifsFYI & CIFS_TIMER) &&
|
|
(midEntry->command != SMB_COM_LOCKING_ANDX)) {
|
|
printk(KERN_DEBUG " CIFS slow rsp: cmd %d mid %d",
|
|
midEntry->command, midEntry->mid);
|
|
printk(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
|
|
now - midEntry->when_alloc,
|
|
now - midEntry->when_sent,
|
|
now - midEntry->when_received);
|
|
}
|
|
}
|
|
#endif
|
|
mempool_free(midEntry, cifs_mid_poolp);
|
|
}
|
|
|
|
static int
|
|
smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
|
|
{
|
|
int rc = 0;
|
|
int i = 0;
|
|
struct msghdr smb_msg;
|
|
struct smb_hdr *smb_buffer = iov[0].iov_base;
|
|
unsigned int len = iov[0].iov_len;
|
|
unsigned int total_len;
|
|
int first_vec = 0;
|
|
unsigned int smb_buf_length = smb_buffer->smb_buf_length;
|
|
struct socket *ssocket = server->ssocket;
|
|
|
|
if (ssocket == NULL)
|
|
return -ENOTSOCK; /* BB eventually add reconnect code here */
|
|
|
|
smb_msg.msg_name = (struct sockaddr *) &server->addr.sockAddr;
|
|
smb_msg.msg_namelen = sizeof(struct sockaddr);
|
|
smb_msg.msg_control = NULL;
|
|
smb_msg.msg_controllen = 0;
|
|
if (server->noblocksnd)
|
|
smb_msg.msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL;
|
|
else
|
|
smb_msg.msg_flags = MSG_NOSIGNAL;
|
|
|
|
/* 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 */
|
|
|
|
|
|
total_len = 0;
|
|
for (i = 0; i < n_vec; i++)
|
|
total_len += iov[i].iov_len;
|
|
|
|
smb_buffer->smb_buf_length = cpu_to_be32(smb_buffer->smb_buf_length);
|
|
cFYI(1, ("Sending smb: total_len %d", total_len));
|
|
dump_smb(smb_buffer, len);
|
|
|
|
i = 0;
|
|
while (total_len) {
|
|
rc = kernel_sendmsg(ssocket, &smb_msg, &iov[first_vec],
|
|
n_vec - first_vec, total_len);
|
|
if ((rc == -ENOSPC) || (rc == -EAGAIN)) {
|
|
i++;
|
|
/* if blocking send we try 3 times, since each can block
|
|
for 5 seconds. For nonblocking we have to try more
|
|
but wait increasing amounts of time allowing time for
|
|
socket to clear. The overall time we wait in either
|
|
case to send on the socket is about 15 seconds.
|
|
Similarly we wait for 15 seconds for
|
|
a response from the server in SendReceive[2]
|
|
for the server to send a response back for
|
|
most types of requests (except SMB Write
|
|
past end of file which can be slow, and
|
|
blocking lock operations). NFS waits slightly longer
|
|
than CIFS, but this can make it take longer for
|
|
nonresponsive servers to be detected and 15 seconds
|
|
is more than enough time for modern networks to
|
|
send a packet. In most cases if we fail to send
|
|
after the retries we will kill the socket and
|
|
reconnect which may clear the network problem.
|
|
*/
|
|
if ((i >= 14) || (!server->noblocksnd && (i > 2))) {
|
|
cERROR(1,
|
|
("sends on sock %p stuck for 15 seconds",
|
|
ssocket));
|
|
rc = -EAGAIN;
|
|
break;
|
|
}
|
|
msleep(1 << i);
|
|
continue;
|
|
}
|
|
if (rc < 0)
|
|
break;
|
|
|
|
if (rc == total_len) {
|
|
total_len = 0;
|
|
break;
|
|
} else if (rc > total_len) {
|
|
cERROR(1, ("sent %d requested %d", rc, total_len));
|
|
break;
|
|
}
|
|
if (rc == 0) {
|
|
/* should never happen, letting socket clear before
|
|
retrying is our only obvious option here */
|
|
cERROR(1, ("tcp sent no data"));
|
|
msleep(500);
|
|
continue;
|
|
}
|
|
total_len -= rc;
|
|
/* the line below resets i */
|
|
for (i = first_vec; i < n_vec; i++) {
|
|
if (iov[i].iov_len) {
|
|
if (rc > iov[i].iov_len) {
|
|
rc -= iov[i].iov_len;
|
|
iov[i].iov_len = 0;
|
|
} else {
|
|
iov[i].iov_base += rc;
|
|
iov[i].iov_len -= rc;
|
|
first_vec = i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
i = 0; /* in case we get ENOSPC on the next send */
|
|
}
|
|
|
|
if ((total_len > 0) && (total_len != smb_buf_length + 4)) {
|
|
cFYI(1, ("partial send (%d remaining), terminating session",
|
|
total_len));
|
|
/* If we have only sent part of an SMB then the next SMB
|
|
could be taken as the remainder of this one. We need
|
|
to kill the socket so the server throws away the partial
|
|
SMB */
|
|
server->tcpStatus = CifsNeedReconnect;
|
|
}
|
|
|
|
if (rc < 0) {
|
|
cERROR(1, ("Error %d sending data on socket to server", rc));
|
|
} else
|
|
rc = 0;
|
|
|
|
/* Don't want to modify the buffer as a
|
|
side effect of this call. */
|
|
smb_buffer->smb_buf_length = smb_buf_length;
|
|
|
|
return rc;
|
|
}
|
|
|
|
int
|
|
smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
|
|
unsigned int smb_buf_length)
|
|
{
|
|
struct kvec iov;
|
|
|
|
iov.iov_base = smb_buffer;
|
|
iov.iov_len = smb_buf_length + 4;
|
|
|
|
return smb_sendv(server, &iov, 1);
|
|
}
|
|
|
|
static int wait_for_free_request(struct cifsSesInfo *ses, const int long_op)
|
|
{
|
|
if (long_op == CIFS_ASYNC_OP) {
|
|
/* oplock breaks must not be held up */
|
|
atomic_inc(&ses->server->inFlight);
|
|
return 0;
|
|
}
|
|
|
|
spin_lock(&GlobalMid_Lock);
|
|
while (1) {
|
|
if (atomic_read(&ses->server->inFlight) >=
|
|
cifs_max_pending){
|
|
spin_unlock(&GlobalMid_Lock);
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_inc(&ses->server->num_waiters);
|
|
#endif
|
|
wait_event(ses->server->request_q,
|
|
atomic_read(&ses->server->inFlight)
|
|
< cifs_max_pending);
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_dec(&ses->server->num_waiters);
|
|
#endif
|
|
spin_lock(&GlobalMid_Lock);
|
|
} else {
|
|
if (ses->server->tcpStatus == CifsExiting) {
|
|
spin_unlock(&GlobalMid_Lock);
|
|
return -ENOENT;
|
|
}
|
|
|
|
/* can not count locking commands against total
|
|
as they are allowed to block on server */
|
|
|
|
/* update # of requests on the wire to server */
|
|
if (long_op != CIFS_BLOCKING_OP)
|
|
atomic_inc(&ses->server->inFlight);
|
|
spin_unlock(&GlobalMid_Lock);
|
|
break;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int allocate_mid(struct cifsSesInfo *ses, struct smb_hdr *in_buf,
|
|
struct mid_q_entry **ppmidQ)
|
|
{
|
|
if (ses->server->tcpStatus == CifsExiting) {
|
|
return -ENOENT;
|
|
}
|
|
|
|
if (ses->server->tcpStatus == CifsNeedReconnect) {
|
|
cFYI(1, ("tcp session dead - return to caller to retry"));
|
|
return -EAGAIN;
|
|
}
|
|
|
|
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 */
|
|
}
|
|
*ppmidQ = AllocMidQEntry(in_buf, ses->server);
|
|
if (*ppmidQ == NULL)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
static int wait_for_response(struct cifsSesInfo *ses,
|
|
struct mid_q_entry *midQ,
|
|
unsigned long timeout,
|
|
unsigned long time_to_wait)
|
|
{
|
|
unsigned long curr_timeout;
|
|
|
|
for (;;) {
|
|
curr_timeout = timeout + jiffies;
|
|
wait_event_timeout(ses->server->response_q,
|
|
midQ->midState != MID_REQUEST_SUBMITTED, timeout);
|
|
|
|
if (time_after(jiffies, curr_timeout) &&
|
|
(midQ->midState == MID_REQUEST_SUBMITTED) &&
|
|
((ses->server->tcpStatus == CifsGood) ||
|
|
(ses->server->tcpStatus == CifsNew))) {
|
|
|
|
unsigned long lrt;
|
|
|
|
/* We timed out. Is the server still
|
|
sending replies ? */
|
|
spin_lock(&GlobalMid_Lock);
|
|
lrt = ses->server->lstrp;
|
|
spin_unlock(&GlobalMid_Lock);
|
|
|
|
/* Calculate time_to_wait past last receive time.
|
|
Although we prefer not to time out if the
|
|
server is still responding - we will time
|
|
out if the server takes more than 15 (or 45
|
|
or 180) seconds to respond to this request
|
|
and has not responded to any request from
|
|
other threads on the client within 10 seconds */
|
|
lrt += time_to_wait;
|
|
if (time_after(jiffies, lrt)) {
|
|
/* No replies for time_to_wait. */
|
|
cERROR(1, ("server not responding"));
|
|
return -1;
|
|
}
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
*
|
|
* Send an SMB Request. No response info (other than return code)
|
|
* needs to be parsed.
|
|
*
|
|
* flags indicate the type of request buffer and how long to wait
|
|
* and whether to log NT STATUS code (error) before mapping it to POSIX error
|
|
*
|
|
*/
|
|
int
|
|
SendReceiveNoRsp(const unsigned int xid, struct cifsSesInfo *ses,
|
|
struct smb_hdr *in_buf, int flags)
|
|
{
|
|
int rc;
|
|
struct kvec iov[1];
|
|
int resp_buf_type;
|
|
|
|
iov[0].iov_base = (char *)in_buf;
|
|
iov[0].iov_len = in_buf->smb_buf_length + 4;
|
|
flags |= CIFS_NO_RESP;
|
|
rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags);
|
|
cFYI(DBG2, ("SendRcvNoRsp flags %d rc %d", flags, rc));
|
|
|
|
return rc;
|
|
}
|
|
|
|
int
|
|
SendReceive2(const unsigned int xid, struct cifsSesInfo *ses,
|
|
struct kvec *iov, int n_vec, int *pRespBufType /* ret */,
|
|
const int flags)
|
|
{
|
|
int rc = 0;
|
|
int long_op;
|
|
unsigned int receive_len;
|
|
unsigned long timeout;
|
|
struct mid_q_entry *midQ;
|
|
struct smb_hdr *in_buf = iov[0].iov_base;
|
|
|
|
long_op = flags & CIFS_TIMEOUT_MASK;
|
|
|
|
*pRespBufType = CIFS_NO_BUFFER; /* no response buf yet */
|
|
|
|
if ((ses == NULL) || (ses->server == NULL)) {
|
|
cifs_small_buf_release(in_buf);
|
|
cERROR(1, ("Null session"));
|
|
return -EIO;
|
|
}
|
|
|
|
if (ses->server->tcpStatus == CifsExiting) {
|
|
cifs_small_buf_release(in_buf);
|
|
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 */
|
|
|
|
rc = wait_for_free_request(ses, long_op);
|
|
if (rc) {
|
|
cifs_small_buf_release(in_buf);
|
|
return rc;
|
|
}
|
|
|
|
/* 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 */
|
|
|
|
mutex_lock(&ses->server->srv_mutex);
|
|
|
|
rc = allocate_mid(ses, in_buf, &midQ);
|
|
if (rc) {
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
cifs_small_buf_release(in_buf);
|
|
/* Update # of requests on wire to server */
|
|
atomic_dec(&ses->server->inFlight);
|
|
wake_up(&ses->server->request_q);
|
|
return rc;
|
|
}
|
|
rc = cifs_sign_smb2(iov, n_vec, ses->server, &midQ->sequence_number);
|
|
if (rc) {
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
cifs_small_buf_release(in_buf);
|
|
goto out;
|
|
}
|
|
|
|
midQ->midState = MID_REQUEST_SUBMITTED;
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_inc(&ses->server->inSend);
|
|
#endif
|
|
rc = smb_sendv(ses->server, iov, n_vec);
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_dec(&ses->server->inSend);
|
|
midQ->when_sent = jiffies;
|
|
#endif
|
|
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
cifs_small_buf_release(in_buf);
|
|
|
|
if (rc < 0)
|
|
goto out;
|
|
|
|
if (long_op == CIFS_STD_OP)
|
|
timeout = 15 * HZ;
|
|
else if (long_op == CIFS_VLONG_OP) /* e.g. slow writes past EOF */
|
|
timeout = 180 * HZ;
|
|
else if (long_op == CIFS_LONG_OP)
|
|
timeout = 45 * HZ; /* should be greater than
|
|
servers oplock break timeout (about 43 seconds) */
|
|
else if (long_op == CIFS_ASYNC_OP)
|
|
goto out;
|
|
else if (long_op == CIFS_BLOCKING_OP)
|
|
timeout = 0x7FFFFFFF; /* large, but not so large as to wrap */
|
|
else {
|
|
cERROR(1, ("unknown timeout flag %d", long_op));
|
|
rc = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
/* 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 chance to complete */
|
|
timeout = 2 * HZ;
|
|
}
|
|
|
|
/* No user interrupts in wait - wreaks havoc with performance */
|
|
wait_for_response(ses, midQ, timeout, 10 * HZ);
|
|
|
|
spin_lock(&GlobalMid_Lock);
|
|
|
|
if (midQ->resp_buf == NULL) {
|
|
cERROR(1, ("No response to cmd %d mid %d",
|
|
midQ->command, midQ->mid));
|
|
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);
|
|
/* Update # of requests on wire to server */
|
|
atomic_dec(&ses->server->inFlight);
|
|
wake_up(&ses->server->request_q);
|
|
return rc;
|
|
}
|
|
|
|
spin_unlock(&GlobalMid_Lock);
|
|
receive_len = midQ->resp_buf->smb_buf_length;
|
|
|
|
if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) {
|
|
cERROR(1, ("Frame too large received. Length: %d Xid: %d",
|
|
receive_len, xid));
|
|
rc = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
/* rcvd frame is ok */
|
|
|
|
if (midQ->resp_buf &&
|
|
(midQ->midState == MID_RESPONSE_RECEIVED)) {
|
|
|
|
iov[0].iov_base = (char *)midQ->resp_buf;
|
|
if (midQ->largeBuf)
|
|
*pRespBufType = CIFS_LARGE_BUFFER;
|
|
else
|
|
*pRespBufType = CIFS_SMALL_BUFFER;
|
|
iov[0].iov_len = receive_len + 4;
|
|
|
|
dump_smb(midQ->resp_buf, 80);
|
|
/* 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(midQ->resp_buf,
|
|
&ses->server->mac_signing_key,
|
|
midQ->sequence_number+1);
|
|
if (rc) {
|
|
cERROR(1, ("Unexpected SMB signature"));
|
|
/* BB FIXME add code to kill session */
|
|
}
|
|
}
|
|
|
|
/* BB special case reconnect tid and uid here? */
|
|
rc = map_smb_to_linux_error(midQ->resp_buf,
|
|
flags & CIFS_LOG_ERROR);
|
|
|
|
/* convert ByteCount if necessary */
|
|
if (receive_len >= sizeof(struct smb_hdr) - 4
|
|
/* do not count RFC1001 header */ +
|
|
(2 * midQ->resp_buf->WordCount) + 2 /* bcc */ )
|
|
BCC(midQ->resp_buf) =
|
|
le16_to_cpu(BCC_LE(midQ->resp_buf));
|
|
if ((flags & CIFS_NO_RESP) == 0)
|
|
midQ->resp_buf = NULL; /* mark it so buf will
|
|
not be freed by
|
|
DeleteMidQEntry */
|
|
} else {
|
|
rc = -EIO;
|
|
cFYI(1, ("Bad MID state?"));
|
|
}
|
|
|
|
out:
|
|
DeleteMidQEntry(midQ);
|
|
atomic_dec(&ses->server->inFlight);
|
|
wake_up(&ses->server->request_q);
|
|
|
|
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;
|
|
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 (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
|
|
cERROR(1, ("Illegal length, greater than maximum frame, %d",
|
|
in_buf->smb_buf_length));
|
|
return -EIO;
|
|
}
|
|
|
|
rc = wait_for_free_request(ses, long_op);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* 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 */
|
|
|
|
mutex_lock(&ses->server->srv_mutex);
|
|
|
|
rc = allocate_mid(ses, in_buf, &midQ);
|
|
if (rc) {
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
/* Update # of requests on wire to server */
|
|
atomic_dec(&ses->server->inFlight);
|
|
wake_up(&ses->server->request_q);
|
|
return rc;
|
|
}
|
|
|
|
rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
|
|
if (rc) {
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
goto out;
|
|
}
|
|
|
|
midQ->midState = MID_REQUEST_SUBMITTED;
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_inc(&ses->server->inSend);
|
|
#endif
|
|
rc = smb_send(ses->server, in_buf, in_buf->smb_buf_length);
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_dec(&ses->server->inSend);
|
|
midQ->when_sent = jiffies;
|
|
#endif
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
|
|
if (rc < 0)
|
|
goto out;
|
|
|
|
if (long_op == CIFS_STD_OP)
|
|
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 */
|
|
else if (long_op == CIFS_ASYNC_OP)
|
|
goto out;
|
|
else if (long_op == CIFS_VLONG_OP) /* writes past EOF can be slow */
|
|
timeout = 180 * HZ;
|
|
else if (long_op == CIFS_LONG_OP)
|
|
timeout = 45 * HZ; /* should be greater than
|
|
servers oplock break timeout (about 43 seconds) */
|
|
else if (long_op == CIFS_BLOCKING_OP)
|
|
timeout = 0x7FFFFFFF; /* large but no so large as to wrap */
|
|
else {
|
|
cERROR(1, ("unknown timeout flag %d", long_op));
|
|
rc = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
if (signal_pending(current)) {
|
|
/* if signal pending do not hold up user for full smb timeout
|
|
but we still give response a chance to complete */
|
|
timeout = 2 * HZ;
|
|
}
|
|
|
|
/* No user interrupts in wait - wreaks havoc with performance */
|
|
wait_for_response(ses, midQ, timeout, 10 * HZ);
|
|
|
|
spin_lock(&GlobalMid_Lock);
|
|
if (midQ->resp_buf == NULL) {
|
|
cERROR(1, ("No response for cmd %d mid %d",
|
|
midQ->command, midQ->mid));
|
|
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);
|
|
/* Update # of requests on wire to server */
|
|
atomic_dec(&ses->server->inFlight);
|
|
wake_up(&ses->server->request_q);
|
|
return rc;
|
|
}
|
|
|
|
spin_unlock(&GlobalMid_Lock);
|
|
receive_len = midQ->resp_buf->smb_buf_length;
|
|
|
|
if (receive_len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) {
|
|
cERROR(1, ("Frame too large received. Length: %d Xid: %d",
|
|
receive_len, xid));
|
|
rc = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
/* 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, 0 /* no log */ );
|
|
|
|
/* 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_LE(out_buf));
|
|
} else {
|
|
rc = -EIO;
|
|
cERROR(1, ("Bad MID state?"));
|
|
}
|
|
|
|
out:
|
|
DeleteMidQEntry(midQ);
|
|
atomic_dec(&ses->server->inFlight);
|
|
wake_up(&ses->server->request_q);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/* Send an NT_CANCEL SMB to cause the POSIX blocking lock to return. */
|
|
|
|
static int
|
|
send_nt_cancel(struct cifsTconInfo *tcon, struct smb_hdr *in_buf,
|
|
struct mid_q_entry *midQ)
|
|
{
|
|
int rc = 0;
|
|
struct cifsSesInfo *ses = tcon->ses;
|
|
__u16 mid = in_buf->Mid;
|
|
|
|
header_assemble(in_buf, SMB_COM_NT_CANCEL, tcon, 0);
|
|
in_buf->Mid = mid;
|
|
mutex_lock(&ses->server->srv_mutex);
|
|
rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
|
|
if (rc) {
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
return rc;
|
|
}
|
|
rc = smb_send(ses->server, in_buf, in_buf->smb_buf_length);
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
return rc;
|
|
}
|
|
|
|
/* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
|
|
blocking lock to return. */
|
|
|
|
static int
|
|
send_lock_cancel(const unsigned int xid, struct cifsTconInfo *tcon,
|
|
struct smb_hdr *in_buf,
|
|
struct smb_hdr *out_buf)
|
|
{
|
|
int bytes_returned;
|
|
struct cifsSesInfo *ses = tcon->ses;
|
|
LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
|
|
|
|
/* We just modify the current in_buf to change
|
|
the type of lock from LOCKING_ANDX_SHARED_LOCK
|
|
or LOCKING_ANDX_EXCLUSIVE_LOCK to
|
|
LOCKING_ANDX_CANCEL_LOCK. */
|
|
|
|
pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
|
|
pSMB->Timeout = 0;
|
|
pSMB->hdr.Mid = GetNextMid(ses->server);
|
|
|
|
return SendReceive(xid, ses, in_buf, out_buf,
|
|
&bytes_returned, CIFS_STD_OP);
|
|
}
|
|
|
|
int
|
|
SendReceiveBlockingLock(const unsigned int xid, struct cifsTconInfo *tcon,
|
|
struct smb_hdr *in_buf, struct smb_hdr *out_buf,
|
|
int *pbytes_returned)
|
|
{
|
|
int rc = 0;
|
|
int rstart = 0;
|
|
unsigned int receive_len;
|
|
struct mid_q_entry *midQ;
|
|
struct cifsSesInfo *ses;
|
|
|
|
if (tcon == NULL || tcon->ses == NULL) {
|
|
cERROR(1, ("Null smb session"));
|
|
return -EIO;
|
|
}
|
|
ses = tcon->ses;
|
|
|
|
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 (in_buf->smb_buf_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
|
|
cERROR(1, ("Illegal length, greater than maximum frame, %d",
|
|
in_buf->smb_buf_length));
|
|
return -EIO;
|
|
}
|
|
|
|
rc = wait_for_free_request(ses, CIFS_BLOCKING_OP);
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* 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 */
|
|
|
|
mutex_lock(&ses->server->srv_mutex);
|
|
|
|
rc = allocate_mid(ses, in_buf, &midQ);
|
|
if (rc) {
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
return rc;
|
|
}
|
|
|
|
rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
|
|
if (rc) {
|
|
DeleteMidQEntry(midQ);
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
return rc;
|
|
}
|
|
|
|
midQ->midState = MID_REQUEST_SUBMITTED;
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_inc(&ses->server->inSend);
|
|
#endif
|
|
rc = smb_send(ses->server, in_buf, in_buf->smb_buf_length);
|
|
#ifdef CONFIG_CIFS_STATS2
|
|
atomic_dec(&ses->server->inSend);
|
|
midQ->when_sent = jiffies;
|
|
#endif
|
|
mutex_unlock(&ses->server->srv_mutex);
|
|
|
|
if (rc < 0) {
|
|
DeleteMidQEntry(midQ);
|
|
return rc;
|
|
}
|
|
|
|
/* Wait for a reply - allow signals to interrupt. */
|
|
rc = wait_event_interruptible(ses->server->response_q,
|
|
(!(midQ->midState == MID_REQUEST_SUBMITTED)) ||
|
|
((ses->server->tcpStatus != CifsGood) &&
|
|
(ses->server->tcpStatus != CifsNew)));
|
|
|
|
/* Were we interrupted by a signal ? */
|
|
if ((rc == -ERESTARTSYS) &&
|
|
(midQ->midState == MID_REQUEST_SUBMITTED) &&
|
|
((ses->server->tcpStatus == CifsGood) ||
|
|
(ses->server->tcpStatus == CifsNew))) {
|
|
|
|
if (in_buf->Command == SMB_COM_TRANSACTION2) {
|
|
/* POSIX lock. We send a NT_CANCEL SMB to cause the
|
|
blocking lock to return. */
|
|
|
|
rc = send_nt_cancel(tcon, in_buf, midQ);
|
|
if (rc) {
|
|
DeleteMidQEntry(midQ);
|
|
return rc;
|
|
}
|
|
} else {
|
|
/* Windows lock. We send a LOCKINGX_CANCEL_LOCK
|
|
to cause the blocking lock to return. */
|
|
|
|
rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
|
|
|
|
/* If we get -ENOLCK back the lock may have
|
|
already been removed. Don't exit in this case. */
|
|
if (rc && rc != -ENOLCK) {
|
|
DeleteMidQEntry(midQ);
|
|
return rc;
|
|
}
|
|
}
|
|
|
|
/* Wait 5 seconds for the response. */
|
|
if (wait_for_response(ses, midQ, 5 * HZ, 5 * HZ) == 0) {
|
|
/* We got the response - restart system call. */
|
|
rstart = 1;
|
|
}
|
|
}
|
|
|
|
spin_lock(&GlobalMid_Lock);
|
|
if (midQ->resp_buf) {
|
|
spin_unlock(&GlobalMid_Lock);
|
|
receive_len = midQ->resp_buf->smb_buf_length;
|
|
} else {
|
|
cERROR(1, ("No response for cmd %d mid %d",
|
|
midQ->command, midQ->mid));
|
|
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 > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE) {
|
|
cERROR(1, ("Frame too large received. Length: %d Xid: %d",
|
|
receive_len, xid));
|
|
rc = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
/* rcvd frame is ok */
|
|
|
|
if ((out_buf == NULL) || (midQ->midState != MID_RESPONSE_RECEIVED)) {
|
|
rc = -EIO;
|
|
cERROR(1, ("Bad MID state?"));
|
|
goto out;
|
|
}
|
|
|
|
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, 0 /* no log */ );
|
|
|
|
/* 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_LE(out_buf));
|
|
|
|
out:
|
|
DeleteMidQEntry(midQ);
|
|
if (rstart && rc == -EACCES)
|
|
return -ERESTARTSYS;
|
|
return rc;
|
|
}
|