freebsd-skq/sys/dev/iscsi/initiator/isc_soc.c
ru 3b1bf8c2e9 Replaced the misleading uses of a historical artefact M_TRYWAIT with M_WAIT.
Removed dead code that assumed that M_TRYWAIT can return NULL; it's not true
since the advent of MBUMA.

Reviewed by:	arch

There are ongoing disputes as to whether we want to switch to directly using
UMA flags M_WAITOK/M_NOWAIT for mbuf(9) allocation.
2008-03-25 09:39:02 +00:00

577 lines
15 KiB
C

/*-
* Copyright (c) 2005-2007 Daniel Braniss <danny@cs.huji.ac.il>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/*
| iSCSI
| $Id: isc_soc.c,v 1.26 2007/05/19 06:09:01 danny Exp danny $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_iscsi_initiator.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/ctype.h>
#include <sys/errno.h>
#include <sys/sysctl.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <sys/socketvar.h>
#include <sys/socket.h>
#include <sys/protosw.h>
#include <sys/proc.h>
#include <sys/ioccom.h>
#include <sys/queue.h>
#include <sys/kthread.h>
#include <sys/syslog.h>
#include <sys/mbuf.h>
#include <sys/user.h>
#include <dev/iscsi/initiator/iscsi.h>
#include <dev/iscsi/initiator/iscsivar.h>
#ifndef USE_MBUF
#define USE_MBUF
#endif
#ifdef USE_MBUF
/*
| a dummy function for freeing external storage for mbuf
*/
static void
nil_fn(void *a, void *b)
{
}
static int nil_refcnt = 0;
#endif /* USE_MBUF */
int
isc_sendPDU(isc_session_t *sp, pduq_t *pq)
{
pdu_t *pp = &pq->pdu;
int len, error;
#ifdef USE_MBUF
struct mbuf *mh, **mp;
#else
struct uio *uio = &pq->uio;
struct iovec *iv;
#endif /* USE_MBUF */
debug_called(8);
#ifndef USE_MBUF
bzero(uio, sizeof(struct uio));
uio->uio_rw = UIO_WRITE;
uio->uio_segflg = UIO_SYSSPACE;
uio->uio_td = sp->td;
uio->uio_iov = iv = pq->iov;
iv->iov_base = &pp->ipdu;
iv->iov_len = sizeof(union ipdu_u);
uio->uio_resid = pq->len;
iv++;
#else /* USE_MBUF */
/* mbuf for the iSCSI header */
MGETHDR(mh, M_WAIT, MT_DATA);
mh->m_len = mh->m_pkthdr.len = sizeof(union ipdu_u);
mh->m_pkthdr.rcvif = NULL;
MH_ALIGN(mh, sizeof(union ipdu_u));
bcopy(&pp->ipdu, mh->m_data, sizeof(union ipdu_u));
mh->m_next = NULL;
#endif /* USE_MBUF */
if(sp->hdrDigest)
pq->pdu.hdr_dig = sp->hdrDigest(&pp->ipdu, sizeof(union ipdu_u), 0);
if(pp->ahs_len) {
#ifndef USE_MBUF
iv->iov_base = pp->ahs;
iv->iov_len = pp->ahs_len;
iv++;
#else /* USE_MBUF */
/* Add any AHS to the iSCSI hdr mbuf */
/* XXX Assert: (mh->m_pkthdr.len + pp->ahs_len) < MHLEN */
bcopy(pp->ahs, (mh->m_data + mh->m_len), pp->ahs_len);
mh->m_len += pp->ahs_len;
mh->m_pkthdr.len += pp->ahs_len;
#endif /* USE_MBUF */
if(sp->hdrDigest)
pq->pdu.hdr_dig = sp->hdrDigest(&pp->ahs, pp->ahs_len, pq->pdu.hdr_dig);
}
if(sp->hdrDigest) {
debug(2, "hdr_dig=%x", pq->pdu.hdr_dig);
#ifndef USE_MBUF
iv->iov_base = &pp->hdr_dig;
iv->iov_len = sizeof(int);
iv++;
#else /* USE_MBUF */
/* Add header digest to the iSCSI hdr mbuf */
/* XXX Assert: (mh->m_pkthdr.len + 4) < MHLEN */
bcopy(&pp->hdr_dig, (mh->m_data + mh->m_len), sizeof(int));
mh->m_len += sizeof(int);
mh->m_pkthdr.len += sizeof(int);
#endif /* USE_MBUF */
}
#ifdef USE_MBUF
mp = &mh->m_next;
#endif /* USE_MBUF */
if(pq->pdu.ds) {
#ifndef USE_MBUF
iv->iov_base = pp->ds;
iv->iov_len = pp->ds_len;
while(iv->iov_len & 03) // the specs say it must be int alligned
iv->iov_len++;
iv++;
#else /* USE_MBUF */
struct mbuf *md;
int off = 0;
len = pp->ds_len;
while(len & 03) // the specs say it must be int alligned
len++;
while (len > 0) {
int l;
MGET(md, M_WAIT, MT_DATA);
md->m_ext.ref_cnt = &nil_refcnt;
l = min(MCLBYTES, len);
MEXTADD(md, pp->ds + off, l, nil_fn,
pp->ds + off, NULL, 0, EXT_EXTREF);
md->m_len = l;
md->m_next = NULL;
mh->m_pkthdr.len += l;
*mp = md;
mp = &md->m_next;
len -= l;
off += l;
}
#endif /* USE_MBUF */
}
if(sp->dataDigest) {
#ifdef USE_MBUF
struct mbuf *me;
#endif /* USE_MBUF */
pp->ds_dig = sp->dataDigest(pp->ds, pp->ds_len, 0);
#ifndef USE_MBUF
iv->iov_base = &pp->ds_dig;
iv->iov_len = sizeof(int);
iv++;
#else /* USE_MBUF */
MGET(me, M_WAIT, MT_DATA);
me->m_len = sizeof(int);
MH_ALIGN(mh, sizeof(int));
bcopy(&pp->ds_dig, me->m_data, sizeof(int));
me->m_next = NULL;
mh->m_pkthdr.len += sizeof(int);
*mp = me;
#endif /* USE_MBUF */
}
#ifndef USE_MBUF
uio->uio_iovcnt = iv - pq->iov;
sdebug(5, "opcode=%x iovcnt=%d uio_resid=%d itt=%x",
pp->ipdu.bhs.opcode, uio->uio_iovcnt, uio->uio_resid,
ntohl(pp->ipdu.bhs.itt));
sdebug(5, "sp=%p sp->soc=%p uio=%p sp->td=%p",
sp, sp->soc, uio, sp->td);
do {
len = uio->uio_resid;
error = sosend(sp->soc, NULL, uio, 0, 0, 0, sp->td);
if(uio->uio_resid == 0 || error || len == uio->uio_resid) {
if(uio->uio_resid) {
sdebug(2, "uio->uio_resid=%d uio->uio_iovcnt=%d error=%d len=%d",
uio->uio_resid, uio->uio_iovcnt, error, len);
if(error == 0)
error = EAGAIN; // 35
}
break;
}
/*
| XXX: untested code
*/
sdebug(1, "uio->uio_resid=%d uio->uio_iovcnt=%d",
uio->uio_resid, uio->uio_iovcnt);
iv = uio->uio_iov;
len -= uio->uio_resid;
while(uio->uio_iovcnt > 0) {
if(iv->iov_len > len) {
caddr_t bp = (caddr_t)iv->iov_base;
iv->iov_len -= len;
iv->iov_base = (void *)&bp[len];
break;
}
len -= iv->iov_len;
uio->uio_iovcnt--;
uio->uio_iov++;
iv++;
}
} while(uio->uio_resid);
if(error == 0) {
sp->stats.nsent++;
getbintime(&sp->stats.t_sent);
#else /* USE_MBUF */
if ((error = sosend(sp->soc, NULL, NULL, mh, 0, 0, sp->td)) != 0) {
m_freem(mh);
return (error);
#endif /* USE_MBUF */
}
#ifndef USE_MBUF
return error;
#else /* USE_MBUF */
sp->stats.nsent++;
getbintime(&sp->stats.t_sent);
return 0;
#endif /* USE_MBUF */
}
/*
| wait till a PDU header is received
| from the socket.
*/
/*
The format of the BHS is:
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|I| Opcode |F| Opcode-specific fields |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| LUN or Opcode-specific fields |
+ +
12| |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20/ Opcode-specific fields /
+/ /
+---------------+---------------+---------------+---------------+
48
*/
static __inline int
so_getbhs(isc_session_t *sp)
{
bhs_t *bhs = &sp->bhs;
struct uio *uio = &sp->uio;
struct iovec *iov = &sp->iov;
int error, flags;
debug_called(8);
iov->iov_base = bhs;
iov->iov_len = sizeof(bhs_t);
uio->uio_iov = iov;
uio->uio_iovcnt = 1;
uio->uio_rw = UIO_READ;
uio->uio_segflg = UIO_SYSSPACE;
uio->uio_td = curthread; // why ...
uio->uio_resid = sizeof(bhs_t);
flags = MSG_WAITALL;
error = soreceive(sp->soc, NULL, uio, 0, 0, &flags);
if(error)
debug(2, "error=%d so_error=%d uio->uio_resid=%d iov.iov_len=%zd",
error,
sp->soc->so_error, uio->uio_resid, iov->iov_len);
if(!error && (uio->uio_resid > 0)) {
debug(2, "error=%d so_error=%d uio->uio_resid=%d iov.iov_len=%zd so_state=%x",
error,
sp->soc->so_error, uio->uio_resid, iov->iov_len, sp->soc->so_state);
error = EAGAIN; // EPIPE;
}
return error;
}
/*
| so_recv gets called when there is at least
| an iSCSI header in the queue
*/
static int
so_recv(isc_session_t *sp, pduq_t *pq)
{
struct socket *so = sp->soc;
sn_t *sn = &sp->sn;
struct uio *uio = &pq->uio;
pdu_t *pp;
int error;
size_t n, len;
bhs_t *bhs;
u_int max, exp;
debug_called(8);
/*
| now calculate how much data should be in the buffer
| NOTE: digest is not verified/calculated - yet
*/
pp = &pq->pdu;
bhs = &pp->ipdu.bhs;
len = 0;
if(bhs->AHSLength) {
pp->ahs_len = bhs->AHSLength * 4;
len += pp->ahs_len;
}
if(sp->hdrDigest)
len += 4;
if(bhs->DSLength) {
n = bhs->DSLength;
#if BYTE_ORDER == LITTLE_ENDIAN
pp->ds_len = ((n & 0x00ff0000) >> 16)
| (n & 0x0000ff00)
| ((n & 0x000000ff) << 16);
#else
pp->ds_len = n;
#endif
len += pp->ds_len;
while(len & 03)
len++;
if(sp->dataDigest)
len += 4;
}
if((sp->opt.maxRecvDataSegmentLength > 0) && (len > sp->opt.maxRecvDataSegmentLength)) {
#if 0
xdebug("impossible PDU length(%d) opt.maxRecvDataSegmentLength=%d",
len, sp->opt.maxRecvDataSegmentLength);
// deep trouble here, probably all we can do is
// force a disconnect, XXX: check RFC ...
log(LOG_ERR,
"so_recv: impossible PDU length(%ld) from iSCSI %s/%s\n",
len, sp->opt.targetAddress, sp->opt.targetName);
#endif
/*
| XXX: this will realy screwup the stream.
| should clear up the buffer till a valid header
| is found, or just close connection ...
| should read the RFC.
*/
error = E2BIG;
goto out;
}
if(len) {
int flags;
uio->uio_resid = len;
uio->uio_td = curthread; // why ...
flags = MSG_WAITALL;
error = soreceive(so, NULL, uio, &pq->mp, NULL, &flags);
//if(error == EAGAIN)
// XXX: this needs work! it hangs iscontrol
if(error || uio->uio_resid)
goto out;
}
pq->len += len;
sdebug(6, "len=%d] opcode=0x%x ahs_len=0x%x ds_len=0x%x",
pq->len, bhs->opcode, pp->ahs_len, pp->ds_len);
max = ntohl(bhs->MaxCmdSN);
exp = ntohl(bhs->ExpStSN);
if(max < exp - 1 &&
max > exp - _MAXINCR) {
sdebug(2, "bad cmd window size");
error = EIO; // XXX: for now;
goto out; // error
}
if(SNA_GT(max, sn->maxCmd))
sn->maxCmd = max;
if(SNA_GT(exp, sn->expCmd))
sn->expCmd = exp;
sp->cws = sn->maxCmd - sn->expCmd + 1;
return 0;
out:
// XXX: need some work here
xdebug("have a problem, error=%d", error);
pdu_free(sp->isc, pq);
if(!error && uio->uio_resid > 0)
error = EPIPE;
return error;
}
/*
| wait for something to arrive.
| and if the pdu is without errors, process it.
*/
static int
so_input(isc_session_t *sp)
{
pduq_t *pq;
int error;
debug_called(8);
/*
| first read in the iSCSI header
*/
error = so_getbhs(sp);
if(error == 0) {
/*
| now read the rest.
*/
pq = pdu_alloc(sp->isc, 1); // OK to WAIT
pq->pdu.ipdu.bhs = sp->bhs;
pq->len = sizeof(bhs_t); // so far only the header was read
error = so_recv(sp, pq);
if(error != 0) {
error += 0x800; // XXX: just to see the error.
// terminal error
// XXX: close connection and exit
}
else {
sp->stats.nrecv++;
getbintime(&sp->stats.t_recv);
ism_recv(sp, pq);
}
}
return error;
}
/*
| one per active (connected) session.
| this thread is responsible for reading
| in packets from the target.
*/
static void
isc_soc(void *vp)
{
isc_session_t *sp = (isc_session_t *)vp;
struct socket *so = sp->soc;
int error;
debug_called(8);
sp->flags |= ISC_CON_RUNNING;
if(sp->cam_path)
ic_release(sp);
error = 0;
while(sp->flags & ISC_CON_RUN) {
// XXX: hunting ...
if(sp->soc == NULL || !(so->so_state & SS_ISCONNECTED)) {
debug(2, "sp->soc=%p", sp->soc);
break;
}
error = so_input(sp);
if(error == 0) {
#ifdef ISC_OWAITING
mtx_lock(&sp->io_mtx);
if(sp->flags & ISC_OWAITING) {
sp->flags &= ~ISC_OWAITING;
}
wakeup(&sp->flags);
mtx_unlock(&sp->io_mtx);
#else
wakeup(&sp->flags);
#endif
} else if(error == EPIPE)
break;
else if(error == EAGAIN) {
if(so->so_state & SS_ISCONNECTED)
// there seems to be a problem in 6.0 ...
tsleep(sp, PRIBIO, "isc_soc", 2*hz);
}
}
sdebug(2, "terminated, flags=%x so_count=%d so_state=%x error=%d",
sp->flags, so->so_count, so->so_state, error);
if((sp->proc != NULL) && sp->signal) {
PROC_LOCK(sp->proc);
psignal(sp->proc, sp->signal);
PROC_UNLOCK(sp->proc);
sp->flags |= ISC_SIGNALED;
sdebug(2, "pid=%d signaled(%d)", sp->proc->p_pid, sp->signal);
}
else {
// we have to do something ourselves
// like closing this session ...
}
/*
| we've been terminated
*/
// do we need this mutex ...?
mtx_lock(&sp->io_mtx);
sp->flags &= ~ISC_CON_RUNNING;
wakeup(&sp->soc);
mtx_unlock(&sp->io_mtx);
kproc_exit(0);
}
void
isc_stop_receiver(isc_session_t *sp)
{
int n = 5;
debug_called(8);
sdebug(4, "sp=%p sp->soc=%p", sp, sp? sp->soc: 0);
soshutdown(sp->soc, SHUT_RD);
mtx_lock(&sp->io_mtx);
sp->flags &= ~ISC_CON_RUN;
while(n-- && (sp->flags & ISC_CON_RUNNING)) {
sdebug(3, "waiting n=%d... flags=%x", n, sp->flags);
msleep(&sp->soc, &sp->io_mtx, PRIBIO, "isc_stpc", 5*hz);
}
mtx_unlock(&sp->io_mtx);
if(sp->fp != NULL)
fdrop(sp->fp, sp->td);
fputsock(sp->soc);
sp->soc = NULL;
sp->fp = NULL;
}
void
isc_start_receiver(isc_session_t *sp)
{
debug_called(8);
sp->flags |= ISC_CON_RUN;
kproc_create(isc_soc, sp, &sp->soc_proc, 0, 0, "iscsi%d", sp->sid);
}