freebsd-dev/sys/netgraph/ng_device.c
Maksim Yevmenkin 75ae257016 Change m_uiotombuf so it will accept offset at which data should be copied
to the mbuf. Offset cannot exceed MHLEN bytes. This is currently used to
fix Ethernet header alignment problem on alpha and sparc64. Also change all
users of m_uiotombuf to pass proper offset.

Reviewed by:	jmg, sam
Tested by:	Sten Spans "sten AT blinkenlights DOT nl"
MFC after:	1 week
2005-05-04 18:55:03 +00:00

493 lines
11 KiB
C

/*-
* Copyright (c) 2002 Mark Santcroos <marks@ripe.net>
* Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org>
*
* 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 ``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 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.
*
* Netgraph "device" node
*
* This node presents a /dev/ngd%d device that interfaces to an other
* netgraph node.
*
* $FreeBSD$
*
*/
#if 0
#define DBG do { printf("ng_device: %s\n", __func__ ); } while (0)
#else
#define DBG do {} while (0)
#endif
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/ioccom.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/poll.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <net/if.h>
#include <net/if_var.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_device.h>
#define ERROUT(x) do { error = (x); goto done; } while (0)
/* Netgraph methods */
static int ng_device_mod_event(module_t, int, void *);
static ng_constructor_t ng_device_constructor;
static ng_rcvmsg_t ng_device_rcvmsg;
static ng_shutdown_t ng_device_shutdown;
static ng_newhook_t ng_device_newhook;
static ng_rcvdata_t ng_device_rcvdata;
static ng_disconnect_t ng_device_disconnect;
/* Netgraph type */
static struct ng_type ngd_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_DEVICE_NODE_TYPE,
.mod_event = ng_device_mod_event,
.constructor = ng_device_constructor,
.rcvmsg = ng_device_rcvmsg,
.shutdown = ng_device_shutdown,
.newhook = ng_device_newhook,
.rcvdata = ng_device_rcvdata,
.disconnect = ng_device_disconnect,
};
NETGRAPH_INIT(device, &ngd_typestruct);
/* per node data */
struct ngd_private {
struct ifqueue readq;
struct ng_node *node;
struct ng_hook *hook;
struct cdev *ngddev;
struct mtx ngd_mtx;
int unit;
uint16_t flags;
#define NGDF_OPEN 0x0001
#define NGDF_RWAIT 0x0002
};
typedef struct ngd_private *priv_p;
/* unit number allocator entity */
static struct unrhdr *ngd_unit;
/* Maximum number of NGD devices */
#define MAX_NGD 999
static d_close_t ngdclose;
static d_open_t ngdopen;
static d_read_t ngdread;
static d_write_t ngdwrite;
#if 0
static d_ioctl_t ngdioctl;
#endif
static d_poll_t ngdpoll;
static struct cdevsw ngd_cdevsw = {
.d_version = D_VERSION,
.d_open = ngdopen,
.d_close = ngdclose,
.d_read = ngdread,
.d_write = ngdwrite,
#if 0
.d_ioctl = ngdioctl,
#endif
.d_poll = ngdpoll,
.d_name = NG_DEVICE_DEVNAME,
};
/******************************************************************************
* Netgraph methods
******************************************************************************/
/*
* Handle loading and unloading for this node type.
*/
static int
ng_device_mod_event(module_t mod, int event, void *data)
{
int error = 0;
switch (event) {
case MOD_LOAD:
ngd_unit = new_unrhdr(0, MAX_NGD, NULL);
break;
case MOD_UNLOAD:
delete_unrhdr(ngd_unit);
break;
default:
error = EOPNOTSUPP;
break;
}
return (error);
}
/*
* create new node
*/
static int
ng_device_constructor(node_p node)
{
priv_p priv;
DBG;
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
/* Allocate unit number */
priv->unit = alloc_unr(ngd_unit);
/* Initialize mutexes and queue */
mtx_init(&priv->ngd_mtx, "ng_device", NULL, MTX_DEF);
mtx_init(&priv->readq.ifq_mtx, "ng_device queue", NULL, MTX_DEF);
IFQ_SET_MAXLEN(&priv->readq, ifqmaxlen);
/* Link everything together */
NG_NODE_SET_PRIVATE(node, priv);
priv->node = node;
priv->ngddev = make_dev(&ngd_cdevsw, unit2minor(priv->unit), UID_ROOT,
GID_WHEEL, 0600, NG_DEVICE_DEVNAME "%d", priv->unit);
if(priv->ngddev == NULL) {
printf("%s(): make_dev() failed\n",__func__);
mtx_destroy(&priv->ngd_mtx);
mtx_destroy(&priv->readq.ifq_mtx);
free_unr(ngd_unit, priv->unit);
FREE(priv, M_NETGRAPH);
return(EINVAL);
}
/* XXX: race here? */
priv->ngddev->si_drv1 = priv;
return(0);
}
/*
* Process control message.
*/
static int
ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = NG_NODE_PRIVATE(node);
struct ng_mesg *msg;
struct ng_mesg *resp = NULL;
int error = 0;
NGI_GET_MSG(item, msg);
if (msg->header.typecookie == NGM_DEVICE_COOKIE) {
switch (msg->header.cmd) {
case NGM_DEVICE_GET_DEVNAME:
/* XXX: Fix when MAX_NGD us bigger */
NG_MKRESPONSE(resp, msg,
strlen(NG_DEVICE_DEVNAME) + 4, M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
strlcpy((char *)resp->data, priv->ngddev->si_name,
strlen(priv->ngddev->si_name) + 1);
break;
default:
error = EINVAL;
break;
}
} else
error = EINVAL;
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Accept incoming hook. We support only one hook per node.
*/
static int
ng_device_newhook(node_p node, hook_p hook, const char *name)
{
priv_p priv = NG_NODE_PRIVATE(node);
DBG;
/* We have only one hook per node */
if (priv->hook != NULL)
return (EISCONN);
priv->hook = hook;
return(0);
}
/*
* Receive data from hook, write it to device.
*/
static int
ng_device_rcvdata(hook_p hook, item_p item)
{
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct mbuf *m;
DBG;
NGI_GET_M(item, m);
NG_FREE_ITEM(item);
IF_LOCK(&priv->readq);
if (_IF_QFULL(&priv->readq)) {
_IF_DROP(&priv->readq);
IF_UNLOCK(&priv->readq);
NG_FREE_M(m);
return (ENOBUFS);
}
_IF_ENQUEUE(&priv->readq, m);
IF_UNLOCK(&priv->readq);
mtx_lock(&priv->ngd_mtx);
if (priv->flags & NGDF_RWAIT) {
priv->flags &= ~NGDF_RWAIT;
wakeup(priv);
}
mtx_unlock(&priv->ngd_mtx);
return(0);
}
/*
* Removal of the hook destroys the node.
*/
static int
ng_device_disconnect(hook_p hook)
{
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
DBG;
destroy_dev(priv->ngddev);
mtx_destroy(&priv->ngd_mtx);
IF_DRAIN(&priv->readq);
mtx_destroy(&(priv)->readq.ifq_mtx);
free_unr(ngd_unit, priv->unit);
FREE(priv, M_NETGRAPH);
ng_rmnode_self(NG_HOOK_NODE(hook));
return(0);
}
/*
* Node shutdown. Everything is already done in disconnect method.
*/
static int
ng_device_shutdown(node_p node)
{
NG_NODE_UNREF(node);
return (0);
}
/******************************************************************************
* Device methods
******************************************************************************/
/*
* the device is opened
*/
static int
ngdopen(struct cdev *dev, int flag, int mode, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
DBG;
mtx_lock(&priv->ngd_mtx);
priv->flags |= NGDF_OPEN;
mtx_unlock(&priv->ngd_mtx);
return(0);
}
/*
* the device is closed
*/
static int
ngdclose(struct cdev *dev, int flag, int mode, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
DBG;
mtx_lock(&priv->ngd_mtx);
priv->flags &= ~NGDF_OPEN;
mtx_unlock(&priv->ngd_mtx);
return(0);
}
#if 0 /*
* The ioctl is transformed into netgraph control message.
* We do not process them, yet.
*/
/*
* process ioctl
*
* they are translated into netgraph messages and passed on
*
*/
static int
ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
{
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
int error = 0;
struct ng_mesg *msg;
struct ngd_param_s * datap;
DBG;
NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
M_NOWAIT);
if (msg == NULL) {
printf("%s(): msg == NULL\n",__func__);
goto nomsg;
}
/* pass the ioctl data into the ->data area */
datap = (struct ngd_param_s *)msg->data;
datap->p = addr;
NG_SEND_MSG_HOOK(error, sc->node, msg, connection->active_hook, 0);
if(error)
printf("%s(): NG_SEND_MSG_HOOK error: %d\n",__func__,error);
nomsg:
return(0);
}
#endif /* if 0 */
/*
* This function is called when a read(2) is done to our device.
* We process one mbuf from queue.
*/
static int
ngdread(struct cdev *dev, struct uio *uio, int flag)
{
priv_p priv = (priv_p )dev->si_drv1;
struct mbuf *m;
int len, error = 0;
DBG;
/* get an mbuf */
do {
IF_DEQUEUE(&priv->readq, m);
if (m == NULL) {
if (flag & IO_NDELAY)
return (EWOULDBLOCK);
mtx_lock(&priv->ngd_mtx);
priv->flags |= NGDF_RWAIT;
if ((error = msleep(priv, &priv->ngd_mtx,
PDROP | PCATCH | (PZERO + 1),
"ngdread", 0)) != 0)
return (error);
}
} while (m == NULL);
while (m && uio->uio_resid > 0 && error == 0) {
len = MIN(uio->uio_resid, m->m_len);
if (len != 0)
error = uiomove(mtod(m, void *), len, uio);
m = m_free(m);
}
if (m)
m_freem(m);
return (error);
}
/*
* This function is called when our device is written to.
* We read the data from userland into mbuf chain and pass it to the remote hook.
*
*/
static int
ngdwrite(struct cdev *dev, struct uio *uio, int flag)
{
priv_p priv = (priv_p )dev->si_drv1;
struct mbuf *m;
int error = 0;
DBG;
if (uio->uio_resid == 0)
return (0);
if (uio->uio_resid < 0 || uio->uio_resid > IP_MAXPACKET)
return (EIO);
if ((m = m_uiotombuf(uio, M_DONTWAIT, 0, 0)) == NULL)
return (ENOBUFS);
NG_SEND_DATA_ONLY(error, priv->hook, m);
return (error);
}
/*
* we are being polled/selected
* check if there is data available for read
*/
static int
ngdpoll(struct cdev *dev, int events, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
int revents = 0;
if (events & (POLLIN | POLLRDNORM) &&
!IFQ_IS_EMPTY(&priv->readq))
revents |= events & (POLLIN | POLLRDNORM);
return (revents);
}