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Major overhaul.

Browse Source 
List of functional changes:
   - Make a single device per single node with a single hook.
     This gives us parrallelizm, which can't be achieved on a single
     node with many devices/hooks. This also gives us flexibility - we
     can play with a particular device node, not affecting others.
   - Remove read queue as it is. Use struct ifqueue instead. This change
     removes a lot of extra memcpy()ing, m_devget()ting and m_copymem()ming.
     In ng_device_receivedata() we enqueue an mbuf and wake readers.
     In ngdread() we take one mbuf from qeueue and uiomove() it to
     userspace. If no mbuf is present we optionally block. [1]
   - In ngdwrite() we create an mbuf from uio using m_uiotombuf().
     This is faster then uiomove() into buffer, and then m_copydata(),
     and this is much better than huge m_pullup().
   - Perform locking of device
   - Perform locking of connection list.
   - Clear out _rcvmsg method, since it does nothing good yet.
   - Implement NGM_DEVICE_GET_DEVNAME message.
   - #if 0 ioctl method, while nothing is done here yet.
   - Return immediately from ngdwrite() if uio_resid == 0.

 List of tidyness changes:
   - Introduce device2priv(), to remove cut'n'paste.
   - Use MALLOC/FREE, instead of malloc/free.
   - Use unit2minor().
   - Use UID_ROOT/GID_WHEEL instead of 0/0.
   - Define NGD_DEVICE_DEVNAME, use it.
   - Use more nice macros for debugging. [2]
   - Return Exxx, not -1.

 style(9) changes:
   - No "#endif" after short block.
   - Break long lines.
   - Remove extra spaces, add needed spaces.

[1] Obtained from:      if_tun.c
[2] Obtained from:      ng_pppoe.c
Reviewed by:		marks
Approved by:		julian (mentor)
MFC after:		1 month
This commit is contained in:
Gleb Smirnoff 2004-10-18 20:13:57 +00:00
parent 8f30dde5fe
commit 547d34736b
3 changed files with 280 additions and 360 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sys/modules/netgraph/device/Makefile
View File

@ -2,6 +2,6 @@
KMOD= ng_device
SRCS= ng_device.c
SRCS+= device_if.h
SRCS+= device_if.h vnode_if.h
.include <bsd.kmod.mk>

603
sys/netgraph/ng_device.c
View File

@ -30,6 +30,12 @@
*
*/
#if 0
#define AAA printf("ng_device: %s\n", __func__ );
#else
#define AAA
#endif
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/ioccom.h>
@ -38,65 +44,63 @@
#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>
/* turn this on for verbose messages */
#define NGD_DEBUG
#define ERROUT(x) do { error = (x); goto done; } while (0)
/* Netgraph methods */
static ng_constructor_t ng_device_cons;
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_connect_t ng_device_connect;
static ng_rcvdata_t ng_device_rcvdata;
static ng_disconnect_t ng_device_disconnect;
static int ng_device_mod_event(module_t mod, int event, void *data);
static int ng_device_init(void);
static int get_free_unit(void);
/* Netgraph type */
static struct ng_type typestruct = {
static struct ng_type ngd_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_DEVICE_NODE_TYPE,
.mod_event = ng_device_mod_event,
.constructor = ng_device_cons,
.constructor = ng_device_constructor,
.rcvmsg = ng_device_rcvmsg,
.shutdown = ng_device_shutdown,
.newhook = ng_device_newhook,
.connect = ng_device_connect,
.rcvdata = ng_device_rcvdata,
.disconnect = ng_device_disconnect,
};
NETGRAPH_INIT(device, &typestruct);
/* per hook data */
struct ngd_connection {
SLIST_ENTRY(ngd_connection) links;
NETGRAPH_INIT(device, &ngd_typestruct);
/* per node data */
struct ngd_private {
struct ifqueue readq;
SLIST_ENTRY(ngd_private) links;
struct ng_node *node;
struct ng_hook *hook;
struct cdev *ngddev;
struct ng_hook *active_hook;
char *readq;
int loc;
struct mtx ngd_mtx;
int unit;
uint16_t flags;
#define NGDF_OPEN 0x0001
#define NGDF_RWAIT 0x0002
};
typedef struct ngd_private *priv_p;
/* global data */
struct ngd_softc {
SLIST_HEAD(, ngd_connection) head;
node_p node;
char nodename[NG_NODESIZ];
} ngd_softc;
/* the per connection receiving queue maximum */
#define NGD_QUEUE_SIZE (1024*10)
/* List of all active nodes and mutex to protect it */
static SLIST_HEAD(, ngd_private) ngd_nodes = SLIST_HEAD_INITIALIZER(ngd_nodes);
static struct mtx ng_device_mtx;
MTX_SYSINIT(ng_device, &ng_device_mtx, "ng_device", MTX_DEF);
/* Maximum number of NGD devices */
#define MAX_NGD 25 /* should be more than enough for now */
@ -105,316 +109,234 @@ 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_flags = D_NEEDGIANT,
.d_open = ngdopen,
.d_close = ngdclose,
.d_read = ngdread,
.d_write = ngdwrite,
#if 0
.d_ioctl = ngdioctl,
#endif
.d_poll = ngdpoll,
.d_name = "ngd",
.d_name = NG_DEVICE_DEVNAME,
};
/* Helper functions */
static int get_free_unit(void);
/******************************************************************************
* Netgraph methods
******************************************************************************/
/*
* this holds all the stuff that should be done at load time
* create new node
*/
static int
ng_device_mod_event(module_t mod, int event, void *data)
ng_device_constructor(node_p node)
{
int error = 0;
priv_p priv;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
AAA
switch (event) {
case MOD_LOAD:
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
ng_device_init();
break;
mtx_init(&priv->ngd_mtx, "ng_device", NULL, MTX_DEF);
mtx_lock(&priv->ngd_mtx);
case MOD_UNLOAD:
/* XXX do we need to do something specific ? */
/* ng_device_breakdown */
break;
mtx_lock(&ng_device_mtx);
default:
error = EOPNOTSUPP;
break;
priv->unit = get_free_unit();
if(priv->unit < 0) {
printf("%s: No free unit found by get_free_unit(), "
"increase MAX_NGD\n",__func__);
mtx_unlock(&ng_device_mtx);
mtx_destroy(&priv->ngd_mtx);
FREE(priv, M_NETGRAPH);
return(EINVAL);
}
return(error);
}
static int
ng_device_init()
{
struct ngd_softc *sc = &ngd_softc;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
SLIST_INIT(&sc->head);
if (ng_make_node_common(&typestruct, &sc->node) != 0) {
printf("%s(): ng_make_node_common failed\n",__func__);
return(ENXIO);
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_unlock(&ng_device_mtx);
mtx_destroy(&priv->ngd_mtx);
FREE(priv, M_NETGRAPH);
return(EINVAL);
}
sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE);
if (ng_name_node(sc->node, sc->nodename)) {
NG_NODE_UNREF(sc->node); /* make it go away again */
printf("%s(): ng_name_node failed\n",__func__);
return(ENXIO);
}
NG_NODE_SET_PRIVATE(sc->node, sc);
SLIST_INSERT_HEAD(&ngd_nodes, priv, links);
mtx_unlock(&ng_device_mtx);
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->si_drv1 = priv;
mtx_unlock(&priv->ngd_mtx);
return(0);
}
/*
* don't allow to be created, only the device can do that
* Process control message.
*/
static int
ng_device_cons(node_p node)
{
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
return(EINVAL);
}
/*
* Receive control message. We just bounce it back as a reply.
*/
static int
ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
struct ngd_softc *sc = &ngd_softc;
const priv_p priv = NG_NODE_PRIVATE(node);
struct ng_mesg *msg;
struct ng_mesg *resp = NULL;
int error = 0;
struct ngd_connection * connection = NULL;
struct ngd_connection *tmp = NULL;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
NGI_GET_MSG(item, msg);
SLIST_FOREACH(tmp,&sc->head,links) {
if(tmp->active_hook == lasthook) {
connection = tmp;
}
}
if(connection == NULL) {
printf("%s(): connection is still NULL, no hook found\n",__func__);
return(-1);
}
if (msg->header.typecookie == NGM_DEVICE_COOKIE) {
switch (msg->header.cmd) {
case NGM_DEVICE_GET_DEVNAME:
/* XXX: Fix when NGD_MAX us bigger */
NG_MKRESPONSE(resp, msg,
strlen(NG_DEVICE_DEVNAME) + 3, M_NOWAIT);
return(error);
}
if (resp == NULL)
ERROUT(ENOMEM);
static int
get_free_unit()
{
struct ngd_connection *tmp = NULL;
struct ngd_softc *sc = &ngd_softc;
int n = 0;
int unit = -1;
strlcpy((char *)resp->data, priv->ngddev->si_name,
strlen(priv->ngddev->si_name) + 1);
break;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
/* When there is no list yet, the first device unit is always 0. */
if SLIST_EMPTY(&sc->head) {
unit = 0;
return(unit);
}
/* Just do a brute force loop to find the first free unit that is
* smaller than MAX_NGD.
* Set MAX_NGD to a large value, doesn't impact performance.
*/
for(n = 0;n<MAX_NGD && unit == -1;n++) {
SLIST_FOREACH(tmp,&sc->head,links) {
if(tmp->unit == n) {
unit = -1;
default:
error = EINVAL;
break;
}
unit = n;
}
}
} else
error = EINVAL;
return(unit);
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* incoming hook
* Accept incoming hook. We support only one hook per node.
*/
static int
ng_device_newhook(node_p node, hook_p hook, const char *name)
{
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * new_connection = NULL;
priv_p priv = NG_NODE_PRIVATE(node);
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif
AAA
new_connection = malloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT);
if(new_connection == NULL) {
printf("%s(): ERROR: new_connection == NULL\n",__func__);
return(ENOMEM);
}
/* We have only one hook per node */
if (priv->hook != NULL)
return (EISCONN);
new_connection->unit = get_free_unit();
if(new_connection->unit<0) {
printf("%s: No free unit found by get_free_unit(), "
"increase MAX_NGD\n",__func__);
free(new_connection, M_DEVBUF);
return(EINVAL);
}
new_connection->ngddev = make_dev(&ngd_cdevsw, new_connection->unit, 0, 0,0600,"ngd%d",new_connection->unit);
if(new_connection->ngddev == NULL) {
printf("%s(): make_dev failed\n",__func__);
free(new_connection, M_DEVBUF);
return(EINVAL);
}
new_connection->readq = malloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO);
if(new_connection->readq == NULL) {
printf("%s(): readq malloc failed\n",__func__);
free(new_connection, M_DEVBUF);
return(ENOMEM);
}
/* point to begin of buffer */
new_connection->loc = 0;
new_connection->active_hook = hook;
SLIST_INSERT_HEAD(&sc->head, new_connection, links);
priv->hook = hook;
return(0);
}
/*
* we gave ok to a new hook
* now connect
*/
static int
ng_device_connect(hook_p hook)
{
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
return(0);
}
/*
* Receive data from hook
* 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;
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
char *buffer;
int error = 0;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif
AAA
NGI_GET_M(item, m);
NG_FREE_ITEM(item);
SLIST_FOREACH(tmp,&sc->head,links)
if(tmp->active_hook == hook)
connection = tmp;
if (connection == NULL) {
printf("%s(): connection is still NULL, no hook found\n",__func__);
ERROUT(ENOTCONN);
}
if ((m = m_pullup(m,m->m_len)) == NULL) {
printf("%s(): ERROR: m_pullup failed\n",__func__);
ERROUT(ENOMEM);
}
buffer = mtod(m,char *);
if ((connection->loc + m->m_len) < NGD_QUEUE_SIZE) {
memcpy(connection->readq + connection->loc, buffer, m->m_len);
connection->loc += m->m_len;
} else {
printf("%s(): queue full, first read out a bit\n",__func__);
ERROUT(ENOSPC);
}
done:
IF_LOCK(&priv->readq);
if (_IF_QFULL(&priv->readq)) {
_IF_DROP(&priv->readq);
IF_UNLOCK(&priv->readq);
NG_FREE_M(m);
return(error);
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 last link destroys the node
* Removal of the hook destroys the node.
*/
static int
ng_device_disconnect(hook_p hook)
{
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif
AAA
SLIST_FOREACH(tmp,&sc->head,links)
if(tmp->active_hook == hook)
connection = tmp;
destroy_dev(priv->ngddev);
mtx_destroy(&priv->ngd_mtx);
if(connection == NULL) {
printf("%s(): connection is still NULL, no hook found\n",__func__);
return(ENOTCONN);
}
mtx_lock(&ng_device_mtx);
SLIST_REMOVE(&ngd_nodes, priv, ngd_private, links);
mtx_unlock(&ng_device_mtx);
free(connection->readq, M_DEVBUF);
IF_DRAIN(&priv->readq);
mtx_destroy(&(priv)->readq.ifq_mtx);
destroy_dev(connection->ngddev);
FREE(priv, M_NETGRAPH);
SLIST_REMOVE(&sc->head,connection,ngd_connection,links);
free(connection, M_DEVBUF);
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;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
AAA
mtx_lock(&priv->ngd_mtx);
priv->flags |= NGDF_OPEN;
mtx_unlock(&priv->ngd_mtx);
return(0);
}
@ -425,15 +347,20 @@ ngdopen(struct cdev *dev, int flag, int mode, struct thread *td)
static int
ngdclose(struct cdev *dev, int flag, int mode, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif
AAA
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
*
@ -450,9 +377,7 @@ ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td
struct ng_mesg *msg;
struct ngd_param_s * datap;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
AAA
SLIST_FOREACH(tmp,&sc->head,links) {
if(tmp->ngddev == dev) {
@ -464,7 +389,6 @@ ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td
return(-1);
}
/* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */
NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
M_NOWAIT);
if (msg == NULL) {
@ -484,108 +408,76 @@ ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td
return(0);
}
#endif /* if 0 */
/*
* This function is called when a read(2) is done to our device.
* We pass the data available in kernelspace on into userland using
* uiomove.
* We process one mbuf from queue.
*/
static int
ngdread(struct cdev *dev, struct uio *uio, int flag)
{
int ret = 0, amnt;
char buffer[uio->uio_resid+1];
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
priv_p priv = (priv_p )dev->si_drv1;
struct mbuf *m;
int len, error = 0;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
AAA
SLIST_FOREACH(tmp,&sc->head,links) {
if(tmp->ngddev == dev) {
connection = tmp;
/* 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;
mtx_unlock(&priv->ngd_mtx);
if ((error = tsleep(priv, PCATCH | (PZERO + 1),
"ngdread", 0)) != 0)
return (error);
}
}
if(connection == NULL) {
printf("%s(): connection is still NULL, no dev found\n",__func__);
return(-1);
} 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);
}
while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) {
amnt = MIN(uio->uio_resid,connection->loc);
if (m)
m_freem(m);
memcpy(buffer,connection->readq, amnt);
memcpy(connection->readq, connection->readq+amnt,
connection->loc-amnt);
connection->loc -= amnt;
ret = uiomove((caddr_t)buffer, amnt, uio);
if(ret != 0)
goto error;
}
return(0);
error:
printf("%s(): uiomove returns error %d\n",__func__,ret);
/* do error cleanup here */
return(ret);
return (error);
}
/*
* This function is called when our device is written to.
* We read the data from userland into our local buffer and pass it on
* into the remote hook.
* 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)
{
int ret;
int error = 0;
priv_p priv = (priv_p )dev->si_drv1;
struct mbuf *m;
char buffer[uio->uio_resid];
int len = uio->uio_resid;
struct ngd_softc *sc =& ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
int error = 0;
#ifdef NGD_DEBUG
printf("%s()\n",__func__);
#endif /* NGD_DEBUG */
AAA
SLIST_FOREACH(tmp,&sc->head,links) {
if(tmp->ngddev == dev) {
connection = tmp;
}
}
if (uio->uio_resid == 0)
return (0);
if(connection == NULL) {
printf("%s(): connection is still NULL, no dev found\n",__func__);
return(-1);
}
if (uio->uio_resid < 0 || uio->uio_resid > IP_MAXPACKET)
return (EIO);
if (len > 0) {
if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0)
goto error;
} else
printf("%s(): len <= 0 : is this supposed to happen?!\n",__func__);
if ((m = m_uiotombuf(uio, M_DONTWAIT, 0)) == NULL)
return (ENOBUFS);
m = m_devget(buffer,len,0,NULL,NULL);
NG_SEND_DATA_ONLY(error, priv->hook, m);
NG_SEND_DATA_ONLY(error,connection->active_hook,m);
return(0);
error:
/* do error cleanup here */
printf("%s(): uiomove returned err: %d\n",__func__,ret);
return(ret);
return (error);
}
/*
@ -595,28 +487,49 @@ ngdwrite(struct cdev *dev, struct uio *uio, int flag)
static int
ngdpoll(struct cdev *dev, int events, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
int revents = 0;
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
if (events & (POLLIN | POLLRDNORM)) {
/* get the connection we have to know the loc from */
SLIST_FOREACH(tmp,&sc->head,links) {
if(tmp->ngddev == dev) {
connection = tmp;
}
}
if(connection == NULL) {
printf("%s(): ERROR: connection is still NULL,"
"no dev found\n",__func__);
return(-1);
}
if (connection->loc > 0)
if (events & (POLLIN | POLLRDNORM) &&
!IFQ_IS_EMPTY(&priv->readq))
revents |= events & (POLLIN | POLLRDNORM);
return (revents);
}
/******************************************************************************
* Helper subroutines
******************************************************************************/
static int
get_free_unit()
{
struct ngd_private *priv = NULL;
int n = 0;
int unit = -1;
AAA
mtx_assert(&ng_device_mtx, MA_OWNED);
/* When there is no list yet, the first device unit is always 0. */
if SLIST_EMPTY(&ngd_nodes)
return(0);
/* Just do a brute force loop to find the first free unit that is
* smaller than MAX_NGD.
* Set MAX_NGD to a large value, doesn't impact performance.
*/
for(n = 0; n<MAX_NGD && unit == -1; n++) {
SLIST_FOREACH(priv, &ngd_nodes, links) {
if(priv->unit == n) {
unit = -1;
break;
}
unit = n;
}
}
return(revents);
return (unit);
}

11
sys/netgraph/ng_device.h
View File

@ -31,12 +31,19 @@
/* Node type name and magic cookie */
#define NG_DEVICE_NODE_TYPE "device"
#define NGM_DEVICE_COOKIE 1009920473
#define NGM_DEVICE_COOKIE 1091129178
#define NG_DEVICE_DEVNAME "ngd"
/* Netgraph control messages */
enum {
NGM_DEVICE_GET_DEVNAME,
};
#if 0
/* passing ioctl params */
struct ngd_param_s {
void * p;
};
#endif
#endif /* _NETGRAPH_NG_DEVICE_H_ */