psip.c

Minix比较全的源码

		psip_port->pp_rd_head= psip_fd;
	else
		psip_port->pp_rd_tail->pf_rd_next= psip_fd;
	psip_fd->pf_rd_next= NULL;
	psip_port->pp_rd_tail= psip_fd;

	psip_fd->pf_flags |= PFF_READ_IP;
	if (!(psip_fd->pf_flags & PFF_PROMISC))
		ipps_get(psip_port->pp_ipdev);
	if (psip_fd->pf_flags & PFF_READ_IP)
		return NW_SUSPEND;
	return NW_OK;
}

PRIVATE int psip_write(fd, count)
int fd;
size_t count;
{
	psip_port_t *psip_port;
	psip_fd_t *psip_fd;
	acc_t *pack, *hdr_pack;
	psip_io_hdr_t *hdr;
	size_t pack_len;
	ipaddr_t nexthop;

	assert(fd >= 0 && fd < PSIP_FD_NR);
	psip_fd= &psip_fd_table[fd];
	psip_port= psip_fd->pf_port;

	pack= (*psip_fd->pf_get_userdata)(psip_fd->pf_srfd, (size_t)0,
		count, FALSE);
	if (pack == NULL)
	{
		pack= (*psip_fd->pf_get_userdata)(psip_fd->pf_srfd, 
			(size_t)EFAULT, (size_t)0, FALSE);
		assert(pack == NULL);
		return NW_OK;
	}

	if (psip_fd->pf_flags & PFF_NEXTHOP)
	{
		pack_len= bf_bufsize(pack);
		if (pack_len <= sizeof(nexthop))
		{
			/* Something strange */
			bf_afree(pack); pack= NULL;
			pack= (*psip_fd->pf_get_userdata)(psip_fd->pf_srfd,
				(size_t)EPACKSIZE, (size_t)0, FALSE);
			assert(pack == NULL);
			return NW_OK;
		}
		pack= bf_packIffLess(pack, sizeof(nexthop));
		nexthop= *(ipaddr_t *)ptr2acc_data(pack);
		pack= bf_delhead(pack, sizeof(nexthop));

		/* Map multicast to broadcast */
		if ((nexthop & HTONL(0xE0000000)) == HTONL(0xE0000000))
			nexthop= HTONL(0xffffffff);
	}
	else
	{
		/* Assume point to point */
		nexthop= HTONL(0x00000000);
	}

	if (psip_port->pp_flags & PPF_PROMISC)
	{
		/* Deal with promiscuous mode. */
		hdr_pack= bf_memreq(sizeof(*hdr));
		hdr= (psip_io_hdr_t *)ptr2acc_data(hdr_pack);
		memset(hdr, '\0', sizeof(*hdr));
		hdr->pih_flags |= PF_REM2LOC;
		hdr->pih_nexthop= nexthop;

		pack->acc_linkC++;
		hdr_pack->acc_next= pack;
		hdr_pack->acc_ext_link= NULL;
		if (psip_port->pp_promisc_head)
		{
			/* Append at the end. */
			psip_port->pp_promisc_tail->acc_ext_link= hdr_pack;
			psip_port->pp_promisc_tail= hdr_pack;
		}
		else
		{
			/* First packet. */
			psip_port->pp_promisc_head= hdr_pack;
			psip_port->pp_promisc_tail= hdr_pack;
			if (psip_port->pp_rd_head)
				promisc_restart_read(psip_port);
		}
	}
	ipps_put(psip_port->pp_ipdev, nexthop, pack);
	pack= (*psip_fd->pf_get_userdata)(psip_fd->pf_srfd, (size_t)count,
		(size_t)0, FALSE);
	assert(pack == NULL);
	return NW_OK;
}

PRIVATE int psip_select(fd, operations)
int fd;
unsigned operations;
{
	printf("psip_select: not implemented\n");
	return 0;
}

PRIVATE void psip_close(fd)
int fd;
{
	psip_port_t *psip_port;
	psip_fd_t *psip_fd;

	assert(fd >= 0 && fd < PSIP_FD_NR);
	psip_fd= &psip_fd_table[fd];
	psip_port= psip_fd->pf_port;

	if (psip_fd->pf_flags & PFF_PROMISC)
	{
		/* Check if the port should still be in promiscuous mode.
		 */
		psip_fd->pf_flags &= ~PFF_PROMISC;
		check_promisc(psip_fd->pf_port);
	}

	assert(psip_port->pp_opencnt >0);
	psip_port->pp_opencnt--;
	psip_fd->pf_flags= PFF_EMPTY;
	ipps_get(psip_port->pp_ipdev);

}

PRIVATE int psip_cancel(fd, which_operation)
int fd;
int which_operation;
{
	psip_port_t *psip_port;
	psip_fd_t *psip_fd, *prev_fd, *tmp_fd;
	int result;

	DBLOCK(1, printf("psip_cancel(%d, %d)\n", fd, which_operation));

	assert(fd >= 0 && fd < PSIP_FD_NR);
	psip_fd= &psip_fd_table[fd];
	psip_port= psip_fd->pf_port;

	switch(which_operation)
	{
	case SR_CANCEL_IOCTL:
		ip_panic(( "should not be here" ));
	case SR_CANCEL_READ:
		assert(psip_fd->pf_flags & PFF_READ_IP);
		for (prev_fd= NULL, tmp_fd= psip_port->pp_rd_head; tmp_fd;
			prev_fd= tmp_fd, tmp_fd= tmp_fd->pf_rd_next)
		{
			if (tmp_fd == psip_fd)
				break;
		}
		if (tmp_fd == NULL)
			ip_panic(( "unable to find to request to cancel" ));
		if (prev_fd == NULL)
			psip_port->pp_rd_head= psip_fd->pf_rd_next;
		else
			prev_fd->pf_rd_next= psip_fd->pf_rd_next;
		if (psip_fd->pf_rd_next == NULL)
			psip_port->pp_rd_tail= prev_fd;
		psip_fd->pf_flags &= ~PFF_READ_IP;
		result= (*psip_fd->pf_put_userdata)(psip_fd->pf_srfd,
						(size_t)EINTR, NULL, FALSE);
		assert(result == NW_OK);
		break;
	case SR_CANCEL_WRITE:
		ip_panic(( "should not be here" ));
	default:
		ip_panic(( "invalid operation for cancel" ));
	}
	return NW_OK;
}

PRIVATE void promisc_restart_read(psip_port)
psip_port_t *psip_port;
{
	psip_fd_t *psip_fd, *prev, *next;
	acc_t *pack;
	size_t buf_size;
	int result, result1;

	/* Overkill at the moment: just one reader in promiscious mode is
	 * allowed.
	 */
	pack= psip_port->pp_promisc_head;
	if (!pack)
		return;
	assert(pack->acc_ext_link == NULL);

	for(psip_fd= psip_port->pp_rd_head, prev= NULL; psip_fd;
		prev= psip_fd, psip_fd= psip_fd->pf_rd_next)
	{
again:
		if (!(psip_fd->pf_flags & PFF_PROMISC))
			continue;
		next= psip_fd->pf_rd_next;
		if (prev)
			prev->pf_rd_next= next;
		else
			psip_port->pp_rd_head= next;
		if (!next)
			psip_port->pp_rd_tail= prev;

		assert(psip_fd->pf_flags & PFF_READ_IP);
		psip_fd->pf_flags &= ~PFF_READ_IP;

		buf_size= bf_bufsize(pack);
		if (buf_size <= psip_fd->pf_rd_count)
		{
			psip_port->pp_promisc_head= pack->acc_ext_link;
			result= (*psip_fd->pf_put_userdata)(psip_fd->pf_srfd, 
				(size_t)0, pack, FALSE);
			if (result == NW_OK)
				result= buf_size;
		}
		else
			result= EPACKSIZE;

		result1= (*psip_fd->pf_put_userdata)(psip_fd->pf_srfd,
				(size_t)result, NULL, FALSE);
		assert(result1 == NW_OK);

		if (psip_port->pp_promisc_head)
		{
			/* Restart from the beginning */
			assert(result == EPACKSIZE);
			psip_fd= psip_port->pp_rd_head;
			prev= NULL;
			goto again;
		}
		break;
	}
}

PRIVATE int psip_setopt(psip_fd, newoptp)
psip_fd_t *psip_fd;
nwio_psipopt_t *newoptp;
{
	nwio_psipopt_t oldopt;
	unsigned int new_en_flags, new_di_flags, old_en_flags, old_di_flags;
	unsigned long new_flags;

	oldopt= psip_fd->pf_psipopt;

	old_en_flags= oldopt.nwpo_flags & 0xffff;
	old_di_flags= (oldopt.nwpo_flags >> 16) & 0xffff;

	new_en_flags= newoptp->nwpo_flags & 0xffff;
	new_di_flags= (newoptp->nwpo_flags >> 16) & 0xffff;

	if (new_en_flags & new_di_flags)
		return EBADMODE;

	/* NWUO_LOCADDR_MASK */
	if (!((new_en_flags | new_di_flags) & NWPO_PROMISC_MASK))
	{
		new_en_flags |= (old_en_flags & NWPO_PROMISC_MASK);
		new_di_flags |= (old_di_flags & NWPO_PROMISC_MASK);
	}

	new_flags= ((unsigned long)new_di_flags << 16) | new_en_flags;
	if ((new_flags & NWPO_EN_PROMISC) &&
		(psip_fd->pf_port->pp_flags & PPF_PROMISC))
	{
		printf("psip_setopt: EBUSY for port %d, flags 0x%x\n",
			psip_fd->pf_port - psip_port_table,
			psip_fd->pf_port->pp_flags);
		/* We can support only one at a time. */
		return EBUSY;
	}

	psip_fd->pf_psipopt= *newoptp;
	psip_fd->pf_psipopt.nwpo_flags= new_flags;

	return NW_OK;
}

PRIVATE void check_promisc(psip_port)
psip_port_t *psip_port;
{
	int i;
	psip_fd_t *psip_fd;
	acc_t *acc, *acc_next;

	/* Check if the port should still be in promiscuous mode.  Overkill
	 * at the moment.
	 */
	if (!(psip_port->pp_flags & PPF_PROMISC))
		return;

	psip_port->pp_flags &= ~PPF_PROMISC;
	for (i= 0, psip_fd= psip_fd_table; i<PSIP_FD_NR; i++, psip_fd++)
	{
		if ((psip_fd->pf_flags & (PFF_INUSE|PFF_PROMISC)) !=
			(PFF_INUSE|PFF_PROMISC))
		{
			continue;
		}
		if (psip_fd->pf_port != psip_port)
			continue;
		printf("check_promisc: setting PROMISC for port %d\n",
			psip_port-psip_port_table);
		psip_port->pp_flags |= PPF_PROMISC;
		break;
	}
	if (!(psip_port->pp_flags & PPF_PROMISC))
	{
		/* Delete queued packets. */
		acc= psip_port->pp_promisc_head;
		psip_port->pp_promisc_head= NULL;
		while (acc)
		{
			acc_next= acc->acc_ext_link;
			bf_afree(acc);
			acc= acc_next;
		}
	}
}

PRIVATE void psip_buffree (priority)
int priority;
{
	int i;
	psip_port_t *psip_port;
	acc_t *tmp_acc, *next_acc;

	if (priority == PSIP_PRI_EXP_PROMISC)
	{
		for (i=0, psip_port= psip_port_table; i<psip_conf_nr;
			i++, psip_port++)
		{
			if (!(psip_port->pp_flags & PPF_CONFIGURED) )
				continue;
			if (psip_port->pp_promisc_head)
			{
				tmp_acc= psip_port->pp_promisc_head;
				while(tmp_acc)
				{
					next_acc= tmp_acc->acc_ext_link;
					bf_afree(tmp_acc);
					tmp_acc= next_acc;
				}
				psip_port->pp_promisc_head= NULL;
			}
		}
	}
}

#ifdef BUF_CONSISTENCY_CHECK
PRIVATE void psip_bufcheck()
{
	int i;
	psip_port_t *psip_port;
	acc_t *tmp_acc;

	for (i= 0, psip_port= psip_port_table; i<psip_conf_nr;
		i++, psip_port++)
	{
		for (tmp_acc= psip_port->pp_promisc_head; tmp_acc; 
			tmp_acc= tmp_acc->acc_ext_link)
		{
			bf_check_acc(tmp_acc);
		}
	}
}
#endif

/*
reply_thr_put
*/

PRIVATE void reply_thr_put(psip_fd, reply, for_ioctl)
psip_fd_t *psip_fd;
int reply;
int for_ioctl;
{
	int result;

	result= (*psip_fd->pf_put_userdata)(psip_fd->pf_srfd, reply,
		(acc_t *)0, for_ioctl);
	assert(result == NW_OK);
}

/*
reply_thr_get
*/

PRIVATE void reply_thr_get(psip_fd, reply, for_ioctl)
psip_fd_t *psip_fd;
int reply;
int for_ioctl;
{
	acc_t *result;
	result= (*psip_fd->pf_get_userdata)(psip_fd->pf_srfd, reply,
		(size_t)0, for_ioctl);
	assert (!result);
}


/*
 * $PchId: psip.c,v 1.15 2005/06/28 14:19:29 philip Exp $
 */