incubator-nuttx/net/ipforward/ipfwd_alloc.c

161 lines
4.6 KiB
C

/****************************************************************************
* net/ipforward/ipfwd_alloc.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/net/tcp.h>
#include <nuttx/net/udp.h>
#include <nuttx/net/icmp.h>
#include <nuttx/net/icmpv6.h>
#include "ipforward/ipforward.h"
#ifdef CONFIG_NET_IPFORWARD
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef CONFIG_NET_IPv6
# define L2_MAXHDRLEN IPv6_HDRLEN
#else
# define L2_MAXHDRLEN IPv4_HDRLEN
#endif
#if defined(CONFIG_NET_TCP)
# define L3_MAXHDRLEN TCP_HDRLEN /* Could be up to TCP_MAX_HDRLEN */
#elif defined(CONFIG_NET_UDP)
# define L3_MAXHDRLEN UDP_HDRLEN
#elif defined(CONFIG_NET_ICMPv6)
# define L3_MAXHDRLEN ICMPv6_HDRLEN
#elif defined(CONFIG_NET_ICMP)
# define L3_MAXHDRLEN ICMP_HDRLEN
#endif
#define MAX_HDRLEN (L2_MAXHDRLEN + L3_MAXHDRLEN)
/****************************************************************************
* Private Data
****************************************************************************/
/* This is an array of pre-allocating forwarding structures */
static struct forward_s g_fwdpool[CONFIG_NET_IPFORWARD_NSTRUCT];
/* This is a list of free forwarding structures */
static FAR struct forward_s *g_fwdfree;
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ipfwd_initialize
*
* Description:
* Initialize the struct forward_s allocator.
*
* Assumptions:
* Called early in system initialization.
*
****************************************************************************/
void ipfwd_initialize(void)
{
FAR struct forward_s *fwd;
int i;
/* The IOB size must be such that the maximum L2 and L3 headers fit into
* the contiguous memory of the first IOB in the IOB chain.
*/
DEBUGASSERT(MAX_HDRLEN <= CONFIG_IOB_BUFSIZE);
/* Add all pre-allocated forwarding structures to the free list */
g_fwdfree = NULL;
for (i = 0; i < CONFIG_NET_IPFORWARD_NSTRUCT; i++)
{
fwd = &g_fwdpool[i];
fwd->f_flink = g_fwdfree;
g_fwdfree = fwd;
}
}
/****************************************************************************
* Name: ipfwd_alloc
*
* Description:
* Allocate a forwarding structure by removing a pre-allocated entry from
* a free list.
*
* Assumptions:
* Caller holds the network lock. Mutually excluvive access to the free
* list is assured by this lock.
*
****************************************************************************/
FAR struct forward_s *ipfwd_alloc(void)
{
FAR struct forward_s *fwd;
fwd = g_fwdfree;
if (fwd != NULL)
{
g_fwdfree = fwd->f_flink;
memset (fwd, 0, sizeof(struct forward_s));
}
return fwd;
}
/****************************************************************************
* Name: ipfwd_free
*
* Description:
* Free a forwarding structure by adding it to a free list.
*
* Assumptions:
* Caller holds the network lock. Mutually excluvive access to the free
* list is assured by this lock.
*
****************************************************************************/
void ipfwd_free(FAR struct forward_s *fwd)
{
fwd->f_flink = g_fwdfree;
g_fwdfree = fwd;
}
#endif /* CONFIG_NET_IPFORWARD */