nuttx/net/route/net_cacheroute.c
Gregory Nutt 97339e47f1 Check return from nxsem_wait_initialize()
Resolution of Issue 619 will require multiple steps, this part of the first step in that resolution:  Every call to nxsem_wait_uninterruptible() must handle the return value from nxsem_wait_uninterruptible properly.  This commit is only for those files under graphics/, mm/, net/, sched/, wireless/bluetooth.

Still to do:  Files under fs/, drivers/, and arch.  The last is 116 files and will take some effort.
2020-03-29 20:11:10 +01:00

813 lines
20 KiB
C

/****************************************************************************
* net/route/net_cacheroute.c
*
* 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/semaphore.h>
#include "route/cacheroute.h"
#include "route/route.h"
#if defined(CONFIG_ROUTE_IPv4_CACHEROUTE) || defined(CONFIG_ROUTE_IPv6_CACHEROUTE)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_ROUTE_MAX_IPv4_CACHEROUTES
# define CONFIG_ROUTE_MAX_IPv4_CACHEROUTES 4
#endif
#ifndef CONFIG_ROUTE_MAX_IPv6_CACHEROUTES
# define CONFIG_ROUTE_MAX_IPv6_CACHEROUTES 4
#endif
/* Routing table initializer */
#define cacheroute_init(rr) \
do \
{ \
(rr)->head = NULL; \
(rr)->tail = NULL; \
} \
while (0)
/****************************************************************************
* Private Types
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
/* This structure describes one entry in the routing table cache */
struct net_cache_ipv4_entry_s
{
struct net_route_ipv4_s entry;
FAR struct net_cache_ipv4_entry_s *flink;
};
/* This structure describes the head of a routing table cache list */
struct net_cache_ipv4_queue_s
{
FAR struct net_cache_ipv4_entry_s *head;
FAR struct net_cache_ipv4_entry_s *tail;
};
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
/* This structure describes one entry in the routing table cache */
struct net_cache_ipv6_entry_s
{
struct net_route_ipv6_s entry;
FAR struct net_cache_ipv6_entry_s *flink;
};
/* This structure describes the head of a routing table cache list */
struct net_cache_ipv6_queue_s
{
FAR struct net_cache_ipv6_entry_s *head;
FAR struct net_cache_ipv6_entry_s *tail;
};
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/* These are the routing tables */
#if defined(CONFIG_ROUTE_IPv4_CACHEROUTE)
/* The in-memory cache as a singly linked list. */
static struct net_cache_ipv4_queue_s g_ipv4_cache;
/* List of free routing table cache entries */
static struct net_cache_ipv4_queue_s g_free_ipv4cache;
/* Pre-allocated routing table cache entries */
static struct net_cache_ipv4_entry_s
g_prealloc_ipv4cache[CONFIG_ROUTE_MAX_IPv4_CACHEROUTES];
/* Serializes access to the routing table cache */
static sem_t g_ipv4_cachelock;
#endif
#if defined(CONFIG_ROUTE_IPv6_CACHEROUTE)
/* The in-memory routing tables are represented as singly linked lists. */
static struct net_cache_ipv6_queue_s g_ipv6_cache;
/* List of free routing table cache entries */
static struct net_cache_ipv6_queue_s g_free_ipv6cache;
/* Pre-allocated routing table cache entries */
static struct net_cache_ipv6_entry_s
g_prealloc_ipv6cache[CONFIG_ROUTE_MAX_IPv6_CACHEROUTES];
/* Serializes access to the routing table cache */
static sem_t g_ipv6_cachelock;
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: net_lock_ipv4_cache and net_lock_ipv6_cache
*
* Description:
* Lock the routing table cache list.
*
* Input Parameters:
* None
*
* Returned Value:
* Zero (OK) is returned on success; A negated errno value is returned on
* any failure.
*
****************************************************************************/
#define net_lock_ipv4_cache() nxsem_wait_uninterruptible(&g_ipv4_cachelock)
#define net_lock_ipv6_cache() nxsem_wait_uninterruptible(&g_ipv6_cachelock)
/****************************************************************************
* Name: net_unlock_ipv4_cache and net_unlock_ipv6_cache
*
* Description:
* Unlock the routing table cache list.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#define net_unlock_ipv4_cache() (void)nxsem_post(&g_ipv4_cachelock)
#define net_unlock_ipv6_cache() (void)nxsem_post(&g_ipv6_cachelock)
/****************************************************************************
* Name: net_add_newest_ipv4 and net_add_newest_ipv6
*
* Description:
* Add a new entry to the routing table cache list. The list is ordered
* by "new-ness" so this would be the entry at the head of the list.
*
* Input Parameters:
* cache - The cache entry to add to the head of the routing table cache
* list.
*
* Returned Value:
* None
*
* Assumptions:
* Caller has the routing table cache locked.
*
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
static void net_add_newest_ipv4(FAR struct net_cache_ipv4_entry_s *cache)
{
cache->flink = g_ipv4_cache.head;
if (!g_ipv4_cache.head)
{
g_ipv4_cache.tail = cache;
}
g_ipv4_cache.head = cache;
}
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
static void net_add_newest_ipv6(FAR struct net_cache_ipv6_entry_s *cache)
{
cache->flink = g_ipv6_cache.head;
if (!g_ipv6_cache.head)
{
g_ipv6_cache.tail = cache;
}
g_ipv6_cache.head = cache;
}
#endif
/****************************************************************************
* Name: net_remove_oldest_ipv4 and net_remove_oldest_ipv6
*
* Description:
* Remove the oldest entry from the routing table cache list. The list is
* ordered
*
* Input Parameters:
* None
*
* Returned Value:
* On success, a pointer to the oldest routing table cache entry is
* returned. NULL would be returned if the routing table cache is empty.
*
* Assumptions:
* Caller has the routing table cache locked.
*
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
FAR struct net_cache_ipv4_entry_s *net_remove_oldest_ipv4(void)
{
FAR struct net_cache_ipv4_entry_s *cache;
FAR struct net_cache_ipv4_entry_s *prev;
cache = g_ipv4_cache.tail;
if (cache != NULL)
{
if (g_ipv4_cache.head == g_ipv4_cache.tail)
{
g_ipv4_cache.head = NULL;
g_ipv4_cache.tail = NULL;
}
else
{
for (prev = g_ipv4_cache.head;
prev != NULL && prev->flink != cache;
prev = prev->flink);
if (prev != NULL)
{
prev->flink = NULL;
g_ipv4_cache.tail = prev;
}
}
cache->flink = NULL;
}
return cache;
}
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
FAR struct net_cache_ipv6_entry_s *net_remove_oldest_ipv6(void)
{
FAR struct net_cache_ipv6_entry_s *cache;
FAR struct net_cache_ipv6_entry_s *prev;
cache = g_ipv6_cache.tail;
if (cache != NULL)
{
if (g_ipv6_cache.head == g_ipv6_cache.tail)
{
g_ipv6_cache.head = NULL;
g_ipv6_cache.tail = NULL;
}
else
{
for (prev = g_ipv6_cache.head;
prev != NULL && prev->flink != cache;
prev = prev->flink);
if (prev != NULL)
{
prev->flink = NULL;
g_ipv6_cache.tail = prev;
}
}
cache->flink = NULL;
}
return cache;
}
#endif
/****************************************************************************
* Name: net_alloccache_ipv4 and net_alloccache_ipv6
*
* Description:
* Allocate one routing table cache entry by removing it from the free
* list. If the free list is empty, then remove the entry at the tail
* of the current routing table cache.
*
* Input Parameters:
* None
*
* Returned Value:
* On success, a pointer to the newly allocated routing table cache entry
* is returned. Should never fail
*
* Assumptions:
* Caller has the routing table cache locked.
*
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
FAR struct net_cache_ipv4_entry_s *net_alloccache_ipv4(void)
{
FAR struct net_cache_ipv4_entry_s *cache;
/* Remove the first entry from the free list */
cache = g_free_ipv4cache.head;
if (cache != NULL)
{
g_free_ipv4cache.head = cache->flink;
if (g_free_ipv4cache.head == NULL)
{
g_free_ipv4cache.tail = NULL;
}
cache->flink = NULL;
}
/* If the free list is empty, then remove the oldest entry at the tail of
* the routing table cache.
*/
else
{
/* If the free list is empty, then the cache list cannot be empty */
cache = net_remove_oldest_ipv4();
DEBUGASSERT(cache != NULL);
}
return cache;
}
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
FAR struct net_cache_ipv6_entry_s *net_alloccache_ipv6(void)
{
FAR struct net_cache_ipv6_entry_s *cache;
/* Remove the first entry from the free list */
cache = g_free_ipv6cache.head;
if (cache != NULL)
{
g_free_ipv6cache.head = cache->flink;
if (g_free_ipv6cache.head == NULL)
{
g_free_ipv6cache.tail = NULL;
}
cache->flink = NULL;
}
/* If the free list is empty, then remove the oldest entry at the tail of
* the routing table cache.
*/
else
{
/* If the free list is empty, then the cache list cannot be empty */
cache = net_remove_oldest_ipv6();
DEBUGASSERT(cache != NULL);
}
return cache;
}
#endif
/****************************************************************************
* Name: net_reset_ipv4_cache and net_reset_ipv6_cache
*
* Description:
* Clear the routing table cache and return the entries to the free list.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
static void net_reset_ipv4_cache(void)
{
int i;
cacheroute_init(&g_ipv4_cache);
cacheroute_init(&g_free_ipv4cache);
/* Add all of the pre-allocated routing table cache entries to a free list */
for (i = 0; i < CONFIG_ROUTE_MAX_IPv4_CACHEROUTES; i++)
{
net_add_newest_ipv4(&g_prealloc_ipv4cache[i]);
}
}
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
static void net_reset_ipv6_cache(void)
{
int i;
cacheroute_init(&g_ipv6_cache);
cacheroute_init(&g_free_ipv6cache);
/* Add all of the pre-allocated routing table entries to a free list */
for (i = 0; i < CONFIG_ROUTE_MAX_IPv6_CACHEROUTES; i++)
{
net_add_newest_ipv6(&g_prealloc_ipv6cache[i]);
}
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: net_init_cacheroute
*
* Description:
* Initialize the in-memory, routing table cache
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
* Assumptions:
* Called early in initialization so that no special protection is needed.
*
****************************************************************************/
void net_init_cacheroute(void)
{
/* Initialize the routing table cash and the free list */
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
nxsem_init(&g_ipv4_cachelock, 0, 1);
net_reset_ipv4_cache();
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
nxsem_init(&g_ipv6_cachelock, 0, 1);
net_reset_ipv6_cache();
#endif
}
/****************************************************************************
* Name: net_addcache_ipv4 and net_addcache_ipv6
*
* Description:
* Add one route to the routing table cache
*
* Input Parameters:
* None
*
* Returned Value:
* Zero (OK) is returned on success; a negated errno value is returned
* on any failure.
*
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
int net_addcache_ipv4(FAR struct net_route_ipv4_s *route)
{
FAR struct net_cache_ipv4_entry_s *cache;
FAR struct net_cache_ipv4_entry_s *prev;
int ret;
DEBUGASSERT(route != NULL);
/* Get exclusive access to the cache */
ret = net_lock_ipv4_cache();
if (ret < 0)
{
return ret;
}
/* First, check if the route already exists in the cache.
*
* Visit each entry in the cache
*/
for (prev = NULL, cache = g_ipv4_cache.head;
cache != NULL;
prev = cache, cache = cache->flink)
{
/* To match, the masked target addresses and netmasks must be the
* same.
*/
if (net_ipv4addr_cmp(route->target, cache->entry.target) &&
net_ipv4addr_cmp(route->netmask, cache->entry.netmask))
{
/* If the route already exists and is already at the head of the
* list, then do nothing. It is already the most recently used.
*/
if (prev == NULL)
{
net_unlock_ipv4_cache();
return OK;
}
/* Otherwise, remove the cache entry from the middle or end of
* the list.
*/
prev->flink = cache->flink;
if (g_ipv4_cache.tail == cache)
{
g_ipv4_cache.tail = prev;
}
cache->flink = NULL;
break;
}
}
/* If we did not find the entry in the list, then we will have to
* allocate a new entry.
*/
if (cache == NULL)
{
/* Allocate a new cache entry (should never fail) */
cache = net_alloccache_ipv4();
DEBUGASSERT(cache != NULL);
/* Copy the routing table entry into the allocated cache entry. */
memcpy(&cache->entry, route, sizeof(struct net_route_ipv4_s));
}
/* Then add the new cache entry as the newest entry in the table */
net_add_newest_ipv4(cache);
net_unlock_ipv4_cache();
return OK;
}
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
int net_addcache_ipv6(FAR struct net_route_ipv6_s *route)
{
FAR struct net_cache_ipv6_entry_s *cache;
FAR struct net_cache_ipv6_entry_s *prev;
int ret;
DEBUGASSERT(route != NULL);
/* Get exclusive access to the cache */
ret = net_lock_ipv6_cache();
if (ret < 0)
{
return ret;
}
/* First, check if the route already exists in the cache.
*
* Visit each entry in the cache.
*/
for (prev = NULL, cache = g_ipv6_cache.head;
cache != NULL;
prev = cache, cache = cache->flink)
{
/* To match, the masked target addresses and netmasks must be the
* same.
*/
if (net_ipv6addr_cmp(route->target, cache->entry.target) &&
net_ipv6addr_cmp(route->netmask, cache->entry.netmask))
{
/* If the route already exists and is already at the head of the
* list, then do nothing. It is already the most recently used.
*/
if (prev == NULL)
{
net_unlock_ipv6_cache();
return OK;
}
/* Otherwise, remove the cache entry from the middle or end of
* the list.
*/
prev->flink = cache->flink;
if (g_ipv6_cache.tail == cache)
{
g_ipv6_cache.tail = prev;
}
cache->flink = NULL;
break;
}
}
/* If we did not find the entry in the list, then we will have to
* allocate a new entry.
*/
if (cache == NULL)
{
/* Allocate a new cache entry (should never fail) */
cache = net_alloccache_ipv6();
DEBUGASSERT(cache != NULL);
/* Copy the routing table entry into the allocated cache entry */
memcpy(&cache->entry, route, sizeof(struct net_route_ipv6_s));
}
/* Then add the new cache entry as the newest entry in the table */
net_add_newest_ipv6(cache);
net_unlock_ipv6_cache();
return OK;
}
#endif
/****************************************************************************
* Name: net_foreachcache_ipv4/net_foreachcache_ipv6
*
* Description:
* Traverse the routing table cache
*
* Input Parameters:
* handler - Will be called for each route in the routing table cache.
* arg - An arbitrary value that will be passed tot he handler.
*
* Returned Value:
* Zero (OK) returned if the entire table was searched. A negated errno
* value will be returned in the event of a failure. Handlers may also
* terminate the search early with any non-zero value.
*
****************************************************************************/
#ifdef CONFIG_NET_IPv4
int net_foreachcache_ipv4(route_handler_ipv4_t handler, FAR void *arg)
{
FAR struct net_cache_ipv4_entry_s *cache;
FAR struct net_cache_ipv4_entry_s *next;
int ret = 0;
/* Get exclusive access to the cache */
ret = net_lock_ipv4_cache();
if (ret < 0)
{
return ret;
}
/* Visit each entry in the routing table */
for (cache = g_ipv4_cache.head; ret == 0 && cache != NULL; cache = next)
{
/* Get the next entry in the to visit. We do this BEFORE calling the
* handler because the handler may delete this entry.
*/
next = cache->flink;
ret = handler(&cache->entry, arg);
}
/* Unlock the cache */
net_unlock_ipv4_cache();
return ret;
}
#endif
#ifdef CONFIG_NET_IPv6
int net_foreachcache_ipv6(route_handler_ipv6_t handler, FAR void *arg)
{
FAR struct net_cache_ipv6_entry_s *cache;
FAR struct net_cache_ipv6_entry_s *next;
int ret = 0;
/* Get exclusive access to the cache */
ret = net_lock_ipv6_cache();
if (ret < 0)
{
return ret;
}
/* Visit each entry in the routing table */
for (cache = g_ipv6_cache.head; ret == 0 && cache != NULL; cache = next)
{
/* Get the next entry in the to visit. We do this BEFORE calling the
* handler because the handler may delete this entry.
*/
next = cache->flink;
ret = handler(&cache->entry, arg);
}
/* Unlock the cache */
net_unlock_ipv6_cache();
return ret;
}
#endif
/****************************************************************************
* Name: net_flushcache_ipv4 and net_flushcache_ipv6
*
* Description:
* Flush the content of the routing table cache
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_ROUTE_IPv4_CACHEROUTE
void net_flushcache_ipv4(void)
{
int ret;
/* Get exclusive access to the cache */
ret = net_lock_ipv4_cache();
if (ret >= 0)
{
/* Reset the cache */
net_reset_ipv4_cache();
/* Unlock the cache */
net_unlock_ipv4_cache();
}
}
#endif
#ifdef CONFIG_ROUTE_IPv6_CACHEROUTE
void net_flushcache_ipv6(void)
{
int ret;
/* Get exclusive access to the cache */
ret = net_lock_ipv6_cache();
if (ret >= 0)
{
/* Reset the cache */
net_reset_ipv6_cache();
/* Unlock the cache */
net_unlock_ipv6_cache();
}
}
#endif
#endif /* CONFIG_ROUTE_IPv4_CACHEROUTE || CONFIG_ROUTE_IPv6_CACHEROUTE */