/****************************************************************************
* net/uip/uip_igmpgroup.c
* IGMP group data structure management logic
*
* Copyright (C) 2010 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* The NuttX implementation of IGMP was inspired by the IGMP add-on for the
* lwIP TCP/IP stack by Steve Reynolds:
*
* Copyright (c) 2002 CITEL Technologies Ltd.
* All rights reserved.
*
* 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.
* 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``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 CITEL TECHNOLOGIES OR CONTRIBUTORS 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdlib.h>
#include <string.h>
#include <queue.h>
#include <debug.h>
#include <arch/irq.h>
#include <nuttx/arch.h>
#include <nuttx/kmalloc.h>
#include <net/uip/uip.h>
#include <net/uip/uip-igmp.h>
#include "uip_internal.h"
#ifdef CONFIG_NET_IGMP
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef CONFIG_NET_IPv6
# error "IGMP for IPv6 not supported"
#endif
#ifndef CONFIG_PREALLOC_IGMPGROUPS
# define CONFIG_PREALLOC_IGMPGROUPS 4
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/* malloc() cannot be called from an interrupt handler. To work around this,
* a small number of IGMP groups are preallocated just for use in interrupt
* handling logic.
*/
static struct igmp_group_s g_preallocgrps[CONFIG_PREALLOC_IGMPGROUPS];
static FAR sq_queue_t g_freelist;
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: uip_grpalloc
*
* Description:
* Allocate a new group from heap memory.
*
* Assumptions:
* Calls malloc and so cannot be called from an interrupt handler.
*
****************************************************************************/
static inline FAR struct igmp_group_s *uip_grpheapalloc(void)
{
return (FAR struct igmp_group_s *)zalloc(sizeof(struct igmp_group_s));
}
/****************************************************************************
* Name: uip_grpprealloc
*
* Description:
* Allocate a new group from the pre-allocated groups.
*
* Assumptions:
* This function should only be called from an interrupt handler (or with
* interrupts disabled).
*
****************************************************************************/
static inline FAR struct igmp_group_s *uip_grpprealloc(void)
{
FAR struct igmp_group_s *group = (FAR struct igmp_group_s *)sq_remfirst(&g_freelist);
if (group)
{
memset(group, 0, sizeof(struct igmp_group_s));
group->flags = IGMP_PREALLOCATED;
}
return group;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: uip_grpinit
*
* Description:
* One-time initialization of group data.
*
* Assumptions:
* Called only during early boot phases (pre-multitasking).
*
****************************************************************************/
void uip_grpinit(void)
{
FAR struct igmp_group_s *group;
int i;
for (i = 0; i < CONFIG_PREALLOC_IGMPGROUPS; i++)
{
group = &g_preallocgrps[i];
sq_addfirst((FAR sq_entry_t *)group, &g_freelist);
}
}
/****************************************************************************
* Name: uip_grpalloc
*
* Description:
* Allocate a new group from heap memory.
*
* Assumptions:
* May be called from either user or interrupt level processing.
*
****************************************************************************/
FAR struct igmp_group_s *uip_grpalloc(FAR struct uip_driver_s *dev, FAR uip_ipaddr_t *addr)
{
FAR struct igmp_group_s *group;
irqstate_t flags;
nllvdbg("addr: %08x dev: %p\n", *addr, dev);
if (up_interrupt_context())
{
group = uip_grpheapalloc();
}
else
{
group = uip_grpprealloc();
}
/* Check if we succesfully allocated a group structure */
if (group)
{
/* Initialize the non-zero elements of the group structure */
uip_ipaddr_copy(group->grpaddr, addr);
sem_init(&group->sem, 0, 0);
/* Interrupts must be disabled in order to modify the group list */
flags = irqsave();
/* Add the group structure to the list in the device structure */
sq_addfirst((FAR sq_entry_t*)group, &dev->grplist);
irqrestore(flags);
}
return group;
}
/****************************************************************************
* Name: uip_grpfind
*
* Description:
* Find an existing group.
*
* Assumptions:
* May be called from either user or interrupt level processing.
*
****************************************************************************/
FAR struct igmp_group_s *uip_grpfind(FAR struct uip_driver_s *dev, FAR uip_ipaddr_t *addr)
{
FAR struct igmp_group_s *group;
irqstate_t flags;
/* We must disable interrupts because we don't which context we were called
* from.
*/
flags = irqsave();
for (group = (FAR struct igmp_group_s *)dev->grplist.head; group; group = group->next)
{
if (uip_ipaddr_cmp(&group->grpaddr, addr))
{
break;
}
}
irqrestore(flags);
return group;
}
/****************************************************************************
* Name: uip_grpallocfind
*
* Description:
* Find an existing group. If not found, create a new group for the
* address.
*
* Assumptions:
* May be called from either user or interrupt level processing.
*
****************************************************************************/
FAR struct igmp_group_s *uip_grpallocfind(FAR struct uip_driver_s *dev, FAR uip_ipaddr_t *addr)
{
FAR struct igmp_group_s *group = uip_grpfind(dev, addr);
if (!group)
{
group = uip_grpalloc(dev, addr);
}
return group;
}
/****************************************************************************
* Name: uip_grpfree
*
* Description:
* Release a previously allocated group.
*
* Assumptions:
* May be called from either user or interrupt level processing.
*
****************************************************************************/
void uip_grpfree(FAR struct uip_driver_s *dev, FAR struct igmp_group_s *group)
{
/* First, remove the group structure from the group list in the device
* structure
*/
irqstate_t flags = irqsave();
DEBUGASSERT(sq_rem((FAR sq_entry_t*)group, &dev->grplist) != NULL);
/* Destroy the wait semapore */
(void)sem_destroy(&group->sem);
/* Then release the group structure resources. Check first if this is one
* of the pre-allocated group structures that we will retain in a free list.
*/
if (IS_PREALLOCATED(group->flags))
{
sq_addlast((FAR sq_entry_t*)group, &g_freelist);
irqrestore(flags);
}
else
{
/* No.. deallocate the group structure. Use sched_free() just in case
* this function is executing within an interrupt handler.
*/
irqrestore(flags);
sched_free(group);
}
}
#endif /* CONFIG_NET_IGMP */
