nuttx/net/devif/devif_callback.c
2016-06-11 11:59:51 -06:00

492 lines
15 KiB
C

/****************************************************************************
* net/devif/devif_callback.c
*
* Copyright (C) 2008-2009, 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX 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 THE COPYRIGHT HOLDERS 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 THE
* COPYRIGHT OWNER 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>
#if defined(CONFIG_NET)
#include <stdint.h>
#include <string.h>
#include <debug.h>
#include <assert.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include "netdev/netdev.h"
#include "devif/devif.h"
/****************************************************************************
* Private Data
****************************************************************************/
static struct devif_callback_s g_cbprealloc[CONFIG_NET_NACTIVESOCKETS];
static FAR struct devif_callback_s *g_cbfreelist = NULL;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: devif_callback_free
*
* Description:
* Return a callback container to the free list.
*
* Assumptions:
* This function is called with the network locked.
*
****************************************************************************/
static void devif_callback_free(FAR struct net_driver_s *dev,
FAR struct devif_callback_s *cb,
FAR struct devif_callback_s **list)
{
FAR struct devif_callback_s *prev;
FAR struct devif_callback_s *curr;
net_lock_t save;
if (cb)
{
save = net_lock();
#ifdef CONFIG_DEBUG
/* Check for double freed callbacks */
curr = g_cbfreelist;
while (curr != NULL)
{
DEBUGASSERT(cb != curr);
curr = curr->nxtconn;
}
#endif
/* Remove the callback structure from the device notification list if
* it is supposed to be in the device notification list.
*/
if (dev)
{
/* Find the callback structure in the device event list */
for (prev = NULL, curr = dev->d_devcb;
curr && curr != cb;
prev = curr, curr = curr->nxtdev);
/* Remove the structure from the device event list */
DEBUGASSERT(curr);
if (curr)
{
if (prev)
{
prev->nxtdev = cb->nxtdev;
}
else
{
dev->d_devcb = cb->nxtdev;
}
}
}
/* Remove the callback structure from the data notification list if
* it is supposed to be in the data notification list.
*/
if (list)
{
/* Find the callback structure in the connection event list */
for (prev = NULL, curr = *list;
curr && curr != cb;
prev = curr, curr = curr->nxtconn);
/* Remove the structure from the connection event list */
DEBUGASSERT(curr);
if (curr)
{
if (prev)
{
prev->nxtconn = cb->nxtconn;
}
else
{
*list = cb->nxtconn;
}
}
}
/* Put the structure into the free list */
cb->nxtconn = g_cbfreelist;
cb->nxtdev = NULL;
g_cbfreelist = cb;
net_unlock(save);
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: devif_callback_init
*
* Description:
* Configure the pre-allocated callback structures into a free list.
*
* Assumptions:
* This function is called with interrupts disabled.
*
****************************************************************************/
void devif_callback_init(void)
{
int i;
for (i = 0; i < CONFIG_NET_NACTIVESOCKETS; i++)
{
g_cbprealloc[i].nxtconn = g_cbfreelist;
g_cbfreelist = &g_cbprealloc[i];
}
}
/****************************************************************************
* Function: devif_callback_alloc
*
* Description:
* Allocate a callback container from the free list.
*
* If dev is non-NULL, then this function verifies that the device
* reference is still valid and that the device is still UP status. If
* those conditions are not true, this function will fail to allocate the
* callback.
*
* Assumptions:
* This function is called with the network locked.
*
****************************************************************************/
FAR struct devif_callback_s *
devif_callback_alloc(FAR struct net_driver_s *dev,
FAR struct devif_callback_s **list)
{
FAR struct devif_callback_s *ret;
net_lock_t save;
/* Check the head of the free list */
save = net_lock();
ret = g_cbfreelist;
if (ret)
{
/* Remove the next instance from the head of the free list */
g_cbfreelist = ret->nxtconn;
memset(ret, 0, sizeof(struct devif_callback_s));
/* Add the newly allocated instance to the head of the device event
* list.
*/
if (dev)
{
/* Verify that the device pointer is valid, i.e., that it still
* points to a registered network device and also that the network
* device in in the UP state.
*
* And if it does, should that device also not be in the UP state?
*/
if (!netdev_verify(dev) && (dev->d_flags & IFF_UP) != 0)
{
/* No.. release the callback structure and fail */
devif_callback_free(NULL, NULL, list);
net_unlock(save);
return NULL;
}
ret->nxtdev = dev->d_devcb;
dev->d_devcb = ret;
}
/* Add the newly allocated instance to the head of the specified list */
if (list)
{
ret->nxtconn = *list;
*list = ret;
}
}
#ifdef CONFIG_DEBUG
else
{
nlldbg("Failed to allocate callback\n");
}
#endif
net_unlock(save);
return ret;
}
/****************************************************************************
* Function: devif_conn_callback_free
*
* Description:
* Return a connection/port callback container to the free list.
*
* This function is just a front-end for devif_callback_free(). If the
* dev argument is non-NULL, it will verify that the device reference is
* still valid before attempting to free the callback structure. A
* non-NULL list pointer is assumed to be valid in any case.
*
* The callback structure will be freed in any event.
*
* Assumptions:
* This function is called with the network locked.
*
****************************************************************************/
void devif_conn_callback_free(FAR struct net_driver_s *dev,
FAR struct devif_callback_s *cb,
FAR struct devif_callback_s **list)
{
/* Check if the device pointer is still valid. It could be invalid if, for
* example, the device were unregistered between the time when the callback
* was allocated and the time when the callback was freed.
*/
if (dev && !netdev_verify(dev))
{
/* The device reference is longer valid */
dev = NULL;
}
/* Then free the callback */
devif_callback_free(dev, cb, list);
}
/****************************************************************************
* Function: devif_dev_callback_free
*
* Description:
* Return a device callback container to the free list.
*
* This function is just a front-end for devif_callback_free(). If the
* de argument is non-NULL, it will verify that the device reference is
* still valid before attempting to free the callback structure. It
* differs from devif_conn_callback_free in that connection/port-related
* connections are also associated with the device and, hence, also will
* not be valid if the device pointer is not valid.
*
* The callback structure will be freed in any event.
*
* Assumptions:
* This function is called with the network locked.
*
****************************************************************************/
void devif_dev_callback_free(FAR struct net_driver_s *dev,
FAR struct devif_callback_s *cb)
{
FAR struct devif_callback_s **list;
/* Check if the device pointer is still valid. It could be invalid if, for
* example, the device were unregistered between the time when the callback
* was allocated and the time when the callback was freed.
*/
if (dev && netdev_verify(dev))
{
/* The device reference is valid.. the use the list pointer in the
* device structure as well.
*/
list = &dev->d_conncb;
}
else
{
/* The device reference is longer valid */
dev = NULL;
list = NULL;
}
/* Then free the callback */
devif_callback_free(dev, cb, list);
}
/****************************************************************************
* Function: devif_conn_event
*
* Description:
* Execute a list of callbacks using the packet event chain.
*
* Input parameters:
* dev - The network device state structure associated with the network
* device that initiated the callback event.
* pvconn - Holds a reference to the TCP connection structure or the UDP
* port structure. May be NULL if the even is not related to a TCP
* connection or UDP port.
* flags - The bit set of events to be notified.
* list - The list to traverse in performing the notifications
*
* Returned value:
* The updated flags as modified by the callback functions.
*
* Assumptions:
* This function is called with the network locked.
*
****************************************************************************/
uint16_t devif_conn_event(FAR struct net_driver_s *dev, void *pvconn,
uint16_t flags, FAR struct devif_callback_s *list)
{
FAR struct devif_callback_s *next;
net_lock_t save;
/* Loop for each callback in the list and while there are still events
* set in the flags set.
*/
save = net_lock();
while (list && flags)
{
/* Save the pointer to the next callback in the lists. This is done
* because the callback action might delete the entry pointed to by
* list.
*/
next = list->nxtconn;
/* Check if this callback handles any of the events in the flag set */
if (list->event && (flags & list->flags) != 0)
{
/* Yes.. perform the callback. Actions perform by the callback
* may delete the current list entry or add a new list entry to
* beginning of the list (which will be ignored on this pass)
*/
nllinfo("Call event=%p with flags=%04x\n", list->event, flags);
flags = list->event(dev, pvconn, list->priv, flags);
}
/* Set up for the next time through the loop */
list = next;
}
net_unlock(save);
return flags;
}
/****************************************************************************
* Function: devif_dev_event
*
* Description:
* Execute a list of callbacks using the device event chain.
*
* Input parameters:
* dev - The network device state structure associated with the network
* device that initiated the callback event.
* pvconn - Holds a reference to the TCP connection structure or the UDP
* port structure. May be NULL if the even is not related to a TCP
* connection or UDP port.
* flags - The bit set of events to be notified.
*
* Returned value:
* The updated flags as modified by the callback functions.
*
* Assumptions:
* This function is called with the network locked.
*
****************************************************************************/
uint16_t devif_dev_event(FAR struct net_driver_s *dev, void *pvconn,
uint16_t flags)
{
FAR struct devif_callback_s *cb;
FAR struct devif_callback_s *next;
net_lock_t save;
/* Loop for each callback in the list and while there are still events
* set in the flags set.
*/
save = net_lock();
for (cb = dev->d_devcb; cb != NULL && flags != 0; cb = next)
{
/* Save the pointer to the next callback in the lists. This is done
* because the callback action might delete the entry pointed to by
* list.
*/
next = cb->nxtdev;
/* Check if this callback handles any of the events in the flag set */
if (cb->event && (flags & cb->flags) != 0)
{
/* Yes.. perform the callback. Actions perform by the callback
* may delete the current list entry or add a new list entry to
* beginning of the list (which will be ignored on this pass)
*/
nllinfo("Call event=%p with flags=%04x\n", cb->event, flags);
flags = cb->event(dev, pvconn, cb->priv, flags);
}
/* Set up for the next time through the loop */
cb = next;
}
net_unlock(save);
return flags;
}
#endif /* CONFIG_NET */