source: mainline/uspace/lib/net/generic/packet_remote.c@ 24cf31f1

/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup libnet
 * @{
 */

/** @file
 * Packet client interface implementation for remote modules.
 * @see packet_client.h
 */

#include <async.h>
#include <errno.h>
#include <ipc/packet.h>
#include <sys/mman.h>

#include <packet_client.h>
#include <packet_remote.h>

#include <net/packet.h>
#include <net/packet_header.h>

/** Obtain the packet from the packet server as the shared memory block.
 *
 * Create the local packet mapping as well.
 *
 * @param[in]  sess      Packet server module session.
 * @param[out] packet    Packet reference pointer to store the received
 *                       packet reference.
 * @param[in]  packet_id Packet identifier.
 * @param[in]  size      Packet total size in bytes.
 *
 * @return EOK on success.
 * @return Other error codes as defined for the pm_add() function.
 * @return Other error codes as defined for the async_share_in_start()
 *         function.
 *
 */
static int packet_return(async_sess_t *sess, packet_t **packet,
    packet_id_t packet_id, size_t size)
{
        *packet = (packet_t *) as_get_mappable_page(size);
        
        async_exch_t *exch = async_exchange_begin(sess);
        ipc_call_t answer;
        aid_t message = async_send_1(exch, NET_PACKET_GET, packet_id, &answer);
        int rc = async_share_in_start_0_0(exch, *packet, size);
        async_exchange_end(exch);
        
        sysarg_t result;
        async_wait_for(message, &result);
        
        if (rc != EOK)
                return rc;
        
        rc = pm_add(*packet);
        if (rc != EOK) {
                munmap(*packet, size);
                return rc;
        }
        
        return result;
}

/** Translate the packet identifier to the packet reference.
 *
 * Try to find mapping first. The packet server is asked to share
 * the packet if the mapping is not present.
 *
 * @param[in]  sess      Packet server module session.
 * @param[out] packet    Packet reference.
 * @param[in]  packet_id Packet identifier.
 *
 * @return EOK on success.
 * @return EINVAL if the packet parameter is NULL.
 * @return Other error codes as defined for the NET_PACKET_GET_SIZE
 *         message.
 * @return Other error codes as defined for the packet_return()
 *         function.
 *
 */
int packet_translate_remote(async_sess_t *sess, packet_t **packet,
    packet_id_t packet_id)
{
        if (!packet)
                return EINVAL;
        
        *packet = pm_find(packet_id);
        if (*packet == NULL) {
                async_exch_t *exch = async_exchange_begin(sess);
                sysarg_t size;
                int rc = async_req_1_1(exch, NET_PACKET_GET_SIZE, packet_id,
                    &size);
                async_exchange_end(exch);
                
                if (rc != EOK)
                        return rc;
                
                rc = packet_return(sess, packet, packet_id, size);
                if (rc != EOK)
                        return rc;
        }
        
        if ((*packet != NULL) && ((*packet)->next)) {
                packet_t *next;
                return packet_translate_remote(sess, &next, (*packet)->next);
        }
        
        return EOK;
}

/** Obtain the packet of given dimensions.
 *
 * Contact the packet server to return the appropriate packet.
 *
 * @param[in] sess        Packet server module session.
 * @param[in] addr_len    Source and destination addresses maximal length
 *                        in bytes.
 * @param[in] max_prefix  Maximal prefix length in bytes.
 * @param[in] max_content Maximal content length in bytes.
 * @param[in] max_suffix  Maximal suffix length in bytes.
 *
 * @return The packet reference.
 * @return NULL on error.
 *
 */
packet_t *packet_get_4_remote(async_sess_t *sess, size_t max_content,
    size_t addr_len, size_t max_prefix, size_t max_suffix)
{
        async_exch_t *exch = async_exchange_begin(sess);
        sysarg_t packet_id;
        sysarg_t size;
        int rc = async_req_4_2(exch, NET_PACKET_CREATE_4, max_content, addr_len,
            max_prefix, max_suffix, &packet_id, &size);
        async_exchange_end(exch);
        
        if (rc != EOK)
                return NULL;
        
        packet_t *packet = pm_find(packet_id);
        if (!packet) {
                rc = packet_return(sess, &packet, packet_id, size);
                if (rc != EOK)
                        return NULL;
        }
        
        return packet;
}

/** Obtain the packet of given content size.
 *
 * Contact the packet server to return the appropriate packet.
 *
 * @param[in] sess    Packet server module session.
 * @param[in] content Maximal content length in bytes.
 *
 * @return The packet reference.
 * @return NULL on error.
 *
 */
packet_t *packet_get_1_remote(async_sess_t *sess, size_t content)
{
        async_exch_t *exch = async_exchange_begin(sess);
        sysarg_t packet_id;
        sysarg_t size;
        int rc = async_req_1_2(exch, NET_PACKET_CREATE_1, content, &packet_id,
            &size);
        async_exchange_end(exch);
        
        if (rc != EOK)
                return NULL;
        
        packet_t *packet = pm_find(packet_id);
        if (!packet) {
                rc = packet_return(sess, &packet, packet_id, size);
                if (rc != EOK)
                        return NULL;
        }
        
        return packet;
}

/** Release the packet queue.
 *
 * All packets in the queue are marked as free for use.
 * The packet queue may be one packet only.
 * The module should not use the packets after this point until they are
 * received or obtained again.
 *
 * @param[in] sess      Packet server module session.
 * @param[in] packet_id Packet identifier.
 *
 */
void pq_release_remote(async_sess_t *sess, packet_id_t packet_id)
{
        async_exch_t *exch = async_exchange_begin(sess);
        async_msg_1(exch, NET_PACKET_RELEASE, packet_id);
        async_exchange_end(exch);
}

/** @}
 */