linux-imx

/*

 * Copyright (C) ST-Ericsson AB 2010

 * Author:  Sjur Brendeland

 * License terms: GNU General Public License (GPL) version 2

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__

​

#include <linux/fs.h>

#include <linux/init.h>

#include <linux/module.h>

#include <linux/sched/signal.h>

#include <linux/spinlock.h>

#include <linux/mutex.h>

#include <linux/list.h>

#include <linux/wait.h>

#include <linux/poll.h>

#include <linux/tcp.h>

#include <linux/uaccess.h>

#include <linux/debugfs.h>

#include <linux/caif/caif_socket.h>

#include <linux/pkt_sched.h>

#include <net/sock.h>

#include <net/tcp_states.h>

#include <net/caif/caif_layer.h>

#include <net/caif/caif_dev.h>

#include <net/caif/cfpkt.h>

​

MODULE_LICENSE("GPL");

MODULE_ALIAS_NETPROTO(AF_CAIF);

​

/*

 * CAIF state is re-using the TCP socket states.

 * caif_states stored in sk_state reflect the state as reported by

 * the CAIF stack, while sk_socket->state is the state of the socket.

 */

enum caif_states {

    CAIF_CONNECTED      = TCP_ESTABLISHED,

    CAIF_CONNECTING = TCP_SYN_SENT,

    CAIF_DISCONNECTED   = TCP_CLOSE

};

​

#define TX_FLOW_ON_BIT  1

#define RX_FLOW_ON_BIT  2

​

struct caifsock {

    struct sock sk; /* must be first member */

    struct cflayer layer;

    u32 flow_state;

    struct caif_connect_request conn_req;

    struct mutex readlock;

    struct dentry *debugfs_socket_dir;

    int headroom, tailroom, maxframe;

};

​

static int rx_flow_is_on(struct caifsock *cf_sk)

{

    return test_bit(RX_FLOW_ON_BIT,

            (void *) &cf_sk->flow_state);

}

​

static int tx_flow_is_on(struct caifsock *cf_sk)

{

    return test_bit(TX_FLOW_ON_BIT,

            (void *) &cf_sk->flow_state);

}

​

static void set_rx_flow_off(struct caifsock *cf_sk)

{

     clear_bit(RX_FLOW_ON_BIT,

         (void *) &cf_sk->flow_state);

}

​

static void set_rx_flow_on(struct caifsock *cf_sk)

{

     set_bit(RX_FLOW_ON_BIT,

            (void *) &cf_sk->flow_state);

}

​

static void set_tx_flow_off(struct caifsock *cf_sk)

{

     clear_bit(TX_FLOW_ON_BIT,

        (void *) &cf_sk->flow_state);

}

​

static void set_tx_flow_on(struct caifsock *cf_sk)

{

     set_bit(TX_FLOW_ON_BIT,

        (void *) &cf_sk->flow_state);

}

​

static void caif_read_lock(struct sock *sk)