linux-imx

/*

 * vhost transport for vsock

 *

 * Copyright (C) 2013-2015 Red Hat, Inc.

 * Author: Asias He <asias@redhat.com>

 *         Stefan Hajnoczi <stefanha@redhat.com>

 *

 * This work is licensed under the terms of the GNU GPL, version 2.

 */

#include <linux/miscdevice.h>

#include <linux/atomic.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/vmalloc.h>

#include <net/sock.h>

#include <linux/virtio_vsock.h>

#include <linux/vhost.h>

#include <linux/hashtable.h>

​

#include <net/af_vsock.h>

#include "vhost.h"

​

#define VHOST_VSOCK_DEFAULT_HOST_CID    2

​

enum {

    VHOST_VSOCK_FEATURES = VHOST_FEATURES,

};

​

/* Used to track all the vhost_vsock instances on the system. */

static DEFINE_MUTEX(vhost_vsock_mutex);

static DEFINE_READ_MOSTLY_HASHTABLE(vhost_vsock_hash, 8);

​

struct vhost_vsock {

    struct vhost_dev dev;

    struct vhost_virtqueue vqs[2];

​

    /* Link to global vhost_vsock_hash, writes use vhost_vsock_mutex */

    struct hlist_node hash;

​

    struct vhost_work send_pkt_work;

    spinlock_t send_pkt_list_lock;

    struct list_head send_pkt_list; /* host->guest pending packets */

​

    atomic_t queued_replies;

​

    u32 guest_cid;

};

​

static u32 vhost_transport_get_local_cid(void)

{

    return VHOST_VSOCK_DEFAULT_HOST_CID;

}

​

/* Callers that dereference the return value must hold vhost_vsock_mutex or the

 * RCU read lock.

 */

static struct vhost_vsock *vhost_vsock_get(u32 guest_cid)

{

    struct vhost_vsock *vsock;

​

    hash_for_each_possible_rcu(vhost_vsock_hash, vsock, hash, guest_cid) {

        u32 other_cid = vsock->guest_cid;

​