diff options
author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
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committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /drivers/vhost/net.c | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'drivers/vhost/net.c')
-rw-r--r-- | drivers/vhost/net.c | 792 |
1 files changed, 792 insertions, 0 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c new file mode 100644 index 00000000..e224a92b --- /dev/null +++ b/drivers/vhost/net.c @@ -0,0 +1,792 @@ +/* Copyright (C) 2009 Red Hat, Inc. + * Author: Michael S. Tsirkin <mst@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. + * + * virtio-net server in host kernel. + */ + +#include <linux/compat.h> +#include <linux/eventfd.h> +#include <linux/vhost.h> +#include <linux/virtio_net.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/workqueue.h> +#include <linux/rcupdate.h> +#include <linux/file.h> +#include <linux/slab.h> + +#include <linux/net.h> +#include <linux/if_packet.h> +#include <linux/if_arp.h> +#include <linux/if_tun.h> +#include <linux/if_macvlan.h> + +#include <net/sock.h> + +#include "vhost.h" + +/* Max number of bytes transferred before requeueing the job. + * Using this limit prevents one virtqueue from starving others. */ +#define VHOST_NET_WEIGHT 0x80000 + +enum { + VHOST_NET_VQ_RX = 0, + VHOST_NET_VQ_TX = 1, + VHOST_NET_VQ_MAX = 2, +}; + +enum vhost_net_poll_state { + VHOST_NET_POLL_DISABLED = 0, + VHOST_NET_POLL_STARTED = 1, + VHOST_NET_POLL_STOPPED = 2, +}; + +struct vhost_net { + struct vhost_dev dev; + struct vhost_virtqueue vqs[VHOST_NET_VQ_MAX]; + struct vhost_poll poll[VHOST_NET_VQ_MAX]; + /* Tells us whether we are polling a socket for TX. + * We only do this when socket buffer fills up. + * Protected by tx vq lock. */ + enum vhost_net_poll_state tx_poll_state; +}; + +/* Pop first len bytes from iovec. Return number of segments used. */ +static int move_iovec_hdr(struct iovec *from, struct iovec *to, + size_t len, int iov_count) +{ + int seg = 0; + size_t size; + + while (len && seg < iov_count) { + size = min(from->iov_len, len); + to->iov_base = from->iov_base; + to->iov_len = size; + from->iov_len -= size; + from->iov_base += size; + len -= size; + ++from; + ++to; + ++seg; + } + return seg; +} +/* Copy iovec entries for len bytes from iovec. */ +static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, + size_t len, int iovcount) +{ + int seg = 0; + size_t size; + + while (len && seg < iovcount) { + size = min(from->iov_len, len); + to->iov_base = from->iov_base; + to->iov_len = size; + len -= size; + ++from; + ++to; + ++seg; + } +} + +/* Caller must have TX VQ lock */ +static void tx_poll_stop(struct vhost_net *net) +{ + if (likely(net->tx_poll_state != VHOST_NET_POLL_STARTED)) + return; + vhost_poll_stop(net->poll + VHOST_NET_VQ_TX); + net->tx_poll_state = VHOST_NET_POLL_STOPPED; +} + +/* Caller must have TX VQ lock */ +static void tx_poll_start(struct vhost_net *net, struct socket *sock) +{ + if (unlikely(net->tx_poll_state != VHOST_NET_POLL_STOPPED)) + return; + vhost_poll_start(net->poll + VHOST_NET_VQ_TX, sock->file); + net->tx_poll_state = VHOST_NET_POLL_STARTED; +} + +/* Expects to be always run from workqueue - which acts as + * read-size critical section for our kind of RCU. */ +static void handle_tx(struct vhost_net *net) +{ + struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; + unsigned out, in, s; + int head; + struct msghdr msg = { + .msg_name = NULL, + .msg_namelen = 0, + .msg_control = NULL, + .msg_controllen = 0, + .msg_iov = vq->iov, + .msg_flags = MSG_DONTWAIT, + }; + size_t len, total_len = 0; + int err, wmem; + size_t hdr_size; + struct socket *sock; + + /* TODO: check that we are running from vhost_worker? */ + sock = rcu_dereference_check(vq->private_data, 1); + if (!sock) + return; + + wmem = atomic_read(&sock->sk->sk_wmem_alloc); + if (wmem >= sock->sk->sk_sndbuf) { + mutex_lock(&vq->mutex); + tx_poll_start(net, sock); + mutex_unlock(&vq->mutex); + return; + } + + mutex_lock(&vq->mutex); + vhost_disable_notify(&net->dev, vq); + + if (wmem < sock->sk->sk_sndbuf / 2) + tx_poll_stop(net); + hdr_size = vq->vhost_hlen; + + for (;;) { + head = vhost_get_vq_desc(&net->dev, vq, vq->iov, + ARRAY_SIZE(vq->iov), + &out, &in, + NULL, NULL); + /* On error, stop handling until the next kick. */ + if (unlikely(head < 0)) + break; + /* Nothing new? Wait for eventfd to tell us they refilled. */ + if (head == vq->num) { + wmem = atomic_read(&sock->sk->sk_wmem_alloc); + if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { + tx_poll_start(net, sock); + set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); + break; + } + if (unlikely(vhost_enable_notify(&net->dev, vq))) { + vhost_disable_notify(&net->dev, vq); + continue; + } + break; + } + if (in) { + vq_err(vq, "Unexpected descriptor format for TX: " + "out %d, int %d\n", out, in); + break; + } + /* Skip header. TODO: support TSO. */ + s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); + msg.msg_iovlen = out; + len = iov_length(vq->iov, out); + /* Sanity check */ + if (!len) { + vq_err(vq, "Unexpected header len for TX: " + "%zd expected %zd\n", + iov_length(vq->hdr, s), hdr_size); + break; + } + /* TODO: Check specific error and bomb out unless ENOBUFS? */ + err = sock->ops->sendmsg(NULL, sock, &msg, len); + if (unlikely(err < 0)) { + vhost_discard_vq_desc(vq, 1); + tx_poll_start(net, sock); + break; + } + if (err != len) + pr_debug("Truncated TX packet: " + " len %d != %zd\n", err, len); + vhost_add_used_and_signal(&net->dev, vq, head, 0); + total_len += len; + if (unlikely(total_len >= VHOST_NET_WEIGHT)) { + vhost_poll_queue(&vq->poll); + break; + } + } + + mutex_unlock(&vq->mutex); +} + +static int peek_head_len(struct sock *sk) +{ + struct sk_buff *head; + int len = 0; + unsigned long flags; + + spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); + head = skb_peek(&sk->sk_receive_queue); + if (likely(head)) + len = head->len; + spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); + return len; +} + +/* This is a multi-buffer version of vhost_get_desc, that works if + * vq has read descriptors only. + * @vq - the relevant virtqueue + * @datalen - data length we'll be reading + * @iovcount - returned count of io vectors we fill + * @log - vhost log + * @log_num - log offset + * @quota - headcount quota, 1 for big buffer + * returns number of buffer heads allocated, negative on error + */ +static int get_rx_bufs(struct vhost_virtqueue *vq, + struct vring_used_elem *heads, + int datalen, + unsigned *iovcount, + struct vhost_log *log, + unsigned *log_num, + unsigned int quota) +{ + unsigned int out, in; + int seg = 0; + int headcount = 0; + unsigned d; + int r, nlogs = 0; + + while (datalen > 0 && headcount < quota) { + if (unlikely(seg >= UIO_MAXIOV)) { + r = -ENOBUFS; + goto err; + } + d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, + ARRAY_SIZE(vq->iov) - seg, &out, + &in, log, log_num); + if (d == vq->num) { + r = 0; + goto err; + } + if (unlikely(out || in <= 0)) { + vq_err(vq, "unexpected descriptor format for RX: " + "out %d, in %d\n", out, in); + r = -EINVAL; + goto err; + } + if (unlikely(log)) { + nlogs += *log_num; + log += *log_num; + } + heads[headcount].id = d; + heads[headcount].len = iov_length(vq->iov + seg, in); + datalen -= heads[headcount].len; + ++headcount; + seg += in; + } + heads[headcount - 1].len += datalen; + *iovcount = seg; + if (unlikely(log)) + *log_num = nlogs; + return headcount; +err: + vhost_discard_vq_desc(vq, headcount); + return r; +} + +/* Expects to be always run from workqueue - which acts as + * read-size critical section for our kind of RCU. */ +static void handle_rx(struct vhost_net *net) +{ + struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; + unsigned uninitialized_var(in), log; + struct vhost_log *vq_log; + struct msghdr msg = { + .msg_name = NULL, + .msg_namelen = 0, + .msg_control = NULL, /* FIXME: get and handle RX aux data. */ + .msg_controllen = 0, + .msg_iov = vq->iov, + .msg_flags = MSG_DONTWAIT, + }; + struct virtio_net_hdr_mrg_rxbuf hdr = { + .hdr.flags = 0, + .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE + }; + size_t total_len = 0; + int err, headcount, mergeable; + size_t vhost_hlen, sock_hlen; + size_t vhost_len, sock_len; + /* TODO: check that we are running from vhost_worker? */ + struct socket *sock = rcu_dereference_check(vq->private_data, 1); + + if (!sock) + return; + + mutex_lock(&vq->mutex); + vhost_disable_notify(&net->dev, vq); + vhost_hlen = vq->vhost_hlen; + sock_hlen = vq->sock_hlen; + + vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? + vq->log : NULL; + mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); + + while ((sock_len = peek_head_len(sock->sk))) { + sock_len += sock_hlen; + vhost_len = sock_len + vhost_hlen; + headcount = get_rx_bufs(vq, vq->heads, vhost_len, + &in, vq_log, &log, + likely(mergeable) ? UIO_MAXIOV : 1); + /* On error, stop handling until the next kick. */ + if (unlikely(headcount < 0)) + break; + /* OK, now we need to know about added descriptors. */ + if (!headcount) { + if (unlikely(vhost_enable_notify(&net->dev, vq))) { + /* They have slipped one in as we were + * doing that: check again. */ + vhost_disable_notify(&net->dev, vq); + continue; + } + /* Nothing new? Wait for eventfd to tell us + * they refilled. */ + break; + } + /* We don't need to be notified again. */ + if (unlikely((vhost_hlen))) + /* Skip header. TODO: support TSO. */ + move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in); + else + /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: + * needed because recvmsg can modify msg_iov. */ + copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in); + msg.msg_iovlen = in; + err = sock->ops->recvmsg(NULL, sock, &msg, + sock_len, MSG_DONTWAIT | MSG_TRUNC); + /* Userspace might have consumed the packet meanwhile: + * it's not supposed to do this usually, but might be hard + * to prevent. Discard data we got (if any) and keep going. */ + if (unlikely(err != sock_len)) { + pr_debug("Discarded rx packet: " + " len %d, expected %zd\n", err, sock_len); + vhost_discard_vq_desc(vq, headcount); + continue; + } + if (unlikely(vhost_hlen) && + memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0, + vhost_hlen)) { + vq_err(vq, "Unable to write vnet_hdr at addr %p\n", + vq->iov->iov_base); + break; + } + /* TODO: Should check and handle checksum. */ + if (likely(mergeable) && + memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, + offsetof(typeof(hdr), num_buffers), + sizeof hdr.num_buffers)) { + vq_err(vq, "Failed num_buffers write"); + vhost_discard_vq_desc(vq, headcount); + break; + } + vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, + headcount); + if (unlikely(vq_log)) + vhost_log_write(vq, vq_log, log, vhost_len); + total_len += vhost_len; + if (unlikely(total_len >= VHOST_NET_WEIGHT)) { + vhost_poll_queue(&vq->poll); + break; + } + } + + mutex_unlock(&vq->mutex); +} + +static void handle_tx_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); + + handle_tx(net); +} + +static void handle_rx_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); + + handle_rx(net); +} + +static void handle_tx_net(struct vhost_work *work) +{ + struct vhost_net *net = container_of(work, struct vhost_net, + poll[VHOST_NET_VQ_TX].work); + handle_tx(net); +} + +static void handle_rx_net(struct vhost_work *work) +{ + struct vhost_net *net = container_of(work, struct vhost_net, + poll[VHOST_NET_VQ_RX].work); + handle_rx(net); +} + +static int vhost_net_open(struct inode *inode, struct file *f) +{ + struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); + struct vhost_dev *dev; + int r; + + if (!n) + return -ENOMEM; + + dev = &n->dev; + n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; + n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; + r = vhost_dev_init(dev, n->vqs, VHOST_NET_VQ_MAX); + if (r < 0) { + kfree(n); + return r; + } + + vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); + vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); + n->tx_poll_state = VHOST_NET_POLL_DISABLED; + + f->private_data = n; + + return 0; +} + +static void vhost_net_disable_vq(struct vhost_net *n, + struct vhost_virtqueue *vq) +{ + if (!vq->private_data) + return; + if (vq == n->vqs + VHOST_NET_VQ_TX) { + tx_poll_stop(n); + n->tx_poll_state = VHOST_NET_POLL_DISABLED; + } else + vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); +} + +static void vhost_net_enable_vq(struct vhost_net *n, + struct vhost_virtqueue *vq) +{ + struct socket *sock; + + sock = rcu_dereference_protected(vq->private_data, + lockdep_is_held(&vq->mutex)); + if (!sock) + return; + if (vq == n->vqs + VHOST_NET_VQ_TX) { + n->tx_poll_state = VHOST_NET_POLL_STOPPED; + tx_poll_start(n, sock); + } else + vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); +} + +static struct socket *vhost_net_stop_vq(struct vhost_net *n, + struct vhost_virtqueue *vq) +{ + struct socket *sock; + + mutex_lock(&vq->mutex); + sock = rcu_dereference_protected(vq->private_data, + lockdep_is_held(&vq->mutex)); + vhost_net_disable_vq(n, vq); + rcu_assign_pointer(vq->private_data, NULL); + mutex_unlock(&vq->mutex); + return sock; +} + +static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, + struct socket **rx_sock) +{ + *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); + *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); +} + +static void vhost_net_flush_vq(struct vhost_net *n, int index) +{ + vhost_poll_flush(n->poll + index); + vhost_poll_flush(&n->dev.vqs[index].poll); +} + +static void vhost_net_flush(struct vhost_net *n) +{ + vhost_net_flush_vq(n, VHOST_NET_VQ_TX); + vhost_net_flush_vq(n, VHOST_NET_VQ_RX); +} + +static int vhost_net_release(struct inode *inode, struct file *f) +{ + struct vhost_net *n = f->private_data; + struct socket *tx_sock; + struct socket *rx_sock; + + vhost_net_stop(n, &tx_sock, &rx_sock); + vhost_net_flush(n); + vhost_dev_cleanup(&n->dev); + if (tx_sock) + fput(tx_sock->file); + if (rx_sock) + fput(rx_sock->file); + /* We do an extra flush before freeing memory, + * since jobs can re-queue themselves. */ + vhost_net_flush(n); + kfree(n); + return 0; +} + +static struct socket *get_raw_socket(int fd) +{ + struct { + struct sockaddr_ll sa; + char buf[MAX_ADDR_LEN]; + } uaddr; + int uaddr_len = sizeof uaddr, r; + struct socket *sock = sockfd_lookup(fd, &r); + + if (!sock) + return ERR_PTR(-ENOTSOCK); + + /* Parameter checking */ + if (sock->sk->sk_type != SOCK_RAW) { + r = -ESOCKTNOSUPPORT; + goto err; + } + + r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, + &uaddr_len, 0); + if (r) + goto err; + + if (uaddr.sa.sll_family != AF_PACKET) { + r = -EPFNOSUPPORT; + goto err; + } + return sock; +err: + fput(sock->file); + return ERR_PTR(r); +} + +static struct socket *get_tap_socket(int fd) +{ + struct file *file = fget(fd); + struct socket *sock; + + if (!file) + return ERR_PTR(-EBADF); + sock = tun_get_socket(file); + if (!IS_ERR(sock)) + return sock; + sock = macvtap_get_socket(file); + if (IS_ERR(sock)) + fput(file); + return sock; +} + +static struct socket *get_socket(int fd) +{ + struct socket *sock; + + /* special case to disable backend */ + if (fd == -1) + return NULL; + sock = get_raw_socket(fd); + if (!IS_ERR(sock)) + return sock; + sock = get_tap_socket(fd); + if (!IS_ERR(sock)) + return sock; + return ERR_PTR(-ENOTSOCK); +} + +static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd) +{ + struct socket *sock, *oldsock; + struct vhost_virtqueue *vq; + int r; + + mutex_lock(&n->dev.mutex); + r = vhost_dev_check_owner(&n->dev); + if (r) + goto err; + + if (index >= VHOST_NET_VQ_MAX) { + r = -ENOBUFS; + goto err; + } + vq = n->vqs + index; + mutex_lock(&vq->mutex); + + /* Verify that ring has been setup correctly. */ + if (!vhost_vq_access_ok(vq)) { + r = -EFAULT; + goto err_vq; + } + sock = get_socket(fd); + if (IS_ERR(sock)) { + r = PTR_ERR(sock); + goto err_vq; + } + + /* start polling new socket */ + oldsock = rcu_dereference_protected(vq->private_data, + lockdep_is_held(&vq->mutex)); + if (sock != oldsock) { + vhost_net_disable_vq(n, vq); + rcu_assign_pointer(vq->private_data, sock); + vhost_net_enable_vq(n, vq); + } + + mutex_unlock(&vq->mutex); + + if (oldsock) { + vhost_net_flush_vq(n, index); + fput(oldsock->file); + } + + mutex_unlock(&n->dev.mutex); + return 0; + +err_vq: + mutex_unlock(&vq->mutex); +err: + mutex_unlock(&n->dev.mutex); + return r; +} + +static long vhost_net_reset_owner(struct vhost_net *n) +{ + struct socket *tx_sock = NULL; + struct socket *rx_sock = NULL; + long err; + + mutex_lock(&n->dev.mutex); + err = vhost_dev_check_owner(&n->dev); + if (err) + goto done; + vhost_net_stop(n, &tx_sock, &rx_sock); + vhost_net_flush(n); + err = vhost_dev_reset_owner(&n->dev); +done: + mutex_unlock(&n->dev.mutex); + if (tx_sock) + fput(tx_sock->file); + if (rx_sock) + fput(rx_sock->file); + return err; +} + +static int vhost_net_set_features(struct vhost_net *n, u64 features) +{ + size_t vhost_hlen, sock_hlen, hdr_len; + int i; + + hdr_len = (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) ? + sizeof(struct virtio_net_hdr_mrg_rxbuf) : + sizeof(struct virtio_net_hdr); + if (features & (1 << VHOST_NET_F_VIRTIO_NET_HDR)) { + /* vhost provides vnet_hdr */ + vhost_hlen = hdr_len; + sock_hlen = 0; + } else { + /* socket provides vnet_hdr */ + vhost_hlen = 0; + sock_hlen = hdr_len; + } + mutex_lock(&n->dev.mutex); + if ((features & (1 << VHOST_F_LOG_ALL)) && + !vhost_log_access_ok(&n->dev)) { + mutex_unlock(&n->dev.mutex); + return -EFAULT; + } + n->dev.acked_features = features; + smp_wmb(); + for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + mutex_lock(&n->vqs[i].mutex); + n->vqs[i].vhost_hlen = vhost_hlen; + n->vqs[i].sock_hlen = sock_hlen; + mutex_unlock(&n->vqs[i].mutex); + } + vhost_net_flush(n); + mutex_unlock(&n->dev.mutex); + return 0; +} + +static long vhost_net_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + struct vhost_net *n = f->private_data; + void __user *argp = (void __user *)arg; + u64 __user *featurep = argp; + struct vhost_vring_file backend; + u64 features; + int r; + + switch (ioctl) { + case VHOST_NET_SET_BACKEND: + if (copy_from_user(&backend, argp, sizeof backend)) + return -EFAULT; + return vhost_net_set_backend(n, backend.index, backend.fd); + case VHOST_GET_FEATURES: + features = VHOST_FEATURES; + if (copy_to_user(featurep, &features, sizeof features)) + return -EFAULT; + return 0; + case VHOST_SET_FEATURES: + if (copy_from_user(&features, featurep, sizeof features)) + return -EFAULT; + if (features & ~VHOST_FEATURES) + return -EOPNOTSUPP; + return vhost_net_set_features(n, features); + case VHOST_RESET_OWNER: + return vhost_net_reset_owner(n); + default: + mutex_lock(&n->dev.mutex); + r = vhost_dev_ioctl(&n->dev, ioctl, arg); + vhost_net_flush(n); + mutex_unlock(&n->dev.mutex); + return r; + } +} + +#ifdef CONFIG_COMPAT +static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + return vhost_net_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); +} +#endif + +static const struct file_operations vhost_net_fops = { + .owner = THIS_MODULE, + .release = vhost_net_release, + .unlocked_ioctl = vhost_net_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vhost_net_compat_ioctl, +#endif + .open = vhost_net_open, + .llseek = noop_llseek, +}; + +static struct miscdevice vhost_net_misc = { + MISC_DYNAMIC_MINOR, + "vhost-net", + &vhost_net_fops, +}; + +static int vhost_net_init(void) +{ + return misc_register(&vhost_net_misc); +} +module_init(vhost_net_init); + +static void vhost_net_exit(void) +{ + misc_deregister(&vhost_net_misc); +} +module_exit(vhost_net_exit); + +MODULE_VERSION("0.0.1"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Michael S. Tsirkin"); +MODULE_DESCRIPTION("Host kernel accelerator for virtio net"); |