mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-16 16:54:20 +08:00
Merge branch 'vhost-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
This commit is contained in:
David S. Miller
commit
4fc6eb7d35
@ -74,6 +74,22 @@ static int move_iovec_hdr(struct iovec *from, struct iovec *to,
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}
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return seg;
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}
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/* Copy iovec entries for len bytes from iovec. */
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static void copy_iovec_hdr(const struct iovec *from, struct iovec *to,
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size_t len, int iovcount)
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{
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int seg = 0;
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size_t size;
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while (len && seg < iovcount) {
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size = min(from->iov_len, len);
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to->iov_base = from->iov_base;
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to->iov_len = size;
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len -= size;
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++from;
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++to;
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++seg;
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}
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}
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/* Caller must have TX VQ lock */
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static void tx_poll_stop(struct vhost_net *net)
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@ -129,7 +145,7 @@ static void handle_tx(struct vhost_net *net)
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if (wmem < sock->sk->sk_sndbuf / 2)
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tx_poll_stop(net);
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hdr_size = vq->hdr_size;
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hdr_size = vq->vhost_hlen;
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for (;;) {
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head = vhost_get_vq_desc(&net->dev, vq, vq->iov,
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@ -172,7 +188,7 @@ static void handle_tx(struct vhost_net *net)
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/* TODO: Check specific error and bomb out unless ENOBUFS? */
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err = sock->ops->sendmsg(NULL, sock, &msg, len);
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if (unlikely(err < 0)) {
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vhost_discard_vq_desc(vq);
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vhost_discard_vq_desc(vq, 1);
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tx_poll_start(net, sock);
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break;
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}
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@ -191,9 +207,82 @@ static void handle_tx(struct vhost_net *net)
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unuse_mm(net->dev.mm);
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}
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static int peek_head_len(struct sock *sk)
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{
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struct sk_buff *head;
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int len = 0;
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lock_sock(sk);
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head = skb_peek(&sk->sk_receive_queue);
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if (head)
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len = head->len;
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release_sock(sk);
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return len;
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}
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/* This is a multi-buffer version of vhost_get_desc, that works if
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* vq has read descriptors only.
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* @vq - the relevant virtqueue
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* @datalen - data length we'll be reading
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* @iovcount - returned count of io vectors we fill
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* @log - vhost log
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* @log_num - log offset
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* returns number of buffer heads allocated, negative on error
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*/
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static int get_rx_bufs(struct vhost_virtqueue *vq,
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struct vring_used_elem *heads,
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int datalen,
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unsigned *iovcount,
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struct vhost_log *log,
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unsigned *log_num)
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{
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unsigned int out, in;
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int seg = 0;
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int headcount = 0;
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unsigned d;
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int r, nlogs = 0;
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while (datalen > 0) {
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if (unlikely(headcount >= VHOST_NET_MAX_SG)) {
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r = -ENOBUFS;
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goto err;
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}
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d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg,
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ARRAY_SIZE(vq->iov) - seg, &out,
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&in, log, log_num);
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if (d == vq->num) {
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r = 0;
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goto err;
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}
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if (unlikely(out || in <= 0)) {
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vq_err(vq, "unexpected descriptor format for RX: "
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"out %d, in %d\n", out, in);
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r = -EINVAL;
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goto err;
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}
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if (unlikely(log)) {
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nlogs += *log_num;
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log += *log_num;
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}
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heads[headcount].id = d;
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heads[headcount].len = iov_length(vq->iov + seg, in);
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datalen -= heads[headcount].len;
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++headcount;
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seg += in;
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}
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heads[headcount - 1].len += datalen;
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*iovcount = seg;
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if (unlikely(log))
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*log_num = nlogs;
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return headcount;
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err:
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vhost_discard_vq_desc(vq, headcount);
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return r;
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}
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/* Expects to be always run from workqueue - which acts as
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* read-size critical section for our kind of RCU. */
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static void handle_rx(struct vhost_net *net)
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static void handle_rx_big(struct vhost_net *net)
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{
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struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
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unsigned out, in, log, s;
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@ -223,7 +312,7 @@ static void handle_rx(struct vhost_net *net)
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use_mm(net->dev.mm);
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mutex_lock(&vq->mutex);
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vhost_disable_notify(vq);
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hdr_size = vq->hdr_size;
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hdr_size = vq->vhost_hlen;
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vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ?
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vq->log : NULL;
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@ -270,14 +359,14 @@ static void handle_rx(struct vhost_net *net)
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len, MSG_DONTWAIT | MSG_TRUNC);
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/* TODO: Check specific error and bomb out unless EAGAIN? */
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if (err < 0) {
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vhost_discard_vq_desc(vq);
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vhost_discard_vq_desc(vq, 1);
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break;
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}
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/* TODO: Should check and handle checksum. */
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if (err > len) {
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pr_debug("Discarded truncated rx packet: "
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" len %d > %zd\n", err, len);
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vhost_discard_vq_desc(vq);
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vhost_discard_vq_desc(vq, 1);
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continue;
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}
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len = err;
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@ -302,54 +391,175 @@ static void handle_rx(struct vhost_net *net)
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unuse_mm(net->dev.mm);
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}
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static void handle_tx_kick(struct work_struct *work)
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/* Expects to be always run from workqueue - which acts as
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* read-size critical section for our kind of RCU. */
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static void handle_rx_mergeable(struct vhost_net *net)
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{
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struct vhost_virtqueue *vq;
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struct vhost_net *net;
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vq = container_of(work, struct vhost_virtqueue, poll.work);
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net = container_of(vq->dev, struct vhost_net, dev);
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struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
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unsigned uninitialized_var(in), log;
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struct vhost_log *vq_log;
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struct msghdr msg = {
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.msg_name = NULL,
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.msg_namelen = 0,
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.msg_control = NULL, /* FIXME: get and handle RX aux data. */
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.msg_controllen = 0,
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.msg_iov = vq->iov,
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.msg_flags = MSG_DONTWAIT,
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};
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struct virtio_net_hdr_mrg_rxbuf hdr = {
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.hdr.flags = 0,
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.hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE
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};
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size_t total_len = 0;
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int err, headcount;
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size_t vhost_hlen, sock_hlen;
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size_t vhost_len, sock_len;
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struct socket *sock = rcu_dereference(vq->private_data);
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if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue))
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return;
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use_mm(net->dev.mm);
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mutex_lock(&vq->mutex);
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vhost_disable_notify(vq);
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vhost_hlen = vq->vhost_hlen;
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sock_hlen = vq->sock_hlen;
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vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ?
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vq->log : NULL;
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while ((sock_len = peek_head_len(sock->sk))) {
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sock_len += sock_hlen;
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vhost_len = sock_len + vhost_hlen;
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headcount = get_rx_bufs(vq, vq->heads, vhost_len,
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&in, vq_log, &log);
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/* On error, stop handling until the next kick. */
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if (unlikely(headcount < 0))
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break;
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/* OK, now we need to know about added descriptors. */
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if (!headcount) {
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if (unlikely(vhost_enable_notify(vq))) {
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/* They have slipped one in as we were
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* doing that: check again. */
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vhost_disable_notify(vq);
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continue;
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}
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/* Nothing new? Wait for eventfd to tell us
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* they refilled. */
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break;
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}
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/* We don't need to be notified again. */
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if (unlikely((vhost_hlen)))
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/* Skip header. TODO: support TSO. */
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move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in);
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else
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/* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF:
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* needed because sendmsg can modify msg_iov. */
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copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in);
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msg.msg_iovlen = in;
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err = sock->ops->recvmsg(NULL, sock, &msg,
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sock_len, MSG_DONTWAIT | MSG_TRUNC);
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/* Userspace might have consumed the packet meanwhile:
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* it's not supposed to do this usually, but might be hard
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* to prevent. Discard data we got (if any) and keep going. */
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if (unlikely(err != sock_len)) {
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pr_debug("Discarded rx packet: "
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" len %d, expected %zd\n", err, sock_len);
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vhost_discard_vq_desc(vq, headcount);
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continue;
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}
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if (unlikely(vhost_hlen) &&
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memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0,
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vhost_hlen)) {
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vq_err(vq, "Unable to write vnet_hdr at addr %p\n",
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vq->iov->iov_base);
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break;
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}
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/* TODO: Should check and handle checksum. */
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if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF) &&
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memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount,
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offsetof(typeof(hdr), num_buffers),
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sizeof hdr.num_buffers)) {
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vq_err(vq, "Failed num_buffers write");
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vhost_discard_vq_desc(vq, headcount);
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break;
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}
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vhost_add_used_and_signal_n(&net->dev, vq, vq->heads,
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headcount);
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if (unlikely(vq_log))
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vhost_log_write(vq, vq_log, log, vhost_len);
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total_len += vhost_len;
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if (unlikely(total_len >= VHOST_NET_WEIGHT)) {
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vhost_poll_queue(&vq->poll);
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break;
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}
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}
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mutex_unlock(&vq->mutex);
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unuse_mm(net->dev.mm);
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}
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static void handle_rx(struct vhost_net *net)
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{
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if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF))
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handle_rx_mergeable(net);
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else
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handle_rx_big(net);
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}
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static void handle_tx_kick(struct vhost_work *work)
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{
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struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
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poll.work);
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struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev);
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handle_tx(net);
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}
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static void handle_rx_kick(struct work_struct *work)
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static void handle_rx_kick(struct vhost_work *work)
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{
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struct vhost_virtqueue *vq;
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struct vhost_net *net;
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vq = container_of(work, struct vhost_virtqueue, poll.work);
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net = container_of(vq->dev, struct vhost_net, dev);
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struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
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poll.work);
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struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev);
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handle_rx(net);
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}
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static void handle_tx_net(struct work_struct *work)
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static void handle_tx_net(struct vhost_work *work)
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{
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struct vhost_net *net;
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net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_TX].work);
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||||
struct vhost_net *net = container_of(work, struct vhost_net,
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poll[VHOST_NET_VQ_TX].work);
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handle_tx(net);
|
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}
|
||||
|
||||
static void handle_rx_net(struct work_struct *work)
|
||||
static void handle_rx_net(struct vhost_work *work)
|
||||
{
|
||||
struct vhost_net *net;
|
||||
net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_RX].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(&n->dev, n->vqs, VHOST_NET_VQ_MAX);
|
||||
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);
|
||||
vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN);
|
||||
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;
|
||||
@ -573,9 +783,21 @@ done:
|
||||
|
||||
static int vhost_net_set_features(struct vhost_net *n, u64 features)
|
||||
{
|
||||
size_t hdr_size = features & (1 << VHOST_NET_F_VIRTIO_NET_HDR) ?
|
||||
sizeof(struct virtio_net_hdr) : 0;
|
||||
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)) {
|
||||
@ -586,7 +808,8 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features)
|
||||
smp_wmb();
|
||||
for (i = 0; i < VHOST_NET_VQ_MAX; ++i) {
|
||||
mutex_lock(&n->vqs[i].mutex);
|
||||
n->vqs[i].hdr_size = hdr_size;
|
||||
n->vqs[i].vhost_hlen = vhost_hlen;
|
||||
n->vqs[i].sock_hlen = sock_hlen;
|
||||
mutex_unlock(&n->vqs[i].mutex);
|
||||
}
|
||||
vhost_net_flush(n);
|
||||
@ -656,25 +879,13 @@ static struct miscdevice vhost_net_misc = {
|
||||
|
||||
static int vhost_net_init(void)
|
||||
{
|
||||
int r = vhost_init();
|
||||
if (r)
|
||||
goto err_init;
|
||||
r = misc_register(&vhost_net_misc);
|
||||
if (r)
|
||||
goto err_reg;
|
||||
return 0;
|
||||
err_reg:
|
||||
vhost_cleanup();
|
||||
err_init:
|
||||
return r;
|
||||
|
||||
return misc_register(&vhost_net_misc);
|
||||
}
|
||||
module_init(vhost_net_init);
|
||||
|
||||
static void vhost_net_exit(void)
|
||||
{
|
||||
misc_deregister(&vhost_net_misc);
|
||||
vhost_cleanup();
|
||||
}
|
||||
module_exit(vhost_net_exit);
|
||||
|
||||
|
||||
@ -17,12 +17,13 @@
|
||||
#include <linux/mm.h>
|
||||
#include <linux/miscdevice.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/workqueue.h>
|
||||
#include <linux/rcupdate.h>
|
||||
#include <linux/poll.h>
|
||||
#include <linux/file.h>
|
||||
#include <linux/highmem.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/kthread.h>
|
||||
#include <linux/cgroup.h>
|
||||
|
||||
#include <linux/net.h>
|
||||
#include <linux/if_packet.h>
|
||||
@ -37,8 +38,6 @@ enum {
|
||||
VHOST_MEMORY_F_LOG = 0x1,
|
||||
};
|
||||
|
||||
static struct workqueue_struct *vhost_workqueue;
|
||||
|
||||
static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
|
||||
poll_table *pt)
|
||||
{
|
||||
@ -52,23 +51,31 @@ static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
|
||||
static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync,
|
||||
void *key)
|
||||
{
|
||||
struct vhost_poll *poll;
|
||||
poll = container_of(wait, struct vhost_poll, wait);
|
||||
struct vhost_poll *poll = container_of(wait, struct vhost_poll, wait);
|
||||
|
||||
if (!((unsigned long)key & poll->mask))
|
||||
return 0;
|
||||
|
||||
queue_work(vhost_workqueue, &poll->work);
|
||||
vhost_poll_queue(poll);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Init poll structure */
|
||||
void vhost_poll_init(struct vhost_poll *poll, work_func_t func,
|
||||
unsigned long mask)
|
||||
void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
|
||||
unsigned long mask, struct vhost_dev *dev)
|
||||
{
|
||||
INIT_WORK(&poll->work, func);
|
||||
struct vhost_work *work = &poll->work;
|
||||
|
||||
init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup);
|
||||
init_poll_funcptr(&poll->table, vhost_poll_func);
|
||||
poll->mask = mask;
|
||||
poll->dev = dev;
|
||||
|
||||
INIT_LIST_HEAD(&work->node);
|
||||
work->fn = fn;
|
||||
init_waitqueue_head(&work->done);
|
||||
work->flushing = 0;
|
||||
work->queue_seq = work->done_seq = 0;
|
||||
}
|
||||
|
||||
/* Start polling a file. We add ourselves to file's wait queue. The caller must
|
||||
@ -92,12 +99,40 @@ void vhost_poll_stop(struct vhost_poll *poll)
|
||||
* locks that are also used by the callback. */
|
||||
void vhost_poll_flush(struct vhost_poll *poll)
|
||||
{
|
||||
flush_work(&poll->work);
|
||||
struct vhost_work *work = &poll->work;
|
||||
unsigned seq;
|
||||
int left;
|
||||
int flushing;
|
||||
|
||||
spin_lock_irq(&poll->dev->work_lock);
|
||||
seq = work->queue_seq;
|
||||
work->flushing++;
|
||||
spin_unlock_irq(&poll->dev->work_lock);
|
||||
wait_event(work->done, ({
|
||||
spin_lock_irq(&poll->dev->work_lock);
|
||||
left = seq - work->done_seq <= 0;
|
||||
spin_unlock_irq(&poll->dev->work_lock);
|
||||
left;
|
||||
}));
|
||||
spin_lock_irq(&poll->dev->work_lock);
|
||||
flushing = --work->flushing;
|
||||
spin_unlock_irq(&poll->dev->work_lock);
|
||||
BUG_ON(flushing < 0);
|
||||
}
|
||||
|
||||
void vhost_poll_queue(struct vhost_poll *poll)
|
||||
{
|
||||
queue_work(vhost_workqueue, &poll->work);
|
||||
struct vhost_dev *dev = poll->dev;
|
||||
struct vhost_work *work = &poll->work;
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&dev->work_lock, flags);
|
||||
if (list_empty(&work->node)) {
|
||||
list_add_tail(&work->node, &dev->work_list);
|
||||
work->queue_seq++;
|
||||
wake_up_process(dev->worker);
|
||||
}
|
||||
spin_unlock_irqrestore(&dev->work_lock, flags);
|
||||
}
|
||||
|
||||
static void vhost_vq_reset(struct vhost_dev *dev,
|
||||
@ -114,7 +149,8 @@ static void vhost_vq_reset(struct vhost_dev *dev,
|
||||
vq->used_flags = 0;
|
||||
vq->log_used = false;
|
||||
vq->log_addr = -1ull;
|
||||
vq->hdr_size = 0;
|
||||
vq->vhost_hlen = 0;
|
||||
vq->sock_hlen = 0;
|
||||
vq->private_data = NULL;
|
||||
vq->log_base = NULL;
|
||||
vq->error_ctx = NULL;
|
||||
@ -125,10 +161,51 @@ static void vhost_vq_reset(struct vhost_dev *dev,
|
||||
vq->log_ctx = NULL;
|
||||
}
|
||||
|
||||
static int vhost_worker(void *data)
|
||||
{
|
||||
struct vhost_dev *dev = data;
|
||||
struct vhost_work *work = NULL;
|
||||
unsigned uninitialized_var(seq);
|
||||
|
||||
for (;;) {
|
||||
/* mb paired w/ kthread_stop */
|
||||
set_current_state(TASK_INTERRUPTIBLE);
|
||||
|
||||
spin_lock_irq(&dev->work_lock);
|
||||
if (work) {
|
||||
work->done_seq = seq;
|
||||
if (work->flushing)
|
||||
wake_up_all(&work->done);
|
||||
}
|
||||
|
||||
if (kthread_should_stop()) {
|
||||
spin_unlock_irq(&dev->work_lock);
|
||||
__set_current_state(TASK_RUNNING);
|
||||
return 0;
|
||||
}
|
||||
if (!list_empty(&dev->work_list)) {
|
||||
work = list_first_entry(&dev->work_list,
|
||||
struct vhost_work, node);
|
||||
list_del_init(&work->node);
|
||||
seq = work->queue_seq;
|
||||
} else
|
||||
work = NULL;
|
||||
spin_unlock_irq(&dev->work_lock);
|
||||
|
||||
if (work) {
|
||||
__set_current_state(TASK_RUNNING);
|
||||
work->fn(work);
|
||||
} else
|
||||
schedule();
|
||||
|
||||
}
|
||||
}
|
||||
|
||||
long vhost_dev_init(struct vhost_dev *dev,
|
||||
struct vhost_virtqueue *vqs, int nvqs)
|
||||
{
|
||||
int i;
|
||||
|
||||
dev->vqs = vqs;
|
||||
dev->nvqs = nvqs;
|
||||
mutex_init(&dev->mutex);
|
||||
@ -136,6 +213,9 @@ long vhost_dev_init(struct vhost_dev *dev,
|
||||
dev->log_file = NULL;
|
||||
dev->memory = NULL;
|
||||
dev->mm = NULL;
|
||||
spin_lock_init(&dev->work_lock);
|
||||
INIT_LIST_HEAD(&dev->work_list);
|
||||
dev->worker = NULL;
|
||||
|
||||
for (i = 0; i < dev->nvqs; ++i) {
|
||||
dev->vqs[i].dev = dev;
|
||||
@ -143,9 +223,9 @@ long vhost_dev_init(struct vhost_dev *dev,
|
||||
vhost_vq_reset(dev, dev->vqs + i);
|
||||
if (dev->vqs[i].handle_kick)
|
||||
vhost_poll_init(&dev->vqs[i].poll,
|
||||
dev->vqs[i].handle_kick,
|
||||
POLLIN);
|
||||
dev->vqs[i].handle_kick, POLLIN, dev);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -159,12 +239,36 @@ long vhost_dev_check_owner(struct vhost_dev *dev)
|
||||
/* Caller should have device mutex */
|
||||
static long vhost_dev_set_owner(struct vhost_dev *dev)
|
||||
{
|
||||
struct task_struct *worker;
|
||||
int err;
|
||||
/* Is there an owner already? */
|
||||
if (dev->mm)
|
||||
return -EBUSY;
|
||||
if (dev->mm) {
|
||||
err = -EBUSY;
|
||||
goto err_mm;
|
||||
}
|
||||
/* No owner, become one */
|
||||
dev->mm = get_task_mm(current);
|
||||
worker = kthread_create(vhost_worker, dev, "vhost-%d", current->pid);
|
||||
if (IS_ERR(worker)) {
|
||||
err = PTR_ERR(worker);
|
||||
goto err_worker;
|
||||
}
|
||||
|
||||
dev->worker = worker;
|
||||
err = cgroup_attach_task_current_cg(worker);
|
||||
if (err)
|
||||
goto err_cgroup;
|
||||
wake_up_process(worker); /* avoid contributing to loadavg */
|
||||
|
||||
return 0;
|
||||
err_cgroup:
|
||||
kthread_stop(worker);
|
||||
err_worker:
|
||||
if (dev->mm)
|
||||
mmput(dev->mm);
|
||||
dev->mm = NULL;
|
||||
err_mm:
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Caller should have device mutex */
|
||||
@ -217,6 +321,9 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
|
||||
if (dev->mm)
|
||||
mmput(dev->mm);
|
||||
dev->mm = NULL;
|
||||
|
||||
WARN_ON(!list_empty(&dev->work_list));
|
||||
kthread_stop(dev->worker);
|
||||
}
|
||||
|
||||
static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz)
|
||||
@ -995,9 +1102,9 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
|
||||
}
|
||||
|
||||
/* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */
|
||||
void vhost_discard_vq_desc(struct vhost_virtqueue *vq)
|
||||
void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n)
|
||||
{
|
||||
vq->last_avail_idx--;
|
||||
vq->last_avail_idx -= n;
|
||||
}
|
||||
|
||||
/* After we've used one of their buffers, we tell them about it. We'll then
|
||||
@ -1042,6 +1149,67 @@ int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len)
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int __vhost_add_used_n(struct vhost_virtqueue *vq,
|
||||
struct vring_used_elem *heads,
|
||||
unsigned count)
|
||||
{
|
||||
struct vring_used_elem __user *used;
|
||||
int start;
|
||||
|
||||
start = vq->last_used_idx % vq->num;
|
||||
used = vq->used->ring + start;
|
||||
if (copy_to_user(used, heads, count * sizeof *used)) {
|
||||
vq_err(vq, "Failed to write used");
|
||||
return -EFAULT;
|
||||
}
|
||||
if (unlikely(vq->log_used)) {
|
||||
/* Make sure data is seen before log. */
|
||||
smp_wmb();
|
||||
/* Log used ring entry write. */
|
||||
log_write(vq->log_base,
|
||||
vq->log_addr +
|
||||
((void __user *)used - (void __user *)vq->used),
|
||||
count * sizeof *used);
|
||||
}
|
||||
vq->last_used_idx += count;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* After we've used one of their buffers, we tell them about it. We'll then
|
||||
* want to notify the guest, using eventfd. */
|
||||
int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
|
||||
unsigned count)
|
||||
{
|
||||
int start, n, r;
|
||||
|
||||
start = vq->last_used_idx % vq->num;
|
||||
n = vq->num - start;
|
||||
if (n < count) {
|
||||
r = __vhost_add_used_n(vq, heads, n);
|
||||
if (r < 0)
|
||||
return r;
|
||||
heads += n;
|
||||
count -= n;
|
||||
}
|
||||
r = __vhost_add_used_n(vq, heads, count);
|
||||
|
||||
/* Make sure buffer is written before we update index. */
|
||||
smp_wmb();
|
||||
if (put_user(vq->last_used_idx, &vq->used->idx)) {
|
||||
vq_err(vq, "Failed to increment used idx");
|
||||
return -EFAULT;
|
||||
}
|
||||
if (unlikely(vq->log_used)) {
|
||||
/* Log used index update. */
|
||||
log_write(vq->log_base,
|
||||
vq->log_addr + offsetof(struct vring_used, idx),
|
||||
sizeof vq->used->idx);
|
||||
if (vq->log_ctx)
|
||||
eventfd_signal(vq->log_ctx, 1);
|
||||
}
|
||||
return r;
|
||||
}
|
||||
|
||||
/* This actually signals the guest, using eventfd. */
|
||||
void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
|
||||
{
|
||||
@ -1076,6 +1244,15 @@ void vhost_add_used_and_signal(struct vhost_dev *dev,
|
||||
vhost_signal(dev, vq);
|
||||
}
|
||||
|
||||
/* multi-buffer version of vhost_add_used_and_signal */
|
||||
void vhost_add_used_and_signal_n(struct vhost_dev *dev,
|
||||
struct vhost_virtqueue *vq,
|
||||
struct vring_used_elem *heads, unsigned count)
|
||||
{
|
||||
vhost_add_used_n(vq, heads, count);
|
||||
vhost_signal(dev, vq);
|
||||
}
|
||||
|
||||
/* OK, now we need to know about added descriptors. */
|
||||
bool vhost_enable_notify(struct vhost_virtqueue *vq)
|
||||
{
|
||||
@ -1100,7 +1277,7 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq)
|
||||
return false;
|
||||
}
|
||||
|
||||
return avail_idx != vq->last_avail_idx;
|
||||
return avail_idx != vq->avail_idx;
|
||||
}
|
||||
|
||||
/* We don't need to be notified again. */
|
||||
@ -1115,16 +1292,3 @@ void vhost_disable_notify(struct vhost_virtqueue *vq)
|
||||
vq_err(vq, "Failed to enable notification at %p: %d\n",
|
||||
&vq->used->flags, r);
|
||||
}
|
||||
|
||||
int vhost_init(void)
|
||||
{
|
||||
vhost_workqueue = create_singlethread_workqueue("vhost");
|
||||
if (!vhost_workqueue)
|
||||
return -ENOMEM;
|
||||
return 0;
|
||||
}
|
||||
|
||||
void vhost_cleanup(void)
|
||||
{
|
||||
destroy_workqueue(vhost_workqueue);
|
||||
}
|
||||
|
||||
@ -5,13 +5,13 @@
|
||||
#include <linux/vhost.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/workqueue.h>
|
||||
#include <linux/poll.h>
|
||||
#include <linux/file.h>
|
||||
#include <linux/skbuff.h>
|
||||
#include <linux/uio.h>
|
||||
#include <linux/virtio_config.h>
|
||||
#include <linux/virtio_ring.h>
|
||||
#include <asm/atomic.h>
|
||||
|
||||
struct vhost_device;
|
||||
|
||||
@ -20,19 +20,31 @@ enum {
|
||||
VHOST_NET_MAX_SG = MAX_SKB_FRAGS + 2,
|
||||
};
|
||||
|
||||
struct vhost_work;
|
||||
typedef void (*vhost_work_fn_t)(struct vhost_work *work);
|
||||
|
||||
struct vhost_work {
|
||||
struct list_head node;
|
||||
vhost_work_fn_t fn;
|
||||
wait_queue_head_t done;
|
||||
int flushing;
|
||||
unsigned queue_seq;
|
||||
unsigned done_seq;
|
||||
};
|
||||
|
||||
/* Poll a file (eventfd or socket) */
|
||||
/* Note: there's nothing vhost specific about this structure. */
|
||||
struct vhost_poll {
|
||||
poll_table table;
|
||||
wait_queue_head_t *wqh;
|
||||
wait_queue_t wait;
|
||||
/* struct which will handle all actual work. */
|
||||
struct work_struct work;
|
||||
struct vhost_work work;
|
||||
unsigned long mask;
|
||||
struct vhost_dev *dev;
|
||||
};
|
||||
|
||||
void vhost_poll_init(struct vhost_poll *poll, work_func_t func,
|
||||
unsigned long mask);
|
||||
void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
|
||||
unsigned long mask, struct vhost_dev *dev);
|
||||
void vhost_poll_start(struct vhost_poll *poll, struct file *file);
|
||||
void vhost_poll_stop(struct vhost_poll *poll);
|
||||
void vhost_poll_flush(struct vhost_poll *poll);
|
||||
@ -63,7 +75,7 @@ struct vhost_virtqueue {
|
||||
struct vhost_poll poll;
|
||||
|
||||
/* The routine to call when the Guest pings us, or timeout. */
|
||||
work_func_t handle_kick;
|
||||
vhost_work_fn_t handle_kick;
|
||||
|
||||
/* Last available index we saw. */
|
||||
u16 last_avail_idx;
|
||||
@ -84,13 +96,15 @@ struct vhost_virtqueue {
|
||||
struct iovec indirect[VHOST_NET_MAX_SG];
|
||||
struct iovec iov[VHOST_NET_MAX_SG];
|
||||
struct iovec hdr[VHOST_NET_MAX_SG];
|
||||
size_t hdr_size;
|
||||
size_t vhost_hlen;
|
||||
size_t sock_hlen;
|
||||
struct vring_used_elem heads[VHOST_NET_MAX_SG];
|
||||
/* We use a kind of RCU to access private pointer.
|
||||
* All readers access it from workqueue, which makes it possible to
|
||||
* flush the workqueue instead of synchronize_rcu. Therefore readers do
|
||||
* All readers access it from worker, which makes it possible to
|
||||
* flush the vhost_work instead of synchronize_rcu. Therefore readers do
|
||||
* not need to call rcu_read_lock/rcu_read_unlock: the beginning of
|
||||
* work item execution acts instead of rcu_read_lock() and the end of
|
||||
* work item execution acts instead of rcu_read_lock().
|
||||
* vhost_work execution acts instead of rcu_read_lock() and the end of
|
||||
* vhost_work execution acts instead of rcu_read_lock().
|
||||
* Writers use virtqueue mutex. */
|
||||
void *private_data;
|
||||
/* Log write descriptors */
|
||||
@ -110,6 +124,9 @@ struct vhost_dev {
|
||||
int nvqs;
|
||||
struct file *log_file;
|
||||
struct eventfd_ctx *log_ctx;
|
||||
spinlock_t work_lock;
|
||||
struct list_head work_list;
|
||||
struct task_struct *worker;
|
||||
};
|
||||
|
||||
long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue *vqs, int nvqs);
|
||||
@ -124,21 +141,22 @@ int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
|
||||
struct iovec iov[], unsigned int iov_count,
|
||||
unsigned int *out_num, unsigned int *in_num,
|
||||
struct vhost_log *log, unsigned int *log_num);
|
||||
void vhost_discard_vq_desc(struct vhost_virtqueue *);
|
||||
void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
|
||||
|
||||
int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
|
||||
void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
|
||||
int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
|
||||
unsigned count);
|
||||
void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
|
||||
unsigned int head, int len);
|
||||
unsigned int id, int len);
|
||||
void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
|
||||
struct vring_used_elem *heads, unsigned count);
|
||||
void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
|
||||
void vhost_disable_notify(struct vhost_virtqueue *);
|
||||
bool vhost_enable_notify(struct vhost_virtqueue *);
|
||||
|
||||
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
|
||||
unsigned int log_num, u64 len);
|
||||
|
||||
int vhost_init(void);
|
||||
void vhost_cleanup(void);
|
||||
|
||||
#define vq_err(vq, fmt, ...) do { \
|
||||
pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
|
||||
if ((vq)->error_ctx) \
|
||||
@ -149,7 +167,8 @@ enum {
|
||||
VHOST_FEATURES = (1 << VIRTIO_F_NOTIFY_ON_EMPTY) |
|
||||
(1 << VIRTIO_RING_F_INDIRECT_DESC) |
|
||||
(1 << VHOST_F_LOG_ALL) |
|
||||
(1 << VHOST_NET_F_VIRTIO_NET_HDR),
|
||||
(1 << VHOST_NET_F_VIRTIO_NET_HDR) |
|
||||
(1 << VIRTIO_NET_F_MRG_RXBUF),
|
||||
};
|
||||
|
||||
static inline int vhost_has_feature(struct vhost_dev *dev, int bit)
|
||||
|
||||
@ -570,6 +570,7 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp,
|
||||
void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it);
|
||||
int cgroup_scan_tasks(struct cgroup_scanner *scan);
|
||||
int cgroup_attach_task(struct cgroup *, struct task_struct *);
|
||||
int cgroup_attach_task_current_cg(struct task_struct *);
|
||||
|
||||
/*
|
||||
* CSS ID is ID for cgroup_subsys_state structs under subsys. This only works
|
||||
@ -626,6 +627,12 @@ static inline int cgroupstats_build(struct cgroupstats *stats,
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* No cgroups - nothing to do */
|
||||
static inline int cgroup_attach_task_current_cg(struct task_struct *t)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
|
||||
#endif /* !CONFIG_CGROUPS */
|
||||
|
||||
#endif /* _LINUX_CGROUP_H */
|
||||
|
||||
@ -1788,6 +1788,29 @@ out:
|
||||
return retval;
|
||||
}
|
||||
|
||||
/**
|
||||
* cgroup_attach_task_current_cg - attach task 'tsk' to current task's cgroup
|
||||
* @tsk: the task to be attached
|
||||
*/
|
||||
int cgroup_attach_task_current_cg(struct task_struct *tsk)
|
||||
{
|
||||
struct cgroupfs_root *root;
|
||||
struct cgroup *cur_cg;
|
||||
int retval = 0;
|
||||
|
||||
cgroup_lock();
|
||||
for_each_active_root(root) {
|
||||
cur_cg = task_cgroup_from_root(current, root);
|
||||
retval = cgroup_attach_task(cur_cg, tsk);
|
||||
if (retval)
|
||||
break;
|
||||
}
|
||||
cgroup_unlock();
|
||||
|
||||
return retval;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(cgroup_attach_task_current_cg);
|
||||
|
||||
/*
|
||||
* Attach task with pid 'pid' to cgroup 'cgrp'. Call with cgroup_mutex
|
||||
* held. May take task_lock of task
|
||||
|
||||
Loading…
Reference in New Issue
Block a user