2 files changed, 64 insertions, 150 deletions

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index f616cefc95ba..2f7c76a85e53 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -60,6 +60,7 @@ static int move_iovec_hdr(struct iovec *from, struct iovec *to,
 {
         int seg = 0;
         size_t size;
+
         while (len && seg < iov_count) {
                 size = min(from->iov_len, len);
                 to->iov_base = from->iov_base;
@@ -79,6 +80,7 @@ static void copy_iovec_hdr(const struct iovec *from, struct iovec *to,
 {
         int seg = 0;
         size_t size;
+
         while (len && seg < iovcount) {
                 size = min(from->iov_len, len);
                 to->iov_base = from->iov_base;
@@ -211,12 +213,13 @@ static int peek_head_len(struct sock *sk)
 {
         struct sk_buff *head;
         int len = 0;
+        unsigned long flags;
 
-        lock_sock(sk);
+        spin_lock_irqsave(&sk->sk_receive_queue.lock, flags);
         head = skb_peek(&sk->sk_receive_queue);
-        if (head)
+        if (likely(head))
                 len = head->len;
-        release_sock(sk);
+        spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags);
         return len;
 }
 
@@ -227,6 +230,7 @@ static int peek_head_len(struct sock *sk)
  * @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,
@@ -234,7 +238,8 @@ static int get_rx_bufs(struct vhost_virtqueue *vq,
                        int datalen,
                        unsigned *iovcount,
                        struct vhost_log *log,
-                       unsigned *log_num)
+                       unsigned *log_num,
+                       unsigned int quota)
 {
         unsigned int out, in;
         int seg = 0;
@@ -242,7 +247,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq,
         unsigned d;
         int r, nlogs = 0;
 
-        while (datalen > 0) {
+        while (datalen > 0 && headcount < quota) {
                 if (unlikely(seg >= UIO_MAXIOV)) {
                         r = -ENOBUFS;
                         goto err;
@@ -282,117 +287,7 @@ err:
 
 /* Expects to be always run from workqueue - which acts as
  * read-size critical section for our kind of RCU. */
-static void handle_rx_big(struct vhost_net *net)
-{
-        struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
-        unsigned out, in, log, s;
-        int head;
-        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 hdr = {
-                .flags = 0,
-                .gso_type = VIRTIO_NET_HDR_GSO_NONE
-        };
-
-        size_t len, total_len = 0;
-        int err;
-        size_t hdr_size;
-        /* TODO: check that we are running from vhost_worker? */
-        struct socket *sock = rcu_dereference_check(vq->private_data, 1);
-        if (!sock || skb_queue_empty(&sock->sk->sk_receive_queue))
-                return;
-
-        mutex_lock(&vq->mutex);
-        vhost_disable_notify(vq);
-        hdr_size = vq->vhost_hlen;
-
-        vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ?
-                vq->log : NULL;
-
-        for (;;) {
-                head = vhost_get_vq_desc(&net->dev, vq, vq->iov,
-                                         ARRAY_SIZE(vq->iov),
-                                         &out, &in,
-                                         vq_log, &log);
-                /* On error, stop handling until the next kick. */
-                if (unlikely(head < 0))
-                        break;
-                /* OK, now we need to know about added descriptors. */
-                if (head == vq->num) {
-                        if (unlikely(vhost_enable_notify(vq))) {
-                                /* They have slipped one in as we were
-                                 * doing that: check again. */
-                                vhost_disable_notify(vq);
-                                continue;
-                        }
-                        /* Nothing new?  Wait for eventfd to tell us
-                         * they refilled. */
-                        break;
-                }
-                /* We don't need to be notified again. */
-                if (out) {
-                        vq_err(vq, "Unexpected descriptor format for RX: "
-                               "out %d, int %d\n",
-                               out, in);
-                        break;
-                }
-                /* Skip header. TODO: support TSO/mergeable rx buffers. */
-                s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, in);
-                msg.msg_iovlen = in;
-                len = iov_length(vq->iov, in);
-                /* Sanity check */
-                if (!len) {
-                        vq_err(vq, "Unexpected header len for RX: "
-                               "%zd expected %zd\n",
-                               iov_length(vq->hdr, s), hdr_size);
-                        break;
-                }
-                err = sock->ops->recvmsg(NULL, sock, &msg,
-                                         len, MSG_DONTWAIT | MSG_TRUNC);
-                /* TODO: Check specific error and bomb out unless EAGAIN? */
-                if (err < 0) {
-                        vhost_discard_vq_desc(vq, 1);
-                        break;
-                }
-                /* TODO: Should check and handle checksum. */
-                if (err > len) {
-                        pr_debug("Discarded truncated rx packet: "
-                                 " len %d > %zd\n", err, len);
-                        vhost_discard_vq_desc(vq, 1);
-                        continue;
-                }
-                len = err;
-                err = memcpy_toiovec(vq->hdr, (unsigned char *)&hdr, hdr_size);
-                if (err) {
-                        vq_err(vq, "Unable to write vnet_hdr at addr %p: %d\n",
-                               vq->iov->iov_base, err);
-                        break;
-                }
-                len += hdr_size;
-                vhost_add_used_and_signal(&net->dev, vq, head, len);
-                if (unlikely(vq_log))
-                        vhost_log_write(vq, vq_log, log, len);
-                total_len += len;
-                if (unlikely(total_len >= VHOST_NET_WEIGHT)) {
-                        vhost_poll_queue(&vq->poll);
-                        break;
-                }
-        }
-
-        mutex_unlock(&vq->mutex);
-}
-
-/* Expects to be always run from workqueue - which acts as
- * read-size critical section for our kind of RCU. */
-static void handle_rx_mergeable(struct vhost_net *net)
+static void handle_rx(struct vhost_net *net)
 {
         struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
         unsigned uninitialized_var(in), log;
@@ -405,19 +300,18 @@ static void handle_rx_mergeable(struct vhost_net *net)
                 .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;
+        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 || skb_queue_empty(&sock->sk->sk_receive_queue))
+
+        if (!sock)
                 return;
 
         mutex_lock(&vq->mutex);
@@ -427,12 +321,14 @@ static void handle_rx_mergeable(struct vhost_net *net)
 
         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);
+                                        &in, vq_log, &log,
+                                        likely(mergeable) ? UIO_MAXIOV : 1);
                 /* On error, stop handling until the next kick. */
                 if (unlikely(headcount < 0))
                         break;
@@ -476,7 +372,7 @@ static void handle_rx_mergeable(struct vhost_net *net)
                         break;
                 }
                 /* TODO: Should check and handle checksum. */
-                if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF) &&
+                if (likely(mergeable) &&
                     memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount,
                                       offsetof(typeof(hdr), num_buffers),
                                       sizeof hdr.num_buffers)) {
@@ -498,14 +394,6 @@ static void handle_rx_mergeable(struct vhost_net *net)
         mutex_unlock(&vq->mutex);
 }
 
-static void handle_rx(struct vhost_net *net)
-{
-        if (vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF))
-                handle_rx_mergeable(net);
-        else
-                handle_rx_big(net);
-}
-
 static void handle_tx_kick(struct vhost_work *work)
 {
         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
@@ -654,6 +542,7 @@ static struct socket *get_raw_socket(int fd)
         } uaddr;
         int uaddr_len = sizeof uaddr, r;
         struct socket *sock = sockfd_lookup(fd, &r);
+
         if (!sock)
                 return ERR_PTR(-ENOTSOCK);
 
@@ -682,6 +571,7 @@ 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);
@@ -696,6 +586,7 @@ static struct socket *get_tap_socket(int fd)
 static struct socket *get_socket(int fd)
 {
         struct socket *sock;
+
         /* special case to disable backend */
         if (fd == -1)
                 return NULL;
@@ -741,9 +632,9 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
         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);
+                vhost_net_disable_vq(n, vq);
+                rcu_assign_pointer(vq->private_data, sock);
+                vhost_net_enable_vq(n, vq);
         }
 
         mutex_unlock(&vq->mutex);
@@ -768,6 +659,7 @@ 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)
@@ -829,6 +721,7 @@ static long vhost_net_ioctl(struct file *f, unsigned int ioctl,
         struct vhost_vring_file backend;
         u64 features;
         int r;
+
         switch (ioctl) {
         case VHOST_NET_SET_BACKEND:
                 if (copy_from_user(&backend, argp, sizeof backend))
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index ade0568c07a4..2ab291241635 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -41,8 +41,8 @@ static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
                             poll_table *pt)
 {
         struct vhost_poll *poll;
-        poll = container_of(pt, struct vhost_poll, table);
 
+        poll = container_of(pt, struct vhost_poll, table);
         poll->wqh = wqh;
         add_wait_queue(wqh, &poll->wait);
 }
@@ -85,6 +85,7 @@ void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
 void vhost_poll_start(struct vhost_poll *poll, struct file *file)
 {
         unsigned long mask;
+
         mask = file->f_op->poll(file, &poll->table);
         if (mask)
                 vhost_poll_wakeup(&poll->wait, 0, 0, (void *)mask);
@@ -101,6 +102,7 @@ static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work,
                                 unsigned seq)
 {
         int left;
+
         spin_lock_irq(&dev->work_lock);
         left = seq - work->done_seq;
         spin_unlock_irq(&dev->work_lock);
@@ -222,6 +224,7 @@ static int vhost_worker(void *data)
 static long vhost_dev_alloc_iovecs(struct vhost_dev *dev)
 {
         int i;
+
         for (i = 0; i < dev->nvqs; ++i) {
                 dev->vqs[i].indirect = kmalloc(sizeof *dev->vqs[i].indirect *
                                                UIO_MAXIOV, GFP_KERNEL);
@@ -235,6 +238,7 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev)
                         goto err_nomem;
         }
         return 0;
+
 err_nomem:
         for (; i >= 0; --i) {
                 kfree(dev->vqs[i].indirect);
@@ -247,6 +251,7 @@ err_nomem:
 static void vhost_dev_free_iovecs(struct vhost_dev *dev)
 {
         int i;
+
         for (i = 0; i < dev->nvqs; ++i) {
                 kfree(dev->vqs[i].indirect);
                 dev->vqs[i].indirect = NULL;
@@ -296,26 +301,28 @@ long vhost_dev_check_owner(struct vhost_dev *dev)
 }
 
 struct vhost_attach_cgroups_struct {
-        struct vhost_work work;
-        struct task_struct *owner;
-        int ret;
+        struct vhost_work work;
+        struct task_struct *owner;
+        int ret;
 };
 
 static void vhost_attach_cgroups_work(struct vhost_work *work)
 {
-        struct vhost_attach_cgroups_struct *s;
-        s = container_of(work, struct vhost_attach_cgroups_struct, work);
-        s->ret = cgroup_attach_task_all(s->owner, current);
+        struct vhost_attach_cgroups_struct *s;
+
+        s = container_of(work, struct vhost_attach_cgroups_struct, work);
+        s->ret = cgroup_attach_task_all(s->owner, current);
 }
 
 static int vhost_attach_cgroups(struct vhost_dev *dev)
 {
-        struct vhost_attach_cgroups_struct attach;
-        attach.owner = current;
-        vhost_work_init(&attach.work, vhost_attach_cgroups_work);
-        vhost_work_queue(dev, &attach.work);
-        vhost_work_flush(dev, &attach.work);
-        return attach.ret;
+        struct vhost_attach_cgroups_struct attach;
+
+        attach.owner = current;
+        vhost_work_init(&attach.work, vhost_attach_cgroups_work);
+        vhost_work_queue(dev, &attach.work);
+        vhost_work_flush(dev, &attach.work);
+        return attach.ret;
 }
 
 /* Caller should have device mutex */
@@ -323,11 +330,13 @@ static long vhost_dev_set_owner(struct vhost_dev *dev)
 {
         struct task_struct *worker;
         int err;
+
         /* Is there an owner already? */
         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);
@@ -380,6 +389,7 @@ long vhost_dev_reset_owner(struct vhost_dev *dev)
 void vhost_dev_cleanup(struct vhost_dev *dev)
 {
         int i;
+
         for (i = 0; i < dev->nvqs; ++i) {
                 if (dev->vqs[i].kick && dev->vqs[i].handle_kick) {
                         vhost_poll_stop(&dev->vqs[i].poll);
@@ -421,6 +431,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
 static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz)
 {
         u64 a = addr / VHOST_PAGE_SIZE / 8;
+
         /* Make sure 64 bit math will not overflow. */
         if (a > ULONG_MAX - (unsigned long)log_base ||
             a + (unsigned long)log_base > ULONG_MAX)
@@ -461,6 +472,7 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem,
                             int log_all)
 {
         int i;
+
         for (i = 0; i < d->nvqs; ++i) {
                 int ok;
                 mutex_lock(&d->vqs[i].mutex);
@@ -527,6 +539,7 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
 {
         struct vhost_memory mem, *newmem, *oldmem;
         unsigned long size = offsetof(struct vhost_memory, regions);
+
         if (copy_from_user(&mem, m, size))
                 return -EFAULT;
         if (mem.padding)
@@ -544,7 +557,8 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
                 return -EFAULT;
         }
 
-        if (!memory_access_ok(d, newmem, vhost_has_feature(d, VHOST_F_LOG_ALL))) {
+        if (!memory_access_ok(d, newmem,
+                              vhost_has_feature(d, VHOST_F_LOG_ALL))) {
                 kfree(newmem);
                 return -EFAULT;
         }
@@ -560,6 +574,7 @@ static int init_used(struct vhost_virtqueue *vq,
                      struct vring_used __user *used)
 {
         int r = put_user(vq->used_flags, &used->flags);
+
         if (r)
                 return r;
         return get_user(vq->last_used_idx, &used->idx);
@@ -849,6 +864,7 @@ static const struct vhost_memory_region *find_region(struct vhost_memory *mem,
 {
         struct vhost_memory_region *reg;
         int i;
+
         /* linear search is not brilliant, but we really have on the order of 6
          * regions in practice */
         for (i = 0; i < mem->nregions; ++i) {
@@ -871,6 +887,7 @@ static int set_bit_to_user(int nr, void __user *addr)
         void *base;
         int bit = nr + (log % PAGE_SIZE) * 8;
         int r;
+
         r = get_user_pages_fast(log, 1, 1, &page);
         if (r < 0)
                 return r;
@@ -888,6 +905,7 @@ static int log_write(void __user *log_base,
 {
         u64 write_page = write_address / VHOST_PAGE_SIZE;
         int r;
+
         if (!write_length)
                 return 0;
         write_length += write_address % VHOST_PAGE_SIZE;
@@ -1037,8 +1055,8 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
                                i, count);
                         return -EINVAL;
                 }
-                if (unlikely(memcpy_fromiovec((unsigned char *)&desc, vq->indirect,
-                                              sizeof desc))) {
+                if (unlikely(memcpy_fromiovec((unsigned char *)&desc,
+                                              vq->indirect, sizeof desc))) {
                         vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n",
                                i, (size_t)indirect->addr + i * sizeof desc);
                         return -EINVAL;
@@ -1153,7 +1171,7 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
                                i, vq->num, head);
                         return -EINVAL;
                 }
-                ret = copy_from_user(&desc, vq->desc + i, sizeof desc);
+                ret = __copy_from_user(&desc, vq->desc + i, sizeof desc);
                 if (unlikely(ret)) {
                         vq_err(vq, "Failed to get descriptor: idx %d addr %p\n",
                                i, vq->desc + i);
@@ -1317,6 +1335,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
 void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
 {
         __u16 flags;
+
         /* Flush out used index updates. This is paired
          * with the barrier that the Guest executes when enabling
          * interrupts. */
@@ -1361,6 +1380,7 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq)
 {
         u16 avail_idx;
         int r;
+
         if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY))
                 return false;
         vq->used_flags &= ~VRING_USED_F_NO_NOTIFY;
@@ -1387,6 +1407,7 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq)
 void vhost_disable_notify(struct vhost_virtqueue *vq)
 {
         int r;
+
         if (vq->used_flags & VRING_USED_F_NO_NOTIFY)
                 return;
         vq->used_flags |= VRING_USED_F_NO_NOTIFY;