diff options
| -rw-r--r-- | drivers/vhost/vhost.c | 84 |
1 files changed, 54 insertions, 30 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 9a108038fe52..46822c0d9f7f 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -629,19 +629,6 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) return 0; } -int vhost_init_used(struct vhost_virtqueue *vq) -{ - int r; - if (!vq->private_data) - return 0; - - r = put_user(vq->used_flags, &vq->used->flags); - if (r) - return r; - vq->signalled_used_valid = false; - return get_user(vq->last_used_idx, &vq->used->idx); -} - static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) { struct file *eventfp, *filep = NULL, @@ -1008,6 +995,57 @@ int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, return 0; } +static int vhost_update_used_flags(struct vhost_virtqueue *vq) +{ + void __user *used; + if (put_user(vq->used_flags, &vq->used->flags) < 0) + return -EFAULT; + if (unlikely(vq->log_used)) { + /* Make sure the flag is seen before log. */ + smp_wmb(); + /* Log used flag write. */ + used = &vq->used->flags; + log_write(vq->log_base, vq->log_addr + + (used - (void __user *)vq->used), + sizeof vq->used->flags); + if (vq->log_ctx) + eventfd_signal(vq->log_ctx, 1); + } + return 0; +} + +static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) +{ + if (put_user(vq->avail_idx, vhost_avail_event(vq))) + return -EFAULT; + if (unlikely(vq->log_used)) { + void __user *used; + /* Make sure the event is seen before log. */ + smp_wmb(); + /* Log avail event write */ + used = vhost_avail_event(vq); + log_write(vq->log_base, vq->log_addr + + (used - (void __user *)vq->used), + sizeof *vhost_avail_event(vq)); + if (vq->log_ctx) + eventfd_signal(vq->log_ctx, 1); + } + return 0; +} + +int vhost_init_used(struct vhost_virtqueue *vq) +{ + int r; + if (!vq->private_data) + return 0; + + r = vhost_update_used_flags(vq); + if (r) + return r; + vq->signalled_used_valid = false; + return get_user(vq->last_used_idx, &vq->used->idx); +} + static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len, struct iovec iov[], int iov_size) { @@ -1479,34 +1517,20 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) return false; vq->used_flags &= ~VRING_USED_F_NO_NOTIFY; if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { - r = put_user(vq->used_flags, &vq->used->flags); + r = vhost_update_used_flags(vq); if (r) { vq_err(vq, "Failed to enable notification at %p: %d\n", &vq->used->flags, r); return false; } } else { - r = put_user(vq->avail_idx, vhost_avail_event(vq)); + r = vhost_update_avail_event(vq, vq->avail_idx); if (r) { vq_err(vq, "Failed to update avail event index at %p: %d\n", vhost_avail_event(vq), r); return false; } } - if (unlikely(vq->log_used)) { - void __user *used; - /* Make sure data is seen before log. */ - smp_wmb(); - used = vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX) ? - &vq->used->flags : vhost_avail_event(vq); - /* Log used flags or event index entry write. Both are 16 bit - * fields. */ - log_write(vq->log_base, vq->log_addr + - (used - (void __user *)vq->used), - sizeof(u16)); - if (vq->log_ctx) - eventfd_signal(vq->log_ctx, 1); - } /* They could have slipped one in as we were doing that: make * sure it's written, then check again. */ smp_mb(); @@ -1529,7 +1553,7 @@ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) return; vq->used_flags |= VRING_USED_F_NO_NOTIFY; if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { - r = put_user(vq->used_flags, &vq->used->flags); + r = vhost_update_used_flags(vq); if (r) vq_err(vq, "Failed to enable notification at %p: %d\n", &vq->used->flags, r); |