vhost: set log when updating used flags or avail event (2723feaa) · Commits · 戴 / test

drivers/vhost/vhost.c

+54 −30

Original line number	Diff line number	Diff line
		@@ -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);

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