Re: [Qemu-devel] [PATCH v3 08/16] vhost-user: send log shm fd along with log_base

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Aug 06, 2015 at 02:40:44PM +0200, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> Send the shm for the dirty pages logging if the backend support

supports

> VHOST_USER_PROTOCOL_F_LOG_SHMFD.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  hw/virtio/vhost-user.c | 16 ++++++++++++++--
>  hw/virtio/vhost.c      |  5 +++--
>  2 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index 21ecbcd..b2f46a9 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -26,7 +26,9 @@
>  #define VHOST_MEMORY_MAX_NREGIONS    8
>  
>  #define VHOST_USER_F_PROTOCOL_FEATURES 30
> -#define VHOST_USER_PROTOCOL_FEATURE_MASK 0x0ULL
> +
> +#define VHOST_USER_PROTOCOL_FEATURE_MASK 0x1ULL
> +#define VHOST_USER_PROTOCOL_F_LOG_SHMFD 0
>  
>  typedef enum VhostUserRequest {
>      VHOST_USER_NONE = 0,
> @@ -215,8 +217,18 @@ static int vhost_user_call(struct vhost_dev *dev,
>          need_reply = 1;
>          break;
>  
> +    case VHOST_USER_SET_LOG_BASE: {
> +        struct vhost_log *log = va_arg(ap, struct vhost_log *);
> +
> +        if (__virtio_has_feature(dev->protocol_features,
> +                                 VHOST_USER_PROTOCOL_F_LOG_SHMFD) &&
> +            log->fd != -1) {
> +            fds[fd_num++] = log->fd;
> +        }
> +    }
> +        /* fall through */
> +

Don't add {} like that please. Just move declarations to the top level.


>      case VHOST_USER_SET_FEATURES:
> -    case VHOST_USER_SET_LOG_BASE:
>          msg.u64 = *((__u64 *) arg);
>          msg.size = sizeof(m.u64);
>          break;
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 057d548..ed8b1a5 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -359,7 +359,7 @@ static inline void vhost_dev_log_resize(struct vhost_dev* dev, uint64_t size)
>  
>      /* inform backend of log switching, this must be done before
>         releasing the current log, to ensure no logging is lost */
> -    r = dev->vhost_ops->vhost_call(dev, VHOST_SET_LOG_BASE, &log_base);
> +    r = dev->vhost_ops->vhost_call(dev, VHOST_SET_LOG_BASE, &log_base, log);
>      assert(r >= 0);
>      vhost_log_put(dev, true);
>      dev->log = log;
> @@ -1167,7 +1167,8 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev)
>          hdev->log = vhost_log_get(hdev->log_size, share);
>          log_base = (uintptr_t)hdev->log->log;
>          r = hdev->vhost_ops->vhost_call(hdev, VHOST_SET_LOG_BASE,
> -                                        hdev->log_size ? &log_base : NULL);
> +                                        hdev->log_size ? &log_base : NULL,
> +                                        hdev->log);
>          if (r < 0) {
>              r = -errno;
>              goto fail_log;
> -- 
> 2.4.3