Re: [PATCH 5/9] virtio-scsi: Implement TMF timeout

[Paolo Bonzini <pbonzini@redhat.com>]

Il 10/06/2013 03:40, Hannes Reinecke ha scritto:
> Any TMF might be take longer as expected, or not return at all.
> So we need to use 'wait_for_completion_timeout' when sending
> a TMF to protect against these cases.
> 
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Hannes Reinecke <hare@suse.de>
> ---
>  drivers/scsi/virtio_scsi.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
> index 1efd219..abfc684 100644
> --- a/drivers/scsi/virtio_scsi.c
> +++ b/drivers/scsi/virtio_scsi.c
> @@ -30,6 +30,7 @@
>  #define VIRTIO_SCSI_MEMPOOL_SZ 64
>  #define VIRTIO_SCSI_EVENT_LEN 8
>  #define VIRTIO_SCSI_VQ_BASE 2
> +#define VIRTIO_SCSI_TMF_TIMEOUT 30
>  
>  /* Command queue element */
>  struct virtio_scsi_cmd {
> @@ -597,8 +598,10 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
>  			      GFP_NOIO) < 0)
>  		goto out;
>  
> -	wait_for_completion(&comp);
> -	if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
> +	if (wait_for_completion_timeout(&comp,
> +					VIRTIO_SCSI_TMF_TIMEOUT * HZ) == 0)
> +		ret = FAILED;
> +	else if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
>  	    cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
>  		ret = SUCCESS;
>  
> 


Acked-by: Paolo Bonzini <pbonzini@redhat.com>