Re: [dpdk-dev] [PATCH dpdk 4/5] vfio: Do try setting IOMMU type if already set

[gowrishankar muthukrishnan <gowrishankar.m@linux.vnet.ibm.com>]

On Thursday 20 April 2017 12:54 PM, Alexey Kardashevskiy wrote:
> The existing code correctly checks if a container is set to a group and
> does not try attaching a group to a container for a second/third/...
> device from the same IOMMU group.
>
> However it still tries to set IOMMU type to a container for every device
> in a group which produces failure and closes container and group fds.
>
> This moves vfio_set_iommu_type() and DMA mapping code under:
> if (!(group_status.flags & VFIO_GROUP_FLAGS_CONTAINER_SET))
>
> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>

Thanks, verified it for regression seen on current master for mentioned 
scenario.

Regards,
Gowrishankar

> ---
>   lib/librte_eal/linuxapp/eal/eal_vfio.c | 50 +++++++++++++++++-----------------
>   1 file changed, 25 insertions(+), 25 deletions(-)
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c
> index 6e2e84ca7..46f951f4d 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
> @@ -298,33 +298,33 @@ vfio_setup_device(const char *sysfs_base, const char *dev_addr,
>   			clear_group(vfio_group_fd);
>   			return -1;
>   		}
> -	}
>
> -	/*
> -	 * pick an IOMMU type and set up DMA mappings for container
> -	 *
> -	 * needs to be done only once, only when first group is assigned to
> -	 * a container and only in primary process. Note this can happen several
> -	 * times with the hotplug functionality.
> -	 */
> -	if (internal_config.process_type == RTE_PROC_PRIMARY &&
> -			vfio_cfg.vfio_active_groups == 1) {
> -		/* select an IOMMU type which we will be using */
> -		const struct vfio_iommu_type *t =
> +		/*
> +		 * pick an IOMMU type and set up DMA mappings for container
> +		 *
> +		 * needs to be done only once, only when first group is assigned to
> +		 * a container and only in primary process. Note this can happen several
> +		 * times with the hotplug functionality.
> +		 */
> +		if (internal_config.process_type == RTE_PROC_PRIMARY &&
> +				vfio_cfg.vfio_active_groups == 1) {
> +			/* select an IOMMU type which we will be using */
> +			const struct vfio_iommu_type *t =
>   				vfio_set_iommu_type(vfio_cfg.vfio_container_fd);
> -		if (!t) {
> -			RTE_LOG(ERR, EAL, "  %s failed to select IOMMU type\n", dev_addr);
> -			close(vfio_group_fd);
> -			clear_group(vfio_group_fd);
> -			return -1;
> -		}
> -		ret = t->dma_map_func(vfio_cfg.vfio_container_fd);
> -		if (ret) {
> -			RTE_LOG(ERR, EAL, "  %s DMA remapping failed, "
> -					"error %i (%s)\n", dev_addr, errno, strerror(errno));
> -			close(vfio_group_fd);
> -			clear_group(vfio_group_fd);
> -			return -1;
> +			if (!t) {
> +				RTE_LOG(ERR, EAL, "  %s failed to select IOMMU type\n", dev_addr);
> +				close(vfio_group_fd);
> +				clear_group(vfio_group_fd);
> +				return -1;
> +			}
> +			ret = t->dma_map_func(vfio_cfg.vfio_container_fd);
> +			if (ret) {
> +				RTE_LOG(ERR, EAL, "  %s DMA remapping failed, "
> +						"error %i (%s)\n", dev_addr, errno, strerror(errno));
> +				close(vfio_group_fd);
> +				clear_group(vfio_group_fd);
> +				return -1;
> +			}
>   		}
>   	}
>