Re: [PATCH v10 07/10] memory: Add interface to set iommu page size mask

[Auger Eric]

Hi Jean,

On 10/8/20 7:15 PM, Jean-Philippe Brucker wrote:
> From: Bharat Bhushan <bbhushan2@marvell.com>
> 
> Allow to set the page size mask supported by an iommu memory region.
> This enables a vIOMMU to communicate the page size granule supported by
> an assigned device, on hosts that use page sizes greater than 4kB.
> 
> Signed-off-by: Bharat Bhushan <bbhushan2@marvell.com>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
> v10: Add errp parameter
> ---
>  include/exec/memory.h | 26 ++++++++++++++++++++++++++
>  softmmu/memory.c      | 13 +++++++++++++
>  2 files changed, 39 insertions(+)
> 
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index dee09851622..c2da8381bec 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -382,6 +382,20 @@ struct IOMMUMemoryRegionClass {
>       * @iommu: the IOMMUMemoryRegion
>       */
>      int (*num_indexes)(IOMMUMemoryRegion *iommu);
> +
> +    /*
> +     * Set supported IOMMU page size
> +     *
> +     * If supported, allows to restrict the page size mask that can be 
> supported
To match other docs: Optional method:
> +     * with a given IOMMU memory region. For example, to propagate host 
> physical
> +     * IOMMU page size mask limitations to the virtual IOMMU.
> +     *
> +     * Returns 0 on success, or a negative error. In case of failure, the 
> error
> +     * object must be created.
document args as done for other functions?
> +     */
> +     int (*iommu_set_page_size_mask)(IOMMUMemoryRegion *iommu,
> +                                     uint64_t page_size_mask,
> +                                     Error **errp);
>  };
>  
>  typedef struct CoalescedMemoryRange CoalescedMemoryRange;
> @@ -1389,6 +1403,18 @@ int 
> memory_region_iommu_attrs_to_index(IOMMUMemoryRegion *iommu_mr,
>   */
>  int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr);
>  
> +/**
> + * memory_region_iommu_set_page_size_mask: set the supported page
> + * sizes for a given IOMMU memory region
> + *
> + * @iommu_mr: IOMMU memory region
> + * @page_size_mask: supported page size mask
> + * @errp: pointer to Error*, to store an error if it happens.
> + */
> +int memory_region_iommu_set_page_size_mask(IOMMUMemoryRegion *iommu_mr,
> +                                           uint64_t page_size_mask,
> +                                           Error **errp);
> +
>  /**
>   * memory_region_name: get a memory region's name
>   *
> diff --git a/softmmu/memory.c b/softmmu/memory.c
> index fa280a19f7f..5c855a02704 100644
> --- a/softmmu/memory.c
> +++ b/softmmu/memory.c
> @@ -1811,6 +1811,19 @@ static int 
> memory_region_update_iommu_notify_flags(IOMMUMemoryRegion *iommu_mr,
>      return ret;
>  }
>  
> +int memory_region_iommu_set_page_size_mask(IOMMUMemoryRegion *iommu_mr,
> +                                           uint64_t page_size_mask,
> +                                           Error **errp)
> +{
> +    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_GET_CLASS(iommu_mr);
> +    int ret = 0;
> +
> +    if (imrc->iommu_set_page_size_mask) {
> +        ret = imrc->iommu_set_page_size_mask(iommu_mr, page_size_mask, errp);
> +    }
> +    return ret;
> +}
> +
>  int memory_region_register_iommu_notifier(MemoryRegion *mr,
>                                            IOMMUNotifier *n, Error **errp)
>  {
> 
Besides

Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric