Re: [PATCH v7 03/12] iommu: Remove unrecoverable fault data

[Yi Liu <yi.l.liu@intel.com>]

On 2023/11/15 11:02, Lu Baolu wrote:
> The unrecoverable fault data is not used anywhere. Remove it to avoid
> dead code.
> 
> Suggested-by: Kevin Tian <kevin.tian@intel.com>
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
>   include/linux/iommu.h | 70 +------------------------------------------
>   1 file changed, 1 insertion(+), 69 deletions(-)
> 
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index c2e2225184cf..81eee1afec72 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -50,69 +50,9 @@ struct iommu_dma_cookie;
>   
>   /* Generic fault types, can be expanded IRQ remapping fault */
>   enum iommu_fault_type {
> -	IOMMU_FAULT_DMA_UNRECOV = 1,	/* unrecoverable fault */
>   	IOMMU_FAULT_PAGE_REQ,		/* page request fault */

a nit, do you kno why this enum was starting from 1? Should it still
start from 1 after deleting UNRECOV?

>   };
>   
> -enum iommu_fault_reason {
> -	IOMMU_FAULT_REASON_UNKNOWN = 0,
> -
> -	/* Could not access the PASID table (fetch caused external abort) */
> -	IOMMU_FAULT_REASON_PASID_FETCH,
> -
> -	/* PASID entry is invalid or has configuration errors */
> -	IOMMU_FAULT_REASON_BAD_PASID_ENTRY,
> -
> -	/*
> -	 * PASID is out of range (e.g. exceeds the maximum PASID
> -	 * supported by the IOMMU) or disabled.
> -	 */
> -	IOMMU_FAULT_REASON_PASID_INVALID,
> -
> -	/*
> -	 * An external abort occurred fetching (or updating) a translation
> -	 * table descriptor
> -	 */
> -	IOMMU_FAULT_REASON_WALK_EABT,
> -
> -	/*
> -	 * Could not access the page table entry (Bad address),
> -	 * actual translation fault
> -	 */
> -	IOMMU_FAULT_REASON_PTE_FETCH,
> -
> -	/* Protection flag check failed */
> -	IOMMU_FAULT_REASON_PERMISSION,
> -
> -	/* access flag check failed */
> -	IOMMU_FAULT_REASON_ACCESS,
> -
> -	/* Output address of a translation stage caused Address Size fault */
> -	IOMMU_FAULT_REASON_OOR_ADDRESS,
> -};
> -
> -/**
> - * struct iommu_fault_unrecoverable - Unrecoverable fault data
> - * @reason: reason of the fault, from &enum iommu_fault_reason
> - * @flags: parameters of this fault (IOMMU_FAULT_UNRECOV_* values)
> - * @pasid: Process Address Space ID
> - * @perm: requested permission access using by the incoming transaction
> - *        (IOMMU_FAULT_PERM_* values)
> - * @addr: offending page address
> - * @fetch_addr: address that caused a fetch abort, if any
> - */
> -struct iommu_fault_unrecoverable {
> -	__u32	reason;
> -#define IOMMU_FAULT_UNRECOV_PASID_VALID		(1 << 0)
> -#define IOMMU_FAULT_UNRECOV_ADDR_VALID		(1 << 1)
> -#define IOMMU_FAULT_UNRECOV_FETCH_ADDR_VALID	(1 << 2)
> -	__u32	flags;
> -	__u32	pasid;
> -	__u32	perm;
> -	__u64	addr;
> -	__u64	fetch_addr;
> -};
> -
>   /**
>    * struct iommu_fault_page_request - Page Request data
>    * @flags: encodes whether the corresponding fields are valid and whether this
> @@ -142,19 +82,11 @@ struct iommu_fault_page_request {
>   /**
>    * struct iommu_fault - Generic fault data
>    * @type: fault type from &enum iommu_fault_type
> - * @padding: reserved for future use (should be zero)
> - * @event: fault event, when @type is %IOMMU_FAULT_DMA_UNRECOV
>    * @prm: Page Request message, when @type is %IOMMU_FAULT_PAGE_REQ
> - * @padding2: sets the fault size to allow for future extensions
>    */
>   struct iommu_fault {
>   	__u32	type;
> -	__u32	padding;
> -	union {
> -		struct iommu_fault_unrecoverable event;
> -		struct iommu_fault_page_request prm;
> -		__u8 padding2[56];
> -	};
> +	struct iommu_fault_page_request prm;
>   };
>   
>   /**

-- 
Regards,
Yi Liu