Re: [RFC PATCH 4/5] ACPI: APEI: EINJ: Enable EINJv2 error injections

[John Allen <john.allen@amd.com>]

On Tue, Mar 12, 2024 at 02:26:25PM -0700, Zaid Alali wrote:
> This commit enable the driver to inject EINJv2 type errors.

Same with other commits, commit descriptions should be in imperative
mood. For this one I might say something like, "Support injecting EINJv2
type errors." or something along those lines.

> The component array values are parsed from user_input and expected
> to contain hex values for component id and syndrom seperated by

s/syndrom/syndrome

> space, and multiple components are separated by new line.
> 
> for example:
> component_id1 component_syndrom1

s/syndrom/syndrome

Same for the below lines.

> component_id2 component_syndrom2
>  :
> component_id(n) component_syndrom(n)

This interface seems a bit clunky, but I can't think of a way a better
way to do it right now. Can you provide an example of how a user would
write to the component array file? This would be a good addition to the
example in the documentation provided in patch 5/5.

> 
> Signed-off-by: Zaid Alali <zaidal@os.amperecomputing.com>
> ---
>  drivers/acpi/apei/einj.c | 89 ++++++++++++++++++++++++++++++++++++----
>  1 file changed, 80 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/acpi/apei/einj.c b/drivers/acpi/apei/einj.c
> index ceac53aa0d3f..9e31bf707ced 100644
> --- a/drivers/acpi/apei/einj.c
> +++ b/drivers/acpi/apei/einj.c
> @@ -80,6 +80,13 @@ enum {
>  	SETWA_FLAGS_APICID = 1,
>  	SETWA_FLAGS_MEM = 2,
>  	SETWA_FLAGS_PCIE_SBDF = 4,
> +	SETWA_FLAGS_EINJV2 = 8,
> +};
> +
> +enum {
> +	EINJV2_PROCESSOR_ERROR = 0x1,
> +	EINJV2_MEMORY_ERROR = 0x2,
> +	EINJV2_PCIE_ERROR = 0x4,
>  };
>  
>  /*
> @@ -104,6 +111,7 @@ static char vendor_dev[64];
>  static struct debugfs_blob_wrapper einjv2_component_arr;
>  static u64 component_count;
>  static void *user_input;
> +static int nr_components;
>  
>  /*
>   * Some BIOSes allow parameters to the SET_ERROR_TYPE entries in the
> @@ -275,11 +283,20 @@ static void *einj_get_parameter_address(void)
>  	}
>  	if (pa_v5) {
>  		struct set_error_type_with_address *v5param;
> -
>  		v5param = acpi_os_map_iomem(pa_v5, sizeof(*v5param));
>  		if (v5param) {
> +			int offset, len;
> +
>  			acpi5 = 1;
>  			check_vendor_extension(pa_v5, v5param);
> +			if (error_type & ACPI65_EINJV2_SUPP) {
> +				len = v5param->einjv2_struct.length;
> +				offset = offsetof(struct einjv2_extension_struct, component_arr);
> +				nr_components = (len-offset)/32;

Binary operators like '-' and '/' should have a single space on either
side:
	nr_components = (len - offset) / 32;

Some places have this right, but there are a number of other places in
the series that should fix this as well.

> +				acpi_os_unmap_iomem(v5param, sizeof(*v5param));
> +				v5param = acpi_os_map_iomem(pa_v5, sizeof(*v5param) + (
> +					(nr_components) * sizeof(struct syndrome_array)));
> +			}
>  			return v5param;
>  		}
>  	}
> @@ -485,10 +502,47 @@ static int __einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
>  			v5param->flags = vendor_flags;
>  		} else if (flags) {
>  			v5param->flags = flags;
> -			v5param->memory_address = param1;
> -			v5param->memory_address_range = param2;
> -			v5param->apicid = param3;
> -			v5param->pcie_sbdf = param4;
> +			if (flags & SETWA_FLAGS_MEM) {
> +				v5param->memory_address = param1;
> +				v5param->memory_address_range = param2;
> +			}
> +			if (flags & SETWA_FLAGS_EINJV2) {
> +				if (component_count > nr_components)
> +					return -EINVAL;
> +
> +				v5param->einjv2_struct.component_arr_count = component_count;
> +				int count = 0, bytes_read, pos = 0;
> +				unsigned int comp, synd;
> +				struct syndrome_array *component_arr;
> +
> +				component_arr = v5param->einjv2_struct.component_arr;
> +				while (sscanf(user_input+pos, "%x %x\n%n", &comp, &synd,
> +							&bytes_read) == 2) {
> +					count++;
> +					pos += bytes_read;
> +					if (count > component_count)
> +						return -EINVAL;
> +
> +					switch (type) {
> +					case EINJV2_PROCESSOR_ERROR:
> +						component_arr[count-1].comp_id.acpi_id = comp;
> +						component_arr[count-1].comp_synd.proc_synd = synd;
> +						break;
> +					case EINJV2_MEMORY_ERROR:
> +						component_arr[count-1].comp_id.device_id = comp;
> +						component_arr[count-1].comp_synd.mem_synd = synd;
> +						break;
> +					case EINJV2_PCIE_ERROR:
> +						component_arr[count-1].comp_id.pcie_sbdf = comp;
> +						component_arr[count-1].comp_synd.pcie_synd = synd;
> +						break;

Nesting is getting pretty deep here. A separate function for parsing the
component array could improve readability.

> +					}
> +				}
> +

Remove unneeded new line above.

Thanks,
John

> +			} else {
> +				v5param->apicid = param3;
> +				v5param->pcie_sbdf = param4;
> +			}
>  		} else {
>  			switch (type) {
>  			case ACPI_EINJ_PROCESSOR_CORRECTABLE:
> @@ -572,9 +626,19 @@ static int einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
>  
>  	/* If user manually set "flags", make sure it is legal */
>  	if (flags && (flags &
> -		~(SETWA_FLAGS_APICID|SETWA_FLAGS_MEM|SETWA_FLAGS_PCIE_SBDF)))
> +		~(SETWA_FLAGS_APICID|SETWA_FLAGS_MEM|SETWA_FLAGS_PCIE_SBDF|SETWA_FLAGS_EINJV2)))
>  		return -EINVAL;
>  
> +	/*check if type is a valid EINJv2 error type*/
> +	if (flags & SETWA_FLAGS_EINJV2) {
> +		u32 error_type;
> +
> +		rc = einj_get_available_error_type(&error_type, ACPI_EINJV2_GET_ERROR_TYPE);
> +		if (rc)
> +			return rc;
> +		if (!(type & error_type))
> +			return -EINVAL;
> +	}
>  	/*
>  	 * We need extra sanity checks for memory errors.
>  	 * Other types leap directly to injection.
> @@ -694,7 +758,7 @@ static int error_type_get(void *data, u64 *val)
>  static int error_type_set(void *data, u64 val)
>  {
>  	int rc;
> -	u32 available_error_type = 0;
> +	u32 available_error_type = 0, available_error_type_v2 = 0;
>  	u32 tval, vendor;
>  
>  	/* Only low 32 bits for error type are valid */
> @@ -716,7 +780,13 @@ static int error_type_set(void *data, u64 val)
>  				ACPI_EINJ_GET_ERROR_TYPE);
>  		if (rc)
>  			return rc;
> -		if (!(val & available_error_type))
> +		if (available_error_type & ACPI65_EINJV2_SUPP) {
> +			rc = einj_get_available_error_type(&available_error_type_v2,
> +					ACPI_EINJV2_GET_ERROR_TYPE);
> +			if (rc)
> +				return rc;
> +		}
> +		if (!(val & (available_error_type | available_error_type_v2)))
>  			return -EINVAL;
>  	}
>  	error_type = val;
> @@ -886,7 +956,8 @@ static void __exit einj_exit(void)
>  			sizeof(struct set_error_type_with_address) :
>  			sizeof(struct einj_parameter);
>  
> -		acpi_os_unmap_iomem(einj_param, size);
> +		acpi_os_unmap_iomem(einj_param,
> +				size+((nr_components) * sizeof(struct syndrome_array)));
>  		if (vendor_errors.size)
>  			acpi_os_unmap_memory(vendor_errors.data, vendor_errors.size);
>  	}
> -- 
> 2.34.1
>