Commit 691a0f0a authored by Zaid Alali's avatar Zaid Alali Committed by Rafael J. Wysocki
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ACPI: APEI: EINJ: Discover EINJv2 parameters 



The EINJv2 set_error_type_with_address structure has a flex array
to hold the component IDs and syndrome values used when injecting
multiple errors at once.

Discover the size of this array by taking the address from the
ACPI_EINJ_SET_ERROR_TYPE_WITH_ADDRESS entry in the EINJ table
and reading the BIOS copy of the structure.

Derive the maximum number of components from the length field
in the einjv2_extension_struct at the end of the BIOS copy.

Map the whole of the structure into kernel memory (and unmap
on module unload).

[Tony: Code unchanged from Zaid's original. New commit message]

Reviewed-by: default avatarTony Luck <tony.luck@intel.com>
Reviewed-by: default avatarIra Weiny <ira.weiny@intel.com>
Signed-off-by: default avatarZaid Alali <zaidal@os.amperecomputing.com>
Link: https://patch.msgid.link/20250617193026.637510-5-zaidal@os.amperecomputing.com


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 21cd921b

drivers/acpi/apei/einj-core.c

+24 −2
Original line number Diff line number Diff line
@@ -108,6 +108,7 @@ static struct debugfs_blob_wrapper vendor_blob; 
static struct debugfs_blob_wrapper vendor_errors;

static char vendor_dev[64];



static u32 max_nr_components;

static u32 available_error_type;

static u32 available_error_type_v2;
@@ -178,6 +179,7 @@ static DEFINE_MUTEX(einj_mutex); 
bool einj_initialized __ro_after_init;



static void __iomem *einj_param;

static u32 v5param_size;



static void einj_exec_ctx_init(struct apei_exec_context *ctx)

{
@@ -302,11 +304,31 @@ static void __iomem *einj_get_parameter_address(void) 
		struct set_error_type_with_address v5param;

		struct set_error_type_with_address __iomem *p;



		v5param_size = sizeof(v5param);

		p = acpi_os_map_iomem(pa_v5, sizeof(*p));

		if (p) {

			memcpy_fromio(&v5param, p, sizeof(v5param));

			int offset, len;



			memcpy_fromio(&v5param, p, v5param_size);

			acpi5 = 1;

			check_vendor_extension(pa_v5, &v5param);

			if (available_error_type & ACPI65_EINJV2_SUPP) {

				len = v5param.einjv2_struct.length;

				offset = offsetof(struct einjv2_extension_struct, component_arr);

				max_nr_components = (len - offset) /

						sizeof(v5param.einjv2_struct.component_arr[0]);

				/*

				 * The first call to acpi_os_map_iomem above does not include the

				 * component array, instead it is used to read and calculate maximum

				 * number of components supported by the system. Below, the mapping

				 * is expanded to include the component array.

				 */

				acpi_os_unmap_iomem(p, v5param_size);

				offset = offsetof(struct set_error_type_with_address, einjv2_struct);

				v5param_size = offset + struct_size(&v5param.einjv2_struct,

					component_arr, max_nr_components);

				p = acpi_os_map_iomem(pa_v5, v5param_size);

			}

			return p;

		}

	}
@@ -933,7 +955,7 @@ static void __exit einj_remove(struct faux_device *fdev) 


	if (einj_param) {

		acpi_size size = (acpi5) ?

			sizeof(struct set_error_type_with_address) :

			v5param_size :

			sizeof(struct einj_parameter);



		acpi_os_unmap_iomem(einj_param, size);