[PATCH v6 7/9] ACPI: APEI: EINJ: Add debugfs files for EINJv2 support

[Zaid Alali <zaidal@xxxxxxxxxxxxxxxxxxxxxx>]

Create a debugfs blob file to be used for reading the user
input for the component array. EINJv2 enables users to inject
errors to multiple components/devices at the same time using
component array.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Zaid Alali <zaidal@xxxxxxxxxxxxxxxxxxxxxx>
---
 drivers/acpi/apei/einj-core.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c
index fde6e01f66eb..2c22615ac72c 100644
--- a/drivers/acpi/apei/einj-core.c
+++ b/drivers/acpi/apei/einj-core.c
@@ -33,6 +33,7 @@
 #define SLEEP_UNIT_MAX		5000			/* 5ms */
 /* Firmware should respond within 1 seconds */
 #define FIRMWARE_TIMEOUT	(1 * USEC_PER_SEC)
+#define COMP_ARR_SIZE		1024
 #define ACPI65_EINJV2_SUPP	BIT(30)
 #define ACPI5_VENDOR_BIT	BIT(31)
 #define MEM_ERROR_MASK		(ACPI_EINJ_MEMORY_CORRECTABLE | \
@@ -107,6 +108,8 @@ static struct debugfs_blob_wrapper vendor_blob;
 static struct debugfs_blob_wrapper vendor_errors;
 static char vendor_dev[64];
 
+static struct debugfs_blob_wrapper einjv2_component_arr;
+static void *user_input;
 static u32 available_error_type;
 static u32 available_error_type_v2;
 
@@ -689,6 +692,7 @@ static u64 error_param3;
 static u64 error_param4;
 static struct dentry *einj_debug_dir;
 static char einj_buf[32];
+static bool EINJv2_enabled;
 static struct { u32 mask; const char *str; } const einj_error_type_string[] = {
 	{ BIT(0), "Processor Correctable" },
 	{ BIT(1), "Processor Uncorrectable non-fatal" },
@@ -718,7 +722,7 @@ static int available_error_type_show(struct seq_file *m, void *v)
 		if (available_error_type & einj_error_type_string[pos].mask)
 			seq_printf(m, "0x%08x\t%s\n", einj_error_type_string[pos].mask,
 				   einj_error_type_string[pos].str);
-	if (available_error_type & ACPI65_EINJV2_SUPP) {
+	if ((available_error_type & ACPI65_EINJV2_SUPP) && EINJv2_enabled) {
 		for (int pos = 0; pos < ARRAY_SIZE(einjv2_error_type_string); pos++) {
 			if (available_error_type_v2 & einjv2_error_type_string[pos].mask)
 				seq_printf(m, "V2_0x%08x\t%s\n", einjv2_error_type_string[pos].mask,
@@ -901,8 +905,22 @@ static int __init einj_probe(struct platform_device *pdev)
 				   &error_param4);
 		debugfs_create_x32("notrigger", S_IRUSR | S_IWUSR,
 				   einj_debug_dir, &notrigger);
+		if (available_error_type & ACPI65_EINJV2_SUPP) {
+			user_input = kzalloc(COMP_ARR_SIZE, GFP_KERNEL);
+			if (!user_input) {
+				EINJv2_enabled = false;
+				pr_info("EINJv2 is disabled: not enough memory\n");
+				goto skip_EINJv2;
+			}
+			EINJv2_enabled = true;
+			einjv2_component_arr.data = user_input;
+			einjv2_component_arr.size = COMP_ARR_SIZE;
+			debugfs_create_blob("einjv2_component_array", S_IRUSR | S_IWUSR,
+					einj_debug_dir, &einjv2_component_arr);
+		}
 	}
 
+skip_EINJv2:
 	if (vendor_dev[0]) {
 		vendor_blob.data = vendor_dev;
 		vendor_blob.size = strlen(vendor_dev);
@@ -944,6 +962,7 @@ static void __exit einj_remove(struct platform_device *pdev)
 		if (vendor_errors.size)
 			acpi_os_unmap_memory(vendor_errors.data, vendor_errors.size);
 	}
+	kfree(user_input);
 	einj_exec_ctx_init(&ctx);
 	apei_exec_post_unmap_gars(&ctx);
 	apei_resources_release(&einj_resources);
-- 
2.43.0