The Confidential Computing Event Log (CCEL) table provides the address
and length of the CCEL records area in UEFI reserved memory.
To allow user space access to these records, expose a sysfs interface
similar to the BERT table.
More details about the CCEL table can be found in the ACPI specification
r6.5 [1], sec 5.2.34.
Link: https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#cc-event-log-acpi-table # [1]
Co-developed-by: Haibo Xu <[email protected]>
Signed-off-by: Haibo Xu <[email protected]>
Signed-off-by: Kuppuswamy Sathyanarayanan <[email protected]>
---
Changes since v2:
* Fixed the commit log as per review suggestion.
Changes since v1:
* Removed unnecessary parenthesis as per Rafael's suggestion.
drivers/acpi/sysfs.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
index 7f4ff56c9d42..687524b50085 100644
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -458,11 +458,28 @@ static int acpi_bert_data_init(void *th, struct acpi_data_attr *data_attr)
return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr);
}
+static int acpi_ccel_data_init(void *th, struct acpi_data_attr *data_attr)
+{
+ struct acpi_table_ccel *ccel = th;
+
+ if (ccel->header.length < sizeof(struct acpi_table_ccel) ||
+ !ccel->log_area_start_address || !ccel->log_area_minimum_length) {
+ kfree(data_attr);
+ return -EINVAL;
+ }
+ data_attr->addr = ccel->log_area_start_address;
+ data_attr->attr.size = ccel->log_area_minimum_length;
+ data_attr->attr.attr.name = "CCEL";
+
+ return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr);
+}
+
static struct acpi_data_obj {
char *name;
int (*fn)(void *, struct acpi_data_attr *);
} acpi_data_objs[] = {
{ ACPI_SIG_BERT, acpi_bert_data_init },
+ { ACPI_SIG_CCEL, acpi_ccel_data_init },
};
#define NUM_ACPI_DATA_OBJS ARRAY_SIZE(acpi_data_objs)
--
2.34.1
On Wed, Mar 22, 2023 at 8:13 PM Kuppuswamy Sathyanarayanan
<[email protected]> wrote:
>
> The Confidential Computing Event Log (CCEL) table provides the address
> and length of the CCEL records area in UEFI reserved memory.
>
> To allow user space access to these records, expose a sysfs interface
> similar to the BERT table.
>
> More details about the CCEL table can be found in the ACPI specification
> r6.5 [1], sec 5.2.34.
>
> Link: https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#cc-event-log-acpi-table # [1]
> Co-developed-by: Haibo Xu <[email protected]>
> Signed-off-by: Haibo Xu <[email protected]>
> Signed-off-by: Kuppuswamy Sathyanarayanan <[email protected]>
> ---
>
> Changes since v2:
> * Fixed the commit log as per review suggestion.
>
> Changes since v1:
> * Removed unnecessary parenthesis as per Rafael's suggestion.
>
> drivers/acpi/sysfs.c | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
> index 7f4ff56c9d42..687524b50085 100644
> --- a/drivers/acpi/sysfs.c
> +++ b/drivers/acpi/sysfs.c
> @@ -458,11 +458,28 @@ static int acpi_bert_data_init(void *th, struct acpi_data_attr *data_attr)
> return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr);
> }
>
> +static int acpi_ccel_data_init(void *th, struct acpi_data_attr *data_attr)
> +{
> + struct acpi_table_ccel *ccel = th;
> +
> + if (ccel->header.length < sizeof(struct acpi_table_ccel) ||
> + !ccel->log_area_start_address || !ccel->log_area_minimum_length) {
> + kfree(data_attr);
> + return -EINVAL;
> + }
> + data_attr->addr = ccel->log_area_start_address;
> + data_attr->attr.size = ccel->log_area_minimum_length;
> + data_attr->attr.attr.name = "CCEL";
> +
> + return sysfs_create_bin_file(tables_data_kobj, &data_attr->attr);
> +}
> +
> static struct acpi_data_obj {
> char *name;
> int (*fn)(void *, struct acpi_data_attr *);
> } acpi_data_objs[] = {
> { ACPI_SIG_BERT, acpi_bert_data_init },
> + { ACPI_SIG_CCEL, acpi_ccel_data_init },
> };
>
> #define NUM_ACPI_DATA_OBJS ARRAY_SIZE(acpi_data_objs)
> --
Applied as 6.4 material, thanks!