[PATCH 1/2 v2] efi: add a function to convert the status code to a string

[Ard Biesheuvel]

On Fri, 13 Dec 2019 at 10:07, Lee, Chun-Yi <joeyli.kernel at gmail.com> wrote:
>
> This function can be used to convert EFI status code to a string
> to improve the readability of log.
>
> v2:
> Moved the convert function to efi.c
>

Please put the patch series revision log below the ---

> Signed-off-by: "Lee, Chun-Yi" <jlee at suse.com>

Acked-by: Ard Biesheuvel <ardb at kernel.org>

> ---
>  drivers/firmware/efi/efi.c | 32 ++++++++++++++++++++++++++++++++
>  include/linux/efi.h        |  1 +
>  2 files changed, 33 insertions(+)
>
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index e98bbf8e56d9..8bdc1c17eb5d 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -954,6 +954,38 @@ int efi_status_to_err(efi_status_t status)
>         return err;
>  }
>
> +#define EFI_STATUS_STR(_status) \
> +       EFI_##_status : return "EFI_" __stringify(_status)
> +
> +const char *efi_status_to_str(efi_status_t status)
> +{
> +       switch (status) {
> +       case EFI_STATUS_STR(SUCCESS);
> +       case EFI_STATUS_STR(LOAD_ERROR);
> +       case EFI_STATUS_STR(INVALID_PARAMETER);
> +       case EFI_STATUS_STR(UNSUPPORTED);
> +       case EFI_STATUS_STR(BAD_BUFFER_SIZE);
> +       case EFI_STATUS_STR(BUFFER_TOO_SMALL);
> +       case EFI_STATUS_STR(NOT_READY);
> +       case EFI_STATUS_STR(DEVICE_ERROR);
> +       case EFI_STATUS_STR(WRITE_PROTECTED);
> +       case EFI_STATUS_STR(OUT_OF_RESOURCES);
> +       case EFI_STATUS_STR(NOT_FOUND);
> +       case EFI_STATUS_STR(ABORTED);
> +       case EFI_STATUS_STR(SECURITY_VIOLATION);
> +       }
> +       /*
> +        * There are two possibilities for this message to be exposed:
> +        * - Caller feeds a unknown status code from firmware.
> +        * - A new status code be defined in efi.h but we forgot to update
> +        *   this function.
> +        */
> +       pr_warn("Unknown efi status: 0x%lx\n", status);
> +
> +       return "Unknown efi status";
> +}
> +EXPORT_SYMBOL(efi_status_to_str);
> +
>  static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
>  static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
>
> diff --git a/include/linux/efi.h b/include/linux/efi.h
> index d87acf62958e..2c6848d2b112 100644
> --- a/include/linux/efi.h
> +++ b/include/linux/efi.h
> @@ -1228,6 +1228,7 @@ efi_capsule_pending(int *reset_type)
>  #endif
>
>  extern int efi_status_to_err(efi_status_t status);
> +extern const char *efi_status_to_str(efi_status_t status);
>
>  /*
>   * Variable Attributes
> --
> 2.16.4
>