[PATCH] efi_loader: use event callback for initrd deregistration

[Ilias Apalodimas]

Thanks for cleaning this up!

On Mon, 4 Dec 2023 at 06:31, Masahisa Kojima <masahisa.kojima at linaro.org> wrote:
>
> Currently efi_initrd_deregister() is called in bootefi.c
> when the image started from bootefi command returns.
> Since efi_guid_event_group_return_to_efibootmgr event is
> implemented, so let's use this event for invoking
> initrd deregistration.
>
> Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> ---
> Note that this patch can be applied to u-boot/next.
> This patch requires the patch e0d1a1ea68("efi_loader: add return to efibootmgr event group")
>
>  cmd/bootefi.c                    |  5 --
>  lib/efi_loader/efi_load_initrd.c | 82 +++++++++++++++++++++-----------
>  2 files changed, 55 insertions(+), 32 deletions(-)

Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>

>
> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
> index 4d74969ad6..e52bd3f743 100644
> --- a/cmd/bootefi.c
> +++ b/cmd/bootefi.c
> @@ -390,11 +390,6 @@ static efi_status_t do_bootefi_exec(efi_handle_t handle, void *load_options)
>  out:
>         free(load_options);
>
> -       if (IS_ENABLED(CONFIG_EFI_LOAD_FILE2_INITRD)) {
> -               if (efi_initrd_deregister() != EFI_SUCCESS)
> -                       log_err("Failed to remove loadfile2 for initrd\n");
> -       }
> -
>         /* Notify EFI_EVENT_GROUP_RETURN_TO_EFIBOOTMGR event group. */
>         list_for_each_entry(evt, &efi_events, link) {
>                 if (evt->group &&
> diff --git a/lib/efi_loader/efi_load_initrd.c b/lib/efi_loader/efi_load_initrd.c
> index 193433782c..7ca7785c04 100644
> --- a/lib/efi_loader/efi_load_initrd.c
> +++ b/lib/efi_loader/efi_load_initrd.c
> @@ -184,6 +184,50 @@ out:
>         return ret;
>  }
>
> +/**
> + * efi_initrd_deregister() - delete the handle for loading initial RAM disk
> + *
> + * This will delete the handle containing the Linux specific vendor device
> + * path and EFI_LOAD_FILE2_PROTOCOL for loading an initrd
> + *
> + * Return:     status code
> + */
> +efi_status_t efi_initrd_deregister(void)
> +{
> +       efi_status_t ret;
> +
> +       if (!efi_initrd_handle)
> +               return EFI_SUCCESS;
> +
> +       ret = efi_uninstall_multiple_protocol_interfaces(efi_initrd_handle,
> +                                                        /* initramfs */
> +                                                        &efi_guid_device_path,
> +                                                        &dp_lf2_handle,
> +                                                        /* LOAD_FILE2 */
> +                                                        &efi_guid_load_file2_protocol,
> +                                                        &efi_lf2_protocol,
> +                                                        NULL);
> +       efi_initrd_handle = NULL;
> +
> +       return ret;
> +}
> +
> +/**
> + * efi_initrd_return_notify() - return to efibootmgr callback
> + *
> + * @event:     the event for which this notification function is registered
> + * @context:   event context
> + */
> +static void EFIAPI efi_initrd_return_notify(struct efi_event *event,
> +                                                 void *context)
> +{
> +       efi_status_t ret;
> +
> +       EFI_ENTRY("%p, %p", event, context);
> +       ret = efi_initrd_deregister();
> +       EFI_EXIT(ret);
> +}
> +
>  /**
>   * efi_initrd_register() - create handle for loading initial RAM disk
>   *
> @@ -197,6 +241,7 @@ out:
>  efi_status_t efi_initrd_register(void)
>  {
>         efi_status_t ret;
> +       struct efi_event *event;
>
>         /*
>          * Allow the user to continue if Boot#### file path is not set for
> @@ -215,34 +260,17 @@ efi_status_t efi_initrd_register(void)
>                                                        &efi_guid_load_file2_protocol,
>                                                        &efi_lf2_protocol,
>                                                        NULL);
> +       if (ret != EFI_SUCCESS) {
> +               log_err("installing EFI_LOAD_FILE2_PROTOCOL failed\n");
> +               return ret;
> +       }
>
> -       return ret;
> -}
> -
> -/**
> - * efi_initrd_deregister() - delete the handle for loading initial RAM disk
> - *
> - * This will delete the handle containing the Linux specific vendor device
> - * path and EFI_LOAD_FILE2_PROTOCOL for loading an initrd
> - *
> - * Return:     status code
> - */
> -efi_status_t efi_initrd_deregister(void)
> -{
> -       efi_status_t ret;
> -
> -       if (!efi_initrd_handle)
> -               return EFI_SUCCESS;
> -
> -       ret = efi_uninstall_multiple_protocol_interfaces(efi_initrd_handle,
> -                                                        /* initramfs */
> -                                                        &efi_guid_device_path,
> -                                                        &dp_lf2_handle,
> -                                                        /* LOAD_FILE2 */
> -                                                        &efi_guid_load_file2_protocol,
> -                                                        &efi_lf2_protocol,
> -                                                        NULL);
> -       efi_initrd_handle = NULL;
> +       ret = efi_create_event(EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
> +                              efi_initrd_return_notify, NULL,
> +                              &efi_guid_event_group_return_to_efibootmgr,
> +                              &event);
> +       if (ret != EFI_SUCCESS)
> +               log_err("Creating event failed\n");
>
>         return ret;
>  }
>
> base-commit: 4a363dd516856344558034027e40d903868f67b4
> --
> 2.34.1
>