[PATCH v8 3/4] Boot var automatic management for removable medias

[AKASHI Takahiro]

On Tue, Jun 06, 2023 at 09:37:20AM -0700, Raymond Mao wrote:
> Changes for complying to EFI spec §3.5.1.1
> 'Removable Media Boot Behavior'.
> Boot variables can be automatically generated during a removable
> media is probed. At the same time, unused boot variables will be
> detected and removed.
> Please note that currently the function 'efi_disk_remove' is being
> invoked during exiting U-Boot and booting an OS - that is why we
> don't add the boot variables management inside 'efi_disk_remove'.

It's not accurate.
For instance, a user may run "scsi scan" or "usb reset" to re-enumerate
devices added (or removed). They will invoke "remove" against pre-existing
devices before invoking a "probe" routine.

So the text above doesn't justify not implementing "remove" hook.

-Takahiro Akashi

> Signed-off-by: Raymond Mao <raymond.mao at linaro.org>
> Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
> Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> ---
> Changes in v3
> - Split the patch into moving and renaming functions and
>   individual patches for each changed functionality
> Changes in v5
> - Move function call of efi_bootmgr_update_media_device_boot_option()
>   from efi_init_variables() to efi_init_obj_list()
> Changes in v6
> - Revert unrelated changes
> Changes in v7
> - adapt the return code of function
>   efi_bootmgr_update_media_device_boot_option()
> Changes in v8
> - add a note in the commit message for future reference
> 
>  lib/efi_loader/efi_disk.c  | 7 +++++++
>  lib/efi_loader/efi_setup.c | 5 +++++
>  2 files changed, 12 insertions(+)
> 
> diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
> index d2256713a8..d9b48ecf64 100644
> --- a/lib/efi_loader/efi_disk.c
> +++ b/lib/efi_loader/efi_disk.c
> @@ -687,6 +687,13 @@ int efi_disk_probe(void *ctx, struct event *event)
>  			return -1;
>  	}
>  
> +	/* only do the boot option management when UEFI sub-system is initialized */
> +	if (efi_obj_list_initialized == EFI_SUCCESS) {
> +		ret = efi_bootmgr_update_media_device_boot_option();
> +		if (ret != EFI_SUCCESS)
> +			return -1;
> +	}
> +
>  	return 0;
>  }
>  
> diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
> index 58d4e13402..877f3878d6 100644
> --- a/lib/efi_loader/efi_setup.c
> +++ b/lib/efi_loader/efi_setup.c
> @@ -245,6 +245,11 @@ efi_status_t efi_init_obj_list(void)
>  	if (ret != EFI_SUCCESS)
>  		goto out;
>  
> +	/* update boot option after variable service initialized */
> +	ret = efi_bootmgr_update_media_device_boot_option();
> +	if (ret != EFI_SUCCESS)
> +		goto out;
> +
>  	/* Define supported languages */
>  	ret = efi_init_platform_lang();
>  	if (ret != EFI_SUCCESS)
> -- 
> 2.25.1
>