[U-Boot] [RFC 3/8] efi_loader: bootmgr: return pointer and size of buffer in loading

Heinrich Schuchardt
2019-03-21T11:41:06Z

On 3/5/19 6:53 AM, AKASHI Takahiro wrote:
> We need to know the size of image loaded so as to be able to use
> load_image() API at do_bootefi_exec() in a later patch.
>
> So change the interface of efi_bootmgr_load().
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
> include/efi_loader.h | 5 +++--
> lib/efi_loader/efi_bootmgr.c | 41 +++++++++++++++++++++---------------
> 2 files changed, 27 insertions(+), 19 deletions(-)
>
> diff --git a/include/efi_loader.h b/include/efi_loader.h
> index 47a51ddc9406..3f51116155ad 100644
> --- a/include/efi_loader.h
> +++ b/include/efi_loader.h
> @@ -564,8 +564,9 @@ struct efi_load_option {
>
> void efi_deserialize_load_option(struct efi_load_option *lo, u8 *data);
> unsigned long efi_serialize_load_option(struct efi_load_option *lo, u8 **data);
> -void *efi_bootmgr_load(struct efi_device_path **device_path,
> - struct efi_device_path **file_path);
> +efi_status_t efi_bootmgr_load(struct efi_device_path **device_path,
> + struct efi_device_path **file_path,
> + void **image, efi_uintn_t *size);
>
> #else /* CONFIG_IS_ENABLED(EFI_LOADER) */
>
> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
> index 1575c5c09e46..38f3fa15f6ef 100644
> --- a/lib/efi_loader/efi_bootmgr.c
> +++ b/lib/efi_loader/efi_bootmgr.c
> @@ -120,14 +120,17 @@ static void *get_var(u16 *name, const efi_guid_t *vendor,
> * if successful. This checks that the EFI_LOAD_OPTION is active (enabled)
> * and that the specified file to boot exists.
> */
> -static void *try_load_entry(uint16_t n, struct efi_device_path **device_path,
> - struct efi_device_path **file_path)
> +static efi_status_t try_load_entry(u16 n,
> + struct efi_device_path **device_path,
> + struct efi_device_path **file_path,
> + void **image, efi_uintn_t *image_size)
> {
> struct efi_load_option lo;
> u16 varname[] = L"Boot0000";
> u16 hexmap[] = L"0123456789ABCDEF";
> - void *load_option, *image = NULL;
> + void *load_option;
> efi_uintn_t size;
> + efi_status_t ret;
>
> varname[4] = hexmap[(n & 0xf000) >> 12];
> varname[5] = hexmap[(n & 0x0f00) >> 8];
> @@ -136,18 +139,17 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path,
>
> load_option = get_var(varname, &efi_global_variable_guid, &size);
> if (!load_option)
> - return NULL;
> + return EFI_LOAD_ERROR;
>
> efi_deserialize_load_option(&lo, load_option);
>
> if (lo.attributes & LOAD_OPTION_ACTIVE) {
> u32 attributes;
> - efi_status_t ret;
>
> debug("%s: trying to load \"%ls\" from %pD\n",
> __func__, lo.label, lo.file_path);
>
> - ret = efi_load_image_from_path(lo.file_path, &image, &size);
> + ret = efi_load_image_from_path(lo.file_path, image, image_size);
>

This call to efi_load_image_from_path() leads to duplication of logic.

Why don't we simply call EFI_CALL(efi_load_image())) here and if it
succeeds return from efi_bootmgr_load()?

Best regards

Heinrich

> if (ret != EFI_SUCCESS)
> goto error;
> @@ -164,12 +166,14 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path,
>
> printf("Booting: %ls\n", lo.label);
> efi_dp_split_file_path(lo.file_path, device_path, file_path);
> + } else {
> + ret = EFI_LOAD_ERROR;
> }
>
> error:
> free(load_option);
>
> - return image;
> + return ret;
> }
>
> /*
> @@ -177,12 +181,12 @@ error:
> * EFI variable, the available load-options, finding and returning
> * the first one that can be loaded successfully.
> */
> -void *efi_bootmgr_load(struct efi_device_path **device_path,
> - struct efi_device_path **file_path)
> +efi_status_t efi_bootmgr_load(struct efi_device_path **device_path,
> + struct efi_device_path **file_path,
> + void **image, efi_uintn_t *image_size)
> {
> u16 bootnext, *bootorder;
> efi_uintn_t size;
> - void *image = NULL;
> int i, num;
> efi_status_t ret;
>
> @@ -201,9 +205,9 @@ void *efi_bootmgr_load(struct efi_device_path **device_path,
> (efi_guid_t *)&efi_global_variable_guid,
> 0, 0, &bootnext));
> if (ret == EFI_SUCCESS) {
> - image = try_load_entry(bootnext,
> - device_path, file_path);
> - if (image)
> + ret = try_load_entry(bootnext, device_path, file_path,
> + image, image_size);
> + if (ret == EFI_SUCCESS)
> goto error;
> }
> }
> @@ -212,19 +216,22 @@ void *efi_bootmgr_load(struct efi_device_path **device_path,
> bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size);
> if (!bootorder) {
> printf("BootOrder not defined\n");
> + ret = EFI_NOT_FOUND;
> goto error;
> }
>
> num = size / sizeof(uint16_t);
> for (i = 0; i < num; i++) {
> - debug("%s: trying to load Boot%04X\n", __func__, bootorder[i]);
> - image = try_load_entry(bootorder[i], device_path, file_path);
> - if (image)
> + debug("%s: trying to load Boot%04X\n", __func__,
> + bootorder[i]);
> + ret = try_load_entry(bootorder[i], device_path, file_path,
> + image, image_size);
> + if (ret == EFI_SUCCESS)
> break;
> }
>
> free(bootorder);
>
> error:
> - return image;
> + return ret;
> }
>