[PATCH 1/2] efi_loader: support booting via short-form device-path

[Heinrich Schuchardt]

The boot manager must support loading from boot options using a short-form
device-path, e.g. one where the first element is a hard drive media path.

See '3.1.2 Load Options Processing' in UEFI specification version 2.9.

Fixes: 0e074d12393b ("efi_loader: carve out efi_load_image_from_file()")
Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
 lib/efi_loader/efi_boottime.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 82128ac1d5..173e636d60 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -1940,7 +1940,7 @@ efi_status_t efi_load_image_from_path(bool boot_policy,
 {
 	efi_handle_t device;
 	efi_status_t ret;
-	struct efi_device_path *dp;
+	struct efi_device_path *dp, *rem;
 	struct efi_load_file_protocol *load_file_protocol = NULL;
 	efi_uintn_t buffer_size;
 	uint64_t addr, pages;
@@ -1951,18 +1951,18 @@ efi_status_t efi_load_image_from_path(bool boot_policy,
 	*size = 0;

 	dp = file_path;
-	ret = EFI_CALL(efi_locate_device_path(
-		       &efi_simple_file_system_protocol_guid, &dp, &device));
+	device = efi_dp_find_obj(dp, &rem);
+	ret = efi_search_protocol(device, &efi_simple_file_system_protocol_guid,
+				  NULL);
 	if (ret == EFI_SUCCESS)
 		return efi_load_image_from_file(file_path, buffer, size);

-	ret = EFI_CALL(efi_locate_device_path(
-		       &efi_guid_load_file_protocol, &dp, &device));
+	ret = efi_search_protocol(device, &efi_guid_load_file_protocol, NULL);
 	if (ret == EFI_SUCCESS) {
 		guid = &efi_guid_load_file_protocol;
 	} else if (!boot_policy) {
 		guid = &efi_guid_load_file2_protocol;
-		ret = EFI_CALL(efi_locate_device_path(guid, &dp, &device));
+		ret = efi_search_protocol(device, guid, NULL);
 	}
 	if (ret != EFI_SUCCESS)
 		return EFI_NOT_FOUND;
--
2.34.1