[U-Boot] [PATCH v2 1/5] efi_loader: bootmgr: support BootNext and BootCurrent variable behavior

AKASHI Takahiro
2019-01-15T02:54:33Z

See UEFI v2.7, section 3.1.2 for details of the specification.

With my efitool command, you can try as the following:
=> efi boot add 1 SHELL ...
=> efi boot add 2 HELLO ...
=> efi boot order 1 2
=> efi bootmgr
(starting SHELL ...)
=> efi boot next 2
=> efi bootmgr
(starting HELLO ...)
=> efi dumpvar
<snip ...>
BootCurrent: {boot,run}(blob)
00000000: 02 00 ..
BootOrder: {boot,run}(blob)
00000000: 01 00 02 00 ....

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
lib/efi_loader/efi_bootmgr.c | 34 +++++++++++++++++++++++++++++++++-
1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
index a095df3f540b..6c5303736dc6 100644
--- a/lib/efi_loader/efi_bootmgr.c
+++ b/lib/efi_loader/efi_bootmgr.c
@@ -145,11 +145,21 @@ static void *try_load_entry(uint16_t n, struct efi_device_path **device_path,
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);

+ attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS;
+ size = sizeof(n);
+ ret = rs->set_variable(L"BootCurrent",
+ (efi_guid_t *)&efi_global_variable_guid,
+ attributes, size, &n);
+ if (ret != EFI_SUCCESS)
+ goto error;
+
ret = efi_load_image_from_path(lo.file_path, &image);

if (ret != EFI_SUCCESS)
@@ -173,16 +183,38 @@ error:
void *efi_bootmgr_load(struct efi_device_path **device_path,
struct efi_device_path **file_path)
{
- uint16_t *bootorder;
+ u16 bootnext, *bootorder;
efi_uintn_t size;
void *image = NULL;
int i, num;
+ efi_status_t ret;

__efi_entry_check();

bs = systab.boottime;
rs = systab.runtime;

+ /* get BootNext */
+ size = sizeof(bootnext);
+ ret = rs->get_variable(L"BootNext",
+ (efi_guid_t *)&efi_global_variable_guid,
+ NULL, &size, &bootnext);
+ if (!bootnext)
+ goto run_list;
+
+ /* delete BootNext */
+ ret = rs->set_variable(L"BootNext",
+ (efi_guid_t *)&efi_global_variable_guid,
+ 0, 0, &bootnext);
+ if (ret != EFI_SUCCESS)
+ goto error;
+
+ image = try_load_entry(bootnext, device_path, file_path);
+ if (image)
+ goto error;
+
+run_list:
+ /* BootOrder */
bootorder = get_var(L"BootOrder", &efi_global_variable_guid, &size);
if (!bootorder)
goto error;
--
2.19.1