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

[AKASHI Takahiro <takahiro.akashi@linaro.org>]

On Thu, Dec 27, 2018 at 05:58:49AM +0100, Heinrich Schuchardt wrote:
> On 12/18/18 6:02 AM, AKASHI Takahiro wrote:
> > See UEFI v2.7, section 3.1.2 for details of the specification.
> > 
> > With my efishell command[1], 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 setvar BootNext =H0200
> 
> If you already have an "efi boot" sub-command wouldn't the following
> syntax make more sense?
> 
>     efi boot next 2

OK.

> 
> 
> Best regards
> 
> Heinrich
> 
> >   => efi bootmgr
> >      (starting HELLO ...)
> >   => efi dumpvar
> >   <snip ...>
> >   BootCurrent: {boot,run}(blob)
> >   00000000:  02 00                    ..
> >   BootOrder: {boot,run}(blob)
> >   00000000:  01 00 02 00              ....
> > 
> > Using "run -e" would be more human-friendly, though.
> > 
> > [1] https://lists.denx.de/pipermail/u-boot/2018-November/346450.html
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > ---
> >  lib/efi_loader/efi_bootmgr.c | 37 +++++++++++++++++++++++++++++++++++-
> >  1 file changed, 36 insertions(+), 1 deletion(-)
> > 
> > diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
> > index a095df3f540b..a54ae28343ce 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 +183,41 @@ error:
> >  void *efi_bootmgr_load(struct efi_device_path **device_path,
> >  		       struct efi_device_path **file_path)
> >  {
> > -	uint16_t *bootorder;
> > +	u16 bootnext, *bootorder;
> > +	u32 attributes;
> >  	efi_uintn_t size;
> >  	void *image = NULL;
> >  	int i, num;
> > +	efi_status_t ret;
> >  
> >  	__efi_entry_check();
> >  
> >  	bs = systab.boottime;
> >  	rs = systab.runtime;
> >  
> > +	/* 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;
> > +
> > +	attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
> > +		     EFI_VARIABLE_RUNTIME_ACCESS;
> 
> According to the UEFI spec you do not need any attributes when deleting
> a variable.

OK.

> Please, add a comment describing what you are doing here:
> 
> /* Delete BootNext variable */

OK.

-Takahiro Akashi


> Best regards
> 
> Heinrich
> 
> > +	size = 0;
> > +	ret = rs->set_variable(L"BootNext",
> > +			       (efi_guid_t *)&efi_global_variable_guid,
> > +			       attributes, size, &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;
> > 
>