Re: [PATCH v2 02/12] cmd: bootefi: re-organize do_bootefi()

Ilias Apalodimas
2023-12-05T08:55:07Z

Hello Akashi-san,
Thanks for taking a shot at the cleanup

On Tue, 21 Nov 2023 at 06:53, AKASHI Takahiro
<takahiro.akashi@linaro.org> wrote:
>
> Hi Heinrich,
>
> On Tue, Nov 21, 2023 at 04:31:40AM +0100, Heinrich Schuchardt wrote:
> > On 11/21/23 02:29, AKASHI Takahiro wrote:
> > > Replicate some code and re-organize do_bootefi() into three cases, which
> > > will be carved out as independent functions in the next two commits.
> > >
> > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > > ---
> > > cmd/Kconfig | 15 ++++++--
> > > cmd/bootefi.c | 82 ++++++++++++++++++++++++++++++--------------
> > > include/efi_loader.h | 2 --
> > > 3 files changed, 69 insertions(+), 30 deletions(-)
> > >
> > > diff --git a/cmd/Kconfig b/cmd/Kconfig
> > > index 6f636155e5b6..4cf9a210c4a1 100644
> > > --- a/cmd/Kconfig
> > > +++ b/cmd/Kconfig
> > > @@ -362,9 +362,19 @@ config CMD_BOOTEFI
> > > help
> > > Boot an EFI image from memory.
> > >
> > > +if CMD_BOOTEFI
> > > +config CMD_BOOTEFI_BINARY
> > > + bool "Allow booting an EFI binary directly"
> > > + depends on BOOTEFI_BOOTMGR
> >
> > Why should booting a known binary depend on the boot manager?
>
> Because I tried to maintain the meaning of CONFIG_BOOTEFI_BOOTMGR
> at this point of refactoring.
> This configuration will eventually be changed to
> config CMD_BOOTEFI_BINARY
> bool "Allow booting an EFI binary directly"
> depends on EFI_BINARY_EXEC
> default y
> in patch#9.
>
> > > + default y
> > > + help
> > > + Select this option to enable direct execution of binary at 'bootefi'.
> > > + This subcommand will allow you to load the UEFI binary using
> > > + other U-Boot commands or external methods and then run it.
> > > +
> > > config CMD_BOOTEFI_BOOTMGR
> > > bool "UEFI Boot Manager command"
> > > - depends on BOOTEFI_BOOTMGR && CMD_BOOTEFI
> > > + depends on BOOTEFI_BOOTMGR
> > > default y
> > > help
> > > Select this option to enable the 'bootmgr' subcommand of 'bootefi'.
> > > @@ -373,7 +383,7 @@ config CMD_BOOTEFI_BOOTMGR
> > >
> > > config CMD_BOOTEFI_HELLO_COMPILE
> > > bool "Compile a standard EFI hello world binary for testing"
> > > - depends on CMD_BOOTEFI && !CPU_V7M
> > > + depends on !CPU_V7M
> >
> > Why do we have this dependency?
>
> CPU_V7M?
> It was introduced in your commit:
> ---
> commit 0ea8741ff65e
> Author: Heinrich Schuchardt <xypron.glpk@gmx.de>
> Date: Sun Dec 30 10:11:14 2018 +0100
>
> efi_loader: CMD_BOOTEFI_HELLO_COMPILE in configs
> ---
>
> > EFI_LOADER cannot be selected for SYS_CPU=armv7m.
>
> If not needed, you can delete it, but it is out of scope
> of this patch series.
>
> > > default y
> > > help
> > > This compiles a standard EFI hello world application with U-Boot so
> > > @@ -395,6 +405,7 @@ config CMD_BOOTEFI_HELLO
> > > up EFI support on a new architecture.
> > >
> > > source lib/efi_selftest/Kconfig
> > > +endif
> > >
> > > config CMD_BOOTMENU
> > > bool "bootmenu"
> > > diff --git a/cmd/bootefi.c b/cmd/bootefi.c
> > > index 190ccba260e0..e9e5ab67a1f5 100644
> > > --- a/cmd/bootefi.c
> > > +++ b/cmd/bootefi.c
> > > @@ -503,7 +503,6 @@ out:
> > > return (ret != EFI_SUCCESS) ? ret : ret2;
> > > }
> > >
> > > -#ifdef CONFIG_CMD_BOOTEFI_SELFTEST
> > > static efi_status_t bootefi_run_prepare(const char *load_options_path,
> > > struct efi_device_path *device_path,
> > > struct efi_device_path *image_path,
> > > @@ -593,7 +592,6 @@ static int do_efi_selftest(void)
> > >
> > > return ret != EFI_SUCCESS;
> > > }
> > > -#endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
> > >
> > > /**
> > > * do_bootefi() - execute `bootefi` command
> > > @@ -615,14 +613,6 @@ static int do_bootefi(struct cmd_tbl *cmdtp, int flag, int argc,
> > > if (argc < 2)
> > > return CMD_RET_USAGE;
> > >
> > > - /* Initialize EFI drivers */
> > > - ret = efi_init_obj_list();
> > > - if (ret != EFI_SUCCESS) {
> > > - log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
> > > - ret & ~EFI_ERROR_MASK);
> > > - return CMD_RET_FAILURE;
> > > - }
> > > -
> > > if (argc > 2) {
> > > uintptr_t fdt_addr;
> > >
> > > @@ -631,29 +621,54 @@ static int do_bootefi(struct cmd_tbl *cmdtp, int flag, int argc,
> > > } else {
> > > fdt = EFI_FDT_USE_INTERNAL;
> > > }
> > > - ret = efi_install_fdt(fdt);
> > > - if (ret == EFI_INVALID_PARAMETER)
> > > - return CMD_RET_USAGE;
> > > - else if (ret != EFI_SUCCESS)
> > > - return CMD_RET_FAILURE;
> > >
> > > - if (IS_ENABLED(CONFIG_CMD_BOOTEFI_BOOTMGR)) {
> > > - if (!strcmp(argv[1], "bootmgr"))
> > > - return do_efibootmgr();
> > > + if (IS_ENABLED(CONFIG_CMD_BOOTEFI_BOOTMGR) &&
> > > + !strcmp(argv[1], "bootmgr")) {
> >
> >
> > https://docs.u-boot.org/en/latest/develop/commands.html
> > suggests to use U_BOOT_CMD_MKENT() to define sub-commands.
>
> As you know, these "if (!strcmp(argv[1], ...)" code exist since
> the early days when efi_selftest and bootmgr sub-commands were
> introduced in bootefi.
>
> In my personal preference, I would move bootmgr to a new independent
> command, efi_selftest to efidebug, leaving only binary-execution
> syntax in bootefi.
> (So no sub-command.)

And that's a good idea, does anything prevent us from doing that ? The
code works reliably as-is so if we are thinking about refactoring it,
take a deeper dive and let's do all of it.

An idea would be to start with patches that move 'bootefi hello' and
'bootefi selftest' to the efidebug command?

>
> >
> > > + /* Initialize EFI drivers */
> > > + ret = efi_init_obj_list();
> >
> > We should not duplicate this call for each sub-command.
>
> Please also take a look at the succeeding commits.
> A call to efi_init_obj_list() will be included in independent
> library functions, either efi_bootmgr_run(), efi_binary_run()
> or do_bootefi() (for efi_selftest) so that a caller of these
> functions doesn't have to know/care much about detailed APIs.

I am with Heinrich on this. Despite the further refactoring in
subsequent patches, we could just initialize the EFI subsystem at the
beginning. It will eventually be done by some part of u-boot and we
don't clean up the initialization on any failure, so why not move it
on top of the function right after the argument parsing?

>
> >
> > > + if (ret != EFI_SUCCESS) {
> > > + log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
> > > + ret & ~EFI_ERROR_MASK);
> > > + return CMD_RET_FAILURE;
> > > + }
> > > +
> > > + ret = efi_install_fdt(fdt);
> > > + if (ret == EFI_INVALID_PARAMETER)
> > > + return CMD_RET_USAGE;
> > > + else if (ret != EFI_SUCCESS)
> > > + return CMD_RET_FAILURE;
> >
> > These lines could be moved into do_efibootmgr.
>
> It will be done in patch#3 when carving out bootmgr specific code.
>
> > Should we move the translations of the return codes into efi_install_fdt?
>
> No, I don't think so. efi_install_fdt() can be called not only from
> the command (bootefi) but also from other library code (at least,
> efi_bootmgr_run() and efi_binary_run()).
>
> -Takahiro Akashi
>
> > Best regards
> >
> > Heinrich
> >
> > > +
> > > + return do_efibootmgr();
> > > }
> > > -#ifdef CONFIG_CMD_BOOTEFI_SELFTEST
> > > - if (!strcmp(argv[1], "selftest"))
> > > +
> > > + if (IS_ENABLED(CONFIG_CMD_BOOTEFI_SELFTEST) &&
> > > + !strcmp(argv[1], "selftest")) {
> > > + /* Initialize EFI drivers */
> > > + ret = efi_init_obj_list();
> > > + if (ret != EFI_SUCCESS) {
> > > + log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
> > > + ret & ~EFI_ERROR_MASK);
> > > + return CMD_RET_FAILURE;
> > > + }
> > > +
> > > + ret = efi_install_fdt(fdt);
> > > + if (ret == EFI_INVALID_PARAMETER)
> > > + return CMD_RET_USAGE;
> > > + else if (ret != EFI_SUCCESS)
> > > + return CMD_RET_FAILURE;
> > > +
> > > return do_efi_selftest();
> > > -#endif
> > > + }
> > >
> > > -#ifdef CONFIG_CMD_BOOTEFI_HELLO
> > > - if (!strcmp(argv[1], "hello")) {
> > > + if (!IS_ENABLED(CONFIG_CMD_BOOTEFI_BINARY))
> > > + return CMD_RET_SUCCESS;
> > > +
> > > + if (IS_ENABLED(CONFIG_CMD_BOOTEFI_HELLO) &&
> > > + !strcmp(argv[1], "hello")) {
> > > image_buf = __efi_helloworld_begin;
> > > size = __efi_helloworld_end - __efi_helloworld_begin;
> > > efi_clear_bootdev();
> > > - } else
> > > -#endif
> > > - {
> > > + } else {
> > > addr = strtoul(argv[1], NULL, 16);
> > > /* Check that a numeric value was passed */
> > > if (!addr)
> > > @@ -675,6 +690,21 @@ static int do_bootefi(struct cmd_tbl *cmdtp, int flag, int argc,
> > > size = image_size;
> > > }
> > > }
> > > +
> > > + /* Initialize EFI drivers */
> > > + ret = efi_init_obj_list();
> > > + if (ret != EFI_SUCCESS) {
> > > + log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
> > > + ret & ~EFI_ERROR_MASK);
> > > + return CMD_RET_FAILURE;
> > > + }
> > > +
> > > + ret = efi_install_fdt(fdt);
> > > + if (ret == EFI_INVALID_PARAMETER)
> > > + return CMD_RET_USAGE;
> > > + else if (ret != EFI_SUCCESS)
> > > + return CMD_RET_FAILURE;
> > > +
> > > ret = efi_run_image(image_buf, size);
> > >
> > > if (ret != EFI_SUCCESS)
> > > diff --git a/include/efi_loader.h b/include/efi_loader.h
> > > index 664dae28f882..44436d346286 100644
> > > --- a/include/efi_loader.h
> > > +++ b/include/efi_loader.h
> > > @@ -879,14 +879,12 @@ efi_status_t __efi_runtime EFIAPI efi_get_time(
> > >
> > > efi_status_t __efi_runtime EFIAPI efi_set_time(struct efi_time *time);
> > >
> > > -#ifdef CONFIG_CMD_BOOTEFI_SELFTEST
> > > /*
> > > * Entry point for the tests of the EFI API.
> > > * It is called by 'bootefi selftest'
> > > */
> > > efi_status_t EFIAPI efi_selftest(efi_handle_t image_handle,
> > > struct efi_system_table *systab);
> > > -#endif
> > >
> > > efi_status_t EFIAPI efi_get_variable(u16 *variable_name,
> > > const efi_guid_t *vendor, u32 *attributes,
> >

Thanks
/Ilias