[U-Boot] [PATCH v6 3/7] cmd: efidebug: add devices command

[AKASHI Takahiro]

On Tue, Feb 19, 2019 at 08:46:52PM +0100, Heinrich Schuchardt wrote:
> On 1/24/19 12:04 PM, AKASHI Takahiro wrote:
> > "devices" command prints all the uefi variables on the system.
> > 
> > => efi devices
> > Scanning disk ahci_scsi.id0lun0...
> > Scanning disk ahci_scsi.id1lun0...
> > Found 4 disks
> > Device           Device Path
> > ================ ====================
> > 000000007ef07ea0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
> > 000000007ef00c10 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(0,0)
> > 000000007ef00dd0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(1,0)
> > 000000007ef07be0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(1,0)/HD(1,MBR,0x086246ba,0x800,0x40000)
> > 000000007ef07510 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(1,0)/HD(2,MBR,0x086246ba,0x40800,0x3f800)
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> > ---
> >  cmd/efidebug.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 101 insertions(+), 1 deletion(-)
> > 
> > diff --git a/cmd/efidebug.c b/cmd/efidebug.c
> > index d836576cf6e0..8a7f775b117a 100644
> > --- a/cmd/efidebug.c
> > +++ b/cmd/efidebug.c
> > @@ -15,6 +15,102 @@
> >  #include <search.h>
> >  #include <linux/ctype.h>
> >  
> > +#define BS systab.boottime
> > +
> 
> Please, add Sphinx style descriptions to all functions, their
> parameters, and return values.

Sure, but please clearify what you mean by "all."
Do you expect descriptions for exactly all the functions,
even for some helper functions of a few lines of code?

> Why do you need this function? Can't you call LocateHandleBuffer() which
> takes care of the allocation of the buffer?
> 
> > +static int efi_get_handles_by_proto(efi_guid_t *guid, efi_handle_t **handlesp,
> > +				    int *num)

Right. I will use locate_handle_buffer here.
But why does UEFI spec define functionally-duplicated functions,
LocateHandle() and LocateHandleBuffer()?

> > +{
> > +	efi_handle_t *handles = NULL;
> > +	efi_uintn_t size = 0;
> > +	efi_status_t ret;
> > +
> > +	if (guid) {
> > +		ret = BS->locate_handle(BY_PROTOCOL, guid, NULL, &size,
> > +					handles);
> 
> This will not work on i386. Please, always use EFI_CALL when invoking a
> function which calls EFI_ENTRY().

OK, but let me make sure.
We don't have to use EFI_CALL() for any of (internal) efi_xxx() functions,
say, efi_add_protocol(). Right?

> > +		if (ret == EFI_BUFFER_TOO_SMALL) {
> > +			handles = calloc(1, size);
> > +			if (!handles)
> > +				return -1;
> > +
> > +			ret = BS->locate_handle(BY_PROTOCOL, guid, NULL, &size,
> > +						handles);
> > +		}
> > +		if (ret != EFI_SUCCESS) {
> > +			free(handles);
> 
> The handles are not allocated by malloc(). Use FreePool() here.

Will take care of that along with the change above.

-Takahiro Akashi


> > +			return -1;
> > +		}
> > +	} else {
> > +		ret = BS->locate_handle(ALL_HANDLES, NULL, NULL, &size, NULL);
> > +		if (ret == EFI_BUFFER_TOO_SMALL) {
> > +			handles = calloc(1, size);
> > +			if (!handles)
> > +				return -1;
> > +
> > +			ret = BS->locate_handle(ALL_HANDLES, NULL, NULL, &size,
> > +						handles);
> > +		}
> > +		if (ret != EFI_SUCCESS) {
> > +			free(handles);
> 
> Same here.
> 
> > +			return -1;
> > +		}
> > +	}
> > +
> > +	*handlesp = handles;
> > +	*num = size / sizeof(efi_handle_t);
> > +
> > +	return 0;
> > +}
> > +
> > +static int efi_get_device_handle_info(efi_handle_t handle, u16 **dev_path_text)
> > +{
> > +	struct efi_device_path *dp;
> > +	efi_status_t ret;
> > +
> > +	ret = BS->open_protocol(handle, &efi_guid_device_path,
> > +				(void **)&dp, NULL /* FIXME */, NULL,
> > +				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> > +	if (ret == EFI_SUCCESS) {
> > +		*dev_path_text = efi_dp_str(dp);
> > +		return 0;
> > +	} else {
> > +		return -1;
> > +	}
> > +}
> > +
> > +#define EFI_HANDLE_WIDTH ((int)sizeof(efi_handle_t) * 2)
> > +
> > +static const char spc[] = "                ";
> > +static const char sep[] = "================";
> > +
> > +static int do_efi_show_devices(cmd_tbl_t *cmdtp, int flag,
> > +			       int argc, char * const argv[])
> > +{
> > +	efi_handle_t *handles;
> > +	u16 *dev_path_text;
> > +	int num, i;
> > +
> > +	handles = NULL;
> > +	num = 0;
> > +	if (efi_get_handles_by_proto(NULL, &handles, &num))
> > +		return CMD_RET_FAILURE;
> > +
> > +	if (!num)
> > +		return CMD_RET_SUCCESS;
> > +
> > +	printf("Device%.*s Device Path\n", EFI_HANDLE_WIDTH - 6, spc);
> > +	printf("%.*s ====================\n", EFI_HANDLE_WIDTH, sep);
> > +	for (i = 0; i < num; i++) {
> > +		if (!efi_get_device_handle_info(handles[i], &dev_path_text)) {
> > +			printf("%p %ls\n", handles[i], dev_path_text);
> > +			efi_free_pool(dev_path_text);
> > +		}
> > +	}
> > +
> > +	free(handles);
> 
> FreePool()!
> 
> Best regards
> 
> Heinrich
> 
> > +
> > +	return CMD_RET_SUCCESS;
> > +}
> > +
> >  static int do_efi_boot_add(cmd_tbl_t *cmdtp, int flag,
> >  			   int argc, char * const argv[])
> >  {
> > @@ -406,6 +502,8 @@ static int do_efi_boot_opt(cmd_tbl_t *cmdtp, int flag,
> >  
> >  static cmd_tbl_t cmd_efidebug_sub[] = {
> >  	U_BOOT_CMD_MKENT(boot, CONFIG_SYS_MAXARGS, 1, do_efi_boot_opt, "", ""),
> > +	U_BOOT_CMD_MKENT(devices, CONFIG_SYS_MAXARGS, 1, do_efi_show_devices,
> > +			 "", ""),
> >  };
> >  
> >  /* Interpreter command to configure UEFI environment */
> > @@ -451,7 +549,9 @@ static char efidebug_help_text[] =
> >  	"  - set UEFI BootNext variable\n"
> >  	"efidebug boot order [<bootid#1> [<bootid#2> [<bootid#3> [...]]]]\n"
> >  	"  - set/show UEFI boot order\n"
> > -	"\n";
> > +	"\n"
> > +	"efidebug devices\n"
> > +	"  - show uefi devices\n";
> >  #endif
> >  
> >  U_BOOT_CMD(
> > 
>