[PATCH v2 0/2] efi/fdt: get_fdt cleanups

[PATCH v2 0/2] efi/fdt: get_fdt cleanups

[Julien Thierry]

Hi,

Here are just some minor cleanups of get_fdt function.

Changes since v1:
- Add a set of brace for the for loop
- Reorganize code as suggested by Joe

[1] https://lkml.org/lkml/2018/10/1/465

Thanks,

Julien

-->

Julien Thierry (2):
  efi/fdt: Indentation fix
  efi/fdt: Simplify get_fdt flow

 drivers/firmware/efi/libstub/fdt.c | 30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

--
1.9.1

[PATCH v2 1/2] efi/fdt: Indentation fix

[Julien Thierry]

Closing bracket seems to end a for statement when it is actually ending
the contained if. Add some brackets to have clear delimitation of each
scope.

No functional change/fix, just fix the indentation.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 drivers/firmware/efi/libstub/fdt.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 8830fa6..8b6696e 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -372,7 +372,7 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
 	tables = (efi_config_table_t *) sys_table->tables;
 	fdt = NULL;
 
-	for (i = 0; i < sys_table->nr_tables; i++)
+	for (i = 0; i < sys_table->nr_tables; i++) {
 		if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
 			fdt = (void *) tables[i].table;
 			if (fdt_check_header(fdt) != 0) {
@@ -381,7 +381,8 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
 			}
 			*fdt_size = fdt_totalsize(fdt);
 			break;
-	 }
+		}
+	}
 
 	return fdt;
 }
-- 
1.9.1

Re: [PATCH v2 1/2] efi/fdt: Indentation fix

[Ard Biesheuvel]

On 29 October 2018 at 11:15, Julien Thierry <julien.thierry@arm.com> wrote:
> Closing bracket seems to end a for statement when it is actually ending
> the contained if. Add some brackets to have clear delimitation of each
> scope.
>
> No functional change/fix, just fix the indentation.
>
> Signed-off-by: Julien Thierry <julien.thierry@arm.com>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  drivers/firmware/efi/libstub/fdt.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
> index 8830fa6..8b6696e 100644
> --- a/drivers/firmware/efi/libstub/fdt.c
> +++ b/drivers/firmware/efi/libstub/fdt.c
> @@ -372,7 +372,7 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
>         tables = (efi_config_table_t *) sys_table->tables;
>         fdt = NULL;
>
> -       for (i = 0; i < sys_table->nr_tables; i++)
> +       for (i = 0; i < sys_table->nr_tables; i++) {
>                 if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
>                         fdt = (void *) tables[i].table;
>                         if (fdt_check_header(fdt) != 0) {
> @@ -381,7 +381,8 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
>                         }
>                         *fdt_size = fdt_totalsize(fdt);
>                         break;
> -        }
> +               }
> +       }
>
>         return fdt;
>  }
> --
> 1.9.1
>


Queued in efi/next

Thanks.

[PATCH v2 2/2] efi/fdt: Simplify get_fdt flow

[Julien Thierry]

Reorganize get_fdt lookup loop, clearly showing that:
- Nothing is done for table entries that do not have fdt_guid
- Once an entry with fdt_guid is found, break out of the loop

No functional changes.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Suggested-by: Joe Perches <joe@perches.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 drivers/firmware/efi/libstub/fdt.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 8b6696e..5b7e2b3 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -366,23 +366,24 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
 {
 	efi_guid_t fdt_guid = DEVICE_TREE_GUID;
 	efi_config_table_t *tables;
-	void *fdt;
 	int i;
 
-	tables = (efi_config_table_t *) sys_table->tables;
-	fdt = NULL;
+	tables = (efi_config_table_t *)sys_table->tables;
 
 	for (i = 0; i < sys_table->nr_tables; i++) {
-		if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
-			fdt = (void *) tables[i].table;
-			if (fdt_check_header(fdt) != 0) {
-				pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
-				return NULL;
-			}
-			*fdt_size = fdt_totalsize(fdt);
-			break;
+		void *fdt;
+
+		if (efi_guidcmp(tables[i].guid, fdt_guid) != 0)
+			continue;
+
+		fdt = (void *) tables[i].table;
+		if (fdt_check_header(fdt) != 0) {
+			pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
+			return NULL;
 		}
+		*fdt_size = fdt_totalsize(fdt);
+		return fdt;
 	}
 
-	return fdt;
+	return NULL;
 }
-- 
1.9.1

Re: [PATCH v2 2/2] efi/fdt: Simplify get_fdt flow

[Ard Biesheuvel]

On 29 October 2018 at 11:15, Julien Thierry <julien.thierry@arm.com> wrote:
> Reorganize get_fdt lookup loop, clearly showing that:
> - Nothing is done for table entries that do not have fdt_guid
> - Once an entry with fdt_guid is found, break out of the loop
>
> No functional changes.
>
> Signed-off-by: Julien Thierry <julien.thierry@arm.com>
> Suggested-by: Joe Perches <joe@perches.com>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  drivers/firmware/efi/libstub/fdt.c | 25 +++++++++++++------------
>  1 file changed, 13 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
> index 8b6696e..5b7e2b3 100644
> --- a/drivers/firmware/efi/libstub/fdt.c
> +++ b/drivers/firmware/efi/libstub/fdt.c
> @@ -366,23 +366,24 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
>  {
>         efi_guid_t fdt_guid = DEVICE_TREE_GUID;
>         efi_config_table_t *tables;
> -       void *fdt;
>         int i;
>
> -       tables = (efi_config_table_t *) sys_table->tables;
> -       fdt = NULL;
> +       tables = (efi_config_table_t *)sys_table->tables;
>
>         for (i = 0; i < sys_table->nr_tables; i++) {
> -               if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
> -                       fdt = (void *) tables[i].table;
> -                       if (fdt_check_header(fdt) != 0) {
> -                               pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
> -                               return NULL;
> -                       }
> -                       *fdt_size = fdt_totalsize(fdt);
> -                       break;
> +               void *fdt;
> +
> +               if (efi_guidcmp(tables[i].guid, fdt_guid) != 0)
> +                       continue;
> +
> +               fdt = (void *) tables[i].table;
> +               if (fdt_check_header(fdt) != 0) {
> +                       pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
> +                       return NULL;
>                 }
> +               *fdt_size = fdt_totalsize(fdt);
> +               return fdt;
>         }
>
> -       return fdt;
> +       return NULL;
>  }
> --
> 1.9.1
>

Queued in efi/next

Thanks.