[tip:efi/core] efi/fdt: Simplify the get_fdt() flow

[tip-bot for Julien Thierry]

Commit-ID:  8c25db0a5a67986106aa3da7ce165ff961aa7847
Gitweb:     https://git.kernel.org/tip/8c25db0a5a67986106aa3da7ce165ff961aa7847
Author:     Julien Thierry <julien.thierry@xxxxxxx>
AuthorDate: Thu, 29 Nov 2018 18:12:22 +0100
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Fri, 30 Nov 2018 09:10:30 +0100

efi/fdt: Simplify the get_fdt() flow

Reorganize the 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.

Suggested-by: Joe Perches <joe@xxxxxxxxxxx>
Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx>
Cc: Bhupesh Sharma <bhsharma@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: Eric Snowberg <eric.snowberg@xxxxxxxxxx>
Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
Cc: Jon Hunter <jonathanh@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Nathan Chancellor <natechancellor@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@xxxxxxxxx>
Cc: Sedat Dilek <sedat.dilek@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: YiFei Zhu <zhuyifei1999@xxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20181129171230.18699-4-ard.biesheuvel@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 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 a3614f9b5f75..0dc7b4987cc2 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -370,23 +370,24 @@ 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;
 }