[PATCH 03/11] efi/fdt: Simplify get_fdt flow

From: Ard Biesheuvel
Date: Thu Nov 29 2018 - 12:13:01 EST


From: Julien Thierry <julien.thierry@xxxxxxx>

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.

Suggested-by: Joe Perches <joe@xxxxxxxxxxx>
Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@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;
}
--
2.19.1