efi: Iterate over efi.memmap in for_each_efi_memory_desc()

Most of the users of for_each_efi_memory_desc() are equally happy
iterating over the EFI memory map in efi.memmap instead of 'memmap',
since the former is usually a pointer to the latter.

For those users that want to specify an EFI memory map other than
efi.memmap, that can be done using for_each_efi_memory_desc_in_map().
One such example is in the libstub code where the firmware is queried
directly for the memory map, it gets iterated over, and then freed.

This change goes part of the way toward deleting the global 'memmap'
variable, which is not universally available on all architectures
(notably IA64) and is rather poorly named.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-7-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 3 insertions, 7 deletions

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 49e4dd4a1f58..6e7242be1c87 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -55,14 +55,12 @@ struct efi_scratch efi_scratch;
 static void __init early_code_mapping_set_exec(int executable)
 {
 	efi_memory_desc_t *md;
-	void *p;
 
 	if (!(__supported_pte_mask & _PAGE_NX))
 		return;
 
 	/* Make EFI service code area executable */
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
-		md = p;
+	for_each_efi_memory_desc(md) {
 		if (md->type == EFI_RUNTIME_SERVICES_CODE ||
 		    md->type == EFI_BOOT_SERVICES_CODE)
 			efi_set_executable(md, executable);
@@ -253,7 +251,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 	 * Map all of RAM so that we can access arguments in the 1:1
 	 * mapping when making EFI runtime calls.
 	 */
-	for_each_efi_memory_desc(&memmap, md) {
+	for_each_efi_memory_desc(md) {
 		if (md->type != EFI_CONVENTIONAL_MEMORY &&
 		    md->type != EFI_LOADER_DATA &&
 		    md->type != EFI_LOADER_CODE)
@@ -398,7 +396,6 @@ void __init efi_runtime_update_mappings(void)
 	unsigned long pfn;
 	pgd_t *pgd = efi_pgd;
 	efi_memory_desc_t *md;
-	void *p;
 
 	if (efi_enabled(EFI_OLD_MEMMAP)) {
 		if (__supported_pte_mask & _PAGE_NX)
@@ -409,9 +406,8 @@ void __init efi_runtime_update_mappings(void)
 	if (!efi_enabled(EFI_NX_PE_DATA))
 		return;
 
-	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+	for_each_efi_memory_desc(md) {
 		unsigned long pf = 0;
-		md = p;
 
 		if (!(md->attribute & EFI_MEMORY_RUNTIME))
 			continue;