[PATCH 1/3] efi: Turn boot memmap handling into shared code

[Ard Biesheuvel]

Move the handling of the boot memmap config table from loongarch
specific code to code that is shared between all architectures that
select EFI_GENERIC_STUB (all EFI archs except x86).

This will be used in a subsequent patch to replace the clunky FDT based
passing of the memmap parameters.

Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/loongarch/kernel/efi.c | 10 ++++------
 drivers/firmware/efi/efi.c  |  4 ++++
 include/linux/efi.h         |  3 +++
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/loongarch/kernel/efi.c b/arch/loongarch/kernel/efi.c
index 69dd83f8082f..089378856bab 100644
--- a/arch/loongarch/kernel/efi.c
+++ b/arch/loongarch/kernel/efi.c
@@ -28,12 +28,10 @@
 static unsigned long efi_nr_tables;
 static unsigned long efi_config_table;
 
-static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
 static unsigned long __initdata fdt_pointer = EFI_INVALID_TABLE_ADDR;
 
 static efi_system_table_t *efi_systab;
 static efi_config_table_type_t arch_tables[] __initdata = {
-	{LINUX_EFI_BOOT_MEMMAP_GUID,	&boot_memmap,	"MEMMAP" },
 	{DEVICE_TREE_GUID,		&fdt_pointer,	"FDTPTR" },
 	{},
 };
@@ -132,14 +130,14 @@ void __init efi_init(void)
 	if (IS_ENABLED(CONFIG_EFI_EARLYCON) || IS_ENABLED(CONFIG_SYSFB))
 		init_primary_display();
 
-	if (boot_memmap == EFI_INVALID_TABLE_ADDR)
+	if (efi.boot_memmap == EFI_INVALID_TABLE_ADDR)
 		return;
 
-	tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
+	tbl = early_memremap_ro(efi.boot_memmap, sizeof(*tbl));
 	if (tbl) {
 		struct efi_memory_map_data data;
 
-		data.phys_map		= boot_memmap + sizeof(*tbl);
+		data.phys_map		= efi.boot_memmap + sizeof(*tbl);
 		data.size		= tbl->map_size;
 		data.desc_size		= tbl->desc_size;
 		data.desc_version	= tbl->desc_ver;
@@ -156,7 +154,7 @@ void __init efi_init(void)
 		 * Also, set the EFI_PRESERVE_BS_REGIONS flag to indicate that
 		 * critical boot services code/data regions like this are preserved.
 		 */
-		memblock_reserve((phys_addr_t)boot_memmap, sizeof(*tbl) + data.size);
+		memblock_reserve((phys_addr_t)efi.boot_memmap, sizeof(*tbl) + data.size);
 		set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags);
 
 		early_memunmap(tbl, sizeof(*tbl));
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 0327a39d31fa..d33760d6a527 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -55,6 +55,9 @@ struct efi __read_mostly efi = {
 #ifdef CONFIG_UNACCEPTED_MEMORY
 	.unaccepted		= EFI_INVALID_TABLE_ADDR,
 #endif
+#ifdef CONFIG_EFI_GENERIC_STUB
+	.boot_memmap		= EFI_INVALID_TABLE_ADDR,
+#endif
 };
 EXPORT_SYMBOL(efi);
 
@@ -647,6 +650,7 @@ static const efi_config_table_type_t common_tables[] __initconst = {
 	{LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID,	&efi.unaccepted,	"Unaccepted"	},
 #endif
 #ifdef CONFIG_EFI_GENERIC_STUB
+	{LINUX_EFI_BOOT_MEMMAP_GUID,		&efi.boot_memmap,	"MEMMAP"	},
 	{LINUX_EFI_PRIMARY_DISPLAY_TABLE_GUID,	&primary_display_table			},
 #endif
 	{},
diff --git a/include/linux/efi.h b/include/linux/efi.h
index aa15ff88539b..bc1cd005ca0f 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -650,6 +650,9 @@ extern struct efi {
 	unsigned long			mokvar_table;		/* MOK variable config table */
 	unsigned long			coco_secret;		/* Confidential computing secret table */
 	unsigned long			unaccepted;		/* Unaccepted memory table */
+#ifdef CONFIG_EFI_GENERIC_STUB
+	unsigned long			boot_memmap;		/* The EFI memory map captured by the stub */
+#endif
 
 	efi_get_time_t			*get_time;
 	efi_set_time_t			*set_time;
-- 
2.47.3