x86: fixes some bugs about EFI memory map handling

This patch fixes some bugs of EFI memory handing code.

- On x86_64, it is possible that EFI memory map can not be mapped via
  identity map, so efi_map_memmap is removed, just use early_ioremap.

- On i386, the EFI memory map mapping take effect cross paging_init,
  so it is not necessary to use efi_map_memmap.

- EFI memory map is unmapped in efi_enter_virtual_mode to avoid
  early_ioremap leak.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/efi.c

@@ -474,6 +474,8 @@ void __init efi_enter_virtual_mode(void)
 	efi.reset_system = virt_efi_reset_system;
 	efi.set_virtual_address_map = virt_efi_set_virtual_address_map;
 	runtime_code_page_mkexec();
+	early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
+	memmap.map = NULL;
 }
 
 /*

arch/x86/kernel/efi_32.c

@@ -109,18 +109,3 @@ void efi_call_phys_epilog(void)
 
 	local_irq_restore(efi_rt_eflags);
 }
-
-/*
- * We need to map the EFI memory map again after paging_init().
- */
-void __init efi_map_memmap(void)
-{
-	memmap.map = NULL;
-
-	memmap.map = early_ioremap((unsigned long) memmap.phys_map,
-			(memmap.nr_map * memmap.desc_size));
-	if (memmap.map == NULL)
-		printk(KERN_ERR "Could not remap the EFI memmap!\n");
-
-	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
-}

arch/x86/kernel/efi_64.c

@@ -103,15 +103,6 @@ void __init efi_call_phys_epilog(void)
 	local_irq_restore(efi_flags);
 }
 
-/*
- * We need to map the EFI memory map again after init_memory_mapping().
- */
-void __init efi_map_memmap(void)
-{
-	memmap.map = __va(memmap.phys_map);
-	memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
-}
-
 void __init efi_reserve_bootmem(void)
 {
 	reserve_bootmem_generic((unsigned long)memmap.phys_map,

arch/x86/kernel/setup_32.c

@@ -808,8 +808,6 @@ void __init setup_arch(char **cmdline_p)
 #ifdef CONFIG_X86_GENERICARCH
 	generic_apic_probe();
 #endif
-	if (efi_enabled)
-		efi_map_memmap();
 
 #ifdef CONFIG_ACPI
 	/*

arch/x86/kernel/setup_64.c

@@ -378,10 +378,8 @@ void __init setup_arch(char **cmdline_p)
        acpi_reserve_bootmem();
 #endif
 
-	if (efi_enabled) {
-		efi_map_memmap();
+	if (efi_enabled)
 		efi_reserve_bootmem();
-	}
 
        /*
 	* Find and reserve possible boot-time SMP configuration: