x86: introduce reserve_initrd

Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/kernel/setup_32.c

@@ -336,7 +336,7 @@ void __init reserve_initrd(void)
 		 * in i386_start_kernel
 		 */
 		initrd_start = ramdisk_image + PAGE_OFFSET;
-		initrd_end = initrd_start+ramdisk_size;
+		initrd_end = initrd_start + ramdisk_size;
 		return;
 	}
 
@@ -363,7 +363,7 @@ void __init reserve_initrd(void)
 
 #define MAX_MAP_CHUNK	(NR_FIX_BTMAPS << PAGE_SHIFT)
 
-static void __init relocate_initrd(void)
+static void __init post_reserve_initrd(void)
 {
 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 	u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
@@ -417,7 +417,13 @@ static void __init relocate_initrd(void)
 	/* need to free that, otherwise init highmem will reserve it again */
 	free_early(ramdisk_image, ramdisk_image+ramdisk_size);
 }
-
+#else
+void __init reserve_initrd(void)
+{
+}
+static void __init post_reserve_initrd(void)
+{
+}
 #endif /* CONFIG_BLK_DEV_INITRD */
 
 /*
@@ -632,9 +638,7 @@ void __init setup_arch(char **cmdline_p)
 	 * NOTE: at this point the bootmem allocator is fully available.
 	 */
 
-#ifdef CONFIG_BLK_DEV_INITRD
-	relocate_initrd();
-#endif
+	post_reserve_initrd();
 
 	remapped_pgdat_init();
 	sparse_init();

arch/x86/mm/init_32.c

@@ -597,8 +597,6 @@ void __init zone_sizes_init(void)
 }
 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 
-extern void reserve_initrd(void);
-
 void __init setup_bootmem_allocator(void)
 {
 	int i;
@@ -613,9 +611,9 @@ void __init setup_bootmem_allocator(void)
 	if (bootmap == -1L)
 		panic("Cannot find bootmem map of size %ld\n", bootmap_size);
 	reserve_early(bootmap, bootmap + bootmap_size, "BOOTMAP");
-#ifdef CONFIG_BLK_DEV_INITRD
+
 	reserve_initrd();
-#endif
+
 	bootmap_size = init_bootmem(bootmap >> PAGE_SHIFT, max_low_pfn);
 	printk(KERN_INFO "  mapped low ram: 0 - %08lx\n",
 		 max_pfn_mapped<<PAGE_SHIFT);

include/asm-x86/setup.h

@@ -39,6 +39,8 @@ void reserve_crashkernel(void);
 #include <asm/bootparam.h>
 
 void reserve_standard_io_resources(void);
+void reserve_initrd(void);
+
 
 #ifndef _SETUP