x86: introduce init_memory_mapping for 32bit #1

... so can we use mem below max_low_pfn earlier.

this allows us to move several functions more early instead of waiting
to after paging_init.

That includes moving relocate_initrd() earlier in the bootup, and kva
related early setup done in initmem_init. (in followup patches)

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

1 files changed, 2 insertions, 0 deletions

diff --git a/include/asm-x86/page_32.h b/include/asm-x86/page_32.h
index 3810d14051e8..4ae1daba129b 100644
--- a/include/asm-x86/page_32.h
+++ b/include/asm-x86/page_32.h
@@ -93,6 +93,8 @@ extern int sysctl_legacy_va_layout;
 #define MAXMEM                  (-__PAGE_OFFSET - __VMALLOC_RESERVE)
 
 extern void find_low_pfn_range(void);
+extern unsigned long init_memory_mapping(unsigned long start,
+                                         unsigned long end);
 extern void initmem_init(unsigned long, unsigned long);
 extern void zone_sizes_init(void);
 extern void setup_bootmem_allocator(void);