Commit 7d1116a9 authored by Andi Kleen's avatar Andi Kleen Committed by Ingo Molnar
Browse files

x86: implement true end_pfn_mapped for 32bit 



Even on 32bit 2MB pages can map more memory than is in the true
max_low_pfn if end_pfn is not highmem and not aligned to 2MB.
Add a end_pfn_map similar to x86-64 that accounts for this
fact. This is important for code that really needs to know about
all mapping aliases.

Signed-off-by: default avatarAndi Kleen <ak@suse.de>
Cc: andreas.herrmann3@amd.com
Cc: mingo@elte.hu
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 41bd4eac

arch/x86/mm/init_32.c

+4 −0
Original line number Diff line number Diff line
@@ -51,6 +51,8 @@ 


unsigned int __VMALLOC_RESERVE = 128 << 20;



unsigned long end_pfn_map;



DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

unsigned long highstart_pfn, highend_pfn;
@@ -194,6 +196,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) 
				set_pmd(pmd, pfn_pmd(pfn, prot));



				pfn += PTRS_PER_PTE;

				end_pfn_map = pfn;

				continue;

			}

			pte = one_page_table_init(pmd);
@@ -208,6 +211,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) 


				set_pte(pte, pfn_pte(pfn, prot));

			}

			end_pfn_map = pfn;

		}

	}

}

include/asm-x86/page.h

+3 −1
Original line number Diff line number Diff line
@@ -36,7 +36,7 @@ 
#define max_pfn_mapped		end_pfn_map

#else

#include <asm/page_32.h>

#define max_pfn_mapped		max_low_pfn

#define max_pfn_mapped		end_pfn_map

#endif	/* CONFIG_X86_64 */



#define PAGE_OFFSET		((unsigned long)__PAGE_OFFSET)
@@ -50,6 +50,8 @@ 


extern int page_is_ram(unsigned long pagenr);



extern unsigned long end_pfn_map;



struct page;



static inline void clear_user_page(void *page, unsigned long vaddr,

include/asm-x86/page_64.h

+0 −1
Original line number Diff line number Diff line
@@ -59,7 +59,6 @@ void clear_page(void *page); 
void copy_page(void *to, void *from);



extern unsigned long end_pfn;

extern unsigned long end_pfn_map;

extern unsigned long phys_base;



extern unsigned long __phys_addr(unsigned long);