/arch/x86/include/asm/pgtable_32_types.h

 1#ifndef _ASM_X86_PGTABLE_32_DEFS_H
 2#define _ASM_X86_PGTABLE_32_DEFS_H
 3
 4/*
 5 * The Linux x86 paging architecture is 'compile-time dual-mode', it
 6 * implements both the traditional 2-level x86 page tables and the
 7 * newer 3-level PAE-mode page tables.
 8 */
 9#ifdef CONFIG_X86_PAE
10# include <asm/pgtable-3level_types.h>
11# define PMD_SIZE	(1UL << PMD_SHIFT)
12# define PMD_MASK	(~(PMD_SIZE - 1))
13#else
14# include <asm/pgtable-2level_types.h>
15#endif
16
17#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
18#define PGDIR_MASK	(~(PGDIR_SIZE - 1))
19
20/* Just any arbitrary offset to the start of the vmalloc VM area: the
21 * current 8MB value just means that there will be a 8MB "hole" after the
22 * physical memory until the kernel virtual memory starts.  That means that
23 * any out-of-bounds memory accesses will hopefully be caught.
24 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
25 * area for the same reason. ;)
26 */
27#define VMALLOC_OFFSET	(8 * 1024 * 1024)
28
29#ifndef __ASSEMBLY__
30extern bool __vmalloc_start_set; /* set once high_memory is set */
31#endif
32
33#define VMALLOC_START	((unsigned long)high_memory + VMALLOC_OFFSET)
34#ifdef CONFIG_X86_PAE
35#define LAST_PKMAP 512
36#else
37#define LAST_PKMAP 1024
38#endif
39
40#define PKMAP_BASE ((FIXADDR_BOOT_START - PAGE_SIZE * (LAST_PKMAP + 1))	\
41		    & PMD_MASK)
42
43#ifdef CONFIG_HIGHMEM
44# define VMALLOC_END	(PKMAP_BASE - 2 * PAGE_SIZE)
45#else
46# define VMALLOC_END	(FIXADDR_START - 2 * PAGE_SIZE)
47#endif
48
49#define MODULES_VADDR	VMALLOC_START
50#define MODULES_END	VMALLOC_END
51#define MODULES_LEN	(MODULES_VADDR - MODULES_END)
52
53#define MAXMEM	(VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE)
54
55#endif /* _ASM_X86_PGTABLE_32_DEFS_H */