page_64_types.h

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _ASM_X86_PAGE_64_DEFS_H
 3#define _ASM_X86_PAGE_64_DEFS_H
 4
 5#ifndef __ASSEMBLER__
 6#include <asm/kaslr.h>
 7#endif
 8
 9#ifdef CONFIG_KASAN
10#define KASAN_STACK_ORDER 1
11#else
12#define KASAN_STACK_ORDER 0
13#endif
14
15#define THREAD_SIZE_ORDER	(2 + KASAN_STACK_ORDER)
16#define THREAD_SIZE  (PAGE_SIZE << THREAD_SIZE_ORDER)
17
18#define EXCEPTION_STACK_ORDER (1 + KASAN_STACK_ORDER)
19#define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER)
20
21#define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER)
22#define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER)
23
24/*
25 * The index for the tss.ist[] array. The hardware limit is 7 entries.
26 */
27#define	IST_INDEX_DF		0
28#define	IST_INDEX_NMI		1
29#define	IST_INDEX_DB		2
30#define	IST_INDEX_MCE		3
31#define	IST_INDEX_VC		4
32
33/*
34 * Set __PAGE_OFFSET to the most negative possible address +
35 * PGDIR_SIZE*17 (pgd slot 273).
36 *
37 * The gap is to allow a space for LDT remap for PTI (1 pgd slot) and space for
38 * a hypervisor (16 slots). Choosing 16 slots for a hypervisor is arbitrary,
39 * but it's what Xen requires.
40 */
41#define __PAGE_OFFSET_BASE_L5	_AC(0xff11000000000000, UL)
42#define __PAGE_OFFSET_BASE_L4	_AC(0xffff888000000000, UL)
43
44#define __PAGE_OFFSET           page_offset_base
45
46#define __START_KERNEL_map	_AC(0xffffffff80000000, UL)
47
48/* See Documentation/arch/x86/x86_64/mm.rst for a description of the memory map. */
49
50#define __PHYSICAL_MASK_SHIFT	52
51#define __VIRTUAL_MASK_SHIFT	(pgtable_l5_enabled() ? 56 : 47)
52
53#define TASK_SIZE_MAX		task_size_max()
54#define DEFAULT_MAP_WINDOW	((1UL << 47) - PAGE_SIZE)
55
56/* This decides where the kernel will search for a free chunk of vm
57 * space during mmap's.
58 */
59#define IA32_PAGE_OFFSET	((current->personality & ADDR_LIMIT_3GB) ? \
60					0xc0000000 : 0xFFFFe000)
61
62#define TASK_SIZE_LOW		(test_thread_flag(TIF_ADDR32) ? \
63					IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW)
64#define TASK_SIZE		(test_thread_flag(TIF_ADDR32) ? \
65					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
66#define TASK_SIZE_OF(child)	((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
67					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
68
69#define STACK_TOP		TASK_SIZE_LOW
70#define STACK_TOP_MAX		TASK_SIZE_MAX
71
72/*
73 * In spite of the name, KERNEL_IMAGE_SIZE is a limit on the maximum virtual
74 * address for the kernel image, rather than the limit on the size itself.
75 * This can be at most 1 GiB, due to the fixmap living in the next 1 GiB (see
76 * level2_kernel_pgt in arch/x86/kernel/head_64.S).
77 *
78 * On KASLR use 1 GiB by default, leaving 1 GiB for modules once the
79 * page tables are fully set up.
80 *
81 * If KASLR is disabled we can shrink it to 0.5 GiB and increase the size
82 * of the modules area to 1.5 GiB.
83 */
84#ifdef CONFIG_RANDOMIZE_BASE
85#define KERNEL_IMAGE_SIZE	(1024 * 1024 * 1024)
86#else
87#define KERNEL_IMAGE_SIZE	(512 * 1024 * 1024)
88#endif
89
90#endif /* _ASM_X86_PAGE_64_DEFS_H */