1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PAGE_64_DEFS_H
3 #define _ASM_X86_PAGE_64_DEFS_H
10 #define KASAN_STACK_ORDER 1
12 #define KASAN_STACK_ORDER 0
15 #define THREAD_SIZE_ORDER (2 + KASAN_STACK_ORDER)
16 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
18 #define EXCEPTION_STACK_ORDER (1 + KASAN_STACK_ORDER)
19 #define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER)
21 #define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER)
22 #define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER)
25 * The index for the tss.ist[] array. The hardware limit is 7 entries.
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
34 * Set __PAGE_OFFSET to the most negative possible address +
35 * PGDIR_SIZE*17 (pgd slot 273).
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.
41 #define __PAGE_OFFSET_BASE_L5 _AC(0xff11000000000000, UL)
42 #define __PAGE_OFFSET_BASE_L4 _AC(0xffff888000000000, UL)
44 #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
45 #define __PAGE_OFFSET page_offset_base
47 #define __PAGE_OFFSET __PAGE_OFFSET_BASE_L4
48 #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */
50 #define __START_KERNEL_map _AC(0xffffffff80000000, UL)
52 /* See Documentation/arch/x86/x86_64/mm.rst for a description of the memory map. */
54 #define __PHYSICAL_MASK_SHIFT 52
56 #ifdef CONFIG_X86_5LEVEL
57 #define __VIRTUAL_MASK_SHIFT (pgtable_l5_enabled() ? 56 : 47)
58 /* See task_size_max() in <asm/page_64.h> */
60 #define __VIRTUAL_MASK_SHIFT 47
61 #define task_size_max() ((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE)
64 #define TASK_SIZE_MAX task_size_max()
65 #define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE)
67 /* This decides where the kernel will search for a free chunk of vm
68 * space during mmap's.
70 #define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \
71 0xc0000000 : 0xFFFFe000)
73 #define TASK_SIZE_LOW (test_thread_flag(TIF_ADDR32) ? \
74 IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW)
75 #define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \
76 IA32_PAGE_OFFSET : TASK_SIZE_MAX)
77 #define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
78 IA32_PAGE_OFFSET : TASK_SIZE_MAX)
80 #define STACK_TOP TASK_SIZE_LOW
81 #define STACK_TOP_MAX TASK_SIZE_MAX
84 * In spite of the name, KERNEL_IMAGE_SIZE is a limit on the maximum virtual
85 * address for the kernel image, rather than the limit on the size itself.
86 * This can be at most 1 GiB, due to the fixmap living in the next 1 GiB (see
87 * level2_kernel_pgt in arch/x86/kernel/head_64.S).
89 * On KASLR use 1 GiB by default, leaving 1 GiB for modules once the
90 * page tables are fully set up.
92 * If KASLR is disabled we can shrink it to 0.5 GiB and increase the size
93 * of the modules area to 1.5 GiB.
95 #ifdef CONFIG_RANDOMIZE_BASE
96 #define KERNEL_IMAGE_SIZE (1024 * 1024 * 1024)
98 #define KERNEL_IMAGE_SIZE (512 * 1024 * 1024)
101 #endif /* _ASM_X86_PAGE_64_DEFS_H */