arch/x86/include/asm/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 __ASSEMBLY__
   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 #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
  45 #define __PAGE_OFFSET           page_offset_base
  46 #else
  47 #define __PAGE_OFFSET           __PAGE_OFFSET_BASE_L4
  48 #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */
  49
  50 #define __START_KERNEL_map      _AC(0xffffffff80000000, UL)
  51
  52 /* See Documentation/x86/x86_64/mm.rst for a description of the memory map. */
  53
  54 #define __PHYSICAL_MASK_SHIFT   52
  55
  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> */
  59 #else
  60 #define __VIRTUAL_MASK_SHIFT    47
  61 #define task_size_max()         ((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE)
  62 #endif
  63
  64 #define TASK_SIZE_MAX           task_size_max()
  65 #define DEFAULT_MAP_WINDOW      ((1UL << 47) - PAGE_SIZE)
  66
  67 /* This decides where the kernel will search for a free chunk of vm
  68  * space during mmap's.
  69  */
  70 #define IA32_PAGE_OFFSET        ((current->personality & ADDR_LIMIT_3GB) ? \
  71                                         0xc0000000 : 0xFFFFe000)
  72
  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)
  79
  80 #define STACK_TOP               TASK_SIZE_LOW
  81 #define STACK_TOP_MAX           TASK_SIZE_MAX
  82
  83 /*
  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).
  88  *
  89  * On KASLR use 1 GiB by default, leaving 1 GiB for modules once the
  90  * page tables are fully set up.
  91  *
  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.
  94  */
  95 #ifdef CONFIG_RANDOMIZE_BASE
  96 #define KERNEL_IMAGE_SIZE       (1024 * 1024 * 1024)
  97 #else
  98 #define KERNEL_IMAGE_SIZE       (512 * 1024 * 1024)
  99 #endif
 100
 101 #endif /* _ASM_X86_PAGE_64_DEFS_H */