| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _ASM_GENERIC_SECTIONS_H_ |
| 3 | #define _ASM_GENERIC_SECTIONS_H_ |
| 4 | |
| 5 | /* References to section boundaries */ |
| 6 | |
| 7 | #include <linux/compiler.h> |
| 8 | #include <linux/types.h> |
| 9 | |
| 10 | /* |
| 11 | * Usage guidelines: |
| 12 | * _text, _data: architecture specific, don't use them in arch-independent code |
| 13 | * [_stext, _etext]: contains .text.* sections, may also contain .rodata.* |
| 14 | * and/or .init.* sections |
| 15 | * [_sdata, _edata]: contains .data.* sections, may also contain .rodata.* |
| 16 | * and/or .init.* sections. |
| 17 | * [__start_rodata, __end_rodata]: contains .rodata.* sections |
| 18 | * [__start_ro_after_init, __end_ro_after_init]: |
| 19 | * contains .data..ro_after_init section |
| 20 | * [__init_begin, __init_end]: contains .init.* sections, but .init.text.* |
| 21 | * may be out of this range on some architectures. |
| 22 | * [_sinittext, _einittext]: contains .init.text.* sections |
| 23 | * [__bss_start, __bss_stop]: contains BSS sections |
| 24 | * |
| 25 | * Following global variables are optional and may be unavailable on some |
| 26 | * architectures and/or kernel configurations. |
| 27 | * _text, _data |
| 28 | * __kprobes_text_start, __kprobes_text_end |
| 29 | * __entry_text_start, __entry_text_end |
| 30 | * __ctors_start, __ctors_end |
| 31 | * __irqentry_text_start, __irqentry_text_end |
| 32 | * __softirqentry_text_start, __softirqentry_text_end |
| 33 | */ |
| 34 | extern char _text[], _stext[], _etext[]; |
| 35 | extern char _data[], _sdata[], _edata[]; |
| 36 | extern char __bss_start[], __bss_stop[]; |
| 37 | extern char __init_begin[], __init_end[]; |
| 38 | extern char _sinittext[], _einittext[]; |
| 39 | extern char __start_ro_after_init[], __end_ro_after_init[]; |
| 40 | extern char _end[]; |
| 41 | extern char __per_cpu_load[], __per_cpu_start[], __per_cpu_end[]; |
| 42 | extern char __kprobes_text_start[], __kprobes_text_end[]; |
| 43 | extern char __entry_text_start[], __entry_text_end[]; |
| 44 | extern char __start_rodata[], __end_rodata[]; |
| 45 | extern char __irqentry_text_start[], __irqentry_text_end[]; |
| 46 | extern char __softirqentry_text_start[], __softirqentry_text_end[]; |
| 47 | |
| 48 | /* Start and end of .ctors section - used for constructor calls. */ |
| 49 | extern char __ctors_start[], __ctors_end[]; |
| 50 | |
| 51 | extern __visible const void __nosave_begin, __nosave_end; |
| 52 | |
| 53 | /* function descriptor handling (if any). Override |
| 54 | * in asm/sections.h */ |
| 55 | #ifndef dereference_function_descriptor |
| 56 | #define dereference_function_descriptor(p) (p) |
| 57 | #endif |
| 58 | |
| 59 | /* random extra sections (if any). Override |
| 60 | * in asm/sections.h */ |
| 61 | #ifndef arch_is_kernel_text |
| 62 | static inline int arch_is_kernel_text(unsigned long addr) |
| 63 | { |
| 64 | return 0; |
| 65 | } |
| 66 | #endif |
| 67 | |
| 68 | #ifndef arch_is_kernel_data |
| 69 | static inline int arch_is_kernel_data(unsigned long addr) |
| 70 | { |
| 71 | return 0; |
| 72 | } |
| 73 | #endif |
| 74 | |
| 75 | /** |
| 76 | * memory_contains - checks if an object is contained within a memory region |
| 77 | * @begin: virtual address of the beginning of the memory region |
| 78 | * @end: virtual address of the end of the memory region |
| 79 | * @virt: virtual address of the memory object |
| 80 | * @size: size of the memory object |
| 81 | * |
| 82 | * Returns: true if the object specified by @virt and @size is entirely |
| 83 | * contained within the memory region defined by @begin and @end, false |
| 84 | * otherwise. |
| 85 | */ |
| 86 | static inline bool memory_contains(void *begin, void *end, void *virt, |
| 87 | size_t size) |
| 88 | { |
| 89 | return virt >= begin && virt + size <= end; |
| 90 | } |
| 91 | |
| 92 | /** |
| 93 | * memory_intersects - checks if the region occupied by an object intersects |
| 94 | * with another memory region |
| 95 | * @begin: virtual address of the beginning of the memory regien |
| 96 | * @end: virtual address of the end of the memory region |
| 97 | * @virt: virtual address of the memory object |
| 98 | * @size: size of the memory object |
| 99 | * |
| 100 | * Returns: true if an object's memory region, specified by @virt and @size, |
| 101 | * intersects with the region specified by @begin and @end, false otherwise. |
| 102 | */ |
| 103 | static inline bool memory_intersects(void *begin, void *end, void *virt, |
| 104 | size_t size) |
| 105 | { |
| 106 | void *vend = virt + size; |
| 107 | |
| 108 | return (virt >= begin && virt < end) || (vend >= begin && vend < end); |
| 109 | } |
| 110 | |
| 111 | /** |
| 112 | * init_section_contains - checks if an object is contained within the init |
| 113 | * section |
| 114 | * @virt: virtual address of the memory object |
| 115 | * @size: size of the memory object |
| 116 | * |
| 117 | * Returns: true if the object specified by @virt and @size is entirely |
| 118 | * contained within the init section, false otherwise. |
| 119 | */ |
| 120 | static inline bool init_section_contains(void *virt, size_t size) |
| 121 | { |
| 122 | return memory_contains(__init_begin, __init_end, virt, size); |
| 123 | } |
| 124 | |
| 125 | /** |
| 126 | * init_section_intersects - checks if the region occupied by an object |
| 127 | * intersects with the init section |
| 128 | * @virt: virtual address of the memory object |
| 129 | * @size: size of the memory object |
| 130 | * |
| 131 | * Returns: true if an object's memory region, specified by @virt and @size, |
| 132 | * intersects with the init section, false otherwise. |
| 133 | */ |
| 134 | static inline bool init_section_intersects(void *virt, size_t size) |
| 135 | { |
| 136 | return memory_intersects(__init_begin, __init_end, virt, size); |
| 137 | } |
| 138 | |
| 139 | #endif /* _ASM_GENERIC_SECTIONS_H_ */ |