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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 : : * __start_opd, __end_opd
34 : : */
35 : : extern char _text[], _stext[], _etext[];
36 : : extern char _data[], _sdata[], _edata[];
37 : : extern char __bss_start[], __bss_stop[];
38 : : extern char __init_begin[], __init_end[];
39 : : extern char _sinittext[], _einittext[];
40 : : extern char __start_ro_after_init[], __end_ro_after_init[];
41 : : extern char _end[];
42 : : extern char __per_cpu_load[], __per_cpu_start[], __per_cpu_end[];
43 : : extern char __kprobes_text_start[], __kprobes_text_end[];
44 : : extern char __entry_text_start[], __entry_text_end[];
45 : : extern char __start_rodata[], __end_rodata[];
46 : : extern char __irqentry_text_start[], __irqentry_text_end[];
47 : : extern char __softirqentry_text_start[], __softirqentry_text_end[];
48 : : extern char __start_once[], __end_once[];
49 : :
50 : : /* Start and end of .ctors section - used for constructor calls. */
51 : : extern char __ctors_start[], __ctors_end[];
52 : :
53 : : /* Start and end of .opd section - used for function descriptors. */
54 : : extern char __start_opd[], __end_opd[];
55 : :
56 : : extern __visible const void __nosave_begin, __nosave_end;
57 : :
58 : : /* Function descriptor handling (if any). Override in asm/sections.h */
59 : : #ifndef dereference_function_descriptor
60 : : #define dereference_function_descriptor(p) (p)
61 : : #define dereference_kernel_function_descriptor(p) (p)
62 : : #endif
63 : :
64 : : /* random extra sections (if any). Override
65 : : * in asm/sections.h */
66 : : #ifndef arch_is_kernel_text
67 : : static inline int arch_is_kernel_text(unsigned long addr)
68 : : {
69 : : return 0;
70 : : }
71 : : #endif
72 : :
73 : : #ifndef arch_is_kernel_data
74 : : static inline int arch_is_kernel_data(unsigned long addr)
75 : : {
76 : : return 0;
77 : : }
78 : : #endif
79 : :
80 : : /*
81 : : * Check if an address is part of freed initmem. This is needed on architectures
82 : : * with virt == phys kernel mapping, for code that wants to check if an address
83 : : * is part of a static object within [_stext, _end]. After initmem is freed,
84 : : * memory can be allocated from it, and such allocations would then have
85 : : * addresses within the range [_stext, _end].
86 : : */
87 : : #ifndef arch_is_kernel_initmem_freed
88 : : static inline int arch_is_kernel_initmem_freed(unsigned long addr)
89 : : {
90 : : return 0;
91 : : }
92 : : #endif
93 : :
94 : : /**
95 : : * memory_contains - checks if an object is contained within a memory region
96 : : * @begin: virtual address of the beginning of the memory region
97 : : * @end: virtual address of the end of the memory region
98 : : * @virt: virtual address of the memory object
99 : : * @size: size of the memory object
100 : : *
101 : : * Returns: true if the object specified by @virt and @size is entirely
102 : : * contained within the memory region defined by @begin and @end, false
103 : : * otherwise.
104 : : */
105 : : static inline bool memory_contains(void *begin, void *end, void *virt,
106 : : size_t size)
107 : : {
108 [ + + - + : 329751 : return virt >= begin && virt + size <= end;
# # # # #
# # # # #
# # # # #
# ]
109 : : }
110 : :
111 : : /**
112 : : * memory_intersects - checks if the region occupied by an object intersects
113 : : * with another memory region
114 : : * @begin: virtual address of the beginning of the memory regien
115 : : * @end: virtual address of the end of the memory region
116 : : * @virt: virtual address of the memory object
117 : : * @size: size of the memory object
118 : : *
119 : : * Returns: true if an object's memory region, specified by @virt and @size,
120 : : * intersects with the region specified by @begin and @end, false otherwise.
121 : : */
122 : : static inline bool memory_intersects(void *begin, void *end, void *virt,
123 : : size_t size)
124 : : {
125 : 0 : void *vend = virt + size;
126 : :
127 [ # # # # ]: 0 : return (virt >= begin && virt < end) || (vend >= begin && vend < end);
128 : : }
129 : :
130 : : /**
131 : : * init_section_contains - checks if an object is contained within the init
132 : : * section
133 : : * @virt: virtual address of the memory object
134 : : * @size: size of the memory object
135 : : *
136 : : * Returns: true if the object specified by @virt and @size is entirely
137 : : * contained within the init section, false otherwise.
138 : : */
139 : : static inline bool init_section_contains(void *virt, size_t size)
140 : : {
141 : : return memory_contains(__init_begin, __init_end, virt, size);
142 : : }
143 : :
144 : : /**
145 : : * init_section_intersects - checks if the region occupied by an object
146 : : * intersects with the init section
147 : : * @virt: virtual address of the memory object
148 : : * @size: size of the memory object
149 : : *
150 : : * Returns: true if an object's memory region, specified by @virt and @size,
151 : : * intersects with the init section, false otherwise.
152 : : */
153 : : static inline bool init_section_intersects(void *virt, size_t size)
154 : : {
155 : : return memory_intersects(__init_begin, __init_end, virt, size);
156 : : }
157 : :
158 : : /**
159 : : * is_kernel_rodata - checks if the pointer address is located in the
160 : : * .rodata section
161 : : *
162 : : * @addr: address to check
163 : : *
164 : : * Returns: true if the address is located in .rodata, false otherwise.
165 : : */
166 : : static inline bool is_kernel_rodata(unsigned long addr)
167 : : {
168 [ + + + + : 11880776 : return addr >= (unsigned long)__start_rodata &&
+ + + + ]
169 : 5770140 : addr < (unsigned long)__end_rodata;
170 : : }
171 : :
172 : : #endif /* _ASM_GENERIC_SECTIONS_H_ */
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