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8#include <linux/bsearch.h>
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/sort.h>
12#include <linux/uaccess.h>
13
14#ifndef ARCH_HAS_RELATIVE_EXTABLE
15#define ex_to_insn(x) ((x)->insn)
16#else
17static inline unsigned long ex_to_insn(const struct exception_table_entry *x)
18{
19 return (unsigned long)&x->insn + x->insn;
20}
21#endif
22
23#ifndef ARCH_HAS_SORT_EXTABLE
24#ifndef ARCH_HAS_RELATIVE_EXTABLE
25#define swap_ex NULL
26#else
27static void swap_ex(void *a, void *b, int size)
28{
29 struct exception_table_entry *x = a, *y = b, tmp;
30 int delta = b - a;
31
32 tmp = *x;
33 x->insn = y->insn + delta;
34 y->insn = tmp.insn - delta;
35
36#ifdef swap_ex_entry_fixup
37 swap_ex_entry_fixup(x, y, tmp, delta);
38#else
39 x->fixup = y->fixup + delta;
40 y->fixup = tmp.fixup - delta;
41#endif
42}
43#endif
44
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48
49
50
51static int cmp_ex_sort(const void *a, const void *b)
52{
53 const struct exception_table_entry *x = a, *y = b;
54
55
56 if (ex_to_insn(x) > ex_to_insn(y))
57 return 1;
58 if (ex_to_insn(x) < ex_to_insn(y))
59 return -1;
60 return 0;
61}
62
63void sort_extable(struct exception_table_entry *start,
64 struct exception_table_entry *finish)
65{
66 sort(start, finish - start, sizeof(struct exception_table_entry),
67 cmp_ex_sort, swap_ex);
68}
69
70#ifdef CONFIG_MODULES
71
72
73
74
75void trim_init_extable(struct module *m)
76{
77
78 while (m->num_exentries &&
79 within_module_init(ex_to_insn(&m->extable[0]), m)) {
80 m->extable++;
81 m->num_exentries--;
82 }
83
84 while (m->num_exentries &&
85 within_module_init(ex_to_insn(&m->extable[m->num_exentries - 1]),
86 m))
87 m->num_exentries--;
88}
89#endif
90#endif
91
92#ifndef ARCH_HAS_SEARCH_EXTABLE
93
94static int cmp_ex_search(const void *key, const void *elt)
95{
96 const struct exception_table_entry *_elt = elt;
97 unsigned long _key = *(unsigned long *)key;
98
99
100 if (_key > ex_to_insn(_elt))
101 return 1;
102 if (_key < ex_to_insn(_elt))
103 return -1;
104 return 0;
105}
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113
114const struct exception_table_entry *
115search_extable(const struct exception_table_entry *base,
116 const size_t num,
117 unsigned long value)
118{
119 return bsearch(&value, base, num,
120 sizeof(struct exception_table_entry), cmp_ex_search);
121}
122#endif
123