Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
4 */
5
6#ifndef _OBJTOOL_ELF_H
7#define _OBJTOOL_ELF_H
8
9#include <stdio.h>
10#include <gelf.h>
11#include <linux/list.h>
12#include <linux/hashtable.h>
13#include <linux/rbtree.h>
14#include <linux/jhash.h>
15
16#ifdef LIBELF_USE_DEPRECATED
17# define elf_getshdrnum elf_getshnum
18# define elf_getshdrstrndx elf_getshstrndx
19#endif
20
21/*
22 * Fallback for systems without this "read, mmaping if possible" cmd.
23 */
24#ifndef ELF_C_READ_MMAP
25#define ELF_C_READ_MMAP ELF_C_READ
26#endif
27
28struct section {
29 struct list_head list;
30 struct hlist_node hash;
31 struct hlist_node name_hash;
32 GElf_Shdr sh;
33 struct rb_root symbol_tree;
34 struct list_head symbol_list;
35 struct list_head rela_list;
36 struct section *base, *rela;
37 struct symbol *sym;
38 Elf_Data *data;
39 char *name;
40 int idx;
41 unsigned int len;
42 bool changed, text, rodata, noinstr;
43};
44
45struct symbol {
46 struct list_head list;
47 struct rb_node node;
48 struct hlist_node hash;
49 struct hlist_node name_hash;
50 GElf_Sym sym;
51 struct section *sec;
52 char *name;
53 unsigned int idx;
54 unsigned char bind, type;
55 unsigned long offset;
56 unsigned int len;
57 struct symbol *pfunc, *cfunc, *alias;
58 bool uaccess_safe;
59};
60
61struct rela {
62 struct list_head list;
63 struct hlist_node hash;
64 GElf_Rela rela;
65 struct section *sec;
66 struct symbol *sym;
67 unsigned long offset;
68 unsigned int type;
69 int addend;
70 int idx;
71 bool jump_table_start;
72};
73
74#define ELF_HASH_BITS 20
75
76struct elf {
77 Elf *elf;
78 GElf_Ehdr ehdr;
79 int fd;
80 bool changed;
81 char *name;
82 struct list_head sections;
83 DECLARE_HASHTABLE(symbol_hash, ELF_HASH_BITS);
84 DECLARE_HASHTABLE(symbol_name_hash, ELF_HASH_BITS);
85 DECLARE_HASHTABLE(section_hash, ELF_HASH_BITS);
86 DECLARE_HASHTABLE(section_name_hash, ELF_HASH_BITS);
87 DECLARE_HASHTABLE(rela_hash, ELF_HASH_BITS);
88};
89
90#define OFFSET_STRIDE_BITS 4
91#define OFFSET_STRIDE (1UL << OFFSET_STRIDE_BITS)
92#define OFFSET_STRIDE_MASK (~(OFFSET_STRIDE - 1))
93
94#define for_offset_range(_offset, _start, _end) \
95 for (_offset = ((_start) & OFFSET_STRIDE_MASK); \
96 _offset >= ((_start) & OFFSET_STRIDE_MASK) && \
97 _offset <= ((_end) & OFFSET_STRIDE_MASK); \
98 _offset += OFFSET_STRIDE)
99
100static inline u32 sec_offset_hash(struct section *sec, unsigned long offset)
101{
102 u32 ol, oh, idx = sec->idx;
103
104 offset &= OFFSET_STRIDE_MASK;
105
106 ol = offset;
107 oh = (offset >> 16) >> 16;
108
109 __jhash_mix(ol, oh, idx);
110
111 return ol;
112}
113
114static inline u32 rela_hash(struct rela *rela)
115{
116 return sec_offset_hash(rela->sec, rela->offset);
117}
118
119struct elf *elf_open_read(const char *name, int flags);
120struct section *elf_create_section(struct elf *elf, const char *name, size_t entsize, int nr);
121struct section *elf_create_rela_section(struct elf *elf, struct section *base);
122void elf_add_rela(struct elf *elf, struct rela *rela);
123int elf_write_insn(struct elf *elf, struct section *sec,
124 unsigned long offset, unsigned int len,
125 const char *insn);
126int elf_write_rela(struct elf *elf, struct rela *rela);
127int elf_write(struct elf *elf);
128void elf_close(struct elf *elf);
129
130struct section *find_section_by_name(const struct elf *elf, const char *name);
131struct symbol *find_func_by_offset(struct section *sec, unsigned long offset);
132struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset);
133struct symbol *find_symbol_by_name(const struct elf *elf, const char *name);
134struct symbol *find_symbol_containing(const struct section *sec, unsigned long offset);
135struct rela *find_rela_by_dest(const struct elf *elf, struct section *sec, unsigned long offset);
136struct rela *find_rela_by_dest_range(const struct elf *elf, struct section *sec,
137 unsigned long offset, unsigned int len);
138struct symbol *find_func_containing(struct section *sec, unsigned long offset);
139int elf_rebuild_rela_section(struct elf *elf, struct section *sec);
140
141#define for_each_sec(file, sec) \
142 list_for_each_entry(sec, &file->elf->sections, list)
143
144#endif /* _OBJTOOL_ELF_H */