[thirdparty/linux.git] / tools / objtool / elf.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
 */

#ifndef _OBJTOOL_ELF_H
#define _OBJTOOL_ELF_H

#include <stdio.h>
#include <gelf.h>
#include <linux/list.h>
#include <linux/hashtable.h>
#include <linux/rbtree.h>
#include <linux/jhash.h>

#ifdef LIBELF_USE_DEPRECATED
# define elf_getshdrnum    elf_getshnum
# define elf_getshdrstrndx elf_getshstrndx
#endif

/*
 * Fallback for systems without this "read, mmaping if possible" cmd.
 */
#ifndef ELF_C_READ_MMAP
#define ELF_C_READ_MMAP ELF_C_READ
#endif

struct section {
	struct list_head list;
	struct hlist_node hash;
	struct hlist_node name_hash;
	GElf_Shdr sh;
	struct rb_root symbol_tree;
	struct list_head symbol_list;
	struct list_head rela_list;
	struct section *base, *rela;
	struct symbol *sym;
	Elf_Data *data;
	char *name;
	int idx;
	unsigned int len;
	bool changed, text, rodata;
};

struct symbol {
	struct list_head list;
	struct rb_node node;
	struct hlist_node hash;
	struct hlist_node name_hash;
	GElf_Sym sym;
	struct section *sec;
	char *name;
	unsigned int idx;
	unsigned char bind, type;
	unsigned long offset;
	unsigned int len;
	struct symbol *pfunc, *cfunc, *alias;
	bool uaccess_safe;
};

struct rela {
	struct list_head list;
	struct hlist_node hash;
	GElf_Rela rela;
	struct section *sec;
	struct symbol *sym;
	unsigned int type;
	unsigned long offset;
	int addend;
	bool jump_table_start;
};

struct elf {
	Elf *elf;
	GElf_Ehdr ehdr;
	int fd;
	char *name;
	struct list_head sections;
	DECLARE_HASHTABLE(symbol_hash, 20);
	DECLARE_HASHTABLE(symbol_name_hash, 20);
	DECLARE_HASHTABLE(section_hash, 16);
	DECLARE_HASHTABLE(section_name_hash, 16);
	DECLARE_HASHTABLE(rela_hash, 20);
};

#define OFFSET_STRIDE_BITS	4
#define OFFSET_STRIDE		(1UL << OFFSET_STRIDE_BITS)
#define OFFSET_STRIDE_MASK	(~(OFFSET_STRIDE - 1))

#define for_offset_range(_offset, _start, _end)		\
	for (_offset = ((_start) & OFFSET_STRIDE_MASK);	\
	     _offset <= ((_end) & OFFSET_STRIDE_MASK);	\
	     _offset += OFFSET_STRIDE)

static inline u32 sec_offset_hash(struct section *sec, unsigned long offset)
{
	u32 ol, oh, idx = sec->idx;

	offset &= OFFSET_STRIDE_MASK;

	ol = offset;
	oh = (offset >> 16) >> 16;

	__jhash_mix(ol, oh, idx);

	return ol;
}

static inline u32 rela_hash(struct rela *rela)
{
	return sec_offset_hash(rela->sec, rela->offset);
}

struct elf *elf_read(const char *name, int flags);
struct section *find_section_by_name(struct elf *elf, const char *name);
struct symbol *find_func_by_offset(struct section *sec, unsigned long offset);
struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset);
struct symbol *find_symbol_by_name(struct elf *elf, const char *name);
struct symbol *find_symbol_containing(struct section *sec, unsigned long offset);
struct rela *find_rela_by_dest(struct elf *elf, struct section *sec, unsigned long offset);
struct rela *find_rela_by_dest_range(struct elf *elf, struct section *sec,
				     unsigned long offset, unsigned int len);
struct symbol *find_func_containing(struct section *sec, unsigned long offset);
struct section *elf_create_section(struct elf *elf, const char *name, size_t
				   entsize, int nr);
struct section *elf_create_rela_section(struct elf *elf, struct section *base);
int elf_rebuild_rela_section(struct section *sec);
int elf_write(struct elf *elf);
void elf_close(struct elf *elf);

#define for_each_sec(file, sec)						\
	list_for_each_entry(sec, &file->elf->sections, list)

#endif /* _OBJTOOL_ELF_H */
Commit	Line	Data
1ccea77e	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
442f04c3 JP	2	/*
442f04c3 JP	3	* Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
442f04c3 JP	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>
042ba73f	12	#include <linux/hashtable.h>
2a362ecc	13	#include <linux/rbtree.h>
ae358196	14	#include <linux/jhash.h>
442f04c3	15
2e51f262 JB	16	#ifdef LIBELF_USE_DEPRECATED
	17	# define elf_getshdrnum elf_getshnum
	18	# define elf_getshdrstrndx elf_getshstrndx
	19	#endif
	20
627fce14 JP	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
442f04c3 JP	28	struct section {
442f04c3 JP	29	struct list_head list;
53038996	30	struct hlist_node hash;
ae358196	31	struct hlist_node name_hash;
442f04c3	32	GElf_Shdr sh;
2a362ecc	33	struct rb_root symbol_tree;
a196e171 JP	34	struct list_head symbol_list;
a196e171 JP	35	struct list_head rela_list;
442f04c3 JP	36	struct section base, rela;
442f04c3 JP	37	struct symbol *sym;
baa41469	38	Elf_Data *data;
442f04c3 JP	39	char *name;
442f04c3 JP	40	int idx;
442f04c3	41	unsigned int len;
4a60aa05	42	bool changed, text, rodata;
442f04c3 JP	43	};
	44
	45	struct symbol {
	46	struct list_head list;
2a362ecc	47	struct rb_node node;
042ba73f	48	struct hlist_node hash;
cdb3d057	49	struct hlist_node name_hash;
442f04c3 JP	50	GElf_Sym sym;
	51	struct section *sec;
	52	char *name;
042ba73f	53	unsigned int idx;
442f04c3 JP	54	unsigned char bind, type;
	55	unsigned long offset;
	56	unsigned int len;
09f30d83	57	struct symbol pfunc, cfunc, *alias;
ea24213d	58	bool uaccess_safe;
442f04c3 JP	59	};
	60
	61	struct rela {
	62	struct list_head list;
042ba73f	63	struct hlist_node hash;
442f04c3	64	GElf_Rela rela;
e7c2bc37	65	struct section *sec;
442f04c3 JP	66	struct symbol *sym;
442f04c3 JP	67	unsigned int type;
042ba73f	68	unsigned long offset;
442f04c3	69	int addend;
bd98c813	70	bool jump_table_start;
442f04c3 JP	71	};
	72
	73	struct elf {
	74	Elf *elf;
	75	GElf_Ehdr ehdr;
	76	int fd;
	77	char *name;
	78	struct list_head sections;
65fb11a7	79	DECLARE_HASHTABLE(symbol_hash, 20);
cdb3d057	80	DECLARE_HASHTABLE(symbol_name_hash, 20);
53038996	81	DECLARE_HASHTABLE(section_hash, 16);
ae358196	82	DECLARE_HASHTABLE(section_name_hash, 16);
8b5fa6bc	83	DECLARE_HASHTABLE(rela_hash, 20);
442f04c3 JP	84	};
442f04c3 JP	85
74b873e4 PZ	86	#define OFFSET_STRIDE_BITS 4
	87	#define OFFSET_STRIDE (1UL << OFFSET_STRIDE_BITS)
	88	#define OFFSET_STRIDE_MASK (~(OFFSET_STRIDE - 1))
	89
	90	#define for_offset_range(_offset, _start, _end) \
	91	for (_offset = ((_start) & OFFSET_STRIDE_MASK); \
	92	_offset <= ((_end) & OFFSET_STRIDE_MASK); \
	93	_offset += OFFSET_STRIDE)
	94
8b5fa6bc PZ	95	static inline u32 sec_offset_hash(struct section *sec, unsigned long offset)
8b5fa6bc PZ	96	{
74b873e4 PZ	97	u32 ol, oh, idx = sec->idx;
	98
	99	offset &= OFFSET_STRIDE_MASK;
	100
	101	ol = offset;
df2b3843	102	oh = (offset >> 16) >> 16;
8b5fa6bc PZ	103
	104	__jhash_mix(ol, oh, idx);
	105
	106	return ol;
	107	}
	108
	109	static inline u32 rela_hash(struct rela *rela)
	110	{
	111	return sec_offset_hash(rela->sec, rela->offset);
	112	}
442f04c3	113
8e144797	114	struct elf elf_read(const char name, int flags);
442f04c3	115	struct section find_section_by_name(struct elf elf, const char *name);
7acfe531	116	struct symbol find_func_by_offset(struct section sec, unsigned long offset);
442f04c3	117	struct symbol find_symbol_by_offset(struct section sec, unsigned long offset);
13810435	118	struct symbol find_symbol_by_name(struct elf elf, const char *name);
5c51f4ae	119	struct symbol find_symbol_containing(struct section sec, unsigned long offset);
8b5fa6bc PZ	120	struct rela find_rela_by_dest(struct elf elf, struct section *sec, unsigned long offset);
	121	struct rela find_rela_by_dest_range(struct elf elf, struct section *sec,
	122	unsigned long offset, unsigned int len);
53d20720	123	struct symbol find_func_containing(struct section sec, unsigned long offset);
627fce14 JP	124	struct section elf_create_section(struct elf elf, const char *name, size_t
	125	entsize, int nr);
	126	struct section elf_create_rela_section(struct elf elf, struct section *base);
	127	int elf_rebuild_rela_section(struct section *sec);
	128	int elf_write(struct elf *elf);
442f04c3 JP	129	void elf_close(struct elf *elf);
442f04c3 JP	130
baa41469 JP	131	#define for_each_sec(file, sec) \
baa41469 JP	132	list_for_each_entry(sec, &file->elf->sections, list)
442f04c3 JP	133
442f04c3 JP	134	#endif /* _OBJTOOL_ELF_H */