blob: e1ca588eb69d15d62d2486f5d8dec7549efdc8ab [file] [log] [blame]
/* 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_cached symbol_tree;
struct list_head symbol_list;
struct list_head reloc_list;
struct section *base, *reloc;
struct symbol *sym;
Elf_Data *data;
char *name;
int idx;
bool changed, text, rodata, noinstr, init, truncate;
struct reloc *reloc_data;
};
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, len;
unsigned long offset;
unsigned long __subtree_last;
struct symbol *pfunc, *cfunc, *alias;
unsigned char bind, type;
u8 uaccess_safe : 1;
u8 static_call_tramp : 1;
u8 retpoline_thunk : 1;
u8 return_thunk : 1;
u8 fentry : 1;
u8 profiling_func : 1;
struct list_head pv_target;
struct list_head reloc_list;
};
struct reloc {
struct list_head list;
struct hlist_node hash;
union {
GElf_Rela rela;
GElf_Rel rel;
};
struct section *sec;
struct symbol *sym;
struct list_head sym_reloc_entry;
unsigned long offset;
unsigned int type;
s64 addend;
int idx;
bool jump_table_start;
};
#define ELF_HASH_BITS 20
struct elf {
Elf *elf;
GElf_Ehdr ehdr;
int fd;
bool changed;
char *name;
unsigned int text_size, num_files;
struct list_head sections;
int symbol_bits;
int symbol_name_bits;
int section_bits;
int section_name_bits;
int reloc_bits;
struct hlist_head *symbol_hash;
struct hlist_head *symbol_name_hash;
struct hlist_head *section_hash;
struct hlist_head *section_name_hash;
struct hlist_head *reloc_hash;
struct section *section_data;
struct symbol *symbol_data;
};
#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 >= ((_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 reloc_hash(struct reloc *reloc)
{
return sec_offset_hash(reloc->sec, reloc->offset);
}
/*
* Try to see if it's a whole archive (vmlinux.o or module).
*
* Note this will miss the case where a module only has one source file.
*/
static inline bool has_multiple_files(struct elf *elf)
{
return elf->num_files > 1;
}
static inline int elf_class_addrsize(struct elf *elf)
{
if (elf->ehdr.e_ident[EI_CLASS] == ELFCLASS32)
return sizeof(u32);
else
return sizeof(u64);
}
struct elf *elf_open_read(const char *name, int flags);
struct section *elf_create_section(struct elf *elf, const char *name, unsigned int sh_flags, size_t entsize, int nr);
struct symbol *elf_create_prefix_symbol(struct elf *elf, struct symbol *orig, long size);
int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset,
unsigned int type, struct symbol *sym, s64 addend);
int elf_add_reloc_to_insn(struct elf *elf, struct section *sec,
unsigned long offset, unsigned int type,
struct section *insn_sec, unsigned long insn_off);
int elf_write_insn(struct elf *elf, struct section *sec,
unsigned long offset, unsigned int len,
const char *insn);
int elf_write_reloc(struct elf *elf, struct reloc *reloc);
int elf_write(struct elf *elf);
void elf_close(struct elf *elf);
struct section *find_section_by_name(const 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(const struct elf *elf, const char *name);
struct symbol *find_symbol_containing(const struct section *sec, unsigned long offset);
int find_symbol_hole_containing(const struct section *sec, unsigned long offset);
struct reloc *find_reloc_by_dest(const struct elf *elf, struct section *sec, unsigned long offset);
struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *sec,
unsigned long offset, unsigned int len);
struct symbol *find_func_containing(struct section *sec, unsigned long offset);
#define for_each_sec(file, sec) \
list_for_each_entry(sec, &file->elf->sections, list)
#define sec_for_each_sym(sec, sym) \
list_for_each_entry(sym, &sec->symbol_list, list)
#define for_each_sym(file, sym) \
for (struct section *__sec, *__fake = (struct section *)1; \
__fake; __fake = NULL) \
for_each_sec(file, __sec) \
sec_for_each_sym(__sec, sym)
#endif /* _OBJTOOL_ELF_H */