module.h
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Ltd.
*/
#ifndef __ASM_MODULE_H
#define __ASM_MODULE_H
#include <asm-generic/module.h>
#ifdef CONFIG_ARM64_MODULE_PLTS
struct mod_plt_sec {
int plt_shndx;
int plt_num_entries;
int plt_max_entries;
};
struct mod_arch_specific {
struct mod_plt_sec core;
struct mod_plt_sec init;
/* for CONFIG_DYNAMIC_FTRACE */
struct plt_entry *ftrace_trampolines;
};
#endif
u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs,
void *loc, const Elf64_Rela *rela,
Elf64_Sym *sym);
u64 module_emit_veneer_for_adrp(struct module *mod, Elf64_Shdr *sechdrs,
void *loc, u64 val);
#ifdef CONFIG_RANDOMIZE_BASE
extern u64 module_alloc_base;
#else
#define module_alloc_base ((u64)_etext - MODULES_VSIZE)
#endif
struct plt_entry {
/*
* A program that conforms to the AArch64 Procedure Call Standard
* (AAPCS64) must assume that a veneer that alters IP0 (x16) and/or
* IP1 (x17) may be inserted at any branch instruction that is
* exposed to a relocation that supports long branches. Since that
* is exactly what we are dealing with here, we are free to use x16
* as a scratch register in the PLT veneers.
*/
__le32 adrp; /* adrp x16, .... */
__le32 add; /* add x16, x16, #0x.... */
__le32 br; /* br x16 */
};
static inline bool is_forbidden_offset_for_adrp(void *place)
{
return IS_ENABLED(CONFIG_ARM64_ERRATUM_843419) &&
cpus_have_const_cap(ARM64_WORKAROUND_843419) &&
((u64)place & 0xfff) >= 0xff8;
}
struct plt_entry get_plt_entry(u64 dst, void *pc);
bool plt_entries_equal(const struct plt_entry *a, const struct plt_entry *b);
static inline bool plt_entry_is_initialized(const struct plt_entry *e)
{
return e->adrp || e->add || e->br;
}
#endif /* __ASM_MODULE_H */