1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2012 ARM Ltd. 4 */ 5 #ifndef __ASM_MODULE_H 6 #define __ASM_MODULE_H 7 8 #include <asm-generic/module.h> 9 10 #ifdef CONFIG_ARM64_MODULE_PLTS 11 struct mod_plt_sec { 12 int plt_shndx; 13 int plt_num_entries; 14 int plt_max_entries; 15 }; 16 17 struct mod_arch_specific { 18 struct mod_plt_sec core; 19 struct mod_plt_sec init; 20 21 /* for CONFIG_DYNAMIC_FTRACE */ 22 struct plt_entry *ftrace_trampolines; 23 }; 24 #endif 25 26 u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs, 27 void *loc, const Elf64_Rela *rela, 28 Elf64_Sym *sym); 29 30 u64 module_emit_veneer_for_adrp(struct module *mod, Elf64_Shdr *sechdrs, 31 void *loc, u64 val); 32 33 #ifdef CONFIG_RANDOMIZE_BASE 34 extern u64 module_alloc_base; 35 #else 36 #define module_alloc_base ((u64)_etext - MODULES_VSIZE) 37 #endif 38 39 struct plt_entry { 40 /* 41 * A program that conforms to the AArch64 Procedure Call Standard 42 * (AAPCS64) must assume that a veneer that alters IP0 (x16) and/or 43 * IP1 (x17) may be inserted at any branch instruction that is 44 * exposed to a relocation that supports long branches. Since that 45 * is exactly what we are dealing with here, we are free to use x16 46 * as a scratch register in the PLT veneers. 47 */ 48 __le32 adrp; /* adrp x16, .... */ 49 __le32 add; /* add x16, x16, #0x.... */ 50 __le32 br; /* br x16 */ 51 }; 52 53 static inline bool is_forbidden_offset_for_adrp(void *place) 54 { 55 return IS_ENABLED(CONFIG_ARM64_ERRATUM_843419) && 56 cpus_have_const_cap(ARM64_WORKAROUND_843419) && 57 ((u64)place & 0xfff) >= 0xff8; 58 } 59 60 struct plt_entry get_plt_entry(u64 dst, void *pc); 61 62 static inline const Elf_Shdr *find_section(const Elf_Ehdr *hdr, 63 const Elf_Shdr *sechdrs, 64 const char *name) 65 { 66 const Elf_Shdr *s, *se; 67 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; 68 69 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) { 70 if (strcmp(name, secstrs + s->sh_name) == 0) 71 return s; 72 } 73 74 return NULL; 75 } 76 77 #endif /* __ASM_MODULE_H */ 78