text: /*
   * Copyright (C) 2012 ARM Ltd.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  #ifndef __ASM_MODULE_H
  #define __ASM_MODULE_H
  
  #include <asm-generic/module.h>
  
  #define MODULE_ARCH_VERMAGIC	"aarch64"
  
  #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_trampoline;
  };
  #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 */
  