// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) */ #include <linux/module.h>#include <linux/moduleloader.h>#include <linux/kernel.h>#include <linux/elf.h>#include <linux/vmalloc.h>#include <linux/slab.h>#include <linux/fs.h>#include <linux/string.h>#include <asm/unwind.h> static inline void arc_write_me(unsigned short *addr, unsigned long value){	*addr = (value & 0xffff0000) >> 16;	*(addr + 1) = (value & 0xffff);} /* * This gets called before relocation loop in generic loader * Make a note of the section index of unwinding section */int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,			      char *secstr, struct module *mod){#ifdef CONFIG_ARC_DW2_UNWIND	mod->arch.unw_sec_idx = 0;	mod->arch.unw_info = NULL;#endif	mod->arch.secstr = secstr;	return 0;} void module_arch_cleanup(struct module *mod){#ifdef CONFIG_ARC_DW2_UNWIND	if (mod->arch.unw_info)		unwind_remove_table(mod->arch.unw_info, 0);#endif} int apply_relocate_add(Elf32_Shdr *sechdrs,		       const char *strtab,		       unsigned int symindex,	/* sec index for sym tbl */		       unsigned int relsec,	/* sec index for relo sec */		       struct module *module){	int i, n, relo_type;	Elf32_Rela *rel_entry = (void *)sechdrs[relsec].sh_addr;	Elf32_Sym *sym_entry, *sym_sec;	Elf32_Addr relocation, location, tgt_addr;	unsigned int tgtsec; 	/*	 * @relsec has relocations e.g. .rela.init.text	 * @tgtsec is section to patch e.g. .init.text	 */	tgtsec = sechdrs[relsec].sh_info;	tgt_addr = sechdrs[tgtsec].sh_addr;	sym_sec = (Elf32_Sym *) sechdrs[symindex].sh_addr;	n = sechdrs[relsec].sh_size / sizeof(*rel_entry); 	pr_debug("\nSection to fixup %s @%x\n",		 module->arch.secstr + sechdrs[tgtsec].sh_name, tgt_addr);	pr_debug("=========================================================\n");	pr_debug("r_off\tr_add\tst_value ADDRESS  VALUE\n");	pr_debug("=========================================================\n"); 	/* Loop thru entries in relocation section */	for (i = 0; i < n; i++) {		const char *s; 		/* This is where to make the change */		location = tgt_addr + rel_entry[i].r_offset; 		/* This is the symbol it is referring to.  Note that all		   undefined symbols have been resolved.  */		sym_entry = sym_sec + ELF32_R_SYM(rel_entry[i].r_info); 		relocation = sym_entry->st_value + rel_entry[i].r_addend; 		if (sym_entry->st_name == 0 && ELF_ST_TYPE (sym_entry->st_info) == STT_SECTION) {			s = module->arch.secstr + sechdrs[sym_entry->st_shndx].sh_name;		} else {			s = strtab + sym_entry->st_name;		} 		pr_debug("   %x\t%x\t%x %x %x [%s]\n",			 rel_entry[i].r_offset, rel_entry[i].r_addend,			 sym_entry->st_value, location, relocation, s); 		/* This assumes modules are built with -mlong-calls		 * so any branches/jumps are absolute 32 bit jmps		 * global data access again is abs 32 bit.		 * Both of these are handled by same relocation type		 */		relo_type = ELF32_R_TYPE(rel_entry[i].r_info); 		if (likely(R_ARC_32_ME == relo_type))	/* ME ( S + A ) */			arc_write_me((unsigned short *)location, relocation);		else if (R_ARC_32 == relo_type)		/* ( S + A ) */			*((Elf32_Addr *) location) = relocation;		else if (R_ARC_32_PCREL == relo_type)	/* ( S + A ) - PDATA ) */			*((Elf32_Addr *) location) = relocation - location;		else			goto relo_err; 	} #ifdef CONFIG_ARC_DW2_UNWIND	if (strcmp(module->arch.secstr+sechdrs[tgtsec].sh_name, ".eh_frame") == 0)		module->arch.unw_sec_idx = tgtsec;#endif 	return 0; relo_err:	pr_err("%s: unknown relocation: %u\n",		module->name, ELF32_R_TYPE(rel_entry[i].r_info));	return -ENOEXEC; } /* Just before lift off: After sections have been relocated, we add the * dwarf section to unwinder table pool * This couldn't be done in module_frob_arch_sections() because * relocations had not been applied by then */int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,		    struct module *mod){#ifdef CONFIG_ARC_DW2_UNWIND	void *unw;	int unwsec = mod->arch.unw_sec_idx; 	if (unwsec) {		unw = unwind_add_table(mod, (void *)sechdrs[unwsec].sh_addr,				       sechdrs[unwsec].sh_size);		mod->arch.unw_info = unw;	}#endif	return 0;}