/* *  This program is free software; you can redistribute it and/or modify *  it under the terms of the GNU General Public License as published by *  the Free Software Foundation; either version 2 of the License, or *  (at your option) any later version. * *  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, write to the Free Software *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA * *  Copyright (C) 2001 Rusty Russell. *  Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org) */ #undef DEBUG #include <linux/moduleloader.h>#include <linux/elf.h>#include <linux/vmalloc.h>#include <linux/slab.h>#include <linux/fs.h>#include <linux/string.h>#include <linux/kernel.h> struct mips_hi16 {	struct mips_hi16 *next;	Elf32_Addr *addr;	Elf64_Addr value;}; static struct mips_hi16 *mips_hi16_list; void *module_alloc(unsigned long size){	if (size == 0)		return NULL;	return vmalloc(size);}  /* Free memory returned from module_alloc */void module_free(struct module *mod, void *module_region){	vfree(module_region);	/* FIXME: If module_region == mod->init_region, trim exception           table entries. */} int module_frob_arch_sections(Elf_Ehdr *hdr,			      Elf_Shdr *sechdrs,			      char *secstrings,			      struct module *mod){	return 0;} int apply_relocate(Elf64_Shdr *sechdrs,		   const char *strtab,		   unsigned int symindex,		   unsigned int relsec,		   struct module *me){	/*	 * We don't want to deal with REL relocations - RELA is so much saner.	 */	if (!sechdrs[relsec].sh_size)		return 0; 	printk(KERN_ERR "module %s: REL relocation unsupported\n",	       me->name);	return -ENOEXEC;} static int apply_r_mips_none(struct module *me, uint32_t *location,	Elf64_Addr v){	return 0;} static int apply_r_mips_32(struct module *me, uint32_t *location,	Elf64_Addr v){	*location = v; 	return 0;} static int apply_r_mips_26(struct module *me, uint32_t *location,	Elf64_Addr v){	if (v % 4) {		printk(KERN_ERR "module %s: dangerous relocation\n", me->name);		return -ENOEXEC;	} 	if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {		printk(KERN_ERR		       "module %s: relocation overflow\n",		       me->name);		return -ENOEXEC;	} 	*location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff); 	return 0;} static int apply_r_mips_hi16(struct module *me, uint32_t *location,	Elf64_Addr v){	struct mips_hi16 *n; 	/*	 * We cannot relocate this one now because we don't know the value of	 * the carry we need to add.  Save the information, and let LO16 do the	 * actual relocation.	 */	n = kmalloc(sizeof *n, GFP_KERNEL);	if (!n)		return -ENOMEM; 	n->addr = location;	n->value = v;	n->next = mips_hi16_list;	mips_hi16_list = n; 	return 0;} static int apply_r_mips_lo16(struct module *me, uint32_t *location,	Elf64_Addr v){	unsigned long insnlo = *location;	Elf32_Addr val, vallo; 	/* Sign extend the addend we extract from the lo insn.  */	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000; 	if (mips_hi16_list != NULL) {		struct mips_hi16 *l; 		l = mips_hi16_list;		while (l != NULL) {			struct mips_hi16 *next;			unsigned long insn; 			/*			 * The value for the HI16 had best be the same.			 */			if (v != l->value)				goto out_danger; 			/*			 * Do the HI16 relocation.  Note that we actually don't			 * need to know anything about the LO16 itself, except			 * where to find the low 16 bits of the addend needed			 * by the LO16.			 */			insn = *l->addr;			val = ((insn & 0xffff) << 16) + vallo;			val += v; 			/*			 * Account for the sign extension that will happen in			 * the low bits.			 */			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff; 			insn = (insn & ~0xffff) | val;			*l->addr = insn; 			next = l->next;			kfree(l);			l = next;		} 		mips_hi16_list = NULL;	} 	/*	 * Ok, we're done with the HI16 relocs.  Now deal with the LO16.	 */	insnlo = (insnlo & ~0xffff) | (v & 0xffff);	*location = insnlo; 	return 0; out_danger:	printk(KERN_ERR "module %s: dangerous " "relocation\n", me->name); 	return -ENOEXEC;} static int apply_r_mips_64(struct module *me, uint32_t *location,	Elf64_Addr v){	*(uint64_t *) location = v; 	return 0;}  static int apply_r_mips_higher(struct module *me, uint32_t *location,	Elf64_Addr v){	*location = (*location & 0xffff0000) |	            ((((long long) v + 0x80008000LL) >> 32) & 0xffff); 	return 0;} static int apply_r_mips_highest(struct module *me, uint32_t *location,	Elf64_Addr v){	*location = (*location & 0xffff0000) |	            ((((long long) v + 0x800080008000LL) >> 48) & 0xffff); 	return 0;} static int (*reloc_handlers[]) (struct module *me, uint32_t *location,	Elf64_Addr v) = {	[R_MIPS_NONE]		= apply_r_mips_none,	[R_MIPS_32]		= apply_r_mips_32,	[R_MIPS_26]		= apply_r_mips_26,	[R_MIPS_HI16]		= apply_r_mips_hi16,	[R_MIPS_LO16]		= apply_r_mips_lo16,	[R_MIPS_64]		= apply_r_mips_64,	[R_MIPS_HIGHER]		= apply_r_mips_higher,	[R_MIPS_HIGHEST]	= apply_r_mips_highest}; int apply_relocate_add(Elf64_Shdr *sechdrs,		       const char *strtab,		       unsigned int symindex,		       unsigned int relsec,		       struct module *me){	Elf64_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr;	Elf64_Sym *sym;	uint32_t *location;	unsigned int i;	Elf64_Addr v;	int res; 	pr_debug("Applying relocate section %u to %u\n", relsec,	       sechdrs[relsec].sh_info); 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {		/* This is where to make the change */		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr			+ rel[i].r_offset;		/* This is the symbol it is referring to */		sym = (Elf64_Sym *)sechdrs[symindex].sh_addr + rel[i].r_sym;		if (!sym->st_value) {			printk(KERN_WARNING "%s: Unknown symbol %s\n",			       me->name, strtab + sym->st_name);			return -ENOENT;		} 		v = sym->st_value; 		res = reloc_handlers[rel[i].r_type](me, location, v);		if (res)			return res;	} 	return 0;}