| /* Kernel module help for i386. |
| Copyright (C) 2001 Rusty Russell. |
| |
| 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 |
| */ |
| #include <linux/moduleloader.h> |
| #include <linux/elf.h> |
| #include <linux/vmalloc.h> |
| #include <linux/fs.h> |
| #include <linux/string.h> |
| #include <linux/kernel.h> |
| |
| #if 0 |
| #define DEBUGP printk |
| #else |
| #define DEBUGP(fmt...) |
| #endif |
| |
| void *module_alloc(unsigned long size) |
| { |
| if (size == 0) |
| return NULL; |
| return vmalloc_exec(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. */ |
| } |
| |
| /* We don't need anything special. */ |
| int module_frob_arch_sections(Elf_Ehdr *hdr, |
| Elf_Shdr *sechdrs, |
| char *secstrings, |
| struct module *mod) |
| { |
| return 0; |
| } |
| |
| int apply_relocate(Elf32_Shdr *sechdrs, |
| const char *strtab, |
| unsigned int symindex, |
| unsigned int relsec, |
| struct module *me) |
| { |
| unsigned int i; |
| Elf32_Rel *rel = (void *)sechdrs[relsec].sh_addr; |
| Elf32_Sym *sym; |
| uint32_t *location; |
| |
| DEBUGP("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. Note that all |
| undefined symbols have been resolved. */ |
| sym = (Elf32_Sym *)sechdrs[symindex].sh_addr |
| + ELF32_R_SYM(rel[i].r_info); |
| |
| switch (ELF32_R_TYPE(rel[i].r_info)) { |
| case R_386_32: |
| /* We add the value into the location given */ |
| *location += sym->st_value; |
| break; |
| case R_386_PC32: |
| /* Add the value, subtract its postition */ |
| *location += sym->st_value - (uint32_t)location; |
| break; |
| default: |
| printk(KERN_ERR "module %s: Unknown relocation: %u\n", |
| me->name, ELF32_R_TYPE(rel[i].r_info)); |
| return -ENOEXEC; |
| } |
| } |
| return 0; |
| } |
| |
| int apply_relocate_add(Elf32_Shdr *sechdrs, |
| const char *strtab, |
| unsigned int symindex, |
| unsigned int relsec, |
| struct module *me) |
| { |
| printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n", |
| me->name); |
| return -ENOEXEC; |
| } |
| |
| int module_finalize(const Elf_Ehdr *hdr, |
| const Elf_Shdr *sechdrs, |
| struct module *me) |
| { |
| const Elf_Shdr *s, *text = NULL, *alt = NULL, *locks = NULL, |
| *para = NULL; |
| char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; |
| |
| for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) { |
| if (!strcmp(".text", secstrings + s->sh_name)) |
| text = s; |
| if (!strcmp(".altinstructions", secstrings + s->sh_name)) |
| alt = s; |
| if (!strcmp(".smp_locks", secstrings + s->sh_name)) |
| locks= s; |
| if (!strcmp(".parainstructions", secstrings + s->sh_name)) |
| para = s; |
| } |
| |
| if (alt) { |
| /* patch .altinstructions */ |
| void *aseg = (void *)alt->sh_addr; |
| apply_alternatives(aseg, aseg + alt->sh_size); |
| } |
| if (locks && text) { |
| void *lseg = (void *)locks->sh_addr; |
| void *tseg = (void *)text->sh_addr; |
| alternatives_smp_module_add(me, me->name, |
| lseg, lseg + locks->sh_size, |
| tseg, tseg + text->sh_size); |
| } |
| |
| if (para) { |
| void *pseg = (void *)para->sh_addr; |
| apply_paravirt(pseg, pseg + para->sh_size); |
| } |
| |
| return 0; |
| } |
| |
| void module_arch_cleanup(struct module *mod) |
| { |
| alternatives_smp_module_del(mod); |
| } |