1 /* 2 * linux/arch/arm/kernel/module.c 3 * 4 * Copyright (C) 2002 Russell King. 5 * Modified for nommu by Hyok S. Choi 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * Module allocation method suggested by Andi Kleen. 12 */ 13 #include <linux/module.h> 14 #include <linux/moduleloader.h> 15 #include <linux/kernel.h> 16 #include <linux/elf.h> 17 #include <linux/vmalloc.h> 18 #include <linux/slab.h> 19 #include <linux/fs.h> 20 #include <linux/string.h> 21 22 #include <asm/pgtable.h> 23 24 #ifdef CONFIG_XIP_KERNEL 25 /* 26 * The XIP kernel text is mapped in the module area for modules and 27 * some other stuff to work without any indirect relocations. 28 * MODULE_START is redefined here and not in asm/memory.h to avoid 29 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off. 30 */ 31 extern void _etext; 32 #undef MODULE_START 33 #define MODULE_START (((unsigned long)&_etext + ~PGDIR_MASK) & PGDIR_MASK) 34 #endif 35 36 #ifdef CONFIG_MMU 37 void *module_alloc(unsigned long size) 38 { 39 struct vm_struct *area; 40 41 size = PAGE_ALIGN(size); 42 if (!size) 43 return NULL; 44 45 area = __get_vm_area(size, VM_ALLOC, MODULE_START, MODULE_END); 46 if (!area) 47 return NULL; 48 49 return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL); 50 } 51 #else /* CONFIG_MMU */ 52 void *module_alloc(unsigned long size) 53 { 54 return size == 0 ? NULL : vmalloc(size); 55 } 56 #endif /* !CONFIG_MMU */ 57 58 void module_free(struct module *module, void *region) 59 { 60 vfree(region); 61 } 62 63 int module_frob_arch_sections(Elf_Ehdr *hdr, 64 Elf_Shdr *sechdrs, 65 char *secstrings, 66 struct module *mod) 67 { 68 return 0; 69 } 70 71 int 72 apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, 73 unsigned int relindex, struct module *module) 74 { 75 Elf32_Shdr *symsec = sechdrs + symindex; 76 Elf32_Shdr *relsec = sechdrs + relindex; 77 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info; 78 Elf32_Rel *rel = (void *)relsec->sh_addr; 79 unsigned int i; 80 81 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) { 82 unsigned long loc; 83 Elf32_Sym *sym; 84 s32 offset; 85 86 offset = ELF32_R_SYM(rel->r_info); 87 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) { 88 printk(KERN_ERR "%s: bad relocation, section %d reloc %d\n", 89 module->name, relindex, i); 90 return -ENOEXEC; 91 } 92 93 sym = ((Elf32_Sym *)symsec->sh_addr) + offset; 94 95 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) { 96 printk(KERN_ERR "%s: out of bounds relocation, " 97 "section %d reloc %d offset %d size %d\n", 98 module->name, relindex, i, rel->r_offset, 99 dstsec->sh_size); 100 return -ENOEXEC; 101 } 102 103 loc = dstsec->sh_addr + rel->r_offset; 104 105 switch (ELF32_R_TYPE(rel->r_info)) { 106 case R_ARM_ABS32: 107 *(u32 *)loc += sym->st_value; 108 break; 109 110 case R_ARM_PC24: 111 case R_ARM_CALL: 112 case R_ARM_JUMP24: 113 offset = (*(u32 *)loc & 0x00ffffff) << 2; 114 if (offset & 0x02000000) 115 offset -= 0x04000000; 116 117 offset += sym->st_value - loc; 118 if (offset & 3 || 119 offset <= (s32)0xfe000000 || 120 offset >= (s32)0x02000000) { 121 printk(KERN_ERR 122 "%s: relocation out of range, section " 123 "%d reloc %d sym '%s'\n", module->name, 124 relindex, i, strtab + sym->st_name); 125 return -ENOEXEC; 126 } 127 128 offset >>= 2; 129 130 *(u32 *)loc &= 0xff000000; 131 *(u32 *)loc |= offset & 0x00ffffff; 132 break; 133 134 default: 135 printk(KERN_ERR "%s: unknown relocation: %u\n", 136 module->name, ELF32_R_TYPE(rel->r_info)); 137 return -ENOEXEC; 138 } 139 } 140 return 0; 141 } 142 143 int 144 apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab, 145 unsigned int symindex, unsigned int relsec, struct module *module) 146 { 147 printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n", 148 module->name); 149 return -ENOEXEC; 150 } 151 152 int 153 module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs, 154 struct module *module) 155 { 156 return 0; 157 } 158 159 void 160 module_arch_cleanup(struct module *mod) 161 { 162 } 163