1/* 2 * Copyright 2010 Tilera Corporation. All Rights Reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation, version 2. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 11 * NON INFRINGEMENT. See the GNU General Public License for 12 * more details. 13 * 14 * Based on i386 version, copyright (C) 2001 Rusty Russell. 15 */ 16 17#include <linux/moduleloader.h> 18#include <linux/elf.h> 19#include <linux/vmalloc.h> 20#include <linux/fs.h> 21#include <linux/string.h> 22#include <linux/kernel.h> 23#include <asm/opcode-tile.h> 24#include <asm/pgtable.h> 25 26#ifdef __tilegx__ 27# define Elf_Rela Elf64_Rela 28# define ELF_R_SYM ELF64_R_SYM 29# define ELF_R_TYPE ELF64_R_TYPE 30#else 31# define Elf_Rela Elf32_Rela 32# define ELF_R_SYM ELF32_R_SYM 33# define ELF_R_TYPE ELF32_R_TYPE 34#endif 35 36#ifdef MODULE_DEBUG 37#define DEBUGP printk 38#else 39#define DEBUGP(fmt...) 40#endif 41 42/* 43 * Allocate some address space in the range MEM_MODULE_START to 44 * MEM_MODULE_END and populate it with memory. 45 */ 46void *module_alloc(unsigned long size) 47{ 48 struct page **pages; 49 pgprot_t prot_rwx = __pgprot(_PAGE_KERNEL | _PAGE_KERNEL_EXEC); 50 struct vm_struct *area; 51 int i = 0; 52 int npages; 53 54 if (size == 0) 55 return NULL; 56 npages = (size + PAGE_SIZE - 1) / PAGE_SIZE; 57 pages = kmalloc(npages * sizeof(struct page *), GFP_KERNEL); 58 if (pages == NULL) 59 return NULL; 60 for (; i < npages; ++i) { 61 pages[i] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM); 62 if (!pages[i]) 63 goto error; 64 } 65 66 area = __get_vm_area(size, VM_ALLOC, MEM_MODULE_START, MEM_MODULE_END); 67 if (!area) 68 goto error; 69 70 if (map_vm_area(area, prot_rwx, &pages)) { 71 vunmap(area->addr); 72 goto error; 73 } 74 75 return area->addr; 76 77error: 78 while (--i >= 0) 79 __free_page(pages[i]); 80 kfree(pages); 81 return NULL; 82} 83 84 85/* Free memory returned from module_alloc */ 86void module_free(struct module *mod, void *module_region) 87{ 88 vfree(module_region); 89} 90 91/* We don't need anything special. */ 92int module_frob_arch_sections(Elf_Ehdr *hdr, 93 Elf_Shdr *sechdrs, 94 char *secstrings, 95 struct module *mod) 96{ 97 return 0; 98} 99 100int apply_relocate(Elf_Shdr *sechdrs, 101 const char *strtab, 102 unsigned int symindex, 103 unsigned int relsec, 104 struct module *me) 105{ 106 pr_err("module %s: .rel relocation unsupported\n", me->name); 107 return -ENOEXEC; 108} 109 110#ifdef __tilegx__ 111/* 112 * Validate that the high 16 bits of "value" is just the sign-extension of 113 * the low 48 bits. 114 */ 115static int validate_hw2_last(long value, struct module *me) 116{ 117 if (((value << 16) >> 16) != value) { 118 pr_warning("module %s: Out of range HW2_LAST value %#lx\n", 119 me->name, value); 120 return 0; 121 } 122 return 1; 123} 124 125/* 126 * Validate that "value" isn't too big to hold in a JumpOff relocation. 127 */ 128static int validate_jumpoff(long value) 129{ 130 /* Determine size of jump offset. */ 131 int shift = __builtin_clzl(get_JumpOff_X1(create_JumpOff_X1(-1))); 132 133 /* Check to see if it fits into the relocation slot. */ 134 long f = get_JumpOff_X1(create_JumpOff_X1(value)); 135 f = (f << shift) >> shift; 136 137 return f == value; 138} 139#endif 140 141int apply_relocate_add(Elf_Shdr *sechdrs, 142 const char *strtab, 143 unsigned int symindex, 144 unsigned int relsec, 145 struct module *me) 146{ 147 unsigned int i; 148 Elf_Rela *rel = (void *)sechdrs[relsec].sh_addr; 149 Elf_Sym *sym; 150 u64 *location; 151 unsigned long value; 152 153 DEBUGP("Applying relocate section %u to %u\n", relsec, 154 sechdrs[relsec].sh_info); 155 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { 156 /* This is where to make the change */ 157 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr 158 + rel[i].r_offset; 159 /* 160 * This is the symbol it is referring to. 161 * Note that all undefined symbols have been resolved. 162 */ 163 sym = (Elf_Sym *)sechdrs[symindex].sh_addr 164 + ELF_R_SYM(rel[i].r_info); 165 value = sym->st_value + rel[i].r_addend; 166 167 switch (ELF_R_TYPE(rel[i].r_info)) { 168 169#define MUNGE(func) (*location = ((*location & ~func(-1)) | func(value))) 170 171#ifndef __tilegx__ 172 case R_TILE_32: 173 *(uint32_t *)location = value; 174 break; 175 case R_TILE_IMM16_X0_HA: 176 value = (value + 0x8000) >> 16; 177 /*FALLTHROUGH*/ 178 case R_TILE_IMM16_X0_LO: 179 MUNGE(create_Imm16_X0); 180 break; 181 case R_TILE_IMM16_X1_HA: 182 value = (value + 0x8000) >> 16; 183 /*FALLTHROUGH*/ 184 case R_TILE_IMM16_X1_LO: 185 MUNGE(create_Imm16_X1); 186 break; 187 case R_TILE_JOFFLONG_X1: 188 value -= (unsigned long) location; /* pc-relative */ 189 value = (long) value >> 3; /* count by instrs */ 190 MUNGE(create_JOffLong_X1); 191 break; 192#else 193 case R_TILEGX_64: 194 *location = value; 195 break; 196 case R_TILEGX_IMM16_X0_HW2_LAST: 197 if (!validate_hw2_last(value, me)) 198 return -ENOEXEC; 199 value >>= 16; 200 /*FALLTHROUGH*/ 201 case R_TILEGX_IMM16_X0_HW1: 202 value >>= 16; 203 /*FALLTHROUGH*/ 204 case R_TILEGX_IMM16_X0_HW0: 205 MUNGE(create_Imm16_X0); 206 break; 207 case R_TILEGX_IMM16_X1_HW2_LAST: 208 if (!validate_hw2_last(value, me)) 209 return -ENOEXEC; 210 value >>= 16; 211 /*FALLTHROUGH*/ 212 case R_TILEGX_IMM16_X1_HW1: 213 value >>= 16; 214 /*FALLTHROUGH*/ 215 case R_TILEGX_IMM16_X1_HW0: 216 MUNGE(create_Imm16_X1); 217 break; 218 case R_TILEGX_JUMPOFF_X1: 219 value -= (unsigned long) location; /* pc-relative */ 220 value = (long) value >> 3; /* count by instrs */ 221 if (!validate_jumpoff(value)) { 222 pr_warning("module %s: Out of range jump to" 223 " %#llx at %#llx (%p)\n", me->name, 224 sym->st_value + rel[i].r_addend, 225 rel[i].r_offset, location); 226 return -ENOEXEC; 227 } 228 MUNGE(create_JumpOff_X1); 229 break; 230#endif 231 232#undef MUNGE 233 234 default: 235 pr_err("module %s: Unknown relocation: %d\n", 236 me->name, (int) ELF_R_TYPE(rel[i].r_info)); 237 return -ENOEXEC; 238 } 239 } 240 return 0; 241} 242 243int module_finalize(const Elf_Ehdr *hdr, 244 const Elf_Shdr *sechdrs, 245 struct module *me) 246{ 247 return 0; 248} 249 250void module_arch_cleanup(struct module *mod) 251{ 252} 253