Chris Metcalf | 867e359 | 2010-05-28 23:09:12 -0400 | [diff] [blame] | 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 | */ |
| 46 | void *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 | |
| 77 | error: |
| 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 */ |
| 86 | void module_free(struct module *mod, void *module_region) |
| 87 | { |
| 88 | vfree(module_region); |
| 89 | /* |
| 90 | * FIXME: If module_region == mod->init_region, trim exception |
| 91 | * table entries. |
| 92 | */ |
| 93 | } |
| 94 | |
| 95 | /* We don't need anything special. */ |
| 96 | int module_frob_arch_sections(Elf_Ehdr *hdr, |
| 97 | Elf_Shdr *sechdrs, |
| 98 | char *secstrings, |
| 99 | struct module *mod) |
| 100 | { |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | int apply_relocate(Elf_Shdr *sechdrs, |
| 105 | const char *strtab, |
| 106 | unsigned int symindex, |
| 107 | unsigned int relsec, |
| 108 | struct module *me) |
| 109 | { |
Chris Metcalf | 0707ad3 | 2010-06-25 17:04:17 -0400 | [diff] [blame] | 110 | pr_err("module %s: .rel relocation unsupported\n", me->name); |
Chris Metcalf | 867e359 | 2010-05-28 23:09:12 -0400 | [diff] [blame] | 111 | return -ENOEXEC; |
| 112 | } |
| 113 | |
| 114 | #ifdef __tilegx__ |
| 115 | /* |
| 116 | * Validate that the high 16 bits of "value" is just the sign-extension of |
| 117 | * the low 48 bits. |
| 118 | */ |
| 119 | static int validate_hw2_last(long value, struct module *me) |
| 120 | { |
| 121 | if (((value << 16) >> 16) != value) { |
Chris Metcalf | 0707ad3 | 2010-06-25 17:04:17 -0400 | [diff] [blame] | 122 | pr_warning("module %s: Out of range HW2_LAST value %#lx\n", |
| 123 | me->name, value); |
Chris Metcalf | 867e359 | 2010-05-28 23:09:12 -0400 | [diff] [blame] | 124 | return 0; |
| 125 | } |
| 126 | return 1; |
| 127 | } |
| 128 | |
| 129 | /* |
| 130 | * Validate that "value" isn't too big to hold in a JumpOff relocation. |
| 131 | */ |
| 132 | static int validate_jumpoff(long value) |
| 133 | { |
| 134 | /* Determine size of jump offset. */ |
| 135 | int shift = __builtin_clzl(get_JumpOff_X1(create_JumpOff_X1(-1))); |
| 136 | |
| 137 | /* Check to see if it fits into the relocation slot. */ |
| 138 | long f = get_JumpOff_X1(create_JumpOff_X1(value)); |
| 139 | f = (f << shift) >> shift; |
| 140 | |
| 141 | return f == value; |
| 142 | } |
| 143 | #endif |
| 144 | |
| 145 | int apply_relocate_add(Elf_Shdr *sechdrs, |
| 146 | const char *strtab, |
| 147 | unsigned int symindex, |
| 148 | unsigned int relsec, |
| 149 | struct module *me) |
| 150 | { |
| 151 | unsigned int i; |
| 152 | Elf_Rela *rel = (void *)sechdrs[relsec].sh_addr; |
| 153 | Elf_Sym *sym; |
| 154 | u64 *location; |
| 155 | unsigned long value; |
| 156 | |
| 157 | DEBUGP("Applying relocate section %u to %u\n", relsec, |
| 158 | sechdrs[relsec].sh_info); |
| 159 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { |
| 160 | /* This is where to make the change */ |
| 161 | location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr |
| 162 | + rel[i].r_offset; |
| 163 | /* |
| 164 | * This is the symbol it is referring to. |
| 165 | * Note that all undefined symbols have been resolved. |
| 166 | */ |
| 167 | sym = (Elf_Sym *)sechdrs[symindex].sh_addr |
| 168 | + ELF_R_SYM(rel[i].r_info); |
| 169 | value = sym->st_value + rel[i].r_addend; |
| 170 | |
| 171 | switch (ELF_R_TYPE(rel[i].r_info)) { |
| 172 | |
| 173 | #define MUNGE(func) (*location = ((*location & ~func(-1)) | func(value))) |
| 174 | |
| 175 | #ifndef __tilegx__ |
| 176 | case R_TILE_32: |
| 177 | *(uint32_t *)location = value; |
| 178 | break; |
| 179 | case R_TILE_IMM16_X0_HA: |
| 180 | value = (value + 0x8000) >> 16; |
| 181 | /*FALLTHROUGH*/ |
| 182 | case R_TILE_IMM16_X0_LO: |
| 183 | MUNGE(create_Imm16_X0); |
| 184 | break; |
| 185 | case R_TILE_IMM16_X1_HA: |
| 186 | value = (value + 0x8000) >> 16; |
| 187 | /*FALLTHROUGH*/ |
| 188 | case R_TILE_IMM16_X1_LO: |
| 189 | MUNGE(create_Imm16_X1); |
| 190 | break; |
| 191 | case R_TILE_JOFFLONG_X1: |
| 192 | value -= (unsigned long) location; /* pc-relative */ |
| 193 | value = (long) value >> 3; /* count by instrs */ |
| 194 | MUNGE(create_JOffLong_X1); |
| 195 | break; |
| 196 | #else |
| 197 | case R_TILEGX_64: |
| 198 | *location = value; |
| 199 | break; |
| 200 | case R_TILEGX_IMM16_X0_HW2_LAST: |
| 201 | if (!validate_hw2_last(value, me)) |
| 202 | return -ENOEXEC; |
| 203 | value >>= 16; |
| 204 | /*FALLTHROUGH*/ |
| 205 | case R_TILEGX_IMM16_X0_HW1: |
| 206 | value >>= 16; |
| 207 | /*FALLTHROUGH*/ |
| 208 | case R_TILEGX_IMM16_X0_HW0: |
| 209 | MUNGE(create_Imm16_X0); |
| 210 | break; |
| 211 | case R_TILEGX_IMM16_X1_HW2_LAST: |
| 212 | if (!validate_hw2_last(value, me)) |
| 213 | return -ENOEXEC; |
| 214 | value >>= 16; |
| 215 | /*FALLTHROUGH*/ |
| 216 | case R_TILEGX_IMM16_X1_HW1: |
| 217 | value >>= 16; |
| 218 | /*FALLTHROUGH*/ |
| 219 | case R_TILEGX_IMM16_X1_HW0: |
| 220 | MUNGE(create_Imm16_X1); |
| 221 | break; |
| 222 | case R_TILEGX_JUMPOFF_X1: |
| 223 | value -= (unsigned long) location; /* pc-relative */ |
| 224 | value = (long) value >> 3; /* count by instrs */ |
| 225 | if (!validate_jumpoff(value)) { |
Chris Metcalf | 0707ad3 | 2010-06-25 17:04:17 -0400 | [diff] [blame] | 226 | pr_warning("module %s: Out of range jump to" |
| 227 | " %#llx at %#llx (%p)\n", me->name, |
| 228 | sym->st_value + rel[i].r_addend, |
| 229 | rel[i].r_offset, location); |
Chris Metcalf | 867e359 | 2010-05-28 23:09:12 -0400 | [diff] [blame] | 230 | return -ENOEXEC; |
| 231 | } |
| 232 | MUNGE(create_JumpOff_X1); |
| 233 | break; |
| 234 | #endif |
| 235 | |
| 236 | #undef MUNGE |
| 237 | |
| 238 | default: |
Chris Metcalf | 0707ad3 | 2010-06-25 17:04:17 -0400 | [diff] [blame] | 239 | pr_err("module %s: Unknown relocation: %d\n", |
Chris Metcalf | 867e359 | 2010-05-28 23:09:12 -0400 | [diff] [blame] | 240 | me->name, (int) ELF_R_TYPE(rel[i].r_info)); |
| 241 | return -ENOEXEC; |
| 242 | } |
| 243 | } |
| 244 | return 0; |
| 245 | } |
| 246 | |
| 247 | int module_finalize(const Elf_Ehdr *hdr, |
| 248 | const Elf_Shdr *sechdrs, |
| 249 | struct module *me) |
| 250 | { |
| 251 | /* FIXME: perhaps remove the "writable" bit from the TLB? */ |
| 252 | return 0; |
| 253 | } |
| 254 | |
| 255 | void module_arch_cleanup(struct module *mod) |
| 256 | { |
| 257 | } |