1#include <linux/init.h> 2#include <linux/proc_fs.h> 3#include <linux/capability.h> 4#include <linux/ctype.h> 5#include <linux/module.h> 6#include <linux/seq_file.h> 7#include <asm/uaccess.h> 8 9#define LINE_SIZE 80 10 11#include <asm/mtrr.h> 12#include "mtrr.h" 13 14/* RED-PEN: this is accessed without any locking */ 15extern unsigned int *usage_table; 16 17 18#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private) 19 20static const char *const mtrr_strings[MTRR_NUM_TYPES] = 21{ 22 "uncachable", /* 0 */ 23 "write-combining", /* 1 */ 24 "?", /* 2 */ 25 "?", /* 3 */ 26 "write-through", /* 4 */ 27 "write-protect", /* 5 */ 28 "write-back", /* 6 */ 29}; 30 31const char *mtrr_attrib_to_str(int x) 32{ 33 return (x <= 6) ? mtrr_strings[x] : "?"; 34} 35 36#ifdef CONFIG_PROC_FS 37 38static int 39mtrr_file_add(unsigned long base, unsigned long size, 40 unsigned int type, char increment, struct file *file, int page) 41{ 42 int reg, max; 43 unsigned int *fcount = FILE_FCOUNT(file); 44 45 max = num_var_ranges; 46 if (fcount == NULL) { 47 fcount = kzalloc(max * sizeof *fcount, GFP_KERNEL); 48 if (!fcount) 49 return -ENOMEM; 50 FILE_FCOUNT(file) = fcount; 51 } 52 if (!page) { 53 if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) 54 return -EINVAL; 55 base >>= PAGE_SHIFT; 56 size >>= PAGE_SHIFT; 57 } 58 reg = mtrr_add_page(base, size, type, 1); 59 if (reg >= 0) 60 ++fcount[reg]; 61 return reg; 62} 63 64static int 65mtrr_file_del(unsigned long base, unsigned long size, 66 struct file *file, int page) 67{ 68 int reg; 69 unsigned int *fcount = FILE_FCOUNT(file); 70 71 if (!page) { 72 if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) 73 return -EINVAL; 74 base >>= PAGE_SHIFT; 75 size >>= PAGE_SHIFT; 76 } 77 reg = mtrr_del_page(-1, base, size); 78 if (reg < 0) 79 return reg; 80 if (fcount == NULL) 81 return reg; 82 if (fcount[reg] < 1) 83 return -EINVAL; 84 --fcount[reg]; 85 return reg; 86} 87 88/* RED-PEN: seq_file can seek now. this is ignored. */ 89static ssize_t 90mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) 91/* Format of control line: 92 "base=%Lx size=%Lx type=%s" OR: 93 "disable=%d" 94*/ 95{ 96 int i, err; 97 unsigned long reg; 98 unsigned long long base, size; 99 char *ptr; 100 char line[LINE_SIZE]; 101 size_t linelen; 102 103 if (!capable(CAP_SYS_ADMIN)) 104 return -EPERM; 105 if (!len) 106 return -EINVAL; 107 memset(line, 0, LINE_SIZE); 108 if (len > LINE_SIZE) 109 len = LINE_SIZE; 110 if (copy_from_user(line, buf, len - 1)) 111 return -EFAULT; 112 linelen = strlen(line); 113 ptr = line + linelen - 1; 114 if (linelen && *ptr == '\n') 115 *ptr = '\0'; 116 if (!strncmp(line, "disable=", 8)) { 117 reg = simple_strtoul(line + 8, &ptr, 0); 118 err = mtrr_del_page(reg, 0, 0); 119 if (err < 0) 120 return err; 121 return len; 122 } 123 if (strncmp(line, "base=", 5)) 124 return -EINVAL; 125 base = simple_strtoull(line + 5, &ptr, 0); 126 for (; isspace(*ptr); ++ptr) ; 127 if (strncmp(ptr, "size=", 5)) 128 return -EINVAL; 129 size = simple_strtoull(ptr + 5, &ptr, 0); 130 if ((base & 0xfff) || (size & 0xfff)) 131 return -EINVAL; 132 for (; isspace(*ptr); ++ptr) ; 133 if (strncmp(ptr, "type=", 5)) 134 return -EINVAL; 135 ptr += 5; 136 for (; isspace(*ptr); ++ptr) ; 137 for (i = 0; i < MTRR_NUM_TYPES; ++i) { 138 if (strcmp(ptr, mtrr_strings[i])) 139 continue; 140 base >>= PAGE_SHIFT; 141 size >>= PAGE_SHIFT; 142 err = 143 mtrr_add_page((unsigned long) base, (unsigned long) size, i, 144 1); 145 if (err < 0) 146 return err; 147 return len; 148 } 149 return -EINVAL; 150} 151 152static long 153mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) 154{ 155 int err = 0; 156 mtrr_type type; 157 unsigned long size; 158 struct mtrr_sentry sentry; 159 struct mtrr_gentry gentry; 160 void __user *arg = (void __user *) __arg; 161 162 switch (cmd) { 163 case MTRRIOC_ADD_ENTRY: 164 case MTRRIOC_SET_ENTRY: 165 case MTRRIOC_DEL_ENTRY: 166 case MTRRIOC_KILL_ENTRY: 167 case MTRRIOC_ADD_PAGE_ENTRY: 168 case MTRRIOC_SET_PAGE_ENTRY: 169 case MTRRIOC_DEL_PAGE_ENTRY: 170 case MTRRIOC_KILL_PAGE_ENTRY: 171 if (copy_from_user(&sentry, arg, sizeof sentry)) 172 return -EFAULT; 173 break; 174 case MTRRIOC_GET_ENTRY: 175 case MTRRIOC_GET_PAGE_ENTRY: 176 if (copy_from_user(&gentry, arg, sizeof gentry)) 177 return -EFAULT; 178 break; 179#ifdef CONFIG_COMPAT 180 case MTRRIOC32_ADD_ENTRY: 181 case MTRRIOC32_SET_ENTRY: 182 case MTRRIOC32_DEL_ENTRY: 183 case MTRRIOC32_KILL_ENTRY: 184 case MTRRIOC32_ADD_PAGE_ENTRY: 185 case MTRRIOC32_SET_PAGE_ENTRY: 186 case MTRRIOC32_DEL_PAGE_ENTRY: 187 case MTRRIOC32_KILL_PAGE_ENTRY: { 188 struct mtrr_sentry32 __user *s32 = (struct mtrr_sentry32 __user *)__arg; 189 err = get_user(sentry.base, &s32->base); 190 err |= get_user(sentry.size, &s32->size); 191 err |= get_user(sentry.type, &s32->type); 192 if (err) 193 return err; 194 break; 195 } 196 case MTRRIOC32_GET_ENTRY: 197 case MTRRIOC32_GET_PAGE_ENTRY: { 198 struct mtrr_gentry32 __user *g32 = (struct mtrr_gentry32 __user *)__arg; 199 err = get_user(gentry.regnum, &g32->regnum); 200 err |= get_user(gentry.base, &g32->base); 201 err |= get_user(gentry.size, &g32->size); 202 err |= get_user(gentry.type, &g32->type); 203 if (err) 204 return err; 205 break; 206 } 207#endif 208 } 209 210 switch (cmd) { 211 default: 212 return -ENOTTY; 213 case MTRRIOC_ADD_ENTRY: 214#ifdef CONFIG_COMPAT 215 case MTRRIOC32_ADD_ENTRY: 216#endif 217 if (!capable(CAP_SYS_ADMIN)) 218 return -EPERM; 219 err = 220 mtrr_file_add(sentry.base, sentry.size, sentry.type, 1, 221 file, 0); 222 break; 223 case MTRRIOC_SET_ENTRY: 224#ifdef CONFIG_COMPAT 225 case MTRRIOC32_SET_ENTRY: 226#endif 227 if (!capable(CAP_SYS_ADMIN)) 228 return -EPERM; 229 err = mtrr_add(sentry.base, sentry.size, sentry.type, 0); 230 break; 231 case MTRRIOC_DEL_ENTRY: 232#ifdef CONFIG_COMPAT 233 case MTRRIOC32_DEL_ENTRY: 234#endif 235 if (!capable(CAP_SYS_ADMIN)) 236 return -EPERM; 237 err = mtrr_file_del(sentry.base, sentry.size, file, 0); 238 break; 239 case MTRRIOC_KILL_ENTRY: 240#ifdef CONFIG_COMPAT 241 case MTRRIOC32_KILL_ENTRY: 242#endif 243 if (!capable(CAP_SYS_ADMIN)) 244 return -EPERM; 245 err = mtrr_del(-1, sentry.base, sentry.size); 246 break; 247 case MTRRIOC_GET_ENTRY: 248#ifdef CONFIG_COMPAT 249 case MTRRIOC32_GET_ENTRY: 250#endif 251 if (gentry.regnum >= num_var_ranges) 252 return -EINVAL; 253 mtrr_if->get(gentry.regnum, &gentry.base, &size, &type); 254 255 /* Hide entries that go above 4GB */ 256 if (gentry.base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)) 257 || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))) 258 gentry.base = gentry.size = gentry.type = 0; 259 else { 260 gentry.base <<= PAGE_SHIFT; 261 gentry.size = size << PAGE_SHIFT; 262 gentry.type = type; 263 } 264 265 break; 266 case MTRRIOC_ADD_PAGE_ENTRY: 267#ifdef CONFIG_COMPAT 268 case MTRRIOC32_ADD_PAGE_ENTRY: 269#endif 270 if (!capable(CAP_SYS_ADMIN)) 271 return -EPERM; 272 err = 273 mtrr_file_add(sentry.base, sentry.size, sentry.type, 1, 274 file, 1); 275 break; 276 case MTRRIOC_SET_PAGE_ENTRY: 277#ifdef CONFIG_COMPAT 278 case MTRRIOC32_SET_PAGE_ENTRY: 279#endif 280 if (!capable(CAP_SYS_ADMIN)) 281 return -EPERM; 282 err = mtrr_add_page(sentry.base, sentry.size, sentry.type, 0); 283 break; 284 case MTRRIOC_DEL_PAGE_ENTRY: 285#ifdef CONFIG_COMPAT 286 case MTRRIOC32_DEL_PAGE_ENTRY: 287#endif 288 if (!capable(CAP_SYS_ADMIN)) 289 return -EPERM; 290 err = mtrr_file_del(sentry.base, sentry.size, file, 1); 291 break; 292 case MTRRIOC_KILL_PAGE_ENTRY: 293#ifdef CONFIG_COMPAT 294 case MTRRIOC32_KILL_PAGE_ENTRY: 295#endif 296 if (!capable(CAP_SYS_ADMIN)) 297 return -EPERM; 298 err = mtrr_del_page(-1, sentry.base, sentry.size); 299 break; 300 case MTRRIOC_GET_PAGE_ENTRY: 301#ifdef CONFIG_COMPAT 302 case MTRRIOC32_GET_PAGE_ENTRY: 303#endif 304 if (gentry.regnum >= num_var_ranges) 305 return -EINVAL; 306 mtrr_if->get(gentry.regnum, &gentry.base, &size, &type); 307 /* Hide entries that would overflow */ 308 if (size != (__typeof__(gentry.size))size) 309 gentry.base = gentry.size = gentry.type = 0; 310 else { 311 gentry.size = size; 312 gentry.type = type; 313 } 314 break; 315 } 316 317 if (err) 318 return err; 319 320 switch(cmd) { 321 case MTRRIOC_GET_ENTRY: 322 case MTRRIOC_GET_PAGE_ENTRY: 323 if (copy_to_user(arg, &gentry, sizeof gentry)) 324 err = -EFAULT; 325 break; 326#ifdef CONFIG_COMPAT 327 case MTRRIOC32_GET_ENTRY: 328 case MTRRIOC32_GET_PAGE_ENTRY: { 329 struct mtrr_gentry32 __user *g32 = (struct mtrr_gentry32 __user *)__arg; 330 err = put_user(gentry.base, &g32->base); 331 err |= put_user(gentry.size, &g32->size); 332 err |= put_user(gentry.regnum, &g32->regnum); 333 err |= put_user(gentry.type, &g32->type); 334 break; 335 } 336#endif 337 } 338 return err; 339} 340 341static int 342mtrr_close(struct inode *ino, struct file *file) 343{ 344 int i, max; 345 unsigned int *fcount = FILE_FCOUNT(file); 346 347 if (fcount != NULL) { 348 max = num_var_ranges; 349 for (i = 0; i < max; ++i) { 350 while (fcount[i] > 0) { 351 mtrr_del(i, 0, 0); 352 --fcount[i]; 353 } 354 } 355 kfree(fcount); 356 FILE_FCOUNT(file) = NULL; 357 } 358 return single_release(ino, file); 359} 360 361static int mtrr_seq_show(struct seq_file *seq, void *offset); 362 363static int mtrr_open(struct inode *inode, struct file *file) 364{ 365 if (!mtrr_if) 366 return -EIO; 367 if (!mtrr_if->get) 368 return -ENXIO; 369 return single_open(file, mtrr_seq_show, NULL); 370} 371 372static const struct file_operations mtrr_fops = { 373 .owner = THIS_MODULE, 374 .open = mtrr_open, 375 .read = seq_read, 376 .llseek = seq_lseek, 377 .write = mtrr_write, 378 .unlocked_ioctl = mtrr_ioctl, 379 .compat_ioctl = mtrr_ioctl, 380 .release = mtrr_close, 381}; 382 383 384static struct proc_dir_entry *proc_root_mtrr; 385 386 387static int mtrr_seq_show(struct seq_file *seq, void *offset) 388{ 389 char factor; 390 int i, max, len; 391 mtrr_type type; 392 unsigned long base, size; 393 394 len = 0; 395 max = num_var_ranges; 396 for (i = 0; i < max; i++) { 397 mtrr_if->get(i, &base, &size, &type); 398 if (size == 0) 399 usage_table[i] = 0; 400 else { 401 if (size < (0x100000 >> PAGE_SHIFT)) { 402 /* less than 1MB */ 403 factor = 'K'; 404 size <<= PAGE_SHIFT - 10; 405 } else { 406 factor = 'M'; 407 size >>= 20 - PAGE_SHIFT; 408 } 409 /* RED-PEN: base can be > 32bit */ 410 len += seq_printf(seq, 411 "reg%02i: base=0x%05lx000 (%4luMB), size=%4lu%cB: %s, count=%d\n", 412 i, base, base >> (20 - PAGE_SHIFT), size, factor, 413 mtrr_attrib_to_str(type), usage_table[i]); 414 } 415 } 416 return 0; 417} 418 419static int __init mtrr_if_init(void) 420{ 421 struct cpuinfo_x86 *c = &boot_cpu_data; 422 423 if ((!cpu_has(c, X86_FEATURE_MTRR)) && 424 (!cpu_has(c, X86_FEATURE_K6_MTRR)) && 425 (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) && 426 (!cpu_has(c, X86_FEATURE_CENTAUR_MCR))) 427 return -ENODEV; 428 429 proc_root_mtrr = 430 create_proc_entry("mtrr", S_IWUSR | S_IRUGO, &proc_root); 431 if (proc_root_mtrr) { 432 proc_root_mtrr->owner = THIS_MODULE; 433 proc_root_mtrr->proc_fops = &mtrr_fops; 434 } 435 return 0; 436} 437 438arch_initcall(mtrr_if_init); 439#endif /* CONFIG_PROC_FS */ 440