1 /* 2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include "linux/mm.h" 7 #include "asm/pgtable.h" 8 #include "asm/tlbflush.h" 9 #include "as-layout.h" 10 #include "mem_user.h" 11 #include "os.h" 12 #include "skas.h" 13 #include "tlb.h" 14 15 struct host_vm_change { 16 struct host_vm_op { 17 enum { NONE, MMAP, MUNMAP, MPROTECT } type; 18 union { 19 struct { 20 unsigned long addr; 21 unsigned long len; 22 unsigned int prot; 23 int fd; 24 __u64 offset; 25 } mmap; 26 struct { 27 unsigned long addr; 28 unsigned long len; 29 } munmap; 30 struct { 31 unsigned long addr; 32 unsigned long len; 33 unsigned int prot; 34 } mprotect; 35 } u; 36 } ops[1]; 37 int index; 38 struct mm_id *id; 39 void *data; 40 int force; 41 }; 42 43 #define INIT_HVC(mm, force) \ 44 ((struct host_vm_change) \ 45 { .ops = { { .type = NONE } }, \ 46 .id = &mm->context.id, \ 47 .data = NULL, \ 48 .index = 0, \ 49 .force = force }) 50 51 static int do_ops(struct host_vm_change *hvc, int end, 52 int finished) 53 { 54 struct host_vm_op *op; 55 int i, ret = 0; 56 57 for (i = 0; i < end && !ret; i++) { 58 op = &hvc->ops[i]; 59 switch(op->type) { 60 case MMAP: 61 ret = map(hvc->id, op->u.mmap.addr, op->u.mmap.len, 62 op->u.mmap.prot, op->u.mmap.fd, 63 op->u.mmap.offset, finished, &hvc->data); 64 break; 65 case MUNMAP: 66 ret = unmap(hvc->id, op->u.munmap.addr, 67 op->u.munmap.len, finished, &hvc->data); 68 break; 69 case MPROTECT: 70 ret = protect(hvc->id, op->u.mprotect.addr, 71 op->u.mprotect.len, op->u.mprotect.prot, 72 finished, &hvc->data); 73 break; 74 default: 75 printk(KERN_ERR "Unknown op type %d in do_ops\n", 76 op->type); 77 break; 78 } 79 } 80 81 return ret; 82 } 83 84 static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len, 85 unsigned int prot, struct host_vm_change *hvc) 86 { 87 __u64 offset; 88 struct host_vm_op *last; 89 int fd, ret = 0; 90 91 fd = phys_mapping(phys, &offset); 92 if (hvc->index != 0) { 93 last = &hvc->ops[hvc->index - 1]; 94 if ((last->type == MMAP) && 95 (last->u.mmap.addr + last->u.mmap.len == virt) && 96 (last->u.mmap.prot == prot) && (last->u.mmap.fd == fd) && 97 (last->u.mmap.offset + last->u.mmap.len == offset)) { 98 last->u.mmap.len += len; 99 return 0; 100 } 101 } 102 103 if (hvc->index == ARRAY_SIZE(hvc->ops)) { 104 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0); 105 hvc->index = 0; 106 } 107 108 hvc->ops[hvc->index++] = ((struct host_vm_op) 109 { .type = MMAP, 110 .u = { .mmap = { .addr = virt, 111 .len = len, 112 .prot = prot, 113 .fd = fd, 114 .offset = offset } 115 } }); 116 return ret; 117 } 118 119 static int add_munmap(unsigned long addr, unsigned long len, 120 struct host_vm_change *hvc) 121 { 122 struct host_vm_op *last; 123 int ret = 0; 124 125 if (hvc->index != 0) { 126 last = &hvc->ops[hvc->index - 1]; 127 if ((last->type == MUNMAP) && 128 (last->u.munmap.addr + last->u.mmap.len == addr)) { 129 last->u.munmap.len += len; 130 return 0; 131 } 132 } 133 134 if (hvc->index == ARRAY_SIZE(hvc->ops)) { 135 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0); 136 hvc->index = 0; 137 } 138 139 hvc->ops[hvc->index++] = ((struct host_vm_op) 140 { .type = MUNMAP, 141 .u = { .munmap = { .addr = addr, 142 .len = len } } }); 143 return ret; 144 } 145 146 static int add_mprotect(unsigned long addr, unsigned long len, 147 unsigned int prot, struct host_vm_change *hvc) 148 { 149 struct host_vm_op *last; 150 int ret = 0; 151 152 if (hvc->index != 0) { 153 last = &hvc->ops[hvc->index - 1]; 154 if ((last->type == MPROTECT) && 155 (last->u.mprotect.addr + last->u.mprotect.len == addr) && 156 (last->u.mprotect.prot == prot)) { 157 last->u.mprotect.len += len; 158 return 0; 159 } 160 } 161 162 if (hvc->index == ARRAY_SIZE(hvc->ops)) { 163 ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0); 164 hvc->index = 0; 165 } 166 167 hvc->ops[hvc->index++] = ((struct host_vm_op) 168 { .type = MPROTECT, 169 .u = { .mprotect = { .addr = addr, 170 .len = len, 171 .prot = prot } } }); 172 return ret; 173 } 174 175 #define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1)) 176 177 static inline int update_pte_range(pmd_t *pmd, unsigned long addr, 178 unsigned long end, 179 struct host_vm_change *hvc) 180 { 181 pte_t *pte; 182 int r, w, x, prot, ret = 0; 183 184 pte = pte_offset_kernel(pmd, addr); 185 do { 186 r = pte_read(*pte); 187 w = pte_write(*pte); 188 x = pte_exec(*pte); 189 if (!pte_young(*pte)) { 190 r = 0; 191 w = 0; 192 } else if (!pte_dirty(*pte)) { 193 w = 0; 194 } 195 prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) | 196 (x ? UM_PROT_EXEC : 0)); 197 if (hvc->force || pte_newpage(*pte)) { 198 if (pte_present(*pte)) 199 ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK, 200 PAGE_SIZE, prot, hvc); 201 else ret = add_munmap(addr, PAGE_SIZE, hvc); 202 } 203 else if (pte_newprot(*pte)) 204 ret = add_mprotect(addr, PAGE_SIZE, prot, hvc); 205 *pte = pte_mkuptodate(*pte); 206 } while (pte++, addr += PAGE_SIZE, ((addr != end) && !ret)); 207 return ret; 208 } 209 210 static inline int update_pmd_range(pud_t *pud, unsigned long addr, 211 unsigned long end, 212 struct host_vm_change *hvc) 213 { 214 pmd_t *pmd; 215 unsigned long next; 216 int ret = 0; 217 218 pmd = pmd_offset(pud, addr); 219 do { 220 next = pmd_addr_end(addr, end); 221 if (!pmd_present(*pmd)) { 222 if (hvc->force || pmd_newpage(*pmd)) { 223 ret = add_munmap(addr, next - addr, hvc); 224 pmd_mkuptodate(*pmd); 225 } 226 } 227 else ret = update_pte_range(pmd, addr, next, hvc); 228 } while (pmd++, addr = next, ((addr != end) && !ret)); 229 return ret; 230 } 231 232 static inline int update_pud_range(pgd_t *pgd, unsigned long addr, 233 unsigned long end, 234 struct host_vm_change *hvc) 235 { 236 pud_t *pud; 237 unsigned long next; 238 int ret = 0; 239 240 pud = pud_offset(pgd, addr); 241 do { 242 next = pud_addr_end(addr, end); 243 if (!pud_present(*pud)) { 244 if (hvc->force || pud_newpage(*pud)) { 245 ret = add_munmap(addr, next - addr, hvc); 246 pud_mkuptodate(*pud); 247 } 248 } 249 else ret = update_pmd_range(pud, addr, next, hvc); 250 } while (pud++, addr = next, ((addr != end) && !ret)); 251 return ret; 252 } 253 254 void fix_range_common(struct mm_struct *mm, unsigned long start_addr, 255 unsigned long end_addr, int force) 256 { 257 pgd_t *pgd; 258 struct host_vm_change hvc; 259 unsigned long addr = start_addr, next; 260 int ret = 0; 261 262 hvc = INIT_HVC(mm, force); 263 pgd = pgd_offset(mm, addr); 264 do { 265 next = pgd_addr_end(addr, end_addr); 266 if (!pgd_present(*pgd)) { 267 if (force || pgd_newpage(*pgd)) { 268 ret = add_munmap(addr, next - addr, &hvc); 269 pgd_mkuptodate(*pgd); 270 } 271 } 272 else ret = update_pud_range(pgd, addr, next, &hvc); 273 } while (pgd++, addr = next, ((addr != end_addr) && !ret)); 274 275 if (!ret) 276 ret = do_ops(&hvc, hvc.index, 1); 277 278 /* This is not an else because ret is modified above */ 279 if (ret) { 280 printk(KERN_ERR "fix_range_common: failed, killing current " 281 "process\n"); 282 force_sig(SIGKILL, current); 283 } 284 } 285 286 int flush_tlb_kernel_range_common(unsigned long start, unsigned long end) 287 { 288 struct mm_struct *mm; 289 pgd_t *pgd; 290 pud_t *pud; 291 pmd_t *pmd; 292 pte_t *pte; 293 unsigned long addr, last; 294 int updated = 0, err; 295 296 mm = &init_mm; 297 for (addr = start; addr < end;) { 298 pgd = pgd_offset(mm, addr); 299 if (!pgd_present(*pgd)) { 300 last = ADD_ROUND(addr, PGDIR_SIZE); 301 if (last > end) 302 last = end; 303 if (pgd_newpage(*pgd)) { 304 updated = 1; 305 err = os_unmap_memory((void *) addr, 306 last - addr); 307 if (err < 0) 308 panic("munmap failed, errno = %d\n", 309 -err); 310 } 311 addr = last; 312 continue; 313 } 314 315 pud = pud_offset(pgd, addr); 316 if (!pud_present(*pud)) { 317 last = ADD_ROUND(addr, PUD_SIZE); 318 if (last > end) 319 last = end; 320 if (pud_newpage(*pud)) { 321 updated = 1; 322 err = os_unmap_memory((void *) addr, 323 last - addr); 324 if (err < 0) 325 panic("munmap failed, errno = %d\n", 326 -err); 327 } 328 addr = last; 329 continue; 330 } 331 332 pmd = pmd_offset(pud, addr); 333 if (!pmd_present(*pmd)) { 334 last = ADD_ROUND(addr, PMD_SIZE); 335 if (last > end) 336 last = end; 337 if (pmd_newpage(*pmd)) { 338 updated = 1; 339 err = os_unmap_memory((void *) addr, 340 last - addr); 341 if (err < 0) 342 panic("munmap failed, errno = %d\n", 343 -err); 344 } 345 addr = last; 346 continue; 347 } 348 349 pte = pte_offset_kernel(pmd, addr); 350 if (!pte_present(*pte) || pte_newpage(*pte)) { 351 updated = 1; 352 err = os_unmap_memory((void *) addr, 353 PAGE_SIZE); 354 if (err < 0) 355 panic("munmap failed, errno = %d\n", 356 -err); 357 if (pte_present(*pte)) 358 map_memory(addr, 359 pte_val(*pte) & PAGE_MASK, 360 PAGE_SIZE, 1, 1, 1); 361 } 362 else if (pte_newprot(*pte)) { 363 updated = 1; 364 os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1); 365 } 366 addr += PAGE_SIZE; 367 } 368 return updated; 369 } 370 371 void flush_tlb_page(struct vm_area_struct *vma, unsigned long address) 372 { 373 pgd_t *pgd; 374 pud_t *pud; 375 pmd_t *pmd; 376 pte_t *pte; 377 struct mm_struct *mm = vma->vm_mm; 378 void *flush = NULL; 379 int r, w, x, prot, err = 0; 380 struct mm_id *mm_id; 381 382 address &= PAGE_MASK; 383 pgd = pgd_offset(mm, address); 384 if (!pgd_present(*pgd)) 385 goto kill; 386 387 pud = pud_offset(pgd, address); 388 if (!pud_present(*pud)) 389 goto kill; 390 391 pmd = pmd_offset(pud, address); 392 if (!pmd_present(*pmd)) 393 goto kill; 394 395 pte = pte_offset_kernel(pmd, address); 396 397 r = pte_read(*pte); 398 w = pte_write(*pte); 399 x = pte_exec(*pte); 400 if (!pte_young(*pte)) { 401 r = 0; 402 w = 0; 403 } else if (!pte_dirty(*pte)) { 404 w = 0; 405 } 406 407 mm_id = &mm->context.id; 408 prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) | 409 (x ? UM_PROT_EXEC : 0)); 410 if (pte_newpage(*pte)) { 411 if (pte_present(*pte)) { 412 unsigned long long offset; 413 int fd; 414 415 fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset); 416 err = map(mm_id, address, PAGE_SIZE, prot, fd, offset, 417 1, &flush); 418 } 419 else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush); 420 } 421 else if (pte_newprot(*pte)) 422 err = protect(mm_id, address, PAGE_SIZE, prot, 1, &flush); 423 424 if (err) 425 goto kill; 426 427 *pte = pte_mkuptodate(*pte); 428 429 return; 430 431 kill: 432 printk(KERN_ERR "Failed to flush page for address 0x%lx\n", address); 433 force_sig(SIGKILL, current); 434 } 435 436 pgd_t *pgd_offset_proc(struct mm_struct *mm, unsigned long address) 437 { 438 return pgd_offset(mm, address); 439 } 440 441 pud_t *pud_offset_proc(pgd_t *pgd, unsigned long address) 442 { 443 return pud_offset(pgd, address); 444 } 445 446 pmd_t *pmd_offset_proc(pud_t *pud, unsigned long address) 447 { 448 return pmd_offset(pud, address); 449 } 450 451 pte_t *pte_offset_proc(pmd_t *pmd, unsigned long address) 452 { 453 return pte_offset_kernel(pmd, address); 454 } 455 456 pte_t *addr_pte(struct task_struct *task, unsigned long addr) 457 { 458 pgd_t *pgd = pgd_offset(task->mm, addr); 459 pud_t *pud = pud_offset(pgd, addr); 460 pmd_t *pmd = pmd_offset(pud, addr); 461 462 return pte_offset_map(pmd, addr); 463 } 464 465 void flush_tlb_all(void) 466 { 467 flush_tlb_mm(current->mm); 468 } 469 470 void flush_tlb_kernel_range(unsigned long start, unsigned long end) 471 { 472 flush_tlb_kernel_range_common(start, end); 473 } 474 475 void flush_tlb_kernel_vm(void) 476 { 477 flush_tlb_kernel_range_common(start_vm, end_vm); 478 } 479 480 void __flush_tlb_one(unsigned long addr) 481 { 482 flush_tlb_kernel_range_common(addr, addr + PAGE_SIZE); 483 } 484 485 static void fix_range(struct mm_struct *mm, unsigned long start_addr, 486 unsigned long end_addr, int force) 487 { 488 if (!proc_mm && (end_addr > STUB_START)) 489 end_addr = STUB_START; 490 491 fix_range_common(mm, start_addr, end_addr, force); 492 } 493 494 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, 495 unsigned long end) 496 { 497 if (vma->vm_mm == NULL) 498 flush_tlb_kernel_range_common(start, end); 499 else fix_range(vma->vm_mm, start, end, 0); 500 } 501 502 void flush_tlb_mm(struct mm_struct *mm) 503 { 504 unsigned long end; 505 506 /* 507 * Don't bother flushing if this address space is about to be 508 * destroyed. 509 */ 510 if (atomic_read(&mm->mm_users) == 0) 511 return; 512 513 end = proc_mm ? task_size : STUB_START; 514 fix_range(mm, 0, end, 0); 515 } 516 517 void force_flush_all(void) 518 { 519 struct mm_struct *mm = current->mm; 520 struct vm_area_struct *vma = mm->mmap; 521 522 while (vma != NULL) { 523 fix_range(mm, vma->vm_start, vma->vm_end, 1); 524 vma = vma->vm_next; 525 } 526 } 527