1 #include <linux/mm.h> 2 #include <linux/vmacache.h> 3 #include <linux/hugetlb.h> 4 #include <linux/huge_mm.h> 5 #include <linux/mount.h> 6 #include <linux/seq_file.h> 7 #include <linux/highmem.h> 8 #include <linux/ptrace.h> 9 #include <linux/slab.h> 10 #include <linux/pagemap.h> 11 #include <linux/mempolicy.h> 12 #include <linux/rmap.h> 13 #include <linux/swap.h> 14 #include <linux/swapops.h> 15 #include <linux/mmu_notifier.h> 16 17 #include <asm/elf.h> 18 #include <asm/uaccess.h> 19 #include <asm/tlbflush.h> 20 #include "internal.h" 21 22 void task_mem(struct seq_file *m, struct mm_struct *mm) 23 { 24 unsigned long data, text, lib, swap; 25 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 26 27 /* 28 * Note: to minimize their overhead, mm maintains hiwater_vm and 29 * hiwater_rss only when about to *lower* total_vm or rss. Any 30 * collector of these hiwater stats must therefore get total_vm 31 * and rss too, which will usually be the higher. Barriers? not 32 * worth the effort, such snapshots can always be inconsistent. 33 */ 34 hiwater_vm = total_vm = mm->total_vm; 35 if (hiwater_vm < mm->hiwater_vm) 36 hiwater_vm = mm->hiwater_vm; 37 hiwater_rss = total_rss = get_mm_rss(mm); 38 if (hiwater_rss < mm->hiwater_rss) 39 hiwater_rss = mm->hiwater_rss; 40 41 data = mm->total_vm - mm->shared_vm - mm->stack_vm; 42 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; 43 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; 44 swap = get_mm_counter(mm, MM_SWAPENTS); 45 seq_printf(m, 46 "VmPeak:\t%8lu kB\n" 47 "VmSize:\t%8lu kB\n" 48 "VmLck:\t%8lu kB\n" 49 "VmPin:\t%8lu kB\n" 50 "VmHWM:\t%8lu kB\n" 51 "VmRSS:\t%8lu kB\n" 52 "VmData:\t%8lu kB\n" 53 "VmStk:\t%8lu kB\n" 54 "VmExe:\t%8lu kB\n" 55 "VmLib:\t%8lu kB\n" 56 "VmPTE:\t%8lu kB\n" 57 "VmSwap:\t%8lu kB\n", 58 hiwater_vm << (PAGE_SHIFT-10), 59 total_vm << (PAGE_SHIFT-10), 60 mm->locked_vm << (PAGE_SHIFT-10), 61 mm->pinned_vm << (PAGE_SHIFT-10), 62 hiwater_rss << (PAGE_SHIFT-10), 63 total_rss << (PAGE_SHIFT-10), 64 data << (PAGE_SHIFT-10), 65 mm->stack_vm << (PAGE_SHIFT-10), text, lib, 66 (PTRS_PER_PTE * sizeof(pte_t) * 67 atomic_long_read(&mm->nr_ptes)) >> 10, 68 swap << (PAGE_SHIFT-10)); 69 } 70 71 unsigned long task_vsize(struct mm_struct *mm) 72 { 73 return PAGE_SIZE * mm->total_vm; 74 } 75 76 unsigned long task_statm(struct mm_struct *mm, 77 unsigned long *shared, unsigned long *text, 78 unsigned long *data, unsigned long *resident) 79 { 80 *shared = get_mm_counter(mm, MM_FILEPAGES); 81 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 82 >> PAGE_SHIFT; 83 *data = mm->total_vm - mm->shared_vm; 84 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 85 return mm->total_vm; 86 } 87 88 #ifdef CONFIG_NUMA 89 /* 90 * Save get_task_policy() for show_numa_map(). 91 */ 92 static void hold_task_mempolicy(struct proc_maps_private *priv) 93 { 94 struct task_struct *task = priv->task; 95 96 task_lock(task); 97 priv->task_mempolicy = get_task_policy(task); 98 mpol_get(priv->task_mempolicy); 99 task_unlock(task); 100 } 101 static void release_task_mempolicy(struct proc_maps_private *priv) 102 { 103 mpol_put(priv->task_mempolicy); 104 } 105 #else 106 static void hold_task_mempolicy(struct proc_maps_private *priv) 107 { 108 } 109 static void release_task_mempolicy(struct proc_maps_private *priv) 110 { 111 } 112 #endif 113 114 static void vma_stop(struct proc_maps_private *priv) 115 { 116 struct mm_struct *mm = priv->mm; 117 118 release_task_mempolicy(priv); 119 up_read(&mm->mmap_sem); 120 mmput(mm); 121 } 122 123 static struct vm_area_struct * 124 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma) 125 { 126 if (vma == priv->tail_vma) 127 return NULL; 128 return vma->vm_next ?: priv->tail_vma; 129 } 130 131 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma) 132 { 133 if (m->count < m->size) /* vma is copied successfully */ 134 m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL; 135 } 136 137 static void *m_start(struct seq_file *m, loff_t *ppos) 138 { 139 struct proc_maps_private *priv = m->private; 140 unsigned long last_addr = m->version; 141 struct mm_struct *mm; 142 struct vm_area_struct *vma; 143 unsigned int pos = *ppos; 144 145 /* See m_cache_vma(). Zero at the start or after lseek. */ 146 if (last_addr == -1UL) 147 return NULL; 148 149 priv->task = get_proc_task(priv->inode); 150 if (!priv->task) 151 return ERR_PTR(-ESRCH); 152 153 mm = priv->mm; 154 if (!mm || !atomic_inc_not_zero(&mm->mm_users)) 155 return NULL; 156 157 down_read(&mm->mmap_sem); 158 hold_task_mempolicy(priv); 159 priv->tail_vma = get_gate_vma(mm); 160 161 if (last_addr) { 162 vma = find_vma(mm, last_addr); 163 if (vma && (vma = m_next_vma(priv, vma))) 164 return vma; 165 } 166 167 m->version = 0; 168 if (pos < mm->map_count) { 169 for (vma = mm->mmap; pos; pos--) { 170 m->version = vma->vm_start; 171 vma = vma->vm_next; 172 } 173 return vma; 174 } 175 176 /* we do not bother to update m->version in this case */ 177 if (pos == mm->map_count && priv->tail_vma) 178 return priv->tail_vma; 179 180 vma_stop(priv); 181 return NULL; 182 } 183 184 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 185 { 186 struct proc_maps_private *priv = m->private; 187 struct vm_area_struct *next; 188 189 (*pos)++; 190 next = m_next_vma(priv, v); 191 if (!next) 192 vma_stop(priv); 193 return next; 194 } 195 196 static void m_stop(struct seq_file *m, void *v) 197 { 198 struct proc_maps_private *priv = m->private; 199 200 if (!IS_ERR_OR_NULL(v)) 201 vma_stop(priv); 202 if (priv->task) { 203 put_task_struct(priv->task); 204 priv->task = NULL; 205 } 206 } 207 208 static int proc_maps_open(struct inode *inode, struct file *file, 209 const struct seq_operations *ops, int psize) 210 { 211 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 212 213 if (!priv) 214 return -ENOMEM; 215 216 priv->inode = inode; 217 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 218 if (IS_ERR(priv->mm)) { 219 int err = PTR_ERR(priv->mm); 220 221 seq_release_private(inode, file); 222 return err; 223 } 224 225 return 0; 226 } 227 228 static int proc_map_release(struct inode *inode, struct file *file) 229 { 230 struct seq_file *seq = file->private_data; 231 struct proc_maps_private *priv = seq->private; 232 233 if (priv->mm) 234 mmdrop(priv->mm); 235 236 return seq_release_private(inode, file); 237 } 238 239 static int do_maps_open(struct inode *inode, struct file *file, 240 const struct seq_operations *ops) 241 { 242 return proc_maps_open(inode, file, ops, 243 sizeof(struct proc_maps_private)); 244 } 245 246 static pid_t pid_of_stack(struct proc_maps_private *priv, 247 struct vm_area_struct *vma, bool is_pid) 248 { 249 struct inode *inode = priv->inode; 250 struct task_struct *task; 251 pid_t ret = 0; 252 253 rcu_read_lock(); 254 task = pid_task(proc_pid(inode), PIDTYPE_PID); 255 if (task) { 256 task = task_of_stack(task, vma, is_pid); 257 if (task) 258 ret = task_pid_nr_ns(task, inode->i_sb->s_fs_info); 259 } 260 rcu_read_unlock(); 261 262 return ret; 263 } 264 265 static void 266 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid) 267 { 268 struct mm_struct *mm = vma->vm_mm; 269 struct file *file = vma->vm_file; 270 struct proc_maps_private *priv = m->private; 271 vm_flags_t flags = vma->vm_flags; 272 unsigned long ino = 0; 273 unsigned long long pgoff = 0; 274 unsigned long start, end; 275 dev_t dev = 0; 276 const char *name = NULL; 277 278 if (file) { 279 struct inode *inode = file_inode(vma->vm_file); 280 dev = inode->i_sb->s_dev; 281 ino = inode->i_ino; 282 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 283 } 284 285 /* We don't show the stack guard page in /proc/maps */ 286 start = vma->vm_start; 287 if (stack_guard_page_start(vma, start)) 288 start += PAGE_SIZE; 289 end = vma->vm_end; 290 if (stack_guard_page_end(vma, end)) 291 end -= PAGE_SIZE; 292 293 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 294 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ", 295 start, 296 end, 297 flags & VM_READ ? 'r' : '-', 298 flags & VM_WRITE ? 'w' : '-', 299 flags & VM_EXEC ? 'x' : '-', 300 flags & VM_MAYSHARE ? 's' : 'p', 301 pgoff, 302 MAJOR(dev), MINOR(dev), ino); 303 304 /* 305 * Print the dentry name for named mappings, and a 306 * special [heap] marker for the heap: 307 */ 308 if (file) { 309 seq_pad(m, ' '); 310 seq_path(m, &file->f_path, "\n"); 311 goto done; 312 } 313 314 if (vma->vm_ops && vma->vm_ops->name) { 315 name = vma->vm_ops->name(vma); 316 if (name) 317 goto done; 318 } 319 320 name = arch_vma_name(vma); 321 if (!name) { 322 pid_t tid; 323 324 if (!mm) { 325 name = "[vdso]"; 326 goto done; 327 } 328 329 if (vma->vm_start <= mm->brk && 330 vma->vm_end >= mm->start_brk) { 331 name = "[heap]"; 332 goto done; 333 } 334 335 tid = pid_of_stack(priv, vma, is_pid); 336 if (tid != 0) { 337 /* 338 * Thread stack in /proc/PID/task/TID/maps or 339 * the main process stack. 340 */ 341 if (!is_pid || (vma->vm_start <= mm->start_stack && 342 vma->vm_end >= mm->start_stack)) { 343 name = "[stack]"; 344 } else { 345 /* Thread stack in /proc/PID/maps */ 346 seq_pad(m, ' '); 347 seq_printf(m, "[stack:%d]", tid); 348 } 349 } 350 } 351 352 done: 353 if (name) { 354 seq_pad(m, ' '); 355 seq_puts(m, name); 356 } 357 seq_putc(m, '\n'); 358 } 359 360 static int show_map(struct seq_file *m, void *v, int is_pid) 361 { 362 show_map_vma(m, v, is_pid); 363 m_cache_vma(m, v); 364 return 0; 365 } 366 367 static int show_pid_map(struct seq_file *m, void *v) 368 { 369 return show_map(m, v, 1); 370 } 371 372 static int show_tid_map(struct seq_file *m, void *v) 373 { 374 return show_map(m, v, 0); 375 } 376 377 static const struct seq_operations proc_pid_maps_op = { 378 .start = m_start, 379 .next = m_next, 380 .stop = m_stop, 381 .show = show_pid_map 382 }; 383 384 static const struct seq_operations proc_tid_maps_op = { 385 .start = m_start, 386 .next = m_next, 387 .stop = m_stop, 388 .show = show_tid_map 389 }; 390 391 static int pid_maps_open(struct inode *inode, struct file *file) 392 { 393 return do_maps_open(inode, file, &proc_pid_maps_op); 394 } 395 396 static int tid_maps_open(struct inode *inode, struct file *file) 397 { 398 return do_maps_open(inode, file, &proc_tid_maps_op); 399 } 400 401 const struct file_operations proc_pid_maps_operations = { 402 .open = pid_maps_open, 403 .read = seq_read, 404 .llseek = seq_lseek, 405 .release = proc_map_release, 406 }; 407 408 const struct file_operations proc_tid_maps_operations = { 409 .open = tid_maps_open, 410 .read = seq_read, 411 .llseek = seq_lseek, 412 .release = proc_map_release, 413 }; 414 415 /* 416 * Proportional Set Size(PSS): my share of RSS. 417 * 418 * PSS of a process is the count of pages it has in memory, where each 419 * page is divided by the number of processes sharing it. So if a 420 * process has 1000 pages all to itself, and 1000 shared with one other 421 * process, its PSS will be 1500. 422 * 423 * To keep (accumulated) division errors low, we adopt a 64bit 424 * fixed-point pss counter to minimize division errors. So (pss >> 425 * PSS_SHIFT) would be the real byte count. 426 * 427 * A shift of 12 before division means (assuming 4K page size): 428 * - 1M 3-user-pages add up to 8KB errors; 429 * - supports mapcount up to 2^24, or 16M; 430 * - supports PSS up to 2^52 bytes, or 4PB. 431 */ 432 #define PSS_SHIFT 12 433 434 #ifdef CONFIG_PROC_PAGE_MONITOR 435 struct mem_size_stats { 436 struct vm_area_struct *vma; 437 unsigned long resident; 438 unsigned long shared_clean; 439 unsigned long shared_dirty; 440 unsigned long private_clean; 441 unsigned long private_dirty; 442 unsigned long referenced; 443 unsigned long anonymous; 444 unsigned long anonymous_thp; 445 unsigned long swap; 446 unsigned long nonlinear; 447 u64 pss; 448 }; 449 450 451 static void smaps_pte_entry(pte_t ptent, unsigned long addr, 452 unsigned long ptent_size, struct mm_walk *walk) 453 { 454 struct mem_size_stats *mss = walk->private; 455 struct vm_area_struct *vma = mss->vma; 456 pgoff_t pgoff = linear_page_index(vma, addr); 457 struct page *page = NULL; 458 int mapcount; 459 460 if (pte_present(ptent)) { 461 page = vm_normal_page(vma, addr, ptent); 462 } else if (is_swap_pte(ptent)) { 463 swp_entry_t swpent = pte_to_swp_entry(ptent); 464 465 if (!non_swap_entry(swpent)) 466 mss->swap += ptent_size; 467 else if (is_migration_entry(swpent)) 468 page = migration_entry_to_page(swpent); 469 } else if (pte_file(ptent)) { 470 if (pte_to_pgoff(ptent) != pgoff) 471 mss->nonlinear += ptent_size; 472 } 473 474 if (!page) 475 return; 476 477 if (PageAnon(page)) 478 mss->anonymous += ptent_size; 479 480 if (page->index != pgoff) 481 mss->nonlinear += ptent_size; 482 483 mss->resident += ptent_size; 484 /* Accumulate the size in pages that have been accessed. */ 485 if (pte_young(ptent) || PageReferenced(page)) 486 mss->referenced += ptent_size; 487 mapcount = page_mapcount(page); 488 if (mapcount >= 2) { 489 if (pte_dirty(ptent) || PageDirty(page)) 490 mss->shared_dirty += ptent_size; 491 else 492 mss->shared_clean += ptent_size; 493 mss->pss += (ptent_size << PSS_SHIFT) / mapcount; 494 } else { 495 if (pte_dirty(ptent) || PageDirty(page)) 496 mss->private_dirty += ptent_size; 497 else 498 mss->private_clean += ptent_size; 499 mss->pss += (ptent_size << PSS_SHIFT); 500 } 501 } 502 503 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 504 struct mm_walk *walk) 505 { 506 struct mem_size_stats *mss = walk->private; 507 struct vm_area_struct *vma = mss->vma; 508 pte_t *pte; 509 spinlock_t *ptl; 510 511 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { 512 smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk); 513 spin_unlock(ptl); 514 mss->anonymous_thp += HPAGE_PMD_SIZE; 515 return 0; 516 } 517 518 if (pmd_trans_unstable(pmd)) 519 return 0; 520 /* 521 * The mmap_sem held all the way back in m_start() is what 522 * keeps khugepaged out of here and from collapsing things 523 * in here. 524 */ 525 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 526 for (; addr != end; pte++, addr += PAGE_SIZE) 527 smaps_pte_entry(*pte, addr, PAGE_SIZE, walk); 528 pte_unmap_unlock(pte - 1, ptl); 529 cond_resched(); 530 return 0; 531 } 532 533 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 534 { 535 /* 536 * Don't forget to update Documentation/ on changes. 537 */ 538 static const char mnemonics[BITS_PER_LONG][2] = { 539 /* 540 * In case if we meet a flag we don't know about. 541 */ 542 [0 ... (BITS_PER_LONG-1)] = "??", 543 544 [ilog2(VM_READ)] = "rd", 545 [ilog2(VM_WRITE)] = "wr", 546 [ilog2(VM_EXEC)] = "ex", 547 [ilog2(VM_SHARED)] = "sh", 548 [ilog2(VM_MAYREAD)] = "mr", 549 [ilog2(VM_MAYWRITE)] = "mw", 550 [ilog2(VM_MAYEXEC)] = "me", 551 [ilog2(VM_MAYSHARE)] = "ms", 552 [ilog2(VM_GROWSDOWN)] = "gd", 553 [ilog2(VM_PFNMAP)] = "pf", 554 [ilog2(VM_DENYWRITE)] = "dw", 555 #ifdef CONFIG_X86_INTEL_MPX 556 [ilog2(VM_MPX)] = "mp", 557 #endif 558 [ilog2(VM_LOCKED)] = "lo", 559 [ilog2(VM_IO)] = "io", 560 [ilog2(VM_SEQ_READ)] = "sr", 561 [ilog2(VM_RAND_READ)] = "rr", 562 [ilog2(VM_DONTCOPY)] = "dc", 563 [ilog2(VM_DONTEXPAND)] = "de", 564 [ilog2(VM_ACCOUNT)] = "ac", 565 [ilog2(VM_NORESERVE)] = "nr", 566 [ilog2(VM_HUGETLB)] = "ht", 567 [ilog2(VM_NONLINEAR)] = "nl", 568 [ilog2(VM_ARCH_1)] = "ar", 569 [ilog2(VM_DONTDUMP)] = "dd", 570 #ifdef CONFIG_MEM_SOFT_DIRTY 571 [ilog2(VM_SOFTDIRTY)] = "sd", 572 #endif 573 [ilog2(VM_MIXEDMAP)] = "mm", 574 [ilog2(VM_HUGEPAGE)] = "hg", 575 [ilog2(VM_NOHUGEPAGE)] = "nh", 576 [ilog2(VM_MERGEABLE)] = "mg", 577 }; 578 size_t i; 579 580 seq_puts(m, "VmFlags: "); 581 for (i = 0; i < BITS_PER_LONG; i++) { 582 if (vma->vm_flags & (1UL << i)) { 583 seq_printf(m, "%c%c ", 584 mnemonics[i][0], mnemonics[i][1]); 585 } 586 } 587 seq_putc(m, '\n'); 588 } 589 590 static int show_smap(struct seq_file *m, void *v, int is_pid) 591 { 592 struct vm_area_struct *vma = v; 593 struct mem_size_stats mss; 594 struct mm_walk smaps_walk = { 595 .pmd_entry = smaps_pte_range, 596 .mm = vma->vm_mm, 597 .private = &mss, 598 }; 599 600 memset(&mss, 0, sizeof mss); 601 mss.vma = vma; 602 /* mmap_sem is held in m_start */ 603 if (vma->vm_mm && !is_vm_hugetlb_page(vma)) 604 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk); 605 606 show_map_vma(m, vma, is_pid); 607 608 seq_printf(m, 609 "Size: %8lu kB\n" 610 "Rss: %8lu kB\n" 611 "Pss: %8lu kB\n" 612 "Shared_Clean: %8lu kB\n" 613 "Shared_Dirty: %8lu kB\n" 614 "Private_Clean: %8lu kB\n" 615 "Private_Dirty: %8lu kB\n" 616 "Referenced: %8lu kB\n" 617 "Anonymous: %8lu kB\n" 618 "AnonHugePages: %8lu kB\n" 619 "Swap: %8lu kB\n" 620 "KernelPageSize: %8lu kB\n" 621 "MMUPageSize: %8lu kB\n" 622 "Locked: %8lu kB\n", 623 (vma->vm_end - vma->vm_start) >> 10, 624 mss.resident >> 10, 625 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)), 626 mss.shared_clean >> 10, 627 mss.shared_dirty >> 10, 628 mss.private_clean >> 10, 629 mss.private_dirty >> 10, 630 mss.referenced >> 10, 631 mss.anonymous >> 10, 632 mss.anonymous_thp >> 10, 633 mss.swap >> 10, 634 vma_kernel_pagesize(vma) >> 10, 635 vma_mmu_pagesize(vma) >> 10, 636 (vma->vm_flags & VM_LOCKED) ? 637 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0); 638 639 if (vma->vm_flags & VM_NONLINEAR) 640 seq_printf(m, "Nonlinear: %8lu kB\n", 641 mss.nonlinear >> 10); 642 643 show_smap_vma_flags(m, vma); 644 m_cache_vma(m, vma); 645 return 0; 646 } 647 648 static int show_pid_smap(struct seq_file *m, void *v) 649 { 650 return show_smap(m, v, 1); 651 } 652 653 static int show_tid_smap(struct seq_file *m, void *v) 654 { 655 return show_smap(m, v, 0); 656 } 657 658 static const struct seq_operations proc_pid_smaps_op = { 659 .start = m_start, 660 .next = m_next, 661 .stop = m_stop, 662 .show = show_pid_smap 663 }; 664 665 static const struct seq_operations proc_tid_smaps_op = { 666 .start = m_start, 667 .next = m_next, 668 .stop = m_stop, 669 .show = show_tid_smap 670 }; 671 672 static int pid_smaps_open(struct inode *inode, struct file *file) 673 { 674 return do_maps_open(inode, file, &proc_pid_smaps_op); 675 } 676 677 static int tid_smaps_open(struct inode *inode, struct file *file) 678 { 679 return do_maps_open(inode, file, &proc_tid_smaps_op); 680 } 681 682 const struct file_operations proc_pid_smaps_operations = { 683 .open = pid_smaps_open, 684 .read = seq_read, 685 .llseek = seq_lseek, 686 .release = proc_map_release, 687 }; 688 689 const struct file_operations proc_tid_smaps_operations = { 690 .open = tid_smaps_open, 691 .read = seq_read, 692 .llseek = seq_lseek, 693 .release = proc_map_release, 694 }; 695 696 /* 697 * We do not want to have constant page-shift bits sitting in 698 * pagemap entries and are about to reuse them some time soon. 699 * 700 * Here's the "migration strategy": 701 * 1. when the system boots these bits remain what they are, 702 * but a warning about future change is printed in log; 703 * 2. once anyone clears soft-dirty bits via clear_refs file, 704 * these flag is set to denote, that user is aware of the 705 * new API and those page-shift bits change their meaning. 706 * The respective warning is printed in dmesg; 707 * 3. In a couple of releases we will remove all the mentions 708 * of page-shift in pagemap entries. 709 */ 710 711 static bool soft_dirty_cleared __read_mostly; 712 713 enum clear_refs_types { 714 CLEAR_REFS_ALL = 1, 715 CLEAR_REFS_ANON, 716 CLEAR_REFS_MAPPED, 717 CLEAR_REFS_SOFT_DIRTY, 718 CLEAR_REFS_LAST, 719 }; 720 721 struct clear_refs_private { 722 struct vm_area_struct *vma; 723 enum clear_refs_types type; 724 }; 725 726 static inline void clear_soft_dirty(struct vm_area_struct *vma, 727 unsigned long addr, pte_t *pte) 728 { 729 #ifdef CONFIG_MEM_SOFT_DIRTY 730 /* 731 * The soft-dirty tracker uses #PF-s to catch writes 732 * to pages, so write-protect the pte as well. See the 733 * Documentation/vm/soft-dirty.txt for full description 734 * of how soft-dirty works. 735 */ 736 pte_t ptent = *pte; 737 738 if (pte_present(ptent)) { 739 ptent = pte_wrprotect(ptent); 740 ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY); 741 } else if (is_swap_pte(ptent)) { 742 ptent = pte_swp_clear_soft_dirty(ptent); 743 } else if (pte_file(ptent)) { 744 ptent = pte_file_clear_soft_dirty(ptent); 745 } 746 747 set_pte_at(vma->vm_mm, addr, pte, ptent); 748 #endif 749 } 750 751 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 752 unsigned long end, struct mm_walk *walk) 753 { 754 struct clear_refs_private *cp = walk->private; 755 struct vm_area_struct *vma = cp->vma; 756 pte_t *pte, ptent; 757 spinlock_t *ptl; 758 struct page *page; 759 760 split_huge_page_pmd(vma, addr, pmd); 761 if (pmd_trans_unstable(pmd)) 762 return 0; 763 764 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 765 for (; addr != end; pte++, addr += PAGE_SIZE) { 766 ptent = *pte; 767 768 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 769 clear_soft_dirty(vma, addr, pte); 770 continue; 771 } 772 773 if (!pte_present(ptent)) 774 continue; 775 776 page = vm_normal_page(vma, addr, ptent); 777 if (!page) 778 continue; 779 780 /* Clear accessed and referenced bits. */ 781 ptep_test_and_clear_young(vma, addr, pte); 782 ClearPageReferenced(page); 783 } 784 pte_unmap_unlock(pte - 1, ptl); 785 cond_resched(); 786 return 0; 787 } 788 789 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 790 size_t count, loff_t *ppos) 791 { 792 struct task_struct *task; 793 char buffer[PROC_NUMBUF]; 794 struct mm_struct *mm; 795 struct vm_area_struct *vma; 796 enum clear_refs_types type; 797 int itype; 798 int rv; 799 800 memset(buffer, 0, sizeof(buffer)); 801 if (count > sizeof(buffer) - 1) 802 count = sizeof(buffer) - 1; 803 if (copy_from_user(buffer, buf, count)) 804 return -EFAULT; 805 rv = kstrtoint(strstrip(buffer), 10, &itype); 806 if (rv < 0) 807 return rv; 808 type = (enum clear_refs_types)itype; 809 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 810 return -EINVAL; 811 812 if (type == CLEAR_REFS_SOFT_DIRTY) { 813 soft_dirty_cleared = true; 814 pr_warn_once("The pagemap bits 55-60 has changed their meaning!" 815 " See the linux/Documentation/vm/pagemap.txt for " 816 "details.\n"); 817 } 818 819 task = get_proc_task(file_inode(file)); 820 if (!task) 821 return -ESRCH; 822 mm = get_task_mm(task); 823 if (mm) { 824 struct clear_refs_private cp = { 825 .type = type, 826 }; 827 struct mm_walk clear_refs_walk = { 828 .pmd_entry = clear_refs_pte_range, 829 .mm = mm, 830 .private = &cp, 831 }; 832 down_read(&mm->mmap_sem); 833 if (type == CLEAR_REFS_SOFT_DIRTY) { 834 for (vma = mm->mmap; vma; vma = vma->vm_next) { 835 if (!(vma->vm_flags & VM_SOFTDIRTY)) 836 continue; 837 up_read(&mm->mmap_sem); 838 down_write(&mm->mmap_sem); 839 for (vma = mm->mmap; vma; vma = vma->vm_next) { 840 vma->vm_flags &= ~VM_SOFTDIRTY; 841 vma_set_page_prot(vma); 842 } 843 downgrade_write(&mm->mmap_sem); 844 break; 845 } 846 mmu_notifier_invalidate_range_start(mm, 0, -1); 847 } 848 for (vma = mm->mmap; vma; vma = vma->vm_next) { 849 cp.vma = vma; 850 if (is_vm_hugetlb_page(vma)) 851 continue; 852 /* 853 * Writing 1 to /proc/pid/clear_refs affects all pages. 854 * 855 * Writing 2 to /proc/pid/clear_refs only affects 856 * Anonymous pages. 857 * 858 * Writing 3 to /proc/pid/clear_refs only affects file 859 * mapped pages. 860 * 861 * Writing 4 to /proc/pid/clear_refs affects all pages. 862 */ 863 if (type == CLEAR_REFS_ANON && vma->vm_file) 864 continue; 865 if (type == CLEAR_REFS_MAPPED && !vma->vm_file) 866 continue; 867 walk_page_range(vma->vm_start, vma->vm_end, 868 &clear_refs_walk); 869 } 870 if (type == CLEAR_REFS_SOFT_DIRTY) 871 mmu_notifier_invalidate_range_end(mm, 0, -1); 872 flush_tlb_mm(mm); 873 up_read(&mm->mmap_sem); 874 mmput(mm); 875 } 876 put_task_struct(task); 877 878 return count; 879 } 880 881 const struct file_operations proc_clear_refs_operations = { 882 .write = clear_refs_write, 883 .llseek = noop_llseek, 884 }; 885 886 typedef struct { 887 u64 pme; 888 } pagemap_entry_t; 889 890 struct pagemapread { 891 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 892 pagemap_entry_t *buffer; 893 bool v2; 894 }; 895 896 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 897 #define PAGEMAP_WALK_MASK (PMD_MASK) 898 899 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 900 #define PM_STATUS_BITS 3 901 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) 902 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) 903 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) 904 #define PM_PSHIFT_BITS 6 905 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) 906 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) 907 #define __PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) 908 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) 909 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) 910 /* in "new" pagemap pshift bits are occupied with more status bits */ 911 #define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT)) 912 913 #define __PM_SOFT_DIRTY (1LL) 914 #define PM_PRESENT PM_STATUS(4LL) 915 #define PM_SWAP PM_STATUS(2LL) 916 #define PM_FILE PM_STATUS(1LL) 917 #define PM_NOT_PRESENT(v2) PM_STATUS2(v2, 0) 918 #define PM_END_OF_BUFFER 1 919 920 static inline pagemap_entry_t make_pme(u64 val) 921 { 922 return (pagemap_entry_t) { .pme = val }; 923 } 924 925 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 926 struct pagemapread *pm) 927 { 928 pm->buffer[pm->pos++] = *pme; 929 if (pm->pos >= pm->len) 930 return PM_END_OF_BUFFER; 931 return 0; 932 } 933 934 static int pagemap_pte_hole(unsigned long start, unsigned long end, 935 struct mm_walk *walk) 936 { 937 struct pagemapread *pm = walk->private; 938 unsigned long addr = start; 939 int err = 0; 940 941 while (addr < end) { 942 struct vm_area_struct *vma = find_vma(walk->mm, addr); 943 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2)); 944 /* End of address space hole, which we mark as non-present. */ 945 unsigned long hole_end; 946 947 if (vma) 948 hole_end = min(end, vma->vm_start); 949 else 950 hole_end = end; 951 952 for (; addr < hole_end; addr += PAGE_SIZE) { 953 err = add_to_pagemap(addr, &pme, pm); 954 if (err) 955 goto out; 956 } 957 958 if (!vma) 959 break; 960 961 /* Addresses in the VMA. */ 962 if (vma->vm_flags & VM_SOFTDIRTY) 963 pme.pme |= PM_STATUS2(pm->v2, __PM_SOFT_DIRTY); 964 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 965 err = add_to_pagemap(addr, &pme, pm); 966 if (err) 967 goto out; 968 } 969 } 970 out: 971 return err; 972 } 973 974 static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 975 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 976 { 977 u64 frame, flags; 978 struct page *page = NULL; 979 int flags2 = 0; 980 981 if (pte_present(pte)) { 982 frame = pte_pfn(pte); 983 flags = PM_PRESENT; 984 page = vm_normal_page(vma, addr, pte); 985 if (pte_soft_dirty(pte)) 986 flags2 |= __PM_SOFT_DIRTY; 987 } else if (is_swap_pte(pte)) { 988 swp_entry_t entry; 989 if (pte_swp_soft_dirty(pte)) 990 flags2 |= __PM_SOFT_DIRTY; 991 entry = pte_to_swp_entry(pte); 992 frame = swp_type(entry) | 993 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 994 flags = PM_SWAP; 995 if (is_migration_entry(entry)) 996 page = migration_entry_to_page(entry); 997 } else { 998 if (vma->vm_flags & VM_SOFTDIRTY) 999 flags2 |= __PM_SOFT_DIRTY; 1000 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2)); 1001 return; 1002 } 1003 1004 if (page && !PageAnon(page)) 1005 flags |= PM_FILE; 1006 if ((vma->vm_flags & VM_SOFTDIRTY)) 1007 flags2 |= __PM_SOFT_DIRTY; 1008 1009 *pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, flags2) | flags); 1010 } 1011 1012 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1013 static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 1014 pmd_t pmd, int offset, int pmd_flags2) 1015 { 1016 /* 1017 * Currently pmd for thp is always present because thp can not be 1018 * swapped-out, migrated, or HWPOISONed (split in such cases instead.) 1019 * This if-check is just to prepare for future implementation. 1020 */ 1021 if (pmd_present(pmd)) 1022 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset) 1023 | PM_STATUS2(pm->v2, pmd_flags2) | PM_PRESENT); 1024 else 1025 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, pmd_flags2)); 1026 } 1027 #else 1028 static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 1029 pmd_t pmd, int offset, int pmd_flags2) 1030 { 1031 } 1032 #endif 1033 1034 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 1035 struct mm_walk *walk) 1036 { 1037 struct vm_area_struct *vma; 1038 struct pagemapread *pm = walk->private; 1039 spinlock_t *ptl; 1040 pte_t *pte; 1041 int err = 0; 1042 1043 /* find the first VMA at or above 'addr' */ 1044 vma = find_vma(walk->mm, addr); 1045 if (vma && pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { 1046 int pmd_flags2; 1047 1048 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(*pmd)) 1049 pmd_flags2 = __PM_SOFT_DIRTY; 1050 else 1051 pmd_flags2 = 0; 1052 1053 for (; addr != end; addr += PAGE_SIZE) { 1054 unsigned long offset; 1055 pagemap_entry_t pme; 1056 1057 offset = (addr & ~PAGEMAP_WALK_MASK) >> 1058 PAGE_SHIFT; 1059 thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset, pmd_flags2); 1060 err = add_to_pagemap(addr, &pme, pm); 1061 if (err) 1062 break; 1063 } 1064 spin_unlock(ptl); 1065 return err; 1066 } 1067 1068 if (pmd_trans_unstable(pmd)) 1069 return 0; 1070 1071 while (1) { 1072 /* End of address space hole, which we mark as non-present. */ 1073 unsigned long hole_end; 1074 1075 if (vma) 1076 hole_end = min(end, vma->vm_start); 1077 else 1078 hole_end = end; 1079 1080 for (; addr < hole_end; addr += PAGE_SIZE) { 1081 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2)); 1082 1083 err = add_to_pagemap(addr, &pme, pm); 1084 if (err) 1085 return err; 1086 } 1087 1088 if (!vma || vma->vm_start >= end) 1089 break; 1090 /* 1091 * We can't possibly be in a hugetlb VMA. In general, 1092 * for a mm_walk with a pmd_entry and a hugetlb_entry, 1093 * the pmd_entry can only be called on addresses in a 1094 * hugetlb if the walk starts in a non-hugetlb VMA and 1095 * spans a hugepage VMA. Since pagemap_read walks are 1096 * PMD-sized and PMD-aligned, this will never be true. 1097 */ 1098 BUG_ON(is_vm_hugetlb_page(vma)); 1099 1100 /* Addresses in the VMA. */ 1101 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1102 pagemap_entry_t pme; 1103 pte = pte_offset_map(pmd, addr); 1104 pte_to_pagemap_entry(&pme, pm, vma, addr, *pte); 1105 pte_unmap(pte); 1106 err = add_to_pagemap(addr, &pme, pm); 1107 if (err) 1108 return err; 1109 } 1110 1111 if (addr == end) 1112 break; 1113 1114 vma = find_vma(walk->mm, addr); 1115 } 1116 1117 cond_resched(); 1118 1119 return err; 1120 } 1121 1122 #ifdef CONFIG_HUGETLB_PAGE 1123 static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 1124 pte_t pte, int offset, int flags2) 1125 { 1126 if (pte_present(pte)) 1127 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) | 1128 PM_STATUS2(pm->v2, flags2) | 1129 PM_PRESENT); 1130 else 1131 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | 1132 PM_STATUS2(pm->v2, flags2)); 1133 } 1134 1135 /* This function walks within one hugetlb entry in the single call */ 1136 static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask, 1137 unsigned long addr, unsigned long end, 1138 struct mm_walk *walk) 1139 { 1140 struct pagemapread *pm = walk->private; 1141 struct vm_area_struct *vma; 1142 int err = 0; 1143 int flags2; 1144 pagemap_entry_t pme; 1145 1146 vma = find_vma(walk->mm, addr); 1147 WARN_ON_ONCE(!vma); 1148 1149 if (vma && (vma->vm_flags & VM_SOFTDIRTY)) 1150 flags2 = __PM_SOFT_DIRTY; 1151 else 1152 flags2 = 0; 1153 1154 for (; addr != end; addr += PAGE_SIZE) { 1155 int offset = (addr & ~hmask) >> PAGE_SHIFT; 1156 huge_pte_to_pagemap_entry(&pme, pm, *pte, offset, flags2); 1157 err = add_to_pagemap(addr, &pme, pm); 1158 if (err) 1159 return err; 1160 } 1161 1162 cond_resched(); 1163 1164 return err; 1165 } 1166 #endif /* HUGETLB_PAGE */ 1167 1168 /* 1169 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1170 * 1171 * For each page in the address space, this file contains one 64-bit entry 1172 * consisting of the following: 1173 * 1174 * Bits 0-54 page frame number (PFN) if present 1175 * Bits 0-4 swap type if swapped 1176 * Bits 5-54 swap offset if swapped 1177 * Bits 55-60 page shift (page size = 1<<page shift) 1178 * Bit 61 page is file-page or shared-anon 1179 * Bit 62 page swapped 1180 * Bit 63 page present 1181 * 1182 * If the page is not present but in swap, then the PFN contains an 1183 * encoding of the swap file number and the page's offset into the 1184 * swap. Unmapped pages return a null PFN. This allows determining 1185 * precisely which pages are mapped (or in swap) and comparing mapped 1186 * pages between processes. 1187 * 1188 * Efficient users of this interface will use /proc/pid/maps to 1189 * determine which areas of memory are actually mapped and llseek to 1190 * skip over unmapped regions. 1191 */ 1192 static ssize_t pagemap_read(struct file *file, char __user *buf, 1193 size_t count, loff_t *ppos) 1194 { 1195 struct task_struct *task = get_proc_task(file_inode(file)); 1196 struct mm_struct *mm; 1197 struct pagemapread pm; 1198 int ret = -ESRCH; 1199 struct mm_walk pagemap_walk = {}; 1200 unsigned long src; 1201 unsigned long svpfn; 1202 unsigned long start_vaddr; 1203 unsigned long end_vaddr; 1204 int copied = 0; 1205 1206 if (!task) 1207 goto out; 1208 1209 ret = -EINVAL; 1210 /* file position must be aligned */ 1211 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1212 goto out_task; 1213 1214 ret = 0; 1215 if (!count) 1216 goto out_task; 1217 1218 pm.v2 = soft_dirty_cleared; 1219 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1220 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY); 1221 ret = -ENOMEM; 1222 if (!pm.buffer) 1223 goto out_task; 1224 1225 mm = mm_access(task, PTRACE_MODE_READ); 1226 ret = PTR_ERR(mm); 1227 if (!mm || IS_ERR(mm)) 1228 goto out_free; 1229 1230 pagemap_walk.pmd_entry = pagemap_pte_range; 1231 pagemap_walk.pte_hole = pagemap_pte_hole; 1232 #ifdef CONFIG_HUGETLB_PAGE 1233 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 1234 #endif 1235 pagemap_walk.mm = mm; 1236 pagemap_walk.private = ± 1237 1238 src = *ppos; 1239 svpfn = src / PM_ENTRY_BYTES; 1240 start_vaddr = svpfn << PAGE_SHIFT; 1241 end_vaddr = TASK_SIZE_OF(task); 1242 1243 /* watch out for wraparound */ 1244 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT) 1245 start_vaddr = end_vaddr; 1246 1247 /* 1248 * The odds are that this will stop walking way 1249 * before end_vaddr, because the length of the 1250 * user buffer is tracked in "pm", and the walk 1251 * will stop when we hit the end of the buffer. 1252 */ 1253 ret = 0; 1254 while (count && (start_vaddr < end_vaddr)) { 1255 int len; 1256 unsigned long end; 1257 1258 pm.pos = 0; 1259 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1260 /* overflow ? */ 1261 if (end < start_vaddr || end > end_vaddr) 1262 end = end_vaddr; 1263 down_read(&mm->mmap_sem); 1264 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 1265 up_read(&mm->mmap_sem); 1266 start_vaddr = end; 1267 1268 len = min(count, PM_ENTRY_BYTES * pm.pos); 1269 if (copy_to_user(buf, pm.buffer, len)) { 1270 ret = -EFAULT; 1271 goto out_mm; 1272 } 1273 copied += len; 1274 buf += len; 1275 count -= len; 1276 } 1277 *ppos += copied; 1278 if (!ret || ret == PM_END_OF_BUFFER) 1279 ret = copied; 1280 1281 out_mm: 1282 mmput(mm); 1283 out_free: 1284 kfree(pm.buffer); 1285 out_task: 1286 put_task_struct(task); 1287 out: 1288 return ret; 1289 } 1290 1291 static int pagemap_open(struct inode *inode, struct file *file) 1292 { 1293 pr_warn_once("Bits 55-60 of /proc/PID/pagemap entries are about " 1294 "to stop being page-shift some time soon. See the " 1295 "linux/Documentation/vm/pagemap.txt for details.\n"); 1296 return 0; 1297 } 1298 1299 const struct file_operations proc_pagemap_operations = { 1300 .llseek = mem_lseek, /* borrow this */ 1301 .read = pagemap_read, 1302 .open = pagemap_open, 1303 }; 1304 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1305 1306 #ifdef CONFIG_NUMA 1307 1308 struct numa_maps { 1309 struct vm_area_struct *vma; 1310 unsigned long pages; 1311 unsigned long anon; 1312 unsigned long active; 1313 unsigned long writeback; 1314 unsigned long mapcount_max; 1315 unsigned long dirty; 1316 unsigned long swapcache; 1317 unsigned long node[MAX_NUMNODES]; 1318 }; 1319 1320 struct numa_maps_private { 1321 struct proc_maps_private proc_maps; 1322 struct numa_maps md; 1323 }; 1324 1325 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1326 unsigned long nr_pages) 1327 { 1328 int count = page_mapcount(page); 1329 1330 md->pages += nr_pages; 1331 if (pte_dirty || PageDirty(page)) 1332 md->dirty += nr_pages; 1333 1334 if (PageSwapCache(page)) 1335 md->swapcache += nr_pages; 1336 1337 if (PageActive(page) || PageUnevictable(page)) 1338 md->active += nr_pages; 1339 1340 if (PageWriteback(page)) 1341 md->writeback += nr_pages; 1342 1343 if (PageAnon(page)) 1344 md->anon += nr_pages; 1345 1346 if (count > md->mapcount_max) 1347 md->mapcount_max = count; 1348 1349 md->node[page_to_nid(page)] += nr_pages; 1350 } 1351 1352 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1353 unsigned long addr) 1354 { 1355 struct page *page; 1356 int nid; 1357 1358 if (!pte_present(pte)) 1359 return NULL; 1360 1361 page = vm_normal_page(vma, addr, pte); 1362 if (!page) 1363 return NULL; 1364 1365 if (PageReserved(page)) 1366 return NULL; 1367 1368 nid = page_to_nid(page); 1369 if (!node_isset(nid, node_states[N_MEMORY])) 1370 return NULL; 1371 1372 return page; 1373 } 1374 1375 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1376 unsigned long end, struct mm_walk *walk) 1377 { 1378 struct numa_maps *md; 1379 spinlock_t *ptl; 1380 pte_t *orig_pte; 1381 pte_t *pte; 1382 1383 md = walk->private; 1384 1385 if (pmd_trans_huge_lock(pmd, md->vma, &ptl) == 1) { 1386 pte_t huge_pte = *(pte_t *)pmd; 1387 struct page *page; 1388 1389 page = can_gather_numa_stats(huge_pte, md->vma, addr); 1390 if (page) 1391 gather_stats(page, md, pte_dirty(huge_pte), 1392 HPAGE_PMD_SIZE/PAGE_SIZE); 1393 spin_unlock(ptl); 1394 return 0; 1395 } 1396 1397 if (pmd_trans_unstable(pmd)) 1398 return 0; 1399 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1400 do { 1401 struct page *page = can_gather_numa_stats(*pte, md->vma, addr); 1402 if (!page) 1403 continue; 1404 gather_stats(page, md, pte_dirty(*pte), 1); 1405 1406 } while (pte++, addr += PAGE_SIZE, addr != end); 1407 pte_unmap_unlock(orig_pte, ptl); 1408 return 0; 1409 } 1410 #ifdef CONFIG_HUGETLB_PAGE 1411 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1412 unsigned long addr, unsigned long end, struct mm_walk *walk) 1413 { 1414 struct numa_maps *md; 1415 struct page *page; 1416 1417 if (!pte_present(*pte)) 1418 return 0; 1419 1420 page = pte_page(*pte); 1421 if (!page) 1422 return 0; 1423 1424 md = walk->private; 1425 gather_stats(page, md, pte_dirty(*pte), 1); 1426 return 0; 1427 } 1428 1429 #else 1430 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1431 unsigned long addr, unsigned long end, struct mm_walk *walk) 1432 { 1433 return 0; 1434 } 1435 #endif 1436 1437 /* 1438 * Display pages allocated per node and memory policy via /proc. 1439 */ 1440 static int show_numa_map(struct seq_file *m, void *v, int is_pid) 1441 { 1442 struct numa_maps_private *numa_priv = m->private; 1443 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1444 struct vm_area_struct *vma = v; 1445 struct numa_maps *md = &numa_priv->md; 1446 struct file *file = vma->vm_file; 1447 struct mm_struct *mm = vma->vm_mm; 1448 struct mm_walk walk = {}; 1449 struct mempolicy *pol; 1450 char buffer[64]; 1451 int nid; 1452 1453 if (!mm) 1454 return 0; 1455 1456 /* Ensure we start with an empty set of numa_maps statistics. */ 1457 memset(md, 0, sizeof(*md)); 1458 1459 md->vma = vma; 1460 1461 walk.hugetlb_entry = gather_hugetbl_stats; 1462 walk.pmd_entry = gather_pte_stats; 1463 walk.private = md; 1464 walk.mm = mm; 1465 1466 pol = __get_vma_policy(vma, vma->vm_start); 1467 if (pol) { 1468 mpol_to_str(buffer, sizeof(buffer), pol); 1469 mpol_cond_put(pol); 1470 } else { 1471 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1472 } 1473 1474 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1475 1476 if (file) { 1477 seq_puts(m, " file="); 1478 seq_path(m, &file->f_path, "\n\t= "); 1479 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1480 seq_puts(m, " heap"); 1481 } else { 1482 pid_t tid = pid_of_stack(proc_priv, vma, is_pid); 1483 if (tid != 0) { 1484 /* 1485 * Thread stack in /proc/PID/task/TID/maps or 1486 * the main process stack. 1487 */ 1488 if (!is_pid || (vma->vm_start <= mm->start_stack && 1489 vma->vm_end >= mm->start_stack)) 1490 seq_puts(m, " stack"); 1491 else 1492 seq_printf(m, " stack:%d", tid); 1493 } 1494 } 1495 1496 if (is_vm_hugetlb_page(vma)) 1497 seq_puts(m, " huge"); 1498 1499 walk_page_range(vma->vm_start, vma->vm_end, &walk); 1500 1501 if (!md->pages) 1502 goto out; 1503 1504 if (md->anon) 1505 seq_printf(m, " anon=%lu", md->anon); 1506 1507 if (md->dirty) 1508 seq_printf(m, " dirty=%lu", md->dirty); 1509 1510 if (md->pages != md->anon && md->pages != md->dirty) 1511 seq_printf(m, " mapped=%lu", md->pages); 1512 1513 if (md->mapcount_max > 1) 1514 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1515 1516 if (md->swapcache) 1517 seq_printf(m, " swapcache=%lu", md->swapcache); 1518 1519 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1520 seq_printf(m, " active=%lu", md->active); 1521 1522 if (md->writeback) 1523 seq_printf(m, " writeback=%lu", md->writeback); 1524 1525 for_each_node_state(nid, N_MEMORY) 1526 if (md->node[nid]) 1527 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1528 out: 1529 seq_putc(m, '\n'); 1530 m_cache_vma(m, vma); 1531 return 0; 1532 } 1533 1534 static int show_pid_numa_map(struct seq_file *m, void *v) 1535 { 1536 return show_numa_map(m, v, 1); 1537 } 1538 1539 static int show_tid_numa_map(struct seq_file *m, void *v) 1540 { 1541 return show_numa_map(m, v, 0); 1542 } 1543 1544 static const struct seq_operations proc_pid_numa_maps_op = { 1545 .start = m_start, 1546 .next = m_next, 1547 .stop = m_stop, 1548 .show = show_pid_numa_map, 1549 }; 1550 1551 static const struct seq_operations proc_tid_numa_maps_op = { 1552 .start = m_start, 1553 .next = m_next, 1554 .stop = m_stop, 1555 .show = show_tid_numa_map, 1556 }; 1557 1558 static int numa_maps_open(struct inode *inode, struct file *file, 1559 const struct seq_operations *ops) 1560 { 1561 return proc_maps_open(inode, file, ops, 1562 sizeof(struct numa_maps_private)); 1563 } 1564 1565 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1566 { 1567 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1568 } 1569 1570 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1571 { 1572 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1573 } 1574 1575 const struct file_operations proc_pid_numa_maps_operations = { 1576 .open = pid_numa_maps_open, 1577 .read = seq_read, 1578 .llseek = seq_lseek, 1579 .release = proc_map_release, 1580 }; 1581 1582 const struct file_operations proc_tid_numa_maps_operations = { 1583 .open = tid_numa_maps_open, 1584 .read = seq_read, 1585 .llseek = seq_lseek, 1586 .release = proc_map_release, 1587 }; 1588 #endif /* CONFIG_NUMA */ 1589