1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/pagewalk.h> 3 #include <linux/mm_inline.h> 4 #include <linux/hugetlb.h> 5 #include <linux/huge_mm.h> 6 #include <linux/mount.h> 7 #include <linux/ksm.h> 8 #include <linux/seq_file.h> 9 #include <linux/highmem.h> 10 #include <linux/ptrace.h> 11 #include <linux/slab.h> 12 #include <linux/pagemap.h> 13 #include <linux/mempolicy.h> 14 #include <linux/rmap.h> 15 #include <linux/swap.h> 16 #include <linux/sched/mm.h> 17 #include <linux/swapops.h> 18 #include <linux/mmu_notifier.h> 19 #include <linux/page_idle.h> 20 #include <linux/shmem_fs.h> 21 #include <linux/uaccess.h> 22 #include <linux/pkeys.h> 23 #include <linux/minmax.h> 24 #include <linux/overflow.h> 25 26 #include <asm/elf.h> 27 #include <asm/tlb.h> 28 #include <asm/tlbflush.h> 29 #include "internal.h" 30 31 #define SEQ_PUT_DEC(str, val) \ 32 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8) 33 void task_mem(struct seq_file *m, struct mm_struct *mm) 34 { 35 unsigned long text, lib, swap, anon, file, shmem; 36 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 37 38 anon = get_mm_counter(mm, MM_ANONPAGES); 39 file = get_mm_counter(mm, MM_FILEPAGES); 40 shmem = get_mm_counter(mm, MM_SHMEMPAGES); 41 42 /* 43 * Note: to minimize their overhead, mm maintains hiwater_vm and 44 * hiwater_rss only when about to *lower* total_vm or rss. Any 45 * collector of these hiwater stats must therefore get total_vm 46 * and rss too, which will usually be the higher. Barriers? not 47 * worth the effort, such snapshots can always be inconsistent. 48 */ 49 hiwater_vm = total_vm = mm->total_vm; 50 if (hiwater_vm < mm->hiwater_vm) 51 hiwater_vm = mm->hiwater_vm; 52 hiwater_rss = total_rss = anon + file + shmem; 53 if (hiwater_rss < mm->hiwater_rss) 54 hiwater_rss = mm->hiwater_rss; 55 56 /* split executable areas between text and lib */ 57 text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK); 58 text = min(text, mm->exec_vm << PAGE_SHIFT); 59 lib = (mm->exec_vm << PAGE_SHIFT) - text; 60 61 swap = get_mm_counter(mm, MM_SWAPENTS); 62 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm); 63 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm); 64 SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm); 65 SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm)); 66 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss); 67 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss); 68 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon); 69 SEQ_PUT_DEC(" kB\nRssFile:\t", file); 70 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem); 71 SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm); 72 SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm); 73 seq_put_decimal_ull_width(m, 74 " kB\nVmExe:\t", text >> 10, 8); 75 seq_put_decimal_ull_width(m, 76 " kB\nVmLib:\t", lib >> 10, 8); 77 seq_put_decimal_ull_width(m, 78 " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8); 79 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap); 80 seq_puts(m, " kB\n"); 81 hugetlb_report_usage(m, mm); 82 } 83 #undef SEQ_PUT_DEC 84 85 unsigned long task_vsize(struct mm_struct *mm) 86 { 87 return PAGE_SIZE * mm->total_vm; 88 } 89 90 unsigned long task_statm(struct mm_struct *mm, 91 unsigned long *shared, unsigned long *text, 92 unsigned long *data, unsigned long *resident) 93 { 94 *shared = get_mm_counter(mm, MM_FILEPAGES) + 95 get_mm_counter(mm, MM_SHMEMPAGES); 96 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 97 >> PAGE_SHIFT; 98 *data = mm->data_vm + mm->stack_vm; 99 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 100 return mm->total_vm; 101 } 102 103 #ifdef CONFIG_NUMA 104 /* 105 * Save get_task_policy() for show_numa_map(). 106 */ 107 static void hold_task_mempolicy(struct proc_maps_private *priv) 108 { 109 struct task_struct *task = priv->task; 110 111 task_lock(task); 112 priv->task_mempolicy = get_task_policy(task); 113 mpol_get(priv->task_mempolicy); 114 task_unlock(task); 115 } 116 static void release_task_mempolicy(struct proc_maps_private *priv) 117 { 118 mpol_put(priv->task_mempolicy); 119 } 120 #else 121 static void hold_task_mempolicy(struct proc_maps_private *priv) 122 { 123 } 124 static void release_task_mempolicy(struct proc_maps_private *priv) 125 { 126 } 127 #endif 128 129 static struct vm_area_struct *proc_get_vma(struct proc_maps_private *priv, 130 loff_t *ppos) 131 { 132 struct vm_area_struct *vma = vma_next(&priv->iter); 133 134 if (vma) { 135 *ppos = vma->vm_start; 136 } else { 137 *ppos = -2UL; 138 vma = get_gate_vma(priv->mm); 139 } 140 141 return vma; 142 } 143 144 static void *m_start(struct seq_file *m, loff_t *ppos) 145 { 146 struct proc_maps_private *priv = m->private; 147 unsigned long last_addr = *ppos; 148 struct mm_struct *mm; 149 150 /* See m_next(). Zero at the start or after lseek. */ 151 if (last_addr == -1UL) 152 return NULL; 153 154 priv->task = get_proc_task(priv->inode); 155 if (!priv->task) 156 return ERR_PTR(-ESRCH); 157 158 mm = priv->mm; 159 if (!mm || !mmget_not_zero(mm)) { 160 put_task_struct(priv->task); 161 priv->task = NULL; 162 return NULL; 163 } 164 165 if (mmap_read_lock_killable(mm)) { 166 mmput(mm); 167 put_task_struct(priv->task); 168 priv->task = NULL; 169 return ERR_PTR(-EINTR); 170 } 171 172 vma_iter_init(&priv->iter, mm, last_addr); 173 hold_task_mempolicy(priv); 174 if (last_addr == -2UL) 175 return get_gate_vma(mm); 176 177 return proc_get_vma(priv, ppos); 178 } 179 180 static void *m_next(struct seq_file *m, void *v, loff_t *ppos) 181 { 182 if (*ppos == -2UL) { 183 *ppos = -1UL; 184 return NULL; 185 } 186 return proc_get_vma(m->private, ppos); 187 } 188 189 static void m_stop(struct seq_file *m, void *v) 190 { 191 struct proc_maps_private *priv = m->private; 192 struct mm_struct *mm = priv->mm; 193 194 if (!priv->task) 195 return; 196 197 release_task_mempolicy(priv); 198 mmap_read_unlock(mm); 199 mmput(mm); 200 put_task_struct(priv->task); 201 priv->task = NULL; 202 } 203 204 static int proc_maps_open(struct inode *inode, struct file *file, 205 const struct seq_operations *ops, int psize) 206 { 207 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 208 209 if (!priv) 210 return -ENOMEM; 211 212 priv->inode = inode; 213 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 214 if (IS_ERR(priv->mm)) { 215 int err = PTR_ERR(priv->mm); 216 217 seq_release_private(inode, file); 218 return err; 219 } 220 221 return 0; 222 } 223 224 static int proc_map_release(struct inode *inode, struct file *file) 225 { 226 struct seq_file *seq = file->private_data; 227 struct proc_maps_private *priv = seq->private; 228 229 if (priv->mm) 230 mmdrop(priv->mm); 231 232 return seq_release_private(inode, file); 233 } 234 235 static int do_maps_open(struct inode *inode, struct file *file, 236 const struct seq_operations *ops) 237 { 238 return proc_maps_open(inode, file, ops, 239 sizeof(struct proc_maps_private)); 240 } 241 242 static void show_vma_header_prefix(struct seq_file *m, 243 unsigned long start, unsigned long end, 244 vm_flags_t flags, unsigned long long pgoff, 245 dev_t dev, unsigned long ino) 246 { 247 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 248 seq_put_hex_ll(m, NULL, start, 8); 249 seq_put_hex_ll(m, "-", end, 8); 250 seq_putc(m, ' '); 251 seq_putc(m, flags & VM_READ ? 'r' : '-'); 252 seq_putc(m, flags & VM_WRITE ? 'w' : '-'); 253 seq_putc(m, flags & VM_EXEC ? 'x' : '-'); 254 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p'); 255 seq_put_hex_ll(m, " ", pgoff, 8); 256 seq_put_hex_ll(m, " ", MAJOR(dev), 2); 257 seq_put_hex_ll(m, ":", MINOR(dev), 2); 258 seq_put_decimal_ull(m, " ", ino); 259 seq_putc(m, ' '); 260 } 261 262 static void 263 show_map_vma(struct seq_file *m, struct vm_area_struct *vma) 264 { 265 struct anon_vma_name *anon_name = NULL; 266 struct mm_struct *mm = vma->vm_mm; 267 struct file *file = vma->vm_file; 268 vm_flags_t flags = vma->vm_flags; 269 unsigned long ino = 0; 270 unsigned long long pgoff = 0; 271 unsigned long start, end; 272 dev_t dev = 0; 273 const char *name = NULL; 274 275 if (file) { 276 struct inode *inode = file_inode(vma->vm_file); 277 dev = inode->i_sb->s_dev; 278 ino = inode->i_ino; 279 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 280 } 281 282 start = vma->vm_start; 283 end = vma->vm_end; 284 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 285 if (mm) 286 anon_name = anon_vma_name(vma); 287 288 /* 289 * Print the dentry name for named mappings, and a 290 * special [heap] marker for the heap: 291 */ 292 if (file) { 293 seq_pad(m, ' '); 294 /* 295 * If user named this anon shared memory via 296 * prctl(PR_SET_VMA ..., use the provided name. 297 */ 298 if (anon_name) 299 seq_printf(m, "[anon_shmem:%s]", anon_name->name); 300 else 301 seq_file_path(m, file, "\n"); 302 goto done; 303 } 304 305 if (vma->vm_ops && vma->vm_ops->name) { 306 name = vma->vm_ops->name(vma); 307 if (name) 308 goto done; 309 } 310 311 name = arch_vma_name(vma); 312 if (!name) { 313 if (!mm) { 314 name = "[vdso]"; 315 goto done; 316 } 317 318 if (vma_is_initial_heap(vma)) { 319 name = "[heap]"; 320 goto done; 321 } 322 323 if (vma_is_initial_stack(vma)) { 324 name = "[stack]"; 325 goto done; 326 } 327 328 if (anon_name) { 329 seq_pad(m, ' '); 330 seq_printf(m, "[anon:%s]", anon_name->name); 331 } 332 } 333 334 done: 335 if (name) { 336 seq_pad(m, ' '); 337 seq_puts(m, name); 338 } 339 seq_putc(m, '\n'); 340 } 341 342 static int show_map(struct seq_file *m, void *v) 343 { 344 show_map_vma(m, v); 345 return 0; 346 } 347 348 static const struct seq_operations proc_pid_maps_op = { 349 .start = m_start, 350 .next = m_next, 351 .stop = m_stop, 352 .show = show_map 353 }; 354 355 static int pid_maps_open(struct inode *inode, struct file *file) 356 { 357 return do_maps_open(inode, file, &proc_pid_maps_op); 358 } 359 360 const struct file_operations proc_pid_maps_operations = { 361 .open = pid_maps_open, 362 .read = seq_read, 363 .llseek = seq_lseek, 364 .release = proc_map_release, 365 }; 366 367 /* 368 * Proportional Set Size(PSS): my share of RSS. 369 * 370 * PSS of a process is the count of pages it has in memory, where each 371 * page is divided by the number of processes sharing it. So if a 372 * process has 1000 pages all to itself, and 1000 shared with one other 373 * process, its PSS will be 1500. 374 * 375 * To keep (accumulated) division errors low, we adopt a 64bit 376 * fixed-point pss counter to minimize division errors. So (pss >> 377 * PSS_SHIFT) would be the real byte count. 378 * 379 * A shift of 12 before division means (assuming 4K page size): 380 * - 1M 3-user-pages add up to 8KB errors; 381 * - supports mapcount up to 2^24, or 16M; 382 * - supports PSS up to 2^52 bytes, or 4PB. 383 */ 384 #define PSS_SHIFT 12 385 386 #ifdef CONFIG_PROC_PAGE_MONITOR 387 struct mem_size_stats { 388 unsigned long resident; 389 unsigned long shared_clean; 390 unsigned long shared_dirty; 391 unsigned long private_clean; 392 unsigned long private_dirty; 393 unsigned long referenced; 394 unsigned long anonymous; 395 unsigned long lazyfree; 396 unsigned long anonymous_thp; 397 unsigned long shmem_thp; 398 unsigned long file_thp; 399 unsigned long swap; 400 unsigned long shared_hugetlb; 401 unsigned long private_hugetlb; 402 unsigned long ksm; 403 u64 pss; 404 u64 pss_anon; 405 u64 pss_file; 406 u64 pss_shmem; 407 u64 pss_dirty; 408 u64 pss_locked; 409 u64 swap_pss; 410 }; 411 412 static void smaps_page_accumulate(struct mem_size_stats *mss, 413 struct page *page, unsigned long size, unsigned long pss, 414 bool dirty, bool locked, bool private) 415 { 416 mss->pss += pss; 417 418 if (PageAnon(page)) 419 mss->pss_anon += pss; 420 else if (PageSwapBacked(page)) 421 mss->pss_shmem += pss; 422 else 423 mss->pss_file += pss; 424 425 if (locked) 426 mss->pss_locked += pss; 427 428 if (dirty || PageDirty(page)) { 429 mss->pss_dirty += pss; 430 if (private) 431 mss->private_dirty += size; 432 else 433 mss->shared_dirty += size; 434 } else { 435 if (private) 436 mss->private_clean += size; 437 else 438 mss->shared_clean += size; 439 } 440 } 441 442 static void smaps_account(struct mem_size_stats *mss, struct page *page, 443 bool compound, bool young, bool dirty, bool locked, 444 bool migration) 445 { 446 int i, nr = compound ? compound_nr(page) : 1; 447 unsigned long size = nr * PAGE_SIZE; 448 449 /* 450 * First accumulate quantities that depend only on |size| and the type 451 * of the compound page. 452 */ 453 if (PageAnon(page)) { 454 mss->anonymous += size; 455 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 456 mss->lazyfree += size; 457 } 458 459 if (PageKsm(page)) 460 mss->ksm += size; 461 462 mss->resident += size; 463 /* Accumulate the size in pages that have been accessed. */ 464 if (young || page_is_young(page) || PageReferenced(page)) 465 mss->referenced += size; 466 467 /* 468 * Then accumulate quantities that may depend on sharing, or that may 469 * differ page-by-page. 470 * 471 * page_count(page) == 1 guarantees the page is mapped exactly once. 472 * If any subpage of the compound page mapped with PTE it would elevate 473 * page_count(). 474 * 475 * The page_mapcount() is called to get a snapshot of the mapcount. 476 * Without holding the page lock this snapshot can be slightly wrong as 477 * we cannot always read the mapcount atomically. It is not safe to 478 * call page_mapcount() even with PTL held if the page is not mapped, 479 * especially for migration entries. Treat regular migration entries 480 * as mapcount == 1. 481 */ 482 if ((page_count(page) == 1) || migration) { 483 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, 484 locked, true); 485 return; 486 } 487 for (i = 0; i < nr; i++, page++) { 488 int mapcount = page_mapcount(page); 489 unsigned long pss = PAGE_SIZE << PSS_SHIFT; 490 if (mapcount >= 2) 491 pss /= mapcount; 492 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked, 493 mapcount < 2); 494 } 495 } 496 497 #ifdef CONFIG_SHMEM 498 static int smaps_pte_hole(unsigned long addr, unsigned long end, 499 __always_unused int depth, struct mm_walk *walk) 500 { 501 struct mem_size_stats *mss = walk->private; 502 struct vm_area_struct *vma = walk->vma; 503 504 mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping, 505 linear_page_index(vma, addr), 506 linear_page_index(vma, end)); 507 508 return 0; 509 } 510 #else 511 #define smaps_pte_hole NULL 512 #endif /* CONFIG_SHMEM */ 513 514 static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk) 515 { 516 #ifdef CONFIG_SHMEM 517 if (walk->ops->pte_hole) { 518 /* depth is not used */ 519 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk); 520 } 521 #endif 522 } 523 524 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 525 struct mm_walk *walk) 526 { 527 struct mem_size_stats *mss = walk->private; 528 struct vm_area_struct *vma = walk->vma; 529 bool locked = !!(vma->vm_flags & VM_LOCKED); 530 struct page *page = NULL; 531 bool migration = false, young = false, dirty = false; 532 pte_t ptent = ptep_get(pte); 533 534 if (pte_present(ptent)) { 535 page = vm_normal_page(vma, addr, ptent); 536 young = pte_young(ptent); 537 dirty = pte_dirty(ptent); 538 } else if (is_swap_pte(ptent)) { 539 swp_entry_t swpent = pte_to_swp_entry(ptent); 540 541 if (!non_swap_entry(swpent)) { 542 int mapcount; 543 544 mss->swap += PAGE_SIZE; 545 mapcount = swp_swapcount(swpent); 546 if (mapcount >= 2) { 547 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 548 549 do_div(pss_delta, mapcount); 550 mss->swap_pss += pss_delta; 551 } else { 552 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 553 } 554 } else if (is_pfn_swap_entry(swpent)) { 555 if (is_migration_entry(swpent)) 556 migration = true; 557 page = pfn_swap_entry_to_page(swpent); 558 } 559 } else { 560 smaps_pte_hole_lookup(addr, walk); 561 return; 562 } 563 564 if (!page) 565 return; 566 567 smaps_account(mss, page, false, young, dirty, locked, migration); 568 } 569 570 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 571 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 572 struct mm_walk *walk) 573 { 574 struct mem_size_stats *mss = walk->private; 575 struct vm_area_struct *vma = walk->vma; 576 bool locked = !!(vma->vm_flags & VM_LOCKED); 577 struct page *page = NULL; 578 bool migration = false; 579 580 if (pmd_present(*pmd)) { 581 page = vm_normal_page_pmd(vma, addr, *pmd); 582 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { 583 swp_entry_t entry = pmd_to_swp_entry(*pmd); 584 585 if (is_migration_entry(entry)) { 586 migration = true; 587 page = pfn_swap_entry_to_page(entry); 588 } 589 } 590 if (IS_ERR_OR_NULL(page)) 591 return; 592 if (PageAnon(page)) 593 mss->anonymous_thp += HPAGE_PMD_SIZE; 594 else if (PageSwapBacked(page)) 595 mss->shmem_thp += HPAGE_PMD_SIZE; 596 else if (is_zone_device_page(page)) 597 /* pass */; 598 else 599 mss->file_thp += HPAGE_PMD_SIZE; 600 601 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), 602 locked, migration); 603 } 604 #else 605 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 606 struct mm_walk *walk) 607 { 608 } 609 #endif 610 611 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 612 struct mm_walk *walk) 613 { 614 struct vm_area_struct *vma = walk->vma; 615 pte_t *pte; 616 spinlock_t *ptl; 617 618 ptl = pmd_trans_huge_lock(pmd, vma); 619 if (ptl) { 620 smaps_pmd_entry(pmd, addr, walk); 621 spin_unlock(ptl); 622 goto out; 623 } 624 625 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 626 if (!pte) { 627 walk->action = ACTION_AGAIN; 628 return 0; 629 } 630 for (; addr != end; pte++, addr += PAGE_SIZE) 631 smaps_pte_entry(pte, addr, walk); 632 pte_unmap_unlock(pte - 1, ptl); 633 out: 634 cond_resched(); 635 return 0; 636 } 637 638 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 639 { 640 /* 641 * Don't forget to update Documentation/ on changes. 642 */ 643 static const char mnemonics[BITS_PER_LONG][2] = { 644 /* 645 * In case if we meet a flag we don't know about. 646 */ 647 [0 ... (BITS_PER_LONG-1)] = "??", 648 649 [ilog2(VM_READ)] = "rd", 650 [ilog2(VM_WRITE)] = "wr", 651 [ilog2(VM_EXEC)] = "ex", 652 [ilog2(VM_SHARED)] = "sh", 653 [ilog2(VM_MAYREAD)] = "mr", 654 [ilog2(VM_MAYWRITE)] = "mw", 655 [ilog2(VM_MAYEXEC)] = "me", 656 [ilog2(VM_MAYSHARE)] = "ms", 657 [ilog2(VM_GROWSDOWN)] = "gd", 658 [ilog2(VM_PFNMAP)] = "pf", 659 [ilog2(VM_LOCKED)] = "lo", 660 [ilog2(VM_IO)] = "io", 661 [ilog2(VM_SEQ_READ)] = "sr", 662 [ilog2(VM_RAND_READ)] = "rr", 663 [ilog2(VM_DONTCOPY)] = "dc", 664 [ilog2(VM_DONTEXPAND)] = "de", 665 [ilog2(VM_LOCKONFAULT)] = "lf", 666 [ilog2(VM_ACCOUNT)] = "ac", 667 [ilog2(VM_NORESERVE)] = "nr", 668 [ilog2(VM_HUGETLB)] = "ht", 669 [ilog2(VM_SYNC)] = "sf", 670 [ilog2(VM_ARCH_1)] = "ar", 671 [ilog2(VM_WIPEONFORK)] = "wf", 672 [ilog2(VM_DONTDUMP)] = "dd", 673 #ifdef CONFIG_ARM64_BTI 674 [ilog2(VM_ARM64_BTI)] = "bt", 675 #endif 676 #ifdef CONFIG_MEM_SOFT_DIRTY 677 [ilog2(VM_SOFTDIRTY)] = "sd", 678 #endif 679 [ilog2(VM_MIXEDMAP)] = "mm", 680 [ilog2(VM_HUGEPAGE)] = "hg", 681 [ilog2(VM_NOHUGEPAGE)] = "nh", 682 [ilog2(VM_MERGEABLE)] = "mg", 683 [ilog2(VM_UFFD_MISSING)]= "um", 684 [ilog2(VM_UFFD_WP)] = "uw", 685 #ifdef CONFIG_ARM64_MTE 686 [ilog2(VM_MTE)] = "mt", 687 [ilog2(VM_MTE_ALLOWED)] = "", 688 #endif 689 #ifdef CONFIG_ARCH_HAS_PKEYS 690 /* These come out via ProtectionKey: */ 691 [ilog2(VM_PKEY_BIT0)] = "", 692 [ilog2(VM_PKEY_BIT1)] = "", 693 [ilog2(VM_PKEY_BIT2)] = "", 694 [ilog2(VM_PKEY_BIT3)] = "", 695 #if VM_PKEY_BIT4 696 [ilog2(VM_PKEY_BIT4)] = "", 697 #endif 698 #endif /* CONFIG_ARCH_HAS_PKEYS */ 699 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR 700 [ilog2(VM_UFFD_MINOR)] = "ui", 701 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ 702 #ifdef CONFIG_X86_USER_SHADOW_STACK 703 [ilog2(VM_SHADOW_STACK)] = "ss", 704 #endif 705 }; 706 size_t i; 707 708 seq_puts(m, "VmFlags: "); 709 for (i = 0; i < BITS_PER_LONG; i++) { 710 if (!mnemonics[i][0]) 711 continue; 712 if (vma->vm_flags & (1UL << i)) { 713 seq_putc(m, mnemonics[i][0]); 714 seq_putc(m, mnemonics[i][1]); 715 seq_putc(m, ' '); 716 } 717 } 718 seq_putc(m, '\n'); 719 } 720 721 #ifdef CONFIG_HUGETLB_PAGE 722 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 723 unsigned long addr, unsigned long end, 724 struct mm_walk *walk) 725 { 726 struct mem_size_stats *mss = walk->private; 727 struct vm_area_struct *vma = walk->vma; 728 struct page *page = NULL; 729 pte_t ptent = ptep_get(pte); 730 731 if (pte_present(ptent)) { 732 page = vm_normal_page(vma, addr, ptent); 733 } else if (is_swap_pte(ptent)) { 734 swp_entry_t swpent = pte_to_swp_entry(ptent); 735 736 if (is_pfn_swap_entry(swpent)) 737 page = pfn_swap_entry_to_page(swpent); 738 } 739 if (page) { 740 if (page_mapcount(page) >= 2 || hugetlb_pmd_shared(pte)) 741 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 742 else 743 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 744 } 745 return 0; 746 } 747 #else 748 #define smaps_hugetlb_range NULL 749 #endif /* HUGETLB_PAGE */ 750 751 static const struct mm_walk_ops smaps_walk_ops = { 752 .pmd_entry = smaps_pte_range, 753 .hugetlb_entry = smaps_hugetlb_range, 754 .walk_lock = PGWALK_RDLOCK, 755 }; 756 757 static const struct mm_walk_ops smaps_shmem_walk_ops = { 758 .pmd_entry = smaps_pte_range, 759 .hugetlb_entry = smaps_hugetlb_range, 760 .pte_hole = smaps_pte_hole, 761 .walk_lock = PGWALK_RDLOCK, 762 }; 763 764 /* 765 * Gather mem stats from @vma with the indicated beginning 766 * address @start, and keep them in @mss. 767 * 768 * Use vm_start of @vma as the beginning address if @start is 0. 769 */ 770 static void smap_gather_stats(struct vm_area_struct *vma, 771 struct mem_size_stats *mss, unsigned long start) 772 { 773 const struct mm_walk_ops *ops = &smaps_walk_ops; 774 775 /* Invalid start */ 776 if (start >= vma->vm_end) 777 return; 778 779 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 780 /* 781 * For shared or readonly shmem mappings we know that all 782 * swapped out pages belong to the shmem object, and we can 783 * obtain the swap value much more efficiently. For private 784 * writable mappings, we might have COW pages that are 785 * not affected by the parent swapped out pages of the shmem 786 * object, so we have to distinguish them during the page walk. 787 * Unless we know that the shmem object (or the part mapped by 788 * our VMA) has no swapped out pages at all. 789 */ 790 unsigned long shmem_swapped = shmem_swap_usage(vma); 791 792 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 793 !(vma->vm_flags & VM_WRITE))) { 794 mss->swap += shmem_swapped; 795 } else { 796 ops = &smaps_shmem_walk_ops; 797 } 798 } 799 800 /* mmap_lock is held in m_start */ 801 if (!start) 802 walk_page_vma(vma, ops, mss); 803 else 804 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); 805 } 806 807 #define SEQ_PUT_DEC(str, val) \ 808 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 809 810 /* Show the contents common for smaps and smaps_rollup */ 811 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 812 bool rollup_mode) 813 { 814 SEQ_PUT_DEC("Rss: ", mss->resident); 815 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 816 SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT); 817 if (rollup_mode) { 818 /* 819 * These are meaningful only for smaps_rollup, otherwise two of 820 * them are zero, and the other one is the same as Pss. 821 */ 822 SEQ_PUT_DEC(" kB\nPss_Anon: ", 823 mss->pss_anon >> PSS_SHIFT); 824 SEQ_PUT_DEC(" kB\nPss_File: ", 825 mss->pss_file >> PSS_SHIFT); 826 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 827 mss->pss_shmem >> PSS_SHIFT); 828 } 829 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 830 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 831 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 832 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 833 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 834 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 835 SEQ_PUT_DEC(" kB\nKSM: ", mss->ksm); 836 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 837 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 838 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 839 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 840 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 841 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 842 mss->private_hugetlb >> 10, 7); 843 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 844 SEQ_PUT_DEC(" kB\nSwapPss: ", 845 mss->swap_pss >> PSS_SHIFT); 846 SEQ_PUT_DEC(" kB\nLocked: ", 847 mss->pss_locked >> PSS_SHIFT); 848 seq_puts(m, " kB\n"); 849 } 850 851 static int show_smap(struct seq_file *m, void *v) 852 { 853 struct vm_area_struct *vma = v; 854 struct mem_size_stats mss; 855 856 memset(&mss, 0, sizeof(mss)); 857 858 smap_gather_stats(vma, &mss, 0); 859 860 show_map_vma(m, vma); 861 862 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 863 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 864 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 865 seq_puts(m, " kB\n"); 866 867 __show_smap(m, &mss, false); 868 869 seq_printf(m, "THPeligible: %8u\n", 870 hugepage_vma_check(vma, vma->vm_flags, true, false, true)); 871 872 if (arch_pkeys_enabled()) 873 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 874 show_smap_vma_flags(m, vma); 875 876 return 0; 877 } 878 879 static int show_smaps_rollup(struct seq_file *m, void *v) 880 { 881 struct proc_maps_private *priv = m->private; 882 struct mem_size_stats mss; 883 struct mm_struct *mm = priv->mm; 884 struct vm_area_struct *vma; 885 unsigned long vma_start = 0, last_vma_end = 0; 886 int ret = 0; 887 VMA_ITERATOR(vmi, mm, 0); 888 889 priv->task = get_proc_task(priv->inode); 890 if (!priv->task) 891 return -ESRCH; 892 893 if (!mm || !mmget_not_zero(mm)) { 894 ret = -ESRCH; 895 goto out_put_task; 896 } 897 898 memset(&mss, 0, sizeof(mss)); 899 900 ret = mmap_read_lock_killable(mm); 901 if (ret) 902 goto out_put_mm; 903 904 hold_task_mempolicy(priv); 905 vma = vma_next(&vmi); 906 907 if (unlikely(!vma)) 908 goto empty_set; 909 910 vma_start = vma->vm_start; 911 do { 912 smap_gather_stats(vma, &mss, 0); 913 last_vma_end = vma->vm_end; 914 915 /* 916 * Release mmap_lock temporarily if someone wants to 917 * access it for write request. 918 */ 919 if (mmap_lock_is_contended(mm)) { 920 vma_iter_invalidate(&vmi); 921 mmap_read_unlock(mm); 922 ret = mmap_read_lock_killable(mm); 923 if (ret) { 924 release_task_mempolicy(priv); 925 goto out_put_mm; 926 } 927 928 /* 929 * After dropping the lock, there are four cases to 930 * consider. See the following example for explanation. 931 * 932 * +------+------+-----------+ 933 * | VMA1 | VMA2 | VMA3 | 934 * +------+------+-----------+ 935 * | | | | 936 * 4k 8k 16k 400k 937 * 938 * Suppose we drop the lock after reading VMA2 due to 939 * contention, then we get: 940 * 941 * last_vma_end = 16k 942 * 943 * 1) VMA2 is freed, but VMA3 exists: 944 * 945 * vma_next(vmi) will return VMA3. 946 * In this case, just continue from VMA3. 947 * 948 * 2) VMA2 still exists: 949 * 950 * vma_next(vmi) will return VMA3. 951 * In this case, just continue from VMA3. 952 * 953 * 3) No more VMAs can be found: 954 * 955 * vma_next(vmi) will return NULL. 956 * No more things to do, just break. 957 * 958 * 4) (last_vma_end - 1) is the middle of a vma (VMA'): 959 * 960 * vma_next(vmi) will return VMA' whose range 961 * contains last_vma_end. 962 * Iterate VMA' from last_vma_end. 963 */ 964 vma = vma_next(&vmi); 965 /* Case 3 above */ 966 if (!vma) 967 break; 968 969 /* Case 1 and 2 above */ 970 if (vma->vm_start >= last_vma_end) 971 continue; 972 973 /* Case 4 above */ 974 if (vma->vm_end > last_vma_end) 975 smap_gather_stats(vma, &mss, last_vma_end); 976 } 977 } for_each_vma(vmi, vma); 978 979 empty_set: 980 show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0); 981 seq_pad(m, ' '); 982 seq_puts(m, "[rollup]\n"); 983 984 __show_smap(m, &mss, true); 985 986 release_task_mempolicy(priv); 987 mmap_read_unlock(mm); 988 989 out_put_mm: 990 mmput(mm); 991 out_put_task: 992 put_task_struct(priv->task); 993 priv->task = NULL; 994 995 return ret; 996 } 997 #undef SEQ_PUT_DEC 998 999 static const struct seq_operations proc_pid_smaps_op = { 1000 .start = m_start, 1001 .next = m_next, 1002 .stop = m_stop, 1003 .show = show_smap 1004 }; 1005 1006 static int pid_smaps_open(struct inode *inode, struct file *file) 1007 { 1008 return do_maps_open(inode, file, &proc_pid_smaps_op); 1009 } 1010 1011 static int smaps_rollup_open(struct inode *inode, struct file *file) 1012 { 1013 int ret; 1014 struct proc_maps_private *priv; 1015 1016 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 1017 if (!priv) 1018 return -ENOMEM; 1019 1020 ret = single_open(file, show_smaps_rollup, priv); 1021 if (ret) 1022 goto out_free; 1023 1024 priv->inode = inode; 1025 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 1026 if (IS_ERR(priv->mm)) { 1027 ret = PTR_ERR(priv->mm); 1028 1029 single_release(inode, file); 1030 goto out_free; 1031 } 1032 1033 return 0; 1034 1035 out_free: 1036 kfree(priv); 1037 return ret; 1038 } 1039 1040 static int smaps_rollup_release(struct inode *inode, struct file *file) 1041 { 1042 struct seq_file *seq = file->private_data; 1043 struct proc_maps_private *priv = seq->private; 1044 1045 if (priv->mm) 1046 mmdrop(priv->mm); 1047 1048 kfree(priv); 1049 return single_release(inode, file); 1050 } 1051 1052 const struct file_operations proc_pid_smaps_operations = { 1053 .open = pid_smaps_open, 1054 .read = seq_read, 1055 .llseek = seq_lseek, 1056 .release = proc_map_release, 1057 }; 1058 1059 const struct file_operations proc_pid_smaps_rollup_operations = { 1060 .open = smaps_rollup_open, 1061 .read = seq_read, 1062 .llseek = seq_lseek, 1063 .release = smaps_rollup_release, 1064 }; 1065 1066 enum clear_refs_types { 1067 CLEAR_REFS_ALL = 1, 1068 CLEAR_REFS_ANON, 1069 CLEAR_REFS_MAPPED, 1070 CLEAR_REFS_SOFT_DIRTY, 1071 CLEAR_REFS_MM_HIWATER_RSS, 1072 CLEAR_REFS_LAST, 1073 }; 1074 1075 struct clear_refs_private { 1076 enum clear_refs_types type; 1077 }; 1078 1079 #ifdef CONFIG_MEM_SOFT_DIRTY 1080 1081 static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1082 { 1083 struct page *page; 1084 1085 if (!pte_write(pte)) 1086 return false; 1087 if (!is_cow_mapping(vma->vm_flags)) 1088 return false; 1089 if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))) 1090 return false; 1091 page = vm_normal_page(vma, addr, pte); 1092 if (!page) 1093 return false; 1094 return page_maybe_dma_pinned(page); 1095 } 1096 1097 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1098 unsigned long addr, pte_t *pte) 1099 { 1100 /* 1101 * The soft-dirty tracker uses #PF-s to catch writes 1102 * to pages, so write-protect the pte as well. See the 1103 * Documentation/admin-guide/mm/soft-dirty.rst for full description 1104 * of how soft-dirty works. 1105 */ 1106 pte_t ptent = ptep_get(pte); 1107 1108 if (pte_present(ptent)) { 1109 pte_t old_pte; 1110 1111 if (pte_is_pinned(vma, addr, ptent)) 1112 return; 1113 old_pte = ptep_modify_prot_start(vma, addr, pte); 1114 ptent = pte_wrprotect(old_pte); 1115 ptent = pte_clear_soft_dirty(ptent); 1116 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1117 } else if (is_swap_pte(ptent)) { 1118 ptent = pte_swp_clear_soft_dirty(ptent); 1119 set_pte_at(vma->vm_mm, addr, pte, ptent); 1120 } 1121 } 1122 #else 1123 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1124 unsigned long addr, pte_t *pte) 1125 { 1126 } 1127 #endif 1128 1129 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 1130 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1131 unsigned long addr, pmd_t *pmdp) 1132 { 1133 pmd_t old, pmd = *pmdp; 1134 1135 if (pmd_present(pmd)) { 1136 /* See comment in change_huge_pmd() */ 1137 old = pmdp_invalidate(vma, addr, pmdp); 1138 if (pmd_dirty(old)) 1139 pmd = pmd_mkdirty(pmd); 1140 if (pmd_young(old)) 1141 pmd = pmd_mkyoung(pmd); 1142 1143 pmd = pmd_wrprotect(pmd); 1144 pmd = pmd_clear_soft_dirty(pmd); 1145 1146 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1147 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1148 pmd = pmd_swp_clear_soft_dirty(pmd); 1149 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1150 } 1151 } 1152 #else 1153 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1154 unsigned long addr, pmd_t *pmdp) 1155 { 1156 } 1157 #endif 1158 1159 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1160 unsigned long end, struct mm_walk *walk) 1161 { 1162 struct clear_refs_private *cp = walk->private; 1163 struct vm_area_struct *vma = walk->vma; 1164 pte_t *pte, ptent; 1165 spinlock_t *ptl; 1166 struct page *page; 1167 1168 ptl = pmd_trans_huge_lock(pmd, vma); 1169 if (ptl) { 1170 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1171 clear_soft_dirty_pmd(vma, addr, pmd); 1172 goto out; 1173 } 1174 1175 if (!pmd_present(*pmd)) 1176 goto out; 1177 1178 page = pmd_page(*pmd); 1179 1180 /* Clear accessed and referenced bits. */ 1181 pmdp_test_and_clear_young(vma, addr, pmd); 1182 test_and_clear_page_young(page); 1183 ClearPageReferenced(page); 1184 out: 1185 spin_unlock(ptl); 1186 return 0; 1187 } 1188 1189 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1190 if (!pte) { 1191 walk->action = ACTION_AGAIN; 1192 return 0; 1193 } 1194 for (; addr != end; pte++, addr += PAGE_SIZE) { 1195 ptent = ptep_get(pte); 1196 1197 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1198 clear_soft_dirty(vma, addr, pte); 1199 continue; 1200 } 1201 1202 if (!pte_present(ptent)) 1203 continue; 1204 1205 page = vm_normal_page(vma, addr, ptent); 1206 if (!page) 1207 continue; 1208 1209 /* Clear accessed and referenced bits. */ 1210 ptep_test_and_clear_young(vma, addr, pte); 1211 test_and_clear_page_young(page); 1212 ClearPageReferenced(page); 1213 } 1214 pte_unmap_unlock(pte - 1, ptl); 1215 cond_resched(); 1216 return 0; 1217 } 1218 1219 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1220 struct mm_walk *walk) 1221 { 1222 struct clear_refs_private *cp = walk->private; 1223 struct vm_area_struct *vma = walk->vma; 1224 1225 if (vma->vm_flags & VM_PFNMAP) 1226 return 1; 1227 1228 /* 1229 * Writing 1 to /proc/pid/clear_refs affects all pages. 1230 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1231 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1232 * Writing 4 to /proc/pid/clear_refs affects all pages. 1233 */ 1234 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1235 return 1; 1236 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1237 return 1; 1238 return 0; 1239 } 1240 1241 static const struct mm_walk_ops clear_refs_walk_ops = { 1242 .pmd_entry = clear_refs_pte_range, 1243 .test_walk = clear_refs_test_walk, 1244 .walk_lock = PGWALK_WRLOCK, 1245 }; 1246 1247 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1248 size_t count, loff_t *ppos) 1249 { 1250 struct task_struct *task; 1251 char buffer[PROC_NUMBUF]; 1252 struct mm_struct *mm; 1253 struct vm_area_struct *vma; 1254 enum clear_refs_types type; 1255 int itype; 1256 int rv; 1257 1258 memset(buffer, 0, sizeof(buffer)); 1259 if (count > sizeof(buffer) - 1) 1260 count = sizeof(buffer) - 1; 1261 if (copy_from_user(buffer, buf, count)) 1262 return -EFAULT; 1263 rv = kstrtoint(strstrip(buffer), 10, &itype); 1264 if (rv < 0) 1265 return rv; 1266 type = (enum clear_refs_types)itype; 1267 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1268 return -EINVAL; 1269 1270 task = get_proc_task(file_inode(file)); 1271 if (!task) 1272 return -ESRCH; 1273 mm = get_task_mm(task); 1274 if (mm) { 1275 VMA_ITERATOR(vmi, mm, 0); 1276 struct mmu_notifier_range range; 1277 struct clear_refs_private cp = { 1278 .type = type, 1279 }; 1280 1281 if (mmap_write_lock_killable(mm)) { 1282 count = -EINTR; 1283 goto out_mm; 1284 } 1285 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1286 /* 1287 * Writing 5 to /proc/pid/clear_refs resets the peak 1288 * resident set size to this mm's current rss value. 1289 */ 1290 reset_mm_hiwater_rss(mm); 1291 goto out_unlock; 1292 } 1293 1294 if (type == CLEAR_REFS_SOFT_DIRTY) { 1295 for_each_vma(vmi, vma) { 1296 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1297 continue; 1298 vm_flags_clear(vma, VM_SOFTDIRTY); 1299 vma_set_page_prot(vma); 1300 } 1301 1302 inc_tlb_flush_pending(mm); 1303 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1304 0, mm, 0, -1UL); 1305 mmu_notifier_invalidate_range_start(&range); 1306 } 1307 walk_page_range(mm, 0, -1, &clear_refs_walk_ops, &cp); 1308 if (type == CLEAR_REFS_SOFT_DIRTY) { 1309 mmu_notifier_invalidate_range_end(&range); 1310 flush_tlb_mm(mm); 1311 dec_tlb_flush_pending(mm); 1312 } 1313 out_unlock: 1314 mmap_write_unlock(mm); 1315 out_mm: 1316 mmput(mm); 1317 } 1318 put_task_struct(task); 1319 1320 return count; 1321 } 1322 1323 const struct file_operations proc_clear_refs_operations = { 1324 .write = clear_refs_write, 1325 .llseek = noop_llseek, 1326 }; 1327 1328 typedef struct { 1329 u64 pme; 1330 } pagemap_entry_t; 1331 1332 struct pagemapread { 1333 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1334 pagemap_entry_t *buffer; 1335 bool show_pfn; 1336 }; 1337 1338 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1339 #define PAGEMAP_WALK_MASK (PMD_MASK) 1340 1341 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1342 #define PM_PFRAME_BITS 55 1343 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1344 #define PM_SOFT_DIRTY BIT_ULL(55) 1345 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1346 #define PM_UFFD_WP BIT_ULL(57) 1347 #define PM_FILE BIT_ULL(61) 1348 #define PM_SWAP BIT_ULL(62) 1349 #define PM_PRESENT BIT_ULL(63) 1350 1351 #define PM_END_OF_BUFFER 1 1352 1353 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1354 { 1355 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1356 } 1357 1358 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1359 struct pagemapread *pm) 1360 { 1361 pm->buffer[pm->pos++] = *pme; 1362 if (pm->pos >= pm->len) 1363 return PM_END_OF_BUFFER; 1364 return 0; 1365 } 1366 1367 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1368 __always_unused int depth, struct mm_walk *walk) 1369 { 1370 struct pagemapread *pm = walk->private; 1371 unsigned long addr = start; 1372 int err = 0; 1373 1374 while (addr < end) { 1375 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1376 pagemap_entry_t pme = make_pme(0, 0); 1377 /* End of address space hole, which we mark as non-present. */ 1378 unsigned long hole_end; 1379 1380 if (vma) 1381 hole_end = min(end, vma->vm_start); 1382 else 1383 hole_end = end; 1384 1385 for (; addr < hole_end; addr += PAGE_SIZE) { 1386 err = add_to_pagemap(addr, &pme, pm); 1387 if (err) 1388 goto out; 1389 } 1390 1391 if (!vma) 1392 break; 1393 1394 /* Addresses in the VMA. */ 1395 if (vma->vm_flags & VM_SOFTDIRTY) 1396 pme = make_pme(0, PM_SOFT_DIRTY); 1397 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1398 err = add_to_pagemap(addr, &pme, pm); 1399 if (err) 1400 goto out; 1401 } 1402 } 1403 out: 1404 return err; 1405 } 1406 1407 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1408 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1409 { 1410 u64 frame = 0, flags = 0; 1411 struct page *page = NULL; 1412 bool migration = false; 1413 1414 if (pte_present(pte)) { 1415 if (pm->show_pfn) 1416 frame = pte_pfn(pte); 1417 flags |= PM_PRESENT; 1418 page = vm_normal_page(vma, addr, pte); 1419 if (pte_soft_dirty(pte)) 1420 flags |= PM_SOFT_DIRTY; 1421 if (pte_uffd_wp(pte)) 1422 flags |= PM_UFFD_WP; 1423 } else if (is_swap_pte(pte)) { 1424 swp_entry_t entry; 1425 if (pte_swp_soft_dirty(pte)) 1426 flags |= PM_SOFT_DIRTY; 1427 if (pte_swp_uffd_wp(pte)) 1428 flags |= PM_UFFD_WP; 1429 entry = pte_to_swp_entry(pte); 1430 if (pm->show_pfn) { 1431 pgoff_t offset; 1432 /* 1433 * For PFN swap offsets, keeping the offset field 1434 * to be PFN only to be compatible with old smaps. 1435 */ 1436 if (is_pfn_swap_entry(entry)) 1437 offset = swp_offset_pfn(entry); 1438 else 1439 offset = swp_offset(entry); 1440 frame = swp_type(entry) | 1441 (offset << MAX_SWAPFILES_SHIFT); 1442 } 1443 flags |= PM_SWAP; 1444 migration = is_migration_entry(entry); 1445 if (is_pfn_swap_entry(entry)) 1446 page = pfn_swap_entry_to_page(entry); 1447 if (pte_marker_entry_uffd_wp(entry)) 1448 flags |= PM_UFFD_WP; 1449 } 1450 1451 if (page && !PageAnon(page)) 1452 flags |= PM_FILE; 1453 if (page && !migration && page_mapcount(page) == 1) 1454 flags |= PM_MMAP_EXCLUSIVE; 1455 if (vma->vm_flags & VM_SOFTDIRTY) 1456 flags |= PM_SOFT_DIRTY; 1457 1458 return make_pme(frame, flags); 1459 } 1460 1461 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1462 struct mm_walk *walk) 1463 { 1464 struct vm_area_struct *vma = walk->vma; 1465 struct pagemapread *pm = walk->private; 1466 spinlock_t *ptl; 1467 pte_t *pte, *orig_pte; 1468 int err = 0; 1469 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1470 bool migration = false; 1471 1472 ptl = pmd_trans_huge_lock(pmdp, vma); 1473 if (ptl) { 1474 u64 flags = 0, frame = 0; 1475 pmd_t pmd = *pmdp; 1476 struct page *page = NULL; 1477 1478 if (vma->vm_flags & VM_SOFTDIRTY) 1479 flags |= PM_SOFT_DIRTY; 1480 1481 if (pmd_present(pmd)) { 1482 page = pmd_page(pmd); 1483 1484 flags |= PM_PRESENT; 1485 if (pmd_soft_dirty(pmd)) 1486 flags |= PM_SOFT_DIRTY; 1487 if (pmd_uffd_wp(pmd)) 1488 flags |= PM_UFFD_WP; 1489 if (pm->show_pfn) 1490 frame = pmd_pfn(pmd) + 1491 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1492 } 1493 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1494 else if (is_swap_pmd(pmd)) { 1495 swp_entry_t entry = pmd_to_swp_entry(pmd); 1496 unsigned long offset; 1497 1498 if (pm->show_pfn) { 1499 if (is_pfn_swap_entry(entry)) 1500 offset = swp_offset_pfn(entry); 1501 else 1502 offset = swp_offset(entry); 1503 offset = offset + 1504 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1505 frame = swp_type(entry) | 1506 (offset << MAX_SWAPFILES_SHIFT); 1507 } 1508 flags |= PM_SWAP; 1509 if (pmd_swp_soft_dirty(pmd)) 1510 flags |= PM_SOFT_DIRTY; 1511 if (pmd_swp_uffd_wp(pmd)) 1512 flags |= PM_UFFD_WP; 1513 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1514 migration = is_migration_entry(entry); 1515 page = pfn_swap_entry_to_page(entry); 1516 } 1517 #endif 1518 1519 if (page && !migration && page_mapcount(page) == 1) 1520 flags |= PM_MMAP_EXCLUSIVE; 1521 1522 for (; addr != end; addr += PAGE_SIZE) { 1523 pagemap_entry_t pme = make_pme(frame, flags); 1524 1525 err = add_to_pagemap(addr, &pme, pm); 1526 if (err) 1527 break; 1528 if (pm->show_pfn) { 1529 if (flags & PM_PRESENT) 1530 frame++; 1531 else if (flags & PM_SWAP) 1532 frame += (1 << MAX_SWAPFILES_SHIFT); 1533 } 1534 } 1535 spin_unlock(ptl); 1536 return err; 1537 } 1538 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1539 1540 /* 1541 * We can assume that @vma always points to a valid one and @end never 1542 * goes beyond vma->vm_end. 1543 */ 1544 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1545 if (!pte) { 1546 walk->action = ACTION_AGAIN; 1547 return err; 1548 } 1549 for (; addr < end; pte++, addr += PAGE_SIZE) { 1550 pagemap_entry_t pme; 1551 1552 pme = pte_to_pagemap_entry(pm, vma, addr, ptep_get(pte)); 1553 err = add_to_pagemap(addr, &pme, pm); 1554 if (err) 1555 break; 1556 } 1557 pte_unmap_unlock(orig_pte, ptl); 1558 1559 cond_resched(); 1560 1561 return err; 1562 } 1563 1564 #ifdef CONFIG_HUGETLB_PAGE 1565 /* This function walks within one hugetlb entry in the single call */ 1566 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1567 unsigned long addr, unsigned long end, 1568 struct mm_walk *walk) 1569 { 1570 struct pagemapread *pm = walk->private; 1571 struct vm_area_struct *vma = walk->vma; 1572 u64 flags = 0, frame = 0; 1573 int err = 0; 1574 pte_t pte; 1575 1576 if (vma->vm_flags & VM_SOFTDIRTY) 1577 flags |= PM_SOFT_DIRTY; 1578 1579 pte = huge_ptep_get(ptep); 1580 if (pte_present(pte)) { 1581 struct page *page = pte_page(pte); 1582 1583 if (!PageAnon(page)) 1584 flags |= PM_FILE; 1585 1586 if (page_mapcount(page) == 1) 1587 flags |= PM_MMAP_EXCLUSIVE; 1588 1589 if (huge_pte_uffd_wp(pte)) 1590 flags |= PM_UFFD_WP; 1591 1592 flags |= PM_PRESENT; 1593 if (pm->show_pfn) 1594 frame = pte_pfn(pte) + 1595 ((addr & ~hmask) >> PAGE_SHIFT); 1596 } else if (pte_swp_uffd_wp_any(pte)) { 1597 flags |= PM_UFFD_WP; 1598 } 1599 1600 for (; addr != end; addr += PAGE_SIZE) { 1601 pagemap_entry_t pme = make_pme(frame, flags); 1602 1603 err = add_to_pagemap(addr, &pme, pm); 1604 if (err) 1605 return err; 1606 if (pm->show_pfn && (flags & PM_PRESENT)) 1607 frame++; 1608 } 1609 1610 cond_resched(); 1611 1612 return err; 1613 } 1614 #else 1615 #define pagemap_hugetlb_range NULL 1616 #endif /* HUGETLB_PAGE */ 1617 1618 static const struct mm_walk_ops pagemap_ops = { 1619 .pmd_entry = pagemap_pmd_range, 1620 .pte_hole = pagemap_pte_hole, 1621 .hugetlb_entry = pagemap_hugetlb_range, 1622 .walk_lock = PGWALK_RDLOCK, 1623 }; 1624 1625 /* 1626 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1627 * 1628 * For each page in the address space, this file contains one 64-bit entry 1629 * consisting of the following: 1630 * 1631 * Bits 0-54 page frame number (PFN) if present 1632 * Bits 0-4 swap type if swapped 1633 * Bits 5-54 swap offset if swapped 1634 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1635 * Bit 56 page exclusively mapped 1636 * Bit 57 pte is uffd-wp write-protected 1637 * Bits 58-60 zero 1638 * Bit 61 page is file-page or shared-anon 1639 * Bit 62 page swapped 1640 * Bit 63 page present 1641 * 1642 * If the page is not present but in swap, then the PFN contains an 1643 * encoding of the swap file number and the page's offset into the 1644 * swap. Unmapped pages return a null PFN. This allows determining 1645 * precisely which pages are mapped (or in swap) and comparing mapped 1646 * pages between processes. 1647 * 1648 * Efficient users of this interface will use /proc/pid/maps to 1649 * determine which areas of memory are actually mapped and llseek to 1650 * skip over unmapped regions. 1651 */ 1652 static ssize_t pagemap_read(struct file *file, char __user *buf, 1653 size_t count, loff_t *ppos) 1654 { 1655 struct mm_struct *mm = file->private_data; 1656 struct pagemapread pm; 1657 unsigned long src; 1658 unsigned long svpfn; 1659 unsigned long start_vaddr; 1660 unsigned long end_vaddr; 1661 int ret = 0, copied = 0; 1662 1663 if (!mm || !mmget_not_zero(mm)) 1664 goto out; 1665 1666 ret = -EINVAL; 1667 /* file position must be aligned */ 1668 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1669 goto out_mm; 1670 1671 ret = 0; 1672 if (!count) 1673 goto out_mm; 1674 1675 /* do not disclose physical addresses: attack vector */ 1676 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1677 1678 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1679 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1680 ret = -ENOMEM; 1681 if (!pm.buffer) 1682 goto out_mm; 1683 1684 src = *ppos; 1685 svpfn = src / PM_ENTRY_BYTES; 1686 end_vaddr = mm->task_size; 1687 1688 /* watch out for wraparound */ 1689 start_vaddr = end_vaddr; 1690 if (svpfn <= (ULONG_MAX >> PAGE_SHIFT)) { 1691 unsigned long end; 1692 1693 ret = mmap_read_lock_killable(mm); 1694 if (ret) 1695 goto out_free; 1696 start_vaddr = untagged_addr_remote(mm, svpfn << PAGE_SHIFT); 1697 mmap_read_unlock(mm); 1698 1699 end = start_vaddr + ((count / PM_ENTRY_BYTES) << PAGE_SHIFT); 1700 if (end >= start_vaddr && end < mm->task_size) 1701 end_vaddr = end; 1702 } 1703 1704 /* Ensure the address is inside the task */ 1705 if (start_vaddr > mm->task_size) 1706 start_vaddr = end_vaddr; 1707 1708 ret = 0; 1709 while (count && (start_vaddr < end_vaddr)) { 1710 int len; 1711 unsigned long end; 1712 1713 pm.pos = 0; 1714 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1715 /* overflow ? */ 1716 if (end < start_vaddr || end > end_vaddr) 1717 end = end_vaddr; 1718 ret = mmap_read_lock_killable(mm); 1719 if (ret) 1720 goto out_free; 1721 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1722 mmap_read_unlock(mm); 1723 start_vaddr = end; 1724 1725 len = min(count, PM_ENTRY_BYTES * pm.pos); 1726 if (copy_to_user(buf, pm.buffer, len)) { 1727 ret = -EFAULT; 1728 goto out_free; 1729 } 1730 copied += len; 1731 buf += len; 1732 count -= len; 1733 } 1734 *ppos += copied; 1735 if (!ret || ret == PM_END_OF_BUFFER) 1736 ret = copied; 1737 1738 out_free: 1739 kfree(pm.buffer); 1740 out_mm: 1741 mmput(mm); 1742 out: 1743 return ret; 1744 } 1745 1746 static int pagemap_open(struct inode *inode, struct file *file) 1747 { 1748 struct mm_struct *mm; 1749 1750 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1751 if (IS_ERR(mm)) 1752 return PTR_ERR(mm); 1753 file->private_data = mm; 1754 return 0; 1755 } 1756 1757 static int pagemap_release(struct inode *inode, struct file *file) 1758 { 1759 struct mm_struct *mm = file->private_data; 1760 1761 if (mm) 1762 mmdrop(mm); 1763 return 0; 1764 } 1765 1766 #define PM_SCAN_CATEGORIES (PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN | \ 1767 PAGE_IS_FILE | PAGE_IS_PRESENT | \ 1768 PAGE_IS_SWAPPED | PAGE_IS_PFNZERO | \ 1769 PAGE_IS_HUGE) 1770 #define PM_SCAN_FLAGS (PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC) 1771 1772 struct pagemap_scan_private { 1773 struct pm_scan_arg arg; 1774 unsigned long masks_of_interest, cur_vma_category; 1775 struct page_region *vec_buf; 1776 unsigned long vec_buf_len, vec_buf_index, found_pages; 1777 struct page_region __user *vec_out; 1778 }; 1779 1780 static unsigned long pagemap_page_category(struct pagemap_scan_private *p, 1781 struct vm_area_struct *vma, 1782 unsigned long addr, pte_t pte) 1783 { 1784 unsigned long categories = 0; 1785 1786 if (pte_present(pte)) { 1787 struct page *page; 1788 1789 categories |= PAGE_IS_PRESENT; 1790 if (!pte_uffd_wp(pte)) 1791 categories |= PAGE_IS_WRITTEN; 1792 1793 if (p->masks_of_interest & PAGE_IS_FILE) { 1794 page = vm_normal_page(vma, addr, pte); 1795 if (page && !PageAnon(page)) 1796 categories |= PAGE_IS_FILE; 1797 } 1798 1799 if (is_zero_pfn(pte_pfn(pte))) 1800 categories |= PAGE_IS_PFNZERO; 1801 } else if (is_swap_pte(pte)) { 1802 swp_entry_t swp; 1803 1804 categories |= PAGE_IS_SWAPPED; 1805 if (!pte_swp_uffd_wp_any(pte)) 1806 categories |= PAGE_IS_WRITTEN; 1807 1808 if (p->masks_of_interest & PAGE_IS_FILE) { 1809 swp = pte_to_swp_entry(pte); 1810 if (is_pfn_swap_entry(swp) && 1811 !PageAnon(pfn_swap_entry_to_page(swp))) 1812 categories |= PAGE_IS_FILE; 1813 } 1814 } 1815 1816 return categories; 1817 } 1818 1819 static void make_uffd_wp_pte(struct vm_area_struct *vma, 1820 unsigned long addr, pte_t *pte) 1821 { 1822 pte_t ptent = ptep_get(pte); 1823 1824 if (pte_present(ptent)) { 1825 pte_t old_pte; 1826 1827 old_pte = ptep_modify_prot_start(vma, addr, pte); 1828 ptent = pte_mkuffd_wp(ptent); 1829 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1830 } else if (is_swap_pte(ptent)) { 1831 ptent = pte_swp_mkuffd_wp(ptent); 1832 set_pte_at(vma->vm_mm, addr, pte, ptent); 1833 } else { 1834 set_pte_at(vma->vm_mm, addr, pte, 1835 make_pte_marker(PTE_MARKER_UFFD_WP)); 1836 } 1837 } 1838 1839 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1840 static unsigned long pagemap_thp_category(struct pagemap_scan_private *p, 1841 struct vm_area_struct *vma, 1842 unsigned long addr, pmd_t pmd) 1843 { 1844 unsigned long categories = PAGE_IS_HUGE; 1845 1846 if (pmd_present(pmd)) { 1847 struct page *page; 1848 1849 categories |= PAGE_IS_PRESENT; 1850 if (!pmd_uffd_wp(pmd)) 1851 categories |= PAGE_IS_WRITTEN; 1852 1853 if (p->masks_of_interest & PAGE_IS_FILE) { 1854 page = vm_normal_page_pmd(vma, addr, pmd); 1855 if (page && !PageAnon(page)) 1856 categories |= PAGE_IS_FILE; 1857 } 1858 1859 if (is_zero_pfn(pmd_pfn(pmd))) 1860 categories |= PAGE_IS_PFNZERO; 1861 } else if (is_swap_pmd(pmd)) { 1862 swp_entry_t swp; 1863 1864 categories |= PAGE_IS_SWAPPED; 1865 if (!pmd_swp_uffd_wp(pmd)) 1866 categories |= PAGE_IS_WRITTEN; 1867 1868 if (p->masks_of_interest & PAGE_IS_FILE) { 1869 swp = pmd_to_swp_entry(pmd); 1870 if (is_pfn_swap_entry(swp) && 1871 !PageAnon(pfn_swap_entry_to_page(swp))) 1872 categories |= PAGE_IS_FILE; 1873 } 1874 } 1875 1876 return categories; 1877 } 1878 1879 static void make_uffd_wp_pmd(struct vm_area_struct *vma, 1880 unsigned long addr, pmd_t *pmdp) 1881 { 1882 pmd_t old, pmd = *pmdp; 1883 1884 if (pmd_present(pmd)) { 1885 old = pmdp_invalidate_ad(vma, addr, pmdp); 1886 pmd = pmd_mkuffd_wp(old); 1887 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1888 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1889 pmd = pmd_swp_mkuffd_wp(pmd); 1890 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1891 } 1892 } 1893 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1894 1895 #ifdef CONFIG_HUGETLB_PAGE 1896 static unsigned long pagemap_hugetlb_category(pte_t pte) 1897 { 1898 unsigned long categories = PAGE_IS_HUGE; 1899 1900 /* 1901 * According to pagemap_hugetlb_range(), file-backed HugeTLB 1902 * page cannot be swapped. So PAGE_IS_FILE is not checked for 1903 * swapped pages. 1904 */ 1905 if (pte_present(pte)) { 1906 categories |= PAGE_IS_PRESENT; 1907 if (!huge_pte_uffd_wp(pte)) 1908 categories |= PAGE_IS_WRITTEN; 1909 if (!PageAnon(pte_page(pte))) 1910 categories |= PAGE_IS_FILE; 1911 if (is_zero_pfn(pte_pfn(pte))) 1912 categories |= PAGE_IS_PFNZERO; 1913 } else if (is_swap_pte(pte)) { 1914 categories |= PAGE_IS_SWAPPED; 1915 if (!pte_swp_uffd_wp_any(pte)) 1916 categories |= PAGE_IS_WRITTEN; 1917 } 1918 1919 return categories; 1920 } 1921 1922 static void make_uffd_wp_huge_pte(struct vm_area_struct *vma, 1923 unsigned long addr, pte_t *ptep, 1924 pte_t ptent) 1925 { 1926 unsigned long psize; 1927 1928 if (is_hugetlb_entry_hwpoisoned(ptent) || is_pte_marker(ptent)) 1929 return; 1930 1931 psize = huge_page_size(hstate_vma(vma)); 1932 1933 if (is_hugetlb_entry_migration(ptent)) 1934 set_huge_pte_at(vma->vm_mm, addr, ptep, 1935 pte_swp_mkuffd_wp(ptent), psize); 1936 else if (!huge_pte_none(ptent)) 1937 huge_ptep_modify_prot_commit(vma, addr, ptep, ptent, 1938 huge_pte_mkuffd_wp(ptent)); 1939 else 1940 set_huge_pte_at(vma->vm_mm, addr, ptep, 1941 make_pte_marker(PTE_MARKER_UFFD_WP), psize); 1942 } 1943 #endif /* CONFIG_HUGETLB_PAGE */ 1944 1945 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE) 1946 static void pagemap_scan_backout_range(struct pagemap_scan_private *p, 1947 unsigned long addr, unsigned long end) 1948 { 1949 struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index]; 1950 1951 if (cur_buf->start != addr) 1952 cur_buf->end = addr; 1953 else 1954 cur_buf->start = cur_buf->end = 0; 1955 1956 p->found_pages -= (end - addr) / PAGE_SIZE; 1957 } 1958 #endif 1959 1960 static bool pagemap_scan_is_interesting_page(unsigned long categories, 1961 const struct pagemap_scan_private *p) 1962 { 1963 categories ^= p->arg.category_inverted; 1964 if ((categories & p->arg.category_mask) != p->arg.category_mask) 1965 return false; 1966 if (p->arg.category_anyof_mask && !(categories & p->arg.category_anyof_mask)) 1967 return false; 1968 1969 return true; 1970 } 1971 1972 static bool pagemap_scan_is_interesting_vma(unsigned long categories, 1973 const struct pagemap_scan_private *p) 1974 { 1975 unsigned long required = p->arg.category_mask & PAGE_IS_WPALLOWED; 1976 1977 categories ^= p->arg.category_inverted; 1978 if ((categories & required) != required) 1979 return false; 1980 1981 return true; 1982 } 1983 1984 static int pagemap_scan_test_walk(unsigned long start, unsigned long end, 1985 struct mm_walk *walk) 1986 { 1987 struct pagemap_scan_private *p = walk->private; 1988 struct vm_area_struct *vma = walk->vma; 1989 unsigned long vma_category = 0; 1990 1991 if (userfaultfd_wp_async(vma) && userfaultfd_wp_use_markers(vma)) 1992 vma_category |= PAGE_IS_WPALLOWED; 1993 else if (p->arg.flags & PM_SCAN_CHECK_WPASYNC) 1994 return -EPERM; 1995 1996 if (vma->vm_flags & VM_PFNMAP) 1997 return 1; 1998 1999 if (!pagemap_scan_is_interesting_vma(vma_category, p)) 2000 return 1; 2001 2002 p->cur_vma_category = vma_category; 2003 2004 return 0; 2005 } 2006 2007 static bool pagemap_scan_push_range(unsigned long categories, 2008 struct pagemap_scan_private *p, 2009 unsigned long addr, unsigned long end) 2010 { 2011 struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index]; 2012 2013 /* 2014 * When there is no output buffer provided at all, the sentinel values 2015 * won't match here. There is no other way for `cur_buf->end` to be 2016 * non-zero other than it being non-empty. 2017 */ 2018 if (addr == cur_buf->end && categories == cur_buf->categories) { 2019 cur_buf->end = end; 2020 return true; 2021 } 2022 2023 if (cur_buf->end) { 2024 if (p->vec_buf_index >= p->vec_buf_len - 1) 2025 return false; 2026 2027 cur_buf = &p->vec_buf[++p->vec_buf_index]; 2028 } 2029 2030 cur_buf->start = addr; 2031 cur_buf->end = end; 2032 cur_buf->categories = categories; 2033 2034 return true; 2035 } 2036 2037 static int pagemap_scan_output(unsigned long categories, 2038 struct pagemap_scan_private *p, 2039 unsigned long addr, unsigned long *end) 2040 { 2041 unsigned long n_pages, total_pages; 2042 int ret = 0; 2043 2044 if (!p->vec_buf) 2045 return 0; 2046 2047 categories &= p->arg.return_mask; 2048 2049 n_pages = (*end - addr) / PAGE_SIZE; 2050 if (check_add_overflow(p->found_pages, n_pages, &total_pages) || 2051 total_pages > p->arg.max_pages) { 2052 size_t n_too_much = total_pages - p->arg.max_pages; 2053 *end -= n_too_much * PAGE_SIZE; 2054 n_pages -= n_too_much; 2055 ret = -ENOSPC; 2056 } 2057 2058 if (!pagemap_scan_push_range(categories, p, addr, *end)) { 2059 *end = addr; 2060 n_pages = 0; 2061 ret = -ENOSPC; 2062 } 2063 2064 p->found_pages += n_pages; 2065 if (ret) 2066 p->arg.walk_end = *end; 2067 2068 return ret; 2069 } 2070 2071 static int pagemap_scan_thp_entry(pmd_t *pmd, unsigned long start, 2072 unsigned long end, struct mm_walk *walk) 2073 { 2074 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 2075 struct pagemap_scan_private *p = walk->private; 2076 struct vm_area_struct *vma = walk->vma; 2077 unsigned long categories; 2078 spinlock_t *ptl; 2079 int ret = 0; 2080 2081 ptl = pmd_trans_huge_lock(pmd, vma); 2082 if (!ptl) 2083 return -ENOENT; 2084 2085 categories = p->cur_vma_category | 2086 pagemap_thp_category(p, vma, start, *pmd); 2087 2088 if (!pagemap_scan_is_interesting_page(categories, p)) 2089 goto out_unlock; 2090 2091 ret = pagemap_scan_output(categories, p, start, &end); 2092 if (start == end) 2093 goto out_unlock; 2094 2095 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2096 goto out_unlock; 2097 if (~categories & PAGE_IS_WRITTEN) 2098 goto out_unlock; 2099 2100 /* 2101 * Break huge page into small pages if the WP operation 2102 * needs to be performed on a portion of the huge page. 2103 */ 2104 if (end != start + HPAGE_SIZE) { 2105 spin_unlock(ptl); 2106 split_huge_pmd(vma, pmd, start); 2107 pagemap_scan_backout_range(p, start, end); 2108 /* Report as if there was no THP */ 2109 return -ENOENT; 2110 } 2111 2112 make_uffd_wp_pmd(vma, start, pmd); 2113 flush_tlb_range(vma, start, end); 2114 out_unlock: 2115 spin_unlock(ptl); 2116 return ret; 2117 #else /* !CONFIG_TRANSPARENT_HUGEPAGE */ 2118 return -ENOENT; 2119 #endif 2120 } 2121 2122 static int pagemap_scan_pmd_entry(pmd_t *pmd, unsigned long start, 2123 unsigned long end, struct mm_walk *walk) 2124 { 2125 struct pagemap_scan_private *p = walk->private; 2126 struct vm_area_struct *vma = walk->vma; 2127 unsigned long addr, flush_end = 0; 2128 pte_t *pte, *start_pte; 2129 spinlock_t *ptl; 2130 int ret; 2131 2132 arch_enter_lazy_mmu_mode(); 2133 2134 ret = pagemap_scan_thp_entry(pmd, start, end, walk); 2135 if (ret != -ENOENT) { 2136 arch_leave_lazy_mmu_mode(); 2137 return ret; 2138 } 2139 2140 ret = 0; 2141 start_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, start, &ptl); 2142 if (!pte) { 2143 arch_leave_lazy_mmu_mode(); 2144 walk->action = ACTION_AGAIN; 2145 return 0; 2146 } 2147 2148 if (!p->vec_out) { 2149 /* Fast path for performing exclusive WP */ 2150 for (addr = start; addr != end; pte++, addr += PAGE_SIZE) { 2151 if (pte_uffd_wp(ptep_get(pte))) 2152 continue; 2153 make_uffd_wp_pte(vma, addr, pte); 2154 if (!flush_end) 2155 start = addr; 2156 flush_end = addr + PAGE_SIZE; 2157 } 2158 goto flush_and_return; 2159 } 2160 2161 if (!p->arg.category_anyof_mask && !p->arg.category_inverted && 2162 p->arg.category_mask == PAGE_IS_WRITTEN && 2163 p->arg.return_mask == PAGE_IS_WRITTEN) { 2164 for (addr = start; addr < end; pte++, addr += PAGE_SIZE) { 2165 unsigned long next = addr + PAGE_SIZE; 2166 2167 if (pte_uffd_wp(ptep_get(pte))) 2168 continue; 2169 ret = pagemap_scan_output(p->cur_vma_category | PAGE_IS_WRITTEN, 2170 p, addr, &next); 2171 if (next == addr) 2172 break; 2173 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2174 continue; 2175 make_uffd_wp_pte(vma, addr, pte); 2176 if (!flush_end) 2177 start = addr; 2178 flush_end = next; 2179 } 2180 goto flush_and_return; 2181 } 2182 2183 for (addr = start; addr != end; pte++, addr += PAGE_SIZE) { 2184 unsigned long categories = p->cur_vma_category | 2185 pagemap_page_category(p, vma, addr, ptep_get(pte)); 2186 unsigned long next = addr + PAGE_SIZE; 2187 2188 if (!pagemap_scan_is_interesting_page(categories, p)) 2189 continue; 2190 2191 ret = pagemap_scan_output(categories, p, addr, &next); 2192 if (next == addr) 2193 break; 2194 2195 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2196 continue; 2197 if (~categories & PAGE_IS_WRITTEN) 2198 continue; 2199 2200 make_uffd_wp_pte(vma, addr, pte); 2201 if (!flush_end) 2202 start = addr; 2203 flush_end = next; 2204 } 2205 2206 flush_and_return: 2207 if (flush_end) 2208 flush_tlb_range(vma, start, addr); 2209 2210 pte_unmap_unlock(start_pte, ptl); 2211 arch_leave_lazy_mmu_mode(); 2212 2213 cond_resched(); 2214 return ret; 2215 } 2216 2217 #ifdef CONFIG_HUGETLB_PAGE 2218 static int pagemap_scan_hugetlb_entry(pte_t *ptep, unsigned long hmask, 2219 unsigned long start, unsigned long end, 2220 struct mm_walk *walk) 2221 { 2222 struct pagemap_scan_private *p = walk->private; 2223 struct vm_area_struct *vma = walk->vma; 2224 unsigned long categories; 2225 spinlock_t *ptl; 2226 int ret = 0; 2227 pte_t pte; 2228 2229 if (~p->arg.flags & PM_SCAN_WP_MATCHING) { 2230 /* Go the short route when not write-protecting pages. */ 2231 2232 pte = huge_ptep_get(ptep); 2233 categories = p->cur_vma_category | pagemap_hugetlb_category(pte); 2234 2235 if (!pagemap_scan_is_interesting_page(categories, p)) 2236 return 0; 2237 2238 return pagemap_scan_output(categories, p, start, &end); 2239 } 2240 2241 i_mmap_lock_write(vma->vm_file->f_mapping); 2242 ptl = huge_pte_lock(hstate_vma(vma), vma->vm_mm, ptep); 2243 2244 pte = huge_ptep_get(ptep); 2245 categories = p->cur_vma_category | pagemap_hugetlb_category(pte); 2246 2247 if (!pagemap_scan_is_interesting_page(categories, p)) 2248 goto out_unlock; 2249 2250 ret = pagemap_scan_output(categories, p, start, &end); 2251 if (start == end) 2252 goto out_unlock; 2253 2254 if (~categories & PAGE_IS_WRITTEN) 2255 goto out_unlock; 2256 2257 if (end != start + HPAGE_SIZE) { 2258 /* Partial HugeTLB page WP isn't possible. */ 2259 pagemap_scan_backout_range(p, start, end); 2260 p->arg.walk_end = start; 2261 ret = 0; 2262 goto out_unlock; 2263 } 2264 2265 make_uffd_wp_huge_pte(vma, start, ptep, pte); 2266 flush_hugetlb_tlb_range(vma, start, end); 2267 2268 out_unlock: 2269 spin_unlock(ptl); 2270 i_mmap_unlock_write(vma->vm_file->f_mapping); 2271 2272 return ret; 2273 } 2274 #else 2275 #define pagemap_scan_hugetlb_entry NULL 2276 #endif 2277 2278 static int pagemap_scan_pte_hole(unsigned long addr, unsigned long end, 2279 int depth, struct mm_walk *walk) 2280 { 2281 struct pagemap_scan_private *p = walk->private; 2282 struct vm_area_struct *vma = walk->vma; 2283 int ret, err; 2284 2285 if (!vma || !pagemap_scan_is_interesting_page(p->cur_vma_category, p)) 2286 return 0; 2287 2288 ret = pagemap_scan_output(p->cur_vma_category, p, addr, &end); 2289 if (addr == end) 2290 return ret; 2291 2292 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2293 return ret; 2294 2295 err = uffd_wp_range(vma, addr, end - addr, true); 2296 if (err < 0) 2297 ret = err; 2298 2299 return ret; 2300 } 2301 2302 static const struct mm_walk_ops pagemap_scan_ops = { 2303 .test_walk = pagemap_scan_test_walk, 2304 .pmd_entry = pagemap_scan_pmd_entry, 2305 .pte_hole = pagemap_scan_pte_hole, 2306 .hugetlb_entry = pagemap_scan_hugetlb_entry, 2307 }; 2308 2309 static int pagemap_scan_get_args(struct pm_scan_arg *arg, 2310 unsigned long uarg) 2311 { 2312 if (copy_from_user(arg, (void __user *)uarg, sizeof(*arg))) 2313 return -EFAULT; 2314 2315 if (arg->size != sizeof(struct pm_scan_arg)) 2316 return -EINVAL; 2317 2318 /* Validate requested features */ 2319 if (arg->flags & ~PM_SCAN_FLAGS) 2320 return -EINVAL; 2321 if ((arg->category_inverted | arg->category_mask | 2322 arg->category_anyof_mask | arg->return_mask) & ~PM_SCAN_CATEGORIES) 2323 return -EINVAL; 2324 2325 arg->start = untagged_addr((unsigned long)arg->start); 2326 arg->end = untagged_addr((unsigned long)arg->end); 2327 arg->vec = untagged_addr((unsigned long)arg->vec); 2328 2329 /* Validate memory pointers */ 2330 if (!IS_ALIGNED(arg->start, PAGE_SIZE)) 2331 return -EINVAL; 2332 if (!access_ok((void __user *)(long)arg->start, arg->end - arg->start)) 2333 return -EFAULT; 2334 if (!arg->vec && arg->vec_len) 2335 return -EINVAL; 2336 if (arg->vec && !access_ok((void __user *)(long)arg->vec, 2337 arg->vec_len * sizeof(struct page_region))) 2338 return -EFAULT; 2339 2340 /* Fixup default values */ 2341 arg->end = ALIGN(arg->end, PAGE_SIZE); 2342 arg->walk_end = 0; 2343 if (!arg->max_pages) 2344 arg->max_pages = ULONG_MAX; 2345 2346 return 0; 2347 } 2348 2349 static int pagemap_scan_writeback_args(struct pm_scan_arg *arg, 2350 unsigned long uargl) 2351 { 2352 struct pm_scan_arg __user *uarg = (void __user *)uargl; 2353 2354 if (copy_to_user(&uarg->walk_end, &arg->walk_end, sizeof(arg->walk_end))) 2355 return -EFAULT; 2356 2357 return 0; 2358 } 2359 2360 static int pagemap_scan_init_bounce_buffer(struct pagemap_scan_private *p) 2361 { 2362 if (!p->arg.vec_len) 2363 return 0; 2364 2365 p->vec_buf_len = min_t(size_t, PAGEMAP_WALK_SIZE >> PAGE_SHIFT, 2366 p->arg.vec_len); 2367 p->vec_buf = kmalloc_array(p->vec_buf_len, sizeof(*p->vec_buf), 2368 GFP_KERNEL); 2369 if (!p->vec_buf) 2370 return -ENOMEM; 2371 2372 p->vec_buf->start = p->vec_buf->end = 0; 2373 p->vec_out = (struct page_region __user *)(long)p->arg.vec; 2374 2375 return 0; 2376 } 2377 2378 static long pagemap_scan_flush_buffer(struct pagemap_scan_private *p) 2379 { 2380 const struct page_region *buf = p->vec_buf; 2381 long n = p->vec_buf_index; 2382 2383 if (!p->vec_buf) 2384 return 0; 2385 2386 if (buf[n].end != buf[n].start) 2387 n++; 2388 2389 if (!n) 2390 return 0; 2391 2392 if (copy_to_user(p->vec_out, buf, n * sizeof(*buf))) 2393 return -EFAULT; 2394 2395 p->arg.vec_len -= n; 2396 p->vec_out += n; 2397 2398 p->vec_buf_index = 0; 2399 p->vec_buf_len = min_t(size_t, p->vec_buf_len, p->arg.vec_len); 2400 p->vec_buf->start = p->vec_buf->end = 0; 2401 2402 return n; 2403 } 2404 2405 static long do_pagemap_scan(struct mm_struct *mm, unsigned long uarg) 2406 { 2407 struct mmu_notifier_range range; 2408 struct pagemap_scan_private p = {0}; 2409 unsigned long walk_start; 2410 size_t n_ranges_out = 0; 2411 int ret; 2412 2413 ret = pagemap_scan_get_args(&p.arg, uarg); 2414 if (ret) 2415 return ret; 2416 2417 p.masks_of_interest = p.arg.category_mask | p.arg.category_anyof_mask | 2418 p.arg.return_mask; 2419 ret = pagemap_scan_init_bounce_buffer(&p); 2420 if (ret) 2421 return ret; 2422 2423 /* Protection change for the range is going to happen. */ 2424 if (p.arg.flags & PM_SCAN_WP_MATCHING) { 2425 mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, 0, 2426 mm, p.arg.start, p.arg.end); 2427 mmu_notifier_invalidate_range_start(&range); 2428 } 2429 2430 for (walk_start = p.arg.start; walk_start < p.arg.end; 2431 walk_start = p.arg.walk_end) { 2432 long n_out; 2433 2434 if (fatal_signal_pending(current)) { 2435 ret = -EINTR; 2436 break; 2437 } 2438 2439 ret = mmap_read_lock_killable(mm); 2440 if (ret) 2441 break; 2442 ret = walk_page_range(mm, walk_start, p.arg.end, 2443 &pagemap_scan_ops, &p); 2444 mmap_read_unlock(mm); 2445 2446 n_out = pagemap_scan_flush_buffer(&p); 2447 if (n_out < 0) 2448 ret = n_out; 2449 else 2450 n_ranges_out += n_out; 2451 2452 if (ret != -ENOSPC) 2453 break; 2454 2455 if (p.arg.vec_len == 0 || p.found_pages == p.arg.max_pages) 2456 break; 2457 } 2458 2459 /* ENOSPC signifies early stop (buffer full) from the walk. */ 2460 if (!ret || ret == -ENOSPC) 2461 ret = n_ranges_out; 2462 2463 /* The walk_end isn't set when ret is zero */ 2464 if (!p.arg.walk_end) 2465 p.arg.walk_end = p.arg.end; 2466 if (pagemap_scan_writeback_args(&p.arg, uarg)) 2467 ret = -EFAULT; 2468 2469 if (p.arg.flags & PM_SCAN_WP_MATCHING) 2470 mmu_notifier_invalidate_range_end(&range); 2471 2472 kfree(p.vec_buf); 2473 return ret; 2474 } 2475 2476 static long do_pagemap_cmd(struct file *file, unsigned int cmd, 2477 unsigned long arg) 2478 { 2479 struct mm_struct *mm = file->private_data; 2480 2481 switch (cmd) { 2482 case PAGEMAP_SCAN: 2483 return do_pagemap_scan(mm, arg); 2484 2485 default: 2486 return -EINVAL; 2487 } 2488 } 2489 2490 const struct file_operations proc_pagemap_operations = { 2491 .llseek = mem_lseek, /* borrow this */ 2492 .read = pagemap_read, 2493 .open = pagemap_open, 2494 .release = pagemap_release, 2495 .unlocked_ioctl = do_pagemap_cmd, 2496 .compat_ioctl = do_pagemap_cmd, 2497 }; 2498 #endif /* CONFIG_PROC_PAGE_MONITOR */ 2499 2500 #ifdef CONFIG_NUMA 2501 2502 struct numa_maps { 2503 unsigned long pages; 2504 unsigned long anon; 2505 unsigned long active; 2506 unsigned long writeback; 2507 unsigned long mapcount_max; 2508 unsigned long dirty; 2509 unsigned long swapcache; 2510 unsigned long node[MAX_NUMNODES]; 2511 }; 2512 2513 struct numa_maps_private { 2514 struct proc_maps_private proc_maps; 2515 struct numa_maps md; 2516 }; 2517 2518 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 2519 unsigned long nr_pages) 2520 { 2521 int count = page_mapcount(page); 2522 2523 md->pages += nr_pages; 2524 if (pte_dirty || PageDirty(page)) 2525 md->dirty += nr_pages; 2526 2527 if (PageSwapCache(page)) 2528 md->swapcache += nr_pages; 2529 2530 if (PageActive(page) || PageUnevictable(page)) 2531 md->active += nr_pages; 2532 2533 if (PageWriteback(page)) 2534 md->writeback += nr_pages; 2535 2536 if (PageAnon(page)) 2537 md->anon += nr_pages; 2538 2539 if (count > md->mapcount_max) 2540 md->mapcount_max = count; 2541 2542 md->node[page_to_nid(page)] += nr_pages; 2543 } 2544 2545 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 2546 unsigned long addr) 2547 { 2548 struct page *page; 2549 int nid; 2550 2551 if (!pte_present(pte)) 2552 return NULL; 2553 2554 page = vm_normal_page(vma, addr, pte); 2555 if (!page || is_zone_device_page(page)) 2556 return NULL; 2557 2558 if (PageReserved(page)) 2559 return NULL; 2560 2561 nid = page_to_nid(page); 2562 if (!node_isset(nid, node_states[N_MEMORY])) 2563 return NULL; 2564 2565 return page; 2566 } 2567 2568 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 2569 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 2570 struct vm_area_struct *vma, 2571 unsigned long addr) 2572 { 2573 struct page *page; 2574 int nid; 2575 2576 if (!pmd_present(pmd)) 2577 return NULL; 2578 2579 page = vm_normal_page_pmd(vma, addr, pmd); 2580 if (!page) 2581 return NULL; 2582 2583 if (PageReserved(page)) 2584 return NULL; 2585 2586 nid = page_to_nid(page); 2587 if (!node_isset(nid, node_states[N_MEMORY])) 2588 return NULL; 2589 2590 return page; 2591 } 2592 #endif 2593 2594 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 2595 unsigned long end, struct mm_walk *walk) 2596 { 2597 struct numa_maps *md = walk->private; 2598 struct vm_area_struct *vma = walk->vma; 2599 spinlock_t *ptl; 2600 pte_t *orig_pte; 2601 pte_t *pte; 2602 2603 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 2604 ptl = pmd_trans_huge_lock(pmd, vma); 2605 if (ptl) { 2606 struct page *page; 2607 2608 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 2609 if (page) 2610 gather_stats(page, md, pmd_dirty(*pmd), 2611 HPAGE_PMD_SIZE/PAGE_SIZE); 2612 spin_unlock(ptl); 2613 return 0; 2614 } 2615 #endif 2616 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 2617 if (!pte) { 2618 walk->action = ACTION_AGAIN; 2619 return 0; 2620 } 2621 do { 2622 pte_t ptent = ptep_get(pte); 2623 struct page *page = can_gather_numa_stats(ptent, vma, addr); 2624 if (!page) 2625 continue; 2626 gather_stats(page, md, pte_dirty(ptent), 1); 2627 2628 } while (pte++, addr += PAGE_SIZE, addr != end); 2629 pte_unmap_unlock(orig_pte, ptl); 2630 cond_resched(); 2631 return 0; 2632 } 2633 #ifdef CONFIG_HUGETLB_PAGE 2634 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 2635 unsigned long addr, unsigned long end, struct mm_walk *walk) 2636 { 2637 pte_t huge_pte = huge_ptep_get(pte); 2638 struct numa_maps *md; 2639 struct page *page; 2640 2641 if (!pte_present(huge_pte)) 2642 return 0; 2643 2644 page = pte_page(huge_pte); 2645 2646 md = walk->private; 2647 gather_stats(page, md, pte_dirty(huge_pte), 1); 2648 return 0; 2649 } 2650 2651 #else 2652 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 2653 unsigned long addr, unsigned long end, struct mm_walk *walk) 2654 { 2655 return 0; 2656 } 2657 #endif 2658 2659 static const struct mm_walk_ops show_numa_ops = { 2660 .hugetlb_entry = gather_hugetlb_stats, 2661 .pmd_entry = gather_pte_stats, 2662 .walk_lock = PGWALK_RDLOCK, 2663 }; 2664 2665 /* 2666 * Display pages allocated per node and memory policy via /proc. 2667 */ 2668 static int show_numa_map(struct seq_file *m, void *v) 2669 { 2670 struct numa_maps_private *numa_priv = m->private; 2671 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 2672 struct vm_area_struct *vma = v; 2673 struct numa_maps *md = &numa_priv->md; 2674 struct file *file = vma->vm_file; 2675 struct mm_struct *mm = vma->vm_mm; 2676 struct mempolicy *pol; 2677 char buffer[64]; 2678 int nid; 2679 2680 if (!mm) 2681 return 0; 2682 2683 /* Ensure we start with an empty set of numa_maps statistics. */ 2684 memset(md, 0, sizeof(*md)); 2685 2686 pol = __get_vma_policy(vma, vma->vm_start); 2687 if (pol) { 2688 mpol_to_str(buffer, sizeof(buffer), pol); 2689 mpol_cond_put(pol); 2690 } else { 2691 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 2692 } 2693 2694 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 2695 2696 if (file) { 2697 seq_puts(m, " file="); 2698 seq_file_path(m, file, "\n\t= "); 2699 } else if (vma_is_initial_heap(vma)) { 2700 seq_puts(m, " heap"); 2701 } else if (vma_is_initial_stack(vma)) { 2702 seq_puts(m, " stack"); 2703 } 2704 2705 if (is_vm_hugetlb_page(vma)) 2706 seq_puts(m, " huge"); 2707 2708 /* mmap_lock is held by m_start */ 2709 walk_page_vma(vma, &show_numa_ops, md); 2710 2711 if (!md->pages) 2712 goto out; 2713 2714 if (md->anon) 2715 seq_printf(m, " anon=%lu", md->anon); 2716 2717 if (md->dirty) 2718 seq_printf(m, " dirty=%lu", md->dirty); 2719 2720 if (md->pages != md->anon && md->pages != md->dirty) 2721 seq_printf(m, " mapped=%lu", md->pages); 2722 2723 if (md->mapcount_max > 1) 2724 seq_printf(m, " mapmax=%lu", md->mapcount_max); 2725 2726 if (md->swapcache) 2727 seq_printf(m, " swapcache=%lu", md->swapcache); 2728 2729 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 2730 seq_printf(m, " active=%lu", md->active); 2731 2732 if (md->writeback) 2733 seq_printf(m, " writeback=%lu", md->writeback); 2734 2735 for_each_node_state(nid, N_MEMORY) 2736 if (md->node[nid]) 2737 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 2738 2739 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 2740 out: 2741 seq_putc(m, '\n'); 2742 return 0; 2743 } 2744 2745 static const struct seq_operations proc_pid_numa_maps_op = { 2746 .start = m_start, 2747 .next = m_next, 2748 .stop = m_stop, 2749 .show = show_numa_map, 2750 }; 2751 2752 static int pid_numa_maps_open(struct inode *inode, struct file *file) 2753 { 2754 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 2755 sizeof(struct numa_maps_private)); 2756 } 2757 2758 const struct file_operations proc_pid_numa_maps_operations = { 2759 .open = pid_numa_maps_open, 2760 .read = seq_read, 2761 .llseek = seq_lseek, 2762 .release = proc_map_release, 2763 }; 2764 2765 #endif /* CONFIG_NUMA */ 2766