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) 33void 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 85unsigned long task_vsize(struct mm_struct *mm) 86{ 87 return PAGE_SIZE * mm->total_vm; 88} 89 90unsigned 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 */ 107static 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} 116static void release_task_mempolicy(struct proc_maps_private *priv) 117{ 118 mpol_put(priv->task_mempolicy); 119} 120#else 121static void hold_task_mempolicy(struct proc_maps_private *priv) 122{ 123} 124static void release_task_mempolicy(struct proc_maps_private *priv) 125{ 126} 127#endif 128 129static 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 144static 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 180static 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 189static 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 204static 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 224static 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 235static 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 242static 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 262static void 263show_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 const struct inode *inode = file_user_inode(vma->vm_file); 277 278 dev = inode->i_sb->s_dev; 279 ino = inode->i_ino; 280 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 281 } 282 283 start = vma->vm_start; 284 end = vma->vm_end; 285 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 286 if (mm) 287 anon_name = anon_vma_name(vma); 288 289 /* 290 * Print the dentry name for named mappings, and a 291 * special [heap] marker for the heap: 292 */ 293 if (file) { 294 seq_pad(m, ' '); 295 /* 296 * If user named this anon shared memory via 297 * prctl(PR_SET_VMA ..., use the provided name. 298 */ 299 if (anon_name) 300 seq_printf(m, "[anon_shmem:%s]", anon_name->name); 301 else 302 seq_path(m, file_user_path(file), "\n"); 303 goto done; 304 } 305 306 if (vma->vm_ops && vma->vm_ops->name) { 307 name = vma->vm_ops->name(vma); 308 if (name) 309 goto done; 310 } 311 312 name = arch_vma_name(vma); 313 if (!name) { 314 if (!mm) { 315 name = "[vdso]"; 316 goto done; 317 } 318 319 if (vma_is_initial_heap(vma)) { 320 name = "[heap]"; 321 goto done; 322 } 323 324 if (vma_is_initial_stack(vma)) { 325 name = "[stack]"; 326 goto done; 327 } 328 329 if (anon_name) { 330 seq_pad(m, ' '); 331 seq_printf(m, "[anon:%s]", anon_name->name); 332 } 333 } 334 335done: 336 if (name) { 337 seq_pad(m, ' '); 338 seq_puts(m, name); 339 } 340 seq_putc(m, '\n'); 341} 342 343static int show_map(struct seq_file *m, void *v) 344{ 345 show_map_vma(m, v); 346 return 0; 347} 348 349static const struct seq_operations proc_pid_maps_op = { 350 .start = m_start, 351 .next = m_next, 352 .stop = m_stop, 353 .show = show_map 354}; 355 356static int pid_maps_open(struct inode *inode, struct file *file) 357{ 358 return do_maps_open(inode, file, &proc_pid_maps_op); 359} 360 361const struct file_operations proc_pid_maps_operations = { 362 .open = pid_maps_open, 363 .read = seq_read, 364 .llseek = seq_lseek, 365 .release = proc_map_release, 366}; 367 368/* 369 * Proportional Set Size(PSS): my share of RSS. 370 * 371 * PSS of a process is the count of pages it has in memory, where each 372 * page is divided by the number of processes sharing it. So if a 373 * process has 1000 pages all to itself, and 1000 shared with one other 374 * process, its PSS will be 1500. 375 * 376 * To keep (accumulated) division errors low, we adopt a 64bit 377 * fixed-point pss counter to minimize division errors. So (pss >> 378 * PSS_SHIFT) would be the real byte count. 379 * 380 * A shift of 12 before division means (assuming 4K page size): 381 * - 1M 3-user-pages add up to 8KB errors; 382 * - supports mapcount up to 2^24, or 16M; 383 * - supports PSS up to 2^52 bytes, or 4PB. 384 */ 385#define PSS_SHIFT 12 386 387#ifdef CONFIG_PROC_PAGE_MONITOR 388struct mem_size_stats { 389 unsigned long resident; 390 unsigned long shared_clean; 391 unsigned long shared_dirty; 392 unsigned long private_clean; 393 unsigned long private_dirty; 394 unsigned long referenced; 395 unsigned long anonymous; 396 unsigned long lazyfree; 397 unsigned long anonymous_thp; 398 unsigned long shmem_thp; 399 unsigned long file_thp; 400 unsigned long swap; 401 unsigned long shared_hugetlb; 402 unsigned long private_hugetlb; 403 unsigned long ksm; 404 u64 pss; 405 u64 pss_anon; 406 u64 pss_file; 407 u64 pss_shmem; 408 u64 pss_dirty; 409 u64 pss_locked; 410 u64 swap_pss; 411}; 412 413static void smaps_page_accumulate(struct mem_size_stats *mss, 414 struct folio *folio, unsigned long size, unsigned long pss, 415 bool dirty, bool locked, bool private) 416{ 417 mss->pss += pss; 418 419 if (folio_test_anon(folio)) 420 mss->pss_anon += pss; 421 else if (folio_test_swapbacked(folio)) 422 mss->pss_shmem += pss; 423 else 424 mss->pss_file += pss; 425 426 if (locked) 427 mss->pss_locked += pss; 428 429 if (dirty || folio_test_dirty(folio)) { 430 mss->pss_dirty += pss; 431 if (private) 432 mss->private_dirty += size; 433 else 434 mss->shared_dirty += size; 435 } else { 436 if (private) 437 mss->private_clean += size; 438 else 439 mss->shared_clean += size; 440 } 441} 442 443static void smaps_account(struct mem_size_stats *mss, struct page *page, 444 bool compound, bool young, bool dirty, bool locked, 445 bool migration) 446{ 447 struct folio *folio = page_folio(page); 448 int i, nr = compound ? compound_nr(page) : 1; 449 unsigned long size = nr * PAGE_SIZE; 450 451 /* 452 * First accumulate quantities that depend only on |size| and the type 453 * of the compound page. 454 */ 455 if (folio_test_anon(folio)) { 456 mss->anonymous += size; 457 if (!folio_test_swapbacked(folio) && !dirty && 458 !folio_test_dirty(folio)) 459 mss->lazyfree += size; 460 } 461 462 if (folio_test_ksm(folio)) 463 mss->ksm += size; 464 465 mss->resident += size; 466 /* Accumulate the size in pages that have been accessed. */ 467 if (young || folio_test_young(folio) || folio_test_referenced(folio)) 468 mss->referenced += size; 469 470 /* 471 * Then accumulate quantities that may depend on sharing, or that may 472 * differ page-by-page. 473 * 474 * refcount == 1 guarantees the page is mapped exactly once. 475 * If any subpage of the compound page mapped with PTE it would elevate 476 * the refcount. 477 * 478 * The page_mapcount() is called to get a snapshot of the mapcount. 479 * Without holding the page lock this snapshot can be slightly wrong as 480 * we cannot always read the mapcount atomically. It is not safe to 481 * call page_mapcount() even with PTL held if the page is not mapped, 482 * especially for migration entries. Treat regular migration entries 483 * as mapcount == 1. 484 */ 485 if ((folio_ref_count(folio) == 1) || migration) { 486 smaps_page_accumulate(mss, folio, size, size << PSS_SHIFT, 487 dirty, locked, true); 488 return; 489 } 490 for (i = 0; i < nr; i++, page++) { 491 int mapcount = page_mapcount(page); 492 unsigned long pss = PAGE_SIZE << PSS_SHIFT; 493 if (mapcount >= 2) 494 pss /= mapcount; 495 smaps_page_accumulate(mss, folio, PAGE_SIZE, pss, 496 dirty, locked, mapcount < 2); 497 } 498} 499 500#ifdef CONFIG_SHMEM 501static int smaps_pte_hole(unsigned long addr, unsigned long end, 502 __always_unused int depth, struct mm_walk *walk) 503{ 504 struct mem_size_stats *mss = walk->private; 505 struct vm_area_struct *vma = walk->vma; 506 507 mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping, 508 linear_page_index(vma, addr), 509 linear_page_index(vma, end)); 510 511 return 0; 512} 513#else 514#define smaps_pte_hole NULL 515#endif /* CONFIG_SHMEM */ 516 517static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk) 518{ 519#ifdef CONFIG_SHMEM 520 if (walk->ops->pte_hole) { 521 /* depth is not used */ 522 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk); 523 } 524#endif 525} 526 527static void smaps_pte_entry(pte_t *pte, unsigned long addr, 528 struct mm_walk *walk) 529{ 530 struct mem_size_stats *mss = walk->private; 531 struct vm_area_struct *vma = walk->vma; 532 bool locked = !!(vma->vm_flags & VM_LOCKED); 533 struct page *page = NULL; 534 bool migration = false, young = false, dirty = false; 535 pte_t ptent = ptep_get(pte); 536 537 if (pte_present(ptent)) { 538 page = vm_normal_page(vma, addr, ptent); 539 young = pte_young(ptent); 540 dirty = pte_dirty(ptent); 541 } else if (is_swap_pte(ptent)) { 542 swp_entry_t swpent = pte_to_swp_entry(ptent); 543 544 if (!non_swap_entry(swpent)) { 545 int mapcount; 546 547 mss->swap += PAGE_SIZE; 548 mapcount = swp_swapcount(swpent); 549 if (mapcount >= 2) { 550 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 551 552 do_div(pss_delta, mapcount); 553 mss->swap_pss += pss_delta; 554 } else { 555 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 556 } 557 } else if (is_pfn_swap_entry(swpent)) { 558 if (is_migration_entry(swpent)) 559 migration = true; 560 page = pfn_swap_entry_to_page(swpent); 561 } 562 } else { 563 smaps_pte_hole_lookup(addr, walk); 564 return; 565 } 566 567 if (!page) 568 return; 569 570 smaps_account(mss, page, false, young, dirty, locked, migration); 571} 572 573#ifdef CONFIG_TRANSPARENT_HUGEPAGE 574static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 575 struct mm_walk *walk) 576{ 577 struct mem_size_stats *mss = walk->private; 578 struct vm_area_struct *vma = walk->vma; 579 bool locked = !!(vma->vm_flags & VM_LOCKED); 580 struct page *page = NULL; 581 struct folio *folio; 582 bool migration = false; 583 584 if (pmd_present(*pmd)) { 585 page = vm_normal_page_pmd(vma, addr, *pmd); 586 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { 587 swp_entry_t entry = pmd_to_swp_entry(*pmd); 588 589 if (is_migration_entry(entry)) { 590 migration = true; 591 page = pfn_swap_entry_to_page(entry); 592 } 593 } 594 if (IS_ERR_OR_NULL(page)) 595 return; 596 folio = page_folio(page); 597 if (folio_test_anon(folio)) 598 mss->anonymous_thp += HPAGE_PMD_SIZE; 599 else if (folio_test_swapbacked(folio)) 600 mss->shmem_thp += HPAGE_PMD_SIZE; 601 else if (folio_is_zone_device(folio)) 602 /* pass */; 603 else 604 mss->file_thp += HPAGE_PMD_SIZE; 605 606 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), 607 locked, migration); 608} 609#else 610static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 611 struct mm_walk *walk) 612{ 613} 614#endif 615 616static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 617 struct mm_walk *walk) 618{ 619 struct vm_area_struct *vma = walk->vma; 620 pte_t *pte; 621 spinlock_t *ptl; 622 623 ptl = pmd_trans_huge_lock(pmd, vma); 624 if (ptl) { 625 smaps_pmd_entry(pmd, addr, walk); 626 spin_unlock(ptl); 627 goto out; 628 } 629 630 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 631 if (!pte) { 632 walk->action = ACTION_AGAIN; 633 return 0; 634 } 635 for (; addr != end; pte++, addr += PAGE_SIZE) 636 smaps_pte_entry(pte, addr, walk); 637 pte_unmap_unlock(pte - 1, ptl); 638out: 639 cond_resched(); 640 return 0; 641} 642 643static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 644{ 645 /* 646 * Don't forget to update Documentation/ on changes. 647 */ 648 static const char mnemonics[BITS_PER_LONG][2] = { 649 /* 650 * In case if we meet a flag we don't know about. 651 */ 652 [0 ... (BITS_PER_LONG-1)] = "??", 653 654 [ilog2(VM_READ)] = "rd", 655 [ilog2(VM_WRITE)] = "wr", 656 [ilog2(VM_EXEC)] = "ex", 657 [ilog2(VM_SHARED)] = "sh", 658 [ilog2(VM_MAYREAD)] = "mr", 659 [ilog2(VM_MAYWRITE)] = "mw", 660 [ilog2(VM_MAYEXEC)] = "me", 661 [ilog2(VM_MAYSHARE)] = "ms", 662 [ilog2(VM_GROWSDOWN)] = "gd", 663 [ilog2(VM_PFNMAP)] = "pf", 664 [ilog2(VM_LOCKED)] = "lo", 665 [ilog2(VM_IO)] = "io", 666 [ilog2(VM_SEQ_READ)] = "sr", 667 [ilog2(VM_RAND_READ)] = "rr", 668 [ilog2(VM_DONTCOPY)] = "dc", 669 [ilog2(VM_DONTEXPAND)] = "de", 670 [ilog2(VM_LOCKONFAULT)] = "lf", 671 [ilog2(VM_ACCOUNT)] = "ac", 672 [ilog2(VM_NORESERVE)] = "nr", 673 [ilog2(VM_HUGETLB)] = "ht", 674 [ilog2(VM_SYNC)] = "sf", 675 [ilog2(VM_ARCH_1)] = "ar", 676 [ilog2(VM_WIPEONFORK)] = "wf", 677 [ilog2(VM_DONTDUMP)] = "dd", 678#ifdef CONFIG_ARM64_BTI 679 [ilog2(VM_ARM64_BTI)] = "bt", 680#endif 681#ifdef CONFIG_MEM_SOFT_DIRTY 682 [ilog2(VM_SOFTDIRTY)] = "sd", 683#endif 684 [ilog2(VM_MIXEDMAP)] = "mm", 685 [ilog2(VM_HUGEPAGE)] = "hg", 686 [ilog2(VM_NOHUGEPAGE)] = "nh", 687 [ilog2(VM_MERGEABLE)] = "mg", 688 [ilog2(VM_UFFD_MISSING)]= "um", 689 [ilog2(VM_UFFD_WP)] = "uw", 690#ifdef CONFIG_ARM64_MTE 691 [ilog2(VM_MTE)] = "mt", 692 [ilog2(VM_MTE_ALLOWED)] = "", 693#endif 694#ifdef CONFIG_ARCH_HAS_PKEYS 695 /* These come out via ProtectionKey: */ 696 [ilog2(VM_PKEY_BIT0)] = "", 697 [ilog2(VM_PKEY_BIT1)] = "", 698 [ilog2(VM_PKEY_BIT2)] = "", 699 [ilog2(VM_PKEY_BIT3)] = "", 700#if VM_PKEY_BIT4 701 [ilog2(VM_PKEY_BIT4)] = "", 702#endif 703#endif /* CONFIG_ARCH_HAS_PKEYS */ 704#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR 705 [ilog2(VM_UFFD_MINOR)] = "ui", 706#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ 707#ifdef CONFIG_X86_USER_SHADOW_STACK 708 [ilog2(VM_SHADOW_STACK)] = "ss", 709#endif 710 }; 711 size_t i; 712 713 seq_puts(m, "VmFlags: "); 714 for (i = 0; i < BITS_PER_LONG; i++) { 715 if (!mnemonics[i][0]) 716 continue; 717 if (vma->vm_flags & (1UL << i)) { 718 seq_putc(m, mnemonics[i][0]); 719 seq_putc(m, mnemonics[i][1]); 720 seq_putc(m, ' '); 721 } 722 } 723 seq_putc(m, '\n'); 724} 725 726#ifdef CONFIG_HUGETLB_PAGE 727static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 728 unsigned long addr, unsigned long end, 729 struct mm_walk *walk) 730{ 731 struct mem_size_stats *mss = walk->private; 732 struct vm_area_struct *vma = walk->vma; 733 pte_t ptent = huge_ptep_get(pte); 734 struct folio *folio = NULL; 735 736 if (pte_present(ptent)) { 737 folio = page_folio(pte_page(ptent)); 738 } else if (is_swap_pte(ptent)) { 739 swp_entry_t swpent = pte_to_swp_entry(ptent); 740 741 if (is_pfn_swap_entry(swpent)) 742 folio = pfn_swap_entry_folio(swpent); 743 } 744 if (folio) { 745 if (folio_likely_mapped_shared(folio) || 746 hugetlb_pmd_shared(pte)) 747 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 748 else 749 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 750 } 751 return 0; 752} 753#else 754#define smaps_hugetlb_range NULL 755#endif /* HUGETLB_PAGE */ 756 757static const struct mm_walk_ops smaps_walk_ops = { 758 .pmd_entry = smaps_pte_range, 759 .hugetlb_entry = smaps_hugetlb_range, 760 .walk_lock = PGWALK_RDLOCK, 761}; 762 763static const struct mm_walk_ops smaps_shmem_walk_ops = { 764 .pmd_entry = smaps_pte_range, 765 .hugetlb_entry = smaps_hugetlb_range, 766 .pte_hole = smaps_pte_hole, 767 .walk_lock = PGWALK_RDLOCK, 768}; 769 770/* 771 * Gather mem stats from @vma with the indicated beginning 772 * address @start, and keep them in @mss. 773 * 774 * Use vm_start of @vma as the beginning address if @start is 0. 775 */ 776static void smap_gather_stats(struct vm_area_struct *vma, 777 struct mem_size_stats *mss, unsigned long start) 778{ 779 const struct mm_walk_ops *ops = &smaps_walk_ops; 780 781 /* Invalid start */ 782 if (start >= vma->vm_end) 783 return; 784 785 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 786 /* 787 * For shared or readonly shmem mappings we know that all 788 * swapped out pages belong to the shmem object, and we can 789 * obtain the swap value much more efficiently. For private 790 * writable mappings, we might have COW pages that are 791 * not affected by the parent swapped out pages of the shmem 792 * object, so we have to distinguish them during the page walk. 793 * Unless we know that the shmem object (or the part mapped by 794 * our VMA) has no swapped out pages at all. 795 */ 796 unsigned long shmem_swapped = shmem_swap_usage(vma); 797 798 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 799 !(vma->vm_flags & VM_WRITE))) { 800 mss->swap += shmem_swapped; 801 } else { 802 ops = &smaps_shmem_walk_ops; 803 } 804 } 805 806 /* mmap_lock is held in m_start */ 807 if (!start) 808 walk_page_vma(vma, ops, mss); 809 else 810 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); 811} 812 813#define SEQ_PUT_DEC(str, val) \ 814 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 815 816/* Show the contents common for smaps and smaps_rollup */ 817static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 818 bool rollup_mode) 819{ 820 SEQ_PUT_DEC("Rss: ", mss->resident); 821 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 822 SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT); 823 if (rollup_mode) { 824 /* 825 * These are meaningful only for smaps_rollup, otherwise two of 826 * them are zero, and the other one is the same as Pss. 827 */ 828 SEQ_PUT_DEC(" kB\nPss_Anon: ", 829 mss->pss_anon >> PSS_SHIFT); 830 SEQ_PUT_DEC(" kB\nPss_File: ", 831 mss->pss_file >> PSS_SHIFT); 832 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 833 mss->pss_shmem >> PSS_SHIFT); 834 } 835 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 836 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 837 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 838 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 839 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 840 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 841 SEQ_PUT_DEC(" kB\nKSM: ", mss->ksm); 842 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 843 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 844 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 845 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 846 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 847 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 848 mss->private_hugetlb >> 10, 7); 849 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 850 SEQ_PUT_DEC(" kB\nSwapPss: ", 851 mss->swap_pss >> PSS_SHIFT); 852 SEQ_PUT_DEC(" kB\nLocked: ", 853 mss->pss_locked >> PSS_SHIFT); 854 seq_puts(m, " kB\n"); 855} 856 857static int show_smap(struct seq_file *m, void *v) 858{ 859 struct vm_area_struct *vma = v; 860 struct mem_size_stats mss = {}; 861 862 smap_gather_stats(vma, &mss, 0); 863 864 show_map_vma(m, vma); 865 866 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 867 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 868 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 869 seq_puts(m, " kB\n"); 870 871 __show_smap(m, &mss, false); 872 873 seq_printf(m, "THPeligible: %8u\n", 874 !!thp_vma_allowable_orders(vma, vma->vm_flags, 875 TVA_SMAPS | TVA_ENFORCE_SYSFS, THP_ORDERS_ALL)); 876 877 if (arch_pkeys_enabled()) 878 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 879 show_smap_vma_flags(m, vma); 880 881 return 0; 882} 883 884static int show_smaps_rollup(struct seq_file *m, void *v) 885{ 886 struct proc_maps_private *priv = m->private; 887 struct mem_size_stats mss = {}; 888 struct mm_struct *mm = priv->mm; 889 struct vm_area_struct *vma; 890 unsigned long vma_start = 0, last_vma_end = 0; 891 int ret = 0; 892 VMA_ITERATOR(vmi, mm, 0); 893 894 priv->task = get_proc_task(priv->inode); 895 if (!priv->task) 896 return -ESRCH; 897 898 if (!mm || !mmget_not_zero(mm)) { 899 ret = -ESRCH; 900 goto out_put_task; 901 } 902 903 ret = mmap_read_lock_killable(mm); 904 if (ret) 905 goto out_put_mm; 906 907 hold_task_mempolicy(priv); 908 vma = vma_next(&vmi); 909 910 if (unlikely(!vma)) 911 goto empty_set; 912 913 vma_start = vma->vm_start; 914 do { 915 smap_gather_stats(vma, &mss, 0); 916 last_vma_end = vma->vm_end; 917 918 /* 919 * Release mmap_lock temporarily if someone wants to 920 * access it for write request. 921 */ 922 if (mmap_lock_is_contended(mm)) { 923 vma_iter_invalidate(&vmi); 924 mmap_read_unlock(mm); 925 ret = mmap_read_lock_killable(mm); 926 if (ret) { 927 release_task_mempolicy(priv); 928 goto out_put_mm; 929 } 930 931 /* 932 * After dropping the lock, there are four cases to 933 * consider. See the following example for explanation. 934 * 935 * +------+------+-----------+ 936 * | VMA1 | VMA2 | VMA3 | 937 * +------+------+-----------+ 938 * | | | | 939 * 4k 8k 16k 400k 940 * 941 * Suppose we drop the lock after reading VMA2 due to 942 * contention, then we get: 943 * 944 * last_vma_end = 16k 945 * 946 * 1) VMA2 is freed, but VMA3 exists: 947 * 948 * vma_next(vmi) will return VMA3. 949 * In this case, just continue from VMA3. 950 * 951 * 2) VMA2 still exists: 952 * 953 * vma_next(vmi) will return VMA3. 954 * In this case, just continue from VMA3. 955 * 956 * 3) No more VMAs can be found: 957 * 958 * vma_next(vmi) will return NULL. 959 * No more things to do, just break. 960 * 961 * 4) (last_vma_end - 1) is the middle of a vma (VMA'): 962 * 963 * vma_next(vmi) will return VMA' whose range 964 * contains last_vma_end. 965 * Iterate VMA' from last_vma_end. 966 */ 967 vma = vma_next(&vmi); 968 /* Case 3 above */ 969 if (!vma) 970 break; 971 972 /* Case 1 and 2 above */ 973 if (vma->vm_start >= last_vma_end) { 974 smap_gather_stats(vma, &mss, 0); 975 last_vma_end = vma->vm_end; 976 continue; 977 } 978 979 /* Case 4 above */ 980 if (vma->vm_end > last_vma_end) { 981 smap_gather_stats(vma, &mss, last_vma_end); 982 last_vma_end = vma->vm_end; 983 } 984 } 985 } for_each_vma(vmi, vma); 986 987empty_set: 988 show_vma_header_prefix(m, vma_start, last_vma_end, 0, 0, 0, 0); 989 seq_pad(m, ' '); 990 seq_puts(m, "[rollup]\n"); 991 992 __show_smap(m, &mss, true); 993 994 release_task_mempolicy(priv); 995 mmap_read_unlock(mm); 996 997out_put_mm: 998 mmput(mm); 999out_put_task: 1000 put_task_struct(priv->task); 1001 priv->task = NULL; 1002 1003 return ret; 1004} 1005#undef SEQ_PUT_DEC 1006 1007static const struct seq_operations proc_pid_smaps_op = { 1008 .start = m_start, 1009 .next = m_next, 1010 .stop = m_stop, 1011 .show = show_smap 1012}; 1013 1014static int pid_smaps_open(struct inode *inode, struct file *file) 1015{ 1016 return do_maps_open(inode, file, &proc_pid_smaps_op); 1017} 1018 1019static int smaps_rollup_open(struct inode *inode, struct file *file) 1020{ 1021 int ret; 1022 struct proc_maps_private *priv; 1023 1024 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 1025 if (!priv) 1026 return -ENOMEM; 1027 1028 ret = single_open(file, show_smaps_rollup, priv); 1029 if (ret) 1030 goto out_free; 1031 1032 priv->inode = inode; 1033 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 1034 if (IS_ERR(priv->mm)) { 1035 ret = PTR_ERR(priv->mm); 1036 1037 single_release(inode, file); 1038 goto out_free; 1039 } 1040 1041 return 0; 1042 1043out_free: 1044 kfree(priv); 1045 return ret; 1046} 1047 1048static int smaps_rollup_release(struct inode *inode, struct file *file) 1049{ 1050 struct seq_file *seq = file->private_data; 1051 struct proc_maps_private *priv = seq->private; 1052 1053 if (priv->mm) 1054 mmdrop(priv->mm); 1055 1056 kfree(priv); 1057 return single_release(inode, file); 1058} 1059 1060const struct file_operations proc_pid_smaps_operations = { 1061 .open = pid_smaps_open, 1062 .read = seq_read, 1063 .llseek = seq_lseek, 1064 .release = proc_map_release, 1065}; 1066 1067const struct file_operations proc_pid_smaps_rollup_operations = { 1068 .open = smaps_rollup_open, 1069 .read = seq_read, 1070 .llseek = seq_lseek, 1071 .release = smaps_rollup_release, 1072}; 1073 1074enum clear_refs_types { 1075 CLEAR_REFS_ALL = 1, 1076 CLEAR_REFS_ANON, 1077 CLEAR_REFS_MAPPED, 1078 CLEAR_REFS_SOFT_DIRTY, 1079 CLEAR_REFS_MM_HIWATER_RSS, 1080 CLEAR_REFS_LAST, 1081}; 1082 1083struct clear_refs_private { 1084 enum clear_refs_types type; 1085}; 1086 1087#ifdef CONFIG_MEM_SOFT_DIRTY 1088 1089static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1090{ 1091 struct page *page; 1092 1093 if (!pte_write(pte)) 1094 return false; 1095 if (!is_cow_mapping(vma->vm_flags)) 1096 return false; 1097 if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))) 1098 return false; 1099 page = vm_normal_page(vma, addr, pte); 1100 if (!page) 1101 return false; 1102 return page_maybe_dma_pinned(page); 1103} 1104 1105static inline void clear_soft_dirty(struct vm_area_struct *vma, 1106 unsigned long addr, pte_t *pte) 1107{ 1108 /* 1109 * The soft-dirty tracker uses #PF-s to catch writes 1110 * to pages, so write-protect the pte as well. See the 1111 * Documentation/admin-guide/mm/soft-dirty.rst for full description 1112 * of how soft-dirty works. 1113 */ 1114 pte_t ptent = ptep_get(pte); 1115 1116 if (pte_present(ptent)) { 1117 pte_t old_pte; 1118 1119 if (pte_is_pinned(vma, addr, ptent)) 1120 return; 1121 old_pte = ptep_modify_prot_start(vma, addr, pte); 1122 ptent = pte_wrprotect(old_pte); 1123 ptent = pte_clear_soft_dirty(ptent); 1124 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1125 } else if (is_swap_pte(ptent)) { 1126 ptent = pte_swp_clear_soft_dirty(ptent); 1127 set_pte_at(vma->vm_mm, addr, pte, ptent); 1128 } 1129} 1130#else 1131static inline void clear_soft_dirty(struct vm_area_struct *vma, 1132 unsigned long addr, pte_t *pte) 1133{ 1134} 1135#endif 1136 1137#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 1138static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1139 unsigned long addr, pmd_t *pmdp) 1140{ 1141 pmd_t old, pmd = *pmdp; 1142 1143 if (pmd_present(pmd)) { 1144 /* See comment in change_huge_pmd() */ 1145 old = pmdp_invalidate(vma, addr, pmdp); 1146 if (pmd_dirty(old)) 1147 pmd = pmd_mkdirty(pmd); 1148 if (pmd_young(old)) 1149 pmd = pmd_mkyoung(pmd); 1150 1151 pmd = pmd_wrprotect(pmd); 1152 pmd = pmd_clear_soft_dirty(pmd); 1153 1154 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1155 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1156 pmd = pmd_swp_clear_soft_dirty(pmd); 1157 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1158 } 1159} 1160#else 1161static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1162 unsigned long addr, pmd_t *pmdp) 1163{ 1164} 1165#endif 1166 1167static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1168 unsigned long end, struct mm_walk *walk) 1169{ 1170 struct clear_refs_private *cp = walk->private; 1171 struct vm_area_struct *vma = walk->vma; 1172 pte_t *pte, ptent; 1173 spinlock_t *ptl; 1174 struct folio *folio; 1175 1176 ptl = pmd_trans_huge_lock(pmd, vma); 1177 if (ptl) { 1178 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1179 clear_soft_dirty_pmd(vma, addr, pmd); 1180 goto out; 1181 } 1182 1183 if (!pmd_present(*pmd)) 1184 goto out; 1185 1186 folio = pmd_folio(*pmd); 1187 1188 /* Clear accessed and referenced bits. */ 1189 pmdp_test_and_clear_young(vma, addr, pmd); 1190 folio_test_clear_young(folio); 1191 folio_clear_referenced(folio); 1192out: 1193 spin_unlock(ptl); 1194 return 0; 1195 } 1196 1197 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1198 if (!pte) { 1199 walk->action = ACTION_AGAIN; 1200 return 0; 1201 } 1202 for (; addr != end; pte++, addr += PAGE_SIZE) { 1203 ptent = ptep_get(pte); 1204 1205 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1206 clear_soft_dirty(vma, addr, pte); 1207 continue; 1208 } 1209 1210 if (!pte_present(ptent)) 1211 continue; 1212 1213 folio = vm_normal_folio(vma, addr, ptent); 1214 if (!folio) 1215 continue; 1216 1217 /* Clear accessed and referenced bits. */ 1218 ptep_test_and_clear_young(vma, addr, pte); 1219 folio_test_clear_young(folio); 1220 folio_clear_referenced(folio); 1221 } 1222 pte_unmap_unlock(pte - 1, ptl); 1223 cond_resched(); 1224 return 0; 1225} 1226 1227static int clear_refs_test_walk(unsigned long start, unsigned long end, 1228 struct mm_walk *walk) 1229{ 1230 struct clear_refs_private *cp = walk->private; 1231 struct vm_area_struct *vma = walk->vma; 1232 1233 if (vma->vm_flags & VM_PFNMAP) 1234 return 1; 1235 1236 /* 1237 * Writing 1 to /proc/pid/clear_refs affects all pages. 1238 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1239 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1240 * Writing 4 to /proc/pid/clear_refs affects all pages. 1241 */ 1242 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1243 return 1; 1244 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1245 return 1; 1246 return 0; 1247} 1248 1249static const struct mm_walk_ops clear_refs_walk_ops = { 1250 .pmd_entry = clear_refs_pte_range, 1251 .test_walk = clear_refs_test_walk, 1252 .walk_lock = PGWALK_WRLOCK, 1253}; 1254 1255static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1256 size_t count, loff_t *ppos) 1257{ 1258 struct task_struct *task; 1259 char buffer[PROC_NUMBUF] = {}; 1260 struct mm_struct *mm; 1261 struct vm_area_struct *vma; 1262 enum clear_refs_types type; 1263 int itype; 1264 int rv; 1265 1266 if (count > sizeof(buffer) - 1) 1267 count = sizeof(buffer) - 1; 1268 if (copy_from_user(buffer, buf, count)) 1269 return -EFAULT; 1270 rv = kstrtoint(strstrip(buffer), 10, &itype); 1271 if (rv < 0) 1272 return rv; 1273 type = (enum clear_refs_types)itype; 1274 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1275 return -EINVAL; 1276 1277 task = get_proc_task(file_inode(file)); 1278 if (!task) 1279 return -ESRCH; 1280 mm = get_task_mm(task); 1281 if (mm) { 1282 VMA_ITERATOR(vmi, mm, 0); 1283 struct mmu_notifier_range range; 1284 struct clear_refs_private cp = { 1285 .type = type, 1286 }; 1287 1288 if (mmap_write_lock_killable(mm)) { 1289 count = -EINTR; 1290 goto out_mm; 1291 } 1292 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1293 /* 1294 * Writing 5 to /proc/pid/clear_refs resets the peak 1295 * resident set size to this mm's current rss value. 1296 */ 1297 reset_mm_hiwater_rss(mm); 1298 goto out_unlock; 1299 } 1300 1301 if (type == CLEAR_REFS_SOFT_DIRTY) { 1302 for_each_vma(vmi, vma) { 1303 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1304 continue; 1305 vm_flags_clear(vma, VM_SOFTDIRTY); 1306 vma_set_page_prot(vma); 1307 } 1308 1309 inc_tlb_flush_pending(mm); 1310 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1311 0, mm, 0, -1UL); 1312 mmu_notifier_invalidate_range_start(&range); 1313 } 1314 walk_page_range(mm, 0, -1, &clear_refs_walk_ops, &cp); 1315 if (type == CLEAR_REFS_SOFT_DIRTY) { 1316 mmu_notifier_invalidate_range_end(&range); 1317 flush_tlb_mm(mm); 1318 dec_tlb_flush_pending(mm); 1319 } 1320out_unlock: 1321 mmap_write_unlock(mm); 1322out_mm: 1323 mmput(mm); 1324 } 1325 put_task_struct(task); 1326 1327 return count; 1328} 1329 1330const struct file_operations proc_clear_refs_operations = { 1331 .write = clear_refs_write, 1332 .llseek = noop_llseek, 1333}; 1334 1335typedef struct { 1336 u64 pme; 1337} pagemap_entry_t; 1338 1339struct pagemapread { 1340 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1341 pagemap_entry_t *buffer; 1342 bool show_pfn; 1343}; 1344 1345#define PAGEMAP_WALK_SIZE (PMD_SIZE) 1346#define PAGEMAP_WALK_MASK (PMD_MASK) 1347 1348#define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1349#define PM_PFRAME_BITS 55 1350#define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1351#define PM_SOFT_DIRTY BIT_ULL(55) 1352#define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1353#define PM_UFFD_WP BIT_ULL(57) 1354#define PM_FILE BIT_ULL(61) 1355#define PM_SWAP BIT_ULL(62) 1356#define PM_PRESENT BIT_ULL(63) 1357 1358#define PM_END_OF_BUFFER 1 1359 1360static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1361{ 1362 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1363} 1364 1365static int add_to_pagemap(pagemap_entry_t *pme, struct pagemapread *pm) 1366{ 1367 pm->buffer[pm->pos++] = *pme; 1368 if (pm->pos >= pm->len) 1369 return PM_END_OF_BUFFER; 1370 return 0; 1371} 1372 1373static int pagemap_pte_hole(unsigned long start, unsigned long end, 1374 __always_unused int depth, struct mm_walk *walk) 1375{ 1376 struct pagemapread *pm = walk->private; 1377 unsigned long addr = start; 1378 int err = 0; 1379 1380 while (addr < end) { 1381 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1382 pagemap_entry_t pme = make_pme(0, 0); 1383 /* End of address space hole, which we mark as non-present. */ 1384 unsigned long hole_end; 1385 1386 if (vma) 1387 hole_end = min(end, vma->vm_start); 1388 else 1389 hole_end = end; 1390 1391 for (; addr < hole_end; addr += PAGE_SIZE) { 1392 err = add_to_pagemap(&pme, pm); 1393 if (err) 1394 goto out; 1395 } 1396 1397 if (!vma) 1398 break; 1399 1400 /* Addresses in the VMA. */ 1401 if (vma->vm_flags & VM_SOFTDIRTY) 1402 pme = make_pme(0, PM_SOFT_DIRTY); 1403 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1404 err = add_to_pagemap(&pme, pm); 1405 if (err) 1406 goto out; 1407 } 1408 } 1409out: 1410 return err; 1411} 1412 1413static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1414 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1415{ 1416 u64 frame = 0, flags = 0; 1417 struct page *page = NULL; 1418 bool migration = false; 1419 1420 if (pte_present(pte)) { 1421 if (pm->show_pfn) 1422 frame = pte_pfn(pte); 1423 flags |= PM_PRESENT; 1424 page = vm_normal_page(vma, addr, pte); 1425 if (pte_soft_dirty(pte)) 1426 flags |= PM_SOFT_DIRTY; 1427 if (pte_uffd_wp(pte)) 1428 flags |= PM_UFFD_WP; 1429 } else if (is_swap_pte(pte)) { 1430 swp_entry_t entry; 1431 if (pte_swp_soft_dirty(pte)) 1432 flags |= PM_SOFT_DIRTY; 1433 if (pte_swp_uffd_wp(pte)) 1434 flags |= PM_UFFD_WP; 1435 entry = pte_to_swp_entry(pte); 1436 if (pm->show_pfn) { 1437 pgoff_t offset; 1438 /* 1439 * For PFN swap offsets, keeping the offset field 1440 * to be PFN only to be compatible with old smaps. 1441 */ 1442 if (is_pfn_swap_entry(entry)) 1443 offset = swp_offset_pfn(entry); 1444 else 1445 offset = swp_offset(entry); 1446 frame = swp_type(entry) | 1447 (offset << MAX_SWAPFILES_SHIFT); 1448 } 1449 flags |= PM_SWAP; 1450 migration = is_migration_entry(entry); 1451 if (is_pfn_swap_entry(entry)) 1452 page = pfn_swap_entry_to_page(entry); 1453 if (pte_marker_entry_uffd_wp(entry)) 1454 flags |= PM_UFFD_WP; 1455 } 1456 1457 if (page && !PageAnon(page)) 1458 flags |= PM_FILE; 1459 if (page && !migration && page_mapcount(page) == 1) 1460 flags |= PM_MMAP_EXCLUSIVE; 1461 if (vma->vm_flags & VM_SOFTDIRTY) 1462 flags |= PM_SOFT_DIRTY; 1463 1464 return make_pme(frame, flags); 1465} 1466 1467static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1468 struct mm_walk *walk) 1469{ 1470 struct vm_area_struct *vma = walk->vma; 1471 struct pagemapread *pm = walk->private; 1472 spinlock_t *ptl; 1473 pte_t *pte, *orig_pte; 1474 int err = 0; 1475#ifdef CONFIG_TRANSPARENT_HUGEPAGE 1476 bool migration = false; 1477 1478 ptl = pmd_trans_huge_lock(pmdp, vma); 1479 if (ptl) { 1480 u64 flags = 0, frame = 0; 1481 pmd_t pmd = *pmdp; 1482 struct page *page = NULL; 1483 1484 if (vma->vm_flags & VM_SOFTDIRTY) 1485 flags |= PM_SOFT_DIRTY; 1486 1487 if (pmd_present(pmd)) { 1488 page = pmd_page(pmd); 1489 1490 flags |= PM_PRESENT; 1491 if (pmd_soft_dirty(pmd)) 1492 flags |= PM_SOFT_DIRTY; 1493 if (pmd_uffd_wp(pmd)) 1494 flags |= PM_UFFD_WP; 1495 if (pm->show_pfn) 1496 frame = pmd_pfn(pmd) + 1497 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1498 } 1499#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1500 else if (is_swap_pmd(pmd)) { 1501 swp_entry_t entry = pmd_to_swp_entry(pmd); 1502 unsigned long offset; 1503 1504 if (pm->show_pfn) { 1505 if (is_pfn_swap_entry(entry)) 1506 offset = swp_offset_pfn(entry); 1507 else 1508 offset = swp_offset(entry); 1509 offset = offset + 1510 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1511 frame = swp_type(entry) | 1512 (offset << MAX_SWAPFILES_SHIFT); 1513 } 1514 flags |= PM_SWAP; 1515 if (pmd_swp_soft_dirty(pmd)) 1516 flags |= PM_SOFT_DIRTY; 1517 if (pmd_swp_uffd_wp(pmd)) 1518 flags |= PM_UFFD_WP; 1519 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1520 migration = is_migration_entry(entry); 1521 page = pfn_swap_entry_to_page(entry); 1522 } 1523#endif 1524 1525 if (page && !migration && page_mapcount(page) == 1) 1526 flags |= PM_MMAP_EXCLUSIVE; 1527 1528 for (; addr != end; addr += PAGE_SIZE) { 1529 pagemap_entry_t pme = make_pme(frame, flags); 1530 1531 err = add_to_pagemap(&pme, pm); 1532 if (err) 1533 break; 1534 if (pm->show_pfn) { 1535 if (flags & PM_PRESENT) 1536 frame++; 1537 else if (flags & PM_SWAP) 1538 frame += (1 << MAX_SWAPFILES_SHIFT); 1539 } 1540 } 1541 spin_unlock(ptl); 1542 return err; 1543 } 1544#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1545 1546 /* 1547 * We can assume that @vma always points to a valid one and @end never 1548 * goes beyond vma->vm_end. 1549 */ 1550 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1551 if (!pte) { 1552 walk->action = ACTION_AGAIN; 1553 return err; 1554 } 1555 for (; addr < end; pte++, addr += PAGE_SIZE) { 1556 pagemap_entry_t pme; 1557 1558 pme = pte_to_pagemap_entry(pm, vma, addr, ptep_get(pte)); 1559 err = add_to_pagemap(&pme, pm); 1560 if (err) 1561 break; 1562 } 1563 pte_unmap_unlock(orig_pte, ptl); 1564 1565 cond_resched(); 1566 1567 return err; 1568} 1569 1570#ifdef CONFIG_HUGETLB_PAGE 1571/* This function walks within one hugetlb entry in the single call */ 1572static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1573 unsigned long addr, unsigned long end, 1574 struct mm_walk *walk) 1575{ 1576 struct pagemapread *pm = walk->private; 1577 struct vm_area_struct *vma = walk->vma; 1578 u64 flags = 0, frame = 0; 1579 int err = 0; 1580 pte_t pte; 1581 1582 if (vma->vm_flags & VM_SOFTDIRTY) 1583 flags |= PM_SOFT_DIRTY; 1584 1585 pte = huge_ptep_get(ptep); 1586 if (pte_present(pte)) { 1587 struct folio *folio = page_folio(pte_page(pte)); 1588 1589 if (!folio_test_anon(folio)) 1590 flags |= PM_FILE; 1591 1592 if (!folio_likely_mapped_shared(folio) && 1593 !hugetlb_pmd_shared(ptep)) 1594 flags |= PM_MMAP_EXCLUSIVE; 1595 1596 if (huge_pte_uffd_wp(pte)) 1597 flags |= PM_UFFD_WP; 1598 1599 flags |= PM_PRESENT; 1600 if (pm->show_pfn) 1601 frame = pte_pfn(pte) + 1602 ((addr & ~hmask) >> PAGE_SHIFT); 1603 } else if (pte_swp_uffd_wp_any(pte)) { 1604 flags |= PM_UFFD_WP; 1605 } 1606 1607 for (; addr != end; addr += PAGE_SIZE) { 1608 pagemap_entry_t pme = make_pme(frame, flags); 1609 1610 err = add_to_pagemap(&pme, pm); 1611 if (err) 1612 return err; 1613 if (pm->show_pfn && (flags & PM_PRESENT)) 1614 frame++; 1615 } 1616 1617 cond_resched(); 1618 1619 return err; 1620} 1621#else 1622#define pagemap_hugetlb_range NULL 1623#endif /* HUGETLB_PAGE */ 1624 1625static const struct mm_walk_ops pagemap_ops = { 1626 .pmd_entry = pagemap_pmd_range, 1627 .pte_hole = pagemap_pte_hole, 1628 .hugetlb_entry = pagemap_hugetlb_range, 1629 .walk_lock = PGWALK_RDLOCK, 1630}; 1631 1632/* 1633 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1634 * 1635 * For each page in the address space, this file contains one 64-bit entry 1636 * consisting of the following: 1637 * 1638 * Bits 0-54 page frame number (PFN) if present 1639 * Bits 0-4 swap type if swapped 1640 * Bits 5-54 swap offset if swapped 1641 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1642 * Bit 56 page exclusively mapped 1643 * Bit 57 pte is uffd-wp write-protected 1644 * Bits 58-60 zero 1645 * Bit 61 page is file-page or shared-anon 1646 * Bit 62 page swapped 1647 * Bit 63 page present 1648 * 1649 * If the page is not present but in swap, then the PFN contains an 1650 * encoding of the swap file number and the page's offset into the 1651 * swap. Unmapped pages return a null PFN. This allows determining 1652 * precisely which pages are mapped (or in swap) and comparing mapped 1653 * pages between processes. 1654 * 1655 * Efficient users of this interface will use /proc/pid/maps to 1656 * determine which areas of memory are actually mapped and llseek to 1657 * skip over unmapped regions. 1658 */ 1659static ssize_t pagemap_read(struct file *file, char __user *buf, 1660 size_t count, loff_t *ppos) 1661{ 1662 struct mm_struct *mm = file->private_data; 1663 struct pagemapread pm; 1664 unsigned long src; 1665 unsigned long svpfn; 1666 unsigned long start_vaddr; 1667 unsigned long end_vaddr; 1668 int ret = 0, copied = 0; 1669 1670 if (!mm || !mmget_not_zero(mm)) 1671 goto out; 1672 1673 ret = -EINVAL; 1674 /* file position must be aligned */ 1675 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1676 goto out_mm; 1677 1678 ret = 0; 1679 if (!count) 1680 goto out_mm; 1681 1682 /* do not disclose physical addresses: attack vector */ 1683 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1684 1685 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1686 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1687 ret = -ENOMEM; 1688 if (!pm.buffer) 1689 goto out_mm; 1690 1691 src = *ppos; 1692 svpfn = src / PM_ENTRY_BYTES; 1693 end_vaddr = mm->task_size; 1694 1695 /* watch out for wraparound */ 1696 start_vaddr = end_vaddr; 1697 if (svpfn <= (ULONG_MAX >> PAGE_SHIFT)) { 1698 unsigned long end; 1699 1700 ret = mmap_read_lock_killable(mm); 1701 if (ret) 1702 goto out_free; 1703 start_vaddr = untagged_addr_remote(mm, svpfn << PAGE_SHIFT); 1704 mmap_read_unlock(mm); 1705 1706 end = start_vaddr + ((count / PM_ENTRY_BYTES) << PAGE_SHIFT); 1707 if (end >= start_vaddr && end < mm->task_size) 1708 end_vaddr = end; 1709 } 1710 1711 /* Ensure the address is inside the task */ 1712 if (start_vaddr > mm->task_size) 1713 start_vaddr = end_vaddr; 1714 1715 ret = 0; 1716 while (count && (start_vaddr < end_vaddr)) { 1717 int len; 1718 unsigned long end; 1719 1720 pm.pos = 0; 1721 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1722 /* overflow ? */ 1723 if (end < start_vaddr || end > end_vaddr) 1724 end = end_vaddr; 1725 ret = mmap_read_lock_killable(mm); 1726 if (ret) 1727 goto out_free; 1728 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1729 mmap_read_unlock(mm); 1730 start_vaddr = end; 1731 1732 len = min(count, PM_ENTRY_BYTES * pm.pos); 1733 if (copy_to_user(buf, pm.buffer, len)) { 1734 ret = -EFAULT; 1735 goto out_free; 1736 } 1737 copied += len; 1738 buf += len; 1739 count -= len; 1740 } 1741 *ppos += copied; 1742 if (!ret || ret == PM_END_OF_BUFFER) 1743 ret = copied; 1744 1745out_free: 1746 kfree(pm.buffer); 1747out_mm: 1748 mmput(mm); 1749out: 1750 return ret; 1751} 1752 1753static int pagemap_open(struct inode *inode, struct file *file) 1754{ 1755 struct mm_struct *mm; 1756 1757 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1758 if (IS_ERR(mm)) 1759 return PTR_ERR(mm); 1760 file->private_data = mm; 1761 return 0; 1762} 1763 1764static int pagemap_release(struct inode *inode, struct file *file) 1765{ 1766 struct mm_struct *mm = file->private_data; 1767 1768 if (mm) 1769 mmdrop(mm); 1770 return 0; 1771} 1772 1773#define PM_SCAN_CATEGORIES (PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN | \ 1774 PAGE_IS_FILE | PAGE_IS_PRESENT | \ 1775 PAGE_IS_SWAPPED | PAGE_IS_PFNZERO | \ 1776 PAGE_IS_HUGE | PAGE_IS_SOFT_DIRTY) 1777#define PM_SCAN_FLAGS (PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC) 1778 1779struct pagemap_scan_private { 1780 struct pm_scan_arg arg; 1781 unsigned long masks_of_interest, cur_vma_category; 1782 struct page_region *vec_buf; 1783 unsigned long vec_buf_len, vec_buf_index, found_pages; 1784 struct page_region __user *vec_out; 1785}; 1786 1787static unsigned long pagemap_page_category(struct pagemap_scan_private *p, 1788 struct vm_area_struct *vma, 1789 unsigned long addr, pte_t pte) 1790{ 1791 unsigned long categories = 0; 1792 1793 if (pte_present(pte)) { 1794 struct page *page; 1795 1796 categories |= PAGE_IS_PRESENT; 1797 if (!pte_uffd_wp(pte)) 1798 categories |= PAGE_IS_WRITTEN; 1799 1800 if (p->masks_of_interest & PAGE_IS_FILE) { 1801 page = vm_normal_page(vma, addr, pte); 1802 if (page && !PageAnon(page)) 1803 categories |= PAGE_IS_FILE; 1804 } 1805 1806 if (is_zero_pfn(pte_pfn(pte))) 1807 categories |= PAGE_IS_PFNZERO; 1808 if (pte_soft_dirty(pte)) 1809 categories |= PAGE_IS_SOFT_DIRTY; 1810 } else if (is_swap_pte(pte)) { 1811 swp_entry_t swp; 1812 1813 categories |= PAGE_IS_SWAPPED; 1814 if (!pte_swp_uffd_wp_any(pte)) 1815 categories |= PAGE_IS_WRITTEN; 1816 1817 if (p->masks_of_interest & PAGE_IS_FILE) { 1818 swp = pte_to_swp_entry(pte); 1819 if (is_pfn_swap_entry(swp) && 1820 !folio_test_anon(pfn_swap_entry_folio(swp))) 1821 categories |= PAGE_IS_FILE; 1822 } 1823 if (pte_swp_soft_dirty(pte)) 1824 categories |= PAGE_IS_SOFT_DIRTY; 1825 } 1826 1827 return categories; 1828} 1829 1830static void make_uffd_wp_pte(struct vm_area_struct *vma, 1831 unsigned long addr, pte_t *pte, pte_t ptent) 1832{ 1833 if (pte_present(ptent)) { 1834 pte_t old_pte; 1835 1836 old_pte = ptep_modify_prot_start(vma, addr, pte); 1837 ptent = pte_mkuffd_wp(old_pte); 1838 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1839 } else if (is_swap_pte(ptent)) { 1840 ptent = pte_swp_mkuffd_wp(ptent); 1841 set_pte_at(vma->vm_mm, addr, pte, ptent); 1842 } else { 1843 set_pte_at(vma->vm_mm, addr, pte, 1844 make_pte_marker(PTE_MARKER_UFFD_WP)); 1845 } 1846} 1847 1848#ifdef CONFIG_TRANSPARENT_HUGEPAGE 1849static unsigned long pagemap_thp_category(struct pagemap_scan_private *p, 1850 struct vm_area_struct *vma, 1851 unsigned long addr, pmd_t pmd) 1852{ 1853 unsigned long categories = PAGE_IS_HUGE; 1854 1855 if (pmd_present(pmd)) { 1856 struct page *page; 1857 1858 categories |= PAGE_IS_PRESENT; 1859 if (!pmd_uffd_wp(pmd)) 1860 categories |= PAGE_IS_WRITTEN; 1861 1862 if (p->masks_of_interest & PAGE_IS_FILE) { 1863 page = vm_normal_page_pmd(vma, addr, pmd); 1864 if (page && !PageAnon(page)) 1865 categories |= PAGE_IS_FILE; 1866 } 1867 1868 if (is_zero_pfn(pmd_pfn(pmd))) 1869 categories |= PAGE_IS_PFNZERO; 1870 if (pmd_soft_dirty(pmd)) 1871 categories |= PAGE_IS_SOFT_DIRTY; 1872 } else if (is_swap_pmd(pmd)) { 1873 swp_entry_t swp; 1874 1875 categories |= PAGE_IS_SWAPPED; 1876 if (!pmd_swp_uffd_wp(pmd)) 1877 categories |= PAGE_IS_WRITTEN; 1878 if (pmd_swp_soft_dirty(pmd)) 1879 categories |= PAGE_IS_SOFT_DIRTY; 1880 1881 if (p->masks_of_interest & PAGE_IS_FILE) { 1882 swp = pmd_to_swp_entry(pmd); 1883 if (is_pfn_swap_entry(swp) && 1884 !folio_test_anon(pfn_swap_entry_folio(swp))) 1885 categories |= PAGE_IS_FILE; 1886 } 1887 } 1888 1889 return categories; 1890} 1891 1892static void make_uffd_wp_pmd(struct vm_area_struct *vma, 1893 unsigned long addr, pmd_t *pmdp) 1894{ 1895 pmd_t old, pmd = *pmdp; 1896 1897 if (pmd_present(pmd)) { 1898 old = pmdp_invalidate_ad(vma, addr, pmdp); 1899 pmd = pmd_mkuffd_wp(old); 1900 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1901 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1902 pmd = pmd_swp_mkuffd_wp(pmd); 1903 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1904 } 1905} 1906#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1907 1908#ifdef CONFIG_HUGETLB_PAGE 1909static unsigned long pagemap_hugetlb_category(pte_t pte) 1910{ 1911 unsigned long categories = PAGE_IS_HUGE; 1912 1913 /* 1914 * According to pagemap_hugetlb_range(), file-backed HugeTLB 1915 * page cannot be swapped. So PAGE_IS_FILE is not checked for 1916 * swapped pages. 1917 */ 1918 if (pte_present(pte)) { 1919 categories |= PAGE_IS_PRESENT; 1920 if (!huge_pte_uffd_wp(pte)) 1921 categories |= PAGE_IS_WRITTEN; 1922 if (!PageAnon(pte_page(pte))) 1923 categories |= PAGE_IS_FILE; 1924 if (is_zero_pfn(pte_pfn(pte))) 1925 categories |= PAGE_IS_PFNZERO; 1926 if (pte_soft_dirty(pte)) 1927 categories |= PAGE_IS_SOFT_DIRTY; 1928 } else if (is_swap_pte(pte)) { 1929 categories |= PAGE_IS_SWAPPED; 1930 if (!pte_swp_uffd_wp_any(pte)) 1931 categories |= PAGE_IS_WRITTEN; 1932 if (pte_swp_soft_dirty(pte)) 1933 categories |= PAGE_IS_SOFT_DIRTY; 1934 } 1935 1936 return categories; 1937} 1938 1939static void make_uffd_wp_huge_pte(struct vm_area_struct *vma, 1940 unsigned long addr, pte_t *ptep, 1941 pte_t ptent) 1942{ 1943 unsigned long psize; 1944 1945 if (is_hugetlb_entry_hwpoisoned(ptent) || is_pte_marker(ptent)) 1946 return; 1947 1948 psize = huge_page_size(hstate_vma(vma)); 1949 1950 if (is_hugetlb_entry_migration(ptent)) 1951 set_huge_pte_at(vma->vm_mm, addr, ptep, 1952 pte_swp_mkuffd_wp(ptent), psize); 1953 else if (!huge_pte_none(ptent)) 1954 huge_ptep_modify_prot_commit(vma, addr, ptep, ptent, 1955 huge_pte_mkuffd_wp(ptent)); 1956 else 1957 set_huge_pte_at(vma->vm_mm, addr, ptep, 1958 make_pte_marker(PTE_MARKER_UFFD_WP), psize); 1959} 1960#endif /* CONFIG_HUGETLB_PAGE */ 1961 1962#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE) 1963static void pagemap_scan_backout_range(struct pagemap_scan_private *p, 1964 unsigned long addr, unsigned long end) 1965{ 1966 struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index]; 1967 1968 if (cur_buf->start != addr) 1969 cur_buf->end = addr; 1970 else 1971 cur_buf->start = cur_buf->end = 0; 1972 1973 p->found_pages -= (end - addr) / PAGE_SIZE; 1974} 1975#endif 1976 1977static bool pagemap_scan_is_interesting_page(unsigned long categories, 1978 const struct pagemap_scan_private *p) 1979{ 1980 categories ^= p->arg.category_inverted; 1981 if ((categories & p->arg.category_mask) != p->arg.category_mask) 1982 return false; 1983 if (p->arg.category_anyof_mask && !(categories & p->arg.category_anyof_mask)) 1984 return false; 1985 1986 return true; 1987} 1988 1989static bool pagemap_scan_is_interesting_vma(unsigned long categories, 1990 const struct pagemap_scan_private *p) 1991{ 1992 unsigned long required = p->arg.category_mask & PAGE_IS_WPALLOWED; 1993 1994 categories ^= p->arg.category_inverted; 1995 if ((categories & required) != required) 1996 return false; 1997 1998 return true; 1999} 2000 2001static int pagemap_scan_test_walk(unsigned long start, unsigned long end, 2002 struct mm_walk *walk) 2003{ 2004 struct pagemap_scan_private *p = walk->private; 2005 struct vm_area_struct *vma = walk->vma; 2006 unsigned long vma_category = 0; 2007 bool wp_allowed = userfaultfd_wp_async(vma) && 2008 userfaultfd_wp_use_markers(vma); 2009 2010 if (!wp_allowed) { 2011 /* User requested explicit failure over wp-async capability */ 2012 if (p->arg.flags & PM_SCAN_CHECK_WPASYNC) 2013 return -EPERM; 2014 /* 2015 * User requires wr-protect, and allows silently skipping 2016 * unsupported vmas. 2017 */ 2018 if (p->arg.flags & PM_SCAN_WP_MATCHING) 2019 return 1; 2020 /* 2021 * Then the request doesn't involve wr-protects at all, 2022 * fall through to the rest checks, and allow vma walk. 2023 */ 2024 } 2025 2026 if (vma->vm_flags & VM_PFNMAP) 2027 return 1; 2028 2029 if (wp_allowed) 2030 vma_category |= PAGE_IS_WPALLOWED; 2031 2032 if (vma->vm_flags & VM_SOFTDIRTY) 2033 vma_category |= PAGE_IS_SOFT_DIRTY; 2034 2035 if (!pagemap_scan_is_interesting_vma(vma_category, p)) 2036 return 1; 2037 2038 p->cur_vma_category = vma_category; 2039 2040 return 0; 2041} 2042 2043static bool pagemap_scan_push_range(unsigned long categories, 2044 struct pagemap_scan_private *p, 2045 unsigned long addr, unsigned long end) 2046{ 2047 struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index]; 2048 2049 /* 2050 * When there is no output buffer provided at all, the sentinel values 2051 * won't match here. There is no other way for `cur_buf->end` to be 2052 * non-zero other than it being non-empty. 2053 */ 2054 if (addr == cur_buf->end && categories == cur_buf->categories) { 2055 cur_buf->end = end; 2056 return true; 2057 } 2058 2059 if (cur_buf->end) { 2060 if (p->vec_buf_index >= p->vec_buf_len - 1) 2061 return false; 2062 2063 cur_buf = &p->vec_buf[++p->vec_buf_index]; 2064 } 2065 2066 cur_buf->start = addr; 2067 cur_buf->end = end; 2068 cur_buf->categories = categories; 2069 2070 return true; 2071} 2072 2073static int pagemap_scan_output(unsigned long categories, 2074 struct pagemap_scan_private *p, 2075 unsigned long addr, unsigned long *end) 2076{ 2077 unsigned long n_pages, total_pages; 2078 int ret = 0; 2079 2080 if (!p->vec_buf) 2081 return 0; 2082 2083 categories &= p->arg.return_mask; 2084 2085 n_pages = (*end - addr) / PAGE_SIZE; 2086 if (check_add_overflow(p->found_pages, n_pages, &total_pages) || 2087 total_pages > p->arg.max_pages) { 2088 size_t n_too_much = total_pages - p->arg.max_pages; 2089 *end -= n_too_much * PAGE_SIZE; 2090 n_pages -= n_too_much; 2091 ret = -ENOSPC; 2092 } 2093 2094 if (!pagemap_scan_push_range(categories, p, addr, *end)) { 2095 *end = addr; 2096 n_pages = 0; 2097 ret = -ENOSPC; 2098 } 2099 2100 p->found_pages += n_pages; 2101 if (ret) 2102 p->arg.walk_end = *end; 2103 2104 return ret; 2105} 2106 2107static int pagemap_scan_thp_entry(pmd_t *pmd, unsigned long start, 2108 unsigned long end, struct mm_walk *walk) 2109{ 2110#ifdef CONFIG_TRANSPARENT_HUGEPAGE 2111 struct pagemap_scan_private *p = walk->private; 2112 struct vm_area_struct *vma = walk->vma; 2113 unsigned long categories; 2114 spinlock_t *ptl; 2115 int ret = 0; 2116 2117 ptl = pmd_trans_huge_lock(pmd, vma); 2118 if (!ptl) 2119 return -ENOENT; 2120 2121 categories = p->cur_vma_category | 2122 pagemap_thp_category(p, vma, start, *pmd); 2123 2124 if (!pagemap_scan_is_interesting_page(categories, p)) 2125 goto out_unlock; 2126 2127 ret = pagemap_scan_output(categories, p, start, &end); 2128 if (start == end) 2129 goto out_unlock; 2130 2131 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2132 goto out_unlock; 2133 if (~categories & PAGE_IS_WRITTEN) 2134 goto out_unlock; 2135 2136 /* 2137 * Break huge page into small pages if the WP operation 2138 * needs to be performed on a portion of the huge page. 2139 */ 2140 if (end != start + HPAGE_SIZE) { 2141 spin_unlock(ptl); 2142 split_huge_pmd(vma, pmd, start); 2143 pagemap_scan_backout_range(p, start, end); 2144 /* Report as if there was no THP */ 2145 return -ENOENT; 2146 } 2147 2148 make_uffd_wp_pmd(vma, start, pmd); 2149 flush_tlb_range(vma, start, end); 2150out_unlock: 2151 spin_unlock(ptl); 2152 return ret; 2153#else /* !CONFIG_TRANSPARENT_HUGEPAGE */ 2154 return -ENOENT; 2155#endif 2156} 2157 2158static int pagemap_scan_pmd_entry(pmd_t *pmd, unsigned long start, 2159 unsigned long end, struct mm_walk *walk) 2160{ 2161 struct pagemap_scan_private *p = walk->private; 2162 struct vm_area_struct *vma = walk->vma; 2163 unsigned long addr, flush_end = 0; 2164 pte_t *pte, *start_pte; 2165 spinlock_t *ptl; 2166 int ret; 2167 2168 arch_enter_lazy_mmu_mode(); 2169 2170 ret = pagemap_scan_thp_entry(pmd, start, end, walk); 2171 if (ret != -ENOENT) { 2172 arch_leave_lazy_mmu_mode(); 2173 return ret; 2174 } 2175 2176 ret = 0; 2177 start_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, start, &ptl); 2178 if (!pte) { 2179 arch_leave_lazy_mmu_mode(); 2180 walk->action = ACTION_AGAIN; 2181 return 0; 2182 } 2183 2184 if ((p->arg.flags & PM_SCAN_WP_MATCHING) && !p->vec_out) { 2185 /* Fast path for performing exclusive WP */ 2186 for (addr = start; addr != end; pte++, addr += PAGE_SIZE) { 2187 pte_t ptent = ptep_get(pte); 2188 2189 if ((pte_present(ptent) && pte_uffd_wp(ptent)) || 2190 pte_swp_uffd_wp_any(ptent)) 2191 continue; 2192 make_uffd_wp_pte(vma, addr, pte, ptent); 2193 if (!flush_end) 2194 start = addr; 2195 flush_end = addr + PAGE_SIZE; 2196 } 2197 goto flush_and_return; 2198 } 2199 2200 if (!p->arg.category_anyof_mask && !p->arg.category_inverted && 2201 p->arg.category_mask == PAGE_IS_WRITTEN && 2202 p->arg.return_mask == PAGE_IS_WRITTEN) { 2203 for (addr = start; addr < end; pte++, addr += PAGE_SIZE) { 2204 unsigned long next = addr + PAGE_SIZE; 2205 pte_t ptent = ptep_get(pte); 2206 2207 if ((pte_present(ptent) && pte_uffd_wp(ptent)) || 2208 pte_swp_uffd_wp_any(ptent)) 2209 continue; 2210 ret = pagemap_scan_output(p->cur_vma_category | PAGE_IS_WRITTEN, 2211 p, addr, &next); 2212 if (next == addr) 2213 break; 2214 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2215 continue; 2216 make_uffd_wp_pte(vma, addr, pte, ptent); 2217 if (!flush_end) 2218 start = addr; 2219 flush_end = next; 2220 } 2221 goto flush_and_return; 2222 } 2223 2224 for (addr = start; addr != end; pte++, addr += PAGE_SIZE) { 2225 pte_t ptent = ptep_get(pte); 2226 unsigned long categories = p->cur_vma_category | 2227 pagemap_page_category(p, vma, addr, ptent); 2228 unsigned long next = addr + PAGE_SIZE; 2229 2230 if (!pagemap_scan_is_interesting_page(categories, p)) 2231 continue; 2232 2233 ret = pagemap_scan_output(categories, p, addr, &next); 2234 if (next == addr) 2235 break; 2236 2237 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2238 continue; 2239 if (~categories & PAGE_IS_WRITTEN) 2240 continue; 2241 2242 make_uffd_wp_pte(vma, addr, pte, ptent); 2243 if (!flush_end) 2244 start = addr; 2245 flush_end = next; 2246 } 2247 2248flush_and_return: 2249 if (flush_end) 2250 flush_tlb_range(vma, start, addr); 2251 2252 pte_unmap_unlock(start_pte, ptl); 2253 arch_leave_lazy_mmu_mode(); 2254 2255 cond_resched(); 2256 return ret; 2257} 2258 2259#ifdef CONFIG_HUGETLB_PAGE 2260static int pagemap_scan_hugetlb_entry(pte_t *ptep, unsigned long hmask, 2261 unsigned long start, unsigned long end, 2262 struct mm_walk *walk) 2263{ 2264 struct pagemap_scan_private *p = walk->private; 2265 struct vm_area_struct *vma = walk->vma; 2266 unsigned long categories; 2267 spinlock_t *ptl; 2268 int ret = 0; 2269 pte_t pte; 2270 2271 if (~p->arg.flags & PM_SCAN_WP_MATCHING) { 2272 /* Go the short route when not write-protecting pages. */ 2273 2274 pte = huge_ptep_get(ptep); 2275 categories = p->cur_vma_category | pagemap_hugetlb_category(pte); 2276 2277 if (!pagemap_scan_is_interesting_page(categories, p)) 2278 return 0; 2279 2280 return pagemap_scan_output(categories, p, start, &end); 2281 } 2282 2283 i_mmap_lock_write(vma->vm_file->f_mapping); 2284 ptl = huge_pte_lock(hstate_vma(vma), vma->vm_mm, ptep); 2285 2286 pte = huge_ptep_get(ptep); 2287 categories = p->cur_vma_category | pagemap_hugetlb_category(pte); 2288 2289 if (!pagemap_scan_is_interesting_page(categories, p)) 2290 goto out_unlock; 2291 2292 ret = pagemap_scan_output(categories, p, start, &end); 2293 if (start == end) 2294 goto out_unlock; 2295 2296 if (~categories & PAGE_IS_WRITTEN) 2297 goto out_unlock; 2298 2299 if (end != start + HPAGE_SIZE) { 2300 /* Partial HugeTLB page WP isn't possible. */ 2301 pagemap_scan_backout_range(p, start, end); 2302 p->arg.walk_end = start; 2303 ret = 0; 2304 goto out_unlock; 2305 } 2306 2307 make_uffd_wp_huge_pte(vma, start, ptep, pte); 2308 flush_hugetlb_tlb_range(vma, start, end); 2309 2310out_unlock: 2311 spin_unlock(ptl); 2312 i_mmap_unlock_write(vma->vm_file->f_mapping); 2313 2314 return ret; 2315} 2316#else 2317#define pagemap_scan_hugetlb_entry NULL 2318#endif 2319 2320static int pagemap_scan_pte_hole(unsigned long addr, unsigned long end, 2321 int depth, struct mm_walk *walk) 2322{ 2323 struct pagemap_scan_private *p = walk->private; 2324 struct vm_area_struct *vma = walk->vma; 2325 int ret, err; 2326 2327 if (!vma || !pagemap_scan_is_interesting_page(p->cur_vma_category, p)) 2328 return 0; 2329 2330 ret = pagemap_scan_output(p->cur_vma_category, p, addr, &end); 2331 if (addr == end) 2332 return ret; 2333 2334 if (~p->arg.flags & PM_SCAN_WP_MATCHING) 2335 return ret; 2336 2337 err = uffd_wp_range(vma, addr, end - addr, true); 2338 if (err < 0) 2339 ret = err; 2340 2341 return ret; 2342} 2343 2344static const struct mm_walk_ops pagemap_scan_ops = { 2345 .test_walk = pagemap_scan_test_walk, 2346 .pmd_entry = pagemap_scan_pmd_entry, 2347 .pte_hole = pagemap_scan_pte_hole, 2348 .hugetlb_entry = pagemap_scan_hugetlb_entry, 2349}; 2350 2351static int pagemap_scan_get_args(struct pm_scan_arg *arg, 2352 unsigned long uarg) 2353{ 2354 if (copy_from_user(arg, (void __user *)uarg, sizeof(*arg))) 2355 return -EFAULT; 2356 2357 if (arg->size != sizeof(struct pm_scan_arg)) 2358 return -EINVAL; 2359 2360 /* Validate requested features */ 2361 if (arg->flags & ~PM_SCAN_FLAGS) 2362 return -EINVAL; 2363 if ((arg->category_inverted | arg->category_mask | 2364 arg->category_anyof_mask | arg->return_mask) & ~PM_SCAN_CATEGORIES) 2365 return -EINVAL; 2366 2367 arg->start = untagged_addr((unsigned long)arg->start); 2368 arg->end = untagged_addr((unsigned long)arg->end); 2369 arg->vec = untagged_addr((unsigned long)arg->vec); 2370 2371 /* Validate memory pointers */ 2372 if (!IS_ALIGNED(arg->start, PAGE_SIZE)) 2373 return -EINVAL; 2374 if (!access_ok((void __user *)(long)arg->start, arg->end - arg->start)) 2375 return -EFAULT; 2376 if (!arg->vec && arg->vec_len) 2377 return -EINVAL; 2378 if (arg->vec && !access_ok((void __user *)(long)arg->vec, 2379 arg->vec_len * sizeof(struct page_region))) 2380 return -EFAULT; 2381 2382 /* Fixup default values */ 2383 arg->end = ALIGN(arg->end, PAGE_SIZE); 2384 arg->walk_end = 0; 2385 if (!arg->max_pages) 2386 arg->max_pages = ULONG_MAX; 2387 2388 return 0; 2389} 2390 2391static int pagemap_scan_writeback_args(struct pm_scan_arg *arg, 2392 unsigned long uargl) 2393{ 2394 struct pm_scan_arg __user *uarg = (void __user *)uargl; 2395 2396 if (copy_to_user(&uarg->walk_end, &arg->walk_end, sizeof(arg->walk_end))) 2397 return -EFAULT; 2398 2399 return 0; 2400} 2401 2402static int pagemap_scan_init_bounce_buffer(struct pagemap_scan_private *p) 2403{ 2404 if (!p->arg.vec_len) 2405 return 0; 2406 2407 p->vec_buf_len = min_t(size_t, PAGEMAP_WALK_SIZE >> PAGE_SHIFT, 2408 p->arg.vec_len); 2409 p->vec_buf = kmalloc_array(p->vec_buf_len, sizeof(*p->vec_buf), 2410 GFP_KERNEL); 2411 if (!p->vec_buf) 2412 return -ENOMEM; 2413 2414 p->vec_buf->start = p->vec_buf->end = 0; 2415 p->vec_out = (struct page_region __user *)(long)p->arg.vec; 2416 2417 return 0; 2418} 2419 2420static long pagemap_scan_flush_buffer(struct pagemap_scan_private *p) 2421{ 2422 const struct page_region *buf = p->vec_buf; 2423 long n = p->vec_buf_index; 2424 2425 if (!p->vec_buf) 2426 return 0; 2427 2428 if (buf[n].end != buf[n].start) 2429 n++; 2430 2431 if (!n) 2432 return 0; 2433 2434 if (copy_to_user(p->vec_out, buf, n * sizeof(*buf))) 2435 return -EFAULT; 2436 2437 p->arg.vec_len -= n; 2438 p->vec_out += n; 2439 2440 p->vec_buf_index = 0; 2441 p->vec_buf_len = min_t(size_t, p->vec_buf_len, p->arg.vec_len); 2442 p->vec_buf->start = p->vec_buf->end = 0; 2443 2444 return n; 2445} 2446 2447static long do_pagemap_scan(struct mm_struct *mm, unsigned long uarg) 2448{ 2449 struct pagemap_scan_private p = {0}; 2450 unsigned long walk_start; 2451 size_t n_ranges_out = 0; 2452 int ret; 2453 2454 ret = pagemap_scan_get_args(&p.arg, uarg); 2455 if (ret) 2456 return ret; 2457 2458 p.masks_of_interest = p.arg.category_mask | p.arg.category_anyof_mask | 2459 p.arg.return_mask; 2460 ret = pagemap_scan_init_bounce_buffer(&p); 2461 if (ret) 2462 return ret; 2463 2464 for (walk_start = p.arg.start; walk_start < p.arg.end; 2465 walk_start = p.arg.walk_end) { 2466 struct mmu_notifier_range range; 2467 long n_out; 2468 2469 if (fatal_signal_pending(current)) { 2470 ret = -EINTR; 2471 break; 2472 } 2473 2474 ret = mmap_read_lock_killable(mm); 2475 if (ret) 2476 break; 2477 2478 /* Protection change for the range is going to happen. */ 2479 if (p.arg.flags & PM_SCAN_WP_MATCHING) { 2480 mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, 0, 2481 mm, walk_start, p.arg.end); 2482 mmu_notifier_invalidate_range_start(&range); 2483 } 2484 2485 ret = walk_page_range(mm, walk_start, p.arg.end, 2486 &pagemap_scan_ops, &p); 2487 2488 if (p.arg.flags & PM_SCAN_WP_MATCHING) 2489 mmu_notifier_invalidate_range_end(&range); 2490 2491 mmap_read_unlock(mm); 2492 2493 n_out = pagemap_scan_flush_buffer(&p); 2494 if (n_out < 0) 2495 ret = n_out; 2496 else 2497 n_ranges_out += n_out; 2498 2499 if (ret != -ENOSPC) 2500 break; 2501 2502 if (p.arg.vec_len == 0 || p.found_pages == p.arg.max_pages) 2503 break; 2504 } 2505 2506 /* ENOSPC signifies early stop (buffer full) from the walk. */ 2507 if (!ret || ret == -ENOSPC) 2508 ret = n_ranges_out; 2509 2510 /* The walk_end isn't set when ret is zero */ 2511 if (!p.arg.walk_end) 2512 p.arg.walk_end = p.arg.end; 2513 if (pagemap_scan_writeback_args(&p.arg, uarg)) 2514 ret = -EFAULT; 2515 2516 kfree(p.vec_buf); 2517 return ret; 2518} 2519 2520static long do_pagemap_cmd(struct file *file, unsigned int cmd, 2521 unsigned long arg) 2522{ 2523 struct mm_struct *mm = file->private_data; 2524 2525 switch (cmd) { 2526 case PAGEMAP_SCAN: 2527 return do_pagemap_scan(mm, arg); 2528 2529 default: 2530 return -EINVAL; 2531 } 2532} 2533 2534const struct file_operations proc_pagemap_operations = { 2535 .llseek = mem_lseek, /* borrow this */ 2536 .read = pagemap_read, 2537 .open = pagemap_open, 2538 .release = pagemap_release, 2539 .unlocked_ioctl = do_pagemap_cmd, 2540 .compat_ioctl = do_pagemap_cmd, 2541}; 2542#endif /* CONFIG_PROC_PAGE_MONITOR */ 2543 2544#ifdef CONFIG_NUMA 2545 2546struct numa_maps { 2547 unsigned long pages; 2548 unsigned long anon; 2549 unsigned long active; 2550 unsigned long writeback; 2551 unsigned long mapcount_max; 2552 unsigned long dirty; 2553 unsigned long swapcache; 2554 unsigned long node[MAX_NUMNODES]; 2555}; 2556 2557struct numa_maps_private { 2558 struct proc_maps_private proc_maps; 2559 struct numa_maps md; 2560}; 2561 2562static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 2563 unsigned long nr_pages) 2564{ 2565 struct folio *folio = page_folio(page); 2566 int count = page_mapcount(page); 2567 2568 md->pages += nr_pages; 2569 if (pte_dirty || folio_test_dirty(folio)) 2570 md->dirty += nr_pages; 2571 2572 if (folio_test_swapcache(folio)) 2573 md->swapcache += nr_pages; 2574 2575 if (folio_test_active(folio) || folio_test_unevictable(folio)) 2576 md->active += nr_pages; 2577 2578 if (folio_test_writeback(folio)) 2579 md->writeback += nr_pages; 2580 2581 if (folio_test_anon(folio)) 2582 md->anon += nr_pages; 2583 2584 if (count > md->mapcount_max) 2585 md->mapcount_max = count; 2586 2587 md->node[folio_nid(folio)] += nr_pages; 2588} 2589 2590static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 2591 unsigned long addr) 2592{ 2593 struct page *page; 2594 int nid; 2595 2596 if (!pte_present(pte)) 2597 return NULL; 2598 2599 page = vm_normal_page(vma, addr, pte); 2600 if (!page || is_zone_device_page(page)) 2601 return NULL; 2602 2603 if (PageReserved(page)) 2604 return NULL; 2605 2606 nid = page_to_nid(page); 2607 if (!node_isset(nid, node_states[N_MEMORY])) 2608 return NULL; 2609 2610 return page; 2611} 2612 2613#ifdef CONFIG_TRANSPARENT_HUGEPAGE 2614static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 2615 struct vm_area_struct *vma, 2616 unsigned long addr) 2617{ 2618 struct page *page; 2619 int nid; 2620 2621 if (!pmd_present(pmd)) 2622 return NULL; 2623 2624 page = vm_normal_page_pmd(vma, addr, pmd); 2625 if (!page) 2626 return NULL; 2627 2628 if (PageReserved(page)) 2629 return NULL; 2630 2631 nid = page_to_nid(page); 2632 if (!node_isset(nid, node_states[N_MEMORY])) 2633 return NULL; 2634 2635 return page; 2636} 2637#endif 2638 2639static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 2640 unsigned long end, struct mm_walk *walk) 2641{ 2642 struct numa_maps *md = walk->private; 2643 struct vm_area_struct *vma = walk->vma; 2644 spinlock_t *ptl; 2645 pte_t *orig_pte; 2646 pte_t *pte; 2647 2648#ifdef CONFIG_TRANSPARENT_HUGEPAGE 2649 ptl = pmd_trans_huge_lock(pmd, vma); 2650 if (ptl) { 2651 struct page *page; 2652 2653 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 2654 if (page) 2655 gather_stats(page, md, pmd_dirty(*pmd), 2656 HPAGE_PMD_SIZE/PAGE_SIZE); 2657 spin_unlock(ptl); 2658 return 0; 2659 } 2660#endif 2661 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 2662 if (!pte) { 2663 walk->action = ACTION_AGAIN; 2664 return 0; 2665 } 2666 do { 2667 pte_t ptent = ptep_get(pte); 2668 struct page *page = can_gather_numa_stats(ptent, vma, addr); 2669 if (!page) 2670 continue; 2671 gather_stats(page, md, pte_dirty(ptent), 1); 2672 2673 } while (pte++, addr += PAGE_SIZE, addr != end); 2674 pte_unmap_unlock(orig_pte, ptl); 2675 cond_resched(); 2676 return 0; 2677} 2678#ifdef CONFIG_HUGETLB_PAGE 2679static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 2680 unsigned long addr, unsigned long end, struct mm_walk *walk) 2681{ 2682 pte_t huge_pte = huge_ptep_get(pte); 2683 struct numa_maps *md; 2684 struct page *page; 2685 2686 if (!pte_present(huge_pte)) 2687 return 0; 2688 2689 page = pte_page(huge_pte); 2690 2691 md = walk->private; 2692 gather_stats(page, md, pte_dirty(huge_pte), 1); 2693 return 0; 2694} 2695 2696#else 2697static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 2698 unsigned long addr, unsigned long end, struct mm_walk *walk) 2699{ 2700 return 0; 2701} 2702#endif 2703 2704static const struct mm_walk_ops show_numa_ops = { 2705 .hugetlb_entry = gather_hugetlb_stats, 2706 .pmd_entry = gather_pte_stats, 2707 .walk_lock = PGWALK_RDLOCK, 2708}; 2709 2710/* 2711 * Display pages allocated per node and memory policy via /proc. 2712 */ 2713static int show_numa_map(struct seq_file *m, void *v) 2714{ 2715 struct numa_maps_private *numa_priv = m->private; 2716 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 2717 struct vm_area_struct *vma = v; 2718 struct numa_maps *md = &numa_priv->md; 2719 struct file *file = vma->vm_file; 2720 struct mm_struct *mm = vma->vm_mm; 2721 char buffer[64]; 2722 struct mempolicy *pol; 2723 pgoff_t ilx; 2724 int nid; 2725 2726 if (!mm) 2727 return 0; 2728 2729 /* Ensure we start with an empty set of numa_maps statistics. */ 2730 memset(md, 0, sizeof(*md)); 2731 2732 pol = __get_vma_policy(vma, vma->vm_start, &ilx); 2733 if (pol) { 2734 mpol_to_str(buffer, sizeof(buffer), pol); 2735 mpol_cond_put(pol); 2736 } else { 2737 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 2738 } 2739 2740 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 2741 2742 if (file) { 2743 seq_puts(m, " file="); 2744 seq_path(m, file_user_path(file), "\n\t= "); 2745 } else if (vma_is_initial_heap(vma)) { 2746 seq_puts(m, " heap"); 2747 } else if (vma_is_initial_stack(vma)) { 2748 seq_puts(m, " stack"); 2749 } 2750 2751 if (is_vm_hugetlb_page(vma)) 2752 seq_puts(m, " huge"); 2753 2754 /* mmap_lock is held by m_start */ 2755 walk_page_vma(vma, &show_numa_ops, md); 2756 2757 if (!md->pages) 2758 goto out; 2759 2760 if (md->anon) 2761 seq_printf(m, " anon=%lu", md->anon); 2762 2763 if (md->dirty) 2764 seq_printf(m, " dirty=%lu", md->dirty); 2765 2766 if (md->pages != md->anon && md->pages != md->dirty) 2767 seq_printf(m, " mapped=%lu", md->pages); 2768 2769 if (md->mapcount_max > 1) 2770 seq_printf(m, " mapmax=%lu", md->mapcount_max); 2771 2772 if (md->swapcache) 2773 seq_printf(m, " swapcache=%lu", md->swapcache); 2774 2775 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 2776 seq_printf(m, " active=%lu", md->active); 2777 2778 if (md->writeback) 2779 seq_printf(m, " writeback=%lu", md->writeback); 2780 2781 for_each_node_state(nid, N_MEMORY) 2782 if (md->node[nid]) 2783 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 2784 2785 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 2786out: 2787 seq_putc(m, '\n'); 2788 return 0; 2789} 2790 2791static const struct seq_operations proc_pid_numa_maps_op = { 2792 .start = m_start, 2793 .next = m_next, 2794 .stop = m_stop, 2795 .show = show_numa_map, 2796}; 2797 2798static int pid_numa_maps_open(struct inode *inode, struct file *file) 2799{ 2800 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 2801 sizeof(struct numa_maps_private)); 2802} 2803 2804const struct file_operations proc_pid_numa_maps_operations = { 2805 .open = pid_numa_maps_open, 2806 .read = seq_read, 2807 .llseek = seq_lseek, 2808 .release = proc_map_release, 2809}; 2810 2811#endif /* CONFIG_NUMA */ 2812