1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/pagewalk.h> 3 #include <linux/vmacache.h> 4 #include <linux/mm_inline.h> 5 #include <linux/hugetlb.h> 6 #include <linux/huge_mm.h> 7 #include <linux/mount.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 24 #include <asm/elf.h> 25 #include <asm/tlb.h> 26 #include <asm/tlbflush.h> 27 #include "internal.h" 28 29 #define SEQ_PUT_DEC(str, val) \ 30 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8) 31 void task_mem(struct seq_file *m, struct mm_struct *mm) 32 { 33 unsigned long text, lib, swap, anon, file, shmem; 34 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 35 36 anon = get_mm_counter(mm, MM_ANONPAGES); 37 file = get_mm_counter(mm, MM_FILEPAGES); 38 shmem = get_mm_counter(mm, MM_SHMEMPAGES); 39 40 /* 41 * Note: to minimize their overhead, mm maintains hiwater_vm and 42 * hiwater_rss only when about to *lower* total_vm or rss. Any 43 * collector of these hiwater stats must therefore get total_vm 44 * and rss too, which will usually be the higher. Barriers? not 45 * worth the effort, such snapshots can always be inconsistent. 46 */ 47 hiwater_vm = total_vm = mm->total_vm; 48 if (hiwater_vm < mm->hiwater_vm) 49 hiwater_vm = mm->hiwater_vm; 50 hiwater_rss = total_rss = anon + file + shmem; 51 if (hiwater_rss < mm->hiwater_rss) 52 hiwater_rss = mm->hiwater_rss; 53 54 /* split executable areas between text and lib */ 55 text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK); 56 text = min(text, mm->exec_vm << PAGE_SHIFT); 57 lib = (mm->exec_vm << PAGE_SHIFT) - text; 58 59 swap = get_mm_counter(mm, MM_SWAPENTS); 60 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm); 61 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm); 62 SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm); 63 SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm)); 64 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss); 65 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss); 66 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon); 67 SEQ_PUT_DEC(" kB\nRssFile:\t", file); 68 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem); 69 SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm); 70 SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm); 71 seq_put_decimal_ull_width(m, 72 " kB\nVmExe:\t", text >> 10, 8); 73 seq_put_decimal_ull_width(m, 74 " kB\nVmLib:\t", lib >> 10, 8); 75 seq_put_decimal_ull_width(m, 76 " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8); 77 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap); 78 seq_puts(m, " kB\n"); 79 hugetlb_report_usage(m, mm); 80 } 81 #undef SEQ_PUT_DEC 82 83 unsigned long task_vsize(struct mm_struct *mm) 84 { 85 return PAGE_SIZE * mm->total_vm; 86 } 87 88 unsigned long task_statm(struct mm_struct *mm, 89 unsigned long *shared, unsigned long *text, 90 unsigned long *data, unsigned long *resident) 91 { 92 *shared = get_mm_counter(mm, MM_FILEPAGES) + 93 get_mm_counter(mm, MM_SHMEMPAGES); 94 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 95 >> PAGE_SHIFT; 96 *data = mm->data_vm + mm->stack_vm; 97 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 98 return mm->total_vm; 99 } 100 101 #ifdef CONFIG_NUMA 102 /* 103 * Save get_task_policy() for show_numa_map(). 104 */ 105 static void hold_task_mempolicy(struct proc_maps_private *priv) 106 { 107 struct task_struct *task = priv->task; 108 109 task_lock(task); 110 priv->task_mempolicy = get_task_policy(task); 111 mpol_get(priv->task_mempolicy); 112 task_unlock(task); 113 } 114 static void release_task_mempolicy(struct proc_maps_private *priv) 115 { 116 mpol_put(priv->task_mempolicy); 117 } 118 #else 119 static void hold_task_mempolicy(struct proc_maps_private *priv) 120 { 121 } 122 static void release_task_mempolicy(struct proc_maps_private *priv) 123 { 124 } 125 #endif 126 127 static void *m_start(struct seq_file *m, loff_t *ppos) 128 { 129 struct proc_maps_private *priv = m->private; 130 unsigned long last_addr = *ppos; 131 struct mm_struct *mm; 132 struct vm_area_struct *vma; 133 134 /* See m_next(). Zero at the start or after lseek. */ 135 if (last_addr == -1UL) 136 return NULL; 137 138 priv->task = get_proc_task(priv->inode); 139 if (!priv->task) 140 return ERR_PTR(-ESRCH); 141 142 mm = priv->mm; 143 if (!mm || !mmget_not_zero(mm)) { 144 put_task_struct(priv->task); 145 priv->task = NULL; 146 return NULL; 147 } 148 149 if (mmap_read_lock_killable(mm)) { 150 mmput(mm); 151 put_task_struct(priv->task); 152 priv->task = NULL; 153 return ERR_PTR(-EINTR); 154 } 155 156 hold_task_mempolicy(priv); 157 priv->tail_vma = get_gate_vma(mm); 158 159 vma = find_vma(mm, last_addr); 160 if (vma) 161 return vma; 162 163 return priv->tail_vma; 164 } 165 166 static void *m_next(struct seq_file *m, void *v, loff_t *ppos) 167 { 168 struct proc_maps_private *priv = m->private; 169 struct vm_area_struct *next, *vma = v; 170 171 if (vma == priv->tail_vma) 172 next = NULL; 173 else if (vma->vm_next) 174 next = vma->vm_next; 175 else 176 next = priv->tail_vma; 177 178 *ppos = next ? next->vm_start : -1UL; 179 180 return next; 181 } 182 183 static void m_stop(struct seq_file *m, void *v) 184 { 185 struct proc_maps_private *priv = m->private; 186 struct mm_struct *mm = priv->mm; 187 188 if (!priv->task) 189 return; 190 191 release_task_mempolicy(priv); 192 mmap_read_unlock(mm); 193 mmput(mm); 194 put_task_struct(priv->task); 195 priv->task = NULL; 196 } 197 198 static int proc_maps_open(struct inode *inode, struct file *file, 199 const struct seq_operations *ops, int psize) 200 { 201 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 202 203 if (!priv) 204 return -ENOMEM; 205 206 priv->inode = inode; 207 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 208 if (IS_ERR(priv->mm)) { 209 int err = PTR_ERR(priv->mm); 210 211 seq_release_private(inode, file); 212 return err; 213 } 214 215 return 0; 216 } 217 218 static int proc_map_release(struct inode *inode, struct file *file) 219 { 220 struct seq_file *seq = file->private_data; 221 struct proc_maps_private *priv = seq->private; 222 223 if (priv->mm) 224 mmdrop(priv->mm); 225 226 return seq_release_private(inode, file); 227 } 228 229 static int do_maps_open(struct inode *inode, struct file *file, 230 const struct seq_operations *ops) 231 { 232 return proc_maps_open(inode, file, ops, 233 sizeof(struct proc_maps_private)); 234 } 235 236 /* 237 * Indicate if the VMA is a stack for the given task; for 238 * /proc/PID/maps that is the stack of the main task. 239 */ 240 static int is_stack(struct vm_area_struct *vma) 241 { 242 /* 243 * We make no effort to guess what a given thread considers to be 244 * its "stack". It's not even well-defined for programs written 245 * languages like Go. 246 */ 247 return vma->vm_start <= vma->vm_mm->start_stack && 248 vma->vm_end >= vma->vm_mm->start_stack; 249 } 250 251 static void show_vma_header_prefix(struct seq_file *m, 252 unsigned long start, unsigned long end, 253 vm_flags_t flags, unsigned long long pgoff, 254 dev_t dev, unsigned long ino) 255 { 256 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 257 seq_put_hex_ll(m, NULL, start, 8); 258 seq_put_hex_ll(m, "-", end, 8); 259 seq_putc(m, ' '); 260 seq_putc(m, flags & VM_READ ? 'r' : '-'); 261 seq_putc(m, flags & VM_WRITE ? 'w' : '-'); 262 seq_putc(m, flags & VM_EXEC ? 'x' : '-'); 263 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p'); 264 seq_put_hex_ll(m, " ", pgoff, 8); 265 seq_put_hex_ll(m, " ", MAJOR(dev), 2); 266 seq_put_hex_ll(m, ":", MINOR(dev), 2); 267 seq_put_decimal_ull(m, " ", ino); 268 seq_putc(m, ' '); 269 } 270 271 static void 272 show_map_vma(struct seq_file *m, struct vm_area_struct *vma) 273 { 274 struct mm_struct *mm = vma->vm_mm; 275 struct file *file = vma->vm_file; 276 vm_flags_t flags = vma->vm_flags; 277 unsigned long ino = 0; 278 unsigned long long pgoff = 0; 279 unsigned long start, end; 280 dev_t dev = 0; 281 const char *name = NULL; 282 283 if (file) { 284 struct inode *inode = file_inode(vma->vm_file); 285 dev = inode->i_sb->s_dev; 286 ino = inode->i_ino; 287 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 288 } 289 290 start = vma->vm_start; 291 end = vma->vm_end; 292 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 293 294 /* 295 * Print the dentry name for named mappings, and a 296 * special [heap] marker for the heap: 297 */ 298 if (file) { 299 seq_pad(m, ' '); 300 seq_file_path(m, file, "\n"); 301 goto done; 302 } 303 304 if (vma->vm_ops && vma->vm_ops->name) { 305 name = vma->vm_ops->name(vma); 306 if (name) 307 goto done; 308 } 309 310 name = arch_vma_name(vma); 311 if (!name) { 312 struct anon_vma_name *anon_name; 313 314 if (!mm) { 315 name = "[vdso]"; 316 goto done; 317 } 318 319 if (vma->vm_start <= mm->brk && 320 vma->vm_end >= mm->start_brk) { 321 name = "[heap]"; 322 goto done; 323 } 324 325 if (is_stack(vma)) { 326 name = "[stack]"; 327 goto done; 328 } 329 330 anon_name = anon_vma_name(vma); 331 if (anon_name) { 332 seq_pad(m, ' '); 333 seq_printf(m, "[anon:%s]", anon_name->name); 334 } 335 } 336 337 done: 338 if (name) { 339 seq_pad(m, ' '); 340 seq_puts(m, name); 341 } 342 seq_putc(m, '\n'); 343 } 344 345 static int show_map(struct seq_file *m, void *v) 346 { 347 show_map_vma(m, v); 348 return 0; 349 } 350 351 static const struct seq_operations proc_pid_maps_op = { 352 .start = m_start, 353 .next = m_next, 354 .stop = m_stop, 355 .show = show_map 356 }; 357 358 static int pid_maps_open(struct inode *inode, struct file *file) 359 { 360 return do_maps_open(inode, file, &proc_pid_maps_op); 361 } 362 363 const struct file_operations proc_pid_maps_operations = { 364 .open = pid_maps_open, 365 .read = seq_read, 366 .llseek = seq_lseek, 367 .release = proc_map_release, 368 }; 369 370 /* 371 * Proportional Set Size(PSS): my share of RSS. 372 * 373 * PSS of a process is the count of pages it has in memory, where each 374 * page is divided by the number of processes sharing it. So if a 375 * process has 1000 pages all to itself, and 1000 shared with one other 376 * process, its PSS will be 1500. 377 * 378 * To keep (accumulated) division errors low, we adopt a 64bit 379 * fixed-point pss counter to minimize division errors. So (pss >> 380 * PSS_SHIFT) would be the real byte count. 381 * 382 * A shift of 12 before division means (assuming 4K page size): 383 * - 1M 3-user-pages add up to 8KB errors; 384 * - supports mapcount up to 2^24, or 16M; 385 * - supports PSS up to 2^52 bytes, or 4PB. 386 */ 387 #define PSS_SHIFT 12 388 389 #ifdef CONFIG_PROC_PAGE_MONITOR 390 struct mem_size_stats { 391 unsigned long resident; 392 unsigned long shared_clean; 393 unsigned long shared_dirty; 394 unsigned long private_clean; 395 unsigned long private_dirty; 396 unsigned long referenced; 397 unsigned long anonymous; 398 unsigned long lazyfree; 399 unsigned long anonymous_thp; 400 unsigned long shmem_thp; 401 unsigned long file_thp; 402 unsigned long swap; 403 unsigned long shared_hugetlb; 404 unsigned long private_hugetlb; 405 u64 pss; 406 u64 pss_anon; 407 u64 pss_file; 408 u64 pss_shmem; 409 u64 pss_dirty; 410 u64 pss_locked; 411 u64 swap_pss; 412 }; 413 414 static void smaps_page_accumulate(struct mem_size_stats *mss, 415 struct page *page, unsigned long size, unsigned long pss, 416 bool dirty, bool locked, bool private) 417 { 418 mss->pss += pss; 419 420 if (PageAnon(page)) 421 mss->pss_anon += pss; 422 else if (PageSwapBacked(page)) 423 mss->pss_shmem += pss; 424 else 425 mss->pss_file += pss; 426 427 if (locked) 428 mss->pss_locked += pss; 429 430 if (dirty || PageDirty(page)) { 431 mss->pss_dirty += pss; 432 if (private) 433 mss->private_dirty += size; 434 else 435 mss->shared_dirty += size; 436 } else { 437 if (private) 438 mss->private_clean += size; 439 else 440 mss->shared_clean += size; 441 } 442 } 443 444 static void smaps_account(struct mem_size_stats *mss, struct page *page, 445 bool compound, bool young, bool dirty, bool locked, 446 bool migration) 447 { 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 (PageAnon(page)) { 456 mss->anonymous += size; 457 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 458 mss->lazyfree += size; 459 } 460 461 mss->resident += size; 462 /* Accumulate the size in pages that have been accessed. */ 463 if (young || page_is_young(page) || PageReferenced(page)) 464 mss->referenced += size; 465 466 /* 467 * Then accumulate quantities that may depend on sharing, or that may 468 * differ page-by-page. 469 * 470 * page_count(page) == 1 guarantees the page is mapped exactly once. 471 * If any subpage of the compound page mapped with PTE it would elevate 472 * page_count(). 473 * 474 * The page_mapcount() is called to get a snapshot of the mapcount. 475 * Without holding the page lock this snapshot can be slightly wrong as 476 * we cannot always read the mapcount atomically. It is not safe to 477 * call page_mapcount() even with PTL held if the page is not mapped, 478 * especially for migration entries. Treat regular migration entries 479 * as mapcount == 1. 480 */ 481 if ((page_count(page) == 1) || migration) { 482 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, 483 locked, true); 484 return; 485 } 486 for (i = 0; i < nr; i++, page++) { 487 int mapcount = page_mapcount(page); 488 unsigned long pss = PAGE_SIZE << PSS_SHIFT; 489 if (mapcount >= 2) 490 pss /= mapcount; 491 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked, 492 mapcount < 2); 493 } 494 } 495 496 #ifdef CONFIG_SHMEM 497 static int smaps_pte_hole(unsigned long addr, unsigned long end, 498 __always_unused int depth, struct mm_walk *walk) 499 { 500 struct mem_size_stats *mss = walk->private; 501 struct vm_area_struct *vma = walk->vma; 502 503 mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping, 504 linear_page_index(vma, addr), 505 linear_page_index(vma, end)); 506 507 return 0; 508 } 509 #else 510 #define smaps_pte_hole NULL 511 #endif /* CONFIG_SHMEM */ 512 513 static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk) 514 { 515 #ifdef CONFIG_SHMEM 516 if (walk->ops->pte_hole) { 517 /* depth is not used */ 518 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk); 519 } 520 #endif 521 } 522 523 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 524 struct mm_walk *walk) 525 { 526 struct mem_size_stats *mss = walk->private; 527 struct vm_area_struct *vma = walk->vma; 528 bool locked = !!(vma->vm_flags & VM_LOCKED); 529 struct page *page = NULL; 530 bool migration = false, young = false, dirty = false; 531 532 if (pte_present(*pte)) { 533 page = vm_normal_page(vma, addr, *pte); 534 young = pte_young(*pte); 535 dirty = pte_dirty(*pte); 536 } else if (is_swap_pte(*pte)) { 537 swp_entry_t swpent = pte_to_swp_entry(*pte); 538 539 if (!non_swap_entry(swpent)) { 540 int mapcount; 541 542 mss->swap += PAGE_SIZE; 543 mapcount = swp_swapcount(swpent); 544 if (mapcount >= 2) { 545 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 546 547 do_div(pss_delta, mapcount); 548 mss->swap_pss += pss_delta; 549 } else { 550 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 551 } 552 } else if (is_pfn_swap_entry(swpent)) { 553 if (is_migration_entry(swpent)) 554 migration = true; 555 page = pfn_swap_entry_to_page(swpent); 556 } 557 } else { 558 smaps_pte_hole_lookup(addr, walk); 559 return; 560 } 561 562 if (!page) 563 return; 564 565 smaps_account(mss, page, false, young, dirty, locked, migration); 566 } 567 568 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 569 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 570 struct mm_walk *walk) 571 { 572 struct mem_size_stats *mss = walk->private; 573 struct vm_area_struct *vma = walk->vma; 574 bool locked = !!(vma->vm_flags & VM_LOCKED); 575 struct page *page = NULL; 576 bool migration = false; 577 578 if (pmd_present(*pmd)) { 579 /* FOLL_DUMP will return -EFAULT on huge zero page */ 580 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 581 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { 582 swp_entry_t entry = pmd_to_swp_entry(*pmd); 583 584 if (is_migration_entry(entry)) { 585 migration = true; 586 page = pfn_swap_entry_to_page(entry); 587 } 588 } 589 if (IS_ERR_OR_NULL(page)) 590 return; 591 if (PageAnon(page)) 592 mss->anonymous_thp += HPAGE_PMD_SIZE; 593 else if (PageSwapBacked(page)) 594 mss->shmem_thp += HPAGE_PMD_SIZE; 595 else if (is_zone_device_page(page)) 596 /* pass */; 597 else 598 mss->file_thp += HPAGE_PMD_SIZE; 599 600 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), 601 locked, migration); 602 } 603 #else 604 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 605 struct mm_walk *walk) 606 { 607 } 608 #endif 609 610 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 611 struct mm_walk *walk) 612 { 613 struct vm_area_struct *vma = walk->vma; 614 pte_t *pte; 615 spinlock_t *ptl; 616 617 ptl = pmd_trans_huge_lock(pmd, vma); 618 if (ptl) { 619 smaps_pmd_entry(pmd, addr, walk); 620 spin_unlock(ptl); 621 goto out; 622 } 623 624 if (pmd_trans_unstable(pmd)) 625 goto out; 626 /* 627 * The mmap_lock held all the way back in m_start() is what 628 * keeps khugepaged out of here and from collapsing things 629 * in here. 630 */ 631 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 632 for (; addr != end; pte++, addr += PAGE_SIZE) 633 smaps_pte_entry(pte, addr, walk); 634 pte_unmap_unlock(pte - 1, ptl); 635 out: 636 cond_resched(); 637 return 0; 638 } 639 640 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 641 { 642 /* 643 * Don't forget to update Documentation/ on changes. 644 */ 645 static const char mnemonics[BITS_PER_LONG][2] = { 646 /* 647 * In case if we meet a flag we don't know about. 648 */ 649 [0 ... (BITS_PER_LONG-1)] = "??", 650 651 [ilog2(VM_READ)] = "rd", 652 [ilog2(VM_WRITE)] = "wr", 653 [ilog2(VM_EXEC)] = "ex", 654 [ilog2(VM_SHARED)] = "sh", 655 [ilog2(VM_MAYREAD)] = "mr", 656 [ilog2(VM_MAYWRITE)] = "mw", 657 [ilog2(VM_MAYEXEC)] = "me", 658 [ilog2(VM_MAYSHARE)] = "ms", 659 [ilog2(VM_GROWSDOWN)] = "gd", 660 [ilog2(VM_PFNMAP)] = "pf", 661 [ilog2(VM_LOCKED)] = "lo", 662 [ilog2(VM_IO)] = "io", 663 [ilog2(VM_SEQ_READ)] = "sr", 664 [ilog2(VM_RAND_READ)] = "rr", 665 [ilog2(VM_DONTCOPY)] = "dc", 666 [ilog2(VM_DONTEXPAND)] = "de", 667 [ilog2(VM_ACCOUNT)] = "ac", 668 [ilog2(VM_NORESERVE)] = "nr", 669 [ilog2(VM_HUGETLB)] = "ht", 670 [ilog2(VM_SYNC)] = "sf", 671 [ilog2(VM_ARCH_1)] = "ar", 672 [ilog2(VM_WIPEONFORK)] = "wf", 673 [ilog2(VM_DONTDUMP)] = "dd", 674 #ifdef CONFIG_ARM64_BTI 675 [ilog2(VM_ARM64_BTI)] = "bt", 676 #endif 677 #ifdef CONFIG_MEM_SOFT_DIRTY 678 [ilog2(VM_SOFTDIRTY)] = "sd", 679 #endif 680 [ilog2(VM_MIXEDMAP)] = "mm", 681 [ilog2(VM_HUGEPAGE)] = "hg", 682 [ilog2(VM_NOHUGEPAGE)] = "nh", 683 [ilog2(VM_MERGEABLE)] = "mg", 684 [ilog2(VM_UFFD_MISSING)]= "um", 685 [ilog2(VM_UFFD_WP)] = "uw", 686 #ifdef CONFIG_ARM64_MTE 687 [ilog2(VM_MTE)] = "mt", 688 [ilog2(VM_MTE_ALLOWED)] = "", 689 #endif 690 #ifdef CONFIG_ARCH_HAS_PKEYS 691 /* These come out via ProtectionKey: */ 692 [ilog2(VM_PKEY_BIT0)] = "", 693 [ilog2(VM_PKEY_BIT1)] = "", 694 [ilog2(VM_PKEY_BIT2)] = "", 695 [ilog2(VM_PKEY_BIT3)] = "", 696 #if VM_PKEY_BIT4 697 [ilog2(VM_PKEY_BIT4)] = "", 698 #endif 699 #endif /* CONFIG_ARCH_HAS_PKEYS */ 700 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR 701 [ilog2(VM_UFFD_MINOR)] = "ui", 702 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ 703 }; 704 size_t i; 705 706 seq_puts(m, "VmFlags: "); 707 for (i = 0; i < BITS_PER_LONG; i++) { 708 if (!mnemonics[i][0]) 709 continue; 710 if (vma->vm_flags & (1UL << i)) { 711 seq_putc(m, mnemonics[i][0]); 712 seq_putc(m, mnemonics[i][1]); 713 seq_putc(m, ' '); 714 } 715 } 716 seq_putc(m, '\n'); 717 } 718 719 #ifdef CONFIG_HUGETLB_PAGE 720 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 721 unsigned long addr, unsigned long end, 722 struct mm_walk *walk) 723 { 724 struct mem_size_stats *mss = walk->private; 725 struct vm_area_struct *vma = walk->vma; 726 struct page *page = NULL; 727 728 if (pte_present(*pte)) { 729 page = vm_normal_page(vma, addr, *pte); 730 } else if (is_swap_pte(*pte)) { 731 swp_entry_t swpent = pte_to_swp_entry(*pte); 732 733 if (is_pfn_swap_entry(swpent)) 734 page = pfn_swap_entry_to_page(swpent); 735 } 736 if (page) { 737 int mapcount = page_mapcount(page); 738 739 if (mapcount >= 2) 740 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 741 else 742 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 743 } 744 return 0; 745 } 746 #else 747 #define smaps_hugetlb_range NULL 748 #endif /* HUGETLB_PAGE */ 749 750 static const struct mm_walk_ops smaps_walk_ops = { 751 .pmd_entry = smaps_pte_range, 752 .hugetlb_entry = smaps_hugetlb_range, 753 }; 754 755 static const struct mm_walk_ops smaps_shmem_walk_ops = { 756 .pmd_entry = smaps_pte_range, 757 .hugetlb_entry = smaps_hugetlb_range, 758 .pte_hole = smaps_pte_hole, 759 }; 760 761 /* 762 * Gather mem stats from @vma with the indicated beginning 763 * address @start, and keep them in @mss. 764 * 765 * Use vm_start of @vma as the beginning address if @start is 0. 766 */ 767 static void smap_gather_stats(struct vm_area_struct *vma, 768 struct mem_size_stats *mss, unsigned long start) 769 { 770 const struct mm_walk_ops *ops = &smaps_walk_ops; 771 772 /* Invalid start */ 773 if (start >= vma->vm_end) 774 return; 775 776 #ifdef CONFIG_SHMEM 777 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 778 /* 779 * For shared or readonly shmem mappings we know that all 780 * swapped out pages belong to the shmem object, and we can 781 * obtain the swap value much more efficiently. For private 782 * writable mappings, we might have COW pages that are 783 * not affected by the parent swapped out pages of the shmem 784 * object, so we have to distinguish them during the page walk. 785 * Unless we know that the shmem object (or the part mapped by 786 * our VMA) has no swapped out pages at all. 787 */ 788 unsigned long shmem_swapped = shmem_swap_usage(vma); 789 790 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 791 !(vma->vm_flags & VM_WRITE))) { 792 mss->swap += shmem_swapped; 793 } else { 794 ops = &smaps_shmem_walk_ops; 795 } 796 } 797 #endif 798 /* mmap_lock is held in m_start */ 799 if (!start) 800 walk_page_vma(vma, ops, mss); 801 else 802 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); 803 } 804 805 #define SEQ_PUT_DEC(str, val) \ 806 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 807 808 /* Show the contents common for smaps and smaps_rollup */ 809 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 810 bool rollup_mode) 811 { 812 SEQ_PUT_DEC("Rss: ", mss->resident); 813 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 814 SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT); 815 if (rollup_mode) { 816 /* 817 * These are meaningful only for smaps_rollup, otherwise two of 818 * them are zero, and the other one is the same as Pss. 819 */ 820 SEQ_PUT_DEC(" kB\nPss_Anon: ", 821 mss->pss_anon >> PSS_SHIFT); 822 SEQ_PUT_DEC(" kB\nPss_File: ", 823 mss->pss_file >> PSS_SHIFT); 824 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 825 mss->pss_shmem >> PSS_SHIFT); 826 } 827 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 828 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 829 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 830 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 831 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 832 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 833 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 834 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 835 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 836 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 837 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 838 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 839 mss->private_hugetlb >> 10, 7); 840 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 841 SEQ_PUT_DEC(" kB\nSwapPss: ", 842 mss->swap_pss >> PSS_SHIFT); 843 SEQ_PUT_DEC(" kB\nLocked: ", 844 mss->pss_locked >> PSS_SHIFT); 845 seq_puts(m, " kB\n"); 846 } 847 848 static int show_smap(struct seq_file *m, void *v) 849 { 850 struct vm_area_struct *vma = v; 851 struct mem_size_stats mss; 852 853 memset(&mss, 0, sizeof(mss)); 854 855 smap_gather_stats(vma, &mss, 0); 856 857 show_map_vma(m, vma); 858 859 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 860 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 861 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 862 seq_puts(m, " kB\n"); 863 864 __show_smap(m, &mss, false); 865 866 seq_printf(m, "THPeligible: %d\n", 867 hugepage_vma_check(vma, vma->vm_flags, true, false)); 868 869 if (arch_pkeys_enabled()) 870 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 871 show_smap_vma_flags(m, vma); 872 873 return 0; 874 } 875 876 static int show_smaps_rollup(struct seq_file *m, void *v) 877 { 878 struct proc_maps_private *priv = m->private; 879 struct mem_size_stats mss; 880 struct mm_struct *mm; 881 struct vm_area_struct *vma; 882 unsigned long last_vma_end = 0; 883 int ret = 0; 884 885 priv->task = get_proc_task(priv->inode); 886 if (!priv->task) 887 return -ESRCH; 888 889 mm = priv->mm; 890 if (!mm || !mmget_not_zero(mm)) { 891 ret = -ESRCH; 892 goto out_put_task; 893 } 894 895 memset(&mss, 0, sizeof(mss)); 896 897 ret = mmap_read_lock_killable(mm); 898 if (ret) 899 goto out_put_mm; 900 901 hold_task_mempolicy(priv); 902 903 for (vma = priv->mm->mmap; vma;) { 904 smap_gather_stats(vma, &mss, 0); 905 last_vma_end = vma->vm_end; 906 907 /* 908 * Release mmap_lock temporarily if someone wants to 909 * access it for write request. 910 */ 911 if (mmap_lock_is_contended(mm)) { 912 mmap_read_unlock(mm); 913 ret = mmap_read_lock_killable(mm); 914 if (ret) { 915 release_task_mempolicy(priv); 916 goto out_put_mm; 917 } 918 919 /* 920 * After dropping the lock, there are four cases to 921 * consider. See the following example for explanation. 922 * 923 * +------+------+-----------+ 924 * | VMA1 | VMA2 | VMA3 | 925 * +------+------+-----------+ 926 * | | | | 927 * 4k 8k 16k 400k 928 * 929 * Suppose we drop the lock after reading VMA2 due to 930 * contention, then we get: 931 * 932 * last_vma_end = 16k 933 * 934 * 1) VMA2 is freed, but VMA3 exists: 935 * 936 * find_vma(mm, 16k - 1) will return VMA3. 937 * In this case, just continue from VMA3. 938 * 939 * 2) VMA2 still exists: 940 * 941 * find_vma(mm, 16k - 1) will return VMA2. 942 * Iterate the loop like the original one. 943 * 944 * 3) No more VMAs can be found: 945 * 946 * find_vma(mm, 16k - 1) will return NULL. 947 * No more things to do, just break. 948 * 949 * 4) (last_vma_end - 1) is the middle of a vma (VMA'): 950 * 951 * find_vma(mm, 16k - 1) will return VMA' whose range 952 * contains last_vma_end. 953 * Iterate VMA' from last_vma_end. 954 */ 955 vma = find_vma(mm, last_vma_end - 1); 956 /* Case 3 above */ 957 if (!vma) 958 break; 959 960 /* Case 1 above */ 961 if (vma->vm_start >= last_vma_end) 962 continue; 963 964 /* Case 4 above */ 965 if (vma->vm_end > last_vma_end) 966 smap_gather_stats(vma, &mss, last_vma_end); 967 } 968 /* Case 2 above */ 969 vma = vma->vm_next; 970 } 971 972 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 973 last_vma_end, 0, 0, 0, 0); 974 seq_pad(m, ' '); 975 seq_puts(m, "[rollup]\n"); 976 977 __show_smap(m, &mss, true); 978 979 release_task_mempolicy(priv); 980 mmap_read_unlock(mm); 981 982 out_put_mm: 983 mmput(mm); 984 out_put_task: 985 put_task_struct(priv->task); 986 priv->task = NULL; 987 988 return ret; 989 } 990 #undef SEQ_PUT_DEC 991 992 static const struct seq_operations proc_pid_smaps_op = { 993 .start = m_start, 994 .next = m_next, 995 .stop = m_stop, 996 .show = show_smap 997 }; 998 999 static int pid_smaps_open(struct inode *inode, struct file *file) 1000 { 1001 return do_maps_open(inode, file, &proc_pid_smaps_op); 1002 } 1003 1004 static int smaps_rollup_open(struct inode *inode, struct file *file) 1005 { 1006 int ret; 1007 struct proc_maps_private *priv; 1008 1009 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 1010 if (!priv) 1011 return -ENOMEM; 1012 1013 ret = single_open(file, show_smaps_rollup, priv); 1014 if (ret) 1015 goto out_free; 1016 1017 priv->inode = inode; 1018 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 1019 if (IS_ERR(priv->mm)) { 1020 ret = PTR_ERR(priv->mm); 1021 1022 single_release(inode, file); 1023 goto out_free; 1024 } 1025 1026 return 0; 1027 1028 out_free: 1029 kfree(priv); 1030 return ret; 1031 } 1032 1033 static int smaps_rollup_release(struct inode *inode, struct file *file) 1034 { 1035 struct seq_file *seq = file->private_data; 1036 struct proc_maps_private *priv = seq->private; 1037 1038 if (priv->mm) 1039 mmdrop(priv->mm); 1040 1041 kfree(priv); 1042 return single_release(inode, file); 1043 } 1044 1045 const struct file_operations proc_pid_smaps_operations = { 1046 .open = pid_smaps_open, 1047 .read = seq_read, 1048 .llseek = seq_lseek, 1049 .release = proc_map_release, 1050 }; 1051 1052 const struct file_operations proc_pid_smaps_rollup_operations = { 1053 .open = smaps_rollup_open, 1054 .read = seq_read, 1055 .llseek = seq_lseek, 1056 .release = smaps_rollup_release, 1057 }; 1058 1059 enum clear_refs_types { 1060 CLEAR_REFS_ALL = 1, 1061 CLEAR_REFS_ANON, 1062 CLEAR_REFS_MAPPED, 1063 CLEAR_REFS_SOFT_DIRTY, 1064 CLEAR_REFS_MM_HIWATER_RSS, 1065 CLEAR_REFS_LAST, 1066 }; 1067 1068 struct clear_refs_private { 1069 enum clear_refs_types type; 1070 }; 1071 1072 #ifdef CONFIG_MEM_SOFT_DIRTY 1073 1074 static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1075 { 1076 struct page *page; 1077 1078 if (!pte_write(pte)) 1079 return false; 1080 if (!is_cow_mapping(vma->vm_flags)) 1081 return false; 1082 if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))) 1083 return false; 1084 page = vm_normal_page(vma, addr, pte); 1085 if (!page) 1086 return false; 1087 return page_maybe_dma_pinned(page); 1088 } 1089 1090 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1091 unsigned long addr, pte_t *pte) 1092 { 1093 /* 1094 * The soft-dirty tracker uses #PF-s to catch writes 1095 * to pages, so write-protect the pte as well. See the 1096 * Documentation/admin-guide/mm/soft-dirty.rst for full description 1097 * of how soft-dirty works. 1098 */ 1099 pte_t ptent = *pte; 1100 1101 if (pte_present(ptent)) { 1102 pte_t old_pte; 1103 1104 if (pte_is_pinned(vma, addr, ptent)) 1105 return; 1106 old_pte = ptep_modify_prot_start(vma, addr, pte); 1107 ptent = pte_wrprotect(old_pte); 1108 ptent = pte_clear_soft_dirty(ptent); 1109 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1110 } else if (is_swap_pte(ptent)) { 1111 ptent = pte_swp_clear_soft_dirty(ptent); 1112 set_pte_at(vma->vm_mm, addr, pte, ptent); 1113 } 1114 } 1115 #else 1116 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1117 unsigned long addr, pte_t *pte) 1118 { 1119 } 1120 #endif 1121 1122 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 1123 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1124 unsigned long addr, pmd_t *pmdp) 1125 { 1126 pmd_t old, pmd = *pmdp; 1127 1128 if (pmd_present(pmd)) { 1129 /* See comment in change_huge_pmd() */ 1130 old = pmdp_invalidate(vma, addr, pmdp); 1131 if (pmd_dirty(old)) 1132 pmd = pmd_mkdirty(pmd); 1133 if (pmd_young(old)) 1134 pmd = pmd_mkyoung(pmd); 1135 1136 pmd = pmd_wrprotect(pmd); 1137 pmd = pmd_clear_soft_dirty(pmd); 1138 1139 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1140 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1141 pmd = pmd_swp_clear_soft_dirty(pmd); 1142 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1143 } 1144 } 1145 #else 1146 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1147 unsigned long addr, pmd_t *pmdp) 1148 { 1149 } 1150 #endif 1151 1152 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1153 unsigned long end, struct mm_walk *walk) 1154 { 1155 struct clear_refs_private *cp = walk->private; 1156 struct vm_area_struct *vma = walk->vma; 1157 pte_t *pte, ptent; 1158 spinlock_t *ptl; 1159 struct page *page; 1160 1161 ptl = pmd_trans_huge_lock(pmd, vma); 1162 if (ptl) { 1163 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1164 clear_soft_dirty_pmd(vma, addr, pmd); 1165 goto out; 1166 } 1167 1168 if (!pmd_present(*pmd)) 1169 goto out; 1170 1171 page = pmd_page(*pmd); 1172 1173 /* Clear accessed and referenced bits. */ 1174 pmdp_test_and_clear_young(vma, addr, pmd); 1175 test_and_clear_page_young(page); 1176 ClearPageReferenced(page); 1177 out: 1178 spin_unlock(ptl); 1179 return 0; 1180 } 1181 1182 if (pmd_trans_unstable(pmd)) 1183 return 0; 1184 1185 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1186 for (; addr != end; pte++, addr += PAGE_SIZE) { 1187 ptent = *pte; 1188 1189 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1190 clear_soft_dirty(vma, addr, pte); 1191 continue; 1192 } 1193 1194 if (!pte_present(ptent)) 1195 continue; 1196 1197 page = vm_normal_page(vma, addr, ptent); 1198 if (!page) 1199 continue; 1200 1201 /* Clear accessed and referenced bits. */ 1202 ptep_test_and_clear_young(vma, addr, pte); 1203 test_and_clear_page_young(page); 1204 ClearPageReferenced(page); 1205 } 1206 pte_unmap_unlock(pte - 1, ptl); 1207 cond_resched(); 1208 return 0; 1209 } 1210 1211 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1212 struct mm_walk *walk) 1213 { 1214 struct clear_refs_private *cp = walk->private; 1215 struct vm_area_struct *vma = walk->vma; 1216 1217 if (vma->vm_flags & VM_PFNMAP) 1218 return 1; 1219 1220 /* 1221 * Writing 1 to /proc/pid/clear_refs affects all pages. 1222 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1223 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1224 * Writing 4 to /proc/pid/clear_refs affects all pages. 1225 */ 1226 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1227 return 1; 1228 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1229 return 1; 1230 return 0; 1231 } 1232 1233 static const struct mm_walk_ops clear_refs_walk_ops = { 1234 .pmd_entry = clear_refs_pte_range, 1235 .test_walk = clear_refs_test_walk, 1236 }; 1237 1238 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1239 size_t count, loff_t *ppos) 1240 { 1241 struct task_struct *task; 1242 char buffer[PROC_NUMBUF]; 1243 struct mm_struct *mm; 1244 struct vm_area_struct *vma; 1245 enum clear_refs_types type; 1246 int itype; 1247 int rv; 1248 1249 memset(buffer, 0, sizeof(buffer)); 1250 if (count > sizeof(buffer) - 1) 1251 count = sizeof(buffer) - 1; 1252 if (copy_from_user(buffer, buf, count)) 1253 return -EFAULT; 1254 rv = kstrtoint(strstrip(buffer), 10, &itype); 1255 if (rv < 0) 1256 return rv; 1257 type = (enum clear_refs_types)itype; 1258 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1259 return -EINVAL; 1260 1261 task = get_proc_task(file_inode(file)); 1262 if (!task) 1263 return -ESRCH; 1264 mm = get_task_mm(task); 1265 if (mm) { 1266 struct mmu_notifier_range range; 1267 struct clear_refs_private cp = { 1268 .type = type, 1269 }; 1270 1271 if (mmap_write_lock_killable(mm)) { 1272 count = -EINTR; 1273 goto out_mm; 1274 } 1275 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1276 /* 1277 * Writing 5 to /proc/pid/clear_refs resets the peak 1278 * resident set size to this mm's current rss value. 1279 */ 1280 reset_mm_hiwater_rss(mm); 1281 goto out_unlock; 1282 } 1283 1284 if (type == CLEAR_REFS_SOFT_DIRTY) { 1285 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1286 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1287 continue; 1288 vma->vm_flags &= ~VM_SOFTDIRTY; 1289 vma_set_page_prot(vma); 1290 } 1291 1292 inc_tlb_flush_pending(mm); 1293 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1294 0, NULL, mm, 0, -1UL); 1295 mmu_notifier_invalidate_range_start(&range); 1296 } 1297 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1298 &cp); 1299 if (type == CLEAR_REFS_SOFT_DIRTY) { 1300 mmu_notifier_invalidate_range_end(&range); 1301 flush_tlb_mm(mm); 1302 dec_tlb_flush_pending(mm); 1303 } 1304 out_unlock: 1305 mmap_write_unlock(mm); 1306 out_mm: 1307 mmput(mm); 1308 } 1309 put_task_struct(task); 1310 1311 return count; 1312 } 1313 1314 const struct file_operations proc_clear_refs_operations = { 1315 .write = clear_refs_write, 1316 .llseek = noop_llseek, 1317 }; 1318 1319 typedef struct { 1320 u64 pme; 1321 } pagemap_entry_t; 1322 1323 struct pagemapread { 1324 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1325 pagemap_entry_t *buffer; 1326 bool show_pfn; 1327 }; 1328 1329 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1330 #define PAGEMAP_WALK_MASK (PMD_MASK) 1331 1332 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1333 #define PM_PFRAME_BITS 55 1334 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1335 #define PM_SOFT_DIRTY BIT_ULL(55) 1336 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1337 #define PM_UFFD_WP BIT_ULL(57) 1338 #define PM_FILE BIT_ULL(61) 1339 #define PM_SWAP BIT_ULL(62) 1340 #define PM_PRESENT BIT_ULL(63) 1341 1342 #define PM_END_OF_BUFFER 1 1343 1344 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1345 { 1346 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1347 } 1348 1349 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1350 struct pagemapread *pm) 1351 { 1352 pm->buffer[pm->pos++] = *pme; 1353 if (pm->pos >= pm->len) 1354 return PM_END_OF_BUFFER; 1355 return 0; 1356 } 1357 1358 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1359 __always_unused int depth, struct mm_walk *walk) 1360 { 1361 struct pagemapread *pm = walk->private; 1362 unsigned long addr = start; 1363 int err = 0; 1364 1365 while (addr < end) { 1366 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1367 pagemap_entry_t pme = make_pme(0, 0); 1368 /* End of address space hole, which we mark as non-present. */ 1369 unsigned long hole_end; 1370 1371 if (vma) 1372 hole_end = min(end, vma->vm_start); 1373 else 1374 hole_end = end; 1375 1376 for (; addr < hole_end; addr += PAGE_SIZE) { 1377 err = add_to_pagemap(addr, &pme, pm); 1378 if (err) 1379 goto out; 1380 } 1381 1382 if (!vma) 1383 break; 1384 1385 /* Addresses in the VMA. */ 1386 if (vma->vm_flags & VM_SOFTDIRTY) 1387 pme = make_pme(0, PM_SOFT_DIRTY); 1388 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1389 err = add_to_pagemap(addr, &pme, pm); 1390 if (err) 1391 goto out; 1392 } 1393 } 1394 out: 1395 return err; 1396 } 1397 1398 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1399 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1400 { 1401 u64 frame = 0, flags = 0; 1402 struct page *page = NULL; 1403 bool migration = false; 1404 1405 if (pte_present(pte)) { 1406 if (pm->show_pfn) 1407 frame = pte_pfn(pte); 1408 flags |= PM_PRESENT; 1409 page = vm_normal_page(vma, addr, pte); 1410 if (pte_soft_dirty(pte)) 1411 flags |= PM_SOFT_DIRTY; 1412 if (pte_uffd_wp(pte)) 1413 flags |= PM_UFFD_WP; 1414 } else if (is_swap_pte(pte)) { 1415 swp_entry_t entry; 1416 if (pte_swp_soft_dirty(pte)) 1417 flags |= PM_SOFT_DIRTY; 1418 if (pte_swp_uffd_wp(pte)) 1419 flags |= PM_UFFD_WP; 1420 entry = pte_to_swp_entry(pte); 1421 if (pm->show_pfn) 1422 frame = swp_type(entry) | 1423 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1424 flags |= PM_SWAP; 1425 migration = is_migration_entry(entry); 1426 if (is_pfn_swap_entry(entry)) 1427 page = pfn_swap_entry_to_page(entry); 1428 if (pte_marker_entry_uffd_wp(entry)) 1429 flags |= PM_UFFD_WP; 1430 } 1431 1432 if (page && !PageAnon(page)) 1433 flags |= PM_FILE; 1434 if (page && !migration && page_mapcount(page) == 1) 1435 flags |= PM_MMAP_EXCLUSIVE; 1436 if (vma->vm_flags & VM_SOFTDIRTY) 1437 flags |= PM_SOFT_DIRTY; 1438 1439 return make_pme(frame, flags); 1440 } 1441 1442 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1443 struct mm_walk *walk) 1444 { 1445 struct vm_area_struct *vma = walk->vma; 1446 struct pagemapread *pm = walk->private; 1447 spinlock_t *ptl; 1448 pte_t *pte, *orig_pte; 1449 int err = 0; 1450 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1451 bool migration = false; 1452 1453 ptl = pmd_trans_huge_lock(pmdp, vma); 1454 if (ptl) { 1455 u64 flags = 0, frame = 0; 1456 pmd_t pmd = *pmdp; 1457 struct page *page = NULL; 1458 1459 if (vma->vm_flags & VM_SOFTDIRTY) 1460 flags |= PM_SOFT_DIRTY; 1461 1462 if (pmd_present(pmd)) { 1463 page = pmd_page(pmd); 1464 1465 flags |= PM_PRESENT; 1466 if (pmd_soft_dirty(pmd)) 1467 flags |= PM_SOFT_DIRTY; 1468 if (pmd_uffd_wp(pmd)) 1469 flags |= PM_UFFD_WP; 1470 if (pm->show_pfn) 1471 frame = pmd_pfn(pmd) + 1472 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1473 } 1474 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1475 else if (is_swap_pmd(pmd)) { 1476 swp_entry_t entry = pmd_to_swp_entry(pmd); 1477 unsigned long offset; 1478 1479 if (pm->show_pfn) { 1480 offset = swp_offset(entry) + 1481 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1482 frame = swp_type(entry) | 1483 (offset << MAX_SWAPFILES_SHIFT); 1484 } 1485 flags |= PM_SWAP; 1486 if (pmd_swp_soft_dirty(pmd)) 1487 flags |= PM_SOFT_DIRTY; 1488 if (pmd_swp_uffd_wp(pmd)) 1489 flags |= PM_UFFD_WP; 1490 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1491 migration = is_migration_entry(entry); 1492 page = pfn_swap_entry_to_page(entry); 1493 } 1494 #endif 1495 1496 if (page && !migration && page_mapcount(page) == 1) 1497 flags |= PM_MMAP_EXCLUSIVE; 1498 1499 for (; addr != end; addr += PAGE_SIZE) { 1500 pagemap_entry_t pme = make_pme(frame, flags); 1501 1502 err = add_to_pagemap(addr, &pme, pm); 1503 if (err) 1504 break; 1505 if (pm->show_pfn) { 1506 if (flags & PM_PRESENT) 1507 frame++; 1508 else if (flags & PM_SWAP) 1509 frame += (1 << MAX_SWAPFILES_SHIFT); 1510 } 1511 } 1512 spin_unlock(ptl); 1513 return err; 1514 } 1515 1516 if (pmd_trans_unstable(pmdp)) 1517 return 0; 1518 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1519 1520 /* 1521 * We can assume that @vma always points to a valid one and @end never 1522 * goes beyond vma->vm_end. 1523 */ 1524 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1525 for (; addr < end; pte++, addr += PAGE_SIZE) { 1526 pagemap_entry_t pme; 1527 1528 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1529 err = add_to_pagemap(addr, &pme, pm); 1530 if (err) 1531 break; 1532 } 1533 pte_unmap_unlock(orig_pte, ptl); 1534 1535 cond_resched(); 1536 1537 return err; 1538 } 1539 1540 #ifdef CONFIG_HUGETLB_PAGE 1541 /* This function walks within one hugetlb entry in the single call */ 1542 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1543 unsigned long addr, unsigned long end, 1544 struct mm_walk *walk) 1545 { 1546 struct pagemapread *pm = walk->private; 1547 struct vm_area_struct *vma = walk->vma; 1548 u64 flags = 0, frame = 0; 1549 int err = 0; 1550 pte_t pte; 1551 1552 if (vma->vm_flags & VM_SOFTDIRTY) 1553 flags |= PM_SOFT_DIRTY; 1554 1555 pte = huge_ptep_get(ptep); 1556 if (pte_present(pte)) { 1557 struct page *page = pte_page(pte); 1558 1559 if (!PageAnon(page)) 1560 flags |= PM_FILE; 1561 1562 if (page_mapcount(page) == 1) 1563 flags |= PM_MMAP_EXCLUSIVE; 1564 1565 if (huge_pte_uffd_wp(pte)) 1566 flags |= PM_UFFD_WP; 1567 1568 flags |= PM_PRESENT; 1569 if (pm->show_pfn) 1570 frame = pte_pfn(pte) + 1571 ((addr & ~hmask) >> PAGE_SHIFT); 1572 } else if (pte_swp_uffd_wp_any(pte)) { 1573 flags |= PM_UFFD_WP; 1574 } 1575 1576 for (; addr != end; addr += PAGE_SIZE) { 1577 pagemap_entry_t pme = make_pme(frame, flags); 1578 1579 err = add_to_pagemap(addr, &pme, pm); 1580 if (err) 1581 return err; 1582 if (pm->show_pfn && (flags & PM_PRESENT)) 1583 frame++; 1584 } 1585 1586 cond_resched(); 1587 1588 return err; 1589 } 1590 #else 1591 #define pagemap_hugetlb_range NULL 1592 #endif /* HUGETLB_PAGE */ 1593 1594 static const struct mm_walk_ops pagemap_ops = { 1595 .pmd_entry = pagemap_pmd_range, 1596 .pte_hole = pagemap_pte_hole, 1597 .hugetlb_entry = pagemap_hugetlb_range, 1598 }; 1599 1600 /* 1601 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1602 * 1603 * For each page in the address space, this file contains one 64-bit entry 1604 * consisting of the following: 1605 * 1606 * Bits 0-54 page frame number (PFN) if present 1607 * Bits 0-4 swap type if swapped 1608 * Bits 5-54 swap offset if swapped 1609 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1610 * Bit 56 page exclusively mapped 1611 * Bit 57 pte is uffd-wp write-protected 1612 * Bits 58-60 zero 1613 * Bit 61 page is file-page or shared-anon 1614 * Bit 62 page swapped 1615 * Bit 63 page present 1616 * 1617 * If the page is not present but in swap, then the PFN contains an 1618 * encoding of the swap file number and the page's offset into the 1619 * swap. Unmapped pages return a null PFN. This allows determining 1620 * precisely which pages are mapped (or in swap) and comparing mapped 1621 * pages between processes. 1622 * 1623 * Efficient users of this interface will use /proc/pid/maps to 1624 * determine which areas of memory are actually mapped and llseek to 1625 * skip over unmapped regions. 1626 */ 1627 static ssize_t pagemap_read(struct file *file, char __user *buf, 1628 size_t count, loff_t *ppos) 1629 { 1630 struct mm_struct *mm = file->private_data; 1631 struct pagemapread pm; 1632 unsigned long src; 1633 unsigned long svpfn; 1634 unsigned long start_vaddr; 1635 unsigned long end_vaddr; 1636 int ret = 0, copied = 0; 1637 1638 if (!mm || !mmget_not_zero(mm)) 1639 goto out; 1640 1641 ret = -EINVAL; 1642 /* file position must be aligned */ 1643 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1644 goto out_mm; 1645 1646 ret = 0; 1647 if (!count) 1648 goto out_mm; 1649 1650 /* do not disclose physical addresses: attack vector */ 1651 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1652 1653 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1654 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1655 ret = -ENOMEM; 1656 if (!pm.buffer) 1657 goto out_mm; 1658 1659 src = *ppos; 1660 svpfn = src / PM_ENTRY_BYTES; 1661 end_vaddr = mm->task_size; 1662 1663 /* watch out for wraparound */ 1664 start_vaddr = end_vaddr; 1665 if (svpfn <= (ULONG_MAX >> PAGE_SHIFT)) 1666 start_vaddr = untagged_addr(svpfn << PAGE_SHIFT); 1667 1668 /* Ensure the address is inside the task */ 1669 if (start_vaddr > mm->task_size) 1670 start_vaddr = end_vaddr; 1671 1672 /* 1673 * The odds are that this will stop walking way 1674 * before end_vaddr, because the length of the 1675 * user buffer is tracked in "pm", and the walk 1676 * will stop when we hit the end of the buffer. 1677 */ 1678 ret = 0; 1679 while (count && (start_vaddr < end_vaddr)) { 1680 int len; 1681 unsigned long end; 1682 1683 pm.pos = 0; 1684 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1685 /* overflow ? */ 1686 if (end < start_vaddr || end > end_vaddr) 1687 end = end_vaddr; 1688 ret = mmap_read_lock_killable(mm); 1689 if (ret) 1690 goto out_free; 1691 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1692 mmap_read_unlock(mm); 1693 start_vaddr = end; 1694 1695 len = min(count, PM_ENTRY_BYTES * pm.pos); 1696 if (copy_to_user(buf, pm.buffer, len)) { 1697 ret = -EFAULT; 1698 goto out_free; 1699 } 1700 copied += len; 1701 buf += len; 1702 count -= len; 1703 } 1704 *ppos += copied; 1705 if (!ret || ret == PM_END_OF_BUFFER) 1706 ret = copied; 1707 1708 out_free: 1709 kfree(pm.buffer); 1710 out_mm: 1711 mmput(mm); 1712 out: 1713 return ret; 1714 } 1715 1716 static int pagemap_open(struct inode *inode, struct file *file) 1717 { 1718 struct mm_struct *mm; 1719 1720 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1721 if (IS_ERR(mm)) 1722 return PTR_ERR(mm); 1723 file->private_data = mm; 1724 return 0; 1725 } 1726 1727 static int pagemap_release(struct inode *inode, struct file *file) 1728 { 1729 struct mm_struct *mm = file->private_data; 1730 1731 if (mm) 1732 mmdrop(mm); 1733 return 0; 1734 } 1735 1736 const struct file_operations proc_pagemap_operations = { 1737 .llseek = mem_lseek, /* borrow this */ 1738 .read = pagemap_read, 1739 .open = pagemap_open, 1740 .release = pagemap_release, 1741 }; 1742 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1743 1744 #ifdef CONFIG_NUMA 1745 1746 struct numa_maps { 1747 unsigned long pages; 1748 unsigned long anon; 1749 unsigned long active; 1750 unsigned long writeback; 1751 unsigned long mapcount_max; 1752 unsigned long dirty; 1753 unsigned long swapcache; 1754 unsigned long node[MAX_NUMNODES]; 1755 }; 1756 1757 struct numa_maps_private { 1758 struct proc_maps_private proc_maps; 1759 struct numa_maps md; 1760 }; 1761 1762 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1763 unsigned long nr_pages) 1764 { 1765 int count = page_mapcount(page); 1766 1767 md->pages += nr_pages; 1768 if (pte_dirty || PageDirty(page)) 1769 md->dirty += nr_pages; 1770 1771 if (PageSwapCache(page)) 1772 md->swapcache += nr_pages; 1773 1774 if (PageActive(page) || PageUnevictable(page)) 1775 md->active += nr_pages; 1776 1777 if (PageWriteback(page)) 1778 md->writeback += nr_pages; 1779 1780 if (PageAnon(page)) 1781 md->anon += nr_pages; 1782 1783 if (count > md->mapcount_max) 1784 md->mapcount_max = count; 1785 1786 md->node[page_to_nid(page)] += nr_pages; 1787 } 1788 1789 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1790 unsigned long addr) 1791 { 1792 struct page *page; 1793 int nid; 1794 1795 if (!pte_present(pte)) 1796 return NULL; 1797 1798 page = vm_normal_page(vma, addr, pte); 1799 if (!page || is_zone_device_page(page)) 1800 return NULL; 1801 1802 if (PageReserved(page)) 1803 return NULL; 1804 1805 nid = page_to_nid(page); 1806 if (!node_isset(nid, node_states[N_MEMORY])) 1807 return NULL; 1808 1809 return page; 1810 } 1811 1812 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1813 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1814 struct vm_area_struct *vma, 1815 unsigned long addr) 1816 { 1817 struct page *page; 1818 int nid; 1819 1820 if (!pmd_present(pmd)) 1821 return NULL; 1822 1823 page = vm_normal_page_pmd(vma, addr, pmd); 1824 if (!page) 1825 return NULL; 1826 1827 if (PageReserved(page)) 1828 return NULL; 1829 1830 nid = page_to_nid(page); 1831 if (!node_isset(nid, node_states[N_MEMORY])) 1832 return NULL; 1833 1834 return page; 1835 } 1836 #endif 1837 1838 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1839 unsigned long end, struct mm_walk *walk) 1840 { 1841 struct numa_maps *md = walk->private; 1842 struct vm_area_struct *vma = walk->vma; 1843 spinlock_t *ptl; 1844 pte_t *orig_pte; 1845 pte_t *pte; 1846 1847 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1848 ptl = pmd_trans_huge_lock(pmd, vma); 1849 if (ptl) { 1850 struct page *page; 1851 1852 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1853 if (page) 1854 gather_stats(page, md, pmd_dirty(*pmd), 1855 HPAGE_PMD_SIZE/PAGE_SIZE); 1856 spin_unlock(ptl); 1857 return 0; 1858 } 1859 1860 if (pmd_trans_unstable(pmd)) 1861 return 0; 1862 #endif 1863 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1864 do { 1865 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1866 if (!page) 1867 continue; 1868 gather_stats(page, md, pte_dirty(*pte), 1); 1869 1870 } while (pte++, addr += PAGE_SIZE, addr != end); 1871 pte_unmap_unlock(orig_pte, ptl); 1872 cond_resched(); 1873 return 0; 1874 } 1875 #ifdef CONFIG_HUGETLB_PAGE 1876 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1877 unsigned long addr, unsigned long end, struct mm_walk *walk) 1878 { 1879 pte_t huge_pte = huge_ptep_get(pte); 1880 struct numa_maps *md; 1881 struct page *page; 1882 1883 if (!pte_present(huge_pte)) 1884 return 0; 1885 1886 page = pte_page(huge_pte); 1887 1888 md = walk->private; 1889 gather_stats(page, md, pte_dirty(huge_pte), 1); 1890 return 0; 1891 } 1892 1893 #else 1894 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1895 unsigned long addr, unsigned long end, struct mm_walk *walk) 1896 { 1897 return 0; 1898 } 1899 #endif 1900 1901 static const struct mm_walk_ops show_numa_ops = { 1902 .hugetlb_entry = gather_hugetlb_stats, 1903 .pmd_entry = gather_pte_stats, 1904 }; 1905 1906 /* 1907 * Display pages allocated per node and memory policy via /proc. 1908 */ 1909 static int show_numa_map(struct seq_file *m, void *v) 1910 { 1911 struct numa_maps_private *numa_priv = m->private; 1912 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1913 struct vm_area_struct *vma = v; 1914 struct numa_maps *md = &numa_priv->md; 1915 struct file *file = vma->vm_file; 1916 struct mm_struct *mm = vma->vm_mm; 1917 struct mempolicy *pol; 1918 char buffer[64]; 1919 int nid; 1920 1921 if (!mm) 1922 return 0; 1923 1924 /* Ensure we start with an empty set of numa_maps statistics. */ 1925 memset(md, 0, sizeof(*md)); 1926 1927 pol = __get_vma_policy(vma, vma->vm_start); 1928 if (pol) { 1929 mpol_to_str(buffer, sizeof(buffer), pol); 1930 mpol_cond_put(pol); 1931 } else { 1932 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1933 } 1934 1935 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1936 1937 if (file) { 1938 seq_puts(m, " file="); 1939 seq_file_path(m, file, "\n\t= "); 1940 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1941 seq_puts(m, " heap"); 1942 } else if (is_stack(vma)) { 1943 seq_puts(m, " stack"); 1944 } 1945 1946 if (is_vm_hugetlb_page(vma)) 1947 seq_puts(m, " huge"); 1948 1949 /* mmap_lock is held by m_start */ 1950 walk_page_vma(vma, &show_numa_ops, md); 1951 1952 if (!md->pages) 1953 goto out; 1954 1955 if (md->anon) 1956 seq_printf(m, " anon=%lu", md->anon); 1957 1958 if (md->dirty) 1959 seq_printf(m, " dirty=%lu", md->dirty); 1960 1961 if (md->pages != md->anon && md->pages != md->dirty) 1962 seq_printf(m, " mapped=%lu", md->pages); 1963 1964 if (md->mapcount_max > 1) 1965 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1966 1967 if (md->swapcache) 1968 seq_printf(m, " swapcache=%lu", md->swapcache); 1969 1970 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1971 seq_printf(m, " active=%lu", md->active); 1972 1973 if (md->writeback) 1974 seq_printf(m, " writeback=%lu", md->writeback); 1975 1976 for_each_node_state(nid, N_MEMORY) 1977 if (md->node[nid]) 1978 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1979 1980 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1981 out: 1982 seq_putc(m, '\n'); 1983 return 0; 1984 } 1985 1986 static const struct seq_operations proc_pid_numa_maps_op = { 1987 .start = m_start, 1988 .next = m_next, 1989 .stop = m_stop, 1990 .show = show_numa_map, 1991 }; 1992 1993 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1994 { 1995 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1996 sizeof(struct numa_maps_private)); 1997 } 1998 1999 const struct file_operations proc_pid_numa_maps_operations = { 2000 .open = pid_numa_maps_open, 2001 .read = seq_read, 2002 .llseek = seq_lseek, 2003 .release = proc_map_release, 2004 }; 2005 2006 #endif /* CONFIG_NUMA */ 2007