1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/pagewalk.h> 3 #include <linux/vmacache.h> 4 #include <linux/hugetlb.h> 5 #include <linux/huge_mm.h> 6 #include <linux/mount.h> 7 #include <linux/seq_file.h> 8 #include <linux/highmem.h> 9 #include <linux/ptrace.h> 10 #include <linux/slab.h> 11 #include <linux/pagemap.h> 12 #include <linux/mempolicy.h> 13 #include <linux/rmap.h> 14 #include <linux/swap.h> 15 #include <linux/sched/mm.h> 16 #include <linux/swapops.h> 17 #include <linux/mmu_notifier.h> 18 #include <linux/page_idle.h> 19 #include <linux/shmem_fs.h> 20 #include <linux/uaccess.h> 21 #include <linux/pkeys.h> 22 23 #include <asm/elf.h> 24 #include <asm/tlb.h> 25 #include <asm/tlbflush.h> 26 #include "internal.h" 27 28 #define SEQ_PUT_DEC(str, val) \ 29 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8) 30 void task_mem(struct seq_file *m, struct mm_struct *mm) 31 { 32 unsigned long text, lib, swap, anon, file, shmem; 33 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 34 35 anon = get_mm_counter(mm, MM_ANONPAGES); 36 file = get_mm_counter(mm, MM_FILEPAGES); 37 shmem = get_mm_counter(mm, MM_SHMEMPAGES); 38 39 /* 40 * Note: to minimize their overhead, mm maintains hiwater_vm and 41 * hiwater_rss only when about to *lower* total_vm or rss. Any 42 * collector of these hiwater stats must therefore get total_vm 43 * and rss too, which will usually be the higher. Barriers? not 44 * worth the effort, such snapshots can always be inconsistent. 45 */ 46 hiwater_vm = total_vm = mm->total_vm; 47 if (hiwater_vm < mm->hiwater_vm) 48 hiwater_vm = mm->hiwater_vm; 49 hiwater_rss = total_rss = anon + file + shmem; 50 if (hiwater_rss < mm->hiwater_rss) 51 hiwater_rss = mm->hiwater_rss; 52 53 /* split executable areas between text and lib */ 54 text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK); 55 text = min(text, mm->exec_vm << PAGE_SHIFT); 56 lib = (mm->exec_vm << PAGE_SHIFT) - text; 57 58 swap = get_mm_counter(mm, MM_SWAPENTS); 59 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm); 60 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm); 61 SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm); 62 SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm)); 63 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss); 64 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss); 65 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon); 66 SEQ_PUT_DEC(" kB\nRssFile:\t", file); 67 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem); 68 SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm); 69 SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm); 70 seq_put_decimal_ull_width(m, 71 " kB\nVmExe:\t", text >> 10, 8); 72 seq_put_decimal_ull_width(m, 73 " kB\nVmLib:\t", lib >> 10, 8); 74 seq_put_decimal_ull_width(m, 75 " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8); 76 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap); 77 seq_puts(m, " kB\n"); 78 hugetlb_report_usage(m, mm); 79 } 80 #undef SEQ_PUT_DEC 81 82 unsigned long task_vsize(struct mm_struct *mm) 83 { 84 return PAGE_SIZE * mm->total_vm; 85 } 86 87 unsigned long task_statm(struct mm_struct *mm, 88 unsigned long *shared, unsigned long *text, 89 unsigned long *data, unsigned long *resident) 90 { 91 *shared = get_mm_counter(mm, MM_FILEPAGES) + 92 get_mm_counter(mm, MM_SHMEMPAGES); 93 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 94 >> PAGE_SHIFT; 95 *data = mm->data_vm + mm->stack_vm; 96 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 97 return mm->total_vm; 98 } 99 100 #ifdef CONFIG_NUMA 101 /* 102 * Save get_task_policy() for show_numa_map(). 103 */ 104 static void hold_task_mempolicy(struct proc_maps_private *priv) 105 { 106 struct task_struct *task = priv->task; 107 108 task_lock(task); 109 priv->task_mempolicy = get_task_policy(task); 110 mpol_get(priv->task_mempolicy); 111 task_unlock(task); 112 } 113 static void release_task_mempolicy(struct proc_maps_private *priv) 114 { 115 mpol_put(priv->task_mempolicy); 116 } 117 #else 118 static void hold_task_mempolicy(struct proc_maps_private *priv) 119 { 120 } 121 static void release_task_mempolicy(struct proc_maps_private *priv) 122 { 123 } 124 #endif 125 126 static void *m_start(struct seq_file *m, loff_t *ppos) 127 { 128 struct proc_maps_private *priv = m->private; 129 unsigned long last_addr = *ppos; 130 struct mm_struct *mm; 131 struct vm_area_struct *vma; 132 133 /* See m_next(). Zero at the start or after lseek. */ 134 if (last_addr == -1UL) 135 return NULL; 136 137 priv->task = get_proc_task(priv->inode); 138 if (!priv->task) 139 return ERR_PTR(-ESRCH); 140 141 mm = priv->mm; 142 if (!mm || !mmget_not_zero(mm)) { 143 put_task_struct(priv->task); 144 priv->task = NULL; 145 return NULL; 146 } 147 148 if (mmap_read_lock_killable(mm)) { 149 mmput(mm); 150 put_task_struct(priv->task); 151 priv->task = NULL; 152 return ERR_PTR(-EINTR); 153 } 154 155 hold_task_mempolicy(priv); 156 priv->tail_vma = get_gate_vma(mm); 157 158 vma = find_vma(mm, last_addr); 159 if (vma) 160 return vma; 161 162 return priv->tail_vma; 163 } 164 165 static void *m_next(struct seq_file *m, void *v, loff_t *ppos) 166 { 167 struct proc_maps_private *priv = m->private; 168 struct vm_area_struct *next, *vma = v; 169 170 if (vma == priv->tail_vma) 171 next = NULL; 172 else if (vma->vm_next) 173 next = vma->vm_next; 174 else 175 next = priv->tail_vma; 176 177 *ppos = next ? next->vm_start : -1UL; 178 179 return next; 180 } 181 182 static void m_stop(struct seq_file *m, void *v) 183 { 184 struct proc_maps_private *priv = m->private; 185 struct mm_struct *mm = priv->mm; 186 187 if (!priv->task) 188 return; 189 190 release_task_mempolicy(priv); 191 mmap_read_unlock(mm); 192 mmput(mm); 193 put_task_struct(priv->task); 194 priv->task = NULL; 195 } 196 197 static int proc_maps_open(struct inode *inode, struct file *file, 198 const struct seq_operations *ops, int psize) 199 { 200 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 201 202 if (!priv) 203 return -ENOMEM; 204 205 priv->inode = inode; 206 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 207 if (IS_ERR(priv->mm)) { 208 int err = PTR_ERR(priv->mm); 209 210 seq_release_private(inode, file); 211 return err; 212 } 213 214 return 0; 215 } 216 217 static int proc_map_release(struct inode *inode, struct file *file) 218 { 219 struct seq_file *seq = file->private_data; 220 struct proc_maps_private *priv = seq->private; 221 222 if (priv->mm) 223 mmdrop(priv->mm); 224 225 return seq_release_private(inode, file); 226 } 227 228 static int do_maps_open(struct inode *inode, struct file *file, 229 const struct seq_operations *ops) 230 { 231 return proc_maps_open(inode, file, ops, 232 sizeof(struct proc_maps_private)); 233 } 234 235 /* 236 * Indicate if the VMA is a stack for the given task; for 237 * /proc/PID/maps that is the stack of the main task. 238 */ 239 static int is_stack(struct vm_area_struct *vma) 240 { 241 /* 242 * We make no effort to guess what a given thread considers to be 243 * its "stack". It's not even well-defined for programs written 244 * languages like Go. 245 */ 246 return vma->vm_start <= vma->vm_mm->start_stack && 247 vma->vm_end >= vma->vm_mm->start_stack; 248 } 249 250 static void show_vma_header_prefix(struct seq_file *m, 251 unsigned long start, unsigned long end, 252 vm_flags_t flags, unsigned long long pgoff, 253 dev_t dev, unsigned long ino) 254 { 255 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 256 seq_put_hex_ll(m, NULL, start, 8); 257 seq_put_hex_ll(m, "-", end, 8); 258 seq_putc(m, ' '); 259 seq_putc(m, flags & VM_READ ? 'r' : '-'); 260 seq_putc(m, flags & VM_WRITE ? 'w' : '-'); 261 seq_putc(m, flags & VM_EXEC ? 'x' : '-'); 262 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p'); 263 seq_put_hex_ll(m, " ", pgoff, 8); 264 seq_put_hex_ll(m, " ", MAJOR(dev), 2); 265 seq_put_hex_ll(m, ":", MINOR(dev), 2); 266 seq_put_decimal_ull(m, " ", ino); 267 seq_putc(m, ' '); 268 } 269 270 static void 271 show_map_vma(struct seq_file *m, struct vm_area_struct *vma) 272 { 273 struct mm_struct *mm = vma->vm_mm; 274 struct file *file = vma->vm_file; 275 vm_flags_t flags = vma->vm_flags; 276 unsigned long ino = 0; 277 unsigned long long pgoff = 0; 278 unsigned long start, end; 279 dev_t dev = 0; 280 const char *name = NULL; 281 282 if (file) { 283 struct inode *inode = file_inode(vma->vm_file); 284 dev = inode->i_sb->s_dev; 285 ino = inode->i_ino; 286 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 287 } 288 289 start = vma->vm_start; 290 end = vma->vm_end; 291 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 292 293 /* 294 * Print the dentry name for named mappings, and a 295 * special [heap] marker for the heap: 296 */ 297 if (file) { 298 seq_pad(m, ' '); 299 seq_file_path(m, file, "\n"); 300 goto done; 301 } 302 303 if (vma->vm_ops && vma->vm_ops->name) { 304 name = vma->vm_ops->name(vma); 305 if (name) 306 goto done; 307 } 308 309 name = arch_vma_name(vma); 310 if (!name) { 311 if (!mm) { 312 name = "[vdso]"; 313 goto done; 314 } 315 316 if (vma->vm_start <= mm->brk && 317 vma->vm_end >= mm->start_brk) { 318 name = "[heap]"; 319 goto done; 320 } 321 322 if (is_stack(vma)) 323 name = "[stack]"; 324 } 325 326 done: 327 if (name) { 328 seq_pad(m, ' '); 329 seq_puts(m, name); 330 } 331 seq_putc(m, '\n'); 332 } 333 334 static int show_map(struct seq_file *m, void *v) 335 { 336 show_map_vma(m, v); 337 return 0; 338 } 339 340 static const struct seq_operations proc_pid_maps_op = { 341 .start = m_start, 342 .next = m_next, 343 .stop = m_stop, 344 .show = show_map 345 }; 346 347 static int pid_maps_open(struct inode *inode, struct file *file) 348 { 349 return do_maps_open(inode, file, &proc_pid_maps_op); 350 } 351 352 const struct file_operations proc_pid_maps_operations = { 353 .open = pid_maps_open, 354 .read = seq_read, 355 .llseek = seq_lseek, 356 .release = proc_map_release, 357 }; 358 359 /* 360 * Proportional Set Size(PSS): my share of RSS. 361 * 362 * PSS of a process is the count of pages it has in memory, where each 363 * page is divided by the number of processes sharing it. So if a 364 * process has 1000 pages all to itself, and 1000 shared with one other 365 * process, its PSS will be 1500. 366 * 367 * To keep (accumulated) division errors low, we adopt a 64bit 368 * fixed-point pss counter to minimize division errors. So (pss >> 369 * PSS_SHIFT) would be the real byte count. 370 * 371 * A shift of 12 before division means (assuming 4K page size): 372 * - 1M 3-user-pages add up to 8KB errors; 373 * - supports mapcount up to 2^24, or 16M; 374 * - supports PSS up to 2^52 bytes, or 4PB. 375 */ 376 #define PSS_SHIFT 12 377 378 #ifdef CONFIG_PROC_PAGE_MONITOR 379 struct mem_size_stats { 380 unsigned long resident; 381 unsigned long shared_clean; 382 unsigned long shared_dirty; 383 unsigned long private_clean; 384 unsigned long private_dirty; 385 unsigned long referenced; 386 unsigned long anonymous; 387 unsigned long lazyfree; 388 unsigned long anonymous_thp; 389 unsigned long shmem_thp; 390 unsigned long file_thp; 391 unsigned long swap; 392 unsigned long shared_hugetlb; 393 unsigned long private_hugetlb; 394 u64 pss; 395 u64 pss_anon; 396 u64 pss_file; 397 u64 pss_shmem; 398 u64 pss_locked; 399 u64 swap_pss; 400 bool check_shmem_swap; 401 }; 402 403 static void smaps_page_accumulate(struct mem_size_stats *mss, 404 struct page *page, unsigned long size, unsigned long pss, 405 bool dirty, bool locked, bool private) 406 { 407 mss->pss += pss; 408 409 if (PageAnon(page)) 410 mss->pss_anon += pss; 411 else if (PageSwapBacked(page)) 412 mss->pss_shmem += pss; 413 else 414 mss->pss_file += pss; 415 416 if (locked) 417 mss->pss_locked += pss; 418 419 if (dirty || PageDirty(page)) { 420 if (private) 421 mss->private_dirty += size; 422 else 423 mss->shared_dirty += size; 424 } else { 425 if (private) 426 mss->private_clean += size; 427 else 428 mss->shared_clean += size; 429 } 430 } 431 432 static void smaps_account(struct mem_size_stats *mss, struct page *page, 433 bool compound, bool young, bool dirty, bool locked) 434 { 435 int i, nr = compound ? compound_nr(page) : 1; 436 unsigned long size = nr * PAGE_SIZE; 437 438 /* 439 * First accumulate quantities that depend only on |size| and the type 440 * of the compound page. 441 */ 442 if (PageAnon(page)) { 443 mss->anonymous += size; 444 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 445 mss->lazyfree += size; 446 } 447 448 mss->resident += size; 449 /* Accumulate the size in pages that have been accessed. */ 450 if (young || page_is_young(page) || PageReferenced(page)) 451 mss->referenced += size; 452 453 /* 454 * Then accumulate quantities that may depend on sharing, or that may 455 * differ page-by-page. 456 * 457 * page_count(page) == 1 guarantees the page is mapped exactly once. 458 * If any subpage of the compound page mapped with PTE it would elevate 459 * page_count(). 460 */ 461 if (page_count(page) == 1) { 462 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, 463 locked, true); 464 return; 465 } 466 for (i = 0; i < nr; i++, page++) { 467 int mapcount = page_mapcount(page); 468 unsigned long pss = PAGE_SIZE << PSS_SHIFT; 469 if (mapcount >= 2) 470 pss /= mapcount; 471 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked, 472 mapcount < 2); 473 } 474 } 475 476 #ifdef CONFIG_SHMEM 477 static int smaps_pte_hole(unsigned long addr, unsigned long end, 478 __always_unused int depth, struct mm_walk *walk) 479 { 480 struct mem_size_stats *mss = walk->private; 481 482 mss->swap += shmem_partial_swap_usage( 483 walk->vma->vm_file->f_mapping, addr, end); 484 485 return 0; 486 } 487 #else 488 #define smaps_pte_hole NULL 489 #endif /* CONFIG_SHMEM */ 490 491 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 492 struct mm_walk *walk) 493 { 494 struct mem_size_stats *mss = walk->private; 495 struct vm_area_struct *vma = walk->vma; 496 bool locked = !!(vma->vm_flags & VM_LOCKED); 497 struct page *page = NULL; 498 499 if (pte_present(*pte)) { 500 page = vm_normal_page(vma, addr, *pte); 501 } else if (is_swap_pte(*pte)) { 502 swp_entry_t swpent = pte_to_swp_entry(*pte); 503 504 if (!non_swap_entry(swpent)) { 505 int mapcount; 506 507 mss->swap += PAGE_SIZE; 508 mapcount = swp_swapcount(swpent); 509 if (mapcount >= 2) { 510 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 511 512 do_div(pss_delta, mapcount); 513 mss->swap_pss += pss_delta; 514 } else { 515 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 516 } 517 } else if (is_migration_entry(swpent)) 518 page = migration_entry_to_page(swpent); 519 else if (is_device_private_entry(swpent)) 520 page = device_private_entry_to_page(swpent); 521 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 522 && pte_none(*pte))) { 523 page = find_get_entry(vma->vm_file->f_mapping, 524 linear_page_index(vma, addr)); 525 if (!page) 526 return; 527 528 if (xa_is_value(page)) 529 mss->swap += PAGE_SIZE; 530 else 531 put_page(page); 532 533 return; 534 } 535 536 if (!page) 537 return; 538 539 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked); 540 } 541 542 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 543 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 544 struct mm_walk *walk) 545 { 546 struct mem_size_stats *mss = walk->private; 547 struct vm_area_struct *vma = walk->vma; 548 bool locked = !!(vma->vm_flags & VM_LOCKED); 549 struct page *page = NULL; 550 551 if (pmd_present(*pmd)) { 552 /* FOLL_DUMP will return -EFAULT on huge zero page */ 553 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 554 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { 555 swp_entry_t entry = pmd_to_swp_entry(*pmd); 556 557 if (is_migration_entry(entry)) 558 page = migration_entry_to_page(entry); 559 } 560 if (IS_ERR_OR_NULL(page)) 561 return; 562 if (PageAnon(page)) 563 mss->anonymous_thp += HPAGE_PMD_SIZE; 564 else if (PageSwapBacked(page)) 565 mss->shmem_thp += HPAGE_PMD_SIZE; 566 else if (is_zone_device_page(page)) 567 /* pass */; 568 else 569 mss->file_thp += HPAGE_PMD_SIZE; 570 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked); 571 } 572 #else 573 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 574 struct mm_walk *walk) 575 { 576 } 577 #endif 578 579 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 580 struct mm_walk *walk) 581 { 582 struct vm_area_struct *vma = walk->vma; 583 pte_t *pte; 584 spinlock_t *ptl; 585 586 ptl = pmd_trans_huge_lock(pmd, vma); 587 if (ptl) { 588 smaps_pmd_entry(pmd, addr, walk); 589 spin_unlock(ptl); 590 goto out; 591 } 592 593 if (pmd_trans_unstable(pmd)) 594 goto out; 595 /* 596 * The mmap_lock held all the way back in m_start() is what 597 * keeps khugepaged out of here and from collapsing things 598 * in here. 599 */ 600 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 601 for (; addr != end; pte++, addr += PAGE_SIZE) 602 smaps_pte_entry(pte, addr, walk); 603 pte_unmap_unlock(pte - 1, ptl); 604 out: 605 cond_resched(); 606 return 0; 607 } 608 609 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 610 { 611 /* 612 * Don't forget to update Documentation/ on changes. 613 */ 614 static const char mnemonics[BITS_PER_LONG][2] = { 615 /* 616 * In case if we meet a flag we don't know about. 617 */ 618 [0 ... (BITS_PER_LONG-1)] = "??", 619 620 [ilog2(VM_READ)] = "rd", 621 [ilog2(VM_WRITE)] = "wr", 622 [ilog2(VM_EXEC)] = "ex", 623 [ilog2(VM_SHARED)] = "sh", 624 [ilog2(VM_MAYREAD)] = "mr", 625 [ilog2(VM_MAYWRITE)] = "mw", 626 [ilog2(VM_MAYEXEC)] = "me", 627 [ilog2(VM_MAYSHARE)] = "ms", 628 [ilog2(VM_GROWSDOWN)] = "gd", 629 [ilog2(VM_PFNMAP)] = "pf", 630 [ilog2(VM_DENYWRITE)] = "dw", 631 [ilog2(VM_LOCKED)] = "lo", 632 [ilog2(VM_IO)] = "io", 633 [ilog2(VM_SEQ_READ)] = "sr", 634 [ilog2(VM_RAND_READ)] = "rr", 635 [ilog2(VM_DONTCOPY)] = "dc", 636 [ilog2(VM_DONTEXPAND)] = "de", 637 [ilog2(VM_ACCOUNT)] = "ac", 638 [ilog2(VM_NORESERVE)] = "nr", 639 [ilog2(VM_HUGETLB)] = "ht", 640 [ilog2(VM_SYNC)] = "sf", 641 [ilog2(VM_ARCH_1)] = "ar", 642 [ilog2(VM_WIPEONFORK)] = "wf", 643 [ilog2(VM_DONTDUMP)] = "dd", 644 #ifdef CONFIG_ARM64_BTI 645 [ilog2(VM_ARM64_BTI)] = "bt", 646 #endif 647 #ifdef CONFIG_MEM_SOFT_DIRTY 648 [ilog2(VM_SOFTDIRTY)] = "sd", 649 #endif 650 [ilog2(VM_MIXEDMAP)] = "mm", 651 [ilog2(VM_HUGEPAGE)] = "hg", 652 [ilog2(VM_NOHUGEPAGE)] = "nh", 653 [ilog2(VM_MERGEABLE)] = "mg", 654 [ilog2(VM_UFFD_MISSING)]= "um", 655 [ilog2(VM_UFFD_WP)] = "uw", 656 #ifdef CONFIG_ARCH_HAS_PKEYS 657 /* These come out via ProtectionKey: */ 658 [ilog2(VM_PKEY_BIT0)] = "", 659 [ilog2(VM_PKEY_BIT1)] = "", 660 [ilog2(VM_PKEY_BIT2)] = "", 661 [ilog2(VM_PKEY_BIT3)] = "", 662 #if VM_PKEY_BIT4 663 [ilog2(VM_PKEY_BIT4)] = "", 664 #endif 665 #endif /* CONFIG_ARCH_HAS_PKEYS */ 666 }; 667 size_t i; 668 669 seq_puts(m, "VmFlags: "); 670 for (i = 0; i < BITS_PER_LONG; i++) { 671 if (!mnemonics[i][0]) 672 continue; 673 if (vma->vm_flags & (1UL << i)) { 674 seq_putc(m, mnemonics[i][0]); 675 seq_putc(m, mnemonics[i][1]); 676 seq_putc(m, ' '); 677 } 678 } 679 seq_putc(m, '\n'); 680 } 681 682 #ifdef CONFIG_HUGETLB_PAGE 683 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 684 unsigned long addr, unsigned long end, 685 struct mm_walk *walk) 686 { 687 struct mem_size_stats *mss = walk->private; 688 struct vm_area_struct *vma = walk->vma; 689 struct page *page = NULL; 690 691 if (pte_present(*pte)) { 692 page = vm_normal_page(vma, addr, *pte); 693 } else if (is_swap_pte(*pte)) { 694 swp_entry_t swpent = pte_to_swp_entry(*pte); 695 696 if (is_migration_entry(swpent)) 697 page = migration_entry_to_page(swpent); 698 else if (is_device_private_entry(swpent)) 699 page = device_private_entry_to_page(swpent); 700 } 701 if (page) { 702 int mapcount = page_mapcount(page); 703 704 if (mapcount >= 2) 705 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 706 else 707 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 708 } 709 return 0; 710 } 711 #else 712 #define smaps_hugetlb_range NULL 713 #endif /* HUGETLB_PAGE */ 714 715 static const struct mm_walk_ops smaps_walk_ops = { 716 .pmd_entry = smaps_pte_range, 717 .hugetlb_entry = smaps_hugetlb_range, 718 }; 719 720 static const struct mm_walk_ops smaps_shmem_walk_ops = { 721 .pmd_entry = smaps_pte_range, 722 .hugetlb_entry = smaps_hugetlb_range, 723 .pte_hole = smaps_pte_hole, 724 }; 725 726 static void smap_gather_stats(struct vm_area_struct *vma, 727 struct mem_size_stats *mss) 728 { 729 #ifdef CONFIG_SHMEM 730 /* In case of smaps_rollup, reset the value from previous vma */ 731 mss->check_shmem_swap = false; 732 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 733 /* 734 * For shared or readonly shmem mappings we know that all 735 * swapped out pages belong to the shmem object, and we can 736 * obtain the swap value much more efficiently. For private 737 * writable mappings, we might have COW pages that are 738 * not affected by the parent swapped out pages of the shmem 739 * object, so we have to distinguish them during the page walk. 740 * Unless we know that the shmem object (or the part mapped by 741 * our VMA) has no swapped out pages at all. 742 */ 743 unsigned long shmem_swapped = shmem_swap_usage(vma); 744 745 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 746 !(vma->vm_flags & VM_WRITE)) { 747 mss->swap += shmem_swapped; 748 } else { 749 mss->check_shmem_swap = true; 750 walk_page_vma(vma, &smaps_shmem_walk_ops, mss); 751 return; 752 } 753 } 754 #endif 755 /* mmap_lock is held in m_start */ 756 walk_page_vma(vma, &smaps_walk_ops, mss); 757 } 758 759 #define SEQ_PUT_DEC(str, val) \ 760 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 761 762 /* Show the contents common for smaps and smaps_rollup */ 763 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 764 bool rollup_mode) 765 { 766 SEQ_PUT_DEC("Rss: ", mss->resident); 767 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 768 if (rollup_mode) { 769 /* 770 * These are meaningful only for smaps_rollup, otherwise two of 771 * them are zero, and the other one is the same as Pss. 772 */ 773 SEQ_PUT_DEC(" kB\nPss_Anon: ", 774 mss->pss_anon >> PSS_SHIFT); 775 SEQ_PUT_DEC(" kB\nPss_File: ", 776 mss->pss_file >> PSS_SHIFT); 777 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 778 mss->pss_shmem >> PSS_SHIFT); 779 } 780 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 781 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 782 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 783 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 784 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 785 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 786 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 787 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 788 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 789 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 790 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 791 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 792 mss->private_hugetlb >> 10, 7); 793 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 794 SEQ_PUT_DEC(" kB\nSwapPss: ", 795 mss->swap_pss >> PSS_SHIFT); 796 SEQ_PUT_DEC(" kB\nLocked: ", 797 mss->pss_locked >> PSS_SHIFT); 798 seq_puts(m, " kB\n"); 799 } 800 801 static int show_smap(struct seq_file *m, void *v) 802 { 803 struct vm_area_struct *vma = v; 804 struct mem_size_stats mss; 805 806 memset(&mss, 0, sizeof(mss)); 807 808 smap_gather_stats(vma, &mss); 809 810 show_map_vma(m, vma); 811 812 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 813 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 814 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 815 seq_puts(m, " kB\n"); 816 817 __show_smap(m, &mss, false); 818 819 seq_printf(m, "THPeligible: %d\n", 820 transparent_hugepage_enabled(vma)); 821 822 if (arch_pkeys_enabled()) 823 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 824 show_smap_vma_flags(m, vma); 825 826 return 0; 827 } 828 829 static int show_smaps_rollup(struct seq_file *m, void *v) 830 { 831 struct proc_maps_private *priv = m->private; 832 struct mem_size_stats mss; 833 struct mm_struct *mm; 834 struct vm_area_struct *vma; 835 unsigned long last_vma_end = 0; 836 int ret = 0; 837 838 priv->task = get_proc_task(priv->inode); 839 if (!priv->task) 840 return -ESRCH; 841 842 mm = priv->mm; 843 if (!mm || !mmget_not_zero(mm)) { 844 ret = -ESRCH; 845 goto out_put_task; 846 } 847 848 memset(&mss, 0, sizeof(mss)); 849 850 ret = mmap_read_lock_killable(mm); 851 if (ret) 852 goto out_put_mm; 853 854 hold_task_mempolicy(priv); 855 856 for (vma = priv->mm->mmap; vma; vma = vma->vm_next) { 857 smap_gather_stats(vma, &mss); 858 last_vma_end = vma->vm_end; 859 } 860 861 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 862 last_vma_end, 0, 0, 0, 0); 863 seq_pad(m, ' '); 864 seq_puts(m, "[rollup]\n"); 865 866 __show_smap(m, &mss, true); 867 868 release_task_mempolicy(priv); 869 mmap_read_unlock(mm); 870 871 out_put_mm: 872 mmput(mm); 873 out_put_task: 874 put_task_struct(priv->task); 875 priv->task = NULL; 876 877 return ret; 878 } 879 #undef SEQ_PUT_DEC 880 881 static const struct seq_operations proc_pid_smaps_op = { 882 .start = m_start, 883 .next = m_next, 884 .stop = m_stop, 885 .show = show_smap 886 }; 887 888 static int pid_smaps_open(struct inode *inode, struct file *file) 889 { 890 return do_maps_open(inode, file, &proc_pid_smaps_op); 891 } 892 893 static int smaps_rollup_open(struct inode *inode, struct file *file) 894 { 895 int ret; 896 struct proc_maps_private *priv; 897 898 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 899 if (!priv) 900 return -ENOMEM; 901 902 ret = single_open(file, show_smaps_rollup, priv); 903 if (ret) 904 goto out_free; 905 906 priv->inode = inode; 907 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 908 if (IS_ERR(priv->mm)) { 909 ret = PTR_ERR(priv->mm); 910 911 single_release(inode, file); 912 goto out_free; 913 } 914 915 return 0; 916 917 out_free: 918 kfree(priv); 919 return ret; 920 } 921 922 static int smaps_rollup_release(struct inode *inode, struct file *file) 923 { 924 struct seq_file *seq = file->private_data; 925 struct proc_maps_private *priv = seq->private; 926 927 if (priv->mm) 928 mmdrop(priv->mm); 929 930 kfree(priv); 931 return single_release(inode, file); 932 } 933 934 const struct file_operations proc_pid_smaps_operations = { 935 .open = pid_smaps_open, 936 .read = seq_read, 937 .llseek = seq_lseek, 938 .release = proc_map_release, 939 }; 940 941 const struct file_operations proc_pid_smaps_rollup_operations = { 942 .open = smaps_rollup_open, 943 .read = seq_read, 944 .llseek = seq_lseek, 945 .release = smaps_rollup_release, 946 }; 947 948 enum clear_refs_types { 949 CLEAR_REFS_ALL = 1, 950 CLEAR_REFS_ANON, 951 CLEAR_REFS_MAPPED, 952 CLEAR_REFS_SOFT_DIRTY, 953 CLEAR_REFS_MM_HIWATER_RSS, 954 CLEAR_REFS_LAST, 955 }; 956 957 struct clear_refs_private { 958 enum clear_refs_types type; 959 }; 960 961 #ifdef CONFIG_MEM_SOFT_DIRTY 962 static inline void clear_soft_dirty(struct vm_area_struct *vma, 963 unsigned long addr, pte_t *pte) 964 { 965 /* 966 * The soft-dirty tracker uses #PF-s to catch writes 967 * to pages, so write-protect the pte as well. See the 968 * Documentation/admin-guide/mm/soft-dirty.rst for full description 969 * of how soft-dirty works. 970 */ 971 pte_t ptent = *pte; 972 973 if (pte_present(ptent)) { 974 pte_t old_pte; 975 976 old_pte = ptep_modify_prot_start(vma, addr, pte); 977 ptent = pte_wrprotect(old_pte); 978 ptent = pte_clear_soft_dirty(ptent); 979 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 980 } else if (is_swap_pte(ptent)) { 981 ptent = pte_swp_clear_soft_dirty(ptent); 982 set_pte_at(vma->vm_mm, addr, pte, ptent); 983 } 984 } 985 #else 986 static inline void clear_soft_dirty(struct vm_area_struct *vma, 987 unsigned long addr, pte_t *pte) 988 { 989 } 990 #endif 991 992 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 993 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 994 unsigned long addr, pmd_t *pmdp) 995 { 996 pmd_t old, pmd = *pmdp; 997 998 if (pmd_present(pmd)) { 999 /* See comment in change_huge_pmd() */ 1000 old = pmdp_invalidate(vma, addr, pmdp); 1001 if (pmd_dirty(old)) 1002 pmd = pmd_mkdirty(pmd); 1003 if (pmd_young(old)) 1004 pmd = pmd_mkyoung(pmd); 1005 1006 pmd = pmd_wrprotect(pmd); 1007 pmd = pmd_clear_soft_dirty(pmd); 1008 1009 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1010 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1011 pmd = pmd_swp_clear_soft_dirty(pmd); 1012 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1013 } 1014 } 1015 #else 1016 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1017 unsigned long addr, pmd_t *pmdp) 1018 { 1019 } 1020 #endif 1021 1022 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1023 unsigned long end, struct mm_walk *walk) 1024 { 1025 struct clear_refs_private *cp = walk->private; 1026 struct vm_area_struct *vma = walk->vma; 1027 pte_t *pte, ptent; 1028 spinlock_t *ptl; 1029 struct page *page; 1030 1031 ptl = pmd_trans_huge_lock(pmd, vma); 1032 if (ptl) { 1033 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1034 clear_soft_dirty_pmd(vma, addr, pmd); 1035 goto out; 1036 } 1037 1038 if (!pmd_present(*pmd)) 1039 goto out; 1040 1041 page = pmd_page(*pmd); 1042 1043 /* Clear accessed and referenced bits. */ 1044 pmdp_test_and_clear_young(vma, addr, pmd); 1045 test_and_clear_page_young(page); 1046 ClearPageReferenced(page); 1047 out: 1048 spin_unlock(ptl); 1049 return 0; 1050 } 1051 1052 if (pmd_trans_unstable(pmd)) 1053 return 0; 1054 1055 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1056 for (; addr != end; pte++, addr += PAGE_SIZE) { 1057 ptent = *pte; 1058 1059 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1060 clear_soft_dirty(vma, addr, pte); 1061 continue; 1062 } 1063 1064 if (!pte_present(ptent)) 1065 continue; 1066 1067 page = vm_normal_page(vma, addr, ptent); 1068 if (!page) 1069 continue; 1070 1071 /* Clear accessed and referenced bits. */ 1072 ptep_test_and_clear_young(vma, addr, pte); 1073 test_and_clear_page_young(page); 1074 ClearPageReferenced(page); 1075 } 1076 pte_unmap_unlock(pte - 1, ptl); 1077 cond_resched(); 1078 return 0; 1079 } 1080 1081 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1082 struct mm_walk *walk) 1083 { 1084 struct clear_refs_private *cp = walk->private; 1085 struct vm_area_struct *vma = walk->vma; 1086 1087 if (vma->vm_flags & VM_PFNMAP) 1088 return 1; 1089 1090 /* 1091 * Writing 1 to /proc/pid/clear_refs affects all pages. 1092 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1093 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1094 * Writing 4 to /proc/pid/clear_refs affects all pages. 1095 */ 1096 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1097 return 1; 1098 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1099 return 1; 1100 return 0; 1101 } 1102 1103 static const struct mm_walk_ops clear_refs_walk_ops = { 1104 .pmd_entry = clear_refs_pte_range, 1105 .test_walk = clear_refs_test_walk, 1106 }; 1107 1108 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1109 size_t count, loff_t *ppos) 1110 { 1111 struct task_struct *task; 1112 char buffer[PROC_NUMBUF]; 1113 struct mm_struct *mm; 1114 struct vm_area_struct *vma; 1115 enum clear_refs_types type; 1116 struct mmu_gather tlb; 1117 int itype; 1118 int rv; 1119 1120 memset(buffer, 0, sizeof(buffer)); 1121 if (count > sizeof(buffer) - 1) 1122 count = sizeof(buffer) - 1; 1123 if (copy_from_user(buffer, buf, count)) 1124 return -EFAULT; 1125 rv = kstrtoint(strstrip(buffer), 10, &itype); 1126 if (rv < 0) 1127 return rv; 1128 type = (enum clear_refs_types)itype; 1129 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1130 return -EINVAL; 1131 1132 task = get_proc_task(file_inode(file)); 1133 if (!task) 1134 return -ESRCH; 1135 mm = get_task_mm(task); 1136 if (mm) { 1137 struct mmu_notifier_range range; 1138 struct clear_refs_private cp = { 1139 .type = type, 1140 }; 1141 1142 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1143 if (mmap_write_lock_killable(mm)) { 1144 count = -EINTR; 1145 goto out_mm; 1146 } 1147 1148 /* 1149 * Writing 5 to /proc/pid/clear_refs resets the peak 1150 * resident set size to this mm's current rss value. 1151 */ 1152 reset_mm_hiwater_rss(mm); 1153 mmap_write_unlock(mm); 1154 goto out_mm; 1155 } 1156 1157 if (mmap_read_lock_killable(mm)) { 1158 count = -EINTR; 1159 goto out_mm; 1160 } 1161 tlb_gather_mmu(&tlb, mm, 0, -1); 1162 if (type == CLEAR_REFS_SOFT_DIRTY) { 1163 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1164 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1165 continue; 1166 mmap_read_unlock(mm); 1167 if (mmap_write_lock_killable(mm)) { 1168 count = -EINTR; 1169 goto out_mm; 1170 } 1171 /* 1172 * Avoid to modify vma->vm_flags 1173 * without locked ops while the 1174 * coredump reads the vm_flags. 1175 */ 1176 if (!mmget_still_valid(mm)) { 1177 /* 1178 * Silently return "count" 1179 * like if get_task_mm() 1180 * failed. FIXME: should this 1181 * function have returned 1182 * -ESRCH if get_task_mm() 1183 * failed like if 1184 * get_proc_task() fails? 1185 */ 1186 mmap_write_unlock(mm); 1187 goto out_mm; 1188 } 1189 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1190 vma->vm_flags &= ~VM_SOFTDIRTY; 1191 vma_set_page_prot(vma); 1192 } 1193 mmap_write_downgrade(mm); 1194 break; 1195 } 1196 1197 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1198 0, NULL, mm, 0, -1UL); 1199 mmu_notifier_invalidate_range_start(&range); 1200 } 1201 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1202 &cp); 1203 if (type == CLEAR_REFS_SOFT_DIRTY) 1204 mmu_notifier_invalidate_range_end(&range); 1205 tlb_finish_mmu(&tlb, 0, -1); 1206 mmap_read_unlock(mm); 1207 out_mm: 1208 mmput(mm); 1209 } 1210 put_task_struct(task); 1211 1212 return count; 1213 } 1214 1215 const struct file_operations proc_clear_refs_operations = { 1216 .write = clear_refs_write, 1217 .llseek = noop_llseek, 1218 }; 1219 1220 typedef struct { 1221 u64 pme; 1222 } pagemap_entry_t; 1223 1224 struct pagemapread { 1225 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1226 pagemap_entry_t *buffer; 1227 bool show_pfn; 1228 }; 1229 1230 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1231 #define PAGEMAP_WALK_MASK (PMD_MASK) 1232 1233 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1234 #define PM_PFRAME_BITS 55 1235 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1236 #define PM_SOFT_DIRTY BIT_ULL(55) 1237 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1238 #define PM_FILE BIT_ULL(61) 1239 #define PM_SWAP BIT_ULL(62) 1240 #define PM_PRESENT BIT_ULL(63) 1241 1242 #define PM_END_OF_BUFFER 1 1243 1244 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1245 { 1246 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1247 } 1248 1249 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1250 struct pagemapread *pm) 1251 { 1252 pm->buffer[pm->pos++] = *pme; 1253 if (pm->pos >= pm->len) 1254 return PM_END_OF_BUFFER; 1255 return 0; 1256 } 1257 1258 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1259 __always_unused int depth, struct mm_walk *walk) 1260 { 1261 struct pagemapread *pm = walk->private; 1262 unsigned long addr = start; 1263 int err = 0; 1264 1265 while (addr < end) { 1266 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1267 pagemap_entry_t pme = make_pme(0, 0); 1268 /* End of address space hole, which we mark as non-present. */ 1269 unsigned long hole_end; 1270 1271 if (vma) 1272 hole_end = min(end, vma->vm_start); 1273 else 1274 hole_end = end; 1275 1276 for (; addr < hole_end; addr += PAGE_SIZE) { 1277 err = add_to_pagemap(addr, &pme, pm); 1278 if (err) 1279 goto out; 1280 } 1281 1282 if (!vma) 1283 break; 1284 1285 /* Addresses in the VMA. */ 1286 if (vma->vm_flags & VM_SOFTDIRTY) 1287 pme = make_pme(0, PM_SOFT_DIRTY); 1288 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1289 err = add_to_pagemap(addr, &pme, pm); 1290 if (err) 1291 goto out; 1292 } 1293 } 1294 out: 1295 return err; 1296 } 1297 1298 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1299 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1300 { 1301 u64 frame = 0, flags = 0; 1302 struct page *page = NULL; 1303 1304 if (pte_present(pte)) { 1305 if (pm->show_pfn) 1306 frame = pte_pfn(pte); 1307 flags |= PM_PRESENT; 1308 page = vm_normal_page(vma, addr, pte); 1309 if (pte_soft_dirty(pte)) 1310 flags |= PM_SOFT_DIRTY; 1311 } else if (is_swap_pte(pte)) { 1312 swp_entry_t entry; 1313 if (pte_swp_soft_dirty(pte)) 1314 flags |= PM_SOFT_DIRTY; 1315 entry = pte_to_swp_entry(pte); 1316 if (pm->show_pfn) 1317 frame = swp_type(entry) | 1318 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1319 flags |= PM_SWAP; 1320 if (is_migration_entry(entry)) 1321 page = migration_entry_to_page(entry); 1322 1323 if (is_device_private_entry(entry)) 1324 page = device_private_entry_to_page(entry); 1325 } 1326 1327 if (page && !PageAnon(page)) 1328 flags |= PM_FILE; 1329 if (page && page_mapcount(page) == 1) 1330 flags |= PM_MMAP_EXCLUSIVE; 1331 if (vma->vm_flags & VM_SOFTDIRTY) 1332 flags |= PM_SOFT_DIRTY; 1333 1334 return make_pme(frame, flags); 1335 } 1336 1337 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1338 struct mm_walk *walk) 1339 { 1340 struct vm_area_struct *vma = walk->vma; 1341 struct pagemapread *pm = walk->private; 1342 spinlock_t *ptl; 1343 pte_t *pte, *orig_pte; 1344 int err = 0; 1345 1346 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1347 ptl = pmd_trans_huge_lock(pmdp, vma); 1348 if (ptl) { 1349 u64 flags = 0, frame = 0; 1350 pmd_t pmd = *pmdp; 1351 struct page *page = NULL; 1352 1353 if (vma->vm_flags & VM_SOFTDIRTY) 1354 flags |= PM_SOFT_DIRTY; 1355 1356 if (pmd_present(pmd)) { 1357 page = pmd_page(pmd); 1358 1359 flags |= PM_PRESENT; 1360 if (pmd_soft_dirty(pmd)) 1361 flags |= PM_SOFT_DIRTY; 1362 if (pm->show_pfn) 1363 frame = pmd_pfn(pmd) + 1364 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1365 } 1366 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1367 else if (is_swap_pmd(pmd)) { 1368 swp_entry_t entry = pmd_to_swp_entry(pmd); 1369 unsigned long offset; 1370 1371 if (pm->show_pfn) { 1372 offset = swp_offset(entry) + 1373 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1374 frame = swp_type(entry) | 1375 (offset << MAX_SWAPFILES_SHIFT); 1376 } 1377 flags |= PM_SWAP; 1378 if (pmd_swp_soft_dirty(pmd)) 1379 flags |= PM_SOFT_DIRTY; 1380 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1381 page = migration_entry_to_page(entry); 1382 } 1383 #endif 1384 1385 if (page && page_mapcount(page) == 1) 1386 flags |= PM_MMAP_EXCLUSIVE; 1387 1388 for (; addr != end; addr += PAGE_SIZE) { 1389 pagemap_entry_t pme = make_pme(frame, flags); 1390 1391 err = add_to_pagemap(addr, &pme, pm); 1392 if (err) 1393 break; 1394 if (pm->show_pfn) { 1395 if (flags & PM_PRESENT) 1396 frame++; 1397 else if (flags & PM_SWAP) 1398 frame += (1 << MAX_SWAPFILES_SHIFT); 1399 } 1400 } 1401 spin_unlock(ptl); 1402 return err; 1403 } 1404 1405 if (pmd_trans_unstable(pmdp)) 1406 return 0; 1407 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1408 1409 /* 1410 * We can assume that @vma always points to a valid one and @end never 1411 * goes beyond vma->vm_end. 1412 */ 1413 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1414 for (; addr < end; pte++, addr += PAGE_SIZE) { 1415 pagemap_entry_t pme; 1416 1417 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1418 err = add_to_pagemap(addr, &pme, pm); 1419 if (err) 1420 break; 1421 } 1422 pte_unmap_unlock(orig_pte, ptl); 1423 1424 cond_resched(); 1425 1426 return err; 1427 } 1428 1429 #ifdef CONFIG_HUGETLB_PAGE 1430 /* This function walks within one hugetlb entry in the single call */ 1431 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1432 unsigned long addr, unsigned long end, 1433 struct mm_walk *walk) 1434 { 1435 struct pagemapread *pm = walk->private; 1436 struct vm_area_struct *vma = walk->vma; 1437 u64 flags = 0, frame = 0; 1438 int err = 0; 1439 pte_t pte; 1440 1441 if (vma->vm_flags & VM_SOFTDIRTY) 1442 flags |= PM_SOFT_DIRTY; 1443 1444 pte = huge_ptep_get(ptep); 1445 if (pte_present(pte)) { 1446 struct page *page = pte_page(pte); 1447 1448 if (!PageAnon(page)) 1449 flags |= PM_FILE; 1450 1451 if (page_mapcount(page) == 1) 1452 flags |= PM_MMAP_EXCLUSIVE; 1453 1454 flags |= PM_PRESENT; 1455 if (pm->show_pfn) 1456 frame = pte_pfn(pte) + 1457 ((addr & ~hmask) >> PAGE_SHIFT); 1458 } 1459 1460 for (; addr != end; addr += PAGE_SIZE) { 1461 pagemap_entry_t pme = make_pme(frame, flags); 1462 1463 err = add_to_pagemap(addr, &pme, pm); 1464 if (err) 1465 return err; 1466 if (pm->show_pfn && (flags & PM_PRESENT)) 1467 frame++; 1468 } 1469 1470 cond_resched(); 1471 1472 return err; 1473 } 1474 #else 1475 #define pagemap_hugetlb_range NULL 1476 #endif /* HUGETLB_PAGE */ 1477 1478 static const struct mm_walk_ops pagemap_ops = { 1479 .pmd_entry = pagemap_pmd_range, 1480 .pte_hole = pagemap_pte_hole, 1481 .hugetlb_entry = pagemap_hugetlb_range, 1482 }; 1483 1484 /* 1485 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1486 * 1487 * For each page in the address space, this file contains one 64-bit entry 1488 * consisting of the following: 1489 * 1490 * Bits 0-54 page frame number (PFN) if present 1491 * Bits 0-4 swap type if swapped 1492 * Bits 5-54 swap offset if swapped 1493 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1494 * Bit 56 page exclusively mapped 1495 * Bits 57-60 zero 1496 * Bit 61 page is file-page or shared-anon 1497 * Bit 62 page swapped 1498 * Bit 63 page present 1499 * 1500 * If the page is not present but in swap, then the PFN contains an 1501 * encoding of the swap file number and the page's offset into the 1502 * swap. Unmapped pages return a null PFN. This allows determining 1503 * precisely which pages are mapped (or in swap) and comparing mapped 1504 * pages between processes. 1505 * 1506 * Efficient users of this interface will use /proc/pid/maps to 1507 * determine which areas of memory are actually mapped and llseek to 1508 * skip over unmapped regions. 1509 */ 1510 static ssize_t pagemap_read(struct file *file, char __user *buf, 1511 size_t count, loff_t *ppos) 1512 { 1513 struct mm_struct *mm = file->private_data; 1514 struct pagemapread pm; 1515 unsigned long src; 1516 unsigned long svpfn; 1517 unsigned long start_vaddr; 1518 unsigned long end_vaddr; 1519 int ret = 0, copied = 0; 1520 1521 if (!mm || !mmget_not_zero(mm)) 1522 goto out; 1523 1524 ret = -EINVAL; 1525 /* file position must be aligned */ 1526 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1527 goto out_mm; 1528 1529 ret = 0; 1530 if (!count) 1531 goto out_mm; 1532 1533 /* do not disclose physical addresses: attack vector */ 1534 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1535 1536 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1537 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1538 ret = -ENOMEM; 1539 if (!pm.buffer) 1540 goto out_mm; 1541 1542 src = *ppos; 1543 svpfn = src / PM_ENTRY_BYTES; 1544 start_vaddr = svpfn << PAGE_SHIFT; 1545 end_vaddr = mm->task_size; 1546 1547 /* watch out for wraparound */ 1548 if (svpfn > mm->task_size >> PAGE_SHIFT) 1549 start_vaddr = end_vaddr; 1550 1551 /* 1552 * The odds are that this will stop walking way 1553 * before end_vaddr, because the length of the 1554 * user buffer is tracked in "pm", and the walk 1555 * will stop when we hit the end of the buffer. 1556 */ 1557 ret = 0; 1558 while (count && (start_vaddr < end_vaddr)) { 1559 int len; 1560 unsigned long end; 1561 1562 pm.pos = 0; 1563 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1564 /* overflow ? */ 1565 if (end < start_vaddr || end > end_vaddr) 1566 end = end_vaddr; 1567 ret = mmap_read_lock_killable(mm); 1568 if (ret) 1569 goto out_free; 1570 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1571 mmap_read_unlock(mm); 1572 start_vaddr = end; 1573 1574 len = min(count, PM_ENTRY_BYTES * pm.pos); 1575 if (copy_to_user(buf, pm.buffer, len)) { 1576 ret = -EFAULT; 1577 goto out_free; 1578 } 1579 copied += len; 1580 buf += len; 1581 count -= len; 1582 } 1583 *ppos += copied; 1584 if (!ret || ret == PM_END_OF_BUFFER) 1585 ret = copied; 1586 1587 out_free: 1588 kfree(pm.buffer); 1589 out_mm: 1590 mmput(mm); 1591 out: 1592 return ret; 1593 } 1594 1595 static int pagemap_open(struct inode *inode, struct file *file) 1596 { 1597 struct mm_struct *mm; 1598 1599 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1600 if (IS_ERR(mm)) 1601 return PTR_ERR(mm); 1602 file->private_data = mm; 1603 return 0; 1604 } 1605 1606 static int pagemap_release(struct inode *inode, struct file *file) 1607 { 1608 struct mm_struct *mm = file->private_data; 1609 1610 if (mm) 1611 mmdrop(mm); 1612 return 0; 1613 } 1614 1615 const struct file_operations proc_pagemap_operations = { 1616 .llseek = mem_lseek, /* borrow this */ 1617 .read = pagemap_read, 1618 .open = pagemap_open, 1619 .release = pagemap_release, 1620 }; 1621 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1622 1623 #ifdef CONFIG_NUMA 1624 1625 struct numa_maps { 1626 unsigned long pages; 1627 unsigned long anon; 1628 unsigned long active; 1629 unsigned long writeback; 1630 unsigned long mapcount_max; 1631 unsigned long dirty; 1632 unsigned long swapcache; 1633 unsigned long node[MAX_NUMNODES]; 1634 }; 1635 1636 struct numa_maps_private { 1637 struct proc_maps_private proc_maps; 1638 struct numa_maps md; 1639 }; 1640 1641 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1642 unsigned long nr_pages) 1643 { 1644 int count = page_mapcount(page); 1645 1646 md->pages += nr_pages; 1647 if (pte_dirty || PageDirty(page)) 1648 md->dirty += nr_pages; 1649 1650 if (PageSwapCache(page)) 1651 md->swapcache += nr_pages; 1652 1653 if (PageActive(page) || PageUnevictable(page)) 1654 md->active += nr_pages; 1655 1656 if (PageWriteback(page)) 1657 md->writeback += nr_pages; 1658 1659 if (PageAnon(page)) 1660 md->anon += nr_pages; 1661 1662 if (count > md->mapcount_max) 1663 md->mapcount_max = count; 1664 1665 md->node[page_to_nid(page)] += nr_pages; 1666 } 1667 1668 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1669 unsigned long addr) 1670 { 1671 struct page *page; 1672 int nid; 1673 1674 if (!pte_present(pte)) 1675 return NULL; 1676 1677 page = vm_normal_page(vma, addr, pte); 1678 if (!page) 1679 return NULL; 1680 1681 if (PageReserved(page)) 1682 return NULL; 1683 1684 nid = page_to_nid(page); 1685 if (!node_isset(nid, node_states[N_MEMORY])) 1686 return NULL; 1687 1688 return page; 1689 } 1690 1691 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1692 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1693 struct vm_area_struct *vma, 1694 unsigned long addr) 1695 { 1696 struct page *page; 1697 int nid; 1698 1699 if (!pmd_present(pmd)) 1700 return NULL; 1701 1702 page = vm_normal_page_pmd(vma, addr, pmd); 1703 if (!page) 1704 return NULL; 1705 1706 if (PageReserved(page)) 1707 return NULL; 1708 1709 nid = page_to_nid(page); 1710 if (!node_isset(nid, node_states[N_MEMORY])) 1711 return NULL; 1712 1713 return page; 1714 } 1715 #endif 1716 1717 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1718 unsigned long end, struct mm_walk *walk) 1719 { 1720 struct numa_maps *md = walk->private; 1721 struct vm_area_struct *vma = walk->vma; 1722 spinlock_t *ptl; 1723 pte_t *orig_pte; 1724 pte_t *pte; 1725 1726 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1727 ptl = pmd_trans_huge_lock(pmd, vma); 1728 if (ptl) { 1729 struct page *page; 1730 1731 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1732 if (page) 1733 gather_stats(page, md, pmd_dirty(*pmd), 1734 HPAGE_PMD_SIZE/PAGE_SIZE); 1735 spin_unlock(ptl); 1736 return 0; 1737 } 1738 1739 if (pmd_trans_unstable(pmd)) 1740 return 0; 1741 #endif 1742 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1743 do { 1744 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1745 if (!page) 1746 continue; 1747 gather_stats(page, md, pte_dirty(*pte), 1); 1748 1749 } while (pte++, addr += PAGE_SIZE, addr != end); 1750 pte_unmap_unlock(orig_pte, ptl); 1751 cond_resched(); 1752 return 0; 1753 } 1754 #ifdef CONFIG_HUGETLB_PAGE 1755 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1756 unsigned long addr, unsigned long end, struct mm_walk *walk) 1757 { 1758 pte_t huge_pte = huge_ptep_get(pte); 1759 struct numa_maps *md; 1760 struct page *page; 1761 1762 if (!pte_present(huge_pte)) 1763 return 0; 1764 1765 page = pte_page(huge_pte); 1766 if (!page) 1767 return 0; 1768 1769 md = walk->private; 1770 gather_stats(page, md, pte_dirty(huge_pte), 1); 1771 return 0; 1772 } 1773 1774 #else 1775 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1776 unsigned long addr, unsigned long end, struct mm_walk *walk) 1777 { 1778 return 0; 1779 } 1780 #endif 1781 1782 static const struct mm_walk_ops show_numa_ops = { 1783 .hugetlb_entry = gather_hugetlb_stats, 1784 .pmd_entry = gather_pte_stats, 1785 }; 1786 1787 /* 1788 * Display pages allocated per node and memory policy via /proc. 1789 */ 1790 static int show_numa_map(struct seq_file *m, void *v) 1791 { 1792 struct numa_maps_private *numa_priv = m->private; 1793 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1794 struct vm_area_struct *vma = v; 1795 struct numa_maps *md = &numa_priv->md; 1796 struct file *file = vma->vm_file; 1797 struct mm_struct *mm = vma->vm_mm; 1798 struct mempolicy *pol; 1799 char buffer[64]; 1800 int nid; 1801 1802 if (!mm) 1803 return 0; 1804 1805 /* Ensure we start with an empty set of numa_maps statistics. */ 1806 memset(md, 0, sizeof(*md)); 1807 1808 pol = __get_vma_policy(vma, vma->vm_start); 1809 if (pol) { 1810 mpol_to_str(buffer, sizeof(buffer), pol); 1811 mpol_cond_put(pol); 1812 } else { 1813 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1814 } 1815 1816 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1817 1818 if (file) { 1819 seq_puts(m, " file="); 1820 seq_file_path(m, file, "\n\t= "); 1821 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1822 seq_puts(m, " heap"); 1823 } else if (is_stack(vma)) { 1824 seq_puts(m, " stack"); 1825 } 1826 1827 if (is_vm_hugetlb_page(vma)) 1828 seq_puts(m, " huge"); 1829 1830 /* mmap_lock is held by m_start */ 1831 walk_page_vma(vma, &show_numa_ops, md); 1832 1833 if (!md->pages) 1834 goto out; 1835 1836 if (md->anon) 1837 seq_printf(m, " anon=%lu", md->anon); 1838 1839 if (md->dirty) 1840 seq_printf(m, " dirty=%lu", md->dirty); 1841 1842 if (md->pages != md->anon && md->pages != md->dirty) 1843 seq_printf(m, " mapped=%lu", md->pages); 1844 1845 if (md->mapcount_max > 1) 1846 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1847 1848 if (md->swapcache) 1849 seq_printf(m, " swapcache=%lu", md->swapcache); 1850 1851 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1852 seq_printf(m, " active=%lu", md->active); 1853 1854 if (md->writeback) 1855 seq_printf(m, " writeback=%lu", md->writeback); 1856 1857 for_each_node_state(nid, N_MEMORY) 1858 if (md->node[nid]) 1859 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1860 1861 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1862 out: 1863 seq_putc(m, '\n'); 1864 return 0; 1865 } 1866 1867 static const struct seq_operations proc_pid_numa_maps_op = { 1868 .start = m_start, 1869 .next = m_next, 1870 .stop = m_stop, 1871 .show = show_numa_map, 1872 }; 1873 1874 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1875 { 1876 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1877 sizeof(struct numa_maps_private)); 1878 } 1879 1880 const struct file_operations proc_pid_numa_maps_operations = { 1881 .open = pid_numa_maps_open, 1882 .read = seq_read, 1883 .llseek = seq_lseek, 1884 .release = proc_map_release, 1885 }; 1886 1887 #endif /* CONFIG_NUMA */ 1888