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 = xa_load(&vma->vm_file->f_mapping->i_pages, 524 linear_page_index(vma, addr)); 525 if (xa_is_value(page)) 526 mss->swap += PAGE_SIZE; 527 return; 528 } 529 530 if (!page) 531 return; 532 533 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked); 534 } 535 536 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 537 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 538 struct mm_walk *walk) 539 { 540 struct mem_size_stats *mss = walk->private; 541 struct vm_area_struct *vma = walk->vma; 542 bool locked = !!(vma->vm_flags & VM_LOCKED); 543 struct page *page = NULL; 544 545 if (pmd_present(*pmd)) { 546 /* FOLL_DUMP will return -EFAULT on huge zero page */ 547 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 548 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { 549 swp_entry_t entry = pmd_to_swp_entry(*pmd); 550 551 if (is_migration_entry(entry)) 552 page = migration_entry_to_page(entry); 553 } 554 if (IS_ERR_OR_NULL(page)) 555 return; 556 if (PageAnon(page)) 557 mss->anonymous_thp += HPAGE_PMD_SIZE; 558 else if (PageSwapBacked(page)) 559 mss->shmem_thp += HPAGE_PMD_SIZE; 560 else if (is_zone_device_page(page)) 561 /* pass */; 562 else 563 mss->file_thp += HPAGE_PMD_SIZE; 564 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked); 565 } 566 #else 567 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 568 struct mm_walk *walk) 569 { 570 } 571 #endif 572 573 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 574 struct mm_walk *walk) 575 { 576 struct vm_area_struct *vma = walk->vma; 577 pte_t *pte; 578 spinlock_t *ptl; 579 580 ptl = pmd_trans_huge_lock(pmd, vma); 581 if (ptl) { 582 smaps_pmd_entry(pmd, addr, walk); 583 spin_unlock(ptl); 584 goto out; 585 } 586 587 if (pmd_trans_unstable(pmd)) 588 goto out; 589 /* 590 * The mmap_lock held all the way back in m_start() is what 591 * keeps khugepaged out of here and from collapsing things 592 * in here. 593 */ 594 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 595 for (; addr != end; pte++, addr += PAGE_SIZE) 596 smaps_pte_entry(pte, addr, walk); 597 pte_unmap_unlock(pte - 1, ptl); 598 out: 599 cond_resched(); 600 return 0; 601 } 602 603 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 604 { 605 /* 606 * Don't forget to update Documentation/ on changes. 607 */ 608 static const char mnemonics[BITS_PER_LONG][2] = { 609 /* 610 * In case if we meet a flag we don't know about. 611 */ 612 [0 ... (BITS_PER_LONG-1)] = "??", 613 614 [ilog2(VM_READ)] = "rd", 615 [ilog2(VM_WRITE)] = "wr", 616 [ilog2(VM_EXEC)] = "ex", 617 [ilog2(VM_SHARED)] = "sh", 618 [ilog2(VM_MAYREAD)] = "mr", 619 [ilog2(VM_MAYWRITE)] = "mw", 620 [ilog2(VM_MAYEXEC)] = "me", 621 [ilog2(VM_MAYSHARE)] = "ms", 622 [ilog2(VM_GROWSDOWN)] = "gd", 623 [ilog2(VM_PFNMAP)] = "pf", 624 [ilog2(VM_DENYWRITE)] = "dw", 625 [ilog2(VM_LOCKED)] = "lo", 626 [ilog2(VM_IO)] = "io", 627 [ilog2(VM_SEQ_READ)] = "sr", 628 [ilog2(VM_RAND_READ)] = "rr", 629 [ilog2(VM_DONTCOPY)] = "dc", 630 [ilog2(VM_DONTEXPAND)] = "de", 631 [ilog2(VM_ACCOUNT)] = "ac", 632 [ilog2(VM_NORESERVE)] = "nr", 633 [ilog2(VM_HUGETLB)] = "ht", 634 [ilog2(VM_SYNC)] = "sf", 635 [ilog2(VM_ARCH_1)] = "ar", 636 [ilog2(VM_WIPEONFORK)] = "wf", 637 [ilog2(VM_DONTDUMP)] = "dd", 638 #ifdef CONFIG_ARM64_BTI 639 [ilog2(VM_ARM64_BTI)] = "bt", 640 #endif 641 #ifdef CONFIG_MEM_SOFT_DIRTY 642 [ilog2(VM_SOFTDIRTY)] = "sd", 643 #endif 644 [ilog2(VM_MIXEDMAP)] = "mm", 645 [ilog2(VM_HUGEPAGE)] = "hg", 646 [ilog2(VM_NOHUGEPAGE)] = "nh", 647 [ilog2(VM_MERGEABLE)] = "mg", 648 [ilog2(VM_UFFD_MISSING)]= "um", 649 [ilog2(VM_UFFD_WP)] = "uw", 650 #ifdef CONFIG_ARM64_MTE 651 [ilog2(VM_MTE)] = "mt", 652 [ilog2(VM_MTE_ALLOWED)] = "", 653 #endif 654 #ifdef CONFIG_ARCH_HAS_PKEYS 655 /* These come out via ProtectionKey: */ 656 [ilog2(VM_PKEY_BIT0)] = "", 657 [ilog2(VM_PKEY_BIT1)] = "", 658 [ilog2(VM_PKEY_BIT2)] = "", 659 [ilog2(VM_PKEY_BIT3)] = "", 660 #if VM_PKEY_BIT4 661 [ilog2(VM_PKEY_BIT4)] = "", 662 #endif 663 #endif /* CONFIG_ARCH_HAS_PKEYS */ 664 }; 665 size_t i; 666 667 seq_puts(m, "VmFlags: "); 668 for (i = 0; i < BITS_PER_LONG; i++) { 669 if (!mnemonics[i][0]) 670 continue; 671 if (vma->vm_flags & (1UL << i)) { 672 seq_putc(m, mnemonics[i][0]); 673 seq_putc(m, mnemonics[i][1]); 674 seq_putc(m, ' '); 675 } 676 } 677 seq_putc(m, '\n'); 678 } 679 680 #ifdef CONFIG_HUGETLB_PAGE 681 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 682 unsigned long addr, unsigned long end, 683 struct mm_walk *walk) 684 { 685 struct mem_size_stats *mss = walk->private; 686 struct vm_area_struct *vma = walk->vma; 687 struct page *page = NULL; 688 689 if (pte_present(*pte)) { 690 page = vm_normal_page(vma, addr, *pte); 691 } else if (is_swap_pte(*pte)) { 692 swp_entry_t swpent = pte_to_swp_entry(*pte); 693 694 if (is_migration_entry(swpent)) 695 page = migration_entry_to_page(swpent); 696 else if (is_device_private_entry(swpent)) 697 page = device_private_entry_to_page(swpent); 698 } 699 if (page) { 700 int mapcount = page_mapcount(page); 701 702 if (mapcount >= 2) 703 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 704 else 705 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 706 } 707 return 0; 708 } 709 #else 710 #define smaps_hugetlb_range NULL 711 #endif /* HUGETLB_PAGE */ 712 713 static const struct mm_walk_ops smaps_walk_ops = { 714 .pmd_entry = smaps_pte_range, 715 .hugetlb_entry = smaps_hugetlb_range, 716 }; 717 718 static const struct mm_walk_ops smaps_shmem_walk_ops = { 719 .pmd_entry = smaps_pte_range, 720 .hugetlb_entry = smaps_hugetlb_range, 721 .pte_hole = smaps_pte_hole, 722 }; 723 724 /* 725 * Gather mem stats from @vma with the indicated beginning 726 * address @start, and keep them in @mss. 727 * 728 * Use vm_start of @vma as the beginning address if @start is 0. 729 */ 730 static void smap_gather_stats(struct vm_area_struct *vma, 731 struct mem_size_stats *mss, unsigned long start) 732 { 733 const struct mm_walk_ops *ops = &smaps_walk_ops; 734 735 /* Invalid start */ 736 if (start >= vma->vm_end) 737 return; 738 739 #ifdef CONFIG_SHMEM 740 /* In case of smaps_rollup, reset the value from previous vma */ 741 mss->check_shmem_swap = false; 742 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 743 /* 744 * For shared or readonly shmem mappings we know that all 745 * swapped out pages belong to the shmem object, and we can 746 * obtain the swap value much more efficiently. For private 747 * writable mappings, we might have COW pages that are 748 * not affected by the parent swapped out pages of the shmem 749 * object, so we have to distinguish them during the page walk. 750 * Unless we know that the shmem object (or the part mapped by 751 * our VMA) has no swapped out pages at all. 752 */ 753 unsigned long shmem_swapped = shmem_swap_usage(vma); 754 755 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 756 !(vma->vm_flags & VM_WRITE))) { 757 mss->swap += shmem_swapped; 758 } else { 759 mss->check_shmem_swap = true; 760 ops = &smaps_shmem_walk_ops; 761 } 762 } 763 #endif 764 /* mmap_lock is held in m_start */ 765 if (!start) 766 walk_page_vma(vma, ops, mss); 767 else 768 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); 769 } 770 771 #define SEQ_PUT_DEC(str, val) \ 772 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 773 774 /* Show the contents common for smaps and smaps_rollup */ 775 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 776 bool rollup_mode) 777 { 778 SEQ_PUT_DEC("Rss: ", mss->resident); 779 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 780 if (rollup_mode) { 781 /* 782 * These are meaningful only for smaps_rollup, otherwise two of 783 * them are zero, and the other one is the same as Pss. 784 */ 785 SEQ_PUT_DEC(" kB\nPss_Anon: ", 786 mss->pss_anon >> PSS_SHIFT); 787 SEQ_PUT_DEC(" kB\nPss_File: ", 788 mss->pss_file >> PSS_SHIFT); 789 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 790 mss->pss_shmem >> PSS_SHIFT); 791 } 792 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 793 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 794 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 795 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 796 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 797 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 798 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 799 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 800 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 801 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 802 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 803 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 804 mss->private_hugetlb >> 10, 7); 805 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 806 SEQ_PUT_DEC(" kB\nSwapPss: ", 807 mss->swap_pss >> PSS_SHIFT); 808 SEQ_PUT_DEC(" kB\nLocked: ", 809 mss->pss_locked >> PSS_SHIFT); 810 seq_puts(m, " kB\n"); 811 } 812 813 static int show_smap(struct seq_file *m, void *v) 814 { 815 struct vm_area_struct *vma = v; 816 struct mem_size_stats mss; 817 818 memset(&mss, 0, sizeof(mss)); 819 820 smap_gather_stats(vma, &mss, 0); 821 822 show_map_vma(m, vma); 823 824 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 825 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 826 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 827 seq_puts(m, " kB\n"); 828 829 __show_smap(m, &mss, false); 830 831 seq_printf(m, "THPeligible: %d\n", 832 transparent_hugepage_enabled(vma)); 833 834 if (arch_pkeys_enabled()) 835 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 836 show_smap_vma_flags(m, vma); 837 838 return 0; 839 } 840 841 static int show_smaps_rollup(struct seq_file *m, void *v) 842 { 843 struct proc_maps_private *priv = m->private; 844 struct mem_size_stats mss; 845 struct mm_struct *mm; 846 struct vm_area_struct *vma; 847 unsigned long last_vma_end = 0; 848 int ret = 0; 849 850 priv->task = get_proc_task(priv->inode); 851 if (!priv->task) 852 return -ESRCH; 853 854 mm = priv->mm; 855 if (!mm || !mmget_not_zero(mm)) { 856 ret = -ESRCH; 857 goto out_put_task; 858 } 859 860 memset(&mss, 0, sizeof(mss)); 861 862 ret = mmap_read_lock_killable(mm); 863 if (ret) 864 goto out_put_mm; 865 866 hold_task_mempolicy(priv); 867 868 for (vma = priv->mm->mmap; vma;) { 869 smap_gather_stats(vma, &mss, 0); 870 last_vma_end = vma->vm_end; 871 872 /* 873 * Release mmap_lock temporarily if someone wants to 874 * access it for write request. 875 */ 876 if (mmap_lock_is_contended(mm)) { 877 mmap_read_unlock(mm); 878 ret = mmap_read_lock_killable(mm); 879 if (ret) { 880 release_task_mempolicy(priv); 881 goto out_put_mm; 882 } 883 884 /* 885 * After dropping the lock, there are four cases to 886 * consider. See the following example for explanation. 887 * 888 * +------+------+-----------+ 889 * | VMA1 | VMA2 | VMA3 | 890 * +------+------+-----------+ 891 * | | | | 892 * 4k 8k 16k 400k 893 * 894 * Suppose we drop the lock after reading VMA2 due to 895 * contention, then we get: 896 * 897 * last_vma_end = 16k 898 * 899 * 1) VMA2 is freed, but VMA3 exists: 900 * 901 * find_vma(mm, 16k - 1) will return VMA3. 902 * In this case, just continue from VMA3. 903 * 904 * 2) VMA2 still exists: 905 * 906 * find_vma(mm, 16k - 1) will return VMA2. 907 * Iterate the loop like the original one. 908 * 909 * 3) No more VMAs can be found: 910 * 911 * find_vma(mm, 16k - 1) will return NULL. 912 * No more things to do, just break. 913 * 914 * 4) (last_vma_end - 1) is the middle of a vma (VMA'): 915 * 916 * find_vma(mm, 16k - 1) will return VMA' whose range 917 * contains last_vma_end. 918 * Iterate VMA' from last_vma_end. 919 */ 920 vma = find_vma(mm, last_vma_end - 1); 921 /* Case 3 above */ 922 if (!vma) 923 break; 924 925 /* Case 1 above */ 926 if (vma->vm_start >= last_vma_end) 927 continue; 928 929 /* Case 4 above */ 930 if (vma->vm_end > last_vma_end) 931 smap_gather_stats(vma, &mss, last_vma_end); 932 } 933 /* Case 2 above */ 934 vma = vma->vm_next; 935 } 936 937 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 938 last_vma_end, 0, 0, 0, 0); 939 seq_pad(m, ' '); 940 seq_puts(m, "[rollup]\n"); 941 942 __show_smap(m, &mss, true); 943 944 release_task_mempolicy(priv); 945 mmap_read_unlock(mm); 946 947 out_put_mm: 948 mmput(mm); 949 out_put_task: 950 put_task_struct(priv->task); 951 priv->task = NULL; 952 953 return ret; 954 } 955 #undef SEQ_PUT_DEC 956 957 static const struct seq_operations proc_pid_smaps_op = { 958 .start = m_start, 959 .next = m_next, 960 .stop = m_stop, 961 .show = show_smap 962 }; 963 964 static int pid_smaps_open(struct inode *inode, struct file *file) 965 { 966 return do_maps_open(inode, file, &proc_pid_smaps_op); 967 } 968 969 static int smaps_rollup_open(struct inode *inode, struct file *file) 970 { 971 int ret; 972 struct proc_maps_private *priv; 973 974 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 975 if (!priv) 976 return -ENOMEM; 977 978 ret = single_open(file, show_smaps_rollup, priv); 979 if (ret) 980 goto out_free; 981 982 priv->inode = inode; 983 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 984 if (IS_ERR(priv->mm)) { 985 ret = PTR_ERR(priv->mm); 986 987 single_release(inode, file); 988 goto out_free; 989 } 990 991 return 0; 992 993 out_free: 994 kfree(priv); 995 return ret; 996 } 997 998 static int smaps_rollup_release(struct inode *inode, struct file *file) 999 { 1000 struct seq_file *seq = file->private_data; 1001 struct proc_maps_private *priv = seq->private; 1002 1003 if (priv->mm) 1004 mmdrop(priv->mm); 1005 1006 kfree(priv); 1007 return single_release(inode, file); 1008 } 1009 1010 const struct file_operations proc_pid_smaps_operations = { 1011 .open = pid_smaps_open, 1012 .read = seq_read, 1013 .llseek = seq_lseek, 1014 .release = proc_map_release, 1015 }; 1016 1017 const struct file_operations proc_pid_smaps_rollup_operations = { 1018 .open = smaps_rollup_open, 1019 .read = seq_read, 1020 .llseek = seq_lseek, 1021 .release = smaps_rollup_release, 1022 }; 1023 1024 enum clear_refs_types { 1025 CLEAR_REFS_ALL = 1, 1026 CLEAR_REFS_ANON, 1027 CLEAR_REFS_MAPPED, 1028 CLEAR_REFS_SOFT_DIRTY, 1029 CLEAR_REFS_MM_HIWATER_RSS, 1030 CLEAR_REFS_LAST, 1031 }; 1032 1033 struct clear_refs_private { 1034 enum clear_refs_types type; 1035 }; 1036 1037 #ifdef CONFIG_MEM_SOFT_DIRTY 1038 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1039 unsigned long addr, pte_t *pte) 1040 { 1041 /* 1042 * The soft-dirty tracker uses #PF-s to catch writes 1043 * to pages, so write-protect the pte as well. See the 1044 * Documentation/admin-guide/mm/soft-dirty.rst for full description 1045 * of how soft-dirty works. 1046 */ 1047 pte_t ptent = *pte; 1048 1049 if (pte_present(ptent)) { 1050 pte_t old_pte; 1051 1052 old_pte = ptep_modify_prot_start(vma, addr, pte); 1053 ptent = pte_wrprotect(old_pte); 1054 ptent = pte_clear_soft_dirty(ptent); 1055 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1056 } else if (is_swap_pte(ptent)) { 1057 ptent = pte_swp_clear_soft_dirty(ptent); 1058 set_pte_at(vma->vm_mm, addr, pte, ptent); 1059 } 1060 } 1061 #else 1062 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1063 unsigned long addr, pte_t *pte) 1064 { 1065 } 1066 #endif 1067 1068 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 1069 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1070 unsigned long addr, pmd_t *pmdp) 1071 { 1072 pmd_t old, pmd = *pmdp; 1073 1074 if (pmd_present(pmd)) { 1075 /* See comment in change_huge_pmd() */ 1076 old = pmdp_invalidate(vma, addr, pmdp); 1077 if (pmd_dirty(old)) 1078 pmd = pmd_mkdirty(pmd); 1079 if (pmd_young(old)) 1080 pmd = pmd_mkyoung(pmd); 1081 1082 pmd = pmd_wrprotect(pmd); 1083 pmd = pmd_clear_soft_dirty(pmd); 1084 1085 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1086 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1087 pmd = pmd_swp_clear_soft_dirty(pmd); 1088 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1089 } 1090 } 1091 #else 1092 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1093 unsigned long addr, pmd_t *pmdp) 1094 { 1095 } 1096 #endif 1097 1098 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1099 unsigned long end, struct mm_walk *walk) 1100 { 1101 struct clear_refs_private *cp = walk->private; 1102 struct vm_area_struct *vma = walk->vma; 1103 pte_t *pte, ptent; 1104 spinlock_t *ptl; 1105 struct page *page; 1106 1107 ptl = pmd_trans_huge_lock(pmd, vma); 1108 if (ptl) { 1109 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1110 clear_soft_dirty_pmd(vma, addr, pmd); 1111 goto out; 1112 } 1113 1114 if (!pmd_present(*pmd)) 1115 goto out; 1116 1117 page = pmd_page(*pmd); 1118 1119 /* Clear accessed and referenced bits. */ 1120 pmdp_test_and_clear_young(vma, addr, pmd); 1121 test_and_clear_page_young(page); 1122 ClearPageReferenced(page); 1123 out: 1124 spin_unlock(ptl); 1125 return 0; 1126 } 1127 1128 if (pmd_trans_unstable(pmd)) 1129 return 0; 1130 1131 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1132 for (; addr != end; pte++, addr += PAGE_SIZE) { 1133 ptent = *pte; 1134 1135 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1136 clear_soft_dirty(vma, addr, pte); 1137 continue; 1138 } 1139 1140 if (!pte_present(ptent)) 1141 continue; 1142 1143 page = vm_normal_page(vma, addr, ptent); 1144 if (!page) 1145 continue; 1146 1147 /* Clear accessed and referenced bits. */ 1148 ptep_test_and_clear_young(vma, addr, pte); 1149 test_and_clear_page_young(page); 1150 ClearPageReferenced(page); 1151 } 1152 pte_unmap_unlock(pte - 1, ptl); 1153 cond_resched(); 1154 return 0; 1155 } 1156 1157 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1158 struct mm_walk *walk) 1159 { 1160 struct clear_refs_private *cp = walk->private; 1161 struct vm_area_struct *vma = walk->vma; 1162 1163 if (vma->vm_flags & VM_PFNMAP) 1164 return 1; 1165 1166 /* 1167 * Writing 1 to /proc/pid/clear_refs affects all pages. 1168 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1169 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1170 * Writing 4 to /proc/pid/clear_refs affects all pages. 1171 */ 1172 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1173 return 1; 1174 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1175 return 1; 1176 return 0; 1177 } 1178 1179 static const struct mm_walk_ops clear_refs_walk_ops = { 1180 .pmd_entry = clear_refs_pte_range, 1181 .test_walk = clear_refs_test_walk, 1182 }; 1183 1184 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1185 size_t count, loff_t *ppos) 1186 { 1187 struct task_struct *task; 1188 char buffer[PROC_NUMBUF]; 1189 struct mm_struct *mm; 1190 struct vm_area_struct *vma; 1191 enum clear_refs_types type; 1192 struct mmu_gather tlb; 1193 int itype; 1194 int rv; 1195 1196 memset(buffer, 0, sizeof(buffer)); 1197 if (count > sizeof(buffer) - 1) 1198 count = sizeof(buffer) - 1; 1199 if (copy_from_user(buffer, buf, count)) 1200 return -EFAULT; 1201 rv = kstrtoint(strstrip(buffer), 10, &itype); 1202 if (rv < 0) 1203 return rv; 1204 type = (enum clear_refs_types)itype; 1205 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1206 return -EINVAL; 1207 1208 task = get_proc_task(file_inode(file)); 1209 if (!task) 1210 return -ESRCH; 1211 mm = get_task_mm(task); 1212 if (mm) { 1213 struct mmu_notifier_range range; 1214 struct clear_refs_private cp = { 1215 .type = type, 1216 }; 1217 1218 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1219 if (mmap_write_lock_killable(mm)) { 1220 count = -EINTR; 1221 goto out_mm; 1222 } 1223 1224 /* 1225 * Writing 5 to /proc/pid/clear_refs resets the peak 1226 * resident set size to this mm's current rss value. 1227 */ 1228 reset_mm_hiwater_rss(mm); 1229 mmap_write_unlock(mm); 1230 goto out_mm; 1231 } 1232 1233 if (mmap_read_lock_killable(mm)) { 1234 count = -EINTR; 1235 goto out_mm; 1236 } 1237 tlb_gather_mmu(&tlb, mm, 0, -1); 1238 if (type == CLEAR_REFS_SOFT_DIRTY) { 1239 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1240 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1241 continue; 1242 mmap_read_unlock(mm); 1243 if (mmap_write_lock_killable(mm)) { 1244 count = -EINTR; 1245 goto out_mm; 1246 } 1247 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1248 vma->vm_flags &= ~VM_SOFTDIRTY; 1249 vma_set_page_prot(vma); 1250 } 1251 mmap_write_downgrade(mm); 1252 break; 1253 } 1254 1255 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1256 0, NULL, mm, 0, -1UL); 1257 mmu_notifier_invalidate_range_start(&range); 1258 } 1259 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1260 &cp); 1261 if (type == CLEAR_REFS_SOFT_DIRTY) 1262 mmu_notifier_invalidate_range_end(&range); 1263 tlb_finish_mmu(&tlb, 0, -1); 1264 mmap_read_unlock(mm); 1265 out_mm: 1266 mmput(mm); 1267 } 1268 put_task_struct(task); 1269 1270 return count; 1271 } 1272 1273 const struct file_operations proc_clear_refs_operations = { 1274 .write = clear_refs_write, 1275 .llseek = noop_llseek, 1276 }; 1277 1278 typedef struct { 1279 u64 pme; 1280 } pagemap_entry_t; 1281 1282 struct pagemapread { 1283 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1284 pagemap_entry_t *buffer; 1285 bool show_pfn; 1286 }; 1287 1288 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1289 #define PAGEMAP_WALK_MASK (PMD_MASK) 1290 1291 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1292 #define PM_PFRAME_BITS 55 1293 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1294 #define PM_SOFT_DIRTY BIT_ULL(55) 1295 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1296 #define PM_FILE BIT_ULL(61) 1297 #define PM_SWAP BIT_ULL(62) 1298 #define PM_PRESENT BIT_ULL(63) 1299 1300 #define PM_END_OF_BUFFER 1 1301 1302 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1303 { 1304 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1305 } 1306 1307 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1308 struct pagemapread *pm) 1309 { 1310 pm->buffer[pm->pos++] = *pme; 1311 if (pm->pos >= pm->len) 1312 return PM_END_OF_BUFFER; 1313 return 0; 1314 } 1315 1316 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1317 __always_unused int depth, struct mm_walk *walk) 1318 { 1319 struct pagemapread *pm = walk->private; 1320 unsigned long addr = start; 1321 int err = 0; 1322 1323 while (addr < end) { 1324 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1325 pagemap_entry_t pme = make_pme(0, 0); 1326 /* End of address space hole, which we mark as non-present. */ 1327 unsigned long hole_end; 1328 1329 if (vma) 1330 hole_end = min(end, vma->vm_start); 1331 else 1332 hole_end = end; 1333 1334 for (; addr < hole_end; addr += PAGE_SIZE) { 1335 err = add_to_pagemap(addr, &pme, pm); 1336 if (err) 1337 goto out; 1338 } 1339 1340 if (!vma) 1341 break; 1342 1343 /* Addresses in the VMA. */ 1344 if (vma->vm_flags & VM_SOFTDIRTY) 1345 pme = make_pme(0, PM_SOFT_DIRTY); 1346 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1347 err = add_to_pagemap(addr, &pme, pm); 1348 if (err) 1349 goto out; 1350 } 1351 } 1352 out: 1353 return err; 1354 } 1355 1356 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1357 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1358 { 1359 u64 frame = 0, flags = 0; 1360 struct page *page = NULL; 1361 1362 if (pte_present(pte)) { 1363 if (pm->show_pfn) 1364 frame = pte_pfn(pte); 1365 flags |= PM_PRESENT; 1366 page = vm_normal_page(vma, addr, pte); 1367 if (pte_soft_dirty(pte)) 1368 flags |= PM_SOFT_DIRTY; 1369 } else if (is_swap_pte(pte)) { 1370 swp_entry_t entry; 1371 if (pte_swp_soft_dirty(pte)) 1372 flags |= PM_SOFT_DIRTY; 1373 entry = pte_to_swp_entry(pte); 1374 if (pm->show_pfn) 1375 frame = swp_type(entry) | 1376 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1377 flags |= PM_SWAP; 1378 if (is_migration_entry(entry)) 1379 page = migration_entry_to_page(entry); 1380 1381 if (is_device_private_entry(entry)) 1382 page = device_private_entry_to_page(entry); 1383 } 1384 1385 if (page && !PageAnon(page)) 1386 flags |= PM_FILE; 1387 if (page && page_mapcount(page) == 1) 1388 flags |= PM_MMAP_EXCLUSIVE; 1389 if (vma->vm_flags & VM_SOFTDIRTY) 1390 flags |= PM_SOFT_DIRTY; 1391 1392 return make_pme(frame, flags); 1393 } 1394 1395 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1396 struct mm_walk *walk) 1397 { 1398 struct vm_area_struct *vma = walk->vma; 1399 struct pagemapread *pm = walk->private; 1400 spinlock_t *ptl; 1401 pte_t *pte, *orig_pte; 1402 int err = 0; 1403 1404 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1405 ptl = pmd_trans_huge_lock(pmdp, vma); 1406 if (ptl) { 1407 u64 flags = 0, frame = 0; 1408 pmd_t pmd = *pmdp; 1409 struct page *page = NULL; 1410 1411 if (vma->vm_flags & VM_SOFTDIRTY) 1412 flags |= PM_SOFT_DIRTY; 1413 1414 if (pmd_present(pmd)) { 1415 page = pmd_page(pmd); 1416 1417 flags |= PM_PRESENT; 1418 if (pmd_soft_dirty(pmd)) 1419 flags |= PM_SOFT_DIRTY; 1420 if (pm->show_pfn) 1421 frame = pmd_pfn(pmd) + 1422 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1423 } 1424 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1425 else if (is_swap_pmd(pmd)) { 1426 swp_entry_t entry = pmd_to_swp_entry(pmd); 1427 unsigned long offset; 1428 1429 if (pm->show_pfn) { 1430 offset = swp_offset(entry) + 1431 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1432 frame = swp_type(entry) | 1433 (offset << MAX_SWAPFILES_SHIFT); 1434 } 1435 flags |= PM_SWAP; 1436 if (pmd_swp_soft_dirty(pmd)) 1437 flags |= PM_SOFT_DIRTY; 1438 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1439 page = migration_entry_to_page(entry); 1440 } 1441 #endif 1442 1443 if (page && page_mapcount(page) == 1) 1444 flags |= PM_MMAP_EXCLUSIVE; 1445 1446 for (; addr != end; addr += PAGE_SIZE) { 1447 pagemap_entry_t pme = make_pme(frame, flags); 1448 1449 err = add_to_pagemap(addr, &pme, pm); 1450 if (err) 1451 break; 1452 if (pm->show_pfn) { 1453 if (flags & PM_PRESENT) 1454 frame++; 1455 else if (flags & PM_SWAP) 1456 frame += (1 << MAX_SWAPFILES_SHIFT); 1457 } 1458 } 1459 spin_unlock(ptl); 1460 return err; 1461 } 1462 1463 if (pmd_trans_unstable(pmdp)) 1464 return 0; 1465 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1466 1467 /* 1468 * We can assume that @vma always points to a valid one and @end never 1469 * goes beyond vma->vm_end. 1470 */ 1471 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1472 for (; addr < end; pte++, addr += PAGE_SIZE) { 1473 pagemap_entry_t pme; 1474 1475 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1476 err = add_to_pagemap(addr, &pme, pm); 1477 if (err) 1478 break; 1479 } 1480 pte_unmap_unlock(orig_pte, ptl); 1481 1482 cond_resched(); 1483 1484 return err; 1485 } 1486 1487 #ifdef CONFIG_HUGETLB_PAGE 1488 /* This function walks within one hugetlb entry in the single call */ 1489 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1490 unsigned long addr, unsigned long end, 1491 struct mm_walk *walk) 1492 { 1493 struct pagemapread *pm = walk->private; 1494 struct vm_area_struct *vma = walk->vma; 1495 u64 flags = 0, frame = 0; 1496 int err = 0; 1497 pte_t pte; 1498 1499 if (vma->vm_flags & VM_SOFTDIRTY) 1500 flags |= PM_SOFT_DIRTY; 1501 1502 pte = huge_ptep_get(ptep); 1503 if (pte_present(pte)) { 1504 struct page *page = pte_page(pte); 1505 1506 if (!PageAnon(page)) 1507 flags |= PM_FILE; 1508 1509 if (page_mapcount(page) == 1) 1510 flags |= PM_MMAP_EXCLUSIVE; 1511 1512 flags |= PM_PRESENT; 1513 if (pm->show_pfn) 1514 frame = pte_pfn(pte) + 1515 ((addr & ~hmask) >> PAGE_SHIFT); 1516 } 1517 1518 for (; addr != end; addr += PAGE_SIZE) { 1519 pagemap_entry_t pme = make_pme(frame, flags); 1520 1521 err = add_to_pagemap(addr, &pme, pm); 1522 if (err) 1523 return err; 1524 if (pm->show_pfn && (flags & PM_PRESENT)) 1525 frame++; 1526 } 1527 1528 cond_resched(); 1529 1530 return err; 1531 } 1532 #else 1533 #define pagemap_hugetlb_range NULL 1534 #endif /* HUGETLB_PAGE */ 1535 1536 static const struct mm_walk_ops pagemap_ops = { 1537 .pmd_entry = pagemap_pmd_range, 1538 .pte_hole = pagemap_pte_hole, 1539 .hugetlb_entry = pagemap_hugetlb_range, 1540 }; 1541 1542 /* 1543 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1544 * 1545 * For each page in the address space, this file contains one 64-bit entry 1546 * consisting of the following: 1547 * 1548 * Bits 0-54 page frame number (PFN) if present 1549 * Bits 0-4 swap type if swapped 1550 * Bits 5-54 swap offset if swapped 1551 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1552 * Bit 56 page exclusively mapped 1553 * Bits 57-60 zero 1554 * Bit 61 page is file-page or shared-anon 1555 * Bit 62 page swapped 1556 * Bit 63 page present 1557 * 1558 * If the page is not present but in swap, then the PFN contains an 1559 * encoding of the swap file number and the page's offset into the 1560 * swap. Unmapped pages return a null PFN. This allows determining 1561 * precisely which pages are mapped (or in swap) and comparing mapped 1562 * pages between processes. 1563 * 1564 * Efficient users of this interface will use /proc/pid/maps to 1565 * determine which areas of memory are actually mapped and llseek to 1566 * skip over unmapped regions. 1567 */ 1568 static ssize_t pagemap_read(struct file *file, char __user *buf, 1569 size_t count, loff_t *ppos) 1570 { 1571 struct mm_struct *mm = file->private_data; 1572 struct pagemapread pm; 1573 unsigned long src; 1574 unsigned long svpfn; 1575 unsigned long start_vaddr; 1576 unsigned long end_vaddr; 1577 int ret = 0, copied = 0; 1578 1579 if (!mm || !mmget_not_zero(mm)) 1580 goto out; 1581 1582 ret = -EINVAL; 1583 /* file position must be aligned */ 1584 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1585 goto out_mm; 1586 1587 ret = 0; 1588 if (!count) 1589 goto out_mm; 1590 1591 /* do not disclose physical addresses: attack vector */ 1592 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1593 1594 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1595 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1596 ret = -ENOMEM; 1597 if (!pm.buffer) 1598 goto out_mm; 1599 1600 src = *ppos; 1601 svpfn = src / PM_ENTRY_BYTES; 1602 start_vaddr = svpfn << PAGE_SHIFT; 1603 end_vaddr = mm->task_size; 1604 1605 /* watch out for wraparound */ 1606 if (svpfn > mm->task_size >> PAGE_SHIFT) 1607 start_vaddr = end_vaddr; 1608 1609 /* 1610 * The odds are that this will stop walking way 1611 * before end_vaddr, because the length of the 1612 * user buffer is tracked in "pm", and the walk 1613 * will stop when we hit the end of the buffer. 1614 */ 1615 ret = 0; 1616 while (count && (start_vaddr < end_vaddr)) { 1617 int len; 1618 unsigned long end; 1619 1620 pm.pos = 0; 1621 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1622 /* overflow ? */ 1623 if (end < start_vaddr || end > end_vaddr) 1624 end = end_vaddr; 1625 ret = mmap_read_lock_killable(mm); 1626 if (ret) 1627 goto out_free; 1628 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1629 mmap_read_unlock(mm); 1630 start_vaddr = end; 1631 1632 len = min(count, PM_ENTRY_BYTES * pm.pos); 1633 if (copy_to_user(buf, pm.buffer, len)) { 1634 ret = -EFAULT; 1635 goto out_free; 1636 } 1637 copied += len; 1638 buf += len; 1639 count -= len; 1640 } 1641 *ppos += copied; 1642 if (!ret || ret == PM_END_OF_BUFFER) 1643 ret = copied; 1644 1645 out_free: 1646 kfree(pm.buffer); 1647 out_mm: 1648 mmput(mm); 1649 out: 1650 return ret; 1651 } 1652 1653 static int pagemap_open(struct inode *inode, struct file *file) 1654 { 1655 struct mm_struct *mm; 1656 1657 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1658 if (IS_ERR(mm)) 1659 return PTR_ERR(mm); 1660 file->private_data = mm; 1661 return 0; 1662 } 1663 1664 static int pagemap_release(struct inode *inode, struct file *file) 1665 { 1666 struct mm_struct *mm = file->private_data; 1667 1668 if (mm) 1669 mmdrop(mm); 1670 return 0; 1671 } 1672 1673 const struct file_operations proc_pagemap_operations = { 1674 .llseek = mem_lseek, /* borrow this */ 1675 .read = pagemap_read, 1676 .open = pagemap_open, 1677 .release = pagemap_release, 1678 }; 1679 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1680 1681 #ifdef CONFIG_NUMA 1682 1683 struct numa_maps { 1684 unsigned long pages; 1685 unsigned long anon; 1686 unsigned long active; 1687 unsigned long writeback; 1688 unsigned long mapcount_max; 1689 unsigned long dirty; 1690 unsigned long swapcache; 1691 unsigned long node[MAX_NUMNODES]; 1692 }; 1693 1694 struct numa_maps_private { 1695 struct proc_maps_private proc_maps; 1696 struct numa_maps md; 1697 }; 1698 1699 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1700 unsigned long nr_pages) 1701 { 1702 int count = page_mapcount(page); 1703 1704 md->pages += nr_pages; 1705 if (pte_dirty || PageDirty(page)) 1706 md->dirty += nr_pages; 1707 1708 if (PageSwapCache(page)) 1709 md->swapcache += nr_pages; 1710 1711 if (PageActive(page) || PageUnevictable(page)) 1712 md->active += nr_pages; 1713 1714 if (PageWriteback(page)) 1715 md->writeback += nr_pages; 1716 1717 if (PageAnon(page)) 1718 md->anon += nr_pages; 1719 1720 if (count > md->mapcount_max) 1721 md->mapcount_max = count; 1722 1723 md->node[page_to_nid(page)] += nr_pages; 1724 } 1725 1726 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1727 unsigned long addr) 1728 { 1729 struct page *page; 1730 int nid; 1731 1732 if (!pte_present(pte)) 1733 return NULL; 1734 1735 page = vm_normal_page(vma, addr, pte); 1736 if (!page) 1737 return NULL; 1738 1739 if (PageReserved(page)) 1740 return NULL; 1741 1742 nid = page_to_nid(page); 1743 if (!node_isset(nid, node_states[N_MEMORY])) 1744 return NULL; 1745 1746 return page; 1747 } 1748 1749 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1750 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1751 struct vm_area_struct *vma, 1752 unsigned long addr) 1753 { 1754 struct page *page; 1755 int nid; 1756 1757 if (!pmd_present(pmd)) 1758 return NULL; 1759 1760 page = vm_normal_page_pmd(vma, addr, pmd); 1761 if (!page) 1762 return NULL; 1763 1764 if (PageReserved(page)) 1765 return NULL; 1766 1767 nid = page_to_nid(page); 1768 if (!node_isset(nid, node_states[N_MEMORY])) 1769 return NULL; 1770 1771 return page; 1772 } 1773 #endif 1774 1775 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1776 unsigned long end, struct mm_walk *walk) 1777 { 1778 struct numa_maps *md = walk->private; 1779 struct vm_area_struct *vma = walk->vma; 1780 spinlock_t *ptl; 1781 pte_t *orig_pte; 1782 pte_t *pte; 1783 1784 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1785 ptl = pmd_trans_huge_lock(pmd, vma); 1786 if (ptl) { 1787 struct page *page; 1788 1789 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1790 if (page) 1791 gather_stats(page, md, pmd_dirty(*pmd), 1792 HPAGE_PMD_SIZE/PAGE_SIZE); 1793 spin_unlock(ptl); 1794 return 0; 1795 } 1796 1797 if (pmd_trans_unstable(pmd)) 1798 return 0; 1799 #endif 1800 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1801 do { 1802 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1803 if (!page) 1804 continue; 1805 gather_stats(page, md, pte_dirty(*pte), 1); 1806 1807 } while (pte++, addr += PAGE_SIZE, addr != end); 1808 pte_unmap_unlock(orig_pte, ptl); 1809 cond_resched(); 1810 return 0; 1811 } 1812 #ifdef CONFIG_HUGETLB_PAGE 1813 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1814 unsigned long addr, unsigned long end, struct mm_walk *walk) 1815 { 1816 pte_t huge_pte = huge_ptep_get(pte); 1817 struct numa_maps *md; 1818 struct page *page; 1819 1820 if (!pte_present(huge_pte)) 1821 return 0; 1822 1823 page = pte_page(huge_pte); 1824 if (!page) 1825 return 0; 1826 1827 md = walk->private; 1828 gather_stats(page, md, pte_dirty(huge_pte), 1); 1829 return 0; 1830 } 1831 1832 #else 1833 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1834 unsigned long addr, unsigned long end, struct mm_walk *walk) 1835 { 1836 return 0; 1837 } 1838 #endif 1839 1840 static const struct mm_walk_ops show_numa_ops = { 1841 .hugetlb_entry = gather_hugetlb_stats, 1842 .pmd_entry = gather_pte_stats, 1843 }; 1844 1845 /* 1846 * Display pages allocated per node and memory policy via /proc. 1847 */ 1848 static int show_numa_map(struct seq_file *m, void *v) 1849 { 1850 struct numa_maps_private *numa_priv = m->private; 1851 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1852 struct vm_area_struct *vma = v; 1853 struct numa_maps *md = &numa_priv->md; 1854 struct file *file = vma->vm_file; 1855 struct mm_struct *mm = vma->vm_mm; 1856 struct mempolicy *pol; 1857 char buffer[64]; 1858 int nid; 1859 1860 if (!mm) 1861 return 0; 1862 1863 /* Ensure we start with an empty set of numa_maps statistics. */ 1864 memset(md, 0, sizeof(*md)); 1865 1866 pol = __get_vma_policy(vma, vma->vm_start); 1867 if (pol) { 1868 mpol_to_str(buffer, sizeof(buffer), pol); 1869 mpol_cond_put(pol); 1870 } else { 1871 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1872 } 1873 1874 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1875 1876 if (file) { 1877 seq_puts(m, " file="); 1878 seq_file_path(m, file, "\n\t= "); 1879 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1880 seq_puts(m, " heap"); 1881 } else if (is_stack(vma)) { 1882 seq_puts(m, " stack"); 1883 } 1884 1885 if (is_vm_hugetlb_page(vma)) 1886 seq_puts(m, " huge"); 1887 1888 /* mmap_lock is held by m_start */ 1889 walk_page_vma(vma, &show_numa_ops, md); 1890 1891 if (!md->pages) 1892 goto out; 1893 1894 if (md->anon) 1895 seq_printf(m, " anon=%lu", md->anon); 1896 1897 if (md->dirty) 1898 seq_printf(m, " dirty=%lu", md->dirty); 1899 1900 if (md->pages != md->anon && md->pages != md->dirty) 1901 seq_printf(m, " mapped=%lu", md->pages); 1902 1903 if (md->mapcount_max > 1) 1904 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1905 1906 if (md->swapcache) 1907 seq_printf(m, " swapcache=%lu", md->swapcache); 1908 1909 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1910 seq_printf(m, " active=%lu", md->active); 1911 1912 if (md->writeback) 1913 seq_printf(m, " writeback=%lu", md->writeback); 1914 1915 for_each_node_state(nid, N_MEMORY) 1916 if (md->node[nid]) 1917 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1918 1919 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1920 out: 1921 seq_putc(m, '\n'); 1922 return 0; 1923 } 1924 1925 static const struct seq_operations proc_pid_numa_maps_op = { 1926 .start = m_start, 1927 .next = m_next, 1928 .stop = m_stop, 1929 .show = show_numa_map, 1930 }; 1931 1932 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1933 { 1934 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1935 sizeof(struct numa_maps_private)); 1936 } 1937 1938 const struct file_operations proc_pid_numa_maps_operations = { 1939 .open = pid_numa_maps_open, 1940 .read = seq_read, 1941 .llseek = seq_lseek, 1942 .release = proc_map_release, 1943 }; 1944 1945 #endif /* CONFIG_NUMA */ 1946