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_ARM64_MTE 657 [ilog2(VM_MTE)] = "mt", 658 [ilog2(VM_MTE_ALLOWED)] = "", 659 #endif 660 #ifdef CONFIG_ARCH_HAS_PKEYS 661 /* These come out via ProtectionKey: */ 662 [ilog2(VM_PKEY_BIT0)] = "", 663 [ilog2(VM_PKEY_BIT1)] = "", 664 [ilog2(VM_PKEY_BIT2)] = "", 665 [ilog2(VM_PKEY_BIT3)] = "", 666 #if VM_PKEY_BIT4 667 [ilog2(VM_PKEY_BIT4)] = "", 668 #endif 669 #endif /* CONFIG_ARCH_HAS_PKEYS */ 670 }; 671 size_t i; 672 673 seq_puts(m, "VmFlags: "); 674 for (i = 0; i < BITS_PER_LONG; i++) { 675 if (!mnemonics[i][0]) 676 continue; 677 if (vma->vm_flags & (1UL << i)) { 678 seq_putc(m, mnemonics[i][0]); 679 seq_putc(m, mnemonics[i][1]); 680 seq_putc(m, ' '); 681 } 682 } 683 seq_putc(m, '\n'); 684 } 685 686 #ifdef CONFIG_HUGETLB_PAGE 687 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 688 unsigned long addr, unsigned long end, 689 struct mm_walk *walk) 690 { 691 struct mem_size_stats *mss = walk->private; 692 struct vm_area_struct *vma = walk->vma; 693 struct page *page = NULL; 694 695 if (pte_present(*pte)) { 696 page = vm_normal_page(vma, addr, *pte); 697 } else if (is_swap_pte(*pte)) { 698 swp_entry_t swpent = pte_to_swp_entry(*pte); 699 700 if (is_migration_entry(swpent)) 701 page = migration_entry_to_page(swpent); 702 else if (is_device_private_entry(swpent)) 703 page = device_private_entry_to_page(swpent); 704 } 705 if (page) { 706 int mapcount = page_mapcount(page); 707 708 if (mapcount >= 2) 709 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 710 else 711 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 712 } 713 return 0; 714 } 715 #else 716 #define smaps_hugetlb_range NULL 717 #endif /* HUGETLB_PAGE */ 718 719 static const struct mm_walk_ops smaps_walk_ops = { 720 .pmd_entry = smaps_pte_range, 721 .hugetlb_entry = smaps_hugetlb_range, 722 }; 723 724 static const struct mm_walk_ops smaps_shmem_walk_ops = { 725 .pmd_entry = smaps_pte_range, 726 .hugetlb_entry = smaps_hugetlb_range, 727 .pte_hole = smaps_pte_hole, 728 }; 729 730 static void smap_gather_stats(struct vm_area_struct *vma, 731 struct mem_size_stats *mss) 732 { 733 #ifdef CONFIG_SHMEM 734 /* In case of smaps_rollup, reset the value from previous vma */ 735 mss->check_shmem_swap = false; 736 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 737 /* 738 * For shared or readonly shmem mappings we know that all 739 * swapped out pages belong to the shmem object, and we can 740 * obtain the swap value much more efficiently. For private 741 * writable mappings, we might have COW pages that are 742 * not affected by the parent swapped out pages of the shmem 743 * object, so we have to distinguish them during the page walk. 744 * Unless we know that the shmem object (or the part mapped by 745 * our VMA) has no swapped out pages at all. 746 */ 747 unsigned long shmem_swapped = shmem_swap_usage(vma); 748 749 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 750 !(vma->vm_flags & VM_WRITE)) { 751 mss->swap += shmem_swapped; 752 } else { 753 mss->check_shmem_swap = true; 754 walk_page_vma(vma, &smaps_shmem_walk_ops, mss); 755 return; 756 } 757 } 758 #endif 759 /* mmap_lock is held in m_start */ 760 walk_page_vma(vma, &smaps_walk_ops, mss); 761 } 762 763 #define SEQ_PUT_DEC(str, val) \ 764 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 765 766 /* Show the contents common for smaps and smaps_rollup */ 767 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 768 bool rollup_mode) 769 { 770 SEQ_PUT_DEC("Rss: ", mss->resident); 771 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 772 if (rollup_mode) { 773 /* 774 * These are meaningful only for smaps_rollup, otherwise two of 775 * them are zero, and the other one is the same as Pss. 776 */ 777 SEQ_PUT_DEC(" kB\nPss_Anon: ", 778 mss->pss_anon >> PSS_SHIFT); 779 SEQ_PUT_DEC(" kB\nPss_File: ", 780 mss->pss_file >> PSS_SHIFT); 781 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 782 mss->pss_shmem >> PSS_SHIFT); 783 } 784 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 785 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 786 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 787 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 788 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 789 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 790 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 791 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 792 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 793 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 794 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 795 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 796 mss->private_hugetlb >> 10, 7); 797 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 798 SEQ_PUT_DEC(" kB\nSwapPss: ", 799 mss->swap_pss >> PSS_SHIFT); 800 SEQ_PUT_DEC(" kB\nLocked: ", 801 mss->pss_locked >> PSS_SHIFT); 802 seq_puts(m, " kB\n"); 803 } 804 805 static int show_smap(struct seq_file *m, void *v) 806 { 807 struct vm_area_struct *vma = v; 808 struct mem_size_stats mss; 809 810 memset(&mss, 0, sizeof(mss)); 811 812 smap_gather_stats(vma, &mss); 813 814 show_map_vma(m, vma); 815 816 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 817 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 818 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 819 seq_puts(m, " kB\n"); 820 821 __show_smap(m, &mss, false); 822 823 seq_printf(m, "THPeligible: %d\n", 824 transparent_hugepage_enabled(vma)); 825 826 if (arch_pkeys_enabled()) 827 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 828 show_smap_vma_flags(m, vma); 829 830 return 0; 831 } 832 833 static int show_smaps_rollup(struct seq_file *m, void *v) 834 { 835 struct proc_maps_private *priv = m->private; 836 struct mem_size_stats mss; 837 struct mm_struct *mm; 838 struct vm_area_struct *vma; 839 unsigned long last_vma_end = 0; 840 int ret = 0; 841 842 priv->task = get_proc_task(priv->inode); 843 if (!priv->task) 844 return -ESRCH; 845 846 mm = priv->mm; 847 if (!mm || !mmget_not_zero(mm)) { 848 ret = -ESRCH; 849 goto out_put_task; 850 } 851 852 memset(&mss, 0, sizeof(mss)); 853 854 ret = mmap_read_lock_killable(mm); 855 if (ret) 856 goto out_put_mm; 857 858 hold_task_mempolicy(priv); 859 860 for (vma = priv->mm->mmap; vma; vma = vma->vm_next) { 861 smap_gather_stats(vma, &mss); 862 last_vma_end = vma->vm_end; 863 } 864 865 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 866 last_vma_end, 0, 0, 0, 0); 867 seq_pad(m, ' '); 868 seq_puts(m, "[rollup]\n"); 869 870 __show_smap(m, &mss, true); 871 872 release_task_mempolicy(priv); 873 mmap_read_unlock(mm); 874 875 out_put_mm: 876 mmput(mm); 877 out_put_task: 878 put_task_struct(priv->task); 879 priv->task = NULL; 880 881 return ret; 882 } 883 #undef SEQ_PUT_DEC 884 885 static const struct seq_operations proc_pid_smaps_op = { 886 .start = m_start, 887 .next = m_next, 888 .stop = m_stop, 889 .show = show_smap 890 }; 891 892 static int pid_smaps_open(struct inode *inode, struct file *file) 893 { 894 return do_maps_open(inode, file, &proc_pid_smaps_op); 895 } 896 897 static int smaps_rollup_open(struct inode *inode, struct file *file) 898 { 899 int ret; 900 struct proc_maps_private *priv; 901 902 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 903 if (!priv) 904 return -ENOMEM; 905 906 ret = single_open(file, show_smaps_rollup, priv); 907 if (ret) 908 goto out_free; 909 910 priv->inode = inode; 911 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 912 if (IS_ERR(priv->mm)) { 913 ret = PTR_ERR(priv->mm); 914 915 single_release(inode, file); 916 goto out_free; 917 } 918 919 return 0; 920 921 out_free: 922 kfree(priv); 923 return ret; 924 } 925 926 static int smaps_rollup_release(struct inode *inode, struct file *file) 927 { 928 struct seq_file *seq = file->private_data; 929 struct proc_maps_private *priv = seq->private; 930 931 if (priv->mm) 932 mmdrop(priv->mm); 933 934 kfree(priv); 935 return single_release(inode, file); 936 } 937 938 const struct file_operations proc_pid_smaps_operations = { 939 .open = pid_smaps_open, 940 .read = seq_read, 941 .llseek = seq_lseek, 942 .release = proc_map_release, 943 }; 944 945 const struct file_operations proc_pid_smaps_rollup_operations = { 946 .open = smaps_rollup_open, 947 .read = seq_read, 948 .llseek = seq_lseek, 949 .release = smaps_rollup_release, 950 }; 951 952 enum clear_refs_types { 953 CLEAR_REFS_ALL = 1, 954 CLEAR_REFS_ANON, 955 CLEAR_REFS_MAPPED, 956 CLEAR_REFS_SOFT_DIRTY, 957 CLEAR_REFS_MM_HIWATER_RSS, 958 CLEAR_REFS_LAST, 959 }; 960 961 struct clear_refs_private { 962 enum clear_refs_types type; 963 }; 964 965 #ifdef CONFIG_MEM_SOFT_DIRTY 966 static inline void clear_soft_dirty(struct vm_area_struct *vma, 967 unsigned long addr, pte_t *pte) 968 { 969 /* 970 * The soft-dirty tracker uses #PF-s to catch writes 971 * to pages, so write-protect the pte as well. See the 972 * Documentation/admin-guide/mm/soft-dirty.rst for full description 973 * of how soft-dirty works. 974 */ 975 pte_t ptent = *pte; 976 977 if (pte_present(ptent)) { 978 pte_t old_pte; 979 980 old_pte = ptep_modify_prot_start(vma, addr, pte); 981 ptent = pte_wrprotect(old_pte); 982 ptent = pte_clear_soft_dirty(ptent); 983 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 984 } else if (is_swap_pte(ptent)) { 985 ptent = pte_swp_clear_soft_dirty(ptent); 986 set_pte_at(vma->vm_mm, addr, pte, ptent); 987 } 988 } 989 #else 990 static inline void clear_soft_dirty(struct vm_area_struct *vma, 991 unsigned long addr, pte_t *pte) 992 { 993 } 994 #endif 995 996 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 997 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 998 unsigned long addr, pmd_t *pmdp) 999 { 1000 pmd_t old, pmd = *pmdp; 1001 1002 if (pmd_present(pmd)) { 1003 /* See comment in change_huge_pmd() */ 1004 old = pmdp_invalidate(vma, addr, pmdp); 1005 if (pmd_dirty(old)) 1006 pmd = pmd_mkdirty(pmd); 1007 if (pmd_young(old)) 1008 pmd = pmd_mkyoung(pmd); 1009 1010 pmd = pmd_wrprotect(pmd); 1011 pmd = pmd_clear_soft_dirty(pmd); 1012 1013 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1014 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1015 pmd = pmd_swp_clear_soft_dirty(pmd); 1016 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1017 } 1018 } 1019 #else 1020 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1021 unsigned long addr, pmd_t *pmdp) 1022 { 1023 } 1024 #endif 1025 1026 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1027 unsigned long end, struct mm_walk *walk) 1028 { 1029 struct clear_refs_private *cp = walk->private; 1030 struct vm_area_struct *vma = walk->vma; 1031 pte_t *pte, ptent; 1032 spinlock_t *ptl; 1033 struct page *page; 1034 1035 ptl = pmd_trans_huge_lock(pmd, vma); 1036 if (ptl) { 1037 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1038 clear_soft_dirty_pmd(vma, addr, pmd); 1039 goto out; 1040 } 1041 1042 if (!pmd_present(*pmd)) 1043 goto out; 1044 1045 page = pmd_page(*pmd); 1046 1047 /* Clear accessed and referenced bits. */ 1048 pmdp_test_and_clear_young(vma, addr, pmd); 1049 test_and_clear_page_young(page); 1050 ClearPageReferenced(page); 1051 out: 1052 spin_unlock(ptl); 1053 return 0; 1054 } 1055 1056 if (pmd_trans_unstable(pmd)) 1057 return 0; 1058 1059 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1060 for (; addr != end; pte++, addr += PAGE_SIZE) { 1061 ptent = *pte; 1062 1063 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1064 clear_soft_dirty(vma, addr, pte); 1065 continue; 1066 } 1067 1068 if (!pte_present(ptent)) 1069 continue; 1070 1071 page = vm_normal_page(vma, addr, ptent); 1072 if (!page) 1073 continue; 1074 1075 /* Clear accessed and referenced bits. */ 1076 ptep_test_and_clear_young(vma, addr, pte); 1077 test_and_clear_page_young(page); 1078 ClearPageReferenced(page); 1079 } 1080 pte_unmap_unlock(pte - 1, ptl); 1081 cond_resched(); 1082 return 0; 1083 } 1084 1085 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1086 struct mm_walk *walk) 1087 { 1088 struct clear_refs_private *cp = walk->private; 1089 struct vm_area_struct *vma = walk->vma; 1090 1091 if (vma->vm_flags & VM_PFNMAP) 1092 return 1; 1093 1094 /* 1095 * Writing 1 to /proc/pid/clear_refs affects all pages. 1096 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1097 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1098 * Writing 4 to /proc/pid/clear_refs affects all pages. 1099 */ 1100 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1101 return 1; 1102 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1103 return 1; 1104 return 0; 1105 } 1106 1107 static const struct mm_walk_ops clear_refs_walk_ops = { 1108 .pmd_entry = clear_refs_pte_range, 1109 .test_walk = clear_refs_test_walk, 1110 }; 1111 1112 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1113 size_t count, loff_t *ppos) 1114 { 1115 struct task_struct *task; 1116 char buffer[PROC_NUMBUF]; 1117 struct mm_struct *mm; 1118 struct vm_area_struct *vma; 1119 enum clear_refs_types type; 1120 struct mmu_gather tlb; 1121 int itype; 1122 int rv; 1123 1124 memset(buffer, 0, sizeof(buffer)); 1125 if (count > sizeof(buffer) - 1) 1126 count = sizeof(buffer) - 1; 1127 if (copy_from_user(buffer, buf, count)) 1128 return -EFAULT; 1129 rv = kstrtoint(strstrip(buffer), 10, &itype); 1130 if (rv < 0) 1131 return rv; 1132 type = (enum clear_refs_types)itype; 1133 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1134 return -EINVAL; 1135 1136 task = get_proc_task(file_inode(file)); 1137 if (!task) 1138 return -ESRCH; 1139 mm = get_task_mm(task); 1140 if (mm) { 1141 struct mmu_notifier_range range; 1142 struct clear_refs_private cp = { 1143 .type = type, 1144 }; 1145 1146 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1147 if (mmap_write_lock_killable(mm)) { 1148 count = -EINTR; 1149 goto out_mm; 1150 } 1151 1152 /* 1153 * Writing 5 to /proc/pid/clear_refs resets the peak 1154 * resident set size to this mm's current rss value. 1155 */ 1156 reset_mm_hiwater_rss(mm); 1157 mmap_write_unlock(mm); 1158 goto out_mm; 1159 } 1160 1161 if (mmap_read_lock_killable(mm)) { 1162 count = -EINTR; 1163 goto out_mm; 1164 } 1165 tlb_gather_mmu(&tlb, mm, 0, -1); 1166 if (type == CLEAR_REFS_SOFT_DIRTY) { 1167 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1168 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1169 continue; 1170 mmap_read_unlock(mm); 1171 if (mmap_write_lock_killable(mm)) { 1172 count = -EINTR; 1173 goto out_mm; 1174 } 1175 /* 1176 * Avoid to modify vma->vm_flags 1177 * without locked ops while the 1178 * coredump reads the vm_flags. 1179 */ 1180 if (!mmget_still_valid(mm)) { 1181 /* 1182 * Silently return "count" 1183 * like if get_task_mm() 1184 * failed. FIXME: should this 1185 * function have returned 1186 * -ESRCH if get_task_mm() 1187 * failed like if 1188 * get_proc_task() fails? 1189 */ 1190 mmap_write_unlock(mm); 1191 goto out_mm; 1192 } 1193 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1194 vma->vm_flags &= ~VM_SOFTDIRTY; 1195 vma_set_page_prot(vma); 1196 } 1197 mmap_write_downgrade(mm); 1198 break; 1199 } 1200 1201 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1202 0, NULL, mm, 0, -1UL); 1203 mmu_notifier_invalidate_range_start(&range); 1204 } 1205 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1206 &cp); 1207 if (type == CLEAR_REFS_SOFT_DIRTY) 1208 mmu_notifier_invalidate_range_end(&range); 1209 tlb_finish_mmu(&tlb, 0, -1); 1210 mmap_read_unlock(mm); 1211 out_mm: 1212 mmput(mm); 1213 } 1214 put_task_struct(task); 1215 1216 return count; 1217 } 1218 1219 const struct file_operations proc_clear_refs_operations = { 1220 .write = clear_refs_write, 1221 .llseek = noop_llseek, 1222 }; 1223 1224 typedef struct { 1225 u64 pme; 1226 } pagemap_entry_t; 1227 1228 struct pagemapread { 1229 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1230 pagemap_entry_t *buffer; 1231 bool show_pfn; 1232 }; 1233 1234 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1235 #define PAGEMAP_WALK_MASK (PMD_MASK) 1236 1237 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1238 #define PM_PFRAME_BITS 55 1239 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1240 #define PM_SOFT_DIRTY BIT_ULL(55) 1241 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1242 #define PM_FILE BIT_ULL(61) 1243 #define PM_SWAP BIT_ULL(62) 1244 #define PM_PRESENT BIT_ULL(63) 1245 1246 #define PM_END_OF_BUFFER 1 1247 1248 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1249 { 1250 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1251 } 1252 1253 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1254 struct pagemapread *pm) 1255 { 1256 pm->buffer[pm->pos++] = *pme; 1257 if (pm->pos >= pm->len) 1258 return PM_END_OF_BUFFER; 1259 return 0; 1260 } 1261 1262 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1263 __always_unused int depth, struct mm_walk *walk) 1264 { 1265 struct pagemapread *pm = walk->private; 1266 unsigned long addr = start; 1267 int err = 0; 1268 1269 while (addr < end) { 1270 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1271 pagemap_entry_t pme = make_pme(0, 0); 1272 /* End of address space hole, which we mark as non-present. */ 1273 unsigned long hole_end; 1274 1275 if (vma) 1276 hole_end = min(end, vma->vm_start); 1277 else 1278 hole_end = end; 1279 1280 for (; addr < hole_end; addr += PAGE_SIZE) { 1281 err = add_to_pagemap(addr, &pme, pm); 1282 if (err) 1283 goto out; 1284 } 1285 1286 if (!vma) 1287 break; 1288 1289 /* Addresses in the VMA. */ 1290 if (vma->vm_flags & VM_SOFTDIRTY) 1291 pme = make_pme(0, PM_SOFT_DIRTY); 1292 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1293 err = add_to_pagemap(addr, &pme, pm); 1294 if (err) 1295 goto out; 1296 } 1297 } 1298 out: 1299 return err; 1300 } 1301 1302 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1303 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1304 { 1305 u64 frame = 0, flags = 0; 1306 struct page *page = NULL; 1307 1308 if (pte_present(pte)) { 1309 if (pm->show_pfn) 1310 frame = pte_pfn(pte); 1311 flags |= PM_PRESENT; 1312 page = vm_normal_page(vma, addr, pte); 1313 if (pte_soft_dirty(pte)) 1314 flags |= PM_SOFT_DIRTY; 1315 } else if (is_swap_pte(pte)) { 1316 swp_entry_t entry; 1317 if (pte_swp_soft_dirty(pte)) 1318 flags |= PM_SOFT_DIRTY; 1319 entry = pte_to_swp_entry(pte); 1320 if (pm->show_pfn) 1321 frame = swp_type(entry) | 1322 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1323 flags |= PM_SWAP; 1324 if (is_migration_entry(entry)) 1325 page = migration_entry_to_page(entry); 1326 1327 if (is_device_private_entry(entry)) 1328 page = device_private_entry_to_page(entry); 1329 } 1330 1331 if (page && !PageAnon(page)) 1332 flags |= PM_FILE; 1333 if (page && page_mapcount(page) == 1) 1334 flags |= PM_MMAP_EXCLUSIVE; 1335 if (vma->vm_flags & VM_SOFTDIRTY) 1336 flags |= PM_SOFT_DIRTY; 1337 1338 return make_pme(frame, flags); 1339 } 1340 1341 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1342 struct mm_walk *walk) 1343 { 1344 struct vm_area_struct *vma = walk->vma; 1345 struct pagemapread *pm = walk->private; 1346 spinlock_t *ptl; 1347 pte_t *pte, *orig_pte; 1348 int err = 0; 1349 1350 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1351 ptl = pmd_trans_huge_lock(pmdp, vma); 1352 if (ptl) { 1353 u64 flags = 0, frame = 0; 1354 pmd_t pmd = *pmdp; 1355 struct page *page = NULL; 1356 1357 if (vma->vm_flags & VM_SOFTDIRTY) 1358 flags |= PM_SOFT_DIRTY; 1359 1360 if (pmd_present(pmd)) { 1361 page = pmd_page(pmd); 1362 1363 flags |= PM_PRESENT; 1364 if (pmd_soft_dirty(pmd)) 1365 flags |= PM_SOFT_DIRTY; 1366 if (pm->show_pfn) 1367 frame = pmd_pfn(pmd) + 1368 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1369 } 1370 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1371 else if (is_swap_pmd(pmd)) { 1372 swp_entry_t entry = pmd_to_swp_entry(pmd); 1373 unsigned long offset; 1374 1375 if (pm->show_pfn) { 1376 offset = swp_offset(entry) + 1377 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1378 frame = swp_type(entry) | 1379 (offset << MAX_SWAPFILES_SHIFT); 1380 } 1381 flags |= PM_SWAP; 1382 if (pmd_swp_soft_dirty(pmd)) 1383 flags |= PM_SOFT_DIRTY; 1384 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1385 page = migration_entry_to_page(entry); 1386 } 1387 #endif 1388 1389 if (page && page_mapcount(page) == 1) 1390 flags |= PM_MMAP_EXCLUSIVE; 1391 1392 for (; addr != end; addr += PAGE_SIZE) { 1393 pagemap_entry_t pme = make_pme(frame, flags); 1394 1395 err = add_to_pagemap(addr, &pme, pm); 1396 if (err) 1397 break; 1398 if (pm->show_pfn) { 1399 if (flags & PM_PRESENT) 1400 frame++; 1401 else if (flags & PM_SWAP) 1402 frame += (1 << MAX_SWAPFILES_SHIFT); 1403 } 1404 } 1405 spin_unlock(ptl); 1406 return err; 1407 } 1408 1409 if (pmd_trans_unstable(pmdp)) 1410 return 0; 1411 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1412 1413 /* 1414 * We can assume that @vma always points to a valid one and @end never 1415 * goes beyond vma->vm_end. 1416 */ 1417 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1418 for (; addr < end; pte++, addr += PAGE_SIZE) { 1419 pagemap_entry_t pme; 1420 1421 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1422 err = add_to_pagemap(addr, &pme, pm); 1423 if (err) 1424 break; 1425 } 1426 pte_unmap_unlock(orig_pte, ptl); 1427 1428 cond_resched(); 1429 1430 return err; 1431 } 1432 1433 #ifdef CONFIG_HUGETLB_PAGE 1434 /* This function walks within one hugetlb entry in the single call */ 1435 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1436 unsigned long addr, unsigned long end, 1437 struct mm_walk *walk) 1438 { 1439 struct pagemapread *pm = walk->private; 1440 struct vm_area_struct *vma = walk->vma; 1441 u64 flags = 0, frame = 0; 1442 int err = 0; 1443 pte_t pte; 1444 1445 if (vma->vm_flags & VM_SOFTDIRTY) 1446 flags |= PM_SOFT_DIRTY; 1447 1448 pte = huge_ptep_get(ptep); 1449 if (pte_present(pte)) { 1450 struct page *page = pte_page(pte); 1451 1452 if (!PageAnon(page)) 1453 flags |= PM_FILE; 1454 1455 if (page_mapcount(page) == 1) 1456 flags |= PM_MMAP_EXCLUSIVE; 1457 1458 flags |= PM_PRESENT; 1459 if (pm->show_pfn) 1460 frame = pte_pfn(pte) + 1461 ((addr & ~hmask) >> PAGE_SHIFT); 1462 } 1463 1464 for (; addr != end; addr += PAGE_SIZE) { 1465 pagemap_entry_t pme = make_pme(frame, flags); 1466 1467 err = add_to_pagemap(addr, &pme, pm); 1468 if (err) 1469 return err; 1470 if (pm->show_pfn && (flags & PM_PRESENT)) 1471 frame++; 1472 } 1473 1474 cond_resched(); 1475 1476 return err; 1477 } 1478 #else 1479 #define pagemap_hugetlb_range NULL 1480 #endif /* HUGETLB_PAGE */ 1481 1482 static const struct mm_walk_ops pagemap_ops = { 1483 .pmd_entry = pagemap_pmd_range, 1484 .pte_hole = pagemap_pte_hole, 1485 .hugetlb_entry = pagemap_hugetlb_range, 1486 }; 1487 1488 /* 1489 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1490 * 1491 * For each page in the address space, this file contains one 64-bit entry 1492 * consisting of the following: 1493 * 1494 * Bits 0-54 page frame number (PFN) if present 1495 * Bits 0-4 swap type if swapped 1496 * Bits 5-54 swap offset if swapped 1497 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1498 * Bit 56 page exclusively mapped 1499 * Bits 57-60 zero 1500 * Bit 61 page is file-page or shared-anon 1501 * Bit 62 page swapped 1502 * Bit 63 page present 1503 * 1504 * If the page is not present but in swap, then the PFN contains an 1505 * encoding of the swap file number and the page's offset into the 1506 * swap. Unmapped pages return a null PFN. This allows determining 1507 * precisely which pages are mapped (or in swap) and comparing mapped 1508 * pages between processes. 1509 * 1510 * Efficient users of this interface will use /proc/pid/maps to 1511 * determine which areas of memory are actually mapped and llseek to 1512 * skip over unmapped regions. 1513 */ 1514 static ssize_t pagemap_read(struct file *file, char __user *buf, 1515 size_t count, loff_t *ppos) 1516 { 1517 struct mm_struct *mm = file->private_data; 1518 struct pagemapread pm; 1519 unsigned long src; 1520 unsigned long svpfn; 1521 unsigned long start_vaddr; 1522 unsigned long end_vaddr; 1523 int ret = 0, copied = 0; 1524 1525 if (!mm || !mmget_not_zero(mm)) 1526 goto out; 1527 1528 ret = -EINVAL; 1529 /* file position must be aligned */ 1530 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1531 goto out_mm; 1532 1533 ret = 0; 1534 if (!count) 1535 goto out_mm; 1536 1537 /* do not disclose physical addresses: attack vector */ 1538 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1539 1540 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1541 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1542 ret = -ENOMEM; 1543 if (!pm.buffer) 1544 goto out_mm; 1545 1546 src = *ppos; 1547 svpfn = src / PM_ENTRY_BYTES; 1548 start_vaddr = svpfn << PAGE_SHIFT; 1549 end_vaddr = mm->task_size; 1550 1551 /* watch out for wraparound */ 1552 if (svpfn > mm->task_size >> PAGE_SHIFT) 1553 start_vaddr = end_vaddr; 1554 1555 /* 1556 * The odds are that this will stop walking way 1557 * before end_vaddr, because the length of the 1558 * user buffer is tracked in "pm", and the walk 1559 * will stop when we hit the end of the buffer. 1560 */ 1561 ret = 0; 1562 while (count && (start_vaddr < end_vaddr)) { 1563 int len; 1564 unsigned long end; 1565 1566 pm.pos = 0; 1567 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1568 /* overflow ? */ 1569 if (end < start_vaddr || end > end_vaddr) 1570 end = end_vaddr; 1571 ret = mmap_read_lock_killable(mm); 1572 if (ret) 1573 goto out_free; 1574 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1575 mmap_read_unlock(mm); 1576 start_vaddr = end; 1577 1578 len = min(count, PM_ENTRY_BYTES * pm.pos); 1579 if (copy_to_user(buf, pm.buffer, len)) { 1580 ret = -EFAULT; 1581 goto out_free; 1582 } 1583 copied += len; 1584 buf += len; 1585 count -= len; 1586 } 1587 *ppos += copied; 1588 if (!ret || ret == PM_END_OF_BUFFER) 1589 ret = copied; 1590 1591 out_free: 1592 kfree(pm.buffer); 1593 out_mm: 1594 mmput(mm); 1595 out: 1596 return ret; 1597 } 1598 1599 static int pagemap_open(struct inode *inode, struct file *file) 1600 { 1601 struct mm_struct *mm; 1602 1603 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1604 if (IS_ERR(mm)) 1605 return PTR_ERR(mm); 1606 file->private_data = mm; 1607 return 0; 1608 } 1609 1610 static int pagemap_release(struct inode *inode, struct file *file) 1611 { 1612 struct mm_struct *mm = file->private_data; 1613 1614 if (mm) 1615 mmdrop(mm); 1616 return 0; 1617 } 1618 1619 const struct file_operations proc_pagemap_operations = { 1620 .llseek = mem_lseek, /* borrow this */ 1621 .read = pagemap_read, 1622 .open = pagemap_open, 1623 .release = pagemap_release, 1624 }; 1625 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1626 1627 #ifdef CONFIG_NUMA 1628 1629 struct numa_maps { 1630 unsigned long pages; 1631 unsigned long anon; 1632 unsigned long active; 1633 unsigned long writeback; 1634 unsigned long mapcount_max; 1635 unsigned long dirty; 1636 unsigned long swapcache; 1637 unsigned long node[MAX_NUMNODES]; 1638 }; 1639 1640 struct numa_maps_private { 1641 struct proc_maps_private proc_maps; 1642 struct numa_maps md; 1643 }; 1644 1645 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1646 unsigned long nr_pages) 1647 { 1648 int count = page_mapcount(page); 1649 1650 md->pages += nr_pages; 1651 if (pte_dirty || PageDirty(page)) 1652 md->dirty += nr_pages; 1653 1654 if (PageSwapCache(page)) 1655 md->swapcache += nr_pages; 1656 1657 if (PageActive(page) || PageUnevictable(page)) 1658 md->active += nr_pages; 1659 1660 if (PageWriteback(page)) 1661 md->writeback += nr_pages; 1662 1663 if (PageAnon(page)) 1664 md->anon += nr_pages; 1665 1666 if (count > md->mapcount_max) 1667 md->mapcount_max = count; 1668 1669 md->node[page_to_nid(page)] += nr_pages; 1670 } 1671 1672 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1673 unsigned long addr) 1674 { 1675 struct page *page; 1676 int nid; 1677 1678 if (!pte_present(pte)) 1679 return NULL; 1680 1681 page = vm_normal_page(vma, addr, pte); 1682 if (!page) 1683 return NULL; 1684 1685 if (PageReserved(page)) 1686 return NULL; 1687 1688 nid = page_to_nid(page); 1689 if (!node_isset(nid, node_states[N_MEMORY])) 1690 return NULL; 1691 1692 return page; 1693 } 1694 1695 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1696 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1697 struct vm_area_struct *vma, 1698 unsigned long addr) 1699 { 1700 struct page *page; 1701 int nid; 1702 1703 if (!pmd_present(pmd)) 1704 return NULL; 1705 1706 page = vm_normal_page_pmd(vma, addr, pmd); 1707 if (!page) 1708 return NULL; 1709 1710 if (PageReserved(page)) 1711 return NULL; 1712 1713 nid = page_to_nid(page); 1714 if (!node_isset(nid, node_states[N_MEMORY])) 1715 return NULL; 1716 1717 return page; 1718 } 1719 #endif 1720 1721 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1722 unsigned long end, struct mm_walk *walk) 1723 { 1724 struct numa_maps *md = walk->private; 1725 struct vm_area_struct *vma = walk->vma; 1726 spinlock_t *ptl; 1727 pte_t *orig_pte; 1728 pte_t *pte; 1729 1730 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1731 ptl = pmd_trans_huge_lock(pmd, vma); 1732 if (ptl) { 1733 struct page *page; 1734 1735 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1736 if (page) 1737 gather_stats(page, md, pmd_dirty(*pmd), 1738 HPAGE_PMD_SIZE/PAGE_SIZE); 1739 spin_unlock(ptl); 1740 return 0; 1741 } 1742 1743 if (pmd_trans_unstable(pmd)) 1744 return 0; 1745 #endif 1746 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1747 do { 1748 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1749 if (!page) 1750 continue; 1751 gather_stats(page, md, pte_dirty(*pte), 1); 1752 1753 } while (pte++, addr += PAGE_SIZE, addr != end); 1754 pte_unmap_unlock(orig_pte, ptl); 1755 cond_resched(); 1756 return 0; 1757 } 1758 #ifdef CONFIG_HUGETLB_PAGE 1759 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1760 unsigned long addr, unsigned long end, struct mm_walk *walk) 1761 { 1762 pte_t huge_pte = huge_ptep_get(pte); 1763 struct numa_maps *md; 1764 struct page *page; 1765 1766 if (!pte_present(huge_pte)) 1767 return 0; 1768 1769 page = pte_page(huge_pte); 1770 if (!page) 1771 return 0; 1772 1773 md = walk->private; 1774 gather_stats(page, md, pte_dirty(huge_pte), 1); 1775 return 0; 1776 } 1777 1778 #else 1779 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1780 unsigned long addr, unsigned long end, struct mm_walk *walk) 1781 { 1782 return 0; 1783 } 1784 #endif 1785 1786 static const struct mm_walk_ops show_numa_ops = { 1787 .hugetlb_entry = gather_hugetlb_stats, 1788 .pmd_entry = gather_pte_stats, 1789 }; 1790 1791 /* 1792 * Display pages allocated per node and memory policy via /proc. 1793 */ 1794 static int show_numa_map(struct seq_file *m, void *v) 1795 { 1796 struct numa_maps_private *numa_priv = m->private; 1797 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1798 struct vm_area_struct *vma = v; 1799 struct numa_maps *md = &numa_priv->md; 1800 struct file *file = vma->vm_file; 1801 struct mm_struct *mm = vma->vm_mm; 1802 struct mempolicy *pol; 1803 char buffer[64]; 1804 int nid; 1805 1806 if (!mm) 1807 return 0; 1808 1809 /* Ensure we start with an empty set of numa_maps statistics. */ 1810 memset(md, 0, sizeof(*md)); 1811 1812 pol = __get_vma_policy(vma, vma->vm_start); 1813 if (pol) { 1814 mpol_to_str(buffer, sizeof(buffer), pol); 1815 mpol_cond_put(pol); 1816 } else { 1817 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1818 } 1819 1820 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1821 1822 if (file) { 1823 seq_puts(m, " file="); 1824 seq_file_path(m, file, "\n\t= "); 1825 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1826 seq_puts(m, " heap"); 1827 } else if (is_stack(vma)) { 1828 seq_puts(m, " stack"); 1829 } 1830 1831 if (is_vm_hugetlb_page(vma)) 1832 seq_puts(m, " huge"); 1833 1834 /* mmap_lock is held by m_start */ 1835 walk_page_vma(vma, &show_numa_ops, md); 1836 1837 if (!md->pages) 1838 goto out; 1839 1840 if (md->anon) 1841 seq_printf(m, " anon=%lu", md->anon); 1842 1843 if (md->dirty) 1844 seq_printf(m, " dirty=%lu", md->dirty); 1845 1846 if (md->pages != md->anon && md->pages != md->dirty) 1847 seq_printf(m, " mapped=%lu", md->pages); 1848 1849 if (md->mapcount_max > 1) 1850 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1851 1852 if (md->swapcache) 1853 seq_printf(m, " swapcache=%lu", md->swapcache); 1854 1855 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1856 seq_printf(m, " active=%lu", md->active); 1857 1858 if (md->writeback) 1859 seq_printf(m, " writeback=%lu", md->writeback); 1860 1861 for_each_node_state(nid, N_MEMORY) 1862 if (md->node[nid]) 1863 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1864 1865 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1866 out: 1867 seq_putc(m, '\n'); 1868 return 0; 1869 } 1870 1871 static const struct seq_operations proc_pid_numa_maps_op = { 1872 .start = m_start, 1873 .next = m_next, 1874 .stop = m_stop, 1875 .show = show_numa_map, 1876 }; 1877 1878 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1879 { 1880 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1881 sizeof(struct numa_maps_private)); 1882 } 1883 1884 const struct file_operations proc_pid_numa_maps_operations = { 1885 .open = pid_numa_maps_open, 1886 .read = seq_read, 1887 .llseek = seq_lseek, 1888 .release = proc_map_release, 1889 }; 1890 1891 #endif /* CONFIG_NUMA */ 1892