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 (down_read_killable(&mm->mmap_sem)) { 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 up_read(&mm->mmap_sem); 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; 550 551 /* FOLL_DUMP will return -EFAULT on huge zero page */ 552 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 553 if (IS_ERR_OR_NULL(page)) 554 return; 555 if (PageAnon(page)) 556 mss->anonymous_thp += HPAGE_PMD_SIZE; 557 else if (PageSwapBacked(page)) 558 mss->shmem_thp += HPAGE_PMD_SIZE; 559 else if (is_zone_device_page(page)) 560 /* pass */; 561 else 562 mss->file_thp += HPAGE_PMD_SIZE; 563 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked); 564 } 565 #else 566 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 567 struct mm_walk *walk) 568 { 569 } 570 #endif 571 572 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 573 struct mm_walk *walk) 574 { 575 struct vm_area_struct *vma = walk->vma; 576 pte_t *pte; 577 spinlock_t *ptl; 578 579 ptl = pmd_trans_huge_lock(pmd, vma); 580 if (ptl) { 581 if (pmd_present(*pmd)) 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_sem 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 #ifdef CONFIG_X86_INTEL_MPX 626 [ilog2(VM_MPX)] = "mp", 627 #endif 628 [ilog2(VM_LOCKED)] = "lo", 629 [ilog2(VM_IO)] = "io", 630 [ilog2(VM_SEQ_READ)] = "sr", 631 [ilog2(VM_RAND_READ)] = "rr", 632 [ilog2(VM_DONTCOPY)] = "dc", 633 [ilog2(VM_DONTEXPAND)] = "de", 634 [ilog2(VM_ACCOUNT)] = "ac", 635 [ilog2(VM_NORESERVE)] = "nr", 636 [ilog2(VM_HUGETLB)] = "ht", 637 [ilog2(VM_SYNC)] = "sf", 638 [ilog2(VM_ARCH_1)] = "ar", 639 [ilog2(VM_WIPEONFORK)] = "wf", 640 [ilog2(VM_DONTDUMP)] = "dd", 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_ARCH_HAS_PKEYS 651 /* These come out via ProtectionKey: */ 652 [ilog2(VM_PKEY_BIT0)] = "", 653 [ilog2(VM_PKEY_BIT1)] = "", 654 [ilog2(VM_PKEY_BIT2)] = "", 655 [ilog2(VM_PKEY_BIT3)] = "", 656 #if VM_PKEY_BIT4 657 [ilog2(VM_PKEY_BIT4)] = "", 658 #endif 659 #endif /* CONFIG_ARCH_HAS_PKEYS */ 660 }; 661 size_t i; 662 663 seq_puts(m, "VmFlags: "); 664 for (i = 0; i < BITS_PER_LONG; i++) { 665 if (!mnemonics[i][0]) 666 continue; 667 if (vma->vm_flags & (1UL << i)) { 668 seq_putc(m, mnemonics[i][0]); 669 seq_putc(m, mnemonics[i][1]); 670 seq_putc(m, ' '); 671 } 672 } 673 seq_putc(m, '\n'); 674 } 675 676 #ifdef CONFIG_HUGETLB_PAGE 677 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 678 unsigned long addr, unsigned long end, 679 struct mm_walk *walk) 680 { 681 struct mem_size_stats *mss = walk->private; 682 struct vm_area_struct *vma = walk->vma; 683 struct page *page = NULL; 684 685 if (pte_present(*pte)) { 686 page = vm_normal_page(vma, addr, *pte); 687 } else if (is_swap_pte(*pte)) { 688 swp_entry_t swpent = pte_to_swp_entry(*pte); 689 690 if (is_migration_entry(swpent)) 691 page = migration_entry_to_page(swpent); 692 else if (is_device_private_entry(swpent)) 693 page = device_private_entry_to_page(swpent); 694 } 695 if (page) { 696 int mapcount = page_mapcount(page); 697 698 if (mapcount >= 2) 699 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 700 else 701 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 702 } 703 return 0; 704 } 705 #else 706 #define smaps_hugetlb_range NULL 707 #endif /* HUGETLB_PAGE */ 708 709 static const struct mm_walk_ops smaps_walk_ops = { 710 .pmd_entry = smaps_pte_range, 711 .hugetlb_entry = smaps_hugetlb_range, 712 }; 713 714 static const struct mm_walk_ops smaps_shmem_walk_ops = { 715 .pmd_entry = smaps_pte_range, 716 .hugetlb_entry = smaps_hugetlb_range, 717 .pte_hole = smaps_pte_hole, 718 }; 719 720 static void smap_gather_stats(struct vm_area_struct *vma, 721 struct mem_size_stats *mss) 722 { 723 #ifdef CONFIG_SHMEM 724 /* In case of smaps_rollup, reset the value from previous vma */ 725 mss->check_shmem_swap = false; 726 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 727 /* 728 * For shared or readonly shmem mappings we know that all 729 * swapped out pages belong to the shmem object, and we can 730 * obtain the swap value much more efficiently. For private 731 * writable mappings, we might have COW pages that are 732 * not affected by the parent swapped out pages of the shmem 733 * object, so we have to distinguish them during the page walk. 734 * Unless we know that the shmem object (or the part mapped by 735 * our VMA) has no swapped out pages at all. 736 */ 737 unsigned long shmem_swapped = shmem_swap_usage(vma); 738 739 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 740 !(vma->vm_flags & VM_WRITE)) { 741 mss->swap += shmem_swapped; 742 } else { 743 mss->check_shmem_swap = true; 744 walk_page_vma(vma, &smaps_shmem_walk_ops, mss); 745 return; 746 } 747 } 748 #endif 749 /* mmap_sem is held in m_start */ 750 walk_page_vma(vma, &smaps_walk_ops, mss); 751 } 752 753 #define SEQ_PUT_DEC(str, val) \ 754 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 755 756 /* Show the contents common for smaps and smaps_rollup */ 757 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 758 bool rollup_mode) 759 { 760 SEQ_PUT_DEC("Rss: ", mss->resident); 761 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 762 if (rollup_mode) { 763 /* 764 * These are meaningful only for smaps_rollup, otherwise two of 765 * them are zero, and the other one is the same as Pss. 766 */ 767 SEQ_PUT_DEC(" kB\nPss_Anon: ", 768 mss->pss_anon >> PSS_SHIFT); 769 SEQ_PUT_DEC(" kB\nPss_File: ", 770 mss->pss_file >> PSS_SHIFT); 771 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 772 mss->pss_shmem >> PSS_SHIFT); 773 } 774 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 775 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 776 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 777 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 778 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 779 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 780 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 781 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 782 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 783 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 784 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 785 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 786 mss->private_hugetlb >> 10, 7); 787 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 788 SEQ_PUT_DEC(" kB\nSwapPss: ", 789 mss->swap_pss >> PSS_SHIFT); 790 SEQ_PUT_DEC(" kB\nLocked: ", 791 mss->pss_locked >> PSS_SHIFT); 792 seq_puts(m, " kB\n"); 793 } 794 795 static int show_smap(struct seq_file *m, void *v) 796 { 797 struct vm_area_struct *vma = v; 798 struct mem_size_stats mss; 799 800 memset(&mss, 0, sizeof(mss)); 801 802 smap_gather_stats(vma, &mss); 803 804 show_map_vma(m, vma); 805 806 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 807 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 808 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 809 seq_puts(m, " kB\n"); 810 811 __show_smap(m, &mss, false); 812 813 seq_printf(m, "THPeligible: %d\n", 814 transparent_hugepage_enabled(vma)); 815 816 if (arch_pkeys_enabled()) 817 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 818 show_smap_vma_flags(m, vma); 819 820 return 0; 821 } 822 823 static int show_smaps_rollup(struct seq_file *m, void *v) 824 { 825 struct proc_maps_private *priv = m->private; 826 struct mem_size_stats mss; 827 struct mm_struct *mm; 828 struct vm_area_struct *vma; 829 unsigned long last_vma_end = 0; 830 int ret = 0; 831 832 priv->task = get_proc_task(priv->inode); 833 if (!priv->task) 834 return -ESRCH; 835 836 mm = priv->mm; 837 if (!mm || !mmget_not_zero(mm)) { 838 ret = -ESRCH; 839 goto out_put_task; 840 } 841 842 memset(&mss, 0, sizeof(mss)); 843 844 ret = down_read_killable(&mm->mmap_sem); 845 if (ret) 846 goto out_put_mm; 847 848 hold_task_mempolicy(priv); 849 850 for (vma = priv->mm->mmap; vma; vma = vma->vm_next) { 851 smap_gather_stats(vma, &mss); 852 last_vma_end = vma->vm_end; 853 } 854 855 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 856 last_vma_end, 0, 0, 0, 0); 857 seq_pad(m, ' '); 858 seq_puts(m, "[rollup]\n"); 859 860 __show_smap(m, &mss, true); 861 862 release_task_mempolicy(priv); 863 up_read(&mm->mmap_sem); 864 865 out_put_mm: 866 mmput(mm); 867 out_put_task: 868 put_task_struct(priv->task); 869 priv->task = NULL; 870 871 return ret; 872 } 873 #undef SEQ_PUT_DEC 874 875 static const struct seq_operations proc_pid_smaps_op = { 876 .start = m_start, 877 .next = m_next, 878 .stop = m_stop, 879 .show = show_smap 880 }; 881 882 static int pid_smaps_open(struct inode *inode, struct file *file) 883 { 884 return do_maps_open(inode, file, &proc_pid_smaps_op); 885 } 886 887 static int smaps_rollup_open(struct inode *inode, struct file *file) 888 { 889 int ret; 890 struct proc_maps_private *priv; 891 892 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 893 if (!priv) 894 return -ENOMEM; 895 896 ret = single_open(file, show_smaps_rollup, priv); 897 if (ret) 898 goto out_free; 899 900 priv->inode = inode; 901 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 902 if (IS_ERR(priv->mm)) { 903 ret = PTR_ERR(priv->mm); 904 905 single_release(inode, file); 906 goto out_free; 907 } 908 909 return 0; 910 911 out_free: 912 kfree(priv); 913 return ret; 914 } 915 916 static int smaps_rollup_release(struct inode *inode, struct file *file) 917 { 918 struct seq_file *seq = file->private_data; 919 struct proc_maps_private *priv = seq->private; 920 921 if (priv->mm) 922 mmdrop(priv->mm); 923 924 kfree(priv); 925 return single_release(inode, file); 926 } 927 928 const struct file_operations proc_pid_smaps_operations = { 929 .open = pid_smaps_open, 930 .read = seq_read, 931 .llseek = seq_lseek, 932 .release = proc_map_release, 933 }; 934 935 const struct file_operations proc_pid_smaps_rollup_operations = { 936 .open = smaps_rollup_open, 937 .read = seq_read, 938 .llseek = seq_lseek, 939 .release = smaps_rollup_release, 940 }; 941 942 enum clear_refs_types { 943 CLEAR_REFS_ALL = 1, 944 CLEAR_REFS_ANON, 945 CLEAR_REFS_MAPPED, 946 CLEAR_REFS_SOFT_DIRTY, 947 CLEAR_REFS_MM_HIWATER_RSS, 948 CLEAR_REFS_LAST, 949 }; 950 951 struct clear_refs_private { 952 enum clear_refs_types type; 953 }; 954 955 #ifdef CONFIG_MEM_SOFT_DIRTY 956 static inline void clear_soft_dirty(struct vm_area_struct *vma, 957 unsigned long addr, pte_t *pte) 958 { 959 /* 960 * The soft-dirty tracker uses #PF-s to catch writes 961 * to pages, so write-protect the pte as well. See the 962 * Documentation/admin-guide/mm/soft-dirty.rst for full description 963 * of how soft-dirty works. 964 */ 965 pte_t ptent = *pte; 966 967 if (pte_present(ptent)) { 968 pte_t old_pte; 969 970 old_pte = ptep_modify_prot_start(vma, addr, pte); 971 ptent = pte_wrprotect(old_pte); 972 ptent = pte_clear_soft_dirty(ptent); 973 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 974 } else if (is_swap_pte(ptent)) { 975 ptent = pte_swp_clear_soft_dirty(ptent); 976 set_pte_at(vma->vm_mm, addr, pte, ptent); 977 } 978 } 979 #else 980 static inline void clear_soft_dirty(struct vm_area_struct *vma, 981 unsigned long addr, pte_t *pte) 982 { 983 } 984 #endif 985 986 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 987 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 988 unsigned long addr, pmd_t *pmdp) 989 { 990 pmd_t old, pmd = *pmdp; 991 992 if (pmd_present(pmd)) { 993 /* See comment in change_huge_pmd() */ 994 old = pmdp_invalidate(vma, addr, pmdp); 995 if (pmd_dirty(old)) 996 pmd = pmd_mkdirty(pmd); 997 if (pmd_young(old)) 998 pmd = pmd_mkyoung(pmd); 999 1000 pmd = pmd_wrprotect(pmd); 1001 pmd = pmd_clear_soft_dirty(pmd); 1002 1003 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1004 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1005 pmd = pmd_swp_clear_soft_dirty(pmd); 1006 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1007 } 1008 } 1009 #else 1010 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1011 unsigned long addr, pmd_t *pmdp) 1012 { 1013 } 1014 #endif 1015 1016 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1017 unsigned long end, struct mm_walk *walk) 1018 { 1019 struct clear_refs_private *cp = walk->private; 1020 struct vm_area_struct *vma = walk->vma; 1021 pte_t *pte, ptent; 1022 spinlock_t *ptl; 1023 struct page *page; 1024 1025 ptl = pmd_trans_huge_lock(pmd, vma); 1026 if (ptl) { 1027 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1028 clear_soft_dirty_pmd(vma, addr, pmd); 1029 goto out; 1030 } 1031 1032 if (!pmd_present(*pmd)) 1033 goto out; 1034 1035 page = pmd_page(*pmd); 1036 1037 /* Clear accessed and referenced bits. */ 1038 pmdp_test_and_clear_young(vma, addr, pmd); 1039 test_and_clear_page_young(page); 1040 ClearPageReferenced(page); 1041 out: 1042 spin_unlock(ptl); 1043 return 0; 1044 } 1045 1046 if (pmd_trans_unstable(pmd)) 1047 return 0; 1048 1049 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1050 for (; addr != end; pte++, addr += PAGE_SIZE) { 1051 ptent = *pte; 1052 1053 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1054 clear_soft_dirty(vma, addr, pte); 1055 continue; 1056 } 1057 1058 if (!pte_present(ptent)) 1059 continue; 1060 1061 page = vm_normal_page(vma, addr, ptent); 1062 if (!page) 1063 continue; 1064 1065 /* Clear accessed and referenced bits. */ 1066 ptep_test_and_clear_young(vma, addr, pte); 1067 test_and_clear_page_young(page); 1068 ClearPageReferenced(page); 1069 } 1070 pte_unmap_unlock(pte - 1, ptl); 1071 cond_resched(); 1072 return 0; 1073 } 1074 1075 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1076 struct mm_walk *walk) 1077 { 1078 struct clear_refs_private *cp = walk->private; 1079 struct vm_area_struct *vma = walk->vma; 1080 1081 if (vma->vm_flags & VM_PFNMAP) 1082 return 1; 1083 1084 /* 1085 * Writing 1 to /proc/pid/clear_refs affects all pages. 1086 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1087 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1088 * Writing 4 to /proc/pid/clear_refs affects all pages. 1089 */ 1090 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1091 return 1; 1092 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1093 return 1; 1094 return 0; 1095 } 1096 1097 static const struct mm_walk_ops clear_refs_walk_ops = { 1098 .pmd_entry = clear_refs_pte_range, 1099 .test_walk = clear_refs_test_walk, 1100 }; 1101 1102 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1103 size_t count, loff_t *ppos) 1104 { 1105 struct task_struct *task; 1106 char buffer[PROC_NUMBUF]; 1107 struct mm_struct *mm; 1108 struct vm_area_struct *vma; 1109 enum clear_refs_types type; 1110 struct mmu_gather tlb; 1111 int itype; 1112 int rv; 1113 1114 memset(buffer, 0, sizeof(buffer)); 1115 if (count > sizeof(buffer) - 1) 1116 count = sizeof(buffer) - 1; 1117 if (copy_from_user(buffer, buf, count)) 1118 return -EFAULT; 1119 rv = kstrtoint(strstrip(buffer), 10, &itype); 1120 if (rv < 0) 1121 return rv; 1122 type = (enum clear_refs_types)itype; 1123 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1124 return -EINVAL; 1125 1126 task = get_proc_task(file_inode(file)); 1127 if (!task) 1128 return -ESRCH; 1129 mm = get_task_mm(task); 1130 if (mm) { 1131 struct mmu_notifier_range range; 1132 struct clear_refs_private cp = { 1133 .type = type, 1134 }; 1135 1136 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1137 if (down_write_killable(&mm->mmap_sem)) { 1138 count = -EINTR; 1139 goto out_mm; 1140 } 1141 1142 /* 1143 * Writing 5 to /proc/pid/clear_refs resets the peak 1144 * resident set size to this mm's current rss value. 1145 */ 1146 reset_mm_hiwater_rss(mm); 1147 up_write(&mm->mmap_sem); 1148 goto out_mm; 1149 } 1150 1151 if (down_read_killable(&mm->mmap_sem)) { 1152 count = -EINTR; 1153 goto out_mm; 1154 } 1155 tlb_gather_mmu(&tlb, mm, 0, -1); 1156 if (type == CLEAR_REFS_SOFT_DIRTY) { 1157 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1158 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1159 continue; 1160 up_read(&mm->mmap_sem); 1161 if (down_write_killable(&mm->mmap_sem)) { 1162 count = -EINTR; 1163 goto out_mm; 1164 } 1165 /* 1166 * Avoid to modify vma->vm_flags 1167 * without locked ops while the 1168 * coredump reads the vm_flags. 1169 */ 1170 if (!mmget_still_valid(mm)) { 1171 /* 1172 * Silently return "count" 1173 * like if get_task_mm() 1174 * failed. FIXME: should this 1175 * function have returned 1176 * -ESRCH if get_task_mm() 1177 * failed like if 1178 * get_proc_task() fails? 1179 */ 1180 up_write(&mm->mmap_sem); 1181 goto out_mm; 1182 } 1183 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1184 vma->vm_flags &= ~VM_SOFTDIRTY; 1185 vma_set_page_prot(vma); 1186 } 1187 downgrade_write(&mm->mmap_sem); 1188 break; 1189 } 1190 1191 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1192 0, NULL, mm, 0, -1UL); 1193 mmu_notifier_invalidate_range_start(&range); 1194 } 1195 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1196 &cp); 1197 if (type == CLEAR_REFS_SOFT_DIRTY) 1198 mmu_notifier_invalidate_range_end(&range); 1199 tlb_finish_mmu(&tlb, 0, -1); 1200 up_read(&mm->mmap_sem); 1201 out_mm: 1202 mmput(mm); 1203 } 1204 put_task_struct(task); 1205 1206 return count; 1207 } 1208 1209 const struct file_operations proc_clear_refs_operations = { 1210 .write = clear_refs_write, 1211 .llseek = noop_llseek, 1212 }; 1213 1214 typedef struct { 1215 u64 pme; 1216 } pagemap_entry_t; 1217 1218 struct pagemapread { 1219 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1220 pagemap_entry_t *buffer; 1221 bool show_pfn; 1222 }; 1223 1224 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1225 #define PAGEMAP_WALK_MASK (PMD_MASK) 1226 1227 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1228 #define PM_PFRAME_BITS 55 1229 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1230 #define PM_SOFT_DIRTY BIT_ULL(55) 1231 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1232 #define PM_FILE BIT_ULL(61) 1233 #define PM_SWAP BIT_ULL(62) 1234 #define PM_PRESENT BIT_ULL(63) 1235 1236 #define PM_END_OF_BUFFER 1 1237 1238 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1239 { 1240 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1241 } 1242 1243 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1244 struct pagemapread *pm) 1245 { 1246 pm->buffer[pm->pos++] = *pme; 1247 if (pm->pos >= pm->len) 1248 return PM_END_OF_BUFFER; 1249 return 0; 1250 } 1251 1252 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1253 __always_unused int depth, struct mm_walk *walk) 1254 { 1255 struct pagemapread *pm = walk->private; 1256 unsigned long addr = start; 1257 int err = 0; 1258 1259 while (addr < end) { 1260 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1261 pagemap_entry_t pme = make_pme(0, 0); 1262 /* End of address space hole, which we mark as non-present. */ 1263 unsigned long hole_end; 1264 1265 if (vma) 1266 hole_end = min(end, vma->vm_start); 1267 else 1268 hole_end = end; 1269 1270 for (; addr < hole_end; addr += PAGE_SIZE) { 1271 err = add_to_pagemap(addr, &pme, pm); 1272 if (err) 1273 goto out; 1274 } 1275 1276 if (!vma) 1277 break; 1278 1279 /* Addresses in the VMA. */ 1280 if (vma->vm_flags & VM_SOFTDIRTY) 1281 pme = make_pme(0, PM_SOFT_DIRTY); 1282 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1283 err = add_to_pagemap(addr, &pme, pm); 1284 if (err) 1285 goto out; 1286 } 1287 } 1288 out: 1289 return err; 1290 } 1291 1292 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1293 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1294 { 1295 u64 frame = 0, flags = 0; 1296 struct page *page = NULL; 1297 1298 if (pte_present(pte)) { 1299 if (pm->show_pfn) 1300 frame = pte_pfn(pte); 1301 flags |= PM_PRESENT; 1302 page = vm_normal_page(vma, addr, pte); 1303 if (pte_soft_dirty(pte)) 1304 flags |= PM_SOFT_DIRTY; 1305 } else if (is_swap_pte(pte)) { 1306 swp_entry_t entry; 1307 if (pte_swp_soft_dirty(pte)) 1308 flags |= PM_SOFT_DIRTY; 1309 entry = pte_to_swp_entry(pte); 1310 if (pm->show_pfn) 1311 frame = swp_type(entry) | 1312 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1313 flags |= PM_SWAP; 1314 if (is_migration_entry(entry)) 1315 page = migration_entry_to_page(entry); 1316 1317 if (is_device_private_entry(entry)) 1318 page = device_private_entry_to_page(entry); 1319 } 1320 1321 if (page && !PageAnon(page)) 1322 flags |= PM_FILE; 1323 if (page && page_mapcount(page) == 1) 1324 flags |= PM_MMAP_EXCLUSIVE; 1325 if (vma->vm_flags & VM_SOFTDIRTY) 1326 flags |= PM_SOFT_DIRTY; 1327 1328 return make_pme(frame, flags); 1329 } 1330 1331 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1332 struct mm_walk *walk) 1333 { 1334 struct vm_area_struct *vma = walk->vma; 1335 struct pagemapread *pm = walk->private; 1336 spinlock_t *ptl; 1337 pte_t *pte, *orig_pte; 1338 int err = 0; 1339 1340 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1341 ptl = pmd_trans_huge_lock(pmdp, vma); 1342 if (ptl) { 1343 u64 flags = 0, frame = 0; 1344 pmd_t pmd = *pmdp; 1345 struct page *page = NULL; 1346 1347 if (vma->vm_flags & VM_SOFTDIRTY) 1348 flags |= PM_SOFT_DIRTY; 1349 1350 if (pmd_present(pmd)) { 1351 page = pmd_page(pmd); 1352 1353 flags |= PM_PRESENT; 1354 if (pmd_soft_dirty(pmd)) 1355 flags |= PM_SOFT_DIRTY; 1356 if (pm->show_pfn) 1357 frame = pmd_pfn(pmd) + 1358 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1359 } 1360 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1361 else if (is_swap_pmd(pmd)) { 1362 swp_entry_t entry = pmd_to_swp_entry(pmd); 1363 unsigned long offset; 1364 1365 if (pm->show_pfn) { 1366 offset = swp_offset(entry) + 1367 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1368 frame = swp_type(entry) | 1369 (offset << MAX_SWAPFILES_SHIFT); 1370 } 1371 flags |= PM_SWAP; 1372 if (pmd_swp_soft_dirty(pmd)) 1373 flags |= PM_SOFT_DIRTY; 1374 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1375 page = migration_entry_to_page(entry); 1376 } 1377 #endif 1378 1379 if (page && page_mapcount(page) == 1) 1380 flags |= PM_MMAP_EXCLUSIVE; 1381 1382 for (; addr != end; addr += PAGE_SIZE) { 1383 pagemap_entry_t pme = make_pme(frame, flags); 1384 1385 err = add_to_pagemap(addr, &pme, pm); 1386 if (err) 1387 break; 1388 if (pm->show_pfn) { 1389 if (flags & PM_PRESENT) 1390 frame++; 1391 else if (flags & PM_SWAP) 1392 frame += (1 << MAX_SWAPFILES_SHIFT); 1393 } 1394 } 1395 spin_unlock(ptl); 1396 return err; 1397 } 1398 1399 if (pmd_trans_unstable(pmdp)) 1400 return 0; 1401 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1402 1403 /* 1404 * We can assume that @vma always points to a valid one and @end never 1405 * goes beyond vma->vm_end. 1406 */ 1407 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1408 for (; addr < end; pte++, addr += PAGE_SIZE) { 1409 pagemap_entry_t pme; 1410 1411 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1412 err = add_to_pagemap(addr, &pme, pm); 1413 if (err) 1414 break; 1415 } 1416 pte_unmap_unlock(orig_pte, ptl); 1417 1418 cond_resched(); 1419 1420 return err; 1421 } 1422 1423 #ifdef CONFIG_HUGETLB_PAGE 1424 /* This function walks within one hugetlb entry in the single call */ 1425 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1426 unsigned long addr, unsigned long end, 1427 struct mm_walk *walk) 1428 { 1429 struct pagemapread *pm = walk->private; 1430 struct vm_area_struct *vma = walk->vma; 1431 u64 flags = 0, frame = 0; 1432 int err = 0; 1433 pte_t pte; 1434 1435 if (vma->vm_flags & VM_SOFTDIRTY) 1436 flags |= PM_SOFT_DIRTY; 1437 1438 pte = huge_ptep_get(ptep); 1439 if (pte_present(pte)) { 1440 struct page *page = pte_page(pte); 1441 1442 if (!PageAnon(page)) 1443 flags |= PM_FILE; 1444 1445 if (page_mapcount(page) == 1) 1446 flags |= PM_MMAP_EXCLUSIVE; 1447 1448 flags |= PM_PRESENT; 1449 if (pm->show_pfn) 1450 frame = pte_pfn(pte) + 1451 ((addr & ~hmask) >> PAGE_SHIFT); 1452 } 1453 1454 for (; addr != end; addr += PAGE_SIZE) { 1455 pagemap_entry_t pme = make_pme(frame, flags); 1456 1457 err = add_to_pagemap(addr, &pme, pm); 1458 if (err) 1459 return err; 1460 if (pm->show_pfn && (flags & PM_PRESENT)) 1461 frame++; 1462 } 1463 1464 cond_resched(); 1465 1466 return err; 1467 } 1468 #else 1469 #define pagemap_hugetlb_range NULL 1470 #endif /* HUGETLB_PAGE */ 1471 1472 static const struct mm_walk_ops pagemap_ops = { 1473 .pmd_entry = pagemap_pmd_range, 1474 .pte_hole = pagemap_pte_hole, 1475 .hugetlb_entry = pagemap_hugetlb_range, 1476 }; 1477 1478 /* 1479 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1480 * 1481 * For each page in the address space, this file contains one 64-bit entry 1482 * consisting of the following: 1483 * 1484 * Bits 0-54 page frame number (PFN) if present 1485 * Bits 0-4 swap type if swapped 1486 * Bits 5-54 swap offset if swapped 1487 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1488 * Bit 56 page exclusively mapped 1489 * Bits 57-60 zero 1490 * Bit 61 page is file-page or shared-anon 1491 * Bit 62 page swapped 1492 * Bit 63 page present 1493 * 1494 * If the page is not present but in swap, then the PFN contains an 1495 * encoding of the swap file number and the page's offset into the 1496 * swap. Unmapped pages return a null PFN. This allows determining 1497 * precisely which pages are mapped (or in swap) and comparing mapped 1498 * pages between processes. 1499 * 1500 * Efficient users of this interface will use /proc/pid/maps to 1501 * determine which areas of memory are actually mapped and llseek to 1502 * skip over unmapped regions. 1503 */ 1504 static ssize_t pagemap_read(struct file *file, char __user *buf, 1505 size_t count, loff_t *ppos) 1506 { 1507 struct mm_struct *mm = file->private_data; 1508 struct pagemapread pm; 1509 unsigned long src; 1510 unsigned long svpfn; 1511 unsigned long start_vaddr; 1512 unsigned long end_vaddr; 1513 int ret = 0, copied = 0; 1514 1515 if (!mm || !mmget_not_zero(mm)) 1516 goto out; 1517 1518 ret = -EINVAL; 1519 /* file position must be aligned */ 1520 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1521 goto out_mm; 1522 1523 ret = 0; 1524 if (!count) 1525 goto out_mm; 1526 1527 /* do not disclose physical addresses: attack vector */ 1528 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1529 1530 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1531 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1532 ret = -ENOMEM; 1533 if (!pm.buffer) 1534 goto out_mm; 1535 1536 src = *ppos; 1537 svpfn = src / PM_ENTRY_BYTES; 1538 start_vaddr = svpfn << PAGE_SHIFT; 1539 end_vaddr = mm->task_size; 1540 1541 /* watch out for wraparound */ 1542 if (svpfn > mm->task_size >> PAGE_SHIFT) 1543 start_vaddr = end_vaddr; 1544 1545 /* 1546 * The odds are that this will stop walking way 1547 * before end_vaddr, because the length of the 1548 * user buffer is tracked in "pm", and the walk 1549 * will stop when we hit the end of the buffer. 1550 */ 1551 ret = 0; 1552 while (count && (start_vaddr < end_vaddr)) { 1553 int len; 1554 unsigned long end; 1555 1556 pm.pos = 0; 1557 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1558 /* overflow ? */ 1559 if (end < start_vaddr || end > end_vaddr) 1560 end = end_vaddr; 1561 ret = down_read_killable(&mm->mmap_sem); 1562 if (ret) 1563 goto out_free; 1564 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1565 up_read(&mm->mmap_sem); 1566 start_vaddr = end; 1567 1568 len = min(count, PM_ENTRY_BYTES * pm.pos); 1569 if (copy_to_user(buf, pm.buffer, len)) { 1570 ret = -EFAULT; 1571 goto out_free; 1572 } 1573 copied += len; 1574 buf += len; 1575 count -= len; 1576 } 1577 *ppos += copied; 1578 if (!ret || ret == PM_END_OF_BUFFER) 1579 ret = copied; 1580 1581 out_free: 1582 kfree(pm.buffer); 1583 out_mm: 1584 mmput(mm); 1585 out: 1586 return ret; 1587 } 1588 1589 static int pagemap_open(struct inode *inode, struct file *file) 1590 { 1591 struct mm_struct *mm; 1592 1593 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1594 if (IS_ERR(mm)) 1595 return PTR_ERR(mm); 1596 file->private_data = mm; 1597 return 0; 1598 } 1599 1600 static int pagemap_release(struct inode *inode, struct file *file) 1601 { 1602 struct mm_struct *mm = file->private_data; 1603 1604 if (mm) 1605 mmdrop(mm); 1606 return 0; 1607 } 1608 1609 const struct file_operations proc_pagemap_operations = { 1610 .llseek = mem_lseek, /* borrow this */ 1611 .read = pagemap_read, 1612 .open = pagemap_open, 1613 .release = pagemap_release, 1614 }; 1615 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1616 1617 #ifdef CONFIG_NUMA 1618 1619 struct numa_maps { 1620 unsigned long pages; 1621 unsigned long anon; 1622 unsigned long active; 1623 unsigned long writeback; 1624 unsigned long mapcount_max; 1625 unsigned long dirty; 1626 unsigned long swapcache; 1627 unsigned long node[MAX_NUMNODES]; 1628 }; 1629 1630 struct numa_maps_private { 1631 struct proc_maps_private proc_maps; 1632 struct numa_maps md; 1633 }; 1634 1635 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1636 unsigned long nr_pages) 1637 { 1638 int count = page_mapcount(page); 1639 1640 md->pages += nr_pages; 1641 if (pte_dirty || PageDirty(page)) 1642 md->dirty += nr_pages; 1643 1644 if (PageSwapCache(page)) 1645 md->swapcache += nr_pages; 1646 1647 if (PageActive(page) || PageUnevictable(page)) 1648 md->active += nr_pages; 1649 1650 if (PageWriteback(page)) 1651 md->writeback += nr_pages; 1652 1653 if (PageAnon(page)) 1654 md->anon += nr_pages; 1655 1656 if (count > md->mapcount_max) 1657 md->mapcount_max = count; 1658 1659 md->node[page_to_nid(page)] += nr_pages; 1660 } 1661 1662 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1663 unsigned long addr) 1664 { 1665 struct page *page; 1666 int nid; 1667 1668 if (!pte_present(pte)) 1669 return NULL; 1670 1671 page = vm_normal_page(vma, addr, pte); 1672 if (!page) 1673 return NULL; 1674 1675 if (PageReserved(page)) 1676 return NULL; 1677 1678 nid = page_to_nid(page); 1679 if (!node_isset(nid, node_states[N_MEMORY])) 1680 return NULL; 1681 1682 return page; 1683 } 1684 1685 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1686 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1687 struct vm_area_struct *vma, 1688 unsigned long addr) 1689 { 1690 struct page *page; 1691 int nid; 1692 1693 if (!pmd_present(pmd)) 1694 return NULL; 1695 1696 page = vm_normal_page_pmd(vma, addr, pmd); 1697 if (!page) 1698 return NULL; 1699 1700 if (PageReserved(page)) 1701 return NULL; 1702 1703 nid = page_to_nid(page); 1704 if (!node_isset(nid, node_states[N_MEMORY])) 1705 return NULL; 1706 1707 return page; 1708 } 1709 #endif 1710 1711 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1712 unsigned long end, struct mm_walk *walk) 1713 { 1714 struct numa_maps *md = walk->private; 1715 struct vm_area_struct *vma = walk->vma; 1716 spinlock_t *ptl; 1717 pte_t *orig_pte; 1718 pte_t *pte; 1719 1720 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1721 ptl = pmd_trans_huge_lock(pmd, vma); 1722 if (ptl) { 1723 struct page *page; 1724 1725 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1726 if (page) 1727 gather_stats(page, md, pmd_dirty(*pmd), 1728 HPAGE_PMD_SIZE/PAGE_SIZE); 1729 spin_unlock(ptl); 1730 return 0; 1731 } 1732 1733 if (pmd_trans_unstable(pmd)) 1734 return 0; 1735 #endif 1736 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1737 do { 1738 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1739 if (!page) 1740 continue; 1741 gather_stats(page, md, pte_dirty(*pte), 1); 1742 1743 } while (pte++, addr += PAGE_SIZE, addr != end); 1744 pte_unmap_unlock(orig_pte, ptl); 1745 cond_resched(); 1746 return 0; 1747 } 1748 #ifdef CONFIG_HUGETLB_PAGE 1749 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1750 unsigned long addr, unsigned long end, struct mm_walk *walk) 1751 { 1752 pte_t huge_pte = huge_ptep_get(pte); 1753 struct numa_maps *md; 1754 struct page *page; 1755 1756 if (!pte_present(huge_pte)) 1757 return 0; 1758 1759 page = pte_page(huge_pte); 1760 if (!page) 1761 return 0; 1762 1763 md = walk->private; 1764 gather_stats(page, md, pte_dirty(huge_pte), 1); 1765 return 0; 1766 } 1767 1768 #else 1769 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1770 unsigned long addr, unsigned long end, struct mm_walk *walk) 1771 { 1772 return 0; 1773 } 1774 #endif 1775 1776 static const struct mm_walk_ops show_numa_ops = { 1777 .hugetlb_entry = gather_hugetlb_stats, 1778 .pmd_entry = gather_pte_stats, 1779 }; 1780 1781 /* 1782 * Display pages allocated per node and memory policy via /proc. 1783 */ 1784 static int show_numa_map(struct seq_file *m, void *v) 1785 { 1786 struct numa_maps_private *numa_priv = m->private; 1787 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1788 struct vm_area_struct *vma = v; 1789 struct numa_maps *md = &numa_priv->md; 1790 struct file *file = vma->vm_file; 1791 struct mm_struct *mm = vma->vm_mm; 1792 struct mempolicy *pol; 1793 char buffer[64]; 1794 int nid; 1795 1796 if (!mm) 1797 return 0; 1798 1799 /* Ensure we start with an empty set of numa_maps statistics. */ 1800 memset(md, 0, sizeof(*md)); 1801 1802 pol = __get_vma_policy(vma, vma->vm_start); 1803 if (pol) { 1804 mpol_to_str(buffer, sizeof(buffer), pol); 1805 mpol_cond_put(pol); 1806 } else { 1807 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1808 } 1809 1810 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1811 1812 if (file) { 1813 seq_puts(m, " file="); 1814 seq_file_path(m, file, "\n\t= "); 1815 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1816 seq_puts(m, " heap"); 1817 } else if (is_stack(vma)) { 1818 seq_puts(m, " stack"); 1819 } 1820 1821 if (is_vm_hugetlb_page(vma)) 1822 seq_puts(m, " huge"); 1823 1824 /* mmap_sem is held by m_start */ 1825 walk_page_vma(vma, &show_numa_ops, md); 1826 1827 if (!md->pages) 1828 goto out; 1829 1830 if (md->anon) 1831 seq_printf(m, " anon=%lu", md->anon); 1832 1833 if (md->dirty) 1834 seq_printf(m, " dirty=%lu", md->dirty); 1835 1836 if (md->pages != md->anon && md->pages != md->dirty) 1837 seq_printf(m, " mapped=%lu", md->pages); 1838 1839 if (md->mapcount_max > 1) 1840 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1841 1842 if (md->swapcache) 1843 seq_printf(m, " swapcache=%lu", md->swapcache); 1844 1845 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1846 seq_printf(m, " active=%lu", md->active); 1847 1848 if (md->writeback) 1849 seq_printf(m, " writeback=%lu", md->writeback); 1850 1851 for_each_node_state(nid, N_MEMORY) 1852 if (md->node[nid]) 1853 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1854 1855 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1856 out: 1857 seq_putc(m, '\n'); 1858 return 0; 1859 } 1860 1861 static const struct seq_operations proc_pid_numa_maps_op = { 1862 .start = m_start, 1863 .next = m_next, 1864 .stop = m_stop, 1865 .show = show_numa_map, 1866 }; 1867 1868 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1869 { 1870 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1871 sizeof(struct numa_maps_private)); 1872 } 1873 1874 const struct file_operations proc_pid_numa_maps_operations = { 1875 .open = pid_numa_maps_open, 1876 .read = seq_read, 1877 .llseek = seq_lseek, 1878 .release = proc_map_release, 1879 }; 1880 1881 #endif /* CONFIG_NUMA */ 1882