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_pfn_swap_entry(swpent)) 518 page = pfn_swap_entry_to_page(swpent); 519 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 520 && pte_none(*pte))) { 521 page = xa_load(&vma->vm_file->f_mapping->i_pages, 522 linear_page_index(vma, addr)); 523 if (xa_is_value(page)) 524 mss->swap += PAGE_SIZE; 525 return; 526 } 527 528 if (!page) 529 return; 530 531 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked); 532 } 533 534 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 535 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 536 struct mm_walk *walk) 537 { 538 struct mem_size_stats *mss = walk->private; 539 struct vm_area_struct *vma = walk->vma; 540 bool locked = !!(vma->vm_flags & VM_LOCKED); 541 struct page *page = NULL; 542 543 if (pmd_present(*pmd)) { 544 /* FOLL_DUMP will return -EFAULT on huge zero page */ 545 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 546 } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) { 547 swp_entry_t entry = pmd_to_swp_entry(*pmd); 548 549 if (is_migration_entry(entry)) 550 page = pfn_swap_entry_to_page(entry); 551 } 552 if (IS_ERR_OR_NULL(page)) 553 return; 554 if (PageAnon(page)) 555 mss->anonymous_thp += HPAGE_PMD_SIZE; 556 else if (PageSwapBacked(page)) 557 mss->shmem_thp += HPAGE_PMD_SIZE; 558 else if (is_zone_device_page(page)) 559 /* pass */; 560 else 561 mss->file_thp += HPAGE_PMD_SIZE; 562 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked); 563 } 564 #else 565 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 566 struct mm_walk *walk) 567 { 568 } 569 #endif 570 571 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 572 struct mm_walk *walk) 573 { 574 struct vm_area_struct *vma = walk->vma; 575 pte_t *pte; 576 spinlock_t *ptl; 577 578 ptl = pmd_trans_huge_lock(pmd, vma); 579 if (ptl) { 580 smaps_pmd_entry(pmd, addr, walk); 581 spin_unlock(ptl); 582 goto out; 583 } 584 585 if (pmd_trans_unstable(pmd)) 586 goto out; 587 /* 588 * The mmap_lock held all the way back in m_start() is what 589 * keeps khugepaged out of here and from collapsing things 590 * in here. 591 */ 592 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 593 for (; addr != end; pte++, addr += PAGE_SIZE) 594 smaps_pte_entry(pte, addr, walk); 595 pte_unmap_unlock(pte - 1, ptl); 596 out: 597 cond_resched(); 598 return 0; 599 } 600 601 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 602 { 603 /* 604 * Don't forget to update Documentation/ on changes. 605 */ 606 static const char mnemonics[BITS_PER_LONG][2] = { 607 /* 608 * In case if we meet a flag we don't know about. 609 */ 610 [0 ... (BITS_PER_LONG-1)] = "??", 611 612 [ilog2(VM_READ)] = "rd", 613 [ilog2(VM_WRITE)] = "wr", 614 [ilog2(VM_EXEC)] = "ex", 615 [ilog2(VM_SHARED)] = "sh", 616 [ilog2(VM_MAYREAD)] = "mr", 617 [ilog2(VM_MAYWRITE)] = "mw", 618 [ilog2(VM_MAYEXEC)] = "me", 619 [ilog2(VM_MAYSHARE)] = "ms", 620 [ilog2(VM_GROWSDOWN)] = "gd", 621 [ilog2(VM_PFNMAP)] = "pf", 622 [ilog2(VM_LOCKED)] = "lo", 623 [ilog2(VM_IO)] = "io", 624 [ilog2(VM_SEQ_READ)] = "sr", 625 [ilog2(VM_RAND_READ)] = "rr", 626 [ilog2(VM_DONTCOPY)] = "dc", 627 [ilog2(VM_DONTEXPAND)] = "de", 628 [ilog2(VM_ACCOUNT)] = "ac", 629 [ilog2(VM_NORESERVE)] = "nr", 630 [ilog2(VM_HUGETLB)] = "ht", 631 [ilog2(VM_SYNC)] = "sf", 632 [ilog2(VM_ARCH_1)] = "ar", 633 [ilog2(VM_WIPEONFORK)] = "wf", 634 [ilog2(VM_DONTDUMP)] = "dd", 635 #ifdef CONFIG_ARM64_BTI 636 [ilog2(VM_ARM64_BTI)] = "bt", 637 #endif 638 #ifdef CONFIG_MEM_SOFT_DIRTY 639 [ilog2(VM_SOFTDIRTY)] = "sd", 640 #endif 641 [ilog2(VM_MIXEDMAP)] = "mm", 642 [ilog2(VM_HUGEPAGE)] = "hg", 643 [ilog2(VM_NOHUGEPAGE)] = "nh", 644 [ilog2(VM_MERGEABLE)] = "mg", 645 [ilog2(VM_UFFD_MISSING)]= "um", 646 [ilog2(VM_UFFD_WP)] = "uw", 647 #ifdef CONFIG_ARM64_MTE 648 [ilog2(VM_MTE)] = "mt", 649 [ilog2(VM_MTE_ALLOWED)] = "", 650 #endif 651 #ifdef CONFIG_ARCH_HAS_PKEYS 652 /* These come out via ProtectionKey: */ 653 [ilog2(VM_PKEY_BIT0)] = "", 654 [ilog2(VM_PKEY_BIT1)] = "", 655 [ilog2(VM_PKEY_BIT2)] = "", 656 [ilog2(VM_PKEY_BIT3)] = "", 657 #if VM_PKEY_BIT4 658 [ilog2(VM_PKEY_BIT4)] = "", 659 #endif 660 #endif /* CONFIG_ARCH_HAS_PKEYS */ 661 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR 662 [ilog2(VM_UFFD_MINOR)] = "ui", 663 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ 664 }; 665 size_t i; 666 667 seq_puts(m, "VmFlags: "); 668 for (i = 0; i < BITS_PER_LONG; i++) { 669 if (!mnemonics[i][0]) 670 continue; 671 if (vma->vm_flags & (1UL << i)) { 672 seq_putc(m, mnemonics[i][0]); 673 seq_putc(m, mnemonics[i][1]); 674 seq_putc(m, ' '); 675 } 676 } 677 seq_putc(m, '\n'); 678 } 679 680 #ifdef CONFIG_HUGETLB_PAGE 681 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 682 unsigned long addr, unsigned long end, 683 struct mm_walk *walk) 684 { 685 struct mem_size_stats *mss = walk->private; 686 struct vm_area_struct *vma = walk->vma; 687 struct page *page = NULL; 688 689 if (pte_present(*pte)) { 690 page = vm_normal_page(vma, addr, *pte); 691 } else if (is_swap_pte(*pte)) { 692 swp_entry_t swpent = pte_to_swp_entry(*pte); 693 694 if (is_pfn_swap_entry(swpent)) 695 page = pfn_swap_entry_to_page(swpent); 696 } 697 if (page) { 698 int mapcount = page_mapcount(page); 699 700 if (mapcount >= 2) 701 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 702 else 703 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 704 } 705 return 0; 706 } 707 #else 708 #define smaps_hugetlb_range NULL 709 #endif /* HUGETLB_PAGE */ 710 711 static const struct mm_walk_ops smaps_walk_ops = { 712 .pmd_entry = smaps_pte_range, 713 .hugetlb_entry = smaps_hugetlb_range, 714 }; 715 716 static const struct mm_walk_ops smaps_shmem_walk_ops = { 717 .pmd_entry = smaps_pte_range, 718 .hugetlb_entry = smaps_hugetlb_range, 719 .pte_hole = smaps_pte_hole, 720 }; 721 722 /* 723 * Gather mem stats from @vma with the indicated beginning 724 * address @start, and keep them in @mss. 725 * 726 * Use vm_start of @vma as the beginning address if @start is 0. 727 */ 728 static void smap_gather_stats(struct vm_area_struct *vma, 729 struct mem_size_stats *mss, unsigned long start) 730 { 731 const struct mm_walk_ops *ops = &smaps_walk_ops; 732 733 /* Invalid start */ 734 if (start >= vma->vm_end) 735 return; 736 737 #ifdef CONFIG_SHMEM 738 /* In case of smaps_rollup, reset the value from previous vma */ 739 mss->check_shmem_swap = false; 740 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 741 /* 742 * For shared or readonly shmem mappings we know that all 743 * swapped out pages belong to the shmem object, and we can 744 * obtain the swap value much more efficiently. For private 745 * writable mappings, we might have COW pages that are 746 * not affected by the parent swapped out pages of the shmem 747 * object, so we have to distinguish them during the page walk. 748 * Unless we know that the shmem object (or the part mapped by 749 * our VMA) has no swapped out pages at all. 750 */ 751 unsigned long shmem_swapped = shmem_swap_usage(vma); 752 753 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 754 !(vma->vm_flags & VM_WRITE))) { 755 mss->swap += shmem_swapped; 756 } else { 757 mss->check_shmem_swap = true; 758 ops = &smaps_shmem_walk_ops; 759 } 760 } 761 #endif 762 /* mmap_lock is held in m_start */ 763 if (!start) 764 walk_page_vma(vma, ops, mss); 765 else 766 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); 767 } 768 769 #define SEQ_PUT_DEC(str, val) \ 770 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 771 772 /* Show the contents common for smaps and smaps_rollup */ 773 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 774 bool rollup_mode) 775 { 776 SEQ_PUT_DEC("Rss: ", mss->resident); 777 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 778 if (rollup_mode) { 779 /* 780 * These are meaningful only for smaps_rollup, otherwise two of 781 * them are zero, and the other one is the same as Pss. 782 */ 783 SEQ_PUT_DEC(" kB\nPss_Anon: ", 784 mss->pss_anon >> PSS_SHIFT); 785 SEQ_PUT_DEC(" kB\nPss_File: ", 786 mss->pss_file >> PSS_SHIFT); 787 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 788 mss->pss_shmem >> PSS_SHIFT); 789 } 790 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 791 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 792 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 793 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 794 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 795 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 796 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 797 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 798 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 799 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 800 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 801 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 802 mss->private_hugetlb >> 10, 7); 803 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 804 SEQ_PUT_DEC(" kB\nSwapPss: ", 805 mss->swap_pss >> PSS_SHIFT); 806 SEQ_PUT_DEC(" kB\nLocked: ", 807 mss->pss_locked >> PSS_SHIFT); 808 seq_puts(m, " kB\n"); 809 } 810 811 static int show_smap(struct seq_file *m, void *v) 812 { 813 struct vm_area_struct *vma = v; 814 struct mem_size_stats mss; 815 816 memset(&mss, 0, sizeof(mss)); 817 818 smap_gather_stats(vma, &mss, 0); 819 820 show_map_vma(m, vma); 821 822 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 823 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 824 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 825 seq_puts(m, " kB\n"); 826 827 __show_smap(m, &mss, false); 828 829 seq_printf(m, "THPeligible: %d\n", 830 transparent_hugepage_active(vma)); 831 832 if (arch_pkeys_enabled()) 833 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 834 show_smap_vma_flags(m, vma); 835 836 return 0; 837 } 838 839 static int show_smaps_rollup(struct seq_file *m, void *v) 840 { 841 struct proc_maps_private *priv = m->private; 842 struct mem_size_stats mss; 843 struct mm_struct *mm; 844 struct vm_area_struct *vma; 845 unsigned long last_vma_end = 0; 846 int ret = 0; 847 848 priv->task = get_proc_task(priv->inode); 849 if (!priv->task) 850 return -ESRCH; 851 852 mm = priv->mm; 853 if (!mm || !mmget_not_zero(mm)) { 854 ret = -ESRCH; 855 goto out_put_task; 856 } 857 858 memset(&mss, 0, sizeof(mss)); 859 860 ret = mmap_read_lock_killable(mm); 861 if (ret) 862 goto out_put_mm; 863 864 hold_task_mempolicy(priv); 865 866 for (vma = priv->mm->mmap; vma;) { 867 smap_gather_stats(vma, &mss, 0); 868 last_vma_end = vma->vm_end; 869 870 /* 871 * Release mmap_lock temporarily if someone wants to 872 * access it for write request. 873 */ 874 if (mmap_lock_is_contended(mm)) { 875 mmap_read_unlock(mm); 876 ret = mmap_read_lock_killable(mm); 877 if (ret) { 878 release_task_mempolicy(priv); 879 goto out_put_mm; 880 } 881 882 /* 883 * After dropping the lock, there are four cases to 884 * consider. See the following example for explanation. 885 * 886 * +------+------+-----------+ 887 * | VMA1 | VMA2 | VMA3 | 888 * +------+------+-----------+ 889 * | | | | 890 * 4k 8k 16k 400k 891 * 892 * Suppose we drop the lock after reading VMA2 due to 893 * contention, then we get: 894 * 895 * last_vma_end = 16k 896 * 897 * 1) VMA2 is freed, but VMA3 exists: 898 * 899 * find_vma(mm, 16k - 1) will return VMA3. 900 * In this case, just continue from VMA3. 901 * 902 * 2) VMA2 still exists: 903 * 904 * find_vma(mm, 16k - 1) will return VMA2. 905 * Iterate the loop like the original one. 906 * 907 * 3) No more VMAs can be found: 908 * 909 * find_vma(mm, 16k - 1) will return NULL. 910 * No more things to do, just break. 911 * 912 * 4) (last_vma_end - 1) is the middle of a vma (VMA'): 913 * 914 * find_vma(mm, 16k - 1) will return VMA' whose range 915 * contains last_vma_end. 916 * Iterate VMA' from last_vma_end. 917 */ 918 vma = find_vma(mm, last_vma_end - 1); 919 /* Case 3 above */ 920 if (!vma) 921 break; 922 923 /* Case 1 above */ 924 if (vma->vm_start >= last_vma_end) 925 continue; 926 927 /* Case 4 above */ 928 if (vma->vm_end > last_vma_end) 929 smap_gather_stats(vma, &mss, last_vma_end); 930 } 931 /* Case 2 above */ 932 vma = vma->vm_next; 933 } 934 935 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 936 last_vma_end, 0, 0, 0, 0); 937 seq_pad(m, ' '); 938 seq_puts(m, "[rollup]\n"); 939 940 __show_smap(m, &mss, true); 941 942 release_task_mempolicy(priv); 943 mmap_read_unlock(mm); 944 945 out_put_mm: 946 mmput(mm); 947 out_put_task: 948 put_task_struct(priv->task); 949 priv->task = NULL; 950 951 return ret; 952 } 953 #undef SEQ_PUT_DEC 954 955 static const struct seq_operations proc_pid_smaps_op = { 956 .start = m_start, 957 .next = m_next, 958 .stop = m_stop, 959 .show = show_smap 960 }; 961 962 static int pid_smaps_open(struct inode *inode, struct file *file) 963 { 964 return do_maps_open(inode, file, &proc_pid_smaps_op); 965 } 966 967 static int smaps_rollup_open(struct inode *inode, struct file *file) 968 { 969 int ret; 970 struct proc_maps_private *priv; 971 972 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 973 if (!priv) 974 return -ENOMEM; 975 976 ret = single_open(file, show_smaps_rollup, priv); 977 if (ret) 978 goto out_free; 979 980 priv->inode = inode; 981 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 982 if (IS_ERR(priv->mm)) { 983 ret = PTR_ERR(priv->mm); 984 985 single_release(inode, file); 986 goto out_free; 987 } 988 989 return 0; 990 991 out_free: 992 kfree(priv); 993 return ret; 994 } 995 996 static int smaps_rollup_release(struct inode *inode, struct file *file) 997 { 998 struct seq_file *seq = file->private_data; 999 struct proc_maps_private *priv = seq->private; 1000 1001 if (priv->mm) 1002 mmdrop(priv->mm); 1003 1004 kfree(priv); 1005 return single_release(inode, file); 1006 } 1007 1008 const struct file_operations proc_pid_smaps_operations = { 1009 .open = pid_smaps_open, 1010 .read = seq_read, 1011 .llseek = seq_lseek, 1012 .release = proc_map_release, 1013 }; 1014 1015 const struct file_operations proc_pid_smaps_rollup_operations = { 1016 .open = smaps_rollup_open, 1017 .read = seq_read, 1018 .llseek = seq_lseek, 1019 .release = smaps_rollup_release, 1020 }; 1021 1022 enum clear_refs_types { 1023 CLEAR_REFS_ALL = 1, 1024 CLEAR_REFS_ANON, 1025 CLEAR_REFS_MAPPED, 1026 CLEAR_REFS_SOFT_DIRTY, 1027 CLEAR_REFS_MM_HIWATER_RSS, 1028 CLEAR_REFS_LAST, 1029 }; 1030 1031 struct clear_refs_private { 1032 enum clear_refs_types type; 1033 }; 1034 1035 #ifdef CONFIG_MEM_SOFT_DIRTY 1036 1037 static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1038 { 1039 struct page *page; 1040 1041 if (!pte_write(pte)) 1042 return false; 1043 if (!is_cow_mapping(vma->vm_flags)) 1044 return false; 1045 if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))) 1046 return false; 1047 page = vm_normal_page(vma, addr, pte); 1048 if (!page) 1049 return false; 1050 return page_maybe_dma_pinned(page); 1051 } 1052 1053 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1054 unsigned long addr, pte_t *pte) 1055 { 1056 /* 1057 * The soft-dirty tracker uses #PF-s to catch writes 1058 * to pages, so write-protect the pte as well. See the 1059 * Documentation/admin-guide/mm/soft-dirty.rst for full description 1060 * of how soft-dirty works. 1061 */ 1062 pte_t ptent = *pte; 1063 1064 if (pte_present(ptent)) { 1065 pte_t old_pte; 1066 1067 if (pte_is_pinned(vma, addr, ptent)) 1068 return; 1069 old_pte = ptep_modify_prot_start(vma, addr, pte); 1070 ptent = pte_wrprotect(old_pte); 1071 ptent = pte_clear_soft_dirty(ptent); 1072 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1073 } else if (is_swap_pte(ptent)) { 1074 ptent = pte_swp_clear_soft_dirty(ptent); 1075 set_pte_at(vma->vm_mm, addr, pte, ptent); 1076 } 1077 } 1078 #else 1079 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1080 unsigned long addr, pte_t *pte) 1081 { 1082 } 1083 #endif 1084 1085 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 1086 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1087 unsigned long addr, pmd_t *pmdp) 1088 { 1089 pmd_t old, pmd = *pmdp; 1090 1091 if (pmd_present(pmd)) { 1092 /* See comment in change_huge_pmd() */ 1093 old = pmdp_invalidate(vma, addr, pmdp); 1094 if (pmd_dirty(old)) 1095 pmd = pmd_mkdirty(pmd); 1096 if (pmd_young(old)) 1097 pmd = pmd_mkyoung(pmd); 1098 1099 pmd = pmd_wrprotect(pmd); 1100 pmd = pmd_clear_soft_dirty(pmd); 1101 1102 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1103 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1104 pmd = pmd_swp_clear_soft_dirty(pmd); 1105 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1106 } 1107 } 1108 #else 1109 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1110 unsigned long addr, pmd_t *pmdp) 1111 { 1112 } 1113 #endif 1114 1115 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1116 unsigned long end, struct mm_walk *walk) 1117 { 1118 struct clear_refs_private *cp = walk->private; 1119 struct vm_area_struct *vma = walk->vma; 1120 pte_t *pte, ptent; 1121 spinlock_t *ptl; 1122 struct page *page; 1123 1124 ptl = pmd_trans_huge_lock(pmd, vma); 1125 if (ptl) { 1126 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1127 clear_soft_dirty_pmd(vma, addr, pmd); 1128 goto out; 1129 } 1130 1131 if (!pmd_present(*pmd)) 1132 goto out; 1133 1134 page = pmd_page(*pmd); 1135 1136 /* Clear accessed and referenced bits. */ 1137 pmdp_test_and_clear_young(vma, addr, pmd); 1138 test_and_clear_page_young(page); 1139 ClearPageReferenced(page); 1140 out: 1141 spin_unlock(ptl); 1142 return 0; 1143 } 1144 1145 if (pmd_trans_unstable(pmd)) 1146 return 0; 1147 1148 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1149 for (; addr != end; pte++, addr += PAGE_SIZE) { 1150 ptent = *pte; 1151 1152 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1153 clear_soft_dirty(vma, addr, pte); 1154 continue; 1155 } 1156 1157 if (!pte_present(ptent)) 1158 continue; 1159 1160 page = vm_normal_page(vma, addr, ptent); 1161 if (!page) 1162 continue; 1163 1164 /* Clear accessed and referenced bits. */ 1165 ptep_test_and_clear_young(vma, addr, pte); 1166 test_and_clear_page_young(page); 1167 ClearPageReferenced(page); 1168 } 1169 pte_unmap_unlock(pte - 1, ptl); 1170 cond_resched(); 1171 return 0; 1172 } 1173 1174 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1175 struct mm_walk *walk) 1176 { 1177 struct clear_refs_private *cp = walk->private; 1178 struct vm_area_struct *vma = walk->vma; 1179 1180 if (vma->vm_flags & VM_PFNMAP) 1181 return 1; 1182 1183 /* 1184 * Writing 1 to /proc/pid/clear_refs affects all pages. 1185 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1186 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1187 * Writing 4 to /proc/pid/clear_refs affects all pages. 1188 */ 1189 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1190 return 1; 1191 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1192 return 1; 1193 return 0; 1194 } 1195 1196 static const struct mm_walk_ops clear_refs_walk_ops = { 1197 .pmd_entry = clear_refs_pte_range, 1198 .test_walk = clear_refs_test_walk, 1199 }; 1200 1201 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1202 size_t count, loff_t *ppos) 1203 { 1204 struct task_struct *task; 1205 char buffer[PROC_NUMBUF]; 1206 struct mm_struct *mm; 1207 struct vm_area_struct *vma; 1208 enum clear_refs_types type; 1209 int itype; 1210 int rv; 1211 1212 memset(buffer, 0, sizeof(buffer)); 1213 if (count > sizeof(buffer) - 1) 1214 count = sizeof(buffer) - 1; 1215 if (copy_from_user(buffer, buf, count)) 1216 return -EFAULT; 1217 rv = kstrtoint(strstrip(buffer), 10, &itype); 1218 if (rv < 0) 1219 return rv; 1220 type = (enum clear_refs_types)itype; 1221 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1222 return -EINVAL; 1223 1224 task = get_proc_task(file_inode(file)); 1225 if (!task) 1226 return -ESRCH; 1227 mm = get_task_mm(task); 1228 if (mm) { 1229 struct mmu_notifier_range range; 1230 struct clear_refs_private cp = { 1231 .type = type, 1232 }; 1233 1234 if (mmap_write_lock_killable(mm)) { 1235 count = -EINTR; 1236 goto out_mm; 1237 } 1238 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1239 /* 1240 * Writing 5 to /proc/pid/clear_refs resets the peak 1241 * resident set size to this mm's current rss value. 1242 */ 1243 reset_mm_hiwater_rss(mm); 1244 goto out_unlock; 1245 } 1246 1247 if (type == CLEAR_REFS_SOFT_DIRTY) { 1248 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1249 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1250 continue; 1251 vma->vm_flags &= ~VM_SOFTDIRTY; 1252 vma_set_page_prot(vma); 1253 } 1254 1255 inc_tlb_flush_pending(mm); 1256 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1257 0, NULL, mm, 0, -1UL); 1258 mmu_notifier_invalidate_range_start(&range); 1259 } 1260 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1261 &cp); 1262 if (type == CLEAR_REFS_SOFT_DIRTY) { 1263 mmu_notifier_invalidate_range_end(&range); 1264 flush_tlb_mm(mm); 1265 dec_tlb_flush_pending(mm); 1266 } 1267 out_unlock: 1268 mmap_write_unlock(mm); 1269 out_mm: 1270 mmput(mm); 1271 } 1272 put_task_struct(task); 1273 1274 return count; 1275 } 1276 1277 const struct file_operations proc_clear_refs_operations = { 1278 .write = clear_refs_write, 1279 .llseek = noop_llseek, 1280 }; 1281 1282 typedef struct { 1283 u64 pme; 1284 } pagemap_entry_t; 1285 1286 struct pagemapread { 1287 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1288 pagemap_entry_t *buffer; 1289 bool show_pfn; 1290 }; 1291 1292 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1293 #define PAGEMAP_WALK_MASK (PMD_MASK) 1294 1295 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1296 #define PM_PFRAME_BITS 55 1297 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1298 #define PM_SOFT_DIRTY BIT_ULL(55) 1299 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1300 #define PM_UFFD_WP BIT_ULL(57) 1301 #define PM_FILE BIT_ULL(61) 1302 #define PM_SWAP BIT_ULL(62) 1303 #define PM_PRESENT BIT_ULL(63) 1304 1305 #define PM_END_OF_BUFFER 1 1306 1307 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1308 { 1309 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1310 } 1311 1312 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1313 struct pagemapread *pm) 1314 { 1315 pm->buffer[pm->pos++] = *pme; 1316 if (pm->pos >= pm->len) 1317 return PM_END_OF_BUFFER; 1318 return 0; 1319 } 1320 1321 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1322 __always_unused int depth, struct mm_walk *walk) 1323 { 1324 struct pagemapread *pm = walk->private; 1325 unsigned long addr = start; 1326 int err = 0; 1327 1328 while (addr < end) { 1329 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1330 pagemap_entry_t pme = make_pme(0, 0); 1331 /* End of address space hole, which we mark as non-present. */ 1332 unsigned long hole_end; 1333 1334 if (vma) 1335 hole_end = min(end, vma->vm_start); 1336 else 1337 hole_end = end; 1338 1339 for (; addr < hole_end; addr += PAGE_SIZE) { 1340 err = add_to_pagemap(addr, &pme, pm); 1341 if (err) 1342 goto out; 1343 } 1344 1345 if (!vma) 1346 break; 1347 1348 /* Addresses in the VMA. */ 1349 if (vma->vm_flags & VM_SOFTDIRTY) 1350 pme = make_pme(0, PM_SOFT_DIRTY); 1351 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1352 err = add_to_pagemap(addr, &pme, pm); 1353 if (err) 1354 goto out; 1355 } 1356 } 1357 out: 1358 return err; 1359 } 1360 1361 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1362 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1363 { 1364 u64 frame = 0, flags = 0; 1365 struct page *page = NULL; 1366 1367 if (pte_present(pte)) { 1368 if (pm->show_pfn) 1369 frame = pte_pfn(pte); 1370 flags |= PM_PRESENT; 1371 page = vm_normal_page(vma, addr, pte); 1372 if (pte_soft_dirty(pte)) 1373 flags |= PM_SOFT_DIRTY; 1374 if (pte_uffd_wp(pte)) 1375 flags |= PM_UFFD_WP; 1376 } else if (is_swap_pte(pte)) { 1377 swp_entry_t entry; 1378 if (pte_swp_soft_dirty(pte)) 1379 flags |= PM_SOFT_DIRTY; 1380 if (pte_swp_uffd_wp(pte)) 1381 flags |= PM_UFFD_WP; 1382 entry = pte_to_swp_entry(pte); 1383 if (pm->show_pfn) 1384 frame = swp_type(entry) | 1385 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1386 flags |= PM_SWAP; 1387 if (is_pfn_swap_entry(entry)) 1388 page = pfn_swap_entry_to_page(entry); 1389 } 1390 1391 if (page && !PageAnon(page)) 1392 flags |= PM_FILE; 1393 if (page && page_mapcount(page) == 1) 1394 flags |= PM_MMAP_EXCLUSIVE; 1395 if (vma->vm_flags & VM_SOFTDIRTY) 1396 flags |= PM_SOFT_DIRTY; 1397 1398 return make_pme(frame, flags); 1399 } 1400 1401 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1402 struct mm_walk *walk) 1403 { 1404 struct vm_area_struct *vma = walk->vma; 1405 struct pagemapread *pm = walk->private; 1406 spinlock_t *ptl; 1407 pte_t *pte, *orig_pte; 1408 int err = 0; 1409 1410 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1411 ptl = pmd_trans_huge_lock(pmdp, vma); 1412 if (ptl) { 1413 u64 flags = 0, frame = 0; 1414 pmd_t pmd = *pmdp; 1415 struct page *page = NULL; 1416 1417 if (vma->vm_flags & VM_SOFTDIRTY) 1418 flags |= PM_SOFT_DIRTY; 1419 1420 if (pmd_present(pmd)) { 1421 page = pmd_page(pmd); 1422 1423 flags |= PM_PRESENT; 1424 if (pmd_soft_dirty(pmd)) 1425 flags |= PM_SOFT_DIRTY; 1426 if (pmd_uffd_wp(pmd)) 1427 flags |= PM_UFFD_WP; 1428 if (pm->show_pfn) 1429 frame = pmd_pfn(pmd) + 1430 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1431 } 1432 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1433 else if (is_swap_pmd(pmd)) { 1434 swp_entry_t entry = pmd_to_swp_entry(pmd); 1435 unsigned long offset; 1436 1437 if (pm->show_pfn) { 1438 offset = swp_offset(entry) + 1439 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1440 frame = swp_type(entry) | 1441 (offset << MAX_SWAPFILES_SHIFT); 1442 } 1443 flags |= PM_SWAP; 1444 if (pmd_swp_soft_dirty(pmd)) 1445 flags |= PM_SOFT_DIRTY; 1446 if (pmd_swp_uffd_wp(pmd)) 1447 flags |= PM_UFFD_WP; 1448 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1449 page = pfn_swap_entry_to_page(entry); 1450 } 1451 #endif 1452 1453 if (page && page_mapcount(page) == 1) 1454 flags |= PM_MMAP_EXCLUSIVE; 1455 1456 for (; addr != end; addr += PAGE_SIZE) { 1457 pagemap_entry_t pme = make_pme(frame, flags); 1458 1459 err = add_to_pagemap(addr, &pme, pm); 1460 if (err) 1461 break; 1462 if (pm->show_pfn) { 1463 if (flags & PM_PRESENT) 1464 frame++; 1465 else if (flags & PM_SWAP) 1466 frame += (1 << MAX_SWAPFILES_SHIFT); 1467 } 1468 } 1469 spin_unlock(ptl); 1470 return err; 1471 } 1472 1473 if (pmd_trans_unstable(pmdp)) 1474 return 0; 1475 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1476 1477 /* 1478 * We can assume that @vma always points to a valid one and @end never 1479 * goes beyond vma->vm_end. 1480 */ 1481 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1482 for (; addr < end; pte++, addr += PAGE_SIZE) { 1483 pagemap_entry_t pme; 1484 1485 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1486 err = add_to_pagemap(addr, &pme, pm); 1487 if (err) 1488 break; 1489 } 1490 pte_unmap_unlock(orig_pte, ptl); 1491 1492 cond_resched(); 1493 1494 return err; 1495 } 1496 1497 #ifdef CONFIG_HUGETLB_PAGE 1498 /* This function walks within one hugetlb entry in the single call */ 1499 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1500 unsigned long addr, unsigned long end, 1501 struct mm_walk *walk) 1502 { 1503 struct pagemapread *pm = walk->private; 1504 struct vm_area_struct *vma = walk->vma; 1505 u64 flags = 0, frame = 0; 1506 int err = 0; 1507 pte_t pte; 1508 1509 if (vma->vm_flags & VM_SOFTDIRTY) 1510 flags |= PM_SOFT_DIRTY; 1511 1512 pte = huge_ptep_get(ptep); 1513 if (pte_present(pte)) { 1514 struct page *page = pte_page(pte); 1515 1516 if (!PageAnon(page)) 1517 flags |= PM_FILE; 1518 1519 if (page_mapcount(page) == 1) 1520 flags |= PM_MMAP_EXCLUSIVE; 1521 1522 flags |= PM_PRESENT; 1523 if (pm->show_pfn) 1524 frame = pte_pfn(pte) + 1525 ((addr & ~hmask) >> PAGE_SHIFT); 1526 } 1527 1528 for (; addr != end; addr += PAGE_SIZE) { 1529 pagemap_entry_t pme = make_pme(frame, flags); 1530 1531 err = add_to_pagemap(addr, &pme, pm); 1532 if (err) 1533 return err; 1534 if (pm->show_pfn && (flags & PM_PRESENT)) 1535 frame++; 1536 } 1537 1538 cond_resched(); 1539 1540 return err; 1541 } 1542 #else 1543 #define pagemap_hugetlb_range NULL 1544 #endif /* HUGETLB_PAGE */ 1545 1546 static const struct mm_walk_ops pagemap_ops = { 1547 .pmd_entry = pagemap_pmd_range, 1548 .pte_hole = pagemap_pte_hole, 1549 .hugetlb_entry = pagemap_hugetlb_range, 1550 }; 1551 1552 /* 1553 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1554 * 1555 * For each page in the address space, this file contains one 64-bit entry 1556 * consisting of the following: 1557 * 1558 * Bits 0-54 page frame number (PFN) if present 1559 * Bits 0-4 swap type if swapped 1560 * Bits 5-54 swap offset if swapped 1561 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1562 * Bit 56 page exclusively mapped 1563 * Bits 57-60 zero 1564 * Bit 61 page is file-page or shared-anon 1565 * Bit 62 page swapped 1566 * Bit 63 page present 1567 * 1568 * If the page is not present but in swap, then the PFN contains an 1569 * encoding of the swap file number and the page's offset into the 1570 * swap. Unmapped pages return a null PFN. This allows determining 1571 * precisely which pages are mapped (or in swap) and comparing mapped 1572 * pages between processes. 1573 * 1574 * Efficient users of this interface will use /proc/pid/maps to 1575 * determine which areas of memory are actually mapped and llseek to 1576 * skip over unmapped regions. 1577 */ 1578 static ssize_t pagemap_read(struct file *file, char __user *buf, 1579 size_t count, loff_t *ppos) 1580 { 1581 struct mm_struct *mm = file->private_data; 1582 struct pagemapread pm; 1583 unsigned long src; 1584 unsigned long svpfn; 1585 unsigned long start_vaddr; 1586 unsigned long end_vaddr; 1587 int ret = 0, copied = 0; 1588 1589 if (!mm || !mmget_not_zero(mm)) 1590 goto out; 1591 1592 ret = -EINVAL; 1593 /* file position must be aligned */ 1594 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1595 goto out_mm; 1596 1597 ret = 0; 1598 if (!count) 1599 goto out_mm; 1600 1601 /* do not disclose physical addresses: attack vector */ 1602 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1603 1604 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1605 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1606 ret = -ENOMEM; 1607 if (!pm.buffer) 1608 goto out_mm; 1609 1610 src = *ppos; 1611 svpfn = src / PM_ENTRY_BYTES; 1612 end_vaddr = mm->task_size; 1613 1614 /* watch out for wraparound */ 1615 start_vaddr = end_vaddr; 1616 if (svpfn <= (ULONG_MAX >> PAGE_SHIFT)) 1617 start_vaddr = untagged_addr(svpfn << PAGE_SHIFT); 1618 1619 /* Ensure the address is inside the task */ 1620 if (start_vaddr > mm->task_size) 1621 start_vaddr = end_vaddr; 1622 1623 /* 1624 * The odds are that this will stop walking way 1625 * before end_vaddr, because the length of the 1626 * user buffer is tracked in "pm", and the walk 1627 * will stop when we hit the end of the buffer. 1628 */ 1629 ret = 0; 1630 while (count && (start_vaddr < end_vaddr)) { 1631 int len; 1632 unsigned long end; 1633 1634 pm.pos = 0; 1635 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1636 /* overflow ? */ 1637 if (end < start_vaddr || end > end_vaddr) 1638 end = end_vaddr; 1639 ret = mmap_read_lock_killable(mm); 1640 if (ret) 1641 goto out_free; 1642 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1643 mmap_read_unlock(mm); 1644 start_vaddr = end; 1645 1646 len = min(count, PM_ENTRY_BYTES * pm.pos); 1647 if (copy_to_user(buf, pm.buffer, len)) { 1648 ret = -EFAULT; 1649 goto out_free; 1650 } 1651 copied += len; 1652 buf += len; 1653 count -= len; 1654 } 1655 *ppos += copied; 1656 if (!ret || ret == PM_END_OF_BUFFER) 1657 ret = copied; 1658 1659 out_free: 1660 kfree(pm.buffer); 1661 out_mm: 1662 mmput(mm); 1663 out: 1664 return ret; 1665 } 1666 1667 static int pagemap_open(struct inode *inode, struct file *file) 1668 { 1669 struct mm_struct *mm; 1670 1671 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1672 if (IS_ERR(mm)) 1673 return PTR_ERR(mm); 1674 file->private_data = mm; 1675 return 0; 1676 } 1677 1678 static int pagemap_release(struct inode *inode, struct file *file) 1679 { 1680 struct mm_struct *mm = file->private_data; 1681 1682 if (mm) 1683 mmdrop(mm); 1684 return 0; 1685 } 1686 1687 const struct file_operations proc_pagemap_operations = { 1688 .llseek = mem_lseek, /* borrow this */ 1689 .read = pagemap_read, 1690 .open = pagemap_open, 1691 .release = pagemap_release, 1692 }; 1693 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1694 1695 #ifdef CONFIG_NUMA 1696 1697 struct numa_maps { 1698 unsigned long pages; 1699 unsigned long anon; 1700 unsigned long active; 1701 unsigned long writeback; 1702 unsigned long mapcount_max; 1703 unsigned long dirty; 1704 unsigned long swapcache; 1705 unsigned long node[MAX_NUMNODES]; 1706 }; 1707 1708 struct numa_maps_private { 1709 struct proc_maps_private proc_maps; 1710 struct numa_maps md; 1711 }; 1712 1713 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1714 unsigned long nr_pages) 1715 { 1716 int count = page_mapcount(page); 1717 1718 md->pages += nr_pages; 1719 if (pte_dirty || PageDirty(page)) 1720 md->dirty += nr_pages; 1721 1722 if (PageSwapCache(page)) 1723 md->swapcache += nr_pages; 1724 1725 if (PageActive(page) || PageUnevictable(page)) 1726 md->active += nr_pages; 1727 1728 if (PageWriteback(page)) 1729 md->writeback += nr_pages; 1730 1731 if (PageAnon(page)) 1732 md->anon += nr_pages; 1733 1734 if (count > md->mapcount_max) 1735 md->mapcount_max = count; 1736 1737 md->node[page_to_nid(page)] += nr_pages; 1738 } 1739 1740 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1741 unsigned long addr) 1742 { 1743 struct page *page; 1744 int nid; 1745 1746 if (!pte_present(pte)) 1747 return NULL; 1748 1749 page = vm_normal_page(vma, addr, pte); 1750 if (!page) 1751 return NULL; 1752 1753 if (PageReserved(page)) 1754 return NULL; 1755 1756 nid = page_to_nid(page); 1757 if (!node_isset(nid, node_states[N_MEMORY])) 1758 return NULL; 1759 1760 return page; 1761 } 1762 1763 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1764 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1765 struct vm_area_struct *vma, 1766 unsigned long addr) 1767 { 1768 struct page *page; 1769 int nid; 1770 1771 if (!pmd_present(pmd)) 1772 return NULL; 1773 1774 page = vm_normal_page_pmd(vma, addr, pmd); 1775 if (!page) 1776 return NULL; 1777 1778 if (PageReserved(page)) 1779 return NULL; 1780 1781 nid = page_to_nid(page); 1782 if (!node_isset(nid, node_states[N_MEMORY])) 1783 return NULL; 1784 1785 return page; 1786 } 1787 #endif 1788 1789 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1790 unsigned long end, struct mm_walk *walk) 1791 { 1792 struct numa_maps *md = walk->private; 1793 struct vm_area_struct *vma = walk->vma; 1794 spinlock_t *ptl; 1795 pte_t *orig_pte; 1796 pte_t *pte; 1797 1798 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1799 ptl = pmd_trans_huge_lock(pmd, vma); 1800 if (ptl) { 1801 struct page *page; 1802 1803 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1804 if (page) 1805 gather_stats(page, md, pmd_dirty(*pmd), 1806 HPAGE_PMD_SIZE/PAGE_SIZE); 1807 spin_unlock(ptl); 1808 return 0; 1809 } 1810 1811 if (pmd_trans_unstable(pmd)) 1812 return 0; 1813 #endif 1814 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1815 do { 1816 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1817 if (!page) 1818 continue; 1819 gather_stats(page, md, pte_dirty(*pte), 1); 1820 1821 } while (pte++, addr += PAGE_SIZE, addr != end); 1822 pte_unmap_unlock(orig_pte, ptl); 1823 cond_resched(); 1824 return 0; 1825 } 1826 #ifdef CONFIG_HUGETLB_PAGE 1827 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1828 unsigned long addr, unsigned long end, struct mm_walk *walk) 1829 { 1830 pte_t huge_pte = huge_ptep_get(pte); 1831 struct numa_maps *md; 1832 struct page *page; 1833 1834 if (!pte_present(huge_pte)) 1835 return 0; 1836 1837 page = pte_page(huge_pte); 1838 if (!page) 1839 return 0; 1840 1841 md = walk->private; 1842 gather_stats(page, md, pte_dirty(huge_pte), 1); 1843 return 0; 1844 } 1845 1846 #else 1847 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1848 unsigned long addr, unsigned long end, struct mm_walk *walk) 1849 { 1850 return 0; 1851 } 1852 #endif 1853 1854 static const struct mm_walk_ops show_numa_ops = { 1855 .hugetlb_entry = gather_hugetlb_stats, 1856 .pmd_entry = gather_pte_stats, 1857 }; 1858 1859 /* 1860 * Display pages allocated per node and memory policy via /proc. 1861 */ 1862 static int show_numa_map(struct seq_file *m, void *v) 1863 { 1864 struct numa_maps_private *numa_priv = m->private; 1865 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1866 struct vm_area_struct *vma = v; 1867 struct numa_maps *md = &numa_priv->md; 1868 struct file *file = vma->vm_file; 1869 struct mm_struct *mm = vma->vm_mm; 1870 struct mempolicy *pol; 1871 char buffer[64]; 1872 int nid; 1873 1874 if (!mm) 1875 return 0; 1876 1877 /* Ensure we start with an empty set of numa_maps statistics. */ 1878 memset(md, 0, sizeof(*md)); 1879 1880 pol = __get_vma_policy(vma, vma->vm_start); 1881 if (pol) { 1882 mpol_to_str(buffer, sizeof(buffer), pol); 1883 mpol_cond_put(pol); 1884 } else { 1885 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1886 } 1887 1888 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1889 1890 if (file) { 1891 seq_puts(m, " file="); 1892 seq_file_path(m, file, "\n\t= "); 1893 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1894 seq_puts(m, " heap"); 1895 } else if (is_stack(vma)) { 1896 seq_puts(m, " stack"); 1897 } 1898 1899 if (is_vm_hugetlb_page(vma)) 1900 seq_puts(m, " huge"); 1901 1902 /* mmap_lock is held by m_start */ 1903 walk_page_vma(vma, &show_numa_ops, md); 1904 1905 if (!md->pages) 1906 goto out; 1907 1908 if (md->anon) 1909 seq_printf(m, " anon=%lu", md->anon); 1910 1911 if (md->dirty) 1912 seq_printf(m, " dirty=%lu", md->dirty); 1913 1914 if (md->pages != md->anon && md->pages != md->dirty) 1915 seq_printf(m, " mapped=%lu", md->pages); 1916 1917 if (md->mapcount_max > 1) 1918 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1919 1920 if (md->swapcache) 1921 seq_printf(m, " swapcache=%lu", md->swapcache); 1922 1923 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1924 seq_printf(m, " active=%lu", md->active); 1925 1926 if (md->writeback) 1927 seq_printf(m, " writeback=%lu", md->writeback); 1928 1929 for_each_node_state(nid, N_MEMORY) 1930 if (md->node[nid]) 1931 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1932 1933 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1934 out: 1935 seq_putc(m, '\n'); 1936 return 0; 1937 } 1938 1939 static const struct seq_operations proc_pid_numa_maps_op = { 1940 .start = m_start, 1941 .next = m_next, 1942 .stop = m_stop, 1943 .show = show_numa_map, 1944 }; 1945 1946 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1947 { 1948 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1949 sizeof(struct numa_maps_private)); 1950 } 1951 1952 const struct file_operations proc_pid_numa_maps_operations = { 1953 .open = pid_numa_maps_open, 1954 .read = seq_read, 1955 .llseek = seq_lseek, 1956 .release = proc_map_release, 1957 }; 1958 1959 #endif /* CONFIG_NUMA */ 1960