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 vma_stop(struct proc_maps_private *priv) 127 { 128 struct mm_struct *mm = priv->mm; 129 130 release_task_mempolicy(priv); 131 up_read(&mm->mmap_sem); 132 mmput(mm); 133 } 134 135 static struct vm_area_struct * 136 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma) 137 { 138 if (vma == priv->tail_vma) 139 return NULL; 140 return vma->vm_next ?: priv->tail_vma; 141 } 142 143 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma) 144 { 145 if (m->count < m->size) /* vma is copied successfully */ 146 m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL; 147 } 148 149 static void *m_start(struct seq_file *m, loff_t *ppos) 150 { 151 struct proc_maps_private *priv = m->private; 152 unsigned long last_addr = m->version; 153 struct mm_struct *mm; 154 struct vm_area_struct *vma; 155 unsigned int pos = *ppos; 156 157 /* See m_cache_vma(). Zero at the start or after lseek. */ 158 if (last_addr == -1UL) 159 return NULL; 160 161 priv->task = get_proc_task(priv->inode); 162 if (!priv->task) 163 return ERR_PTR(-ESRCH); 164 165 mm = priv->mm; 166 if (!mm || !mmget_not_zero(mm)) 167 return NULL; 168 169 if (down_read_killable(&mm->mmap_sem)) { 170 mmput(mm); 171 return ERR_PTR(-EINTR); 172 } 173 174 hold_task_mempolicy(priv); 175 priv->tail_vma = get_gate_vma(mm); 176 177 if (last_addr) { 178 vma = find_vma(mm, last_addr - 1); 179 if (vma && vma->vm_start <= last_addr) 180 vma = m_next_vma(priv, vma); 181 if (vma) 182 return vma; 183 } 184 185 m->version = 0; 186 if (pos < mm->map_count) { 187 for (vma = mm->mmap; pos; pos--) { 188 m->version = vma->vm_start; 189 vma = vma->vm_next; 190 } 191 return vma; 192 } 193 194 /* we do not bother to update m->version in this case */ 195 if (pos == mm->map_count && priv->tail_vma) 196 return priv->tail_vma; 197 198 vma_stop(priv); 199 return NULL; 200 } 201 202 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 203 { 204 struct proc_maps_private *priv = m->private; 205 struct vm_area_struct *next; 206 207 (*pos)++; 208 next = m_next_vma(priv, v); 209 if (!next) 210 vma_stop(priv); 211 return next; 212 } 213 214 static void m_stop(struct seq_file *m, void *v) 215 { 216 struct proc_maps_private *priv = m->private; 217 218 if (!IS_ERR_OR_NULL(v)) 219 vma_stop(priv); 220 if (priv->task) { 221 put_task_struct(priv->task); 222 priv->task = NULL; 223 } 224 } 225 226 static int proc_maps_open(struct inode *inode, struct file *file, 227 const struct seq_operations *ops, int psize) 228 { 229 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 230 231 if (!priv) 232 return -ENOMEM; 233 234 priv->inode = inode; 235 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 236 if (IS_ERR(priv->mm)) { 237 int err = PTR_ERR(priv->mm); 238 239 seq_release_private(inode, file); 240 return err; 241 } 242 243 return 0; 244 } 245 246 static int proc_map_release(struct inode *inode, struct file *file) 247 { 248 struct seq_file *seq = file->private_data; 249 struct proc_maps_private *priv = seq->private; 250 251 if (priv->mm) 252 mmdrop(priv->mm); 253 254 return seq_release_private(inode, file); 255 } 256 257 static int do_maps_open(struct inode *inode, struct file *file, 258 const struct seq_operations *ops) 259 { 260 return proc_maps_open(inode, file, ops, 261 sizeof(struct proc_maps_private)); 262 } 263 264 /* 265 * Indicate if the VMA is a stack for the given task; for 266 * /proc/PID/maps that is the stack of the main task. 267 */ 268 static int is_stack(struct vm_area_struct *vma) 269 { 270 /* 271 * We make no effort to guess what a given thread considers to be 272 * its "stack". It's not even well-defined for programs written 273 * languages like Go. 274 */ 275 return vma->vm_start <= vma->vm_mm->start_stack && 276 vma->vm_end >= vma->vm_mm->start_stack; 277 } 278 279 static void show_vma_header_prefix(struct seq_file *m, 280 unsigned long start, unsigned long end, 281 vm_flags_t flags, unsigned long long pgoff, 282 dev_t dev, unsigned long ino) 283 { 284 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 285 seq_put_hex_ll(m, NULL, start, 8); 286 seq_put_hex_ll(m, "-", end, 8); 287 seq_putc(m, ' '); 288 seq_putc(m, flags & VM_READ ? 'r' : '-'); 289 seq_putc(m, flags & VM_WRITE ? 'w' : '-'); 290 seq_putc(m, flags & VM_EXEC ? 'x' : '-'); 291 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p'); 292 seq_put_hex_ll(m, " ", pgoff, 8); 293 seq_put_hex_ll(m, " ", MAJOR(dev), 2); 294 seq_put_hex_ll(m, ":", MINOR(dev), 2); 295 seq_put_decimal_ull(m, " ", ino); 296 seq_putc(m, ' '); 297 } 298 299 static void 300 show_map_vma(struct seq_file *m, struct vm_area_struct *vma) 301 { 302 struct mm_struct *mm = vma->vm_mm; 303 struct file *file = vma->vm_file; 304 vm_flags_t flags = vma->vm_flags; 305 unsigned long ino = 0; 306 unsigned long long pgoff = 0; 307 unsigned long start, end; 308 dev_t dev = 0; 309 const char *name = NULL; 310 311 if (file) { 312 struct inode *inode = file_inode(vma->vm_file); 313 dev = inode->i_sb->s_dev; 314 ino = inode->i_ino; 315 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 316 } 317 318 start = vma->vm_start; 319 end = vma->vm_end; 320 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 321 322 /* 323 * Print the dentry name for named mappings, and a 324 * special [heap] marker for the heap: 325 */ 326 if (file) { 327 seq_pad(m, ' '); 328 seq_file_path(m, file, "\n"); 329 goto done; 330 } 331 332 if (vma->vm_ops && vma->vm_ops->name) { 333 name = vma->vm_ops->name(vma); 334 if (name) 335 goto done; 336 } 337 338 name = arch_vma_name(vma); 339 if (!name) { 340 if (!mm) { 341 name = "[vdso]"; 342 goto done; 343 } 344 345 if (vma->vm_start <= mm->brk && 346 vma->vm_end >= mm->start_brk) { 347 name = "[heap]"; 348 goto done; 349 } 350 351 if (is_stack(vma)) 352 name = "[stack]"; 353 } 354 355 done: 356 if (name) { 357 seq_pad(m, ' '); 358 seq_puts(m, name); 359 } 360 seq_putc(m, '\n'); 361 } 362 363 static int show_map(struct seq_file *m, void *v) 364 { 365 show_map_vma(m, v); 366 m_cache_vma(m, v); 367 return 0; 368 } 369 370 static const struct seq_operations proc_pid_maps_op = { 371 .start = m_start, 372 .next = m_next, 373 .stop = m_stop, 374 .show = show_map 375 }; 376 377 static int pid_maps_open(struct inode *inode, struct file *file) 378 { 379 return do_maps_open(inode, file, &proc_pid_maps_op); 380 } 381 382 const struct file_operations proc_pid_maps_operations = { 383 .open = pid_maps_open, 384 .read = seq_read, 385 .llseek = seq_lseek, 386 .release = proc_map_release, 387 }; 388 389 /* 390 * Proportional Set Size(PSS): my share of RSS. 391 * 392 * PSS of a process is the count of pages it has in memory, where each 393 * page is divided by the number of processes sharing it. So if a 394 * process has 1000 pages all to itself, and 1000 shared with one other 395 * process, its PSS will be 1500. 396 * 397 * To keep (accumulated) division errors low, we adopt a 64bit 398 * fixed-point pss counter to minimize division errors. So (pss >> 399 * PSS_SHIFT) would be the real byte count. 400 * 401 * A shift of 12 before division means (assuming 4K page size): 402 * - 1M 3-user-pages add up to 8KB errors; 403 * - supports mapcount up to 2^24, or 16M; 404 * - supports PSS up to 2^52 bytes, or 4PB. 405 */ 406 #define PSS_SHIFT 12 407 408 #ifdef CONFIG_PROC_PAGE_MONITOR 409 struct mem_size_stats { 410 unsigned long resident; 411 unsigned long shared_clean; 412 unsigned long shared_dirty; 413 unsigned long private_clean; 414 unsigned long private_dirty; 415 unsigned long referenced; 416 unsigned long anonymous; 417 unsigned long lazyfree; 418 unsigned long anonymous_thp; 419 unsigned long shmem_thp; 420 unsigned long file_thp; 421 unsigned long swap; 422 unsigned long shared_hugetlb; 423 unsigned long private_hugetlb; 424 u64 pss; 425 u64 pss_anon; 426 u64 pss_file; 427 u64 pss_shmem; 428 u64 pss_locked; 429 u64 swap_pss; 430 bool check_shmem_swap; 431 }; 432 433 static void smaps_page_accumulate(struct mem_size_stats *mss, 434 struct page *page, unsigned long size, unsigned long pss, 435 bool dirty, bool locked, bool private) 436 { 437 mss->pss += pss; 438 439 if (PageAnon(page)) 440 mss->pss_anon += pss; 441 else if (PageSwapBacked(page)) 442 mss->pss_shmem += pss; 443 else 444 mss->pss_file += pss; 445 446 if (locked) 447 mss->pss_locked += pss; 448 449 if (dirty || PageDirty(page)) { 450 if (private) 451 mss->private_dirty += size; 452 else 453 mss->shared_dirty += size; 454 } else { 455 if (private) 456 mss->private_clean += size; 457 else 458 mss->shared_clean += size; 459 } 460 } 461 462 static void smaps_account(struct mem_size_stats *mss, struct page *page, 463 bool compound, bool young, bool dirty, bool locked) 464 { 465 int i, nr = compound ? compound_nr(page) : 1; 466 unsigned long size = nr * PAGE_SIZE; 467 468 /* 469 * First accumulate quantities that depend only on |size| and the type 470 * of the compound page. 471 */ 472 if (PageAnon(page)) { 473 mss->anonymous += size; 474 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 475 mss->lazyfree += size; 476 } 477 478 mss->resident += size; 479 /* Accumulate the size in pages that have been accessed. */ 480 if (young || page_is_young(page) || PageReferenced(page)) 481 mss->referenced += size; 482 483 /* 484 * Then accumulate quantities that may depend on sharing, or that may 485 * differ page-by-page. 486 * 487 * page_count(page) == 1 guarantees the page is mapped exactly once. 488 * If any subpage of the compound page mapped with PTE it would elevate 489 * page_count(). 490 */ 491 if (page_count(page) == 1) { 492 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, 493 locked, true); 494 return; 495 } 496 for (i = 0; i < nr; i++, page++) { 497 int mapcount = page_mapcount(page); 498 unsigned long pss = PAGE_SIZE << PSS_SHIFT; 499 if (mapcount >= 2) 500 pss /= mapcount; 501 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked, 502 mapcount < 2); 503 } 504 } 505 506 #ifdef CONFIG_SHMEM 507 static int smaps_pte_hole(unsigned long addr, unsigned long end, 508 struct mm_walk *walk) 509 { 510 struct mem_size_stats *mss = walk->private; 511 512 mss->swap += shmem_partial_swap_usage( 513 walk->vma->vm_file->f_mapping, addr, end); 514 515 return 0; 516 } 517 #else 518 #define smaps_pte_hole NULL 519 #endif /* CONFIG_SHMEM */ 520 521 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 522 struct mm_walk *walk) 523 { 524 struct mem_size_stats *mss = walk->private; 525 struct vm_area_struct *vma = walk->vma; 526 bool locked = !!(vma->vm_flags & VM_LOCKED); 527 struct page *page = NULL; 528 529 if (pte_present(*pte)) { 530 page = vm_normal_page(vma, addr, *pte); 531 } else if (is_swap_pte(*pte)) { 532 swp_entry_t swpent = pte_to_swp_entry(*pte); 533 534 if (!non_swap_entry(swpent)) { 535 int mapcount; 536 537 mss->swap += PAGE_SIZE; 538 mapcount = swp_swapcount(swpent); 539 if (mapcount >= 2) { 540 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 541 542 do_div(pss_delta, mapcount); 543 mss->swap_pss += pss_delta; 544 } else { 545 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 546 } 547 } else if (is_migration_entry(swpent)) 548 page = migration_entry_to_page(swpent); 549 else if (is_device_private_entry(swpent)) 550 page = device_private_entry_to_page(swpent); 551 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 552 && pte_none(*pte))) { 553 page = find_get_entry(vma->vm_file->f_mapping, 554 linear_page_index(vma, addr)); 555 if (!page) 556 return; 557 558 if (xa_is_value(page)) 559 mss->swap += PAGE_SIZE; 560 else 561 put_page(page); 562 563 return; 564 } 565 566 if (!page) 567 return; 568 569 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked); 570 } 571 572 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 573 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 574 struct mm_walk *walk) 575 { 576 struct mem_size_stats *mss = walk->private; 577 struct vm_area_struct *vma = walk->vma; 578 bool locked = !!(vma->vm_flags & VM_LOCKED); 579 struct page *page; 580 581 /* FOLL_DUMP will return -EFAULT on huge zero page */ 582 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 583 if (IS_ERR_OR_NULL(page)) 584 return; 585 if (PageAnon(page)) 586 mss->anonymous_thp += HPAGE_PMD_SIZE; 587 else if (PageSwapBacked(page)) 588 mss->shmem_thp += HPAGE_PMD_SIZE; 589 else if (is_zone_device_page(page)) 590 /* pass */; 591 else 592 mss->file_thp += HPAGE_PMD_SIZE; 593 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked); 594 } 595 #else 596 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 597 struct mm_walk *walk) 598 { 599 } 600 #endif 601 602 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 603 struct mm_walk *walk) 604 { 605 struct vm_area_struct *vma = walk->vma; 606 pte_t *pte; 607 spinlock_t *ptl; 608 609 ptl = pmd_trans_huge_lock(pmd, vma); 610 if (ptl) { 611 if (pmd_present(*pmd)) 612 smaps_pmd_entry(pmd, addr, walk); 613 spin_unlock(ptl); 614 goto out; 615 } 616 617 if (pmd_trans_unstable(pmd)) 618 goto out; 619 /* 620 * The mmap_sem held all the way back in m_start() is what 621 * keeps khugepaged out of here and from collapsing things 622 * in here. 623 */ 624 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 625 for (; addr != end; pte++, addr += PAGE_SIZE) 626 smaps_pte_entry(pte, addr, walk); 627 pte_unmap_unlock(pte - 1, ptl); 628 out: 629 cond_resched(); 630 return 0; 631 } 632 633 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 634 { 635 /* 636 * Don't forget to update Documentation/ on changes. 637 */ 638 static const char mnemonics[BITS_PER_LONG][2] = { 639 /* 640 * In case if we meet a flag we don't know about. 641 */ 642 [0 ... (BITS_PER_LONG-1)] = "??", 643 644 [ilog2(VM_READ)] = "rd", 645 [ilog2(VM_WRITE)] = "wr", 646 [ilog2(VM_EXEC)] = "ex", 647 [ilog2(VM_SHARED)] = "sh", 648 [ilog2(VM_MAYREAD)] = "mr", 649 [ilog2(VM_MAYWRITE)] = "mw", 650 [ilog2(VM_MAYEXEC)] = "me", 651 [ilog2(VM_MAYSHARE)] = "ms", 652 [ilog2(VM_GROWSDOWN)] = "gd", 653 [ilog2(VM_PFNMAP)] = "pf", 654 [ilog2(VM_DENYWRITE)] = "dw", 655 #ifdef CONFIG_X86_INTEL_MPX 656 [ilog2(VM_MPX)] = "mp", 657 #endif 658 [ilog2(VM_LOCKED)] = "lo", 659 [ilog2(VM_IO)] = "io", 660 [ilog2(VM_SEQ_READ)] = "sr", 661 [ilog2(VM_RAND_READ)] = "rr", 662 [ilog2(VM_DONTCOPY)] = "dc", 663 [ilog2(VM_DONTEXPAND)] = "de", 664 [ilog2(VM_ACCOUNT)] = "ac", 665 [ilog2(VM_NORESERVE)] = "nr", 666 [ilog2(VM_HUGETLB)] = "ht", 667 [ilog2(VM_SYNC)] = "sf", 668 [ilog2(VM_ARCH_1)] = "ar", 669 [ilog2(VM_WIPEONFORK)] = "wf", 670 [ilog2(VM_DONTDUMP)] = "dd", 671 #ifdef CONFIG_MEM_SOFT_DIRTY 672 [ilog2(VM_SOFTDIRTY)] = "sd", 673 #endif 674 [ilog2(VM_MIXEDMAP)] = "mm", 675 [ilog2(VM_HUGEPAGE)] = "hg", 676 [ilog2(VM_NOHUGEPAGE)] = "nh", 677 [ilog2(VM_MERGEABLE)] = "mg", 678 [ilog2(VM_UFFD_MISSING)]= "um", 679 [ilog2(VM_UFFD_WP)] = "uw", 680 #ifdef CONFIG_ARCH_HAS_PKEYS 681 /* These come out via ProtectionKey: */ 682 [ilog2(VM_PKEY_BIT0)] = "", 683 [ilog2(VM_PKEY_BIT1)] = "", 684 [ilog2(VM_PKEY_BIT2)] = "", 685 [ilog2(VM_PKEY_BIT3)] = "", 686 #if VM_PKEY_BIT4 687 [ilog2(VM_PKEY_BIT4)] = "", 688 #endif 689 #endif /* CONFIG_ARCH_HAS_PKEYS */ 690 }; 691 size_t i; 692 693 seq_puts(m, "VmFlags: "); 694 for (i = 0; i < BITS_PER_LONG; i++) { 695 if (!mnemonics[i][0]) 696 continue; 697 if (vma->vm_flags & (1UL << i)) { 698 seq_putc(m, mnemonics[i][0]); 699 seq_putc(m, mnemonics[i][1]); 700 seq_putc(m, ' '); 701 } 702 } 703 seq_putc(m, '\n'); 704 } 705 706 #ifdef CONFIG_HUGETLB_PAGE 707 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 708 unsigned long addr, unsigned long end, 709 struct mm_walk *walk) 710 { 711 struct mem_size_stats *mss = walk->private; 712 struct vm_area_struct *vma = walk->vma; 713 struct page *page = NULL; 714 715 if (pte_present(*pte)) { 716 page = vm_normal_page(vma, addr, *pte); 717 } else if (is_swap_pte(*pte)) { 718 swp_entry_t swpent = pte_to_swp_entry(*pte); 719 720 if (is_migration_entry(swpent)) 721 page = migration_entry_to_page(swpent); 722 else if (is_device_private_entry(swpent)) 723 page = device_private_entry_to_page(swpent); 724 } 725 if (page) { 726 int mapcount = page_mapcount(page); 727 728 if (mapcount >= 2) 729 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 730 else 731 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 732 } 733 return 0; 734 } 735 #else 736 #define smaps_hugetlb_range NULL 737 #endif /* HUGETLB_PAGE */ 738 739 static const struct mm_walk_ops smaps_walk_ops = { 740 .pmd_entry = smaps_pte_range, 741 .hugetlb_entry = smaps_hugetlb_range, 742 }; 743 744 static const struct mm_walk_ops smaps_shmem_walk_ops = { 745 .pmd_entry = smaps_pte_range, 746 .hugetlb_entry = smaps_hugetlb_range, 747 .pte_hole = smaps_pte_hole, 748 }; 749 750 static void smap_gather_stats(struct vm_area_struct *vma, 751 struct mem_size_stats *mss) 752 { 753 #ifdef CONFIG_SHMEM 754 /* In case of smaps_rollup, reset the value from previous vma */ 755 mss->check_shmem_swap = false; 756 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 757 /* 758 * For shared or readonly shmem mappings we know that all 759 * swapped out pages belong to the shmem object, and we can 760 * obtain the swap value much more efficiently. For private 761 * writable mappings, we might have COW pages that are 762 * not affected by the parent swapped out pages of the shmem 763 * object, so we have to distinguish them during the page walk. 764 * Unless we know that the shmem object (or the part mapped by 765 * our VMA) has no swapped out pages at all. 766 */ 767 unsigned long shmem_swapped = shmem_swap_usage(vma); 768 769 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 770 !(vma->vm_flags & VM_WRITE)) { 771 mss->swap += shmem_swapped; 772 } else { 773 mss->check_shmem_swap = true; 774 walk_page_vma(vma, &smaps_shmem_walk_ops, mss); 775 return; 776 } 777 } 778 #endif 779 /* mmap_sem is held in m_start */ 780 walk_page_vma(vma, &smaps_walk_ops, mss); 781 } 782 783 #define SEQ_PUT_DEC(str, val) \ 784 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 785 786 /* Show the contents common for smaps and smaps_rollup */ 787 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, 788 bool rollup_mode) 789 { 790 SEQ_PUT_DEC("Rss: ", mss->resident); 791 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 792 if (rollup_mode) { 793 /* 794 * These are meaningful only for smaps_rollup, otherwise two of 795 * them are zero, and the other one is the same as Pss. 796 */ 797 SEQ_PUT_DEC(" kB\nPss_Anon: ", 798 mss->pss_anon >> PSS_SHIFT); 799 SEQ_PUT_DEC(" kB\nPss_File: ", 800 mss->pss_file >> PSS_SHIFT); 801 SEQ_PUT_DEC(" kB\nPss_Shmem: ", 802 mss->pss_shmem >> PSS_SHIFT); 803 } 804 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 805 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 806 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 807 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 808 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 809 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 810 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 811 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 812 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 813 SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp); 814 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 815 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 816 mss->private_hugetlb >> 10, 7); 817 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 818 SEQ_PUT_DEC(" kB\nSwapPss: ", 819 mss->swap_pss >> PSS_SHIFT); 820 SEQ_PUT_DEC(" kB\nLocked: ", 821 mss->pss_locked >> PSS_SHIFT); 822 seq_puts(m, " kB\n"); 823 } 824 825 static int show_smap(struct seq_file *m, void *v) 826 { 827 struct vm_area_struct *vma = v; 828 struct mem_size_stats mss; 829 830 memset(&mss, 0, sizeof(mss)); 831 832 smap_gather_stats(vma, &mss); 833 834 show_map_vma(m, vma); 835 836 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 837 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 838 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 839 seq_puts(m, " kB\n"); 840 841 __show_smap(m, &mss, false); 842 843 seq_printf(m, "THPeligible: %d\n", 844 transparent_hugepage_enabled(vma)); 845 846 if (arch_pkeys_enabled()) 847 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 848 show_smap_vma_flags(m, vma); 849 850 m_cache_vma(m, vma); 851 852 return 0; 853 } 854 855 static int show_smaps_rollup(struct seq_file *m, void *v) 856 { 857 struct proc_maps_private *priv = m->private; 858 struct mem_size_stats mss; 859 struct mm_struct *mm; 860 struct vm_area_struct *vma; 861 unsigned long last_vma_end = 0; 862 int ret = 0; 863 864 priv->task = get_proc_task(priv->inode); 865 if (!priv->task) 866 return -ESRCH; 867 868 mm = priv->mm; 869 if (!mm || !mmget_not_zero(mm)) { 870 ret = -ESRCH; 871 goto out_put_task; 872 } 873 874 memset(&mss, 0, sizeof(mss)); 875 876 ret = down_read_killable(&mm->mmap_sem); 877 if (ret) 878 goto out_put_mm; 879 880 hold_task_mempolicy(priv); 881 882 for (vma = priv->mm->mmap; vma; vma = vma->vm_next) { 883 smap_gather_stats(vma, &mss); 884 last_vma_end = vma->vm_end; 885 } 886 887 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 888 last_vma_end, 0, 0, 0, 0); 889 seq_pad(m, ' '); 890 seq_puts(m, "[rollup]\n"); 891 892 __show_smap(m, &mss, true); 893 894 release_task_mempolicy(priv); 895 up_read(&mm->mmap_sem); 896 897 out_put_mm: 898 mmput(mm); 899 out_put_task: 900 put_task_struct(priv->task); 901 priv->task = NULL; 902 903 return ret; 904 } 905 #undef SEQ_PUT_DEC 906 907 static const struct seq_operations proc_pid_smaps_op = { 908 .start = m_start, 909 .next = m_next, 910 .stop = m_stop, 911 .show = show_smap 912 }; 913 914 static int pid_smaps_open(struct inode *inode, struct file *file) 915 { 916 return do_maps_open(inode, file, &proc_pid_smaps_op); 917 } 918 919 static int smaps_rollup_open(struct inode *inode, struct file *file) 920 { 921 int ret; 922 struct proc_maps_private *priv; 923 924 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 925 if (!priv) 926 return -ENOMEM; 927 928 ret = single_open(file, show_smaps_rollup, priv); 929 if (ret) 930 goto out_free; 931 932 priv->inode = inode; 933 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 934 if (IS_ERR(priv->mm)) { 935 ret = PTR_ERR(priv->mm); 936 937 single_release(inode, file); 938 goto out_free; 939 } 940 941 return 0; 942 943 out_free: 944 kfree(priv); 945 return ret; 946 } 947 948 static int smaps_rollup_release(struct inode *inode, struct file *file) 949 { 950 struct seq_file *seq = file->private_data; 951 struct proc_maps_private *priv = seq->private; 952 953 if (priv->mm) 954 mmdrop(priv->mm); 955 956 kfree(priv); 957 return single_release(inode, file); 958 } 959 960 const struct file_operations proc_pid_smaps_operations = { 961 .open = pid_smaps_open, 962 .read = seq_read, 963 .llseek = seq_lseek, 964 .release = proc_map_release, 965 }; 966 967 const struct file_operations proc_pid_smaps_rollup_operations = { 968 .open = smaps_rollup_open, 969 .read = seq_read, 970 .llseek = seq_lseek, 971 .release = smaps_rollup_release, 972 }; 973 974 enum clear_refs_types { 975 CLEAR_REFS_ALL = 1, 976 CLEAR_REFS_ANON, 977 CLEAR_REFS_MAPPED, 978 CLEAR_REFS_SOFT_DIRTY, 979 CLEAR_REFS_MM_HIWATER_RSS, 980 CLEAR_REFS_LAST, 981 }; 982 983 struct clear_refs_private { 984 enum clear_refs_types type; 985 }; 986 987 #ifdef CONFIG_MEM_SOFT_DIRTY 988 static inline void clear_soft_dirty(struct vm_area_struct *vma, 989 unsigned long addr, pte_t *pte) 990 { 991 /* 992 * The soft-dirty tracker uses #PF-s to catch writes 993 * to pages, so write-protect the pte as well. See the 994 * Documentation/admin-guide/mm/soft-dirty.rst for full description 995 * of how soft-dirty works. 996 */ 997 pte_t ptent = *pte; 998 999 if (pte_present(ptent)) { 1000 pte_t old_pte; 1001 1002 old_pte = ptep_modify_prot_start(vma, addr, pte); 1003 ptent = pte_wrprotect(old_pte); 1004 ptent = pte_clear_soft_dirty(ptent); 1005 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); 1006 } else if (is_swap_pte(ptent)) { 1007 ptent = pte_swp_clear_soft_dirty(ptent); 1008 set_pte_at(vma->vm_mm, addr, pte, ptent); 1009 } 1010 } 1011 #else 1012 static inline void clear_soft_dirty(struct vm_area_struct *vma, 1013 unsigned long addr, pte_t *pte) 1014 { 1015 } 1016 #endif 1017 1018 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 1019 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1020 unsigned long addr, pmd_t *pmdp) 1021 { 1022 pmd_t old, pmd = *pmdp; 1023 1024 if (pmd_present(pmd)) { 1025 /* See comment in change_huge_pmd() */ 1026 old = pmdp_invalidate(vma, addr, pmdp); 1027 if (pmd_dirty(old)) 1028 pmd = pmd_mkdirty(pmd); 1029 if (pmd_young(old)) 1030 pmd = pmd_mkyoung(pmd); 1031 1032 pmd = pmd_wrprotect(pmd); 1033 pmd = pmd_clear_soft_dirty(pmd); 1034 1035 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1036 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 1037 pmd = pmd_swp_clear_soft_dirty(pmd); 1038 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 1039 } 1040 } 1041 #else 1042 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 1043 unsigned long addr, pmd_t *pmdp) 1044 { 1045 } 1046 #endif 1047 1048 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 1049 unsigned long end, struct mm_walk *walk) 1050 { 1051 struct clear_refs_private *cp = walk->private; 1052 struct vm_area_struct *vma = walk->vma; 1053 pte_t *pte, ptent; 1054 spinlock_t *ptl; 1055 struct page *page; 1056 1057 ptl = pmd_trans_huge_lock(pmd, vma); 1058 if (ptl) { 1059 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1060 clear_soft_dirty_pmd(vma, addr, pmd); 1061 goto out; 1062 } 1063 1064 if (!pmd_present(*pmd)) 1065 goto out; 1066 1067 page = pmd_page(*pmd); 1068 1069 /* Clear accessed and referenced bits. */ 1070 pmdp_test_and_clear_young(vma, addr, pmd); 1071 test_and_clear_page_young(page); 1072 ClearPageReferenced(page); 1073 out: 1074 spin_unlock(ptl); 1075 return 0; 1076 } 1077 1078 if (pmd_trans_unstable(pmd)) 1079 return 0; 1080 1081 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1082 for (; addr != end; pte++, addr += PAGE_SIZE) { 1083 ptent = *pte; 1084 1085 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1086 clear_soft_dirty(vma, addr, pte); 1087 continue; 1088 } 1089 1090 if (!pte_present(ptent)) 1091 continue; 1092 1093 page = vm_normal_page(vma, addr, ptent); 1094 if (!page) 1095 continue; 1096 1097 /* Clear accessed and referenced bits. */ 1098 ptep_test_and_clear_young(vma, addr, pte); 1099 test_and_clear_page_young(page); 1100 ClearPageReferenced(page); 1101 } 1102 pte_unmap_unlock(pte - 1, ptl); 1103 cond_resched(); 1104 return 0; 1105 } 1106 1107 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1108 struct mm_walk *walk) 1109 { 1110 struct clear_refs_private *cp = walk->private; 1111 struct vm_area_struct *vma = walk->vma; 1112 1113 if (vma->vm_flags & VM_PFNMAP) 1114 return 1; 1115 1116 /* 1117 * Writing 1 to /proc/pid/clear_refs affects all pages. 1118 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1119 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1120 * Writing 4 to /proc/pid/clear_refs affects all pages. 1121 */ 1122 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1123 return 1; 1124 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1125 return 1; 1126 return 0; 1127 } 1128 1129 static const struct mm_walk_ops clear_refs_walk_ops = { 1130 .pmd_entry = clear_refs_pte_range, 1131 .test_walk = clear_refs_test_walk, 1132 }; 1133 1134 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1135 size_t count, loff_t *ppos) 1136 { 1137 struct task_struct *task; 1138 char buffer[PROC_NUMBUF]; 1139 struct mm_struct *mm; 1140 struct vm_area_struct *vma; 1141 enum clear_refs_types type; 1142 struct mmu_gather tlb; 1143 int itype; 1144 int rv; 1145 1146 memset(buffer, 0, sizeof(buffer)); 1147 if (count > sizeof(buffer) - 1) 1148 count = sizeof(buffer) - 1; 1149 if (copy_from_user(buffer, buf, count)) 1150 return -EFAULT; 1151 rv = kstrtoint(strstrip(buffer), 10, &itype); 1152 if (rv < 0) 1153 return rv; 1154 type = (enum clear_refs_types)itype; 1155 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1156 return -EINVAL; 1157 1158 task = get_proc_task(file_inode(file)); 1159 if (!task) 1160 return -ESRCH; 1161 mm = get_task_mm(task); 1162 if (mm) { 1163 struct mmu_notifier_range range; 1164 struct clear_refs_private cp = { 1165 .type = type, 1166 }; 1167 1168 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1169 if (down_write_killable(&mm->mmap_sem)) { 1170 count = -EINTR; 1171 goto out_mm; 1172 } 1173 1174 /* 1175 * Writing 5 to /proc/pid/clear_refs resets the peak 1176 * resident set size to this mm's current rss value. 1177 */ 1178 reset_mm_hiwater_rss(mm); 1179 up_write(&mm->mmap_sem); 1180 goto out_mm; 1181 } 1182 1183 if (down_read_killable(&mm->mmap_sem)) { 1184 count = -EINTR; 1185 goto out_mm; 1186 } 1187 tlb_gather_mmu(&tlb, mm, 0, -1); 1188 if (type == CLEAR_REFS_SOFT_DIRTY) { 1189 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1190 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1191 continue; 1192 up_read(&mm->mmap_sem); 1193 if (down_write_killable(&mm->mmap_sem)) { 1194 count = -EINTR; 1195 goto out_mm; 1196 } 1197 /* 1198 * Avoid to modify vma->vm_flags 1199 * without locked ops while the 1200 * coredump reads the vm_flags. 1201 */ 1202 if (!mmget_still_valid(mm)) { 1203 /* 1204 * Silently return "count" 1205 * like if get_task_mm() 1206 * failed. FIXME: should this 1207 * function have returned 1208 * -ESRCH if get_task_mm() 1209 * failed like if 1210 * get_proc_task() fails? 1211 */ 1212 up_write(&mm->mmap_sem); 1213 goto out_mm; 1214 } 1215 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1216 vma->vm_flags &= ~VM_SOFTDIRTY; 1217 vma_set_page_prot(vma); 1218 } 1219 downgrade_write(&mm->mmap_sem); 1220 break; 1221 } 1222 1223 mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY, 1224 0, NULL, mm, 0, -1UL); 1225 mmu_notifier_invalidate_range_start(&range); 1226 } 1227 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops, 1228 &cp); 1229 if (type == CLEAR_REFS_SOFT_DIRTY) 1230 mmu_notifier_invalidate_range_end(&range); 1231 tlb_finish_mmu(&tlb, 0, -1); 1232 up_read(&mm->mmap_sem); 1233 out_mm: 1234 mmput(mm); 1235 } 1236 put_task_struct(task); 1237 1238 return count; 1239 } 1240 1241 const struct file_operations proc_clear_refs_operations = { 1242 .write = clear_refs_write, 1243 .llseek = noop_llseek, 1244 }; 1245 1246 typedef struct { 1247 u64 pme; 1248 } pagemap_entry_t; 1249 1250 struct pagemapread { 1251 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1252 pagemap_entry_t *buffer; 1253 bool show_pfn; 1254 }; 1255 1256 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1257 #define PAGEMAP_WALK_MASK (PMD_MASK) 1258 1259 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1260 #define PM_PFRAME_BITS 55 1261 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1262 #define PM_SOFT_DIRTY BIT_ULL(55) 1263 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1264 #define PM_FILE BIT_ULL(61) 1265 #define PM_SWAP BIT_ULL(62) 1266 #define PM_PRESENT BIT_ULL(63) 1267 1268 #define PM_END_OF_BUFFER 1 1269 1270 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1271 { 1272 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1273 } 1274 1275 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1276 struct pagemapread *pm) 1277 { 1278 pm->buffer[pm->pos++] = *pme; 1279 if (pm->pos >= pm->len) 1280 return PM_END_OF_BUFFER; 1281 return 0; 1282 } 1283 1284 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1285 struct mm_walk *walk) 1286 { 1287 struct pagemapread *pm = walk->private; 1288 unsigned long addr = start; 1289 int err = 0; 1290 1291 while (addr < end) { 1292 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1293 pagemap_entry_t pme = make_pme(0, 0); 1294 /* End of address space hole, which we mark as non-present. */ 1295 unsigned long hole_end; 1296 1297 if (vma) 1298 hole_end = min(end, vma->vm_start); 1299 else 1300 hole_end = end; 1301 1302 for (; addr < hole_end; addr += PAGE_SIZE) { 1303 err = add_to_pagemap(addr, &pme, pm); 1304 if (err) 1305 goto out; 1306 } 1307 1308 if (!vma) 1309 break; 1310 1311 /* Addresses in the VMA. */ 1312 if (vma->vm_flags & VM_SOFTDIRTY) 1313 pme = make_pme(0, PM_SOFT_DIRTY); 1314 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1315 err = add_to_pagemap(addr, &pme, pm); 1316 if (err) 1317 goto out; 1318 } 1319 } 1320 out: 1321 return err; 1322 } 1323 1324 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1325 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1326 { 1327 u64 frame = 0, flags = 0; 1328 struct page *page = NULL; 1329 1330 if (pte_present(pte)) { 1331 if (pm->show_pfn) 1332 frame = pte_pfn(pte); 1333 flags |= PM_PRESENT; 1334 page = vm_normal_page(vma, addr, pte); 1335 if (pte_soft_dirty(pte)) 1336 flags |= PM_SOFT_DIRTY; 1337 } else if (is_swap_pte(pte)) { 1338 swp_entry_t entry; 1339 if (pte_swp_soft_dirty(pte)) 1340 flags |= PM_SOFT_DIRTY; 1341 entry = pte_to_swp_entry(pte); 1342 if (pm->show_pfn) 1343 frame = swp_type(entry) | 1344 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1345 flags |= PM_SWAP; 1346 if (is_migration_entry(entry)) 1347 page = migration_entry_to_page(entry); 1348 1349 if (is_device_private_entry(entry)) 1350 page = device_private_entry_to_page(entry); 1351 } 1352 1353 if (page && !PageAnon(page)) 1354 flags |= PM_FILE; 1355 if (page && page_mapcount(page) == 1) 1356 flags |= PM_MMAP_EXCLUSIVE; 1357 if (vma->vm_flags & VM_SOFTDIRTY) 1358 flags |= PM_SOFT_DIRTY; 1359 1360 return make_pme(frame, flags); 1361 } 1362 1363 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1364 struct mm_walk *walk) 1365 { 1366 struct vm_area_struct *vma = walk->vma; 1367 struct pagemapread *pm = walk->private; 1368 spinlock_t *ptl; 1369 pte_t *pte, *orig_pte; 1370 int err = 0; 1371 1372 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1373 ptl = pmd_trans_huge_lock(pmdp, vma); 1374 if (ptl) { 1375 u64 flags = 0, frame = 0; 1376 pmd_t pmd = *pmdp; 1377 struct page *page = NULL; 1378 1379 if (vma->vm_flags & VM_SOFTDIRTY) 1380 flags |= PM_SOFT_DIRTY; 1381 1382 if (pmd_present(pmd)) { 1383 page = pmd_page(pmd); 1384 1385 flags |= PM_PRESENT; 1386 if (pmd_soft_dirty(pmd)) 1387 flags |= PM_SOFT_DIRTY; 1388 if (pm->show_pfn) 1389 frame = pmd_pfn(pmd) + 1390 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1391 } 1392 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1393 else if (is_swap_pmd(pmd)) { 1394 swp_entry_t entry = pmd_to_swp_entry(pmd); 1395 unsigned long offset; 1396 1397 if (pm->show_pfn) { 1398 offset = swp_offset(entry) + 1399 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1400 frame = swp_type(entry) | 1401 (offset << MAX_SWAPFILES_SHIFT); 1402 } 1403 flags |= PM_SWAP; 1404 if (pmd_swp_soft_dirty(pmd)) 1405 flags |= PM_SOFT_DIRTY; 1406 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1407 page = migration_entry_to_page(entry); 1408 } 1409 #endif 1410 1411 if (page && page_mapcount(page) == 1) 1412 flags |= PM_MMAP_EXCLUSIVE; 1413 1414 for (; addr != end; addr += PAGE_SIZE) { 1415 pagemap_entry_t pme = make_pme(frame, flags); 1416 1417 err = add_to_pagemap(addr, &pme, pm); 1418 if (err) 1419 break; 1420 if (pm->show_pfn) { 1421 if (flags & PM_PRESENT) 1422 frame++; 1423 else if (flags & PM_SWAP) 1424 frame += (1 << MAX_SWAPFILES_SHIFT); 1425 } 1426 } 1427 spin_unlock(ptl); 1428 return err; 1429 } 1430 1431 if (pmd_trans_unstable(pmdp)) 1432 return 0; 1433 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1434 1435 /* 1436 * We can assume that @vma always points to a valid one and @end never 1437 * goes beyond vma->vm_end. 1438 */ 1439 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1440 for (; addr < end; pte++, addr += PAGE_SIZE) { 1441 pagemap_entry_t pme; 1442 1443 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1444 err = add_to_pagemap(addr, &pme, pm); 1445 if (err) 1446 break; 1447 } 1448 pte_unmap_unlock(orig_pte, ptl); 1449 1450 cond_resched(); 1451 1452 return err; 1453 } 1454 1455 #ifdef CONFIG_HUGETLB_PAGE 1456 /* This function walks within one hugetlb entry in the single call */ 1457 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1458 unsigned long addr, unsigned long end, 1459 struct mm_walk *walk) 1460 { 1461 struct pagemapread *pm = walk->private; 1462 struct vm_area_struct *vma = walk->vma; 1463 u64 flags = 0, frame = 0; 1464 int err = 0; 1465 pte_t pte; 1466 1467 if (vma->vm_flags & VM_SOFTDIRTY) 1468 flags |= PM_SOFT_DIRTY; 1469 1470 pte = huge_ptep_get(ptep); 1471 if (pte_present(pte)) { 1472 struct page *page = pte_page(pte); 1473 1474 if (!PageAnon(page)) 1475 flags |= PM_FILE; 1476 1477 if (page_mapcount(page) == 1) 1478 flags |= PM_MMAP_EXCLUSIVE; 1479 1480 flags |= PM_PRESENT; 1481 if (pm->show_pfn) 1482 frame = pte_pfn(pte) + 1483 ((addr & ~hmask) >> PAGE_SHIFT); 1484 } 1485 1486 for (; addr != end; addr += PAGE_SIZE) { 1487 pagemap_entry_t pme = make_pme(frame, flags); 1488 1489 err = add_to_pagemap(addr, &pme, pm); 1490 if (err) 1491 return err; 1492 if (pm->show_pfn && (flags & PM_PRESENT)) 1493 frame++; 1494 } 1495 1496 cond_resched(); 1497 1498 return err; 1499 } 1500 #else 1501 #define pagemap_hugetlb_range NULL 1502 #endif /* HUGETLB_PAGE */ 1503 1504 static const struct mm_walk_ops pagemap_ops = { 1505 .pmd_entry = pagemap_pmd_range, 1506 .pte_hole = pagemap_pte_hole, 1507 .hugetlb_entry = pagemap_hugetlb_range, 1508 }; 1509 1510 /* 1511 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1512 * 1513 * For each page in the address space, this file contains one 64-bit entry 1514 * consisting of the following: 1515 * 1516 * Bits 0-54 page frame number (PFN) if present 1517 * Bits 0-4 swap type if swapped 1518 * Bits 5-54 swap offset if swapped 1519 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1520 * Bit 56 page exclusively mapped 1521 * Bits 57-60 zero 1522 * Bit 61 page is file-page or shared-anon 1523 * Bit 62 page swapped 1524 * Bit 63 page present 1525 * 1526 * If the page is not present but in swap, then the PFN contains an 1527 * encoding of the swap file number and the page's offset into the 1528 * swap. Unmapped pages return a null PFN. This allows determining 1529 * precisely which pages are mapped (or in swap) and comparing mapped 1530 * pages between processes. 1531 * 1532 * Efficient users of this interface will use /proc/pid/maps to 1533 * determine which areas of memory are actually mapped and llseek to 1534 * skip over unmapped regions. 1535 */ 1536 static ssize_t pagemap_read(struct file *file, char __user *buf, 1537 size_t count, loff_t *ppos) 1538 { 1539 struct mm_struct *mm = file->private_data; 1540 struct pagemapread pm; 1541 unsigned long src; 1542 unsigned long svpfn; 1543 unsigned long start_vaddr; 1544 unsigned long end_vaddr; 1545 int ret = 0, copied = 0; 1546 1547 if (!mm || !mmget_not_zero(mm)) 1548 goto out; 1549 1550 ret = -EINVAL; 1551 /* file position must be aligned */ 1552 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1553 goto out_mm; 1554 1555 ret = 0; 1556 if (!count) 1557 goto out_mm; 1558 1559 /* do not disclose physical addresses: attack vector */ 1560 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1561 1562 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1563 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1564 ret = -ENOMEM; 1565 if (!pm.buffer) 1566 goto out_mm; 1567 1568 src = *ppos; 1569 svpfn = src / PM_ENTRY_BYTES; 1570 start_vaddr = svpfn << PAGE_SHIFT; 1571 end_vaddr = mm->task_size; 1572 1573 /* watch out for wraparound */ 1574 if (svpfn > mm->task_size >> PAGE_SHIFT) 1575 start_vaddr = end_vaddr; 1576 1577 /* 1578 * The odds are that this will stop walking way 1579 * before end_vaddr, because the length of the 1580 * user buffer is tracked in "pm", and the walk 1581 * will stop when we hit the end of the buffer. 1582 */ 1583 ret = 0; 1584 while (count && (start_vaddr < end_vaddr)) { 1585 int len; 1586 unsigned long end; 1587 1588 pm.pos = 0; 1589 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1590 /* overflow ? */ 1591 if (end < start_vaddr || end > end_vaddr) 1592 end = end_vaddr; 1593 ret = down_read_killable(&mm->mmap_sem); 1594 if (ret) 1595 goto out_free; 1596 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm); 1597 up_read(&mm->mmap_sem); 1598 start_vaddr = end; 1599 1600 len = min(count, PM_ENTRY_BYTES * pm.pos); 1601 if (copy_to_user(buf, pm.buffer, len)) { 1602 ret = -EFAULT; 1603 goto out_free; 1604 } 1605 copied += len; 1606 buf += len; 1607 count -= len; 1608 } 1609 *ppos += copied; 1610 if (!ret || ret == PM_END_OF_BUFFER) 1611 ret = copied; 1612 1613 out_free: 1614 kfree(pm.buffer); 1615 out_mm: 1616 mmput(mm); 1617 out: 1618 return ret; 1619 } 1620 1621 static int pagemap_open(struct inode *inode, struct file *file) 1622 { 1623 struct mm_struct *mm; 1624 1625 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1626 if (IS_ERR(mm)) 1627 return PTR_ERR(mm); 1628 file->private_data = mm; 1629 return 0; 1630 } 1631 1632 static int pagemap_release(struct inode *inode, struct file *file) 1633 { 1634 struct mm_struct *mm = file->private_data; 1635 1636 if (mm) 1637 mmdrop(mm); 1638 return 0; 1639 } 1640 1641 const struct file_operations proc_pagemap_operations = { 1642 .llseek = mem_lseek, /* borrow this */ 1643 .read = pagemap_read, 1644 .open = pagemap_open, 1645 .release = pagemap_release, 1646 }; 1647 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1648 1649 #ifdef CONFIG_NUMA 1650 1651 struct numa_maps { 1652 unsigned long pages; 1653 unsigned long anon; 1654 unsigned long active; 1655 unsigned long writeback; 1656 unsigned long mapcount_max; 1657 unsigned long dirty; 1658 unsigned long swapcache; 1659 unsigned long node[MAX_NUMNODES]; 1660 }; 1661 1662 struct numa_maps_private { 1663 struct proc_maps_private proc_maps; 1664 struct numa_maps md; 1665 }; 1666 1667 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1668 unsigned long nr_pages) 1669 { 1670 int count = page_mapcount(page); 1671 1672 md->pages += nr_pages; 1673 if (pte_dirty || PageDirty(page)) 1674 md->dirty += nr_pages; 1675 1676 if (PageSwapCache(page)) 1677 md->swapcache += nr_pages; 1678 1679 if (PageActive(page) || PageUnevictable(page)) 1680 md->active += nr_pages; 1681 1682 if (PageWriteback(page)) 1683 md->writeback += nr_pages; 1684 1685 if (PageAnon(page)) 1686 md->anon += nr_pages; 1687 1688 if (count > md->mapcount_max) 1689 md->mapcount_max = count; 1690 1691 md->node[page_to_nid(page)] += nr_pages; 1692 } 1693 1694 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1695 unsigned long addr) 1696 { 1697 struct page *page; 1698 int nid; 1699 1700 if (!pte_present(pte)) 1701 return NULL; 1702 1703 page = vm_normal_page(vma, addr, pte); 1704 if (!page) 1705 return NULL; 1706 1707 if (PageReserved(page)) 1708 return NULL; 1709 1710 nid = page_to_nid(page); 1711 if (!node_isset(nid, node_states[N_MEMORY])) 1712 return NULL; 1713 1714 return page; 1715 } 1716 1717 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1718 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1719 struct vm_area_struct *vma, 1720 unsigned long addr) 1721 { 1722 struct page *page; 1723 int nid; 1724 1725 if (!pmd_present(pmd)) 1726 return NULL; 1727 1728 page = vm_normal_page_pmd(vma, addr, pmd); 1729 if (!page) 1730 return NULL; 1731 1732 if (PageReserved(page)) 1733 return NULL; 1734 1735 nid = page_to_nid(page); 1736 if (!node_isset(nid, node_states[N_MEMORY])) 1737 return NULL; 1738 1739 return page; 1740 } 1741 #endif 1742 1743 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1744 unsigned long end, struct mm_walk *walk) 1745 { 1746 struct numa_maps *md = walk->private; 1747 struct vm_area_struct *vma = walk->vma; 1748 spinlock_t *ptl; 1749 pte_t *orig_pte; 1750 pte_t *pte; 1751 1752 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1753 ptl = pmd_trans_huge_lock(pmd, vma); 1754 if (ptl) { 1755 struct page *page; 1756 1757 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1758 if (page) 1759 gather_stats(page, md, pmd_dirty(*pmd), 1760 HPAGE_PMD_SIZE/PAGE_SIZE); 1761 spin_unlock(ptl); 1762 return 0; 1763 } 1764 1765 if (pmd_trans_unstable(pmd)) 1766 return 0; 1767 #endif 1768 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1769 do { 1770 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1771 if (!page) 1772 continue; 1773 gather_stats(page, md, pte_dirty(*pte), 1); 1774 1775 } while (pte++, addr += PAGE_SIZE, addr != end); 1776 pte_unmap_unlock(orig_pte, ptl); 1777 cond_resched(); 1778 return 0; 1779 } 1780 #ifdef CONFIG_HUGETLB_PAGE 1781 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1782 unsigned long addr, unsigned long end, struct mm_walk *walk) 1783 { 1784 pte_t huge_pte = huge_ptep_get(pte); 1785 struct numa_maps *md; 1786 struct page *page; 1787 1788 if (!pte_present(huge_pte)) 1789 return 0; 1790 1791 page = pte_page(huge_pte); 1792 if (!page) 1793 return 0; 1794 1795 md = walk->private; 1796 gather_stats(page, md, pte_dirty(huge_pte), 1); 1797 return 0; 1798 } 1799 1800 #else 1801 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1802 unsigned long addr, unsigned long end, struct mm_walk *walk) 1803 { 1804 return 0; 1805 } 1806 #endif 1807 1808 static const struct mm_walk_ops show_numa_ops = { 1809 .hugetlb_entry = gather_hugetlb_stats, 1810 .pmd_entry = gather_pte_stats, 1811 }; 1812 1813 /* 1814 * Display pages allocated per node and memory policy via /proc. 1815 */ 1816 static int show_numa_map(struct seq_file *m, void *v) 1817 { 1818 struct numa_maps_private *numa_priv = m->private; 1819 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1820 struct vm_area_struct *vma = v; 1821 struct numa_maps *md = &numa_priv->md; 1822 struct file *file = vma->vm_file; 1823 struct mm_struct *mm = vma->vm_mm; 1824 struct mempolicy *pol; 1825 char buffer[64]; 1826 int nid; 1827 1828 if (!mm) 1829 return 0; 1830 1831 /* Ensure we start with an empty set of numa_maps statistics. */ 1832 memset(md, 0, sizeof(*md)); 1833 1834 pol = __get_vma_policy(vma, vma->vm_start); 1835 if (pol) { 1836 mpol_to_str(buffer, sizeof(buffer), pol); 1837 mpol_cond_put(pol); 1838 } else { 1839 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1840 } 1841 1842 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1843 1844 if (file) { 1845 seq_puts(m, " file="); 1846 seq_file_path(m, file, "\n\t= "); 1847 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1848 seq_puts(m, " heap"); 1849 } else if (is_stack(vma)) { 1850 seq_puts(m, " stack"); 1851 } 1852 1853 if (is_vm_hugetlb_page(vma)) 1854 seq_puts(m, " huge"); 1855 1856 /* mmap_sem is held by m_start */ 1857 walk_page_vma(vma, &show_numa_ops, md); 1858 1859 if (!md->pages) 1860 goto out; 1861 1862 if (md->anon) 1863 seq_printf(m, " anon=%lu", md->anon); 1864 1865 if (md->dirty) 1866 seq_printf(m, " dirty=%lu", md->dirty); 1867 1868 if (md->pages != md->anon && md->pages != md->dirty) 1869 seq_printf(m, " mapped=%lu", md->pages); 1870 1871 if (md->mapcount_max > 1) 1872 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1873 1874 if (md->swapcache) 1875 seq_printf(m, " swapcache=%lu", md->swapcache); 1876 1877 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1878 seq_printf(m, " active=%lu", md->active); 1879 1880 if (md->writeback) 1881 seq_printf(m, " writeback=%lu", md->writeback); 1882 1883 for_each_node_state(nid, N_MEMORY) 1884 if (md->node[nid]) 1885 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1886 1887 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1888 out: 1889 seq_putc(m, '\n'); 1890 m_cache_vma(m, vma); 1891 return 0; 1892 } 1893 1894 static const struct seq_operations proc_pid_numa_maps_op = { 1895 .start = m_start, 1896 .next = m_next, 1897 .stop = m_stop, 1898 .show = show_numa_map, 1899 }; 1900 1901 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1902 { 1903 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1904 sizeof(struct numa_maps_private)); 1905 } 1906 1907 const struct file_operations proc_pid_numa_maps_operations = { 1908 .open = pid_numa_maps_open, 1909 .read = seq_read, 1910 .llseek = seq_lseek, 1911 .release = proc_map_release, 1912 }; 1913 1914 #endif /* CONFIG_NUMA */ 1915