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