1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/mm.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", 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 down_read(&mm->mmap_sem); 170 hold_task_mempolicy(priv); 171 priv->tail_vma = get_gate_vma(mm); 172 173 if (last_addr) { 174 vma = find_vma(mm, last_addr - 1); 175 if (vma && vma->vm_start <= last_addr) 176 vma = m_next_vma(priv, vma); 177 if (vma) 178 return vma; 179 } 180 181 m->version = 0; 182 if (pos < mm->map_count) { 183 for (vma = mm->mmap; pos; pos--) { 184 m->version = vma->vm_start; 185 vma = vma->vm_next; 186 } 187 return vma; 188 } 189 190 /* we do not bother to update m->version in this case */ 191 if (pos == mm->map_count && priv->tail_vma) 192 return priv->tail_vma; 193 194 vma_stop(priv); 195 return NULL; 196 } 197 198 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 199 { 200 struct proc_maps_private *priv = m->private; 201 struct vm_area_struct *next; 202 203 (*pos)++; 204 next = m_next_vma(priv, v); 205 if (!next) 206 vma_stop(priv); 207 return next; 208 } 209 210 static void m_stop(struct seq_file *m, void *v) 211 { 212 struct proc_maps_private *priv = m->private; 213 214 if (!IS_ERR_OR_NULL(v)) 215 vma_stop(priv); 216 if (priv->task) { 217 put_task_struct(priv->task); 218 priv->task = NULL; 219 } 220 } 221 222 static int proc_maps_open(struct inode *inode, struct file *file, 223 const struct seq_operations *ops, int psize) 224 { 225 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 226 227 if (!priv) 228 return -ENOMEM; 229 230 priv->inode = inode; 231 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 232 if (IS_ERR(priv->mm)) { 233 int err = PTR_ERR(priv->mm); 234 235 seq_release_private(inode, file); 236 return err; 237 } 238 239 return 0; 240 } 241 242 static int proc_map_release(struct inode *inode, struct file *file) 243 { 244 struct seq_file *seq = file->private_data; 245 struct proc_maps_private *priv = seq->private; 246 247 if (priv->mm) 248 mmdrop(priv->mm); 249 250 return seq_release_private(inode, file); 251 } 252 253 static int do_maps_open(struct inode *inode, struct file *file, 254 const struct seq_operations *ops) 255 { 256 return proc_maps_open(inode, file, ops, 257 sizeof(struct proc_maps_private)); 258 } 259 260 /* 261 * Indicate if the VMA is a stack for the given task; for 262 * /proc/PID/maps that is the stack of the main task. 263 */ 264 static int is_stack(struct vm_area_struct *vma) 265 { 266 /* 267 * We make no effort to guess what a given thread considers to be 268 * its "stack". It's not even well-defined for programs written 269 * languages like Go. 270 */ 271 return vma->vm_start <= vma->vm_mm->start_stack && 272 vma->vm_end >= vma->vm_mm->start_stack; 273 } 274 275 static void show_vma_header_prefix(struct seq_file *m, 276 unsigned long start, unsigned long end, 277 vm_flags_t flags, unsigned long long pgoff, 278 dev_t dev, unsigned long ino) 279 { 280 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 281 seq_put_hex_ll(m, NULL, start, 8); 282 seq_put_hex_ll(m, "-", end, 8); 283 seq_putc(m, ' '); 284 seq_putc(m, flags & VM_READ ? 'r' : '-'); 285 seq_putc(m, flags & VM_WRITE ? 'w' : '-'); 286 seq_putc(m, flags & VM_EXEC ? 'x' : '-'); 287 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p'); 288 seq_put_hex_ll(m, " ", pgoff, 8); 289 seq_put_hex_ll(m, " ", MAJOR(dev), 2); 290 seq_put_hex_ll(m, ":", MINOR(dev), 2); 291 seq_put_decimal_ull(m, " ", ino); 292 seq_putc(m, ' '); 293 } 294 295 static void 296 show_map_vma(struct seq_file *m, struct vm_area_struct *vma) 297 { 298 struct mm_struct *mm = vma->vm_mm; 299 struct file *file = vma->vm_file; 300 vm_flags_t flags = vma->vm_flags; 301 unsigned long ino = 0; 302 unsigned long long pgoff = 0; 303 unsigned long start, end; 304 dev_t dev = 0; 305 const char *name = NULL; 306 307 if (file) { 308 struct inode *inode = file_inode(vma->vm_file); 309 dev = inode->i_sb->s_dev; 310 ino = inode->i_ino; 311 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 312 } 313 314 start = vma->vm_start; 315 end = vma->vm_end; 316 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 317 318 /* 319 * Print the dentry name for named mappings, and a 320 * special [heap] marker for the heap: 321 */ 322 if (file) { 323 seq_pad(m, ' '); 324 seq_file_path(m, file, "\n"); 325 goto done; 326 } 327 328 if (vma->vm_ops && vma->vm_ops->name) { 329 name = vma->vm_ops->name(vma); 330 if (name) 331 goto done; 332 } 333 334 name = arch_vma_name(vma); 335 if (!name) { 336 if (!mm) { 337 name = "[vdso]"; 338 goto done; 339 } 340 341 if (vma->vm_start <= mm->brk && 342 vma->vm_end >= mm->start_brk) { 343 name = "[heap]"; 344 goto done; 345 } 346 347 if (is_stack(vma)) 348 name = "[stack]"; 349 } 350 351 done: 352 if (name) { 353 seq_pad(m, ' '); 354 seq_puts(m, name); 355 } 356 seq_putc(m, '\n'); 357 } 358 359 static int show_map(struct seq_file *m, void *v) 360 { 361 show_map_vma(m, v); 362 m_cache_vma(m, v); 363 return 0; 364 } 365 366 static const struct seq_operations proc_pid_maps_op = { 367 .start = m_start, 368 .next = m_next, 369 .stop = m_stop, 370 .show = show_map 371 }; 372 373 static int pid_maps_open(struct inode *inode, struct file *file) 374 { 375 return do_maps_open(inode, file, &proc_pid_maps_op); 376 } 377 378 const struct file_operations proc_pid_maps_operations = { 379 .open = pid_maps_open, 380 .read = seq_read, 381 .llseek = seq_lseek, 382 .release = proc_map_release, 383 }; 384 385 /* 386 * Proportional Set Size(PSS): my share of RSS. 387 * 388 * PSS of a process is the count of pages it has in memory, where each 389 * page is divided by the number of processes sharing it. So if a 390 * process has 1000 pages all to itself, and 1000 shared with one other 391 * process, its PSS will be 1500. 392 * 393 * To keep (accumulated) division errors low, we adopt a 64bit 394 * fixed-point pss counter to minimize division errors. So (pss >> 395 * PSS_SHIFT) would be the real byte count. 396 * 397 * A shift of 12 before division means (assuming 4K page size): 398 * - 1M 3-user-pages add up to 8KB errors; 399 * - supports mapcount up to 2^24, or 16M; 400 * - supports PSS up to 2^52 bytes, or 4PB. 401 */ 402 #define PSS_SHIFT 12 403 404 #ifdef CONFIG_PROC_PAGE_MONITOR 405 struct mem_size_stats { 406 unsigned long resident; 407 unsigned long shared_clean; 408 unsigned long shared_dirty; 409 unsigned long private_clean; 410 unsigned long private_dirty; 411 unsigned long referenced; 412 unsigned long anonymous; 413 unsigned long lazyfree; 414 unsigned long anonymous_thp; 415 unsigned long shmem_thp; 416 unsigned long swap; 417 unsigned long shared_hugetlb; 418 unsigned long private_hugetlb; 419 u64 pss; 420 u64 pss_locked; 421 u64 swap_pss; 422 bool check_shmem_swap; 423 }; 424 425 static void smaps_account(struct mem_size_stats *mss, struct page *page, 426 bool compound, bool young, bool dirty) 427 { 428 int i, nr = compound ? 1 << compound_order(page) : 1; 429 unsigned long size = nr * PAGE_SIZE; 430 431 if (PageAnon(page)) { 432 mss->anonymous += size; 433 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 434 mss->lazyfree += size; 435 } 436 437 mss->resident += size; 438 /* Accumulate the size in pages that have been accessed. */ 439 if (young || page_is_young(page) || PageReferenced(page)) 440 mss->referenced += size; 441 442 /* 443 * page_count(page) == 1 guarantees the page is mapped exactly once. 444 * If any subpage of the compound page mapped with PTE it would elevate 445 * page_count(). 446 */ 447 if (page_count(page) == 1) { 448 if (dirty || PageDirty(page)) 449 mss->private_dirty += size; 450 else 451 mss->private_clean += size; 452 mss->pss += (u64)size << PSS_SHIFT; 453 return; 454 } 455 456 for (i = 0; i < nr; i++, page++) { 457 int mapcount = page_mapcount(page); 458 459 if (mapcount >= 2) { 460 if (dirty || PageDirty(page)) 461 mss->shared_dirty += PAGE_SIZE; 462 else 463 mss->shared_clean += PAGE_SIZE; 464 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount; 465 } else { 466 if (dirty || PageDirty(page)) 467 mss->private_dirty += PAGE_SIZE; 468 else 469 mss->private_clean += PAGE_SIZE; 470 mss->pss += PAGE_SIZE << PSS_SHIFT; 471 } 472 } 473 } 474 475 #ifdef CONFIG_SHMEM 476 static int smaps_pte_hole(unsigned long addr, unsigned long end, 477 struct mm_walk *walk) 478 { 479 struct mem_size_stats *mss = walk->private; 480 481 mss->swap += shmem_partial_swap_usage( 482 walk->vma->vm_file->f_mapping, addr, end); 483 484 return 0; 485 } 486 #endif 487 488 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 489 struct mm_walk *walk) 490 { 491 struct mem_size_stats *mss = walk->private; 492 struct vm_area_struct *vma = walk->vma; 493 struct page *page = NULL; 494 495 if (pte_present(*pte)) { 496 page = vm_normal_page(vma, addr, *pte); 497 } else if (is_swap_pte(*pte)) { 498 swp_entry_t swpent = pte_to_swp_entry(*pte); 499 500 if (!non_swap_entry(swpent)) { 501 int mapcount; 502 503 mss->swap += PAGE_SIZE; 504 mapcount = swp_swapcount(swpent); 505 if (mapcount >= 2) { 506 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 507 508 do_div(pss_delta, mapcount); 509 mss->swap_pss += pss_delta; 510 } else { 511 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 512 } 513 } else if (is_migration_entry(swpent)) 514 page = migration_entry_to_page(swpent); 515 else if (is_device_private_entry(swpent)) 516 page = device_private_entry_to_page(swpent); 517 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 518 && pte_none(*pte))) { 519 page = find_get_entry(vma->vm_file->f_mapping, 520 linear_page_index(vma, addr)); 521 if (!page) 522 return; 523 524 if (xa_is_value(page)) 525 mss->swap += PAGE_SIZE; 526 else 527 put_page(page); 528 529 return; 530 } 531 532 if (!page) 533 return; 534 535 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte)); 536 } 537 538 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 539 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 540 struct mm_walk *walk) 541 { 542 struct mem_size_stats *mss = walk->private; 543 struct vm_area_struct *vma = walk->vma; 544 struct page *page; 545 546 /* FOLL_DUMP will return -EFAULT on huge zero page */ 547 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 548 if (IS_ERR_OR_NULL(page)) 549 return; 550 if (PageAnon(page)) 551 mss->anonymous_thp += HPAGE_PMD_SIZE; 552 else if (PageSwapBacked(page)) 553 mss->shmem_thp += HPAGE_PMD_SIZE; 554 else if (is_zone_device_page(page)) 555 /* pass */; 556 else 557 VM_BUG_ON_PAGE(1, page); 558 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd)); 559 } 560 #else 561 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 562 struct mm_walk *walk) 563 { 564 } 565 #endif 566 567 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 568 struct mm_walk *walk) 569 { 570 struct vm_area_struct *vma = walk->vma; 571 pte_t *pte; 572 spinlock_t *ptl; 573 574 ptl = pmd_trans_huge_lock(pmd, vma); 575 if (ptl) { 576 if (pmd_present(*pmd)) 577 smaps_pmd_entry(pmd, addr, walk); 578 spin_unlock(ptl); 579 goto out; 580 } 581 582 if (pmd_trans_unstable(pmd)) 583 goto out; 584 /* 585 * The mmap_sem held all the way back in m_start() is what 586 * keeps khugepaged out of here and from collapsing things 587 * in here. 588 */ 589 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 590 for (; addr != end; pte++, addr += PAGE_SIZE) 591 smaps_pte_entry(pte, addr, walk); 592 pte_unmap_unlock(pte - 1, ptl); 593 out: 594 cond_resched(); 595 return 0; 596 } 597 598 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 599 { 600 /* 601 * Don't forget to update Documentation/ on changes. 602 */ 603 static const char mnemonics[BITS_PER_LONG][2] = { 604 /* 605 * In case if we meet a flag we don't know about. 606 */ 607 [0 ... (BITS_PER_LONG-1)] = "??", 608 609 [ilog2(VM_READ)] = "rd", 610 [ilog2(VM_WRITE)] = "wr", 611 [ilog2(VM_EXEC)] = "ex", 612 [ilog2(VM_SHARED)] = "sh", 613 [ilog2(VM_MAYREAD)] = "mr", 614 [ilog2(VM_MAYWRITE)] = "mw", 615 [ilog2(VM_MAYEXEC)] = "me", 616 [ilog2(VM_MAYSHARE)] = "ms", 617 [ilog2(VM_GROWSDOWN)] = "gd", 618 [ilog2(VM_PFNMAP)] = "pf", 619 [ilog2(VM_DENYWRITE)] = "dw", 620 #ifdef CONFIG_X86_INTEL_MPX 621 [ilog2(VM_MPX)] = "mp", 622 #endif 623 [ilog2(VM_LOCKED)] = "lo", 624 [ilog2(VM_IO)] = "io", 625 [ilog2(VM_SEQ_READ)] = "sr", 626 [ilog2(VM_RAND_READ)] = "rr", 627 [ilog2(VM_DONTCOPY)] = "dc", 628 [ilog2(VM_DONTEXPAND)] = "de", 629 [ilog2(VM_ACCOUNT)] = "ac", 630 [ilog2(VM_NORESERVE)] = "nr", 631 [ilog2(VM_HUGETLB)] = "ht", 632 [ilog2(VM_SYNC)] = "sf", 633 [ilog2(VM_ARCH_1)] = "ar", 634 [ilog2(VM_WIPEONFORK)] = "wf", 635 [ilog2(VM_DONTDUMP)] = "dd", 636 #ifdef CONFIG_MEM_SOFT_DIRTY 637 [ilog2(VM_SOFTDIRTY)] = "sd", 638 #endif 639 [ilog2(VM_MIXEDMAP)] = "mm", 640 [ilog2(VM_HUGEPAGE)] = "hg", 641 [ilog2(VM_NOHUGEPAGE)] = "nh", 642 [ilog2(VM_MERGEABLE)] = "mg", 643 [ilog2(VM_UFFD_MISSING)]= "um", 644 [ilog2(VM_UFFD_WP)] = "uw", 645 #ifdef CONFIG_ARCH_HAS_PKEYS 646 /* These come out via ProtectionKey: */ 647 [ilog2(VM_PKEY_BIT0)] = "", 648 [ilog2(VM_PKEY_BIT1)] = "", 649 [ilog2(VM_PKEY_BIT2)] = "", 650 [ilog2(VM_PKEY_BIT3)] = "", 651 #if VM_PKEY_BIT4 652 [ilog2(VM_PKEY_BIT4)] = "", 653 #endif 654 #endif /* CONFIG_ARCH_HAS_PKEYS */ 655 }; 656 size_t i; 657 658 seq_puts(m, "VmFlags: "); 659 for (i = 0; i < BITS_PER_LONG; i++) { 660 if (!mnemonics[i][0]) 661 continue; 662 if (vma->vm_flags & (1UL << i)) { 663 seq_putc(m, mnemonics[i][0]); 664 seq_putc(m, mnemonics[i][1]); 665 seq_putc(m, ' '); 666 } 667 } 668 seq_putc(m, '\n'); 669 } 670 671 #ifdef CONFIG_HUGETLB_PAGE 672 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 673 unsigned long addr, unsigned long end, 674 struct mm_walk *walk) 675 { 676 struct mem_size_stats *mss = walk->private; 677 struct vm_area_struct *vma = walk->vma; 678 struct page *page = NULL; 679 680 if (pte_present(*pte)) { 681 page = vm_normal_page(vma, addr, *pte); 682 } else if (is_swap_pte(*pte)) { 683 swp_entry_t swpent = pte_to_swp_entry(*pte); 684 685 if (is_migration_entry(swpent)) 686 page = migration_entry_to_page(swpent); 687 else if (is_device_private_entry(swpent)) 688 page = device_private_entry_to_page(swpent); 689 } 690 if (page) { 691 int mapcount = page_mapcount(page); 692 693 if (mapcount >= 2) 694 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 695 else 696 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 697 } 698 return 0; 699 } 700 #endif /* HUGETLB_PAGE */ 701 702 static void smap_gather_stats(struct vm_area_struct *vma, 703 struct mem_size_stats *mss) 704 { 705 struct mm_walk smaps_walk = { 706 .pmd_entry = smaps_pte_range, 707 #ifdef CONFIG_HUGETLB_PAGE 708 .hugetlb_entry = smaps_hugetlb_range, 709 #endif 710 .mm = vma->vm_mm, 711 }; 712 713 smaps_walk.private = mss; 714 715 #ifdef CONFIG_SHMEM 716 /* In case of smaps_rollup, reset the value from previous vma */ 717 mss->check_shmem_swap = false; 718 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 719 /* 720 * For shared or readonly shmem mappings we know that all 721 * swapped out pages belong to the shmem object, and we can 722 * obtain the swap value much more efficiently. For private 723 * writable mappings, we might have COW pages that are 724 * not affected by the parent swapped out pages of the shmem 725 * object, so we have to distinguish them during the page walk. 726 * Unless we know that the shmem object (or the part mapped by 727 * our VMA) has no swapped out pages at all. 728 */ 729 unsigned long shmem_swapped = shmem_swap_usage(vma); 730 731 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 732 !(vma->vm_flags & VM_WRITE)) { 733 mss->swap += shmem_swapped; 734 } else { 735 mss->check_shmem_swap = true; 736 smaps_walk.pte_hole = smaps_pte_hole; 737 } 738 } 739 #endif 740 741 /* mmap_sem is held in m_start */ 742 walk_page_vma(vma, &smaps_walk); 743 if (vma->vm_flags & VM_LOCKED) 744 mss->pss_locked += mss->pss; 745 } 746 747 #define SEQ_PUT_DEC(str, val) \ 748 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 749 750 /* Show the contents common for smaps and smaps_rollup */ 751 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss) 752 { 753 SEQ_PUT_DEC("Rss: ", mss->resident); 754 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 755 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 756 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 757 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 758 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 759 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 760 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 761 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 762 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 763 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 764 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 765 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 766 mss->private_hugetlb >> 10, 7); 767 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 768 SEQ_PUT_DEC(" kB\nSwapPss: ", 769 mss->swap_pss >> PSS_SHIFT); 770 SEQ_PUT_DEC(" kB\nLocked: ", 771 mss->pss_locked >> PSS_SHIFT); 772 seq_puts(m, " kB\n"); 773 } 774 775 static int show_smap(struct seq_file *m, void *v) 776 { 777 struct vm_area_struct *vma = v; 778 struct mem_size_stats mss; 779 780 memset(&mss, 0, sizeof(mss)); 781 782 smap_gather_stats(vma, &mss); 783 784 show_map_vma(m, vma); 785 786 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 787 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 788 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 789 seq_puts(m, " kB\n"); 790 791 __show_smap(m, &mss); 792 793 seq_printf(m, "THPeligible: %d\n", transparent_hugepage_enabled(vma)); 794 795 if (arch_pkeys_enabled()) 796 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 797 show_smap_vma_flags(m, vma); 798 799 m_cache_vma(m, vma); 800 801 return 0; 802 } 803 804 static int show_smaps_rollup(struct seq_file *m, void *v) 805 { 806 struct proc_maps_private *priv = m->private; 807 struct mem_size_stats mss; 808 struct mm_struct *mm; 809 struct vm_area_struct *vma; 810 unsigned long last_vma_end = 0; 811 int ret = 0; 812 813 priv->task = get_proc_task(priv->inode); 814 if (!priv->task) 815 return -ESRCH; 816 817 mm = priv->mm; 818 if (!mm || !mmget_not_zero(mm)) { 819 ret = -ESRCH; 820 goto out_put_task; 821 } 822 823 memset(&mss, 0, sizeof(mss)); 824 825 down_read(&mm->mmap_sem); 826 hold_task_mempolicy(priv); 827 828 for (vma = priv->mm->mmap; vma; vma = vma->vm_next) { 829 smap_gather_stats(vma, &mss); 830 last_vma_end = vma->vm_end; 831 } 832 833 show_vma_header_prefix(m, priv->mm->mmap->vm_start, 834 last_vma_end, 0, 0, 0, 0); 835 seq_pad(m, ' '); 836 seq_puts(m, "[rollup]\n"); 837 838 __show_smap(m, &mss); 839 840 release_task_mempolicy(priv); 841 up_read(&mm->mmap_sem); 842 mmput(mm); 843 844 out_put_task: 845 put_task_struct(priv->task); 846 priv->task = NULL; 847 848 return ret; 849 } 850 #undef SEQ_PUT_DEC 851 852 static const struct seq_operations proc_pid_smaps_op = { 853 .start = m_start, 854 .next = m_next, 855 .stop = m_stop, 856 .show = show_smap 857 }; 858 859 static int pid_smaps_open(struct inode *inode, struct file *file) 860 { 861 return do_maps_open(inode, file, &proc_pid_smaps_op); 862 } 863 864 static int smaps_rollup_open(struct inode *inode, struct file *file) 865 { 866 int ret; 867 struct proc_maps_private *priv; 868 869 priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT); 870 if (!priv) 871 return -ENOMEM; 872 873 ret = single_open(file, show_smaps_rollup, priv); 874 if (ret) 875 goto out_free; 876 877 priv->inode = inode; 878 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 879 if (IS_ERR(priv->mm)) { 880 ret = PTR_ERR(priv->mm); 881 882 single_release(inode, file); 883 goto out_free; 884 } 885 886 return 0; 887 888 out_free: 889 kfree(priv); 890 return ret; 891 } 892 893 static int smaps_rollup_release(struct inode *inode, struct file *file) 894 { 895 struct seq_file *seq = file->private_data; 896 struct proc_maps_private *priv = seq->private; 897 898 if (priv->mm) 899 mmdrop(priv->mm); 900 901 kfree(priv); 902 return single_release(inode, file); 903 } 904 905 const struct file_operations proc_pid_smaps_operations = { 906 .open = pid_smaps_open, 907 .read = seq_read, 908 .llseek = seq_lseek, 909 .release = proc_map_release, 910 }; 911 912 const struct file_operations proc_pid_smaps_rollup_operations = { 913 .open = smaps_rollup_open, 914 .read = seq_read, 915 .llseek = seq_lseek, 916 .release = smaps_rollup_release, 917 }; 918 919 enum clear_refs_types { 920 CLEAR_REFS_ALL = 1, 921 CLEAR_REFS_ANON, 922 CLEAR_REFS_MAPPED, 923 CLEAR_REFS_SOFT_DIRTY, 924 CLEAR_REFS_MM_HIWATER_RSS, 925 CLEAR_REFS_LAST, 926 }; 927 928 struct clear_refs_private { 929 enum clear_refs_types type; 930 }; 931 932 #ifdef CONFIG_MEM_SOFT_DIRTY 933 static inline void clear_soft_dirty(struct vm_area_struct *vma, 934 unsigned long addr, pte_t *pte) 935 { 936 /* 937 * The soft-dirty tracker uses #PF-s to catch writes 938 * to pages, so write-protect the pte as well. See the 939 * Documentation/admin-guide/mm/soft-dirty.rst for full description 940 * of how soft-dirty works. 941 */ 942 pte_t ptent = *pte; 943 944 if (pte_present(ptent)) { 945 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte); 946 ptent = pte_wrprotect(ptent); 947 ptent = pte_clear_soft_dirty(ptent); 948 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent); 949 } else if (is_swap_pte(ptent)) { 950 ptent = pte_swp_clear_soft_dirty(ptent); 951 set_pte_at(vma->vm_mm, addr, pte, ptent); 952 } 953 } 954 #else 955 static inline void clear_soft_dirty(struct vm_area_struct *vma, 956 unsigned long addr, pte_t *pte) 957 { 958 } 959 #endif 960 961 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 962 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 963 unsigned long addr, pmd_t *pmdp) 964 { 965 pmd_t old, pmd = *pmdp; 966 967 if (pmd_present(pmd)) { 968 /* See comment in change_huge_pmd() */ 969 old = pmdp_invalidate(vma, addr, pmdp); 970 if (pmd_dirty(old)) 971 pmd = pmd_mkdirty(pmd); 972 if (pmd_young(old)) 973 pmd = pmd_mkyoung(pmd); 974 975 pmd = pmd_wrprotect(pmd); 976 pmd = pmd_clear_soft_dirty(pmd); 977 978 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 979 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 980 pmd = pmd_swp_clear_soft_dirty(pmd); 981 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 982 } 983 } 984 #else 985 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 986 unsigned long addr, pmd_t *pmdp) 987 { 988 } 989 #endif 990 991 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 992 unsigned long end, struct mm_walk *walk) 993 { 994 struct clear_refs_private *cp = walk->private; 995 struct vm_area_struct *vma = walk->vma; 996 pte_t *pte, ptent; 997 spinlock_t *ptl; 998 struct page *page; 999 1000 ptl = pmd_trans_huge_lock(pmd, vma); 1001 if (ptl) { 1002 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1003 clear_soft_dirty_pmd(vma, addr, pmd); 1004 goto out; 1005 } 1006 1007 if (!pmd_present(*pmd)) 1008 goto out; 1009 1010 page = pmd_page(*pmd); 1011 1012 /* Clear accessed and referenced bits. */ 1013 pmdp_test_and_clear_young(vma, addr, pmd); 1014 test_and_clear_page_young(page); 1015 ClearPageReferenced(page); 1016 out: 1017 spin_unlock(ptl); 1018 return 0; 1019 } 1020 1021 if (pmd_trans_unstable(pmd)) 1022 return 0; 1023 1024 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1025 for (; addr != end; pte++, addr += PAGE_SIZE) { 1026 ptent = *pte; 1027 1028 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1029 clear_soft_dirty(vma, addr, pte); 1030 continue; 1031 } 1032 1033 if (!pte_present(ptent)) 1034 continue; 1035 1036 page = vm_normal_page(vma, addr, ptent); 1037 if (!page) 1038 continue; 1039 1040 /* Clear accessed and referenced bits. */ 1041 ptep_test_and_clear_young(vma, addr, pte); 1042 test_and_clear_page_young(page); 1043 ClearPageReferenced(page); 1044 } 1045 pte_unmap_unlock(pte - 1, ptl); 1046 cond_resched(); 1047 return 0; 1048 } 1049 1050 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1051 struct mm_walk *walk) 1052 { 1053 struct clear_refs_private *cp = walk->private; 1054 struct vm_area_struct *vma = walk->vma; 1055 1056 if (vma->vm_flags & VM_PFNMAP) 1057 return 1; 1058 1059 /* 1060 * Writing 1 to /proc/pid/clear_refs affects all pages. 1061 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1062 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1063 * Writing 4 to /proc/pid/clear_refs affects all pages. 1064 */ 1065 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1066 return 1; 1067 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1068 return 1; 1069 return 0; 1070 } 1071 1072 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1073 size_t count, loff_t *ppos) 1074 { 1075 struct task_struct *task; 1076 char buffer[PROC_NUMBUF]; 1077 struct mm_struct *mm; 1078 struct vm_area_struct *vma; 1079 enum clear_refs_types type; 1080 struct mmu_gather tlb; 1081 int itype; 1082 int rv; 1083 1084 memset(buffer, 0, sizeof(buffer)); 1085 if (count > sizeof(buffer) - 1) 1086 count = sizeof(buffer) - 1; 1087 if (copy_from_user(buffer, buf, count)) 1088 return -EFAULT; 1089 rv = kstrtoint(strstrip(buffer), 10, &itype); 1090 if (rv < 0) 1091 return rv; 1092 type = (enum clear_refs_types)itype; 1093 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1094 return -EINVAL; 1095 1096 task = get_proc_task(file_inode(file)); 1097 if (!task) 1098 return -ESRCH; 1099 mm = get_task_mm(task); 1100 if (mm) { 1101 struct mmu_notifier_range range; 1102 struct clear_refs_private cp = { 1103 .type = type, 1104 }; 1105 struct mm_walk clear_refs_walk = { 1106 .pmd_entry = clear_refs_pte_range, 1107 .test_walk = clear_refs_test_walk, 1108 .mm = mm, 1109 .private = &cp, 1110 }; 1111 1112 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1113 if (down_write_killable(&mm->mmap_sem)) { 1114 count = -EINTR; 1115 goto out_mm; 1116 } 1117 1118 /* 1119 * Writing 5 to /proc/pid/clear_refs resets the peak 1120 * resident set size to this mm's current rss value. 1121 */ 1122 reset_mm_hiwater_rss(mm); 1123 up_write(&mm->mmap_sem); 1124 goto out_mm; 1125 } 1126 1127 down_read(&mm->mmap_sem); 1128 tlb_gather_mmu(&tlb, mm, 0, -1); 1129 if (type == CLEAR_REFS_SOFT_DIRTY) { 1130 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1131 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1132 continue; 1133 up_read(&mm->mmap_sem); 1134 if (down_write_killable(&mm->mmap_sem)) { 1135 count = -EINTR; 1136 goto out_mm; 1137 } 1138 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1139 vma->vm_flags &= ~VM_SOFTDIRTY; 1140 vma_set_page_prot(vma); 1141 } 1142 downgrade_write(&mm->mmap_sem); 1143 break; 1144 } 1145 1146 mmu_notifier_range_init(&range, mm, 0, -1UL); 1147 mmu_notifier_invalidate_range_start(&range); 1148 } 1149 walk_page_range(0, mm->highest_vm_end, &clear_refs_walk); 1150 if (type == CLEAR_REFS_SOFT_DIRTY) 1151 mmu_notifier_invalidate_range_end(&range); 1152 tlb_finish_mmu(&tlb, 0, -1); 1153 up_read(&mm->mmap_sem); 1154 out_mm: 1155 mmput(mm); 1156 } 1157 put_task_struct(task); 1158 1159 return count; 1160 } 1161 1162 const struct file_operations proc_clear_refs_operations = { 1163 .write = clear_refs_write, 1164 .llseek = noop_llseek, 1165 }; 1166 1167 typedef struct { 1168 u64 pme; 1169 } pagemap_entry_t; 1170 1171 struct pagemapread { 1172 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1173 pagemap_entry_t *buffer; 1174 bool show_pfn; 1175 }; 1176 1177 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1178 #define PAGEMAP_WALK_MASK (PMD_MASK) 1179 1180 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1181 #define PM_PFRAME_BITS 55 1182 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1183 #define PM_SOFT_DIRTY BIT_ULL(55) 1184 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1185 #define PM_FILE BIT_ULL(61) 1186 #define PM_SWAP BIT_ULL(62) 1187 #define PM_PRESENT BIT_ULL(63) 1188 1189 #define PM_END_OF_BUFFER 1 1190 1191 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1192 { 1193 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1194 } 1195 1196 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1197 struct pagemapread *pm) 1198 { 1199 pm->buffer[pm->pos++] = *pme; 1200 if (pm->pos >= pm->len) 1201 return PM_END_OF_BUFFER; 1202 return 0; 1203 } 1204 1205 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1206 struct mm_walk *walk) 1207 { 1208 struct pagemapread *pm = walk->private; 1209 unsigned long addr = start; 1210 int err = 0; 1211 1212 while (addr < end) { 1213 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1214 pagemap_entry_t pme = make_pme(0, 0); 1215 /* End of address space hole, which we mark as non-present. */ 1216 unsigned long hole_end; 1217 1218 if (vma) 1219 hole_end = min(end, vma->vm_start); 1220 else 1221 hole_end = end; 1222 1223 for (; addr < hole_end; addr += PAGE_SIZE) { 1224 err = add_to_pagemap(addr, &pme, pm); 1225 if (err) 1226 goto out; 1227 } 1228 1229 if (!vma) 1230 break; 1231 1232 /* Addresses in the VMA. */ 1233 if (vma->vm_flags & VM_SOFTDIRTY) 1234 pme = make_pme(0, PM_SOFT_DIRTY); 1235 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1236 err = add_to_pagemap(addr, &pme, pm); 1237 if (err) 1238 goto out; 1239 } 1240 } 1241 out: 1242 return err; 1243 } 1244 1245 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1246 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1247 { 1248 u64 frame = 0, flags = 0; 1249 struct page *page = NULL; 1250 1251 if (pte_present(pte)) { 1252 if (pm->show_pfn) 1253 frame = pte_pfn(pte); 1254 flags |= PM_PRESENT; 1255 page = _vm_normal_page(vma, addr, pte, true); 1256 if (pte_soft_dirty(pte)) 1257 flags |= PM_SOFT_DIRTY; 1258 } else if (is_swap_pte(pte)) { 1259 swp_entry_t entry; 1260 if (pte_swp_soft_dirty(pte)) 1261 flags |= PM_SOFT_DIRTY; 1262 entry = pte_to_swp_entry(pte); 1263 if (pm->show_pfn) 1264 frame = swp_type(entry) | 1265 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1266 flags |= PM_SWAP; 1267 if (is_migration_entry(entry)) 1268 page = migration_entry_to_page(entry); 1269 1270 if (is_device_private_entry(entry)) 1271 page = device_private_entry_to_page(entry); 1272 } 1273 1274 if (page && !PageAnon(page)) 1275 flags |= PM_FILE; 1276 if (page && page_mapcount(page) == 1) 1277 flags |= PM_MMAP_EXCLUSIVE; 1278 if (vma->vm_flags & VM_SOFTDIRTY) 1279 flags |= PM_SOFT_DIRTY; 1280 1281 return make_pme(frame, flags); 1282 } 1283 1284 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1285 struct mm_walk *walk) 1286 { 1287 struct vm_area_struct *vma = walk->vma; 1288 struct pagemapread *pm = walk->private; 1289 spinlock_t *ptl; 1290 pte_t *pte, *orig_pte; 1291 int err = 0; 1292 1293 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1294 ptl = pmd_trans_huge_lock(pmdp, vma); 1295 if (ptl) { 1296 u64 flags = 0, frame = 0; 1297 pmd_t pmd = *pmdp; 1298 struct page *page = NULL; 1299 1300 if (vma->vm_flags & VM_SOFTDIRTY) 1301 flags |= PM_SOFT_DIRTY; 1302 1303 if (pmd_present(pmd)) { 1304 page = pmd_page(pmd); 1305 1306 flags |= PM_PRESENT; 1307 if (pmd_soft_dirty(pmd)) 1308 flags |= PM_SOFT_DIRTY; 1309 if (pm->show_pfn) 1310 frame = pmd_pfn(pmd) + 1311 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1312 } 1313 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1314 else if (is_swap_pmd(pmd)) { 1315 swp_entry_t entry = pmd_to_swp_entry(pmd); 1316 unsigned long offset; 1317 1318 if (pm->show_pfn) { 1319 offset = swp_offset(entry) + 1320 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1321 frame = swp_type(entry) | 1322 (offset << MAX_SWAPFILES_SHIFT); 1323 } 1324 flags |= PM_SWAP; 1325 if (pmd_swp_soft_dirty(pmd)) 1326 flags |= PM_SOFT_DIRTY; 1327 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1328 page = migration_entry_to_page(entry); 1329 } 1330 #endif 1331 1332 if (page && page_mapcount(page) == 1) 1333 flags |= PM_MMAP_EXCLUSIVE; 1334 1335 for (; addr != end; addr += PAGE_SIZE) { 1336 pagemap_entry_t pme = make_pme(frame, flags); 1337 1338 err = add_to_pagemap(addr, &pme, pm); 1339 if (err) 1340 break; 1341 if (pm->show_pfn) { 1342 if (flags & PM_PRESENT) 1343 frame++; 1344 else if (flags & PM_SWAP) 1345 frame += (1 << MAX_SWAPFILES_SHIFT); 1346 } 1347 } 1348 spin_unlock(ptl); 1349 return err; 1350 } 1351 1352 if (pmd_trans_unstable(pmdp)) 1353 return 0; 1354 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1355 1356 /* 1357 * We can assume that @vma always points to a valid one and @end never 1358 * goes beyond vma->vm_end. 1359 */ 1360 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1361 for (; addr < end; pte++, addr += PAGE_SIZE) { 1362 pagemap_entry_t pme; 1363 1364 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1365 err = add_to_pagemap(addr, &pme, pm); 1366 if (err) 1367 break; 1368 } 1369 pte_unmap_unlock(orig_pte, ptl); 1370 1371 cond_resched(); 1372 1373 return err; 1374 } 1375 1376 #ifdef CONFIG_HUGETLB_PAGE 1377 /* This function walks within one hugetlb entry in the single call */ 1378 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1379 unsigned long addr, unsigned long end, 1380 struct mm_walk *walk) 1381 { 1382 struct pagemapread *pm = walk->private; 1383 struct vm_area_struct *vma = walk->vma; 1384 u64 flags = 0, frame = 0; 1385 int err = 0; 1386 pte_t pte; 1387 1388 if (vma->vm_flags & VM_SOFTDIRTY) 1389 flags |= PM_SOFT_DIRTY; 1390 1391 pte = huge_ptep_get(ptep); 1392 if (pte_present(pte)) { 1393 struct page *page = pte_page(pte); 1394 1395 if (!PageAnon(page)) 1396 flags |= PM_FILE; 1397 1398 if (page_mapcount(page) == 1) 1399 flags |= PM_MMAP_EXCLUSIVE; 1400 1401 flags |= PM_PRESENT; 1402 if (pm->show_pfn) 1403 frame = pte_pfn(pte) + 1404 ((addr & ~hmask) >> PAGE_SHIFT); 1405 } 1406 1407 for (; addr != end; addr += PAGE_SIZE) { 1408 pagemap_entry_t pme = make_pme(frame, flags); 1409 1410 err = add_to_pagemap(addr, &pme, pm); 1411 if (err) 1412 return err; 1413 if (pm->show_pfn && (flags & PM_PRESENT)) 1414 frame++; 1415 } 1416 1417 cond_resched(); 1418 1419 return err; 1420 } 1421 #endif /* HUGETLB_PAGE */ 1422 1423 /* 1424 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1425 * 1426 * For each page in the address space, this file contains one 64-bit entry 1427 * consisting of the following: 1428 * 1429 * Bits 0-54 page frame number (PFN) if present 1430 * Bits 0-4 swap type if swapped 1431 * Bits 5-54 swap offset if swapped 1432 * Bit 55 pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst) 1433 * Bit 56 page exclusively mapped 1434 * Bits 57-60 zero 1435 * Bit 61 page is file-page or shared-anon 1436 * Bit 62 page swapped 1437 * Bit 63 page present 1438 * 1439 * If the page is not present but in swap, then the PFN contains an 1440 * encoding of the swap file number and the page's offset into the 1441 * swap. Unmapped pages return a null PFN. This allows determining 1442 * precisely which pages are mapped (or in swap) and comparing mapped 1443 * pages between processes. 1444 * 1445 * Efficient users of this interface will use /proc/pid/maps to 1446 * determine which areas of memory are actually mapped and llseek to 1447 * skip over unmapped regions. 1448 */ 1449 static ssize_t pagemap_read(struct file *file, char __user *buf, 1450 size_t count, loff_t *ppos) 1451 { 1452 struct mm_struct *mm = file->private_data; 1453 struct pagemapread pm; 1454 struct mm_walk pagemap_walk = {}; 1455 unsigned long src; 1456 unsigned long svpfn; 1457 unsigned long start_vaddr; 1458 unsigned long end_vaddr; 1459 int ret = 0, copied = 0; 1460 1461 if (!mm || !mmget_not_zero(mm)) 1462 goto out; 1463 1464 ret = -EINVAL; 1465 /* file position must be aligned */ 1466 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1467 goto out_mm; 1468 1469 ret = 0; 1470 if (!count) 1471 goto out_mm; 1472 1473 /* do not disclose physical addresses: attack vector */ 1474 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1475 1476 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1477 pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL); 1478 ret = -ENOMEM; 1479 if (!pm.buffer) 1480 goto out_mm; 1481 1482 pagemap_walk.pmd_entry = pagemap_pmd_range; 1483 pagemap_walk.pte_hole = pagemap_pte_hole; 1484 #ifdef CONFIG_HUGETLB_PAGE 1485 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 1486 #endif 1487 pagemap_walk.mm = mm; 1488 pagemap_walk.private = ± 1489 1490 src = *ppos; 1491 svpfn = src / PM_ENTRY_BYTES; 1492 start_vaddr = svpfn << PAGE_SHIFT; 1493 end_vaddr = mm->task_size; 1494 1495 /* watch out for wraparound */ 1496 if (svpfn > mm->task_size >> PAGE_SHIFT) 1497 start_vaddr = end_vaddr; 1498 1499 /* 1500 * The odds are that this will stop walking way 1501 * before end_vaddr, because the length of the 1502 * user buffer is tracked in "pm", and the walk 1503 * will stop when we hit the end of the buffer. 1504 */ 1505 ret = 0; 1506 while (count && (start_vaddr < end_vaddr)) { 1507 int len; 1508 unsigned long end; 1509 1510 pm.pos = 0; 1511 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1512 /* overflow ? */ 1513 if (end < start_vaddr || end > end_vaddr) 1514 end = end_vaddr; 1515 down_read(&mm->mmap_sem); 1516 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 1517 up_read(&mm->mmap_sem); 1518 start_vaddr = end; 1519 1520 len = min(count, PM_ENTRY_BYTES * pm.pos); 1521 if (copy_to_user(buf, pm.buffer, len)) { 1522 ret = -EFAULT; 1523 goto out_free; 1524 } 1525 copied += len; 1526 buf += len; 1527 count -= len; 1528 } 1529 *ppos += copied; 1530 if (!ret || ret == PM_END_OF_BUFFER) 1531 ret = copied; 1532 1533 out_free: 1534 kfree(pm.buffer); 1535 out_mm: 1536 mmput(mm); 1537 out: 1538 return ret; 1539 } 1540 1541 static int pagemap_open(struct inode *inode, struct file *file) 1542 { 1543 struct mm_struct *mm; 1544 1545 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1546 if (IS_ERR(mm)) 1547 return PTR_ERR(mm); 1548 file->private_data = mm; 1549 return 0; 1550 } 1551 1552 static int pagemap_release(struct inode *inode, struct file *file) 1553 { 1554 struct mm_struct *mm = file->private_data; 1555 1556 if (mm) 1557 mmdrop(mm); 1558 return 0; 1559 } 1560 1561 const struct file_operations proc_pagemap_operations = { 1562 .llseek = mem_lseek, /* borrow this */ 1563 .read = pagemap_read, 1564 .open = pagemap_open, 1565 .release = pagemap_release, 1566 }; 1567 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1568 1569 #ifdef CONFIG_NUMA 1570 1571 struct numa_maps { 1572 unsigned long pages; 1573 unsigned long anon; 1574 unsigned long active; 1575 unsigned long writeback; 1576 unsigned long mapcount_max; 1577 unsigned long dirty; 1578 unsigned long swapcache; 1579 unsigned long node[MAX_NUMNODES]; 1580 }; 1581 1582 struct numa_maps_private { 1583 struct proc_maps_private proc_maps; 1584 struct numa_maps md; 1585 }; 1586 1587 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1588 unsigned long nr_pages) 1589 { 1590 int count = page_mapcount(page); 1591 1592 md->pages += nr_pages; 1593 if (pte_dirty || PageDirty(page)) 1594 md->dirty += nr_pages; 1595 1596 if (PageSwapCache(page)) 1597 md->swapcache += nr_pages; 1598 1599 if (PageActive(page) || PageUnevictable(page)) 1600 md->active += nr_pages; 1601 1602 if (PageWriteback(page)) 1603 md->writeback += nr_pages; 1604 1605 if (PageAnon(page)) 1606 md->anon += nr_pages; 1607 1608 if (count > md->mapcount_max) 1609 md->mapcount_max = count; 1610 1611 md->node[page_to_nid(page)] += nr_pages; 1612 } 1613 1614 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1615 unsigned long addr) 1616 { 1617 struct page *page; 1618 int nid; 1619 1620 if (!pte_present(pte)) 1621 return NULL; 1622 1623 page = vm_normal_page(vma, addr, pte); 1624 if (!page) 1625 return NULL; 1626 1627 if (PageReserved(page)) 1628 return NULL; 1629 1630 nid = page_to_nid(page); 1631 if (!node_isset(nid, node_states[N_MEMORY])) 1632 return NULL; 1633 1634 return page; 1635 } 1636 1637 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1638 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1639 struct vm_area_struct *vma, 1640 unsigned long addr) 1641 { 1642 struct page *page; 1643 int nid; 1644 1645 if (!pmd_present(pmd)) 1646 return NULL; 1647 1648 page = vm_normal_page_pmd(vma, addr, pmd); 1649 if (!page) 1650 return NULL; 1651 1652 if (PageReserved(page)) 1653 return NULL; 1654 1655 nid = page_to_nid(page); 1656 if (!node_isset(nid, node_states[N_MEMORY])) 1657 return NULL; 1658 1659 return page; 1660 } 1661 #endif 1662 1663 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1664 unsigned long end, struct mm_walk *walk) 1665 { 1666 struct numa_maps *md = walk->private; 1667 struct vm_area_struct *vma = walk->vma; 1668 spinlock_t *ptl; 1669 pte_t *orig_pte; 1670 pte_t *pte; 1671 1672 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1673 ptl = pmd_trans_huge_lock(pmd, vma); 1674 if (ptl) { 1675 struct page *page; 1676 1677 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1678 if (page) 1679 gather_stats(page, md, pmd_dirty(*pmd), 1680 HPAGE_PMD_SIZE/PAGE_SIZE); 1681 spin_unlock(ptl); 1682 return 0; 1683 } 1684 1685 if (pmd_trans_unstable(pmd)) 1686 return 0; 1687 #endif 1688 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1689 do { 1690 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1691 if (!page) 1692 continue; 1693 gather_stats(page, md, pte_dirty(*pte), 1); 1694 1695 } while (pte++, addr += PAGE_SIZE, addr != end); 1696 pte_unmap_unlock(orig_pte, ptl); 1697 cond_resched(); 1698 return 0; 1699 } 1700 #ifdef CONFIG_HUGETLB_PAGE 1701 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1702 unsigned long addr, unsigned long end, struct mm_walk *walk) 1703 { 1704 pte_t huge_pte = huge_ptep_get(pte); 1705 struct numa_maps *md; 1706 struct page *page; 1707 1708 if (!pte_present(huge_pte)) 1709 return 0; 1710 1711 page = pte_page(huge_pte); 1712 if (!page) 1713 return 0; 1714 1715 md = walk->private; 1716 gather_stats(page, md, pte_dirty(huge_pte), 1); 1717 return 0; 1718 } 1719 1720 #else 1721 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1722 unsigned long addr, unsigned long end, struct mm_walk *walk) 1723 { 1724 return 0; 1725 } 1726 #endif 1727 1728 /* 1729 * Display pages allocated per node and memory policy via /proc. 1730 */ 1731 static int show_numa_map(struct seq_file *m, void *v) 1732 { 1733 struct numa_maps_private *numa_priv = m->private; 1734 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1735 struct vm_area_struct *vma = v; 1736 struct numa_maps *md = &numa_priv->md; 1737 struct file *file = vma->vm_file; 1738 struct mm_struct *mm = vma->vm_mm; 1739 struct mm_walk walk = { 1740 .hugetlb_entry = gather_hugetlb_stats, 1741 .pmd_entry = gather_pte_stats, 1742 .private = md, 1743 .mm = mm, 1744 }; 1745 struct mempolicy *pol; 1746 char buffer[64]; 1747 int nid; 1748 1749 if (!mm) 1750 return 0; 1751 1752 /* Ensure we start with an empty set of numa_maps statistics. */ 1753 memset(md, 0, sizeof(*md)); 1754 1755 pol = __get_vma_policy(vma, vma->vm_start); 1756 if (pol) { 1757 mpol_to_str(buffer, sizeof(buffer), pol); 1758 mpol_cond_put(pol); 1759 } else { 1760 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1761 } 1762 1763 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1764 1765 if (file) { 1766 seq_puts(m, " file="); 1767 seq_file_path(m, file, "\n\t= "); 1768 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1769 seq_puts(m, " heap"); 1770 } else if (is_stack(vma)) { 1771 seq_puts(m, " stack"); 1772 } 1773 1774 if (is_vm_hugetlb_page(vma)) 1775 seq_puts(m, " huge"); 1776 1777 /* mmap_sem is held by m_start */ 1778 walk_page_vma(vma, &walk); 1779 1780 if (!md->pages) 1781 goto out; 1782 1783 if (md->anon) 1784 seq_printf(m, " anon=%lu", md->anon); 1785 1786 if (md->dirty) 1787 seq_printf(m, " dirty=%lu", md->dirty); 1788 1789 if (md->pages != md->anon && md->pages != md->dirty) 1790 seq_printf(m, " mapped=%lu", md->pages); 1791 1792 if (md->mapcount_max > 1) 1793 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1794 1795 if (md->swapcache) 1796 seq_printf(m, " swapcache=%lu", md->swapcache); 1797 1798 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1799 seq_printf(m, " active=%lu", md->active); 1800 1801 if (md->writeback) 1802 seq_printf(m, " writeback=%lu", md->writeback); 1803 1804 for_each_node_state(nid, N_MEMORY) 1805 if (md->node[nid]) 1806 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1807 1808 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1809 out: 1810 seq_putc(m, '\n'); 1811 m_cache_vma(m, vma); 1812 return 0; 1813 } 1814 1815 static const struct seq_operations proc_pid_numa_maps_op = { 1816 .start = m_start, 1817 .next = m_next, 1818 .stop = m_stop, 1819 .show = show_numa_map, 1820 }; 1821 1822 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1823 { 1824 return proc_maps_open(inode, file, &proc_pid_numa_maps_op, 1825 sizeof(struct numa_maps_private)); 1826 } 1827 1828 const struct file_operations proc_pid_numa_maps_operations = { 1829 .open = pid_numa_maps_open, 1830 .read = seq_read, 1831 .llseek = seq_lseek, 1832 .release = proc_map_release, 1833 }; 1834 1835 #endif /* CONFIG_NUMA */ 1836