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