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 kfree(priv->rollup); 251 return seq_release_private(inode, file); 252 } 253 254 static int do_maps_open(struct inode *inode, struct file *file, 255 const struct seq_operations *ops) 256 { 257 return proc_maps_open(inode, file, ops, 258 sizeof(struct proc_maps_private)); 259 } 260 261 /* 262 * Indicate if the VMA is a stack for the given task; for 263 * /proc/PID/maps that is the stack of the main task. 264 */ 265 static int is_stack(struct vm_area_struct *vma) 266 { 267 /* 268 * We make no effort to guess what a given thread considers to be 269 * its "stack". It's not even well-defined for programs written 270 * languages like Go. 271 */ 272 return vma->vm_start <= vma->vm_mm->start_stack && 273 vma->vm_end >= vma->vm_mm->start_stack; 274 } 275 276 static void show_vma_header_prefix(struct seq_file *m, 277 unsigned long start, unsigned long end, 278 vm_flags_t flags, unsigned long long pgoff, 279 dev_t dev, unsigned long ino) 280 { 281 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 282 seq_put_hex_ll(m, NULL, start, 8); 283 seq_put_hex_ll(m, "-", end, 8); 284 seq_putc(m, ' '); 285 seq_putc(m, flags & VM_READ ? 'r' : '-'); 286 seq_putc(m, flags & VM_WRITE ? 'w' : '-'); 287 seq_putc(m, flags & VM_EXEC ? 'x' : '-'); 288 seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p'); 289 seq_put_hex_ll(m, " ", pgoff, 8); 290 seq_put_hex_ll(m, " ", MAJOR(dev), 2); 291 seq_put_hex_ll(m, ":", MINOR(dev), 2); 292 seq_put_decimal_ull(m, " ", ino); 293 seq_putc(m, ' '); 294 } 295 296 static void 297 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid) 298 { 299 struct mm_struct *mm = vma->vm_mm; 300 struct file *file = vma->vm_file; 301 vm_flags_t flags = vma->vm_flags; 302 unsigned long ino = 0; 303 unsigned long long pgoff = 0; 304 unsigned long start, end; 305 dev_t dev = 0; 306 const char *name = NULL; 307 308 if (file) { 309 struct inode *inode = file_inode(vma->vm_file); 310 dev = inode->i_sb->s_dev; 311 ino = inode->i_ino; 312 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 313 } 314 315 start = vma->vm_start; 316 end = vma->vm_end; 317 show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino); 318 319 /* 320 * Print the dentry name for named mappings, and a 321 * special [heap] marker for the heap: 322 */ 323 if (file) { 324 seq_pad(m, ' '); 325 seq_file_path(m, file, "\n"); 326 goto done; 327 } 328 329 if (vma->vm_ops && vma->vm_ops->name) { 330 name = vma->vm_ops->name(vma); 331 if (name) 332 goto done; 333 } 334 335 name = arch_vma_name(vma); 336 if (!name) { 337 if (!mm) { 338 name = "[vdso]"; 339 goto done; 340 } 341 342 if (vma->vm_start <= mm->brk && 343 vma->vm_end >= mm->start_brk) { 344 name = "[heap]"; 345 goto done; 346 } 347 348 if (is_stack(vma)) 349 name = "[stack]"; 350 } 351 352 done: 353 if (name) { 354 seq_pad(m, ' '); 355 seq_puts(m, name); 356 } 357 seq_putc(m, '\n'); 358 } 359 360 static int show_map(struct seq_file *m, void *v, int is_pid) 361 { 362 show_map_vma(m, v, is_pid); 363 m_cache_vma(m, v); 364 return 0; 365 } 366 367 static int show_pid_map(struct seq_file *m, void *v) 368 { 369 return show_map(m, v, 1); 370 } 371 372 static int show_tid_map(struct seq_file *m, void *v) 373 { 374 return show_map(m, v, 0); 375 } 376 377 static const struct seq_operations proc_pid_maps_op = { 378 .start = m_start, 379 .next = m_next, 380 .stop = m_stop, 381 .show = show_pid_map 382 }; 383 384 static const struct seq_operations proc_tid_maps_op = { 385 .start = m_start, 386 .next = m_next, 387 .stop = m_stop, 388 .show = show_tid_map 389 }; 390 391 static int pid_maps_open(struct inode *inode, struct file *file) 392 { 393 return do_maps_open(inode, file, &proc_pid_maps_op); 394 } 395 396 static int tid_maps_open(struct inode *inode, struct file *file) 397 { 398 return do_maps_open(inode, file, &proc_tid_maps_op); 399 } 400 401 const struct file_operations proc_pid_maps_operations = { 402 .open = pid_maps_open, 403 .read = seq_read, 404 .llseek = seq_lseek, 405 .release = proc_map_release, 406 }; 407 408 const struct file_operations proc_tid_maps_operations = { 409 .open = tid_maps_open, 410 .read = seq_read, 411 .llseek = seq_lseek, 412 .release = proc_map_release, 413 }; 414 415 /* 416 * Proportional Set Size(PSS): my share of RSS. 417 * 418 * PSS of a process is the count of pages it has in memory, where each 419 * page is divided by the number of processes sharing it. So if a 420 * process has 1000 pages all to itself, and 1000 shared with one other 421 * process, its PSS will be 1500. 422 * 423 * To keep (accumulated) division errors low, we adopt a 64bit 424 * fixed-point pss counter to minimize division errors. So (pss >> 425 * PSS_SHIFT) would be the real byte count. 426 * 427 * A shift of 12 before division means (assuming 4K page size): 428 * - 1M 3-user-pages add up to 8KB errors; 429 * - supports mapcount up to 2^24, or 16M; 430 * - supports PSS up to 2^52 bytes, or 4PB. 431 */ 432 #define PSS_SHIFT 12 433 434 #ifdef CONFIG_PROC_PAGE_MONITOR 435 struct mem_size_stats { 436 bool first; 437 unsigned long resident; 438 unsigned long shared_clean; 439 unsigned long shared_dirty; 440 unsigned long private_clean; 441 unsigned long private_dirty; 442 unsigned long referenced; 443 unsigned long anonymous; 444 unsigned long lazyfree; 445 unsigned long anonymous_thp; 446 unsigned long shmem_thp; 447 unsigned long swap; 448 unsigned long shared_hugetlb; 449 unsigned long private_hugetlb; 450 unsigned long first_vma_start; 451 u64 pss; 452 u64 pss_locked; 453 u64 swap_pss; 454 bool check_shmem_swap; 455 }; 456 457 static void smaps_account(struct mem_size_stats *mss, struct page *page, 458 bool compound, bool young, bool dirty) 459 { 460 int i, nr = compound ? 1 << compound_order(page) : 1; 461 unsigned long size = nr * PAGE_SIZE; 462 463 if (PageAnon(page)) { 464 mss->anonymous += size; 465 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 466 mss->lazyfree += size; 467 } 468 469 mss->resident += size; 470 /* Accumulate the size in pages that have been accessed. */ 471 if (young || page_is_young(page) || PageReferenced(page)) 472 mss->referenced += size; 473 474 /* 475 * page_count(page) == 1 guarantees the page is mapped exactly once. 476 * If any subpage of the compound page mapped with PTE it would elevate 477 * page_count(). 478 */ 479 if (page_count(page) == 1) { 480 if (dirty || PageDirty(page)) 481 mss->private_dirty += size; 482 else 483 mss->private_clean += size; 484 mss->pss += (u64)size << PSS_SHIFT; 485 return; 486 } 487 488 for (i = 0; i < nr; i++, page++) { 489 int mapcount = page_mapcount(page); 490 491 if (mapcount >= 2) { 492 if (dirty || PageDirty(page)) 493 mss->shared_dirty += PAGE_SIZE; 494 else 495 mss->shared_clean += PAGE_SIZE; 496 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount; 497 } else { 498 if (dirty || PageDirty(page)) 499 mss->private_dirty += PAGE_SIZE; 500 else 501 mss->private_clean += PAGE_SIZE; 502 mss->pss += PAGE_SIZE << PSS_SHIFT; 503 } 504 } 505 } 506 507 #ifdef CONFIG_SHMEM 508 static int smaps_pte_hole(unsigned long addr, unsigned long end, 509 struct mm_walk *walk) 510 { 511 struct mem_size_stats *mss = walk->private; 512 513 mss->swap += shmem_partial_swap_usage( 514 walk->vma->vm_file->f_mapping, addr, end); 515 516 return 0; 517 } 518 #endif 519 520 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 521 struct mm_walk *walk) 522 { 523 struct mem_size_stats *mss = walk->private; 524 struct vm_area_struct *vma = walk->vma; 525 struct page *page = NULL; 526 527 if (pte_present(*pte)) { 528 page = vm_normal_page(vma, addr, *pte); 529 } else if (is_swap_pte(*pte)) { 530 swp_entry_t swpent = pte_to_swp_entry(*pte); 531 532 if (!non_swap_entry(swpent)) { 533 int mapcount; 534 535 mss->swap += PAGE_SIZE; 536 mapcount = swp_swapcount(swpent); 537 if (mapcount >= 2) { 538 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 539 540 do_div(pss_delta, mapcount); 541 mss->swap_pss += pss_delta; 542 } else { 543 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 544 } 545 } else if (is_migration_entry(swpent)) 546 page = migration_entry_to_page(swpent); 547 else if (is_device_private_entry(swpent)) 548 page = device_private_entry_to_page(swpent); 549 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 550 && pte_none(*pte))) { 551 page = find_get_entry(vma->vm_file->f_mapping, 552 linear_page_index(vma, addr)); 553 if (!page) 554 return; 555 556 if (radix_tree_exceptional_entry(page)) 557 mss->swap += PAGE_SIZE; 558 else 559 put_page(page); 560 561 return; 562 } 563 564 if (!page) 565 return; 566 567 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte)); 568 } 569 570 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 571 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 572 struct mm_walk *walk) 573 { 574 struct mem_size_stats *mss = walk->private; 575 struct vm_area_struct *vma = walk->vma; 576 struct page *page; 577 578 /* FOLL_DUMP will return -EFAULT on huge zero page */ 579 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 580 if (IS_ERR_OR_NULL(page)) 581 return; 582 if (PageAnon(page)) 583 mss->anonymous_thp += HPAGE_PMD_SIZE; 584 else if (PageSwapBacked(page)) 585 mss->shmem_thp += HPAGE_PMD_SIZE; 586 else if (is_zone_device_page(page)) 587 /* pass */; 588 else 589 VM_BUG_ON_PAGE(1, page); 590 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd)); 591 } 592 #else 593 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 594 struct mm_walk *walk) 595 { 596 } 597 #endif 598 599 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 600 struct mm_walk *walk) 601 { 602 struct vm_area_struct *vma = walk->vma; 603 pte_t *pte; 604 spinlock_t *ptl; 605 606 ptl = pmd_trans_huge_lock(pmd, vma); 607 if (ptl) { 608 if (pmd_present(*pmd)) 609 smaps_pmd_entry(pmd, addr, walk); 610 spin_unlock(ptl); 611 goto out; 612 } 613 614 if (pmd_trans_unstable(pmd)) 615 goto out; 616 /* 617 * The mmap_sem held all the way back in m_start() is what 618 * keeps khugepaged out of here and from collapsing things 619 * in here. 620 */ 621 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 622 for (; addr != end; pte++, addr += PAGE_SIZE) 623 smaps_pte_entry(pte, addr, walk); 624 pte_unmap_unlock(pte - 1, ptl); 625 out: 626 cond_resched(); 627 return 0; 628 } 629 630 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 631 { 632 /* 633 * Don't forget to update Documentation/ on changes. 634 */ 635 static const char mnemonics[BITS_PER_LONG][2] = { 636 /* 637 * In case if we meet a flag we don't know about. 638 */ 639 [0 ... (BITS_PER_LONG-1)] = "??", 640 641 [ilog2(VM_READ)] = "rd", 642 [ilog2(VM_WRITE)] = "wr", 643 [ilog2(VM_EXEC)] = "ex", 644 [ilog2(VM_SHARED)] = "sh", 645 [ilog2(VM_MAYREAD)] = "mr", 646 [ilog2(VM_MAYWRITE)] = "mw", 647 [ilog2(VM_MAYEXEC)] = "me", 648 [ilog2(VM_MAYSHARE)] = "ms", 649 [ilog2(VM_GROWSDOWN)] = "gd", 650 [ilog2(VM_PFNMAP)] = "pf", 651 [ilog2(VM_DENYWRITE)] = "dw", 652 #ifdef CONFIG_X86_INTEL_MPX 653 [ilog2(VM_MPX)] = "mp", 654 #endif 655 [ilog2(VM_LOCKED)] = "lo", 656 [ilog2(VM_IO)] = "io", 657 [ilog2(VM_SEQ_READ)] = "sr", 658 [ilog2(VM_RAND_READ)] = "rr", 659 [ilog2(VM_DONTCOPY)] = "dc", 660 [ilog2(VM_DONTEXPAND)] = "de", 661 [ilog2(VM_ACCOUNT)] = "ac", 662 [ilog2(VM_NORESERVE)] = "nr", 663 [ilog2(VM_HUGETLB)] = "ht", 664 [ilog2(VM_SYNC)] = "sf", 665 [ilog2(VM_ARCH_1)] = "ar", 666 [ilog2(VM_WIPEONFORK)] = "wf", 667 [ilog2(VM_DONTDUMP)] = "dd", 668 #ifdef CONFIG_MEM_SOFT_DIRTY 669 [ilog2(VM_SOFTDIRTY)] = "sd", 670 #endif 671 [ilog2(VM_MIXEDMAP)] = "mm", 672 [ilog2(VM_HUGEPAGE)] = "hg", 673 [ilog2(VM_NOHUGEPAGE)] = "nh", 674 [ilog2(VM_MERGEABLE)] = "mg", 675 [ilog2(VM_UFFD_MISSING)]= "um", 676 [ilog2(VM_UFFD_WP)] = "uw", 677 #ifdef CONFIG_ARCH_HAS_PKEYS 678 /* These come out via ProtectionKey: */ 679 [ilog2(VM_PKEY_BIT0)] = "", 680 [ilog2(VM_PKEY_BIT1)] = "", 681 [ilog2(VM_PKEY_BIT2)] = "", 682 [ilog2(VM_PKEY_BIT3)] = "", 683 #if VM_PKEY_BIT4 684 [ilog2(VM_PKEY_BIT4)] = "", 685 #endif 686 #endif /* CONFIG_ARCH_HAS_PKEYS */ 687 }; 688 size_t i; 689 690 seq_puts(m, "VmFlags: "); 691 for (i = 0; i < BITS_PER_LONG; i++) { 692 if (!mnemonics[i][0]) 693 continue; 694 if (vma->vm_flags & (1UL << i)) { 695 seq_putc(m, mnemonics[i][0]); 696 seq_putc(m, mnemonics[i][1]); 697 seq_putc(m, ' '); 698 } 699 } 700 seq_putc(m, '\n'); 701 } 702 703 #ifdef CONFIG_HUGETLB_PAGE 704 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 705 unsigned long addr, unsigned long end, 706 struct mm_walk *walk) 707 { 708 struct mem_size_stats *mss = walk->private; 709 struct vm_area_struct *vma = walk->vma; 710 struct page *page = NULL; 711 712 if (pte_present(*pte)) { 713 page = vm_normal_page(vma, addr, *pte); 714 } else if (is_swap_pte(*pte)) { 715 swp_entry_t swpent = pte_to_swp_entry(*pte); 716 717 if (is_migration_entry(swpent)) 718 page = migration_entry_to_page(swpent); 719 else if (is_device_private_entry(swpent)) 720 page = device_private_entry_to_page(swpent); 721 } 722 if (page) { 723 int mapcount = page_mapcount(page); 724 725 if (mapcount >= 2) 726 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 727 else 728 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 729 } 730 return 0; 731 } 732 #endif /* HUGETLB_PAGE */ 733 734 #define SEQ_PUT_DEC(str, val) \ 735 seq_put_decimal_ull_width(m, str, (val) >> 10, 8) 736 static int show_smap(struct seq_file *m, void *v, int is_pid) 737 { 738 struct proc_maps_private *priv = m->private; 739 struct vm_area_struct *vma = v; 740 struct mem_size_stats mss_stack; 741 struct mem_size_stats *mss; 742 struct mm_walk smaps_walk = { 743 .pmd_entry = smaps_pte_range, 744 #ifdef CONFIG_HUGETLB_PAGE 745 .hugetlb_entry = smaps_hugetlb_range, 746 #endif 747 .mm = vma->vm_mm, 748 }; 749 int ret = 0; 750 bool rollup_mode; 751 bool last_vma; 752 753 if (priv->rollup) { 754 rollup_mode = true; 755 mss = priv->rollup; 756 if (mss->first) { 757 mss->first_vma_start = vma->vm_start; 758 mss->first = false; 759 } 760 last_vma = !m_next_vma(priv, vma); 761 } else { 762 rollup_mode = false; 763 memset(&mss_stack, 0, sizeof(mss_stack)); 764 mss = &mss_stack; 765 } 766 767 smaps_walk.private = mss; 768 769 #ifdef CONFIG_SHMEM 770 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 771 /* 772 * For shared or readonly shmem mappings we know that all 773 * swapped out pages belong to the shmem object, and we can 774 * obtain the swap value much more efficiently. For private 775 * writable mappings, we might have COW pages that are 776 * not affected by the parent swapped out pages of the shmem 777 * object, so we have to distinguish them during the page walk. 778 * Unless we know that the shmem object (or the part mapped by 779 * our VMA) has no swapped out pages at all. 780 */ 781 unsigned long shmem_swapped = shmem_swap_usage(vma); 782 783 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 784 !(vma->vm_flags & VM_WRITE)) { 785 mss->swap = shmem_swapped; 786 } else { 787 mss->check_shmem_swap = true; 788 smaps_walk.pte_hole = smaps_pte_hole; 789 } 790 } 791 #endif 792 793 /* mmap_sem is held in m_start */ 794 walk_page_vma(vma, &smaps_walk); 795 if (vma->vm_flags & VM_LOCKED) 796 mss->pss_locked += mss->pss; 797 798 if (!rollup_mode) { 799 show_map_vma(m, vma, is_pid); 800 } else if (last_vma) { 801 show_vma_header_prefix( 802 m, mss->first_vma_start, vma->vm_end, 0, 0, 0, 0); 803 seq_pad(m, ' '); 804 seq_puts(m, "[rollup]\n"); 805 } else { 806 ret = SEQ_SKIP; 807 } 808 809 if (!rollup_mode) { 810 SEQ_PUT_DEC("Size: ", vma->vm_end - vma->vm_start); 811 SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma)); 812 SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); 813 seq_puts(m, " kB\n"); 814 } 815 816 if (!rollup_mode || last_vma) { 817 SEQ_PUT_DEC("Rss: ", mss->resident); 818 SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); 819 SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); 820 SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); 821 SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); 822 SEQ_PUT_DEC(" kB\nPrivate_Dirty: ", mss->private_dirty); 823 SEQ_PUT_DEC(" kB\nReferenced: ", mss->referenced); 824 SEQ_PUT_DEC(" kB\nAnonymous: ", mss->anonymous); 825 SEQ_PUT_DEC(" kB\nLazyFree: ", mss->lazyfree); 826 SEQ_PUT_DEC(" kB\nAnonHugePages: ", mss->anonymous_thp); 827 SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp); 828 SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb); 829 seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ", 830 mss->private_hugetlb >> 10, 7); 831 SEQ_PUT_DEC(" kB\nSwap: ", mss->swap); 832 SEQ_PUT_DEC(" kB\nSwapPss: ", 833 mss->swap_pss >> PSS_SHIFT); 834 SEQ_PUT_DEC(" kB\nLocked: ", 835 mss->pss_locked >> PSS_SHIFT); 836 seq_puts(m, " kB\n"); 837 } 838 if (!rollup_mode) { 839 if (arch_pkeys_enabled()) 840 seq_printf(m, "ProtectionKey: %8u\n", vma_pkey(vma)); 841 show_smap_vma_flags(m, vma); 842 } 843 m_cache_vma(m, vma); 844 return ret; 845 } 846 #undef SEQ_PUT_DEC 847 848 static int show_pid_smap(struct seq_file *m, void *v) 849 { 850 return show_smap(m, v, 1); 851 } 852 853 static int show_tid_smap(struct seq_file *m, void *v) 854 { 855 return show_smap(m, v, 0); 856 } 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_pid_smap 863 }; 864 865 static const struct seq_operations proc_tid_smaps_op = { 866 .start = m_start, 867 .next = m_next, 868 .stop = m_stop, 869 .show = show_tid_smap 870 }; 871 872 static int pid_smaps_open(struct inode *inode, struct file *file) 873 { 874 return do_maps_open(inode, file, &proc_pid_smaps_op); 875 } 876 877 static int pid_smaps_rollup_open(struct inode *inode, struct file *file) 878 { 879 struct seq_file *seq; 880 struct proc_maps_private *priv; 881 int ret = do_maps_open(inode, file, &proc_pid_smaps_op); 882 883 if (ret < 0) 884 return ret; 885 seq = file->private_data; 886 priv = seq->private; 887 priv->rollup = kzalloc(sizeof(*priv->rollup), GFP_KERNEL); 888 if (!priv->rollup) { 889 proc_map_release(inode, file); 890 return -ENOMEM; 891 } 892 priv->rollup->first = true; 893 return 0; 894 } 895 896 static int tid_smaps_open(struct inode *inode, struct file *file) 897 { 898 return do_maps_open(inode, file, &proc_tid_smaps_op); 899 } 900 901 const struct file_operations proc_pid_smaps_operations = { 902 .open = pid_smaps_open, 903 .read = seq_read, 904 .llseek = seq_lseek, 905 .release = proc_map_release, 906 }; 907 908 const struct file_operations proc_pid_smaps_rollup_operations = { 909 .open = pid_smaps_rollup_open, 910 .read = seq_read, 911 .llseek = seq_lseek, 912 .release = proc_map_release, 913 }; 914 915 const struct file_operations proc_tid_smaps_operations = { 916 .open = tid_smaps_open, 917 .read = seq_read, 918 .llseek = seq_lseek, 919 .release = proc_map_release, 920 }; 921 922 enum clear_refs_types { 923 CLEAR_REFS_ALL = 1, 924 CLEAR_REFS_ANON, 925 CLEAR_REFS_MAPPED, 926 CLEAR_REFS_SOFT_DIRTY, 927 CLEAR_REFS_MM_HIWATER_RSS, 928 CLEAR_REFS_LAST, 929 }; 930 931 struct clear_refs_private { 932 enum clear_refs_types type; 933 }; 934 935 #ifdef CONFIG_MEM_SOFT_DIRTY 936 static inline void clear_soft_dirty(struct vm_area_struct *vma, 937 unsigned long addr, pte_t *pte) 938 { 939 /* 940 * The soft-dirty tracker uses #PF-s to catch writes 941 * to pages, so write-protect the pte as well. See the 942 * Documentation/admin-guide/mm/soft-dirty.rst for full description 943 * of how soft-dirty works. 944 */ 945 pte_t ptent = *pte; 946 947 if (pte_present(ptent)) { 948 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte); 949 ptent = pte_wrprotect(ptent); 950 ptent = pte_clear_soft_dirty(ptent); 951 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent); 952 } else if (is_swap_pte(ptent)) { 953 ptent = pte_swp_clear_soft_dirty(ptent); 954 set_pte_at(vma->vm_mm, addr, pte, ptent); 955 } 956 } 957 #else 958 static inline void clear_soft_dirty(struct vm_area_struct *vma, 959 unsigned long addr, pte_t *pte) 960 { 961 } 962 #endif 963 964 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 965 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 966 unsigned long addr, pmd_t *pmdp) 967 { 968 pmd_t old, pmd = *pmdp; 969 970 if (pmd_present(pmd)) { 971 /* See comment in change_huge_pmd() */ 972 old = pmdp_invalidate(vma, addr, pmdp); 973 if (pmd_dirty(old)) 974 pmd = pmd_mkdirty(pmd); 975 if (pmd_young(old)) 976 pmd = pmd_mkyoung(pmd); 977 978 pmd = pmd_wrprotect(pmd); 979 pmd = pmd_clear_soft_dirty(pmd); 980 981 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 982 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 983 pmd = pmd_swp_clear_soft_dirty(pmd); 984 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 985 } 986 } 987 #else 988 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 989 unsigned long addr, pmd_t *pmdp) 990 { 991 } 992 #endif 993 994 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 995 unsigned long end, struct mm_walk *walk) 996 { 997 struct clear_refs_private *cp = walk->private; 998 struct vm_area_struct *vma = walk->vma; 999 pte_t *pte, ptent; 1000 spinlock_t *ptl; 1001 struct page *page; 1002 1003 ptl = pmd_trans_huge_lock(pmd, vma); 1004 if (ptl) { 1005 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1006 clear_soft_dirty_pmd(vma, addr, pmd); 1007 goto out; 1008 } 1009 1010 if (!pmd_present(*pmd)) 1011 goto out; 1012 1013 page = pmd_page(*pmd); 1014 1015 /* Clear accessed and referenced bits. */ 1016 pmdp_test_and_clear_young(vma, addr, pmd); 1017 test_and_clear_page_young(page); 1018 ClearPageReferenced(page); 1019 out: 1020 spin_unlock(ptl); 1021 return 0; 1022 } 1023 1024 if (pmd_trans_unstable(pmd)) 1025 return 0; 1026 1027 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1028 for (; addr != end; pte++, addr += PAGE_SIZE) { 1029 ptent = *pte; 1030 1031 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1032 clear_soft_dirty(vma, addr, pte); 1033 continue; 1034 } 1035 1036 if (!pte_present(ptent)) 1037 continue; 1038 1039 page = vm_normal_page(vma, addr, ptent); 1040 if (!page) 1041 continue; 1042 1043 /* Clear accessed and referenced bits. */ 1044 ptep_test_and_clear_young(vma, addr, pte); 1045 test_and_clear_page_young(page); 1046 ClearPageReferenced(page); 1047 } 1048 pte_unmap_unlock(pte - 1, ptl); 1049 cond_resched(); 1050 return 0; 1051 } 1052 1053 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1054 struct mm_walk *walk) 1055 { 1056 struct clear_refs_private *cp = walk->private; 1057 struct vm_area_struct *vma = walk->vma; 1058 1059 if (vma->vm_flags & VM_PFNMAP) 1060 return 1; 1061 1062 /* 1063 * Writing 1 to /proc/pid/clear_refs affects all pages. 1064 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1065 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1066 * Writing 4 to /proc/pid/clear_refs affects all pages. 1067 */ 1068 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1069 return 1; 1070 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1071 return 1; 1072 return 0; 1073 } 1074 1075 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1076 size_t count, loff_t *ppos) 1077 { 1078 struct task_struct *task; 1079 char buffer[PROC_NUMBUF]; 1080 struct mm_struct *mm; 1081 struct vm_area_struct *vma; 1082 enum clear_refs_types type; 1083 struct mmu_gather tlb; 1084 int itype; 1085 int rv; 1086 1087 memset(buffer, 0, sizeof(buffer)); 1088 if (count > sizeof(buffer) - 1) 1089 count = sizeof(buffer) - 1; 1090 if (copy_from_user(buffer, buf, count)) 1091 return -EFAULT; 1092 rv = kstrtoint(strstrip(buffer), 10, &itype); 1093 if (rv < 0) 1094 return rv; 1095 type = (enum clear_refs_types)itype; 1096 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1097 return -EINVAL; 1098 1099 task = get_proc_task(file_inode(file)); 1100 if (!task) 1101 return -ESRCH; 1102 mm = get_task_mm(task); 1103 if (mm) { 1104 struct clear_refs_private cp = { 1105 .type = type, 1106 }; 1107 struct mm_walk clear_refs_walk = { 1108 .pmd_entry = clear_refs_pte_range, 1109 .test_walk = clear_refs_test_walk, 1110 .mm = mm, 1111 .private = &cp, 1112 }; 1113 1114 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1115 if (down_write_killable(&mm->mmap_sem)) { 1116 count = -EINTR; 1117 goto out_mm; 1118 } 1119 1120 /* 1121 * Writing 5 to /proc/pid/clear_refs resets the peak 1122 * resident set size to this mm's current rss value. 1123 */ 1124 reset_mm_hiwater_rss(mm); 1125 up_write(&mm->mmap_sem); 1126 goto out_mm; 1127 } 1128 1129 down_read(&mm->mmap_sem); 1130 tlb_gather_mmu(&tlb, mm, 0, -1); 1131 if (type == CLEAR_REFS_SOFT_DIRTY) { 1132 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1133 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1134 continue; 1135 up_read(&mm->mmap_sem); 1136 if (down_write_killable(&mm->mmap_sem)) { 1137 count = -EINTR; 1138 goto out_mm; 1139 } 1140 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1141 vma->vm_flags &= ~VM_SOFTDIRTY; 1142 vma_set_page_prot(vma); 1143 } 1144 downgrade_write(&mm->mmap_sem); 1145 break; 1146 } 1147 mmu_notifier_invalidate_range_start(mm, 0, -1); 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(mm, 0, -1); 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, int is_pid) 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 int show_pid_numa_map(struct seq_file *m, void *v) 1816 { 1817 return show_numa_map(m, v, 1); 1818 } 1819 1820 static int show_tid_numa_map(struct seq_file *m, void *v) 1821 { 1822 return show_numa_map(m, v, 0); 1823 } 1824 1825 static const struct seq_operations proc_pid_numa_maps_op = { 1826 .start = m_start, 1827 .next = m_next, 1828 .stop = m_stop, 1829 .show = show_pid_numa_map, 1830 }; 1831 1832 static const struct seq_operations proc_tid_numa_maps_op = { 1833 .start = m_start, 1834 .next = m_next, 1835 .stop = m_stop, 1836 .show = show_tid_numa_map, 1837 }; 1838 1839 static int numa_maps_open(struct inode *inode, struct file *file, 1840 const struct seq_operations *ops) 1841 { 1842 return proc_maps_open(inode, file, ops, 1843 sizeof(struct numa_maps_private)); 1844 } 1845 1846 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1847 { 1848 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1849 } 1850 1851 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1852 { 1853 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1854 } 1855 1856 const struct file_operations proc_pid_numa_maps_operations = { 1857 .open = pid_numa_maps_open, 1858 .read = seq_read, 1859 .llseek = seq_lseek, 1860 .release = proc_map_release, 1861 }; 1862 1863 const struct file_operations proc_tid_numa_maps_operations = { 1864 .open = tid_numa_maps_open, 1865 .read = seq_read, 1866 .llseek = seq_lseek, 1867 .release = proc_map_release, 1868 }; 1869 #endif /* CONFIG_NUMA */ 1870