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 22 #include <asm/elf.h> 23 #include <asm/tlb.h> 24 #include <asm/tlbflush.h> 25 #include "internal.h" 26 27 #define SEQ_PUT_DEC(str, val) \ 28 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8) 29 void task_mem(struct seq_file *m, struct mm_struct *mm) 30 { 31 unsigned long text, lib, swap, anon, file, shmem; 32 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 33 34 anon = get_mm_counter(mm, MM_ANONPAGES); 35 file = get_mm_counter(mm, MM_FILEPAGES); 36 shmem = get_mm_counter(mm, MM_SHMEMPAGES); 37 38 /* 39 * Note: to minimize their overhead, mm maintains hiwater_vm and 40 * hiwater_rss only when about to *lower* total_vm or rss. Any 41 * collector of these hiwater stats must therefore get total_vm 42 * and rss too, which will usually be the higher. Barriers? not 43 * worth the effort, such snapshots can always be inconsistent. 44 */ 45 hiwater_vm = total_vm = mm->total_vm; 46 if (hiwater_vm < mm->hiwater_vm) 47 hiwater_vm = mm->hiwater_vm; 48 hiwater_rss = total_rss = anon + file + shmem; 49 if (hiwater_rss < mm->hiwater_rss) 50 hiwater_rss = mm->hiwater_rss; 51 52 /* split executable areas between text and lib */ 53 text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK); 54 text = min(text, mm->exec_vm << PAGE_SHIFT); 55 lib = (mm->exec_vm << PAGE_SHIFT) - text; 56 57 swap = get_mm_counter(mm, MM_SWAPENTS); 58 SEQ_PUT_DEC("VmPeak:\t", hiwater_vm); 59 SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm); 60 SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm); 61 SEQ_PUT_DEC(" kB\nVmPin:\t", mm->pinned_vm); 62 SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss); 63 SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss); 64 SEQ_PUT_DEC(" kB\nRssAnon:\t", anon); 65 SEQ_PUT_DEC(" kB\nRssFile:\t", file); 66 SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem); 67 SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm); 68 SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm); 69 seq_put_decimal_ull_width(m, 70 " kB\nVmExe:\t", text >> 10, 8); 71 seq_put_decimal_ull_width(m, 72 " kB\nVmLib:\t", lib >> 10, 8); 73 seq_put_decimal_ull_width(m, 74 " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8); 75 SEQ_PUT_DEC(" kB\nVmSwap:\t", swap); 76 seq_puts(m, " kB\n"); 77 hugetlb_report_usage(m, mm); 78 } 79 #undef SEQ_PUT_DEC 80 81 unsigned long task_vsize(struct mm_struct *mm) 82 { 83 return PAGE_SIZE * mm->total_vm; 84 } 85 86 unsigned long task_statm(struct mm_struct *mm, 87 unsigned long *shared, unsigned long *text, 88 unsigned long *data, unsigned long *resident) 89 { 90 *shared = get_mm_counter(mm, MM_FILEPAGES) + 91 get_mm_counter(mm, MM_SHMEMPAGES); 92 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 93 >> PAGE_SHIFT; 94 *data = mm->data_vm + mm->stack_vm; 95 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 96 return mm->total_vm; 97 } 98 99 #ifdef CONFIG_NUMA 100 /* 101 * Save get_task_policy() for show_numa_map(). 102 */ 103 static void hold_task_mempolicy(struct proc_maps_private *priv) 104 { 105 struct task_struct *task = priv->task; 106 107 task_lock(task); 108 priv->task_mempolicy = get_task_policy(task); 109 mpol_get(priv->task_mempolicy); 110 task_unlock(task); 111 } 112 static void release_task_mempolicy(struct proc_maps_private *priv) 113 { 114 mpol_put(priv->task_mempolicy); 115 } 116 #else 117 static void hold_task_mempolicy(struct proc_maps_private *priv) 118 { 119 } 120 static void release_task_mempolicy(struct proc_maps_private *priv) 121 { 122 } 123 #endif 124 125 static void vma_stop(struct proc_maps_private *priv) 126 { 127 struct mm_struct *mm = priv->mm; 128 129 release_task_mempolicy(priv); 130 up_read(&mm->mmap_sem); 131 mmput(mm); 132 } 133 134 static struct vm_area_struct * 135 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma) 136 { 137 if (vma == priv->tail_vma) 138 return NULL; 139 return vma->vm_next ?: priv->tail_vma; 140 } 141 142 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma) 143 { 144 if (m->count < m->size) /* vma is copied successfully */ 145 m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL; 146 } 147 148 static void *m_start(struct seq_file *m, loff_t *ppos) 149 { 150 struct proc_maps_private *priv = m->private; 151 unsigned long last_addr = m->version; 152 struct mm_struct *mm; 153 struct vm_area_struct *vma; 154 unsigned int pos = *ppos; 155 156 /* See m_cache_vma(). Zero at the start or after lseek. */ 157 if (last_addr == -1UL) 158 return NULL; 159 160 priv->task = get_proc_task(priv->inode); 161 if (!priv->task) 162 return ERR_PTR(-ESRCH); 163 164 mm = priv->mm; 165 if (!mm || !mmget_not_zero(mm)) 166 return NULL; 167 168 down_read(&mm->mmap_sem); 169 hold_task_mempolicy(priv); 170 priv->tail_vma = get_gate_vma(mm); 171 172 if (last_addr) { 173 vma = find_vma(mm, last_addr - 1); 174 if (vma && vma->vm_start <= last_addr) 175 vma = m_next_vma(priv, vma); 176 if (vma) 177 return vma; 178 } 179 180 m->version = 0; 181 if (pos < mm->map_count) { 182 for (vma = mm->mmap; pos; pos--) { 183 m->version = vma->vm_start; 184 vma = vma->vm_next; 185 } 186 return vma; 187 } 188 189 /* we do not bother to update m->version in this case */ 190 if (pos == mm->map_count && priv->tail_vma) 191 return priv->tail_vma; 192 193 vma_stop(priv); 194 return NULL; 195 } 196 197 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 198 { 199 struct proc_maps_private *priv = m->private; 200 struct vm_area_struct *next; 201 202 (*pos)++; 203 next = m_next_vma(priv, v); 204 if (!next) 205 vma_stop(priv); 206 return next; 207 } 208 209 static void m_stop(struct seq_file *m, void *v) 210 { 211 struct proc_maps_private *priv = m->private; 212 213 if (!IS_ERR_OR_NULL(v)) 214 vma_stop(priv); 215 if (priv->task) { 216 put_task_struct(priv->task); 217 priv->task = NULL; 218 } 219 } 220 221 static int proc_maps_open(struct inode *inode, struct file *file, 222 const struct seq_operations *ops, int psize) 223 { 224 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 225 226 if (!priv) 227 return -ENOMEM; 228 229 priv->inode = inode; 230 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 231 if (IS_ERR(priv->mm)) { 232 int err = PTR_ERR(priv->mm); 233 234 seq_release_private(inode, file); 235 return err; 236 } 237 238 return 0; 239 } 240 241 static int proc_map_release(struct inode *inode, struct file *file) 242 { 243 struct seq_file *seq = file->private_data; 244 struct proc_maps_private *priv = seq->private; 245 246 if (priv->mm) 247 mmdrop(priv->mm); 248 249 kfree(priv->rollup); 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, int is_pid) 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, int is_pid) 360 { 361 show_map_vma(m, v, is_pid); 362 m_cache_vma(m, v); 363 return 0; 364 } 365 366 static int show_pid_map(struct seq_file *m, void *v) 367 { 368 return show_map(m, v, 1); 369 } 370 371 static int show_tid_map(struct seq_file *m, void *v) 372 { 373 return show_map(m, v, 0); 374 } 375 376 static const struct seq_operations proc_pid_maps_op = { 377 .start = m_start, 378 .next = m_next, 379 .stop = m_stop, 380 .show = show_pid_map 381 }; 382 383 static const struct seq_operations proc_tid_maps_op = { 384 .start = m_start, 385 .next = m_next, 386 .stop = m_stop, 387 .show = show_tid_map 388 }; 389 390 static int pid_maps_open(struct inode *inode, struct file *file) 391 { 392 return do_maps_open(inode, file, &proc_pid_maps_op); 393 } 394 395 static int tid_maps_open(struct inode *inode, struct file *file) 396 { 397 return do_maps_open(inode, file, &proc_tid_maps_op); 398 } 399 400 const struct file_operations proc_pid_maps_operations = { 401 .open = pid_maps_open, 402 .read = seq_read, 403 .llseek = seq_lseek, 404 .release = proc_map_release, 405 }; 406 407 const struct file_operations proc_tid_maps_operations = { 408 .open = tid_maps_open, 409 .read = seq_read, 410 .llseek = seq_lseek, 411 .release = proc_map_release, 412 }; 413 414 /* 415 * Proportional Set Size(PSS): my share of RSS. 416 * 417 * PSS of a process is the count of pages it has in memory, where each 418 * page is divided by the number of processes sharing it. So if a 419 * process has 1000 pages all to itself, and 1000 shared with one other 420 * process, its PSS will be 1500. 421 * 422 * To keep (accumulated) division errors low, we adopt a 64bit 423 * fixed-point pss counter to minimize division errors. So (pss >> 424 * PSS_SHIFT) would be the real byte count. 425 * 426 * A shift of 12 before division means (assuming 4K page size): 427 * - 1M 3-user-pages add up to 8KB errors; 428 * - supports mapcount up to 2^24, or 16M; 429 * - supports PSS up to 2^52 bytes, or 4PB. 430 */ 431 #define PSS_SHIFT 12 432 433 #ifdef CONFIG_PROC_PAGE_MONITOR 434 struct mem_size_stats { 435 bool first; 436 unsigned long resident; 437 unsigned long shared_clean; 438 unsigned long shared_dirty; 439 unsigned long private_clean; 440 unsigned long private_dirty; 441 unsigned long referenced; 442 unsigned long anonymous; 443 unsigned long lazyfree; 444 unsigned long anonymous_thp; 445 unsigned long shmem_thp; 446 unsigned long swap; 447 unsigned long shared_hugetlb; 448 unsigned long private_hugetlb; 449 unsigned long first_vma_start; 450 u64 pss; 451 u64 pss_locked; 452 u64 swap_pss; 453 bool check_shmem_swap; 454 }; 455 456 static void smaps_account(struct mem_size_stats *mss, struct page *page, 457 bool compound, bool young, bool dirty) 458 { 459 int i, nr = compound ? 1 << compound_order(page) : 1; 460 unsigned long size = nr * PAGE_SIZE; 461 462 if (PageAnon(page)) { 463 mss->anonymous += size; 464 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 465 mss->lazyfree += size; 466 } 467 468 mss->resident += size; 469 /* Accumulate the size in pages that have been accessed. */ 470 if (young || page_is_young(page) || PageReferenced(page)) 471 mss->referenced += size; 472 473 /* 474 * page_count(page) == 1 guarantees the page is mapped exactly once. 475 * If any subpage of the compound page mapped with PTE it would elevate 476 * page_count(). 477 */ 478 if (page_count(page) == 1) { 479 if (dirty || PageDirty(page)) 480 mss->private_dirty += size; 481 else 482 mss->private_clean += size; 483 mss->pss += (u64)size << PSS_SHIFT; 484 return; 485 } 486 487 for (i = 0; i < nr; i++, page++) { 488 int mapcount = page_mapcount(page); 489 490 if (mapcount >= 2) { 491 if (dirty || PageDirty(page)) 492 mss->shared_dirty += PAGE_SIZE; 493 else 494 mss->shared_clean += PAGE_SIZE; 495 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount; 496 } else { 497 if (dirty || PageDirty(page)) 498 mss->private_dirty += PAGE_SIZE; 499 else 500 mss->private_clean += PAGE_SIZE; 501 mss->pss += PAGE_SIZE << PSS_SHIFT; 502 } 503 } 504 } 505 506 #ifdef CONFIG_SHMEM 507 static int smaps_pte_hole(unsigned long addr, unsigned long end, 508 struct mm_walk *walk) 509 { 510 struct mem_size_stats *mss = walk->private; 511 512 mss->swap += shmem_partial_swap_usage( 513 walk->vma->vm_file->f_mapping, addr, end); 514 515 return 0; 516 } 517 #endif 518 519 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 520 struct mm_walk *walk) 521 { 522 struct mem_size_stats *mss = walk->private; 523 struct vm_area_struct *vma = walk->vma; 524 struct page *page = NULL; 525 526 if (pte_present(*pte)) { 527 page = vm_normal_page(vma, addr, *pte); 528 } else if (is_swap_pte(*pte)) { 529 swp_entry_t swpent = pte_to_swp_entry(*pte); 530 531 if (!non_swap_entry(swpent)) { 532 int mapcount; 533 534 mss->swap += PAGE_SIZE; 535 mapcount = swp_swapcount(swpent); 536 if (mapcount >= 2) { 537 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 538 539 do_div(pss_delta, mapcount); 540 mss->swap_pss += pss_delta; 541 } else { 542 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 543 } 544 } else if (is_migration_entry(swpent)) 545 page = migration_entry_to_page(swpent); 546 else if (is_device_private_entry(swpent)) 547 page = device_private_entry_to_page(swpent); 548 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 549 && pte_none(*pte))) { 550 page = find_get_entry(vma->vm_file->f_mapping, 551 linear_page_index(vma, addr)); 552 if (!page) 553 return; 554 555 if (radix_tree_exceptional_entry(page)) 556 mss->swap += PAGE_SIZE; 557 else 558 put_page(page); 559 560 return; 561 } 562 563 if (!page) 564 return; 565 566 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte)); 567 } 568 569 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 570 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 571 struct mm_walk *walk) 572 { 573 struct mem_size_stats *mss = walk->private; 574 struct vm_area_struct *vma = walk->vma; 575 struct page *page; 576 577 /* FOLL_DUMP will return -EFAULT on huge zero page */ 578 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 579 if (IS_ERR_OR_NULL(page)) 580 return; 581 if (PageAnon(page)) 582 mss->anonymous_thp += HPAGE_PMD_SIZE; 583 else if (PageSwapBacked(page)) 584 mss->shmem_thp += HPAGE_PMD_SIZE; 585 else if (is_zone_device_page(page)) 586 /* pass */; 587 else 588 VM_BUG_ON_PAGE(1, page); 589 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd)); 590 } 591 #else 592 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 593 struct mm_walk *walk) 594 { 595 } 596 #endif 597 598 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 599 struct mm_walk *walk) 600 { 601 struct vm_area_struct *vma = walk->vma; 602 pte_t *pte; 603 spinlock_t *ptl; 604 605 ptl = pmd_trans_huge_lock(pmd, vma); 606 if (ptl) { 607 if (pmd_present(*pmd)) 608 smaps_pmd_entry(pmd, addr, walk); 609 spin_unlock(ptl); 610 goto out; 611 } 612 613 if (pmd_trans_unstable(pmd)) 614 goto out; 615 /* 616 * The mmap_sem held all the way back in m_start() is what 617 * keeps khugepaged out of here and from collapsing things 618 * in here. 619 */ 620 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 621 for (; addr != end; pte++, addr += PAGE_SIZE) 622 smaps_pte_entry(pte, addr, walk); 623 pte_unmap_unlock(pte - 1, ptl); 624 out: 625 cond_resched(); 626 return 0; 627 } 628 629 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 630 { 631 /* 632 * Don't forget to update Documentation/ on changes. 633 */ 634 static const char mnemonics[BITS_PER_LONG][2] = { 635 /* 636 * In case if we meet a flag we don't know about. 637 */ 638 [0 ... (BITS_PER_LONG-1)] = "??", 639 640 [ilog2(VM_READ)] = "rd", 641 [ilog2(VM_WRITE)] = "wr", 642 [ilog2(VM_EXEC)] = "ex", 643 [ilog2(VM_SHARED)] = "sh", 644 [ilog2(VM_MAYREAD)] = "mr", 645 [ilog2(VM_MAYWRITE)] = "mw", 646 [ilog2(VM_MAYEXEC)] = "me", 647 [ilog2(VM_MAYSHARE)] = "ms", 648 [ilog2(VM_GROWSDOWN)] = "gd", 649 [ilog2(VM_PFNMAP)] = "pf", 650 [ilog2(VM_DENYWRITE)] = "dw", 651 #ifdef CONFIG_X86_INTEL_MPX 652 [ilog2(VM_MPX)] = "mp", 653 #endif 654 [ilog2(VM_LOCKED)] = "lo", 655 [ilog2(VM_IO)] = "io", 656 [ilog2(VM_SEQ_READ)] = "sr", 657 [ilog2(VM_RAND_READ)] = "rr", 658 [ilog2(VM_DONTCOPY)] = "dc", 659 [ilog2(VM_DONTEXPAND)] = "de", 660 [ilog2(VM_ACCOUNT)] = "ac", 661 [ilog2(VM_NORESERVE)] = "nr", 662 [ilog2(VM_HUGETLB)] = "ht", 663 [ilog2(VM_SYNC)] = "sf", 664 [ilog2(VM_ARCH_1)] = "ar", 665 [ilog2(VM_WIPEONFORK)] = "wf", 666 [ilog2(VM_DONTDUMP)] = "dd", 667 #ifdef CONFIG_MEM_SOFT_DIRTY 668 [ilog2(VM_SOFTDIRTY)] = "sd", 669 #endif 670 [ilog2(VM_MIXEDMAP)] = "mm", 671 [ilog2(VM_HUGEPAGE)] = "hg", 672 [ilog2(VM_NOHUGEPAGE)] = "nh", 673 [ilog2(VM_MERGEABLE)] = "mg", 674 [ilog2(VM_UFFD_MISSING)]= "um", 675 [ilog2(VM_UFFD_WP)] = "uw", 676 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS 677 /* These come out via ProtectionKey: */ 678 [ilog2(VM_PKEY_BIT0)] = "", 679 [ilog2(VM_PKEY_BIT1)] = "", 680 [ilog2(VM_PKEY_BIT2)] = "", 681 [ilog2(VM_PKEY_BIT3)] = "", 682 #endif 683 }; 684 size_t i; 685 686 seq_puts(m, "VmFlags: "); 687 for (i = 0; i < BITS_PER_LONG; i++) { 688 if (!mnemonics[i][0]) 689 continue; 690 if (vma->vm_flags & (1UL << i)) { 691 seq_putc(m, mnemonics[i][0]); 692 seq_putc(m, mnemonics[i][1]); 693 seq_putc(m, ' '); 694 } 695 } 696 seq_putc(m, '\n'); 697 } 698 699 #ifdef CONFIG_HUGETLB_PAGE 700 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 701 unsigned long addr, unsigned long end, 702 struct mm_walk *walk) 703 { 704 struct mem_size_stats *mss = walk->private; 705 struct vm_area_struct *vma = walk->vma; 706 struct page *page = NULL; 707 708 if (pte_present(*pte)) { 709 page = vm_normal_page(vma, addr, *pte); 710 } else if (is_swap_pte(*pte)) { 711 swp_entry_t swpent = pte_to_swp_entry(*pte); 712 713 if (is_migration_entry(swpent)) 714 page = migration_entry_to_page(swpent); 715 else if (is_device_private_entry(swpent)) 716 page = device_private_entry_to_page(swpent); 717 } 718 if (page) { 719 int mapcount = page_mapcount(page); 720 721 if (mapcount >= 2) 722 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 723 else 724 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 725 } 726 return 0; 727 } 728 #endif /* HUGETLB_PAGE */ 729 730 void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma) 731 { 732 } 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: ", mss->pss >> PSS_SHIFT); 835 seq_puts(m, " kB\n"); 836 } 837 if (!rollup_mode) { 838 arch_show_smap(m, vma); 839 show_smap_vma_flags(m, vma); 840 } 841 m_cache_vma(m, vma); 842 return ret; 843 } 844 #undef SEQ_PUT_DEC 845 846 static int show_pid_smap(struct seq_file *m, void *v) 847 { 848 return show_smap(m, v, 1); 849 } 850 851 static int show_tid_smap(struct seq_file *m, void *v) 852 { 853 return show_smap(m, v, 0); 854 } 855 856 static const struct seq_operations proc_pid_smaps_op = { 857 .start = m_start, 858 .next = m_next, 859 .stop = m_stop, 860 .show = show_pid_smap 861 }; 862 863 static const struct seq_operations proc_tid_smaps_op = { 864 .start = m_start, 865 .next = m_next, 866 .stop = m_stop, 867 .show = show_tid_smap 868 }; 869 870 static int pid_smaps_open(struct inode *inode, struct file *file) 871 { 872 return do_maps_open(inode, file, &proc_pid_smaps_op); 873 } 874 875 static int pid_smaps_rollup_open(struct inode *inode, struct file *file) 876 { 877 struct seq_file *seq; 878 struct proc_maps_private *priv; 879 int ret = do_maps_open(inode, file, &proc_pid_smaps_op); 880 881 if (ret < 0) 882 return ret; 883 seq = file->private_data; 884 priv = seq->private; 885 priv->rollup = kzalloc(sizeof(*priv->rollup), GFP_KERNEL); 886 if (!priv->rollup) { 887 proc_map_release(inode, file); 888 return -ENOMEM; 889 } 890 priv->rollup->first = true; 891 return 0; 892 } 893 894 static int tid_smaps_open(struct inode *inode, struct file *file) 895 { 896 return do_maps_open(inode, file, &proc_tid_smaps_op); 897 } 898 899 const struct file_operations proc_pid_smaps_operations = { 900 .open = pid_smaps_open, 901 .read = seq_read, 902 .llseek = seq_lseek, 903 .release = proc_map_release, 904 }; 905 906 const struct file_operations proc_pid_smaps_rollup_operations = { 907 .open = pid_smaps_rollup_open, 908 .read = seq_read, 909 .llseek = seq_lseek, 910 .release = proc_map_release, 911 }; 912 913 const struct file_operations proc_tid_smaps_operations = { 914 .open = tid_smaps_open, 915 .read = seq_read, 916 .llseek = seq_lseek, 917 .release = proc_map_release, 918 }; 919 920 enum clear_refs_types { 921 CLEAR_REFS_ALL = 1, 922 CLEAR_REFS_ANON, 923 CLEAR_REFS_MAPPED, 924 CLEAR_REFS_SOFT_DIRTY, 925 CLEAR_REFS_MM_HIWATER_RSS, 926 CLEAR_REFS_LAST, 927 }; 928 929 struct clear_refs_private { 930 enum clear_refs_types type; 931 }; 932 933 #ifdef CONFIG_MEM_SOFT_DIRTY 934 static inline void clear_soft_dirty(struct vm_area_struct *vma, 935 unsigned long addr, pte_t *pte) 936 { 937 /* 938 * The soft-dirty tracker uses #PF-s to catch writes 939 * to pages, so write-protect the pte as well. See the 940 * Documentation/vm/soft-dirty.rst for full description 941 * of how soft-dirty works. 942 */ 943 pte_t ptent = *pte; 944 945 if (pte_present(ptent)) { 946 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte); 947 ptent = pte_wrprotect(ptent); 948 ptent = pte_clear_soft_dirty(ptent); 949 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent); 950 } else if (is_swap_pte(ptent)) { 951 ptent = pte_swp_clear_soft_dirty(ptent); 952 set_pte_at(vma->vm_mm, addr, pte, ptent); 953 } 954 } 955 #else 956 static inline void clear_soft_dirty(struct vm_area_struct *vma, 957 unsigned long addr, pte_t *pte) 958 { 959 } 960 #endif 961 962 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 963 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 964 unsigned long addr, pmd_t *pmdp) 965 { 966 pmd_t old, pmd = *pmdp; 967 968 if (pmd_present(pmd)) { 969 /* See comment in change_huge_pmd() */ 970 old = pmdp_invalidate(vma, addr, pmdp); 971 if (pmd_dirty(old)) 972 pmd = pmd_mkdirty(pmd); 973 if (pmd_young(old)) 974 pmd = pmd_mkyoung(pmd); 975 976 pmd = pmd_wrprotect(pmd); 977 pmd = pmd_clear_soft_dirty(pmd); 978 979 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 980 } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { 981 pmd = pmd_swp_clear_soft_dirty(pmd); 982 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 983 } 984 } 985 #else 986 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 987 unsigned long addr, pmd_t *pmdp) 988 { 989 } 990 #endif 991 992 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 993 unsigned long end, struct mm_walk *walk) 994 { 995 struct clear_refs_private *cp = walk->private; 996 struct vm_area_struct *vma = walk->vma; 997 pte_t *pte, ptent; 998 spinlock_t *ptl; 999 struct page *page; 1000 1001 ptl = pmd_trans_huge_lock(pmd, vma); 1002 if (ptl) { 1003 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1004 clear_soft_dirty_pmd(vma, addr, pmd); 1005 goto out; 1006 } 1007 1008 if (!pmd_present(*pmd)) 1009 goto out; 1010 1011 page = pmd_page(*pmd); 1012 1013 /* Clear accessed and referenced bits. */ 1014 pmdp_test_and_clear_young(vma, addr, pmd); 1015 test_and_clear_page_young(page); 1016 ClearPageReferenced(page); 1017 out: 1018 spin_unlock(ptl); 1019 return 0; 1020 } 1021 1022 if (pmd_trans_unstable(pmd)) 1023 return 0; 1024 1025 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1026 for (; addr != end; pte++, addr += PAGE_SIZE) { 1027 ptent = *pte; 1028 1029 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 1030 clear_soft_dirty(vma, addr, pte); 1031 continue; 1032 } 1033 1034 if (!pte_present(ptent)) 1035 continue; 1036 1037 page = vm_normal_page(vma, addr, ptent); 1038 if (!page) 1039 continue; 1040 1041 /* Clear accessed and referenced bits. */ 1042 ptep_test_and_clear_young(vma, addr, pte); 1043 test_and_clear_page_young(page); 1044 ClearPageReferenced(page); 1045 } 1046 pte_unmap_unlock(pte - 1, ptl); 1047 cond_resched(); 1048 return 0; 1049 } 1050 1051 static int clear_refs_test_walk(unsigned long start, unsigned long end, 1052 struct mm_walk *walk) 1053 { 1054 struct clear_refs_private *cp = walk->private; 1055 struct vm_area_struct *vma = walk->vma; 1056 1057 if (vma->vm_flags & VM_PFNMAP) 1058 return 1; 1059 1060 /* 1061 * Writing 1 to /proc/pid/clear_refs affects all pages. 1062 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 1063 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 1064 * Writing 4 to /proc/pid/clear_refs affects all pages. 1065 */ 1066 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1067 return 1; 1068 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1069 return 1; 1070 return 0; 1071 } 1072 1073 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1074 size_t count, loff_t *ppos) 1075 { 1076 struct task_struct *task; 1077 char buffer[PROC_NUMBUF]; 1078 struct mm_struct *mm; 1079 struct vm_area_struct *vma; 1080 enum clear_refs_types type; 1081 struct mmu_gather tlb; 1082 int itype; 1083 int rv; 1084 1085 memset(buffer, 0, sizeof(buffer)); 1086 if (count > sizeof(buffer) - 1) 1087 count = sizeof(buffer) - 1; 1088 if (copy_from_user(buffer, buf, count)) 1089 return -EFAULT; 1090 rv = kstrtoint(strstrip(buffer), 10, &itype); 1091 if (rv < 0) 1092 return rv; 1093 type = (enum clear_refs_types)itype; 1094 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1095 return -EINVAL; 1096 1097 task = get_proc_task(file_inode(file)); 1098 if (!task) 1099 return -ESRCH; 1100 mm = get_task_mm(task); 1101 if (mm) { 1102 struct clear_refs_private cp = { 1103 .type = type, 1104 }; 1105 struct mm_walk clear_refs_walk = { 1106 .pmd_entry = clear_refs_pte_range, 1107 .test_walk = clear_refs_test_walk, 1108 .mm = mm, 1109 .private = &cp, 1110 }; 1111 1112 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1113 if (down_write_killable(&mm->mmap_sem)) { 1114 count = -EINTR; 1115 goto out_mm; 1116 } 1117 1118 /* 1119 * Writing 5 to /proc/pid/clear_refs resets the peak 1120 * resident set size to this mm's current rss value. 1121 */ 1122 reset_mm_hiwater_rss(mm); 1123 up_write(&mm->mmap_sem); 1124 goto out_mm; 1125 } 1126 1127 down_read(&mm->mmap_sem); 1128 tlb_gather_mmu(&tlb, mm, 0, -1); 1129 if (type == CLEAR_REFS_SOFT_DIRTY) { 1130 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1131 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1132 continue; 1133 up_read(&mm->mmap_sem); 1134 if (down_write_killable(&mm->mmap_sem)) { 1135 count = -EINTR; 1136 goto out_mm; 1137 } 1138 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1139 vma->vm_flags &= ~VM_SOFTDIRTY; 1140 vma_set_page_prot(vma); 1141 } 1142 downgrade_write(&mm->mmap_sem); 1143 break; 1144 } 1145 mmu_notifier_invalidate_range_start(mm, 0, -1); 1146 } 1147 walk_page_range(0, mm->highest_vm_end, &clear_refs_walk); 1148 if (type == CLEAR_REFS_SOFT_DIRTY) 1149 mmu_notifier_invalidate_range_end(mm, 0, -1); 1150 tlb_finish_mmu(&tlb, 0, -1); 1151 up_read(&mm->mmap_sem); 1152 out_mm: 1153 mmput(mm); 1154 } 1155 put_task_struct(task); 1156 1157 return count; 1158 } 1159 1160 const struct file_operations proc_clear_refs_operations = { 1161 .write = clear_refs_write, 1162 .llseek = noop_llseek, 1163 }; 1164 1165 typedef struct { 1166 u64 pme; 1167 } pagemap_entry_t; 1168 1169 struct pagemapread { 1170 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1171 pagemap_entry_t *buffer; 1172 bool show_pfn; 1173 }; 1174 1175 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1176 #define PAGEMAP_WALK_MASK (PMD_MASK) 1177 1178 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1179 #define PM_PFRAME_BITS 55 1180 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1181 #define PM_SOFT_DIRTY BIT_ULL(55) 1182 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1183 #define PM_FILE BIT_ULL(61) 1184 #define PM_SWAP BIT_ULL(62) 1185 #define PM_PRESENT BIT_ULL(63) 1186 1187 #define PM_END_OF_BUFFER 1 1188 1189 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1190 { 1191 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1192 } 1193 1194 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1195 struct pagemapread *pm) 1196 { 1197 pm->buffer[pm->pos++] = *pme; 1198 if (pm->pos >= pm->len) 1199 return PM_END_OF_BUFFER; 1200 return 0; 1201 } 1202 1203 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1204 struct mm_walk *walk) 1205 { 1206 struct pagemapread *pm = walk->private; 1207 unsigned long addr = start; 1208 int err = 0; 1209 1210 while (addr < end) { 1211 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1212 pagemap_entry_t pme = make_pme(0, 0); 1213 /* End of address space hole, which we mark as non-present. */ 1214 unsigned long hole_end; 1215 1216 if (vma) 1217 hole_end = min(end, vma->vm_start); 1218 else 1219 hole_end = end; 1220 1221 for (; addr < hole_end; addr += PAGE_SIZE) { 1222 err = add_to_pagemap(addr, &pme, pm); 1223 if (err) 1224 goto out; 1225 } 1226 1227 if (!vma) 1228 break; 1229 1230 /* Addresses in the VMA. */ 1231 if (vma->vm_flags & VM_SOFTDIRTY) 1232 pme = make_pme(0, PM_SOFT_DIRTY); 1233 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1234 err = add_to_pagemap(addr, &pme, pm); 1235 if (err) 1236 goto out; 1237 } 1238 } 1239 out: 1240 return err; 1241 } 1242 1243 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1244 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1245 { 1246 u64 frame = 0, flags = 0; 1247 struct page *page = NULL; 1248 1249 if (pte_present(pte)) { 1250 if (pm->show_pfn) 1251 frame = pte_pfn(pte); 1252 flags |= PM_PRESENT; 1253 page = _vm_normal_page(vma, addr, pte, true); 1254 if (pte_soft_dirty(pte)) 1255 flags |= PM_SOFT_DIRTY; 1256 } else if (is_swap_pte(pte)) { 1257 swp_entry_t entry; 1258 if (pte_swp_soft_dirty(pte)) 1259 flags |= PM_SOFT_DIRTY; 1260 entry = pte_to_swp_entry(pte); 1261 frame = swp_type(entry) | 1262 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1263 flags |= PM_SWAP; 1264 if (is_migration_entry(entry)) 1265 page = migration_entry_to_page(entry); 1266 1267 if (is_device_private_entry(entry)) 1268 page = device_private_entry_to_page(entry); 1269 } 1270 1271 if (page && !PageAnon(page)) 1272 flags |= PM_FILE; 1273 if (page && page_mapcount(page) == 1) 1274 flags |= PM_MMAP_EXCLUSIVE; 1275 if (vma->vm_flags & VM_SOFTDIRTY) 1276 flags |= PM_SOFT_DIRTY; 1277 1278 return make_pme(frame, flags); 1279 } 1280 1281 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1282 struct mm_walk *walk) 1283 { 1284 struct vm_area_struct *vma = walk->vma; 1285 struct pagemapread *pm = walk->private; 1286 spinlock_t *ptl; 1287 pte_t *pte, *orig_pte; 1288 int err = 0; 1289 1290 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1291 ptl = pmd_trans_huge_lock(pmdp, vma); 1292 if (ptl) { 1293 u64 flags = 0, frame = 0; 1294 pmd_t pmd = *pmdp; 1295 struct page *page = NULL; 1296 1297 if (vma->vm_flags & VM_SOFTDIRTY) 1298 flags |= PM_SOFT_DIRTY; 1299 1300 if (pmd_present(pmd)) { 1301 page = pmd_page(pmd); 1302 1303 flags |= PM_PRESENT; 1304 if (pmd_soft_dirty(pmd)) 1305 flags |= PM_SOFT_DIRTY; 1306 if (pm->show_pfn) 1307 frame = pmd_pfn(pmd) + 1308 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1309 } 1310 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION 1311 else if (is_swap_pmd(pmd)) { 1312 swp_entry_t entry = pmd_to_swp_entry(pmd); 1313 1314 frame = swp_type(entry) | 1315 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1316 flags |= PM_SWAP; 1317 if (pmd_swp_soft_dirty(pmd)) 1318 flags |= PM_SOFT_DIRTY; 1319 VM_BUG_ON(!is_pmd_migration_entry(pmd)); 1320 page = migration_entry_to_page(entry); 1321 } 1322 #endif 1323 1324 if (page && page_mapcount(page) == 1) 1325 flags |= PM_MMAP_EXCLUSIVE; 1326 1327 for (; addr != end; addr += PAGE_SIZE) { 1328 pagemap_entry_t pme = make_pme(frame, flags); 1329 1330 err = add_to_pagemap(addr, &pme, pm); 1331 if (err) 1332 break; 1333 if (pm->show_pfn && (flags & PM_PRESENT)) 1334 frame++; 1335 } 1336 spin_unlock(ptl); 1337 return err; 1338 } 1339 1340 if (pmd_trans_unstable(pmdp)) 1341 return 0; 1342 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1343 1344 /* 1345 * We can assume that @vma always points to a valid one and @end never 1346 * goes beyond vma->vm_end. 1347 */ 1348 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1349 for (; addr < end; pte++, addr += PAGE_SIZE) { 1350 pagemap_entry_t pme; 1351 1352 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1353 err = add_to_pagemap(addr, &pme, pm); 1354 if (err) 1355 break; 1356 } 1357 pte_unmap_unlock(orig_pte, ptl); 1358 1359 cond_resched(); 1360 1361 return err; 1362 } 1363 1364 #ifdef CONFIG_HUGETLB_PAGE 1365 /* This function walks within one hugetlb entry in the single call */ 1366 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1367 unsigned long addr, unsigned long end, 1368 struct mm_walk *walk) 1369 { 1370 struct pagemapread *pm = walk->private; 1371 struct vm_area_struct *vma = walk->vma; 1372 u64 flags = 0, frame = 0; 1373 int err = 0; 1374 pte_t pte; 1375 1376 if (vma->vm_flags & VM_SOFTDIRTY) 1377 flags |= PM_SOFT_DIRTY; 1378 1379 pte = huge_ptep_get(ptep); 1380 if (pte_present(pte)) { 1381 struct page *page = pte_page(pte); 1382 1383 if (!PageAnon(page)) 1384 flags |= PM_FILE; 1385 1386 if (page_mapcount(page) == 1) 1387 flags |= PM_MMAP_EXCLUSIVE; 1388 1389 flags |= PM_PRESENT; 1390 if (pm->show_pfn) 1391 frame = pte_pfn(pte) + 1392 ((addr & ~hmask) >> PAGE_SHIFT); 1393 } 1394 1395 for (; addr != end; addr += PAGE_SIZE) { 1396 pagemap_entry_t pme = make_pme(frame, flags); 1397 1398 err = add_to_pagemap(addr, &pme, pm); 1399 if (err) 1400 return err; 1401 if (pm->show_pfn && (flags & PM_PRESENT)) 1402 frame++; 1403 } 1404 1405 cond_resched(); 1406 1407 return err; 1408 } 1409 #endif /* HUGETLB_PAGE */ 1410 1411 /* 1412 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1413 * 1414 * For each page in the address space, this file contains one 64-bit entry 1415 * consisting of the following: 1416 * 1417 * Bits 0-54 page frame number (PFN) if present 1418 * Bits 0-4 swap type if swapped 1419 * Bits 5-54 swap offset if swapped 1420 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.rst) 1421 * Bit 56 page exclusively mapped 1422 * Bits 57-60 zero 1423 * Bit 61 page is file-page or shared-anon 1424 * Bit 62 page swapped 1425 * Bit 63 page present 1426 * 1427 * If the page is not present but in swap, then the PFN contains an 1428 * encoding of the swap file number and the page's offset into the 1429 * swap. Unmapped pages return a null PFN. This allows determining 1430 * precisely which pages are mapped (or in swap) and comparing mapped 1431 * pages between processes. 1432 * 1433 * Efficient users of this interface will use /proc/pid/maps to 1434 * determine which areas of memory are actually mapped and llseek to 1435 * skip over unmapped regions. 1436 */ 1437 static ssize_t pagemap_read(struct file *file, char __user *buf, 1438 size_t count, loff_t *ppos) 1439 { 1440 struct mm_struct *mm = file->private_data; 1441 struct pagemapread pm; 1442 struct mm_walk pagemap_walk = {}; 1443 unsigned long src; 1444 unsigned long svpfn; 1445 unsigned long start_vaddr; 1446 unsigned long end_vaddr; 1447 int ret = 0, copied = 0; 1448 1449 if (!mm || !mmget_not_zero(mm)) 1450 goto out; 1451 1452 ret = -EINVAL; 1453 /* file position must be aligned */ 1454 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1455 goto out_mm; 1456 1457 ret = 0; 1458 if (!count) 1459 goto out_mm; 1460 1461 /* do not disclose physical addresses: attack vector */ 1462 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1463 1464 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1465 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_KERNEL); 1466 ret = -ENOMEM; 1467 if (!pm.buffer) 1468 goto out_mm; 1469 1470 pagemap_walk.pmd_entry = pagemap_pmd_range; 1471 pagemap_walk.pte_hole = pagemap_pte_hole; 1472 #ifdef CONFIG_HUGETLB_PAGE 1473 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 1474 #endif 1475 pagemap_walk.mm = mm; 1476 pagemap_walk.private = ± 1477 1478 src = *ppos; 1479 svpfn = src / PM_ENTRY_BYTES; 1480 start_vaddr = svpfn << PAGE_SHIFT; 1481 end_vaddr = mm->task_size; 1482 1483 /* watch out for wraparound */ 1484 if (svpfn > mm->task_size >> PAGE_SHIFT) 1485 start_vaddr = end_vaddr; 1486 1487 /* 1488 * The odds are that this will stop walking way 1489 * before end_vaddr, because the length of the 1490 * user buffer is tracked in "pm", and the walk 1491 * will stop when we hit the end of the buffer. 1492 */ 1493 ret = 0; 1494 while (count && (start_vaddr < end_vaddr)) { 1495 int len; 1496 unsigned long end; 1497 1498 pm.pos = 0; 1499 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1500 /* overflow ? */ 1501 if (end < start_vaddr || end > end_vaddr) 1502 end = end_vaddr; 1503 down_read(&mm->mmap_sem); 1504 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 1505 up_read(&mm->mmap_sem); 1506 start_vaddr = end; 1507 1508 len = min(count, PM_ENTRY_BYTES * pm.pos); 1509 if (copy_to_user(buf, pm.buffer, len)) { 1510 ret = -EFAULT; 1511 goto out_free; 1512 } 1513 copied += len; 1514 buf += len; 1515 count -= len; 1516 } 1517 *ppos += copied; 1518 if (!ret || ret == PM_END_OF_BUFFER) 1519 ret = copied; 1520 1521 out_free: 1522 kfree(pm.buffer); 1523 out_mm: 1524 mmput(mm); 1525 out: 1526 return ret; 1527 } 1528 1529 static int pagemap_open(struct inode *inode, struct file *file) 1530 { 1531 struct mm_struct *mm; 1532 1533 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1534 if (IS_ERR(mm)) 1535 return PTR_ERR(mm); 1536 file->private_data = mm; 1537 return 0; 1538 } 1539 1540 static int pagemap_release(struct inode *inode, struct file *file) 1541 { 1542 struct mm_struct *mm = file->private_data; 1543 1544 if (mm) 1545 mmdrop(mm); 1546 return 0; 1547 } 1548 1549 const struct file_operations proc_pagemap_operations = { 1550 .llseek = mem_lseek, /* borrow this */ 1551 .read = pagemap_read, 1552 .open = pagemap_open, 1553 .release = pagemap_release, 1554 }; 1555 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1556 1557 #ifdef CONFIG_NUMA 1558 1559 struct numa_maps { 1560 unsigned long pages; 1561 unsigned long anon; 1562 unsigned long active; 1563 unsigned long writeback; 1564 unsigned long mapcount_max; 1565 unsigned long dirty; 1566 unsigned long swapcache; 1567 unsigned long node[MAX_NUMNODES]; 1568 }; 1569 1570 struct numa_maps_private { 1571 struct proc_maps_private proc_maps; 1572 struct numa_maps md; 1573 }; 1574 1575 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1576 unsigned long nr_pages) 1577 { 1578 int count = page_mapcount(page); 1579 1580 md->pages += nr_pages; 1581 if (pte_dirty || PageDirty(page)) 1582 md->dirty += nr_pages; 1583 1584 if (PageSwapCache(page)) 1585 md->swapcache += nr_pages; 1586 1587 if (PageActive(page) || PageUnevictable(page)) 1588 md->active += nr_pages; 1589 1590 if (PageWriteback(page)) 1591 md->writeback += nr_pages; 1592 1593 if (PageAnon(page)) 1594 md->anon += nr_pages; 1595 1596 if (count > md->mapcount_max) 1597 md->mapcount_max = count; 1598 1599 md->node[page_to_nid(page)] += nr_pages; 1600 } 1601 1602 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1603 unsigned long addr) 1604 { 1605 struct page *page; 1606 int nid; 1607 1608 if (!pte_present(pte)) 1609 return NULL; 1610 1611 page = vm_normal_page(vma, addr, pte); 1612 if (!page) 1613 return NULL; 1614 1615 if (PageReserved(page)) 1616 return NULL; 1617 1618 nid = page_to_nid(page); 1619 if (!node_isset(nid, node_states[N_MEMORY])) 1620 return NULL; 1621 1622 return page; 1623 } 1624 1625 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1626 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1627 struct vm_area_struct *vma, 1628 unsigned long addr) 1629 { 1630 struct page *page; 1631 int nid; 1632 1633 if (!pmd_present(pmd)) 1634 return NULL; 1635 1636 page = vm_normal_page_pmd(vma, addr, pmd); 1637 if (!page) 1638 return NULL; 1639 1640 if (PageReserved(page)) 1641 return NULL; 1642 1643 nid = page_to_nid(page); 1644 if (!node_isset(nid, node_states[N_MEMORY])) 1645 return NULL; 1646 1647 return page; 1648 } 1649 #endif 1650 1651 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1652 unsigned long end, struct mm_walk *walk) 1653 { 1654 struct numa_maps *md = walk->private; 1655 struct vm_area_struct *vma = walk->vma; 1656 spinlock_t *ptl; 1657 pte_t *orig_pte; 1658 pte_t *pte; 1659 1660 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1661 ptl = pmd_trans_huge_lock(pmd, vma); 1662 if (ptl) { 1663 struct page *page; 1664 1665 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1666 if (page) 1667 gather_stats(page, md, pmd_dirty(*pmd), 1668 HPAGE_PMD_SIZE/PAGE_SIZE); 1669 spin_unlock(ptl); 1670 return 0; 1671 } 1672 1673 if (pmd_trans_unstable(pmd)) 1674 return 0; 1675 #endif 1676 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1677 do { 1678 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1679 if (!page) 1680 continue; 1681 gather_stats(page, md, pte_dirty(*pte), 1); 1682 1683 } while (pte++, addr += PAGE_SIZE, addr != end); 1684 pte_unmap_unlock(orig_pte, ptl); 1685 cond_resched(); 1686 return 0; 1687 } 1688 #ifdef CONFIG_HUGETLB_PAGE 1689 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1690 unsigned long addr, unsigned long end, struct mm_walk *walk) 1691 { 1692 pte_t huge_pte = huge_ptep_get(pte); 1693 struct numa_maps *md; 1694 struct page *page; 1695 1696 if (!pte_present(huge_pte)) 1697 return 0; 1698 1699 page = pte_page(huge_pte); 1700 if (!page) 1701 return 0; 1702 1703 md = walk->private; 1704 gather_stats(page, md, pte_dirty(huge_pte), 1); 1705 return 0; 1706 } 1707 1708 #else 1709 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1710 unsigned long addr, unsigned long end, struct mm_walk *walk) 1711 { 1712 return 0; 1713 } 1714 #endif 1715 1716 /* 1717 * Display pages allocated per node and memory policy via /proc. 1718 */ 1719 static int show_numa_map(struct seq_file *m, void *v, int is_pid) 1720 { 1721 struct numa_maps_private *numa_priv = m->private; 1722 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1723 struct vm_area_struct *vma = v; 1724 struct numa_maps *md = &numa_priv->md; 1725 struct file *file = vma->vm_file; 1726 struct mm_struct *mm = vma->vm_mm; 1727 struct mm_walk walk = { 1728 .hugetlb_entry = gather_hugetlb_stats, 1729 .pmd_entry = gather_pte_stats, 1730 .private = md, 1731 .mm = mm, 1732 }; 1733 struct mempolicy *pol; 1734 char buffer[64]; 1735 int nid; 1736 1737 if (!mm) 1738 return 0; 1739 1740 /* Ensure we start with an empty set of numa_maps statistics. */ 1741 memset(md, 0, sizeof(*md)); 1742 1743 pol = __get_vma_policy(vma, vma->vm_start); 1744 if (pol) { 1745 mpol_to_str(buffer, sizeof(buffer), pol); 1746 mpol_cond_put(pol); 1747 } else { 1748 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1749 } 1750 1751 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1752 1753 if (file) { 1754 seq_puts(m, " file="); 1755 seq_file_path(m, file, "\n\t= "); 1756 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1757 seq_puts(m, " heap"); 1758 } else if (is_stack(vma)) { 1759 seq_puts(m, " stack"); 1760 } 1761 1762 if (is_vm_hugetlb_page(vma)) 1763 seq_puts(m, " huge"); 1764 1765 /* mmap_sem is held by m_start */ 1766 walk_page_vma(vma, &walk); 1767 1768 if (!md->pages) 1769 goto out; 1770 1771 if (md->anon) 1772 seq_printf(m, " anon=%lu", md->anon); 1773 1774 if (md->dirty) 1775 seq_printf(m, " dirty=%lu", md->dirty); 1776 1777 if (md->pages != md->anon && md->pages != md->dirty) 1778 seq_printf(m, " mapped=%lu", md->pages); 1779 1780 if (md->mapcount_max > 1) 1781 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1782 1783 if (md->swapcache) 1784 seq_printf(m, " swapcache=%lu", md->swapcache); 1785 1786 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1787 seq_printf(m, " active=%lu", md->active); 1788 1789 if (md->writeback) 1790 seq_printf(m, " writeback=%lu", md->writeback); 1791 1792 for_each_node_state(nid, N_MEMORY) 1793 if (md->node[nid]) 1794 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1795 1796 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1797 out: 1798 seq_putc(m, '\n'); 1799 m_cache_vma(m, vma); 1800 return 0; 1801 } 1802 1803 static int show_pid_numa_map(struct seq_file *m, void *v) 1804 { 1805 return show_numa_map(m, v, 1); 1806 } 1807 1808 static int show_tid_numa_map(struct seq_file *m, void *v) 1809 { 1810 return show_numa_map(m, v, 0); 1811 } 1812 1813 static const struct seq_operations proc_pid_numa_maps_op = { 1814 .start = m_start, 1815 .next = m_next, 1816 .stop = m_stop, 1817 .show = show_pid_numa_map, 1818 }; 1819 1820 static const struct seq_operations proc_tid_numa_maps_op = { 1821 .start = m_start, 1822 .next = m_next, 1823 .stop = m_stop, 1824 .show = show_tid_numa_map, 1825 }; 1826 1827 static int numa_maps_open(struct inode *inode, struct file *file, 1828 const struct seq_operations *ops) 1829 { 1830 return proc_maps_open(inode, file, ops, 1831 sizeof(struct numa_maps_private)); 1832 } 1833 1834 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1835 { 1836 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1837 } 1838 1839 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1840 { 1841 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1842 } 1843 1844 const struct file_operations proc_pid_numa_maps_operations = { 1845 .open = pid_numa_maps_open, 1846 .read = seq_read, 1847 .llseek = seq_lseek, 1848 .release = proc_map_release, 1849 }; 1850 1851 const struct file_operations proc_tid_numa_maps_operations = { 1852 .open = tid_numa_maps_open, 1853 .read = seq_read, 1854 .llseek = seq_lseek, 1855 .release = proc_map_release, 1856 }; 1857 #endif /* CONFIG_NUMA */ 1858