1 #include <linux/mm.h> 2 #include <linux/vmacache.h> 3 #include <linux/hugetlb.h> 4 #include <linux/huge_mm.h> 5 #include <linux/mount.h> 6 #include <linux/seq_file.h> 7 #include <linux/highmem.h> 8 #include <linux/ptrace.h> 9 #include <linux/slab.h> 10 #include <linux/pagemap.h> 11 #include <linux/mempolicy.h> 12 #include <linux/rmap.h> 13 #include <linux/swap.h> 14 #include <linux/sched/mm.h> 15 #include <linux/swapops.h> 16 #include <linux/mmu_notifier.h> 17 #include <linux/page_idle.h> 18 #include <linux/shmem_fs.h> 19 20 #include <asm/elf.h> 21 #include <linux/uaccess.h> 22 #include <asm/tlbflush.h> 23 #include "internal.h" 24 25 void task_mem(struct seq_file *m, struct mm_struct *mm) 26 { 27 unsigned long text, lib, swap, ptes, pmds, anon, file, shmem; 28 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 29 30 anon = get_mm_counter(mm, MM_ANONPAGES); 31 file = get_mm_counter(mm, MM_FILEPAGES); 32 shmem = get_mm_counter(mm, MM_SHMEMPAGES); 33 34 /* 35 * Note: to minimize their overhead, mm maintains hiwater_vm and 36 * hiwater_rss only when about to *lower* total_vm or rss. Any 37 * collector of these hiwater stats must therefore get total_vm 38 * and rss too, which will usually be the higher. Barriers? not 39 * worth the effort, such snapshots can always be inconsistent. 40 */ 41 hiwater_vm = total_vm = mm->total_vm; 42 if (hiwater_vm < mm->hiwater_vm) 43 hiwater_vm = mm->hiwater_vm; 44 hiwater_rss = total_rss = anon + file + shmem; 45 if (hiwater_rss < mm->hiwater_rss) 46 hiwater_rss = mm->hiwater_rss; 47 48 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; 49 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; 50 swap = get_mm_counter(mm, MM_SWAPENTS); 51 ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes); 52 pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm); 53 seq_printf(m, 54 "VmPeak:\t%8lu kB\n" 55 "VmSize:\t%8lu kB\n" 56 "VmLck:\t%8lu kB\n" 57 "VmPin:\t%8lu kB\n" 58 "VmHWM:\t%8lu kB\n" 59 "VmRSS:\t%8lu kB\n" 60 "RssAnon:\t%8lu kB\n" 61 "RssFile:\t%8lu kB\n" 62 "RssShmem:\t%8lu kB\n" 63 "VmData:\t%8lu kB\n" 64 "VmStk:\t%8lu kB\n" 65 "VmExe:\t%8lu kB\n" 66 "VmLib:\t%8lu kB\n" 67 "VmPTE:\t%8lu kB\n" 68 "VmPMD:\t%8lu kB\n" 69 "VmSwap:\t%8lu kB\n", 70 hiwater_vm << (PAGE_SHIFT-10), 71 total_vm << (PAGE_SHIFT-10), 72 mm->locked_vm << (PAGE_SHIFT-10), 73 mm->pinned_vm << (PAGE_SHIFT-10), 74 hiwater_rss << (PAGE_SHIFT-10), 75 total_rss << (PAGE_SHIFT-10), 76 anon << (PAGE_SHIFT-10), 77 file << (PAGE_SHIFT-10), 78 shmem << (PAGE_SHIFT-10), 79 mm->data_vm << (PAGE_SHIFT-10), 80 mm->stack_vm << (PAGE_SHIFT-10), text, lib, 81 ptes >> 10, 82 pmds >> 10, 83 swap << (PAGE_SHIFT-10)); 84 hugetlb_report_usage(m, mm); 85 } 86 87 unsigned long task_vsize(struct mm_struct *mm) 88 { 89 return PAGE_SIZE * mm->total_vm; 90 } 91 92 unsigned long task_statm(struct mm_struct *mm, 93 unsigned long *shared, unsigned long *text, 94 unsigned long *data, unsigned long *resident) 95 { 96 *shared = get_mm_counter(mm, MM_FILEPAGES) + 97 get_mm_counter(mm, MM_SHMEMPAGES); 98 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 99 >> PAGE_SHIFT; 100 *data = mm->data_vm + mm->stack_vm; 101 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 102 return mm->total_vm; 103 } 104 105 #ifdef CONFIG_NUMA 106 /* 107 * Save get_task_policy() for show_numa_map(). 108 */ 109 static void hold_task_mempolicy(struct proc_maps_private *priv) 110 { 111 struct task_struct *task = priv->task; 112 113 task_lock(task); 114 priv->task_mempolicy = get_task_policy(task); 115 mpol_get(priv->task_mempolicy); 116 task_unlock(task); 117 } 118 static void release_task_mempolicy(struct proc_maps_private *priv) 119 { 120 mpol_put(priv->task_mempolicy); 121 } 122 #else 123 static void hold_task_mempolicy(struct proc_maps_private *priv) 124 { 125 } 126 static void release_task_mempolicy(struct proc_maps_private *priv) 127 { 128 } 129 #endif 130 131 static void vma_stop(struct proc_maps_private *priv) 132 { 133 struct mm_struct *mm = priv->mm; 134 135 release_task_mempolicy(priv); 136 up_read(&mm->mmap_sem); 137 mmput(mm); 138 } 139 140 static struct vm_area_struct * 141 m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma) 142 { 143 if (vma == priv->tail_vma) 144 return NULL; 145 return vma->vm_next ?: priv->tail_vma; 146 } 147 148 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma) 149 { 150 if (m->count < m->size) /* vma is copied successfully */ 151 m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL; 152 } 153 154 static void *m_start(struct seq_file *m, loff_t *ppos) 155 { 156 struct proc_maps_private *priv = m->private; 157 unsigned long last_addr = m->version; 158 struct mm_struct *mm; 159 struct vm_area_struct *vma; 160 unsigned int pos = *ppos; 161 162 /* See m_cache_vma(). Zero at the start or after lseek. */ 163 if (last_addr == -1UL) 164 return NULL; 165 166 priv->task = get_proc_task(priv->inode); 167 if (!priv->task) 168 return ERR_PTR(-ESRCH); 169 170 mm = priv->mm; 171 if (!mm || !mmget_not_zero(mm)) 172 return NULL; 173 174 down_read(&mm->mmap_sem); 175 hold_task_mempolicy(priv); 176 priv->tail_vma = get_gate_vma(mm); 177 178 if (last_addr) { 179 vma = find_vma(mm, last_addr - 1); 180 if (vma && vma->vm_start <= last_addr) 181 vma = m_next_vma(priv, vma); 182 if (vma) 183 return vma; 184 } 185 186 m->version = 0; 187 if (pos < mm->map_count) { 188 for (vma = mm->mmap; pos; pos--) { 189 m->version = vma->vm_start; 190 vma = vma->vm_next; 191 } 192 return vma; 193 } 194 195 /* we do not bother to update m->version in this case */ 196 if (pos == mm->map_count && priv->tail_vma) 197 return priv->tail_vma; 198 199 vma_stop(priv); 200 return NULL; 201 } 202 203 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 204 { 205 struct proc_maps_private *priv = m->private; 206 struct vm_area_struct *next; 207 208 (*pos)++; 209 next = m_next_vma(priv, v); 210 if (!next) 211 vma_stop(priv); 212 return next; 213 } 214 215 static void m_stop(struct seq_file *m, void *v) 216 { 217 struct proc_maps_private *priv = m->private; 218 219 if (!IS_ERR_OR_NULL(v)) 220 vma_stop(priv); 221 if (priv->task) { 222 put_task_struct(priv->task); 223 priv->task = NULL; 224 } 225 } 226 227 static int proc_maps_open(struct inode *inode, struct file *file, 228 const struct seq_operations *ops, int psize) 229 { 230 struct proc_maps_private *priv = __seq_open_private(file, ops, psize); 231 232 if (!priv) 233 return -ENOMEM; 234 235 priv->inode = inode; 236 priv->mm = proc_mem_open(inode, PTRACE_MODE_READ); 237 if (IS_ERR(priv->mm)) { 238 int err = PTR_ERR(priv->mm); 239 240 seq_release_private(inode, file); 241 return err; 242 } 243 244 return 0; 245 } 246 247 static int proc_map_release(struct inode *inode, struct file *file) 248 { 249 struct seq_file *seq = file->private_data; 250 struct proc_maps_private *priv = seq->private; 251 252 if (priv->mm) 253 mmdrop(priv->mm); 254 255 return seq_release_private(inode, file); 256 } 257 258 static int do_maps_open(struct inode *inode, struct file *file, 259 const struct seq_operations *ops) 260 { 261 return proc_maps_open(inode, file, ops, 262 sizeof(struct proc_maps_private)); 263 } 264 265 /* 266 * Indicate if the VMA is a stack for the given task; for 267 * /proc/PID/maps that is the stack of the main task. 268 */ 269 static int is_stack(struct proc_maps_private *priv, 270 struct vm_area_struct *vma) 271 { 272 /* 273 * We make no effort to guess what a given thread considers to be 274 * its "stack". It's not even well-defined for programs written 275 * languages like Go. 276 */ 277 return vma->vm_start <= vma->vm_mm->start_stack && 278 vma->vm_end >= vma->vm_mm->start_stack; 279 } 280 281 static void 282 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid) 283 { 284 struct mm_struct *mm = vma->vm_mm; 285 struct file *file = vma->vm_file; 286 struct proc_maps_private *priv = m->private; 287 vm_flags_t flags = vma->vm_flags; 288 unsigned long ino = 0; 289 unsigned long long pgoff = 0; 290 unsigned long start, end; 291 dev_t dev = 0; 292 const char *name = NULL; 293 294 if (file) { 295 struct inode *inode = file_inode(vma->vm_file); 296 dev = inode->i_sb->s_dev; 297 ino = inode->i_ino; 298 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 299 } 300 301 /* We don't show the stack guard page in /proc/maps */ 302 start = vma->vm_start; 303 if (stack_guard_page_start(vma, start)) 304 start += PAGE_SIZE; 305 end = vma->vm_end; 306 if (stack_guard_page_end(vma, end)) 307 end -= PAGE_SIZE; 308 309 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 310 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ", 311 start, 312 end, 313 flags & VM_READ ? 'r' : '-', 314 flags & VM_WRITE ? 'w' : '-', 315 flags & VM_EXEC ? 'x' : '-', 316 flags & VM_MAYSHARE ? 's' : 'p', 317 pgoff, 318 MAJOR(dev), MINOR(dev), ino); 319 320 /* 321 * Print the dentry name for named mappings, and a 322 * special [heap] marker for the heap: 323 */ 324 if (file) { 325 seq_pad(m, ' '); 326 seq_file_path(m, file, "\n"); 327 goto done; 328 } 329 330 if (vma->vm_ops && vma->vm_ops->name) { 331 name = vma->vm_ops->name(vma); 332 if (name) 333 goto done; 334 } 335 336 name = arch_vma_name(vma); 337 if (!name) { 338 if (!mm) { 339 name = "[vdso]"; 340 goto done; 341 } 342 343 if (vma->vm_start <= mm->brk && 344 vma->vm_end >= mm->start_brk) { 345 name = "[heap]"; 346 goto done; 347 } 348 349 if (is_stack(priv, vma)) 350 name = "[stack]"; 351 } 352 353 done: 354 if (name) { 355 seq_pad(m, ' '); 356 seq_puts(m, name); 357 } 358 seq_putc(m, '\n'); 359 } 360 361 static int show_map(struct seq_file *m, void *v, int is_pid) 362 { 363 show_map_vma(m, v, is_pid); 364 m_cache_vma(m, v); 365 return 0; 366 } 367 368 static int show_pid_map(struct seq_file *m, void *v) 369 { 370 return show_map(m, v, 1); 371 } 372 373 static int show_tid_map(struct seq_file *m, void *v) 374 { 375 return show_map(m, v, 0); 376 } 377 378 static const struct seq_operations proc_pid_maps_op = { 379 .start = m_start, 380 .next = m_next, 381 .stop = m_stop, 382 .show = show_pid_map 383 }; 384 385 static const struct seq_operations proc_tid_maps_op = { 386 .start = m_start, 387 .next = m_next, 388 .stop = m_stop, 389 .show = show_tid_map 390 }; 391 392 static int pid_maps_open(struct inode *inode, struct file *file) 393 { 394 return do_maps_open(inode, file, &proc_pid_maps_op); 395 } 396 397 static int tid_maps_open(struct inode *inode, struct file *file) 398 { 399 return do_maps_open(inode, file, &proc_tid_maps_op); 400 } 401 402 const struct file_operations proc_pid_maps_operations = { 403 .open = pid_maps_open, 404 .read = seq_read, 405 .llseek = seq_lseek, 406 .release = proc_map_release, 407 }; 408 409 const struct file_operations proc_tid_maps_operations = { 410 .open = tid_maps_open, 411 .read = seq_read, 412 .llseek = seq_lseek, 413 .release = proc_map_release, 414 }; 415 416 /* 417 * Proportional Set Size(PSS): my share of RSS. 418 * 419 * PSS of a process is the count of pages it has in memory, where each 420 * page is divided by the number of processes sharing it. So if a 421 * process has 1000 pages all to itself, and 1000 shared with one other 422 * process, its PSS will be 1500. 423 * 424 * To keep (accumulated) division errors low, we adopt a 64bit 425 * fixed-point pss counter to minimize division errors. So (pss >> 426 * PSS_SHIFT) would be the real byte count. 427 * 428 * A shift of 12 before division means (assuming 4K page size): 429 * - 1M 3-user-pages add up to 8KB errors; 430 * - supports mapcount up to 2^24, or 16M; 431 * - supports PSS up to 2^52 bytes, or 4PB. 432 */ 433 #define PSS_SHIFT 12 434 435 #ifdef CONFIG_PROC_PAGE_MONITOR 436 struct mem_size_stats { 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 u64 pss; 451 u64 swap_pss; 452 bool check_shmem_swap; 453 }; 454 455 static void smaps_account(struct mem_size_stats *mss, struct page *page, 456 bool compound, bool young, bool dirty) 457 { 458 int i, nr = compound ? 1 << compound_order(page) : 1; 459 unsigned long size = nr * PAGE_SIZE; 460 461 if (PageAnon(page)) { 462 mss->anonymous += size; 463 if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) 464 mss->lazyfree += size; 465 } 466 467 mss->resident += size; 468 /* Accumulate the size in pages that have been accessed. */ 469 if (young || page_is_young(page) || PageReferenced(page)) 470 mss->referenced += size; 471 472 /* 473 * page_count(page) == 1 guarantees the page is mapped exactly once. 474 * If any subpage of the compound page mapped with PTE it would elevate 475 * page_count(). 476 */ 477 if (page_count(page) == 1) { 478 if (dirty || PageDirty(page)) 479 mss->private_dirty += size; 480 else 481 mss->private_clean += size; 482 mss->pss += (u64)size << PSS_SHIFT; 483 return; 484 } 485 486 for (i = 0; i < nr; i++, page++) { 487 int mapcount = page_mapcount(page); 488 489 if (mapcount >= 2) { 490 if (dirty || PageDirty(page)) 491 mss->shared_dirty += PAGE_SIZE; 492 else 493 mss->shared_clean += PAGE_SIZE; 494 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount; 495 } else { 496 if (dirty || PageDirty(page)) 497 mss->private_dirty += PAGE_SIZE; 498 else 499 mss->private_clean += PAGE_SIZE; 500 mss->pss += PAGE_SIZE << PSS_SHIFT; 501 } 502 } 503 } 504 505 #ifdef CONFIG_SHMEM 506 static int smaps_pte_hole(unsigned long addr, unsigned long end, 507 struct mm_walk *walk) 508 { 509 struct mem_size_stats *mss = walk->private; 510 511 mss->swap += shmem_partial_swap_usage( 512 walk->vma->vm_file->f_mapping, addr, end); 513 514 return 0; 515 } 516 #endif 517 518 static void smaps_pte_entry(pte_t *pte, unsigned long addr, 519 struct mm_walk *walk) 520 { 521 struct mem_size_stats *mss = walk->private; 522 struct vm_area_struct *vma = walk->vma; 523 struct page *page = NULL; 524 525 if (pte_present(*pte)) { 526 page = vm_normal_page(vma, addr, *pte); 527 } else if (is_swap_pte(*pte)) { 528 swp_entry_t swpent = pte_to_swp_entry(*pte); 529 530 if (!non_swap_entry(swpent)) { 531 int mapcount; 532 533 mss->swap += PAGE_SIZE; 534 mapcount = swp_swapcount(swpent); 535 if (mapcount >= 2) { 536 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; 537 538 do_div(pss_delta, mapcount); 539 mss->swap_pss += pss_delta; 540 } else { 541 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; 542 } 543 } else if (is_migration_entry(swpent)) 544 page = migration_entry_to_page(swpent); 545 } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap 546 && pte_none(*pte))) { 547 page = find_get_entry(vma->vm_file->f_mapping, 548 linear_page_index(vma, addr)); 549 if (!page) 550 return; 551 552 if (radix_tree_exceptional_entry(page)) 553 mss->swap += PAGE_SIZE; 554 else 555 put_page(page); 556 557 return; 558 } 559 560 if (!page) 561 return; 562 563 smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte)); 564 } 565 566 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 567 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 568 struct mm_walk *walk) 569 { 570 struct mem_size_stats *mss = walk->private; 571 struct vm_area_struct *vma = walk->vma; 572 struct page *page; 573 574 /* FOLL_DUMP will return -EFAULT on huge zero page */ 575 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP); 576 if (IS_ERR_OR_NULL(page)) 577 return; 578 if (PageAnon(page)) 579 mss->anonymous_thp += HPAGE_PMD_SIZE; 580 else if (PageSwapBacked(page)) 581 mss->shmem_thp += HPAGE_PMD_SIZE; 582 else if (is_zone_device_page(page)) 583 /* pass */; 584 else 585 VM_BUG_ON_PAGE(1, page); 586 smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd)); 587 } 588 #else 589 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, 590 struct mm_walk *walk) 591 { 592 } 593 #endif 594 595 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 596 struct mm_walk *walk) 597 { 598 struct vm_area_struct *vma = walk->vma; 599 pte_t *pte; 600 spinlock_t *ptl; 601 602 ptl = pmd_trans_huge_lock(pmd, vma); 603 if (ptl) { 604 smaps_pmd_entry(pmd, addr, walk); 605 spin_unlock(ptl); 606 return 0; 607 } 608 609 if (pmd_trans_unstable(pmd)) 610 return 0; 611 /* 612 * The mmap_sem held all the way back in m_start() is what 613 * keeps khugepaged out of here and from collapsing things 614 * in here. 615 */ 616 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 617 for (; addr != end; pte++, addr += PAGE_SIZE) 618 smaps_pte_entry(pte, addr, walk); 619 pte_unmap_unlock(pte - 1, ptl); 620 cond_resched(); 621 return 0; 622 } 623 624 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 625 { 626 /* 627 * Don't forget to update Documentation/ on changes. 628 */ 629 static const char mnemonics[BITS_PER_LONG][2] = { 630 /* 631 * In case if we meet a flag we don't know about. 632 */ 633 [0 ... (BITS_PER_LONG-1)] = "??", 634 635 [ilog2(VM_READ)] = "rd", 636 [ilog2(VM_WRITE)] = "wr", 637 [ilog2(VM_EXEC)] = "ex", 638 [ilog2(VM_SHARED)] = "sh", 639 [ilog2(VM_MAYREAD)] = "mr", 640 [ilog2(VM_MAYWRITE)] = "mw", 641 [ilog2(VM_MAYEXEC)] = "me", 642 [ilog2(VM_MAYSHARE)] = "ms", 643 [ilog2(VM_GROWSDOWN)] = "gd", 644 [ilog2(VM_PFNMAP)] = "pf", 645 [ilog2(VM_DENYWRITE)] = "dw", 646 #ifdef CONFIG_X86_INTEL_MPX 647 [ilog2(VM_MPX)] = "mp", 648 #endif 649 [ilog2(VM_LOCKED)] = "lo", 650 [ilog2(VM_IO)] = "io", 651 [ilog2(VM_SEQ_READ)] = "sr", 652 [ilog2(VM_RAND_READ)] = "rr", 653 [ilog2(VM_DONTCOPY)] = "dc", 654 [ilog2(VM_DONTEXPAND)] = "de", 655 [ilog2(VM_ACCOUNT)] = "ac", 656 [ilog2(VM_NORESERVE)] = "nr", 657 [ilog2(VM_HUGETLB)] = "ht", 658 [ilog2(VM_ARCH_1)] = "ar", 659 [ilog2(VM_DONTDUMP)] = "dd", 660 #ifdef CONFIG_MEM_SOFT_DIRTY 661 [ilog2(VM_SOFTDIRTY)] = "sd", 662 #endif 663 [ilog2(VM_MIXEDMAP)] = "mm", 664 [ilog2(VM_HUGEPAGE)] = "hg", 665 [ilog2(VM_NOHUGEPAGE)] = "nh", 666 [ilog2(VM_MERGEABLE)] = "mg", 667 [ilog2(VM_UFFD_MISSING)]= "um", 668 [ilog2(VM_UFFD_WP)] = "uw", 669 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS 670 /* These come out via ProtectionKey: */ 671 [ilog2(VM_PKEY_BIT0)] = "", 672 [ilog2(VM_PKEY_BIT1)] = "", 673 [ilog2(VM_PKEY_BIT2)] = "", 674 [ilog2(VM_PKEY_BIT3)] = "", 675 #endif 676 }; 677 size_t i; 678 679 seq_puts(m, "VmFlags: "); 680 for (i = 0; i < BITS_PER_LONG; i++) { 681 if (!mnemonics[i][0]) 682 continue; 683 if (vma->vm_flags & (1UL << i)) { 684 seq_printf(m, "%c%c ", 685 mnemonics[i][0], mnemonics[i][1]); 686 } 687 } 688 seq_putc(m, '\n'); 689 } 690 691 #ifdef CONFIG_HUGETLB_PAGE 692 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, 693 unsigned long addr, unsigned long end, 694 struct mm_walk *walk) 695 { 696 struct mem_size_stats *mss = walk->private; 697 struct vm_area_struct *vma = walk->vma; 698 struct page *page = NULL; 699 700 if (pte_present(*pte)) { 701 page = vm_normal_page(vma, addr, *pte); 702 } else if (is_swap_pte(*pte)) { 703 swp_entry_t swpent = pte_to_swp_entry(*pte); 704 705 if (is_migration_entry(swpent)) 706 page = migration_entry_to_page(swpent); 707 } 708 if (page) { 709 int mapcount = page_mapcount(page); 710 711 if (mapcount >= 2) 712 mss->shared_hugetlb += huge_page_size(hstate_vma(vma)); 713 else 714 mss->private_hugetlb += huge_page_size(hstate_vma(vma)); 715 } 716 return 0; 717 } 718 #endif /* HUGETLB_PAGE */ 719 720 void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma) 721 { 722 } 723 724 static int show_smap(struct seq_file *m, void *v, int is_pid) 725 { 726 struct vm_area_struct *vma = v; 727 struct mem_size_stats mss; 728 struct mm_walk smaps_walk = { 729 .pmd_entry = smaps_pte_range, 730 #ifdef CONFIG_HUGETLB_PAGE 731 .hugetlb_entry = smaps_hugetlb_range, 732 #endif 733 .mm = vma->vm_mm, 734 .private = &mss, 735 }; 736 737 memset(&mss, 0, sizeof mss); 738 739 #ifdef CONFIG_SHMEM 740 if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) { 741 /* 742 * For shared or readonly shmem mappings we know that all 743 * swapped out pages belong to the shmem object, and we can 744 * obtain the swap value much more efficiently. For private 745 * writable mappings, we might have COW pages that are 746 * not affected by the parent swapped out pages of the shmem 747 * object, so we have to distinguish them during the page walk. 748 * Unless we know that the shmem object (or the part mapped by 749 * our VMA) has no swapped out pages at all. 750 */ 751 unsigned long shmem_swapped = shmem_swap_usage(vma); 752 753 if (!shmem_swapped || (vma->vm_flags & VM_SHARED) || 754 !(vma->vm_flags & VM_WRITE)) { 755 mss.swap = shmem_swapped; 756 } else { 757 mss.check_shmem_swap = true; 758 smaps_walk.pte_hole = smaps_pte_hole; 759 } 760 } 761 #endif 762 763 /* mmap_sem is held in m_start */ 764 walk_page_vma(vma, &smaps_walk); 765 766 show_map_vma(m, vma, is_pid); 767 768 seq_printf(m, 769 "Size: %8lu kB\n" 770 "Rss: %8lu kB\n" 771 "Pss: %8lu kB\n" 772 "Shared_Clean: %8lu kB\n" 773 "Shared_Dirty: %8lu kB\n" 774 "Private_Clean: %8lu kB\n" 775 "Private_Dirty: %8lu kB\n" 776 "Referenced: %8lu kB\n" 777 "Anonymous: %8lu kB\n" 778 "LazyFree: %8lu kB\n" 779 "AnonHugePages: %8lu kB\n" 780 "ShmemPmdMapped: %8lu kB\n" 781 "Shared_Hugetlb: %8lu kB\n" 782 "Private_Hugetlb: %7lu kB\n" 783 "Swap: %8lu kB\n" 784 "SwapPss: %8lu kB\n" 785 "KernelPageSize: %8lu kB\n" 786 "MMUPageSize: %8lu kB\n" 787 "Locked: %8lu kB\n", 788 (vma->vm_end - vma->vm_start) >> 10, 789 mss.resident >> 10, 790 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)), 791 mss.shared_clean >> 10, 792 mss.shared_dirty >> 10, 793 mss.private_clean >> 10, 794 mss.private_dirty >> 10, 795 mss.referenced >> 10, 796 mss.anonymous >> 10, 797 mss.lazyfree >> 10, 798 mss.anonymous_thp >> 10, 799 mss.shmem_thp >> 10, 800 mss.shared_hugetlb >> 10, 801 mss.private_hugetlb >> 10, 802 mss.swap >> 10, 803 (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)), 804 vma_kernel_pagesize(vma) >> 10, 805 vma_mmu_pagesize(vma) >> 10, 806 (vma->vm_flags & VM_LOCKED) ? 807 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0); 808 809 arch_show_smap(m, vma); 810 show_smap_vma_flags(m, vma); 811 m_cache_vma(m, vma); 812 return 0; 813 } 814 815 static int show_pid_smap(struct seq_file *m, void *v) 816 { 817 return show_smap(m, v, 1); 818 } 819 820 static int show_tid_smap(struct seq_file *m, void *v) 821 { 822 return show_smap(m, v, 0); 823 } 824 825 static const struct seq_operations proc_pid_smaps_op = { 826 .start = m_start, 827 .next = m_next, 828 .stop = m_stop, 829 .show = show_pid_smap 830 }; 831 832 static const struct seq_operations proc_tid_smaps_op = { 833 .start = m_start, 834 .next = m_next, 835 .stop = m_stop, 836 .show = show_tid_smap 837 }; 838 839 static int pid_smaps_open(struct inode *inode, struct file *file) 840 { 841 return do_maps_open(inode, file, &proc_pid_smaps_op); 842 } 843 844 static int tid_smaps_open(struct inode *inode, struct file *file) 845 { 846 return do_maps_open(inode, file, &proc_tid_smaps_op); 847 } 848 849 const struct file_operations proc_pid_smaps_operations = { 850 .open = pid_smaps_open, 851 .read = seq_read, 852 .llseek = seq_lseek, 853 .release = proc_map_release, 854 }; 855 856 const struct file_operations proc_tid_smaps_operations = { 857 .open = tid_smaps_open, 858 .read = seq_read, 859 .llseek = seq_lseek, 860 .release = proc_map_release, 861 }; 862 863 enum clear_refs_types { 864 CLEAR_REFS_ALL = 1, 865 CLEAR_REFS_ANON, 866 CLEAR_REFS_MAPPED, 867 CLEAR_REFS_SOFT_DIRTY, 868 CLEAR_REFS_MM_HIWATER_RSS, 869 CLEAR_REFS_LAST, 870 }; 871 872 struct clear_refs_private { 873 enum clear_refs_types type; 874 }; 875 876 #ifdef CONFIG_MEM_SOFT_DIRTY 877 static inline void clear_soft_dirty(struct vm_area_struct *vma, 878 unsigned long addr, pte_t *pte) 879 { 880 /* 881 * The soft-dirty tracker uses #PF-s to catch writes 882 * to pages, so write-protect the pte as well. See the 883 * Documentation/vm/soft-dirty.txt for full description 884 * of how soft-dirty works. 885 */ 886 pte_t ptent = *pte; 887 888 if (pte_present(ptent)) { 889 ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte); 890 ptent = pte_wrprotect(ptent); 891 ptent = pte_clear_soft_dirty(ptent); 892 ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent); 893 } else if (is_swap_pte(ptent)) { 894 ptent = pte_swp_clear_soft_dirty(ptent); 895 set_pte_at(vma->vm_mm, addr, pte, ptent); 896 } 897 } 898 #else 899 static inline void clear_soft_dirty(struct vm_area_struct *vma, 900 unsigned long addr, pte_t *pte) 901 { 902 } 903 #endif 904 905 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) 906 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 907 unsigned long addr, pmd_t *pmdp) 908 { 909 pmd_t pmd = *pmdp; 910 911 /* See comment in change_huge_pmd() */ 912 pmdp_invalidate(vma, addr, pmdp); 913 if (pmd_dirty(*pmdp)) 914 pmd = pmd_mkdirty(pmd); 915 if (pmd_young(*pmdp)) 916 pmd = pmd_mkyoung(pmd); 917 918 pmd = pmd_wrprotect(pmd); 919 pmd = pmd_clear_soft_dirty(pmd); 920 921 set_pmd_at(vma->vm_mm, addr, pmdp, pmd); 922 } 923 #else 924 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, 925 unsigned long addr, pmd_t *pmdp) 926 { 927 } 928 #endif 929 930 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 931 unsigned long end, struct mm_walk *walk) 932 { 933 struct clear_refs_private *cp = walk->private; 934 struct vm_area_struct *vma = walk->vma; 935 pte_t *pte, ptent; 936 spinlock_t *ptl; 937 struct page *page; 938 939 ptl = pmd_trans_huge_lock(pmd, vma); 940 if (ptl) { 941 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 942 clear_soft_dirty_pmd(vma, addr, pmd); 943 goto out; 944 } 945 946 page = pmd_page(*pmd); 947 948 /* Clear accessed and referenced bits. */ 949 pmdp_test_and_clear_young(vma, addr, pmd); 950 test_and_clear_page_young(page); 951 ClearPageReferenced(page); 952 out: 953 spin_unlock(ptl); 954 return 0; 955 } 956 957 if (pmd_trans_unstable(pmd)) 958 return 0; 959 960 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 961 for (; addr != end; pte++, addr += PAGE_SIZE) { 962 ptent = *pte; 963 964 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 965 clear_soft_dirty(vma, addr, pte); 966 continue; 967 } 968 969 if (!pte_present(ptent)) 970 continue; 971 972 page = vm_normal_page(vma, addr, ptent); 973 if (!page) 974 continue; 975 976 /* Clear accessed and referenced bits. */ 977 ptep_test_and_clear_young(vma, addr, pte); 978 test_and_clear_page_young(page); 979 ClearPageReferenced(page); 980 } 981 pte_unmap_unlock(pte - 1, ptl); 982 cond_resched(); 983 return 0; 984 } 985 986 static int clear_refs_test_walk(unsigned long start, unsigned long end, 987 struct mm_walk *walk) 988 { 989 struct clear_refs_private *cp = walk->private; 990 struct vm_area_struct *vma = walk->vma; 991 992 if (vma->vm_flags & VM_PFNMAP) 993 return 1; 994 995 /* 996 * Writing 1 to /proc/pid/clear_refs affects all pages. 997 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages. 998 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages. 999 * Writing 4 to /proc/pid/clear_refs affects all pages. 1000 */ 1001 if (cp->type == CLEAR_REFS_ANON && vma->vm_file) 1002 return 1; 1003 if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file) 1004 return 1; 1005 return 0; 1006 } 1007 1008 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 1009 size_t count, loff_t *ppos) 1010 { 1011 struct task_struct *task; 1012 char buffer[PROC_NUMBUF]; 1013 struct mm_struct *mm; 1014 struct vm_area_struct *vma; 1015 enum clear_refs_types type; 1016 int itype; 1017 int rv; 1018 1019 memset(buffer, 0, sizeof(buffer)); 1020 if (count > sizeof(buffer) - 1) 1021 count = sizeof(buffer) - 1; 1022 if (copy_from_user(buffer, buf, count)) 1023 return -EFAULT; 1024 rv = kstrtoint(strstrip(buffer), 10, &itype); 1025 if (rv < 0) 1026 return rv; 1027 type = (enum clear_refs_types)itype; 1028 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 1029 return -EINVAL; 1030 1031 task = get_proc_task(file_inode(file)); 1032 if (!task) 1033 return -ESRCH; 1034 mm = get_task_mm(task); 1035 if (mm) { 1036 struct clear_refs_private cp = { 1037 .type = type, 1038 }; 1039 struct mm_walk clear_refs_walk = { 1040 .pmd_entry = clear_refs_pte_range, 1041 .test_walk = clear_refs_test_walk, 1042 .mm = mm, 1043 .private = &cp, 1044 }; 1045 1046 if (type == CLEAR_REFS_MM_HIWATER_RSS) { 1047 if (down_write_killable(&mm->mmap_sem)) { 1048 count = -EINTR; 1049 goto out_mm; 1050 } 1051 1052 /* 1053 * Writing 5 to /proc/pid/clear_refs resets the peak 1054 * resident set size to this mm's current rss value. 1055 */ 1056 reset_mm_hiwater_rss(mm); 1057 up_write(&mm->mmap_sem); 1058 goto out_mm; 1059 } 1060 1061 down_read(&mm->mmap_sem); 1062 if (type == CLEAR_REFS_SOFT_DIRTY) { 1063 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1064 if (!(vma->vm_flags & VM_SOFTDIRTY)) 1065 continue; 1066 up_read(&mm->mmap_sem); 1067 if (down_write_killable(&mm->mmap_sem)) { 1068 count = -EINTR; 1069 goto out_mm; 1070 } 1071 for (vma = mm->mmap; vma; vma = vma->vm_next) { 1072 vma->vm_flags &= ~VM_SOFTDIRTY; 1073 vma_set_page_prot(vma); 1074 } 1075 downgrade_write(&mm->mmap_sem); 1076 break; 1077 } 1078 mmu_notifier_invalidate_range_start(mm, 0, -1); 1079 } 1080 walk_page_range(0, mm->highest_vm_end, &clear_refs_walk); 1081 if (type == CLEAR_REFS_SOFT_DIRTY) 1082 mmu_notifier_invalidate_range_end(mm, 0, -1); 1083 flush_tlb_mm(mm); 1084 up_read(&mm->mmap_sem); 1085 out_mm: 1086 mmput(mm); 1087 } 1088 put_task_struct(task); 1089 1090 return count; 1091 } 1092 1093 const struct file_operations proc_clear_refs_operations = { 1094 .write = clear_refs_write, 1095 .llseek = noop_llseek, 1096 }; 1097 1098 typedef struct { 1099 u64 pme; 1100 } pagemap_entry_t; 1101 1102 struct pagemapread { 1103 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 1104 pagemap_entry_t *buffer; 1105 bool show_pfn; 1106 }; 1107 1108 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 1109 #define PAGEMAP_WALK_MASK (PMD_MASK) 1110 1111 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 1112 #define PM_PFRAME_BITS 55 1113 #define PM_PFRAME_MASK GENMASK_ULL(PM_PFRAME_BITS - 1, 0) 1114 #define PM_SOFT_DIRTY BIT_ULL(55) 1115 #define PM_MMAP_EXCLUSIVE BIT_ULL(56) 1116 #define PM_FILE BIT_ULL(61) 1117 #define PM_SWAP BIT_ULL(62) 1118 #define PM_PRESENT BIT_ULL(63) 1119 1120 #define PM_END_OF_BUFFER 1 1121 1122 static inline pagemap_entry_t make_pme(u64 frame, u64 flags) 1123 { 1124 return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags }; 1125 } 1126 1127 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 1128 struct pagemapread *pm) 1129 { 1130 pm->buffer[pm->pos++] = *pme; 1131 if (pm->pos >= pm->len) 1132 return PM_END_OF_BUFFER; 1133 return 0; 1134 } 1135 1136 static int pagemap_pte_hole(unsigned long start, unsigned long end, 1137 struct mm_walk *walk) 1138 { 1139 struct pagemapread *pm = walk->private; 1140 unsigned long addr = start; 1141 int err = 0; 1142 1143 while (addr < end) { 1144 struct vm_area_struct *vma = find_vma(walk->mm, addr); 1145 pagemap_entry_t pme = make_pme(0, 0); 1146 /* End of address space hole, which we mark as non-present. */ 1147 unsigned long hole_end; 1148 1149 if (vma) 1150 hole_end = min(end, vma->vm_start); 1151 else 1152 hole_end = end; 1153 1154 for (; addr < hole_end; addr += PAGE_SIZE) { 1155 err = add_to_pagemap(addr, &pme, pm); 1156 if (err) 1157 goto out; 1158 } 1159 1160 if (!vma) 1161 break; 1162 1163 /* Addresses in the VMA. */ 1164 if (vma->vm_flags & VM_SOFTDIRTY) 1165 pme = make_pme(0, PM_SOFT_DIRTY); 1166 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) { 1167 err = add_to_pagemap(addr, &pme, pm); 1168 if (err) 1169 goto out; 1170 } 1171 } 1172 out: 1173 return err; 1174 } 1175 1176 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, 1177 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 1178 { 1179 u64 frame = 0, flags = 0; 1180 struct page *page = NULL; 1181 1182 if (pte_present(pte)) { 1183 if (pm->show_pfn) 1184 frame = pte_pfn(pte); 1185 flags |= PM_PRESENT; 1186 page = vm_normal_page(vma, addr, pte); 1187 if (pte_soft_dirty(pte)) 1188 flags |= PM_SOFT_DIRTY; 1189 } else if (is_swap_pte(pte)) { 1190 swp_entry_t entry; 1191 if (pte_swp_soft_dirty(pte)) 1192 flags |= PM_SOFT_DIRTY; 1193 entry = pte_to_swp_entry(pte); 1194 frame = swp_type(entry) | 1195 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 1196 flags |= PM_SWAP; 1197 if (is_migration_entry(entry)) 1198 page = migration_entry_to_page(entry); 1199 } 1200 1201 if (page && !PageAnon(page)) 1202 flags |= PM_FILE; 1203 if (page && page_mapcount(page) == 1) 1204 flags |= PM_MMAP_EXCLUSIVE; 1205 if (vma->vm_flags & VM_SOFTDIRTY) 1206 flags |= PM_SOFT_DIRTY; 1207 1208 return make_pme(frame, flags); 1209 } 1210 1211 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, 1212 struct mm_walk *walk) 1213 { 1214 struct vm_area_struct *vma = walk->vma; 1215 struct pagemapread *pm = walk->private; 1216 spinlock_t *ptl; 1217 pte_t *pte, *orig_pte; 1218 int err = 0; 1219 1220 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1221 ptl = pmd_trans_huge_lock(pmdp, vma); 1222 if (ptl) { 1223 u64 flags = 0, frame = 0; 1224 pmd_t pmd = *pmdp; 1225 1226 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd)) 1227 flags |= PM_SOFT_DIRTY; 1228 1229 /* 1230 * Currently pmd for thp is always present because thp 1231 * can not be swapped-out, migrated, or HWPOISONed 1232 * (split in such cases instead.) 1233 * This if-check is just to prepare for future implementation. 1234 */ 1235 if (pmd_present(pmd)) { 1236 struct page *page = pmd_page(pmd); 1237 1238 if (page_mapcount(page) == 1) 1239 flags |= PM_MMAP_EXCLUSIVE; 1240 1241 flags |= PM_PRESENT; 1242 if (pm->show_pfn) 1243 frame = pmd_pfn(pmd) + 1244 ((addr & ~PMD_MASK) >> PAGE_SHIFT); 1245 } 1246 1247 for (; addr != end; addr += PAGE_SIZE) { 1248 pagemap_entry_t pme = make_pme(frame, flags); 1249 1250 err = add_to_pagemap(addr, &pme, pm); 1251 if (err) 1252 break; 1253 if (pm->show_pfn && (flags & PM_PRESENT)) 1254 frame++; 1255 } 1256 spin_unlock(ptl); 1257 return err; 1258 } 1259 1260 if (pmd_trans_unstable(pmdp)) 1261 return 0; 1262 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 1263 1264 /* 1265 * We can assume that @vma always points to a valid one and @end never 1266 * goes beyond vma->vm_end. 1267 */ 1268 orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl); 1269 for (; addr < end; pte++, addr += PAGE_SIZE) { 1270 pagemap_entry_t pme; 1271 1272 pme = pte_to_pagemap_entry(pm, vma, addr, *pte); 1273 err = add_to_pagemap(addr, &pme, pm); 1274 if (err) 1275 break; 1276 } 1277 pte_unmap_unlock(orig_pte, ptl); 1278 1279 cond_resched(); 1280 1281 return err; 1282 } 1283 1284 #ifdef CONFIG_HUGETLB_PAGE 1285 /* This function walks within one hugetlb entry in the single call */ 1286 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, 1287 unsigned long addr, unsigned long end, 1288 struct mm_walk *walk) 1289 { 1290 struct pagemapread *pm = walk->private; 1291 struct vm_area_struct *vma = walk->vma; 1292 u64 flags = 0, frame = 0; 1293 int err = 0; 1294 pte_t pte; 1295 1296 if (vma->vm_flags & VM_SOFTDIRTY) 1297 flags |= PM_SOFT_DIRTY; 1298 1299 pte = huge_ptep_get(ptep); 1300 if (pte_present(pte)) { 1301 struct page *page = pte_page(pte); 1302 1303 if (!PageAnon(page)) 1304 flags |= PM_FILE; 1305 1306 if (page_mapcount(page) == 1) 1307 flags |= PM_MMAP_EXCLUSIVE; 1308 1309 flags |= PM_PRESENT; 1310 if (pm->show_pfn) 1311 frame = pte_pfn(pte) + 1312 ((addr & ~hmask) >> PAGE_SHIFT); 1313 } 1314 1315 for (; addr != end; addr += PAGE_SIZE) { 1316 pagemap_entry_t pme = make_pme(frame, flags); 1317 1318 err = add_to_pagemap(addr, &pme, pm); 1319 if (err) 1320 return err; 1321 if (pm->show_pfn && (flags & PM_PRESENT)) 1322 frame++; 1323 } 1324 1325 cond_resched(); 1326 1327 return err; 1328 } 1329 #endif /* HUGETLB_PAGE */ 1330 1331 /* 1332 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1333 * 1334 * For each page in the address space, this file contains one 64-bit entry 1335 * consisting of the following: 1336 * 1337 * Bits 0-54 page frame number (PFN) if present 1338 * Bits 0-4 swap type if swapped 1339 * Bits 5-54 swap offset if swapped 1340 * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt) 1341 * Bit 56 page exclusively mapped 1342 * Bits 57-60 zero 1343 * Bit 61 page is file-page or shared-anon 1344 * Bit 62 page swapped 1345 * Bit 63 page present 1346 * 1347 * If the page is not present but in swap, then the PFN contains an 1348 * encoding of the swap file number and the page's offset into the 1349 * swap. Unmapped pages return a null PFN. This allows determining 1350 * precisely which pages are mapped (or in swap) and comparing mapped 1351 * pages between processes. 1352 * 1353 * Efficient users of this interface will use /proc/pid/maps to 1354 * determine which areas of memory are actually mapped and llseek to 1355 * skip over unmapped regions. 1356 */ 1357 static ssize_t pagemap_read(struct file *file, char __user *buf, 1358 size_t count, loff_t *ppos) 1359 { 1360 struct mm_struct *mm = file->private_data; 1361 struct pagemapread pm; 1362 struct mm_walk pagemap_walk = {}; 1363 unsigned long src; 1364 unsigned long svpfn; 1365 unsigned long start_vaddr; 1366 unsigned long end_vaddr; 1367 int ret = 0, copied = 0; 1368 1369 if (!mm || !mmget_not_zero(mm)) 1370 goto out; 1371 1372 ret = -EINVAL; 1373 /* file position must be aligned */ 1374 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1375 goto out_mm; 1376 1377 ret = 0; 1378 if (!count) 1379 goto out_mm; 1380 1381 /* do not disclose physical addresses: attack vector */ 1382 pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN); 1383 1384 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1385 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY); 1386 ret = -ENOMEM; 1387 if (!pm.buffer) 1388 goto out_mm; 1389 1390 pagemap_walk.pmd_entry = pagemap_pmd_range; 1391 pagemap_walk.pte_hole = pagemap_pte_hole; 1392 #ifdef CONFIG_HUGETLB_PAGE 1393 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 1394 #endif 1395 pagemap_walk.mm = mm; 1396 pagemap_walk.private = ± 1397 1398 src = *ppos; 1399 svpfn = src / PM_ENTRY_BYTES; 1400 start_vaddr = svpfn << PAGE_SHIFT; 1401 end_vaddr = mm->task_size; 1402 1403 /* watch out for wraparound */ 1404 if (svpfn > mm->task_size >> PAGE_SHIFT) 1405 start_vaddr = end_vaddr; 1406 1407 /* 1408 * The odds are that this will stop walking way 1409 * before end_vaddr, because the length of the 1410 * user buffer is tracked in "pm", and the walk 1411 * will stop when we hit the end of the buffer. 1412 */ 1413 ret = 0; 1414 while (count && (start_vaddr < end_vaddr)) { 1415 int len; 1416 unsigned long end; 1417 1418 pm.pos = 0; 1419 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1420 /* overflow ? */ 1421 if (end < start_vaddr || end > end_vaddr) 1422 end = end_vaddr; 1423 down_read(&mm->mmap_sem); 1424 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 1425 up_read(&mm->mmap_sem); 1426 start_vaddr = end; 1427 1428 len = min(count, PM_ENTRY_BYTES * pm.pos); 1429 if (copy_to_user(buf, pm.buffer, len)) { 1430 ret = -EFAULT; 1431 goto out_free; 1432 } 1433 copied += len; 1434 buf += len; 1435 count -= len; 1436 } 1437 *ppos += copied; 1438 if (!ret || ret == PM_END_OF_BUFFER) 1439 ret = copied; 1440 1441 out_free: 1442 kfree(pm.buffer); 1443 out_mm: 1444 mmput(mm); 1445 out: 1446 return ret; 1447 } 1448 1449 static int pagemap_open(struct inode *inode, struct file *file) 1450 { 1451 struct mm_struct *mm; 1452 1453 mm = proc_mem_open(inode, PTRACE_MODE_READ); 1454 if (IS_ERR(mm)) 1455 return PTR_ERR(mm); 1456 file->private_data = mm; 1457 return 0; 1458 } 1459 1460 static int pagemap_release(struct inode *inode, struct file *file) 1461 { 1462 struct mm_struct *mm = file->private_data; 1463 1464 if (mm) 1465 mmdrop(mm); 1466 return 0; 1467 } 1468 1469 const struct file_operations proc_pagemap_operations = { 1470 .llseek = mem_lseek, /* borrow this */ 1471 .read = pagemap_read, 1472 .open = pagemap_open, 1473 .release = pagemap_release, 1474 }; 1475 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1476 1477 #ifdef CONFIG_NUMA 1478 1479 struct numa_maps { 1480 unsigned long pages; 1481 unsigned long anon; 1482 unsigned long active; 1483 unsigned long writeback; 1484 unsigned long mapcount_max; 1485 unsigned long dirty; 1486 unsigned long swapcache; 1487 unsigned long node[MAX_NUMNODES]; 1488 }; 1489 1490 struct numa_maps_private { 1491 struct proc_maps_private proc_maps; 1492 struct numa_maps md; 1493 }; 1494 1495 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1496 unsigned long nr_pages) 1497 { 1498 int count = page_mapcount(page); 1499 1500 md->pages += nr_pages; 1501 if (pte_dirty || PageDirty(page)) 1502 md->dirty += nr_pages; 1503 1504 if (PageSwapCache(page)) 1505 md->swapcache += nr_pages; 1506 1507 if (PageActive(page) || PageUnevictable(page)) 1508 md->active += nr_pages; 1509 1510 if (PageWriteback(page)) 1511 md->writeback += nr_pages; 1512 1513 if (PageAnon(page)) 1514 md->anon += nr_pages; 1515 1516 if (count > md->mapcount_max) 1517 md->mapcount_max = count; 1518 1519 md->node[page_to_nid(page)] += nr_pages; 1520 } 1521 1522 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1523 unsigned long addr) 1524 { 1525 struct page *page; 1526 int nid; 1527 1528 if (!pte_present(pte)) 1529 return NULL; 1530 1531 page = vm_normal_page(vma, addr, pte); 1532 if (!page) 1533 return NULL; 1534 1535 if (PageReserved(page)) 1536 return NULL; 1537 1538 nid = page_to_nid(page); 1539 if (!node_isset(nid, node_states[N_MEMORY])) 1540 return NULL; 1541 1542 return page; 1543 } 1544 1545 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1546 static struct page *can_gather_numa_stats_pmd(pmd_t pmd, 1547 struct vm_area_struct *vma, 1548 unsigned long addr) 1549 { 1550 struct page *page; 1551 int nid; 1552 1553 if (!pmd_present(pmd)) 1554 return NULL; 1555 1556 page = vm_normal_page_pmd(vma, addr, pmd); 1557 if (!page) 1558 return NULL; 1559 1560 if (PageReserved(page)) 1561 return NULL; 1562 1563 nid = page_to_nid(page); 1564 if (!node_isset(nid, node_states[N_MEMORY])) 1565 return NULL; 1566 1567 return page; 1568 } 1569 #endif 1570 1571 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1572 unsigned long end, struct mm_walk *walk) 1573 { 1574 struct numa_maps *md = walk->private; 1575 struct vm_area_struct *vma = walk->vma; 1576 spinlock_t *ptl; 1577 pte_t *orig_pte; 1578 pte_t *pte; 1579 1580 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1581 ptl = pmd_trans_huge_lock(pmd, vma); 1582 if (ptl) { 1583 struct page *page; 1584 1585 page = can_gather_numa_stats_pmd(*pmd, vma, addr); 1586 if (page) 1587 gather_stats(page, md, pmd_dirty(*pmd), 1588 HPAGE_PMD_SIZE/PAGE_SIZE); 1589 spin_unlock(ptl); 1590 return 0; 1591 } 1592 1593 if (pmd_trans_unstable(pmd)) 1594 return 0; 1595 #endif 1596 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1597 do { 1598 struct page *page = can_gather_numa_stats(*pte, vma, addr); 1599 if (!page) 1600 continue; 1601 gather_stats(page, md, pte_dirty(*pte), 1); 1602 1603 } while (pte++, addr += PAGE_SIZE, addr != end); 1604 pte_unmap_unlock(orig_pte, ptl); 1605 cond_resched(); 1606 return 0; 1607 } 1608 #ifdef CONFIG_HUGETLB_PAGE 1609 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1610 unsigned long addr, unsigned long end, struct mm_walk *walk) 1611 { 1612 pte_t huge_pte = huge_ptep_get(pte); 1613 struct numa_maps *md; 1614 struct page *page; 1615 1616 if (!pte_present(huge_pte)) 1617 return 0; 1618 1619 page = pte_page(huge_pte); 1620 if (!page) 1621 return 0; 1622 1623 md = walk->private; 1624 gather_stats(page, md, pte_dirty(huge_pte), 1); 1625 return 0; 1626 } 1627 1628 #else 1629 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask, 1630 unsigned long addr, unsigned long end, struct mm_walk *walk) 1631 { 1632 return 0; 1633 } 1634 #endif 1635 1636 /* 1637 * Display pages allocated per node and memory policy via /proc. 1638 */ 1639 static int show_numa_map(struct seq_file *m, void *v, int is_pid) 1640 { 1641 struct numa_maps_private *numa_priv = m->private; 1642 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1643 struct vm_area_struct *vma = v; 1644 struct numa_maps *md = &numa_priv->md; 1645 struct file *file = vma->vm_file; 1646 struct mm_struct *mm = vma->vm_mm; 1647 struct mm_walk walk = { 1648 .hugetlb_entry = gather_hugetlb_stats, 1649 .pmd_entry = gather_pte_stats, 1650 .private = md, 1651 .mm = mm, 1652 }; 1653 struct mempolicy *pol; 1654 char buffer[64]; 1655 int nid; 1656 1657 if (!mm) 1658 return 0; 1659 1660 /* Ensure we start with an empty set of numa_maps statistics. */ 1661 memset(md, 0, sizeof(*md)); 1662 1663 pol = __get_vma_policy(vma, vma->vm_start); 1664 if (pol) { 1665 mpol_to_str(buffer, sizeof(buffer), pol); 1666 mpol_cond_put(pol); 1667 } else { 1668 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy); 1669 } 1670 1671 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1672 1673 if (file) { 1674 seq_puts(m, " file="); 1675 seq_file_path(m, file, "\n\t= "); 1676 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1677 seq_puts(m, " heap"); 1678 } else if (is_stack(proc_priv, vma)) { 1679 seq_puts(m, " stack"); 1680 } 1681 1682 if (is_vm_hugetlb_page(vma)) 1683 seq_puts(m, " huge"); 1684 1685 /* mmap_sem is held by m_start */ 1686 walk_page_vma(vma, &walk); 1687 1688 if (!md->pages) 1689 goto out; 1690 1691 if (md->anon) 1692 seq_printf(m, " anon=%lu", md->anon); 1693 1694 if (md->dirty) 1695 seq_printf(m, " dirty=%lu", md->dirty); 1696 1697 if (md->pages != md->anon && md->pages != md->dirty) 1698 seq_printf(m, " mapped=%lu", md->pages); 1699 1700 if (md->mapcount_max > 1) 1701 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1702 1703 if (md->swapcache) 1704 seq_printf(m, " swapcache=%lu", md->swapcache); 1705 1706 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1707 seq_printf(m, " active=%lu", md->active); 1708 1709 if (md->writeback) 1710 seq_printf(m, " writeback=%lu", md->writeback); 1711 1712 for_each_node_state(nid, N_MEMORY) 1713 if (md->node[nid]) 1714 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1715 1716 seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10); 1717 out: 1718 seq_putc(m, '\n'); 1719 m_cache_vma(m, vma); 1720 return 0; 1721 } 1722 1723 static int show_pid_numa_map(struct seq_file *m, void *v) 1724 { 1725 return show_numa_map(m, v, 1); 1726 } 1727 1728 static int show_tid_numa_map(struct seq_file *m, void *v) 1729 { 1730 return show_numa_map(m, v, 0); 1731 } 1732 1733 static const struct seq_operations proc_pid_numa_maps_op = { 1734 .start = m_start, 1735 .next = m_next, 1736 .stop = m_stop, 1737 .show = show_pid_numa_map, 1738 }; 1739 1740 static const struct seq_operations proc_tid_numa_maps_op = { 1741 .start = m_start, 1742 .next = m_next, 1743 .stop = m_stop, 1744 .show = show_tid_numa_map, 1745 }; 1746 1747 static int numa_maps_open(struct inode *inode, struct file *file, 1748 const struct seq_operations *ops) 1749 { 1750 return proc_maps_open(inode, file, ops, 1751 sizeof(struct numa_maps_private)); 1752 } 1753 1754 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1755 { 1756 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1757 } 1758 1759 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1760 { 1761 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1762 } 1763 1764 const struct file_operations proc_pid_numa_maps_operations = { 1765 .open = pid_numa_maps_open, 1766 .read = seq_read, 1767 .llseek = seq_lseek, 1768 .release = proc_map_release, 1769 }; 1770 1771 const struct file_operations proc_tid_numa_maps_operations = { 1772 .open = tid_numa_maps_open, 1773 .read = seq_read, 1774 .llseek = seq_lseek, 1775 .release = proc_map_release, 1776 }; 1777 #endif /* CONFIG_NUMA */ 1778