1 #include <linux/mm.h> 2 #include <linux/hugetlb.h> 3 #include <linux/huge_mm.h> 4 #include <linux/mount.h> 5 #include <linux/seq_file.h> 6 #include <linux/highmem.h> 7 #include <linux/ptrace.h> 8 #include <linux/slab.h> 9 #include <linux/pagemap.h> 10 #include <linux/mempolicy.h> 11 #include <linux/rmap.h> 12 #include <linux/swap.h> 13 #include <linux/swapops.h> 14 15 #include <asm/elf.h> 16 #include <asm/uaccess.h> 17 #include <asm/tlbflush.h> 18 #include "internal.h" 19 20 void task_mem(struct seq_file *m, struct mm_struct *mm) 21 { 22 unsigned long data, text, lib, swap; 23 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 24 25 /* 26 * Note: to minimize their overhead, mm maintains hiwater_vm and 27 * hiwater_rss only when about to *lower* total_vm or rss. Any 28 * collector of these hiwater stats must therefore get total_vm 29 * and rss too, which will usually be the higher. Barriers? not 30 * worth the effort, such snapshots can always be inconsistent. 31 */ 32 hiwater_vm = total_vm = mm->total_vm; 33 if (hiwater_vm < mm->hiwater_vm) 34 hiwater_vm = mm->hiwater_vm; 35 hiwater_rss = total_rss = get_mm_rss(mm); 36 if (hiwater_rss < mm->hiwater_rss) 37 hiwater_rss = mm->hiwater_rss; 38 39 data = mm->total_vm - mm->shared_vm - mm->stack_vm; 40 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; 41 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; 42 swap = get_mm_counter(mm, MM_SWAPENTS); 43 seq_printf(m, 44 "VmPeak:\t%8lu kB\n" 45 "VmSize:\t%8lu kB\n" 46 "VmLck:\t%8lu kB\n" 47 "VmPin:\t%8lu kB\n" 48 "VmHWM:\t%8lu kB\n" 49 "VmRSS:\t%8lu kB\n" 50 "VmData:\t%8lu kB\n" 51 "VmStk:\t%8lu kB\n" 52 "VmExe:\t%8lu kB\n" 53 "VmLib:\t%8lu kB\n" 54 "VmPTE:\t%8lu kB\n" 55 "VmSwap:\t%8lu kB\n", 56 hiwater_vm << (PAGE_SHIFT-10), 57 (total_vm - mm->reserved_vm) << (PAGE_SHIFT-10), 58 mm->locked_vm << (PAGE_SHIFT-10), 59 mm->pinned_vm << (PAGE_SHIFT-10), 60 hiwater_rss << (PAGE_SHIFT-10), 61 total_rss << (PAGE_SHIFT-10), 62 data << (PAGE_SHIFT-10), 63 mm->stack_vm << (PAGE_SHIFT-10), text, lib, 64 (PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10, 65 swap << (PAGE_SHIFT-10)); 66 } 67 68 unsigned long task_vsize(struct mm_struct *mm) 69 { 70 return PAGE_SIZE * mm->total_vm; 71 } 72 73 unsigned long task_statm(struct mm_struct *mm, 74 unsigned long *shared, unsigned long *text, 75 unsigned long *data, unsigned long *resident) 76 { 77 *shared = get_mm_counter(mm, MM_FILEPAGES); 78 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 79 >> PAGE_SHIFT; 80 *data = mm->total_vm - mm->shared_vm; 81 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 82 return mm->total_vm; 83 } 84 85 static void pad_len_spaces(struct seq_file *m, int len) 86 { 87 len = 25 + sizeof(void*) * 6 - len; 88 if (len < 1) 89 len = 1; 90 seq_printf(m, "%*c", len, ' '); 91 } 92 93 static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma) 94 { 95 if (vma && vma != priv->tail_vma) { 96 struct mm_struct *mm = vma->vm_mm; 97 up_read(&mm->mmap_sem); 98 mmput(mm); 99 } 100 } 101 102 static void *m_start(struct seq_file *m, loff_t *pos) 103 { 104 struct proc_maps_private *priv = m->private; 105 unsigned long last_addr = m->version; 106 struct mm_struct *mm; 107 struct vm_area_struct *vma, *tail_vma = NULL; 108 loff_t l = *pos; 109 110 /* Clear the per syscall fields in priv */ 111 priv->task = NULL; 112 priv->tail_vma = NULL; 113 114 /* 115 * We remember last_addr rather than next_addr to hit with 116 * mmap_cache most of the time. We have zero last_addr at 117 * the beginning and also after lseek. We will have -1 last_addr 118 * after the end of the vmas. 119 */ 120 121 if (last_addr == -1UL) 122 return NULL; 123 124 priv->task = get_pid_task(priv->pid, PIDTYPE_PID); 125 if (!priv->task) 126 return ERR_PTR(-ESRCH); 127 128 mm = mm_access(priv->task, PTRACE_MODE_READ); 129 if (!mm || IS_ERR(mm)) 130 return mm; 131 down_read(&mm->mmap_sem); 132 133 tail_vma = get_gate_vma(priv->task->mm); 134 priv->tail_vma = tail_vma; 135 136 /* Start with last addr hint */ 137 vma = find_vma(mm, last_addr); 138 if (last_addr && vma) { 139 vma = vma->vm_next; 140 goto out; 141 } 142 143 /* 144 * Check the vma index is within the range and do 145 * sequential scan until m_index. 146 */ 147 vma = NULL; 148 if ((unsigned long)l < mm->map_count) { 149 vma = mm->mmap; 150 while (l-- && vma) 151 vma = vma->vm_next; 152 goto out; 153 } 154 155 if (l != mm->map_count) 156 tail_vma = NULL; /* After gate vma */ 157 158 out: 159 if (vma) 160 return vma; 161 162 /* End of vmas has been reached */ 163 m->version = (tail_vma != NULL)? 0: -1UL; 164 up_read(&mm->mmap_sem); 165 mmput(mm); 166 return tail_vma; 167 } 168 169 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 170 { 171 struct proc_maps_private *priv = m->private; 172 struct vm_area_struct *vma = v; 173 struct vm_area_struct *tail_vma = priv->tail_vma; 174 175 (*pos)++; 176 if (vma && (vma != tail_vma) && vma->vm_next) 177 return vma->vm_next; 178 vma_stop(priv, vma); 179 return (vma != tail_vma)? tail_vma: NULL; 180 } 181 182 static void m_stop(struct seq_file *m, void *v) 183 { 184 struct proc_maps_private *priv = m->private; 185 struct vm_area_struct *vma = v; 186 187 if (!IS_ERR(vma)) 188 vma_stop(priv, vma); 189 if (priv->task) 190 put_task_struct(priv->task); 191 } 192 193 static int do_maps_open(struct inode *inode, struct file *file, 194 const struct seq_operations *ops) 195 { 196 struct proc_maps_private *priv; 197 int ret = -ENOMEM; 198 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 199 if (priv) { 200 priv->pid = proc_pid(inode); 201 ret = seq_open(file, ops); 202 if (!ret) { 203 struct seq_file *m = file->private_data; 204 m->private = priv; 205 } else { 206 kfree(priv); 207 } 208 } 209 return ret; 210 } 211 212 static void 213 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid) 214 { 215 struct mm_struct *mm = vma->vm_mm; 216 struct file *file = vma->vm_file; 217 struct proc_maps_private *priv = m->private; 218 struct task_struct *task = priv->task; 219 vm_flags_t flags = vma->vm_flags; 220 unsigned long ino = 0; 221 unsigned long long pgoff = 0; 222 unsigned long start, end; 223 dev_t dev = 0; 224 int len; 225 const char *name = NULL; 226 227 if (file) { 228 struct inode *inode = vma->vm_file->f_path.dentry->d_inode; 229 dev = inode->i_sb->s_dev; 230 ino = inode->i_ino; 231 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 232 } 233 234 /* We don't show the stack guard page in /proc/maps */ 235 start = vma->vm_start; 236 if (stack_guard_page_start(vma, start)) 237 start += PAGE_SIZE; 238 end = vma->vm_end; 239 if (stack_guard_page_end(vma, end)) 240 end -= PAGE_SIZE; 241 242 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n", 243 start, 244 end, 245 flags & VM_READ ? 'r' : '-', 246 flags & VM_WRITE ? 'w' : '-', 247 flags & VM_EXEC ? 'x' : '-', 248 flags & VM_MAYSHARE ? 's' : 'p', 249 pgoff, 250 MAJOR(dev), MINOR(dev), ino, &len); 251 252 /* 253 * Print the dentry name for named mappings, and a 254 * special [heap] marker for the heap: 255 */ 256 if (file) { 257 pad_len_spaces(m, len); 258 seq_path(m, &file->f_path, "\n"); 259 goto done; 260 } 261 262 name = arch_vma_name(vma); 263 if (!name) { 264 pid_t tid; 265 266 if (!mm) { 267 name = "[vdso]"; 268 goto done; 269 } 270 271 if (vma->vm_start <= mm->brk && 272 vma->vm_end >= mm->start_brk) { 273 name = "[heap]"; 274 goto done; 275 } 276 277 tid = vm_is_stack(task, vma, is_pid); 278 279 if (tid != 0) { 280 /* 281 * Thread stack in /proc/PID/task/TID/maps or 282 * the main process stack. 283 */ 284 if (!is_pid || (vma->vm_start <= mm->start_stack && 285 vma->vm_end >= mm->start_stack)) { 286 name = "[stack]"; 287 } else { 288 /* Thread stack in /proc/PID/maps */ 289 pad_len_spaces(m, len); 290 seq_printf(m, "[stack:%d]", tid); 291 } 292 } 293 } 294 295 done: 296 if (name) { 297 pad_len_spaces(m, len); 298 seq_puts(m, name); 299 } 300 seq_putc(m, '\n'); 301 } 302 303 static int show_map(struct seq_file *m, void *v, int is_pid) 304 { 305 struct vm_area_struct *vma = v; 306 struct proc_maps_private *priv = m->private; 307 struct task_struct *task = priv->task; 308 309 show_map_vma(m, vma, is_pid); 310 311 if (m->count < m->size) /* vma is copied successfully */ 312 m->version = (vma != get_gate_vma(task->mm)) 313 ? vma->vm_start : 0; 314 return 0; 315 } 316 317 static int show_pid_map(struct seq_file *m, void *v) 318 { 319 return show_map(m, v, 1); 320 } 321 322 static int show_tid_map(struct seq_file *m, void *v) 323 { 324 return show_map(m, v, 0); 325 } 326 327 static const struct seq_operations proc_pid_maps_op = { 328 .start = m_start, 329 .next = m_next, 330 .stop = m_stop, 331 .show = show_pid_map 332 }; 333 334 static const struct seq_operations proc_tid_maps_op = { 335 .start = m_start, 336 .next = m_next, 337 .stop = m_stop, 338 .show = show_tid_map 339 }; 340 341 static int pid_maps_open(struct inode *inode, struct file *file) 342 { 343 return do_maps_open(inode, file, &proc_pid_maps_op); 344 } 345 346 static int tid_maps_open(struct inode *inode, struct file *file) 347 { 348 return do_maps_open(inode, file, &proc_tid_maps_op); 349 } 350 351 const struct file_operations proc_pid_maps_operations = { 352 .open = pid_maps_open, 353 .read = seq_read, 354 .llseek = seq_lseek, 355 .release = seq_release_private, 356 }; 357 358 const struct file_operations proc_tid_maps_operations = { 359 .open = tid_maps_open, 360 .read = seq_read, 361 .llseek = seq_lseek, 362 .release = seq_release_private, 363 }; 364 365 /* 366 * Proportional Set Size(PSS): my share of RSS. 367 * 368 * PSS of a process is the count of pages it has in memory, where each 369 * page is divided by the number of processes sharing it. So if a 370 * process has 1000 pages all to itself, and 1000 shared with one other 371 * process, its PSS will be 1500. 372 * 373 * To keep (accumulated) division errors low, we adopt a 64bit 374 * fixed-point pss counter to minimize division errors. So (pss >> 375 * PSS_SHIFT) would be the real byte count. 376 * 377 * A shift of 12 before division means (assuming 4K page size): 378 * - 1M 3-user-pages add up to 8KB errors; 379 * - supports mapcount up to 2^24, or 16M; 380 * - supports PSS up to 2^52 bytes, or 4PB. 381 */ 382 #define PSS_SHIFT 12 383 384 #ifdef CONFIG_PROC_PAGE_MONITOR 385 struct mem_size_stats { 386 struct vm_area_struct *vma; 387 unsigned long resident; 388 unsigned long shared_clean; 389 unsigned long shared_dirty; 390 unsigned long private_clean; 391 unsigned long private_dirty; 392 unsigned long referenced; 393 unsigned long anonymous; 394 unsigned long anonymous_thp; 395 unsigned long swap; 396 unsigned long nonlinear; 397 u64 pss; 398 }; 399 400 401 static void smaps_pte_entry(pte_t ptent, unsigned long addr, 402 unsigned long ptent_size, struct mm_walk *walk) 403 { 404 struct mem_size_stats *mss = walk->private; 405 struct vm_area_struct *vma = mss->vma; 406 pgoff_t pgoff = linear_page_index(vma, addr); 407 struct page *page = NULL; 408 int mapcount; 409 410 if (pte_present(ptent)) { 411 page = vm_normal_page(vma, addr, ptent); 412 } else if (is_swap_pte(ptent)) { 413 swp_entry_t swpent = pte_to_swp_entry(ptent); 414 415 if (!non_swap_entry(swpent)) 416 mss->swap += ptent_size; 417 else if (is_migration_entry(swpent)) 418 page = migration_entry_to_page(swpent); 419 } else if (pte_file(ptent)) { 420 if (pte_to_pgoff(ptent) != pgoff) 421 mss->nonlinear += ptent_size; 422 } 423 424 if (!page) 425 return; 426 427 if (PageAnon(page)) 428 mss->anonymous += ptent_size; 429 430 if (page->index != pgoff) 431 mss->nonlinear += ptent_size; 432 433 mss->resident += ptent_size; 434 /* Accumulate the size in pages that have been accessed. */ 435 if (pte_young(ptent) || PageReferenced(page)) 436 mss->referenced += ptent_size; 437 mapcount = page_mapcount(page); 438 if (mapcount >= 2) { 439 if (pte_dirty(ptent) || PageDirty(page)) 440 mss->shared_dirty += ptent_size; 441 else 442 mss->shared_clean += ptent_size; 443 mss->pss += (ptent_size << PSS_SHIFT) / mapcount; 444 } else { 445 if (pte_dirty(ptent) || PageDirty(page)) 446 mss->private_dirty += ptent_size; 447 else 448 mss->private_clean += ptent_size; 449 mss->pss += (ptent_size << PSS_SHIFT); 450 } 451 } 452 453 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 454 struct mm_walk *walk) 455 { 456 struct mem_size_stats *mss = walk->private; 457 struct vm_area_struct *vma = mss->vma; 458 pte_t *pte; 459 spinlock_t *ptl; 460 461 if (pmd_trans_huge_lock(pmd, vma) == 1) { 462 smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk); 463 spin_unlock(&walk->mm->page_table_lock); 464 mss->anonymous_thp += HPAGE_PMD_SIZE; 465 return 0; 466 } 467 468 if (pmd_trans_unstable(pmd)) 469 return 0; 470 /* 471 * The mmap_sem held all the way back in m_start() is what 472 * keeps khugepaged out of here and from collapsing things 473 * in here. 474 */ 475 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 476 for (; addr != end; pte++, addr += PAGE_SIZE) 477 smaps_pte_entry(*pte, addr, PAGE_SIZE, walk); 478 pte_unmap_unlock(pte - 1, ptl); 479 cond_resched(); 480 return 0; 481 } 482 483 static int show_smap(struct seq_file *m, void *v, int is_pid) 484 { 485 struct proc_maps_private *priv = m->private; 486 struct task_struct *task = priv->task; 487 struct vm_area_struct *vma = v; 488 struct mem_size_stats mss; 489 struct mm_walk smaps_walk = { 490 .pmd_entry = smaps_pte_range, 491 .mm = vma->vm_mm, 492 .private = &mss, 493 }; 494 495 memset(&mss, 0, sizeof mss); 496 mss.vma = vma; 497 /* mmap_sem is held in m_start */ 498 if (vma->vm_mm && !is_vm_hugetlb_page(vma)) 499 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk); 500 501 show_map_vma(m, vma, is_pid); 502 503 seq_printf(m, 504 "Size: %8lu kB\n" 505 "Rss: %8lu kB\n" 506 "Pss: %8lu kB\n" 507 "Shared_Clean: %8lu kB\n" 508 "Shared_Dirty: %8lu kB\n" 509 "Private_Clean: %8lu kB\n" 510 "Private_Dirty: %8lu kB\n" 511 "Referenced: %8lu kB\n" 512 "Anonymous: %8lu kB\n" 513 "AnonHugePages: %8lu kB\n" 514 "Swap: %8lu kB\n" 515 "KernelPageSize: %8lu kB\n" 516 "MMUPageSize: %8lu kB\n" 517 "Locked: %8lu kB\n", 518 (vma->vm_end - vma->vm_start) >> 10, 519 mss.resident >> 10, 520 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)), 521 mss.shared_clean >> 10, 522 mss.shared_dirty >> 10, 523 mss.private_clean >> 10, 524 mss.private_dirty >> 10, 525 mss.referenced >> 10, 526 mss.anonymous >> 10, 527 mss.anonymous_thp >> 10, 528 mss.swap >> 10, 529 vma_kernel_pagesize(vma) >> 10, 530 vma_mmu_pagesize(vma) >> 10, 531 (vma->vm_flags & VM_LOCKED) ? 532 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0); 533 534 if (vma->vm_flags & VM_NONLINEAR) 535 seq_printf(m, "Nonlinear: %8lu kB\n", 536 mss.nonlinear >> 10); 537 538 if (m->count < m->size) /* vma is copied successfully */ 539 m->version = (vma != get_gate_vma(task->mm)) 540 ? vma->vm_start : 0; 541 return 0; 542 } 543 544 static int show_pid_smap(struct seq_file *m, void *v) 545 { 546 return show_smap(m, v, 1); 547 } 548 549 static int show_tid_smap(struct seq_file *m, void *v) 550 { 551 return show_smap(m, v, 0); 552 } 553 554 static const struct seq_operations proc_pid_smaps_op = { 555 .start = m_start, 556 .next = m_next, 557 .stop = m_stop, 558 .show = show_pid_smap 559 }; 560 561 static const struct seq_operations proc_tid_smaps_op = { 562 .start = m_start, 563 .next = m_next, 564 .stop = m_stop, 565 .show = show_tid_smap 566 }; 567 568 static int pid_smaps_open(struct inode *inode, struct file *file) 569 { 570 return do_maps_open(inode, file, &proc_pid_smaps_op); 571 } 572 573 static int tid_smaps_open(struct inode *inode, struct file *file) 574 { 575 return do_maps_open(inode, file, &proc_tid_smaps_op); 576 } 577 578 const struct file_operations proc_pid_smaps_operations = { 579 .open = pid_smaps_open, 580 .read = seq_read, 581 .llseek = seq_lseek, 582 .release = seq_release_private, 583 }; 584 585 const struct file_operations proc_tid_smaps_operations = { 586 .open = tid_smaps_open, 587 .read = seq_read, 588 .llseek = seq_lseek, 589 .release = seq_release_private, 590 }; 591 592 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 593 unsigned long end, struct mm_walk *walk) 594 { 595 struct vm_area_struct *vma = walk->private; 596 pte_t *pte, ptent; 597 spinlock_t *ptl; 598 struct page *page; 599 600 split_huge_page_pmd(walk->mm, pmd); 601 if (pmd_trans_unstable(pmd)) 602 return 0; 603 604 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 605 for (; addr != end; pte++, addr += PAGE_SIZE) { 606 ptent = *pte; 607 if (!pte_present(ptent)) 608 continue; 609 610 page = vm_normal_page(vma, addr, ptent); 611 if (!page) 612 continue; 613 614 /* Clear accessed and referenced bits. */ 615 ptep_test_and_clear_young(vma, addr, pte); 616 ClearPageReferenced(page); 617 } 618 pte_unmap_unlock(pte - 1, ptl); 619 cond_resched(); 620 return 0; 621 } 622 623 #define CLEAR_REFS_ALL 1 624 #define CLEAR_REFS_ANON 2 625 #define CLEAR_REFS_MAPPED 3 626 627 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 628 size_t count, loff_t *ppos) 629 { 630 struct task_struct *task; 631 char buffer[PROC_NUMBUF]; 632 struct mm_struct *mm; 633 struct vm_area_struct *vma; 634 int type; 635 int rv; 636 637 memset(buffer, 0, sizeof(buffer)); 638 if (count > sizeof(buffer) - 1) 639 count = sizeof(buffer) - 1; 640 if (copy_from_user(buffer, buf, count)) 641 return -EFAULT; 642 rv = kstrtoint(strstrip(buffer), 10, &type); 643 if (rv < 0) 644 return rv; 645 if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED) 646 return -EINVAL; 647 task = get_proc_task(file->f_path.dentry->d_inode); 648 if (!task) 649 return -ESRCH; 650 mm = get_task_mm(task); 651 if (mm) { 652 struct mm_walk clear_refs_walk = { 653 .pmd_entry = clear_refs_pte_range, 654 .mm = mm, 655 }; 656 down_read(&mm->mmap_sem); 657 for (vma = mm->mmap; vma; vma = vma->vm_next) { 658 clear_refs_walk.private = vma; 659 if (is_vm_hugetlb_page(vma)) 660 continue; 661 /* 662 * Writing 1 to /proc/pid/clear_refs affects all pages. 663 * 664 * Writing 2 to /proc/pid/clear_refs only affects 665 * Anonymous pages. 666 * 667 * Writing 3 to /proc/pid/clear_refs only affects file 668 * mapped pages. 669 */ 670 if (type == CLEAR_REFS_ANON && vma->vm_file) 671 continue; 672 if (type == CLEAR_REFS_MAPPED && !vma->vm_file) 673 continue; 674 walk_page_range(vma->vm_start, vma->vm_end, 675 &clear_refs_walk); 676 } 677 flush_tlb_mm(mm); 678 up_read(&mm->mmap_sem); 679 mmput(mm); 680 } 681 put_task_struct(task); 682 683 return count; 684 } 685 686 const struct file_operations proc_clear_refs_operations = { 687 .write = clear_refs_write, 688 .llseek = noop_llseek, 689 }; 690 691 typedef struct { 692 u64 pme; 693 } pagemap_entry_t; 694 695 struct pagemapread { 696 int pos, len; 697 pagemap_entry_t *buffer; 698 }; 699 700 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 701 #define PAGEMAP_WALK_MASK (PMD_MASK) 702 703 #define PM_ENTRY_BYTES sizeof(u64) 704 #define PM_STATUS_BITS 3 705 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) 706 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) 707 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) 708 #define PM_PSHIFT_BITS 6 709 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) 710 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) 711 #define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) 712 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) 713 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) 714 715 #define PM_PRESENT PM_STATUS(4LL) 716 #define PM_SWAP PM_STATUS(2LL) 717 #define PM_FILE PM_STATUS(1LL) 718 #define PM_NOT_PRESENT PM_PSHIFT(PAGE_SHIFT) 719 #define PM_END_OF_BUFFER 1 720 721 static inline pagemap_entry_t make_pme(u64 val) 722 { 723 return (pagemap_entry_t) { .pme = val }; 724 } 725 726 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 727 struct pagemapread *pm) 728 { 729 pm->buffer[pm->pos++] = *pme; 730 if (pm->pos >= pm->len) 731 return PM_END_OF_BUFFER; 732 return 0; 733 } 734 735 static int pagemap_pte_hole(unsigned long start, unsigned long end, 736 struct mm_walk *walk) 737 { 738 struct pagemapread *pm = walk->private; 739 unsigned long addr; 740 int err = 0; 741 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT); 742 743 for (addr = start; addr < end; addr += PAGE_SIZE) { 744 err = add_to_pagemap(addr, &pme, pm); 745 if (err) 746 break; 747 } 748 return err; 749 } 750 751 static void pte_to_pagemap_entry(pagemap_entry_t *pme, 752 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 753 { 754 u64 frame, flags; 755 struct page *page = NULL; 756 757 if (pte_present(pte)) { 758 frame = pte_pfn(pte); 759 flags = PM_PRESENT; 760 page = vm_normal_page(vma, addr, pte); 761 } else if (is_swap_pte(pte)) { 762 swp_entry_t entry = pte_to_swp_entry(pte); 763 764 frame = swp_type(entry) | 765 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 766 flags = PM_SWAP; 767 if (is_migration_entry(entry)) 768 page = migration_entry_to_page(entry); 769 } else { 770 *pme = make_pme(PM_NOT_PRESENT); 771 return; 772 } 773 774 if (page && !PageAnon(page)) 775 flags |= PM_FILE; 776 777 *pme = make_pme(PM_PFRAME(frame) | PM_PSHIFT(PAGE_SHIFT) | flags); 778 } 779 780 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 781 static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, 782 pmd_t pmd, int offset) 783 { 784 /* 785 * Currently pmd for thp is always present because thp can not be 786 * swapped-out, migrated, or HWPOISONed (split in such cases instead.) 787 * This if-check is just to prepare for future implementation. 788 */ 789 if (pmd_present(pmd)) 790 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset) 791 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT); 792 else 793 *pme = make_pme(PM_NOT_PRESENT); 794 } 795 #else 796 static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, 797 pmd_t pmd, int offset) 798 { 799 } 800 #endif 801 802 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 803 struct mm_walk *walk) 804 { 805 struct vm_area_struct *vma; 806 struct pagemapread *pm = walk->private; 807 pte_t *pte; 808 int err = 0; 809 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT); 810 811 /* find the first VMA at or above 'addr' */ 812 vma = find_vma(walk->mm, addr); 813 if (vma && pmd_trans_huge_lock(pmd, vma) == 1) { 814 for (; addr != end; addr += PAGE_SIZE) { 815 unsigned long offset; 816 817 offset = (addr & ~PAGEMAP_WALK_MASK) >> 818 PAGE_SHIFT; 819 thp_pmd_to_pagemap_entry(&pme, *pmd, offset); 820 err = add_to_pagemap(addr, &pme, pm); 821 if (err) 822 break; 823 } 824 spin_unlock(&walk->mm->page_table_lock); 825 return err; 826 } 827 828 if (pmd_trans_unstable(pmd)) 829 return 0; 830 for (; addr != end; addr += PAGE_SIZE) { 831 832 /* check to see if we've left 'vma' behind 833 * and need a new, higher one */ 834 if (vma && (addr >= vma->vm_end)) { 835 vma = find_vma(walk->mm, addr); 836 pme = make_pme(PM_NOT_PRESENT); 837 } 838 839 /* check that 'vma' actually covers this address, 840 * and that it isn't a huge page vma */ 841 if (vma && (vma->vm_start <= addr) && 842 !is_vm_hugetlb_page(vma)) { 843 pte = pte_offset_map(pmd, addr); 844 pte_to_pagemap_entry(&pme, vma, addr, *pte); 845 /* unmap before userspace copy */ 846 pte_unmap(pte); 847 } 848 err = add_to_pagemap(addr, &pme, pm); 849 if (err) 850 return err; 851 } 852 853 cond_resched(); 854 855 return err; 856 } 857 858 #ifdef CONFIG_HUGETLB_PAGE 859 static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, 860 pte_t pte, int offset) 861 { 862 if (pte_present(pte)) 863 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) 864 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT); 865 else 866 *pme = make_pme(PM_NOT_PRESENT); 867 } 868 869 /* This function walks within one hugetlb entry in the single call */ 870 static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask, 871 unsigned long addr, unsigned long end, 872 struct mm_walk *walk) 873 { 874 struct pagemapread *pm = walk->private; 875 int err = 0; 876 pagemap_entry_t pme; 877 878 for (; addr != end; addr += PAGE_SIZE) { 879 int offset = (addr & ~hmask) >> PAGE_SHIFT; 880 huge_pte_to_pagemap_entry(&pme, *pte, offset); 881 err = add_to_pagemap(addr, &pme, pm); 882 if (err) 883 return err; 884 } 885 886 cond_resched(); 887 888 return err; 889 } 890 #endif /* HUGETLB_PAGE */ 891 892 /* 893 * /proc/pid/pagemap - an array mapping virtual pages to pfns 894 * 895 * For each page in the address space, this file contains one 64-bit entry 896 * consisting of the following: 897 * 898 * Bits 0-54 page frame number (PFN) if present 899 * Bits 0-4 swap type if swapped 900 * Bits 5-54 swap offset if swapped 901 * Bits 55-60 page shift (page size = 1<<page shift) 902 * Bit 61 page is file-page or shared-anon 903 * Bit 62 page swapped 904 * Bit 63 page present 905 * 906 * If the page is not present but in swap, then the PFN contains an 907 * encoding of the swap file number and the page's offset into the 908 * swap. Unmapped pages return a null PFN. This allows determining 909 * precisely which pages are mapped (or in swap) and comparing mapped 910 * pages between processes. 911 * 912 * Efficient users of this interface will use /proc/pid/maps to 913 * determine which areas of memory are actually mapped and llseek to 914 * skip over unmapped regions. 915 */ 916 static ssize_t pagemap_read(struct file *file, char __user *buf, 917 size_t count, loff_t *ppos) 918 { 919 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 920 struct mm_struct *mm; 921 struct pagemapread pm; 922 int ret = -ESRCH; 923 struct mm_walk pagemap_walk = {}; 924 unsigned long src; 925 unsigned long svpfn; 926 unsigned long start_vaddr; 927 unsigned long end_vaddr; 928 int copied = 0; 929 930 if (!task) 931 goto out; 932 933 ret = -EINVAL; 934 /* file position must be aligned */ 935 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 936 goto out_task; 937 938 ret = 0; 939 if (!count) 940 goto out_task; 941 942 pm.len = PM_ENTRY_BYTES * (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 943 pm.buffer = kmalloc(pm.len, GFP_TEMPORARY); 944 ret = -ENOMEM; 945 if (!pm.buffer) 946 goto out_task; 947 948 mm = mm_access(task, PTRACE_MODE_READ); 949 ret = PTR_ERR(mm); 950 if (!mm || IS_ERR(mm)) 951 goto out_free; 952 953 pagemap_walk.pmd_entry = pagemap_pte_range; 954 pagemap_walk.pte_hole = pagemap_pte_hole; 955 #ifdef CONFIG_HUGETLB_PAGE 956 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 957 #endif 958 pagemap_walk.mm = mm; 959 pagemap_walk.private = ± 960 961 src = *ppos; 962 svpfn = src / PM_ENTRY_BYTES; 963 start_vaddr = svpfn << PAGE_SHIFT; 964 end_vaddr = TASK_SIZE_OF(task); 965 966 /* watch out for wraparound */ 967 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT) 968 start_vaddr = end_vaddr; 969 970 /* 971 * The odds are that this will stop walking way 972 * before end_vaddr, because the length of the 973 * user buffer is tracked in "pm", and the walk 974 * will stop when we hit the end of the buffer. 975 */ 976 ret = 0; 977 while (count && (start_vaddr < end_vaddr)) { 978 int len; 979 unsigned long end; 980 981 pm.pos = 0; 982 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 983 /* overflow ? */ 984 if (end < start_vaddr || end > end_vaddr) 985 end = end_vaddr; 986 down_read(&mm->mmap_sem); 987 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 988 up_read(&mm->mmap_sem); 989 start_vaddr = end; 990 991 len = min(count, PM_ENTRY_BYTES * pm.pos); 992 if (copy_to_user(buf, pm.buffer, len)) { 993 ret = -EFAULT; 994 goto out_mm; 995 } 996 copied += len; 997 buf += len; 998 count -= len; 999 } 1000 *ppos += copied; 1001 if (!ret || ret == PM_END_OF_BUFFER) 1002 ret = copied; 1003 1004 out_mm: 1005 mmput(mm); 1006 out_free: 1007 kfree(pm.buffer); 1008 out_task: 1009 put_task_struct(task); 1010 out: 1011 return ret; 1012 } 1013 1014 const struct file_operations proc_pagemap_operations = { 1015 .llseek = mem_lseek, /* borrow this */ 1016 .read = pagemap_read, 1017 }; 1018 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1019 1020 #ifdef CONFIG_NUMA 1021 1022 struct numa_maps { 1023 struct vm_area_struct *vma; 1024 unsigned long pages; 1025 unsigned long anon; 1026 unsigned long active; 1027 unsigned long writeback; 1028 unsigned long mapcount_max; 1029 unsigned long dirty; 1030 unsigned long swapcache; 1031 unsigned long node[MAX_NUMNODES]; 1032 }; 1033 1034 struct numa_maps_private { 1035 struct proc_maps_private proc_maps; 1036 struct numa_maps md; 1037 }; 1038 1039 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1040 unsigned long nr_pages) 1041 { 1042 int count = page_mapcount(page); 1043 1044 md->pages += nr_pages; 1045 if (pte_dirty || PageDirty(page)) 1046 md->dirty += nr_pages; 1047 1048 if (PageSwapCache(page)) 1049 md->swapcache += nr_pages; 1050 1051 if (PageActive(page) || PageUnevictable(page)) 1052 md->active += nr_pages; 1053 1054 if (PageWriteback(page)) 1055 md->writeback += nr_pages; 1056 1057 if (PageAnon(page)) 1058 md->anon += nr_pages; 1059 1060 if (count > md->mapcount_max) 1061 md->mapcount_max = count; 1062 1063 md->node[page_to_nid(page)] += nr_pages; 1064 } 1065 1066 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1067 unsigned long addr) 1068 { 1069 struct page *page; 1070 int nid; 1071 1072 if (!pte_present(pte)) 1073 return NULL; 1074 1075 page = vm_normal_page(vma, addr, pte); 1076 if (!page) 1077 return NULL; 1078 1079 if (PageReserved(page)) 1080 return NULL; 1081 1082 nid = page_to_nid(page); 1083 if (!node_isset(nid, node_states[N_HIGH_MEMORY])) 1084 return NULL; 1085 1086 return page; 1087 } 1088 1089 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1090 unsigned long end, struct mm_walk *walk) 1091 { 1092 struct numa_maps *md; 1093 spinlock_t *ptl; 1094 pte_t *orig_pte; 1095 pte_t *pte; 1096 1097 md = walk->private; 1098 1099 if (pmd_trans_huge_lock(pmd, md->vma) == 1) { 1100 pte_t huge_pte = *(pte_t *)pmd; 1101 struct page *page; 1102 1103 page = can_gather_numa_stats(huge_pte, md->vma, addr); 1104 if (page) 1105 gather_stats(page, md, pte_dirty(huge_pte), 1106 HPAGE_PMD_SIZE/PAGE_SIZE); 1107 spin_unlock(&walk->mm->page_table_lock); 1108 return 0; 1109 } 1110 1111 if (pmd_trans_unstable(pmd)) 1112 return 0; 1113 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1114 do { 1115 struct page *page = can_gather_numa_stats(*pte, md->vma, addr); 1116 if (!page) 1117 continue; 1118 gather_stats(page, md, pte_dirty(*pte), 1); 1119 1120 } while (pte++, addr += PAGE_SIZE, addr != end); 1121 pte_unmap_unlock(orig_pte, ptl); 1122 return 0; 1123 } 1124 #ifdef CONFIG_HUGETLB_PAGE 1125 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1126 unsigned long addr, unsigned long end, struct mm_walk *walk) 1127 { 1128 struct numa_maps *md; 1129 struct page *page; 1130 1131 if (pte_none(*pte)) 1132 return 0; 1133 1134 page = pte_page(*pte); 1135 if (!page) 1136 return 0; 1137 1138 md = walk->private; 1139 gather_stats(page, md, pte_dirty(*pte), 1); 1140 return 0; 1141 } 1142 1143 #else 1144 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1145 unsigned long addr, unsigned long end, struct mm_walk *walk) 1146 { 1147 return 0; 1148 } 1149 #endif 1150 1151 /* 1152 * Display pages allocated per node and memory policy via /proc. 1153 */ 1154 static int show_numa_map(struct seq_file *m, void *v, int is_pid) 1155 { 1156 struct numa_maps_private *numa_priv = m->private; 1157 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1158 struct vm_area_struct *vma = v; 1159 struct numa_maps *md = &numa_priv->md; 1160 struct file *file = vma->vm_file; 1161 struct mm_struct *mm = vma->vm_mm; 1162 struct mm_walk walk = {}; 1163 struct mempolicy *pol; 1164 int n; 1165 char buffer[50]; 1166 1167 if (!mm) 1168 return 0; 1169 1170 /* Ensure we start with an empty set of numa_maps statistics. */ 1171 memset(md, 0, sizeof(*md)); 1172 1173 md->vma = vma; 1174 1175 walk.hugetlb_entry = gather_hugetbl_stats; 1176 walk.pmd_entry = gather_pte_stats; 1177 walk.private = md; 1178 walk.mm = mm; 1179 1180 pol = get_vma_policy(proc_priv->task, vma, vma->vm_start); 1181 mpol_to_str(buffer, sizeof(buffer), pol, 0); 1182 mpol_cond_put(pol); 1183 1184 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1185 1186 if (file) { 1187 seq_printf(m, " file="); 1188 seq_path(m, &file->f_path, "\n\t= "); 1189 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1190 seq_printf(m, " heap"); 1191 } else { 1192 pid_t tid = vm_is_stack(proc_priv->task, vma, is_pid); 1193 if (tid != 0) { 1194 /* 1195 * Thread stack in /proc/PID/task/TID/maps or 1196 * the main process stack. 1197 */ 1198 if (!is_pid || (vma->vm_start <= mm->start_stack && 1199 vma->vm_end >= mm->start_stack)) 1200 seq_printf(m, " stack"); 1201 else 1202 seq_printf(m, " stack:%d", tid); 1203 } 1204 } 1205 1206 if (is_vm_hugetlb_page(vma)) 1207 seq_printf(m, " huge"); 1208 1209 walk_page_range(vma->vm_start, vma->vm_end, &walk); 1210 1211 if (!md->pages) 1212 goto out; 1213 1214 if (md->anon) 1215 seq_printf(m, " anon=%lu", md->anon); 1216 1217 if (md->dirty) 1218 seq_printf(m, " dirty=%lu", md->dirty); 1219 1220 if (md->pages != md->anon && md->pages != md->dirty) 1221 seq_printf(m, " mapped=%lu", md->pages); 1222 1223 if (md->mapcount_max > 1) 1224 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1225 1226 if (md->swapcache) 1227 seq_printf(m, " swapcache=%lu", md->swapcache); 1228 1229 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1230 seq_printf(m, " active=%lu", md->active); 1231 1232 if (md->writeback) 1233 seq_printf(m, " writeback=%lu", md->writeback); 1234 1235 for_each_node_state(n, N_HIGH_MEMORY) 1236 if (md->node[n]) 1237 seq_printf(m, " N%d=%lu", n, md->node[n]); 1238 out: 1239 seq_putc(m, '\n'); 1240 1241 if (m->count < m->size) 1242 m->version = (vma != proc_priv->tail_vma) ? vma->vm_start : 0; 1243 return 0; 1244 } 1245 1246 static int show_pid_numa_map(struct seq_file *m, void *v) 1247 { 1248 return show_numa_map(m, v, 1); 1249 } 1250 1251 static int show_tid_numa_map(struct seq_file *m, void *v) 1252 { 1253 return show_numa_map(m, v, 0); 1254 } 1255 1256 static const struct seq_operations proc_pid_numa_maps_op = { 1257 .start = m_start, 1258 .next = m_next, 1259 .stop = m_stop, 1260 .show = show_pid_numa_map, 1261 }; 1262 1263 static const struct seq_operations proc_tid_numa_maps_op = { 1264 .start = m_start, 1265 .next = m_next, 1266 .stop = m_stop, 1267 .show = show_tid_numa_map, 1268 }; 1269 1270 static int numa_maps_open(struct inode *inode, struct file *file, 1271 const struct seq_operations *ops) 1272 { 1273 struct numa_maps_private *priv; 1274 int ret = -ENOMEM; 1275 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 1276 if (priv) { 1277 priv->proc_maps.pid = proc_pid(inode); 1278 ret = seq_open(file, ops); 1279 if (!ret) { 1280 struct seq_file *m = file->private_data; 1281 m->private = priv; 1282 } else { 1283 kfree(priv); 1284 } 1285 } 1286 return ret; 1287 } 1288 1289 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1290 { 1291 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1292 } 1293 1294 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1295 { 1296 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1297 } 1298 1299 const struct file_operations proc_pid_numa_maps_operations = { 1300 .open = pid_numa_maps_open, 1301 .read = seq_read, 1302 .llseek = seq_lseek, 1303 .release = seq_release_private, 1304 }; 1305 1306 const struct file_operations proc_tid_numa_maps_operations = { 1307 .open = tid_numa_maps_open, 1308 .read = seq_read, 1309 .llseek = seq_lseek, 1310 .release = seq_release_private, 1311 }; 1312 #endif /* CONFIG_NUMA */ 1313