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_for_maps(priv->task); 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 u64 pss; 397 }; 398 399 400 static void smaps_pte_entry(pte_t ptent, unsigned long addr, 401 unsigned long ptent_size, struct mm_walk *walk) 402 { 403 struct mem_size_stats *mss = walk->private; 404 struct vm_area_struct *vma = mss->vma; 405 struct page *page; 406 int mapcount; 407 408 if (is_swap_pte(ptent)) { 409 mss->swap += ptent_size; 410 return; 411 } 412 413 if (!pte_present(ptent)) 414 return; 415 416 page = vm_normal_page(vma, addr, ptent); 417 if (!page) 418 return; 419 420 if (PageAnon(page)) 421 mss->anonymous += ptent_size; 422 423 mss->resident += ptent_size; 424 /* Accumulate the size in pages that have been accessed. */ 425 if (pte_young(ptent) || PageReferenced(page)) 426 mss->referenced += ptent_size; 427 mapcount = page_mapcount(page); 428 if (mapcount >= 2) { 429 if (pte_dirty(ptent) || PageDirty(page)) 430 mss->shared_dirty += ptent_size; 431 else 432 mss->shared_clean += ptent_size; 433 mss->pss += (ptent_size << PSS_SHIFT) / mapcount; 434 } else { 435 if (pte_dirty(ptent) || PageDirty(page)) 436 mss->private_dirty += ptent_size; 437 else 438 mss->private_clean += ptent_size; 439 mss->pss += (ptent_size << PSS_SHIFT); 440 } 441 } 442 443 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 444 struct mm_walk *walk) 445 { 446 struct mem_size_stats *mss = walk->private; 447 struct vm_area_struct *vma = mss->vma; 448 pte_t *pte; 449 spinlock_t *ptl; 450 451 if (pmd_trans_huge_lock(pmd, vma) == 1) { 452 smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk); 453 spin_unlock(&walk->mm->page_table_lock); 454 mss->anonymous_thp += HPAGE_PMD_SIZE; 455 return 0; 456 } 457 458 if (pmd_trans_unstable(pmd)) 459 return 0; 460 /* 461 * The mmap_sem held all the way back in m_start() is what 462 * keeps khugepaged out of here and from collapsing things 463 * in here. 464 */ 465 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 466 for (; addr != end; pte++, addr += PAGE_SIZE) 467 smaps_pte_entry(*pte, addr, PAGE_SIZE, walk); 468 pte_unmap_unlock(pte - 1, ptl); 469 cond_resched(); 470 return 0; 471 } 472 473 static int show_smap(struct seq_file *m, void *v, int is_pid) 474 { 475 struct proc_maps_private *priv = m->private; 476 struct task_struct *task = priv->task; 477 struct vm_area_struct *vma = v; 478 struct mem_size_stats mss; 479 struct mm_walk smaps_walk = { 480 .pmd_entry = smaps_pte_range, 481 .mm = vma->vm_mm, 482 .private = &mss, 483 }; 484 485 memset(&mss, 0, sizeof mss); 486 mss.vma = vma; 487 /* mmap_sem is held in m_start */ 488 if (vma->vm_mm && !is_vm_hugetlb_page(vma)) 489 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk); 490 491 show_map_vma(m, vma, is_pid); 492 493 seq_printf(m, 494 "Size: %8lu kB\n" 495 "Rss: %8lu kB\n" 496 "Pss: %8lu kB\n" 497 "Shared_Clean: %8lu kB\n" 498 "Shared_Dirty: %8lu kB\n" 499 "Private_Clean: %8lu kB\n" 500 "Private_Dirty: %8lu kB\n" 501 "Referenced: %8lu kB\n" 502 "Anonymous: %8lu kB\n" 503 "AnonHugePages: %8lu kB\n" 504 "Swap: %8lu kB\n" 505 "KernelPageSize: %8lu kB\n" 506 "MMUPageSize: %8lu kB\n" 507 "Locked: %8lu kB\n", 508 (vma->vm_end - vma->vm_start) >> 10, 509 mss.resident >> 10, 510 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)), 511 mss.shared_clean >> 10, 512 mss.shared_dirty >> 10, 513 mss.private_clean >> 10, 514 mss.private_dirty >> 10, 515 mss.referenced >> 10, 516 mss.anonymous >> 10, 517 mss.anonymous_thp >> 10, 518 mss.swap >> 10, 519 vma_kernel_pagesize(vma) >> 10, 520 vma_mmu_pagesize(vma) >> 10, 521 (vma->vm_flags & VM_LOCKED) ? 522 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0); 523 524 if (m->count < m->size) /* vma is copied successfully */ 525 m->version = (vma != get_gate_vma(task->mm)) 526 ? vma->vm_start : 0; 527 return 0; 528 } 529 530 static int show_pid_smap(struct seq_file *m, void *v) 531 { 532 return show_smap(m, v, 1); 533 } 534 535 static int show_tid_smap(struct seq_file *m, void *v) 536 { 537 return show_smap(m, v, 0); 538 } 539 540 static const struct seq_operations proc_pid_smaps_op = { 541 .start = m_start, 542 .next = m_next, 543 .stop = m_stop, 544 .show = show_pid_smap 545 }; 546 547 static const struct seq_operations proc_tid_smaps_op = { 548 .start = m_start, 549 .next = m_next, 550 .stop = m_stop, 551 .show = show_tid_smap 552 }; 553 554 static int pid_smaps_open(struct inode *inode, struct file *file) 555 { 556 return do_maps_open(inode, file, &proc_pid_smaps_op); 557 } 558 559 static int tid_smaps_open(struct inode *inode, struct file *file) 560 { 561 return do_maps_open(inode, file, &proc_tid_smaps_op); 562 } 563 564 const struct file_operations proc_pid_smaps_operations = { 565 .open = pid_smaps_open, 566 .read = seq_read, 567 .llseek = seq_lseek, 568 .release = seq_release_private, 569 }; 570 571 const struct file_operations proc_tid_smaps_operations = { 572 .open = tid_smaps_open, 573 .read = seq_read, 574 .llseek = seq_lseek, 575 .release = seq_release_private, 576 }; 577 578 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 579 unsigned long end, struct mm_walk *walk) 580 { 581 struct vm_area_struct *vma = walk->private; 582 pte_t *pte, ptent; 583 spinlock_t *ptl; 584 struct page *page; 585 586 split_huge_page_pmd(walk->mm, pmd); 587 if (pmd_trans_unstable(pmd)) 588 return 0; 589 590 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 591 for (; addr != end; pte++, addr += PAGE_SIZE) { 592 ptent = *pte; 593 if (!pte_present(ptent)) 594 continue; 595 596 page = vm_normal_page(vma, addr, ptent); 597 if (!page) 598 continue; 599 600 /* Clear accessed and referenced bits. */ 601 ptep_test_and_clear_young(vma, addr, pte); 602 ClearPageReferenced(page); 603 } 604 pte_unmap_unlock(pte - 1, ptl); 605 cond_resched(); 606 return 0; 607 } 608 609 #define CLEAR_REFS_ALL 1 610 #define CLEAR_REFS_ANON 2 611 #define CLEAR_REFS_MAPPED 3 612 613 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 614 size_t count, loff_t *ppos) 615 { 616 struct task_struct *task; 617 char buffer[PROC_NUMBUF]; 618 struct mm_struct *mm; 619 struct vm_area_struct *vma; 620 int type; 621 int rv; 622 623 memset(buffer, 0, sizeof(buffer)); 624 if (count > sizeof(buffer) - 1) 625 count = sizeof(buffer) - 1; 626 if (copy_from_user(buffer, buf, count)) 627 return -EFAULT; 628 rv = kstrtoint(strstrip(buffer), 10, &type); 629 if (rv < 0) 630 return rv; 631 if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED) 632 return -EINVAL; 633 task = get_proc_task(file->f_path.dentry->d_inode); 634 if (!task) 635 return -ESRCH; 636 mm = get_task_mm(task); 637 if (mm) { 638 struct mm_walk clear_refs_walk = { 639 .pmd_entry = clear_refs_pte_range, 640 .mm = mm, 641 }; 642 down_read(&mm->mmap_sem); 643 for (vma = mm->mmap; vma; vma = vma->vm_next) { 644 clear_refs_walk.private = vma; 645 if (is_vm_hugetlb_page(vma)) 646 continue; 647 /* 648 * Writing 1 to /proc/pid/clear_refs affects all pages. 649 * 650 * Writing 2 to /proc/pid/clear_refs only affects 651 * Anonymous pages. 652 * 653 * Writing 3 to /proc/pid/clear_refs only affects file 654 * mapped pages. 655 */ 656 if (type == CLEAR_REFS_ANON && vma->vm_file) 657 continue; 658 if (type == CLEAR_REFS_MAPPED && !vma->vm_file) 659 continue; 660 walk_page_range(vma->vm_start, vma->vm_end, 661 &clear_refs_walk); 662 } 663 flush_tlb_mm(mm); 664 up_read(&mm->mmap_sem); 665 mmput(mm); 666 } 667 put_task_struct(task); 668 669 return count; 670 } 671 672 const struct file_operations proc_clear_refs_operations = { 673 .write = clear_refs_write, 674 .llseek = noop_llseek, 675 }; 676 677 typedef struct { 678 u64 pme; 679 } pagemap_entry_t; 680 681 struct pagemapread { 682 int pos, len; 683 pagemap_entry_t *buffer; 684 }; 685 686 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 687 #define PAGEMAP_WALK_MASK (PMD_MASK) 688 689 #define PM_ENTRY_BYTES sizeof(u64) 690 #define PM_STATUS_BITS 3 691 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) 692 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) 693 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) 694 #define PM_PSHIFT_BITS 6 695 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) 696 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) 697 #define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) 698 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) 699 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) 700 701 #define PM_PRESENT PM_STATUS(4LL) 702 #define PM_SWAP PM_STATUS(2LL) 703 #define PM_NOT_PRESENT PM_PSHIFT(PAGE_SHIFT) 704 #define PM_END_OF_BUFFER 1 705 706 static inline pagemap_entry_t make_pme(u64 val) 707 { 708 return (pagemap_entry_t) { .pme = val }; 709 } 710 711 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 712 struct pagemapread *pm) 713 { 714 pm->buffer[pm->pos++] = *pme; 715 if (pm->pos >= pm->len) 716 return PM_END_OF_BUFFER; 717 return 0; 718 } 719 720 static int pagemap_pte_hole(unsigned long start, unsigned long end, 721 struct mm_walk *walk) 722 { 723 struct pagemapread *pm = walk->private; 724 unsigned long addr; 725 int err = 0; 726 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT); 727 728 for (addr = start; addr < end; addr += PAGE_SIZE) { 729 err = add_to_pagemap(addr, &pme, pm); 730 if (err) 731 break; 732 } 733 return err; 734 } 735 736 static u64 swap_pte_to_pagemap_entry(pte_t pte) 737 { 738 swp_entry_t e = pte_to_swp_entry(pte); 739 return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT); 740 } 741 742 static void pte_to_pagemap_entry(pagemap_entry_t *pme, pte_t pte) 743 { 744 if (is_swap_pte(pte)) 745 *pme = make_pme(PM_PFRAME(swap_pte_to_pagemap_entry(pte)) 746 | PM_PSHIFT(PAGE_SHIFT) | PM_SWAP); 747 else if (pte_present(pte)) 748 *pme = make_pme(PM_PFRAME(pte_pfn(pte)) 749 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT); 750 } 751 752 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 753 static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, 754 pmd_t pmd, int offset) 755 { 756 /* 757 * Currently pmd for thp is always present because thp can not be 758 * swapped-out, migrated, or HWPOISONed (split in such cases instead.) 759 * This if-check is just to prepare for future implementation. 760 */ 761 if (pmd_present(pmd)) 762 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset) 763 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT); 764 } 765 #else 766 static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, 767 pmd_t pmd, int offset) 768 { 769 } 770 #endif 771 772 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 773 struct mm_walk *walk) 774 { 775 struct vm_area_struct *vma; 776 struct pagemapread *pm = walk->private; 777 pte_t *pte; 778 int err = 0; 779 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT); 780 781 /* find the first VMA at or above 'addr' */ 782 vma = find_vma(walk->mm, addr); 783 if (pmd_trans_huge_lock(pmd, vma) == 1) { 784 for (; addr != end; addr += PAGE_SIZE) { 785 unsigned long offset; 786 787 offset = (addr & ~PAGEMAP_WALK_MASK) >> 788 PAGE_SHIFT; 789 thp_pmd_to_pagemap_entry(&pme, *pmd, offset); 790 err = add_to_pagemap(addr, &pme, pm); 791 if (err) 792 break; 793 } 794 spin_unlock(&walk->mm->page_table_lock); 795 return err; 796 } 797 798 if (pmd_trans_unstable(pmd)) 799 return 0; 800 for (; addr != end; addr += PAGE_SIZE) { 801 802 /* check to see if we've left 'vma' behind 803 * and need a new, higher one */ 804 if (vma && (addr >= vma->vm_end)) 805 vma = find_vma(walk->mm, addr); 806 807 /* check that 'vma' actually covers this address, 808 * and that it isn't a huge page vma */ 809 if (vma && (vma->vm_start <= addr) && 810 !is_vm_hugetlb_page(vma)) { 811 pte = pte_offset_map(pmd, addr); 812 pte_to_pagemap_entry(&pme, *pte); 813 /* unmap before userspace copy */ 814 pte_unmap(pte); 815 } 816 err = add_to_pagemap(addr, &pme, pm); 817 if (err) 818 return err; 819 } 820 821 cond_resched(); 822 823 return err; 824 } 825 826 #ifdef CONFIG_HUGETLB_PAGE 827 static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, 828 pte_t pte, int offset) 829 { 830 if (pte_present(pte)) 831 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) 832 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT); 833 } 834 835 /* This function walks within one hugetlb entry in the single call */ 836 static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask, 837 unsigned long addr, unsigned long end, 838 struct mm_walk *walk) 839 { 840 struct pagemapread *pm = walk->private; 841 int err = 0; 842 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT); 843 844 for (; addr != end; addr += PAGE_SIZE) { 845 int offset = (addr & ~hmask) >> PAGE_SHIFT; 846 huge_pte_to_pagemap_entry(&pme, *pte, offset); 847 err = add_to_pagemap(addr, &pme, pm); 848 if (err) 849 return err; 850 } 851 852 cond_resched(); 853 854 return err; 855 } 856 #endif /* HUGETLB_PAGE */ 857 858 /* 859 * /proc/pid/pagemap - an array mapping virtual pages to pfns 860 * 861 * For each page in the address space, this file contains one 64-bit entry 862 * consisting of the following: 863 * 864 * Bits 0-55 page frame number (PFN) if present 865 * Bits 0-4 swap type if swapped 866 * Bits 5-55 swap offset if swapped 867 * Bits 55-60 page shift (page size = 1<<page shift) 868 * Bit 61 reserved for future use 869 * Bit 62 page swapped 870 * Bit 63 page present 871 * 872 * If the page is not present but in swap, then the PFN contains an 873 * encoding of the swap file number and the page's offset into the 874 * swap. Unmapped pages return a null PFN. This allows determining 875 * precisely which pages are mapped (or in swap) and comparing mapped 876 * pages between processes. 877 * 878 * Efficient users of this interface will use /proc/pid/maps to 879 * determine which areas of memory are actually mapped and llseek to 880 * skip over unmapped regions. 881 */ 882 static ssize_t pagemap_read(struct file *file, char __user *buf, 883 size_t count, loff_t *ppos) 884 { 885 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 886 struct mm_struct *mm; 887 struct pagemapread pm; 888 int ret = -ESRCH; 889 struct mm_walk pagemap_walk = {}; 890 unsigned long src; 891 unsigned long svpfn; 892 unsigned long start_vaddr; 893 unsigned long end_vaddr; 894 int copied = 0; 895 896 if (!task) 897 goto out; 898 899 ret = -EINVAL; 900 /* file position must be aligned */ 901 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 902 goto out_task; 903 904 ret = 0; 905 if (!count) 906 goto out_task; 907 908 pm.len = PM_ENTRY_BYTES * (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 909 pm.buffer = kmalloc(pm.len, GFP_TEMPORARY); 910 ret = -ENOMEM; 911 if (!pm.buffer) 912 goto out_task; 913 914 mm = mm_for_maps(task); 915 ret = PTR_ERR(mm); 916 if (!mm || IS_ERR(mm)) 917 goto out_free; 918 919 pagemap_walk.pmd_entry = pagemap_pte_range; 920 pagemap_walk.pte_hole = pagemap_pte_hole; 921 #ifdef CONFIG_HUGETLB_PAGE 922 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 923 #endif 924 pagemap_walk.mm = mm; 925 pagemap_walk.private = ± 926 927 src = *ppos; 928 svpfn = src / PM_ENTRY_BYTES; 929 start_vaddr = svpfn << PAGE_SHIFT; 930 end_vaddr = TASK_SIZE_OF(task); 931 932 /* watch out for wraparound */ 933 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT) 934 start_vaddr = end_vaddr; 935 936 /* 937 * The odds are that this will stop walking way 938 * before end_vaddr, because the length of the 939 * user buffer is tracked in "pm", and the walk 940 * will stop when we hit the end of the buffer. 941 */ 942 ret = 0; 943 while (count && (start_vaddr < end_vaddr)) { 944 int len; 945 unsigned long end; 946 947 pm.pos = 0; 948 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 949 /* overflow ? */ 950 if (end < start_vaddr || end > end_vaddr) 951 end = end_vaddr; 952 down_read(&mm->mmap_sem); 953 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 954 up_read(&mm->mmap_sem); 955 start_vaddr = end; 956 957 len = min(count, PM_ENTRY_BYTES * pm.pos); 958 if (copy_to_user(buf, pm.buffer, len)) { 959 ret = -EFAULT; 960 goto out_mm; 961 } 962 copied += len; 963 buf += len; 964 count -= len; 965 } 966 *ppos += copied; 967 if (!ret || ret == PM_END_OF_BUFFER) 968 ret = copied; 969 970 out_mm: 971 mmput(mm); 972 out_free: 973 kfree(pm.buffer); 974 out_task: 975 put_task_struct(task); 976 out: 977 return ret; 978 } 979 980 const struct file_operations proc_pagemap_operations = { 981 .llseek = mem_lseek, /* borrow this */ 982 .read = pagemap_read, 983 }; 984 #endif /* CONFIG_PROC_PAGE_MONITOR */ 985 986 #ifdef CONFIG_NUMA 987 988 struct numa_maps { 989 struct vm_area_struct *vma; 990 unsigned long pages; 991 unsigned long anon; 992 unsigned long active; 993 unsigned long writeback; 994 unsigned long mapcount_max; 995 unsigned long dirty; 996 unsigned long swapcache; 997 unsigned long node[MAX_NUMNODES]; 998 }; 999 1000 struct numa_maps_private { 1001 struct proc_maps_private proc_maps; 1002 struct numa_maps md; 1003 }; 1004 1005 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1006 unsigned long nr_pages) 1007 { 1008 int count = page_mapcount(page); 1009 1010 md->pages += nr_pages; 1011 if (pte_dirty || PageDirty(page)) 1012 md->dirty += nr_pages; 1013 1014 if (PageSwapCache(page)) 1015 md->swapcache += nr_pages; 1016 1017 if (PageActive(page) || PageUnevictable(page)) 1018 md->active += nr_pages; 1019 1020 if (PageWriteback(page)) 1021 md->writeback += nr_pages; 1022 1023 if (PageAnon(page)) 1024 md->anon += nr_pages; 1025 1026 if (count > md->mapcount_max) 1027 md->mapcount_max = count; 1028 1029 md->node[page_to_nid(page)] += nr_pages; 1030 } 1031 1032 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1033 unsigned long addr) 1034 { 1035 struct page *page; 1036 int nid; 1037 1038 if (!pte_present(pte)) 1039 return NULL; 1040 1041 page = vm_normal_page(vma, addr, pte); 1042 if (!page) 1043 return NULL; 1044 1045 if (PageReserved(page)) 1046 return NULL; 1047 1048 nid = page_to_nid(page); 1049 if (!node_isset(nid, node_states[N_HIGH_MEMORY])) 1050 return NULL; 1051 1052 return page; 1053 } 1054 1055 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1056 unsigned long end, struct mm_walk *walk) 1057 { 1058 struct numa_maps *md; 1059 spinlock_t *ptl; 1060 pte_t *orig_pte; 1061 pte_t *pte; 1062 1063 md = walk->private; 1064 1065 if (pmd_trans_huge_lock(pmd, md->vma) == 1) { 1066 pte_t huge_pte = *(pte_t *)pmd; 1067 struct page *page; 1068 1069 page = can_gather_numa_stats(huge_pte, md->vma, addr); 1070 if (page) 1071 gather_stats(page, md, pte_dirty(huge_pte), 1072 HPAGE_PMD_SIZE/PAGE_SIZE); 1073 spin_unlock(&walk->mm->page_table_lock); 1074 return 0; 1075 } 1076 1077 if (pmd_trans_unstable(pmd)) 1078 return 0; 1079 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1080 do { 1081 struct page *page = can_gather_numa_stats(*pte, md->vma, addr); 1082 if (!page) 1083 continue; 1084 gather_stats(page, md, pte_dirty(*pte), 1); 1085 1086 } while (pte++, addr += PAGE_SIZE, addr != end); 1087 pte_unmap_unlock(orig_pte, ptl); 1088 return 0; 1089 } 1090 #ifdef CONFIG_HUGETLB_PAGE 1091 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1092 unsigned long addr, unsigned long end, struct mm_walk *walk) 1093 { 1094 struct numa_maps *md; 1095 struct page *page; 1096 1097 if (pte_none(*pte)) 1098 return 0; 1099 1100 page = pte_page(*pte); 1101 if (!page) 1102 return 0; 1103 1104 md = walk->private; 1105 gather_stats(page, md, pte_dirty(*pte), 1); 1106 return 0; 1107 } 1108 1109 #else 1110 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1111 unsigned long addr, unsigned long end, struct mm_walk *walk) 1112 { 1113 return 0; 1114 } 1115 #endif 1116 1117 /* 1118 * Display pages allocated per node and memory policy via /proc. 1119 */ 1120 static int show_numa_map(struct seq_file *m, void *v, int is_pid) 1121 { 1122 struct numa_maps_private *numa_priv = m->private; 1123 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1124 struct vm_area_struct *vma = v; 1125 struct numa_maps *md = &numa_priv->md; 1126 struct file *file = vma->vm_file; 1127 struct mm_struct *mm = vma->vm_mm; 1128 struct mm_walk walk = {}; 1129 struct mempolicy *pol; 1130 int n; 1131 char buffer[50]; 1132 1133 if (!mm) 1134 return 0; 1135 1136 /* Ensure we start with an empty set of numa_maps statistics. */ 1137 memset(md, 0, sizeof(*md)); 1138 1139 md->vma = vma; 1140 1141 walk.hugetlb_entry = gather_hugetbl_stats; 1142 walk.pmd_entry = gather_pte_stats; 1143 walk.private = md; 1144 walk.mm = mm; 1145 1146 pol = get_vma_policy(proc_priv->task, vma, vma->vm_start); 1147 mpol_to_str(buffer, sizeof(buffer), pol, 0); 1148 mpol_cond_put(pol); 1149 1150 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1151 1152 if (file) { 1153 seq_printf(m, " file="); 1154 seq_path(m, &file->f_path, "\n\t= "); 1155 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1156 seq_printf(m, " heap"); 1157 } else { 1158 pid_t tid = vm_is_stack(proc_priv->task, vma, is_pid); 1159 if (tid != 0) { 1160 /* 1161 * Thread stack in /proc/PID/task/TID/maps or 1162 * the main process stack. 1163 */ 1164 if (!is_pid || (vma->vm_start <= mm->start_stack && 1165 vma->vm_end >= mm->start_stack)) 1166 seq_printf(m, " stack"); 1167 else 1168 seq_printf(m, " stack:%d", tid); 1169 } 1170 } 1171 1172 if (is_vm_hugetlb_page(vma)) 1173 seq_printf(m, " huge"); 1174 1175 walk_page_range(vma->vm_start, vma->vm_end, &walk); 1176 1177 if (!md->pages) 1178 goto out; 1179 1180 if (md->anon) 1181 seq_printf(m, " anon=%lu", md->anon); 1182 1183 if (md->dirty) 1184 seq_printf(m, " dirty=%lu", md->dirty); 1185 1186 if (md->pages != md->anon && md->pages != md->dirty) 1187 seq_printf(m, " mapped=%lu", md->pages); 1188 1189 if (md->mapcount_max > 1) 1190 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1191 1192 if (md->swapcache) 1193 seq_printf(m, " swapcache=%lu", md->swapcache); 1194 1195 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1196 seq_printf(m, " active=%lu", md->active); 1197 1198 if (md->writeback) 1199 seq_printf(m, " writeback=%lu", md->writeback); 1200 1201 for_each_node_state(n, N_HIGH_MEMORY) 1202 if (md->node[n]) 1203 seq_printf(m, " N%d=%lu", n, md->node[n]); 1204 out: 1205 seq_putc(m, '\n'); 1206 1207 if (m->count < m->size) 1208 m->version = (vma != proc_priv->tail_vma) ? vma->vm_start : 0; 1209 return 0; 1210 } 1211 1212 static int show_pid_numa_map(struct seq_file *m, void *v) 1213 { 1214 return show_numa_map(m, v, 1); 1215 } 1216 1217 static int show_tid_numa_map(struct seq_file *m, void *v) 1218 { 1219 return show_numa_map(m, v, 0); 1220 } 1221 1222 static const struct seq_operations proc_pid_numa_maps_op = { 1223 .start = m_start, 1224 .next = m_next, 1225 .stop = m_stop, 1226 .show = show_pid_numa_map, 1227 }; 1228 1229 static const struct seq_operations proc_tid_numa_maps_op = { 1230 .start = m_start, 1231 .next = m_next, 1232 .stop = m_stop, 1233 .show = show_tid_numa_map, 1234 }; 1235 1236 static int numa_maps_open(struct inode *inode, struct file *file, 1237 const struct seq_operations *ops) 1238 { 1239 struct numa_maps_private *priv; 1240 int ret = -ENOMEM; 1241 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 1242 if (priv) { 1243 priv->proc_maps.pid = proc_pid(inode); 1244 ret = seq_open(file, ops); 1245 if (!ret) { 1246 struct seq_file *m = file->private_data; 1247 m->private = priv; 1248 } else { 1249 kfree(priv); 1250 } 1251 } 1252 return ret; 1253 } 1254 1255 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1256 { 1257 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1258 } 1259 1260 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1261 { 1262 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1263 } 1264 1265 const struct file_operations proc_pid_numa_maps_operations = { 1266 .open = pid_numa_maps_open, 1267 .read = seq_read, 1268 .llseek = seq_lseek, 1269 .release = seq_release_private, 1270 }; 1271 1272 const struct file_operations proc_tid_numa_maps_operations = { 1273 .open = tid_numa_maps_open, 1274 .read = seq_read, 1275 .llseek = seq_lseek, 1276 .release = seq_release_private, 1277 }; 1278 #endif /* CONFIG_NUMA */ 1279