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/swapops.h> 15 #include <linux/mmu_notifier.h> 16 17 #include <asm/elf.h> 18 #include <asm/uaccess.h> 19 #include <asm/tlbflush.h> 20 #include "internal.h" 21 22 void task_mem(struct seq_file *m, struct mm_struct *mm) 23 { 24 unsigned long data, text, lib, swap; 25 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 26 27 /* 28 * Note: to minimize their overhead, mm maintains hiwater_vm and 29 * hiwater_rss only when about to *lower* total_vm or rss. Any 30 * collector of these hiwater stats must therefore get total_vm 31 * and rss too, which will usually be the higher. Barriers? not 32 * worth the effort, such snapshots can always be inconsistent. 33 */ 34 hiwater_vm = total_vm = mm->total_vm; 35 if (hiwater_vm < mm->hiwater_vm) 36 hiwater_vm = mm->hiwater_vm; 37 hiwater_rss = total_rss = get_mm_rss(mm); 38 if (hiwater_rss < mm->hiwater_rss) 39 hiwater_rss = mm->hiwater_rss; 40 41 data = mm->total_vm - mm->shared_vm - mm->stack_vm; 42 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; 43 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; 44 swap = get_mm_counter(mm, MM_SWAPENTS); 45 seq_printf(m, 46 "VmPeak:\t%8lu kB\n" 47 "VmSize:\t%8lu kB\n" 48 "VmLck:\t%8lu kB\n" 49 "VmPin:\t%8lu kB\n" 50 "VmHWM:\t%8lu kB\n" 51 "VmRSS:\t%8lu kB\n" 52 "VmData:\t%8lu kB\n" 53 "VmStk:\t%8lu kB\n" 54 "VmExe:\t%8lu kB\n" 55 "VmLib:\t%8lu kB\n" 56 "VmPTE:\t%8lu kB\n" 57 "VmSwap:\t%8lu kB\n", 58 hiwater_vm << (PAGE_SHIFT-10), 59 total_vm << (PAGE_SHIFT-10), 60 mm->locked_vm << (PAGE_SHIFT-10), 61 mm->pinned_vm << (PAGE_SHIFT-10), 62 hiwater_rss << (PAGE_SHIFT-10), 63 total_rss << (PAGE_SHIFT-10), 64 data << (PAGE_SHIFT-10), 65 mm->stack_vm << (PAGE_SHIFT-10), text, lib, 66 (PTRS_PER_PTE * sizeof(pte_t) * 67 atomic_long_read(&mm->nr_ptes)) >> 10, 68 swap << (PAGE_SHIFT-10)); 69 } 70 71 unsigned long task_vsize(struct mm_struct *mm) 72 { 73 return PAGE_SIZE * mm->total_vm; 74 } 75 76 unsigned long task_statm(struct mm_struct *mm, 77 unsigned long *shared, unsigned long *text, 78 unsigned long *data, unsigned long *resident) 79 { 80 *shared = get_mm_counter(mm, MM_FILEPAGES); 81 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 82 >> PAGE_SHIFT; 83 *data = mm->total_vm - mm->shared_vm; 84 *resident = *shared + get_mm_counter(mm, MM_ANONPAGES); 85 return mm->total_vm; 86 } 87 88 #ifdef CONFIG_NUMA 89 /* 90 * These functions are for numa_maps but called in generic **maps seq_file 91 * ->start(), ->stop() ops. 92 * 93 * numa_maps scans all vmas under mmap_sem and checks their mempolicy. 94 * Each mempolicy object is controlled by reference counting. The problem here 95 * is how to avoid accessing dead mempolicy object. 96 * 97 * Because we're holding mmap_sem while reading seq_file, it's safe to access 98 * each vma's mempolicy, no vma objects will never drop refs to mempolicy. 99 * 100 * A task's mempolicy (task->mempolicy) has different behavior. task->mempolicy 101 * is set and replaced under mmap_sem but unrefed and cleared under task_lock(). 102 * So, without task_lock(), we cannot trust get_vma_policy() because we cannot 103 * gurantee the task never exits under us. But taking task_lock() around 104 * get_vma_plicy() causes lock order problem. 105 * 106 * To access task->mempolicy without lock, we hold a reference count of an 107 * object pointed by task->mempolicy and remember it. This will guarantee 108 * that task->mempolicy points to an alive object or NULL in numa_maps accesses. 109 */ 110 static void hold_task_mempolicy(struct proc_maps_private *priv) 111 { 112 struct task_struct *task = priv->task; 113 114 task_lock(task); 115 priv->task_mempolicy = task->mempolicy; 116 mpol_get(priv->task_mempolicy); 117 task_unlock(task); 118 } 119 static void release_task_mempolicy(struct proc_maps_private *priv) 120 { 121 mpol_put(priv->task_mempolicy); 122 } 123 #else 124 static void hold_task_mempolicy(struct proc_maps_private *priv) 125 { 126 } 127 static void release_task_mempolicy(struct proc_maps_private *priv) 128 { 129 } 130 #endif 131 132 static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma) 133 { 134 if (vma && vma != priv->tail_vma) { 135 struct mm_struct *mm = vma->vm_mm; 136 release_task_mempolicy(priv); 137 up_read(&mm->mmap_sem); 138 mmput(mm); 139 } 140 } 141 142 static void *m_start(struct seq_file *m, loff_t *pos) 143 { 144 struct proc_maps_private *priv = m->private; 145 unsigned long last_addr = m->version; 146 struct mm_struct *mm; 147 struct vm_area_struct *vma, *tail_vma = NULL; 148 loff_t l = *pos; 149 150 /* Clear the per syscall fields in priv */ 151 priv->task = NULL; 152 priv->tail_vma = NULL; 153 154 /* 155 * We remember last_addr rather than next_addr to hit with 156 * vmacache most of the time. We have zero last_addr at 157 * the beginning and also after lseek. We will have -1 last_addr 158 * after the end of the vmas. 159 */ 160 161 if (last_addr == -1UL) 162 return NULL; 163 164 priv->task = get_pid_task(priv->pid, PIDTYPE_PID); 165 if (!priv->task) 166 return ERR_PTR(-ESRCH); 167 168 mm = mm_access(priv->task, PTRACE_MODE_READ); 169 if (!mm || IS_ERR(mm)) 170 return mm; 171 down_read(&mm->mmap_sem); 172 173 tail_vma = get_gate_vma(priv->task->mm); 174 priv->tail_vma = tail_vma; 175 hold_task_mempolicy(priv); 176 /* Start with last addr hint */ 177 vma = find_vma(mm, last_addr); 178 if (last_addr && vma) { 179 vma = vma->vm_next; 180 goto out; 181 } 182 183 /* 184 * Check the vma index is within the range and do 185 * sequential scan until m_index. 186 */ 187 vma = NULL; 188 if ((unsigned long)l < mm->map_count) { 189 vma = mm->mmap; 190 while (l-- && vma) 191 vma = vma->vm_next; 192 goto out; 193 } 194 195 if (l != mm->map_count) 196 tail_vma = NULL; /* After gate vma */ 197 198 out: 199 if (vma) 200 return vma; 201 202 release_task_mempolicy(priv); 203 /* End of vmas has been reached */ 204 m->version = (tail_vma != NULL)? 0: -1UL; 205 up_read(&mm->mmap_sem); 206 mmput(mm); 207 return tail_vma; 208 } 209 210 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 211 { 212 struct proc_maps_private *priv = m->private; 213 struct vm_area_struct *vma = v; 214 struct vm_area_struct *tail_vma = priv->tail_vma; 215 216 (*pos)++; 217 if (vma && (vma != tail_vma) && vma->vm_next) 218 return vma->vm_next; 219 vma_stop(priv, vma); 220 return (vma != tail_vma)? tail_vma: NULL; 221 } 222 223 static void m_stop(struct seq_file *m, void *v) 224 { 225 struct proc_maps_private *priv = m->private; 226 struct vm_area_struct *vma = v; 227 228 if (!IS_ERR(vma)) 229 vma_stop(priv, vma); 230 if (priv->task) 231 put_task_struct(priv->task); 232 } 233 234 static int do_maps_open(struct inode *inode, struct file *file, 235 const struct seq_operations *ops) 236 { 237 struct proc_maps_private *priv; 238 int ret = -ENOMEM; 239 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 240 if (priv) { 241 priv->pid = proc_pid(inode); 242 ret = seq_open(file, ops); 243 if (!ret) { 244 struct seq_file *m = file->private_data; 245 m->private = priv; 246 } else { 247 kfree(priv); 248 } 249 } 250 return ret; 251 } 252 253 static void 254 show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid) 255 { 256 struct mm_struct *mm = vma->vm_mm; 257 struct file *file = vma->vm_file; 258 struct proc_maps_private *priv = m->private; 259 struct task_struct *task = priv->task; 260 vm_flags_t flags = vma->vm_flags; 261 unsigned long ino = 0; 262 unsigned long long pgoff = 0; 263 unsigned long start, end; 264 dev_t dev = 0; 265 const char *name = NULL; 266 267 if (file) { 268 struct inode *inode = file_inode(vma->vm_file); 269 dev = inode->i_sb->s_dev; 270 ino = inode->i_ino; 271 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 272 } 273 274 /* We don't show the stack guard page in /proc/maps */ 275 start = vma->vm_start; 276 if (stack_guard_page_start(vma, start)) 277 start += PAGE_SIZE; 278 end = vma->vm_end; 279 if (stack_guard_page_end(vma, end)) 280 end -= PAGE_SIZE; 281 282 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1); 283 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ", 284 start, 285 end, 286 flags & VM_READ ? 'r' : '-', 287 flags & VM_WRITE ? 'w' : '-', 288 flags & VM_EXEC ? 'x' : '-', 289 flags & VM_MAYSHARE ? 's' : 'p', 290 pgoff, 291 MAJOR(dev), MINOR(dev), ino); 292 293 /* 294 * Print the dentry name for named mappings, and a 295 * special [heap] marker for the heap: 296 */ 297 if (file) { 298 seq_pad(m, ' '); 299 seq_path(m, &file->f_path, "\n"); 300 goto done; 301 } 302 303 name = arch_vma_name(vma); 304 if (!name) { 305 pid_t tid; 306 307 if (!mm) { 308 name = "[vdso]"; 309 goto done; 310 } 311 312 if (vma->vm_start <= mm->brk && 313 vma->vm_end >= mm->start_brk) { 314 name = "[heap]"; 315 goto done; 316 } 317 318 tid = vm_is_stack(task, vma, is_pid); 319 320 if (tid != 0) { 321 /* 322 * Thread stack in /proc/PID/task/TID/maps or 323 * the main process stack. 324 */ 325 if (!is_pid || (vma->vm_start <= mm->start_stack && 326 vma->vm_end >= mm->start_stack)) { 327 name = "[stack]"; 328 } else { 329 /* Thread stack in /proc/PID/maps */ 330 seq_pad(m, ' '); 331 seq_printf(m, "[stack:%d]", tid); 332 } 333 } 334 } 335 336 done: 337 if (name) { 338 seq_pad(m, ' '); 339 seq_puts(m, name); 340 } 341 seq_putc(m, '\n'); 342 } 343 344 static int show_map(struct seq_file *m, void *v, int is_pid) 345 { 346 struct vm_area_struct *vma = v; 347 struct proc_maps_private *priv = m->private; 348 struct task_struct *task = priv->task; 349 350 show_map_vma(m, vma, is_pid); 351 352 if (m->count < m->size) /* vma is copied successfully */ 353 m->version = (vma != get_gate_vma(task->mm)) 354 ? vma->vm_start : 0; 355 return 0; 356 } 357 358 static int show_pid_map(struct seq_file *m, void *v) 359 { 360 return show_map(m, v, 1); 361 } 362 363 static int show_tid_map(struct seq_file *m, void *v) 364 { 365 return show_map(m, v, 0); 366 } 367 368 static const struct seq_operations proc_pid_maps_op = { 369 .start = m_start, 370 .next = m_next, 371 .stop = m_stop, 372 .show = show_pid_map 373 }; 374 375 static const struct seq_operations proc_tid_maps_op = { 376 .start = m_start, 377 .next = m_next, 378 .stop = m_stop, 379 .show = show_tid_map 380 }; 381 382 static int pid_maps_open(struct inode *inode, struct file *file) 383 { 384 return do_maps_open(inode, file, &proc_pid_maps_op); 385 } 386 387 static int tid_maps_open(struct inode *inode, struct file *file) 388 { 389 return do_maps_open(inode, file, &proc_tid_maps_op); 390 } 391 392 const struct file_operations proc_pid_maps_operations = { 393 .open = pid_maps_open, 394 .read = seq_read, 395 .llseek = seq_lseek, 396 .release = seq_release_private, 397 }; 398 399 const struct file_operations proc_tid_maps_operations = { 400 .open = tid_maps_open, 401 .read = seq_read, 402 .llseek = seq_lseek, 403 .release = seq_release_private, 404 }; 405 406 /* 407 * Proportional Set Size(PSS): my share of RSS. 408 * 409 * PSS of a process is the count of pages it has in memory, where each 410 * page is divided by the number of processes sharing it. So if a 411 * process has 1000 pages all to itself, and 1000 shared with one other 412 * process, its PSS will be 1500. 413 * 414 * To keep (accumulated) division errors low, we adopt a 64bit 415 * fixed-point pss counter to minimize division errors. So (pss >> 416 * PSS_SHIFT) would be the real byte count. 417 * 418 * A shift of 12 before division means (assuming 4K page size): 419 * - 1M 3-user-pages add up to 8KB errors; 420 * - supports mapcount up to 2^24, or 16M; 421 * - supports PSS up to 2^52 bytes, or 4PB. 422 */ 423 #define PSS_SHIFT 12 424 425 #ifdef CONFIG_PROC_PAGE_MONITOR 426 struct mem_size_stats { 427 struct vm_area_struct *vma; 428 unsigned long resident; 429 unsigned long shared_clean; 430 unsigned long shared_dirty; 431 unsigned long private_clean; 432 unsigned long private_dirty; 433 unsigned long referenced; 434 unsigned long anonymous; 435 unsigned long anonymous_thp; 436 unsigned long swap; 437 unsigned long nonlinear; 438 u64 pss; 439 }; 440 441 442 static void smaps_pte_entry(pte_t ptent, unsigned long addr, 443 unsigned long ptent_size, struct mm_walk *walk) 444 { 445 struct mem_size_stats *mss = walk->private; 446 struct vm_area_struct *vma = mss->vma; 447 pgoff_t pgoff = linear_page_index(vma, addr); 448 struct page *page = NULL; 449 int mapcount; 450 451 if (pte_present(ptent)) { 452 page = vm_normal_page(vma, addr, ptent); 453 } else if (is_swap_pte(ptent)) { 454 swp_entry_t swpent = pte_to_swp_entry(ptent); 455 456 if (!non_swap_entry(swpent)) 457 mss->swap += ptent_size; 458 else if (is_migration_entry(swpent)) 459 page = migration_entry_to_page(swpent); 460 } else if (pte_file(ptent)) { 461 if (pte_to_pgoff(ptent) != pgoff) 462 mss->nonlinear += ptent_size; 463 } 464 465 if (!page) 466 return; 467 468 if (PageAnon(page)) 469 mss->anonymous += ptent_size; 470 471 if (page->index != pgoff) 472 mss->nonlinear += ptent_size; 473 474 mss->resident += ptent_size; 475 /* Accumulate the size in pages that have been accessed. */ 476 if (pte_young(ptent) || PageReferenced(page)) 477 mss->referenced += ptent_size; 478 mapcount = page_mapcount(page); 479 if (mapcount >= 2) { 480 if (pte_dirty(ptent) || PageDirty(page)) 481 mss->shared_dirty += ptent_size; 482 else 483 mss->shared_clean += ptent_size; 484 mss->pss += (ptent_size << PSS_SHIFT) / mapcount; 485 } else { 486 if (pte_dirty(ptent) || PageDirty(page)) 487 mss->private_dirty += ptent_size; 488 else 489 mss->private_clean += ptent_size; 490 mss->pss += (ptent_size << PSS_SHIFT); 491 } 492 } 493 494 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 495 struct mm_walk *walk) 496 { 497 struct mem_size_stats *mss = walk->private; 498 struct vm_area_struct *vma = mss->vma; 499 pte_t *pte; 500 spinlock_t *ptl; 501 502 if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { 503 smaps_pte_entry(*(pte_t *)pmd, addr, HPAGE_PMD_SIZE, walk); 504 spin_unlock(ptl); 505 mss->anonymous_thp += HPAGE_PMD_SIZE; 506 return 0; 507 } 508 509 if (pmd_trans_unstable(pmd)) 510 return 0; 511 /* 512 * The mmap_sem held all the way back in m_start() is what 513 * keeps khugepaged out of here and from collapsing things 514 * in here. 515 */ 516 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 517 for (; addr != end; pte++, addr += PAGE_SIZE) 518 smaps_pte_entry(*pte, addr, PAGE_SIZE, walk); 519 pte_unmap_unlock(pte - 1, ptl); 520 cond_resched(); 521 return 0; 522 } 523 524 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) 525 { 526 /* 527 * Don't forget to update Documentation/ on changes. 528 */ 529 static const char mnemonics[BITS_PER_LONG][2] = { 530 /* 531 * In case if we meet a flag we don't know about. 532 */ 533 [0 ... (BITS_PER_LONG-1)] = "??", 534 535 [ilog2(VM_READ)] = "rd", 536 [ilog2(VM_WRITE)] = "wr", 537 [ilog2(VM_EXEC)] = "ex", 538 [ilog2(VM_SHARED)] = "sh", 539 [ilog2(VM_MAYREAD)] = "mr", 540 [ilog2(VM_MAYWRITE)] = "mw", 541 [ilog2(VM_MAYEXEC)] = "me", 542 [ilog2(VM_MAYSHARE)] = "ms", 543 [ilog2(VM_GROWSDOWN)] = "gd", 544 [ilog2(VM_PFNMAP)] = "pf", 545 [ilog2(VM_DENYWRITE)] = "dw", 546 [ilog2(VM_LOCKED)] = "lo", 547 [ilog2(VM_IO)] = "io", 548 [ilog2(VM_SEQ_READ)] = "sr", 549 [ilog2(VM_RAND_READ)] = "rr", 550 [ilog2(VM_DONTCOPY)] = "dc", 551 [ilog2(VM_DONTEXPAND)] = "de", 552 [ilog2(VM_ACCOUNT)] = "ac", 553 [ilog2(VM_NORESERVE)] = "nr", 554 [ilog2(VM_HUGETLB)] = "ht", 555 [ilog2(VM_NONLINEAR)] = "nl", 556 [ilog2(VM_ARCH_1)] = "ar", 557 [ilog2(VM_DONTDUMP)] = "dd", 558 #ifdef CONFIG_MEM_SOFT_DIRTY 559 [ilog2(VM_SOFTDIRTY)] = "sd", 560 #endif 561 [ilog2(VM_MIXEDMAP)] = "mm", 562 [ilog2(VM_HUGEPAGE)] = "hg", 563 [ilog2(VM_NOHUGEPAGE)] = "nh", 564 [ilog2(VM_MERGEABLE)] = "mg", 565 }; 566 size_t i; 567 568 seq_puts(m, "VmFlags: "); 569 for (i = 0; i < BITS_PER_LONG; i++) { 570 if (vma->vm_flags & (1UL << i)) { 571 seq_printf(m, "%c%c ", 572 mnemonics[i][0], mnemonics[i][1]); 573 } 574 } 575 seq_putc(m, '\n'); 576 } 577 578 static int show_smap(struct seq_file *m, void *v, int is_pid) 579 { 580 struct proc_maps_private *priv = m->private; 581 struct task_struct *task = priv->task; 582 struct vm_area_struct *vma = v; 583 struct mem_size_stats mss; 584 struct mm_walk smaps_walk = { 585 .pmd_entry = smaps_pte_range, 586 .mm = vma->vm_mm, 587 .private = &mss, 588 }; 589 590 memset(&mss, 0, sizeof mss); 591 mss.vma = vma; 592 /* mmap_sem is held in m_start */ 593 if (vma->vm_mm && !is_vm_hugetlb_page(vma)) 594 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk); 595 596 show_map_vma(m, vma, is_pid); 597 598 seq_printf(m, 599 "Size: %8lu kB\n" 600 "Rss: %8lu kB\n" 601 "Pss: %8lu kB\n" 602 "Shared_Clean: %8lu kB\n" 603 "Shared_Dirty: %8lu kB\n" 604 "Private_Clean: %8lu kB\n" 605 "Private_Dirty: %8lu kB\n" 606 "Referenced: %8lu kB\n" 607 "Anonymous: %8lu kB\n" 608 "AnonHugePages: %8lu kB\n" 609 "Swap: %8lu kB\n" 610 "KernelPageSize: %8lu kB\n" 611 "MMUPageSize: %8lu kB\n" 612 "Locked: %8lu kB\n", 613 (vma->vm_end - vma->vm_start) >> 10, 614 mss.resident >> 10, 615 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)), 616 mss.shared_clean >> 10, 617 mss.shared_dirty >> 10, 618 mss.private_clean >> 10, 619 mss.private_dirty >> 10, 620 mss.referenced >> 10, 621 mss.anonymous >> 10, 622 mss.anonymous_thp >> 10, 623 mss.swap >> 10, 624 vma_kernel_pagesize(vma) >> 10, 625 vma_mmu_pagesize(vma) >> 10, 626 (vma->vm_flags & VM_LOCKED) ? 627 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0); 628 629 if (vma->vm_flags & VM_NONLINEAR) 630 seq_printf(m, "Nonlinear: %8lu kB\n", 631 mss.nonlinear >> 10); 632 633 show_smap_vma_flags(m, vma); 634 635 if (m->count < m->size) /* vma is copied successfully */ 636 m->version = (vma != get_gate_vma(task->mm)) 637 ? vma->vm_start : 0; 638 return 0; 639 } 640 641 static int show_pid_smap(struct seq_file *m, void *v) 642 { 643 return show_smap(m, v, 1); 644 } 645 646 static int show_tid_smap(struct seq_file *m, void *v) 647 { 648 return show_smap(m, v, 0); 649 } 650 651 static const struct seq_operations proc_pid_smaps_op = { 652 .start = m_start, 653 .next = m_next, 654 .stop = m_stop, 655 .show = show_pid_smap 656 }; 657 658 static const struct seq_operations proc_tid_smaps_op = { 659 .start = m_start, 660 .next = m_next, 661 .stop = m_stop, 662 .show = show_tid_smap 663 }; 664 665 static int pid_smaps_open(struct inode *inode, struct file *file) 666 { 667 return do_maps_open(inode, file, &proc_pid_smaps_op); 668 } 669 670 static int tid_smaps_open(struct inode *inode, struct file *file) 671 { 672 return do_maps_open(inode, file, &proc_tid_smaps_op); 673 } 674 675 const struct file_operations proc_pid_smaps_operations = { 676 .open = pid_smaps_open, 677 .read = seq_read, 678 .llseek = seq_lseek, 679 .release = seq_release_private, 680 }; 681 682 const struct file_operations proc_tid_smaps_operations = { 683 .open = tid_smaps_open, 684 .read = seq_read, 685 .llseek = seq_lseek, 686 .release = seq_release_private, 687 }; 688 689 /* 690 * We do not want to have constant page-shift bits sitting in 691 * pagemap entries and are about to reuse them some time soon. 692 * 693 * Here's the "migration strategy": 694 * 1. when the system boots these bits remain what they are, 695 * but a warning about future change is printed in log; 696 * 2. once anyone clears soft-dirty bits via clear_refs file, 697 * these flag is set to denote, that user is aware of the 698 * new API and those page-shift bits change their meaning. 699 * The respective warning is printed in dmesg; 700 * 3. In a couple of releases we will remove all the mentions 701 * of page-shift in pagemap entries. 702 */ 703 704 static bool soft_dirty_cleared __read_mostly; 705 706 enum clear_refs_types { 707 CLEAR_REFS_ALL = 1, 708 CLEAR_REFS_ANON, 709 CLEAR_REFS_MAPPED, 710 CLEAR_REFS_SOFT_DIRTY, 711 CLEAR_REFS_LAST, 712 }; 713 714 struct clear_refs_private { 715 struct vm_area_struct *vma; 716 enum clear_refs_types type; 717 }; 718 719 static inline void clear_soft_dirty(struct vm_area_struct *vma, 720 unsigned long addr, pte_t *pte) 721 { 722 #ifdef CONFIG_MEM_SOFT_DIRTY 723 /* 724 * The soft-dirty tracker uses #PF-s to catch writes 725 * to pages, so write-protect the pte as well. See the 726 * Documentation/vm/soft-dirty.txt for full description 727 * of how soft-dirty works. 728 */ 729 pte_t ptent = *pte; 730 731 if (pte_present(ptent)) { 732 ptent = pte_wrprotect(ptent); 733 ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY); 734 } else if (is_swap_pte(ptent)) { 735 ptent = pte_swp_clear_soft_dirty(ptent); 736 } else if (pte_file(ptent)) { 737 ptent = pte_file_clear_soft_dirty(ptent); 738 } 739 740 if (vma->vm_flags & VM_SOFTDIRTY) 741 vma->vm_flags &= ~VM_SOFTDIRTY; 742 743 set_pte_at(vma->vm_mm, addr, pte, ptent); 744 #endif 745 } 746 747 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 748 unsigned long end, struct mm_walk *walk) 749 { 750 struct clear_refs_private *cp = walk->private; 751 struct vm_area_struct *vma = cp->vma; 752 pte_t *pte, ptent; 753 spinlock_t *ptl; 754 struct page *page; 755 756 split_huge_page_pmd(vma, addr, pmd); 757 if (pmd_trans_unstable(pmd)) 758 return 0; 759 760 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 761 for (; addr != end; pte++, addr += PAGE_SIZE) { 762 ptent = *pte; 763 764 if (cp->type == CLEAR_REFS_SOFT_DIRTY) { 765 clear_soft_dirty(vma, addr, pte); 766 continue; 767 } 768 769 if (!pte_present(ptent)) 770 continue; 771 772 page = vm_normal_page(vma, addr, ptent); 773 if (!page) 774 continue; 775 776 /* Clear accessed and referenced bits. */ 777 ptep_test_and_clear_young(vma, addr, pte); 778 ClearPageReferenced(page); 779 } 780 pte_unmap_unlock(pte - 1, ptl); 781 cond_resched(); 782 return 0; 783 } 784 785 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 786 size_t count, loff_t *ppos) 787 { 788 struct task_struct *task; 789 char buffer[PROC_NUMBUF]; 790 struct mm_struct *mm; 791 struct vm_area_struct *vma; 792 enum clear_refs_types type; 793 int itype; 794 int rv; 795 796 memset(buffer, 0, sizeof(buffer)); 797 if (count > sizeof(buffer) - 1) 798 count = sizeof(buffer) - 1; 799 if (copy_from_user(buffer, buf, count)) 800 return -EFAULT; 801 rv = kstrtoint(strstrip(buffer), 10, &itype); 802 if (rv < 0) 803 return rv; 804 type = (enum clear_refs_types)itype; 805 if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST) 806 return -EINVAL; 807 808 if (type == CLEAR_REFS_SOFT_DIRTY) { 809 soft_dirty_cleared = true; 810 pr_warn_once("The pagemap bits 55-60 has changed their meaning! " 811 "See the linux/Documentation/vm/pagemap.txt for details.\n"); 812 } 813 814 task = get_proc_task(file_inode(file)); 815 if (!task) 816 return -ESRCH; 817 mm = get_task_mm(task); 818 if (mm) { 819 struct clear_refs_private cp = { 820 .type = type, 821 }; 822 struct mm_walk clear_refs_walk = { 823 .pmd_entry = clear_refs_pte_range, 824 .mm = mm, 825 .private = &cp, 826 }; 827 down_read(&mm->mmap_sem); 828 if (type == CLEAR_REFS_SOFT_DIRTY) 829 mmu_notifier_invalidate_range_start(mm, 0, -1); 830 for (vma = mm->mmap; vma; vma = vma->vm_next) { 831 cp.vma = vma; 832 if (is_vm_hugetlb_page(vma)) 833 continue; 834 /* 835 * Writing 1 to /proc/pid/clear_refs affects all pages. 836 * 837 * Writing 2 to /proc/pid/clear_refs only affects 838 * Anonymous pages. 839 * 840 * Writing 3 to /proc/pid/clear_refs only affects file 841 * mapped pages. 842 */ 843 if (type == CLEAR_REFS_ANON && vma->vm_file) 844 continue; 845 if (type == CLEAR_REFS_MAPPED && !vma->vm_file) 846 continue; 847 walk_page_range(vma->vm_start, vma->vm_end, 848 &clear_refs_walk); 849 } 850 if (type == CLEAR_REFS_SOFT_DIRTY) 851 mmu_notifier_invalidate_range_end(mm, 0, -1); 852 flush_tlb_mm(mm); 853 up_read(&mm->mmap_sem); 854 mmput(mm); 855 } 856 put_task_struct(task); 857 858 return count; 859 } 860 861 const struct file_operations proc_clear_refs_operations = { 862 .write = clear_refs_write, 863 .llseek = noop_llseek, 864 }; 865 866 typedef struct { 867 u64 pme; 868 } pagemap_entry_t; 869 870 struct pagemapread { 871 int pos, len; /* units: PM_ENTRY_BYTES, not bytes */ 872 pagemap_entry_t *buffer; 873 bool v2; 874 }; 875 876 #define PAGEMAP_WALK_SIZE (PMD_SIZE) 877 #define PAGEMAP_WALK_MASK (PMD_MASK) 878 879 #define PM_ENTRY_BYTES sizeof(pagemap_entry_t) 880 #define PM_STATUS_BITS 3 881 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) 882 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) 883 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) 884 #define PM_PSHIFT_BITS 6 885 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) 886 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) 887 #define __PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) 888 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) 889 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) 890 /* in "new" pagemap pshift bits are occupied with more status bits */ 891 #define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT)) 892 893 #define __PM_SOFT_DIRTY (1LL) 894 #define PM_PRESENT PM_STATUS(4LL) 895 #define PM_SWAP PM_STATUS(2LL) 896 #define PM_FILE PM_STATUS(1LL) 897 #define PM_NOT_PRESENT(v2) PM_STATUS2(v2, 0) 898 #define PM_END_OF_BUFFER 1 899 900 static inline pagemap_entry_t make_pme(u64 val) 901 { 902 return (pagemap_entry_t) { .pme = val }; 903 } 904 905 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme, 906 struct pagemapread *pm) 907 { 908 pm->buffer[pm->pos++] = *pme; 909 if (pm->pos >= pm->len) 910 return PM_END_OF_BUFFER; 911 return 0; 912 } 913 914 static int pagemap_pte_hole(unsigned long start, unsigned long end, 915 struct mm_walk *walk) 916 { 917 struct pagemapread *pm = walk->private; 918 unsigned long addr; 919 int err = 0; 920 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2)); 921 922 for (addr = start; addr < end; addr += PAGE_SIZE) { 923 err = add_to_pagemap(addr, &pme, pm); 924 if (err) 925 break; 926 } 927 return err; 928 } 929 930 static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 931 struct vm_area_struct *vma, unsigned long addr, pte_t pte) 932 { 933 u64 frame, flags; 934 struct page *page = NULL; 935 int flags2 = 0; 936 937 if (pte_present(pte)) { 938 frame = pte_pfn(pte); 939 flags = PM_PRESENT; 940 page = vm_normal_page(vma, addr, pte); 941 if (pte_soft_dirty(pte)) 942 flags2 |= __PM_SOFT_DIRTY; 943 } else if (is_swap_pte(pte)) { 944 swp_entry_t entry; 945 if (pte_swp_soft_dirty(pte)) 946 flags2 |= __PM_SOFT_DIRTY; 947 entry = pte_to_swp_entry(pte); 948 frame = swp_type(entry) | 949 (swp_offset(entry) << MAX_SWAPFILES_SHIFT); 950 flags = PM_SWAP; 951 if (is_migration_entry(entry)) 952 page = migration_entry_to_page(entry); 953 } else { 954 if (vma->vm_flags & VM_SOFTDIRTY) 955 flags2 |= __PM_SOFT_DIRTY; 956 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2)); 957 return; 958 } 959 960 if (page && !PageAnon(page)) 961 flags |= PM_FILE; 962 if ((vma->vm_flags & VM_SOFTDIRTY)) 963 flags2 |= __PM_SOFT_DIRTY; 964 965 *pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, flags2) | flags); 966 } 967 968 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 969 static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 970 pmd_t pmd, int offset, int pmd_flags2) 971 { 972 /* 973 * Currently pmd for thp is always present because thp can not be 974 * swapped-out, migrated, or HWPOISONed (split in such cases instead.) 975 * This if-check is just to prepare for future implementation. 976 */ 977 if (pmd_present(pmd)) 978 *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset) 979 | PM_STATUS2(pm->v2, pmd_flags2) | PM_PRESENT); 980 else 981 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, pmd_flags2)); 982 } 983 #else 984 static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 985 pmd_t pmd, int offset, int pmd_flags2) 986 { 987 } 988 #endif 989 990 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 991 struct mm_walk *walk) 992 { 993 struct vm_area_struct *vma; 994 struct pagemapread *pm = walk->private; 995 spinlock_t *ptl; 996 pte_t *pte; 997 int err = 0; 998 pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2)); 999 1000 /* find the first VMA at or above 'addr' */ 1001 vma = find_vma(walk->mm, addr); 1002 if (vma && pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { 1003 int pmd_flags2; 1004 1005 if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(*pmd)) 1006 pmd_flags2 = __PM_SOFT_DIRTY; 1007 else 1008 pmd_flags2 = 0; 1009 1010 for (; addr != end; addr += PAGE_SIZE) { 1011 unsigned long offset; 1012 1013 offset = (addr & ~PAGEMAP_WALK_MASK) >> 1014 PAGE_SHIFT; 1015 thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset, pmd_flags2); 1016 err = add_to_pagemap(addr, &pme, pm); 1017 if (err) 1018 break; 1019 } 1020 spin_unlock(ptl); 1021 return err; 1022 } 1023 1024 if (pmd_trans_unstable(pmd)) 1025 return 0; 1026 for (; addr != end; addr += PAGE_SIZE) { 1027 int flags2; 1028 1029 /* check to see if we've left 'vma' behind 1030 * and need a new, higher one */ 1031 if (vma && (addr >= vma->vm_end)) { 1032 vma = find_vma(walk->mm, addr); 1033 if (vma && (vma->vm_flags & VM_SOFTDIRTY)) 1034 flags2 = __PM_SOFT_DIRTY; 1035 else 1036 flags2 = 0; 1037 pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2)); 1038 } 1039 1040 /* check that 'vma' actually covers this address, 1041 * and that it isn't a huge page vma */ 1042 if (vma && (vma->vm_start <= addr) && 1043 !is_vm_hugetlb_page(vma)) { 1044 pte = pte_offset_map(pmd, addr); 1045 pte_to_pagemap_entry(&pme, pm, vma, addr, *pte); 1046 /* unmap before userspace copy */ 1047 pte_unmap(pte); 1048 } 1049 err = add_to_pagemap(addr, &pme, pm); 1050 if (err) 1051 return err; 1052 } 1053 1054 cond_resched(); 1055 1056 return err; 1057 } 1058 1059 #ifdef CONFIG_HUGETLB_PAGE 1060 static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, 1061 pte_t pte, int offset, int flags2) 1062 { 1063 if (pte_present(pte)) 1064 *pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) | 1065 PM_STATUS2(pm->v2, flags2) | 1066 PM_PRESENT); 1067 else 1068 *pme = make_pme(PM_NOT_PRESENT(pm->v2) | 1069 PM_STATUS2(pm->v2, flags2)); 1070 } 1071 1072 /* This function walks within one hugetlb entry in the single call */ 1073 static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask, 1074 unsigned long addr, unsigned long end, 1075 struct mm_walk *walk) 1076 { 1077 struct pagemapread *pm = walk->private; 1078 struct vm_area_struct *vma; 1079 int err = 0; 1080 int flags2; 1081 pagemap_entry_t pme; 1082 1083 vma = find_vma(walk->mm, addr); 1084 WARN_ON_ONCE(!vma); 1085 1086 if (vma && (vma->vm_flags & VM_SOFTDIRTY)) 1087 flags2 = __PM_SOFT_DIRTY; 1088 else 1089 flags2 = 0; 1090 1091 for (; addr != end; addr += PAGE_SIZE) { 1092 int offset = (addr & ~hmask) >> PAGE_SHIFT; 1093 huge_pte_to_pagemap_entry(&pme, pm, *pte, offset, flags2); 1094 err = add_to_pagemap(addr, &pme, pm); 1095 if (err) 1096 return err; 1097 } 1098 1099 cond_resched(); 1100 1101 return err; 1102 } 1103 #endif /* HUGETLB_PAGE */ 1104 1105 /* 1106 * /proc/pid/pagemap - an array mapping virtual pages to pfns 1107 * 1108 * For each page in the address space, this file contains one 64-bit entry 1109 * consisting of the following: 1110 * 1111 * Bits 0-54 page frame number (PFN) if present 1112 * Bits 0-4 swap type if swapped 1113 * Bits 5-54 swap offset if swapped 1114 * Bits 55-60 page shift (page size = 1<<page shift) 1115 * Bit 61 page is file-page or shared-anon 1116 * Bit 62 page swapped 1117 * Bit 63 page present 1118 * 1119 * If the page is not present but in swap, then the PFN contains an 1120 * encoding of the swap file number and the page's offset into the 1121 * swap. Unmapped pages return a null PFN. This allows determining 1122 * precisely which pages are mapped (or in swap) and comparing mapped 1123 * pages between processes. 1124 * 1125 * Efficient users of this interface will use /proc/pid/maps to 1126 * determine which areas of memory are actually mapped and llseek to 1127 * skip over unmapped regions. 1128 */ 1129 static ssize_t pagemap_read(struct file *file, char __user *buf, 1130 size_t count, loff_t *ppos) 1131 { 1132 struct task_struct *task = get_proc_task(file_inode(file)); 1133 struct mm_struct *mm; 1134 struct pagemapread pm; 1135 int ret = -ESRCH; 1136 struct mm_walk pagemap_walk = {}; 1137 unsigned long src; 1138 unsigned long svpfn; 1139 unsigned long start_vaddr; 1140 unsigned long end_vaddr; 1141 int copied = 0; 1142 1143 if (!task) 1144 goto out; 1145 1146 ret = -EINVAL; 1147 /* file position must be aligned */ 1148 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 1149 goto out_task; 1150 1151 ret = 0; 1152 if (!count) 1153 goto out_task; 1154 1155 pm.v2 = soft_dirty_cleared; 1156 pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT); 1157 pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY); 1158 ret = -ENOMEM; 1159 if (!pm.buffer) 1160 goto out_task; 1161 1162 mm = mm_access(task, PTRACE_MODE_READ); 1163 ret = PTR_ERR(mm); 1164 if (!mm || IS_ERR(mm)) 1165 goto out_free; 1166 1167 pagemap_walk.pmd_entry = pagemap_pte_range; 1168 pagemap_walk.pte_hole = pagemap_pte_hole; 1169 #ifdef CONFIG_HUGETLB_PAGE 1170 pagemap_walk.hugetlb_entry = pagemap_hugetlb_range; 1171 #endif 1172 pagemap_walk.mm = mm; 1173 pagemap_walk.private = ± 1174 1175 src = *ppos; 1176 svpfn = src / PM_ENTRY_BYTES; 1177 start_vaddr = svpfn << PAGE_SHIFT; 1178 end_vaddr = TASK_SIZE_OF(task); 1179 1180 /* watch out for wraparound */ 1181 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT) 1182 start_vaddr = end_vaddr; 1183 1184 /* 1185 * The odds are that this will stop walking way 1186 * before end_vaddr, because the length of the 1187 * user buffer is tracked in "pm", and the walk 1188 * will stop when we hit the end of the buffer. 1189 */ 1190 ret = 0; 1191 while (count && (start_vaddr < end_vaddr)) { 1192 int len; 1193 unsigned long end; 1194 1195 pm.pos = 0; 1196 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK; 1197 /* overflow ? */ 1198 if (end < start_vaddr || end > end_vaddr) 1199 end = end_vaddr; 1200 down_read(&mm->mmap_sem); 1201 ret = walk_page_range(start_vaddr, end, &pagemap_walk); 1202 up_read(&mm->mmap_sem); 1203 start_vaddr = end; 1204 1205 len = min(count, PM_ENTRY_BYTES * pm.pos); 1206 if (copy_to_user(buf, pm.buffer, len)) { 1207 ret = -EFAULT; 1208 goto out_mm; 1209 } 1210 copied += len; 1211 buf += len; 1212 count -= len; 1213 } 1214 *ppos += copied; 1215 if (!ret || ret == PM_END_OF_BUFFER) 1216 ret = copied; 1217 1218 out_mm: 1219 mmput(mm); 1220 out_free: 1221 kfree(pm.buffer); 1222 out_task: 1223 put_task_struct(task); 1224 out: 1225 return ret; 1226 } 1227 1228 static int pagemap_open(struct inode *inode, struct file *file) 1229 { 1230 pr_warn_once("Bits 55-60 of /proc/PID/pagemap entries are about " 1231 "to stop being page-shift some time soon. See the " 1232 "linux/Documentation/vm/pagemap.txt for details.\n"); 1233 return 0; 1234 } 1235 1236 const struct file_operations proc_pagemap_operations = { 1237 .llseek = mem_lseek, /* borrow this */ 1238 .read = pagemap_read, 1239 .open = pagemap_open, 1240 }; 1241 #endif /* CONFIG_PROC_PAGE_MONITOR */ 1242 1243 #ifdef CONFIG_NUMA 1244 1245 struct numa_maps { 1246 struct vm_area_struct *vma; 1247 unsigned long pages; 1248 unsigned long anon; 1249 unsigned long active; 1250 unsigned long writeback; 1251 unsigned long mapcount_max; 1252 unsigned long dirty; 1253 unsigned long swapcache; 1254 unsigned long node[MAX_NUMNODES]; 1255 }; 1256 1257 struct numa_maps_private { 1258 struct proc_maps_private proc_maps; 1259 struct numa_maps md; 1260 }; 1261 1262 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty, 1263 unsigned long nr_pages) 1264 { 1265 int count = page_mapcount(page); 1266 1267 md->pages += nr_pages; 1268 if (pte_dirty || PageDirty(page)) 1269 md->dirty += nr_pages; 1270 1271 if (PageSwapCache(page)) 1272 md->swapcache += nr_pages; 1273 1274 if (PageActive(page) || PageUnevictable(page)) 1275 md->active += nr_pages; 1276 1277 if (PageWriteback(page)) 1278 md->writeback += nr_pages; 1279 1280 if (PageAnon(page)) 1281 md->anon += nr_pages; 1282 1283 if (count > md->mapcount_max) 1284 md->mapcount_max = count; 1285 1286 md->node[page_to_nid(page)] += nr_pages; 1287 } 1288 1289 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma, 1290 unsigned long addr) 1291 { 1292 struct page *page; 1293 int nid; 1294 1295 if (!pte_present(pte)) 1296 return NULL; 1297 1298 page = vm_normal_page(vma, addr, pte); 1299 if (!page) 1300 return NULL; 1301 1302 if (PageReserved(page)) 1303 return NULL; 1304 1305 nid = page_to_nid(page); 1306 if (!node_isset(nid, node_states[N_MEMORY])) 1307 return NULL; 1308 1309 return page; 1310 } 1311 1312 static int gather_pte_stats(pmd_t *pmd, unsigned long addr, 1313 unsigned long end, struct mm_walk *walk) 1314 { 1315 struct numa_maps *md; 1316 spinlock_t *ptl; 1317 pte_t *orig_pte; 1318 pte_t *pte; 1319 1320 md = walk->private; 1321 1322 if (pmd_trans_huge_lock(pmd, md->vma, &ptl) == 1) { 1323 pte_t huge_pte = *(pte_t *)pmd; 1324 struct page *page; 1325 1326 page = can_gather_numa_stats(huge_pte, md->vma, addr); 1327 if (page) 1328 gather_stats(page, md, pte_dirty(huge_pte), 1329 HPAGE_PMD_SIZE/PAGE_SIZE); 1330 spin_unlock(ptl); 1331 return 0; 1332 } 1333 1334 if (pmd_trans_unstable(pmd)) 1335 return 0; 1336 orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); 1337 do { 1338 struct page *page = can_gather_numa_stats(*pte, md->vma, addr); 1339 if (!page) 1340 continue; 1341 gather_stats(page, md, pte_dirty(*pte), 1); 1342 1343 } while (pte++, addr += PAGE_SIZE, addr != end); 1344 pte_unmap_unlock(orig_pte, ptl); 1345 return 0; 1346 } 1347 #ifdef CONFIG_HUGETLB_PAGE 1348 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1349 unsigned long addr, unsigned long end, struct mm_walk *walk) 1350 { 1351 struct numa_maps *md; 1352 struct page *page; 1353 1354 if (pte_none(*pte)) 1355 return 0; 1356 1357 page = pte_page(*pte); 1358 if (!page) 1359 return 0; 1360 1361 md = walk->private; 1362 gather_stats(page, md, pte_dirty(*pte), 1); 1363 return 0; 1364 } 1365 1366 #else 1367 static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask, 1368 unsigned long addr, unsigned long end, struct mm_walk *walk) 1369 { 1370 return 0; 1371 } 1372 #endif 1373 1374 /* 1375 * Display pages allocated per node and memory policy via /proc. 1376 */ 1377 static int show_numa_map(struct seq_file *m, void *v, int is_pid) 1378 { 1379 struct numa_maps_private *numa_priv = m->private; 1380 struct proc_maps_private *proc_priv = &numa_priv->proc_maps; 1381 struct vm_area_struct *vma = v; 1382 struct numa_maps *md = &numa_priv->md; 1383 struct file *file = vma->vm_file; 1384 struct task_struct *task = proc_priv->task; 1385 struct mm_struct *mm = vma->vm_mm; 1386 struct mm_walk walk = {}; 1387 struct mempolicy *pol; 1388 char buffer[64]; 1389 int nid; 1390 1391 if (!mm) 1392 return 0; 1393 1394 /* Ensure we start with an empty set of numa_maps statistics. */ 1395 memset(md, 0, sizeof(*md)); 1396 1397 md->vma = vma; 1398 1399 walk.hugetlb_entry = gather_hugetbl_stats; 1400 walk.pmd_entry = gather_pte_stats; 1401 walk.private = md; 1402 walk.mm = mm; 1403 1404 pol = get_vma_policy(task, vma, vma->vm_start); 1405 mpol_to_str(buffer, sizeof(buffer), pol); 1406 mpol_cond_put(pol); 1407 1408 seq_printf(m, "%08lx %s", vma->vm_start, buffer); 1409 1410 if (file) { 1411 seq_printf(m, " file="); 1412 seq_path(m, &file->f_path, "\n\t= "); 1413 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) { 1414 seq_printf(m, " heap"); 1415 } else { 1416 pid_t tid = vm_is_stack(task, vma, is_pid); 1417 if (tid != 0) { 1418 /* 1419 * Thread stack in /proc/PID/task/TID/maps or 1420 * the main process stack. 1421 */ 1422 if (!is_pid || (vma->vm_start <= mm->start_stack && 1423 vma->vm_end >= mm->start_stack)) 1424 seq_printf(m, " stack"); 1425 else 1426 seq_printf(m, " stack:%d", tid); 1427 } 1428 } 1429 1430 if (is_vm_hugetlb_page(vma)) 1431 seq_printf(m, " huge"); 1432 1433 walk_page_range(vma->vm_start, vma->vm_end, &walk); 1434 1435 if (!md->pages) 1436 goto out; 1437 1438 if (md->anon) 1439 seq_printf(m, " anon=%lu", md->anon); 1440 1441 if (md->dirty) 1442 seq_printf(m, " dirty=%lu", md->dirty); 1443 1444 if (md->pages != md->anon && md->pages != md->dirty) 1445 seq_printf(m, " mapped=%lu", md->pages); 1446 1447 if (md->mapcount_max > 1) 1448 seq_printf(m, " mapmax=%lu", md->mapcount_max); 1449 1450 if (md->swapcache) 1451 seq_printf(m, " swapcache=%lu", md->swapcache); 1452 1453 if (md->active < md->pages && !is_vm_hugetlb_page(vma)) 1454 seq_printf(m, " active=%lu", md->active); 1455 1456 if (md->writeback) 1457 seq_printf(m, " writeback=%lu", md->writeback); 1458 1459 for_each_node_state(nid, N_MEMORY) 1460 if (md->node[nid]) 1461 seq_printf(m, " N%d=%lu", nid, md->node[nid]); 1462 out: 1463 seq_putc(m, '\n'); 1464 1465 if (m->count < m->size) 1466 m->version = (vma != proc_priv->tail_vma) ? vma->vm_start : 0; 1467 return 0; 1468 } 1469 1470 static int show_pid_numa_map(struct seq_file *m, void *v) 1471 { 1472 return show_numa_map(m, v, 1); 1473 } 1474 1475 static int show_tid_numa_map(struct seq_file *m, void *v) 1476 { 1477 return show_numa_map(m, v, 0); 1478 } 1479 1480 static const struct seq_operations proc_pid_numa_maps_op = { 1481 .start = m_start, 1482 .next = m_next, 1483 .stop = m_stop, 1484 .show = show_pid_numa_map, 1485 }; 1486 1487 static const struct seq_operations proc_tid_numa_maps_op = { 1488 .start = m_start, 1489 .next = m_next, 1490 .stop = m_stop, 1491 .show = show_tid_numa_map, 1492 }; 1493 1494 static int numa_maps_open(struct inode *inode, struct file *file, 1495 const struct seq_operations *ops) 1496 { 1497 struct numa_maps_private *priv; 1498 int ret = -ENOMEM; 1499 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 1500 if (priv) { 1501 priv->proc_maps.pid = proc_pid(inode); 1502 ret = seq_open(file, ops); 1503 if (!ret) { 1504 struct seq_file *m = file->private_data; 1505 m->private = priv; 1506 } else { 1507 kfree(priv); 1508 } 1509 } 1510 return ret; 1511 } 1512 1513 static int pid_numa_maps_open(struct inode *inode, struct file *file) 1514 { 1515 return numa_maps_open(inode, file, &proc_pid_numa_maps_op); 1516 } 1517 1518 static int tid_numa_maps_open(struct inode *inode, struct file *file) 1519 { 1520 return numa_maps_open(inode, file, &proc_tid_numa_maps_op); 1521 } 1522 1523 const struct file_operations proc_pid_numa_maps_operations = { 1524 .open = pid_numa_maps_open, 1525 .read = seq_read, 1526 .llseek = seq_lseek, 1527 .release = seq_release_private, 1528 }; 1529 1530 const struct file_operations proc_tid_numa_maps_operations = { 1531 .open = tid_numa_maps_open, 1532 .read = seq_read, 1533 .llseek = seq_lseek, 1534 .release = seq_release_private, 1535 }; 1536 #endif /* CONFIG_NUMA */ 1537