fs/proc/task_mmu.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/pagewalk.h>
   3 #include <linux/vmacache.h>
   4 #include <linux/hugetlb.h>
   5 #include <linux/huge_mm.h>
   6 #include <linux/mount.h>
   7 #include <linux/seq_file.h>
   8 #include <linux/highmem.h>
   9 #include <linux/ptrace.h>
  10 #include <linux/slab.h>
  11 #include <linux/pagemap.h>
  12 #include <linux/mempolicy.h>
  13 #include <linux/rmap.h>
  14 #include <linux/swap.h>
  15 #include <linux/sched/mm.h>
  16 #include <linux/swapops.h>
  17 #include <linux/mmu_notifier.h>
  18 #include <linux/page_idle.h>
  19 #include <linux/shmem_fs.h>
  20 #include <linux/uaccess.h>
  21 #include <linux/pkeys.h>
  22
  23 #include <asm/elf.h>
  24 #include <asm/tlb.h>
  25 #include <asm/tlbflush.h>
  26 #include "internal.h"
  27
  28 #define SEQ_PUT_DEC(str, val) \
  29                 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
  30 void task_mem(struct seq_file *m, struct mm_struct *mm)
  31 {
  32         unsigned long text, lib, swap, anon, file, shmem;
  33         unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
  34
  35         anon = get_mm_counter(mm, MM_ANONPAGES);
  36         file = get_mm_counter(mm, MM_FILEPAGES);
  37         shmem = get_mm_counter(mm, MM_SHMEMPAGES);
  38
  39         /*
  40          * Note: to minimize their overhead, mm maintains hiwater_vm and
  41          * hiwater_rss only when about to *lower* total_vm or rss.  Any
  42          * collector of these hiwater stats must therefore get total_vm
  43          * and rss too, which will usually be the higher.  Barriers? not
  44          * worth the effort, such snapshots can always be inconsistent.
  45          */
  46         hiwater_vm = total_vm = mm->total_vm;
  47         if (hiwater_vm < mm->hiwater_vm)
  48                 hiwater_vm = mm->hiwater_vm;
  49         hiwater_rss = total_rss = anon + file + shmem;
  50         if (hiwater_rss < mm->hiwater_rss)
  51                 hiwater_rss = mm->hiwater_rss;
  52
  53         /* split executable areas between text and lib */
  54         text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
  55         text = min(text, mm->exec_vm << PAGE_SHIFT);
  56         lib = (mm->exec_vm << PAGE_SHIFT) - text;
  57
  58         swap = get_mm_counter(mm, MM_SWAPENTS);
  59         SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
  60         SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
  61         SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
  62         SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm));
  63         SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
  64         SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
  65         SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
  66         SEQ_PUT_DEC(" kB\nRssFile:\t", file);
  67         SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
  68         SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
  69         SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
  70         seq_put_decimal_ull_width(m,
  71                     " kB\nVmExe:\t", text >> 10, 8);
  72         seq_put_decimal_ull_width(m,
  73                     " kB\nVmLib:\t", lib >> 10, 8);
  74         seq_put_decimal_ull_width(m,
  75                     " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
  76         SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
  77         seq_puts(m, " kB\n");
  78         hugetlb_report_usage(m, mm);
  79 }
  80 #undef SEQ_PUT_DEC
  81
  82 unsigned long task_vsize(struct mm_struct *mm)
  83 {
  84         return PAGE_SIZE * mm->total_vm;
  85 }
  86
  87 unsigned long task_statm(struct mm_struct *mm,
  88                          unsigned long *shared, unsigned long *text,
  89                          unsigned long *data, unsigned long *resident)
  90 {
  91         *shared = get_mm_counter(mm, MM_FILEPAGES) +
  92                         get_mm_counter(mm, MM_SHMEMPAGES);
  93         *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
  94                                                                 >> PAGE_SHIFT;
  95         *data = mm->data_vm + mm->stack_vm;
  96         *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
  97         return mm->total_vm;
  98 }
  99
 100 #ifdef CONFIG_NUMA
 101 /*
 102  * Save get_task_policy() for show_numa_map().
 103  */
 104 static void hold_task_mempolicy(struct proc_maps_private *priv)
 105 {
 106         struct task_struct *task = priv->task;
 107
 108         task_lock(task);
 109         priv->task_mempolicy = get_task_policy(task);
 110         mpol_get(priv->task_mempolicy);
 111         task_unlock(task);
 112 }
 113 static void release_task_mempolicy(struct proc_maps_private *priv)
 114 {
 115         mpol_put(priv->task_mempolicy);
 116 }
 117 #else
 118 static void hold_task_mempolicy(struct proc_maps_private *priv)
 119 {
 120 }
 121 static void release_task_mempolicy(struct proc_maps_private *priv)
 122 {
 123 }
 124 #endif
 125
 126 static void *m_start(struct seq_file *m, loff_t *ppos)
 127 {
 128         struct proc_maps_private *priv = m->private;
 129         unsigned long last_addr = *ppos;
 130         struct mm_struct *mm;
 131         struct vm_area_struct *vma;
 132
 133         /* See m_next(). Zero at the start or after lseek. */
 134         if (last_addr == -1UL)
 135                 return NULL;
 136
 137         priv->task = get_proc_task(priv->inode);
 138         if (!priv->task)
 139                 return ERR_PTR(-ESRCH);
 140
 141         mm = priv->mm;
 142         if (!mm || !mmget_not_zero(mm)) {
 143                 put_task_struct(priv->task);
 144                 priv->task = NULL;
 145                 return NULL;
 146         }
 147
 148         if (mmap_read_lock_killable(mm)) {
 149                 mmput(mm);
 150                 put_task_struct(priv->task);
 151                 priv->task = NULL;
 152                 return ERR_PTR(-EINTR);
 153         }
 154
 155         hold_task_mempolicy(priv);
 156         priv->tail_vma = get_gate_vma(mm);
 157
 158         vma = find_vma(mm, last_addr);
 159         if (vma)
 160                 return vma;
 161
 162         return priv->tail_vma;
 163 }
 164
 165 static void *m_next(struct seq_file *m, void *v, loff_t *ppos)
 166 {
 167         struct proc_maps_private *priv = m->private;
 168         struct vm_area_struct *next, *vma = v;
 169
 170         if (vma == priv->tail_vma)
 171                 next = NULL;
 172         else if (vma->vm_next)
 173                 next = vma->vm_next;
 174         else
 175                 next = priv->tail_vma;
 176
 177         *ppos = next ? next->vm_start : -1UL;
 178
 179         return next;
 180 }
 181
 182 static void m_stop(struct seq_file *m, void *v)
 183 {
 184         struct proc_maps_private *priv = m->private;
 185         struct mm_struct *mm = priv->mm;
 186
 187         if (!priv->task)
 188                 return;
 189
 190         release_task_mempolicy(priv);
 191         mmap_read_unlock(mm);
 192         mmput(mm);
 193         put_task_struct(priv->task);
 194         priv->task = NULL;
 195 }
 196
 197 static int proc_maps_open(struct inode *inode, struct file *file,
 198                         const struct seq_operations *ops, int psize)
 199 {
 200         struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
 201
 202         if (!priv)
 203                 return -ENOMEM;
 204
 205         priv->inode = inode;
 206         priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 207         if (IS_ERR(priv->mm)) {
 208                 int err = PTR_ERR(priv->mm);
 209
 210                 seq_release_private(inode, file);
 211                 return err;
 212         }
 213
 214         return 0;
 215 }
 216
 217 static int proc_map_release(struct inode *inode, struct file *file)
 218 {
 219         struct seq_file *seq = file->private_data;
 220         struct proc_maps_private *priv = seq->private;
 221
 222         if (priv->mm)
 223                 mmdrop(priv->mm);
 224
 225         return seq_release_private(inode, file);
 226 }
 227
 228 static int do_maps_open(struct inode *inode, struct file *file,
 229                         const struct seq_operations *ops)
 230 {
 231         return proc_maps_open(inode, file, ops,
 232                                 sizeof(struct proc_maps_private));
 233 }
 234
 235 /*
 236  * Indicate if the VMA is a stack for the given task; for
 237  * /proc/PID/maps that is the stack of the main task.
 238  */
 239 static int is_stack(struct vm_area_struct *vma)
 240 {
 241         /*
 242          * We make no effort to guess what a given thread considers to be
 243          * its "stack".  It's not even well-defined for programs written
 244          * languages like Go.
 245          */
 246         return vma->vm_start <= vma->vm_mm->start_stack &&
 247                 vma->vm_end >= vma->vm_mm->start_stack;
 248 }
 249
 250 static void show_vma_header_prefix(struct seq_file *m,
 251                                    unsigned long start, unsigned long end,
 252                                    vm_flags_t flags, unsigned long long pgoff,
 253                                    dev_t dev, unsigned long ino)
 254 {
 255         seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
 256         seq_put_hex_ll(m, NULL, start, 8);
 257         seq_put_hex_ll(m, "-", end, 8);
 258         seq_putc(m, ' ');
 259         seq_putc(m, flags & VM_READ ? 'r' : '-');
 260         seq_putc(m, flags & VM_WRITE ? 'w' : '-');
 261         seq_putc(m, flags & VM_EXEC ? 'x' : '-');
 262         seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
 263         seq_put_hex_ll(m, " ", pgoff, 8);
 264         seq_put_hex_ll(m, " ", MAJOR(dev), 2);
 265         seq_put_hex_ll(m, ":", MINOR(dev), 2);
 266         seq_put_decimal_ull(m, " ", ino);
 267         seq_putc(m, ' ');
 268 }
 269
 270 static void
 271 show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
 272 {
 273         struct mm_struct *mm = vma->vm_mm;
 274         struct file *file = vma->vm_file;
 275         vm_flags_t flags = vma->vm_flags;
 276         unsigned long ino = 0;
 277         unsigned long long pgoff = 0;
 278         unsigned long start, end;
 279         dev_t dev = 0;
 280         const char *name = NULL;
 281
 282         if (file) {
 283                 struct inode *inode = file_inode(vma->vm_file);
 284                 dev = inode->i_sb->s_dev;
 285                 ino = inode->i_ino;
 286                 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
 287         }
 288
 289         start = vma->vm_start;
 290         end = vma->vm_end;
 291         show_vma_header_prefix(m, start, end, flags, pgoff, 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_file_path(m, file, "\n");
 300                 goto done;
 301         }
 302
 303         if (vma->vm_ops && vma->vm_ops->name) {
 304                 name = vma->vm_ops->name(vma);
 305                 if (name)
 306                         goto done;
 307         }
 308
 309         name = arch_vma_name(vma);
 310         if (!name) {
 311                 if (!mm) {
 312                         name = "[vdso]";
 313                         goto done;
 314                 }
 315
 316                 if (vma->vm_start <= mm->brk &&
 317                     vma->vm_end >= mm->start_brk) {
 318                         name = "[heap]";
 319                         goto done;
 320                 }
 321
 322                 if (is_stack(vma))
 323                         name = "[stack]";
 324         }
 325
 326 done:
 327         if (name) {
 328                 seq_pad(m, ' ');
 329                 seq_puts(m, name);
 330         }
 331         seq_putc(m, '\n');
 332 }
 333
 334 static int show_map(struct seq_file *m, void *v)
 335 {
 336         show_map_vma(m, v);
 337         return 0;
 338 }
 339
 340 static const struct seq_operations proc_pid_maps_op = {
 341         .start  = m_start,
 342         .next   = m_next,
 343         .stop   = m_stop,
 344         .show   = show_map
 345 };
 346
 347 static int pid_maps_open(struct inode *inode, struct file *file)
 348 {
 349         return do_maps_open(inode, file, &proc_pid_maps_op);
 350 }
 351
 352 const struct file_operations proc_pid_maps_operations = {
 353         .open           = pid_maps_open,
 354         .read           = seq_read,
 355         .llseek         = seq_lseek,
 356         .release        = proc_map_release,
 357 };
 358
 359 /*
 360  * Proportional Set Size(PSS): my share of RSS.
 361  *
 362  * PSS of a process is the count of pages it has in memory, where each
 363  * page is divided by the number of processes sharing it.  So if a
 364  * process has 1000 pages all to itself, and 1000 shared with one other
 365  * process, its PSS will be 1500.
 366  *
 367  * To keep (accumulated) division errors low, we adopt a 64bit
 368  * fixed-point pss counter to minimize division errors. So (pss >>
 369  * PSS_SHIFT) would be the real byte count.
 370  *
 371  * A shift of 12 before division means (assuming 4K page size):
 372  *      - 1M 3-user-pages add up to 8KB errors;
 373  *      - supports mapcount up to 2^24, or 16M;
 374  *      - supports PSS up to 2^52 bytes, or 4PB.
 375  */
 376 #define PSS_SHIFT 12
 377
 378 #ifdef CONFIG_PROC_PAGE_MONITOR
 379 struct mem_size_stats {
 380         unsigned long resident;
 381         unsigned long shared_clean;
 382         unsigned long shared_dirty;
 383         unsigned long private_clean;
 384         unsigned long private_dirty;
 385         unsigned long referenced;
 386         unsigned long anonymous;
 387         unsigned long lazyfree;
 388         unsigned long anonymous_thp;
 389         unsigned long shmem_thp;
 390         unsigned long file_thp;
 391         unsigned long swap;
 392         unsigned long shared_hugetlb;
 393         unsigned long private_hugetlb;
 394         u64 pss;
 395         u64 pss_anon;
 396         u64 pss_file;
 397         u64 pss_shmem;
 398         u64 pss_locked;
 399         u64 swap_pss;
 400         bool check_shmem_swap;
 401 };
 402
 403 static void smaps_page_accumulate(struct mem_size_stats *mss,
 404                 struct page *page, unsigned long size, unsigned long pss,
 405                 bool dirty, bool locked, bool private)
 406 {
 407         mss->pss += pss;
 408
 409         if (PageAnon(page))
 410                 mss->pss_anon += pss;
 411         else if (PageSwapBacked(page))
 412                 mss->pss_shmem += pss;
 413         else
 414                 mss->pss_file += pss;
 415
 416         if (locked)
 417                 mss->pss_locked += pss;
 418
 419         if (dirty || PageDirty(page)) {
 420                 if (private)
 421                         mss->private_dirty += size;
 422                 else
 423                         mss->shared_dirty += size;
 424         } else {
 425                 if (private)
 426                         mss->private_clean += size;
 427                 else
 428                         mss->shared_clean += size;
 429         }
 430 }
 431
 432 static void smaps_account(struct mem_size_stats *mss, struct page *page,
 433                 bool compound, bool young, bool dirty, bool locked)
 434 {
 435         int i, nr = compound ? compound_nr(page) : 1;
 436         unsigned long size = nr * PAGE_SIZE;
 437
 438         /*
 439          * First accumulate quantities that depend only on |size| and the type
 440          * of the compound page.
 441          */
 442         if (PageAnon(page)) {
 443                 mss->anonymous += size;
 444                 if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
 445                         mss->lazyfree += size;
 446         }
 447
 448         mss->resident += size;
 449         /* Accumulate the size in pages that have been accessed. */
 450         if (young || page_is_young(page) || PageReferenced(page))
 451                 mss->referenced += size;
 452
 453         /*
 454          * Then accumulate quantities that may depend on sharing, or that may
 455          * differ page-by-page.
 456          *
 457          * page_count(page) == 1 guarantees the page is mapped exactly once.
 458          * If any subpage of the compound page mapped with PTE it would elevate
 459          * page_count().
 460          */
 461         if (page_count(page) == 1) {
 462                 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
 463                         locked, true);
 464                 return;
 465         }
 466         for (i = 0; i < nr; i++, page++) {
 467                 int mapcount = page_mapcount(page);
 468                 unsigned long pss = PAGE_SIZE << PSS_SHIFT;
 469                 if (mapcount >= 2)
 470                         pss /= mapcount;
 471                 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
 472                                       mapcount < 2);
 473         }
 474 }
 475
 476 #ifdef CONFIG_SHMEM
 477 static int smaps_pte_hole(unsigned long addr, unsigned long end,
 478                           __always_unused int depth, struct mm_walk *walk)
 479 {
 480         struct mem_size_stats *mss = walk->private;
 481
 482         mss->swap += shmem_partial_swap_usage(
 483                         walk->vma->vm_file->f_mapping, addr, end);
 484
 485         return 0;
 486 }
 487 #else
 488 #define smaps_pte_hole          NULL
 489 #endif /* CONFIG_SHMEM */
 490
 491 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 492                 struct mm_walk *walk)
 493 {
 494         struct mem_size_stats *mss = walk->private;
 495         struct vm_area_struct *vma = walk->vma;
 496         bool locked = !!(vma->vm_flags & VM_LOCKED);
 497         struct page *page = NULL;
 498
 499         if (pte_present(*pte)) {
 500                 page = vm_normal_page(vma, addr, *pte);
 501         } else if (is_swap_pte(*pte)) {
 502                 swp_entry_t swpent = pte_to_swp_entry(*pte);
 503
 504                 if (!non_swap_entry(swpent)) {
 505                         int mapcount;
 506
 507                         mss->swap += PAGE_SIZE;
 508                         mapcount = swp_swapcount(swpent);
 509                         if (mapcount >= 2) {
 510                                 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
 511
 512                                 do_div(pss_delta, mapcount);
 513                                 mss->swap_pss += pss_delta;
 514                         } else {
 515                                 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 516                         }
 517                 } else if (is_migration_entry(swpent))
 518                         page = migration_entry_to_page(swpent);
 519                 else if (is_device_private_entry(swpent))
 520                         page = device_private_entry_to_page(swpent);
 521         } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
 522                                                         && pte_none(*pte))) {
 523                 page = xa_load(&vma->vm_file->f_mapping->i_pages,
 524                                                 linear_page_index(vma, addr));
 525                 if (xa_is_value(page))
 526                         mss->swap += PAGE_SIZE;
 527                 return;
 528         }
 529
 530         if (!page)
 531                 return;
 532
 533         smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked);
 534 }
 535
 536 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 537 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 538                 struct mm_walk *walk)
 539 {
 540         struct mem_size_stats *mss = walk->private;
 541         struct vm_area_struct *vma = walk->vma;
 542         bool locked = !!(vma->vm_flags & VM_LOCKED);
 543         struct page *page = NULL;
 544
 545         if (pmd_present(*pmd)) {
 546                 /* FOLL_DUMP will return -EFAULT on huge zero page */
 547                 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
 548         } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
 549                 swp_entry_t entry = pmd_to_swp_entry(*pmd);
 550
 551                 if (is_migration_entry(entry))
 552                         page = migration_entry_to_page(entry);
 553         }
 554         if (IS_ERR_OR_NULL(page))
 555                 return;
 556         if (PageAnon(page))
 557                 mss->anonymous_thp += HPAGE_PMD_SIZE;
 558         else if (PageSwapBacked(page))
 559                 mss->shmem_thp += HPAGE_PMD_SIZE;
 560         else if (is_zone_device_page(page))
 561                 /* pass */;
 562         else
 563                 mss->file_thp += HPAGE_PMD_SIZE;
 564         smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked);
 565 }
 566 #else
 567 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 568                 struct mm_walk *walk)
 569 {
 570 }
 571 #endif
 572
 573 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 574                            struct mm_walk *walk)
 575 {
 576         struct vm_area_struct *vma = walk->vma;
 577         pte_t *pte;
 578         spinlock_t *ptl;
 579
 580         ptl = pmd_trans_huge_lock(pmd, vma);
 581         if (ptl) {
 582                 smaps_pmd_entry(pmd, addr, walk);
 583                 spin_unlock(ptl);
 584                 goto out;
 585         }
 586
 587         if (pmd_trans_unstable(pmd))
 588                 goto out;
 589         /*
 590          * The mmap_lock held all the way back in m_start() is what
 591          * keeps khugepaged out of here and from collapsing things
 592          * in here.
 593          */
 594         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 595         for (; addr != end; pte++, addr += PAGE_SIZE)
 596                 smaps_pte_entry(pte, addr, walk);
 597         pte_unmap_unlock(pte - 1, ptl);
 598 out:
 599         cond_resched();
 600         return 0;
 601 }
 602
 603 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 604 {
 605         /*
 606          * Don't forget to update Documentation/ on changes.
 607          */
 608         static const char mnemonics[BITS_PER_LONG][2] = {
 609                 /*
 610                  * In case if we meet a flag we don't know about.
 611                  */
 612                 [0 ... (BITS_PER_LONG-1)] = "??",
 613
 614                 [ilog2(VM_READ)]        = "rd",
 615                 [ilog2(VM_WRITE)]       = "wr",
 616                 [ilog2(VM_EXEC)]        = "ex",
 617                 [ilog2(VM_SHARED)]      = "sh",
 618                 [ilog2(VM_MAYREAD)]     = "mr",
 619                 [ilog2(VM_MAYWRITE)]    = "mw",
 620                 [ilog2(VM_MAYEXEC)]     = "me",
 621                 [ilog2(VM_MAYSHARE)]    = "ms",
 622                 [ilog2(VM_GROWSDOWN)]   = "gd",
 623                 [ilog2(VM_PFNMAP)]      = "pf",
 624                 [ilog2(VM_DENYWRITE)]   = "dw",
 625                 [ilog2(VM_LOCKED)]      = "lo",
 626                 [ilog2(VM_IO)]          = "io",
 627                 [ilog2(VM_SEQ_READ)]    = "sr",
 628                 [ilog2(VM_RAND_READ)]   = "rr",
 629                 [ilog2(VM_DONTCOPY)]    = "dc",
 630                 [ilog2(VM_DONTEXPAND)]  = "de",
 631                 [ilog2(VM_ACCOUNT)]     = "ac",
 632                 [ilog2(VM_NORESERVE)]   = "nr",
 633                 [ilog2(VM_HUGETLB)]     = "ht",
 634                 [ilog2(VM_SYNC)]        = "sf",
 635                 [ilog2(VM_ARCH_1)]      = "ar",
 636                 [ilog2(VM_WIPEONFORK)]  = "wf",
 637                 [ilog2(VM_DONTDUMP)]    = "dd",
 638 #ifdef CONFIG_ARM64_BTI
 639                 [ilog2(VM_ARM64_BTI)]   = "bt",
 640 #endif
 641 #ifdef CONFIG_MEM_SOFT_DIRTY
 642                 [ilog2(VM_SOFTDIRTY)]   = "sd",
 643 #endif
 644                 [ilog2(VM_MIXEDMAP)]    = "mm",
 645                 [ilog2(VM_HUGEPAGE)]    = "hg",
 646                 [ilog2(VM_NOHUGEPAGE)]  = "nh",
 647                 [ilog2(VM_MERGEABLE)]   = "mg",
 648                 [ilog2(VM_UFFD_MISSING)]= "um",
 649                 [ilog2(VM_UFFD_WP)]     = "uw",
 650 #ifdef CONFIG_ARM64_MTE
 651                 [ilog2(VM_MTE)]         = "mt",
 652                 [ilog2(VM_MTE_ALLOWED)] = "",
 653 #endif
 654 #ifdef CONFIG_ARCH_HAS_PKEYS
 655                 /* These come out via ProtectionKey: */
 656                 [ilog2(VM_PKEY_BIT0)]   = "",
 657                 [ilog2(VM_PKEY_BIT1)]   = "",
 658                 [ilog2(VM_PKEY_BIT2)]   = "",
 659                 [ilog2(VM_PKEY_BIT3)]   = "",
 660 #if VM_PKEY_BIT4
 661                 [ilog2(VM_PKEY_BIT4)]   = "",
 662 #endif
 663 #endif /* CONFIG_ARCH_HAS_PKEYS */
 664         };
 665         size_t i;
 666
 667         seq_puts(m, "VmFlags: ");
 668         for (i = 0; i < BITS_PER_LONG; i++) {
 669                 if (!mnemonics[i][0])
 670                         continue;
 671                 if (vma->vm_flags & (1UL << i)) {
 672                         seq_putc(m, mnemonics[i][0]);
 673                         seq_putc(m, mnemonics[i][1]);
 674                         seq_putc(m, ' ');
 675                 }
 676         }
 677         seq_putc(m, '\n');
 678 }
 679
 680 #ifdef CONFIG_HUGETLB_PAGE
 681 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 682                                  unsigned long addr, unsigned long end,
 683                                  struct mm_walk *walk)
 684 {
 685         struct mem_size_stats *mss = walk->private;
 686         struct vm_area_struct *vma = walk->vma;
 687         struct page *page = NULL;
 688
 689         if (pte_present(*pte)) {
 690                 page = vm_normal_page(vma, addr, *pte);
 691         } else if (is_swap_pte(*pte)) {
 692                 swp_entry_t swpent = pte_to_swp_entry(*pte);
 693
 694                 if (is_migration_entry(swpent))
 695                         page = migration_entry_to_page(swpent);
 696                 else if (is_device_private_entry(swpent))
 697                         page = device_private_entry_to_page(swpent);
 698         }
 699         if (page) {
 700                 int mapcount = page_mapcount(page);
 701
 702                 if (mapcount >= 2)
 703                         mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
 704                 else
 705                         mss->private_hugetlb += huge_page_size(hstate_vma(vma));
 706         }
 707         return 0;
 708 }
 709 #else
 710 #define smaps_hugetlb_range     NULL
 711 #endif /* HUGETLB_PAGE */
 712
 713 static const struct mm_walk_ops smaps_walk_ops = {
 714         .pmd_entry              = smaps_pte_range,
 715         .hugetlb_entry          = smaps_hugetlb_range,
 716 };
 717
 718 static const struct mm_walk_ops smaps_shmem_walk_ops = {
 719         .pmd_entry              = smaps_pte_range,
 720         .hugetlb_entry          = smaps_hugetlb_range,
 721         .pte_hole               = smaps_pte_hole,
 722 };
 723
 724 /*
 725  * Gather mem stats from @vma with the indicated beginning
 726  * address @start, and keep them in @mss.
 727  *
 728  * Use vm_start of @vma as the beginning address if @start is 0.
 729  */
 730 static void smap_gather_stats(struct vm_area_struct *vma,
 731                 struct mem_size_stats *mss, unsigned long start)
 732 {
 733         const struct mm_walk_ops *ops = &smaps_walk_ops;
 734
 735         /* Invalid start */
 736         if (start >= vma->vm_end)
 737                 return;
 738
 739 #ifdef CONFIG_SHMEM
 740         /* In case of smaps_rollup, reset the value from previous vma */
 741         mss->check_shmem_swap = false;
 742         if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
 743                 /*
 744                  * For shared or readonly shmem mappings we know that all
 745                  * swapped out pages belong to the shmem object, and we can
 746                  * obtain the swap value much more efficiently. For private
 747                  * writable mappings, we might have COW pages that are
 748                  * not affected by the parent swapped out pages of the shmem
 749                  * object, so we have to distinguish them during the page walk.
 750                  * Unless we know that the shmem object (or the part mapped by
 751                  * our VMA) has no swapped out pages at all.
 752                  */
 753                 unsigned long shmem_swapped = shmem_swap_usage(vma);
 754
 755                 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
 756                                         !(vma->vm_flags & VM_WRITE))) {
 757                         mss->swap += shmem_swapped;
 758                 } else {
 759                         mss->check_shmem_swap = true;
 760                         ops = &smaps_shmem_walk_ops;
 761                 }
 762         }
 763 #endif
 764         /* mmap_lock is held in m_start */
 765         if (!start)
 766                 walk_page_vma(vma, ops, mss);
 767         else
 768                 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
 769 }
 770
 771 #define SEQ_PUT_DEC(str, val) \
 772                 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 773
 774 /* Show the contents common for smaps and smaps_rollup */
 775 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
 776         bool rollup_mode)
 777 {
 778         SEQ_PUT_DEC("Rss:            ", mss->resident);
 779         SEQ_PUT_DEC(" kB\nPss:            ", mss->pss >> PSS_SHIFT);
 780         if (rollup_mode) {
 781                 /*
 782                  * These are meaningful only for smaps_rollup, otherwise two of
 783                  * them are zero, and the other one is the same as Pss.
 784                  */
 785                 SEQ_PUT_DEC(" kB\nPss_Anon:       ",
 786                         mss->pss_anon >> PSS_SHIFT);
 787                 SEQ_PUT_DEC(" kB\nPss_File:       ",
 788                         mss->pss_file >> PSS_SHIFT);
 789                 SEQ_PUT_DEC(" kB\nPss_Shmem:      ",
 790                         mss->pss_shmem >> PSS_SHIFT);
 791         }
 792         SEQ_PUT_DEC(" kB\nShared_Clean:   ", mss->shared_clean);
 793         SEQ_PUT_DEC(" kB\nShared_Dirty:   ", mss->shared_dirty);
 794         SEQ_PUT_DEC(" kB\nPrivate_Clean:  ", mss->private_clean);
 795         SEQ_PUT_DEC(" kB\nPrivate_Dirty:  ", mss->private_dirty);
 796         SEQ_PUT_DEC(" kB\nReferenced:     ", mss->referenced);
 797         SEQ_PUT_DEC(" kB\nAnonymous:      ", mss->anonymous);
 798         SEQ_PUT_DEC(" kB\nLazyFree:       ", mss->lazyfree);
 799         SEQ_PUT_DEC(" kB\nAnonHugePages:  ", mss->anonymous_thp);
 800         SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
 801         SEQ_PUT_DEC(" kB\nFilePmdMapped:  ", mss->file_thp);
 802         SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
 803         seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
 804                                   mss->private_hugetlb >> 10, 7);
 805         SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 806         SEQ_PUT_DEC(" kB\nSwapPss:        ",
 807                                         mss->swap_pss >> PSS_SHIFT);
 808         SEQ_PUT_DEC(" kB\nLocked:         ",
 809                                         mss->pss_locked >> PSS_SHIFT);
 810         seq_puts(m, " kB\n");
 811 }
 812
 813 static int show_smap(struct seq_file *m, void *v)
 814 {
 815         struct vm_area_struct *vma = v;
 816         struct mem_size_stats mss;
 817
 818         memset(&mss, 0, sizeof(mss));
 819
 820         smap_gather_stats(vma, &mss, 0);
 821
 822         show_map_vma(m, vma);
 823
 824         SEQ_PUT_DEC("Size:           ", vma->vm_end - vma->vm_start);
 825         SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
 826         SEQ_PUT_DEC(" kB\nMMUPageSize:    ", vma_mmu_pagesize(vma));
 827         seq_puts(m, " kB\n");
 828
 829         __show_smap(m, &mss, false);
 830
 831         seq_printf(m, "THPeligible:    %d\n",
 832                    transparent_hugepage_enabled(vma));
 833
 834         if (arch_pkeys_enabled())
 835                 seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
 836         show_smap_vma_flags(m, vma);
 837
 838         return 0;
 839 }
 840
 841 static int show_smaps_rollup(struct seq_file *m, void *v)
 842 {
 843         struct proc_maps_private *priv = m->private;
 844         struct mem_size_stats mss;
 845         struct mm_struct *mm;
 846         struct vm_area_struct *vma;
 847         unsigned long last_vma_end = 0;
 848         int ret = 0;
 849
 850         priv->task = get_proc_task(priv->inode);
 851         if (!priv->task)
 852                 return -ESRCH;
 853
 854         mm = priv->mm;
 855         if (!mm || !mmget_not_zero(mm)) {
 856                 ret = -ESRCH;
 857                 goto out_put_task;
 858         }
 859
 860         memset(&mss, 0, sizeof(mss));
 861
 862         ret = mmap_read_lock_killable(mm);
 863         if (ret)
 864                 goto out_put_mm;
 865
 866         hold_task_mempolicy(priv);
 867
 868         for (vma = priv->mm->mmap; vma;) {
 869                 smap_gather_stats(vma, &mss, 0);
 870                 last_vma_end = vma->vm_end;
 871
 872                 /*
 873                  * Release mmap_lock temporarily if someone wants to
 874                  * access it for write request.
 875                  */
 876                 if (mmap_lock_is_contended(mm)) {
 877                         mmap_read_unlock(mm);
 878                         ret = mmap_read_lock_killable(mm);
 879                         if (ret) {
 880                                 release_task_mempolicy(priv);
 881                                 goto out_put_mm;
 882                         }
 883
 884                         /*
 885                          * After dropping the lock, there are four cases to
 886                          * consider. See the following example for explanation.
 887                          *
 888                          *   +------+------+-----------+
 889                          *   | VMA1 | VMA2 | VMA3      |
 890                          *   +------+------+-----------+
 891                          *   |      |      |           |
 892                          *  4k     8k     16k         400k
 893                          *
 894                          * Suppose we drop the lock after reading VMA2 due to
 895                          * contention, then we get:
 896                          *
 897                          *      last_vma_end = 16k
 898                          *
 899                          * 1) VMA2 is freed, but VMA3 exists:
 900                          *
 901                          *    find_vma(mm, 16k - 1) will return VMA3.
 902                          *    In this case, just continue from VMA3.
 903                          *
 904                          * 2) VMA2 still exists:
 905                          *
 906                          *    find_vma(mm, 16k - 1) will return VMA2.
 907                          *    Iterate the loop like the original one.
 908                          *
 909                          * 3) No more VMAs can be found:
 910                          *
 911                          *    find_vma(mm, 16k - 1) will return NULL.
 912                          *    No more things to do, just break.
 913                          *
 914                          * 4) (last_vma_end - 1) is the middle of a vma (VMA'):
 915                          *
 916                          *    find_vma(mm, 16k - 1) will return VMA' whose range
 917                          *    contains last_vma_end.
 918                          *    Iterate VMA' from last_vma_end.
 919                          */
 920                         vma = find_vma(mm, last_vma_end - 1);
 921                         /* Case 3 above */
 922                         if (!vma)
 923                                 break;
 924
 925                         /* Case 1 above */
 926                         if (vma->vm_start >= last_vma_end)
 927                                 continue;
 928
 929                         /* Case 4 above */
 930                         if (vma->vm_end > last_vma_end)
 931                                 smap_gather_stats(vma, &mss, last_vma_end);
 932                 }
 933                 /* Case 2 above */
 934                 vma = vma->vm_next;
 935         }
 936
 937         show_vma_header_prefix(m, priv->mm->mmap->vm_start,
 938                                last_vma_end, 0, 0, 0, 0);
 939         seq_pad(m, ' ');
 940         seq_puts(m, "[rollup]\n");
 941
 942         __show_smap(m, &mss, true);
 943
 944         release_task_mempolicy(priv);
 945         mmap_read_unlock(mm);
 946
 947 out_put_mm:
 948         mmput(mm);
 949 out_put_task:
 950         put_task_struct(priv->task);
 951         priv->task = NULL;
 952
 953         return ret;
 954 }
 955 #undef SEQ_PUT_DEC
 956
 957 static const struct seq_operations proc_pid_smaps_op = {
 958         .start  = m_start,
 959         .next   = m_next,
 960         .stop   = m_stop,
 961         .show   = show_smap
 962 };
 963
 964 static int pid_smaps_open(struct inode *inode, struct file *file)
 965 {
 966         return do_maps_open(inode, file, &proc_pid_smaps_op);
 967 }
 968
 969 static int smaps_rollup_open(struct inode *inode, struct file *file)
 970 {
 971         int ret;
 972         struct proc_maps_private *priv;
 973
 974         priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
 975         if (!priv)
 976                 return -ENOMEM;
 977
 978         ret = single_open(file, show_smaps_rollup, priv);
 979         if (ret)
 980                 goto out_free;
 981
 982         priv->inode = inode;
 983         priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 984         if (IS_ERR(priv->mm)) {
 985                 ret = PTR_ERR(priv->mm);
 986
 987                 single_release(inode, file);
 988                 goto out_free;
 989         }
 990
 991         return 0;
 992
 993 out_free:
 994         kfree(priv);
 995         return ret;
 996 }
 997
 998 static int smaps_rollup_release(struct inode *inode, struct file *file)
 999 {
1000         struct seq_file *seq = file->private_data;
1001         struct proc_maps_private *priv = seq->private;
1002
1003         if (priv->mm)
1004                 mmdrop(priv->mm);
1005
1006         kfree(priv);
1007         return single_release(inode, file);
1008 }
1009
1010 const struct file_operations proc_pid_smaps_operations = {
1011         .open           = pid_smaps_open,
1012         .read           = seq_read,
1013         .llseek         = seq_lseek,
1014         .release        = proc_map_release,
1015 };
1016
1017 const struct file_operations proc_pid_smaps_rollup_operations = {
1018         .open           = smaps_rollup_open,
1019         .read           = seq_read,
1020         .llseek         = seq_lseek,
1021         .release        = smaps_rollup_release,
1022 };
1023
1024 enum clear_refs_types {
1025         CLEAR_REFS_ALL = 1,
1026         CLEAR_REFS_ANON,
1027         CLEAR_REFS_MAPPED,
1028         CLEAR_REFS_SOFT_DIRTY,
1029         CLEAR_REFS_MM_HIWATER_RSS,
1030         CLEAR_REFS_LAST,
1031 };
1032
1033 struct clear_refs_private {
1034         enum clear_refs_types type;
1035 };
1036
1037 #ifdef CONFIG_MEM_SOFT_DIRTY
1038
1039 static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1040 {
1041         struct page *page;
1042
1043         if (!pte_write(pte))
1044                 return false;
1045         if (!is_cow_mapping(vma->vm_flags))
1046                 return false;
1047         if (likely(!atomic_read(&vma->vm_mm->has_pinned)))
1048                 return false;
1049         page = vm_normal_page(vma, addr, pte);
1050         if (!page)
1051                 return false;
1052         return page_maybe_dma_pinned(page);
1053 }
1054
1055 static inline void clear_soft_dirty(struct vm_area_struct *vma,
1056                 unsigned long addr, pte_t *pte)
1057 {
1058         /*
1059          * The soft-dirty tracker uses #PF-s to catch writes
1060          * to pages, so write-protect the pte as well. See the
1061          * Documentation/admin-guide/mm/soft-dirty.rst for full description
1062          * of how soft-dirty works.
1063          */
1064         pte_t ptent = *pte;
1065
1066         if (pte_present(ptent)) {
1067                 pte_t old_pte;
1068
1069                 if (pte_is_pinned(vma, addr, ptent))
1070                         return;
1071                 old_pte = ptep_modify_prot_start(vma, addr, pte);
1072                 ptent = pte_wrprotect(old_pte);
1073                 ptent = pte_clear_soft_dirty(ptent);
1074                 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1075         } else if (is_swap_pte(ptent)) {
1076                 ptent = pte_swp_clear_soft_dirty(ptent);
1077                 set_pte_at(vma->vm_mm, addr, pte, ptent);
1078         }
1079 }
1080 #else
1081 static inline void clear_soft_dirty(struct vm_area_struct *vma,
1082                 unsigned long addr, pte_t *pte)
1083 {
1084 }
1085 #endif
1086
1087 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1088 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1089                 unsigned long addr, pmd_t *pmdp)
1090 {
1091         pmd_t old, pmd = *pmdp;
1092
1093         if (pmd_present(pmd)) {
1094                 /* See comment in change_huge_pmd() */
1095                 old = pmdp_invalidate(vma, addr, pmdp);
1096                 if (pmd_dirty(old))
1097                         pmd = pmd_mkdirty(pmd);
1098                 if (pmd_young(old))
1099                         pmd = pmd_mkyoung(pmd);
1100
1101                 pmd = pmd_wrprotect(pmd);
1102                 pmd = pmd_clear_soft_dirty(pmd);
1103
1104                 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1105         } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1106                 pmd = pmd_swp_clear_soft_dirty(pmd);
1107                 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1108         }
1109 }
1110 #else
1111 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1112                 unsigned long addr, pmd_t *pmdp)
1113 {
1114 }
1115 #endif
1116
1117 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1118                                 unsigned long end, struct mm_walk *walk)
1119 {
1120         struct clear_refs_private *cp = walk->private;
1121         struct vm_area_struct *vma = walk->vma;
1122         pte_t *pte, ptent;
1123         spinlock_t *ptl;
1124         struct page *page;
1125
1126         ptl = pmd_trans_huge_lock(pmd, vma);
1127         if (ptl) {
1128                 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1129                         clear_soft_dirty_pmd(vma, addr, pmd);
1130                         goto out;
1131                 }
1132
1133                 if (!pmd_present(*pmd))
1134                         goto out;
1135
1136                 page = pmd_page(*pmd);
1137
1138                 /* Clear accessed and referenced bits. */
1139                 pmdp_test_and_clear_young(vma, addr, pmd);
1140                 test_and_clear_page_young(page);
1141                 ClearPageReferenced(page);
1142 out:
1143                 spin_unlock(ptl);
1144                 return 0;
1145         }
1146
1147         if (pmd_trans_unstable(pmd))
1148                 return 0;
1149
1150         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1151         for (; addr != end; pte++, addr += PAGE_SIZE) {
1152                 ptent = *pte;
1153
1154                 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1155                         clear_soft_dirty(vma, addr, pte);
1156                         continue;
1157                 }
1158
1159                 if (!pte_present(ptent))
1160                         continue;
1161
1162                 page = vm_normal_page(vma, addr, ptent);
1163                 if (!page)
1164                         continue;
1165
1166                 /* Clear accessed and referenced bits. */
1167                 ptep_test_and_clear_young(vma, addr, pte);
1168                 test_and_clear_page_young(page);
1169                 ClearPageReferenced(page);
1170         }
1171         pte_unmap_unlock(pte - 1, ptl);
1172         cond_resched();
1173         return 0;
1174 }
1175
1176 static int clear_refs_test_walk(unsigned long start, unsigned long end,
1177                                 struct mm_walk *walk)
1178 {
1179         struct clear_refs_private *cp = walk->private;
1180         struct vm_area_struct *vma = walk->vma;
1181
1182         if (vma->vm_flags & VM_PFNMAP)
1183                 return 1;
1184
1185         /*
1186          * Writing 1 to /proc/pid/clear_refs affects all pages.
1187          * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1188          * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1189          * Writing 4 to /proc/pid/clear_refs affects all pages.
1190          */
1191         if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1192                 return 1;
1193         if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1194                 return 1;
1195         return 0;
1196 }
1197
1198 static const struct mm_walk_ops clear_refs_walk_ops = {
1199         .pmd_entry              = clear_refs_pte_range,
1200         .test_walk              = clear_refs_test_walk,
1201 };
1202
1203 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1204                                 size_t count, loff_t *ppos)
1205 {
1206         struct task_struct *task;
1207         char buffer[PROC_NUMBUF];
1208         struct mm_struct *mm;
1209         struct vm_area_struct *vma;
1210         enum clear_refs_types type;
1211         int itype;
1212         int rv;
1213
1214         memset(buffer, 0, sizeof(buffer));
1215         if (count > sizeof(buffer) - 1)
1216                 count = sizeof(buffer) - 1;
1217         if (copy_from_user(buffer, buf, count))
1218                 return -EFAULT;
1219         rv = kstrtoint(strstrip(buffer), 10, &itype);
1220         if (rv < 0)
1221                 return rv;
1222         type = (enum clear_refs_types)itype;
1223         if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1224                 return -EINVAL;
1225
1226         task = get_proc_task(file_inode(file));
1227         if (!task)
1228                 return -ESRCH;
1229         mm = get_task_mm(task);
1230         if (mm) {
1231                 struct mmu_notifier_range range;
1232                 struct clear_refs_private cp = {
1233                         .type = type,
1234                 };
1235
1236                 if (mmap_write_lock_killable(mm)) {
1237                         count = -EINTR;
1238                         goto out_mm;
1239                 }
1240                 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1241                         /*
1242                          * Writing 5 to /proc/pid/clear_refs resets the peak
1243                          * resident set size to this mm's current rss value.
1244                          */
1245                         reset_mm_hiwater_rss(mm);
1246                         goto out_unlock;
1247                 }
1248
1249                 if (type == CLEAR_REFS_SOFT_DIRTY) {
1250                         for (vma = mm->mmap; vma; vma = vma->vm_next) {
1251                                 if (!(vma->vm_flags & VM_SOFTDIRTY))
1252                                         continue;
1253                                 vma->vm_flags &= ~VM_SOFTDIRTY;
1254                                 vma_set_page_prot(vma);
1255                         }
1256
1257                         inc_tlb_flush_pending(mm);
1258                         mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1259                                                 0, NULL, mm, 0, -1UL);
1260                         mmu_notifier_invalidate_range_start(&range);
1261                 }
1262                 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops,
1263                                 &cp);
1264                 if (type == CLEAR_REFS_SOFT_DIRTY) {
1265                         mmu_notifier_invalidate_range_end(&range);
1266                         flush_tlb_mm(mm);
1267                         dec_tlb_flush_pending(mm);
1268                 }
1269 out_unlock:
1270                 mmap_write_unlock(mm);
1271 out_mm:
1272                 mmput(mm);
1273         }
1274         put_task_struct(task);
1275
1276         return count;
1277 }
1278
1279 const struct file_operations proc_clear_refs_operations = {
1280         .write          = clear_refs_write,
1281         .llseek         = noop_llseek,
1282 };
1283
1284 typedef struct {
1285         u64 pme;
1286 } pagemap_entry_t;
1287
1288 struct pagemapread {
1289         int pos, len;           /* units: PM_ENTRY_BYTES, not bytes */
1290         pagemap_entry_t *buffer;
1291         bool show_pfn;
1292 };
1293
1294 #define PAGEMAP_WALK_SIZE       (PMD_SIZE)
1295 #define PAGEMAP_WALK_MASK       (PMD_MASK)
1296
1297 #define PM_ENTRY_BYTES          sizeof(pagemap_entry_t)
1298 #define PM_PFRAME_BITS          55
1299 #define PM_PFRAME_MASK          GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1300 #define PM_SOFT_DIRTY           BIT_ULL(55)
1301 #define PM_MMAP_EXCLUSIVE       BIT_ULL(56)
1302 #define PM_FILE                 BIT_ULL(61)
1303 #define PM_SWAP                 BIT_ULL(62)
1304 #define PM_PRESENT              BIT_ULL(63)
1305
1306 #define PM_END_OF_BUFFER    1
1307
1308 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1309 {
1310         return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1311 }
1312
1313 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1314                           struct pagemapread *pm)
1315 {
1316         pm->buffer[pm->pos++] = *pme;
1317         if (pm->pos >= pm->len)
1318                 return PM_END_OF_BUFFER;
1319         return 0;
1320 }
1321
1322 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1323                             __always_unused int depth, struct mm_walk *walk)
1324 {
1325         struct pagemapread *pm = walk->private;
1326         unsigned long addr = start;
1327         int err = 0;
1328
1329         while (addr < end) {
1330                 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1331                 pagemap_entry_t pme = make_pme(0, 0);
1332                 /* End of address space hole, which we mark as non-present. */
1333                 unsigned long hole_end;
1334
1335                 if (vma)
1336                         hole_end = min(end, vma->vm_start);
1337                 else
1338                         hole_end = end;
1339
1340                 for (; addr < hole_end; addr += PAGE_SIZE) {
1341                         err = add_to_pagemap(addr, &pme, pm);
1342                         if (err)
1343                                 goto out;
1344                 }
1345
1346                 if (!vma)
1347                         break;
1348
1349                 /* Addresses in the VMA. */
1350                 if (vma->vm_flags & VM_SOFTDIRTY)
1351                         pme = make_pme(0, PM_SOFT_DIRTY);
1352                 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1353                         err = add_to_pagemap(addr, &pme, pm);
1354                         if (err)
1355                                 goto out;
1356                 }
1357         }
1358 out:
1359         return err;
1360 }
1361
1362 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1363                 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1364 {
1365         u64 frame = 0, flags = 0;
1366         struct page *page = NULL;
1367
1368         if (pte_present(pte)) {
1369                 if (pm->show_pfn)
1370                         frame = pte_pfn(pte);
1371                 flags |= PM_PRESENT;
1372                 page = vm_normal_page(vma, addr, pte);
1373                 if (pte_soft_dirty(pte))
1374                         flags |= PM_SOFT_DIRTY;
1375         } else if (is_swap_pte(pte)) {
1376                 swp_entry_t entry;
1377                 if (pte_swp_soft_dirty(pte))
1378                         flags |= PM_SOFT_DIRTY;
1379                 entry = pte_to_swp_entry(pte);
1380                 if (pm->show_pfn)
1381                         frame = swp_type(entry) |
1382                                 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1383                 flags |= PM_SWAP;
1384                 if (is_migration_entry(entry))
1385                         page = migration_entry_to_page(entry);
1386
1387                 if (is_device_private_entry(entry))
1388                         page = device_private_entry_to_page(entry);
1389         }
1390
1391         if (page && !PageAnon(page))
1392                 flags |= PM_FILE;
1393         if (page && page_mapcount(page) == 1)
1394                 flags |= PM_MMAP_EXCLUSIVE;
1395         if (vma->vm_flags & VM_SOFTDIRTY)
1396                 flags |= PM_SOFT_DIRTY;
1397
1398         return make_pme(frame, flags);
1399 }
1400
1401 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1402                              struct mm_walk *walk)
1403 {
1404         struct vm_area_struct *vma = walk->vma;
1405         struct pagemapread *pm = walk->private;
1406         spinlock_t *ptl;
1407         pte_t *pte, *orig_pte;
1408         int err = 0;
1409
1410 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1411         ptl = pmd_trans_huge_lock(pmdp, vma);
1412         if (ptl) {
1413                 u64 flags = 0, frame = 0;
1414                 pmd_t pmd = *pmdp;
1415                 struct page *page = NULL;
1416
1417                 if (vma->vm_flags & VM_SOFTDIRTY)
1418                         flags |= PM_SOFT_DIRTY;
1419
1420                 if (pmd_present(pmd)) {
1421                         page = pmd_page(pmd);
1422
1423                         flags |= PM_PRESENT;
1424                         if (pmd_soft_dirty(pmd))
1425                                 flags |= PM_SOFT_DIRTY;
1426                         if (pm->show_pfn)
1427                                 frame = pmd_pfn(pmd) +
1428                                         ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1429                 }
1430 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1431                 else if (is_swap_pmd(pmd)) {
1432                         swp_entry_t entry = pmd_to_swp_entry(pmd);
1433                         unsigned long offset;
1434
1435                         if (pm->show_pfn) {
1436                                 offset = swp_offset(entry) +
1437                                         ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1438                                 frame = swp_type(entry) |
1439                                         (offset << MAX_SWAPFILES_SHIFT);
1440                         }
1441                         flags |= PM_SWAP;
1442                         if (pmd_swp_soft_dirty(pmd))
1443                                 flags |= PM_SOFT_DIRTY;
1444                         VM_BUG_ON(!is_pmd_migration_entry(pmd));
1445                         page = migration_entry_to_page(entry);
1446                 }
1447 #endif
1448
1449                 if (page && page_mapcount(page) == 1)
1450                         flags |= PM_MMAP_EXCLUSIVE;
1451
1452                 for (; addr != end; addr += PAGE_SIZE) {
1453                         pagemap_entry_t pme = make_pme(frame, flags);
1454
1455                         err = add_to_pagemap(addr, &pme, pm);
1456                         if (err)
1457                                 break;
1458                         if (pm->show_pfn) {
1459                                 if (flags & PM_PRESENT)
1460                                         frame++;
1461                                 else if (flags & PM_SWAP)
1462                                         frame += (1 << MAX_SWAPFILES_SHIFT);
1463                         }
1464                 }
1465                 spin_unlock(ptl);
1466                 return err;
1467         }
1468
1469         if (pmd_trans_unstable(pmdp))
1470                 return 0;
1471 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1472
1473         /*
1474          * We can assume that @vma always points to a valid one and @end never
1475          * goes beyond vma->vm_end.
1476          */
1477         orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1478         for (; addr < end; pte++, addr += PAGE_SIZE) {
1479                 pagemap_entry_t pme;
1480
1481                 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1482                 err = add_to_pagemap(addr, &pme, pm);
1483                 if (err)
1484                         break;
1485         }
1486         pte_unmap_unlock(orig_pte, ptl);
1487
1488         cond_resched();
1489
1490         return err;
1491 }
1492
1493 #ifdef CONFIG_HUGETLB_PAGE
1494 /* This function walks within one hugetlb entry in the single call */
1495 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1496                                  unsigned long addr, unsigned long end,
1497                                  struct mm_walk *walk)
1498 {
1499         struct pagemapread *pm = walk->private;
1500         struct vm_area_struct *vma = walk->vma;
1501         u64 flags = 0, frame = 0;
1502         int err = 0;
1503         pte_t pte;
1504
1505         if (vma->vm_flags & VM_SOFTDIRTY)
1506                 flags |= PM_SOFT_DIRTY;
1507
1508         pte = huge_ptep_get(ptep);
1509         if (pte_present(pte)) {
1510                 struct page *page = pte_page(pte);
1511
1512                 if (!PageAnon(page))
1513                         flags |= PM_FILE;
1514
1515                 if (page_mapcount(page) == 1)
1516                         flags |= PM_MMAP_EXCLUSIVE;
1517
1518                 flags |= PM_PRESENT;
1519                 if (pm->show_pfn)
1520                         frame = pte_pfn(pte) +
1521                                 ((addr & ~hmask) >> PAGE_SHIFT);
1522         }
1523
1524         for (; addr != end; addr += PAGE_SIZE) {
1525                 pagemap_entry_t pme = make_pme(frame, flags);
1526
1527                 err = add_to_pagemap(addr, &pme, pm);
1528                 if (err)
1529                         return err;
1530                 if (pm->show_pfn && (flags & PM_PRESENT))
1531                         frame++;
1532         }
1533
1534         cond_resched();
1535
1536         return err;
1537 }
1538 #else
1539 #define pagemap_hugetlb_range   NULL
1540 #endif /* HUGETLB_PAGE */
1541
1542 static const struct mm_walk_ops pagemap_ops = {
1543         .pmd_entry      = pagemap_pmd_range,
1544         .pte_hole       = pagemap_pte_hole,
1545         .hugetlb_entry  = pagemap_hugetlb_range,
1546 };
1547
1548 /*
1549  * /proc/pid/pagemap - an array mapping virtual pages to pfns
1550  *
1551  * For each page in the address space, this file contains one 64-bit entry
1552  * consisting of the following:
1553  *
1554  * Bits 0-54  page frame number (PFN) if present
1555  * Bits 0-4   swap type if swapped
1556  * Bits 5-54  swap offset if swapped
1557  * Bit  55    pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1558  * Bit  56    page exclusively mapped
1559  * Bits 57-60 zero
1560  * Bit  61    page is file-page or shared-anon
1561  * Bit  62    page swapped
1562  * Bit  63    page present
1563  *
1564  * If the page is not present but in swap, then the PFN contains an
1565  * encoding of the swap file number and the page's offset into the
1566  * swap. Unmapped pages return a null PFN. This allows determining
1567  * precisely which pages are mapped (or in swap) and comparing mapped
1568  * pages between processes.
1569  *
1570  * Efficient users of this interface will use /proc/pid/maps to
1571  * determine which areas of memory are actually mapped and llseek to
1572  * skip over unmapped regions.
1573  */
1574 static ssize_t pagemap_read(struct file *file, char __user *buf,
1575                             size_t count, loff_t *ppos)
1576 {
1577         struct mm_struct *mm = file->private_data;
1578         struct pagemapread pm;
1579         unsigned long src;
1580         unsigned long svpfn;
1581         unsigned long start_vaddr;
1582         unsigned long end_vaddr;
1583         int ret = 0, copied = 0;
1584
1585         if (!mm || !mmget_not_zero(mm))
1586                 goto out;
1587
1588         ret = -EINVAL;
1589         /* file position must be aligned */
1590         if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1591                 goto out_mm;
1592
1593         ret = 0;
1594         if (!count)
1595                 goto out_mm;
1596
1597         /* do not disclose physical addresses: attack vector */
1598         pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1599
1600         pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1601         pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1602         ret = -ENOMEM;
1603         if (!pm.buffer)
1604                 goto out_mm;
1605
1606         src = *ppos;
1607         svpfn = src / PM_ENTRY_BYTES;
1608         end_vaddr = mm->task_size;
1609
1610         /* watch out for wraparound */
1611         start_vaddr = end_vaddr;
1612         if (svpfn <= (ULONG_MAX >> PAGE_SHIFT))
1613                 start_vaddr = untagged_addr(svpfn << PAGE_SHIFT);
1614
1615         /* Ensure the address is inside the task */
1616         if (start_vaddr > mm->task_size)
1617                 start_vaddr = end_vaddr;
1618
1619         /*
1620          * The odds are that this will stop walking way
1621          * before end_vaddr, because the length of the
1622          * user buffer is tracked in "pm", and the walk
1623          * will stop when we hit the end of the buffer.
1624          */
1625         ret = 0;
1626         while (count && (start_vaddr < end_vaddr)) {
1627                 int len;
1628                 unsigned long end;
1629
1630                 pm.pos = 0;
1631                 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1632                 /* overflow ? */
1633                 if (end < start_vaddr || end > end_vaddr)
1634                         end = end_vaddr;
1635                 ret = mmap_read_lock_killable(mm);
1636                 if (ret)
1637                         goto out_free;
1638                 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1639                 mmap_read_unlock(mm);
1640                 start_vaddr = end;
1641
1642                 len = min(count, PM_ENTRY_BYTES * pm.pos);
1643                 if (copy_to_user(buf, pm.buffer, len)) {
1644                         ret = -EFAULT;
1645                         goto out_free;
1646                 }
1647                 copied += len;
1648                 buf += len;
1649                 count -= len;
1650         }
1651         *ppos += copied;
1652         if (!ret || ret == PM_END_OF_BUFFER)
1653                 ret = copied;
1654
1655 out_free:
1656         kfree(pm.buffer);
1657 out_mm:
1658         mmput(mm);
1659 out:
1660         return ret;
1661 }
1662
1663 static int pagemap_open(struct inode *inode, struct file *file)
1664 {
1665         struct mm_struct *mm;
1666
1667         mm = proc_mem_open(inode, PTRACE_MODE_READ);
1668         if (IS_ERR(mm))
1669                 return PTR_ERR(mm);
1670         file->private_data = mm;
1671         return 0;
1672 }
1673
1674 static int pagemap_release(struct inode *inode, struct file *file)
1675 {
1676         struct mm_struct *mm = file->private_data;
1677
1678         if (mm)
1679                 mmdrop(mm);
1680         return 0;
1681 }
1682
1683 const struct file_operations proc_pagemap_operations = {
1684         .llseek         = mem_lseek, /* borrow this */
1685         .read           = pagemap_read,
1686         .open           = pagemap_open,
1687         .release        = pagemap_release,
1688 };
1689 #endif /* CONFIG_PROC_PAGE_MONITOR */
1690
1691 #ifdef CONFIG_NUMA
1692
1693 struct numa_maps {
1694         unsigned long pages;
1695         unsigned long anon;
1696         unsigned long active;
1697         unsigned long writeback;
1698         unsigned long mapcount_max;
1699         unsigned long dirty;
1700         unsigned long swapcache;
1701         unsigned long node[MAX_NUMNODES];
1702 };
1703
1704 struct numa_maps_private {
1705         struct proc_maps_private proc_maps;
1706         struct numa_maps md;
1707 };
1708
1709 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1710                         unsigned long nr_pages)
1711 {
1712         int count = page_mapcount(page);
1713
1714         md->pages += nr_pages;
1715         if (pte_dirty || PageDirty(page))
1716                 md->dirty += nr_pages;
1717
1718         if (PageSwapCache(page))
1719                 md->swapcache += nr_pages;
1720
1721         if (PageActive(page) || PageUnevictable(page))
1722                 md->active += nr_pages;
1723
1724         if (PageWriteback(page))
1725                 md->writeback += nr_pages;
1726
1727         if (PageAnon(page))
1728                 md->anon += nr_pages;
1729
1730         if (count > md->mapcount_max)
1731                 md->mapcount_max = count;
1732
1733         md->node[page_to_nid(page)] += nr_pages;
1734 }
1735
1736 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1737                 unsigned long addr)
1738 {
1739         struct page *page;
1740         int nid;
1741
1742         if (!pte_present(pte))
1743                 return NULL;
1744
1745         page = vm_normal_page(vma, addr, pte);
1746         if (!page)
1747                 return NULL;
1748
1749         if (PageReserved(page))
1750                 return NULL;
1751
1752         nid = page_to_nid(page);
1753         if (!node_isset(nid, node_states[N_MEMORY]))
1754                 return NULL;
1755
1756         return page;
1757 }
1758
1759 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1760 static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1761                                               struct vm_area_struct *vma,
1762                                               unsigned long addr)
1763 {
1764         struct page *page;
1765         int nid;
1766
1767         if (!pmd_present(pmd))
1768                 return NULL;
1769
1770         page = vm_normal_page_pmd(vma, addr, pmd);
1771         if (!page)
1772                 return NULL;
1773
1774         if (PageReserved(page))
1775                 return NULL;
1776
1777         nid = page_to_nid(page);
1778         if (!node_isset(nid, node_states[N_MEMORY]))
1779                 return NULL;
1780
1781         return page;
1782 }
1783 #endif
1784
1785 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1786                 unsigned long end, struct mm_walk *walk)
1787 {
1788         struct numa_maps *md = walk->private;
1789         struct vm_area_struct *vma = walk->vma;
1790         spinlock_t *ptl;
1791         pte_t *orig_pte;
1792         pte_t *pte;
1793
1794 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1795         ptl = pmd_trans_huge_lock(pmd, vma);
1796         if (ptl) {
1797                 struct page *page;
1798
1799                 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1800                 if (page)
1801                         gather_stats(page, md, pmd_dirty(*pmd),
1802                                      HPAGE_PMD_SIZE/PAGE_SIZE);
1803                 spin_unlock(ptl);
1804                 return 0;
1805         }
1806
1807         if (pmd_trans_unstable(pmd))
1808                 return 0;
1809 #endif
1810         orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1811         do {
1812                 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1813                 if (!page)
1814                         continue;
1815                 gather_stats(page, md, pte_dirty(*pte), 1);
1816
1817         } while (pte++, addr += PAGE_SIZE, addr != end);
1818         pte_unmap_unlock(orig_pte, ptl);
1819         cond_resched();
1820         return 0;
1821 }
1822 #ifdef CONFIG_HUGETLB_PAGE
1823 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1824                 unsigned long addr, unsigned long end, struct mm_walk *walk)
1825 {
1826         pte_t huge_pte = huge_ptep_get(pte);
1827         struct numa_maps *md;
1828         struct page *page;
1829
1830         if (!pte_present(huge_pte))
1831                 return 0;
1832
1833         page = pte_page(huge_pte);
1834         if (!page)
1835                 return 0;
1836
1837         md = walk->private;
1838         gather_stats(page, md, pte_dirty(huge_pte), 1);
1839         return 0;
1840 }
1841
1842 #else
1843 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1844                 unsigned long addr, unsigned long end, struct mm_walk *walk)
1845 {
1846         return 0;
1847 }
1848 #endif
1849
1850 static const struct mm_walk_ops show_numa_ops = {
1851         .hugetlb_entry = gather_hugetlb_stats,
1852         .pmd_entry = gather_pte_stats,
1853 };
1854
1855 /*
1856  * Display pages allocated per node and memory policy via /proc.
1857  */
1858 static int show_numa_map(struct seq_file *m, void *v)
1859 {
1860         struct numa_maps_private *numa_priv = m->private;
1861         struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1862         struct vm_area_struct *vma = v;
1863         struct numa_maps *md = &numa_priv->md;
1864         struct file *file = vma->vm_file;
1865         struct mm_struct *mm = vma->vm_mm;
1866         struct mempolicy *pol;
1867         char buffer[64];
1868         int nid;
1869
1870         if (!mm)
1871                 return 0;
1872
1873         /* Ensure we start with an empty set of numa_maps statistics. */
1874         memset(md, 0, sizeof(*md));
1875
1876         pol = __get_vma_policy(vma, vma->vm_start);
1877         if (pol) {
1878                 mpol_to_str(buffer, sizeof(buffer), pol);
1879                 mpol_cond_put(pol);
1880         } else {
1881                 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1882         }
1883
1884         seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1885
1886         if (file) {
1887                 seq_puts(m, " file=");
1888                 seq_file_path(m, file, "\n\t= ");
1889         } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1890                 seq_puts(m, " heap");
1891         } else if (is_stack(vma)) {
1892                 seq_puts(m, " stack");
1893         }
1894
1895         if (is_vm_hugetlb_page(vma))
1896                 seq_puts(m, " huge");
1897
1898         /* mmap_lock is held by m_start */
1899         walk_page_vma(vma, &show_numa_ops, md);
1900
1901         if (!md->pages)
1902                 goto out;
1903
1904         if (md->anon)
1905                 seq_printf(m, " anon=%lu", md->anon);
1906
1907         if (md->dirty)
1908                 seq_printf(m, " dirty=%lu", md->dirty);
1909
1910         if (md->pages != md->anon && md->pages != md->dirty)
1911                 seq_printf(m, " mapped=%lu", md->pages);
1912
1913         if (md->mapcount_max > 1)
1914                 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1915
1916         if (md->swapcache)
1917                 seq_printf(m, " swapcache=%lu", md->swapcache);
1918
1919         if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1920                 seq_printf(m, " active=%lu", md->active);
1921
1922         if (md->writeback)
1923                 seq_printf(m, " writeback=%lu", md->writeback);
1924
1925         for_each_node_state(nid, N_MEMORY)
1926                 if (md->node[nid])
1927                         seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1928
1929         seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1930 out:
1931         seq_putc(m, '\n');
1932         return 0;
1933 }
1934
1935 static const struct seq_operations proc_pid_numa_maps_op = {
1936         .start  = m_start,
1937         .next   = m_next,
1938         .stop   = m_stop,
1939         .show   = show_numa_map,
1940 };
1941
1942 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1943 {
1944         return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
1945                                 sizeof(struct numa_maps_private));
1946 }
1947
1948 const struct file_operations proc_pid_numa_maps_operations = {
1949         .open           = pid_numa_maps_open,
1950         .read           = seq_read,
1951         .llseek         = seq_lseek,
1952         .release        = proc_map_release,
1953 };
1954
1955 #endif /* CONFIG_NUMA */