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 };
 401
 402 static void smaps_page_accumulate(struct mem_size_stats *mss,
 403                 struct page *page, unsigned long size, unsigned long pss,
 404                 bool dirty, bool locked, bool private)
 405 {
 406         mss->pss += pss;
 407
 408         if (PageAnon(page))
 409                 mss->pss_anon += pss;
 410         else if (PageSwapBacked(page))
 411                 mss->pss_shmem += pss;
 412         else
 413                 mss->pss_file += pss;
 414
 415         if (locked)
 416                 mss->pss_locked += pss;
 417
 418         if (dirty || PageDirty(page)) {
 419                 if (private)
 420                         mss->private_dirty += size;
 421                 else
 422                         mss->shared_dirty += size;
 423         } else {
 424                 if (private)
 425                         mss->private_clean += size;
 426                 else
 427                         mss->shared_clean += size;
 428         }
 429 }
 430
 431 static void smaps_account(struct mem_size_stats *mss, struct page *page,
 432                 bool compound, bool young, bool dirty, bool locked)
 433 {
 434         int i, nr = compound ? compound_nr(page) : 1;
 435         unsigned long size = nr * PAGE_SIZE;
 436
 437         /*
 438          * First accumulate quantities that depend only on |size| and the type
 439          * of the compound page.
 440          */
 441         if (PageAnon(page)) {
 442                 mss->anonymous += size;
 443                 if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
 444                         mss->lazyfree += size;
 445         }
 446
 447         mss->resident += size;
 448         /* Accumulate the size in pages that have been accessed. */
 449         if (young || page_is_young(page) || PageReferenced(page))
 450                 mss->referenced += size;
 451
 452         /*
 453          * Then accumulate quantities that may depend on sharing, or that may
 454          * differ page-by-page.
 455          *
 456          * page_count(page) == 1 guarantees the page is mapped exactly once.
 457          * If any subpage of the compound page mapped with PTE it would elevate
 458          * page_count().
 459          */
 460         if (page_count(page) == 1) {
 461                 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
 462                         locked, true);
 463                 return;
 464         }
 465         for (i = 0; i < nr; i++, page++) {
 466                 int mapcount = page_mapcount(page);
 467                 unsigned long pss = PAGE_SIZE << PSS_SHIFT;
 468                 if (mapcount >= 2)
 469                         pss /= mapcount;
 470                 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
 471                                       mapcount < 2);
 472         }
 473 }
 474
 475 #ifdef CONFIG_SHMEM
 476 static int smaps_pte_hole(unsigned long addr, unsigned long end,
 477                           __always_unused int depth, struct mm_walk *walk)
 478 {
 479         struct mem_size_stats *mss = walk->private;
 480         struct vm_area_struct *vma = walk->vma;
 481
 482         mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping,
 483                                               linear_page_index(vma, addr),
 484                                               linear_page_index(vma, end));
 485
 486         return 0;
 487 }
 488 #else
 489 #define smaps_pte_hole          NULL
 490 #endif /* CONFIG_SHMEM */
 491
 492 static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk)
 493 {
 494 #ifdef CONFIG_SHMEM
 495         if (walk->ops->pte_hole) {
 496                 /* depth is not used */
 497                 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk);
 498         }
 499 #endif
 500 }
 501
 502 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 503                 struct mm_walk *walk)
 504 {
 505         struct mem_size_stats *mss = walk->private;
 506         struct vm_area_struct *vma = walk->vma;
 507         bool locked = !!(vma->vm_flags & VM_LOCKED);
 508         struct page *page = NULL;
 509
 510         if (pte_present(*pte)) {
 511                 page = vm_normal_page(vma, addr, *pte);
 512         } else if (is_swap_pte(*pte)) {
 513                 swp_entry_t swpent = pte_to_swp_entry(*pte);
 514
 515                 if (!non_swap_entry(swpent)) {
 516                         int mapcount;
 517
 518                         mss->swap += PAGE_SIZE;
 519                         mapcount = swp_swapcount(swpent);
 520                         if (mapcount >= 2) {
 521                                 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
 522
 523                                 do_div(pss_delta, mapcount);
 524                                 mss->swap_pss += pss_delta;
 525                         } else {
 526                                 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 527                         }
 528                 } else if (is_pfn_swap_entry(swpent))
 529                         page = pfn_swap_entry_to_page(swpent);
 530         } else {
 531                 smaps_pte_hole_lookup(addr, walk);
 532                 return;
 533         }
 534
 535         if (!page)
 536                 return;
 537
 538         smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked);
 539 }
 540
 541 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 542 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 543                 struct mm_walk *walk)
 544 {
 545         struct mem_size_stats *mss = walk->private;
 546         struct vm_area_struct *vma = walk->vma;
 547         bool locked = !!(vma->vm_flags & VM_LOCKED);
 548         struct page *page = NULL;
 549
 550         if (pmd_present(*pmd)) {
 551                 /* FOLL_DUMP will return -EFAULT on huge zero page */
 552                 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
 553         } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
 554                 swp_entry_t entry = pmd_to_swp_entry(*pmd);
 555
 556                 if (is_migration_entry(entry))
 557                         page = pfn_swap_entry_to_page(entry);
 558         }
 559         if (IS_ERR_OR_NULL(page))
 560                 return;
 561         if (PageAnon(page))
 562                 mss->anonymous_thp += HPAGE_PMD_SIZE;
 563         else if (PageSwapBacked(page))
 564                 mss->shmem_thp += HPAGE_PMD_SIZE;
 565         else if (is_zone_device_page(page))
 566                 /* pass */;
 567         else
 568                 mss->file_thp += HPAGE_PMD_SIZE;
 569         smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked);
 570 }
 571 #else
 572 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 573                 struct mm_walk *walk)
 574 {
 575 }
 576 #endif
 577
 578 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 579                            struct mm_walk *walk)
 580 {
 581         struct vm_area_struct *vma = walk->vma;
 582         pte_t *pte;
 583         spinlock_t *ptl;
 584
 585         ptl = pmd_trans_huge_lock(pmd, vma);
 586         if (ptl) {
 587                 smaps_pmd_entry(pmd, addr, walk);
 588                 spin_unlock(ptl);
 589                 goto out;
 590         }
 591
 592         if (pmd_trans_unstable(pmd))
 593                 goto out;
 594         /*
 595          * The mmap_lock held all the way back in m_start() is what
 596          * keeps khugepaged out of here and from collapsing things
 597          * in here.
 598          */
 599         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 600         for (; addr != end; pte++, addr += PAGE_SIZE)
 601                 smaps_pte_entry(pte, addr, walk);
 602         pte_unmap_unlock(pte - 1, ptl);
 603 out:
 604         cond_resched();
 605         return 0;
 606 }
 607
 608 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 609 {
 610         /*
 611          * Don't forget to update Documentation/ on changes.
 612          */
 613         static const char mnemonics[BITS_PER_LONG][2] = {
 614                 /*
 615                  * In case if we meet a flag we don't know about.
 616                  */
 617                 [0 ... (BITS_PER_LONG-1)] = "??",
 618
 619                 [ilog2(VM_READ)]        = "rd",
 620                 [ilog2(VM_WRITE)]       = "wr",
 621                 [ilog2(VM_EXEC)]        = "ex",
 622                 [ilog2(VM_SHARED)]      = "sh",
 623                 [ilog2(VM_MAYREAD)]     = "mr",
 624                 [ilog2(VM_MAYWRITE)]    = "mw",
 625                 [ilog2(VM_MAYEXEC)]     = "me",
 626                 [ilog2(VM_MAYSHARE)]    = "ms",
 627                 [ilog2(VM_GROWSDOWN)]   = "gd",
 628                 [ilog2(VM_PFNMAP)]      = "pf",
 629                 [ilog2(VM_LOCKED)]      = "lo",
 630                 [ilog2(VM_IO)]          = "io",
 631                 [ilog2(VM_SEQ_READ)]    = "sr",
 632                 [ilog2(VM_RAND_READ)]   = "rr",
 633                 [ilog2(VM_DONTCOPY)]    = "dc",
 634                 [ilog2(VM_DONTEXPAND)]  = "de",
 635                 [ilog2(VM_ACCOUNT)]     = "ac",
 636                 [ilog2(VM_NORESERVE)]   = "nr",
 637                 [ilog2(VM_HUGETLB)]     = "ht",
 638                 [ilog2(VM_SYNC)]        = "sf",
 639                 [ilog2(VM_ARCH_1)]      = "ar",
 640                 [ilog2(VM_WIPEONFORK)]  = "wf",
 641                 [ilog2(VM_DONTDUMP)]    = "dd",
 642 #ifdef CONFIG_ARM64_BTI
 643                 [ilog2(VM_ARM64_BTI)]   = "bt",
 644 #endif
 645 #ifdef CONFIG_MEM_SOFT_DIRTY
 646                 [ilog2(VM_SOFTDIRTY)]   = "sd",
 647 #endif
 648                 [ilog2(VM_MIXEDMAP)]    = "mm",
 649                 [ilog2(VM_HUGEPAGE)]    = "hg",
 650                 [ilog2(VM_NOHUGEPAGE)]  = "nh",
 651                 [ilog2(VM_MERGEABLE)]   = "mg",
 652                 [ilog2(VM_UFFD_MISSING)]= "um",
 653                 [ilog2(VM_UFFD_WP)]     = "uw",
 654 #ifdef CONFIG_ARM64_MTE
 655                 [ilog2(VM_MTE)]         = "mt",
 656                 [ilog2(VM_MTE_ALLOWED)] = "",
 657 #endif
 658 #ifdef CONFIG_ARCH_HAS_PKEYS
 659                 /* These come out via ProtectionKey: */
 660                 [ilog2(VM_PKEY_BIT0)]   = "",
 661                 [ilog2(VM_PKEY_BIT1)]   = "",
 662                 [ilog2(VM_PKEY_BIT2)]   = "",
 663                 [ilog2(VM_PKEY_BIT3)]   = "",
 664 #if VM_PKEY_BIT4
 665                 [ilog2(VM_PKEY_BIT4)]   = "",
 666 #endif
 667 #endif /* CONFIG_ARCH_HAS_PKEYS */
 668 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
 669                 [ilog2(VM_UFFD_MINOR)]  = "ui",
 670 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
 671         };
 672         size_t i;
 673
 674         seq_puts(m, "VmFlags: ");
 675         for (i = 0; i < BITS_PER_LONG; i++) {
 676                 if (!mnemonics[i][0])
 677                         continue;
 678                 if (vma->vm_flags & (1UL << i)) {
 679                         seq_putc(m, mnemonics[i][0]);
 680                         seq_putc(m, mnemonics[i][1]);
 681                         seq_putc(m, ' ');
 682                 }
 683         }
 684         seq_putc(m, '\n');
 685 }
 686
 687 #ifdef CONFIG_HUGETLB_PAGE
 688 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 689                                  unsigned long addr, unsigned long end,
 690                                  struct mm_walk *walk)
 691 {
 692         struct mem_size_stats *mss = walk->private;
 693         struct vm_area_struct *vma = walk->vma;
 694         struct page *page = NULL;
 695
 696         if (pte_present(*pte)) {
 697                 page = vm_normal_page(vma, addr, *pte);
 698         } else if (is_swap_pte(*pte)) {
 699                 swp_entry_t swpent = pte_to_swp_entry(*pte);
 700
 701                 if (is_pfn_swap_entry(swpent))
 702                         page = pfn_swap_entry_to_page(swpent);
 703         }
 704         if (page) {
 705                 int mapcount = page_mapcount(page);
 706
 707                 if (mapcount >= 2)
 708                         mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
 709                 else
 710                         mss->private_hugetlb += huge_page_size(hstate_vma(vma));
 711         }
 712         return 0;
 713 }
 714 #else
 715 #define smaps_hugetlb_range     NULL
 716 #endif /* HUGETLB_PAGE */
 717
 718 static const struct mm_walk_ops smaps_walk_ops = {
 719         .pmd_entry              = smaps_pte_range,
 720         .hugetlb_entry          = smaps_hugetlb_range,
 721 };
 722
 723 static const struct mm_walk_ops smaps_shmem_walk_ops = {
 724         .pmd_entry              = smaps_pte_range,
 725         .hugetlb_entry          = smaps_hugetlb_range,
 726         .pte_hole               = smaps_pte_hole,
 727 };
 728
 729 /*
 730  * Gather mem stats from @vma with the indicated beginning
 731  * address @start, and keep them in @mss.
 732  *
 733  * Use vm_start of @vma as the beginning address if @start is 0.
 734  */
 735 static void smap_gather_stats(struct vm_area_struct *vma,
 736                 struct mem_size_stats *mss, unsigned long start)
 737 {
 738         const struct mm_walk_ops *ops = &smaps_walk_ops;
 739
 740         /* Invalid start */
 741         if (start >= vma->vm_end)
 742                 return;
 743
 744 #ifdef CONFIG_SHMEM
 745         if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
 746                 /*
 747                  * For shared or readonly shmem mappings we know that all
 748                  * swapped out pages belong to the shmem object, and we can
 749                  * obtain the swap value much more efficiently. For private
 750                  * writable mappings, we might have COW pages that are
 751                  * not affected by the parent swapped out pages of the shmem
 752                  * object, so we have to distinguish them during the page walk.
 753                  * Unless we know that the shmem object (or the part mapped by
 754                  * our VMA) has no swapped out pages at all.
 755                  */
 756                 unsigned long shmem_swapped = shmem_swap_usage(vma);
 757
 758                 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
 759                                         !(vma->vm_flags & VM_WRITE))) {
 760                         mss->swap += shmem_swapped;
 761                 } else {
 762                         ops = &smaps_shmem_walk_ops;
 763                 }
 764         }
 765 #endif
 766         /* mmap_lock is held in m_start */
 767         if (!start)
 768                 walk_page_vma(vma, ops, mss);
 769         else
 770                 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
 771 }
 772
 773 #define SEQ_PUT_DEC(str, val) \
 774                 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 775
 776 /* Show the contents common for smaps and smaps_rollup */
 777 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
 778         bool rollup_mode)
 779 {
 780         SEQ_PUT_DEC("Rss:            ", mss->resident);
 781         SEQ_PUT_DEC(" kB\nPss:            ", mss->pss >> PSS_SHIFT);
 782         if (rollup_mode) {
 783                 /*
 784                  * These are meaningful only for smaps_rollup, otherwise two of
 785                  * them are zero, and the other one is the same as Pss.
 786                  */
 787                 SEQ_PUT_DEC(" kB\nPss_Anon:       ",
 788                         mss->pss_anon >> PSS_SHIFT);
 789                 SEQ_PUT_DEC(" kB\nPss_File:       ",
 790                         mss->pss_file >> PSS_SHIFT);
 791                 SEQ_PUT_DEC(" kB\nPss_Shmem:      ",
 792                         mss->pss_shmem >> PSS_SHIFT);
 793         }
 794         SEQ_PUT_DEC(" kB\nShared_Clean:   ", mss->shared_clean);
 795         SEQ_PUT_DEC(" kB\nShared_Dirty:   ", mss->shared_dirty);
 796         SEQ_PUT_DEC(" kB\nPrivate_Clean:  ", mss->private_clean);
 797         SEQ_PUT_DEC(" kB\nPrivate_Dirty:  ", mss->private_dirty);
 798         SEQ_PUT_DEC(" kB\nReferenced:     ", mss->referenced);
 799         SEQ_PUT_DEC(" kB\nAnonymous:      ", mss->anonymous);
 800         SEQ_PUT_DEC(" kB\nLazyFree:       ", mss->lazyfree);
 801         SEQ_PUT_DEC(" kB\nAnonHugePages:  ", mss->anonymous_thp);
 802         SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
 803         SEQ_PUT_DEC(" kB\nFilePmdMapped:  ", mss->file_thp);
 804         SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
 805         seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
 806                                   mss->private_hugetlb >> 10, 7);
 807         SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 808         SEQ_PUT_DEC(" kB\nSwapPss:        ",
 809                                         mss->swap_pss >> PSS_SHIFT);
 810         SEQ_PUT_DEC(" kB\nLocked:         ",
 811                                         mss->pss_locked >> PSS_SHIFT);
 812         seq_puts(m, " kB\n");
 813 }
 814
 815 static int show_smap(struct seq_file *m, void *v)
 816 {
 817         struct vm_area_struct *vma = v;
 818         struct mem_size_stats mss;
 819
 820         memset(&mss, 0, sizeof(mss));
 821
 822         smap_gather_stats(vma, &mss, 0);
 823
 824         show_map_vma(m, vma);
 825
 826         SEQ_PUT_DEC("Size:           ", vma->vm_end - vma->vm_start);
 827         SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
 828         SEQ_PUT_DEC(" kB\nMMUPageSize:    ", vma_mmu_pagesize(vma));
 829         seq_puts(m, " kB\n");
 830
 831         __show_smap(m, &mss, false);
 832
 833         seq_printf(m, "THPeligible:    %d\n",
 834                    transparent_hugepage_active(vma));
 835
 836         if (arch_pkeys_enabled())
 837                 seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
 838         show_smap_vma_flags(m, vma);
 839
 840         return 0;
 841 }
 842
 843 static int show_smaps_rollup(struct seq_file *m, void *v)
 844 {
 845         struct proc_maps_private *priv = m->private;
 846         struct mem_size_stats mss;
 847         struct mm_struct *mm;
 848         struct vm_area_struct *vma;
 849         unsigned long last_vma_end = 0;
 850         int ret = 0;
 851
 852         priv->task = get_proc_task(priv->inode);
 853         if (!priv->task)
 854                 return -ESRCH;
 855
 856         mm = priv->mm;
 857         if (!mm || !mmget_not_zero(mm)) {
 858                 ret = -ESRCH;
 859                 goto out_put_task;
 860         }
 861
 862         memset(&mss, 0, sizeof(mss));
 863
 864         ret = mmap_read_lock_killable(mm);
 865         if (ret)
 866                 goto out_put_mm;
 867
 868         hold_task_mempolicy(priv);
 869
 870         for (vma = priv->mm->mmap; vma;) {
 871                 smap_gather_stats(vma, &mss, 0);
 872                 last_vma_end = vma->vm_end;
 873
 874                 /*
 875                  * Release mmap_lock temporarily if someone wants to
 876                  * access it for write request.
 877                  */
 878                 if (mmap_lock_is_contended(mm)) {
 879                         mmap_read_unlock(mm);
 880                         ret = mmap_read_lock_killable(mm);
 881                         if (ret) {
 882                                 release_task_mempolicy(priv);
 883                                 goto out_put_mm;
 884                         }
 885
 886                         /*
 887                          * After dropping the lock, there are four cases to
 888                          * consider. See the following example for explanation.
 889                          *
 890                          *   +------+------+-----------+
 891                          *   | VMA1 | VMA2 | VMA3      |
 892                          *   +------+------+-----------+
 893                          *   |      |      |           |
 894                          *  4k     8k     16k         400k
 895                          *
 896                          * Suppose we drop the lock after reading VMA2 due to
 897                          * contention, then we get:
 898                          *
 899                          *      last_vma_end = 16k
 900                          *
 901                          * 1) VMA2 is freed, but VMA3 exists:
 902                          *
 903                          *    find_vma(mm, 16k - 1) will return VMA3.
 904                          *    In this case, just continue from VMA3.
 905                          *
 906                          * 2) VMA2 still exists:
 907                          *
 908                          *    find_vma(mm, 16k - 1) will return VMA2.
 909                          *    Iterate the loop like the original one.
 910                          *
 911                          * 3) No more VMAs can be found:
 912                          *
 913                          *    find_vma(mm, 16k - 1) will return NULL.
 914                          *    No more things to do, just break.
 915                          *
 916                          * 4) (last_vma_end - 1) is the middle of a vma (VMA'):
 917                          *
 918                          *    find_vma(mm, 16k - 1) will return VMA' whose range
 919                          *    contains last_vma_end.
 920                          *    Iterate VMA' from last_vma_end.
 921                          */
 922                         vma = find_vma(mm, last_vma_end - 1);
 923                         /* Case 3 above */
 924                         if (!vma)
 925                                 break;
 926
 927                         /* Case 1 above */
 928                         if (vma->vm_start >= last_vma_end)
 929                                 continue;
 930
 931                         /* Case 4 above */
 932                         if (vma->vm_end > last_vma_end)
 933                                 smap_gather_stats(vma, &mss, last_vma_end);
 934                 }
 935                 /* Case 2 above */
 936                 vma = vma->vm_next;
 937         }
 938
 939         show_vma_header_prefix(m, priv->mm->mmap->vm_start,
 940                                last_vma_end, 0, 0, 0, 0);
 941         seq_pad(m, ' ');
 942         seq_puts(m, "[rollup]\n");
 943
 944         __show_smap(m, &mss, true);
 945
 946         release_task_mempolicy(priv);
 947         mmap_read_unlock(mm);
 948
 949 out_put_mm:
 950         mmput(mm);
 951 out_put_task:
 952         put_task_struct(priv->task);
 953         priv->task = NULL;
 954
 955         return ret;
 956 }
 957 #undef SEQ_PUT_DEC
 958
 959 static const struct seq_operations proc_pid_smaps_op = {
 960         .start  = m_start,
 961         .next   = m_next,
 962         .stop   = m_stop,
 963         .show   = show_smap
 964 };
 965
 966 static int pid_smaps_open(struct inode *inode, struct file *file)
 967 {
 968         return do_maps_open(inode, file, &proc_pid_smaps_op);
 969 }
 970
 971 static int smaps_rollup_open(struct inode *inode, struct file *file)
 972 {
 973         int ret;
 974         struct proc_maps_private *priv;
 975
 976         priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
 977         if (!priv)
 978                 return -ENOMEM;
 979
 980         ret = single_open(file, show_smaps_rollup, priv);
 981         if (ret)
 982                 goto out_free;
 983
 984         priv->inode = inode;
 985         priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 986         if (IS_ERR(priv->mm)) {
 987                 ret = PTR_ERR(priv->mm);
 988
 989                 single_release(inode, file);
 990                 goto out_free;
 991         }
 992
 993         return 0;
 994
 995 out_free:
 996         kfree(priv);
 997         return ret;
 998 }
 999
1000 static int smaps_rollup_release(struct inode *inode, struct file *file)
1001 {
1002         struct seq_file *seq = file->private_data;
1003         struct proc_maps_private *priv = seq->private;
1004
1005         if (priv->mm)
1006                 mmdrop(priv->mm);
1007
1008         kfree(priv);
1009         return single_release(inode, file);
1010 }
1011
1012 const struct file_operations proc_pid_smaps_operations = {
1013         .open           = pid_smaps_open,
1014         .read           = seq_read,
1015         .llseek         = seq_lseek,
1016         .release        = proc_map_release,
1017 };
1018
1019 const struct file_operations proc_pid_smaps_rollup_operations = {
1020         .open           = smaps_rollup_open,
1021         .read           = seq_read,
1022         .llseek         = seq_lseek,
1023         .release        = smaps_rollup_release,
1024 };
1025
1026 enum clear_refs_types {
1027         CLEAR_REFS_ALL = 1,
1028         CLEAR_REFS_ANON,
1029         CLEAR_REFS_MAPPED,
1030         CLEAR_REFS_SOFT_DIRTY,
1031         CLEAR_REFS_MM_HIWATER_RSS,
1032         CLEAR_REFS_LAST,
1033 };
1034
1035 struct clear_refs_private {
1036         enum clear_refs_types type;
1037 };
1038
1039 #ifdef CONFIG_MEM_SOFT_DIRTY
1040
1041 static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1042 {
1043         struct page *page;
1044
1045         if (!pte_write(pte))
1046                 return false;
1047         if (!is_cow_mapping(vma->vm_flags))
1048                 return false;
1049         if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags)))
1050                 return false;
1051         page = vm_normal_page(vma, addr, pte);
1052         if (!page)
1053                 return false;
1054         return page_maybe_dma_pinned(page);
1055 }
1056
1057 static inline void clear_soft_dirty(struct vm_area_struct *vma,
1058                 unsigned long addr, pte_t *pte)
1059 {
1060         /*
1061          * The soft-dirty tracker uses #PF-s to catch writes
1062          * to pages, so write-protect the pte as well. See the
1063          * Documentation/admin-guide/mm/soft-dirty.rst for full description
1064          * of how soft-dirty works.
1065          */
1066         pte_t ptent = *pte;
1067
1068         if (pte_present(ptent)) {
1069                 pte_t old_pte;
1070
1071                 if (pte_is_pinned(vma, addr, ptent))
1072                         return;
1073                 old_pte = ptep_modify_prot_start(vma, addr, pte);
1074                 ptent = pte_wrprotect(old_pte);
1075                 ptent = pte_clear_soft_dirty(ptent);
1076                 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1077         } else if (is_swap_pte(ptent)) {
1078                 ptent = pte_swp_clear_soft_dirty(ptent);
1079                 set_pte_at(vma->vm_mm, addr, pte, ptent);
1080         }
1081 }
1082 #else
1083 static inline void clear_soft_dirty(struct vm_area_struct *vma,
1084                 unsigned long addr, pte_t *pte)
1085 {
1086 }
1087 #endif
1088
1089 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1090 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1091                 unsigned long addr, pmd_t *pmdp)
1092 {
1093         pmd_t old, pmd = *pmdp;
1094
1095         if (pmd_present(pmd)) {
1096                 /* See comment in change_huge_pmd() */
1097                 old = pmdp_invalidate(vma, addr, pmdp);
1098                 if (pmd_dirty(old))
1099                         pmd = pmd_mkdirty(pmd);
1100                 if (pmd_young(old))
1101                         pmd = pmd_mkyoung(pmd);
1102
1103                 pmd = pmd_wrprotect(pmd);
1104                 pmd = pmd_clear_soft_dirty(pmd);
1105
1106                 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1107         } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1108                 pmd = pmd_swp_clear_soft_dirty(pmd);
1109                 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1110         }
1111 }
1112 #else
1113 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1114                 unsigned long addr, pmd_t *pmdp)
1115 {
1116 }
1117 #endif
1118
1119 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1120                                 unsigned long end, struct mm_walk *walk)
1121 {
1122         struct clear_refs_private *cp = walk->private;
1123         struct vm_area_struct *vma = walk->vma;
1124         pte_t *pte, ptent;
1125         spinlock_t *ptl;
1126         struct page *page;
1127
1128         ptl = pmd_trans_huge_lock(pmd, vma);
1129         if (ptl) {
1130                 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1131                         clear_soft_dirty_pmd(vma, addr, pmd);
1132                         goto out;
1133                 }
1134
1135                 if (!pmd_present(*pmd))
1136                         goto out;
1137
1138                 page = pmd_page(*pmd);
1139
1140                 /* Clear accessed and referenced bits. */
1141                 pmdp_test_and_clear_young(vma, addr, pmd);
1142                 test_and_clear_page_young(page);
1143                 ClearPageReferenced(page);
1144 out:
1145                 spin_unlock(ptl);
1146                 return 0;
1147         }
1148
1149         if (pmd_trans_unstable(pmd))
1150                 return 0;
1151
1152         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1153         for (; addr != end; pte++, addr += PAGE_SIZE) {
1154                 ptent = *pte;
1155
1156                 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1157                         clear_soft_dirty(vma, addr, pte);
1158                         continue;
1159                 }
1160
1161                 if (!pte_present(ptent))
1162                         continue;
1163
1164                 page = vm_normal_page(vma, addr, ptent);
1165                 if (!page)
1166                         continue;
1167
1168                 /* Clear accessed and referenced bits. */
1169                 ptep_test_and_clear_young(vma, addr, pte);
1170                 test_and_clear_page_young(page);
1171                 ClearPageReferenced(page);
1172         }
1173         pte_unmap_unlock(pte - 1, ptl);
1174         cond_resched();
1175         return 0;
1176 }
1177
1178 static int clear_refs_test_walk(unsigned long start, unsigned long end,
1179                                 struct mm_walk *walk)
1180 {
1181         struct clear_refs_private *cp = walk->private;
1182         struct vm_area_struct *vma = walk->vma;
1183
1184         if (vma->vm_flags & VM_PFNMAP)
1185                 return 1;
1186
1187         /*
1188          * Writing 1 to /proc/pid/clear_refs affects all pages.
1189          * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1190          * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1191          * Writing 4 to /proc/pid/clear_refs affects all pages.
1192          */
1193         if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1194                 return 1;
1195         if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1196                 return 1;
1197         return 0;
1198 }
1199
1200 static const struct mm_walk_ops clear_refs_walk_ops = {
1201         .pmd_entry              = clear_refs_pte_range,
1202         .test_walk              = clear_refs_test_walk,
1203 };
1204
1205 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1206                                 size_t count, loff_t *ppos)
1207 {
1208         struct task_struct *task;
1209         char buffer[PROC_NUMBUF];
1210         struct mm_struct *mm;
1211         struct vm_area_struct *vma;
1212         enum clear_refs_types type;
1213         int itype;
1214         int rv;
1215
1216         memset(buffer, 0, sizeof(buffer));
1217         if (count > sizeof(buffer) - 1)
1218                 count = sizeof(buffer) - 1;
1219         if (copy_from_user(buffer, buf, count))
1220                 return -EFAULT;
1221         rv = kstrtoint(strstrip(buffer), 10, &itype);
1222         if (rv < 0)
1223                 return rv;
1224         type = (enum clear_refs_types)itype;
1225         if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1226                 return -EINVAL;
1227
1228         task = get_proc_task(file_inode(file));
1229         if (!task)
1230                 return -ESRCH;
1231         mm = get_task_mm(task);
1232         if (mm) {
1233                 struct mmu_notifier_range range;
1234                 struct clear_refs_private cp = {
1235                         .type = type,
1236                 };
1237
1238                 if (mmap_write_lock_killable(mm)) {
1239                         count = -EINTR;
1240                         goto out_mm;
1241                 }
1242                 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1243                         /*
1244                          * Writing 5 to /proc/pid/clear_refs resets the peak
1245                          * resident set size to this mm's current rss value.
1246                          */
1247                         reset_mm_hiwater_rss(mm);
1248                         goto out_unlock;
1249                 }
1250
1251                 if (type == CLEAR_REFS_SOFT_DIRTY) {
1252                         for (vma = mm->mmap; vma; vma = vma->vm_next) {
1253                                 if (!(vma->vm_flags & VM_SOFTDIRTY))
1254                                         continue;
1255                                 vma->vm_flags &= ~VM_SOFTDIRTY;
1256                                 vma_set_page_prot(vma);
1257                         }
1258
1259                         inc_tlb_flush_pending(mm);
1260                         mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1261                                                 0, NULL, mm, 0, -1UL);
1262                         mmu_notifier_invalidate_range_start(&range);
1263                 }
1264                 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops,
1265                                 &cp);
1266                 if (type == CLEAR_REFS_SOFT_DIRTY) {
1267                         mmu_notifier_invalidate_range_end(&range);
1268                         flush_tlb_mm(mm);
1269                         dec_tlb_flush_pending(mm);
1270                 }
1271 out_unlock:
1272                 mmap_write_unlock(mm);
1273 out_mm:
1274                 mmput(mm);
1275         }
1276         put_task_struct(task);
1277
1278         return count;
1279 }
1280
1281 const struct file_operations proc_clear_refs_operations = {
1282         .write          = clear_refs_write,
1283         .llseek         = noop_llseek,
1284 };
1285
1286 typedef struct {
1287         u64 pme;
1288 } pagemap_entry_t;
1289
1290 struct pagemapread {
1291         int pos, len;           /* units: PM_ENTRY_BYTES, not bytes */
1292         pagemap_entry_t *buffer;
1293         bool show_pfn;
1294 };
1295
1296 #define PAGEMAP_WALK_SIZE       (PMD_SIZE)
1297 #define PAGEMAP_WALK_MASK       (PMD_MASK)
1298
1299 #define PM_ENTRY_BYTES          sizeof(pagemap_entry_t)
1300 #define PM_PFRAME_BITS          55
1301 #define PM_PFRAME_MASK          GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1302 #define PM_SOFT_DIRTY           BIT_ULL(55)
1303 #define PM_MMAP_EXCLUSIVE       BIT_ULL(56)
1304 #define PM_UFFD_WP              BIT_ULL(57)
1305 #define PM_FILE                 BIT_ULL(61)
1306 #define PM_SWAP                 BIT_ULL(62)
1307 #define PM_PRESENT              BIT_ULL(63)
1308
1309 #define PM_END_OF_BUFFER    1
1310
1311 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1312 {
1313         return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1314 }
1315
1316 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1317                           struct pagemapread *pm)
1318 {
1319         pm->buffer[pm->pos++] = *pme;
1320         if (pm->pos >= pm->len)
1321                 return PM_END_OF_BUFFER;
1322         return 0;
1323 }
1324
1325 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1326                             __always_unused int depth, struct mm_walk *walk)
1327 {
1328         struct pagemapread *pm = walk->private;
1329         unsigned long addr = start;
1330         int err = 0;
1331
1332         while (addr < end) {
1333                 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1334                 pagemap_entry_t pme = make_pme(0, 0);
1335                 /* End of address space hole, which we mark as non-present. */
1336                 unsigned long hole_end;
1337
1338                 if (vma)
1339                         hole_end = min(end, vma->vm_start);
1340                 else
1341                         hole_end = end;
1342
1343                 for (; addr < hole_end; addr += PAGE_SIZE) {
1344                         err = add_to_pagemap(addr, &pme, pm);
1345                         if (err)
1346                                 goto out;
1347                 }
1348
1349                 if (!vma)
1350                         break;
1351
1352                 /* Addresses in the VMA. */
1353                 if (vma->vm_flags & VM_SOFTDIRTY)
1354                         pme = make_pme(0, PM_SOFT_DIRTY);
1355                 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1356                         err = add_to_pagemap(addr, &pme, pm);
1357                         if (err)
1358                                 goto out;
1359                 }
1360         }
1361 out:
1362         return err;
1363 }
1364
1365 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1366                 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1367 {
1368         u64 frame = 0, flags = 0;
1369         struct page *page = NULL;
1370
1371         if (pte_present(pte)) {
1372                 if (pm->show_pfn)
1373                         frame = pte_pfn(pte);
1374                 flags |= PM_PRESENT;
1375                 page = vm_normal_page(vma, addr, pte);
1376                 if (pte_soft_dirty(pte))
1377                         flags |= PM_SOFT_DIRTY;
1378                 if (pte_uffd_wp(pte))
1379                         flags |= PM_UFFD_WP;
1380         } else if (is_swap_pte(pte)) {
1381                 swp_entry_t entry;
1382                 if (pte_swp_soft_dirty(pte))
1383                         flags |= PM_SOFT_DIRTY;
1384                 if (pte_swp_uffd_wp(pte))
1385                         flags |= PM_UFFD_WP;
1386                 entry = pte_to_swp_entry(pte);
1387                 if (pm->show_pfn)
1388                         frame = swp_type(entry) |
1389                                 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1390                 flags |= PM_SWAP;
1391                 if (is_pfn_swap_entry(entry))
1392                         page = pfn_swap_entry_to_page(entry);
1393         }
1394
1395         if (page && !PageAnon(page))
1396                 flags |= PM_FILE;
1397         if (page && page_mapcount(page) == 1)
1398                 flags |= PM_MMAP_EXCLUSIVE;
1399         if (vma->vm_flags & VM_SOFTDIRTY)
1400                 flags |= PM_SOFT_DIRTY;
1401
1402         return make_pme(frame, flags);
1403 }
1404
1405 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1406                              struct mm_walk *walk)
1407 {
1408         struct vm_area_struct *vma = walk->vma;
1409         struct pagemapread *pm = walk->private;
1410         spinlock_t *ptl;
1411         pte_t *pte, *orig_pte;
1412         int err = 0;
1413
1414 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1415         ptl = pmd_trans_huge_lock(pmdp, vma);
1416         if (ptl) {
1417                 u64 flags = 0, frame = 0;
1418                 pmd_t pmd = *pmdp;
1419                 struct page *page = NULL;
1420
1421                 if (vma->vm_flags & VM_SOFTDIRTY)
1422                         flags |= PM_SOFT_DIRTY;
1423
1424                 if (pmd_present(pmd)) {
1425                         page = pmd_page(pmd);
1426
1427                         flags |= PM_PRESENT;
1428                         if (pmd_soft_dirty(pmd))
1429                                 flags |= PM_SOFT_DIRTY;
1430                         if (pmd_uffd_wp(pmd))
1431                                 flags |= PM_UFFD_WP;
1432                         if (pm->show_pfn)
1433                                 frame = pmd_pfn(pmd) +
1434                                         ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1435                 }
1436 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1437                 else if (is_swap_pmd(pmd)) {
1438                         swp_entry_t entry = pmd_to_swp_entry(pmd);
1439                         unsigned long offset;
1440
1441                         if (pm->show_pfn) {
1442                                 offset = swp_offset(entry) +
1443                                         ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1444                                 frame = swp_type(entry) |
1445                                         (offset << MAX_SWAPFILES_SHIFT);
1446                         }
1447                         flags |= PM_SWAP;
1448                         if (pmd_swp_soft_dirty(pmd))
1449                                 flags |= PM_SOFT_DIRTY;
1450                         if (pmd_swp_uffd_wp(pmd))
1451                                 flags |= PM_UFFD_WP;
1452                         VM_BUG_ON(!is_pmd_migration_entry(pmd));
1453                         page = pfn_swap_entry_to_page(entry);
1454                 }
1455 #endif
1456
1457                 if (page && page_mapcount(page) == 1)
1458                         flags |= PM_MMAP_EXCLUSIVE;
1459
1460                 for (; addr != end; addr += PAGE_SIZE) {
1461                         pagemap_entry_t pme = make_pme(frame, flags);
1462
1463                         err = add_to_pagemap(addr, &pme, pm);
1464                         if (err)
1465                                 break;
1466                         if (pm->show_pfn) {
1467                                 if (flags & PM_PRESENT)
1468                                         frame++;
1469                                 else if (flags & PM_SWAP)
1470                                         frame += (1 << MAX_SWAPFILES_SHIFT);
1471                         }
1472                 }
1473                 spin_unlock(ptl);
1474                 return err;
1475         }
1476
1477         if (pmd_trans_unstable(pmdp))
1478                 return 0;
1479 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1480
1481         /*
1482          * We can assume that @vma always points to a valid one and @end never
1483          * goes beyond vma->vm_end.
1484          */
1485         orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1486         for (; addr < end; pte++, addr += PAGE_SIZE) {
1487                 pagemap_entry_t pme;
1488
1489                 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1490                 err = add_to_pagemap(addr, &pme, pm);
1491                 if (err)
1492                         break;
1493         }
1494         pte_unmap_unlock(orig_pte, ptl);
1495
1496         cond_resched();
1497
1498         return err;
1499 }
1500
1501 #ifdef CONFIG_HUGETLB_PAGE
1502 /* This function walks within one hugetlb entry in the single call */
1503 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1504                                  unsigned long addr, unsigned long end,
1505                                  struct mm_walk *walk)
1506 {
1507         struct pagemapread *pm = walk->private;
1508         struct vm_area_struct *vma = walk->vma;
1509         u64 flags = 0, frame = 0;
1510         int err = 0;
1511         pte_t pte;
1512
1513         if (vma->vm_flags & VM_SOFTDIRTY)
1514                 flags |= PM_SOFT_DIRTY;
1515
1516         pte = huge_ptep_get(ptep);
1517         if (pte_present(pte)) {
1518                 struct page *page = pte_page(pte);
1519
1520                 if (!PageAnon(page))
1521                         flags |= PM_FILE;
1522
1523                 if (page_mapcount(page) == 1)
1524                         flags |= PM_MMAP_EXCLUSIVE;
1525
1526                 flags |= PM_PRESENT;
1527                 if (pm->show_pfn)
1528                         frame = pte_pfn(pte) +
1529                                 ((addr & ~hmask) >> PAGE_SHIFT);
1530         }
1531
1532         for (; addr != end; addr += PAGE_SIZE) {
1533                 pagemap_entry_t pme = make_pme(frame, flags);
1534
1535                 err = add_to_pagemap(addr, &pme, pm);
1536                 if (err)
1537                         return err;
1538                 if (pm->show_pfn && (flags & PM_PRESENT))
1539                         frame++;
1540         }
1541
1542         cond_resched();
1543
1544         return err;
1545 }
1546 #else
1547 #define pagemap_hugetlb_range   NULL
1548 #endif /* HUGETLB_PAGE */
1549
1550 static const struct mm_walk_ops pagemap_ops = {
1551         .pmd_entry      = pagemap_pmd_range,
1552         .pte_hole       = pagemap_pte_hole,
1553         .hugetlb_entry  = pagemap_hugetlb_range,
1554 };
1555
1556 /*
1557  * /proc/pid/pagemap - an array mapping virtual pages to pfns
1558  *
1559  * For each page in the address space, this file contains one 64-bit entry
1560  * consisting of the following:
1561  *
1562  * Bits 0-54  page frame number (PFN) if present
1563  * Bits 0-4   swap type if swapped
1564  * Bits 5-54  swap offset if swapped
1565  * Bit  55    pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1566  * Bit  56    page exclusively mapped
1567  * Bits 57-60 zero
1568  * Bit  61    page is file-page or shared-anon
1569  * Bit  62    page swapped
1570  * Bit  63    page present
1571  *
1572  * If the page is not present but in swap, then the PFN contains an
1573  * encoding of the swap file number and the page's offset into the
1574  * swap. Unmapped pages return a null PFN. This allows determining
1575  * precisely which pages are mapped (or in swap) and comparing mapped
1576  * pages between processes.
1577  *
1578  * Efficient users of this interface will use /proc/pid/maps to
1579  * determine which areas of memory are actually mapped and llseek to
1580  * skip over unmapped regions.
1581  */
1582 static ssize_t pagemap_read(struct file *file, char __user *buf,
1583                             size_t count, loff_t *ppos)
1584 {
1585         struct mm_struct *mm = file->private_data;
1586         struct pagemapread pm;
1587         unsigned long src;
1588         unsigned long svpfn;
1589         unsigned long start_vaddr;
1590         unsigned long end_vaddr;
1591         int ret = 0, copied = 0;
1592
1593         if (!mm || !mmget_not_zero(mm))
1594                 goto out;
1595
1596         ret = -EINVAL;
1597         /* file position must be aligned */
1598         if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1599                 goto out_mm;
1600
1601         ret = 0;
1602         if (!count)
1603                 goto out_mm;
1604
1605         /* do not disclose physical addresses: attack vector */
1606         pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1607
1608         pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1609         pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1610         ret = -ENOMEM;
1611         if (!pm.buffer)
1612                 goto out_mm;
1613
1614         src = *ppos;
1615         svpfn = src / PM_ENTRY_BYTES;
1616         end_vaddr = mm->task_size;
1617
1618         /* watch out for wraparound */
1619         start_vaddr = end_vaddr;
1620         if (svpfn <= (ULONG_MAX >> PAGE_SHIFT))
1621                 start_vaddr = untagged_addr(svpfn << PAGE_SHIFT);
1622
1623         /* Ensure the address is inside the task */
1624         if (start_vaddr > mm->task_size)
1625                 start_vaddr = end_vaddr;
1626
1627         /*
1628          * The odds are that this will stop walking way
1629          * before end_vaddr, because the length of the
1630          * user buffer is tracked in "pm", and the walk
1631          * will stop when we hit the end of the buffer.
1632          */
1633         ret = 0;
1634         while (count && (start_vaddr < end_vaddr)) {
1635                 int len;
1636                 unsigned long end;
1637
1638                 pm.pos = 0;
1639                 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1640                 /* overflow ? */
1641                 if (end < start_vaddr || end > end_vaddr)
1642                         end = end_vaddr;
1643                 ret = mmap_read_lock_killable(mm);
1644                 if (ret)
1645                         goto out_free;
1646                 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1647                 mmap_read_unlock(mm);
1648                 start_vaddr = end;
1649
1650                 len = min(count, PM_ENTRY_BYTES * pm.pos);
1651                 if (copy_to_user(buf, pm.buffer, len)) {
1652                         ret = -EFAULT;
1653                         goto out_free;
1654                 }
1655                 copied += len;
1656                 buf += len;
1657                 count -= len;
1658         }
1659         *ppos += copied;
1660         if (!ret || ret == PM_END_OF_BUFFER)
1661                 ret = copied;
1662
1663 out_free:
1664         kfree(pm.buffer);
1665 out_mm:
1666         mmput(mm);
1667 out:
1668         return ret;
1669 }
1670
1671 static int pagemap_open(struct inode *inode, struct file *file)
1672 {
1673         struct mm_struct *mm;
1674
1675         mm = proc_mem_open(inode, PTRACE_MODE_READ);
1676         if (IS_ERR(mm))
1677                 return PTR_ERR(mm);
1678         file->private_data = mm;
1679         return 0;
1680 }
1681
1682 static int pagemap_release(struct inode *inode, struct file *file)
1683 {
1684         struct mm_struct *mm = file->private_data;
1685
1686         if (mm)
1687                 mmdrop(mm);
1688         return 0;
1689 }
1690
1691 const struct file_operations proc_pagemap_operations = {
1692         .llseek         = mem_lseek, /* borrow this */
1693         .read           = pagemap_read,
1694         .open           = pagemap_open,
1695         .release        = pagemap_release,
1696 };
1697 #endif /* CONFIG_PROC_PAGE_MONITOR */
1698
1699 #ifdef CONFIG_NUMA
1700
1701 struct numa_maps {
1702         unsigned long pages;
1703         unsigned long anon;
1704         unsigned long active;
1705         unsigned long writeback;
1706         unsigned long mapcount_max;
1707         unsigned long dirty;
1708         unsigned long swapcache;
1709         unsigned long node[MAX_NUMNODES];
1710 };
1711
1712 struct numa_maps_private {
1713         struct proc_maps_private proc_maps;
1714         struct numa_maps md;
1715 };
1716
1717 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1718                         unsigned long nr_pages)
1719 {
1720         int count = page_mapcount(page);
1721
1722         md->pages += nr_pages;
1723         if (pte_dirty || PageDirty(page))
1724                 md->dirty += nr_pages;
1725
1726         if (PageSwapCache(page))
1727                 md->swapcache += nr_pages;
1728
1729         if (PageActive(page) || PageUnevictable(page))
1730                 md->active += nr_pages;
1731
1732         if (PageWriteback(page))
1733                 md->writeback += nr_pages;
1734
1735         if (PageAnon(page))
1736                 md->anon += nr_pages;
1737
1738         if (count > md->mapcount_max)
1739                 md->mapcount_max = count;
1740
1741         md->node[page_to_nid(page)] += nr_pages;
1742 }
1743
1744 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1745                 unsigned long addr)
1746 {
1747         struct page *page;
1748         int nid;
1749
1750         if (!pte_present(pte))
1751                 return NULL;
1752
1753         page = vm_normal_page(vma, addr, pte);
1754         if (!page)
1755                 return NULL;
1756
1757         if (PageReserved(page))
1758                 return NULL;
1759
1760         nid = page_to_nid(page);
1761         if (!node_isset(nid, node_states[N_MEMORY]))
1762                 return NULL;
1763
1764         return page;
1765 }
1766
1767 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1768 static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1769                                               struct vm_area_struct *vma,
1770                                               unsigned long addr)
1771 {
1772         struct page *page;
1773         int nid;
1774
1775         if (!pmd_present(pmd))
1776                 return NULL;
1777
1778         page = vm_normal_page_pmd(vma, addr, pmd);
1779         if (!page)
1780                 return NULL;
1781
1782         if (PageReserved(page))
1783                 return NULL;
1784
1785         nid = page_to_nid(page);
1786         if (!node_isset(nid, node_states[N_MEMORY]))
1787                 return NULL;
1788
1789         return page;
1790 }
1791 #endif
1792
1793 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1794                 unsigned long end, struct mm_walk *walk)
1795 {
1796         struct numa_maps *md = walk->private;
1797         struct vm_area_struct *vma = walk->vma;
1798         spinlock_t *ptl;
1799         pte_t *orig_pte;
1800         pte_t *pte;
1801
1802 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1803         ptl = pmd_trans_huge_lock(pmd, vma);
1804         if (ptl) {
1805                 struct page *page;
1806
1807                 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1808                 if (page)
1809                         gather_stats(page, md, pmd_dirty(*pmd),
1810                                      HPAGE_PMD_SIZE/PAGE_SIZE);
1811                 spin_unlock(ptl);
1812                 return 0;
1813         }
1814
1815         if (pmd_trans_unstable(pmd))
1816                 return 0;
1817 #endif
1818         orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1819         do {
1820                 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1821                 if (!page)
1822                         continue;
1823                 gather_stats(page, md, pte_dirty(*pte), 1);
1824
1825         } while (pte++, addr += PAGE_SIZE, addr != end);
1826         pte_unmap_unlock(orig_pte, ptl);
1827         cond_resched();
1828         return 0;
1829 }
1830 #ifdef CONFIG_HUGETLB_PAGE
1831 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1832                 unsigned long addr, unsigned long end, struct mm_walk *walk)
1833 {
1834         pte_t huge_pte = huge_ptep_get(pte);
1835         struct numa_maps *md;
1836         struct page *page;
1837
1838         if (!pte_present(huge_pte))
1839                 return 0;
1840
1841         page = pte_page(huge_pte);
1842         if (!page)
1843                 return 0;
1844
1845         md = walk->private;
1846         gather_stats(page, md, pte_dirty(huge_pte), 1);
1847         return 0;
1848 }
1849
1850 #else
1851 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1852                 unsigned long addr, unsigned long end, struct mm_walk *walk)
1853 {
1854         return 0;
1855 }
1856 #endif
1857
1858 static const struct mm_walk_ops show_numa_ops = {
1859         .hugetlb_entry = gather_hugetlb_stats,
1860         .pmd_entry = gather_pte_stats,
1861 };
1862
1863 /*
1864  * Display pages allocated per node and memory policy via /proc.
1865  */
1866 static int show_numa_map(struct seq_file *m, void *v)
1867 {
1868         struct numa_maps_private *numa_priv = m->private;
1869         struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1870         struct vm_area_struct *vma = v;
1871         struct numa_maps *md = &numa_priv->md;
1872         struct file *file = vma->vm_file;
1873         struct mm_struct *mm = vma->vm_mm;
1874         struct mempolicy *pol;
1875         char buffer[64];
1876         int nid;
1877
1878         if (!mm)
1879                 return 0;
1880
1881         /* Ensure we start with an empty set of numa_maps statistics. */
1882         memset(md, 0, sizeof(*md));
1883
1884         pol = __get_vma_policy(vma, vma->vm_start);
1885         if (pol) {
1886                 mpol_to_str(buffer, sizeof(buffer), pol);
1887                 mpol_cond_put(pol);
1888         } else {
1889                 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1890         }
1891
1892         seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1893
1894         if (file) {
1895                 seq_puts(m, " file=");
1896                 seq_file_path(m, file, "\n\t= ");
1897         } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1898                 seq_puts(m, " heap");
1899         } else if (is_stack(vma)) {
1900                 seq_puts(m, " stack");
1901         }
1902
1903         if (is_vm_hugetlb_page(vma))
1904                 seq_puts(m, " huge");
1905
1906         /* mmap_lock is held by m_start */
1907         walk_page_vma(vma, &show_numa_ops, md);
1908
1909         if (!md->pages)
1910                 goto out;
1911
1912         if (md->anon)
1913                 seq_printf(m, " anon=%lu", md->anon);
1914
1915         if (md->dirty)
1916                 seq_printf(m, " dirty=%lu", md->dirty);
1917
1918         if (md->pages != md->anon && md->pages != md->dirty)
1919                 seq_printf(m, " mapped=%lu", md->pages);
1920
1921         if (md->mapcount_max > 1)
1922                 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1923
1924         if (md->swapcache)
1925                 seq_printf(m, " swapcache=%lu", md->swapcache);
1926
1927         if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1928                 seq_printf(m, " active=%lu", md->active);
1929
1930         if (md->writeback)
1931                 seq_printf(m, " writeback=%lu", md->writeback);
1932
1933         for_each_node_state(nid, N_MEMORY)
1934                 if (md->node[nid])
1935                         seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1936
1937         seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1938 out:
1939         seq_putc(m, '\n');
1940         return 0;
1941 }
1942
1943 static const struct seq_operations proc_pid_numa_maps_op = {
1944         .start  = m_start,
1945         .next   = m_next,
1946         .stop   = m_stop,
1947         .show   = show_numa_map,
1948 };
1949
1950 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1951 {
1952         return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
1953                                 sizeof(struct numa_maps_private));
1954 }
1955
1956 const struct file_operations proc_pid_numa_maps_operations = {
1957         .open           = pid_numa_maps_open,
1958         .read           = seq_read,
1959         .llseek         = seq_lseek,
1960         .release        = proc_map_release,
1961 };
1962
1963 #endif /* CONFIG_NUMA */