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/mm_inline.h>
   5 #include <linux/hugetlb.h>
   6 #include <linux/huge_mm.h>
   7 #include <linux/mount.h>
   8 #include <linux/seq_file.h>
   9 #include <linux/highmem.h>
  10 #include <linux/ptrace.h>
  11 #include <linux/slab.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/mempolicy.h>
  14 #include <linux/rmap.h>
  15 #include <linux/swap.h>
  16 #include <linux/sched/mm.h>
  17 #include <linux/swapops.h>
  18 #include <linux/mmu_notifier.h>
  19 #include <linux/page_idle.h>
  20 #include <linux/shmem_fs.h>
  21 #include <linux/uaccess.h>
  22 #include <linux/pkeys.h>
  23
  24 #include <asm/elf.h>
  25 #include <asm/tlb.h>
  26 #include <asm/tlbflush.h>
  27 #include "internal.h"
  28
  29 #define SEQ_PUT_DEC(str, val) \
  30                 seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
  31 void task_mem(struct seq_file *m, struct mm_struct *mm)
  32 {
  33         unsigned long text, lib, swap, anon, file, shmem;
  34         unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
  35
  36         anon = get_mm_counter(mm, MM_ANONPAGES);
  37         file = get_mm_counter(mm, MM_FILEPAGES);
  38         shmem = get_mm_counter(mm, MM_SHMEMPAGES);
  39
  40         /*
  41          * Note: to minimize their overhead, mm maintains hiwater_vm and
  42          * hiwater_rss only when about to *lower* total_vm or rss.  Any
  43          * collector of these hiwater stats must therefore get total_vm
  44          * and rss too, which will usually be the higher.  Barriers? not
  45          * worth the effort, such snapshots can always be inconsistent.
  46          */
  47         hiwater_vm = total_vm = mm->total_vm;
  48         if (hiwater_vm < mm->hiwater_vm)
  49                 hiwater_vm = mm->hiwater_vm;
  50         hiwater_rss = total_rss = anon + file + shmem;
  51         if (hiwater_rss < mm->hiwater_rss)
  52                 hiwater_rss = mm->hiwater_rss;
  53
  54         /* split executable areas between text and lib */
  55         text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
  56         text = min(text, mm->exec_vm << PAGE_SHIFT);
  57         lib = (mm->exec_vm << PAGE_SHIFT) - text;
  58
  59         swap = get_mm_counter(mm, MM_SWAPENTS);
  60         SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
  61         SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
  62         SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
  63         SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm));
  64         SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
  65         SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
  66         SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
  67         SEQ_PUT_DEC(" kB\nRssFile:\t", file);
  68         SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
  69         SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
  70         SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
  71         seq_put_decimal_ull_width(m,
  72                     " kB\nVmExe:\t", text >> 10, 8);
  73         seq_put_decimal_ull_width(m,
  74                     " kB\nVmLib:\t", lib >> 10, 8);
  75         seq_put_decimal_ull_width(m,
  76                     " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
  77         SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
  78         seq_puts(m, " kB\n");
  79         hugetlb_report_usage(m, mm);
  80 }
  81 #undef SEQ_PUT_DEC
  82
  83 unsigned long task_vsize(struct mm_struct *mm)
  84 {
  85         return PAGE_SIZE * mm->total_vm;
  86 }
  87
  88 unsigned long task_statm(struct mm_struct *mm,
  89                          unsigned long *shared, unsigned long *text,
  90                          unsigned long *data, unsigned long *resident)
  91 {
  92         *shared = get_mm_counter(mm, MM_FILEPAGES) +
  93                         get_mm_counter(mm, MM_SHMEMPAGES);
  94         *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
  95                                                                 >> PAGE_SHIFT;
  96         *data = mm->data_vm + mm->stack_vm;
  97         *resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
  98         return mm->total_vm;
  99 }
 100
 101 #ifdef CONFIG_NUMA
 102 /*
 103  * Save get_task_policy() for show_numa_map().
 104  */
 105 static void hold_task_mempolicy(struct proc_maps_private *priv)
 106 {
 107         struct task_struct *task = priv->task;
 108
 109         task_lock(task);
 110         priv->task_mempolicy = get_task_policy(task);
 111         mpol_get(priv->task_mempolicy);
 112         task_unlock(task);
 113 }
 114 static void release_task_mempolicy(struct proc_maps_private *priv)
 115 {
 116         mpol_put(priv->task_mempolicy);
 117 }
 118 #else
 119 static void hold_task_mempolicy(struct proc_maps_private *priv)
 120 {
 121 }
 122 static void release_task_mempolicy(struct proc_maps_private *priv)
 123 {
 124 }
 125 #endif
 126
 127 static void *m_start(struct seq_file *m, loff_t *ppos)
 128 {
 129         struct proc_maps_private *priv = m->private;
 130         unsigned long last_addr = *ppos;
 131         struct mm_struct *mm;
 132         struct vm_area_struct *vma;
 133
 134         /* See m_next(). Zero at the start or after lseek. */
 135         if (last_addr == -1UL)
 136                 return NULL;
 137
 138         priv->task = get_proc_task(priv->inode);
 139         if (!priv->task)
 140                 return ERR_PTR(-ESRCH);
 141
 142         mm = priv->mm;
 143         if (!mm || !mmget_not_zero(mm)) {
 144                 put_task_struct(priv->task);
 145                 priv->task = NULL;
 146                 return NULL;
 147         }
 148
 149         if (mmap_read_lock_killable(mm)) {
 150                 mmput(mm);
 151                 put_task_struct(priv->task);
 152                 priv->task = NULL;
 153                 return ERR_PTR(-EINTR);
 154         }
 155
 156         hold_task_mempolicy(priv);
 157         priv->tail_vma = get_gate_vma(mm);
 158
 159         vma = find_vma(mm, last_addr);
 160         if (vma)
 161                 return vma;
 162
 163         return priv->tail_vma;
 164 }
 165
 166 static void *m_next(struct seq_file *m, void *v, loff_t *ppos)
 167 {
 168         struct proc_maps_private *priv = m->private;
 169         struct vm_area_struct *next, *vma = v;
 170
 171         if (vma == priv->tail_vma)
 172                 next = NULL;
 173         else if (vma->vm_next)
 174                 next = vma->vm_next;
 175         else
 176                 next = priv->tail_vma;
 177
 178         *ppos = next ? next->vm_start : -1UL;
 179
 180         return next;
 181 }
 182
 183 static void m_stop(struct seq_file *m, void *v)
 184 {
 185         struct proc_maps_private *priv = m->private;
 186         struct mm_struct *mm = priv->mm;
 187
 188         if (!priv->task)
 189                 return;
 190
 191         release_task_mempolicy(priv);
 192         mmap_read_unlock(mm);
 193         mmput(mm);
 194         put_task_struct(priv->task);
 195         priv->task = NULL;
 196 }
 197
 198 static int proc_maps_open(struct inode *inode, struct file *file,
 199                         const struct seq_operations *ops, int psize)
 200 {
 201         struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
 202
 203         if (!priv)
 204                 return -ENOMEM;
 205
 206         priv->inode = inode;
 207         priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 208         if (IS_ERR(priv->mm)) {
 209                 int err = PTR_ERR(priv->mm);
 210
 211                 seq_release_private(inode, file);
 212                 return err;
 213         }
 214
 215         return 0;
 216 }
 217
 218 static int proc_map_release(struct inode *inode, struct file *file)
 219 {
 220         struct seq_file *seq = file->private_data;
 221         struct proc_maps_private *priv = seq->private;
 222
 223         if (priv->mm)
 224                 mmdrop(priv->mm);
 225
 226         return seq_release_private(inode, file);
 227 }
 228
 229 static int do_maps_open(struct inode *inode, struct file *file,
 230                         const struct seq_operations *ops)
 231 {
 232         return proc_maps_open(inode, file, ops,
 233                                 sizeof(struct proc_maps_private));
 234 }
 235
 236 /*
 237  * Indicate if the VMA is a stack for the given task; for
 238  * /proc/PID/maps that is the stack of the main task.
 239  */
 240 static int is_stack(struct vm_area_struct *vma)
 241 {
 242         /*
 243          * We make no effort to guess what a given thread considers to be
 244          * its "stack".  It's not even well-defined for programs written
 245          * languages like Go.
 246          */
 247         return vma->vm_start <= vma->vm_mm->start_stack &&
 248                 vma->vm_end >= vma->vm_mm->start_stack;
 249 }
 250
 251 static void show_vma_header_prefix(struct seq_file *m,
 252                                    unsigned long start, unsigned long end,
 253                                    vm_flags_t flags, unsigned long long pgoff,
 254                                    dev_t dev, unsigned long ino)
 255 {
 256         seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
 257         seq_put_hex_ll(m, NULL, start, 8);
 258         seq_put_hex_ll(m, "-", end, 8);
 259         seq_putc(m, ' ');
 260         seq_putc(m, flags & VM_READ ? 'r' : '-');
 261         seq_putc(m, flags & VM_WRITE ? 'w' : '-');
 262         seq_putc(m, flags & VM_EXEC ? 'x' : '-');
 263         seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
 264         seq_put_hex_ll(m, " ", pgoff, 8);
 265         seq_put_hex_ll(m, " ", MAJOR(dev), 2);
 266         seq_put_hex_ll(m, ":", MINOR(dev), 2);
 267         seq_put_decimal_ull(m, " ", ino);
 268         seq_putc(m, ' ');
 269 }
 270
 271 static void
 272 show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
 273 {
 274         struct mm_struct *mm = vma->vm_mm;
 275         struct file *file = vma->vm_file;
 276         vm_flags_t flags = vma->vm_flags;
 277         unsigned long ino = 0;
 278         unsigned long long pgoff = 0;
 279         unsigned long start, end;
 280         dev_t dev = 0;
 281         const char *name = NULL;
 282
 283         if (file) {
 284                 struct inode *inode = file_inode(vma->vm_file);
 285                 dev = inode->i_sb->s_dev;
 286                 ino = inode->i_ino;
 287                 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
 288         }
 289
 290         start = vma->vm_start;
 291         end = vma->vm_end;
 292         show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
 293
 294         /*
 295          * Print the dentry name for named mappings, and a
 296          * special [heap] marker for the heap:
 297          */
 298         if (file) {
 299                 seq_pad(m, ' ');
 300                 seq_file_path(m, file, "\n");
 301                 goto done;
 302         }
 303
 304         if (vma->vm_ops && vma->vm_ops->name) {
 305                 name = vma->vm_ops->name(vma);
 306                 if (name)
 307                         goto done;
 308         }
 309
 310         name = arch_vma_name(vma);
 311         if (!name) {
 312                 struct anon_vma_name *anon_name;
 313
 314                 if (!mm) {
 315                         name = "[vdso]";
 316                         goto done;
 317                 }
 318
 319                 if (vma->vm_start <= mm->brk &&
 320                     vma->vm_end >= mm->start_brk) {
 321                         name = "[heap]";
 322                         goto done;
 323                 }
 324
 325                 if (is_stack(vma)) {
 326                         name = "[stack]";
 327                         goto done;
 328                 }
 329
 330                 anon_name = anon_vma_name(vma);
 331                 if (anon_name) {
 332                         seq_pad(m, ' ');
 333                         seq_printf(m, "[anon:%s]", anon_name->name);
 334                 }
 335         }
 336
 337 done:
 338         if (name) {
 339                 seq_pad(m, ' ');
 340                 seq_puts(m, name);
 341         }
 342         seq_putc(m, '\n');
 343 }
 344
 345 static int show_map(struct seq_file *m, void *v)
 346 {
 347         show_map_vma(m, v);
 348         return 0;
 349 }
 350
 351 static const struct seq_operations proc_pid_maps_op = {
 352         .start  = m_start,
 353         .next   = m_next,
 354         .stop   = m_stop,
 355         .show   = show_map
 356 };
 357
 358 static int pid_maps_open(struct inode *inode, struct file *file)
 359 {
 360         return do_maps_open(inode, file, &proc_pid_maps_op);
 361 }
 362
 363 const struct file_operations proc_pid_maps_operations = {
 364         .open           = pid_maps_open,
 365         .read           = seq_read,
 366         .llseek         = seq_lseek,
 367         .release        = proc_map_release,
 368 };
 369
 370 /*
 371  * Proportional Set Size(PSS): my share of RSS.
 372  *
 373  * PSS of a process is the count of pages it has in memory, where each
 374  * page is divided by the number of processes sharing it.  So if a
 375  * process has 1000 pages all to itself, and 1000 shared with one other
 376  * process, its PSS will be 1500.
 377  *
 378  * To keep (accumulated) division errors low, we adopt a 64bit
 379  * fixed-point pss counter to minimize division errors. So (pss >>
 380  * PSS_SHIFT) would be the real byte count.
 381  *
 382  * A shift of 12 before division means (assuming 4K page size):
 383  *      - 1M 3-user-pages add up to 8KB errors;
 384  *      - supports mapcount up to 2^24, or 16M;
 385  *      - supports PSS up to 2^52 bytes, or 4PB.
 386  */
 387 #define PSS_SHIFT 12
 388
 389 #ifdef CONFIG_PROC_PAGE_MONITOR
 390 struct mem_size_stats {
 391         unsigned long resident;
 392         unsigned long shared_clean;
 393         unsigned long shared_dirty;
 394         unsigned long private_clean;
 395         unsigned long private_dirty;
 396         unsigned long referenced;
 397         unsigned long anonymous;
 398         unsigned long lazyfree;
 399         unsigned long anonymous_thp;
 400         unsigned long shmem_thp;
 401         unsigned long file_thp;
 402         unsigned long swap;
 403         unsigned long shared_hugetlb;
 404         unsigned long private_hugetlb;
 405         u64 pss;
 406         u64 pss_anon;
 407         u64 pss_file;
 408         u64 pss_shmem;
 409         u64 pss_dirty;
 410         u64 pss_locked;
 411         u64 swap_pss;
 412 };
 413
 414 static void smaps_page_accumulate(struct mem_size_stats *mss,
 415                 struct page *page, unsigned long size, unsigned long pss,
 416                 bool dirty, bool locked, bool private)
 417 {
 418         mss->pss += pss;
 419
 420         if (PageAnon(page))
 421                 mss->pss_anon += pss;
 422         else if (PageSwapBacked(page))
 423                 mss->pss_shmem += pss;
 424         else
 425                 mss->pss_file += pss;
 426
 427         if (locked)
 428                 mss->pss_locked += pss;
 429
 430         if (dirty || PageDirty(page)) {
 431                 mss->pss_dirty += pss;
 432                 if (private)
 433                         mss->private_dirty += size;
 434                 else
 435                         mss->shared_dirty += size;
 436         } else {
 437                 if (private)
 438                         mss->private_clean += size;
 439                 else
 440                         mss->shared_clean += size;
 441         }
 442 }
 443
 444 static void smaps_account(struct mem_size_stats *mss, struct page *page,
 445                 bool compound, bool young, bool dirty, bool locked,
 446                 bool migration)
 447 {
 448         int i, nr = compound ? compound_nr(page) : 1;
 449         unsigned long size = nr * PAGE_SIZE;
 450
 451         /*
 452          * First accumulate quantities that depend only on |size| and the type
 453          * of the compound page.
 454          */
 455         if (PageAnon(page)) {
 456                 mss->anonymous += size;
 457                 if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
 458                         mss->lazyfree += size;
 459         }
 460
 461         mss->resident += size;
 462         /* Accumulate the size in pages that have been accessed. */
 463         if (young || page_is_young(page) || PageReferenced(page))
 464                 mss->referenced += size;
 465
 466         /*
 467          * Then accumulate quantities that may depend on sharing, or that may
 468          * differ page-by-page.
 469          *
 470          * page_count(page) == 1 guarantees the page is mapped exactly once.
 471          * If any subpage of the compound page mapped with PTE it would elevate
 472          * page_count().
 473          *
 474          * The page_mapcount() is called to get a snapshot of the mapcount.
 475          * Without holding the page lock this snapshot can be slightly wrong as
 476          * we cannot always read the mapcount atomically.  It is not safe to
 477          * call page_mapcount() even with PTL held if the page is not mapped,
 478          * especially for migration entries.  Treat regular migration entries
 479          * as mapcount == 1.
 480          */
 481         if ((page_count(page) == 1) || migration) {
 482                 smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
 483                         locked, true);
 484                 return;
 485         }
 486         for (i = 0; i < nr; i++, page++) {
 487                 int mapcount = page_mapcount(page);
 488                 unsigned long pss = PAGE_SIZE << PSS_SHIFT;
 489                 if (mapcount >= 2)
 490                         pss /= mapcount;
 491                 smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
 492                                       mapcount < 2);
 493         }
 494 }
 495
 496 #ifdef CONFIG_SHMEM
 497 static int smaps_pte_hole(unsigned long addr, unsigned long end,
 498                           __always_unused int depth, struct mm_walk *walk)
 499 {
 500         struct mem_size_stats *mss = walk->private;
 501         struct vm_area_struct *vma = walk->vma;
 502
 503         mss->swap += shmem_partial_swap_usage(walk->vma->vm_file->f_mapping,
 504                                               linear_page_index(vma, addr),
 505                                               linear_page_index(vma, end));
 506
 507         return 0;
 508 }
 509 #else
 510 #define smaps_pte_hole          NULL
 511 #endif /* CONFIG_SHMEM */
 512
 513 static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk)
 514 {
 515 #ifdef CONFIG_SHMEM
 516         if (walk->ops->pte_hole) {
 517                 /* depth is not used */
 518                 smaps_pte_hole(addr, addr + PAGE_SIZE, 0, walk);
 519         }
 520 #endif
 521 }
 522
 523 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 524                 struct mm_walk *walk)
 525 {
 526         struct mem_size_stats *mss = walk->private;
 527         struct vm_area_struct *vma = walk->vma;
 528         bool locked = !!(vma->vm_flags & VM_LOCKED);
 529         struct page *page = NULL;
 530         bool migration = false;
 531
 532         if (pte_present(*pte)) {
 533                 page = vm_normal_page(vma, addr, *pte);
 534         } else if (is_swap_pte(*pte)) {
 535                 swp_entry_t swpent = pte_to_swp_entry(*pte);
 536
 537                 if (!non_swap_entry(swpent)) {
 538                         int mapcount;
 539
 540                         mss->swap += PAGE_SIZE;
 541                         mapcount = swp_swapcount(swpent);
 542                         if (mapcount >= 2) {
 543                                 u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
 544
 545                                 do_div(pss_delta, mapcount);
 546                                 mss->swap_pss += pss_delta;
 547                         } else {
 548                                 mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 549                         }
 550                 } else if (is_pfn_swap_entry(swpent)) {
 551                         if (is_migration_entry(swpent))
 552                                 migration = true;
 553                         page = pfn_swap_entry_to_page(swpent);
 554                 }
 555         } else {
 556                 smaps_pte_hole_lookup(addr, walk);
 557                 return;
 558         }
 559
 560         if (!page)
 561                 return;
 562
 563         smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte),
 564                       locked, migration);
 565 }
 566
 567 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 568 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 569                 struct mm_walk *walk)
 570 {
 571         struct mem_size_stats *mss = walk->private;
 572         struct vm_area_struct *vma = walk->vma;
 573         bool locked = !!(vma->vm_flags & VM_LOCKED);
 574         struct page *page = NULL;
 575         bool migration = false;
 576
 577         if (pmd_present(*pmd)) {
 578                 /* FOLL_DUMP will return -EFAULT on huge zero page */
 579                 page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
 580         } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
 581                 swp_entry_t entry = pmd_to_swp_entry(*pmd);
 582
 583                 if (is_migration_entry(entry)) {
 584                         migration = true;
 585                         page = pfn_swap_entry_to_page(entry);
 586                 }
 587         }
 588         if (IS_ERR_OR_NULL(page))
 589                 return;
 590         if (PageAnon(page))
 591                 mss->anonymous_thp += HPAGE_PMD_SIZE;
 592         else if (PageSwapBacked(page))
 593                 mss->shmem_thp += HPAGE_PMD_SIZE;
 594         else if (is_zone_device_page(page))
 595                 /* pass */;
 596         else
 597                 mss->file_thp += HPAGE_PMD_SIZE;
 598
 599         smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd),
 600                       locked, migration);
 601 }
 602 #else
 603 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 604                 struct mm_walk *walk)
 605 {
 606 }
 607 #endif
 608
 609 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 610                            struct mm_walk *walk)
 611 {
 612         struct vm_area_struct *vma = walk->vma;
 613         pte_t *pte;
 614         spinlock_t *ptl;
 615
 616         ptl = pmd_trans_huge_lock(pmd, vma);
 617         if (ptl) {
 618                 smaps_pmd_entry(pmd, addr, walk);
 619                 spin_unlock(ptl);
 620                 goto out;
 621         }
 622
 623         if (pmd_trans_unstable(pmd))
 624                 goto out;
 625         /*
 626          * The mmap_lock held all the way back in m_start() is what
 627          * keeps khugepaged out of here and from collapsing things
 628          * in here.
 629          */
 630         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 631         for (; addr != end; pte++, addr += PAGE_SIZE)
 632                 smaps_pte_entry(pte, addr, walk);
 633         pte_unmap_unlock(pte - 1, ptl);
 634 out:
 635         cond_resched();
 636         return 0;
 637 }
 638
 639 static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 640 {
 641         /*
 642          * Don't forget to update Documentation/ on changes.
 643          */
 644         static const char mnemonics[BITS_PER_LONG][2] = {
 645                 /*
 646                  * In case if we meet a flag we don't know about.
 647                  */
 648                 [0 ... (BITS_PER_LONG-1)] = "??",
 649
 650                 [ilog2(VM_READ)]        = "rd",
 651                 [ilog2(VM_WRITE)]       = "wr",
 652                 [ilog2(VM_EXEC)]        = "ex",
 653                 [ilog2(VM_SHARED)]      = "sh",
 654                 [ilog2(VM_MAYREAD)]     = "mr",
 655                 [ilog2(VM_MAYWRITE)]    = "mw",
 656                 [ilog2(VM_MAYEXEC)]     = "me",
 657                 [ilog2(VM_MAYSHARE)]    = "ms",
 658                 [ilog2(VM_GROWSDOWN)]   = "gd",
 659                 [ilog2(VM_PFNMAP)]      = "pf",
 660                 [ilog2(VM_LOCKED)]      = "lo",
 661                 [ilog2(VM_IO)]          = "io",
 662                 [ilog2(VM_SEQ_READ)]    = "sr",
 663                 [ilog2(VM_RAND_READ)]   = "rr",
 664                 [ilog2(VM_DONTCOPY)]    = "dc",
 665                 [ilog2(VM_DONTEXPAND)]  = "de",
 666                 [ilog2(VM_ACCOUNT)]     = "ac",
 667                 [ilog2(VM_NORESERVE)]   = "nr",
 668                 [ilog2(VM_HUGETLB)]     = "ht",
 669                 [ilog2(VM_SYNC)]        = "sf",
 670                 [ilog2(VM_ARCH_1)]      = "ar",
 671                 [ilog2(VM_WIPEONFORK)]  = "wf",
 672                 [ilog2(VM_DONTDUMP)]    = "dd",
 673 #ifdef CONFIG_ARM64_BTI
 674                 [ilog2(VM_ARM64_BTI)]   = "bt",
 675 #endif
 676 #ifdef CONFIG_MEM_SOFT_DIRTY
 677                 [ilog2(VM_SOFTDIRTY)]   = "sd",
 678 #endif
 679                 [ilog2(VM_MIXEDMAP)]    = "mm",
 680                 [ilog2(VM_HUGEPAGE)]    = "hg",
 681                 [ilog2(VM_NOHUGEPAGE)]  = "nh",
 682                 [ilog2(VM_MERGEABLE)]   = "mg",
 683                 [ilog2(VM_UFFD_MISSING)]= "um",
 684                 [ilog2(VM_UFFD_WP)]     = "uw",
 685 #ifdef CONFIG_ARM64_MTE
 686                 [ilog2(VM_MTE)]         = "mt",
 687                 [ilog2(VM_MTE_ALLOWED)] = "",
 688 #endif
 689 #ifdef CONFIG_ARCH_HAS_PKEYS
 690                 /* These come out via ProtectionKey: */
 691                 [ilog2(VM_PKEY_BIT0)]   = "",
 692                 [ilog2(VM_PKEY_BIT1)]   = "",
 693                 [ilog2(VM_PKEY_BIT2)]   = "",
 694                 [ilog2(VM_PKEY_BIT3)]   = "",
 695 #if VM_PKEY_BIT4
 696                 [ilog2(VM_PKEY_BIT4)]   = "",
 697 #endif
 698 #endif /* CONFIG_ARCH_HAS_PKEYS */
 699 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
 700                 [ilog2(VM_UFFD_MINOR)]  = "ui",
 701 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
 702         };
 703         size_t i;
 704
 705         seq_puts(m, "VmFlags: ");
 706         for (i = 0; i < BITS_PER_LONG; i++) {
 707                 if (!mnemonics[i][0])
 708                         continue;
 709                 if (vma->vm_flags & (1UL << i)) {
 710                         seq_putc(m, mnemonics[i][0]);
 711                         seq_putc(m, mnemonics[i][1]);
 712                         seq_putc(m, ' ');
 713                 }
 714         }
 715         seq_putc(m, '\n');
 716 }
 717
 718 #ifdef CONFIG_HUGETLB_PAGE
 719 static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 720                                  unsigned long addr, unsigned long end,
 721                                  struct mm_walk *walk)
 722 {
 723         struct mem_size_stats *mss = walk->private;
 724         struct vm_area_struct *vma = walk->vma;
 725         struct page *page = NULL;
 726
 727         if (pte_present(*pte)) {
 728                 page = vm_normal_page(vma, addr, *pte);
 729         } else if (is_swap_pte(*pte)) {
 730                 swp_entry_t swpent = pte_to_swp_entry(*pte);
 731
 732                 if (is_pfn_swap_entry(swpent))
 733                         page = pfn_swap_entry_to_page(swpent);
 734         }
 735         if (page) {
 736                 int mapcount = page_mapcount(page);
 737
 738                 if (mapcount >= 2)
 739                         mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
 740                 else
 741                         mss->private_hugetlb += huge_page_size(hstate_vma(vma));
 742         }
 743         return 0;
 744 }
 745 #else
 746 #define smaps_hugetlb_range     NULL
 747 #endif /* HUGETLB_PAGE */
 748
 749 static const struct mm_walk_ops smaps_walk_ops = {
 750         .pmd_entry              = smaps_pte_range,
 751         .hugetlb_entry          = smaps_hugetlb_range,
 752 };
 753
 754 static const struct mm_walk_ops smaps_shmem_walk_ops = {
 755         .pmd_entry              = smaps_pte_range,
 756         .hugetlb_entry          = smaps_hugetlb_range,
 757         .pte_hole               = smaps_pte_hole,
 758 };
 759
 760 /*
 761  * Gather mem stats from @vma with the indicated beginning
 762  * address @start, and keep them in @mss.
 763  *
 764  * Use vm_start of @vma as the beginning address if @start is 0.
 765  */
 766 static void smap_gather_stats(struct vm_area_struct *vma,
 767                 struct mem_size_stats *mss, unsigned long start)
 768 {
 769         const struct mm_walk_ops *ops = &smaps_walk_ops;
 770
 771         /* Invalid start */
 772         if (start >= vma->vm_end)
 773                 return;
 774
 775 #ifdef CONFIG_SHMEM
 776         if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
 777                 /*
 778                  * For shared or readonly shmem mappings we know that all
 779                  * swapped out pages belong to the shmem object, and we can
 780                  * obtain the swap value much more efficiently. For private
 781                  * writable mappings, we might have COW pages that are
 782                  * not affected by the parent swapped out pages of the shmem
 783                  * object, so we have to distinguish them during the page walk.
 784                  * Unless we know that the shmem object (or the part mapped by
 785                  * our VMA) has no swapped out pages at all.
 786                  */
 787                 unsigned long shmem_swapped = shmem_swap_usage(vma);
 788
 789                 if (!start && (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
 790                                         !(vma->vm_flags & VM_WRITE))) {
 791                         mss->swap += shmem_swapped;
 792                 } else {
 793                         ops = &smaps_shmem_walk_ops;
 794                 }
 795         }
 796 #endif
 797         /* mmap_lock is held in m_start */
 798         if (!start)
 799                 walk_page_vma(vma, ops, mss);
 800         else
 801                 walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
 802 }
 803
 804 #define SEQ_PUT_DEC(str, val) \
 805                 seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 806
 807 /* Show the contents common for smaps and smaps_rollup */
 808 static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
 809         bool rollup_mode)
 810 {
 811         SEQ_PUT_DEC("Rss:            ", mss->resident);
 812         SEQ_PUT_DEC(" kB\nPss:            ", mss->pss >> PSS_SHIFT);
 813         SEQ_PUT_DEC(" kB\nPss_Dirty:      ", mss->pss_dirty >> PSS_SHIFT);
 814         if (rollup_mode) {
 815                 /*
 816                  * These are meaningful only for smaps_rollup, otherwise two of
 817                  * them are zero, and the other one is the same as Pss.
 818                  */
 819                 SEQ_PUT_DEC(" kB\nPss_Anon:       ",
 820                         mss->pss_anon >> PSS_SHIFT);
 821                 SEQ_PUT_DEC(" kB\nPss_File:       ",
 822                         mss->pss_file >> PSS_SHIFT);
 823                 SEQ_PUT_DEC(" kB\nPss_Shmem:      ",
 824                         mss->pss_shmem >> PSS_SHIFT);
 825         }
 826         SEQ_PUT_DEC(" kB\nShared_Clean:   ", mss->shared_clean);
 827         SEQ_PUT_DEC(" kB\nShared_Dirty:   ", mss->shared_dirty);
 828         SEQ_PUT_DEC(" kB\nPrivate_Clean:  ", mss->private_clean);
 829         SEQ_PUT_DEC(" kB\nPrivate_Dirty:  ", mss->private_dirty);
 830         SEQ_PUT_DEC(" kB\nReferenced:     ", mss->referenced);
 831         SEQ_PUT_DEC(" kB\nAnonymous:      ", mss->anonymous);
 832         SEQ_PUT_DEC(" kB\nLazyFree:       ", mss->lazyfree);
 833         SEQ_PUT_DEC(" kB\nAnonHugePages:  ", mss->anonymous_thp);
 834         SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
 835         SEQ_PUT_DEC(" kB\nFilePmdMapped:  ", mss->file_thp);
 836         SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
 837         seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
 838                                   mss->private_hugetlb >> 10, 7);
 839         SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 840         SEQ_PUT_DEC(" kB\nSwapPss:        ",
 841                                         mss->swap_pss >> PSS_SHIFT);
 842         SEQ_PUT_DEC(" kB\nLocked:         ",
 843                                         mss->pss_locked >> PSS_SHIFT);
 844         seq_puts(m, " kB\n");
 845 }
 846
 847 static int show_smap(struct seq_file *m, void *v)
 848 {
 849         struct vm_area_struct *vma = v;
 850         struct mem_size_stats mss;
 851
 852         memset(&mss, 0, sizeof(mss));
 853
 854         smap_gather_stats(vma, &mss, 0);
 855
 856         show_map_vma(m, vma);
 857
 858         SEQ_PUT_DEC("Size:           ", vma->vm_end - vma->vm_start);
 859         SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
 860         SEQ_PUT_DEC(" kB\nMMUPageSize:    ", vma_mmu_pagesize(vma));
 861         seq_puts(m, " kB\n");
 862
 863         __show_smap(m, &mss, false);
 864
 865         seq_printf(m, "THPeligible:    %d\n",
 866                    hugepage_vma_check(vma, vma->vm_flags, true));
 867
 868         if (arch_pkeys_enabled())
 869                 seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
 870         show_smap_vma_flags(m, vma);
 871
 872         return 0;
 873 }
 874
 875 static int show_smaps_rollup(struct seq_file *m, void *v)
 876 {
 877         struct proc_maps_private *priv = m->private;
 878         struct mem_size_stats mss;
 879         struct mm_struct *mm;
 880         struct vm_area_struct *vma;
 881         unsigned long last_vma_end = 0;
 882         int ret = 0;
 883
 884         priv->task = get_proc_task(priv->inode);
 885         if (!priv->task)
 886                 return -ESRCH;
 887
 888         mm = priv->mm;
 889         if (!mm || !mmget_not_zero(mm)) {
 890                 ret = -ESRCH;
 891                 goto out_put_task;
 892         }
 893
 894         memset(&mss, 0, sizeof(mss));
 895
 896         ret = mmap_read_lock_killable(mm);
 897         if (ret)
 898                 goto out_put_mm;
 899
 900         hold_task_mempolicy(priv);
 901
 902         for (vma = priv->mm->mmap; vma;) {
 903                 smap_gather_stats(vma, &mss, 0);
 904                 last_vma_end = vma->vm_end;
 905
 906                 /*
 907                  * Release mmap_lock temporarily if someone wants to
 908                  * access it for write request.
 909                  */
 910                 if (mmap_lock_is_contended(mm)) {
 911                         mmap_read_unlock(mm);
 912                         ret = mmap_read_lock_killable(mm);
 913                         if (ret) {
 914                                 release_task_mempolicy(priv);
 915                                 goto out_put_mm;
 916                         }
 917
 918                         /*
 919                          * After dropping the lock, there are four cases to
 920                          * consider. See the following example for explanation.
 921                          *
 922                          *   +------+------+-----------+
 923                          *   | VMA1 | VMA2 | VMA3      |
 924                          *   +------+------+-----------+
 925                          *   |      |      |           |
 926                          *  4k     8k     16k         400k
 927                          *
 928                          * Suppose we drop the lock after reading VMA2 due to
 929                          * contention, then we get:
 930                          *
 931                          *      last_vma_end = 16k
 932                          *
 933                          * 1) VMA2 is freed, but VMA3 exists:
 934                          *
 935                          *    find_vma(mm, 16k - 1) will return VMA3.
 936                          *    In this case, just continue from VMA3.
 937                          *
 938                          * 2) VMA2 still exists:
 939                          *
 940                          *    find_vma(mm, 16k - 1) will return VMA2.
 941                          *    Iterate the loop like the original one.
 942                          *
 943                          * 3) No more VMAs can be found:
 944                          *
 945                          *    find_vma(mm, 16k - 1) will return NULL.
 946                          *    No more things to do, just break.
 947                          *
 948                          * 4) (last_vma_end - 1) is the middle of a vma (VMA'):
 949                          *
 950                          *    find_vma(mm, 16k - 1) will return VMA' whose range
 951                          *    contains last_vma_end.
 952                          *    Iterate VMA' from last_vma_end.
 953                          */
 954                         vma = find_vma(mm, last_vma_end - 1);
 955                         /* Case 3 above */
 956                         if (!vma)
 957                                 break;
 958
 959                         /* Case 1 above */
 960                         if (vma->vm_start >= last_vma_end)
 961                                 continue;
 962
 963                         /* Case 4 above */
 964                         if (vma->vm_end > last_vma_end)
 965                                 smap_gather_stats(vma, &mss, last_vma_end);
 966                 }
 967                 /* Case 2 above */
 968                 vma = vma->vm_next;
 969         }
 970
 971         show_vma_header_prefix(m, priv->mm->mmap->vm_start,
 972                                last_vma_end, 0, 0, 0, 0);
 973         seq_pad(m, ' ');
 974         seq_puts(m, "[rollup]\n");
 975
 976         __show_smap(m, &mss, true);
 977
 978         release_task_mempolicy(priv);
 979         mmap_read_unlock(mm);
 980
 981 out_put_mm:
 982         mmput(mm);
 983 out_put_task:
 984         put_task_struct(priv->task);
 985         priv->task = NULL;
 986
 987         return ret;
 988 }
 989 #undef SEQ_PUT_DEC
 990
 991 static const struct seq_operations proc_pid_smaps_op = {
 992         .start  = m_start,
 993         .next   = m_next,
 994         .stop   = m_stop,
 995         .show   = show_smap
 996 };
 997
 998 static int pid_smaps_open(struct inode *inode, struct file *file)
 999 {
1000         return do_maps_open(inode, file, &proc_pid_smaps_op);
1001 }
1002
1003 static int smaps_rollup_open(struct inode *inode, struct file *file)
1004 {
1005         int ret;
1006         struct proc_maps_private *priv;
1007
1008         priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
1009         if (!priv)
1010                 return -ENOMEM;
1011
1012         ret = single_open(file, show_smaps_rollup, priv);
1013         if (ret)
1014                 goto out_free;
1015
1016         priv->inode = inode;
1017         priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
1018         if (IS_ERR(priv->mm)) {
1019                 ret = PTR_ERR(priv->mm);
1020
1021                 single_release(inode, file);
1022                 goto out_free;
1023         }
1024
1025         return 0;
1026
1027 out_free:
1028         kfree(priv);
1029         return ret;
1030 }
1031
1032 static int smaps_rollup_release(struct inode *inode, struct file *file)
1033 {
1034         struct seq_file *seq = file->private_data;
1035         struct proc_maps_private *priv = seq->private;
1036
1037         if (priv->mm)
1038                 mmdrop(priv->mm);
1039
1040         kfree(priv);
1041         return single_release(inode, file);
1042 }
1043
1044 const struct file_operations proc_pid_smaps_operations = {
1045         .open           = pid_smaps_open,
1046         .read           = seq_read,
1047         .llseek         = seq_lseek,
1048         .release        = proc_map_release,
1049 };
1050
1051 const struct file_operations proc_pid_smaps_rollup_operations = {
1052         .open           = smaps_rollup_open,
1053         .read           = seq_read,
1054         .llseek         = seq_lseek,
1055         .release        = smaps_rollup_release,
1056 };
1057
1058 enum clear_refs_types {
1059         CLEAR_REFS_ALL = 1,
1060         CLEAR_REFS_ANON,
1061         CLEAR_REFS_MAPPED,
1062         CLEAR_REFS_SOFT_DIRTY,
1063         CLEAR_REFS_MM_HIWATER_RSS,
1064         CLEAR_REFS_LAST,
1065 };
1066
1067 struct clear_refs_private {
1068         enum clear_refs_types type;
1069 };
1070
1071 #ifdef CONFIG_MEM_SOFT_DIRTY
1072
1073 static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1074 {
1075         struct page *page;
1076
1077         if (!pte_write(pte))
1078                 return false;
1079         if (!is_cow_mapping(vma->vm_flags))
1080                 return false;
1081         if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags)))
1082                 return false;
1083         page = vm_normal_page(vma, addr, pte);
1084         if (!page)
1085                 return false;
1086         return page_maybe_dma_pinned(page);
1087 }
1088
1089 static inline void clear_soft_dirty(struct vm_area_struct *vma,
1090                 unsigned long addr, pte_t *pte)
1091 {
1092         /*
1093          * The soft-dirty tracker uses #PF-s to catch writes
1094          * to pages, so write-protect the pte as well. See the
1095          * Documentation/admin-guide/mm/soft-dirty.rst for full description
1096          * of how soft-dirty works.
1097          */
1098         pte_t ptent = *pte;
1099
1100         if (pte_present(ptent)) {
1101                 pte_t old_pte;
1102
1103                 if (pte_is_pinned(vma, addr, ptent))
1104                         return;
1105                 old_pte = ptep_modify_prot_start(vma, addr, pte);
1106                 ptent = pte_wrprotect(old_pte);
1107                 ptent = pte_clear_soft_dirty(ptent);
1108                 ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1109         } else if (is_swap_pte(ptent)) {
1110                 ptent = pte_swp_clear_soft_dirty(ptent);
1111                 set_pte_at(vma->vm_mm, addr, pte, ptent);
1112         }
1113 }
1114 #else
1115 static inline void clear_soft_dirty(struct vm_area_struct *vma,
1116                 unsigned long addr, pte_t *pte)
1117 {
1118 }
1119 #endif
1120
1121 #if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1122 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1123                 unsigned long addr, pmd_t *pmdp)
1124 {
1125         pmd_t old, pmd = *pmdp;
1126
1127         if (pmd_present(pmd)) {
1128                 /* See comment in change_huge_pmd() */
1129                 old = pmdp_invalidate(vma, addr, pmdp);
1130                 if (pmd_dirty(old))
1131                         pmd = pmd_mkdirty(pmd);
1132                 if (pmd_young(old))
1133                         pmd = pmd_mkyoung(pmd);
1134
1135                 pmd = pmd_wrprotect(pmd);
1136                 pmd = pmd_clear_soft_dirty(pmd);
1137
1138                 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1139         } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1140                 pmd = pmd_swp_clear_soft_dirty(pmd);
1141                 set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1142         }
1143 }
1144 #else
1145 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1146                 unsigned long addr, pmd_t *pmdp)
1147 {
1148 }
1149 #endif
1150
1151 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1152                                 unsigned long end, struct mm_walk *walk)
1153 {
1154         struct clear_refs_private *cp = walk->private;
1155         struct vm_area_struct *vma = walk->vma;
1156         pte_t *pte, ptent;
1157         spinlock_t *ptl;
1158         struct page *page;
1159
1160         ptl = pmd_trans_huge_lock(pmd, vma);
1161         if (ptl) {
1162                 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1163                         clear_soft_dirty_pmd(vma, addr, pmd);
1164                         goto out;
1165                 }
1166
1167                 if (!pmd_present(*pmd))
1168                         goto out;
1169
1170                 page = pmd_page(*pmd);
1171
1172                 /* Clear accessed and referenced bits. */
1173                 pmdp_test_and_clear_young(vma, addr, pmd);
1174                 test_and_clear_page_young(page);
1175                 ClearPageReferenced(page);
1176 out:
1177                 spin_unlock(ptl);
1178                 return 0;
1179         }
1180
1181         if (pmd_trans_unstable(pmd))
1182                 return 0;
1183
1184         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1185         for (; addr != end; pte++, addr += PAGE_SIZE) {
1186                 ptent = *pte;
1187
1188                 if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1189                         clear_soft_dirty(vma, addr, pte);
1190                         continue;
1191                 }
1192
1193                 if (!pte_present(ptent))
1194                         continue;
1195
1196                 page = vm_normal_page(vma, addr, ptent);
1197                 if (!page)
1198                         continue;
1199
1200                 /* Clear accessed and referenced bits. */
1201                 ptep_test_and_clear_young(vma, addr, pte);
1202                 test_and_clear_page_young(page);
1203                 ClearPageReferenced(page);
1204         }
1205         pte_unmap_unlock(pte - 1, ptl);
1206         cond_resched();
1207         return 0;
1208 }
1209
1210 static int clear_refs_test_walk(unsigned long start, unsigned long end,
1211                                 struct mm_walk *walk)
1212 {
1213         struct clear_refs_private *cp = walk->private;
1214         struct vm_area_struct *vma = walk->vma;
1215
1216         if (vma->vm_flags & VM_PFNMAP)
1217                 return 1;
1218
1219         /*
1220          * Writing 1 to /proc/pid/clear_refs affects all pages.
1221          * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1222          * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1223          * Writing 4 to /proc/pid/clear_refs affects all pages.
1224          */
1225         if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1226                 return 1;
1227         if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1228                 return 1;
1229         return 0;
1230 }
1231
1232 static const struct mm_walk_ops clear_refs_walk_ops = {
1233         .pmd_entry              = clear_refs_pte_range,
1234         .test_walk              = clear_refs_test_walk,
1235 };
1236
1237 static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1238                                 size_t count, loff_t *ppos)
1239 {
1240         struct task_struct *task;
1241         char buffer[PROC_NUMBUF];
1242         struct mm_struct *mm;
1243         struct vm_area_struct *vma;
1244         enum clear_refs_types type;
1245         int itype;
1246         int rv;
1247
1248         memset(buffer, 0, sizeof(buffer));
1249         if (count > sizeof(buffer) - 1)
1250                 count = sizeof(buffer) - 1;
1251         if (copy_from_user(buffer, buf, count))
1252                 return -EFAULT;
1253         rv = kstrtoint(strstrip(buffer), 10, &itype);
1254         if (rv < 0)
1255                 return rv;
1256         type = (enum clear_refs_types)itype;
1257         if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1258                 return -EINVAL;
1259
1260         task = get_proc_task(file_inode(file));
1261         if (!task)
1262                 return -ESRCH;
1263         mm = get_task_mm(task);
1264         if (mm) {
1265                 struct mmu_notifier_range range;
1266                 struct clear_refs_private cp = {
1267                         .type = type,
1268                 };
1269
1270                 if (mmap_write_lock_killable(mm)) {
1271                         count = -EINTR;
1272                         goto out_mm;
1273                 }
1274                 if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1275                         /*
1276                          * Writing 5 to /proc/pid/clear_refs resets the peak
1277                          * resident set size to this mm's current rss value.
1278                          */
1279                         reset_mm_hiwater_rss(mm);
1280                         goto out_unlock;
1281                 }
1282
1283                 if (type == CLEAR_REFS_SOFT_DIRTY) {
1284                         for (vma = mm->mmap; vma; vma = vma->vm_next) {
1285                                 if (!(vma->vm_flags & VM_SOFTDIRTY))
1286                                         continue;
1287                                 vma->vm_flags &= ~VM_SOFTDIRTY;
1288                                 vma_set_page_prot(vma);
1289                         }
1290
1291                         inc_tlb_flush_pending(mm);
1292                         mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1293                                                 0, NULL, mm, 0, -1UL);
1294                         mmu_notifier_invalidate_range_start(&range);
1295                 }
1296                 walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops,
1297                                 &cp);
1298                 if (type == CLEAR_REFS_SOFT_DIRTY) {
1299                         mmu_notifier_invalidate_range_end(&range);
1300                         flush_tlb_mm(mm);
1301                         dec_tlb_flush_pending(mm);
1302                 }
1303 out_unlock:
1304                 mmap_write_unlock(mm);
1305 out_mm:
1306                 mmput(mm);
1307         }
1308         put_task_struct(task);
1309
1310         return count;
1311 }
1312
1313 const struct file_operations proc_clear_refs_operations = {
1314         .write          = clear_refs_write,
1315         .llseek         = noop_llseek,
1316 };
1317
1318 typedef struct {
1319         u64 pme;
1320 } pagemap_entry_t;
1321
1322 struct pagemapread {
1323         int pos, len;           /* units: PM_ENTRY_BYTES, not bytes */
1324         pagemap_entry_t *buffer;
1325         bool show_pfn;
1326 };
1327
1328 #define PAGEMAP_WALK_SIZE       (PMD_SIZE)
1329 #define PAGEMAP_WALK_MASK       (PMD_MASK)
1330
1331 #define PM_ENTRY_BYTES          sizeof(pagemap_entry_t)
1332 #define PM_PFRAME_BITS          55
1333 #define PM_PFRAME_MASK          GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1334 #define PM_SOFT_DIRTY           BIT_ULL(55)
1335 #define PM_MMAP_EXCLUSIVE       BIT_ULL(56)
1336 #define PM_UFFD_WP              BIT_ULL(57)
1337 #define PM_FILE                 BIT_ULL(61)
1338 #define PM_SWAP                 BIT_ULL(62)
1339 #define PM_PRESENT              BIT_ULL(63)
1340
1341 #define PM_END_OF_BUFFER    1
1342
1343 static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1344 {
1345         return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1346 }
1347
1348 static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1349                           struct pagemapread *pm)
1350 {
1351         pm->buffer[pm->pos++] = *pme;
1352         if (pm->pos >= pm->len)
1353                 return PM_END_OF_BUFFER;
1354         return 0;
1355 }
1356
1357 static int pagemap_pte_hole(unsigned long start, unsigned long end,
1358                             __always_unused int depth, struct mm_walk *walk)
1359 {
1360         struct pagemapread *pm = walk->private;
1361         unsigned long addr = start;
1362         int err = 0;
1363
1364         while (addr < end) {
1365                 struct vm_area_struct *vma = find_vma(walk->mm, addr);
1366                 pagemap_entry_t pme = make_pme(0, 0);
1367                 /* End of address space hole, which we mark as non-present. */
1368                 unsigned long hole_end;
1369
1370                 if (vma)
1371                         hole_end = min(end, vma->vm_start);
1372                 else
1373                         hole_end = end;
1374
1375                 for (; addr < hole_end; addr += PAGE_SIZE) {
1376                         err = add_to_pagemap(addr, &pme, pm);
1377                         if (err)
1378                                 goto out;
1379                 }
1380
1381                 if (!vma)
1382                         break;
1383
1384                 /* Addresses in the VMA. */
1385                 if (vma->vm_flags & VM_SOFTDIRTY)
1386                         pme = make_pme(0, PM_SOFT_DIRTY);
1387                 for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1388                         err = add_to_pagemap(addr, &pme, pm);
1389                         if (err)
1390                                 goto out;
1391                 }
1392         }
1393 out:
1394         return err;
1395 }
1396
1397 static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1398                 struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1399 {
1400         u64 frame = 0, flags = 0;
1401         struct page *page = NULL;
1402         bool migration = false;
1403
1404         if (pte_present(pte)) {
1405                 if (pm->show_pfn)
1406                         frame = pte_pfn(pte);
1407                 flags |= PM_PRESENT;
1408                 page = vm_normal_page(vma, addr, pte);
1409                 if (pte_soft_dirty(pte))
1410                         flags |= PM_SOFT_DIRTY;
1411                 if (pte_uffd_wp(pte))
1412                         flags |= PM_UFFD_WP;
1413         } else if (is_swap_pte(pte)) {
1414                 swp_entry_t entry;
1415                 if (pte_swp_soft_dirty(pte))
1416                         flags |= PM_SOFT_DIRTY;
1417                 if (pte_swp_uffd_wp(pte))
1418                         flags |= PM_UFFD_WP;
1419                 entry = pte_to_swp_entry(pte);
1420                 if (pm->show_pfn)
1421                         frame = swp_type(entry) |
1422                                 (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1423                 flags |= PM_SWAP;
1424                 migration = is_migration_entry(entry);
1425                 if (is_pfn_swap_entry(entry))
1426                         page = pfn_swap_entry_to_page(entry);
1427                 if (pte_marker_entry_uffd_wp(entry))
1428                         flags |= PM_UFFD_WP;
1429         }
1430
1431         if (page && !PageAnon(page))
1432                 flags |= PM_FILE;
1433         if (page && !migration && page_mapcount(page) == 1)
1434                 flags |= PM_MMAP_EXCLUSIVE;
1435         if (vma->vm_flags & VM_SOFTDIRTY)
1436                 flags |= PM_SOFT_DIRTY;
1437
1438         return make_pme(frame, flags);
1439 }
1440
1441 static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1442                              struct mm_walk *walk)
1443 {
1444         struct vm_area_struct *vma = walk->vma;
1445         struct pagemapread *pm = walk->private;
1446         spinlock_t *ptl;
1447         pte_t *pte, *orig_pte;
1448         int err = 0;
1449 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1450         bool migration = false;
1451
1452         ptl = pmd_trans_huge_lock(pmdp, vma);
1453         if (ptl) {
1454                 u64 flags = 0, frame = 0;
1455                 pmd_t pmd = *pmdp;
1456                 struct page *page = NULL;
1457
1458                 if (vma->vm_flags & VM_SOFTDIRTY)
1459                         flags |= PM_SOFT_DIRTY;
1460
1461                 if (pmd_present(pmd)) {
1462                         page = pmd_page(pmd);
1463
1464                         flags |= PM_PRESENT;
1465                         if (pmd_soft_dirty(pmd))
1466                                 flags |= PM_SOFT_DIRTY;
1467                         if (pmd_uffd_wp(pmd))
1468                                 flags |= PM_UFFD_WP;
1469                         if (pm->show_pfn)
1470                                 frame = pmd_pfn(pmd) +
1471                                         ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1472                 }
1473 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1474                 else if (is_swap_pmd(pmd)) {
1475                         swp_entry_t entry = pmd_to_swp_entry(pmd);
1476                         unsigned long offset;
1477
1478                         if (pm->show_pfn) {
1479                                 offset = swp_offset(entry) +
1480                                         ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1481                                 frame = swp_type(entry) |
1482                                         (offset << MAX_SWAPFILES_SHIFT);
1483                         }
1484                         flags |= PM_SWAP;
1485                         if (pmd_swp_soft_dirty(pmd))
1486                                 flags |= PM_SOFT_DIRTY;
1487                         if (pmd_swp_uffd_wp(pmd))
1488                                 flags |= PM_UFFD_WP;
1489                         VM_BUG_ON(!is_pmd_migration_entry(pmd));
1490                         migration = is_migration_entry(entry);
1491                         page = pfn_swap_entry_to_page(entry);
1492                 }
1493 #endif
1494
1495                 if (page && !migration && page_mapcount(page) == 1)
1496                         flags |= PM_MMAP_EXCLUSIVE;
1497
1498                 for (; addr != end; addr += PAGE_SIZE) {
1499                         pagemap_entry_t pme = make_pme(frame, flags);
1500
1501                         err = add_to_pagemap(addr, &pme, pm);
1502                         if (err)
1503                                 break;
1504                         if (pm->show_pfn) {
1505                                 if (flags & PM_PRESENT)
1506                                         frame++;
1507                                 else if (flags & PM_SWAP)
1508                                         frame += (1 << MAX_SWAPFILES_SHIFT);
1509                         }
1510                 }
1511                 spin_unlock(ptl);
1512                 return err;
1513         }
1514
1515         if (pmd_trans_unstable(pmdp))
1516                 return 0;
1517 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1518
1519         /*
1520          * We can assume that @vma always points to a valid one and @end never
1521          * goes beyond vma->vm_end.
1522          */
1523         orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1524         for (; addr < end; pte++, addr += PAGE_SIZE) {
1525                 pagemap_entry_t pme;
1526
1527                 pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1528                 err = add_to_pagemap(addr, &pme, pm);
1529                 if (err)
1530                         break;
1531         }
1532         pte_unmap_unlock(orig_pte, ptl);
1533
1534         cond_resched();
1535
1536         return err;
1537 }
1538
1539 #ifdef CONFIG_HUGETLB_PAGE
1540 /* This function walks within one hugetlb entry in the single call */
1541 static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1542                                  unsigned long addr, unsigned long end,
1543                                  struct mm_walk *walk)
1544 {
1545         struct pagemapread *pm = walk->private;
1546         struct vm_area_struct *vma = walk->vma;
1547         u64 flags = 0, frame = 0;
1548         int err = 0;
1549         pte_t pte;
1550
1551         if (vma->vm_flags & VM_SOFTDIRTY)
1552                 flags |= PM_SOFT_DIRTY;
1553
1554         pte = huge_ptep_get(ptep);
1555         if (pte_present(pte)) {
1556                 struct page *page = pte_page(pte);
1557
1558                 if (!PageAnon(page))
1559                         flags |= PM_FILE;
1560
1561                 if (page_mapcount(page) == 1)
1562                         flags |= PM_MMAP_EXCLUSIVE;
1563
1564                 if (huge_pte_uffd_wp(pte))
1565                         flags |= PM_UFFD_WP;
1566
1567                 flags |= PM_PRESENT;
1568                 if (pm->show_pfn)
1569                         frame = pte_pfn(pte) +
1570                                 ((addr & ~hmask) >> PAGE_SHIFT);
1571         } else if (pte_swp_uffd_wp_any(pte)) {
1572                 flags |= PM_UFFD_WP;
1573         }
1574
1575         for (; addr != end; addr += PAGE_SIZE) {
1576                 pagemap_entry_t pme = make_pme(frame, flags);
1577
1578                 err = add_to_pagemap(addr, &pme, pm);
1579                 if (err)
1580                         return err;
1581                 if (pm->show_pfn && (flags & PM_PRESENT))
1582                         frame++;
1583         }
1584
1585         cond_resched();
1586
1587         return err;
1588 }
1589 #else
1590 #define pagemap_hugetlb_range   NULL
1591 #endif /* HUGETLB_PAGE */
1592
1593 static const struct mm_walk_ops pagemap_ops = {
1594         .pmd_entry      = pagemap_pmd_range,
1595         .pte_hole       = pagemap_pte_hole,
1596         .hugetlb_entry  = pagemap_hugetlb_range,
1597 };
1598
1599 /*
1600  * /proc/pid/pagemap - an array mapping virtual pages to pfns
1601  *
1602  * For each page in the address space, this file contains one 64-bit entry
1603  * consisting of the following:
1604  *
1605  * Bits 0-54  page frame number (PFN) if present
1606  * Bits 0-4   swap type if swapped
1607  * Bits 5-54  swap offset if swapped
1608  * Bit  55    pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1609  * Bit  56    page exclusively mapped
1610  * Bit  57    pte is uffd-wp write-protected
1611  * Bits 58-60 zero
1612  * Bit  61    page is file-page or shared-anon
1613  * Bit  62    page swapped
1614  * Bit  63    page present
1615  *
1616  * If the page is not present but in swap, then the PFN contains an
1617  * encoding of the swap file number and the page's offset into the
1618  * swap. Unmapped pages return a null PFN. This allows determining
1619  * precisely which pages are mapped (or in swap) and comparing mapped
1620  * pages between processes.
1621  *
1622  * Efficient users of this interface will use /proc/pid/maps to
1623  * determine which areas of memory are actually mapped and llseek to
1624  * skip over unmapped regions.
1625  */
1626 static ssize_t pagemap_read(struct file *file, char __user *buf,
1627                             size_t count, loff_t *ppos)
1628 {
1629         struct mm_struct *mm = file->private_data;
1630         struct pagemapread pm;
1631         unsigned long src;
1632         unsigned long svpfn;
1633         unsigned long start_vaddr;
1634         unsigned long end_vaddr;
1635         int ret = 0, copied = 0;
1636
1637         if (!mm || !mmget_not_zero(mm))
1638                 goto out;
1639
1640         ret = -EINVAL;
1641         /* file position must be aligned */
1642         if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1643                 goto out_mm;
1644
1645         ret = 0;
1646         if (!count)
1647                 goto out_mm;
1648
1649         /* do not disclose physical addresses: attack vector */
1650         pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1651
1652         pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1653         pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1654         ret = -ENOMEM;
1655         if (!pm.buffer)
1656                 goto out_mm;
1657
1658         src = *ppos;
1659         svpfn = src / PM_ENTRY_BYTES;
1660         end_vaddr = mm->task_size;
1661
1662         /* watch out for wraparound */
1663         start_vaddr = end_vaddr;
1664         if (svpfn <= (ULONG_MAX >> PAGE_SHIFT))
1665                 start_vaddr = untagged_addr(svpfn << PAGE_SHIFT);
1666
1667         /* Ensure the address is inside the task */
1668         if (start_vaddr > mm->task_size)
1669                 start_vaddr = end_vaddr;
1670
1671         /*
1672          * The odds are that this will stop walking way
1673          * before end_vaddr, because the length of the
1674          * user buffer is tracked in "pm", and the walk
1675          * will stop when we hit the end of the buffer.
1676          */
1677         ret = 0;
1678         while (count && (start_vaddr < end_vaddr)) {
1679                 int len;
1680                 unsigned long end;
1681
1682                 pm.pos = 0;
1683                 end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1684                 /* overflow ? */
1685                 if (end < start_vaddr || end > end_vaddr)
1686                         end = end_vaddr;
1687                 ret = mmap_read_lock_killable(mm);
1688                 if (ret)
1689                         goto out_free;
1690                 ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1691                 mmap_read_unlock(mm);
1692                 start_vaddr = end;
1693
1694                 len = min(count, PM_ENTRY_BYTES * pm.pos);
1695                 if (copy_to_user(buf, pm.buffer, len)) {
1696                         ret = -EFAULT;
1697                         goto out_free;
1698                 }
1699                 copied += len;
1700                 buf += len;
1701                 count -= len;
1702         }
1703         *ppos += copied;
1704         if (!ret || ret == PM_END_OF_BUFFER)
1705                 ret = copied;
1706
1707 out_free:
1708         kfree(pm.buffer);
1709 out_mm:
1710         mmput(mm);
1711 out:
1712         return ret;
1713 }
1714
1715 static int pagemap_open(struct inode *inode, struct file *file)
1716 {
1717         struct mm_struct *mm;
1718
1719         mm = proc_mem_open(inode, PTRACE_MODE_READ);
1720         if (IS_ERR(mm))
1721                 return PTR_ERR(mm);
1722         file->private_data = mm;
1723         return 0;
1724 }
1725
1726 static int pagemap_release(struct inode *inode, struct file *file)
1727 {
1728         struct mm_struct *mm = file->private_data;
1729
1730         if (mm)
1731                 mmdrop(mm);
1732         return 0;
1733 }
1734
1735 const struct file_operations proc_pagemap_operations = {
1736         .llseek         = mem_lseek, /* borrow this */
1737         .read           = pagemap_read,
1738         .open           = pagemap_open,
1739         .release        = pagemap_release,
1740 };
1741 #endif /* CONFIG_PROC_PAGE_MONITOR */
1742
1743 #ifdef CONFIG_NUMA
1744
1745 struct numa_maps {
1746         unsigned long pages;
1747         unsigned long anon;
1748         unsigned long active;
1749         unsigned long writeback;
1750         unsigned long mapcount_max;
1751         unsigned long dirty;
1752         unsigned long swapcache;
1753         unsigned long node[MAX_NUMNODES];
1754 };
1755
1756 struct numa_maps_private {
1757         struct proc_maps_private proc_maps;
1758         struct numa_maps md;
1759 };
1760
1761 static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1762                         unsigned long nr_pages)
1763 {
1764         int count = page_mapcount(page);
1765
1766         md->pages += nr_pages;
1767         if (pte_dirty || PageDirty(page))
1768                 md->dirty += nr_pages;
1769
1770         if (PageSwapCache(page))
1771                 md->swapcache += nr_pages;
1772
1773         if (PageActive(page) || PageUnevictable(page))
1774                 md->active += nr_pages;
1775
1776         if (PageWriteback(page))
1777                 md->writeback += nr_pages;
1778
1779         if (PageAnon(page))
1780                 md->anon += nr_pages;
1781
1782         if (count > md->mapcount_max)
1783                 md->mapcount_max = count;
1784
1785         md->node[page_to_nid(page)] += nr_pages;
1786 }
1787
1788 static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1789                 unsigned long addr)
1790 {
1791         struct page *page;
1792         int nid;
1793
1794         if (!pte_present(pte))
1795                 return NULL;
1796
1797         page = vm_normal_page(vma, addr, pte);
1798         if (!page || is_zone_device_page(page))
1799                 return NULL;
1800
1801         if (PageReserved(page))
1802                 return NULL;
1803
1804         nid = page_to_nid(page);
1805         if (!node_isset(nid, node_states[N_MEMORY]))
1806                 return NULL;
1807
1808         return page;
1809 }
1810
1811 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1812 static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1813                                               struct vm_area_struct *vma,
1814                                               unsigned long addr)
1815 {
1816         struct page *page;
1817         int nid;
1818
1819         if (!pmd_present(pmd))
1820                 return NULL;
1821
1822         page = vm_normal_page_pmd(vma, addr, pmd);
1823         if (!page)
1824                 return NULL;
1825
1826         if (PageReserved(page))
1827                 return NULL;
1828
1829         nid = page_to_nid(page);
1830         if (!node_isset(nid, node_states[N_MEMORY]))
1831                 return NULL;
1832
1833         return page;
1834 }
1835 #endif
1836
1837 static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1838                 unsigned long end, struct mm_walk *walk)
1839 {
1840         struct numa_maps *md = walk->private;
1841         struct vm_area_struct *vma = walk->vma;
1842         spinlock_t *ptl;
1843         pte_t *orig_pte;
1844         pte_t *pte;
1845
1846 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1847         ptl = pmd_trans_huge_lock(pmd, vma);
1848         if (ptl) {
1849                 struct page *page;
1850
1851                 page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1852                 if (page)
1853                         gather_stats(page, md, pmd_dirty(*pmd),
1854                                      HPAGE_PMD_SIZE/PAGE_SIZE);
1855                 spin_unlock(ptl);
1856                 return 0;
1857         }
1858
1859         if (pmd_trans_unstable(pmd))
1860                 return 0;
1861 #endif
1862         orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1863         do {
1864                 struct page *page = can_gather_numa_stats(*pte, vma, addr);
1865                 if (!page)
1866                         continue;
1867                 gather_stats(page, md, pte_dirty(*pte), 1);
1868
1869         } while (pte++, addr += PAGE_SIZE, addr != end);
1870         pte_unmap_unlock(orig_pte, ptl);
1871         cond_resched();
1872         return 0;
1873 }
1874 #ifdef CONFIG_HUGETLB_PAGE
1875 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1876                 unsigned long addr, unsigned long end, struct mm_walk *walk)
1877 {
1878         pte_t huge_pte = huge_ptep_get(pte);
1879         struct numa_maps *md;
1880         struct page *page;
1881
1882         if (!pte_present(huge_pte))
1883                 return 0;
1884
1885         page = pte_page(huge_pte);
1886
1887         md = walk->private;
1888         gather_stats(page, md, pte_dirty(huge_pte), 1);
1889         return 0;
1890 }
1891
1892 #else
1893 static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1894                 unsigned long addr, unsigned long end, struct mm_walk *walk)
1895 {
1896         return 0;
1897 }
1898 #endif
1899
1900 static const struct mm_walk_ops show_numa_ops = {
1901         .hugetlb_entry = gather_hugetlb_stats,
1902         .pmd_entry = gather_pte_stats,
1903 };
1904
1905 /*
1906  * Display pages allocated per node and memory policy via /proc.
1907  */
1908 static int show_numa_map(struct seq_file *m, void *v)
1909 {
1910         struct numa_maps_private *numa_priv = m->private;
1911         struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1912         struct vm_area_struct *vma = v;
1913         struct numa_maps *md = &numa_priv->md;
1914         struct file *file = vma->vm_file;
1915         struct mm_struct *mm = vma->vm_mm;
1916         struct mempolicy *pol;
1917         char buffer[64];
1918         int nid;
1919
1920         if (!mm)
1921                 return 0;
1922
1923         /* Ensure we start with an empty set of numa_maps statistics. */
1924         memset(md, 0, sizeof(*md));
1925
1926         pol = __get_vma_policy(vma, vma->vm_start);
1927         if (pol) {
1928                 mpol_to_str(buffer, sizeof(buffer), pol);
1929                 mpol_cond_put(pol);
1930         } else {
1931                 mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1932         }
1933
1934         seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1935
1936         if (file) {
1937                 seq_puts(m, " file=");
1938                 seq_file_path(m, file, "\n\t= ");
1939         } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1940                 seq_puts(m, " heap");
1941         } else if (is_stack(vma)) {
1942                 seq_puts(m, " stack");
1943         }
1944
1945         if (is_vm_hugetlb_page(vma))
1946                 seq_puts(m, " huge");
1947
1948         /* mmap_lock is held by m_start */
1949         walk_page_vma(vma, &show_numa_ops, md);
1950
1951         if (!md->pages)
1952                 goto out;
1953
1954         if (md->anon)
1955                 seq_printf(m, " anon=%lu", md->anon);
1956
1957         if (md->dirty)
1958                 seq_printf(m, " dirty=%lu", md->dirty);
1959
1960         if (md->pages != md->anon && md->pages != md->dirty)
1961                 seq_printf(m, " mapped=%lu", md->pages);
1962
1963         if (md->mapcount_max > 1)
1964                 seq_printf(m, " mapmax=%lu", md->mapcount_max);
1965
1966         if (md->swapcache)
1967                 seq_printf(m, " swapcache=%lu", md->swapcache);
1968
1969         if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1970                 seq_printf(m, " active=%lu", md->active);
1971
1972         if (md->writeback)
1973                 seq_printf(m, " writeback=%lu", md->writeback);
1974
1975         for_each_node_state(nid, N_MEMORY)
1976                 if (md->node[nid])
1977                         seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1978
1979         seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1980 out:
1981         seq_putc(m, '\n');
1982         return 0;
1983 }
1984
1985 static const struct seq_operations proc_pid_numa_maps_op = {
1986         .start  = m_start,
1987         .next   = m_next,
1988         .stop   = m_stop,
1989         .show   = show_numa_map,
1990 };
1991
1992 static int pid_numa_maps_open(struct inode *inode, struct file *file)
1993 {
1994         return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
1995                                 sizeof(struct numa_maps_private));
1996 }
1997
1998 const struct file_operations proc_pid_numa_maps_operations = {
1999         .open           = pid_numa_maps_open,
2000         .read           = seq_read,
2001         .llseek         = seq_lseek,
2002         .release        = proc_map_release,
2003 };
2004
2005 #endif /* CONFIG_NUMA */