linux/fs/proc/task_mmu.c
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   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)
  30void 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
  82unsigned long task_vsize(struct mm_struct *mm)
  83{
  84        return PAGE_SIZE * mm->total_vm;
  85}
  86
  87unsigned 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 */
 104static 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}
 113static void release_task_mempolicy(struct proc_maps_private *priv)
 114{
 115        mpol_put(priv->task_mempolicy);
 116}
 117#else
 118static void hold_task_mempolicy(struct proc_maps_private *priv)
 119{
 120}
 121static void release_task_mempolicy(struct proc_maps_private *priv)
 122{
 123}
 124#endif
 125
 126static 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
 165static 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
 182static 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
 197static 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
 217static 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
 228static 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 */
 239static 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
 250static 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
 270static void
 271show_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
 326done:
 327        if (name) {
 328                seq_pad(m, ' ');
 329                seq_puts(m, name);
 330        }
 331        seq_putc(m, '\n');
 332}
 333
 334static int show_map(struct seq_file *m, void *v)
 335{
 336        show_map_vma(m, v);
 337        return 0;
 338}
 339
 340static 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
 347static int pid_maps_open(struct inode *inode, struct file *file)
 348{
 349        return do_maps_open(inode, file, &proc_pid_maps_op);
 350}
 351
 352const 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
 379struct mem_size_stats {
 380        unsigned long resident;
 381        unsigned long shared_clean;
 382        unsigned long shared_dirty;
 383        unsigned long private_clean;
 384        unsigned long private_dirty;
 385        unsigned long referenced;
 386        unsigned long anonymous;
 387        unsigned long lazyfree;
 388        unsigned long anonymous_thp;
 389        unsigned long shmem_thp;
 390        unsigned long file_thp;
 391        unsigned long swap;
 392        unsigned long shared_hugetlb;
 393        unsigned long private_hugetlb;
 394        u64 pss;
 395        u64 pss_anon;
 396        u64 pss_file;
 397        u64 pss_shmem;
 398        u64 pss_locked;
 399        u64 swap_pss;
 400        bool check_shmem_swap;
 401};
 402
 403static void smaps_page_accumulate(struct mem_size_stats *mss,
 404                struct page *page, unsigned long size, unsigned long pss,
 405                bool dirty, bool locked, bool private)
 406{
 407        mss->pss += pss;
 408
 409        if (PageAnon(page))
 410                mss->pss_anon += pss;
 411        else if (PageSwapBacked(page))
 412                mss->pss_shmem += pss;
 413        else
 414                mss->pss_file += pss;
 415
 416        if (locked)
 417                mss->pss_locked += pss;
 418
 419        if (dirty || PageDirty(page)) {
 420                if (private)
 421                        mss->private_dirty += size;
 422                else
 423                        mss->shared_dirty += size;
 424        } else {
 425                if (private)
 426                        mss->private_clean += size;
 427                else
 428                        mss->shared_clean += size;
 429        }
 430}
 431
 432static void smaps_account(struct mem_size_stats *mss, struct page *page,
 433                bool compound, bool young, bool dirty, bool locked)
 434{
 435        int i, nr = compound ? compound_nr(page) : 1;
 436        unsigned long size = nr * PAGE_SIZE;
 437
 438        /*
 439         * First accumulate quantities that depend only on |size| and the type
 440         * of the compound page.
 441         */
 442        if (PageAnon(page)) {
 443                mss->anonymous += size;
 444                if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
 445                        mss->lazyfree += size;
 446        }
 447
 448        mss->resident += size;
 449        /* Accumulate the size in pages that have been accessed. */
 450        if (young || page_is_young(page) || PageReferenced(page))
 451                mss->referenced += size;
 452
 453        /*
 454         * Then accumulate quantities that may depend on sharing, or that may
 455         * differ page-by-page.
 456         *
 457         * page_count(page) == 1 guarantees the page is mapped exactly once.
 458         * If any subpage of the compound page mapped with PTE it would elevate
 459         * page_count().
 460         */
 461        if (page_count(page) == 1) {
 462                smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
 463                        locked, true);
 464                return;
 465        }
 466        for (i = 0; i < nr; i++, page++) {
 467                int mapcount = page_mapcount(page);
 468                unsigned long pss = PAGE_SIZE << PSS_SHIFT;
 469                if (mapcount >= 2)
 470                        pss /= mapcount;
 471                smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
 472                                      mapcount < 2);
 473        }
 474}
 475
 476#ifdef CONFIG_SHMEM
 477static int smaps_pte_hole(unsigned long addr, unsigned long end,
 478                          __always_unused int depth, struct mm_walk *walk)
 479{
 480        struct mem_size_stats *mss = walk->private;
 481
 482        mss->swap += shmem_partial_swap_usage(
 483                        walk->vma->vm_file->f_mapping, addr, end);
 484
 485        return 0;
 486}
 487#else
 488#define smaps_pte_hole          NULL
 489#endif /* CONFIG_SHMEM */
 490
 491static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 492                struct mm_walk *walk)
 493{
 494        struct mem_size_stats *mss = walk->private;
 495        struct vm_area_struct *vma = walk->vma;
 496        bool locked = !!(vma->vm_flags & VM_LOCKED);
 497        struct page *page = NULL;
 498
 499        if (pte_present(*pte)) {
 500                page = vm_normal_page(vma, addr, *pte);
 501        } else if (is_swap_pte(*pte)) {
 502                swp_entry_t swpent = pte_to_swp_entry(*pte);
 503
 504                if (!non_swap_entry(swpent)) {
 505                        int mapcount;
 506
 507                        mss->swap += PAGE_SIZE;
 508                        mapcount = swp_swapcount(swpent);
 509                        if (mapcount >= 2) {
 510                                u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
 511
 512                                do_div(pss_delta, mapcount);
 513                                mss->swap_pss += pss_delta;
 514                        } else {
 515                                mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 516                        }
 517                } else if (is_migration_entry(swpent))
 518                        page = migration_entry_to_page(swpent);
 519                else if (is_device_private_entry(swpent))
 520                        page = device_private_entry_to_page(swpent);
 521        } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
 522                                                        && pte_none(*pte))) {
 523                page = xa_load(&vma->vm_file->f_mapping->i_pages,
 524                                                linear_page_index(vma, addr));
 525                if (xa_is_value(page))
 526                        mss->swap += PAGE_SIZE;
 527                return;
 528        }
 529
 530        if (!page)
 531                return;
 532
 533        smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked);
 534}
 535
 536#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 537static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 538                struct mm_walk *walk)
 539{
 540        struct mem_size_stats *mss = walk->private;
 541        struct vm_area_struct *vma = walk->vma;
 542        bool locked = !!(vma->vm_flags & VM_LOCKED);
 543        struct page *page = NULL;
 544
 545        if (pmd_present(*pmd)) {
 546                /* FOLL_DUMP will return -EFAULT on huge zero page */
 547                page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
 548        } else if (unlikely(thp_migration_supported() && is_swap_pmd(*pmd))) {
 549                swp_entry_t entry = pmd_to_swp_entry(*pmd);
 550
 551                if (is_migration_entry(entry))
 552                        page = migration_entry_to_page(entry);
 553        }
 554        if (IS_ERR_OR_NULL(page))
 555                return;
 556        if (PageAnon(page))
 557                mss->anonymous_thp += HPAGE_PMD_SIZE;
 558        else if (PageSwapBacked(page))
 559                mss->shmem_thp += HPAGE_PMD_SIZE;
 560        else if (is_zone_device_page(page))
 561                /* pass */;
 562        else
 563                mss->file_thp += HPAGE_PMD_SIZE;
 564        smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked);
 565}
 566#else
 567static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 568                struct mm_walk *walk)
 569{
 570}
 571#endif
 572
 573static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 574                           struct mm_walk *walk)
 575{
 576        struct vm_area_struct *vma = walk->vma;
 577        pte_t *pte;
 578        spinlock_t *ptl;
 579
 580        ptl = pmd_trans_huge_lock(pmd, vma);
 581        if (ptl) {
 582                smaps_pmd_entry(pmd, addr, walk);
 583                spin_unlock(ptl);
 584                goto out;
 585        }
 586
 587        if (pmd_trans_unstable(pmd))
 588                goto out;
 589        /*
 590         * The mmap_lock held all the way back in m_start() is what
 591         * keeps khugepaged out of here and from collapsing things
 592         * in here.
 593         */
 594        pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 595        for (; addr != end; pte++, addr += PAGE_SIZE)
 596                smaps_pte_entry(pte, addr, walk);
 597        pte_unmap_unlock(pte - 1, ptl);
 598out:
 599        cond_resched();
 600        return 0;
 601}
 602
 603static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 604{
 605        /*
 606         * Don't forget to update Documentation/ on changes.
 607         */
 608        static const char mnemonics[BITS_PER_LONG][2] = {
 609                /*
 610                 * In case if we meet a flag we don't know about.
 611                 */
 612                [0 ... (BITS_PER_LONG-1)] = "??",
 613
 614                [ilog2(VM_READ)]        = "rd",
 615                [ilog2(VM_WRITE)]       = "wr",
 616                [ilog2(VM_EXEC)]        = "ex",
 617                [ilog2(VM_SHARED)]      = "sh",
 618                [ilog2(VM_MAYREAD)]     = "mr",
 619                [ilog2(VM_MAYWRITE)]    = "mw",
 620                [ilog2(VM_MAYEXEC)]     = "me",
 621                [ilog2(VM_MAYSHARE)]    = "ms",
 622                [ilog2(VM_GROWSDOWN)]   = "gd",
 623                [ilog2(VM_PFNMAP)]      = "pf",
 624                [ilog2(VM_DENYWRITE)]   = "dw",
 625                [ilog2(VM_LOCKED)]      = "lo",
 626                [ilog2(VM_IO)]          = "io",
 627                [ilog2(VM_SEQ_READ)]    = "sr",
 628                [ilog2(VM_RAND_READ)]   = "rr",
 629                [ilog2(VM_DONTCOPY)]    = "dc",
 630                [ilog2(VM_DONTEXPAND)]  = "de",
 631                [ilog2(VM_ACCOUNT)]     = "ac",
 632                [ilog2(VM_NORESERVE)]   = "nr",
 633                [ilog2(VM_HUGETLB)]     = "ht",
 634                [ilog2(VM_SYNC)]        = "sf",
 635                [ilog2(VM_ARCH_1)]      = "ar",
 636                [ilog2(VM_WIPEONFORK)]  = "wf",
 637                [ilog2(VM_DONTDUMP)]    = "dd",
 638#ifdef CONFIG_ARM64_BTI
 639                [ilog2(VM_ARM64_BTI)]   = "bt",
 640#endif
 641#ifdef CONFIG_MEM_SOFT_DIRTY
 642                [ilog2(VM_SOFTDIRTY)]   = "sd",
 643#endif
 644                [ilog2(VM_MIXEDMAP)]    = "mm",
 645                [ilog2(VM_HUGEPAGE)]    = "hg",
 646                [ilog2(VM_NOHUGEPAGE)]  = "nh",
 647                [ilog2(VM_MERGEABLE)]   = "mg",
 648                [ilog2(VM_UFFD_MISSING)]= "um",
 649                [ilog2(VM_UFFD_WP)]     = "uw",
 650#ifdef CONFIG_ARM64_MTE
 651                [ilog2(VM_MTE)]         = "mt",
 652                [ilog2(VM_MTE_ALLOWED)] = "",
 653#endif
 654#ifdef CONFIG_ARCH_HAS_PKEYS
 655                /* These come out via ProtectionKey: */
 656                [ilog2(VM_PKEY_BIT0)]   = "",
 657                [ilog2(VM_PKEY_BIT1)]   = "",
 658                [ilog2(VM_PKEY_BIT2)]   = "",
 659                [ilog2(VM_PKEY_BIT3)]   = "",
 660#if VM_PKEY_BIT4
 661                [ilog2(VM_PKEY_BIT4)]   = "",
 662#endif
 663#endif /* CONFIG_ARCH_HAS_PKEYS */
 664#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
 665                [ilog2(VM_UFFD_MINOR)]  = "ui",
 666#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
 667        };
 668        size_t i;
 669
 670        seq_puts(m, "VmFlags: ");
 671        for (i = 0; i < BITS_PER_LONG; i++) {
 672                if (!mnemonics[i][0])
 673                        continue;
 674                if (vma->vm_flags & (1UL << i)) {
 675                        seq_putc(m, mnemonics[i][0]);
 676                        seq_putc(m, mnemonics[i][1]);
 677                        seq_putc(m, ' ');
 678                }
 679        }
 680        seq_putc(m, '\n');
 681}
 682
 683#ifdef CONFIG_HUGETLB_PAGE
 684static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 685                                 unsigned long addr, unsigned long end,
 686                                 struct mm_walk *walk)
 687{
 688        struct mem_size_stats *mss = walk->private;
 689        struct vm_area_struct *vma = walk->vma;
 690        struct page *page = NULL;
 691
 692        if (pte_present(*pte)) {
 693                page = vm_normal_page(vma, addr, *pte);
 694        } else if (is_swap_pte(*pte)) {
 695                swp_entry_t swpent = pte_to_swp_entry(*pte);
 696
 697                if (is_migration_entry(swpent))
 698                        page = migration_entry_to_page(swpent);
 699                else if (is_device_private_entry(swpent))
 700                        page = device_private_entry_to_page(swpent);
 701        }
 702        if (page) {
 703                int mapcount = page_mapcount(page);
 704
 705                if (mapcount >= 2)
 706                        mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
 707                else
 708                        mss->private_hugetlb += huge_page_size(hstate_vma(vma));
 709        }
 710        return 0;
 711}
 712#else
 713#define smaps_hugetlb_range     NULL
 714#endif /* HUGETLB_PAGE */
 715
 716static const struct mm_walk_ops smaps_walk_ops = {
 717        .pmd_entry              = smaps_pte_range,
 718        .hugetlb_entry          = smaps_hugetlb_range,
 719};
 720
 721static const struct mm_walk_ops smaps_shmem_walk_ops = {
 722        .pmd_entry              = smaps_pte_range,
 723        .hugetlb_entry          = smaps_hugetlb_range,
 724        .pte_hole               = smaps_pte_hole,
 725};
 726
 727/*
 728 * Gather mem stats from @vma with the indicated beginning
 729 * address @start, and keep them in @mss.
 730 *
 731 * Use vm_start of @vma as the beginning address if @start is 0.
 732 */
 733static void smap_gather_stats(struct vm_area_struct *vma,
 734                struct mem_size_stats *mss, unsigned long start)
 735{
 736        const struct mm_walk_ops *ops = &smaps_walk_ops;
 737
 738        /* Invalid start */
 739        if (start >= vma->vm_end)
 740                return;
 741
 742#ifdef CONFIG_SHMEM
 743        /* In case of smaps_rollup, reset the value from previous vma */
 744        mss->check_shmem_swap = false;
 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                        mss->check_shmem_swap = true;
 763                        ops = &smaps_shmem_walk_ops;
 764                }
 765        }
 766#endif
 767        /* mmap_lock is held in m_start */
 768        if (!start)
 769                walk_page_vma(vma, ops, mss);
 770        else
 771                walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss);
 772}
 773
 774#define SEQ_PUT_DEC(str, val) \
 775                seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 776
 777/* Show the contents common for smaps and smaps_rollup */
 778static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
 779        bool rollup_mode)
 780{
 781        SEQ_PUT_DEC("Rss:            ", mss->resident);
 782        SEQ_PUT_DEC(" kB\nPss:            ", mss->pss >> PSS_SHIFT);
 783        if (rollup_mode) {
 784                /*
 785                 * These are meaningful only for smaps_rollup, otherwise two of
 786                 * them are zero, and the other one is the same as Pss.
 787                 */
 788                SEQ_PUT_DEC(" kB\nPss_Anon:       ",
 789                        mss->pss_anon >> PSS_SHIFT);
 790                SEQ_PUT_DEC(" kB\nPss_File:       ",
 791                        mss->pss_file >> PSS_SHIFT);
 792                SEQ_PUT_DEC(" kB\nPss_Shmem:      ",
 793                        mss->pss_shmem >> PSS_SHIFT);
 794        }
 795        SEQ_PUT_DEC(" kB\nShared_Clean:   ", mss->shared_clean);
 796        SEQ_PUT_DEC(" kB\nShared_Dirty:   ", mss->shared_dirty);
 797        SEQ_PUT_DEC(" kB\nPrivate_Clean:  ", mss->private_clean);
 798        SEQ_PUT_DEC(" kB\nPrivate_Dirty:  ", mss->private_dirty);
 799        SEQ_PUT_DEC(" kB\nReferenced:     ", mss->referenced);
 800        SEQ_PUT_DEC(" kB\nAnonymous:      ", mss->anonymous);
 801        SEQ_PUT_DEC(" kB\nLazyFree:       ", mss->lazyfree);
 802        SEQ_PUT_DEC(" kB\nAnonHugePages:  ", mss->anonymous_thp);
 803        SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
 804        SEQ_PUT_DEC(" kB\nFilePmdMapped:  ", mss->file_thp);
 805        SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
 806        seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
 807                                  mss->private_hugetlb >> 10, 7);
 808        SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 809        SEQ_PUT_DEC(" kB\nSwapPss:        ",
 810                                        mss->swap_pss >> PSS_SHIFT);
 811        SEQ_PUT_DEC(" kB\nLocked:         ",
 812                                        mss->pss_locked >> PSS_SHIFT);
 813        seq_puts(m, " kB\n");
 814}
 815
 816static int show_smap(struct seq_file *m, void *v)
 817{
 818        struct vm_area_struct *vma = v;
 819        struct mem_size_stats mss;
 820
 821        memset(&mss, 0, sizeof(mss));
 822
 823        smap_gather_stats(vma, &mss, 0);
 824
 825        show_map_vma(m, vma);
 826
 827        SEQ_PUT_DEC("Size:           ", vma->vm_end - vma->vm_start);
 828        SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
 829        SEQ_PUT_DEC(" kB\nMMUPageSize:    ", vma_mmu_pagesize(vma));
 830        seq_puts(m, " kB\n");
 831
 832        __show_smap(m, &mss, false);
 833
 834        seq_printf(m, "THPeligible:    %d\n",
 835                   transparent_hugepage_active(vma));
 836
 837        if (arch_pkeys_enabled())
 838                seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
 839        show_smap_vma_flags(m, vma);
 840
 841        return 0;
 842}
 843
 844static int show_smaps_rollup(struct seq_file *m, void *v)
 845{
 846        struct proc_maps_private *priv = m->private;
 847        struct mem_size_stats mss;
 848        struct mm_struct *mm;
 849        struct vm_area_struct *vma;
 850        unsigned long last_vma_end = 0;
 851        int ret = 0;
 852
 853        priv->task = get_proc_task(priv->inode);
 854        if (!priv->task)
 855                return -ESRCH;
 856
 857        mm = priv->mm;
 858        if (!mm || !mmget_not_zero(mm)) {
 859                ret = -ESRCH;
 860                goto out_put_task;
 861        }
 862
 863        memset(&mss, 0, sizeof(mss));
 864
 865        ret = mmap_read_lock_killable(mm);
 866        if (ret)
 867                goto out_put_mm;
 868
 869        hold_task_mempolicy(priv);
 870
 871        for (vma = priv->mm->mmap; vma;) {
 872                smap_gather_stats(vma, &mss, 0);
 873                last_vma_end = vma->vm_end;
 874
 875                /*
 876                 * Release mmap_lock temporarily if someone wants to
 877                 * access it for write request.
 878                 */
 879                if (mmap_lock_is_contended(mm)) {
 880                        mmap_read_unlock(mm);
 881                        ret = mmap_read_lock_killable(mm);
 882                        if (ret) {
 883                                release_task_mempolicy(priv);
 884                                goto out_put_mm;
 885                        }
 886
 887                        /*
 888                         * After dropping the lock, there are four cases to
 889                         * consider. See the following example for explanation.
 890                         *
 891                         *   +------+------+-----------+
 892                         *   | VMA1 | VMA2 | VMA3      |
 893                         *   +------+------+-----------+
 894                         *   |      |      |           |
 895                         *  4k     8k     16k         400k
 896                         *
 897                         * Suppose we drop the lock after reading VMA2 due to
 898                         * contention, then we get:
 899                         *
 900                         *      last_vma_end = 16k
 901                         *
 902                         * 1) VMA2 is freed, but VMA3 exists:
 903                         *
 904                         *    find_vma(mm, 16k - 1) will return VMA3.
 905                         *    In this case, just continue from VMA3.
 906                         *
 907                         * 2) VMA2 still exists:
 908                         *
 909                         *    find_vma(mm, 16k - 1) will return VMA2.
 910                         *    Iterate the loop like the original one.
 911                         *
 912                         * 3) No more VMAs can be found:
 913                         *
 914                         *    find_vma(mm, 16k - 1) will return NULL.
 915                         *    No more things to do, just break.
 916                         *
 917                         * 4) (last_vma_end - 1) is the middle of a vma (VMA'):
 918                         *
 919                         *    find_vma(mm, 16k - 1) will return VMA' whose range
 920                         *    contains last_vma_end.
 921                         *    Iterate VMA' from last_vma_end.
 922                         */
 923                        vma = find_vma(mm, last_vma_end - 1);
 924                        /* Case 3 above */
 925                        if (!vma)
 926                                break;
 927
 928                        /* Case 1 above */
 929                        if (vma->vm_start >= last_vma_end)
 930                                continue;
 931
 932                        /* Case 4 above */
 933                        if (vma->vm_end > last_vma_end)
 934                                smap_gather_stats(vma, &mss, last_vma_end);
 935                }
 936                /* Case 2 above */
 937                vma = vma->vm_next;
 938        }
 939
 940        show_vma_header_prefix(m, priv->mm->mmap->vm_start,
 941                               last_vma_end, 0, 0, 0, 0);
 942        seq_pad(m, ' ');
 943        seq_puts(m, "[rollup]\n");
 944
 945        __show_smap(m, &mss, true);
 946
 947        release_task_mempolicy(priv);
 948        mmap_read_unlock(mm);
 949
 950out_put_mm:
 951        mmput(mm);
 952out_put_task:
 953        put_task_struct(priv->task);
 954        priv->task = NULL;
 955
 956        return ret;
 957}
 958#undef SEQ_PUT_DEC
 959
 960static const struct seq_operations proc_pid_smaps_op = {
 961        .start  = m_start,
 962        .next   = m_next,
 963        .stop   = m_stop,
 964        .show   = show_smap
 965};
 966
 967static int pid_smaps_open(struct inode *inode, struct file *file)
 968{
 969        return do_maps_open(inode, file, &proc_pid_smaps_op);
 970}
 971
 972static int smaps_rollup_open(struct inode *inode, struct file *file)
 973{
 974        int ret;
 975        struct proc_maps_private *priv;
 976
 977        priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
 978        if (!priv)
 979                return -ENOMEM;
 980
 981        ret = single_open(file, show_smaps_rollup, priv);
 982        if (ret)
 983                goto out_free;
 984
 985        priv->inode = inode;
 986        priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 987        if (IS_ERR(priv->mm)) {
 988                ret = PTR_ERR(priv->mm);
 989
 990                single_release(inode, file);
 991                goto out_free;
 992        }
 993
 994        return 0;
 995
 996out_free:
 997        kfree(priv);
 998        return ret;
 999}
1000
1001static int smaps_rollup_release(struct inode *inode, struct file *file)
1002{
1003        struct seq_file *seq = file->private_data;
1004        struct proc_maps_private *priv = seq->private;
1005
1006        if (priv->mm)
1007                mmdrop(priv->mm);
1008
1009        kfree(priv);
1010        return single_release(inode, file);
1011}
1012
1013const struct file_operations proc_pid_smaps_operations = {
1014        .open           = pid_smaps_open,
1015        .read           = seq_read,
1016        .llseek         = seq_lseek,
1017        .release        = proc_map_release,
1018};
1019
1020const struct file_operations proc_pid_smaps_rollup_operations = {
1021        .open           = smaps_rollup_open,
1022        .read           = seq_read,
1023        .llseek         = seq_lseek,
1024        .release        = smaps_rollup_release,
1025};
1026
1027enum clear_refs_types {
1028        CLEAR_REFS_ALL = 1,
1029        CLEAR_REFS_ANON,
1030        CLEAR_REFS_MAPPED,
1031        CLEAR_REFS_SOFT_DIRTY,
1032        CLEAR_REFS_MM_HIWATER_RSS,
1033        CLEAR_REFS_LAST,
1034};
1035
1036struct clear_refs_private {
1037        enum clear_refs_types type;
1038};
1039
1040#ifdef CONFIG_MEM_SOFT_DIRTY
1041
1042static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1043{
1044        struct page *page;
1045
1046        if (!pte_write(pte))
1047                return false;
1048        if (!is_cow_mapping(vma->vm_flags))
1049                return false;
1050        if (likely(!atomic_read(&vma->vm_mm->has_pinned)))
1051                return false;
1052        page = vm_normal_page(vma, addr, pte);
1053        if (!page)
1054                return false;
1055        return page_maybe_dma_pinned(page);
1056}
1057
1058static inline void clear_soft_dirty(struct vm_area_struct *vma,
1059                unsigned long addr, pte_t *pte)
1060{
1061        /*
1062         * The soft-dirty tracker uses #PF-s to catch writes
1063         * to pages, so write-protect the pte as well. See the
1064         * Documentation/admin-guide/mm/soft-dirty.rst for full description
1065         * of how soft-dirty works.
1066         */
1067        pte_t ptent = *pte;
1068
1069        if (pte_present(ptent)) {
1070                pte_t old_pte;
1071
1072                if (pte_is_pinned(vma, addr, ptent))
1073                        return;
1074                old_pte = ptep_modify_prot_start(vma, addr, pte);
1075                ptent = pte_wrprotect(old_pte);
1076                ptent = pte_clear_soft_dirty(ptent);
1077                ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1078        } else if (is_swap_pte(ptent)) {
1079                ptent = pte_swp_clear_soft_dirty(ptent);
1080                set_pte_at(vma->vm_mm, addr, pte, ptent);
1081        }
1082}
1083#else
1084static inline void clear_soft_dirty(struct vm_area_struct *vma,
1085                unsigned long addr, pte_t *pte)
1086{
1087}
1088#endif
1089
1090#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1091static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1092                unsigned long addr, pmd_t *pmdp)
1093{
1094        pmd_t old, pmd = *pmdp;
1095
1096        if (pmd_present(pmd)) {
1097                /* See comment in change_huge_pmd() */
1098                old = pmdp_invalidate(vma, addr, pmdp);
1099                if (pmd_dirty(old))
1100                        pmd = pmd_mkdirty(pmd);
1101                if (pmd_young(old))
1102                        pmd = pmd_mkyoung(pmd);
1103
1104                pmd = pmd_wrprotect(pmd);
1105                pmd = pmd_clear_soft_dirty(pmd);
1106
1107                set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1108        } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1109                pmd = pmd_swp_clear_soft_dirty(pmd);
1110                set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1111        }
1112}
1113#else
1114static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1115                unsigned long addr, pmd_t *pmdp)
1116{
1117}
1118#endif
1119
1120static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1121                                unsigned long end, struct mm_walk *walk)
1122{
1123        struct clear_refs_private *cp = walk->private;
1124        struct vm_area_struct *vma = walk->vma;
1125        pte_t *pte, ptent;
1126        spinlock_t *ptl;
1127        struct page *page;
1128
1129        ptl = pmd_trans_huge_lock(pmd, vma);
1130        if (ptl) {
1131                if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1132                        clear_soft_dirty_pmd(vma, addr, pmd);
1133                        goto out;
1134                }
1135
1136                if (!pmd_present(*pmd))
1137                        goto out;
1138
1139                page = pmd_page(*pmd);
1140
1141                /* Clear accessed and referenced bits. */
1142                pmdp_test_and_clear_young(vma, addr, pmd);
1143                test_and_clear_page_young(page);
1144                ClearPageReferenced(page);
1145out:
1146                spin_unlock(ptl);
1147                return 0;
1148        }
1149
1150        if (pmd_trans_unstable(pmd))
1151                return 0;
1152
1153        pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1154        for (; addr != end; pte++, addr += PAGE_SIZE) {
1155                ptent = *pte;
1156
1157                if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1158                        clear_soft_dirty(vma, addr, pte);
1159                        continue;
1160                }
1161
1162                if (!pte_present(ptent))
1163                        continue;
1164
1165                page = vm_normal_page(vma, addr, ptent);
1166                if (!page)
1167                        continue;
1168
1169                /* Clear accessed and referenced bits. */
1170                ptep_test_and_clear_young(vma, addr, pte);
1171                test_and_clear_page_young(page);
1172                ClearPageReferenced(page);
1173        }
1174        pte_unmap_unlock(pte - 1, ptl);
1175        cond_resched();
1176        return 0;
1177}
1178
1179static int clear_refs_test_walk(unsigned long start, unsigned long end,
1180                                struct mm_walk *walk)
1181{
1182        struct clear_refs_private *cp = walk->private;
1183        struct vm_area_struct *vma = walk->vma;
1184
1185        if (vma->vm_flags & VM_PFNMAP)
1186                return 1;
1187
1188        /*
1189         * Writing 1 to /proc/pid/clear_refs affects all pages.
1190         * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1191         * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1192         * Writing 4 to /proc/pid/clear_refs affects all pages.
1193         */
1194        if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1195                return 1;
1196        if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1197                return 1;
1198        return 0;
1199}
1200
1201static const struct mm_walk_ops clear_refs_walk_ops = {
1202        .pmd_entry              = clear_refs_pte_range,
1203        .test_walk              = clear_refs_test_walk,
1204};
1205
1206static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1207                                size_t count, loff_t *ppos)
1208{
1209        struct task_struct *task;
1210        char buffer[PROC_NUMBUF];
1211        struct mm_struct *mm;
1212        struct vm_area_struct *vma;
1213        enum clear_refs_types type;
1214        int itype;
1215        int rv;
1216
1217        memset(buffer, 0, sizeof(buffer));
1218        if (count > sizeof(buffer) - 1)
1219                count = sizeof(buffer) - 1;
1220        if (copy_from_user(buffer, buf, count))
1221                return -EFAULT;
1222        rv = kstrtoint(strstrip(buffer), 10, &itype);
1223        if (rv < 0)
1224                return rv;
1225        type = (enum clear_refs_types)itype;
1226        if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1227                return -EINVAL;
1228
1229        task = get_proc_task(file_inode(file));
1230        if (!task)
1231                return -ESRCH;
1232        mm = get_task_mm(task);
1233        if (mm) {
1234                struct mmu_notifier_range range;
1235                struct clear_refs_private cp = {
1236                        .type = type,
1237                };
1238
1239                if (mmap_write_lock_killable(mm)) {
1240                        count = -EINTR;
1241                        goto out_mm;
1242                }
1243                if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1244                        /*
1245                         * Writing 5 to /proc/pid/clear_refs resets the peak
1246                         * resident set size to this mm's current rss value.
1247                         */
1248                        reset_mm_hiwater_rss(mm);
1249                        goto out_unlock;
1250                }
1251
1252                if (type == CLEAR_REFS_SOFT_DIRTY) {
1253                        for (vma = mm->mmap; vma; vma = vma->vm_next) {
1254                                if (!(vma->vm_flags & VM_SOFTDIRTY))
1255                                        continue;
1256                                vma->vm_flags &= ~VM_SOFTDIRTY;
1257                                vma_set_page_prot(vma);
1258                        }
1259
1260                        inc_tlb_flush_pending(mm);
1261                        mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1262                                                0, NULL, mm, 0, -1UL);
1263                        mmu_notifier_invalidate_range_start(&range);
1264                }
1265                walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops,
1266                                &cp);
1267                if (type == CLEAR_REFS_SOFT_DIRTY) {
1268                        mmu_notifier_invalidate_range_end(&range);
1269                        flush_tlb_mm(mm);
1270                        dec_tlb_flush_pending(mm);
1271                }
1272out_unlock:
1273                mmap_write_unlock(mm);
1274out_mm:
1275                mmput(mm);
1276        }
1277        put_task_struct(task);
1278
1279        return count;
1280}
1281
1282const struct file_operations proc_clear_refs_operations = {
1283        .write          = clear_refs_write,
1284        .llseek         = noop_llseek,
1285};
1286
1287typedef struct {
1288        u64 pme;
1289} pagemap_entry_t;
1290
1291struct pagemapread {
1292        int pos, len;           /* units: PM_ENTRY_BYTES, not bytes */
1293        pagemap_entry_t *buffer;
1294        bool show_pfn;
1295};
1296
1297#define PAGEMAP_WALK_SIZE       (PMD_SIZE)
1298#define PAGEMAP_WALK_MASK       (PMD_MASK)
1299
1300#define PM_ENTRY_BYTES          sizeof(pagemap_entry_t)
1301#define PM_PFRAME_BITS          55
1302#define PM_PFRAME_MASK          GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1303#define PM_SOFT_DIRTY           BIT_ULL(55)
1304#define PM_MMAP_EXCLUSIVE       BIT_ULL(56)
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
1311static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1312{
1313        return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1314}
1315
1316static 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
1325static 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        }
1361out:
1362        return err;
1363}
1364
1365static 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        } else if (is_swap_pte(pte)) {
1379                swp_entry_t entry;
1380                if (pte_swp_soft_dirty(pte))
1381                        flags |= PM_SOFT_DIRTY;
1382                entry = pte_to_swp_entry(pte);
1383                if (pm->show_pfn)
1384                        frame = swp_type(entry) |
1385                                (swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1386                flags |= PM_SWAP;
1387                if (is_migration_entry(entry))
1388                        page = migration_entry_to_page(entry);
1389
1390                if (is_device_private_entry(entry))
1391                        page = device_private_entry_to_page(entry);
1392        }
1393
1394        if (page && !PageAnon(page))
1395                flags |= PM_FILE;
1396        if (page && page_mapcount(page) == 1)
1397                flags |= PM_MMAP_EXCLUSIVE;
1398        if (vma->vm_flags & VM_SOFTDIRTY)
1399                flags |= PM_SOFT_DIRTY;
1400
1401        return make_pme(frame, flags);
1402}
1403
1404static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1405                             struct mm_walk *walk)
1406{
1407        struct vm_area_struct *vma = walk->vma;
1408        struct pagemapread *pm = walk->private;
1409        spinlock_t *ptl;
1410        pte_t *pte, *orig_pte;
1411        int err = 0;
1412
1413#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1414        ptl = pmd_trans_huge_lock(pmdp, vma);
1415        if (ptl) {
1416                u64 flags = 0, frame = 0;
1417                pmd_t pmd = *pmdp;
1418                struct page *page = NULL;
1419
1420                if (vma->vm_flags & VM_SOFTDIRTY)
1421                        flags |= PM_SOFT_DIRTY;
1422
1423                if (pmd_present(pmd)) {
1424                        page = pmd_page(pmd);
1425
1426                        flags |= PM_PRESENT;
1427                        if (pmd_soft_dirty(pmd))
1428                                flags |= PM_SOFT_DIRTY;
1429                        if (pm->show_pfn)
1430                                frame = pmd_pfn(pmd) +
1431                                        ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1432                }
1433#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1434                else if (is_swap_pmd(pmd)) {
1435                        swp_entry_t entry = pmd_to_swp_entry(pmd);
1436                        unsigned long offset;
1437
1438                        if (pm->show_pfn) {
1439                                offset = swp_offset(entry) +
1440                                        ((addr & ~PMD_MASK) >> PAGE_SHIFT);
1441                                frame = swp_type(entry) |
1442                                        (offset << MAX_SWAPFILES_SHIFT);
1443                        }
1444                        flags |= PM_SWAP;
1445                        if (pmd_swp_soft_dirty(pmd))
1446                                flags |= PM_SOFT_DIRTY;
1447                        VM_BUG_ON(!is_pmd_migration_entry(pmd));
1448                        page = migration_entry_to_page(entry);
1449                }
1450#endif
1451
1452                if (page && page_mapcount(page) == 1)
1453                        flags |= PM_MMAP_EXCLUSIVE;
1454
1455                for (; addr != end; addr += PAGE_SIZE) {
1456                        pagemap_entry_t pme = make_pme(frame, flags);
1457
1458                        err = add_to_pagemap(addr, &pme, pm);
1459                        if (err)
1460                                break;
1461                        if (pm->show_pfn) {
1462                                if (flags & PM_PRESENT)
1463                                        frame++;
1464                                else if (flags & PM_SWAP)
1465                                        frame += (1 << MAX_SWAPFILES_SHIFT);
1466                        }
1467                }
1468                spin_unlock(ptl);
1469                return err;
1470        }
1471
1472        if (pmd_trans_unstable(pmdp))
1473                return 0;
1474#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1475
1476        /*
1477         * We can assume that @vma always points to a valid one and @end never
1478         * goes beyond vma->vm_end.
1479         */
1480        orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1481        for (; addr < end; pte++, addr += PAGE_SIZE) {
1482                pagemap_entry_t pme;
1483
1484                pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1485                err = add_to_pagemap(addr, &pme, pm);
1486                if (err)
1487                        break;
1488        }
1489        pte_unmap_unlock(orig_pte, ptl);
1490
1491        cond_resched();
1492
1493        return err;
1494}
1495
1496#ifdef CONFIG_HUGETLB_PAGE
1497/* This function walks within one hugetlb entry in the single call */
1498static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1499                                 unsigned long addr, unsigned long end,
1500                                 struct mm_walk *walk)
1501{
1502        struct pagemapread *pm = walk->private;
1503        struct vm_area_struct *vma = walk->vma;
1504        u64 flags = 0, frame = 0;
1505        int err = 0;
1506        pte_t pte;
1507
1508        if (vma->vm_flags & VM_SOFTDIRTY)
1509                flags |= PM_SOFT_DIRTY;
1510
1511        pte = huge_ptep_get(ptep);
1512        if (pte_present(pte)) {
1513                struct page *page = pte_page(pte);
1514
1515                if (!PageAnon(page))
1516                        flags |= PM_FILE;
1517
1518                if (page_mapcount(page) == 1)
1519                        flags |= PM_MMAP_EXCLUSIVE;
1520
1521                flags |= PM_PRESENT;
1522                if (pm->show_pfn)
1523                        frame = pte_pfn(pte) +
1524                                ((addr & ~hmask) >> PAGE_SHIFT);
1525        }
1526
1527        for (; addr != end; addr += PAGE_SIZE) {
1528                pagemap_entry_t pme = make_pme(frame, flags);
1529
1530                err = add_to_pagemap(addr, &pme, pm);
1531                if (err)
1532                        return err;
1533                if (pm->show_pfn && (flags & PM_PRESENT))
1534                        frame++;
1535        }
1536
1537        cond_resched();
1538
1539        return err;
1540}
1541#else
1542#define pagemap_hugetlb_range   NULL
1543#endif /* HUGETLB_PAGE */
1544
1545static const struct mm_walk_ops pagemap_ops = {
1546        .pmd_entry      = pagemap_pmd_range,
1547        .pte_hole       = pagemap_pte_hole,
1548        .hugetlb_entry  = pagemap_hugetlb_range,
1549};
1550
1551/*
1552 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1553 *
1554 * For each page in the address space, this file contains one 64-bit entry
1555 * consisting of the following:
1556 *
1557 * Bits 0-54  page frame number (PFN) if present
1558 * Bits 0-4   swap type if swapped
1559 * Bits 5-54  swap offset if swapped
1560 * Bit  55    pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1561 * Bit  56    page exclusively mapped
1562 * Bits 57-60 zero
1563 * Bit  61    page is file-page or shared-anon
1564 * Bit  62    page swapped
1565 * Bit  63    page present
1566 *
1567 * If the page is not present but in swap, then the PFN contains an
1568 * encoding of the swap file number and the page's offset into the
1569 * swap. Unmapped pages return a null PFN. This allows determining
1570 * precisely which pages are mapped (or in swap) and comparing mapped
1571 * pages between processes.
1572 *
1573 * Efficient users of this interface will use /proc/pid/maps to
1574 * determine which areas of memory are actually mapped and llseek to
1575 * skip over unmapped regions.
1576 */
1577static ssize_t pagemap_read(struct file *file, char __user *buf,
1578                            size_t count, loff_t *ppos)
1579{
1580        struct mm_struct *mm = file->private_data;
1581        struct pagemapread pm;
1582        unsigned long src;
1583        unsigned long svpfn;
1584        unsigned long start_vaddr;
1585        unsigned long end_vaddr;
1586        int ret = 0, copied = 0;
1587
1588        if (!mm || !mmget_not_zero(mm))
1589                goto out;
1590
1591        ret = -EINVAL;
1592        /* file position must be aligned */
1593        if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1594                goto out_mm;
1595
1596        ret = 0;
1597        if (!count)
1598                goto out_mm;
1599
1600        /* do not disclose physical addresses: attack vector */
1601        pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1602
1603        pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1604        pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1605        ret = -ENOMEM;
1606        if (!pm.buffer)
1607                goto out_mm;
1608
1609        src = *ppos;
1610        svpfn = src / PM_ENTRY_BYTES;
1611        end_vaddr = mm->task_size;
1612
1613        /* watch out for wraparound */
1614        start_vaddr = end_vaddr;
1615        if (svpfn <= (ULONG_MAX >> PAGE_SHIFT))
1616                start_vaddr = untagged_addr(svpfn << PAGE_SHIFT);
1617
1618        /* Ensure the address is inside the task */
1619        if (start_vaddr > mm->task_size)
1620                start_vaddr = end_vaddr;
1621
1622        /*
1623         * The odds are that this will stop walking way
1624         * before end_vaddr, because the length of the
1625         * user buffer is tracked in "pm", and the walk
1626         * will stop when we hit the end of the buffer.
1627         */
1628        ret = 0;
1629        while (count && (start_vaddr < end_vaddr)) {
1630                int len;
1631                unsigned long end;
1632
1633                pm.pos = 0;
1634                end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1635                /* overflow ? */
1636                if (end < start_vaddr || end > end_vaddr)
1637                        end = end_vaddr;
1638                ret = mmap_read_lock_killable(mm);
1639                if (ret)
1640                        goto out_free;
1641                ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1642                mmap_read_unlock(mm);
1643                start_vaddr = end;
1644
1645                len = min(count, PM_ENTRY_BYTES * pm.pos);
1646                if (copy_to_user(buf, pm.buffer, len)) {
1647                        ret = -EFAULT;
1648                        goto out_free;
1649                }
1650                copied += len;
1651                buf += len;
1652                count -= len;
1653        }
1654        *ppos += copied;
1655        if (!ret || ret == PM_END_OF_BUFFER)
1656                ret = copied;
1657
1658out_free:
1659        kfree(pm.buffer);
1660out_mm:
1661        mmput(mm);
1662out:
1663        return ret;
1664}
1665
1666static int pagemap_open(struct inode *inode, struct file *file)
1667{
1668        struct mm_struct *mm;
1669
1670        mm = proc_mem_open(inode, PTRACE_MODE_READ);
1671        if (IS_ERR(mm))
1672                return PTR_ERR(mm);
1673        file->private_data = mm;
1674        return 0;
1675}
1676
1677static int pagemap_release(struct inode *inode, struct file *file)
1678{
1679        struct mm_struct *mm = file->private_data;
1680
1681        if (mm)
1682                mmdrop(mm);
1683        return 0;
1684}
1685
1686const struct file_operations proc_pagemap_operations = {
1687        .llseek         = mem_lseek, /* borrow this */
1688        .read           = pagemap_read,
1689        .open           = pagemap_open,
1690        .release        = pagemap_release,
1691};
1692#endif /* CONFIG_PROC_PAGE_MONITOR */
1693
1694#ifdef CONFIG_NUMA
1695
1696struct numa_maps {
1697        unsigned long pages;
1698        unsigned long anon;
1699        unsigned long active;
1700        unsigned long writeback;
1701        unsigned long mapcount_max;
1702        unsigned long dirty;
1703        unsigned long swapcache;
1704        unsigned long node[MAX_NUMNODES];
1705};
1706
1707struct numa_maps_private {
1708        struct proc_maps_private proc_maps;
1709        struct numa_maps md;
1710};
1711
1712static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1713                        unsigned long nr_pages)
1714{
1715        int count = page_mapcount(page);
1716
1717        md->pages += nr_pages;
1718        if (pte_dirty || PageDirty(page))
1719                md->dirty += nr_pages;
1720
1721        if (PageSwapCache(page))
1722                md->swapcache += nr_pages;
1723
1724        if (PageActive(page) || PageUnevictable(page))
1725                md->active += nr_pages;
1726
1727        if (PageWriteback(page))
1728                md->writeback += nr_pages;
1729
1730        if (PageAnon(page))
1731                md->anon += nr_pages;
1732
1733        if (count > md->mapcount_max)
1734                md->mapcount_max = count;
1735
1736        md->node[page_to_nid(page)] += nr_pages;
1737}
1738
1739static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1740                unsigned long addr)
1741{
1742        struct page *page;
1743        int nid;
1744
1745        if (!pte_present(pte))
1746                return NULL;
1747
1748        page = vm_normal_page(vma, addr, pte);
1749        if (!page)
1750                return NULL;
1751
1752        if (PageReserved(page))
1753                return NULL;
1754
1755        nid = page_to_nid(page);
1756        if (!node_isset(nid, node_states[N_MEMORY]))
1757                return NULL;
1758
1759        return page;
1760}
1761
1762#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1763static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1764                                              struct vm_area_struct *vma,
1765                                              unsigned long addr)
1766{
1767        struct page *page;
1768        int nid;
1769
1770        if (!pmd_present(pmd))
1771                return NULL;
1772
1773        page = vm_normal_page_pmd(vma, addr, pmd);
1774        if (!page)
1775                return NULL;
1776
1777        if (PageReserved(page))
1778                return NULL;
1779
1780        nid = page_to_nid(page);
1781        if (!node_isset(nid, node_states[N_MEMORY]))
1782                return NULL;
1783
1784        return page;
1785}
1786#endif
1787
1788static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1789                unsigned long end, struct mm_walk *walk)
1790{
1791        struct numa_maps *md = walk->private;
1792        struct vm_area_struct *vma = walk->vma;
1793        spinlock_t *ptl;
1794        pte_t *orig_pte;
1795        pte_t *pte;
1796
1797#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1798        ptl = pmd_trans_huge_lock(pmd, vma);
1799        if (ptl) {
1800                struct page *page;
1801
1802                page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1803                if (page)
1804                        gather_stats(page, md, pmd_dirty(*pmd),
1805                                     HPAGE_PMD_SIZE/PAGE_SIZE);
1806                spin_unlock(ptl);
1807                return 0;
1808        }
1809
1810        if (pmd_trans_unstable(pmd))
1811                return 0;
1812#endif
1813        orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1814        do {
1815                struct page *page = can_gather_numa_stats(*pte, vma, addr);
1816                if (!page)
1817                        continue;
1818                gather_stats(page, md, pte_dirty(*pte), 1);
1819
1820        } while (pte++, addr += PAGE_SIZE, addr != end);
1821        pte_unmap_unlock(orig_pte, ptl);
1822        cond_resched();
1823        return 0;
1824}
1825#ifdef CONFIG_HUGETLB_PAGE
1826static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1827                unsigned long addr, unsigned long end, struct mm_walk *walk)
1828{
1829        pte_t huge_pte = huge_ptep_get(pte);
1830        struct numa_maps *md;
1831        struct page *page;
1832
1833        if (!pte_present(huge_pte))
1834                return 0;
1835
1836        page = pte_page(huge_pte);
1837        if (!page)
1838                return 0;
1839
1840        md = walk->private;
1841        gather_stats(page, md, pte_dirty(huge_pte), 1);
1842        return 0;
1843}
1844
1845#else
1846static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1847                unsigned long addr, unsigned long end, struct mm_walk *walk)
1848{
1849        return 0;
1850}
1851#endif
1852
1853static const struct mm_walk_ops show_numa_ops = {
1854        .hugetlb_entry = gather_hugetlb_stats,
1855        .pmd_entry = gather_pte_stats,
1856};
1857
1858/*
1859 * Display pages allocated per node and memory policy via /proc.
1860 */
1861static int show_numa_map(struct seq_file *m, void *v)
1862{
1863        struct numa_maps_private *numa_priv = m->private;
1864        struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1865        struct vm_area_struct *vma = v;
1866        struct numa_maps *md = &numa_priv->md;
1867        struct file *file = vma->vm_file;
1868        struct mm_struct *mm = vma->vm_mm;
1869        struct mempolicy *pol;
1870        char buffer[64];
1871        int nid;
1872
1873        if (!mm)
1874                return 0;
1875
1876        /* Ensure we start with an empty set of numa_maps statistics. */
1877        memset(md, 0, sizeof(*md));
1878
1879        pol = __get_vma_policy(vma, vma->vm_start);
1880        if (pol) {
1881                mpol_to_str(buffer, sizeof(buffer), pol);
1882                mpol_cond_put(pol);
1883        } else {
1884                mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1885        }
1886
1887        seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1888
1889        if (file) {
1890                seq_puts(m, " file=");
1891                seq_file_path(m, file, "\n\t= ");
1892        } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1893                seq_puts(m, " heap");
1894        } else if (is_stack(vma)) {
1895                seq_puts(m, " stack");
1896        }
1897
1898        if (is_vm_hugetlb_page(vma))
1899                seq_puts(m, " huge");
1900
1901        /* mmap_lock is held by m_start */
1902        walk_page_vma(vma, &show_numa_ops, md);
1903
1904        if (!md->pages)
1905                goto out;
1906
1907        if (md->anon)
1908                seq_printf(m, " anon=%lu", md->anon);
1909
1910        if (md->dirty)
1911                seq_printf(m, " dirty=%lu", md->dirty);
1912
1913        if (md->pages != md->anon && md->pages != md->dirty)
1914                seq_printf(m, " mapped=%lu", md->pages);
1915
1916        if (md->mapcount_max > 1)
1917                seq_printf(m, " mapmax=%lu", md->mapcount_max);
1918
1919        if (md->swapcache)
1920                seq_printf(m, " swapcache=%lu", md->swapcache);
1921
1922        if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1923                seq_printf(m, " active=%lu", md->active);
1924
1925        if (md->writeback)
1926                seq_printf(m, " writeback=%lu", md->writeback);
1927
1928        for_each_node_state(nid, N_MEMORY)
1929                if (md->node[nid])
1930                        seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1931
1932        seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1933out:
1934        seq_putc(m, '\n');
1935        return 0;
1936}
1937
1938static const struct seq_operations proc_pid_numa_maps_op = {
1939        .start  = m_start,
1940        .next   = m_next,
1941        .stop   = m_stop,
1942        .show   = show_numa_map,
1943};
1944
1945static int pid_numa_maps_open(struct inode *inode, struct file *file)
1946{
1947        return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
1948                                sizeof(struct numa_maps_private));
1949}
1950
1951const struct file_operations proc_pid_numa_maps_operations = {
1952        .open           = pid_numa_maps_open,
1953        .read           = seq_read,
1954        .llseek         = seq_lseek,
1955        .release        = proc_map_release,
1956};
1957
1958#endif /* CONFIG_NUMA */
1959