lustre/llite/llite_mmap.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2016, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  */
  31
  32 #include <linux/errno.h>
  33 #include <linux/delay.h>
  34 #include <linux/kernel.h>
  35 #include <linux/mm.h>
  36 #include <linux/file.h>
  37
  38 #define DEBUG_SUBSYSTEM S_LLITE
  39
  40 #include "llite_internal.h"
  41 #include <lustre_compat.h>
  42
  43 static const struct vm_operations_struct ll_file_vm_ops;
  44
  45 void policy_from_vma(union ldlm_policy_data *policy, struct vm_area_struct *vma,
  46                      unsigned long addr, size_t bytes)
  47 {
  48         policy->l_extent.start = ((addr - vma->vm_start) & PAGE_MASK) +
  49                                  (vma->vm_pgoff << PAGE_SHIFT);
  50         policy->l_extent.end = (policy->l_extent.start + bytes - 1) |
  51                                ~PAGE_MASK;
  52 }
  53
  54 /*
  55  * Linux commit v6.0-rc3-225-gf39af05949a4
  56  * mm: add VMA iterator
  57  */
  58 #ifndef VMA_ITERATOR
  59 #define vma_iterator vm_area_struct *
  60 #define vma_iter_init(vmip, mm, addr) *(vmip) = find_vma(mm, addr)
  61 #define for_each_vma(vmi, vma) \
  62         for (vma = vmi; vma != NULL; vma = vma->vm_next)
  63 #endif
  64
  65 struct vm_area_struct *our_vma(struct mm_struct *mm, unsigned long addr,
  66                                size_t bytes)
  67 {
  68         struct vm_area_struct *vma, *ret = NULL;
  69         struct vma_iterator vmi;
  70
  71         ENTRY;
  72
  73         /* mmap_lock must have been held by caller. */
  74         LASSERT(!mmap_write_trylock(mm));
  75
  76         vma_iter_init(&vmi, mm, addr);
  77         for_each_vma(vmi, vma) {
  78                 if (vma->vm_start < (addr + bytes))
  79                         break;
  80                 if (vma->vm_ops && vma->vm_ops == &ll_file_vm_ops &&
  81                     vma->vm_flags & VM_SHARED) {
  82                         ret = vma;
  83                         break;
  84                 }
  85         }
  86         RETURN(ret);
  87 }
  88
  89 /**
  90  * API independent part for page fault initialization.
  91  * \param env - corespondent lu_env to processing
  92  * \param vma - virtual memory area addressed to page fault
  93  * \param index - page index corespondent to fault.
  94  * \param mkwrite - whether it is mmap write.
  95  *
  96  * \return error codes from cl_io_init.
  97  */
  98 static struct cl_io *
  99 ll_fault_io_init(struct lu_env *env, struct vm_area_struct *vma,
 100                  pgoff_t index, bool mkwrite)
 101 {
 102         struct file            *file = vma->vm_file;
 103         struct inode           *inode = file_inode(file);
 104         struct cl_io           *io;
 105         struct cl_fault_io     *fio;
 106         int                     rc;
 107
 108         ENTRY;
 109
 110         if (ll_file_nolock(file))
 111                 RETURN(ERR_PTR(-EOPNOTSUPP));
 112
 113 restart:
 114         io = vvp_env_thread_io(env);
 115         io->ci_obj = ll_i2info(inode)->lli_clob;
 116         LASSERT(io->ci_obj != NULL);
 117
 118         fio = &io->u.ci_fault;
 119         fio->ft_index = index;
 120         fio->ft_executable = vma->vm_flags & VM_EXEC;
 121
 122         if (mkwrite) {
 123                 fio->ft_mkwrite = 1;
 124                 fio->ft_writable = 1;
 125         }
 126
 127         if (vma->vm_flags & VM_SEQ_READ)
 128                 io->ci_seq_read = 1;
 129         else if (vma->vm_flags & VM_RAND_READ)
 130                 io->ci_rand_read = 1;
 131
 132         rc = cl_io_init(env, io, CIT_FAULT, io->ci_obj);
 133         if (rc == 0) {
 134                 struct vvp_io *vio = vvp_env_io(env);
 135                 struct ll_file_data *fd = file->private_data;
 136
 137                 LASSERT(vio->vui_cl.cis_io == io);
 138
 139                 /* mmap lock must be MANDATORY it has to cache pages. */
 140                 io->ci_lockreq = CILR_MANDATORY;
 141                 vio->vui_fd = fd;
 142         } else {
 143                 cl_io_fini(env, io);
 144                 if (io->ci_need_restart)
 145                         goto restart;
 146
 147                 io = ERR_PTR(rc);
 148         }
 149
 150         RETURN(io);
 151 }
 152
 153 /* Sharing code of page_mkwrite method for rhel5 and rhel6 */
 154 static int ll_page_mkwrite0(struct vm_area_struct *vma, struct page *vmpage,
 155                             bool *retry)
 156 {
 157         struct lu_env           *env;
 158         struct cl_io            *io;
 159         struct vvp_io           *vio;
 160         int                      result;
 161         __u16                    refcheck;
 162         sigset_t old, new;
 163         struct inode             *inode = NULL;
 164         struct ll_inode_info     *lli;
 165
 166         ENTRY;
 167
 168         LASSERT(vmpage != NULL);
 169         env = cl_env_get(&refcheck);
 170         if (IS_ERR(env))
 171                 RETURN(PTR_ERR(env));
 172
 173         io = ll_fault_io_init(env, vma, vmpage->index, true);
 174         if (IS_ERR(io))
 175                 GOTO(out, result = PTR_ERR(io));
 176
 177         result = io->ci_result;
 178         if (result < 0)
 179                 GOTO(out_io, result);
 180
 181         vio = vvp_env_io(env);
 182         vio->u.fault.ft_vma    = vma;
 183         vio->u.fault.ft_vmpage = vmpage;
 184
 185         siginitsetinv(&new, sigmask(SIGKILL) | sigmask(SIGTERM));
 186         sigprocmask(SIG_BLOCK, &new, &old);
 187
 188         inode = vvp_object_inode(io->ci_obj);
 189         lli = ll_i2info(inode);
 190
 191         result = cl_io_loop(env, io);
 192
 193         sigprocmask(SIG_SETMASK, &old, NULL);
 194
 195         if (result == 0) {
 196                 lock_page(vmpage);
 197                 if (vmpage->mapping == NULL) {
 198                         unlock_page(vmpage);
 199
 200                         /* page was truncated and lock was cancelled, return
 201                          * ENODATA so that VM_FAULT_NOPAGE will be returned
 202                          * to handle_mm_fault().
 203                          */
 204                         if (result == 0)
 205                                 result = -ENODATA;
 206                 } else if (!PageDirty(vmpage)) {
 207                         /* race, the page has been cleaned by ptlrpcd after
 208                          * it was unlocked, it has to be added into dirty
 209                          * cache again otherwise this soon-to-dirty page won't
 210                          * consume any grants, even worse if this page is being
 211                          * transferred because it will break RPC checksum.
 212                          */
 213                         unlock_page(vmpage);
 214
 215                         CDEBUG(D_MMAP, "Race on page_mkwrite %p/%lu, page has been written out, retry.\n",
 216                                vmpage, vmpage->index);
 217
 218                         *retry = true;
 219                         result = -EAGAIN;
 220                 }
 221
 222                 if (result == 0)
 223                         set_bit(LLIF_DATA_MODIFIED, &lli->lli_flags);
 224         }
 225         EXIT;
 226
 227 out_io:
 228         cl_io_fini(env, io);
 229 out:
 230         cl_env_put(env, &refcheck);
 231         CDEBUG(D_MMAP, "%s mkwrite with %d\n", current->comm, result);
 232         LASSERT(ergo(result == 0, PageLocked(vmpage)));
 233
 234         /* if page has been unmapped, presumably due to lock reclaim for
 235          * concurrent usage, add some delay before retrying to prevent
 236          * entering live-lock situation with competitors
 237          */
 238         if (result == -ENODATA && inode != NULL) {
 239                 CDEBUG(D_MMAP, "delaying new page-fault for inode %p to prevent live-lock\n",
 240                                inode);
 241                 msleep(10);
 242         }
 243
 244         return result;
 245 }
 246
 247 static inline int to_fault_error(int result)
 248 {
 249         switch (result) {
 250         case 0:
 251                 result = VM_FAULT_LOCKED;
 252                 break;
 253         case -ENOMEM:
 254                 result = VM_FAULT_OOM;
 255                 break;
 256         default:
 257                 result = VM_FAULT_SIGBUS;
 258                 break;
 259         }
 260         return result;
 261 }
 262
 263 int ll_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 264 {
 265         struct inode *inode = file_inode(vma->vm_file);
 266         int ret;
 267         unsigned int seq;
 268
 269         /* this seqlock lets us notice if a page has been deleted on this inode
 270          * during the fault process, allowing us to catch an erroneous SIGBUS
 271          * See LU-16160
 272          */
 273         do {
 274                 seq = read_seqbegin(&ll_i2info(inode)->lli_page_inv_lock);
 275                 ret = __ll_filemap_fault(vma, vmf);
 276         } while (read_seqretry(&ll_i2info(inode)->lli_page_inv_lock, seq) &&
 277                  (ret & VM_FAULT_SIGBUS));
 278
 279         return ret;
 280 }
 281
 282 /**
 283  * Lustre implementation of a vm_operations_struct::fault() method, called by
 284  * VM to server page fault (both in kernel and user space).
 285  *
 286  * \param vma - is virtiual area struct related to page fault
 287  * \param vmf - structure which describe type and address where hit fault
 288  *
 289  * \return allocated and filled _locked_ page for address
 290  * \retval VM_FAULT_ERROR on general error
 291  * \retval NOPAGE_OOM not have memory for allocate new page
 292  */
 293 static vm_fault_t ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf)
 294 {
 295         struct inode *inode = file_inode(vma->vm_file);
 296         struct lu_env           *env;
 297         struct cl_io            *io;
 298         struct vvp_io           *vio = NULL;
 299         struct page             *vmpage;
 300         int                      result = 0;
 301         int                      fault_ret = 0;
 302         __u16                    refcheck;
 303
 304         ENTRY;
 305
 306         env = cl_env_get(&refcheck);
 307         if (IS_ERR(env))
 308                 RETURN(PTR_ERR(env));
 309
 310         if (ll_sbi_has_fast_read(ll_i2sbi(inode))) {
 311                 /* do fast fault */
 312                 bool allow_retry = vmf->flags & FAULT_FLAG_ALLOW_RETRY;
 313                 bool has_retry = vmf->flags & FAULT_FLAG_RETRY_NOWAIT;
 314
 315                 /* To avoid loops, instruct downstream to not drop mmap_sem */
 316                 /**
 317                  * only need FAULT_FLAG_ALLOW_RETRY prior to Linux 5.1
 318                  * (6b4c9f4469819), where FAULT_FLAG_RETRY_NOWAIT is enough
 319                  * to not drop mmap_sem when failed to lock the page.
 320                  */
 321                 vmf->flags |= FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_RETRY_NOWAIT;
 322                 ll_cl_add(inode, env, NULL, LCC_MMAP);
 323                 fault_ret = ll_filemap_fault(vma, vmf);
 324                 ll_cl_remove(inode, env);
 325                 if (!has_retry)
 326                         vmf->flags &= ~FAULT_FLAG_RETRY_NOWAIT;
 327                 if (!allow_retry)
 328                         vmf->flags &= ~FAULT_FLAG_ALLOW_RETRY;
 329
 330                 /* - If there is no error, then the page was found in cache and
 331                  *   uptodate;
 332                  * - If VM_FAULT_RETRY is set, the page existed but failed to
 333                  *   lock. We will try slow path to avoid loops.
 334                  * - Otherwise, it should try normal fault under DLM lock.
 335                  */
 336                 if (!(fault_ret & VM_FAULT_RETRY) &&
 337                     !(fault_ret & VM_FAULT_ERROR))
 338                         GOTO(out, result = 0);
 339
 340                 fault_ret = 0;
 341         }
 342
 343         io = ll_fault_io_init(env, vma, vmf->pgoff, false);
 344         if (IS_ERR(io))
 345                 GOTO(out, result = PTR_ERR(io));
 346
 347         result = io->ci_result;
 348         if (result == 0) {
 349                 vio = vvp_env_io(env);
 350                 vio->u.fault.ft_vma       = vma;
 351                 vio->u.fault.ft_vmpage    = NULL;
 352                 vio->u.fault.ft_vmf = vmf;
 353                 vio->u.fault.ft_flags = 0;
 354                 vio->u.fault.ft_flags_valid = 0;
 355
 356                 /* May call ll_readpage() */
 357                 ll_cl_add(inode, env, io, LCC_MMAP);
 358
 359                 result = cl_io_loop(env, io);
 360
 361                 ll_cl_remove(inode, env);
 362
 363                 /* ft_flags are only valid if we reached ll_filemap_fault() */
 364                 if (vio->u.fault.ft_flags_valid)
 365                         fault_ret = vio->u.fault.ft_flags;
 366
 367                 vmpage = vio->u.fault.ft_vmpage;
 368                 if (result != 0 && vmpage != NULL) {
 369                         put_page(vmpage);
 370                         vmf->page = NULL;
 371                 }
 372         }
 373         cl_io_fini(env, io);
 374
 375 out:
 376         cl_env_put(env, &refcheck);
 377         if (result != 0 && !(fault_ret & VM_FAULT_RETRY))
 378                 fault_ret |= to_fault_error(result);
 379
 380         CDEBUG(D_MMAP, "%s fault %d/%d\n", current->comm, fault_ret, result);
 381         RETURN(fault_ret);
 382 }
 383
 384 #ifdef HAVE_VM_OPS_USE_VM_FAULT_ONLY
 385 static vm_fault_t ll_fault(struct vm_fault *vmf)
 386 {
 387         struct vm_area_struct *vma = vmf->vma;
 388 #else
 389 static vm_fault_t ll_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 390 {
 391 #endif
 392         int count = 0;
 393         bool printed = false;
 394         bool cached;
 395         vm_fault_t result;
 396         ktime_t kstart = ktime_get();
 397         sigset_t old, new;
 398
 399         result = pcc_fault(vma, vmf, &cached);
 400         if (cached)
 401                 goto out;
 402
 403         CDEBUG(D_MMAP|D_IOTRACE,
 404                "START file %s:"DFID", vma=%p start=%#lx end=%#lx vm_flags=%#lx idx=%lu\n",
 405                file_dentry(vma->vm_file)->d_name.name,
 406                PFID(&ll_i2info(file_inode(vma->vm_file))->lli_fid),
 407                vma, vma->vm_start, vma->vm_end, vma->vm_flags, vmf->pgoff);
 408
 409         /* Only SIGKILL and SIGTERM is allowed for fault/nopage/mkwrite
 410          * so that it can be killed by admin but not cause segfault by
 411          * other signals.
 412          */
 413         siginitsetinv(&new, sigmask(SIGKILL) | sigmask(SIGTERM));
 414         sigprocmask(SIG_BLOCK, &new, &old);
 415
 416         /* make sure offset is not a negative number */
 417         if (vmf->pgoff > (MAX_LFS_FILESIZE >> PAGE_SHIFT))
 418                 return VM_FAULT_SIGBUS;
 419
 420 restart:
 421         result = ll_fault0(vma, vmf);
 422         if (vmf->page &&
 423             !(result & (VM_FAULT_RETRY | VM_FAULT_ERROR | VM_FAULT_LOCKED))) {
 424                 struct page *vmpage = vmf->page;
 425
 426                 /* lock the page, then check if this page has been truncated
 427                  * or deleted from Lustre and retry if so
 428                  */
 429                 lock_page(vmpage);
 430                 if (unlikely(vmpage->mapping == NULL) ||
 431                     vmpage->private == 0) { /* unlucky */
 432                         unlock_page(vmpage);
 433                         put_page(vmpage);
 434                         vmf->page = NULL;
 435
 436                         if (!printed && ++count > 16) {
 437                                 struct inode *inode = file_inode(vma->vm_file);
 438
 439                                 CWARN("%s: FID "DFID" under heavy mmap contention by '%s', consider revising IO pattern\n",
 440                                       ll_i2sbi(inode)->ll_fsname,
 441                                       PFID(&ll_i2info(inode)->lli_fid),
 442                                       current->comm);
 443                                 printed = true;
 444                         }
 445
 446                         goto restart;
 447                 }
 448
 449                 result |= VM_FAULT_LOCKED;
 450         }
 451         sigprocmask(SIG_SETMASK, &old, NULL);
 452
 453 out:
 454         if (vmf->page && result == VM_FAULT_LOCKED) {
 455                 ll_rw_stats_tally(ll_i2sbi(file_inode(vma->vm_file)),
 456                                   current->pid, vma->vm_file->private_data,
 457                                   vmf->page->index << PAGE_SHIFT, PAGE_SIZE,
 458                                   READ);
 459                 ll_stats_ops_tally(ll_i2sbi(file_inode(vma->vm_file)),
 460                                    LPROC_LL_FAULT,
 461                                    ktime_us_delta(ktime_get(), kstart));
 462         }
 463
 464         CDEBUG(D_IOTRACE,
 465                "COMPLETED: "DFID": vma=%p start=%#lx end=%#lx vm_flags=%#lx idx=%lu, rc %d\n",
 466                PFID(&ll_i2info(file_inode(vma->vm_file))->lli_fid),
 467                vma, vma->vm_start, vma->vm_end, vma->vm_flags, vmf->pgoff,
 468                result);
 469
 470         return result;
 471 }
 472
 473 #ifdef HAVE_VM_OPS_USE_VM_FAULT_ONLY
 474 static vm_fault_t ll_page_mkwrite(struct vm_fault *vmf)
 475 {
 476         struct vm_area_struct *vma = vmf->vma;
 477 #else
 478 static vm_fault_t ll_page_mkwrite(struct vm_area_struct *vma,
 479                                   struct vm_fault *vmf)
 480 {
 481 #endif
 482         int count = 0;
 483         bool printed = false;
 484         bool retry;
 485         bool cached;
 486         ktime_t kstart = ktime_get();
 487         vm_fault_t result;
 488
 489         CDEBUG(D_MMAP|D_IOTRACE,
 490                "START file %s:"DFID", vma=%p start=%#lx end=%#lx vm_flags=%#lx idx=%lu\n",
 491                file_dentry(vma->vm_file)->d_name.name,
 492                PFID(&ll_i2info(file_inode(vma->vm_file))->lli_fid), vma,
 493                vma->vm_start, vma->vm_end, vma->vm_flags, vmf->page->index);
 494
 495         result = pcc_page_mkwrite(vma, vmf, &cached);
 496         if (cached)
 497                 goto out;
 498
 499         file_update_time(vma->vm_file);
 500         do {
 501                 retry = false;
 502                 result = ll_page_mkwrite0(vma, vmf->page, &retry);
 503
 504                 if (!printed && ++count > 16) {
 505                         const struct dentry *de = file_dentry(vma->vm_file);
 506
 507                         CWARN("app(%s): the page %lu of file "DFID" is under heavy contention\n",
 508                               current->comm, vmf->pgoff,
 509                               PFID(ll_inode2fid(de->d_inode)));
 510                         printed = true;
 511                 }
 512         } while (retry);
 513
 514         switch (result) {
 515         case 0:
 516                 LASSERT(PageLocked(vmf->page));
 517                 result = VM_FAULT_LOCKED;
 518                 break;
 519         case -ENODATA:
 520         case -EFAULT:
 521                 result = VM_FAULT_NOPAGE;
 522                 break;
 523         case -ENOMEM:
 524                 result = VM_FAULT_OOM;
 525                 break;
 526         case -EAGAIN:
 527                 result = VM_FAULT_RETRY;
 528                 break;
 529         default:
 530                 result = VM_FAULT_SIGBUS;
 531                 break;
 532         }
 533
 534 out:
 535         if (result == VM_FAULT_LOCKED) {
 536                 ll_rw_stats_tally(ll_i2sbi(file_inode(vma->vm_file)),
 537                                   current->pid, vma->vm_file->private_data,
 538                                   vmf->page->index << PAGE_SHIFT, PAGE_SIZE,
 539                                   WRITE);
 540                 ll_stats_ops_tally(ll_i2sbi(file_inode(vma->vm_file)),
 541                                    LPROC_LL_MKWRITE,
 542                                    ktime_us_delta(ktime_get(), kstart));
 543         }
 544
 545         CDEBUG(D_IOTRACE,
 546                "COMPLETED: "DFID": vma=%p start=%#lx end=%#lx vm_flags=%#lx idx=%lu, rc %d\n",
 547                PFID(&ll_i2info(file_inode(vma->vm_file))->lli_fid),
 548                vma, vma->vm_start, vma->vm_end, vma->vm_flags,
 549                vmf->page->index, result);
 550         return result;
 551 }
 552
 553 /**
 554  *  To avoid cancel the locks covering mmapped region for lock cache pressure,
 555  *  we track the mapped vma count in vvp_object::vob_mmap_cnt.
 556  */
 557 static void ll_vm_open(struct vm_area_struct *vma)
 558 {
 559         struct inode *inode    = file_inode(vma->vm_file);
 560         struct vvp_object *vob = cl_inode2vvp(inode);
 561
 562         ENTRY;
 563         LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0);
 564         atomic_inc(&vob->vob_mmap_cnt);
 565         pcc_vm_open(vma);
 566         EXIT;
 567 }
 568
 569 /**
 570  * Dual to ll_vm_open().
 571  */
 572 static void ll_vm_close(struct vm_area_struct *vma)
 573 {
 574         struct inode      *inode = file_inode(vma->vm_file);
 575         struct vvp_object *vob   = cl_inode2vvp(inode);
 576
 577         ENTRY;
 578         atomic_dec(&vob->vob_mmap_cnt);
 579         LASSERT(atomic_read(&vob->vob_mmap_cnt) >= 0);
 580         pcc_vm_close(vma);
 581         EXIT;
 582 }
 583
 584 static const struct vm_operations_struct ll_file_vm_ops = {
 585         .fault                  = ll_fault,
 586         .page_mkwrite           = ll_page_mkwrite,
 587         .open                   = ll_vm_open,
 588         .close                  = ll_vm_close,
 589 };
 590
 591 int ll_file_mmap(struct file *file, struct vm_area_struct *vma)
 592 {
 593         struct inode *inode = file_inode(file);
 594         ktime_t kstart = ktime_get();
 595         bool cached;
 596         int rc;
 597
 598         ENTRY;
 599         CDEBUG(D_VFSTRACE | D_MMAP,
 600                "VFS_Op: fid="DFID" vma=%p start=%#lx end=%#lx vm_flags=%#lx\n",
 601                PFID(&ll_i2info(inode)->lli_fid),
 602                vma, vma->vm_start, vma->vm_end, vma->vm_flags);
 603
 604         if (ll_file_nolock(file))
 605                 RETURN(-EOPNOTSUPP);
 606
 607         rc = pcc_file_mmap(file, vma, &cached);
 608         if (cached && rc != 0)
 609                 RETURN(rc);
 610
 611         rc = generic_file_mmap(file, vma);
 612         if (rc == 0) {
 613                 vma->vm_ops = &ll_file_vm_ops;
 614                 vma->vm_ops->open(vma);
 615                 /* update the inode's size and mtime */
 616                 if (!cached)
 617                         rc = ll_glimpse_size(inode);
 618         }
 619
 620         if (!rc)
 621                 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_MMAP,
 622                                    ktime_us_delta(ktime_get(), kstart));
 623
 624         RETURN(rc);
 625 }