lustre/osd-ldiskfs/osd_io.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.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/osd/osd_io.c
  37  *
  38  * body operations
  39  *
  40  * Author: Nikita Danilov <nikita@clusterfs.com>
  41  * Author: Alex Zhuravlev <bzzz@whamcloud.com>
  42  *
  43  */
  44
  45 /* LUSTRE_VERSION_CODE */
  46 #include <lustre_ver.h>
  47 /* prerequisite for linux/xattr.h */
  48 #include <linux/types.h>
  49 /* prerequisite for linux/xattr.h */
  50 #include <linux/fs.h>
  51
  52 /* ext_depth() */
  53 #include <ldiskfs/ldiskfs.h>
  54 #include <ldiskfs/ldiskfs_jbd2.h>
  55 #include <ldiskfs/ldiskfs_extents.h>
  56
  57 /*
  58  * struct OBD_{ALLOC,FREE}*()
  59  * OBD_FAIL_CHECK
  60  */
  61 #include <obd_support.h>
  62
  63 #include "osd_internal.h"
  64
  65 #ifndef HAVE_PAGE_CONSTANT
  66 #define mapping_cap_page_constant_write(mapping) 0
  67 #define SetPageConstant(page) do {} while (0)
  68 #define ClearPageConstant(page) do {} while (0)
  69 #endif
  70
  71 #ifndef HAS_GENERIC_ERROR_REMOVE_PAGE
  72 int generic_error_remove_page(struct address_space *mapping, struct page *page)
  73 {
  74         if (mapping == NULL)
  75                 return -EINVAL;
  76
  77         if (mapping != page->mapping)
  78                 return -EIO;
  79         /*
  80          * Only punch for normal data pages for now.
  81          * Handling other types like directories would need more auditing.
  82          */
  83         if (!S_ISREG(mapping->host->i_mode))
  84                 return -EIO;
  85
  86         if (page_mapped(page)) {
  87                 unmap_mapping_range(mapping,
  88                                     (loff_t)page->index << PAGE_CACHE_SHIFT,
  89                                     PAGE_CACHE_SIZE, 0);
  90         }
  91         truncate_complete_page(mapping, page);
  92         return 0;
  93 }
  94 #endif
  95
  96 static void __osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,
  97                              int rw, int line)
  98 {
  99         LASSERTF(iobuf->dr_elapsed_valid == 0,
 100                  "iobuf %p, reqs %d, rw %d, line %d\n", iobuf,
 101                  cfs_atomic_read(&iobuf->dr_numreqs), iobuf->dr_rw,
 102                  iobuf->dr_init_at);
 103
 104         cfs_waitq_init(&iobuf->dr_wait);
 105         cfs_atomic_set(&iobuf->dr_numreqs, 0);
 106         iobuf->dr_max_pages = PTLRPC_MAX_BRW_PAGES;
 107         iobuf->dr_npages = 0;
 108         iobuf->dr_error = 0;
 109         iobuf->dr_dev = d;
 110         iobuf->dr_frags = 0;
 111         iobuf->dr_elapsed = 0;
 112         /* must be counted before, so assert */
 113         iobuf->dr_rw = rw;
 114         iobuf->dr_init_at = line;
 115 }
 116 #define osd_init_iobuf(dev,iobuf,rw) __osd_init_iobuf(dev, iobuf, rw, __LINE__)
 117
 118 static void osd_iobuf_add_page(struct osd_iobuf *iobuf, struct page *page)
 119 {
 120         LASSERT(iobuf->dr_npages < iobuf->dr_max_pages);
 121         iobuf->dr_pages[iobuf->dr_npages++] = page;
 122 }
 123
 124 void osd_fini_iobuf(struct osd_device *d, struct osd_iobuf *iobuf)
 125 {
 126         int rw = iobuf->dr_rw;
 127
 128         if (iobuf->dr_elapsed_valid) {
 129                 iobuf->dr_elapsed_valid = 0;
 130                 LASSERT(iobuf->dr_dev == d);
 131                 LASSERT(iobuf->dr_frags > 0);
 132                 lprocfs_oh_tally(&d->od_brw_stats.
 133                                  hist[BRW_R_DIO_FRAGS+rw],
 134                                  iobuf->dr_frags);
 135                 lprocfs_oh_tally_log2(&d->od_brw_stats.hist[BRW_R_IO_TIME+rw],
 136                                       iobuf->dr_elapsed);
 137         }
 138 }
 139
 140 #ifdef HAVE_BIO_ENDIO_2ARG
 141 #define DIO_RETURN(a)
 142 static void dio_complete_routine(struct bio *bio, int error)
 143 #else
 144 #define DIO_RETURN(a)   return(a)
 145 static int dio_complete_routine(struct bio *bio, unsigned int done, int error)
 146 #endif
 147 {
 148         struct osd_iobuf *iobuf = bio->bi_private;
 149         struct bio_vec *bvl;
 150         int i;
 151
 152         /* CAVEAT EMPTOR: possibly in IRQ context
 153          * DO NOT record procfs stats here!!! */
 154
 155         if (unlikely(iobuf == NULL)) {
 156                 CERROR("***** bio->bi_private is NULL!  This should never "
 157                        "happen.  Normally, I would crash here, but instead I "
 158                        "will dump the bio contents to the console.  Please "
 159                        "report this to <http://jira.whamcloud.com/> , along "
 160                        "with any interesting messages leading up to this point "
 161                        "(like SCSI errors, perhaps).  Because bi_private is "
 162                        "NULL, I can't wake up the thread that initiated this "
 163                        "IO - you will probably have to reboot this node.\n");
 164                 CERROR("bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d, "
 165                        "bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, "
 166                        "bi_private: %p\n", bio->bi_next, bio->bi_flags,
 167                        bio->bi_rw, bio->bi_vcnt, bio->bi_idx, bio->bi_size,
 168                        bio->bi_end_io, cfs_atomic_read(&bio->bi_cnt),
 169                        bio->bi_private);
 170                 DIO_RETURN(0);
 171         }
 172
 173         /* the check is outside of the cycle for performance reason -bzzz */
 174         if (!test_bit(BIO_RW, &bio->bi_rw)) {
 175                 bio_for_each_segment(bvl, bio, i) {
 176                         if (likely(error == 0))
 177                                 SetPageUptodate(bvl->bv_page);
 178                         LASSERT(PageLocked(bvl->bv_page));
 179                         ClearPageConstant(bvl->bv_page);
 180                 }
 181                 cfs_atomic_dec(&iobuf->dr_dev->od_r_in_flight);
 182         } else {
 183                 struct page *p = iobuf->dr_pages[0];
 184                 if (p->mapping) {
 185                         if (mapping_cap_page_constant_write(p->mapping)) {
 186                                 bio_for_each_segment(bvl, bio, i) {
 187                                         ClearPageConstant(bvl->bv_page);
 188                                 }
 189                         }
 190                 }
 191                 cfs_atomic_dec(&iobuf->dr_dev->od_w_in_flight);
 192         }
 193
 194         /* any real error is good enough -bzzz */
 195         if (error != 0 && iobuf->dr_error == 0)
 196                 iobuf->dr_error = error;
 197
 198         /*
 199          * set dr_elapsed before dr_numreqs turns to 0, otherwise
 200          * it's possible that service thread will see dr_numreqs
 201          * is zero, but dr_elapsed is not set yet, leading to lost
 202          * data in this processing and an assertion in a subsequent
 203          * call to OSD.
 204          */
 205         if (cfs_atomic_read(&iobuf->dr_numreqs) == 1) {
 206                 iobuf->dr_elapsed = jiffies - iobuf->dr_start_time;
 207                 iobuf->dr_elapsed_valid = 1;
 208         }
 209         if (cfs_atomic_dec_and_test(&iobuf->dr_numreqs))
 210                 cfs_waitq_signal(&iobuf->dr_wait);
 211
 212         /* Completed bios used to be chained off iobuf->dr_bios and freed in
 213          * filter_clear_dreq().  It was then possible to exhaust the biovec-256
 214          * mempool when serious on-disk fragmentation was encountered,
 215          * deadlocking the OST.  The bios are now released as soon as complete
 216          * so the pool cannot be exhausted while IOs are competing. bug 10076 */
 217         bio_put(bio);
 218         DIO_RETURN(0);
 219 }
 220
 221 static void record_start_io(struct osd_iobuf *iobuf, int size)
 222 {
 223         struct osd_device    *osd = iobuf->dr_dev;
 224         struct obd_histogram *h = osd->od_brw_stats.hist;
 225
 226         iobuf->dr_frags++;
 227         cfs_atomic_inc(&iobuf->dr_numreqs);
 228
 229         if (iobuf->dr_rw == 0) {
 230                 cfs_atomic_inc(&osd->od_r_in_flight);
 231                 lprocfs_oh_tally(&h[BRW_R_RPC_HIST],
 232                                  cfs_atomic_read(&osd->od_r_in_flight));
 233                 lprocfs_oh_tally_log2(&h[BRW_R_DISK_IOSIZE], size);
 234         } else if (iobuf->dr_rw == 1) {
 235                 cfs_atomic_inc(&osd->od_w_in_flight);
 236                 lprocfs_oh_tally(&h[BRW_W_RPC_HIST],
 237                                  cfs_atomic_read(&osd->od_w_in_flight));
 238                 lprocfs_oh_tally_log2(&h[BRW_W_DISK_IOSIZE], size);
 239         } else {
 240                 LBUG();
 241         }
 242 }
 243
 244 static void osd_submit_bio(int rw, struct bio *bio)
 245 {
 246         LASSERTF(rw == 0 || rw == 1, "%x\n", rw);
 247         if (rw == 0)
 248                 submit_bio(READ, bio);
 249         else
 250                 submit_bio(WRITE, bio);
 251 }
 252
 253 static int can_be_merged(struct bio *bio, sector_t sector)
 254 {
 255         unsigned int size;
 256
 257         if (!bio)
 258                 return 0;
 259
 260         size = bio->bi_size >> 9;
 261         return bio->bi_sector + size == sector ? 1 : 0;
 262 }
 263
 264 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
 265                       struct osd_iobuf *iobuf)
 266 {
 267         int            blocks_per_page = CFS_PAGE_SIZE >> inode->i_blkbits;
 268         struct page  **pages = iobuf->dr_pages;
 269         int            npages = iobuf->dr_npages;
 270         unsigned long *blocks = iobuf->dr_blocks;
 271         int            total_blocks = npages * blocks_per_page;
 272         int            sector_bits = inode->i_sb->s_blocksize_bits - 9;
 273         unsigned int   blocksize = inode->i_sb->s_blocksize;
 274         struct bio    *bio = NULL;
 275         struct page   *page;
 276         unsigned int   page_offset;
 277         sector_t       sector;
 278         int            nblocks;
 279         int            block_idx;
 280         int            page_idx;
 281         int            i;
 282         int            rc = 0;
 283         ENTRY;
 284
 285         LASSERT(iobuf->dr_npages == npages);
 286
 287         osd_brw_stats_update(osd, iobuf);
 288         iobuf->dr_start_time = cfs_time_current();
 289
 290         for (page_idx = 0, block_idx = 0;
 291              page_idx < npages;
 292              page_idx++, block_idx += blocks_per_page) {
 293
 294                 page = pages[page_idx];
 295                 LASSERT(block_idx + blocks_per_page <= total_blocks);
 296
 297                 for (i = 0, page_offset = 0;
 298                      i < blocks_per_page;
 299                      i += nblocks, page_offset += blocksize * nblocks) {
 300
 301                         nblocks = 1;
 302
 303                         if (blocks[block_idx + i] == 0) {  /* hole */
 304                                 LASSERTF(iobuf->dr_rw == 0,
 305                                          "page_idx %u, block_idx %u, i %u\n",
 306                                          page_idx, block_idx, i);
 307                                 memset(kmap(page) + page_offset, 0, blocksize);
 308                                 kunmap(page);
 309                                 continue;
 310                         }
 311
 312                         sector = (sector_t)blocks[block_idx + i] << sector_bits;
 313
 314                         /* Additional contiguous file blocks? */
 315                         while (i + nblocks < blocks_per_page &&
 316                                (sector + (nblocks << sector_bits)) ==
 317                                ((sector_t)blocks[block_idx + i + nblocks] <<
 318                                 sector_bits))
 319                                 nblocks++;
 320
 321                         /* I only set the page to be constant only if it
 322                          * is mapped to a contiguous underlying disk block(s).
 323                          * It will then make sure the corresponding device
 324                          * cache of raid5 will be overwritten by this page.
 325                          * - jay */
 326                         if (iobuf->dr_rw && (nblocks == blocks_per_page) &&
 327                             mapping_cap_page_constant_write(inode->i_mapping))
 328                                 SetPageConstant(page);
 329
 330                         if (bio != NULL &&
 331                             can_be_merged(bio, sector) &&
 332                             bio_add_page(bio, page,
 333                                          blocksize * nblocks, page_offset) != 0)
 334                                 continue;       /* added this frag OK */
 335
 336                         if (bio != NULL) {
 337                                 struct request_queue *q =
 338                                         bdev_get_queue(bio->bi_bdev);
 339
 340                                 /* Dang! I have to fragment this I/O */
 341                                 CDEBUG(D_INODE, "bio++ sz %d vcnt %d(%d) "
 342                                        "sectors %d(%d) psg %d(%d) hsg %d(%d)\n",
 343                                        bio->bi_size,
 344                                        bio->bi_vcnt, bio->bi_max_vecs,
 345                                        bio->bi_size >> 9, queue_max_sectors(q),
 346                                        bio_phys_segments(q, bio),
 347                                        queue_max_phys_segments(q),
 348                                        bio_hw_segments(q, bio),
 349                                        queue_max_hw_segments(q));
 350
 351                                 record_start_io(iobuf, bio->bi_size);
 352                                 osd_submit_bio(iobuf->dr_rw, bio);
 353                         }
 354
 355                         /* allocate new bio */
 356                         bio = bio_alloc(GFP_NOIO, min(BIO_MAX_PAGES,
 357                                                       (npages - page_idx) *
 358                                                       blocks_per_page));
 359                         if (bio == NULL) {
 360                                 CERROR("Can't allocate bio %u*%u = %u pages\n",
 361                                        (npages - page_idx), blocks_per_page,
 362                                        (npages - page_idx) * blocks_per_page);
 363                                 rc = -ENOMEM;
 364                                 goto out;
 365                         }
 366
 367                         bio->bi_bdev = inode->i_sb->s_bdev;
 368                         bio->bi_sector = sector;
 369                         bio->bi_rw = (iobuf->dr_rw == 0) ? READ : WRITE;
 370                         bio->bi_end_io = dio_complete_routine;
 371                         bio->bi_private = iobuf;
 372
 373                         rc = bio_add_page(bio, page,
 374                                           blocksize * nblocks, page_offset);
 375                         LASSERT(rc != 0);
 376                 }
 377         }
 378
 379         if (bio != NULL) {
 380                 record_start_io(iobuf, bio->bi_size);
 381                 osd_submit_bio(iobuf->dr_rw, bio);
 382                 rc = 0;
 383         }
 384
 385  out:
 386         /* in order to achieve better IO throughput, we don't wait for writes
 387          * completion here. instead we proceed with transaction commit in
 388          * parallel and wait for IO completion once transaction is stopped
 389          * see osd_trans_stop() for more details -bzzz */
 390         if (iobuf->dr_rw == 0) {
 391                 cfs_wait_event(iobuf->dr_wait,
 392                                cfs_atomic_read(&iobuf->dr_numreqs) == 0);
 393         }
 394
 395         if (rc == 0)
 396                 rc = iobuf->dr_error;
 397         RETURN(rc);
 398 }
 399
 400 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
 401                                    struct niobuf_local *lnb)
 402 {
 403         ENTRY;
 404
 405         *nrpages = 0;
 406
 407         while (len > 0) {
 408                 int poff = offset & (CFS_PAGE_SIZE - 1);
 409                 int plen = CFS_PAGE_SIZE - poff;
 410
 411                 if (plen > len)
 412                         plen = len;
 413                 lnb->lnb_file_offset = offset;
 414                 lnb->lnb_page_offset = poff;
 415                 lnb->len = plen;
 416                 /* lb->flags = rnb->flags; */
 417                 lnb->flags = 0;
 418                 lnb->page = NULL;
 419                 lnb->rc = 0;
 420
 421                 LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
 422                          (long long) len);
 423                 offset += plen;
 424                 len -= plen;
 425                 lnb++;
 426                 (*nrpages)++;
 427         }
 428
 429         RETURN(0);
 430 }
 431
 432 struct page *osd_get_page(struct dt_object *dt, loff_t offset, int rw)
 433 {
 434         struct inode      *inode = osd_dt_obj(dt)->oo_inode;
 435         struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
 436         struct page       *page;
 437
 438         LASSERT(inode);
 439
 440         page = find_or_create_page(inode->i_mapping, offset >> CFS_PAGE_SHIFT,
 441                                    GFP_NOFS | __GFP_HIGHMEM);
 442         if (unlikely(page == NULL))
 443                 lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
 444
 445         return page;
 446 }
 447
 448 /*
 449  * there are following "locks":
 450  * journal_start
 451  * i_mutex
 452  * page lock
 453
 454  * osd write path
 455     * lock page(s)
 456     * journal_start
 457     * truncate_sem
 458
 459  * ext4 vmtruncate:
 460     * lock pages, unlock
 461     * journal_start
 462     * lock partial page
 463     * i_data_sem
 464
 465 */
 466 int osd_bufs_get(const struct lu_env *env, struct dt_object *d, loff_t pos,
 467                  ssize_t len, struct niobuf_local *lnb, int rw,
 468                  struct lustre_capa *capa)
 469 {
 470         struct osd_object   *obj    = osd_dt_obj(d);
 471         int npages, i, rc = 0;
 472
 473         LASSERT(obj->oo_inode);
 474
 475         osd_map_remote_to_local(pos, len, &npages, lnb);
 476
 477         for (i = 0; i < npages; i++, lnb++) {
 478
 479                 /* We still set up for ungranted pages so that granted pages
 480                  * can be written to disk as they were promised, and portals
 481                  * needs to keep the pages all aligned properly. */
 482                 lnb->dentry = (void *) obj;
 483
 484                 lnb->page = osd_get_page(d, lnb->lnb_file_offset, rw);
 485                 if (lnb->page == NULL)
 486                         GOTO(cleanup, rc = -ENOMEM);
 487
 488                 /* DLM locking protects us from write and truncate competing
 489                  * for same region, but truncate can leave dirty page in the
 490                  * cache. it's possible the writeout on a such a page is in
 491                  * progress when we access it. it's also possible that during
 492                  * this writeout we put new (partial) data, but then won't
 493                  * be able to proceed in filter_commitrw_write(). thus let's
 494                  * just wait for writeout completion, should be rare enough.
 495                  * -bzzz */
 496                 wait_on_page_writeback(lnb->page);
 497                 BUG_ON(PageWriteback(lnb->page));
 498
 499                 lu_object_get(&d->do_lu);
 500         }
 501         rc = i;
 502
 503 cleanup:
 504         RETURN(rc);
 505 }
 506
 507 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 508                         struct niobuf_local *lnb, int npages)
 509 {
 510         struct osd_thread_info *oti = osd_oti_get(env);
 511         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 512         struct osd_device      *d = osd_obj2dev(osd_dt_obj(dt));
 513         int                     i;
 514
 515         /* to do IO stats, notice we do this here because
 516          * osd_do_bio() doesn't wait for write to complete */
 517         osd_fini_iobuf(d, iobuf);
 518
 519         for (i = 0; i < npages; i++) {
 520                 if (lnb[i].page == NULL)
 521                         continue;
 522                 LASSERT(PageLocked(lnb[i].page));
 523                 unlock_page(lnb[i].page);
 524                 page_cache_release(lnb[i].page);
 525                 lu_object_put(env, &dt->do_lu);
 526                 lnb[i].page = NULL;
 527         }
 528         RETURN(0);
 529 }
 530
 531 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 532                           struct niobuf_local *lnb, int npages)
 533 {
 534         struct osd_thread_info *oti   = osd_oti_get(env);
 535         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 536         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
 537         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
 538         struct timeval          start;
 539         struct timeval          end;
 540         unsigned long           timediff;
 541         ssize_t                 isize;
 542         __s64                   maxidx;
 543         int                     rc = 0;
 544         int                     i;
 545         int                     cache = 0;
 546
 547         LASSERT(inode);
 548
 549         osd_init_iobuf(osd, iobuf, 0);
 550
 551         isize = i_size_read(inode);
 552         maxidx = ((isize + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT) - 1;
 553
 554         if (osd->od_writethrough_cache)
 555                 cache = 1;
 556         if (isize > osd->od_readcache_max_filesize)
 557                 cache = 0;
 558
 559         cfs_gettimeofday(&start);
 560         for (i = 0; i < npages; i++) {
 561
 562                 if (cache == 0)
 563                         generic_error_remove_page(inode->i_mapping,
 564                                                   lnb[i].page);
 565
 566                 /*
 567                  * till commit the content of the page is undefined
 568                  * we'll set it uptodate once bulk is done. otherwise
 569                  * subsequent reads can access non-stable data
 570                  */
 571                 ClearPageUptodate(lnb[i].page);
 572
 573                 if (lnb[i].len == CFS_PAGE_SIZE)
 574                         continue;
 575
 576                 if (maxidx >= lnb[i].page->index) {
 577                         osd_iobuf_add_page(iobuf, lnb[i].page);
 578                 } else {
 579                         long off;
 580                         char *p = kmap(lnb[i].page);
 581
 582                         off = lnb[i].lnb_page_offset;
 583                         if (off)
 584                                 memset(p, 0, off);
 585                         off = (lnb[i].lnb_page_offset + lnb[i].len) &
 586                               ~CFS_PAGE_MASK;
 587                         if (off)
 588                                 memset(p + off, 0, CFS_PAGE_SIZE - off);
 589                         kunmap(lnb[i].page);
 590                 }
 591         }
 592         cfs_gettimeofday(&end);
 593         timediff = cfs_timeval_sub(&end, &start, NULL);
 594         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 595
 596         if (iobuf->dr_npages) {
 597                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 598                                                        iobuf->dr_npages,
 599                                                        iobuf->dr_blocks,
 600                                                        oti->oti_created,
 601                                                        0, NULL);
 602                 if (likely(rc == 0)) {
 603                         rc = osd_do_bio(osd, inode, iobuf);
 604                         /* do IO stats for preparation reads */
 605                         osd_fini_iobuf(osd, iobuf);
 606                 }
 607         }
 608         RETURN(rc);
 609 }
 610
 611 /* Check if a block is allocated or not */
 612 static int osd_is_mapped(struct inode *inode, obd_size offset)
 613 {
 614         sector_t (*fs_bmap)(struct address_space *, sector_t);
 615
 616         fs_bmap = inode->i_mapping->a_ops->bmap;
 617
 618         /* We can't know if we are overwriting or not */
 619         if (unlikely(fs_bmap == NULL))
 620                 return 0;
 621
 622         if (i_size_read(inode) == 0)
 623                 return 0;
 624
 625         /* Beyond EOF, must not be mapped */
 626         if (((i_size_read(inode) - 1) >> inode->i_blkbits) <
 627             (offset >> inode->i_blkbits))
 628                 return 0;
 629
 630         if (fs_bmap(inode->i_mapping, offset >> inode->i_blkbits) == 0)
 631                 return 0;
 632
 633         return 1;
 634 }
 635
 636 static int osd_declare_write_commit(const struct lu_env *env,
 637                                     struct dt_object *dt,
 638                                     struct niobuf_local *lnb, int npages,
 639                                     struct thandle *handle)
 640 {
 641         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 642         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
 643         struct osd_thandle      *oh;
 644         int                      extents = 1;
 645         int                      depth;
 646         int                      i;
 647         int                      newblocks;
 648         int                      rc = 0;
 649         int                      flags = 0;
 650         bool                     ignore_quota = false;
 651         long long                quota_space = 0;
 652         ENTRY;
 653
 654         LASSERT(handle != NULL);
 655         oh = container_of0(handle, struct osd_thandle, ot_super);
 656         LASSERT(oh->ot_handle == NULL);
 657
 658         newblocks = npages;
 659
 660         /* calculate number of extents (probably better to pass nb) */
 661         for (i = 0; i < npages; i++) {
 662                 if (i && lnb[i].lnb_file_offset !=
 663                     lnb[i - 1].lnb_file_offset + lnb[i - 1].len)
 664                         extents++;
 665
 666                 if (!osd_is_mapped(inode, lnb[i].lnb_file_offset))
 667                         quota_space += CFS_PAGE_SIZE;
 668
 669                 /* ignore quota for the whole request if any page is from
 670                  * client cache or written by root.
 671                  *
 672                  * XXX we could handle this on per-lnb basis as done by
 673                  * grant. */
 674                 if ((lnb[i].flags & OBD_BRW_NOQUOTA) ||
 675                     !(lnb[i].flags & OBD_BRW_SYNC))
 676                         ignore_quota = true;
 677         }
 678
 679         /*
 680          * each extent can go into new leaf causing a split
 681          * 5 is max tree depth: inode + 4 index blocks
 682          * with blockmaps, depth is 3 at most
 683          */
 684         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
 685                 /*
 686                  * many concurrent threads may grow tree by the time
 687                  * our transaction starts. so, consider 2 is a min depth
 688                  */
 689                 depth = ext_depth(inode);
 690                 depth = max(depth, 1) + 1;
 691                 newblocks += depth;
 692                 oh->ot_credits++; /* inode */
 693                 oh->ot_credits += depth * 2 * extents;
 694         } else {
 695                 depth = 3;
 696                 newblocks += depth;
 697                 oh->ot_credits++; /* inode */
 698                 oh->ot_credits += depth * extents;
 699         }
 700
 701         /* quota space for metadata blocks */
 702         quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
 703
 704         /* quota space should be reported in 1K blocks */
 705         quota_space = toqb(quota_space);
 706
 707         /* each new block can go in different group (bitmap + gd) */
 708
 709         /* we can't dirty more bitmap blocks than exist */
 710         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
 711                 oh->ot_credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
 712         else
 713                 oh->ot_credits += newblocks;
 714
 715         /* we can't dirty more gd blocks than exist */
 716         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
 717                 oh->ot_credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
 718         else
 719                 oh->ot_credits += newblocks;
 720
 721         /* make sure the over quota flags were not set */
 722         lnb[0].flags &= ~(OBD_BRW_OVER_USRQUOTA | OBD_BRW_OVER_GRPQUOTA);
 723
 724         rc = osd_declare_inode_qid(env, inode->i_uid, inode->i_gid,
 725                                    quota_space, oh, true, true, &flags,
 726                                    ignore_quota);
 727
 728         /* we need only to store the overquota flags in the first lnb for
 729          * now, once we support multiple objects BRW, this code needs be
 730          * revised. */
 731         if (flags & QUOTA_FL_OVER_USRQUOTA)
 732                 lnb[0].flags |= OBD_BRW_OVER_USRQUOTA;
 733         if (flags & QUOTA_FL_OVER_GRPQUOTA)
 734                 lnb[0].flags |= OBD_BRW_OVER_GRPQUOTA;
 735
 736         RETURN(rc);
 737 }
 738
 739 /* Check if a block is allocated or not */
 740 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
 741                             struct niobuf_local *lnb, int npages,
 742                             struct thandle *thandle)
 743 {
 744         struct osd_thread_info *oti = osd_oti_get(env);
 745         struct osd_iobuf *iobuf = &oti->oti_iobuf;
 746         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 747         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
 748         loff_t isize;
 749         int rc = 0, i;
 750
 751         LASSERT(inode);
 752
 753         osd_init_iobuf(osd, iobuf, 1);
 754         isize = i_size_read(inode);
 755         ll_vfs_dq_init(inode);
 756
 757         for (i = 0; i < npages; i++) {
 758                 if (lnb[i].rc == -ENOSPC &&
 759                     osd_is_mapped(inode, lnb[i].lnb_file_offset)) {
 760                         /* Allow the write to proceed if overwriting an
 761                          * existing block */
 762                         lnb[i].rc = 0;
 763                 }
 764
 765                 if (lnb[i].rc) { /* ENOSPC, network RPC error, etc. */
 766                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
 767                                lnb[i].rc);
 768                         LASSERT(lnb[i].page);
 769                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 770                         continue;
 771                 }
 772
 773                 LASSERT(PageLocked(lnb[i].page));
 774                 LASSERT(!PageWriteback(lnb[i].page));
 775
 776                 if (lnb[i].lnb_file_offset + lnb[i].len > isize)
 777                         isize = lnb[i].lnb_file_offset + lnb[i].len;
 778
 779                 /*
 780                  * Since write and truncate are serialized by oo_sem, even
 781                  * partial-page truncate should not leave dirty pages in the
 782                  * page cache.
 783                  */
 784                 LASSERT(!PageDirty(lnb[i].page));
 785
 786                 SetPageUptodate(lnb[i].page);
 787
 788                 osd_iobuf_add_page(iobuf, lnb[i].page);
 789         }
 790
 791         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
 792                 rc = -ENOSPC;
 793         } else if (iobuf->dr_npages > 0) {
 794                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 795                                                        iobuf->dr_npages,
 796                                                        iobuf->dr_blocks,
 797                                                        oti->oti_created,
 798                                                        1, NULL);
 799         } else {
 800                 /* no pages to write, no transno is needed */
 801                 thandle->th_local = 1;
 802         }
 803
 804         if (likely(rc == 0)) {
 805                 if (isize > i_size_read(inode)) {
 806                         i_size_write(inode, isize);
 807                         LDISKFS_I(inode)->i_disksize = isize;
 808                         inode->i_sb->s_op->dirty_inode(inode);
 809                 }
 810
 811                 rc = osd_do_bio(osd, inode, iobuf);
 812                 /* we don't do stats here as in read path because
 813                  * write is async: we'll do this in osd_put_bufs() */
 814         }
 815
 816         if (unlikely(rc != 0)) {
 817                 /* if write fails, we should drop pages from the cache */
 818                 for (i = 0; i < npages; i++) {
 819                         if (lnb[i].page == NULL)
 820                                 continue;
 821                         LASSERT(PageLocked(lnb[i].page));
 822                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 823                 }
 824         }
 825
 826         RETURN(rc);
 827 }
 828
 829 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
 830                          struct niobuf_local *lnb, int npages)
 831 {
 832         struct osd_thread_info *oti = osd_oti_get(env);
 833         struct osd_iobuf *iobuf = &oti->oti_iobuf;
 834         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 835         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 836         struct timeval start, end;
 837         unsigned long timediff;
 838         int rc = 0, i, m = 0, cache = 0;
 839
 840         LASSERT(inode);
 841
 842         osd_init_iobuf(osd, iobuf, 0);
 843
 844         if (osd->od_read_cache)
 845                 cache = 1;
 846         if (i_size_read(inode) > osd->od_readcache_max_filesize)
 847                 cache = 0;
 848
 849         cfs_gettimeofday(&start);
 850         for (i = 0; i < npages; i++) {
 851
 852                 if (i_size_read(inode) <= lnb[i].lnb_file_offset)
 853                         /* If there's no more data, abort early.
 854                          * lnb->rc == 0, so it's easy to detect later. */
 855                         break;
 856
 857                 if (i_size_read(inode) <
 858                     lnb[i].lnb_file_offset + lnb[i].len - 1)
 859                         lnb[i].rc = i_size_read(inode) - lnb[i].lnb_file_offset;
 860                 else
 861                         lnb[i].rc = lnb[i].len;
 862                 m += lnb[i].len;
 863
 864                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS, 1);
 865                 if (PageUptodate(lnb[i].page)) {
 866                         lprocfs_counter_add(osd->od_stats,
 867                                             LPROC_OSD_CACHE_HIT, 1);
 868                 } else {
 869                         lprocfs_counter_add(osd->od_stats,
 870                                             LPROC_OSD_CACHE_MISS, 1);
 871                         osd_iobuf_add_page(iobuf, lnb[i].page);
 872                 }
 873                 if (cache == 0)
 874                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 875         }
 876         cfs_gettimeofday(&end);
 877         timediff = cfs_timeval_sub(&end, &start, NULL);
 878         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 879
 880         if (iobuf->dr_npages) {
 881                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 882                                                        iobuf->dr_npages,
 883                                                        iobuf->dr_blocks,
 884                                                        oti->oti_created,
 885                                                        0, NULL);
 886                 rc = osd_do_bio(osd, inode, iobuf);
 887
 888                 /* IO stats will be done in osd_bufs_put() */
 889         }
 890
 891         RETURN(rc);
 892 }
 893
 894 /*
 895  * XXX: Another layering violation for now.
 896  *
 897  * We don't want to use ->f_op->read methods, because generic file write
 898  *
 899  *         - serializes on ->i_sem, and
 900  *
 901  *         - does a lot of extra work like balance_dirty_pages(),
 902  *
 903  * which doesn't work for globally shared files like /last_rcvd.
 904  */
 905 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
 906 {
 907         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
 908
 909         memcpy(buffer, (char *)ei->i_data, buflen);
 910
 911         return  buflen;
 912 }
 913
 914 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
 915 {
 916         struct buffer_head *bh;
 917         unsigned long block;
 918         int osize;
 919         int blocksize;
 920         int csize;
 921         int boffs;
 922         int err;
 923
 924         /* prevent reading after eof */
 925         spin_lock(&inode->i_lock);
 926         if (i_size_read(inode) < *offs + size) {
 927                 loff_t diff = i_size_read(inode) - *offs;
 928                 spin_unlock(&inode->i_lock);
 929                 if (diff < 0) {
 930                         CDEBUG(D_EXT2, "size %llu is too short to read @%llu\n",
 931                                i_size_read(inode), *offs);
 932                         return -EBADR;
 933                 } else if (diff == 0) {
 934                         return 0;
 935                 } else {
 936                         size = diff;
 937                 }
 938         } else {
 939                 spin_unlock(&inode->i_lock);
 940         }
 941
 942         blocksize = 1 << inode->i_blkbits;
 943         osize = size;
 944         while (size > 0) {
 945                 block = *offs >> inode->i_blkbits;
 946                 boffs = *offs & (blocksize - 1);
 947                 csize = min(blocksize - boffs, size);
 948                 bh = ldiskfs_bread(NULL, inode, block, 0, &err);
 949                 if (!bh) {
 950                         CERROR("%s: can't read %u@%llu on ino %lu: rc = %d\n",
 951                                LDISKFS_SB(inode->i_sb)->s_es->s_volume_name,
 952                                csize, *offs, inode->i_ino, err);
 953                         return err;
 954                 }
 955
 956                 memcpy(buf, bh->b_data + boffs, csize);
 957                 brelse(bh);
 958
 959                 *offs += csize;
 960                 buf += csize;
 961                 size -= csize;
 962         }
 963         return osize;
 964 }
 965
 966 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
 967                         struct lu_buf *buf, loff_t *pos,
 968                         struct lustre_capa *capa)
 969 {
 970         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 971         int           rc;
 972
 973         if (osd_object_auth(env, dt, capa, CAPA_OPC_BODY_READ))
 974                 RETURN(-EACCES);
 975
 976         /* Read small symlink from inode body as we need to maintain correct
 977          * on-disk symlinks for ldiskfs.
 978          */
 979         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
 980             (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
 981                 rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
 982         else
 983                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
 984
 985         return rc;
 986 }
 987
 988 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
 989                                  const loff_t size, loff_t pos,
 990                                  struct thandle *handle)
 991 {
 992         struct osd_thandle *oh;
 993         int                 credits;
 994         struct inode       *inode;
 995         int                 rc;
 996         ENTRY;
 997
 998         LASSERT(handle != NULL);
 999
1000         oh = container_of0(handle, struct osd_thandle, ot_super);
1001         LASSERT(oh->ot_handle == NULL);
1002
1003         /* XXX: size == 0 or INT_MAX indicating a catalog header update or
1004          *      llog write, see comment in mdd_declare_llog_record().
1005          *
1006          *      This hack will be removed with llog over OSD landing
1007          */
1008         if (size == DECLARE_LLOG_REWRITE)
1009                 credits = 2;
1010         else if (size == DECLARE_LLOG_WRITE)
1011                 credits = 6;
1012         else
1013                 credits = osd_dto_credits_noquota[DTO_WRITE_BLOCK];
1014
1015         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1016
1017         inode = osd_dt_obj(dt)->oo_inode;
1018
1019         /* we may declare write to non-exist llog */
1020         if (inode == NULL)
1021                 RETURN(0);
1022
1023         /* dt_declare_write() is usually called for system objects, such
1024          * as llog or last_rcvd files. We needn't enforce quota on those
1025          * objects, so always set the lqi_space as 0. */
1026         rc = osd_declare_inode_qid(env, inode->i_uid, inode->i_gid, 0, oh,
1027                                    true, true, NULL, false);
1028         RETURN(rc);
1029 }
1030
1031 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
1032 {
1033
1034         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
1035         LDISKFS_I(inode)->i_disksize = buflen;
1036         i_size_write(inode, buflen);
1037         inode->i_sb->s_op->dirty_inode(inode);
1038
1039         return 0;
1040 }
1041
1042 int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
1043                              int write_NUL, loff_t *offs, handle_t *handle)
1044 {
1045         struct buffer_head *bh        = NULL;
1046         loff_t              offset    = *offs;
1047         loff_t              new_size  = i_size_read(inode);
1048         unsigned long       block;
1049         int                 blocksize = 1 << inode->i_blkbits;
1050         int                 err = 0;
1051         int                 size;
1052         int                 boffs;
1053         int                 dirty_inode = 0;
1054
1055         if (write_NUL) {
1056                 /*
1057                  * long symlink write does not count the NUL terminator in
1058                  * bufsize, we write it, and the inode's file size does not
1059                  * count the NUL terminator as well.
1060                  */
1061                 ((char *)buf)[bufsize] = '\0';
1062                 ++bufsize;
1063         }
1064         while (bufsize > 0) {
1065                 if (bh != NULL)
1066                         brelse(bh);
1067
1068                 block = offset >> inode->i_blkbits;
1069                 boffs = offset & (blocksize - 1);
1070                 size = min(blocksize - boffs, bufsize);
1071                 bh = ldiskfs_bread(handle, inode, block, 1, &err);
1072                 if (!bh) {
1073                         CERROR("%s: error reading offset %llu (block %lu): "
1074                                "rc = %d\n",
1075                                inode->i_sb->s_id, offset, block, err);
1076                         break;
1077                 }
1078
1079                 err = ldiskfs_journal_get_write_access(handle, bh);
1080                 if (err) {
1081                         CERROR("journal_get_write_access() returned error %d\n",
1082                                err);
1083                         break;
1084                 }
1085                 LASSERTF(boffs + size <= bh->b_size,
1086                          "boffs %d size %d bh->b_size %lu",
1087                          boffs, size, (unsigned long)bh->b_size);
1088                 memcpy(bh->b_data + boffs, buf, size);
1089                 err = ldiskfs_journal_dirty_metadata(handle, bh);
1090                 if (err)
1091                         break;
1092
1093                 if (offset + size > new_size)
1094                         new_size = offset + size;
1095                 offset += size;
1096                 bufsize -= size;
1097                 buf += size;
1098         }
1099         if (bh)
1100                 brelse(bh);
1101
1102         if (write_NUL)
1103                 --new_size;
1104         /* correct in-core and on-disk sizes */
1105         if (new_size > i_size_read(inode)) {
1106                 spin_lock(&inode->i_lock);
1107                 if (new_size > i_size_read(inode))
1108                         i_size_write(inode, new_size);
1109                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1110                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1111                         dirty_inode = 1;
1112                 }
1113                 spin_unlock(&inode->i_lock);
1114                 if (dirty_inode)
1115                         inode->i_sb->s_op->dirty_inode(inode);
1116         }
1117
1118         if (err == 0)
1119                 *offs = offset;
1120         return err;
1121 }
1122
1123 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1124                          const struct lu_buf *buf, loff_t *pos,
1125                          struct thandle *handle, struct lustre_capa *capa,
1126                          int ignore_quota)
1127 {
1128         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1129         struct osd_thandle      *oh;
1130         ssize_t                 result;
1131         int                     is_link;
1132
1133         LASSERT(dt_object_exists(dt));
1134
1135         if (osd_object_auth(env, dt, capa, CAPA_OPC_BODY_WRITE))
1136                 return -EACCES;
1137
1138         LASSERT(handle != NULL);
1139         LASSERT(inode != NULL);
1140         ll_vfs_dq_init(inode);
1141
1142         /* XXX: don't check: one declared chunk can be used many times */
1143         /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
1144
1145         oh = container_of(handle, struct osd_thandle, ot_super);
1146         LASSERT(oh->ot_handle->h_transaction != NULL);
1147         /* Write small symlink to inode body as we need to maintain correct
1148          * on-disk symlinks for ldiskfs.
1149          * Note: the buf->lb_buf contains a NUL terminator while buf->lb_len
1150          * does not count it in.
1151          */
1152         is_link = S_ISLNK(dt->do_lu.lo_header->loh_attr);
1153         if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1154                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1155         else
1156                 result = osd_ldiskfs_write_record(inode, buf->lb_buf,
1157                                                   buf->lb_len, is_link, pos,
1158                                                   oh->ot_handle);
1159         if (result == 0)
1160                 result = buf->lb_len;
1161         return result;
1162 }
1163
1164 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1165                              __u64 start, __u64 end, struct thandle *th)
1166 {
1167         struct osd_thandle *oh;
1168         struct inode       *inode;
1169         int                 rc;
1170         ENTRY;
1171
1172         LASSERT(th);
1173         oh = container_of(th, struct osd_thandle, ot_super);
1174
1175         /*
1176          * we don't need to reserve credits for whole truncate
1177          * it's not possible as truncate may need to free too many
1178          * blocks and that won't fit a single transaction. instead
1179          * we reserve credits to change i_size and put inode onto
1180          * orphan list. if needed truncate will extend or restart
1181          * transaction
1182          */
1183         osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
1184                              osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
1185
1186         inode = osd_dt_obj(dt)->oo_inode;
1187         LASSERT(inode);
1188
1189         rc = osd_declare_inode_qid(env, inode->i_uid, inode->i_gid, 0, oh,
1190                                    true, true, NULL, false);
1191         RETURN(rc);
1192 }
1193
1194 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1195                      __u64 start, __u64 end, struct thandle *th,
1196                      struct lustre_capa *capa)
1197 {
1198         struct osd_thandle *oh;
1199         struct osd_object  *obj = osd_dt_obj(dt);
1200         struct inode       *inode = obj->oo_inode;
1201         handle_t           *h;
1202         tid_t               tid;
1203         int                 rc, rc2 = 0;
1204         ENTRY;
1205
1206         LASSERT(end == OBD_OBJECT_EOF);
1207         LASSERT(dt_object_exists(dt));
1208         LASSERT(osd_invariant(obj));
1209         LASSERT(inode != NULL);
1210         ll_vfs_dq_init(inode);
1211
1212         LASSERT(th);
1213         oh = container_of(th, struct osd_thandle, ot_super);
1214         LASSERT(oh->ot_handle->h_transaction != NULL);
1215
1216         osd_trans_exec_op(env, th, OSD_OT_PUNCH);
1217
1218         tid = oh->ot_handle->h_transaction->t_tid;
1219
1220         rc = vmtruncate(inode, start);
1221
1222         /*
1223          * For a partial-page truncate, flush the page to disk immediately to
1224          * avoid data corruption during direct disk write.  b=17397
1225          */
1226         if (rc == 0 && (start & ~CFS_PAGE_MASK) != 0)
1227                 rc = filemap_fdatawrite_range(inode->i_mapping, start, start+1);
1228
1229         h = journal_current_handle();
1230         LASSERT(h != NULL);
1231         LASSERT(h == oh->ot_handle);
1232
1233         if (tid != h->h_transaction->t_tid) {
1234                 int credits = oh->ot_credits;
1235                 /*
1236                  * transaction has changed during truncate
1237                  * we need to restart the handle with our credits
1238                  */
1239                 if (h->h_buffer_credits < credits) {
1240                         if (ldiskfs_journal_extend(h, credits))
1241                                 rc2 = ldiskfs_journal_restart(h, credits);
1242                 }
1243         }
1244
1245         RETURN(rc == 0 ? rc2 : rc);
1246 }
1247
1248 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
1249                           struct ll_user_fiemap *fm)
1250 {
1251         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1252         struct osd_thread_info *info   = osd_oti_get(env);
1253         struct dentry          *dentry = &info->oti_obj_dentry;
1254         struct file            *file   = &info->oti_file;
1255         mm_segment_t            saved_fs;
1256         int rc;
1257
1258         LASSERT(inode);
1259         dentry->d_inode = inode;
1260         file->f_dentry = dentry;
1261         file->f_mapping = inode->i_mapping;
1262         file->f_op = inode->i_fop;
1263
1264         saved_fs = get_fs();
1265         set_fs(get_ds());
1266         /* ldiskfs_ioctl does not have a inode argument */
1267         if (inode->i_fop->unlocked_ioctl)
1268                 rc = inode->i_fop->unlocked_ioctl(file, FSFILT_IOC_FIEMAP,
1269                                                   (long)fm);
1270         else
1271                 rc = -ENOTTY;
1272         set_fs(saved_fs);
1273         return rc;
1274 }
1275
1276 /*
1277  * in some cases we may need declare methods for objects being created
1278  * e.g., when we create symlink
1279  */
1280 const struct dt_body_operations osd_body_ops_new = {
1281         .dbo_declare_write = osd_declare_write,
1282 };
1283
1284 const struct dt_body_operations osd_body_ops = {
1285         .dbo_read                 = osd_read,
1286         .dbo_declare_write        = osd_declare_write,
1287         .dbo_write                = osd_write,
1288         .dbo_bufs_get             = osd_bufs_get,
1289         .dbo_bufs_put             = osd_bufs_put,
1290         .dbo_write_prep           = osd_write_prep,
1291         .dbo_declare_write_commit = osd_declare_write_commit,
1292         .dbo_write_commit         = osd_write_commit,
1293         .dbo_read_prep            = osd_read_prep,
1294         .do_declare_punch         = osd_declare_punch,
1295         .do_punch                 = osd_punch,
1296         .dbo_fiemap_get           = osd_fiemap_get,
1297 };
1298