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 int __osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,
  97                             int rw, int line, int pages)
  98 {
  99         int blocks, i;
 100
 101         LASSERTF(iobuf->dr_elapsed_valid == 0,
 102                  "iobuf %p, reqs %d, rw %d, line %d\n", iobuf,
 103                  cfs_atomic_read(&iobuf->dr_numreqs), iobuf->dr_rw,
 104                  iobuf->dr_init_at);
 105         LASSERT(pages <= PTLRPC_MAX_BRW_PAGES);
 106
 107         cfs_waitq_init(&iobuf->dr_wait);
 108         cfs_atomic_set(&iobuf->dr_numreqs, 0);
 109         iobuf->dr_npages = 0;
 110         iobuf->dr_error = 0;
 111         iobuf->dr_dev = d;
 112         iobuf->dr_frags = 0;
 113         iobuf->dr_elapsed = 0;
 114         /* must be counted before, so assert */
 115         iobuf->dr_rw = rw;
 116         iobuf->dr_init_at = line;
 117
 118         blocks = pages * (CFS_PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
 119         if (iobuf->dr_bl_buf.lb_len >= blocks * sizeof(iobuf->dr_blocks[0])) {
 120                 LASSERT(iobuf->dr_pg_buf.lb_len >=
 121                         pages * sizeof(iobuf->dr_pages[0]));
 122                 return 0;
 123         }
 124
 125         /* start with 1MB for 4K blocks */
 126         i = 256;
 127         while (i <= PTLRPC_MAX_BRW_PAGES && i < pages)
 128                 i <<= 1;
 129
 130         CDEBUG(D_OTHER, "realloc %u for %u (%u) pages\n",
 131                (unsigned)(pages * sizeof(iobuf->dr_pages[0])), i, pages);
 132         pages = i;
 133         blocks = pages * (CFS_PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
 134         iobuf->dr_max_pages = 0;
 135         CDEBUG(D_OTHER, "realloc %u for %u blocks\n",
 136                (unsigned)(blocks * sizeof(iobuf->dr_blocks[0])), blocks);
 137
 138         lu_buf_realloc(&iobuf->dr_bl_buf, blocks * sizeof(iobuf->dr_blocks[0]));
 139         iobuf->dr_blocks = iobuf->dr_bl_buf.lb_buf;
 140         if (unlikely(iobuf->dr_blocks == NULL))
 141                 return -ENOMEM;
 142
 143         lu_buf_realloc(&iobuf->dr_pg_buf, pages * sizeof(iobuf->dr_pages[0]));
 144         iobuf->dr_pages = iobuf->dr_pg_buf.lb_buf;
 145         if (unlikely(iobuf->dr_pages == NULL))
 146                 return -ENOMEM;
 147
 148         iobuf->dr_max_pages = pages;
 149
 150         return 0;
 151 }
 152 #define osd_init_iobuf(dev, iobuf, rw, pages) \
 153         __osd_init_iobuf(dev, iobuf, rw, __LINE__, pages)
 154
 155 static void osd_iobuf_add_page(struct osd_iobuf *iobuf, struct page *page)
 156 {
 157         LASSERT(iobuf->dr_npages < iobuf->dr_max_pages);
 158         iobuf->dr_pages[iobuf->dr_npages++] = page;
 159 }
 160
 161 void osd_fini_iobuf(struct osd_device *d, struct osd_iobuf *iobuf)
 162 {
 163         int rw = iobuf->dr_rw;
 164
 165         if (iobuf->dr_elapsed_valid) {
 166                 iobuf->dr_elapsed_valid = 0;
 167                 LASSERT(iobuf->dr_dev == d);
 168                 LASSERT(iobuf->dr_frags > 0);
 169                 lprocfs_oh_tally(&d->od_brw_stats.
 170                                  hist[BRW_R_DIO_FRAGS+rw],
 171                                  iobuf->dr_frags);
 172                 lprocfs_oh_tally_log2(&d->od_brw_stats.hist[BRW_R_IO_TIME+rw],
 173                                       iobuf->dr_elapsed);
 174         }
 175 }
 176
 177 #ifndef REQ_WRITE /* pre-2.6.35 */
 178 #define __REQ_WRITE BIO_RW
 179 #endif
 180
 181 #ifdef HAVE_BIO_ENDIO_2ARG
 182 #define DIO_RETURN(a)
 183 static void dio_complete_routine(struct bio *bio, int error)
 184 #else
 185 #define DIO_RETURN(a)   return(a)
 186 static int dio_complete_routine(struct bio *bio, unsigned int done, int error)
 187 #endif
 188 {
 189         struct osd_iobuf *iobuf = bio->bi_private;
 190         struct bio_vec *bvl;
 191         int i;
 192
 193         /* CAVEAT EMPTOR: possibly in IRQ context
 194          * DO NOT record procfs stats here!!! */
 195
 196         if (unlikely(iobuf == NULL)) {
 197                 CERROR("***** bio->bi_private is NULL!  This should never "
 198                        "happen.  Normally, I would crash here, but instead I "
 199                        "will dump the bio contents to the console.  Please "
 200                        "report this to <http://jira.whamcloud.com/> , along "
 201                        "with any interesting messages leading up to this point "
 202                        "(like SCSI errors, perhaps).  Because bi_private is "
 203                        "NULL, I can't wake up the thread that initiated this "
 204                        "IO - you will probably have to reboot this node.\n");
 205                 CERROR("bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d, "
 206                        "bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, "
 207                        "bi_private: %p\n", bio->bi_next, bio->bi_flags,
 208                        bio->bi_rw, bio->bi_vcnt, bio->bi_idx, bio->bi_size,
 209                        bio->bi_end_io, cfs_atomic_read(&bio->bi_cnt),
 210                        bio->bi_private);
 211                 DIO_RETURN(0);
 212         }
 213
 214         /* the check is outside of the cycle for performance reason -bzzz */
 215         if (!test_bit(__REQ_WRITE, &bio->bi_rw)) {
 216                 bio_for_each_segment(bvl, bio, i) {
 217                         if (likely(error == 0))
 218                                 SetPageUptodate(bvl->bv_page);
 219                         LASSERT(PageLocked(bvl->bv_page));
 220                         ClearPageConstant(bvl->bv_page);
 221                 }
 222                 cfs_atomic_dec(&iobuf->dr_dev->od_r_in_flight);
 223         } else {
 224                 struct page *p = iobuf->dr_pages[0];
 225                 if (p->mapping) {
 226                         if (mapping_cap_page_constant_write(p->mapping)) {
 227                                 bio_for_each_segment(bvl, bio, i) {
 228                                         ClearPageConstant(bvl->bv_page);
 229                                 }
 230                         }
 231                 }
 232                 cfs_atomic_dec(&iobuf->dr_dev->od_w_in_flight);
 233         }
 234
 235         /* any real error is good enough -bzzz */
 236         if (error != 0 && iobuf->dr_error == 0)
 237                 iobuf->dr_error = error;
 238
 239         /*
 240          * set dr_elapsed before dr_numreqs turns to 0, otherwise
 241          * it's possible that service thread will see dr_numreqs
 242          * is zero, but dr_elapsed is not set yet, leading to lost
 243          * data in this processing and an assertion in a subsequent
 244          * call to OSD.
 245          */
 246         if (cfs_atomic_read(&iobuf->dr_numreqs) == 1) {
 247                 iobuf->dr_elapsed = jiffies - iobuf->dr_start_time;
 248                 iobuf->dr_elapsed_valid = 1;
 249         }
 250         if (cfs_atomic_dec_and_test(&iobuf->dr_numreqs))
 251                 cfs_waitq_signal(&iobuf->dr_wait);
 252
 253         /* Completed bios used to be chained off iobuf->dr_bios and freed in
 254          * filter_clear_dreq().  It was then possible to exhaust the biovec-256
 255          * mempool when serious on-disk fragmentation was encountered,
 256          * deadlocking the OST.  The bios are now released as soon as complete
 257          * so the pool cannot be exhausted while IOs are competing. bug 10076 */
 258         bio_put(bio);
 259         DIO_RETURN(0);
 260 }
 261
 262 static void record_start_io(struct osd_iobuf *iobuf, int size)
 263 {
 264         struct osd_device    *osd = iobuf->dr_dev;
 265         struct obd_histogram *h = osd->od_brw_stats.hist;
 266
 267         iobuf->dr_frags++;
 268         cfs_atomic_inc(&iobuf->dr_numreqs);
 269
 270         if (iobuf->dr_rw == 0) {
 271                 cfs_atomic_inc(&osd->od_r_in_flight);
 272                 lprocfs_oh_tally(&h[BRW_R_RPC_HIST],
 273                                  cfs_atomic_read(&osd->od_r_in_flight));
 274                 lprocfs_oh_tally_log2(&h[BRW_R_DISK_IOSIZE], size);
 275         } else if (iobuf->dr_rw == 1) {
 276                 cfs_atomic_inc(&osd->od_w_in_flight);
 277                 lprocfs_oh_tally(&h[BRW_W_RPC_HIST],
 278                                  cfs_atomic_read(&osd->od_w_in_flight));
 279                 lprocfs_oh_tally_log2(&h[BRW_W_DISK_IOSIZE], size);
 280         } else {
 281                 LBUG();
 282         }
 283 }
 284
 285 static void osd_submit_bio(int rw, struct bio *bio)
 286 {
 287         LASSERTF(rw == 0 || rw == 1, "%x\n", rw);
 288         if (rw == 0)
 289                 submit_bio(READ, bio);
 290         else
 291                 submit_bio(WRITE, bio);
 292 }
 293
 294 static int can_be_merged(struct bio *bio, sector_t sector)
 295 {
 296         unsigned int size;
 297
 298         if (!bio)
 299                 return 0;
 300
 301         size = bio->bi_size >> 9;
 302         return bio->bi_sector + size == sector ? 1 : 0;
 303 }
 304
 305 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
 306                       struct osd_iobuf *iobuf)
 307 {
 308         int            blocks_per_page = CFS_PAGE_SIZE >> inode->i_blkbits;
 309         struct page  **pages = iobuf->dr_pages;
 310         int            npages = iobuf->dr_npages;
 311         unsigned long *blocks = iobuf->dr_blocks;
 312         int            total_blocks = npages * blocks_per_page;
 313         int            sector_bits = inode->i_sb->s_blocksize_bits - 9;
 314         unsigned int   blocksize = inode->i_sb->s_blocksize;
 315         struct bio    *bio = NULL;
 316         struct page   *page;
 317         unsigned int   page_offset;
 318         sector_t       sector;
 319         int            nblocks;
 320         int            block_idx;
 321         int            page_idx;
 322         int            i;
 323         int            rc = 0;
 324         ENTRY;
 325
 326         LASSERT(iobuf->dr_npages == npages);
 327
 328         osd_brw_stats_update(osd, iobuf);
 329         iobuf->dr_start_time = cfs_time_current();
 330
 331         for (page_idx = 0, block_idx = 0;
 332              page_idx < npages;
 333              page_idx++, block_idx += blocks_per_page) {
 334
 335                 page = pages[page_idx];
 336                 LASSERT(block_idx + blocks_per_page <= total_blocks);
 337
 338                 for (i = 0, page_offset = 0;
 339                      i < blocks_per_page;
 340                      i += nblocks, page_offset += blocksize * nblocks) {
 341
 342                         nblocks = 1;
 343
 344                         if (blocks[block_idx + i] == 0) {  /* hole */
 345                                 LASSERTF(iobuf->dr_rw == 0,
 346                                          "page_idx %u, block_idx %u, i %u\n",
 347                                          page_idx, block_idx, i);
 348                                 memset(kmap(page) + page_offset, 0, blocksize);
 349                                 kunmap(page);
 350                                 continue;
 351                         }
 352
 353                         sector = (sector_t)blocks[block_idx + i] << sector_bits;
 354
 355                         /* Additional contiguous file blocks? */
 356                         while (i + nblocks < blocks_per_page &&
 357                                (sector + (nblocks << sector_bits)) ==
 358                                ((sector_t)blocks[block_idx + i + nblocks] <<
 359                                 sector_bits))
 360                                 nblocks++;
 361
 362                         /* I only set the page to be constant only if it
 363                          * is mapped to a contiguous underlying disk block(s).
 364                          * It will then make sure the corresponding device
 365                          * cache of raid5 will be overwritten by this page.
 366                          * - jay */
 367                         if (iobuf->dr_rw && (nblocks == blocks_per_page) &&
 368                             mapping_cap_page_constant_write(inode->i_mapping))
 369                                 SetPageConstant(page);
 370
 371                         if (bio != NULL &&
 372                             can_be_merged(bio, sector) &&
 373                             bio_add_page(bio, page,
 374                                          blocksize * nblocks, page_offset) != 0)
 375                                 continue;       /* added this frag OK */
 376
 377                         if (bio != NULL) {
 378                                 struct request_queue *q =
 379                                         bdev_get_queue(bio->bi_bdev);
 380
 381                                 /* Dang! I have to fragment this I/O */
 382                                 CDEBUG(D_INODE, "bio++ sz %d vcnt %d(%d) "
 383                                        "sectors %d(%d) psg %d(%d) hsg %d(%d)\n",
 384                                        bio->bi_size,
 385                                        bio->bi_vcnt, bio->bi_max_vecs,
 386                                        bio->bi_size >> 9, queue_max_sectors(q),
 387                                        bio_phys_segments(q, bio),
 388                                        queue_max_phys_segments(q),
 389                                        bio_hw_segments(q, bio),
 390                                        queue_max_hw_segments(q));
 391
 392                                 record_start_io(iobuf, bio->bi_size);
 393                                 osd_submit_bio(iobuf->dr_rw, bio);
 394                         }
 395
 396                         /* allocate new bio */
 397                         bio = bio_alloc(GFP_NOIO, min(BIO_MAX_PAGES,
 398                                                       (npages - page_idx) *
 399                                                       blocks_per_page));
 400                         if (bio == NULL) {
 401                                 CERROR("Can't allocate bio %u*%u = %u pages\n",
 402                                        (npages - page_idx), blocks_per_page,
 403                                        (npages - page_idx) * blocks_per_page);
 404                                 rc = -ENOMEM;
 405                                 goto out;
 406                         }
 407
 408                         bio->bi_bdev = inode->i_sb->s_bdev;
 409                         bio->bi_sector = sector;
 410                         bio->bi_rw = (iobuf->dr_rw == 0) ? READ : WRITE;
 411                         bio->bi_end_io = dio_complete_routine;
 412                         bio->bi_private = iobuf;
 413
 414                         rc = bio_add_page(bio, page,
 415                                           blocksize * nblocks, page_offset);
 416                         LASSERT(rc != 0);
 417                 }
 418         }
 419
 420         if (bio != NULL) {
 421                 record_start_io(iobuf, bio->bi_size);
 422                 osd_submit_bio(iobuf->dr_rw, bio);
 423                 rc = 0;
 424         }
 425
 426  out:
 427         /* in order to achieve better IO throughput, we don't wait for writes
 428          * completion here. instead we proceed with transaction commit in
 429          * parallel and wait for IO completion once transaction is stopped
 430          * see osd_trans_stop() for more details -bzzz */
 431         if (iobuf->dr_rw == 0) {
 432                 cfs_wait_event(iobuf->dr_wait,
 433                                cfs_atomic_read(&iobuf->dr_numreqs) == 0);
 434         }
 435
 436         if (rc == 0)
 437                 rc = iobuf->dr_error;
 438         RETURN(rc);
 439 }
 440
 441 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
 442                                    struct niobuf_local *lnb)
 443 {
 444         ENTRY;
 445
 446         *nrpages = 0;
 447
 448         while (len > 0) {
 449                 int poff = offset & (CFS_PAGE_SIZE - 1);
 450                 int plen = CFS_PAGE_SIZE - poff;
 451
 452                 if (plen > len)
 453                         plen = len;
 454                 lnb->lnb_file_offset = offset;
 455                 lnb->lnb_page_offset = poff;
 456                 lnb->len = plen;
 457                 /* lb->flags = rnb->flags; */
 458                 lnb->flags = 0;
 459                 lnb->page = NULL;
 460                 lnb->rc = 0;
 461
 462                 LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
 463                          (long long) len);
 464                 offset += plen;
 465                 len -= plen;
 466                 lnb++;
 467                 (*nrpages)++;
 468         }
 469
 470         RETURN(0);
 471 }
 472
 473 struct page *osd_get_page(struct dt_object *dt, loff_t offset, int rw)
 474 {
 475         struct inode      *inode = osd_dt_obj(dt)->oo_inode;
 476         struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
 477         struct page       *page;
 478
 479         LASSERT(inode);
 480
 481         page = find_or_create_page(inode->i_mapping, offset >> CFS_PAGE_SHIFT,
 482                                    GFP_NOFS | __GFP_HIGHMEM);
 483         if (unlikely(page == NULL))
 484                 lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
 485
 486         return page;
 487 }
 488
 489 /*
 490  * there are following "locks":
 491  * journal_start
 492  * i_mutex
 493  * page lock
 494
 495  * osd write path
 496     * lock page(s)
 497     * journal_start
 498     * truncate_sem
 499
 500  * ext4 vmtruncate:
 501     * lock pages, unlock
 502     * journal_start
 503     * lock partial page
 504     * i_data_sem
 505
 506 */
 507 int osd_bufs_get(const struct lu_env *env, struct dt_object *d, loff_t pos,
 508                  ssize_t len, struct niobuf_local *lnb, int rw,
 509                  struct lustre_capa *capa)
 510 {
 511         struct osd_object   *obj    = osd_dt_obj(d);
 512         int npages, i, rc = 0;
 513
 514         LASSERT(obj->oo_inode);
 515
 516         osd_map_remote_to_local(pos, len, &npages, lnb);
 517
 518         for (i = 0; i < npages; i++, lnb++) {
 519
 520                 /* We still set up for ungranted pages so that granted pages
 521                  * can be written to disk as they were promised, and portals
 522                  * needs to keep the pages all aligned properly. */
 523                 lnb->dentry = (void *) obj;
 524
 525                 lnb->page = osd_get_page(d, lnb->lnb_file_offset, rw);
 526                 if (lnb->page == NULL)
 527                         GOTO(cleanup, rc = -ENOMEM);
 528
 529                 /* DLM locking protects us from write and truncate competing
 530                  * for same region, but truncate can leave dirty page in the
 531                  * cache. it's possible the writeout on a such a page is in
 532                  * progress when we access it. it's also possible that during
 533                  * this writeout we put new (partial) data, but then won't
 534                  * be able to proceed in filter_commitrw_write(). thus let's
 535                  * just wait for writeout completion, should be rare enough.
 536                  * -bzzz */
 537                 wait_on_page_writeback(lnb->page);
 538                 BUG_ON(PageWriteback(lnb->page));
 539
 540                 lu_object_get(&d->do_lu);
 541         }
 542         rc = i;
 543
 544 cleanup:
 545         RETURN(rc);
 546 }
 547
 548 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 549                         struct niobuf_local *lnb, int npages)
 550 {
 551         struct osd_thread_info *oti = osd_oti_get(env);
 552         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 553         struct osd_device      *d = osd_obj2dev(osd_dt_obj(dt));
 554         int                     i;
 555
 556         /* to do IO stats, notice we do this here because
 557          * osd_do_bio() doesn't wait for write to complete */
 558         osd_fini_iobuf(d, iobuf);
 559
 560         for (i = 0; i < npages; i++) {
 561                 if (lnb[i].page == NULL)
 562                         continue;
 563                 LASSERT(PageLocked(lnb[i].page));
 564                 unlock_page(lnb[i].page);
 565                 page_cache_release(lnb[i].page);
 566                 lu_object_put(env, &dt->do_lu);
 567                 lnb[i].page = NULL;
 568         }
 569         RETURN(0);
 570 }
 571
 572 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 573                           struct niobuf_local *lnb, int npages)
 574 {
 575         struct osd_thread_info *oti   = osd_oti_get(env);
 576         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 577         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
 578         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
 579         struct timeval          start;
 580         struct timeval          end;
 581         unsigned long           timediff;
 582         ssize_t                 isize;
 583         __s64                   maxidx;
 584         int                     rc = 0;
 585         int                     i;
 586         int                     cache = 0;
 587
 588         LASSERT(inode);
 589
 590         rc = osd_init_iobuf(osd, iobuf, 0, npages);
 591         if (unlikely(rc != 0))
 592                 RETURN(rc);
 593
 594         isize = i_size_read(inode);
 595         maxidx = ((isize + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT) - 1;
 596
 597         if (osd->od_writethrough_cache)
 598                 cache = 1;
 599         if (isize > osd->od_readcache_max_filesize)
 600                 cache = 0;
 601
 602         cfs_gettimeofday(&start);
 603         for (i = 0; i < npages; i++) {
 604
 605                 if (cache == 0)
 606                         generic_error_remove_page(inode->i_mapping,
 607                                                   lnb[i].page);
 608
 609                 /*
 610                  * till commit the content of the page is undefined
 611                  * we'll set it uptodate once bulk is done. otherwise
 612                  * subsequent reads can access non-stable data
 613                  */
 614                 ClearPageUptodate(lnb[i].page);
 615
 616                 if (lnb[i].len == CFS_PAGE_SIZE)
 617                         continue;
 618
 619                 if (maxidx >= lnb[i].page->index) {
 620                         osd_iobuf_add_page(iobuf, lnb[i].page);
 621                 } else {
 622                         long off;
 623                         char *p = kmap(lnb[i].page);
 624
 625                         off = lnb[i].lnb_page_offset;
 626                         if (off)
 627                                 memset(p, 0, off);
 628                         off = (lnb[i].lnb_page_offset + lnb[i].len) &
 629                               ~CFS_PAGE_MASK;
 630                         if (off)
 631                                 memset(p + off, 0, CFS_PAGE_SIZE - off);
 632                         kunmap(lnb[i].page);
 633                 }
 634         }
 635         cfs_gettimeofday(&end);
 636         timediff = cfs_timeval_sub(&end, &start, NULL);
 637         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 638
 639         if (iobuf->dr_npages) {
 640                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 641                                                        iobuf->dr_npages,
 642                                                        iobuf->dr_blocks,
 643                                                        0, NULL);
 644                 if (likely(rc == 0)) {
 645                         rc = osd_do_bio(osd, inode, iobuf);
 646                         /* do IO stats for preparation reads */
 647                         osd_fini_iobuf(osd, iobuf);
 648                 }
 649         }
 650         RETURN(rc);
 651 }
 652
 653 /* Check if a block is allocated or not */
 654 static int osd_is_mapped(struct inode *inode, obd_size offset)
 655 {
 656         sector_t (*fs_bmap)(struct address_space *, sector_t);
 657
 658         fs_bmap = inode->i_mapping->a_ops->bmap;
 659
 660         /* We can't know if we are overwriting or not */
 661         if (unlikely(fs_bmap == NULL))
 662                 return 0;
 663
 664         if (i_size_read(inode) == 0)
 665                 return 0;
 666
 667         /* Beyond EOF, must not be mapped */
 668         if (((i_size_read(inode) - 1) >> inode->i_blkbits) <
 669             (offset >> inode->i_blkbits))
 670                 return 0;
 671
 672         if (fs_bmap(inode->i_mapping, offset >> inode->i_blkbits) == 0)
 673                 return 0;
 674
 675         return 1;
 676 }
 677
 678 static int osd_declare_write_commit(const struct lu_env *env,
 679                                     struct dt_object *dt,
 680                                     struct niobuf_local *lnb, int npages,
 681                                     struct thandle *handle)
 682 {
 683         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 684         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
 685         struct osd_thandle      *oh;
 686         int                      extents = 1;
 687         int                      depth;
 688         int                      i;
 689         int                      newblocks;
 690         int                      rc = 0;
 691         int                      flags = 0;
 692         bool                     ignore_quota = false;
 693         long long                quota_space = 0;
 694         ENTRY;
 695
 696         LASSERT(handle != NULL);
 697         oh = container_of0(handle, struct osd_thandle, ot_super);
 698         LASSERT(oh->ot_handle == NULL);
 699
 700         newblocks = npages;
 701
 702         /* calculate number of extents (probably better to pass nb) */
 703         for (i = 0; i < npages; i++) {
 704                 if (i && lnb[i].lnb_file_offset !=
 705                     lnb[i - 1].lnb_file_offset + lnb[i - 1].len)
 706                         extents++;
 707
 708                 if (!osd_is_mapped(inode, lnb[i].lnb_file_offset))
 709                         quota_space += CFS_PAGE_SIZE;
 710
 711                 /* ignore quota for the whole request if any page is from
 712                  * client cache or written by root.
 713                  *
 714                  * XXX we could handle this on per-lnb basis as done by
 715                  * grant. */
 716                 if ((lnb[i].flags & OBD_BRW_NOQUOTA) ||
 717                     !(lnb[i].flags & OBD_BRW_SYNC))
 718                         ignore_quota = true;
 719         }
 720
 721         /*
 722          * each extent can go into new leaf causing a split
 723          * 5 is max tree depth: inode + 4 index blocks
 724          * with blockmaps, depth is 3 at most
 725          */
 726         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
 727                 /*
 728                  * many concurrent threads may grow tree by the time
 729                  * our transaction starts. so, consider 2 is a min depth
 730                  */
 731                 depth = ext_depth(inode);
 732                 depth = max(depth, 1) + 1;
 733                 newblocks += depth;
 734                 oh->ot_credits++; /* inode */
 735                 oh->ot_credits += depth * 2 * extents;
 736         } else {
 737                 depth = 3;
 738                 newblocks += depth;
 739                 oh->ot_credits++; /* inode */
 740                 oh->ot_credits += depth * extents;
 741         }
 742
 743         /* quota space for metadata blocks */
 744         quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
 745
 746         /* quota space should be reported in 1K blocks */
 747         quota_space = toqb(quota_space);
 748
 749         /* each new block can go in different group (bitmap + gd) */
 750
 751         /* we can't dirty more bitmap blocks than exist */
 752         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
 753                 oh->ot_credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
 754         else
 755                 oh->ot_credits += newblocks;
 756
 757         /* we can't dirty more gd blocks than exist */
 758         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
 759                 oh->ot_credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
 760         else
 761                 oh->ot_credits += newblocks;
 762
 763         /* make sure the over quota flags were not set */
 764         lnb[0].flags &= ~(OBD_BRW_OVER_USRQUOTA | OBD_BRW_OVER_GRPQUOTA);
 765
 766         rc = osd_declare_inode_qid(env, inode->i_uid, inode->i_gid,
 767                                    quota_space, oh, true, true, &flags,
 768                                    ignore_quota);
 769
 770         /* we need only to store the overquota flags in the first lnb for
 771          * now, once we support multiple objects BRW, this code needs be
 772          * revised. */
 773         if (flags & QUOTA_FL_OVER_USRQUOTA)
 774                 lnb[0].flags |= OBD_BRW_OVER_USRQUOTA;
 775         if (flags & QUOTA_FL_OVER_GRPQUOTA)
 776                 lnb[0].flags |= OBD_BRW_OVER_GRPQUOTA;
 777
 778         RETURN(rc);
 779 }
 780
 781 /* Check if a block is allocated or not */
 782 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
 783                             struct niobuf_local *lnb, int npages,
 784                             struct thandle *thandle)
 785 {
 786         struct osd_thread_info *oti = osd_oti_get(env);
 787         struct osd_iobuf *iobuf = &oti->oti_iobuf;
 788         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 789         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
 790         loff_t isize;
 791         int rc = 0, i;
 792
 793         LASSERT(inode);
 794
 795         rc = osd_init_iobuf(osd, iobuf, 1, npages);
 796         if (unlikely(rc != 0))
 797                 RETURN(rc);
 798
 799         isize = i_size_read(inode);
 800         ll_vfs_dq_init(inode);
 801
 802         for (i = 0; i < npages; i++) {
 803                 if (lnb[i].rc == -ENOSPC &&
 804                     osd_is_mapped(inode, lnb[i].lnb_file_offset)) {
 805                         /* Allow the write to proceed if overwriting an
 806                          * existing block */
 807                         lnb[i].rc = 0;
 808                 }
 809
 810                 if (lnb[i].rc) { /* ENOSPC, network RPC error, etc. */
 811                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
 812                                lnb[i].rc);
 813                         LASSERT(lnb[i].page);
 814                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 815                         continue;
 816                 }
 817
 818                 LASSERT(PageLocked(lnb[i].page));
 819                 LASSERT(!PageWriteback(lnb[i].page));
 820
 821                 if (lnb[i].lnb_file_offset + lnb[i].len > isize)
 822                         isize = lnb[i].lnb_file_offset + lnb[i].len;
 823
 824                 /*
 825                  * Since write and truncate are serialized by oo_sem, even
 826                  * partial-page truncate should not leave dirty pages in the
 827                  * page cache.
 828                  */
 829                 LASSERT(!PageDirty(lnb[i].page));
 830
 831                 SetPageUptodate(lnb[i].page);
 832
 833                 osd_iobuf_add_page(iobuf, lnb[i].page);
 834         }
 835
 836         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
 837                 rc = -ENOSPC;
 838         } else if (iobuf->dr_npages > 0) {
 839                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 840                                                        iobuf->dr_npages,
 841                                                        iobuf->dr_blocks,
 842                                                        1, NULL);
 843         } else {
 844                 /* no pages to write, no transno is needed */
 845                 thandle->th_local = 1;
 846         }
 847
 848         if (likely(rc == 0)) {
 849                 if (isize > i_size_read(inode)) {
 850                         i_size_write(inode, isize);
 851                         LDISKFS_I(inode)->i_disksize = isize;
 852                         inode->i_sb->s_op->dirty_inode(inode);
 853                 }
 854
 855                 rc = osd_do_bio(osd, inode, iobuf);
 856                 /* we don't do stats here as in read path because
 857                  * write is async: we'll do this in osd_put_bufs() */
 858         }
 859
 860         if (unlikely(rc != 0)) {
 861                 /* if write fails, we should drop pages from the cache */
 862                 for (i = 0; i < npages; i++) {
 863                         if (lnb[i].page == NULL)
 864                                 continue;
 865                         LASSERT(PageLocked(lnb[i].page));
 866                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 867                 }
 868         }
 869
 870         RETURN(rc);
 871 }
 872
 873 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
 874                          struct niobuf_local *lnb, int npages)
 875 {
 876         struct osd_thread_info *oti = osd_oti_get(env);
 877         struct osd_iobuf *iobuf = &oti->oti_iobuf;
 878         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 879         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 880         struct timeval start, end;
 881         unsigned long timediff;
 882         int rc = 0, i, m = 0, cache = 0;
 883
 884         LASSERT(inode);
 885
 886         rc = osd_init_iobuf(osd, iobuf, 0, npages);
 887         if (unlikely(rc != 0))
 888                 RETURN(rc);
 889
 890         if (osd->od_read_cache)
 891                 cache = 1;
 892         if (i_size_read(inode) > osd->od_readcache_max_filesize)
 893                 cache = 0;
 894
 895         cfs_gettimeofday(&start);
 896         for (i = 0; i < npages; i++) {
 897
 898                 if (i_size_read(inode) <= lnb[i].lnb_file_offset)
 899                         /* If there's no more data, abort early.
 900                          * lnb->rc == 0, so it's easy to detect later. */
 901                         break;
 902
 903                 if (i_size_read(inode) <
 904                     lnb[i].lnb_file_offset + lnb[i].len - 1)
 905                         lnb[i].rc = i_size_read(inode) - lnb[i].lnb_file_offset;
 906                 else
 907                         lnb[i].rc = lnb[i].len;
 908                 m += lnb[i].len;
 909
 910                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS, 1);
 911                 if (PageUptodate(lnb[i].page)) {
 912                         lprocfs_counter_add(osd->od_stats,
 913                                             LPROC_OSD_CACHE_HIT, 1);
 914                 } else {
 915                         lprocfs_counter_add(osd->od_stats,
 916                                             LPROC_OSD_CACHE_MISS, 1);
 917                         osd_iobuf_add_page(iobuf, lnb[i].page);
 918                 }
 919                 if (cache == 0)
 920                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 921         }
 922         cfs_gettimeofday(&end);
 923         timediff = cfs_timeval_sub(&end, &start, NULL);
 924         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 925
 926         if (iobuf->dr_npages) {
 927                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 928                                                        iobuf->dr_npages,
 929                                                        iobuf->dr_blocks,
 930                                                        0, NULL);
 931                 rc = osd_do_bio(osd, inode, iobuf);
 932
 933                 /* IO stats will be done in osd_bufs_put() */
 934         }
 935
 936         RETURN(rc);
 937 }
 938
 939 /*
 940  * XXX: Another layering violation for now.
 941  *
 942  * We don't want to use ->f_op->read methods, because generic file write
 943  *
 944  *         - serializes on ->i_sem, and
 945  *
 946  *         - does a lot of extra work like balance_dirty_pages(),
 947  *
 948  * which doesn't work for globally shared files like /last_rcvd.
 949  */
 950 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
 951 {
 952         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
 953
 954         memcpy(buffer, (char *)ei->i_data, buflen);
 955
 956         return  buflen;
 957 }
 958
 959 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
 960 {
 961         struct buffer_head *bh;
 962         unsigned long block;
 963         int osize;
 964         int blocksize;
 965         int csize;
 966         int boffs;
 967         int err;
 968
 969         /* prevent reading after eof */
 970         spin_lock(&inode->i_lock);
 971         if (i_size_read(inode) < *offs + size) {
 972                 loff_t diff = i_size_read(inode) - *offs;
 973                 spin_unlock(&inode->i_lock);
 974                 if (diff < 0) {
 975                         CDEBUG(D_EXT2, "size %llu is too short to read @%llu\n",
 976                                i_size_read(inode), *offs);
 977                         return -EBADR;
 978                 } else if (diff == 0) {
 979                         return 0;
 980                 } else {
 981                         size = diff;
 982                 }
 983         } else {
 984                 spin_unlock(&inode->i_lock);
 985         }
 986
 987         blocksize = 1 << inode->i_blkbits;
 988         osize = size;
 989         while (size > 0) {
 990                 block = *offs >> inode->i_blkbits;
 991                 boffs = *offs & (blocksize - 1);
 992                 csize = min(blocksize - boffs, size);
 993                 bh = ldiskfs_bread(NULL, inode, block, 0, &err);
 994                 if (!bh) {
 995                         CERROR("%s: can't read %u@%llu on ino %lu: rc = %d\n",
 996                                LDISKFS_SB(inode->i_sb)->s_es->s_volume_name,
 997                                csize, *offs, inode->i_ino, err);
 998                         return err;
 999                 }
1000
1001                 memcpy(buf, bh->b_data + boffs, csize);
1002                 brelse(bh);
1003
1004                 *offs += csize;
1005                 buf += csize;
1006                 size -= csize;
1007         }
1008         return osize;
1009 }
1010
1011 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
1012                         struct lu_buf *buf, loff_t *pos,
1013                         struct lustre_capa *capa)
1014 {
1015         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1016         int           rc;
1017
1018         if (osd_object_auth(env, dt, capa, CAPA_OPC_BODY_READ))
1019                 RETURN(-EACCES);
1020
1021         /* Read small symlink from inode body as we need to maintain correct
1022          * on-disk symlinks for ldiskfs.
1023          */
1024         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
1025             (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1026                 rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
1027         else
1028                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
1029
1030         return rc;
1031 }
1032
1033 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
1034                                  const loff_t size, loff_t pos,
1035                                  struct thandle *handle)
1036 {
1037         struct osd_thandle *oh;
1038         int                 credits;
1039         struct inode       *inode;
1040         int                 rc;
1041         ENTRY;
1042
1043         LASSERT(handle != NULL);
1044
1045         oh = container_of0(handle, struct osd_thandle, ot_super);
1046         LASSERT(oh->ot_handle == NULL);
1047
1048         /* XXX: size == 0 or INT_MAX indicating a catalog header update or
1049          *      llog write, see comment in mdd_declare_llog_record().
1050          *
1051          *      This hack will be removed with llog over OSD landing
1052          */
1053         if (size == DECLARE_LLOG_REWRITE)
1054                 credits = 2;
1055         else if (size == DECLARE_LLOG_WRITE)
1056                 credits = 6;
1057         else
1058                 credits = osd_dto_credits_noquota[DTO_WRITE_BLOCK];
1059
1060         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1061
1062         inode = osd_dt_obj(dt)->oo_inode;
1063
1064         /* we may declare write to non-exist llog */
1065         if (inode == NULL)
1066                 RETURN(0);
1067
1068         /* dt_declare_write() is usually called for system objects, such
1069          * as llog or last_rcvd files. We needn't enforce quota on those
1070          * objects, so always set the lqi_space as 0. */
1071         rc = osd_declare_inode_qid(env, inode->i_uid, inode->i_gid, 0, oh,
1072                                    true, true, NULL, false);
1073         RETURN(rc);
1074 }
1075
1076 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
1077 {
1078         /* LU-2634: clear the extent format for fast symlink */
1079         ldiskfs_clear_inode_flag(inode, LDISKFS_INODE_EXTENTS);
1080
1081         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
1082         LDISKFS_I(inode)->i_disksize = buflen;
1083         i_size_write(inode, buflen);
1084         inode->i_sb->s_op->dirty_inode(inode);
1085
1086         return 0;
1087 }
1088
1089 int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
1090                              int write_NUL, loff_t *offs, handle_t *handle)
1091 {
1092         struct buffer_head *bh        = NULL;
1093         loff_t              offset    = *offs;
1094         loff_t              new_size  = i_size_read(inode);
1095         unsigned long       block;
1096         int                 blocksize = 1 << inode->i_blkbits;
1097         int                 err = 0;
1098         int                 size;
1099         int                 boffs;
1100         int                 dirty_inode = 0;
1101
1102         if (write_NUL) {
1103                 /*
1104                  * long symlink write does not count the NUL terminator in
1105                  * bufsize, we write it, and the inode's file size does not
1106                  * count the NUL terminator as well.
1107                  */
1108                 ((char *)buf)[bufsize] = '\0';
1109                 ++bufsize;
1110         }
1111         while (bufsize > 0) {
1112                 if (bh != NULL)
1113                         brelse(bh);
1114
1115                 block = offset >> inode->i_blkbits;
1116                 boffs = offset & (blocksize - 1);
1117                 size = min(blocksize - boffs, bufsize);
1118                 bh = ldiskfs_bread(handle, inode, block, 1, &err);
1119                 if (!bh) {
1120                         CERROR("%s: error reading offset %llu (block %lu): "
1121                                "rc = %d\n",
1122                                inode->i_sb->s_id, offset, block, err);
1123                         break;
1124                 }
1125
1126                 err = ldiskfs_journal_get_write_access(handle, bh);
1127                 if (err) {
1128                         CERROR("journal_get_write_access() returned error %d\n",
1129                                err);
1130                         break;
1131                 }
1132                 LASSERTF(boffs + size <= bh->b_size,
1133                          "boffs %d size %d bh->b_size %lu",
1134                          boffs, size, (unsigned long)bh->b_size);
1135                 memcpy(bh->b_data + boffs, buf, size);
1136                 err = ldiskfs_journal_dirty_metadata(handle, bh);
1137                 if (err)
1138                         break;
1139
1140                 if (offset + size > new_size)
1141                         new_size = offset + size;
1142                 offset += size;
1143                 bufsize -= size;
1144                 buf += size;
1145         }
1146         if (bh)
1147                 brelse(bh);
1148
1149         if (write_NUL)
1150                 --new_size;
1151         /* correct in-core and on-disk sizes */
1152         if (new_size > i_size_read(inode)) {
1153                 spin_lock(&inode->i_lock);
1154                 if (new_size > i_size_read(inode))
1155                         i_size_write(inode, new_size);
1156                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1157                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1158                         dirty_inode = 1;
1159                 }
1160                 spin_unlock(&inode->i_lock);
1161                 if (dirty_inode)
1162                         inode->i_sb->s_op->dirty_inode(inode);
1163         }
1164
1165         if (err == 0)
1166                 *offs = offset;
1167         return err;
1168 }
1169
1170 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1171                          const struct lu_buf *buf, loff_t *pos,
1172                          struct thandle *handle, struct lustre_capa *capa,
1173                          int ignore_quota)
1174 {
1175         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1176         struct osd_thandle      *oh;
1177         ssize_t                 result;
1178         int                     is_link;
1179
1180         LASSERT(dt_object_exists(dt));
1181
1182         if (osd_object_auth(env, dt, capa, CAPA_OPC_BODY_WRITE))
1183                 return -EACCES;
1184
1185         LASSERT(handle != NULL);
1186         LASSERT(inode != NULL);
1187         ll_vfs_dq_init(inode);
1188
1189         /* XXX: don't check: one declared chunk can be used many times */
1190         /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
1191
1192         oh = container_of(handle, struct osd_thandle, ot_super);
1193         LASSERT(oh->ot_handle->h_transaction != NULL);
1194         /* Write small symlink to inode body as we need to maintain correct
1195          * on-disk symlinks for ldiskfs.
1196          * Note: the buf->lb_buf contains a NUL terminator while buf->lb_len
1197          * does not count it in.
1198          */
1199         is_link = S_ISLNK(dt->do_lu.lo_header->loh_attr);
1200         if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1201                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1202         else
1203                 result = osd_ldiskfs_write_record(inode, buf->lb_buf,
1204                                                   buf->lb_len, is_link, pos,
1205                                                   oh->ot_handle);
1206         if (result == 0)
1207                 result = buf->lb_len;
1208         return result;
1209 }
1210
1211 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1212                              __u64 start, __u64 end, struct thandle *th)
1213 {
1214         struct osd_thandle *oh;
1215         struct inode       *inode;
1216         int                 rc;
1217         ENTRY;
1218
1219         LASSERT(th);
1220         oh = container_of(th, struct osd_thandle, ot_super);
1221
1222         /*
1223          * we don't need to reserve credits for whole truncate
1224          * it's not possible as truncate may need to free too many
1225          * blocks and that won't fit a single transaction. instead
1226          * we reserve credits to change i_size and put inode onto
1227          * orphan list. if needed truncate will extend or restart
1228          * transaction
1229          */
1230         osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
1231                              osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
1232
1233         inode = osd_dt_obj(dt)->oo_inode;
1234         LASSERT(inode);
1235
1236         rc = osd_declare_inode_qid(env, inode->i_uid, inode->i_gid, 0, oh,
1237                                    true, true, NULL, false);
1238         RETURN(rc);
1239 }
1240
1241 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1242                      __u64 start, __u64 end, struct thandle *th,
1243                      struct lustre_capa *capa)
1244 {
1245         struct osd_thandle *oh;
1246         struct osd_object  *obj = osd_dt_obj(dt);
1247         struct inode       *inode = obj->oo_inode;
1248         handle_t           *h;
1249         tid_t               tid;
1250         int                 rc, rc2 = 0;
1251         ENTRY;
1252
1253         LASSERT(end == OBD_OBJECT_EOF);
1254         LASSERT(dt_object_exists(dt));
1255         LASSERT(osd_invariant(obj));
1256         LASSERT(inode != NULL);
1257         ll_vfs_dq_init(inode);
1258
1259         LASSERT(th);
1260         oh = container_of(th, struct osd_thandle, ot_super);
1261         LASSERT(oh->ot_handle->h_transaction != NULL);
1262
1263         osd_trans_exec_op(env, th, OSD_OT_PUNCH);
1264
1265         tid = oh->ot_handle->h_transaction->t_tid;
1266
1267         rc = vmtruncate(inode, start);
1268
1269         /*
1270          * For a partial-page truncate, flush the page to disk immediately to
1271          * avoid data corruption during direct disk write.  b=17397
1272          */
1273         if (rc == 0 && (start & ~CFS_PAGE_MASK) != 0)
1274                 rc = filemap_fdatawrite_range(inode->i_mapping, start, start+1);
1275
1276         h = journal_current_handle();
1277         LASSERT(h != NULL);
1278         LASSERT(h == oh->ot_handle);
1279
1280         if (tid != h->h_transaction->t_tid) {
1281                 int credits = oh->ot_credits;
1282                 /*
1283                  * transaction has changed during truncate
1284                  * we need to restart the handle with our credits
1285                  */
1286                 if (h->h_buffer_credits < credits) {
1287                         if (ldiskfs_journal_extend(h, credits))
1288                                 rc2 = ldiskfs_journal_restart(h, credits);
1289                 }
1290         }
1291
1292         RETURN(rc == 0 ? rc2 : rc);
1293 }
1294
1295 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
1296                           struct ll_user_fiemap *fm)
1297 {
1298         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1299         struct osd_thread_info *info   = osd_oti_get(env);
1300         struct dentry          *dentry = &info->oti_obj_dentry;
1301         struct file            *file   = &info->oti_file;
1302         mm_segment_t            saved_fs;
1303         int rc;
1304
1305         LASSERT(inode);
1306         dentry->d_inode = inode;
1307         file->f_dentry = dentry;
1308         file->f_mapping = inode->i_mapping;
1309         file->f_op = inode->i_fop;
1310
1311         saved_fs = get_fs();
1312         set_fs(get_ds());
1313         /* ldiskfs_ioctl does not have a inode argument */
1314         if (inode->i_fop->unlocked_ioctl)
1315                 rc = inode->i_fop->unlocked_ioctl(file, FSFILT_IOC_FIEMAP,
1316                                                   (long)fm);
1317         else
1318                 rc = -ENOTTY;
1319         set_fs(saved_fs);
1320         return rc;
1321 }
1322
1323 /*
1324  * in some cases we may need declare methods for objects being created
1325  * e.g., when we create symlink
1326  */
1327 const struct dt_body_operations osd_body_ops_new = {
1328         .dbo_declare_write = osd_declare_write,
1329 };
1330
1331 const struct dt_body_operations osd_body_ops = {
1332         .dbo_read                 = osd_read,
1333         .dbo_declare_write        = osd_declare_write,
1334         .dbo_write                = osd_write,
1335         .dbo_bufs_get             = osd_bufs_get,
1336         .dbo_bufs_put             = osd_bufs_put,
1337         .dbo_write_prep           = osd_write_prep,
1338         .dbo_declare_write_commit = osd_declare_write_commit,
1339         .dbo_write_commit         = osd_write_commit,
1340         .dbo_read_prep            = osd_read_prep,
1341         .do_declare_punch         = osd_declare_punch,
1342         .do_punch                 = osd_punch,
1343         .dbo_fiemap_get           = osd_fiemap_get,
1344 };
1345