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.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2012, 2016, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  *
  32  * lustre/osd/osd_io.c
  33  *
  34  * body operations
  35  *
  36  * Author: Nikita Danilov <nikita@clusterfs.com>
  37  * Author: Alex Zhuravlev <bzzz@whamcloud.com>
  38  *
  39  */
  40
  41 /* LUSTRE_VERSION_CODE */
  42 #include <lustre_ver.h>
  43 /* prerequisite for linux/xattr.h */
  44 #include <linux/types.h>
  45 /* prerequisite for linux/xattr.h */
  46 #include <linux/fs.h>
  47
  48 /*
  49  * struct OBD_{ALLOC,FREE}*()
  50  * OBD_FAIL_CHECK
  51  */
  52 #include <obd_support.h>
  53
  54 #include "osd_internal.h"
  55
  56 /* ext_depth() */
  57 #include <ldiskfs/ldiskfs_extents.h>
  58
  59 static int __osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,
  60                             int rw, int line, int pages)
  61 {
  62         int blocks, i;
  63
  64         LASSERTF(iobuf->dr_elapsed_valid == 0,
  65                  "iobuf %p, reqs %d, rw %d, line %d\n", iobuf,
  66                  atomic_read(&iobuf->dr_numreqs), iobuf->dr_rw,
  67                  iobuf->dr_init_at);
  68         LASSERT(pages <= PTLRPC_MAX_BRW_PAGES);
  69
  70         init_waitqueue_head(&iobuf->dr_wait);
  71         atomic_set(&iobuf->dr_numreqs, 0);
  72         iobuf->dr_npages = 0;
  73         iobuf->dr_error = 0;
  74         iobuf->dr_dev = d;
  75         iobuf->dr_frags = 0;
  76         iobuf->dr_elapsed = 0;
  77         /* must be counted before, so assert */
  78         iobuf->dr_rw = rw;
  79         iobuf->dr_init_at = line;
  80
  81         blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
  82         if (iobuf->dr_bl_buf.lb_len >= blocks * sizeof(iobuf->dr_blocks[0])) {
  83                 LASSERT(iobuf->dr_pg_buf.lb_len >=
  84                         pages * sizeof(iobuf->dr_pages[0]));
  85                 return 0;
  86         }
  87
  88         /* start with 1MB for 4K blocks */
  89         i = 256;
  90         while (i <= PTLRPC_MAX_BRW_PAGES && i < pages)
  91                 i <<= 1;
  92
  93         CDEBUG(D_OTHER, "realloc %u for %u (%u) pages\n",
  94                (unsigned)(pages * sizeof(iobuf->dr_pages[0])), i, pages);
  95         pages = i;
  96         blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
  97         iobuf->dr_max_pages = 0;
  98         CDEBUG(D_OTHER, "realloc %u for %u blocks\n",
  99                (unsigned)(blocks * sizeof(iobuf->dr_blocks[0])), blocks);
 100
 101         lu_buf_realloc(&iobuf->dr_bl_buf, blocks * sizeof(iobuf->dr_blocks[0]));
 102         iobuf->dr_blocks = iobuf->dr_bl_buf.lb_buf;
 103         if (unlikely(iobuf->dr_blocks == NULL))
 104                 return -ENOMEM;
 105
 106         lu_buf_realloc(&iobuf->dr_pg_buf, pages * sizeof(iobuf->dr_pages[0]));
 107         iobuf->dr_pages = iobuf->dr_pg_buf.lb_buf;
 108         if (unlikely(iobuf->dr_pages == NULL))
 109                 return -ENOMEM;
 110
 111         iobuf->dr_max_pages = pages;
 112
 113         return 0;
 114 }
 115 #define osd_init_iobuf(dev, iobuf, rw, pages) \
 116         __osd_init_iobuf(dev, iobuf, rw, __LINE__, pages)
 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 #ifndef REQ_WRITE /* pre-2.6.35 */
 141 #define __REQ_WRITE BIO_RW
 142 #endif
 143
 144 #ifdef HAVE_BIO_ENDIO_USES_ONE_ARG
 145 static void dio_complete_routine(struct bio *bio)
 146 {
 147         int error = bio->bi_error;
 148 #else
 149 static void dio_complete_routine(struct bio *bio, int error)
 150 {
 151 #endif
 152         struct osd_iobuf *iobuf = bio->bi_private;
 153         int iter;
 154         struct bio_vec *bvl;
 155
 156         /* CAVEAT EMPTOR: possibly in IRQ context
 157          * DO NOT record procfs stats here!!! */
 158
 159         if (unlikely(iobuf == NULL)) {
 160                 CERROR("***** bio->bi_private is NULL!  This should never "
 161                        "happen.  Normally, I would crash here, but instead I "
 162                        "will dump the bio contents to the console.  Please "
 163                        "report this to <https://jira.hpdd.intel.com/> , along "
 164                        "with any interesting messages leading up to this point "
 165                        "(like SCSI errors, perhaps).  Because bi_private is "
 166                        "NULL, I can't wake up the thread that initiated this "
 167                        "IO - you will probably have to reboot this node.\n");
 168                 CERROR("bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d, "
 169                        "bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, "
 170                        "bi_private: %p\n", bio->bi_next,
 171                         (unsigned long)bio->bi_flags,
 172                         bio->bi_rw, bio->bi_vcnt, bio_idx(bio),
 173                         bio_sectors(bio) << 9, bio->bi_end_io,
 174 #ifdef HAVE_BI_CNT
 175                         atomic_read(&bio->bi_cnt),
 176 #else
 177                         atomic_read(&bio->__bi_cnt),
 178 #endif
 179                         bio->bi_private);
 180                 return;
 181         }
 182
 183         /* the check is outside of the cycle for performance reason -bzzz */
 184         if (!test_bit(__REQ_WRITE, &bio->bi_rw)) {
 185                 bio_for_each_segment_all(bvl, bio, iter) {
 186                         if (likely(error == 0))
 187                                 SetPageUptodate(bvl_to_page(bvl));
 188                         LASSERT(PageLocked(bvl_to_page(bvl)));
 189                 }
 190                 atomic_dec(&iobuf->dr_dev->od_r_in_flight);
 191         } else {
 192                 atomic_dec(&iobuf->dr_dev->od_w_in_flight);
 193         }
 194
 195         /* any real error is good enough -bzzz */
 196         if (error != 0 && iobuf->dr_error == 0)
 197                 iobuf->dr_error = error;
 198
 199         /*
 200          * set dr_elapsed before dr_numreqs turns to 0, otherwise
 201          * it's possible that service thread will see dr_numreqs
 202          * is zero, but dr_elapsed is not set yet, leading to lost
 203          * data in this processing and an assertion in a subsequent
 204          * call to OSD.
 205          */
 206         if (atomic_read(&iobuf->dr_numreqs) == 1) {
 207                 iobuf->dr_elapsed = jiffies - iobuf->dr_start_time;
 208                 iobuf->dr_elapsed_valid = 1;
 209         }
 210         if (atomic_dec_and_test(&iobuf->dr_numreqs))
 211                 wake_up(&iobuf->dr_wait);
 212
 213         /* Completed bios used to be chained off iobuf->dr_bios and freed in
 214          * filter_clear_dreq().  It was then possible to exhaust the biovec-256
 215          * mempool when serious on-disk fragmentation was encountered,
 216          * deadlocking the OST.  The bios are now released as soon as complete
 217          * so the pool cannot be exhausted while IOs are competing. bug 10076 */
 218         bio_put(bio);
 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         atomic_inc(&iobuf->dr_numreqs);
 228
 229         if (iobuf->dr_rw == 0) {
 230                 atomic_inc(&osd->od_r_in_flight);
 231                 lprocfs_oh_tally(&h[BRW_R_RPC_HIST],
 232                                  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                 atomic_inc(&osd->od_w_in_flight);
 236                 lprocfs_oh_tally(&h[BRW_W_RPC_HIST],
 237                                  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         if (bio == NULL)
 256                 return 0;
 257
 258         return bio_end_sector(bio) == sector ? 1 : 0;
 259 }
 260
 261 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
 262                       struct osd_iobuf *iobuf)
 263 {
 264         int            blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 265         struct page  **pages = iobuf->dr_pages;
 266         int            npages = iobuf->dr_npages;
 267         sector_t      *blocks = iobuf->dr_blocks;
 268         int            total_blocks = npages * blocks_per_page;
 269         int            sector_bits = inode->i_sb->s_blocksize_bits - 9;
 270         unsigned int   blocksize = inode->i_sb->s_blocksize;
 271         struct bio    *bio = NULL;
 272         struct page   *page;
 273         unsigned int   page_offset;
 274         sector_t       sector;
 275         int            nblocks;
 276         int            block_idx;
 277         int            page_idx;
 278         int            i;
 279         int            rc = 0;
 280         ENTRY;
 281
 282         LASSERT(iobuf->dr_npages == npages);
 283
 284         osd_brw_stats_update(osd, iobuf);
 285         iobuf->dr_start_time = cfs_time_current();
 286
 287         for (page_idx = 0, block_idx = 0;
 288              page_idx < npages;
 289              page_idx++, block_idx += blocks_per_page) {
 290
 291                 page = pages[page_idx];
 292                 LASSERT(block_idx + blocks_per_page <= total_blocks);
 293
 294                 for (i = 0, page_offset = 0;
 295                      i < blocks_per_page;
 296                      i += nblocks, page_offset += blocksize * nblocks) {
 297
 298                         nblocks = 1;
 299
 300                         if (blocks[block_idx + i] == 0) {  /* hole */
 301                                 LASSERTF(iobuf->dr_rw == 0,
 302                                          "page_idx %u, block_idx %u, i %u\n",
 303                                          page_idx, block_idx, i);
 304                                 memset(kmap(page) + page_offset, 0, blocksize);
 305                                 kunmap(page);
 306                                 continue;
 307                         }
 308
 309                         sector = (sector_t)blocks[block_idx + i] << sector_bits;
 310
 311                         /* Additional contiguous file blocks? */
 312                         while (i + nblocks < blocks_per_page &&
 313                                (sector + (nblocks << sector_bits)) ==
 314                                ((sector_t)blocks[block_idx + i + nblocks] <<
 315                                 sector_bits))
 316                                 nblocks++;
 317
 318                         if (bio != NULL &&
 319                             can_be_merged(bio, sector) &&
 320                             bio_add_page(bio, page,
 321                                          blocksize * nblocks, page_offset) != 0)
 322                                 continue;       /* added this frag OK */
 323
 324                         if (bio != NULL) {
 325                                 struct request_queue *q =
 326                                         bdev_get_queue(bio->bi_bdev);
 327                                 unsigned int bi_size = bio_sectors(bio) << 9;
 328
 329                                 /* Dang! I have to fragment this I/O */
 330                                 CDEBUG(D_INODE, "bio++ sz %d vcnt %d(%d) "
 331                                        "sectors %d(%d) psg %d(%d) hsg %d(%d)\n",
 332                                        bi_size, bio->bi_vcnt, bio->bi_max_vecs,
 333                                        bio_sectors(bio),
 334                                        queue_max_sectors(q),
 335                                        bio_phys_segments(q, bio),
 336                                        queue_max_phys_segments(q),
 337                                        0, queue_max_hw_segments(q));
 338                                 record_start_io(iobuf, bi_size);
 339                                 osd_submit_bio(iobuf->dr_rw, bio);
 340                         }
 341
 342                         /* allocate new bio */
 343                         bio = bio_alloc(GFP_NOIO, min(BIO_MAX_PAGES,
 344                                                       (npages - page_idx) *
 345                                                       blocks_per_page));
 346                         if (bio == NULL) {
 347                                 CERROR("Can't allocate bio %u*%u = %u pages\n",
 348                                        (npages - page_idx), blocks_per_page,
 349                                        (npages - page_idx) * blocks_per_page);
 350                                 rc = -ENOMEM;
 351                                 goto out;
 352                         }
 353
 354                         bio->bi_bdev = inode->i_sb->s_bdev;
 355                         bio_set_sector(bio, sector);
 356                         bio->bi_rw = (iobuf->dr_rw == 0) ? READ : WRITE;
 357                         bio->bi_end_io = dio_complete_routine;
 358                         bio->bi_private = iobuf;
 359
 360                         rc = bio_add_page(bio, page,
 361                                           blocksize * nblocks, page_offset);
 362                         LASSERT(rc != 0);
 363                 }
 364         }
 365
 366         if (bio != NULL) {
 367                 record_start_io(iobuf, bio_sectors(bio) << 9);
 368                 osd_submit_bio(iobuf->dr_rw, bio);
 369                 rc = 0;
 370         }
 371
 372 out:
 373         /* in order to achieve better IO throughput, we don't wait for writes
 374          * completion here. instead we proceed with transaction commit in
 375          * parallel and wait for IO completion once transaction is stopped
 376          * see osd_trans_stop() for more details -bzzz */
 377         if (iobuf->dr_rw == 0) {
 378                 wait_event(iobuf->dr_wait,
 379                            atomic_read(&iobuf->dr_numreqs) == 0);
 380                 osd_fini_iobuf(osd, iobuf);
 381         }
 382
 383         if (rc == 0)
 384                 rc = iobuf->dr_error;
 385         RETURN(rc);
 386 }
 387
 388 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
 389                                    struct niobuf_local *lnb)
 390 {
 391         ENTRY;
 392
 393         *nrpages = 0;
 394
 395         while (len > 0) {
 396                 int poff = offset & (PAGE_SIZE - 1);
 397                 int plen = PAGE_SIZE - poff;
 398
 399                 if (plen > len)
 400                         plen = len;
 401                 lnb->lnb_file_offset = offset;
 402                 lnb->lnb_page_offset = poff;
 403                 lnb->lnb_len = plen;
 404                 /* lnb->lnb_flags = rnb->rnb_flags; */
 405                 lnb->lnb_flags = 0;
 406                 lnb->lnb_page = NULL;
 407                 lnb->lnb_rc = 0;
 408
 409                 LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
 410                          (long long) len);
 411                 offset += plen;
 412                 len -= plen;
 413                 lnb++;
 414                 (*nrpages)++;
 415         }
 416
 417         RETURN(0);
 418 }
 419
 420 static struct page *osd_get_page(struct dt_object *dt, loff_t offset, int rw)
 421 {
 422         struct inode      *inode = osd_dt_obj(dt)->oo_inode;
 423         struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
 424         struct page       *page;
 425
 426         LASSERT(inode);
 427
 428         page = find_or_create_page(inode->i_mapping, offset >> PAGE_SHIFT,
 429                                    GFP_NOFS | __GFP_HIGHMEM);
 430         if (unlikely(page == NULL))
 431                 lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
 432
 433         return page;
 434 }
 435
 436 /*
 437  * there are following "locks":
 438  * journal_start
 439  * i_mutex
 440  * page lock
 441  *
 442  * osd write path:
 443  *  - lock page(s)
 444  *  - journal_start
 445  *  - truncate_sem
 446  *
 447  * ext4 vmtruncate:
 448  *  - lock pages, unlock
 449  *  - journal_start
 450  *  - lock partial page
 451  *  - i_data_sem
 452  *
 453  */
 454
 455 /**
 456  * Unlock and release pages loaded by osd_bufs_get()
 457  *
 458  * Unlock \a npages pages from \a lnb and drop the refcount on them.
 459  *
 460  * \param env           thread execution environment
 461  * \param dt            dt object undergoing IO (OSD object + methods)
 462  * \param lnb           array of pages undergoing IO
 463  * \param npages        number of pages in \a lnb
 464  *
 465  * \retval 0            always
 466  */
 467 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 468                         struct niobuf_local *lnb, int npages)
 469 {
 470         int i;
 471
 472         for (i = 0; i < npages; i++) {
 473                 if (lnb[i].lnb_page == NULL)
 474                         continue;
 475                 LASSERT(PageLocked(lnb[i].lnb_page));
 476                 unlock_page(lnb[i].lnb_page);
 477                 put_page(lnb[i].lnb_page);
 478                 lu_object_put(env, &dt->do_lu);
 479                 lnb[i].lnb_page = NULL;
 480         }
 481
 482         RETURN(0);
 483 }
 484
 485 /**
 486  * Load and lock pages undergoing IO
 487  *
 488  * Pages as described in the \a lnb array are fetched (from disk or cache)
 489  * and locked for IO by the caller.
 490  *
 491  * DLM locking protects us from write and truncate competing for same region,
 492  * but partial-page truncate can leave dirty pages in the cache for ldiskfs.
 493  * It's possible the writeout on a such a page is in progress when we access
 494  * it. It's also possible that during this writeout we put new (partial) data
 495  * into the page, but won't be able to proceed in filter_commitrw_write().
 496  * Therefore, just wait for writeout completion as it should be rare enough.
 497  *
 498  * \param env           thread execution environment
 499  * \param dt            dt object undergoing IO (OSD object + methods)
 500  * \param pos           byte offset of IO start
 501  * \param len           number of bytes of IO
 502  * \param lnb           array of extents undergoing IO
 503  * \param rw            read or write operation?
 504  * \param capa          capabilities
 505  *
 506  * \retval pages        (zero or more) loaded successfully
 507  * \retval -ENOMEM      on memory/page allocation error
 508  */
 509 static int osd_bufs_get(const struct lu_env *env, struct dt_object *dt,
 510                         loff_t pos, ssize_t len, struct niobuf_local *lnb,
 511                         int rw)
 512 {
 513         struct osd_object   *obj    = osd_dt_obj(dt);
 514         int npages, i, rc = 0;
 515
 516         LASSERT(obj->oo_inode);
 517
 518         osd_map_remote_to_local(pos, len, &npages, lnb);
 519
 520         for (i = 0; i < npages; i++, lnb++) {
 521                 lnb->lnb_page = osd_get_page(dt, lnb->lnb_file_offset, rw);
 522                 if (lnb->lnb_page == NULL)
 523                         GOTO(cleanup, rc = -ENOMEM);
 524
 525                 wait_on_page_writeback(lnb->lnb_page);
 526                 BUG_ON(PageWriteback(lnb->lnb_page));
 527
 528                 lu_object_get(&dt->do_lu);
 529         }
 530
 531         RETURN(i);
 532
 533 cleanup:
 534         if (i > 0)
 535                 osd_bufs_put(env, dt, lnb - i, i);
 536         return rc;
 537 }
 538
 539 #ifndef HAVE_LDISKFS_MAP_BLOCKS
 540
 541 #ifdef HAVE_EXT_PBLOCK /* Name changed to ext4_ext_pblock for kernel 2.6.35 */
 542 #define ldiskfs_ext_pblock(ex) ext_pblock((ex))
 543 #endif
 544
 545 struct bpointers {
 546         sector_t *blocks;
 547         unsigned long start;
 548         int num;
 549         int init_num;
 550         int create;
 551 };
 552
 553 static long ldiskfs_ext_find_goal(struct inode *inode,
 554                                   struct ldiskfs_ext_path *path,
 555                                   unsigned long block, int *aflags)
 556 {
 557         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
 558         unsigned long bg_start;
 559         unsigned long colour;
 560         int depth;
 561
 562         if (path) {
 563                 struct ldiskfs_extent *ex;
 564                 depth = path->p_depth;
 565
 566                 /* try to predict block placement */
 567                 if ((ex = path[depth].p_ext))
 568                         return ldiskfs_ext_pblock(ex) +
 569                                 (block - le32_to_cpu(ex->ee_block));
 570
 571                 /* it looks index is empty
 572                  * try to find starting from index itself */
 573                 if (path[depth].p_bh)
 574                         return path[depth].p_bh->b_blocknr;
 575         }
 576
 577         /* OK. use inode's group */
 578         bg_start = (ei->i_block_group * LDISKFS_BLOCKS_PER_GROUP(inode->i_sb)) +
 579                 le32_to_cpu(LDISKFS_SB(inode->i_sb)->s_es->s_first_data_block);
 580         colour = (current->pid % 16) *
 581                 (LDISKFS_BLOCKS_PER_GROUP(inode->i_sb) / 16);
 582         return bg_start + colour + block;
 583 }
 584
 585 static unsigned long new_blocks(handle_t *handle, struct inode *inode,
 586                                 struct ldiskfs_ext_path *path,
 587                                 unsigned long block, unsigned long *count,
 588                                 int *err)
 589 {
 590         struct ldiskfs_allocation_request ar;
 591         unsigned long pblock;
 592         int aflags;
 593
 594         /* find neighbour allocated blocks */
 595         ar.lleft = block;
 596         *err = ldiskfs_ext_search_left(inode, path, &ar.lleft, &ar.pleft);
 597         if (*err)
 598                 return 0;
 599         ar.lright = block;
 600         *err = ldiskfs_ext_search_right(inode, path, &ar.lright, &ar.pright);
 601         if (*err)
 602                 return 0;
 603
 604         /* allocate new block */
 605         ar.goal = ldiskfs_ext_find_goal(inode, path, block, &aflags);
 606         ar.inode = inode;
 607         ar.logical = block;
 608         ar.len = *count;
 609         ar.flags = LDISKFS_MB_HINT_DATA;
 610         pblock = ldiskfs_mb_new_blocks(handle, &ar, err);
 611         *count = ar.len;
 612         return pblock;
 613 }
 614
 615 static int ldiskfs_ext_new_extent_cb(struct inode *inode,
 616                                      struct ldiskfs_ext_path *path,
 617                                      struct ldiskfs_ext_cache *cex,
 618 #ifdef HAVE_EXT_PREPARE_CB_EXTENT
 619                                      struct ldiskfs_extent *ex,
 620 #endif
 621                                      void *cbdata)
 622 {
 623         struct bpointers *bp = cbdata;
 624         struct ldiskfs_extent nex;
 625         unsigned long pblock = 0;
 626         unsigned long tgen;
 627         int err, i;
 628         unsigned long count;
 629         handle_t *handle;
 630
 631 #ifdef LDISKFS_EXT_CACHE_EXTENT /* until kernel 2.6.37 */
 632         if (cex->ec_type == LDISKFS_EXT_CACHE_EXTENT) {
 633 #else
 634         if ((cex->ec_len != 0) && (cex->ec_start != 0)) {
 635 #endif
 636                 err = EXT_CONTINUE;
 637                 goto map;
 638         }
 639
 640         if (bp->create == 0) {
 641                 i = 0;
 642                 if (cex->ec_block < bp->start)
 643                         i = bp->start - cex->ec_block;
 644                 if (i >= cex->ec_len)
 645                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 646                                         i, cex->ec_len);
 647                 for (; i < cex->ec_len && bp->num; i++) {
 648                         *(bp->blocks) = 0;
 649                         bp->blocks++;
 650                         bp->num--;
 651                         bp->start++;
 652                 }
 653
 654                 return EXT_CONTINUE;
 655         }
 656
 657         tgen = LDISKFS_I(inode)->i_ext_generation;
 658         count = ldiskfs_ext_calc_credits_for_insert(inode, path);
 659
 660         handle = osd_journal_start(inode, LDISKFS_HT_MISC,
 661                                    count + LDISKFS_ALLOC_NEEDED + 1);
 662         if (IS_ERR(handle)) {
 663                 return PTR_ERR(handle);
 664         }
 665
 666         if (tgen != LDISKFS_I(inode)->i_ext_generation) {
 667                 /* the tree has changed. so path can be invalid at moment */
 668                 ldiskfs_journal_stop(handle);
 669                 return EXT_REPEAT;
 670         }
 671
 672         /* In 2.6.32 kernel, ldiskfs_ext_walk_space()'s callback func is not
 673          * protected by i_data_sem as whole. so we patch it to store
 674          * generation to path and now verify the tree hasn't changed */
 675         down_write((&LDISKFS_I(inode)->i_data_sem));
 676
 677         /* validate extent, make sure the extent tree does not changed */
 678         if (LDISKFS_I(inode)->i_ext_generation != path[0].p_generation) {
 679                 /* cex is invalid, try again */
 680                 up_write(&LDISKFS_I(inode)->i_data_sem);
 681                 ldiskfs_journal_stop(handle);
 682                 return EXT_REPEAT;
 683         }
 684
 685         count = cex->ec_len;
 686         pblock = new_blocks(handle, inode, path, cex->ec_block, &count, &err);
 687         if (!pblock)
 688                 goto out;
 689         BUG_ON(count > cex->ec_len);
 690
 691         /* insert new extent */
 692         nex.ee_block = cpu_to_le32(cex->ec_block);
 693         ldiskfs_ext_store_pblock(&nex, pblock);
 694         nex.ee_len = cpu_to_le16(count);
 695         err = ldiskfs_ext_insert_extent(handle, inode, path, &nex, 0);
 696         if (err) {
 697                 /* free data blocks we just allocated */
 698                 /* not a good idea to call discard here directly,
 699                  * but otherwise we'd need to call it every free() */
 700                 ldiskfs_discard_preallocations(inode);
 701 #ifdef HAVE_EXT_FREE_BLOCK_WITH_BUFFER_HEAD /* Introduced in 2.6.32-rc7 */
 702                 ldiskfs_free_blocks(handle, inode, NULL,
 703                                     ldiskfs_ext_pblock(&nex),
 704                                     le16_to_cpu(nex.ee_len), 0);
 705 #else
 706                 ldiskfs_free_blocks(handle, inode, ldiskfs_ext_pblock(&nex),
 707                                     le16_to_cpu(nex.ee_len), 0);
 708 #endif
 709                 goto out;
 710         }
 711
 712         /*
 713          * Putting len of the actual extent we just inserted,
 714          * we are asking ldiskfs_ext_walk_space() to continue
 715          * scaning after that block
 716          */
 717         cex->ec_len = le16_to_cpu(nex.ee_len);
 718         cex->ec_start = ldiskfs_ext_pblock(&nex);
 719         BUG_ON(le16_to_cpu(nex.ee_len) == 0);
 720         BUG_ON(le32_to_cpu(nex.ee_block) != cex->ec_block);
 721
 722 out:
 723         up_write((&LDISKFS_I(inode)->i_data_sem));
 724         ldiskfs_journal_stop(handle);
 725 map:
 726         if (err >= 0) {
 727                 /* map blocks */
 728                 if (bp->num == 0) {
 729                         CERROR("hmm. why do we find this extent?\n");
 730                         CERROR("initial space: %lu:%u\n",
 731                                 bp->start, bp->init_num);
 732 #ifdef LDISKFS_EXT_CACHE_EXTENT /* until kernel 2.6.37 */
 733                         CERROR("current extent: %u/%u/%llu %d\n",
 734                                 cex->ec_block, cex->ec_len,
 735                                 (unsigned long long)cex->ec_start,
 736                                 cex->ec_type);
 737 #else
 738                         CERROR("current extent: %u/%u/%llu\n",
 739                                 cex->ec_block, cex->ec_len,
 740                                 (unsigned long long)cex->ec_start);
 741 #endif
 742                 }
 743                 i = 0;
 744                 if (cex->ec_block < bp->start)
 745                         i = bp->start - cex->ec_block;
 746                 if (i >= cex->ec_len)
 747                         CERROR("nothing to do?! i = %d, e_num = %u\n",
 748                                         i, cex->ec_len);
 749                 for (; i < cex->ec_len && bp->num; i++) {
 750                         *(bp->blocks) = cex->ec_start + i;
 751                         if (pblock != 0) {
 752                                 /* unmap any possible underlying metadata from
 753                                  * the block device mapping.  bug 6998. */
 754                                 unmap_underlying_metadata(inode->i_sb->s_bdev,
 755                                                           *(bp->blocks));
 756                         }
 757                         bp->blocks++;
 758                         bp->num--;
 759                         bp->start++;
 760                 }
 761         }
 762         return err;
 763 }
 764
 765 static int osd_ldiskfs_map_nblocks(struct inode *inode, unsigned long index,
 766                                    int clen, sector_t *blocks, int create)
 767 {
 768         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 769         struct bpointers bp;
 770         int err;
 771
 772         if (index + clen >= inode->i_sb->s_maxbytes >> PAGE_SHIFT)
 773                 return -EFBIG;
 774
 775         bp.blocks = blocks;
 776         bp.start = index * blocks_per_page;
 777         bp.init_num = bp.num = clen * blocks_per_page;
 778         bp.create = create;
 779
 780         CDEBUG(D_OTHER, "blocks %lu-%lu requested for inode %u\n",
 781                bp.start, bp.start + bp.num - 1, (unsigned)inode->i_ino);
 782
 783         err = ldiskfs_ext_walk_space(inode, bp.start, bp.num,
 784                                      ldiskfs_ext_new_extent_cb, &bp);
 785         ldiskfs_ext_invalidate_cache(inode);
 786
 787         return err;
 788 }
 789
 790 static int osd_ldiskfs_map_bm_inode_pages(struct inode *inode,
 791                                           struct page **page, int pages,
 792                                           sector_t *blocks, int create)
 793 {
 794         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 795         pgoff_t bitmap_max_page_index;
 796         sector_t *b;
 797         int rc = 0, i;
 798
 799         bitmap_max_page_index = LDISKFS_SB(inode->i_sb)->s_bitmap_maxbytes >>
 800                                 PAGE_SHIFT;
 801         for (i = 0, b = blocks; i < pages; i++, page++) {
 802                 if ((*page)->index + 1 >= bitmap_max_page_index) {
 803                         rc = -EFBIG;
 804                         break;
 805                 }
 806                 rc = ldiskfs_map_inode_page(inode, *page, b, create);
 807                 if (rc) {
 808                         CERROR("ino %lu, blk %llu create %d: rc %d\n",
 809                                inode->i_ino,
 810                                (unsigned long long)*b, create, rc);
 811                         break;
 812                 }
 813                 b += blocks_per_page;
 814         }
 815         return rc;
 816 }
 817
 818 static int osd_ldiskfs_map_ext_inode_pages(struct inode *inode,
 819                                            struct page **page,
 820                                            int pages, sector_t *blocks,
 821                                            int create)
 822 {
 823         int rc = 0, i = 0, clen = 0;
 824         struct page *fp = NULL;
 825
 826         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 827                 inode->i_ino, pages, (*page)->index);
 828
 829         /* pages are sorted already. so, we just have to find
 830          * contig. space and process them properly */
 831         while (i < pages) {
 832                 if (fp == NULL) {
 833                         /* start new extent */
 834                         fp = *page++;
 835                         clen = 1;
 836                         i++;
 837                         continue;
 838                 } else if (fp->index + clen == (*page)->index) {
 839                         /* continue the extent */
 840                         page++;
 841                         clen++;
 842                         i++;
 843                         continue;
 844                 }
 845
 846                 /* process found extent */
 847                 rc = osd_ldiskfs_map_nblocks(inode, fp->index, clen,
 848                                              blocks, create);
 849                 if (rc)
 850                         GOTO(cleanup, rc);
 851
 852                 /* look for next extent */
 853                 fp = NULL;
 854                 blocks += clen * (PAGE_SIZE >> inode->i_blkbits);
 855         }
 856
 857         if (fp)
 858                 rc = osd_ldiskfs_map_nblocks(inode, fp->index, clen,
 859                                              blocks, create);
 860
 861 cleanup:
 862         return rc;
 863 }
 864
 865 static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
 866                                        int pages, sector_t *blocks,
 867                                        int create)
 868 {
 869         int rc;
 870
 871         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
 872                 rc = osd_ldiskfs_map_ext_inode_pages(inode, page, pages,
 873                                                      blocks, create);
 874                 return rc;
 875         }
 876         rc = osd_ldiskfs_map_bm_inode_pages(inode, page, pages, blocks, create);
 877
 878         return rc;
 879 }
 880 #else
 881 static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
 882                                        int pages, sector_t *blocks,
 883                                        int create)
 884 {
 885         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 886         int rc = 0, i = 0;
 887         struct page *fp = NULL;
 888         int clen = 0;
 889         pgoff_t max_page_index;
 890
 891         max_page_index = inode->i_sb->s_maxbytes >> PAGE_SHIFT;
 892
 893         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 894                 inode->i_ino, pages, (*page)->index);
 895
 896         /* pages are sorted already. so, we just have to find
 897          * contig. space and process them properly */
 898         while (i < pages) {
 899                 long blen, total = 0;
 900                 handle_t *handle = NULL;
 901                 struct ldiskfs_map_blocks map = { 0 };
 902
 903                 if (fp == NULL) { /* start new extent */
 904                         fp = *page++;
 905                         clen = 1;
 906                         if (++i != pages)
 907                                 continue;
 908                 } else if (fp->index + clen == (*page)->index) {
 909                         /* continue the extent */
 910                         page++;
 911                         clen++;
 912                         if (++i != pages)
 913                                 continue;
 914                 }
 915                 if (fp->index + clen >= max_page_index)
 916                         GOTO(cleanup, rc = -EFBIG);
 917                 /* process found extent */
 918                 map.m_lblk = fp->index * blocks_per_page;
 919                 map.m_len = blen = clen * blocks_per_page;
 920                 if (create) {
 921                         create = LDISKFS_GET_BLOCKS_CREATE;
 922                         handle = ldiskfs_journal_current_handle();
 923                         LASSERT(handle != NULL);
 924                 }
 925 cont_map:
 926                 rc = ldiskfs_map_blocks(handle, inode, &map, create);
 927                 if (rc >= 0) {
 928                         int c = 0;
 929                         for (; total < blen && c < map.m_len; c++, total++) {
 930                                 if (rc == 0) {
 931                                         *(blocks + total) = 0;
 932                                         total++;
 933                                         break;
 934                                 } else {
 935                                         *(blocks + total) = map.m_pblk + c;
 936                                         /* unmap any possible underlying
 937                                          * metadata from the block device
 938                                          * mapping.  bug 6998. */
 939                                         if ((map.m_flags & LDISKFS_MAP_NEW) &&
 940                                             create)
 941                                                 unmap_underlying_metadata(
 942                                                         inode->i_sb->s_bdev,
 943                                                         map.m_pblk + c);
 944                                 }
 945                         }
 946                         rc = 0;
 947                 }
 948                 if (rc == 0 && total < blen) {
 949                         map.m_lblk = fp->index * blocks_per_page + total;
 950                         map.m_len = blen - total;
 951                         goto cont_map;
 952                 }
 953                 if (rc != 0)
 954                         GOTO(cleanup, rc);
 955
 956                 /* look for next extent */
 957                 fp = NULL;
 958                 blocks += blocks_per_page * clen;
 959         }
 960 cleanup:
 961         return rc;
 962 }
 963 #endif /* HAVE_LDISKFS_MAP_BLOCKS */
 964
 965 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 966                           struct niobuf_local *lnb, int npages)
 967 {
 968         struct osd_thread_info *oti   = osd_oti_get(env);
 969         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 970         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
 971         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
 972         ktime_t start;
 973         ktime_t end;
 974         s64 timediff;
 975         ssize_t                 isize;
 976         __s64                   maxidx;
 977         int                     rc = 0;
 978         int                     i;
 979         int                     cache = 0;
 980
 981         LASSERT(inode);
 982
 983         rc = osd_init_iobuf(osd, iobuf, 0, npages);
 984         if (unlikely(rc != 0))
 985                 RETURN(rc);
 986
 987         isize = i_size_read(inode);
 988         maxidx = ((isize + PAGE_SIZE - 1) >> PAGE_SHIFT) - 1;
 989
 990         if (osd->od_writethrough_cache)
 991                 cache = 1;
 992         if (isize > osd->od_readcache_max_filesize)
 993                 cache = 0;
 994
 995         start = ktime_get();
 996         for (i = 0; i < npages; i++) {
 997
 998                 if (cache == 0)
 999                         generic_error_remove_page(inode->i_mapping,
1000                                                   lnb[i].lnb_page);
1001
1002                 /*
1003                  * till commit the content of the page is undefined
1004                  * we'll set it uptodate once bulk is done. otherwise
1005                  * subsequent reads can access non-stable data
1006                  */
1007                 ClearPageUptodate(lnb[i].lnb_page);
1008
1009                 if (lnb[i].lnb_len == PAGE_SIZE)
1010                         continue;
1011
1012                 if (maxidx >= lnb[i].lnb_page->index) {
1013                         osd_iobuf_add_page(iobuf, lnb[i].lnb_page);
1014                 } else {
1015                         long off;
1016                         char *p = kmap(lnb[i].lnb_page);
1017
1018                         off = lnb[i].lnb_page_offset;
1019                         if (off)
1020                                 memset(p, 0, off);
1021                         off = (lnb[i].lnb_page_offset + lnb[i].lnb_len) &
1022                               ~PAGE_MASK;
1023                         if (off)
1024                                 memset(p + off, 0, PAGE_SIZE - off);
1025                         kunmap(lnb[i].lnb_page);
1026                 }
1027         }
1028         end = ktime_get();
1029         timediff = ktime_us_delta(end, start);
1030         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1031
1032         if (iobuf->dr_npages) {
1033                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1034                                                  iobuf->dr_npages,
1035                                                  iobuf->dr_blocks, 0);
1036                 if (likely(rc == 0)) {
1037                         rc = osd_do_bio(osd, inode, iobuf);
1038                         /* do IO stats for preparation reads */
1039                         osd_fini_iobuf(osd, iobuf);
1040                 }
1041         }
1042         RETURN(rc);
1043 }
1044
1045 struct osd_fextent {
1046         sector_t        start;
1047         sector_t        end;
1048         unsigned int    mapped:1;
1049 };
1050
1051 static int osd_is_mapped(struct dt_object *dt, __u64 offset,
1052                          struct osd_fextent *cached_extent)
1053 {
1054         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1055         sector_t block = offset >> inode->i_blkbits;
1056         sector_t start;
1057         struct fiemap_extent_info fei = { 0 };
1058         struct fiemap_extent fe = { 0 };
1059         mm_segment_t saved_fs;
1060         int rc;
1061
1062         if (block >= cached_extent->start && block < cached_extent->end)
1063                 return cached_extent->mapped;
1064
1065         if (i_size_read(inode) == 0)
1066                 return 0;
1067
1068         /* Beyond EOF, must not be mapped */
1069         if (((i_size_read(inode) - 1) >> inode->i_blkbits) < block)
1070                 return 0;
1071
1072         fei.fi_extents_max = 1;
1073         fei.fi_extents_start = &fe;
1074
1075         saved_fs = get_fs();
1076         set_fs(get_ds());
1077         rc = inode->i_op->fiemap(inode, &fei, offset, FIEMAP_MAX_OFFSET-offset);
1078         set_fs(saved_fs);
1079         if (rc != 0)
1080                 return 0;
1081
1082         start = fe.fe_logical >> inode->i_blkbits;
1083
1084         if (start > block) {
1085                 cached_extent->start = block;
1086                 cached_extent->end = start;
1087                 cached_extent->mapped = 0;
1088         } else {
1089                 cached_extent->start = start;
1090                 cached_extent->end = (fe.fe_logical + fe.fe_length) >>
1091                                       inode->i_blkbits;
1092                 cached_extent->mapped = 1;
1093         }
1094
1095         return cached_extent->mapped;
1096 }
1097
1098 static int osd_declare_write_commit(const struct lu_env *env,
1099                                     struct dt_object *dt,
1100                                     struct niobuf_local *lnb, int npages,
1101                                     struct thandle *handle)
1102 {
1103         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1104         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1105         struct osd_thandle      *oh;
1106         int                      extents = 1;
1107         int                      depth;
1108         int                      i;
1109         int                      newblocks;
1110         int                      rc = 0;
1111         int                      flags = 0;
1112         int                      credits = 0;
1113         bool                     ignore_quota = false;
1114         long long                quota_space = 0;
1115         struct osd_fextent       extent = { 0 };
1116         ENTRY;
1117
1118         LASSERT(handle != NULL);
1119         oh = container_of0(handle, struct osd_thandle, ot_super);
1120         LASSERT(oh->ot_handle == NULL);
1121
1122         newblocks = npages;
1123
1124         /* calculate number of extents (probably better to pass nb) */
1125         for (i = 0; i < npages; i++) {
1126                 if (i && lnb[i].lnb_file_offset !=
1127                     lnb[i - 1].lnb_file_offset + lnb[i - 1].lnb_len)
1128                         extents++;
1129
1130                 if (!osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent))
1131                         quota_space += PAGE_SIZE;
1132
1133                 /* ignore quota for the whole request if any page is from
1134                  * client cache or written by root.
1135                  *
1136                  * XXX once we drop the 1.8 client support, the checking
1137                  * for whether page is from cache can be simplified as:
1138                  * !(lnb[i].flags & OBD_BRW_SYNC)
1139                  *
1140                  * XXX we could handle this on per-lnb basis as done by
1141                  * grant. */
1142                 if ((lnb[i].lnb_flags & OBD_BRW_NOQUOTA) ||
1143                     (lnb[i].lnb_flags & (OBD_BRW_FROM_GRANT | OBD_BRW_SYNC)) ==
1144                     OBD_BRW_FROM_GRANT)
1145                         ignore_quota = true;
1146         }
1147
1148         /*
1149          * each extent can go into new leaf causing a split
1150          * 5 is max tree depth: inode + 4 index blocks
1151          * with blockmaps, depth is 3 at most
1152          */
1153         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
1154                 /*
1155                  * many concurrent threads may grow tree by the time
1156                  * our transaction starts. so, consider 2 is a min depth
1157                  */
1158                 depth = ext_depth(inode);
1159                 depth = max(depth, 1) + 1;
1160                 newblocks += depth;
1161                 credits++; /* inode */
1162                 credits += depth * 2 * extents;
1163         } else {
1164                 depth = 3;
1165                 newblocks += depth;
1166                 credits++; /* inode */
1167                 credits += depth * extents;
1168         }
1169
1170         /* quota space for metadata blocks */
1171         quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
1172
1173         /* quota space should be reported in 1K blocks */
1174         quota_space = toqb(quota_space);
1175
1176         /* each new block can go in different group (bitmap + gd) */
1177
1178         /* we can't dirty more bitmap blocks than exist */
1179         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
1180                 credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
1181         else
1182                 credits += newblocks;
1183
1184         /* we can't dirty more gd blocks than exist */
1185         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
1186                 credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
1187         else
1188                 credits += newblocks;
1189
1190         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1191
1192         /* make sure the over quota flags were not set */
1193         lnb[0].lnb_flags &= ~(OBD_BRW_OVER_USRQUOTA | OBD_BRW_OVER_GRPQUOTA);
1194
1195         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1196                                    quota_space, oh, osd_dt_obj(dt), true,
1197                                    &flags, ignore_quota);
1198
1199         /* we need only to store the overquota flags in the first lnb for
1200          * now, once we support multiple objects BRW, this code needs be
1201          * revised. */
1202         if (flags & QUOTA_FL_OVER_USRQUOTA)
1203                 lnb[0].lnb_flags |= OBD_BRW_OVER_USRQUOTA;
1204         if (flags & QUOTA_FL_OVER_GRPQUOTA)
1205                 lnb[0].lnb_flags |= OBD_BRW_OVER_GRPQUOTA;
1206
1207         RETURN(rc);
1208 }
1209
1210 /* Check if a block is allocated or not */
1211 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
1212                             struct niobuf_local *lnb, int npages,
1213                             struct thandle *thandle)
1214 {
1215         struct osd_thread_info *oti = osd_oti_get(env);
1216         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1217         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1218         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
1219         loff_t isize;
1220         int rc = 0, i;
1221         struct osd_fextent extent = { 0 };
1222
1223         LASSERT(inode);
1224
1225         rc = osd_init_iobuf(osd, iobuf, 1, npages);
1226         if (unlikely(rc != 0))
1227                 RETURN(rc);
1228
1229         isize = i_size_read(inode);
1230         ll_vfs_dq_init(inode);
1231
1232         for (i = 0; i < npages; i++) {
1233                 if (lnb[i].lnb_rc == -ENOSPC &&
1234                     osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent)) {
1235                         /* Allow the write to proceed if overwriting an
1236                          * existing block */
1237                         lnb[i].lnb_rc = 0;
1238                 }
1239
1240                 if (lnb[i].lnb_rc) { /* ENOSPC, network RPC error, etc. */
1241                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
1242                                lnb[i].lnb_rc);
1243                         LASSERT(lnb[i].lnb_page);
1244                         generic_error_remove_page(inode->i_mapping,
1245                                                   lnb[i].lnb_page);
1246                         continue;
1247                 }
1248
1249                 LASSERT(PageLocked(lnb[i].lnb_page));
1250                 LASSERT(!PageWriteback(lnb[i].lnb_page));
1251
1252                 if (lnb[i].lnb_file_offset + lnb[i].lnb_len > isize)
1253                         isize = lnb[i].lnb_file_offset + lnb[i].lnb_len;
1254
1255                 /*
1256                  * Since write and truncate are serialized by oo_sem, even
1257                  * partial-page truncate should not leave dirty pages in the
1258                  * page cache.
1259                  */
1260                 LASSERT(!PageDirty(lnb[i].lnb_page));
1261
1262                 SetPageUptodate(lnb[i].lnb_page);
1263
1264                 osd_iobuf_add_page(iobuf, lnb[i].lnb_page);
1265         }
1266
1267         osd_trans_exec_op(env, thandle, OSD_OT_WRITE);
1268
1269         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
1270                 rc = -ENOSPC;
1271         } else if (iobuf->dr_npages > 0) {
1272                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1273                                                  iobuf->dr_npages,
1274                                                  iobuf->dr_blocks, 1);
1275         } else {
1276                 /* no pages to write, no transno is needed */
1277                 thandle->th_local = 1;
1278         }
1279
1280         if (likely(rc == 0)) {
1281                 spin_lock(&inode->i_lock);
1282                 if (isize > i_size_read(inode)) {
1283                         i_size_write(inode, isize);
1284                         LDISKFS_I(inode)->i_disksize = isize;
1285                         spin_unlock(&inode->i_lock);
1286                         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1287                 } else {
1288                         spin_unlock(&inode->i_lock);
1289                 }
1290
1291                 rc = osd_do_bio(osd, inode, iobuf);
1292                 /* we don't do stats here as in read path because
1293                  * write is async: we'll do this in osd_put_bufs() */
1294         } else {
1295                 osd_fini_iobuf(osd, iobuf);
1296         }
1297
1298         osd_trans_exec_check(env, thandle, OSD_OT_WRITE);
1299
1300         if (unlikely(rc != 0)) {
1301                 /* if write fails, we should drop pages from the cache */
1302                 for (i = 0; i < npages; i++) {
1303                         if (lnb[i].lnb_page == NULL)
1304                                 continue;
1305                         LASSERT(PageLocked(lnb[i].lnb_page));
1306                         generic_error_remove_page(inode->i_mapping,
1307                                                   lnb[i].lnb_page);
1308                 }
1309         }
1310
1311         RETURN(rc);
1312 }
1313
1314 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
1315                          struct niobuf_local *lnb, int npages)
1316 {
1317         struct osd_thread_info *oti = osd_oti_get(env);
1318         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1319         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1320         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1321         int rc = 0, i, cache = 0, cache_hits = 0, cache_misses = 0;
1322         ktime_t start, end;
1323         s64 timediff;
1324         loff_t isize;
1325
1326         LASSERT(inode);
1327
1328         rc = osd_init_iobuf(osd, iobuf, 0, npages);
1329         if (unlikely(rc != 0))
1330                 RETURN(rc);
1331
1332         isize = i_size_read(inode);
1333
1334         if (osd->od_read_cache)
1335                 cache = 1;
1336         if (isize > osd->od_readcache_max_filesize)
1337                 cache = 0;
1338
1339         start = ktime_get();
1340         for (i = 0; i < npages; i++) {
1341
1342                 if (isize <= lnb[i].lnb_file_offset)
1343                         /* If there's no more data, abort early.
1344                          * lnb->lnb_rc == 0, so it's easy to detect later. */
1345                         break;
1346
1347                 if (isize < lnb[i].lnb_file_offset + lnb[i].lnb_len)
1348                         lnb[i].lnb_rc = isize - lnb[i].lnb_file_offset;
1349                 else
1350                         lnb[i].lnb_rc = lnb[i].lnb_len;
1351
1352                 if (PageUptodate(lnb[i].lnb_page)) {
1353                         cache_hits++;
1354                 } else {
1355                         cache_misses++;
1356                         osd_iobuf_add_page(iobuf, lnb[i].lnb_page);
1357                 }
1358
1359                 if (cache == 0)
1360                         generic_error_remove_page(inode->i_mapping,
1361                                                   lnb[i].lnb_page);
1362         }
1363         end = ktime_get();
1364         timediff = ktime_us_delta(end, start);
1365         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1366
1367         if (cache_hits != 0)
1368                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_HIT,
1369                                     cache_hits);
1370         if (cache_misses != 0)
1371                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_MISS,
1372                                     cache_misses);
1373         if (cache_hits + cache_misses != 0)
1374                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS,
1375                                     cache_hits + cache_misses);
1376
1377         if (iobuf->dr_npages) {
1378                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1379                                                  iobuf->dr_npages,
1380                                                  iobuf->dr_blocks, 0);
1381                 rc = osd_do_bio(osd, inode, iobuf);
1382
1383                 /* IO stats will be done in osd_bufs_put() */
1384         }
1385
1386         RETURN(rc);
1387 }
1388
1389 /*
1390  * XXX: Another layering violation for now.
1391  *
1392  * We don't want to use ->f_op->read methods, because generic file write
1393  *
1394  *         - serializes on ->i_sem, and
1395  *
1396  *         - does a lot of extra work like balance_dirty_pages(),
1397  *
1398  * which doesn't work for globally shared files like /last_rcvd.
1399  */
1400 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
1401 {
1402         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
1403
1404         memcpy(buffer, (char *)ei->i_data, buflen);
1405
1406         return  buflen;
1407 }
1408
1409 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
1410 {
1411         struct buffer_head *bh;
1412         unsigned long block;
1413         int osize;
1414         int blocksize;
1415         int csize;
1416         int boffs;
1417
1418         /* prevent reading after eof */
1419         spin_lock(&inode->i_lock);
1420         if (i_size_read(inode) < *offs + size) {
1421                 loff_t diff = i_size_read(inode) - *offs;
1422                 spin_unlock(&inode->i_lock);
1423                 if (diff < 0) {
1424                         CDEBUG(D_EXT2, "size %llu is too short to read @%llu\n",
1425                                i_size_read(inode), *offs);
1426                         return -EBADR;
1427                 } else if (diff == 0) {
1428                         return 0;
1429                 } else {
1430                         size = diff;
1431                 }
1432         } else {
1433                 spin_unlock(&inode->i_lock);
1434         }
1435
1436         blocksize = 1 << inode->i_blkbits;
1437         osize = size;
1438         while (size > 0) {
1439                 block = *offs >> inode->i_blkbits;
1440                 boffs = *offs & (blocksize - 1);
1441                 csize = min(blocksize - boffs, size);
1442                 bh = __ldiskfs_bread(NULL, inode, block, 0);
1443                 if (IS_ERR(bh)) {
1444                         CERROR("%s: can't read %u@%llu on ino %lu: rc = %ld\n",
1445                                LDISKFS_SB(inode->i_sb)->s_es->s_volume_name,
1446                                csize, *offs, inode->i_ino,
1447                                PTR_ERR(bh));
1448                         return PTR_ERR(bh);
1449                 }
1450
1451                 if (bh != NULL) {
1452                         memcpy(buf, bh->b_data + boffs, csize);
1453                         brelse(bh);
1454                 } else {
1455                         memset(buf, 0, csize);
1456                 }
1457
1458                 *offs += csize;
1459                 buf += csize;
1460                 size -= csize;
1461         }
1462         return osize;
1463 }
1464
1465 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
1466                         struct lu_buf *buf, loff_t *pos)
1467 {
1468         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1469         int           rc;
1470
1471         /* Read small symlink from inode body as we need to maintain correct
1472          * on-disk symlinks for ldiskfs.
1473          */
1474         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
1475             (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1476                 rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
1477         else
1478                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
1479
1480         return rc;
1481 }
1482
1483 static inline int osd_extents_enabled(struct super_block *sb,
1484                                       struct inode *inode)
1485 {
1486         if (inode != NULL) {
1487                 if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL)
1488                         return 1;
1489         } else if (LDISKFS_HAS_INCOMPAT_FEATURE(sb,
1490                                 LDISKFS_FEATURE_INCOMPAT_EXTENTS)) {
1491                 return 1;
1492         }
1493         return 0;
1494 }
1495
1496 int osd_calc_bkmap_credits(struct super_block *sb, struct inode *inode,
1497                            const loff_t size, const loff_t pos,
1498                            const int blocks)
1499 {
1500         int credits, bits, bs, i;
1501
1502         bits = sb->s_blocksize_bits;
1503         bs = 1 << bits;
1504
1505         /* legacy blockmap: 3 levels * 3 (bitmap,gd,itself)
1506          * we do not expect blockmaps on the large files,
1507          * so let's shrink it to 2 levels (4GB files) */
1508
1509         /* this is default reservation: 2 levels */
1510         credits = (blocks + 2) * 3;
1511
1512         /* actual offset is unknown, hard to optimize */
1513         if (pos == -1)
1514                 return credits;
1515
1516         /* now check for few specific cases to optimize */
1517         if (pos + size <= LDISKFS_NDIR_BLOCKS * bs) {
1518                 /* no indirects */
1519                 credits = blocks;
1520                 /* allocate if not allocated */
1521                 if (inode == NULL) {
1522                         credits += blocks * 2;
1523                         return credits;
1524                 }
1525                 for (i = (pos >> bits); i < (pos >> bits) + blocks; i++) {
1526                         LASSERT(i < LDISKFS_NDIR_BLOCKS);
1527                         if (LDISKFS_I(inode)->i_data[i] == 0)
1528                                 credits += 2;
1529                 }
1530         } else if (pos + size <= (LDISKFS_NDIR_BLOCKS + 1024) * bs) {
1531                 /* single indirect */
1532                 credits = blocks * 3;
1533                 if (inode == NULL ||
1534                     LDISKFS_I(inode)->i_data[LDISKFS_IND_BLOCK] == 0)
1535                         credits += 3;
1536                 else
1537                         /* The indirect block may be modified. */
1538                         credits += 1;
1539         }
1540
1541         return credits;
1542 }
1543
1544 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
1545                                  const struct lu_buf *buf, loff_t _pos,
1546                                  struct thandle *handle)
1547 {
1548         struct osd_object  *obj  = osd_dt_obj(dt);
1549         struct inode       *inode = obj->oo_inode;
1550         struct super_block *sb = osd_sb(osd_obj2dev(obj));
1551         struct osd_thandle *oh;
1552         int                 rc = 0, est = 0, credits, blocks, allocated = 0;
1553         int                 bits, bs;
1554         int                 depth, size;
1555         loff_t              pos;
1556         ENTRY;
1557
1558         LASSERT(buf != NULL);
1559         LASSERT(handle != NULL);
1560
1561         oh = container_of0(handle, struct osd_thandle, ot_super);
1562         LASSERT(oh->ot_handle == NULL);
1563
1564         size = buf->lb_len;
1565         bits = sb->s_blocksize_bits;
1566         bs = 1 << bits;
1567
1568         if (_pos == -1) {
1569                 /* if this is an append, then we
1570                  * should expect cross-block record */
1571                 pos = 0;
1572         } else {
1573                 pos = _pos;
1574         }
1575
1576         /* blocks to modify */
1577         blocks = ((pos + size + bs - 1) >> bits) - (pos >> bits);
1578         LASSERT(blocks > 0);
1579
1580         if (inode != NULL && _pos != -1) {
1581                 /* object size in blocks */
1582                 est = (i_size_read(inode) + bs - 1) >> bits;
1583                 allocated = inode->i_blocks >> (bits - 9);
1584                 if (pos + size <= i_size_read(inode) && est <= allocated) {
1585                         /* looks like an overwrite, no need to modify tree */
1586                         credits = blocks;
1587                         /* no need to modify i_size */
1588                         goto out;
1589                 }
1590         }
1591
1592         if (osd_extents_enabled(sb, inode)) {
1593                 /*
1594                  * many concurrent threads may grow tree by the time
1595                  * our transaction starts. so, consider 2 is a min depth
1596                  * for every level we may need to allocate a new block
1597                  * and take some entries from the old one. so, 3 blocks
1598                  * to allocate (bitmap, gd, itself) + old block - 4 per
1599                  * level.
1600                  */
1601                 depth = inode != NULL ? ext_depth(inode) : 0;
1602                 depth = max(depth, 1) + 1;
1603                 credits = depth;
1604                 /* if not append, then split may need to modify
1605                  * existing blocks moving entries into the new ones */
1606                 if (_pos == -1)
1607                         credits += depth;
1608                 /* blocks to store data: bitmap,gd,itself */
1609                 credits += blocks * 3;
1610         } else {
1611                 credits = osd_calc_bkmap_credits(sb, inode, size, _pos, blocks);
1612         }
1613         /* if inode is created as part of the transaction,
1614          * then it's counted already by the creation method */
1615         if (inode != NULL)
1616                 credits++;
1617
1618 out:
1619
1620         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1621
1622         /* dt_declare_write() is usually called for system objects, such
1623          * as llog or last_rcvd files. We needn't enforce quota on those
1624          * objects, so always set the lqi_space as 0. */
1625         if (inode != NULL)
1626                 rc = osd_declare_inode_qid(env, i_uid_read(inode),
1627                                            i_gid_read(inode), 0, oh, obj, true,
1628                                            NULL, false);
1629         RETURN(rc);
1630 }
1631
1632 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
1633 {
1634         /* LU-2634: clear the extent format for fast symlink */
1635         ldiskfs_clear_inode_flag(inode, LDISKFS_INODE_EXTENTS);
1636
1637         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
1638         spin_lock(&inode->i_lock);
1639         LDISKFS_I(inode)->i_disksize = buflen;
1640         i_size_write(inode, buflen);
1641         spin_unlock(&inode->i_lock);
1642         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1643
1644         return 0;
1645 }
1646
1647 int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
1648                              int write_NUL, loff_t *offs, handle_t *handle)
1649 {
1650         struct buffer_head *bh        = NULL;
1651         loff_t              offset    = *offs;
1652         loff_t              new_size  = i_size_read(inode);
1653         unsigned long       block;
1654         int                 blocksize = 1 << inode->i_blkbits;
1655         int                 err = 0;
1656         int                 size;
1657         int                 boffs;
1658         int                 dirty_inode = 0;
1659
1660         if (write_NUL) {
1661                 /*
1662                  * long symlink write does not count the NUL terminator in
1663                  * bufsize, we write it, and the inode's file size does not
1664                  * count the NUL terminator as well.
1665                  */
1666                 ((char *)buf)[bufsize] = '\0';
1667                 ++bufsize;
1668         }
1669         while (bufsize > 0) {
1670                 if (bh != NULL)
1671                         brelse(bh);
1672
1673                 block = offset >> inode->i_blkbits;
1674                 boffs = offset & (blocksize - 1);
1675                 size = min(blocksize - boffs, bufsize);
1676                 bh = __ldiskfs_bread(handle, inode, block, 1);
1677                 if (IS_ERR_OR_NULL(bh)) {
1678                         if (bh == NULL) {
1679                                 err = -EIO;
1680                         } else {
1681                                 err = PTR_ERR(bh);
1682                                 bh = NULL;
1683                         }
1684                         CERROR("%s: error reading offset %llu (block %lu): "
1685                                "rc = %d\n",
1686                                inode->i_sb->s_id, offset, block, err);
1687                         break;
1688                 }
1689
1690                 err = ldiskfs_journal_get_write_access(handle, bh);
1691                 if (err) {
1692                         CERROR("journal_get_write_access() returned error %d\n",
1693                                err);
1694                         break;
1695                 }
1696                 LASSERTF(boffs + size <= bh->b_size,
1697                          "boffs %d size %d bh->b_size %lu\n",
1698                          boffs, size, (unsigned long)bh->b_size);
1699                 memcpy(bh->b_data + boffs, buf, size);
1700                 err = ldiskfs_handle_dirty_metadata(handle, NULL, bh);
1701                 if (err)
1702                         break;
1703
1704                 if (offset + size > new_size)
1705                         new_size = offset + size;
1706                 offset += size;
1707                 bufsize -= size;
1708                 buf += size;
1709         }
1710         if (bh)
1711                 brelse(bh);
1712
1713         if (write_NUL)
1714                 --new_size;
1715         /* correct in-core and on-disk sizes */
1716         if (new_size > i_size_read(inode)) {
1717                 spin_lock(&inode->i_lock);
1718                 if (new_size > i_size_read(inode))
1719                         i_size_write(inode, new_size);
1720                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1721                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1722                         dirty_inode = 1;
1723                 }
1724                 spin_unlock(&inode->i_lock);
1725                 if (dirty_inode)
1726                         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1727         }
1728
1729         if (err == 0)
1730                 *offs = offset;
1731         return err;
1732 }
1733
1734 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1735                          const struct lu_buf *buf, loff_t *pos,
1736                          struct thandle *handle, int ignore_quota)
1737 {
1738         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1739         struct osd_thandle      *oh;
1740         ssize_t                 result;
1741         int                     is_link;
1742
1743         LASSERT(dt_object_exists(dt));
1744
1745         LASSERT(handle != NULL);
1746         LASSERT(inode != NULL);
1747         ll_vfs_dq_init(inode);
1748
1749         /* XXX: don't check: one declared chunk can be used many times */
1750         /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
1751
1752         oh = container_of(handle, struct osd_thandle, ot_super);
1753         LASSERT(oh->ot_handle->h_transaction != NULL);
1754         osd_trans_exec_op(env, handle, OSD_OT_WRITE);
1755
1756         /* Write small symlink to inode body as we need to maintain correct
1757          * on-disk symlinks for ldiskfs.
1758          * Note: the buf->lb_buf contains a NUL terminator while buf->lb_len
1759          * does not count it in.
1760          */
1761         is_link = S_ISLNK(dt->do_lu.lo_header->loh_attr);
1762         if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1763                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1764         else
1765                 result = osd_ldiskfs_write_record(inode, buf->lb_buf,
1766                                                   buf->lb_len, is_link, pos,
1767                                                   oh->ot_handle);
1768         if (result == 0)
1769                 result = buf->lb_len;
1770
1771         osd_trans_exec_check(env, handle, OSD_OT_WRITE);
1772
1773         return result;
1774 }
1775
1776 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1777                              __u64 start, __u64 end, struct thandle *th)
1778 {
1779         struct osd_thandle *oh;
1780         struct inode       *inode;
1781         int                 rc;
1782         ENTRY;
1783
1784         LASSERT(th);
1785         oh = container_of(th, struct osd_thandle, ot_super);
1786
1787         /*
1788          * we don't need to reserve credits for whole truncate
1789          * it's not possible as truncate may need to free too many
1790          * blocks and that won't fit a single transaction. instead
1791          * we reserve credits to change i_size and put inode onto
1792          * orphan list. if needed truncate will extend or restart
1793          * transaction
1794          */
1795         osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
1796                              osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
1797
1798         inode = osd_dt_obj(dt)->oo_inode;
1799         LASSERT(inode);
1800
1801         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1802                                    0, oh, osd_dt_obj(dt), true, NULL, false);
1803         RETURN(rc);
1804 }
1805
1806 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1807                      __u64 start, __u64 end, struct thandle *th)
1808 {
1809         struct osd_thandle *oh;
1810         struct osd_object  *obj = osd_dt_obj(dt);
1811         struct inode       *inode = obj->oo_inode;
1812         handle_t           *h;
1813         tid_t               tid;
1814         int                rc = 0, rc2 = 0;
1815         ENTRY;
1816
1817         LASSERT(end == OBD_OBJECT_EOF);
1818         LASSERT(dt_object_exists(dt));
1819         LASSERT(osd_invariant(obj));
1820         LASSERT(inode != NULL);
1821         ll_vfs_dq_init(inode);
1822
1823         LASSERT(th);
1824         oh = container_of(th, struct osd_thandle, ot_super);
1825         LASSERT(oh->ot_handle->h_transaction != NULL);
1826
1827         osd_trans_exec_op(env, th, OSD_OT_PUNCH);
1828
1829         tid = oh->ot_handle->h_transaction->t_tid;
1830
1831         spin_lock(&inode->i_lock);
1832         i_size_write(inode, start);
1833         spin_unlock(&inode->i_lock);
1834         ll_truncate_pagecache(inode, start);
1835 #ifdef HAVE_INODEOPS_TRUNCATE
1836         if (inode->i_op->truncate) {
1837                 inode->i_op->truncate(inode);
1838         } else
1839 #endif
1840                 ldiskfs_truncate(inode);
1841
1842         /*
1843          * For a partial-page truncate, flush the page to disk immediately to
1844          * avoid data corruption during direct disk write.  b=17397
1845          */
1846         if ((start & ~PAGE_MASK) != 0)
1847                 rc = filemap_fdatawrite_range(inode->i_mapping, start, start+1);
1848
1849         h = journal_current_handle();
1850         LASSERT(h != NULL);
1851         LASSERT(h == oh->ot_handle);
1852
1853         /* do not check credits with osd_trans_exec_check() as the truncate
1854          * can restart the transaction internally and we restart the
1855          * transaction in this case */
1856
1857         if (tid != h->h_transaction->t_tid) {
1858                 int credits = oh->ot_credits;
1859                 /*
1860                  * transaction has changed during truncate
1861                  * we need to restart the handle with our credits
1862                  */
1863                 if (h->h_buffer_credits < credits) {
1864                         if (ldiskfs_journal_extend(h, credits))
1865                                 rc2 = ldiskfs_journal_restart(h, credits);
1866                 }
1867         }
1868
1869         RETURN(rc == 0 ? rc2 : rc);
1870 }
1871
1872 static int fiemap_check_ranges(struct inode *inode,
1873                                u64 start, u64 len, u64 *new_len)
1874 {
1875         loff_t maxbytes;
1876
1877         *new_len = len;
1878
1879         if (len == 0)
1880                 return -EINVAL;
1881
1882         if (ldiskfs_test_inode_flag(inode, LDISKFS_INODE_EXTENTS))
1883                 maxbytes = inode->i_sb->s_maxbytes;
1884         else
1885                 maxbytes = LDISKFS_SB(inode->i_sb)->s_bitmap_maxbytes;
1886
1887         if (start > maxbytes)
1888                 return -EFBIG;
1889
1890         /*
1891          * Shrink request scope to what the fs can actually handle.
1892          */
1893         if (len > maxbytes || (maxbytes - len) < start)
1894                 *new_len = maxbytes - start;
1895
1896         return 0;
1897 }
1898
1899 /* So that the fiemap access checks can't overflow on 32 bit machines. */
1900 #define FIEMAP_MAX_EXTENTS     (UINT_MAX / sizeof(struct fiemap_extent))
1901
1902 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
1903                           struct fiemap *fm)
1904 {
1905         struct fiemap_extent_info fieinfo = {0, };
1906         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1907         u64 len;
1908         int rc;
1909
1910
1911         LASSERT(inode);
1912         if (inode->i_op->fiemap == NULL)
1913                 return -EOPNOTSUPP;
1914
1915         if (fm->fm_extent_count > FIEMAP_MAX_EXTENTS)
1916                 return -EINVAL;
1917
1918         rc = fiemap_check_ranges(inode, fm->fm_start, fm->fm_length, &len);
1919         if (rc)
1920                 return rc;
1921
1922         fieinfo.fi_flags = fm->fm_flags;
1923         fieinfo.fi_extents_max = fm->fm_extent_count;
1924         fieinfo.fi_extents_start = fm->fm_extents;
1925
1926         if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
1927                 filemap_write_and_wait(inode->i_mapping);
1928
1929         rc = inode->i_op->fiemap(inode, &fieinfo, fm->fm_start, len);
1930         fm->fm_flags = fieinfo.fi_flags;
1931         fm->fm_mapped_extents = fieinfo.fi_extents_mapped;
1932
1933         return rc;
1934 }
1935
1936 static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
1937                        __u64 start, __u64 end, enum lu_ladvise_type advice)
1938 {
1939         int              rc = 0;
1940         struct inode    *inode = osd_dt_obj(dt)->oo_inode;
1941         ENTRY;
1942
1943         switch (advice) {
1944         case LU_LADVISE_DONTNEED:
1945                 if (end == 0)
1946                         break;
1947                 invalidate_mapping_pages(inode->i_mapping,
1948                                          start >> PAGE_CACHE_SHIFT,
1949                                          (end - 1) >> PAGE_CACHE_SHIFT);
1950                 break;
1951         default:
1952                 rc = -ENOTSUPP;
1953                 break;
1954         }
1955
1956         RETURN(rc);
1957 }
1958
1959 /*
1960  * in some cases we may need declare methods for objects being created
1961  * e.g., when we create symlink
1962  */
1963 const struct dt_body_operations osd_body_ops_new = {
1964         .dbo_declare_write = osd_declare_write,
1965 };
1966
1967 const struct dt_body_operations osd_body_ops = {
1968         .dbo_read                       = osd_read,
1969         .dbo_declare_write              = osd_declare_write,
1970         .dbo_write                      = osd_write,
1971         .dbo_bufs_get                   = osd_bufs_get,
1972         .dbo_bufs_put                   = osd_bufs_put,
1973         .dbo_write_prep                 = osd_write_prep,
1974         .dbo_declare_write_commit       = osd_declare_write_commit,
1975         .dbo_write_commit               = osd_write_commit,
1976         .dbo_read_prep                  = osd_read_prep,
1977         .dbo_declare_punch              = osd_declare_punch,
1978         .dbo_punch                      = osd_punch,
1979         .dbo_fiemap_get                 = osd_fiemap_get,
1980         .dbo_ladvise                    = osd_ladvise,
1981 };