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, 2017, 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 /* prerequisite for linux/xattr.h */
  42 #include <linux/types.h>
  43 /* prerequisite for linux/xattr.h */
  44 #include <linux/fs.h>
  45 #include <linux/mm.h>
  46 #include <linux/pagevec.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 inline bool osd_use_page_cache(struct osd_device *d)
  60 {
  61         /* do not use pagecache if write and read caching are disabled */
  62         if (d->od_writethrough_cache + d->od_read_cache == 0)
  63                 return false;
  64         /* use pagecache by default */
  65         return true;
  66 }
  67
  68 static int __osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,
  69                             int rw, int line, int pages)
  70 {
  71         int blocks, i;
  72
  73         LASSERTF(iobuf->dr_elapsed_valid == 0,
  74                  "iobuf %p, reqs %d, rw %d, line %d\n", iobuf,
  75                  atomic_read(&iobuf->dr_numreqs), iobuf->dr_rw,
  76                  iobuf->dr_init_at);
  77         LASSERT(pages <= PTLRPC_MAX_BRW_PAGES);
  78
  79         init_waitqueue_head(&iobuf->dr_wait);
  80         atomic_set(&iobuf->dr_numreqs, 0);
  81         iobuf->dr_npages = 0;
  82         iobuf->dr_error = 0;
  83         iobuf->dr_dev = d;
  84         iobuf->dr_frags = 0;
  85         iobuf->dr_elapsed = ktime_set(0, 0);
  86         /* must be counted before, so assert */
  87         iobuf->dr_rw = rw;
  88         iobuf->dr_init_at = line;
  89
  90         blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
  91         if (iobuf->dr_bl_buf.lb_len >= blocks * sizeof(iobuf->dr_blocks[0])) {
  92                 LASSERT(iobuf->dr_pg_buf.lb_len >=
  93                         pages * sizeof(iobuf->dr_pages[0]));
  94                 return 0;
  95         }
  96
  97         /* start with 1MB for 4K blocks */
  98         i = 256;
  99         while (i <= PTLRPC_MAX_BRW_PAGES && i < pages)
 100                 i <<= 1;
 101
 102         CDEBUG(D_OTHER, "realloc %u for %u (%u) pages\n",
 103                (unsigned)(pages * sizeof(iobuf->dr_pages[0])), i, pages);
 104         pages = i;
 105         blocks = pages * (PAGE_SIZE >> osd_sb(d)->s_blocksize_bits);
 106         iobuf->dr_max_pages = 0;
 107         CDEBUG(D_OTHER, "realloc %u for %u blocks\n",
 108                (unsigned)(blocks * sizeof(iobuf->dr_blocks[0])), blocks);
 109
 110         lu_buf_realloc(&iobuf->dr_bl_buf, blocks * sizeof(iobuf->dr_blocks[0]));
 111         iobuf->dr_blocks = iobuf->dr_bl_buf.lb_buf;
 112         if (unlikely(iobuf->dr_blocks == NULL))
 113                 return -ENOMEM;
 114
 115         lu_buf_realloc(&iobuf->dr_pg_buf, pages * sizeof(iobuf->dr_pages[0]));
 116         iobuf->dr_pages = iobuf->dr_pg_buf.lb_buf;
 117         if (unlikely(iobuf->dr_pages == NULL))
 118                 return -ENOMEM;
 119
 120         lu_buf_realloc(&iobuf->dr_lnb_buf,
 121                        pages * sizeof(iobuf->dr_lnbs[0]));
 122         iobuf->dr_lnbs = iobuf->dr_lnb_buf.lb_buf;
 123         if (unlikely(iobuf->dr_lnbs == NULL))
 124                 return -ENOMEM;
 125
 126         iobuf->dr_max_pages = pages;
 127
 128         return 0;
 129 }
 130 #define osd_init_iobuf(dev, iobuf, rw, pages) \
 131         __osd_init_iobuf(dev, iobuf, rw, __LINE__, pages)
 132
 133 static void osd_iobuf_add_page(struct osd_iobuf *iobuf,
 134                                struct niobuf_local *lnb)
 135 {
 136         LASSERT(iobuf->dr_npages < iobuf->dr_max_pages);
 137         iobuf->dr_pages[iobuf->dr_npages] = lnb->lnb_page;
 138         iobuf->dr_lnbs[iobuf->dr_npages] = lnb;
 139         iobuf->dr_npages++;
 140 }
 141
 142 void osd_fini_iobuf(struct osd_device *d, struct osd_iobuf *iobuf)
 143 {
 144         int rw = iobuf->dr_rw;
 145
 146         if (iobuf->dr_elapsed_valid) {
 147                 iobuf->dr_elapsed_valid = 0;
 148                 LASSERT(iobuf->dr_dev == d);
 149                 LASSERT(iobuf->dr_frags > 0);
 150                 lprocfs_oh_tally(&d->od_brw_stats.
 151                                  hist[BRW_R_DIO_FRAGS+rw],
 152                                  iobuf->dr_frags);
 153                 lprocfs_oh_tally_log2(&d->od_brw_stats.hist[BRW_R_IO_TIME+rw],
 154                                       ktime_to_ms(iobuf->dr_elapsed));
 155         }
 156 }
 157
 158 #ifdef HAVE_BIO_ENDIO_USES_ONE_ARG
 159 static void dio_complete_routine(struct bio *bio)
 160 {
 161         int error = bio->bi_status;
 162 #else
 163 static void dio_complete_routine(struct bio *bio, int error)
 164 {
 165 #endif
 166         struct osd_iobuf *iobuf = bio->bi_private;
 167         struct bio_vec *bvl;
 168
 169         /* CAVEAT EMPTOR: possibly in IRQ context
 170          * DO NOT record procfs stats here!!! */
 171
 172         if (unlikely(iobuf == NULL)) {
 173                 CERROR("***** bio->bi_private is NULL!  This should never "
 174                        "happen.  Normally, I would crash here, but instead I "
 175                        "will dump the bio contents to the console.  Please "
 176                        "report this to <https://jira.whamcloud.com/> , along "
 177                        "with any interesting messages leading up to this point "
 178                        "(like SCSI errors, perhaps).  Because bi_private is "
 179                        "NULL, I can't wake up the thread that initiated this "
 180                        "IO - you will probably have to reboot this node.\n");
 181                 CERROR("bi_next: %p, bi_flags: %lx, " __stringify(bi_opf)
 182                        ": %x, bi_vcnt: %d, bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, bi_private: %p\n",
 183                        bio->bi_next, (unsigned long)bio->bi_flags,
 184                        (unsigned int)bio->bi_opf, bio->bi_vcnt, bio_idx(bio),
 185                        bio_sectors(bio) << 9, bio->bi_end_io,
 186                        atomic_read(&bio->__bi_cnt),
 187                        bio->bi_private);
 188                 return;
 189         }
 190
 191         /* the check is outside of the cycle for performance reason -bzzz */
 192         if (!bio_data_dir(bio)) {
 193                 DECLARE_BVEC_ITER_ALL(iter_all);
 194
 195                 bio_for_each_segment_all(bvl, bio, iter_all) {
 196                         if (likely(error == 0))
 197                                 SetPageUptodate(bvl_to_page(bvl));
 198                         LASSERT(PageLocked(bvl_to_page(bvl)));
 199                 }
 200                 atomic_dec(&iobuf->dr_dev->od_r_in_flight);
 201         } else {
 202                 atomic_dec(&iobuf->dr_dev->od_w_in_flight);
 203         }
 204
 205         /* any real error is good enough -bzzz */
 206         if (error != 0 && iobuf->dr_error == 0)
 207                 iobuf->dr_error = error;
 208
 209         /*
 210          * set dr_elapsed before dr_numreqs turns to 0, otherwise
 211          * it's possible that service thread will see dr_numreqs
 212          * is zero, but dr_elapsed is not set yet, leading to lost
 213          * data in this processing and an assertion in a subsequent
 214          * call to OSD.
 215          */
 216         if (atomic_read(&iobuf->dr_numreqs) == 1) {
 217                 ktime_t now = ktime_get();
 218
 219                 iobuf->dr_elapsed = ktime_sub(now, iobuf->dr_start_time);
 220                 iobuf->dr_elapsed_valid = 1;
 221         }
 222         if (atomic_dec_and_test(&iobuf->dr_numreqs))
 223                 wake_up(&iobuf->dr_wait);
 224
 225         /* Completed bios used to be chained off iobuf->dr_bios and freed in
 226          * filter_clear_dreq().  It was then possible to exhaust the biovec-256
 227          * mempool when serious on-disk fragmentation was encountered,
 228          * deadlocking the OST.  The bios are now released as soon as complete
 229          * so the pool cannot be exhausted while IOs are competing. bug 10076 */
 230         bio_put(bio);
 231 }
 232
 233 static void record_start_io(struct osd_iobuf *iobuf, int size)
 234 {
 235         struct osd_device    *osd = iobuf->dr_dev;
 236         struct obd_histogram *h = osd->od_brw_stats.hist;
 237
 238         iobuf->dr_frags++;
 239         atomic_inc(&iobuf->dr_numreqs);
 240
 241         if (iobuf->dr_rw == 0) {
 242                 atomic_inc(&osd->od_r_in_flight);
 243                 lprocfs_oh_tally(&h[BRW_R_RPC_HIST],
 244                                  atomic_read(&osd->od_r_in_flight));
 245                 lprocfs_oh_tally_log2(&h[BRW_R_DISK_IOSIZE], size);
 246         } else if (iobuf->dr_rw == 1) {
 247                 atomic_inc(&osd->od_w_in_flight);
 248                 lprocfs_oh_tally(&h[BRW_W_RPC_HIST],
 249                                  atomic_read(&osd->od_w_in_flight));
 250                 lprocfs_oh_tally_log2(&h[BRW_W_DISK_IOSIZE], size);
 251         } else {
 252                 LBUG();
 253         }
 254 }
 255
 256 static void osd_submit_bio(int rw, struct bio *bio)
 257 {
 258         LASSERTF(rw == 0 || rw == 1, "%x\n", rw);
 259 #ifdef HAVE_SUBMIT_BIO_2ARGS
 260         submit_bio(rw ? WRITE : READ, bio);
 261 #else
 262         bio->bi_opf |= rw;
 263         submit_bio(bio);
 264 #endif
 265 }
 266
 267 static int can_be_merged(struct bio *bio, sector_t sector)
 268 {
 269         if (bio == NULL)
 270                 return 0;
 271
 272         return bio_end_sector(bio) == sector ? 1 : 0;
 273 }
 274
 275 #if IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY)
 276 /*
 277  * This function will change the data written, thus it should only be
 278  * used when checking data integrity feature
 279  */
 280 static void bio_integrity_fault_inject(struct bio *bio)
 281 {
 282         struct bio_vec *bvec;
 283         DECLARE_BVEC_ITER_ALL(iter_all);
 284         void *kaddr;
 285         char *addr;
 286
 287         bio_for_each_segment_all(bvec, bio, iter_all) {
 288                 struct page *page = bvec->bv_page;
 289
 290                 kaddr = kmap(page);
 291                 addr = kaddr;
 292                 *addr = ~(*addr);
 293                 kunmap(page);
 294                 break;
 295         }
 296 }
 297
 298 static int bio_dif_compare(__u16 *expected_guard_buf, void *bio_prot_buf,
 299                            unsigned int sectors, int tuple_size)
 300 {
 301         __u16 *expected_guard;
 302         __u16 *bio_guard;
 303         int i;
 304
 305         expected_guard = expected_guard_buf;
 306         for (i = 0; i < sectors; i++) {
 307                 bio_guard = (__u16 *)bio_prot_buf;
 308                 if (*bio_guard != *expected_guard) {
 309                         CERROR("unexpected guard tags on sector %d "
 310                                "expected guard %u, bio guard "
 311                                "%u, sectors %u, tuple size %d\n",
 312                                i, *expected_guard, *bio_guard, sectors,
 313                                tuple_size);
 314                         return -EIO;
 315                 }
 316                 expected_guard++;
 317                 bio_prot_buf += tuple_size;
 318         }
 319         return 0;
 320 }
 321
 322 static int osd_bio_integrity_compare(struct bio *bio, struct block_device *bdev,
 323                                      struct osd_iobuf *iobuf, int index)
 324 {
 325         struct blk_integrity *bi = bdev_get_integrity(bdev);
 326         struct bio_integrity_payload *bip = bio->bi_integrity;
 327         struct niobuf_local *lnb;
 328         unsigned short sector_size = blk_integrity_interval(bi);
 329         void *bio_prot_buf = page_address(bip->bip_vec->bv_page) +
 330                 bip->bip_vec->bv_offset;
 331         struct bio_vec *bv;
 332         sector_t sector = bio_start_sector(bio);
 333         unsigned int sectors, total;
 334         DECLARE_BVEC_ITER_ALL(iter_all);
 335         __u16 *expected_guard;
 336         int rc;
 337
 338         total = 0;
 339         bio_for_each_segment_all(bv, bio, iter_all) {
 340                 lnb = iobuf->dr_lnbs[index];
 341                 expected_guard = lnb->lnb_guards;
 342                 sectors = bv->bv_len / sector_size;
 343                 if (lnb->lnb_guard_rpc) {
 344                         rc = bio_dif_compare(expected_guard, bio_prot_buf,
 345                                              sectors, bi->tuple_size);
 346                         if (rc)
 347                                 return rc;
 348                 }
 349
 350                 sector += sectors;
 351                 bio_prot_buf += sectors * bi->tuple_size;
 352                 total += sectors * bi->tuple_size;
 353                 LASSERT(total <= bip_size(bio->bi_integrity));
 354                 index++;
 355         }
 356         return 0;
 357 }
 358
 359 static int osd_bio_integrity_handle(struct osd_device *osd, struct bio *bio,
 360                                     struct osd_iobuf *iobuf,
 361                                     int start_page_idx, bool fault_inject,
 362                                     bool integrity_enabled)
 363 {
 364         struct super_block *sb = osd_sb(osd);
 365         integrity_gen_fn *generate_fn = NULL;
 366         integrity_vrfy_fn *verify_fn = NULL;
 367         int rc;
 368
 369         ENTRY;
 370
 371         if (!integrity_enabled)
 372                 RETURN(0);
 373
 374         rc = osd_get_integrity_profile(osd, &generate_fn, &verify_fn);
 375         if (rc)
 376                 RETURN(rc);
 377
 378         rc = bio_integrity_prep_fn(bio, generate_fn, verify_fn);
 379         if (rc)
 380                 RETURN(rc);
 381
 382         /* Verify and inject fault only when writing */
 383         if (iobuf->dr_rw == 1) {
 384                 if (unlikely(OBD_FAIL_CHECK(OBD_FAIL_OST_INTEGRITY_CMP))) {
 385                         rc = osd_bio_integrity_compare(bio, sb->s_bdev, iobuf,
 386                                                        start_page_idx);
 387                         if (rc)
 388                                 RETURN(rc);
 389                 }
 390
 391                 if (unlikely(fault_inject))
 392                         bio_integrity_fault_inject(bio);
 393         }
 394
 395         RETURN(0);
 396 }
 397
 398 #ifdef HAVE_BIO_INTEGRITY_PREP_FN
 399 #  ifdef HAVE_BIO_ENDIO_USES_ONE_ARG
 400 static void dio_integrity_complete_routine(struct bio *bio)
 401 #  else
 402 static void dio_integrity_complete_routine(struct bio *bio, int error)
 403 #  endif
 404 {
 405         struct osd_bio_private *bio_private = bio->bi_private;
 406
 407         bio->bi_private = bio_private->obp_iobuf;
 408         osd_dio_complete_routine(bio, error);
 409
 410         OBD_FREE_PTR(bio_private);
 411 }
 412 #endif /* HAVE_BIO_INTEGRITY_PREP_FN */
 413 #else  /* !CONFIG_BLK_DEV_INTEGRITY */
 414 #define osd_bio_integrity_handle(osd, bio, iobuf, start_page_idx, \
 415                                  fault_inject, integrity_enabled) 0
 416 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 417
 418 static int osd_bio_init(struct bio *bio, struct osd_iobuf *iobuf,
 419                         bool integrity_enabled, int start_page_idx,
 420                         struct osd_bio_private **pprivate)
 421 {
 422         ENTRY;
 423
 424         *pprivate = NULL;
 425
 426 #ifdef HAVE_BIO_INTEGRITY_PREP_FN
 427         if (integrity_enabled) {
 428                 struct osd_bio_private *bio_private = NULL;
 429
 430                 OBD_ALLOC_GFP(bio_private, sizeof(*bio_private), GFP_NOIO);
 431                 if (bio_private == NULL)
 432                         RETURN(-ENOMEM);
 433                 bio->bi_end_io = dio_integrity_complete_routine;
 434                 bio->bi_private = bio_private;
 435                 bio_private->obp_start_page_idx = start_page_idx;
 436                 bio_private->obp_iobuf = iobuf;
 437                 *pprivate = bio_private;
 438         } else
 439 #endif
 440         {
 441                 bio->bi_end_io = dio_complete_routine;
 442                 bio->bi_private = iobuf;
 443         }
 444
 445         RETURN(0);
 446 }
 447
 448 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
 449                       struct osd_iobuf *iobuf)
 450 {
 451         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 452         struct page **pages = iobuf->dr_pages;
 453         int npages = iobuf->dr_npages;
 454         sector_t *blocks = iobuf->dr_blocks;
 455         int total_blocks = npages * blocks_per_page;
 456         struct super_block *sb = inode->i_sb;
 457         int sector_bits = sb->s_blocksize_bits - 9;
 458         unsigned int blocksize = sb->s_blocksize;
 459         struct block_device *bdev = sb->s_bdev;
 460         struct osd_bio_private *bio_private = NULL;
 461         struct bio *bio = NULL;
 462         int bio_start_page_idx;
 463         struct page *page;
 464         unsigned int page_offset;
 465         sector_t sector;
 466         int nblocks;
 467         int block_idx;
 468         int page_idx;
 469         int i;
 470         int rc = 0;
 471         bool fault_inject;
 472         bool integrity_enabled;
 473         struct blk_plug plug;
 474         ENTRY;
 475
 476         fault_inject = OBD_FAIL_CHECK(OBD_FAIL_OST_INTEGRITY_FAULT);
 477         LASSERT(iobuf->dr_npages == npages);
 478
 479         integrity_enabled = bdev_integrity_enabled(bdev, iobuf->dr_rw);
 480
 481         osd_brw_stats_update(osd, iobuf);
 482         iobuf->dr_start_time = ktime_get();
 483
 484         blk_start_plug(&plug);
 485         for (page_idx = 0, block_idx = 0;
 486              page_idx < npages;
 487              page_idx++, block_idx += blocks_per_page) {
 488
 489                 page = pages[page_idx];
 490                 LASSERT(block_idx + blocks_per_page <= total_blocks);
 491
 492                 for (i = 0, page_offset = 0;
 493                      i < blocks_per_page;
 494                      i += nblocks, page_offset += blocksize * nblocks) {
 495
 496                         nblocks = 1;
 497
 498                         if (blocks[block_idx + i] == 0) {  /* hole */
 499                                 LASSERTF(iobuf->dr_rw == 0,
 500                                          "page_idx %u, block_idx %u, i %u\n",
 501                                          page_idx, block_idx, i);
 502                                 memset(kmap(page) + page_offset, 0, blocksize);
 503                                 kunmap(page);
 504                                 continue;
 505                         }
 506
 507                         sector = (sector_t)blocks[block_idx + i] << sector_bits;
 508
 509                         /* Additional contiguous file blocks? */
 510                         while (i + nblocks < blocks_per_page &&
 511                                (sector + (nblocks << sector_bits)) ==
 512                                ((sector_t)blocks[block_idx + i + nblocks] <<
 513                                 sector_bits))
 514                                 nblocks++;
 515
 516                         if (bio != NULL &&
 517                             can_be_merged(bio, sector) &&
 518                             bio_add_page(bio, page,
 519                                          blocksize * nblocks, page_offset) != 0)
 520                                 continue;       /* added this frag OK */
 521
 522                         if (bio != NULL) {
 523                                 struct request_queue *q = bio_get_queue(bio);
 524                                 unsigned int bi_size = bio_sectors(bio) << 9;
 525
 526                                 /* Dang! I have to fragment this I/O */
 527                                 CDEBUG(D_INODE,
 528                                        "bio++ sz %d vcnt %d(%d) sectors %d(%d) psg %d(%d)\n",
 529                                        bi_size, bio->bi_vcnt, bio->bi_max_vecs,
 530                                        bio_sectors(bio),
 531                                        queue_max_sectors(q),
 532                                        osd_bio_nr_segs(bio),
 533                                        queue_max_segments(q));
 534                                 rc = osd_bio_integrity_handle(osd, bio,
 535                                         iobuf, bio_start_page_idx,
 536                                         fault_inject, integrity_enabled);
 537                                 if (rc) {
 538                                         bio_put(bio);
 539                                         goto out;
 540                                 }
 541
 542                                 record_start_io(iobuf, bi_size);
 543                                 osd_submit_bio(iobuf->dr_rw, bio);
 544                         }
 545
 546                         bio_start_page_idx = page_idx;
 547                         /* allocate new bio */
 548                         bio = bio_alloc(GFP_NOIO, min(BIO_MAX_PAGES,
 549                                                       (npages - page_idx) *
 550                                                       blocks_per_page));
 551                         if (bio == NULL) {
 552                                 CERROR("Can't allocate bio %u*%u = %u pages\n",
 553                                        (npages - page_idx), blocks_per_page,
 554                                        (npages - page_idx) * blocks_per_page);
 555                                 rc = -ENOMEM;
 556                                 goto out;
 557                         }
 558
 559                         bio_set_dev(bio, bdev);
 560                         bio_set_sector(bio, sector);
 561                         bio->bi_opf = iobuf->dr_rw ? WRITE : READ;
 562                         rc = osd_bio_init(bio, iobuf, integrity_enabled,
 563                                           bio_start_page_idx, &bio_private);
 564                         if (rc) {
 565                                 bio_put(bio);
 566                                 goto out;
 567                         }
 568
 569                         rc = bio_add_page(bio, page,
 570                                           blocksize * nblocks, page_offset);
 571                         LASSERT(rc != 0);
 572                 }
 573         }
 574
 575         if (bio != NULL) {
 576                 rc = osd_bio_integrity_handle(osd, bio, iobuf,
 577                                               bio_start_page_idx,
 578                                               fault_inject,
 579                                               integrity_enabled);
 580                 if (rc) {
 581                         bio_put(bio);
 582                         goto out;
 583                 }
 584
 585                 record_start_io(iobuf, bio_sectors(bio) << 9);
 586                 osd_submit_bio(iobuf->dr_rw, bio);
 587                 rc = 0;
 588         }
 589
 590 out:
 591         blk_finish_plug(&plug);
 592
 593         /* in order to achieve better IO throughput, we don't wait for writes
 594          * completion here. instead we proceed with transaction commit in
 595          * parallel and wait for IO completion once transaction is stopped
 596          * see osd_trans_stop() for more details -bzzz */
 597         if (iobuf->dr_rw == 0 || fault_inject) {
 598                 wait_event(iobuf->dr_wait,
 599                            atomic_read(&iobuf->dr_numreqs) == 0);
 600                 osd_fini_iobuf(osd, iobuf);
 601         }
 602
 603         if (rc == 0) {
 604                 rc = iobuf->dr_error;
 605         } else {
 606                 if (bio_private)
 607                         OBD_FREE_PTR(bio_private);
 608         }
 609
 610         RETURN(rc);
 611 }
 612
 613 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
 614                                    struct niobuf_local *lnb, int maxlnb)
 615 {
 616         int rc = 0;
 617         ENTRY;
 618
 619         *nrpages = 0;
 620
 621         while (len > 0) {
 622                 int poff = offset & (PAGE_SIZE - 1);
 623                 int plen = PAGE_SIZE - poff;
 624
 625                 if (*nrpages >= maxlnb) {
 626                         rc = -EOVERFLOW;
 627                         break;
 628                 }
 629
 630                 if (plen > len)
 631                         plen = len;
 632                 lnb->lnb_file_offset = offset;
 633                 lnb->lnb_page_offset = poff;
 634                 lnb->lnb_len = plen;
 635                 /* lnb->lnb_flags = rnb->rnb_flags; */
 636                 lnb->lnb_flags = 0;
 637                 lnb->lnb_page = NULL;
 638                 lnb->lnb_rc = 0;
 639                 lnb->lnb_guard_rpc = 0;
 640                 lnb->lnb_guard_disk = 0;
 641                 lnb->lnb_locked = 0;
 642
 643                 LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
 644                          (long long) len);
 645                 offset += plen;
 646                 len -= plen;
 647                 lnb++;
 648                 (*nrpages)++;
 649         }
 650
 651         RETURN(rc);
 652 }
 653
 654 static struct page *osd_get_page(const struct lu_env *env, struct dt_object *dt,
 655                                  loff_t offset, gfp_t gfp_mask)
 656 {
 657         struct osd_thread_info *oti = osd_oti_get(env);
 658         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 659         struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
 660         struct page *page;
 661         int cur = oti->oti_dio_pages_used;
 662
 663         LASSERT(inode);
 664
 665         if (osd_use_page_cache(d)) {
 666                 page = find_or_create_page(inode->i_mapping,
 667                                            offset >> PAGE_SHIFT,
 668                                            gfp_mask);
 669
 670                 if (likely(page))
 671                         LASSERT(!test_bit(PG_private_2, &page->flags));
 672                 else
 673                         lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
 674         } else {
 675
 676                 LASSERT(oti->oti_dio_pages);
 677
 678                 if (unlikely(!oti->oti_dio_pages[cur])) {
 679                         LASSERT(cur < PTLRPC_MAX_BRW_PAGES);
 680                         page = alloc_page(gfp_mask);
 681                         if (!page)
 682                                 return NULL;
 683                         oti->oti_dio_pages[cur] = page;
 684                 }
 685
 686                 page = oti->oti_dio_pages[cur];
 687                 LASSERT(!test_bit(PG_private_2, &page->flags));
 688                 set_bit(PG_private_2, &page->flags);
 689                 oti->oti_dio_pages_used++;
 690
 691                 LASSERT(!PageLocked(page));
 692                 lock_page(page);
 693
 694                 LASSERT(!page->mapping);
 695                 LASSERT(!PageWriteback(page));
 696                 ClearPageUptodate(page);
 697
 698                 page->index = offset >> PAGE_SHIFT;
 699         }
 700
 701         return page;
 702 }
 703
 704 /*
 705  * there are following "locks":
 706  * journal_start
 707  * i_mutex
 708  * page lock
 709  *
 710  * osd write path:
 711  *  - lock page(s)
 712  *  - journal_start
 713  *  - truncate_sem
 714  *
 715  * ext4 vmtruncate:
 716  *  - lock pages, unlock
 717  *  - journal_start
 718  *  - lock partial page
 719  *  - i_data_sem
 720  *
 721  */
 722
 723 /**
 724  * Unlock and release pages loaded by osd_bufs_get()
 725  *
 726  * Unlock \a npages pages from \a lnb and drop the refcount on them.
 727  *
 728  * \param env           thread execution environment
 729  * \param dt            dt object undergoing IO (OSD object + methods)
 730  * \param lnb           array of pages undergoing IO
 731  * \param npages        number of pages in \a lnb
 732  *
 733  * \retval 0            always
 734  */
 735 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 736                         struct niobuf_local *lnb, int npages)
 737 {
 738         struct osd_thread_info *oti = osd_oti_get(env);
 739         struct pagevec pvec;
 740         int i;
 741
 742         ll_pagevec_init(&pvec, 0);
 743
 744         for (i = 0; i < npages; i++) {
 745                 struct page *page = lnb[i].lnb_page;
 746
 747                 if (page == NULL)
 748                         continue;
 749
 750                 /* if the page isn't cached, then reset uptodate
 751                  * to prevent reuse */
 752                 if (test_bit(PG_private_2, &page->flags)) {
 753                         clear_bit(PG_private_2, &page->flags);
 754                         ClearPageUptodate(page);
 755                         if (lnb[i].lnb_locked)
 756                                 unlock_page(page);
 757                         oti->oti_dio_pages_used--;
 758                 } else {
 759                         if (lnb[i].lnb_locked)
 760                                 unlock_page(page);
 761                         if (pagevec_add(&pvec, page) == 0)
 762                                 pagevec_release(&pvec);
 763                 }
 764                 dt_object_put(env, dt);
 765
 766                 lnb[i].lnb_page = NULL;
 767         }
 768
 769         LASSERTF(oti->oti_dio_pages_used == 0, "%d\n", oti->oti_dio_pages_used);
 770
 771         /* Release any partial pagevec */
 772         pagevec_release(&pvec);
 773
 774         RETURN(0);
 775 }
 776
 777 /**
 778  * Load and lock pages undergoing IO
 779  *
 780  * Pages as described in the \a lnb array are fetched (from disk or cache)
 781  * and locked for IO by the caller.
 782  *
 783  * DLM locking protects us from write and truncate competing for same region,
 784  * but partial-page truncate can leave dirty pages in the cache for ldiskfs.
 785  * It's possible the writeout on a such a page is in progress when we access
 786  * it. It's also possible that during this writeout we put new (partial) data
 787  * into the page, but won't be able to proceed in filter_commitrw_write().
 788  * Therefore, just wait for writeout completion as it should be rare enough.
 789  *
 790  * \param env           thread execution environment
 791  * \param dt            dt object undergoing IO (OSD object + methods)
 792  * \param pos           byte offset of IO start
 793  * \param len           number of bytes of IO
 794  * \param lnb           array of extents undergoing IO
 795  * \param rw            read or write operation, and other flags
 796  * \param capa          capabilities
 797  *
 798  * \retval pages        (zero or more) loaded successfully
 799  * \retval -ENOMEM      on memory/page allocation error
 800  */
 801 static int osd_bufs_get(const struct lu_env *env, struct dt_object *dt,
 802                         loff_t pos, ssize_t len, struct niobuf_local *lnb,
 803                         int maxlnb, enum dt_bufs_type rw)
 804 {
 805         struct osd_thread_info *oti = osd_oti_get(env);
 806         struct osd_object *obj = osd_dt_obj(dt);
 807         int npages, i, rc = 0;
 808         gfp_t gfp_mask;
 809
 810         LASSERT(obj->oo_inode);
 811
 812         if (!osd_use_page_cache(osd_obj2dev(obj))) {
 813                 if (unlikely(!oti->oti_dio_pages)) {
 814                         OBD_ALLOC(oti->oti_dio_pages,
 815                                   sizeof(struct page *) * PTLRPC_MAX_BRW_PAGES);
 816                         if (!oti->oti_dio_pages)
 817                                 return -ENOMEM;
 818                 }
 819         }
 820
 821         rc = osd_map_remote_to_local(pos, len, &npages, lnb, maxlnb);
 822         if (rc)
 823                 RETURN(rc);
 824
 825         /* this could also try less hard for DT_BUFS_TYPE_READAHEAD pages */
 826         gfp_mask = rw & DT_BUFS_TYPE_LOCAL ? (GFP_NOFS | __GFP_HIGHMEM) :
 827                                              GFP_HIGHUSER;
 828         for (i = 0; i < npages; i++, lnb++) {
 829                 lnb->lnb_page = osd_get_page(env, dt, lnb->lnb_file_offset,
 830                                              gfp_mask);
 831                 if (lnb->lnb_page == NULL)
 832                         GOTO(cleanup, rc = -ENOMEM);
 833
 834                 lnb->lnb_locked = 1;
 835                 wait_on_page_writeback(lnb->lnb_page);
 836                 BUG_ON(PageWriteback(lnb->lnb_page));
 837
 838                 lu_object_get(&dt->do_lu);
 839         }
 840
 841         RETURN(i);
 842
 843 cleanup:
 844         if (i > 0)
 845                 osd_bufs_put(env, dt, lnb - i, i);
 846         return rc;
 847 }
 848
 849 static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
 850                                        int pages, sector_t *blocks,
 851                                        int create)
 852 {
 853         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 854         int rc = 0, i = 0;
 855         struct page *fp = NULL;
 856         int clen = 0;
 857         pgoff_t max_page_index;
 858         handle_t *handle = NULL;
 859
 860         max_page_index = inode->i_sb->s_maxbytes >> PAGE_SHIFT;
 861
 862         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 863                 inode->i_ino, pages, (*page)->index);
 864
 865         if (create) {
 866                 create = LDISKFS_GET_BLOCKS_CREATE;
 867                 handle = ldiskfs_journal_current_handle();
 868                 LASSERT(handle != NULL);
 869                 rc = osd_attach_jinode(inode);
 870                 if (rc)
 871                         return rc;
 872         }
 873         /* pages are sorted already. so, we just have to find
 874          * contig. space and process them properly */
 875         while (i < pages) {
 876                 long blen, total = 0;
 877                 struct ldiskfs_map_blocks map = { 0 };
 878
 879                 if (fp == NULL) { /* start new extent */
 880                         fp = *page++;
 881                         clen = 1;
 882                         if (++i != pages)
 883                                 continue;
 884                 } else if (fp->index + clen == (*page)->index) {
 885                         /* continue the extent */
 886                         page++;
 887                         clen++;
 888                         if (++i != pages)
 889                                 continue;
 890                 }
 891                 if (fp->index + clen >= max_page_index)
 892                         GOTO(cleanup, rc = -EFBIG);
 893                 /* process found extent */
 894                 map.m_lblk = fp->index * blocks_per_page;
 895                 map.m_len = blen = clen * blocks_per_page;
 896 cont_map:
 897                 rc = ldiskfs_map_blocks(handle, inode, &map, create);
 898                 if (rc >= 0) {
 899                         int c = 0;
 900                         for (; total < blen && c < map.m_len; c++, total++) {
 901                                 if (rc == 0) {
 902                                         *(blocks + total) = 0;
 903                                         total++;
 904                                         break;
 905                                 } else {
 906                                         *(blocks + total) = map.m_pblk + c;
 907                                         /* unmap any possible underlying
 908                                          * metadata from the block device
 909                                          * mapping.  bug 6998. */
 910                                         if ((map.m_flags & LDISKFS_MAP_NEW) &&
 911                                             create)
 912                                                 clean_bdev_aliases(
 913                                                         inode->i_sb->s_bdev,
 914                                                         map.m_pblk + c, 1);
 915                                 }
 916                         }
 917                         rc = 0;
 918                 }
 919                 if (rc == 0 && total < blen) {
 920                         map.m_lblk = fp->index * blocks_per_page + total;
 921                         map.m_len = blen - total;
 922                         goto cont_map;
 923                 }
 924                 if (rc != 0)
 925                         GOTO(cleanup, rc);
 926
 927                 /* look for next extent */
 928                 fp = NULL;
 929                 blocks += blocks_per_page * clen;
 930         }
 931 cleanup:
 932         return rc;
 933 }
 934
 935 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 936                           struct niobuf_local *lnb, int npages)
 937 {
 938         struct osd_thread_info *oti   = osd_oti_get(env);
 939         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 940         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
 941         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
 942         ktime_t start;
 943         ktime_t end;
 944         s64 timediff;
 945         ssize_t                 isize;
 946         __s64                   maxidx;
 947         int                     rc = 0;
 948         int                     i;
 949         int                     cache = 0;
 950
 951         LASSERT(inode);
 952
 953         rc = osd_init_iobuf(osd, iobuf, 0, npages);
 954         if (unlikely(rc != 0))
 955                 RETURN(rc);
 956
 957         isize = i_size_read(inode);
 958         maxidx = ((isize + PAGE_SIZE - 1) >> PAGE_SHIFT) - 1;
 959
 960         if (osd->od_writethrough_cache)
 961                 cache = 1;
 962         if (isize > osd->od_readcache_max_filesize)
 963                 cache = 0;
 964
 965         start = ktime_get();
 966         for (i = 0; i < npages; i++) {
 967
 968                 if (cache == 0)
 969                         generic_error_remove_page(inode->i_mapping,
 970                                                   lnb[i].lnb_page);
 971
 972                 /*
 973                  * till commit the content of the page is undefined
 974                  * we'll set it uptodate once bulk is done. otherwise
 975                  * subsequent reads can access non-stable data
 976                  */
 977                 ClearPageUptodate(lnb[i].lnb_page);
 978
 979                 if (lnb[i].lnb_len == PAGE_SIZE)
 980                         continue;
 981
 982                 if (maxidx >= lnb[i].lnb_page->index) {
 983                         osd_iobuf_add_page(iobuf, &lnb[i]);
 984                 } else {
 985                         long off;
 986                         char *p = kmap(lnb[i].lnb_page);
 987
 988                         off = lnb[i].lnb_page_offset;
 989                         if (off)
 990                                 memset(p, 0, off);
 991                         off = (lnb[i].lnb_page_offset + lnb[i].lnb_len) &
 992                               ~PAGE_MASK;
 993                         if (off)
 994                                 memset(p + off, 0, PAGE_SIZE - off);
 995                         kunmap(lnb[i].lnb_page);
 996                 }
 997         }
 998         end = ktime_get();
 999         timediff = ktime_us_delta(end, start);
1000         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1001
1002         if (iobuf->dr_npages) {
1003                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1004                                                  iobuf->dr_npages,
1005                                                  iobuf->dr_blocks, 0);
1006                 if (likely(rc == 0)) {
1007                         rc = osd_do_bio(osd, inode, iobuf);
1008                         /* do IO stats for preparation reads */
1009                         osd_fini_iobuf(osd, iobuf);
1010                 }
1011         }
1012         RETURN(rc);
1013 }
1014
1015 struct osd_fextent {
1016         sector_t        start;
1017         sector_t        end;
1018         unsigned int    mapped:1;
1019 };
1020
1021 static int osd_is_mapped(struct dt_object *dt, __u64 offset,
1022                          struct osd_fextent *cached_extent)
1023 {
1024         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1025         sector_t block = offset >> inode->i_blkbits;
1026         sector_t start;
1027         struct fiemap_extent_info fei = { 0 };
1028         struct fiemap_extent fe = { 0 };
1029         mm_segment_t saved_fs;
1030         int rc;
1031
1032         if (block >= cached_extent->start && block < cached_extent->end)
1033                 return cached_extent->mapped;
1034
1035         if (i_size_read(inode) == 0)
1036                 return 0;
1037
1038         /* Beyond EOF, must not be mapped */
1039         if (((i_size_read(inode) - 1) >> inode->i_blkbits) < block)
1040                 return 0;
1041
1042         fei.fi_extents_max = 1;
1043         fei.fi_extents_start = &fe;
1044
1045         saved_fs = get_fs();
1046         set_fs(KERNEL_DS);
1047         rc = inode->i_op->fiemap(inode, &fei, offset, FIEMAP_MAX_OFFSET-offset);
1048         set_fs(saved_fs);
1049         if (rc != 0)
1050                 return 0;
1051
1052         start = fe.fe_logical >> inode->i_blkbits;
1053
1054         if (start > block) {
1055                 cached_extent->start = block;
1056                 cached_extent->end = start;
1057                 cached_extent->mapped = 0;
1058         } else {
1059                 cached_extent->start = start;
1060                 cached_extent->end = (fe.fe_logical + fe.fe_length) >>
1061                                       inode->i_blkbits;
1062                 cached_extent->mapped = 1;
1063         }
1064
1065         return cached_extent->mapped;
1066 }
1067
1068 static int osd_declare_write_commit(const struct lu_env *env,
1069                                     struct dt_object *dt,
1070                                     struct niobuf_local *lnb, int npages,
1071                                     struct thandle *handle)
1072 {
1073         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1074         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1075         struct osd_thandle      *oh;
1076         int                     extents = 1;
1077         int                     depth;
1078         int                     i;
1079         int                     newblocks;
1080         int                     rc = 0;
1081         int                     flags = 0;
1082         int                     credits = 0;
1083         long long               quota_space = 0;
1084         struct osd_fextent      extent = { 0 };
1085         enum osd_qid_declare_flags declare_flags = OSD_QID_BLK;
1086         ENTRY;
1087
1088         LASSERT(handle != NULL);
1089         oh = container_of0(handle, struct osd_thandle, ot_super);
1090         LASSERT(oh->ot_handle == NULL);
1091
1092         newblocks = npages;
1093
1094         /* calculate number of extents (probably better to pass nb) */
1095         for (i = 0; i < npages; i++) {
1096                 if (i && lnb[i].lnb_file_offset !=
1097                     lnb[i - 1].lnb_file_offset + lnb[i - 1].lnb_len)
1098                         extents++;
1099
1100                 if (osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent))
1101                         lnb[i].lnb_flags |= OBD_BRW_MAPPED;
1102                 else
1103                         quota_space += PAGE_SIZE;
1104
1105                 /* ignore quota for the whole request if any page is from
1106                  * client cache or written by root.
1107                  *
1108                  * XXX once we drop the 1.8 client support, the checking
1109                  * for whether page is from cache can be simplified as:
1110                  * !(lnb[i].flags & OBD_BRW_SYNC)
1111                  *
1112                  * XXX we could handle this on per-lnb basis as done by
1113                  * grant. */
1114                 if ((lnb[i].lnb_flags & OBD_BRW_NOQUOTA) ||
1115                     (lnb[i].lnb_flags & (OBD_BRW_FROM_GRANT | OBD_BRW_SYNC)) ==
1116                     OBD_BRW_FROM_GRANT)
1117                         declare_flags |= OSD_QID_FORCE;
1118         }
1119
1120         /*
1121          * each extent can go into new leaf causing a split
1122          * 5 is max tree depth: inode + 4 index blocks
1123          * with blockmaps, depth is 3 at most
1124          */
1125         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
1126                 /*
1127                  * many concurrent threads may grow tree by the time
1128                  * our transaction starts. so, consider 2 is a min depth
1129                  */
1130                 depth = ext_depth(inode);
1131                 depth = max(depth, 1) + 1;
1132                 newblocks += depth;
1133                 credits++; /* inode */
1134                 credits += depth * 2 * extents;
1135         } else {
1136                 depth = 3;
1137                 newblocks += depth;
1138                 credits++; /* inode */
1139                 credits += depth * extents;
1140         }
1141
1142         /* quota space for metadata blocks */
1143         quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
1144
1145         /* quota space should be reported in 1K blocks */
1146         quota_space = toqb(quota_space);
1147
1148         /* each new block can go in different group (bitmap + gd) */
1149
1150         /* we can't dirty more bitmap blocks than exist */
1151         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
1152                 credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
1153         else
1154                 credits += newblocks;
1155
1156         /* we can't dirty more gd blocks than exist */
1157         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
1158                 credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
1159         else
1160                 credits += newblocks;
1161
1162         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1163
1164         /* make sure the over quota flags were not set */
1165         lnb[0].lnb_flags &= ~OBD_BRW_OVER_ALLQUOTA;
1166
1167         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1168                                    i_projid_read(inode), quota_space, oh,
1169                                    osd_dt_obj(dt), &flags, declare_flags);
1170
1171         /* we need only to store the overquota flags in the first lnb for
1172          * now, once we support multiple objects BRW, this code needs be
1173          * revised. */
1174         if (flags & QUOTA_FL_OVER_USRQUOTA)
1175                 lnb[0].lnb_flags |= OBD_BRW_OVER_USRQUOTA;
1176         if (flags & QUOTA_FL_OVER_GRPQUOTA)
1177                 lnb[0].lnb_flags |= OBD_BRW_OVER_GRPQUOTA;
1178         if (flags & QUOTA_FL_OVER_PRJQUOTA)
1179                 lnb[0].lnb_flags |= OBD_BRW_OVER_PRJQUOTA;
1180
1181         if (rc == 0)
1182                 rc = osd_trunc_lock(osd_dt_obj(dt), oh, true);
1183
1184         RETURN(rc);
1185 }
1186
1187 /* Check if a block is allocated or not */
1188 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
1189                             struct niobuf_local *lnb, int npages,
1190                             struct thandle *thandle)
1191 {
1192         struct osd_thread_info *oti = osd_oti_get(env);
1193         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1194         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1195         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
1196         loff_t isize;
1197         int rc = 0, i;
1198
1199         LASSERT(inode);
1200
1201         rc = osd_init_iobuf(osd, iobuf, 1, npages);
1202         if (unlikely(rc != 0))
1203                 RETURN(rc);
1204
1205         isize = i_size_read(inode);
1206         dquot_initialize(inode);
1207
1208         for (i = 0; i < npages; i++) {
1209                 if (lnb[i].lnb_rc == -ENOSPC &&
1210                     (lnb[i].lnb_flags & OBD_BRW_MAPPED)) {
1211                         /* Allow the write to proceed if overwriting an
1212                          * existing block */
1213                         lnb[i].lnb_rc = 0;
1214                 }
1215
1216                 if (lnb[i].lnb_rc) { /* ENOSPC, network RPC error, etc. */
1217                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
1218                                lnb[i].lnb_rc);
1219                         LASSERT(lnb[i].lnb_page);
1220                         generic_error_remove_page(inode->i_mapping,
1221                                                   lnb[i].lnb_page);
1222                         continue;
1223                 }
1224
1225                 LASSERT(PageLocked(lnb[i].lnb_page));
1226                 LASSERT(!PageWriteback(lnb[i].lnb_page));
1227
1228                 if (lnb[i].lnb_file_offset + lnb[i].lnb_len > isize)
1229                         isize = lnb[i].lnb_file_offset + lnb[i].lnb_len;
1230
1231                 /*
1232                  * Since write and truncate are serialized by oo_sem, even
1233                  * partial-page truncate should not leave dirty pages in the
1234                  * page cache.
1235                  */
1236                 LASSERT(!PageDirty(lnb[i].lnb_page));
1237
1238                 SetPageUptodate(lnb[i].lnb_page);
1239
1240                 osd_iobuf_add_page(iobuf, &lnb[i]);
1241         }
1242
1243         osd_trans_exec_op(env, thandle, OSD_OT_WRITE);
1244
1245         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
1246                 rc = -ENOSPC;
1247         } else if (iobuf->dr_npages > 0) {
1248                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1249                                                  iobuf->dr_npages,
1250                                                  iobuf->dr_blocks, 1);
1251         } else {
1252                 /* no pages to write, no transno is needed */
1253                 thandle->th_local = 1;
1254         }
1255
1256         if (likely(rc == 0)) {
1257                 spin_lock(&inode->i_lock);
1258                 if (isize > i_size_read(inode)) {
1259                         i_size_write(inode, isize);
1260                         LDISKFS_I(inode)->i_disksize = isize;
1261                         spin_unlock(&inode->i_lock);
1262                         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1263                 } else {
1264                         spin_unlock(&inode->i_lock);
1265                 }
1266
1267                 rc = osd_do_bio(osd, inode, iobuf);
1268                 /* we don't do stats here as in read path because
1269                  * write is async: we'll do this in osd_put_bufs() */
1270         } else {
1271                 osd_fini_iobuf(osd, iobuf);
1272         }
1273
1274         osd_trans_exec_check(env, thandle, OSD_OT_WRITE);
1275
1276         if (unlikely(rc != 0)) {
1277                 /* if write fails, we should drop pages from the cache */
1278                 for (i = 0; i < npages; i++) {
1279                         if (lnb[i].lnb_page == NULL)
1280                                 continue;
1281                         LASSERT(PageLocked(lnb[i].lnb_page));
1282                         generic_error_remove_page(inode->i_mapping,
1283                                                   lnb[i].lnb_page);
1284                 }
1285         }
1286
1287         RETURN(rc);
1288 }
1289
1290 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
1291                          struct niobuf_local *lnb, int npages)
1292 {
1293         struct osd_thread_info *oti = osd_oti_get(env);
1294         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1295         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1296         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1297         int rc = 0, i, cache = 0, cache_hits = 0, cache_misses = 0;
1298         ktime_t start, end;
1299         s64 timediff;
1300         loff_t isize;
1301
1302         LASSERT(inode);
1303
1304         rc = osd_init_iobuf(osd, iobuf, 0, npages);
1305         if (unlikely(rc != 0))
1306                 RETURN(rc);
1307
1308         isize = i_size_read(inode);
1309
1310         if (osd->od_read_cache)
1311                 cache = 1;
1312         if (isize > osd->od_readcache_max_filesize)
1313                 cache = 0;
1314
1315         start = ktime_get();
1316         for (i = 0; i < npages; i++) {
1317
1318                 if (isize <= lnb[i].lnb_file_offset)
1319                         /* If there's no more data, abort early.
1320                          * lnb->lnb_rc == 0, so it's easy to detect later. */
1321                         break;
1322
1323                 if (isize < lnb[i].lnb_file_offset + lnb[i].lnb_len)
1324                         lnb[i].lnb_rc = isize - lnb[i].lnb_file_offset;
1325                 else
1326                         lnb[i].lnb_rc = lnb[i].lnb_len;
1327
1328                 /* Bypass disk read if fail_loc is set properly */
1329                 if (OBD_FAIL_CHECK(OBD_FAIL_OST_FAKE_RW))
1330                         SetPageUptodate(lnb[i].lnb_page);
1331
1332                 if (cache == 0)
1333                         generic_error_remove_page(inode->i_mapping,
1334                                                   lnb[i].lnb_page);
1335
1336                 if (PageUptodate(lnb[i].lnb_page)) {
1337                         cache_hits++;
1338                         unlock_page(lnb[i].lnb_page);
1339                 } else {
1340                         cache_misses++;
1341                         osd_iobuf_add_page(iobuf, &lnb[i]);
1342                 }
1343                 /* no need to unlock in osd_bufs_put(), the sooner page is
1344                  * unlocked, the earlier another client can access it.
1345                  * notice real unlock_page() can be called few lines
1346                  * below after osd_do_bio(). lnb is a per-thread, so it's
1347                  * fine to have PG_locked and lnb_locked inconsistent here */
1348                 lnb[i].lnb_locked = 0;
1349         }
1350         end = ktime_get();
1351         timediff = ktime_us_delta(end, start);
1352         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1353
1354         if (cache_hits != 0)
1355                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_HIT,
1356                                     cache_hits);
1357         if (cache_misses != 0)
1358                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_MISS,
1359                                     cache_misses);
1360         if (cache_hits + cache_misses != 0)
1361                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS,
1362                                     cache_hits + cache_misses);
1363
1364         if (iobuf->dr_npages) {
1365                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1366                                                  iobuf->dr_npages,
1367                                                  iobuf->dr_blocks, 0);
1368                 rc = osd_do_bio(osd, inode, iobuf);
1369
1370                 /* IO stats will be done in osd_bufs_put() */
1371
1372                 /* early release to let others read data during the bulk */
1373                 for (i = 0; i < iobuf->dr_npages; i++) {
1374                         LASSERT(PageLocked(iobuf->dr_pages[i]));
1375                         unlock_page(iobuf->dr_pages[i]);
1376                 }
1377         }
1378
1379         RETURN(rc);
1380 }
1381
1382 /*
1383  * XXX: Another layering violation for now.
1384  *
1385  * We don't want to use ->f_op->read methods, because generic file write
1386  *
1387  *         - serializes on ->i_sem, and
1388  *
1389  *         - does a lot of extra work like balance_dirty_pages(),
1390  *
1391  * which doesn't work for globally shared files like /last_rcvd.
1392  */
1393 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
1394 {
1395         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
1396
1397         memcpy(buffer, (char *)ei->i_data, buflen);
1398
1399         return  buflen;
1400 }
1401
1402 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
1403 {
1404         struct buffer_head *bh;
1405         unsigned long block;
1406         int osize;
1407         int blocksize;
1408         int csize;
1409         int boffs;
1410
1411         /* prevent reading after eof */
1412         spin_lock(&inode->i_lock);
1413         if (i_size_read(inode) < *offs + size) {
1414                 loff_t diff = i_size_read(inode) - *offs;
1415                 spin_unlock(&inode->i_lock);
1416                 if (diff < 0) {
1417                         CDEBUG(D_OTHER,
1418                                "size %llu is too short to read @%llu\n",
1419                                i_size_read(inode), *offs);
1420                         return -EBADR;
1421                 } else if (diff == 0) {
1422                         return 0;
1423                 } else {
1424                         size = diff;
1425                 }
1426         } else {
1427                 spin_unlock(&inode->i_lock);
1428         }
1429
1430         blocksize = 1 << inode->i_blkbits;
1431         osize = size;
1432         while (size > 0) {
1433                 block = *offs >> inode->i_blkbits;
1434                 boffs = *offs & (blocksize - 1);
1435                 csize = min(blocksize - boffs, size);
1436                 bh = __ldiskfs_bread(NULL, inode, block, 0);
1437                 if (IS_ERR(bh)) {
1438                         CERROR("%s: can't read %u@%llu on ino %lu: "
1439                                "rc = %ld\n", osd_ino2name(inode),
1440                                csize, *offs, inode->i_ino,
1441                                PTR_ERR(bh));
1442                         return PTR_ERR(bh);
1443                 }
1444
1445                 if (bh != NULL) {
1446                         memcpy(buf, bh->b_data + boffs, csize);
1447                         brelse(bh);
1448                 } else {
1449                         memset(buf, 0, csize);
1450                 }
1451
1452                 *offs += csize;
1453                 buf += csize;
1454                 size -= csize;
1455         }
1456         return osize;
1457 }
1458
1459 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
1460                         struct lu_buf *buf, loff_t *pos)
1461 {
1462         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1463         int           rc;
1464
1465         /* Read small symlink from inode body as we need to maintain correct
1466          * on-disk symlinks for ldiskfs.
1467          */
1468         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
1469             (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1470                 rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
1471         else
1472                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
1473
1474         return rc;
1475 }
1476
1477 static inline int osd_extents_enabled(struct super_block *sb,
1478                                       struct inode *inode)
1479 {
1480         if (inode != NULL) {
1481                 if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL)
1482                         return 1;
1483         } else if (ldiskfs_has_feature_extents(sb)) {
1484                 return 1;
1485         }
1486         return 0;
1487 }
1488
1489 int osd_calc_bkmap_credits(struct super_block *sb, struct inode *inode,
1490                            const loff_t size, const loff_t pos,
1491                            const int blocks)
1492 {
1493         int credits, bits, bs, i;
1494
1495         bits = sb->s_blocksize_bits;
1496         bs = 1 << bits;
1497
1498         /* legacy blockmap: 3 levels * 3 (bitmap,gd,itself)
1499          * we do not expect blockmaps on the large files,
1500          * so let's shrink it to 2 levels (4GB files) */
1501
1502         /* this is default reservation: 2 levels */
1503         credits = (blocks + 2) * 3;
1504
1505         /* actual offset is unknown, hard to optimize */
1506         if (pos == -1)
1507                 return credits;
1508
1509         /* now check for few specific cases to optimize */
1510         if (pos + size <= LDISKFS_NDIR_BLOCKS * bs) {
1511                 /* no indirects */
1512                 credits = blocks;
1513                 /* allocate if not allocated */
1514                 if (inode == NULL) {
1515                         credits += blocks * 2;
1516                         return credits;
1517                 }
1518                 for (i = (pos >> bits); i < (pos >> bits) + blocks; i++) {
1519                         LASSERT(i < LDISKFS_NDIR_BLOCKS);
1520                         if (LDISKFS_I(inode)->i_data[i] == 0)
1521                                 credits += 2;
1522                 }
1523         } else if (pos + size <= (LDISKFS_NDIR_BLOCKS + 1024) * bs) {
1524                 /* single indirect */
1525                 credits = blocks * 3;
1526                 if (inode == NULL ||
1527                     LDISKFS_I(inode)->i_data[LDISKFS_IND_BLOCK] == 0)
1528                         credits += 3;
1529                 else
1530                         /* The indirect block may be modified. */
1531                         credits += 1;
1532         }
1533
1534         return credits;
1535 }
1536
1537 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
1538                                  const struct lu_buf *buf, loff_t _pos,
1539                                  struct thandle *handle)
1540 {
1541         struct osd_object  *obj  = osd_dt_obj(dt);
1542         struct inode       *inode = obj->oo_inode;
1543         struct super_block *sb = osd_sb(osd_obj2dev(obj));
1544         struct osd_thandle *oh;
1545         int                 rc = 0, est = 0, credits, blocks, allocated = 0;
1546         int                 bits, bs;
1547         int                 depth, size;
1548         loff_t              pos;
1549         ENTRY;
1550
1551         LASSERT(buf != NULL);
1552         LASSERT(handle != NULL);
1553
1554         oh = container_of0(handle, struct osd_thandle, ot_super);
1555         LASSERT(oh->ot_handle == NULL);
1556
1557         size = buf->lb_len;
1558         bits = sb->s_blocksize_bits;
1559         bs = 1 << bits;
1560
1561         if (_pos == -1) {
1562                 /* if this is an append, then we
1563                  * should expect cross-block record */
1564                 pos = 0;
1565         } else {
1566                 pos = _pos;
1567         }
1568
1569         /* blocks to modify */
1570         blocks = ((pos + size + bs - 1) >> bits) - (pos >> bits);
1571         LASSERT(blocks > 0);
1572
1573         if (inode != NULL && _pos != -1) {
1574                 /* object size in blocks */
1575                 est = (i_size_read(inode) + bs - 1) >> bits;
1576                 allocated = inode->i_blocks >> (bits - 9);
1577                 if (pos + size <= i_size_read(inode) && est <= allocated) {
1578                         /* looks like an overwrite, no need to modify tree */
1579                         credits = blocks;
1580                         /* no need to modify i_size */
1581                         goto out;
1582                 }
1583         }
1584
1585         if (osd_extents_enabled(sb, inode)) {
1586                 /*
1587                  * many concurrent threads may grow tree by the time
1588                  * our transaction starts. so, consider 2 is a min depth
1589                  * for every level we may need to allocate a new block
1590                  * and take some entries from the old one. so, 3 blocks
1591                  * to allocate (bitmap, gd, itself) + old block - 4 per
1592                  * level.
1593                  */
1594                 depth = inode != NULL ? ext_depth(inode) : 0;
1595                 depth = max(depth, 1) + 1;
1596                 credits = depth;
1597                 /* if not append, then split may need to modify
1598                  * existing blocks moving entries into the new ones */
1599                 if (_pos != -1)
1600                         credits += depth;
1601                 /* blocks to store data: bitmap,gd,itself */
1602                 credits += blocks * 3;
1603         } else {
1604                 credits = osd_calc_bkmap_credits(sb, inode, size, _pos, blocks);
1605         }
1606         /* if inode is created as part of the transaction,
1607          * then it's counted already by the creation method */
1608         if (inode != NULL)
1609                 credits++;
1610
1611 out:
1612
1613         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1614
1615         /* dt_declare_write() is usually called for system objects, such
1616          * as llog or last_rcvd files. We needn't enforce quota on those
1617          * objects, so always set the lqi_space as 0. */
1618         if (inode != NULL)
1619                 rc = osd_declare_inode_qid(env, i_uid_read(inode),
1620                                            i_gid_read(inode),
1621                                            i_projid_read(inode), 0,
1622                                            oh, obj, NULL, OSD_QID_BLK);
1623
1624         if (rc == 0)
1625                 rc = osd_trunc_lock(obj, oh, true);
1626
1627         RETURN(rc);
1628 }
1629
1630 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
1631 {
1632         /* LU-2634: clear the extent format for fast symlink */
1633         ldiskfs_clear_inode_flag(inode, LDISKFS_INODE_EXTENTS);
1634
1635         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
1636         spin_lock(&inode->i_lock);
1637         LDISKFS_I(inode)->i_disksize = buflen;
1638         i_size_write(inode, buflen);
1639         spin_unlock(&inode->i_lock);
1640         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1641
1642         return 0;
1643 }
1644
1645 int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
1646                              int write_NUL, loff_t *offs, handle_t *handle)
1647 {
1648         struct buffer_head *bh        = NULL;
1649         loff_t              offset    = *offs;
1650         loff_t              new_size  = i_size_read(inode);
1651         unsigned long       block;
1652         int                 blocksize = 1 << inode->i_blkbits;
1653         int                 err = 0;
1654         int                 size;
1655         int                 boffs;
1656         int                 dirty_inode = 0;
1657
1658         if (write_NUL) {
1659                 /*
1660                  * long symlink write does not count the NUL terminator in
1661                  * bufsize, we write it, and the inode's file size does not
1662                  * count the NUL terminator as well.
1663                  */
1664                 ((char *)buf)[bufsize] = '\0';
1665                 ++bufsize;
1666         }
1667
1668         while (bufsize > 0) {
1669                 int credits = handle->h_buffer_credits;
1670
1671                 if (bh)
1672                         brelse(bh);
1673
1674                 block = offset >> inode->i_blkbits;
1675                 boffs = offset & (blocksize - 1);
1676                 size = min(blocksize - boffs, bufsize);
1677                 bh = __ldiskfs_bread(handle, inode, block, 1);
1678                 if (IS_ERR_OR_NULL(bh)) {
1679                         if (bh == NULL) {
1680                                 err = -EIO;
1681                         } else {
1682                                 err = PTR_ERR(bh);
1683                                 bh = NULL;
1684                         }
1685
1686                         CERROR("%s: error reading offset %llu (block %lu, "
1687                                "size %d, offs %llu), credits %d/%d: rc = %d\n",
1688                                inode->i_sb->s_id, offset, block, bufsize, *offs,
1689                                credits, handle->h_buffer_credits, err);
1690                         break;
1691                 }
1692
1693                 err = ldiskfs_journal_get_write_access(handle, bh);
1694                 if (err) {
1695                         CERROR("journal_get_write_access() returned error %d\n",
1696                                err);
1697                         break;
1698                 }
1699                 LASSERTF(boffs + size <= bh->b_size,
1700                          "boffs %d size %d bh->b_size %lu\n",
1701                          boffs, size, (unsigned long)bh->b_size);
1702                 memcpy(bh->b_data + boffs, buf, size);
1703                 err = ldiskfs_handle_dirty_metadata(handle, NULL, bh);
1704                 if (err)
1705                         break;
1706
1707                 if (offset + size > new_size)
1708                         new_size = offset + size;
1709                 offset += size;
1710                 bufsize -= size;
1711                 buf += size;
1712         }
1713         if (bh)
1714                 brelse(bh);
1715
1716         if (write_NUL)
1717                 --new_size;
1718         /* correct in-core and on-disk sizes */
1719         if (new_size > i_size_read(inode)) {
1720                 spin_lock(&inode->i_lock);
1721                 if (new_size > i_size_read(inode))
1722                         i_size_write(inode, new_size);
1723                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1724                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1725                         dirty_inode = 1;
1726                 }
1727                 spin_unlock(&inode->i_lock);
1728                 if (dirty_inode)
1729                         ll_dirty_inode(inode, I_DIRTY_DATASYNC);
1730         }
1731
1732         if (err == 0)
1733                 *offs = offset;
1734         return err;
1735 }
1736
1737 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1738                          const struct lu_buf *buf, loff_t *pos,
1739                          struct thandle *handle)
1740 {
1741         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1742         struct osd_thandle      *oh;
1743         ssize_t                 result;
1744         int                     is_link;
1745
1746         LASSERT(dt_object_exists(dt));
1747
1748         LASSERT(handle != NULL);
1749         LASSERT(inode != NULL);
1750         dquot_initialize(inode);
1751
1752         /* XXX: don't check: one declared chunk can be used many times */
1753         /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
1754
1755         oh = container_of(handle, struct osd_thandle, ot_super);
1756         LASSERT(oh->ot_handle->h_transaction != NULL);
1757         osd_trans_exec_op(env, handle, OSD_OT_WRITE);
1758
1759         /* Write small symlink to inode body as we need to maintain correct
1760          * on-disk symlinks for ldiskfs.
1761          * Note: the buf->lb_buf contains a NUL terminator while buf->lb_len
1762          * does not count it in.
1763          */
1764         is_link = S_ISLNK(dt->do_lu.lo_header->loh_attr);
1765         if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1766                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1767         else
1768                 result = osd_ldiskfs_write_record(inode, buf->lb_buf,
1769                                                   buf->lb_len, is_link, pos,
1770                                                   oh->ot_handle);
1771         if (result == 0)
1772                 result = buf->lb_len;
1773
1774         osd_trans_exec_check(env, handle, OSD_OT_WRITE);
1775
1776         return result;
1777 }
1778
1779 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1780                              __u64 start, __u64 end, struct thandle *th)
1781 {
1782         struct osd_thandle *oh;
1783         struct inode       *inode;
1784         int                 rc;
1785         ENTRY;
1786
1787         LASSERT(th);
1788         oh = container_of(th, struct osd_thandle, ot_super);
1789
1790         /*
1791          * we don't need to reserve credits for whole truncate
1792          * it's not possible as truncate may need to free too many
1793          * blocks and that won't fit a single transaction. instead
1794          * we reserve credits to change i_size and put inode onto
1795          * orphan list. if needed truncate will extend or restart
1796          * transaction
1797          */
1798         osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
1799                              osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
1800
1801         inode = osd_dt_obj(dt)->oo_inode;
1802         LASSERT(inode);
1803
1804         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1805                                    i_projid_read(inode), 0, oh, osd_dt_obj(dt),
1806                                    NULL, OSD_QID_BLK);
1807
1808         if (rc == 0)
1809                 rc = osd_trunc_lock(osd_dt_obj(dt), oh, false);
1810
1811         RETURN(rc);
1812 }
1813
1814 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1815                      __u64 start, __u64 end, struct thandle *th)
1816 {
1817         struct osd_object *obj = osd_dt_obj(dt);
1818         struct osd_device *osd = osd_obj2dev(obj);
1819         struct inode *inode = obj->oo_inode;
1820         struct osd_access_lock *al;
1821         struct osd_thandle *oh;
1822         int rc = 0, found = 0;
1823         bool grow = false;
1824         ENTRY;
1825
1826         LASSERT(end == OBD_OBJECT_EOF);
1827         LASSERT(dt_object_exists(dt));
1828         LASSERT(osd_invariant(obj));
1829         LASSERT(inode != NULL);
1830         dquot_initialize(inode);
1831
1832         LASSERT(th);
1833         oh = container_of(th, struct osd_thandle, ot_super);
1834         LASSERT(oh->ot_handle->h_transaction != NULL);
1835
1836         /* we used to skip truncate to current size to
1837          * optimize truncates on OST. with DoM we can
1838          * get attr_set to set specific size (MDS_REINT)
1839          * and then get truncate RPC which essentially
1840          * would be skipped. this is bad.. so, disable
1841          * this optimization on MDS till the client stop
1842          * to sent MDS_REINT (LU-11033) -bzzz */
1843         if (osd->od_is_ost && i_size_read(inode) == start)
1844                 RETURN(0);
1845
1846         osd_trans_exec_op(env, th, OSD_OT_PUNCH);
1847
1848         spin_lock(&inode->i_lock);
1849         if (i_size_read(inode) < start)
1850                 grow = true;
1851         i_size_write(inode, start);
1852         spin_unlock(&inode->i_lock);
1853         ll_truncate_pagecache(inode, start);
1854
1855         /* optimize grow case */
1856         if (grow) {
1857                 osd_execute_truncate(obj);
1858                 GOTO(out, rc);
1859         }
1860
1861         /* add to orphan list to ensure truncate completion
1862          * if this transaction succeed. ldiskfs_truncate()
1863          * will take the inode out of the list */
1864         rc = ldiskfs_orphan_add(oh->ot_handle, inode);
1865         if (rc != 0)
1866                 GOTO(out, rc);
1867
1868         list_for_each_entry(al, &oh->ot_trunc_locks, tl_list) {
1869                 if (obj != al->tl_obj)
1870                         continue;
1871                 LASSERT(al->tl_shared == 0);
1872                 found = 1;
1873                 /* do actual truncate in osd_trans_stop() */
1874                 al->tl_truncate = 1;
1875                 break;
1876         }
1877         LASSERT(found);
1878
1879 out:
1880         RETURN(rc);
1881 }
1882
1883 static int fiemap_check_ranges(struct inode *inode,
1884                                u64 start, u64 len, u64 *new_len)
1885 {
1886         loff_t maxbytes;
1887
1888         *new_len = len;
1889
1890         if (len == 0)
1891                 return -EINVAL;
1892
1893         if (ldiskfs_test_inode_flag(inode, LDISKFS_INODE_EXTENTS))
1894                 maxbytes = inode->i_sb->s_maxbytes;
1895         else
1896                 maxbytes = LDISKFS_SB(inode->i_sb)->s_bitmap_maxbytes;
1897
1898         if (start > maxbytes)
1899                 return -EFBIG;
1900
1901         /*
1902          * Shrink request scope to what the fs can actually handle.
1903          */
1904         if (len > maxbytes || (maxbytes - len) < start)
1905                 *new_len = maxbytes - start;
1906
1907         return 0;
1908 }
1909
1910 /* So that the fiemap access checks can't overflow on 32 bit machines. */
1911 #define FIEMAP_MAX_EXTENTS     (UINT_MAX / sizeof(struct fiemap_extent))
1912
1913 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
1914                           struct fiemap *fm)
1915 {
1916         struct fiemap_extent_info fieinfo = {0, };
1917         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1918         u64 len;
1919         int rc;
1920         mm_segment_t cur_fs;
1921
1922         LASSERT(inode);
1923         if (inode->i_op->fiemap == NULL)
1924                 return -EOPNOTSUPP;
1925
1926         if (fm->fm_extent_count > FIEMAP_MAX_EXTENTS)
1927                 return -EINVAL;
1928
1929         rc = fiemap_check_ranges(inode, fm->fm_start, fm->fm_length, &len);
1930         if (rc)
1931                 return rc;
1932
1933         fieinfo.fi_flags = fm->fm_flags;
1934         fieinfo.fi_extents_max = fm->fm_extent_count;
1935         fieinfo.fi_extents_start = fm->fm_extents;
1936
1937         if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
1938                 filemap_write_and_wait(inode->i_mapping);
1939
1940         /* Save previous value address limit */
1941         cur_fs = get_fs();
1942         /* Set the address limit of the kernel */
1943         set_fs(KERNEL_DS);
1944
1945         rc = inode->i_op->fiemap(inode, &fieinfo, fm->fm_start, len);
1946         fm->fm_flags = fieinfo.fi_flags;
1947         fm->fm_mapped_extents = fieinfo.fi_extents_mapped;
1948
1949         /* Restore the previous address limt */
1950         set_fs(cur_fs);
1951
1952         return rc;
1953 }
1954
1955 static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
1956                        __u64 start, __u64 end, enum lu_ladvise_type advice)
1957 {
1958         int              rc = 0;
1959         struct inode    *inode = osd_dt_obj(dt)->oo_inode;
1960         ENTRY;
1961
1962         switch (advice) {
1963         case LU_LADVISE_DONTNEED:
1964                 if (end == 0)
1965                         break;
1966                 invalidate_mapping_pages(inode->i_mapping,
1967                                          start >> PAGE_SHIFT,
1968                                          (end - 1) >> PAGE_SHIFT);
1969                 break;
1970         default:
1971                 rc = -ENOTSUPP;
1972                 break;
1973         }
1974
1975         RETURN(rc);
1976 }
1977
1978 /*
1979  * in some cases we may need declare methods for objects being created
1980  * e.g., when we create symlink
1981  */
1982 const struct dt_body_operations osd_body_ops_new = {
1983         .dbo_declare_write = osd_declare_write,
1984 };
1985
1986 const struct dt_body_operations osd_body_ops = {
1987         .dbo_read                       = osd_read,
1988         .dbo_declare_write              = osd_declare_write,
1989         .dbo_write                      = osd_write,
1990         .dbo_bufs_get                   = osd_bufs_get,
1991         .dbo_bufs_put                   = osd_bufs_put,
1992         .dbo_write_prep                 = osd_write_prep,
1993         .dbo_declare_write_commit       = osd_declare_write_commit,
1994         .dbo_write_commit               = osd_write_commit,
1995         .dbo_read_prep                  = osd_read_prep,
1996         .dbo_declare_punch              = osd_declare_punch,
1997         .dbo_punch                      = osd_punch,
1998         .dbo_fiemap_get                 = osd_fiemap_get,
1999         .dbo_ladvise                    = osd_ladvise,
2000 };
2001
2002 /**
2003  * Get a truncate lock
2004  *
2005  * In order to take multi-transaction truncate out of main transaction we let
2006  * the caller grab a lock on the object passed. the lock can be shared (for
2007  * writes) and exclusive (for truncate). It's not allowed to mix truncate
2008  * and write in the same transaction handle (do not confuse with big ldiskfs
2009  * transaction containing lots of handles).
2010  * The lock must be taken at declaration.
2011  *
2012  * \param obj           object to lock
2013  * \oh                  transaction
2014  * \shared              shared or exclusive
2015  *
2016  * \retval 0            lock is granted
2017  * \retval -NOMEM       no memory to allocate lock
2018  */
2019 int osd_trunc_lock(struct osd_object *obj, struct osd_thandle *oh, bool shared)
2020 {
2021         struct osd_access_lock *al, *tmp;
2022
2023         LASSERT(obj);
2024         LASSERT(oh);
2025
2026         list_for_each_entry(tmp, &oh->ot_trunc_locks, tl_list) {
2027                 if (tmp->tl_obj != obj)
2028                         continue;
2029                 LASSERT(tmp->tl_shared == shared);
2030                 /* found same lock */
2031                 return 0;
2032         }
2033
2034         OBD_ALLOC_PTR(al);
2035         if (unlikely(al == NULL))
2036                 return -ENOMEM;
2037         al->tl_obj = obj;
2038         al->tl_truncate = false;
2039         if (shared)
2040                 down_read(&obj->oo_ext_idx_sem);
2041         else
2042                 down_write(&obj->oo_ext_idx_sem);
2043         al->tl_shared = shared;
2044
2045         list_add(&al->tl_list, &oh->ot_trunc_locks);
2046
2047         return 0;
2048 }
2049
2050 void osd_trunc_unlock_all(struct list_head *list)
2051 {
2052         struct osd_access_lock *al, *tmp;
2053         list_for_each_entry_safe(al, tmp, list, tl_list) {
2054                 if (al->tl_shared)
2055                         up_read(&al->tl_obj->oo_ext_idx_sem);
2056                 else
2057                         up_write(&al->tl_obj->oo_ext_idx_sem);
2058                 list_del(&al->tl_list);
2059                 OBD_FREE_PTR(al);
2060         }
2061 }
2062
2063 void osd_execute_truncate(struct osd_object *obj)
2064 {
2065         struct osd_device *d = osd_obj2dev(obj);
2066         struct inode *inode = obj->oo_inode;
2067         __u64 size;
2068
2069         /* simulate crash before (in the middle) of delayed truncate */
2070         if (OBD_FAIL_CHECK(OBD_FAIL_OSD_FAIL_AT_TRUNCATE)) {
2071                 struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
2072                 struct ldiskfs_sb_info *sbi = LDISKFS_SB(inode->i_sb);
2073
2074                 mutex_lock(&sbi->s_orphan_lock);
2075                 list_del_init(&ei->i_orphan);
2076                 mutex_unlock(&sbi->s_orphan_lock);
2077                 return;
2078         }
2079
2080         ldiskfs_truncate(inode);
2081
2082         /*
2083          * For a partial-page truncate, flush the page to disk immediately to
2084          * avoid data corruption during direct disk write.  b=17397
2085          */
2086         size = i_size_read(inode);
2087         if ((size & ~PAGE_MASK) == 0)
2088                 return;
2089         if (osd_use_page_cache(d)) {
2090                 filemap_fdatawrite_range(inode->i_mapping, size, size + 1);
2091         } else {
2092                 /* Notice we use "wait" version to ensure I/O is complete */
2093                 filemap_write_and_wait_range(inode->i_mapping, size, size + 1);
2094                 invalidate_mapping_pages(inode->i_mapping, size >> PAGE_SHIFT,
2095                                          size >> PAGE_SHIFT);
2096         }
2097 }
2098
2099 void osd_process_truncates(struct list_head *list)
2100 {
2101         struct osd_access_lock *al;
2102
2103         LASSERT(journal_current_handle() == NULL);
2104
2105         list_for_each_entry(al, list, tl_list) {
2106                 if (al->tl_shared)
2107                         continue;
2108                 if (!al->tl_truncate)
2109                         continue;
2110                 osd_execute_truncate(al->tl_obj);
2111         }
2112 }