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, bool cache)
 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;
 662
 663         LASSERT(inode);
 664
 665         if (cache) {
 666                 page = find_or_create_page(inode->i_mapping,
 667                                            offset >> PAGE_SHIFT, gfp_mask);
 668
 669                 if (likely(page)) {
 670                         LASSERT(!PagePrivate2(page));
 671                         wait_on_page_writeback(page);
 672                 } else {
 673                         lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
 674                 }
 675
 676                 return page;
 677         }
 678
 679         if (inode->i_mapping->nrpages) {
 680                 /* consult with pagecache, but do not create new pages */
 681                 /* this is normally used once */
 682                 page = find_lock_page(inode->i_mapping, offset >> PAGE_SHIFT);
 683                 if (page) {
 684                         wait_on_page_writeback(page);
 685                         return page;
 686                 }
 687         }
 688
 689         LASSERT(oti->oti_dio_pages);
 690         cur = oti->oti_dio_pages_used;
 691         page = oti->oti_dio_pages[cur];
 692
 693         if (unlikely(!page)) {
 694                 LASSERT(cur < PTLRPC_MAX_BRW_PAGES);
 695                 page = alloc_page(gfp_mask);
 696                 if (!page)
 697                         return NULL;
 698                 oti->oti_dio_pages[cur] = page;
 699                 SetPagePrivate2(page);
 700                 lock_page(page);
 701         }
 702
 703         ClearPageUptodate(page);
 704         page->index = offset >> PAGE_SHIFT;
 705         oti->oti_dio_pages_used++;
 706
 707         return page;
 708 }
 709
 710 /*
 711  * there are following "locks":
 712  * journal_start
 713  * i_mutex
 714  * page lock
 715  *
 716  * osd write path:
 717  *  - lock page(s)
 718  *  - journal_start
 719  *  - truncate_sem
 720  *
 721  * ext4 vmtruncate:
 722  *  - lock pages, unlock
 723  *  - journal_start
 724  *  - lock partial page
 725  *  - i_data_sem
 726  *
 727  */
 728
 729 /**
 730  * Unlock and release pages loaded by osd_bufs_get()
 731  *
 732  * Unlock \a npages pages from \a lnb and drop the refcount on them.
 733  *
 734  * \param env           thread execution environment
 735  * \param dt            dt object undergoing IO (OSD object + methods)
 736  * \param lnb           array of pages undergoing IO
 737  * \param npages        number of pages in \a lnb
 738  *
 739  * \retval 0            always
 740  */
 741 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 742                         struct niobuf_local *lnb, int npages)
 743 {
 744         struct osd_thread_info *oti = osd_oti_get(env);
 745         struct pagevec pvec;
 746         int i;
 747
 748         ll_pagevec_init(&pvec, 0);
 749
 750         for (i = 0; i < npages; i++) {
 751                 struct page *page = lnb[i].lnb_page;
 752
 753                 if (page == NULL)
 754                         continue;
 755
 756                 /* if the page isn't cached, then reset uptodate
 757                  * to prevent reuse */
 758                 if (PagePrivate2(page)) {
 759                         oti->oti_dio_pages_used--;
 760                 } else {
 761                         if (lnb[i].lnb_locked)
 762                                 unlock_page(page);
 763                         if (pagevec_add(&pvec, page) == 0)
 764                                 pagevec_release(&pvec);
 765                 }
 766
 767                 lnb[i].lnb_page = NULL;
 768         }
 769
 770         LASSERTF(oti->oti_dio_pages_used == 0, "%d\n", oti->oti_dio_pages_used);
 771
 772         /* Release any partial pagevec */
 773         pagevec_release(&pvec);
 774
 775         RETURN(0);
 776 }
 777
 778 /**
 779  * Load and lock pages undergoing IO
 780  *
 781  * Pages as described in the \a lnb array are fetched (from disk or cache)
 782  * and locked for IO by the caller.
 783  *
 784  * DLM locking protects us from write and truncate competing for same region,
 785  * but partial-page truncate can leave dirty pages in the cache for ldiskfs.
 786  * It's possible the writeout on a such a page is in progress when we access
 787  * it. It's also possible that during this writeout we put new (partial) data
 788  * into the page, but won't be able to proceed in filter_commitrw_write().
 789  * Therefore, just wait for writeout completion as it should be rare enough.
 790  *
 791  * \param env           thread execution environment
 792  * \param dt            dt object undergoing IO (OSD object + methods)
 793  * \param pos           byte offset of IO start
 794  * \param len           number of bytes of IO
 795  * \param lnb           array of extents undergoing IO
 796  * \param rw            read or write operation, and other flags
 797  * \param capa          capabilities
 798  *
 799  * \retval pages        (zero or more) loaded successfully
 800  * \retval -ENOMEM      on memory/page allocation error
 801  */
 802 static int osd_bufs_get(const struct lu_env *env, struct dt_object *dt,
 803                         loff_t pos, ssize_t len, struct niobuf_local *lnb,
 804                         int maxlnb, enum dt_bufs_type rw)
 805 {
 806         struct osd_thread_info *oti = osd_oti_get(env);
 807         struct osd_object *obj = osd_dt_obj(dt);
 808         struct osd_device *osd   = osd_obj2dev(obj);
 809         int npages, i, iosize, rc = 0;
 810         bool cache, write;
 811         loff_t fsize;
 812         gfp_t gfp_mask;
 813
 814         LASSERT(obj->oo_inode);
 815
 816         rc = osd_map_remote_to_local(pos, len, &npages, lnb, maxlnb);
 817         if (rc)
 818                 RETURN(rc);
 819
 820         write = rw & DT_BUFS_TYPE_WRITE;
 821
 822         fsize = lnb[npages - 1].lnb_file_offset + lnb[npages - 1].lnb_len;
 823         iosize = fsize - lnb[0].lnb_file_offset;
 824         fsize = max(fsize, i_size_read(obj->oo_inode));
 825
 826         cache = rw & DT_BUFS_TYPE_READAHEAD;
 827         if (cache)
 828                 goto bypass_checks;
 829
 830         cache = osd_use_page_cache(osd);
 831         while (cache) {
 832                 if (write) {
 833                         if (!osd->od_writethrough_cache) {
 834                                 cache = false;
 835                                 break;
 836                         }
 837                         if (iosize > osd->od_writethrough_max_iosize) {
 838                                 cache = false;
 839                                 break;
 840                         }
 841                 } else {
 842                         if (!osd->od_read_cache) {
 843                                 cache = false;
 844                                 break;
 845                         }
 846                         if (iosize > osd->od_readcache_max_iosize) {
 847                                 cache = false;
 848                                 break;
 849                         }
 850                 }
 851                 /* don't use cache on large files */
 852                 if (osd->od_readcache_max_filesize &&
 853                     fsize > osd->od_readcache_max_filesize)
 854                         cache = false;
 855                 break;
 856         }
 857
 858 bypass_checks:
 859         if (!cache && unlikely(!oti->oti_dio_pages)) {
 860                 OBD_ALLOC(oti->oti_dio_pages,
 861                           sizeof(struct page *) * PTLRPC_MAX_BRW_PAGES);
 862                 if (!oti->oti_dio_pages)
 863                         return -ENOMEM;
 864         }
 865
 866         /* this could also try less hard for DT_BUFS_TYPE_READAHEAD pages */
 867         gfp_mask = rw & DT_BUFS_TYPE_LOCAL ? (GFP_NOFS | __GFP_HIGHMEM) :
 868                                              GFP_HIGHUSER;
 869         for (i = 0; i < npages; i++, lnb++) {
 870                 lnb->lnb_page = osd_get_page(env, dt, lnb->lnb_file_offset,
 871                                              gfp_mask, cache);
 872                 if (lnb->lnb_page == NULL)
 873                         GOTO(cleanup, rc = -ENOMEM);
 874
 875                 lnb->lnb_locked = 1;
 876         }
 877
 878 #if 0
 879         /* XXX: this version doesn't invalidate cached pages, but use them */
 880         if (!cache && write && obj->oo_inode->i_mapping->nrpages) {
 881                 /* do not allow data aliasing, invalidate pagecache */
 882                 /* XXX: can be quite expensive in mixed case */
 883                 invalidate_mapping_pages(obj->oo_inode->i_mapping,
 884                                 lnb[0].lnb_file_offset >> PAGE_SHIFT,
 885                                 lnb[npages - 1].lnb_file_offset >> PAGE_SHIFT);
 886         }
 887 #endif
 888
 889         RETURN(i);
 890
 891 cleanup:
 892         if (i > 0)
 893                 osd_bufs_put(env, dt, lnb - i, i);
 894         return rc;
 895 }
 896
 897 static int osd_ldiskfs_map_inode_pages(struct inode *inode, struct page **page,
 898                                        int pages, sector_t *blocks,
 899                                        int create)
 900 {
 901         int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
 902         int rc = 0, i = 0;
 903         struct page *fp = NULL;
 904         int clen = 0;
 905         pgoff_t max_page_index;
 906         handle_t *handle = NULL;
 907
 908         max_page_index = inode->i_sb->s_maxbytes >> PAGE_SHIFT;
 909
 910         CDEBUG(D_OTHER, "inode %lu: map %d pages from %lu\n",
 911                 inode->i_ino, pages, (*page)->index);
 912
 913         if (create) {
 914                 create = LDISKFS_GET_BLOCKS_CREATE;
 915                 handle = ldiskfs_journal_current_handle();
 916                 LASSERT(handle != NULL);
 917                 rc = osd_attach_jinode(inode);
 918                 if (rc)
 919                         return rc;
 920         }
 921         /* pages are sorted already. so, we just have to find
 922          * contig. space and process them properly */
 923         while (i < pages) {
 924                 long blen, total = 0;
 925                 struct ldiskfs_map_blocks map = { 0 };
 926
 927                 if (fp == NULL) { /* start new extent */
 928                         fp = *page++;
 929                         clen = 1;
 930                         if (++i != pages)
 931                                 continue;
 932                 } else if (fp->index + clen == (*page)->index) {
 933                         /* continue the extent */
 934                         page++;
 935                         clen++;
 936                         if (++i != pages)
 937                                 continue;
 938                 }
 939                 if (fp->index + clen >= max_page_index)
 940                         GOTO(cleanup, rc = -EFBIG);
 941                 /* process found extent */
 942                 map.m_lblk = fp->index * blocks_per_page;
 943                 map.m_len = blen = clen * blocks_per_page;
 944 cont_map:
 945                 rc = ldiskfs_map_blocks(handle, inode, &map, create);
 946                 if (rc >= 0) {
 947                         int c = 0;
 948                         for (; total < blen && c < map.m_len; c++, total++) {
 949                                 if (rc == 0) {
 950                                         *(blocks + total) = 0;
 951                                         total++;
 952                                         break;
 953                                 } else {
 954                                         *(blocks + total) = map.m_pblk + c;
 955                                         /* unmap any possible underlying
 956                                          * metadata from the block device
 957                                          * mapping.  bug 6998. */
 958                                         if ((map.m_flags & LDISKFS_MAP_NEW) &&
 959                                             create)
 960                                                 clean_bdev_aliases(
 961                                                         inode->i_sb->s_bdev,
 962                                                         map.m_pblk + c, 1);
 963                                 }
 964                         }
 965                         rc = 0;
 966                 }
 967                 if (rc == 0 && total < blen) {
 968                         map.m_lblk = fp->index * blocks_per_page + total;
 969                         map.m_len = blen - total;
 970                         goto cont_map;
 971                 }
 972                 if (rc != 0)
 973                         GOTO(cleanup, rc);
 974
 975                 /* look for next extent */
 976                 fp = NULL;
 977                 blocks += blocks_per_page * clen;
 978         }
 979 cleanup:
 980         return rc;
 981 }
 982
 983 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 984                           struct niobuf_local *lnb, int npages)
 985 {
 986         struct osd_thread_info *oti   = osd_oti_get(env);
 987         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 988         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
 989         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
 990         ktime_t start, end;
 991         s64 timediff;
 992         ssize_t isize;
 993         __s64  maxidx;
 994         int i, rc = 0;
 995
 996         LASSERT(inode);
 997
 998         rc = osd_init_iobuf(osd, iobuf, 0, npages);
 999         if (unlikely(rc != 0))
1000                 RETURN(rc);
1001
1002         isize = i_size_read(inode);
1003         maxidx = ((isize + PAGE_SIZE - 1) >> PAGE_SHIFT) - 1;
1004
1005         start = ktime_get();
1006         for (i = 0; i < npages; i++) {
1007
1008                 /*
1009                  * till commit the content of the page is undefined
1010                  * we'll set it uptodate once bulk is done. otherwise
1011                  * subsequent reads can access non-stable data
1012                  */
1013                 ClearPageUptodate(lnb[i].lnb_page);
1014
1015                 if (lnb[i].lnb_len == PAGE_SIZE)
1016                         continue;
1017
1018                 if (maxidx >= lnb[i].lnb_page->index) {
1019                         osd_iobuf_add_page(iobuf, &lnb[i]);
1020                 } else {
1021                         long off;
1022                         char *p = kmap(lnb[i].lnb_page);
1023
1024                         off = lnb[i].lnb_page_offset;
1025                         if (off)
1026                                 memset(p, 0, off);
1027                         off = (lnb[i].lnb_page_offset + lnb[i].lnb_len) &
1028                               ~PAGE_MASK;
1029                         if (off)
1030                                 memset(p + off, 0, PAGE_SIZE - off);
1031                         kunmap(lnb[i].lnb_page);
1032                 }
1033         }
1034         end = ktime_get();
1035         timediff = ktime_us_delta(end, start);
1036         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1037
1038         if (iobuf->dr_npages) {
1039                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1040                                                  iobuf->dr_npages,
1041                                                  iobuf->dr_blocks, 0);
1042                 if (likely(rc == 0)) {
1043                         rc = osd_do_bio(osd, inode, iobuf);
1044                         /* do IO stats for preparation reads */
1045                         osd_fini_iobuf(osd, iobuf);
1046                 }
1047         }
1048         RETURN(rc);
1049 }
1050
1051 struct osd_fextent {
1052         sector_t        start;
1053         sector_t        end;
1054         unsigned int    mapped:1;
1055 };
1056
1057 static int osd_is_mapped(struct dt_object *dt, __u64 offset,
1058                          struct osd_fextent *cached_extent)
1059 {
1060         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1061         sector_t block = offset >> inode->i_blkbits;
1062         sector_t start;
1063         struct fiemap_extent_info fei = { 0 };
1064         struct fiemap_extent fe = { 0 };
1065         mm_segment_t saved_fs;
1066         int rc;
1067
1068         if (block >= cached_extent->start && block < cached_extent->end)
1069                 return cached_extent->mapped;
1070
1071         if (i_size_read(inode) == 0)
1072                 return 0;
1073
1074         /* Beyond EOF, must not be mapped */
1075         if (((i_size_read(inode) - 1) >> inode->i_blkbits) < block)
1076                 return 0;
1077
1078         fei.fi_extents_max = 1;
1079         fei.fi_extents_start = &fe;
1080
1081         saved_fs = get_fs();
1082         set_fs(KERNEL_DS);
1083         rc = inode->i_op->fiemap(inode, &fei, offset, FIEMAP_MAX_OFFSET-offset);
1084         set_fs(saved_fs);
1085         if (rc != 0)
1086                 return 0;
1087
1088         start = fe.fe_logical >> inode->i_blkbits;
1089
1090         if (start > block) {
1091                 cached_extent->start = block;
1092                 cached_extent->end = start;
1093                 cached_extent->mapped = 0;
1094         } else {
1095                 cached_extent->start = start;
1096                 cached_extent->end = (fe.fe_logical + fe.fe_length) >>
1097                                       inode->i_blkbits;
1098                 cached_extent->mapped = 1;
1099         }
1100
1101         return cached_extent->mapped;
1102 }
1103
1104 static int osd_declare_write_commit(const struct lu_env *env,
1105                                     struct dt_object *dt,
1106                                     struct niobuf_local *lnb, int npages,
1107                                     struct thandle *handle)
1108 {
1109         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1110         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1111         struct osd_thandle      *oh;
1112         int                     extents = 1;
1113         int                     depth;
1114         int                     i;
1115         int                     newblocks;
1116         int                     rc = 0;
1117         int                     credits = 0;
1118         long long               quota_space = 0;
1119         struct osd_fextent      extent = { 0 };
1120         enum osd_quota_local_flags local_flags = 0;
1121         enum osd_qid_declare_flags declare_flags = OSD_QID_BLK;
1122         ENTRY;
1123
1124         LASSERT(handle != NULL);
1125         oh = container_of0(handle, struct osd_thandle, ot_super);
1126         LASSERT(oh->ot_handle == NULL);
1127
1128         newblocks = npages;
1129
1130         /* calculate number of extents (probably better to pass nb) */
1131         for (i = 0; i < npages; i++) {
1132                 if (i && lnb[i].lnb_file_offset !=
1133                     lnb[i - 1].lnb_file_offset + lnb[i - 1].lnb_len)
1134                         extents++;
1135
1136                 if (osd_is_mapped(dt, lnb[i].lnb_file_offset, &extent))
1137                         lnb[i].lnb_flags |= OBD_BRW_MAPPED;
1138                 else
1139                         quota_space += PAGE_SIZE;
1140
1141                 /* ignore quota for the whole request if any page is from
1142                  * client cache or written by root.
1143                  *
1144                  * XXX once we drop the 1.8 client support, the checking
1145                  * for whether page is from cache can be simplified as:
1146                  * !(lnb[i].flags & OBD_BRW_SYNC)
1147                  *
1148                  * XXX we could handle this on per-lnb basis as done by
1149                  * grant. */
1150                 if ((lnb[i].lnb_flags & OBD_BRW_NOQUOTA) ||
1151                     (lnb[i].lnb_flags & (OBD_BRW_FROM_GRANT | OBD_BRW_SYNC)) ==
1152                     OBD_BRW_FROM_GRANT)
1153                         declare_flags |= OSD_QID_FORCE;
1154         }
1155
1156         /*
1157          * each extent can go into new leaf causing a split
1158          * 5 is max tree depth: inode + 4 index blocks
1159          * with blockmaps, depth is 3 at most
1160          */
1161         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
1162                 /*
1163                  * many concurrent threads may grow tree by the time
1164                  * our transaction starts. so, consider 2 is a min depth
1165                  */
1166                 depth = ext_depth(inode);
1167                 depth = max(depth, 1) + 1;
1168                 newblocks += depth;
1169                 credits++; /* inode */
1170                 credits += depth * 2 * extents;
1171         } else {
1172                 depth = 3;
1173                 newblocks += depth;
1174                 credits++; /* inode */
1175                 credits += depth * extents;
1176         }
1177
1178         /* quota space for metadata blocks */
1179         quota_space += depth * extents * LDISKFS_BLOCK_SIZE(osd_sb(osd));
1180
1181         /* quota space should be reported in 1K blocks */
1182         quota_space = toqb(quota_space);
1183
1184         /* each new block can go in different group (bitmap + gd) */
1185
1186         /* we can't dirty more bitmap blocks than exist */
1187         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
1188                 credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
1189         else
1190                 credits += newblocks;
1191
1192         /* we can't dirty more gd blocks than exist */
1193         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
1194                 credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
1195         else
1196                 credits += newblocks;
1197
1198         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1199
1200         /* make sure the over quota flags were not set */
1201         lnb[0].lnb_flags &= ~OBD_BRW_OVER_ALLQUOTA;
1202
1203         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1204                                    i_projid_read(inode), quota_space, oh,
1205                                    osd_dt_obj(dt), &local_flags, declare_flags);
1206
1207         /* we need only to store the overquota flags in the first lnb for
1208          * now, once we support multiple objects BRW, this code needs be
1209          * revised. */
1210         if (local_flags & QUOTA_FL_OVER_USRQUOTA)
1211                 lnb[0].lnb_flags |= OBD_BRW_OVER_USRQUOTA;
1212         if (local_flags & QUOTA_FL_OVER_GRPQUOTA)
1213                 lnb[0].lnb_flags |= OBD_BRW_OVER_GRPQUOTA;
1214         if (local_flags & QUOTA_FL_OVER_PRJQUOTA)
1215                 lnb[0].lnb_flags |= OBD_BRW_OVER_PRJQUOTA;
1216
1217         if (rc == 0)
1218                 rc = osd_trunc_lock(osd_dt_obj(dt), oh, true);
1219
1220         RETURN(rc);
1221 }
1222
1223 /* Check if a block is allocated or not */
1224 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
1225                             struct niobuf_local *lnb, int npages,
1226                             struct thandle *thandle)
1227 {
1228         struct osd_thread_info *oti = osd_oti_get(env);
1229         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1230         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1231         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
1232         loff_t isize;
1233         int rc = 0, i;
1234
1235         LASSERT(inode);
1236
1237         rc = osd_init_iobuf(osd, iobuf, 1, npages);
1238         if (unlikely(rc != 0))
1239                 RETURN(rc);
1240
1241         isize = i_size_read(inode);
1242         dquot_initialize(inode);
1243
1244         for (i = 0; i < npages; i++) {
1245                 if (lnb[i].lnb_rc == -ENOSPC &&
1246                     (lnb[i].lnb_flags & OBD_BRW_MAPPED)) {
1247                         /* Allow the write to proceed if overwriting an
1248                          * existing block */
1249                         lnb[i].lnb_rc = 0;
1250                 }
1251
1252                 if (lnb[i].lnb_rc) { /* ENOSPC, network RPC error, etc. */
1253                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
1254                                lnb[i].lnb_rc);
1255                         LASSERT(lnb[i].lnb_page);
1256                         generic_error_remove_page(inode->i_mapping,
1257                                                   lnb[i].lnb_page);
1258                         continue;
1259                 }
1260
1261                 LASSERT(PageLocked(lnb[i].lnb_page));
1262                 LASSERT(!PageWriteback(lnb[i].lnb_page));
1263
1264                 if (lnb[i].lnb_file_offset + lnb[i].lnb_len > isize)
1265                         isize = lnb[i].lnb_file_offset + lnb[i].lnb_len;
1266
1267                 /*
1268                  * Since write and truncate are serialized by oo_sem, even
1269                  * partial-page truncate should not leave dirty pages in the
1270                  * page cache.
1271                  */
1272                 LASSERT(!PageDirty(lnb[i].lnb_page));
1273
1274                 SetPageUptodate(lnb[i].lnb_page);
1275
1276                 osd_iobuf_add_page(iobuf, &lnb[i]);
1277         }
1278
1279         osd_trans_exec_op(env, thandle, OSD_OT_WRITE);
1280
1281         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
1282                 rc = -ENOSPC;
1283         } else if (iobuf->dr_npages > 0) {
1284                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1285                                                  iobuf->dr_npages,
1286                                                  iobuf->dr_blocks, 1);
1287         } else {
1288                 /* no pages to write, no transno is needed */
1289                 thandle->th_local = 1;
1290         }
1291
1292         if (likely(rc == 0)) {
1293                 spin_lock(&inode->i_lock);
1294                 if (isize > i_size_read(inode)) {
1295                         i_size_write(inode, isize);
1296                         LDISKFS_I(inode)->i_disksize = isize;
1297                         spin_unlock(&inode->i_lock);
1298                         osd_dirty_inode(inode, I_DIRTY_DATASYNC);
1299                 } else {
1300                         spin_unlock(&inode->i_lock);
1301                 }
1302
1303                 rc = osd_do_bio(osd, inode, iobuf);
1304                 /* we don't do stats here as in read path because
1305                  * write is async: we'll do this in osd_put_bufs() */
1306         } else {
1307                 osd_fini_iobuf(osd, iobuf);
1308         }
1309
1310         osd_trans_exec_check(env, thandle, OSD_OT_WRITE);
1311
1312         if (unlikely(rc != 0)) {
1313                 /* if write fails, we should drop pages from the cache */
1314                 for (i = 0; i < npages; i++) {
1315                         if (lnb[i].lnb_page == NULL)
1316                                 continue;
1317                         if (!PagePrivate2(lnb[i].lnb_page)) {
1318                                 LASSERT(PageLocked(lnb[i].lnb_page));
1319                                 generic_error_remove_page(inode->i_mapping,
1320                                                           lnb[i].lnb_page);
1321                         }
1322                 }
1323         }
1324
1325         RETURN(rc);
1326 }
1327
1328 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
1329                          struct niobuf_local *lnb, int npages)
1330 {
1331         struct osd_thread_info *oti = osd_oti_get(env);
1332         struct osd_iobuf *iobuf = &oti->oti_iobuf;
1333         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1334         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1335         int rc = 0, i, cache_hits = 0, cache_misses = 0;
1336         ktime_t start, end;
1337         s64 timediff;
1338         loff_t isize;
1339
1340         LASSERT(inode);
1341
1342         rc = osd_init_iobuf(osd, iobuf, 0, npages);
1343         if (unlikely(rc != 0))
1344                 RETURN(rc);
1345
1346         isize = i_size_read(inode);
1347
1348         start = ktime_get();
1349         for (i = 0; i < npages; i++) {
1350
1351                 if (isize <= lnb[i].lnb_file_offset)
1352                         /* If there's no more data, abort early.
1353                          * lnb->lnb_rc == 0, so it's easy to detect later. */
1354                         break;
1355
1356                 /* instead of looking if we go beyong isize, send complete
1357                  * pages all the time
1358                  */
1359                 lnb[i].lnb_rc = lnb[i].lnb_len;
1360
1361                 /* Bypass disk read if fail_loc is set properly */
1362                 if (OBD_FAIL_CHECK(OBD_FAIL_OST_FAKE_RW))
1363                         SetPageUptodate(lnb[i].lnb_page);
1364
1365                 if (PageUptodate(lnb[i].lnb_page)) {
1366                         cache_hits++;
1367                         unlock_page(lnb[i].lnb_page);
1368                 } else {
1369                         cache_misses++;
1370                         osd_iobuf_add_page(iobuf, &lnb[i]);
1371                 }
1372                 /* no need to unlock in osd_bufs_put(), the sooner page is
1373                  * unlocked, the earlier another client can access it.
1374                  * notice real unlock_page() can be called few lines
1375                  * below after osd_do_bio(). lnb is a per-thread, so it's
1376                  * fine to have PG_locked and lnb_locked inconsistent here */
1377                 lnb[i].lnb_locked = 0;
1378         }
1379         end = ktime_get();
1380         timediff = ktime_us_delta(end, start);
1381         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
1382
1383         if (cache_hits != 0)
1384                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_HIT,
1385                                     cache_hits);
1386         if (cache_misses != 0)
1387                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_MISS,
1388                                     cache_misses);
1389         if (cache_hits + cache_misses != 0)
1390                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS,
1391                                     cache_hits + cache_misses);
1392
1393         if (iobuf->dr_npages) {
1394                 rc = osd_ldiskfs_map_inode_pages(inode, iobuf->dr_pages,
1395                                                  iobuf->dr_npages,
1396                                                  iobuf->dr_blocks, 0);
1397                 rc = osd_do_bio(osd, inode, iobuf);
1398
1399                 /* IO stats will be done in osd_bufs_put() */
1400
1401                 /* early release to let others read data during the bulk */
1402                 for (i = 0; i < iobuf->dr_npages; i++) {
1403                         LASSERT(PageLocked(iobuf->dr_pages[i]));
1404                         if (!PagePrivate2(iobuf->dr_pages[i]))
1405                                 unlock_page(iobuf->dr_pages[i]);
1406                 }
1407         }
1408
1409         RETURN(rc);
1410 }
1411
1412 /*
1413  * XXX: Another layering violation for now.
1414  *
1415  * We don't want to use ->f_op->read methods, because generic file write
1416  *
1417  *         - serializes on ->i_sem, and
1418  *
1419  *         - does a lot of extra work like balance_dirty_pages(),
1420  *
1421  * which doesn't work for globally shared files like /last_rcvd.
1422  */
1423 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
1424 {
1425         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
1426
1427         memcpy(buffer, (char *)ei->i_data, buflen);
1428
1429         return  buflen;
1430 }
1431
1432 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
1433 {
1434         struct buffer_head *bh;
1435         unsigned long block;
1436         int osize;
1437         int blocksize;
1438         int csize;
1439         int boffs;
1440
1441         /* prevent reading after eof */
1442         spin_lock(&inode->i_lock);
1443         if (i_size_read(inode) < *offs + size) {
1444                 loff_t diff = i_size_read(inode) - *offs;
1445                 spin_unlock(&inode->i_lock);
1446                 if (diff < 0) {
1447                         CDEBUG(D_OTHER,
1448                                "size %llu is too short to read @%llu\n",
1449                                i_size_read(inode), *offs);
1450                         return -EBADR;
1451                 } else if (diff == 0) {
1452                         return 0;
1453                 } else {
1454                         size = diff;
1455                 }
1456         } else {
1457                 spin_unlock(&inode->i_lock);
1458         }
1459
1460         blocksize = 1 << inode->i_blkbits;
1461         osize = size;
1462         while (size > 0) {
1463                 block = *offs >> inode->i_blkbits;
1464                 boffs = *offs & (blocksize - 1);
1465                 csize = min(blocksize - boffs, size);
1466                 bh = __ldiskfs_bread(NULL, inode, block, 0);
1467                 if (IS_ERR(bh)) {
1468                         CERROR("%s: can't read %u@%llu on ino %lu: "
1469                                "rc = %ld\n", osd_ino2name(inode),
1470                                csize, *offs, inode->i_ino,
1471                                PTR_ERR(bh));
1472                         return PTR_ERR(bh);
1473                 }
1474
1475                 if (bh != NULL) {
1476                         memcpy(buf, bh->b_data + boffs, csize);
1477                         brelse(bh);
1478                 } else {
1479                         memset(buf, 0, csize);
1480                 }
1481
1482                 *offs += csize;
1483                 buf += csize;
1484                 size -= csize;
1485         }
1486         return osize;
1487 }
1488
1489 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
1490                         struct lu_buf *buf, loff_t *pos)
1491 {
1492         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1493         int rc;
1494
1495         /* Read small symlink from inode body as we need to maintain correct
1496          * on-disk symlinks for ldiskfs.
1497          */
1498         if (S_ISLNK(dt->do_lu.lo_header->loh_attr)) {
1499                 loff_t size = i_size_read(inode);
1500
1501                 if (buf->lb_len < size)
1502                         return -EOVERFLOW;
1503
1504                 if (size < sizeof(LDISKFS_I(inode)->i_data))
1505                         rc = osd_ldiskfs_readlink(inode, buf->lb_buf, size);
1506                 else
1507                         rc = osd_ldiskfs_read(inode, buf->lb_buf, size, pos);
1508         } else {
1509                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
1510         }
1511
1512         return rc;
1513 }
1514
1515 static inline int osd_extents_enabled(struct super_block *sb,
1516                                       struct inode *inode)
1517 {
1518         if (inode != NULL) {
1519                 if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL)
1520                         return 1;
1521         } else if (ldiskfs_has_feature_extents(sb)) {
1522                 return 1;
1523         }
1524         return 0;
1525 }
1526
1527 int osd_calc_bkmap_credits(struct super_block *sb, struct inode *inode,
1528                            const loff_t size, const loff_t pos,
1529                            const int blocks)
1530 {
1531         int credits, bits, bs, i;
1532
1533         bits = sb->s_blocksize_bits;
1534         bs = 1 << bits;
1535
1536         /* legacy blockmap: 3 levels * 3 (bitmap,gd,itself)
1537          * we do not expect blockmaps on the large files,
1538          * so let's shrink it to 2 levels (4GB files) */
1539
1540         /* this is default reservation: 2 levels */
1541         credits = (blocks + 2) * 3;
1542
1543         /* actual offset is unknown, hard to optimize */
1544         if (pos == -1)
1545                 return credits;
1546
1547         /* now check for few specific cases to optimize */
1548         if (pos + size <= LDISKFS_NDIR_BLOCKS * bs) {
1549                 /* no indirects */
1550                 credits = blocks;
1551                 /* allocate if not allocated */
1552                 if (inode == NULL) {
1553                         credits += blocks * 2;
1554                         return credits;
1555                 }
1556                 for (i = (pos >> bits); i < (pos >> bits) + blocks; i++) {
1557                         LASSERT(i < LDISKFS_NDIR_BLOCKS);
1558                         if (LDISKFS_I(inode)->i_data[i] == 0)
1559                                 credits += 2;
1560                 }
1561         } else if (pos + size <= (LDISKFS_NDIR_BLOCKS + 1024) * bs) {
1562                 /* single indirect */
1563                 credits = blocks * 3;
1564                 if (inode == NULL ||
1565                     LDISKFS_I(inode)->i_data[LDISKFS_IND_BLOCK] == 0)
1566                         credits += 3;
1567                 else
1568                         /* The indirect block may be modified. */
1569                         credits += 1;
1570         }
1571
1572         return credits;
1573 }
1574
1575 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
1576                                  const struct lu_buf *buf, loff_t _pos,
1577                                  struct thandle *handle)
1578 {
1579         struct osd_object  *obj  = osd_dt_obj(dt);
1580         struct inode       *inode = obj->oo_inode;
1581         struct super_block *sb = osd_sb(osd_obj2dev(obj));
1582         struct osd_thandle *oh;
1583         int                 rc = 0, est = 0, credits, blocks, allocated = 0;
1584         int                 bits, bs;
1585         int                 depth, size;
1586         loff_t              pos;
1587         ENTRY;
1588
1589         LASSERT(buf != NULL);
1590         LASSERT(handle != NULL);
1591
1592         oh = container_of0(handle, struct osd_thandle, ot_super);
1593         LASSERT(oh->ot_handle == NULL);
1594
1595         size = buf->lb_len;
1596         bits = sb->s_blocksize_bits;
1597         bs = 1 << bits;
1598
1599         if (_pos == -1) {
1600                 /* if this is an append, then we
1601                  * should expect cross-block record */
1602                 pos = 0;
1603         } else {
1604                 pos = _pos;
1605         }
1606
1607         /* blocks to modify */
1608         blocks = ((pos + size + bs - 1) >> bits) - (pos >> bits);
1609         LASSERT(blocks > 0);
1610
1611         if (inode != NULL && _pos != -1) {
1612                 /* object size in blocks */
1613                 est = (i_size_read(inode) + bs - 1) >> bits;
1614                 allocated = inode->i_blocks >> (bits - 9);
1615                 if (pos + size <= i_size_read(inode) && est <= allocated) {
1616                         /* looks like an overwrite, no need to modify tree */
1617                         credits = blocks;
1618                         /* no need to modify i_size */
1619                         goto out;
1620                 }
1621         }
1622
1623         if (osd_extents_enabled(sb, inode)) {
1624                 /*
1625                  * many concurrent threads may grow tree by the time
1626                  * our transaction starts. so, consider 2 is a min depth
1627                  * for every level we may need to allocate a new block
1628                  * and take some entries from the old one. so, 3 blocks
1629                  * to allocate (bitmap, gd, itself) + old block - 4 per
1630                  * level.
1631                  */
1632                 depth = inode != NULL ? ext_depth(inode) : 0;
1633                 depth = max(depth, 1) + 1;
1634                 credits = depth;
1635                 /* if not append, then split may need to modify
1636                  * existing blocks moving entries into the new ones */
1637                 if (_pos != -1)
1638                         credits += depth;
1639                 /* blocks to store data: bitmap,gd,itself */
1640                 credits += blocks * 3;
1641         } else {
1642                 credits = osd_calc_bkmap_credits(sb, inode, size, _pos, blocks);
1643         }
1644         /* if inode is created as part of the transaction,
1645          * then it's counted already by the creation method */
1646         if (inode != NULL)
1647                 credits++;
1648
1649 out:
1650
1651         osd_trans_declare_op(env, oh, OSD_OT_WRITE, credits);
1652
1653         /* dt_declare_write() is usually called for system objects, such
1654          * as llog or last_rcvd files. We needn't enforce quota on those
1655          * objects, so always set the lqi_space as 0. */
1656         if (inode != NULL)
1657                 rc = osd_declare_inode_qid(env, i_uid_read(inode),
1658                                            i_gid_read(inode),
1659                                            i_projid_read(inode), 0,
1660                                            oh, obj, NULL, OSD_QID_BLK);
1661
1662         if (rc == 0)
1663                 rc = osd_trunc_lock(obj, oh, true);
1664
1665         RETURN(rc);
1666 }
1667
1668 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
1669 {
1670         /* LU-2634: clear the extent format for fast symlink */
1671         ldiskfs_clear_inode_flag(inode, LDISKFS_INODE_EXTENTS);
1672
1673         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
1674         spin_lock(&inode->i_lock);
1675         LDISKFS_I(inode)->i_disksize = buflen;
1676         i_size_write(inode, buflen);
1677         spin_unlock(&inode->i_lock);
1678         osd_dirty_inode(inode, I_DIRTY_DATASYNC);
1679
1680         return 0;
1681 }
1682
1683 static int osd_ldiskfs_write_record(struct dt_object *dt, void *buf,
1684                                     int bufsize, int write_NUL, loff_t *offs,
1685                                     handle_t *handle)
1686 {
1687         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1688         struct buffer_head *bh        = NULL;
1689         loff_t              offset    = *offs;
1690         loff_t              new_size  = i_size_read(inode);
1691         unsigned long       block;
1692         int                 blocksize = 1 << inode->i_blkbits;
1693         int                 err = 0;
1694         int                 size;
1695         int                 boffs;
1696         int                 dirty_inode = 0;
1697         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
1698         bool create, sparse, sync = false;
1699
1700         if (write_NUL) {
1701                 /*
1702                  * long symlink write does not count the NUL terminator in
1703                  * bufsize, we write it, and the inode's file size does not
1704                  * count the NUL terminator as well.
1705                  */
1706                 ((char *)buf)[bufsize] = '\0';
1707                 ++bufsize;
1708         }
1709
1710         /* sparse checking is racy, but sparse is very rare case, leave as is */
1711         sparse = (new_size > 0 && (inode->i_blocks >> (inode->i_blkbits - 9)) <
1712                   ((new_size - 1) >> inode->i_blkbits) + 1);
1713
1714         while (bufsize > 0) {
1715                 int credits = handle->h_buffer_credits;
1716                 unsigned long last_block = (new_size == 0) ? 0 :
1717                                            (new_size - 1) >> inode->i_blkbits;
1718
1719                 if (bh)
1720                         brelse(bh);
1721
1722                 block = offset >> inode->i_blkbits;
1723                 boffs = offset & (blocksize - 1);
1724                 size = min(blocksize - boffs, bufsize);
1725                 sync = (block > last_block || new_size == 0 || sparse);
1726
1727                 if (sync)
1728                         down(&ei->i_append_sem);
1729
1730                 bh = __ldiskfs_bread(handle, inode, block, 0);
1731
1732                 if (unlikely(IS_ERR_OR_NULL(bh) && !sync))
1733                         CWARN("%s: adding bh without locking off %llu (block %lu, "
1734                               "size %d, offs %llu)\n", inode->i_sb->s_id,
1735                               offset, block, bufsize, *offs);
1736
1737                 if (IS_ERR_OR_NULL(bh)) {
1738                         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
1739                         int flags = LDISKFS_GET_BLOCKS_CREATE;
1740
1741                         /* while the file system is being mounted, avoid
1742                          * preallocation otherwise mount can take a long
1743                          * time as mballoc cache is cold.
1744                          * XXX: this is a workaround until we have a proper
1745                          *      fix in mballoc
1746                          * XXX: works with extent-based files only */
1747                         if (!osd->od_cl_seq)
1748                                 flags |= LDISKFS_GET_BLOCKS_NO_NORMALIZE;
1749                         bh = __ldiskfs_bread(handle, inode, block, flags);
1750                         create = true;
1751                 } else {
1752                         if (sync) {
1753                                 up(&ei->i_append_sem);
1754                                 sync = false;
1755                         }
1756                         create = false;
1757                 }
1758                 if (IS_ERR_OR_NULL(bh)) {
1759                         if (bh == NULL) {
1760                                 err = -EIO;
1761                         } else {
1762                                 err = PTR_ERR(bh);
1763                                 bh = NULL;
1764                         }
1765
1766                         CERROR("%s: error reading offset %llu (block %lu, "
1767                                "size %d, offs %llu), credits %d/%d: rc = %d\n",
1768                                inode->i_sb->s_id, offset, block, bufsize, *offs,
1769                                credits, handle->h_buffer_credits, err);
1770                         break;
1771                 }
1772
1773                 err = ldiskfs_journal_get_write_access(handle, bh);
1774                 if (err) {
1775                         CERROR("journal_get_write_access() returned error %d\n",
1776                                err);
1777                         break;
1778                 }
1779                 LASSERTF(boffs + size <= bh->b_size,
1780                          "boffs %d size %d bh->b_size %lu\n",
1781                          boffs, size, (unsigned long)bh->b_size);
1782                 if (create) {
1783                         memset(bh->b_data, 0, bh->b_size);
1784                         if (sync) {
1785                                 up(&ei->i_append_sem);
1786                                 sync = false;
1787                         }
1788                 }
1789                 memcpy(bh->b_data + boffs, buf, size);
1790                 err = ldiskfs_handle_dirty_metadata(handle, NULL, bh);
1791                 if (err)
1792                         break;
1793
1794                 if (offset + size > new_size)
1795                         new_size = offset + size;
1796                 offset += size;
1797                 bufsize -= size;
1798                 buf += size;
1799         }
1800         if (sync)
1801                 up(&ei->i_append_sem);
1802
1803         if (bh)
1804                 brelse(bh);
1805
1806         if (write_NUL)
1807                 --new_size;
1808         /* correct in-core and on-disk sizes */
1809         if (new_size > i_size_read(inode)) {
1810                 spin_lock(&inode->i_lock);
1811                 if (new_size > i_size_read(inode))
1812                         i_size_write(inode, new_size);
1813                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1814                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1815                         dirty_inode = 1;
1816                 }
1817                 spin_unlock(&inode->i_lock);
1818                 if (dirty_inode)
1819                         osd_dirty_inode(inode, I_DIRTY_DATASYNC);
1820         }
1821
1822         if (err == 0)
1823                 *offs = offset;
1824         return err;
1825 }
1826
1827 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1828                          const struct lu_buf *buf, loff_t *pos,
1829                          struct thandle *handle)
1830 {
1831         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
1832         struct osd_thandle      *oh;
1833         ssize_t                 result;
1834         int                     is_link;
1835
1836         LASSERT(dt_object_exists(dt));
1837
1838         LASSERT(handle != NULL);
1839         LASSERT(inode != NULL);
1840         dquot_initialize(inode);
1841
1842         /* XXX: don't check: one declared chunk can be used many times */
1843         /* osd_trans_exec_op(env, handle, OSD_OT_WRITE); */
1844
1845         oh = container_of(handle, struct osd_thandle, ot_super);
1846         LASSERT(oh->ot_handle->h_transaction != NULL);
1847         osd_trans_exec_op(env, handle, OSD_OT_WRITE);
1848
1849         /* Write small symlink to inode body as we need to maintain correct
1850          * on-disk symlinks for ldiskfs.
1851          * Note: the buf->lb_buf contains a NUL terminator while buf->lb_len
1852          * does not count it in.
1853          */
1854         is_link = S_ISLNK(dt->do_lu.lo_header->loh_attr);
1855         if (is_link && (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1856                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1857         else
1858                 result = osd_ldiskfs_write_record(dt, buf->lb_buf, buf->lb_len,
1859                                                   is_link, pos, oh->ot_handle);
1860         if (result == 0)
1861                 result = buf->lb_len;
1862
1863         osd_trans_exec_check(env, handle, OSD_OT_WRITE);
1864
1865         return result;
1866 }
1867
1868 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1869                              __u64 start, __u64 end, struct thandle *th)
1870 {
1871         struct osd_thandle *oh;
1872         struct inode       *inode;
1873         int                 rc;
1874         ENTRY;
1875
1876         LASSERT(th);
1877         oh = container_of(th, struct osd_thandle, ot_super);
1878
1879         /*
1880          * we don't need to reserve credits for whole truncate
1881          * it's not possible as truncate may need to free too many
1882          * blocks and that won't fit a single transaction. instead
1883          * we reserve credits to change i_size and put inode onto
1884          * orphan list. if needed truncate will extend or restart
1885          * transaction
1886          */
1887         osd_trans_declare_op(env, oh, OSD_OT_PUNCH,
1888                              osd_dto_credits_noquota[DTO_ATTR_SET_BASE] + 3);
1889
1890         inode = osd_dt_obj(dt)->oo_inode;
1891         LASSERT(inode);
1892
1893         rc = osd_declare_inode_qid(env, i_uid_read(inode), i_gid_read(inode),
1894                                    i_projid_read(inode), 0, oh, osd_dt_obj(dt),
1895                                    NULL, OSD_QID_BLK);
1896
1897         if (rc == 0)
1898                 rc = osd_trunc_lock(osd_dt_obj(dt), oh, false);
1899
1900         RETURN(rc);
1901 }
1902
1903 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1904                      __u64 start, __u64 end, struct thandle *th)
1905 {
1906         struct osd_object *obj = osd_dt_obj(dt);
1907         struct osd_device *osd = osd_obj2dev(obj);
1908         struct inode *inode = obj->oo_inode;
1909         struct osd_access_lock *al;
1910         struct osd_thandle *oh;
1911         int rc = 0, found = 0;
1912         bool grow = false;
1913         ENTRY;
1914
1915         LASSERT(end == OBD_OBJECT_EOF);
1916         LASSERT(dt_object_exists(dt));
1917         LASSERT(osd_invariant(obj));
1918         LASSERT(inode != NULL);
1919         dquot_initialize(inode);
1920
1921         LASSERT(th);
1922         oh = container_of(th, struct osd_thandle, ot_super);
1923         LASSERT(oh->ot_handle->h_transaction != NULL);
1924
1925         /* we used to skip truncate to current size to
1926          * optimize truncates on OST. with DoM we can
1927          * get attr_set to set specific size (MDS_REINT)
1928          * and then get truncate RPC which essentially
1929          * would be skipped. this is bad.. so, disable
1930          * this optimization on MDS till the client stop
1931          * to sent MDS_REINT (LU-11033) -bzzz */
1932         if (osd->od_is_ost && i_size_read(inode) == start)
1933                 RETURN(0);
1934
1935         osd_trans_exec_op(env, th, OSD_OT_PUNCH);
1936
1937         spin_lock(&inode->i_lock);
1938         if (i_size_read(inode) < start)
1939                 grow = true;
1940         i_size_write(inode, start);
1941         spin_unlock(&inode->i_lock);
1942         ll_truncate_pagecache(inode, start);
1943
1944         /* optimize grow case */
1945         if (grow) {
1946                 osd_execute_truncate(obj);
1947                 GOTO(out, rc);
1948         }
1949
1950         inode_lock(inode);
1951         /* add to orphan list to ensure truncate completion
1952          * if this transaction succeed. ldiskfs_truncate()
1953          * will take the inode out of the list */
1954         rc = ldiskfs_orphan_add(oh->ot_handle, inode);
1955         inode_unlock(inode);
1956         if (rc != 0)
1957                 GOTO(out, rc);
1958
1959         list_for_each_entry(al, &oh->ot_trunc_locks, tl_list) {
1960                 if (obj != al->tl_obj)
1961                         continue;
1962                 LASSERT(al->tl_shared == 0);
1963                 found = 1;
1964                 /* do actual truncate in osd_trans_stop() */
1965                 al->tl_truncate = 1;
1966                 break;
1967         }
1968         LASSERT(found);
1969
1970 out:
1971         RETURN(rc);
1972 }
1973
1974 static int fiemap_check_ranges(struct inode *inode,
1975                                u64 start, u64 len, u64 *new_len)
1976 {
1977         loff_t maxbytes;
1978
1979         *new_len = len;
1980
1981         if (len == 0)
1982                 return -EINVAL;
1983
1984         if (ldiskfs_test_inode_flag(inode, LDISKFS_INODE_EXTENTS))
1985                 maxbytes = inode->i_sb->s_maxbytes;
1986         else
1987                 maxbytes = LDISKFS_SB(inode->i_sb)->s_bitmap_maxbytes;
1988
1989         if (start > maxbytes)
1990                 return -EFBIG;
1991
1992         /*
1993          * Shrink request scope to what the fs can actually handle.
1994          */
1995         if (len > maxbytes || (maxbytes - len) < start)
1996                 *new_len = maxbytes - start;
1997
1998         return 0;
1999 }
2000
2001 /* So that the fiemap access checks can't overflow on 32 bit machines. */
2002 #define FIEMAP_MAX_EXTENTS     (UINT_MAX / sizeof(struct fiemap_extent))
2003
2004 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
2005                           struct fiemap *fm)
2006 {
2007         struct fiemap_extent_info fieinfo = {0, };
2008         struct inode *inode = osd_dt_obj(dt)->oo_inode;
2009         u64 len;
2010         int rc;
2011         mm_segment_t cur_fs;
2012
2013         LASSERT(inode);
2014         if (inode->i_op->fiemap == NULL)
2015                 return -EOPNOTSUPP;
2016
2017         if (fm->fm_extent_count > FIEMAP_MAX_EXTENTS)
2018                 return -EINVAL;
2019
2020         rc = fiemap_check_ranges(inode, fm->fm_start, fm->fm_length, &len);
2021         if (rc)
2022                 return rc;
2023
2024         fieinfo.fi_flags = fm->fm_flags;
2025         fieinfo.fi_extents_max = fm->fm_extent_count;
2026         fieinfo.fi_extents_start = fm->fm_extents;
2027
2028         if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
2029                 filemap_write_and_wait(inode->i_mapping);
2030
2031         /* Save previous value address limit */
2032         cur_fs = get_fs();
2033         /* Set the address limit of the kernel */
2034         set_fs(KERNEL_DS);
2035
2036         rc = inode->i_op->fiemap(inode, &fieinfo, fm->fm_start, len);
2037         fm->fm_flags = fieinfo.fi_flags;
2038         fm->fm_mapped_extents = fieinfo.fi_extents_mapped;
2039
2040         /* Restore the previous address limt */
2041         set_fs(cur_fs);
2042
2043         return rc;
2044 }
2045
2046 static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
2047                        __u64 start, __u64 end, enum lu_ladvise_type advice)
2048 {
2049         struct osd_object *obj = osd_dt_obj(dt);
2050         int rc = 0;
2051         ENTRY;
2052
2053         switch (advice) {
2054         case LU_LADVISE_DONTNEED:
2055                 if (end)
2056                         invalidate_mapping_pages(obj->oo_inode->i_mapping,
2057                                                  start >> PAGE_SHIFT,
2058                                                  (end - 1) >> PAGE_SHIFT);
2059                 break;
2060         default:
2061                 rc = -ENOTSUPP;
2062                 break;
2063         }
2064
2065         RETURN(rc);
2066 }
2067
2068 /*
2069  * in some cases we may need declare methods for objects being created
2070  * e.g., when we create symlink
2071  */
2072 const struct dt_body_operations osd_body_ops_new = {
2073         .dbo_declare_write = osd_declare_write,
2074 };
2075
2076 const struct dt_body_operations osd_body_ops = {
2077         .dbo_read                       = osd_read,
2078         .dbo_declare_write              = osd_declare_write,
2079         .dbo_write                      = osd_write,
2080         .dbo_bufs_get                   = osd_bufs_get,
2081         .dbo_bufs_put                   = osd_bufs_put,
2082         .dbo_write_prep                 = osd_write_prep,
2083         .dbo_declare_write_commit       = osd_declare_write_commit,
2084         .dbo_write_commit               = osd_write_commit,
2085         .dbo_read_prep                  = osd_read_prep,
2086         .dbo_declare_punch              = osd_declare_punch,
2087         .dbo_punch                      = osd_punch,
2088         .dbo_fiemap_get                 = osd_fiemap_get,
2089         .dbo_ladvise                    = osd_ladvise,
2090 };
2091
2092 /**
2093  * Get a truncate lock
2094  *
2095  * In order to take multi-transaction truncate out of main transaction we let
2096  * the caller grab a lock on the object passed. the lock can be shared (for
2097  * writes) and exclusive (for truncate). It's not allowed to mix truncate
2098  * and write in the same transaction handle (do not confuse with big ldiskfs
2099  * transaction containing lots of handles).
2100  * The lock must be taken at declaration.
2101  *
2102  * \param obj           object to lock
2103  * \oh                  transaction
2104  * \shared              shared or exclusive
2105  *
2106  * \retval 0            lock is granted
2107  * \retval -NOMEM       no memory to allocate lock
2108  */
2109 int osd_trunc_lock(struct osd_object *obj, struct osd_thandle *oh, bool shared)
2110 {
2111         struct osd_access_lock *al, *tmp;
2112
2113         LASSERT(obj);
2114         LASSERT(oh);
2115
2116         list_for_each_entry(tmp, &oh->ot_trunc_locks, tl_list) {
2117                 if (tmp->tl_obj != obj)
2118                         continue;
2119                 LASSERT(tmp->tl_shared == shared);
2120                 /* found same lock */
2121                 return 0;
2122         }
2123
2124         OBD_ALLOC_PTR(al);
2125         if (unlikely(al == NULL))
2126                 return -ENOMEM;
2127         al->tl_obj = obj;
2128         al->tl_truncate = false;
2129         if (shared)
2130                 down_read(&obj->oo_ext_idx_sem);
2131         else
2132                 down_write(&obj->oo_ext_idx_sem);
2133         al->tl_shared = shared;
2134
2135         list_add(&al->tl_list, &oh->ot_trunc_locks);
2136
2137         return 0;
2138 }
2139
2140 void osd_trunc_unlock_all(struct list_head *list)
2141 {
2142         struct osd_access_lock *al, *tmp;
2143         list_for_each_entry_safe(al, tmp, list, tl_list) {
2144                 if (al->tl_shared)
2145                         up_read(&al->tl_obj->oo_ext_idx_sem);
2146                 else
2147                         up_write(&al->tl_obj->oo_ext_idx_sem);
2148                 list_del(&al->tl_list);
2149                 OBD_FREE_PTR(al);
2150         }
2151 }
2152
2153 void osd_execute_truncate(struct osd_object *obj)
2154 {
2155         struct osd_device *d = osd_obj2dev(obj);
2156         struct inode *inode = obj->oo_inode;
2157         __u64 size;
2158
2159         /* simulate crash before (in the middle) of delayed truncate */
2160         if (OBD_FAIL_CHECK(OBD_FAIL_OSD_FAIL_AT_TRUNCATE)) {
2161                 struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
2162                 struct ldiskfs_sb_info *sbi = LDISKFS_SB(inode->i_sb);
2163
2164                 mutex_lock(&sbi->s_orphan_lock);
2165                 list_del_init(&ei->i_orphan);
2166                 mutex_unlock(&sbi->s_orphan_lock);
2167                 return;
2168         }
2169
2170         inode_lock(inode);
2171         ldiskfs_truncate(inode);
2172         inode_unlock(inode);
2173
2174         /*
2175          * For a partial-page truncate, flush the page to disk immediately to
2176          * avoid data corruption during direct disk write.  b=17397
2177          */
2178         size = i_size_read(inode);
2179         if ((size & ~PAGE_MASK) == 0)
2180                 return;
2181         if (osd_use_page_cache(d)) {
2182                 filemap_fdatawrite_range(inode->i_mapping, size, size + 1);
2183         } else {
2184                 /* Notice we use "wait" version to ensure I/O is complete */
2185                 filemap_write_and_wait_range(inode->i_mapping, size, size + 1);
2186                 invalidate_mapping_pages(inode->i_mapping, size >> PAGE_SHIFT,
2187                                          size >> PAGE_SHIFT);
2188         }
2189 }
2190
2191 void osd_process_truncates(struct list_head *list)
2192 {
2193         struct osd_access_lock *al;
2194
2195         LASSERT(journal_current_handle() == NULL);
2196
2197         list_for_each_entry(al, list, tl_list) {
2198                 if (al->tl_shared)
2199                         continue;
2200                 if (!al->tl_truncate)
2201                         continue;
2202                 osd_execute_truncate(al->tl_obj);
2203         }
2204 }