lustre/osd-ldiskfs/osd_io.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Whamcloud, Inc.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/osd/osd_io.c
  37  *
  38  * body operations
  39  *
  40  * Author: Nikita Danilov <nikita@clusterfs.com>
  41  * Author: Alex Zhuravlev <bzzz@whamcloud.com>
  42  *
  43  */
  44
  45 /* LUSTRE_VERSION_CODE */
  46 #include <lustre_ver.h>
  47 /* prerequisite for linux/xattr.h */
  48 #include <linux/types.h>
  49 /* prerequisite for linux/xattr.h */
  50 #include <linux/fs.h>
  51
  52 /* ext_depth() */
  53 #include <ldiskfs/ldiskfs.h>
  54 #include <ldiskfs/ldiskfs_jbd2.h>
  55 #include <ldiskfs/ldiskfs_extents.h>
  56
  57 /*
  58  * struct OBD_{ALLOC,FREE}*()
  59  * OBD_FAIL_CHECK
  60  */
  61 #include <obd_support.h>
  62
  63 #include "osd_internal.h"
  64
  65 #ifndef HAVE_PAGE_CONSTANT
  66 #define mapping_cap_page_constant_write(mapping) 0
  67 #define SetPageConstant(page) do {} while (0)
  68 #define ClearPageConstant(page) do {} while (0)
  69 #endif
  70
  71 #ifndef HAS_GENERIC_ERROR_REMOVE_PAGE
  72 int generic_error_remove_page(struct address_space *mapping, struct page *page)
  73 {
  74         if (mapping == NULL)
  75                 return -EINVAL;
  76
  77         if (mapping != page->mapping)
  78                 return -EIO;
  79         /*
  80          * Only punch for normal data pages for now.
  81          * Handling other types like directories would need more auditing.
  82          */
  83         if (!S_ISREG(mapping->host->i_mode))
  84                 return -EIO;
  85
  86         if (page_mapped(page)) {
  87                 unmap_mapping_range(mapping,
  88                                     (loff_t)page->index << PAGE_CACHE_SHIFT,
  89                                     PAGE_CACHE_SIZE, 0);
  90         }
  91         truncate_complete_page(mapping, page);
  92         return 0;
  93 }
  94 #endif
  95
  96 static void osd_init_iobuf(struct osd_device *d, struct osd_iobuf *iobuf,int rw)
  97 {
  98         cfs_waitq_init(&iobuf->dr_wait);
  99         cfs_atomic_set(&iobuf->dr_numreqs, 0);
 100         iobuf->dr_max_pages = PTLRPC_MAX_BRW_PAGES;
 101         iobuf->dr_npages = 0;
 102         iobuf->dr_error = 0;
 103         iobuf->dr_dev = d;
 104         iobuf->dr_frags = 0;
 105         iobuf->dr_elapsed = 0;
 106         /* must be counted before, so assert */
 107         LASSERT(iobuf->dr_elapsed_valid == 0);
 108         iobuf->dr_rw = rw;
 109 }
 110
 111 static void osd_iobuf_add_page(struct osd_iobuf *iobuf, struct page *page)
 112 {
 113         LASSERT(iobuf->dr_npages < iobuf->dr_max_pages);
 114         iobuf->dr_pages[iobuf->dr_npages++] = page;
 115 }
 116
 117 void osd_fini_iobuf(struct osd_device *d, struct osd_iobuf *iobuf)
 118 {
 119         int rw = iobuf->dr_rw;
 120
 121         if (iobuf->dr_elapsed_valid) {
 122                 iobuf->dr_elapsed_valid = 0;
 123                 LASSERT(iobuf->dr_dev == d);
 124                 LASSERT(iobuf->dr_frags > 0);
 125                 lprocfs_oh_tally(&d->od_brw_stats.
 126                                  hist[BRW_R_DIO_FRAGS+rw],
 127                                  iobuf->dr_frags);
 128                 lprocfs_oh_tally_log2(&d->od_brw_stats.hist[BRW_R_IO_TIME+rw],
 129                                       iobuf->dr_elapsed);
 130         }
 131 }
 132
 133 #ifdef HAVE_BIO_ENDIO_2ARG
 134 #define DIO_RETURN(a)
 135 static void dio_complete_routine(struct bio *bio, int error)
 136 #else
 137 #define DIO_RETURN(a)   return(a)
 138 static int dio_complete_routine(struct bio *bio, unsigned int done, int error)
 139 #endif
 140 {
 141         struct osd_iobuf *iobuf = bio->bi_private;
 142         struct bio_vec *bvl;
 143         int i;
 144
 145         /* CAVEAT EMPTOR: possibly in IRQ context
 146          * DO NOT record procfs stats here!!! */
 147
 148         if (unlikely(iobuf == NULL)) {
 149                 CERROR("***** bio->bi_private is NULL!  This should never "
 150                        "happen.  Normally, I would crash here, but instead I "
 151                        "will dump the bio contents to the console.  Please "
 152                        "report this to <http://jira.whamcloud.com/> , along "
 153                        "with any interesting messages leading up to this point "
 154                        "(like SCSI errors, perhaps).  Because bi_private is "
 155                        "NULL, I can't wake up the thread that initiated this "
 156                        "IO - you will probably have to reboot this node.\n");
 157                 CERROR("bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d, "
 158                        "bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, "
 159                        "bi_private: %p\n", bio->bi_next, bio->bi_flags,
 160                        bio->bi_rw, bio->bi_vcnt, bio->bi_idx, bio->bi_size,
 161                        bio->bi_end_io, cfs_atomic_read(&bio->bi_cnt),
 162                        bio->bi_private);
 163                 DIO_RETURN(0);
 164         }
 165
 166         /* the check is outside of the cycle for performance reason -bzzz */
 167         if (!cfs_test_bit(BIO_RW, &bio->bi_rw)) {
 168                 bio_for_each_segment(bvl, bio, i) {
 169                         if (likely(error == 0))
 170                                 SetPageUptodate(bvl->bv_page);
 171                         LASSERT(PageLocked(bvl->bv_page));
 172                         ClearPageConstant(bvl->bv_page);
 173                 }
 174                 cfs_atomic_dec(&iobuf->dr_dev->od_r_in_flight);
 175         } else {
 176                 struct page *p = iobuf->dr_pages[0];
 177                 if (p->mapping) {
 178                         if (mapping_cap_page_constant_write(p->mapping)) {
 179                                 bio_for_each_segment(bvl, bio, i) {
 180                                         ClearPageConstant(bvl->bv_page);
 181                                 }
 182                         }
 183                 }
 184                 cfs_atomic_dec(&iobuf->dr_dev->od_w_in_flight);
 185         }
 186
 187         /* any real error is good enough -bzzz */
 188         if (error != 0 && iobuf->dr_error == 0)
 189                 iobuf->dr_error = error;
 190
 191         if (cfs_atomic_dec_and_test(&iobuf->dr_numreqs)) {
 192                 iobuf->dr_elapsed = jiffies - iobuf->dr_start_time;
 193                 iobuf->dr_elapsed_valid = 1;
 194                 cfs_waitq_signal(&iobuf->dr_wait);
 195         }
 196
 197         /* Completed bios used to be chained off iobuf->dr_bios and freed in
 198          * filter_clear_dreq().  It was then possible to exhaust the biovec-256
 199          * mempool when serious on-disk fragmentation was encountered,
 200          * deadlocking the OST.  The bios are now released as soon as complete
 201          * so the pool cannot be exhausted while IOs are competing. bug 10076 */
 202         bio_put(bio);
 203         DIO_RETURN(0);
 204 }
 205
 206 static void record_start_io(struct osd_iobuf *iobuf, int size)
 207 {
 208         struct osd_device    *osd = iobuf->dr_dev;
 209         struct obd_histogram *h = osd->od_brw_stats.hist;
 210
 211         iobuf->dr_frags++;
 212         cfs_atomic_inc(&iobuf->dr_numreqs);
 213
 214         if (iobuf->dr_rw == 0) {
 215                 cfs_atomic_inc(&osd->od_r_in_flight);
 216                 lprocfs_oh_tally(&h[BRW_R_RPC_HIST],
 217                                  cfs_atomic_read(&osd->od_r_in_flight));
 218                 lprocfs_oh_tally_log2(&h[BRW_R_DISK_IOSIZE], size);
 219         } else if (iobuf->dr_rw == 1) {
 220                 cfs_atomic_inc(&osd->od_w_in_flight);
 221                 lprocfs_oh_tally(&h[BRW_W_RPC_HIST],
 222                                  cfs_atomic_read(&osd->od_w_in_flight));
 223                 lprocfs_oh_tally_log2(&h[BRW_W_DISK_IOSIZE], size);
 224         } else {
 225                 LBUG();
 226         }
 227 }
 228
 229 static void osd_submit_bio(int rw, struct bio *bio)
 230 {
 231         LASSERTF(rw == 0 || rw == 1, "%x\n", rw);
 232         if (rw == 0)
 233                 submit_bio(READ, bio);
 234         else
 235                 submit_bio(WRITE, bio);
 236 }
 237
 238 static int can_be_merged(struct bio *bio, sector_t sector)
 239 {
 240         unsigned int size;
 241
 242         if (!bio)
 243                 return 0;
 244
 245         size = bio->bi_size >> 9;
 246         return bio->bi_sector + size == sector ? 1 : 0;
 247 }
 248
 249 static int osd_do_bio(struct osd_device *osd, struct inode *inode,
 250                       struct osd_iobuf *iobuf)
 251 {
 252         int            blocks_per_page = CFS_PAGE_SIZE >> inode->i_blkbits;
 253         struct page  **pages = iobuf->dr_pages;
 254         int            npages = iobuf->dr_npages;
 255         unsigned long *blocks = iobuf->dr_blocks;
 256         int            total_blocks = npages * blocks_per_page;
 257         int            sector_bits = inode->i_sb->s_blocksize_bits - 9;
 258         unsigned int   blocksize = inode->i_sb->s_blocksize;
 259         struct bio    *bio = NULL;
 260         struct page   *page;
 261         unsigned int   page_offset;
 262         sector_t       sector;
 263         int            nblocks;
 264         int            block_idx;
 265         int            page_idx;
 266         int            i;
 267         int            rc = 0;
 268         ENTRY;
 269
 270         LASSERT(iobuf->dr_npages == npages);
 271
 272         osd_brw_stats_update(osd, iobuf);
 273         iobuf->dr_start_time = cfs_time_current();
 274
 275         for (page_idx = 0, block_idx = 0;
 276              page_idx < npages;
 277              page_idx++, block_idx += blocks_per_page) {
 278
 279                 page = pages[page_idx];
 280                 LASSERT(block_idx + blocks_per_page <= total_blocks);
 281
 282                 for (i = 0, page_offset = 0;
 283                      i < blocks_per_page;
 284                      i += nblocks, page_offset += blocksize * nblocks) {
 285
 286                         nblocks = 1;
 287
 288                         if (blocks[block_idx + i] == 0) {  /* hole */
 289                                 LASSERTF(iobuf->dr_rw == 0,
 290                                          "page_idx %u, block_idx %u, i %u\n",
 291                                          page_idx, block_idx, i);
 292                                 memset(kmap(page) + page_offset, 0, blocksize);
 293                                 kunmap(page);
 294                                 continue;
 295                         }
 296
 297                         sector = (sector_t)blocks[block_idx + i] << sector_bits;
 298
 299                         /* Additional contiguous file blocks? */
 300                         while (i + nblocks < blocks_per_page &&
 301                                (sector + (nblocks << sector_bits)) ==
 302                                ((sector_t)blocks[block_idx + i + nblocks] <<
 303                                 sector_bits))
 304                                 nblocks++;
 305
 306                         /* I only set the page to be constant only if it
 307                          * is mapped to a contiguous underlying disk block(s).
 308                          * It will then make sure the corresponding device
 309                          * cache of raid5 will be overwritten by this page.
 310                          * - jay */
 311                         if (iobuf->dr_rw && (nblocks == blocks_per_page) &&
 312                             mapping_cap_page_constant_write(inode->i_mapping))
 313                                 SetPageConstant(page);
 314
 315                         if (bio != NULL &&
 316                             can_be_merged(bio, sector) &&
 317                             bio_add_page(bio, page,
 318                                          blocksize * nblocks, page_offset) != 0)
 319                                 continue;       /* added this frag OK */
 320
 321                         if (bio != NULL) {
 322                                 struct request_queue *q =
 323                                         bdev_get_queue(bio->bi_bdev);
 324
 325                                 /* Dang! I have to fragment this I/O */
 326                                 CDEBUG(D_INODE, "bio++ sz %d vcnt %d(%d) "
 327                                        "sectors %d(%d) psg %d(%d) hsg %d(%d)\n",
 328                                        bio->bi_size,
 329                                        bio->bi_vcnt, bio->bi_max_vecs,
 330                                        bio->bi_size >> 9, queue_max_sectors(q),
 331                                        bio_phys_segments(q, bio),
 332                                        queue_max_phys_segments(q),
 333                                        bio_hw_segments(q, bio),
 334                                        queue_max_hw_segments(q));
 335
 336                                 record_start_io(iobuf, bio->bi_size);
 337                                 osd_submit_bio(iobuf->dr_rw, bio);
 338                         }
 339
 340                         /* allocate new bio, limited by max BIO size, b=9945 */
 341                         bio = bio_alloc(GFP_NOIO, max(BIO_MAX_PAGES,
 342                                                       (npages - page_idx) *
 343                                                       blocks_per_page));
 344                         if (bio == NULL) {
 345                                 CERROR("Can't allocate bio %u*%u = %u pages\n",
 346                                        (npages - page_idx), blocks_per_page,
 347                                        (npages - page_idx) * blocks_per_page);
 348                                 rc = -ENOMEM;
 349                                 goto out;
 350                         }
 351
 352                         bio->bi_bdev = inode->i_sb->s_bdev;
 353                         bio->bi_sector = sector;
 354                         bio->bi_end_io = dio_complete_routine;
 355                         bio->bi_private = iobuf;
 356
 357                         rc = bio_add_page(bio, page,
 358                                           blocksize * nblocks, page_offset);
 359                         LASSERT(rc != 0);
 360                 }
 361         }
 362
 363         if (bio != NULL) {
 364                 record_start_io(iobuf, bio->bi_size);
 365                 osd_submit_bio(iobuf->dr_rw, bio);
 366                 rc = 0;
 367         }
 368
 369  out:
 370         /* in order to achieve better IO throughput, we don't wait for writes
 371          * completion here. instead we proceed with transaction commit in
 372          * parallel and wait for IO completion once transaction is stopped
 373          * see osd_trans_stop() for more details -bzzz */
 374         if (iobuf->dr_rw == 0) {
 375                 cfs_wait_event(iobuf->dr_wait,
 376                                cfs_atomic_read(&iobuf->dr_numreqs) == 0);
 377         }
 378
 379         if (rc == 0)
 380                 rc = iobuf->dr_error;
 381         RETURN(rc);
 382 }
 383
 384 static int osd_map_remote_to_local(loff_t offset, ssize_t len, int *nrpages,
 385                                    struct niobuf_local *lnb)
 386 {
 387         ENTRY;
 388
 389         *nrpages = 0;
 390
 391         while (len > 0) {
 392                 int poff = offset & (CFS_PAGE_SIZE - 1);
 393                 int plen = CFS_PAGE_SIZE - poff;
 394
 395                 if (plen > len)
 396                         plen = len;
 397                 lnb->offset = offset;
 398                 /* lnb->lnb_page_offset = poff; */
 399                 lnb->len = plen;
 400                 /* lb->flags = rnb->flags; */
 401                 lnb->flags = 0;
 402                 lnb->page = NULL;
 403                 lnb->rc = 0;
 404
 405                 LASSERTF(plen <= len, "plen %u, len %lld\n", plen,
 406                          (long long) len);
 407                 offset += plen;
 408                 len -= plen;
 409                 lnb++;
 410                 (*nrpages)++;
 411         }
 412
 413         RETURN(0);
 414 }
 415
 416 struct page *osd_get_page(struct dt_object *dt, loff_t offset, int rw)
 417 {
 418         struct inode      *inode = osd_dt_obj(dt)->oo_inode;
 419         struct osd_device *d = osd_obj2dev(osd_dt_obj(dt));
 420         struct page       *page;
 421
 422         LASSERT(inode);
 423
 424         page = find_or_create_page(inode->i_mapping, offset >> CFS_PAGE_SHIFT,
 425                                    GFP_NOFS | __GFP_HIGHMEM);
 426         if (unlikely(page == NULL))
 427                 lprocfs_counter_add(d->od_stats, LPROC_OSD_NO_PAGE, 1);
 428
 429         return page;
 430 }
 431
 432 /*
 433  * there are following "locks":
 434  * journal_start
 435  * i_alloc_sem
 436  * i_mutex
 437  * page lock
 438
 439  * osd write path
 440     * lock page(s)
 441     * journal_start
 442     * truncate_sem
 443
 444  * ext4 vmtruncate:
 445     * lock pages, unlock
 446     * journal_start
 447     * lock partial page
 448     * i_data_sem
 449
 450 */
 451 int osd_bufs_get(const struct lu_env *env, struct dt_object *d, loff_t pos,
 452                  ssize_t len, struct niobuf_local *lnb, int rw,
 453                  struct lustre_capa *capa)
 454 {
 455         struct osd_object   *obj    = osd_dt_obj(d);
 456         int npages, i, rc = 0;
 457
 458         LASSERT(obj->oo_inode);
 459
 460         osd_map_remote_to_local(pos, len, &npages, lnb);
 461
 462         for (i = 0; i < npages; i++, lnb++) {
 463
 464                 /* We still set up for ungranted pages so that granted pages
 465                  * can be written to disk as they were promised, and portals
 466                  * needs to keep the pages all aligned properly. */
 467                 lnb->dentry = (void *) obj;
 468
 469                 lnb->page = osd_get_page(d, lnb->offset, rw);
 470                 if (lnb->page == NULL)
 471                         GOTO(cleanup, rc = -ENOMEM);
 472
 473                 /* DLM locking protects us from write and truncate competing
 474                  * for same region, but truncate can leave dirty page in the
 475                  * cache. it's possible the writeout on a such a page is in
 476                  * progress when we access it. it's also possible that during
 477                  * this writeout we put new (partial) data, but then won't
 478                  * be able to proceed in filter_commitrw_write(). thus let's
 479                  * just wait for writeout completion, should be rare enough.
 480                  * -bzzz */
 481                 wait_on_page_writeback(lnb->page);
 482                 BUG_ON(PageWriteback(lnb->page));
 483
 484                 lu_object_get(&d->do_lu);
 485         }
 486         rc = i;
 487
 488 cleanup:
 489         RETURN(rc);
 490 }
 491
 492 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 493                         struct niobuf_local *lnb, int npages)
 494 {
 495         struct osd_thread_info *oti = osd_oti_get(env);
 496         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 497         struct osd_device      *d = osd_obj2dev(osd_dt_obj(dt));
 498         int                     i;
 499
 500         /* to do IO stats, notice we do this here because
 501          * osd_do_bio() doesn't wait for write to complete */
 502         osd_fini_iobuf(d, iobuf);
 503
 504         for (i = 0; i < npages; i++) {
 505                 if (lnb[i].page == NULL)
 506                         continue;
 507                 LASSERT(PageLocked(lnb[i].page));
 508                 unlock_page(lnb[i].page);
 509                 page_cache_release(lnb[i].page);
 510                 lu_object_put(env, &dt->do_lu);
 511                 lnb[i].page = NULL;
 512         }
 513         RETURN(0);
 514 }
 515
 516 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 517                           struct niobuf_local *lnb, int npages)
 518 {
 519         struct osd_thread_info *oti   = osd_oti_get(env);
 520         struct osd_iobuf       *iobuf = &oti->oti_iobuf;
 521         struct inode           *inode = osd_dt_obj(dt)->oo_inode;
 522         struct osd_device      *osd   = osd_obj2dev(osd_dt_obj(dt));
 523         struct timeval          start;
 524         struct timeval          end;
 525         unsigned long           timediff;
 526         ssize_t                 isize;
 527         __s64                   maxidx;
 528         int                     rc = 0;
 529         int                     i;
 530         int                     cache = 0;
 531
 532         LASSERT(inode);
 533
 534         osd_init_iobuf(osd, iobuf, 0);
 535
 536         isize = i_size_read(inode);
 537         maxidx = ((isize + CFS_PAGE_SIZE - 1) >> CFS_PAGE_SHIFT) - 1;
 538
 539         if (osd->od_writethrough_cache)
 540                 cache = 1;
 541         if (isize > osd->od_readcache_max_filesize)
 542                 cache = 0;
 543
 544         cfs_gettimeofday(&start);
 545         for (i = 0; i < npages; i++) {
 546
 547                 if (cache == 0)
 548                         generic_error_remove_page(inode->i_mapping,
 549                                                   lnb[i].page);
 550
 551                 /*
 552                  * till commit the content of the page is undefined
 553                  * we'll set it uptodate once bulk is done. otherwise
 554                  * subsequent reads can access non-stable data
 555                  */
 556                 ClearPageUptodate(lnb[i].page);
 557
 558                 if (lnb[i].len == CFS_PAGE_SIZE)
 559                         continue;
 560
 561                 if (maxidx >= lnb[i].page->index) {
 562                         osd_iobuf_add_page(iobuf, lnb[i].page);
 563                 } else {
 564                         long off;
 565                         char *p = kmap(lnb[i].page);
 566
 567                         off = lnb[i].offset;
 568                         if (off)
 569                                 memset(p, 0, off);
 570                         off = lnb[i].offset + lnb[i].len;
 571                         off &= ~CFS_PAGE_MASK;
 572                         if (off)
 573                                 memset(p + off, 0, CFS_PAGE_SIZE - off);
 574                         kunmap(lnb[i].page);
 575                 }
 576         }
 577         cfs_gettimeofday(&end);
 578         timediff = cfs_timeval_sub(&end, &start, NULL);
 579         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 580
 581         if (iobuf->dr_npages) {
 582                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 583                                                        iobuf->dr_npages,
 584                                                        iobuf->dr_blocks,
 585                                                        oti->oti_created,
 586                                                        0, NULL);
 587                 if (likely(rc == 0)) {
 588                         rc = osd_do_bio(osd, inode, iobuf);
 589                         /* do IO stats for preparation reads */
 590                         osd_fini_iobuf(osd, iobuf);
 591                 }
 592         }
 593         RETURN(rc);
 594 }
 595
 596 static int osd_declare_write_commit(const struct lu_env *env,
 597                                     struct dt_object *dt,
 598                                     struct niobuf_local *lnb, int npages,
 599                                     struct thandle *handle)
 600 {
 601         const struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 602         struct inode            *inode = osd_dt_obj(dt)->oo_inode;
 603         struct osd_thandle      *oh;
 604         int                      extents = 1;
 605         int                      depth;
 606         int                      i;
 607         int                      newblocks;
 608         int                      old;
 609
 610         LASSERT(handle != NULL);
 611         oh = container_of0(handle, struct osd_thandle, ot_super);
 612         LASSERT(oh->ot_handle == NULL);
 613
 614         old = oh->ot_credits;
 615         newblocks = npages;
 616
 617         /* calculate number of extents (probably better to pass nb) */
 618         for (i = 1; i < npages; i++)
 619                 if (lnb[i].offset !=
 620                     lnb[i - 1].offset + lnb[i - 1].len)
 621                         extents++;
 622
 623         /*
 624          * each extent can go into new leaf causing a split
 625          * 5 is max tree depth: inode + 4 index blocks
 626          * with blockmaps, depth is 3 at most
 627          */
 628         if (LDISKFS_I(inode)->i_flags & LDISKFS_EXTENTS_FL) {
 629                 /*
 630                  * many concurrent threads may grow tree by the time
 631                  * our transaction starts. so, consider 2 is a min depth
 632                  */
 633                 depth = ext_depth(inode);
 634                 depth = max(depth, 1) + 1;
 635                 newblocks += depth;
 636                 oh->ot_credits++; /* inode */
 637                 oh->ot_credits += depth * 2 * extents;
 638         } else {
 639                 depth = 3;
 640                 newblocks += depth;
 641                 oh->ot_credits++; /* inode */
 642                 oh->ot_credits += depth * extents;
 643         }
 644
 645         /* each new block can go in different group (bitmap + gd) */
 646
 647         /* we can't dirty more bitmap blocks than exist */
 648         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_groups_count)
 649                 oh->ot_credits += LDISKFS_SB(osd_sb(osd))->s_groups_count;
 650         else
 651                 oh->ot_credits += newblocks;
 652
 653         /* we can't dirty more gd blocks than exist */
 654         if (newblocks > LDISKFS_SB(osd_sb(osd))->s_gdb_count)
 655                 oh->ot_credits += LDISKFS_SB(osd_sb(osd))->s_gdb_count;
 656         else
 657                 oh->ot_credits += newblocks;
 658
 659         RETURN(0);
 660 }
 661
 662 /* Check if a block is allocated or not */
 663 static int osd_is_mapped(struct inode *inode, obd_size offset)
 664 {
 665         sector_t (*fs_bmap)(struct address_space *, sector_t);
 666
 667         fs_bmap = inode->i_mapping->a_ops->bmap;
 668
 669         /* We can't know if we are overwriting or not */
 670         if (fs_bmap == NULL)
 671                 return 0;
 672
 673         if (fs_bmap(inode->i_mapping, offset >> inode->i_blkbits) == 0)
 674                 return 0;
 675
 676         return 1;
 677 }
 678
 679 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
 680                             struct niobuf_local *lnb, int npages,
 681                             struct thandle *thandle)
 682 {
 683         struct osd_thread_info *oti = osd_oti_get(env);
 684         struct osd_iobuf *iobuf = &oti->oti_iobuf;
 685         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 686         struct osd_device  *osd = osd_obj2dev(osd_dt_obj(dt));
 687         loff_t isize;
 688         int rc = 0, i;
 689
 690         LASSERT(inode);
 691
 692         osd_init_iobuf(osd, iobuf, 1);
 693         isize = i_size_read(inode);
 694
 695         for (i = 0; i < npages; i++) {
 696                 if (lnb[i].rc == -ENOSPC &&
 697                     osd_is_mapped(inode, lnb[i].offset)) {
 698                         /* Allow the write to proceed if overwriting an
 699                          * existing block */
 700                         lnb[i].rc = 0;
 701                 }
 702
 703                 if (lnb[i].rc) { /* ENOSPC, network RPC error, etc. */
 704                         CDEBUG(D_INODE, "Skipping [%d] == %d\n", i,
 705                                lnb[i].rc);
 706                         LASSERT(lnb[i].page);
 707                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 708                         continue;
 709                 }
 710
 711                 LASSERT(PageLocked(lnb[i].page));
 712                 LASSERT(!PageWriteback(lnb[i].page));
 713
 714                 if (lnb[i].offset + lnb[i].len > isize)
 715                         isize = lnb[i].offset + lnb[i].len;
 716
 717                 /*
 718                  * Since write and truncate are serialized by oo_sem, even
 719                  * partial-page truncate should not leave dirty pages in the
 720                  * page cache.
 721                  */
 722                 LASSERT(!PageDirty(lnb[i].page));
 723
 724                 SetPageUptodate(lnb[i].page);
 725
 726                 osd_iobuf_add_page(iobuf, lnb[i].page);
 727         }
 728
 729         if (OBD_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC)) {
 730                 rc = -ENOSPC;
 731         } else if (iobuf->dr_npages > 0) {
 732                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 733                                                        iobuf->dr_npages,
 734                                                        iobuf->dr_blocks,
 735                                                        oti->oti_created,
 736                                                        1, NULL);
 737         } else {
 738                 /* no pages to write, no transno is needed */
 739                 thandle->th_local = 1;
 740         }
 741
 742         if (likely(rc == 0)) {
 743                 if (isize > i_size_read(inode)) {
 744                         i_size_write(inode, isize);
 745                         LDISKFS_I(inode)->i_disksize = isize;
 746                         inode->i_sb->s_op->dirty_inode(inode);
 747                 }
 748
 749                 rc = osd_do_bio(osd, inode, iobuf);
 750                 /* we don't do stats here as in read path because
 751                  * write is async: we'll do this in osd_put_bufs() */
 752         }
 753
 754         if (unlikely(rc != 0)) {
 755                 /* if write fails, we should drop pages from the cache */
 756                 for (i = 0; i < npages; i++) {
 757                         if (lnb[i].page == NULL)
 758                                 continue;
 759                         LASSERT(PageLocked(lnb[i].page));
 760                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 761                 }
 762         }
 763
 764         RETURN(rc);
 765 }
 766
 767 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
 768                          struct niobuf_local *lnb, int npages)
 769 {
 770         struct osd_thread_info *oti = osd_oti_get(env);
 771         struct osd_iobuf *iobuf = &oti->oti_iobuf;
 772         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 773         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 774         struct timeval start, end;
 775         unsigned long timediff;
 776         int rc = 0, i, m = 0, cache = 0;
 777
 778         LASSERT(inode);
 779
 780         osd_init_iobuf(osd, iobuf, 0);
 781
 782         if (osd->od_read_cache)
 783                 cache = 1;
 784         if (i_size_read(inode) > osd->od_readcache_max_filesize)
 785                 cache = 0;
 786
 787         cfs_gettimeofday(&start);
 788         for (i = 0; i < npages; i++) {
 789
 790                 if (i_size_read(inode) <= lnb[i].offset)
 791                         /* If there's no more data, abort early.
 792                          * lnb->rc == 0, so it's easy to detect later. */
 793                         break;
 794
 795                 if (i_size_read(inode) <
 796                     lnb[i].offset + lnb[i].len - 1)
 797                         lnb[i].rc = i_size_read(inode) - lnb[i].offset;
 798                 else
 799                         lnb[i].rc = lnb[i].len;
 800                 m += lnb[i].len;
 801
 802                 lprocfs_counter_add(osd->od_stats, LPROC_OSD_CACHE_ACCESS, 1);
 803                 if (PageUptodate(lnb[i].page)) {
 804                         lprocfs_counter_add(osd->od_stats,
 805                                             LPROC_OSD_CACHE_HIT, 1);
 806                 } else {
 807                         lprocfs_counter_add(osd->od_stats,
 808                                             LPROC_OSD_CACHE_MISS, 1);
 809                         osd_iobuf_add_page(iobuf, lnb[i].page);
 810                 }
 811                 if (cache == 0)
 812                         generic_error_remove_page(inode->i_mapping,lnb[i].page);
 813         }
 814         cfs_gettimeofday(&end);
 815         timediff = cfs_timeval_sub(&end, &start, NULL);
 816         lprocfs_counter_add(osd->od_stats, LPROC_OSD_GET_PAGE, timediff);
 817
 818         if (iobuf->dr_npages) {
 819                 rc = osd->od_fsops->fs_map_inode_pages(inode, iobuf->dr_pages,
 820                                                        iobuf->dr_npages,
 821                                                        iobuf->dr_blocks,
 822                                                        oti->oti_created,
 823                                                        0, NULL);
 824                 rc = osd_do_bio(osd, inode, iobuf);
 825
 826                 /* IO stats will be done in osd_bufs_put() */
 827         }
 828
 829         RETURN(rc);
 830 }
 831
 832 /*
 833  * XXX: Another layering violation for now.
 834  *
 835  * We don't want to use ->f_op->read methods, because generic file write
 836  *
 837  *         - serializes on ->i_sem, and
 838  *
 839  *         - does a lot of extra work like balance_dirty_pages(),
 840  *
 841  * which doesn't work for globally shared files like /last_rcvd.
 842  */
 843 static int osd_ldiskfs_readlink(struct inode *inode, char *buffer, int buflen)
 844 {
 845         struct ldiskfs_inode_info *ei = LDISKFS_I(inode);
 846
 847         memcpy(buffer, (char *)ei->i_data, buflen);
 848
 849         return  buflen;
 850 }
 851
 852 int osd_ldiskfs_read(struct inode *inode, void *buf, int size, loff_t *offs)
 853 {
 854         struct buffer_head *bh;
 855         unsigned long block;
 856         int osize;
 857         int blocksize;
 858         int csize;
 859         int boffs;
 860         int err;
 861
 862         /* prevent reading after eof */
 863         cfs_spin_lock(&inode->i_lock);
 864         if (i_size_read(inode) < *offs + size) {
 865                 size = i_size_read(inode) - *offs;
 866                 cfs_spin_unlock(&inode->i_lock);
 867                 if (size < 0) {
 868                         CDEBUG(D_EXT2, "size %llu is too short to read @%llu\n",
 869                                i_size_read(inode), *offs);
 870                         return -EBADR;
 871                 } else if (size == 0) {
 872                         return 0;
 873                 }
 874         } else {
 875                 cfs_spin_unlock(&inode->i_lock);
 876         }
 877
 878         blocksize = 1 << inode->i_blkbits;
 879         osize = size;
 880         while (size > 0) {
 881                 block = *offs >> inode->i_blkbits;
 882                 boffs = *offs & (blocksize - 1);
 883                 csize = min(blocksize - boffs, size);
 884                 bh = ldiskfs_bread(NULL, inode, block, 0, &err);
 885                 if (!bh) {
 886                         CERROR("%s: can't read %u@%llu on ino %lu: rc = %d\n",
 887                                LDISKFS_SB(inode->i_sb)->s_es->s_volume_name,
 888                                csize, *offs, inode->i_ino, err);
 889                         return err;
 890                 }
 891
 892                 memcpy(buf, bh->b_data + boffs, csize);
 893                 brelse(bh);
 894
 895                 *offs += csize;
 896                 buf += csize;
 897                 size -= csize;
 898         }
 899         return osize;
 900 }
 901
 902 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
 903                         struct lu_buf *buf, loff_t *pos,
 904                         struct lustre_capa *capa)
 905 {
 906         struct inode *inode = osd_dt_obj(dt)->oo_inode;
 907         int           rc;
 908
 909         if (osd_object_auth(env, dt, capa, CAPA_OPC_BODY_READ))
 910                 RETURN(-EACCES);
 911
 912         /* Read small symlink from inode body as we need to maintain correct
 913          * on-disk symlinks for ldiskfs.
 914          */
 915         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
 916             (buf->lb_len <= sizeof(LDISKFS_I(inode)->i_data)))
 917                 rc = osd_ldiskfs_readlink(inode, buf->lb_buf, buf->lb_len);
 918         else
 919                 rc = osd_ldiskfs_read(inode, buf->lb_buf, buf->lb_len, pos);
 920
 921         return rc;
 922 }
 923
 924 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
 925                                  const loff_t size, loff_t pos,
 926                                  struct thandle *handle)
 927 {
 928         struct osd_thandle *oh;
 929         int                 credits;
 930
 931         LASSERT(handle != NULL);
 932
 933         oh = container_of0(handle, struct osd_thandle, ot_super);
 934         LASSERT(oh->ot_handle == NULL);
 935
 936         /* XXX: size == 0 or INT_MAX indicating a catalog header update or
 937          *      llog write, see comment in mdd_declare_llog_record().
 938          *
 939          *      This hack will be removed with llog over OSD landing
 940          */
 941         if (size == DECLARE_LLOG_REWRITE)
 942                 credits = 2;
 943         else if (size == DECLARE_LLOG_WRITE)
 944                 credits = 6;
 945         else
 946                 credits = osd_dto_credits_noquota[DTO_WRITE_BLOCK];
 947
 948         OSD_DECLARE_OP(oh, write);
 949         oh->ot_credits += credits;
 950
 951         if (osd_dt_obj(dt)->oo_inode == NULL)
 952                 return 0;
 953
 954         osd_declare_qid(dt, oh, USRQUOTA, osd_dt_obj(dt)->oo_inode->i_uid,
 955                         osd_dt_obj(dt)->oo_inode);
 956         osd_declare_qid(dt, oh, GRPQUOTA, osd_dt_obj(dt)->oo_inode->i_gid,
 957                         osd_dt_obj(dt)->oo_inode);
 958         return 0;
 959 }
 960
 961 static int osd_ldiskfs_writelink(struct inode *inode, char *buffer, int buflen)
 962 {
 963
 964         memcpy((char *)&LDISKFS_I(inode)->i_data, (char *)buffer, buflen);
 965         LDISKFS_I(inode)->i_disksize = buflen;
 966         i_size_write(inode, buflen);
 967         inode->i_sb->s_op->dirty_inode(inode);
 968
 969         return 0;
 970 }
 971
 972 int osd_ldiskfs_write_record(struct inode *inode, void *buf, int bufsize,
 973                              loff_t *offs, handle_t *handle)
 974 {
 975         struct buffer_head *bh        = NULL;
 976         loff_t              offset    = *offs;
 977         loff_t              new_size  = i_size_read(inode);
 978         unsigned long       block;
 979         int                 blocksize = 1 << inode->i_blkbits;
 980         int                 err = 0;
 981         int                 size;
 982         int                 boffs;
 983         int                 dirty_inode = 0;
 984
 985         while (bufsize > 0) {
 986                 if (bh != NULL)
 987                         brelse(bh);
 988
 989                 block = offset >> inode->i_blkbits;
 990                 boffs = offset & (blocksize - 1);
 991                 size = min(blocksize - boffs, bufsize);
 992                 bh = ldiskfs_bread(handle, inode, block, 1, &err);
 993                 if (!bh) {
 994                         CERROR("%s: error reading offset %llu (block %lu): "
 995                                "rc = %d\n",
 996                                inode->i_sb->s_id, offset, block, err);
 997                         break;
 998                 }
 999
1000                 err = ldiskfs_journal_get_write_access(handle, bh);
1001                 if (err) {
1002                         CERROR("journal_get_write_access() returned error %d\n",
1003                                err);
1004                         break;
1005                 }
1006                 LASSERTF(boffs + size <= bh->b_size,
1007                          "boffs %d size %d bh->b_size %lu",
1008                          boffs, size, (unsigned long)bh->b_size);
1009                 memcpy(bh->b_data + boffs, buf, size);
1010                 err = ldiskfs_journal_dirty_metadata(handle, bh);
1011                 if (err)
1012                         break;
1013
1014                 if (offset + size > new_size)
1015                         new_size = offset + size;
1016                 offset += size;
1017                 bufsize -= size;
1018                 buf += size;
1019         }
1020         if (bh)
1021                 brelse(bh);
1022
1023         /* correct in-core and on-disk sizes */
1024         if (new_size > i_size_read(inode)) {
1025                 cfs_spin_lock(&inode->i_lock);
1026                 if (new_size > i_size_read(inode))
1027                         i_size_write(inode, new_size);
1028                 if (i_size_read(inode) > LDISKFS_I(inode)->i_disksize) {
1029                         LDISKFS_I(inode)->i_disksize = i_size_read(inode);
1030                         dirty_inode = 1;
1031                 }
1032                 cfs_spin_unlock(&inode->i_lock);
1033                 if (dirty_inode)
1034                         inode->i_sb->s_op->dirty_inode(inode);
1035         }
1036
1037         if (err == 0)
1038                 *offs = offset;
1039         return err;
1040 }
1041
1042 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
1043                          const struct lu_buf *buf, loff_t *pos,
1044                          struct thandle *handle, struct lustre_capa *capa,
1045                          int ignore_quota)
1046 {
1047         struct inode       *inode = osd_dt_obj(dt)->oo_inode;
1048         struct osd_thandle *oh;
1049         ssize_t             result;
1050 #ifdef HAVE_QUOTA_SUPPORT
1051         cfs_cap_t           save = cfs_curproc_cap_pack();
1052 #endif
1053
1054         LASSERT(dt_object_exists(dt));
1055
1056         if (osd_object_auth(env, dt, capa, CAPA_OPC_BODY_WRITE))
1057                 return -EACCES;
1058
1059         LASSERT(handle != NULL);
1060
1061         /* XXX: don't check: one declared chunk can be used many times */
1062         /* OSD_EXEC_OP(handle, write); */
1063
1064         oh = container_of(handle, struct osd_thandle, ot_super);
1065         LASSERT(oh->ot_handle->h_transaction != NULL);
1066 #ifdef HAVE_QUOTA_SUPPORT
1067         if (ignore_quota)
1068                 cfs_cap_raise(CFS_CAP_SYS_RESOURCE);
1069         else
1070                 cfs_cap_lower(CFS_CAP_SYS_RESOURCE);
1071 #endif
1072         /* Write small symlink to inode body as we need to maintain correct
1073          * on-disk symlinks for ldiskfs.
1074          */
1075         if (S_ISLNK(dt->do_lu.lo_header->loh_attr) &&
1076             (buf->lb_len < sizeof(LDISKFS_I(inode)->i_data)))
1077                 result = osd_ldiskfs_writelink(inode, buf->lb_buf, buf->lb_len);
1078         else
1079                 result = osd_ldiskfs_write_record(inode, buf->lb_buf,
1080                                                   buf->lb_len, pos,
1081                                                   oh->ot_handle);
1082 #ifdef HAVE_QUOTA_SUPPORT
1083         cfs_curproc_cap_unpack(save);
1084 #endif
1085         if (result == 0)
1086                 result = buf->lb_len;
1087         return result;
1088 }
1089
1090 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1091                              __u64 start, __u64 end, struct thandle *th)
1092 {
1093         struct osd_thandle *oh;
1094         ENTRY;
1095
1096         LASSERT(th);
1097         oh = container_of(th, struct osd_thandle, ot_super);
1098
1099         OSD_DECLARE_OP(oh, punch);
1100
1101         /*
1102          * we don't need to reserve credits for whole truncate
1103          * it's not possible as truncate may need to free too many
1104          * blocks and that won't fit a single transaction. instead
1105          * we reserve credits to change i_size and put inode onto
1106          * orphan list. if needed truncate will extend or restart
1107          * transaction
1108          */
1109         oh->ot_credits += osd_dto_credits_noquota[DTO_ATTR_SET_BASE];
1110         oh->ot_credits += 3;
1111
1112         RETURN(0);
1113 }
1114
1115 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1116                      __u64 start, __u64 end, struct thandle *th,
1117                      struct lustre_capa *capa)
1118 {
1119         struct osd_thandle *oh;
1120         struct osd_object  *obj = osd_dt_obj(dt);
1121         struct inode       *inode = obj->oo_inode;
1122         handle_t           *h;
1123         tid_t               tid;
1124         int                 rc, rc2 = 0;
1125         ENTRY;
1126
1127         LASSERT(end == OBD_OBJECT_EOF);
1128         LASSERT(dt_object_exists(dt));
1129         LASSERT(osd_invariant(obj));
1130
1131         LASSERT(th);
1132         oh = container_of(th, struct osd_thandle, ot_super);
1133         LASSERT(oh->ot_handle->h_transaction != NULL);
1134
1135         OSD_EXEC_OP(th, punch);
1136
1137         tid = oh->ot_handle->h_transaction->t_tid;
1138
1139         rc = vmtruncate(inode, start);
1140
1141         /*
1142          * For a partial-page truncate, flush the page to disk immediately to
1143          * avoid data corruption during direct disk write.  b=17397
1144          */
1145         if (rc == 0 && (start & ~CFS_PAGE_MASK) != 0)
1146                 rc = filemap_fdatawrite_range(inode->i_mapping, start, start+1);
1147
1148         h = journal_current_handle();
1149         LASSERT(h != NULL);
1150         LASSERT(h == oh->ot_handle);
1151
1152         if (tid != h->h_transaction->t_tid) {
1153                 int credits = oh->ot_credits;
1154                 /*
1155                  * transaction has changed during truncate
1156                  * we need to restart the handle with our credits
1157                  */
1158                 if (h->h_buffer_credits < credits) {
1159                         if (ldiskfs_journal_extend(h, credits))
1160                                 rc2 = ldiskfs_journal_restart(h, credits);
1161                 }
1162         }
1163
1164         RETURN(rc == 0 ? rc2 : rc);
1165 }
1166
1167 static int osd_fiemap_get(const struct lu_env *env, struct dt_object *dt,
1168                           struct ll_user_fiemap *fm)
1169 {
1170         struct inode *inode = osd_dt_obj(dt)->oo_inode;
1171         struct osd_thread_info *info   = osd_oti_get(env);
1172         struct dentry          *dentry = &info->oti_obj_dentry;
1173         struct file            *file   = &info->oti_file;
1174         mm_segment_t            saved_fs;
1175         int rc;
1176
1177         LASSERT(inode);
1178         dentry->d_inode = inode;
1179         file->f_dentry = dentry;
1180         file->f_mapping = inode->i_mapping;
1181         file->f_op = inode->i_fop;
1182
1183         saved_fs = get_fs();
1184         set_fs(get_ds());
1185         /* ldiskfs_ioctl does not have a inode argument */
1186         if (inode->i_fop->unlocked_ioctl)
1187                 rc = inode->i_fop->unlocked_ioctl(file, FSFILT_IOC_FIEMAP,
1188                                                   (long)fm);
1189         else
1190                 rc = -ENOTTY;
1191         set_fs(saved_fs);
1192         return rc;
1193 }
1194
1195 /*
1196  * in some cases we may need declare methods for objects being created
1197  * e.g., when we create symlink
1198  */
1199 const struct dt_body_operations osd_body_ops_new = {
1200         .dbo_declare_write = osd_declare_write,
1201 };
1202
1203 const struct dt_body_operations osd_body_ops = {
1204         .dbo_read                 = osd_read,
1205         .dbo_declare_write        = osd_declare_write,
1206         .dbo_write                = osd_write,
1207         .dbo_bufs_get             = osd_bufs_get,
1208         .dbo_bufs_put             = osd_bufs_put,
1209         .dbo_write_prep           = osd_write_prep,
1210         .dbo_declare_write_commit = osd_declare_write_commit,
1211         .dbo_write_commit         = osd_write_commit,
1212         .dbo_read_prep            = osd_read_prep,
1213         .do_declare_punch         = osd_declare_punch,
1214         .do_punch                 = osd_punch,
1215         .dbo_fiemap_get           = osd_fiemap_get,
1216 };
1217