lustre/osd-zfs/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) 2009, 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  *
  31  * lustre/osd-zfs/osd_io.c
  32  *
  33  * Author: Alex Zhuravlev <bzzz@whamcloud.com>
  34  * Author: Mike Pershin <tappro@whamcloud.com>
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_OSD
  38
  39 #include <libcfs/libcfs.h>
  40 #include <obd_support.h>
  41 #include <lustre_net.h>
  42 #include <obd.h>
  43 #include <obd_class.h>
  44 #include <lustre_disk.h>
  45 #include <lustre_fid.h>
  46 #include <lustre_quota.h>
  47
  48 #include "osd_internal.h"
  49
  50 #include <sys/dnode.h>
  51 #include <sys/dbuf.h>
  52 #include <sys/spa.h>
  53 #include <sys/stat.h>
  54 #include <sys/zap.h>
  55 #include <sys/spa_impl.h>
  56 #include <sys/zfs_znode.h>
  57 #include <sys/dmu_tx.h>
  58 #include <sys/dmu_objset.h>
  59 #include <sys/dsl_prop.h>
  60 #include <sys/sa_impl.h>
  61 #include <sys/txg.h>
  62
  63 char osd_0copy_tag[] = "zerocopy";
  64
  65 static void dbuf_set_pending_evict(dmu_buf_t *db)
  66 {
  67         dmu_buf_impl_t *dbi = (dmu_buf_impl_t *)db;
  68         dbi->db_pending_evict = TRUE;
  69 }
  70
  71 static void record_start_io(struct osd_device *osd, int rw, int discont_pages)
  72 {
  73         struct brw_stats *h = &osd->od_brw_stats;
  74
  75         if (rw == READ) {
  76                 atomic_inc(&osd->od_r_in_flight);
  77                 lprocfs_oh_tally_pcpu(&h->bs_hist[BRW_R_RPC_HIST],
  78                                       atomic_read(&osd->od_r_in_flight));
  79                 lprocfs_oh_tally_pcpu(&h->bs_hist[BRW_R_DISCONT_PAGES],
  80                                       discont_pages);
  81         } else {
  82                 atomic_inc(&osd->od_w_in_flight);
  83                 lprocfs_oh_tally_pcpu(&h->bs_hist[BRW_W_RPC_HIST],
  84                                       atomic_read(&osd->od_w_in_flight));
  85                 lprocfs_oh_tally_pcpu(&h->bs_hist[BRW_W_DISCONT_PAGES],
  86                                       discont_pages);
  87         }
  88 }
  89
  90 static void record_end_io(struct osd_device *osd, int rw,
  91                           unsigned long elapsed, int disksize, int npages)
  92 {
  93         struct brw_stats *h = &osd->od_brw_stats;
  94
  95         if (rw == READ)
  96                 atomic_dec(&osd->od_r_in_flight);
  97         else
  98                 atomic_dec(&osd->od_w_in_flight);
  99
 100         lprocfs_oh_tally_log2_pcpu(&h->bs_hist[BRW_R_PAGES + rw], npages);
 101         if (disksize > 0)
 102                 lprocfs_oh_tally_log2_pcpu(&h->bs_hist[BRW_R_DISK_IOSIZE + rw],
 103                                            disksize);
 104         if (elapsed)
 105                 lprocfs_oh_tally_log2_pcpu(&h->bs_hist[BRW_R_IO_TIME + rw],
 106                                             elapsed);
 107 }
 108
 109 static ssize_t __osd_read(const struct lu_env *env, struct dt_object *dt,
 110                           struct lu_buf *buf, loff_t *pos, size_t *size)
 111 {
 112         struct osd_object *obj = osd_dt_obj(dt);
 113         uint64_t old_size;
 114         int rc;
 115
 116         LASSERT(dt_object_exists(dt));
 117         LASSERT(obj->oo_dn);
 118
 119         read_lock(&obj->oo_attr_lock);
 120         old_size = obj->oo_attr.la_size;
 121         read_unlock(&obj->oo_attr_lock);
 122
 123         if (*pos + *size > old_size) {
 124                 if (old_size < *pos)
 125                         return 0;
 126
 127                 *size = old_size - *pos;
 128         }
 129
 130         rc = osd_dmu_read(osd_obj2dev(obj), obj->oo_dn, *pos, *size,
 131                           buf->lb_buf, DMU_READ_PREFETCH);
 132         if (!rc) {
 133                 rc = *size;
 134                 *pos += *size;
 135         }
 136
 137         return rc;
 138 }
 139
 140 static ssize_t osd_read(const struct lu_env *env, struct dt_object *dt,
 141                         struct lu_buf *buf, loff_t *pos)
 142 {
 143         struct osd_device *osd = osd_obj2dev(osd_dt_obj(dt));
 144         size_t size = buf->lb_len;
 145         hrtime_t start = gethrtime();
 146         s64 delta_ms;
 147         int rc;
 148
 149         record_start_io(osd, READ, 0);
 150         rc = __osd_read(env, dt, buf, pos, &size);
 151         delta_ms = gethrtime() - start;
 152         do_div(delta_ms, NSEC_PER_MSEC);
 153         record_end_io(osd, READ, delta_ms, size, size >> PAGE_SHIFT);
 154
 155         return rc;
 156 }
 157
 158 static inline ssize_t osd_read_no_record(const struct lu_env *env,
 159                                          struct dt_object *dt,
 160                                          struct lu_buf *buf, loff_t *pos)
 161 {
 162         size_t size = buf->lb_len;
 163
 164         return __osd_read(env, dt, buf, pos, &size);
 165 }
 166
 167 static ssize_t osd_declare_write(const struct lu_env *env, struct dt_object *dt,
 168                                 const struct lu_buf *buf, loff_t pos,
 169                                 struct thandle *th)
 170 {
 171         struct osd_object  *obj  = osd_dt_obj(dt);
 172         struct osd_device  *osd = osd_obj2dev(obj);
 173         loff_t _pos = pos, max = 0;
 174         struct osd_thandle *oh;
 175         uint64_t            oid;
 176         ENTRY;
 177
 178         oh = container_of(th, struct osd_thandle, ot_super);
 179
 180         /* in some cases declare can race with creation (e.g. llog)
 181          * and we need to wait till object is initialized. notice
 182          * LOHA_EXISTs is supposed to be the last step in the
 183          * initialization */
 184
 185         /* size change (in dnode) will be declared by dmu_tx_hold_write() */
 186         if (dt_object_exists(dt))
 187                 oid = obj->oo_dn->dn_object;
 188         else
 189                 oid = DMU_NEW_OBJECT;
 190
 191         /* XXX: we still miss for append declaration support in ZFS
 192          *      -1 means append which is used by llog mostly, llog
 193          *      can grow upto LLOG_MIN_CHUNK_SIZE*8 records */
 194         max = max_t(loff_t, 256 * 8 * LLOG_MIN_CHUNK_SIZE,
 195                     obj->oo_attr.la_size + (2 << 20));
 196         if (pos == -1)
 197                 pos = max;
 198         if (obj->oo_dn) {
 199                 loff_t tstart, tend, end = pos + buf->lb_len;
 200                 dmu_tx_hold_t *txh;
 201
 202                 /* try to find a close declared window to fit/extend */
 203                 for (txh = list_head(&oh->ot_tx->tx_holds); txh != NULL;
 204                     txh = list_next(&oh->ot_tx->tx_holds, txh)) {
 205                         if (obj->oo_dn != txh->txh_dnode)
 206                                 continue;
 207                         if (txh->txh_type != THT_WRITE)
 208                                 continue;
 209
 210                         /* bytes already declared in this handle */
 211                         tstart = txh->txh_arg1;
 212                         tend = txh->txh_arg1 + txh->txh_arg2;
 213
 214                         if (pos < tstart)
 215                                 tstart = pos;
 216                         if (tend < end)
 217                                 tend = end;
 218                         /* if this is an append, then extend it */
 219                         if (_pos == -1 && txh->txh_arg1 == max)
 220                                 tend += buf->lb_len;
 221                         /* don't let too big appends */
 222                         if (tend - tstart > 4*1024*1024)
 223                                 continue;
 224                         if (pos >= tend || end <= tstart)
 225                                 continue;
 226
 227                         txh->txh_arg1 = tstart;
 228                         txh->txh_arg2 = tend - tstart;
 229                         return 0;
 230                 }
 231         }
 232         osd_tx_hold_write(oh->ot_tx, oid, obj->oo_dn, pos, buf->lb_len);
 233
 234         /* dt_declare_write() is usually called for system objects, such
 235          * as llog or last_rcvd files. We needn't enforce quota on those
 236          * objects, so always set the lqi_space as 0. */
 237         RETURN(osd_declare_quota(env, osd, obj->oo_attr.la_uid,
 238                                  obj->oo_attr.la_gid, obj->oo_attr.la_projid,
 239                                  0, oh, NULL, OSD_QID_BLK));
 240 }
 241
 242 static dmu_buf_t *osd_get_dbuf(struct osd_object *obj, uint64_t offset)
 243 {
 244         dmu_buf_t **dbs = obj->oo_dbs;
 245         uint64_t blkid;
 246         int i;
 247
 248         blkid = dbuf_whichblock(obj->oo_dn, 0, offset);
 249         for (i = 0; i < OSD_MAX_DBUFS; i++) {
 250                 dmu_buf_impl_t *dbi = (void *)dbs[i];
 251                 if (!dbs[i])
 252                         continue;
 253                 if (dbi->db_blkid == blkid)
 254                         return dbs[i];
 255         }
 256         return (dmu_buf_t *)dbuf_hold(obj->oo_dn, blkid, osd_0copy_tag);
 257 }
 258
 259 static void osd_put_dbuf(struct osd_object *obj, dmu_buf_t *db)
 260 {
 261         dmu_buf_t **dbs = obj->oo_dbs;
 262         int i;
 263
 264         for (i = 0; i < OSD_MAX_DBUFS; i++) {
 265                 if (dbs[i] == db)
 266                         return;
 267         }
 268         /* get rid of dbuf with blkd > 0 */
 269         for (i = 0; i < OSD_MAX_DBUFS; i++) {
 270                 if (dbs[i] == NULL) {
 271                         dbs[i] = db;
 272                         return;
 273                 }
 274                 if (dbs[i]->db_offset > 0) {
 275                         /* replace this one */
 276                         dbuf_rele((dmu_buf_impl_t *)dbs[i], osd_0copy_tag);
 277                         dbs[i] = db;
 278                         return;
 279                 }
 280         }
 281         LBUG();
 282 }
 283
 284 static ssize_t osd_write_llog_header(struct osd_object *obj,
 285                                      const struct lu_buf *buf, loff_t *pos,
 286                                      struct osd_thandle *oh)
 287 {
 288         int bufoff, tocpy;
 289         int len = buf->lb_len;
 290         loff_t offset = *pos;
 291         char *data = buf->lb_buf;
 292
 293         while (len > 0) {
 294                 dmu_buf_t *db = osd_get_dbuf(obj, offset);
 295
 296                 bufoff = offset - db->db_offset;
 297                 tocpy = MIN(db->db_size - bufoff, len);
 298                 if (tocpy == db->db_size)
 299                         dmu_buf_will_fill(db, oh->ot_tx);
 300                 else
 301                         dmu_buf_will_dirty(db, oh->ot_tx);
 302                 LASSERT(offset >= db->db_offset);
 303                 LASSERT(offset + tocpy <= db->db_offset + db->db_size);
 304                 (void) memcpy((char *)db->db_data + bufoff, data, tocpy);
 305
 306                 if (tocpy == db->db_size)
 307                         dmu_buf_fill_done(db, oh->ot_tx);
 308
 309                 offset += tocpy;
 310                 data += tocpy;
 311                 len -= tocpy;
 312
 313                 osd_put_dbuf(obj, db);
 314         }
 315
 316         return 0;
 317 }
 318
 319 static ssize_t osd_write(const struct lu_env *env, struct dt_object *dt,
 320                         const struct lu_buf *buf, loff_t *pos,
 321                         struct thandle *th)
 322 {
 323         struct osd_object  *obj  = osd_dt_obj(dt);
 324         struct osd_device  *osd = osd_obj2dev(obj);
 325         struct osd_thandle *oh;
 326         uint64_t            offset = *pos;
 327         int                 rc;
 328
 329         ENTRY;
 330
 331         LASSERT(dt_object_exists(dt));
 332         LASSERT(obj->oo_dn);
 333
 334         LASSERT(th != NULL);
 335         oh = container_of(th, struct osd_thandle, ot_super);
 336
 337         down_read(&obj->oo_guard);
 338         if (obj->oo_destroyed)
 339                 GOTO(out, rc = -ENOENT);
 340
 341         if (fid_is_llog(lu_object_fid(&dt->do_lu))) {
 342                 osd_write_llog_header(obj, buf, pos, oh);
 343         } else {
 344                 osd_dmu_write(osd, obj->oo_dn, offset, (uint64_t)buf->lb_len,
 345                               buf->lb_buf, oh->ot_tx);
 346         }
 347         write_lock(&obj->oo_attr_lock);
 348         if (obj->oo_attr.la_size < offset + buf->lb_len) {
 349                 obj->oo_attr.la_size = offset + buf->lb_len;
 350                 write_unlock(&obj->oo_attr_lock);
 351                 /* osd_object_sa_update() will be copying directly from oo_attr
 352                  * into dbuf.  any update within a single txg will copy the
 353                  * most actual */
 354                 rc = osd_object_sa_update(obj, SA_ZPL_SIZE(osd),
 355                                         &obj->oo_attr.la_size, 8, oh);
 356                 if (unlikely(rc))
 357                         GOTO(out, rc);
 358         } else {
 359                 write_unlock(&obj->oo_attr_lock);
 360         }
 361
 362         *pos += buf->lb_len;
 363         rc = buf->lb_len;
 364
 365 out:
 366         up_read(&obj->oo_guard);
 367         RETURN(rc);
 368 }
 369
 370 /*
 371  * XXX: for the moment I don't want to use lnb_flags for osd-internal
 372  *      purposes as it's not very well defined ...
 373  *      instead I use the lowest bit of the address so that:
 374  *        arc buffer:  .lnb_data = abuf          (arc we loan for write)
 375  *        dbuf buffer: .lnb_data = dbuf | 1      (dbuf we get for read)
 376  *        copy buffer: .lnb_page->mapping = obj (page we allocate for write)
 377  *
 378  *      bzzz, to blame
 379  */
 380 static int osd_bufs_put(const struct lu_env *env, struct dt_object *dt,
 381                         struct niobuf_local *lnb, int npages)
 382 {
 383         struct osd_object *obj  = osd_dt_obj(dt);
 384         struct osd_device *osd = osd_obj2dev(obj);
 385         unsigned long      ptr;
 386         int                i;
 387
 388         LASSERT(dt_object_exists(dt));
 389         LASSERT(obj->oo_dn);
 390
 391         for (i = 0; i < npages; i++) {
 392                 if (lnb[i].lnb_page == NULL)
 393                         continue;
 394                 if (lnb[i].lnb_page->mapping == (void *)obj) {
 395                         /* this is anonymous page allocated for copy-write */
 396                         lnb[i].lnb_page->mapping = NULL;
 397                         __free_page(lnb[i].lnb_page);
 398                         atomic_dec(&osd->od_zerocopy_alloc);
 399                 } else {
 400                         /* see comment in osd_bufs_get_read() */
 401                         ptr = (unsigned long)lnb[i].lnb_data;
 402                         if (ptr & 1UL) {
 403                                 ptr &= ~1UL;
 404                                 dmu_buf_rele((void *)ptr, osd_0copy_tag);
 405                                 atomic_dec(&osd->od_zerocopy_pin);
 406                         } else if (lnb[i].lnb_data != NULL) {
 407                                 int j, apages, abufsz;
 408                                 abufsz = arc_buf_size(lnb[i].lnb_data);
 409                                 apages = abufsz >> PAGE_SHIFT;
 410                                 /* these references to pages must be invalidated
 411                                  * to prevent access in osd_bufs_put() */
 412                                 for (j = 0; j < apages; j++)
 413                                         lnb[i + j].lnb_page = NULL;
 414                                 dmu_return_arcbuf(lnb[i].lnb_data);
 415                                 atomic_dec(&osd->od_zerocopy_loan);
 416                         }
 417                 }
 418                 lnb[i].lnb_page = NULL;
 419                 lnb[i].lnb_data = NULL;
 420         }
 421
 422         return 0;
 423 }
 424
 425 static inline struct page *kmem_to_page(void *addr)
 426 {
 427         if (is_vmalloc_addr(addr))
 428                 return vmalloc_to_page(addr);
 429         else
 430                 return virt_to_page(addr);
 431 }
 432
 433 /**
 434  * Prepare buffers for read.
 435  *
 436  * The function maps the range described by \a off and \a len to \a lnb array.
 437  * dmu_buf_hold_array_by_bonus() finds/creates appropriate ARC buffers, then
 438  * we fill \a lnb array with the pages storing ARC buffers. Notice the current
 439  * implementationt passes TRUE to dmu_buf_hold_array_by_bonus() to fill ARC
 440  * buffers with actual data, I/O is done in the conext of osd_bufs_get_read().
 441  * A better implementation would just return the buffers (potentially unfilled)
 442  * and subsequent osd_read_prep() would do I/O for many ranges concurrently.
 443  *
 444  * \param[in] env       environment
 445  * \param[in] obj       object
 446  * \param[in] off       offset in bytes
 447  * \param[in] len       the number of bytes to access
 448  * \param[out] lnb      array of local niobufs pointing to the buffers with data
 449  *
 450  * \retval              0 for success
 451  * \retval              negative error number of failure
 452  */
 453 static int osd_bufs_get_read(const struct lu_env *env, struct osd_object *obj,
 454                              loff_t off, ssize_t len, struct niobuf_local *lnb,
 455                              int maxlnb)
 456 {
 457         struct osd_device *osd = osd_obj2dev(obj);
 458         int rc, i, numbufs, npages = 0, drop_cache = 0;
 459         hrtime_t start = gethrtime();
 460         dmu_buf_t **dbp;
 461         s64 delta_ms;
 462
 463         ENTRY;
 464         record_start_io(osd, READ, 0);
 465
 466         if (obj->oo_attr.la_size >= osd->od_readcache_max_filesize)
 467                 drop_cache = 1;
 468
 469         /* grab buffers for read:
 470          * OSD API let us to grab buffers first, then initiate IO(s)
 471          * so that all required IOs will be done in parallel, but at the
 472          * moment DMU doesn't provide us with a method to grab buffers.
 473          * If we discover this is a vital for good performance we
 474          * can get own replacement for dmu_buf_hold_array_by_bonus().
 475          */
 476         while (len > 0 &&
 477                (obj->oo_dn->dn_datablkshift != 0 ||
 478                 off < obj->oo_dn->dn_datablksz)) {
 479                 if (obj->oo_dn->dn_datablkshift == 0 &&
 480                     off + len > obj->oo_dn->dn_datablksz)
 481                         len = obj->oo_dn->dn_datablksz - off;
 482
 483                 dbp = NULL;
 484                 if (unlikely(npages >= maxlnb))
 485                         GOTO(err, rc = -EOVERFLOW);
 486
 487                 rc = -dmu_buf_hold_array_by_bonus(&obj->oo_dn->dn_bonus->db,
 488                                                   off, len, TRUE, osd_0copy_tag,
 489                                                   &numbufs, &dbp);
 490                 if (unlikely(rc))
 491                         GOTO(err, rc);
 492
 493                 for (i = 0; i < numbufs; i++) {
 494                         int bufoff, tocpy, thispage;
 495                         void *dbf = dbp[i];
 496
 497                         LASSERT(len > 0);
 498
 499                         atomic_inc(&osd->od_zerocopy_pin);
 500
 501                         bufoff = off - dbp[i]->db_offset;
 502                         tocpy = min_t(int, dbp[i]->db_size - bufoff, len);
 503
 504                         /* kind of trick to differentiate dbuf vs. arcbuf */
 505                         LASSERT(((unsigned long)dbp[i] & 1) == 0);
 506                         dbf = (void *) ((unsigned long)dbp[i] | 1);
 507
 508                         while (tocpy > 0) {
 509                                 if (unlikely(npages >= maxlnb))
 510                                         GOTO(err, rc = -EOVERFLOW);
 511
 512                                 thispage = PAGE_SIZE;
 513                                 thispage -= bufoff & (PAGE_SIZE - 1);
 514                                 thispage = min(tocpy, thispage);
 515
 516                                 lnb->lnb_rc = 0;
 517                                 lnb->lnb_file_offset = off;
 518                                 lnb->lnb_page_offset = bufoff & ~PAGE_MASK;
 519                                 lnb->lnb_len = thispage;
 520                                 lnb->lnb_page = kmem_to_page(dbp[i]->db_data +
 521                                                              bufoff);
 522                                 /* mark just a single slot: we need this
 523                                  * reference to dbuf to be released once */
 524                                 lnb->lnb_data = dbf;
 525                                 dbf = NULL;
 526
 527                                 tocpy -= thispage;
 528                                 len -= thispage;
 529                                 bufoff += thispage;
 530                                 off += thispage;
 531
 532                                 npages++;
 533                                 lnb++;
 534                         }
 535
 536                         if (drop_cache)
 537                                 dbuf_set_pending_evict(dbp[i]);
 538
 539                         /* steal dbuf so dmu_buf_rele_array() can't release
 540                          * it */
 541                         dbp[i] = NULL;
 542                 }
 543
 544                 dmu_buf_rele_array(dbp, numbufs, osd_0copy_tag);
 545         }
 546
 547         delta_ms = gethrtime() - start;
 548         do_div(delta_ms, NSEC_PER_MSEC);
 549         record_end_io(osd, READ, delta_ms, npages * PAGE_SIZE, npages);
 550
 551         RETURN(npages);
 552
 553 err:
 554         LASSERT(rc < 0);
 555         if (dbp)
 556                 dmu_buf_rele_array(dbp, numbufs, osd_0copy_tag);
 557         osd_bufs_put(env, &obj->oo_dt, lnb - npages, npages);
 558         RETURN(rc);
 559 }
 560
 561 static inline arc_buf_t *osd_request_arcbuf(dnode_t *dn, size_t bs)
 562 {
 563         arc_buf_t *abuf;
 564
 565         abuf = dmu_request_arcbuf(&dn->dn_bonus->db, bs);
 566         if (unlikely(!abuf))
 567                 return ERR_PTR(-ENOMEM);
 568
 569 #if ZFS_VERSION_CODE < OBD_OCD_VERSION(0, 7, 0, 0)
 570         /**
 571          * ZFS prior to 0.7.0 doesn't guarantee PAGE_SIZE alignment for zio
 572          * blocks smaller than (PAGE_SIZE << 2). This poses a problem of
 573          * setting up page array for RDMA transfer. See LU-9305.
 574          */
 575         if ((unsigned long)abuf->b_data & ~PAGE_MASK) {
 576                 dmu_return_arcbuf(abuf);
 577                 return NULL;
 578         }
 579 #endif
 580
 581         return abuf;
 582 }
 583
 584 static int osd_bufs_get_write(const struct lu_env *env, struct osd_object *obj,
 585                               loff_t off, ssize_t len, struct niobuf_local *lnb,
 586                               int maxlnb)
 587 {
 588         struct osd_device *osd = osd_obj2dev(obj);
 589         int                poff, plen, off_in_block, sz_in_block;
 590         int                rc, i = 0, npages = 0;
 591         dnode_t *dn = obj->oo_dn;
 592         arc_buf_t *abuf;
 593         uint32_t bs = dn->dn_datablksz;
 594         ENTRY;
 595
 596         /*
 597          * currently only full blocks are subject to zerocopy approach:
 598          * so that we're sure nobody is trying to update the same block
 599          */
 600         while (len > 0) {
 601                 if (unlikely(npages >= maxlnb))
 602                         GOTO(out_err, rc = -EOVERFLOW);
 603
 604                 off_in_block = off & (bs - 1);
 605                 sz_in_block = min_t(int, bs - off_in_block, len);
 606
 607                 abuf = NULL;
 608                 if (sz_in_block == bs) {
 609                         /* full block, try to use zerocopy */
 610                         abuf = osd_request_arcbuf(dn, bs);
 611                         if (unlikely(IS_ERR(abuf)))
 612                                 GOTO(out_err, rc = PTR_ERR(abuf));
 613                 }
 614
 615                 if (abuf != NULL) {
 616                         atomic_inc(&osd->od_zerocopy_loan);
 617
 618                         /* go over pages arcbuf contains, put them as
 619                          * local niobufs for ptlrpc's bulks */
 620                         while (sz_in_block > 0) {
 621                                 plen = min_t(int, sz_in_block, PAGE_SIZE);
 622
 623                                 if (unlikely(npages >= maxlnb))
 624                                         GOTO(out_err, rc = -EOVERFLOW);
 625
 626                                 lnb[i].lnb_file_offset = off;
 627                                 lnb[i].lnb_page_offset = 0;
 628                                 lnb[i].lnb_len = plen;
 629                                 lnb[i].lnb_rc = 0;
 630                                 if (sz_in_block == bs)
 631                                         lnb[i].lnb_data = abuf;
 632                                 else
 633                                         lnb[i].lnb_data = NULL;
 634
 635                                 /* this one is not supposed to fail */
 636                                 lnb[i].lnb_page = kmem_to_page(abuf->b_data +
 637                                                         off_in_block);
 638                                 LASSERT(lnb[i].lnb_page);
 639
 640                                 lprocfs_counter_add(osd->od_stats,
 641                                                 LPROC_OSD_ZEROCOPY_IO, 1);
 642
 643                                 sz_in_block -= plen;
 644                                 len -= plen;
 645                                 off += plen;
 646                                 off_in_block += plen;
 647                                 i++;
 648                                 npages++;
 649                         }
 650                 } else {
 651                         if (off_in_block == 0 && len < bs &&
 652                                         off + len >= obj->oo_attr.la_size)
 653                                 lprocfs_counter_add(osd->od_stats,
 654                                                 LPROC_OSD_TAIL_IO, 1);
 655
 656                         /* can't use zerocopy, allocate temp. buffers */
 657                         poff = off & (PAGE_SIZE - 1);
 658                         while (sz_in_block > 0) {
 659                                 plen = min_t(int, poff + sz_in_block,
 660                                              PAGE_SIZE);
 661                                 plen -= poff;
 662
 663                                 if (unlikely(npages >= maxlnb))
 664                                         GOTO(out_err, rc = -EOVERFLOW);
 665
 666                                 lnb[i].lnb_file_offset = off;
 667                                 lnb[i].lnb_page_offset = poff;
 668                                 poff = 0;
 669
 670                                 lnb[i].lnb_len = plen;
 671                                 lnb[i].lnb_rc = 0;
 672                                 lnb[i].lnb_data = NULL;
 673
 674                                 lnb[i].lnb_page = alloc_page(OSD_GFP_IO);
 675                                 if (unlikely(lnb[i].lnb_page == NULL))
 676                                         GOTO(out_err, rc = -ENOMEM);
 677
 678                                 LASSERT(lnb[i].lnb_page->mapping == NULL);
 679                                 lnb[i].lnb_page->mapping = (void *)obj;
 680
 681                                 atomic_inc(&osd->od_zerocopy_alloc);
 682                                 lprocfs_counter_add(osd->od_stats,
 683                                                 LPROC_OSD_COPY_IO, 1);
 684
 685                                 sz_in_block -= plen;
 686                                 len -= plen;
 687                                 off += plen;
 688                                 i++;
 689                                 npages++;
 690                         }
 691                 }
 692         }
 693
 694         RETURN(npages);
 695
 696 out_err:
 697         osd_bufs_put(env, &obj->oo_dt, lnb, npages);
 698         RETURN(rc);
 699 }
 700
 701 static int osd_bufs_get(const struct lu_env *env, struct dt_object *dt,
 702                         loff_t offset, ssize_t len, struct niobuf_local *lnb,
 703                         int maxlnb, enum dt_bufs_type rw)
 704 {
 705         struct osd_object *obj  = osd_dt_obj(dt);
 706         int                rc;
 707
 708         down_read(&obj->oo_guard);
 709
 710         if (unlikely(!dt_object_exists(dt) || obj->oo_destroyed))
 711                 GOTO(out, rc = -ENOENT);
 712
 713         if (rw & DT_BUFS_TYPE_WRITE)
 714                 rc = osd_bufs_get_write(env, obj, offset, len, lnb, maxlnb);
 715         else
 716                 rc = osd_bufs_get_read(env, obj, offset, len, lnb, maxlnb);
 717
 718 out:
 719         up_read(&obj->oo_guard);
 720         return rc;
 721 }
 722
 723 static int osd_write_prep(const struct lu_env *env, struct dt_object *dt,
 724                         struct niobuf_local *lnb, int npages)
 725 {
 726         struct osd_object *obj = osd_dt_obj(dt);
 727
 728         LASSERT(dt_object_exists(dt));
 729         LASSERT(obj->oo_dn);
 730
 731         return 0;
 732 }
 733
 734 static inline uint64_t osd_roundup2blocksz(uint64_t size,
 735                                            uint64_t offset,
 736                                            uint32_t blksz)
 737 {
 738         LASSERT(blksz > 0);
 739
 740         size += offset % blksz;
 741
 742         if (likely(is_power_of_2(blksz)))
 743                 return round_up(size, blksz);
 744         else
 745                 return DIV_ROUND_UP_ULL(size, blksz) * blksz;
 746 }
 747
 748 static int osd_declare_write_commit(const struct lu_env *env,
 749                                     struct dt_object *dt,
 750                                     struct niobuf_local *lnb, int npages,
 751                                     struct thandle *th)
 752 {
 753         struct osd_object  *obj = osd_dt_obj(dt);
 754         struct osd_device  *osd = osd_obj2dev(obj);
 755         struct osd_thandle *oh;
 756         uint64_t            offset = 0;
 757         uint32_t            size = 0;
 758         uint32_t blksz = obj->oo_dn->dn_datablksz;
 759         int                 i, rc;
 760         bool synced = false;
 761         long long           space = 0;
 762         struct page        *last_page = NULL;
 763         unsigned long       discont_pages = 0;
 764         enum osd_quota_local_flags local_flags = 0;
 765         enum osd_qid_declare_flags declare_flags = OSD_QID_BLK;
 766         ENTRY;
 767
 768         LASSERT(dt_object_exists(dt));
 769         LASSERT(obj->oo_dn);
 770
 771         LASSERT(lnb);
 772         LASSERT(npages > 0);
 773
 774         oh = container_of(th, struct osd_thandle, ot_super);
 775
 776         for (i = 0; i < npages; i++) {
 777                 if (last_page && lnb[i].lnb_page->index != (last_page->index + 1))
 778                         ++discont_pages;
 779                 last_page = lnb[i].lnb_page;
 780                 if (lnb[i].lnb_rc)
 781                         /* ENOSPC, network RPC error, etc.
 782                          * We don't want to book space for pages which will be
 783                          * skipped in osd_write_commit(). Hence we skip pages
 784                          * with lnb_rc != 0 here too */
 785                         continue;
 786                 /* ignore quota for the whole request if any page is from
 787                  * client cache or written by root.
 788                  *
 789                  * XXX we could handle this on per-lnb basis as done by
 790                  * grant. */
 791                 if ((lnb[i].lnb_flags & OBD_BRW_NOQUOTA) ||
 792                     (lnb[i].lnb_flags & OBD_BRW_SYS_RESOURCE) ||
 793                     !(lnb[i].lnb_flags & OBD_BRW_SYNC))
 794                         declare_flags |= OSD_QID_FORCE;
 795
 796                 if (size == 0) {
 797                         /* first valid lnb */
 798                         offset = lnb[i].lnb_file_offset;
 799                         size = lnb[i].lnb_len;
 800                         continue;
 801                 }
 802                 if (offset + size == lnb[i].lnb_file_offset) {
 803                         /* this lnb is contiguous to the previous one */
 804                         size += lnb[i].lnb_len;
 805                         continue;
 806                 }
 807
 808                 osd_tx_hold_write(oh->ot_tx, obj->oo_dn->dn_object,
 809                                   obj->oo_dn, offset, size);
 810                 /* Estimating space to be consumed by a write is rather
 811                  * complicated with ZFS. As a consequence, we don't account for
 812                  * indirect blocks and just use as a rough estimate the worse
 813                  * case where the old space is being held by a snapshot. Quota
 814                  * overrun will be adjusted once the operation is committed, if
 815                  * required. */
 816                 space += osd_roundup2blocksz(size, offset, blksz);
 817
 818                 offset = lnb[i].lnb_file_offset;
 819                 size = lnb[i].lnb_len;
 820         }
 821
 822         if (size) {
 823                 osd_tx_hold_write(oh->ot_tx, obj->oo_dn->dn_object, obj->oo_dn,
 824                                   offset, size);
 825                 space += osd_roundup2blocksz(size, offset, blksz);
 826         }
 827
 828         /* backend zfs filesystem might be configured to store multiple data
 829          * copies */
 830         space  *= osd->od_os->os_copies;
 831         space   = toqb(space);
 832         CDEBUG(D_QUOTA, "writing %d pages, reserving %lldK of quota space\n",
 833                npages, space);
 834
 835         record_start_io(osd, WRITE, discont_pages);
 836 retry:
 837         /* acquire quota space if needed */
 838         rc = osd_declare_quota(env, osd, obj->oo_attr.la_uid,
 839                                obj->oo_attr.la_gid, obj->oo_attr.la_projid,
 840                                space, oh, &local_flags, declare_flags);
 841
 842         if (!synced && rc == -EDQUOT &&
 843             (local_flags & QUOTA_FL_SYNC) != 0) {
 844                 dt_sync(env, th->th_dev);
 845                 synced = true;
 846                 CDEBUG(D_QUOTA, "retry after sync\n");
 847                 local_flags = 0;
 848                 goto retry;
 849         }
 850
 851         /* we need only to store the overquota flags in the first lnb for
 852          * now, once we support multiple objects BRW, this code needs be
 853          * revised. */
 854         if (local_flags & QUOTA_FL_OVER_USRQUOTA)
 855                 lnb[0].lnb_flags |= OBD_BRW_OVER_USRQUOTA;
 856         if (local_flags & QUOTA_FL_OVER_GRPQUOTA)
 857                 lnb[0].lnb_flags |= OBD_BRW_OVER_GRPQUOTA;
 858 #ifdef ZFS_PROJINHERIT
 859         if (local_flags & QUOTA_FL_OVER_PRJQUOTA)
 860                 lnb[0].lnb_flags |= OBD_BRW_OVER_PRJQUOTA;
 861         if (local_flags & QUOTA_FL_ROOT_PRJQUOTA)
 862                 lnb[0].lnb_flags |= OBD_BRW_ROOT_PRJQUOTA;
 863 #endif
 864
 865         RETURN(rc);
 866 }
 867
 868 /**
 869  * Policy to grow ZFS block size by write pattern.
 870  * For sequential write, it grows block size gradually until it reaches the
 871  * maximum blocksize the dataset can support. Otherwise, it will pick a
 872  * a block size by the writing region of this I/O.
 873  */
 874 static int osd_grow_blocksize(struct osd_object *obj, struct osd_thandle *oh,
 875                               uint64_t start, uint64_t end)
 876 {
 877         struct osd_device       *osd = osd_obj2dev(obj);
 878         dnode_t *dn = obj->oo_dn;
 879         uint32_t                 blksz;
 880         int                      rc = 0;
 881
 882         ENTRY;
 883
 884         if (dn->dn_maxblkid > 0) /* can't change block size */
 885                 GOTO(out, rc);
 886
 887         if (dn->dn_datablksz >= osd->od_max_blksz)
 888                 GOTO(out, rc);
 889
 890         down_write(&obj->oo_guard);
 891
 892         blksz = dn->dn_datablksz;
 893         if (blksz >= osd->od_max_blksz) /* check again after grabbing lock */
 894                 GOTO(out_unlock, rc);
 895
 896         /* now ZFS can support up to 16MB block size, and if the write
 897          * is sequential, it just increases the block size gradually */
 898         if (start <= blksz) { /* sequential */
 899                 blksz = (uint32_t)min_t(uint64_t, osd->od_max_blksz, end);
 900         } else { /* sparse, pick a block size by write region */
 901                 blksz = (uint32_t)min_t(uint64_t, osd->od_max_blksz,
 902                                         end - start);
 903         }
 904
 905         if (!is_power_of_2(blksz))
 906                 blksz = size_roundup_power2(blksz);
 907
 908         if (blksz > dn->dn_datablksz) {
 909                 rc = -dmu_object_set_blocksize(osd->od_os, dn->dn_object,
 910                                                blksz, 0, oh->ot_tx);
 911                 LASSERT(ergo(rc == 0, dn->dn_datablksz >= blksz));
 912                 if (rc < 0)
 913                         CDEBUG(D_INODE, "object "DFID": change block size"
 914                                "%u -> %u error rc = %d\n",
 915                                PFID(lu_object_fid(&obj->oo_dt.do_lu)),
 916                                dn->dn_datablksz, blksz, rc);
 917         }
 918         EXIT;
 919 out_unlock:
 920         up_write(&obj->oo_guard);
 921 out:
 922         return rc;
 923 }
 924
 925 static void osd_evict_dbufs_after_write(struct osd_object *obj,
 926                                         loff_t off, ssize_t len)
 927 {
 928         dmu_buf_t **dbp;
 929         int i, rc, numbufs;
 930
 931         rc = -dmu_buf_hold_array_by_bonus(&obj->oo_dn->dn_bonus->db, off, len,
 932                                           TRUE, osd_0copy_tag, &numbufs, &dbp);
 933         if (unlikely(rc))
 934                 return;
 935
 936         for (i = 0; i < numbufs; i++)
 937                 dbuf_set_pending_evict(dbp[i]);
 938
 939         dmu_buf_rele_array(dbp, numbufs, osd_0copy_tag);
 940 }
 941
 942 static int osd_write_commit(const struct lu_env *env, struct dt_object *dt,
 943                         struct niobuf_local *lnb, int npages,
 944                         struct thandle *th, __u64 user_size)
 945 {
 946         struct osd_object  *obj  = osd_dt_obj(dt);
 947         struct osd_device  *osd = osd_obj2dev(obj);
 948         struct osd_thandle *oh;
 949         uint64_t            new_size = 0;
 950         int                 i, abufsz, rc = 0, drop_cache = 0;
 951         unsigned long      iosize = 0;
 952         ENTRY;
 953
 954         LASSERT(dt_object_exists(dt));
 955         LASSERT(obj->oo_dn);
 956
 957         LASSERT(th != NULL);
 958         oh = container_of(th, struct osd_thandle, ot_super);
 959
 960         /* adjust block size. Assume the buffers are sorted. */
 961         (void)osd_grow_blocksize(obj, oh, lnb[0].lnb_file_offset,
 962                                  lnb[npages - 1].lnb_file_offset +
 963                                  lnb[npages - 1].lnb_len);
 964
 965         if (obj->oo_attr.la_size >= osd->od_readcache_max_filesize ||
 966             lnb[npages - 1].lnb_file_offset + lnb[npages - 1].lnb_len >=
 967             osd->od_readcache_max_filesize)
 968                 drop_cache = 1;
 969
 970         if (CFS_FAIL_CHECK(OBD_FAIL_OST_MAPBLK_ENOSPC))
 971                 RETURN(-ENOSPC);
 972
 973         /* if la_size is already bigger than specified user_size,
 974          * ignore user_size
 975          */
 976         if (obj->oo_attr.la_size > user_size)
 977                 user_size = 0;
 978
 979         /* LU-8791: take oo_guard to avoid the deadlock that changing block
 980          * size and assigning arcbuf take place at the same time.
 981          *
 982          * Thread 1:
 983          * osd_write_commit()
 984          *  -> osd_grow_blocksize() with osd_object::oo_guard held
 985          *   -> dmu_object_set_blocksize()
 986          *    -> dnode_set_blksz(), with dnode_t::dn_struct_rwlock
 987          *       write lock held
 988          *     -> dbuf_new_size()
 989          *      -> dmu_buf_will_dirty()
 990          *       -> dbuf_read()
 991          *        -> wait for the dbuf state to change
 992          * Thread 2:
 993          * osd_write_commit()
 994          *  -> dmu_assign_arcbuf()
 995          *   -> dbuf_assign_arcbuf(), set dbuf state to DB_FILL
 996          *    -> dbuf_dirty()
 997          *     -> try to hold the read lock of dnode_t::dn_struct_rwlock
 998          *
 999          * By taking the read lock, it can avoid thread 2 to enter into the
1000          * critical section of assigning the arcbuf, while thread 1 is
1001          * changing the block size.
1002          */
1003         down_read(&obj->oo_guard);
1004         if (obj->oo_destroyed) {
1005                 up_read(&obj->oo_guard);
1006                 RETURN(-ENOENT);
1007         }
1008
1009         for (i = 0; i < npages; i++) {
1010                 CDEBUG(D_INODE, "write %u bytes at %u\n",
1011                         (unsigned) lnb[i].lnb_len,
1012                         (unsigned) lnb[i].lnb_file_offset);
1013
1014                 if (lnb[i].lnb_rc) {
1015                         /* ENOSPC, network RPC error, etc.
1016                          * Unlike ldiskfs, zfs allocates new blocks on rewrite,
1017                          * so we skip this page if lnb_rc is set to -ENOSPC */
1018                         CDEBUG(D_INODE, "obj "DFID": skipping lnb[%u]: rc=%d\n",
1019                                 PFID(lu_object_fid(&dt->do_lu)), i,
1020                                 lnb[i].lnb_rc);
1021                         continue;
1022                 }
1023
1024                 if (new_size < lnb[i].lnb_file_offset + lnb[i].lnb_len)
1025                         new_size = lnb[i].lnb_file_offset + lnb[i].lnb_len;
1026                 if (lnb[i].lnb_page == NULL)
1027                         continue;
1028
1029                 if (lnb[i].lnb_page->mapping == (void *)obj) {
1030                         osd_dmu_write(osd, obj->oo_dn, lnb[i].lnb_file_offset,
1031                                       lnb[i].lnb_len, kmap(lnb[i].lnb_page) +
1032                                       lnb[i].lnb_page_offset, oh->ot_tx);
1033                         kunmap(lnb[i].lnb_page);
1034                         iosize += lnb[i].lnb_len;
1035                         abufsz = lnb[i].lnb_len; /* to drop cache below */
1036                 } else if (lnb[i].lnb_data) {
1037                         int j, apages;
1038                         LASSERT(((unsigned long)lnb[i].lnb_data & 1) == 0);
1039                         /* buffer loaned for zerocopy, try to use it.
1040                          * notice that dmu_assign_arcbuf() is smart
1041                          * enough to recognize changed blocksize
1042                          * in this case it fallbacks to dmu_write() */
1043                         abufsz = arc_buf_size(lnb[i].lnb_data);
1044                         LASSERT(abufsz & PAGE_MASK);
1045                         apages = abufsz >> PAGE_SHIFT;
1046                         LASSERT(i + apages <= npages);
1047                         /* these references to pages must be invalidated
1048                          * to prevent access in osd_bufs_put() */
1049                         for (j = 0; j < apages; j++)
1050                                 lnb[i + j].lnb_page = NULL;
1051                         dmu_assign_arcbuf(&obj->oo_dn->dn_bonus->db,
1052                                           lnb[i].lnb_file_offset,
1053                                           lnb[i].lnb_data, oh->ot_tx);
1054                         /* drop the reference, otherwise osd_put_bufs()
1055                          * will be releasing it - bad! */
1056                         lnb[i].lnb_data = NULL;
1057                         atomic_dec(&osd->od_zerocopy_loan);
1058                         iosize += abufsz;
1059                 } else {
1060                         /* we don't want to deal with cache if nothing
1061                          * has been send to ZFS at this step */
1062                         continue;
1063                 }
1064
1065                 if (!drop_cache)
1066                         continue;
1067
1068                 /* we have to mark dbufs for eviction here because
1069                  * dmu_assign_arcbuf() may create a new dbuf for
1070                  * loaned abuf */
1071                 osd_evict_dbufs_after_write(obj, lnb[i].lnb_file_offset,
1072                                             abufsz);
1073         }
1074
1075         if (unlikely(new_size == 0)) {
1076                 /* no pages to write, no transno is needed */
1077                 th->th_local = 1;
1078                 /* it is important to return 0 even when all lnb_rc == -ENOSPC
1079                  * since ofd_commitrw_write() retries several times on ENOSPC */
1080                 up_read(&obj->oo_guard);
1081                 record_end_io(osd, WRITE, 0, 0, 0);
1082                 RETURN(0);
1083         }
1084
1085         /* if file has grown, take user_size into account */
1086         if (user_size && new_size > user_size)
1087                 new_size = user_size;
1088         write_lock(&obj->oo_attr_lock);
1089         if (obj->oo_attr.la_size < new_size) {
1090                 obj->oo_attr.la_size = new_size;
1091                 write_unlock(&obj->oo_attr_lock);
1092                 /* osd_object_sa_update() will be copying directly from
1093                  * oo_attr into dbuf. any update within a single txg will copy
1094                  * the most actual */
1095                 rc = osd_object_sa_update(obj, SA_ZPL_SIZE(osd),
1096                                           &obj->oo_attr.la_size, 8, oh);
1097         } else {
1098                 write_unlock(&obj->oo_attr_lock);
1099         }
1100
1101         up_read(&obj->oo_guard);
1102
1103         record_end_io(osd, WRITE, 0, iosize, npages);
1104
1105         RETURN(rc);
1106 }
1107
1108 static int osd_read_prep(const struct lu_env *env, struct dt_object *dt,
1109                         struct niobuf_local *lnb, int npages)
1110 {
1111         struct osd_object *obj  = osd_dt_obj(dt);
1112         int                i;
1113         loff_t             eof;
1114
1115         LASSERT(dt_object_exists(dt));
1116         LASSERT(obj->oo_dn);
1117
1118         read_lock(&obj->oo_attr_lock);
1119         eof = obj->oo_attr.la_size;
1120         read_unlock(&obj->oo_attr_lock);
1121
1122         for (i = 0; i < npages; i++) {
1123                 if (unlikely(lnb[i].lnb_rc < 0))
1124                         continue;
1125
1126                 lnb[i].lnb_rc = lnb[i].lnb_len;
1127
1128                 if (lnb[i].lnb_file_offset + lnb[i].lnb_len >= eof) {
1129                         /* send complete pages all the time */
1130                         if (eof <= lnb[i].lnb_file_offset)
1131                                 lnb[i].lnb_rc = 0;
1132
1133                         /* all subsequent rc should be 0 */
1134                         while (++i < npages)
1135                                 lnb[i].lnb_rc = 0;
1136                         break;
1137                 }
1138         }
1139
1140         return 0;
1141 }
1142
1143 /*
1144  * Punch/truncate an object
1145  *
1146  *      IN:     db  - dmu_buf of the object to free data in.
1147  *              off - start of section to free.
1148  *              len - length of section to free (DMU_OBJECT_END => to EOF).
1149  *
1150  *      RETURN: 0 if success
1151  *              error code if failure
1152  *
1153  * The transaction passed to this routine must have
1154  * dmu_tx_hold_sa() and if off < size, dmu_tx_hold_free()
1155  * called and then assigned to a transaction group.
1156  */
1157 static int __osd_object_punch(struct osd_object *obj, objset_t *os,
1158                               dmu_tx_t *tx, uint64_t off, uint64_t len)
1159 {
1160         dnode_t *dn = obj->oo_dn;
1161         uint64_t size = obj->oo_attr.la_size;
1162         int rc = 0;
1163
1164         /* Assert that the transaction has been assigned to a
1165            transaction group. */
1166         LASSERT(tx->tx_txg != 0);
1167         /*
1168          * Nothing to do if file already at desired length.
1169          */
1170         if (len == DMU_OBJECT_END && size == off)
1171                 return 0;
1172
1173         /* if object holds encrypted content, we need to make sure we truncate
1174          * on an encryption unit boundary, or subsequent reads will get
1175          * corrupted content
1176          */
1177         if (len != DMU_OBJECT_END)
1178                 len -= LUSTRE_ENCRYPTION_UNIT_SIZE -
1179                         (off & ~LUSTRE_ENCRYPTION_MASK);
1180         if (obj->oo_lma_flags & LUSTRE_ENCRYPT_FL &&
1181             off & ~LUSTRE_ENCRYPTION_MASK)
1182                 off = (off & LUSTRE_ENCRYPTION_MASK) +
1183                         LUSTRE_ENCRYPTION_UNIT_SIZE;
1184
1185
1186         /* XXX: dnode_free_range() can be used to save on dnode lookup */
1187         if (off < size)
1188                 dmu_free_range(os, dn->dn_object, off, len, tx);
1189
1190         return rc;
1191 }
1192
1193 static int osd_punch(const struct lu_env *env, struct dt_object *dt,
1194                         __u64 start, __u64 end, struct thandle *th)
1195 {
1196         struct osd_object  *obj = osd_dt_obj(dt);
1197         struct osd_device  *osd = osd_obj2dev(obj);
1198         struct osd_thandle *oh;
1199         __u64               len;
1200         int                 rc = 0;
1201         ENTRY;
1202
1203         LASSERT(dt_object_exists(dt));
1204         LASSERT(osd_invariant(obj));
1205
1206         LASSERT(th != NULL);
1207         oh = container_of(th, struct osd_thandle, ot_super);
1208
1209         write_lock(&obj->oo_attr_lock);
1210         /* truncate */
1211         if (end == OBD_OBJECT_EOF || end >= obj->oo_attr.la_size)
1212                 len = DMU_OBJECT_END;
1213         else
1214                 len = end - start;
1215         write_unlock(&obj->oo_attr_lock);
1216
1217         down_read(&obj->oo_guard);
1218         if (obj->oo_destroyed)
1219                 GOTO(out, rc = -ENOENT);
1220
1221         rc = __osd_object_punch(obj, osd->od_os, oh->ot_tx, start, len);
1222
1223         /* set new size */
1224         if (len == DMU_OBJECT_END) {
1225                 write_lock(&obj->oo_attr_lock);
1226                 obj->oo_attr.la_size = start;
1227                 write_unlock(&obj->oo_attr_lock);
1228                 rc = osd_object_sa_update(obj, SA_ZPL_SIZE(osd),
1229                                           &obj->oo_attr.la_size, 8, oh);
1230         }
1231 out:
1232         up_read(&obj->oo_guard);
1233         RETURN(rc);
1234 }
1235
1236 static int osd_declare_punch(const struct lu_env *env, struct dt_object *dt,
1237                         __u64 start, __u64 end, struct thandle *handle)
1238 {
1239         struct osd_object  *obj = osd_dt_obj(dt);
1240         struct osd_device  *osd = osd_obj2dev(obj);
1241         struct osd_thandle *oh;
1242         __u64               len;
1243         ENTRY;
1244
1245         oh = container_of(handle, struct osd_thandle, ot_super);
1246
1247         read_lock(&obj->oo_attr_lock);
1248         if (end == OBD_OBJECT_EOF || end >= obj->oo_attr.la_size)
1249                 len = DMU_OBJECT_END;
1250         else
1251                 len = end - start;
1252
1253         /* declare we'll free some blocks ... */
1254         /* if object holds encrypted content, we need to make sure we truncate
1255          * on an encryption unit boundary, or subsequent reads will get
1256          * corrupted content
1257          */
1258         if (obj->oo_lma_flags & LUSTRE_ENCRYPT_FL &&
1259             start & ~LUSTRE_ENCRYPTION_MASK)
1260                 start = (start & LUSTRE_ENCRYPTION_MASK) +
1261                         LUSTRE_ENCRYPTION_UNIT_SIZE;
1262         if (start < obj->oo_attr.la_size) {
1263                 read_unlock(&obj->oo_attr_lock);
1264                 dmu_tx_mark_netfree(oh->ot_tx);
1265                 dmu_tx_hold_free(oh->ot_tx, obj->oo_dn->dn_object, start, len);
1266         } else {
1267                 read_unlock(&obj->oo_attr_lock);
1268         }
1269
1270         RETURN(osd_declare_quota(env, osd, obj->oo_attr.la_uid,
1271                                  obj->oo_attr.la_gid, obj->oo_attr.la_projid,
1272                                  0, oh, NULL, OSD_QID_BLK));
1273 }
1274
1275 static int osd_ladvise(const struct lu_env *env, struct dt_object *dt,
1276                        __u64 start, __u64 end, enum lu_ladvise_type advice)
1277 {
1278         int     rc;
1279         ENTRY;
1280
1281         switch (advice) {
1282         default:
1283                 rc = -ENOTSUPP;
1284                 break;
1285         }
1286
1287         RETURN(rc);
1288 }
1289
1290 static int osd_fallocate(const struct lu_env *env, struct dt_object *dt,
1291                          __u64 start, __u64 end, int mode, struct thandle *th)
1292 {
1293         int rc = -EOPNOTSUPP;
1294         ENTRY;
1295
1296          /*
1297           * space preallocation is not supported for ZFS
1298           * Returns -EOPNOTSUPP for now
1299           */
1300         RETURN(rc);
1301 }
1302
1303 static int osd_declare_fallocate(const struct lu_env *env,
1304                                  struct dt_object *dt, __u64 start, __u64 end,
1305                                  int mode, struct thandle *th)
1306 {
1307         int rc = -EOPNOTSUPP;
1308         ENTRY;
1309
1310          /*
1311           * space preallocation is not supported for ZFS
1312           * Returns -EOPNOTSUPP for now
1313           */
1314         RETURN(rc);
1315 }
1316
1317 static loff_t osd_lseek(const struct lu_env *env, struct dt_object *dt,
1318                         loff_t offset, int whence)
1319 {
1320         struct osd_object *obj = osd_dt_obj(dt);
1321         struct osd_device *osd = osd_obj2dev(obj);
1322         uint64_t size = obj->oo_attr.la_size;
1323         uint64_t result = offset;
1324         int rc;
1325         boolean_t hole = whence == SEEK_HOLE;
1326
1327         ENTRY;
1328
1329         LASSERT(dt_object_exists(dt));
1330         LASSERT(osd_invariant(obj));
1331         LASSERT(offset >= 0);
1332
1333         /* for SEEK_HOLE treat 'offset' beyond the end of file as in real
1334          * hole. LOV to decide after all if that real hole or not.
1335          */
1336         if (offset >= size)
1337                 RETURN(hole ? offset : -ENXIO);
1338
1339         /* Currently ZFS reports no valid DATA offset if object has dirty data
1340          * and we cannot just switch to generic way with reporting DATA on all
1341          * file offsets and HOLE beyond end of file, because we may get HOLE
1342          * reported correctly at some offset inside file then DATA will find
1343          * dirty state and be reported also at that offset by generic approach.
1344          * This is because for HOLE report ZFS doesn't check dirty state but
1345          * does for DATA.
1346          * The only way to get reliable results is to call txg_wait_synced()
1347          * when ZFS reports EBUSY result and repeat lseek call and that is
1348          * controlled via od_sync_on_lseek option.
1349          */
1350         if (!osd->od_sync_on_lseek)
1351                 result = hole ? size : offset;
1352
1353 again:
1354         rc = osd_dmu_offset_next(osd->od_os, obj->oo_dn->dn_object, hole,
1355                                  &result);
1356         /* dirty inode, lseek result is unreliable without sync */
1357         if (rc == EBUSY) {
1358                 txg_wait_synced(dmu_objset_pool(osd->od_os), 0ULL);
1359                 goto again;
1360         }
1361
1362         if (rc == ESRCH)
1363                 RETURN(-ENXIO);
1364
1365         /* ZFS is not exported all needed function, so fall back to the
1366          * generic logic: for HOLE return file size, for DATA return
1367          * the current offset
1368          */
1369         if (rc == EOPNOTSUPP)
1370                 result = hole ? size : offset;
1371         else if (rc)
1372                 return -rc;
1373
1374         /* dmu_offset_next() only works on whole blocks so may return SEEK_HOLE
1375          * result as end of the last block instead of logical EOF which we need
1376          */
1377         if (result > size)
1378                 result = size;
1379
1380         RETURN(result);
1381 }
1382
1383 const struct dt_body_operations osd_body_ops = {
1384         .dbo_read                       = osd_read,
1385         .dbo_declare_write              = osd_declare_write,
1386         .dbo_write                      = osd_write,
1387         .dbo_bufs_get                   = osd_bufs_get,
1388         .dbo_bufs_put                   = osd_bufs_put,
1389         .dbo_write_prep                 = osd_write_prep,
1390         .dbo_declare_write_commit       = osd_declare_write_commit,
1391         .dbo_write_commit               = osd_write_commit,
1392         .dbo_read_prep                  = osd_read_prep,
1393         .dbo_declare_punch              = osd_declare_punch,
1394         .dbo_punch                      = osd_punch,
1395         .dbo_ladvise                    = osd_ladvise,
1396         .dbo_declare_fallocate          = osd_declare_fallocate,
1397         .dbo_fallocate                  = osd_fallocate,
1398         .dbo_lseek                      = osd_lseek,
1399 };
1400
1401 const struct dt_body_operations osd_body_scrub_ops = {
1402         .dbo_read                       = osd_read_no_record,
1403         .dbo_declare_write              = osd_declare_write,
1404         .dbo_write                      = osd_write,
1405 };