fs/exofs/ore.c

   1 /*
   2  * Copyright (C) 2005, 2006
   3  * Avishay Traeger (avishay@gmail.com)
   4  * Copyright (C) 2008, 2009
   5  * Boaz Harrosh <bharrosh@panasas.com>
   6  *
   7  * This file is part of exofs.
   8  *
   9  * exofs is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation.  Since it is based on ext2, and the only
  12  * valid version of GPL for the Linux kernel is version 2, the only valid
  13  * version of GPL for exofs is version 2.
  14  *
  15  * exofs is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with exofs; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  23  */
  24
  25 #include <linux/slab.h>
  26 #include <asm/div64.h>
  27
  28 #include <scsi/osd_ore.h>
  29
  30 #define ORE_ERR(fmt, a...) printk(KERN_ERR "ore: " fmt, ##a)
  31
  32 #ifdef CONFIG_EXOFS_DEBUG
  33 #define ORE_DBGMSG(fmt, a...) \
  34         printk(KERN_NOTICE "ore @%s:%d: " fmt, __func__, __LINE__, ##a)
  35 #else
  36 #define ORE_DBGMSG(fmt, a...) \
  37         do { if (0) printk(fmt, ##a); } while (0)
  38 #endif
  39
  40 /* u64 has problems with printk this will cast it to unsigned long long */
  41 #define _LLU(x) (unsigned long long)(x)
  42
  43 #define ORE_DBGMSG2(M...) do {} while (0)
  44 /* #define ORE_DBGMSG2 ORE_DBGMSG */
  45
  46 MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>");
  47 MODULE_DESCRIPTION("Objects Raid Engine ore.ko");
  48 MODULE_LICENSE("GPL");
  49
  50 static u8 *_ios_cred(struct ore_io_state *ios, unsigned index)
  51 {
  52         return ios->comps->comps[index & ios->comps->single_comp].cred;
  53 }
  54
  55 static struct osd_obj_id *_ios_obj(struct ore_io_state *ios, unsigned index)
  56 {
  57         return &ios->comps->comps[index & ios->comps->single_comp].obj;
  58 }
  59
  60 static struct osd_dev *_ios_od(struct ore_io_state *ios, unsigned index)
  61 {
  62         return ios->comps->ods[index];
  63 }
  64
  65 int  ore_get_rw_state(struct ore_layout *layout, struct ore_components *comps,
  66                       bool is_reading, u64 offset, u64 length,
  67                       struct ore_io_state **pios)
  68 {
  69         struct ore_io_state *ios;
  70
  71         /*TODO: Maybe use kmem_cach per sbi of size
  72          * exofs_io_state_size(layout->s_numdevs)
  73          */
  74         ios = kzalloc(ore_io_state_size(comps->numdevs), GFP_KERNEL);
  75         if (unlikely(!ios)) {
  76                 ORE_DBGMSG("Failed kzalloc bytes=%d\n",
  77                              ore_io_state_size(comps->numdevs));
  78                 *pios = NULL;
  79                 return -ENOMEM;
  80         }
  81
  82         ios->layout = layout;
  83         ios->comps = comps;
  84         ios->offset = offset;
  85         ios->length = length;
  86         ios->reading = is_reading;
  87
  88         *pios = ios;
  89         return 0;
  90 }
  91 EXPORT_SYMBOL(ore_get_rw_state);
  92
  93 int  ore_get_io_state(struct ore_layout *layout, struct ore_components *comps,
  94                       struct ore_io_state **ios)
  95 {
  96         return ore_get_rw_state(layout, comps, true, 0, 0, ios);
  97 }
  98 EXPORT_SYMBOL(ore_get_io_state);
  99
 100 void ore_put_io_state(struct ore_io_state *ios)
 101 {
 102         if (ios) {
 103                 unsigned i;
 104
 105                 for (i = 0; i < ios->numdevs; i++) {
 106                         struct ore_per_dev_state *per_dev = &ios->per_dev[i];
 107
 108                         if (per_dev->or)
 109                                 osd_end_request(per_dev->or);
 110                         if (per_dev->bio)
 111                                 bio_put(per_dev->bio);
 112                 }
 113
 114                 kfree(ios);
 115         }
 116 }
 117 EXPORT_SYMBOL(ore_put_io_state);
 118
 119 static void _sync_done(struct ore_io_state *ios, void *p)
 120 {
 121         struct completion *waiting = p;
 122
 123         complete(waiting);
 124 }
 125
 126 static void _last_io(struct kref *kref)
 127 {
 128         struct ore_io_state *ios = container_of(
 129                                         kref, struct ore_io_state, kref);
 130
 131         ios->done(ios, ios->private);
 132 }
 133
 134 static void _done_io(struct osd_request *or, void *p)
 135 {
 136         struct ore_io_state *ios = p;
 137
 138         kref_put(&ios->kref, _last_io);
 139 }
 140
 141 static int ore_io_execute(struct ore_io_state *ios)
 142 {
 143         DECLARE_COMPLETION_ONSTACK(wait);
 144         bool sync = (ios->done == NULL);
 145         int i, ret;
 146
 147         if (sync) {
 148                 ios->done = _sync_done;
 149                 ios->private = &wait;
 150         }
 151
 152         for (i = 0; i < ios->numdevs; i++) {
 153                 struct osd_request *or = ios->per_dev[i].or;
 154                 if (unlikely(!or))
 155                         continue;
 156
 157                 ret = osd_finalize_request(or, 0, _ios_cred(ios, i), NULL);
 158                 if (unlikely(ret)) {
 159                         ORE_DBGMSG("Failed to osd_finalize_request() => %d\n",
 160                                      ret);
 161                         return ret;
 162                 }
 163         }
 164
 165         kref_init(&ios->kref);
 166
 167         for (i = 0; i < ios->numdevs; i++) {
 168                 struct osd_request *or = ios->per_dev[i].or;
 169                 if (unlikely(!or))
 170                         continue;
 171
 172                 kref_get(&ios->kref);
 173                 osd_execute_request_async(or, _done_io, ios);
 174         }
 175
 176         kref_put(&ios->kref, _last_io);
 177         ret = 0;
 178
 179         if (sync) {
 180                 wait_for_completion(&wait);
 181                 ret = ore_check_io(ios, NULL);
 182         }
 183         return ret;
 184 }
 185
 186 static void _clear_bio(struct bio *bio)
 187 {
 188         struct bio_vec *bv;
 189         unsigned i;
 190
 191         __bio_for_each_segment(bv, bio, i, 0) {
 192                 unsigned this_count = bv->bv_len;
 193
 194                 if (likely(PAGE_SIZE == this_count))
 195                         clear_highpage(bv->bv_page);
 196                 else
 197                         zero_user(bv->bv_page, bv->bv_offset, this_count);
 198         }
 199 }
 200
 201 int ore_check_io(struct ore_io_state *ios, u64 *resid)
 202 {
 203         enum osd_err_priority acumulated_osd_err = 0;
 204         int acumulated_lin_err = 0;
 205         int i;
 206
 207         for (i = 0; i < ios->numdevs; i++) {
 208                 struct osd_sense_info osi;
 209                 struct osd_request *or = ios->per_dev[i].or;
 210                 int ret;
 211
 212                 if (unlikely(!or))
 213                         continue;
 214
 215                 ret = osd_req_decode_sense(or, &osi);
 216                 if (likely(!ret))
 217                         continue;
 218
 219                 if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) {
 220                         /* start read offset passed endof file */
 221                         _clear_bio(ios->per_dev[i].bio);
 222                         ORE_DBGMSG("start read offset passed end of file "
 223                                 "offset=0x%llx, length=0x%llx\n",
 224                                 _LLU(ios->per_dev[i].offset),
 225                                 _LLU(ios->per_dev[i].length));
 226
 227                         continue; /* we recovered */
 228                 }
 229
 230                 if (osi.osd_err_pri >= acumulated_osd_err) {
 231                         acumulated_osd_err = osi.osd_err_pri;
 232                         acumulated_lin_err = ret;
 233                 }
 234         }
 235
 236         /* TODO: raid specific residual calculations */
 237         if (resid) {
 238                 if (likely(!acumulated_lin_err))
 239                         *resid = 0;
 240                 else
 241                         *resid = ios->length;
 242         }
 243
 244         return acumulated_lin_err;
 245 }
 246 EXPORT_SYMBOL(ore_check_io);
 247
 248 /*
 249  * L - logical offset into the file
 250  *
 251  * U - The number of bytes in a stripe within a group
 252  *
 253  *      U = stripe_unit * group_width
 254  *
 255  * T - The number of bytes striped within a group of component objects
 256  *     (before advancing to the next group)
 257  *
 258  *      T = stripe_unit * group_width * group_depth
 259  *
 260  * S - The number of bytes striped across all component objects
 261  *     before the pattern repeats
 262  *
 263  *      S = stripe_unit * group_width * group_depth * group_count
 264  *
 265  * M - The "major" (i.e., across all components) stripe number
 266  *
 267  *      M = L / S
 268  *
 269  * G - Counts the groups from the beginning of the major stripe
 270  *
 271  *      G = (L - (M * S)) / T   [or (L % S) / T]
 272  *
 273  * H - The byte offset within the group
 274  *
 275  *      H = (L - (M * S)) % T   [or (L % S) % T]
 276  *
 277  * N - The "minor" (i.e., across the group) stripe number
 278  *
 279  *      N = H / U
 280  *
 281  * C - The component index coresponding to L
 282  *
 283  *      C = (H - (N * U)) / stripe_unit + G * group_width
 284  *      [or (L % U) / stripe_unit + G * group_width]
 285  *
 286  * O - The component offset coresponding to L
 287  *
 288  *      O = L % stripe_unit + N * stripe_unit + M * group_depth * stripe_unit
 289  */
 290 struct _striping_info {
 291         u64 obj_offset;
 292         u64 group_length;
 293         u64 M; /* for truncate */
 294         unsigned dev;
 295         unsigned unit_off;
 296 };
 297
 298 static void _calc_stripe_info(struct ore_layout *layout, u64 file_offset,
 299                               struct _striping_info *si)
 300 {
 301         u32     stripe_unit = layout->stripe_unit;
 302         u32     group_width = layout->group_width;
 303         u64     group_depth = layout->group_depth;
 304
 305         u32     U = stripe_unit * group_width;
 306         u64     T = U * group_depth;
 307         u64     S = T * layout->group_count;
 308         u64     M = div64_u64(file_offset, S);
 309
 310         /*
 311         G = (L - (M * S)) / T
 312         H = (L - (M * S)) % T
 313         */
 314         u64     LmodS = file_offset - M * S;
 315         u32     G = div64_u64(LmodS, T);
 316         u64     H = LmodS - G * T;
 317
 318         u32     N = div_u64(H, U);
 319
 320         /* "H - (N * U)" is just "H % U" so it's bound to u32 */
 321         si->dev = (u32)(H - (N * U)) / stripe_unit + G * group_width;
 322         si->dev *= layout->mirrors_p1;
 323
 324         div_u64_rem(file_offset, stripe_unit, &si->unit_off);
 325
 326         si->obj_offset = si->unit_off + (N * stripe_unit) +
 327                                   (M * group_depth * stripe_unit);
 328
 329         si->group_length = T - H;
 330         si->M = M;
 331 }
 332
 333 static int _add_stripe_unit(struct ore_io_state *ios,  unsigned *cur_pg,
 334                 unsigned pgbase, struct ore_per_dev_state *per_dev,
 335                 int cur_len)
 336 {
 337         unsigned pg = *cur_pg;
 338         struct request_queue *q =
 339                         osd_request_queue(_ios_od(ios, per_dev->dev));
 340
 341         per_dev->length += cur_len;
 342
 343         if (per_dev->bio == NULL) {
 344                 unsigned pages_in_stripe = ios->layout->group_width *
 345                                         (ios->layout->stripe_unit / PAGE_SIZE);
 346                 unsigned bio_size = (ios->nr_pages + pages_in_stripe) /
 347                                                 ios->layout->group_width;
 348
 349                 per_dev->bio = bio_kmalloc(GFP_KERNEL, bio_size);
 350                 if (unlikely(!per_dev->bio)) {
 351                         ORE_DBGMSG("Failed to allocate BIO size=%u\n",
 352                                      bio_size);
 353                         return -ENOMEM;
 354                 }
 355         }
 356
 357         while (cur_len > 0) {
 358                 unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
 359                 unsigned added_len;
 360
 361                 BUG_ON(ios->nr_pages <= pg);
 362                 cur_len -= pglen;
 363
 364                 added_len = bio_add_pc_page(q, per_dev->bio, ios->pages[pg],
 365                                             pglen, pgbase);
 366                 if (unlikely(pglen != added_len))
 367                         return -ENOMEM;
 368                 pgbase = 0;
 369                 ++pg;
 370         }
 371         BUG_ON(cur_len);
 372
 373         *cur_pg = pg;
 374         return 0;
 375 }
 376
 377 static int _prepare_one_group(struct ore_io_state *ios, u64 length,
 378                               struct _striping_info *si)
 379 {
 380         unsigned stripe_unit = ios->layout->stripe_unit;
 381         unsigned mirrors_p1 = ios->layout->mirrors_p1;
 382         unsigned devs_in_group = ios->layout->group_width * mirrors_p1;
 383         unsigned dev = si->dev;
 384         unsigned first_dev = dev - (dev % devs_in_group);
 385         unsigned max_comp = ios->numdevs ? ios->numdevs - mirrors_p1 : 0;
 386         unsigned cur_pg = ios->pages_consumed;
 387         int ret = 0;
 388
 389         while (length) {
 390                 struct ore_per_dev_state *per_dev = &ios->per_dev[dev];
 391                 unsigned cur_len, page_off = 0;
 392
 393                 if (!per_dev->length) {
 394                         per_dev->dev = dev;
 395                         if (dev < si->dev) {
 396                                 per_dev->offset = si->obj_offset + stripe_unit -
 397                                                                    si->unit_off;
 398                                 cur_len = stripe_unit;
 399                         } else if (dev == si->dev) {
 400                                 per_dev->offset = si->obj_offset;
 401                                 cur_len = stripe_unit - si->unit_off;
 402                                 page_off = si->unit_off & ~PAGE_MASK;
 403                                 BUG_ON(page_off && (page_off != ios->pgbase));
 404                         } else { /* dev > si->dev */
 405                                 per_dev->offset = si->obj_offset - si->unit_off;
 406                                 cur_len = stripe_unit;
 407                         }
 408
 409                         if (max_comp < dev)
 410                                 max_comp = dev;
 411                 } else {
 412                         cur_len = stripe_unit;
 413                 }
 414                 if (cur_len >= length)
 415                         cur_len = length;
 416
 417                 ret = _add_stripe_unit(ios, &cur_pg, page_off , per_dev,
 418                                        cur_len);
 419                 if (unlikely(ret))
 420                         goto out;
 421
 422                 dev += mirrors_p1;
 423                 dev = (dev % devs_in_group) + first_dev;
 424
 425                 length -= cur_len;
 426         }
 427 out:
 428         ios->numdevs = max_comp + mirrors_p1;
 429         ios->pages_consumed = cur_pg;
 430         return ret;
 431 }
 432
 433 static int _prepare_for_striping(struct ore_io_state *ios)
 434 {
 435         u64 length = ios->length;
 436         u64 offset = ios->offset;
 437         struct _striping_info si;
 438         int ret = 0;
 439
 440         if (!ios->pages) {
 441                 if (ios->kern_buff) {
 442                         struct ore_per_dev_state *per_dev = &ios->per_dev[0];
 443
 444                         _calc_stripe_info(ios->layout, ios->offset, &si);
 445                         per_dev->offset = si.obj_offset;
 446                         per_dev->dev = si.dev;
 447
 448                         /* no cross device without page array */
 449                         BUG_ON((ios->layout->group_width > 1) &&
 450                                (si.unit_off + ios->length >
 451                                 ios->layout->stripe_unit));
 452                 }
 453                 ios->numdevs = ios->layout->mirrors_p1;
 454                 return 0;
 455         }
 456
 457         while (length) {
 458                 _calc_stripe_info(ios->layout, offset, &si);
 459
 460                 if (length < si.group_length)
 461                         si.group_length = length;
 462
 463                 ret = _prepare_one_group(ios, si.group_length, &si);
 464                 if (unlikely(ret))
 465                         goto out;
 466
 467                 offset += si.group_length;
 468                 length -= si.group_length;
 469         }
 470
 471 out:
 472         return ret;
 473 }
 474
 475 int ore_create(struct ore_io_state *ios)
 476 {
 477         int i, ret;
 478
 479         for (i = 0; i < ios->comps->numdevs; i++) {
 480                 struct osd_request *or;
 481
 482                 or = osd_start_request(_ios_od(ios, i), GFP_KERNEL);
 483                 if (unlikely(!or)) {
 484                         ORE_ERR("%s: osd_start_request failed\n", __func__);
 485                         ret = -ENOMEM;
 486                         goto out;
 487                 }
 488                 ios->per_dev[i].or = or;
 489                 ios->numdevs++;
 490
 491                 osd_req_create_object(or, _ios_obj(ios, i));
 492         }
 493         ret = ore_io_execute(ios);
 494
 495 out:
 496         return ret;
 497 }
 498 EXPORT_SYMBOL(ore_create);
 499
 500 int ore_remove(struct ore_io_state *ios)
 501 {
 502         int i, ret;
 503
 504         for (i = 0; i < ios->comps->numdevs; i++) {
 505                 struct osd_request *or;
 506
 507                 or = osd_start_request(_ios_od(ios, i), GFP_KERNEL);
 508                 if (unlikely(!or)) {
 509                         ORE_ERR("%s: osd_start_request failed\n", __func__);
 510                         ret = -ENOMEM;
 511                         goto out;
 512                 }
 513                 ios->per_dev[i].or = or;
 514                 ios->numdevs++;
 515
 516                 osd_req_remove_object(or, _ios_obj(ios, i));
 517         }
 518         ret = ore_io_execute(ios);
 519
 520 out:
 521         return ret;
 522 }
 523 EXPORT_SYMBOL(ore_remove);
 524
 525 static int _write_mirror(struct ore_io_state *ios, int cur_comp)
 526 {
 527         struct ore_per_dev_state *master_dev = &ios->per_dev[cur_comp];
 528         unsigned dev = ios->per_dev[cur_comp].dev;
 529         unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
 530         int ret = 0;
 531
 532         if (ios->pages && !master_dev->length)
 533                 return 0; /* Just an empty slot */
 534
 535         for (; cur_comp < last_comp; ++cur_comp, ++dev) {
 536                 struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 537                 struct osd_request *or;
 538
 539                 or = osd_start_request(_ios_od(ios, dev), GFP_KERNEL);
 540                 if (unlikely(!or)) {
 541                         ORE_ERR("%s: osd_start_request failed\n", __func__);
 542                         ret = -ENOMEM;
 543                         goto out;
 544                 }
 545                 per_dev->or = or;
 546                 per_dev->offset = master_dev->offset;
 547
 548                 if (ios->pages) {
 549                         struct bio *bio;
 550
 551                         if (per_dev != master_dev) {
 552                                 bio = bio_kmalloc(GFP_KERNEL,
 553                                                   master_dev->bio->bi_max_vecs);
 554                                 if (unlikely(!bio)) {
 555                                         ORE_DBGMSG(
 556                                               "Failed to allocate BIO size=%u\n",
 557                                               master_dev->bio->bi_max_vecs);
 558                                         ret = -ENOMEM;
 559                                         goto out;
 560                                 }
 561
 562                                 __bio_clone(bio, master_dev->bio);
 563                                 bio->bi_bdev = NULL;
 564                                 bio->bi_next = NULL;
 565                                 per_dev->length = master_dev->length;
 566                                 per_dev->bio =  bio;
 567                                 per_dev->dev = dev;
 568                         } else {
 569                                 bio = master_dev->bio;
 570                                 /* FIXME: bio_set_dir() */
 571                                 bio->bi_rw |= REQ_WRITE;
 572                         }
 573
 574                         osd_req_write(or, _ios_obj(ios, dev), per_dev->offset,
 575                                       bio, per_dev->length);
 576                         ORE_DBGMSG("write(0x%llx) offset=0x%llx "
 577                                       "length=0x%llx dev=%d\n",
 578                                      _LLU(_ios_obj(ios, dev)->id),
 579                                      _LLU(per_dev->offset),
 580                                      _LLU(per_dev->length), dev);
 581                 } else if (ios->kern_buff) {
 582                         ret = osd_req_write_kern(or, _ios_obj(ios, dev),
 583                                                  per_dev->offset,
 584                                                  ios->kern_buff, ios->length);
 585                         if (unlikely(ret))
 586                                 goto out;
 587                         ORE_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
 588                                       "length=0x%llx dev=%d\n",
 589                                      _LLU(_ios_obj(ios, dev)->id),
 590                                      _LLU(per_dev->offset),
 591                                      _LLU(ios->length), dev);
 592                 } else {
 593                         osd_req_set_attributes(or, _ios_obj(ios, dev));
 594                         ORE_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
 595                                      _LLU(_ios_obj(ios, dev)->id),
 596                                      ios->out_attr_len, dev);
 597                 }
 598
 599                 if (ios->out_attr)
 600                         osd_req_add_set_attr_list(or, ios->out_attr,
 601                                                   ios->out_attr_len);
 602
 603                 if (ios->in_attr)
 604                         osd_req_add_get_attr_list(or, ios->in_attr,
 605                                                   ios->in_attr_len);
 606         }
 607
 608 out:
 609         return ret;
 610 }
 611
 612 int ore_write(struct ore_io_state *ios)
 613 {
 614         int i;
 615         int ret;
 616
 617         ret = _prepare_for_striping(ios);
 618         if (unlikely(ret))
 619                 return ret;
 620
 621         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 622                 ret = _write_mirror(ios, i);
 623                 if (unlikely(ret))
 624                         return ret;
 625         }
 626
 627         ret = ore_io_execute(ios);
 628         return ret;
 629 }
 630 EXPORT_SYMBOL(ore_write);
 631
 632 static int _read_mirror(struct ore_io_state *ios, unsigned cur_comp)
 633 {
 634         struct osd_request *or;
 635         struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 636         struct osd_obj_id *obj = _ios_obj(ios, cur_comp);
 637         unsigned first_dev = (unsigned)obj->id;
 638
 639         if (ios->pages && !per_dev->length)
 640                 return 0; /* Just an empty slot */
 641
 642         first_dev = per_dev->dev + first_dev % ios->layout->mirrors_p1;
 643         or = osd_start_request(_ios_od(ios, first_dev), GFP_KERNEL);
 644         if (unlikely(!or)) {
 645                 ORE_ERR("%s: osd_start_request failed\n", __func__);
 646                 return -ENOMEM;
 647         }
 648         per_dev->or = or;
 649
 650         if (ios->pages) {
 651                 osd_req_read(or, obj, per_dev->offset,
 652                                 per_dev->bio, per_dev->length);
 653                 ORE_DBGMSG("read(0x%llx) offset=0x%llx length=0x%llx"
 654                              " dev=%d\n", _LLU(obj->id),
 655                              _LLU(per_dev->offset), _LLU(per_dev->length),
 656                              first_dev);
 657         } else if (ios->kern_buff) {
 658                 int ret = osd_req_read_kern(or, obj, per_dev->offset,
 659                                             ios->kern_buff, ios->length);
 660                 ORE_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
 661                               "length=0x%llx dev=%d ret=>%d\n",
 662                               _LLU(obj->id), _LLU(per_dev->offset),
 663                               _LLU(ios->length), first_dev, ret);
 664                 if (unlikely(ret))
 665                         return ret;
 666         } else {
 667                 osd_req_get_attributes(or, obj);
 668                 ORE_DBGMSG2("obj(0x%llx) get_attributes=%d dev=%d\n",
 669                               _LLU(obj->id),
 670                               ios->in_attr_len, first_dev);
 671         }
 672         if (ios->out_attr)
 673                 osd_req_add_set_attr_list(or, ios->out_attr, ios->out_attr_len);
 674
 675         if (ios->in_attr)
 676                 osd_req_add_get_attr_list(or, ios->in_attr, ios->in_attr_len);
 677
 678         return 0;
 679 }
 680
 681 int ore_read(struct ore_io_state *ios)
 682 {
 683         int i;
 684         int ret;
 685
 686         ret = _prepare_for_striping(ios);
 687         if (unlikely(ret))
 688                 return ret;
 689
 690         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 691                 ret = _read_mirror(ios, i);
 692                 if (unlikely(ret))
 693                         return ret;
 694         }
 695
 696         ret = ore_io_execute(ios);
 697         return ret;
 698 }
 699 EXPORT_SYMBOL(ore_read);
 700
 701 int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr)
 702 {
 703         struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
 704         void *iter = NULL;
 705         int nelem;
 706
 707         do {
 708                 nelem = 1;
 709                 osd_req_decode_get_attr_list(ios->per_dev[0].or,
 710                                              &cur_attr, &nelem, &iter);
 711                 if ((cur_attr.attr_page == attr->attr_page) &&
 712                     (cur_attr.attr_id == attr->attr_id)) {
 713                         attr->len = cur_attr.len;
 714                         attr->val_ptr = cur_attr.val_ptr;
 715                         return 0;
 716                 }
 717         } while (iter);
 718
 719         return -EIO;
 720 }
 721 EXPORT_SYMBOL(extract_attr_from_ios);
 722
 723 static int _truncate_mirrors(struct ore_io_state *ios, unsigned cur_comp,
 724                              struct osd_attr *attr)
 725 {
 726         int last_comp = cur_comp + ios->layout->mirrors_p1;
 727
 728         for (; cur_comp < last_comp; ++cur_comp) {
 729                 struct ore_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 730                 struct osd_request *or;
 731
 732                 or = osd_start_request(_ios_od(ios, cur_comp), GFP_KERNEL);
 733                 if (unlikely(!or)) {
 734                         ORE_ERR("%s: osd_start_request failed\n", __func__);
 735                         return -ENOMEM;
 736                 }
 737                 per_dev->or = or;
 738
 739                 osd_req_set_attributes(or, _ios_obj(ios, cur_comp));
 740                 osd_req_add_set_attr_list(or, attr, 1);
 741         }
 742
 743         return 0;
 744 }
 745
 746 struct _trunc_info {
 747         struct _striping_info si;
 748         u64 prev_group_obj_off;
 749         u64 next_group_obj_off;
 750
 751         unsigned first_group_dev;
 752         unsigned nex_group_dev;
 753         unsigned max_devs;
 754 };
 755
 756 void _calc_trunk_info(struct ore_layout *layout, u64 file_offset,
 757                        struct _trunc_info *ti)
 758 {
 759         unsigned stripe_unit = layout->stripe_unit;
 760
 761         _calc_stripe_info(layout, file_offset, &ti->si);
 762
 763         ti->prev_group_obj_off = ti->si.M * stripe_unit;
 764         ti->next_group_obj_off = ti->si.M ? (ti->si.M - 1) * stripe_unit : 0;
 765
 766         ti->first_group_dev = ti->si.dev - (ti->si.dev % layout->group_width);
 767         ti->nex_group_dev = ti->first_group_dev + layout->group_width;
 768         ti->max_devs = layout->group_width * layout->group_count;
 769 }
 770
 771 int ore_truncate(struct ore_layout *layout, struct ore_components *comps,
 772                    u64 size)
 773 {
 774         struct ore_io_state *ios;
 775         struct exofs_trunc_attr {
 776                 struct osd_attr attr;
 777                 __be64 newsize;
 778         } *size_attrs;
 779         struct _trunc_info ti;
 780         int i, ret;
 781
 782         ret = ore_get_io_state(layout, comps, &ios);
 783         if (unlikely(ret))
 784                 return ret;
 785
 786         _calc_trunk_info(ios->layout, size, &ti);
 787
 788         size_attrs = kcalloc(ti.max_devs, sizeof(*size_attrs),
 789                              GFP_KERNEL);
 790         if (unlikely(!size_attrs)) {
 791                 ret = -ENOMEM;
 792                 goto out;
 793         }
 794
 795         ios->numdevs = ios->comps->numdevs;
 796
 797         for (i = 0; i < ti.max_devs; ++i) {
 798                 struct exofs_trunc_attr *size_attr = &size_attrs[i];
 799                 u64 obj_size;
 800
 801                 if (i < ti.first_group_dev)
 802                         obj_size = ti.prev_group_obj_off;
 803                 else if (i >= ti.nex_group_dev)
 804                         obj_size = ti.next_group_obj_off;
 805                 else if (i < ti.si.dev) /* dev within this group */
 806                         obj_size = ti.si.obj_offset +
 807                                       ios->layout->stripe_unit - ti.si.unit_off;
 808                 else if (i == ti.si.dev)
 809                         obj_size = ti.si.obj_offset;
 810                 else /* i > ti.dev */
 811                         obj_size = ti.si.obj_offset - ti.si.unit_off;
 812
 813                 size_attr->newsize = cpu_to_be64(obj_size);
 814                 size_attr->attr = g_attr_logical_length;
 815                 size_attr->attr.val_ptr = &size_attr->newsize;
 816
 817                 ORE_DBGMSG("trunc(0x%llx) obj_offset=0x%llx dev=%d\n",
 818                              _LLU(comps->comps->obj.id), _LLU(obj_size), i);
 819                 ret = _truncate_mirrors(ios, i * ios->layout->mirrors_p1,
 820                                         &size_attr->attr);
 821                 if (unlikely(ret))
 822                         goto out;
 823         }
 824         ret = ore_io_execute(ios);
 825
 826 out:
 827         kfree(size_attrs);
 828         ore_put_io_state(ios);
 829         return ret;
 830 }
 831 EXPORT_SYMBOL(ore_truncate);
 832
 833 const struct osd_attr g_attr_logical_length = ATTR_DEF(
 834         OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
 835 EXPORT_SYMBOL(g_attr_logical_length);