fs/exofs/ios.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 <scsi/scsi_device.h>
  26 #include <asm/div64.h>
  27
  28 #include "exofs.h"
  29
  30 #define EXOFS_DBGMSG2(M...) do {} while (0)
  31 /* #define EXOFS_DBGMSG2 EXOFS_DBGMSG */
  32
  33 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
  34 {
  35         osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
  36 }
  37
  38 int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
  39                     u64 offset, void *p, unsigned length)
  40 {
  41         struct osd_request *or = osd_start_request(od, GFP_KERNEL);
  42 /*      struct osd_sense_info osi = {.key = 0};*/
  43         int ret;
  44
  45         if (unlikely(!or)) {
  46                 EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
  47                 return -ENOMEM;
  48         }
  49         ret = osd_req_read_kern(or, obj, offset, p, length);
  50         if (unlikely(ret)) {
  51                 EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
  52                 goto out;
  53         }
  54
  55         ret = osd_finalize_request(or, 0, cred, NULL);
  56         if (unlikely(ret)) {
  57                 EXOFS_DBGMSG("Faild to osd_finalize_request() => %d\n", ret);
  58                 goto out;
  59         }
  60
  61         ret = osd_execute_request(or);
  62         if (unlikely(ret))
  63                 EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
  64         /* osd_req_decode_sense(or, ret); */
  65
  66 out:
  67         osd_end_request(or);
  68         return ret;
  69 }
  70
  71 int exofs_get_io_state(struct exofs_layout *layout,
  72                        struct exofs_io_state **pios)
  73 {
  74         struct exofs_io_state *ios;
  75
  76         /*TODO: Maybe use kmem_cach per sbi of size
  77          * exofs_io_state_size(layout->s_numdevs)
  78          */
  79         ios = kzalloc(exofs_io_state_size(layout->s_numdevs), GFP_KERNEL);
  80         if (unlikely(!ios)) {
  81                 EXOFS_DBGMSG("Faild kzalloc bytes=%d\n",
  82                              exofs_io_state_size(layout->s_numdevs));
  83                 *pios = NULL;
  84                 return -ENOMEM;
  85         }
  86
  87         ios->layout = layout;
  88         ios->obj.partition = layout->s_pid;
  89         *pios = ios;
  90         return 0;
  91 }
  92
  93 void exofs_put_io_state(struct exofs_io_state *ios)
  94 {
  95         if (ios) {
  96                 unsigned i;
  97
  98                 for (i = 0; i < ios->numdevs; i++) {
  99                         struct exofs_per_dev_state *per_dev = &ios->per_dev[i];
 100
 101                         if (per_dev->or)
 102                                 osd_end_request(per_dev->or);
 103                         if (per_dev->bio)
 104                                 bio_put(per_dev->bio);
 105                 }
 106
 107                 kfree(ios);
 108         }
 109 }
 110
 111 unsigned exofs_layout_od_id(struct exofs_layout *layout,
 112                             osd_id obj_no, unsigned layout_index)
 113 {
 114 /*      switch (layout->lay_func) {
 115         case LAYOUT_MOVING_WINDOW:
 116         {*/
 117                 unsigned dev_mod = obj_no;
 118
 119                 return (layout_index + dev_mod * layout->mirrors_p1) %
 120                                                               layout->s_numdevs;
 121 /*      }
 122         case LAYOUT_FUNC_IMPLICT:
 123                 return layout->devs[layout_index];
 124         }*/
 125 }
 126
 127 static inline struct osd_dev *exofs_ios_od(struct exofs_io_state *ios,
 128                                            unsigned layout_index)
 129 {
 130         return ios->layout->s_ods[
 131                 exofs_layout_od_id(ios->layout, ios->obj.id, layout_index)];
 132 }
 133
 134 static void _sync_done(struct exofs_io_state *ios, void *p)
 135 {
 136         struct completion *waiting = p;
 137
 138         complete(waiting);
 139 }
 140
 141 static void _last_io(struct kref *kref)
 142 {
 143         struct exofs_io_state *ios = container_of(
 144                                         kref, struct exofs_io_state, kref);
 145
 146         ios->done(ios, ios->private);
 147 }
 148
 149 static void _done_io(struct osd_request *or, void *p)
 150 {
 151         struct exofs_io_state *ios = p;
 152
 153         kref_put(&ios->kref, _last_io);
 154 }
 155
 156 static int exofs_io_execute(struct exofs_io_state *ios)
 157 {
 158         DECLARE_COMPLETION_ONSTACK(wait);
 159         bool sync = (ios->done == NULL);
 160         int i, ret;
 161
 162         if (sync) {
 163                 ios->done = _sync_done;
 164                 ios->private = &wait;
 165         }
 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                 ret = osd_finalize_request(or, 0, ios->cred, NULL);
 173                 if (unlikely(ret)) {
 174                         EXOFS_DBGMSG("Faild to osd_finalize_request() => %d\n",
 175                                      ret);
 176                         return ret;
 177                 }
 178         }
 179
 180         kref_init(&ios->kref);
 181
 182         for (i = 0; i < ios->numdevs; i++) {
 183                 struct osd_request *or = ios->per_dev[i].or;
 184                 if (unlikely(!or))
 185                         continue;
 186
 187                 kref_get(&ios->kref);
 188                 osd_execute_request_async(or, _done_io, ios);
 189         }
 190
 191         kref_put(&ios->kref, _last_io);
 192         ret = 0;
 193
 194         if (sync) {
 195                 wait_for_completion(&wait);
 196                 ret = exofs_check_io(ios, NULL);
 197         }
 198         return ret;
 199 }
 200
 201 static void _clear_bio(struct bio *bio)
 202 {
 203         struct bio_vec *bv;
 204         unsigned i;
 205
 206         __bio_for_each_segment(bv, bio, i, 0) {
 207                 unsigned this_count = bv->bv_len;
 208
 209                 if (likely(PAGE_SIZE == this_count))
 210                         clear_highpage(bv->bv_page);
 211                 else
 212                         zero_user(bv->bv_page, bv->bv_offset, this_count);
 213         }
 214 }
 215
 216 int exofs_check_io(struct exofs_io_state *ios, u64 *resid)
 217 {
 218         enum osd_err_priority acumulated_osd_err = 0;
 219         int acumulated_lin_err = 0;
 220         int i;
 221
 222         for (i = 0; i < ios->numdevs; i++) {
 223                 struct osd_sense_info osi;
 224                 struct osd_request *or = ios->per_dev[i].or;
 225                 int ret;
 226
 227                 if (unlikely(!or))
 228                         continue;
 229
 230                 ret = osd_req_decode_sense(or, &osi);
 231                 if (likely(!ret))
 232                         continue;
 233
 234                 if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) {
 235                         /* start read offset passed endof file */
 236                         _clear_bio(ios->per_dev[i].bio);
 237                         EXOFS_DBGMSG("start read offset passed end of file "
 238                                 "offset=0x%llx, length=0x%llx\n",
 239                                 _LLU(ios->per_dev[i].offset),
 240                                 _LLU(ios->per_dev[i].length));
 241
 242                         continue; /* we recovered */
 243                 }
 244
 245                 if (osi.osd_err_pri >= acumulated_osd_err) {
 246                         acumulated_osd_err = osi.osd_err_pri;
 247                         acumulated_lin_err = ret;
 248                 }
 249         }
 250
 251         /* TODO: raid specific residual calculations */
 252         if (resid) {
 253                 if (likely(!acumulated_lin_err))
 254                         *resid = 0;
 255                 else
 256                         *resid = ios->length;
 257         }
 258
 259         return acumulated_lin_err;
 260 }
 261
 262 /*
 263  * L - logical offset into the file
 264  *
 265  * U - The number of bytes in a stripe within a group
 266  *
 267  *      U = stripe_unit * group_width
 268  *
 269  * T - The number of bytes striped within a group of component objects
 270  *     (before advancing to the next group)
 271  *
 272  *      T = stripe_unit * group_width * group_depth
 273  *
 274  * S - The number of bytes striped across all component objects
 275  *     before the pattern repeats
 276  *
 277  *      S = stripe_unit * group_width * group_depth * group_count
 278  *
 279  * M - The "major" (i.e., across all components) stripe number
 280  *
 281  *      M = L / S
 282  *
 283  * G - Counts the groups from the beginning of the major stripe
 284  *
 285  *      G = (L - (M * S)) / T   [or (L % S) / T]
 286  *
 287  * H - The byte offset within the group
 288  *
 289  *      H = (L - (M * S)) % T   [or (L % S) % T]
 290  *
 291  * N - The "minor" (i.e., across the group) stripe number
 292  *
 293  *      N = H / U
 294  *
 295  * C - The component index coresponding to L
 296  *
 297  *      C = (H - (N * U)) / stripe_unit + G * group_width
 298  *      [or (L % U) / stripe_unit + G * group_width]
 299  *
 300  * O - The component offset coresponding to L
 301  *
 302  *      O = L % stripe_unit + N * stripe_unit + M * group_depth * stripe_unit
 303  */
 304 struct _striping_info {
 305         u64 obj_offset;
 306         u64 group_length;
 307         u64 total_group_length;
 308         u64 Major;
 309         unsigned dev;
 310         unsigned unit_off;
 311 };
 312
 313 static void _calc_stripe_info(struct exofs_io_state *ios, u64 file_offset,
 314                               struct _striping_info *si)
 315 {
 316         u32     stripe_unit = ios->layout->stripe_unit;
 317         u32     group_width = ios->layout->group_width;
 318         u64     group_depth = ios->layout->group_depth;
 319
 320         u32     U = stripe_unit * group_width;
 321         u64     T = U * group_depth;
 322         u64     S = T * ios->layout->group_count;
 323         u64     M = div64_u64(file_offset, S);
 324
 325         /*
 326         G = (L - (M * S)) / T
 327         H = (L - (M * S)) % T
 328         */
 329         u64     LmodS = file_offset - M * S;
 330         u32     G = div64_u64(LmodS, T);
 331         u64     H = LmodS - G * T;
 332
 333         u32     N = div_u64(H, U);
 334
 335         /* "H - (N * U)" is just "H % U" so it's bound to u32 */
 336         si->dev = (u32)(H - (N * U)) / stripe_unit + G * group_width;
 337         si->dev *= ios->layout->mirrors_p1;
 338
 339         div_u64_rem(file_offset, stripe_unit, &si->unit_off);
 340
 341         si->obj_offset = si->unit_off + (N * stripe_unit) +
 342                                   (M * group_depth * stripe_unit);
 343
 344         si->group_length = T - H;
 345         si->total_group_length = T;
 346         si->Major = M;
 347 }
 348
 349 static int _add_stripe_unit(struct exofs_io_state *ios,  unsigned *cur_pg,
 350                 unsigned pgbase, struct exofs_per_dev_state *per_dev,
 351                 int cur_len)
 352 {
 353         unsigned pg = *cur_pg;
 354         struct request_queue *q =
 355                         osd_request_queue(exofs_ios_od(ios, per_dev->dev));
 356
 357         per_dev->length += cur_len;
 358
 359         if (per_dev->bio == NULL) {
 360                 unsigned pages_in_stripe = ios->layout->group_width *
 361                                         (ios->layout->stripe_unit / PAGE_SIZE);
 362                 unsigned bio_size = (ios->nr_pages + pages_in_stripe) /
 363                                                 ios->layout->group_width;
 364
 365                 per_dev->bio = bio_kmalloc(GFP_KERNEL, bio_size);
 366                 if (unlikely(!per_dev->bio)) {
 367                         EXOFS_DBGMSG("Faild to allocate BIO size=%u\n",
 368                                      bio_size);
 369                         return -ENOMEM;
 370                 }
 371         }
 372
 373         while (cur_len > 0) {
 374                 unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
 375                 unsigned added_len;
 376
 377                 BUG_ON(ios->nr_pages <= pg);
 378                 cur_len -= pglen;
 379
 380                 added_len = bio_add_pc_page(q, per_dev->bio, ios->pages[pg],
 381                                             pglen, pgbase);
 382                 if (unlikely(pglen != added_len))
 383                         return -ENOMEM;
 384                 pgbase = 0;
 385                 ++pg;
 386         }
 387         BUG_ON(cur_len);
 388
 389         *cur_pg = pg;
 390         return 0;
 391 }
 392
 393 static int _prepare_one_group(struct exofs_io_state *ios, u64 length,
 394                               struct _striping_info *si, unsigned first_comp)
 395 {
 396         unsigned stripe_unit = ios->layout->stripe_unit;
 397         unsigned mirrors_p1 = ios->layout->mirrors_p1;
 398         unsigned devs_in_group = ios->layout->group_width * mirrors_p1;
 399         unsigned dev = si->dev;
 400         unsigned first_dev = dev - (dev % devs_in_group);
 401         unsigned comp = first_comp + (dev - first_dev);
 402         unsigned max_comp = ios->numdevs ? ios->numdevs - mirrors_p1 : 0;
 403         unsigned cur_pg = ios->pages_consumed;
 404         int ret = 0;
 405
 406         while (length) {
 407                 struct exofs_per_dev_state *per_dev = &ios->per_dev[comp];
 408                 unsigned cur_len, page_off = 0;
 409
 410                 if (!per_dev->length) {
 411                         per_dev->dev = dev;
 412                         if (dev < si->dev) {
 413                                 per_dev->offset = si->obj_offset + stripe_unit -
 414                                                                    si->unit_off;
 415                                 cur_len = stripe_unit;
 416                         } else if (dev == si->dev) {
 417                                 per_dev->offset = si->obj_offset;
 418                                 cur_len = stripe_unit - si->unit_off;
 419                                 page_off = si->unit_off & ~PAGE_MASK;
 420                                 BUG_ON(page_off && (page_off != ios->pgbase));
 421                         } else { /* dev > si->dev */
 422                                 per_dev->offset = si->obj_offset - si->unit_off;
 423                                 cur_len = stripe_unit;
 424                         }
 425
 426                         if (max_comp < comp)
 427                                 max_comp = comp;
 428
 429                         dev += mirrors_p1;
 430                         dev = (dev % devs_in_group) + first_dev;
 431                 } else {
 432                         cur_len = stripe_unit;
 433                 }
 434                 if (cur_len >= length)
 435                         cur_len = length;
 436
 437                 ret = _add_stripe_unit(ios, &cur_pg, page_off , per_dev,
 438                                        cur_len);
 439                 if (unlikely(ret))
 440                         goto out;
 441
 442                 comp += mirrors_p1;
 443                 comp = (comp % devs_in_group) + first_comp;
 444
 445                 length -= cur_len;
 446         }
 447 out:
 448         ios->numdevs = max_comp + mirrors_p1;
 449         ios->pages_consumed = cur_pg;
 450         return ret;
 451 }
 452
 453 static int _prepare_for_striping(struct exofs_io_state *ios)
 454 {
 455         u64 length = ios->length;
 456         struct _striping_info si;
 457         unsigned devs_in_group = ios->layout->group_width *
 458                                  ios->layout->mirrors_p1;
 459         unsigned first_comp = 0;
 460         int ret = 0;
 461
 462         _calc_stripe_info(ios, ios->offset, &si);
 463
 464         if (!ios->pages) {
 465                 if (ios->kern_buff) {
 466                         struct exofs_per_dev_state *per_dev = &ios->per_dev[0];
 467
 468                         per_dev->offset = si.obj_offset;
 469                         per_dev->dev = si.dev;
 470
 471                         /* no cross device without page array */
 472                         BUG_ON((ios->layout->group_width > 1) &&
 473                                (si.unit_off + ios->length >
 474                                 ios->layout->stripe_unit));
 475                 }
 476                 ios->numdevs = ios->layout->mirrors_p1;
 477                 return 0;
 478         }
 479
 480         while (length) {
 481                 if (length < si.group_length)
 482                         si.group_length = length;
 483
 484                 ret = _prepare_one_group(ios, si.group_length, &si, first_comp);
 485                 if (unlikely(ret))
 486                         goto out;
 487
 488                 length -= si.group_length;
 489
 490                 si.group_length = si.total_group_length;
 491                 si.unit_off = 0;
 492                 ++si.Major;
 493                 si.obj_offset = si.Major * ios->layout->stripe_unit *
 494                                                 ios->layout->group_depth;
 495
 496                 si.dev = (si.dev - (si.dev % devs_in_group)) + devs_in_group;
 497                 si.dev %= ios->layout->s_numdevs;
 498
 499                 first_comp += devs_in_group;
 500                 first_comp %= ios->layout->s_numdevs;
 501         }
 502
 503 out:
 504         return ret;
 505 }
 506
 507 int exofs_sbi_create(struct exofs_io_state *ios)
 508 {
 509         int i, ret;
 510
 511         for (i = 0; i < ios->layout->s_numdevs; i++) {
 512                 struct osd_request *or;
 513
 514                 or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
 515                 if (unlikely(!or)) {
 516                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 517                         ret = -ENOMEM;
 518                         goto out;
 519                 }
 520                 ios->per_dev[i].or = or;
 521                 ios->numdevs++;
 522
 523                 osd_req_create_object(or, &ios->obj);
 524         }
 525         ret = exofs_io_execute(ios);
 526
 527 out:
 528         return ret;
 529 }
 530
 531 int exofs_sbi_remove(struct exofs_io_state *ios)
 532 {
 533         int i, ret;
 534
 535         for (i = 0; i < ios->layout->s_numdevs; i++) {
 536                 struct osd_request *or;
 537
 538                 or = osd_start_request(exofs_ios_od(ios, i), GFP_KERNEL);
 539                 if (unlikely(!or)) {
 540                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 541                         ret = -ENOMEM;
 542                         goto out;
 543                 }
 544                 ios->per_dev[i].or = or;
 545                 ios->numdevs++;
 546
 547                 osd_req_remove_object(or, &ios->obj);
 548         }
 549         ret = exofs_io_execute(ios);
 550
 551 out:
 552         return ret;
 553 }
 554
 555 static int _sbi_write_mirror(struct exofs_io_state *ios, int cur_comp)
 556 {
 557         struct exofs_per_dev_state *master_dev = &ios->per_dev[cur_comp];
 558         unsigned dev = ios->per_dev[cur_comp].dev;
 559         unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
 560         int ret = 0;
 561
 562         if (ios->pages && !master_dev->length)
 563                 return 0; /* Just an empty slot */
 564
 565         for (; cur_comp < last_comp; ++cur_comp, ++dev) {
 566                 struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 567                 struct osd_request *or;
 568
 569                 or = osd_start_request(exofs_ios_od(ios, dev), GFP_KERNEL);
 570                 if (unlikely(!or)) {
 571                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 572                         ret = -ENOMEM;
 573                         goto out;
 574                 }
 575                 per_dev->or = or;
 576                 per_dev->offset = master_dev->offset;
 577
 578                 if (ios->pages) {
 579                         struct bio *bio;
 580
 581                         if (per_dev != master_dev) {
 582                                 bio = bio_kmalloc(GFP_KERNEL,
 583                                                   master_dev->bio->bi_max_vecs);
 584                                 if (unlikely(!bio)) {
 585                                         EXOFS_DBGMSG(
 586                                               "Faild to allocate BIO size=%u\n",
 587                                               master_dev->bio->bi_max_vecs);
 588                                         ret = -ENOMEM;
 589                                         goto out;
 590                                 }
 591
 592                                 __bio_clone(bio, master_dev->bio);
 593                                 bio->bi_bdev = NULL;
 594                                 bio->bi_next = NULL;
 595                                 per_dev->length = master_dev->length;
 596                                 per_dev->bio =  bio;
 597                                 per_dev->dev = dev;
 598                         } else {
 599                                 bio = master_dev->bio;
 600                                 /* FIXME: bio_set_dir() */
 601                                 bio->bi_rw |= (1 << BIO_RW);
 602                         }
 603
 604                         osd_req_write(or, &ios->obj, per_dev->offset, bio,
 605                                       per_dev->length);
 606                         EXOFS_DBGMSG("write(0x%llx) offset=0x%llx "
 607                                       "length=0x%llx dev=%d\n",
 608                                      _LLU(ios->obj.id), _LLU(per_dev->offset),
 609                                      _LLU(per_dev->length), dev);
 610                 } else if (ios->kern_buff) {
 611                         ret = osd_req_write_kern(or, &ios->obj, per_dev->offset,
 612                                            ios->kern_buff, ios->length);
 613                         if (unlikely(ret))
 614                                 goto out;
 615                         EXOFS_DBGMSG2("write_kern(0x%llx) offset=0x%llx "
 616                                       "length=0x%llx dev=%d\n",
 617                                      _LLU(ios->obj.id), _LLU(per_dev->offset),
 618                                      _LLU(ios->length), dev);
 619                 } else {
 620                         osd_req_set_attributes(or, &ios->obj);
 621                         EXOFS_DBGMSG2("obj(0x%llx) set_attributes=%d dev=%d\n",
 622                                      _LLU(ios->obj.id), ios->out_attr_len, dev);
 623                 }
 624
 625                 if (ios->out_attr)
 626                         osd_req_add_set_attr_list(or, ios->out_attr,
 627                                                   ios->out_attr_len);
 628
 629                 if (ios->in_attr)
 630                         osd_req_add_get_attr_list(or, ios->in_attr,
 631                                                   ios->in_attr_len);
 632         }
 633
 634 out:
 635         return ret;
 636 }
 637
 638 int exofs_sbi_write(struct exofs_io_state *ios)
 639 {
 640         int i;
 641         int ret;
 642
 643         ret = _prepare_for_striping(ios);
 644         if (unlikely(ret))
 645                 return ret;
 646
 647         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 648                 ret = _sbi_write_mirror(ios, i);
 649                 if (unlikely(ret))
 650                         return ret;
 651         }
 652
 653         ret = exofs_io_execute(ios);
 654         return ret;
 655 }
 656
 657 static int _sbi_read_mirror(struct exofs_io_state *ios, unsigned cur_comp)
 658 {
 659         struct osd_request *or;
 660         struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 661         unsigned first_dev = (unsigned)ios->obj.id;
 662
 663         if (ios->pages && !per_dev->length)
 664                 return 0; /* Just an empty slot */
 665
 666         first_dev = per_dev->dev + first_dev % ios->layout->mirrors_p1;
 667         or = osd_start_request(exofs_ios_od(ios, first_dev), GFP_KERNEL);
 668         if (unlikely(!or)) {
 669                 EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 670                 return -ENOMEM;
 671         }
 672         per_dev->or = or;
 673
 674         if (ios->pages) {
 675                 osd_req_read(or, &ios->obj, per_dev->offset,
 676                                 per_dev->bio, per_dev->length);
 677                 EXOFS_DBGMSG("read(0x%llx) offset=0x%llx length=0x%llx"
 678                              " dev=%d\n", _LLU(ios->obj.id),
 679                              _LLU(per_dev->offset), _LLU(per_dev->length),
 680                              first_dev);
 681         } else if (ios->kern_buff) {
 682                 int ret = osd_req_read_kern(or, &ios->obj, per_dev->offset,
 683                                             ios->kern_buff, ios->length);
 684                 EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
 685                               "length=0x%llx dev=%d ret=>%d\n",
 686                               _LLU(ios->obj.id), _LLU(per_dev->offset),
 687                               _LLU(ios->length), first_dev, ret);
 688                 if (unlikely(ret))
 689                         return ret;
 690         } else {
 691                 osd_req_get_attributes(or, &ios->obj);
 692                 EXOFS_DBGMSG2("obj(0x%llx) get_attributes=%d dev=%d\n",
 693                               _LLU(ios->obj.id), ios->in_attr_len, first_dev);
 694         }
 695         if (ios->out_attr)
 696                 osd_req_add_set_attr_list(or, ios->out_attr, ios->out_attr_len);
 697
 698         if (ios->in_attr)
 699                 osd_req_add_get_attr_list(or, ios->in_attr, ios->in_attr_len);
 700
 701         return 0;
 702 }
 703
 704 int exofs_sbi_read(struct exofs_io_state *ios)
 705 {
 706         int i;
 707         int ret;
 708
 709         ret = _prepare_for_striping(ios);
 710         if (unlikely(ret))
 711                 return ret;
 712
 713         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 714                 ret = _sbi_read_mirror(ios, i);
 715                 if (unlikely(ret))
 716                         return ret;
 717         }
 718
 719         ret = exofs_io_execute(ios);
 720         return ret;
 721 }
 722
 723 int extract_attr_from_ios(struct exofs_io_state *ios, struct osd_attr *attr)
 724 {
 725         struct osd_attr cur_attr = {.attr_page = 0}; /* start with zeros */
 726         void *iter = NULL;
 727         int nelem;
 728
 729         do {
 730                 nelem = 1;
 731                 osd_req_decode_get_attr_list(ios->per_dev[0].or,
 732                                              &cur_attr, &nelem, &iter);
 733                 if ((cur_attr.attr_page == attr->attr_page) &&
 734                     (cur_attr.attr_id == attr->attr_id)) {
 735                         attr->len = cur_attr.len;
 736                         attr->val_ptr = cur_attr.val_ptr;
 737                         return 0;
 738                 }
 739         } while (iter);
 740
 741         return -EIO;
 742 }
 743
 744 static int _truncate_mirrors(struct exofs_io_state *ios, unsigned cur_comp,
 745                              struct osd_attr *attr)
 746 {
 747         int last_comp = cur_comp + ios->layout->mirrors_p1;
 748
 749         for (; cur_comp < last_comp; ++cur_comp) {
 750                 struct exofs_per_dev_state *per_dev = &ios->per_dev[cur_comp];
 751                 struct osd_request *or;
 752
 753                 or = osd_start_request(exofs_ios_od(ios, cur_comp), GFP_KERNEL);
 754                 if (unlikely(!or)) {
 755                         EXOFS_ERR("%s: osd_start_request failed\n", __func__);
 756                         return -ENOMEM;
 757                 }
 758                 per_dev->or = or;
 759
 760                 osd_req_set_attributes(or, &ios->obj);
 761                 osd_req_add_set_attr_list(or, attr, 1);
 762         }
 763
 764         return 0;
 765 }
 766
 767 int exofs_oi_truncate(struct exofs_i_info *oi, u64 size)
 768 {
 769         struct exofs_sb_info *sbi = oi->vfs_inode.i_sb->s_fs_info;
 770         struct exofs_io_state *ios;
 771         struct exofs_trunc_attr {
 772                 struct osd_attr attr;
 773                 __be64 newsize;
 774         } *size_attrs;
 775         struct _striping_info si;
 776         int i, ret;
 777
 778         ret = exofs_get_io_state(&sbi->layout, &ios);
 779         if (unlikely(ret))
 780                 return ret;
 781
 782         size_attrs = kcalloc(ios->layout->group_width, sizeof(*size_attrs),
 783                              GFP_KERNEL);
 784         if (unlikely(!size_attrs)) {
 785                 ret = -ENOMEM;
 786                 goto out;
 787         }
 788
 789         ios->obj.id = exofs_oi_objno(oi);
 790         ios->cred = oi->i_cred;
 791
 792         ios->numdevs = ios->layout->s_numdevs;
 793         _calc_stripe_info(ios, size, &si);
 794
 795         for (i = 0; i < ios->layout->group_width; ++i) {
 796                 struct exofs_trunc_attr *size_attr = &size_attrs[i];
 797                 u64 obj_size;
 798
 799                 if (i < si.dev)
 800                         obj_size = si.obj_offset +
 801                                         ios->layout->stripe_unit - si.unit_off;
 802                 else if (i == si.dev)
 803                         obj_size = si.obj_offset;
 804                 else /* i > si.dev */
 805                         obj_size = si.obj_offset - si.unit_off;
 806
 807                 size_attr->newsize = cpu_to_be64(obj_size);
 808                 size_attr->attr = g_attr_logical_length;
 809                 size_attr->attr.val_ptr = &size_attr->newsize;
 810
 811                 ret = _truncate_mirrors(ios, i * ios->layout->mirrors_p1,
 812                                         &size_attr->attr);
 813                 if (unlikely(ret))
 814                         goto out;
 815         }
 816         ret = exofs_io_execute(ios);
 817
 818 out:
 819         kfree(size_attrs);
 820         exofs_put_io_state(ios);
 821         return ret;
 822 }