fs/nfs/objlayout/objio_osd.c

   1 /*
   2  *  pNFS Objects layout implementation over open-osd initiator library
   3  *
   4  *  Copyright (C) 2009 Panasas Inc. [year of first publication]
   5  *  All rights reserved.
   6  *
   7  *  Benny Halevy <bhalevy@panasas.com>
   8  *  Boaz Harrosh <bharrosh@panasas.com>
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License version 2
  12  *  See the file COPYING included with this distribution for more details.
  13  *
  14  *  Redistribution and use in source and binary forms, with or without
  15  *  modification, are permitted provided that the following conditions
  16  *  are met:
  17  *
  18  *  1. Redistributions of source code must retain the above copyright
  19  *     notice, this list of conditions and the following disclaimer.
  20  *  2. Redistributions in binary form must reproduce the above copyright
  21  *     notice, this list of conditions and the following disclaimer in the
  22  *     documentation and/or other materials provided with the distribution.
  23  *  3. Neither the name of the Panasas company nor the names of its
  24  *     contributors may be used to endorse or promote products derived
  25  *     from this software without specific prior written permission.
  26  *
  27  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  28  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  29  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  30  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  32  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  33  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  34  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  35  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  36  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  37  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  38  */
  39
  40 #include <linux/module.h>
  41 #include <scsi/osd_initiator.h>
  42
  43 #include "objlayout.h"
  44
  45 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  46
  47 #define _LLU(x) ((unsigned long long)x)
  48
  49 enum { BIO_MAX_PAGES_KMALLOC =
  50                 (PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec),
  51 };
  52
  53 struct objio_dev_ent {
  54         struct nfs4_deviceid_node id_node;
  55         struct osd_dev *od;
  56 };
  57
  58 static void
  59 objio_free_deviceid_node(struct nfs4_deviceid_node *d)
  60 {
  61         struct objio_dev_ent *de = container_of(d, struct objio_dev_ent, id_node);
  62
  63         dprintk("%s: free od=%p\n", __func__, de->od);
  64         osduld_put_device(de->od);
  65         kfree(de);
  66 }
  67
  68 static struct objio_dev_ent *_dev_list_find(const struct nfs_server *nfss,
  69         const struct nfs4_deviceid *d_id)
  70 {
  71         struct nfs4_deviceid_node *d;
  72         struct objio_dev_ent *de;
  73
  74         d = nfs4_find_get_deviceid(nfss->pnfs_curr_ld, nfss->nfs_client, d_id);
  75         if (!d)
  76                 return NULL;
  77
  78         de = container_of(d, struct objio_dev_ent, id_node);
  79         return de;
  80 }
  81
  82 static struct objio_dev_ent *
  83 _dev_list_add(const struct nfs_server *nfss,
  84         const struct nfs4_deviceid *d_id, struct osd_dev *od,
  85         gfp_t gfp_flags)
  86 {
  87         struct nfs4_deviceid_node *d;
  88         struct objio_dev_ent *de = kzalloc(sizeof(*de), gfp_flags);
  89         struct objio_dev_ent *n;
  90
  91         if (!de) {
  92                 dprintk("%s: -ENOMEM od=%p\n", __func__, od);
  93                 return NULL;
  94         }
  95
  96         dprintk("%s: Adding od=%p\n", __func__, od);
  97         nfs4_init_deviceid_node(&de->id_node,
  98                                 nfss->pnfs_curr_ld,
  99                                 nfss->nfs_client,
 100                                 d_id);
 101         de->od = od;
 102
 103         d = nfs4_insert_deviceid_node(&de->id_node);
 104         n = container_of(d, struct objio_dev_ent, id_node);
 105         if (n != de) {
 106                 dprintk("%s: Race with other n->od=%p\n", __func__, n->od);
 107                 objio_free_deviceid_node(&de->id_node);
 108                 de = n;
 109         }
 110
 111         atomic_inc(&de->id_node.ref);
 112         return de;
 113 }
 114
 115 struct caps_buffers {
 116         u8 caps_key[OSD_CRYPTO_KEYID_SIZE];
 117         u8 creds[OSD_CAP_LEN];
 118 };
 119
 120 struct objio_segment {
 121         struct pnfs_layout_segment lseg;
 122
 123         struct pnfs_osd_object_cred *comps;
 124
 125         unsigned mirrors_p1;
 126         unsigned stripe_unit;
 127         unsigned group_width;   /* Data stripe_units without integrity comps */
 128         u64 group_depth;
 129         unsigned group_count;
 130
 131         unsigned comps_index;
 132         unsigned num_comps;
 133         /* variable length */
 134         struct objio_dev_ent *ods[];
 135 };
 136
 137 static inline struct objio_segment *
 138 OBJIO_LSEG(struct pnfs_layout_segment *lseg)
 139 {
 140         return container_of(lseg, struct objio_segment, lseg);
 141 }
 142
 143 struct objio_state;
 144 typedef ssize_t (*objio_done_fn)(struct objio_state *ios);
 145
 146 struct objio_state {
 147         /* Generic layer */
 148         struct objlayout_io_state ol_state;
 149
 150         struct objio_segment *layout;
 151
 152         struct kref kref;
 153         objio_done_fn done;
 154         void *private;
 155
 156         unsigned long length;
 157         unsigned numdevs; /* Actually used devs in this IO */
 158         /* A per-device variable array of size numdevs */
 159         struct _objio_per_comp {
 160                 struct bio *bio;
 161                 struct osd_request *or;
 162                 unsigned long length;
 163                 u64 offset;
 164                 unsigned dev;
 165         } per_dev[];
 166 };
 167
 168 /* Send and wait for a get_device_info of devices in the layout,
 169    then look them up with the osd_initiator library */
 170 static struct objio_dev_ent *_device_lookup(struct pnfs_layout_hdr *pnfslay,
 171                                 struct objio_segment *objio_seg, unsigned comp,
 172                                 gfp_t gfp_flags)
 173 {
 174         struct pnfs_osd_deviceaddr *deviceaddr;
 175         struct nfs4_deviceid *d_id;
 176         struct objio_dev_ent *ode;
 177         struct osd_dev *od;
 178         struct osd_dev_info odi;
 179         int err;
 180
 181         d_id = &objio_seg->comps[comp].oc_object_id.oid_device_id;
 182
 183         ode = _dev_list_find(NFS_SERVER(pnfslay->plh_inode), d_id);
 184         if (ode)
 185                 return ode;
 186
 187         err = objlayout_get_deviceinfo(pnfslay, d_id, &deviceaddr, gfp_flags);
 188         if (unlikely(err)) {
 189                 dprintk("%s: objlayout_get_deviceinfo dev(%llx:%llx) =>%d\n",
 190                         __func__, _DEVID_LO(d_id), _DEVID_HI(d_id), err);
 191                 return ERR_PTR(err);
 192         }
 193
 194         odi.systemid_len = deviceaddr->oda_systemid.len;
 195         if (odi.systemid_len > sizeof(odi.systemid)) {
 196                 err = -EINVAL;
 197                 goto out;
 198         } else if (odi.systemid_len)
 199                 memcpy(odi.systemid, deviceaddr->oda_systemid.data,
 200                        odi.systemid_len);
 201         odi.osdname_len  = deviceaddr->oda_osdname.len;
 202         odi.osdname      = (u8 *)deviceaddr->oda_osdname.data;
 203
 204         if (!odi.osdname_len && !odi.systemid_len) {
 205                 dprintk("%s: !odi.osdname_len && !odi.systemid_len\n",
 206                         __func__);
 207                 err = -ENODEV;
 208                 goto out;
 209         }
 210
 211         od = osduld_info_lookup(&odi);
 212         if (unlikely(IS_ERR(od))) {
 213                 err = PTR_ERR(od);
 214                 dprintk("%s: osduld_info_lookup => %d\n", __func__, err);
 215                 goto out;
 216         }
 217
 218         ode = _dev_list_add(NFS_SERVER(pnfslay->plh_inode), d_id, od,
 219                             gfp_flags);
 220
 221 out:
 222         dprintk("%s: return=%d\n", __func__, err);
 223         objlayout_put_deviceinfo(deviceaddr);
 224         return err ? ERR_PTR(err) : ode;
 225 }
 226
 227 static int objio_devices_lookup(struct pnfs_layout_hdr *pnfslay,
 228         struct objio_segment *objio_seg,
 229         gfp_t gfp_flags)
 230 {
 231         unsigned i;
 232         int err;
 233
 234         /* lookup all devices */
 235         for (i = 0; i < objio_seg->num_comps; i++) {
 236                 struct objio_dev_ent *ode;
 237
 238                 ode = _device_lookup(pnfslay, objio_seg, i, gfp_flags);
 239                 if (unlikely(IS_ERR(ode))) {
 240                         err = PTR_ERR(ode);
 241                         goto out;
 242                 }
 243                 objio_seg->ods[i] = ode;
 244         }
 245         err = 0;
 246
 247 out:
 248         dprintk("%s: return=%d\n", __func__, err);
 249         return err;
 250 }
 251
 252 static int _verify_data_map(struct pnfs_osd_layout *layout)
 253 {
 254         struct pnfs_osd_data_map *data_map = &layout->olo_map;
 255         u64 stripe_length;
 256         u32 group_width;
 257
 258 /* FIXME: Only raid0 for now. if not go through MDS */
 259         if (data_map->odm_raid_algorithm != PNFS_OSD_RAID_0) {
 260                 printk(KERN_ERR "Only RAID_0 for now\n");
 261                 return -ENOTSUPP;
 262         }
 263         if (0 != (data_map->odm_num_comps % (data_map->odm_mirror_cnt + 1))) {
 264                 printk(KERN_ERR "Data Map wrong, num_comps=%u mirrors=%u\n",
 265                           data_map->odm_num_comps, data_map->odm_mirror_cnt);
 266                 return -EINVAL;
 267         }
 268
 269         if (data_map->odm_group_width)
 270                 group_width = data_map->odm_group_width;
 271         else
 272                 group_width = data_map->odm_num_comps /
 273                                                 (data_map->odm_mirror_cnt + 1);
 274
 275         stripe_length = (u64)data_map->odm_stripe_unit * group_width;
 276         if (stripe_length >= (1ULL << 32)) {
 277                 printk(KERN_ERR "Total Stripe length(0x%llx)"
 278                           " >= 32bit is not supported\n", _LLU(stripe_length));
 279                 return -ENOTSUPP;
 280         }
 281
 282         if (0 != (data_map->odm_stripe_unit & ~PAGE_MASK)) {
 283                 printk(KERN_ERR "Stripe Unit(0x%llx)"
 284                           " must be Multples of PAGE_SIZE(0x%lx)\n",
 285                           _LLU(data_map->odm_stripe_unit), PAGE_SIZE);
 286                 return -ENOTSUPP;
 287         }
 288
 289         return 0;
 290 }
 291
 292 static void copy_single_comp(struct pnfs_osd_object_cred *cur_comp,
 293                              struct pnfs_osd_object_cred *src_comp,
 294                              struct caps_buffers *caps_p)
 295 {
 296         WARN_ON(src_comp->oc_cap_key.cred_len > sizeof(caps_p->caps_key));
 297         WARN_ON(src_comp->oc_cap.cred_len > sizeof(caps_p->creds));
 298
 299         *cur_comp = *src_comp;
 300
 301         memcpy(caps_p->caps_key, src_comp->oc_cap_key.cred,
 302                sizeof(caps_p->caps_key));
 303         cur_comp->oc_cap_key.cred = caps_p->caps_key;
 304
 305         memcpy(caps_p->creds, src_comp->oc_cap.cred,
 306                sizeof(caps_p->creds));
 307         cur_comp->oc_cap.cred = caps_p->creds;
 308 }
 309
 310 int objio_alloc_lseg(struct pnfs_layout_segment **outp,
 311         struct pnfs_layout_hdr *pnfslay,
 312         struct pnfs_layout_range *range,
 313         struct xdr_stream *xdr,
 314         gfp_t gfp_flags)
 315 {
 316         struct objio_segment *objio_seg;
 317         struct pnfs_osd_xdr_decode_layout_iter iter;
 318         struct pnfs_osd_layout layout;
 319         struct pnfs_osd_object_cred *cur_comp, src_comp;
 320         struct caps_buffers *caps_p;
 321         int err;
 322
 323         err = pnfs_osd_xdr_decode_layout_map(&layout, &iter, xdr);
 324         if (unlikely(err))
 325                 return err;
 326
 327         err = _verify_data_map(&layout);
 328         if (unlikely(err))
 329                 return err;
 330
 331         objio_seg = kzalloc(sizeof(*objio_seg) +
 332                             sizeof(objio_seg->ods[0]) * layout.olo_num_comps +
 333                             sizeof(*objio_seg->comps) * layout.olo_num_comps +
 334                             sizeof(struct caps_buffers) * layout.olo_num_comps,
 335                             gfp_flags);
 336         if (!objio_seg)
 337                 return -ENOMEM;
 338
 339         objio_seg->comps = (void *)(objio_seg->ods + layout.olo_num_comps);
 340         cur_comp = objio_seg->comps;
 341         caps_p = (void *)(cur_comp + layout.olo_num_comps);
 342         while (pnfs_osd_xdr_decode_layout_comp(&src_comp, &iter, xdr, &err))
 343                 copy_single_comp(cur_comp++, &src_comp, caps_p++);
 344         if (unlikely(err))
 345                 goto err;
 346
 347         objio_seg->num_comps = layout.olo_num_comps;
 348         objio_seg->comps_index = layout.olo_comps_index;
 349         err = objio_devices_lookup(pnfslay, objio_seg, gfp_flags);
 350         if (err)
 351                 goto err;
 352
 353         objio_seg->mirrors_p1 = layout.olo_map.odm_mirror_cnt + 1;
 354         objio_seg->stripe_unit = layout.olo_map.odm_stripe_unit;
 355         if (layout.olo_map.odm_group_width) {
 356                 objio_seg->group_width = layout.olo_map.odm_group_width;
 357                 objio_seg->group_depth = layout.olo_map.odm_group_depth;
 358                 objio_seg->group_count = layout.olo_map.odm_num_comps /
 359                                                 objio_seg->mirrors_p1 /
 360                                                 objio_seg->group_width;
 361         } else {
 362                 objio_seg->group_width = layout.olo_map.odm_num_comps /
 363                                                 objio_seg->mirrors_p1;
 364                 objio_seg->group_depth = -1;
 365                 objio_seg->group_count = 1;
 366         }
 367
 368         *outp = &objio_seg->lseg;
 369         return 0;
 370
 371 err:
 372         kfree(objio_seg);
 373         dprintk("%s: Error: return %d\n", __func__, err);
 374         *outp = NULL;
 375         return err;
 376 }
 377
 378 void objio_free_lseg(struct pnfs_layout_segment *lseg)
 379 {
 380         int i;
 381         struct objio_segment *objio_seg = OBJIO_LSEG(lseg);
 382
 383         for (i = 0; i < objio_seg->num_comps; i++) {
 384                 if (!objio_seg->ods[i])
 385                         break;
 386                 nfs4_put_deviceid_node(&objio_seg->ods[i]->id_node);
 387         }
 388         kfree(objio_seg);
 389 }
 390
 391 int objio_alloc_io_state(struct pnfs_layout_segment *lseg,
 392                          struct objlayout_io_state **outp,
 393                          gfp_t gfp_flags)
 394 {
 395         struct objio_segment *objio_seg = OBJIO_LSEG(lseg);
 396         struct objio_state *ios;
 397         const unsigned first_size = sizeof(*ios) +
 398                                 objio_seg->num_comps * sizeof(ios->per_dev[0]);
 399
 400         ios = kzalloc(first_size, gfp_flags);
 401         if (unlikely(!ios))
 402                 return -ENOMEM;
 403
 404         ios->layout = objio_seg;
 405
 406         *outp = &ios->ol_state;
 407         return 0;
 408 }
 409
 410 void objio_free_io_state(struct objlayout_io_state *ol_state)
 411 {
 412         struct objio_state *ios = container_of(ol_state, struct objio_state,
 413                                                ol_state);
 414
 415         kfree(ios);
 416 }
 417
 418 static void _clear_bio(struct bio *bio)
 419 {
 420         struct bio_vec *bv;
 421         unsigned i;
 422
 423         __bio_for_each_segment(bv, bio, i, 0) {
 424                 unsigned this_count = bv->bv_len;
 425
 426                 if (likely(PAGE_SIZE == this_count))
 427                         clear_highpage(bv->bv_page);
 428                 else
 429                         zero_user(bv->bv_page, bv->bv_offset, this_count);
 430         }
 431 }
 432
 433 static int _io_check(struct objio_state *ios, bool is_write)
 434 {
 435         enum osd_err_priority oep = OSD_ERR_PRI_NO_ERROR;
 436         int lin_ret = 0;
 437         int i;
 438
 439         for (i = 0; i <  ios->numdevs; i++) {
 440                 struct osd_sense_info osi;
 441                 struct osd_request *or = ios->per_dev[i].or;
 442                 unsigned dev;
 443                 int ret;
 444
 445                 if (!or)
 446                         continue;
 447
 448                 ret = osd_req_decode_sense(or, &osi);
 449                 if (likely(!ret))
 450                         continue;
 451
 452                 if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) {
 453                         /* start read offset passed endof file */
 454                         BUG_ON(is_write);
 455                         _clear_bio(ios->per_dev[i].bio);
 456                         dprintk("%s: start read offset passed end of file "
 457                                 "offset=0x%llx, length=0x%lx\n", __func__,
 458                                 _LLU(ios->per_dev[i].offset),
 459                                 ios->per_dev[i].length);
 460
 461                         continue; /* we recovered */
 462                 }
 463                 dev = ios->per_dev[i].dev;
 464
 465                 if (osi.osd_err_pri >= oep) {
 466                         oep = osi.osd_err_pri;
 467                         lin_ret = ret;
 468                 }
 469         }
 470
 471         return lin_ret;
 472 }
 473
 474 /*
 475  * Common IO state helpers.
 476  */
 477 static void _io_free(struct objio_state *ios)
 478 {
 479         unsigned i;
 480
 481         for (i = 0; i < ios->numdevs; i++) {
 482                 struct _objio_per_comp *per_dev = &ios->per_dev[i];
 483
 484                 if (per_dev->or) {
 485                         osd_end_request(per_dev->or);
 486                         per_dev->or = NULL;
 487                 }
 488
 489                 if (per_dev->bio) {
 490                         bio_put(per_dev->bio);
 491                         per_dev->bio = NULL;
 492                 }
 493         }
 494 }
 495
 496 struct osd_dev *_io_od(struct objio_state *ios, unsigned dev)
 497 {
 498         unsigned min_dev = ios->layout->comps_index;
 499         unsigned max_dev = min_dev + ios->layout->num_comps;
 500
 501         BUG_ON(dev < min_dev || max_dev <= dev);
 502         return ios->layout->ods[dev - min_dev]->od;
 503 }
 504
 505 struct _striping_info {
 506         u64 obj_offset;
 507         u64 group_length;
 508         unsigned dev;
 509         unsigned unit_off;
 510 };
 511
 512 static void _calc_stripe_info(struct objio_state *ios, u64 file_offset,
 513                               struct _striping_info *si)
 514 {
 515         u32     stripe_unit = ios->layout->stripe_unit;
 516         u32     group_width = ios->layout->group_width;
 517         u64     group_depth = ios->layout->group_depth;
 518         u32     U = stripe_unit * group_width;
 519
 520         u64     T = U * group_depth;
 521         u64     S = T * ios->layout->group_count;
 522         u64     M = div64_u64(file_offset, S);
 523
 524         /*
 525         G = (L - (M * S)) / T
 526         H = (L - (M * S)) % T
 527         */
 528         u64     LmodU = file_offset - M * S;
 529         u32     G = div64_u64(LmodU, T);
 530         u64     H = LmodU - G * T;
 531
 532         u32     N = div_u64(H, U);
 533
 534         div_u64_rem(file_offset, stripe_unit, &si->unit_off);
 535         si->obj_offset = si->unit_off + (N * stripe_unit) +
 536                                   (M * group_depth * stripe_unit);
 537
 538         /* "H - (N * U)" is just "H % U" so it's bound to u32 */
 539         si->dev = (u32)(H - (N * U)) / stripe_unit + G * group_width;
 540         si->dev *= ios->layout->mirrors_p1;
 541
 542         si->group_length = T - H;
 543 }
 544
 545 static int _add_stripe_unit(struct objio_state *ios,  unsigned *cur_pg,
 546                 unsigned pgbase, struct _objio_per_comp *per_dev, int cur_len,
 547                 gfp_t gfp_flags)
 548 {
 549         unsigned pg = *cur_pg;
 550         struct request_queue *q =
 551                         osd_request_queue(_io_od(ios, per_dev->dev));
 552
 553         per_dev->length += cur_len;
 554
 555         if (per_dev->bio == NULL) {
 556                 unsigned stripes = ios->layout->num_comps /
 557                                                      ios->layout->mirrors_p1;
 558                 unsigned pages_in_stripe = stripes *
 559                                       (ios->layout->stripe_unit / PAGE_SIZE);
 560                 unsigned bio_size = (ios->ol_state.nr_pages + pages_in_stripe) /
 561                                     stripes;
 562
 563                 if (BIO_MAX_PAGES_KMALLOC < bio_size)
 564                         bio_size = BIO_MAX_PAGES_KMALLOC;
 565
 566                 per_dev->bio = bio_kmalloc(gfp_flags, bio_size);
 567                 if (unlikely(!per_dev->bio)) {
 568                         dprintk("Faild to allocate BIO size=%u\n", bio_size);
 569                         return -ENOMEM;
 570                 }
 571         }
 572
 573         while (cur_len > 0) {
 574                 unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
 575                 unsigned added_len;
 576
 577                 BUG_ON(ios->ol_state.nr_pages <= pg);
 578                 cur_len -= pglen;
 579
 580                 added_len = bio_add_pc_page(q, per_dev->bio,
 581                                         ios->ol_state.pages[pg], pglen, pgbase);
 582                 if (unlikely(pglen != added_len))
 583                         return -ENOMEM;
 584                 pgbase = 0;
 585                 ++pg;
 586         }
 587         BUG_ON(cur_len);
 588
 589         *cur_pg = pg;
 590         return 0;
 591 }
 592
 593 static int _prepare_one_group(struct objio_state *ios, u64 length,
 594                               struct _striping_info *si, unsigned *last_pg,
 595                               gfp_t gfp_flags)
 596 {
 597         unsigned stripe_unit = ios->layout->stripe_unit;
 598         unsigned mirrors_p1 = ios->layout->mirrors_p1;
 599         unsigned devs_in_group = ios->layout->group_width * mirrors_p1;
 600         unsigned dev = si->dev;
 601         unsigned first_dev = dev - (dev % devs_in_group);
 602         unsigned max_comp = ios->numdevs ? ios->numdevs - mirrors_p1 : 0;
 603         unsigned cur_pg = *last_pg;
 604         int ret = 0;
 605
 606         while (length) {
 607                 struct _objio_per_comp *per_dev = &ios->per_dev[dev];
 608                 unsigned cur_len, page_off = 0;
 609
 610                 if (!per_dev->length) {
 611                         per_dev->dev = dev;
 612                         if (dev < si->dev) {
 613                                 per_dev->offset = si->obj_offset + stripe_unit -
 614                                                                    si->unit_off;
 615                                 cur_len = stripe_unit;
 616                         } else if (dev == si->dev) {
 617                                 per_dev->offset = si->obj_offset;
 618                                 cur_len = stripe_unit - si->unit_off;
 619                                 page_off = si->unit_off & ~PAGE_MASK;
 620                                 BUG_ON(page_off &&
 621                                       (page_off != ios->ol_state.pgbase));
 622                         } else { /* dev > si->dev */
 623                                 per_dev->offset = si->obj_offset - si->unit_off;
 624                                 cur_len = stripe_unit;
 625                         }
 626
 627                         if (max_comp < dev)
 628                                 max_comp = dev;
 629                 } else {
 630                         cur_len = stripe_unit;
 631                 }
 632                 if (cur_len >= length)
 633                         cur_len = length;
 634
 635                 ret = _add_stripe_unit(ios, &cur_pg, page_off , per_dev,
 636                                        cur_len, gfp_flags);
 637                 if (unlikely(ret))
 638                         goto out;
 639
 640                 dev += mirrors_p1;
 641                 dev = (dev % devs_in_group) + first_dev;
 642
 643                 length -= cur_len;
 644                 ios->length += cur_len;
 645         }
 646 out:
 647         ios->numdevs = max_comp + mirrors_p1;
 648         *last_pg = cur_pg;
 649         return ret;
 650 }
 651
 652 static int _io_rw_pagelist(struct objio_state *ios, gfp_t gfp_flags)
 653 {
 654         u64 length = ios->ol_state.count;
 655         u64 offset = ios->ol_state.offset;
 656         struct _striping_info si;
 657         unsigned last_pg = 0;
 658         int ret = 0;
 659
 660         while (length) {
 661                 _calc_stripe_info(ios, offset, &si);
 662
 663                 if (length < si.group_length)
 664                         si.group_length = length;
 665
 666                 ret = _prepare_one_group(ios, si.group_length, &si, &last_pg, gfp_flags);
 667                 if (unlikely(ret))
 668                         goto out;
 669
 670                 offset += si.group_length;
 671                 length -= si.group_length;
 672         }
 673
 674 out:
 675         if (!ios->length)
 676                 return ret;
 677
 678         return 0;
 679 }
 680
 681 static ssize_t _sync_done(struct objio_state *ios)
 682 {
 683         struct completion *waiting = ios->private;
 684
 685         complete(waiting);
 686         return 0;
 687 }
 688
 689 static void _last_io(struct kref *kref)
 690 {
 691         struct objio_state *ios = container_of(kref, struct objio_state, kref);
 692
 693         ios->done(ios);
 694 }
 695
 696 static void _done_io(struct osd_request *or, void *p)
 697 {
 698         struct objio_state *ios = p;
 699
 700         kref_put(&ios->kref, _last_io);
 701 }
 702
 703 static ssize_t _io_exec(struct objio_state *ios)
 704 {
 705         DECLARE_COMPLETION_ONSTACK(wait);
 706         ssize_t status = 0; /* sync status */
 707         unsigned i;
 708         objio_done_fn saved_done_fn = ios->done;
 709         bool sync = ios->ol_state.sync;
 710
 711         if (sync) {
 712                 ios->done = _sync_done;
 713                 ios->private = &wait;
 714         }
 715
 716         kref_init(&ios->kref);
 717
 718         for (i = 0; i < ios->numdevs; i++) {
 719                 struct osd_request *or = ios->per_dev[i].or;
 720
 721                 if (!or)
 722                         continue;
 723
 724                 kref_get(&ios->kref);
 725                 osd_execute_request_async(or, _done_io, ios);
 726         }
 727
 728         kref_put(&ios->kref, _last_io);
 729
 730         if (sync) {
 731                 wait_for_completion(&wait);
 732                 status = saved_done_fn(ios);
 733         }
 734
 735         return status;
 736 }
 737
 738 /*
 739  * read
 740  */
 741 static ssize_t _read_done(struct objio_state *ios)
 742 {
 743         ssize_t status;
 744         int ret = _io_check(ios, false);
 745
 746         _io_free(ios);
 747
 748         if (likely(!ret))
 749                 status = ios->length;
 750         else
 751                 status = ret;
 752
 753         objlayout_read_done(&ios->ol_state, status, ios->ol_state.sync);
 754         return status;
 755 }
 756
 757 static int _read_mirrors(struct objio_state *ios, unsigned cur_comp)
 758 {
 759         struct osd_request *or = NULL;
 760         struct _objio_per_comp *per_dev = &ios->per_dev[cur_comp];
 761         unsigned dev = per_dev->dev;
 762         struct pnfs_osd_object_cred *cred =
 763                         &ios->layout->comps[dev];
 764         struct osd_obj_id obj = {
 765                 .partition = cred->oc_object_id.oid_partition_id,
 766                 .id = cred->oc_object_id.oid_object_id,
 767         };
 768         int ret;
 769
 770         or = osd_start_request(_io_od(ios, dev), GFP_KERNEL);
 771         if (unlikely(!or)) {
 772                 ret = -ENOMEM;
 773                 goto err;
 774         }
 775         per_dev->or = or;
 776
 777         osd_req_read(or, &obj, per_dev->offset, per_dev->bio, per_dev->length);
 778
 779         ret = osd_finalize_request(or, 0, cred->oc_cap.cred, NULL);
 780         if (ret) {
 781                 dprintk("%s: Faild to osd_finalize_request() => %d\n",
 782                         __func__, ret);
 783                 goto err;
 784         }
 785
 786         dprintk("%s:[%d] dev=%d obj=0x%llx start=0x%llx length=0x%lx\n",
 787                 __func__, cur_comp, dev, obj.id, _LLU(per_dev->offset),
 788                 per_dev->length);
 789
 790 err:
 791         return ret;
 792 }
 793
 794 static ssize_t _read_exec(struct objio_state *ios)
 795 {
 796         unsigned i;
 797         int ret;
 798
 799         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 800                 if (!ios->per_dev[i].length)
 801                         continue;
 802                 ret = _read_mirrors(ios, i);
 803                 if (unlikely(ret))
 804                         goto err;
 805         }
 806
 807         ios->done = _read_done;
 808         return _io_exec(ios); /* In sync mode exec returns the io status */
 809
 810 err:
 811         _io_free(ios);
 812         return ret;
 813 }
 814
 815 ssize_t objio_read_pagelist(struct objlayout_io_state *ol_state)
 816 {
 817         struct objio_state *ios = container_of(ol_state, struct objio_state,
 818                                                ol_state);
 819         int ret;
 820
 821         ret = _io_rw_pagelist(ios, GFP_KERNEL);
 822         if (unlikely(ret))
 823                 return ret;
 824
 825         return _read_exec(ios);
 826 }
 827
 828 /*
 829  * write
 830  */
 831 static ssize_t _write_done(struct objio_state *ios)
 832 {
 833         ssize_t status;
 834         int ret = _io_check(ios, true);
 835
 836         _io_free(ios);
 837
 838         if (likely(!ret)) {
 839                 /* FIXME: should be based on the OSD's persistence model
 840                  * See OSD2r05 Section 4.13 Data persistence model */
 841                 ios->ol_state.committed = NFS_FILE_SYNC;
 842                 status = ios->length;
 843         } else {
 844                 status = ret;
 845         }
 846
 847         objlayout_write_done(&ios->ol_state, status, ios->ol_state.sync);
 848         return status;
 849 }
 850
 851 static int _write_mirrors(struct objio_state *ios, unsigned cur_comp)
 852 {
 853         struct _objio_per_comp *master_dev = &ios->per_dev[cur_comp];
 854         unsigned dev = ios->per_dev[cur_comp].dev;
 855         unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
 856         int ret;
 857
 858         for (; cur_comp < last_comp; ++cur_comp, ++dev) {
 859                 struct osd_request *or = NULL;
 860                 struct pnfs_osd_object_cred *cred =
 861                                         &ios->layout->comps[dev];
 862                 struct osd_obj_id obj = {
 863                         .partition = cred->oc_object_id.oid_partition_id,
 864                         .id = cred->oc_object_id.oid_object_id,
 865                 };
 866                 struct _objio_per_comp *per_dev = &ios->per_dev[cur_comp];
 867                 struct bio *bio;
 868
 869                 or = osd_start_request(_io_od(ios, dev), GFP_NOFS);
 870                 if (unlikely(!or)) {
 871                         ret = -ENOMEM;
 872                         goto err;
 873                 }
 874                 per_dev->or = or;
 875
 876                 if (per_dev != master_dev) {
 877                         bio = bio_kmalloc(GFP_NOFS,
 878                                           master_dev->bio->bi_max_vecs);
 879                         if (unlikely(!bio)) {
 880                                 dprintk("Faild to allocate BIO size=%u\n",
 881                                         master_dev->bio->bi_max_vecs);
 882                                 ret = -ENOMEM;
 883                                 goto err;
 884                         }
 885
 886                         __bio_clone(bio, master_dev->bio);
 887                         bio->bi_bdev = NULL;
 888                         bio->bi_next = NULL;
 889                         per_dev->bio = bio;
 890                         per_dev->dev = dev;
 891                         per_dev->length = master_dev->length;
 892                         per_dev->offset =  master_dev->offset;
 893                 } else {
 894                         bio = master_dev->bio;
 895                         bio->bi_rw |= REQ_WRITE;
 896                 }
 897
 898                 osd_req_write(or, &obj, per_dev->offset, bio, per_dev->length);
 899
 900                 ret = osd_finalize_request(or, 0, cred->oc_cap.cred, NULL);
 901                 if (ret) {
 902                         dprintk("%s: Faild to osd_finalize_request() => %d\n",
 903                                 __func__, ret);
 904                         goto err;
 905                 }
 906
 907                 dprintk("%s:[%d] dev=%d obj=0x%llx start=0x%llx length=0x%lx\n",
 908                         __func__, cur_comp, dev, obj.id, _LLU(per_dev->offset),
 909                         per_dev->length);
 910         }
 911
 912 err:
 913         return ret;
 914 }
 915
 916 static ssize_t _write_exec(struct objio_state *ios)
 917 {
 918         unsigned i;
 919         int ret;
 920
 921         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 922                 if (!ios->per_dev[i].length)
 923                         continue;
 924                 ret = _write_mirrors(ios, i);
 925                 if (unlikely(ret))
 926                         goto err;
 927         }
 928
 929         ios->done = _write_done;
 930         return _io_exec(ios); /* In sync mode exec returns the io->status */
 931
 932 err:
 933         _io_free(ios);
 934         return ret;
 935 }
 936
 937 ssize_t objio_write_pagelist(struct objlayout_io_state *ol_state, bool stable)
 938 {
 939         struct objio_state *ios = container_of(ol_state, struct objio_state,
 940                                                ol_state);
 941         int ret;
 942
 943         /* TODO: ios->stable = stable; */
 944         ret = _io_rw_pagelist(ios, GFP_NOFS);
 945         if (unlikely(ret))
 946                 return ret;
 947
 948         return _write_exec(ios);
 949 }
 950
 951 /*
 952  * objlayout_pg_test(). Called by nfs_can_coalesce_requests()
 953  *
 954  * return 1 :  coalesce page
 955  * return 0 :  don't coalesce page
 956  */
 957 int
 958 objlayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 959                    struct nfs_page *req)
 960 {
 961         return 1;
 962 }
 963
 964 static struct pnfs_layoutdriver_type objlayout_type = {
 965         .id = LAYOUT_OSD2_OBJECTS,
 966         .name = "LAYOUT_OSD2_OBJECTS",
 967
 968         .alloc_layout_hdr        = objlayout_alloc_layout_hdr,
 969         .free_layout_hdr         = objlayout_free_layout_hdr,
 970
 971         .alloc_lseg              = objlayout_alloc_lseg,
 972         .free_lseg               = objlayout_free_lseg,
 973
 974         .read_pagelist           = objlayout_read_pagelist,
 975         .write_pagelist          = objlayout_write_pagelist,
 976         .pg_test                 = objlayout_pg_test,
 977
 978         .free_deviceid_node      = objio_free_deviceid_node,
 979 };
 980
 981 MODULE_DESCRIPTION("pNFS Layout Driver for OSD2 objects");
 982 MODULE_AUTHOR("Benny Halevy <bhalevy@panasas.com>");
 983 MODULE_LICENSE("GPL");
 984
 985 static int __init
 986 objlayout_init(void)
 987 {
 988         int ret = pnfs_register_layoutdriver(&objlayout_type);
 989
 990         if (ret)
 991                 printk(KERN_INFO
 992                         "%s: Registering OSD pNFS Layout Driver failed: error=%d\n",
 993                         __func__, ret);
 994         else
 995                 printk(KERN_INFO "%s: Registered OSD pNFS Layout Driver\n",
 996                         __func__);
 997         return ret;
 998 }
 999
1000 static void __exit
1001 objlayout_exit(void)
1002 {
1003         pnfs_unregister_layoutdriver(&objlayout_type);
1004         printk(KERN_INFO "%s: Unregistered OSD pNFS Layout Driver\n",
1005                __func__);
1006 }
1007
1008 module_init(objlayout_init);
1009 module_exit(objlayout_exit);