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 max_io_size;
 132
 133         unsigned comps_index;
 134         unsigned num_comps;
 135         /* variable length */
 136         struct objio_dev_ent *ods[];
 137 };
 138
 139 static inline struct objio_segment *
 140 OBJIO_LSEG(struct pnfs_layout_segment *lseg)
 141 {
 142         return container_of(lseg, struct objio_segment, lseg);
 143 }
 144
 145 struct objio_state;
 146 typedef ssize_t (*objio_done_fn)(struct objio_state *ios);
 147
 148 struct objio_state {
 149         /* Generic layer */
 150         struct objlayout_io_state ol_state;
 151
 152         struct objio_segment *layout;
 153
 154         struct kref kref;
 155         objio_done_fn done;
 156         void *private;
 157
 158         unsigned long length;
 159         unsigned numdevs; /* Actually used devs in this IO */
 160         /* A per-device variable array of size numdevs */
 161         struct _objio_per_comp {
 162                 struct bio *bio;
 163                 struct osd_request *or;
 164                 unsigned long length;
 165                 u64 offset;
 166                 unsigned dev;
 167         } per_dev[];
 168 };
 169
 170 /* Send and wait for a get_device_info of devices in the layout,
 171    then look them up with the osd_initiator library */
 172 static struct objio_dev_ent *_device_lookup(struct pnfs_layout_hdr *pnfslay,
 173                                 struct objio_segment *objio_seg, unsigned comp,
 174                                 gfp_t gfp_flags)
 175 {
 176         struct pnfs_osd_deviceaddr *deviceaddr;
 177         struct nfs4_deviceid *d_id;
 178         struct objio_dev_ent *ode;
 179         struct osd_dev *od;
 180         struct osd_dev_info odi;
 181         int err;
 182
 183         d_id = &objio_seg->comps[comp].oc_object_id.oid_device_id;
 184
 185         ode = _dev_list_find(NFS_SERVER(pnfslay->plh_inode), d_id);
 186         if (ode)
 187                 return ode;
 188
 189         err = objlayout_get_deviceinfo(pnfslay, d_id, &deviceaddr, gfp_flags);
 190         if (unlikely(err)) {
 191                 dprintk("%s: objlayout_get_deviceinfo dev(%llx:%llx) =>%d\n",
 192                         __func__, _DEVID_LO(d_id), _DEVID_HI(d_id), err);
 193                 return ERR_PTR(err);
 194         }
 195
 196         odi.systemid_len = deviceaddr->oda_systemid.len;
 197         if (odi.systemid_len > sizeof(odi.systemid)) {
 198                 err = -EINVAL;
 199                 goto out;
 200         } else if (odi.systemid_len)
 201                 memcpy(odi.systemid, deviceaddr->oda_systemid.data,
 202                        odi.systemid_len);
 203         odi.osdname_len  = deviceaddr->oda_osdname.len;
 204         odi.osdname      = (u8 *)deviceaddr->oda_osdname.data;
 205
 206         if (!odi.osdname_len && !odi.systemid_len) {
 207                 dprintk("%s: !odi.osdname_len && !odi.systemid_len\n",
 208                         __func__);
 209                 err = -ENODEV;
 210                 goto out;
 211         }
 212
 213         od = osduld_info_lookup(&odi);
 214         if (unlikely(IS_ERR(od))) {
 215                 err = PTR_ERR(od);
 216                 dprintk("%s: osduld_info_lookup => %d\n", __func__, err);
 217                 goto out;
 218         }
 219
 220         ode = _dev_list_add(NFS_SERVER(pnfslay->plh_inode), d_id, od,
 221                             gfp_flags);
 222
 223 out:
 224         dprintk("%s: return=%d\n", __func__, err);
 225         objlayout_put_deviceinfo(deviceaddr);
 226         return err ? ERR_PTR(err) : ode;
 227 }
 228
 229 static int objio_devices_lookup(struct pnfs_layout_hdr *pnfslay,
 230         struct objio_segment *objio_seg,
 231         gfp_t gfp_flags)
 232 {
 233         unsigned i;
 234         int err;
 235
 236         /* lookup all devices */
 237         for (i = 0; i < objio_seg->num_comps; i++) {
 238                 struct objio_dev_ent *ode;
 239
 240                 ode = _device_lookup(pnfslay, objio_seg, i, gfp_flags);
 241                 if (unlikely(IS_ERR(ode))) {
 242                         err = PTR_ERR(ode);
 243                         goto out;
 244                 }
 245                 objio_seg->ods[i] = ode;
 246         }
 247         err = 0;
 248
 249 out:
 250         dprintk("%s: return=%d\n", __func__, err);
 251         return err;
 252 }
 253
 254 static int _verify_data_map(struct pnfs_osd_layout *layout)
 255 {
 256         struct pnfs_osd_data_map *data_map = &layout->olo_map;
 257         u64 stripe_length;
 258         u32 group_width;
 259
 260 /* FIXME: Only raid0 for now. if not go through MDS */
 261         if (data_map->odm_raid_algorithm != PNFS_OSD_RAID_0) {
 262                 printk(KERN_ERR "Only RAID_0 for now\n");
 263                 return -ENOTSUPP;
 264         }
 265         if (0 != (data_map->odm_num_comps % (data_map->odm_mirror_cnt + 1))) {
 266                 printk(KERN_ERR "Data Map wrong, num_comps=%u mirrors=%u\n",
 267                           data_map->odm_num_comps, data_map->odm_mirror_cnt);
 268                 return -EINVAL;
 269         }
 270
 271         if (data_map->odm_group_width)
 272                 group_width = data_map->odm_group_width;
 273         else
 274                 group_width = data_map->odm_num_comps /
 275                                                 (data_map->odm_mirror_cnt + 1);
 276
 277         stripe_length = (u64)data_map->odm_stripe_unit * group_width;
 278         if (stripe_length >= (1ULL << 32)) {
 279                 printk(KERN_ERR "Total Stripe length(0x%llx)"
 280                           " >= 32bit is not supported\n", _LLU(stripe_length));
 281                 return -ENOTSUPP;
 282         }
 283
 284         if (0 != (data_map->odm_stripe_unit & ~PAGE_MASK)) {
 285                 printk(KERN_ERR "Stripe Unit(0x%llx)"
 286                           " must be Multples of PAGE_SIZE(0x%lx)\n",
 287                           _LLU(data_map->odm_stripe_unit), PAGE_SIZE);
 288                 return -ENOTSUPP;
 289         }
 290
 291         return 0;
 292 }
 293
 294 static void copy_single_comp(struct pnfs_osd_object_cred *cur_comp,
 295                              struct pnfs_osd_object_cred *src_comp,
 296                              struct caps_buffers *caps_p)
 297 {
 298         WARN_ON(src_comp->oc_cap_key.cred_len > sizeof(caps_p->caps_key));
 299         WARN_ON(src_comp->oc_cap.cred_len > sizeof(caps_p->creds));
 300
 301         *cur_comp = *src_comp;
 302
 303         memcpy(caps_p->caps_key, src_comp->oc_cap_key.cred,
 304                sizeof(caps_p->caps_key));
 305         cur_comp->oc_cap_key.cred = caps_p->caps_key;
 306
 307         memcpy(caps_p->creds, src_comp->oc_cap.cred,
 308                sizeof(caps_p->creds));
 309         cur_comp->oc_cap.cred = caps_p->creds;
 310 }
 311
 312 int objio_alloc_lseg(struct pnfs_layout_segment **outp,
 313         struct pnfs_layout_hdr *pnfslay,
 314         struct pnfs_layout_range *range,
 315         struct xdr_stream *xdr,
 316         gfp_t gfp_flags)
 317 {
 318         struct objio_segment *objio_seg;
 319         struct pnfs_osd_xdr_decode_layout_iter iter;
 320         struct pnfs_osd_layout layout;
 321         struct pnfs_osd_object_cred *cur_comp, src_comp;
 322         struct caps_buffers *caps_p;
 323         int err;
 324
 325         err = pnfs_osd_xdr_decode_layout_map(&layout, &iter, xdr);
 326         if (unlikely(err))
 327                 return err;
 328
 329         err = _verify_data_map(&layout);
 330         if (unlikely(err))
 331                 return err;
 332
 333         objio_seg = kzalloc(sizeof(*objio_seg) +
 334                             sizeof(objio_seg->ods[0]) * layout.olo_num_comps +
 335                             sizeof(*objio_seg->comps) * layout.olo_num_comps +
 336                             sizeof(struct caps_buffers) * layout.olo_num_comps,
 337                             gfp_flags);
 338         if (!objio_seg)
 339                 return -ENOMEM;
 340
 341         objio_seg->comps = (void *)(objio_seg->ods + layout.olo_num_comps);
 342         cur_comp = objio_seg->comps;
 343         caps_p = (void *)(cur_comp + layout.olo_num_comps);
 344         while (pnfs_osd_xdr_decode_layout_comp(&src_comp, &iter, xdr, &err))
 345                 copy_single_comp(cur_comp++, &src_comp, caps_p++);
 346         if (unlikely(err))
 347                 goto err;
 348
 349         objio_seg->num_comps = layout.olo_num_comps;
 350         objio_seg->comps_index = layout.olo_comps_index;
 351         err = objio_devices_lookup(pnfslay, objio_seg, gfp_flags);
 352         if (err)
 353                 goto err;
 354
 355         objio_seg->mirrors_p1 = layout.olo_map.odm_mirror_cnt + 1;
 356         objio_seg->stripe_unit = layout.olo_map.odm_stripe_unit;
 357         if (layout.olo_map.odm_group_width) {
 358                 objio_seg->group_width = layout.olo_map.odm_group_width;
 359                 objio_seg->group_depth = layout.olo_map.odm_group_depth;
 360                 objio_seg->group_count = layout.olo_map.odm_num_comps /
 361                                                 objio_seg->mirrors_p1 /
 362                                                 objio_seg->group_width;
 363         } else {
 364                 objio_seg->group_width = layout.olo_map.odm_num_comps /
 365                                                 objio_seg->mirrors_p1;
 366                 objio_seg->group_depth = -1;
 367                 objio_seg->group_count = 1;
 368         }
 369
 370         /* Cache this calculation it will hit for every page */
 371         objio_seg->max_io_size = (BIO_MAX_PAGES_KMALLOC * PAGE_SIZE -
 372                                   objio_seg->stripe_unit) *
 373                                  objio_seg->group_width;
 374
 375         *outp = &objio_seg->lseg;
 376         return 0;
 377
 378 err:
 379         kfree(objio_seg);
 380         dprintk("%s: Error: return %d\n", __func__, err);
 381         *outp = NULL;
 382         return err;
 383 }
 384
 385 void objio_free_lseg(struct pnfs_layout_segment *lseg)
 386 {
 387         int i;
 388         struct objio_segment *objio_seg = OBJIO_LSEG(lseg);
 389
 390         for (i = 0; i < objio_seg->num_comps; i++) {
 391                 if (!objio_seg->ods[i])
 392                         break;
 393                 nfs4_put_deviceid_node(&objio_seg->ods[i]->id_node);
 394         }
 395         kfree(objio_seg);
 396 }
 397
 398 int objio_alloc_io_state(struct pnfs_layout_segment *lseg,
 399                          struct objlayout_io_state **outp,
 400                          gfp_t gfp_flags)
 401 {
 402         struct objio_segment *objio_seg = OBJIO_LSEG(lseg);
 403         struct objio_state *ios;
 404         const unsigned first_size = sizeof(*ios) +
 405                                 objio_seg->num_comps * sizeof(ios->per_dev[0]);
 406         const unsigned sec_size = objio_seg->num_comps *
 407                                                 sizeof(ios->ol_state.ioerrs[0]);
 408
 409         ios = kzalloc(first_size + sec_size, gfp_flags);
 410         if (unlikely(!ios))
 411                 return -ENOMEM;
 412
 413         ios->layout = objio_seg;
 414         ios->ol_state.ioerrs = ((void *)ios) + first_size;
 415         ios->ol_state.num_comps = objio_seg->num_comps;
 416
 417         *outp = &ios->ol_state;
 418         return 0;
 419 }
 420
 421 void objio_free_io_state(struct objlayout_io_state *ol_state)
 422 {
 423         struct objio_state *ios = container_of(ol_state, struct objio_state,
 424                                                ol_state);
 425
 426         kfree(ios);
 427 }
 428
 429 enum pnfs_osd_errno osd_pri_2_pnfs_err(enum osd_err_priority oep)
 430 {
 431         switch (oep) {
 432         case OSD_ERR_PRI_NO_ERROR:
 433                 return (enum pnfs_osd_errno)0;
 434
 435         case OSD_ERR_PRI_CLEAR_PAGES:
 436                 BUG_ON(1);
 437                 return 0;
 438
 439         case OSD_ERR_PRI_RESOURCE:
 440                 return PNFS_OSD_ERR_RESOURCE;
 441         case OSD_ERR_PRI_BAD_CRED:
 442                 return PNFS_OSD_ERR_BAD_CRED;
 443         case OSD_ERR_PRI_NO_ACCESS:
 444                 return PNFS_OSD_ERR_NO_ACCESS;
 445         case OSD_ERR_PRI_UNREACHABLE:
 446                 return PNFS_OSD_ERR_UNREACHABLE;
 447         case OSD_ERR_PRI_NOT_FOUND:
 448                 return PNFS_OSD_ERR_NOT_FOUND;
 449         case OSD_ERR_PRI_NO_SPACE:
 450                 return PNFS_OSD_ERR_NO_SPACE;
 451         default:
 452                 WARN_ON(1);
 453                 /* fallthrough */
 454         case OSD_ERR_PRI_EIO:
 455                 return PNFS_OSD_ERR_EIO;
 456         }
 457 }
 458
 459 static void _clear_bio(struct bio *bio)
 460 {
 461         struct bio_vec *bv;
 462         unsigned i;
 463
 464         __bio_for_each_segment(bv, bio, i, 0) {
 465                 unsigned this_count = bv->bv_len;
 466
 467                 if (likely(PAGE_SIZE == this_count))
 468                         clear_highpage(bv->bv_page);
 469                 else
 470                         zero_user(bv->bv_page, bv->bv_offset, this_count);
 471         }
 472 }
 473
 474 static int _io_check(struct objio_state *ios, bool is_write)
 475 {
 476         enum osd_err_priority oep = OSD_ERR_PRI_NO_ERROR;
 477         int lin_ret = 0;
 478         int i;
 479
 480         for (i = 0; i <  ios->numdevs; i++) {
 481                 struct osd_sense_info osi;
 482                 struct osd_request *or = ios->per_dev[i].or;
 483                 unsigned dev;
 484                 int ret;
 485
 486                 if (!or)
 487                         continue;
 488
 489                 ret = osd_req_decode_sense(or, &osi);
 490                 if (likely(!ret))
 491                         continue;
 492
 493                 if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) {
 494                         /* start read offset passed endof file */
 495                         BUG_ON(is_write);
 496                         _clear_bio(ios->per_dev[i].bio);
 497                         dprintk("%s: start read offset passed end of file "
 498                                 "offset=0x%llx, length=0x%lx\n", __func__,
 499                                 _LLU(ios->per_dev[i].offset),
 500                                 ios->per_dev[i].length);
 501
 502                         continue; /* we recovered */
 503                 }
 504                 dev = ios->per_dev[i].dev;
 505                 objlayout_io_set_result(&ios->ol_state, dev,
 506                                         &ios->layout->comps[dev].oc_object_id,
 507                                         osd_pri_2_pnfs_err(osi.osd_err_pri),
 508                                         ios->per_dev[i].offset,
 509                                         ios->per_dev[i].length,
 510                                         is_write);
 511
 512                 if (osi.osd_err_pri >= oep) {
 513                         oep = osi.osd_err_pri;
 514                         lin_ret = ret;
 515                 }
 516         }
 517
 518         return lin_ret;
 519 }
 520
 521 /*
 522  * Common IO state helpers.
 523  */
 524 static void _io_free(struct objio_state *ios)
 525 {
 526         unsigned i;
 527
 528         for (i = 0; i < ios->numdevs; i++) {
 529                 struct _objio_per_comp *per_dev = &ios->per_dev[i];
 530
 531                 if (per_dev->or) {
 532                         osd_end_request(per_dev->or);
 533                         per_dev->or = NULL;
 534                 }
 535
 536                 if (per_dev->bio) {
 537                         bio_put(per_dev->bio);
 538                         per_dev->bio = NULL;
 539                 }
 540         }
 541 }
 542
 543 struct osd_dev *_io_od(struct objio_state *ios, unsigned dev)
 544 {
 545         unsigned min_dev = ios->layout->comps_index;
 546         unsigned max_dev = min_dev + ios->layout->num_comps;
 547
 548         BUG_ON(dev < min_dev || max_dev <= dev);
 549         return ios->layout->ods[dev - min_dev]->od;
 550 }
 551
 552 struct _striping_info {
 553         u64 obj_offset;
 554         u64 group_length;
 555         unsigned dev;
 556         unsigned unit_off;
 557 };
 558
 559 static void _calc_stripe_info(struct objio_state *ios, u64 file_offset,
 560                               struct _striping_info *si)
 561 {
 562         u32     stripe_unit = ios->layout->stripe_unit;
 563         u32     group_width = ios->layout->group_width;
 564         u64     group_depth = ios->layout->group_depth;
 565         u32     U = stripe_unit * group_width;
 566
 567         u64     T = U * group_depth;
 568         u64     S = T * ios->layout->group_count;
 569         u64     M = div64_u64(file_offset, S);
 570
 571         /*
 572         G = (L - (M * S)) / T
 573         H = (L - (M * S)) % T
 574         */
 575         u64     LmodU = file_offset - M * S;
 576         u32     G = div64_u64(LmodU, T);
 577         u64     H = LmodU - G * T;
 578
 579         u32     N = div_u64(H, U);
 580
 581         div_u64_rem(file_offset, stripe_unit, &si->unit_off);
 582         si->obj_offset = si->unit_off + (N * stripe_unit) +
 583                                   (M * group_depth * stripe_unit);
 584
 585         /* "H - (N * U)" is just "H % U" so it's bound to u32 */
 586         si->dev = (u32)(H - (N * U)) / stripe_unit + G * group_width;
 587         si->dev *= ios->layout->mirrors_p1;
 588
 589         si->group_length = T - H;
 590 }
 591
 592 static int _add_stripe_unit(struct objio_state *ios,  unsigned *cur_pg,
 593                 unsigned pgbase, struct _objio_per_comp *per_dev, int cur_len,
 594                 gfp_t gfp_flags)
 595 {
 596         unsigned pg = *cur_pg;
 597         struct request_queue *q =
 598                         osd_request_queue(_io_od(ios, per_dev->dev));
 599
 600         per_dev->length += cur_len;
 601
 602         if (per_dev->bio == NULL) {
 603                 unsigned stripes = ios->layout->num_comps /
 604                                                      ios->layout->mirrors_p1;
 605                 unsigned pages_in_stripe = stripes *
 606                                       (ios->layout->stripe_unit / PAGE_SIZE);
 607                 unsigned bio_size = (ios->ol_state.nr_pages + pages_in_stripe) /
 608                                     stripes;
 609
 610                 if (BIO_MAX_PAGES_KMALLOC < bio_size)
 611                         bio_size = BIO_MAX_PAGES_KMALLOC;
 612
 613                 per_dev->bio = bio_kmalloc(gfp_flags, bio_size);
 614                 if (unlikely(!per_dev->bio)) {
 615                         dprintk("Faild to allocate BIO size=%u\n", bio_size);
 616                         return -ENOMEM;
 617                 }
 618         }
 619
 620         while (cur_len > 0) {
 621                 unsigned pglen = min_t(unsigned, PAGE_SIZE - pgbase, cur_len);
 622                 unsigned added_len;
 623
 624                 BUG_ON(ios->ol_state.nr_pages <= pg);
 625                 cur_len -= pglen;
 626
 627                 added_len = bio_add_pc_page(q, per_dev->bio,
 628                                         ios->ol_state.pages[pg], pglen, pgbase);
 629                 if (unlikely(pglen != added_len))
 630                         return -ENOMEM;
 631                 pgbase = 0;
 632                 ++pg;
 633         }
 634         BUG_ON(cur_len);
 635
 636         *cur_pg = pg;
 637         return 0;
 638 }
 639
 640 static int _prepare_one_group(struct objio_state *ios, u64 length,
 641                               struct _striping_info *si, unsigned *last_pg,
 642                               gfp_t gfp_flags)
 643 {
 644         unsigned stripe_unit = ios->layout->stripe_unit;
 645         unsigned mirrors_p1 = ios->layout->mirrors_p1;
 646         unsigned devs_in_group = ios->layout->group_width * mirrors_p1;
 647         unsigned dev = si->dev;
 648         unsigned first_dev = dev - (dev % devs_in_group);
 649         unsigned max_comp = ios->numdevs ? ios->numdevs - mirrors_p1 : 0;
 650         unsigned cur_pg = *last_pg;
 651         int ret = 0;
 652
 653         while (length) {
 654                 struct _objio_per_comp *per_dev = &ios->per_dev[dev];
 655                 unsigned cur_len, page_off = 0;
 656
 657                 if (!per_dev->length) {
 658                         per_dev->dev = dev;
 659                         if (dev < si->dev) {
 660                                 per_dev->offset = si->obj_offset + stripe_unit -
 661                                                                    si->unit_off;
 662                                 cur_len = stripe_unit;
 663                         } else if (dev == si->dev) {
 664                                 per_dev->offset = si->obj_offset;
 665                                 cur_len = stripe_unit - si->unit_off;
 666                                 page_off = si->unit_off & ~PAGE_MASK;
 667                                 BUG_ON(page_off &&
 668                                       (page_off != ios->ol_state.pgbase));
 669                         } else { /* dev > si->dev */
 670                                 per_dev->offset = si->obj_offset - si->unit_off;
 671                                 cur_len = stripe_unit;
 672                         }
 673
 674                         if (max_comp < dev)
 675                                 max_comp = dev;
 676                 } else {
 677                         cur_len = stripe_unit;
 678                 }
 679                 if (cur_len >= length)
 680                         cur_len = length;
 681
 682                 ret = _add_stripe_unit(ios, &cur_pg, page_off , per_dev,
 683                                        cur_len, gfp_flags);
 684                 if (unlikely(ret))
 685                         goto out;
 686
 687                 dev += mirrors_p1;
 688                 dev = (dev % devs_in_group) + first_dev;
 689
 690                 length -= cur_len;
 691                 ios->length += cur_len;
 692         }
 693 out:
 694         ios->numdevs = max_comp + mirrors_p1;
 695         *last_pg = cur_pg;
 696         return ret;
 697 }
 698
 699 static int _io_rw_pagelist(struct objio_state *ios, gfp_t gfp_flags)
 700 {
 701         u64 length = ios->ol_state.count;
 702         u64 offset = ios->ol_state.offset;
 703         struct _striping_info si;
 704         unsigned last_pg = 0;
 705         int ret = 0;
 706
 707         while (length) {
 708                 _calc_stripe_info(ios, offset, &si);
 709
 710                 if (length < si.group_length)
 711                         si.group_length = length;
 712
 713                 ret = _prepare_one_group(ios, si.group_length, &si, &last_pg, gfp_flags);
 714                 if (unlikely(ret))
 715                         goto out;
 716
 717                 offset += si.group_length;
 718                 length -= si.group_length;
 719         }
 720
 721 out:
 722         if (!ios->length)
 723                 return ret;
 724
 725         return 0;
 726 }
 727
 728 static ssize_t _sync_done(struct objio_state *ios)
 729 {
 730         struct completion *waiting = ios->private;
 731
 732         complete(waiting);
 733         return 0;
 734 }
 735
 736 static void _last_io(struct kref *kref)
 737 {
 738         struct objio_state *ios = container_of(kref, struct objio_state, kref);
 739
 740         ios->done(ios);
 741 }
 742
 743 static void _done_io(struct osd_request *or, void *p)
 744 {
 745         struct objio_state *ios = p;
 746
 747         kref_put(&ios->kref, _last_io);
 748 }
 749
 750 static ssize_t _io_exec(struct objio_state *ios)
 751 {
 752         DECLARE_COMPLETION_ONSTACK(wait);
 753         ssize_t status = 0; /* sync status */
 754         unsigned i;
 755         objio_done_fn saved_done_fn = ios->done;
 756         bool sync = ios->ol_state.sync;
 757
 758         if (sync) {
 759                 ios->done = _sync_done;
 760                 ios->private = &wait;
 761         }
 762
 763         kref_init(&ios->kref);
 764
 765         for (i = 0; i < ios->numdevs; i++) {
 766                 struct osd_request *or = ios->per_dev[i].or;
 767
 768                 if (!or)
 769                         continue;
 770
 771                 kref_get(&ios->kref);
 772                 osd_execute_request_async(or, _done_io, ios);
 773         }
 774
 775         kref_put(&ios->kref, _last_io);
 776
 777         if (sync) {
 778                 wait_for_completion(&wait);
 779                 status = saved_done_fn(ios);
 780         }
 781
 782         return status;
 783 }
 784
 785 /*
 786  * read
 787  */
 788 static ssize_t _read_done(struct objio_state *ios)
 789 {
 790         ssize_t status;
 791         int ret = _io_check(ios, false);
 792
 793         _io_free(ios);
 794
 795         if (likely(!ret))
 796                 status = ios->length;
 797         else
 798                 status = ret;
 799
 800         objlayout_read_done(&ios->ol_state, status, ios->ol_state.sync);
 801         return status;
 802 }
 803
 804 static int _read_mirrors(struct objio_state *ios, unsigned cur_comp)
 805 {
 806         struct osd_request *or = NULL;
 807         struct _objio_per_comp *per_dev = &ios->per_dev[cur_comp];
 808         unsigned dev = per_dev->dev;
 809         struct pnfs_osd_object_cred *cred =
 810                         &ios->layout->comps[dev];
 811         struct osd_obj_id obj = {
 812                 .partition = cred->oc_object_id.oid_partition_id,
 813                 .id = cred->oc_object_id.oid_object_id,
 814         };
 815         int ret;
 816
 817         or = osd_start_request(_io_od(ios, dev), GFP_KERNEL);
 818         if (unlikely(!or)) {
 819                 ret = -ENOMEM;
 820                 goto err;
 821         }
 822         per_dev->or = or;
 823
 824         osd_req_read(or, &obj, per_dev->offset, per_dev->bio, per_dev->length);
 825
 826         ret = osd_finalize_request(or, 0, cred->oc_cap.cred, NULL);
 827         if (ret) {
 828                 dprintk("%s: Faild to osd_finalize_request() => %d\n",
 829                         __func__, ret);
 830                 goto err;
 831         }
 832
 833         dprintk("%s:[%d] dev=%d obj=0x%llx start=0x%llx length=0x%lx\n",
 834                 __func__, cur_comp, dev, obj.id, _LLU(per_dev->offset),
 835                 per_dev->length);
 836
 837 err:
 838         return ret;
 839 }
 840
 841 static ssize_t _read_exec(struct objio_state *ios)
 842 {
 843         unsigned i;
 844         int ret;
 845
 846         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 847                 if (!ios->per_dev[i].length)
 848                         continue;
 849                 ret = _read_mirrors(ios, i);
 850                 if (unlikely(ret))
 851                         goto err;
 852         }
 853
 854         ios->done = _read_done;
 855         return _io_exec(ios); /* In sync mode exec returns the io status */
 856
 857 err:
 858         _io_free(ios);
 859         return ret;
 860 }
 861
 862 ssize_t objio_read_pagelist(struct objlayout_io_state *ol_state)
 863 {
 864         struct objio_state *ios = container_of(ol_state, struct objio_state,
 865                                                ol_state);
 866         int ret;
 867
 868         ret = _io_rw_pagelist(ios, GFP_KERNEL);
 869         if (unlikely(ret))
 870                 return ret;
 871
 872         return _read_exec(ios);
 873 }
 874
 875 /*
 876  * write
 877  */
 878 static ssize_t _write_done(struct objio_state *ios)
 879 {
 880         ssize_t status;
 881         int ret = _io_check(ios, true);
 882
 883         _io_free(ios);
 884
 885         if (likely(!ret)) {
 886                 /* FIXME: should be based on the OSD's persistence model
 887                  * See OSD2r05 Section 4.13 Data persistence model */
 888                 ios->ol_state.committed = NFS_FILE_SYNC;
 889                 status = ios->length;
 890         } else {
 891                 status = ret;
 892         }
 893
 894         objlayout_write_done(&ios->ol_state, status, ios->ol_state.sync);
 895         return status;
 896 }
 897
 898 static int _write_mirrors(struct objio_state *ios, unsigned cur_comp)
 899 {
 900         struct _objio_per_comp *master_dev = &ios->per_dev[cur_comp];
 901         unsigned dev = ios->per_dev[cur_comp].dev;
 902         unsigned last_comp = cur_comp + ios->layout->mirrors_p1;
 903         int ret;
 904
 905         for (; cur_comp < last_comp; ++cur_comp, ++dev) {
 906                 struct osd_request *or = NULL;
 907                 struct pnfs_osd_object_cred *cred =
 908                                         &ios->layout->comps[dev];
 909                 struct osd_obj_id obj = {
 910                         .partition = cred->oc_object_id.oid_partition_id,
 911                         .id = cred->oc_object_id.oid_object_id,
 912                 };
 913                 struct _objio_per_comp *per_dev = &ios->per_dev[cur_comp];
 914                 struct bio *bio;
 915
 916                 or = osd_start_request(_io_od(ios, dev), GFP_NOFS);
 917                 if (unlikely(!or)) {
 918                         ret = -ENOMEM;
 919                         goto err;
 920                 }
 921                 per_dev->or = or;
 922
 923                 if (per_dev != master_dev) {
 924                         bio = bio_kmalloc(GFP_NOFS,
 925                                           master_dev->bio->bi_max_vecs);
 926                         if (unlikely(!bio)) {
 927                                 dprintk("Faild to allocate BIO size=%u\n",
 928                                         master_dev->bio->bi_max_vecs);
 929                                 ret = -ENOMEM;
 930                                 goto err;
 931                         }
 932
 933                         __bio_clone(bio, master_dev->bio);
 934                         bio->bi_bdev = NULL;
 935                         bio->bi_next = NULL;
 936                         per_dev->bio = bio;
 937                         per_dev->dev = dev;
 938                         per_dev->length = master_dev->length;
 939                         per_dev->offset =  master_dev->offset;
 940                 } else {
 941                         bio = master_dev->bio;
 942                         bio->bi_rw |= REQ_WRITE;
 943                 }
 944
 945                 osd_req_write(or, &obj, per_dev->offset, bio, per_dev->length);
 946
 947                 ret = osd_finalize_request(or, 0, cred->oc_cap.cred, NULL);
 948                 if (ret) {
 949                         dprintk("%s: Faild to osd_finalize_request() => %d\n",
 950                                 __func__, ret);
 951                         goto err;
 952                 }
 953
 954                 dprintk("%s:[%d] dev=%d obj=0x%llx start=0x%llx length=0x%lx\n",
 955                         __func__, cur_comp, dev, obj.id, _LLU(per_dev->offset),
 956                         per_dev->length);
 957         }
 958
 959 err:
 960         return ret;
 961 }
 962
 963 static ssize_t _write_exec(struct objio_state *ios)
 964 {
 965         unsigned i;
 966         int ret;
 967
 968         for (i = 0; i < ios->numdevs; i += ios->layout->mirrors_p1) {
 969                 if (!ios->per_dev[i].length)
 970                         continue;
 971                 ret = _write_mirrors(ios, i);
 972                 if (unlikely(ret))
 973                         goto err;
 974         }
 975
 976         ios->done = _write_done;
 977         return _io_exec(ios); /* In sync mode exec returns the io->status */
 978
 979 err:
 980         _io_free(ios);
 981         return ret;
 982 }
 983
 984 ssize_t objio_write_pagelist(struct objlayout_io_state *ol_state, bool stable)
 985 {
 986         struct objio_state *ios = container_of(ol_state, struct objio_state,
 987                                                ol_state);
 988         int ret;
 989
 990         /* TODO: ios->stable = stable; */
 991         ret = _io_rw_pagelist(ios, GFP_NOFS);
 992         if (unlikely(ret))
 993                 return ret;
 994
 995         return _write_exec(ios);
 996 }
 997
 998 static bool objio_pg_test(struct nfs_pageio_descriptor *pgio,
 999                           struct nfs_page *prev, struct nfs_page *req)
1000 {
1001         if (!pnfs_generic_pg_test(pgio, prev, req))
1002                 return false;
1003
1004         return pgio->pg_count + req->wb_bytes <=
1005                         OBJIO_LSEG(pgio->pg_lseg)->max_io_size;
1006 }
1007
1008 static struct pnfs_layoutdriver_type objlayout_type = {
1009         .id = LAYOUT_OSD2_OBJECTS,
1010         .name = "LAYOUT_OSD2_OBJECTS",
1011         .flags                   = PNFS_LAYOUTRET_ON_SETATTR,
1012
1013         .alloc_layout_hdr        = objlayout_alloc_layout_hdr,
1014         .free_layout_hdr         = objlayout_free_layout_hdr,
1015
1016         .alloc_lseg              = objlayout_alloc_lseg,
1017         .free_lseg               = objlayout_free_lseg,
1018
1019         .read_pagelist           = objlayout_read_pagelist,
1020         .write_pagelist          = objlayout_write_pagelist,
1021         .pg_test                 = objio_pg_test,
1022
1023         .free_deviceid_node      = objio_free_deviceid_node,
1024
1025         .encode_layoutcommit     = objlayout_encode_layoutcommit,
1026         .encode_layoutreturn     = objlayout_encode_layoutreturn,
1027 };
1028
1029 MODULE_DESCRIPTION("pNFS Layout Driver for OSD2 objects");
1030 MODULE_AUTHOR("Benny Halevy <bhalevy@panasas.com>");
1031 MODULE_LICENSE("GPL");
1032
1033 static int __init
1034 objlayout_init(void)
1035 {
1036         int ret = pnfs_register_layoutdriver(&objlayout_type);
1037
1038         if (ret)
1039                 printk(KERN_INFO
1040                         "%s: Registering OSD pNFS Layout Driver failed: error=%d\n",
1041                         __func__, ret);
1042         else
1043                 printk(KERN_INFO "%s: Registered OSD pNFS Layout Driver\n",
1044                         __func__);
1045         return ret;
1046 }
1047
1048 static void __exit
1049 objlayout_exit(void)
1050 {
1051         pnfs_unregister_layoutdriver(&objlayout_type);
1052         printk(KERN_INFO "%s: Unregistered OSD pNFS Layout Driver\n",
1053                __func__);
1054 }
1055
1056 module_init(objlayout_init);
1057 module_exit(objlayout_exit);