fs/nfs/objlayout/objlayout.c

   1 /*
   2  *  pNFS Objects layout driver high level definitions
   3  *
   4  *  Copyright (C) 2007 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 <scsi/osd_initiator.h>
  41 #include "objlayout.h"
  42
  43 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  44 /*
  45  * Create a objlayout layout structure for the given inode and return it.
  46  */
  47 struct pnfs_layout_hdr *
  48 objlayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  49 {
  50         struct objlayout *objlay;
  51
  52         objlay = kzalloc(sizeof(struct objlayout), gfp_flags);
  53         if (objlay) {
  54                 spin_lock_init(&objlay->lock);
  55                 INIT_LIST_HEAD(&objlay->err_list);
  56         }
  57         dprintk("%s: Return %p\n", __func__, objlay);
  58         return &objlay->pnfs_layout;
  59 }
  60
  61 /*
  62  * Free an objlayout layout structure
  63  */
  64 void
  65 objlayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  66 {
  67         struct objlayout *objlay = OBJLAYOUT(lo);
  68
  69         dprintk("%s: objlay %p\n", __func__, objlay);
  70
  71         WARN_ON(!list_empty(&objlay->err_list));
  72         kfree(objlay);
  73 }
  74
  75 /*
  76  * Unmarshall layout and store it in pnfslay.
  77  */
  78 struct pnfs_layout_segment *
  79 objlayout_alloc_lseg(struct pnfs_layout_hdr *pnfslay,
  80                      struct nfs4_layoutget_res *lgr,
  81                      gfp_t gfp_flags)
  82 {
  83         int status = -ENOMEM;
  84         struct xdr_stream stream;
  85         struct xdr_buf buf = {
  86                 .pages =  lgr->layoutp->pages,
  87                 .page_len =  lgr->layoutp->len,
  88                 .buflen =  lgr->layoutp->len,
  89                 .len = lgr->layoutp->len,
  90         };
  91         struct page *scratch;
  92         struct pnfs_layout_segment *lseg;
  93
  94         dprintk("%s: Begin pnfslay %p\n", __func__, pnfslay);
  95
  96         scratch = alloc_page(gfp_flags);
  97         if (!scratch)
  98                 goto err_nofree;
  99
 100         xdr_init_decode(&stream, &buf, NULL);
 101         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 102
 103         status = objio_alloc_lseg(&lseg, pnfslay, &lgr->range, &stream, gfp_flags);
 104         if (unlikely(status)) {
 105                 dprintk("%s: objio_alloc_lseg Return err %d\n", __func__,
 106                         status);
 107                 goto err;
 108         }
 109
 110         __free_page(scratch);
 111
 112         dprintk("%s: Return %p\n", __func__, lseg);
 113         return lseg;
 114
 115 err:
 116         __free_page(scratch);
 117 err_nofree:
 118         dprintk("%s: Err Return=>%d\n", __func__, status);
 119         return ERR_PTR(status);
 120 }
 121
 122 /*
 123  * Free a layout segement
 124  */
 125 void
 126 objlayout_free_lseg(struct pnfs_layout_segment *lseg)
 127 {
 128         dprintk("%s: freeing layout segment %p\n", __func__, lseg);
 129
 130         if (unlikely(!lseg))
 131                 return;
 132
 133         objio_free_lseg(lseg);
 134 }
 135
 136 /*
 137  * I/O Operations
 138  */
 139 static inline u64
 140 end_offset(u64 start, u64 len)
 141 {
 142         u64 end;
 143
 144         end = start + len;
 145         return end >= start ? end : NFS4_MAX_UINT64;
 146 }
 147
 148 /* last octet in a range */
 149 static inline u64
 150 last_byte_offset(u64 start, u64 len)
 151 {
 152         u64 end;
 153
 154         BUG_ON(!len);
 155         end = start + len;
 156         return end > start ? end - 1 : NFS4_MAX_UINT64;
 157 }
 158
 159 void _fix_verify_io_params(struct pnfs_layout_segment *lseg,
 160                            struct page ***p_pages, unsigned *p_pgbase,
 161                            u64 offset, unsigned long count)
 162 {
 163         u64 lseg_end_offset;
 164
 165         BUG_ON(offset < lseg->pls_range.offset);
 166         lseg_end_offset = end_offset(lseg->pls_range.offset,
 167                                      lseg->pls_range.length);
 168         BUG_ON(offset >= lseg_end_offset);
 169         WARN_ON(offset + count > lseg_end_offset);
 170
 171         if (*p_pgbase > PAGE_SIZE) {
 172                 dprintk("%s: pgbase(0x%x) > PAGE_SIZE\n", __func__, *p_pgbase);
 173                 *p_pages += *p_pgbase >> PAGE_SHIFT;
 174                 *p_pgbase &= ~PAGE_MASK;
 175         }
 176 }
 177
 178 /*
 179  * I/O done common code
 180  */
 181 static void
 182 objlayout_iodone(struct objlayout_io_res *oir)
 183 {
 184         if (likely(oir->status >= 0)) {
 185                 objio_free_result(oir);
 186         } else {
 187                 struct objlayout *objlay = oir->objlay;
 188
 189                 spin_lock(&objlay->lock);
 190                 objlay->delta_space_valid = OBJ_DSU_INVALID;
 191                 list_add(&objlay->err_list, &oir->err_list);
 192                 spin_unlock(&objlay->lock);
 193         }
 194 }
 195
 196 /*
 197  * objlayout_io_set_result - Set an osd_error code on a specific osd comp.
 198  *
 199  * The @index component IO failed (error returned from target). Register
 200  * the error for later reporting at layout-return.
 201  */
 202 void
 203 objlayout_io_set_result(struct objlayout_io_res *oir, unsigned index,
 204                         struct pnfs_osd_objid *pooid, int osd_error,
 205                         u64 offset, u64 length, bool is_write)
 206 {
 207         struct pnfs_osd_ioerr *ioerr = &oir->ioerrs[index];
 208
 209         BUG_ON(index >= oir->num_comps);
 210         if (osd_error) {
 211                 ioerr->oer_component = *pooid;
 212                 ioerr->oer_comp_offset = offset;
 213                 ioerr->oer_comp_length = length;
 214                 ioerr->oer_iswrite = is_write;
 215                 ioerr->oer_errno = osd_error;
 216
 217                 dprintk("%s: err[%d]: errno=%d is_write=%d dev(%llx:%llx) "
 218                         "par=0x%llx obj=0x%llx offset=0x%llx length=0x%llx\n",
 219                         __func__, index, ioerr->oer_errno,
 220                         ioerr->oer_iswrite,
 221                         _DEVID_LO(&ioerr->oer_component.oid_device_id),
 222                         _DEVID_HI(&ioerr->oer_component.oid_device_id),
 223                         ioerr->oer_component.oid_partition_id,
 224                         ioerr->oer_component.oid_object_id,
 225                         ioerr->oer_comp_offset,
 226                         ioerr->oer_comp_length);
 227         } else {
 228                 /* User need not call if no error is reported */
 229                 ioerr->oer_errno = 0;
 230         }
 231 }
 232
 233 /* Function scheduled on rpc workqueue to call ->nfs_readlist_complete().
 234  * This is because the osd completion is called with ints-off from
 235  * the block layer
 236  */
 237 static void _rpc_read_complete(struct work_struct *work)
 238 {
 239         struct rpc_task *task;
 240         struct nfs_read_data *rdata;
 241
 242         dprintk("%s enter\n", __func__);
 243         task = container_of(work, struct rpc_task, u.tk_work);
 244         rdata = container_of(task, struct nfs_read_data, task);
 245
 246         pnfs_ld_read_done(rdata);
 247 }
 248
 249 void
 250 objlayout_read_done(struct objlayout_io_res *oir, ssize_t status, bool sync)
 251 {
 252         struct nfs_read_data *rdata = oir->rpcdata;
 253
 254         oir->status = rdata->task.tk_status = status;
 255         if (status >= 0)
 256                 rdata->res.count = status;
 257         objlayout_iodone(oir);
 258         /* must not use oir after this point */
 259
 260         dprintk("%s: Return status=%zd eof=%d sync=%d\n", __func__,
 261                 status, rdata->res.eof, sync);
 262
 263         if (sync)
 264                 pnfs_ld_read_done(rdata);
 265         else {
 266                 INIT_WORK(&rdata->task.u.tk_work, _rpc_read_complete);
 267                 schedule_work(&rdata->task.u.tk_work);
 268         }
 269 }
 270
 271 /*
 272  * Perform sync or async reads.
 273  */
 274 enum pnfs_try_status
 275 objlayout_read_pagelist(struct nfs_read_data *rdata)
 276 {
 277         loff_t offset = rdata->args.offset;
 278         size_t count = rdata->args.count;
 279         int err;
 280         loff_t eof;
 281
 282         eof = i_size_read(rdata->inode);
 283         if (unlikely(offset + count > eof)) {
 284                 if (offset >= eof) {
 285                         err = 0;
 286                         rdata->res.count = 0;
 287                         rdata->res.eof = 1;
 288                         /*FIXME: do we need to call pnfs_ld_read_done() */
 289                         goto out;
 290                 }
 291                 count = eof - offset;
 292         }
 293
 294         rdata->res.eof = (offset + count) >= eof;
 295         _fix_verify_io_params(rdata->lseg, &rdata->args.pages,
 296                               &rdata->args.pgbase,
 297                               rdata->args.offset, rdata->args.count);
 298
 299         dprintk("%s: inode(%lx) offset 0x%llx count 0x%Zx eof=%d\n",
 300                 __func__, rdata->inode->i_ino, offset, count, rdata->res.eof);
 301
 302         err = objio_read_pagelist(rdata);
 303  out:
 304         if (unlikely(err)) {
 305                 rdata->pnfs_error = err;
 306                 dprintk("%s: Returned Error %d\n", __func__, err);
 307                 return PNFS_NOT_ATTEMPTED;
 308         }
 309         return PNFS_ATTEMPTED;
 310 }
 311
 312 /* Function scheduled on rpc workqueue to call ->nfs_writelist_complete().
 313  * This is because the osd completion is called with ints-off from
 314  * the block layer
 315  */
 316 static void _rpc_write_complete(struct work_struct *work)
 317 {
 318         struct rpc_task *task;
 319         struct nfs_write_data *wdata;
 320
 321         dprintk("%s enter\n", __func__);
 322         task = container_of(work, struct rpc_task, u.tk_work);
 323         wdata = container_of(task, struct nfs_write_data, task);
 324
 325         pnfs_ld_write_done(wdata);
 326 }
 327
 328 void
 329 objlayout_write_done(struct objlayout_io_res *oir, ssize_t status, bool sync)
 330 {
 331         struct nfs_write_data *wdata = oir->rpcdata;
 332
 333         oir->status = wdata->task.tk_status = status;
 334         if (status >= 0) {
 335                 wdata->res.count = status;
 336                 wdata->verf.committed = oir->committed;
 337         }
 338         objlayout_iodone(oir);
 339         /* must not use oir after this point */
 340
 341         dprintk("%s: Return status %zd committed %d sync=%d\n", __func__,
 342                 status, wdata->verf.committed, sync);
 343
 344         if (sync)
 345                 pnfs_ld_write_done(wdata);
 346         else {
 347                 INIT_WORK(&wdata->task.u.tk_work, _rpc_write_complete);
 348                 schedule_work(&wdata->task.u.tk_work);
 349         }
 350 }
 351
 352 /*
 353  * Perform sync or async writes.
 354  */
 355 enum pnfs_try_status
 356 objlayout_write_pagelist(struct nfs_write_data *wdata,
 357                          int how)
 358 {
 359         int err;
 360
 361         _fix_verify_io_params(wdata->lseg, &wdata->args.pages,
 362                               &wdata->args.pgbase,
 363                               wdata->args.offset, wdata->args.count);
 364
 365         err = objio_write_pagelist(wdata, how);
 366         if (unlikely(err)) {
 367                 wdata->pnfs_error = err;
 368                 dprintk("%s: Returned Error %d\n", __func__, err);
 369                 return PNFS_NOT_ATTEMPTED;
 370         }
 371         return PNFS_ATTEMPTED;
 372 }
 373
 374 void
 375 objlayout_encode_layoutcommit(struct pnfs_layout_hdr *pnfslay,
 376                               struct xdr_stream *xdr,
 377                               const struct nfs4_layoutcommit_args *args)
 378 {
 379         struct objlayout *objlay = OBJLAYOUT(pnfslay);
 380         struct pnfs_osd_layoutupdate lou;
 381         __be32 *start;
 382
 383         dprintk("%s: Begin\n", __func__);
 384
 385         spin_lock(&objlay->lock);
 386         lou.dsu_valid = (objlay->delta_space_valid == OBJ_DSU_VALID);
 387         lou.dsu_delta = objlay->delta_space_used;
 388         objlay->delta_space_used = 0;
 389         objlay->delta_space_valid = OBJ_DSU_INIT;
 390         lou.olu_ioerr_flag = !list_empty(&objlay->err_list);
 391         spin_unlock(&objlay->lock);
 392
 393         start = xdr_reserve_space(xdr, 4);
 394
 395         BUG_ON(pnfs_osd_xdr_encode_layoutupdate(xdr, &lou));
 396
 397         *start = cpu_to_be32((xdr->p - start - 1) * 4);
 398
 399         dprintk("%s: Return delta_space_used %lld err %d\n", __func__,
 400                 lou.dsu_delta, lou.olu_ioerr_flag);
 401 }
 402
 403 static int
 404 err_prio(u32 oer_errno)
 405 {
 406         switch (oer_errno) {
 407         case 0:
 408                 return 0;
 409
 410         case PNFS_OSD_ERR_RESOURCE:
 411                 return OSD_ERR_PRI_RESOURCE;
 412         case PNFS_OSD_ERR_BAD_CRED:
 413                 return OSD_ERR_PRI_BAD_CRED;
 414         case PNFS_OSD_ERR_NO_ACCESS:
 415                 return OSD_ERR_PRI_NO_ACCESS;
 416         case PNFS_OSD_ERR_UNREACHABLE:
 417                 return OSD_ERR_PRI_UNREACHABLE;
 418         case PNFS_OSD_ERR_NOT_FOUND:
 419                 return OSD_ERR_PRI_NOT_FOUND;
 420         case PNFS_OSD_ERR_NO_SPACE:
 421                 return OSD_ERR_PRI_NO_SPACE;
 422         default:
 423                 WARN_ON(1);
 424                 /* fallthrough */
 425         case PNFS_OSD_ERR_EIO:
 426                 return OSD_ERR_PRI_EIO;
 427         }
 428 }
 429
 430 static void
 431 merge_ioerr(struct pnfs_osd_ioerr *dest_err,
 432             const struct pnfs_osd_ioerr *src_err)
 433 {
 434         u64 dest_end, src_end;
 435
 436         if (!dest_err->oer_errno) {
 437                 *dest_err = *src_err;
 438                 /* accumulated device must be blank */
 439                 memset(&dest_err->oer_component.oid_device_id, 0,
 440                         sizeof(dest_err->oer_component.oid_device_id));
 441
 442                 return;
 443         }
 444
 445         if (dest_err->oer_component.oid_partition_id !=
 446                                 src_err->oer_component.oid_partition_id)
 447                 dest_err->oer_component.oid_partition_id = 0;
 448
 449         if (dest_err->oer_component.oid_object_id !=
 450                                 src_err->oer_component.oid_object_id)
 451                 dest_err->oer_component.oid_object_id = 0;
 452
 453         if (dest_err->oer_comp_offset > src_err->oer_comp_offset)
 454                 dest_err->oer_comp_offset = src_err->oer_comp_offset;
 455
 456         dest_end = end_offset(dest_err->oer_comp_offset,
 457                               dest_err->oer_comp_length);
 458         src_end =  end_offset(src_err->oer_comp_offset,
 459                               src_err->oer_comp_length);
 460         if (dest_end < src_end)
 461                 dest_end = src_end;
 462
 463         dest_err->oer_comp_length = dest_end - dest_err->oer_comp_offset;
 464
 465         if ((src_err->oer_iswrite == dest_err->oer_iswrite) &&
 466             (err_prio(src_err->oer_errno) > err_prio(dest_err->oer_errno))) {
 467                         dest_err->oer_errno = src_err->oer_errno;
 468         } else if (src_err->oer_iswrite) {
 469                 dest_err->oer_iswrite = true;
 470                 dest_err->oer_errno = src_err->oer_errno;
 471         }
 472 }
 473
 474 static void
 475 encode_accumulated_error(struct objlayout *objlay, __be32 *p)
 476 {
 477         struct objlayout_io_res *oir, *tmp;
 478         struct pnfs_osd_ioerr accumulated_err = {.oer_errno = 0};
 479
 480         list_for_each_entry_safe(oir, tmp, &objlay->err_list, err_list) {
 481                 unsigned i;
 482
 483                 for (i = 0; i < oir->num_comps; i++) {
 484                         struct pnfs_osd_ioerr *ioerr = &oir->ioerrs[i];
 485
 486                         if (!ioerr->oer_errno)
 487                                 continue;
 488
 489                         printk(KERN_ERR "%s: err[%d]: errno=%d is_write=%d "
 490                                 "dev(%llx:%llx) par=0x%llx obj=0x%llx "
 491                                 "offset=0x%llx length=0x%llx\n",
 492                                 __func__, i, ioerr->oer_errno,
 493                                 ioerr->oer_iswrite,
 494                                 _DEVID_LO(&ioerr->oer_component.oid_device_id),
 495                                 _DEVID_HI(&ioerr->oer_component.oid_device_id),
 496                                 ioerr->oer_component.oid_partition_id,
 497                                 ioerr->oer_component.oid_object_id,
 498                                 ioerr->oer_comp_offset,
 499                                 ioerr->oer_comp_length);
 500
 501                         merge_ioerr(&accumulated_err, ioerr);
 502                 }
 503                 list_del(&oir->err_list);
 504                 objio_free_result(oir);
 505         }
 506
 507         pnfs_osd_xdr_encode_ioerr(p, &accumulated_err);
 508 }
 509
 510 void
 511 objlayout_encode_layoutreturn(struct pnfs_layout_hdr *pnfslay,
 512                               struct xdr_stream *xdr,
 513                               const struct nfs4_layoutreturn_args *args)
 514 {
 515         struct objlayout *objlay = OBJLAYOUT(pnfslay);
 516         struct objlayout_io_res *oir, *tmp;
 517         __be32 *start;
 518
 519         dprintk("%s: Begin\n", __func__);
 520         start = xdr_reserve_space(xdr, 4);
 521         BUG_ON(!start);
 522
 523         spin_lock(&objlay->lock);
 524
 525         list_for_each_entry_safe(oir, tmp, &objlay->err_list, err_list) {
 526                 __be32 *last_xdr = NULL, *p;
 527                 unsigned i;
 528                 int res = 0;
 529
 530                 for (i = 0; i < oir->num_comps; i++) {
 531                         struct pnfs_osd_ioerr *ioerr = &oir->ioerrs[i];
 532
 533                         if (!ioerr->oer_errno)
 534                                 continue;
 535
 536                         dprintk("%s: err[%d]: errno=%d is_write=%d "
 537                                 "dev(%llx:%llx) par=0x%llx obj=0x%llx "
 538                                 "offset=0x%llx length=0x%llx\n",
 539                                 __func__, i, ioerr->oer_errno,
 540                                 ioerr->oer_iswrite,
 541                                 _DEVID_LO(&ioerr->oer_component.oid_device_id),
 542                                 _DEVID_HI(&ioerr->oer_component.oid_device_id),
 543                                 ioerr->oer_component.oid_partition_id,
 544                                 ioerr->oer_component.oid_object_id,
 545                                 ioerr->oer_comp_offset,
 546                                 ioerr->oer_comp_length);
 547
 548                         p = pnfs_osd_xdr_ioerr_reserve_space(xdr);
 549                         if (unlikely(!p)) {
 550                                 res = -E2BIG;
 551                                 break; /* accumulated_error */
 552                         }
 553
 554                         last_xdr = p;
 555                         pnfs_osd_xdr_encode_ioerr(p, &oir->ioerrs[i]);
 556                 }
 557
 558                 /* TODO: use xdr_write_pages */
 559                 if (unlikely(res)) {
 560                         /* no space for even one error descriptor */
 561                         BUG_ON(!last_xdr);
 562
 563                         /* we've encountered a situation with lots and lots of
 564                          * errors and no space to encode them all. Use the last
 565                          * available slot to report the union of all the
 566                          * remaining errors.
 567                          */
 568                         encode_accumulated_error(objlay, last_xdr);
 569                         goto loop_done;
 570                 }
 571                 list_del(&oir->err_list);
 572                 objio_free_result(oir);
 573         }
 574 loop_done:
 575         spin_unlock(&objlay->lock);
 576
 577         *start = cpu_to_be32((xdr->p - start - 1) * 4);
 578         dprintk("%s: Return\n", __func__);
 579 }
 580
 581
 582 /*
 583  * Get Device Info API for io engines
 584  */
 585 struct objlayout_deviceinfo {
 586         struct page *page;
 587         struct pnfs_osd_deviceaddr da; /* This must be last */
 588 };
 589
 590 /* Initialize and call nfs_getdeviceinfo, then decode and return a
 591  * "struct pnfs_osd_deviceaddr *" Eventually objlayout_put_deviceinfo()
 592  * should be called.
 593  */
 594 int objlayout_get_deviceinfo(struct pnfs_layout_hdr *pnfslay,
 595         struct nfs4_deviceid *d_id, struct pnfs_osd_deviceaddr **deviceaddr,
 596         gfp_t gfp_flags)
 597 {
 598         struct objlayout_deviceinfo *odi;
 599         struct pnfs_device pd;
 600         struct super_block *sb;
 601         struct page *page, **pages;
 602         u32 *p;
 603         int err;
 604
 605         page = alloc_page(gfp_flags);
 606         if (!page)
 607                 return -ENOMEM;
 608
 609         pages = &page;
 610         pd.pages = pages;
 611
 612         memcpy(&pd.dev_id, d_id, sizeof(*d_id));
 613         pd.layout_type = LAYOUT_OSD2_OBJECTS;
 614         pd.pages = &page;
 615         pd.pgbase = 0;
 616         pd.pglen = PAGE_SIZE;
 617         pd.mincount = 0;
 618
 619         sb = pnfslay->plh_inode->i_sb;
 620         err = nfs4_proc_getdeviceinfo(NFS_SERVER(pnfslay->plh_inode), &pd);
 621         dprintk("%s nfs_getdeviceinfo returned %d\n", __func__, err);
 622         if (err)
 623                 goto err_out;
 624
 625         p = page_address(page);
 626         odi = kzalloc(sizeof(*odi), gfp_flags);
 627         if (!odi) {
 628                 err = -ENOMEM;
 629                 goto err_out;
 630         }
 631         pnfs_osd_xdr_decode_deviceaddr(&odi->da, p);
 632         odi->page = page;
 633         *deviceaddr = &odi->da;
 634         return 0;
 635
 636 err_out:
 637         __free_page(page);
 638         return err;
 639 }
 640
 641 void objlayout_put_deviceinfo(struct pnfs_osd_deviceaddr *deviceaddr)
 642 {
 643         struct objlayout_deviceinfo *odi = container_of(deviceaddr,
 644                                                 struct objlayout_deviceinfo,
 645                                                 da);
 646
 647         __free_page(odi->page);
 648         kfree(odi);
 649 }