fs/nfs/nfs4filelayout.c

   1 /*
   2  *  Module for the pnfs nfs4 file layout driver.
   3  *  Defines all I/O and Policy interface operations, plus code
   4  *  to register itself with the pNFS client.
   5  *
   6  *  Copyright (c) 2002
   7  *  The Regents of the University of Michigan
   8  *  All Rights Reserved
   9  *
  10  *  Dean Hildebrand <dhildebz@umich.edu>
  11  *
  12  *  Permission is granted to use, copy, create derivative works, and
  13  *  redistribute this software and such derivative works for any purpose,
  14  *  so long as the name of the University of Michigan is not used in
  15  *  any advertising or publicity pertaining to the use or distribution
  16  *  of this software without specific, written prior authorization. If
  17  *  the above copyright notice or any other identification of the
  18  *  University of Michigan is included in any copy of any portion of
  19  *  this software, then the disclaimer below must also be included.
  20  *
  21  *  This software is provided as is, without representation or warranty
  22  *  of any kind either express or implied, including without limitation
  23  *  the implied warranties of merchantability, fitness for a particular
  24  *  purpose, or noninfringement.  The Regents of the University of
  25  *  Michigan shall not be liable for any damages, including special,
  26  *  indirect, incidental, or consequential damages, with respect to any
  27  *  claim arising out of or in connection with the use of the software,
  28  *  even if it has been or is hereafter advised of the possibility of
  29  *  such damages.
  30  */
  31
  32 #include <linux/nfs_fs.h>
  33 #include <linux/nfs_page.h>
  34 #include <linux/module.h>
  35
  36 #include <linux/sunrpc/metrics.h>
  37
  38 #include "internal.h"
  39 #include "delegation.h"
  40 #include "nfs4filelayout.h"
  41
  42 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  43
  44 MODULE_LICENSE("GPL");
  45 MODULE_AUTHOR("Dean Hildebrand <dhildebz@umich.edu>");
  46 MODULE_DESCRIPTION("The NFSv4 file layout driver");
  47
  48 #define FILELAYOUT_POLL_RETRY_MAX     (15*HZ)
  49
  50 static loff_t
  51 filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
  52                             loff_t offset)
  53 {
  54         u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
  55         u64 stripe_no;
  56         u32 rem;
  57
  58         offset -= flseg->pattern_offset;
  59         stripe_no = div_u64(offset, stripe_width);
  60         div_u64_rem(offset, flseg->stripe_unit, &rem);
  61
  62         return stripe_no * flseg->stripe_unit + rem;
  63 }
  64
  65 /* This function is used by the layout driver to calculate the
  66  * offset of the file on the dserver based on whether the
  67  * layout type is STRIPE_DENSE or STRIPE_SPARSE
  68  */
  69 static loff_t
  70 filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
  71 {
  72         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
  73
  74         switch (flseg->stripe_type) {
  75         case STRIPE_SPARSE:
  76                 return offset;
  77
  78         case STRIPE_DENSE:
  79                 return filelayout_get_dense_offset(flseg, offset);
  80         }
  81
  82         BUG();
  83 }
  84
  85 static void filelayout_reset_write(struct nfs_write_data *data)
  86 {
  87         struct nfs_pgio_header *hdr = data->header;
  88         struct rpc_task *task = &data->task;
  89
  90         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
  91                 dprintk("%s Reset task %5u for i/o through MDS "
  92                         "(req %s/%lld, %u bytes @ offset %llu)\n", __func__,
  93                         data->task.tk_pid,
  94                         hdr->inode->i_sb->s_id,
  95                         (long long)NFS_FILEID(hdr->inode),
  96                         data->args.count,
  97                         (unsigned long long)data->args.offset);
  98
  99                 task->tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
 100                                                         &hdr->pages,
 101                                                         hdr->completion_ops);
 102         }
 103 }
 104
 105 static void filelayout_reset_read(struct nfs_read_data *data)
 106 {
 107         struct nfs_pgio_header *hdr = data->header;
 108         struct rpc_task *task = &data->task;
 109
 110         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 111                 dprintk("%s Reset task %5u for i/o through MDS "
 112                         "(req %s/%lld, %u bytes @ offset %llu)\n", __func__,
 113                         data->task.tk_pid,
 114                         hdr->inode->i_sb->s_id,
 115                         (long long)NFS_FILEID(hdr->inode),
 116                         data->args.count,
 117                         (unsigned long long)data->args.offset);
 118
 119                 task->tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
 120                                                         &hdr->pages,
 121                                                         hdr->completion_ops);
 122         }
 123 }
 124
 125 static int filelayout_async_handle_error(struct rpc_task *task,
 126                                          struct nfs4_state *state,
 127                                          struct nfs_client *clp,
 128                                          struct pnfs_layout_segment *lseg)
 129 {
 130         struct inode *inode = lseg->pls_layout->plh_inode;
 131         struct nfs_server *mds_server = NFS_SERVER(inode);
 132         struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
 133         struct nfs_client *mds_client = mds_server->nfs_client;
 134         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 135
 136         if (task->tk_status >= 0)
 137                 return 0;
 138
 139         switch (task->tk_status) {
 140         /* MDS state errors */
 141         case -NFS4ERR_DELEG_REVOKED:
 142         case -NFS4ERR_ADMIN_REVOKED:
 143         case -NFS4ERR_BAD_STATEID:
 144                 if (state == NULL)
 145                         break;
 146                 nfs_remove_bad_delegation(state->inode);
 147         case -NFS4ERR_OPENMODE:
 148                 if (state == NULL)
 149                         break;
 150                 nfs4_schedule_stateid_recovery(mds_server, state);
 151                 goto wait_on_recovery;
 152         case -NFS4ERR_EXPIRED:
 153                 if (state != NULL)
 154                         nfs4_schedule_stateid_recovery(mds_server, state);
 155                 nfs4_schedule_lease_recovery(mds_client);
 156                 goto wait_on_recovery;
 157         /* DS session errors */
 158         case -NFS4ERR_BADSESSION:
 159         case -NFS4ERR_BADSLOT:
 160         case -NFS4ERR_BAD_HIGH_SLOT:
 161         case -NFS4ERR_DEADSESSION:
 162         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 163         case -NFS4ERR_SEQ_FALSE_RETRY:
 164         case -NFS4ERR_SEQ_MISORDERED:
 165                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 166                         "flags 0x%x\n", __func__, task->tk_status,
 167                         clp->cl_exchange_flags);
 168                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
 169                 break;
 170         case -NFS4ERR_DELAY:
 171         case -NFS4ERR_GRACE:
 172         case -EKEYEXPIRED:
 173                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
 174                 break;
 175         case -NFS4ERR_RETRY_UNCACHED_REP:
 176                 break;
 177         /* Invalidate Layout errors */
 178         case -NFS4ERR_PNFS_NO_LAYOUT:
 179         case -ESTALE:           /* mapped NFS4ERR_STALE */
 180         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
 181         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
 182         case -NFS4ERR_FHEXPIRED:
 183         case -NFS4ERR_WRONG_TYPE:
 184                 dprintk("%s Invalid layout error %d\n", __func__,
 185                         task->tk_status);
 186                 /*
 187                  * Destroy layout so new i/o will get a new layout.
 188                  * Layout will not be destroyed until all current lseg
 189                  * references are put. Mark layout as invalid to resend failed
 190                  * i/o and all i/o waiting on the slot table to the MDS until
 191                  * layout is destroyed and a new valid layout is obtained.
 192                  */
 193                 set_bit(NFS_LAYOUT_INVALID,
 194                                 &NFS_I(inode)->layout->plh_flags);
 195                 pnfs_destroy_layout(NFS_I(inode));
 196                 rpc_wake_up(&tbl->slot_tbl_waitq);
 197                 goto reset;
 198         /* RPC connection errors */
 199         case -ECONNREFUSED:
 200         case -EHOSTDOWN:
 201         case -EHOSTUNREACH:
 202         case -ENETUNREACH:
 203         case -EIO:
 204         case -ETIMEDOUT:
 205         case -EPIPE:
 206                 dprintk("%s DS connection error %d\n", __func__,
 207                         task->tk_status);
 208                 if (!filelayout_test_devid_invalid(devid))
 209                         _pnfs_return_layout(inode);
 210                 filelayout_mark_devid_invalid(devid);
 211                 rpc_wake_up(&tbl->slot_tbl_waitq);
 212                 nfs4_ds_disconnect(clp);
 213                 /* fall through */
 214         default:
 215 reset:
 216                 dprintk("%s Retry through MDS. Error %d\n", __func__,
 217                         task->tk_status);
 218                 return -NFS4ERR_RESET_TO_MDS;
 219         }
 220 out:
 221         task->tk_status = 0;
 222         return -EAGAIN;
 223 wait_on_recovery:
 224         rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
 225         if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
 226                 rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
 227         goto out;
 228 }
 229
 230 /* NFS_PROTO call done callback routines */
 231
 232 static int filelayout_read_done_cb(struct rpc_task *task,
 233                                 struct nfs_read_data *data)
 234 {
 235         struct nfs_pgio_header *hdr = data->header;
 236         int err;
 237
 238         err = filelayout_async_handle_error(task, data->args.context->state,
 239                                             data->ds_clp, hdr->lseg);
 240
 241         switch (err) {
 242         case -NFS4ERR_RESET_TO_MDS:
 243                 filelayout_reset_read(data);
 244                 return task->tk_status;
 245         case -EAGAIN:
 246                 rpc_restart_call_prepare(task);
 247                 return -EAGAIN;
 248         }
 249
 250         return 0;
 251 }
 252
 253 /*
 254  * We reference the rpc_cred of the first WRITE that triggers the need for
 255  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
 256  * rfc5661 is not clear about which credential should be used.
 257  */
 258 static void
 259 filelayout_set_layoutcommit(struct nfs_write_data *wdata)
 260 {
 261         struct nfs_pgio_header *hdr = wdata->header;
 262
 263         if (FILELAYOUT_LSEG(hdr->lseg)->commit_through_mds ||
 264             wdata->res.verf->committed == NFS_FILE_SYNC)
 265                 return;
 266
 267         pnfs_set_layoutcommit(wdata);
 268         dprintk("%s ionde %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
 269                 (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
 270 }
 271
 272 /*
 273  * Call ops for the async read/write cases
 274  * In the case of dense layouts, the offset needs to be reset to its
 275  * original value.
 276  */
 277 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 278 {
 279         struct nfs_read_data *rdata = data;
 280
 281         if (filelayout_reset_to_mds(rdata->header->lseg)) {
 282                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 283                 filelayout_reset_read(rdata);
 284                 rpc_exit(task, 0);
 285                 return;
 286         }
 287         rdata->read_done_cb = filelayout_read_done_cb;
 288
 289         if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
 290                                 &rdata->args.seq_args, &rdata->res.seq_res,
 291                                 task))
 292                 return;
 293
 294         rpc_call_start(task);
 295 }
 296
 297 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 298 {
 299         struct nfs_read_data *rdata = data;
 300
 301         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 302
 303         if (test_bit(NFS_IOHDR_REDO, &rdata->header->flags) &&
 304             task->tk_status == 0)
 305                 return;
 306
 307         /* Note this may cause RPC to be resent */
 308         rdata->header->mds_ops->rpc_call_done(task, data);
 309 }
 310
 311 static void filelayout_read_count_stats(struct rpc_task *task, void *data)
 312 {
 313         struct nfs_read_data *rdata = data;
 314
 315         rpc_count_iostats(task, NFS_SERVER(rdata->header->inode)->client->cl_metrics);
 316 }
 317
 318 static void filelayout_read_release(void *data)
 319 {
 320         struct nfs_read_data *rdata = data;
 321
 322         nfs_put_client(rdata->ds_clp);
 323         rdata->header->mds_ops->rpc_release(data);
 324 }
 325
 326 static int filelayout_write_done_cb(struct rpc_task *task,
 327                                 struct nfs_write_data *data)
 328 {
 329         struct nfs_pgio_header *hdr = data->header;
 330         int err;
 331
 332         err = filelayout_async_handle_error(task, data->args.context->state,
 333                                             data->ds_clp, hdr->lseg);
 334
 335         switch (err) {
 336         case -NFS4ERR_RESET_TO_MDS:
 337                 filelayout_reset_write(data);
 338                 return task->tk_status;
 339         case -EAGAIN:
 340                 rpc_restart_call_prepare(task);
 341                 return -EAGAIN;
 342         }
 343
 344         filelayout_set_layoutcommit(data);
 345         return 0;
 346 }
 347
 348 /* Fake up some data that will cause nfs_commit_release to retry the writes. */
 349 static void prepare_to_resend_writes(struct nfs_commit_data *data)
 350 {
 351         struct nfs_page *first = nfs_list_entry(data->pages.next);
 352
 353         data->task.tk_status = 0;
 354         memcpy(data->verf.verifier, first->wb_verf.verifier,
 355                sizeof(first->wb_verf.verifier));
 356         data->verf.verifier[0]++; /* ensure verifier mismatch */
 357 }
 358
 359 static int filelayout_commit_done_cb(struct rpc_task *task,
 360                                      struct nfs_commit_data *data)
 361 {
 362         int err;
 363
 364         err = filelayout_async_handle_error(task, NULL, data->ds_clp,
 365                                             data->lseg);
 366
 367         switch (err) {
 368         case -NFS4ERR_RESET_TO_MDS:
 369                 prepare_to_resend_writes(data);
 370                 return -EAGAIN;
 371         case -EAGAIN:
 372                 rpc_restart_call_prepare(task);
 373                 return -EAGAIN;
 374         }
 375
 376         return 0;
 377 }
 378
 379 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 380 {
 381         struct nfs_write_data *wdata = data;
 382
 383         if (filelayout_reset_to_mds(wdata->header->lseg)) {
 384                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 385                 filelayout_reset_write(wdata);
 386                 rpc_exit(task, 0);
 387                 return;
 388         }
 389         if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
 390                                 &wdata->args.seq_args, &wdata->res.seq_res,
 391                                 task))
 392                 return;
 393
 394         rpc_call_start(task);
 395 }
 396
 397 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 398 {
 399         struct nfs_write_data *wdata = data;
 400
 401         if (test_bit(NFS_IOHDR_REDO, &wdata->header->flags) &&
 402             task->tk_status == 0)
 403                 return;
 404
 405         /* Note this may cause RPC to be resent */
 406         wdata->header->mds_ops->rpc_call_done(task, data);
 407 }
 408
 409 static void filelayout_write_count_stats(struct rpc_task *task, void *data)
 410 {
 411         struct nfs_write_data *wdata = data;
 412
 413         rpc_count_iostats(task, NFS_SERVER(wdata->header->inode)->client->cl_metrics);
 414 }
 415
 416 static void filelayout_write_release(void *data)
 417 {
 418         struct nfs_write_data *wdata = data;
 419
 420         nfs_put_client(wdata->ds_clp);
 421         wdata->header->mds_ops->rpc_release(data);
 422 }
 423
 424 static void filelayout_commit_prepare(struct rpc_task *task, void *data)
 425 {
 426         struct nfs_commit_data *wdata = data;
 427
 428         if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
 429                                 &wdata->args.seq_args, &wdata->res.seq_res,
 430                                 task))
 431                 return;
 432
 433         rpc_call_start(task);
 434 }
 435
 436 static void filelayout_write_commit_done(struct rpc_task *task, void *data)
 437 {
 438         struct nfs_commit_data *wdata = data;
 439
 440         /* Note this may cause RPC to be resent */
 441         wdata->mds_ops->rpc_call_done(task, data);
 442 }
 443
 444 static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
 445 {
 446         struct nfs_commit_data *cdata = data;
 447
 448         rpc_count_iostats(task, NFS_SERVER(cdata->inode)->client->cl_metrics);
 449 }
 450
 451 static void filelayout_commit_release(void *calldata)
 452 {
 453         struct nfs_commit_data *data = calldata;
 454
 455         data->completion_ops->completion(data);
 456         put_lseg(data->lseg);
 457         nfs_put_client(data->ds_clp);
 458         nfs_commitdata_release(data);
 459 }
 460
 461 static const struct rpc_call_ops filelayout_read_call_ops = {
 462         .rpc_call_prepare = filelayout_read_prepare,
 463         .rpc_call_done = filelayout_read_call_done,
 464         .rpc_count_stats = filelayout_read_count_stats,
 465         .rpc_release = filelayout_read_release,
 466 };
 467
 468 static const struct rpc_call_ops filelayout_write_call_ops = {
 469         .rpc_call_prepare = filelayout_write_prepare,
 470         .rpc_call_done = filelayout_write_call_done,
 471         .rpc_count_stats = filelayout_write_count_stats,
 472         .rpc_release = filelayout_write_release,
 473 };
 474
 475 static const struct rpc_call_ops filelayout_commit_call_ops = {
 476         .rpc_call_prepare = filelayout_commit_prepare,
 477         .rpc_call_done = filelayout_write_commit_done,
 478         .rpc_count_stats = filelayout_commit_count_stats,
 479         .rpc_release = filelayout_commit_release,
 480 };
 481
 482 static enum pnfs_try_status
 483 filelayout_read_pagelist(struct nfs_read_data *data)
 484 {
 485         struct nfs_pgio_header *hdr = data->header;
 486         struct pnfs_layout_segment *lseg = hdr->lseg;
 487         struct nfs4_pnfs_ds *ds;
 488         loff_t offset = data->args.offset;
 489         u32 j, idx;
 490         struct nfs_fh *fh;
 491         int status;
 492
 493         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
 494                 __func__, hdr->inode->i_ino,
 495                 data->args.pgbase, (size_t)data->args.count, offset);
 496
 497         /* Retrieve the correct rpc_client for the byte range */
 498         j = nfs4_fl_calc_j_index(lseg, offset);
 499         idx = nfs4_fl_calc_ds_index(lseg, j);
 500         ds = nfs4_fl_prepare_ds(lseg, idx);
 501         if (!ds)
 502                 return PNFS_NOT_ATTEMPTED;
 503         dprintk("%s USE DS: %s cl_count %d\n", __func__,
 504                 ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 505
 506         /* No multipath support. Use first DS */
 507         atomic_inc(&ds->ds_clp->cl_count);
 508         data->ds_clp = ds->ds_clp;
 509         fh = nfs4_fl_select_ds_fh(lseg, j);
 510         if (fh)
 511                 data->args.fh = fh;
 512
 513         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 514         data->mds_offset = offset;
 515
 516         /* Perform an asynchronous read to ds */
 517         status = nfs_initiate_read(ds->ds_clp->cl_rpcclient, data,
 518                                   &filelayout_read_call_ops, RPC_TASK_SOFTCONN);
 519         BUG_ON(status != 0);
 520         return PNFS_ATTEMPTED;
 521 }
 522
 523 /* Perform async writes. */
 524 static enum pnfs_try_status
 525 filelayout_write_pagelist(struct nfs_write_data *data, int sync)
 526 {
 527         struct nfs_pgio_header *hdr = data->header;
 528         struct pnfs_layout_segment *lseg = hdr->lseg;
 529         struct nfs4_pnfs_ds *ds;
 530         loff_t offset = data->args.offset;
 531         u32 j, idx;
 532         struct nfs_fh *fh;
 533         int status;
 534
 535         /* Retrieve the correct rpc_client for the byte range */
 536         j = nfs4_fl_calc_j_index(lseg, offset);
 537         idx = nfs4_fl_calc_ds_index(lseg, j);
 538         ds = nfs4_fl_prepare_ds(lseg, idx);
 539         if (!ds)
 540                 return PNFS_NOT_ATTEMPTED;
 541         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d\n",
 542                 __func__, hdr->inode->i_ino, sync, (size_t) data->args.count,
 543                 offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 544
 545         data->write_done_cb = filelayout_write_done_cb;
 546         atomic_inc(&ds->ds_clp->cl_count);
 547         data->ds_clp = ds->ds_clp;
 548         fh = nfs4_fl_select_ds_fh(lseg, j);
 549         if (fh)
 550                 data->args.fh = fh;
 551         /*
 552          * Get the file offset on the dserver. Set the write offset to
 553          * this offset and save the original offset.
 554          */
 555         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 556
 557         /* Perform an asynchronous write */
 558         status = nfs_initiate_write(ds->ds_clp->cl_rpcclient, data,
 559                                     &filelayout_write_call_ops, sync,
 560                                     RPC_TASK_SOFTCONN);
 561         BUG_ON(status != 0);
 562         return PNFS_ATTEMPTED;
 563 }
 564
 565 /*
 566  * filelayout_check_layout()
 567  *
 568  * Make sure layout segment parameters are sane WRT the device.
 569  * At this point no generic layer initialization of the lseg has occurred,
 570  * and nothing has been added to the layout_hdr cache.
 571  *
 572  */
 573 static int
 574 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 575                         struct nfs4_filelayout_segment *fl,
 576                         struct nfs4_layoutget_res *lgr,
 577                         struct nfs4_deviceid *id,
 578                         gfp_t gfp_flags)
 579 {
 580         struct nfs4_deviceid_node *d;
 581         struct nfs4_file_layout_dsaddr *dsaddr;
 582         int status = -EINVAL;
 583         struct nfs_server *nfss = NFS_SERVER(lo->plh_inode);
 584
 585         dprintk("--> %s\n", __func__);
 586
 587         /* FIXME: remove this check when layout segment support is added */
 588         if (lgr->range.offset != 0 ||
 589             lgr->range.length != NFS4_MAX_UINT64) {
 590                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 591                         __func__);
 592                 goto out;
 593         }
 594
 595         if (fl->pattern_offset > lgr->range.offset) {
 596                 dprintk("%s pattern_offset %lld too large\n",
 597                                 __func__, fl->pattern_offset);
 598                 goto out;
 599         }
 600
 601         if (!fl->stripe_unit || fl->stripe_unit % PAGE_SIZE) {
 602                 dprintk("%s Invalid stripe unit (%u)\n",
 603                         __func__, fl->stripe_unit);
 604                 goto out;
 605         }
 606
 607         /* find and reference the deviceid */
 608         d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode)->pnfs_curr_ld,
 609                                    NFS_SERVER(lo->plh_inode)->nfs_client, id);
 610         if (d == NULL) {
 611                 dsaddr = get_device_info(lo->plh_inode, id, gfp_flags);
 612                 if (dsaddr == NULL)
 613                         goto out;
 614         } else
 615                 dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 616         /* Found deviceid is being reaped */
 617         if (test_bit(NFS_DEVICEID_INVALID, &dsaddr->id_node.flags))
 618                         goto out_put;
 619
 620         fl->dsaddr = dsaddr;
 621
 622         if (fl->first_stripe_index >= dsaddr->stripe_count) {
 623                 dprintk("%s Bad first_stripe_index %u\n",
 624                                 __func__, fl->first_stripe_index);
 625                 goto out_put;
 626         }
 627
 628         if ((fl->stripe_type == STRIPE_SPARSE &&
 629             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 630             (fl->stripe_type == STRIPE_DENSE &&
 631             fl->num_fh != dsaddr->stripe_count)) {
 632                 dprintk("%s num_fh %u not valid for given packing\n",
 633                         __func__, fl->num_fh);
 634                 goto out_put;
 635         }
 636
 637         if (fl->stripe_unit % nfss->rsize || fl->stripe_unit % nfss->wsize) {
 638                 dprintk("%s Stripe unit (%u) not aligned with rsize %u "
 639                         "wsize %u\n", __func__, fl->stripe_unit, nfss->rsize,
 640                         nfss->wsize);
 641         }
 642
 643         status = 0;
 644 out:
 645         dprintk("--> %s returns %d\n", __func__, status);
 646         return status;
 647 out_put:
 648         nfs4_fl_put_deviceid(dsaddr);
 649         goto out;
 650 }
 651
 652 static void filelayout_free_fh_array(struct nfs4_filelayout_segment *fl)
 653 {
 654         int i;
 655
 656         for (i = 0; i < fl->num_fh; i++) {
 657                 if (!fl->fh_array[i])
 658                         break;
 659                 kfree(fl->fh_array[i]);
 660         }
 661         kfree(fl->fh_array);
 662         fl->fh_array = NULL;
 663 }
 664
 665 static void
 666 _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 667 {
 668         filelayout_free_fh_array(fl);
 669         kfree(fl);
 670 }
 671
 672 static int
 673 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 674                          struct nfs4_filelayout_segment *fl,
 675                          struct nfs4_layoutget_res *lgr,
 676                          struct nfs4_deviceid *id,
 677                          gfp_t gfp_flags)
 678 {
 679         struct xdr_stream stream;
 680         struct xdr_buf buf;
 681         struct page *scratch;
 682         __be32 *p;
 683         uint32_t nfl_util;
 684         int i;
 685
 686         dprintk("%s: set_layout_map Begin\n", __func__);
 687
 688         scratch = alloc_page(gfp_flags);
 689         if (!scratch)
 690                 return -ENOMEM;
 691
 692         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
 693         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 694
 695         /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
 696          * num_fh (4) */
 697         p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
 698         if (unlikely(!p))
 699                 goto out_err;
 700
 701         memcpy(id, p, sizeof(*id));
 702         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 703         nfs4_print_deviceid(id);
 704
 705         nfl_util = be32_to_cpup(p++);
 706         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 707                 fl->commit_through_mds = 1;
 708         if (nfl_util & NFL4_UFLG_DENSE)
 709                 fl->stripe_type = STRIPE_DENSE;
 710         else
 711                 fl->stripe_type = STRIPE_SPARSE;
 712         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 713
 714         fl->first_stripe_index = be32_to_cpup(p++);
 715         p = xdr_decode_hyper(p, &fl->pattern_offset);
 716         fl->num_fh = be32_to_cpup(p++);
 717
 718         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 719                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 720                 fl->pattern_offset);
 721
 722         /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
 723          * Futher checking is done in filelayout_check_layout */
 724         if (fl->num_fh >
 725             max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
 726                 goto out_err;
 727
 728         if (fl->num_fh > 0) {
 729                 fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
 730                                        gfp_flags);
 731                 if (!fl->fh_array)
 732                         goto out_err;
 733         }
 734
 735         for (i = 0; i < fl->num_fh; i++) {
 736                 /* Do we want to use a mempool here? */
 737                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
 738                 if (!fl->fh_array[i])
 739                         goto out_err_free;
 740
 741                 p = xdr_inline_decode(&stream, 4);
 742                 if (unlikely(!p))
 743                         goto out_err_free;
 744                 fl->fh_array[i]->size = be32_to_cpup(p++);
 745                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
 746                         printk(KERN_ERR "NFS: Too big fh %d received %d\n",
 747                                i, fl->fh_array[i]->size);
 748                         goto out_err_free;
 749                 }
 750
 751                 p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
 752                 if (unlikely(!p))
 753                         goto out_err_free;
 754                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 755                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 756                         fl->fh_array[i]->size);
 757         }
 758
 759         __free_page(scratch);
 760         return 0;
 761
 762 out_err_free:
 763         filelayout_free_fh_array(fl);
 764 out_err:
 765         __free_page(scratch);
 766         return -EIO;
 767 }
 768
 769 static void
 770 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 771 {
 772         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 773
 774         dprintk("--> %s\n", __func__);
 775         nfs4_fl_put_deviceid(fl->dsaddr);
 776         /* This assumes a single RW lseg */
 777         if (lseg->pls_range.iomode == IOMODE_RW) {
 778                 struct nfs4_filelayout *flo;
 779
 780                 flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
 781                 flo->commit_info.nbuckets = 0;
 782                 kfree(flo->commit_info.buckets);
 783                 flo->commit_info.buckets = NULL;
 784         }
 785         _filelayout_free_lseg(fl);
 786 }
 787
 788 static int
 789 filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 790                              struct nfs_commit_info *cinfo,
 791                              gfp_t gfp_flags)
 792 {
 793         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 794         struct pnfs_commit_bucket *buckets;
 795         int size;
 796
 797         if (fl->commit_through_mds)
 798                 return 0;
 799         if (cinfo->ds->nbuckets != 0) {
 800                 /* This assumes there is only one IOMODE_RW lseg.  What
 801                  * we really want to do is have a layout_hdr level
 802                  * dictionary of <multipath_list4, fh> keys, each
 803                  * associated with a struct list_head, populated by calls
 804                  * to filelayout_write_pagelist().
 805                  * */
 806                 return 0;
 807         }
 808
 809         size = (fl->stripe_type == STRIPE_SPARSE) ?
 810                 fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
 811
 812         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 813                           gfp_flags);
 814         if (!buckets)
 815                 return -ENOMEM;
 816         else {
 817                 int i;
 818
 819                 spin_lock(cinfo->lock);
 820                 if (cinfo->ds->nbuckets != 0)
 821                         kfree(buckets);
 822                 else {
 823                         cinfo->ds->buckets = buckets;
 824                         cinfo->ds->nbuckets = size;
 825                         for (i = 0; i < size; i++) {
 826                                 INIT_LIST_HEAD(&buckets[i].written);
 827                                 INIT_LIST_HEAD(&buckets[i].committing);
 828                         }
 829                 }
 830                 spin_unlock(cinfo->lock);
 831                 return 0;
 832         }
 833 }
 834
 835 static struct pnfs_layout_segment *
 836 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 837                       struct nfs4_layoutget_res *lgr,
 838                       gfp_t gfp_flags)
 839 {
 840         struct nfs4_filelayout_segment *fl;
 841         int rc;
 842         struct nfs4_deviceid id;
 843
 844         dprintk("--> %s\n", __func__);
 845         fl = kzalloc(sizeof(*fl), gfp_flags);
 846         if (!fl)
 847                 return NULL;
 848
 849         rc = filelayout_decode_layout(layoutid, fl, lgr, &id, gfp_flags);
 850         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id, gfp_flags)) {
 851                 _filelayout_free_lseg(fl);
 852                 return NULL;
 853         }
 854         return &fl->generic_hdr;
 855 }
 856
 857 /*
 858  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 859  *
 860  * return true  : coalesce page
 861  * return false : don't coalesce page
 862  */
 863 static bool
 864 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 865                    struct nfs_page *req)
 866 {
 867         u64 p_stripe, r_stripe;
 868         u32 stripe_unit;
 869
 870         if (!pnfs_generic_pg_test(pgio, prev, req) ||
 871             !nfs_generic_pg_test(pgio, prev, req))
 872                 return false;
 873
 874         p_stripe = (u64)req_offset(prev);
 875         r_stripe = (u64)req_offset(req);
 876         stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 877
 878         do_div(p_stripe, stripe_unit);
 879         do_div(r_stripe, stripe_unit);
 880
 881         return (p_stripe == r_stripe);
 882 }
 883
 884 static void
 885 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 886                         struct nfs_page *req)
 887 {
 888         BUG_ON(pgio->pg_lseg != NULL);
 889
 890         if (req->wb_offset != req->wb_pgbase) {
 891                 /*
 892                  * Handling unaligned pages is difficult, because have to
 893                  * somehow split a req in two in certain cases in the
 894                  * pg.test code.  Avoid this by just not using pnfs
 895                  * in this case.
 896                  */
 897                 nfs_pageio_reset_read_mds(pgio);
 898                 return;
 899         }
 900         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 901                                            req->wb_context,
 902                                            0,
 903                                            NFS4_MAX_UINT64,
 904                                            IOMODE_READ,
 905                                            GFP_KERNEL);
 906         /* If no lseg, fall back to read through mds */
 907         if (pgio->pg_lseg == NULL)
 908                 nfs_pageio_reset_read_mds(pgio);
 909 }
 910
 911 static void
 912 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 913                          struct nfs_page *req)
 914 {
 915         struct nfs_commit_info cinfo;
 916         int status;
 917
 918         BUG_ON(pgio->pg_lseg != NULL);
 919
 920         if (req->wb_offset != req->wb_pgbase)
 921                 goto out_mds;
 922         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 923                                            req->wb_context,
 924                                            0,
 925                                            NFS4_MAX_UINT64,
 926                                            IOMODE_RW,
 927                                            GFP_NOFS);
 928         /* If no lseg, fall back to write through mds */
 929         if (pgio->pg_lseg == NULL)
 930                 goto out_mds;
 931         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 932         status = filelayout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 933         if (status < 0) {
 934                 put_lseg(pgio->pg_lseg);
 935                 pgio->pg_lseg = NULL;
 936                 goto out_mds;
 937         }
 938         return;
 939 out_mds:
 940         nfs_pageio_reset_write_mds(pgio);
 941 }
 942
 943 static const struct nfs_pageio_ops filelayout_pg_read_ops = {
 944         .pg_init = filelayout_pg_init_read,
 945         .pg_test = filelayout_pg_test,
 946         .pg_doio = pnfs_generic_pg_readpages,
 947 };
 948
 949 static const struct nfs_pageio_ops filelayout_pg_write_ops = {
 950         .pg_init = filelayout_pg_init_write,
 951         .pg_test = filelayout_pg_test,
 952         .pg_doio = pnfs_generic_pg_writepages,
 953 };
 954
 955 static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
 956 {
 957         if (fl->stripe_type == STRIPE_SPARSE)
 958                 return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
 959         else
 960                 return j;
 961 }
 962
 963 /* The generic layer is about to remove the req from the commit list.
 964  * If this will make the bucket empty, it will need to put the lseg reference.
 965  */
 966 static void
 967 filelayout_clear_request_commit(struct nfs_page *req,
 968                                 struct nfs_commit_info *cinfo)
 969 {
 970         struct pnfs_layout_segment *freeme = NULL;
 971
 972         spin_lock(cinfo->lock);
 973         if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
 974                 goto out;
 975         cinfo->ds->nwritten--;
 976         if (list_is_singular(&req->wb_list)) {
 977                 struct pnfs_commit_bucket *bucket;
 978
 979                 bucket = list_first_entry(&req->wb_list,
 980                                           struct pnfs_commit_bucket,
 981                                           written);
 982                 freeme = bucket->wlseg;
 983                 bucket->wlseg = NULL;
 984         }
 985 out:
 986         nfs_request_remove_commit_list(req, cinfo);
 987         spin_unlock(cinfo->lock);
 988         put_lseg(freeme);
 989 }
 990
 991 static struct list_head *
 992 filelayout_choose_commit_list(struct nfs_page *req,
 993                               struct pnfs_layout_segment *lseg,
 994                               struct nfs_commit_info *cinfo)
 995 {
 996         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 997         u32 i, j;
 998         struct list_head *list;
 999         struct pnfs_commit_bucket *buckets;
1000
1001         if (fl->commit_through_mds)
1002                 return &cinfo->mds->list;
1003
1004         /* Note that we are calling nfs4_fl_calc_j_index on each page
1005          * that ends up being committed to a data server.  An attractive
1006          * alternative is to add a field to nfs_write_data and nfs_page
1007          * to store the value calculated in filelayout_write_pagelist
1008          * and just use that here.
1009          */
1010         j = nfs4_fl_calc_j_index(lseg, req_offset(req));
1011         i = select_bucket_index(fl, j);
1012         buckets = cinfo->ds->buckets;
1013         list = &buckets[i].written;
1014         if (list_empty(list)) {
1015                 /* Non-empty buckets hold a reference on the lseg.  That ref
1016                  * is normally transferred to the COMMIT call and released
1017                  * there.  It could also be released if the last req is pulled
1018                  * off due to a rewrite, in which case it will be done in
1019                  * filelayout_clear_request_commit
1020                  */
1021                 buckets[i].wlseg = get_lseg(lseg);
1022         }
1023         set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
1024         cinfo->ds->nwritten++;
1025         return list;
1026 }
1027
1028 static void
1029 filelayout_mark_request_commit(struct nfs_page *req,
1030                                struct pnfs_layout_segment *lseg,
1031                                struct nfs_commit_info *cinfo)
1032 {
1033         struct list_head *list;
1034
1035         list = filelayout_choose_commit_list(req, lseg, cinfo);
1036         nfs_request_add_commit_list(req, list, cinfo);
1037 }
1038
1039 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1040 {
1041         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
1042
1043         if (flseg->stripe_type == STRIPE_SPARSE)
1044                 return i;
1045         else
1046                 return nfs4_fl_calc_ds_index(lseg, i);
1047 }
1048
1049 static struct nfs_fh *
1050 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1051 {
1052         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
1053
1054         if (flseg->stripe_type == STRIPE_SPARSE) {
1055                 if (flseg->num_fh == 1)
1056                         i = 0;
1057                 else if (flseg->num_fh == 0)
1058                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
1059                         return NULL;
1060         }
1061         return flseg->fh_array[i];
1062 }
1063
1064 static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
1065 {
1066         struct pnfs_layout_segment *lseg = data->lseg;
1067         struct nfs4_pnfs_ds *ds;
1068         u32 idx;
1069         struct nfs_fh *fh;
1070
1071         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1072         ds = nfs4_fl_prepare_ds(lseg, idx);
1073         if (!ds) {
1074                 prepare_to_resend_writes(data);
1075                 filelayout_commit_release(data);
1076                 return -EAGAIN;
1077         }
1078         dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
1079                 data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count));
1080         data->commit_done_cb = filelayout_commit_done_cb;
1081         atomic_inc(&ds->ds_clp->cl_count);
1082         data->ds_clp = ds->ds_clp;
1083         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1084         if (fh)
1085                 data->args.fh = fh;
1086         return nfs_initiate_commit(ds->ds_clp->cl_rpcclient, data,
1087                                    &filelayout_commit_call_ops, how,
1088                                    RPC_TASK_SOFTCONN);
1089 }
1090
1091 static int
1092 transfer_commit_list(struct list_head *src, struct list_head *dst,
1093                      struct nfs_commit_info *cinfo, int max)
1094 {
1095         struct nfs_page *req, *tmp;
1096         int ret = 0;
1097
1098         list_for_each_entry_safe(req, tmp, src, wb_list) {
1099                 if (!nfs_lock_request(req))
1100                         continue;
1101                 kref_get(&req->wb_kref);
1102                 if (cond_resched_lock(cinfo->lock))
1103                         list_safe_reset_next(req, tmp, wb_list);
1104                 nfs_request_remove_commit_list(req, cinfo);
1105                 clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
1106                 nfs_list_add_request(req, dst);
1107                 ret++;
1108                 if ((ret == max) && !cinfo->dreq)
1109                         break;
1110         }
1111         return ret;
1112 }
1113
1114 static int
1115 filelayout_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
1116                                struct nfs_commit_info *cinfo,
1117                                int max)
1118 {
1119         struct list_head *src = &bucket->written;
1120         struct list_head *dst = &bucket->committing;
1121         int ret;
1122
1123         ret = transfer_commit_list(src, dst, cinfo, max);
1124         if (ret) {
1125                 cinfo->ds->nwritten -= ret;
1126                 cinfo->ds->ncommitting += ret;
1127                 bucket->clseg = bucket->wlseg;
1128                 if (list_empty(src))
1129                         bucket->wlseg = NULL;
1130                 else
1131                         get_lseg(bucket->clseg);
1132         }
1133         return ret;
1134 }
1135
1136 /* Move reqs from written to committing lists, returning count of number moved.
1137  * Note called with cinfo->lock held.
1138  */
1139 static int filelayout_scan_commit_lists(struct nfs_commit_info *cinfo,
1140                                         int max)
1141 {
1142         int i, rv = 0, cnt;
1143
1144         for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
1145                 cnt = filelayout_scan_ds_commit_list(&cinfo->ds->buckets[i],
1146                                                      cinfo, max);
1147                 max -= cnt;
1148                 rv += cnt;
1149         }
1150         return rv;
1151 }
1152
1153 /* Pull everything off the committing lists and dump into @dst */
1154 static void filelayout_recover_commit_reqs(struct list_head *dst,
1155                                            struct nfs_commit_info *cinfo)
1156 {
1157         struct pnfs_commit_bucket *b;
1158         int i;
1159
1160         /* NOTE cinfo->lock is NOT held, relying on fact that this is
1161          * only called on single thread per dreq.
1162          * Can't take the lock because need to do put_lseg
1163          */
1164         for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
1165                 if (transfer_commit_list(&b->written, dst, cinfo, 0)) {
1166                         BUG_ON(!list_empty(&b->written));
1167                         put_lseg(b->wlseg);
1168                         b->wlseg = NULL;
1169                 }
1170         }
1171         cinfo->ds->nwritten = 0;
1172 }
1173
1174 static unsigned int
1175 alloc_ds_commits(struct nfs_commit_info *cinfo, struct list_head *list)
1176 {
1177         struct pnfs_ds_commit_info *fl_cinfo;
1178         struct pnfs_commit_bucket *bucket;
1179         struct nfs_commit_data *data;
1180         int i, j;
1181         unsigned int nreq = 0;
1182
1183         fl_cinfo = cinfo->ds;
1184         bucket = fl_cinfo->buckets;
1185         for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
1186                 if (list_empty(&bucket->committing))
1187                         continue;
1188                 data = nfs_commitdata_alloc();
1189                 if (!data)
1190                         break;
1191                 data->ds_commit_index = i;
1192                 data->lseg = bucket->clseg;
1193                 bucket->clseg = NULL;
1194                 list_add(&data->pages, list);
1195                 nreq++;
1196         }
1197
1198         /* Clean up on error */
1199         for (j = i; j < fl_cinfo->nbuckets; j++, bucket++) {
1200                 if (list_empty(&bucket->committing))
1201                         continue;
1202                 nfs_retry_commit(&bucket->committing, bucket->clseg, cinfo);
1203                 put_lseg(bucket->clseg);
1204                 bucket->clseg = NULL;
1205         }
1206         /* Caller will clean up entries put on list */
1207         return nreq;
1208 }
1209
1210 /* This follows nfs_commit_list pretty closely */
1211 static int
1212 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1213                            int how, struct nfs_commit_info *cinfo)
1214 {
1215         struct nfs_commit_data *data, *tmp;
1216         LIST_HEAD(list);
1217         unsigned int nreq = 0;
1218
1219         if (!list_empty(mds_pages)) {
1220                 data = nfs_commitdata_alloc();
1221                 if (data != NULL) {
1222                         data->lseg = NULL;
1223                         list_add(&data->pages, &list);
1224                         nreq++;
1225                 } else
1226                         nfs_retry_commit(mds_pages, NULL, cinfo);
1227         }
1228
1229         nreq += alloc_ds_commits(cinfo, &list);
1230
1231         if (nreq == 0) {
1232                 cinfo->completion_ops->error_cleanup(NFS_I(inode));
1233                 goto out;
1234         }
1235
1236         atomic_add(nreq, &cinfo->mds->rpcs_out);
1237
1238         list_for_each_entry_safe(data, tmp, &list, pages) {
1239                 list_del_init(&data->pages);
1240                 if (!data->lseg) {
1241                         nfs_init_commit(data, mds_pages, NULL, cinfo);
1242                         nfs_initiate_commit(NFS_CLIENT(inode), data,
1243                                             data->mds_ops, how, 0);
1244                 } else {
1245                         struct pnfs_commit_bucket *buckets;
1246
1247                         buckets = cinfo->ds->buckets;
1248                         nfs_init_commit(data, &buckets[data->ds_commit_index].committing, data->lseg, cinfo);
1249                         filelayout_initiate_commit(data, how);
1250                 }
1251         }
1252 out:
1253         cinfo->ds->ncommitting = 0;
1254         return PNFS_ATTEMPTED;
1255 }
1256
1257 static void
1258 filelayout_free_deveiceid_node(struct nfs4_deviceid_node *d)
1259 {
1260         nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
1261 }
1262
1263 static struct pnfs_layout_hdr *
1264 filelayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
1265 {
1266         struct nfs4_filelayout *flo;
1267
1268         flo = kzalloc(sizeof(*flo), gfp_flags);
1269         return &flo->generic_hdr;
1270 }
1271
1272 static void
1273 filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
1274 {
1275         kfree(FILELAYOUT_FROM_HDR(lo));
1276 }
1277
1278 static struct pnfs_ds_commit_info *
1279 filelayout_get_ds_info(struct inode *inode)
1280 {
1281         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1282
1283         if (layout == NULL)
1284                 return NULL;
1285         else
1286                 return &FILELAYOUT_FROM_HDR(layout)->commit_info;
1287 }
1288
1289 static struct pnfs_layoutdriver_type filelayout_type = {
1290         .id                     = LAYOUT_NFSV4_1_FILES,
1291         .name                   = "LAYOUT_NFSV4_1_FILES",
1292         .owner                  = THIS_MODULE,
1293         .alloc_layout_hdr       = filelayout_alloc_layout_hdr,
1294         .free_layout_hdr        = filelayout_free_layout_hdr,
1295         .alloc_lseg             = filelayout_alloc_lseg,
1296         .free_lseg              = filelayout_free_lseg,
1297         .pg_read_ops            = &filelayout_pg_read_ops,
1298         .pg_write_ops           = &filelayout_pg_write_ops,
1299         .get_ds_info            = &filelayout_get_ds_info,
1300         .mark_request_commit    = filelayout_mark_request_commit,
1301         .clear_request_commit   = filelayout_clear_request_commit,
1302         .scan_commit_lists      = filelayout_scan_commit_lists,
1303         .recover_commit_reqs    = filelayout_recover_commit_reqs,
1304         .commit_pagelist        = filelayout_commit_pagelist,
1305         .read_pagelist          = filelayout_read_pagelist,
1306         .write_pagelist         = filelayout_write_pagelist,
1307         .free_deviceid_node     = filelayout_free_deveiceid_node,
1308 };
1309
1310 static int __init nfs4filelayout_init(void)
1311 {
1312         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
1313                __func__);
1314         return pnfs_register_layoutdriver(&filelayout_type);
1315 }
1316
1317 static void __exit nfs4filelayout_exit(void)
1318 {
1319         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
1320                __func__);
1321         pnfs_unregister_layoutdriver(&filelayout_type);
1322 }
1323
1324 MODULE_ALIAS("nfs-layouttype4-1");
1325
1326 module_init(nfs4filelayout_init);
1327 module_exit(nfs4filelayout_exit);