fs/nfs/filelayout/filelayout.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 "../nfs4session.h"
  39 #include "../internal.h"
  40 #include "../delegation.h"
  41 #include "filelayout.h"
  42 #include "../nfs4trace.h"
  43
  44 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  45
  46 MODULE_LICENSE("GPL");
  47 MODULE_AUTHOR("Dean Hildebrand <dhildebz@umich.edu>");
  48 MODULE_DESCRIPTION("The NFSv4 file layout driver");
  49
  50 #define FILELAYOUT_POLL_RETRY_MAX     (15*HZ)
  51
  52 static loff_t
  53 filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
  54                             loff_t offset)
  55 {
  56         u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
  57         u64 stripe_no;
  58         u32 rem;
  59
  60         offset -= flseg->pattern_offset;
  61         stripe_no = div_u64(offset, stripe_width);
  62         div_u64_rem(offset, flseg->stripe_unit, &rem);
  63
  64         return stripe_no * flseg->stripe_unit + rem;
  65 }
  66
  67 /* This function is used by the layout driver to calculate the
  68  * offset of the file on the dserver based on whether the
  69  * layout type is STRIPE_DENSE or STRIPE_SPARSE
  70  */
  71 static loff_t
  72 filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
  73 {
  74         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
  75
  76         switch (flseg->stripe_type) {
  77         case STRIPE_SPARSE:
  78                 return offset;
  79
  80         case STRIPE_DENSE:
  81                 return filelayout_get_dense_offset(flseg, offset);
  82         }
  83
  84         BUG();
  85 }
  86
  87 static void filelayout_reset_write(struct nfs_pgio_data *data)
  88 {
  89         struct nfs_pgio_header *hdr = data->header;
  90         struct rpc_task *task = &data->task;
  91
  92         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
  93                 dprintk("%s Reset task %5u for i/o through MDS "
  94                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
  95                         data->task.tk_pid,
  96                         hdr->inode->i_sb->s_id,
  97                         (unsigned long long)NFS_FILEID(hdr->inode),
  98                         data->args.count,
  99                         (unsigned long long)data->args.offset);
 100
 101                 task->tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
 102                                                         &hdr->pages,
 103                                                         hdr->completion_ops,
 104                                                         hdr->dreq);
 105         }
 106 }
 107
 108 static void filelayout_reset_read(struct nfs_pgio_data *data)
 109 {
 110         struct nfs_pgio_header *hdr = data->header;
 111         struct rpc_task *task = &data->task;
 112
 113         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 114                 dprintk("%s Reset task %5u for i/o through MDS "
 115                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 116                         data->task.tk_pid,
 117                         hdr->inode->i_sb->s_id,
 118                         (unsigned long long)NFS_FILEID(hdr->inode),
 119                         data->args.count,
 120                         (unsigned long long)data->args.offset);
 121
 122                 task->tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
 123                                                         &hdr->pages,
 124                                                         hdr->completion_ops,
 125                                                         hdr->dreq);
 126         }
 127 }
 128
 129 static void filelayout_fenceme(struct inode *inode, struct pnfs_layout_hdr *lo)
 130 {
 131         if (!test_and_clear_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
 132                 return;
 133         pnfs_return_layout(inode);
 134 }
 135
 136 static int filelayout_async_handle_error(struct rpc_task *task,
 137                                          struct nfs4_state *state,
 138                                          struct nfs_client *clp,
 139                                          struct pnfs_layout_segment *lseg)
 140 {
 141         struct pnfs_layout_hdr *lo = lseg->pls_layout;
 142         struct inode *inode = lo->plh_inode;
 143         struct nfs_server *mds_server = NFS_SERVER(inode);
 144         struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
 145         struct nfs_client *mds_client = mds_server->nfs_client;
 146         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 147
 148         if (task->tk_status >= 0)
 149                 return 0;
 150
 151         switch (task->tk_status) {
 152         /* MDS state errors */
 153         case -NFS4ERR_DELEG_REVOKED:
 154         case -NFS4ERR_ADMIN_REVOKED:
 155         case -NFS4ERR_BAD_STATEID:
 156                 if (state == NULL)
 157                         break;
 158                 nfs_remove_bad_delegation(state->inode);
 159         case -NFS4ERR_OPENMODE:
 160                 if (state == NULL)
 161                         break;
 162                 if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 163                         goto out_bad_stateid;
 164                 goto wait_on_recovery;
 165         case -NFS4ERR_EXPIRED:
 166                 if (state != NULL) {
 167                         if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 168                                 goto out_bad_stateid;
 169                 }
 170                 nfs4_schedule_lease_recovery(mds_client);
 171                 goto wait_on_recovery;
 172         /* DS session errors */
 173         case -NFS4ERR_BADSESSION:
 174         case -NFS4ERR_BADSLOT:
 175         case -NFS4ERR_BAD_HIGH_SLOT:
 176         case -NFS4ERR_DEADSESSION:
 177         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 178         case -NFS4ERR_SEQ_FALSE_RETRY:
 179         case -NFS4ERR_SEQ_MISORDERED:
 180                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 181                         "flags 0x%x\n", __func__, task->tk_status,
 182                         clp->cl_exchange_flags);
 183                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
 184                 break;
 185         case -NFS4ERR_DELAY:
 186         case -NFS4ERR_GRACE:
 187                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
 188                 break;
 189         case -NFS4ERR_RETRY_UNCACHED_REP:
 190                 break;
 191         /* Invalidate Layout errors */
 192         case -NFS4ERR_PNFS_NO_LAYOUT:
 193         case -ESTALE:           /* mapped NFS4ERR_STALE */
 194         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
 195         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
 196         case -NFS4ERR_FHEXPIRED:
 197         case -NFS4ERR_WRONG_TYPE:
 198                 dprintk("%s Invalid layout error %d\n", __func__,
 199                         task->tk_status);
 200                 /*
 201                  * Destroy layout so new i/o will get a new layout.
 202                  * Layout will not be destroyed until all current lseg
 203                  * references are put. Mark layout as invalid to resend failed
 204                  * i/o and all i/o waiting on the slot table to the MDS until
 205                  * layout is destroyed and a new valid layout is obtained.
 206                  */
 207                 pnfs_destroy_layout(NFS_I(inode));
 208                 rpc_wake_up(&tbl->slot_tbl_waitq);
 209                 goto reset;
 210         /* RPC connection errors */
 211         case -ECONNREFUSED:
 212         case -EHOSTDOWN:
 213         case -EHOSTUNREACH:
 214         case -ENETUNREACH:
 215         case -EIO:
 216         case -ETIMEDOUT:
 217         case -EPIPE:
 218                 dprintk("%s DS connection error %d\n", __func__,
 219                         task->tk_status);
 220                 nfs4_mark_deviceid_unavailable(devid);
 221                 set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
 222                 rpc_wake_up(&tbl->slot_tbl_waitq);
 223                 /* fall through */
 224         default:
 225 reset:
 226                 dprintk("%s Retry through MDS. Error %d\n", __func__,
 227                         task->tk_status);
 228                 return -NFS4ERR_RESET_TO_MDS;
 229         }
 230 out:
 231         task->tk_status = 0;
 232         return -EAGAIN;
 233 out_bad_stateid:
 234         task->tk_status = -EIO;
 235         return 0;
 236 wait_on_recovery:
 237         rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
 238         if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
 239                 rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
 240         goto out;
 241 }
 242
 243 /* NFS_PROTO call done callback routines */
 244
 245 static int filelayout_read_done_cb(struct rpc_task *task,
 246                                 struct nfs_pgio_data *data)
 247 {
 248         struct nfs_pgio_header *hdr = data->header;
 249         int err;
 250
 251         trace_nfs4_pnfs_read(data, task->tk_status);
 252         err = filelayout_async_handle_error(task, data->args.context->state,
 253                                             data->ds_clp, hdr->lseg);
 254
 255         switch (err) {
 256         case -NFS4ERR_RESET_TO_MDS:
 257                 filelayout_reset_read(data);
 258                 return task->tk_status;
 259         case -EAGAIN:
 260                 rpc_restart_call_prepare(task);
 261                 return -EAGAIN;
 262         }
 263
 264         return 0;
 265 }
 266
 267 /*
 268  * We reference the rpc_cred of the first WRITE that triggers the need for
 269  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
 270  * rfc5661 is not clear about which credential should be used.
 271  */
 272 static void
 273 filelayout_set_layoutcommit(struct nfs_pgio_data *wdata)
 274 {
 275         struct nfs_pgio_header *hdr = wdata->header;
 276
 277         if (FILELAYOUT_LSEG(hdr->lseg)->commit_through_mds ||
 278             wdata->res.verf->committed == NFS_FILE_SYNC)
 279                 return;
 280
 281         pnfs_set_layoutcommit(wdata);
 282         dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
 283                 (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
 284 }
 285
 286 bool
 287 filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node)
 288 {
 289         return filelayout_test_devid_invalid(node) ||
 290                 nfs4_test_deviceid_unavailable(node);
 291 }
 292
 293 static bool
 294 filelayout_reset_to_mds(struct pnfs_layout_segment *lseg)
 295 {
 296         struct nfs4_deviceid_node *node = FILELAYOUT_DEVID_NODE(lseg);
 297
 298         return filelayout_test_devid_unavailable(node);
 299 }
 300
 301 /*
 302  * Call ops for the async read/write cases
 303  * In the case of dense layouts, the offset needs to be reset to its
 304  * original value.
 305  */
 306 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 307 {
 308         struct nfs_pgio_data *rdata = data;
 309
 310         if (unlikely(test_bit(NFS_CONTEXT_BAD, &rdata->args.context->flags))) {
 311                 rpc_exit(task, -EIO);
 312                 return;
 313         }
 314         if (filelayout_reset_to_mds(rdata->header->lseg)) {
 315                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 316                 filelayout_reset_read(rdata);
 317                 rpc_exit(task, 0);
 318                 return;
 319         }
 320         rdata->pgio_done_cb = filelayout_read_done_cb;
 321
 322         if (nfs41_setup_sequence(rdata->ds_clp->cl_session,
 323                         &rdata->args.seq_args,
 324                         &rdata->res.seq_res,
 325                         task))
 326                 return;
 327         if (nfs4_set_rw_stateid(&rdata->args.stateid, rdata->args.context,
 328                         rdata->args.lock_context, FMODE_READ) == -EIO)
 329                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 330 }
 331
 332 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 333 {
 334         struct nfs_pgio_data *rdata = data;
 335
 336         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 337
 338         if (test_bit(NFS_IOHDR_REDO, &rdata->header->flags) &&
 339             task->tk_status == 0) {
 340                 nfs41_sequence_done(task, &rdata->res.seq_res);
 341                 return;
 342         }
 343
 344         /* Note this may cause RPC to be resent */
 345         rdata->header->mds_ops->rpc_call_done(task, data);
 346 }
 347
 348 static void filelayout_read_count_stats(struct rpc_task *task, void *data)
 349 {
 350         struct nfs_pgio_data *rdata = data;
 351
 352         rpc_count_iostats(task, NFS_SERVER(rdata->header->inode)->client->cl_metrics);
 353 }
 354
 355 static void filelayout_read_release(void *data)
 356 {
 357         struct nfs_pgio_data *rdata = data;
 358         struct pnfs_layout_hdr *lo = rdata->header->lseg->pls_layout;
 359
 360         filelayout_fenceme(lo->plh_inode, lo);
 361         nfs_put_client(rdata->ds_clp);
 362         rdata->header->mds_ops->rpc_release(data);
 363 }
 364
 365 static int filelayout_write_done_cb(struct rpc_task *task,
 366                                 struct nfs_pgio_data *data)
 367 {
 368         struct nfs_pgio_header *hdr = data->header;
 369         int err;
 370
 371         trace_nfs4_pnfs_write(data, task->tk_status);
 372         err = filelayout_async_handle_error(task, data->args.context->state,
 373                                             data->ds_clp, hdr->lseg);
 374
 375         switch (err) {
 376         case -NFS4ERR_RESET_TO_MDS:
 377                 filelayout_reset_write(data);
 378                 return task->tk_status;
 379         case -EAGAIN:
 380                 rpc_restart_call_prepare(task);
 381                 return -EAGAIN;
 382         }
 383
 384         filelayout_set_layoutcommit(data);
 385         return 0;
 386 }
 387
 388 /* Fake up some data that will cause nfs_commit_release to retry the writes. */
 389 static void prepare_to_resend_writes(struct nfs_commit_data *data)
 390 {
 391         struct nfs_page *first = nfs_list_entry(data->pages.next);
 392
 393         data->task.tk_status = 0;
 394         memcpy(&data->verf.verifier, &first->wb_verf,
 395                sizeof(data->verf.verifier));
 396         data->verf.verifier.data[0]++; /* ensure verifier mismatch */
 397 }
 398
 399 static int filelayout_commit_done_cb(struct rpc_task *task,
 400                                      struct nfs_commit_data *data)
 401 {
 402         int err;
 403
 404         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
 405         err = filelayout_async_handle_error(task, NULL, data->ds_clp,
 406                                             data->lseg);
 407
 408         switch (err) {
 409         case -NFS4ERR_RESET_TO_MDS:
 410                 prepare_to_resend_writes(data);
 411                 return -EAGAIN;
 412         case -EAGAIN:
 413                 rpc_restart_call_prepare(task);
 414                 return -EAGAIN;
 415         }
 416
 417         return 0;
 418 }
 419
 420 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 421 {
 422         struct nfs_pgio_data *wdata = data;
 423
 424         if (unlikely(test_bit(NFS_CONTEXT_BAD, &wdata->args.context->flags))) {
 425                 rpc_exit(task, -EIO);
 426                 return;
 427         }
 428         if (filelayout_reset_to_mds(wdata->header->lseg)) {
 429                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 430                 filelayout_reset_write(wdata);
 431                 rpc_exit(task, 0);
 432                 return;
 433         }
 434         if (nfs41_setup_sequence(wdata->ds_clp->cl_session,
 435                         &wdata->args.seq_args,
 436                         &wdata->res.seq_res,
 437                         task))
 438                 return;
 439         if (nfs4_set_rw_stateid(&wdata->args.stateid, wdata->args.context,
 440                         wdata->args.lock_context, FMODE_WRITE) == -EIO)
 441                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 442 }
 443
 444 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 445 {
 446         struct nfs_pgio_data *wdata = data;
 447
 448         if (test_bit(NFS_IOHDR_REDO, &wdata->header->flags) &&
 449             task->tk_status == 0) {
 450                 nfs41_sequence_done(task, &wdata->res.seq_res);
 451                 return;
 452         }
 453
 454         /* Note this may cause RPC to be resent */
 455         wdata->header->mds_ops->rpc_call_done(task, data);
 456 }
 457
 458 static void filelayout_write_count_stats(struct rpc_task *task, void *data)
 459 {
 460         struct nfs_pgio_data *wdata = data;
 461
 462         rpc_count_iostats(task, NFS_SERVER(wdata->header->inode)->client->cl_metrics);
 463 }
 464
 465 static void filelayout_write_release(void *data)
 466 {
 467         struct nfs_pgio_data *wdata = data;
 468         struct pnfs_layout_hdr *lo = wdata->header->lseg->pls_layout;
 469
 470         filelayout_fenceme(lo->plh_inode, lo);
 471         nfs_put_client(wdata->ds_clp);
 472         wdata->header->mds_ops->rpc_release(data);
 473 }
 474
 475 static void filelayout_commit_prepare(struct rpc_task *task, void *data)
 476 {
 477         struct nfs_commit_data *wdata = data;
 478
 479         nfs41_setup_sequence(wdata->ds_clp->cl_session,
 480                         &wdata->args.seq_args,
 481                         &wdata->res.seq_res,
 482                         task);
 483 }
 484
 485 static void filelayout_write_commit_done(struct rpc_task *task, void *data)
 486 {
 487         struct nfs_commit_data *wdata = data;
 488
 489         /* Note this may cause RPC to be resent */
 490         wdata->mds_ops->rpc_call_done(task, data);
 491 }
 492
 493 static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
 494 {
 495         struct nfs_commit_data *cdata = data;
 496
 497         rpc_count_iostats(task, NFS_SERVER(cdata->inode)->client->cl_metrics);
 498 }
 499
 500 static void filelayout_commit_release(void *calldata)
 501 {
 502         struct nfs_commit_data *data = calldata;
 503
 504         data->completion_ops->completion(data);
 505         pnfs_put_lseg(data->lseg);
 506         nfs_put_client(data->ds_clp);
 507         nfs_commitdata_release(data);
 508 }
 509
 510 static const struct rpc_call_ops filelayout_read_call_ops = {
 511         .rpc_call_prepare = filelayout_read_prepare,
 512         .rpc_call_done = filelayout_read_call_done,
 513         .rpc_count_stats = filelayout_read_count_stats,
 514         .rpc_release = filelayout_read_release,
 515 };
 516
 517 static const struct rpc_call_ops filelayout_write_call_ops = {
 518         .rpc_call_prepare = filelayout_write_prepare,
 519         .rpc_call_done = filelayout_write_call_done,
 520         .rpc_count_stats = filelayout_write_count_stats,
 521         .rpc_release = filelayout_write_release,
 522 };
 523
 524 static const struct rpc_call_ops filelayout_commit_call_ops = {
 525         .rpc_call_prepare = filelayout_commit_prepare,
 526         .rpc_call_done = filelayout_write_commit_done,
 527         .rpc_count_stats = filelayout_commit_count_stats,
 528         .rpc_release = filelayout_commit_release,
 529 };
 530
 531 static enum pnfs_try_status
 532 filelayout_read_pagelist(struct nfs_pgio_data *data)
 533 {
 534         struct nfs_pgio_header *hdr = data->header;
 535         struct pnfs_layout_segment *lseg = hdr->lseg;
 536         struct nfs4_pnfs_ds *ds;
 537         struct rpc_clnt *ds_clnt;
 538         loff_t offset = data->args.offset;
 539         u32 j, idx;
 540         struct nfs_fh *fh;
 541
 542         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
 543                 __func__, hdr->inode->i_ino,
 544                 data->args.pgbase, (size_t)data->args.count, offset);
 545
 546         /* Retrieve the correct rpc_client for the byte range */
 547         j = nfs4_fl_calc_j_index(lseg, offset);
 548         idx = nfs4_fl_calc_ds_index(lseg, j);
 549         ds = nfs4_fl_prepare_ds(lseg, idx);
 550         if (!ds)
 551                 return PNFS_NOT_ATTEMPTED;
 552
 553         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 554         if (IS_ERR(ds_clnt))
 555                 return PNFS_NOT_ATTEMPTED;
 556
 557         dprintk("%s USE DS: %s cl_count %d\n", __func__,
 558                 ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 559
 560         /* No multipath support. Use first DS */
 561         atomic_inc(&ds->ds_clp->cl_count);
 562         data->ds_clp = ds->ds_clp;
 563         data->ds_idx = idx;
 564         fh = nfs4_fl_select_ds_fh(lseg, j);
 565         if (fh)
 566                 data->args.fh = fh;
 567
 568         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 569         data->mds_offset = offset;
 570
 571         /* Perform an asynchronous read to ds */
 572         nfs_initiate_pgio(ds_clnt, data,
 573                             &filelayout_read_call_ops, 0, RPC_TASK_SOFTCONN);
 574         return PNFS_ATTEMPTED;
 575 }
 576
 577 /* Perform async writes. */
 578 static enum pnfs_try_status
 579 filelayout_write_pagelist(struct nfs_pgio_data *data, int sync)
 580 {
 581         struct nfs_pgio_header *hdr = data->header;
 582         struct pnfs_layout_segment *lseg = hdr->lseg;
 583         struct nfs4_pnfs_ds *ds;
 584         struct rpc_clnt *ds_clnt;
 585         loff_t offset = data->args.offset;
 586         u32 j, idx;
 587         struct nfs_fh *fh;
 588
 589         /* Retrieve the correct rpc_client for the byte range */
 590         j = nfs4_fl_calc_j_index(lseg, offset);
 591         idx = nfs4_fl_calc_ds_index(lseg, j);
 592         ds = nfs4_fl_prepare_ds(lseg, idx);
 593         if (!ds)
 594                 return PNFS_NOT_ATTEMPTED;
 595
 596         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 597         if (IS_ERR(ds_clnt))
 598                 return PNFS_NOT_ATTEMPTED;
 599
 600         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d\n",
 601                 __func__, hdr->inode->i_ino, sync, (size_t) data->args.count,
 602                 offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 603
 604         data->pgio_done_cb = filelayout_write_done_cb;
 605         atomic_inc(&ds->ds_clp->cl_count);
 606         data->ds_clp = ds->ds_clp;
 607         data->ds_idx = idx;
 608         fh = nfs4_fl_select_ds_fh(lseg, j);
 609         if (fh)
 610                 data->args.fh = fh;
 611
 612         data->args.offset = filelayout_get_dserver_offset(lseg, offset);
 613
 614         /* Perform an asynchronous write */
 615         nfs_initiate_pgio(ds_clnt, data,
 616                                     &filelayout_write_call_ops, sync,
 617                                     RPC_TASK_SOFTCONN);
 618         return PNFS_ATTEMPTED;
 619 }
 620
 621 /*
 622  * filelayout_check_layout()
 623  *
 624  * Make sure layout segment parameters are sane WRT the device.
 625  * At this point no generic layer initialization of the lseg has occurred,
 626  * and nothing has been added to the layout_hdr cache.
 627  *
 628  */
 629 static int
 630 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 631                         struct nfs4_filelayout_segment *fl,
 632                         struct nfs4_layoutget_res *lgr,
 633                         struct nfs4_deviceid *id,
 634                         gfp_t gfp_flags)
 635 {
 636         struct nfs4_deviceid_node *d;
 637         struct nfs4_file_layout_dsaddr *dsaddr;
 638         int status = -EINVAL;
 639
 640         dprintk("--> %s\n", __func__);
 641
 642         /* FIXME: remove this check when layout segment support is added */
 643         if (lgr->range.offset != 0 ||
 644             lgr->range.length != NFS4_MAX_UINT64) {
 645                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 646                         __func__);
 647                 goto out;
 648         }
 649
 650         if (fl->pattern_offset > lgr->range.offset) {
 651                 dprintk("%s pattern_offset %lld too large\n",
 652                                 __func__, fl->pattern_offset);
 653                 goto out;
 654         }
 655
 656         if (!fl->stripe_unit) {
 657                 dprintk("%s Invalid stripe unit (%u)\n",
 658                         __func__, fl->stripe_unit);
 659                 goto out;
 660         }
 661
 662         /* find and reference the deviceid */
 663         d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode)->pnfs_curr_ld,
 664                                    NFS_SERVER(lo->plh_inode)->nfs_client, id);
 665         if (d == NULL) {
 666                 dsaddr = filelayout_get_device_info(lo->plh_inode, id,
 667                                 lo->plh_lc_cred, gfp_flags);
 668                 if (dsaddr == NULL)
 669                         goto out;
 670         } else
 671                 dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 672         /* Found deviceid is unavailable */
 673         if (filelayout_test_devid_unavailable(&dsaddr->id_node))
 674                         goto out_put;
 675
 676         fl->dsaddr = dsaddr;
 677
 678         if (fl->first_stripe_index >= dsaddr->stripe_count) {
 679                 dprintk("%s Bad first_stripe_index %u\n",
 680                                 __func__, fl->first_stripe_index);
 681                 goto out_put;
 682         }
 683
 684         if ((fl->stripe_type == STRIPE_SPARSE &&
 685             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 686             (fl->stripe_type == STRIPE_DENSE &&
 687             fl->num_fh != dsaddr->stripe_count)) {
 688                 dprintk("%s num_fh %u not valid for given packing\n",
 689                         __func__, fl->num_fh);
 690                 goto out_put;
 691         }
 692
 693         status = 0;
 694 out:
 695         dprintk("--> %s returns %d\n", __func__, status);
 696         return status;
 697 out_put:
 698         nfs4_fl_put_deviceid(dsaddr);
 699         goto out;
 700 }
 701
 702 static void filelayout_free_fh_array(struct nfs4_filelayout_segment *fl)
 703 {
 704         int i;
 705
 706         for (i = 0; i < fl->num_fh; i++) {
 707                 if (!fl->fh_array[i])
 708                         break;
 709                 kfree(fl->fh_array[i]);
 710         }
 711         kfree(fl->fh_array);
 712         fl->fh_array = NULL;
 713 }
 714
 715 static void
 716 _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 717 {
 718         filelayout_free_fh_array(fl);
 719         kfree(fl);
 720 }
 721
 722 static int
 723 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 724                          struct nfs4_filelayout_segment *fl,
 725                          struct nfs4_layoutget_res *lgr,
 726                          struct nfs4_deviceid *id,
 727                          gfp_t gfp_flags)
 728 {
 729         struct xdr_stream stream;
 730         struct xdr_buf buf;
 731         struct page *scratch;
 732         __be32 *p;
 733         uint32_t nfl_util;
 734         int i;
 735
 736         dprintk("%s: set_layout_map Begin\n", __func__);
 737
 738         scratch = alloc_page(gfp_flags);
 739         if (!scratch)
 740                 return -ENOMEM;
 741
 742         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
 743         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 744
 745         /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
 746          * num_fh (4) */
 747         p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
 748         if (unlikely(!p))
 749                 goto out_err;
 750
 751         memcpy(id, p, sizeof(*id));
 752         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 753         nfs4_print_deviceid(id);
 754
 755         nfl_util = be32_to_cpup(p++);
 756         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 757                 fl->commit_through_mds = 1;
 758         if (nfl_util & NFL4_UFLG_DENSE)
 759                 fl->stripe_type = STRIPE_DENSE;
 760         else
 761                 fl->stripe_type = STRIPE_SPARSE;
 762         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 763
 764         fl->first_stripe_index = be32_to_cpup(p++);
 765         p = xdr_decode_hyper(p, &fl->pattern_offset);
 766         fl->num_fh = be32_to_cpup(p++);
 767
 768         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 769                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 770                 fl->pattern_offset);
 771
 772         /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
 773          * Futher checking is done in filelayout_check_layout */
 774         if (fl->num_fh >
 775             max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
 776                 goto out_err;
 777
 778         if (fl->num_fh > 0) {
 779                 fl->fh_array = kcalloc(fl->num_fh, sizeof(fl->fh_array[0]),
 780                                        gfp_flags);
 781                 if (!fl->fh_array)
 782                         goto out_err;
 783         }
 784
 785         for (i = 0; i < fl->num_fh; i++) {
 786                 /* Do we want to use a mempool here? */
 787                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
 788                 if (!fl->fh_array[i])
 789                         goto out_err_free;
 790
 791                 p = xdr_inline_decode(&stream, 4);
 792                 if (unlikely(!p))
 793                         goto out_err_free;
 794                 fl->fh_array[i]->size = be32_to_cpup(p++);
 795                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
 796                         printk(KERN_ERR "NFS: Too big fh %d received %d\n",
 797                                i, fl->fh_array[i]->size);
 798                         goto out_err_free;
 799                 }
 800
 801                 p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
 802                 if (unlikely(!p))
 803                         goto out_err_free;
 804                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 805                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 806                         fl->fh_array[i]->size);
 807         }
 808
 809         __free_page(scratch);
 810         return 0;
 811
 812 out_err_free:
 813         filelayout_free_fh_array(fl);
 814 out_err:
 815         __free_page(scratch);
 816         return -EIO;
 817 }
 818
 819 static void
 820 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 821 {
 822         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 823
 824         dprintk("--> %s\n", __func__);
 825         nfs4_fl_put_deviceid(fl->dsaddr);
 826         /* This assumes a single RW lseg */
 827         if (lseg->pls_range.iomode == IOMODE_RW) {
 828                 struct nfs4_filelayout *flo;
 829
 830                 flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
 831                 flo->commit_info.nbuckets = 0;
 832                 kfree(flo->commit_info.buckets);
 833                 flo->commit_info.buckets = NULL;
 834         }
 835         _filelayout_free_lseg(fl);
 836 }
 837
 838 static int
 839 filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 840                              struct nfs_commit_info *cinfo,
 841                              gfp_t gfp_flags)
 842 {
 843         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 844         struct pnfs_commit_bucket *buckets;
 845         int size, i;
 846
 847         if (fl->commit_through_mds)
 848                 return 0;
 849
 850         size = (fl->stripe_type == STRIPE_SPARSE) ?
 851                 fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
 852
 853         if (cinfo->ds->nbuckets >= size) {
 854                 /* This assumes there is only one IOMODE_RW lseg.  What
 855                  * we really want to do is have a layout_hdr level
 856                  * dictionary of <multipath_list4, fh> keys, each
 857                  * associated with a struct list_head, populated by calls
 858                  * to filelayout_write_pagelist().
 859                  * */
 860                 return 0;
 861         }
 862
 863         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 864                           gfp_flags);
 865         if (!buckets)
 866                 return -ENOMEM;
 867         for (i = 0; i < size; i++) {
 868                 INIT_LIST_HEAD(&buckets[i].written);
 869                 INIT_LIST_HEAD(&buckets[i].committing);
 870                 /* mark direct verifier as unset */
 871                 buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW;
 872         }
 873
 874         spin_lock(cinfo->lock);
 875         if (cinfo->ds->nbuckets >= size)
 876                 goto out;
 877         for (i = 0; i < cinfo->ds->nbuckets; i++) {
 878                 list_splice(&cinfo->ds->buckets[i].written,
 879                             &buckets[i].written);
 880                 list_splice(&cinfo->ds->buckets[i].committing,
 881                             &buckets[i].committing);
 882                 buckets[i].direct_verf.committed =
 883                         cinfo->ds->buckets[i].direct_verf.committed;
 884                 buckets[i].wlseg = cinfo->ds->buckets[i].wlseg;
 885                 buckets[i].clseg = cinfo->ds->buckets[i].clseg;
 886         }
 887         swap(cinfo->ds->buckets, buckets);
 888         cinfo->ds->nbuckets = size;
 889 out:
 890         spin_unlock(cinfo->lock);
 891         kfree(buckets);
 892         return 0;
 893 }
 894
 895 static struct pnfs_layout_segment *
 896 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 897                       struct nfs4_layoutget_res *lgr,
 898                       gfp_t gfp_flags)
 899 {
 900         struct nfs4_filelayout_segment *fl;
 901         int rc;
 902         struct nfs4_deviceid id;
 903
 904         dprintk("--> %s\n", __func__);
 905         fl = kzalloc(sizeof(*fl), gfp_flags);
 906         if (!fl)
 907                 return NULL;
 908
 909         rc = filelayout_decode_layout(layoutid, fl, lgr, &id, gfp_flags);
 910         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id, gfp_flags)) {
 911                 _filelayout_free_lseg(fl);
 912                 return NULL;
 913         }
 914         return &fl->generic_hdr;
 915 }
 916
 917 /*
 918  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 919  *
 920  * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
 921  * of bytes (maximum @req->wb_bytes) that can be coalesced.
 922  */
 923 static size_t
 924 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 925                    struct nfs_page *req)
 926 {
 927         unsigned int size;
 928         u64 p_stripe, r_stripe;
 929         u32 stripe_offset;
 930         u64 segment_offset = pgio->pg_lseg->pls_range.offset;
 931         u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 932
 933         /* calls nfs_generic_pg_test */
 934         size = pnfs_generic_pg_test(pgio, prev, req);
 935         if (!size)
 936                 return 0;
 937
 938         /* see if req and prev are in the same stripe */
 939         if (prev) {
 940                 p_stripe = (u64)req_offset(prev) - segment_offset;
 941                 r_stripe = (u64)req_offset(req) - segment_offset;
 942                 do_div(p_stripe, stripe_unit);
 943                 do_div(r_stripe, stripe_unit);
 944
 945                 if (p_stripe != r_stripe)
 946                         return 0;
 947         }
 948
 949         /* calculate remaining bytes in the current stripe */
 950         div_u64_rem((u64)req_offset(req) - segment_offset,
 951                         stripe_unit,
 952                         &stripe_offset);
 953         WARN_ON_ONCE(stripe_offset > stripe_unit);
 954         if (stripe_offset >= stripe_unit)
 955                 return 0;
 956         return min(stripe_unit - (unsigned int)stripe_offset, size);
 957 }
 958
 959 static void
 960 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 961                         struct nfs_page *req)
 962 {
 963         if (!pgio->pg_lseg)
 964                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 965                                            req->wb_context,
 966                                            0,
 967                                            NFS4_MAX_UINT64,
 968                                            IOMODE_READ,
 969                                            GFP_KERNEL);
 970         /* If no lseg, fall back to read through mds */
 971         if (pgio->pg_lseg == NULL)
 972                 nfs_pageio_reset_read_mds(pgio);
 973 }
 974
 975 static void
 976 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 977                          struct nfs_page *req)
 978 {
 979         struct nfs_commit_info cinfo;
 980         int status;
 981
 982         if (!pgio->pg_lseg)
 983                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 984                                            req->wb_context,
 985                                            0,
 986                                            NFS4_MAX_UINT64,
 987                                            IOMODE_RW,
 988                                            GFP_NOFS);
 989         /* If no lseg, fall back to write through mds */
 990         if (pgio->pg_lseg == NULL)
 991                 goto out_mds;
 992         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 993         status = filelayout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 994         if (status < 0) {
 995                 pnfs_put_lseg(pgio->pg_lseg);
 996                 pgio->pg_lseg = NULL;
 997                 goto out_mds;
 998         }
 999         return;
1000 out_mds:
1001         nfs_pageio_reset_write_mds(pgio);
1002 }
1003
1004 static const struct nfs_pageio_ops filelayout_pg_read_ops = {
1005         .pg_init = filelayout_pg_init_read,
1006         .pg_test = filelayout_pg_test,
1007         .pg_doio = pnfs_generic_pg_readpages,
1008 };
1009
1010 static const struct nfs_pageio_ops filelayout_pg_write_ops = {
1011         .pg_init = filelayout_pg_init_write,
1012         .pg_test = filelayout_pg_test,
1013         .pg_doio = pnfs_generic_pg_writepages,
1014 };
1015
1016 static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
1017 {
1018         if (fl->stripe_type == STRIPE_SPARSE)
1019                 return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
1020         else
1021                 return j;
1022 }
1023
1024 /* The generic layer is about to remove the req from the commit list.
1025  * If this will make the bucket empty, it will need to put the lseg reference.
1026  */
1027 static void
1028 filelayout_clear_request_commit(struct nfs_page *req,
1029                                 struct nfs_commit_info *cinfo)
1030 {
1031         struct pnfs_layout_segment *freeme = NULL;
1032
1033         spin_lock(cinfo->lock);
1034         if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
1035                 goto out;
1036         cinfo->ds->nwritten--;
1037         if (list_is_singular(&req->wb_list)) {
1038                 struct pnfs_commit_bucket *bucket;
1039
1040                 bucket = list_first_entry(&req->wb_list,
1041                                           struct pnfs_commit_bucket,
1042                                           written);
1043                 freeme = bucket->wlseg;
1044                 bucket->wlseg = NULL;
1045         }
1046 out:
1047         nfs_request_remove_commit_list(req, cinfo);
1048         spin_unlock(cinfo->lock);
1049         pnfs_put_lseg(freeme);
1050 }
1051
1052 static struct list_head *
1053 filelayout_choose_commit_list(struct nfs_page *req,
1054                               struct pnfs_layout_segment *lseg,
1055                               struct nfs_commit_info *cinfo)
1056 {
1057         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
1058         u32 i, j;
1059         struct list_head *list;
1060         struct pnfs_commit_bucket *buckets;
1061
1062         if (fl->commit_through_mds)
1063                 return &cinfo->mds->list;
1064
1065         /* Note that we are calling nfs4_fl_calc_j_index on each page
1066          * that ends up being committed to a data server.  An attractive
1067          * alternative is to add a field to nfs_write_data and nfs_page
1068          * to store the value calculated in filelayout_write_pagelist
1069          * and just use that here.
1070          */
1071         j = nfs4_fl_calc_j_index(lseg, req_offset(req));
1072         i = select_bucket_index(fl, j);
1073         spin_lock(cinfo->lock);
1074         buckets = cinfo->ds->buckets;
1075         list = &buckets[i].written;
1076         if (list_empty(list)) {
1077                 /* Non-empty buckets hold a reference on the lseg.  That ref
1078                  * is normally transferred to the COMMIT call and released
1079                  * there.  It could also be released if the last req is pulled
1080                  * off due to a rewrite, in which case it will be done in
1081                  * filelayout_clear_request_commit
1082                  */
1083                 buckets[i].wlseg = pnfs_get_lseg(lseg);
1084         }
1085         set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
1086         cinfo->ds->nwritten++;
1087         spin_unlock(cinfo->lock);
1088         return list;
1089 }
1090
1091 static void
1092 filelayout_mark_request_commit(struct nfs_page *req,
1093                                struct pnfs_layout_segment *lseg,
1094                                struct nfs_commit_info *cinfo)
1095 {
1096         struct list_head *list;
1097
1098         list = filelayout_choose_commit_list(req, lseg, cinfo);
1099         nfs_request_add_commit_list(req, list, cinfo);
1100 }
1101
1102 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1103 {
1104         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
1105
1106         if (flseg->stripe_type == STRIPE_SPARSE)
1107                 return i;
1108         else
1109                 return nfs4_fl_calc_ds_index(lseg, i);
1110 }
1111
1112 static struct nfs_fh *
1113 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1114 {
1115         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
1116
1117         if (flseg->stripe_type == STRIPE_SPARSE) {
1118                 if (flseg->num_fh == 1)
1119                         i = 0;
1120                 else if (flseg->num_fh == 0)
1121                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
1122                         return NULL;
1123         }
1124         return flseg->fh_array[i];
1125 }
1126
1127 static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
1128 {
1129         struct pnfs_layout_segment *lseg = data->lseg;
1130         struct nfs4_pnfs_ds *ds;
1131         struct rpc_clnt *ds_clnt;
1132         u32 idx;
1133         struct nfs_fh *fh;
1134
1135         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1136         ds = nfs4_fl_prepare_ds(lseg, idx);
1137         if (!ds)
1138                 goto out_err;
1139
1140         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, data->inode);
1141         if (IS_ERR(ds_clnt))
1142                 goto out_err;
1143
1144         dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
1145                 data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count));
1146         data->commit_done_cb = filelayout_commit_done_cb;
1147         atomic_inc(&ds->ds_clp->cl_count);
1148         data->ds_clp = ds->ds_clp;
1149         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1150         if (fh)
1151                 data->args.fh = fh;
1152         return nfs_initiate_commit(ds_clnt, data,
1153                                    &filelayout_commit_call_ops, how,
1154                                    RPC_TASK_SOFTCONN);
1155 out_err:
1156         prepare_to_resend_writes(data);
1157         filelayout_commit_release(data);
1158         return -EAGAIN;
1159 }
1160
1161 static int
1162 transfer_commit_list(struct list_head *src, struct list_head *dst,
1163                      struct nfs_commit_info *cinfo, int max)
1164 {
1165         struct nfs_page *req, *tmp;
1166         int ret = 0;
1167
1168         list_for_each_entry_safe(req, tmp, src, wb_list) {
1169                 if (!nfs_lock_request(req))
1170                         continue;
1171                 kref_get(&req->wb_kref);
1172                 if (cond_resched_lock(cinfo->lock))
1173                         list_safe_reset_next(req, tmp, wb_list);
1174                 nfs_request_remove_commit_list(req, cinfo);
1175                 clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
1176                 nfs_list_add_request(req, dst);
1177                 ret++;
1178                 if ((ret == max) && !cinfo->dreq)
1179                         break;
1180         }
1181         return ret;
1182 }
1183
1184 /* Note called with cinfo->lock held. */
1185 static int
1186 filelayout_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
1187                                struct nfs_commit_info *cinfo,
1188                                int max)
1189 {
1190         struct list_head *src = &bucket->written;
1191         struct list_head *dst = &bucket->committing;
1192         int ret;
1193
1194         ret = transfer_commit_list(src, dst, cinfo, max);
1195         if (ret) {
1196                 cinfo->ds->nwritten -= ret;
1197                 cinfo->ds->ncommitting += ret;
1198                 bucket->clseg = bucket->wlseg;
1199                 if (list_empty(src))
1200                         bucket->wlseg = NULL;
1201                 else
1202                         pnfs_get_lseg(bucket->clseg);
1203         }
1204         return ret;
1205 }
1206
1207 /* Move reqs from written to committing lists, returning count of number moved.
1208  * Note called with cinfo->lock held.
1209  */
1210 static int filelayout_scan_commit_lists(struct nfs_commit_info *cinfo,
1211                                         int max)
1212 {
1213         int i, rv = 0, cnt;
1214
1215         for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
1216                 cnt = filelayout_scan_ds_commit_list(&cinfo->ds->buckets[i],
1217                                                      cinfo, max);
1218                 max -= cnt;
1219                 rv += cnt;
1220         }
1221         return rv;
1222 }
1223
1224 /* Pull everything off the committing lists and dump into @dst */
1225 static void filelayout_recover_commit_reqs(struct list_head *dst,
1226                                            struct nfs_commit_info *cinfo)
1227 {
1228         struct pnfs_commit_bucket *b;
1229         struct pnfs_layout_segment *freeme;
1230         int i;
1231
1232 restart:
1233         spin_lock(cinfo->lock);
1234         for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
1235                 if (transfer_commit_list(&b->written, dst, cinfo, 0)) {
1236                         freeme = b->wlseg;
1237                         b->wlseg = NULL;
1238                         spin_unlock(cinfo->lock);
1239                         pnfs_put_lseg(freeme);
1240                         goto restart;
1241                 }
1242         }
1243         cinfo->ds->nwritten = 0;
1244         spin_unlock(cinfo->lock);
1245 }
1246
1247 static unsigned int
1248 alloc_ds_commits(struct nfs_commit_info *cinfo, struct list_head *list)
1249 {
1250         struct pnfs_ds_commit_info *fl_cinfo;
1251         struct pnfs_commit_bucket *bucket;
1252         struct nfs_commit_data *data;
1253         int i, j;
1254         unsigned int nreq = 0;
1255         struct pnfs_layout_segment *freeme;
1256
1257         fl_cinfo = cinfo->ds;
1258         bucket = fl_cinfo->buckets;
1259         for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
1260                 if (list_empty(&bucket->committing))
1261                         continue;
1262                 data = nfs_commitdata_alloc();
1263                 if (!data)
1264                         break;
1265                 data->ds_commit_index = i;
1266                 spin_lock(cinfo->lock);
1267                 data->lseg = bucket->clseg;
1268                 bucket->clseg = NULL;
1269                 spin_unlock(cinfo->lock);
1270                 list_add(&data->pages, list);
1271                 nreq++;
1272         }
1273
1274         /* Clean up on error */
1275         for (j = i; j < fl_cinfo->nbuckets; j++, bucket++) {
1276                 if (list_empty(&bucket->committing))
1277                         continue;
1278                 nfs_retry_commit(&bucket->committing, bucket->clseg, cinfo);
1279                 spin_lock(cinfo->lock);
1280                 freeme = bucket->clseg;
1281                 bucket->clseg = NULL;
1282                 spin_unlock(cinfo->lock);
1283                 pnfs_put_lseg(freeme);
1284         }
1285         /* Caller will clean up entries put on list */
1286         return nreq;
1287 }
1288
1289 /* This follows nfs_commit_list pretty closely */
1290 static int
1291 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1292                            int how, struct nfs_commit_info *cinfo)
1293 {
1294         struct nfs_commit_data *data, *tmp;
1295         LIST_HEAD(list);
1296         unsigned int nreq = 0;
1297
1298         if (!list_empty(mds_pages)) {
1299                 data = nfs_commitdata_alloc();
1300                 if (data != NULL) {
1301                         data->lseg = NULL;
1302                         list_add(&data->pages, &list);
1303                         nreq++;
1304                 } else
1305                         nfs_retry_commit(mds_pages, NULL, cinfo);
1306         }
1307
1308         nreq += alloc_ds_commits(cinfo, &list);
1309
1310         if (nreq == 0) {
1311                 cinfo->completion_ops->error_cleanup(NFS_I(inode));
1312                 goto out;
1313         }
1314
1315         atomic_add(nreq, &cinfo->mds->rpcs_out);
1316
1317         list_for_each_entry_safe(data, tmp, &list, pages) {
1318                 list_del_init(&data->pages);
1319                 if (!data->lseg) {
1320                         nfs_init_commit(data, mds_pages, NULL, cinfo);
1321                         nfs_initiate_commit(NFS_CLIENT(inode), data,
1322                                             data->mds_ops, how, 0);
1323                 } else {
1324                         struct pnfs_commit_bucket *buckets;
1325
1326                         buckets = cinfo->ds->buckets;
1327                         nfs_init_commit(data, &buckets[data->ds_commit_index].committing, data->lseg, cinfo);
1328                         filelayout_initiate_commit(data, how);
1329                 }
1330         }
1331 out:
1332         cinfo->ds->ncommitting = 0;
1333         return PNFS_ATTEMPTED;
1334 }
1335
1336 static void
1337 filelayout_free_deveiceid_node(struct nfs4_deviceid_node *d)
1338 {
1339         nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
1340 }
1341
1342 static struct pnfs_layout_hdr *
1343 filelayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
1344 {
1345         struct nfs4_filelayout *flo;
1346
1347         flo = kzalloc(sizeof(*flo), gfp_flags);
1348         return flo != NULL ? &flo->generic_hdr : NULL;
1349 }
1350
1351 static void
1352 filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
1353 {
1354         kfree(FILELAYOUT_FROM_HDR(lo));
1355 }
1356
1357 static struct pnfs_ds_commit_info *
1358 filelayout_get_ds_info(struct inode *inode)
1359 {
1360         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1361
1362         if (layout == NULL)
1363                 return NULL;
1364         else
1365                 return &FILELAYOUT_FROM_HDR(layout)->commit_info;
1366 }
1367
1368 static struct pnfs_layoutdriver_type filelayout_type = {
1369         .id                     = LAYOUT_NFSV4_1_FILES,
1370         .name                   = "LAYOUT_NFSV4_1_FILES",
1371         .owner                  = THIS_MODULE,
1372         .alloc_layout_hdr       = filelayout_alloc_layout_hdr,
1373         .free_layout_hdr        = filelayout_free_layout_hdr,
1374         .alloc_lseg             = filelayout_alloc_lseg,
1375         .free_lseg              = filelayout_free_lseg,
1376         .pg_read_ops            = &filelayout_pg_read_ops,
1377         .pg_write_ops           = &filelayout_pg_write_ops,
1378         .get_ds_info            = &filelayout_get_ds_info,
1379         .mark_request_commit    = filelayout_mark_request_commit,
1380         .clear_request_commit   = filelayout_clear_request_commit,
1381         .scan_commit_lists      = filelayout_scan_commit_lists,
1382         .recover_commit_reqs    = filelayout_recover_commit_reqs,
1383         .commit_pagelist        = filelayout_commit_pagelist,
1384         .read_pagelist          = filelayout_read_pagelist,
1385         .write_pagelist         = filelayout_write_pagelist,
1386         .free_deviceid_node     = filelayout_free_deveiceid_node,
1387 };
1388
1389 static int __init nfs4filelayout_init(void)
1390 {
1391         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
1392                __func__);
1393         return pnfs_register_layoutdriver(&filelayout_type);
1394 }
1395
1396 static void __exit nfs4filelayout_exit(void)
1397 {
1398         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
1399                __func__);
1400         pnfs_unregister_layoutdriver(&filelayout_type);
1401 }
1402
1403 MODULE_ALIAS("nfs-layouttype4-1");
1404
1405 module_init(nfs4filelayout_init);
1406 module_exit(nfs4filelayout_exit);