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 #include <linux/backing-dev.h>
  36
  37 #include <linux/sunrpc/metrics.h>
  38
  39 #include "../nfs4session.h"
  40 #include "../internal.h"
  41 #include "../delegation.h"
  42 #include "filelayout.h"
  43 #include "../nfs4trace.h"
  44
  45 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  46
  47 MODULE_LICENSE("GPL");
  48 MODULE_AUTHOR("Dean Hildebrand <dhildebz@umich.edu>");
  49 MODULE_DESCRIPTION("The NFSv4 file layout driver");
  50
  51 #define FILELAYOUT_POLL_RETRY_MAX     (15*HZ)
  52
  53 static loff_t
  54 filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
  55                             loff_t offset)
  56 {
  57         u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
  58         u64 stripe_no;
  59         u32 rem;
  60
  61         offset -= flseg->pattern_offset;
  62         stripe_no = div_u64(offset, stripe_width);
  63         div_u64_rem(offset, flseg->stripe_unit, &rem);
  64
  65         return stripe_no * flseg->stripe_unit + rem;
  66 }
  67
  68 /* This function is used by the layout driver to calculate the
  69  * offset of the file on the dserver based on whether the
  70  * layout type is STRIPE_DENSE or STRIPE_SPARSE
  71  */
  72 static loff_t
  73 filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
  74 {
  75         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
  76
  77         switch (flseg->stripe_type) {
  78         case STRIPE_SPARSE:
  79                 return offset;
  80
  81         case STRIPE_DENSE:
  82                 return filelayout_get_dense_offset(flseg, offset);
  83         }
  84
  85         BUG();
  86 }
  87
  88 static void filelayout_reset_write(struct nfs_pgio_header *hdr)
  89 {
  90         struct rpc_task *task = &hdr->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                         hdr->task.tk_pid,
  96                         hdr->inode->i_sb->s_id,
  97                         (unsigned long long)NFS_FILEID(hdr->inode),
  98                         hdr->args.count,
  99                         (unsigned long long)hdr->args.offset);
 100
 101                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
 102         }
 103 }
 104
 105 static void filelayout_reset_read(struct nfs_pgio_header *hdr)
 106 {
 107         struct rpc_task *task = &hdr->task;
 108
 109         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 110                 dprintk("%s Reset task %5u for i/o through MDS "
 111                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 112                         hdr->task.tk_pid,
 113                         hdr->inode->i_sb->s_id,
 114                         (unsigned long long)NFS_FILEID(hdr->inode),
 115                         hdr->args.count,
 116                         (unsigned long long)hdr->args.offset);
 117
 118                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
 119         }
 120 }
 121
 122 static int filelayout_async_handle_error(struct rpc_task *task,
 123                                          struct nfs4_state *state,
 124                                          struct nfs_client *clp,
 125                                          struct pnfs_layout_segment *lseg)
 126 {
 127         struct pnfs_layout_hdr *lo = lseg->pls_layout;
 128         struct inode *inode = lo->plh_inode;
 129         struct nfs_server *mds_server = NFS_SERVER(inode);
 130         struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
 131         struct nfs_client *mds_client = mds_server->nfs_client;
 132         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 133
 134         if (task->tk_status >= 0)
 135                 return 0;
 136
 137         switch (task->tk_status) {
 138         /* MDS state errors */
 139         case -NFS4ERR_DELEG_REVOKED:
 140         case -NFS4ERR_ADMIN_REVOKED:
 141         case -NFS4ERR_BAD_STATEID:
 142         case -NFS4ERR_OPENMODE:
 143                 if (state == NULL)
 144                         break;
 145                 if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 146                         goto out_bad_stateid;
 147                 goto wait_on_recovery;
 148         case -NFS4ERR_EXPIRED:
 149                 if (state != NULL) {
 150                         if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 151                                 goto out_bad_stateid;
 152                 }
 153                 nfs4_schedule_lease_recovery(mds_client);
 154                 goto wait_on_recovery;
 155         /* DS session errors */
 156         case -NFS4ERR_BADSESSION:
 157         case -NFS4ERR_BADSLOT:
 158         case -NFS4ERR_BAD_HIGH_SLOT:
 159         case -NFS4ERR_DEADSESSION:
 160         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 161         case -NFS4ERR_SEQ_FALSE_RETRY:
 162         case -NFS4ERR_SEQ_MISORDERED:
 163                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 164                         "flags 0x%x\n", __func__, task->tk_status,
 165                         clp->cl_exchange_flags);
 166                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
 167                 break;
 168         case -NFS4ERR_DELAY:
 169         case -NFS4ERR_GRACE:
 170                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
 171                 break;
 172         case -NFS4ERR_RETRY_UNCACHED_REP:
 173                 break;
 174         /* Invalidate Layout errors */
 175         case -NFS4ERR_PNFS_NO_LAYOUT:
 176         case -ESTALE:           /* mapped NFS4ERR_STALE */
 177         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
 178         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
 179         case -NFS4ERR_FHEXPIRED:
 180         case -NFS4ERR_WRONG_TYPE:
 181                 dprintk("%s Invalid layout error %d\n", __func__,
 182                         task->tk_status);
 183                 /*
 184                  * Destroy layout so new i/o will get a new layout.
 185                  * Layout will not be destroyed until all current lseg
 186                  * references are put. Mark layout as invalid to resend failed
 187                  * i/o and all i/o waiting on the slot table to the MDS until
 188                  * layout is destroyed and a new valid layout is obtained.
 189                  */
 190                 pnfs_destroy_layout(NFS_I(inode));
 191                 rpc_wake_up(&tbl->slot_tbl_waitq);
 192                 goto reset;
 193         /* RPC connection errors */
 194         case -ECONNREFUSED:
 195         case -EHOSTDOWN:
 196         case -EHOSTUNREACH:
 197         case -ENETUNREACH:
 198         case -EIO:
 199         case -ETIMEDOUT:
 200         case -EPIPE:
 201                 dprintk("%s DS connection error %d\n", __func__,
 202                         task->tk_status);
 203                 nfs4_mark_deviceid_unavailable(devid);
 204                 pnfs_error_mark_layout_for_return(inode, lseg);
 205                 rpc_wake_up(&tbl->slot_tbl_waitq);
 206                 /* fall through */
 207         default:
 208 reset:
 209                 dprintk("%s Retry through MDS. Error %d\n", __func__,
 210                         task->tk_status);
 211                 return -NFS4ERR_RESET_TO_MDS;
 212         }
 213 out:
 214         task->tk_status = 0;
 215         return -EAGAIN;
 216 out_bad_stateid:
 217         task->tk_status = -EIO;
 218         return 0;
 219 wait_on_recovery:
 220         rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
 221         if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
 222                 rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
 223         goto out;
 224 }
 225
 226 /* NFS_PROTO call done callback routines */
 227
 228 static int filelayout_read_done_cb(struct rpc_task *task,
 229                                 struct nfs_pgio_header *hdr)
 230 {
 231         int err;
 232
 233         trace_nfs4_pnfs_read(hdr, task->tk_status);
 234         err = filelayout_async_handle_error(task, hdr->args.context->state,
 235                                             hdr->ds_clp, hdr->lseg);
 236
 237         switch (err) {
 238         case -NFS4ERR_RESET_TO_MDS:
 239                 filelayout_reset_read(hdr);
 240                 return task->tk_status;
 241         case -EAGAIN:
 242                 rpc_restart_call_prepare(task);
 243                 return -EAGAIN;
 244         }
 245
 246         return 0;
 247 }
 248
 249 /*
 250  * We reference the rpc_cred of the first WRITE that triggers the need for
 251  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
 252  * rfc5661 is not clear about which credential should be used.
 253  */
 254 static void
 255 filelayout_set_layoutcommit(struct nfs_pgio_header *hdr)
 256 {
 257
 258         if (FILELAYOUT_LSEG(hdr->lseg)->commit_through_mds ||
 259             hdr->res.verf->committed != NFS_DATA_SYNC)
 260                 return;
 261
 262         pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
 263                         hdr->mds_offset + hdr->res.count);
 264         dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
 265                 (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
 266 }
 267
 268 bool
 269 filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node)
 270 {
 271         return filelayout_test_devid_invalid(node) ||
 272                 nfs4_test_deviceid_unavailable(node);
 273 }
 274
 275 static bool
 276 filelayout_reset_to_mds(struct pnfs_layout_segment *lseg)
 277 {
 278         struct nfs4_deviceid_node *node = FILELAYOUT_DEVID_NODE(lseg);
 279
 280         return filelayout_test_devid_unavailable(node);
 281 }
 282
 283 /*
 284  * Call ops for the async read/write cases
 285  * In the case of dense layouts, the offset needs to be reset to its
 286  * original value.
 287  */
 288 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 289 {
 290         struct nfs_pgio_header *hdr = data;
 291
 292         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
 293                 rpc_exit(task, -EIO);
 294                 return;
 295         }
 296         if (filelayout_reset_to_mds(hdr->lseg)) {
 297                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 298                 filelayout_reset_read(hdr);
 299                 rpc_exit(task, 0);
 300                 return;
 301         }
 302         hdr->pgio_done_cb = filelayout_read_done_cb;
 303
 304         if (nfs41_setup_sequence(hdr->ds_clp->cl_session,
 305                         &hdr->args.seq_args,
 306                         &hdr->res.seq_res,
 307                         task))
 308                 return;
 309         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
 310                         hdr->args.lock_context, FMODE_READ) == -EIO)
 311                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 312 }
 313
 314 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 315 {
 316         struct nfs_pgio_header *hdr = data;
 317
 318         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
 319
 320         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
 321             task->tk_status == 0) {
 322                 nfs41_sequence_done(task, &hdr->res.seq_res);
 323                 return;
 324         }
 325
 326         /* Note this may cause RPC to be resent */
 327         hdr->mds_ops->rpc_call_done(task, data);
 328 }
 329
 330 static void filelayout_read_count_stats(struct rpc_task *task, void *data)
 331 {
 332         struct nfs_pgio_header *hdr = data;
 333
 334         rpc_count_iostats(task, NFS_SERVER(hdr->inode)->client->cl_metrics);
 335 }
 336
 337 static int filelayout_write_done_cb(struct rpc_task *task,
 338                                 struct nfs_pgio_header *hdr)
 339 {
 340         int err;
 341
 342         trace_nfs4_pnfs_write(hdr, task->tk_status);
 343         err = filelayout_async_handle_error(task, hdr->args.context->state,
 344                                             hdr->ds_clp, hdr->lseg);
 345
 346         switch (err) {
 347         case -NFS4ERR_RESET_TO_MDS:
 348                 filelayout_reset_write(hdr);
 349                 return task->tk_status;
 350         case -EAGAIN:
 351                 rpc_restart_call_prepare(task);
 352                 return -EAGAIN;
 353         }
 354
 355         filelayout_set_layoutcommit(hdr);
 356         return 0;
 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         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
 365         err = filelayout_async_handle_error(task, NULL, data->ds_clp,
 366                                             data->lseg);
 367
 368         switch (err) {
 369         case -NFS4ERR_RESET_TO_MDS:
 370                 pnfs_generic_prepare_to_resend_writes(data);
 371                 return -EAGAIN;
 372         case -EAGAIN:
 373                 rpc_restart_call_prepare(task);
 374                 return -EAGAIN;
 375         }
 376
 377         if (data->verf.committed == NFS_UNSTABLE)
 378                 pnfs_set_layoutcommit(data->inode, data->lseg, data->lwb);
 379
 380         return 0;
 381 }
 382
 383 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 384 {
 385         struct nfs_pgio_header *hdr = data;
 386
 387         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
 388                 rpc_exit(task, -EIO);
 389                 return;
 390         }
 391         if (filelayout_reset_to_mds(hdr->lseg)) {
 392                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 393                 filelayout_reset_write(hdr);
 394                 rpc_exit(task, 0);
 395                 return;
 396         }
 397         if (nfs41_setup_sequence(hdr->ds_clp->cl_session,
 398                         &hdr->args.seq_args,
 399                         &hdr->res.seq_res,
 400                         task))
 401                 return;
 402         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
 403                         hdr->args.lock_context, FMODE_WRITE) == -EIO)
 404                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 405 }
 406
 407 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 408 {
 409         struct nfs_pgio_header *hdr = data;
 410
 411         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
 412             task->tk_status == 0) {
 413                 nfs41_sequence_done(task, &hdr->res.seq_res);
 414                 return;
 415         }
 416
 417         /* Note this may cause RPC to be resent */
 418         hdr->mds_ops->rpc_call_done(task, data);
 419 }
 420
 421 static void filelayout_write_count_stats(struct rpc_task *task, void *data)
 422 {
 423         struct nfs_pgio_header *hdr = data;
 424
 425         rpc_count_iostats(task, NFS_SERVER(hdr->inode)->client->cl_metrics);
 426 }
 427
 428 static void filelayout_commit_prepare(struct rpc_task *task, void *data)
 429 {
 430         struct nfs_commit_data *wdata = data;
 431
 432         nfs41_setup_sequence(wdata->ds_clp->cl_session,
 433                         &wdata->args.seq_args,
 434                         &wdata->res.seq_res,
 435                         task);
 436 }
 437
 438 static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
 439 {
 440         struct nfs_commit_data *cdata = data;
 441
 442         rpc_count_iostats(task, NFS_SERVER(cdata->inode)->client->cl_metrics);
 443 }
 444
 445 static const struct rpc_call_ops filelayout_read_call_ops = {
 446         .rpc_call_prepare = filelayout_read_prepare,
 447         .rpc_call_done = filelayout_read_call_done,
 448         .rpc_count_stats = filelayout_read_count_stats,
 449         .rpc_release = pnfs_generic_rw_release,
 450 };
 451
 452 static const struct rpc_call_ops filelayout_write_call_ops = {
 453         .rpc_call_prepare = filelayout_write_prepare,
 454         .rpc_call_done = filelayout_write_call_done,
 455         .rpc_count_stats = filelayout_write_count_stats,
 456         .rpc_release = pnfs_generic_rw_release,
 457 };
 458
 459 static const struct rpc_call_ops filelayout_commit_call_ops = {
 460         .rpc_call_prepare = filelayout_commit_prepare,
 461         .rpc_call_done = pnfs_generic_write_commit_done,
 462         .rpc_count_stats = filelayout_commit_count_stats,
 463         .rpc_release = pnfs_generic_commit_release,
 464 };
 465
 466 static enum pnfs_try_status
 467 filelayout_read_pagelist(struct nfs_pgio_header *hdr)
 468 {
 469         struct pnfs_layout_segment *lseg = hdr->lseg;
 470         struct nfs4_pnfs_ds *ds;
 471         struct rpc_clnt *ds_clnt;
 472         loff_t offset = hdr->args.offset;
 473         u32 j, idx;
 474         struct nfs_fh *fh;
 475
 476         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
 477                 __func__, hdr->inode->i_ino,
 478                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
 479
 480         /* Retrieve the correct rpc_client for the byte range */
 481         j = nfs4_fl_calc_j_index(lseg, offset);
 482         idx = nfs4_fl_calc_ds_index(lseg, j);
 483         ds = nfs4_fl_prepare_ds(lseg, idx);
 484         if (!ds)
 485                 return PNFS_NOT_ATTEMPTED;
 486
 487         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 488         if (IS_ERR(ds_clnt))
 489                 return PNFS_NOT_ATTEMPTED;
 490
 491         dprintk("%s USE DS: %s cl_count %d\n", __func__,
 492                 ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 493
 494         /* No multipath support. Use first DS */
 495         atomic_inc(&ds->ds_clp->cl_count);
 496         hdr->ds_clp = ds->ds_clp;
 497         hdr->ds_commit_idx = idx;
 498         fh = nfs4_fl_select_ds_fh(lseg, j);
 499         if (fh)
 500                 hdr->args.fh = fh;
 501
 502         hdr->args.offset = filelayout_get_dserver_offset(lseg, offset);
 503         hdr->mds_offset = offset;
 504
 505         /* Perform an asynchronous read to ds */
 506         nfs_initiate_pgio(ds_clnt, hdr, hdr->cred,
 507                           NFS_PROTO(hdr->inode), &filelayout_read_call_ops,
 508                           0, RPC_TASK_SOFTCONN);
 509         return PNFS_ATTEMPTED;
 510 }
 511
 512 /* Perform async writes. */
 513 static enum pnfs_try_status
 514 filelayout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 515 {
 516         struct pnfs_layout_segment *lseg = hdr->lseg;
 517         struct nfs4_pnfs_ds *ds;
 518         struct rpc_clnt *ds_clnt;
 519         loff_t offset = hdr->args.offset;
 520         u32 j, idx;
 521         struct nfs_fh *fh;
 522
 523         /* Retrieve the correct rpc_client for the byte range */
 524         j = nfs4_fl_calc_j_index(lseg, offset);
 525         idx = nfs4_fl_calc_ds_index(lseg, j);
 526         ds = nfs4_fl_prepare_ds(lseg, idx);
 527         if (!ds)
 528                 return PNFS_NOT_ATTEMPTED;
 529
 530         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 531         if (IS_ERR(ds_clnt))
 532                 return PNFS_NOT_ATTEMPTED;
 533
 534         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d\n",
 535                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
 536                 offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 537
 538         hdr->pgio_done_cb = filelayout_write_done_cb;
 539         atomic_inc(&ds->ds_clp->cl_count);
 540         hdr->ds_clp = ds->ds_clp;
 541         hdr->ds_commit_idx = idx;
 542         fh = nfs4_fl_select_ds_fh(lseg, j);
 543         if (fh)
 544                 hdr->args.fh = fh;
 545         hdr->args.offset = filelayout_get_dserver_offset(lseg, offset);
 546
 547         /* Perform an asynchronous write */
 548         nfs_initiate_pgio(ds_clnt, hdr, hdr->cred,
 549                           NFS_PROTO(hdr->inode), &filelayout_write_call_ops,
 550                           sync, RPC_TASK_SOFTCONN);
 551         return PNFS_ATTEMPTED;
 552 }
 553
 554 /*
 555  * filelayout_check_layout()
 556  *
 557  * Make sure layout segment parameters are sane WRT the device.
 558  * At this point no generic layer initialization of the lseg has occurred,
 559  * and nothing has been added to the layout_hdr cache.
 560  *
 561  */
 562 static int
 563 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 564                         struct nfs4_filelayout_segment *fl,
 565                         struct nfs4_layoutget_res *lgr,
 566                         struct nfs4_deviceid *id,
 567                         gfp_t gfp_flags)
 568 {
 569         struct nfs4_deviceid_node *d;
 570         struct nfs4_file_layout_dsaddr *dsaddr;
 571         int status = -EINVAL;
 572
 573         dprintk("--> %s\n", __func__);
 574
 575         /* FIXME: remove this check when layout segment support is added */
 576         if (lgr->range.offset != 0 ||
 577             lgr->range.length != NFS4_MAX_UINT64) {
 578                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 579                         __func__);
 580                 goto out;
 581         }
 582
 583         if (fl->pattern_offset > lgr->range.offset) {
 584                 dprintk("%s pattern_offset %lld too large\n",
 585                                 __func__, fl->pattern_offset);
 586                 goto out;
 587         }
 588
 589         if (!fl->stripe_unit) {
 590                 dprintk("%s Invalid stripe unit (%u)\n",
 591                         __func__, fl->stripe_unit);
 592                 goto out;
 593         }
 594
 595         /* find and reference the deviceid */
 596         d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode), id,
 597                         lo->plh_lc_cred, gfp_flags);
 598         if (d == NULL)
 599                 goto out;
 600
 601         dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 602         /* Found deviceid is unavailable */
 603         if (filelayout_test_devid_unavailable(&dsaddr->id_node))
 604                 goto out_put;
 605
 606         fl->dsaddr = dsaddr;
 607
 608         if (fl->first_stripe_index >= dsaddr->stripe_count) {
 609                 dprintk("%s Bad first_stripe_index %u\n",
 610                                 __func__, fl->first_stripe_index);
 611                 goto out_put;
 612         }
 613
 614         if ((fl->stripe_type == STRIPE_SPARSE &&
 615             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 616             (fl->stripe_type == STRIPE_DENSE &&
 617             fl->num_fh != dsaddr->stripe_count)) {
 618                 dprintk("%s num_fh %u not valid for given packing\n",
 619                         __func__, fl->num_fh);
 620                 goto out_put;
 621         }
 622
 623         status = 0;
 624 out:
 625         dprintk("--> %s returns %d\n", __func__, status);
 626         return status;
 627 out_put:
 628         nfs4_fl_put_deviceid(dsaddr);
 629         goto out;
 630 }
 631
 632 static void _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 633 {
 634         int i;
 635
 636         if (fl->fh_array) {
 637                 for (i = 0; i < fl->num_fh; i++) {
 638                         if (!fl->fh_array[i])
 639                                 break;
 640                         kfree(fl->fh_array[i]);
 641                 }
 642                 kfree(fl->fh_array);
 643         }
 644         kfree(fl);
 645 }
 646
 647 static int
 648 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 649                          struct nfs4_filelayout_segment *fl,
 650                          struct nfs4_layoutget_res *lgr,
 651                          struct nfs4_deviceid *id,
 652                          gfp_t gfp_flags)
 653 {
 654         struct xdr_stream stream;
 655         struct xdr_buf buf;
 656         struct page *scratch;
 657         __be32 *p;
 658         uint32_t nfl_util;
 659         int i;
 660
 661         dprintk("%s: set_layout_map Begin\n", __func__);
 662
 663         scratch = alloc_page(gfp_flags);
 664         if (!scratch)
 665                 return -ENOMEM;
 666
 667         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
 668         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 669
 670         /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
 671          * num_fh (4) */
 672         p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
 673         if (unlikely(!p))
 674                 goto out_err;
 675
 676         memcpy(id, p, sizeof(*id));
 677         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 678         nfs4_print_deviceid(id);
 679
 680         nfl_util = be32_to_cpup(p++);
 681         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 682                 fl->commit_through_mds = 1;
 683         if (nfl_util & NFL4_UFLG_DENSE)
 684                 fl->stripe_type = STRIPE_DENSE;
 685         else
 686                 fl->stripe_type = STRIPE_SPARSE;
 687         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 688
 689         fl->first_stripe_index = be32_to_cpup(p++);
 690         p = xdr_decode_hyper(p, &fl->pattern_offset);
 691         fl->num_fh = be32_to_cpup(p++);
 692
 693         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 694                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 695                 fl->pattern_offset);
 696
 697         /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
 698          * Futher checking is done in filelayout_check_layout */
 699         if (fl->num_fh >
 700             max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
 701                 goto out_err;
 702
 703         if (fl->num_fh > 0) {
 704                 fl->fh_array = kcalloc(fl->num_fh, sizeof(fl->fh_array[0]),
 705                                        gfp_flags);
 706                 if (!fl->fh_array)
 707                         goto out_err;
 708         }
 709
 710         for (i = 0; i < fl->num_fh; i++) {
 711                 /* Do we want to use a mempool here? */
 712                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
 713                 if (!fl->fh_array[i])
 714                         goto out_err;
 715
 716                 p = xdr_inline_decode(&stream, 4);
 717                 if (unlikely(!p))
 718                         goto out_err;
 719                 fl->fh_array[i]->size = be32_to_cpup(p++);
 720                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
 721                         printk(KERN_ERR "NFS: Too big fh %d received %d\n",
 722                                i, fl->fh_array[i]->size);
 723                         goto out_err;
 724                 }
 725
 726                 p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
 727                 if (unlikely(!p))
 728                         goto out_err;
 729                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 730                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 731                         fl->fh_array[i]->size);
 732         }
 733
 734         __free_page(scratch);
 735         return 0;
 736
 737 out_err:
 738         __free_page(scratch);
 739         return -EIO;
 740 }
 741
 742 static void
 743 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 744 {
 745         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 746
 747         dprintk("--> %s\n", __func__);
 748         nfs4_fl_put_deviceid(fl->dsaddr);
 749         /* This assumes a single RW lseg */
 750         if (lseg->pls_range.iomode == IOMODE_RW) {
 751                 struct nfs4_filelayout *flo;
 752
 753                 flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
 754                 flo->commit_info.nbuckets = 0;
 755                 kfree(flo->commit_info.buckets);
 756                 flo->commit_info.buckets = NULL;
 757         }
 758         _filelayout_free_lseg(fl);
 759 }
 760
 761 static int
 762 filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 763                              struct nfs_commit_info *cinfo,
 764                              gfp_t gfp_flags)
 765 {
 766         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 767         struct pnfs_commit_bucket *buckets;
 768         int size, i;
 769
 770         if (fl->commit_through_mds)
 771                 return 0;
 772
 773         size = (fl->stripe_type == STRIPE_SPARSE) ?
 774                 fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
 775
 776         if (cinfo->ds->nbuckets >= size) {
 777                 /* This assumes there is only one IOMODE_RW lseg.  What
 778                  * we really want to do is have a layout_hdr level
 779                  * dictionary of <multipath_list4, fh> keys, each
 780                  * associated with a struct list_head, populated by calls
 781                  * to filelayout_write_pagelist().
 782                  * */
 783                 return 0;
 784         }
 785
 786         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 787                           gfp_flags);
 788         if (!buckets)
 789                 return -ENOMEM;
 790         for (i = 0; i < size; i++) {
 791                 INIT_LIST_HEAD(&buckets[i].written);
 792                 INIT_LIST_HEAD(&buckets[i].committing);
 793                 /* mark direct verifier as unset */
 794                 buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW;
 795         }
 796
 797         spin_lock(cinfo->lock);
 798         if (cinfo->ds->nbuckets >= size)
 799                 goto out;
 800         for (i = 0; i < cinfo->ds->nbuckets; i++) {
 801                 list_splice(&cinfo->ds->buckets[i].written,
 802                             &buckets[i].written);
 803                 list_splice(&cinfo->ds->buckets[i].committing,
 804                             &buckets[i].committing);
 805                 buckets[i].direct_verf.committed =
 806                         cinfo->ds->buckets[i].direct_verf.committed;
 807                 buckets[i].wlseg = cinfo->ds->buckets[i].wlseg;
 808                 buckets[i].clseg = cinfo->ds->buckets[i].clseg;
 809         }
 810         swap(cinfo->ds->buckets, buckets);
 811         cinfo->ds->nbuckets = size;
 812 out:
 813         spin_unlock(cinfo->lock);
 814         kfree(buckets);
 815         return 0;
 816 }
 817
 818 static struct pnfs_layout_segment *
 819 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 820                       struct nfs4_layoutget_res *lgr,
 821                       gfp_t gfp_flags)
 822 {
 823         struct nfs4_filelayout_segment *fl;
 824         int rc;
 825         struct nfs4_deviceid id;
 826
 827         dprintk("--> %s\n", __func__);
 828         fl = kzalloc(sizeof(*fl), gfp_flags);
 829         if (!fl)
 830                 return NULL;
 831
 832         rc = filelayout_decode_layout(layoutid, fl, lgr, &id, gfp_flags);
 833         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id, gfp_flags)) {
 834                 _filelayout_free_lseg(fl);
 835                 return NULL;
 836         }
 837         return &fl->generic_hdr;
 838 }
 839
 840 /*
 841  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 842  *
 843  * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
 844  * of bytes (maximum @req->wb_bytes) that can be coalesced.
 845  */
 846 static size_t
 847 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 848                    struct nfs_page *req)
 849 {
 850         unsigned int size;
 851         u64 p_stripe, r_stripe;
 852         u32 stripe_offset;
 853         u64 segment_offset = pgio->pg_lseg->pls_range.offset;
 854         u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 855
 856         /* calls nfs_generic_pg_test */
 857         size = pnfs_generic_pg_test(pgio, prev, req);
 858         if (!size)
 859                 return 0;
 860
 861         /* see if req and prev are in the same stripe */
 862         if (prev) {
 863                 p_stripe = (u64)req_offset(prev) - segment_offset;
 864                 r_stripe = (u64)req_offset(req) - segment_offset;
 865                 do_div(p_stripe, stripe_unit);
 866                 do_div(r_stripe, stripe_unit);
 867
 868                 if (p_stripe != r_stripe)
 869                         return 0;
 870         }
 871
 872         /* calculate remaining bytes in the current stripe */
 873         div_u64_rem((u64)req_offset(req) - segment_offset,
 874                         stripe_unit,
 875                         &stripe_offset);
 876         WARN_ON_ONCE(stripe_offset > stripe_unit);
 877         if (stripe_offset >= stripe_unit)
 878                 return 0;
 879         return min(stripe_unit - (unsigned int)stripe_offset, size);
 880 }
 881
 882 static void
 883 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 884                         struct nfs_page *req)
 885 {
 886         if (!pgio->pg_lseg)
 887                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 888                                            req->wb_context,
 889                                            0,
 890                                            NFS4_MAX_UINT64,
 891                                            IOMODE_READ,
 892                                            GFP_KERNEL);
 893         /* If no lseg, fall back to read through mds */
 894         if (pgio->pg_lseg == NULL)
 895                 nfs_pageio_reset_read_mds(pgio);
 896 }
 897
 898 static void
 899 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 900                          struct nfs_page *req)
 901 {
 902         struct nfs_commit_info cinfo;
 903         int status;
 904
 905         if (!pgio->pg_lseg)
 906                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 907                                            req->wb_context,
 908                                            0,
 909                                            NFS4_MAX_UINT64,
 910                                            IOMODE_RW,
 911                                            GFP_NOFS);
 912         /* If no lseg, fall back to write through mds */
 913         if (pgio->pg_lseg == NULL)
 914                 goto out_mds;
 915         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 916         status = filelayout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 917         if (status < 0) {
 918                 pnfs_put_lseg(pgio->pg_lseg);
 919                 pgio->pg_lseg = NULL;
 920                 goto out_mds;
 921         }
 922         return;
 923 out_mds:
 924         nfs_pageio_reset_write_mds(pgio);
 925 }
 926
 927 static const struct nfs_pageio_ops filelayout_pg_read_ops = {
 928         .pg_init = filelayout_pg_init_read,
 929         .pg_test = filelayout_pg_test,
 930         .pg_doio = pnfs_generic_pg_readpages,
 931         .pg_cleanup = pnfs_generic_pg_cleanup,
 932 };
 933
 934 static const struct nfs_pageio_ops filelayout_pg_write_ops = {
 935         .pg_init = filelayout_pg_init_write,
 936         .pg_test = filelayout_pg_test,
 937         .pg_doio = pnfs_generic_pg_writepages,
 938         .pg_cleanup = pnfs_generic_pg_cleanup,
 939 };
 940
 941 static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
 942 {
 943         if (fl->stripe_type == STRIPE_SPARSE)
 944                 return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
 945         else
 946                 return j;
 947 }
 948
 949 static void
 950 filelayout_mark_request_commit(struct nfs_page *req,
 951                                struct pnfs_layout_segment *lseg,
 952                                struct nfs_commit_info *cinfo,
 953                                u32 ds_commit_idx)
 954
 955 {
 956         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 957         u32 i, j;
 958
 959         if (fl->commit_through_mds) {
 960                 nfs_request_add_commit_list(req, &cinfo->mds->list, cinfo);
 961         } else {
 962                 /* Note that we are calling nfs4_fl_calc_j_index on each page
 963                  * that ends up being committed to a data server.  An attractive
 964                  * alternative is to add a field to nfs_write_data and nfs_page
 965                  * to store the value calculated in filelayout_write_pagelist
 966                  * and just use that here.
 967                  */
 968                 j = nfs4_fl_calc_j_index(lseg, req_offset(req));
 969                 i = select_bucket_index(fl, j);
 970                 pnfs_layout_mark_request_commit(req, lseg, cinfo, i);
 971         }
 972 }
 973
 974 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 975 {
 976         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 977
 978         if (flseg->stripe_type == STRIPE_SPARSE)
 979                 return i;
 980         else
 981                 return nfs4_fl_calc_ds_index(lseg, i);
 982 }
 983
 984 static struct nfs_fh *
 985 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 986 {
 987         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 988
 989         if (flseg->stripe_type == STRIPE_SPARSE) {
 990                 if (flseg->num_fh == 1)
 991                         i = 0;
 992                 else if (flseg->num_fh == 0)
 993                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
 994                         return NULL;
 995         }
 996         return flseg->fh_array[i];
 997 }
 998
 999 static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
1000 {
1001         struct pnfs_layout_segment *lseg = data->lseg;
1002         struct nfs4_pnfs_ds *ds;
1003         struct rpc_clnt *ds_clnt;
1004         u32 idx;
1005         struct nfs_fh *fh;
1006
1007         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1008         ds = nfs4_fl_prepare_ds(lseg, idx);
1009         if (!ds)
1010                 goto out_err;
1011
1012         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, data->inode);
1013         if (IS_ERR(ds_clnt))
1014                 goto out_err;
1015
1016         dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
1017                 data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count));
1018         data->commit_done_cb = filelayout_commit_done_cb;
1019         atomic_inc(&ds->ds_clp->cl_count);
1020         data->ds_clp = ds->ds_clp;
1021         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1022         if (fh)
1023                 data->args.fh = fh;
1024         return nfs_initiate_commit(ds_clnt, data, NFS_PROTO(data->inode),
1025                                    &filelayout_commit_call_ops, how,
1026                                    RPC_TASK_SOFTCONN);
1027 out_err:
1028         pnfs_generic_prepare_to_resend_writes(data);
1029         pnfs_generic_commit_release(data);
1030         return -EAGAIN;
1031 }
1032
1033 /* filelayout_search_commit_reqs - Search lists in @cinfo for the head reqest
1034  *                                 for @page
1035  * @cinfo - commit info for current inode
1036  * @page - page to search for matching head request
1037  *
1038  * Returns a the head request if one is found, otherwise returns NULL.
1039  */
1040 static struct nfs_page *
1041 filelayout_search_commit_reqs(struct nfs_commit_info *cinfo, struct page *page)
1042 {
1043         struct nfs_page *freq, *t;
1044         struct pnfs_commit_bucket *b;
1045         int i;
1046
1047         /* Linearly search the commit lists for each bucket until a matching
1048          * request is found */
1049         for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
1050                 list_for_each_entry_safe(freq, t, &b->written, wb_list) {
1051                         if (freq->wb_page == page)
1052                                 return freq->wb_head;
1053                 }
1054                 list_for_each_entry_safe(freq, t, &b->committing, wb_list) {
1055                         if (freq->wb_page == page)
1056                                 return freq->wb_head;
1057                 }
1058         }
1059
1060         return NULL;
1061 }
1062
1063 static int
1064 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1065                            int how, struct nfs_commit_info *cinfo)
1066 {
1067         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1068                                             filelayout_initiate_commit);
1069 }
1070
1071 static struct nfs4_deviceid_node *
1072 filelayout_alloc_deviceid_node(struct nfs_server *server,
1073                 struct pnfs_device *pdev, gfp_t gfp_flags)
1074 {
1075         struct nfs4_file_layout_dsaddr *dsaddr;
1076
1077         dsaddr = nfs4_fl_alloc_deviceid_node(server, pdev, gfp_flags);
1078         if (!dsaddr)
1079                 return NULL;
1080         return &dsaddr->id_node;
1081 }
1082
1083 static void
1084 filelayout_free_deviceid_node(struct nfs4_deviceid_node *d)
1085 {
1086         nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
1087 }
1088
1089 static struct pnfs_layout_hdr *
1090 filelayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
1091 {
1092         struct nfs4_filelayout *flo;
1093
1094         flo = kzalloc(sizeof(*flo), gfp_flags);
1095         return flo != NULL ? &flo->generic_hdr : NULL;
1096 }
1097
1098 static void
1099 filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
1100 {
1101         kfree(FILELAYOUT_FROM_HDR(lo));
1102 }
1103
1104 static struct pnfs_ds_commit_info *
1105 filelayout_get_ds_info(struct inode *inode)
1106 {
1107         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1108
1109         if (layout == NULL)
1110                 return NULL;
1111         else
1112                 return &FILELAYOUT_FROM_HDR(layout)->commit_info;
1113 }
1114
1115 static struct pnfs_layoutdriver_type filelayout_type = {
1116         .id                     = LAYOUT_NFSV4_1_FILES,
1117         .name                   = "LAYOUT_NFSV4_1_FILES",
1118         .owner                  = THIS_MODULE,
1119         .alloc_layout_hdr       = filelayout_alloc_layout_hdr,
1120         .free_layout_hdr        = filelayout_free_layout_hdr,
1121         .alloc_lseg             = filelayout_alloc_lseg,
1122         .free_lseg              = filelayout_free_lseg,
1123         .pg_read_ops            = &filelayout_pg_read_ops,
1124         .pg_write_ops           = &filelayout_pg_write_ops,
1125         .get_ds_info            = &filelayout_get_ds_info,
1126         .mark_request_commit    = filelayout_mark_request_commit,
1127         .clear_request_commit   = pnfs_generic_clear_request_commit,
1128         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
1129         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
1130         .search_commit_reqs     = filelayout_search_commit_reqs,
1131         .commit_pagelist        = filelayout_commit_pagelist,
1132         .read_pagelist          = filelayout_read_pagelist,
1133         .write_pagelist         = filelayout_write_pagelist,
1134         .alloc_deviceid_node    = filelayout_alloc_deviceid_node,
1135         .free_deviceid_node     = filelayout_free_deviceid_node,
1136         .sync                   = pnfs_nfs_generic_sync,
1137 };
1138
1139 static int __init nfs4filelayout_init(void)
1140 {
1141         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
1142                __func__);
1143         return pnfs_register_layoutdriver(&filelayout_type);
1144 }
1145
1146 static void __exit nfs4filelayout_exit(void)
1147 {
1148         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
1149                __func__);
1150         pnfs_unregister_layoutdriver(&filelayout_type);
1151 }
1152
1153 MODULE_ALIAS("nfs-layouttype4-1");
1154
1155 module_init(nfs4filelayout_init);
1156 module_exit(nfs4filelayout_exit);