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         pnfs_set_layoutcommit(data->inode, data->lseg, data->lwb);
 378
 379         return 0;
 380 }
 381
 382 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 383 {
 384         struct nfs_pgio_header *hdr = data;
 385
 386         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
 387                 rpc_exit(task, -EIO);
 388                 return;
 389         }
 390         if (filelayout_reset_to_mds(hdr->lseg)) {
 391                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 392                 filelayout_reset_write(hdr);
 393                 rpc_exit(task, 0);
 394                 return;
 395         }
 396         if (nfs41_setup_sequence(hdr->ds_clp->cl_session,
 397                         &hdr->args.seq_args,
 398                         &hdr->res.seq_res,
 399                         task))
 400                 return;
 401         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
 402                         hdr->args.lock_context, FMODE_WRITE) == -EIO)
 403                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 404 }
 405
 406 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 407 {
 408         struct nfs_pgio_header *hdr = data;
 409
 410         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
 411             task->tk_status == 0) {
 412                 nfs41_sequence_done(task, &hdr->res.seq_res);
 413                 return;
 414         }
 415
 416         /* Note this may cause RPC to be resent */
 417         hdr->mds_ops->rpc_call_done(task, data);
 418 }
 419
 420 static void filelayout_write_count_stats(struct rpc_task *task, void *data)
 421 {
 422         struct nfs_pgio_header *hdr = data;
 423
 424         rpc_count_iostats(task, NFS_SERVER(hdr->inode)->client->cl_metrics);
 425 }
 426
 427 static void filelayout_commit_prepare(struct rpc_task *task, void *data)
 428 {
 429         struct nfs_commit_data *wdata = data;
 430
 431         nfs41_setup_sequence(wdata->ds_clp->cl_session,
 432                         &wdata->args.seq_args,
 433                         &wdata->res.seq_res,
 434                         task);
 435 }
 436
 437 static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
 438 {
 439         struct nfs_commit_data *cdata = data;
 440
 441         rpc_count_iostats(task, NFS_SERVER(cdata->inode)->client->cl_metrics);
 442 }
 443
 444 static const struct rpc_call_ops filelayout_read_call_ops = {
 445         .rpc_call_prepare = filelayout_read_prepare,
 446         .rpc_call_done = filelayout_read_call_done,
 447         .rpc_count_stats = filelayout_read_count_stats,
 448         .rpc_release = pnfs_generic_rw_release,
 449 };
 450
 451 static const struct rpc_call_ops filelayout_write_call_ops = {
 452         .rpc_call_prepare = filelayout_write_prepare,
 453         .rpc_call_done = filelayout_write_call_done,
 454         .rpc_count_stats = filelayout_write_count_stats,
 455         .rpc_release = pnfs_generic_rw_release,
 456 };
 457
 458 static const struct rpc_call_ops filelayout_commit_call_ops = {
 459         .rpc_call_prepare = filelayout_commit_prepare,
 460         .rpc_call_done = pnfs_generic_write_commit_done,
 461         .rpc_count_stats = filelayout_commit_count_stats,
 462         .rpc_release = pnfs_generic_commit_release,
 463 };
 464
 465 static enum pnfs_try_status
 466 filelayout_read_pagelist(struct nfs_pgio_header *hdr)
 467 {
 468         struct pnfs_layout_segment *lseg = hdr->lseg;
 469         struct nfs4_pnfs_ds *ds;
 470         struct rpc_clnt *ds_clnt;
 471         loff_t offset = hdr->args.offset;
 472         u32 j, idx;
 473         struct nfs_fh *fh;
 474
 475         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
 476                 __func__, hdr->inode->i_ino,
 477                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
 478
 479         /* Retrieve the correct rpc_client for the byte range */
 480         j = nfs4_fl_calc_j_index(lseg, offset);
 481         idx = nfs4_fl_calc_ds_index(lseg, j);
 482         ds = nfs4_fl_prepare_ds(lseg, idx);
 483         if (!ds)
 484                 return PNFS_NOT_ATTEMPTED;
 485
 486         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 487         if (IS_ERR(ds_clnt))
 488                 return PNFS_NOT_ATTEMPTED;
 489
 490         dprintk("%s USE DS: %s cl_count %d\n", __func__,
 491                 ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 492
 493         /* No multipath support. Use first DS */
 494         atomic_inc(&ds->ds_clp->cl_count);
 495         hdr->ds_clp = ds->ds_clp;
 496         hdr->ds_commit_idx = idx;
 497         fh = nfs4_fl_select_ds_fh(lseg, j);
 498         if (fh)
 499                 hdr->args.fh = fh;
 500
 501         hdr->args.offset = filelayout_get_dserver_offset(lseg, offset);
 502         hdr->mds_offset = offset;
 503
 504         /* Perform an asynchronous read to ds */
 505         nfs_initiate_pgio(ds_clnt, hdr, hdr->cred,
 506                           NFS_PROTO(hdr->inode), &filelayout_read_call_ops,
 507                           0, RPC_TASK_SOFTCONN);
 508         return PNFS_ATTEMPTED;
 509 }
 510
 511 /* Perform async writes. */
 512 static enum pnfs_try_status
 513 filelayout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 514 {
 515         struct pnfs_layout_segment *lseg = hdr->lseg;
 516         struct nfs4_pnfs_ds *ds;
 517         struct rpc_clnt *ds_clnt;
 518         loff_t offset = hdr->args.offset;
 519         u32 j, idx;
 520         struct nfs_fh *fh;
 521
 522         /* Retrieve the correct rpc_client for the byte range */
 523         j = nfs4_fl_calc_j_index(lseg, offset);
 524         idx = nfs4_fl_calc_ds_index(lseg, j);
 525         ds = nfs4_fl_prepare_ds(lseg, idx);
 526         if (!ds)
 527                 return PNFS_NOT_ATTEMPTED;
 528
 529         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 530         if (IS_ERR(ds_clnt))
 531                 return PNFS_NOT_ATTEMPTED;
 532
 533         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d\n",
 534                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
 535                 offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count));
 536
 537         hdr->pgio_done_cb = filelayout_write_done_cb;
 538         atomic_inc(&ds->ds_clp->cl_count);
 539         hdr->ds_clp = ds->ds_clp;
 540         hdr->ds_commit_idx = idx;
 541         fh = nfs4_fl_select_ds_fh(lseg, j);
 542         if (fh)
 543                 hdr->args.fh = fh;
 544         hdr->args.offset = filelayout_get_dserver_offset(lseg, offset);
 545
 546         /* Perform an asynchronous write */
 547         nfs_initiate_pgio(ds_clnt, hdr, hdr->cred,
 548                           NFS_PROTO(hdr->inode), &filelayout_write_call_ops,
 549                           sync, RPC_TASK_SOFTCONN);
 550         return PNFS_ATTEMPTED;
 551 }
 552
 553 /*
 554  * filelayout_check_layout()
 555  *
 556  * Make sure layout segment parameters are sane WRT the device.
 557  * At this point no generic layer initialization of the lseg has occurred,
 558  * and nothing has been added to the layout_hdr cache.
 559  *
 560  */
 561 static int
 562 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 563                         struct nfs4_filelayout_segment *fl,
 564                         struct nfs4_layoutget_res *lgr,
 565                         struct nfs4_deviceid *id,
 566                         gfp_t gfp_flags)
 567 {
 568         struct nfs4_deviceid_node *d;
 569         struct nfs4_file_layout_dsaddr *dsaddr;
 570         int status = -EINVAL;
 571
 572         dprintk("--> %s\n", __func__);
 573
 574         /* FIXME: remove this check when layout segment support is added */
 575         if (lgr->range.offset != 0 ||
 576             lgr->range.length != NFS4_MAX_UINT64) {
 577                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 578                         __func__);
 579                 goto out;
 580         }
 581
 582         if (fl->pattern_offset > lgr->range.offset) {
 583                 dprintk("%s pattern_offset %lld too large\n",
 584                                 __func__, fl->pattern_offset);
 585                 goto out;
 586         }
 587
 588         if (!fl->stripe_unit) {
 589                 dprintk("%s Invalid stripe unit (%u)\n",
 590                         __func__, fl->stripe_unit);
 591                 goto out;
 592         }
 593
 594         /* find and reference the deviceid */
 595         d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode), id,
 596                         lo->plh_lc_cred, gfp_flags);
 597         if (d == NULL)
 598                 goto out;
 599
 600         dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 601         /* Found deviceid is unavailable */
 602         if (filelayout_test_devid_unavailable(&dsaddr->id_node))
 603                 goto out_put;
 604
 605         fl->dsaddr = dsaddr;
 606
 607         if (fl->first_stripe_index >= dsaddr->stripe_count) {
 608                 dprintk("%s Bad first_stripe_index %u\n",
 609                                 __func__, fl->first_stripe_index);
 610                 goto out_put;
 611         }
 612
 613         if ((fl->stripe_type == STRIPE_SPARSE &&
 614             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 615             (fl->stripe_type == STRIPE_DENSE &&
 616             fl->num_fh != dsaddr->stripe_count)) {
 617                 dprintk("%s num_fh %u not valid for given packing\n",
 618                         __func__, fl->num_fh);
 619                 goto out_put;
 620         }
 621
 622         status = 0;
 623 out:
 624         dprintk("--> %s returns %d\n", __func__, status);
 625         return status;
 626 out_put:
 627         nfs4_fl_put_deviceid(dsaddr);
 628         goto out;
 629 }
 630
 631 static void _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 632 {
 633         int i;
 634
 635         if (fl->fh_array) {
 636                 for (i = 0; i < fl->num_fh; i++) {
 637                         if (!fl->fh_array[i])
 638                                 break;
 639                         kfree(fl->fh_array[i]);
 640                 }
 641                 kfree(fl->fh_array);
 642         }
 643         kfree(fl);
 644 }
 645
 646 static int
 647 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 648                          struct nfs4_filelayout_segment *fl,
 649                          struct nfs4_layoutget_res *lgr,
 650                          struct nfs4_deviceid *id,
 651                          gfp_t gfp_flags)
 652 {
 653         struct xdr_stream stream;
 654         struct xdr_buf buf;
 655         struct page *scratch;
 656         __be32 *p;
 657         uint32_t nfl_util;
 658         int i;
 659
 660         dprintk("%s: set_layout_map Begin\n", __func__);
 661
 662         scratch = alloc_page(gfp_flags);
 663         if (!scratch)
 664                 return -ENOMEM;
 665
 666         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
 667         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 668
 669         /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
 670          * num_fh (4) */
 671         p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
 672         if (unlikely(!p))
 673                 goto out_err;
 674
 675         memcpy(id, p, sizeof(*id));
 676         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 677         nfs4_print_deviceid(id);
 678
 679         nfl_util = be32_to_cpup(p++);
 680         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 681                 fl->commit_through_mds = 1;
 682         if (nfl_util & NFL4_UFLG_DENSE)
 683                 fl->stripe_type = STRIPE_DENSE;
 684         else
 685                 fl->stripe_type = STRIPE_SPARSE;
 686         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 687
 688         fl->first_stripe_index = be32_to_cpup(p++);
 689         p = xdr_decode_hyper(p, &fl->pattern_offset);
 690         fl->num_fh = be32_to_cpup(p++);
 691
 692         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 693                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 694                 fl->pattern_offset);
 695
 696         /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
 697          * Futher checking is done in filelayout_check_layout */
 698         if (fl->num_fh >
 699             max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
 700                 goto out_err;
 701
 702         if (fl->num_fh > 0) {
 703                 fl->fh_array = kcalloc(fl->num_fh, sizeof(fl->fh_array[0]),
 704                                        gfp_flags);
 705                 if (!fl->fh_array)
 706                         goto out_err;
 707         }
 708
 709         for (i = 0; i < fl->num_fh; i++) {
 710                 /* Do we want to use a mempool here? */
 711                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
 712                 if (!fl->fh_array[i])
 713                         goto out_err;
 714
 715                 p = xdr_inline_decode(&stream, 4);
 716                 if (unlikely(!p))
 717                         goto out_err;
 718                 fl->fh_array[i]->size = be32_to_cpup(p++);
 719                 if (sizeof(struct nfs_fh) < fl->fh_array[i]->size) {
 720                         printk(KERN_ERR "NFS: Too big fh %d received %d\n",
 721                                i, fl->fh_array[i]->size);
 722                         goto out_err;
 723                 }
 724
 725                 p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
 726                 if (unlikely(!p))
 727                         goto out_err;
 728                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 729                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 730                         fl->fh_array[i]->size);
 731         }
 732
 733         __free_page(scratch);
 734         return 0;
 735
 736 out_err:
 737         __free_page(scratch);
 738         return -EIO;
 739 }
 740
 741 static void
 742 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 743 {
 744         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 745
 746         dprintk("--> %s\n", __func__);
 747         nfs4_fl_put_deviceid(fl->dsaddr);
 748         /* This assumes a single RW lseg */
 749         if (lseg->pls_range.iomode == IOMODE_RW) {
 750                 struct nfs4_filelayout *flo;
 751
 752                 flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
 753                 flo->commit_info.nbuckets = 0;
 754                 kfree(flo->commit_info.buckets);
 755                 flo->commit_info.buckets = NULL;
 756         }
 757         _filelayout_free_lseg(fl);
 758 }
 759
 760 static int
 761 filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 762                              struct nfs_commit_info *cinfo,
 763                              gfp_t gfp_flags)
 764 {
 765         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 766         struct pnfs_commit_bucket *buckets;
 767         int size, i;
 768
 769         if (fl->commit_through_mds)
 770                 return 0;
 771
 772         size = (fl->stripe_type == STRIPE_SPARSE) ?
 773                 fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
 774
 775         if (cinfo->ds->nbuckets >= size) {
 776                 /* This assumes there is only one IOMODE_RW lseg.  What
 777                  * we really want to do is have a layout_hdr level
 778                  * dictionary of <multipath_list4, fh> keys, each
 779                  * associated with a struct list_head, populated by calls
 780                  * to filelayout_write_pagelist().
 781                  * */
 782                 return 0;
 783         }
 784
 785         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 786                           gfp_flags);
 787         if (!buckets)
 788                 return -ENOMEM;
 789         for (i = 0; i < size; i++) {
 790                 INIT_LIST_HEAD(&buckets[i].written);
 791                 INIT_LIST_HEAD(&buckets[i].committing);
 792                 /* mark direct verifier as unset */
 793                 buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW;
 794         }
 795
 796         spin_lock(cinfo->lock);
 797         if (cinfo->ds->nbuckets >= size)
 798                 goto out;
 799         for (i = 0; i < cinfo->ds->nbuckets; i++) {
 800                 list_splice(&cinfo->ds->buckets[i].written,
 801                             &buckets[i].written);
 802                 list_splice(&cinfo->ds->buckets[i].committing,
 803                             &buckets[i].committing);
 804                 buckets[i].direct_verf.committed =
 805                         cinfo->ds->buckets[i].direct_verf.committed;
 806                 buckets[i].wlseg = cinfo->ds->buckets[i].wlseg;
 807                 buckets[i].clseg = cinfo->ds->buckets[i].clseg;
 808         }
 809         swap(cinfo->ds->buckets, buckets);
 810         cinfo->ds->nbuckets = size;
 811 out:
 812         spin_unlock(cinfo->lock);
 813         kfree(buckets);
 814         return 0;
 815 }
 816
 817 static struct pnfs_layout_segment *
 818 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 819                       struct nfs4_layoutget_res *lgr,
 820                       gfp_t gfp_flags)
 821 {
 822         struct nfs4_filelayout_segment *fl;
 823         int rc;
 824         struct nfs4_deviceid id;
 825
 826         dprintk("--> %s\n", __func__);
 827         fl = kzalloc(sizeof(*fl), gfp_flags);
 828         if (!fl)
 829                 return NULL;
 830
 831         rc = filelayout_decode_layout(layoutid, fl, lgr, &id, gfp_flags);
 832         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, &id, gfp_flags)) {
 833                 _filelayout_free_lseg(fl);
 834                 return NULL;
 835         }
 836         return &fl->generic_hdr;
 837 }
 838
 839 /*
 840  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 841  *
 842  * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
 843  * of bytes (maximum @req->wb_bytes) that can be coalesced.
 844  */
 845 static size_t
 846 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 847                    struct nfs_page *req)
 848 {
 849         unsigned int size;
 850         u64 p_stripe, r_stripe;
 851         u32 stripe_offset;
 852         u64 segment_offset = pgio->pg_lseg->pls_range.offset;
 853         u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 854
 855         /* calls nfs_generic_pg_test */
 856         size = pnfs_generic_pg_test(pgio, prev, req);
 857         if (!size)
 858                 return 0;
 859
 860         /* see if req and prev are in the same stripe */
 861         if (prev) {
 862                 p_stripe = (u64)req_offset(prev) - segment_offset;
 863                 r_stripe = (u64)req_offset(req) - segment_offset;
 864                 do_div(p_stripe, stripe_unit);
 865                 do_div(r_stripe, stripe_unit);
 866
 867                 if (p_stripe != r_stripe)
 868                         return 0;
 869         }
 870
 871         /* calculate remaining bytes in the current stripe */
 872         div_u64_rem((u64)req_offset(req) - segment_offset,
 873                         stripe_unit,
 874                         &stripe_offset);
 875         WARN_ON_ONCE(stripe_offset > stripe_unit);
 876         if (stripe_offset >= stripe_unit)
 877                 return 0;
 878         return min(stripe_unit - (unsigned int)stripe_offset, size);
 879 }
 880
 881 static void
 882 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 883                         struct nfs_page *req)
 884 {
 885         if (!pgio->pg_lseg) {
 886                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 887                                            req->wb_context,
 888                                            0,
 889                                            NFS4_MAX_UINT64,
 890                                            IOMODE_READ,
 891                                            GFP_KERNEL);
 892                 if (IS_ERR(pgio->pg_lseg)) {
 893                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 894                         pgio->pg_lseg = NULL;
 895                         return;
 896                 }
 897         }
 898         /* If no lseg, fall back to read through mds */
 899         if (pgio->pg_lseg == NULL)
 900                 nfs_pageio_reset_read_mds(pgio);
 901 }
 902
 903 static void
 904 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 905                          struct nfs_page *req)
 906 {
 907         struct nfs_commit_info cinfo;
 908         int status;
 909
 910         if (!pgio->pg_lseg) {
 911                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 912                                            req->wb_context,
 913                                            0,
 914                                            NFS4_MAX_UINT64,
 915                                            IOMODE_RW,
 916                                            GFP_NOFS);
 917                 if (IS_ERR(pgio->pg_lseg)) {
 918                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 919                         pgio->pg_lseg = NULL;
 920                         return;
 921                 }
 922         }
 923
 924         /* If no lseg, fall back to write through mds */
 925         if (pgio->pg_lseg == NULL)
 926                 goto out_mds;
 927         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 928         status = filelayout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 929         if (status < 0) {
 930                 pnfs_put_lseg(pgio->pg_lseg);
 931                 pgio->pg_lseg = NULL;
 932                 goto out_mds;
 933         }
 934         return;
 935 out_mds:
 936         nfs_pageio_reset_write_mds(pgio);
 937 }
 938
 939 static const struct nfs_pageio_ops filelayout_pg_read_ops = {
 940         .pg_init = filelayout_pg_init_read,
 941         .pg_test = filelayout_pg_test,
 942         .pg_doio = pnfs_generic_pg_readpages,
 943         .pg_cleanup = pnfs_generic_pg_cleanup,
 944 };
 945
 946 static const struct nfs_pageio_ops filelayout_pg_write_ops = {
 947         .pg_init = filelayout_pg_init_write,
 948         .pg_test = filelayout_pg_test,
 949         .pg_doio = pnfs_generic_pg_writepages,
 950         .pg_cleanup = pnfs_generic_pg_cleanup,
 951 };
 952
 953 static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
 954 {
 955         if (fl->stripe_type == STRIPE_SPARSE)
 956                 return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
 957         else
 958                 return j;
 959 }
 960
 961 static void
 962 filelayout_mark_request_commit(struct nfs_page *req,
 963                                struct pnfs_layout_segment *lseg,
 964                                struct nfs_commit_info *cinfo,
 965                                u32 ds_commit_idx)
 966
 967 {
 968         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 969         u32 i, j;
 970
 971         if (fl->commit_through_mds) {
 972                 nfs_request_add_commit_list(req, &cinfo->mds->list, cinfo);
 973         } else {
 974                 /* Note that we are calling nfs4_fl_calc_j_index on each page
 975                  * that ends up being committed to a data server.  An attractive
 976                  * alternative is to add a field to nfs_write_data and nfs_page
 977                  * to store the value calculated in filelayout_write_pagelist
 978                  * and just use that here.
 979                  */
 980                 j = nfs4_fl_calc_j_index(lseg, req_offset(req));
 981                 i = select_bucket_index(fl, j);
 982                 pnfs_layout_mark_request_commit(req, lseg, cinfo, i);
 983         }
 984 }
 985
 986 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 987 {
 988         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 989
 990         if (flseg->stripe_type == STRIPE_SPARSE)
 991                 return i;
 992         else
 993                 return nfs4_fl_calc_ds_index(lseg, i);
 994 }
 995
 996 static struct nfs_fh *
 997 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 998 {
 999         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
1000
1001         if (flseg->stripe_type == STRIPE_SPARSE) {
1002                 if (flseg->num_fh == 1)
1003                         i = 0;
1004                 else if (flseg->num_fh == 0)
1005                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
1006                         return NULL;
1007         }
1008         return flseg->fh_array[i];
1009 }
1010
1011 static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
1012 {
1013         struct pnfs_layout_segment *lseg = data->lseg;
1014         struct nfs4_pnfs_ds *ds;
1015         struct rpc_clnt *ds_clnt;
1016         u32 idx;
1017         struct nfs_fh *fh;
1018
1019         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1020         ds = nfs4_fl_prepare_ds(lseg, idx);
1021         if (!ds)
1022                 goto out_err;
1023
1024         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, data->inode);
1025         if (IS_ERR(ds_clnt))
1026                 goto out_err;
1027
1028         dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
1029                 data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count));
1030         data->commit_done_cb = filelayout_commit_done_cb;
1031         atomic_inc(&ds->ds_clp->cl_count);
1032         data->ds_clp = ds->ds_clp;
1033         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1034         if (fh)
1035                 data->args.fh = fh;
1036         return nfs_initiate_commit(ds_clnt, data, NFS_PROTO(data->inode),
1037                                    &filelayout_commit_call_ops, how,
1038                                    RPC_TASK_SOFTCONN);
1039 out_err:
1040         pnfs_generic_prepare_to_resend_writes(data);
1041         pnfs_generic_commit_release(data);
1042         return -EAGAIN;
1043 }
1044
1045 /* filelayout_search_commit_reqs - Search lists in @cinfo for the head reqest
1046  *                                 for @page
1047  * @cinfo - commit info for current inode
1048  * @page - page to search for matching head request
1049  *
1050  * Returns a the head request if one is found, otherwise returns NULL.
1051  */
1052 static struct nfs_page *
1053 filelayout_search_commit_reqs(struct nfs_commit_info *cinfo, struct page *page)
1054 {
1055         struct nfs_page *freq, *t;
1056         struct pnfs_commit_bucket *b;
1057         int i;
1058
1059         /* Linearly search the commit lists for each bucket until a matching
1060          * request is found */
1061         for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
1062                 list_for_each_entry_safe(freq, t, &b->written, wb_list) {
1063                         if (freq->wb_page == page)
1064                                 return freq->wb_head;
1065                 }
1066                 list_for_each_entry_safe(freq, t, &b->committing, wb_list) {
1067                         if (freq->wb_page == page)
1068                                 return freq->wb_head;
1069                 }
1070         }
1071
1072         return NULL;
1073 }
1074
1075 static int
1076 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1077                            int how, struct nfs_commit_info *cinfo)
1078 {
1079         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1080                                             filelayout_initiate_commit);
1081 }
1082
1083 static struct nfs4_deviceid_node *
1084 filelayout_alloc_deviceid_node(struct nfs_server *server,
1085                 struct pnfs_device *pdev, gfp_t gfp_flags)
1086 {
1087         struct nfs4_file_layout_dsaddr *dsaddr;
1088
1089         dsaddr = nfs4_fl_alloc_deviceid_node(server, pdev, gfp_flags);
1090         if (!dsaddr)
1091                 return NULL;
1092         return &dsaddr->id_node;
1093 }
1094
1095 static void
1096 filelayout_free_deviceid_node(struct nfs4_deviceid_node *d)
1097 {
1098         nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
1099 }
1100
1101 static struct pnfs_layout_hdr *
1102 filelayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
1103 {
1104         struct nfs4_filelayout *flo;
1105
1106         flo = kzalloc(sizeof(*flo), gfp_flags);
1107         return flo != NULL ? &flo->generic_hdr : NULL;
1108 }
1109
1110 static void
1111 filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
1112 {
1113         kfree(FILELAYOUT_FROM_HDR(lo));
1114 }
1115
1116 static struct pnfs_ds_commit_info *
1117 filelayout_get_ds_info(struct inode *inode)
1118 {
1119         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1120
1121         if (layout == NULL)
1122                 return NULL;
1123         else
1124                 return &FILELAYOUT_FROM_HDR(layout)->commit_info;
1125 }
1126
1127 static struct pnfs_layoutdriver_type filelayout_type = {
1128         .id                     = LAYOUT_NFSV4_1_FILES,
1129         .name                   = "LAYOUT_NFSV4_1_FILES",
1130         .owner                  = THIS_MODULE,
1131         .alloc_layout_hdr       = filelayout_alloc_layout_hdr,
1132         .free_layout_hdr        = filelayout_free_layout_hdr,
1133         .alloc_lseg             = filelayout_alloc_lseg,
1134         .free_lseg              = filelayout_free_lseg,
1135         .pg_read_ops            = &filelayout_pg_read_ops,
1136         .pg_write_ops           = &filelayout_pg_write_ops,
1137         .get_ds_info            = &filelayout_get_ds_info,
1138         .mark_request_commit    = filelayout_mark_request_commit,
1139         .clear_request_commit   = pnfs_generic_clear_request_commit,
1140         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
1141         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
1142         .search_commit_reqs     = filelayout_search_commit_reqs,
1143         .commit_pagelist        = filelayout_commit_pagelist,
1144         .read_pagelist          = filelayout_read_pagelist,
1145         .write_pagelist         = filelayout_write_pagelist,
1146         .alloc_deviceid_node    = filelayout_alloc_deviceid_node,
1147         .free_deviceid_node     = filelayout_free_deviceid_node,
1148         .sync                   = pnfs_nfs_generic_sync,
1149 };
1150
1151 static int __init nfs4filelayout_init(void)
1152 {
1153         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
1154                __func__);
1155         return pnfs_register_layoutdriver(&filelayout_type);
1156 }
1157
1158 static void __exit nfs4filelayout_exit(void)
1159 {
1160         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
1161                __func__);
1162         pnfs_unregister_layoutdriver(&filelayout_type);
1163 }
1164
1165 MODULE_ALIAS("nfs-layouttype4-1");
1166
1167 module_init(nfs4filelayout_init);
1168 module_exit(nfs4filelayout_exit);