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 static const struct pnfs_commit_ops filelayout_commit_ops;
  53
  54 static loff_t
  55 filelayout_get_dense_offset(struct nfs4_filelayout_segment *flseg,
  56                             loff_t offset)
  57 {
  58         u32 stripe_width = flseg->stripe_unit * flseg->dsaddr->stripe_count;
  59         u64 stripe_no;
  60         u32 rem;
  61
  62         offset -= flseg->pattern_offset;
  63         stripe_no = div_u64(offset, stripe_width);
  64         div_u64_rem(offset, flseg->stripe_unit, &rem);
  65
  66         return stripe_no * flseg->stripe_unit + rem;
  67 }
  68
  69 /* This function is used by the layout driver to calculate the
  70  * offset of the file on the dserver based on whether the
  71  * layout type is STRIPE_DENSE or STRIPE_SPARSE
  72  */
  73 static loff_t
  74 filelayout_get_dserver_offset(struct pnfs_layout_segment *lseg, loff_t offset)
  75 {
  76         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
  77
  78         switch (flseg->stripe_type) {
  79         case STRIPE_SPARSE:
  80                 return offset;
  81
  82         case STRIPE_DENSE:
  83                 return filelayout_get_dense_offset(flseg, offset);
  84         }
  85
  86         BUG();
  87 }
  88
  89 static void filelayout_reset_write(struct nfs_pgio_header *hdr)
  90 {
  91         struct rpc_task *task = &hdr->task;
  92
  93         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
  94                 dprintk("%s Reset task %5u for i/o through MDS "
  95                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
  96                         hdr->task.tk_pid,
  97                         hdr->inode->i_sb->s_id,
  98                         (unsigned long long)NFS_FILEID(hdr->inode),
  99                         hdr->args.count,
 100                         (unsigned long long)hdr->args.offset);
 101
 102                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
 103         }
 104 }
 105
 106 static void filelayout_reset_read(struct nfs_pgio_header *hdr)
 107 {
 108         struct rpc_task *task = &hdr->task;
 109
 110         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 111                 dprintk("%s Reset task %5u for i/o through MDS "
 112                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 113                         hdr->task.tk_pid,
 114                         hdr->inode->i_sb->s_id,
 115                         (unsigned long long)NFS_FILEID(hdr->inode),
 116                         hdr->args.count,
 117                         (unsigned long long)hdr->args.offset);
 118
 119                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
 120         }
 121 }
 122
 123 static int filelayout_async_handle_error(struct rpc_task *task,
 124                                          struct nfs4_state *state,
 125                                          struct nfs_client *clp,
 126                                          struct pnfs_layout_segment *lseg)
 127 {
 128         struct pnfs_layout_hdr *lo = lseg->pls_layout;
 129         struct inode *inode = lo->plh_inode;
 130         struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
 131         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 132
 133         if (task->tk_status >= 0)
 134                 return 0;
 135
 136         switch (task->tk_status) {
 137         /* DS session errors */
 138         case -NFS4ERR_BADSESSION:
 139         case -NFS4ERR_BADSLOT:
 140         case -NFS4ERR_BAD_HIGH_SLOT:
 141         case -NFS4ERR_DEADSESSION:
 142         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 143         case -NFS4ERR_SEQ_FALSE_RETRY:
 144         case -NFS4ERR_SEQ_MISORDERED:
 145                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 146                         "flags 0x%x\n", __func__, task->tk_status,
 147                         clp->cl_exchange_flags);
 148                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
 149                 break;
 150         case -NFS4ERR_DELAY:
 151         case -NFS4ERR_GRACE:
 152                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
 153                 break;
 154         case -NFS4ERR_RETRY_UNCACHED_REP:
 155                 break;
 156         /* Invalidate Layout errors */
 157         case -NFS4ERR_ACCESS:
 158         case -NFS4ERR_PNFS_NO_LAYOUT:
 159         case -ESTALE:           /* mapped NFS4ERR_STALE */
 160         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
 161         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
 162         case -NFS4ERR_FHEXPIRED:
 163         case -NFS4ERR_WRONG_TYPE:
 164                 dprintk("%s Invalid layout error %d\n", __func__,
 165                         task->tk_status);
 166                 /*
 167                  * Destroy layout so new i/o will get a new layout.
 168                  * Layout will not be destroyed until all current lseg
 169                  * references are put. Mark layout as invalid to resend failed
 170                  * i/o and all i/o waiting on the slot table to the MDS until
 171                  * layout is destroyed and a new valid layout is obtained.
 172                  */
 173                 pnfs_destroy_layout(NFS_I(inode));
 174                 rpc_wake_up(&tbl->slot_tbl_waitq);
 175                 goto reset;
 176         /* RPC connection errors */
 177         case -ECONNREFUSED:
 178         case -EHOSTDOWN:
 179         case -EHOSTUNREACH:
 180         case -ENETUNREACH:
 181         case -EIO:
 182         case -ETIMEDOUT:
 183         case -EPIPE:
 184         case -EPROTO:
 185         case -ENODEV:
 186                 dprintk("%s DS connection error %d\n", __func__,
 187                         task->tk_status);
 188                 nfs4_mark_deviceid_unavailable(devid);
 189                 pnfs_error_mark_layout_for_return(inode, lseg);
 190                 pnfs_set_lo_fail(lseg);
 191                 rpc_wake_up(&tbl->slot_tbl_waitq);
 192                 fallthrough;
 193         default:
 194 reset:
 195                 dprintk("%s Retry through MDS. Error %d\n", __func__,
 196                         task->tk_status);
 197                 return -NFS4ERR_RESET_TO_MDS;
 198         }
 199         task->tk_status = 0;
 200         return -EAGAIN;
 201 }
 202
 203 /* NFS_PROTO call done callback routines */
 204
 205 static int filelayout_read_done_cb(struct rpc_task *task,
 206                                 struct nfs_pgio_header *hdr)
 207 {
 208         int err;
 209
 210         trace_nfs4_pnfs_read(hdr, task->tk_status);
 211         err = filelayout_async_handle_error(task, hdr->args.context->state,
 212                                             hdr->ds_clp, hdr->lseg);
 213
 214         switch (err) {
 215         case -NFS4ERR_RESET_TO_MDS:
 216                 filelayout_reset_read(hdr);
 217                 return task->tk_status;
 218         case -EAGAIN:
 219                 rpc_restart_call_prepare(task);
 220                 return -EAGAIN;
 221         }
 222
 223         return 0;
 224 }
 225
 226 /*
 227  * We reference the rpc_cred of the first WRITE that triggers the need for
 228  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
 229  * rfc5661 is not clear about which credential should be used.
 230  */
 231 static void
 232 filelayout_set_layoutcommit(struct nfs_pgio_header *hdr)
 233 {
 234         loff_t end_offs = 0;
 235
 236         if (FILELAYOUT_LSEG(hdr->lseg)->commit_through_mds ||
 237             hdr->res.verf->committed == NFS_FILE_SYNC)
 238                 return;
 239         if (hdr->res.verf->committed == NFS_DATA_SYNC)
 240                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
 241
 242         /* Note: if the write is unstable, don't set end_offs until commit */
 243         pnfs_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
 244         dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
 245                 (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
 246 }
 247
 248 bool
 249 filelayout_test_devid_unavailable(struct nfs4_deviceid_node *node)
 250 {
 251         return filelayout_test_devid_invalid(node) ||
 252                 nfs4_test_deviceid_unavailable(node);
 253 }
 254
 255 static bool
 256 filelayout_reset_to_mds(struct pnfs_layout_segment *lseg)
 257 {
 258         struct nfs4_deviceid_node *node = FILELAYOUT_DEVID_NODE(lseg);
 259
 260         return filelayout_test_devid_unavailable(node);
 261 }
 262
 263 /*
 264  * Call ops for the async read/write cases
 265  * In the case of dense layouts, the offset needs to be reset to its
 266  * original value.
 267  */
 268 static void filelayout_read_prepare(struct rpc_task *task, void *data)
 269 {
 270         struct nfs_pgio_header *hdr = data;
 271
 272         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
 273                 rpc_exit(task, -EIO);
 274                 return;
 275         }
 276         if (filelayout_reset_to_mds(hdr->lseg)) {
 277                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 278                 filelayout_reset_read(hdr);
 279                 rpc_exit(task, 0);
 280                 return;
 281         }
 282         hdr->pgio_done_cb = filelayout_read_done_cb;
 283
 284         if (nfs4_setup_sequence(hdr->ds_clp,
 285                         &hdr->args.seq_args,
 286                         &hdr->res.seq_res,
 287                         task))
 288                 return;
 289         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
 290                         hdr->args.lock_context, FMODE_READ) == -EIO)
 291                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 292 }
 293
 294 static void filelayout_read_call_done(struct rpc_task *task, void *data)
 295 {
 296         struct nfs_pgio_header *hdr = data;
 297
 298         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
 299             task->tk_status == 0) {
 300                 nfs41_sequence_done(task, &hdr->res.seq_res);
 301                 return;
 302         }
 303
 304         /* Note this may cause RPC to be resent */
 305         hdr->mds_ops->rpc_call_done(task, data);
 306 }
 307
 308 static void filelayout_read_count_stats(struct rpc_task *task, void *data)
 309 {
 310         struct nfs_pgio_header *hdr = data;
 311
 312         rpc_count_iostats(task, NFS_SERVER(hdr->inode)->client->cl_metrics);
 313 }
 314
 315 static int filelayout_write_done_cb(struct rpc_task *task,
 316                                 struct nfs_pgio_header *hdr)
 317 {
 318         int err;
 319
 320         trace_nfs4_pnfs_write(hdr, task->tk_status);
 321         err = filelayout_async_handle_error(task, hdr->args.context->state,
 322                                             hdr->ds_clp, hdr->lseg);
 323
 324         switch (err) {
 325         case -NFS4ERR_RESET_TO_MDS:
 326                 filelayout_reset_write(hdr);
 327                 return task->tk_status;
 328         case -EAGAIN:
 329                 rpc_restart_call_prepare(task);
 330                 return -EAGAIN;
 331         }
 332
 333         filelayout_set_layoutcommit(hdr);
 334
 335         /* zero out the fattr */
 336         hdr->fattr.valid = 0;
 337         if (task->tk_status >= 0)
 338                 nfs_writeback_update_inode(hdr);
 339
 340         return 0;
 341 }
 342
 343 static int filelayout_commit_done_cb(struct rpc_task *task,
 344                                      struct nfs_commit_data *data)
 345 {
 346         int err;
 347
 348         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
 349         err = filelayout_async_handle_error(task, NULL, data->ds_clp,
 350                                             data->lseg);
 351
 352         switch (err) {
 353         case -NFS4ERR_RESET_TO_MDS:
 354                 pnfs_generic_prepare_to_resend_writes(data);
 355                 return -EAGAIN;
 356         case -EAGAIN:
 357                 rpc_restart_call_prepare(task);
 358                 return -EAGAIN;
 359         }
 360
 361         pnfs_set_layoutcommit(data->inode, data->lseg, data->lwb);
 362
 363         return 0;
 364 }
 365
 366 static void filelayout_write_prepare(struct rpc_task *task, void *data)
 367 {
 368         struct nfs_pgio_header *hdr = data;
 369
 370         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
 371                 rpc_exit(task, -EIO);
 372                 return;
 373         }
 374         if (filelayout_reset_to_mds(hdr->lseg)) {
 375                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
 376                 filelayout_reset_write(hdr);
 377                 rpc_exit(task, 0);
 378                 return;
 379         }
 380         if (nfs4_setup_sequence(hdr->ds_clp,
 381                         &hdr->args.seq_args,
 382                         &hdr->res.seq_res,
 383                         task))
 384                 return;
 385         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
 386                         hdr->args.lock_context, FMODE_WRITE) == -EIO)
 387                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
 388 }
 389
 390 static void filelayout_write_call_done(struct rpc_task *task, void *data)
 391 {
 392         struct nfs_pgio_header *hdr = data;
 393
 394         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
 395             task->tk_status == 0) {
 396                 nfs41_sequence_done(task, &hdr->res.seq_res);
 397                 return;
 398         }
 399
 400         /* Note this may cause RPC to be resent */
 401         hdr->mds_ops->rpc_call_done(task, data);
 402 }
 403
 404 static void filelayout_write_count_stats(struct rpc_task *task, void *data)
 405 {
 406         struct nfs_pgio_header *hdr = data;
 407
 408         rpc_count_iostats(task, NFS_SERVER(hdr->inode)->client->cl_metrics);
 409 }
 410
 411 static void filelayout_commit_prepare(struct rpc_task *task, void *data)
 412 {
 413         struct nfs_commit_data *wdata = data;
 414
 415         nfs4_setup_sequence(wdata->ds_clp,
 416                         &wdata->args.seq_args,
 417                         &wdata->res.seq_res,
 418                         task);
 419 }
 420
 421 static void filelayout_commit_count_stats(struct rpc_task *task, void *data)
 422 {
 423         struct nfs_commit_data *cdata = data;
 424
 425         rpc_count_iostats(task, NFS_SERVER(cdata->inode)->client->cl_metrics);
 426 }
 427
 428 static const struct rpc_call_ops filelayout_read_call_ops = {
 429         .rpc_call_prepare = filelayout_read_prepare,
 430         .rpc_call_done = filelayout_read_call_done,
 431         .rpc_count_stats = filelayout_read_count_stats,
 432         .rpc_release = pnfs_generic_rw_release,
 433 };
 434
 435 static const struct rpc_call_ops filelayout_write_call_ops = {
 436         .rpc_call_prepare = filelayout_write_prepare,
 437         .rpc_call_done = filelayout_write_call_done,
 438         .rpc_count_stats = filelayout_write_count_stats,
 439         .rpc_release = pnfs_generic_rw_release,
 440 };
 441
 442 static const struct rpc_call_ops filelayout_commit_call_ops = {
 443         .rpc_call_prepare = filelayout_commit_prepare,
 444         .rpc_call_done = pnfs_generic_write_commit_done,
 445         .rpc_count_stats = filelayout_commit_count_stats,
 446         .rpc_release = pnfs_generic_commit_release,
 447 };
 448
 449 static enum pnfs_try_status
 450 filelayout_read_pagelist(struct nfs_pgio_header *hdr)
 451 {
 452         struct pnfs_layout_segment *lseg = hdr->lseg;
 453         struct nfs4_pnfs_ds *ds;
 454         struct rpc_clnt *ds_clnt;
 455         loff_t offset = hdr->args.offset;
 456         u32 j, idx;
 457         struct nfs_fh *fh;
 458
 459         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
 460                 __func__, hdr->inode->i_ino,
 461                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
 462
 463         /* Retrieve the correct rpc_client for the byte range */
 464         j = nfs4_fl_calc_j_index(lseg, offset);
 465         idx = nfs4_fl_calc_ds_index(lseg, j);
 466         ds = nfs4_fl_prepare_ds(lseg, idx);
 467         if (!ds)
 468                 return PNFS_NOT_ATTEMPTED;
 469
 470         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 471         if (IS_ERR(ds_clnt))
 472                 return PNFS_NOT_ATTEMPTED;
 473
 474         dprintk("%s USE DS: %s cl_count %d\n", __func__,
 475                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count));
 476
 477         /* No multipath support. Use first DS */
 478         refcount_inc(&ds->ds_clp->cl_count);
 479         hdr->ds_clp = ds->ds_clp;
 480         hdr->ds_commit_idx = idx;
 481         fh = nfs4_fl_select_ds_fh(lseg, j);
 482         if (fh)
 483                 hdr->args.fh = fh;
 484
 485         hdr->args.offset = filelayout_get_dserver_offset(lseg, offset);
 486         hdr->mds_offset = offset;
 487
 488         /* Perform an asynchronous read to ds */
 489         nfs_initiate_pgio(ds_clnt, hdr, hdr->cred,
 490                           NFS_PROTO(hdr->inode), &filelayout_read_call_ops,
 491                           0, RPC_TASK_SOFTCONN);
 492         return PNFS_ATTEMPTED;
 493 }
 494
 495 /* Perform async writes. */
 496 static enum pnfs_try_status
 497 filelayout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
 498 {
 499         struct pnfs_layout_segment *lseg = hdr->lseg;
 500         struct nfs4_pnfs_ds *ds;
 501         struct rpc_clnt *ds_clnt;
 502         loff_t offset = hdr->args.offset;
 503         u32 j, idx;
 504         struct nfs_fh *fh;
 505
 506         /* Retrieve the correct rpc_client for the byte range */
 507         j = nfs4_fl_calc_j_index(lseg, offset);
 508         idx = nfs4_fl_calc_ds_index(lseg, j);
 509         ds = nfs4_fl_prepare_ds(lseg, idx);
 510         if (!ds)
 511                 return PNFS_NOT_ATTEMPTED;
 512
 513         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, hdr->inode);
 514         if (IS_ERR(ds_clnt))
 515                 return PNFS_NOT_ATTEMPTED;
 516
 517         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d\n",
 518                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
 519                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count));
 520
 521         hdr->pgio_done_cb = filelayout_write_done_cb;
 522         refcount_inc(&ds->ds_clp->cl_count);
 523         hdr->ds_clp = ds->ds_clp;
 524         hdr->ds_commit_idx = idx;
 525         fh = nfs4_fl_select_ds_fh(lseg, j);
 526         if (fh)
 527                 hdr->args.fh = fh;
 528         hdr->args.offset = filelayout_get_dserver_offset(lseg, offset);
 529
 530         /* Perform an asynchronous write */
 531         nfs_initiate_pgio(ds_clnt, hdr, hdr->cred,
 532                           NFS_PROTO(hdr->inode), &filelayout_write_call_ops,
 533                           sync, RPC_TASK_SOFTCONN);
 534         return PNFS_ATTEMPTED;
 535 }
 536
 537 static int
 538 filelayout_check_deviceid(struct pnfs_layout_hdr *lo,
 539                           struct nfs4_filelayout_segment *fl,
 540                           gfp_t gfp_flags)
 541 {
 542         struct nfs4_deviceid_node *d;
 543         struct nfs4_file_layout_dsaddr *dsaddr;
 544         int status = -EINVAL;
 545
 546         /* Is the deviceid already set? If so, we're good. */
 547         if (fl->dsaddr != NULL)
 548                 return 0;
 549
 550         /* find and reference the deviceid */
 551         d = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode), &fl->deviceid,
 552                         lo->plh_lc_cred, gfp_flags);
 553         if (d == NULL)
 554                 goto out;
 555
 556         dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 557         /* Found deviceid is unavailable */
 558         if (filelayout_test_devid_unavailable(&dsaddr->id_node))
 559                 goto out_put;
 560
 561         if (fl->first_stripe_index >= dsaddr->stripe_count) {
 562                 dprintk("%s Bad first_stripe_index %u\n",
 563                                 __func__, fl->first_stripe_index);
 564                 goto out_put;
 565         }
 566
 567         if ((fl->stripe_type == STRIPE_SPARSE &&
 568             fl->num_fh > 1 && fl->num_fh != dsaddr->ds_num) ||
 569             (fl->stripe_type == STRIPE_DENSE &&
 570             fl->num_fh != dsaddr->stripe_count)) {
 571                 dprintk("%s num_fh %u not valid for given packing\n",
 572                         __func__, fl->num_fh);
 573                 goto out_put;
 574         }
 575         status = 0;
 576
 577         /*
 578          * Atomic compare and xchange to ensure we don't scribble
 579          * over a non-NULL pointer.
 580          */
 581         if (cmpxchg(&fl->dsaddr, NULL, dsaddr) != NULL)
 582                 goto out_put;
 583 out:
 584         return status;
 585 out_put:
 586         nfs4_fl_put_deviceid(dsaddr);
 587         goto out;
 588 }
 589
 590 /*
 591  * filelayout_check_layout()
 592  *
 593  * Make sure layout segment parameters are sane WRT the device.
 594  * At this point no generic layer initialization of the lseg has occurred,
 595  * and nothing has been added to the layout_hdr cache.
 596  *
 597  */
 598 static int
 599 filelayout_check_layout(struct pnfs_layout_hdr *lo,
 600                         struct nfs4_filelayout_segment *fl,
 601                         struct nfs4_layoutget_res *lgr,
 602                         gfp_t gfp_flags)
 603 {
 604         int status = -EINVAL;
 605
 606         dprintk("--> %s\n", __func__);
 607
 608         /* FIXME: remove this check when layout segment support is added */
 609         if (lgr->range.offset != 0 ||
 610             lgr->range.length != NFS4_MAX_UINT64) {
 611                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 612                         __func__);
 613                 goto out;
 614         }
 615
 616         if (fl->pattern_offset > lgr->range.offset) {
 617                 dprintk("%s pattern_offset %lld too large\n",
 618                                 __func__, fl->pattern_offset);
 619                 goto out;
 620         }
 621
 622         if (!fl->stripe_unit) {
 623                 dprintk("%s Invalid stripe unit (%u)\n",
 624                         __func__, fl->stripe_unit);
 625                 goto out;
 626         }
 627
 628         status = 0;
 629 out:
 630         dprintk("--> %s returns %d\n", __func__, status);
 631         return status;
 632 }
 633
 634 static void _filelayout_free_lseg(struct nfs4_filelayout_segment *fl)
 635 {
 636         int i;
 637
 638         if (fl->fh_array) {
 639                 for (i = 0; i < fl->num_fh; i++) {
 640                         if (!fl->fh_array[i])
 641                                 break;
 642                         kfree(fl->fh_array[i]);
 643                 }
 644                 kfree(fl->fh_array);
 645         }
 646         kfree(fl);
 647 }
 648
 649 static int
 650 filelayout_decode_layout(struct pnfs_layout_hdr *flo,
 651                          struct nfs4_filelayout_segment *fl,
 652                          struct nfs4_layoutget_res *lgr,
 653                          gfp_t gfp_flags)
 654 {
 655         struct xdr_stream stream;
 656         struct xdr_buf buf;
 657         struct page *scratch;
 658         __be32 *p;
 659         uint32_t nfl_util;
 660         int i;
 661
 662         dprintk("%s: set_layout_map Begin\n", __func__);
 663
 664         scratch = alloc_page(gfp_flags);
 665         if (!scratch)
 666                 return -ENOMEM;
 667
 668         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages, lgr->layoutp->len);
 669         xdr_set_scratch_page(&stream, scratch);
 670
 671         /* 20 = ufl_util (4), first_stripe_index (4), pattern_offset (8),
 672          * num_fh (4) */
 673         p = xdr_inline_decode(&stream, NFS4_DEVICEID4_SIZE + 20);
 674         if (unlikely(!p))
 675                 goto out_err;
 676
 677         memcpy(&fl->deviceid, p, sizeof(fl->deviceid));
 678         p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 679         nfs4_print_deviceid(&fl->deviceid);
 680
 681         nfl_util = be32_to_cpup(p++);
 682         if (nfl_util & NFL4_UFLG_COMMIT_THRU_MDS)
 683                 fl->commit_through_mds = 1;
 684         if (nfl_util & NFL4_UFLG_DENSE)
 685                 fl->stripe_type = STRIPE_DENSE;
 686         else
 687                 fl->stripe_type = STRIPE_SPARSE;
 688         fl->stripe_unit = nfl_util & ~NFL4_UFLG_MASK;
 689
 690         fl->first_stripe_index = be32_to_cpup(p++);
 691         p = xdr_decode_hyper(p, &fl->pattern_offset);
 692         fl->num_fh = be32_to_cpup(p++);
 693
 694         dprintk("%s: nfl_util 0x%X num_fh %u fsi %u po %llu\n",
 695                 __func__, nfl_util, fl->num_fh, fl->first_stripe_index,
 696                 fl->pattern_offset);
 697
 698         /* Note that a zero value for num_fh is legal for STRIPE_SPARSE.
 699          * Futher checking is done in filelayout_check_layout */
 700         if (fl->num_fh >
 701             max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
 702                 goto out_err;
 703
 704         if (fl->num_fh > 0) {
 705                 fl->fh_array = kcalloc(fl->num_fh, sizeof(fl->fh_array[0]),
 706                                        gfp_flags);
 707                 if (!fl->fh_array)
 708                         goto out_err;
 709         }
 710
 711         for (i = 0; i < fl->num_fh; i++) {
 712                 /* Do we want to use a mempool here? */
 713                 fl->fh_array[i] = kmalloc(sizeof(struct nfs_fh), gfp_flags);
 714                 if (!fl->fh_array[i])
 715                         goto out_err;
 716
 717                 p = xdr_inline_decode(&stream, 4);
 718                 if (unlikely(!p))
 719                         goto out_err;
 720                 fl->fh_array[i]->size = be32_to_cpup(p++);
 721                 if (fl->fh_array[i]->size > NFS_MAXFHSIZE) {
 722                         printk(KERN_ERR "NFS: Too big fh %d received %d\n",
 723                                i, fl->fh_array[i]->size);
 724                         goto out_err;
 725                 }
 726
 727                 p = xdr_inline_decode(&stream, fl->fh_array[i]->size);
 728                 if (unlikely(!p))
 729                         goto out_err;
 730                 memcpy(fl->fh_array[i]->data, p, fl->fh_array[i]->size);
 731                 dprintk("DEBUG: %s: fh len %d\n", __func__,
 732                         fl->fh_array[i]->size);
 733         }
 734
 735         __free_page(scratch);
 736         return 0;
 737
 738 out_err:
 739         __free_page(scratch);
 740         return -EIO;
 741 }
 742
 743 static void
 744 filelayout_free_lseg(struct pnfs_layout_segment *lseg)
 745 {
 746         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 747
 748         dprintk("--> %s\n", __func__);
 749         if (fl->dsaddr != NULL)
 750                 nfs4_fl_put_deviceid(fl->dsaddr);
 751         /* This assumes a single RW lseg */
 752         if (lseg->pls_range.iomode == IOMODE_RW) {
 753                 struct nfs4_filelayout *flo;
 754                 struct inode *inode;
 755
 756                 flo = FILELAYOUT_FROM_HDR(lseg->pls_layout);
 757                 inode = flo->generic_hdr.plh_inode;
 758                 spin_lock(&inode->i_lock);
 759                 pnfs_generic_ds_cinfo_release_lseg(&flo->commit_info, lseg);
 760                 spin_unlock(&inode->i_lock);
 761         }
 762         _filelayout_free_lseg(fl);
 763 }
 764
 765 static struct pnfs_layout_segment *
 766 filelayout_alloc_lseg(struct pnfs_layout_hdr *layoutid,
 767                       struct nfs4_layoutget_res *lgr,
 768                       gfp_t gfp_flags)
 769 {
 770         struct nfs4_filelayout_segment *fl;
 771         int rc;
 772
 773         dprintk("--> %s\n", __func__);
 774         fl = kzalloc(sizeof(*fl), gfp_flags);
 775         if (!fl)
 776                 return NULL;
 777
 778         rc = filelayout_decode_layout(layoutid, fl, lgr, gfp_flags);
 779         if (rc != 0 || filelayout_check_layout(layoutid, fl, lgr, gfp_flags)) {
 780                 _filelayout_free_lseg(fl);
 781                 return NULL;
 782         }
 783         return &fl->generic_hdr;
 784 }
 785
 786 static bool
 787 filelayout_lseg_is_striped(const struct nfs4_filelayout_segment *flseg)
 788 {
 789         return flseg->num_fh > 1;
 790 }
 791
 792 /*
 793  * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
 794  *
 795  * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
 796  * of bytes (maximum @req->wb_bytes) that can be coalesced.
 797  */
 798 static size_t
 799 filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
 800                    struct nfs_page *req)
 801 {
 802         unsigned int size;
 803         u64 p_stripe, r_stripe;
 804         u32 stripe_offset;
 805         u64 segment_offset = pgio->pg_lseg->pls_range.offset;
 806         u32 stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
 807
 808         /* calls nfs_generic_pg_test */
 809         size = pnfs_generic_pg_test(pgio, prev, req);
 810         if (!size)
 811                 return 0;
 812         else if (!filelayout_lseg_is_striped(FILELAYOUT_LSEG(pgio->pg_lseg)))
 813                 return size;
 814
 815         /* see if req and prev are in the same stripe */
 816         if (prev) {
 817                 p_stripe = (u64)req_offset(prev) - segment_offset;
 818                 r_stripe = (u64)req_offset(req) - segment_offset;
 819                 do_div(p_stripe, stripe_unit);
 820                 do_div(r_stripe, stripe_unit);
 821
 822                 if (p_stripe != r_stripe)
 823                         return 0;
 824         }
 825
 826         /* calculate remaining bytes in the current stripe */
 827         div_u64_rem((u64)req_offset(req) - segment_offset,
 828                         stripe_unit,
 829                         &stripe_offset);
 830         WARN_ON_ONCE(stripe_offset > stripe_unit);
 831         if (stripe_offset >= stripe_unit)
 832                 return 0;
 833         return min(stripe_unit - (unsigned int)stripe_offset, size);
 834 }
 835
 836 static struct pnfs_layout_segment *
 837 fl_pnfs_update_layout(struct inode *ino,
 838                       struct nfs_open_context *ctx,
 839                       loff_t pos,
 840                       u64 count,
 841                       enum pnfs_iomode iomode,
 842                       bool strict_iomode,
 843                       gfp_t gfp_flags)
 844 {
 845         struct pnfs_layout_segment *lseg = NULL;
 846         struct pnfs_layout_hdr *lo;
 847         struct nfs4_filelayout_segment *fl;
 848         int status;
 849
 850         lseg = pnfs_update_layout(ino, ctx, pos, count, iomode, strict_iomode,
 851                                   gfp_flags);
 852         if (IS_ERR(lseg)) {
 853                 /* Fall back to MDS on recoverable errors */
 854                 if (!nfs_error_is_fatal_on_server(PTR_ERR(lseg)))
 855                         lseg = NULL;
 856                 goto out;
 857         } else if (!lseg)
 858                 goto out;
 859
 860         lo = NFS_I(ino)->layout;
 861         fl = FILELAYOUT_LSEG(lseg);
 862
 863         status = filelayout_check_deviceid(lo, fl, gfp_flags);
 864         if (status) {
 865                 pnfs_put_lseg(lseg);
 866                 lseg = NULL;
 867         }
 868 out:
 869         return lseg;
 870 }
 871
 872 static void
 873 filelayout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 874                         struct nfs_page *req)
 875 {
 876         pnfs_generic_pg_check_layout(pgio);
 877         if (!pgio->pg_lseg) {
 878                 pgio->pg_lseg = fl_pnfs_update_layout(pgio->pg_inode,
 879                                                       nfs_req_openctx(req),
 880                                                       0,
 881                                                       NFS4_MAX_UINT64,
 882                                                       IOMODE_READ,
 883                                                       false,
 884                                                       GFP_KERNEL);
 885                 if (IS_ERR(pgio->pg_lseg)) {
 886                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 887                         pgio->pg_lseg = NULL;
 888                         return;
 889                 }
 890         }
 891         /* If no lseg, fall back to read through mds */
 892         if (pgio->pg_lseg == NULL)
 893                 nfs_pageio_reset_read_mds(pgio);
 894 }
 895
 896 static void
 897 filelayout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 898                          struct nfs_page *req)
 899 {
 900         pnfs_generic_pg_check_layout(pgio);
 901         if (!pgio->pg_lseg) {
 902                 pgio->pg_lseg = fl_pnfs_update_layout(pgio->pg_inode,
 903                                                       nfs_req_openctx(req),
 904                                                       0,
 905                                                       NFS4_MAX_UINT64,
 906                                                       IOMODE_RW,
 907                                                       false,
 908                                                       GFP_NOFS);
 909                 if (IS_ERR(pgio->pg_lseg)) {
 910                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 911                         pgio->pg_lseg = NULL;
 912                         return;
 913                 }
 914         }
 915
 916         /* If no lseg, fall back to write through mds */
 917         if (pgio->pg_lseg == NULL)
 918                 nfs_pageio_reset_write_mds(pgio);
 919 }
 920
 921 static const struct nfs_pageio_ops filelayout_pg_read_ops = {
 922         .pg_init = filelayout_pg_init_read,
 923         .pg_test = filelayout_pg_test,
 924         .pg_doio = pnfs_generic_pg_readpages,
 925         .pg_cleanup = pnfs_generic_pg_cleanup,
 926 };
 927
 928 static const struct nfs_pageio_ops filelayout_pg_write_ops = {
 929         .pg_init = filelayout_pg_init_write,
 930         .pg_test = filelayout_pg_test,
 931         .pg_doio = pnfs_generic_pg_writepages,
 932         .pg_cleanup = pnfs_generic_pg_cleanup,
 933 };
 934
 935 static u32 select_bucket_index(struct nfs4_filelayout_segment *fl, u32 j)
 936 {
 937         if (fl->stripe_type == STRIPE_SPARSE)
 938                 return nfs4_fl_calc_ds_index(&fl->generic_hdr, j);
 939         else
 940                 return j;
 941 }
 942
 943 static void
 944 filelayout_mark_request_commit(struct nfs_page *req,
 945                                struct pnfs_layout_segment *lseg,
 946                                struct nfs_commit_info *cinfo,
 947                                u32 ds_commit_idx)
 948
 949 {
 950         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
 951         u32 i, j;
 952
 953         if (fl->commit_through_mds) {
 954                 nfs_request_add_commit_list(req, cinfo);
 955         } else {
 956                 /* Note that we are calling nfs4_fl_calc_j_index on each page
 957                  * that ends up being committed to a data server.  An attractive
 958                  * alternative is to add a field to nfs_write_data and nfs_page
 959                  * to store the value calculated in filelayout_write_pagelist
 960                  * and just use that here.
 961                  */
 962                 j = nfs4_fl_calc_j_index(lseg, req_offset(req));
 963                 i = select_bucket_index(fl, j);
 964                 pnfs_layout_mark_request_commit(req, lseg, cinfo, i);
 965         }
 966 }
 967
 968 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 969 {
 970         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 971
 972         if (flseg->stripe_type == STRIPE_SPARSE)
 973                 return i;
 974         else
 975                 return nfs4_fl_calc_ds_index(lseg, i);
 976 }
 977
 978 static struct nfs_fh *
 979 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
 980 {
 981         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 982
 983         if (flseg->stripe_type == STRIPE_SPARSE) {
 984                 if (flseg->num_fh == 1)
 985                         i = 0;
 986                 else if (flseg->num_fh == 0)
 987                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
 988                         return NULL;
 989         }
 990         return flseg->fh_array[i];
 991 }
 992
 993 static int filelayout_initiate_commit(struct nfs_commit_data *data, int how)
 994 {
 995         struct pnfs_layout_segment *lseg = data->lseg;
 996         struct nfs4_pnfs_ds *ds;
 997         struct rpc_clnt *ds_clnt;
 998         u32 idx;
 999         struct nfs_fh *fh;
1000
1001         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1002         ds = nfs4_fl_prepare_ds(lseg, idx);
1003         if (!ds)
1004                 goto out_err;
1005
1006         ds_clnt = nfs4_find_or_create_ds_client(ds->ds_clp, data->inode);
1007         if (IS_ERR(ds_clnt))
1008                 goto out_err;
1009
1010         dprintk("%s ino %lu, how %d cl_count %d\n", __func__,
1011                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count));
1012         data->commit_done_cb = filelayout_commit_done_cb;
1013         refcount_inc(&ds->ds_clp->cl_count);
1014         data->ds_clp = ds->ds_clp;
1015         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1016         if (fh)
1017                 data->args.fh = fh;
1018         return nfs_initiate_commit(ds_clnt, data, NFS_PROTO(data->inode),
1019                                    &filelayout_commit_call_ops, how,
1020                                    RPC_TASK_SOFTCONN);
1021 out_err:
1022         pnfs_generic_prepare_to_resend_writes(data);
1023         pnfs_generic_commit_release(data);
1024         return -EAGAIN;
1025 }
1026
1027 static int
1028 filelayout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1029                            int how, struct nfs_commit_info *cinfo)
1030 {
1031         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1032                                             filelayout_initiate_commit);
1033 }
1034
1035 static struct nfs4_deviceid_node *
1036 filelayout_alloc_deviceid_node(struct nfs_server *server,
1037                 struct pnfs_device *pdev, gfp_t gfp_flags)
1038 {
1039         struct nfs4_file_layout_dsaddr *dsaddr;
1040
1041         dsaddr = nfs4_fl_alloc_deviceid_node(server, pdev, gfp_flags);
1042         if (!dsaddr)
1043                 return NULL;
1044         return &dsaddr->id_node;
1045 }
1046
1047 static void
1048 filelayout_free_deviceid_node(struct nfs4_deviceid_node *d)
1049 {
1050         nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node));
1051 }
1052
1053 static struct pnfs_layout_hdr *
1054 filelayout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
1055 {
1056         struct nfs4_filelayout *flo;
1057
1058         flo = kzalloc(sizeof(*flo), gfp_flags);
1059         if (flo == NULL)
1060                 return NULL;
1061         pnfs_init_ds_commit_info(&flo->commit_info);
1062         flo->commit_info.ops = &filelayout_commit_ops;
1063         return &flo->generic_hdr;
1064 }
1065
1066 static void
1067 filelayout_free_layout_hdr(struct pnfs_layout_hdr *lo)
1068 {
1069         kfree_rcu(FILELAYOUT_FROM_HDR(lo), generic_hdr.plh_rcu);
1070 }
1071
1072 static struct pnfs_ds_commit_info *
1073 filelayout_get_ds_info(struct inode *inode)
1074 {
1075         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1076
1077         if (layout == NULL)
1078                 return NULL;
1079         else
1080                 return &FILELAYOUT_FROM_HDR(layout)->commit_info;
1081 }
1082
1083 static void
1084 filelayout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
1085                 struct pnfs_layout_segment *lseg)
1086 {
1087         struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);
1088         struct inode *inode = lseg->pls_layout->plh_inode;
1089         struct pnfs_commit_array *array, *new;
1090         unsigned int size = (fl->stripe_type == STRIPE_SPARSE) ?
1091                 fl->dsaddr->ds_num : fl->dsaddr->stripe_count;
1092
1093         new = pnfs_alloc_commit_array(size, nfs_io_gfp_mask());
1094         if (new) {
1095                 spin_lock(&inode->i_lock);
1096                 array = pnfs_add_commit_array(fl_cinfo, new, lseg);
1097                 spin_unlock(&inode->i_lock);
1098                 if (array != new)
1099                         pnfs_free_commit_array(new);
1100         }
1101 }
1102
1103 static void
1104 filelayout_release_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
1105                 struct inode *inode)
1106 {
1107         spin_lock(&inode->i_lock);
1108         pnfs_generic_ds_cinfo_destroy(fl_cinfo);
1109         spin_unlock(&inode->i_lock);
1110 }
1111
1112 static const struct pnfs_commit_ops filelayout_commit_ops = {
1113         .setup_ds_info          = filelayout_setup_ds_info,
1114         .release_ds_info        = filelayout_release_ds_info,
1115         .mark_request_commit    = filelayout_mark_request_commit,
1116         .clear_request_commit   = pnfs_generic_clear_request_commit,
1117         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
1118         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
1119         .search_commit_reqs     = pnfs_generic_search_commit_reqs,
1120         .commit_pagelist        = filelayout_commit_pagelist,
1121 };
1122
1123 static struct pnfs_layoutdriver_type filelayout_type = {
1124         .id                     = LAYOUT_NFSV4_1_FILES,
1125         .name                   = "LAYOUT_NFSV4_1_FILES",
1126         .owner                  = THIS_MODULE,
1127         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
1128         .max_layoutget_response = 4096, /* 1 page or so... */
1129         .alloc_layout_hdr       = filelayout_alloc_layout_hdr,
1130         .free_layout_hdr        = filelayout_free_layout_hdr,
1131         .alloc_lseg             = filelayout_alloc_lseg,
1132         .free_lseg              = filelayout_free_lseg,
1133         .pg_read_ops            = &filelayout_pg_read_ops,
1134         .pg_write_ops           = &filelayout_pg_write_ops,
1135         .get_ds_info            = &filelayout_get_ds_info,
1136         .read_pagelist          = filelayout_read_pagelist,
1137         .write_pagelist         = filelayout_write_pagelist,
1138         .alloc_deviceid_node    = filelayout_alloc_deviceid_node,
1139         .free_deviceid_node     = filelayout_free_deviceid_node,
1140         .sync                   = pnfs_nfs_generic_sync,
1141 };
1142
1143 static int __init nfs4filelayout_init(void)
1144 {
1145         printk(KERN_INFO "%s: NFSv4 File Layout Driver Registering...\n",
1146                __func__);
1147         return pnfs_register_layoutdriver(&filelayout_type);
1148 }
1149
1150 static void __exit nfs4filelayout_exit(void)
1151 {
1152         printk(KERN_INFO "%s: NFSv4 File Layout Driver Unregistering...\n",
1153                __func__);
1154         pnfs_unregister_layoutdriver(&filelayout_type);
1155 }
1156
1157 MODULE_ALIAS("nfs-layouttype4-1");
1158
1159 module_init(nfs4filelayout_init);
1160 module_exit(nfs4filelayout_exit);