fs/nfs/flexfilelayout/flexfilelayout.c

   1 /*
   2  * Module for pnfs flexfile layout driver.
   3  *
   4  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   5  *
   6  * Tao Peng <bergwolf@primarydata.com>
   7  */
   8
   9 #include <linux/nfs_fs.h>
  10 #include <linux/nfs_page.h>
  11 #include <linux/module.h>
  12
  13 #include <linux/sunrpc/metrics.h>
  14
  15 #include "flexfilelayout.h"
  16 #include "../nfs4session.h"
  17 #include "../nfs4idmap.h"
  18 #include "../internal.h"
  19 #include "../delegation.h"
  20 #include "../nfs4trace.h"
  21 #include "../iostat.h"
  22 #include "../nfs.h"
  23 #include "../nfs42.h"
  24
  25 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  26
  27 #define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  28
  29 static struct pnfs_layout_hdr *
  30 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  31 {
  32         struct nfs4_flexfile_layout *ffl;
  33
  34         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  35         if (ffl) {
  36                 INIT_LIST_HEAD(&ffl->error_list);
  37                 return &ffl->generic_hdr;
  38         } else
  39                 return NULL;
  40 }
  41
  42 static void
  43 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  44 {
  45         struct nfs4_ff_layout_ds_err *err, *n;
  46
  47         list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  48                                  list) {
  49                 list_del(&err->list);
  50                 kfree(err);
  51         }
  52         kfree(FF_LAYOUT_FROM_HDR(lo));
  53 }
  54
  55 static int decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  56 {
  57         __be32 *p;
  58
  59         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  60         if (unlikely(p == NULL))
  61                 return -ENOBUFS;
  62         memcpy(stateid, p, NFS4_STATEID_SIZE);
  63         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  64                 p[0], p[1], p[2], p[3]);
  65         return 0;
  66 }
  67
  68 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  69 {
  70         __be32 *p;
  71
  72         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  73         if (unlikely(!p))
  74                 return -ENOBUFS;
  75         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  76         nfs4_print_deviceid(devid);
  77         return 0;
  78 }
  79
  80 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  81 {
  82         __be32 *p;
  83
  84         p = xdr_inline_decode(xdr, 4);
  85         if (unlikely(!p))
  86                 return -ENOBUFS;
  87         fh->size = be32_to_cpup(p++);
  88         if (fh->size > sizeof(struct nfs_fh)) {
  89                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
  90                        fh->size);
  91                 return -EOVERFLOW;
  92         }
  93         /* fh.data */
  94         p = xdr_inline_decode(xdr, fh->size);
  95         if (unlikely(!p))
  96                 return -ENOBUFS;
  97         memcpy(&fh->data, p, fh->size);
  98         dprintk("%s: fh len %d\n", __func__, fh->size);
  99
 100         return 0;
 101 }
 102
 103 /*
 104  * Currently only stringified uids and gids are accepted.
 105  * I.e., kerberos is not supported to the DSes, so no pricipals.
 106  *
 107  * That means that one common function will suffice, but when
 108  * principals are added, this should be split to accomodate
 109  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 110  */
 111 static int
 112 decode_name(struct xdr_stream *xdr, u32 *id)
 113 {
 114         __be32 *p;
 115         int len;
 116
 117         /* opaque_length(4)*/
 118         p = xdr_inline_decode(xdr, 4);
 119         if (unlikely(!p))
 120                 return -ENOBUFS;
 121         len = be32_to_cpup(p++);
 122         if (len < 0)
 123                 return -EINVAL;
 124
 125         dprintk("%s: len %u\n", __func__, len);
 126
 127         /* opaque body */
 128         p = xdr_inline_decode(xdr, len);
 129         if (unlikely(!p))
 130                 return -ENOBUFS;
 131
 132         if (!nfs_map_string_to_numeric((char *)p, len, id))
 133                 return -EINVAL;
 134
 135         return 0;
 136 }
 137
 138 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 139 {
 140         int i;
 141
 142         if (fls->mirror_array) {
 143                 for (i = 0; i < fls->mirror_array_cnt; i++) {
 144                         /* normally mirror_ds is freed in
 145                          * .free_deviceid_node but we still do it here
 146                          * for .alloc_lseg error path */
 147                         if (fls->mirror_array[i]) {
 148                                 kfree(fls->mirror_array[i]->fh_versions);
 149                                 nfs4_ff_layout_put_deviceid(fls->mirror_array[i]->mirror_ds);
 150                                 kfree(fls->mirror_array[i]);
 151                         }
 152                 }
 153                 kfree(fls->mirror_array);
 154                 fls->mirror_array = NULL;
 155         }
 156 }
 157
 158 static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 159 {
 160         int ret = 0;
 161
 162         dprintk("--> %s\n", __func__);
 163
 164         /* FIXME: remove this check when layout segment support is added */
 165         if (lgr->range.offset != 0 ||
 166             lgr->range.length != NFS4_MAX_UINT64) {
 167                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 168                         __func__);
 169                 ret = -EINVAL;
 170         }
 171
 172         dprintk("--> %s returns %d\n", __func__, ret);
 173         return ret;
 174 }
 175
 176 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 177 {
 178         if (fls) {
 179                 ff_layout_free_mirror_array(fls);
 180                 kfree(fls);
 181         }
 182 }
 183
 184 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 185 {
 186         int i, j;
 187
 188         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 189                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 190                         if (fls->mirror_array[i]->efficiency <
 191                             fls->mirror_array[j]->efficiency)
 192                                 swap(fls->mirror_array[i],
 193                                      fls->mirror_array[j]);
 194         }
 195 }
 196
 197 static struct pnfs_layout_segment *
 198 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 199                      struct nfs4_layoutget_res *lgr,
 200                      gfp_t gfp_flags)
 201 {
 202         struct pnfs_layout_segment *ret;
 203         struct nfs4_ff_layout_segment *fls = NULL;
 204         struct xdr_stream stream;
 205         struct xdr_buf buf;
 206         struct page *scratch;
 207         u64 stripe_unit;
 208         u32 mirror_array_cnt;
 209         __be32 *p;
 210         int i, rc;
 211
 212         dprintk("--> %s\n", __func__);
 213         scratch = alloc_page(gfp_flags);
 214         if (!scratch)
 215                 return ERR_PTR(-ENOMEM);
 216
 217         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 218                               lgr->layoutp->len);
 219         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 220
 221         /* stripe unit and mirror_array_cnt */
 222         rc = -EIO;
 223         p = xdr_inline_decode(&stream, 8 + 4);
 224         if (!p)
 225                 goto out_err_free;
 226
 227         p = xdr_decode_hyper(p, &stripe_unit);
 228         mirror_array_cnt = be32_to_cpup(p++);
 229         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 230                 stripe_unit, mirror_array_cnt);
 231
 232         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 233             mirror_array_cnt == 0)
 234                 goto out_err_free;
 235
 236         rc = -ENOMEM;
 237         fls = kzalloc(sizeof(*fls), gfp_flags);
 238         if (!fls)
 239                 goto out_err_free;
 240
 241         fls->mirror_array_cnt = mirror_array_cnt;
 242         fls->stripe_unit = stripe_unit;
 243         fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 244                                     sizeof(fls->mirror_array[0]), gfp_flags);
 245         if (fls->mirror_array == NULL)
 246                 goto out_err_free;
 247
 248         for (i = 0; i < fls->mirror_array_cnt; i++) {
 249                 struct nfs4_deviceid devid;
 250                 struct nfs4_deviceid_node *idnode;
 251                 u32 ds_count;
 252                 u32 fh_count;
 253                 int j;
 254
 255                 rc = -EIO;
 256                 p = xdr_inline_decode(&stream, 4);
 257                 if (!p)
 258                         goto out_err_free;
 259                 ds_count = be32_to_cpup(p);
 260
 261                 /* FIXME: allow for striping? */
 262                 if (ds_count != 1)
 263                         goto out_err_free;
 264
 265                 fls->mirror_array[i] =
 266                         kzalloc(sizeof(struct nfs4_ff_layout_mirror),
 267                                 gfp_flags);
 268                 if (fls->mirror_array[i] == NULL) {
 269                         rc = -ENOMEM;
 270                         goto out_err_free;
 271                 }
 272
 273                 spin_lock_init(&fls->mirror_array[i]->lock);
 274                 fls->mirror_array[i]->ds_count = ds_count;
 275                 fls->mirror_array[i]->lseg = &fls->generic_hdr;
 276
 277                 /* deviceid */
 278                 rc = decode_deviceid(&stream, &devid);
 279                 if (rc)
 280                         goto out_err_free;
 281
 282                 idnode = nfs4_find_get_deviceid(NFS_SERVER(lh->plh_inode),
 283                                                 &devid, lh->plh_lc_cred,
 284                                                 gfp_flags);
 285                 /*
 286                  * upon success, mirror_ds is allocated by previous
 287                  * getdeviceinfo, or newly by .alloc_deviceid_node
 288                  * nfs4_find_get_deviceid failure is indeed getdeviceinfo falure
 289                  */
 290                 if (idnode)
 291                         fls->mirror_array[i]->mirror_ds =
 292                                 FF_LAYOUT_MIRROR_DS(idnode);
 293                 else
 294                         goto out_err_free;
 295
 296                 /* efficiency */
 297                 rc = -EIO;
 298                 p = xdr_inline_decode(&stream, 4);
 299                 if (!p)
 300                         goto out_err_free;
 301                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 302
 303                 /* stateid */
 304                 rc = decode_stateid(&stream, &fls->mirror_array[i]->stateid);
 305                 if (rc)
 306                         goto out_err_free;
 307
 308                 /* fh */
 309                 p = xdr_inline_decode(&stream, 4);
 310                 if (!p)
 311                         goto out_err_free;
 312                 fh_count = be32_to_cpup(p);
 313
 314                 fls->mirror_array[i]->fh_versions =
 315                         kzalloc(fh_count * sizeof(struct nfs_fh),
 316                                 gfp_flags);
 317                 if (fls->mirror_array[i]->fh_versions == NULL) {
 318                         rc = -ENOMEM;
 319                         goto out_err_free;
 320                 }
 321
 322                 for (j = 0; j < fh_count; j++) {
 323                         rc = decode_nfs_fh(&stream,
 324                                            &fls->mirror_array[i]->fh_versions[j]);
 325                         if (rc)
 326                                 goto out_err_free;
 327                 }
 328
 329                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 330
 331                 /* user */
 332                 rc = decode_name(&stream, &fls->mirror_array[i]->uid);
 333                 if (rc)
 334                         goto out_err_free;
 335
 336                 /* group */
 337                 rc = decode_name(&stream, &fls->mirror_array[i]->gid);
 338                 if (rc)
 339                         goto out_err_free;
 340
 341                 dprintk("%s: uid %d gid %d\n", __func__,
 342                         fls->mirror_array[i]->uid,
 343                         fls->mirror_array[i]->gid);
 344         }
 345
 346         ff_layout_sort_mirrors(fls);
 347         rc = ff_layout_check_layout(lgr);
 348         if (rc)
 349                 goto out_err_free;
 350
 351         ret = &fls->generic_hdr;
 352         dprintk("<-- %s (success)\n", __func__);
 353 out_free_page:
 354         __free_page(scratch);
 355         return ret;
 356 out_err_free:
 357         _ff_layout_free_lseg(fls);
 358         ret = ERR_PTR(rc);
 359         dprintk("<-- %s (%d)\n", __func__, rc);
 360         goto out_free_page;
 361 }
 362
 363 static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 364 {
 365         struct pnfs_layout_segment *lseg;
 366
 367         list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 368                 if (lseg->pls_range.iomode == IOMODE_RW)
 369                         return true;
 370
 371         return false;
 372 }
 373
 374 static void
 375 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 376 {
 377         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 378         int i;
 379
 380         dprintk("--> %s\n", __func__);
 381
 382         for (i = 0; i < fls->mirror_array_cnt; i++) {
 383                 if (fls->mirror_array[i]) {
 384                         nfs4_ff_layout_put_deviceid(fls->mirror_array[i]->mirror_ds);
 385                         fls->mirror_array[i]->mirror_ds = NULL;
 386                         if (fls->mirror_array[i]->cred) {
 387                                 put_rpccred(fls->mirror_array[i]->cred);
 388                                 fls->mirror_array[i]->cred = NULL;
 389                         }
 390                 }
 391         }
 392
 393         if (lseg->pls_range.iomode == IOMODE_RW) {
 394                 struct nfs4_flexfile_layout *ffl;
 395                 struct inode *inode;
 396
 397                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 398                 inode = ffl->generic_hdr.plh_inode;
 399                 spin_lock(&inode->i_lock);
 400                 if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 401                         ffl->commit_info.nbuckets = 0;
 402                         kfree(ffl->commit_info.buckets);
 403                         ffl->commit_info.buckets = NULL;
 404                 }
 405                 spin_unlock(&inode->i_lock);
 406         }
 407         _ff_layout_free_lseg(fls);
 408 }
 409
 410 /* Return 1 until we have multiple lsegs support */
 411 static int
 412 ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 413 {
 414         return 1;
 415 }
 416
 417 static void
 418 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer)
 419 {
 420         ktime_t old, new;
 421
 422         /*
 423          * Note: careful here!
 424          * If the counter is zero, then we must not increment it until after
 425          * we've set the start_time.
 426          * If we were instead to use atomic_inc_return(), then another
 427          * request might come in, bump, and then call end_busy_timer()
 428          * before we've set the timer->start_time.
 429          */
 430         old = timer->start_time;
 431         if (atomic_inc_not_zero(&timer->n_ops) == 0) {
 432                 new = ktime_get();
 433                 cmpxchg(&timer->start_time.tv64, old.tv64, new.tv64);
 434                 atomic_inc(&timer->n_ops);
 435         }
 436 }
 437
 438 static ktime_t
 439 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer)
 440 {
 441         ktime_t start, now;
 442
 443         now = ktime_get();
 444         start.tv64 = xchg(&timer->start_time.tv64, now.tv64);
 445         atomic_dec(&timer->n_ops);
 446         return ktime_sub(now, start);
 447 }
 448
 449 static ktime_t
 450 nfs4_ff_layout_calc_completion_time(struct rpc_task *task)
 451 {
 452         return ktime_sub(ktime_get(), task->tk_start);
 453 }
 454
 455 static void
 456 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 457                             struct nfs4_ff_layoutstat *layoutstat)
 458 {
 459         static const ktime_t notime = {0};
 460
 461         nfs4_ff_start_busy_timer(&layoutstat->busy_timer);
 462         cmpxchg(&mirror->start_time, notime, ktime_get());
 463 }
 464
 465 static void
 466 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 467                 __u64 requested)
 468 {
 469         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 470
 471         iostat->ops_requested++;
 472         iostat->bytes_requested += requested;
 473 }
 474
 475 static void
 476 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 477                 __u64 requested,
 478                 __u64 completed,
 479                 ktime_t time_completed)
 480 {
 481         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 482         ktime_t timer;
 483
 484         iostat->ops_completed++;
 485         iostat->bytes_completed += completed;
 486         iostat->bytes_not_delivered += requested - completed;
 487
 488         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer);
 489         iostat->total_busy_time =
 490                         ktime_add(iostat->total_busy_time, timer);
 491         iostat->aggregate_completion_time =
 492                         ktime_add(iostat->aggregate_completion_time, time_completed);
 493 }
 494
 495 static void
 496 nfs4_ff_layout_stat_io_start_read(struct nfs4_ff_layout_mirror *mirror,
 497                 __u64 requested)
 498 {
 499         spin_lock(&mirror->lock);
 500         nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat);
 501         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 502         spin_unlock(&mirror->lock);
 503 }
 504
 505 static void
 506 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 507                 struct nfs4_ff_layout_mirror *mirror,
 508                 __u64 requested,
 509                 __u64 completed)
 510 {
 511         spin_lock(&mirror->lock);
 512         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 513                         requested, completed,
 514                         nfs4_ff_layout_calc_completion_time(task));
 515         spin_unlock(&mirror->lock);
 516 }
 517
 518 static void
 519 nfs4_ff_layout_stat_io_start_write(struct nfs4_ff_layout_mirror *mirror,
 520                 __u64 requested)
 521 {
 522         spin_lock(&mirror->lock);
 523         nfs4_ff_layoutstat_start_io(mirror, &mirror->write_stat);
 524         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 525         spin_unlock(&mirror->lock);
 526 }
 527
 528 static void
 529 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 530                 struct nfs4_ff_layout_mirror *mirror,
 531                 __u64 requested,
 532                 __u64 completed,
 533                 enum nfs3_stable_how committed)
 534 {
 535         if (committed == NFS_UNSTABLE)
 536                 requested = completed = 0;
 537
 538         spin_lock(&mirror->lock);
 539         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 540                         requested, completed,
 541                         nfs4_ff_layout_calc_completion_time(task));
 542         spin_unlock(&mirror->lock);
 543 }
 544
 545 static int
 546 ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 547                             struct nfs_commit_info *cinfo,
 548                             gfp_t gfp_flags)
 549 {
 550         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 551         struct pnfs_commit_bucket *buckets;
 552         int size;
 553
 554         if (cinfo->ds->nbuckets != 0) {
 555                 /* This assumes there is only one RW lseg per file.
 556                  * To support multiple lseg per file, we need to
 557                  * change struct pnfs_commit_bucket to allow dynamic
 558                  * increasing nbuckets.
 559                  */
 560                 return 0;
 561         }
 562
 563         size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 564
 565         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 566                           gfp_flags);
 567         if (!buckets)
 568                 return -ENOMEM;
 569         else {
 570                 int i;
 571
 572                 spin_lock(cinfo->lock);
 573                 if (cinfo->ds->nbuckets != 0)
 574                         kfree(buckets);
 575                 else {
 576                         cinfo->ds->buckets = buckets;
 577                         cinfo->ds->nbuckets = size;
 578                         for (i = 0; i < size; i++) {
 579                                 INIT_LIST_HEAD(&buckets[i].written);
 580                                 INIT_LIST_HEAD(&buckets[i].committing);
 581                                 /* mark direct verifier as unset */
 582                                 buckets[i].direct_verf.committed =
 583                                         NFS_INVALID_STABLE_HOW;
 584                         }
 585                 }
 586                 spin_unlock(cinfo->lock);
 587                 return 0;
 588         }
 589 }
 590
 591 static struct nfs4_pnfs_ds *
 592 ff_layout_choose_best_ds_for_read(struct nfs_pageio_descriptor *pgio,
 593                                   int *best_idx)
 594 {
 595         struct nfs4_ff_layout_segment *fls;
 596         struct nfs4_pnfs_ds *ds;
 597         int idx;
 598
 599         fls = FF_LAYOUT_LSEG(pgio->pg_lseg);
 600         /* mirrors are sorted by efficiency */
 601         for (idx = 0; idx < fls->mirror_array_cnt; idx++) {
 602                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, idx, false);
 603                 if (ds) {
 604                         *best_idx = idx;
 605                         return ds;
 606                 }
 607         }
 608
 609         return NULL;
 610 }
 611
 612 static void
 613 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 614                         struct nfs_page *req)
 615 {
 616         struct nfs_pgio_mirror *pgm;
 617         struct nfs4_ff_layout_mirror *mirror;
 618         struct nfs4_pnfs_ds *ds;
 619         int ds_idx;
 620
 621         /* Use full layout for now */
 622         if (!pgio->pg_lseg)
 623                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 624                                                    req->wb_context,
 625                                                    0,
 626                                                    NFS4_MAX_UINT64,
 627                                                    IOMODE_READ,
 628                                                    GFP_KERNEL);
 629         /* If no lseg, fall back to read through mds */
 630         if (pgio->pg_lseg == NULL)
 631                 goto out_mds;
 632
 633         ds = ff_layout_choose_best_ds_for_read(pgio, &ds_idx);
 634         if (!ds)
 635                 goto out_mds;
 636         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 637
 638         pgio->pg_mirror_idx = ds_idx;
 639
 640         /* read always uses only one mirror - idx 0 for pgio layer */
 641         pgm = &pgio->pg_mirrors[0];
 642         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 643
 644         return;
 645 out_mds:
 646         pnfs_put_lseg(pgio->pg_lseg);
 647         pgio->pg_lseg = NULL;
 648         nfs_pageio_reset_read_mds(pgio);
 649 }
 650
 651 static void
 652 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 653                         struct nfs_page *req)
 654 {
 655         struct nfs4_ff_layout_mirror *mirror;
 656         struct nfs_pgio_mirror *pgm;
 657         struct nfs_commit_info cinfo;
 658         struct nfs4_pnfs_ds *ds;
 659         int i;
 660         int status;
 661
 662         if (!pgio->pg_lseg)
 663                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 664                                                    req->wb_context,
 665                                                    0,
 666                                                    NFS4_MAX_UINT64,
 667                                                    IOMODE_RW,
 668                                                    GFP_NOFS);
 669         /* If no lseg, fall back to write through mds */
 670         if (pgio->pg_lseg == NULL)
 671                 goto out_mds;
 672
 673         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 674         status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 675         if (status < 0)
 676                 goto out_mds;
 677
 678         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 679         if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 680             FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 681                 goto out_mds;
 682
 683         for (i = 0; i < pgio->pg_mirror_count; i++) {
 684                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
 685                 if (!ds)
 686                         goto out_mds;
 687                 pgm = &pgio->pg_mirrors[i];
 688                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 689                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 690         }
 691
 692         return;
 693
 694 out_mds:
 695         pnfs_put_lseg(pgio->pg_lseg);
 696         pgio->pg_lseg = NULL;
 697         nfs_pageio_reset_write_mds(pgio);
 698 }
 699
 700 static unsigned int
 701 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 702                                     struct nfs_page *req)
 703 {
 704         if (!pgio->pg_lseg)
 705                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 706                                                    req->wb_context,
 707                                                    0,
 708                                                    NFS4_MAX_UINT64,
 709                                                    IOMODE_RW,
 710                                                    GFP_NOFS);
 711         if (pgio->pg_lseg)
 712                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 713
 714         /* no lseg means that pnfs is not in use, so no mirroring here */
 715         pnfs_put_lseg(pgio->pg_lseg);
 716         pgio->pg_lseg = NULL;
 717         nfs_pageio_reset_write_mds(pgio);
 718         return 1;
 719 }
 720
 721 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 722         .pg_init = ff_layout_pg_init_read,
 723         .pg_test = pnfs_generic_pg_test,
 724         .pg_doio = pnfs_generic_pg_readpages,
 725         .pg_cleanup = pnfs_generic_pg_cleanup,
 726 };
 727
 728 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 729         .pg_init = ff_layout_pg_init_write,
 730         .pg_test = pnfs_generic_pg_test,
 731         .pg_doio = pnfs_generic_pg_writepages,
 732         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
 733         .pg_cleanup = pnfs_generic_pg_cleanup,
 734 };
 735
 736 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
 737 {
 738         struct rpc_task *task = &hdr->task;
 739
 740         pnfs_layoutcommit_inode(hdr->inode, false);
 741
 742         if (retry_pnfs) {
 743                 dprintk("%s Reset task %5u for i/o through pNFS "
 744                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 745                         hdr->task.tk_pid,
 746                         hdr->inode->i_sb->s_id,
 747                         (unsigned long long)NFS_FILEID(hdr->inode),
 748                         hdr->args.count,
 749                         (unsigned long long)hdr->args.offset);
 750
 751                 if (!hdr->dreq) {
 752                         struct nfs_open_context *ctx;
 753
 754                         ctx = nfs_list_entry(hdr->pages.next)->wb_context;
 755                         set_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags);
 756                         hdr->completion_ops->error_cleanup(&hdr->pages);
 757                 } else {
 758                         nfs_direct_set_resched_writes(hdr->dreq);
 759                         /* fake unstable write to let common nfs resend pages */
 760                         hdr->verf.committed = NFS_UNSTABLE;
 761                         hdr->good_bytes = 0;
 762                 }
 763                 return;
 764         }
 765
 766         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 767                 dprintk("%s Reset task %5u for i/o through MDS "
 768                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 769                         hdr->task.tk_pid,
 770                         hdr->inode->i_sb->s_id,
 771                         (unsigned long long)NFS_FILEID(hdr->inode),
 772                         hdr->args.count,
 773                         (unsigned long long)hdr->args.offset);
 774
 775                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
 776         }
 777 }
 778
 779 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
 780 {
 781         struct rpc_task *task = &hdr->task;
 782
 783         pnfs_layoutcommit_inode(hdr->inode, false);
 784
 785         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
 786                 dprintk("%s Reset task %5u for i/o through MDS "
 787                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
 788                         hdr->task.tk_pid,
 789                         hdr->inode->i_sb->s_id,
 790                         (unsigned long long)NFS_FILEID(hdr->inode),
 791                         hdr->args.count,
 792                         (unsigned long long)hdr->args.offset);
 793
 794                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
 795         }
 796 }
 797
 798 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 799                                            struct nfs4_state *state,
 800                                            struct nfs_client *clp,
 801                                            struct pnfs_layout_segment *lseg,
 802                                            int idx)
 803 {
 804         struct pnfs_layout_hdr *lo = lseg->pls_layout;
 805         struct inode *inode = lo->plh_inode;
 806         struct nfs_server *mds_server = NFS_SERVER(inode);
 807
 808         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 809         struct nfs_client *mds_client = mds_server->nfs_client;
 810         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
 811
 812         if (task->tk_status >= 0)
 813                 return 0;
 814
 815         switch (task->tk_status) {
 816         /* MDS state errors */
 817         case -NFS4ERR_DELEG_REVOKED:
 818         case -NFS4ERR_ADMIN_REVOKED:
 819         case -NFS4ERR_BAD_STATEID:
 820                 if (state == NULL)
 821                         break;
 822                 nfs_remove_bad_delegation(state->inode);
 823         case -NFS4ERR_OPENMODE:
 824                 if (state == NULL)
 825                         break;
 826                 if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 827                         goto out_bad_stateid;
 828                 goto wait_on_recovery;
 829         case -NFS4ERR_EXPIRED:
 830                 if (state != NULL) {
 831                         if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
 832                                 goto out_bad_stateid;
 833                 }
 834                 nfs4_schedule_lease_recovery(mds_client);
 835                 goto wait_on_recovery;
 836         /* DS session errors */
 837         case -NFS4ERR_BADSESSION:
 838         case -NFS4ERR_BADSLOT:
 839         case -NFS4ERR_BAD_HIGH_SLOT:
 840         case -NFS4ERR_DEADSESSION:
 841         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 842         case -NFS4ERR_SEQ_FALSE_RETRY:
 843         case -NFS4ERR_SEQ_MISORDERED:
 844                 dprintk("%s ERROR %d, Reset session. Exchangeid "
 845                         "flags 0x%x\n", __func__, task->tk_status,
 846                         clp->cl_exchange_flags);
 847                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
 848                 break;
 849         case -NFS4ERR_DELAY:
 850         case -NFS4ERR_GRACE:
 851                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
 852                 break;
 853         case -NFS4ERR_RETRY_UNCACHED_REP:
 854                 break;
 855         /* Invalidate Layout errors */
 856         case -NFS4ERR_PNFS_NO_LAYOUT:
 857         case -ESTALE:           /* mapped NFS4ERR_STALE */
 858         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
 859         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
 860         case -NFS4ERR_FHEXPIRED:
 861         case -NFS4ERR_WRONG_TYPE:
 862                 dprintk("%s Invalid layout error %d\n", __func__,
 863                         task->tk_status);
 864                 /*
 865                  * Destroy layout so new i/o will get a new layout.
 866                  * Layout will not be destroyed until all current lseg
 867                  * references are put. Mark layout as invalid to resend failed
 868                  * i/o and all i/o waiting on the slot table to the MDS until
 869                  * layout is destroyed and a new valid layout is obtained.
 870                  */
 871                 pnfs_destroy_layout(NFS_I(inode));
 872                 rpc_wake_up(&tbl->slot_tbl_waitq);
 873                 goto reset;
 874         /* RPC connection errors */
 875         case -ECONNREFUSED:
 876         case -EHOSTDOWN:
 877         case -EHOSTUNREACH:
 878         case -ENETUNREACH:
 879         case -EIO:
 880         case -ETIMEDOUT:
 881         case -EPIPE:
 882                 dprintk("%s DS connection error %d\n", __func__,
 883                         task->tk_status);
 884                 nfs4_mark_deviceid_unavailable(devid);
 885                 rpc_wake_up(&tbl->slot_tbl_waitq);
 886                 /* fall through */
 887         default:
 888                 if (ff_layout_has_available_ds(lseg))
 889                         return -NFS4ERR_RESET_TO_PNFS;
 890 reset:
 891                 dprintk("%s Retry through MDS. Error %d\n", __func__,
 892                         task->tk_status);
 893                 return -NFS4ERR_RESET_TO_MDS;
 894         }
 895 out:
 896         task->tk_status = 0;
 897         return -EAGAIN;
 898 out_bad_stateid:
 899         task->tk_status = -EIO;
 900         return 0;
 901 wait_on_recovery:
 902         rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
 903         if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
 904                 rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
 905         goto out;
 906 }
 907
 908 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
 909 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
 910                                            struct pnfs_layout_segment *lseg,
 911                                            int idx)
 912 {
 913         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 914
 915         if (task->tk_status >= 0)
 916                 return 0;
 917
 918         if (task->tk_status != -EJUKEBOX) {
 919                 dprintk("%s DS connection error %d\n", __func__,
 920                         task->tk_status);
 921                 nfs4_mark_deviceid_unavailable(devid);
 922                 if (ff_layout_has_available_ds(lseg))
 923                         return -NFS4ERR_RESET_TO_PNFS;
 924                 else
 925                         return -NFS4ERR_RESET_TO_MDS;
 926         }
 927
 928         if (task->tk_status == -EJUKEBOX)
 929                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
 930         task->tk_status = 0;
 931         rpc_restart_call(task);
 932         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
 933         return -EAGAIN;
 934 }
 935
 936 static int ff_layout_async_handle_error(struct rpc_task *task,
 937                                         struct nfs4_state *state,
 938                                         struct nfs_client *clp,
 939                                         struct pnfs_layout_segment *lseg,
 940                                         int idx)
 941 {
 942         int vers = clp->cl_nfs_mod->rpc_vers->number;
 943
 944         switch (vers) {
 945         case 3:
 946                 return ff_layout_async_handle_error_v3(task, lseg, idx);
 947         case 4:
 948                 return ff_layout_async_handle_error_v4(task, state, clp,
 949                                                        lseg, idx);
 950         default:
 951                 /* should never happen */
 952                 WARN_ON_ONCE(1);
 953                 return 0;
 954         }
 955 }
 956
 957 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 958                                         int idx, u64 offset, u64 length,
 959                                         u32 status, int opnum)
 960 {
 961         struct nfs4_ff_layout_mirror *mirror;
 962         int err;
 963
 964         mirror = FF_LAYOUT_COMP(lseg, idx);
 965         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
 966                                        mirror, offset, length, status, opnum,
 967                                        GFP_NOIO);
 968         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
 969 }
 970
 971 /* NFS_PROTO call done callback routines */
 972
 973 static int ff_layout_read_done_cb(struct rpc_task *task,
 974                                 struct nfs_pgio_header *hdr)
 975 {
 976         struct inode *inode;
 977         int err;
 978
 979         trace_nfs4_pnfs_read(hdr, task->tk_status);
 980         if (task->tk_status == -ETIMEDOUT && !hdr->res.op_status)
 981                 hdr->res.op_status = NFS4ERR_NXIO;
 982         if (task->tk_status < 0 && hdr->res.op_status)
 983                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
 984                                             hdr->args.offset, hdr->args.count,
 985                                             hdr->res.op_status, OP_READ);
 986         err = ff_layout_async_handle_error(task, hdr->args.context->state,
 987                                            hdr->ds_clp, hdr->lseg,
 988                                            hdr->pgio_mirror_idx);
 989
 990         switch (err) {
 991         case -NFS4ERR_RESET_TO_PNFS:
 992                 set_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
 993                         &hdr->lseg->pls_layout->plh_flags);
 994                 pnfs_read_resend_pnfs(hdr);
 995                 return task->tk_status;
 996         case -NFS4ERR_RESET_TO_MDS:
 997                 inode = hdr->lseg->pls_layout->plh_inode;
 998                 pnfs_error_mark_layout_for_return(inode, hdr->lseg);
 999                 ff_layout_reset_read(hdr);
1000                 return task->tk_status;
1001         case -EAGAIN:
1002                 rpc_restart_call_prepare(task);
1003                 return -EAGAIN;
1004         }
1005
1006         return 0;
1007 }
1008
1009 /*
1010  * We reference the rpc_cred of the first WRITE that triggers the need for
1011  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1012  * rfc5661 is not clear about which credential should be used.
1013  *
1014  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1015  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1016  * we always send layoutcommit after DS writes.
1017  */
1018 static void
1019 ff_layout_set_layoutcommit(struct nfs_pgio_header *hdr)
1020 {
1021         pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
1022                         hdr->mds_offset + hdr->res.count);
1023         dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
1024                 (unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
1025 }
1026
1027 static bool
1028 ff_layout_reset_to_mds(struct pnfs_layout_segment *lseg, int idx)
1029 {
1030         /* No mirroring for now */
1031         struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
1032
1033         return ff_layout_test_devid_unavailable(node);
1034 }
1035
1036 static int ff_layout_read_prepare_common(struct rpc_task *task,
1037                                          struct nfs_pgio_header *hdr)
1038 {
1039         nfs4_ff_layout_stat_io_start_read(
1040                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1041                         hdr->args.count);
1042
1043         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1044                 rpc_exit(task, -EIO);
1045                 return -EIO;
1046         }
1047         if (ff_layout_reset_to_mds(hdr->lseg, hdr->pgio_mirror_idx)) {
1048                 dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
1049                 if (ff_layout_has_available_ds(hdr->lseg))
1050                         pnfs_read_resend_pnfs(hdr);
1051                 else
1052                         ff_layout_reset_read(hdr);
1053                 rpc_exit(task, 0);
1054                 return -EAGAIN;
1055         }
1056         hdr->pgio_done_cb = ff_layout_read_done_cb;
1057
1058         return 0;
1059 }
1060
1061 /*
1062  * Call ops for the async read/write cases
1063  * In the case of dense layouts, the offset needs to be reset to its
1064  * original value.
1065  */
1066 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1067 {
1068         struct nfs_pgio_header *hdr = data;
1069
1070         if (ff_layout_read_prepare_common(task, hdr))
1071                 return;
1072
1073         rpc_call_start(task);
1074 }
1075
1076 static int ff_layout_setup_sequence(struct nfs_client *ds_clp,
1077                                     struct nfs4_sequence_args *args,
1078                                     struct nfs4_sequence_res *res,
1079                                     struct rpc_task *task)
1080 {
1081         if (ds_clp->cl_session)
1082                 return nfs41_setup_sequence(ds_clp->cl_session,
1083                                            args,
1084                                            res,
1085                                            task);
1086         return nfs40_setup_sequence(ds_clp->cl_slot_tbl,
1087                                    args,
1088                                    res,
1089                                    task);
1090 }
1091
1092 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1093 {
1094         struct nfs_pgio_header *hdr = data;
1095
1096         if (ff_layout_setup_sequence(hdr->ds_clp,
1097                                      &hdr->args.seq_args,
1098                                      &hdr->res.seq_res,
1099                                      task))
1100                 return;
1101
1102         if (ff_layout_read_prepare_common(task, hdr))
1103                 return;
1104
1105         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1106                         hdr->args.lock_context, FMODE_READ) == -EIO)
1107                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1108 }
1109
1110 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1111 {
1112         struct nfs_pgio_header *hdr = data;
1113
1114         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1115
1116         nfs4_ff_layout_stat_io_end_read(task,
1117                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1118                         hdr->args.count, hdr->res.count);
1119
1120         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1121             task->tk_status == 0) {
1122                 nfs4_sequence_done(task, &hdr->res.seq_res);
1123                 return;
1124         }
1125
1126         /* Note this may cause RPC to be resent */
1127         hdr->mds_ops->rpc_call_done(task, hdr);
1128 }
1129
1130 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1131 {
1132         struct nfs_pgio_header *hdr = data;
1133
1134         rpc_count_iostats_metrics(task,
1135             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1136 }
1137
1138 static int ff_layout_write_done_cb(struct rpc_task *task,
1139                                 struct nfs_pgio_header *hdr)
1140 {
1141         struct inode *inode;
1142         int err;
1143
1144         trace_nfs4_pnfs_write(hdr, task->tk_status);
1145         if (task->tk_status == -ETIMEDOUT && !hdr->res.op_status)
1146                 hdr->res.op_status = NFS4ERR_NXIO;
1147         if (task->tk_status < 0 && hdr->res.op_status)
1148                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1149                                             hdr->args.offset, hdr->args.count,
1150                                             hdr->res.op_status, OP_WRITE);
1151         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1152                                            hdr->ds_clp, hdr->lseg,
1153                                            hdr->pgio_mirror_idx);
1154
1155         switch (err) {
1156         case -NFS4ERR_RESET_TO_PNFS:
1157         case -NFS4ERR_RESET_TO_MDS:
1158                 inode = hdr->lseg->pls_layout->plh_inode;
1159                 pnfs_error_mark_layout_for_return(inode, hdr->lseg);
1160                 if (err == -NFS4ERR_RESET_TO_PNFS) {
1161                         pnfs_set_retry_layoutget(hdr->lseg->pls_layout);
1162                         ff_layout_reset_write(hdr, true);
1163                 } else {
1164                         pnfs_clear_retry_layoutget(hdr->lseg->pls_layout);
1165                         ff_layout_reset_write(hdr, false);
1166                 }
1167                 return task->tk_status;
1168         case -EAGAIN:
1169                 rpc_restart_call_prepare(task);
1170                 return -EAGAIN;
1171         }
1172
1173         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1174             hdr->res.verf->committed == NFS_DATA_SYNC)
1175                 ff_layout_set_layoutcommit(hdr);
1176
1177         return 0;
1178 }
1179
1180 static int ff_layout_commit_done_cb(struct rpc_task *task,
1181                                      struct nfs_commit_data *data)
1182 {
1183         struct inode *inode;
1184         int err;
1185
1186         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1187         if (task->tk_status == -ETIMEDOUT && !data->res.op_status)
1188                 data->res.op_status = NFS4ERR_NXIO;
1189         if (task->tk_status < 0 && data->res.op_status)
1190                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1191                                             data->args.offset, data->args.count,
1192                                             data->res.op_status, OP_COMMIT);
1193         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1194                                            data->lseg, data->ds_commit_index);
1195
1196         switch (err) {
1197         case -NFS4ERR_RESET_TO_PNFS:
1198         case -NFS4ERR_RESET_TO_MDS:
1199                 inode = data->lseg->pls_layout->plh_inode;
1200                 pnfs_error_mark_layout_for_return(inode, data->lseg);
1201                 if (err == -NFS4ERR_RESET_TO_PNFS)
1202                         pnfs_set_retry_layoutget(data->lseg->pls_layout);
1203                 else
1204                         pnfs_clear_retry_layoutget(data->lseg->pls_layout);
1205                 pnfs_generic_prepare_to_resend_writes(data);
1206                 return -EAGAIN;
1207         case -EAGAIN:
1208                 rpc_restart_call_prepare(task);
1209                 return -EAGAIN;
1210         }
1211
1212         if (data->verf.committed == NFS_UNSTABLE)
1213                 pnfs_set_layoutcommit(data->inode, data->lseg, data->lwb);
1214
1215         return 0;
1216 }
1217
1218 static int ff_layout_write_prepare_common(struct rpc_task *task,
1219                                           struct nfs_pgio_header *hdr)
1220 {
1221         nfs4_ff_layout_stat_io_start_write(
1222                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1223                         hdr->args.count);
1224
1225         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1226                 rpc_exit(task, -EIO);
1227                 return -EIO;
1228         }
1229
1230         if (ff_layout_reset_to_mds(hdr->lseg, hdr->pgio_mirror_idx)) {
1231                 bool retry_pnfs;
1232
1233                 retry_pnfs = ff_layout_has_available_ds(hdr->lseg);
1234                 dprintk("%s task %u reset io to %s\n", __func__,
1235                         task->tk_pid, retry_pnfs ? "pNFS" : "MDS");
1236                 ff_layout_reset_write(hdr, retry_pnfs);
1237                 rpc_exit(task, 0);
1238                 return -EAGAIN;
1239         }
1240
1241         return 0;
1242 }
1243
1244 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1245 {
1246         struct nfs_pgio_header *hdr = data;
1247
1248         if (ff_layout_write_prepare_common(task, hdr))
1249                 return;
1250
1251         rpc_call_start(task);
1252 }
1253
1254 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1255 {
1256         struct nfs_pgio_header *hdr = data;
1257
1258         if (ff_layout_setup_sequence(hdr->ds_clp,
1259                                      &hdr->args.seq_args,
1260                                      &hdr->res.seq_res,
1261                                      task))
1262                 return;
1263
1264         if (ff_layout_write_prepare_common(task, hdr))
1265                 return;
1266
1267         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1268                         hdr->args.lock_context, FMODE_WRITE) == -EIO)
1269                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1270 }
1271
1272 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1273 {
1274         struct nfs_pgio_header *hdr = data;
1275
1276         nfs4_ff_layout_stat_io_end_write(task,
1277                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1278                         hdr->args.count, hdr->res.count,
1279                         hdr->res.verf->committed);
1280
1281         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1282             task->tk_status == 0) {
1283                 nfs4_sequence_done(task, &hdr->res.seq_res);
1284                 return;
1285         }
1286
1287         /* Note this may cause RPC to be resent */
1288         hdr->mds_ops->rpc_call_done(task, hdr);
1289 }
1290
1291 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1292 {
1293         struct nfs_pgio_header *hdr = data;
1294
1295         rpc_count_iostats_metrics(task,
1296             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1297 }
1298
1299 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1300                 struct nfs_commit_data *cdata)
1301 {
1302         nfs4_ff_layout_stat_io_start_write(
1303                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1304                         0);
1305 }
1306
1307 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1308 {
1309         ff_layout_commit_prepare_common(task, data);
1310         rpc_call_start(task);
1311 }
1312
1313 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1314 {
1315         struct nfs_commit_data *wdata = data;
1316
1317         if (ff_layout_setup_sequence(wdata->ds_clp,
1318                                  &wdata->args.seq_args,
1319                                  &wdata->res.seq_res,
1320                                  task))
1321                 return;
1322         ff_layout_commit_prepare_common(task, data);
1323 }
1324
1325 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1326 {
1327         struct nfs_commit_data *cdata = data;
1328         struct nfs_page *req;
1329         __u64 count = 0;
1330
1331         if (task->tk_status == 0) {
1332                 list_for_each_entry(req, &cdata->pages, wb_list)
1333                         count += req->wb_bytes;
1334         }
1335
1336         nfs4_ff_layout_stat_io_end_write(task,
1337                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1338                         count, count, NFS_FILE_SYNC);
1339
1340         pnfs_generic_write_commit_done(task, data);
1341 }
1342
1343 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1344 {
1345         struct nfs_commit_data *cdata = data;
1346
1347         rpc_count_iostats_metrics(task,
1348             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1349 }
1350
1351 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1352         .rpc_call_prepare = ff_layout_read_prepare_v3,
1353         .rpc_call_done = ff_layout_read_call_done,
1354         .rpc_count_stats = ff_layout_read_count_stats,
1355         .rpc_release = pnfs_generic_rw_release,
1356 };
1357
1358 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1359         .rpc_call_prepare = ff_layout_read_prepare_v4,
1360         .rpc_call_done = ff_layout_read_call_done,
1361         .rpc_count_stats = ff_layout_read_count_stats,
1362         .rpc_release = pnfs_generic_rw_release,
1363 };
1364
1365 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1366         .rpc_call_prepare = ff_layout_write_prepare_v3,
1367         .rpc_call_done = ff_layout_write_call_done,
1368         .rpc_count_stats = ff_layout_write_count_stats,
1369         .rpc_release = pnfs_generic_rw_release,
1370 };
1371
1372 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1373         .rpc_call_prepare = ff_layout_write_prepare_v4,
1374         .rpc_call_done = ff_layout_write_call_done,
1375         .rpc_count_stats = ff_layout_write_count_stats,
1376         .rpc_release = pnfs_generic_rw_release,
1377 };
1378
1379 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1380         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1381         .rpc_call_done = ff_layout_commit_done,
1382         .rpc_count_stats = ff_layout_commit_count_stats,
1383         .rpc_release = pnfs_generic_commit_release,
1384 };
1385
1386 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1387         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1388         .rpc_call_done = ff_layout_commit_done,
1389         .rpc_count_stats = ff_layout_commit_count_stats,
1390         .rpc_release = pnfs_generic_commit_release,
1391 };
1392
1393 static enum pnfs_try_status
1394 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1395 {
1396         struct pnfs_layout_segment *lseg = hdr->lseg;
1397         struct nfs4_pnfs_ds *ds;
1398         struct rpc_clnt *ds_clnt;
1399         struct rpc_cred *ds_cred;
1400         loff_t offset = hdr->args.offset;
1401         u32 idx = hdr->pgio_mirror_idx;
1402         int vers;
1403         struct nfs_fh *fh;
1404
1405         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
1406                 __func__, hdr->inode->i_ino,
1407                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1408
1409         ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
1410         if (!ds)
1411                 goto out_failed;
1412
1413         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1414                                                    hdr->inode);
1415         if (IS_ERR(ds_clnt))
1416                 goto out_failed;
1417
1418         ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1419         if (IS_ERR(ds_cred))
1420                 goto out_failed;
1421
1422         vers = nfs4_ff_layout_ds_version(lseg, idx);
1423
1424         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1425                 ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count), vers);
1426
1427         atomic_inc(&ds->ds_clp->cl_count);
1428         hdr->ds_clp = ds->ds_clp;
1429         fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1430         if (fh)
1431                 hdr->args.fh = fh;
1432         /*
1433          * Note that if we ever decide to split across DSes,
1434          * then we may need to handle dense-like offsets.
1435          */
1436         hdr->args.offset = offset;
1437         hdr->mds_offset = offset;
1438
1439         /* Perform an asynchronous read to ds */
1440         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1441                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1442                                       &ff_layout_read_call_ops_v4,
1443                           0, RPC_TASK_SOFTCONN);
1444
1445         return PNFS_ATTEMPTED;
1446
1447 out_failed:
1448         if (ff_layout_has_available_ds(lseg))
1449                 return PNFS_TRY_AGAIN;
1450         return PNFS_NOT_ATTEMPTED;
1451 }
1452
1453 /* Perform async writes. */
1454 static enum pnfs_try_status
1455 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1456 {
1457         struct pnfs_layout_segment *lseg = hdr->lseg;
1458         struct nfs4_pnfs_ds *ds;
1459         struct rpc_clnt *ds_clnt;
1460         struct rpc_cred *ds_cred;
1461         loff_t offset = hdr->args.offset;
1462         int vers;
1463         struct nfs_fh *fh;
1464         int idx = hdr->pgio_mirror_idx;
1465
1466         ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1467         if (!ds)
1468                 return PNFS_NOT_ATTEMPTED;
1469
1470         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1471                                                    hdr->inode);
1472         if (IS_ERR(ds_clnt))
1473                 return PNFS_NOT_ATTEMPTED;
1474
1475         ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1476         if (IS_ERR(ds_cred))
1477                 return PNFS_NOT_ATTEMPTED;
1478
1479         vers = nfs4_ff_layout_ds_version(lseg, idx);
1480
1481         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d vers %d\n",
1482                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1483                 offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count),
1484                 vers);
1485
1486         hdr->pgio_done_cb = ff_layout_write_done_cb;
1487         atomic_inc(&ds->ds_clp->cl_count);
1488         hdr->ds_clp = ds->ds_clp;
1489         hdr->ds_commit_idx = idx;
1490         fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1491         if (fh)
1492                 hdr->args.fh = fh;
1493
1494         /*
1495          * Note that if we ever decide to split across DSes,
1496          * then we may need to handle dense-like offsets.
1497          */
1498         hdr->args.offset = offset;
1499
1500         /* Perform an asynchronous write */
1501         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1502                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1503                                       &ff_layout_write_call_ops_v4,
1504                           sync, RPC_TASK_SOFTCONN);
1505         return PNFS_ATTEMPTED;
1506 }
1507
1508 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1509 {
1510         return i;
1511 }
1512
1513 static struct nfs_fh *
1514 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1515 {
1516         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1517
1518         /* FIXME: Assume that there is only one NFS version available
1519          * for the DS.
1520          */
1521         return &flseg->mirror_array[i]->fh_versions[0];
1522 }
1523
1524 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1525 {
1526         struct pnfs_layout_segment *lseg = data->lseg;
1527         struct nfs4_pnfs_ds *ds;
1528         struct rpc_clnt *ds_clnt;
1529         struct rpc_cred *ds_cred;
1530         u32 idx;
1531         int vers;
1532         struct nfs_fh *fh;
1533
1534         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1535         ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1536         if (!ds)
1537                 goto out_err;
1538
1539         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1540                                                    data->inode);
1541         if (IS_ERR(ds_clnt))
1542                 goto out_err;
1543
1544         ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
1545         if (IS_ERR(ds_cred))
1546                 goto out_err;
1547
1548         vers = nfs4_ff_layout_ds_version(lseg, idx);
1549
1550         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1551                 data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count),
1552                 vers);
1553         data->commit_done_cb = ff_layout_commit_done_cb;
1554         data->cred = ds_cred;
1555         atomic_inc(&ds->ds_clp->cl_count);
1556         data->ds_clp = ds->ds_clp;
1557         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1558         if (fh)
1559                 data->args.fh = fh;
1560
1561         return nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1562                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1563                                                &ff_layout_commit_call_ops_v4,
1564                                    how, RPC_TASK_SOFTCONN);
1565 out_err:
1566         pnfs_generic_prepare_to_resend_writes(data);
1567         pnfs_generic_commit_release(data);
1568         return -EAGAIN;
1569 }
1570
1571 static int
1572 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1573                            int how, struct nfs_commit_info *cinfo)
1574 {
1575         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1576                                             ff_layout_initiate_commit);
1577 }
1578
1579 static struct pnfs_ds_commit_info *
1580 ff_layout_get_ds_info(struct inode *inode)
1581 {
1582         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1583
1584         if (layout == NULL)
1585                 return NULL;
1586
1587         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1588 }
1589
1590 static void
1591 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1592 {
1593         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1594                                                   id_node));
1595 }
1596
1597 static int ff_layout_encode_ioerr(struct nfs4_flexfile_layout *flo,
1598                                   struct xdr_stream *xdr,
1599                                   const struct nfs4_layoutreturn_args *args)
1600 {
1601         struct pnfs_layout_hdr *hdr = &flo->generic_hdr;
1602         __be32 *start;
1603         int count = 0, ret = 0;
1604
1605         start = xdr_reserve_space(xdr, 4);
1606         if (unlikely(!start))
1607                 return -E2BIG;
1608
1609         /* This assume we always return _ALL_ layouts */
1610         spin_lock(&hdr->plh_inode->i_lock);
1611         ret = ff_layout_encode_ds_ioerr(flo, xdr, &count, &args->range);
1612         spin_unlock(&hdr->plh_inode->i_lock);
1613
1614         *start = cpu_to_be32(count);
1615
1616         return ret;
1617 }
1618
1619 /* report nothing for now */
1620 static void ff_layout_encode_iostats(struct nfs4_flexfile_layout *flo,
1621                                      struct xdr_stream *xdr,
1622                                      const struct nfs4_layoutreturn_args *args)
1623 {
1624         __be32 *p;
1625
1626         p = xdr_reserve_space(xdr, 4);
1627         if (likely(p))
1628                 *p = cpu_to_be32(0);
1629 }
1630
1631 static struct nfs4_deviceid_node *
1632 ff_layout_alloc_deviceid_node(struct nfs_server *server,
1633                               struct pnfs_device *pdev, gfp_t gfp_flags)
1634 {
1635         struct nfs4_ff_layout_ds *dsaddr;
1636
1637         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
1638         if (!dsaddr)
1639                 return NULL;
1640         return &dsaddr->id_node;
1641 }
1642
1643 static void
1644 ff_layout_encode_layoutreturn(struct pnfs_layout_hdr *lo,
1645                               struct xdr_stream *xdr,
1646                               const struct nfs4_layoutreturn_args *args)
1647 {
1648         struct nfs4_flexfile_layout *flo = FF_LAYOUT_FROM_HDR(lo);
1649         __be32 *start;
1650
1651         dprintk("%s: Begin\n", __func__);
1652         start = xdr_reserve_space(xdr, 4);
1653         BUG_ON(!start);
1654
1655         if (ff_layout_encode_ioerr(flo, xdr, args))
1656                 goto out;
1657
1658         ff_layout_encode_iostats(flo, xdr, args);
1659 out:
1660         *start = cpu_to_be32((xdr->p - start - 1) * 4);
1661         dprintk("%s: Return\n", __func__);
1662 }
1663
1664 static int
1665 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
1666 {
1667         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
1668
1669         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
1670 }
1671
1672 static size_t
1673 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
1674                           const int buflen)
1675 {
1676         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
1677         const struct in6_addr *addr = &sin6->sin6_addr;
1678
1679         /*
1680          * RFC 4291, Section 2.2.2
1681          *
1682          * Shorthanded ANY address
1683          */
1684         if (ipv6_addr_any(addr))
1685                 return snprintf(buf, buflen, "::");
1686
1687         /*
1688          * RFC 4291, Section 2.2.2
1689          *
1690          * Shorthanded loopback address
1691          */
1692         if (ipv6_addr_loopback(addr))
1693                 return snprintf(buf, buflen, "::1");
1694
1695         /*
1696          * RFC 4291, Section 2.2.3
1697          *
1698          * Special presentation address format for mapped v4
1699          * addresses.
1700          */
1701         if (ipv6_addr_v4mapped(addr))
1702                 return snprintf(buf, buflen, "::ffff:%pI4",
1703                                         &addr->s6_addr32[3]);
1704
1705         /*
1706          * RFC 4291, Section 2.2.1
1707          */
1708         return snprintf(buf, buflen, "%pI6c", addr);
1709 }
1710
1711 /* Derived from rpc_sockaddr2uaddr */
1712 static void
1713 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
1714 {
1715         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
1716         char portbuf[RPCBIND_MAXUADDRPLEN];
1717         char addrbuf[RPCBIND_MAXUADDRLEN];
1718         char *netid;
1719         unsigned short port;
1720         int len, netid_len;
1721         __be32 *p;
1722
1723         switch (sap->sa_family) {
1724         case AF_INET:
1725                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
1726                         return;
1727                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1728                 netid = "tcp";
1729                 netid_len = 3;
1730                 break;
1731         case AF_INET6:
1732                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
1733                         return;
1734                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
1735                 netid = "tcp6";
1736                 netid_len = 4;
1737                 break;
1738         default:
1739                 /* we only support tcp and tcp6 */
1740                 WARN_ON_ONCE(1);
1741                 return;
1742         }
1743
1744         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
1745         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
1746
1747         p = xdr_reserve_space(xdr, 4 + netid_len);
1748         xdr_encode_opaque(p, netid, netid_len);
1749
1750         p = xdr_reserve_space(xdr, 4 + len);
1751         xdr_encode_opaque(p, addrbuf, len);
1752 }
1753
1754 static void
1755 ff_layout_encode_nfstime(struct xdr_stream *xdr,
1756                          ktime_t t)
1757 {
1758         struct timespec64 ts;
1759         __be32 *p;
1760
1761         p = xdr_reserve_space(xdr, 12);
1762         ts = ktime_to_timespec64(t);
1763         p = xdr_encode_hyper(p, ts.tv_sec);
1764         *p++ = cpu_to_be32(ts.tv_nsec);
1765 }
1766
1767 static void
1768 ff_layout_encode_io_latency(struct xdr_stream *xdr,
1769                             struct nfs4_ff_io_stat *stat)
1770 {
1771         __be32 *p;
1772
1773         p = xdr_reserve_space(xdr, 5 * 8);
1774         p = xdr_encode_hyper(p, stat->ops_requested);
1775         p = xdr_encode_hyper(p, stat->bytes_requested);
1776         p = xdr_encode_hyper(p, stat->ops_completed);
1777         p = xdr_encode_hyper(p, stat->bytes_completed);
1778         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
1779         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
1780         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
1781 }
1782
1783 static void
1784 ff_layout_encode_layoutstats(struct xdr_stream *xdr,
1785                              struct nfs42_layoutstat_args *args,
1786                              struct nfs42_layoutstat_devinfo *devinfo)
1787 {
1788         struct nfs4_ff_layout_mirror *mirror = devinfo->layout_private;
1789         struct nfs4_pnfs_ds_addr *da;
1790         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
1791         struct nfs_fh *fh = &mirror->fh_versions[0];
1792         __be32 *p, *start;
1793
1794         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
1795         dprintk("%s: DS %s: encoding address %s\n",
1796                 __func__, ds->ds_remotestr, da->da_remotestr);
1797         /* layoutupdate length */
1798         start = xdr_reserve_space(xdr, 4);
1799         /* netaddr4 */
1800         ff_layout_encode_netaddr(xdr, da);
1801         /* nfs_fh4 */
1802         p = xdr_reserve_space(xdr, 4 + fh->size);
1803         xdr_encode_opaque(p, fh->data, fh->size);
1804         /* ff_io_latency4 read */
1805         spin_lock(&mirror->lock);
1806         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
1807         /* ff_io_latency4 write */
1808         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
1809         spin_unlock(&mirror->lock);
1810         /* nfstime4 */
1811         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
1812         /* bool */
1813         p = xdr_reserve_space(xdr, 4);
1814         *p = cpu_to_be32(false);
1815
1816         *start = cpu_to_be32((xdr->p - start - 1) * 4);
1817 }
1818
1819 static bool
1820 ff_layout_mirror_prepare_stats(struct nfs42_layoutstat_args *args,
1821                                struct pnfs_layout_segment *pls,
1822                                int *dev_count, int dev_limit)
1823 {
1824         struct nfs4_ff_layout_mirror *mirror;
1825         struct nfs4_deviceid_node *dev;
1826         struct nfs42_layoutstat_devinfo *devinfo;
1827         int i;
1828
1829         for (i = 0; i <= FF_LAYOUT_MIRROR_COUNT(pls); i++) {
1830                 if (*dev_count >= dev_limit)
1831                         break;
1832                 mirror = FF_LAYOUT_COMP(pls, i);
1833                 if (!mirror || !mirror->mirror_ds)
1834                         continue;
1835                 dev = FF_LAYOUT_DEVID_NODE(pls, i);
1836                 devinfo = &args->devinfo[*dev_count];
1837                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
1838                 devinfo->offset = pls->pls_range.offset;
1839                 devinfo->length = pls->pls_range.length;
1840                 /* well, we don't really know if IO is continuous or not! */
1841                 devinfo->read_count = mirror->read_stat.io_stat.bytes_completed;
1842                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
1843                 devinfo->write_count = mirror->write_stat.io_stat.bytes_completed;
1844                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
1845                 devinfo->layout_type = LAYOUT_FLEX_FILES;
1846                 devinfo->layoutstats_encode = ff_layout_encode_layoutstats;
1847                 devinfo->layout_private = mirror;
1848                 /* lseg refcount put in cleanup_layoutstats */
1849                 pnfs_get_lseg(pls);
1850
1851                 ++(*dev_count);
1852         }
1853
1854         return *dev_count < dev_limit;
1855 }
1856
1857 static int
1858 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
1859 {
1860         struct pnfs_layout_segment *pls;
1861         int dev_count = 0;
1862
1863         spin_lock(&args->inode->i_lock);
1864         list_for_each_entry(pls, &NFS_I(args->inode)->layout->plh_segs, pls_list) {
1865                 dev_count += FF_LAYOUT_MIRROR_COUNT(pls);
1866         }
1867         spin_unlock(&args->inode->i_lock);
1868         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
1869         if (dev_count > PNFS_LAYOUTSTATS_MAXDEV) {
1870                 dprintk("%s: truncating devinfo to limit (%d:%d)\n",
1871                         __func__, dev_count, PNFS_LAYOUTSTATS_MAXDEV);
1872                 dev_count = PNFS_LAYOUTSTATS_MAXDEV;
1873         }
1874         args->devinfo = kmalloc(dev_count * sizeof(*args->devinfo), GFP_KERNEL);
1875         if (!args->devinfo)
1876                 return -ENOMEM;
1877
1878         dev_count = 0;
1879         spin_lock(&args->inode->i_lock);
1880         list_for_each_entry(pls, &NFS_I(args->inode)->layout->plh_segs, pls_list) {
1881                 if (!ff_layout_mirror_prepare_stats(args, pls, &dev_count,
1882                                                     PNFS_LAYOUTSTATS_MAXDEV)) {
1883                         break;
1884                 }
1885         }
1886         spin_unlock(&args->inode->i_lock);
1887         args->num_dev = dev_count;
1888
1889         return 0;
1890 }
1891
1892 static void
1893 ff_layout_cleanup_layoutstats(struct nfs42_layoutstat_data *data)
1894 {
1895         struct nfs4_ff_layout_mirror *mirror;
1896         int i;
1897
1898         for (i = 0; i < data->args.num_dev; i++) {
1899                 mirror = data->args.devinfo[i].layout_private;
1900                 data->args.devinfo[i].layout_private = NULL;
1901                 pnfs_put_lseg(mirror->lseg);
1902         }
1903 }
1904
1905 static struct pnfs_layoutdriver_type flexfilelayout_type = {
1906         .id                     = LAYOUT_FLEX_FILES,
1907         .name                   = "LAYOUT_FLEX_FILES",
1908         .owner                  = THIS_MODULE,
1909         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
1910         .free_layout_hdr        = ff_layout_free_layout_hdr,
1911         .alloc_lseg             = ff_layout_alloc_lseg,
1912         .free_lseg              = ff_layout_free_lseg,
1913         .pg_read_ops            = &ff_layout_pg_read_ops,
1914         .pg_write_ops           = &ff_layout_pg_write_ops,
1915         .get_ds_info            = ff_layout_get_ds_info,
1916         .free_deviceid_node     = ff_layout_free_deviceid_node,
1917         .mark_request_commit    = pnfs_layout_mark_request_commit,
1918         .clear_request_commit   = pnfs_generic_clear_request_commit,
1919         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
1920         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
1921         .commit_pagelist        = ff_layout_commit_pagelist,
1922         .read_pagelist          = ff_layout_read_pagelist,
1923         .write_pagelist         = ff_layout_write_pagelist,
1924         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
1925         .encode_layoutreturn    = ff_layout_encode_layoutreturn,
1926         .sync                   = pnfs_nfs_generic_sync,
1927         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
1928         .cleanup_layoutstats    = ff_layout_cleanup_layoutstats,
1929 };
1930
1931 static int __init nfs4flexfilelayout_init(void)
1932 {
1933         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
1934                __func__);
1935         return pnfs_register_layoutdriver(&flexfilelayout_type);
1936 }
1937
1938 static void __exit nfs4flexfilelayout_exit(void)
1939 {
1940         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
1941                __func__);
1942         pnfs_unregister_layoutdriver(&flexfilelayout_type);
1943 }
1944
1945 MODULE_ALIAS("nfs-layouttype4-4");
1946
1947 MODULE_LICENSE("GPL");
1948 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
1949
1950 module_init(nfs4flexfilelayout_init);
1951 module_exit(nfs4flexfilelayout_exit);