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 #include <linux/sched/mm.h>
  13
  14 #include <linux/sunrpc/metrics.h>
  15
  16 #include "flexfilelayout.h"
  17 #include "../nfs4session.h"
  18 #include "../nfs4idmap.h"
  19 #include "../internal.h"
  20 #include "../delegation.h"
  21 #include "../nfs4trace.h"
  22 #include "../iostat.h"
  23 #include "../nfs.h"
  24 #include "../nfs42.h"
  25
  26 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  27
  28 #define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  29 #define FF_LAYOUTRETURN_MAXERR 20
  30
  31 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
  32                 struct nfs_pgio_header *hdr);
  33 static int ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
  34                                struct nfs42_layoutstat_devinfo *devinfo,
  35                                int dev_limit);
  36 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
  37                               const struct nfs42_layoutstat_devinfo *devinfo,
  38                               struct nfs4_ff_layout_mirror *mirror);
  39
  40 static struct pnfs_layout_hdr *
  41 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  42 {
  43         struct nfs4_flexfile_layout *ffl;
  44
  45         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  46         if (ffl) {
  47                 INIT_LIST_HEAD(&ffl->error_list);
  48                 INIT_LIST_HEAD(&ffl->mirrors);
  49                 ffl->last_report_time = ktime_get();
  50                 return &ffl->generic_hdr;
  51         } else
  52                 return NULL;
  53 }
  54
  55 static void
  56 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  57 {
  58         struct nfs4_ff_layout_ds_err *err, *n;
  59
  60         list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  61                                  list) {
  62                 list_del(&err->list);
  63                 kfree(err);
  64         }
  65         kfree(FF_LAYOUT_FROM_HDR(lo));
  66 }
  67
  68 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  69 {
  70         __be32 *p;
  71
  72         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  73         if (unlikely(p == NULL))
  74                 return -ENOBUFS;
  75         stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  76         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  77         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  78                 p[0], p[1], p[2], p[3]);
  79         return 0;
  80 }
  81
  82 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  83 {
  84         __be32 *p;
  85
  86         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  87         if (unlikely(!p))
  88                 return -ENOBUFS;
  89         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  90         nfs4_print_deviceid(devid);
  91         return 0;
  92 }
  93
  94 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  95 {
  96         __be32 *p;
  97
  98         p = xdr_inline_decode(xdr, 4);
  99         if (unlikely(!p))
 100                 return -ENOBUFS;
 101         fh->size = be32_to_cpup(p++);
 102         if (fh->size > sizeof(struct nfs_fh)) {
 103                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
 104                        fh->size);
 105                 return -EOVERFLOW;
 106         }
 107         /* fh.data */
 108         p = xdr_inline_decode(xdr, fh->size);
 109         if (unlikely(!p))
 110                 return -ENOBUFS;
 111         memcpy(&fh->data, p, fh->size);
 112         dprintk("%s: fh len %d\n", __func__, fh->size);
 113
 114         return 0;
 115 }
 116
 117 /*
 118  * Currently only stringified uids and gids are accepted.
 119  * I.e., kerberos is not supported to the DSes, so no pricipals.
 120  *
 121  * That means that one common function will suffice, but when
 122  * principals are added, this should be split to accomodate
 123  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 124  */
 125 static int
 126 decode_name(struct xdr_stream *xdr, u32 *id)
 127 {
 128         __be32 *p;
 129         int len;
 130
 131         /* opaque_length(4)*/
 132         p = xdr_inline_decode(xdr, 4);
 133         if (unlikely(!p))
 134                 return -ENOBUFS;
 135         len = be32_to_cpup(p++);
 136         if (len < 0)
 137                 return -EINVAL;
 138
 139         dprintk("%s: len %u\n", __func__, len);
 140
 141         /* opaque body */
 142         p = xdr_inline_decode(xdr, len);
 143         if (unlikely(!p))
 144                 return -ENOBUFS;
 145
 146         if (!nfs_map_string_to_numeric((char *)p, len, id))
 147                 return -EINVAL;
 148
 149         return 0;
 150 }
 151
 152 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 153                 const struct nfs4_ff_layout_mirror *m2)
 154 {
 155         int i, j;
 156
 157         if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 158                 return false;
 159         for (i = 0; i < m1->fh_versions_cnt; i++) {
 160                 bool found_fh = false;
 161                 for (j = 0; j < m2->fh_versions_cnt; j++) {
 162                         if (nfs_compare_fh(&m1->fh_versions[i],
 163                                         &m2->fh_versions[j]) == 0) {
 164                                 found_fh = true;
 165                                 break;
 166                         }
 167                 }
 168                 if (!found_fh)
 169                         return false;
 170         }
 171         return true;
 172 }
 173
 174 static struct nfs4_ff_layout_mirror *
 175 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 176                 struct nfs4_ff_layout_mirror *mirror)
 177 {
 178         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 179         struct nfs4_ff_layout_mirror *pos;
 180         struct inode *inode = lo->plh_inode;
 181
 182         spin_lock(&inode->i_lock);
 183         list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 184                 if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
 185                         continue;
 186                 if (!ff_mirror_match_fh(mirror, pos))
 187                         continue;
 188                 if (refcount_inc_not_zero(&pos->ref)) {
 189                         spin_unlock(&inode->i_lock);
 190                         return pos;
 191                 }
 192         }
 193         list_add(&mirror->mirrors, &ff_layout->mirrors);
 194         mirror->layout = lo;
 195         spin_unlock(&inode->i_lock);
 196         return mirror;
 197 }
 198
 199 static void
 200 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 201 {
 202         struct inode *inode;
 203         if (mirror->layout == NULL)
 204                 return;
 205         inode = mirror->layout->plh_inode;
 206         spin_lock(&inode->i_lock);
 207         list_del(&mirror->mirrors);
 208         spin_unlock(&inode->i_lock);
 209         mirror->layout = NULL;
 210 }
 211
 212 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 213 {
 214         struct nfs4_ff_layout_mirror *mirror;
 215
 216         mirror = kzalloc(sizeof(*mirror), gfp_flags);
 217         if (mirror != NULL) {
 218                 spin_lock_init(&mirror->lock);
 219                 refcount_set(&mirror->ref, 1);
 220                 INIT_LIST_HEAD(&mirror->mirrors);
 221         }
 222         return mirror;
 223 }
 224
 225 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 226 {
 227         const struct cred       *cred;
 228
 229         ff_layout_remove_mirror(mirror);
 230         kfree(mirror->fh_versions);
 231         cred = rcu_access_pointer(mirror->ro_cred);
 232         put_cred(cred);
 233         cred = rcu_access_pointer(mirror->rw_cred);
 234         put_cred(cred);
 235         nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 236         kfree(mirror);
 237 }
 238
 239 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 240 {
 241         if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
 242                 ff_layout_free_mirror(mirror);
 243 }
 244
 245 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 246 {
 247         int i;
 248
 249         if (fls->mirror_array) {
 250                 for (i = 0; i < fls->mirror_array_cnt; i++) {
 251                         /* normally mirror_ds is freed in
 252                          * .free_deviceid_node but we still do it here
 253                          * for .alloc_lseg error path */
 254                         ff_layout_put_mirror(fls->mirror_array[i]);
 255                 }
 256                 kfree(fls->mirror_array);
 257                 fls->mirror_array = NULL;
 258         }
 259 }
 260
 261 static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 262 {
 263         int ret = 0;
 264
 265         dprintk("--> %s\n", __func__);
 266
 267         /* FIXME: remove this check when layout segment support is added */
 268         if (lgr->range.offset != 0 ||
 269             lgr->range.length != NFS4_MAX_UINT64) {
 270                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 271                         __func__);
 272                 ret = -EINVAL;
 273         }
 274
 275         dprintk("--> %s returns %d\n", __func__, ret);
 276         return ret;
 277 }
 278
 279 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 280 {
 281         if (fls) {
 282                 ff_layout_free_mirror_array(fls);
 283                 kfree(fls);
 284         }
 285 }
 286
 287 static bool
 288 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 289                 const struct pnfs_layout_range *l2)
 290 {
 291         u64 end1, end2;
 292
 293         if (l1->iomode != l2->iomode)
 294                 return l1->iomode != IOMODE_READ;
 295         end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 296         end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 297         if (end1 < l2->offset)
 298                 return false;
 299         if (end2 < l1->offset)
 300                 return true;
 301         return l2->offset <= l1->offset;
 302 }
 303
 304 static bool
 305 ff_lseg_merge(struct pnfs_layout_segment *new,
 306                 struct pnfs_layout_segment *old)
 307 {
 308         u64 new_end, old_end;
 309
 310         if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 311                 return false;
 312         if (new->pls_range.iomode != old->pls_range.iomode)
 313                 return false;
 314         old_end = pnfs_calc_offset_end(old->pls_range.offset,
 315                         old->pls_range.length);
 316         if (old_end < new->pls_range.offset)
 317                 return false;
 318         new_end = pnfs_calc_offset_end(new->pls_range.offset,
 319                         new->pls_range.length);
 320         if (new_end < old->pls_range.offset)
 321                 return false;
 322
 323         /* Mergeable: copy info from 'old' to 'new' */
 324         if (new_end < old_end)
 325                 new_end = old_end;
 326         if (new->pls_range.offset < old->pls_range.offset)
 327                 new->pls_range.offset = old->pls_range.offset;
 328         new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 329                         new_end);
 330         if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 331                 set_bit(NFS_LSEG_ROC, &new->pls_flags);
 332         return true;
 333 }
 334
 335 static void
 336 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 337                 struct pnfs_layout_segment *lseg,
 338                 struct list_head *free_me)
 339 {
 340         pnfs_generic_layout_insert_lseg(lo, lseg,
 341                         ff_lseg_range_is_after,
 342                         ff_lseg_merge,
 343                         free_me);
 344 }
 345
 346 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 347 {
 348         int i, j;
 349
 350         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 351                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 352                         if (fls->mirror_array[i]->efficiency <
 353                             fls->mirror_array[j]->efficiency)
 354                                 swap(fls->mirror_array[i],
 355                                      fls->mirror_array[j]);
 356         }
 357 }
 358
 359 static struct pnfs_layout_segment *
 360 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 361                      struct nfs4_layoutget_res *lgr,
 362                      gfp_t gfp_flags)
 363 {
 364         struct pnfs_layout_segment *ret;
 365         struct nfs4_ff_layout_segment *fls = NULL;
 366         struct xdr_stream stream;
 367         struct xdr_buf buf;
 368         struct page *scratch;
 369         u64 stripe_unit;
 370         u32 mirror_array_cnt;
 371         __be32 *p;
 372         int i, rc;
 373
 374         dprintk("--> %s\n", __func__);
 375         scratch = alloc_page(gfp_flags);
 376         if (!scratch)
 377                 return ERR_PTR(-ENOMEM);
 378
 379         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 380                               lgr->layoutp->len);
 381         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 382
 383         /* stripe unit and mirror_array_cnt */
 384         rc = -EIO;
 385         p = xdr_inline_decode(&stream, 8 + 4);
 386         if (!p)
 387                 goto out_err_free;
 388
 389         p = xdr_decode_hyper(p, &stripe_unit);
 390         mirror_array_cnt = be32_to_cpup(p++);
 391         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 392                 stripe_unit, mirror_array_cnt);
 393
 394         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 395             mirror_array_cnt == 0)
 396                 goto out_err_free;
 397
 398         rc = -ENOMEM;
 399         fls = kzalloc(sizeof(*fls), gfp_flags);
 400         if (!fls)
 401                 goto out_err_free;
 402
 403         fls->mirror_array_cnt = mirror_array_cnt;
 404         fls->stripe_unit = stripe_unit;
 405         fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 406                                     sizeof(fls->mirror_array[0]), gfp_flags);
 407         if (fls->mirror_array == NULL)
 408                 goto out_err_free;
 409
 410         for (i = 0; i < fls->mirror_array_cnt; i++) {
 411                 struct nfs4_ff_layout_mirror *mirror;
 412                 struct cred *kcred;
 413                 const struct cred *cred;
 414                 kuid_t uid;
 415                 kgid_t gid;
 416                 u32 ds_count, fh_count, id;
 417                 int j;
 418
 419                 rc = -EIO;
 420                 p = xdr_inline_decode(&stream, 4);
 421                 if (!p)
 422                         goto out_err_free;
 423                 ds_count = be32_to_cpup(p);
 424
 425                 /* FIXME: allow for striping? */
 426                 if (ds_count != 1)
 427                         goto out_err_free;
 428
 429                 fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 430                 if (fls->mirror_array[i] == NULL) {
 431                         rc = -ENOMEM;
 432                         goto out_err_free;
 433                 }
 434
 435                 fls->mirror_array[i]->ds_count = ds_count;
 436
 437                 /* deviceid */
 438                 rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
 439                 if (rc)
 440                         goto out_err_free;
 441
 442                 /* efficiency */
 443                 rc = -EIO;
 444                 p = xdr_inline_decode(&stream, 4);
 445                 if (!p)
 446                         goto out_err_free;
 447                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 448
 449                 /* stateid */
 450                 rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 451                 if (rc)
 452                         goto out_err_free;
 453
 454                 /* fh */
 455                 rc = -EIO;
 456                 p = xdr_inline_decode(&stream, 4);
 457                 if (!p)
 458                         goto out_err_free;
 459                 fh_count = be32_to_cpup(p);
 460
 461                 fls->mirror_array[i]->fh_versions =
 462                         kcalloc(fh_count, sizeof(struct nfs_fh),
 463                                 gfp_flags);
 464                 if (fls->mirror_array[i]->fh_versions == NULL) {
 465                         rc = -ENOMEM;
 466                         goto out_err_free;
 467                 }
 468
 469                 for (j = 0; j < fh_count; j++) {
 470                         rc = decode_nfs_fh(&stream,
 471                                            &fls->mirror_array[i]->fh_versions[j]);
 472                         if (rc)
 473                                 goto out_err_free;
 474                 }
 475
 476                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 477
 478                 /* user */
 479                 rc = decode_name(&stream, &id);
 480                 if (rc)
 481                         goto out_err_free;
 482
 483                 uid = make_kuid(&init_user_ns, id);
 484
 485                 /* group */
 486                 rc = decode_name(&stream, &id);
 487                 if (rc)
 488                         goto out_err_free;
 489
 490                 gid = make_kgid(&init_user_ns, id);
 491
 492                 if (gfp_flags & __GFP_FS)
 493                         kcred = prepare_kernel_cred(NULL);
 494                 else {
 495                         unsigned int nofs_flags = memalloc_nofs_save();
 496                         kcred = prepare_kernel_cred(NULL);
 497                         memalloc_nofs_restore(nofs_flags);
 498                 }
 499                 rc = -ENOMEM;
 500                 if (!kcred)
 501                         goto out_err_free;
 502                 kcred->fsuid = uid;
 503                 kcred->fsgid = gid;
 504                 cred = kcred;
 505
 506                 if (lgr->range.iomode == IOMODE_READ)
 507                         rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 508                 else
 509                         rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 510
 511                 mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 512                 if (mirror != fls->mirror_array[i]) {
 513                         /* swap cred ptrs so free_mirror will clean up old */
 514                         if (lgr->range.iomode == IOMODE_READ) {
 515                                 cred = xchg(&mirror->ro_cred, cred);
 516                                 rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 517                         } else {
 518                                 cred = xchg(&mirror->rw_cred, cred);
 519                                 rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 520                         }
 521                         ff_layout_free_mirror(fls->mirror_array[i]);
 522                         fls->mirror_array[i] = mirror;
 523                 }
 524
 525                 dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 526                         lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 527                         from_kuid(&init_user_ns, uid),
 528                         from_kgid(&init_user_ns, gid));
 529         }
 530
 531         p = xdr_inline_decode(&stream, 4);
 532         if (!p)
 533                 goto out_sort_mirrors;
 534         fls->flags = be32_to_cpup(p);
 535
 536         p = xdr_inline_decode(&stream, 4);
 537         if (!p)
 538                 goto out_sort_mirrors;
 539         for (i=0; i < fls->mirror_array_cnt; i++)
 540                 fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 541
 542 out_sort_mirrors:
 543         ff_layout_sort_mirrors(fls);
 544         rc = ff_layout_check_layout(lgr);
 545         if (rc)
 546                 goto out_err_free;
 547         ret = &fls->generic_hdr;
 548         dprintk("<-- %s (success)\n", __func__);
 549 out_free_page:
 550         __free_page(scratch);
 551         return ret;
 552 out_err_free:
 553         _ff_layout_free_lseg(fls);
 554         ret = ERR_PTR(rc);
 555         dprintk("<-- %s (%d)\n", __func__, rc);
 556         goto out_free_page;
 557 }
 558
 559 static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 560 {
 561         struct pnfs_layout_segment *lseg;
 562
 563         list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 564                 if (lseg->pls_range.iomode == IOMODE_RW)
 565                         return true;
 566
 567         return false;
 568 }
 569
 570 static void
 571 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 572 {
 573         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 574
 575         dprintk("--> %s\n", __func__);
 576
 577         if (lseg->pls_range.iomode == IOMODE_RW) {
 578                 struct nfs4_flexfile_layout *ffl;
 579                 struct inode *inode;
 580
 581                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 582                 inode = ffl->generic_hdr.plh_inode;
 583                 spin_lock(&inode->i_lock);
 584                 if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 585                         ffl->commit_info.nbuckets = 0;
 586                         kfree(ffl->commit_info.buckets);
 587                         ffl->commit_info.buckets = NULL;
 588                 }
 589                 spin_unlock(&inode->i_lock);
 590         }
 591         _ff_layout_free_lseg(fls);
 592 }
 593
 594 /* Return 1 until we have multiple lsegs support */
 595 static int
 596 ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 597 {
 598         return 1;
 599 }
 600
 601 static void
 602 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 603 {
 604         /* first IO request? */
 605         if (atomic_inc_return(&timer->n_ops) == 1) {
 606                 timer->start_time = now;
 607         }
 608 }
 609
 610 static ktime_t
 611 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 612 {
 613         ktime_t start;
 614
 615         if (atomic_dec_return(&timer->n_ops) < 0)
 616                 WARN_ON_ONCE(1);
 617
 618         start = timer->start_time;
 619         timer->start_time = now;
 620         return ktime_sub(now, start);
 621 }
 622
 623 static bool
 624 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 625                             struct nfs4_ff_layoutstat *layoutstat,
 626                             ktime_t now)
 627 {
 628         s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 629         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 630
 631         nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 632         if (!mirror->start_time)
 633                 mirror->start_time = now;
 634         if (mirror->report_interval != 0)
 635                 report_interval = (s64)mirror->report_interval * 1000LL;
 636         else if (layoutstats_timer != 0)
 637                 report_interval = (s64)layoutstats_timer * 1000LL;
 638         if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 639                         report_interval) {
 640                 ffl->last_report_time = now;
 641                 return true;
 642         }
 643
 644         return false;
 645 }
 646
 647 static void
 648 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 649                 __u64 requested)
 650 {
 651         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 652
 653         iostat->ops_requested++;
 654         iostat->bytes_requested += requested;
 655 }
 656
 657 static void
 658 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 659                 __u64 requested,
 660                 __u64 completed,
 661                 ktime_t time_completed,
 662                 ktime_t time_started)
 663 {
 664         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 665         ktime_t completion_time = ktime_sub(time_completed, time_started);
 666         ktime_t timer;
 667
 668         iostat->ops_completed++;
 669         iostat->bytes_completed += completed;
 670         iostat->bytes_not_delivered += requested - completed;
 671
 672         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 673         iostat->total_busy_time =
 674                         ktime_add(iostat->total_busy_time, timer);
 675         iostat->aggregate_completion_time =
 676                         ktime_add(iostat->aggregate_completion_time,
 677                                         completion_time);
 678 }
 679
 680 static void
 681 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 682                 struct nfs4_ff_layout_mirror *mirror,
 683                 __u64 requested, ktime_t now)
 684 {
 685         bool report;
 686
 687         spin_lock(&mirror->lock);
 688         report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 689         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 690         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 691         spin_unlock(&mirror->lock);
 692
 693         if (report)
 694                 pnfs_report_layoutstat(inode, GFP_KERNEL);
 695 }
 696
 697 static void
 698 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 699                 struct nfs4_ff_layout_mirror *mirror,
 700                 __u64 requested,
 701                 __u64 completed)
 702 {
 703         spin_lock(&mirror->lock);
 704         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 705                         requested, completed,
 706                         ktime_get(), task->tk_start);
 707         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 708         spin_unlock(&mirror->lock);
 709 }
 710
 711 static void
 712 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 713                 struct nfs4_ff_layout_mirror *mirror,
 714                 __u64 requested, ktime_t now)
 715 {
 716         bool report;
 717
 718         spin_lock(&mirror->lock);
 719         report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 720         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 721         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 722         spin_unlock(&mirror->lock);
 723
 724         if (report)
 725                 pnfs_report_layoutstat(inode, GFP_NOIO);
 726 }
 727
 728 static void
 729 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 730                 struct nfs4_ff_layout_mirror *mirror,
 731                 __u64 requested,
 732                 __u64 completed,
 733                 enum nfs3_stable_how committed)
 734 {
 735         if (committed == NFS_UNSTABLE)
 736                 requested = completed = 0;
 737
 738         spin_lock(&mirror->lock);
 739         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 740                         requested, completed, ktime_get(), task->tk_start);
 741         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 742         spin_unlock(&mirror->lock);
 743 }
 744
 745 static int
 746 ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 747                             struct nfs_commit_info *cinfo,
 748                             gfp_t gfp_flags)
 749 {
 750         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 751         struct pnfs_commit_bucket *buckets;
 752         int size;
 753
 754         if (cinfo->ds->nbuckets != 0) {
 755                 /* This assumes there is only one RW lseg per file.
 756                  * To support multiple lseg per file, we need to
 757                  * change struct pnfs_commit_bucket to allow dynamic
 758                  * increasing nbuckets.
 759                  */
 760                 return 0;
 761         }
 762
 763         size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 764
 765         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 766                           gfp_flags);
 767         if (!buckets)
 768                 return -ENOMEM;
 769         else {
 770                 int i;
 771
 772                 spin_lock(&cinfo->inode->i_lock);
 773                 if (cinfo->ds->nbuckets != 0)
 774                         kfree(buckets);
 775                 else {
 776                         cinfo->ds->buckets = buckets;
 777                         cinfo->ds->nbuckets = size;
 778                         for (i = 0; i < size; i++) {
 779                                 INIT_LIST_HEAD(&buckets[i].written);
 780                                 INIT_LIST_HEAD(&buckets[i].committing);
 781                                 /* mark direct verifier as unset */
 782                                 buckets[i].direct_verf.committed =
 783                                         NFS_INVALID_STABLE_HOW;
 784                         }
 785                 }
 786                 spin_unlock(&cinfo->inode->i_lock);
 787                 return 0;
 788         }
 789 }
 790
 791 static struct nfs4_pnfs_ds *
 792 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 793                                   int start_idx,
 794                                   int *best_idx)
 795 {
 796         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 797         struct nfs4_pnfs_ds *ds;
 798         bool fail_return = false;
 799         int idx;
 800
 801         /* mirrors are sorted by efficiency */
 802         for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 803                 if (idx+1 == fls->mirror_array_cnt)
 804                         fail_return = true;
 805                 ds = nfs4_ff_layout_prepare_ds(lseg, idx, fail_return);
 806                 if (ds) {
 807                         *best_idx = idx;
 808                         return ds;
 809                 }
 810         }
 811
 812         return NULL;
 813 }
 814
 815 static void
 816 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 817                       struct nfs_page *req,
 818                       bool strict_iomode)
 819 {
 820         pnfs_put_lseg(pgio->pg_lseg);
 821         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 822                                            req->wb_context,
 823                                            0,
 824                                            NFS4_MAX_UINT64,
 825                                            IOMODE_READ,
 826                                            strict_iomode,
 827                                            GFP_KERNEL);
 828         if (IS_ERR(pgio->pg_lseg)) {
 829                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 830                 pgio->pg_lseg = NULL;
 831         }
 832 }
 833
 834 static void
 835 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 836                         struct nfs_page *req)
 837 {
 838         struct nfs_pgio_mirror *pgm;
 839         struct nfs4_ff_layout_mirror *mirror;
 840         struct nfs4_pnfs_ds *ds;
 841         int ds_idx;
 842
 843 retry:
 844         pnfs_generic_pg_check_layout(pgio);
 845         /* Use full layout for now */
 846         if (!pgio->pg_lseg) {
 847                 ff_layout_pg_get_read(pgio, req, false);
 848                 if (!pgio->pg_lseg)
 849                         goto out_nolseg;
 850         }
 851         if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 852                 ff_layout_pg_get_read(pgio, req, true);
 853                 if (!pgio->pg_lseg)
 854                         goto out_nolseg;
 855         }
 856
 857         ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 858         if (!ds) {
 859                 if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 860                         goto out_mds;
 861                 pnfs_put_lseg(pgio->pg_lseg);
 862                 pgio->pg_lseg = NULL;
 863                 /* Sleep for 1 second before retrying */
 864                 ssleep(1);
 865                 goto retry;
 866         }
 867
 868         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 869
 870         pgio->pg_mirror_idx = ds_idx;
 871
 872         /* read always uses only one mirror - idx 0 for pgio layer */
 873         pgm = &pgio->pg_mirrors[0];
 874         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 875
 876         return;
 877 out_nolseg:
 878         if (pgio->pg_error < 0)
 879                 return;
 880 out_mds:
 881         pnfs_put_lseg(pgio->pg_lseg);
 882         pgio->pg_lseg = NULL;
 883         nfs_pageio_reset_read_mds(pgio);
 884 }
 885
 886 static void
 887 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 888                         struct nfs_page *req)
 889 {
 890         struct nfs4_ff_layout_mirror *mirror;
 891         struct nfs_pgio_mirror *pgm;
 892         struct nfs_commit_info cinfo;
 893         struct nfs4_pnfs_ds *ds;
 894         int i;
 895         int status;
 896
 897 retry:
 898         pnfs_generic_pg_check_layout(pgio);
 899         if (!pgio->pg_lseg) {
 900                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 901                                                    req->wb_context,
 902                                                    0,
 903                                                    NFS4_MAX_UINT64,
 904                                                    IOMODE_RW,
 905                                                    false,
 906                                                    GFP_NOFS);
 907                 if (IS_ERR(pgio->pg_lseg)) {
 908                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 909                         pgio->pg_lseg = NULL;
 910                         return;
 911                 }
 912         }
 913         /* If no lseg, fall back to write through mds */
 914         if (pgio->pg_lseg == NULL)
 915                 goto out_mds;
 916
 917         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 918         status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 919         if (status < 0)
 920                 goto out_mds;
 921
 922         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 923         if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 924             FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 925                 goto out_mds;
 926
 927         for (i = 0; i < pgio->pg_mirror_count; i++) {
 928                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
 929                 if (!ds) {
 930                         if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 931                                 goto out_mds;
 932                         pnfs_put_lseg(pgio->pg_lseg);
 933                         pgio->pg_lseg = NULL;
 934                         /* Sleep for 1 second before retrying */
 935                         ssleep(1);
 936                         goto retry;
 937                 }
 938                 pgm = &pgio->pg_mirrors[i];
 939                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 940                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 941         }
 942
 943         return;
 944
 945 out_mds:
 946         pnfs_put_lseg(pgio->pg_lseg);
 947         pgio->pg_lseg = NULL;
 948         nfs_pageio_reset_write_mds(pgio);
 949 }
 950
 951 static unsigned int
 952 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 953                                     struct nfs_page *req)
 954 {
 955         if (!pgio->pg_lseg) {
 956                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 957                                                    req->wb_context,
 958                                                    0,
 959                                                    NFS4_MAX_UINT64,
 960                                                    IOMODE_RW,
 961                                                    false,
 962                                                    GFP_NOFS);
 963                 if (IS_ERR(pgio->pg_lseg)) {
 964                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 965                         pgio->pg_lseg = NULL;
 966                         goto out;
 967                 }
 968         }
 969         if (pgio->pg_lseg)
 970                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 971
 972         /* no lseg means that pnfs is not in use, so no mirroring here */
 973         nfs_pageio_reset_write_mds(pgio);
 974 out:
 975         return 1;
 976 }
 977
 978 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 979         .pg_init = ff_layout_pg_init_read,
 980         .pg_test = pnfs_generic_pg_test,
 981         .pg_doio = pnfs_generic_pg_readpages,
 982         .pg_cleanup = pnfs_generic_pg_cleanup,
 983 };
 984
 985 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 986         .pg_init = ff_layout_pg_init_write,
 987         .pg_test = pnfs_generic_pg_test,
 988         .pg_doio = pnfs_generic_pg_writepages,
 989         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
 990         .pg_cleanup = pnfs_generic_pg_cleanup,
 991 };
 992
 993 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
 994 {
 995         struct rpc_task *task = &hdr->task;
 996
 997         pnfs_layoutcommit_inode(hdr->inode, false);
 998
 999         if (retry_pnfs) {
1000                 dprintk("%s Reset task %5u for i/o through pNFS "
1001                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1002                         hdr->task.tk_pid,
1003                         hdr->inode->i_sb->s_id,
1004                         (unsigned long long)NFS_FILEID(hdr->inode),
1005                         hdr->args.count,
1006                         (unsigned long long)hdr->args.offset);
1007
1008                 hdr->completion_ops->reschedule_io(hdr);
1009                 return;
1010         }
1011
1012         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1013                 dprintk("%s Reset task %5u for i/o through MDS "
1014                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1015                         hdr->task.tk_pid,
1016                         hdr->inode->i_sb->s_id,
1017                         (unsigned long long)NFS_FILEID(hdr->inode),
1018                         hdr->args.count,
1019                         (unsigned long long)hdr->args.offset);
1020
1021                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1022         }
1023 }
1024
1025 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1026 {
1027         struct rpc_task *task = &hdr->task;
1028
1029         pnfs_layoutcommit_inode(hdr->inode, false);
1030
1031         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1032                 dprintk("%s Reset task %5u for i/o through MDS "
1033                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1034                         hdr->task.tk_pid,
1035                         hdr->inode->i_sb->s_id,
1036                         (unsigned long long)NFS_FILEID(hdr->inode),
1037                         hdr->args.count,
1038                         (unsigned long long)hdr->args.offset);
1039
1040                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1041         }
1042 }
1043
1044 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1045                                            struct nfs4_state *state,
1046                                            struct nfs_client *clp,
1047                                            struct pnfs_layout_segment *lseg,
1048                                            int idx)
1049 {
1050         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1051         struct inode *inode = lo->plh_inode;
1052         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1053         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1054
1055         switch (task->tk_status) {
1056         case -NFS4ERR_BADSESSION:
1057         case -NFS4ERR_BADSLOT:
1058         case -NFS4ERR_BAD_HIGH_SLOT:
1059         case -NFS4ERR_DEADSESSION:
1060         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1061         case -NFS4ERR_SEQ_FALSE_RETRY:
1062         case -NFS4ERR_SEQ_MISORDERED:
1063                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1064                         "flags 0x%x\n", __func__, task->tk_status,
1065                         clp->cl_exchange_flags);
1066                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1067                 break;
1068         case -NFS4ERR_DELAY:
1069         case -NFS4ERR_GRACE:
1070                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1071                 break;
1072         case -NFS4ERR_RETRY_UNCACHED_REP:
1073                 break;
1074         /* Invalidate Layout errors */
1075         case -NFS4ERR_PNFS_NO_LAYOUT:
1076         case -ESTALE:           /* mapped NFS4ERR_STALE */
1077         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1078         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1079         case -NFS4ERR_FHEXPIRED:
1080         case -NFS4ERR_WRONG_TYPE:
1081                 dprintk("%s Invalid layout error %d\n", __func__,
1082                         task->tk_status);
1083                 /*
1084                  * Destroy layout so new i/o will get a new layout.
1085                  * Layout will not be destroyed until all current lseg
1086                  * references are put. Mark layout as invalid to resend failed
1087                  * i/o and all i/o waiting on the slot table to the MDS until
1088                  * layout is destroyed and a new valid layout is obtained.
1089                  */
1090                 pnfs_destroy_layout(NFS_I(inode));
1091                 rpc_wake_up(&tbl->slot_tbl_waitq);
1092                 goto reset;
1093         /* RPC connection errors */
1094         case -ECONNREFUSED:
1095         case -EHOSTDOWN:
1096         case -EHOSTUNREACH:
1097         case -ENETUNREACH:
1098         case -EIO:
1099         case -ETIMEDOUT:
1100         case -EPIPE:
1101                 dprintk("%s DS connection error %d\n", __func__,
1102                         task->tk_status);
1103                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1104                                 &devid->deviceid);
1105                 rpc_wake_up(&tbl->slot_tbl_waitq);
1106                 /* fall through */
1107         default:
1108                 if (ff_layout_avoid_mds_available_ds(lseg))
1109                         return -NFS4ERR_RESET_TO_PNFS;
1110 reset:
1111                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1112                         task->tk_status);
1113                 return -NFS4ERR_RESET_TO_MDS;
1114         }
1115         task->tk_status = 0;
1116         return -EAGAIN;
1117 }
1118
1119 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1120 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1121                                            struct pnfs_layout_segment *lseg,
1122                                            int idx)
1123 {
1124         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1125
1126         switch (task->tk_status) {
1127         /* File access problems. Don't mark the device as unavailable */
1128         case -EACCES:
1129         case -ESTALE:
1130         case -EISDIR:
1131         case -EBADHANDLE:
1132         case -ELOOP:
1133         case -ENOSPC:
1134                 break;
1135         case -EJUKEBOX:
1136                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1137                 goto out_retry;
1138         default:
1139                 dprintk("%s DS connection error %d\n", __func__,
1140                         task->tk_status);
1141                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1142                                 &devid->deviceid);
1143         }
1144         /* FIXME: Need to prevent infinite looping here. */
1145         return -NFS4ERR_RESET_TO_PNFS;
1146 out_retry:
1147         task->tk_status = 0;
1148         rpc_restart_call_prepare(task);
1149         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1150         return -EAGAIN;
1151 }
1152
1153 static int ff_layout_async_handle_error(struct rpc_task *task,
1154                                         struct nfs4_state *state,
1155                                         struct nfs_client *clp,
1156                                         struct pnfs_layout_segment *lseg,
1157                                         int idx)
1158 {
1159         int vers = clp->cl_nfs_mod->rpc_vers->number;
1160
1161         if (task->tk_status >= 0)
1162                 return 0;
1163
1164         /* Handle the case of an invalid layout segment */
1165         if (!pnfs_is_valid_lseg(lseg))
1166                 return -NFS4ERR_RESET_TO_PNFS;
1167
1168         switch (vers) {
1169         case 3:
1170                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1171         case 4:
1172                 return ff_layout_async_handle_error_v4(task, state, clp,
1173                                                        lseg, idx);
1174         default:
1175                 /* should never happen */
1176                 WARN_ON_ONCE(1);
1177                 return 0;
1178         }
1179 }
1180
1181 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1182                                         int idx, u64 offset, u64 length,
1183                                         u32 status, int opnum, int error)
1184 {
1185         struct nfs4_ff_layout_mirror *mirror;
1186         int err;
1187
1188         if (status == 0) {
1189                 switch (error) {
1190                 case -ETIMEDOUT:
1191                 case -EPFNOSUPPORT:
1192                 case -EPROTONOSUPPORT:
1193                 case -EOPNOTSUPP:
1194                 case -ECONNREFUSED:
1195                 case -ECONNRESET:
1196                 case -EHOSTDOWN:
1197                 case -EHOSTUNREACH:
1198                 case -ENETUNREACH:
1199                 case -EADDRINUSE:
1200                 case -ENOBUFS:
1201                 case -EPIPE:
1202                 case -EPERM:
1203                         status = NFS4ERR_NXIO;
1204                         break;
1205                 case -EACCES:
1206                         status = NFS4ERR_ACCESS;
1207                         break;
1208                 default:
1209                         return;
1210                 }
1211         }
1212
1213         switch (status) {
1214         case NFS4ERR_DELAY:
1215         case NFS4ERR_GRACE:
1216                 return;
1217         default:
1218                 break;
1219         }
1220
1221         mirror = FF_LAYOUT_COMP(lseg, idx);
1222         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1223                                        mirror, offset, length, status, opnum,
1224                                        GFP_NOIO);
1225         pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
1226         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1227 }
1228
1229 /* NFS_PROTO call done callback routines */
1230 static int ff_layout_read_done_cb(struct rpc_task *task,
1231                                 struct nfs_pgio_header *hdr)
1232 {
1233         int err;
1234
1235         trace_nfs4_pnfs_read(hdr, task->tk_status);
1236         if (task->tk_status < 0)
1237                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1238                                             hdr->args.offset, hdr->args.count,
1239                                             hdr->res.op_status, OP_READ,
1240                                             task->tk_status);
1241         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1242                                            hdr->ds_clp, hdr->lseg,
1243                                            hdr->pgio_mirror_idx);
1244
1245         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1246         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1247         switch (err) {
1248         case -NFS4ERR_RESET_TO_PNFS:
1249                 if (ff_layout_choose_best_ds_for_read(hdr->lseg,
1250                                         hdr->pgio_mirror_idx + 1,
1251                                         &hdr->pgio_mirror_idx))
1252                         goto out_eagain;
1253                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1254                 return task->tk_status;
1255         case -NFS4ERR_RESET_TO_MDS:
1256                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1257                 return task->tk_status;
1258         case -EAGAIN:
1259                 goto out_eagain;
1260         }
1261
1262         return 0;
1263 out_eagain:
1264         rpc_restart_call_prepare(task);
1265         return -EAGAIN;
1266 }
1267
1268 static bool
1269 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1270 {
1271         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1272 }
1273
1274 /*
1275  * We reference the rpc_cred of the first WRITE that triggers the need for
1276  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1277  * rfc5661 is not clear about which credential should be used.
1278  *
1279  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1280  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1281  * we always send layoutcommit after DS writes.
1282  */
1283 static void
1284 ff_layout_set_layoutcommit(struct inode *inode,
1285                 struct pnfs_layout_segment *lseg,
1286                 loff_t end_offset)
1287 {
1288         if (!ff_layout_need_layoutcommit(lseg))
1289                 return;
1290
1291         pnfs_set_layoutcommit(inode, lseg, end_offset);
1292         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1293                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1294 }
1295
1296 static bool
1297 ff_layout_device_unavailable(struct pnfs_layout_segment *lseg, int idx)
1298 {
1299         /* No mirroring for now */
1300         struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
1301
1302         return ff_layout_test_devid_unavailable(node);
1303 }
1304
1305 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1306                 struct nfs_pgio_header *hdr)
1307 {
1308         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1309                 return;
1310         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1311                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1312                         hdr->args.count,
1313                         task->tk_start);
1314 }
1315
1316 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1317                 struct nfs_pgio_header *hdr)
1318 {
1319         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1320                 return;
1321         nfs4_ff_layout_stat_io_end_read(task,
1322                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1323                         hdr->args.count,
1324                         hdr->res.count);
1325         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1326 }
1327
1328 static int ff_layout_read_prepare_common(struct rpc_task *task,
1329                                          struct nfs_pgio_header *hdr)
1330 {
1331         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1332                 rpc_exit(task, -EIO);
1333                 return -EIO;
1334         }
1335         if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1336                 rpc_exit(task, -EHOSTDOWN);
1337                 return -EAGAIN;
1338         }
1339
1340         ff_layout_read_record_layoutstats_start(task, hdr);
1341         return 0;
1342 }
1343
1344 /*
1345  * Call ops for the async read/write cases
1346  * In the case of dense layouts, the offset needs to be reset to its
1347  * original value.
1348  */
1349 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1350 {
1351         struct nfs_pgio_header *hdr = data;
1352
1353         if (ff_layout_read_prepare_common(task, hdr))
1354                 return;
1355
1356         rpc_call_start(task);
1357 }
1358
1359 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1360 {
1361         struct nfs_pgio_header *hdr = data;
1362
1363         if (nfs4_setup_sequence(hdr->ds_clp,
1364                                 &hdr->args.seq_args,
1365                                 &hdr->res.seq_res,
1366                                 task))
1367                 return;
1368
1369         ff_layout_read_prepare_common(task, hdr);
1370 }
1371
1372 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1373 {
1374         struct nfs_pgio_header *hdr = data;
1375
1376         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1377
1378         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1379             task->tk_status == 0) {
1380                 nfs4_sequence_done(task, &hdr->res.seq_res);
1381                 return;
1382         }
1383
1384         /* Note this may cause RPC to be resent */
1385         hdr->mds_ops->rpc_call_done(task, hdr);
1386 }
1387
1388 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1389 {
1390         struct nfs_pgio_header *hdr = data;
1391
1392         ff_layout_read_record_layoutstats_done(task, hdr);
1393         rpc_count_iostats_metrics(task,
1394             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1395 }
1396
1397 static void ff_layout_read_release(void *data)
1398 {
1399         struct nfs_pgio_header *hdr = data;
1400
1401         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1402         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags))
1403                 pnfs_read_resend_pnfs(hdr);
1404         else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1405                 ff_layout_reset_read(hdr);
1406         pnfs_generic_rw_release(data);
1407 }
1408
1409
1410 static int ff_layout_write_done_cb(struct rpc_task *task,
1411                                 struct nfs_pgio_header *hdr)
1412 {
1413         loff_t end_offs = 0;
1414         int err;
1415
1416         trace_nfs4_pnfs_write(hdr, task->tk_status);
1417         if (task->tk_status < 0)
1418                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1419                                             hdr->args.offset, hdr->args.count,
1420                                             hdr->res.op_status, OP_WRITE,
1421                                             task->tk_status);
1422         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1423                                            hdr->ds_clp, hdr->lseg,
1424                                            hdr->pgio_mirror_idx);
1425
1426         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1427         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1428         switch (err) {
1429         case -NFS4ERR_RESET_TO_PNFS:
1430                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1431                 return task->tk_status;
1432         case -NFS4ERR_RESET_TO_MDS:
1433                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1434                 return task->tk_status;
1435         case -EAGAIN:
1436                 return -EAGAIN;
1437         }
1438
1439         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1440             hdr->res.verf->committed == NFS_DATA_SYNC)
1441                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1442
1443         /* Note: if the write is unstable, don't set end_offs until commit */
1444         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1445
1446         /* zero out fattr since we don't care DS attr at all */
1447         hdr->fattr.valid = 0;
1448         if (task->tk_status >= 0)
1449                 nfs_writeback_update_inode(hdr);
1450
1451         return 0;
1452 }
1453
1454 static int ff_layout_commit_done_cb(struct rpc_task *task,
1455                                      struct nfs_commit_data *data)
1456 {
1457         int err;
1458
1459         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1460         if (task->tk_status < 0)
1461                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1462                                             data->args.offset, data->args.count,
1463                                             data->res.op_status, OP_COMMIT,
1464                                             task->tk_status);
1465         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1466                                            data->lseg, data->ds_commit_index);
1467
1468         switch (err) {
1469         case -NFS4ERR_RESET_TO_PNFS:
1470                 pnfs_generic_prepare_to_resend_writes(data);
1471                 return -EAGAIN;
1472         case -NFS4ERR_RESET_TO_MDS:
1473                 pnfs_generic_prepare_to_resend_writes(data);
1474                 return -EAGAIN;
1475         case -EAGAIN:
1476                 rpc_restart_call_prepare(task);
1477                 return -EAGAIN;
1478         }
1479
1480         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1481
1482         return 0;
1483 }
1484
1485 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1486                 struct nfs_pgio_header *hdr)
1487 {
1488         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1489                 return;
1490         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1491                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1492                         hdr->args.count,
1493                         task->tk_start);
1494 }
1495
1496 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1497                 struct nfs_pgio_header *hdr)
1498 {
1499         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1500                 return;
1501         nfs4_ff_layout_stat_io_end_write(task,
1502                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1503                         hdr->args.count, hdr->res.count,
1504                         hdr->res.verf->committed);
1505         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1506 }
1507
1508 static int ff_layout_write_prepare_common(struct rpc_task *task,
1509                                           struct nfs_pgio_header *hdr)
1510 {
1511         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1512                 rpc_exit(task, -EIO);
1513                 return -EIO;
1514         }
1515
1516         if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1517                 rpc_exit(task, -EHOSTDOWN);
1518                 return -EAGAIN;
1519         }
1520
1521         ff_layout_write_record_layoutstats_start(task, hdr);
1522         return 0;
1523 }
1524
1525 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1526 {
1527         struct nfs_pgio_header *hdr = data;
1528
1529         if (ff_layout_write_prepare_common(task, hdr))
1530                 return;
1531
1532         rpc_call_start(task);
1533 }
1534
1535 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1536 {
1537         struct nfs_pgio_header *hdr = data;
1538
1539         if (nfs4_setup_sequence(hdr->ds_clp,
1540                                 &hdr->args.seq_args,
1541                                 &hdr->res.seq_res,
1542                                 task))
1543                 return;
1544
1545         ff_layout_write_prepare_common(task, hdr);
1546 }
1547
1548 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1549 {
1550         struct nfs_pgio_header *hdr = data;
1551
1552         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1553             task->tk_status == 0) {
1554                 nfs4_sequence_done(task, &hdr->res.seq_res);
1555                 return;
1556         }
1557
1558         /* Note this may cause RPC to be resent */
1559         hdr->mds_ops->rpc_call_done(task, hdr);
1560 }
1561
1562 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1563 {
1564         struct nfs_pgio_header *hdr = data;
1565
1566         ff_layout_write_record_layoutstats_done(task, hdr);
1567         rpc_count_iostats_metrics(task,
1568             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1569 }
1570
1571 static void ff_layout_write_release(void *data)
1572 {
1573         struct nfs_pgio_header *hdr = data;
1574
1575         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1576         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags))
1577                 ff_layout_reset_write(hdr, true);
1578         else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1579                 ff_layout_reset_write(hdr, false);
1580         pnfs_generic_rw_release(data);
1581 }
1582
1583 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1584                 struct nfs_commit_data *cdata)
1585 {
1586         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1587                 return;
1588         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1589                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1590                         0, task->tk_start);
1591 }
1592
1593 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1594                 struct nfs_commit_data *cdata)
1595 {
1596         struct nfs_page *req;
1597         __u64 count = 0;
1598
1599         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1600                 return;
1601
1602         if (task->tk_status == 0) {
1603                 list_for_each_entry(req, &cdata->pages, wb_list)
1604                         count += req->wb_bytes;
1605         }
1606         nfs4_ff_layout_stat_io_end_write(task,
1607                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1608                         count, count, NFS_FILE_SYNC);
1609         set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1610 }
1611
1612 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1613                 struct nfs_commit_data *cdata)
1614 {
1615         ff_layout_commit_record_layoutstats_start(task, cdata);
1616 }
1617
1618 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1619 {
1620         ff_layout_commit_prepare_common(task, data);
1621         rpc_call_start(task);
1622 }
1623
1624 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1625 {
1626         struct nfs_commit_data *wdata = data;
1627
1628         if (nfs4_setup_sequence(wdata->ds_clp,
1629                                 &wdata->args.seq_args,
1630                                 &wdata->res.seq_res,
1631                                 task))
1632                 return;
1633         ff_layout_commit_prepare_common(task, data);
1634 }
1635
1636 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1637 {
1638         pnfs_generic_write_commit_done(task, data);
1639 }
1640
1641 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1642 {
1643         struct nfs_commit_data *cdata = data;
1644
1645         ff_layout_commit_record_layoutstats_done(task, cdata);
1646         rpc_count_iostats_metrics(task,
1647             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1648 }
1649
1650 static void ff_layout_commit_release(void *data)
1651 {
1652         struct nfs_commit_data *cdata = data;
1653
1654         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1655         pnfs_generic_commit_release(data);
1656 }
1657
1658 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1659         .rpc_call_prepare = ff_layout_read_prepare_v3,
1660         .rpc_call_done = ff_layout_read_call_done,
1661         .rpc_count_stats = ff_layout_read_count_stats,
1662         .rpc_release = ff_layout_read_release,
1663 };
1664
1665 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1666         .rpc_call_prepare = ff_layout_read_prepare_v4,
1667         .rpc_call_done = ff_layout_read_call_done,
1668         .rpc_count_stats = ff_layout_read_count_stats,
1669         .rpc_release = ff_layout_read_release,
1670 };
1671
1672 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1673         .rpc_call_prepare = ff_layout_write_prepare_v3,
1674         .rpc_call_done = ff_layout_write_call_done,
1675         .rpc_count_stats = ff_layout_write_count_stats,
1676         .rpc_release = ff_layout_write_release,
1677 };
1678
1679 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1680         .rpc_call_prepare = ff_layout_write_prepare_v4,
1681         .rpc_call_done = ff_layout_write_call_done,
1682         .rpc_count_stats = ff_layout_write_count_stats,
1683         .rpc_release = ff_layout_write_release,
1684 };
1685
1686 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1687         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1688         .rpc_call_done = ff_layout_commit_done,
1689         .rpc_count_stats = ff_layout_commit_count_stats,
1690         .rpc_release = ff_layout_commit_release,
1691 };
1692
1693 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1694         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1695         .rpc_call_done = ff_layout_commit_done,
1696         .rpc_count_stats = ff_layout_commit_count_stats,
1697         .rpc_release = ff_layout_commit_release,
1698 };
1699
1700 static enum pnfs_try_status
1701 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1702 {
1703         struct pnfs_layout_segment *lseg = hdr->lseg;
1704         struct nfs4_pnfs_ds *ds;
1705         struct rpc_clnt *ds_clnt;
1706         const struct cred *ds_cred;
1707         loff_t offset = hdr->args.offset;
1708         u32 idx = hdr->pgio_mirror_idx;
1709         int vers;
1710         struct nfs_fh *fh;
1711
1712         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1713                 __func__, hdr->inode->i_ino,
1714                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1715
1716         ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
1717         if (!ds)
1718                 goto out_failed;
1719
1720         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1721                                                    hdr->inode);
1722         if (IS_ERR(ds_clnt))
1723                 goto out_failed;
1724
1725         ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1726         if (!ds_cred)
1727                 goto out_failed;
1728
1729         vers = nfs4_ff_layout_ds_version(lseg, idx);
1730
1731         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1732                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1733
1734         hdr->pgio_done_cb = ff_layout_read_done_cb;
1735         refcount_inc(&ds->ds_clp->cl_count);
1736         hdr->ds_clp = ds->ds_clp;
1737         fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1738         if (fh)
1739                 hdr->args.fh = fh;
1740
1741         if (vers == 4 &&
1742                 !nfs4_ff_layout_select_ds_stateid(lseg, idx, &hdr->args.stateid))
1743                 goto out_failed;
1744
1745         /*
1746          * Note that if we ever decide to split across DSes,
1747          * then we may need to handle dense-like offsets.
1748          */
1749         hdr->args.offset = offset;
1750         hdr->mds_offset = offset;
1751
1752         /* Perform an asynchronous read to ds */
1753         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1754                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1755                                       &ff_layout_read_call_ops_v4,
1756                           0, RPC_TASK_SOFTCONN);
1757         put_cred(ds_cred);
1758         return PNFS_ATTEMPTED;
1759
1760 out_failed:
1761         if (ff_layout_avoid_mds_available_ds(lseg))
1762                 return PNFS_TRY_AGAIN;
1763         return PNFS_NOT_ATTEMPTED;
1764 }
1765
1766 /* Perform async writes. */
1767 static enum pnfs_try_status
1768 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1769 {
1770         struct pnfs_layout_segment *lseg = hdr->lseg;
1771         struct nfs4_pnfs_ds *ds;
1772         struct rpc_clnt *ds_clnt;
1773         const struct cred *ds_cred;
1774         loff_t offset = hdr->args.offset;
1775         int vers;
1776         struct nfs_fh *fh;
1777         int idx = hdr->pgio_mirror_idx;
1778
1779         ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1780         if (!ds)
1781                 goto out_failed;
1782
1783         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1784                                                    hdr->inode);
1785         if (IS_ERR(ds_clnt))
1786                 goto out_failed;
1787
1788         ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1789         if (!ds_cred)
1790                 goto out_failed;
1791
1792         vers = nfs4_ff_layout_ds_version(lseg, idx);
1793
1794         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1795                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1796                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1797                 vers);
1798
1799         hdr->pgio_done_cb = ff_layout_write_done_cb;
1800         refcount_inc(&ds->ds_clp->cl_count);
1801         hdr->ds_clp = ds->ds_clp;
1802         hdr->ds_commit_idx = idx;
1803         fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1804         if (fh)
1805                 hdr->args.fh = fh;
1806
1807         if (vers == 4 &&
1808                 !nfs4_ff_layout_select_ds_stateid(lseg, idx, &hdr->args.stateid))
1809                 goto out_failed;
1810
1811         /*
1812          * Note that if we ever decide to split across DSes,
1813          * then we may need to handle dense-like offsets.
1814          */
1815         hdr->args.offset = offset;
1816
1817         /* Perform an asynchronous write */
1818         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1819                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1820                                       &ff_layout_write_call_ops_v4,
1821                           sync, RPC_TASK_SOFTCONN);
1822         put_cred(ds_cred);
1823         return PNFS_ATTEMPTED;
1824
1825 out_failed:
1826         if (ff_layout_avoid_mds_available_ds(lseg))
1827                 return PNFS_TRY_AGAIN;
1828         return PNFS_NOT_ATTEMPTED;
1829 }
1830
1831 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1832 {
1833         return i;
1834 }
1835
1836 static struct nfs_fh *
1837 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1838 {
1839         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1840
1841         /* FIXME: Assume that there is only one NFS version available
1842          * for the DS.
1843          */
1844         return &flseg->mirror_array[i]->fh_versions[0];
1845 }
1846
1847 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1848 {
1849         struct pnfs_layout_segment *lseg = data->lseg;
1850         struct nfs4_pnfs_ds *ds;
1851         struct rpc_clnt *ds_clnt;
1852         const struct cred *ds_cred;
1853         u32 idx;
1854         int vers, ret;
1855         struct nfs_fh *fh;
1856
1857         if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1858             test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1859                 goto out_err;
1860
1861         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1862         ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1863         if (!ds)
1864                 goto out_err;
1865
1866         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1867                                                    data->inode);
1868         if (IS_ERR(ds_clnt))
1869                 goto out_err;
1870
1871         ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
1872         if (!ds_cred)
1873                 goto out_err;
1874
1875         vers = nfs4_ff_layout_ds_version(lseg, idx);
1876
1877         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1878                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1879                 vers);
1880         data->commit_done_cb = ff_layout_commit_done_cb;
1881         data->cred = ds_cred;
1882         refcount_inc(&ds->ds_clp->cl_count);
1883         data->ds_clp = ds->ds_clp;
1884         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1885         if (fh)
1886                 data->args.fh = fh;
1887
1888         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1889                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1890                                                &ff_layout_commit_call_ops_v4,
1891                                    how, RPC_TASK_SOFTCONN);
1892         put_cred(ds_cred);
1893         return ret;
1894 out_err:
1895         pnfs_generic_prepare_to_resend_writes(data);
1896         pnfs_generic_commit_release(data);
1897         return -EAGAIN;
1898 }
1899
1900 static int
1901 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1902                            int how, struct nfs_commit_info *cinfo)
1903 {
1904         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1905                                             ff_layout_initiate_commit);
1906 }
1907
1908 static struct pnfs_ds_commit_info *
1909 ff_layout_get_ds_info(struct inode *inode)
1910 {
1911         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1912
1913         if (layout == NULL)
1914                 return NULL;
1915
1916         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1917 }
1918
1919 static void
1920 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1921 {
1922         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1923                                                   id_node));
1924 }
1925
1926 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
1927                                   const struct nfs4_layoutreturn_args *args,
1928                                   const struct nfs4_flexfile_layoutreturn_args *ff_args)
1929 {
1930         __be32 *start;
1931
1932         start = xdr_reserve_space(xdr, 4);
1933         if (unlikely(!start))
1934                 return -E2BIG;
1935
1936         *start = cpu_to_be32(ff_args->num_errors);
1937         /* This assume we always return _ALL_ layouts */
1938         return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
1939 }
1940
1941 static void
1942 encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
1943 {
1944         WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
1945 }
1946
1947 static void
1948 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
1949                             const nfs4_stateid *stateid,
1950                             const struct nfs42_layoutstat_devinfo *devinfo)
1951 {
1952         __be32 *p;
1953
1954         p = xdr_reserve_space(xdr, 8 + 8);
1955         p = xdr_encode_hyper(p, devinfo->offset);
1956         p = xdr_encode_hyper(p, devinfo->length);
1957         encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
1958         p = xdr_reserve_space(xdr, 4*8);
1959         p = xdr_encode_hyper(p, devinfo->read_count);
1960         p = xdr_encode_hyper(p, devinfo->read_bytes);
1961         p = xdr_encode_hyper(p, devinfo->write_count);
1962         p = xdr_encode_hyper(p, devinfo->write_bytes);
1963         encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
1964 }
1965
1966 static void
1967 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
1968                             const nfs4_stateid *stateid,
1969                             const struct nfs42_layoutstat_devinfo *devinfo)
1970 {
1971         ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
1972         ff_layout_encode_ff_layoutupdate(xdr, devinfo,
1973                         devinfo->ld_private.data);
1974 }
1975
1976 /* report nothing for now */
1977 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
1978                 const struct nfs4_layoutreturn_args *args,
1979                 struct nfs4_flexfile_layoutreturn_args *ff_args)
1980 {
1981         __be32 *p;
1982         int i;
1983
1984         p = xdr_reserve_space(xdr, 4);
1985         *p = cpu_to_be32(ff_args->num_dev);
1986         for (i = 0; i < ff_args->num_dev; i++)
1987                 ff_layout_encode_ff_iostat(xdr,
1988                                 &args->layout->plh_stateid,
1989                                 &ff_args->devinfo[i]);
1990 }
1991
1992 static void
1993 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
1994                 unsigned int num_entries)
1995 {
1996         unsigned int i;
1997
1998         for (i = 0; i < num_entries; i++) {
1999                 if (!devinfo[i].ld_private.ops)
2000                         continue;
2001                 if (!devinfo[i].ld_private.ops->free)
2002                         continue;
2003                 devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2004         }
2005 }
2006
2007 static struct nfs4_deviceid_node *
2008 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2009                               struct pnfs_device *pdev, gfp_t gfp_flags)
2010 {
2011         struct nfs4_ff_layout_ds *dsaddr;
2012
2013         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2014         if (!dsaddr)
2015                 return NULL;
2016         return &dsaddr->id_node;
2017 }
2018
2019 static void
2020 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2021                 const void *voidargs,
2022                 const struct nfs4_xdr_opaque_data *ff_opaque)
2023 {
2024         const struct nfs4_layoutreturn_args *args = voidargs;
2025         struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2026         struct xdr_buf tmp_buf = {
2027                 .head = {
2028                         [0] = {
2029                                 .iov_base = page_address(ff_args->pages[0]),
2030                         },
2031                 },
2032                 .buflen = PAGE_SIZE,
2033         };
2034         struct xdr_stream tmp_xdr;
2035         __be32 *start;
2036
2037         dprintk("%s: Begin\n", __func__);
2038
2039         xdr_init_encode(&tmp_xdr, &tmp_buf, NULL);
2040
2041         ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2042         ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2043
2044         start = xdr_reserve_space(xdr, 4);
2045         *start = cpu_to_be32(tmp_buf.len);
2046         xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2047
2048         dprintk("%s: Return\n", __func__);
2049 }
2050
2051 static void
2052 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2053 {
2054         struct nfs4_flexfile_layoutreturn_args *ff_args;
2055
2056         if (!args->data)
2057                 return;
2058         ff_args = args->data;
2059         args->data = NULL;
2060
2061         ff_layout_free_ds_ioerr(&ff_args->errors);
2062         ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2063
2064         put_page(ff_args->pages[0]);
2065         kfree(ff_args);
2066 }
2067
2068 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2069         .encode = ff_layout_encode_layoutreturn,
2070         .free = ff_layout_free_layoutreturn,
2071 };
2072
2073 static int
2074 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2075 {
2076         struct nfs4_flexfile_layoutreturn_args *ff_args;
2077         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2078
2079         ff_args = kmalloc(sizeof(*ff_args), GFP_KERNEL);
2080         if (!ff_args)
2081                 goto out_nomem;
2082         ff_args->pages[0] = alloc_page(GFP_KERNEL);
2083         if (!ff_args->pages[0])
2084                 goto out_nomem_free;
2085
2086         INIT_LIST_HEAD(&ff_args->errors);
2087         ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2088                         &args->range, &ff_args->errors,
2089                         FF_LAYOUTRETURN_MAXERR);
2090
2091         spin_lock(&args->inode->i_lock);
2092         ff_args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2093                         &ff_args->devinfo[0], ARRAY_SIZE(ff_args->devinfo));
2094         spin_unlock(&args->inode->i_lock);
2095
2096         args->ld_private->ops = &layoutreturn_ops;
2097         args->ld_private->data = ff_args;
2098         return 0;
2099 out_nomem_free:
2100         kfree(ff_args);
2101 out_nomem:
2102         return -ENOMEM;
2103 }
2104
2105 static int
2106 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2107 {
2108         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2109
2110         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2111 }
2112
2113 static size_t
2114 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2115                           const int buflen)
2116 {
2117         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2118         const struct in6_addr *addr = &sin6->sin6_addr;
2119
2120         /*
2121          * RFC 4291, Section 2.2.2
2122          *
2123          * Shorthanded ANY address
2124          */
2125         if (ipv6_addr_any(addr))
2126                 return snprintf(buf, buflen, "::");
2127
2128         /*
2129          * RFC 4291, Section 2.2.2
2130          *
2131          * Shorthanded loopback address
2132          */
2133         if (ipv6_addr_loopback(addr))
2134                 return snprintf(buf, buflen, "::1");
2135
2136         /*
2137          * RFC 4291, Section 2.2.3
2138          *
2139          * Special presentation address format for mapped v4
2140          * addresses.
2141          */
2142         if (ipv6_addr_v4mapped(addr))
2143                 return snprintf(buf, buflen, "::ffff:%pI4",
2144                                         &addr->s6_addr32[3]);
2145
2146         /*
2147          * RFC 4291, Section 2.2.1
2148          */
2149         return snprintf(buf, buflen, "%pI6c", addr);
2150 }
2151
2152 /* Derived from rpc_sockaddr2uaddr */
2153 static void
2154 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2155 {
2156         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2157         char portbuf[RPCBIND_MAXUADDRPLEN];
2158         char addrbuf[RPCBIND_MAXUADDRLEN];
2159         char *netid;
2160         unsigned short port;
2161         int len, netid_len;
2162         __be32 *p;
2163
2164         switch (sap->sa_family) {
2165         case AF_INET:
2166                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2167                         return;
2168                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2169                 netid = "tcp";
2170                 netid_len = 3;
2171                 break;
2172         case AF_INET6:
2173                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2174                         return;
2175                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2176                 netid = "tcp6";
2177                 netid_len = 4;
2178                 break;
2179         default:
2180                 /* we only support tcp and tcp6 */
2181                 WARN_ON_ONCE(1);
2182                 return;
2183         }
2184
2185         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2186         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2187
2188         p = xdr_reserve_space(xdr, 4 + netid_len);
2189         xdr_encode_opaque(p, netid, netid_len);
2190
2191         p = xdr_reserve_space(xdr, 4 + len);
2192         xdr_encode_opaque(p, addrbuf, len);
2193 }
2194
2195 static void
2196 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2197                          ktime_t t)
2198 {
2199         struct timespec64 ts;
2200         __be32 *p;
2201
2202         p = xdr_reserve_space(xdr, 12);
2203         ts = ktime_to_timespec64(t);
2204         p = xdr_encode_hyper(p, ts.tv_sec);
2205         *p++ = cpu_to_be32(ts.tv_nsec);
2206 }
2207
2208 static void
2209 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2210                             struct nfs4_ff_io_stat *stat)
2211 {
2212         __be32 *p;
2213
2214         p = xdr_reserve_space(xdr, 5 * 8);
2215         p = xdr_encode_hyper(p, stat->ops_requested);
2216         p = xdr_encode_hyper(p, stat->bytes_requested);
2217         p = xdr_encode_hyper(p, stat->ops_completed);
2218         p = xdr_encode_hyper(p, stat->bytes_completed);
2219         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2220         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2221         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2222 }
2223
2224 static void
2225 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2226                               const struct nfs42_layoutstat_devinfo *devinfo,
2227                               struct nfs4_ff_layout_mirror *mirror)
2228 {
2229         struct nfs4_pnfs_ds_addr *da;
2230         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2231         struct nfs_fh *fh = &mirror->fh_versions[0];
2232         __be32 *p;
2233
2234         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2235         dprintk("%s: DS %s: encoding address %s\n",
2236                 __func__, ds->ds_remotestr, da->da_remotestr);
2237         /* netaddr4 */
2238         ff_layout_encode_netaddr(xdr, da);
2239         /* nfs_fh4 */
2240         p = xdr_reserve_space(xdr, 4 + fh->size);
2241         xdr_encode_opaque(p, fh->data, fh->size);
2242         /* ff_io_latency4 read */
2243         spin_lock(&mirror->lock);
2244         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2245         /* ff_io_latency4 write */
2246         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2247         spin_unlock(&mirror->lock);
2248         /* nfstime4 */
2249         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2250         /* bool */
2251         p = xdr_reserve_space(xdr, 4);
2252         *p = cpu_to_be32(false);
2253 }
2254
2255 static void
2256 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2257                              const struct nfs4_xdr_opaque_data *opaque)
2258 {
2259         struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2260                         struct nfs42_layoutstat_devinfo, ld_private);
2261         __be32 *start;
2262
2263         /* layoutupdate length */
2264         start = xdr_reserve_space(xdr, 4);
2265         ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2266
2267         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2268 }
2269
2270 static void
2271 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2272 {
2273         struct nfs4_ff_layout_mirror *mirror = opaque->data;
2274
2275         ff_layout_put_mirror(mirror);
2276 }
2277
2278 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2279         .encode = ff_layout_encode_layoutstats,
2280         .free   = ff_layout_free_layoutstats,
2281 };
2282
2283 static int
2284 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2285                                struct nfs42_layoutstat_devinfo *devinfo,
2286                                int dev_limit)
2287 {
2288         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2289         struct nfs4_ff_layout_mirror *mirror;
2290         struct nfs4_deviceid_node *dev;
2291         int i = 0;
2292
2293         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2294                 if (i >= dev_limit)
2295                         break;
2296                 if (IS_ERR_OR_NULL(mirror->mirror_ds))
2297                         continue;
2298                 if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags))
2299                         continue;
2300                 /* mirror refcount put in cleanup_layoutstats */
2301                 if (!refcount_inc_not_zero(&mirror->ref))
2302                         continue;
2303                 dev = &mirror->mirror_ds->id_node;
2304                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2305                 devinfo->offset = 0;
2306                 devinfo->length = NFS4_MAX_UINT64;
2307                 spin_lock(&mirror->lock);
2308                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2309                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2310                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2311                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2312                 spin_unlock(&mirror->lock);
2313                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2314                 devinfo->ld_private.ops = &layoutstat_ops;
2315                 devinfo->ld_private.data = mirror;
2316
2317                 devinfo++;
2318                 i++;
2319         }
2320         return i;
2321 }
2322
2323 static int
2324 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2325 {
2326         struct nfs4_flexfile_layout *ff_layout;
2327         const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2328
2329         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2330         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
2331         if (!args->devinfo)
2332                 return -ENOMEM;
2333
2334         spin_lock(&args->inode->i_lock);
2335         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2336         args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2337                         &args->devinfo[0], dev_count);
2338         spin_unlock(&args->inode->i_lock);
2339         if (!args->num_dev) {
2340                 kfree(args->devinfo);
2341                 args->devinfo = NULL;
2342                 return -ENOENT;
2343         }
2344
2345         return 0;
2346 }
2347
2348 static int
2349 ff_layout_set_layoutdriver(struct nfs_server *server,
2350                 const struct nfs_fh *dummy)
2351 {
2352 #if IS_ENABLED(CONFIG_NFS_V4_2)
2353         server->caps |= NFS_CAP_LAYOUTSTATS;
2354 #endif
2355         return 0;
2356 }
2357
2358 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2359         .id                     = LAYOUT_FLEX_FILES,
2360         .name                   = "LAYOUT_FLEX_FILES",
2361         .owner                  = THIS_MODULE,
2362         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
2363         .max_layoutget_response = 4096, /* 1 page or so... */
2364         .set_layoutdriver       = ff_layout_set_layoutdriver,
2365         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2366         .free_layout_hdr        = ff_layout_free_layout_hdr,
2367         .alloc_lseg             = ff_layout_alloc_lseg,
2368         .free_lseg              = ff_layout_free_lseg,
2369         .add_lseg               = ff_layout_add_lseg,
2370         .pg_read_ops            = &ff_layout_pg_read_ops,
2371         .pg_write_ops           = &ff_layout_pg_write_ops,
2372         .get_ds_info            = ff_layout_get_ds_info,
2373         .free_deviceid_node     = ff_layout_free_deviceid_node,
2374         .mark_request_commit    = pnfs_layout_mark_request_commit,
2375         .clear_request_commit   = pnfs_generic_clear_request_commit,
2376         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2377         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2378         .commit_pagelist        = ff_layout_commit_pagelist,
2379         .read_pagelist          = ff_layout_read_pagelist,
2380         .write_pagelist         = ff_layout_write_pagelist,
2381         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2382         .prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2383         .sync                   = pnfs_nfs_generic_sync,
2384         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2385 };
2386
2387 static int __init nfs4flexfilelayout_init(void)
2388 {
2389         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2390                __func__);
2391         return pnfs_register_layoutdriver(&flexfilelayout_type);
2392 }
2393
2394 static void __exit nfs4flexfilelayout_exit(void)
2395 {
2396         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2397                __func__);
2398         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2399 }
2400
2401 MODULE_ALIAS("nfs-layouttype4-4");
2402
2403 MODULE_LICENSE("GPL");
2404 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2405
2406 module_init(nfs4flexfilelayout_init);
2407 module_exit(nfs4flexfilelayout_exit);