fs/nfs/flexfilelayout/flexfilelayout.c

   1 /*
   2  * Module for pnfs flexfile layout driver.
   3  *
   4  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   5  *
   6  * Tao Peng <bergwolf@primarydata.com>
   7  */
   8
   9 #include <linux/nfs_fs.h>
  10 #include <linux/nfs_page.h>
  11 #include <linux/module.h>
  12
  13 #include <linux/sunrpc/metrics.h>
  14
  15 #include "flexfilelayout.h"
  16 #include "../nfs4session.h"
  17 #include "../nfs4idmap.h"
  18 #include "../internal.h"
  19 #include "../delegation.h"
  20 #include "../nfs4trace.h"
  21 #include "../iostat.h"
  22 #include "../nfs.h"
  23 #include "../nfs42.h"
  24
  25 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  26
  27 #define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  28
  29 static struct group_info        *ff_zero_group;
  30
  31 static struct pnfs_layout_hdr *
  32 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  33 {
  34         struct nfs4_flexfile_layout *ffl;
  35
  36         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  37         if (ffl) {
  38                 INIT_LIST_HEAD(&ffl->error_list);
  39                 INIT_LIST_HEAD(&ffl->mirrors);
  40                 return &ffl->generic_hdr;
  41         } else
  42                 return NULL;
  43 }
  44
  45 static void
  46 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  47 {
  48         struct nfs4_ff_layout_ds_err *err, *n;
  49
  50         list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  51                                  list) {
  52                 list_del(&err->list);
  53                 kfree(err);
  54         }
  55         kfree(FF_LAYOUT_FROM_HDR(lo));
  56 }
  57
  58 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  59 {
  60         __be32 *p;
  61
  62         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  63         if (unlikely(p == NULL))
  64                 return -ENOBUFS;
  65         stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  66         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  67         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  68                 p[0], p[1], p[2], p[3]);
  69         return 0;
  70 }
  71
  72 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  73 {
  74         __be32 *p;
  75
  76         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  77         if (unlikely(!p))
  78                 return -ENOBUFS;
  79         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  80         nfs4_print_deviceid(devid);
  81         return 0;
  82 }
  83
  84 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  85 {
  86         __be32 *p;
  87
  88         p = xdr_inline_decode(xdr, 4);
  89         if (unlikely(!p))
  90                 return -ENOBUFS;
  91         fh->size = be32_to_cpup(p++);
  92         if (fh->size > sizeof(struct nfs_fh)) {
  93                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
  94                        fh->size);
  95                 return -EOVERFLOW;
  96         }
  97         /* fh.data */
  98         p = xdr_inline_decode(xdr, fh->size);
  99         if (unlikely(!p))
 100                 return -ENOBUFS;
 101         memcpy(&fh->data, p, fh->size);
 102         dprintk("%s: fh len %d\n", __func__, fh->size);
 103
 104         return 0;
 105 }
 106
 107 /*
 108  * Currently only stringified uids and gids are accepted.
 109  * I.e., kerberos is not supported to the DSes, so no pricipals.
 110  *
 111  * That means that one common function will suffice, but when
 112  * principals are added, this should be split to accomodate
 113  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 114  */
 115 static int
 116 decode_name(struct xdr_stream *xdr, u32 *id)
 117 {
 118         __be32 *p;
 119         int len;
 120
 121         /* opaque_length(4)*/
 122         p = xdr_inline_decode(xdr, 4);
 123         if (unlikely(!p))
 124                 return -ENOBUFS;
 125         len = be32_to_cpup(p++);
 126         if (len < 0)
 127                 return -EINVAL;
 128
 129         dprintk("%s: len %u\n", __func__, len);
 130
 131         /* opaque body */
 132         p = xdr_inline_decode(xdr, len);
 133         if (unlikely(!p))
 134                 return -ENOBUFS;
 135
 136         if (!nfs_map_string_to_numeric((char *)p, len, id))
 137                 return -EINVAL;
 138
 139         return 0;
 140 }
 141
 142 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 143                 const struct nfs4_ff_layout_mirror *m2)
 144 {
 145         int i, j;
 146
 147         if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 148                 return false;
 149         for (i = 0; i < m1->fh_versions_cnt; i++) {
 150                 bool found_fh = false;
 151                 for (j = 0; j < m2->fh_versions_cnt; j++) {
 152                         if (nfs_compare_fh(&m1->fh_versions[i],
 153                                         &m2->fh_versions[j]) == 0) {
 154                                 found_fh = true;
 155                                 break;
 156                         }
 157                 }
 158                 if (!found_fh)
 159                         return false;
 160         }
 161         return true;
 162 }
 163
 164 static struct nfs4_ff_layout_mirror *
 165 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 166                 struct nfs4_ff_layout_mirror *mirror)
 167 {
 168         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 169         struct nfs4_ff_layout_mirror *pos;
 170         struct inode *inode = lo->plh_inode;
 171
 172         spin_lock(&inode->i_lock);
 173         list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 174                 if (mirror->mirror_ds != pos->mirror_ds)
 175                         continue;
 176                 if (!ff_mirror_match_fh(mirror, pos))
 177                         continue;
 178                 if (atomic_inc_not_zero(&pos->ref)) {
 179                         spin_unlock(&inode->i_lock);
 180                         return pos;
 181                 }
 182         }
 183         list_add(&mirror->mirrors, &ff_layout->mirrors);
 184         mirror->layout = lo;
 185         spin_unlock(&inode->i_lock);
 186         return mirror;
 187 }
 188
 189 static void
 190 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 191 {
 192         struct inode *inode;
 193         if (mirror->layout == NULL)
 194                 return;
 195         inode = mirror->layout->plh_inode;
 196         spin_lock(&inode->i_lock);
 197         list_del(&mirror->mirrors);
 198         spin_unlock(&inode->i_lock);
 199         mirror->layout = NULL;
 200 }
 201
 202 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 203 {
 204         struct nfs4_ff_layout_mirror *mirror;
 205
 206         mirror = kzalloc(sizeof(*mirror), gfp_flags);
 207         if (mirror != NULL) {
 208                 spin_lock_init(&mirror->lock);
 209                 atomic_set(&mirror->ref, 1);
 210                 INIT_LIST_HEAD(&mirror->mirrors);
 211         }
 212         return mirror;
 213 }
 214
 215 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 216 {
 217         struct rpc_cred *cred;
 218
 219         ff_layout_remove_mirror(mirror);
 220         kfree(mirror->fh_versions);
 221         cred = rcu_access_pointer(mirror->ro_cred);
 222         if (cred)
 223                 put_rpccred(cred);
 224         cred = rcu_access_pointer(mirror->rw_cred);
 225         if (cred)
 226                 put_rpccred(cred);
 227         nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 228         kfree(mirror);
 229 }
 230
 231 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 232 {
 233         if (mirror != NULL && atomic_dec_and_test(&mirror->ref))
 234                 ff_layout_free_mirror(mirror);
 235 }
 236
 237 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 238 {
 239         int i;
 240
 241         if (fls->mirror_array) {
 242                 for (i = 0; i < fls->mirror_array_cnt; i++) {
 243                         /* normally mirror_ds is freed in
 244                          * .free_deviceid_node but we still do it here
 245                          * for .alloc_lseg error path */
 246                         ff_layout_put_mirror(fls->mirror_array[i]);
 247                 }
 248                 kfree(fls->mirror_array);
 249                 fls->mirror_array = NULL;
 250         }
 251 }
 252
 253 static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 254 {
 255         int ret = 0;
 256
 257         dprintk("--> %s\n", __func__);
 258
 259         /* FIXME: remove this check when layout segment support is added */
 260         if (lgr->range.offset != 0 ||
 261             lgr->range.length != NFS4_MAX_UINT64) {
 262                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 263                         __func__);
 264                 ret = -EINVAL;
 265         }
 266
 267         dprintk("--> %s returns %d\n", __func__, ret);
 268         return ret;
 269 }
 270
 271 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 272 {
 273         if (fls) {
 274                 ff_layout_free_mirror_array(fls);
 275                 kfree(fls);
 276         }
 277 }
 278
 279 static bool
 280 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 281                 const struct pnfs_layout_range *l2)
 282 {
 283         u64 end1, end2;
 284
 285         if (l1->iomode != l2->iomode)
 286                 return l1->iomode != IOMODE_READ;
 287         end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 288         end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 289         if (end1 < l2->offset)
 290                 return false;
 291         if (end2 < l1->offset)
 292                 return true;
 293         return l2->offset <= l1->offset;
 294 }
 295
 296 static bool
 297 ff_lseg_merge(struct pnfs_layout_segment *new,
 298                 struct pnfs_layout_segment *old)
 299 {
 300         u64 new_end, old_end;
 301
 302         if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 303                 return false;
 304         if (new->pls_range.iomode != old->pls_range.iomode)
 305                 return false;
 306         old_end = pnfs_calc_offset_end(old->pls_range.offset,
 307                         old->pls_range.length);
 308         if (old_end < new->pls_range.offset)
 309                 return false;
 310         new_end = pnfs_calc_offset_end(new->pls_range.offset,
 311                         new->pls_range.length);
 312         if (new_end < old->pls_range.offset)
 313                 return false;
 314
 315         /* Mergeable: copy info from 'old' to 'new' */
 316         if (new_end < old_end)
 317                 new_end = old_end;
 318         if (new->pls_range.offset < old->pls_range.offset)
 319                 new->pls_range.offset = old->pls_range.offset;
 320         new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 321                         new_end);
 322         if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 323                 set_bit(NFS_LSEG_ROC, &new->pls_flags);
 324         return true;
 325 }
 326
 327 static void
 328 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 329                 struct pnfs_layout_segment *lseg,
 330                 struct list_head *free_me)
 331 {
 332         pnfs_generic_layout_insert_lseg(lo, lseg,
 333                         ff_lseg_range_is_after,
 334                         ff_lseg_merge,
 335                         free_me);
 336 }
 337
 338 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 339 {
 340         int i, j;
 341
 342         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 343                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 344                         if (fls->mirror_array[i]->efficiency <
 345                             fls->mirror_array[j]->efficiency)
 346                                 swap(fls->mirror_array[i],
 347                                      fls->mirror_array[j]);
 348         }
 349 }
 350
 351 static void ff_layout_mark_devices_valid(struct nfs4_ff_layout_segment *fls)
 352 {
 353         struct nfs4_deviceid_node *node;
 354         int i;
 355
 356         if (!(fls->flags & FF_FLAGS_NO_IO_THRU_MDS))
 357                 return;
 358         for (i = 0; i < fls->mirror_array_cnt; i++) {
 359                 node = &fls->mirror_array[i]->mirror_ds->id_node;
 360                 clear_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
 361         }
 362 }
 363
 364 static struct pnfs_layout_segment *
 365 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 366                      struct nfs4_layoutget_res *lgr,
 367                      gfp_t gfp_flags)
 368 {
 369         struct pnfs_layout_segment *ret;
 370         struct nfs4_ff_layout_segment *fls = NULL;
 371         struct xdr_stream stream;
 372         struct xdr_buf buf;
 373         struct page *scratch;
 374         u64 stripe_unit;
 375         u32 mirror_array_cnt;
 376         __be32 *p;
 377         int i, rc;
 378
 379         dprintk("--> %s\n", __func__);
 380         scratch = alloc_page(gfp_flags);
 381         if (!scratch)
 382                 return ERR_PTR(-ENOMEM);
 383
 384         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 385                               lgr->layoutp->len);
 386         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 387
 388         /* stripe unit and mirror_array_cnt */
 389         rc = -EIO;
 390         p = xdr_inline_decode(&stream, 8 + 4);
 391         if (!p)
 392                 goto out_err_free;
 393
 394         p = xdr_decode_hyper(p, &stripe_unit);
 395         mirror_array_cnt = be32_to_cpup(p++);
 396         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 397                 stripe_unit, mirror_array_cnt);
 398
 399         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 400             mirror_array_cnt == 0)
 401                 goto out_err_free;
 402
 403         rc = -ENOMEM;
 404         fls = kzalloc(sizeof(*fls), gfp_flags);
 405         if (!fls)
 406                 goto out_err_free;
 407
 408         fls->mirror_array_cnt = mirror_array_cnt;
 409         fls->stripe_unit = stripe_unit;
 410         fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 411                                     sizeof(fls->mirror_array[0]), gfp_flags);
 412         if (fls->mirror_array == NULL)
 413                 goto out_err_free;
 414
 415         for (i = 0; i < fls->mirror_array_cnt; i++) {
 416                 struct nfs4_ff_layout_mirror *mirror;
 417                 struct nfs4_deviceid devid;
 418                 struct nfs4_deviceid_node *idnode;
 419                 struct auth_cred acred = { .group_info = ff_zero_group };
 420                 struct rpc_cred __rcu *cred;
 421                 u32 ds_count, fh_count, id;
 422                 int j;
 423
 424                 rc = -EIO;
 425                 p = xdr_inline_decode(&stream, 4);
 426                 if (!p)
 427                         goto out_err_free;
 428                 ds_count = be32_to_cpup(p);
 429
 430                 /* FIXME: allow for striping? */
 431                 if (ds_count != 1)
 432                         goto out_err_free;
 433
 434                 fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 435                 if (fls->mirror_array[i] == NULL) {
 436                         rc = -ENOMEM;
 437                         goto out_err_free;
 438                 }
 439
 440                 fls->mirror_array[i]->ds_count = ds_count;
 441
 442                 /* deviceid */
 443                 rc = decode_deviceid(&stream, &devid);
 444                 if (rc)
 445                         goto out_err_free;
 446
 447                 idnode = nfs4_find_get_deviceid(NFS_SERVER(lh->plh_inode),
 448                                                 &devid, lh->plh_lc_cred,
 449                                                 gfp_flags);
 450                 /*
 451                  * upon success, mirror_ds is allocated by previous
 452                  * getdeviceinfo, or newly by .alloc_deviceid_node
 453                  * nfs4_find_get_deviceid failure is indeed getdeviceinfo falure
 454                  */
 455                 if (idnode)
 456                         fls->mirror_array[i]->mirror_ds =
 457                                 FF_LAYOUT_MIRROR_DS(idnode);
 458                 else
 459                         goto out_err_free;
 460
 461                 /* efficiency */
 462                 rc = -EIO;
 463                 p = xdr_inline_decode(&stream, 4);
 464                 if (!p)
 465                         goto out_err_free;
 466                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 467
 468                 /* stateid */
 469                 rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 470                 if (rc)
 471                         goto out_err_free;
 472
 473                 /* fh */
 474                 p = xdr_inline_decode(&stream, 4);
 475                 if (!p)
 476                         goto out_err_free;
 477                 fh_count = be32_to_cpup(p);
 478
 479                 fls->mirror_array[i]->fh_versions =
 480                         kzalloc(fh_count * sizeof(struct nfs_fh),
 481                                 gfp_flags);
 482                 if (fls->mirror_array[i]->fh_versions == NULL) {
 483                         rc = -ENOMEM;
 484                         goto out_err_free;
 485                 }
 486
 487                 for (j = 0; j < fh_count; j++) {
 488                         rc = decode_nfs_fh(&stream,
 489                                            &fls->mirror_array[i]->fh_versions[j]);
 490                         if (rc)
 491                                 goto out_err_free;
 492                 }
 493
 494                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 495
 496                 /* user */
 497                 rc = decode_name(&stream, &id);
 498                 if (rc)
 499                         goto out_err_free;
 500
 501                 acred.uid = make_kuid(&init_user_ns, id);
 502
 503                 /* group */
 504                 rc = decode_name(&stream, &id);
 505                 if (rc)
 506                         goto out_err_free;
 507
 508                 acred.gid = make_kgid(&init_user_ns, id);
 509
 510                 /* find the cred for it */
 511                 rcu_assign_pointer(cred, rpc_lookup_generic_cred(&acred, 0, gfp_flags));
 512                 if (IS_ERR(cred)) {
 513                         rc = PTR_ERR(cred);
 514                         goto out_err_free;
 515                 }
 516
 517                 if (lgr->range.iomode == IOMODE_READ)
 518                         rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 519                 else
 520                         rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 521
 522                 mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 523                 if (mirror != fls->mirror_array[i]) {
 524                         /* swap cred ptrs so free_mirror will clean up old */
 525                         if (lgr->range.iomode == IOMODE_READ) {
 526                                 cred = xchg(&mirror->ro_cred, cred);
 527                                 rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 528                         } else {
 529                                 cred = xchg(&mirror->rw_cred, cred);
 530                                 rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 531                         }
 532                         ff_layout_free_mirror(fls->mirror_array[i]);
 533                         fls->mirror_array[i] = mirror;
 534                 }
 535
 536                 dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 537                         lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 538                         from_kuid(&init_user_ns, acred.uid),
 539                         from_kgid(&init_user_ns, acred.gid));
 540         }
 541
 542         p = xdr_inline_decode(&stream, 4);
 543         if (!p)
 544                 goto out_sort_mirrors;
 545         fls->flags = be32_to_cpup(p);
 546
 547         p = xdr_inline_decode(&stream, 4);
 548         if (!p)
 549                 goto out_sort_mirrors;
 550         for (i=0; i < fls->mirror_array_cnt; i++)
 551                 fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 552
 553 out_sort_mirrors:
 554         ff_layout_sort_mirrors(fls);
 555         rc = ff_layout_check_layout(lgr);
 556         if (rc)
 557                 goto out_err_free;
 558         ff_layout_mark_devices_valid(fls);
 559
 560         ret = &fls->generic_hdr;
 561         dprintk("<-- %s (success)\n", __func__);
 562 out_free_page:
 563         __free_page(scratch);
 564         return ret;
 565 out_err_free:
 566         _ff_layout_free_lseg(fls);
 567         ret = ERR_PTR(rc);
 568         dprintk("<-- %s (%d)\n", __func__, rc);
 569         goto out_free_page;
 570 }
 571
 572 static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 573 {
 574         struct pnfs_layout_segment *lseg;
 575
 576         list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 577                 if (lseg->pls_range.iomode == IOMODE_RW)
 578                         return true;
 579
 580         return false;
 581 }
 582
 583 static void
 584 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 585 {
 586         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 587
 588         dprintk("--> %s\n", __func__);
 589
 590         if (lseg->pls_range.iomode == IOMODE_RW) {
 591                 struct nfs4_flexfile_layout *ffl;
 592                 struct inode *inode;
 593
 594                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 595                 inode = ffl->generic_hdr.plh_inode;
 596                 spin_lock(&inode->i_lock);
 597                 if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 598                         ffl->commit_info.nbuckets = 0;
 599                         kfree(ffl->commit_info.buckets);
 600                         ffl->commit_info.buckets = NULL;
 601                 }
 602                 spin_unlock(&inode->i_lock);
 603         }
 604         _ff_layout_free_lseg(fls);
 605 }
 606
 607 /* Return 1 until we have multiple lsegs support */
 608 static int
 609 ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 610 {
 611         return 1;
 612 }
 613
 614 static void
 615 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 616 {
 617         /* first IO request? */
 618         if (atomic_inc_return(&timer->n_ops) == 1) {
 619                 timer->start_time = now;
 620         }
 621 }
 622
 623 static ktime_t
 624 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 625 {
 626         ktime_t start;
 627
 628         if (atomic_dec_return(&timer->n_ops) < 0)
 629                 WARN_ON_ONCE(1);
 630
 631         start = timer->start_time;
 632         timer->start_time = now;
 633         return ktime_sub(now, start);
 634 }
 635
 636 static bool
 637 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 638                             struct nfs4_ff_layoutstat *layoutstat,
 639                             ktime_t now)
 640 {
 641         static const ktime_t notime = {0};
 642         s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 643
 644         nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 645         if (ktime_equal(mirror->start_time, notime))
 646                 mirror->start_time = now;
 647         if (ktime_equal(mirror->last_report_time, notime))
 648                 mirror->last_report_time = now;
 649         if (mirror->report_interval != 0)
 650                 report_interval = (s64)mirror->report_interval * 1000LL;
 651         else if (layoutstats_timer != 0)
 652                 report_interval = (s64)layoutstats_timer * 1000LL;
 653         if (ktime_to_ms(ktime_sub(now, mirror->last_report_time)) >=
 654                         report_interval) {
 655                 mirror->last_report_time = now;
 656                 return true;
 657         }
 658
 659         return false;
 660 }
 661
 662 static void
 663 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 664                 __u64 requested)
 665 {
 666         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 667
 668         iostat->ops_requested++;
 669         iostat->bytes_requested += requested;
 670 }
 671
 672 static void
 673 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 674                 __u64 requested,
 675                 __u64 completed,
 676                 ktime_t time_completed,
 677                 ktime_t time_started)
 678 {
 679         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 680         ktime_t completion_time = ktime_sub(time_completed, time_started);
 681         ktime_t timer;
 682
 683         iostat->ops_completed++;
 684         iostat->bytes_completed += completed;
 685         iostat->bytes_not_delivered += requested - completed;
 686
 687         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 688         iostat->total_busy_time =
 689                         ktime_add(iostat->total_busy_time, timer);
 690         iostat->aggregate_completion_time =
 691                         ktime_add(iostat->aggregate_completion_time,
 692                                         completion_time);
 693 }
 694
 695 static void
 696 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 697                 struct nfs4_ff_layout_mirror *mirror,
 698                 __u64 requested, ktime_t now)
 699 {
 700         bool report;
 701
 702         spin_lock(&mirror->lock);
 703         report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 704         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 705         spin_unlock(&mirror->lock);
 706
 707         if (report)
 708                 pnfs_report_layoutstat(inode, GFP_KERNEL);
 709 }
 710
 711 static void
 712 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 713                 struct nfs4_ff_layout_mirror *mirror,
 714                 __u64 requested,
 715                 __u64 completed)
 716 {
 717         spin_lock(&mirror->lock);
 718         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 719                         requested, completed,
 720                         ktime_get(), task->tk_start);
 721         spin_unlock(&mirror->lock);
 722 }
 723
 724 static void
 725 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 726                 struct nfs4_ff_layout_mirror *mirror,
 727                 __u64 requested, ktime_t now)
 728 {
 729         bool report;
 730
 731         spin_lock(&mirror->lock);
 732         report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 733         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 734         spin_unlock(&mirror->lock);
 735
 736         if (report)
 737                 pnfs_report_layoutstat(inode, GFP_NOIO);
 738 }
 739
 740 static void
 741 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 742                 struct nfs4_ff_layout_mirror *mirror,
 743                 __u64 requested,
 744                 __u64 completed,
 745                 enum nfs3_stable_how committed)
 746 {
 747         if (committed == NFS_UNSTABLE)
 748                 requested = completed = 0;
 749
 750         spin_lock(&mirror->lock);
 751         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 752                         requested, completed, ktime_get(), task->tk_start);
 753         spin_unlock(&mirror->lock);
 754 }
 755
 756 static int
 757 ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 758                             struct nfs_commit_info *cinfo,
 759                             gfp_t gfp_flags)
 760 {
 761         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 762         struct pnfs_commit_bucket *buckets;
 763         int size;
 764
 765         if (cinfo->ds->nbuckets != 0) {
 766                 /* This assumes there is only one RW lseg per file.
 767                  * To support multiple lseg per file, we need to
 768                  * change struct pnfs_commit_bucket to allow dynamic
 769                  * increasing nbuckets.
 770                  */
 771                 return 0;
 772         }
 773
 774         size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 775
 776         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 777                           gfp_flags);
 778         if (!buckets)
 779                 return -ENOMEM;
 780         else {
 781                 int i;
 782
 783                 spin_lock(&cinfo->inode->i_lock);
 784                 if (cinfo->ds->nbuckets != 0)
 785                         kfree(buckets);
 786                 else {
 787                         cinfo->ds->buckets = buckets;
 788                         cinfo->ds->nbuckets = size;
 789                         for (i = 0; i < size; i++) {
 790                                 INIT_LIST_HEAD(&buckets[i].written);
 791                                 INIT_LIST_HEAD(&buckets[i].committing);
 792                                 /* mark direct verifier as unset */
 793                                 buckets[i].direct_verf.committed =
 794                                         NFS_INVALID_STABLE_HOW;
 795                         }
 796                 }
 797                 spin_unlock(&cinfo->inode->i_lock);
 798                 return 0;
 799         }
 800 }
 801
 802 static struct nfs4_pnfs_ds *
 803 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 804                                   int start_idx,
 805                                   int *best_idx)
 806 {
 807         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 808         struct nfs4_pnfs_ds *ds;
 809         int idx;
 810
 811         /* mirrors are sorted by efficiency */
 812         for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 813                 ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
 814                 if (ds) {
 815                         *best_idx = idx;
 816                         return ds;
 817                 }
 818         }
 819
 820         return NULL;
 821 }
 822
 823 static void
 824 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 825                       struct nfs_page *req,
 826                       bool strict_iomode)
 827 {
 828 retry_strict:
 829         pnfs_put_lseg(pgio->pg_lseg);
 830         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 831                                            req->wb_context,
 832                                            0,
 833                                            NFS4_MAX_UINT64,
 834                                            IOMODE_READ,
 835                                            strict_iomode,
 836                                            GFP_KERNEL);
 837         if (IS_ERR(pgio->pg_lseg)) {
 838                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 839                 pgio->pg_lseg = NULL;
 840         }
 841
 842         /* If we don't have checking, do get a IOMODE_RW
 843          * segment, and the server wants to avoid READs
 844          * there, then retry!
 845          */
 846         if (pgio->pg_lseg && !strict_iomode &&
 847             ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 848                 strict_iomode = true;
 849                 goto retry_strict;
 850         }
 851 }
 852
 853 static void
 854 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 855                         struct nfs_page *req)
 856 {
 857         struct nfs_pgio_mirror *pgm;
 858         struct nfs4_ff_layout_mirror *mirror;
 859         struct nfs4_pnfs_ds *ds;
 860         int ds_idx;
 861
 862         /* Use full layout for now */
 863         if (!pgio->pg_lseg)
 864                 ff_layout_pg_get_read(pgio, req, false);
 865         else if (ff_layout_avoid_read_on_rw(pgio->pg_lseg))
 866                 ff_layout_pg_get_read(pgio, req, true);
 867
 868         /* If no lseg, fall back to read through mds */
 869         if (pgio->pg_lseg == NULL)
 870                 goto out_mds;
 871
 872         ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 873         if (!ds) {
 874                 if (ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 875                         goto out_pnfs;
 876                 else
 877                         goto out_mds;
 878         }
 879
 880         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 881
 882         pgio->pg_mirror_idx = ds_idx;
 883
 884         /* read always uses only one mirror - idx 0 for pgio layer */
 885         pgm = &pgio->pg_mirrors[0];
 886         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 887
 888         return;
 889 out_mds:
 890         pnfs_put_lseg(pgio->pg_lseg);
 891         pgio->pg_lseg = NULL;
 892         nfs_pageio_reset_read_mds(pgio);
 893         return;
 894
 895 out_pnfs:
 896         pnfs_set_lo_fail(pgio->pg_lseg);
 897         pnfs_put_lseg(pgio->pg_lseg);
 898         pgio->pg_lseg = NULL;
 899 }
 900
 901 static void
 902 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 903                         struct nfs_page *req)
 904 {
 905         struct nfs4_ff_layout_mirror *mirror;
 906         struct nfs_pgio_mirror *pgm;
 907         struct nfs_commit_info cinfo;
 908         struct nfs4_pnfs_ds *ds;
 909         int i;
 910         int status;
 911
 912         if (!pgio->pg_lseg) {
 913                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 914                                                    req->wb_context,
 915                                                    0,
 916                                                    NFS4_MAX_UINT64,
 917                                                    IOMODE_RW,
 918                                                    false,
 919                                                    GFP_NOFS);
 920                 if (IS_ERR(pgio->pg_lseg)) {
 921                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 922                         pgio->pg_lseg = NULL;
 923                         return;
 924                 }
 925         }
 926         /* If no lseg, fall back to write through mds */
 927         if (pgio->pg_lseg == NULL)
 928                 goto out_mds;
 929
 930         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 931         status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 932         if (status < 0)
 933                 goto out_mds;
 934
 935         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 936         if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 937             FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 938                 goto out_mds;
 939
 940         for (i = 0; i < pgio->pg_mirror_count; i++) {
 941                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
 942                 if (!ds) {
 943                         if (ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 944                                 goto out_pnfs;
 945                         else
 946                                 goto out_mds;
 947                 }
 948                 pgm = &pgio->pg_mirrors[i];
 949                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 950                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 951         }
 952
 953         return;
 954
 955 out_mds:
 956         pnfs_put_lseg(pgio->pg_lseg);
 957         pgio->pg_lseg = NULL;
 958         nfs_pageio_reset_write_mds(pgio);
 959         return;
 960
 961 out_pnfs:
 962         pnfs_set_lo_fail(pgio->pg_lseg);
 963         pnfs_put_lseg(pgio->pg_lseg);
 964         pgio->pg_lseg = NULL;
 965 }
 966
 967 static unsigned int
 968 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 969                                     struct nfs_page *req)
 970 {
 971         if (!pgio->pg_lseg) {
 972                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 973                                                    req->wb_context,
 974                                                    0,
 975                                                    NFS4_MAX_UINT64,
 976                                                    IOMODE_RW,
 977                                                    false,
 978                                                    GFP_NOFS);
 979                 if (IS_ERR(pgio->pg_lseg)) {
 980                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 981                         pgio->pg_lseg = NULL;
 982                         goto out;
 983                 }
 984         }
 985         if (pgio->pg_lseg)
 986                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 987
 988         /* no lseg means that pnfs is not in use, so no mirroring here */
 989         nfs_pageio_reset_write_mds(pgio);
 990 out:
 991         return 1;
 992 }
 993
 994 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 995         .pg_init = ff_layout_pg_init_read,
 996         .pg_test = pnfs_generic_pg_test,
 997         .pg_doio = pnfs_generic_pg_readpages,
 998         .pg_cleanup = pnfs_generic_pg_cleanup,
 999 };
1000
1001 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
1002         .pg_init = ff_layout_pg_init_write,
1003         .pg_test = pnfs_generic_pg_test,
1004         .pg_doio = pnfs_generic_pg_writepages,
1005         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1006         .pg_cleanup = pnfs_generic_pg_cleanup,
1007 };
1008
1009 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1010 {
1011         struct rpc_task *task = &hdr->task;
1012
1013         pnfs_layoutcommit_inode(hdr->inode, false);
1014
1015         if (retry_pnfs) {
1016                 dprintk("%s Reset task %5u for i/o through pNFS "
1017                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1018                         hdr->task.tk_pid,
1019                         hdr->inode->i_sb->s_id,
1020                         (unsigned long long)NFS_FILEID(hdr->inode),
1021                         hdr->args.count,
1022                         (unsigned long long)hdr->args.offset);
1023
1024                 hdr->completion_ops->reschedule_io(hdr);
1025                 return;
1026         }
1027
1028         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1029                 dprintk("%s Reset task %5u for i/o through MDS "
1030                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1031                         hdr->task.tk_pid,
1032                         hdr->inode->i_sb->s_id,
1033                         (unsigned long long)NFS_FILEID(hdr->inode),
1034                         hdr->args.count,
1035                         (unsigned long long)hdr->args.offset);
1036
1037                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1038         }
1039 }
1040
1041 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1042 {
1043         struct rpc_task *task = &hdr->task;
1044
1045         pnfs_layoutcommit_inode(hdr->inode, false);
1046
1047         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1048                 dprintk("%s Reset task %5u for i/o through MDS "
1049                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1050                         hdr->task.tk_pid,
1051                         hdr->inode->i_sb->s_id,
1052                         (unsigned long long)NFS_FILEID(hdr->inode),
1053                         hdr->args.count,
1054                         (unsigned long long)hdr->args.offset);
1055
1056                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1057         }
1058 }
1059
1060 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1061                                            struct nfs4_state *state,
1062                                            struct nfs_client *clp,
1063                                            struct pnfs_layout_segment *lseg,
1064                                            int idx)
1065 {
1066         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1067         struct inode *inode = lo->plh_inode;
1068         struct nfs_server *mds_server = NFS_SERVER(inode);
1069
1070         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1071         struct nfs_client *mds_client = mds_server->nfs_client;
1072         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1073
1074         if (task->tk_status >= 0)
1075                 return 0;
1076
1077         switch (task->tk_status) {
1078         /* MDS state errors */
1079         case -NFS4ERR_DELEG_REVOKED:
1080         case -NFS4ERR_ADMIN_REVOKED:
1081         case -NFS4ERR_BAD_STATEID:
1082                 if (state == NULL)
1083                         break;
1084                 nfs_remove_bad_delegation(state->inode);
1085         case -NFS4ERR_OPENMODE:
1086                 if (state == NULL)
1087                         break;
1088                 if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
1089                         goto out_bad_stateid;
1090                 goto wait_on_recovery;
1091         case -NFS4ERR_EXPIRED:
1092                 if (state != NULL) {
1093                         if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
1094                                 goto out_bad_stateid;
1095                 }
1096                 nfs4_schedule_lease_recovery(mds_client);
1097                 goto wait_on_recovery;
1098         /* DS session errors */
1099         case -NFS4ERR_BADSESSION:
1100         case -NFS4ERR_BADSLOT:
1101         case -NFS4ERR_BAD_HIGH_SLOT:
1102         case -NFS4ERR_DEADSESSION:
1103         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1104         case -NFS4ERR_SEQ_FALSE_RETRY:
1105         case -NFS4ERR_SEQ_MISORDERED:
1106                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1107                         "flags 0x%x\n", __func__, task->tk_status,
1108                         clp->cl_exchange_flags);
1109                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1110                 break;
1111         case -NFS4ERR_DELAY:
1112         case -NFS4ERR_GRACE:
1113                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1114                 break;
1115         case -NFS4ERR_RETRY_UNCACHED_REP:
1116                 break;
1117         /* Invalidate Layout errors */
1118         case -NFS4ERR_PNFS_NO_LAYOUT:
1119         case -ESTALE:           /* mapped NFS4ERR_STALE */
1120         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1121         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1122         case -NFS4ERR_FHEXPIRED:
1123         case -NFS4ERR_WRONG_TYPE:
1124                 dprintk("%s Invalid layout error %d\n", __func__,
1125                         task->tk_status);
1126                 /*
1127                  * Destroy layout so new i/o will get a new layout.
1128                  * Layout will not be destroyed until all current lseg
1129                  * references are put. Mark layout as invalid to resend failed
1130                  * i/o and all i/o waiting on the slot table to the MDS until
1131                  * layout is destroyed and a new valid layout is obtained.
1132                  */
1133                 pnfs_destroy_layout(NFS_I(inode));
1134                 rpc_wake_up(&tbl->slot_tbl_waitq);
1135                 goto reset;
1136         /* RPC connection errors */
1137         case -ECONNREFUSED:
1138         case -EHOSTDOWN:
1139         case -EHOSTUNREACH:
1140         case -ENETUNREACH:
1141         case -EIO:
1142         case -ETIMEDOUT:
1143         case -EPIPE:
1144                 dprintk("%s DS connection error %d\n", __func__,
1145                         task->tk_status);
1146                 nfs4_mark_deviceid_unavailable(devid);
1147                 rpc_wake_up(&tbl->slot_tbl_waitq);
1148                 /* fall through */
1149         default:
1150                 if (ff_layout_avoid_mds_available_ds(lseg))
1151                         return -NFS4ERR_RESET_TO_PNFS;
1152 reset:
1153                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1154                         task->tk_status);
1155                 return -NFS4ERR_RESET_TO_MDS;
1156         }
1157 out:
1158         task->tk_status = 0;
1159         return -EAGAIN;
1160 out_bad_stateid:
1161         task->tk_status = -EIO;
1162         return 0;
1163 wait_on_recovery:
1164         rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
1165         if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
1166                 rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
1167         goto out;
1168 }
1169
1170 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1171 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1172                                            struct pnfs_layout_segment *lseg,
1173                                            int idx)
1174 {
1175         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1176
1177         if (task->tk_status >= 0)
1178                 return 0;
1179
1180         switch (task->tk_status) {
1181         /* File access problems. Don't mark the device as unavailable */
1182         case -EACCES:
1183         case -ESTALE:
1184         case -EISDIR:
1185         case -EBADHANDLE:
1186         case -ELOOP:
1187         case -ENOSPC:
1188                 break;
1189         case -EJUKEBOX:
1190                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1191                 goto out_retry;
1192         default:
1193                 dprintk("%s DS connection error %d\n", __func__,
1194                         task->tk_status);
1195                 nfs4_mark_deviceid_unavailable(devid);
1196         }
1197         /* FIXME: Need to prevent infinite looping here. */
1198         return -NFS4ERR_RESET_TO_PNFS;
1199 out_retry:
1200         task->tk_status = 0;
1201         rpc_restart_call_prepare(task);
1202         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1203         return -EAGAIN;
1204 }
1205
1206 static int ff_layout_async_handle_error(struct rpc_task *task,
1207                                         struct nfs4_state *state,
1208                                         struct nfs_client *clp,
1209                                         struct pnfs_layout_segment *lseg,
1210                                         int idx)
1211 {
1212         int vers = clp->cl_nfs_mod->rpc_vers->number;
1213
1214         switch (vers) {
1215         case 3:
1216                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1217         case 4:
1218                 return ff_layout_async_handle_error_v4(task, state, clp,
1219                                                        lseg, idx);
1220         default:
1221                 /* should never happen */
1222                 WARN_ON_ONCE(1);
1223                 return 0;
1224         }
1225 }
1226
1227 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1228                                         int idx, u64 offset, u64 length,
1229                                         u32 status, int opnum, int error)
1230 {
1231         struct nfs4_ff_layout_mirror *mirror;
1232         int err;
1233
1234         if (status == 0) {
1235                 switch (error) {
1236                 case -ETIMEDOUT:
1237                 case -EPFNOSUPPORT:
1238                 case -EPROTONOSUPPORT:
1239                 case -EOPNOTSUPP:
1240                 case -ECONNREFUSED:
1241                 case -ECONNRESET:
1242                 case -EHOSTDOWN:
1243                 case -EHOSTUNREACH:
1244                 case -ENETUNREACH:
1245                 case -EADDRINUSE:
1246                 case -ENOBUFS:
1247                 case -EPIPE:
1248                 case -EPERM:
1249                         status = NFS4ERR_NXIO;
1250                         break;
1251                 case -EACCES:
1252                         status = NFS4ERR_ACCESS;
1253                         break;
1254                 default:
1255                         return;
1256                 }
1257         }
1258
1259         switch (status) {
1260         case NFS4ERR_DELAY:
1261         case NFS4ERR_GRACE:
1262                 return;
1263         default:
1264                 break;
1265         }
1266
1267         mirror = FF_LAYOUT_COMP(lseg, idx);
1268         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1269                                        mirror, offset, length, status, opnum,
1270                                        GFP_NOIO);
1271         pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
1272         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1273 }
1274
1275 /* NFS_PROTO call done callback routines */
1276 static int ff_layout_read_done_cb(struct rpc_task *task,
1277                                 struct nfs_pgio_header *hdr)
1278 {
1279         int err;
1280
1281         trace_nfs4_pnfs_read(hdr, task->tk_status);
1282         if (task->tk_status < 0)
1283                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1284                                             hdr->args.offset, hdr->args.count,
1285                                             hdr->res.op_status, OP_READ,
1286                                             task->tk_status);
1287         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1288                                            hdr->ds_clp, hdr->lseg,
1289                                            hdr->pgio_mirror_idx);
1290
1291         switch (err) {
1292         case -NFS4ERR_RESET_TO_PNFS:
1293                 if (ff_layout_choose_best_ds_for_read(hdr->lseg,
1294                                         hdr->pgio_mirror_idx + 1,
1295                                         &hdr->pgio_mirror_idx))
1296                         goto out_eagain;
1297                 pnfs_read_resend_pnfs(hdr);
1298                 return task->tk_status;
1299         case -NFS4ERR_RESET_TO_MDS:
1300                 ff_layout_reset_read(hdr);
1301                 return task->tk_status;
1302         case -EAGAIN:
1303                 goto out_eagain;
1304         }
1305
1306         return 0;
1307 out_eagain:
1308         rpc_restart_call_prepare(task);
1309         return -EAGAIN;
1310 }
1311
1312 static bool
1313 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1314 {
1315         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1316 }
1317
1318 /*
1319  * We reference the rpc_cred of the first WRITE that triggers the need for
1320  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1321  * rfc5661 is not clear about which credential should be used.
1322  *
1323  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1324  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1325  * we always send layoutcommit after DS writes.
1326  */
1327 static void
1328 ff_layout_set_layoutcommit(struct inode *inode,
1329                 struct pnfs_layout_segment *lseg,
1330                 loff_t end_offset)
1331 {
1332         if (!ff_layout_need_layoutcommit(lseg))
1333                 return;
1334
1335         pnfs_set_layoutcommit(inode, lseg, end_offset);
1336         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1337                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1338 }
1339
1340 static bool
1341 ff_layout_device_unavailable(struct pnfs_layout_segment *lseg, int idx)
1342 {
1343         /* No mirroring for now */
1344         struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
1345
1346         return ff_layout_test_devid_unavailable(node);
1347 }
1348
1349 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1350                 struct nfs_pgio_header *hdr)
1351 {
1352         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1353                 return;
1354         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1355                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1356                         hdr->args.count,
1357                         task->tk_start);
1358 }
1359
1360 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1361                 struct nfs_pgio_header *hdr)
1362 {
1363         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1364                 return;
1365         nfs4_ff_layout_stat_io_end_read(task,
1366                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1367                         hdr->args.count,
1368                         hdr->res.count);
1369 }
1370
1371 static int ff_layout_read_prepare_common(struct rpc_task *task,
1372                                          struct nfs_pgio_header *hdr)
1373 {
1374         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1375                 rpc_exit(task, -EIO);
1376                 return -EIO;
1377         }
1378         if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1379                 rpc_exit(task, -EHOSTDOWN);
1380                 return -EAGAIN;
1381         }
1382
1383         ff_layout_read_record_layoutstats_start(task, hdr);
1384         return 0;
1385 }
1386
1387 /*
1388  * Call ops for the async read/write cases
1389  * In the case of dense layouts, the offset needs to be reset to its
1390  * original value.
1391  */
1392 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1393 {
1394         struct nfs_pgio_header *hdr = data;
1395
1396         if (ff_layout_read_prepare_common(task, hdr))
1397                 return;
1398
1399         rpc_call_start(task);
1400 }
1401
1402 static int ff_layout_setup_sequence(struct nfs_client *ds_clp,
1403                                     struct nfs4_sequence_args *args,
1404                                     struct nfs4_sequence_res *res,
1405                                     struct rpc_task *task)
1406 {
1407         if (ds_clp->cl_session)
1408                 return nfs41_setup_sequence(ds_clp->cl_session,
1409                                            args,
1410                                            res,
1411                                            task);
1412         return nfs40_setup_sequence(ds_clp->cl_slot_tbl,
1413                                    args,
1414                                    res,
1415                                    task);
1416 }
1417
1418 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1419 {
1420         struct nfs_pgio_header *hdr = data;
1421
1422         if (ff_layout_setup_sequence(hdr->ds_clp,
1423                                      &hdr->args.seq_args,
1424                                      &hdr->res.seq_res,
1425                                      task))
1426                 return;
1427
1428         if (ff_layout_read_prepare_common(task, hdr))
1429                 return;
1430
1431         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1432                         hdr->args.lock_context, FMODE_READ) == -EIO)
1433                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1434 }
1435
1436 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1437 {
1438         struct nfs_pgio_header *hdr = data;
1439
1440         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1441
1442         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1443             task->tk_status == 0) {
1444                 nfs4_sequence_done(task, &hdr->res.seq_res);
1445                 return;
1446         }
1447
1448         /* Note this may cause RPC to be resent */
1449         hdr->mds_ops->rpc_call_done(task, hdr);
1450 }
1451
1452 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1453 {
1454         struct nfs_pgio_header *hdr = data;
1455
1456         ff_layout_read_record_layoutstats_done(task, hdr);
1457         rpc_count_iostats_metrics(task,
1458             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1459 }
1460
1461 static void ff_layout_read_release(void *data)
1462 {
1463         struct nfs_pgio_header *hdr = data;
1464
1465         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1466         pnfs_generic_rw_release(data);
1467 }
1468
1469
1470 static int ff_layout_write_done_cb(struct rpc_task *task,
1471                                 struct nfs_pgio_header *hdr)
1472 {
1473         loff_t end_offs = 0;
1474         int err;
1475
1476         trace_nfs4_pnfs_write(hdr, task->tk_status);
1477         if (task->tk_status < 0)
1478                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1479                                             hdr->args.offset, hdr->args.count,
1480                                             hdr->res.op_status, OP_WRITE,
1481                                             task->tk_status);
1482         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1483                                            hdr->ds_clp, hdr->lseg,
1484                                            hdr->pgio_mirror_idx);
1485
1486         switch (err) {
1487         case -NFS4ERR_RESET_TO_PNFS:
1488                 ff_layout_reset_write(hdr, true);
1489                 return task->tk_status;
1490         case -NFS4ERR_RESET_TO_MDS:
1491                 ff_layout_reset_write(hdr, false);
1492                 return task->tk_status;
1493         case -EAGAIN:
1494                 return -EAGAIN;
1495         }
1496
1497         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1498             hdr->res.verf->committed == NFS_DATA_SYNC)
1499                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1500
1501         /* Note: if the write is unstable, don't set end_offs until commit */
1502         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1503
1504         /* zero out fattr since we don't care DS attr at all */
1505         hdr->fattr.valid = 0;
1506         if (task->tk_status >= 0)
1507                 nfs_writeback_update_inode(hdr);
1508
1509         return 0;
1510 }
1511
1512 static int ff_layout_commit_done_cb(struct rpc_task *task,
1513                                      struct nfs_commit_data *data)
1514 {
1515         int err;
1516
1517         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1518         if (task->tk_status < 0)
1519                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1520                                             data->args.offset, data->args.count,
1521                                             data->res.op_status, OP_COMMIT,
1522                                             task->tk_status);
1523         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1524                                            data->lseg, data->ds_commit_index);
1525
1526         switch (err) {
1527         case -NFS4ERR_RESET_TO_PNFS:
1528                 pnfs_generic_prepare_to_resend_writes(data);
1529                 return -EAGAIN;
1530         case -NFS4ERR_RESET_TO_MDS:
1531                 pnfs_generic_prepare_to_resend_writes(data);
1532                 return -EAGAIN;
1533         case -EAGAIN:
1534                 rpc_restart_call_prepare(task);
1535                 return -EAGAIN;
1536         }
1537
1538         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1539
1540         return 0;
1541 }
1542
1543 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1544                 struct nfs_pgio_header *hdr)
1545 {
1546         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1547                 return;
1548         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1549                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1550                         hdr->args.count,
1551                         task->tk_start);
1552 }
1553
1554 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1555                 struct nfs_pgio_header *hdr)
1556 {
1557         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1558                 return;
1559         nfs4_ff_layout_stat_io_end_write(task,
1560                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1561                         hdr->args.count, hdr->res.count,
1562                         hdr->res.verf->committed);
1563 }
1564
1565 static int ff_layout_write_prepare_common(struct rpc_task *task,
1566                                           struct nfs_pgio_header *hdr)
1567 {
1568         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1569                 rpc_exit(task, -EIO);
1570                 return -EIO;
1571         }
1572
1573         if (ff_layout_device_unavailable(hdr->lseg, hdr->pgio_mirror_idx)) {
1574                 rpc_exit(task, -EHOSTDOWN);
1575                 return -EAGAIN;
1576         }
1577
1578         ff_layout_write_record_layoutstats_start(task, hdr);
1579         return 0;
1580 }
1581
1582 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1583 {
1584         struct nfs_pgio_header *hdr = data;
1585
1586         if (ff_layout_write_prepare_common(task, hdr))
1587                 return;
1588
1589         rpc_call_start(task);
1590 }
1591
1592 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1593 {
1594         struct nfs_pgio_header *hdr = data;
1595
1596         if (ff_layout_setup_sequence(hdr->ds_clp,
1597                                      &hdr->args.seq_args,
1598                                      &hdr->res.seq_res,
1599                                      task))
1600                 return;
1601
1602         if (ff_layout_write_prepare_common(task, hdr))
1603                 return;
1604
1605         if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
1606                         hdr->args.lock_context, FMODE_WRITE) == -EIO)
1607                 rpc_exit(task, -EIO); /* lost lock, terminate I/O */
1608 }
1609
1610 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1611 {
1612         struct nfs_pgio_header *hdr = data;
1613
1614         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1615             task->tk_status == 0) {
1616                 nfs4_sequence_done(task, &hdr->res.seq_res);
1617                 return;
1618         }
1619
1620         /* Note this may cause RPC to be resent */
1621         hdr->mds_ops->rpc_call_done(task, hdr);
1622 }
1623
1624 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1625 {
1626         struct nfs_pgio_header *hdr = data;
1627
1628         ff_layout_write_record_layoutstats_done(task, hdr);
1629         rpc_count_iostats_metrics(task,
1630             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1631 }
1632
1633 static void ff_layout_write_release(void *data)
1634 {
1635         struct nfs_pgio_header *hdr = data;
1636
1637         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1638         pnfs_generic_rw_release(data);
1639 }
1640
1641 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1642                 struct nfs_commit_data *cdata)
1643 {
1644         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1645                 return;
1646         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1647                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1648                         0, task->tk_start);
1649 }
1650
1651 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1652                 struct nfs_commit_data *cdata)
1653 {
1654         struct nfs_page *req;
1655         __u64 count = 0;
1656
1657         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1658                 return;
1659
1660         if (task->tk_status == 0) {
1661                 list_for_each_entry(req, &cdata->pages, wb_list)
1662                         count += req->wb_bytes;
1663         }
1664         nfs4_ff_layout_stat_io_end_write(task,
1665                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1666                         count, count, NFS_FILE_SYNC);
1667 }
1668
1669 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1670                 struct nfs_commit_data *cdata)
1671 {
1672         ff_layout_commit_record_layoutstats_start(task, cdata);
1673 }
1674
1675 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1676 {
1677         ff_layout_commit_prepare_common(task, data);
1678         rpc_call_start(task);
1679 }
1680
1681 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1682 {
1683         struct nfs_commit_data *wdata = data;
1684
1685         if (ff_layout_setup_sequence(wdata->ds_clp,
1686                                  &wdata->args.seq_args,
1687                                  &wdata->res.seq_res,
1688                                  task))
1689                 return;
1690         ff_layout_commit_prepare_common(task, data);
1691 }
1692
1693 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1694 {
1695         pnfs_generic_write_commit_done(task, data);
1696 }
1697
1698 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1699 {
1700         struct nfs_commit_data *cdata = data;
1701
1702         ff_layout_commit_record_layoutstats_done(task, cdata);
1703         rpc_count_iostats_metrics(task,
1704             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1705 }
1706
1707 static void ff_layout_commit_release(void *data)
1708 {
1709         struct nfs_commit_data *cdata = data;
1710
1711         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1712         pnfs_generic_commit_release(data);
1713 }
1714
1715 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1716         .rpc_call_prepare = ff_layout_read_prepare_v3,
1717         .rpc_call_done = ff_layout_read_call_done,
1718         .rpc_count_stats = ff_layout_read_count_stats,
1719         .rpc_release = ff_layout_read_release,
1720 };
1721
1722 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1723         .rpc_call_prepare = ff_layout_read_prepare_v4,
1724         .rpc_call_done = ff_layout_read_call_done,
1725         .rpc_count_stats = ff_layout_read_count_stats,
1726         .rpc_release = ff_layout_read_release,
1727 };
1728
1729 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1730         .rpc_call_prepare = ff_layout_write_prepare_v3,
1731         .rpc_call_done = ff_layout_write_call_done,
1732         .rpc_count_stats = ff_layout_write_count_stats,
1733         .rpc_release = ff_layout_write_release,
1734 };
1735
1736 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1737         .rpc_call_prepare = ff_layout_write_prepare_v4,
1738         .rpc_call_done = ff_layout_write_call_done,
1739         .rpc_count_stats = ff_layout_write_count_stats,
1740         .rpc_release = ff_layout_write_release,
1741 };
1742
1743 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1744         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1745         .rpc_call_done = ff_layout_commit_done,
1746         .rpc_count_stats = ff_layout_commit_count_stats,
1747         .rpc_release = ff_layout_commit_release,
1748 };
1749
1750 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1751         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1752         .rpc_call_done = ff_layout_commit_done,
1753         .rpc_count_stats = ff_layout_commit_count_stats,
1754         .rpc_release = ff_layout_commit_release,
1755 };
1756
1757 static enum pnfs_try_status
1758 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1759 {
1760         struct pnfs_layout_segment *lseg = hdr->lseg;
1761         struct nfs4_pnfs_ds *ds;
1762         struct rpc_clnt *ds_clnt;
1763         struct rpc_cred *ds_cred;
1764         loff_t offset = hdr->args.offset;
1765         u32 idx = hdr->pgio_mirror_idx;
1766         int vers;
1767         struct nfs_fh *fh;
1768
1769         dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
1770                 __func__, hdr->inode->i_ino,
1771                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1772
1773         ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
1774         if (!ds)
1775                 goto out_failed;
1776
1777         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1778                                                    hdr->inode);
1779         if (IS_ERR(ds_clnt))
1780                 goto out_failed;
1781
1782         ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1783         if (!ds_cred)
1784                 goto out_failed;
1785
1786         vers = nfs4_ff_layout_ds_version(lseg, idx);
1787
1788         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1789                 ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count), vers);
1790
1791         hdr->pgio_done_cb = ff_layout_read_done_cb;
1792         atomic_inc(&ds->ds_clp->cl_count);
1793         hdr->ds_clp = ds->ds_clp;
1794         fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1795         if (fh)
1796                 hdr->args.fh = fh;
1797         /*
1798          * Note that if we ever decide to split across DSes,
1799          * then we may need to handle dense-like offsets.
1800          */
1801         hdr->args.offset = offset;
1802         hdr->mds_offset = offset;
1803
1804         /* Perform an asynchronous read to ds */
1805         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1806                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1807                                       &ff_layout_read_call_ops_v4,
1808                           0, RPC_TASK_SOFTCONN);
1809         put_rpccred(ds_cred);
1810         return PNFS_ATTEMPTED;
1811
1812 out_failed:
1813         if (ff_layout_avoid_mds_available_ds(lseg))
1814                 return PNFS_TRY_AGAIN;
1815         return PNFS_NOT_ATTEMPTED;
1816 }
1817
1818 /* Perform async writes. */
1819 static enum pnfs_try_status
1820 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1821 {
1822         struct pnfs_layout_segment *lseg = hdr->lseg;
1823         struct nfs4_pnfs_ds *ds;
1824         struct rpc_clnt *ds_clnt;
1825         struct rpc_cred *ds_cred;
1826         loff_t offset = hdr->args.offset;
1827         int vers;
1828         struct nfs_fh *fh;
1829         int idx = hdr->pgio_mirror_idx;
1830
1831         ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1832         if (!ds)
1833                 return PNFS_NOT_ATTEMPTED;
1834
1835         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1836                                                    hdr->inode);
1837         if (IS_ERR(ds_clnt))
1838                 return PNFS_NOT_ATTEMPTED;
1839
1840         ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
1841         if (!ds_cred)
1842                 return PNFS_NOT_ATTEMPTED;
1843
1844         vers = nfs4_ff_layout_ds_version(lseg, idx);
1845
1846         dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d vers %d\n",
1847                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1848                 offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count),
1849                 vers);
1850
1851         hdr->pgio_done_cb = ff_layout_write_done_cb;
1852         atomic_inc(&ds->ds_clp->cl_count);
1853         hdr->ds_clp = ds->ds_clp;
1854         hdr->ds_commit_idx = idx;
1855         fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
1856         if (fh)
1857                 hdr->args.fh = fh;
1858
1859         /*
1860          * Note that if we ever decide to split across DSes,
1861          * then we may need to handle dense-like offsets.
1862          */
1863         hdr->args.offset = offset;
1864
1865         /* Perform an asynchronous write */
1866         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1867                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1868                                       &ff_layout_write_call_ops_v4,
1869                           sync, RPC_TASK_SOFTCONN);
1870         put_rpccred(ds_cred);
1871         return PNFS_ATTEMPTED;
1872 }
1873
1874 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1875 {
1876         return i;
1877 }
1878
1879 static struct nfs_fh *
1880 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1881 {
1882         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1883
1884         /* FIXME: Assume that there is only one NFS version available
1885          * for the DS.
1886          */
1887         return &flseg->mirror_array[i]->fh_versions[0];
1888 }
1889
1890 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1891 {
1892         struct pnfs_layout_segment *lseg = data->lseg;
1893         struct nfs4_pnfs_ds *ds;
1894         struct rpc_clnt *ds_clnt;
1895         struct rpc_cred *ds_cred;
1896         u32 idx;
1897         int vers, ret;
1898         struct nfs_fh *fh;
1899
1900         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1901         ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
1902         if (!ds)
1903                 goto out_err;
1904
1905         ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
1906                                                    data->inode);
1907         if (IS_ERR(ds_clnt))
1908                 goto out_err;
1909
1910         ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
1911         if (!ds_cred)
1912                 goto out_err;
1913
1914         vers = nfs4_ff_layout_ds_version(lseg, idx);
1915
1916         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1917                 data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count),
1918                 vers);
1919         data->commit_done_cb = ff_layout_commit_done_cb;
1920         data->cred = ds_cred;
1921         atomic_inc(&ds->ds_clp->cl_count);
1922         data->ds_clp = ds->ds_clp;
1923         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1924         if (fh)
1925                 data->args.fh = fh;
1926
1927         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1928                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1929                                                &ff_layout_commit_call_ops_v4,
1930                                    how, RPC_TASK_SOFTCONN);
1931         put_rpccred(ds_cred);
1932         return ret;
1933 out_err:
1934         pnfs_generic_prepare_to_resend_writes(data);
1935         pnfs_generic_commit_release(data);
1936         return -EAGAIN;
1937 }
1938
1939 static int
1940 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1941                            int how, struct nfs_commit_info *cinfo)
1942 {
1943         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1944                                             ff_layout_initiate_commit);
1945 }
1946
1947 static struct pnfs_ds_commit_info *
1948 ff_layout_get_ds_info(struct inode *inode)
1949 {
1950         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1951
1952         if (layout == NULL)
1953                 return NULL;
1954
1955         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1956 }
1957
1958 static void
1959 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1960 {
1961         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1962                                                   id_node));
1963 }
1964
1965 static int ff_layout_encode_ioerr(struct nfs4_flexfile_layout *flo,
1966                                   struct xdr_stream *xdr,
1967                                   const struct nfs4_layoutreturn_args *args)
1968 {
1969         struct pnfs_layout_hdr *hdr = &flo->generic_hdr;
1970         __be32 *start;
1971         int count = 0, ret = 0;
1972
1973         start = xdr_reserve_space(xdr, 4);
1974         if (unlikely(!start))
1975                 return -E2BIG;
1976
1977         /* This assume we always return _ALL_ layouts */
1978         spin_lock(&hdr->plh_inode->i_lock);
1979         ret = ff_layout_encode_ds_ioerr(flo, xdr, &count, &args->range);
1980         spin_unlock(&hdr->plh_inode->i_lock);
1981
1982         *start = cpu_to_be32(count);
1983
1984         return ret;
1985 }
1986
1987 /* report nothing for now */
1988 static void ff_layout_encode_iostats(struct nfs4_flexfile_layout *flo,
1989                                      struct xdr_stream *xdr,
1990                                      const struct nfs4_layoutreturn_args *args)
1991 {
1992         __be32 *p;
1993
1994         p = xdr_reserve_space(xdr, 4);
1995         if (likely(p))
1996                 *p = cpu_to_be32(0);
1997 }
1998
1999 static struct nfs4_deviceid_node *
2000 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2001                               struct pnfs_device *pdev, gfp_t gfp_flags)
2002 {
2003         struct nfs4_ff_layout_ds *dsaddr;
2004
2005         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2006         if (!dsaddr)
2007                 return NULL;
2008         return &dsaddr->id_node;
2009 }
2010
2011 static void
2012 ff_layout_encode_layoutreturn(struct pnfs_layout_hdr *lo,
2013                               struct xdr_stream *xdr,
2014                               const struct nfs4_layoutreturn_args *args)
2015 {
2016         struct nfs4_flexfile_layout *flo = FF_LAYOUT_FROM_HDR(lo);
2017         __be32 *start;
2018
2019         dprintk("%s: Begin\n", __func__);
2020         start = xdr_reserve_space(xdr, 4);
2021         BUG_ON(!start);
2022
2023         ff_layout_encode_ioerr(flo, xdr, args);
2024         ff_layout_encode_iostats(flo, xdr, args);
2025
2026         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2027         dprintk("%s: Return\n", __func__);
2028 }
2029
2030 static int
2031 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2032 {
2033         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2034
2035         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2036 }
2037
2038 static size_t
2039 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2040                           const int buflen)
2041 {
2042         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2043         const struct in6_addr *addr = &sin6->sin6_addr;
2044
2045         /*
2046          * RFC 4291, Section 2.2.2
2047          *
2048          * Shorthanded ANY address
2049          */
2050         if (ipv6_addr_any(addr))
2051                 return snprintf(buf, buflen, "::");
2052
2053         /*
2054          * RFC 4291, Section 2.2.2
2055          *
2056          * Shorthanded loopback address
2057          */
2058         if (ipv6_addr_loopback(addr))
2059                 return snprintf(buf, buflen, "::1");
2060
2061         /*
2062          * RFC 4291, Section 2.2.3
2063          *
2064          * Special presentation address format for mapped v4
2065          * addresses.
2066          */
2067         if (ipv6_addr_v4mapped(addr))
2068                 return snprintf(buf, buflen, "::ffff:%pI4",
2069                                         &addr->s6_addr32[3]);
2070
2071         /*
2072          * RFC 4291, Section 2.2.1
2073          */
2074         return snprintf(buf, buflen, "%pI6c", addr);
2075 }
2076
2077 /* Derived from rpc_sockaddr2uaddr */
2078 static void
2079 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2080 {
2081         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2082         char portbuf[RPCBIND_MAXUADDRPLEN];
2083         char addrbuf[RPCBIND_MAXUADDRLEN];
2084         char *netid;
2085         unsigned short port;
2086         int len, netid_len;
2087         __be32 *p;
2088
2089         switch (sap->sa_family) {
2090         case AF_INET:
2091                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2092                         return;
2093                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2094                 netid = "tcp";
2095                 netid_len = 3;
2096                 break;
2097         case AF_INET6:
2098                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2099                         return;
2100                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2101                 netid = "tcp6";
2102                 netid_len = 4;
2103                 break;
2104         default:
2105                 /* we only support tcp and tcp6 */
2106                 WARN_ON_ONCE(1);
2107                 return;
2108         }
2109
2110         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2111         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2112
2113         p = xdr_reserve_space(xdr, 4 + netid_len);
2114         xdr_encode_opaque(p, netid, netid_len);
2115
2116         p = xdr_reserve_space(xdr, 4 + len);
2117         xdr_encode_opaque(p, addrbuf, len);
2118 }
2119
2120 static void
2121 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2122                          ktime_t t)
2123 {
2124         struct timespec64 ts;
2125         __be32 *p;
2126
2127         p = xdr_reserve_space(xdr, 12);
2128         ts = ktime_to_timespec64(t);
2129         p = xdr_encode_hyper(p, ts.tv_sec);
2130         *p++ = cpu_to_be32(ts.tv_nsec);
2131 }
2132
2133 static void
2134 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2135                             struct nfs4_ff_io_stat *stat)
2136 {
2137         __be32 *p;
2138
2139         p = xdr_reserve_space(xdr, 5 * 8);
2140         p = xdr_encode_hyper(p, stat->ops_requested);
2141         p = xdr_encode_hyper(p, stat->bytes_requested);
2142         p = xdr_encode_hyper(p, stat->ops_completed);
2143         p = xdr_encode_hyper(p, stat->bytes_completed);
2144         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2145         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2146         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2147 }
2148
2149 static void
2150 ff_layout_encode_layoutstats(struct xdr_stream *xdr,
2151                              struct nfs42_layoutstat_args *args,
2152                              struct nfs42_layoutstat_devinfo *devinfo)
2153 {
2154         struct nfs4_ff_layout_mirror *mirror = devinfo->layout_private;
2155         struct nfs4_pnfs_ds_addr *da;
2156         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2157         struct nfs_fh *fh = &mirror->fh_versions[0];
2158         __be32 *p, *start;
2159
2160         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2161         dprintk("%s: DS %s: encoding address %s\n",
2162                 __func__, ds->ds_remotestr, da->da_remotestr);
2163         /* layoutupdate length */
2164         start = xdr_reserve_space(xdr, 4);
2165         /* netaddr4 */
2166         ff_layout_encode_netaddr(xdr, da);
2167         /* nfs_fh4 */
2168         p = xdr_reserve_space(xdr, 4 + fh->size);
2169         xdr_encode_opaque(p, fh->data, fh->size);
2170         /* ff_io_latency4 read */
2171         spin_lock(&mirror->lock);
2172         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2173         /* ff_io_latency4 write */
2174         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2175         spin_unlock(&mirror->lock);
2176         /* nfstime4 */
2177         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2178         /* bool */
2179         p = xdr_reserve_space(xdr, 4);
2180         *p = cpu_to_be32(false);
2181
2182         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2183 }
2184
2185 static int
2186 ff_layout_mirror_prepare_stats(struct nfs42_layoutstat_args *args,
2187                                struct pnfs_layout_hdr *lo,
2188                                int dev_limit)
2189 {
2190         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2191         struct nfs4_ff_layout_mirror *mirror;
2192         struct nfs4_deviceid_node *dev;
2193         struct nfs42_layoutstat_devinfo *devinfo;
2194         int i = 0;
2195
2196         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2197                 if (i >= dev_limit)
2198                         break;
2199                 if (!mirror->mirror_ds)
2200                         continue;
2201                 /* mirror refcount put in cleanup_layoutstats */
2202                 if (!atomic_inc_not_zero(&mirror->ref))
2203                         continue;
2204                 dev = &mirror->mirror_ds->id_node;
2205                 devinfo = &args->devinfo[i];
2206                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2207                 devinfo->offset = 0;
2208                 devinfo->length = NFS4_MAX_UINT64;
2209                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2210                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2211                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2212                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2213                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2214                 devinfo->layoutstats_encode = ff_layout_encode_layoutstats;
2215                 devinfo->layout_private = mirror;
2216
2217                 i++;
2218         }
2219         return i;
2220 }
2221
2222 static int
2223 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2224 {
2225         struct nfs4_flexfile_layout *ff_layout;
2226         struct nfs4_ff_layout_mirror *mirror;
2227         int dev_count = 0;
2228
2229         spin_lock(&args->inode->i_lock);
2230         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2231         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2232                 if (atomic_read(&mirror->ref) != 0)
2233                         dev_count ++;
2234         }
2235         spin_unlock(&args->inode->i_lock);
2236         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2237         if (dev_count > PNFS_LAYOUTSTATS_MAXDEV) {
2238                 dprintk("%s: truncating devinfo to limit (%d:%d)\n",
2239                         __func__, dev_count, PNFS_LAYOUTSTATS_MAXDEV);
2240                 dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2241         }
2242         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
2243         if (!args->devinfo)
2244                 return -ENOMEM;
2245
2246         spin_lock(&args->inode->i_lock);
2247         args->num_dev = ff_layout_mirror_prepare_stats(args,
2248                         &ff_layout->generic_hdr, dev_count);
2249         spin_unlock(&args->inode->i_lock);
2250
2251         return 0;
2252 }
2253
2254 static void
2255 ff_layout_cleanup_layoutstats(struct nfs42_layoutstat_data *data)
2256 {
2257         struct nfs4_ff_layout_mirror *mirror;
2258         int i;
2259
2260         for (i = 0; i < data->args.num_dev; i++) {
2261                 mirror = data->args.devinfo[i].layout_private;
2262                 data->args.devinfo[i].layout_private = NULL;
2263                 ff_layout_put_mirror(mirror);
2264         }
2265 }
2266
2267 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2268         .id                     = LAYOUT_FLEX_FILES,
2269         .name                   = "LAYOUT_FLEX_FILES",
2270         .owner                  = THIS_MODULE,
2271         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2272         .free_layout_hdr        = ff_layout_free_layout_hdr,
2273         .alloc_lseg             = ff_layout_alloc_lseg,
2274         .free_lseg              = ff_layout_free_lseg,
2275         .add_lseg               = ff_layout_add_lseg,
2276         .pg_read_ops            = &ff_layout_pg_read_ops,
2277         .pg_write_ops           = &ff_layout_pg_write_ops,
2278         .get_ds_info            = ff_layout_get_ds_info,
2279         .free_deviceid_node     = ff_layout_free_deviceid_node,
2280         .mark_request_commit    = pnfs_layout_mark_request_commit,
2281         .clear_request_commit   = pnfs_generic_clear_request_commit,
2282         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2283         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2284         .commit_pagelist        = ff_layout_commit_pagelist,
2285         .read_pagelist          = ff_layout_read_pagelist,
2286         .write_pagelist         = ff_layout_write_pagelist,
2287         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2288         .encode_layoutreturn    = ff_layout_encode_layoutreturn,
2289         .sync                   = pnfs_nfs_generic_sync,
2290         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2291         .cleanup_layoutstats    = ff_layout_cleanup_layoutstats,
2292 };
2293
2294 static int __init nfs4flexfilelayout_init(void)
2295 {
2296         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2297                __func__);
2298         if (!ff_zero_group) {
2299                 ff_zero_group = groups_alloc(0);
2300                 if (!ff_zero_group)
2301                         return -ENOMEM;
2302         }
2303         return pnfs_register_layoutdriver(&flexfilelayout_type);
2304 }
2305
2306 static void __exit nfs4flexfilelayout_exit(void)
2307 {
2308         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2309                __func__);
2310         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2311         if (ff_zero_group) {
2312                 put_group_info(ff_zero_group);
2313                 ff_zero_group = NULL;
2314         }
2315 }
2316
2317 MODULE_ALIAS("nfs-layouttype4-4");
2318
2319 MODULE_LICENSE("GPL");
2320 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2321
2322 module_init(nfs4flexfilelayout_init);
2323 module_exit(nfs4flexfilelayout_exit);