fs/nfs/flexfilelayout/flexfilelayout.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Module for pnfs flexfile layout driver.
   4  *
   5  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   6  *
   7  * Tao Peng <[email protected]>
   8  */
   9
  10 #include <linux/nfs_fs.h>
  11 #include <linux/nfs_mount.h>
  12 #include <linux/nfs_page.h>
  13 #include <linux/module.h>
  14 #include <linux/sched/mm.h>
  15
  16 #include <linux/sunrpc/metrics.h>
  17
  18 #include "flexfilelayout.h"
  19 #include "../nfs4session.h"
  20 #include "../nfs4idmap.h"
  21 #include "../internal.h"
  22 #include "../delegation.h"
  23 #include "../nfs4trace.h"
  24 #include "../iostat.h"
  25 #include "../nfs.h"
  26 #include "../nfs42.h"
  27
  28 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  29
  30 #define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  31 #define FF_LAYOUTRETURN_MAXERR 20
  32
  33 enum nfs4_ff_op_type {
  34         NFS4_FF_OP_LAYOUTSTATS,
  35         NFS4_FF_OP_LAYOUTRETURN,
  36 };
  37
  38 static unsigned short io_maxretrans;
  39
  40 static const struct pnfs_commit_ops ff_layout_commit_ops;
  41 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
  42                 struct nfs_pgio_header *hdr);
  43 static int
  44 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
  45                                struct nfs42_layoutstat_devinfo *devinfo,
  46                                int dev_limit, enum nfs4_ff_op_type type);
  47 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
  48                               const struct nfs42_layoutstat_devinfo *devinfo,
  49                               struct nfs4_ff_layout_mirror *mirror);
  50
  51 static struct pnfs_layout_hdr *
  52 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  53 {
  54         struct nfs4_flexfile_layout *ffl;
  55
  56         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  57         if (ffl) {
  58                 pnfs_init_ds_commit_info(&ffl->commit_info);
  59                 INIT_LIST_HEAD(&ffl->error_list);
  60                 INIT_LIST_HEAD(&ffl->mirrors);
  61                 ffl->last_report_time = ktime_get();
  62                 ffl->commit_info.ops = &ff_layout_commit_ops;
  63                 return &ffl->generic_hdr;
  64         } else
  65                 return NULL;
  66 }
  67
  68 static void
  69 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  70 {
  71         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(lo);
  72         struct nfs4_ff_layout_ds_err *err, *n;
  73
  74         list_for_each_entry_safe(err, n, &ffl->error_list, list) {
  75                 list_del(&err->list);
  76                 kfree(err);
  77         }
  78         kfree_rcu(ffl, generic_hdr.plh_rcu);
  79 }
  80
  81 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  82 {
  83         __be32 *p;
  84
  85         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  86         if (unlikely(p == NULL))
  87                 return -ENOBUFS;
  88         stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  89         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  90         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  91                 p[0], p[1], p[2], p[3]);
  92         return 0;
  93 }
  94
  95 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  96 {
  97         __be32 *p;
  98
  99         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
 100         if (unlikely(!p))
 101                 return -ENOBUFS;
 102         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
 103         nfs4_print_deviceid(devid);
 104         return 0;
 105 }
 106
 107 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 108 {
 109         __be32 *p;
 110
 111         p = xdr_inline_decode(xdr, 4);
 112         if (unlikely(!p))
 113                 return -ENOBUFS;
 114         fh->size = be32_to_cpup(p++);
 115         if (fh->size > NFS_MAXFHSIZE) {
 116                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
 117                        fh->size);
 118                 return -EOVERFLOW;
 119         }
 120         /* fh.data */
 121         p = xdr_inline_decode(xdr, fh->size);
 122         if (unlikely(!p))
 123                 return -ENOBUFS;
 124         memcpy(&fh->data, p, fh->size);
 125         dprintk("%s: fh len %d\n", __func__, fh->size);
 126
 127         return 0;
 128 }
 129
 130 /*
 131  * Currently only stringified uids and gids are accepted.
 132  * I.e., kerberos is not supported to the DSes, so no pricipals.
 133  *
 134  * That means that one common function will suffice, but when
 135  * principals are added, this should be split to accomodate
 136  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 137  */
 138 static int
 139 decode_name(struct xdr_stream *xdr, u32 *id)
 140 {
 141         __be32 *p;
 142         int len;
 143
 144         /* opaque_length(4)*/
 145         p = xdr_inline_decode(xdr, 4);
 146         if (unlikely(!p))
 147                 return -ENOBUFS;
 148         len = be32_to_cpup(p++);
 149         if (len < 0)
 150                 return -EINVAL;
 151
 152         dprintk("%s: len %u\n", __func__, len);
 153
 154         /* opaque body */
 155         p = xdr_inline_decode(xdr, len);
 156         if (unlikely(!p))
 157                 return -ENOBUFS;
 158
 159         if (!nfs_map_string_to_numeric((char *)p, len, id))
 160                 return -EINVAL;
 161
 162         return 0;
 163 }
 164
 165 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 166                 const struct nfs4_ff_layout_mirror *m2)
 167 {
 168         int i, j;
 169
 170         if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 171                 return false;
 172         for (i = 0; i < m1->fh_versions_cnt; i++) {
 173                 bool found_fh = false;
 174                 for (j = 0; j < m2->fh_versions_cnt; j++) {
 175                         if (nfs_compare_fh(&m1->fh_versions[i],
 176                                         &m2->fh_versions[j]) == 0) {
 177                                 found_fh = true;
 178                                 break;
 179                         }
 180                 }
 181                 if (!found_fh)
 182                         return false;
 183         }
 184         return true;
 185 }
 186
 187 static struct nfs4_ff_layout_mirror *
 188 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 189                 struct nfs4_ff_layout_mirror *mirror)
 190 {
 191         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 192         struct nfs4_ff_layout_mirror *pos;
 193         struct inode *inode = lo->plh_inode;
 194
 195         spin_lock(&inode->i_lock);
 196         list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 197                 if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
 198                         continue;
 199                 if (!ff_mirror_match_fh(mirror, pos))
 200                         continue;
 201                 if (refcount_inc_not_zero(&pos->ref)) {
 202                         spin_unlock(&inode->i_lock);
 203                         return pos;
 204                 }
 205         }
 206         list_add(&mirror->mirrors, &ff_layout->mirrors);
 207         mirror->layout = lo;
 208         spin_unlock(&inode->i_lock);
 209         return mirror;
 210 }
 211
 212 static void
 213 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 214 {
 215         struct inode *inode;
 216         if (mirror->layout == NULL)
 217                 return;
 218         inode = mirror->layout->plh_inode;
 219         spin_lock(&inode->i_lock);
 220         list_del(&mirror->mirrors);
 221         spin_unlock(&inode->i_lock);
 222         mirror->layout = NULL;
 223 }
 224
 225 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 226 {
 227         struct nfs4_ff_layout_mirror *mirror;
 228
 229         mirror = kzalloc(sizeof(*mirror), gfp_flags);
 230         if (mirror != NULL) {
 231                 spin_lock_init(&mirror->lock);
 232                 refcount_set(&mirror->ref, 1);
 233                 INIT_LIST_HEAD(&mirror->mirrors);
 234         }
 235         return mirror;
 236 }
 237
 238 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 239 {
 240         const struct cred       *cred;
 241
 242         ff_layout_remove_mirror(mirror);
 243         kfree(mirror->fh_versions);
 244         cred = rcu_access_pointer(mirror->ro_cred);
 245         put_cred(cred);
 246         cred = rcu_access_pointer(mirror->rw_cred);
 247         put_cred(cred);
 248         nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 249         kfree(mirror);
 250 }
 251
 252 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 253 {
 254         if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
 255                 ff_layout_free_mirror(mirror);
 256 }
 257
 258 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 259 {
 260         u32 i;
 261
 262         for (i = 0; i < fls->mirror_array_cnt; i++)
 263                 ff_layout_put_mirror(fls->mirror_array[i]);
 264 }
 265
 266 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 267 {
 268         if (fls) {
 269                 ff_layout_free_mirror_array(fls);
 270                 kfree(fls);
 271         }
 272 }
 273
 274 static bool
 275 ff_lseg_match_mirrors(struct pnfs_layout_segment *l1,
 276                 struct pnfs_layout_segment *l2)
 277 {
 278         const struct nfs4_ff_layout_segment *fl1 = FF_LAYOUT_LSEG(l1);
 279         const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l1);
 280         u32 i;
 281
 282         if (fl1->mirror_array_cnt != fl2->mirror_array_cnt)
 283                 return false;
 284         for (i = 0; i < fl1->mirror_array_cnt; i++) {
 285                 if (fl1->mirror_array[i] != fl2->mirror_array[i])
 286                         return false;
 287         }
 288         return true;
 289 }
 290
 291 static bool
 292 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 293                 const struct pnfs_layout_range *l2)
 294 {
 295         u64 end1, end2;
 296
 297         if (l1->iomode != l2->iomode)
 298                 return l1->iomode != IOMODE_READ;
 299         end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 300         end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 301         if (end1 < l2->offset)
 302                 return false;
 303         if (end2 < l1->offset)
 304                 return true;
 305         return l2->offset <= l1->offset;
 306 }
 307
 308 static bool
 309 ff_lseg_merge(struct pnfs_layout_segment *new,
 310                 struct pnfs_layout_segment *old)
 311 {
 312         u64 new_end, old_end;
 313
 314         if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 315                 return false;
 316         if (new->pls_range.iomode != old->pls_range.iomode)
 317                 return false;
 318         old_end = pnfs_calc_offset_end(old->pls_range.offset,
 319                         old->pls_range.length);
 320         if (old_end < new->pls_range.offset)
 321                 return false;
 322         new_end = pnfs_calc_offset_end(new->pls_range.offset,
 323                         new->pls_range.length);
 324         if (new_end < old->pls_range.offset)
 325                 return false;
 326         if (!ff_lseg_match_mirrors(new, old))
 327                 return false;
 328
 329         /* Mergeable: copy info from 'old' to 'new' */
 330         if (new_end < old_end)
 331                 new_end = old_end;
 332         if (new->pls_range.offset < old->pls_range.offset)
 333                 new->pls_range.offset = old->pls_range.offset;
 334         new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 335                         new_end);
 336         if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 337                 set_bit(NFS_LSEG_ROC, &new->pls_flags);
 338         return true;
 339 }
 340
 341 static void
 342 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 343                 struct pnfs_layout_segment *lseg,
 344                 struct list_head *free_me)
 345 {
 346         pnfs_generic_layout_insert_lseg(lo, lseg,
 347                         ff_lseg_range_is_after,
 348                         ff_lseg_merge,
 349                         free_me);
 350 }
 351
 352 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 353 {
 354         int i, j;
 355
 356         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 357                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 358                         if (fls->mirror_array[i]->efficiency <
 359                             fls->mirror_array[j]->efficiency)
 360                                 swap(fls->mirror_array[i],
 361                                      fls->mirror_array[j]);
 362         }
 363 }
 364
 365 static struct pnfs_layout_segment *
 366 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 367                      struct nfs4_layoutget_res *lgr,
 368                      gfp_t gfp_flags)
 369 {
 370         struct pnfs_layout_segment *ret;
 371         struct nfs4_ff_layout_segment *fls = NULL;
 372         struct xdr_stream stream;
 373         struct xdr_buf buf;
 374         struct page *scratch;
 375         u64 stripe_unit;
 376         u32 mirror_array_cnt;
 377         __be32 *p;
 378         int i, rc;
 379
 380         dprintk("--> %s\n", __func__);
 381         scratch = alloc_page(gfp_flags);
 382         if (!scratch)
 383                 return ERR_PTR(-ENOMEM);
 384
 385         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 386                               lgr->layoutp->len);
 387         xdr_set_scratch_page(&stream, scratch);
 388
 389         /* stripe unit and mirror_array_cnt */
 390         rc = -EIO;
 391         p = xdr_inline_decode(&stream, 8 + 4);
 392         if (!p)
 393                 goto out_err_free;
 394
 395         p = xdr_decode_hyper(p, &stripe_unit);
 396         mirror_array_cnt = be32_to_cpup(p++);
 397         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 398                 stripe_unit, mirror_array_cnt);
 399
 400         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 401             mirror_array_cnt == 0)
 402                 goto out_err_free;
 403
 404         rc = -ENOMEM;
 405         fls = kzalloc(struct_size(fls, mirror_array, mirror_array_cnt),
 406                         gfp_flags);
 407         if (!fls)
 408                 goto out_err_free;
 409
 410         fls->mirror_array_cnt = mirror_array_cnt;
 411         fls->stripe_unit = stripe_unit;
 412
 413         for (i = 0; i < fls->mirror_array_cnt; i++) {
 414                 struct nfs4_ff_layout_mirror *mirror;
 415                 struct cred *kcred;
 416                 const struct cred __rcu *cred;
 417                 kuid_t uid;
 418                 kgid_t gid;
 419                 u32 ds_count, fh_count, id;
 420                 int j;
 421
 422                 rc = -EIO;
 423                 p = xdr_inline_decode(&stream, 4);
 424                 if (!p)
 425                         goto out_err_free;
 426                 ds_count = be32_to_cpup(p);
 427
 428                 /* FIXME: allow for striping? */
 429                 if (ds_count != 1)
 430                         goto out_err_free;
 431
 432                 fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 433                 if (fls->mirror_array[i] == NULL) {
 434                         rc = -ENOMEM;
 435                         goto out_err_free;
 436                 }
 437
 438                 fls->mirror_array[i]->ds_count = ds_count;
 439
 440                 /* deviceid */
 441                 rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
 442                 if (rc)
 443                         goto out_err_free;
 444
 445                 /* efficiency */
 446                 rc = -EIO;
 447                 p = xdr_inline_decode(&stream, 4);
 448                 if (!p)
 449                         goto out_err_free;
 450                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 451
 452                 /* stateid */
 453                 rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 454                 if (rc)
 455                         goto out_err_free;
 456
 457                 /* fh */
 458                 rc = -EIO;
 459                 p = xdr_inline_decode(&stream, 4);
 460                 if (!p)
 461                         goto out_err_free;
 462                 fh_count = be32_to_cpup(p);
 463
 464                 fls->mirror_array[i]->fh_versions =
 465                         kcalloc(fh_count, sizeof(struct nfs_fh),
 466                                 gfp_flags);
 467                 if (fls->mirror_array[i]->fh_versions == NULL) {
 468                         rc = -ENOMEM;
 469                         goto out_err_free;
 470                 }
 471
 472                 for (j = 0; j < fh_count; j++) {
 473                         rc = decode_nfs_fh(&stream,
 474                                            &fls->mirror_array[i]->fh_versions[j]);
 475                         if (rc)
 476                                 goto out_err_free;
 477                 }
 478
 479                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 480
 481                 /* user */
 482                 rc = decode_name(&stream, &id);
 483                 if (rc)
 484                         goto out_err_free;
 485
 486                 uid = make_kuid(&init_user_ns, id);
 487
 488                 /* group */
 489                 rc = decode_name(&stream, &id);
 490                 if (rc)
 491                         goto out_err_free;
 492
 493                 gid = make_kgid(&init_user_ns, id);
 494
 495                 if (gfp_flags & __GFP_FS)
 496                         kcred = prepare_kernel_cred(&init_task);
 497                 else {
 498                         unsigned int nofs_flags = memalloc_nofs_save();
 499                         kcred = prepare_kernel_cred(&init_task);
 500                         memalloc_nofs_restore(nofs_flags);
 501                 }
 502                 rc = -ENOMEM;
 503                 if (!kcred)
 504                         goto out_err_free;
 505                 kcred->fsuid = uid;
 506                 kcred->fsgid = gid;
 507                 cred = RCU_INITIALIZER(kcred);
 508
 509                 if (lgr->range.iomode == IOMODE_READ)
 510                         rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 511                 else
 512                         rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 513
 514                 mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 515                 if (mirror != fls->mirror_array[i]) {
 516                         /* swap cred ptrs so free_mirror will clean up old */
 517                         if (lgr->range.iomode == IOMODE_READ) {
 518                                 cred = xchg(&mirror->ro_cred, cred);
 519                                 rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 520                         } else {
 521                                 cred = xchg(&mirror->rw_cred, cred);
 522                                 rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 523                         }
 524                         ff_layout_free_mirror(fls->mirror_array[i]);
 525                         fls->mirror_array[i] = mirror;
 526                 }
 527
 528                 dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 529                         lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 530                         from_kuid(&init_user_ns, uid),
 531                         from_kgid(&init_user_ns, gid));
 532         }
 533
 534         p = xdr_inline_decode(&stream, 4);
 535         if (!p)
 536                 goto out_sort_mirrors;
 537         fls->flags = be32_to_cpup(p);
 538
 539         p = xdr_inline_decode(&stream, 4);
 540         if (!p)
 541                 goto out_sort_mirrors;
 542         for (i=0; i < fls->mirror_array_cnt; i++)
 543                 fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 544
 545 out_sort_mirrors:
 546         ff_layout_sort_mirrors(fls);
 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 void
 560 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 561 {
 562         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 563
 564         dprintk("--> %s\n", __func__);
 565
 566         if (lseg->pls_range.iomode == IOMODE_RW) {
 567                 struct nfs4_flexfile_layout *ffl;
 568                 struct inode *inode;
 569
 570                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 571                 inode = ffl->generic_hdr.plh_inode;
 572                 spin_lock(&inode->i_lock);
 573                 pnfs_generic_ds_cinfo_release_lseg(&ffl->commit_info, lseg);
 574                 spin_unlock(&inode->i_lock);
 575         }
 576         _ff_layout_free_lseg(fls);
 577 }
 578
 579 static void
 580 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 581 {
 582         /* first IO request? */
 583         if (atomic_inc_return(&timer->n_ops) == 1) {
 584                 timer->start_time = now;
 585         }
 586 }
 587
 588 static ktime_t
 589 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 590 {
 591         ktime_t start;
 592
 593         if (atomic_dec_return(&timer->n_ops) < 0)
 594                 WARN_ON_ONCE(1);
 595
 596         start = timer->start_time;
 597         timer->start_time = now;
 598         return ktime_sub(now, start);
 599 }
 600
 601 static bool
 602 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 603                             struct nfs4_ff_layoutstat *layoutstat,
 604                             ktime_t now)
 605 {
 606         s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 607         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 608
 609         nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 610         if (!mirror->start_time)
 611                 mirror->start_time = now;
 612         if (mirror->report_interval != 0)
 613                 report_interval = (s64)mirror->report_interval * 1000LL;
 614         else if (layoutstats_timer != 0)
 615                 report_interval = (s64)layoutstats_timer * 1000LL;
 616         if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 617                         report_interval) {
 618                 ffl->last_report_time = now;
 619                 return true;
 620         }
 621
 622         return false;
 623 }
 624
 625 static void
 626 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 627                 __u64 requested)
 628 {
 629         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 630
 631         iostat->ops_requested++;
 632         iostat->bytes_requested += requested;
 633 }
 634
 635 static void
 636 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 637                 __u64 requested,
 638                 __u64 completed,
 639                 ktime_t time_completed,
 640                 ktime_t time_started)
 641 {
 642         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 643         ktime_t completion_time = ktime_sub(time_completed, time_started);
 644         ktime_t timer;
 645
 646         iostat->ops_completed++;
 647         iostat->bytes_completed += completed;
 648         iostat->bytes_not_delivered += requested - completed;
 649
 650         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 651         iostat->total_busy_time =
 652                         ktime_add(iostat->total_busy_time, timer);
 653         iostat->aggregate_completion_time =
 654                         ktime_add(iostat->aggregate_completion_time,
 655                                         completion_time);
 656 }
 657
 658 static void
 659 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 660                 struct nfs4_ff_layout_mirror *mirror,
 661                 __u64 requested, ktime_t now)
 662 {
 663         bool report;
 664
 665         spin_lock(&mirror->lock);
 666         report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 667         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 668         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 669         spin_unlock(&mirror->lock);
 670
 671         if (report)
 672                 pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
 673 }
 674
 675 static void
 676 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 677                 struct nfs4_ff_layout_mirror *mirror,
 678                 __u64 requested,
 679                 __u64 completed)
 680 {
 681         spin_lock(&mirror->lock);
 682         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 683                         requested, completed,
 684                         ktime_get(), task->tk_start);
 685         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 686         spin_unlock(&mirror->lock);
 687 }
 688
 689 static void
 690 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 691                 struct nfs4_ff_layout_mirror *mirror,
 692                 __u64 requested, ktime_t now)
 693 {
 694         bool report;
 695
 696         spin_lock(&mirror->lock);
 697         report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 698         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 699         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 700         spin_unlock(&mirror->lock);
 701
 702         if (report)
 703                 pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
 704 }
 705
 706 static void
 707 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 708                 struct nfs4_ff_layout_mirror *mirror,
 709                 __u64 requested,
 710                 __u64 completed,
 711                 enum nfs3_stable_how committed)
 712 {
 713         if (committed == NFS_UNSTABLE)
 714                 requested = completed = 0;
 715
 716         spin_lock(&mirror->lock);
 717         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 718                         requested, completed, ktime_get(), task->tk_start);
 719         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 720         spin_unlock(&mirror->lock);
 721 }
 722
 723 static void
 724 ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx)
 725 {
 726         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 727
 728         if (devid)
 729                 nfs4_mark_deviceid_unavailable(devid);
 730 }
 731
 732 static void
 733 ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx)
 734 {
 735         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 736
 737         if (devid)
 738                 nfs4_mark_deviceid_available(devid);
 739 }
 740
 741 static struct nfs4_pnfs_ds *
 742 ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 743                              u32 start_idx, u32 *best_idx,
 744                              bool check_device)
 745 {
 746         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 747         struct nfs4_ff_layout_mirror *mirror;
 748         struct nfs4_pnfs_ds *ds;
 749         u32 idx;
 750
 751         /* mirrors are initially sorted by efficiency */
 752         for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 753                 mirror = FF_LAYOUT_COMP(lseg, idx);
 754                 ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
 755                 if (!ds)
 756                         continue;
 757
 758                 if (check_device &&
 759                     nfs4_test_deviceid_unavailable(&mirror->mirror_ds->id_node))
 760                         continue;
 761
 762                 *best_idx = idx;
 763                 return ds;
 764         }
 765
 766         return NULL;
 767 }
 768
 769 static struct nfs4_pnfs_ds *
 770 ff_layout_choose_any_ds_for_read(struct pnfs_layout_segment *lseg,
 771                                  u32 start_idx, u32 *best_idx)
 772 {
 773         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, false);
 774 }
 775
 776 static struct nfs4_pnfs_ds *
 777 ff_layout_choose_valid_ds_for_read(struct pnfs_layout_segment *lseg,
 778                                    u32 start_idx, u32 *best_idx)
 779 {
 780         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, true);
 781 }
 782
 783 static struct nfs4_pnfs_ds *
 784 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 785                                   u32 start_idx, u32 *best_idx)
 786 {
 787         struct nfs4_pnfs_ds *ds;
 788
 789         ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx);
 790         if (ds)
 791                 return ds;
 792         return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx);
 793 }
 794
 795 static struct nfs4_pnfs_ds *
 796 ff_layout_get_ds_for_read(struct nfs_pageio_descriptor *pgio,
 797                           u32 *best_idx)
 798 {
 799         struct pnfs_layout_segment *lseg = pgio->pg_lseg;
 800         struct nfs4_pnfs_ds *ds;
 801
 802         ds = ff_layout_choose_best_ds_for_read(lseg, pgio->pg_mirror_idx,
 803                                                best_idx);
 804         if (ds || !pgio->pg_mirror_idx)
 805                 return ds;
 806         return ff_layout_choose_best_ds_for_read(lseg, 0, best_idx);
 807 }
 808
 809 static void
 810 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 811                       struct nfs_page *req,
 812                       bool strict_iomode)
 813 {
 814         pnfs_put_lseg(pgio->pg_lseg);
 815         pgio->pg_lseg =
 816                 pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
 817                                    req_offset(req), req->wb_bytes, IOMODE_READ,
 818                                    strict_iomode, nfs_io_gfp_mask());
 819         if (IS_ERR(pgio->pg_lseg)) {
 820                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 821                 pgio->pg_lseg = NULL;
 822         }
 823 }
 824
 825 static void
 826 ff_layout_pg_check_layout(struct nfs_pageio_descriptor *pgio,
 827                           struct nfs_page *req)
 828 {
 829         pnfs_generic_pg_check_layout(pgio);
 830         pnfs_generic_pg_check_range(pgio, req);
 831 }
 832
 833 static void
 834 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 835                         struct nfs_page *req)
 836 {
 837         struct nfs_pgio_mirror *pgm;
 838         struct nfs4_ff_layout_mirror *mirror;
 839         struct nfs4_pnfs_ds *ds;
 840         u32 ds_idx;
 841
 842 retry:
 843         ff_layout_pg_check_layout(pgio, req);
 844         /* Use full layout for now */
 845         if (!pgio->pg_lseg) {
 846                 ff_layout_pg_get_read(pgio, req, false);
 847                 if (!pgio->pg_lseg)
 848                         goto out_nolseg;
 849         }
 850         if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 851                 ff_layout_pg_get_read(pgio, req, true);
 852                 if (!pgio->pg_lseg)
 853                         goto out_nolseg;
 854         }
 855
 856         ds = ff_layout_get_ds_for_read(pgio, &ds_idx);
 857         if (!ds) {
 858                 if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 859                         goto out_mds;
 860                 pnfs_generic_pg_cleanup(pgio);
 861                 /* Sleep for 1 second before retrying */
 862                 ssleep(1);
 863                 goto retry;
 864         }
 865
 866         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 867         pgm = &pgio->pg_mirrors[0];
 868         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 869
 870         pgio->pg_mirror_idx = ds_idx;
 871
 872         if (NFS_SERVER(pgio->pg_inode)->flags &
 873                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 874                 pgio->pg_maxretrans = io_maxretrans;
 875         return;
 876 out_nolseg:
 877         if (pgio->pg_error < 0)
 878                 return;
 879 out_mds:
 880         trace_pnfs_mds_fallback_pg_init_read(pgio->pg_inode,
 881                         0, NFS4_MAX_UINT64, IOMODE_READ,
 882                         NFS_I(pgio->pg_inode)->layout,
 883                         pgio->pg_lseg);
 884         pgio->pg_maxretrans = 0;
 885         nfs_pageio_reset_read_mds(pgio);
 886 }
 887
 888 static void
 889 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 890                         struct nfs_page *req)
 891 {
 892         struct nfs4_ff_layout_mirror *mirror;
 893         struct nfs_pgio_mirror *pgm;
 894         struct nfs4_pnfs_ds *ds;
 895         u32 i;
 896
 897 retry:
 898         ff_layout_pg_check_layout(pgio, req);
 899         if (!pgio->pg_lseg) {
 900                 pgio->pg_lseg =
 901                         pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
 902                                            req_offset(req), req->wb_bytes,
 903                                            IOMODE_RW, false, nfs_io_gfp_mask());
 904                 if (IS_ERR(pgio->pg_lseg)) {
 905                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 906                         pgio->pg_lseg = NULL;
 907                         return;
 908                 }
 909         }
 910         /* If no lseg, fall back to write through mds */
 911         if (pgio->pg_lseg == NULL)
 912                 goto out_mds;
 913
 914         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 915         if (pgio->pg_mirror_count != FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg))
 916                 goto out_eagain;
 917
 918         for (i = 0; i < pgio->pg_mirror_count; i++) {
 919                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 920                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
 921                 if (!ds) {
 922                         if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 923                                 goto out_mds;
 924                         pnfs_generic_pg_cleanup(pgio);
 925                         /* Sleep for 1 second before retrying */
 926                         ssleep(1);
 927                         goto retry;
 928                 }
 929                 pgm = &pgio->pg_mirrors[i];
 930                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 931         }
 932
 933         if (NFS_SERVER(pgio->pg_inode)->flags &
 934                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 935                 pgio->pg_maxretrans = io_maxretrans;
 936         return;
 937 out_eagain:
 938         pnfs_generic_pg_cleanup(pgio);
 939         pgio->pg_error = -EAGAIN;
 940         return;
 941 out_mds:
 942         trace_pnfs_mds_fallback_pg_init_write(pgio->pg_inode,
 943                         0, NFS4_MAX_UINT64, IOMODE_RW,
 944                         NFS_I(pgio->pg_inode)->layout,
 945                         pgio->pg_lseg);
 946         pgio->pg_maxretrans = 0;
 947         nfs_pageio_reset_write_mds(pgio);
 948         pgio->pg_error = -EAGAIN;
 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 =
 957                         pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
 958                                            req_offset(req), req->wb_bytes,
 959                                            IOMODE_RW, false, nfs_io_gfp_mask());
 960                 if (IS_ERR(pgio->pg_lseg)) {
 961                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 962                         pgio->pg_lseg = NULL;
 963                         goto out;
 964                 }
 965         }
 966         if (pgio->pg_lseg)
 967                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 968
 969         trace_pnfs_mds_fallback_pg_get_mirror_count(pgio->pg_inode,
 970                         0, NFS4_MAX_UINT64, IOMODE_RW,
 971                         NFS_I(pgio->pg_inode)->layout,
 972                         pgio->pg_lseg);
 973         /* no lseg means that pnfs is not in use, so no mirroring here */
 974         nfs_pageio_reset_write_mds(pgio);
 975 out:
 976         return 1;
 977 }
 978
 979 static u32
 980 ff_layout_pg_set_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 981 {
 982         u32 old = desc->pg_mirror_idx;
 983
 984         desc->pg_mirror_idx = idx;
 985         return old;
 986 }
 987
 988 static struct nfs_pgio_mirror *
 989 ff_layout_pg_get_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 990 {
 991         return &desc->pg_mirrors[idx];
 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         .pg_get_mirror = ff_layout_pg_get_mirror_write,
1008         .pg_set_mirror = ff_layout_pg_set_mirror_write,
1009 };
1010
1011 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1012 {
1013         struct rpc_task *task = &hdr->task;
1014
1015         pnfs_layoutcommit_inode(hdr->inode, false);
1016
1017         if (retry_pnfs) {
1018                 dprintk("%s Reset task %5u for i/o through pNFS "
1019                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1020                         hdr->task.tk_pid,
1021                         hdr->inode->i_sb->s_id,
1022                         (unsigned long long)NFS_FILEID(hdr->inode),
1023                         hdr->args.count,
1024                         (unsigned long long)hdr->args.offset);
1025
1026                 hdr->completion_ops->reschedule_io(hdr);
1027                 return;
1028         }
1029
1030         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1031                 dprintk("%s Reset task %5u for i/o through MDS "
1032                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1033                         hdr->task.tk_pid,
1034                         hdr->inode->i_sb->s_id,
1035                         (unsigned long long)NFS_FILEID(hdr->inode),
1036                         hdr->args.count,
1037                         (unsigned long long)hdr->args.offset);
1038
1039                 trace_pnfs_mds_fallback_write_done(hdr->inode,
1040                                 hdr->args.offset, hdr->args.count,
1041                                 IOMODE_RW, NFS_I(hdr->inode)->layout,
1042                                 hdr->lseg);
1043                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1044         }
1045 }
1046
1047 static void ff_layout_resend_pnfs_read(struct nfs_pgio_header *hdr)
1048 {
1049         u32 idx = hdr->pgio_mirror_idx + 1;
1050         u32 new_idx = 0;
1051
1052         if (ff_layout_choose_any_ds_for_read(hdr->lseg, idx, &new_idx))
1053                 ff_layout_send_layouterror(hdr->lseg);
1054         else
1055                 pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1056         pnfs_read_resend_pnfs(hdr, new_idx);
1057 }
1058
1059 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1060 {
1061         struct rpc_task *task = &hdr->task;
1062
1063         pnfs_layoutcommit_inode(hdr->inode, false);
1064         pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1065
1066         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1067                 dprintk("%s Reset task %5u for i/o through MDS "
1068                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1069                         hdr->task.tk_pid,
1070                         hdr->inode->i_sb->s_id,
1071                         (unsigned long long)NFS_FILEID(hdr->inode),
1072                         hdr->args.count,
1073                         (unsigned long long)hdr->args.offset);
1074
1075                 trace_pnfs_mds_fallback_read_done(hdr->inode,
1076                                 hdr->args.offset, hdr->args.count,
1077                                 IOMODE_READ, NFS_I(hdr->inode)->layout,
1078                                 hdr->lseg);
1079                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1080         }
1081 }
1082
1083 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1084                                            struct nfs4_state *state,
1085                                            struct nfs_client *clp,
1086                                            struct pnfs_layout_segment *lseg,
1087                                            u32 idx)
1088 {
1089         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1090         struct inode *inode = lo->plh_inode;
1091         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1092         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1093
1094         switch (task->tk_status) {
1095         case -NFS4ERR_BADSESSION:
1096         case -NFS4ERR_BADSLOT:
1097         case -NFS4ERR_BAD_HIGH_SLOT:
1098         case -NFS4ERR_DEADSESSION:
1099         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1100         case -NFS4ERR_SEQ_FALSE_RETRY:
1101         case -NFS4ERR_SEQ_MISORDERED:
1102                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1103                         "flags 0x%x\n", __func__, task->tk_status,
1104                         clp->cl_exchange_flags);
1105                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1106                 break;
1107         case -NFS4ERR_DELAY:
1108         case -NFS4ERR_GRACE:
1109                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1110                 break;
1111         case -NFS4ERR_RETRY_UNCACHED_REP:
1112                 break;
1113         /* Invalidate Layout errors */
1114         case -NFS4ERR_PNFS_NO_LAYOUT:
1115         case -ESTALE:           /* mapped NFS4ERR_STALE */
1116         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1117         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1118         case -NFS4ERR_FHEXPIRED:
1119         case -NFS4ERR_WRONG_TYPE:
1120                 dprintk("%s Invalid layout error %d\n", __func__,
1121                         task->tk_status);
1122                 /*
1123                  * Destroy layout so new i/o will get a new layout.
1124                  * Layout will not be destroyed until all current lseg
1125                  * references are put. Mark layout as invalid to resend failed
1126                  * i/o and all i/o waiting on the slot table to the MDS until
1127                  * layout is destroyed and a new valid layout is obtained.
1128                  */
1129                 pnfs_destroy_layout(NFS_I(inode));
1130                 rpc_wake_up(&tbl->slot_tbl_waitq);
1131                 goto reset;
1132         /* RPC connection errors */
1133         case -ECONNREFUSED:
1134         case -EHOSTDOWN:
1135         case -EHOSTUNREACH:
1136         case -ENETUNREACH:
1137         case -EIO:
1138         case -ETIMEDOUT:
1139         case -EPIPE:
1140         case -EPROTO:
1141         case -ENODEV:
1142                 dprintk("%s DS connection error %d\n", __func__,
1143                         task->tk_status);
1144                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1145                                 &devid->deviceid);
1146                 rpc_wake_up(&tbl->slot_tbl_waitq);
1147                 fallthrough;
1148         default:
1149                 if (ff_layout_avoid_mds_available_ds(lseg))
1150                         return -NFS4ERR_RESET_TO_PNFS;
1151 reset:
1152                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1153                         task->tk_status);
1154                 return -NFS4ERR_RESET_TO_MDS;
1155         }
1156         task->tk_status = 0;
1157         return -EAGAIN;
1158 }
1159
1160 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1161 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1162                                            struct pnfs_layout_segment *lseg,
1163                                            u32 idx)
1164 {
1165         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1166
1167         switch (task->tk_status) {
1168         /* File access problems. Don't mark the device as unavailable */
1169         case -EACCES:
1170         case -ESTALE:
1171         case -EISDIR:
1172         case -EBADHANDLE:
1173         case -ELOOP:
1174         case -ENOSPC:
1175                 break;
1176         case -EJUKEBOX:
1177                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1178                 goto out_retry;
1179         default:
1180                 dprintk("%s DS connection error %d\n", __func__,
1181                         task->tk_status);
1182                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1183                                 &devid->deviceid);
1184         }
1185         /* FIXME: Need to prevent infinite looping here. */
1186         return -NFS4ERR_RESET_TO_PNFS;
1187 out_retry:
1188         task->tk_status = 0;
1189         rpc_restart_call_prepare(task);
1190         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1191         return -EAGAIN;
1192 }
1193
1194 static int ff_layout_async_handle_error(struct rpc_task *task,
1195                                         struct nfs4_state *state,
1196                                         struct nfs_client *clp,
1197                                         struct pnfs_layout_segment *lseg,
1198                                         u32 idx)
1199 {
1200         int vers = clp->cl_nfs_mod->rpc_vers->number;
1201
1202         if (task->tk_status >= 0) {
1203                 ff_layout_mark_ds_reachable(lseg, idx);
1204                 return 0;
1205         }
1206
1207         /* Handle the case of an invalid layout segment */
1208         if (!pnfs_is_valid_lseg(lseg))
1209                 return -NFS4ERR_RESET_TO_PNFS;
1210
1211         switch (vers) {
1212         case 3:
1213                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1214         case 4:
1215                 return ff_layout_async_handle_error_v4(task, state, clp,
1216                                                        lseg, idx);
1217         default:
1218                 /* should never happen */
1219                 WARN_ON_ONCE(1);
1220                 return 0;
1221         }
1222 }
1223
1224 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1225                                         u32 idx, u64 offset, u64 length,
1226                                         u32 *op_status, int opnum, int error)
1227 {
1228         struct nfs4_ff_layout_mirror *mirror;
1229         u32 status = *op_status;
1230         int err;
1231
1232         if (status == 0) {
1233                 switch (error) {
1234                 case -ETIMEDOUT:
1235                 case -EPFNOSUPPORT:
1236                 case -EPROTONOSUPPORT:
1237                 case -EOPNOTSUPP:
1238                 case -ECONNREFUSED:
1239                 case -ECONNRESET:
1240                 case -EHOSTDOWN:
1241                 case -EHOSTUNREACH:
1242                 case -ENETUNREACH:
1243                 case -EADDRINUSE:
1244                 case -ENOBUFS:
1245                 case -EPIPE:
1246                 case -EPERM:
1247                 case -EPROTO:
1248                 case -ENODEV:
1249                         *op_status = status = NFS4ERR_NXIO;
1250                         break;
1251                 case -EACCES:
1252                         *op_status = status = NFS4ERR_ACCESS;
1253                         break;
1254                 default:
1255                         return;
1256                 }
1257         }
1258
1259         mirror = FF_LAYOUT_COMP(lseg, idx);
1260         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1261                                        mirror, offset, length, status, opnum,
1262                                        nfs_io_gfp_mask());
1263
1264         switch (status) {
1265         case NFS4ERR_DELAY:
1266         case NFS4ERR_GRACE:
1267                 break;
1268         case NFS4ERR_NXIO:
1269                 ff_layout_mark_ds_unreachable(lseg, idx);
1270                 /*
1271                  * Don't return the layout if this is a read and we still
1272                  * have layouts to try
1273                  */
1274                 if (opnum == OP_READ)
1275                         break;
1276                 fallthrough;
1277         default:
1278                 pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode,
1279                                                   lseg);
1280         }
1281
1282         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1283 }
1284
1285 /* NFS_PROTO call done callback routines */
1286 static int ff_layout_read_done_cb(struct rpc_task *task,
1287                                 struct nfs_pgio_header *hdr)
1288 {
1289         int err;
1290
1291         if (task->tk_status < 0) {
1292                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1293                                             hdr->args.offset, hdr->args.count,
1294                                             &hdr->res.op_status, OP_READ,
1295                                             task->tk_status);
1296                 trace_ff_layout_read_error(hdr);
1297         }
1298
1299         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1300                                            hdr->ds_clp, hdr->lseg,
1301                                            hdr->pgio_mirror_idx);
1302
1303         trace_nfs4_pnfs_read(hdr, err);
1304         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1305         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1306         switch (err) {
1307         case -NFS4ERR_RESET_TO_PNFS:
1308                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1309                 return task->tk_status;
1310         case -NFS4ERR_RESET_TO_MDS:
1311                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1312                 return task->tk_status;
1313         case -EAGAIN:
1314                 goto out_eagain;
1315         }
1316
1317         return 0;
1318 out_eagain:
1319         rpc_restart_call_prepare(task);
1320         return -EAGAIN;
1321 }
1322
1323 static bool
1324 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1325 {
1326         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1327 }
1328
1329 /*
1330  * We reference the rpc_cred of the first WRITE that triggers the need for
1331  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1332  * rfc5661 is not clear about which credential should be used.
1333  *
1334  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1335  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1336  * we always send layoutcommit after DS writes.
1337  */
1338 static void
1339 ff_layout_set_layoutcommit(struct inode *inode,
1340                 struct pnfs_layout_segment *lseg,
1341                 loff_t end_offset)
1342 {
1343         if (!ff_layout_need_layoutcommit(lseg))
1344                 return;
1345
1346         pnfs_set_layoutcommit(inode, lseg, end_offset);
1347         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1348                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1349 }
1350
1351 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1352                 struct nfs_pgio_header *hdr)
1353 {
1354         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1355                 return;
1356         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1357                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1358                         hdr->args.count,
1359                         task->tk_start);
1360 }
1361
1362 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1363                 struct nfs_pgio_header *hdr)
1364 {
1365         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1366                 return;
1367         nfs4_ff_layout_stat_io_end_read(task,
1368                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1369                         hdr->args.count,
1370                         hdr->res.count);
1371         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1372 }
1373
1374 static int ff_layout_read_prepare_common(struct rpc_task *task,
1375                                          struct nfs_pgio_header *hdr)
1376 {
1377         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1378                 rpc_exit(task, -EIO);
1379                 return -EIO;
1380         }
1381
1382         if (!pnfs_is_valid_lseg(hdr->lseg)) {
1383                 rpc_exit(task, -EAGAIN);
1384                 return -EAGAIN;
1385         }
1386
1387         ff_layout_read_record_layoutstats_start(task, hdr);
1388         return 0;
1389 }
1390
1391 /*
1392  * Call ops for the async read/write cases
1393  * In the case of dense layouts, the offset needs to be reset to its
1394  * original value.
1395  */
1396 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1397 {
1398         struct nfs_pgio_header *hdr = data;
1399
1400         if (ff_layout_read_prepare_common(task, hdr))
1401                 return;
1402
1403         rpc_call_start(task);
1404 }
1405
1406 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1407 {
1408         struct nfs_pgio_header *hdr = data;
1409
1410         if (nfs4_setup_sequence(hdr->ds_clp,
1411                                 &hdr->args.seq_args,
1412                                 &hdr->res.seq_res,
1413                                 task))
1414                 return;
1415
1416         ff_layout_read_prepare_common(task, hdr);
1417 }
1418
1419 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1420 {
1421         struct nfs_pgio_header *hdr = data;
1422
1423         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1424             task->tk_status == 0) {
1425                 nfs4_sequence_done(task, &hdr->res.seq_res);
1426                 return;
1427         }
1428
1429         /* Note this may cause RPC to be resent */
1430         hdr->mds_ops->rpc_call_done(task, hdr);
1431 }
1432
1433 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1434 {
1435         struct nfs_pgio_header *hdr = data;
1436
1437         ff_layout_read_record_layoutstats_done(task, hdr);
1438         rpc_count_iostats_metrics(task,
1439             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1440 }
1441
1442 static void ff_layout_read_release(void *data)
1443 {
1444         struct nfs_pgio_header *hdr = data;
1445
1446         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1447         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags))
1448                 ff_layout_resend_pnfs_read(hdr);
1449         else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1450                 ff_layout_reset_read(hdr);
1451         pnfs_generic_rw_release(data);
1452 }
1453
1454
1455 static int ff_layout_write_done_cb(struct rpc_task *task,
1456                                 struct nfs_pgio_header *hdr)
1457 {
1458         loff_t end_offs = 0;
1459         int err;
1460
1461         if (task->tk_status < 0) {
1462                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1463                                             hdr->args.offset, hdr->args.count,
1464                                             &hdr->res.op_status, OP_WRITE,
1465                                             task->tk_status);
1466                 trace_ff_layout_write_error(hdr);
1467         }
1468
1469         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1470                                            hdr->ds_clp, hdr->lseg,
1471                                            hdr->pgio_mirror_idx);
1472
1473         trace_nfs4_pnfs_write(hdr, err);
1474         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1475         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1476         switch (err) {
1477         case -NFS4ERR_RESET_TO_PNFS:
1478                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1479                 return task->tk_status;
1480         case -NFS4ERR_RESET_TO_MDS:
1481                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1482                 return task->tk_status;
1483         case -EAGAIN:
1484                 return -EAGAIN;
1485         }
1486
1487         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1488             hdr->res.verf->committed == NFS_DATA_SYNC)
1489                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1490
1491         /* Note: if the write is unstable, don't set end_offs until commit */
1492         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1493
1494         /* zero out fattr since we don't care DS attr at all */
1495         hdr->fattr.valid = 0;
1496         if (task->tk_status >= 0)
1497                 nfs_writeback_update_inode(hdr);
1498
1499         return 0;
1500 }
1501
1502 static int ff_layout_commit_done_cb(struct rpc_task *task,
1503                                      struct nfs_commit_data *data)
1504 {
1505         int err;
1506
1507         if (task->tk_status < 0) {
1508                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1509                                             data->args.offset, data->args.count,
1510                                             &data->res.op_status, OP_COMMIT,
1511                                             task->tk_status);
1512                 trace_ff_layout_commit_error(data);
1513         }
1514
1515         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1516                                            data->lseg, data->ds_commit_index);
1517
1518         trace_nfs4_pnfs_commit_ds(data, err);
1519         switch (err) {
1520         case -NFS4ERR_RESET_TO_PNFS:
1521                 pnfs_generic_prepare_to_resend_writes(data);
1522                 return -EAGAIN;
1523         case -NFS4ERR_RESET_TO_MDS:
1524                 pnfs_generic_prepare_to_resend_writes(data);
1525                 return -EAGAIN;
1526         case -EAGAIN:
1527                 rpc_restart_call_prepare(task);
1528                 return -EAGAIN;
1529         }
1530
1531         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1532
1533         return 0;
1534 }
1535
1536 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1537                 struct nfs_pgio_header *hdr)
1538 {
1539         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1540                 return;
1541         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1542                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1543                         hdr->args.count,
1544                         task->tk_start);
1545 }
1546
1547 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1548                 struct nfs_pgio_header *hdr)
1549 {
1550         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1551                 return;
1552         nfs4_ff_layout_stat_io_end_write(task,
1553                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1554                         hdr->args.count, hdr->res.count,
1555                         hdr->res.verf->committed);
1556         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1557 }
1558
1559 static int ff_layout_write_prepare_common(struct rpc_task *task,
1560                                           struct nfs_pgio_header *hdr)
1561 {
1562         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1563                 rpc_exit(task, -EIO);
1564                 return -EIO;
1565         }
1566
1567         if (!pnfs_is_valid_lseg(hdr->lseg)) {
1568                 rpc_exit(task, -EAGAIN);
1569                 return -EAGAIN;
1570         }
1571
1572         ff_layout_write_record_layoutstats_start(task, hdr);
1573         return 0;
1574 }
1575
1576 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1577 {
1578         struct nfs_pgio_header *hdr = data;
1579
1580         if (ff_layout_write_prepare_common(task, hdr))
1581                 return;
1582
1583         rpc_call_start(task);
1584 }
1585
1586 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1587 {
1588         struct nfs_pgio_header *hdr = data;
1589
1590         if (nfs4_setup_sequence(hdr->ds_clp,
1591                                 &hdr->args.seq_args,
1592                                 &hdr->res.seq_res,
1593                                 task))
1594                 return;
1595
1596         ff_layout_write_prepare_common(task, hdr);
1597 }
1598
1599 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1600 {
1601         struct nfs_pgio_header *hdr = data;
1602
1603         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1604             task->tk_status == 0) {
1605                 nfs4_sequence_done(task, &hdr->res.seq_res);
1606                 return;
1607         }
1608
1609         /* Note this may cause RPC to be resent */
1610         hdr->mds_ops->rpc_call_done(task, hdr);
1611 }
1612
1613 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1614 {
1615         struct nfs_pgio_header *hdr = data;
1616
1617         ff_layout_write_record_layoutstats_done(task, hdr);
1618         rpc_count_iostats_metrics(task,
1619             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1620 }
1621
1622 static void ff_layout_write_release(void *data)
1623 {
1624         struct nfs_pgio_header *hdr = data;
1625
1626         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1627         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1628                 ff_layout_send_layouterror(hdr->lseg);
1629                 ff_layout_reset_write(hdr, true);
1630         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1631                 ff_layout_reset_write(hdr, false);
1632         pnfs_generic_rw_release(data);
1633 }
1634
1635 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1636                 struct nfs_commit_data *cdata)
1637 {
1638         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1639                 return;
1640         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1641                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1642                         0, task->tk_start);
1643 }
1644
1645 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1646                 struct nfs_commit_data *cdata)
1647 {
1648         struct nfs_page *req;
1649         __u64 count = 0;
1650
1651         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1652                 return;
1653
1654         if (task->tk_status == 0) {
1655                 list_for_each_entry(req, &cdata->pages, wb_list)
1656                         count += req->wb_bytes;
1657         }
1658         nfs4_ff_layout_stat_io_end_write(task,
1659                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1660                         count, count, NFS_FILE_SYNC);
1661         set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1662 }
1663
1664 static int ff_layout_commit_prepare_common(struct rpc_task *task,
1665                                            struct nfs_commit_data *cdata)
1666 {
1667         if (!pnfs_is_valid_lseg(cdata->lseg)) {
1668                 rpc_exit(task, -EAGAIN);
1669                 return -EAGAIN;
1670         }
1671
1672         ff_layout_commit_record_layoutstats_start(task, cdata);
1673         return 0;
1674 }
1675
1676 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1677 {
1678         if (ff_layout_commit_prepare_common(task, data))
1679                 return;
1680
1681         rpc_call_start(task);
1682 }
1683
1684 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1685 {
1686         struct nfs_commit_data *wdata = data;
1687
1688         if (nfs4_setup_sequence(wdata->ds_clp,
1689                                 &wdata->args.seq_args,
1690                                 &wdata->res.seq_res,
1691                                 task))
1692                 return;
1693         ff_layout_commit_prepare_common(task, data);
1694 }
1695
1696 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1697 {
1698         pnfs_generic_write_commit_done(task, data);
1699 }
1700
1701 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1702 {
1703         struct nfs_commit_data *cdata = data;
1704
1705         ff_layout_commit_record_layoutstats_done(task, cdata);
1706         rpc_count_iostats_metrics(task,
1707             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1708 }
1709
1710 static void ff_layout_commit_release(void *data)
1711 {
1712         struct nfs_commit_data *cdata = data;
1713
1714         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1715         pnfs_generic_commit_release(data);
1716 }
1717
1718 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1719         .rpc_call_prepare = ff_layout_read_prepare_v3,
1720         .rpc_call_done = ff_layout_read_call_done,
1721         .rpc_count_stats = ff_layout_read_count_stats,
1722         .rpc_release = ff_layout_read_release,
1723 };
1724
1725 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1726         .rpc_call_prepare = ff_layout_read_prepare_v4,
1727         .rpc_call_done = ff_layout_read_call_done,
1728         .rpc_count_stats = ff_layout_read_count_stats,
1729         .rpc_release = ff_layout_read_release,
1730 };
1731
1732 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1733         .rpc_call_prepare = ff_layout_write_prepare_v3,
1734         .rpc_call_done = ff_layout_write_call_done,
1735         .rpc_count_stats = ff_layout_write_count_stats,
1736         .rpc_release = ff_layout_write_release,
1737 };
1738
1739 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1740         .rpc_call_prepare = ff_layout_write_prepare_v4,
1741         .rpc_call_done = ff_layout_write_call_done,
1742         .rpc_count_stats = ff_layout_write_count_stats,
1743         .rpc_release = ff_layout_write_release,
1744 };
1745
1746 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1747         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1748         .rpc_call_done = ff_layout_commit_done,
1749         .rpc_count_stats = ff_layout_commit_count_stats,
1750         .rpc_release = ff_layout_commit_release,
1751 };
1752
1753 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1754         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1755         .rpc_call_done = ff_layout_commit_done,
1756         .rpc_count_stats = ff_layout_commit_count_stats,
1757         .rpc_release = ff_layout_commit_release,
1758 };
1759
1760 static enum pnfs_try_status
1761 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1762 {
1763         struct pnfs_layout_segment *lseg = hdr->lseg;
1764         struct nfs4_pnfs_ds *ds;
1765         struct rpc_clnt *ds_clnt;
1766         struct nfs4_ff_layout_mirror *mirror;
1767         const struct cred *ds_cred;
1768         loff_t offset = hdr->args.offset;
1769         u32 idx = hdr->pgio_mirror_idx;
1770         int vers;
1771         struct nfs_fh *fh;
1772
1773         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1774                 __func__, hdr->inode->i_ino,
1775                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1776
1777         mirror = FF_LAYOUT_COMP(lseg, idx);
1778         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
1779         if (!ds)
1780                 goto out_failed;
1781
1782         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1783                                                    hdr->inode);
1784         if (IS_ERR(ds_clnt))
1785                 goto out_failed;
1786
1787         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1788         if (!ds_cred)
1789                 goto out_failed;
1790
1791         vers = nfs4_ff_layout_ds_version(mirror);
1792
1793         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1794                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1795
1796         hdr->pgio_done_cb = ff_layout_read_done_cb;
1797         refcount_inc(&ds->ds_clp->cl_count);
1798         hdr->ds_clp = ds->ds_clp;
1799         fh = nfs4_ff_layout_select_ds_fh(mirror);
1800         if (fh)
1801                 hdr->args.fh = fh;
1802
1803         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1804
1805         /*
1806          * Note that if we ever decide to split across DSes,
1807          * then we may need to handle dense-like offsets.
1808          */
1809         hdr->args.offset = offset;
1810         hdr->mds_offset = offset;
1811
1812         /* Perform an asynchronous read to ds */
1813         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1814                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1815                                       &ff_layout_read_call_ops_v4,
1816                           0, RPC_TASK_SOFTCONN);
1817         put_cred(ds_cred);
1818         return PNFS_ATTEMPTED;
1819
1820 out_failed:
1821         if (ff_layout_avoid_mds_available_ds(lseg))
1822                 return PNFS_TRY_AGAIN;
1823         trace_pnfs_mds_fallback_read_pagelist(hdr->inode,
1824                         hdr->args.offset, hdr->args.count,
1825                         IOMODE_READ, NFS_I(hdr->inode)->layout, lseg);
1826         return PNFS_NOT_ATTEMPTED;
1827 }
1828
1829 /* Perform async writes. */
1830 static enum pnfs_try_status
1831 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1832 {
1833         struct pnfs_layout_segment *lseg = hdr->lseg;
1834         struct nfs4_pnfs_ds *ds;
1835         struct rpc_clnt *ds_clnt;
1836         struct nfs4_ff_layout_mirror *mirror;
1837         const struct cred *ds_cred;
1838         loff_t offset = hdr->args.offset;
1839         int vers;
1840         struct nfs_fh *fh;
1841         u32 idx = hdr->pgio_mirror_idx;
1842
1843         mirror = FF_LAYOUT_COMP(lseg, idx);
1844         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1845         if (!ds)
1846                 goto out_failed;
1847
1848         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1849                                                    hdr->inode);
1850         if (IS_ERR(ds_clnt))
1851                 goto out_failed;
1852
1853         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1854         if (!ds_cred)
1855                 goto out_failed;
1856
1857         vers = nfs4_ff_layout_ds_version(mirror);
1858
1859         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1860                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1861                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1862                 vers);
1863
1864         hdr->pgio_done_cb = ff_layout_write_done_cb;
1865         refcount_inc(&ds->ds_clp->cl_count);
1866         hdr->ds_clp = ds->ds_clp;
1867         hdr->ds_commit_idx = idx;
1868         fh = nfs4_ff_layout_select_ds_fh(mirror);
1869         if (fh)
1870                 hdr->args.fh = fh;
1871
1872         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1873
1874         /*
1875          * Note that if we ever decide to split across DSes,
1876          * then we may need to handle dense-like offsets.
1877          */
1878         hdr->args.offset = offset;
1879
1880         /* Perform an asynchronous write */
1881         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1882                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1883                                       &ff_layout_write_call_ops_v4,
1884                           sync, RPC_TASK_SOFTCONN);
1885         put_cred(ds_cred);
1886         return PNFS_ATTEMPTED;
1887
1888 out_failed:
1889         if (ff_layout_avoid_mds_available_ds(lseg))
1890                 return PNFS_TRY_AGAIN;
1891         trace_pnfs_mds_fallback_write_pagelist(hdr->inode,
1892                         hdr->args.offset, hdr->args.count,
1893                         IOMODE_RW, NFS_I(hdr->inode)->layout, lseg);
1894         return PNFS_NOT_ATTEMPTED;
1895 }
1896
1897 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1898 {
1899         return i;
1900 }
1901
1902 static struct nfs_fh *
1903 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1904 {
1905         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1906
1907         /* FIXME: Assume that there is only one NFS version available
1908          * for the DS.
1909          */
1910         return &flseg->mirror_array[i]->fh_versions[0];
1911 }
1912
1913 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1914 {
1915         struct pnfs_layout_segment *lseg = data->lseg;
1916         struct nfs4_pnfs_ds *ds;
1917         struct rpc_clnt *ds_clnt;
1918         struct nfs4_ff_layout_mirror *mirror;
1919         const struct cred *ds_cred;
1920         u32 idx;
1921         int vers, ret;
1922         struct nfs_fh *fh;
1923
1924         if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1925             test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1926                 goto out_err;
1927
1928         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1929         mirror = FF_LAYOUT_COMP(lseg, idx);
1930         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1931         if (!ds)
1932                 goto out_err;
1933
1934         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1935                                                    data->inode);
1936         if (IS_ERR(ds_clnt))
1937                 goto out_err;
1938
1939         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
1940         if (!ds_cred)
1941                 goto out_err;
1942
1943         vers = nfs4_ff_layout_ds_version(mirror);
1944
1945         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1946                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1947                 vers);
1948         data->commit_done_cb = ff_layout_commit_done_cb;
1949         data->cred = ds_cred;
1950         refcount_inc(&ds->ds_clp->cl_count);
1951         data->ds_clp = ds->ds_clp;
1952         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1953         if (fh)
1954                 data->args.fh = fh;
1955
1956         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1957                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1958                                                &ff_layout_commit_call_ops_v4,
1959                                    how, RPC_TASK_SOFTCONN);
1960         put_cred(ds_cred);
1961         return ret;
1962 out_err:
1963         pnfs_generic_prepare_to_resend_writes(data);
1964         pnfs_generic_commit_release(data);
1965         return -EAGAIN;
1966 }
1967
1968 static int
1969 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1970                            int how, struct nfs_commit_info *cinfo)
1971 {
1972         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1973                                             ff_layout_initiate_commit);
1974 }
1975
1976 static bool ff_layout_match_rw(const struct rpc_task *task,
1977                                const struct nfs_pgio_header *hdr,
1978                                const struct pnfs_layout_segment *lseg)
1979 {
1980         return hdr->lseg == lseg;
1981 }
1982
1983 static bool ff_layout_match_commit(const struct rpc_task *task,
1984                                    const struct nfs_commit_data *cdata,
1985                                    const struct pnfs_layout_segment *lseg)
1986 {
1987         return cdata->lseg == lseg;
1988 }
1989
1990 static bool ff_layout_match_io(const struct rpc_task *task, const void *data)
1991 {
1992         const struct rpc_call_ops *ops = task->tk_ops;
1993
1994         if (ops == &ff_layout_read_call_ops_v3 ||
1995             ops == &ff_layout_read_call_ops_v4 ||
1996             ops == &ff_layout_write_call_ops_v3 ||
1997             ops == &ff_layout_write_call_ops_v4)
1998                 return ff_layout_match_rw(task, task->tk_calldata, data);
1999         if (ops == &ff_layout_commit_call_ops_v3 ||
2000             ops == &ff_layout_commit_call_ops_v4)
2001                 return ff_layout_match_commit(task, task->tk_calldata, data);
2002         return false;
2003 }
2004
2005 static void ff_layout_cancel_io(struct pnfs_layout_segment *lseg)
2006 {
2007         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
2008         struct nfs4_ff_layout_mirror *mirror;
2009         struct nfs4_ff_layout_ds *mirror_ds;
2010         struct nfs4_pnfs_ds *ds;
2011         struct nfs_client *ds_clp;
2012         struct rpc_clnt *clnt;
2013         u32 idx;
2014
2015         for (idx = 0; idx < flseg->mirror_array_cnt; idx++) {
2016                 mirror = flseg->mirror_array[idx];
2017                 mirror_ds = mirror->mirror_ds;
2018                 if (!mirror_ds)
2019                         continue;
2020                 ds = mirror->mirror_ds->ds;
2021                 if (!ds)
2022                         continue;
2023                 ds_clp = ds->ds_clp;
2024                 if (!ds_clp)
2025                         continue;
2026                 clnt = ds_clp->cl_rpcclient;
2027                 if (!clnt)
2028                         continue;
2029                 if (!rpc_cancel_tasks(clnt, -EAGAIN, ff_layout_match_io, lseg))
2030                         continue;
2031                 rpc_clnt_disconnect(clnt);
2032         }
2033 }
2034
2035 static struct pnfs_ds_commit_info *
2036 ff_layout_get_ds_info(struct inode *inode)
2037 {
2038         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
2039
2040         if (layout == NULL)
2041                 return NULL;
2042
2043         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
2044 }
2045
2046 static void
2047 ff_layout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
2048                 struct pnfs_layout_segment *lseg)
2049 {
2050         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
2051         struct inode *inode = lseg->pls_layout->plh_inode;
2052         struct pnfs_commit_array *array, *new;
2053
2054         new = pnfs_alloc_commit_array(flseg->mirror_array_cnt,
2055                                       nfs_io_gfp_mask());
2056         if (new) {
2057                 spin_lock(&inode->i_lock);
2058                 array = pnfs_add_commit_array(fl_cinfo, new, lseg);
2059                 spin_unlock(&inode->i_lock);
2060                 if (array != new)
2061                         pnfs_free_commit_array(new);
2062         }
2063 }
2064
2065 static void
2066 ff_layout_release_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
2067                 struct inode *inode)
2068 {
2069         spin_lock(&inode->i_lock);
2070         pnfs_generic_ds_cinfo_destroy(fl_cinfo);
2071         spin_unlock(&inode->i_lock);
2072 }
2073
2074 static void
2075 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
2076 {
2077         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
2078                                                   id_node));
2079 }
2080
2081 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
2082                                   const struct nfs4_layoutreturn_args *args,
2083                                   const struct nfs4_flexfile_layoutreturn_args *ff_args)
2084 {
2085         __be32 *start;
2086
2087         start = xdr_reserve_space(xdr, 4);
2088         if (unlikely(!start))
2089                 return -E2BIG;
2090
2091         *start = cpu_to_be32(ff_args->num_errors);
2092         /* This assume we always return _ALL_ layouts */
2093         return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
2094 }
2095
2096 static void
2097 encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
2098 {
2099         WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
2100 }
2101
2102 static void
2103 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
2104                             const nfs4_stateid *stateid,
2105                             const struct nfs42_layoutstat_devinfo *devinfo)
2106 {
2107         __be32 *p;
2108
2109         p = xdr_reserve_space(xdr, 8 + 8);
2110         p = xdr_encode_hyper(p, devinfo->offset);
2111         p = xdr_encode_hyper(p, devinfo->length);
2112         encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
2113         p = xdr_reserve_space(xdr, 4*8);
2114         p = xdr_encode_hyper(p, devinfo->read_count);
2115         p = xdr_encode_hyper(p, devinfo->read_bytes);
2116         p = xdr_encode_hyper(p, devinfo->write_count);
2117         p = xdr_encode_hyper(p, devinfo->write_bytes);
2118         encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
2119 }
2120
2121 static void
2122 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
2123                             const nfs4_stateid *stateid,
2124                             const struct nfs42_layoutstat_devinfo *devinfo)
2125 {
2126         ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
2127         ff_layout_encode_ff_layoutupdate(xdr, devinfo,
2128                         devinfo->ld_private.data);
2129 }
2130
2131 /* report nothing for now */
2132 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
2133                 const struct nfs4_layoutreturn_args *args,
2134                 struct nfs4_flexfile_layoutreturn_args *ff_args)
2135 {
2136         __be32 *p;
2137         int i;
2138
2139         p = xdr_reserve_space(xdr, 4);
2140         *p = cpu_to_be32(ff_args->num_dev);
2141         for (i = 0; i < ff_args->num_dev; i++)
2142                 ff_layout_encode_ff_iostat(xdr,
2143                                 &args->layout->plh_stateid,
2144                                 &ff_args->devinfo[i]);
2145 }
2146
2147 static void
2148 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
2149                 unsigned int num_entries)
2150 {
2151         unsigned int i;
2152
2153         for (i = 0; i < num_entries; i++) {
2154                 if (!devinfo[i].ld_private.ops)
2155                         continue;
2156                 if (!devinfo[i].ld_private.ops->free)
2157                         continue;
2158                 devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2159         }
2160 }
2161
2162 static struct nfs4_deviceid_node *
2163 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2164                               struct pnfs_device *pdev, gfp_t gfp_flags)
2165 {
2166         struct nfs4_ff_layout_ds *dsaddr;
2167
2168         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2169         if (!dsaddr)
2170                 return NULL;
2171         return &dsaddr->id_node;
2172 }
2173
2174 static void
2175 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2176                 const void *voidargs,
2177                 const struct nfs4_xdr_opaque_data *ff_opaque)
2178 {
2179         const struct nfs4_layoutreturn_args *args = voidargs;
2180         struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2181         struct xdr_buf tmp_buf = {
2182                 .head = {
2183                         [0] = {
2184                                 .iov_base = page_address(ff_args->pages[0]),
2185                         },
2186                 },
2187                 .buflen = PAGE_SIZE,
2188         };
2189         struct xdr_stream tmp_xdr;
2190         __be32 *start;
2191
2192         dprintk("%s: Begin\n", __func__);
2193
2194         xdr_init_encode(&tmp_xdr, &tmp_buf, NULL, NULL);
2195
2196         ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2197         ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2198
2199         start = xdr_reserve_space(xdr, 4);
2200         *start = cpu_to_be32(tmp_buf.len);
2201         xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2202
2203         dprintk("%s: Return\n", __func__);
2204 }
2205
2206 static void
2207 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2208 {
2209         struct nfs4_flexfile_layoutreturn_args *ff_args;
2210
2211         if (!args->data)
2212                 return;
2213         ff_args = args->data;
2214         args->data = NULL;
2215
2216         ff_layout_free_ds_ioerr(&ff_args->errors);
2217         ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2218
2219         put_page(ff_args->pages[0]);
2220         kfree(ff_args);
2221 }
2222
2223 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2224         .encode = ff_layout_encode_layoutreturn,
2225         .free = ff_layout_free_layoutreturn,
2226 };
2227
2228 static int
2229 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2230 {
2231         struct nfs4_flexfile_layoutreturn_args *ff_args;
2232         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2233
2234         ff_args = kmalloc(sizeof(*ff_args), nfs_io_gfp_mask());
2235         if (!ff_args)
2236                 goto out_nomem;
2237         ff_args->pages[0] = alloc_page(nfs_io_gfp_mask());
2238         if (!ff_args->pages[0])
2239                 goto out_nomem_free;
2240
2241         INIT_LIST_HEAD(&ff_args->errors);
2242         ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2243                         &args->range, &ff_args->errors,
2244                         FF_LAYOUTRETURN_MAXERR);
2245
2246         spin_lock(&args->inode->i_lock);
2247         ff_args->num_dev = ff_layout_mirror_prepare_stats(
2248                 &ff_layout->generic_hdr, &ff_args->devinfo[0],
2249                 ARRAY_SIZE(ff_args->devinfo), NFS4_FF_OP_LAYOUTRETURN);
2250         spin_unlock(&args->inode->i_lock);
2251
2252         args->ld_private->ops = &layoutreturn_ops;
2253         args->ld_private->data = ff_args;
2254         return 0;
2255 out_nomem_free:
2256         kfree(ff_args);
2257 out_nomem:
2258         return -ENOMEM;
2259 }
2260
2261 #ifdef CONFIG_NFS_V4_2
2262 void
2263 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2264 {
2265         struct pnfs_layout_hdr *lo = lseg->pls_layout;
2266         struct nfs42_layout_error *errors;
2267         LIST_HEAD(head);
2268
2269         if (!nfs_server_capable(lo->plh_inode, NFS_CAP_LAYOUTERROR))
2270                 return;
2271         ff_layout_fetch_ds_ioerr(lo, &lseg->pls_range, &head, -1);
2272         if (list_empty(&head))
2273                 return;
2274
2275         errors = kmalloc_array(NFS42_LAYOUTERROR_MAX, sizeof(*errors),
2276                                nfs_io_gfp_mask());
2277         if (errors != NULL) {
2278                 const struct nfs4_ff_layout_ds_err *pos;
2279                 size_t n = 0;
2280
2281                 list_for_each_entry(pos, &head, list) {
2282                         errors[n].offset = pos->offset;
2283                         errors[n].length = pos->length;
2284                         nfs4_stateid_copy(&errors[n].stateid, &pos->stateid);
2285                         errors[n].errors[0].dev_id = pos->deviceid;
2286                         errors[n].errors[0].status = pos->status;
2287                         errors[n].errors[0].opnum = pos->opnum;
2288                         n++;
2289                         if (!list_is_last(&pos->list, &head) &&
2290                             n < NFS42_LAYOUTERROR_MAX)
2291                                 continue;
2292                         if (nfs42_proc_layouterror(lseg, errors, n) < 0)
2293                                 break;
2294                         n = 0;
2295                 }
2296                 kfree(errors);
2297         }
2298         ff_layout_free_ds_ioerr(&head);
2299 }
2300 #else
2301 void
2302 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2303 {
2304 }
2305 #endif
2306
2307 static int
2308 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2309 {
2310         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2311
2312         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2313 }
2314
2315 static size_t
2316 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2317                           const int buflen)
2318 {
2319         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2320         const struct in6_addr *addr = &sin6->sin6_addr;
2321
2322         /*
2323          * RFC 4291, Section 2.2.2
2324          *
2325          * Shorthanded ANY address
2326          */
2327         if (ipv6_addr_any(addr))
2328                 return snprintf(buf, buflen, "::");
2329
2330         /*
2331          * RFC 4291, Section 2.2.2
2332          *
2333          * Shorthanded loopback address
2334          */
2335         if (ipv6_addr_loopback(addr))
2336                 return snprintf(buf, buflen, "::1");
2337
2338         /*
2339          * RFC 4291, Section 2.2.3
2340          *
2341          * Special presentation address format for mapped v4
2342          * addresses.
2343          */
2344         if (ipv6_addr_v4mapped(addr))
2345                 return snprintf(buf, buflen, "::ffff:%pI4",
2346                                         &addr->s6_addr32[3]);
2347
2348         /*
2349          * RFC 4291, Section 2.2.1
2350          */
2351         return snprintf(buf, buflen, "%pI6c", addr);
2352 }
2353
2354 /* Derived from rpc_sockaddr2uaddr */
2355 static void
2356 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2357 {
2358         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2359         char portbuf[RPCBIND_MAXUADDRPLEN];
2360         char addrbuf[RPCBIND_MAXUADDRLEN];
2361         unsigned short port;
2362         int len, netid_len;
2363         __be32 *p;
2364
2365         switch (sap->sa_family) {
2366         case AF_INET:
2367                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2368                         return;
2369                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2370                 break;
2371         case AF_INET6:
2372                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2373                         return;
2374                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2375                 break;
2376         default:
2377                 WARN_ON_ONCE(1);
2378                 return;
2379         }
2380
2381         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2382         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2383
2384         netid_len = strlen(da->da_netid);
2385         p = xdr_reserve_space(xdr, 4 + netid_len);
2386         xdr_encode_opaque(p, da->da_netid, netid_len);
2387
2388         p = xdr_reserve_space(xdr, 4 + len);
2389         xdr_encode_opaque(p, addrbuf, len);
2390 }
2391
2392 static void
2393 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2394                          ktime_t t)
2395 {
2396         struct timespec64 ts;
2397         __be32 *p;
2398
2399         p = xdr_reserve_space(xdr, 12);
2400         ts = ktime_to_timespec64(t);
2401         p = xdr_encode_hyper(p, ts.tv_sec);
2402         *p++ = cpu_to_be32(ts.tv_nsec);
2403 }
2404
2405 static void
2406 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2407                             struct nfs4_ff_io_stat *stat)
2408 {
2409         __be32 *p;
2410
2411         p = xdr_reserve_space(xdr, 5 * 8);
2412         p = xdr_encode_hyper(p, stat->ops_requested);
2413         p = xdr_encode_hyper(p, stat->bytes_requested);
2414         p = xdr_encode_hyper(p, stat->ops_completed);
2415         p = xdr_encode_hyper(p, stat->bytes_completed);
2416         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2417         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2418         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2419 }
2420
2421 static void
2422 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2423                               const struct nfs42_layoutstat_devinfo *devinfo,
2424                               struct nfs4_ff_layout_mirror *mirror)
2425 {
2426         struct nfs4_pnfs_ds_addr *da;
2427         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2428         struct nfs_fh *fh = &mirror->fh_versions[0];
2429         __be32 *p;
2430
2431         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2432         dprintk("%s: DS %s: encoding address %s\n",
2433                 __func__, ds->ds_remotestr, da->da_remotestr);
2434         /* netaddr4 */
2435         ff_layout_encode_netaddr(xdr, da);
2436         /* nfs_fh4 */
2437         p = xdr_reserve_space(xdr, 4 + fh->size);
2438         xdr_encode_opaque(p, fh->data, fh->size);
2439         /* ff_io_latency4 read */
2440         spin_lock(&mirror->lock);
2441         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2442         /* ff_io_latency4 write */
2443         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2444         spin_unlock(&mirror->lock);
2445         /* nfstime4 */
2446         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2447         /* bool */
2448         p = xdr_reserve_space(xdr, 4);
2449         *p = cpu_to_be32(false);
2450 }
2451
2452 static void
2453 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2454                              const struct nfs4_xdr_opaque_data *opaque)
2455 {
2456         struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2457                         struct nfs42_layoutstat_devinfo, ld_private);
2458         __be32 *start;
2459
2460         /* layoutupdate length */
2461         start = xdr_reserve_space(xdr, 4);
2462         ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2463
2464         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2465 }
2466
2467 static void
2468 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2469 {
2470         struct nfs4_ff_layout_mirror *mirror = opaque->data;
2471
2472         ff_layout_put_mirror(mirror);
2473 }
2474
2475 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2476         .encode = ff_layout_encode_layoutstats,
2477         .free   = ff_layout_free_layoutstats,
2478 };
2479
2480 static int
2481 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2482                                struct nfs42_layoutstat_devinfo *devinfo,
2483                                int dev_limit, enum nfs4_ff_op_type type)
2484 {
2485         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2486         struct nfs4_ff_layout_mirror *mirror;
2487         struct nfs4_deviceid_node *dev;
2488         int i = 0;
2489
2490         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2491                 if (i >= dev_limit)
2492                         break;
2493                 if (IS_ERR_OR_NULL(mirror->mirror_ds))
2494                         continue;
2495                 if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL,
2496                                         &mirror->flags) &&
2497                     type != NFS4_FF_OP_LAYOUTRETURN)
2498                         continue;
2499                 /* mirror refcount put in cleanup_layoutstats */
2500                 if (!refcount_inc_not_zero(&mirror->ref))
2501                         continue;
2502                 dev = &mirror->mirror_ds->id_node;
2503                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2504                 devinfo->offset = 0;
2505                 devinfo->length = NFS4_MAX_UINT64;
2506                 spin_lock(&mirror->lock);
2507                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2508                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2509                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2510                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2511                 spin_unlock(&mirror->lock);
2512                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2513                 devinfo->ld_private.ops = &layoutstat_ops;
2514                 devinfo->ld_private.data = mirror;
2515
2516                 devinfo++;
2517                 i++;
2518         }
2519         return i;
2520 }
2521
2522 static int
2523 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2524 {
2525         struct nfs4_flexfile_layout *ff_layout;
2526         const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2527
2528         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2529         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo),
2530                                       nfs_io_gfp_mask());
2531         if (!args->devinfo)
2532                 return -ENOMEM;
2533
2534         spin_lock(&args->inode->i_lock);
2535         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2536         args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2537                                                        &args->devinfo[0],
2538                                                        dev_count,
2539                                                        NFS4_FF_OP_LAYOUTSTATS);
2540         spin_unlock(&args->inode->i_lock);
2541         if (!args->num_dev) {
2542                 kfree(args->devinfo);
2543                 args->devinfo = NULL;
2544                 return -ENOENT;
2545         }
2546
2547         return 0;
2548 }
2549
2550 static int
2551 ff_layout_set_layoutdriver(struct nfs_server *server,
2552                 const struct nfs_fh *dummy)
2553 {
2554 #if IS_ENABLED(CONFIG_NFS_V4_2)
2555         server->caps |= NFS_CAP_LAYOUTSTATS;
2556 #endif
2557         return 0;
2558 }
2559
2560 static const struct pnfs_commit_ops ff_layout_commit_ops = {
2561         .setup_ds_info          = ff_layout_setup_ds_info,
2562         .release_ds_info        = ff_layout_release_ds_info,
2563         .mark_request_commit    = pnfs_layout_mark_request_commit,
2564         .clear_request_commit   = pnfs_generic_clear_request_commit,
2565         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2566         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2567         .commit_pagelist        = ff_layout_commit_pagelist,
2568 };
2569
2570 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2571         .id                     = LAYOUT_FLEX_FILES,
2572         .name                   = "LAYOUT_FLEX_FILES",
2573         .owner                  = THIS_MODULE,
2574         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
2575         .max_layoutget_response = 4096, /* 1 page or so... */
2576         .set_layoutdriver       = ff_layout_set_layoutdriver,
2577         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2578         .free_layout_hdr        = ff_layout_free_layout_hdr,
2579         .alloc_lseg             = ff_layout_alloc_lseg,
2580         .free_lseg              = ff_layout_free_lseg,
2581         .add_lseg               = ff_layout_add_lseg,
2582         .pg_read_ops            = &ff_layout_pg_read_ops,
2583         .pg_write_ops           = &ff_layout_pg_write_ops,
2584         .get_ds_info            = ff_layout_get_ds_info,
2585         .free_deviceid_node     = ff_layout_free_deviceid_node,
2586         .read_pagelist          = ff_layout_read_pagelist,
2587         .write_pagelist         = ff_layout_write_pagelist,
2588         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2589         .prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2590         .sync                   = pnfs_nfs_generic_sync,
2591         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2592         .cancel_io              = ff_layout_cancel_io,
2593 };
2594
2595 static int __init nfs4flexfilelayout_init(void)
2596 {
2597         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2598                __func__);
2599         return pnfs_register_layoutdriver(&flexfilelayout_type);
2600 }
2601
2602 static void __exit nfs4flexfilelayout_exit(void)
2603 {
2604         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2605                __func__);
2606         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2607 }
2608
2609 MODULE_ALIAS("nfs-layouttype4-4");
2610
2611 MODULE_LICENSE("GPL");
2612 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2613
2614 module_init(nfs4flexfilelayout_init);
2615 module_exit(nfs4flexfilelayout_exit);
2616
2617 module_param(io_maxretrans, ushort, 0644);
2618 MODULE_PARM_DESC(io_maxretrans, "The  number of times the NFSv4.1 client "
2619                         "retries an I/O request before returning an error. ");