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 <bergwolf@primarydata.com>
   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 static unsigned short io_maxretrans;
  34
  35 static const struct pnfs_commit_ops ff_layout_commit_ops;
  36 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
  37                 struct nfs_pgio_header *hdr);
  38 static int ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
  39                                struct nfs42_layoutstat_devinfo *devinfo,
  40                                int dev_limit);
  41 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
  42                               const struct nfs42_layoutstat_devinfo *devinfo,
  43                               struct nfs4_ff_layout_mirror *mirror);
  44
  45 static struct pnfs_layout_hdr *
  46 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  47 {
  48         struct nfs4_flexfile_layout *ffl;
  49
  50         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  51         if (ffl) {
  52                 pnfs_init_ds_commit_info(&ffl->commit_info);
  53                 INIT_LIST_HEAD(&ffl->error_list);
  54                 INIT_LIST_HEAD(&ffl->mirrors);
  55                 ffl->last_report_time = ktime_get();
  56                 ffl->commit_info.ops = &ff_layout_commit_ops;
  57                 return &ffl->generic_hdr;
  58         } else
  59                 return NULL;
  60 }
  61
  62 static void
  63 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  64 {
  65         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(lo);
  66         struct nfs4_ff_layout_ds_err *err, *n;
  67
  68         list_for_each_entry_safe(err, n, &ffl->error_list, list) {
  69                 list_del(&err->list);
  70                 kfree(err);
  71         }
  72         kfree_rcu(ffl, generic_hdr.plh_rcu);
  73 }
  74
  75 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  76 {
  77         __be32 *p;
  78
  79         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  80         if (unlikely(p == NULL))
  81                 return -ENOBUFS;
  82         stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  83         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  84         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  85                 p[0], p[1], p[2], p[3]);
  86         return 0;
  87 }
  88
  89 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  90 {
  91         __be32 *p;
  92
  93         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  94         if (unlikely(!p))
  95                 return -ENOBUFS;
  96         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  97         nfs4_print_deviceid(devid);
  98         return 0;
  99 }
 100
 101 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
 102 {
 103         __be32 *p;
 104
 105         p = xdr_inline_decode(xdr, 4);
 106         if (unlikely(!p))
 107                 return -ENOBUFS;
 108         fh->size = be32_to_cpup(p++);
 109         if (fh->size > NFS_MAXFHSIZE) {
 110                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
 111                        fh->size);
 112                 return -EOVERFLOW;
 113         }
 114         /* fh.data */
 115         p = xdr_inline_decode(xdr, fh->size);
 116         if (unlikely(!p))
 117                 return -ENOBUFS;
 118         memcpy(&fh->data, p, fh->size);
 119         dprintk("%s: fh len %d\n", __func__, fh->size);
 120
 121         return 0;
 122 }
 123
 124 /*
 125  * Currently only stringified uids and gids are accepted.
 126  * I.e., kerberos is not supported to the DSes, so no pricipals.
 127  *
 128  * That means that one common function will suffice, but when
 129  * principals are added, this should be split to accomodate
 130  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 131  */
 132 static int
 133 decode_name(struct xdr_stream *xdr, u32 *id)
 134 {
 135         __be32 *p;
 136         int len;
 137
 138         /* opaque_length(4)*/
 139         p = xdr_inline_decode(xdr, 4);
 140         if (unlikely(!p))
 141                 return -ENOBUFS;
 142         len = be32_to_cpup(p++);
 143         if (len < 0)
 144                 return -EINVAL;
 145
 146         dprintk("%s: len %u\n", __func__, len);
 147
 148         /* opaque body */
 149         p = xdr_inline_decode(xdr, len);
 150         if (unlikely(!p))
 151                 return -ENOBUFS;
 152
 153         if (!nfs_map_string_to_numeric((char *)p, len, id))
 154                 return -EINVAL;
 155
 156         return 0;
 157 }
 158
 159 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 160                 const struct nfs4_ff_layout_mirror *m2)
 161 {
 162         int i, j;
 163
 164         if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 165                 return false;
 166         for (i = 0; i < m1->fh_versions_cnt; i++) {
 167                 bool found_fh = false;
 168                 for (j = 0; j < m2->fh_versions_cnt; j++) {
 169                         if (nfs_compare_fh(&m1->fh_versions[i],
 170                                         &m2->fh_versions[j]) == 0) {
 171                                 found_fh = true;
 172                                 break;
 173                         }
 174                 }
 175                 if (!found_fh)
 176                         return false;
 177         }
 178         return true;
 179 }
 180
 181 static struct nfs4_ff_layout_mirror *
 182 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 183                 struct nfs4_ff_layout_mirror *mirror)
 184 {
 185         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 186         struct nfs4_ff_layout_mirror *pos;
 187         struct inode *inode = lo->plh_inode;
 188
 189         spin_lock(&inode->i_lock);
 190         list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 191                 if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
 192                         continue;
 193                 if (!ff_mirror_match_fh(mirror, pos))
 194                         continue;
 195                 if (refcount_inc_not_zero(&pos->ref)) {
 196                         spin_unlock(&inode->i_lock);
 197                         return pos;
 198                 }
 199         }
 200         list_add(&mirror->mirrors, &ff_layout->mirrors);
 201         mirror->layout = lo;
 202         spin_unlock(&inode->i_lock);
 203         return mirror;
 204 }
 205
 206 static void
 207 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 208 {
 209         struct inode *inode;
 210         if (mirror->layout == NULL)
 211                 return;
 212         inode = mirror->layout->plh_inode;
 213         spin_lock(&inode->i_lock);
 214         list_del(&mirror->mirrors);
 215         spin_unlock(&inode->i_lock);
 216         mirror->layout = NULL;
 217 }
 218
 219 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 220 {
 221         struct nfs4_ff_layout_mirror *mirror;
 222
 223         mirror = kzalloc(sizeof(*mirror), gfp_flags);
 224         if (mirror != NULL) {
 225                 spin_lock_init(&mirror->lock);
 226                 refcount_set(&mirror->ref, 1);
 227                 INIT_LIST_HEAD(&mirror->mirrors);
 228         }
 229         return mirror;
 230 }
 231
 232 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 233 {
 234         const struct cred       *cred;
 235
 236         ff_layout_remove_mirror(mirror);
 237         kfree(mirror->fh_versions);
 238         cred = rcu_access_pointer(mirror->ro_cred);
 239         put_cred(cred);
 240         cred = rcu_access_pointer(mirror->rw_cred);
 241         put_cred(cred);
 242         nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 243         kfree(mirror);
 244 }
 245
 246 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 247 {
 248         if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
 249                 ff_layout_free_mirror(mirror);
 250 }
 251
 252 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 253 {
 254         u32 i;
 255
 256         for (i = 0; i < fls->mirror_array_cnt; i++)
 257                 ff_layout_put_mirror(fls->mirror_array[i]);
 258 }
 259
 260 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 261 {
 262         if (fls) {
 263                 ff_layout_free_mirror_array(fls);
 264                 kfree(fls);
 265         }
 266 }
 267
 268 static bool
 269 ff_lseg_match_mirrors(struct pnfs_layout_segment *l1,
 270                 struct pnfs_layout_segment *l2)
 271 {
 272         const struct nfs4_ff_layout_segment *fl1 = FF_LAYOUT_LSEG(l1);
 273         const struct nfs4_ff_layout_segment *fl2 = FF_LAYOUT_LSEG(l1);
 274         u32 i;
 275
 276         if (fl1->mirror_array_cnt != fl2->mirror_array_cnt)
 277                 return false;
 278         for (i = 0; i < fl1->mirror_array_cnt; i++) {
 279                 if (fl1->mirror_array[i] != fl2->mirror_array[i])
 280                         return false;
 281         }
 282         return true;
 283 }
 284
 285 static bool
 286 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 287                 const struct pnfs_layout_range *l2)
 288 {
 289         u64 end1, end2;
 290
 291         if (l1->iomode != l2->iomode)
 292                 return l1->iomode != IOMODE_READ;
 293         end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 294         end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 295         if (end1 < l2->offset)
 296                 return false;
 297         if (end2 < l1->offset)
 298                 return true;
 299         return l2->offset <= l1->offset;
 300 }
 301
 302 static bool
 303 ff_lseg_merge(struct pnfs_layout_segment *new,
 304                 struct pnfs_layout_segment *old)
 305 {
 306         u64 new_end, old_end;
 307
 308         if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 309                 return false;
 310         if (new->pls_range.iomode != old->pls_range.iomode)
 311                 return false;
 312         old_end = pnfs_calc_offset_end(old->pls_range.offset,
 313                         old->pls_range.length);
 314         if (old_end < new->pls_range.offset)
 315                 return false;
 316         new_end = pnfs_calc_offset_end(new->pls_range.offset,
 317                         new->pls_range.length);
 318         if (new_end < old->pls_range.offset)
 319                 return false;
 320         if (!ff_lseg_match_mirrors(new, old))
 321                 return false;
 322
 323         /* Mergeable: copy info from 'old' to 'new' */
 324         if (new_end < old_end)
 325                 new_end = old_end;
 326         if (new->pls_range.offset < old->pls_range.offset)
 327                 new->pls_range.offset = old->pls_range.offset;
 328         new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 329                         new_end);
 330         if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 331                 set_bit(NFS_LSEG_ROC, &new->pls_flags);
 332         return true;
 333 }
 334
 335 static void
 336 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 337                 struct pnfs_layout_segment *lseg,
 338                 struct list_head *free_me)
 339 {
 340         pnfs_generic_layout_insert_lseg(lo, lseg,
 341                         ff_lseg_range_is_after,
 342                         ff_lseg_merge,
 343                         free_me);
 344 }
 345
 346 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 347 {
 348         int i, j;
 349
 350         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 351                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 352                         if (fls->mirror_array[i]->efficiency <
 353                             fls->mirror_array[j]->efficiency)
 354                                 swap(fls->mirror_array[i],
 355                                      fls->mirror_array[j]);
 356         }
 357 }
 358
 359 static struct pnfs_layout_segment *
 360 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 361                      struct nfs4_layoutget_res *lgr,
 362                      gfp_t gfp_flags)
 363 {
 364         struct pnfs_layout_segment *ret;
 365         struct nfs4_ff_layout_segment *fls = NULL;
 366         struct xdr_stream stream;
 367         struct xdr_buf buf;
 368         struct page *scratch;
 369         u64 stripe_unit;
 370         u32 mirror_array_cnt;
 371         __be32 *p;
 372         int i, rc;
 373
 374         dprintk("--> %s\n", __func__);
 375         scratch = alloc_page(gfp_flags);
 376         if (!scratch)
 377                 return ERR_PTR(-ENOMEM);
 378
 379         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 380                               lgr->layoutp->len);
 381         xdr_set_scratch_page(&stream, scratch);
 382
 383         /* stripe unit and mirror_array_cnt */
 384         rc = -EIO;
 385         p = xdr_inline_decode(&stream, 8 + 4);
 386         if (!p)
 387                 goto out_err_free;
 388
 389         p = xdr_decode_hyper(p, &stripe_unit);
 390         mirror_array_cnt = be32_to_cpup(p++);
 391         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 392                 stripe_unit, mirror_array_cnt);
 393
 394         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 395             mirror_array_cnt == 0)
 396                 goto out_err_free;
 397
 398         rc = -ENOMEM;
 399         fls = kzalloc(struct_size(fls, mirror_array, mirror_array_cnt),
 400                         gfp_flags);
 401         if (!fls)
 402                 goto out_err_free;
 403
 404         fls->mirror_array_cnt = mirror_array_cnt;
 405         fls->stripe_unit = stripe_unit;
 406
 407         for (i = 0; i < fls->mirror_array_cnt; i++) {
 408                 struct nfs4_ff_layout_mirror *mirror;
 409                 struct cred *kcred;
 410                 const struct cred __rcu *cred;
 411                 kuid_t uid;
 412                 kgid_t gid;
 413                 u32 ds_count, fh_count, id;
 414                 int j;
 415
 416                 rc = -EIO;
 417                 p = xdr_inline_decode(&stream, 4);
 418                 if (!p)
 419                         goto out_err_free;
 420                 ds_count = be32_to_cpup(p);
 421
 422                 /* FIXME: allow for striping? */
 423                 if (ds_count != 1)
 424                         goto out_err_free;
 425
 426                 fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 427                 if (fls->mirror_array[i] == NULL) {
 428                         rc = -ENOMEM;
 429                         goto out_err_free;
 430                 }
 431
 432                 fls->mirror_array[i]->ds_count = ds_count;
 433
 434                 /* deviceid */
 435                 rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
 436                 if (rc)
 437                         goto out_err_free;
 438
 439                 /* efficiency */
 440                 rc = -EIO;
 441                 p = xdr_inline_decode(&stream, 4);
 442                 if (!p)
 443                         goto out_err_free;
 444                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 445
 446                 /* stateid */
 447                 rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 448                 if (rc)
 449                         goto out_err_free;
 450
 451                 /* fh */
 452                 rc = -EIO;
 453                 p = xdr_inline_decode(&stream, 4);
 454                 if (!p)
 455                         goto out_err_free;
 456                 fh_count = be32_to_cpup(p);
 457
 458                 fls->mirror_array[i]->fh_versions =
 459                         kcalloc(fh_count, sizeof(struct nfs_fh),
 460                                 gfp_flags);
 461                 if (fls->mirror_array[i]->fh_versions == NULL) {
 462                         rc = -ENOMEM;
 463                         goto out_err_free;
 464                 }
 465
 466                 for (j = 0; j < fh_count; j++) {
 467                         rc = decode_nfs_fh(&stream,
 468                                            &fls->mirror_array[i]->fh_versions[j]);
 469                         if (rc)
 470                                 goto out_err_free;
 471                 }
 472
 473                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 474
 475                 /* user */
 476                 rc = decode_name(&stream, &id);
 477                 if (rc)
 478                         goto out_err_free;
 479
 480                 uid = make_kuid(&init_user_ns, id);
 481
 482                 /* group */
 483                 rc = decode_name(&stream, &id);
 484                 if (rc)
 485                         goto out_err_free;
 486
 487                 gid = make_kgid(&init_user_ns, id);
 488
 489                 if (gfp_flags & __GFP_FS)
 490                         kcred = prepare_kernel_cred(NULL);
 491                 else {
 492                         unsigned int nofs_flags = memalloc_nofs_save();
 493                         kcred = prepare_kernel_cred(NULL);
 494                         memalloc_nofs_restore(nofs_flags);
 495                 }
 496                 rc = -ENOMEM;
 497                 if (!kcred)
 498                         goto out_err_free;
 499                 kcred->fsuid = uid;
 500                 kcred->fsgid = gid;
 501                 cred = RCU_INITIALIZER(kcred);
 502
 503                 if (lgr->range.iomode == IOMODE_READ)
 504                         rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 505                 else
 506                         rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 507
 508                 mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 509                 if (mirror != fls->mirror_array[i]) {
 510                         /* swap cred ptrs so free_mirror will clean up old */
 511                         if (lgr->range.iomode == IOMODE_READ) {
 512                                 cred = xchg(&mirror->ro_cred, cred);
 513                                 rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 514                         } else {
 515                                 cred = xchg(&mirror->rw_cred, cred);
 516                                 rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 517                         }
 518                         ff_layout_free_mirror(fls->mirror_array[i]);
 519                         fls->mirror_array[i] = mirror;
 520                 }
 521
 522                 dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 523                         lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 524                         from_kuid(&init_user_ns, uid),
 525                         from_kgid(&init_user_ns, gid));
 526         }
 527
 528         p = xdr_inline_decode(&stream, 4);
 529         if (!p)
 530                 goto out_sort_mirrors;
 531         fls->flags = be32_to_cpup(p);
 532
 533         p = xdr_inline_decode(&stream, 4);
 534         if (!p)
 535                 goto out_sort_mirrors;
 536         for (i=0; i < fls->mirror_array_cnt; i++)
 537                 fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 538
 539 out_sort_mirrors:
 540         ff_layout_sort_mirrors(fls);
 541         ret = &fls->generic_hdr;
 542         dprintk("<-- %s (success)\n", __func__);
 543 out_free_page:
 544         __free_page(scratch);
 545         return ret;
 546 out_err_free:
 547         _ff_layout_free_lseg(fls);
 548         ret = ERR_PTR(rc);
 549         dprintk("<-- %s (%d)\n", __func__, rc);
 550         goto out_free_page;
 551 }
 552
 553 static void
 554 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 555 {
 556         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 557
 558         dprintk("--> %s\n", __func__);
 559
 560         if (lseg->pls_range.iomode == IOMODE_RW) {
 561                 struct nfs4_flexfile_layout *ffl;
 562                 struct inode *inode;
 563
 564                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 565                 inode = ffl->generic_hdr.plh_inode;
 566                 spin_lock(&inode->i_lock);
 567                 pnfs_generic_ds_cinfo_release_lseg(&ffl->commit_info, lseg);
 568                 spin_unlock(&inode->i_lock);
 569         }
 570         _ff_layout_free_lseg(fls);
 571 }
 572
 573 static void
 574 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 575 {
 576         /* first IO request? */
 577         if (atomic_inc_return(&timer->n_ops) == 1) {
 578                 timer->start_time = now;
 579         }
 580 }
 581
 582 static ktime_t
 583 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 584 {
 585         ktime_t start;
 586
 587         if (atomic_dec_return(&timer->n_ops) < 0)
 588                 WARN_ON_ONCE(1);
 589
 590         start = timer->start_time;
 591         timer->start_time = now;
 592         return ktime_sub(now, start);
 593 }
 594
 595 static bool
 596 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 597                             struct nfs4_ff_layoutstat *layoutstat,
 598                             ktime_t now)
 599 {
 600         s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 601         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 602
 603         nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 604         if (!mirror->start_time)
 605                 mirror->start_time = now;
 606         if (mirror->report_interval != 0)
 607                 report_interval = (s64)mirror->report_interval * 1000LL;
 608         else if (layoutstats_timer != 0)
 609                 report_interval = (s64)layoutstats_timer * 1000LL;
 610         if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 611                         report_interval) {
 612                 ffl->last_report_time = now;
 613                 return true;
 614         }
 615
 616         return false;
 617 }
 618
 619 static void
 620 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 621                 __u64 requested)
 622 {
 623         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 624
 625         iostat->ops_requested++;
 626         iostat->bytes_requested += requested;
 627 }
 628
 629 static void
 630 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 631                 __u64 requested,
 632                 __u64 completed,
 633                 ktime_t time_completed,
 634                 ktime_t time_started)
 635 {
 636         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 637         ktime_t completion_time = ktime_sub(time_completed, time_started);
 638         ktime_t timer;
 639
 640         iostat->ops_completed++;
 641         iostat->bytes_completed += completed;
 642         iostat->bytes_not_delivered += requested - completed;
 643
 644         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 645         iostat->total_busy_time =
 646                         ktime_add(iostat->total_busy_time, timer);
 647         iostat->aggregate_completion_time =
 648                         ktime_add(iostat->aggregate_completion_time,
 649                                         completion_time);
 650 }
 651
 652 static void
 653 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 654                 struct nfs4_ff_layout_mirror *mirror,
 655                 __u64 requested, ktime_t now)
 656 {
 657         bool report;
 658
 659         spin_lock(&mirror->lock);
 660         report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 661         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 662         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 663         spin_unlock(&mirror->lock);
 664
 665         if (report)
 666                 pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
 667 }
 668
 669 static void
 670 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 671                 struct nfs4_ff_layout_mirror *mirror,
 672                 __u64 requested,
 673                 __u64 completed)
 674 {
 675         spin_lock(&mirror->lock);
 676         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 677                         requested, completed,
 678                         ktime_get(), task->tk_start);
 679         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 680         spin_unlock(&mirror->lock);
 681 }
 682
 683 static void
 684 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 685                 struct nfs4_ff_layout_mirror *mirror,
 686                 __u64 requested, ktime_t now)
 687 {
 688         bool report;
 689
 690         spin_lock(&mirror->lock);
 691         report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 692         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 693         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 694         spin_unlock(&mirror->lock);
 695
 696         if (report)
 697                 pnfs_report_layoutstat(inode, nfs_io_gfp_mask());
 698 }
 699
 700 static void
 701 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 702                 struct nfs4_ff_layout_mirror *mirror,
 703                 __u64 requested,
 704                 __u64 completed,
 705                 enum nfs3_stable_how committed)
 706 {
 707         if (committed == NFS_UNSTABLE)
 708                 requested = completed = 0;
 709
 710         spin_lock(&mirror->lock);
 711         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 712                         requested, completed, ktime_get(), task->tk_start);
 713         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 714         spin_unlock(&mirror->lock);
 715 }
 716
 717 static void
 718 ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, u32 idx)
 719 {
 720         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 721
 722         if (devid)
 723                 nfs4_mark_deviceid_unavailable(devid);
 724 }
 725
 726 static void
 727 ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, u32 idx)
 728 {
 729         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 730
 731         if (devid)
 732                 nfs4_mark_deviceid_available(devid);
 733 }
 734
 735 static struct nfs4_pnfs_ds *
 736 ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 737                              u32 start_idx, u32 *best_idx,
 738                              bool check_device)
 739 {
 740         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 741         struct nfs4_ff_layout_mirror *mirror;
 742         struct nfs4_pnfs_ds *ds;
 743         u32 idx;
 744
 745         /* mirrors are initially sorted by efficiency */
 746         for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 747                 mirror = FF_LAYOUT_COMP(lseg, idx);
 748                 ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
 749                 if (!ds)
 750                         continue;
 751
 752                 if (check_device &&
 753                     nfs4_test_deviceid_unavailable(&mirror->mirror_ds->id_node))
 754                         continue;
 755
 756                 *best_idx = idx;
 757                 return ds;
 758         }
 759
 760         return NULL;
 761 }
 762
 763 static struct nfs4_pnfs_ds *
 764 ff_layout_choose_any_ds_for_read(struct pnfs_layout_segment *lseg,
 765                                  u32 start_idx, u32 *best_idx)
 766 {
 767         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, false);
 768 }
 769
 770 static struct nfs4_pnfs_ds *
 771 ff_layout_choose_valid_ds_for_read(struct pnfs_layout_segment *lseg,
 772                                    u32 start_idx, u32 *best_idx)
 773 {
 774         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, true);
 775 }
 776
 777 static struct nfs4_pnfs_ds *
 778 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 779                                   u32 start_idx, u32 *best_idx)
 780 {
 781         struct nfs4_pnfs_ds *ds;
 782
 783         ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx);
 784         if (ds)
 785                 return ds;
 786         return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx);
 787 }
 788
 789 static struct nfs4_pnfs_ds *
 790 ff_layout_get_ds_for_read(struct nfs_pageio_descriptor *pgio,
 791                           u32 *best_idx)
 792 {
 793         struct pnfs_layout_segment *lseg = pgio->pg_lseg;
 794         struct nfs4_pnfs_ds *ds;
 795
 796         ds = ff_layout_choose_best_ds_for_read(lseg, pgio->pg_mirror_idx,
 797                                                best_idx);
 798         if (ds || !pgio->pg_mirror_idx)
 799                 return ds;
 800         return ff_layout_choose_best_ds_for_read(lseg, 0, best_idx);
 801 }
 802
 803 static void
 804 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 805                       struct nfs_page *req,
 806                       bool strict_iomode)
 807 {
 808         pnfs_put_lseg(pgio->pg_lseg);
 809         pgio->pg_lseg =
 810                 pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
 811                                    req_offset(req), req->wb_bytes, IOMODE_READ,
 812                                    strict_iomode, nfs_io_gfp_mask());
 813         if (IS_ERR(pgio->pg_lseg)) {
 814                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 815                 pgio->pg_lseg = NULL;
 816         }
 817 }
 818
 819 static void
 820 ff_layout_pg_check_layout(struct nfs_pageio_descriptor *pgio,
 821                           struct nfs_page *req)
 822 {
 823         pnfs_generic_pg_check_layout(pgio);
 824         pnfs_generic_pg_check_range(pgio, req);
 825 }
 826
 827 static void
 828 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 829                         struct nfs_page *req)
 830 {
 831         struct nfs_pgio_mirror *pgm;
 832         struct nfs4_ff_layout_mirror *mirror;
 833         struct nfs4_pnfs_ds *ds;
 834         u32 ds_idx;
 835
 836 retry:
 837         ff_layout_pg_check_layout(pgio, req);
 838         /* Use full layout for now */
 839         if (!pgio->pg_lseg) {
 840                 ff_layout_pg_get_read(pgio, req, false);
 841                 if (!pgio->pg_lseg)
 842                         goto out_nolseg;
 843         }
 844         if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 845                 ff_layout_pg_get_read(pgio, req, true);
 846                 if (!pgio->pg_lseg)
 847                         goto out_nolseg;
 848         }
 849
 850         ds = ff_layout_get_ds_for_read(pgio, &ds_idx);
 851         if (!ds) {
 852                 if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 853                         goto out_mds;
 854                 pnfs_generic_pg_cleanup(pgio);
 855                 /* Sleep for 1 second before retrying */
 856                 ssleep(1);
 857                 goto retry;
 858         }
 859
 860         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 861         pgm = &pgio->pg_mirrors[0];
 862         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 863
 864         pgio->pg_mirror_idx = ds_idx;
 865
 866         if (NFS_SERVER(pgio->pg_inode)->flags &
 867                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 868                 pgio->pg_maxretrans = io_maxretrans;
 869         return;
 870 out_nolseg:
 871         if (pgio->pg_error < 0)
 872                 return;
 873 out_mds:
 874         trace_pnfs_mds_fallback_pg_init_read(pgio->pg_inode,
 875                         0, NFS4_MAX_UINT64, IOMODE_READ,
 876                         NFS_I(pgio->pg_inode)->layout,
 877                         pgio->pg_lseg);
 878         pgio->pg_maxretrans = 0;
 879         nfs_pageio_reset_read_mds(pgio);
 880 }
 881
 882 static void
 883 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 884                         struct nfs_page *req)
 885 {
 886         struct nfs4_ff_layout_mirror *mirror;
 887         struct nfs_pgio_mirror *pgm;
 888         struct nfs4_pnfs_ds *ds;
 889         u32 i;
 890
 891 retry:
 892         ff_layout_pg_check_layout(pgio, req);
 893         if (!pgio->pg_lseg) {
 894                 pgio->pg_lseg =
 895                         pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
 896                                            req_offset(req), req->wb_bytes,
 897                                            IOMODE_RW, false, nfs_io_gfp_mask());
 898                 if (IS_ERR(pgio->pg_lseg)) {
 899                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 900                         pgio->pg_lseg = NULL;
 901                         return;
 902                 }
 903         }
 904         /* If no lseg, fall back to write through mds */
 905         if (pgio->pg_lseg == NULL)
 906                 goto out_mds;
 907
 908         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 909         if (pgio->pg_mirror_count != FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg))
 910                 goto out_eagain;
 911
 912         for (i = 0; i < pgio->pg_mirror_count; i++) {
 913                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 914                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
 915                 if (!ds) {
 916                         if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 917                                 goto out_mds;
 918                         pnfs_generic_pg_cleanup(pgio);
 919                         /* Sleep for 1 second before retrying */
 920                         ssleep(1);
 921                         goto retry;
 922                 }
 923                 pgm = &pgio->pg_mirrors[i];
 924                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 925         }
 926
 927         if (NFS_SERVER(pgio->pg_inode)->flags &
 928                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 929                 pgio->pg_maxretrans = io_maxretrans;
 930         return;
 931 out_eagain:
 932         pnfs_generic_pg_cleanup(pgio);
 933         pgio->pg_error = -EAGAIN;
 934         return;
 935 out_mds:
 936         trace_pnfs_mds_fallback_pg_init_write(pgio->pg_inode,
 937                         0, NFS4_MAX_UINT64, IOMODE_RW,
 938                         NFS_I(pgio->pg_inode)->layout,
 939                         pgio->pg_lseg);
 940         pgio->pg_maxretrans = 0;
 941         nfs_pageio_reset_write_mds(pgio);
 942         pgio->pg_error = -EAGAIN;
 943 }
 944
 945 static unsigned int
 946 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 947                                     struct nfs_page *req)
 948 {
 949         if (!pgio->pg_lseg) {
 950                 pgio->pg_lseg =
 951                         pnfs_update_layout(pgio->pg_inode, nfs_req_openctx(req),
 952                                            req_offset(req), req->wb_bytes,
 953                                            IOMODE_RW, false, nfs_io_gfp_mask());
 954                 if (IS_ERR(pgio->pg_lseg)) {
 955                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 956                         pgio->pg_lseg = NULL;
 957                         goto out;
 958                 }
 959         }
 960         if (pgio->pg_lseg)
 961                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 962
 963         trace_pnfs_mds_fallback_pg_get_mirror_count(pgio->pg_inode,
 964                         0, NFS4_MAX_UINT64, IOMODE_RW,
 965                         NFS_I(pgio->pg_inode)->layout,
 966                         pgio->pg_lseg);
 967         /* no lseg means that pnfs is not in use, so no mirroring here */
 968         nfs_pageio_reset_write_mds(pgio);
 969 out:
 970         return 1;
 971 }
 972
 973 static u32
 974 ff_layout_pg_set_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 975 {
 976         u32 old = desc->pg_mirror_idx;
 977
 978         desc->pg_mirror_idx = idx;
 979         return old;
 980 }
 981
 982 static struct nfs_pgio_mirror *
 983 ff_layout_pg_get_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 984 {
 985         return &desc->pg_mirrors[idx];
 986 }
 987
 988 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 989         .pg_init = ff_layout_pg_init_read,
 990         .pg_test = pnfs_generic_pg_test,
 991         .pg_doio = pnfs_generic_pg_readpages,
 992         .pg_cleanup = pnfs_generic_pg_cleanup,
 993 };
 994
 995 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
 996         .pg_init = ff_layout_pg_init_write,
 997         .pg_test = pnfs_generic_pg_test,
 998         .pg_doio = pnfs_generic_pg_writepages,
 999         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1000         .pg_cleanup = pnfs_generic_pg_cleanup,
1001         .pg_get_mirror = ff_layout_pg_get_mirror_write,
1002         .pg_set_mirror = ff_layout_pg_set_mirror_write,
1003 };
1004
1005 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1006 {
1007         struct rpc_task *task = &hdr->task;
1008
1009         pnfs_layoutcommit_inode(hdr->inode, false);
1010
1011         if (retry_pnfs) {
1012                 dprintk("%s Reset task %5u for i/o through pNFS "
1013                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1014                         hdr->task.tk_pid,
1015                         hdr->inode->i_sb->s_id,
1016                         (unsigned long long)NFS_FILEID(hdr->inode),
1017                         hdr->args.count,
1018                         (unsigned long long)hdr->args.offset);
1019
1020                 hdr->completion_ops->reschedule_io(hdr);
1021                 return;
1022         }
1023
1024         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1025                 dprintk("%s Reset task %5u for i/o through MDS "
1026                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1027                         hdr->task.tk_pid,
1028                         hdr->inode->i_sb->s_id,
1029                         (unsigned long long)NFS_FILEID(hdr->inode),
1030                         hdr->args.count,
1031                         (unsigned long long)hdr->args.offset);
1032
1033                 trace_pnfs_mds_fallback_write_done(hdr->inode,
1034                                 hdr->args.offset, hdr->args.count,
1035                                 IOMODE_RW, NFS_I(hdr->inode)->layout,
1036                                 hdr->lseg);
1037                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1038         }
1039 }
1040
1041 static void ff_layout_resend_pnfs_read(struct nfs_pgio_header *hdr)
1042 {
1043         u32 idx = hdr->pgio_mirror_idx + 1;
1044         u32 new_idx = 0;
1045
1046         if (ff_layout_choose_any_ds_for_read(hdr->lseg, idx, &new_idx))
1047                 ff_layout_send_layouterror(hdr->lseg);
1048         else
1049                 pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1050         pnfs_read_resend_pnfs(hdr, new_idx);
1051 }
1052
1053 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1054 {
1055         struct rpc_task *task = &hdr->task;
1056
1057         pnfs_layoutcommit_inode(hdr->inode, false);
1058         pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1059
1060         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1061                 dprintk("%s Reset task %5u for i/o through MDS "
1062                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1063                         hdr->task.tk_pid,
1064                         hdr->inode->i_sb->s_id,
1065                         (unsigned long long)NFS_FILEID(hdr->inode),
1066                         hdr->args.count,
1067                         (unsigned long long)hdr->args.offset);
1068
1069                 trace_pnfs_mds_fallback_read_done(hdr->inode,
1070                                 hdr->args.offset, hdr->args.count,
1071                                 IOMODE_READ, NFS_I(hdr->inode)->layout,
1072                                 hdr->lseg);
1073                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1074         }
1075 }
1076
1077 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1078                                            struct nfs4_state *state,
1079                                            struct nfs_client *clp,
1080                                            struct pnfs_layout_segment *lseg,
1081                                            u32 idx)
1082 {
1083         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1084         struct inode *inode = lo->plh_inode;
1085         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1086         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1087
1088         switch (task->tk_status) {
1089         case -NFS4ERR_BADSESSION:
1090         case -NFS4ERR_BADSLOT:
1091         case -NFS4ERR_BAD_HIGH_SLOT:
1092         case -NFS4ERR_DEADSESSION:
1093         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1094         case -NFS4ERR_SEQ_FALSE_RETRY:
1095         case -NFS4ERR_SEQ_MISORDERED:
1096                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1097                         "flags 0x%x\n", __func__, task->tk_status,
1098                         clp->cl_exchange_flags);
1099                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1100                 break;
1101         case -NFS4ERR_DELAY:
1102         case -NFS4ERR_GRACE:
1103                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1104                 break;
1105         case -NFS4ERR_RETRY_UNCACHED_REP:
1106                 break;
1107         /* Invalidate Layout errors */
1108         case -NFS4ERR_PNFS_NO_LAYOUT:
1109         case -ESTALE:           /* mapped NFS4ERR_STALE */
1110         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1111         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1112         case -NFS4ERR_FHEXPIRED:
1113         case -NFS4ERR_WRONG_TYPE:
1114                 dprintk("%s Invalid layout error %d\n", __func__,
1115                         task->tk_status);
1116                 /*
1117                  * Destroy layout so new i/o will get a new layout.
1118                  * Layout will not be destroyed until all current lseg
1119                  * references are put. Mark layout as invalid to resend failed
1120                  * i/o and all i/o waiting on the slot table to the MDS until
1121                  * layout is destroyed and a new valid layout is obtained.
1122                  */
1123                 pnfs_destroy_layout(NFS_I(inode));
1124                 rpc_wake_up(&tbl->slot_tbl_waitq);
1125                 goto reset;
1126         /* RPC connection errors */
1127         case -ECONNREFUSED:
1128         case -EHOSTDOWN:
1129         case -EHOSTUNREACH:
1130         case -ENETUNREACH:
1131         case -EIO:
1132         case -ETIMEDOUT:
1133         case -EPIPE:
1134         case -EPROTO:
1135         case -ENODEV:
1136                 dprintk("%s DS connection error %d\n", __func__,
1137                         task->tk_status);
1138                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1139                                 &devid->deviceid);
1140                 rpc_wake_up(&tbl->slot_tbl_waitq);
1141                 fallthrough;
1142         default:
1143                 if (ff_layout_avoid_mds_available_ds(lseg))
1144                         return -NFS4ERR_RESET_TO_PNFS;
1145 reset:
1146                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1147                         task->tk_status);
1148                 return -NFS4ERR_RESET_TO_MDS;
1149         }
1150         task->tk_status = 0;
1151         return -EAGAIN;
1152 }
1153
1154 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1155 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1156                                            struct pnfs_layout_segment *lseg,
1157                                            u32 idx)
1158 {
1159         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1160
1161         switch (task->tk_status) {
1162         /* File access problems. Don't mark the device as unavailable */
1163         case -EACCES:
1164         case -ESTALE:
1165         case -EISDIR:
1166         case -EBADHANDLE:
1167         case -ELOOP:
1168         case -ENOSPC:
1169                 break;
1170         case -EJUKEBOX:
1171                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1172                 goto out_retry;
1173         default:
1174                 dprintk("%s DS connection error %d\n", __func__,
1175                         task->tk_status);
1176                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1177                                 &devid->deviceid);
1178         }
1179         /* FIXME: Need to prevent infinite looping here. */
1180         return -NFS4ERR_RESET_TO_PNFS;
1181 out_retry:
1182         task->tk_status = 0;
1183         rpc_restart_call_prepare(task);
1184         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1185         return -EAGAIN;
1186 }
1187
1188 static int ff_layout_async_handle_error(struct rpc_task *task,
1189                                         struct nfs4_state *state,
1190                                         struct nfs_client *clp,
1191                                         struct pnfs_layout_segment *lseg,
1192                                         u32 idx)
1193 {
1194         int vers = clp->cl_nfs_mod->rpc_vers->number;
1195
1196         if (task->tk_status >= 0) {
1197                 ff_layout_mark_ds_reachable(lseg, idx);
1198                 return 0;
1199         }
1200
1201         /* Handle the case of an invalid layout segment */
1202         if (!pnfs_is_valid_lseg(lseg))
1203                 return -NFS4ERR_RESET_TO_PNFS;
1204
1205         switch (vers) {
1206         case 3:
1207                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1208         case 4:
1209                 return ff_layout_async_handle_error_v4(task, state, clp,
1210                                                        lseg, idx);
1211         default:
1212                 /* should never happen */
1213                 WARN_ON_ONCE(1);
1214                 return 0;
1215         }
1216 }
1217
1218 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1219                                         u32 idx, u64 offset, u64 length,
1220                                         u32 *op_status, int opnum, int error)
1221 {
1222         struct nfs4_ff_layout_mirror *mirror;
1223         u32 status = *op_status;
1224         int err;
1225
1226         if (status == 0) {
1227                 switch (error) {
1228                 case -ETIMEDOUT:
1229                 case -EPFNOSUPPORT:
1230                 case -EPROTONOSUPPORT:
1231                 case -EOPNOTSUPP:
1232                 case -ECONNREFUSED:
1233                 case -ECONNRESET:
1234                 case -EHOSTDOWN:
1235                 case -EHOSTUNREACH:
1236                 case -ENETUNREACH:
1237                 case -EADDRINUSE:
1238                 case -ENOBUFS:
1239                 case -EPIPE:
1240                 case -EPERM:
1241                 case -EPROTO:
1242                 case -ENODEV:
1243                         *op_status = status = NFS4ERR_NXIO;
1244                         break;
1245                 case -EACCES:
1246                         *op_status = status = NFS4ERR_ACCESS;
1247                         break;
1248                 default:
1249                         return;
1250                 }
1251         }
1252
1253         mirror = FF_LAYOUT_COMP(lseg, idx);
1254         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1255                                        mirror, offset, length, status, opnum,
1256                                        nfs_io_gfp_mask());
1257
1258         switch (status) {
1259         case NFS4ERR_DELAY:
1260         case NFS4ERR_GRACE:
1261                 break;
1262         case NFS4ERR_NXIO:
1263                 ff_layout_mark_ds_unreachable(lseg, idx);
1264                 /*
1265                  * Don't return the layout if this is a read and we still
1266                  * have layouts to try
1267                  */
1268                 if (opnum == OP_READ)
1269                         break;
1270                 fallthrough;
1271         default:
1272                 pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode,
1273                                                   lseg);
1274         }
1275
1276         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1277 }
1278
1279 /* NFS_PROTO call done callback routines */
1280 static int ff_layout_read_done_cb(struct rpc_task *task,
1281                                 struct nfs_pgio_header *hdr)
1282 {
1283         int err;
1284
1285         if (task->tk_status < 0) {
1286                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1287                                             hdr->args.offset, hdr->args.count,
1288                                             &hdr->res.op_status, OP_READ,
1289                                             task->tk_status);
1290                 trace_ff_layout_read_error(hdr);
1291         }
1292
1293         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1294                                            hdr->ds_clp, hdr->lseg,
1295                                            hdr->pgio_mirror_idx);
1296
1297         trace_nfs4_pnfs_read(hdr, err);
1298         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1299         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1300         switch (err) {
1301         case -NFS4ERR_RESET_TO_PNFS:
1302                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1303                 return task->tk_status;
1304         case -NFS4ERR_RESET_TO_MDS:
1305                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1306                 return task->tk_status;
1307         case -EAGAIN:
1308                 goto out_eagain;
1309         }
1310
1311         return 0;
1312 out_eagain:
1313         rpc_restart_call_prepare(task);
1314         return -EAGAIN;
1315 }
1316
1317 static bool
1318 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1319 {
1320         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1321 }
1322
1323 /*
1324  * We reference the rpc_cred of the first WRITE that triggers the need for
1325  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1326  * rfc5661 is not clear about which credential should be used.
1327  *
1328  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1329  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1330  * we always send layoutcommit after DS writes.
1331  */
1332 static void
1333 ff_layout_set_layoutcommit(struct inode *inode,
1334                 struct pnfs_layout_segment *lseg,
1335                 loff_t end_offset)
1336 {
1337         if (!ff_layout_need_layoutcommit(lseg))
1338                 return;
1339
1340         pnfs_set_layoutcommit(inode, lseg, end_offset);
1341         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1342                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1343 }
1344
1345 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1346                 struct nfs_pgio_header *hdr)
1347 {
1348         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1349                 return;
1350         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1351                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1352                         hdr->args.count,
1353                         task->tk_start);
1354 }
1355
1356 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1357                 struct nfs_pgio_header *hdr)
1358 {
1359         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1360                 return;
1361         nfs4_ff_layout_stat_io_end_read(task,
1362                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1363                         hdr->args.count,
1364                         hdr->res.count);
1365         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1366 }
1367
1368 static int ff_layout_read_prepare_common(struct rpc_task *task,
1369                                          struct nfs_pgio_header *hdr)
1370 {
1371         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1372                 rpc_exit(task, -EIO);
1373                 return -EIO;
1374         }
1375
1376         ff_layout_read_record_layoutstats_start(task, hdr);
1377         return 0;
1378 }
1379
1380 /*
1381  * Call ops for the async read/write cases
1382  * In the case of dense layouts, the offset needs to be reset to its
1383  * original value.
1384  */
1385 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1386 {
1387         struct nfs_pgio_header *hdr = data;
1388
1389         if (ff_layout_read_prepare_common(task, hdr))
1390                 return;
1391
1392         rpc_call_start(task);
1393 }
1394
1395 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1396 {
1397         struct nfs_pgio_header *hdr = data;
1398
1399         if (nfs4_setup_sequence(hdr->ds_clp,
1400                                 &hdr->args.seq_args,
1401                                 &hdr->res.seq_res,
1402                                 task))
1403                 return;
1404
1405         ff_layout_read_prepare_common(task, hdr);
1406 }
1407
1408 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1409 {
1410         struct nfs_pgio_header *hdr = data;
1411
1412         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1413             task->tk_status == 0) {
1414                 nfs4_sequence_done(task, &hdr->res.seq_res);
1415                 return;
1416         }
1417
1418         /* Note this may cause RPC to be resent */
1419         hdr->mds_ops->rpc_call_done(task, hdr);
1420 }
1421
1422 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1423 {
1424         struct nfs_pgio_header *hdr = data;
1425
1426         ff_layout_read_record_layoutstats_done(task, hdr);
1427         rpc_count_iostats_metrics(task,
1428             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1429 }
1430
1431 static void ff_layout_read_release(void *data)
1432 {
1433         struct nfs_pgio_header *hdr = data;
1434
1435         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1436         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags))
1437                 ff_layout_resend_pnfs_read(hdr);
1438         else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1439                 ff_layout_reset_read(hdr);
1440         pnfs_generic_rw_release(data);
1441 }
1442
1443
1444 static int ff_layout_write_done_cb(struct rpc_task *task,
1445                                 struct nfs_pgio_header *hdr)
1446 {
1447         loff_t end_offs = 0;
1448         int err;
1449
1450         if (task->tk_status < 0) {
1451                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1452                                             hdr->args.offset, hdr->args.count,
1453                                             &hdr->res.op_status, OP_WRITE,
1454                                             task->tk_status);
1455                 trace_ff_layout_write_error(hdr);
1456         }
1457
1458         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1459                                            hdr->ds_clp, hdr->lseg,
1460                                            hdr->pgio_mirror_idx);
1461
1462         trace_nfs4_pnfs_write(hdr, err);
1463         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1464         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1465         switch (err) {
1466         case -NFS4ERR_RESET_TO_PNFS:
1467                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1468                 return task->tk_status;
1469         case -NFS4ERR_RESET_TO_MDS:
1470                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1471                 return task->tk_status;
1472         case -EAGAIN:
1473                 return -EAGAIN;
1474         }
1475
1476         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1477             hdr->res.verf->committed == NFS_DATA_SYNC)
1478                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1479
1480         /* Note: if the write is unstable, don't set end_offs until commit */
1481         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1482
1483         /* zero out fattr since we don't care DS attr at all */
1484         hdr->fattr.valid = 0;
1485         if (task->tk_status >= 0)
1486                 nfs_writeback_update_inode(hdr);
1487
1488         return 0;
1489 }
1490
1491 static int ff_layout_commit_done_cb(struct rpc_task *task,
1492                                      struct nfs_commit_data *data)
1493 {
1494         int err;
1495
1496         if (task->tk_status < 0) {
1497                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1498                                             data->args.offset, data->args.count,
1499                                             &data->res.op_status, OP_COMMIT,
1500                                             task->tk_status);
1501                 trace_ff_layout_commit_error(data);
1502         }
1503
1504         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1505                                            data->lseg, data->ds_commit_index);
1506
1507         trace_nfs4_pnfs_commit_ds(data, err);
1508         switch (err) {
1509         case -NFS4ERR_RESET_TO_PNFS:
1510                 pnfs_generic_prepare_to_resend_writes(data);
1511                 return -EAGAIN;
1512         case -NFS4ERR_RESET_TO_MDS:
1513                 pnfs_generic_prepare_to_resend_writes(data);
1514                 return -EAGAIN;
1515         case -EAGAIN:
1516                 rpc_restart_call_prepare(task);
1517                 return -EAGAIN;
1518         }
1519
1520         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1521
1522         return 0;
1523 }
1524
1525 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1526                 struct nfs_pgio_header *hdr)
1527 {
1528         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1529                 return;
1530         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1531                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1532                         hdr->args.count,
1533                         task->tk_start);
1534 }
1535
1536 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1537                 struct nfs_pgio_header *hdr)
1538 {
1539         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1540                 return;
1541         nfs4_ff_layout_stat_io_end_write(task,
1542                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1543                         hdr->args.count, hdr->res.count,
1544                         hdr->res.verf->committed);
1545         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1546 }
1547
1548 static int ff_layout_write_prepare_common(struct rpc_task *task,
1549                                           struct nfs_pgio_header *hdr)
1550 {
1551         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1552                 rpc_exit(task, -EIO);
1553                 return -EIO;
1554         }
1555
1556         ff_layout_write_record_layoutstats_start(task, hdr);
1557         return 0;
1558 }
1559
1560 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1561 {
1562         struct nfs_pgio_header *hdr = data;
1563
1564         if (ff_layout_write_prepare_common(task, hdr))
1565                 return;
1566
1567         rpc_call_start(task);
1568 }
1569
1570 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1571 {
1572         struct nfs_pgio_header *hdr = data;
1573
1574         if (nfs4_setup_sequence(hdr->ds_clp,
1575                                 &hdr->args.seq_args,
1576                                 &hdr->res.seq_res,
1577                                 task))
1578                 return;
1579
1580         ff_layout_write_prepare_common(task, hdr);
1581 }
1582
1583 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1584 {
1585         struct nfs_pgio_header *hdr = data;
1586
1587         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1588             task->tk_status == 0) {
1589                 nfs4_sequence_done(task, &hdr->res.seq_res);
1590                 return;
1591         }
1592
1593         /* Note this may cause RPC to be resent */
1594         hdr->mds_ops->rpc_call_done(task, hdr);
1595 }
1596
1597 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1598 {
1599         struct nfs_pgio_header *hdr = data;
1600
1601         ff_layout_write_record_layoutstats_done(task, hdr);
1602         rpc_count_iostats_metrics(task,
1603             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1604 }
1605
1606 static void ff_layout_write_release(void *data)
1607 {
1608         struct nfs_pgio_header *hdr = data;
1609
1610         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1611         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1612                 ff_layout_send_layouterror(hdr->lseg);
1613                 ff_layout_reset_write(hdr, true);
1614         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1615                 ff_layout_reset_write(hdr, false);
1616         pnfs_generic_rw_release(data);
1617 }
1618
1619 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1620                 struct nfs_commit_data *cdata)
1621 {
1622         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1623                 return;
1624         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1625                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1626                         0, task->tk_start);
1627 }
1628
1629 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1630                 struct nfs_commit_data *cdata)
1631 {
1632         struct nfs_page *req;
1633         __u64 count = 0;
1634
1635         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1636                 return;
1637
1638         if (task->tk_status == 0) {
1639                 list_for_each_entry(req, &cdata->pages, wb_list)
1640                         count += req->wb_bytes;
1641         }
1642         nfs4_ff_layout_stat_io_end_write(task,
1643                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1644                         count, count, NFS_FILE_SYNC);
1645         set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1646 }
1647
1648 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1649                 struct nfs_commit_data *cdata)
1650 {
1651         ff_layout_commit_record_layoutstats_start(task, cdata);
1652 }
1653
1654 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1655 {
1656         ff_layout_commit_prepare_common(task, data);
1657         rpc_call_start(task);
1658 }
1659
1660 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1661 {
1662         struct nfs_commit_data *wdata = data;
1663
1664         if (nfs4_setup_sequence(wdata->ds_clp,
1665                                 &wdata->args.seq_args,
1666                                 &wdata->res.seq_res,
1667                                 task))
1668                 return;
1669         ff_layout_commit_prepare_common(task, data);
1670 }
1671
1672 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1673 {
1674         pnfs_generic_write_commit_done(task, data);
1675 }
1676
1677 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1678 {
1679         struct nfs_commit_data *cdata = data;
1680
1681         ff_layout_commit_record_layoutstats_done(task, cdata);
1682         rpc_count_iostats_metrics(task,
1683             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1684 }
1685
1686 static void ff_layout_commit_release(void *data)
1687 {
1688         struct nfs_commit_data *cdata = data;
1689
1690         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1691         pnfs_generic_commit_release(data);
1692 }
1693
1694 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1695         .rpc_call_prepare = ff_layout_read_prepare_v3,
1696         .rpc_call_done = ff_layout_read_call_done,
1697         .rpc_count_stats = ff_layout_read_count_stats,
1698         .rpc_release = ff_layout_read_release,
1699 };
1700
1701 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1702         .rpc_call_prepare = ff_layout_read_prepare_v4,
1703         .rpc_call_done = ff_layout_read_call_done,
1704         .rpc_count_stats = ff_layout_read_count_stats,
1705         .rpc_release = ff_layout_read_release,
1706 };
1707
1708 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1709         .rpc_call_prepare = ff_layout_write_prepare_v3,
1710         .rpc_call_done = ff_layout_write_call_done,
1711         .rpc_count_stats = ff_layout_write_count_stats,
1712         .rpc_release = ff_layout_write_release,
1713 };
1714
1715 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1716         .rpc_call_prepare = ff_layout_write_prepare_v4,
1717         .rpc_call_done = ff_layout_write_call_done,
1718         .rpc_count_stats = ff_layout_write_count_stats,
1719         .rpc_release = ff_layout_write_release,
1720 };
1721
1722 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1723         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1724         .rpc_call_done = ff_layout_commit_done,
1725         .rpc_count_stats = ff_layout_commit_count_stats,
1726         .rpc_release = ff_layout_commit_release,
1727 };
1728
1729 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1730         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1731         .rpc_call_done = ff_layout_commit_done,
1732         .rpc_count_stats = ff_layout_commit_count_stats,
1733         .rpc_release = ff_layout_commit_release,
1734 };
1735
1736 static enum pnfs_try_status
1737 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1738 {
1739         struct pnfs_layout_segment *lseg = hdr->lseg;
1740         struct nfs4_pnfs_ds *ds;
1741         struct rpc_clnt *ds_clnt;
1742         struct nfs4_ff_layout_mirror *mirror;
1743         const struct cred *ds_cred;
1744         loff_t offset = hdr->args.offset;
1745         u32 idx = hdr->pgio_mirror_idx;
1746         int vers;
1747         struct nfs_fh *fh;
1748
1749         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1750                 __func__, hdr->inode->i_ino,
1751                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1752
1753         mirror = FF_LAYOUT_COMP(lseg, idx);
1754         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
1755         if (!ds)
1756                 goto out_failed;
1757
1758         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1759                                                    hdr->inode);
1760         if (IS_ERR(ds_clnt))
1761                 goto out_failed;
1762
1763         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1764         if (!ds_cred)
1765                 goto out_failed;
1766
1767         vers = nfs4_ff_layout_ds_version(mirror);
1768
1769         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1770                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1771
1772         hdr->pgio_done_cb = ff_layout_read_done_cb;
1773         refcount_inc(&ds->ds_clp->cl_count);
1774         hdr->ds_clp = ds->ds_clp;
1775         fh = nfs4_ff_layout_select_ds_fh(mirror);
1776         if (fh)
1777                 hdr->args.fh = fh;
1778
1779         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1780
1781         /*
1782          * Note that if we ever decide to split across DSes,
1783          * then we may need to handle dense-like offsets.
1784          */
1785         hdr->args.offset = offset;
1786         hdr->mds_offset = offset;
1787
1788         /* Perform an asynchronous read to ds */
1789         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1790                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1791                                       &ff_layout_read_call_ops_v4,
1792                           0, RPC_TASK_SOFTCONN);
1793         put_cred(ds_cred);
1794         return PNFS_ATTEMPTED;
1795
1796 out_failed:
1797         if (ff_layout_avoid_mds_available_ds(lseg))
1798                 return PNFS_TRY_AGAIN;
1799         trace_pnfs_mds_fallback_read_pagelist(hdr->inode,
1800                         hdr->args.offset, hdr->args.count,
1801                         IOMODE_READ, NFS_I(hdr->inode)->layout, lseg);
1802         return PNFS_NOT_ATTEMPTED;
1803 }
1804
1805 /* Perform async writes. */
1806 static enum pnfs_try_status
1807 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1808 {
1809         struct pnfs_layout_segment *lseg = hdr->lseg;
1810         struct nfs4_pnfs_ds *ds;
1811         struct rpc_clnt *ds_clnt;
1812         struct nfs4_ff_layout_mirror *mirror;
1813         const struct cred *ds_cred;
1814         loff_t offset = hdr->args.offset;
1815         int vers;
1816         struct nfs_fh *fh;
1817         u32 idx = hdr->pgio_mirror_idx;
1818
1819         mirror = FF_LAYOUT_COMP(lseg, idx);
1820         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1821         if (!ds)
1822                 goto out_failed;
1823
1824         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1825                                                    hdr->inode);
1826         if (IS_ERR(ds_clnt))
1827                 goto out_failed;
1828
1829         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1830         if (!ds_cred)
1831                 goto out_failed;
1832
1833         vers = nfs4_ff_layout_ds_version(mirror);
1834
1835         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1836                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1837                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1838                 vers);
1839
1840         hdr->pgio_done_cb = ff_layout_write_done_cb;
1841         refcount_inc(&ds->ds_clp->cl_count);
1842         hdr->ds_clp = ds->ds_clp;
1843         hdr->ds_commit_idx = idx;
1844         fh = nfs4_ff_layout_select_ds_fh(mirror);
1845         if (fh)
1846                 hdr->args.fh = fh;
1847
1848         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1849
1850         /*
1851          * Note that if we ever decide to split across DSes,
1852          * then we may need to handle dense-like offsets.
1853          */
1854         hdr->args.offset = offset;
1855
1856         /* Perform an asynchronous write */
1857         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1858                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1859                                       &ff_layout_write_call_ops_v4,
1860                           sync, RPC_TASK_SOFTCONN);
1861         put_cred(ds_cred);
1862         return PNFS_ATTEMPTED;
1863
1864 out_failed:
1865         if (ff_layout_avoid_mds_available_ds(lseg))
1866                 return PNFS_TRY_AGAIN;
1867         trace_pnfs_mds_fallback_write_pagelist(hdr->inode,
1868                         hdr->args.offset, hdr->args.count,
1869                         IOMODE_RW, NFS_I(hdr->inode)->layout, lseg);
1870         return PNFS_NOT_ATTEMPTED;
1871 }
1872
1873 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1874 {
1875         return i;
1876 }
1877
1878 static struct nfs_fh *
1879 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1880 {
1881         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1882
1883         /* FIXME: Assume that there is only one NFS version available
1884          * for the DS.
1885          */
1886         return &flseg->mirror_array[i]->fh_versions[0];
1887 }
1888
1889 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1890 {
1891         struct pnfs_layout_segment *lseg = data->lseg;
1892         struct nfs4_pnfs_ds *ds;
1893         struct rpc_clnt *ds_clnt;
1894         struct nfs4_ff_layout_mirror *mirror;
1895         const struct cred *ds_cred;
1896         u32 idx;
1897         int vers, ret;
1898         struct nfs_fh *fh;
1899
1900         if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1901             test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1902                 goto out_err;
1903
1904         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1905         mirror = FF_LAYOUT_COMP(lseg, idx);
1906         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1907         if (!ds)
1908                 goto out_err;
1909
1910         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1911                                                    data->inode);
1912         if (IS_ERR(ds_clnt))
1913                 goto out_err;
1914
1915         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
1916         if (!ds_cred)
1917                 goto out_err;
1918
1919         vers = nfs4_ff_layout_ds_version(mirror);
1920
1921         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1922                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1923                 vers);
1924         data->commit_done_cb = ff_layout_commit_done_cb;
1925         data->cred = ds_cred;
1926         refcount_inc(&ds->ds_clp->cl_count);
1927         data->ds_clp = ds->ds_clp;
1928         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1929         if (fh)
1930                 data->args.fh = fh;
1931
1932         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1933                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1934                                                &ff_layout_commit_call_ops_v4,
1935                                    how, RPC_TASK_SOFTCONN);
1936         put_cred(ds_cred);
1937         return ret;
1938 out_err:
1939         pnfs_generic_prepare_to_resend_writes(data);
1940         pnfs_generic_commit_release(data);
1941         return -EAGAIN;
1942 }
1943
1944 static int
1945 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1946                            int how, struct nfs_commit_info *cinfo)
1947 {
1948         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1949                                             ff_layout_initiate_commit);
1950 }
1951
1952 static struct pnfs_ds_commit_info *
1953 ff_layout_get_ds_info(struct inode *inode)
1954 {
1955         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1956
1957         if (layout == NULL)
1958                 return NULL;
1959
1960         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1961 }
1962
1963 static void
1964 ff_layout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
1965                 struct pnfs_layout_segment *lseg)
1966 {
1967         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1968         struct inode *inode = lseg->pls_layout->plh_inode;
1969         struct pnfs_commit_array *array, *new;
1970
1971         new = pnfs_alloc_commit_array(flseg->mirror_array_cnt,
1972                                       nfs_io_gfp_mask());
1973         if (new) {
1974                 spin_lock(&inode->i_lock);
1975                 array = pnfs_add_commit_array(fl_cinfo, new, lseg);
1976                 spin_unlock(&inode->i_lock);
1977                 if (array != new)
1978                         pnfs_free_commit_array(new);
1979         }
1980 }
1981
1982 static void
1983 ff_layout_release_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
1984                 struct inode *inode)
1985 {
1986         spin_lock(&inode->i_lock);
1987         pnfs_generic_ds_cinfo_destroy(fl_cinfo);
1988         spin_unlock(&inode->i_lock);
1989 }
1990
1991 static void
1992 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1993 {
1994         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1995                                                   id_node));
1996 }
1997
1998 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
1999                                   const struct nfs4_layoutreturn_args *args,
2000                                   const struct nfs4_flexfile_layoutreturn_args *ff_args)
2001 {
2002         __be32 *start;
2003
2004         start = xdr_reserve_space(xdr, 4);
2005         if (unlikely(!start))
2006                 return -E2BIG;
2007
2008         *start = cpu_to_be32(ff_args->num_errors);
2009         /* This assume we always return _ALL_ layouts */
2010         return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
2011 }
2012
2013 static void
2014 encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
2015 {
2016         WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
2017 }
2018
2019 static void
2020 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
2021                             const nfs4_stateid *stateid,
2022                             const struct nfs42_layoutstat_devinfo *devinfo)
2023 {
2024         __be32 *p;
2025
2026         p = xdr_reserve_space(xdr, 8 + 8);
2027         p = xdr_encode_hyper(p, devinfo->offset);
2028         p = xdr_encode_hyper(p, devinfo->length);
2029         encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
2030         p = xdr_reserve_space(xdr, 4*8);
2031         p = xdr_encode_hyper(p, devinfo->read_count);
2032         p = xdr_encode_hyper(p, devinfo->read_bytes);
2033         p = xdr_encode_hyper(p, devinfo->write_count);
2034         p = xdr_encode_hyper(p, devinfo->write_bytes);
2035         encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
2036 }
2037
2038 static void
2039 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
2040                             const nfs4_stateid *stateid,
2041                             const struct nfs42_layoutstat_devinfo *devinfo)
2042 {
2043         ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
2044         ff_layout_encode_ff_layoutupdate(xdr, devinfo,
2045                         devinfo->ld_private.data);
2046 }
2047
2048 /* report nothing for now */
2049 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
2050                 const struct nfs4_layoutreturn_args *args,
2051                 struct nfs4_flexfile_layoutreturn_args *ff_args)
2052 {
2053         __be32 *p;
2054         int i;
2055
2056         p = xdr_reserve_space(xdr, 4);
2057         *p = cpu_to_be32(ff_args->num_dev);
2058         for (i = 0; i < ff_args->num_dev; i++)
2059                 ff_layout_encode_ff_iostat(xdr,
2060                                 &args->layout->plh_stateid,
2061                                 &ff_args->devinfo[i]);
2062 }
2063
2064 static void
2065 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
2066                 unsigned int num_entries)
2067 {
2068         unsigned int i;
2069
2070         for (i = 0; i < num_entries; i++) {
2071                 if (!devinfo[i].ld_private.ops)
2072                         continue;
2073                 if (!devinfo[i].ld_private.ops->free)
2074                         continue;
2075                 devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2076         }
2077 }
2078
2079 static struct nfs4_deviceid_node *
2080 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2081                               struct pnfs_device *pdev, gfp_t gfp_flags)
2082 {
2083         struct nfs4_ff_layout_ds *dsaddr;
2084
2085         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2086         if (!dsaddr)
2087                 return NULL;
2088         return &dsaddr->id_node;
2089 }
2090
2091 static void
2092 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2093                 const void *voidargs,
2094                 const struct nfs4_xdr_opaque_data *ff_opaque)
2095 {
2096         const struct nfs4_layoutreturn_args *args = voidargs;
2097         struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2098         struct xdr_buf tmp_buf = {
2099                 .head = {
2100                         [0] = {
2101                                 .iov_base = page_address(ff_args->pages[0]),
2102                         },
2103                 },
2104                 .buflen = PAGE_SIZE,
2105         };
2106         struct xdr_stream tmp_xdr;
2107         __be32 *start;
2108
2109         dprintk("%s: Begin\n", __func__);
2110
2111         xdr_init_encode(&tmp_xdr, &tmp_buf, NULL, NULL);
2112
2113         ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2114         ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2115
2116         start = xdr_reserve_space(xdr, 4);
2117         *start = cpu_to_be32(tmp_buf.len);
2118         xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2119
2120         dprintk("%s: Return\n", __func__);
2121 }
2122
2123 static void
2124 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2125 {
2126         struct nfs4_flexfile_layoutreturn_args *ff_args;
2127
2128         if (!args->data)
2129                 return;
2130         ff_args = args->data;
2131         args->data = NULL;
2132
2133         ff_layout_free_ds_ioerr(&ff_args->errors);
2134         ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2135
2136         put_page(ff_args->pages[0]);
2137         kfree(ff_args);
2138 }
2139
2140 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2141         .encode = ff_layout_encode_layoutreturn,
2142         .free = ff_layout_free_layoutreturn,
2143 };
2144
2145 static int
2146 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2147 {
2148         struct nfs4_flexfile_layoutreturn_args *ff_args;
2149         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2150
2151         ff_args = kmalloc(sizeof(*ff_args), nfs_io_gfp_mask());
2152         if (!ff_args)
2153                 goto out_nomem;
2154         ff_args->pages[0] = alloc_page(nfs_io_gfp_mask());
2155         if (!ff_args->pages[0])
2156                 goto out_nomem_free;
2157
2158         INIT_LIST_HEAD(&ff_args->errors);
2159         ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2160                         &args->range, &ff_args->errors,
2161                         FF_LAYOUTRETURN_MAXERR);
2162
2163         spin_lock(&args->inode->i_lock);
2164         ff_args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2165                         &ff_args->devinfo[0], ARRAY_SIZE(ff_args->devinfo));
2166         spin_unlock(&args->inode->i_lock);
2167
2168         args->ld_private->ops = &layoutreturn_ops;
2169         args->ld_private->data = ff_args;
2170         return 0;
2171 out_nomem_free:
2172         kfree(ff_args);
2173 out_nomem:
2174         return -ENOMEM;
2175 }
2176
2177 #ifdef CONFIG_NFS_V4_2
2178 void
2179 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2180 {
2181         struct pnfs_layout_hdr *lo = lseg->pls_layout;
2182         struct nfs42_layout_error *errors;
2183         LIST_HEAD(head);
2184
2185         if (!nfs_server_capable(lo->plh_inode, NFS_CAP_LAYOUTERROR))
2186                 return;
2187         ff_layout_fetch_ds_ioerr(lo, &lseg->pls_range, &head, -1);
2188         if (list_empty(&head))
2189                 return;
2190
2191         errors = kmalloc_array(NFS42_LAYOUTERROR_MAX, sizeof(*errors),
2192                                nfs_io_gfp_mask());
2193         if (errors != NULL) {
2194                 const struct nfs4_ff_layout_ds_err *pos;
2195                 size_t n = 0;
2196
2197                 list_for_each_entry(pos, &head, list) {
2198                         errors[n].offset = pos->offset;
2199                         errors[n].length = pos->length;
2200                         nfs4_stateid_copy(&errors[n].stateid, &pos->stateid);
2201                         errors[n].errors[0].dev_id = pos->deviceid;
2202                         errors[n].errors[0].status = pos->status;
2203                         errors[n].errors[0].opnum = pos->opnum;
2204                         n++;
2205                         if (!list_is_last(&pos->list, &head) &&
2206                             n < NFS42_LAYOUTERROR_MAX)
2207                                 continue;
2208                         if (nfs42_proc_layouterror(lseg, errors, n) < 0)
2209                                 break;
2210                         n = 0;
2211                 }
2212                 kfree(errors);
2213         }
2214         ff_layout_free_ds_ioerr(&head);
2215 }
2216 #else
2217 void
2218 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2219 {
2220 }
2221 #endif
2222
2223 static int
2224 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2225 {
2226         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2227
2228         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2229 }
2230
2231 static size_t
2232 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2233                           const int buflen)
2234 {
2235         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2236         const struct in6_addr *addr = &sin6->sin6_addr;
2237
2238         /*
2239          * RFC 4291, Section 2.2.2
2240          *
2241          * Shorthanded ANY address
2242          */
2243         if (ipv6_addr_any(addr))
2244                 return snprintf(buf, buflen, "::");
2245
2246         /*
2247          * RFC 4291, Section 2.2.2
2248          *
2249          * Shorthanded loopback address
2250          */
2251         if (ipv6_addr_loopback(addr))
2252                 return snprintf(buf, buflen, "::1");
2253
2254         /*
2255          * RFC 4291, Section 2.2.3
2256          *
2257          * Special presentation address format for mapped v4
2258          * addresses.
2259          */
2260         if (ipv6_addr_v4mapped(addr))
2261                 return snprintf(buf, buflen, "::ffff:%pI4",
2262                                         &addr->s6_addr32[3]);
2263
2264         /*
2265          * RFC 4291, Section 2.2.1
2266          */
2267         return snprintf(buf, buflen, "%pI6c", addr);
2268 }
2269
2270 /* Derived from rpc_sockaddr2uaddr */
2271 static void
2272 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2273 {
2274         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2275         char portbuf[RPCBIND_MAXUADDRPLEN];
2276         char addrbuf[RPCBIND_MAXUADDRLEN];
2277         unsigned short port;
2278         int len, netid_len;
2279         __be32 *p;
2280
2281         switch (sap->sa_family) {
2282         case AF_INET:
2283                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2284                         return;
2285                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2286                 break;
2287         case AF_INET6:
2288                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2289                         return;
2290                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2291                 break;
2292         default:
2293                 WARN_ON_ONCE(1);
2294                 return;
2295         }
2296
2297         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2298         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2299
2300         netid_len = strlen(da->da_netid);
2301         p = xdr_reserve_space(xdr, 4 + netid_len);
2302         xdr_encode_opaque(p, da->da_netid, netid_len);
2303
2304         p = xdr_reserve_space(xdr, 4 + len);
2305         xdr_encode_opaque(p, addrbuf, len);
2306 }
2307
2308 static void
2309 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2310                          ktime_t t)
2311 {
2312         struct timespec64 ts;
2313         __be32 *p;
2314
2315         p = xdr_reserve_space(xdr, 12);
2316         ts = ktime_to_timespec64(t);
2317         p = xdr_encode_hyper(p, ts.tv_sec);
2318         *p++ = cpu_to_be32(ts.tv_nsec);
2319 }
2320
2321 static void
2322 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2323                             struct nfs4_ff_io_stat *stat)
2324 {
2325         __be32 *p;
2326
2327         p = xdr_reserve_space(xdr, 5 * 8);
2328         p = xdr_encode_hyper(p, stat->ops_requested);
2329         p = xdr_encode_hyper(p, stat->bytes_requested);
2330         p = xdr_encode_hyper(p, stat->ops_completed);
2331         p = xdr_encode_hyper(p, stat->bytes_completed);
2332         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2333         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2334         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2335 }
2336
2337 static void
2338 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2339                               const struct nfs42_layoutstat_devinfo *devinfo,
2340                               struct nfs4_ff_layout_mirror *mirror)
2341 {
2342         struct nfs4_pnfs_ds_addr *da;
2343         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2344         struct nfs_fh *fh = &mirror->fh_versions[0];
2345         __be32 *p;
2346
2347         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2348         dprintk("%s: DS %s: encoding address %s\n",
2349                 __func__, ds->ds_remotestr, da->da_remotestr);
2350         /* netaddr4 */
2351         ff_layout_encode_netaddr(xdr, da);
2352         /* nfs_fh4 */
2353         p = xdr_reserve_space(xdr, 4 + fh->size);
2354         xdr_encode_opaque(p, fh->data, fh->size);
2355         /* ff_io_latency4 read */
2356         spin_lock(&mirror->lock);
2357         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2358         /* ff_io_latency4 write */
2359         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2360         spin_unlock(&mirror->lock);
2361         /* nfstime4 */
2362         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2363         /* bool */
2364         p = xdr_reserve_space(xdr, 4);
2365         *p = cpu_to_be32(false);
2366 }
2367
2368 static void
2369 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2370                              const struct nfs4_xdr_opaque_data *opaque)
2371 {
2372         struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2373                         struct nfs42_layoutstat_devinfo, ld_private);
2374         __be32 *start;
2375
2376         /* layoutupdate length */
2377         start = xdr_reserve_space(xdr, 4);
2378         ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2379
2380         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2381 }
2382
2383 static void
2384 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2385 {
2386         struct nfs4_ff_layout_mirror *mirror = opaque->data;
2387
2388         ff_layout_put_mirror(mirror);
2389 }
2390
2391 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2392         .encode = ff_layout_encode_layoutstats,
2393         .free   = ff_layout_free_layoutstats,
2394 };
2395
2396 static int
2397 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2398                                struct nfs42_layoutstat_devinfo *devinfo,
2399                                int dev_limit)
2400 {
2401         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2402         struct nfs4_ff_layout_mirror *mirror;
2403         struct nfs4_deviceid_node *dev;
2404         int i = 0;
2405
2406         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2407                 if (i >= dev_limit)
2408                         break;
2409                 if (IS_ERR_OR_NULL(mirror->mirror_ds))
2410                         continue;
2411                 if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags))
2412                         continue;
2413                 /* mirror refcount put in cleanup_layoutstats */
2414                 if (!refcount_inc_not_zero(&mirror->ref))
2415                         continue;
2416                 dev = &mirror->mirror_ds->id_node;
2417                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2418                 devinfo->offset = 0;
2419                 devinfo->length = NFS4_MAX_UINT64;
2420                 spin_lock(&mirror->lock);
2421                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2422                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2423                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2424                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2425                 spin_unlock(&mirror->lock);
2426                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2427                 devinfo->ld_private.ops = &layoutstat_ops;
2428                 devinfo->ld_private.data = mirror;
2429
2430                 devinfo++;
2431                 i++;
2432         }
2433         return i;
2434 }
2435
2436 static int
2437 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2438 {
2439         struct nfs4_flexfile_layout *ff_layout;
2440         const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2441
2442         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2443         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo),
2444                                       nfs_io_gfp_mask());
2445         if (!args->devinfo)
2446                 return -ENOMEM;
2447
2448         spin_lock(&args->inode->i_lock);
2449         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2450         args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2451                         &args->devinfo[0], dev_count);
2452         spin_unlock(&args->inode->i_lock);
2453         if (!args->num_dev) {
2454                 kfree(args->devinfo);
2455                 args->devinfo = NULL;
2456                 return -ENOENT;
2457         }
2458
2459         return 0;
2460 }
2461
2462 static int
2463 ff_layout_set_layoutdriver(struct nfs_server *server,
2464                 const struct nfs_fh *dummy)
2465 {
2466 #if IS_ENABLED(CONFIG_NFS_V4_2)
2467         server->caps |= NFS_CAP_LAYOUTSTATS;
2468 #endif
2469         return 0;
2470 }
2471
2472 static const struct pnfs_commit_ops ff_layout_commit_ops = {
2473         .setup_ds_info          = ff_layout_setup_ds_info,
2474         .release_ds_info        = ff_layout_release_ds_info,
2475         .mark_request_commit    = pnfs_layout_mark_request_commit,
2476         .clear_request_commit   = pnfs_generic_clear_request_commit,
2477         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2478         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2479         .commit_pagelist        = ff_layout_commit_pagelist,
2480 };
2481
2482 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2483         .id                     = LAYOUT_FLEX_FILES,
2484         .name                   = "LAYOUT_FLEX_FILES",
2485         .owner                  = THIS_MODULE,
2486         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
2487         .max_layoutget_response = 4096, /* 1 page or so... */
2488         .set_layoutdriver       = ff_layout_set_layoutdriver,
2489         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2490         .free_layout_hdr        = ff_layout_free_layout_hdr,
2491         .alloc_lseg             = ff_layout_alloc_lseg,
2492         .free_lseg              = ff_layout_free_lseg,
2493         .add_lseg               = ff_layout_add_lseg,
2494         .pg_read_ops            = &ff_layout_pg_read_ops,
2495         .pg_write_ops           = &ff_layout_pg_write_ops,
2496         .get_ds_info            = ff_layout_get_ds_info,
2497         .free_deviceid_node     = ff_layout_free_deviceid_node,
2498         .read_pagelist          = ff_layout_read_pagelist,
2499         .write_pagelist         = ff_layout_write_pagelist,
2500         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2501         .prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2502         .sync                   = pnfs_nfs_generic_sync,
2503         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2504 };
2505
2506 static int __init nfs4flexfilelayout_init(void)
2507 {
2508         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2509                __func__);
2510         return pnfs_register_layoutdriver(&flexfilelayout_type);
2511 }
2512
2513 static void __exit nfs4flexfilelayout_exit(void)
2514 {
2515         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2516                __func__);
2517         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2518 }
2519
2520 MODULE_ALIAS("nfs-layouttype4-4");
2521
2522 MODULE_LICENSE("GPL");
2523 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2524
2525 module_init(nfs4flexfilelayout_init);
2526 module_exit(nfs4flexfilelayout_exit);
2527
2528 module_param(io_maxretrans, ushort, 0644);
2529 MODULE_PARM_DESC(io_maxretrans, "The  number of times the NFSv4.1 client "
2530                         "retries an I/O request before returning an error. ");