fs/nfs/flexfilelayout/flexfilelayout.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Module for pnfs flexfile layout driver.
   4  *
   5  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   6  *
   7  * Tao Peng <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 > sizeof(struct nfs_fh)) {
 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, GFP_KERNEL);
 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, GFP_NOIO);
 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 = pnfs_update_layout(pgio->pg_inode,
 810                                            nfs_req_openctx(req),
 811                                            req_offset(req),
 812                                            req->wb_bytes,
 813                                            IOMODE_READ,
 814                                            strict_iomode,
 815                                            GFP_KERNEL);
 816         if (IS_ERR(pgio->pg_lseg)) {
 817                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 818                 pgio->pg_lseg = NULL;
 819         }
 820 }
 821
 822 static void
 823 ff_layout_pg_check_layout(struct nfs_pageio_descriptor *pgio,
 824                           struct nfs_page *req)
 825 {
 826         pnfs_generic_pg_check_layout(pgio);
 827         pnfs_generic_pg_check_range(pgio, req);
 828 }
 829
 830 static void
 831 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 832                         struct nfs_page *req)
 833 {
 834         struct nfs_pgio_mirror *pgm;
 835         struct nfs4_ff_layout_mirror *mirror;
 836         struct nfs4_pnfs_ds *ds;
 837         u32 ds_idx;
 838
 839 retry:
 840         ff_layout_pg_check_layout(pgio, req);
 841         /* Use full layout for now */
 842         if (!pgio->pg_lseg) {
 843                 ff_layout_pg_get_read(pgio, req, false);
 844                 if (!pgio->pg_lseg)
 845                         goto out_nolseg;
 846         }
 847         if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 848                 ff_layout_pg_get_read(pgio, req, true);
 849                 if (!pgio->pg_lseg)
 850                         goto out_nolseg;
 851         }
 852
 853         ds = ff_layout_get_ds_for_read(pgio, &ds_idx);
 854         if (!ds) {
 855                 if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 856                         goto out_mds;
 857                 pnfs_generic_pg_cleanup(pgio);
 858                 /* Sleep for 1 second before retrying */
 859                 ssleep(1);
 860                 goto retry;
 861         }
 862
 863         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 864         pgm = &pgio->pg_mirrors[0];
 865         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 866
 867         pgio->pg_mirror_idx = ds_idx;
 868
 869         if (NFS_SERVER(pgio->pg_inode)->flags &
 870                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 871                 pgio->pg_maxretrans = io_maxretrans;
 872         return;
 873 out_nolseg:
 874         if (pgio->pg_error < 0)
 875                 return;
 876 out_mds:
 877         trace_pnfs_mds_fallback_pg_init_read(pgio->pg_inode,
 878                         0, NFS4_MAX_UINT64, IOMODE_READ,
 879                         NFS_I(pgio->pg_inode)->layout,
 880                         pgio->pg_lseg);
 881         pgio->pg_maxretrans = 0;
 882         nfs_pageio_reset_read_mds(pgio);
 883 }
 884
 885 static void
 886 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 887                         struct nfs_page *req)
 888 {
 889         struct nfs4_ff_layout_mirror *mirror;
 890         struct nfs_pgio_mirror *pgm;
 891         struct nfs4_pnfs_ds *ds;
 892         u32 i;
 893
 894 retry:
 895         ff_layout_pg_check_layout(pgio, req);
 896         if (!pgio->pg_lseg) {
 897                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 898                                                    nfs_req_openctx(req),
 899                                                    req_offset(req),
 900                                                    req->wb_bytes,
 901                                                    IOMODE_RW,
 902                                                    false,
 903                                                    GFP_NOFS);
 904                 if (IS_ERR(pgio->pg_lseg)) {
 905                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 906                         pgio->pg_lseg = NULL;
 907                         return;
 908                 }
 909         }
 910         /* If no lseg, fall back to write through mds */
 911         if (pgio->pg_lseg == NULL)
 912                 goto out_mds;
 913
 914         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 915         if (pgio->pg_mirror_count != FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg))
 916                 goto out_eagain;
 917
 918         for (i = 0; i < pgio->pg_mirror_count; i++) {
 919                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 920                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
 921                 if (!ds) {
 922                         if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 923                                 goto out_mds;
 924                         pnfs_generic_pg_cleanup(pgio);
 925                         /* Sleep for 1 second before retrying */
 926                         ssleep(1);
 927                         goto retry;
 928                 }
 929                 pgm = &pgio->pg_mirrors[i];
 930                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 931         }
 932
 933         if (NFS_SERVER(pgio->pg_inode)->flags &
 934                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 935                 pgio->pg_maxretrans = io_maxretrans;
 936         return;
 937 out_eagain:
 938         pnfs_generic_pg_cleanup(pgio);
 939         pgio->pg_error = -EAGAIN;
 940         return;
 941 out_mds:
 942         trace_pnfs_mds_fallback_pg_init_write(pgio->pg_inode,
 943                         0, NFS4_MAX_UINT64, IOMODE_RW,
 944                         NFS_I(pgio->pg_inode)->layout,
 945                         pgio->pg_lseg);
 946         pgio->pg_maxretrans = 0;
 947         nfs_pageio_reset_write_mds(pgio);
 948         pgio->pg_error = -EAGAIN;
 949 }
 950
 951 static unsigned int
 952 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
 953                                     struct nfs_page *req)
 954 {
 955         if (!pgio->pg_lseg) {
 956                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 957                                                    nfs_req_openctx(req),
 958                                                    req_offset(req),
 959                                                    req->wb_bytes,
 960                                                    IOMODE_RW,
 961                                                    false,
 962                                                    GFP_NOFS);
 963                 if (IS_ERR(pgio->pg_lseg)) {
 964                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 965                         pgio->pg_lseg = NULL;
 966                         goto out;
 967                 }
 968         }
 969         if (pgio->pg_lseg)
 970                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
 971
 972         trace_pnfs_mds_fallback_pg_get_mirror_count(pgio->pg_inode,
 973                         0, NFS4_MAX_UINT64, IOMODE_RW,
 974                         NFS_I(pgio->pg_inode)->layout,
 975                         pgio->pg_lseg);
 976         /* no lseg means that pnfs is not in use, so no mirroring here */
 977         nfs_pageio_reset_write_mds(pgio);
 978 out:
 979         return 1;
 980 }
 981
 982 static u32
 983 ff_layout_pg_set_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 984 {
 985         u32 old = desc->pg_mirror_idx;
 986
 987         desc->pg_mirror_idx = idx;
 988         return old;
 989 }
 990
 991 static struct nfs_pgio_mirror *
 992 ff_layout_pg_get_mirror_write(struct nfs_pageio_descriptor *desc, u32 idx)
 993 {
 994         return &desc->pg_mirrors[idx];
 995 }
 996
 997 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
 998         .pg_init = ff_layout_pg_init_read,
 999         .pg_test = pnfs_generic_pg_test,
1000         .pg_doio = pnfs_generic_pg_readpages,
1001         .pg_cleanup = pnfs_generic_pg_cleanup,
1002 };
1003
1004 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
1005         .pg_init = ff_layout_pg_init_write,
1006         .pg_test = pnfs_generic_pg_test,
1007         .pg_doio = pnfs_generic_pg_writepages,
1008         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1009         .pg_cleanup = pnfs_generic_pg_cleanup,
1010         .pg_get_mirror = ff_layout_pg_get_mirror_write,
1011         .pg_set_mirror = ff_layout_pg_set_mirror_write,
1012 };
1013
1014 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1015 {
1016         struct rpc_task *task = &hdr->task;
1017
1018         pnfs_layoutcommit_inode(hdr->inode, false);
1019
1020         if (retry_pnfs) {
1021                 dprintk("%s Reset task %5u for i/o through pNFS "
1022                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1023                         hdr->task.tk_pid,
1024                         hdr->inode->i_sb->s_id,
1025                         (unsigned long long)NFS_FILEID(hdr->inode),
1026                         hdr->args.count,
1027                         (unsigned long long)hdr->args.offset);
1028
1029                 hdr->completion_ops->reschedule_io(hdr);
1030                 return;
1031         }
1032
1033         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1034                 dprintk("%s Reset task %5u for i/o through MDS "
1035                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1036                         hdr->task.tk_pid,
1037                         hdr->inode->i_sb->s_id,
1038                         (unsigned long long)NFS_FILEID(hdr->inode),
1039                         hdr->args.count,
1040                         (unsigned long long)hdr->args.offset);
1041
1042                 trace_pnfs_mds_fallback_write_done(hdr->inode,
1043                                 hdr->args.offset, hdr->args.count,
1044                                 IOMODE_RW, NFS_I(hdr->inode)->layout,
1045                                 hdr->lseg);
1046                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1047         }
1048 }
1049
1050 static void ff_layout_resend_pnfs_read(struct nfs_pgio_header *hdr)
1051 {
1052         u32 idx = hdr->pgio_mirror_idx + 1;
1053         u32 new_idx = 0;
1054
1055         if (ff_layout_choose_any_ds_for_read(hdr->lseg, idx, &new_idx))
1056                 ff_layout_send_layouterror(hdr->lseg);
1057         else
1058                 pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1059         pnfs_read_resend_pnfs(hdr, new_idx);
1060 }
1061
1062 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1063 {
1064         struct rpc_task *task = &hdr->task;
1065
1066         pnfs_layoutcommit_inode(hdr->inode, false);
1067         pnfs_error_mark_layout_for_return(hdr->inode, hdr->lseg);
1068
1069         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1070                 dprintk("%s Reset task %5u for i/o through MDS "
1071                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1072                         hdr->task.tk_pid,
1073                         hdr->inode->i_sb->s_id,
1074                         (unsigned long long)NFS_FILEID(hdr->inode),
1075                         hdr->args.count,
1076                         (unsigned long long)hdr->args.offset);
1077
1078                 trace_pnfs_mds_fallback_read_done(hdr->inode,
1079                                 hdr->args.offset, hdr->args.count,
1080                                 IOMODE_READ, NFS_I(hdr->inode)->layout,
1081                                 hdr->lseg);
1082                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1083         }
1084 }
1085
1086 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1087                                            struct nfs4_state *state,
1088                                            struct nfs_client *clp,
1089                                            struct pnfs_layout_segment *lseg,
1090                                            u32 idx)
1091 {
1092         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1093         struct inode *inode = lo->plh_inode;
1094         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1095         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1096
1097         switch (task->tk_status) {
1098         case -NFS4ERR_BADSESSION:
1099         case -NFS4ERR_BADSLOT:
1100         case -NFS4ERR_BAD_HIGH_SLOT:
1101         case -NFS4ERR_DEADSESSION:
1102         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1103         case -NFS4ERR_SEQ_FALSE_RETRY:
1104         case -NFS4ERR_SEQ_MISORDERED:
1105                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1106                         "flags 0x%x\n", __func__, task->tk_status,
1107                         clp->cl_exchange_flags);
1108                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1109                 break;
1110         case -NFS4ERR_DELAY:
1111         case -NFS4ERR_GRACE:
1112                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1113                 break;
1114         case -NFS4ERR_RETRY_UNCACHED_REP:
1115                 break;
1116         /* Invalidate Layout errors */
1117         case -NFS4ERR_PNFS_NO_LAYOUT:
1118         case -ESTALE:           /* mapped NFS4ERR_STALE */
1119         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1120         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1121         case -NFS4ERR_FHEXPIRED:
1122         case -NFS4ERR_WRONG_TYPE:
1123                 dprintk("%s Invalid layout error %d\n", __func__,
1124                         task->tk_status);
1125                 /*
1126                  * Destroy layout so new i/o will get a new layout.
1127                  * Layout will not be destroyed until all current lseg
1128                  * references are put. Mark layout as invalid to resend failed
1129                  * i/o and all i/o waiting on the slot table to the MDS until
1130                  * layout is destroyed and a new valid layout is obtained.
1131                  */
1132                 pnfs_destroy_layout(NFS_I(inode));
1133                 rpc_wake_up(&tbl->slot_tbl_waitq);
1134                 goto reset;
1135         /* RPC connection errors */
1136         case -ECONNREFUSED:
1137         case -EHOSTDOWN:
1138         case -EHOSTUNREACH:
1139         case -ENETUNREACH:
1140         case -EIO:
1141         case -ETIMEDOUT:
1142         case -EPIPE:
1143                 dprintk("%s DS connection error %d\n", __func__,
1144                         task->tk_status);
1145                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1146                                 &devid->deviceid);
1147                 rpc_wake_up(&tbl->slot_tbl_waitq);
1148                 fallthrough;
1149         default:
1150                 if (ff_layout_avoid_mds_available_ds(lseg))
1151                         return -NFS4ERR_RESET_TO_PNFS;
1152 reset:
1153                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1154                         task->tk_status);
1155                 return -NFS4ERR_RESET_TO_MDS;
1156         }
1157         task->tk_status = 0;
1158         return -EAGAIN;
1159 }
1160
1161 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1162 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1163                                            struct pnfs_layout_segment *lseg,
1164                                            u32 idx)
1165 {
1166         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1167
1168         switch (task->tk_status) {
1169         /* File access problems. Don't mark the device as unavailable */
1170         case -EACCES:
1171         case -ESTALE:
1172         case -EISDIR:
1173         case -EBADHANDLE:
1174         case -ELOOP:
1175         case -ENOSPC:
1176                 break;
1177         case -EJUKEBOX:
1178                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1179                 goto out_retry;
1180         default:
1181                 dprintk("%s DS connection error %d\n", __func__,
1182                         task->tk_status);
1183                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1184                                 &devid->deviceid);
1185         }
1186         /* FIXME: Need to prevent infinite looping here. */
1187         return -NFS4ERR_RESET_TO_PNFS;
1188 out_retry:
1189         task->tk_status = 0;
1190         rpc_restart_call_prepare(task);
1191         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1192         return -EAGAIN;
1193 }
1194
1195 static int ff_layout_async_handle_error(struct rpc_task *task,
1196                                         struct nfs4_state *state,
1197                                         struct nfs_client *clp,
1198                                         struct pnfs_layout_segment *lseg,
1199                                         u32 idx)
1200 {
1201         int vers = clp->cl_nfs_mod->rpc_vers->number;
1202
1203         if (task->tk_status >= 0) {
1204                 ff_layout_mark_ds_reachable(lseg, idx);
1205                 return 0;
1206         }
1207
1208         /* Handle the case of an invalid layout segment */
1209         if (!pnfs_is_valid_lseg(lseg))
1210                 return -NFS4ERR_RESET_TO_PNFS;
1211
1212         switch (vers) {
1213         case 3:
1214                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1215         case 4:
1216                 return ff_layout_async_handle_error_v4(task, state, clp,
1217                                                        lseg, idx);
1218         default:
1219                 /* should never happen */
1220                 WARN_ON_ONCE(1);
1221                 return 0;
1222         }
1223 }
1224
1225 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1226                                         u32 idx, u64 offset, u64 length,
1227                                         u32 *op_status, int opnum, int error)
1228 {
1229         struct nfs4_ff_layout_mirror *mirror;
1230         u32 status = *op_status;
1231         int err;
1232
1233         if (status == 0) {
1234                 switch (error) {
1235                 case -ETIMEDOUT:
1236                 case -EPFNOSUPPORT:
1237                 case -EPROTONOSUPPORT:
1238                 case -EOPNOTSUPP:
1239                 case -ECONNREFUSED:
1240                 case -ECONNRESET:
1241                 case -EHOSTDOWN:
1242                 case -EHOSTUNREACH:
1243                 case -ENETUNREACH:
1244                 case -EADDRINUSE:
1245                 case -ENOBUFS:
1246                 case -EPIPE:
1247                 case -EPERM:
1248                         *op_status = status = NFS4ERR_NXIO;
1249                         break;
1250                 case -EACCES:
1251                         *op_status = status = NFS4ERR_ACCESS;
1252                         break;
1253                 default:
1254                         return;
1255                 }
1256         }
1257
1258         mirror = FF_LAYOUT_COMP(lseg, idx);
1259         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1260                                        mirror, offset, length, status, opnum,
1261                                        GFP_NOIO);
1262
1263         switch (status) {
1264         case NFS4ERR_DELAY:
1265         case NFS4ERR_GRACE:
1266                 break;
1267         case NFS4ERR_NXIO:
1268                 ff_layout_mark_ds_unreachable(lseg, idx);
1269                 /*
1270                  * Don't return the layout if this is a read and we still
1271                  * have layouts to try
1272                  */
1273                 if (opnum == OP_READ)
1274                         break;
1275                 fallthrough;
1276         default:
1277                 pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode,
1278                                                   lseg);
1279         }
1280
1281         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1282 }
1283
1284 /* NFS_PROTO call done callback routines */
1285 static int ff_layout_read_done_cb(struct rpc_task *task,
1286                                 struct nfs_pgio_header *hdr)
1287 {
1288         int err;
1289
1290         if (task->tk_status < 0) {
1291                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1292                                             hdr->args.offset, hdr->args.count,
1293                                             &hdr->res.op_status, OP_READ,
1294                                             task->tk_status);
1295                 trace_ff_layout_read_error(hdr);
1296         }
1297
1298         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1299                                            hdr->ds_clp, hdr->lseg,
1300                                            hdr->pgio_mirror_idx);
1301
1302         trace_nfs4_pnfs_read(hdr, err);
1303         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1304         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1305         switch (err) {
1306         case -NFS4ERR_RESET_TO_PNFS:
1307                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1308                 return task->tk_status;
1309         case -NFS4ERR_RESET_TO_MDS:
1310                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1311                 return task->tk_status;
1312         case -EAGAIN:
1313                 goto out_eagain;
1314         }
1315
1316         return 0;
1317 out_eagain:
1318         rpc_restart_call_prepare(task);
1319         return -EAGAIN;
1320 }
1321
1322 static bool
1323 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1324 {
1325         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1326 }
1327
1328 /*
1329  * We reference the rpc_cred of the first WRITE that triggers the need for
1330  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1331  * rfc5661 is not clear about which credential should be used.
1332  *
1333  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1334  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1335  * we always send layoutcommit after DS writes.
1336  */
1337 static void
1338 ff_layout_set_layoutcommit(struct inode *inode,
1339                 struct pnfs_layout_segment *lseg,
1340                 loff_t end_offset)
1341 {
1342         if (!ff_layout_need_layoutcommit(lseg))
1343                 return;
1344
1345         pnfs_set_layoutcommit(inode, lseg, end_offset);
1346         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1347                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1348 }
1349
1350 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1351                 struct nfs_pgio_header *hdr)
1352 {
1353         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1354                 return;
1355         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1356                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1357                         hdr->args.count,
1358                         task->tk_start);
1359 }
1360
1361 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1362                 struct nfs_pgio_header *hdr)
1363 {
1364         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1365                 return;
1366         nfs4_ff_layout_stat_io_end_read(task,
1367                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1368                         hdr->args.count,
1369                         hdr->res.count);
1370         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1371 }
1372
1373 static int ff_layout_read_prepare_common(struct rpc_task *task,
1374                                          struct nfs_pgio_header *hdr)
1375 {
1376         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1377                 rpc_exit(task, -EIO);
1378                 return -EIO;
1379         }
1380
1381         ff_layout_read_record_layoutstats_start(task, hdr);
1382         return 0;
1383 }
1384
1385 /*
1386  * Call ops for the async read/write cases
1387  * In the case of dense layouts, the offset needs to be reset to its
1388  * original value.
1389  */
1390 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1391 {
1392         struct nfs_pgio_header *hdr = data;
1393
1394         if (ff_layout_read_prepare_common(task, hdr))
1395                 return;
1396
1397         rpc_call_start(task);
1398 }
1399
1400 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1401 {
1402         struct nfs_pgio_header *hdr = data;
1403
1404         if (nfs4_setup_sequence(hdr->ds_clp,
1405                                 &hdr->args.seq_args,
1406                                 &hdr->res.seq_res,
1407                                 task))
1408                 return;
1409
1410         ff_layout_read_prepare_common(task, hdr);
1411 }
1412
1413 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1414 {
1415         struct nfs_pgio_header *hdr = data;
1416
1417         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1418
1419         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1420             task->tk_status == 0) {
1421                 nfs4_sequence_done(task, &hdr->res.seq_res);
1422                 return;
1423         }
1424
1425         /* Note this may cause RPC to be resent */
1426         hdr->mds_ops->rpc_call_done(task, hdr);
1427 }
1428
1429 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1430 {
1431         struct nfs_pgio_header *hdr = data;
1432
1433         ff_layout_read_record_layoutstats_done(task, hdr);
1434         rpc_count_iostats_metrics(task,
1435             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1436 }
1437
1438 static void ff_layout_read_release(void *data)
1439 {
1440         struct nfs_pgio_header *hdr = data;
1441
1442         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1443         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags))
1444                 ff_layout_resend_pnfs_read(hdr);
1445         else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1446                 ff_layout_reset_read(hdr);
1447         pnfs_generic_rw_release(data);
1448 }
1449
1450
1451 static int ff_layout_write_done_cb(struct rpc_task *task,
1452                                 struct nfs_pgio_header *hdr)
1453 {
1454         loff_t end_offs = 0;
1455         int err;
1456
1457         if (task->tk_status < 0) {
1458                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1459                                             hdr->args.offset, hdr->args.count,
1460                                             &hdr->res.op_status, OP_WRITE,
1461                                             task->tk_status);
1462                 trace_ff_layout_write_error(hdr);
1463         }
1464
1465         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1466                                            hdr->ds_clp, hdr->lseg,
1467                                            hdr->pgio_mirror_idx);
1468
1469         trace_nfs4_pnfs_write(hdr, err);
1470         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1471         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1472         switch (err) {
1473         case -NFS4ERR_RESET_TO_PNFS:
1474                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1475                 return task->tk_status;
1476         case -NFS4ERR_RESET_TO_MDS:
1477                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1478                 return task->tk_status;
1479         case -EAGAIN:
1480                 return -EAGAIN;
1481         }
1482
1483         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1484             hdr->res.verf->committed == NFS_DATA_SYNC)
1485                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1486
1487         /* Note: if the write is unstable, don't set end_offs until commit */
1488         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1489
1490         /* zero out fattr since we don't care DS attr at all */
1491         hdr->fattr.valid = 0;
1492         if (task->tk_status >= 0)
1493                 nfs_writeback_update_inode(hdr);
1494
1495         return 0;
1496 }
1497
1498 static int ff_layout_commit_done_cb(struct rpc_task *task,
1499                                      struct nfs_commit_data *data)
1500 {
1501         int err;
1502
1503         if (task->tk_status < 0) {
1504                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1505                                             data->args.offset, data->args.count,
1506                                             &data->res.op_status, OP_COMMIT,
1507                                             task->tk_status);
1508                 trace_ff_layout_commit_error(data);
1509         }
1510
1511         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1512                                            data->lseg, data->ds_commit_index);
1513
1514         trace_nfs4_pnfs_commit_ds(data, err);
1515         switch (err) {
1516         case -NFS4ERR_RESET_TO_PNFS:
1517                 pnfs_generic_prepare_to_resend_writes(data);
1518                 return -EAGAIN;
1519         case -NFS4ERR_RESET_TO_MDS:
1520                 pnfs_generic_prepare_to_resend_writes(data);
1521                 return -EAGAIN;
1522         case -EAGAIN:
1523                 rpc_restart_call_prepare(task);
1524                 return -EAGAIN;
1525         }
1526
1527         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1528
1529         return 0;
1530 }
1531
1532 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1533                 struct nfs_pgio_header *hdr)
1534 {
1535         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1536                 return;
1537         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1538                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1539                         hdr->args.count,
1540                         task->tk_start);
1541 }
1542
1543 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1544                 struct nfs_pgio_header *hdr)
1545 {
1546         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1547                 return;
1548         nfs4_ff_layout_stat_io_end_write(task,
1549                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1550                         hdr->args.count, hdr->res.count,
1551                         hdr->res.verf->committed);
1552         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1553 }
1554
1555 static int ff_layout_write_prepare_common(struct rpc_task *task,
1556                                           struct nfs_pgio_header *hdr)
1557 {
1558         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1559                 rpc_exit(task, -EIO);
1560                 return -EIO;
1561         }
1562
1563         ff_layout_write_record_layoutstats_start(task, hdr);
1564         return 0;
1565 }
1566
1567 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1568 {
1569         struct nfs_pgio_header *hdr = data;
1570
1571         if (ff_layout_write_prepare_common(task, hdr))
1572                 return;
1573
1574         rpc_call_start(task);
1575 }
1576
1577 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1578 {
1579         struct nfs_pgio_header *hdr = data;
1580
1581         if (nfs4_setup_sequence(hdr->ds_clp,
1582                                 &hdr->args.seq_args,
1583                                 &hdr->res.seq_res,
1584                                 task))
1585                 return;
1586
1587         ff_layout_write_prepare_common(task, hdr);
1588 }
1589
1590 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1591 {
1592         struct nfs_pgio_header *hdr = data;
1593
1594         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1595             task->tk_status == 0) {
1596                 nfs4_sequence_done(task, &hdr->res.seq_res);
1597                 return;
1598         }
1599
1600         /* Note this may cause RPC to be resent */
1601         hdr->mds_ops->rpc_call_done(task, hdr);
1602 }
1603
1604 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1605 {
1606         struct nfs_pgio_header *hdr = data;
1607
1608         ff_layout_write_record_layoutstats_done(task, hdr);
1609         rpc_count_iostats_metrics(task,
1610             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1611 }
1612
1613 static void ff_layout_write_release(void *data)
1614 {
1615         struct nfs_pgio_header *hdr = data;
1616
1617         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1618         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1619                 ff_layout_send_layouterror(hdr->lseg);
1620                 ff_layout_reset_write(hdr, true);
1621         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1622                 ff_layout_reset_write(hdr, false);
1623         pnfs_generic_rw_release(data);
1624 }
1625
1626 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1627                 struct nfs_commit_data *cdata)
1628 {
1629         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1630                 return;
1631         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1632                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1633                         0, task->tk_start);
1634 }
1635
1636 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1637                 struct nfs_commit_data *cdata)
1638 {
1639         struct nfs_page *req;
1640         __u64 count = 0;
1641
1642         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1643                 return;
1644
1645         if (task->tk_status == 0) {
1646                 list_for_each_entry(req, &cdata->pages, wb_list)
1647                         count += req->wb_bytes;
1648         }
1649         nfs4_ff_layout_stat_io_end_write(task,
1650                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1651                         count, count, NFS_FILE_SYNC);
1652         set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1653 }
1654
1655 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1656                 struct nfs_commit_data *cdata)
1657 {
1658         ff_layout_commit_record_layoutstats_start(task, cdata);
1659 }
1660
1661 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1662 {
1663         ff_layout_commit_prepare_common(task, data);
1664         rpc_call_start(task);
1665 }
1666
1667 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1668 {
1669         struct nfs_commit_data *wdata = data;
1670
1671         if (nfs4_setup_sequence(wdata->ds_clp,
1672                                 &wdata->args.seq_args,
1673                                 &wdata->res.seq_res,
1674                                 task))
1675                 return;
1676         ff_layout_commit_prepare_common(task, data);
1677 }
1678
1679 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1680 {
1681         pnfs_generic_write_commit_done(task, data);
1682 }
1683
1684 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1685 {
1686         struct nfs_commit_data *cdata = data;
1687
1688         ff_layout_commit_record_layoutstats_done(task, cdata);
1689         rpc_count_iostats_metrics(task,
1690             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1691 }
1692
1693 static void ff_layout_commit_release(void *data)
1694 {
1695         struct nfs_commit_data *cdata = data;
1696
1697         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1698         pnfs_generic_commit_release(data);
1699 }
1700
1701 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1702         .rpc_call_prepare = ff_layout_read_prepare_v3,
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_read_call_ops_v4 = {
1709         .rpc_call_prepare = ff_layout_read_prepare_v4,
1710         .rpc_call_done = ff_layout_read_call_done,
1711         .rpc_count_stats = ff_layout_read_count_stats,
1712         .rpc_release = ff_layout_read_release,
1713 };
1714
1715 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1716         .rpc_call_prepare = ff_layout_write_prepare_v3,
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_write_call_ops_v4 = {
1723         .rpc_call_prepare = ff_layout_write_prepare_v4,
1724         .rpc_call_done = ff_layout_write_call_done,
1725         .rpc_count_stats = ff_layout_write_count_stats,
1726         .rpc_release = ff_layout_write_release,
1727 };
1728
1729 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1730         .rpc_call_prepare = ff_layout_commit_prepare_v3,
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 const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1737         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1738         .rpc_call_done = ff_layout_commit_done,
1739         .rpc_count_stats = ff_layout_commit_count_stats,
1740         .rpc_release = ff_layout_commit_release,
1741 };
1742
1743 static enum pnfs_try_status
1744 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1745 {
1746         struct pnfs_layout_segment *lseg = hdr->lseg;
1747         struct nfs4_pnfs_ds *ds;
1748         struct rpc_clnt *ds_clnt;
1749         struct nfs4_ff_layout_mirror *mirror;
1750         const struct cred *ds_cred;
1751         loff_t offset = hdr->args.offset;
1752         u32 idx = hdr->pgio_mirror_idx;
1753         int vers;
1754         struct nfs_fh *fh;
1755
1756         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1757                 __func__, hdr->inode->i_ino,
1758                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1759
1760         mirror = FF_LAYOUT_COMP(lseg, idx);
1761         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
1762         if (!ds)
1763                 goto out_failed;
1764
1765         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1766                                                    hdr->inode);
1767         if (IS_ERR(ds_clnt))
1768                 goto out_failed;
1769
1770         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1771         if (!ds_cred)
1772                 goto out_failed;
1773
1774         vers = nfs4_ff_layout_ds_version(mirror);
1775
1776         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1777                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1778
1779         hdr->pgio_done_cb = ff_layout_read_done_cb;
1780         refcount_inc(&ds->ds_clp->cl_count);
1781         hdr->ds_clp = ds->ds_clp;
1782         fh = nfs4_ff_layout_select_ds_fh(mirror);
1783         if (fh)
1784                 hdr->args.fh = fh;
1785
1786         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1787
1788         /*
1789          * Note that if we ever decide to split across DSes,
1790          * then we may need to handle dense-like offsets.
1791          */
1792         hdr->args.offset = offset;
1793         hdr->mds_offset = offset;
1794
1795         /* Perform an asynchronous read to ds */
1796         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1797                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1798                                       &ff_layout_read_call_ops_v4,
1799                           0, RPC_TASK_SOFTCONN);
1800         put_cred(ds_cred);
1801         return PNFS_ATTEMPTED;
1802
1803 out_failed:
1804         if (ff_layout_avoid_mds_available_ds(lseg))
1805                 return PNFS_TRY_AGAIN;
1806         trace_pnfs_mds_fallback_read_pagelist(hdr->inode,
1807                         hdr->args.offset, hdr->args.count,
1808                         IOMODE_READ, NFS_I(hdr->inode)->layout, lseg);
1809         return PNFS_NOT_ATTEMPTED;
1810 }
1811
1812 /* Perform async writes. */
1813 static enum pnfs_try_status
1814 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1815 {
1816         struct pnfs_layout_segment *lseg = hdr->lseg;
1817         struct nfs4_pnfs_ds *ds;
1818         struct rpc_clnt *ds_clnt;
1819         struct nfs4_ff_layout_mirror *mirror;
1820         const struct cred *ds_cred;
1821         loff_t offset = hdr->args.offset;
1822         int vers;
1823         struct nfs_fh *fh;
1824         u32 idx = hdr->pgio_mirror_idx;
1825
1826         mirror = FF_LAYOUT_COMP(lseg, idx);
1827         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1828         if (!ds)
1829                 goto out_failed;
1830
1831         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1832                                                    hdr->inode);
1833         if (IS_ERR(ds_clnt))
1834                 goto out_failed;
1835
1836         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1837         if (!ds_cred)
1838                 goto out_failed;
1839
1840         vers = nfs4_ff_layout_ds_version(mirror);
1841
1842         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1843                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1844                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1845                 vers);
1846
1847         hdr->pgio_done_cb = ff_layout_write_done_cb;
1848         refcount_inc(&ds->ds_clp->cl_count);
1849         hdr->ds_clp = ds->ds_clp;
1850         hdr->ds_commit_idx = idx;
1851         fh = nfs4_ff_layout_select_ds_fh(mirror);
1852         if (fh)
1853                 hdr->args.fh = fh;
1854
1855         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1856
1857         /*
1858          * Note that if we ever decide to split across DSes,
1859          * then we may need to handle dense-like offsets.
1860          */
1861         hdr->args.offset = offset;
1862
1863         /* Perform an asynchronous write */
1864         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1865                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1866                                       &ff_layout_write_call_ops_v4,
1867                           sync, RPC_TASK_SOFTCONN);
1868         put_cred(ds_cred);
1869         return PNFS_ATTEMPTED;
1870
1871 out_failed:
1872         if (ff_layout_avoid_mds_available_ds(lseg))
1873                 return PNFS_TRY_AGAIN;
1874         trace_pnfs_mds_fallback_write_pagelist(hdr->inode,
1875                         hdr->args.offset, hdr->args.count,
1876                         IOMODE_RW, NFS_I(hdr->inode)->layout, lseg);
1877         return PNFS_NOT_ATTEMPTED;
1878 }
1879
1880 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1881 {
1882         return i;
1883 }
1884
1885 static struct nfs_fh *
1886 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1887 {
1888         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1889
1890         /* FIXME: Assume that there is only one NFS version available
1891          * for the DS.
1892          */
1893         return &flseg->mirror_array[i]->fh_versions[0];
1894 }
1895
1896 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1897 {
1898         struct pnfs_layout_segment *lseg = data->lseg;
1899         struct nfs4_pnfs_ds *ds;
1900         struct rpc_clnt *ds_clnt;
1901         struct nfs4_ff_layout_mirror *mirror;
1902         const struct cred *ds_cred;
1903         u32 idx;
1904         int vers, ret;
1905         struct nfs_fh *fh;
1906
1907         if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1908             test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1909                 goto out_err;
1910
1911         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1912         mirror = FF_LAYOUT_COMP(lseg, idx);
1913         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1914         if (!ds)
1915                 goto out_err;
1916
1917         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1918                                                    data->inode);
1919         if (IS_ERR(ds_clnt))
1920                 goto out_err;
1921
1922         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
1923         if (!ds_cred)
1924                 goto out_err;
1925
1926         vers = nfs4_ff_layout_ds_version(mirror);
1927
1928         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1929                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1930                 vers);
1931         data->commit_done_cb = ff_layout_commit_done_cb;
1932         data->cred = ds_cred;
1933         refcount_inc(&ds->ds_clp->cl_count);
1934         data->ds_clp = ds->ds_clp;
1935         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1936         if (fh)
1937                 data->args.fh = fh;
1938
1939         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1940                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1941                                                &ff_layout_commit_call_ops_v4,
1942                                    how, RPC_TASK_SOFTCONN);
1943         put_cred(ds_cred);
1944         return ret;
1945 out_err:
1946         pnfs_generic_prepare_to_resend_writes(data);
1947         pnfs_generic_commit_release(data);
1948         return -EAGAIN;
1949 }
1950
1951 static int
1952 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1953                            int how, struct nfs_commit_info *cinfo)
1954 {
1955         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1956                                             ff_layout_initiate_commit);
1957 }
1958
1959 static struct pnfs_ds_commit_info *
1960 ff_layout_get_ds_info(struct inode *inode)
1961 {
1962         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1963
1964         if (layout == NULL)
1965                 return NULL;
1966
1967         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1968 }
1969
1970 static void
1971 ff_layout_setup_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
1972                 struct pnfs_layout_segment *lseg)
1973 {
1974         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1975         struct inode *inode = lseg->pls_layout->plh_inode;
1976         struct pnfs_commit_array *array, *new;
1977
1978         new = pnfs_alloc_commit_array(flseg->mirror_array_cnt, GFP_NOIO);
1979         if (new) {
1980                 spin_lock(&inode->i_lock);
1981                 array = pnfs_add_commit_array(fl_cinfo, new, lseg);
1982                 spin_unlock(&inode->i_lock);
1983                 if (array != new)
1984                         pnfs_free_commit_array(new);
1985         }
1986 }
1987
1988 static void
1989 ff_layout_release_ds_info(struct pnfs_ds_commit_info *fl_cinfo,
1990                 struct inode *inode)
1991 {
1992         spin_lock(&inode->i_lock);
1993         pnfs_generic_ds_cinfo_destroy(fl_cinfo);
1994         spin_unlock(&inode->i_lock);
1995 }
1996
1997 static void
1998 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1999 {
2000         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
2001                                                   id_node));
2002 }
2003
2004 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
2005                                   const struct nfs4_layoutreturn_args *args,
2006                                   const struct nfs4_flexfile_layoutreturn_args *ff_args)
2007 {
2008         __be32 *start;
2009
2010         start = xdr_reserve_space(xdr, 4);
2011         if (unlikely(!start))
2012                 return -E2BIG;
2013
2014         *start = cpu_to_be32(ff_args->num_errors);
2015         /* This assume we always return _ALL_ layouts */
2016         return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
2017 }
2018
2019 static void
2020 encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
2021 {
2022         WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
2023 }
2024
2025 static void
2026 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
2027                             const nfs4_stateid *stateid,
2028                             const struct nfs42_layoutstat_devinfo *devinfo)
2029 {
2030         __be32 *p;
2031
2032         p = xdr_reserve_space(xdr, 8 + 8);
2033         p = xdr_encode_hyper(p, devinfo->offset);
2034         p = xdr_encode_hyper(p, devinfo->length);
2035         encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
2036         p = xdr_reserve_space(xdr, 4*8);
2037         p = xdr_encode_hyper(p, devinfo->read_count);
2038         p = xdr_encode_hyper(p, devinfo->read_bytes);
2039         p = xdr_encode_hyper(p, devinfo->write_count);
2040         p = xdr_encode_hyper(p, devinfo->write_bytes);
2041         encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
2042 }
2043
2044 static void
2045 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
2046                             const nfs4_stateid *stateid,
2047                             const struct nfs42_layoutstat_devinfo *devinfo)
2048 {
2049         ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
2050         ff_layout_encode_ff_layoutupdate(xdr, devinfo,
2051                         devinfo->ld_private.data);
2052 }
2053
2054 /* report nothing for now */
2055 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
2056                 const struct nfs4_layoutreturn_args *args,
2057                 struct nfs4_flexfile_layoutreturn_args *ff_args)
2058 {
2059         __be32 *p;
2060         int i;
2061
2062         p = xdr_reserve_space(xdr, 4);
2063         *p = cpu_to_be32(ff_args->num_dev);
2064         for (i = 0; i < ff_args->num_dev; i++)
2065                 ff_layout_encode_ff_iostat(xdr,
2066                                 &args->layout->plh_stateid,
2067                                 &ff_args->devinfo[i]);
2068 }
2069
2070 static void
2071 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
2072                 unsigned int num_entries)
2073 {
2074         unsigned int i;
2075
2076         for (i = 0; i < num_entries; i++) {
2077                 if (!devinfo[i].ld_private.ops)
2078                         continue;
2079                 if (!devinfo[i].ld_private.ops->free)
2080                         continue;
2081                 devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2082         }
2083 }
2084
2085 static struct nfs4_deviceid_node *
2086 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2087                               struct pnfs_device *pdev, gfp_t gfp_flags)
2088 {
2089         struct nfs4_ff_layout_ds *dsaddr;
2090
2091         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2092         if (!dsaddr)
2093                 return NULL;
2094         return &dsaddr->id_node;
2095 }
2096
2097 static void
2098 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2099                 const void *voidargs,
2100                 const struct nfs4_xdr_opaque_data *ff_opaque)
2101 {
2102         const struct nfs4_layoutreturn_args *args = voidargs;
2103         struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2104         struct xdr_buf tmp_buf = {
2105                 .head = {
2106                         [0] = {
2107                                 .iov_base = page_address(ff_args->pages[0]),
2108                         },
2109                 },
2110                 .buflen = PAGE_SIZE,
2111         };
2112         struct xdr_stream tmp_xdr;
2113         __be32 *start;
2114
2115         dprintk("%s: Begin\n", __func__);
2116
2117         xdr_init_encode(&tmp_xdr, &tmp_buf, NULL, NULL);
2118
2119         ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2120         ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2121
2122         start = xdr_reserve_space(xdr, 4);
2123         *start = cpu_to_be32(tmp_buf.len);
2124         xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2125
2126         dprintk("%s: Return\n", __func__);
2127 }
2128
2129 static void
2130 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2131 {
2132         struct nfs4_flexfile_layoutreturn_args *ff_args;
2133
2134         if (!args->data)
2135                 return;
2136         ff_args = args->data;
2137         args->data = NULL;
2138
2139         ff_layout_free_ds_ioerr(&ff_args->errors);
2140         ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2141
2142         put_page(ff_args->pages[0]);
2143         kfree(ff_args);
2144 }
2145
2146 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2147         .encode = ff_layout_encode_layoutreturn,
2148         .free = ff_layout_free_layoutreturn,
2149 };
2150
2151 static int
2152 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2153 {
2154         struct nfs4_flexfile_layoutreturn_args *ff_args;
2155         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2156
2157         ff_args = kmalloc(sizeof(*ff_args), GFP_KERNEL);
2158         if (!ff_args)
2159                 goto out_nomem;
2160         ff_args->pages[0] = alloc_page(GFP_KERNEL);
2161         if (!ff_args->pages[0])
2162                 goto out_nomem_free;
2163
2164         INIT_LIST_HEAD(&ff_args->errors);
2165         ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2166                         &args->range, &ff_args->errors,
2167                         FF_LAYOUTRETURN_MAXERR);
2168
2169         spin_lock(&args->inode->i_lock);
2170         ff_args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2171                         &ff_args->devinfo[0], ARRAY_SIZE(ff_args->devinfo));
2172         spin_unlock(&args->inode->i_lock);
2173
2174         args->ld_private->ops = &layoutreturn_ops;
2175         args->ld_private->data = ff_args;
2176         return 0;
2177 out_nomem_free:
2178         kfree(ff_args);
2179 out_nomem:
2180         return -ENOMEM;
2181 }
2182
2183 #ifdef CONFIG_NFS_V4_2
2184 void
2185 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2186 {
2187         struct pnfs_layout_hdr *lo = lseg->pls_layout;
2188         struct nfs42_layout_error *errors;
2189         LIST_HEAD(head);
2190
2191         if (!nfs_server_capable(lo->plh_inode, NFS_CAP_LAYOUTERROR))
2192                 return;
2193         ff_layout_fetch_ds_ioerr(lo, &lseg->pls_range, &head, -1);
2194         if (list_empty(&head))
2195                 return;
2196
2197         errors = kmalloc_array(NFS42_LAYOUTERROR_MAX,
2198                         sizeof(*errors), GFP_NOFS);
2199         if (errors != NULL) {
2200                 const struct nfs4_ff_layout_ds_err *pos;
2201                 size_t n = 0;
2202
2203                 list_for_each_entry(pos, &head, list) {
2204                         errors[n].offset = pos->offset;
2205                         errors[n].length = pos->length;
2206                         nfs4_stateid_copy(&errors[n].stateid, &pos->stateid);
2207                         errors[n].errors[0].dev_id = pos->deviceid;
2208                         errors[n].errors[0].status = pos->status;
2209                         errors[n].errors[0].opnum = pos->opnum;
2210                         n++;
2211                         if (!list_is_last(&pos->list, &head) &&
2212                             n < NFS42_LAYOUTERROR_MAX)
2213                                 continue;
2214                         if (nfs42_proc_layouterror(lseg, errors, n) < 0)
2215                                 break;
2216                         n = 0;
2217                 }
2218                 kfree(errors);
2219         }
2220         ff_layout_free_ds_ioerr(&head);
2221 }
2222 #else
2223 void
2224 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2225 {
2226 }
2227 #endif
2228
2229 static int
2230 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2231 {
2232         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2233
2234         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2235 }
2236
2237 static size_t
2238 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2239                           const int buflen)
2240 {
2241         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2242         const struct in6_addr *addr = &sin6->sin6_addr;
2243
2244         /*
2245          * RFC 4291, Section 2.2.2
2246          *
2247          * Shorthanded ANY address
2248          */
2249         if (ipv6_addr_any(addr))
2250                 return snprintf(buf, buflen, "::");
2251
2252         /*
2253          * RFC 4291, Section 2.2.2
2254          *
2255          * Shorthanded loopback address
2256          */
2257         if (ipv6_addr_loopback(addr))
2258                 return snprintf(buf, buflen, "::1");
2259
2260         /*
2261          * RFC 4291, Section 2.2.3
2262          *
2263          * Special presentation address format for mapped v4
2264          * addresses.
2265          */
2266         if (ipv6_addr_v4mapped(addr))
2267                 return snprintf(buf, buflen, "::ffff:%pI4",
2268                                         &addr->s6_addr32[3]);
2269
2270         /*
2271          * RFC 4291, Section 2.2.1
2272          */
2273         return snprintf(buf, buflen, "%pI6c", addr);
2274 }
2275
2276 /* Derived from rpc_sockaddr2uaddr */
2277 static void
2278 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2279 {
2280         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2281         char portbuf[RPCBIND_MAXUADDRPLEN];
2282         char addrbuf[RPCBIND_MAXUADDRLEN];
2283         unsigned short port;
2284         int len, netid_len;
2285         __be32 *p;
2286
2287         switch (sap->sa_family) {
2288         case AF_INET:
2289                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2290                         return;
2291                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2292                 break;
2293         case AF_INET6:
2294                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2295                         return;
2296                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2297                 break;
2298         default:
2299                 WARN_ON_ONCE(1);
2300                 return;
2301         }
2302
2303         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2304         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2305
2306         netid_len = strlen(da->da_netid);
2307         p = xdr_reserve_space(xdr, 4 + netid_len);
2308         xdr_encode_opaque(p, da->da_netid, netid_len);
2309
2310         p = xdr_reserve_space(xdr, 4 + len);
2311         xdr_encode_opaque(p, addrbuf, len);
2312 }
2313
2314 static void
2315 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2316                          ktime_t t)
2317 {
2318         struct timespec64 ts;
2319         __be32 *p;
2320
2321         p = xdr_reserve_space(xdr, 12);
2322         ts = ktime_to_timespec64(t);
2323         p = xdr_encode_hyper(p, ts.tv_sec);
2324         *p++ = cpu_to_be32(ts.tv_nsec);
2325 }
2326
2327 static void
2328 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2329                             struct nfs4_ff_io_stat *stat)
2330 {
2331         __be32 *p;
2332
2333         p = xdr_reserve_space(xdr, 5 * 8);
2334         p = xdr_encode_hyper(p, stat->ops_requested);
2335         p = xdr_encode_hyper(p, stat->bytes_requested);
2336         p = xdr_encode_hyper(p, stat->ops_completed);
2337         p = xdr_encode_hyper(p, stat->bytes_completed);
2338         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2339         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2340         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2341 }
2342
2343 static void
2344 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2345                               const struct nfs42_layoutstat_devinfo *devinfo,
2346                               struct nfs4_ff_layout_mirror *mirror)
2347 {
2348         struct nfs4_pnfs_ds_addr *da;
2349         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2350         struct nfs_fh *fh = &mirror->fh_versions[0];
2351         __be32 *p;
2352
2353         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2354         dprintk("%s: DS %s: encoding address %s\n",
2355                 __func__, ds->ds_remotestr, da->da_remotestr);
2356         /* netaddr4 */
2357         ff_layout_encode_netaddr(xdr, da);
2358         /* nfs_fh4 */
2359         p = xdr_reserve_space(xdr, 4 + fh->size);
2360         xdr_encode_opaque(p, fh->data, fh->size);
2361         /* ff_io_latency4 read */
2362         spin_lock(&mirror->lock);
2363         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2364         /* ff_io_latency4 write */
2365         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2366         spin_unlock(&mirror->lock);
2367         /* nfstime4 */
2368         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2369         /* bool */
2370         p = xdr_reserve_space(xdr, 4);
2371         *p = cpu_to_be32(false);
2372 }
2373
2374 static void
2375 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2376                              const struct nfs4_xdr_opaque_data *opaque)
2377 {
2378         struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2379                         struct nfs42_layoutstat_devinfo, ld_private);
2380         __be32 *start;
2381
2382         /* layoutupdate length */
2383         start = xdr_reserve_space(xdr, 4);
2384         ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2385
2386         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2387 }
2388
2389 static void
2390 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2391 {
2392         struct nfs4_ff_layout_mirror *mirror = opaque->data;
2393
2394         ff_layout_put_mirror(mirror);
2395 }
2396
2397 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2398         .encode = ff_layout_encode_layoutstats,
2399         .free   = ff_layout_free_layoutstats,
2400 };
2401
2402 static int
2403 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2404                                struct nfs42_layoutstat_devinfo *devinfo,
2405                                int dev_limit)
2406 {
2407         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2408         struct nfs4_ff_layout_mirror *mirror;
2409         struct nfs4_deviceid_node *dev;
2410         int i = 0;
2411
2412         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2413                 if (i >= dev_limit)
2414                         break;
2415                 if (IS_ERR_OR_NULL(mirror->mirror_ds))
2416                         continue;
2417                 if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags))
2418                         continue;
2419                 /* mirror refcount put in cleanup_layoutstats */
2420                 if (!refcount_inc_not_zero(&mirror->ref))
2421                         continue;
2422                 dev = &mirror->mirror_ds->id_node;
2423                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2424                 devinfo->offset = 0;
2425                 devinfo->length = NFS4_MAX_UINT64;
2426                 spin_lock(&mirror->lock);
2427                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2428                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2429                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2430                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2431                 spin_unlock(&mirror->lock);
2432                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2433                 devinfo->ld_private.ops = &layoutstat_ops;
2434                 devinfo->ld_private.data = mirror;
2435
2436                 devinfo++;
2437                 i++;
2438         }
2439         return i;
2440 }
2441
2442 static int
2443 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2444 {
2445         struct nfs4_flexfile_layout *ff_layout;
2446         const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2447
2448         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2449         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
2450         if (!args->devinfo)
2451                 return -ENOMEM;
2452
2453         spin_lock(&args->inode->i_lock);
2454         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2455         args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2456                         &args->devinfo[0], dev_count);
2457         spin_unlock(&args->inode->i_lock);
2458         if (!args->num_dev) {
2459                 kfree(args->devinfo);
2460                 args->devinfo = NULL;
2461                 return -ENOENT;
2462         }
2463
2464         return 0;
2465 }
2466
2467 static int
2468 ff_layout_set_layoutdriver(struct nfs_server *server,
2469                 const struct nfs_fh *dummy)
2470 {
2471 #if IS_ENABLED(CONFIG_NFS_V4_2)
2472         server->caps |= NFS_CAP_LAYOUTSTATS;
2473 #endif
2474         return 0;
2475 }
2476
2477 static const struct pnfs_commit_ops ff_layout_commit_ops = {
2478         .setup_ds_info          = ff_layout_setup_ds_info,
2479         .release_ds_info        = ff_layout_release_ds_info,
2480         .mark_request_commit    = pnfs_layout_mark_request_commit,
2481         .clear_request_commit   = pnfs_generic_clear_request_commit,
2482         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2483         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2484         .commit_pagelist        = ff_layout_commit_pagelist,
2485 };
2486
2487 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2488         .id                     = LAYOUT_FLEX_FILES,
2489         .name                   = "LAYOUT_FLEX_FILES",
2490         .owner                  = THIS_MODULE,
2491         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
2492         .max_layoutget_response = 4096, /* 1 page or so... */
2493         .set_layoutdriver       = ff_layout_set_layoutdriver,
2494         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2495         .free_layout_hdr        = ff_layout_free_layout_hdr,
2496         .alloc_lseg             = ff_layout_alloc_lseg,
2497         .free_lseg              = ff_layout_free_lseg,
2498         .add_lseg               = ff_layout_add_lseg,
2499         .pg_read_ops            = &ff_layout_pg_read_ops,
2500         .pg_write_ops           = &ff_layout_pg_write_ops,
2501         .get_ds_info            = ff_layout_get_ds_info,
2502         .free_deviceid_node     = ff_layout_free_deviceid_node,
2503         .read_pagelist          = ff_layout_read_pagelist,
2504         .write_pagelist         = ff_layout_write_pagelist,
2505         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2506         .prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2507         .sync                   = pnfs_nfs_generic_sync,
2508         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2509 };
2510
2511 static int __init nfs4flexfilelayout_init(void)
2512 {
2513         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2514                __func__);
2515         return pnfs_register_layoutdriver(&flexfilelayout_type);
2516 }
2517
2518 static void __exit nfs4flexfilelayout_exit(void)
2519 {
2520         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2521                __func__);
2522         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2523 }
2524
2525 MODULE_ALIAS("nfs-layouttype4-4");
2526
2527 MODULE_LICENSE("GPL");
2528 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2529
2530 module_init(nfs4flexfilelayout_init);
2531 module_exit(nfs4flexfilelayout_exit);
2532
2533 module_param(io_maxretrans, ushort, 0644);
2534 MODULE_PARM_DESC(io_maxretrans, "The  number of times the NFSv4.1 client "
2535                         "retries an I/O request before returning an error. ");