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 void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
  36                 struct nfs_pgio_header *hdr);
  37 static int ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
  38                                struct nfs42_layoutstat_devinfo *devinfo,
  39                                int dev_limit);
  40 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
  41                               const struct nfs42_layoutstat_devinfo *devinfo,
  42                               struct nfs4_ff_layout_mirror *mirror);
  43
  44 static struct pnfs_layout_hdr *
  45 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  46 {
  47         struct nfs4_flexfile_layout *ffl;
  48
  49         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  50         if (ffl) {
  51                 INIT_LIST_HEAD(&ffl->error_list);
  52                 INIT_LIST_HEAD(&ffl->mirrors);
  53                 ffl->last_report_time = ktime_get();
  54                 return &ffl->generic_hdr;
  55         } else
  56                 return NULL;
  57 }
  58
  59 static void
  60 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  61 {
  62         struct nfs4_ff_layout_ds_err *err, *n;
  63
  64         list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  65                                  list) {
  66                 list_del(&err->list);
  67                 kfree(err);
  68         }
  69         kfree(FF_LAYOUT_FROM_HDR(lo));
  70 }
  71
  72 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  73 {
  74         __be32 *p;
  75
  76         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  77         if (unlikely(p == NULL))
  78                 return -ENOBUFS;
  79         stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  80         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  81         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  82                 p[0], p[1], p[2], p[3]);
  83         return 0;
  84 }
  85
  86 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  87 {
  88         __be32 *p;
  89
  90         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  91         if (unlikely(!p))
  92                 return -ENOBUFS;
  93         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  94         nfs4_print_deviceid(devid);
  95         return 0;
  96 }
  97
  98 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  99 {
 100         __be32 *p;
 101
 102         p = xdr_inline_decode(xdr, 4);
 103         if (unlikely(!p))
 104                 return -ENOBUFS;
 105         fh->size = be32_to_cpup(p++);
 106         if (fh->size > sizeof(struct nfs_fh)) {
 107                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
 108                        fh->size);
 109                 return -EOVERFLOW;
 110         }
 111         /* fh.data */
 112         p = xdr_inline_decode(xdr, fh->size);
 113         if (unlikely(!p))
 114                 return -ENOBUFS;
 115         memcpy(&fh->data, p, fh->size);
 116         dprintk("%s: fh len %d\n", __func__, fh->size);
 117
 118         return 0;
 119 }
 120
 121 /*
 122  * Currently only stringified uids and gids are accepted.
 123  * I.e., kerberos is not supported to the DSes, so no pricipals.
 124  *
 125  * That means that one common function will suffice, but when
 126  * principals are added, this should be split to accomodate
 127  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 128  */
 129 static int
 130 decode_name(struct xdr_stream *xdr, u32 *id)
 131 {
 132         __be32 *p;
 133         int len;
 134
 135         /* opaque_length(4)*/
 136         p = xdr_inline_decode(xdr, 4);
 137         if (unlikely(!p))
 138                 return -ENOBUFS;
 139         len = be32_to_cpup(p++);
 140         if (len < 0)
 141                 return -EINVAL;
 142
 143         dprintk("%s: len %u\n", __func__, len);
 144
 145         /* opaque body */
 146         p = xdr_inline_decode(xdr, len);
 147         if (unlikely(!p))
 148                 return -ENOBUFS;
 149
 150         if (!nfs_map_string_to_numeric((char *)p, len, id))
 151                 return -EINVAL;
 152
 153         return 0;
 154 }
 155
 156 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 157                 const struct nfs4_ff_layout_mirror *m2)
 158 {
 159         int i, j;
 160
 161         if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 162                 return false;
 163         for (i = 0; i < m1->fh_versions_cnt; i++) {
 164                 bool found_fh = false;
 165                 for (j = 0; j < m2->fh_versions_cnt; j++) {
 166                         if (nfs_compare_fh(&m1->fh_versions[i],
 167                                         &m2->fh_versions[j]) == 0) {
 168                                 found_fh = true;
 169                                 break;
 170                         }
 171                 }
 172                 if (!found_fh)
 173                         return false;
 174         }
 175         return true;
 176 }
 177
 178 static struct nfs4_ff_layout_mirror *
 179 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 180                 struct nfs4_ff_layout_mirror *mirror)
 181 {
 182         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 183         struct nfs4_ff_layout_mirror *pos;
 184         struct inode *inode = lo->plh_inode;
 185
 186         spin_lock(&inode->i_lock);
 187         list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 188                 if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
 189                         continue;
 190                 if (!ff_mirror_match_fh(mirror, pos))
 191                         continue;
 192                 if (refcount_inc_not_zero(&pos->ref)) {
 193                         spin_unlock(&inode->i_lock);
 194                         return pos;
 195                 }
 196         }
 197         list_add(&mirror->mirrors, &ff_layout->mirrors);
 198         mirror->layout = lo;
 199         spin_unlock(&inode->i_lock);
 200         return mirror;
 201 }
 202
 203 static void
 204 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 205 {
 206         struct inode *inode;
 207         if (mirror->layout == NULL)
 208                 return;
 209         inode = mirror->layout->plh_inode;
 210         spin_lock(&inode->i_lock);
 211         list_del(&mirror->mirrors);
 212         spin_unlock(&inode->i_lock);
 213         mirror->layout = NULL;
 214 }
 215
 216 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 217 {
 218         struct nfs4_ff_layout_mirror *mirror;
 219
 220         mirror = kzalloc(sizeof(*mirror), gfp_flags);
 221         if (mirror != NULL) {
 222                 spin_lock_init(&mirror->lock);
 223                 refcount_set(&mirror->ref, 1);
 224                 INIT_LIST_HEAD(&mirror->mirrors);
 225         }
 226         return mirror;
 227 }
 228
 229 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 230 {
 231         const struct cred       *cred;
 232
 233         ff_layout_remove_mirror(mirror);
 234         kfree(mirror->fh_versions);
 235         cred = rcu_access_pointer(mirror->ro_cred);
 236         put_cred(cred);
 237         cred = rcu_access_pointer(mirror->rw_cred);
 238         put_cred(cred);
 239         nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 240         kfree(mirror);
 241 }
 242
 243 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 244 {
 245         if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
 246                 ff_layout_free_mirror(mirror);
 247 }
 248
 249 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 250 {
 251         int i;
 252
 253         if (fls->mirror_array) {
 254                 for (i = 0; i < fls->mirror_array_cnt; i++) {
 255                         /* normally mirror_ds is freed in
 256                          * .free_deviceid_node but we still do it here
 257                          * for .alloc_lseg error path */
 258                         ff_layout_put_mirror(fls->mirror_array[i]);
 259                 }
 260                 kfree(fls->mirror_array);
 261                 fls->mirror_array = NULL;
 262         }
 263 }
 264
 265 static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 266 {
 267         int ret = 0;
 268
 269         dprintk("--> %s\n", __func__);
 270
 271         /* FIXME: remove this check when layout segment support is added */
 272         if (lgr->range.offset != 0 ||
 273             lgr->range.length != NFS4_MAX_UINT64) {
 274                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 275                         __func__);
 276                 ret = -EINVAL;
 277         }
 278
 279         dprintk("--> %s returns %d\n", __func__, ret);
 280         return ret;
 281 }
 282
 283 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 284 {
 285         if (fls) {
 286                 ff_layout_free_mirror_array(fls);
 287                 kfree(fls);
 288         }
 289 }
 290
 291 static bool
 292 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 293                 const struct pnfs_layout_range *l2)
 294 {
 295         u64 end1, end2;
 296
 297         if (l1->iomode != l2->iomode)
 298                 return l1->iomode != IOMODE_READ;
 299         end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 300         end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 301         if (end1 < l2->offset)
 302                 return false;
 303         if (end2 < l1->offset)
 304                 return true;
 305         return l2->offset <= l1->offset;
 306 }
 307
 308 static bool
 309 ff_lseg_merge(struct pnfs_layout_segment *new,
 310                 struct pnfs_layout_segment *old)
 311 {
 312         u64 new_end, old_end;
 313
 314         if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 315                 return false;
 316         if (new->pls_range.iomode != old->pls_range.iomode)
 317                 return false;
 318         old_end = pnfs_calc_offset_end(old->pls_range.offset,
 319                         old->pls_range.length);
 320         if (old_end < new->pls_range.offset)
 321                 return false;
 322         new_end = pnfs_calc_offset_end(new->pls_range.offset,
 323                         new->pls_range.length);
 324         if (new_end < old->pls_range.offset)
 325                 return false;
 326
 327         /* Mergeable: copy info from 'old' to 'new' */
 328         if (new_end < old_end)
 329                 new_end = old_end;
 330         if (new->pls_range.offset < old->pls_range.offset)
 331                 new->pls_range.offset = old->pls_range.offset;
 332         new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 333                         new_end);
 334         if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 335                 set_bit(NFS_LSEG_ROC, &new->pls_flags);
 336         return true;
 337 }
 338
 339 static void
 340 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 341                 struct pnfs_layout_segment *lseg,
 342                 struct list_head *free_me)
 343 {
 344         pnfs_generic_layout_insert_lseg(lo, lseg,
 345                         ff_lseg_range_is_after,
 346                         ff_lseg_merge,
 347                         free_me);
 348 }
 349
 350 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 351 {
 352         int i, j;
 353
 354         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 355                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 356                         if (fls->mirror_array[i]->efficiency <
 357                             fls->mirror_array[j]->efficiency)
 358                                 swap(fls->mirror_array[i],
 359                                      fls->mirror_array[j]);
 360         }
 361 }
 362
 363 static struct pnfs_layout_segment *
 364 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 365                      struct nfs4_layoutget_res *lgr,
 366                      gfp_t gfp_flags)
 367 {
 368         struct pnfs_layout_segment *ret;
 369         struct nfs4_ff_layout_segment *fls = NULL;
 370         struct xdr_stream stream;
 371         struct xdr_buf buf;
 372         struct page *scratch;
 373         u64 stripe_unit;
 374         u32 mirror_array_cnt;
 375         __be32 *p;
 376         int i, rc;
 377
 378         dprintk("--> %s\n", __func__);
 379         scratch = alloc_page(gfp_flags);
 380         if (!scratch)
 381                 return ERR_PTR(-ENOMEM);
 382
 383         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 384                               lgr->layoutp->len);
 385         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 386
 387         /* stripe unit and mirror_array_cnt */
 388         rc = -EIO;
 389         p = xdr_inline_decode(&stream, 8 + 4);
 390         if (!p)
 391                 goto out_err_free;
 392
 393         p = xdr_decode_hyper(p, &stripe_unit);
 394         mirror_array_cnt = be32_to_cpup(p++);
 395         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 396                 stripe_unit, mirror_array_cnt);
 397
 398         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 399             mirror_array_cnt == 0)
 400                 goto out_err_free;
 401
 402         rc = -ENOMEM;
 403         fls = kzalloc(sizeof(*fls), gfp_flags);
 404         if (!fls)
 405                 goto out_err_free;
 406
 407         fls->mirror_array_cnt = mirror_array_cnt;
 408         fls->stripe_unit = stripe_unit;
 409         fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 410                                     sizeof(fls->mirror_array[0]), gfp_flags);
 411         if (fls->mirror_array == NULL)
 412                 goto out_err_free;
 413
 414         for (i = 0; i < fls->mirror_array_cnt; i++) {
 415                 struct nfs4_ff_layout_mirror *mirror;
 416                 struct cred *kcred;
 417                 const struct cred __rcu *cred;
 418                 kuid_t uid;
 419                 kgid_t gid;
 420                 u32 ds_count, fh_count, id;
 421                 int j;
 422
 423                 rc = -EIO;
 424                 p = xdr_inline_decode(&stream, 4);
 425                 if (!p)
 426                         goto out_err_free;
 427                 ds_count = be32_to_cpup(p);
 428
 429                 /* FIXME: allow for striping? */
 430                 if (ds_count != 1)
 431                         goto out_err_free;
 432
 433                 fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 434                 if (fls->mirror_array[i] == NULL) {
 435                         rc = -ENOMEM;
 436                         goto out_err_free;
 437                 }
 438
 439                 fls->mirror_array[i]->ds_count = ds_count;
 440
 441                 /* deviceid */
 442                 rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
 443                 if (rc)
 444                         goto out_err_free;
 445
 446                 /* efficiency */
 447                 rc = -EIO;
 448                 p = xdr_inline_decode(&stream, 4);
 449                 if (!p)
 450                         goto out_err_free;
 451                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 452
 453                 /* stateid */
 454                 rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 455                 if (rc)
 456                         goto out_err_free;
 457
 458                 /* fh */
 459                 rc = -EIO;
 460                 p = xdr_inline_decode(&stream, 4);
 461                 if (!p)
 462                         goto out_err_free;
 463                 fh_count = be32_to_cpup(p);
 464
 465                 fls->mirror_array[i]->fh_versions =
 466                         kcalloc(fh_count, sizeof(struct nfs_fh),
 467                                 gfp_flags);
 468                 if (fls->mirror_array[i]->fh_versions == NULL) {
 469                         rc = -ENOMEM;
 470                         goto out_err_free;
 471                 }
 472
 473                 for (j = 0; j < fh_count; j++) {
 474                         rc = decode_nfs_fh(&stream,
 475                                            &fls->mirror_array[i]->fh_versions[j]);
 476                         if (rc)
 477                                 goto out_err_free;
 478                 }
 479
 480                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 481
 482                 /* user */
 483                 rc = decode_name(&stream, &id);
 484                 if (rc)
 485                         goto out_err_free;
 486
 487                 uid = make_kuid(&init_user_ns, id);
 488
 489                 /* group */
 490                 rc = decode_name(&stream, &id);
 491                 if (rc)
 492                         goto out_err_free;
 493
 494                 gid = make_kgid(&init_user_ns, id);
 495
 496                 if (gfp_flags & __GFP_FS)
 497                         kcred = prepare_kernel_cred(NULL);
 498                 else {
 499                         unsigned int nofs_flags = memalloc_nofs_save();
 500                         kcred = prepare_kernel_cred(NULL);
 501                         memalloc_nofs_restore(nofs_flags);
 502                 }
 503                 rc = -ENOMEM;
 504                 if (!kcred)
 505                         goto out_err_free;
 506                 kcred->fsuid = uid;
 507                 kcred->fsgid = gid;
 508                 cred = RCU_INITIALIZER(kcred);
 509
 510                 if (lgr->range.iomode == IOMODE_READ)
 511                         rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 512                 else
 513                         rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 514
 515                 mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 516                 if (mirror != fls->mirror_array[i]) {
 517                         /* swap cred ptrs so free_mirror will clean up old */
 518                         if (lgr->range.iomode == IOMODE_READ) {
 519                                 cred = xchg(&mirror->ro_cred, cred);
 520                                 rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 521                         } else {
 522                                 cred = xchg(&mirror->rw_cred, cred);
 523                                 rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 524                         }
 525                         ff_layout_free_mirror(fls->mirror_array[i]);
 526                         fls->mirror_array[i] = mirror;
 527                 }
 528
 529                 dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 530                         lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 531                         from_kuid(&init_user_ns, uid),
 532                         from_kgid(&init_user_ns, gid));
 533         }
 534
 535         p = xdr_inline_decode(&stream, 4);
 536         if (!p)
 537                 goto out_sort_mirrors;
 538         fls->flags = be32_to_cpup(p);
 539
 540         p = xdr_inline_decode(&stream, 4);
 541         if (!p)
 542                 goto out_sort_mirrors;
 543         for (i=0; i < fls->mirror_array_cnt; i++)
 544                 fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 545
 546 out_sort_mirrors:
 547         ff_layout_sort_mirrors(fls);
 548         rc = ff_layout_check_layout(lgr);
 549         if (rc)
 550                 goto out_err_free;
 551         ret = &fls->generic_hdr;
 552         dprintk("<-- %s (success)\n", __func__);
 553 out_free_page:
 554         __free_page(scratch);
 555         return ret;
 556 out_err_free:
 557         _ff_layout_free_lseg(fls);
 558         ret = ERR_PTR(rc);
 559         dprintk("<-- %s (%d)\n", __func__, rc);
 560         goto out_free_page;
 561 }
 562
 563 static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 564 {
 565         struct pnfs_layout_segment *lseg;
 566
 567         list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 568                 if (lseg->pls_range.iomode == IOMODE_RW)
 569                         return true;
 570
 571         return false;
 572 }
 573
 574 static void
 575 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 576 {
 577         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 578
 579         dprintk("--> %s\n", __func__);
 580
 581         if (lseg->pls_range.iomode == IOMODE_RW) {
 582                 struct nfs4_flexfile_layout *ffl;
 583                 struct inode *inode;
 584
 585                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 586                 inode = ffl->generic_hdr.plh_inode;
 587                 spin_lock(&inode->i_lock);
 588                 if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 589                         ffl->commit_info.nbuckets = 0;
 590                         kfree(ffl->commit_info.buckets);
 591                         ffl->commit_info.buckets = NULL;
 592                 }
 593                 spin_unlock(&inode->i_lock);
 594         }
 595         _ff_layout_free_lseg(fls);
 596 }
 597
 598 /* Return 1 until we have multiple lsegs support */
 599 static int
 600 ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 601 {
 602         return 1;
 603 }
 604
 605 static void
 606 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 607 {
 608         /* first IO request? */
 609         if (atomic_inc_return(&timer->n_ops) == 1) {
 610                 timer->start_time = now;
 611         }
 612 }
 613
 614 static ktime_t
 615 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 616 {
 617         ktime_t start;
 618
 619         if (atomic_dec_return(&timer->n_ops) < 0)
 620                 WARN_ON_ONCE(1);
 621
 622         start = timer->start_time;
 623         timer->start_time = now;
 624         return ktime_sub(now, start);
 625 }
 626
 627 static bool
 628 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 629                             struct nfs4_ff_layoutstat *layoutstat,
 630                             ktime_t now)
 631 {
 632         s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 633         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 634
 635         nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 636         if (!mirror->start_time)
 637                 mirror->start_time = now;
 638         if (mirror->report_interval != 0)
 639                 report_interval = (s64)mirror->report_interval * 1000LL;
 640         else if (layoutstats_timer != 0)
 641                 report_interval = (s64)layoutstats_timer * 1000LL;
 642         if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 643                         report_interval) {
 644                 ffl->last_report_time = now;
 645                 return true;
 646         }
 647
 648         return false;
 649 }
 650
 651 static void
 652 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 653                 __u64 requested)
 654 {
 655         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 656
 657         iostat->ops_requested++;
 658         iostat->bytes_requested += requested;
 659 }
 660
 661 static void
 662 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 663                 __u64 requested,
 664                 __u64 completed,
 665                 ktime_t time_completed,
 666                 ktime_t time_started)
 667 {
 668         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 669         ktime_t completion_time = ktime_sub(time_completed, time_started);
 670         ktime_t timer;
 671
 672         iostat->ops_completed++;
 673         iostat->bytes_completed += completed;
 674         iostat->bytes_not_delivered += requested - completed;
 675
 676         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 677         iostat->total_busy_time =
 678                         ktime_add(iostat->total_busy_time, timer);
 679         iostat->aggregate_completion_time =
 680                         ktime_add(iostat->aggregate_completion_time,
 681                                         completion_time);
 682 }
 683
 684 static void
 685 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 686                 struct nfs4_ff_layout_mirror *mirror,
 687                 __u64 requested, ktime_t now)
 688 {
 689         bool report;
 690
 691         spin_lock(&mirror->lock);
 692         report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 693         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 694         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 695         spin_unlock(&mirror->lock);
 696
 697         if (report)
 698                 pnfs_report_layoutstat(inode, GFP_KERNEL);
 699 }
 700
 701 static void
 702 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 703                 struct nfs4_ff_layout_mirror *mirror,
 704                 __u64 requested,
 705                 __u64 completed)
 706 {
 707         spin_lock(&mirror->lock);
 708         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 709                         requested, completed,
 710                         ktime_get(), task->tk_start);
 711         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 712         spin_unlock(&mirror->lock);
 713 }
 714
 715 static void
 716 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 717                 struct nfs4_ff_layout_mirror *mirror,
 718                 __u64 requested, ktime_t now)
 719 {
 720         bool report;
 721
 722         spin_lock(&mirror->lock);
 723         report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 724         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 725         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 726         spin_unlock(&mirror->lock);
 727
 728         if (report)
 729                 pnfs_report_layoutstat(inode, GFP_NOIO);
 730 }
 731
 732 static void
 733 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 734                 struct nfs4_ff_layout_mirror *mirror,
 735                 __u64 requested,
 736                 __u64 completed,
 737                 enum nfs3_stable_how committed)
 738 {
 739         if (committed == NFS_UNSTABLE)
 740                 requested = completed = 0;
 741
 742         spin_lock(&mirror->lock);
 743         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 744                         requested, completed, ktime_get(), task->tk_start);
 745         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 746         spin_unlock(&mirror->lock);
 747 }
 748
 749 static int
 750 ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 751                             struct nfs_commit_info *cinfo,
 752                             gfp_t gfp_flags)
 753 {
 754         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 755         struct pnfs_commit_bucket *buckets;
 756         int size;
 757
 758         if (cinfo->ds->nbuckets != 0) {
 759                 /* This assumes there is only one RW lseg per file.
 760                  * To support multiple lseg per file, we need to
 761                  * change struct pnfs_commit_bucket to allow dynamic
 762                  * increasing nbuckets.
 763                  */
 764                 return 0;
 765         }
 766
 767         size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 768
 769         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 770                           gfp_flags);
 771         if (!buckets)
 772                 return -ENOMEM;
 773         else {
 774                 int i;
 775
 776                 spin_lock(&cinfo->inode->i_lock);
 777                 if (cinfo->ds->nbuckets != 0)
 778                         kfree(buckets);
 779                 else {
 780                         cinfo->ds->buckets = buckets;
 781                         cinfo->ds->nbuckets = size;
 782                         for (i = 0; i < size; i++) {
 783                                 INIT_LIST_HEAD(&buckets[i].written);
 784                                 INIT_LIST_HEAD(&buckets[i].committing);
 785                                 /* mark direct verifier as unset */
 786                                 buckets[i].direct_verf.committed =
 787                                         NFS_INVALID_STABLE_HOW;
 788                         }
 789                 }
 790                 spin_unlock(&cinfo->inode->i_lock);
 791                 return 0;
 792         }
 793 }
 794
 795 static void
 796 ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, int idx)
 797 {
 798         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 799
 800         if (devid)
 801                 nfs4_mark_deviceid_unavailable(devid);
 802 }
 803
 804 static void
 805 ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, int idx)
 806 {
 807         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 808
 809         if (devid)
 810                 nfs4_mark_deviceid_available(devid);
 811 }
 812
 813 static struct nfs4_pnfs_ds *
 814 ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 815                              int start_idx, int *best_idx,
 816                              bool check_device)
 817 {
 818         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 819         struct nfs4_ff_layout_mirror *mirror;
 820         struct nfs4_pnfs_ds *ds;
 821         bool fail_return = false;
 822         int idx;
 823
 824         /* mirrors are initially sorted by efficiency */
 825         for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 826                 if (idx+1 == fls->mirror_array_cnt)
 827                         fail_return = !check_device;
 828
 829                 mirror = FF_LAYOUT_COMP(lseg, idx);
 830                 ds = nfs4_ff_layout_prepare_ds(lseg, mirror, fail_return);
 831                 if (!ds)
 832                         continue;
 833
 834                 if (check_device &&
 835                     nfs4_test_deviceid_unavailable(&mirror->mirror_ds->id_node))
 836                         continue;
 837
 838                 *best_idx = idx;
 839                 return ds;
 840         }
 841
 842         return NULL;
 843 }
 844
 845 static struct nfs4_pnfs_ds *
 846 ff_layout_choose_any_ds_for_read(struct pnfs_layout_segment *lseg,
 847                                  int start_idx, int *best_idx)
 848 {
 849         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, false);
 850 }
 851
 852 static struct nfs4_pnfs_ds *
 853 ff_layout_choose_valid_ds_for_read(struct pnfs_layout_segment *lseg,
 854                                    int start_idx, int *best_idx)
 855 {
 856         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, true);
 857 }
 858
 859 static struct nfs4_pnfs_ds *
 860 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 861                                   int start_idx, int *best_idx)
 862 {
 863         struct nfs4_pnfs_ds *ds;
 864
 865         ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx);
 866         if (ds)
 867                 return ds;
 868         return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx);
 869 }
 870
 871 static void
 872 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 873                       struct nfs_page *req,
 874                       bool strict_iomode)
 875 {
 876         pnfs_put_lseg(pgio->pg_lseg);
 877         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 878                                            nfs_req_openctx(req),
 879                                            0,
 880                                            NFS4_MAX_UINT64,
 881                                            IOMODE_READ,
 882                                            strict_iomode,
 883                                            GFP_KERNEL);
 884         if (IS_ERR(pgio->pg_lseg)) {
 885                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 886                 pgio->pg_lseg = NULL;
 887         }
 888 }
 889
 890 static void
 891 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 892                         struct nfs_page *req)
 893 {
 894         struct nfs_pgio_mirror *pgm;
 895         struct nfs4_ff_layout_mirror *mirror;
 896         struct nfs4_pnfs_ds *ds;
 897         int ds_idx;
 898
 899 retry:
 900         pnfs_generic_pg_check_layout(pgio);
 901         /* Use full layout for now */
 902         if (!pgio->pg_lseg) {
 903                 ff_layout_pg_get_read(pgio, req, false);
 904                 if (!pgio->pg_lseg)
 905                         goto out_nolseg;
 906         }
 907         if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 908                 ff_layout_pg_get_read(pgio, req, true);
 909                 if (!pgio->pg_lseg)
 910                         goto out_nolseg;
 911         }
 912
 913         ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 914         if (!ds) {
 915                 if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 916                         goto out_mds;
 917                 pnfs_put_lseg(pgio->pg_lseg);
 918                 pgio->pg_lseg = NULL;
 919                 /* Sleep for 1 second before retrying */
 920                 ssleep(1);
 921                 goto retry;
 922         }
 923
 924         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 925
 926         pgio->pg_mirror_idx = ds_idx;
 927
 928         /* read always uses only one mirror - idx 0 for pgio layer */
 929         pgm = &pgio->pg_mirrors[0];
 930         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 931
 932         if (NFS_SERVER(pgio->pg_inode)->flags &
 933                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
 934                 pgio->pg_maxretrans = io_maxretrans;
 935         return;
 936 out_nolseg:
 937         if (pgio->pg_error < 0)
 938                 return;
 939 out_mds:
 940         trace_pnfs_mds_fallback_pg_init_read(pgio->pg_inode,
 941                         0, NFS4_MAX_UINT64, IOMODE_READ,
 942                         NFS_I(pgio->pg_inode)->layout,
 943                         pgio->pg_lseg);
 944         pnfs_put_lseg(pgio->pg_lseg);
 945         pgio->pg_lseg = NULL;
 946         pgio->pg_maxretrans = 0;
 947         nfs_pageio_reset_read_mds(pgio);
 948 }
 949
 950 static void
 951 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 952                         struct nfs_page *req)
 953 {
 954         struct nfs4_ff_layout_mirror *mirror;
 955         struct nfs_pgio_mirror *pgm;
 956         struct nfs_commit_info cinfo;
 957         struct nfs4_pnfs_ds *ds;
 958         int i;
 959         int status;
 960
 961 retry:
 962         pnfs_generic_pg_check_layout(pgio);
 963         if (!pgio->pg_lseg) {
 964                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 965                                                    nfs_req_openctx(req),
 966                                                    0,
 967                                                    NFS4_MAX_UINT64,
 968                                                    IOMODE_RW,
 969                                                    false,
 970                                                    GFP_NOFS);
 971                 if (IS_ERR(pgio->pg_lseg)) {
 972                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 973                         pgio->pg_lseg = NULL;
 974                         return;
 975                 }
 976         }
 977         /* If no lseg, fall back to write through mds */
 978         if (pgio->pg_lseg == NULL)
 979                 goto out_mds;
 980
 981         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 982         status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 983         if (status < 0)
 984                 goto out_mds;
 985
 986         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 987         if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 988             FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 989                 goto out_mds;
 990
 991         for (i = 0; i < pgio->pg_mirror_count; i++) {
 992                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 993                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
 994                 if (!ds) {
 995                         if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 996                                 goto out_mds;
 997                         pnfs_put_lseg(pgio->pg_lseg);
 998                         pgio->pg_lseg = NULL;
 999                         /* Sleep for 1 second before retrying */
1000                         ssleep(1);
1001                         goto retry;
1002                 }
1003                 pgm = &pgio->pg_mirrors[i];
1004                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
1005         }
1006
1007         if (NFS_SERVER(pgio->pg_inode)->flags &
1008                         (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))
1009                 pgio->pg_maxretrans = io_maxretrans;
1010         return;
1011
1012 out_mds:
1013         trace_pnfs_mds_fallback_pg_init_write(pgio->pg_inode,
1014                         0, NFS4_MAX_UINT64, IOMODE_RW,
1015                         NFS_I(pgio->pg_inode)->layout,
1016                         pgio->pg_lseg);
1017         pnfs_put_lseg(pgio->pg_lseg);
1018         pgio->pg_lseg = NULL;
1019         pgio->pg_maxretrans = 0;
1020         nfs_pageio_reset_write_mds(pgio);
1021 }
1022
1023 static unsigned int
1024 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
1025                                     struct nfs_page *req)
1026 {
1027         if (!pgio->pg_lseg) {
1028                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1029                                                    nfs_req_openctx(req),
1030                                                    0,
1031                                                    NFS4_MAX_UINT64,
1032                                                    IOMODE_RW,
1033                                                    false,
1034                                                    GFP_NOFS);
1035                 if (IS_ERR(pgio->pg_lseg)) {
1036                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
1037                         pgio->pg_lseg = NULL;
1038                         goto out;
1039                 }
1040         }
1041         if (pgio->pg_lseg)
1042                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
1043
1044         trace_pnfs_mds_fallback_pg_get_mirror_count(pgio->pg_inode,
1045                         0, NFS4_MAX_UINT64, IOMODE_RW,
1046                         NFS_I(pgio->pg_inode)->layout,
1047                         pgio->pg_lseg);
1048         /* no lseg means that pnfs is not in use, so no mirroring here */
1049         nfs_pageio_reset_write_mds(pgio);
1050 out:
1051         return 1;
1052 }
1053
1054 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
1055         .pg_init = ff_layout_pg_init_read,
1056         .pg_test = pnfs_generic_pg_test,
1057         .pg_doio = pnfs_generic_pg_readpages,
1058         .pg_cleanup = pnfs_generic_pg_cleanup,
1059 };
1060
1061 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
1062         .pg_init = ff_layout_pg_init_write,
1063         .pg_test = pnfs_generic_pg_test,
1064         .pg_doio = pnfs_generic_pg_writepages,
1065         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1066         .pg_cleanup = pnfs_generic_pg_cleanup,
1067 };
1068
1069 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1070 {
1071         struct rpc_task *task = &hdr->task;
1072
1073         pnfs_layoutcommit_inode(hdr->inode, false);
1074
1075         if (retry_pnfs) {
1076                 dprintk("%s Reset task %5u for i/o through pNFS "
1077                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1078                         hdr->task.tk_pid,
1079                         hdr->inode->i_sb->s_id,
1080                         (unsigned long long)NFS_FILEID(hdr->inode),
1081                         hdr->args.count,
1082                         (unsigned long long)hdr->args.offset);
1083
1084                 hdr->completion_ops->reschedule_io(hdr);
1085                 return;
1086         }
1087
1088         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1089                 dprintk("%s Reset task %5u for i/o through MDS "
1090                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1091                         hdr->task.tk_pid,
1092                         hdr->inode->i_sb->s_id,
1093                         (unsigned long long)NFS_FILEID(hdr->inode),
1094                         hdr->args.count,
1095                         (unsigned long long)hdr->args.offset);
1096
1097                 trace_pnfs_mds_fallback_write_done(hdr->inode,
1098                                 hdr->args.offset, hdr->args.count,
1099                                 IOMODE_RW, NFS_I(hdr->inode)->layout,
1100                                 hdr->lseg);
1101                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1102         }
1103 }
1104
1105 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1106 {
1107         struct rpc_task *task = &hdr->task;
1108
1109         pnfs_layoutcommit_inode(hdr->inode, false);
1110
1111         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1112                 dprintk("%s Reset task %5u for i/o through MDS "
1113                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1114                         hdr->task.tk_pid,
1115                         hdr->inode->i_sb->s_id,
1116                         (unsigned long long)NFS_FILEID(hdr->inode),
1117                         hdr->args.count,
1118                         (unsigned long long)hdr->args.offset);
1119
1120                 trace_pnfs_mds_fallback_read_done(hdr->inode,
1121                                 hdr->args.offset, hdr->args.count,
1122                                 IOMODE_READ, NFS_I(hdr->inode)->layout,
1123                                 hdr->lseg);
1124                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1125         }
1126 }
1127
1128 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1129                                            struct nfs4_state *state,
1130                                            struct nfs_client *clp,
1131                                            struct pnfs_layout_segment *lseg,
1132                                            int idx)
1133 {
1134         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1135         struct inode *inode = lo->plh_inode;
1136         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1137         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1138
1139         switch (task->tk_status) {
1140         case -NFS4ERR_BADSESSION:
1141         case -NFS4ERR_BADSLOT:
1142         case -NFS4ERR_BAD_HIGH_SLOT:
1143         case -NFS4ERR_DEADSESSION:
1144         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1145         case -NFS4ERR_SEQ_FALSE_RETRY:
1146         case -NFS4ERR_SEQ_MISORDERED:
1147                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1148                         "flags 0x%x\n", __func__, task->tk_status,
1149                         clp->cl_exchange_flags);
1150                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1151                 break;
1152         case -NFS4ERR_DELAY:
1153         case -NFS4ERR_GRACE:
1154                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1155                 break;
1156         case -NFS4ERR_RETRY_UNCACHED_REP:
1157                 break;
1158         /* Invalidate Layout errors */
1159         case -NFS4ERR_PNFS_NO_LAYOUT:
1160         case -ESTALE:           /* mapped NFS4ERR_STALE */
1161         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1162         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1163         case -NFS4ERR_FHEXPIRED:
1164         case -NFS4ERR_WRONG_TYPE:
1165                 dprintk("%s Invalid layout error %d\n", __func__,
1166                         task->tk_status);
1167                 /*
1168                  * Destroy layout so new i/o will get a new layout.
1169                  * Layout will not be destroyed until all current lseg
1170                  * references are put. Mark layout as invalid to resend failed
1171                  * i/o and all i/o waiting on the slot table to the MDS until
1172                  * layout is destroyed and a new valid layout is obtained.
1173                  */
1174                 pnfs_destroy_layout(NFS_I(inode));
1175                 rpc_wake_up(&tbl->slot_tbl_waitq);
1176                 goto reset;
1177         /* RPC connection errors */
1178         case -ECONNREFUSED:
1179         case -EHOSTDOWN:
1180         case -EHOSTUNREACH:
1181         case -ENETUNREACH:
1182         case -EIO:
1183         case -ETIMEDOUT:
1184         case -EPIPE:
1185                 dprintk("%s DS connection error %d\n", __func__,
1186                         task->tk_status);
1187                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1188                                 &devid->deviceid);
1189                 rpc_wake_up(&tbl->slot_tbl_waitq);
1190                 /* fall through */
1191         default:
1192                 if (ff_layout_avoid_mds_available_ds(lseg))
1193                         return -NFS4ERR_RESET_TO_PNFS;
1194 reset:
1195                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1196                         task->tk_status);
1197                 return -NFS4ERR_RESET_TO_MDS;
1198         }
1199         task->tk_status = 0;
1200         return -EAGAIN;
1201 }
1202
1203 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1204 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1205                                            struct pnfs_layout_segment *lseg,
1206                                            int idx)
1207 {
1208         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1209
1210         switch (task->tk_status) {
1211         /* File access problems. Don't mark the device as unavailable */
1212         case -EACCES:
1213         case -ESTALE:
1214         case -EISDIR:
1215         case -EBADHANDLE:
1216         case -ELOOP:
1217         case -ENOSPC:
1218                 break;
1219         case -EJUKEBOX:
1220                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1221                 goto out_retry;
1222         default:
1223                 dprintk("%s DS connection error %d\n", __func__,
1224                         task->tk_status);
1225                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1226                                 &devid->deviceid);
1227         }
1228         /* FIXME: Need to prevent infinite looping here. */
1229         return -NFS4ERR_RESET_TO_PNFS;
1230 out_retry:
1231         task->tk_status = 0;
1232         rpc_restart_call_prepare(task);
1233         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1234         return -EAGAIN;
1235 }
1236
1237 static int ff_layout_async_handle_error(struct rpc_task *task,
1238                                         struct nfs4_state *state,
1239                                         struct nfs_client *clp,
1240                                         struct pnfs_layout_segment *lseg,
1241                                         int idx)
1242 {
1243         int vers = clp->cl_nfs_mod->rpc_vers->number;
1244
1245         if (task->tk_status >= 0) {
1246                 ff_layout_mark_ds_reachable(lseg, idx);
1247                 return 0;
1248         }
1249
1250         /* Handle the case of an invalid layout segment */
1251         if (!pnfs_is_valid_lseg(lseg))
1252                 return -NFS4ERR_RESET_TO_PNFS;
1253
1254         switch (vers) {
1255         case 3:
1256                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1257         case 4:
1258                 return ff_layout_async_handle_error_v4(task, state, clp,
1259                                                        lseg, idx);
1260         default:
1261                 /* should never happen */
1262                 WARN_ON_ONCE(1);
1263                 return 0;
1264         }
1265 }
1266
1267 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1268                                         int idx, u64 offset, u64 length,
1269                                         u32 status, int opnum, int error)
1270 {
1271         struct nfs4_ff_layout_mirror *mirror;
1272         int err;
1273
1274         if (status == 0) {
1275                 switch (error) {
1276                 case -ETIMEDOUT:
1277                 case -EPFNOSUPPORT:
1278                 case -EPROTONOSUPPORT:
1279                 case -EOPNOTSUPP:
1280                 case -ECONNREFUSED:
1281                 case -ECONNRESET:
1282                 case -EHOSTDOWN:
1283                 case -EHOSTUNREACH:
1284                 case -ENETUNREACH:
1285                 case -EADDRINUSE:
1286                 case -ENOBUFS:
1287                 case -EPIPE:
1288                 case -EPERM:
1289                         status = NFS4ERR_NXIO;
1290                         break;
1291                 case -EACCES:
1292                         status = NFS4ERR_ACCESS;
1293                         break;
1294                 default:
1295                         return;
1296                 }
1297         }
1298
1299         switch (status) {
1300         case NFS4ERR_DELAY:
1301         case NFS4ERR_GRACE:
1302                 return;
1303         default:
1304                 break;
1305         }
1306
1307         mirror = FF_LAYOUT_COMP(lseg, idx);
1308         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1309                                        mirror, offset, length, status, opnum,
1310                                        GFP_NOIO);
1311         if (status == NFS4ERR_NXIO)
1312                 ff_layout_mark_ds_unreachable(lseg, idx);
1313         pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
1314         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1315 }
1316
1317 /* NFS_PROTO call done callback routines */
1318 static int ff_layout_read_done_cb(struct rpc_task *task,
1319                                 struct nfs_pgio_header *hdr)
1320 {
1321         int new_idx = hdr->pgio_mirror_idx;
1322         int err;
1323
1324         trace_nfs4_pnfs_read(hdr, task->tk_status);
1325         if (task->tk_status < 0)
1326                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1327                                             hdr->args.offset, hdr->args.count,
1328                                             hdr->res.op_status, OP_READ,
1329                                             task->tk_status);
1330         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1331                                            hdr->ds_clp, hdr->lseg,
1332                                            hdr->pgio_mirror_idx);
1333
1334         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1335         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1336         switch (err) {
1337         case -NFS4ERR_RESET_TO_PNFS:
1338                 if (ff_layout_choose_best_ds_for_read(hdr->lseg,
1339                                         hdr->pgio_mirror_idx + 1,
1340                                         &new_idx))
1341                         goto out_layouterror;
1342                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1343                 return task->tk_status;
1344         case -NFS4ERR_RESET_TO_MDS:
1345                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1346                 return task->tk_status;
1347         case -EAGAIN:
1348                 goto out_eagain;
1349         }
1350
1351         return 0;
1352 out_layouterror:
1353         ff_layout_read_record_layoutstats_done(task, hdr);
1354         ff_layout_send_layouterror(hdr->lseg);
1355         hdr->pgio_mirror_idx = new_idx;
1356 out_eagain:
1357         rpc_restart_call_prepare(task);
1358         return -EAGAIN;
1359 }
1360
1361 static bool
1362 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1363 {
1364         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1365 }
1366
1367 /*
1368  * We reference the rpc_cred of the first WRITE that triggers the need for
1369  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1370  * rfc5661 is not clear about which credential should be used.
1371  *
1372  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1373  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1374  * we always send layoutcommit after DS writes.
1375  */
1376 static void
1377 ff_layout_set_layoutcommit(struct inode *inode,
1378                 struct pnfs_layout_segment *lseg,
1379                 loff_t end_offset)
1380 {
1381         if (!ff_layout_need_layoutcommit(lseg))
1382                 return;
1383
1384         pnfs_set_layoutcommit(inode, lseg, end_offset);
1385         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1386                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1387 }
1388
1389 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1390                 struct nfs_pgio_header *hdr)
1391 {
1392         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1393                 return;
1394         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1395                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1396                         hdr->args.count,
1397                         task->tk_start);
1398 }
1399
1400 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1401                 struct nfs_pgio_header *hdr)
1402 {
1403         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1404                 return;
1405         nfs4_ff_layout_stat_io_end_read(task,
1406                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1407                         hdr->args.count,
1408                         hdr->res.count);
1409         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1410 }
1411
1412 static int ff_layout_read_prepare_common(struct rpc_task *task,
1413                                          struct nfs_pgio_header *hdr)
1414 {
1415         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1416                 rpc_exit(task, -EIO);
1417                 return -EIO;
1418         }
1419
1420         ff_layout_read_record_layoutstats_start(task, hdr);
1421         return 0;
1422 }
1423
1424 /*
1425  * Call ops for the async read/write cases
1426  * In the case of dense layouts, the offset needs to be reset to its
1427  * original value.
1428  */
1429 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1430 {
1431         struct nfs_pgio_header *hdr = data;
1432
1433         if (ff_layout_read_prepare_common(task, hdr))
1434                 return;
1435
1436         rpc_call_start(task);
1437 }
1438
1439 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1440 {
1441         struct nfs_pgio_header *hdr = data;
1442
1443         if (nfs4_setup_sequence(hdr->ds_clp,
1444                                 &hdr->args.seq_args,
1445                                 &hdr->res.seq_res,
1446                                 task))
1447                 return;
1448
1449         ff_layout_read_prepare_common(task, hdr);
1450 }
1451
1452 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1453 {
1454         struct nfs_pgio_header *hdr = data;
1455
1456         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1457
1458         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1459             task->tk_status == 0) {
1460                 nfs4_sequence_done(task, &hdr->res.seq_res);
1461                 return;
1462         }
1463
1464         /* Note this may cause RPC to be resent */
1465         hdr->mds_ops->rpc_call_done(task, hdr);
1466 }
1467
1468 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1469 {
1470         struct nfs_pgio_header *hdr = data;
1471
1472         ff_layout_read_record_layoutstats_done(task, hdr);
1473         rpc_count_iostats_metrics(task,
1474             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1475 }
1476
1477 static void ff_layout_read_release(void *data)
1478 {
1479         struct nfs_pgio_header *hdr = data;
1480
1481         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1482         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1483                 ff_layout_send_layouterror(hdr->lseg);
1484                 pnfs_read_resend_pnfs(hdr);
1485         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1486                 ff_layout_reset_read(hdr);
1487         pnfs_generic_rw_release(data);
1488 }
1489
1490
1491 static int ff_layout_write_done_cb(struct rpc_task *task,
1492                                 struct nfs_pgio_header *hdr)
1493 {
1494         loff_t end_offs = 0;
1495         int err;
1496
1497         trace_nfs4_pnfs_write(hdr, task->tk_status);
1498         if (task->tk_status < 0)
1499                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1500                                             hdr->args.offset, hdr->args.count,
1501                                             hdr->res.op_status, OP_WRITE,
1502                                             task->tk_status);
1503         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1504                                            hdr->ds_clp, hdr->lseg,
1505                                            hdr->pgio_mirror_idx);
1506
1507         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1508         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1509         switch (err) {
1510         case -NFS4ERR_RESET_TO_PNFS:
1511                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1512                 return task->tk_status;
1513         case -NFS4ERR_RESET_TO_MDS:
1514                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1515                 return task->tk_status;
1516         case -EAGAIN:
1517                 return -EAGAIN;
1518         }
1519
1520         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1521             hdr->res.verf->committed == NFS_DATA_SYNC)
1522                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1523
1524         /* Note: if the write is unstable, don't set end_offs until commit */
1525         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1526
1527         /* zero out fattr since we don't care DS attr at all */
1528         hdr->fattr.valid = 0;
1529         if (task->tk_status >= 0)
1530                 nfs_writeback_update_inode(hdr);
1531
1532         return 0;
1533 }
1534
1535 static int ff_layout_commit_done_cb(struct rpc_task *task,
1536                                      struct nfs_commit_data *data)
1537 {
1538         int err;
1539
1540         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1541         if (task->tk_status < 0)
1542                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1543                                             data->args.offset, data->args.count,
1544                                             data->res.op_status, OP_COMMIT,
1545                                             task->tk_status);
1546         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1547                                            data->lseg, data->ds_commit_index);
1548
1549         switch (err) {
1550         case -NFS4ERR_RESET_TO_PNFS:
1551                 pnfs_generic_prepare_to_resend_writes(data);
1552                 return -EAGAIN;
1553         case -NFS4ERR_RESET_TO_MDS:
1554                 pnfs_generic_prepare_to_resend_writes(data);
1555                 return -EAGAIN;
1556         case -EAGAIN:
1557                 rpc_restart_call_prepare(task);
1558                 return -EAGAIN;
1559         }
1560
1561         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1562
1563         return 0;
1564 }
1565
1566 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1567                 struct nfs_pgio_header *hdr)
1568 {
1569         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1570                 return;
1571         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1572                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1573                         hdr->args.count,
1574                         task->tk_start);
1575 }
1576
1577 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1578                 struct nfs_pgio_header *hdr)
1579 {
1580         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1581                 return;
1582         nfs4_ff_layout_stat_io_end_write(task,
1583                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1584                         hdr->args.count, hdr->res.count,
1585                         hdr->res.verf->committed);
1586         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1587 }
1588
1589 static int ff_layout_write_prepare_common(struct rpc_task *task,
1590                                           struct nfs_pgio_header *hdr)
1591 {
1592         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1593                 rpc_exit(task, -EIO);
1594                 return -EIO;
1595         }
1596
1597         ff_layout_write_record_layoutstats_start(task, hdr);
1598         return 0;
1599 }
1600
1601 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1602 {
1603         struct nfs_pgio_header *hdr = data;
1604
1605         if (ff_layout_write_prepare_common(task, hdr))
1606                 return;
1607
1608         rpc_call_start(task);
1609 }
1610
1611 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1612 {
1613         struct nfs_pgio_header *hdr = data;
1614
1615         if (nfs4_setup_sequence(hdr->ds_clp,
1616                                 &hdr->args.seq_args,
1617                                 &hdr->res.seq_res,
1618                                 task))
1619                 return;
1620
1621         ff_layout_write_prepare_common(task, hdr);
1622 }
1623
1624 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1625 {
1626         struct nfs_pgio_header *hdr = data;
1627
1628         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1629             task->tk_status == 0) {
1630                 nfs4_sequence_done(task, &hdr->res.seq_res);
1631                 return;
1632         }
1633
1634         /* Note this may cause RPC to be resent */
1635         hdr->mds_ops->rpc_call_done(task, hdr);
1636 }
1637
1638 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1639 {
1640         struct nfs_pgio_header *hdr = data;
1641
1642         ff_layout_write_record_layoutstats_done(task, hdr);
1643         rpc_count_iostats_metrics(task,
1644             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1645 }
1646
1647 static void ff_layout_write_release(void *data)
1648 {
1649         struct nfs_pgio_header *hdr = data;
1650
1651         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1652         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1653                 ff_layout_send_layouterror(hdr->lseg);
1654                 ff_layout_reset_write(hdr, true);
1655         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1656                 ff_layout_reset_write(hdr, false);
1657         pnfs_generic_rw_release(data);
1658 }
1659
1660 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1661                 struct nfs_commit_data *cdata)
1662 {
1663         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1664                 return;
1665         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1666                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1667                         0, task->tk_start);
1668 }
1669
1670 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1671                 struct nfs_commit_data *cdata)
1672 {
1673         struct nfs_page *req;
1674         __u64 count = 0;
1675
1676         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1677                 return;
1678
1679         if (task->tk_status == 0) {
1680                 list_for_each_entry(req, &cdata->pages, wb_list)
1681                         count += req->wb_bytes;
1682         }
1683         nfs4_ff_layout_stat_io_end_write(task,
1684                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1685                         count, count, NFS_FILE_SYNC);
1686         set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1687 }
1688
1689 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1690                 struct nfs_commit_data *cdata)
1691 {
1692         ff_layout_commit_record_layoutstats_start(task, cdata);
1693 }
1694
1695 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1696 {
1697         ff_layout_commit_prepare_common(task, data);
1698         rpc_call_start(task);
1699 }
1700
1701 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1702 {
1703         struct nfs_commit_data *wdata = data;
1704
1705         if (nfs4_setup_sequence(wdata->ds_clp,
1706                                 &wdata->args.seq_args,
1707                                 &wdata->res.seq_res,
1708                                 task))
1709                 return;
1710         ff_layout_commit_prepare_common(task, data);
1711 }
1712
1713 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1714 {
1715         pnfs_generic_write_commit_done(task, data);
1716 }
1717
1718 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1719 {
1720         struct nfs_commit_data *cdata = data;
1721
1722         ff_layout_commit_record_layoutstats_done(task, cdata);
1723         rpc_count_iostats_metrics(task,
1724             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1725 }
1726
1727 static void ff_layout_commit_release(void *data)
1728 {
1729         struct nfs_commit_data *cdata = data;
1730
1731         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1732         pnfs_generic_commit_release(data);
1733 }
1734
1735 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1736         .rpc_call_prepare = ff_layout_read_prepare_v3,
1737         .rpc_call_done = ff_layout_read_call_done,
1738         .rpc_count_stats = ff_layout_read_count_stats,
1739         .rpc_release = ff_layout_read_release,
1740 };
1741
1742 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1743         .rpc_call_prepare = ff_layout_read_prepare_v4,
1744         .rpc_call_done = ff_layout_read_call_done,
1745         .rpc_count_stats = ff_layout_read_count_stats,
1746         .rpc_release = ff_layout_read_release,
1747 };
1748
1749 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1750         .rpc_call_prepare = ff_layout_write_prepare_v3,
1751         .rpc_call_done = ff_layout_write_call_done,
1752         .rpc_count_stats = ff_layout_write_count_stats,
1753         .rpc_release = ff_layout_write_release,
1754 };
1755
1756 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1757         .rpc_call_prepare = ff_layout_write_prepare_v4,
1758         .rpc_call_done = ff_layout_write_call_done,
1759         .rpc_count_stats = ff_layout_write_count_stats,
1760         .rpc_release = ff_layout_write_release,
1761 };
1762
1763 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1764         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1765         .rpc_call_done = ff_layout_commit_done,
1766         .rpc_count_stats = ff_layout_commit_count_stats,
1767         .rpc_release = ff_layout_commit_release,
1768 };
1769
1770 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1771         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1772         .rpc_call_done = ff_layout_commit_done,
1773         .rpc_count_stats = ff_layout_commit_count_stats,
1774         .rpc_release = ff_layout_commit_release,
1775 };
1776
1777 static enum pnfs_try_status
1778 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1779 {
1780         struct pnfs_layout_segment *lseg = hdr->lseg;
1781         struct nfs4_pnfs_ds *ds;
1782         struct rpc_clnt *ds_clnt;
1783         struct nfs4_ff_layout_mirror *mirror;
1784         const struct cred *ds_cred;
1785         loff_t offset = hdr->args.offset;
1786         u32 idx = hdr->pgio_mirror_idx;
1787         int vers;
1788         struct nfs_fh *fh;
1789
1790         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1791                 __func__, hdr->inode->i_ino,
1792                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1793
1794         mirror = FF_LAYOUT_COMP(lseg, idx);
1795         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
1796         if (!ds)
1797                 goto out_failed;
1798
1799         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1800                                                    hdr->inode);
1801         if (IS_ERR(ds_clnt))
1802                 goto out_failed;
1803
1804         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1805         if (!ds_cred)
1806                 goto out_failed;
1807
1808         vers = nfs4_ff_layout_ds_version(mirror);
1809
1810         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1811                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1812
1813         hdr->pgio_done_cb = ff_layout_read_done_cb;
1814         refcount_inc(&ds->ds_clp->cl_count);
1815         hdr->ds_clp = ds->ds_clp;
1816         fh = nfs4_ff_layout_select_ds_fh(mirror);
1817         if (fh)
1818                 hdr->args.fh = fh;
1819
1820         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1821
1822         /*
1823          * Note that if we ever decide to split across DSes,
1824          * then we may need to handle dense-like offsets.
1825          */
1826         hdr->args.offset = offset;
1827         hdr->mds_offset = offset;
1828
1829         /* Perform an asynchronous read to ds */
1830         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1831                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1832                                       &ff_layout_read_call_ops_v4,
1833                           0, RPC_TASK_SOFTCONN);
1834         put_cred(ds_cred);
1835         return PNFS_ATTEMPTED;
1836
1837 out_failed:
1838         if (ff_layout_avoid_mds_available_ds(lseg))
1839                 return PNFS_TRY_AGAIN;
1840         trace_pnfs_mds_fallback_read_pagelist(hdr->inode,
1841                         hdr->args.offset, hdr->args.count,
1842                         IOMODE_READ, NFS_I(hdr->inode)->layout, lseg);
1843         return PNFS_NOT_ATTEMPTED;
1844 }
1845
1846 /* Perform async writes. */
1847 static enum pnfs_try_status
1848 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1849 {
1850         struct pnfs_layout_segment *lseg = hdr->lseg;
1851         struct nfs4_pnfs_ds *ds;
1852         struct rpc_clnt *ds_clnt;
1853         struct nfs4_ff_layout_mirror *mirror;
1854         const struct cred *ds_cred;
1855         loff_t offset = hdr->args.offset;
1856         int vers;
1857         struct nfs_fh *fh;
1858         int idx = hdr->pgio_mirror_idx;
1859
1860         mirror = FF_LAYOUT_COMP(lseg, idx);
1861         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1862         if (!ds)
1863                 goto out_failed;
1864
1865         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1866                                                    hdr->inode);
1867         if (IS_ERR(ds_clnt))
1868                 goto out_failed;
1869
1870         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1871         if (!ds_cred)
1872                 goto out_failed;
1873
1874         vers = nfs4_ff_layout_ds_version(mirror);
1875
1876         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1877                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1878                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1879                 vers);
1880
1881         hdr->pgio_done_cb = ff_layout_write_done_cb;
1882         refcount_inc(&ds->ds_clp->cl_count);
1883         hdr->ds_clp = ds->ds_clp;
1884         hdr->ds_commit_idx = idx;
1885         fh = nfs4_ff_layout_select_ds_fh(mirror);
1886         if (fh)
1887                 hdr->args.fh = fh;
1888
1889         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1890
1891         /*
1892          * Note that if we ever decide to split across DSes,
1893          * then we may need to handle dense-like offsets.
1894          */
1895         hdr->args.offset = offset;
1896
1897         /* Perform an asynchronous write */
1898         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1899                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1900                                       &ff_layout_write_call_ops_v4,
1901                           sync, RPC_TASK_SOFTCONN);
1902         put_cred(ds_cred);
1903         return PNFS_ATTEMPTED;
1904
1905 out_failed:
1906         if (ff_layout_avoid_mds_available_ds(lseg))
1907                 return PNFS_TRY_AGAIN;
1908         trace_pnfs_mds_fallback_write_pagelist(hdr->inode,
1909                         hdr->args.offset, hdr->args.count,
1910                         IOMODE_RW, NFS_I(hdr->inode)->layout, lseg);
1911         return PNFS_NOT_ATTEMPTED;
1912 }
1913
1914 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1915 {
1916         return i;
1917 }
1918
1919 static struct nfs_fh *
1920 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1921 {
1922         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1923
1924         /* FIXME: Assume that there is only one NFS version available
1925          * for the DS.
1926          */
1927         return &flseg->mirror_array[i]->fh_versions[0];
1928 }
1929
1930 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1931 {
1932         struct pnfs_layout_segment *lseg = data->lseg;
1933         struct nfs4_pnfs_ds *ds;
1934         struct rpc_clnt *ds_clnt;
1935         struct nfs4_ff_layout_mirror *mirror;
1936         const struct cred *ds_cred;
1937         u32 idx;
1938         int vers, ret;
1939         struct nfs_fh *fh;
1940
1941         if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1942             test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1943                 goto out_err;
1944
1945         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1946         mirror = FF_LAYOUT_COMP(lseg, idx);
1947         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1948         if (!ds)
1949                 goto out_err;
1950
1951         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1952                                                    data->inode);
1953         if (IS_ERR(ds_clnt))
1954                 goto out_err;
1955
1956         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
1957         if (!ds_cred)
1958                 goto out_err;
1959
1960         vers = nfs4_ff_layout_ds_version(mirror);
1961
1962         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1963                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1964                 vers);
1965         data->commit_done_cb = ff_layout_commit_done_cb;
1966         data->cred = ds_cred;
1967         refcount_inc(&ds->ds_clp->cl_count);
1968         data->ds_clp = ds->ds_clp;
1969         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1970         if (fh)
1971                 data->args.fh = fh;
1972
1973         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1974                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1975                                                &ff_layout_commit_call_ops_v4,
1976                                    how, RPC_TASK_SOFTCONN);
1977         put_cred(ds_cred);
1978         return ret;
1979 out_err:
1980         pnfs_generic_prepare_to_resend_writes(data);
1981         pnfs_generic_commit_release(data);
1982         return -EAGAIN;
1983 }
1984
1985 static int
1986 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1987                            int how, struct nfs_commit_info *cinfo)
1988 {
1989         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1990                                             ff_layout_initiate_commit);
1991 }
1992
1993 static struct pnfs_ds_commit_info *
1994 ff_layout_get_ds_info(struct inode *inode)
1995 {
1996         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1997
1998         if (layout == NULL)
1999                 return NULL;
2000
2001         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
2002 }
2003
2004 static void
2005 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
2006 {
2007         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
2008                                                   id_node));
2009 }
2010
2011 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
2012                                   const struct nfs4_layoutreturn_args *args,
2013                                   const struct nfs4_flexfile_layoutreturn_args *ff_args)
2014 {
2015         __be32 *start;
2016
2017         start = xdr_reserve_space(xdr, 4);
2018         if (unlikely(!start))
2019                 return -E2BIG;
2020
2021         *start = cpu_to_be32(ff_args->num_errors);
2022         /* This assume we always return _ALL_ layouts */
2023         return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
2024 }
2025
2026 static void
2027 encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
2028 {
2029         WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
2030 }
2031
2032 static void
2033 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
2034                             const nfs4_stateid *stateid,
2035                             const struct nfs42_layoutstat_devinfo *devinfo)
2036 {
2037         __be32 *p;
2038
2039         p = xdr_reserve_space(xdr, 8 + 8);
2040         p = xdr_encode_hyper(p, devinfo->offset);
2041         p = xdr_encode_hyper(p, devinfo->length);
2042         encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
2043         p = xdr_reserve_space(xdr, 4*8);
2044         p = xdr_encode_hyper(p, devinfo->read_count);
2045         p = xdr_encode_hyper(p, devinfo->read_bytes);
2046         p = xdr_encode_hyper(p, devinfo->write_count);
2047         p = xdr_encode_hyper(p, devinfo->write_bytes);
2048         encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
2049 }
2050
2051 static void
2052 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
2053                             const nfs4_stateid *stateid,
2054                             const struct nfs42_layoutstat_devinfo *devinfo)
2055 {
2056         ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
2057         ff_layout_encode_ff_layoutupdate(xdr, devinfo,
2058                         devinfo->ld_private.data);
2059 }
2060
2061 /* report nothing for now */
2062 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
2063                 const struct nfs4_layoutreturn_args *args,
2064                 struct nfs4_flexfile_layoutreturn_args *ff_args)
2065 {
2066         __be32 *p;
2067         int i;
2068
2069         p = xdr_reserve_space(xdr, 4);
2070         *p = cpu_to_be32(ff_args->num_dev);
2071         for (i = 0; i < ff_args->num_dev; i++)
2072                 ff_layout_encode_ff_iostat(xdr,
2073                                 &args->layout->plh_stateid,
2074                                 &ff_args->devinfo[i]);
2075 }
2076
2077 static void
2078 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
2079                 unsigned int num_entries)
2080 {
2081         unsigned int i;
2082
2083         for (i = 0; i < num_entries; i++) {
2084                 if (!devinfo[i].ld_private.ops)
2085                         continue;
2086                 if (!devinfo[i].ld_private.ops->free)
2087                         continue;
2088                 devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2089         }
2090 }
2091
2092 static struct nfs4_deviceid_node *
2093 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2094                               struct pnfs_device *pdev, gfp_t gfp_flags)
2095 {
2096         struct nfs4_ff_layout_ds *dsaddr;
2097
2098         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2099         if (!dsaddr)
2100                 return NULL;
2101         return &dsaddr->id_node;
2102 }
2103
2104 static void
2105 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2106                 const void *voidargs,
2107                 const struct nfs4_xdr_opaque_data *ff_opaque)
2108 {
2109         const struct nfs4_layoutreturn_args *args = voidargs;
2110         struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2111         struct xdr_buf tmp_buf = {
2112                 .head = {
2113                         [0] = {
2114                                 .iov_base = page_address(ff_args->pages[0]),
2115                         },
2116                 },
2117                 .buflen = PAGE_SIZE,
2118         };
2119         struct xdr_stream tmp_xdr;
2120         __be32 *start;
2121
2122         dprintk("%s: Begin\n", __func__);
2123
2124         xdr_init_encode(&tmp_xdr, &tmp_buf, NULL, NULL);
2125
2126         ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2127         ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2128
2129         start = xdr_reserve_space(xdr, 4);
2130         *start = cpu_to_be32(tmp_buf.len);
2131         xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2132
2133         dprintk("%s: Return\n", __func__);
2134 }
2135
2136 static void
2137 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2138 {
2139         struct nfs4_flexfile_layoutreturn_args *ff_args;
2140
2141         if (!args->data)
2142                 return;
2143         ff_args = args->data;
2144         args->data = NULL;
2145
2146         ff_layout_free_ds_ioerr(&ff_args->errors);
2147         ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2148
2149         put_page(ff_args->pages[0]);
2150         kfree(ff_args);
2151 }
2152
2153 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2154         .encode = ff_layout_encode_layoutreturn,
2155         .free = ff_layout_free_layoutreturn,
2156 };
2157
2158 static int
2159 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2160 {
2161         struct nfs4_flexfile_layoutreturn_args *ff_args;
2162         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2163
2164         ff_args = kmalloc(sizeof(*ff_args), GFP_KERNEL);
2165         if (!ff_args)
2166                 goto out_nomem;
2167         ff_args->pages[0] = alloc_page(GFP_KERNEL);
2168         if (!ff_args->pages[0])
2169                 goto out_nomem_free;
2170
2171         INIT_LIST_HEAD(&ff_args->errors);
2172         ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2173                         &args->range, &ff_args->errors,
2174                         FF_LAYOUTRETURN_MAXERR);
2175
2176         spin_lock(&args->inode->i_lock);
2177         ff_args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2178                         &ff_args->devinfo[0], ARRAY_SIZE(ff_args->devinfo));
2179         spin_unlock(&args->inode->i_lock);
2180
2181         args->ld_private->ops = &layoutreturn_ops;
2182         args->ld_private->data = ff_args;
2183         return 0;
2184 out_nomem_free:
2185         kfree(ff_args);
2186 out_nomem:
2187         return -ENOMEM;
2188 }
2189
2190 #ifdef CONFIG_NFS_V4_2
2191 void
2192 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2193 {
2194         struct pnfs_layout_hdr *lo = lseg->pls_layout;
2195         struct nfs42_layout_error *errors;
2196         LIST_HEAD(head);
2197
2198         if (!nfs_server_capable(lo->plh_inode, NFS_CAP_LAYOUTERROR))
2199                 return;
2200         ff_layout_fetch_ds_ioerr(lo, &lseg->pls_range, &head, -1);
2201         if (list_empty(&head))
2202                 return;
2203
2204         errors = kmalloc_array(NFS42_LAYOUTERROR_MAX,
2205                         sizeof(*errors), GFP_NOFS);
2206         if (errors != NULL) {
2207                 const struct nfs4_ff_layout_ds_err *pos;
2208                 size_t n = 0;
2209
2210                 list_for_each_entry(pos, &head, list) {
2211                         errors[n].offset = pos->offset;
2212                         errors[n].length = pos->length;
2213                         nfs4_stateid_copy(&errors[n].stateid, &pos->stateid);
2214                         errors[n].errors[0].dev_id = pos->deviceid;
2215                         errors[n].errors[0].status = pos->status;
2216                         errors[n].errors[0].opnum = pos->opnum;
2217                         n++;
2218                         if (!list_is_last(&pos->list, &head) &&
2219                             n < NFS42_LAYOUTERROR_MAX)
2220                                 continue;
2221                         if (nfs42_proc_layouterror(lseg, errors, n) < 0)
2222                                 break;
2223                         n = 0;
2224                 }
2225                 kfree(errors);
2226         }
2227         ff_layout_free_ds_ioerr(&head);
2228 }
2229 #else
2230 void
2231 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2232 {
2233 }
2234 #endif
2235
2236 static int
2237 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2238 {
2239         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2240
2241         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2242 }
2243
2244 static size_t
2245 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2246                           const int buflen)
2247 {
2248         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2249         const struct in6_addr *addr = &sin6->sin6_addr;
2250
2251         /*
2252          * RFC 4291, Section 2.2.2
2253          *
2254          * Shorthanded ANY address
2255          */
2256         if (ipv6_addr_any(addr))
2257                 return snprintf(buf, buflen, "::");
2258
2259         /*
2260          * RFC 4291, Section 2.2.2
2261          *
2262          * Shorthanded loopback address
2263          */
2264         if (ipv6_addr_loopback(addr))
2265                 return snprintf(buf, buflen, "::1");
2266
2267         /*
2268          * RFC 4291, Section 2.2.3
2269          *
2270          * Special presentation address format for mapped v4
2271          * addresses.
2272          */
2273         if (ipv6_addr_v4mapped(addr))
2274                 return snprintf(buf, buflen, "::ffff:%pI4",
2275                                         &addr->s6_addr32[3]);
2276
2277         /*
2278          * RFC 4291, Section 2.2.1
2279          */
2280         return snprintf(buf, buflen, "%pI6c", addr);
2281 }
2282
2283 /* Derived from rpc_sockaddr2uaddr */
2284 static void
2285 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2286 {
2287         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2288         char portbuf[RPCBIND_MAXUADDRPLEN];
2289         char addrbuf[RPCBIND_MAXUADDRLEN];
2290         char *netid;
2291         unsigned short port;
2292         int len, netid_len;
2293         __be32 *p;
2294
2295         switch (sap->sa_family) {
2296         case AF_INET:
2297                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2298                         return;
2299                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2300                 netid = "tcp";
2301                 netid_len = 3;
2302                 break;
2303         case AF_INET6:
2304                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2305                         return;
2306                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2307                 netid = "tcp6";
2308                 netid_len = 4;
2309                 break;
2310         default:
2311                 /* we only support tcp and tcp6 */
2312                 WARN_ON_ONCE(1);
2313                 return;
2314         }
2315
2316         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2317         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2318
2319         p = xdr_reserve_space(xdr, 4 + netid_len);
2320         xdr_encode_opaque(p, netid, netid_len);
2321
2322         p = xdr_reserve_space(xdr, 4 + len);
2323         xdr_encode_opaque(p, addrbuf, len);
2324 }
2325
2326 static void
2327 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2328                          ktime_t t)
2329 {
2330         struct timespec64 ts;
2331         __be32 *p;
2332
2333         p = xdr_reserve_space(xdr, 12);
2334         ts = ktime_to_timespec64(t);
2335         p = xdr_encode_hyper(p, ts.tv_sec);
2336         *p++ = cpu_to_be32(ts.tv_nsec);
2337 }
2338
2339 static void
2340 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2341                             struct nfs4_ff_io_stat *stat)
2342 {
2343         __be32 *p;
2344
2345         p = xdr_reserve_space(xdr, 5 * 8);
2346         p = xdr_encode_hyper(p, stat->ops_requested);
2347         p = xdr_encode_hyper(p, stat->bytes_requested);
2348         p = xdr_encode_hyper(p, stat->ops_completed);
2349         p = xdr_encode_hyper(p, stat->bytes_completed);
2350         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2351         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2352         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2353 }
2354
2355 static void
2356 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2357                               const struct nfs42_layoutstat_devinfo *devinfo,
2358                               struct nfs4_ff_layout_mirror *mirror)
2359 {
2360         struct nfs4_pnfs_ds_addr *da;
2361         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2362         struct nfs_fh *fh = &mirror->fh_versions[0];
2363         __be32 *p;
2364
2365         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2366         dprintk("%s: DS %s: encoding address %s\n",
2367                 __func__, ds->ds_remotestr, da->da_remotestr);
2368         /* netaddr4 */
2369         ff_layout_encode_netaddr(xdr, da);
2370         /* nfs_fh4 */
2371         p = xdr_reserve_space(xdr, 4 + fh->size);
2372         xdr_encode_opaque(p, fh->data, fh->size);
2373         /* ff_io_latency4 read */
2374         spin_lock(&mirror->lock);
2375         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2376         /* ff_io_latency4 write */
2377         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2378         spin_unlock(&mirror->lock);
2379         /* nfstime4 */
2380         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2381         /* bool */
2382         p = xdr_reserve_space(xdr, 4);
2383         *p = cpu_to_be32(false);
2384 }
2385
2386 static void
2387 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2388                              const struct nfs4_xdr_opaque_data *opaque)
2389 {
2390         struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2391                         struct nfs42_layoutstat_devinfo, ld_private);
2392         __be32 *start;
2393
2394         /* layoutupdate length */
2395         start = xdr_reserve_space(xdr, 4);
2396         ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2397
2398         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2399 }
2400
2401 static void
2402 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2403 {
2404         struct nfs4_ff_layout_mirror *mirror = opaque->data;
2405
2406         ff_layout_put_mirror(mirror);
2407 }
2408
2409 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2410         .encode = ff_layout_encode_layoutstats,
2411         .free   = ff_layout_free_layoutstats,
2412 };
2413
2414 static int
2415 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2416                                struct nfs42_layoutstat_devinfo *devinfo,
2417                                int dev_limit)
2418 {
2419         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2420         struct nfs4_ff_layout_mirror *mirror;
2421         struct nfs4_deviceid_node *dev;
2422         int i = 0;
2423
2424         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2425                 if (i >= dev_limit)
2426                         break;
2427                 if (IS_ERR_OR_NULL(mirror->mirror_ds))
2428                         continue;
2429                 if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags))
2430                         continue;
2431                 /* mirror refcount put in cleanup_layoutstats */
2432                 if (!refcount_inc_not_zero(&mirror->ref))
2433                         continue;
2434                 dev = &mirror->mirror_ds->id_node;
2435                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2436                 devinfo->offset = 0;
2437                 devinfo->length = NFS4_MAX_UINT64;
2438                 spin_lock(&mirror->lock);
2439                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2440                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2441                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2442                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2443                 spin_unlock(&mirror->lock);
2444                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2445                 devinfo->ld_private.ops = &layoutstat_ops;
2446                 devinfo->ld_private.data = mirror;
2447
2448                 devinfo++;
2449                 i++;
2450         }
2451         return i;
2452 }
2453
2454 static int
2455 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2456 {
2457         struct nfs4_flexfile_layout *ff_layout;
2458         const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2459
2460         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2461         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
2462         if (!args->devinfo)
2463                 return -ENOMEM;
2464
2465         spin_lock(&args->inode->i_lock);
2466         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2467         args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2468                         &args->devinfo[0], dev_count);
2469         spin_unlock(&args->inode->i_lock);
2470         if (!args->num_dev) {
2471                 kfree(args->devinfo);
2472                 args->devinfo = NULL;
2473                 return -ENOENT;
2474         }
2475
2476         return 0;
2477 }
2478
2479 static int
2480 ff_layout_set_layoutdriver(struct nfs_server *server,
2481                 const struct nfs_fh *dummy)
2482 {
2483 #if IS_ENABLED(CONFIG_NFS_V4_2)
2484         server->caps |= NFS_CAP_LAYOUTSTATS;
2485 #endif
2486         return 0;
2487 }
2488
2489 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2490         .id                     = LAYOUT_FLEX_FILES,
2491         .name                   = "LAYOUT_FLEX_FILES",
2492         .owner                  = THIS_MODULE,
2493         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
2494         .max_layoutget_response = 4096, /* 1 page or so... */
2495         .set_layoutdriver       = ff_layout_set_layoutdriver,
2496         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2497         .free_layout_hdr        = ff_layout_free_layout_hdr,
2498         .alloc_lseg             = ff_layout_alloc_lseg,
2499         .free_lseg              = ff_layout_free_lseg,
2500         .add_lseg               = ff_layout_add_lseg,
2501         .pg_read_ops            = &ff_layout_pg_read_ops,
2502         .pg_write_ops           = &ff_layout_pg_write_ops,
2503         .get_ds_info            = ff_layout_get_ds_info,
2504         .free_deviceid_node     = ff_layout_free_deviceid_node,
2505         .mark_request_commit    = pnfs_layout_mark_request_commit,
2506         .clear_request_commit   = pnfs_generic_clear_request_commit,
2507         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2508         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2509         .commit_pagelist        = ff_layout_commit_pagelist,
2510         .read_pagelist          = ff_layout_read_pagelist,
2511         .write_pagelist         = ff_layout_write_pagelist,
2512         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2513         .prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2514         .sync                   = pnfs_nfs_generic_sync,
2515         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2516 };
2517
2518 static int __init nfs4flexfilelayout_init(void)
2519 {
2520         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2521                __func__);
2522         return pnfs_register_layoutdriver(&flexfilelayout_type);
2523 }
2524
2525 static void __exit nfs4flexfilelayout_exit(void)
2526 {
2527         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2528                __func__);
2529         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2530 }
2531
2532 MODULE_ALIAS("nfs-layouttype4-4");
2533
2534 MODULE_LICENSE("GPL");
2535 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2536
2537 module_init(nfs4flexfilelayout_init);
2538 module_exit(nfs4flexfilelayout_exit);
2539
2540 module_param(io_maxretrans, ushort, 0644);
2541 MODULE_PARM_DESC(io_maxretrans, "The  number of times the NFSv4.1 client "
2542                         "retries an I/O request before returning an error. ");