fs/nfs/flexfilelayout/flexfilelayout.c

   1 /*
   2  * Module for pnfs flexfile layout driver.
   3  *
   4  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   5  *
   6  * Tao Peng <bergwolf@primarydata.com>
   7  */
   8
   9 #include <linux/nfs_fs.h>
  10 #include <linux/nfs_page.h>
  11 #include <linux/module.h>
  12 #include <linux/sched/mm.h>
  13
  14 #include <linux/sunrpc/metrics.h>
  15
  16 #include "flexfilelayout.h"
  17 #include "../nfs4session.h"
  18 #include "../nfs4idmap.h"
  19 #include "../internal.h"
  20 #include "../delegation.h"
  21 #include "../nfs4trace.h"
  22 #include "../iostat.h"
  23 #include "../nfs.h"
  24 #include "../nfs42.h"
  25
  26 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  27
  28 #define FF_LAYOUT_POLL_RETRY_MAX     (15*HZ)
  29 #define FF_LAYOUTRETURN_MAXERR 20
  30
  31 static unsigned short io_maxretrans;
  32
  33 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
  34                 struct nfs_pgio_header *hdr);
  35 static int ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
  36                                struct nfs42_layoutstat_devinfo *devinfo,
  37                                int dev_limit);
  38 static void ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
  39                               const struct nfs42_layoutstat_devinfo *devinfo,
  40                               struct nfs4_ff_layout_mirror *mirror);
  41
  42 static struct pnfs_layout_hdr *
  43 ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
  44 {
  45         struct nfs4_flexfile_layout *ffl;
  46
  47         ffl = kzalloc(sizeof(*ffl), gfp_flags);
  48         if (ffl) {
  49                 INIT_LIST_HEAD(&ffl->error_list);
  50                 INIT_LIST_HEAD(&ffl->mirrors);
  51                 ffl->last_report_time = ktime_get();
  52                 return &ffl->generic_hdr;
  53         } else
  54                 return NULL;
  55 }
  56
  57 static void
  58 ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
  59 {
  60         struct nfs4_ff_layout_ds_err *err, *n;
  61
  62         list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
  63                                  list) {
  64                 list_del(&err->list);
  65                 kfree(err);
  66         }
  67         kfree(FF_LAYOUT_FROM_HDR(lo));
  68 }
  69
  70 static int decode_pnfs_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
  71 {
  72         __be32 *p;
  73
  74         p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
  75         if (unlikely(p == NULL))
  76                 return -ENOBUFS;
  77         stateid->type = NFS4_PNFS_DS_STATEID_TYPE;
  78         memcpy(stateid->data, p, NFS4_STATEID_SIZE);
  79         dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
  80                 p[0], p[1], p[2], p[3]);
  81         return 0;
  82 }
  83
  84 static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
  85 {
  86         __be32 *p;
  87
  88         p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
  89         if (unlikely(!p))
  90                 return -ENOBUFS;
  91         memcpy(devid, p, NFS4_DEVICEID4_SIZE);
  92         nfs4_print_deviceid(devid);
  93         return 0;
  94 }
  95
  96 static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
  97 {
  98         __be32 *p;
  99
 100         p = xdr_inline_decode(xdr, 4);
 101         if (unlikely(!p))
 102                 return -ENOBUFS;
 103         fh->size = be32_to_cpup(p++);
 104         if (fh->size > sizeof(struct nfs_fh)) {
 105                 printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
 106                        fh->size);
 107                 return -EOVERFLOW;
 108         }
 109         /* fh.data */
 110         p = xdr_inline_decode(xdr, fh->size);
 111         if (unlikely(!p))
 112                 return -ENOBUFS;
 113         memcpy(&fh->data, p, fh->size);
 114         dprintk("%s: fh len %d\n", __func__, fh->size);
 115
 116         return 0;
 117 }
 118
 119 /*
 120  * Currently only stringified uids and gids are accepted.
 121  * I.e., kerberos is not supported to the DSes, so no pricipals.
 122  *
 123  * That means that one common function will suffice, but when
 124  * principals are added, this should be split to accomodate
 125  * calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
 126  */
 127 static int
 128 decode_name(struct xdr_stream *xdr, u32 *id)
 129 {
 130         __be32 *p;
 131         int len;
 132
 133         /* opaque_length(4)*/
 134         p = xdr_inline_decode(xdr, 4);
 135         if (unlikely(!p))
 136                 return -ENOBUFS;
 137         len = be32_to_cpup(p++);
 138         if (len < 0)
 139                 return -EINVAL;
 140
 141         dprintk("%s: len %u\n", __func__, len);
 142
 143         /* opaque body */
 144         p = xdr_inline_decode(xdr, len);
 145         if (unlikely(!p))
 146                 return -ENOBUFS;
 147
 148         if (!nfs_map_string_to_numeric((char *)p, len, id))
 149                 return -EINVAL;
 150
 151         return 0;
 152 }
 153
 154 static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
 155                 const struct nfs4_ff_layout_mirror *m2)
 156 {
 157         int i, j;
 158
 159         if (m1->fh_versions_cnt != m2->fh_versions_cnt)
 160                 return false;
 161         for (i = 0; i < m1->fh_versions_cnt; i++) {
 162                 bool found_fh = false;
 163                 for (j = 0; j < m2->fh_versions_cnt; j++) {
 164                         if (nfs_compare_fh(&m1->fh_versions[i],
 165                                         &m2->fh_versions[j]) == 0) {
 166                                 found_fh = true;
 167                                 break;
 168                         }
 169                 }
 170                 if (!found_fh)
 171                         return false;
 172         }
 173         return true;
 174 }
 175
 176 static struct nfs4_ff_layout_mirror *
 177 ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
 178                 struct nfs4_ff_layout_mirror *mirror)
 179 {
 180         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
 181         struct nfs4_ff_layout_mirror *pos;
 182         struct inode *inode = lo->plh_inode;
 183
 184         spin_lock(&inode->i_lock);
 185         list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
 186                 if (memcmp(&mirror->devid, &pos->devid, sizeof(pos->devid)) != 0)
 187                         continue;
 188                 if (!ff_mirror_match_fh(mirror, pos))
 189                         continue;
 190                 if (refcount_inc_not_zero(&pos->ref)) {
 191                         spin_unlock(&inode->i_lock);
 192                         return pos;
 193                 }
 194         }
 195         list_add(&mirror->mirrors, &ff_layout->mirrors);
 196         mirror->layout = lo;
 197         spin_unlock(&inode->i_lock);
 198         return mirror;
 199 }
 200
 201 static void
 202 ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
 203 {
 204         struct inode *inode;
 205         if (mirror->layout == NULL)
 206                 return;
 207         inode = mirror->layout->plh_inode;
 208         spin_lock(&inode->i_lock);
 209         list_del(&mirror->mirrors);
 210         spin_unlock(&inode->i_lock);
 211         mirror->layout = NULL;
 212 }
 213
 214 static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
 215 {
 216         struct nfs4_ff_layout_mirror *mirror;
 217
 218         mirror = kzalloc(sizeof(*mirror), gfp_flags);
 219         if (mirror != NULL) {
 220                 spin_lock_init(&mirror->lock);
 221                 refcount_set(&mirror->ref, 1);
 222                 INIT_LIST_HEAD(&mirror->mirrors);
 223         }
 224         return mirror;
 225 }
 226
 227 static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
 228 {
 229         const struct cred       *cred;
 230
 231         ff_layout_remove_mirror(mirror);
 232         kfree(mirror->fh_versions);
 233         cred = rcu_access_pointer(mirror->ro_cred);
 234         put_cred(cred);
 235         cred = rcu_access_pointer(mirror->rw_cred);
 236         put_cred(cred);
 237         nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
 238         kfree(mirror);
 239 }
 240
 241 static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
 242 {
 243         if (mirror != NULL && refcount_dec_and_test(&mirror->ref))
 244                 ff_layout_free_mirror(mirror);
 245 }
 246
 247 static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
 248 {
 249         int i;
 250
 251         if (fls->mirror_array) {
 252                 for (i = 0; i < fls->mirror_array_cnt; i++) {
 253                         /* normally mirror_ds is freed in
 254                          * .free_deviceid_node but we still do it here
 255                          * for .alloc_lseg error path */
 256                         ff_layout_put_mirror(fls->mirror_array[i]);
 257                 }
 258                 kfree(fls->mirror_array);
 259                 fls->mirror_array = NULL;
 260         }
 261 }
 262
 263 static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
 264 {
 265         int ret = 0;
 266
 267         dprintk("--> %s\n", __func__);
 268
 269         /* FIXME: remove this check when layout segment support is added */
 270         if (lgr->range.offset != 0 ||
 271             lgr->range.length != NFS4_MAX_UINT64) {
 272                 dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
 273                         __func__);
 274                 ret = -EINVAL;
 275         }
 276
 277         dprintk("--> %s returns %d\n", __func__, ret);
 278         return ret;
 279 }
 280
 281 static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
 282 {
 283         if (fls) {
 284                 ff_layout_free_mirror_array(fls);
 285                 kfree(fls);
 286         }
 287 }
 288
 289 static bool
 290 ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
 291                 const struct pnfs_layout_range *l2)
 292 {
 293         u64 end1, end2;
 294
 295         if (l1->iomode != l2->iomode)
 296                 return l1->iomode != IOMODE_READ;
 297         end1 = pnfs_calc_offset_end(l1->offset, l1->length);
 298         end2 = pnfs_calc_offset_end(l2->offset, l2->length);
 299         if (end1 < l2->offset)
 300                 return false;
 301         if (end2 < l1->offset)
 302                 return true;
 303         return l2->offset <= l1->offset;
 304 }
 305
 306 static bool
 307 ff_lseg_merge(struct pnfs_layout_segment *new,
 308                 struct pnfs_layout_segment *old)
 309 {
 310         u64 new_end, old_end;
 311
 312         if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
 313                 return false;
 314         if (new->pls_range.iomode != old->pls_range.iomode)
 315                 return false;
 316         old_end = pnfs_calc_offset_end(old->pls_range.offset,
 317                         old->pls_range.length);
 318         if (old_end < new->pls_range.offset)
 319                 return false;
 320         new_end = pnfs_calc_offset_end(new->pls_range.offset,
 321                         new->pls_range.length);
 322         if (new_end < old->pls_range.offset)
 323                 return false;
 324
 325         /* Mergeable: copy info from 'old' to 'new' */
 326         if (new_end < old_end)
 327                 new_end = old_end;
 328         if (new->pls_range.offset < old->pls_range.offset)
 329                 new->pls_range.offset = old->pls_range.offset;
 330         new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
 331                         new_end);
 332         if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
 333                 set_bit(NFS_LSEG_ROC, &new->pls_flags);
 334         return true;
 335 }
 336
 337 static void
 338 ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
 339                 struct pnfs_layout_segment *lseg,
 340                 struct list_head *free_me)
 341 {
 342         pnfs_generic_layout_insert_lseg(lo, lseg,
 343                         ff_lseg_range_is_after,
 344                         ff_lseg_merge,
 345                         free_me);
 346 }
 347
 348 static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
 349 {
 350         int i, j;
 351
 352         for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
 353                 for (j = i + 1; j < fls->mirror_array_cnt; j++)
 354                         if (fls->mirror_array[i]->efficiency <
 355                             fls->mirror_array[j]->efficiency)
 356                                 swap(fls->mirror_array[i],
 357                                      fls->mirror_array[j]);
 358         }
 359 }
 360
 361 static struct pnfs_layout_segment *
 362 ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
 363                      struct nfs4_layoutget_res *lgr,
 364                      gfp_t gfp_flags)
 365 {
 366         struct pnfs_layout_segment *ret;
 367         struct nfs4_ff_layout_segment *fls = NULL;
 368         struct xdr_stream stream;
 369         struct xdr_buf buf;
 370         struct page *scratch;
 371         u64 stripe_unit;
 372         u32 mirror_array_cnt;
 373         __be32 *p;
 374         int i, rc;
 375
 376         dprintk("--> %s\n", __func__);
 377         scratch = alloc_page(gfp_flags);
 378         if (!scratch)
 379                 return ERR_PTR(-ENOMEM);
 380
 381         xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
 382                               lgr->layoutp->len);
 383         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 384
 385         /* stripe unit and mirror_array_cnt */
 386         rc = -EIO;
 387         p = xdr_inline_decode(&stream, 8 + 4);
 388         if (!p)
 389                 goto out_err_free;
 390
 391         p = xdr_decode_hyper(p, &stripe_unit);
 392         mirror_array_cnt = be32_to_cpup(p++);
 393         dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
 394                 stripe_unit, mirror_array_cnt);
 395
 396         if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
 397             mirror_array_cnt == 0)
 398                 goto out_err_free;
 399
 400         rc = -ENOMEM;
 401         fls = kzalloc(sizeof(*fls), gfp_flags);
 402         if (!fls)
 403                 goto out_err_free;
 404
 405         fls->mirror_array_cnt = mirror_array_cnt;
 406         fls->stripe_unit = stripe_unit;
 407         fls->mirror_array = kcalloc(fls->mirror_array_cnt,
 408                                     sizeof(fls->mirror_array[0]), gfp_flags);
 409         if (fls->mirror_array == NULL)
 410                 goto out_err_free;
 411
 412         for (i = 0; i < fls->mirror_array_cnt; i++) {
 413                 struct nfs4_ff_layout_mirror *mirror;
 414                 struct cred *kcred;
 415                 const struct cred __rcu *cred;
 416                 kuid_t uid;
 417                 kgid_t gid;
 418                 u32 ds_count, fh_count, id;
 419                 int j;
 420
 421                 rc = -EIO;
 422                 p = xdr_inline_decode(&stream, 4);
 423                 if (!p)
 424                         goto out_err_free;
 425                 ds_count = be32_to_cpup(p);
 426
 427                 /* FIXME: allow for striping? */
 428                 if (ds_count != 1)
 429                         goto out_err_free;
 430
 431                 fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
 432                 if (fls->mirror_array[i] == NULL) {
 433                         rc = -ENOMEM;
 434                         goto out_err_free;
 435                 }
 436
 437                 fls->mirror_array[i]->ds_count = ds_count;
 438
 439                 /* deviceid */
 440                 rc = decode_deviceid(&stream, &fls->mirror_array[i]->devid);
 441                 if (rc)
 442                         goto out_err_free;
 443
 444                 /* efficiency */
 445                 rc = -EIO;
 446                 p = xdr_inline_decode(&stream, 4);
 447                 if (!p)
 448                         goto out_err_free;
 449                 fls->mirror_array[i]->efficiency = be32_to_cpup(p);
 450
 451                 /* stateid */
 452                 rc = decode_pnfs_stateid(&stream, &fls->mirror_array[i]->stateid);
 453                 if (rc)
 454                         goto out_err_free;
 455
 456                 /* fh */
 457                 rc = -EIO;
 458                 p = xdr_inline_decode(&stream, 4);
 459                 if (!p)
 460                         goto out_err_free;
 461                 fh_count = be32_to_cpup(p);
 462
 463                 fls->mirror_array[i]->fh_versions =
 464                         kcalloc(fh_count, sizeof(struct nfs_fh),
 465                                 gfp_flags);
 466                 if (fls->mirror_array[i]->fh_versions == NULL) {
 467                         rc = -ENOMEM;
 468                         goto out_err_free;
 469                 }
 470
 471                 for (j = 0; j < fh_count; j++) {
 472                         rc = decode_nfs_fh(&stream,
 473                                            &fls->mirror_array[i]->fh_versions[j]);
 474                         if (rc)
 475                                 goto out_err_free;
 476                 }
 477
 478                 fls->mirror_array[i]->fh_versions_cnt = fh_count;
 479
 480                 /* user */
 481                 rc = decode_name(&stream, &id);
 482                 if (rc)
 483                         goto out_err_free;
 484
 485                 uid = make_kuid(&init_user_ns, id);
 486
 487                 /* group */
 488                 rc = decode_name(&stream, &id);
 489                 if (rc)
 490                         goto out_err_free;
 491
 492                 gid = make_kgid(&init_user_ns, id);
 493
 494                 if (gfp_flags & __GFP_FS)
 495                         kcred = prepare_kernel_cred(NULL);
 496                 else {
 497                         unsigned int nofs_flags = memalloc_nofs_save();
 498                         kcred = prepare_kernel_cred(NULL);
 499                         memalloc_nofs_restore(nofs_flags);
 500                 }
 501                 rc = -ENOMEM;
 502                 if (!kcred)
 503                         goto out_err_free;
 504                 kcred->fsuid = uid;
 505                 kcred->fsgid = gid;
 506                 cred = RCU_INITIALIZER(kcred);
 507
 508                 if (lgr->range.iomode == IOMODE_READ)
 509                         rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 510                 else
 511                         rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 512
 513                 mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
 514                 if (mirror != fls->mirror_array[i]) {
 515                         /* swap cred ptrs so free_mirror will clean up old */
 516                         if (lgr->range.iomode == IOMODE_READ) {
 517                                 cred = xchg(&mirror->ro_cred, cred);
 518                                 rcu_assign_pointer(fls->mirror_array[i]->ro_cred, cred);
 519                         } else {
 520                                 cred = xchg(&mirror->rw_cred, cred);
 521                                 rcu_assign_pointer(fls->mirror_array[i]->rw_cred, cred);
 522                         }
 523                         ff_layout_free_mirror(fls->mirror_array[i]);
 524                         fls->mirror_array[i] = mirror;
 525                 }
 526
 527                 dprintk("%s: iomode %s uid %u gid %u\n", __func__,
 528                         lgr->range.iomode == IOMODE_READ ? "READ" : "RW",
 529                         from_kuid(&init_user_ns, uid),
 530                         from_kgid(&init_user_ns, gid));
 531         }
 532
 533         p = xdr_inline_decode(&stream, 4);
 534         if (!p)
 535                 goto out_sort_mirrors;
 536         fls->flags = be32_to_cpup(p);
 537
 538         p = xdr_inline_decode(&stream, 4);
 539         if (!p)
 540                 goto out_sort_mirrors;
 541         for (i=0; i < fls->mirror_array_cnt; i++)
 542                 fls->mirror_array[i]->report_interval = be32_to_cpup(p);
 543
 544 out_sort_mirrors:
 545         ff_layout_sort_mirrors(fls);
 546         rc = ff_layout_check_layout(lgr);
 547         if (rc)
 548                 goto out_err_free;
 549         ret = &fls->generic_hdr;
 550         dprintk("<-- %s (success)\n", __func__);
 551 out_free_page:
 552         __free_page(scratch);
 553         return ret;
 554 out_err_free:
 555         _ff_layout_free_lseg(fls);
 556         ret = ERR_PTR(rc);
 557         dprintk("<-- %s (%d)\n", __func__, rc);
 558         goto out_free_page;
 559 }
 560
 561 static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
 562 {
 563         struct pnfs_layout_segment *lseg;
 564
 565         list_for_each_entry(lseg, &layout->plh_segs, pls_list)
 566                 if (lseg->pls_range.iomode == IOMODE_RW)
 567                         return true;
 568
 569         return false;
 570 }
 571
 572 static void
 573 ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
 574 {
 575         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 576
 577         dprintk("--> %s\n", __func__);
 578
 579         if (lseg->pls_range.iomode == IOMODE_RW) {
 580                 struct nfs4_flexfile_layout *ffl;
 581                 struct inode *inode;
 582
 583                 ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
 584                 inode = ffl->generic_hdr.plh_inode;
 585                 spin_lock(&inode->i_lock);
 586                 if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
 587                         ffl->commit_info.nbuckets = 0;
 588                         kfree(ffl->commit_info.buckets);
 589                         ffl->commit_info.buckets = NULL;
 590                 }
 591                 spin_unlock(&inode->i_lock);
 592         }
 593         _ff_layout_free_lseg(fls);
 594 }
 595
 596 /* Return 1 until we have multiple lsegs support */
 597 static int
 598 ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
 599 {
 600         return 1;
 601 }
 602
 603 static void
 604 nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 605 {
 606         /* first IO request? */
 607         if (atomic_inc_return(&timer->n_ops) == 1) {
 608                 timer->start_time = now;
 609         }
 610 }
 611
 612 static ktime_t
 613 nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
 614 {
 615         ktime_t start;
 616
 617         if (atomic_dec_return(&timer->n_ops) < 0)
 618                 WARN_ON_ONCE(1);
 619
 620         start = timer->start_time;
 621         timer->start_time = now;
 622         return ktime_sub(now, start);
 623 }
 624
 625 static bool
 626 nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 627                             struct nfs4_ff_layoutstat *layoutstat,
 628                             ktime_t now)
 629 {
 630         s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
 631         struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 632
 633         nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
 634         if (!mirror->start_time)
 635                 mirror->start_time = now;
 636         if (mirror->report_interval != 0)
 637                 report_interval = (s64)mirror->report_interval * 1000LL;
 638         else if (layoutstats_timer != 0)
 639                 report_interval = (s64)layoutstats_timer * 1000LL;
 640         if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
 641                         report_interval) {
 642                 ffl->last_report_time = now;
 643                 return true;
 644         }
 645
 646         return false;
 647 }
 648
 649 static void
 650 nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
 651                 __u64 requested)
 652 {
 653         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 654
 655         iostat->ops_requested++;
 656         iostat->bytes_requested += requested;
 657 }
 658
 659 static void
 660 nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
 661                 __u64 requested,
 662                 __u64 completed,
 663                 ktime_t time_completed,
 664                 ktime_t time_started)
 665 {
 666         struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
 667         ktime_t completion_time = ktime_sub(time_completed, time_started);
 668         ktime_t timer;
 669
 670         iostat->ops_completed++;
 671         iostat->bytes_completed += completed;
 672         iostat->bytes_not_delivered += requested - completed;
 673
 674         timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
 675         iostat->total_busy_time =
 676                         ktime_add(iostat->total_busy_time, timer);
 677         iostat->aggregate_completion_time =
 678                         ktime_add(iostat->aggregate_completion_time,
 679                                         completion_time);
 680 }
 681
 682 static void
 683 nfs4_ff_layout_stat_io_start_read(struct inode *inode,
 684                 struct nfs4_ff_layout_mirror *mirror,
 685                 __u64 requested, ktime_t now)
 686 {
 687         bool report;
 688
 689         spin_lock(&mirror->lock);
 690         report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
 691         nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
 692         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 693         spin_unlock(&mirror->lock);
 694
 695         if (report)
 696                 pnfs_report_layoutstat(inode, GFP_KERNEL);
 697 }
 698
 699 static void
 700 nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
 701                 struct nfs4_ff_layout_mirror *mirror,
 702                 __u64 requested,
 703                 __u64 completed)
 704 {
 705         spin_lock(&mirror->lock);
 706         nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
 707                         requested, completed,
 708                         ktime_get(), task->tk_start);
 709         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 710         spin_unlock(&mirror->lock);
 711 }
 712
 713 static void
 714 nfs4_ff_layout_stat_io_start_write(struct inode *inode,
 715                 struct nfs4_ff_layout_mirror *mirror,
 716                 __u64 requested, ktime_t now)
 717 {
 718         bool report;
 719
 720         spin_lock(&mirror->lock);
 721         report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
 722         nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
 723         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 724         spin_unlock(&mirror->lock);
 725
 726         if (report)
 727                 pnfs_report_layoutstat(inode, GFP_NOIO);
 728 }
 729
 730 static void
 731 nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
 732                 struct nfs4_ff_layout_mirror *mirror,
 733                 __u64 requested,
 734                 __u64 completed,
 735                 enum nfs3_stable_how committed)
 736 {
 737         if (committed == NFS_UNSTABLE)
 738                 requested = completed = 0;
 739
 740         spin_lock(&mirror->lock);
 741         nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
 742                         requested, completed, ktime_get(), task->tk_start);
 743         set_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags);
 744         spin_unlock(&mirror->lock);
 745 }
 746
 747 static int
 748 ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
 749                             struct nfs_commit_info *cinfo,
 750                             gfp_t gfp_flags)
 751 {
 752         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 753         struct pnfs_commit_bucket *buckets;
 754         int size;
 755
 756         if (cinfo->ds->nbuckets != 0) {
 757                 /* This assumes there is only one RW lseg per file.
 758                  * To support multiple lseg per file, we need to
 759                  * change struct pnfs_commit_bucket to allow dynamic
 760                  * increasing nbuckets.
 761                  */
 762                 return 0;
 763         }
 764
 765         size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
 766
 767         buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
 768                           gfp_flags);
 769         if (!buckets)
 770                 return -ENOMEM;
 771         else {
 772                 int i;
 773
 774                 spin_lock(&cinfo->inode->i_lock);
 775                 if (cinfo->ds->nbuckets != 0)
 776                         kfree(buckets);
 777                 else {
 778                         cinfo->ds->buckets = buckets;
 779                         cinfo->ds->nbuckets = size;
 780                         for (i = 0; i < size; i++) {
 781                                 INIT_LIST_HEAD(&buckets[i].written);
 782                                 INIT_LIST_HEAD(&buckets[i].committing);
 783                                 /* mark direct verifier as unset */
 784                                 buckets[i].direct_verf.committed =
 785                                         NFS_INVALID_STABLE_HOW;
 786                         }
 787                 }
 788                 spin_unlock(&cinfo->inode->i_lock);
 789                 return 0;
 790         }
 791 }
 792
 793 static void
 794 ff_layout_mark_ds_unreachable(struct pnfs_layout_segment *lseg, int idx)
 795 {
 796         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 797
 798         if (devid)
 799                 nfs4_mark_deviceid_unavailable(devid);
 800 }
 801
 802 static void
 803 ff_layout_mark_ds_reachable(struct pnfs_layout_segment *lseg, int idx)
 804 {
 805         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
 806
 807         if (devid)
 808                 nfs4_mark_deviceid_available(devid);
 809 }
 810
 811 static struct nfs4_pnfs_ds *
 812 ff_layout_choose_ds_for_read(struct pnfs_layout_segment *lseg,
 813                              int start_idx, int *best_idx,
 814                              bool check_device)
 815 {
 816         struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
 817         struct nfs4_ff_layout_mirror *mirror;
 818         struct nfs4_pnfs_ds *ds;
 819         bool fail_return = false;
 820         int idx;
 821
 822         /* mirrors are initially sorted by efficiency */
 823         for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
 824                 if (idx+1 == fls->mirror_array_cnt)
 825                         fail_return = !check_device;
 826
 827                 mirror = FF_LAYOUT_COMP(lseg, idx);
 828                 ds = nfs4_ff_layout_prepare_ds(lseg, mirror, fail_return);
 829                 if (!ds)
 830                         continue;
 831
 832                 if (check_device &&
 833                     nfs4_test_deviceid_unavailable(&mirror->mirror_ds->id_node))
 834                         continue;
 835
 836                 *best_idx = idx;
 837                 return ds;
 838         }
 839
 840         return NULL;
 841 }
 842
 843 static struct nfs4_pnfs_ds *
 844 ff_layout_choose_any_ds_for_read(struct pnfs_layout_segment *lseg,
 845                                  int start_idx, int *best_idx)
 846 {
 847         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, false);
 848 }
 849
 850 static struct nfs4_pnfs_ds *
 851 ff_layout_choose_valid_ds_for_read(struct pnfs_layout_segment *lseg,
 852                                    int start_idx, int *best_idx)
 853 {
 854         return ff_layout_choose_ds_for_read(lseg, start_idx, best_idx, true);
 855 }
 856
 857 static struct nfs4_pnfs_ds *
 858 ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
 859                                   int start_idx, int *best_idx)
 860 {
 861         struct nfs4_pnfs_ds *ds;
 862
 863         ds = ff_layout_choose_valid_ds_for_read(lseg, start_idx, best_idx);
 864         if (ds)
 865                 return ds;
 866         return ff_layout_choose_any_ds_for_read(lseg, start_idx, best_idx);
 867 }
 868
 869 static void
 870 ff_layout_pg_get_read(struct nfs_pageio_descriptor *pgio,
 871                       struct nfs_page *req,
 872                       bool strict_iomode)
 873 {
 874         pnfs_put_lseg(pgio->pg_lseg);
 875         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 876                                            nfs_req_openctx(req),
 877                                            0,
 878                                            NFS4_MAX_UINT64,
 879                                            IOMODE_READ,
 880                                            strict_iomode,
 881                                            GFP_KERNEL);
 882         if (IS_ERR(pgio->pg_lseg)) {
 883                 pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 884                 pgio->pg_lseg = NULL;
 885         }
 886 }
 887
 888 static void
 889 ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
 890                         struct nfs_page *req)
 891 {
 892         struct nfs_pgio_mirror *pgm;
 893         struct nfs4_ff_layout_mirror *mirror;
 894         struct nfs4_pnfs_ds *ds;
 895         int ds_idx;
 896
 897 retry:
 898         pnfs_generic_pg_check_layout(pgio);
 899         /* Use full layout for now */
 900         if (!pgio->pg_lseg) {
 901                 ff_layout_pg_get_read(pgio, req, false);
 902                 if (!pgio->pg_lseg)
 903                         goto out_nolseg;
 904         }
 905         if (ff_layout_avoid_read_on_rw(pgio->pg_lseg)) {
 906                 ff_layout_pg_get_read(pgio, req, true);
 907                 if (!pgio->pg_lseg)
 908                         goto out_nolseg;
 909         }
 910
 911         ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
 912         if (!ds) {
 913                 if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 914                         goto out_mds;
 915                 pnfs_put_lseg(pgio->pg_lseg);
 916                 pgio->pg_lseg = NULL;
 917                 /* Sleep for 1 second before retrying */
 918                 ssleep(1);
 919                 goto retry;
 920         }
 921
 922         mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 923
 924         pgio->pg_mirror_idx = ds_idx;
 925
 926         /* read always uses only one mirror - idx 0 for pgio layer */
 927         pgm = &pgio->pg_mirrors[0];
 928         pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
 929
 930         pgio->pg_maxretrans = io_maxretrans;
 931         return;
 932 out_nolseg:
 933         if (pgio->pg_error < 0)
 934                 return;
 935 out_mds:
 936         pnfs_put_lseg(pgio->pg_lseg);
 937         pgio->pg_lseg = NULL;
 938         nfs_pageio_reset_read_mds(pgio);
 939 }
 940
 941 static void
 942 ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 943                         struct nfs_page *req)
 944 {
 945         struct nfs4_ff_layout_mirror *mirror;
 946         struct nfs_pgio_mirror *pgm;
 947         struct nfs_commit_info cinfo;
 948         struct nfs4_pnfs_ds *ds;
 949         int i;
 950         int status;
 951
 952 retry:
 953         pnfs_generic_pg_check_layout(pgio);
 954         if (!pgio->pg_lseg) {
 955                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
 956                                                    nfs_req_openctx(req),
 957                                                    0,
 958                                                    NFS4_MAX_UINT64,
 959                                                    IOMODE_RW,
 960                                                    false,
 961                                                    GFP_NOFS);
 962                 if (IS_ERR(pgio->pg_lseg)) {
 963                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
 964                         pgio->pg_lseg = NULL;
 965                         return;
 966                 }
 967         }
 968         /* If no lseg, fall back to write through mds */
 969         if (pgio->pg_lseg == NULL)
 970                 goto out_mds;
 971
 972         nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
 973         status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
 974         if (status < 0)
 975                 goto out_mds;
 976
 977         /* Use a direct mapping of ds_idx to pgio mirror_idx */
 978         if (WARN_ON_ONCE(pgio->pg_mirror_count !=
 979             FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
 980                 goto out_mds;
 981
 982         for (i = 0; i < pgio->pg_mirror_count; i++) {
 983                 mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
 984                 ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, mirror, true);
 985                 if (!ds) {
 986                         if (!ff_layout_no_fallback_to_mds(pgio->pg_lseg))
 987                                 goto out_mds;
 988                         pnfs_put_lseg(pgio->pg_lseg);
 989                         pgio->pg_lseg = NULL;
 990                         /* Sleep for 1 second before retrying */
 991                         ssleep(1);
 992                         goto retry;
 993                 }
 994                 pgm = &pgio->pg_mirrors[i];
 995                 pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
 996         }
 997
 998         pgio->pg_maxretrans = io_maxretrans;
 999         return;
1000
1001 out_mds:
1002         pnfs_put_lseg(pgio->pg_lseg);
1003         pgio->pg_lseg = NULL;
1004         nfs_pageio_reset_write_mds(pgio);
1005 }
1006
1007 static unsigned int
1008 ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
1009                                     struct nfs_page *req)
1010 {
1011         if (!pgio->pg_lseg) {
1012                 pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1013                                                    nfs_req_openctx(req),
1014                                                    0,
1015                                                    NFS4_MAX_UINT64,
1016                                                    IOMODE_RW,
1017                                                    false,
1018                                                    GFP_NOFS);
1019                 if (IS_ERR(pgio->pg_lseg)) {
1020                         pgio->pg_error = PTR_ERR(pgio->pg_lseg);
1021                         pgio->pg_lseg = NULL;
1022                         goto out;
1023                 }
1024         }
1025         if (pgio->pg_lseg)
1026                 return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
1027
1028         /* no lseg means that pnfs is not in use, so no mirroring here */
1029         nfs_pageio_reset_write_mds(pgio);
1030 out:
1031         return 1;
1032 }
1033
1034 static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
1035         .pg_init = ff_layout_pg_init_read,
1036         .pg_test = pnfs_generic_pg_test,
1037         .pg_doio = pnfs_generic_pg_readpages,
1038         .pg_cleanup = pnfs_generic_pg_cleanup,
1039 };
1040
1041 static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
1042         .pg_init = ff_layout_pg_init_write,
1043         .pg_test = pnfs_generic_pg_test,
1044         .pg_doio = pnfs_generic_pg_writepages,
1045         .pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
1046         .pg_cleanup = pnfs_generic_pg_cleanup,
1047 };
1048
1049 static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
1050 {
1051         struct rpc_task *task = &hdr->task;
1052
1053         pnfs_layoutcommit_inode(hdr->inode, false);
1054
1055         if (retry_pnfs) {
1056                 dprintk("%s Reset task %5u for i/o through pNFS "
1057                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1058                         hdr->task.tk_pid,
1059                         hdr->inode->i_sb->s_id,
1060                         (unsigned long long)NFS_FILEID(hdr->inode),
1061                         hdr->args.count,
1062                         (unsigned long long)hdr->args.offset);
1063
1064                 hdr->completion_ops->reschedule_io(hdr);
1065                 return;
1066         }
1067
1068         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1069                 dprintk("%s Reset task %5u for i/o through MDS "
1070                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1071                         hdr->task.tk_pid,
1072                         hdr->inode->i_sb->s_id,
1073                         (unsigned long long)NFS_FILEID(hdr->inode),
1074                         hdr->args.count,
1075                         (unsigned long long)hdr->args.offset);
1076
1077                 task->tk_status = pnfs_write_done_resend_to_mds(hdr);
1078         }
1079 }
1080
1081 static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
1082 {
1083         struct rpc_task *task = &hdr->task;
1084
1085         pnfs_layoutcommit_inode(hdr->inode, false);
1086
1087         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1088                 dprintk("%s Reset task %5u for i/o through MDS "
1089                         "(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
1090                         hdr->task.tk_pid,
1091                         hdr->inode->i_sb->s_id,
1092                         (unsigned long long)NFS_FILEID(hdr->inode),
1093                         hdr->args.count,
1094                         (unsigned long long)hdr->args.offset);
1095
1096                 task->tk_status = pnfs_read_done_resend_to_mds(hdr);
1097         }
1098 }
1099
1100 static int ff_layout_async_handle_error_v4(struct rpc_task *task,
1101                                            struct nfs4_state *state,
1102                                            struct nfs_client *clp,
1103                                            struct pnfs_layout_segment *lseg,
1104                                            int idx)
1105 {
1106         struct pnfs_layout_hdr *lo = lseg->pls_layout;
1107         struct inode *inode = lo->plh_inode;
1108         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1109         struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
1110
1111         switch (task->tk_status) {
1112         case -NFS4ERR_BADSESSION:
1113         case -NFS4ERR_BADSLOT:
1114         case -NFS4ERR_BAD_HIGH_SLOT:
1115         case -NFS4ERR_DEADSESSION:
1116         case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
1117         case -NFS4ERR_SEQ_FALSE_RETRY:
1118         case -NFS4ERR_SEQ_MISORDERED:
1119                 dprintk("%s ERROR %d, Reset session. Exchangeid "
1120                         "flags 0x%x\n", __func__, task->tk_status,
1121                         clp->cl_exchange_flags);
1122                 nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
1123                 break;
1124         case -NFS4ERR_DELAY:
1125         case -NFS4ERR_GRACE:
1126                 rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
1127                 break;
1128         case -NFS4ERR_RETRY_UNCACHED_REP:
1129                 break;
1130         case -EAGAIN:
1131                 return -NFS4ERR_RESET_TO_PNFS;
1132         /* Invalidate Layout errors */
1133         case -NFS4ERR_PNFS_NO_LAYOUT:
1134         case -ESTALE:           /* mapped NFS4ERR_STALE */
1135         case -EBADHANDLE:       /* mapped NFS4ERR_BADHANDLE */
1136         case -EISDIR:           /* mapped NFS4ERR_ISDIR */
1137         case -NFS4ERR_FHEXPIRED:
1138         case -NFS4ERR_WRONG_TYPE:
1139                 dprintk("%s Invalid layout error %d\n", __func__,
1140                         task->tk_status);
1141                 /*
1142                  * Destroy layout so new i/o will get a new layout.
1143                  * Layout will not be destroyed until all current lseg
1144                  * references are put. Mark layout as invalid to resend failed
1145                  * i/o and all i/o waiting on the slot table to the MDS until
1146                  * layout is destroyed and a new valid layout is obtained.
1147                  */
1148                 pnfs_destroy_layout(NFS_I(inode));
1149                 rpc_wake_up(&tbl->slot_tbl_waitq);
1150                 goto reset;
1151         /* RPC connection errors */
1152         case -ECONNREFUSED:
1153         case -EHOSTDOWN:
1154         case -EHOSTUNREACH:
1155         case -ENETUNREACH:
1156         case -EIO:
1157         case -ETIMEDOUT:
1158         case -EPIPE:
1159                 dprintk("%s DS connection error %d\n", __func__,
1160                         task->tk_status);
1161                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1162                                 &devid->deviceid);
1163                 rpc_wake_up(&tbl->slot_tbl_waitq);
1164                 /* fall through */
1165         default:
1166                 if (ff_layout_avoid_mds_available_ds(lseg))
1167                         return -NFS4ERR_RESET_TO_PNFS;
1168 reset:
1169                 dprintk("%s Retry through MDS. Error %d\n", __func__,
1170                         task->tk_status);
1171                 return -NFS4ERR_RESET_TO_MDS;
1172         }
1173         task->tk_status = 0;
1174         return -EAGAIN;
1175 }
1176
1177 /* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
1178 static int ff_layout_async_handle_error_v3(struct rpc_task *task,
1179                                            struct pnfs_layout_segment *lseg,
1180                                            int idx)
1181 {
1182         struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
1183
1184         switch (task->tk_status) {
1185         /* File access problems. Don't mark the device as unavailable */
1186         case -EACCES:
1187         case -ESTALE:
1188         case -EISDIR:
1189         case -EBADHANDLE:
1190         case -ELOOP:
1191         case -ENOSPC:
1192         case -EAGAIN:
1193                 break;
1194         case -EJUKEBOX:
1195                 nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
1196                 goto out_retry;
1197         default:
1198                 dprintk("%s DS connection error %d\n", __func__,
1199                         task->tk_status);
1200                 nfs4_delete_deviceid(devid->ld, devid->nfs_client,
1201                                 &devid->deviceid);
1202         }
1203         /* FIXME: Need to prevent infinite looping here. */
1204         return -NFS4ERR_RESET_TO_PNFS;
1205 out_retry:
1206         task->tk_status = 0;
1207         rpc_restart_call_prepare(task);
1208         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
1209         return -EAGAIN;
1210 }
1211
1212 static int ff_layout_async_handle_error(struct rpc_task *task,
1213                                         struct nfs4_state *state,
1214                                         struct nfs_client *clp,
1215                                         struct pnfs_layout_segment *lseg,
1216                                         int idx)
1217 {
1218         int vers = clp->cl_nfs_mod->rpc_vers->number;
1219
1220         if (task->tk_status >= 0) {
1221                 ff_layout_mark_ds_reachable(lseg, idx);
1222                 return 0;
1223         }
1224
1225         /* Handle the case of an invalid layout segment */
1226         if (!pnfs_is_valid_lseg(lseg))
1227                 return -NFS4ERR_RESET_TO_PNFS;
1228
1229         switch (vers) {
1230         case 3:
1231                 return ff_layout_async_handle_error_v3(task, lseg, idx);
1232         case 4:
1233                 return ff_layout_async_handle_error_v4(task, state, clp,
1234                                                        lseg, idx);
1235         default:
1236                 /* should never happen */
1237                 WARN_ON_ONCE(1);
1238                 return 0;
1239         }
1240 }
1241
1242 static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
1243                                         int idx, u64 offset, u64 length,
1244                                         u32 status, int opnum, int error)
1245 {
1246         struct nfs4_ff_layout_mirror *mirror;
1247         int err;
1248
1249         if (status == 0) {
1250                 switch (error) {
1251                 case -ETIMEDOUT:
1252                 case -EPFNOSUPPORT:
1253                 case -EPROTONOSUPPORT:
1254                 case -EOPNOTSUPP:
1255                 case -ECONNREFUSED:
1256                 case -ECONNRESET:
1257                 case -EHOSTDOWN:
1258                 case -EHOSTUNREACH:
1259                 case -ENETUNREACH:
1260                 case -EADDRINUSE:
1261                 case -ENOBUFS:
1262                 case -EPIPE:
1263                 case -EPERM:
1264                         status = NFS4ERR_NXIO;
1265                         break;
1266                 case -EACCES:
1267                         status = NFS4ERR_ACCESS;
1268                         break;
1269                 default:
1270                         return;
1271                 }
1272         }
1273
1274         switch (status) {
1275         case NFS4ERR_DELAY:
1276         case NFS4ERR_GRACE:
1277                 return;
1278         default:
1279                 break;
1280         }
1281
1282         mirror = FF_LAYOUT_COMP(lseg, idx);
1283         err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
1284                                        mirror, offset, length, status, opnum,
1285                                        GFP_NOIO);
1286         if (status == NFS4ERR_NXIO)
1287                 ff_layout_mark_ds_unreachable(lseg, idx);
1288         pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
1289         dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
1290 }
1291
1292 /* NFS_PROTO call done callback routines */
1293 static int ff_layout_read_done_cb(struct rpc_task *task,
1294                                 struct nfs_pgio_header *hdr)
1295 {
1296         int new_idx = hdr->pgio_mirror_idx;
1297         int err;
1298
1299         trace_nfs4_pnfs_read(hdr, task->tk_status);
1300         if (task->tk_status < 0)
1301                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1302                                             hdr->args.offset, hdr->args.count,
1303                                             hdr->res.op_status, OP_READ,
1304                                             task->tk_status);
1305         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1306                                            hdr->ds_clp, hdr->lseg,
1307                                            hdr->pgio_mirror_idx);
1308
1309         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1310         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1311         switch (err) {
1312         case -NFS4ERR_RESET_TO_PNFS:
1313                 if (ff_layout_choose_best_ds_for_read(hdr->lseg,
1314                                         hdr->pgio_mirror_idx + 1,
1315                                         &new_idx))
1316                         goto out_layouterror;
1317                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1318                 return task->tk_status;
1319         case -NFS4ERR_RESET_TO_MDS:
1320                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1321                 return task->tk_status;
1322         case -EAGAIN:
1323                 goto out_eagain;
1324         }
1325
1326         return 0;
1327 out_layouterror:
1328         ff_layout_read_record_layoutstats_done(task, hdr);
1329         ff_layout_send_layouterror(hdr->lseg);
1330         hdr->pgio_mirror_idx = new_idx;
1331 out_eagain:
1332         rpc_restart_call_prepare(task);
1333         return -EAGAIN;
1334 }
1335
1336 static bool
1337 ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
1338 {
1339         return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
1340 }
1341
1342 /*
1343  * We reference the rpc_cred of the first WRITE that triggers the need for
1344  * a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
1345  * rfc5661 is not clear about which credential should be used.
1346  *
1347  * Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
1348  * to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
1349  * we always send layoutcommit after DS writes.
1350  */
1351 static void
1352 ff_layout_set_layoutcommit(struct inode *inode,
1353                 struct pnfs_layout_segment *lseg,
1354                 loff_t end_offset)
1355 {
1356         if (!ff_layout_need_layoutcommit(lseg))
1357                 return;
1358
1359         pnfs_set_layoutcommit(inode, lseg, end_offset);
1360         dprintk("%s inode %lu pls_end_pos %llu\n", __func__, inode->i_ino,
1361                 (unsigned long long) NFS_I(inode)->layout->plh_lwb);
1362 }
1363
1364 static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
1365                 struct nfs_pgio_header *hdr)
1366 {
1367         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1368                 return;
1369         nfs4_ff_layout_stat_io_start_read(hdr->inode,
1370                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1371                         hdr->args.count,
1372                         task->tk_start);
1373 }
1374
1375 static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
1376                 struct nfs_pgio_header *hdr)
1377 {
1378         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1379                 return;
1380         nfs4_ff_layout_stat_io_end_read(task,
1381                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1382                         hdr->args.count,
1383                         hdr->res.count);
1384         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1385 }
1386
1387 static int ff_layout_read_prepare_common(struct rpc_task *task,
1388                                          struct nfs_pgio_header *hdr)
1389 {
1390         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1391                 rpc_exit(task, -EIO);
1392                 return -EIO;
1393         }
1394
1395         ff_layout_read_record_layoutstats_start(task, hdr);
1396         return 0;
1397 }
1398
1399 /*
1400  * Call ops for the async read/write cases
1401  * In the case of dense layouts, the offset needs to be reset to its
1402  * original value.
1403  */
1404 static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
1405 {
1406         struct nfs_pgio_header *hdr = data;
1407
1408         if (ff_layout_read_prepare_common(task, hdr))
1409                 return;
1410
1411         rpc_call_start(task);
1412 }
1413
1414 static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
1415 {
1416         struct nfs_pgio_header *hdr = data;
1417
1418         if (nfs4_setup_sequence(hdr->ds_clp,
1419                                 &hdr->args.seq_args,
1420                                 &hdr->res.seq_res,
1421                                 task))
1422                 return;
1423
1424         ff_layout_read_prepare_common(task, hdr);
1425 }
1426
1427 static void
1428 ff_layout_io_prepare_transmit(struct rpc_task *task,
1429                 void *data)
1430 {
1431         struct nfs_pgio_header *hdr = data;
1432
1433         if (!pnfs_is_valid_lseg(hdr->lseg))
1434                 rpc_exit(task, -EAGAIN);
1435 }
1436
1437 static void ff_layout_read_call_done(struct rpc_task *task, void *data)
1438 {
1439         struct nfs_pgio_header *hdr = data;
1440
1441         dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
1442
1443         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1444             task->tk_status == 0) {
1445                 nfs4_sequence_done(task, &hdr->res.seq_res);
1446                 return;
1447         }
1448
1449         /* Note this may cause RPC to be resent */
1450         hdr->mds_ops->rpc_call_done(task, hdr);
1451 }
1452
1453 static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
1454 {
1455         struct nfs_pgio_header *hdr = data;
1456
1457         ff_layout_read_record_layoutstats_done(task, hdr);
1458         rpc_count_iostats_metrics(task,
1459             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
1460 }
1461
1462 static void ff_layout_read_release(void *data)
1463 {
1464         struct nfs_pgio_header *hdr = data;
1465
1466         ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
1467         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1468                 ff_layout_send_layouterror(hdr->lseg);
1469                 pnfs_read_resend_pnfs(hdr);
1470         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1471                 ff_layout_reset_read(hdr);
1472         pnfs_generic_rw_release(data);
1473 }
1474
1475
1476 static int ff_layout_write_done_cb(struct rpc_task *task,
1477                                 struct nfs_pgio_header *hdr)
1478 {
1479         loff_t end_offs = 0;
1480         int err;
1481
1482         trace_nfs4_pnfs_write(hdr, task->tk_status);
1483         if (task->tk_status < 0)
1484                 ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
1485                                             hdr->args.offset, hdr->args.count,
1486                                             hdr->res.op_status, OP_WRITE,
1487                                             task->tk_status);
1488         err = ff_layout_async_handle_error(task, hdr->args.context->state,
1489                                            hdr->ds_clp, hdr->lseg,
1490                                            hdr->pgio_mirror_idx);
1491
1492         clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1493         clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1494         switch (err) {
1495         case -NFS4ERR_RESET_TO_PNFS:
1496                 set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
1497                 return task->tk_status;
1498         case -NFS4ERR_RESET_TO_MDS:
1499                 set_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
1500                 return task->tk_status;
1501         case -EAGAIN:
1502                 return -EAGAIN;
1503         }
1504
1505         if (hdr->res.verf->committed == NFS_FILE_SYNC ||
1506             hdr->res.verf->committed == NFS_DATA_SYNC)
1507                 end_offs = hdr->mds_offset + (loff_t)hdr->res.count;
1508
1509         /* Note: if the write is unstable, don't set end_offs until commit */
1510         ff_layout_set_layoutcommit(hdr->inode, hdr->lseg, end_offs);
1511
1512         /* zero out fattr since we don't care DS attr at all */
1513         hdr->fattr.valid = 0;
1514         if (task->tk_status >= 0)
1515                 nfs_writeback_update_inode(hdr);
1516
1517         return 0;
1518 }
1519
1520 static int ff_layout_commit_done_cb(struct rpc_task *task,
1521                                      struct nfs_commit_data *data)
1522 {
1523         int err;
1524
1525         trace_nfs4_pnfs_commit_ds(data, task->tk_status);
1526         if (task->tk_status < 0)
1527                 ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
1528                                             data->args.offset, data->args.count,
1529                                             data->res.op_status, OP_COMMIT,
1530                                             task->tk_status);
1531         err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
1532                                            data->lseg, data->ds_commit_index);
1533
1534         switch (err) {
1535         case -NFS4ERR_RESET_TO_PNFS:
1536                 pnfs_generic_prepare_to_resend_writes(data);
1537                 return -EAGAIN;
1538         case -NFS4ERR_RESET_TO_MDS:
1539                 pnfs_generic_prepare_to_resend_writes(data);
1540                 return -EAGAIN;
1541         case -EAGAIN:
1542                 rpc_restart_call_prepare(task);
1543                 return -EAGAIN;
1544         }
1545
1546         ff_layout_set_layoutcommit(data->inode, data->lseg, data->lwb);
1547
1548         return 0;
1549 }
1550
1551 static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
1552                 struct nfs_pgio_header *hdr)
1553 {
1554         if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
1555                 return;
1556         nfs4_ff_layout_stat_io_start_write(hdr->inode,
1557                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1558                         hdr->args.count,
1559                         task->tk_start);
1560 }
1561
1562 static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
1563                 struct nfs_pgio_header *hdr)
1564 {
1565         if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
1566                 return;
1567         nfs4_ff_layout_stat_io_end_write(task,
1568                         FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
1569                         hdr->args.count, hdr->res.count,
1570                         hdr->res.verf->committed);
1571         set_bit(NFS_LSEG_LAYOUTRETURN, &hdr->lseg->pls_flags);
1572 }
1573
1574 static int ff_layout_write_prepare_common(struct rpc_task *task,
1575                                           struct nfs_pgio_header *hdr)
1576 {
1577         if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
1578                 rpc_exit(task, -EIO);
1579                 return -EIO;
1580         }
1581
1582         ff_layout_write_record_layoutstats_start(task, hdr);
1583         return 0;
1584 }
1585
1586 static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
1587 {
1588         struct nfs_pgio_header *hdr = data;
1589
1590         if (ff_layout_write_prepare_common(task, hdr))
1591                 return;
1592
1593         rpc_call_start(task);
1594 }
1595
1596 static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
1597 {
1598         struct nfs_pgio_header *hdr = data;
1599
1600         if (nfs4_setup_sequence(hdr->ds_clp,
1601                                 &hdr->args.seq_args,
1602                                 &hdr->res.seq_res,
1603                                 task))
1604                 return;
1605
1606         ff_layout_write_prepare_common(task, hdr);
1607 }
1608
1609 static void ff_layout_write_call_done(struct rpc_task *task, void *data)
1610 {
1611         struct nfs_pgio_header *hdr = data;
1612
1613         if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
1614             task->tk_status == 0) {
1615                 nfs4_sequence_done(task, &hdr->res.seq_res);
1616                 return;
1617         }
1618
1619         /* Note this may cause RPC to be resent */
1620         hdr->mds_ops->rpc_call_done(task, hdr);
1621 }
1622
1623 static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
1624 {
1625         struct nfs_pgio_header *hdr = data;
1626
1627         ff_layout_write_record_layoutstats_done(task, hdr);
1628         rpc_count_iostats_metrics(task,
1629             &NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
1630 }
1631
1632 static void ff_layout_write_release(void *data)
1633 {
1634         struct nfs_pgio_header *hdr = data;
1635
1636         ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
1637         if (test_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags)) {
1638                 ff_layout_send_layouterror(hdr->lseg);
1639                 ff_layout_reset_write(hdr, true);
1640         } else if (test_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags))
1641                 ff_layout_reset_write(hdr, false);
1642         pnfs_generic_rw_release(data);
1643 }
1644
1645 static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
1646                 struct nfs_commit_data *cdata)
1647 {
1648         if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
1649                 return;
1650         nfs4_ff_layout_stat_io_start_write(cdata->inode,
1651                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1652                         0, task->tk_start);
1653 }
1654
1655 static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
1656                 struct nfs_commit_data *cdata)
1657 {
1658         struct nfs_page *req;
1659         __u64 count = 0;
1660
1661         if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
1662                 return;
1663
1664         if (task->tk_status == 0) {
1665                 list_for_each_entry(req, &cdata->pages, wb_list)
1666                         count += req->wb_bytes;
1667         }
1668         nfs4_ff_layout_stat_io_end_write(task,
1669                         FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
1670                         count, count, NFS_FILE_SYNC);
1671         set_bit(NFS_LSEG_LAYOUTRETURN, &cdata->lseg->pls_flags);
1672 }
1673
1674 static void ff_layout_commit_prepare_common(struct rpc_task *task,
1675                 struct nfs_commit_data *cdata)
1676 {
1677         ff_layout_commit_record_layoutstats_start(task, cdata);
1678 }
1679
1680 static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
1681 {
1682         ff_layout_commit_prepare_common(task, data);
1683         rpc_call_start(task);
1684 }
1685
1686 static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
1687 {
1688         struct nfs_commit_data *wdata = data;
1689
1690         if (nfs4_setup_sequence(wdata->ds_clp,
1691                                 &wdata->args.seq_args,
1692                                 &wdata->res.seq_res,
1693                                 task))
1694                 return;
1695         ff_layout_commit_prepare_common(task, data);
1696 }
1697
1698 static void ff_layout_commit_done(struct rpc_task *task, void *data)
1699 {
1700         pnfs_generic_write_commit_done(task, data);
1701 }
1702
1703 static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
1704 {
1705         struct nfs_commit_data *cdata = data;
1706
1707         ff_layout_commit_record_layoutstats_done(task, cdata);
1708         rpc_count_iostats_metrics(task,
1709             &NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
1710 }
1711
1712 static void ff_layout_commit_release(void *data)
1713 {
1714         struct nfs_commit_data *cdata = data;
1715
1716         ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
1717         pnfs_generic_commit_release(data);
1718 }
1719
1720 static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
1721         .rpc_call_prepare = ff_layout_read_prepare_v3,
1722         .rpc_call_prepare_transmit = ff_layout_io_prepare_transmit,
1723         .rpc_call_done = ff_layout_read_call_done,
1724         .rpc_count_stats = ff_layout_read_count_stats,
1725         .rpc_release = ff_layout_read_release,
1726 };
1727
1728 static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
1729         .rpc_call_prepare = ff_layout_read_prepare_v4,
1730         .rpc_call_prepare_transmit = ff_layout_io_prepare_transmit,
1731         .rpc_call_done = ff_layout_read_call_done,
1732         .rpc_count_stats = ff_layout_read_count_stats,
1733         .rpc_release = ff_layout_read_release,
1734 };
1735
1736 static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
1737         .rpc_call_prepare = ff_layout_write_prepare_v3,
1738         .rpc_call_prepare_transmit = ff_layout_io_prepare_transmit,
1739         .rpc_call_done = ff_layout_write_call_done,
1740         .rpc_count_stats = ff_layout_write_count_stats,
1741         .rpc_release = ff_layout_write_release,
1742 };
1743
1744 static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
1745         .rpc_call_prepare = ff_layout_write_prepare_v4,
1746         .rpc_call_prepare_transmit = ff_layout_io_prepare_transmit,
1747         .rpc_call_done = ff_layout_write_call_done,
1748         .rpc_count_stats = ff_layout_write_count_stats,
1749         .rpc_release = ff_layout_write_release,
1750 };
1751
1752 static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
1753         .rpc_call_prepare = ff_layout_commit_prepare_v3,
1754         .rpc_call_done = ff_layout_commit_done,
1755         .rpc_count_stats = ff_layout_commit_count_stats,
1756         .rpc_release = ff_layout_commit_release,
1757 };
1758
1759 static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
1760         .rpc_call_prepare = ff_layout_commit_prepare_v4,
1761         .rpc_call_done = ff_layout_commit_done,
1762         .rpc_count_stats = ff_layout_commit_count_stats,
1763         .rpc_release = ff_layout_commit_release,
1764 };
1765
1766 static enum pnfs_try_status
1767 ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
1768 {
1769         struct pnfs_layout_segment *lseg = hdr->lseg;
1770         struct nfs4_pnfs_ds *ds;
1771         struct rpc_clnt *ds_clnt;
1772         struct nfs4_ff_layout_mirror *mirror;
1773         const struct cred *ds_cred;
1774         loff_t offset = hdr->args.offset;
1775         u32 idx = hdr->pgio_mirror_idx;
1776         int vers;
1777         struct nfs_fh *fh;
1778
1779         dprintk("--> %s ino %lu pgbase %u req %zu@%llu\n",
1780                 __func__, hdr->inode->i_ino,
1781                 hdr->args.pgbase, (size_t)hdr->args.count, offset);
1782
1783         mirror = FF_LAYOUT_COMP(lseg, idx);
1784         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, false);
1785         if (!ds)
1786                 goto out_failed;
1787
1788         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1789                                                    hdr->inode);
1790         if (IS_ERR(ds_clnt))
1791                 goto out_failed;
1792
1793         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1794         if (!ds_cred)
1795                 goto out_failed;
1796
1797         vers = nfs4_ff_layout_ds_version(mirror);
1798
1799         dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
1800                 ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count), vers);
1801
1802         hdr->pgio_done_cb = ff_layout_read_done_cb;
1803         refcount_inc(&ds->ds_clp->cl_count);
1804         hdr->ds_clp = ds->ds_clp;
1805         fh = nfs4_ff_layout_select_ds_fh(mirror);
1806         if (fh)
1807                 hdr->args.fh = fh;
1808
1809         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1810
1811         /*
1812          * Note that if we ever decide to split across DSes,
1813          * then we may need to handle dense-like offsets.
1814          */
1815         hdr->args.offset = offset;
1816         hdr->mds_offset = offset;
1817
1818         /* Perform an asynchronous read to ds */
1819         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1820                           vers == 3 ? &ff_layout_read_call_ops_v3 :
1821                                       &ff_layout_read_call_ops_v4,
1822                           0, RPC_TASK_SOFTCONN);
1823         put_cred(ds_cred);
1824         return PNFS_ATTEMPTED;
1825
1826 out_failed:
1827         if (ff_layout_avoid_mds_available_ds(lseg))
1828                 return PNFS_TRY_AGAIN;
1829         return PNFS_NOT_ATTEMPTED;
1830 }
1831
1832 /* Perform async writes. */
1833 static enum pnfs_try_status
1834 ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
1835 {
1836         struct pnfs_layout_segment *lseg = hdr->lseg;
1837         struct nfs4_pnfs_ds *ds;
1838         struct rpc_clnt *ds_clnt;
1839         struct nfs4_ff_layout_mirror *mirror;
1840         const struct cred *ds_cred;
1841         loff_t offset = hdr->args.offset;
1842         int vers;
1843         struct nfs_fh *fh;
1844         int idx = hdr->pgio_mirror_idx;
1845
1846         mirror = FF_LAYOUT_COMP(lseg, idx);
1847         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1848         if (!ds)
1849                 goto out_failed;
1850
1851         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1852                                                    hdr->inode);
1853         if (IS_ERR(ds_clnt))
1854                 goto out_failed;
1855
1856         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, hdr->cred);
1857         if (!ds_cred)
1858                 goto out_failed;
1859
1860         vers = nfs4_ff_layout_ds_version(mirror);
1861
1862         dprintk("%s ino %lu sync %d req %zu@%llu DS: %s cl_count %d vers %d\n",
1863                 __func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
1864                 offset, ds->ds_remotestr, refcount_read(&ds->ds_clp->cl_count),
1865                 vers);
1866
1867         hdr->pgio_done_cb = ff_layout_write_done_cb;
1868         refcount_inc(&ds->ds_clp->cl_count);
1869         hdr->ds_clp = ds->ds_clp;
1870         hdr->ds_commit_idx = idx;
1871         fh = nfs4_ff_layout_select_ds_fh(mirror);
1872         if (fh)
1873                 hdr->args.fh = fh;
1874
1875         nfs4_ff_layout_select_ds_stateid(mirror, &hdr->args.stateid);
1876
1877         /*
1878          * Note that if we ever decide to split across DSes,
1879          * then we may need to handle dense-like offsets.
1880          */
1881         hdr->args.offset = offset;
1882
1883         /* Perform an asynchronous write */
1884         nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
1885                           vers == 3 ? &ff_layout_write_call_ops_v3 :
1886                                       &ff_layout_write_call_ops_v4,
1887                           sync, RPC_TASK_SOFTCONN);
1888         put_cred(ds_cred);
1889         return PNFS_ATTEMPTED;
1890
1891 out_failed:
1892         if (ff_layout_avoid_mds_available_ds(lseg))
1893                 return PNFS_TRY_AGAIN;
1894         return PNFS_NOT_ATTEMPTED;
1895 }
1896
1897 static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1898 {
1899         return i;
1900 }
1901
1902 static struct nfs_fh *
1903 select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
1904 {
1905         struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
1906
1907         /* FIXME: Assume that there is only one NFS version available
1908          * for the DS.
1909          */
1910         return &flseg->mirror_array[i]->fh_versions[0];
1911 }
1912
1913 static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
1914 {
1915         struct pnfs_layout_segment *lseg = data->lseg;
1916         struct nfs4_pnfs_ds *ds;
1917         struct rpc_clnt *ds_clnt;
1918         struct nfs4_ff_layout_mirror *mirror;
1919         const struct cred *ds_cred;
1920         u32 idx;
1921         int vers, ret;
1922         struct nfs_fh *fh;
1923
1924         if (!lseg || !(pnfs_is_valid_lseg(lseg) ||
1925             test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags)))
1926                 goto out_err;
1927
1928         idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
1929         mirror = FF_LAYOUT_COMP(lseg, idx);
1930         ds = nfs4_ff_layout_prepare_ds(lseg, mirror, true);
1931         if (!ds)
1932                 goto out_err;
1933
1934         ds_clnt = nfs4_ff_find_or_create_ds_client(mirror, ds->ds_clp,
1935                                                    data->inode);
1936         if (IS_ERR(ds_clnt))
1937                 goto out_err;
1938
1939         ds_cred = ff_layout_get_ds_cred(mirror, &lseg->pls_range, data->cred);
1940         if (!ds_cred)
1941                 goto out_err;
1942
1943         vers = nfs4_ff_layout_ds_version(mirror);
1944
1945         dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
1946                 data->inode->i_ino, how, refcount_read(&ds->ds_clp->cl_count),
1947                 vers);
1948         data->commit_done_cb = ff_layout_commit_done_cb;
1949         data->cred = ds_cred;
1950         refcount_inc(&ds->ds_clp->cl_count);
1951         data->ds_clp = ds->ds_clp;
1952         fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
1953         if (fh)
1954                 data->args.fh = fh;
1955
1956         ret = nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
1957                                    vers == 3 ? &ff_layout_commit_call_ops_v3 :
1958                                                &ff_layout_commit_call_ops_v4,
1959                                    how, RPC_TASK_SOFTCONN);
1960         put_cred(ds_cred);
1961         return ret;
1962 out_err:
1963         pnfs_generic_prepare_to_resend_writes(data);
1964         pnfs_generic_commit_release(data);
1965         return -EAGAIN;
1966 }
1967
1968 static int
1969 ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
1970                            int how, struct nfs_commit_info *cinfo)
1971 {
1972         return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
1973                                             ff_layout_initiate_commit);
1974 }
1975
1976 static struct pnfs_ds_commit_info *
1977 ff_layout_get_ds_info(struct inode *inode)
1978 {
1979         struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
1980
1981         if (layout == NULL)
1982                 return NULL;
1983
1984         return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
1985 }
1986
1987 static void
1988 ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
1989 {
1990         nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
1991                                                   id_node));
1992 }
1993
1994 static int ff_layout_encode_ioerr(struct xdr_stream *xdr,
1995                                   const struct nfs4_layoutreturn_args *args,
1996                                   const struct nfs4_flexfile_layoutreturn_args *ff_args)
1997 {
1998         __be32 *start;
1999
2000         start = xdr_reserve_space(xdr, 4);
2001         if (unlikely(!start))
2002                 return -E2BIG;
2003
2004         *start = cpu_to_be32(ff_args->num_errors);
2005         /* This assume we always return _ALL_ layouts */
2006         return ff_layout_encode_ds_ioerr(xdr, &ff_args->errors);
2007 }
2008
2009 static void
2010 encode_opaque_fixed(struct xdr_stream *xdr, const void *buf, size_t len)
2011 {
2012         WARN_ON_ONCE(xdr_stream_encode_opaque_fixed(xdr, buf, len) < 0);
2013 }
2014
2015 static void
2016 ff_layout_encode_ff_iostat_head(struct xdr_stream *xdr,
2017                             const nfs4_stateid *stateid,
2018                             const struct nfs42_layoutstat_devinfo *devinfo)
2019 {
2020         __be32 *p;
2021
2022         p = xdr_reserve_space(xdr, 8 + 8);
2023         p = xdr_encode_hyper(p, devinfo->offset);
2024         p = xdr_encode_hyper(p, devinfo->length);
2025         encode_opaque_fixed(xdr, stateid->data, NFS4_STATEID_SIZE);
2026         p = xdr_reserve_space(xdr, 4*8);
2027         p = xdr_encode_hyper(p, devinfo->read_count);
2028         p = xdr_encode_hyper(p, devinfo->read_bytes);
2029         p = xdr_encode_hyper(p, devinfo->write_count);
2030         p = xdr_encode_hyper(p, devinfo->write_bytes);
2031         encode_opaque_fixed(xdr, devinfo->dev_id.data, NFS4_DEVICEID4_SIZE);
2032 }
2033
2034 static void
2035 ff_layout_encode_ff_iostat(struct xdr_stream *xdr,
2036                             const nfs4_stateid *stateid,
2037                             const struct nfs42_layoutstat_devinfo *devinfo)
2038 {
2039         ff_layout_encode_ff_iostat_head(xdr, stateid, devinfo);
2040         ff_layout_encode_ff_layoutupdate(xdr, devinfo,
2041                         devinfo->ld_private.data);
2042 }
2043
2044 /* report nothing for now */
2045 static void ff_layout_encode_iostats_array(struct xdr_stream *xdr,
2046                 const struct nfs4_layoutreturn_args *args,
2047                 struct nfs4_flexfile_layoutreturn_args *ff_args)
2048 {
2049         __be32 *p;
2050         int i;
2051
2052         p = xdr_reserve_space(xdr, 4);
2053         *p = cpu_to_be32(ff_args->num_dev);
2054         for (i = 0; i < ff_args->num_dev; i++)
2055                 ff_layout_encode_ff_iostat(xdr,
2056                                 &args->layout->plh_stateid,
2057                                 &ff_args->devinfo[i]);
2058 }
2059
2060 static void
2061 ff_layout_free_iostats_array(struct nfs42_layoutstat_devinfo *devinfo,
2062                 unsigned int num_entries)
2063 {
2064         unsigned int i;
2065
2066         for (i = 0; i < num_entries; i++) {
2067                 if (!devinfo[i].ld_private.ops)
2068                         continue;
2069                 if (!devinfo[i].ld_private.ops->free)
2070                         continue;
2071                 devinfo[i].ld_private.ops->free(&devinfo[i].ld_private);
2072         }
2073 }
2074
2075 static struct nfs4_deviceid_node *
2076 ff_layout_alloc_deviceid_node(struct nfs_server *server,
2077                               struct pnfs_device *pdev, gfp_t gfp_flags)
2078 {
2079         struct nfs4_ff_layout_ds *dsaddr;
2080
2081         dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
2082         if (!dsaddr)
2083                 return NULL;
2084         return &dsaddr->id_node;
2085 }
2086
2087 static void
2088 ff_layout_encode_layoutreturn(struct xdr_stream *xdr,
2089                 const void *voidargs,
2090                 const struct nfs4_xdr_opaque_data *ff_opaque)
2091 {
2092         const struct nfs4_layoutreturn_args *args = voidargs;
2093         struct nfs4_flexfile_layoutreturn_args *ff_args = ff_opaque->data;
2094         struct xdr_buf tmp_buf = {
2095                 .head = {
2096                         [0] = {
2097                                 .iov_base = page_address(ff_args->pages[0]),
2098                         },
2099                 },
2100                 .buflen = PAGE_SIZE,
2101         };
2102         struct xdr_stream tmp_xdr;
2103         __be32 *start;
2104
2105         dprintk("%s: Begin\n", __func__);
2106
2107         xdr_init_encode(&tmp_xdr, &tmp_buf, NULL, NULL);
2108
2109         ff_layout_encode_ioerr(&tmp_xdr, args, ff_args);
2110         ff_layout_encode_iostats_array(&tmp_xdr, args, ff_args);
2111
2112         start = xdr_reserve_space(xdr, 4);
2113         *start = cpu_to_be32(tmp_buf.len);
2114         xdr_write_pages(xdr, ff_args->pages, 0, tmp_buf.len);
2115
2116         dprintk("%s: Return\n", __func__);
2117 }
2118
2119 static void
2120 ff_layout_free_layoutreturn(struct nfs4_xdr_opaque_data *args)
2121 {
2122         struct nfs4_flexfile_layoutreturn_args *ff_args;
2123
2124         if (!args->data)
2125                 return;
2126         ff_args = args->data;
2127         args->data = NULL;
2128
2129         ff_layout_free_ds_ioerr(&ff_args->errors);
2130         ff_layout_free_iostats_array(ff_args->devinfo, ff_args->num_dev);
2131
2132         put_page(ff_args->pages[0]);
2133         kfree(ff_args);
2134 }
2135
2136 static const struct nfs4_xdr_opaque_ops layoutreturn_ops = {
2137         .encode = ff_layout_encode_layoutreturn,
2138         .free = ff_layout_free_layoutreturn,
2139 };
2140
2141 static int
2142 ff_layout_prepare_layoutreturn(struct nfs4_layoutreturn_args *args)
2143 {
2144         struct nfs4_flexfile_layoutreturn_args *ff_args;
2145         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(args->layout);
2146
2147         ff_args = kmalloc(sizeof(*ff_args), GFP_KERNEL);
2148         if (!ff_args)
2149                 goto out_nomem;
2150         ff_args->pages[0] = alloc_page(GFP_KERNEL);
2151         if (!ff_args->pages[0])
2152                 goto out_nomem_free;
2153
2154         INIT_LIST_HEAD(&ff_args->errors);
2155         ff_args->num_errors = ff_layout_fetch_ds_ioerr(args->layout,
2156                         &args->range, &ff_args->errors,
2157                         FF_LAYOUTRETURN_MAXERR);
2158
2159         spin_lock(&args->inode->i_lock);
2160         ff_args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2161                         &ff_args->devinfo[0], ARRAY_SIZE(ff_args->devinfo));
2162         spin_unlock(&args->inode->i_lock);
2163
2164         args->ld_private->ops = &layoutreturn_ops;
2165         args->ld_private->data = ff_args;
2166         return 0;
2167 out_nomem_free:
2168         kfree(ff_args);
2169 out_nomem:
2170         return -ENOMEM;
2171 }
2172
2173 #ifdef CONFIG_NFS_V4_2
2174 void
2175 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2176 {
2177         struct pnfs_layout_hdr *lo = lseg->pls_layout;
2178         struct nfs42_layout_error *errors;
2179         LIST_HEAD(head);
2180
2181         if (!nfs_server_capable(lo->plh_inode, NFS_CAP_LAYOUTERROR))
2182                 return;
2183         ff_layout_fetch_ds_ioerr(lo, &lseg->pls_range, &head, -1);
2184         if (list_empty(&head))
2185                 return;
2186
2187         errors = kmalloc_array(NFS42_LAYOUTERROR_MAX,
2188                         sizeof(*errors), GFP_NOFS);
2189         if (errors != NULL) {
2190                 const struct nfs4_ff_layout_ds_err *pos;
2191                 size_t n = 0;
2192
2193                 list_for_each_entry(pos, &head, list) {
2194                         errors[n].offset = pos->offset;
2195                         errors[n].length = pos->length;
2196                         nfs4_stateid_copy(&errors[n].stateid, &pos->stateid);
2197                         errors[n].errors[0].dev_id = pos->deviceid;
2198                         errors[n].errors[0].status = pos->status;
2199                         errors[n].errors[0].opnum = pos->opnum;
2200                         n++;
2201                         if (!list_is_last(&pos->list, &head) &&
2202                             n < NFS42_LAYOUTERROR_MAX)
2203                                 continue;
2204                         if (nfs42_proc_layouterror(lseg, errors, n) < 0)
2205                                 break;
2206                         n = 0;
2207                 }
2208                 kfree(errors);
2209         }
2210         ff_layout_free_ds_ioerr(&head);
2211 }
2212 #else
2213 void
2214 ff_layout_send_layouterror(struct pnfs_layout_segment *lseg)
2215 {
2216 }
2217 #endif
2218
2219 static int
2220 ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
2221 {
2222         const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
2223
2224         return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
2225 }
2226
2227 static size_t
2228 ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
2229                           const int buflen)
2230 {
2231         const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
2232         const struct in6_addr *addr = &sin6->sin6_addr;
2233
2234         /*
2235          * RFC 4291, Section 2.2.2
2236          *
2237          * Shorthanded ANY address
2238          */
2239         if (ipv6_addr_any(addr))
2240                 return snprintf(buf, buflen, "::");
2241
2242         /*
2243          * RFC 4291, Section 2.2.2
2244          *
2245          * Shorthanded loopback address
2246          */
2247         if (ipv6_addr_loopback(addr))
2248                 return snprintf(buf, buflen, "::1");
2249
2250         /*
2251          * RFC 4291, Section 2.2.3
2252          *
2253          * Special presentation address format for mapped v4
2254          * addresses.
2255          */
2256         if (ipv6_addr_v4mapped(addr))
2257                 return snprintf(buf, buflen, "::ffff:%pI4",
2258                                         &addr->s6_addr32[3]);
2259
2260         /*
2261          * RFC 4291, Section 2.2.1
2262          */
2263         return snprintf(buf, buflen, "%pI6c", addr);
2264 }
2265
2266 /* Derived from rpc_sockaddr2uaddr */
2267 static void
2268 ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
2269 {
2270         struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
2271         char portbuf[RPCBIND_MAXUADDRPLEN];
2272         char addrbuf[RPCBIND_MAXUADDRLEN];
2273         char *netid;
2274         unsigned short port;
2275         int len, netid_len;
2276         __be32 *p;
2277
2278         switch (sap->sa_family) {
2279         case AF_INET:
2280                 if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
2281                         return;
2282                 port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2283                 netid = "tcp";
2284                 netid_len = 3;
2285                 break;
2286         case AF_INET6:
2287                 if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
2288                         return;
2289                 port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
2290                 netid = "tcp6";
2291                 netid_len = 4;
2292                 break;
2293         default:
2294                 /* we only support tcp and tcp6 */
2295                 WARN_ON_ONCE(1);
2296                 return;
2297         }
2298
2299         snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
2300         len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
2301
2302         p = xdr_reserve_space(xdr, 4 + netid_len);
2303         xdr_encode_opaque(p, netid, netid_len);
2304
2305         p = xdr_reserve_space(xdr, 4 + len);
2306         xdr_encode_opaque(p, addrbuf, len);
2307 }
2308
2309 static void
2310 ff_layout_encode_nfstime(struct xdr_stream *xdr,
2311                          ktime_t t)
2312 {
2313         struct timespec64 ts;
2314         __be32 *p;
2315
2316         p = xdr_reserve_space(xdr, 12);
2317         ts = ktime_to_timespec64(t);
2318         p = xdr_encode_hyper(p, ts.tv_sec);
2319         *p++ = cpu_to_be32(ts.tv_nsec);
2320 }
2321
2322 static void
2323 ff_layout_encode_io_latency(struct xdr_stream *xdr,
2324                             struct nfs4_ff_io_stat *stat)
2325 {
2326         __be32 *p;
2327
2328         p = xdr_reserve_space(xdr, 5 * 8);
2329         p = xdr_encode_hyper(p, stat->ops_requested);
2330         p = xdr_encode_hyper(p, stat->bytes_requested);
2331         p = xdr_encode_hyper(p, stat->ops_completed);
2332         p = xdr_encode_hyper(p, stat->bytes_completed);
2333         p = xdr_encode_hyper(p, stat->bytes_not_delivered);
2334         ff_layout_encode_nfstime(xdr, stat->total_busy_time);
2335         ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
2336 }
2337
2338 static void
2339 ff_layout_encode_ff_layoutupdate(struct xdr_stream *xdr,
2340                               const struct nfs42_layoutstat_devinfo *devinfo,
2341                               struct nfs4_ff_layout_mirror *mirror)
2342 {
2343         struct nfs4_pnfs_ds_addr *da;
2344         struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
2345         struct nfs_fh *fh = &mirror->fh_versions[0];
2346         __be32 *p;
2347
2348         da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
2349         dprintk("%s: DS %s: encoding address %s\n",
2350                 __func__, ds->ds_remotestr, da->da_remotestr);
2351         /* netaddr4 */
2352         ff_layout_encode_netaddr(xdr, da);
2353         /* nfs_fh4 */
2354         p = xdr_reserve_space(xdr, 4 + fh->size);
2355         xdr_encode_opaque(p, fh->data, fh->size);
2356         /* ff_io_latency4 read */
2357         spin_lock(&mirror->lock);
2358         ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
2359         /* ff_io_latency4 write */
2360         ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
2361         spin_unlock(&mirror->lock);
2362         /* nfstime4 */
2363         ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
2364         /* bool */
2365         p = xdr_reserve_space(xdr, 4);
2366         *p = cpu_to_be32(false);
2367 }
2368
2369 static void
2370 ff_layout_encode_layoutstats(struct xdr_stream *xdr, const void *args,
2371                              const struct nfs4_xdr_opaque_data *opaque)
2372 {
2373         struct nfs42_layoutstat_devinfo *devinfo = container_of(opaque,
2374                         struct nfs42_layoutstat_devinfo, ld_private);
2375         __be32 *start;
2376
2377         /* layoutupdate length */
2378         start = xdr_reserve_space(xdr, 4);
2379         ff_layout_encode_ff_layoutupdate(xdr, devinfo, opaque->data);
2380
2381         *start = cpu_to_be32((xdr->p - start - 1) * 4);
2382 }
2383
2384 static void
2385 ff_layout_free_layoutstats(struct nfs4_xdr_opaque_data *opaque)
2386 {
2387         struct nfs4_ff_layout_mirror *mirror = opaque->data;
2388
2389         ff_layout_put_mirror(mirror);
2390 }
2391
2392 static const struct nfs4_xdr_opaque_ops layoutstat_ops = {
2393         .encode = ff_layout_encode_layoutstats,
2394         .free   = ff_layout_free_layoutstats,
2395 };
2396
2397 static int
2398 ff_layout_mirror_prepare_stats(struct pnfs_layout_hdr *lo,
2399                                struct nfs42_layoutstat_devinfo *devinfo,
2400                                int dev_limit)
2401 {
2402         struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
2403         struct nfs4_ff_layout_mirror *mirror;
2404         struct nfs4_deviceid_node *dev;
2405         int i = 0;
2406
2407         list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
2408                 if (i >= dev_limit)
2409                         break;
2410                 if (IS_ERR_OR_NULL(mirror->mirror_ds))
2411                         continue;
2412                 if (!test_and_clear_bit(NFS4_FF_MIRROR_STAT_AVAIL, &mirror->flags))
2413                         continue;
2414                 /* mirror refcount put in cleanup_layoutstats */
2415                 if (!refcount_inc_not_zero(&mirror->ref))
2416                         continue;
2417                 dev = &mirror->mirror_ds->id_node;
2418                 memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
2419                 devinfo->offset = 0;
2420                 devinfo->length = NFS4_MAX_UINT64;
2421                 spin_lock(&mirror->lock);
2422                 devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
2423                 devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
2424                 devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
2425                 devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
2426                 spin_unlock(&mirror->lock);
2427                 devinfo->layout_type = LAYOUT_FLEX_FILES;
2428                 devinfo->ld_private.ops = &layoutstat_ops;
2429                 devinfo->ld_private.data = mirror;
2430
2431                 devinfo++;
2432                 i++;
2433         }
2434         return i;
2435 }
2436
2437 static int
2438 ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
2439 {
2440         struct nfs4_flexfile_layout *ff_layout;
2441         const int dev_count = PNFS_LAYOUTSTATS_MAXDEV;
2442
2443         /* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
2444         args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
2445         if (!args->devinfo)
2446                 return -ENOMEM;
2447
2448         spin_lock(&args->inode->i_lock);
2449         ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
2450         args->num_dev = ff_layout_mirror_prepare_stats(&ff_layout->generic_hdr,
2451                         &args->devinfo[0], dev_count);
2452         spin_unlock(&args->inode->i_lock);
2453         if (!args->num_dev) {
2454                 kfree(args->devinfo);
2455                 args->devinfo = NULL;
2456                 return -ENOENT;
2457         }
2458
2459         return 0;
2460 }
2461
2462 static int
2463 ff_layout_set_layoutdriver(struct nfs_server *server,
2464                 const struct nfs_fh *dummy)
2465 {
2466 #if IS_ENABLED(CONFIG_NFS_V4_2)
2467         server->caps |= NFS_CAP_LAYOUTSTATS;
2468 #endif
2469         return 0;
2470 }
2471
2472 static struct pnfs_layoutdriver_type flexfilelayout_type = {
2473         .id                     = LAYOUT_FLEX_FILES,
2474         .name                   = "LAYOUT_FLEX_FILES",
2475         .owner                  = THIS_MODULE,
2476         .flags                  = PNFS_LAYOUTGET_ON_OPEN,
2477         .max_layoutget_response = 4096, /* 1 page or so... */
2478         .set_layoutdriver       = ff_layout_set_layoutdriver,
2479         .alloc_layout_hdr       = ff_layout_alloc_layout_hdr,
2480         .free_layout_hdr        = ff_layout_free_layout_hdr,
2481         .alloc_lseg             = ff_layout_alloc_lseg,
2482         .free_lseg              = ff_layout_free_lseg,
2483         .add_lseg               = ff_layout_add_lseg,
2484         .pg_read_ops            = &ff_layout_pg_read_ops,
2485         .pg_write_ops           = &ff_layout_pg_write_ops,
2486         .get_ds_info            = ff_layout_get_ds_info,
2487         .free_deviceid_node     = ff_layout_free_deviceid_node,
2488         .mark_request_commit    = pnfs_layout_mark_request_commit,
2489         .clear_request_commit   = pnfs_generic_clear_request_commit,
2490         .scan_commit_lists      = pnfs_generic_scan_commit_lists,
2491         .recover_commit_reqs    = pnfs_generic_recover_commit_reqs,
2492         .commit_pagelist        = ff_layout_commit_pagelist,
2493         .read_pagelist          = ff_layout_read_pagelist,
2494         .write_pagelist         = ff_layout_write_pagelist,
2495         .alloc_deviceid_node    = ff_layout_alloc_deviceid_node,
2496         .prepare_layoutreturn   = ff_layout_prepare_layoutreturn,
2497         .sync                   = pnfs_nfs_generic_sync,
2498         .prepare_layoutstats    = ff_layout_prepare_layoutstats,
2499 };
2500
2501 static int __init nfs4flexfilelayout_init(void)
2502 {
2503         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
2504                __func__);
2505         return pnfs_register_layoutdriver(&flexfilelayout_type);
2506 }
2507
2508 static void __exit nfs4flexfilelayout_exit(void)
2509 {
2510         printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
2511                __func__);
2512         pnfs_unregister_layoutdriver(&flexfilelayout_type);
2513 }
2514
2515 MODULE_ALIAS("nfs-layouttype4-4");
2516
2517 MODULE_LICENSE("GPL");
2518 MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
2519
2520 module_init(nfs4flexfilelayout_init);
2521 module_exit(nfs4flexfilelayout_exit);
2522
2523 module_param(io_maxretrans, ushort, 0644);
2524 MODULE_PARM_DESC(io_maxretrans, "The  number of times the NFSv4.1 client "
2525                         "retries an I/O request before returning an error. ");