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