fs/nfsd/nfs4layouts.c

   1 /*
   2  * Copyright (c) 2014 Christoph Hellwig.
   3  */
   4 #include <linux/blkdev.h>
   5 #include <linux/kmod.h>
   6 #include <linux/file.h>
   7 #include <linux/jhash.h>
   8 #include <linux/sched.h>
   9 #include <linux/sunrpc/addr.h>
  10
  11 #include "pnfs.h"
  12 #include "netns.h"
  13 #include "trace.h"
  14
  15 #define NFSDDBG_FACILITY                NFSDDBG_PNFS
  16
  17 struct nfs4_layout {
  18         struct list_head                lo_perstate;
  19         struct nfs4_layout_stateid      *lo_state;
  20         struct nfsd4_layout_seg         lo_seg;
  21 };
  22
  23 static struct kmem_cache *nfs4_layout_cache;
  24 static struct kmem_cache *nfs4_layout_stateid_cache;
  25
  26 static const struct nfsd4_callback_ops nfsd4_cb_layout_ops;
  27 static const struct lock_manager_operations nfsd4_layouts_lm_ops;
  28
  29 const struct nfsd4_layout_ops *nfsd4_layout_ops[LAYOUT_TYPE_MAX] =  {
  30 #ifdef CONFIG_NFSD_BLOCKLAYOUT
  31         [LAYOUT_BLOCK_VOLUME]   = &bl_layout_ops,
  32 #endif
  33 #ifdef CONFIG_NFSD_SCSILAYOUT
  34         [LAYOUT_SCSI]           = &scsi_layout_ops,
  35 #endif
  36 };
  37
  38 /* pNFS device ID to export fsid mapping */
  39 #define DEVID_HASH_BITS 8
  40 #define DEVID_HASH_SIZE (1 << DEVID_HASH_BITS)
  41 #define DEVID_HASH_MASK (DEVID_HASH_SIZE - 1)
  42 static u64 nfsd_devid_seq = 1;
  43 static struct list_head nfsd_devid_hash[DEVID_HASH_SIZE];
  44 static DEFINE_SPINLOCK(nfsd_devid_lock);
  45
  46 static inline u32 devid_hashfn(u64 idx)
  47 {
  48         return jhash_2words(idx, idx >> 32, 0) & DEVID_HASH_MASK;
  49 }
  50
  51 static void
  52 nfsd4_alloc_devid_map(const struct svc_fh *fhp)
  53 {
  54         const struct knfsd_fh *fh = &fhp->fh_handle;
  55         size_t fsid_len = key_len(fh->fh_fsid_type);
  56         struct nfsd4_deviceid_map *map, *old;
  57         int i;
  58
  59         map = kzalloc(sizeof(*map) + fsid_len, GFP_KERNEL);
  60         if (!map)
  61                 return;
  62
  63         map->fsid_type = fh->fh_fsid_type;
  64         memcpy(&map->fsid, fh->fh_fsid, fsid_len);
  65
  66         spin_lock(&nfsd_devid_lock);
  67         if (fhp->fh_export->ex_devid_map)
  68                 goto out_unlock;
  69
  70         for (i = 0; i < DEVID_HASH_SIZE; i++) {
  71                 list_for_each_entry(old, &nfsd_devid_hash[i], hash) {
  72                         if (old->fsid_type != fh->fh_fsid_type)
  73                                 continue;
  74                         if (memcmp(old->fsid, fh->fh_fsid,
  75                                         key_len(old->fsid_type)))
  76                                 continue;
  77
  78                         fhp->fh_export->ex_devid_map = old;
  79                         goto out_unlock;
  80                 }
  81         }
  82
  83         map->idx = nfsd_devid_seq++;
  84         list_add_tail_rcu(&map->hash, &nfsd_devid_hash[devid_hashfn(map->idx)]);
  85         fhp->fh_export->ex_devid_map = map;
  86         map = NULL;
  87
  88 out_unlock:
  89         spin_unlock(&nfsd_devid_lock);
  90         kfree(map);
  91 }
  92
  93 struct nfsd4_deviceid_map *
  94 nfsd4_find_devid_map(int idx)
  95 {
  96         struct nfsd4_deviceid_map *map, *ret = NULL;
  97
  98         rcu_read_lock();
  99         list_for_each_entry_rcu(map, &nfsd_devid_hash[devid_hashfn(idx)], hash)
 100                 if (map->idx == idx)
 101                         ret = map;
 102         rcu_read_unlock();
 103
 104         return ret;
 105 }
 106
 107 int
 108 nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp,
 109                 u32 device_generation)
 110 {
 111         if (!fhp->fh_export->ex_devid_map) {
 112                 nfsd4_alloc_devid_map(fhp);
 113                 if (!fhp->fh_export->ex_devid_map)
 114                         return -ENOMEM;
 115         }
 116
 117         id->fsid_idx = fhp->fh_export->ex_devid_map->idx;
 118         id->generation = device_generation;
 119         id->pad = 0;
 120         return 0;
 121 }
 122
 123 void nfsd4_setup_layout_type(struct svc_export *exp)
 124 {
 125         struct super_block *sb = exp->ex_path.mnt->mnt_sb;
 126
 127         if (!(exp->ex_flags & NFSEXP_PNFS))
 128                 return;
 129
 130         /*
 131          * Check if the file system supports exporting a block-like layout.
 132          * If the block device supports reservations prefer the SCSI layout,
 133          * otherwise advertise the block layout.
 134          */
 135 #ifdef CONFIG_NFSD_BLOCKLAYOUT
 136         if (sb->s_export_op->get_uuid &&
 137             sb->s_export_op->map_blocks &&
 138             sb->s_export_op->commit_blocks)
 139                 exp->ex_layout_type = LAYOUT_BLOCK_VOLUME;
 140 #endif
 141 #ifdef CONFIG_NFSD_SCSILAYOUT
 142         /* overwrite block layout selection if needed */
 143         if (sb->s_export_op->map_blocks &&
 144             sb->s_export_op->commit_blocks &&
 145             sb->s_bdev && sb->s_bdev->bd_disk->fops->pr_ops)
 146                 exp->ex_layout_type = LAYOUT_SCSI;
 147 #endif
 148 }
 149
 150 static void
 151 nfsd4_free_layout_stateid(struct nfs4_stid *stid)
 152 {
 153         struct nfs4_layout_stateid *ls = layoutstateid(stid);
 154         struct nfs4_client *clp = ls->ls_stid.sc_client;
 155         struct nfs4_file *fp = ls->ls_stid.sc_file;
 156
 157         trace_layoutstate_free(&ls->ls_stid.sc_stateid);
 158
 159         spin_lock(&clp->cl_lock);
 160         list_del_init(&ls->ls_perclnt);
 161         spin_unlock(&clp->cl_lock);
 162
 163         spin_lock(&fp->fi_lock);
 164         list_del_init(&ls->ls_perfile);
 165         spin_unlock(&fp->fi_lock);
 166
 167         vfs_setlease(ls->ls_file, F_UNLCK, NULL, (void **)&ls);
 168         fput(ls->ls_file);
 169
 170         if (ls->ls_recalled)
 171                 atomic_dec(&ls->ls_stid.sc_file->fi_lo_recalls);
 172
 173         kmem_cache_free(nfs4_layout_stateid_cache, ls);
 174 }
 175
 176 static int
 177 nfsd4_layout_setlease(struct nfs4_layout_stateid *ls)
 178 {
 179         struct file_lock *fl;
 180         int status;
 181
 182         fl = locks_alloc_lock();
 183         if (!fl)
 184                 return -ENOMEM;
 185         locks_init_lock(fl);
 186         fl->fl_lmops = &nfsd4_layouts_lm_ops;
 187         fl->fl_flags = FL_LAYOUT;
 188         fl->fl_type = F_RDLCK;
 189         fl->fl_end = OFFSET_MAX;
 190         fl->fl_owner = ls;
 191         fl->fl_pid = current->tgid;
 192         fl->fl_file = ls->ls_file;
 193
 194         status = vfs_setlease(fl->fl_file, fl->fl_type, &fl, NULL);
 195         if (status) {
 196                 locks_free_lock(fl);
 197                 return status;
 198         }
 199         BUG_ON(fl != NULL);
 200         return 0;
 201 }
 202
 203 static struct nfs4_layout_stateid *
 204 nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
 205                 struct nfs4_stid *parent, u32 layout_type)
 206 {
 207         struct nfs4_client *clp = cstate->clp;
 208         struct nfs4_file *fp = parent->sc_file;
 209         struct nfs4_layout_stateid *ls;
 210         struct nfs4_stid *stp;
 211
 212         stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache);
 213         if (!stp)
 214                 return NULL;
 215         stp->sc_free = nfsd4_free_layout_stateid;
 216         get_nfs4_file(fp);
 217         stp->sc_file = fp;
 218
 219         ls = layoutstateid(stp);
 220         INIT_LIST_HEAD(&ls->ls_perclnt);
 221         INIT_LIST_HEAD(&ls->ls_perfile);
 222         spin_lock_init(&ls->ls_lock);
 223         INIT_LIST_HEAD(&ls->ls_layouts);
 224         mutex_init(&ls->ls_mutex);
 225         ls->ls_layout_type = layout_type;
 226         nfsd4_init_cb(&ls->ls_recall, clp, &nfsd4_cb_layout_ops,
 227                         NFSPROC4_CLNT_CB_LAYOUT);
 228
 229         if (parent->sc_type == NFS4_DELEG_STID)
 230                 ls->ls_file = get_file(fp->fi_deleg_file);
 231         else
 232                 ls->ls_file = find_any_file(fp);
 233         BUG_ON(!ls->ls_file);
 234
 235         if (nfsd4_layout_setlease(ls)) {
 236                 fput(ls->ls_file);
 237                 put_nfs4_file(fp);
 238                 kmem_cache_free(nfs4_layout_stateid_cache, ls);
 239                 return NULL;
 240         }
 241
 242         spin_lock(&clp->cl_lock);
 243         stp->sc_type = NFS4_LAYOUT_STID;
 244         list_add(&ls->ls_perclnt, &clp->cl_lo_states);
 245         spin_unlock(&clp->cl_lock);
 246
 247         spin_lock(&fp->fi_lock);
 248         list_add(&ls->ls_perfile, &fp->fi_lo_states);
 249         spin_unlock(&fp->fi_lock);
 250
 251         trace_layoutstate_alloc(&ls->ls_stid.sc_stateid);
 252         return ls;
 253 }
 254
 255 __be32
 256 nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
 257                 struct nfsd4_compound_state *cstate, stateid_t *stateid,
 258                 bool create, u32 layout_type, struct nfs4_layout_stateid **lsp)
 259 {
 260         struct nfs4_layout_stateid *ls;
 261         struct nfs4_stid *stid;
 262         unsigned char typemask = NFS4_LAYOUT_STID;
 263         __be32 status;
 264
 265         if (create)
 266                 typemask |= (NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID);
 267
 268         status = nfsd4_lookup_stateid(cstate, stateid, typemask, &stid,
 269                         net_generic(SVC_NET(rqstp), nfsd_net_id));
 270         if (status)
 271                 goto out;
 272
 273         if (!fh_match(&cstate->current_fh.fh_handle,
 274                       &stid->sc_file->fi_fhandle)) {
 275                 status = nfserr_bad_stateid;
 276                 goto out_put_stid;
 277         }
 278
 279         if (stid->sc_type != NFS4_LAYOUT_STID) {
 280                 ls = nfsd4_alloc_layout_stateid(cstate, stid, layout_type);
 281                 nfs4_put_stid(stid);
 282
 283                 status = nfserr_jukebox;
 284                 if (!ls)
 285                         goto out;
 286                 mutex_lock(&ls->ls_mutex);
 287         } else {
 288                 ls = container_of(stid, struct nfs4_layout_stateid, ls_stid);
 289
 290                 status = nfserr_bad_stateid;
 291                 mutex_lock(&ls->ls_mutex);
 292                 if (stateid->si_generation > stid->sc_stateid.si_generation)
 293                         goto out_unlock_stid;
 294                 if (layout_type != ls->ls_layout_type)
 295                         goto out_unlock_stid;
 296         }
 297
 298         *lsp = ls;
 299         return 0;
 300
 301 out_unlock_stid:
 302         mutex_unlock(&ls->ls_mutex);
 303 out_put_stid:
 304         nfs4_put_stid(stid);
 305 out:
 306         return status;
 307 }
 308
 309 static void
 310 nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
 311 {
 312         spin_lock(&ls->ls_lock);
 313         if (ls->ls_recalled)
 314                 goto out_unlock;
 315
 316         ls->ls_recalled = true;
 317         atomic_inc(&ls->ls_stid.sc_file->fi_lo_recalls);
 318         if (list_empty(&ls->ls_layouts))
 319                 goto out_unlock;
 320
 321         trace_layout_recall(&ls->ls_stid.sc_stateid);
 322
 323         atomic_inc(&ls->ls_stid.sc_count);
 324         nfsd4_run_cb(&ls->ls_recall);
 325
 326 out_unlock:
 327         spin_unlock(&ls->ls_lock);
 328 }
 329
 330 static inline u64
 331 layout_end(struct nfsd4_layout_seg *seg)
 332 {
 333         u64 end = seg->offset + seg->length;
 334         return end >= seg->offset ? end : NFS4_MAX_UINT64;
 335 }
 336
 337 static void
 338 layout_update_len(struct nfsd4_layout_seg *lo, u64 end)
 339 {
 340         if (end == NFS4_MAX_UINT64)
 341                 lo->length = NFS4_MAX_UINT64;
 342         else
 343                 lo->length = end - lo->offset;
 344 }
 345
 346 static bool
 347 layouts_overlapping(struct nfs4_layout *lo, struct nfsd4_layout_seg *s)
 348 {
 349         if (s->iomode != IOMODE_ANY && s->iomode != lo->lo_seg.iomode)
 350                 return false;
 351         if (layout_end(&lo->lo_seg) <= s->offset)
 352                 return false;
 353         if (layout_end(s) <= lo->lo_seg.offset)
 354                 return false;
 355         return true;
 356 }
 357
 358 static bool
 359 layouts_try_merge(struct nfsd4_layout_seg *lo, struct nfsd4_layout_seg *new)
 360 {
 361         if (lo->iomode != new->iomode)
 362                 return false;
 363         if (layout_end(new) < lo->offset)
 364                 return false;
 365         if (layout_end(lo) < new->offset)
 366                 return false;
 367
 368         lo->offset = min(lo->offset, new->offset);
 369         layout_update_len(lo, max(layout_end(lo), layout_end(new)));
 370         return true;
 371 }
 372
 373 static __be32
 374 nfsd4_recall_conflict(struct nfs4_layout_stateid *ls)
 375 {
 376         struct nfs4_file *fp = ls->ls_stid.sc_file;
 377         struct nfs4_layout_stateid *l, *n;
 378         __be32 nfserr = nfs_ok;
 379
 380         assert_spin_locked(&fp->fi_lock);
 381
 382         list_for_each_entry_safe(l, n, &fp->fi_lo_states, ls_perfile) {
 383                 if (l != ls) {
 384                         nfsd4_recall_file_layout(l);
 385                         nfserr = nfserr_recallconflict;
 386                 }
 387         }
 388
 389         return nfserr;
 390 }
 391
 392 __be32
 393 nfsd4_insert_layout(struct nfsd4_layoutget *lgp, struct nfs4_layout_stateid *ls)
 394 {
 395         struct nfsd4_layout_seg *seg = &lgp->lg_seg;
 396         struct nfs4_file *fp = ls->ls_stid.sc_file;
 397         struct nfs4_layout *lp, *new = NULL;
 398         __be32 nfserr;
 399
 400         spin_lock(&fp->fi_lock);
 401         nfserr = nfsd4_recall_conflict(ls);
 402         if (nfserr)
 403                 goto out;
 404         spin_lock(&ls->ls_lock);
 405         list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
 406                 if (layouts_try_merge(&lp->lo_seg, seg))
 407                         goto done;
 408         }
 409         spin_unlock(&ls->ls_lock);
 410         spin_unlock(&fp->fi_lock);
 411
 412         new = kmem_cache_alloc(nfs4_layout_cache, GFP_KERNEL);
 413         if (!new)
 414                 return nfserr_jukebox;
 415         memcpy(&new->lo_seg, seg, sizeof(lp->lo_seg));
 416         new->lo_state = ls;
 417
 418         spin_lock(&fp->fi_lock);
 419         nfserr = nfsd4_recall_conflict(ls);
 420         if (nfserr)
 421                 goto out;
 422         spin_lock(&ls->ls_lock);
 423         list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
 424                 if (layouts_try_merge(&lp->lo_seg, seg))
 425                         goto done;
 426         }
 427
 428         atomic_inc(&ls->ls_stid.sc_count);
 429         list_add_tail(&new->lo_perstate, &ls->ls_layouts);
 430         new = NULL;
 431 done:
 432         nfs4_inc_and_copy_stateid(&lgp->lg_sid, &ls->ls_stid);
 433         spin_unlock(&ls->ls_lock);
 434 out:
 435         spin_unlock(&fp->fi_lock);
 436         if (new)
 437                 kmem_cache_free(nfs4_layout_cache, new);
 438         return nfserr;
 439 }
 440
 441 static void
 442 nfsd4_free_layouts(struct list_head *reaplist)
 443 {
 444         while (!list_empty(reaplist)) {
 445                 struct nfs4_layout *lp = list_first_entry(reaplist,
 446                                 struct nfs4_layout, lo_perstate);
 447
 448                 list_del(&lp->lo_perstate);
 449                 nfs4_put_stid(&lp->lo_state->ls_stid);
 450                 kmem_cache_free(nfs4_layout_cache, lp);
 451         }
 452 }
 453
 454 static void
 455 nfsd4_return_file_layout(struct nfs4_layout *lp, struct nfsd4_layout_seg *seg,
 456                 struct list_head *reaplist)
 457 {
 458         struct nfsd4_layout_seg *lo = &lp->lo_seg;
 459         u64 end = layout_end(lo);
 460
 461         if (seg->offset <= lo->offset) {
 462                 if (layout_end(seg) >= end) {
 463                         list_move_tail(&lp->lo_perstate, reaplist);
 464                         return;
 465                 }
 466                 lo->offset = layout_end(seg);
 467         } else {
 468                 /* retain the whole layout segment on a split. */
 469                 if (layout_end(seg) < end) {
 470                         dprintk("%s: split not supported\n", __func__);
 471                         return;
 472                 }
 473                 end = seg->offset;
 474         }
 475
 476         layout_update_len(lo, end);
 477 }
 478
 479 __be32
 480 nfsd4_return_file_layouts(struct svc_rqst *rqstp,
 481                 struct nfsd4_compound_state *cstate,
 482                 struct nfsd4_layoutreturn *lrp)
 483 {
 484         struct nfs4_layout_stateid *ls;
 485         struct nfs4_layout *lp, *n;
 486         LIST_HEAD(reaplist);
 487         __be32 nfserr;
 488         int found = 0;
 489
 490         nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lrp->lr_sid,
 491                                                 false, lrp->lr_layout_type,
 492                                                 &ls);
 493         if (nfserr) {
 494                 trace_layout_return_lookup_fail(&lrp->lr_sid);
 495                 return nfserr;
 496         }
 497
 498         spin_lock(&ls->ls_lock);
 499         list_for_each_entry_safe(lp, n, &ls->ls_layouts, lo_perstate) {
 500                 if (layouts_overlapping(lp, &lrp->lr_seg)) {
 501                         nfsd4_return_file_layout(lp, &lrp->lr_seg, &reaplist);
 502                         found++;
 503                 }
 504         }
 505         if (!list_empty(&ls->ls_layouts)) {
 506                 if (found)
 507                         nfs4_inc_and_copy_stateid(&lrp->lr_sid, &ls->ls_stid);
 508                 lrp->lrs_present = 1;
 509         } else {
 510                 trace_layoutstate_unhash(&ls->ls_stid.sc_stateid);
 511                 nfs4_unhash_stid(&ls->ls_stid);
 512                 lrp->lrs_present = 0;
 513         }
 514         spin_unlock(&ls->ls_lock);
 515
 516         mutex_unlock(&ls->ls_mutex);
 517         nfs4_put_stid(&ls->ls_stid);
 518         nfsd4_free_layouts(&reaplist);
 519         return nfs_ok;
 520 }
 521
 522 __be32
 523 nfsd4_return_client_layouts(struct svc_rqst *rqstp,
 524                 struct nfsd4_compound_state *cstate,
 525                 struct nfsd4_layoutreturn *lrp)
 526 {
 527         struct nfs4_layout_stateid *ls, *n;
 528         struct nfs4_client *clp = cstate->clp;
 529         struct nfs4_layout *lp, *t;
 530         LIST_HEAD(reaplist);
 531
 532         lrp->lrs_present = 0;
 533
 534         spin_lock(&clp->cl_lock);
 535         list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt) {
 536                 if (ls->ls_layout_type != lrp->lr_layout_type)
 537                         continue;
 538
 539                 if (lrp->lr_return_type == RETURN_FSID &&
 540                     !fh_fsid_match(&ls->ls_stid.sc_file->fi_fhandle,
 541                                    &cstate->current_fh.fh_handle))
 542                         continue;
 543
 544                 spin_lock(&ls->ls_lock);
 545                 list_for_each_entry_safe(lp, t, &ls->ls_layouts, lo_perstate) {
 546                         if (lrp->lr_seg.iomode == IOMODE_ANY ||
 547                             lrp->lr_seg.iomode == lp->lo_seg.iomode)
 548                                 list_move_tail(&lp->lo_perstate, &reaplist);
 549                 }
 550                 spin_unlock(&ls->ls_lock);
 551         }
 552         spin_unlock(&clp->cl_lock);
 553
 554         nfsd4_free_layouts(&reaplist);
 555         return 0;
 556 }
 557
 558 static void
 559 nfsd4_return_all_layouts(struct nfs4_layout_stateid *ls,
 560                 struct list_head *reaplist)
 561 {
 562         spin_lock(&ls->ls_lock);
 563         list_splice_init(&ls->ls_layouts, reaplist);
 564         spin_unlock(&ls->ls_lock);
 565 }
 566
 567 void
 568 nfsd4_return_all_client_layouts(struct nfs4_client *clp)
 569 {
 570         struct nfs4_layout_stateid *ls, *n;
 571         LIST_HEAD(reaplist);
 572
 573         spin_lock(&clp->cl_lock);
 574         list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt)
 575                 nfsd4_return_all_layouts(ls, &reaplist);
 576         spin_unlock(&clp->cl_lock);
 577
 578         nfsd4_free_layouts(&reaplist);
 579 }
 580
 581 void
 582 nfsd4_return_all_file_layouts(struct nfs4_client *clp, struct nfs4_file *fp)
 583 {
 584         struct nfs4_layout_stateid *ls, *n;
 585         LIST_HEAD(reaplist);
 586
 587         spin_lock(&fp->fi_lock);
 588         list_for_each_entry_safe(ls, n, &fp->fi_lo_states, ls_perfile) {
 589                 if (ls->ls_stid.sc_client == clp)
 590                         nfsd4_return_all_layouts(ls, &reaplist);
 591         }
 592         spin_unlock(&fp->fi_lock);
 593
 594         nfsd4_free_layouts(&reaplist);
 595 }
 596
 597 static void
 598 nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
 599 {
 600         struct nfs4_client *clp = ls->ls_stid.sc_client;
 601         char addr_str[INET6_ADDRSTRLEN];
 602         static char *envp[] = {
 603                 "HOME=/",
 604                 "TERM=linux",
 605                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
 606                 NULL
 607         };
 608         char *argv[8];
 609         int error;
 610
 611         rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));
 612
 613         printk(KERN_WARNING
 614                 "nfsd: client %s failed to respond to layout recall. "
 615                 "  Fencing..\n", addr_str);
 616
 617         argv[0] = "/sbin/nfsd-recall-failed";
 618         argv[1] = addr_str;
 619         argv[2] = ls->ls_file->f_path.mnt->mnt_sb->s_id;
 620         argv[3] = NULL;
 621
 622         error = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
 623         if (error) {
 624                 printk(KERN_ERR "nfsd: fence failed for client %s: %d!\n",
 625                         addr_str, error);
 626         }
 627 }
 628
 629 static void
 630 nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)
 631 {
 632         struct nfs4_layout_stateid *ls =
 633                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
 634
 635         mutex_lock(&ls->ls_mutex);
 636         nfs4_inc_and_copy_stateid(&ls->ls_recall_sid, &ls->ls_stid);
 637         mutex_unlock(&ls->ls_mutex);
 638 }
 639
 640 static int
 641 nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
 642 {
 643         struct nfs4_layout_stateid *ls =
 644                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
 645         struct nfsd_net *nn;
 646         ktime_t now, cutoff;
 647         const struct nfsd4_layout_ops *ops;
 648         LIST_HEAD(reaplist);
 649
 650
 651         switch (task->tk_status) {
 652         case 0:
 653         case -NFS4ERR_DELAY:
 654                 /*
 655                  * Anything left? If not, then call it done. Note that we don't
 656                  * take the spinlock since this is an optimization and nothing
 657                  * should get added until the cb counter goes to zero.
 658                  */
 659                 if (list_empty(&ls->ls_layouts))
 660                         return 1;
 661
 662                 /* Poll the client until it's done with the layout */
 663                 now = ktime_get();
 664                 nn = net_generic(ls->ls_stid.sc_client->net, nfsd_net_id);
 665
 666                 /* Client gets 2 lease periods to return it */
 667                 cutoff = ktime_add_ns(task->tk_start,
 668                                          nn->nfsd4_lease * NSEC_PER_SEC * 2);
 669
 670                 if (ktime_before(now, cutoff)) {
 671                         rpc_delay(task, HZ/100); /* 10 mili-seconds */
 672                         return 0;
 673                 }
 674                 /* Fallthrough */
 675         case -NFS4ERR_NOMATCHING_LAYOUT:
 676                 trace_layout_recall_done(&ls->ls_stid.sc_stateid);
 677                 task->tk_status = 0;
 678                 return 1;
 679         default:
 680                 /*
 681                  * Unknown error or non-responding client, we'll need to fence.
 682                  */
 683                 trace_layout_recall_fail(&ls->ls_stid.sc_stateid);
 684
 685                 ops = nfsd4_layout_ops[ls->ls_layout_type];
 686                 if (ops->fence_client)
 687                         ops->fence_client(ls);
 688                 else
 689                         nfsd4_cb_layout_fail(ls);
 690                 return -1;
 691         }
 692 }
 693
 694 static void
 695 nfsd4_cb_layout_release(struct nfsd4_callback *cb)
 696 {
 697         struct nfs4_layout_stateid *ls =
 698                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
 699         LIST_HEAD(reaplist);
 700
 701         trace_layout_recall_release(&ls->ls_stid.sc_stateid);
 702
 703         nfsd4_return_all_layouts(ls, &reaplist);
 704         nfsd4_free_layouts(&reaplist);
 705         nfs4_put_stid(&ls->ls_stid);
 706 }
 707
 708 static const struct nfsd4_callback_ops nfsd4_cb_layout_ops = {
 709         .prepare        = nfsd4_cb_layout_prepare,
 710         .done           = nfsd4_cb_layout_done,
 711         .release        = nfsd4_cb_layout_release,
 712 };
 713
 714 static bool
 715 nfsd4_layout_lm_break(struct file_lock *fl)
 716 {
 717         /*
 718          * We don't want the locks code to timeout the lease for us;
 719          * we'll remove it ourself if a layout isn't returned
 720          * in time:
 721          */
 722         fl->fl_break_time = 0;
 723         nfsd4_recall_file_layout(fl->fl_owner);
 724         return false;
 725 }
 726
 727 static int
 728 nfsd4_layout_lm_change(struct file_lock *onlist, int arg,
 729                 struct list_head *dispose)
 730 {
 731         BUG_ON(!(arg & F_UNLCK));
 732         return lease_modify(onlist, arg, dispose);
 733 }
 734
 735 static const struct lock_manager_operations nfsd4_layouts_lm_ops = {
 736         .lm_break       = nfsd4_layout_lm_break,
 737         .lm_change      = nfsd4_layout_lm_change,
 738 };
 739
 740 int
 741 nfsd4_init_pnfs(void)
 742 {
 743         int i;
 744
 745         for (i = 0; i < DEVID_HASH_SIZE; i++)
 746                 INIT_LIST_HEAD(&nfsd_devid_hash[i]);
 747
 748         nfs4_layout_cache = kmem_cache_create("nfs4_layout",
 749                         sizeof(struct nfs4_layout), 0, 0, NULL);
 750         if (!nfs4_layout_cache)
 751                 return -ENOMEM;
 752
 753         nfs4_layout_stateid_cache = kmem_cache_create("nfs4_layout_stateid",
 754                         sizeof(struct nfs4_layout_stateid), 0, 0, NULL);
 755         if (!nfs4_layout_stateid_cache) {
 756                 kmem_cache_destroy(nfs4_layout_cache);
 757                 return -ENOMEM;
 758         }
 759         return 0;
 760 }
 761
 762 void
 763 nfsd4_exit_pnfs(void)
 764 {
 765         int i;
 766
 767         kmem_cache_destroy(nfs4_layout_cache);
 768         kmem_cache_destroy(nfs4_layout_stateid_cache);
 769
 770         for (i = 0; i < DEVID_HASH_SIZE; i++) {
 771                 struct nfsd4_deviceid_map *map, *n;
 772
 773                 list_for_each_entry_safe(map, n, &nfsd_devid_hash[i], hash)
 774                         kfree(map);
 775         }
 776 }