GNU Linux-libre 4.9.318-gnu1
[releases.git] / 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_FLEXFILELAYOUT
31         [LAYOUT_FLEX_FILES]     = &ff_layout_ops,
32 #endif
33 #ifdef CONFIG_NFSD_BLOCKLAYOUT
34         [LAYOUT_BLOCK_VOLUME]   = &bl_layout_ops,
35 #endif
36 #ifdef CONFIG_NFSD_SCSILAYOUT
37         [LAYOUT_SCSI]           = &scsi_layout_ops,
38 #endif
39 };
40
41 /* pNFS device ID to export fsid mapping */
42 #define DEVID_HASH_BITS 8
43 #define DEVID_HASH_SIZE (1 << DEVID_HASH_BITS)
44 #define DEVID_HASH_MASK (DEVID_HASH_SIZE - 1)
45 static u64 nfsd_devid_seq = 1;
46 static struct list_head nfsd_devid_hash[DEVID_HASH_SIZE];
47 static DEFINE_SPINLOCK(nfsd_devid_lock);
48
49 static inline u32 devid_hashfn(u64 idx)
50 {
51         return jhash_2words(idx, idx >> 32, 0) & DEVID_HASH_MASK;
52 }
53
54 static void
55 nfsd4_alloc_devid_map(const struct svc_fh *fhp)
56 {
57         const struct knfsd_fh *fh = &fhp->fh_handle;
58         size_t fsid_len = key_len(fh->fh_fsid_type);
59         struct nfsd4_deviceid_map *map, *old;
60         int i;
61
62         map = kzalloc(sizeof(*map) + fsid_len, GFP_KERNEL);
63         if (!map)
64                 return;
65
66         map->fsid_type = fh->fh_fsid_type;
67         memcpy(&map->fsid, fh->fh_fsid, fsid_len);
68
69         spin_lock(&nfsd_devid_lock);
70         if (fhp->fh_export->ex_devid_map)
71                 goto out_unlock;
72
73         for (i = 0; i < DEVID_HASH_SIZE; i++) {
74                 list_for_each_entry(old, &nfsd_devid_hash[i], hash) {
75                         if (old->fsid_type != fh->fh_fsid_type)
76                                 continue;
77                         if (memcmp(old->fsid, fh->fh_fsid,
78                                         key_len(old->fsid_type)))
79                                 continue;
80
81                         fhp->fh_export->ex_devid_map = old;
82                         goto out_unlock;
83                 }
84         }
85
86         map->idx = nfsd_devid_seq++;
87         list_add_tail_rcu(&map->hash, &nfsd_devid_hash[devid_hashfn(map->idx)]);
88         fhp->fh_export->ex_devid_map = map;
89         map = NULL;
90
91 out_unlock:
92         spin_unlock(&nfsd_devid_lock);
93         kfree(map);
94 }
95
96 struct nfsd4_deviceid_map *
97 nfsd4_find_devid_map(int idx)
98 {
99         struct nfsd4_deviceid_map *map, *ret = NULL;
100
101         rcu_read_lock();
102         list_for_each_entry_rcu(map, &nfsd_devid_hash[devid_hashfn(idx)], hash)
103                 if (map->idx == idx)
104                         ret = map;
105         rcu_read_unlock();
106
107         return ret;
108 }
109
110 int
111 nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp,
112                 u32 device_generation)
113 {
114         if (!fhp->fh_export->ex_devid_map) {
115                 nfsd4_alloc_devid_map(fhp);
116                 if (!fhp->fh_export->ex_devid_map)
117                         return -ENOMEM;
118         }
119
120         id->fsid_idx = fhp->fh_export->ex_devid_map->idx;
121         id->generation = device_generation;
122         id->pad = 0;
123         return 0;
124 }
125
126 void nfsd4_setup_layout_type(struct svc_export *exp)
127 {
128 #if defined(CONFIG_NFSD_BLOCKLAYOUT) || defined(CONFIG_NFSD_SCSILAYOUT)
129         struct super_block *sb = exp->ex_path.mnt->mnt_sb;
130 #endif
131
132         if (!(exp->ex_flags & NFSEXP_PNFS))
133                 return;
134
135         /*
136          * If flex file is configured, use it by default. Otherwise
137          * check if the file system supports exporting a block-like layout.
138          * If the block device supports reservations prefer the SCSI layout,
139          * otherwise advertise the block layout.
140          */
141 #ifdef CONFIG_NFSD_FLEXFILELAYOUT
142         exp->ex_layout_types |= 1 << LAYOUT_FLEX_FILES;
143 #endif
144 #ifdef CONFIG_NFSD_BLOCKLAYOUT
145         /* overwrite flex file layout selection if needed */
146         if (sb->s_export_op->get_uuid &&
147             sb->s_export_op->map_blocks &&
148             sb->s_export_op->commit_blocks)
149                 exp->ex_layout_types |= 1 << LAYOUT_BLOCK_VOLUME;
150 #endif
151 #ifdef CONFIG_NFSD_SCSILAYOUT
152         /* overwrite block layout selection if needed */
153         if (sb->s_export_op->map_blocks &&
154             sb->s_export_op->commit_blocks &&
155             sb->s_bdev && sb->s_bdev->bd_disk->fops->pr_ops)
156                 exp->ex_layout_types |= 1 << LAYOUT_SCSI;
157 #endif
158 }
159
160 static void
161 nfsd4_free_layout_stateid(struct nfs4_stid *stid)
162 {
163         struct nfs4_layout_stateid *ls = layoutstateid(stid);
164         struct nfs4_client *clp = ls->ls_stid.sc_client;
165         struct nfs4_file *fp = ls->ls_stid.sc_file;
166
167         trace_layoutstate_free(&ls->ls_stid.sc_stateid);
168
169         spin_lock(&clp->cl_lock);
170         list_del_init(&ls->ls_perclnt);
171         spin_unlock(&clp->cl_lock);
172
173         spin_lock(&fp->fi_lock);
174         list_del_init(&ls->ls_perfile);
175         spin_unlock(&fp->fi_lock);
176
177         if (!nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
178                 vfs_setlease(ls->ls_file, F_UNLCK, NULL, (void **)&ls);
179         fput(ls->ls_file);
180
181         if (ls->ls_recalled)
182                 atomic_dec(&ls->ls_stid.sc_file->fi_lo_recalls);
183
184         kmem_cache_free(nfs4_layout_stateid_cache, ls);
185 }
186
187 static int
188 nfsd4_layout_setlease(struct nfs4_layout_stateid *ls)
189 {
190         struct file_lock *fl;
191         int status;
192
193         if (nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
194                 return 0;
195
196         fl = locks_alloc_lock();
197         if (!fl)
198                 return -ENOMEM;
199         locks_init_lock(fl);
200         fl->fl_lmops = &nfsd4_layouts_lm_ops;
201         fl->fl_flags = FL_LAYOUT;
202         fl->fl_type = F_RDLCK;
203         fl->fl_end = OFFSET_MAX;
204         fl->fl_owner = ls;
205         fl->fl_pid = current->tgid;
206         fl->fl_file = ls->ls_file;
207
208         status = vfs_setlease(fl->fl_file, fl->fl_type, &fl, NULL);
209         if (status) {
210                 locks_free_lock(fl);
211                 return status;
212         }
213         BUG_ON(fl != NULL);
214         return 0;
215 }
216
217 static struct nfs4_layout_stateid *
218 nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
219                 struct nfs4_stid *parent, u32 layout_type)
220 {
221         struct nfs4_client *clp = cstate->clp;
222         struct nfs4_file *fp = parent->sc_file;
223         struct nfs4_layout_stateid *ls;
224         struct nfs4_stid *stp;
225
226         stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache,
227                                         nfsd4_free_layout_stateid);
228         if (!stp)
229                 return NULL;
230
231         get_nfs4_file(fp);
232         stp->sc_file = fp;
233
234         ls = layoutstateid(stp);
235         INIT_LIST_HEAD(&ls->ls_perclnt);
236         INIT_LIST_HEAD(&ls->ls_perfile);
237         spin_lock_init(&ls->ls_lock);
238         INIT_LIST_HEAD(&ls->ls_layouts);
239         mutex_init(&ls->ls_mutex);
240         ls->ls_layout_type = layout_type;
241         nfsd4_init_cb(&ls->ls_recall, clp, &nfsd4_cb_layout_ops,
242                         NFSPROC4_CLNT_CB_LAYOUT);
243
244         if (parent->sc_type == NFS4_DELEG_STID)
245                 ls->ls_file = get_file(fp->fi_deleg_file);
246         else
247                 ls->ls_file = find_any_file(fp);
248         BUG_ON(!ls->ls_file);
249
250         if (nfsd4_layout_setlease(ls)) {
251                 fput(ls->ls_file);
252                 put_nfs4_file(fp);
253                 kmem_cache_free(nfs4_layout_stateid_cache, ls);
254                 return NULL;
255         }
256
257         spin_lock(&clp->cl_lock);
258         stp->sc_type = NFS4_LAYOUT_STID;
259         list_add(&ls->ls_perclnt, &clp->cl_lo_states);
260         spin_unlock(&clp->cl_lock);
261
262         spin_lock(&fp->fi_lock);
263         list_add(&ls->ls_perfile, &fp->fi_lo_states);
264         spin_unlock(&fp->fi_lock);
265
266         trace_layoutstate_alloc(&ls->ls_stid.sc_stateid);
267         return ls;
268 }
269
270 __be32
271 nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
272                 struct nfsd4_compound_state *cstate, stateid_t *stateid,
273                 bool create, u32 layout_type, struct nfs4_layout_stateid **lsp)
274 {
275         struct nfs4_layout_stateid *ls;
276         struct nfs4_stid *stid;
277         unsigned char typemask = NFS4_LAYOUT_STID;
278         __be32 status;
279
280         if (create)
281                 typemask |= (NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID);
282
283         status = nfsd4_lookup_stateid(cstate, stateid, typemask, &stid,
284                         net_generic(SVC_NET(rqstp), nfsd_net_id));
285         if (status)
286                 goto out;
287
288         if (!fh_match(&cstate->current_fh.fh_handle,
289                       &stid->sc_file->fi_fhandle)) {
290                 status = nfserr_bad_stateid;
291                 goto out_put_stid;
292         }
293
294         if (stid->sc_type != NFS4_LAYOUT_STID) {
295                 ls = nfsd4_alloc_layout_stateid(cstate, stid, layout_type);
296                 nfs4_put_stid(stid);
297
298                 status = nfserr_jukebox;
299                 if (!ls)
300                         goto out;
301                 mutex_lock(&ls->ls_mutex);
302         } else {
303                 ls = container_of(stid, struct nfs4_layout_stateid, ls_stid);
304
305                 status = nfserr_bad_stateid;
306                 mutex_lock(&ls->ls_mutex);
307                 if (nfsd4_stateid_generation_after(stateid, &stid->sc_stateid))
308                         goto out_unlock_stid;
309                 if (layout_type != ls->ls_layout_type)
310                         goto out_unlock_stid;
311         }
312
313         *lsp = ls;
314         return 0;
315
316 out_unlock_stid:
317         mutex_unlock(&ls->ls_mutex);
318 out_put_stid:
319         nfs4_put_stid(stid);
320 out:
321         return status;
322 }
323
324 static void
325 nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
326 {
327         spin_lock(&ls->ls_lock);
328         if (ls->ls_recalled)
329                 goto out_unlock;
330
331         ls->ls_recalled = true;
332         atomic_inc(&ls->ls_stid.sc_file->fi_lo_recalls);
333         if (list_empty(&ls->ls_layouts))
334                 goto out_unlock;
335
336         trace_layout_recall(&ls->ls_stid.sc_stateid);
337
338         atomic_inc(&ls->ls_stid.sc_count);
339         nfsd4_run_cb(&ls->ls_recall);
340
341 out_unlock:
342         spin_unlock(&ls->ls_lock);
343 }
344
345 static inline u64
346 layout_end(struct nfsd4_layout_seg *seg)
347 {
348         u64 end = seg->offset + seg->length;
349         return end >= seg->offset ? end : NFS4_MAX_UINT64;
350 }
351
352 static void
353 layout_update_len(struct nfsd4_layout_seg *lo, u64 end)
354 {
355         if (end == NFS4_MAX_UINT64)
356                 lo->length = NFS4_MAX_UINT64;
357         else
358                 lo->length = end - lo->offset;
359 }
360
361 static bool
362 layouts_overlapping(struct nfs4_layout *lo, struct nfsd4_layout_seg *s)
363 {
364         if (s->iomode != IOMODE_ANY && s->iomode != lo->lo_seg.iomode)
365                 return false;
366         if (layout_end(&lo->lo_seg) <= s->offset)
367                 return false;
368         if (layout_end(s) <= lo->lo_seg.offset)
369                 return false;
370         return true;
371 }
372
373 static bool
374 layouts_try_merge(struct nfsd4_layout_seg *lo, struct nfsd4_layout_seg *new)
375 {
376         if (lo->iomode != new->iomode)
377                 return false;
378         if (layout_end(new) < lo->offset)
379                 return false;
380         if (layout_end(lo) < new->offset)
381                 return false;
382
383         lo->offset = min(lo->offset, new->offset);
384         layout_update_len(lo, max(layout_end(lo), layout_end(new)));
385         return true;
386 }
387
388 static __be32
389 nfsd4_recall_conflict(struct nfs4_layout_stateid *ls)
390 {
391         struct nfs4_file *fp = ls->ls_stid.sc_file;
392         struct nfs4_layout_stateid *l, *n;
393         __be32 nfserr = nfs_ok;
394
395         assert_spin_locked(&fp->fi_lock);
396
397         list_for_each_entry_safe(l, n, &fp->fi_lo_states, ls_perfile) {
398                 if (l != ls) {
399                         nfsd4_recall_file_layout(l);
400                         nfserr = nfserr_recallconflict;
401                 }
402         }
403
404         return nfserr;
405 }
406
407 __be32
408 nfsd4_insert_layout(struct nfsd4_layoutget *lgp, struct nfs4_layout_stateid *ls)
409 {
410         struct nfsd4_layout_seg *seg = &lgp->lg_seg;
411         struct nfs4_file *fp = ls->ls_stid.sc_file;
412         struct nfs4_layout *lp, *new = NULL;
413         __be32 nfserr;
414
415         spin_lock(&fp->fi_lock);
416         nfserr = nfsd4_recall_conflict(ls);
417         if (nfserr)
418                 goto out;
419         spin_lock(&ls->ls_lock);
420         list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
421                 if (layouts_try_merge(&lp->lo_seg, seg))
422                         goto done;
423         }
424         spin_unlock(&ls->ls_lock);
425         spin_unlock(&fp->fi_lock);
426
427         new = kmem_cache_alloc(nfs4_layout_cache, GFP_KERNEL);
428         if (!new)
429                 return nfserr_jukebox;
430         memcpy(&new->lo_seg, seg, sizeof(lp->lo_seg));
431         new->lo_state = ls;
432
433         spin_lock(&fp->fi_lock);
434         nfserr = nfsd4_recall_conflict(ls);
435         if (nfserr)
436                 goto out;
437         spin_lock(&ls->ls_lock);
438         list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
439                 if (layouts_try_merge(&lp->lo_seg, seg))
440                         goto done;
441         }
442
443         atomic_inc(&ls->ls_stid.sc_count);
444         list_add_tail(&new->lo_perstate, &ls->ls_layouts);
445         new = NULL;
446 done:
447         nfs4_inc_and_copy_stateid(&lgp->lg_sid, &ls->ls_stid);
448         spin_unlock(&ls->ls_lock);
449 out:
450         spin_unlock(&fp->fi_lock);
451         if (new)
452                 kmem_cache_free(nfs4_layout_cache, new);
453         return nfserr;
454 }
455
456 static void
457 nfsd4_free_layouts(struct list_head *reaplist)
458 {
459         while (!list_empty(reaplist)) {
460                 struct nfs4_layout *lp = list_first_entry(reaplist,
461                                 struct nfs4_layout, lo_perstate);
462
463                 list_del(&lp->lo_perstate);
464                 nfs4_put_stid(&lp->lo_state->ls_stid);
465                 kmem_cache_free(nfs4_layout_cache, lp);
466         }
467 }
468
469 static void
470 nfsd4_return_file_layout(struct nfs4_layout *lp, struct nfsd4_layout_seg *seg,
471                 struct list_head *reaplist)
472 {
473         struct nfsd4_layout_seg *lo = &lp->lo_seg;
474         u64 end = layout_end(lo);
475
476         if (seg->offset <= lo->offset) {
477                 if (layout_end(seg) >= end) {
478                         list_move_tail(&lp->lo_perstate, reaplist);
479                         return;
480                 }
481                 lo->offset = layout_end(seg);
482         } else {
483                 /* retain the whole layout segment on a split. */
484                 if (layout_end(seg) < end) {
485                         dprintk("%s: split not supported\n", __func__);
486                         return;
487                 }
488                 end = seg->offset;
489         }
490
491         layout_update_len(lo, end);
492 }
493
494 __be32
495 nfsd4_return_file_layouts(struct svc_rqst *rqstp,
496                 struct nfsd4_compound_state *cstate,
497                 struct nfsd4_layoutreturn *lrp)
498 {
499         struct nfs4_layout_stateid *ls;
500         struct nfs4_layout *lp, *n;
501         LIST_HEAD(reaplist);
502         __be32 nfserr;
503         int found = 0;
504
505         nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lrp->lr_sid,
506                                                 false, lrp->lr_layout_type,
507                                                 &ls);
508         if (nfserr) {
509                 trace_layout_return_lookup_fail(&lrp->lr_sid);
510                 return nfserr;
511         }
512
513         spin_lock(&ls->ls_lock);
514         list_for_each_entry_safe(lp, n, &ls->ls_layouts, lo_perstate) {
515                 if (layouts_overlapping(lp, &lrp->lr_seg)) {
516                         nfsd4_return_file_layout(lp, &lrp->lr_seg, &reaplist);
517                         found++;
518                 }
519         }
520         if (!list_empty(&ls->ls_layouts)) {
521                 if (found)
522                         nfs4_inc_and_copy_stateid(&lrp->lr_sid, &ls->ls_stid);
523                 lrp->lrs_present = 1;
524         } else {
525                 trace_layoutstate_unhash(&ls->ls_stid.sc_stateid);
526                 nfs4_unhash_stid(&ls->ls_stid);
527                 lrp->lrs_present = 0;
528         }
529         spin_unlock(&ls->ls_lock);
530
531         mutex_unlock(&ls->ls_mutex);
532         nfs4_put_stid(&ls->ls_stid);
533         nfsd4_free_layouts(&reaplist);
534         return nfs_ok;
535 }
536
537 __be32
538 nfsd4_return_client_layouts(struct svc_rqst *rqstp,
539                 struct nfsd4_compound_state *cstate,
540                 struct nfsd4_layoutreturn *lrp)
541 {
542         struct nfs4_layout_stateid *ls, *n;
543         struct nfs4_client *clp = cstate->clp;
544         struct nfs4_layout *lp, *t;
545         LIST_HEAD(reaplist);
546
547         lrp->lrs_present = 0;
548
549         spin_lock(&clp->cl_lock);
550         list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt) {
551                 if (ls->ls_layout_type != lrp->lr_layout_type)
552                         continue;
553
554                 if (lrp->lr_return_type == RETURN_FSID &&
555                     !fh_fsid_match(&ls->ls_stid.sc_file->fi_fhandle,
556                                    &cstate->current_fh.fh_handle))
557                         continue;
558
559                 spin_lock(&ls->ls_lock);
560                 list_for_each_entry_safe(lp, t, &ls->ls_layouts, lo_perstate) {
561                         if (lrp->lr_seg.iomode == IOMODE_ANY ||
562                             lrp->lr_seg.iomode == lp->lo_seg.iomode)
563                                 list_move_tail(&lp->lo_perstate, &reaplist);
564                 }
565                 spin_unlock(&ls->ls_lock);
566         }
567         spin_unlock(&clp->cl_lock);
568
569         nfsd4_free_layouts(&reaplist);
570         return 0;
571 }
572
573 static void
574 nfsd4_return_all_layouts(struct nfs4_layout_stateid *ls,
575                 struct list_head *reaplist)
576 {
577         spin_lock(&ls->ls_lock);
578         list_splice_init(&ls->ls_layouts, reaplist);
579         spin_unlock(&ls->ls_lock);
580 }
581
582 void
583 nfsd4_return_all_client_layouts(struct nfs4_client *clp)
584 {
585         struct nfs4_layout_stateid *ls, *n;
586         LIST_HEAD(reaplist);
587
588         spin_lock(&clp->cl_lock);
589         list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt)
590                 nfsd4_return_all_layouts(ls, &reaplist);
591         spin_unlock(&clp->cl_lock);
592
593         nfsd4_free_layouts(&reaplist);
594 }
595
596 void
597 nfsd4_return_all_file_layouts(struct nfs4_client *clp, struct nfs4_file *fp)
598 {
599         struct nfs4_layout_stateid *ls, *n;
600         LIST_HEAD(reaplist);
601
602         spin_lock(&fp->fi_lock);
603         list_for_each_entry_safe(ls, n, &fp->fi_lo_states, ls_perfile) {
604                 if (ls->ls_stid.sc_client == clp)
605                         nfsd4_return_all_layouts(ls, &reaplist);
606         }
607         spin_unlock(&fp->fi_lock);
608
609         nfsd4_free_layouts(&reaplist);
610 }
611
612 static void
613 nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
614 {
615         struct nfs4_client *clp = ls->ls_stid.sc_client;
616         char addr_str[INET6_ADDRSTRLEN];
617         static char *envp[] = {
618                 "HOME=/",
619                 "TERM=linux",
620                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
621                 NULL
622         };
623         char *argv[8];
624         int error;
625
626         rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));
627
628         printk(KERN_WARNING
629                 "nfsd: client %s failed to respond to layout recall. "
630                 "  Fencing..\n", addr_str);
631
632         argv[0] = "/sbin/nfsd-recall-failed";
633         argv[1] = addr_str;
634         argv[2] = ls->ls_file->f_path.mnt->mnt_sb->s_id;
635         argv[3] = NULL;
636
637         error = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
638         if (error) {
639                 printk(KERN_ERR "nfsd: fence failed for client %s: %d!\n",
640                         addr_str, error);
641         }
642 }
643
644 static void
645 nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)
646 {
647         struct nfs4_layout_stateid *ls =
648                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
649
650         mutex_lock(&ls->ls_mutex);
651         nfs4_inc_and_copy_stateid(&ls->ls_recall_sid, &ls->ls_stid);
652         mutex_unlock(&ls->ls_mutex);
653 }
654
655 static int
656 nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
657 {
658         struct nfs4_layout_stateid *ls =
659                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
660         struct nfsd_net *nn;
661         ktime_t now, cutoff;
662         const struct nfsd4_layout_ops *ops;
663         LIST_HEAD(reaplist);
664
665
666         switch (task->tk_status) {
667         case 0:
668         case -NFS4ERR_DELAY:
669                 /*
670                  * Anything left? If not, then call it done. Note that we don't
671                  * take the spinlock since this is an optimization and nothing
672                  * should get added until the cb counter goes to zero.
673                  */
674                 if (list_empty(&ls->ls_layouts))
675                         return 1;
676
677                 /* Poll the client until it's done with the layout */
678                 now = ktime_get();
679                 nn = net_generic(ls->ls_stid.sc_client->net, nfsd_net_id);
680
681                 /* Client gets 2 lease periods to return it */
682                 cutoff = ktime_add_ns(task->tk_start,
683                                          (u64)nn->nfsd4_lease * NSEC_PER_SEC * 2);
684
685                 if (ktime_before(now, cutoff)) {
686                         rpc_delay(task, HZ/100); /* 10 mili-seconds */
687                         return 0;
688                 }
689                 /* Fallthrough */
690         case -NFS4ERR_NOMATCHING_LAYOUT:
691                 trace_layout_recall_done(&ls->ls_stid.sc_stateid);
692                 task->tk_status = 0;
693                 return 1;
694         default:
695                 /*
696                  * Unknown error or non-responding client, we'll need to fence.
697                  */
698                 trace_layout_recall_fail(&ls->ls_stid.sc_stateid);
699
700                 ops = nfsd4_layout_ops[ls->ls_layout_type];
701                 if (ops->fence_client)
702                         ops->fence_client(ls);
703                 else
704                         nfsd4_cb_layout_fail(ls);
705                 return -1;
706         }
707 }
708
709 static void
710 nfsd4_cb_layout_release(struct nfsd4_callback *cb)
711 {
712         struct nfs4_layout_stateid *ls =
713                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
714         LIST_HEAD(reaplist);
715
716         trace_layout_recall_release(&ls->ls_stid.sc_stateid);
717
718         nfsd4_return_all_layouts(ls, &reaplist);
719         nfsd4_free_layouts(&reaplist);
720         nfs4_put_stid(&ls->ls_stid);
721 }
722
723 static const struct nfsd4_callback_ops nfsd4_cb_layout_ops = {
724         .prepare        = nfsd4_cb_layout_prepare,
725         .done           = nfsd4_cb_layout_done,
726         .release        = nfsd4_cb_layout_release,
727 };
728
729 static bool
730 nfsd4_layout_lm_break(struct file_lock *fl)
731 {
732         /*
733          * We don't want the locks code to timeout the lease for us;
734          * we'll remove it ourself if a layout isn't returned
735          * in time:
736          */
737         fl->fl_break_time = 0;
738         nfsd4_recall_file_layout(fl->fl_owner);
739         return false;
740 }
741
742 static int
743 nfsd4_layout_lm_change(struct file_lock *onlist, int arg,
744                 struct list_head *dispose)
745 {
746         BUG_ON(!(arg & F_UNLCK));
747         return lease_modify(onlist, arg, dispose);
748 }
749
750 static const struct lock_manager_operations nfsd4_layouts_lm_ops = {
751         .lm_break       = nfsd4_layout_lm_break,
752         .lm_change      = nfsd4_layout_lm_change,
753 };
754
755 int
756 nfsd4_init_pnfs(void)
757 {
758         int i;
759
760         for (i = 0; i < DEVID_HASH_SIZE; i++)
761                 INIT_LIST_HEAD(&nfsd_devid_hash[i]);
762
763         nfs4_layout_cache = kmem_cache_create("nfs4_layout",
764                         sizeof(struct nfs4_layout), 0, 0, NULL);
765         if (!nfs4_layout_cache)
766                 return -ENOMEM;
767
768         nfs4_layout_stateid_cache = kmem_cache_create("nfs4_layout_stateid",
769                         sizeof(struct nfs4_layout_stateid), 0, 0, NULL);
770         if (!nfs4_layout_stateid_cache) {
771                 kmem_cache_destroy(nfs4_layout_cache);
772                 return -ENOMEM;
773         }
774         return 0;
775 }
776
777 void
778 nfsd4_exit_pnfs(void)
779 {
780         int i;
781
782         kmem_cache_destroy(nfs4_layout_cache);
783         kmem_cache_destroy(nfs4_layout_stateid_cache);
784
785         for (i = 0; i < DEVID_HASH_SIZE; i++) {
786                 struct nfsd4_deviceid_map *map, *n;
787
788                 list_for_each_entry_safe(map, n, &nfsd_devid_hash[i], hash)
789                         kfree(map);
790         }
791 }