Linux-libre 5.4.48-gnu
[librecmc/linux-libre.git] / fs / nfsd / nfs4layouts.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014 Christoph Hellwig.
4  */
5 #include <linux/blkdev.h>
6 #include <linux/kmod.h>
7 #include <linux/file.h>
8 #include <linux/jhash.h>
9 #include <linux/sched.h>
10 #include <linux/sunrpc/addr.h>
11
12 #include "pnfs.h"
13 #include "netns.h"
14 #include "trace.h"
15
16 #define NFSDDBG_FACILITY                NFSDDBG_PNFS
17
18 struct nfs4_layout {
19         struct list_head                lo_perstate;
20         struct nfs4_layout_stateid      *lo_state;
21         struct nfsd4_layout_seg         lo_seg;
22 };
23
24 static struct kmem_cache *nfs4_layout_cache;
25 static struct kmem_cache *nfs4_layout_stateid_cache;
26
27 static const struct nfsd4_callback_ops nfsd4_cb_layout_ops;
28 static const struct lock_manager_operations nfsd4_layouts_lm_ops;
29
30 const struct nfsd4_layout_ops *nfsd4_layout_ops[LAYOUT_TYPE_MAX] =  {
31 #ifdef CONFIG_NFSD_FLEXFILELAYOUT
32         [LAYOUT_FLEX_FILES]     = &ff_layout_ops,
33 #endif
34 #ifdef CONFIG_NFSD_BLOCKLAYOUT
35         [LAYOUT_BLOCK_VOLUME]   = &bl_layout_ops,
36 #endif
37 #ifdef CONFIG_NFSD_SCSILAYOUT
38         [LAYOUT_SCSI]           = &scsi_layout_ops,
39 #endif
40 };
41
42 /* pNFS device ID to export fsid mapping */
43 #define DEVID_HASH_BITS 8
44 #define DEVID_HASH_SIZE (1 << DEVID_HASH_BITS)
45 #define DEVID_HASH_MASK (DEVID_HASH_SIZE - 1)
46 static u64 nfsd_devid_seq = 1;
47 static struct list_head nfsd_devid_hash[DEVID_HASH_SIZE];
48 static DEFINE_SPINLOCK(nfsd_devid_lock);
49
50 static inline u32 devid_hashfn(u64 idx)
51 {
52         return jhash_2words(idx, idx >> 32, 0) & DEVID_HASH_MASK;
53 }
54
55 static void
56 nfsd4_alloc_devid_map(const struct svc_fh *fhp)
57 {
58         const struct knfsd_fh *fh = &fhp->fh_handle;
59         size_t fsid_len = key_len(fh->fh_fsid_type);
60         struct nfsd4_deviceid_map *map, *old;
61         int i;
62
63         map = kzalloc(sizeof(*map) + fsid_len, GFP_KERNEL);
64         if (!map)
65                 return;
66
67         map->fsid_type = fh->fh_fsid_type;
68         memcpy(&map->fsid, fh->fh_fsid, fsid_len);
69
70         spin_lock(&nfsd_devid_lock);
71         if (fhp->fh_export->ex_devid_map)
72                 goto out_unlock;
73
74         for (i = 0; i < DEVID_HASH_SIZE; i++) {
75                 list_for_each_entry(old, &nfsd_devid_hash[i], hash) {
76                         if (old->fsid_type != fh->fh_fsid_type)
77                                 continue;
78                         if (memcmp(old->fsid, fh->fh_fsid,
79                                         key_len(old->fsid_type)))
80                                 continue;
81
82                         fhp->fh_export->ex_devid_map = old;
83                         goto out_unlock;
84                 }
85         }
86
87         map->idx = nfsd_devid_seq++;
88         list_add_tail_rcu(&map->hash, &nfsd_devid_hash[devid_hashfn(map->idx)]);
89         fhp->fh_export->ex_devid_map = map;
90         map = NULL;
91
92 out_unlock:
93         spin_unlock(&nfsd_devid_lock);
94         kfree(map);
95 }
96
97 struct nfsd4_deviceid_map *
98 nfsd4_find_devid_map(int idx)
99 {
100         struct nfsd4_deviceid_map *map, *ret = NULL;
101
102         rcu_read_lock();
103         list_for_each_entry_rcu(map, &nfsd_devid_hash[devid_hashfn(idx)], hash)
104                 if (map->idx == idx)
105                         ret = map;
106         rcu_read_unlock();
107
108         return ret;
109 }
110
111 int
112 nfsd4_set_deviceid(struct nfsd4_deviceid *id, const struct svc_fh *fhp,
113                 u32 device_generation)
114 {
115         if (!fhp->fh_export->ex_devid_map) {
116                 nfsd4_alloc_devid_map(fhp);
117                 if (!fhp->fh_export->ex_devid_map)
118                         return -ENOMEM;
119         }
120
121         id->fsid_idx = fhp->fh_export->ex_devid_map->idx;
122         id->generation = device_generation;
123         id->pad = 0;
124         return 0;
125 }
126
127 void nfsd4_setup_layout_type(struct svc_export *exp)
128 {
129 #if defined(CONFIG_NFSD_BLOCKLAYOUT) || defined(CONFIG_NFSD_SCSILAYOUT)
130         struct super_block *sb = exp->ex_path.mnt->mnt_sb;
131 #endif
132
133         if (!(exp->ex_flags & NFSEXP_PNFS))
134                 return;
135
136 #ifdef CONFIG_NFSD_FLEXFILELAYOUT
137         exp->ex_layout_types |= 1 << LAYOUT_FLEX_FILES;
138 #endif
139 #ifdef CONFIG_NFSD_BLOCKLAYOUT
140         if (sb->s_export_op->get_uuid &&
141             sb->s_export_op->map_blocks &&
142             sb->s_export_op->commit_blocks)
143                 exp->ex_layout_types |= 1 << LAYOUT_BLOCK_VOLUME;
144 #endif
145 #ifdef CONFIG_NFSD_SCSILAYOUT
146         if (sb->s_export_op->map_blocks &&
147             sb->s_export_op->commit_blocks &&
148             sb->s_bdev && sb->s_bdev->bd_disk->fops->pr_ops &&
149                 blk_queue_scsi_passthrough(sb->s_bdev->bd_disk->queue))
150                 exp->ex_layout_types |= 1 << LAYOUT_SCSI;
151 #endif
152 }
153
154 static void
155 nfsd4_free_layout_stateid(struct nfs4_stid *stid)
156 {
157         struct nfs4_layout_stateid *ls = layoutstateid(stid);
158         struct nfs4_client *clp = ls->ls_stid.sc_client;
159         struct nfs4_file *fp = ls->ls_stid.sc_file;
160
161         trace_nfsd_layoutstate_free(&ls->ls_stid.sc_stateid);
162
163         spin_lock(&clp->cl_lock);
164         list_del_init(&ls->ls_perclnt);
165         spin_unlock(&clp->cl_lock);
166
167         spin_lock(&fp->fi_lock);
168         list_del_init(&ls->ls_perfile);
169         spin_unlock(&fp->fi_lock);
170
171         if (!nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
172                 vfs_setlease(ls->ls_file->nf_file, F_UNLCK, NULL, (void **)&ls);
173         nfsd_file_put(ls->ls_file);
174
175         if (ls->ls_recalled)
176                 atomic_dec(&ls->ls_stid.sc_file->fi_lo_recalls);
177
178         kmem_cache_free(nfs4_layout_stateid_cache, ls);
179 }
180
181 static int
182 nfsd4_layout_setlease(struct nfs4_layout_stateid *ls)
183 {
184         struct file_lock *fl;
185         int status;
186
187         if (nfsd4_layout_ops[ls->ls_layout_type]->disable_recalls)
188                 return 0;
189
190         fl = locks_alloc_lock();
191         if (!fl)
192                 return -ENOMEM;
193         locks_init_lock(fl);
194         fl->fl_lmops = &nfsd4_layouts_lm_ops;
195         fl->fl_flags = FL_LAYOUT;
196         fl->fl_type = F_RDLCK;
197         fl->fl_end = OFFSET_MAX;
198         fl->fl_owner = ls;
199         fl->fl_pid = current->tgid;
200         fl->fl_file = ls->ls_file->nf_file;
201
202         status = vfs_setlease(fl->fl_file, fl->fl_type, &fl, NULL);
203         if (status) {
204                 locks_free_lock(fl);
205                 return status;
206         }
207         BUG_ON(fl != NULL);
208         return 0;
209 }
210
211 static struct nfs4_layout_stateid *
212 nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
213                 struct nfs4_stid *parent, u32 layout_type)
214 {
215         struct nfs4_client *clp = cstate->clp;
216         struct nfs4_file *fp = parent->sc_file;
217         struct nfs4_layout_stateid *ls;
218         struct nfs4_stid *stp;
219
220         stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache,
221                                         nfsd4_free_layout_stateid);
222         if (!stp)
223                 return NULL;
224
225         get_nfs4_file(fp);
226         stp->sc_file = fp;
227
228         ls = layoutstateid(stp);
229         INIT_LIST_HEAD(&ls->ls_perclnt);
230         INIT_LIST_HEAD(&ls->ls_perfile);
231         spin_lock_init(&ls->ls_lock);
232         INIT_LIST_HEAD(&ls->ls_layouts);
233         mutex_init(&ls->ls_mutex);
234         ls->ls_layout_type = layout_type;
235         nfsd4_init_cb(&ls->ls_recall, clp, &nfsd4_cb_layout_ops,
236                         NFSPROC4_CLNT_CB_LAYOUT);
237
238         if (parent->sc_type == NFS4_DELEG_STID)
239                 ls->ls_file = nfsd_file_get(fp->fi_deleg_file);
240         else
241                 ls->ls_file = find_any_file(fp);
242         BUG_ON(!ls->ls_file);
243
244         if (nfsd4_layout_setlease(ls)) {
245                 nfsd_file_put(ls->ls_file);
246                 put_nfs4_file(fp);
247                 kmem_cache_free(nfs4_layout_stateid_cache, ls);
248                 return NULL;
249         }
250
251         spin_lock(&clp->cl_lock);
252         stp->sc_type = NFS4_LAYOUT_STID;
253         list_add(&ls->ls_perclnt, &clp->cl_lo_states);
254         spin_unlock(&clp->cl_lock);
255
256         spin_lock(&fp->fi_lock);
257         list_add(&ls->ls_perfile, &fp->fi_lo_states);
258         spin_unlock(&fp->fi_lock);
259
260         trace_nfsd_layoutstate_alloc(&ls->ls_stid.sc_stateid);
261         return ls;
262 }
263
264 __be32
265 nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
266                 struct nfsd4_compound_state *cstate, stateid_t *stateid,
267                 bool create, u32 layout_type, struct nfs4_layout_stateid **lsp)
268 {
269         struct nfs4_layout_stateid *ls;
270         struct nfs4_stid *stid;
271         unsigned char typemask = NFS4_LAYOUT_STID;
272         __be32 status;
273
274         if (create)
275                 typemask |= (NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID);
276
277         status = nfsd4_lookup_stateid(cstate, stateid, typemask, &stid,
278                         net_generic(SVC_NET(rqstp), nfsd_net_id));
279         if (status)
280                 goto out;
281
282         if (!fh_match(&cstate->current_fh.fh_handle,
283                       &stid->sc_file->fi_fhandle)) {
284                 status = nfserr_bad_stateid;
285                 goto out_put_stid;
286         }
287
288         if (stid->sc_type != NFS4_LAYOUT_STID) {
289                 ls = nfsd4_alloc_layout_stateid(cstate, stid, layout_type);
290                 nfs4_put_stid(stid);
291
292                 status = nfserr_jukebox;
293                 if (!ls)
294                         goto out;
295                 mutex_lock(&ls->ls_mutex);
296         } else {
297                 ls = container_of(stid, struct nfs4_layout_stateid, ls_stid);
298
299                 status = nfserr_bad_stateid;
300                 mutex_lock(&ls->ls_mutex);
301                 if (nfsd4_stateid_generation_after(stateid, &stid->sc_stateid))
302                         goto out_unlock_stid;
303                 if (layout_type != ls->ls_layout_type)
304                         goto out_unlock_stid;
305         }
306
307         *lsp = ls;
308         return 0;
309
310 out_unlock_stid:
311         mutex_unlock(&ls->ls_mutex);
312 out_put_stid:
313         nfs4_put_stid(stid);
314 out:
315         return status;
316 }
317
318 static void
319 nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
320 {
321         spin_lock(&ls->ls_lock);
322         if (ls->ls_recalled)
323                 goto out_unlock;
324
325         ls->ls_recalled = true;
326         atomic_inc(&ls->ls_stid.sc_file->fi_lo_recalls);
327         if (list_empty(&ls->ls_layouts))
328                 goto out_unlock;
329
330         trace_nfsd_layout_recall(&ls->ls_stid.sc_stateid);
331
332         refcount_inc(&ls->ls_stid.sc_count);
333         nfsd4_run_cb(&ls->ls_recall);
334
335 out_unlock:
336         spin_unlock(&ls->ls_lock);
337 }
338
339 static inline u64
340 layout_end(struct nfsd4_layout_seg *seg)
341 {
342         u64 end = seg->offset + seg->length;
343         return end >= seg->offset ? end : NFS4_MAX_UINT64;
344 }
345
346 static void
347 layout_update_len(struct nfsd4_layout_seg *lo, u64 end)
348 {
349         if (end == NFS4_MAX_UINT64)
350                 lo->length = NFS4_MAX_UINT64;
351         else
352                 lo->length = end - lo->offset;
353 }
354
355 static bool
356 layouts_overlapping(struct nfs4_layout *lo, struct nfsd4_layout_seg *s)
357 {
358         if (s->iomode != IOMODE_ANY && s->iomode != lo->lo_seg.iomode)
359                 return false;
360         if (layout_end(&lo->lo_seg) <= s->offset)
361                 return false;
362         if (layout_end(s) <= lo->lo_seg.offset)
363                 return false;
364         return true;
365 }
366
367 static bool
368 layouts_try_merge(struct nfsd4_layout_seg *lo, struct nfsd4_layout_seg *new)
369 {
370         if (lo->iomode != new->iomode)
371                 return false;
372         if (layout_end(new) < lo->offset)
373                 return false;
374         if (layout_end(lo) < new->offset)
375                 return false;
376
377         lo->offset = min(lo->offset, new->offset);
378         layout_update_len(lo, max(layout_end(lo), layout_end(new)));
379         return true;
380 }
381
382 static __be32
383 nfsd4_recall_conflict(struct nfs4_layout_stateid *ls)
384 {
385         struct nfs4_file *fp = ls->ls_stid.sc_file;
386         struct nfs4_layout_stateid *l, *n;
387         __be32 nfserr = nfs_ok;
388
389         assert_spin_locked(&fp->fi_lock);
390
391         list_for_each_entry_safe(l, n, &fp->fi_lo_states, ls_perfile) {
392                 if (l != ls) {
393                         nfsd4_recall_file_layout(l);
394                         nfserr = nfserr_recallconflict;
395                 }
396         }
397
398         return nfserr;
399 }
400
401 __be32
402 nfsd4_insert_layout(struct nfsd4_layoutget *lgp, struct nfs4_layout_stateid *ls)
403 {
404         struct nfsd4_layout_seg *seg = &lgp->lg_seg;
405         struct nfs4_file *fp = ls->ls_stid.sc_file;
406         struct nfs4_layout *lp, *new = NULL;
407         __be32 nfserr;
408
409         spin_lock(&fp->fi_lock);
410         nfserr = nfsd4_recall_conflict(ls);
411         if (nfserr)
412                 goto out;
413         spin_lock(&ls->ls_lock);
414         list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
415                 if (layouts_try_merge(&lp->lo_seg, seg))
416                         goto done;
417         }
418         spin_unlock(&ls->ls_lock);
419         spin_unlock(&fp->fi_lock);
420
421         new = kmem_cache_alloc(nfs4_layout_cache, GFP_KERNEL);
422         if (!new)
423                 return nfserr_jukebox;
424         memcpy(&new->lo_seg, seg, sizeof(lp->lo_seg));
425         new->lo_state = ls;
426
427         spin_lock(&fp->fi_lock);
428         nfserr = nfsd4_recall_conflict(ls);
429         if (nfserr)
430                 goto out;
431         spin_lock(&ls->ls_lock);
432         list_for_each_entry(lp, &ls->ls_layouts, lo_perstate) {
433                 if (layouts_try_merge(&lp->lo_seg, seg))
434                         goto done;
435         }
436
437         refcount_inc(&ls->ls_stid.sc_count);
438         list_add_tail(&new->lo_perstate, &ls->ls_layouts);
439         new = NULL;
440 done:
441         nfs4_inc_and_copy_stateid(&lgp->lg_sid, &ls->ls_stid);
442         spin_unlock(&ls->ls_lock);
443 out:
444         spin_unlock(&fp->fi_lock);
445         if (new)
446                 kmem_cache_free(nfs4_layout_cache, new);
447         return nfserr;
448 }
449
450 static void
451 nfsd4_free_layouts(struct list_head *reaplist)
452 {
453         while (!list_empty(reaplist)) {
454                 struct nfs4_layout *lp = list_first_entry(reaplist,
455                                 struct nfs4_layout, lo_perstate);
456
457                 list_del(&lp->lo_perstate);
458                 nfs4_put_stid(&lp->lo_state->ls_stid);
459                 kmem_cache_free(nfs4_layout_cache, lp);
460         }
461 }
462
463 static void
464 nfsd4_return_file_layout(struct nfs4_layout *lp, struct nfsd4_layout_seg *seg,
465                 struct list_head *reaplist)
466 {
467         struct nfsd4_layout_seg *lo = &lp->lo_seg;
468         u64 end = layout_end(lo);
469
470         if (seg->offset <= lo->offset) {
471                 if (layout_end(seg) >= end) {
472                         list_move_tail(&lp->lo_perstate, reaplist);
473                         return;
474                 }
475                 lo->offset = layout_end(seg);
476         } else {
477                 /* retain the whole layout segment on a split. */
478                 if (layout_end(seg) < end) {
479                         dprintk("%s: split not supported\n", __func__);
480                         return;
481                 }
482                 end = seg->offset;
483         }
484
485         layout_update_len(lo, end);
486 }
487
488 __be32
489 nfsd4_return_file_layouts(struct svc_rqst *rqstp,
490                 struct nfsd4_compound_state *cstate,
491                 struct nfsd4_layoutreturn *lrp)
492 {
493         struct nfs4_layout_stateid *ls;
494         struct nfs4_layout *lp, *n;
495         LIST_HEAD(reaplist);
496         __be32 nfserr;
497         int found = 0;
498
499         nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lrp->lr_sid,
500                                                 false, lrp->lr_layout_type,
501                                                 &ls);
502         if (nfserr) {
503                 trace_nfsd_layout_return_lookup_fail(&lrp->lr_sid);
504                 return nfserr;
505         }
506
507         spin_lock(&ls->ls_lock);
508         list_for_each_entry_safe(lp, n, &ls->ls_layouts, lo_perstate) {
509                 if (layouts_overlapping(lp, &lrp->lr_seg)) {
510                         nfsd4_return_file_layout(lp, &lrp->lr_seg, &reaplist);
511                         found++;
512                 }
513         }
514         if (!list_empty(&ls->ls_layouts)) {
515                 if (found)
516                         nfs4_inc_and_copy_stateid(&lrp->lr_sid, &ls->ls_stid);
517                 lrp->lrs_present = 1;
518         } else {
519                 trace_nfsd_layoutstate_unhash(&ls->ls_stid.sc_stateid);
520                 nfs4_unhash_stid(&ls->ls_stid);
521                 lrp->lrs_present = 0;
522         }
523         spin_unlock(&ls->ls_lock);
524
525         mutex_unlock(&ls->ls_mutex);
526         nfs4_put_stid(&ls->ls_stid);
527         nfsd4_free_layouts(&reaplist);
528         return nfs_ok;
529 }
530
531 __be32
532 nfsd4_return_client_layouts(struct svc_rqst *rqstp,
533                 struct nfsd4_compound_state *cstate,
534                 struct nfsd4_layoutreturn *lrp)
535 {
536         struct nfs4_layout_stateid *ls, *n;
537         struct nfs4_client *clp = cstate->clp;
538         struct nfs4_layout *lp, *t;
539         LIST_HEAD(reaplist);
540
541         lrp->lrs_present = 0;
542
543         spin_lock(&clp->cl_lock);
544         list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt) {
545                 if (ls->ls_layout_type != lrp->lr_layout_type)
546                         continue;
547
548                 if (lrp->lr_return_type == RETURN_FSID &&
549                     !fh_fsid_match(&ls->ls_stid.sc_file->fi_fhandle,
550                                    &cstate->current_fh.fh_handle))
551                         continue;
552
553                 spin_lock(&ls->ls_lock);
554                 list_for_each_entry_safe(lp, t, &ls->ls_layouts, lo_perstate) {
555                         if (lrp->lr_seg.iomode == IOMODE_ANY ||
556                             lrp->lr_seg.iomode == lp->lo_seg.iomode)
557                                 list_move_tail(&lp->lo_perstate, &reaplist);
558                 }
559                 spin_unlock(&ls->ls_lock);
560         }
561         spin_unlock(&clp->cl_lock);
562
563         nfsd4_free_layouts(&reaplist);
564         return 0;
565 }
566
567 static void
568 nfsd4_return_all_layouts(struct nfs4_layout_stateid *ls,
569                 struct list_head *reaplist)
570 {
571         spin_lock(&ls->ls_lock);
572         list_splice_init(&ls->ls_layouts, reaplist);
573         spin_unlock(&ls->ls_lock);
574 }
575
576 void
577 nfsd4_return_all_client_layouts(struct nfs4_client *clp)
578 {
579         struct nfs4_layout_stateid *ls, *n;
580         LIST_HEAD(reaplist);
581
582         spin_lock(&clp->cl_lock);
583         list_for_each_entry_safe(ls, n, &clp->cl_lo_states, ls_perclnt)
584                 nfsd4_return_all_layouts(ls, &reaplist);
585         spin_unlock(&clp->cl_lock);
586
587         nfsd4_free_layouts(&reaplist);
588 }
589
590 void
591 nfsd4_return_all_file_layouts(struct nfs4_client *clp, struct nfs4_file *fp)
592 {
593         struct nfs4_layout_stateid *ls, *n;
594         LIST_HEAD(reaplist);
595
596         spin_lock(&fp->fi_lock);
597         list_for_each_entry_safe(ls, n, &fp->fi_lo_states, ls_perfile) {
598                 if (ls->ls_stid.sc_client == clp)
599                         nfsd4_return_all_layouts(ls, &reaplist);
600         }
601         spin_unlock(&fp->fi_lock);
602
603         nfsd4_free_layouts(&reaplist);
604 }
605
606 static void
607 nfsd4_cb_layout_fail(struct nfs4_layout_stateid *ls)
608 {
609         struct nfs4_client *clp = ls->ls_stid.sc_client;
610         char addr_str[INET6_ADDRSTRLEN];
611         static char const nfsd_recall_failed[] = "/sbin/nfsd-recall-failed";
612         static char *envp[] = {
613                 "HOME=/",
614                 "TERM=linux",
615                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
616                 NULL
617         };
618         char *argv[8];
619         int error;
620
621         rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));
622
623         printk(KERN_WARNING
624                 "nfsd: client %s failed to respond to layout recall. "
625                 "  Fencing..\n", addr_str);
626
627         argv[0] = (char *)nfsd_recall_failed;
628         argv[1] = addr_str;
629         argv[2] = ls->ls_file->nf_file->f_path.mnt->mnt_sb->s_id;
630         argv[3] = NULL;
631
632         error = call_usermodehelper(nfsd_recall_failed, argv, envp,
633                                     UMH_WAIT_PROC);
634         if (error) {
635                 printk(KERN_ERR "nfsd: fence failed for client %s: %d!\n",
636                         addr_str, error);
637         }
638 }
639
640 static void
641 nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)
642 {
643         struct nfs4_layout_stateid *ls =
644                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
645
646         mutex_lock(&ls->ls_mutex);
647         nfs4_inc_and_copy_stateid(&ls->ls_recall_sid, &ls->ls_stid);
648         mutex_unlock(&ls->ls_mutex);
649 }
650
651 static int
652 nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
653 {
654         struct nfs4_layout_stateid *ls =
655                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
656         struct nfsd_net *nn;
657         ktime_t now, cutoff;
658         const struct nfsd4_layout_ops *ops;
659
660
661         switch (task->tk_status) {
662         case 0:
663         case -NFS4ERR_DELAY:
664                 /*
665                  * Anything left? If not, then call it done. Note that we don't
666                  * take the spinlock since this is an optimization and nothing
667                  * should get added until the cb counter goes to zero.
668                  */
669                 if (list_empty(&ls->ls_layouts))
670                         return 1;
671
672                 /* Poll the client until it's done with the layout */
673                 now = ktime_get();
674                 nn = net_generic(ls->ls_stid.sc_client->net, nfsd_net_id);
675
676                 /* Client gets 2 lease periods to return it */
677                 cutoff = ktime_add_ns(task->tk_start,
678                                          (u64)nn->nfsd4_lease * NSEC_PER_SEC * 2);
679
680                 if (ktime_before(now, cutoff)) {
681                         rpc_delay(task, HZ/100); /* 10 mili-seconds */
682                         return 0;
683                 }
684                 /* Fallthrough */
685         default:
686                 /*
687                  * Unknown error or non-responding client, we'll need to fence.
688                  */
689                 trace_nfsd_layout_recall_fail(&ls->ls_stid.sc_stateid);
690
691                 ops = nfsd4_layout_ops[ls->ls_layout_type];
692                 if (ops->fence_client)
693                         ops->fence_client(ls);
694                 else
695                         nfsd4_cb_layout_fail(ls);
696                 return 1;
697         case -NFS4ERR_NOMATCHING_LAYOUT:
698                 trace_nfsd_layout_recall_done(&ls->ls_stid.sc_stateid);
699                 task->tk_status = 0;
700                 return 1;
701         }
702 }
703
704 static void
705 nfsd4_cb_layout_release(struct nfsd4_callback *cb)
706 {
707         struct nfs4_layout_stateid *ls =
708                 container_of(cb, struct nfs4_layout_stateid, ls_recall);
709         LIST_HEAD(reaplist);
710
711         trace_nfsd_layout_recall_release(&ls->ls_stid.sc_stateid);
712
713         nfsd4_return_all_layouts(ls, &reaplist);
714         nfsd4_free_layouts(&reaplist);
715         nfs4_put_stid(&ls->ls_stid);
716 }
717
718 static const struct nfsd4_callback_ops nfsd4_cb_layout_ops = {
719         .prepare        = nfsd4_cb_layout_prepare,
720         .done           = nfsd4_cb_layout_done,
721         .release        = nfsd4_cb_layout_release,
722 };
723
724 static bool
725 nfsd4_layout_lm_break(struct file_lock *fl)
726 {
727         /*
728          * We don't want the locks code to timeout the lease for us;
729          * we'll remove it ourself if a layout isn't returned
730          * in time:
731          */
732         fl->fl_break_time = 0;
733         nfsd4_recall_file_layout(fl->fl_owner);
734         return false;
735 }
736
737 static int
738 nfsd4_layout_lm_change(struct file_lock *onlist, int arg,
739                 struct list_head *dispose)
740 {
741         BUG_ON(!(arg & F_UNLCK));
742         return lease_modify(onlist, arg, dispose);
743 }
744
745 static const struct lock_manager_operations nfsd4_layouts_lm_ops = {
746         .lm_break       = nfsd4_layout_lm_break,
747         .lm_change      = nfsd4_layout_lm_change,
748 };
749
750 int
751 nfsd4_init_pnfs(void)
752 {
753         int i;
754
755         for (i = 0; i < DEVID_HASH_SIZE; i++)
756                 INIT_LIST_HEAD(&nfsd_devid_hash[i]);
757
758         nfs4_layout_cache = kmem_cache_create("nfs4_layout",
759                         sizeof(struct nfs4_layout), 0, 0, NULL);
760         if (!nfs4_layout_cache)
761                 return -ENOMEM;
762
763         nfs4_layout_stateid_cache = kmem_cache_create("nfs4_layout_stateid",
764                         sizeof(struct nfs4_layout_stateid), 0, 0, NULL);
765         if (!nfs4_layout_stateid_cache) {
766                 kmem_cache_destroy(nfs4_layout_cache);
767                 return -ENOMEM;
768         }
769         return 0;
770 }
771
772 void
773 nfsd4_exit_pnfs(void)
774 {
775         int i;
776
777         kmem_cache_destroy(nfs4_layout_cache);
778         kmem_cache_destroy(nfs4_layout_stateid_cache);
779
780         for (i = 0; i < DEVID_HASH_SIZE; i++) {
781                 struct nfsd4_deviceid_map *map, *n;
782
783                 list_for_each_entry_safe(map, n, &nfsd_devid_hash[i], hash)
784                         kfree(map);
785         }
786 }