xref: /openbmc/linux/fs/nfsd/nfs4layouts.c (revision 7587eb18)
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 (nfsd4_stateid_generation_after(stateid, &stid->sc_stateid))
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 }
777