xref: /openbmc/linux/fs/nfsd/nfs4layouts.c (revision 4f6cce39)
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 const nfsd_recall_failed[] = "/sbin/nfsd-recall-failed";
618 	static char *envp[] = {
619 		"HOME=/",
620 		"TERM=linux",
621 		"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
622 		NULL
623 	};
624 	char *argv[8];
625 	int error;
626 
627 	rpc_ntop((struct sockaddr *)&clp->cl_addr, addr_str, sizeof(addr_str));
628 
629 	printk(KERN_WARNING
630 		"nfsd: client %s failed to respond to layout recall. "
631 		"  Fencing..\n", addr_str);
632 
633 	argv[0] = (char *)nfsd_recall_failed;
634 	argv[1] = addr_str;
635 	argv[2] = ls->ls_file->f_path.mnt->mnt_sb->s_id;
636 	argv[3] = NULL;
637 
638 	error = call_usermodehelper(nfsd_recall_failed, argv, envp,
639 				    UMH_WAIT_PROC);
640 	if (error) {
641 		printk(KERN_ERR "nfsd: fence failed for client %s: %d!\n",
642 			addr_str, error);
643 	}
644 }
645 
646 static void
647 nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)
648 {
649 	struct nfs4_layout_stateid *ls =
650 		container_of(cb, struct nfs4_layout_stateid, ls_recall);
651 
652 	mutex_lock(&ls->ls_mutex);
653 	nfs4_inc_and_copy_stateid(&ls->ls_recall_sid, &ls->ls_stid);
654 	mutex_unlock(&ls->ls_mutex);
655 }
656 
657 static int
658 nfsd4_cb_layout_done(struct nfsd4_callback *cb, struct rpc_task *task)
659 {
660 	struct nfs4_layout_stateid *ls =
661 		container_of(cb, struct nfs4_layout_stateid, ls_recall);
662 	struct nfsd_net *nn;
663 	ktime_t now, cutoff;
664 	const struct nfsd4_layout_ops *ops;
665 	LIST_HEAD(reaplist);
666 
667 
668 	switch (task->tk_status) {
669 	case 0:
670 	case -NFS4ERR_DELAY:
671 		/*
672 		 * Anything left? If not, then call it done. Note that we don't
673 		 * take the spinlock since this is an optimization and nothing
674 		 * should get added until the cb counter goes to zero.
675 		 */
676 		if (list_empty(&ls->ls_layouts))
677 			return 1;
678 
679 		/* Poll the client until it's done with the layout */
680 		now = ktime_get();
681 		nn = net_generic(ls->ls_stid.sc_client->net, nfsd_net_id);
682 
683 		/* Client gets 2 lease periods to return it */
684 		cutoff = ktime_add_ns(task->tk_start,
685 					 nn->nfsd4_lease * NSEC_PER_SEC * 2);
686 
687 		if (ktime_before(now, cutoff)) {
688 			rpc_delay(task, HZ/100); /* 10 mili-seconds */
689 			return 0;
690 		}
691 		/* Fallthrough */
692 	default:
693 		/*
694 		 * Unknown error or non-responding client, we'll need to fence.
695 		 */
696 		trace_layout_recall_fail(&ls->ls_stid.sc_stateid);
697 
698 		ops = nfsd4_layout_ops[ls->ls_layout_type];
699 		if (ops->fence_client)
700 			ops->fence_client(ls);
701 		else
702 			nfsd4_cb_layout_fail(ls);
703 		return -1;
704 	case -NFS4ERR_NOMATCHING_LAYOUT:
705 		trace_layout_recall_done(&ls->ls_stid.sc_stateid);
706 		task->tk_status = 0;
707 		return 1;
708 	}
709 }
710 
711 static void
712 nfsd4_cb_layout_release(struct nfsd4_callback *cb)
713 {
714 	struct nfs4_layout_stateid *ls =
715 		container_of(cb, struct nfs4_layout_stateid, ls_recall);
716 	LIST_HEAD(reaplist);
717 
718 	trace_layout_recall_release(&ls->ls_stid.sc_stateid);
719 
720 	nfsd4_return_all_layouts(ls, &reaplist);
721 	nfsd4_free_layouts(&reaplist);
722 	nfs4_put_stid(&ls->ls_stid);
723 }
724 
725 static const struct nfsd4_callback_ops nfsd4_cb_layout_ops = {
726 	.prepare	= nfsd4_cb_layout_prepare,
727 	.done		= nfsd4_cb_layout_done,
728 	.release	= nfsd4_cb_layout_release,
729 };
730 
731 static bool
732 nfsd4_layout_lm_break(struct file_lock *fl)
733 {
734 	/*
735 	 * We don't want the locks code to timeout the lease for us;
736 	 * we'll remove it ourself if a layout isn't returned
737 	 * in time:
738 	 */
739 	fl->fl_break_time = 0;
740 	nfsd4_recall_file_layout(fl->fl_owner);
741 	return false;
742 }
743 
744 static int
745 nfsd4_layout_lm_change(struct file_lock *onlist, int arg,
746 		struct list_head *dispose)
747 {
748 	BUG_ON(!(arg & F_UNLCK));
749 	return lease_modify(onlist, arg, dispose);
750 }
751 
752 static const struct lock_manager_operations nfsd4_layouts_lm_ops = {
753 	.lm_break	= nfsd4_layout_lm_break,
754 	.lm_change	= nfsd4_layout_lm_change,
755 };
756 
757 int
758 nfsd4_init_pnfs(void)
759 {
760 	int i;
761 
762 	for (i = 0; i < DEVID_HASH_SIZE; i++)
763 		INIT_LIST_HEAD(&nfsd_devid_hash[i]);
764 
765 	nfs4_layout_cache = kmem_cache_create("nfs4_layout",
766 			sizeof(struct nfs4_layout), 0, 0, NULL);
767 	if (!nfs4_layout_cache)
768 		return -ENOMEM;
769 
770 	nfs4_layout_stateid_cache = kmem_cache_create("nfs4_layout_stateid",
771 			sizeof(struct nfs4_layout_stateid), 0, 0, NULL);
772 	if (!nfs4_layout_stateid_cache) {
773 		kmem_cache_destroy(nfs4_layout_cache);
774 		return -ENOMEM;
775 	}
776 	return 0;
777 }
778 
779 void
780 nfsd4_exit_pnfs(void)
781 {
782 	int i;
783 
784 	kmem_cache_destroy(nfs4_layout_cache);
785 	kmem_cache_destroy(nfs4_layout_stateid_cache);
786 
787 	for (i = 0; i < DEVID_HASH_SIZE; i++) {
788 		struct nfsd4_deviceid_map *map, *n;
789 
790 		list_for_each_entry_safe(map, n, &nfsd_devid_hash[i], hash)
791 			kfree(map);
792 	}
793 }
794