xref: /linux/fs/nfs/callback_proc.c (revision 23b0f90ba871f096474e1c27c3d14f455189d2d9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/fs/nfs/callback_proc.c
4  *
5  * Copyright (C) 2004 Trond Myklebust
6  *
7  * NFSv4 callback procedures
8  */
9 
10 #include <linux/errno.h>
11 #include <linux/math.h>
12 #include <linux/nfs4.h>
13 #include <linux/nfs_fs.h>
14 #include <linux/slab.h>
15 #include <linux/rcupdate.h>
16 #include <linux/types.h>
17 
18 #include "nfs4_fs.h"
19 #include "callback.h"
20 #include "delegation.h"
21 #include "internal.h"
22 #include "pnfs.h"
23 #include "nfs4session.h"
24 #include "nfs4trace.h"
25 
26 #define NFSDBG_FACILITY NFSDBG_CALLBACK
27 
28 __be32 nfs4_callback_getattr(void *argp, void *resp,
29 			     struct cb_process_state *cps)
30 {
31 	struct cb_getattrargs *args = argp;
32 	struct cb_getattrres *res = resp;
33 	struct nfs_delegation *delegation;
34 	struct inode *inode;
35 
36 	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
37 	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
38 		goto out;
39 
40 	memset(res->bitmap, 0, sizeof(res->bitmap));
41 	res->status = htonl(NFS4ERR_BADHANDLE);
42 
43 	dprintk_rcu("NFS: GETATTR callback request from %s\n",
44 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
45 
46 	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
47 	if (IS_ERR(inode)) {
48 		if (inode == ERR_PTR(-EAGAIN))
49 			res->status = htonl(NFS4ERR_DELAY);
50 		trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
51 				-ntohl(res->status));
52 		goto out;
53 	}
54 
55 	delegation = nfs4_get_valid_delegation(inode);
56 	if (!delegation)
57 		goto out_iput;
58 	if ((delegation->type & FMODE_WRITE) == 0) {
59 		nfs_put_delegation(delegation);
60 		goto out_iput;
61 	}
62 	res->change_attr = delegation->change_attr;
63 	nfs_put_delegation(delegation);
64 
65 	res->size = i_size_read(inode);
66 	if (nfs_have_writebacks(inode))
67 		res->change_attr++;
68 	res->atime = inode_get_atime(inode);
69 	res->ctime = inode_get_ctime(inode);
70 	res->mtime = inode_get_mtime(inode);
71 	res->bitmap[0] = (FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE) &
72 			 args->bitmap[0];
73 	res->bitmap[1] = (FATTR4_WORD1_TIME_ACCESS |
74 			  FATTR4_WORD1_TIME_METADATA |
75 			  FATTR4_WORD1_TIME_MODIFY) & args->bitmap[1];
76 	res->bitmap[2] = (FATTR4_WORD2_TIME_DELEG_ACCESS |
77 			  FATTR4_WORD2_TIME_DELEG_MODIFY) & args->bitmap[2];
78 	res->status = 0;
79 out_iput:
80 	trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
81 	nfs_iput_and_deactive(inode);
82 out:
83 	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
84 	return res->status;
85 }
86 
87 __be32 nfs4_callback_recall(void *argp, void *resp,
88 			    struct cb_process_state *cps)
89 {
90 	struct cb_recallargs *args = argp;
91 	struct inode *inode;
92 	__be32 res;
93 
94 	res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
95 	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
96 		goto out;
97 
98 	dprintk_rcu("NFS: RECALL callback request from %s\n",
99 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
100 
101 	res = htonl(NFS4ERR_BADHANDLE);
102 	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
103 	if (IS_ERR(inode)) {
104 		if (inode == ERR_PTR(-EAGAIN))
105 			res = htonl(NFS4ERR_DELAY);
106 		trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
107 				&args->stateid, -ntohl(res));
108 		goto out;
109 	}
110 	/* Set up a helper thread to actually return the delegation */
111 	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
112 	case 0:
113 		res = 0;
114 		break;
115 	case -ENOENT:
116 		res = htonl(NFS4ERR_BAD_STATEID);
117 		break;
118 	default:
119 		res = htonl(NFS4ERR_RESOURCE);
120 	}
121 	trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
122 			&args->stateid, -ntohl(res));
123 	nfs_iput_and_deactive(inode);
124 out:
125 	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
126 	return res;
127 }
128 
129 /*
130  * Lookup a layout inode by stateid
131  *
132  * Note: returns a refcount on the inode and superblock
133  */
134 static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
135 		const nfs4_stateid *stateid)
136 	__must_hold(RCU)
137 {
138 	struct nfs_server *server;
139 	struct inode *inode;
140 	struct pnfs_layout_hdr *lo;
141 
142 	rcu_read_lock();
143 	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
144 		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
145 			if (!pnfs_layout_is_valid(lo))
146 				continue;
147 			if (!nfs4_stateid_match_other(stateid, &lo->plh_stateid))
148 				continue;
149 			if (nfs_sb_active(server->super))
150 				inode = igrab(lo->plh_inode);
151 			else
152 				inode = ERR_PTR(-EAGAIN);
153 			rcu_read_unlock();
154 			if (inode)
155 				return inode;
156 			nfs_sb_deactive(server->super);
157 			return ERR_PTR(-EAGAIN);
158 		}
159 	}
160 	rcu_read_unlock();
161 	return ERR_PTR(-ENOENT);
162 }
163 
164 /*
165  * Lookup a layout inode by filehandle.
166  *
167  * Note: returns a refcount on the inode and superblock
168  *
169  */
170 static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
171 		const struct nfs_fh *fh)
172 {
173 	struct nfs_server *server;
174 	struct nfs_inode *nfsi;
175 	struct inode *inode;
176 	struct pnfs_layout_hdr *lo;
177 
178 	rcu_read_lock();
179 	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
180 		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
181 			nfsi = NFS_I(lo->plh_inode);
182 			if (nfs_compare_fh(fh, &nfsi->fh))
183 				continue;
184 			if (nfsi->layout != lo)
185 				continue;
186 			if (nfs_sb_active(server->super))
187 				inode = igrab(lo->plh_inode);
188 			else
189 				inode = ERR_PTR(-EAGAIN);
190 			rcu_read_unlock();
191 			if (inode)
192 				return inode;
193 			nfs_sb_deactive(server->super);
194 			return ERR_PTR(-EAGAIN);
195 		}
196 	}
197 	rcu_read_unlock();
198 	return ERR_PTR(-ENOENT);
199 }
200 
201 static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
202 		const struct nfs_fh *fh,
203 		const nfs4_stateid *stateid)
204 {
205 	struct inode *inode;
206 
207 	inode = nfs_layout_find_inode_by_stateid(clp, stateid);
208 	if (inode == ERR_PTR(-ENOENT))
209 		inode = nfs_layout_find_inode_by_fh(clp, fh);
210 	return inode;
211 }
212 
213 /*
214  * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
215  */
216 static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
217 					const nfs4_stateid *new,
218 					struct cb_process_state *cps)
219 {
220 	u32 oldseq, newseq;
221 
222 	/* Is the stateid not initialised? */
223 	if (!pnfs_layout_is_valid(lo))
224 		return NFS4ERR_NOMATCHING_LAYOUT;
225 
226 	/* Mismatched stateid? */
227 	if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
228 		return NFS4ERR_BAD_STATEID;
229 
230 	newseq = be32_to_cpu(new->seqid);
231 	/* Are we already in a layout recall situation? */
232 	if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
233 		return NFS4ERR_DELAY;
234 
235 	/*
236 	 * Check that the stateid matches what we think it should be.
237 	 * Note that if the server sent us a list of referring calls,
238 	 * and we know that those have completed, then we trust the
239 	 * stateid argument is correct.
240 	 */
241 	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
242 	if (newseq > oldseq + 1 && !cps->referring_calls)
243 		return NFS4ERR_DELAY;
244 
245 	/* Crazy server! */
246 	if (newseq <= oldseq)
247 		return NFS4ERR_OLD_STATEID;
248 
249 	return NFS_OK;
250 }
251 
252 static u32 initiate_file_draining(struct nfs_client *clp,
253 				  struct cb_layoutrecallargs *args,
254 				  struct cb_process_state *cps)
255 {
256 	struct inode *ino;
257 	struct pnfs_layout_hdr *lo;
258 	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
259 	LIST_HEAD(free_me_list);
260 
261 	ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
262 	if (IS_ERR(ino)) {
263 		if (ino == ERR_PTR(-EAGAIN))
264 			rv = NFS4ERR_DELAY;
265 		goto out_noput;
266 	}
267 
268 	pnfs_layoutcommit_inode(ino, false);
269 
270 
271 	spin_lock(&ino->i_lock);
272 	lo = NFS_I(ino)->layout;
273 	if (!lo) {
274 		spin_unlock(&ino->i_lock);
275 		goto out;
276 	}
277 	pnfs_get_layout_hdr(lo);
278 	rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid, cps);
279 	if (rv != NFS_OK)
280 		goto unlock;
281 
282 	/*
283 	 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
284 	 */
285 	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
286 		rv = NFS4ERR_DELAY;
287 		goto unlock;
288 	}
289 
290 	pnfs_set_layout_stateid(lo, &args->cbl_stateid, NULL, true);
291 	switch (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
292 				&args->cbl_range,
293 				be32_to_cpu(args->cbl_stateid.seqid))) {
294 	case 0:
295 	case -EBUSY:
296 		/* There are layout segments that need to be returned */
297 		rv = NFS4_OK;
298 		break;
299 	case -ENOENT:
300 		set_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags);
301 		/* Embrace your forgetfulness! */
302 		rv = NFS4ERR_NOMATCHING_LAYOUT;
303 
304 		if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
305 			NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
306 				&args->cbl_range);
307 		}
308 	}
309 unlock:
310 	spin_unlock(&ino->i_lock);
311 	pnfs_free_lseg_list(&free_me_list);
312 	/* Free all lsegs that are attached to commit buckets */
313 	nfs_commit_inode(ino, 0);
314 	pnfs_put_layout_hdr(lo);
315 out:
316 	nfs_iput_and_deactive(ino);
317 out_noput:
318 	trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
319 			&args->cbl_stateid, -rv);
320 	return rv;
321 }
322 
323 static u32 initiate_bulk_draining(struct nfs_client *clp,
324 				  struct cb_layoutrecallargs *args)
325 {
326 	int stat;
327 
328 	if (args->cbl_recall_type == RETURN_FSID)
329 		stat = pnfs_layout_destroy_byfsid(clp, &args->cbl_fsid,
330 						  PNFS_LAYOUT_BULK_RETURN);
331 	else
332 		stat = pnfs_layout_destroy_byclid(clp, PNFS_LAYOUT_BULK_RETURN);
333 	if (stat != 0)
334 		return NFS4ERR_DELAY;
335 	return NFS4ERR_NOMATCHING_LAYOUT;
336 }
337 
338 static u32 do_callback_layoutrecall(struct nfs_client *clp,
339 				    struct cb_layoutrecallargs *args,
340 				    struct cb_process_state *cps)
341 {
342 	if (args->cbl_recall_type == RETURN_FILE)
343 		return initiate_file_draining(clp, args, cps);
344 	return initiate_bulk_draining(clp, args);
345 }
346 
347 __be32 nfs4_callback_layoutrecall(void *argp, void *resp,
348 				  struct cb_process_state *cps)
349 {
350 	struct cb_layoutrecallargs *args = argp;
351 	u32 res = NFS4ERR_OP_NOT_IN_SESSION;
352 
353 	if (cps->clp)
354 		res = do_callback_layoutrecall(cps->clp, args, cps);
355 	return cpu_to_be32(res);
356 }
357 
358 static void pnfs_recall_all_layouts(struct nfs_client *clp,
359 				    struct cb_process_state *cps)
360 {
361 	struct cb_layoutrecallargs args;
362 
363 	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
364 	memset(&args, 0, sizeof(args));
365 	args.cbl_recall_type = RETURN_ALL;
366 	/* FIXME we ignore errors, what should we do? */
367 	do_callback_layoutrecall(clp, &args, cps);
368 }
369 
370 __be32 nfs4_callback_devicenotify(void *argp, void *resp,
371 				  struct cb_process_state *cps)
372 {
373 	struct cb_devicenotifyargs *args = argp;
374 	const struct pnfs_layoutdriver_type *ld = NULL;
375 	uint32_t i;
376 	__be32 res = 0;
377 
378 	if (!cps->clp) {
379 		res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
380 		goto out;
381 	}
382 
383 	for (i = 0; i < args->ndevs; i++) {
384 		struct cb_devicenotifyitem *dev = &args->devs[i];
385 
386 		if (!ld || ld->id != dev->cbd_layout_type) {
387 			pnfs_put_layoutdriver(ld);
388 			ld = pnfs_find_layoutdriver(dev->cbd_layout_type);
389 			if (!ld)
390 				continue;
391 		}
392 		nfs4_delete_deviceid(ld, cps->clp, &dev->cbd_dev_id);
393 	}
394 	pnfs_put_layoutdriver(ld);
395 out:
396 	kfree(args->devs);
397 	return res;
398 }
399 
400 /*
401  * Validate the sequenceID sent by the server.
402  * Return success if the sequenceID is one more than what we last saw on
403  * this slot, accounting for wraparound.  Increments the slot's sequence.
404  *
405  * We don't yet implement a duplicate request cache, instead we set the
406  * back channel ca_maxresponsesize_cached to zero. This is OK for now
407  * since we only currently implement idempotent callbacks anyway.
408  *
409  * We have a single slot backchannel at this time, so we don't bother
410  * checking the used_slots bit array on the table.  The lower layer guarantees
411  * a single outstanding callback request at a time.
412  */
413 static __be32
414 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
415 		const struct cb_sequenceargs * args)
416 {
417 	__be32 ret;
418 
419 	ret = cpu_to_be32(NFS4ERR_BADSLOT);
420 	if (args->csa_slotid > tbl->server_highest_slotid)
421 		goto out_err;
422 
423 	/* Replay */
424 	if (args->csa_sequenceid == slot->seq_nr) {
425 		ret = cpu_to_be32(NFS4ERR_DELAY);
426 		if (nfs4_test_locked_slot(tbl, slot->slot_nr))
427 			goto out_err;
428 
429 		/* Signal process_op to set this error on next op */
430 		ret = cpu_to_be32(NFS4ERR_RETRY_UNCACHED_REP);
431 		if (args->csa_cachethis == 0)
432 			goto out_err;
433 
434 		/* Liar! We never allowed you to set csa_cachethis != 0 */
435 		ret = cpu_to_be32(NFS4ERR_SEQ_FALSE_RETRY);
436 		goto out_err;
437 	}
438 
439 	/* Note: wraparound relies on seq_nr being of type u32 */
440 	/* Misordered request */
441 	ret = cpu_to_be32(NFS4ERR_SEQ_MISORDERED);
442 	if (args->csa_sequenceid != slot->seq_nr + 1)
443 		goto out_err;
444 
445 	return cpu_to_be32(NFS4_OK);
446 
447 out_err:
448 	trace_nfs4_cb_seqid_err(args, ret);
449 	return ret;
450 }
451 
452 /*
453  * For each referring call triple, check the session's slot table for
454  * a match.  If the slot is in use and the sequence numbers match, the
455  * client is still waiting for a response to the original request.
456  */
457 static int referring_call_exists(struct nfs_client *clp,
458 				  uint32_t nrclists,
459 				  struct referring_call_list *rclists,
460 				  spinlock_t *lock)
461 	__releases(lock)
462 	__acquires(lock)
463 {
464 	int status = 0;
465 	int found = 0;
466 	int i, j;
467 	struct nfs4_session *session;
468 	struct nfs4_slot_table *tbl;
469 	struct referring_call_list *rclist;
470 	struct referring_call *ref;
471 
472 	/*
473 	 * XXX When client trunking is implemented, this becomes
474 	 * a session lookup from within the loop
475 	 */
476 	session = clp->cl_session;
477 	tbl = &session->fc_slot_table;
478 
479 	for (i = 0; i < nrclists; i++) {
480 		rclist = &rclists[i];
481 		if (memcmp(session->sess_id.data,
482 			   rclist->rcl_sessionid.data,
483 			   NFS4_MAX_SESSIONID_LEN) != 0)
484 			continue;
485 
486 		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
487 			ref = &rclist->rcl_refcalls[j];
488 			spin_unlock(lock);
489 			status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
490 					ref->rc_sequenceid, HZ >> 1) < 0;
491 			spin_lock(lock);
492 			if (status)
493 				goto out;
494 			found++;
495 		}
496 	}
497 
498 out:
499 	return status < 0 ? status : found;
500 }
501 
502 __be32 nfs4_callback_sequence(void *argp, void *resp,
503 			      struct cb_process_state *cps)
504 {
505 	struct cb_sequenceargs *args = argp;
506 	struct cb_sequenceres *res = resp;
507 	struct nfs4_slot_table *tbl;
508 	struct nfs4_slot *slot;
509 	struct nfs_client *clp;
510 	int ret;
511 	int i;
512 	__be32 status = htonl(NFS4ERR_BADSESSION);
513 
514 	clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
515 					 &args->csa_sessionid, cps->minorversion);
516 	if (clp == NULL)
517 		goto out;
518 
519 	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
520 		goto out;
521 
522 	tbl = &clp->cl_session->bc_slot_table;
523 
524 	/* Set up res before grabbing the spinlock */
525 	memcpy(&res->csr_sessionid, &args->csa_sessionid,
526 	       sizeof(res->csr_sessionid));
527 	res->csr_sequenceid = args->csa_sequenceid;
528 	res->csr_slotid = args->csa_slotid;
529 
530 	spin_lock(&tbl->slot_tbl_lock);
531 	/* state manager is resetting the session */
532 	if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
533 		status = htonl(NFS4ERR_DELAY);
534 		/* Return NFS4ERR_BADSESSION if we're draining the session
535 		 * in order to reset it.
536 		 */
537 		if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
538 			status = htonl(NFS4ERR_BADSESSION);
539 		goto out_unlock;
540 	}
541 
542 	status = htonl(NFS4ERR_BADSLOT);
543 	slot = nfs4_lookup_slot(tbl, args->csa_slotid);
544 	if (IS_ERR(slot))
545 		goto out_unlock;
546 
547 	res->csr_highestslotid = tbl->server_highest_slotid;
548 	res->csr_target_highestslotid = tbl->target_highest_slotid;
549 
550 	status = validate_seqid(tbl, slot, args);
551 	if (status)
552 		goto out_unlock;
553 	if (!nfs4_try_to_lock_slot(tbl, slot)) {
554 		status = htonl(NFS4ERR_DELAY);
555 		goto out_unlock;
556 	}
557 	cps->slot = slot;
558 
559 	/* The ca_maxresponsesize_cached is 0 with no DRC */
560 	if (args->csa_cachethis != 0) {
561 		status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
562 		goto out_unlock;
563 	}
564 
565 	/*
566 	 * Check for pending referring calls.  If a match is found, a
567 	 * related callback was received before the response to the original
568 	 * call.
569 	 */
570 	ret = referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
571 				    &tbl->slot_tbl_lock);
572 	if (ret < 0) {
573 		status = htonl(NFS4ERR_DELAY);
574 		goto out_unlock;
575 	}
576 	cps->referring_calls = ret;
577 
578 	/*
579 	 * RFC5661 20.9.3
580 	 * If CB_SEQUENCE returns an error, then the state of the slot
581 	 * (sequence ID, cached reply) MUST NOT change.
582 	 */
583 	slot->seq_nr = args->csa_sequenceid;
584 out_unlock:
585 	spin_unlock(&tbl->slot_tbl_lock);
586 
587 out:
588 	cps->clp = clp; /* put in nfs4_callback_compound */
589 	for (i = 0; i < args->csa_nrclists; i++)
590 		kfree(args->csa_rclists[i].rcl_refcalls);
591 	kfree(args->csa_rclists);
592 
593 	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
594 		cps->drc_status = status;
595 		status = 0;
596 	} else
597 		res->csr_status = status;
598 
599 	trace_nfs4_cb_sequence(args, res, status);
600 	return status;
601 }
602 
603 static bool
604 validate_bitmap_values(unsigned int mask)
605 {
606 	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
607 }
608 
609 __be32 nfs4_callback_recallany(void *argp, void *resp,
610 			       struct cb_process_state *cps)
611 {
612 	struct cb_recallanyargs *args = argp;
613 	__be32 status;
614 	fmode_t flags = 0;
615 	bool schedule_manager = false;
616 
617 	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
618 	if (!cps->clp) /* set in cb_sequence */
619 		goto out;
620 
621 	dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
622 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
623 
624 	status = cpu_to_be32(NFS4ERR_INVAL);
625 	if (!validate_bitmap_values(args->craa_type_mask))
626 		goto out;
627 
628 	status = cpu_to_be32(NFS4_OK);
629 	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
630 		flags = FMODE_READ;
631 	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
632 		flags |= FMODE_WRITE;
633 	if (flags)
634 		nfs_expire_unused_delegation_types(cps->clp, flags);
635 
636 	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
637 		pnfs_recall_all_layouts(cps->clp, cps);
638 
639 	if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_READ)) {
640 		set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &cps->clp->cl_state);
641 		schedule_manager = true;
642 	}
643 	if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_RW)) {
644 		set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &cps->clp->cl_state);
645 		schedule_manager = true;
646 	}
647 	if (schedule_manager)
648 		nfs4_schedule_state_manager(cps->clp);
649 
650 out:
651 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
652 	return status;
653 }
654 
655 /* Reduce the fore channel's max_slots to the target value */
656 __be32 nfs4_callback_recallslot(void *argp, void *resp,
657 				struct cb_process_state *cps)
658 {
659 	struct cb_recallslotargs *args = argp;
660 	struct nfs4_slot_table *fc_tbl;
661 	__be32 status;
662 
663 	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
664 	if (!cps->clp) /* set in cb_sequence */
665 		goto out;
666 
667 	dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
668 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
669 		args->crsa_target_highest_slotid);
670 
671 	fc_tbl = &cps->clp->cl_session->fc_slot_table;
672 
673 	status = htonl(NFS4_OK);
674 
675 	nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
676 	nfs41_notify_server(cps->clp);
677 out:
678 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
679 	return status;
680 }
681 
682 __be32 nfs4_callback_notify_lock(void *argp, void *resp,
683 				 struct cb_process_state *cps)
684 {
685 	struct cb_notify_lock_args *args = argp;
686 
687 	if (!cps->clp) /* set in cb_sequence */
688 		return htonl(NFS4ERR_OP_NOT_IN_SESSION);
689 
690 	dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
691 		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
692 
693 	/* Don't wake anybody if the string looked bogus */
694 	if (args->cbnl_valid)
695 		__wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
696 
697 	return htonl(NFS4_OK);
698 }
699 #ifdef CONFIG_NFS_V4_2
700 static void nfs4_copy_cb_args(struct nfs4_copy_state *cp_state,
701 				struct cb_offloadargs *args)
702 {
703 	cp_state->count = args->wr_count;
704 	cp_state->error = args->error;
705 	if (!args->error) {
706 		cp_state->verf.committed = args->wr_writeverf.committed;
707 		memcpy(&cp_state->verf.verifier.data[0],
708 			&args->wr_writeverf.verifier.data[0],
709 			NFS4_VERIFIER_SIZE);
710 	}
711 }
712 
713 __be32 nfs4_callback_offload(void *data, void *dummy,
714 			     struct cb_process_state *cps)
715 {
716 	struct cb_offloadargs *args = data;
717 	struct nfs_server *server;
718 	struct nfs4_copy_state *copy, *tmp_copy;
719 	bool found = false;
720 
721 	copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_KERNEL);
722 	if (!copy)
723 		return cpu_to_be32(NFS4ERR_DELAY);
724 
725 	spin_lock(&cps->clp->cl_lock);
726 	rcu_read_lock();
727 	list_for_each_entry_rcu(server, &cps->clp->cl_superblocks,
728 				client_link) {
729 		list_for_each_entry(tmp_copy, &server->ss_copies, copies) {
730 			if (memcmp(args->coa_stateid.other,
731 					tmp_copy->stateid.other,
732 					sizeof(args->coa_stateid.other)))
733 				continue;
734 			nfs4_copy_cb_args(tmp_copy, args);
735 			complete(&tmp_copy->completion);
736 			found = true;
737 			goto out;
738 		}
739 	}
740 out:
741 	rcu_read_unlock();
742 	if (!found) {
743 		memcpy(&copy->stateid, &args->coa_stateid, NFS4_STATEID_SIZE);
744 		nfs4_copy_cb_args(copy, args);
745 		list_add_tail(&copy->copies, &cps->clp->pending_cb_stateids);
746 	} else
747 		kfree(copy);
748 	spin_unlock(&cps->clp->cl_lock);
749 
750 	trace_nfs4_cb_offload(&args->coa_fh, &args->coa_stateid,
751 			args->wr_count, args->error,
752 			args->wr_writeverf.committed);
753 	return 0;
754 }
755 #endif /* CONFIG_NFS_V4_2 */
756