xref: /kernel/linux/linux-5.10/fs/nfs/callback_proc.c (revision 8c2ecf20)
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#include <linux/nfs4.h>
10#include <linux/nfs_fs.h>
11#include <linux/slab.h>
12#include <linux/rcupdate.h>
13#include "nfs4_fs.h"
14#include "callback.h"
15#include "delegation.h"
16#include "internal.h"
17#include "pnfs.h"
18#include "nfs4session.h"
19#include "nfs4trace.h"
20
21#define NFSDBG_FACILITY NFSDBG_CALLBACK
22
23__be32 nfs4_callback_getattr(void *argp, void *resp,
24			     struct cb_process_state *cps)
25{
26	struct cb_getattrargs *args = argp;
27	struct cb_getattrres *res = resp;
28	struct nfs_delegation *delegation;
29	struct inode *inode;
30
31	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
32	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
33		goto out;
34
35	res->bitmap[0] = res->bitmap[1] = 0;
36	res->status = htonl(NFS4ERR_BADHANDLE);
37
38	dprintk_rcu("NFS: GETATTR callback request from %s\n",
39		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
40
41	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
42	if (IS_ERR(inode)) {
43		if (inode == ERR_PTR(-EAGAIN))
44			res->status = htonl(NFS4ERR_DELAY);
45		trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
46				-ntohl(res->status));
47		goto out;
48	}
49	rcu_read_lock();
50	delegation = nfs4_get_valid_delegation(inode);
51	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
52		goto out_iput;
53	res->size = i_size_read(inode);
54	res->change_attr = delegation->change_attr;
55	if (nfs_have_writebacks(inode))
56		res->change_attr++;
57	res->ctime = inode->i_ctime;
58	res->mtime = inode->i_mtime;
59	res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
60		args->bitmap[0];
61	res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
62		args->bitmap[1];
63	res->status = 0;
64out_iput:
65	rcu_read_unlock();
66	trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
67	nfs_iput_and_deactive(inode);
68out:
69	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
70	return res->status;
71}
72
73__be32 nfs4_callback_recall(void *argp, void *resp,
74			    struct cb_process_state *cps)
75{
76	struct cb_recallargs *args = argp;
77	struct inode *inode;
78	__be32 res;
79
80	res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
81	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
82		goto out;
83
84	dprintk_rcu("NFS: RECALL callback request from %s\n",
85		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
86
87	res = htonl(NFS4ERR_BADHANDLE);
88	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
89	if (IS_ERR(inode)) {
90		if (inode == ERR_PTR(-EAGAIN))
91			res = htonl(NFS4ERR_DELAY);
92		trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
93				&args->stateid, -ntohl(res));
94		goto out;
95	}
96	/* Set up a helper thread to actually return the delegation */
97	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
98	case 0:
99		res = 0;
100		break;
101	case -ENOENT:
102		res = htonl(NFS4ERR_BAD_STATEID);
103		break;
104	default:
105		res = htonl(NFS4ERR_RESOURCE);
106	}
107	trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
108			&args->stateid, -ntohl(res));
109	nfs_iput_and_deactive(inode);
110out:
111	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
112	return res;
113}
114
115#if defined(CONFIG_NFS_V4_1)
116
117/*
118 * Lookup a layout inode by stateid
119 *
120 * Note: returns a refcount on the inode and superblock
121 */
122static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
123		const nfs4_stateid *stateid)
124	__must_hold(RCU)
125{
126	struct nfs_server *server;
127	struct inode *inode;
128	struct pnfs_layout_hdr *lo;
129
130	rcu_read_lock();
131	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
132		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
133			if (!pnfs_layout_is_valid(lo))
134				continue;
135			if (!nfs4_stateid_match_other(stateid, &lo->plh_stateid))
136				continue;
137			if (nfs_sb_active(server->super))
138				inode = igrab(lo->plh_inode);
139			else
140				inode = ERR_PTR(-EAGAIN);
141			rcu_read_unlock();
142			if (inode)
143				return inode;
144			nfs_sb_deactive(server->super);
145			return ERR_PTR(-EAGAIN);
146		}
147	}
148	rcu_read_unlock();
149	return ERR_PTR(-ENOENT);
150}
151
152/*
153 * Lookup a layout inode by filehandle.
154 *
155 * Note: returns a refcount on the inode and superblock
156 *
157 */
158static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
159		const struct nfs_fh *fh)
160{
161	struct nfs_server *server;
162	struct nfs_inode *nfsi;
163	struct inode *inode;
164	struct pnfs_layout_hdr *lo;
165
166	rcu_read_lock();
167	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
168		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
169			nfsi = NFS_I(lo->plh_inode);
170			if (nfs_compare_fh(fh, &nfsi->fh))
171				continue;
172			if (nfsi->layout != lo)
173				continue;
174			if (nfs_sb_active(server->super))
175				inode = igrab(lo->plh_inode);
176			else
177				inode = ERR_PTR(-EAGAIN);
178			rcu_read_unlock();
179			if (inode)
180				return inode;
181			nfs_sb_deactive(server->super);
182			return ERR_PTR(-EAGAIN);
183		}
184	}
185	rcu_read_unlock();
186	return ERR_PTR(-ENOENT);
187}
188
189static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
190		const struct nfs_fh *fh,
191		const nfs4_stateid *stateid)
192{
193	struct inode *inode;
194
195	inode = nfs_layout_find_inode_by_stateid(clp, stateid);
196	if (inode == ERR_PTR(-ENOENT))
197		inode = nfs_layout_find_inode_by_fh(clp, fh);
198	return inode;
199}
200
201/*
202 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
203 */
204static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
205					const nfs4_stateid *new)
206{
207	u32 oldseq, newseq;
208
209	/* Is the stateid not initialised? */
210	if (!pnfs_layout_is_valid(lo))
211		return NFS4ERR_NOMATCHING_LAYOUT;
212
213	/* Mismatched stateid? */
214	if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
215		return NFS4ERR_BAD_STATEID;
216
217	newseq = be32_to_cpu(new->seqid);
218	/* Are we already in a layout recall situation? */
219	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
220	    lo->plh_return_seq != 0) {
221		if (newseq < lo->plh_return_seq)
222			return NFS4ERR_OLD_STATEID;
223		if (newseq > lo->plh_return_seq)
224			return NFS4ERR_DELAY;
225		goto out;
226	}
227
228	/* Check that the stateid matches what we think it should be. */
229	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
230	if (newseq > oldseq + 1)
231		return NFS4ERR_DELAY;
232	/* Crazy server! */
233	if (newseq <= oldseq)
234		return NFS4ERR_OLD_STATEID;
235out:
236	return NFS_OK;
237}
238
239static u32 initiate_file_draining(struct nfs_client *clp,
240				  struct cb_layoutrecallargs *args)
241{
242	struct inode *ino;
243	struct pnfs_layout_hdr *lo;
244	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
245	LIST_HEAD(free_me_list);
246
247	ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
248	if (IS_ERR(ino)) {
249		if (ino == ERR_PTR(-EAGAIN))
250			rv = NFS4ERR_DELAY;
251		goto out_noput;
252	}
253
254	pnfs_layoutcommit_inode(ino, false);
255
256
257	spin_lock(&ino->i_lock);
258	lo = NFS_I(ino)->layout;
259	if (!lo) {
260		spin_unlock(&ino->i_lock);
261		goto out;
262	}
263	pnfs_get_layout_hdr(lo);
264	rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid);
265	if (rv != NFS_OK)
266		goto unlock;
267
268	/*
269	 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
270	 */
271	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
272		rv = NFS4ERR_DELAY;
273		goto unlock;
274	}
275
276	pnfs_set_layout_stateid(lo, &args->cbl_stateid, NULL, true);
277	switch (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
278				&args->cbl_range,
279				be32_to_cpu(args->cbl_stateid.seqid))) {
280	case 0:
281	case -EBUSY:
282		/* There are layout segments that need to be returned */
283		rv = NFS4_OK;
284		break;
285	case -ENOENT:
286		set_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags);
287		/* Embrace your forgetfulness! */
288		rv = NFS4ERR_NOMATCHING_LAYOUT;
289
290		if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
291			NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
292				&args->cbl_range);
293		}
294	}
295unlock:
296	spin_unlock(&ino->i_lock);
297	pnfs_free_lseg_list(&free_me_list);
298	/* Free all lsegs that are attached to commit buckets */
299	nfs_commit_inode(ino, 0);
300	pnfs_put_layout_hdr(lo);
301out:
302	nfs_iput_and_deactive(ino);
303out_noput:
304	trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
305			&args->cbl_stateid, -rv);
306	return rv;
307}
308
309static u32 initiate_bulk_draining(struct nfs_client *clp,
310				  struct cb_layoutrecallargs *args)
311{
312	int stat;
313
314	if (args->cbl_recall_type == RETURN_FSID)
315		stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
316	else
317		stat = pnfs_destroy_layouts_byclid(clp, true);
318	if (stat != 0)
319		return NFS4ERR_DELAY;
320	return NFS4ERR_NOMATCHING_LAYOUT;
321}
322
323static u32 do_callback_layoutrecall(struct nfs_client *clp,
324				    struct cb_layoutrecallargs *args)
325{
326	if (args->cbl_recall_type == RETURN_FILE)
327		return initiate_file_draining(clp, args);
328	return initiate_bulk_draining(clp, args);
329}
330
331__be32 nfs4_callback_layoutrecall(void *argp, void *resp,
332				  struct cb_process_state *cps)
333{
334	struct cb_layoutrecallargs *args = argp;
335	u32 res = NFS4ERR_OP_NOT_IN_SESSION;
336
337	if (cps->clp)
338		res = do_callback_layoutrecall(cps->clp, args);
339	return cpu_to_be32(res);
340}
341
342static void pnfs_recall_all_layouts(struct nfs_client *clp)
343{
344	struct cb_layoutrecallargs args;
345
346	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
347	memset(&args, 0, sizeof(args));
348	args.cbl_recall_type = RETURN_ALL;
349	/* FIXME we ignore errors, what should we do? */
350	do_callback_layoutrecall(clp, &args);
351}
352
353__be32 nfs4_callback_devicenotify(void *argp, void *resp,
354				  struct cb_process_state *cps)
355{
356	struct cb_devicenotifyargs *args = argp;
357	const struct pnfs_layoutdriver_type *ld = NULL;
358	uint32_t i;
359	__be32 res = 0;
360
361	if (!cps->clp) {
362		res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
363		goto out;
364	}
365
366	for (i = 0; i < args->ndevs; i++) {
367		struct cb_devicenotifyitem *dev = &args->devs[i];
368
369		if (!ld || ld->id != dev->cbd_layout_type) {
370			pnfs_put_layoutdriver(ld);
371			ld = pnfs_find_layoutdriver(dev->cbd_layout_type);
372			if (!ld)
373				continue;
374		}
375		nfs4_delete_deviceid(ld, cps->clp, &dev->cbd_dev_id);
376	}
377	pnfs_put_layoutdriver(ld);
378out:
379	kfree(args->devs);
380	return res;
381}
382
383/*
384 * Validate the sequenceID sent by the server.
385 * Return success if the sequenceID is one more than what we last saw on
386 * this slot, accounting for wraparound.  Increments the slot's sequence.
387 *
388 * We don't yet implement a duplicate request cache, instead we set the
389 * back channel ca_maxresponsesize_cached to zero. This is OK for now
390 * since we only currently implement idempotent callbacks anyway.
391 *
392 * We have a single slot backchannel at this time, so we don't bother
393 * checking the used_slots bit array on the table.  The lower layer guarantees
394 * a single outstanding callback request at a time.
395 */
396static __be32
397validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
398		const struct cb_sequenceargs * args)
399{
400	__be32 ret;
401
402	ret = cpu_to_be32(NFS4ERR_BADSLOT);
403	if (args->csa_slotid > tbl->server_highest_slotid)
404		goto out_err;
405
406	/* Replay */
407	if (args->csa_sequenceid == slot->seq_nr) {
408		ret = cpu_to_be32(NFS4ERR_DELAY);
409		if (nfs4_test_locked_slot(tbl, slot->slot_nr))
410			goto out_err;
411
412		/* Signal process_op to set this error on next op */
413		ret = cpu_to_be32(NFS4ERR_RETRY_UNCACHED_REP);
414		if (args->csa_cachethis == 0)
415			goto out_err;
416
417		/* Liar! We never allowed you to set csa_cachethis != 0 */
418		ret = cpu_to_be32(NFS4ERR_SEQ_FALSE_RETRY);
419		goto out_err;
420	}
421
422	/* Note: wraparound relies on seq_nr being of type u32 */
423	/* Misordered request */
424	ret = cpu_to_be32(NFS4ERR_SEQ_MISORDERED);
425	if (args->csa_sequenceid != slot->seq_nr + 1)
426		goto out_err;
427
428	return cpu_to_be32(NFS4_OK);
429
430out_err:
431	trace_nfs4_cb_seqid_err(args, ret);
432	return ret;
433}
434
435/*
436 * For each referring call triple, check the session's slot table for
437 * a match.  If the slot is in use and the sequence numbers match, the
438 * client is still waiting for a response to the original request.
439 */
440static int referring_call_exists(struct nfs_client *clp,
441				  uint32_t nrclists,
442				  struct referring_call_list *rclists,
443				  spinlock_t *lock)
444	__releases(lock)
445	__acquires(lock)
446{
447	int status = 0;
448	int i, j;
449	struct nfs4_session *session;
450	struct nfs4_slot_table *tbl;
451	struct referring_call_list *rclist;
452	struct referring_call *ref;
453
454	/*
455	 * XXX When client trunking is implemented, this becomes
456	 * a session lookup from within the loop
457	 */
458	session = clp->cl_session;
459	tbl = &session->fc_slot_table;
460
461	for (i = 0; i < nrclists; i++) {
462		rclist = &rclists[i];
463		if (memcmp(session->sess_id.data,
464			   rclist->rcl_sessionid.data,
465			   NFS4_MAX_SESSIONID_LEN) != 0)
466			continue;
467
468		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
469			ref = &rclist->rcl_refcalls[j];
470			spin_unlock(lock);
471			status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
472					ref->rc_sequenceid, HZ >> 1) < 0;
473			spin_lock(lock);
474			if (status)
475				goto out;
476		}
477	}
478
479out:
480	return status;
481}
482
483__be32 nfs4_callback_sequence(void *argp, void *resp,
484			      struct cb_process_state *cps)
485{
486	struct cb_sequenceargs *args = argp;
487	struct cb_sequenceres *res = resp;
488	struct nfs4_slot_table *tbl;
489	struct nfs4_slot *slot;
490	struct nfs_client *clp;
491	int i;
492	__be32 status = htonl(NFS4ERR_BADSESSION);
493
494	clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
495					 &args->csa_sessionid, cps->minorversion);
496	if (clp == NULL)
497		goto out;
498
499	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
500		goto out;
501
502	tbl = &clp->cl_session->bc_slot_table;
503
504	/* Set up res before grabbing the spinlock */
505	memcpy(&res->csr_sessionid, &args->csa_sessionid,
506	       sizeof(res->csr_sessionid));
507	res->csr_sequenceid = args->csa_sequenceid;
508	res->csr_slotid = args->csa_slotid;
509
510	spin_lock(&tbl->slot_tbl_lock);
511	/* state manager is resetting the session */
512	if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
513		status = htonl(NFS4ERR_DELAY);
514		/* Return NFS4ERR_BADSESSION if we're draining the session
515		 * in order to reset it.
516		 */
517		if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
518			status = htonl(NFS4ERR_BADSESSION);
519		goto out_unlock;
520	}
521
522	status = htonl(NFS4ERR_BADSLOT);
523	slot = nfs4_lookup_slot(tbl, args->csa_slotid);
524	if (IS_ERR(slot))
525		goto out_unlock;
526
527	res->csr_highestslotid = tbl->server_highest_slotid;
528	res->csr_target_highestslotid = tbl->target_highest_slotid;
529
530	status = validate_seqid(tbl, slot, args);
531	if (status)
532		goto out_unlock;
533	if (!nfs4_try_to_lock_slot(tbl, slot)) {
534		status = htonl(NFS4ERR_DELAY);
535		goto out_unlock;
536	}
537	cps->slot = slot;
538
539	/* The ca_maxresponsesize_cached is 0 with no DRC */
540	if (args->csa_cachethis != 0) {
541		status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
542		goto out_unlock;
543	}
544
545	/*
546	 * Check for pending referring calls.  If a match is found, a
547	 * related callback was received before the response to the original
548	 * call.
549	 */
550	if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
551				&tbl->slot_tbl_lock) < 0) {
552		status = htonl(NFS4ERR_DELAY);
553		goto out_unlock;
554	}
555
556	/*
557	 * RFC5661 20.9.3
558	 * If CB_SEQUENCE returns an error, then the state of the slot
559	 * (sequence ID, cached reply) MUST NOT change.
560	 */
561	slot->seq_nr = args->csa_sequenceid;
562out_unlock:
563	spin_unlock(&tbl->slot_tbl_lock);
564
565out:
566	cps->clp = clp; /* put in nfs4_callback_compound */
567	for (i = 0; i < args->csa_nrclists; i++)
568		kfree(args->csa_rclists[i].rcl_refcalls);
569	kfree(args->csa_rclists);
570
571	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
572		cps->drc_status = status;
573		status = 0;
574	} else
575		res->csr_status = status;
576
577	trace_nfs4_cb_sequence(args, res, status);
578	return status;
579}
580
581static bool
582validate_bitmap_values(unsigned int mask)
583{
584	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
585}
586
587__be32 nfs4_callback_recallany(void *argp, void *resp,
588			       struct cb_process_state *cps)
589{
590	struct cb_recallanyargs *args = argp;
591	__be32 status;
592	fmode_t flags = 0;
593	bool schedule_manager = false;
594
595	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
596	if (!cps->clp) /* set in cb_sequence */
597		goto out;
598
599	dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
600		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
601
602	status = cpu_to_be32(NFS4ERR_INVAL);
603	if (!validate_bitmap_values(args->craa_type_mask))
604		goto out;
605
606	status = cpu_to_be32(NFS4_OK);
607	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
608		flags = FMODE_READ;
609	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
610		flags |= FMODE_WRITE;
611	if (flags)
612		nfs_expire_unused_delegation_types(cps->clp, flags);
613
614	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
615		pnfs_recall_all_layouts(cps->clp);
616
617	if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_READ)) {
618		set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &cps->clp->cl_state);
619		schedule_manager = true;
620	}
621	if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_RW)) {
622		set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &cps->clp->cl_state);
623		schedule_manager = true;
624	}
625	if (schedule_manager)
626		nfs4_schedule_state_manager(cps->clp);
627
628out:
629	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
630	return status;
631}
632
633/* Reduce the fore channel's max_slots to the target value */
634__be32 nfs4_callback_recallslot(void *argp, void *resp,
635				struct cb_process_state *cps)
636{
637	struct cb_recallslotargs *args = argp;
638	struct nfs4_slot_table *fc_tbl;
639	__be32 status;
640
641	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
642	if (!cps->clp) /* set in cb_sequence */
643		goto out;
644
645	dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
646		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
647		args->crsa_target_highest_slotid);
648
649	fc_tbl = &cps->clp->cl_session->fc_slot_table;
650
651	status = htonl(NFS4_OK);
652
653	nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
654	nfs41_notify_server(cps->clp);
655out:
656	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
657	return status;
658}
659
660__be32 nfs4_callback_notify_lock(void *argp, void *resp,
661				 struct cb_process_state *cps)
662{
663	struct cb_notify_lock_args *args = argp;
664
665	if (!cps->clp) /* set in cb_sequence */
666		return htonl(NFS4ERR_OP_NOT_IN_SESSION);
667
668	dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
669		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
670
671	/* Don't wake anybody if the string looked bogus */
672	if (args->cbnl_valid)
673		__wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
674
675	return htonl(NFS4_OK);
676}
677#endif /* CONFIG_NFS_V4_1 */
678#ifdef CONFIG_NFS_V4_2
679static void nfs4_copy_cb_args(struct nfs4_copy_state *cp_state,
680				struct cb_offloadargs *args)
681{
682	cp_state->count = args->wr_count;
683	cp_state->error = args->error;
684	if (!args->error) {
685		cp_state->verf.committed = args->wr_writeverf.committed;
686		memcpy(&cp_state->verf.verifier.data[0],
687			&args->wr_writeverf.verifier.data[0],
688			NFS4_VERIFIER_SIZE);
689	}
690}
691
692__be32 nfs4_callback_offload(void *data, void *dummy,
693			     struct cb_process_state *cps)
694{
695	struct cb_offloadargs *args = data;
696	struct nfs_server *server;
697	struct nfs4_copy_state *copy, *tmp_copy;
698	bool found = false;
699
700	copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_NOFS);
701	if (!copy)
702		return htonl(NFS4ERR_SERVERFAULT);
703
704	spin_lock(&cps->clp->cl_lock);
705	rcu_read_lock();
706	list_for_each_entry_rcu(server, &cps->clp->cl_superblocks,
707				client_link) {
708		list_for_each_entry(tmp_copy, &server->ss_copies, copies) {
709			if (memcmp(args->coa_stateid.other,
710					tmp_copy->stateid.other,
711					sizeof(args->coa_stateid.other)))
712				continue;
713			nfs4_copy_cb_args(tmp_copy, args);
714			complete(&tmp_copy->completion);
715			found = true;
716			goto out;
717		}
718	}
719out:
720	rcu_read_unlock();
721	if (!found) {
722		memcpy(&copy->stateid, &args->coa_stateid, NFS4_STATEID_SIZE);
723		nfs4_copy_cb_args(copy, args);
724		list_add_tail(&copy->copies, &cps->clp->pending_cb_stateids);
725	} else
726		kfree(copy);
727	spin_unlock(&cps->clp->cl_lock);
728
729	return 0;
730}
731#endif /* CONFIG_NFS_V4_2 */
732