Linux Audio

Check our new training course

In-person Linux kernel drivers training

Jun 16-20, 2025
Register
Loading...
v4.17
  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 nfs_inode *nfsi;
 30	struct inode *inode;
 31
 32	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
 33	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
 34		goto out;
 35
 36	res->bitmap[0] = res->bitmap[1] = 0;
 37	res->status = htonl(NFS4ERR_BADHANDLE);
 38
 39	dprintk_rcu("NFS: GETATTR callback request from %s\n",
 40		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 41
 42	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
 43	if (inode == NULL) {
 
 
 44		trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
 45				-ntohl(res->status));
 46		goto out;
 47	}
 48	nfsi = NFS_I(inode);
 49	rcu_read_lock();
 50	delegation = rcu_dereference(nfsi->delegation);
 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	iput(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 (inode == NULL) {
 
 
 90		trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
 91				&args->stateid, -ntohl(res));
 92		goto out;
 93	}
 94	/* Set up a helper thread to actually return the delegation */
 95	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
 96	case 0:
 97		res = 0;
 98		break;
 99	case -ENOENT:
100		res = htonl(NFS4ERR_BAD_STATEID);
101		break;
102	default:
103		res = htonl(NFS4ERR_RESOURCE);
104	}
105	trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
106			&args->stateid, -ntohl(res));
107	iput(inode);
108out:
109	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
110	return res;
111}
112
113#if defined(CONFIG_NFS_V4_1)
114
115/*
116 * Lookup a layout inode by stateid
117 *
118 * Note: returns a refcount on the inode and superblock
119 */
120static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
121		const nfs4_stateid *stateid)
 
122{
123	struct nfs_server *server;
124	struct inode *inode;
125	struct pnfs_layout_hdr *lo;
126
127restart:
128	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
129		list_for_each_entry(lo, &server->layouts, plh_layouts) {
130			if (stateid != NULL &&
131			    !nfs4_stateid_match_other(stateid, &lo->plh_stateid))
132				continue;
133			inode = igrab(lo->plh_inode);
134			if (!inode)
135				continue;
136			if (!nfs_sb_active(inode->i_sb)) {
137				rcu_read_unlock();
138				spin_unlock(&clp->cl_lock);
139				iput(inode);
140				spin_lock(&clp->cl_lock);
141				rcu_read_lock();
142				goto restart;
143			}
144			return inode;
145		}
146	}
147
148	return NULL;
149}
150
151/*
152 * Lookup a layout inode by filehandle.
153 *
154 * Note: returns a refcount on the inode and superblock
155 *
156 */
157static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
158		const struct nfs_fh *fh)
159{
160	struct nfs_server *server;
161	struct nfs_inode *nfsi;
162	struct inode *inode;
163	struct pnfs_layout_hdr *lo;
164
165restart:
166	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
167		list_for_each_entry(lo, &server->layouts, plh_layouts) {
168			nfsi = NFS_I(lo->plh_inode);
169			if (nfs_compare_fh(fh, &nfsi->fh))
170				continue;
171			if (nfsi->layout != lo)
172				continue;
173			inode = igrab(lo->plh_inode);
174			if (!inode)
175				continue;
176			if (!nfs_sb_active(inode->i_sb)) {
177				rcu_read_unlock();
178				spin_unlock(&clp->cl_lock);
179				iput(inode);
180				spin_lock(&clp->cl_lock);
181				rcu_read_lock();
182				goto restart;
183			}
184			return inode;
185		}
186	}
187
188	return NULL;
189}
190
191static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
192		const struct nfs_fh *fh,
193		const nfs4_stateid *stateid)
194{
195	struct inode *inode;
196
197	spin_lock(&clp->cl_lock);
198	rcu_read_lock();
199	inode = nfs_layout_find_inode_by_stateid(clp, stateid);
200	if (!inode)
201		inode = nfs_layout_find_inode_by_fh(clp, fh);
202	rcu_read_unlock();
203	spin_unlock(&clp->cl_lock);
204
205	return inode;
206}
207
208/*
209 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
210 */
211static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
212					const nfs4_stateid *new)
213{
214	u32 oldseq, newseq;
215
216	/* Is the stateid still not initialised? */
217	if (!pnfs_layout_is_valid(lo))
218		return NFS4ERR_DELAY;
219
220	/* Mismatched stateid? */
221	if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
222		return NFS4ERR_BAD_STATEID;
223
224	newseq = be32_to_cpu(new->seqid);
225	/* Are we already in a layout recall situation? */
226	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
227	    lo->plh_return_seq != 0) {
228		if (newseq < lo->plh_return_seq)
229			return NFS4ERR_OLD_STATEID;
230		if (newseq > lo->plh_return_seq)
231			return NFS4ERR_DELAY;
232		goto out;
233	}
234
235	/* Check that the stateid matches what we think it should be. */
236	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
237	if (newseq > oldseq + 1)
238		return NFS4ERR_DELAY;
239	/* Crazy server! */
240	if (newseq <= oldseq)
241		return NFS4ERR_OLD_STATEID;
242out:
243	return NFS_OK;
244}
245
246static u32 initiate_file_draining(struct nfs_client *clp,
247				  struct cb_layoutrecallargs *args)
248{
249	struct inode *ino;
250	struct pnfs_layout_hdr *lo;
251	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
252	LIST_HEAD(free_me_list);
253
254	ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
255	if (!ino)
256		goto out;
 
 
 
257
258	pnfs_layoutcommit_inode(ino, false);
259
260
261	spin_lock(&ino->i_lock);
262	lo = NFS_I(ino)->layout;
263	if (!lo) {
264		spin_unlock(&ino->i_lock);
265		goto out;
266	}
267	pnfs_get_layout_hdr(lo);
268	rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid);
269	if (rv != NFS_OK)
270		goto unlock;
271	pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
272
273	/*
274	 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
275	 */
276	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
277		rv = NFS4ERR_DELAY;
278		goto unlock;
279	}
280
281	if (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
 
282				&args->cbl_range,
283				be32_to_cpu(args->cbl_stateid.seqid))) {
 
 
 
284		rv = NFS4_OK;
285		goto unlock;
286	}
287
288	/* Embrace your forgetfulness! */
289	rv = NFS4ERR_NOMATCHING_LAYOUT;
290
291	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
292		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
293			&args->cbl_range);
 
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	trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
303			&args->cbl_stateid, -rv);
304	nfs_iput_and_deactive(ino);
305	return rv;
306}
307
308static u32 initiate_bulk_draining(struct nfs_client *clp,
309				  struct cb_layoutrecallargs *args)
310{
311	int stat;
312
313	if (args->cbl_recall_type == RETURN_FSID)
314		stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
315	else
316		stat = pnfs_destroy_layouts_byclid(clp, true);
317	if (stat != 0)
318		return NFS4ERR_DELAY;
319	return NFS4ERR_NOMATCHING_LAYOUT;
320}
321
322static u32 do_callback_layoutrecall(struct nfs_client *clp,
323				    struct cb_layoutrecallargs *args)
324{
325	if (args->cbl_recall_type == RETURN_FILE)
326		return initiate_file_draining(clp, args);
327	return initiate_bulk_draining(clp, args);
328}
329
330__be32 nfs4_callback_layoutrecall(void *argp, void *resp,
331				  struct cb_process_state *cps)
332{
333	struct cb_layoutrecallargs *args = argp;
334	u32 res = NFS4ERR_OP_NOT_IN_SESSION;
335
336	if (cps->clp)
337		res = do_callback_layoutrecall(cps->clp, args);
338	return cpu_to_be32(res);
339}
340
341static void pnfs_recall_all_layouts(struct nfs_client *clp)
342{
343	struct cb_layoutrecallargs args;
344
345	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
346	memset(&args, 0, sizeof(args));
347	args.cbl_recall_type = RETURN_ALL;
348	/* FIXME we ignore errors, what should we do? */
349	do_callback_layoutrecall(clp, &args);
350}
351
352__be32 nfs4_callback_devicenotify(void *argp, void *resp,
353				  struct cb_process_state *cps)
354{
355	struct cb_devicenotifyargs *args = argp;
356	int i;
357	__be32 res = 0;
358	struct nfs_client *clp = cps->clp;
359	struct nfs_server *server = NULL;
360
361	if (!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 (!server ||
370		    server->pnfs_curr_ld->id != dev->cbd_layout_type) {
371			rcu_read_lock();
372			list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
373				if (server->pnfs_curr_ld &&
374				    server->pnfs_curr_ld->id == dev->cbd_layout_type) {
375					rcu_read_unlock();
376					goto found;
377				}
378			rcu_read_unlock();
379			continue;
380		}
381
382	found:
383		nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
384	}
385
386out:
387	kfree(args->devs);
388	return res;
389}
390
391/*
392 * Validate the sequenceID sent by the server.
393 * Return success if the sequenceID is one more than what we last saw on
394 * this slot, accounting for wraparound.  Increments the slot's sequence.
395 *
396 * We don't yet implement a duplicate request cache, instead we set the
397 * back channel ca_maxresponsesize_cached to zero. This is OK for now
398 * since we only currently implement idempotent callbacks anyway.
399 *
400 * We have a single slot backchannel at this time, so we don't bother
401 * checking the used_slots bit array on the table.  The lower layer guarantees
402 * a single outstanding callback request at a time.
403 */
404static __be32
405validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
406		const struct cb_sequenceargs * args)
407{
 
 
 
408	if (args->csa_slotid > tbl->server_highest_slotid)
409		return htonl(NFS4ERR_BADSLOT);
410
411	/* Replay */
412	if (args->csa_sequenceid == slot->seq_nr) {
 
413		if (nfs4_test_locked_slot(tbl, slot->slot_nr))
414			return htonl(NFS4ERR_DELAY);
 
415		/* Signal process_op to set this error on next op */
 
416		if (args->csa_cachethis == 0)
417			return htonl(NFS4ERR_RETRY_UNCACHED_REP);
418
419		/* Liar! We never allowed you to set csa_cachethis != 0 */
420		return htonl(NFS4ERR_SEQ_FALSE_RETRY);
 
421	}
422
423	/* Wraparound */
424	if (unlikely(slot->seq_nr == 0xFFFFFFFFU)) {
425		if (args->csa_sequenceid == 1)
426			return htonl(NFS4_OK);
427	} else if (likely(args->csa_sequenceid == slot->seq_nr + 1))
428		return htonl(NFS4_OK);
429
430	/* Misordered request */
431	return htonl(NFS4ERR_SEQ_MISORDERED);
 
 
 
 
 
 
 
 
432}
433
434/*
435 * For each referring call triple, check the session's slot table for
436 * a match.  If the slot is in use and the sequence numbers match, the
437 * client is still waiting for a response to the original request.
438 */
439static bool referring_call_exists(struct nfs_client *clp,
440				  uint32_t nrclists,
441				  struct referring_call_list *rclists)
 
 
 
442{
443	bool status = false;
444	int i, j;
445	struct nfs4_session *session;
446	struct nfs4_slot_table *tbl;
447	struct referring_call_list *rclist;
448	struct referring_call *ref;
449
450	/*
451	 * XXX When client trunking is implemented, this becomes
452	 * a session lookup from within the loop
453	 */
454	session = clp->cl_session;
455	tbl = &session->fc_slot_table;
456
457	for (i = 0; i < nrclists; i++) {
458		rclist = &rclists[i];
459		if (memcmp(session->sess_id.data,
460			   rclist->rcl_sessionid.data,
461			   NFS4_MAX_SESSIONID_LEN) != 0)
462			continue;
463
464		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
465			ref = &rclist->rcl_refcalls[j];
 
466			status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
467					ref->rc_sequenceid, HZ >> 1) < 0;
 
468			if (status)
469				goto out;
470		}
471	}
472
473out:
474	return status;
475}
476
477__be32 nfs4_callback_sequence(void *argp, void *resp,
478			      struct cb_process_state *cps)
479{
480	struct cb_sequenceargs *args = argp;
481	struct cb_sequenceres *res = resp;
482	struct nfs4_slot_table *tbl;
483	struct nfs4_slot *slot;
484	struct nfs_client *clp;
485	int i;
486	__be32 status = htonl(NFS4ERR_BADSESSION);
487
488	clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
489					 &args->csa_sessionid, cps->minorversion);
490	if (clp == NULL)
491		goto out;
492
493	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
494		goto out;
495
496	tbl = &clp->cl_session->bc_slot_table;
497
498	/* Set up res before grabbing the spinlock */
499	memcpy(&res->csr_sessionid, &args->csa_sessionid,
500	       sizeof(res->csr_sessionid));
501	res->csr_sequenceid = args->csa_sequenceid;
502	res->csr_slotid = args->csa_slotid;
503
504	spin_lock(&tbl->slot_tbl_lock);
505	/* state manager is resetting the session */
506	if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
507		status = htonl(NFS4ERR_DELAY);
508		/* Return NFS4ERR_BADSESSION if we're draining the session
509		 * in order to reset it.
510		 */
511		if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
512			status = htonl(NFS4ERR_BADSESSION);
513		goto out_unlock;
514	}
515
516	status = htonl(NFS4ERR_BADSLOT);
517	slot = nfs4_lookup_slot(tbl, args->csa_slotid);
518	if (IS_ERR(slot))
519		goto out_unlock;
520
521	res->csr_highestslotid = tbl->server_highest_slotid;
522	res->csr_target_highestslotid = tbl->target_highest_slotid;
523
524	status = validate_seqid(tbl, slot, args);
525	if (status)
526		goto out_unlock;
527	if (!nfs4_try_to_lock_slot(tbl, slot)) {
528		status = htonl(NFS4ERR_DELAY);
529		goto out_unlock;
530	}
531	cps->slot = slot;
532
533	/* The ca_maxresponsesize_cached is 0 with no DRC */
534	if (args->csa_cachethis != 0) {
535		status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
536		goto out_unlock;
537	}
538
539	/*
540	 * Check for pending referring calls.  If a match is found, a
541	 * related callback was received before the response to the original
542	 * call.
543	 */
544	if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
 
545		status = htonl(NFS4ERR_DELAY);
546		goto out_unlock;
547	}
548
549	/*
550	 * RFC5661 20.9.3
551	 * If CB_SEQUENCE returns an error, then the state of the slot
552	 * (sequence ID, cached reply) MUST NOT change.
553	 */
554	slot->seq_nr = args->csa_sequenceid;
555out_unlock:
556	spin_unlock(&tbl->slot_tbl_lock);
557
558out:
559	cps->clp = clp; /* put in nfs4_callback_compound */
560	for (i = 0; i < args->csa_nrclists; i++)
561		kfree(args->csa_rclists[i].rcl_refcalls);
562	kfree(args->csa_rclists);
563
564	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
565		cps->drc_status = status;
566		status = 0;
567	} else
568		res->csr_status = status;
569
570	trace_nfs4_cb_sequence(args, res, status);
571	return status;
572}
573
574static bool
575validate_bitmap_values(unsigned int mask)
576{
577	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
578}
579
580__be32 nfs4_callback_recallany(void *argp, void *resp,
581			       struct cb_process_state *cps)
582{
583	struct cb_recallanyargs *args = argp;
584	__be32 status;
585	fmode_t flags = 0;
 
586
587	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
588	if (!cps->clp) /* set in cb_sequence */
589		goto out;
590
591	dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
592		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
593
594	status = cpu_to_be32(NFS4ERR_INVAL);
595	if (!validate_bitmap_values(args->craa_type_mask))
596		goto out;
597
598	status = cpu_to_be32(NFS4_OK);
599	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
600		flags = FMODE_READ;
601	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
602		flags |= FMODE_WRITE;
603	if (flags)
604		nfs_expire_unused_delegation_types(cps->clp, flags);
605
606	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
607		pnfs_recall_all_layouts(cps->clp);
 
 
 
 
 
 
 
 
 
 
 
 
608out:
609	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
610	return status;
611}
612
613/* Reduce the fore channel's max_slots to the target value */
614__be32 nfs4_callback_recallslot(void *argp, void *resp,
615				struct cb_process_state *cps)
616{
617	struct cb_recallslotargs *args = argp;
618	struct nfs4_slot_table *fc_tbl;
619	__be32 status;
620
621	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
622	if (!cps->clp) /* set in cb_sequence */
623		goto out;
624
625	dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
626		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
627		args->crsa_target_highest_slotid);
628
629	fc_tbl = &cps->clp->cl_session->fc_slot_table;
630
631	status = htonl(NFS4_OK);
632
633	nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
634	nfs41_notify_server(cps->clp);
635out:
636	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
637	return status;
638}
639
640__be32 nfs4_callback_notify_lock(void *argp, void *resp,
641				 struct cb_process_state *cps)
642{
643	struct cb_notify_lock_args *args = argp;
644
645	if (!cps->clp) /* set in cb_sequence */
646		return htonl(NFS4ERR_OP_NOT_IN_SESSION);
647
648	dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
649		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
650
651	/* Don't wake anybody if the string looked bogus */
652	if (args->cbnl_valid)
653		__wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
654
655	return htonl(NFS4_OK);
656}
657#endif /* CONFIG_NFS_V4_1 */
v5.14.15
  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	res->bitmap[0] = res->bitmap[1] = 0;
 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	rcu_read_lock();
 55	delegation = nfs4_get_valid_delegation(inode);
 56	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
 57		goto out_iput;
 58	res->size = i_size_read(inode);
 59	res->change_attr = delegation->change_attr;
 60	if (nfs_have_writebacks(inode))
 61		res->change_attr++;
 62	res->ctime = inode->i_ctime;
 63	res->mtime = inode->i_mtime;
 64	res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
 65		args->bitmap[0];
 66	res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
 67		args->bitmap[1];
 68	res->status = 0;
 69out_iput:
 70	rcu_read_unlock();
 71	trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
 72	nfs_iput_and_deactive(inode);
 73out:
 74	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
 75	return res->status;
 76}
 77
 78__be32 nfs4_callback_recall(void *argp, void *resp,
 79			    struct cb_process_state *cps)
 80{
 81	struct cb_recallargs *args = argp;
 82	struct inode *inode;
 83	__be32 res;
 84	
 85	res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
 86	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
 87		goto out;
 88
 89	dprintk_rcu("NFS: RECALL callback request from %s\n",
 90		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 91
 92	res = htonl(NFS4ERR_BADHANDLE);
 93	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
 94	if (IS_ERR(inode)) {
 95		if (inode == ERR_PTR(-EAGAIN))
 96			res = htonl(NFS4ERR_DELAY);
 97		trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
 98				&args->stateid, -ntohl(res));
 99		goto out;
100	}
101	/* Set up a helper thread to actually return the delegation */
102	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
103	case 0:
104		res = 0;
105		break;
106	case -ENOENT:
107		res = htonl(NFS4ERR_BAD_STATEID);
108		break;
109	default:
110		res = htonl(NFS4ERR_RESOURCE);
111	}
112	trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
113			&args->stateid, -ntohl(res));
114	nfs_iput_and_deactive(inode);
115out:
116	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
117	return res;
118}
119
120#if defined(CONFIG_NFS_V4_1)
121
122/*
123 * Lookup a layout inode by stateid
124 *
125 * Note: returns a refcount on the inode and superblock
126 */
127static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
128		const nfs4_stateid *stateid)
129	__must_hold(RCU)
130{
131	struct nfs_server *server;
132	struct inode *inode;
133	struct pnfs_layout_hdr *lo;
134
135	rcu_read_lock();
136	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
137		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
138			if (!pnfs_layout_is_valid(lo))
 
139				continue;
140			if (!nfs4_stateid_match_other(stateid, &lo->plh_stateid))
 
141				continue;
142			if (nfs_sb_active(server->super))
143				inode = igrab(lo->plh_inode);
144			else
145				inode = ERR_PTR(-EAGAIN);
146			rcu_read_unlock();
147			if (inode)
148				return inode;
149			nfs_sb_deactive(server->super);
150			return ERR_PTR(-EAGAIN);
151		}
152	}
153	rcu_read_unlock();
154	return ERR_PTR(-ENOENT);
155}
156
157/*
158 * Lookup a layout inode by filehandle.
159 *
160 * Note: returns a refcount on the inode and superblock
161 *
162 */
163static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
164		const struct nfs_fh *fh)
165{
166	struct nfs_server *server;
167	struct nfs_inode *nfsi;
168	struct inode *inode;
169	struct pnfs_layout_hdr *lo;
170
171	rcu_read_lock();
172	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
173		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
174			nfsi = NFS_I(lo->plh_inode);
175			if (nfs_compare_fh(fh, &nfsi->fh))
176				continue;
177			if (nfsi->layout != lo)
178				continue;
179			if (nfs_sb_active(server->super))
180				inode = igrab(lo->plh_inode);
181			else
182				inode = ERR_PTR(-EAGAIN);
183			rcu_read_unlock();
184			if (inode)
185				return inode;
186			nfs_sb_deactive(server->super);
187			return ERR_PTR(-EAGAIN);
 
 
 
188		}
189	}
190	rcu_read_unlock();
191	return ERR_PTR(-ENOENT);
192}
193
194static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
195		const struct nfs_fh *fh,
196		const nfs4_stateid *stateid)
197{
198	struct inode *inode;
199
 
 
200	inode = nfs_layout_find_inode_by_stateid(clp, stateid);
201	if (inode == ERR_PTR(-ENOENT))
202		inode = nfs_layout_find_inode_by_fh(clp, fh);
 
 
 
203	return inode;
204}
205
206/*
207 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
208 */
209static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
210					const nfs4_stateid *new)
211{
212	u32 oldseq, newseq;
213
214	/* Is the stateid not initialised? */
215	if (!pnfs_layout_is_valid(lo))
216		return NFS4ERR_NOMATCHING_LAYOUT;
217
218	/* Mismatched stateid? */
219	if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
220		return NFS4ERR_BAD_STATEID;
221
222	newseq = be32_to_cpu(new->seqid);
223	/* Are we already in a layout recall situation? */
224	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
225	    lo->plh_return_seq != 0) {
226		if (newseq < lo->plh_return_seq)
227			return NFS4ERR_OLD_STATEID;
228		if (newseq > lo->plh_return_seq)
229			return NFS4ERR_DELAY;
230		goto out;
231	}
232
233	/* Check that the stateid matches what we think it should be. */
234	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
235	if (newseq > oldseq + 1)
236		return NFS4ERR_DELAY;
237	/* Crazy server! */
238	if (newseq <= oldseq)
239		return NFS4ERR_OLD_STATEID;
240out:
241	return NFS_OK;
242}
243
244static u32 initiate_file_draining(struct nfs_client *clp,
245				  struct cb_layoutrecallargs *args)
246{
247	struct inode *ino;
248	struct pnfs_layout_hdr *lo;
249	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
250	LIST_HEAD(free_me_list);
251
252	ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
253	if (IS_ERR(ino)) {
254		if (ino == ERR_PTR(-EAGAIN))
255			rv = NFS4ERR_DELAY;
256		goto out_noput;
257	}
258
259	pnfs_layoutcommit_inode(ino, false);
260
261
262	spin_lock(&ino->i_lock);
263	lo = NFS_I(ino)->layout;
264	if (!lo) {
265		spin_unlock(&ino->i_lock);
266		goto out;
267	}
268	pnfs_get_layout_hdr(lo);
269	rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid);
270	if (rv != NFS_OK)
271		goto unlock;
 
272
273	/*
274	 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
275	 */
276	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
277		rv = NFS4ERR_DELAY;
278		goto unlock;
279	}
280
281	pnfs_set_layout_stateid(lo, &args->cbl_stateid, NULL, true);
282	switch (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
283				&args->cbl_range,
284				be32_to_cpu(args->cbl_stateid.seqid))) {
285	case 0:
286	case -EBUSY:
287		/* There are layout segments that need to be returned */
288		rv = NFS4_OK;
289		break;
290	case -ENOENT:
291		/* Embrace your forgetfulness! */
292		rv = NFS4ERR_NOMATCHING_LAYOUT;
 
293
294		if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
295			NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
296				&args->cbl_range);
297		}
298	}
299unlock:
300	spin_unlock(&ino->i_lock);
301	pnfs_free_lseg_list(&free_me_list);
302	/* Free all lsegs that are attached to commit buckets */
303	nfs_commit_inode(ino, 0);
304	pnfs_put_layout_hdr(lo);
305out:
306	nfs_iput_and_deactive(ino);
307out_noput:
308	trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
309			&args->cbl_stateid, -rv);
 
310	return rv;
311}
312
313static u32 initiate_bulk_draining(struct nfs_client *clp,
314				  struct cb_layoutrecallargs *args)
315{
316	int stat;
317
318	if (args->cbl_recall_type == RETURN_FSID)
319		stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
320	else
321		stat = pnfs_destroy_layouts_byclid(clp, true);
322	if (stat != 0)
323		return NFS4ERR_DELAY;
324	return NFS4ERR_NOMATCHING_LAYOUT;
325}
326
327static u32 do_callback_layoutrecall(struct nfs_client *clp,
328				    struct cb_layoutrecallargs *args)
329{
330	if (args->cbl_recall_type == RETURN_FILE)
331		return initiate_file_draining(clp, args);
332	return initiate_bulk_draining(clp, args);
333}
334
335__be32 nfs4_callback_layoutrecall(void *argp, void *resp,
336				  struct cb_process_state *cps)
337{
338	struct cb_layoutrecallargs *args = argp;
339	u32 res = NFS4ERR_OP_NOT_IN_SESSION;
340
341	if (cps->clp)
342		res = do_callback_layoutrecall(cps->clp, args);
343	return cpu_to_be32(res);
344}
345
346static void pnfs_recall_all_layouts(struct nfs_client *clp)
347{
348	struct cb_layoutrecallargs args;
349
350	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
351	memset(&args, 0, sizeof(args));
352	args.cbl_recall_type = RETURN_ALL;
353	/* FIXME we ignore errors, what should we do? */
354	do_callback_layoutrecall(clp, &args);
355}
356
357__be32 nfs4_callback_devicenotify(void *argp, void *resp,
358				  struct cb_process_state *cps)
359{
360	struct cb_devicenotifyargs *args = argp;
361	int i;
362	__be32 res = 0;
363	struct nfs_client *clp = cps->clp;
364	struct nfs_server *server = NULL;
365
366	if (!clp) {
367		res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
368		goto out;
369	}
370
371	for (i = 0; i < args->ndevs; i++) {
372		struct cb_devicenotifyitem *dev = &args->devs[i];
373
374		if (!server ||
375		    server->pnfs_curr_ld->id != dev->cbd_layout_type) {
376			rcu_read_lock();
377			list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
378				if (server->pnfs_curr_ld &&
379				    server->pnfs_curr_ld->id == dev->cbd_layout_type) {
380					rcu_read_unlock();
381					goto found;
382				}
383			rcu_read_unlock();
384			continue;
385		}
386
387	found:
388		nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
389	}
390
391out:
392	kfree(args->devs);
393	return res;
394}
395
396/*
397 * Validate the sequenceID sent by the server.
398 * Return success if the sequenceID is one more than what we last saw on
399 * this slot, accounting for wraparound.  Increments the slot's sequence.
400 *
401 * We don't yet implement a duplicate request cache, instead we set the
402 * back channel ca_maxresponsesize_cached to zero. This is OK for now
403 * since we only currently implement idempotent callbacks anyway.
404 *
405 * We have a single slot backchannel at this time, so we don't bother
406 * checking the used_slots bit array on the table.  The lower layer guarantees
407 * a single outstanding callback request at a time.
408 */
409static __be32
410validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
411		const struct cb_sequenceargs * args)
412{
413	__be32 ret;
414
415	ret = cpu_to_be32(NFS4ERR_BADSLOT);
416	if (args->csa_slotid > tbl->server_highest_slotid)
417		goto out_err;
418
419	/* Replay */
420	if (args->csa_sequenceid == slot->seq_nr) {
421		ret = cpu_to_be32(NFS4ERR_DELAY);
422		if (nfs4_test_locked_slot(tbl, slot->slot_nr))
423			goto out_err;
424
425		/* Signal process_op to set this error on next op */
426		ret = cpu_to_be32(NFS4ERR_RETRY_UNCACHED_REP);
427		if (args->csa_cachethis == 0)
428			goto out_err;
429
430		/* Liar! We never allowed you to set csa_cachethis != 0 */
431		ret = cpu_to_be32(NFS4ERR_SEQ_FALSE_RETRY);
432		goto out_err;
433	}
434
435	/* Note: wraparound relies on seq_nr being of type u32 */
 
 
 
 
 
 
436	/* Misordered request */
437	ret = cpu_to_be32(NFS4ERR_SEQ_MISORDERED);
438	if (args->csa_sequenceid != slot->seq_nr + 1)
439		goto out_err;
440
441	return cpu_to_be32(NFS4_OK);
442
443out_err:
444	trace_nfs4_cb_seqid_err(args, ret);
445	return ret;
446}
447
448/*
449 * For each referring call triple, check the session's slot table for
450 * a match.  If the slot is in use and the sequence numbers match, the
451 * client is still waiting for a response to the original request.
452 */
453static int referring_call_exists(struct nfs_client *clp,
454				  uint32_t nrclists,
455				  struct referring_call_list *rclists,
456				  spinlock_t *lock)
457	__releases(lock)
458	__acquires(lock)
459{
460	int status = 0;
461	int i, j;
462	struct nfs4_session *session;
463	struct nfs4_slot_table *tbl;
464	struct referring_call_list *rclist;
465	struct referring_call *ref;
466
467	/*
468	 * XXX When client trunking is implemented, this becomes
469	 * a session lookup from within the loop
470	 */
471	session = clp->cl_session;
472	tbl = &session->fc_slot_table;
473
474	for (i = 0; i < nrclists; i++) {
475		rclist = &rclists[i];
476		if (memcmp(session->sess_id.data,
477			   rclist->rcl_sessionid.data,
478			   NFS4_MAX_SESSIONID_LEN) != 0)
479			continue;
480
481		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
482			ref = &rclist->rcl_refcalls[j];
483			spin_unlock(lock);
484			status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
485					ref->rc_sequenceid, HZ >> 1) < 0;
486			spin_lock(lock);
487			if (status)
488				goto out;
489		}
490	}
491
492out:
493	return status;
494}
495
496__be32 nfs4_callback_sequence(void *argp, void *resp,
497			      struct cb_process_state *cps)
498{
499	struct cb_sequenceargs *args = argp;
500	struct cb_sequenceres *res = resp;
501	struct nfs4_slot_table *tbl;
502	struct nfs4_slot *slot;
503	struct nfs_client *clp;
504	int i;
505	__be32 status = htonl(NFS4ERR_BADSESSION);
506
507	clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
508					 &args->csa_sessionid, cps->minorversion);
509	if (clp == NULL)
510		goto out;
511
512	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
513		goto out;
514
515	tbl = &clp->cl_session->bc_slot_table;
516
517	/* Set up res before grabbing the spinlock */
518	memcpy(&res->csr_sessionid, &args->csa_sessionid,
519	       sizeof(res->csr_sessionid));
520	res->csr_sequenceid = args->csa_sequenceid;
521	res->csr_slotid = args->csa_slotid;
522
523	spin_lock(&tbl->slot_tbl_lock);
524	/* state manager is resetting the session */
525	if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
526		status = htonl(NFS4ERR_DELAY);
527		/* Return NFS4ERR_BADSESSION if we're draining the session
528		 * in order to reset it.
529		 */
530		if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
531			status = htonl(NFS4ERR_BADSESSION);
532		goto out_unlock;
533	}
534
535	status = htonl(NFS4ERR_BADSLOT);
536	slot = nfs4_lookup_slot(tbl, args->csa_slotid);
537	if (IS_ERR(slot))
538		goto out_unlock;
539
540	res->csr_highestslotid = tbl->server_highest_slotid;
541	res->csr_target_highestslotid = tbl->target_highest_slotid;
542
543	status = validate_seqid(tbl, slot, args);
544	if (status)
545		goto out_unlock;
546	if (!nfs4_try_to_lock_slot(tbl, slot)) {
547		status = htonl(NFS4ERR_DELAY);
548		goto out_unlock;
549	}
550	cps->slot = slot;
551
552	/* The ca_maxresponsesize_cached is 0 with no DRC */
553	if (args->csa_cachethis != 0) {
554		status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
555		goto out_unlock;
556	}
557
558	/*
559	 * Check for pending referring calls.  If a match is found, a
560	 * related callback was received before the response to the original
561	 * call.
562	 */
563	if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
564				&tbl->slot_tbl_lock) < 0) {
565		status = htonl(NFS4ERR_DELAY);
566		goto out_unlock;
567	}
568
569	/*
570	 * RFC5661 20.9.3
571	 * If CB_SEQUENCE returns an error, then the state of the slot
572	 * (sequence ID, cached reply) MUST NOT change.
573	 */
574	slot->seq_nr = args->csa_sequenceid;
575out_unlock:
576	spin_unlock(&tbl->slot_tbl_lock);
577
578out:
579	cps->clp = clp; /* put in nfs4_callback_compound */
580	for (i = 0; i < args->csa_nrclists; i++)
581		kfree(args->csa_rclists[i].rcl_refcalls);
582	kfree(args->csa_rclists);
583
584	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
585		cps->drc_status = status;
586		status = 0;
587	} else
588		res->csr_status = status;
589
590	trace_nfs4_cb_sequence(args, res, status);
591	return status;
592}
593
594static bool
595validate_bitmap_values(unsigned int mask)
596{
597	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
598}
599
600__be32 nfs4_callback_recallany(void *argp, void *resp,
601			       struct cb_process_state *cps)
602{
603	struct cb_recallanyargs *args = argp;
604	__be32 status;
605	fmode_t flags = 0;
606	bool schedule_manager = false;
607
608	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
609	if (!cps->clp) /* set in cb_sequence */
610		goto out;
611
612	dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
613		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
614
615	status = cpu_to_be32(NFS4ERR_INVAL);
616	if (!validate_bitmap_values(args->craa_type_mask))
617		goto out;
618
619	status = cpu_to_be32(NFS4_OK);
620	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
621		flags = FMODE_READ;
622	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
623		flags |= FMODE_WRITE;
624	if (flags)
625		nfs_expire_unused_delegation_types(cps->clp, flags);
626
627	if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
628		pnfs_recall_all_layouts(cps->clp);
629
630	if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_READ)) {
631		set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &cps->clp->cl_state);
632		schedule_manager = true;
633	}
634	if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_RW)) {
635		set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &cps->clp->cl_state);
636		schedule_manager = true;
637	}
638	if (schedule_manager)
639		nfs4_schedule_state_manager(cps->clp);
640
641out:
642	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
643	return status;
644}
645
646/* Reduce the fore channel's max_slots to the target value */
647__be32 nfs4_callback_recallslot(void *argp, void *resp,
648				struct cb_process_state *cps)
649{
650	struct cb_recallslotargs *args = argp;
651	struct nfs4_slot_table *fc_tbl;
652	__be32 status;
653
654	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
655	if (!cps->clp) /* set in cb_sequence */
656		goto out;
657
658	dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
659		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
660		args->crsa_target_highest_slotid);
661
662	fc_tbl = &cps->clp->cl_session->fc_slot_table;
663
664	status = htonl(NFS4_OK);
665
666	nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
667	nfs41_notify_server(cps->clp);
668out:
669	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
670	return status;
671}
672
673__be32 nfs4_callback_notify_lock(void *argp, void *resp,
674				 struct cb_process_state *cps)
675{
676	struct cb_notify_lock_args *args = argp;
677
678	if (!cps->clp) /* set in cb_sequence */
679		return htonl(NFS4ERR_OP_NOT_IN_SESSION);
680
681	dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
682		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
683
684	/* Don't wake anybody if the string looked bogus */
685	if (args->cbnl_valid)
686		__wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
687
688	return htonl(NFS4_OK);
689}
690#endif /* CONFIG_NFS_V4_1 */
691#ifdef CONFIG_NFS_V4_2
692static void nfs4_copy_cb_args(struct nfs4_copy_state *cp_state,
693				struct cb_offloadargs *args)
694{
695	cp_state->count = args->wr_count;
696	cp_state->error = args->error;
697	if (!args->error) {
698		cp_state->verf.committed = args->wr_writeverf.committed;
699		memcpy(&cp_state->verf.verifier.data[0],
700			&args->wr_writeverf.verifier.data[0],
701			NFS4_VERIFIER_SIZE);
702	}
703}
704
705__be32 nfs4_callback_offload(void *data, void *dummy,
706			     struct cb_process_state *cps)
707{
708	struct cb_offloadargs *args = data;
709	struct nfs_server *server;
710	struct nfs4_copy_state *copy, *tmp_copy;
711	bool found = false;
712
713	copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_NOFS);
714	if (!copy)
715		return htonl(NFS4ERR_SERVERFAULT);
716
717	spin_lock(&cps->clp->cl_lock);
718	rcu_read_lock();
719	list_for_each_entry_rcu(server, &cps->clp->cl_superblocks,
720				client_link) {
721		list_for_each_entry(tmp_copy, &server->ss_copies, copies) {
722			if (memcmp(args->coa_stateid.other,
723					tmp_copy->stateid.other,
724					sizeof(args->coa_stateid.other)))
725				continue;
726			nfs4_copy_cb_args(tmp_copy, args);
727			complete(&tmp_copy->completion);
728			found = true;
729			goto out;
730		}
731	}
732out:
733	rcu_read_unlock();
734	if (!found) {
735		memcpy(&copy->stateid, &args->coa_stateid, NFS4_STATEID_SIZE);
736		nfs4_copy_cb_args(copy, args);
737		list_add_tail(&copy->copies, &cps->clp->pending_cb_stateids);
738	} else
739		kfree(copy);
740	spin_unlock(&cps->clp->cl_lock);
741
742	return 0;
743}
744#endif /* CONFIG_NFS_V4_2 */