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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 */
v4.6
 
  1/*
  2 * linux/fs/nfs/callback_proc.c
  3 *
  4 * Copyright (C) 2004 Trond Myklebust
  5 *
  6 * NFSv4 callback procedures
  7 */
  8#include <linux/nfs4.h>
  9#include <linux/nfs_fs.h>
 10#include <linux/slab.h>
 11#include <linux/rcupdate.h>
 12#include "nfs4_fs.h"
 13#include "callback.h"
 14#include "delegation.h"
 15#include "internal.h"
 16#include "pnfs.h"
 17#include "nfs4session.h"
 18#include "nfs4trace.h"
 19
 20#define NFSDBG_FACILITY NFSDBG_CALLBACK
 21
 22__be32 nfs4_callback_getattr(struct cb_getattrargs *args,
 23			     struct cb_getattrres *res,
 24			     struct cb_process_state *cps)
 25{
 
 
 26	struct nfs_delegation *delegation;
 27	struct nfs_inode *nfsi;
 28	struct inode *inode;
 29
 30	res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
 31	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
 32		goto out;
 33
 34	res->bitmap[0] = res->bitmap[1] = 0;
 35	res->status = htonl(NFS4ERR_BADHANDLE);
 36
 37	dprintk_rcu("NFS: GETATTR callback request from %s\n",
 38		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 39
 40	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
 41	if (inode == NULL) {
 42		trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
 43				-ntohl(res->status));
 44		goto out;
 45	}
 46	nfsi = NFS_I(inode);
 47	rcu_read_lock();
 48	delegation = rcu_dereference(nfsi->delegation);
 49	if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
 50		goto out_iput;
 51	res->size = i_size_read(inode);
 52	res->change_attr = delegation->change_attr;
 53	if (nfsi->nrequests != 0)
 54		res->change_attr++;
 55	res->ctime = inode->i_ctime;
 56	res->mtime = inode->i_mtime;
 57	res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
 58		args->bitmap[0];
 59	res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
 60		args->bitmap[1];
 61	res->status = 0;
 62out_iput:
 63	rcu_read_unlock();
 64	trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
 65	iput(inode);
 66out:
 67	dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
 68	return res->status;
 69}
 70
 71__be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
 72			    struct cb_process_state *cps)
 73{
 
 74	struct inode *inode;
 75	__be32 res;
 76	
 77	res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
 78	if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
 79		goto out;
 80
 81	dprintk_rcu("NFS: RECALL callback request from %s\n",
 82		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 83
 84	res = htonl(NFS4ERR_BADHANDLE);
 85	inode = nfs_delegation_find_inode(cps->clp, &args->fh);
 86	if (inode == NULL) {
 87		trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
 88				&args->stateid, -ntohl(res));
 89		goto out;
 90	}
 91	/* Set up a helper thread to actually return the delegation */
 92	switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
 93	case 0:
 94		res = 0;
 95		break;
 96	case -ENOENT:
 97		res = htonl(NFS4ERR_BAD_STATEID);
 98		break;
 99	default:
100		res = htonl(NFS4ERR_RESOURCE);
101	}
102	trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
103			&args->stateid, -ntohl(res));
104	iput(inode);
105out:
106	dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
107	return res;
108}
109
110#if defined(CONFIG_NFS_V4_1)
111
112/*
113 * Lookup a layout by filehandle.
114 *
115 * Note: gets a refcount on the layout hdr and on its respective inode.
116 * Caller must put the layout hdr and the inode.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
117 *
118 * TODO: keep track of all layouts (and delegations) in a hash table
119 * hashed by filehandle.
120 */
121static struct pnfs_layout_hdr * get_layout_by_fh_locked(struct nfs_client *clp,
122		struct nfs_fh *fh, nfs4_stateid *stateid)
123{
124	struct nfs_server *server;
125	struct inode *ino;
 
126	struct pnfs_layout_hdr *lo;
127
 
128	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
129		list_for_each_entry(lo, &server->layouts, plh_layouts) {
130			if (!nfs4_stateid_match_other(&lo->plh_stateid, stateid))
 
131				continue;
132			if (nfs_compare_fh(fh, &NFS_I(lo->plh_inode)->fh))
133				continue;
134			ino = igrab(lo->plh_inode);
135			if (!ino)
136				break;
137			spin_lock(&ino->i_lock);
138			/* Is this layout in the process of being freed? */
139			if (NFS_I(ino)->layout != lo) {
140				spin_unlock(&ino->i_lock);
141				iput(ino);
142				break;
 
143			}
144			pnfs_get_layout_hdr(lo);
145			spin_unlock(&ino->i_lock);
146			return lo;
147		}
148	}
149
150	return NULL;
151}
152
153static struct pnfs_layout_hdr * get_layout_by_fh(struct nfs_client *clp,
154		struct nfs_fh *fh, nfs4_stateid *stateid)
 
155{
156	struct pnfs_layout_hdr *lo;
157
158	spin_lock(&clp->cl_lock);
159	rcu_read_lock();
160	lo = get_layout_by_fh_locked(clp, fh, stateid);
 
 
161	rcu_read_unlock();
162	spin_unlock(&clp->cl_lock);
163
164	return lo;
165}
166
167/*
168 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
169 */
170static bool pnfs_check_stateid_sequence(struct pnfs_layout_hdr *lo,
171					const nfs4_stateid *new)
172{
173	u32 oldseq, newseq;
174
175	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 
 
 
 
 
 
 
176	newseq = be32_to_cpu(new->seqid);
 
 
 
 
 
 
 
 
 
177
 
 
178	if (newseq > oldseq + 1)
179		return false;
180	return true;
 
 
 
 
181}
182
183static u32 initiate_file_draining(struct nfs_client *clp,
184				  struct cb_layoutrecallargs *args)
185{
186	struct inode *ino;
187	struct pnfs_layout_hdr *lo;
188	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
189	LIST_HEAD(free_me_list);
190
191	lo = get_layout_by_fh(clp, &args->cbl_fh, &args->cbl_stateid);
192	if (!lo) {
193		trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, NULL,
194				&args->cbl_stateid, -rv);
195		goto out;
196	}
197
198	ino = lo->plh_inode;
 
199
200	spin_lock(&ino->i_lock);
201	if (!pnfs_check_stateid_sequence(lo, &args->cbl_stateid)) {
202		rv = NFS4ERR_DELAY;
 
 
 
 
 
 
203		goto unlock;
204	}
205	pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
206	spin_unlock(&ino->i_lock);
207
208	pnfs_layoutcommit_inode(ino, false);
209
210	spin_lock(&ino->i_lock);
211	/*
212	 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
213	 */
214	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
215		rv = NFS4ERR_DELAY;
216		goto unlock;
217	}
218
219	if (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
220					&args->cbl_range)) {
 
221		rv = NFS4_OK;
222		goto unlock;
223	}
224
 
 
 
225	if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
226		NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
227			&args->cbl_range);
228	}
229	pnfs_mark_layout_returned_if_empty(lo);
230unlock:
231	spin_unlock(&ino->i_lock);
232	pnfs_free_lseg_list(&free_me_list);
233	/* Free all lsegs that are attached to commit buckets */
234	nfs_commit_inode(ino, 0);
235	pnfs_put_layout_hdr(lo);
 
236	trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
237			&args->cbl_stateid, -rv);
238	iput(ino);
239out:
240	return rv;
241}
242
243static u32 initiate_bulk_draining(struct nfs_client *clp,
244				  struct cb_layoutrecallargs *args)
245{
246	int stat;
247
248	if (args->cbl_recall_type == RETURN_FSID)
249		stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
250	else
251		stat = pnfs_destroy_layouts_byclid(clp, true);
252	if (stat != 0)
253		return NFS4ERR_DELAY;
254	return NFS4ERR_NOMATCHING_LAYOUT;
255}
256
257static u32 do_callback_layoutrecall(struct nfs_client *clp,
258				    struct cb_layoutrecallargs *args)
259{
260	u32 res;
261
262	dprintk("%s enter, type=%i\n", __func__, args->cbl_recall_type);
263	if (args->cbl_recall_type == RETURN_FILE)
264		res = initiate_file_draining(clp, args);
265	else
266		res = initiate_bulk_draining(clp, args);
267	dprintk("%s returning %i\n", __func__, res);
268	return res;
269
270}
271
272__be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args,
273				  void *dummy, struct cb_process_state *cps)
274{
275	u32 res;
276
277	dprintk("%s: -->\n", __func__);
278
279	if (cps->clp)
280		res = do_callback_layoutrecall(cps->clp, args);
281	else
282		res = NFS4ERR_OP_NOT_IN_SESSION;
283
284	dprintk("%s: exit with status = %d\n", __func__, res);
285	return cpu_to_be32(res);
286}
287
288static void pnfs_recall_all_layouts(struct nfs_client *clp)
289{
290	struct cb_layoutrecallargs args;
291
292	/* Pretend we got a CB_LAYOUTRECALL(ALL) */
293	memset(&args, 0, sizeof(args));
294	args.cbl_recall_type = RETURN_ALL;
295	/* FIXME we ignore errors, what should we do? */
296	do_callback_layoutrecall(clp, &args);
297}
298
299__be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args,
300				  void *dummy, struct cb_process_state *cps)
301{
 
302	int i;
303	__be32 res = 0;
304	struct nfs_client *clp = cps->clp;
305	struct nfs_server *server = NULL;
306
307	dprintk("%s: -->\n", __func__);
308
309	if (!clp) {
310		res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
311		goto out;
312	}
313
314	for (i = 0; i < args->ndevs; i++) {
315		struct cb_devicenotifyitem *dev = &args->devs[i];
316
317		if (!server ||
318		    server->pnfs_curr_ld->id != dev->cbd_layout_type) {
319			rcu_read_lock();
320			list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
321				if (server->pnfs_curr_ld &&
322				    server->pnfs_curr_ld->id == dev->cbd_layout_type) {
323					rcu_read_unlock();
324					goto found;
325				}
326			rcu_read_unlock();
327			dprintk("%s: layout type %u not found\n",
328				__func__, dev->cbd_layout_type);
329			continue;
330		}
331
332	found:
333		nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
334	}
335
336out:
337	kfree(args->devs);
338	dprintk("%s: exit with status = %u\n",
339		__func__, be32_to_cpu(res));
340	return res;
341}
342
343/*
344 * Validate the sequenceID sent by the server.
345 * Return success if the sequenceID is one more than what we last saw on
346 * this slot, accounting for wraparound.  Increments the slot's sequence.
347 *
348 * We don't yet implement a duplicate request cache, instead we set the
349 * back channel ca_maxresponsesize_cached to zero. This is OK for now
350 * since we only currently implement idempotent callbacks anyway.
351 *
352 * We have a single slot backchannel at this time, so we don't bother
353 * checking the used_slots bit array on the table.  The lower layer guarantees
354 * a single outstanding callback request at a time.
355 */
356static __be32
357validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
358		const struct cb_sequenceargs * args)
359{
360	dprintk("%s enter. slotid %u seqid %u, slot table seqid: %u\n",
361		__func__, args->csa_slotid, args->csa_sequenceid, slot->seq_nr);
362
363	if (args->csa_slotid > tbl->server_highest_slotid)
364		return htonl(NFS4ERR_BADSLOT);
365
366	/* Replay */
367	if (args->csa_sequenceid == slot->seq_nr) {
368		dprintk("%s seqid %u is a replay\n",
369			__func__, args->csa_sequenceid);
370		if (nfs4_test_locked_slot(tbl, slot->slot_nr))
371			return htonl(NFS4ERR_DELAY);
372		/* Signal process_op to set this error on next op */
373		if (args->csa_cachethis == 0)
374			return htonl(NFS4ERR_RETRY_UNCACHED_REP);
375
376		/* Liar! We never allowed you to set csa_cachethis != 0 */
377		return htonl(NFS4ERR_SEQ_FALSE_RETRY);
378	}
379
380	/* Wraparound */
381	if (unlikely(slot->seq_nr == 0xFFFFFFFFU)) {
382		if (args->csa_sequenceid == 1)
383			return htonl(NFS4_OK);
384	} else if (likely(args->csa_sequenceid == slot->seq_nr + 1))
385		return htonl(NFS4_OK);
386
387	/* Misordered request */
388	return htonl(NFS4ERR_SEQ_MISORDERED);
389}
390
391/*
392 * For each referring call triple, check the session's slot table for
393 * a match.  If the slot is in use and the sequence numbers match, the
394 * client is still waiting for a response to the original request.
395 */
396static bool referring_call_exists(struct nfs_client *clp,
397				  uint32_t nrclists,
398				  struct referring_call_list *rclists)
399{
400	bool status = 0;
401	int i, j;
402	struct nfs4_session *session;
403	struct nfs4_slot_table *tbl;
404	struct referring_call_list *rclist;
405	struct referring_call *ref;
406
407	/*
408	 * XXX When client trunking is implemented, this becomes
409	 * a session lookup from within the loop
410	 */
411	session = clp->cl_session;
412	tbl = &session->fc_slot_table;
413
414	for (i = 0; i < nrclists; i++) {
415		rclist = &rclists[i];
416		if (memcmp(session->sess_id.data,
417			   rclist->rcl_sessionid.data,
418			   NFS4_MAX_SESSIONID_LEN) != 0)
419			continue;
420
421		for (j = 0; j < rclist->rcl_nrefcalls; j++) {
422			ref = &rclist->rcl_refcalls[j];
423
424			dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
425				"slotid %u\n", __func__,
426				((u32 *)&rclist->rcl_sessionid.data)[0],
427				((u32 *)&rclist->rcl_sessionid.data)[1],
428				((u32 *)&rclist->rcl_sessionid.data)[2],
429				((u32 *)&rclist->rcl_sessionid.data)[3],
430				ref->rc_sequenceid, ref->rc_slotid);
431
432			spin_lock(&tbl->slot_tbl_lock);
433			status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
434				  tbl->slots[ref->rc_slotid].seq_nr ==
435					ref->rc_sequenceid);
436			spin_unlock(&tbl->slot_tbl_lock);
437			if (status)
438				goto out;
439		}
440	}
441
442out:
443	return status;
444}
445
446__be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
447			      struct cb_sequenceres *res,
448			      struct cb_process_state *cps)
449{
 
 
450	struct nfs4_slot_table *tbl;
451	struct nfs4_slot *slot;
452	struct nfs_client *clp;
453	int i;
454	__be32 status = htonl(NFS4ERR_BADSESSION);
455
456	clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
457					 &args->csa_sessionid, cps->minorversion);
458	if (clp == NULL)
459		goto out;
460
461	if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
462		goto out;
463
464	tbl = &clp->cl_session->bc_slot_table;
465	slot = tbl->slots + args->csa_slotid;
466
467	/* Set up res before grabbing the spinlock */
468	memcpy(&res->csr_sessionid, &args->csa_sessionid,
469	       sizeof(res->csr_sessionid));
470	res->csr_sequenceid = args->csa_sequenceid;
471	res->csr_slotid = args->csa_slotid;
472
473	spin_lock(&tbl->slot_tbl_lock);
474	/* state manager is resetting the session */
475	if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
476		status = htonl(NFS4ERR_DELAY);
477		/* Return NFS4ERR_BADSESSION if we're draining the session
478		 * in order to reset it.
479		 */
480		if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
481			status = htonl(NFS4ERR_BADSESSION);
482		goto out_unlock;
483	}
484
485	status = htonl(NFS4ERR_BADSLOT);
486	slot = nfs4_lookup_slot(tbl, args->csa_slotid);
487	if (IS_ERR(slot))
488		goto out_unlock;
489
490	res->csr_highestslotid = tbl->server_highest_slotid;
491	res->csr_target_highestslotid = tbl->target_highest_slotid;
492
493	status = validate_seqid(tbl, slot, args);
494	if (status)
495		goto out_unlock;
496	if (!nfs4_try_to_lock_slot(tbl, slot)) {
497		status = htonl(NFS4ERR_DELAY);
498		goto out_unlock;
499	}
500	cps->slot = slot;
501
502	/* The ca_maxresponsesize_cached is 0 with no DRC */
503	if (args->csa_cachethis != 0)
504		return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
 
 
505
506	/*
507	 * Check for pending referring calls.  If a match is found, a
508	 * related callback was received before the response to the original
509	 * call.
510	 */
511	if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
512		status = htonl(NFS4ERR_DELAY);
513		goto out_unlock;
514	}
515
516	/*
517	 * RFC5661 20.9.3
518	 * If CB_SEQUENCE returns an error, then the state of the slot
519	 * (sequence ID, cached reply) MUST NOT change.
520	 */
521	slot->seq_nr = args->csa_sequenceid;
522out_unlock:
523	spin_unlock(&tbl->slot_tbl_lock);
524
525out:
526	cps->clp = clp; /* put in nfs4_callback_compound */
527	for (i = 0; i < args->csa_nrclists; i++)
528		kfree(args->csa_rclists[i].rcl_refcalls);
529	kfree(args->csa_rclists);
530
531	if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
532		cps->drc_status = status;
533		status = 0;
534	} else
535		res->csr_status = status;
536
537	trace_nfs4_cb_sequence(args, res, status);
538	dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
539		ntohl(status), ntohl(res->csr_status));
540	return status;
541}
542
543static bool
544validate_bitmap_values(unsigned long mask)
545{
546	return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
547}
548
549__be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy,
550			       struct cb_process_state *cps)
551{
 
552	__be32 status;
553	fmode_t flags = 0;
554
555	status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
556	if (!cps->clp) /* set in cb_sequence */
557		goto out;
558
559	dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
560		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
561
562	status = cpu_to_be32(NFS4ERR_INVAL);
563	if (!validate_bitmap_values(args->craa_type_mask))
564		goto out;
565
566	status = cpu_to_be32(NFS4_OK);
567	if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
568		     &args->craa_type_mask))
569		flags = FMODE_READ;
570	if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
571		     &args->craa_type_mask))
572		flags |= FMODE_WRITE;
573	if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *)
574		     &args->craa_type_mask))
575		pnfs_recall_all_layouts(cps->clp);
576	if (flags)
577		nfs_expire_unused_delegation_types(cps->clp, flags);
 
 
 
578out:
579	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
580	return status;
581}
582
583/* Reduce the fore channel's max_slots to the target value */
584__be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy,
585				struct cb_process_state *cps)
586{
 
587	struct nfs4_slot_table *fc_tbl;
588	__be32 status;
589
590	status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
591	if (!cps->clp) /* set in cb_sequence */
592		goto out;
593
594	dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
595		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
596		args->crsa_target_highest_slotid);
597
598	fc_tbl = &cps->clp->cl_session->fc_slot_table;
599
600	status = htonl(NFS4_OK);
601
602	nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
603	nfs41_notify_server(cps->clp);
604out:
605	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
606	return status;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
607}
608#endif /* CONFIG_NFS_V4_1 */