1// SPDX-License-Identifier: GPL-2.0
2#include <linux/ceph/ceph_debug.h>
3
4#include <linux/module.h>
5#include <linux/types.h>
6#include <linux/slab.h>
7#include <linux/random.h>
8#include <linux/sched.h>
9
10#include <linux/ceph/ceph_features.h>
11#include <linux/ceph/mon_client.h>
12#include <linux/ceph/libceph.h>
13#include <linux/ceph/debugfs.h>
14#include <linux/ceph/decode.h>
15#include <linux/ceph/auth.h>
16
17/*
18 * Interact with Ceph monitor cluster.  Handle requests for new map
19 * versions, and periodically resend as needed.  Also implement
20 * statfs() and umount().
21 *
22 * A small cluster of Ceph "monitors" are responsible for managing critical
23 * cluster configuration and state information.  An odd number (e.g., 3, 5)
24 * of cmon daemons use a modified version of the Paxos part-time parliament
25 * algorithm to manage the MDS map (mds cluster membership), OSD map, and
26 * list of clients who have mounted the file system.
27 *
28 * We maintain an open, active session with a monitor at all times in order to
29 * receive timely MDSMap updates.  We periodically send a keepalive byte on the
30 * TCP socket to ensure we detect a failure.  If the connection does break, we
31 * randomly hunt for a new monitor.  Once the connection is reestablished, we
32 * resend any outstanding requests.
33 */
34
35static const struct ceph_connection_operations mon_con_ops;
36
37static int __validate_auth(struct ceph_mon_client *monc);
38
39static int decode_mon_info(void **p, void *end, bool msgr2,
40			   struct ceph_entity_addr *addr)
41{
42	void *mon_info_end;
43	u32 struct_len;
44	u8 struct_v;
45	int ret;
46
47	ret = ceph_start_decoding(p, end, 1, "mon_info_t", &struct_v,
48				  &struct_len);
49	if (ret)
50		return ret;
51
52	mon_info_end = *p + struct_len;
53	ceph_decode_skip_string(p, end, e_inval);  /* skip mon name */
54	ret = ceph_decode_entity_addrvec(p, end, msgr2, addr);
55	if (ret)
56		return ret;
57
58	*p = mon_info_end;
59	return 0;
60
61e_inval:
62	return -EINVAL;
63}
64
65/*
66 * Decode a monmap blob (e.g., during mount).
67 *
68 * Assume MonMap v3 (i.e. encoding with MONNAMES and MONENC).
69 */
70static struct ceph_monmap *ceph_monmap_decode(void **p, void *end, bool msgr2)
71{
72	struct ceph_monmap *monmap = NULL;
73	struct ceph_fsid fsid;
74	u32 struct_len;
75	int blob_len;
76	int num_mon;
77	u8 struct_v;
78	u32 epoch;
79	int ret;
80	int i;
81
82	ceph_decode_32_safe(p, end, blob_len, e_inval);
83	ceph_decode_need(p, end, blob_len, e_inval);
84
85	ret = ceph_start_decoding(p, end, 6, "monmap", &struct_v, &struct_len);
86	if (ret)
87		goto fail;
88
89	dout("%s struct_v %d\n", __func__, struct_v);
90	ceph_decode_copy_safe(p, end, &fsid, sizeof(fsid), e_inval);
91	ceph_decode_32_safe(p, end, epoch, e_inval);
92	if (struct_v >= 6) {
93		u32 feat_struct_len;
94		u8 feat_struct_v;
95
96		*p += sizeof(struct ceph_timespec);  /* skip last_changed */
97		*p += sizeof(struct ceph_timespec);  /* skip created */
98
99		ret = ceph_start_decoding(p, end, 1, "mon_feature_t",
100					  &feat_struct_v, &feat_struct_len);
101		if (ret)
102			goto fail;
103
104		*p += feat_struct_len;  /* skip persistent_features */
105
106		ret = ceph_start_decoding(p, end, 1, "mon_feature_t",
107					  &feat_struct_v, &feat_struct_len);
108		if (ret)
109			goto fail;
110
111		*p += feat_struct_len;  /* skip optional_features */
112	}
113	ceph_decode_32_safe(p, end, num_mon, e_inval);
114
115	dout("%s fsid %pU epoch %u num_mon %d\n", __func__, &fsid, epoch,
116	     num_mon);
117	if (num_mon > CEPH_MAX_MON)
118		goto e_inval;
119
120	monmap = kmalloc(struct_size(monmap, mon_inst, num_mon), GFP_NOIO);
121	if (!monmap) {
122		ret = -ENOMEM;
123		goto fail;
124	}
125	monmap->fsid = fsid;
126	monmap->epoch = epoch;
127	monmap->num_mon = num_mon;
128
129	/* legacy_mon_addr map or mon_info map */
130	for (i = 0; i < num_mon; i++) {
131		struct ceph_entity_inst *inst = &monmap->mon_inst[i];
132
133		ceph_decode_skip_string(p, end, e_inval);  /* skip mon name */
134		inst->name.type = CEPH_ENTITY_TYPE_MON;
135		inst->name.num = cpu_to_le64(i);
136
137		if (struct_v >= 6)
138			ret = decode_mon_info(p, end, msgr2, &inst->addr);
139		else
140			ret = ceph_decode_entity_addr(p, end, &inst->addr);
141		if (ret)
142			goto fail;
143
144		dout("%s mon%d addr %s\n", __func__, i,
145		     ceph_pr_addr(&inst->addr));
146	}
147
148	return monmap;
149
150e_inval:
151	ret = -EINVAL;
152fail:
153	kfree(monmap);
154	return ERR_PTR(ret);
155}
156
157/*
158 * return true if *addr is included in the monmap.
159 */
160int ceph_monmap_contains(struct ceph_monmap *m, struct ceph_entity_addr *addr)
161{
162	int i;
163
164	for (i = 0; i < m->num_mon; i++) {
165		if (ceph_addr_equal_no_type(addr, &m->mon_inst[i].addr))
166			return 1;
167	}
168
169	return 0;
170}
171
172/*
173 * Send an auth request.
174 */
175static void __send_prepared_auth_request(struct ceph_mon_client *monc, int len)
176{
177	monc->pending_auth = 1;
178	monc->m_auth->front.iov_len = len;
179	monc->m_auth->hdr.front_len = cpu_to_le32(len);
180	ceph_msg_revoke(monc->m_auth);
181	ceph_msg_get(monc->m_auth);  /* keep our ref */
182	ceph_con_send(&monc->con, monc->m_auth);
183}
184
185/*
186 * Close monitor session, if any.
187 */
188static void __close_session(struct ceph_mon_client *monc)
189{
190	dout("__close_session closing mon%d\n", monc->cur_mon);
191	ceph_msg_revoke(monc->m_auth);
192	ceph_msg_revoke_incoming(monc->m_auth_reply);
193	ceph_msg_revoke(monc->m_subscribe);
194	ceph_msg_revoke_incoming(monc->m_subscribe_ack);
195	ceph_con_close(&monc->con);
196
197	monc->pending_auth = 0;
198	ceph_auth_reset(monc->auth);
199}
200
201/*
202 * Pick a new monitor at random and set cur_mon.  If we are repicking
203 * (i.e. cur_mon is already set), be sure to pick a different one.
204 */
205static void pick_new_mon(struct ceph_mon_client *monc)
206{
207	int old_mon = monc->cur_mon;
208
209	BUG_ON(monc->monmap->num_mon < 1);
210
211	if (monc->monmap->num_mon == 1) {
212		monc->cur_mon = 0;
213	} else {
214		int max = monc->monmap->num_mon;
215		int o = -1;
216		int n;
217
218		if (monc->cur_mon >= 0) {
219			if (monc->cur_mon < monc->monmap->num_mon)
220				o = monc->cur_mon;
221			if (o >= 0)
222				max--;
223		}
224
225		n = get_random_u32_below(max);
226		if (o >= 0 && n >= o)
227			n++;
228
229		monc->cur_mon = n;
230	}
231
232	dout("%s mon%d -> mon%d out of %d mons\n", __func__, old_mon,
233	     monc->cur_mon, monc->monmap->num_mon);
234}
235
236/*
237 * Open a session with a new monitor.
238 */
239static void __open_session(struct ceph_mon_client *monc)
240{
241	int ret;
242
243	pick_new_mon(monc);
244
245	monc->hunting = true;
246	if (monc->had_a_connection) {
247		monc->hunt_mult *= CEPH_MONC_HUNT_BACKOFF;
248		if (monc->hunt_mult > CEPH_MONC_HUNT_MAX_MULT)
249			monc->hunt_mult = CEPH_MONC_HUNT_MAX_MULT;
250	}
251
252	monc->sub_renew_after = jiffies; /* i.e., expired */
253	monc->sub_renew_sent = 0;
254
255	dout("%s opening mon%d\n", __func__, monc->cur_mon);
256	ceph_con_open(&monc->con, CEPH_ENTITY_TYPE_MON, monc->cur_mon,
257		      &monc->monmap->mon_inst[monc->cur_mon].addr);
258
259	/*
260	 * Queue a keepalive to ensure that in case of an early fault
261	 * the messenger doesn't put us into STANDBY state and instead
262	 * retries.  This also ensures that our timestamp is valid by
263	 * the time we finish hunting and delayed_work() checks it.
264	 */
265	ceph_con_keepalive(&monc->con);
266	if (ceph_msgr2(monc->client)) {
267		monc->pending_auth = 1;
268		return;
269	}
270
271	/* initiate authentication handshake */
272	ret = ceph_auth_build_hello(monc->auth,
273				    monc->m_auth->front.iov_base,
274				    monc->m_auth->front_alloc_len);
275	BUG_ON(ret <= 0);
276	__send_prepared_auth_request(monc, ret);
277}
278
279static void reopen_session(struct ceph_mon_client *monc)
280{
281	if (!monc->hunting)
282		pr_info("mon%d %s session lost, hunting for new mon\n",
283		    monc->cur_mon, ceph_pr_addr(&monc->con.peer_addr));
284
285	__close_session(monc);
286	__open_session(monc);
287}
288
289void ceph_monc_reopen_session(struct ceph_mon_client *monc)
290{
291	mutex_lock(&monc->mutex);
292	reopen_session(monc);
293	mutex_unlock(&monc->mutex);
294}
295
296static void un_backoff(struct ceph_mon_client *monc)
297{
298	monc->hunt_mult /= 2; /* reduce by 50% */
299	if (monc->hunt_mult < 1)
300		monc->hunt_mult = 1;
301	dout("%s hunt_mult now %d\n", __func__, monc->hunt_mult);
302}
303
304/*
305 * Reschedule delayed work timer.
306 */
307static void __schedule_delayed(struct ceph_mon_client *monc)
308{
309	unsigned long delay;
310
311	if (monc->hunting)
312		delay = CEPH_MONC_HUNT_INTERVAL * monc->hunt_mult;
313	else
314		delay = CEPH_MONC_PING_INTERVAL;
315
316	dout("__schedule_delayed after %lu\n", delay);
317	mod_delayed_work(system_wq, &monc->delayed_work,
318			 round_jiffies_relative(delay));
319}
320
321const char *ceph_sub_str[] = {
322	[CEPH_SUB_MONMAP] = "monmap",
323	[CEPH_SUB_OSDMAP] = "osdmap",
324	[CEPH_SUB_FSMAP]  = "fsmap.user",
325	[CEPH_SUB_MDSMAP] = "mdsmap",
326};
327
328/*
329 * Send subscribe request for one or more maps, according to
330 * monc->subs.
331 */
332static void __send_subscribe(struct ceph_mon_client *monc)
333{
334	struct ceph_msg *msg = monc->m_subscribe;
335	void *p = msg->front.iov_base;
336	void *const end = p + msg->front_alloc_len;
337	int num = 0;
338	int i;
339
340	dout("%s sent %lu\n", __func__, monc->sub_renew_sent);
341
342	BUG_ON(monc->cur_mon < 0);
343
344	if (!monc->sub_renew_sent)
345		monc->sub_renew_sent = jiffies | 1; /* never 0 */
346
347	msg->hdr.version = cpu_to_le16(2);
348
349	for (i = 0; i < ARRAY_SIZE(monc->subs); i++) {
350		if (monc->subs[i].want)
351			num++;
352	}
353	BUG_ON(num < 1); /* monmap sub is always there */
354	ceph_encode_32(&p, num);
355	for (i = 0; i < ARRAY_SIZE(monc->subs); i++) {
356		char buf[32];
357		int len;
358
359		if (!monc->subs[i].want)
360			continue;
361
362		len = sprintf(buf, "%s", ceph_sub_str[i]);
363		if (i == CEPH_SUB_MDSMAP &&
364		    monc->fs_cluster_id != CEPH_FS_CLUSTER_ID_NONE)
365			len += sprintf(buf + len, ".%d", monc->fs_cluster_id);
366
367		dout("%s %s start %llu flags 0x%x\n", __func__, buf,
368		     le64_to_cpu(monc->subs[i].item.start),
369		     monc->subs[i].item.flags);
370		ceph_encode_string(&p, end, buf, len);
371		memcpy(p, &monc->subs[i].item, sizeof(monc->subs[i].item));
372		p += sizeof(monc->subs[i].item);
373	}
374
375	BUG_ON(p > end);
376	msg->front.iov_len = p - msg->front.iov_base;
377	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
378	ceph_msg_revoke(msg);
379	ceph_con_send(&monc->con, ceph_msg_get(msg));
380}
381
382static void handle_subscribe_ack(struct ceph_mon_client *monc,
383				 struct ceph_msg *msg)
384{
385	unsigned int seconds;
386	struct ceph_mon_subscribe_ack *h = msg->front.iov_base;
387
388	if (msg->front.iov_len < sizeof(*h))
389		goto bad;
390	seconds = le32_to_cpu(h->duration);
391
392	mutex_lock(&monc->mutex);
393	if (monc->sub_renew_sent) {
394		/*
395		 * This is only needed for legacy (infernalis or older)
396		 * MONs -- see delayed_work().
397		 */
398		monc->sub_renew_after = monc->sub_renew_sent +
399					    (seconds >> 1) * HZ - 1;
400		dout("%s sent %lu duration %d renew after %lu\n", __func__,
401		     monc->sub_renew_sent, seconds, monc->sub_renew_after);
402		monc->sub_renew_sent = 0;
403	} else {
404		dout("%s sent %lu renew after %lu, ignoring\n", __func__,
405		     monc->sub_renew_sent, monc->sub_renew_after);
406	}
407	mutex_unlock(&monc->mutex);
408	return;
409bad:
410	pr_err("got corrupt subscribe-ack msg\n");
411	ceph_msg_dump(msg);
412}
413
414/*
415 * Register interest in a map
416 *
417 * @sub: one of CEPH_SUB_*
418 * @epoch: X for "every map since X", or 0 for "just the latest"
419 */
420static bool __ceph_monc_want_map(struct ceph_mon_client *monc, int sub,
421				 u32 epoch, bool continuous)
422{
423	__le64 start = cpu_to_le64(epoch);
424	u8 flags = !continuous ? CEPH_SUBSCRIBE_ONETIME : 0;
425
426	dout("%s %s epoch %u continuous %d\n", __func__, ceph_sub_str[sub],
427	     epoch, continuous);
428
429	if (monc->subs[sub].want &&
430	    monc->subs[sub].item.start == start &&
431	    monc->subs[sub].item.flags == flags)
432		return false;
433
434	monc->subs[sub].item.start = start;
435	monc->subs[sub].item.flags = flags;
436	monc->subs[sub].want = true;
437
438	return true;
439}
440
441bool ceph_monc_want_map(struct ceph_mon_client *monc, int sub, u32 epoch,
442			bool continuous)
443{
444	bool need_request;
445
446	mutex_lock(&monc->mutex);
447	need_request = __ceph_monc_want_map(monc, sub, epoch, continuous);
448	mutex_unlock(&monc->mutex);
449
450	return need_request;
451}
452EXPORT_SYMBOL(ceph_monc_want_map);
453
454/*
455 * Keep track of which maps we have
456 *
457 * @sub: one of CEPH_SUB_*
458 */
459static void __ceph_monc_got_map(struct ceph_mon_client *monc, int sub,
460				u32 epoch)
461{
462	dout("%s %s epoch %u\n", __func__, ceph_sub_str[sub], epoch);
463
464	if (monc->subs[sub].want) {
465		if (monc->subs[sub].item.flags & CEPH_SUBSCRIBE_ONETIME)
466			monc->subs[sub].want = false;
467		else
468			monc->subs[sub].item.start = cpu_to_le64(epoch + 1);
469	}
470
471	monc->subs[sub].have = epoch;
472}
473
474void ceph_monc_got_map(struct ceph_mon_client *monc, int sub, u32 epoch)
475{
476	mutex_lock(&monc->mutex);
477	__ceph_monc_got_map(monc, sub, epoch);
478	mutex_unlock(&monc->mutex);
479}
480EXPORT_SYMBOL(ceph_monc_got_map);
481
482void ceph_monc_renew_subs(struct ceph_mon_client *monc)
483{
484	mutex_lock(&monc->mutex);
485	__send_subscribe(monc);
486	mutex_unlock(&monc->mutex);
487}
488EXPORT_SYMBOL(ceph_monc_renew_subs);
489
490/*
491 * Wait for an osdmap with a given epoch.
492 *
493 * @epoch: epoch to wait for
494 * @timeout: in jiffies, 0 means "wait forever"
495 */
496int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
497			  unsigned long timeout)
498{
499	unsigned long started = jiffies;
500	long ret;
501
502	mutex_lock(&monc->mutex);
503	while (monc->subs[CEPH_SUB_OSDMAP].have < epoch) {
504		mutex_unlock(&monc->mutex);
505
506		if (timeout && time_after_eq(jiffies, started + timeout))
507			return -ETIMEDOUT;
508
509		ret = wait_event_interruptible_timeout(monc->client->auth_wq,
510				     monc->subs[CEPH_SUB_OSDMAP].have >= epoch,
511				     ceph_timeout_jiffies(timeout));
512		if (ret < 0)
513			return ret;
514
515		mutex_lock(&monc->mutex);
516	}
517
518	mutex_unlock(&monc->mutex);
519	return 0;
520}
521EXPORT_SYMBOL(ceph_monc_wait_osdmap);
522
523/*
524 * Open a session with a random monitor.  Request monmap and osdmap,
525 * which are waited upon in __ceph_open_session().
526 */
527int ceph_monc_open_session(struct ceph_mon_client *monc)
528{
529	mutex_lock(&monc->mutex);
530	__ceph_monc_want_map(monc, CEPH_SUB_MONMAP, 0, true);
531	__ceph_monc_want_map(monc, CEPH_SUB_OSDMAP, 0, false);
532	__open_session(monc);
533	__schedule_delayed(monc);
534	mutex_unlock(&monc->mutex);
535	return 0;
536}
537EXPORT_SYMBOL(ceph_monc_open_session);
538
539static void ceph_monc_handle_map(struct ceph_mon_client *monc,
540				 struct ceph_msg *msg)
541{
542	struct ceph_client *client = monc->client;
543	struct ceph_monmap *monmap;
544	void *p, *end;
545
546	mutex_lock(&monc->mutex);
547
548	dout("handle_monmap\n");
549	p = msg->front.iov_base;
550	end = p + msg->front.iov_len;
551
552	monmap = ceph_monmap_decode(&p, end, ceph_msgr2(client));
553	if (IS_ERR(monmap)) {
554		pr_err("problem decoding monmap, %d\n",
555		       (int)PTR_ERR(monmap));
556		ceph_msg_dump(msg);
557		goto out;
558	}
559
560	if (ceph_check_fsid(client, &monmap->fsid) < 0) {
561		kfree(monmap);
562		goto out;
563	}
564
565	kfree(monc->monmap);
566	monc->monmap = monmap;
567
568	__ceph_monc_got_map(monc, CEPH_SUB_MONMAP, monc->monmap->epoch);
569	client->have_fsid = true;
570
571out:
572	mutex_unlock(&monc->mutex);
573	wake_up_all(&client->auth_wq);
574}
575
576/*
577 * generic requests (currently statfs, mon_get_version)
578 */
579DEFINE_RB_FUNCS(generic_request, struct ceph_mon_generic_request, tid, node)
580
581static void release_generic_request(struct kref *kref)
582{
583	struct ceph_mon_generic_request *req =
584		container_of(kref, struct ceph_mon_generic_request, kref);
585
586	dout("%s greq %p request %p reply %p\n", __func__, req, req->request,
587	     req->reply);
588	WARN_ON(!RB_EMPTY_NODE(&req->node));
589
590	if (req->reply)
591		ceph_msg_put(req->reply);
592	if (req->request)
593		ceph_msg_put(req->request);
594
595	kfree(req);
596}
597
598static void put_generic_request(struct ceph_mon_generic_request *req)
599{
600	if (req)
601		kref_put(&req->kref, release_generic_request);
602}
603
604static void get_generic_request(struct ceph_mon_generic_request *req)
605{
606	kref_get(&req->kref);
607}
608
609static struct ceph_mon_generic_request *
610alloc_generic_request(struct ceph_mon_client *monc, gfp_t gfp)
611{
612	struct ceph_mon_generic_request *req;
613
614	req = kzalloc(sizeof(*req), gfp);
615	if (!req)
616		return NULL;
617
618	req->monc = monc;
619	kref_init(&req->kref);
620	RB_CLEAR_NODE(&req->node);
621	init_completion(&req->completion);
622
623	dout("%s greq %p\n", __func__, req);
624	return req;
625}
626
627static void register_generic_request(struct ceph_mon_generic_request *req)
628{
629	struct ceph_mon_client *monc = req->monc;
630
631	WARN_ON(req->tid);
632
633	get_generic_request(req);
634	req->tid = ++monc->last_tid;
635	insert_generic_request(&monc->generic_request_tree, req);
636}
637
638static void send_generic_request(struct ceph_mon_client *monc,
639				 struct ceph_mon_generic_request *req)
640{
641	WARN_ON(!req->tid);
642
643	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
644	req->request->hdr.tid = cpu_to_le64(req->tid);
645	ceph_con_send(&monc->con, ceph_msg_get(req->request));
646}
647
648static void __finish_generic_request(struct ceph_mon_generic_request *req)
649{
650	struct ceph_mon_client *monc = req->monc;
651
652	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
653	erase_generic_request(&monc->generic_request_tree, req);
654
655	ceph_msg_revoke(req->request);
656	ceph_msg_revoke_incoming(req->reply);
657}
658
659static void finish_generic_request(struct ceph_mon_generic_request *req)
660{
661	__finish_generic_request(req);
662	put_generic_request(req);
663}
664
665static void complete_generic_request(struct ceph_mon_generic_request *req)
666{
667	if (req->complete_cb)
668		req->complete_cb(req);
669	else
670		complete_all(&req->completion);
671	put_generic_request(req);
672}
673
674static void cancel_generic_request(struct ceph_mon_generic_request *req)
675{
676	struct ceph_mon_client *monc = req->monc;
677	struct ceph_mon_generic_request *lookup_req;
678
679	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
680
681	mutex_lock(&monc->mutex);
682	lookup_req = lookup_generic_request(&monc->generic_request_tree,
683					    req->tid);
684	if (lookup_req) {
685		WARN_ON(lookup_req != req);
686		finish_generic_request(req);
687	}
688
689	mutex_unlock(&monc->mutex);
690}
691
692static int wait_generic_request(struct ceph_mon_generic_request *req)
693{
694	int ret;
695
696	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
697	ret = wait_for_completion_interruptible(&req->completion);
698	if (ret)
699		cancel_generic_request(req);
700	else
701		ret = req->result; /* completed */
702
703	return ret;
704}
705
706static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
707					 struct ceph_msg_header *hdr,
708					 int *skip)
709{
710	struct ceph_mon_client *monc = con->private;
711	struct ceph_mon_generic_request *req;
712	u64 tid = le64_to_cpu(hdr->tid);
713	struct ceph_msg *m;
714
715	mutex_lock(&monc->mutex);
716	req = lookup_generic_request(&monc->generic_request_tree, tid);
717	if (!req) {
718		dout("get_generic_reply %lld dne\n", tid);
719		*skip = 1;
720		m = NULL;
721	} else {
722		dout("get_generic_reply %lld got %p\n", tid, req->reply);
723		*skip = 0;
724		m = ceph_msg_get(req->reply);
725		/*
726		 * we don't need to track the connection reading into
727		 * this reply because we only have one open connection
728		 * at a time, ever.
729		 */
730	}
731	mutex_unlock(&monc->mutex);
732	return m;
733}
734
735/*
736 * statfs
737 */
738static void handle_statfs_reply(struct ceph_mon_client *monc,
739				struct ceph_msg *msg)
740{
741	struct ceph_mon_generic_request *req;
742	struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
743	u64 tid = le64_to_cpu(msg->hdr.tid);
744
745	dout("%s msg %p tid %llu\n", __func__, msg, tid);
746
747	if (msg->front.iov_len != sizeof(*reply))
748		goto bad;
749
750	mutex_lock(&monc->mutex);
751	req = lookup_generic_request(&monc->generic_request_tree, tid);
752	if (!req) {
753		mutex_unlock(&monc->mutex);
754		return;
755	}
756
757	req->result = 0;
758	*req->u.st = reply->st; /* struct */
759	__finish_generic_request(req);
760	mutex_unlock(&monc->mutex);
761
762	complete_generic_request(req);
763	return;
764
765bad:
766	pr_err("corrupt statfs reply, tid %llu\n", tid);
767	ceph_msg_dump(msg);
768}
769
770/*
771 * Do a synchronous statfs().
772 */
773int ceph_monc_do_statfs(struct ceph_mon_client *monc, u64 data_pool,
774			struct ceph_statfs *buf)
775{
776	struct ceph_mon_generic_request *req;
777	struct ceph_mon_statfs *h;
778	int ret = -ENOMEM;
779
780	req = alloc_generic_request(monc, GFP_NOFS);
781	if (!req)
782		goto out;
783
784	req->request = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), GFP_NOFS,
785				    true);
786	if (!req->request)
787		goto out;
788
789	req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 64, GFP_NOFS, true);
790	if (!req->reply)
791		goto out;
792
793	req->u.st = buf;
794	req->request->hdr.version = cpu_to_le16(2);
795
796	mutex_lock(&monc->mutex);
797	register_generic_request(req);
798	/* fill out request */
799	h = req->request->front.iov_base;
800	h->monhdr.have_version = 0;
801	h->monhdr.session_mon = cpu_to_le16(-1);
802	h->monhdr.session_mon_tid = 0;
803	h->fsid = monc->monmap->fsid;
804	h->contains_data_pool = (data_pool != CEPH_NOPOOL);
805	h->data_pool = cpu_to_le64(data_pool);
806	send_generic_request(monc, req);
807	mutex_unlock(&monc->mutex);
808
809	ret = wait_generic_request(req);
810out:
811	put_generic_request(req);
812	return ret;
813}
814EXPORT_SYMBOL(ceph_monc_do_statfs);
815
816static void handle_get_version_reply(struct ceph_mon_client *monc,
817				     struct ceph_msg *msg)
818{
819	struct ceph_mon_generic_request *req;
820	u64 tid = le64_to_cpu(msg->hdr.tid);
821	void *p = msg->front.iov_base;
822	void *end = p + msg->front_alloc_len;
823	u64 handle;
824
825	dout("%s msg %p tid %llu\n", __func__, msg, tid);
826
827	ceph_decode_need(&p, end, 2*sizeof(u64), bad);
828	handle = ceph_decode_64(&p);
829	if (tid != 0 && tid != handle)
830		goto bad;
831
832	mutex_lock(&monc->mutex);
833	req = lookup_generic_request(&monc->generic_request_tree, handle);
834	if (!req) {
835		mutex_unlock(&monc->mutex);
836		return;
837	}
838
839	req->result = 0;
840	req->u.newest = ceph_decode_64(&p);
841	__finish_generic_request(req);
842	mutex_unlock(&monc->mutex);
843
844	complete_generic_request(req);
845	return;
846
847bad:
848	pr_err("corrupt mon_get_version reply, tid %llu\n", tid);
849	ceph_msg_dump(msg);
850}
851
852static struct ceph_mon_generic_request *
853__ceph_monc_get_version(struct ceph_mon_client *monc, const char *what,
854			ceph_monc_callback_t cb, u64 private_data)
855{
856	struct ceph_mon_generic_request *req;
857
858	req = alloc_generic_request(monc, GFP_NOIO);
859	if (!req)
860		goto err_put_req;
861
862	req->request = ceph_msg_new(CEPH_MSG_MON_GET_VERSION,
863				    sizeof(u64) + sizeof(u32) + strlen(what),
864				    GFP_NOIO, true);
865	if (!req->request)
866		goto err_put_req;
867
868	req->reply = ceph_msg_new(CEPH_MSG_MON_GET_VERSION_REPLY, 32, GFP_NOIO,
869				  true);
870	if (!req->reply)
871		goto err_put_req;
872
873	req->complete_cb = cb;
874	req->private_data = private_data;
875
876	mutex_lock(&monc->mutex);
877	register_generic_request(req);
878	{
879		void *p = req->request->front.iov_base;
880		void *const end = p + req->request->front_alloc_len;
881
882		ceph_encode_64(&p, req->tid); /* handle */
883		ceph_encode_string(&p, end, what, strlen(what));
884		WARN_ON(p != end);
885	}
886	send_generic_request(monc, req);
887	mutex_unlock(&monc->mutex);
888
889	return req;
890
891err_put_req:
892	put_generic_request(req);
893	return ERR_PTR(-ENOMEM);
894}
895
896/*
897 * Send MMonGetVersion and wait for the reply.
898 *
899 * @what: one of "mdsmap", "osdmap" or "monmap"
900 */
901int ceph_monc_get_version(struct ceph_mon_client *monc, const char *what,
902			  u64 *newest)
903{
904	struct ceph_mon_generic_request *req;
905	int ret;
906
907	req = __ceph_monc_get_version(monc, what, NULL, 0);
908	if (IS_ERR(req))
909		return PTR_ERR(req);
910
911	ret = wait_generic_request(req);
912	if (!ret)
913		*newest = req->u.newest;
914
915	put_generic_request(req);
916	return ret;
917}
918EXPORT_SYMBOL(ceph_monc_get_version);
919
920/*
921 * Send MMonGetVersion,
922 *
923 * @what: one of "mdsmap", "osdmap" or "monmap"
924 */
925int ceph_monc_get_version_async(struct ceph_mon_client *monc, const char *what,
926				ceph_monc_callback_t cb, u64 private_data)
927{
928	struct ceph_mon_generic_request *req;
929
930	req = __ceph_monc_get_version(monc, what, cb, private_data);
931	if (IS_ERR(req))
932		return PTR_ERR(req);
933
934	put_generic_request(req);
935	return 0;
936}
937EXPORT_SYMBOL(ceph_monc_get_version_async);
938
939static void handle_command_ack(struct ceph_mon_client *monc,
940			       struct ceph_msg *msg)
941{
942	struct ceph_mon_generic_request *req;
943	void *p = msg->front.iov_base;
944	void *const end = p + msg->front_alloc_len;
945	u64 tid = le64_to_cpu(msg->hdr.tid);
946
947	dout("%s msg %p tid %llu\n", __func__, msg, tid);
948
949	ceph_decode_need(&p, end, sizeof(struct ceph_mon_request_header) +
950							    sizeof(u32), bad);
951	p += sizeof(struct ceph_mon_request_header);
952
953	mutex_lock(&monc->mutex);
954	req = lookup_generic_request(&monc->generic_request_tree, tid);
955	if (!req) {
956		mutex_unlock(&monc->mutex);
957		return;
958	}
959
960	req->result = ceph_decode_32(&p);
961	__finish_generic_request(req);
962	mutex_unlock(&monc->mutex);
963
964	complete_generic_request(req);
965	return;
966
967bad:
968	pr_err("corrupt mon_command ack, tid %llu\n", tid);
969	ceph_msg_dump(msg);
970}
971
972static __printf(2, 0)
973int do_mon_command_vargs(struct ceph_mon_client *monc, const char *fmt,
974			 va_list ap)
975{
976	struct ceph_mon_generic_request *req;
977	struct ceph_mon_command *h;
978	int ret = -ENOMEM;
979	int len;
980
981	req = alloc_generic_request(monc, GFP_NOIO);
982	if (!req)
983		goto out;
984
985	req->request = ceph_msg_new(CEPH_MSG_MON_COMMAND, 256, GFP_NOIO, true);
986	if (!req->request)
987		goto out;
988
989	req->reply = ceph_msg_new(CEPH_MSG_MON_COMMAND_ACK, 512, GFP_NOIO,
990				  true);
991	if (!req->reply)
992		goto out;
993
994	mutex_lock(&monc->mutex);
995	register_generic_request(req);
996	h = req->request->front.iov_base;
997	h->monhdr.have_version = 0;
998	h->monhdr.session_mon = cpu_to_le16(-1);
999	h->monhdr.session_mon_tid = 0;
1000	h->fsid = monc->monmap->fsid;
1001	h->num_strs = cpu_to_le32(1);
1002	len = vsprintf(h->str, fmt, ap);
1003	h->str_len = cpu_to_le32(len);
1004	send_generic_request(monc, req);
1005	mutex_unlock(&monc->mutex);
1006
1007	ret = wait_generic_request(req);
1008out:
1009	put_generic_request(req);
1010	return ret;
1011}
1012
1013static __printf(2, 3)
1014int do_mon_command(struct ceph_mon_client *monc, const char *fmt, ...)
1015{
1016	va_list ap;
1017	int ret;
1018
1019	va_start(ap, fmt);
1020	ret = do_mon_command_vargs(monc, fmt, ap);
1021	va_end(ap);
1022	return ret;
1023}
1024
1025int ceph_monc_blocklist_add(struct ceph_mon_client *monc,
1026			    struct ceph_entity_addr *client_addr)
1027{
1028	int ret;
1029
1030	ret = do_mon_command(monc,
1031			     "{ \"prefix\": \"osd blocklist\", \
1032				\"blocklistop\": \"add\", \
1033				\"addr\": \"%pISpc/%u\" }",
1034			     &client_addr->in_addr,
1035			     le32_to_cpu(client_addr->nonce));
1036	if (ret == -EINVAL) {
1037		/*
1038		 * The monitor returns EINVAL on an unrecognized command.
1039		 * Try the legacy command -- it is exactly the same except
1040		 * for the name.
1041		 */
1042		ret = do_mon_command(monc,
1043				     "{ \"prefix\": \"osd blacklist\", \
1044					\"blacklistop\": \"add\", \
1045					\"addr\": \"%pISpc/%u\" }",
1046				     &client_addr->in_addr,
1047				     le32_to_cpu(client_addr->nonce));
1048	}
1049	if (ret)
1050		return ret;
1051
1052	/*
1053	 * Make sure we have the osdmap that includes the blocklist
1054	 * entry.  This is needed to ensure that the OSDs pick up the
1055	 * new blocklist before processing any future requests from
1056	 * this client.
1057	 */
1058	return ceph_wait_for_latest_osdmap(monc->client, 0);
1059}
1060EXPORT_SYMBOL(ceph_monc_blocklist_add);
1061
1062/*
1063 * Resend pending generic requests.
1064 */
1065static void __resend_generic_request(struct ceph_mon_client *monc)
1066{
1067	struct ceph_mon_generic_request *req;
1068	struct rb_node *p;
1069
1070	for (p = rb_first(&monc->generic_request_tree); p; p = rb_next(p)) {
1071		req = rb_entry(p, struct ceph_mon_generic_request, node);
1072		ceph_msg_revoke(req->request);
1073		ceph_msg_revoke_incoming(req->reply);
1074		ceph_con_send(&monc->con, ceph_msg_get(req->request));
1075	}
1076}
1077
1078/*
1079 * Delayed work.  If we haven't mounted yet, retry.  Otherwise,
1080 * renew/retry subscription as needed (in case it is timing out, or we
1081 * got an ENOMEM).  And keep the monitor connection alive.
1082 */
1083static void delayed_work(struct work_struct *work)
1084{
1085	struct ceph_mon_client *monc =
1086		container_of(work, struct ceph_mon_client, delayed_work.work);
1087
1088	dout("monc delayed_work\n");
1089	mutex_lock(&monc->mutex);
1090	if (monc->hunting) {
1091		dout("%s continuing hunt\n", __func__);
1092		reopen_session(monc);
1093	} else {
1094		int is_auth = ceph_auth_is_authenticated(monc->auth);
1095		if (ceph_con_keepalive_expired(&monc->con,
1096					       CEPH_MONC_PING_TIMEOUT)) {
1097			dout("monc keepalive timeout\n");
1098			is_auth = 0;
1099			reopen_session(monc);
1100		}
1101
1102		if (!monc->hunting) {
1103			ceph_con_keepalive(&monc->con);
1104			__validate_auth(monc);
1105			un_backoff(monc);
1106		}
1107
1108		if (is_auth &&
1109		    !(monc->con.peer_features & CEPH_FEATURE_MON_STATEFUL_SUB)) {
1110			unsigned long now = jiffies;
1111
1112			dout("%s renew subs? now %lu renew after %lu\n",
1113			     __func__, now, monc->sub_renew_after);
1114			if (time_after_eq(now, monc->sub_renew_after))
1115				__send_subscribe(monc);
1116		}
1117	}
1118	__schedule_delayed(monc);
1119	mutex_unlock(&monc->mutex);
1120}
1121
1122/*
1123 * On startup, we build a temporary monmap populated with the IPs
1124 * provided by mount(2).
1125 */
1126static int build_initial_monmap(struct ceph_mon_client *monc)
1127{
1128	__le32 my_type = ceph_msgr2(monc->client) ?
1129		CEPH_ENTITY_ADDR_TYPE_MSGR2 : CEPH_ENTITY_ADDR_TYPE_LEGACY;
1130	struct ceph_options *opt = monc->client->options;
1131	int num_mon = opt->num_mon;
1132	int i;
1133
1134	/* build initial monmap */
1135	monc->monmap = kzalloc(struct_size(monc->monmap, mon_inst, num_mon),
1136			       GFP_KERNEL);
1137	if (!monc->monmap)
1138		return -ENOMEM;
1139	monc->monmap->num_mon = num_mon;
1140
1141	for (i = 0; i < num_mon; i++) {
1142		struct ceph_entity_inst *inst = &monc->monmap->mon_inst[i];
1143
1144		memcpy(&inst->addr.in_addr, &opt->mon_addr[i].in_addr,
1145		       sizeof(inst->addr.in_addr));
1146		inst->addr.type = my_type;
1147		inst->addr.nonce = 0;
1148		inst->name.type = CEPH_ENTITY_TYPE_MON;
1149		inst->name.num = cpu_to_le64(i);
1150	}
1151	return 0;
1152}
1153
1154int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
1155{
1156	int err;
1157
1158	dout("init\n");
1159	memset(monc, 0, sizeof(*monc));
1160	monc->client = cl;
1161	mutex_init(&monc->mutex);
1162
1163	err = build_initial_monmap(monc);
1164	if (err)
1165		goto out;
1166
1167	/* connection */
1168	/* authentication */
1169	monc->auth = ceph_auth_init(cl->options->name, cl->options->key,
1170				    cl->options->con_modes);
1171	if (IS_ERR(monc->auth)) {
1172		err = PTR_ERR(monc->auth);
1173		goto out_monmap;
1174	}
1175	monc->auth->want_keys =
1176		CEPH_ENTITY_TYPE_AUTH | CEPH_ENTITY_TYPE_MON |
1177		CEPH_ENTITY_TYPE_OSD | CEPH_ENTITY_TYPE_MDS;
1178
1179	/* msgs */
1180	err = -ENOMEM;
1181	monc->m_subscribe_ack = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE_ACK,
1182				     sizeof(struct ceph_mon_subscribe_ack),
1183				     GFP_KERNEL, true);
1184	if (!monc->m_subscribe_ack)
1185		goto out_auth;
1186
1187	monc->m_subscribe = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 128,
1188					 GFP_KERNEL, true);
1189	if (!monc->m_subscribe)
1190		goto out_subscribe_ack;
1191
1192	monc->m_auth_reply = ceph_msg_new(CEPH_MSG_AUTH_REPLY, 4096,
1193					  GFP_KERNEL, true);
1194	if (!monc->m_auth_reply)
1195		goto out_subscribe;
1196
1197	monc->m_auth = ceph_msg_new(CEPH_MSG_AUTH, 4096, GFP_KERNEL, true);
1198	monc->pending_auth = 0;
1199	if (!monc->m_auth)
1200		goto out_auth_reply;
1201
1202	ceph_con_init(&monc->con, monc, &mon_con_ops,
1203		      &monc->client->msgr);
1204
1205	monc->cur_mon = -1;
1206	monc->had_a_connection = false;
1207	monc->hunt_mult = 1;
1208
1209	INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
1210	monc->generic_request_tree = RB_ROOT;
1211	monc->last_tid = 0;
1212
1213	monc->fs_cluster_id = CEPH_FS_CLUSTER_ID_NONE;
1214
1215	return 0;
1216
1217out_auth_reply:
1218	ceph_msg_put(monc->m_auth_reply);
1219out_subscribe:
1220	ceph_msg_put(monc->m_subscribe);
1221out_subscribe_ack:
1222	ceph_msg_put(monc->m_subscribe_ack);
1223out_auth:
1224	ceph_auth_destroy(monc->auth);
1225out_monmap:
1226	kfree(monc->monmap);
1227out:
1228	return err;
1229}
1230EXPORT_SYMBOL(ceph_monc_init);
1231
1232void ceph_monc_stop(struct ceph_mon_client *monc)
1233{
1234	dout("stop\n");
1235	cancel_delayed_work_sync(&monc->delayed_work);
1236
1237	mutex_lock(&monc->mutex);
1238	__close_session(monc);
1239	monc->cur_mon = -1;
1240	mutex_unlock(&monc->mutex);
1241
1242	/*
1243	 * flush msgr queue before we destroy ourselves to ensure that:
1244	 *  - any work that references our embedded con is finished.
1245	 *  - any osd_client or other work that may reference an authorizer
1246	 *    finishes before we shut down the auth subsystem.
1247	 */
1248	ceph_msgr_flush();
1249
1250	ceph_auth_destroy(monc->auth);
1251
1252	WARN_ON(!RB_EMPTY_ROOT(&monc->generic_request_tree));
1253
1254	ceph_msg_put(monc->m_auth);
1255	ceph_msg_put(monc->m_auth_reply);
1256	ceph_msg_put(monc->m_subscribe);
1257	ceph_msg_put(monc->m_subscribe_ack);
1258
1259	kfree(monc->monmap);
1260}
1261EXPORT_SYMBOL(ceph_monc_stop);
1262
1263static void finish_hunting(struct ceph_mon_client *monc)
1264{
1265	if (monc->hunting) {
1266		dout("%s found mon%d\n", __func__, monc->cur_mon);
1267		monc->hunting = false;
1268		monc->had_a_connection = true;
1269		un_backoff(monc);
1270		__schedule_delayed(monc);
1271	}
1272}
1273
1274static void finish_auth(struct ceph_mon_client *monc, int auth_err,
1275			bool was_authed)
1276{
1277	dout("%s auth_err %d was_authed %d\n", __func__, auth_err, was_authed);
1278	WARN_ON(auth_err > 0);
1279
1280	monc->pending_auth = 0;
1281	if (auth_err) {
1282		monc->client->auth_err = auth_err;
1283		wake_up_all(&monc->client->auth_wq);
1284		return;
1285	}
1286
1287	if (!was_authed && ceph_auth_is_authenticated(monc->auth)) {
1288		dout("%s authenticated, starting session global_id %llu\n",
1289		     __func__, monc->auth->global_id);
1290
1291		monc->client->msgr.inst.name.type = CEPH_ENTITY_TYPE_CLIENT;
1292		monc->client->msgr.inst.name.num =
1293					cpu_to_le64(monc->auth->global_id);
1294
1295		__send_subscribe(monc);
1296		__resend_generic_request(monc);
1297
1298		pr_info("mon%d %s session established\n", monc->cur_mon,
1299			ceph_pr_addr(&monc->con.peer_addr));
1300	}
1301}
1302
1303static void handle_auth_reply(struct ceph_mon_client *monc,
1304			      struct ceph_msg *msg)
1305{
1306	bool was_authed;
1307	int ret;
1308
1309	mutex_lock(&monc->mutex);
1310	was_authed = ceph_auth_is_authenticated(monc->auth);
1311	ret = ceph_handle_auth_reply(monc->auth, msg->front.iov_base,
1312				     msg->front.iov_len,
1313				     monc->m_auth->front.iov_base,
1314				     monc->m_auth->front_alloc_len);
1315	if (ret > 0) {
1316		__send_prepared_auth_request(monc, ret);
1317	} else {
1318		finish_auth(monc, ret, was_authed);
1319		finish_hunting(monc);
1320	}
1321	mutex_unlock(&monc->mutex);
1322}
1323
1324static int __validate_auth(struct ceph_mon_client *monc)
1325{
1326	int ret;
1327
1328	if (monc->pending_auth)
1329		return 0;
1330
1331	ret = ceph_build_auth(monc->auth, monc->m_auth->front.iov_base,
1332			      monc->m_auth->front_alloc_len);
1333	if (ret <= 0)
1334		return ret; /* either an error, or no need to authenticate */
1335	__send_prepared_auth_request(monc, ret);
1336	return 0;
1337}
1338
1339int ceph_monc_validate_auth(struct ceph_mon_client *monc)
1340{
1341	int ret;
1342
1343	mutex_lock(&monc->mutex);
1344	ret = __validate_auth(monc);
1345	mutex_unlock(&monc->mutex);
1346	return ret;
1347}
1348EXPORT_SYMBOL(ceph_monc_validate_auth);
1349
1350static int mon_get_auth_request(struct ceph_connection *con,
1351				void *buf, int *buf_len,
1352				void **authorizer, int *authorizer_len)
1353{
1354	struct ceph_mon_client *monc = con->private;
1355	int ret;
1356
1357	mutex_lock(&monc->mutex);
1358	ret = ceph_auth_get_request(monc->auth, buf, *buf_len);
1359	mutex_unlock(&monc->mutex);
1360	if (ret < 0)
1361		return ret;
1362
1363	*buf_len = ret;
1364	*authorizer = NULL;
1365	*authorizer_len = 0;
1366	return 0;
1367}
1368
1369static int mon_handle_auth_reply_more(struct ceph_connection *con,
1370				      void *reply, int reply_len,
1371				      void *buf, int *buf_len,
1372				      void **authorizer, int *authorizer_len)
1373{
1374	struct ceph_mon_client *monc = con->private;
1375	int ret;
1376
1377	mutex_lock(&monc->mutex);
1378	ret = ceph_auth_handle_reply_more(monc->auth, reply, reply_len,
1379					  buf, *buf_len);
1380	mutex_unlock(&monc->mutex);
1381	if (ret < 0)
1382		return ret;
1383
1384	*buf_len = ret;
1385	*authorizer = NULL;
1386	*authorizer_len = 0;
1387	return 0;
1388}
1389
1390static int mon_handle_auth_done(struct ceph_connection *con,
1391				u64 global_id, void *reply, int reply_len,
1392				u8 *session_key, int *session_key_len,
1393				u8 *con_secret, int *con_secret_len)
1394{
1395	struct ceph_mon_client *monc = con->private;
1396	bool was_authed;
1397	int ret;
1398
1399	mutex_lock(&monc->mutex);
1400	WARN_ON(!monc->hunting);
1401	was_authed = ceph_auth_is_authenticated(monc->auth);
1402	ret = ceph_auth_handle_reply_done(monc->auth, global_id,
1403					  reply, reply_len,
1404					  session_key, session_key_len,
1405					  con_secret, con_secret_len);
1406	finish_auth(monc, ret, was_authed);
1407	if (!ret)
1408		finish_hunting(monc);
1409	mutex_unlock(&monc->mutex);
1410	return 0;
1411}
1412
1413static int mon_handle_auth_bad_method(struct ceph_connection *con,
1414				      int used_proto, int result,
1415				      const int *allowed_protos, int proto_cnt,
1416				      const int *allowed_modes, int mode_cnt)
1417{
1418	struct ceph_mon_client *monc = con->private;
1419	bool was_authed;
1420
1421	mutex_lock(&monc->mutex);
1422	WARN_ON(!monc->hunting);
1423	was_authed = ceph_auth_is_authenticated(monc->auth);
1424	ceph_auth_handle_bad_method(monc->auth, used_proto, result,
1425				    allowed_protos, proto_cnt,
1426				    allowed_modes, mode_cnt);
1427	finish_auth(monc, -EACCES, was_authed);
1428	mutex_unlock(&monc->mutex);
1429	return 0;
1430}
1431
1432/*
1433 * handle incoming message
1434 */
1435static void mon_dispatch(struct ceph_connection *con, struct ceph_msg *msg)
1436{
1437	struct ceph_mon_client *monc = con->private;
1438	int type = le16_to_cpu(msg->hdr.type);
1439
1440	switch (type) {
1441	case CEPH_MSG_AUTH_REPLY:
1442		handle_auth_reply(monc, msg);
1443		break;
1444
1445	case CEPH_MSG_MON_SUBSCRIBE_ACK:
1446		handle_subscribe_ack(monc, msg);
1447		break;
1448
1449	case CEPH_MSG_STATFS_REPLY:
1450		handle_statfs_reply(monc, msg);
1451		break;
1452
1453	case CEPH_MSG_MON_GET_VERSION_REPLY:
1454		handle_get_version_reply(monc, msg);
1455		break;
1456
1457	case CEPH_MSG_MON_COMMAND_ACK:
1458		handle_command_ack(monc, msg);
1459		break;
1460
1461	case CEPH_MSG_MON_MAP:
1462		ceph_monc_handle_map(monc, msg);
1463		break;
1464
1465	case CEPH_MSG_OSD_MAP:
1466		ceph_osdc_handle_map(&monc->client->osdc, msg);
1467		break;
1468
1469	default:
1470		/* can the chained handler handle it? */
1471		if (monc->client->extra_mon_dispatch &&
1472		    monc->client->extra_mon_dispatch(monc->client, msg) == 0)
1473			break;
1474
1475		pr_err("received unknown message type %d %s\n", type,
1476		       ceph_msg_type_name(type));
1477	}
1478	ceph_msg_put(msg);
1479}
1480
1481/*
1482 * Allocate memory for incoming message
1483 */
1484static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
1485				      struct ceph_msg_header *hdr,
1486				      int *skip)
1487{
1488	struct ceph_mon_client *monc = con->private;
1489	int type = le16_to_cpu(hdr->type);
1490	int front_len = le32_to_cpu(hdr->front_len);
1491	struct ceph_msg *m = NULL;
1492
1493	*skip = 0;
1494
1495	switch (type) {
1496	case CEPH_MSG_MON_SUBSCRIBE_ACK:
1497		m = ceph_msg_get(monc->m_subscribe_ack);
1498		break;
1499	case CEPH_MSG_STATFS_REPLY:
1500	case CEPH_MSG_MON_COMMAND_ACK:
1501		return get_generic_reply(con, hdr, skip);
1502	case CEPH_MSG_AUTH_REPLY:
1503		m = ceph_msg_get(monc->m_auth_reply);
1504		break;
1505	case CEPH_MSG_MON_GET_VERSION_REPLY:
1506		if (le64_to_cpu(hdr->tid) != 0)
1507			return get_generic_reply(con, hdr, skip);
1508
1509		/*
1510		 * Older OSDs don't set reply tid even if the original
1511		 * request had a non-zero tid.  Work around this weirdness
1512		 * by allocating a new message.
1513		 */
1514		fallthrough;
1515	case CEPH_MSG_MON_MAP:
1516	case CEPH_MSG_MDS_MAP:
1517	case CEPH_MSG_OSD_MAP:
1518	case CEPH_MSG_FS_MAP_USER:
1519		m = ceph_msg_new(type, front_len, GFP_NOFS, false);
1520		if (!m)
1521			return NULL;	/* ENOMEM--return skip == 0 */
1522		break;
1523	}
1524
1525	if (!m) {
1526		pr_info("alloc_msg unknown type %d\n", type);
1527		*skip = 1;
1528	} else if (front_len > m->front_alloc_len) {
1529		pr_warn("mon_alloc_msg front %d > prealloc %d (%u#%llu)\n",
1530			front_len, m->front_alloc_len,
1531			(unsigned int)con->peer_name.type,
1532			le64_to_cpu(con->peer_name.num));
1533		ceph_msg_put(m);
1534		m = ceph_msg_new(type, front_len, GFP_NOFS, false);
1535	}
1536
1537	return m;
1538}
1539
1540/*
1541 * If the monitor connection resets, pick a new monitor and resubmit
1542 * any pending requests.
1543 */
1544static void mon_fault(struct ceph_connection *con)
1545{
1546	struct ceph_mon_client *monc = con->private;
1547
1548	mutex_lock(&monc->mutex);
1549	dout("%s mon%d\n", __func__, monc->cur_mon);
1550	if (monc->cur_mon >= 0) {
1551		if (!monc->hunting) {
1552			dout("%s hunting for new mon\n", __func__);
1553			reopen_session(monc);
1554			__schedule_delayed(monc);
1555		} else {
1556			dout("%s already hunting\n", __func__);
1557		}
1558	}
1559	mutex_unlock(&monc->mutex);
1560}
1561
1562/*
1563 * We can ignore refcounting on the connection struct, as all references
1564 * will come from the messenger workqueue, which is drained prior to
1565 * mon_client destruction.
1566 */
1567static struct ceph_connection *mon_get_con(struct ceph_connection *con)
1568{
1569	return con;
1570}
1571
1572static void mon_put_con(struct ceph_connection *con)
1573{
1574}
1575
1576static const struct ceph_connection_operations mon_con_ops = {
1577	.get = mon_get_con,
1578	.put = mon_put_con,
1579	.alloc_msg = mon_alloc_msg,
1580	.dispatch = mon_dispatch,
1581	.fault = mon_fault,
1582	.get_auth_request = mon_get_auth_request,
1583	.handle_auth_reply_more = mon_handle_auth_reply_more,
1584	.handle_auth_done = mon_handle_auth_done,
1585	.handle_auth_bad_method = mon_handle_auth_bad_method,
1586};
1587