1	// SPDX-License-Identifier: GPL-2.0
2	#include <linux/ceph/ceph_debug.h>
3
4	#include <linux/crc32c.h>
5	#include <linux/ctype.h>
6	#include <linux/highmem.h>
7	#include <linux/inet.h>
8	#include <linux/kthread.h>
9	#include <linux/net.h>
10	#include <linux/nsproxy.h>
11	#include <linux/sched/mm.h>
12	#include <linux/slab.h>
13	#include <linux/socket.h>
14	#include <linux/string.h>
15	#ifdef CONFIG_BLOCK
16	#include <linux/bio.h>
17	#endif /* CONFIG_BLOCK */
18	#include <linux/dns_resolver.h>
19	#include <net/tcp.h>
20	#include <trace/events/sock.h>
21
22	#include <linux/ceph/ceph_features.h>
23	#include <linux/ceph/libceph.h>
24	#include <linux/ceph/messenger.h>
25	#include <linux/ceph/decode.h>
26	#include <linux/ceph/pagelist.h>
27	#include <linux/export.h>
28
29	/*
30	* Ceph uses the messenger to exchange ceph_msg messages with other
31	* hosts in the system. The messenger provides ordered and reliable
32	* delivery. We tolerate TCP disconnects by reconnecting (with
33	* exponential backoff) in the case of a fault (disconnection, bad
34	* crc, protocol error). Acks allow sent messages to be discarded by
35	* the sender.
36	*/
37
38	/*
39	* We track the state of the socket on a given connection using
40	* values defined below. The transition to a new socket state is
41	* handled by a function which verifies we aren't coming from an
42	* unexpected state.
43	*
44	* --------
45	* | NEW* | transient initial state
46	* --------
47	* | con_sock_state_init()
48	* v
49	* ----------
50	* | CLOSED | initialized, but no socket (and no
51	* ---------- TCP connection)
52	* ^ \
53	* | \ con_sock_state_connecting()
54	* | ----------------------
55	* | \
56	* + con_sock_state_closed() \
57	* |+--------------------------- \
58	* | \ \ \
59	* | ----------- \ \
60	* | | CLOSING | socket event; \ \
61	* | ----------- await close \ \
62	* | ^ \ |
63	* | | \ |
64	* | + con_sock_state_closing() \ |
65	* | / \ | |
66	* | / --------------- | |
67	* | / \ v v
68	* | / --------------
69	* | / -----------------| CONNECTING | socket created, TCP
70	* | | / -------------- connect initiated
71	* | | | con_sock_state_connected()
72	* | | v
73	* -------------
74	* | CONNECTED | TCP connection established
75	* -------------
76	*
77	* State values for ceph_connection->sock_state; NEW is assumed to be 0.
78	*/
79
80	#define CON_SOCK_STATE_NEW 0 /* -> CLOSED */
81	#define CON_SOCK_STATE_CLOSED 1 /* -> CONNECTING */
82	#define CON_SOCK_STATE_CONNECTING 2 /* -> CONNECTED or -> CLOSING */
83	#define CON_SOCK_STATE_CONNECTED 3 /* -> CLOSING or -> CLOSED */
84	#define CON_SOCK_STATE_CLOSING 4 /* -> CLOSED */
85
86	static bool con_flag_valid(unsigned long con_flag)
87	{
88	switch (con_flag) {
89	case CEPH_CON_F_LOSSYTX:
90	case CEPH_CON_F_KEEPALIVE_PENDING:
91	case CEPH_CON_F_WRITE_PENDING:
92	case CEPH_CON_F_SOCK_CLOSED:
93	case CEPH_CON_F_BACKOFF:
94	return true;
95	default:
96	return false;
97	}
98	}
99
100	void ceph_con_flag_clear(struct ceph_connection *con, unsigned long con_flag)
101	{
102	BUG_ON(!con_flag_valid(con_flag));
103
104	clear_bit(nr: con_flag, addr: &con->flags);
105	}
106
107	void ceph_con_flag_set(struct ceph_connection *con, unsigned long con_flag)
108	{
109	BUG_ON(!con_flag_valid(con_flag));
110
111	set_bit(nr: con_flag, addr: &con->flags);
112	}
113
114	bool ceph_con_flag_test(struct ceph_connection *con, unsigned long con_flag)
115	{
116	BUG_ON(!con_flag_valid(con_flag));
117
118	return test_bit(con_flag, &con->flags);
119	}
120
121	bool ceph_con_flag_test_and_clear(struct ceph_connection *con,
122	unsigned long con_flag)
123	{
124	BUG_ON(!con_flag_valid(con_flag));
125
126	return test_and_clear_bit(nr: con_flag, addr: &con->flags);
127	}
128
129	bool ceph_con_flag_test_and_set(struct ceph_connection *con,
130	unsigned long con_flag)
131	{
132	BUG_ON(!con_flag_valid(con_flag));
133
134	return test_and_set_bit(nr: con_flag, addr: &con->flags);
135	}
136
137	/* Slab caches for frequently-allocated structures */
138
139	static struct kmem_cache *ceph_msg_cache;
140
141	#ifdef CONFIG_LOCKDEP
142	static struct lock_class_key socket_class;
143	#endif
144
145	static void queue_con(struct ceph_connection *con);
146	static void cancel_con(struct ceph_connection *con);
147	static void ceph_con_workfn(struct work_struct *);
148	static void con_fault(struct ceph_connection *con);
149
150	/*
151	* Nicely render a sockaddr as a string. An array of formatted
152	* strings is used, to approximate reentrancy.
153	*/
154	#define ADDR_STR_COUNT_LOG 5 /* log2(# address strings in array) */
155	#define ADDR_STR_COUNT (1 << ADDR_STR_COUNT_LOG)
156	#define ADDR_STR_COUNT_MASK (ADDR_STR_COUNT - 1)
157	#define MAX_ADDR_STR_LEN 64 /* 54 is enough */
158
159	static char addr_str[ADDR_STR_COUNT][MAX_ADDR_STR_LEN];
160	static atomic_t addr_str_seq = ATOMIC_INIT(0);
161
162	struct page *ceph_zero_page; /* used in certain error cases */
163
164	const char *ceph_pr_addr(const struct ceph_entity_addr *addr)
165	{
166	int i;
167	char *s;
168	struct sockaddr_storage ss = addr->in_addr; /* align */
169	struct sockaddr_in *in4 = (struct sockaddr_in *)&ss;
170	struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&ss;
171
172	i = atomic_inc_return(v: &addr_str_seq) & ADDR_STR_COUNT_MASK;
173	s = addr_str[i];
174
175	switch (ss.ss_family) {
176	case AF_INET:
177	snprintf(buf: s, MAX_ADDR_STR_LEN, fmt: "(%d)%pI4:%hu",
178	le32_to_cpu(addr->type), &in4->sin_addr,
179	ntohs(in4->sin_port));
180	break;
181
182	case AF_INET6:
183	snprintf(buf: s, MAX_ADDR_STR_LEN, fmt: "(%d)[%pI6c]:%hu",
184	le32_to_cpu(addr->type), &in6->sin6_addr,
185	ntohs(in6->sin6_port));
186	break;
187
188	default:
189	snprintf(buf: s, MAX_ADDR_STR_LEN, fmt: "(unknown sockaddr family %hu)",
190	ss.ss_family);
191	}
192
193	return s;
194	}
195	EXPORT_SYMBOL(ceph_pr_addr);
196
197	void ceph_encode_my_addr(struct ceph_messenger *msgr)
198	{
199	if (!ceph_msgr2(from_msgr(msgr))) {
200	memcpy(&msgr->my_enc_addr, &msgr->inst.addr,
201	sizeof(msgr->my_enc_addr));
202	ceph_encode_banner_addr(a: &msgr->my_enc_addr);
203	}
204	}
205
206	/*
207	* work queue for all reading and writing to/from the socket.
208	*/
209	static struct workqueue_struct *ceph_msgr_wq;
210
211	static int ceph_msgr_slab_init(void)
212	{
213	BUG_ON(ceph_msg_cache);
214	ceph_msg_cache = KMEM_CACHE(ceph_msg, 0);
215	if (!ceph_msg_cache)
216	return -ENOMEM;
217
218	return 0;
219	}
220
221	static void ceph_msgr_slab_exit(void)
222	{
223	BUG_ON(!ceph_msg_cache);
224	kmem_cache_destroy(s: ceph_msg_cache);
225	ceph_msg_cache = NULL;
226	}
227
228	static void _ceph_msgr_exit(void)
229	{
230	if (ceph_msgr_wq) {
231	destroy_workqueue(wq: ceph_msgr_wq);
232	ceph_msgr_wq = NULL;
233	}
234
235	BUG_ON(!ceph_zero_page);
236	put_page(page: ceph_zero_page);
237	ceph_zero_page = NULL;
238
239	ceph_msgr_slab_exit();
240	}
241
242	int __init ceph_msgr_init(void)
243	{
244	if (ceph_msgr_slab_init())
245	return -ENOMEM;
246
247	BUG_ON(ceph_zero_page);
248	ceph_zero_page = ZERO_PAGE(0);
249	get_page(page: ceph_zero_page);
250
251	/*
252	* The number of active work items is limited by the number of
253	* connections, so leave @max_active at default.
254	*/
255	ceph_msgr_wq = alloc_workqueue("ceph-msgr",
256	WQ_MEM_RECLAIM | WQ_PERCPU, 0);
257	if (ceph_msgr_wq)
258	return 0;
259
260	pr_err("msgr_init failed to create workqueue\n");
261	_ceph_msgr_exit();
262
263	return -ENOMEM;
264	}
265
266	void ceph_msgr_exit(void)
267	{
268	BUG_ON(ceph_msgr_wq == NULL);
269
270	_ceph_msgr_exit();
271	}
272
273	void ceph_msgr_flush(void)
274	{
275	flush_workqueue(ceph_msgr_wq);
276	}
277	EXPORT_SYMBOL(ceph_msgr_flush);
278
279	/* Connection socket state transition functions */
280
281	static void con_sock_state_init(struct ceph_connection *con)
282	{
283	int old_state;
284
285	old_state = atomic_xchg(v: &con->sock_state, CON_SOCK_STATE_CLOSED);
286	if (WARN_ON(old_state != CON_SOCK_STATE_NEW))
287	printk("%s: unexpected old state %d\n", __func__, old_state);
288	dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
289	CON_SOCK_STATE_CLOSED);
290	}
291
292	static void con_sock_state_connecting(struct ceph_connection *con)
293	{
294	int old_state;
295
296	old_state = atomic_xchg(v: &con->sock_state, CON_SOCK_STATE_CONNECTING);
297	if (WARN_ON(old_state != CON_SOCK_STATE_CLOSED))
298	printk("%s: unexpected old state %d\n", __func__, old_state);
299	dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
300	CON_SOCK_STATE_CONNECTING);
301	}
302
303	static void con_sock_state_connected(struct ceph_connection *con)
304	{
305	int old_state;
306
307	old_state = atomic_xchg(v: &con->sock_state, CON_SOCK_STATE_CONNECTED);
308	if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTING))
309	printk("%s: unexpected old state %d\n", __func__, old_state);
310	dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
311	CON_SOCK_STATE_CONNECTED);
312	}
313
314	static void con_sock_state_closing(struct ceph_connection *con)
315	{
316	int old_state;
317
318	old_state = atomic_xchg(v: &con->sock_state, CON_SOCK_STATE_CLOSING);
319	if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTING &&
320	old_state != CON_SOCK_STATE_CONNECTED &&
321	old_state != CON_SOCK_STATE_CLOSING))
322	printk("%s: unexpected old state %d\n", __func__, old_state);
323	dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
324	CON_SOCK_STATE_CLOSING);
325	}
326
327	static void con_sock_state_closed(struct ceph_connection *con)
328	{
329	int old_state;
330
331	old_state = atomic_xchg(v: &con->sock_state, CON_SOCK_STATE_CLOSED);
332	if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTED &&
333	old_state != CON_SOCK_STATE_CLOSING &&
334	old_state != CON_SOCK_STATE_CONNECTING &&
335	old_state != CON_SOCK_STATE_CLOSED))
336	printk("%s: unexpected old state %d\n", __func__, old_state);
337	dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
338	CON_SOCK_STATE_CLOSED);
339	}
340
341	/*
342	* socket callback functions
343	*/
344
345	/* data available on socket, or listen socket received a connect */
346	static void ceph_sock_data_ready(struct sock *sk)
347	{
348	struct ceph_connection *con = sk->sk_user_data;
349
350	trace_sk_data_ready(sk);
351
352	if (atomic_read(v: &con->msgr->stopping)) {
353	return;
354	}
355
356	if (sk->sk_state != TCP_CLOSE_WAIT) {
357	dout("%s %p state = %d, queueing work\n", __func__,
358	con, con->state);
359	queue_con(con);
360	}
361	}
362
363	/* socket has buffer space for writing */
364	static void ceph_sock_write_space(struct sock *sk)
365	{
366	struct ceph_connection *con = sk->sk_user_data;
367
368	/* only queue to workqueue if there is data we want to write,
369	* and there is sufficient space in the socket buffer to accept
370	* more data. clear SOCK_NOSPACE so that ceph_sock_write_space()
371	* doesn't get called again until try_write() fills the socket
372	* buffer. See net/ipv4/tcp_input.c:tcp_check_space()
373	* and net/core/stream.c:sk_stream_write_space().
374	*/
375	if (ceph_con_flag_test(con, CEPH_CON_F_WRITE_PENDING)) {
376	if (sk_stream_is_writeable(sk)) {
377	dout("%s %p queueing write work\n", __func__, con);
378	clear_bit(nr: SOCK_NOSPACE, addr: &sk->sk_socket->flags);
379	queue_con(con);
380	}
381	} else {
382	dout("%s %p nothing to write\n", __func__, con);
383	}
384	}
385
386	/* socket's state has changed */
387	static void ceph_sock_state_change(struct sock *sk)
388	{
389	struct ceph_connection *con = sk->sk_user_data;
390
391	dout("%s %p state = %d sk_state = %u\n", __func__,
392	con, con->state, sk->sk_state);
393
394	switch (sk->sk_state) {
395	case TCP_CLOSE:
396	dout("%s TCP_CLOSE\n", __func__);
397	fallthrough;
398	case TCP_CLOSE_WAIT:
399	dout("%s TCP_CLOSE_WAIT\n", __func__);
400	con_sock_state_closing(con);
401	ceph_con_flag_set(con, CEPH_CON_F_SOCK_CLOSED);
402	queue_con(con);
403	break;
404	case TCP_ESTABLISHED:
405	dout("%s TCP_ESTABLISHED\n", __func__);
406	con_sock_state_connected(con);
407	queue_con(con);
408	break;
409	default: /* Everything else is uninteresting */
410	break;
411	}
412	}
413
414	/*
415	* set up socket callbacks
416	*/
417	static void set_sock_callbacks(struct socket *sock,
418	struct ceph_connection *con)
419	{
420	struct sock *sk = sock->sk;
421	sk->sk_user_data = con;
422	sk->sk_data_ready = ceph_sock_data_ready;
423	sk->sk_write_space = ceph_sock_write_space;
424	sk->sk_state_change = ceph_sock_state_change;
425	}
426
427
428	/*
429	* socket helpers
430	*/
431
432	/*
433	* initiate connection to a remote socket.
434	*/
435	int ceph_tcp_connect(struct ceph_connection *con)
436	{
437	struct sockaddr_storage ss = con->peer_addr.in_addr; /* align */
438	struct socket *sock;
439	unsigned int noio_flag;
440	int ret;
441
442	dout("%s con %p peer_addr %s\n", __func__, con,
443	ceph_pr_addr(&con->peer_addr));
444	BUG_ON(con->sock);
445
446	/* sock_create_kern() allocates with GFP_KERNEL */
447	noio_flag = memalloc_noio_save();
448	ret = sock_create_kern(net: read_pnet(pnet: &con->msgr->net), family: ss.ss_family,
449	type: SOCK_STREAM, IPPROTO_TCP, res: &sock);
450	memalloc_noio_restore(flags: noio_flag);
451	if (ret)
452	return ret;
453	sock->sk->sk_allocation = GFP_NOFS;
454	sock->sk->sk_use_task_frag = false;
455
456	#ifdef CONFIG_LOCKDEP
457	lockdep_set_class(&sock->sk->sk_lock, &socket_class);
458	#endif
459
460	set_sock_callbacks(sock, con);
461
462	con_sock_state_connecting(con);
463	ret = kernel_connect(sock, addr: (struct sockaddr_unsized *)&ss, addrlen: sizeof(ss),
464	O_NONBLOCK);
465	if (ret == -EINPROGRESS) {
466	dout("connect %s EINPROGRESS sk_state = %u\n",
467	ceph_pr_addr(&con->peer_addr),
468	sock->sk->sk_state);
469	} else if (ret < 0) {
470	pr_err("connect %s error %d\n",
471	ceph_pr_addr(&con->peer_addr), ret);
472	sock_release(sock);
473	return ret;
474	}
475
476	if (ceph_test_opt(from_msgr(con->msgr), TCP_NODELAY))
477	tcp_sock_set_nodelay(sk: sock->sk);
478
479	con->sock = sock;
480	return 0;
481	}
482
483	/*
484	* Shutdown/close the socket for the given connection.
485	*/
486	int ceph_con_close_socket(struct ceph_connection *con)
487	{
488	int rc = 0;
489
490	dout("%s con %p sock %p\n", __func__, con, con->sock);
491	if (con->sock) {
492	rc = con->sock->ops->shutdown(con->sock, SHUT_RDWR);
493	sock_release(sock: con->sock);
494	con->sock = NULL;
495	}
496
497	/*
498	* Forcibly clear the SOCK_CLOSED flag. It gets set
499	* independent of the connection mutex, and we could have
500	* received a socket close event before we had the chance to
501	* shut the socket down.
502	*/
503	ceph_con_flag_clear(con, CEPH_CON_F_SOCK_CLOSED);
504
505	con_sock_state_closed(con);
506	return rc;
507	}
508
509	static void ceph_con_reset_protocol(struct ceph_connection *con)
510	{
511	dout("%s con %p\n", __func__, con);
512
513	ceph_con_close_socket(con);
514	if (con->in_msg) {
515	WARN_ON(con->in_msg->con != con);
516	ceph_msg_put(msg: con->in_msg);
517	con->in_msg = NULL;
518	}
519	if (con->out_msg) {
520	WARN_ON(con->out_msg->con != con);
521	ceph_msg_put(msg: con->out_msg);
522	con->out_msg = NULL;
523	}
524	if (con->bounce_page) {
525	__free_page(con->bounce_page);
526	con->bounce_page = NULL;
527	}
528
529	if (ceph_msgr2(from_msgr(con->msgr)))
530	ceph_con_v2_reset_protocol(con);
531	else
532	ceph_con_v1_reset_protocol(con);
533	}
534
535	/*
536	* Reset a connection. Discard all incoming and outgoing messages
537	* and clear *_seq state.
538	*/
539	static void ceph_msg_remove(struct ceph_msg *msg)
540	{
541	list_del_init(entry: &msg->list_head);
542
543	ceph_msg_put(msg);
544	}
545
546	static void ceph_msg_remove_list(struct list_head *head)
547	{
548	while (!list_empty(head)) {
549	struct ceph_msg *msg = list_first_entry(head, struct ceph_msg,
550	list_head);
551	ceph_msg_remove(msg);
552	}
553	}
554
555	void ceph_con_reset_session(struct ceph_connection *con)
556	{
557	dout("%s con %p\n", __func__, con);
558
559	WARN_ON(con->in_msg);
560	WARN_ON(con->out_msg);
561	ceph_msg_remove_list(head: &con->out_queue);
562	ceph_msg_remove_list(head: &con->out_sent);
563	con->out_seq = 0;
564	con->in_seq = 0;
565	con->in_seq_acked = 0;
566
567	if (ceph_msgr2(from_msgr(con->msgr)))
568	ceph_con_v2_reset_session(con);
569	else
570	ceph_con_v1_reset_session(con);
571	}
572
573	/*
574	* mark a peer down. drop any open connections.
575	*/
576	void ceph_con_close(struct ceph_connection *con)
577	{
578	mutex_lock(&con->mutex);
579	dout("con_close %p peer %s\n", con, ceph_pr_addr(&con->peer_addr));
580	con->state = CEPH_CON_S_CLOSED;
581
582	ceph_con_flag_clear(con, CEPH_CON_F_LOSSYTX); /* so we retry next
583	connect */
584	ceph_con_flag_clear(con, CEPH_CON_F_KEEPALIVE_PENDING);
585	ceph_con_flag_clear(con, CEPH_CON_F_WRITE_PENDING);
586	ceph_con_flag_clear(con, CEPH_CON_F_BACKOFF);
587
588	ceph_con_reset_protocol(con);
589	ceph_con_reset_session(con);
590	cancel_con(con);
591	mutex_unlock(lock: &con->mutex);
592	}
593	EXPORT_SYMBOL(ceph_con_close);
594
595	/*
596	* Reopen a closed connection, with a new peer address.
597	*/
598	void ceph_con_open(struct ceph_connection *con,
599	__u8 entity_type, __u64 entity_num,
600	struct ceph_entity_addr *addr)
601	{
602	mutex_lock(&con->mutex);
603	dout("con_open %p %s\n", con, ceph_pr_addr(addr));
604
605	WARN_ON(con->state != CEPH_CON_S_CLOSED);
606	con->state = CEPH_CON_S_PREOPEN;
607
608	con->peer_name.type = (__u8) entity_type;
609	con->peer_name.num = cpu_to_le64(entity_num);
610
611	memcpy(&con->peer_addr, addr, sizeof(*addr));
612	con->delay = 0; /* reset backoff memory */
613	mutex_unlock(lock: &con->mutex);
614	queue_con(con);
615	}
616	EXPORT_SYMBOL(ceph_con_open);
617
618	/*
619	* return true if this connection ever successfully opened
620	*/
621	bool ceph_con_opened(struct ceph_connection *con)
622	{
623	if (ceph_msgr2(from_msgr(con->msgr)))
624	return ceph_con_v2_opened(con);
625
626	return ceph_con_v1_opened(con);
627	}
628
629	/*
630	* initialize a new connection.
631	*/
632	void ceph_con_init(struct ceph_connection *con, void *private,
633	const struct ceph_connection_operations *ops,
634	struct ceph_messenger *msgr)
635	{
636	dout("con_init %p\n", con);
637	memset(con, 0, sizeof(*con));
638	con->private = private;
639	con->ops = ops;
640	con->msgr = msgr;
641
642	con_sock_state_init(con);
643
644	mutex_init(&con->mutex);
645	INIT_LIST_HEAD(list: &con->out_queue);
646	INIT_LIST_HEAD(list: &con->out_sent);
647	INIT_DELAYED_WORK(&con->work, ceph_con_workfn);
648
649	con->state = CEPH_CON_S_CLOSED;
650	}
651	EXPORT_SYMBOL(ceph_con_init);
652
653	/*
654	* We maintain a global counter to order connection attempts. Get
655	* a unique seq greater than @gt.
656	*/
657	u32 ceph_get_global_seq(struct ceph_messenger *msgr, u32 gt)
658	{
659	u32 ret;
660
661	spin_lock(lock: &msgr->global_seq_lock);
662	if (msgr->global_seq < gt)
663	msgr->global_seq = gt;
664	ret = ++msgr->global_seq;
665	spin_unlock(lock: &msgr->global_seq_lock);
666	return ret;
667	}
668
669	/*
670	* Discard messages that have been acked by the server.
671	*/
672	void ceph_con_discard_sent(struct ceph_connection *con, u64 ack_seq)
673	{
674	struct ceph_msg *msg;
675	u64 seq;
676
677	dout("%s con %p ack_seq %llu\n", __func__, con, ack_seq);
678	while (!list_empty(head: &con->out_sent)) {
679	msg = list_first_entry(&con->out_sent, struct ceph_msg,
680	list_head);
681	WARN_ON(msg->needs_out_seq);
682	seq = le64_to_cpu(msg->hdr.seq);
683	if (seq > ack_seq)
684	break;
685
686	dout("%s con %p discarding msg %p seq %llu\n", __func__, con,
687	msg, seq);
688	ceph_msg_remove(msg);
689	}
690	}
691
692	/*
693	* Discard messages that have been requeued in con_fault(), up to
694	* reconnect_seq. This avoids gratuitously resending messages that
695	* the server had received and handled prior to reconnect.
696	*/
697	void ceph_con_discard_requeued(struct ceph_connection *con, u64 reconnect_seq)
698	{
699	struct ceph_msg *msg;
700	u64 seq;
701
702	dout("%s con %p reconnect_seq %llu\n", __func__, con, reconnect_seq);
703	while (!list_empty(head: &con->out_queue)) {
704	msg = list_first_entry(&con->out_queue, struct ceph_msg,
705	list_head);
706	if (msg->needs_out_seq)
707	break;
708	seq = le64_to_cpu(msg->hdr.seq);
709	if (seq > reconnect_seq)
710	break;
711
712	dout("%s con %p discarding msg %p seq %llu\n", __func__, con,
713	msg, seq);
714	ceph_msg_remove(msg);
715	}
716	}
717
718	#ifdef CONFIG_BLOCK
719
720	/*
721	* For a bio data item, a piece is whatever remains of the next
722	* entry in the current bio iovec, or the first entry in the next
723	* bio in the list.
724	*/
725	static void ceph_msg_data_bio_cursor_init(struct ceph_msg_data_cursor *cursor,
726	size_t length)
727	{
728	struct ceph_msg_data *data = cursor->data;
729	struct ceph_bio_iter *it = &cursor->bio_iter;
730
731	cursor->resid = min_t(size_t, length, data->bio_length);
732	*it = data->bio_pos;
733	if (cursor->resid < it->iter.bi_size)
734	it->iter.bi_size = cursor->resid;
735
736	BUG_ON(cursor->resid < bio_iter_len(it->bio, it->iter));
737	}
738
739	static struct page *ceph_msg_data_bio_next(struct ceph_msg_data_cursor *cursor,
740	size_t *page_offset,
741	size_t *length)
742	{
743	struct bio_vec bv = bio_iter_iovec(cursor->bio_iter.bio,
744	cursor->bio_iter.iter);
745
746	*page_offset = bv.bv_offset;
747	*length = bv.bv_len;
748	return bv.bv_page;
749	}
750
751	static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor,
752	size_t bytes)
753	{
754	struct ceph_bio_iter *it = &cursor->bio_iter;
755	struct page *page = bio_iter_page(it->bio, it->iter);
756
757	BUG_ON(bytes > cursor->resid);
758	BUG_ON(bytes > bio_iter_len(it->bio, it->iter));
759	cursor->resid -= bytes;
760	bio_advance_iter(bio: it->bio, iter: &it->iter, bytes);
761
762	if (!cursor->resid)
763	return false; /* no more data */
764
765	if (!bytes || (it->iter.bi_size && it->iter.bi_bvec_done &&
766	page == bio_iter_page(it->bio, it->iter)))
767	return false; /* more bytes to process in this segment */
768
769	if (!it->iter.bi_size) {
770	it->bio = it->bio->bi_next;
771	it->iter = it->bio->bi_iter;
772	if (cursor->resid < it->iter.bi_size)
773	it->iter.bi_size = cursor->resid;
774	}
775
776	BUG_ON(cursor->resid < bio_iter_len(it->bio, it->iter));
777	return true;
778	}
779	#endif /* CONFIG_BLOCK */
780
781	static void ceph_msg_data_bvecs_cursor_init(struct ceph_msg_data_cursor *cursor,
782	size_t length)
783	{
784	struct ceph_msg_data *data = cursor->data;
785	struct bio_vec *bvecs = data->bvec_pos.bvecs;
786
787	cursor->resid = min_t(size_t, length, data->bvec_pos.iter.bi_size);
788	cursor->bvec_iter = data->bvec_pos.iter;
789	cursor->bvec_iter.bi_size = cursor->resid;
790
791	BUG_ON(cursor->resid < bvec_iter_len(bvecs, cursor->bvec_iter));
792	}
793
794	static struct page *ceph_msg_data_bvecs_next(struct ceph_msg_data_cursor *cursor,
795	size_t *page_offset,
796	size_t *length)
797	{
798	struct bio_vec bv = bvec_iter_bvec(cursor->data->bvec_pos.bvecs,
799	cursor->bvec_iter);
800
801	*page_offset = bv.bv_offset;
802	*length = bv.bv_len;
803	return bv.bv_page;
804	}
805
806	static bool ceph_msg_data_bvecs_advance(struct ceph_msg_data_cursor *cursor,
807	size_t bytes)
808	{
809	struct bio_vec *bvecs = cursor->data->bvec_pos.bvecs;
810	struct page *page = bvec_iter_page(bvecs, cursor->bvec_iter);
811
812	BUG_ON(bytes > cursor->resid);
813	BUG_ON(bytes > bvec_iter_len(bvecs, cursor->bvec_iter));
814	cursor->resid -= bytes;
815	bvec_iter_advance(bv: bvecs, iter: &cursor->bvec_iter, bytes);
816
817	if (!cursor->resid)
818	return false; /* no more data */
819
820	if (!bytes || (cursor->bvec_iter.bi_bvec_done &&
821	page == bvec_iter_page(bvecs, cursor->bvec_iter)))
822	return false; /* more bytes to process in this segment */
823
824	BUG_ON(cursor->resid < bvec_iter_len(bvecs, cursor->bvec_iter));
825	return true;
826	}
827
828	/*
829	* For a page array, a piece comes from the first page in the array
830	* that has not already been fully consumed.
831	*/
832	static void ceph_msg_data_pages_cursor_init(struct ceph_msg_data_cursor *cursor,
833	size_t length)
834	{
835	struct ceph_msg_data *data = cursor->data;
836	int page_count;
837
838	BUG_ON(data->type != CEPH_MSG_DATA_PAGES);
839
840	BUG_ON(!data->pages);
841	BUG_ON(!data->length);
842
843	cursor->resid = min(length, data->length);
844	page_count = calc_pages_for(off: data->alignment, len: (u64)data->length);
845	cursor->page_offset = data->alignment & ~PAGE_MASK;
846	cursor->page_index = 0;
847	BUG_ON(page_count > (int)USHRT_MAX);
848	cursor->page_count = (unsigned short)page_count;
849	BUG_ON(length > SIZE_MAX - cursor->page_offset);
850	}
851
852	static struct page *
853	ceph_msg_data_pages_next(struct ceph_msg_data_cursor *cursor,
854	size_t *page_offset, size_t *length)
855	{
856	struct ceph_msg_data *data = cursor->data;
857
858	BUG_ON(data->type != CEPH_MSG_DATA_PAGES);
859
860	BUG_ON(cursor->page_index >= cursor->page_count);
861	BUG_ON(cursor->page_offset >= PAGE_SIZE);
862
863	*page_offset = cursor->page_offset;
864	*length = min_t(size_t, cursor->resid, PAGE_SIZE - *page_offset);
865	return data->pages[cursor->page_index];
866	}
867
868	static bool ceph_msg_data_pages_advance(struct ceph_msg_data_cursor *cursor,
869	size_t bytes)
870	{
871	BUG_ON(cursor->data->type != CEPH_MSG_DATA_PAGES);
872
873	BUG_ON(cursor->page_offset + bytes > PAGE_SIZE);
874
875	/* Advance the cursor page offset */
876
877	cursor->resid -= bytes;
878	cursor->page_offset = (cursor->page_offset + bytes) & ~PAGE_MASK;
879	if (!bytes || cursor->page_offset)
880	return false; /* more bytes to process in the current page */
881
882	if (!cursor->resid)
883	return false; /* no more data */
884
885	/* Move on to the next page; offset is already at 0 */
886
887	BUG_ON(cursor->page_index >= cursor->page_count);
888	cursor->page_index++;
889	return true;
890	}
891
892	/*
893	* For a pagelist, a piece is whatever remains to be consumed in the
894	* first page in the list, or the front of the next page.
895	*/
896	static void
897	ceph_msg_data_pagelist_cursor_init(struct ceph_msg_data_cursor *cursor,
898	size_t length)
899	{
900	struct ceph_msg_data *data = cursor->data;
901	struct ceph_pagelist *pagelist;
902	struct page *page;
903
904	BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST);
905
906	pagelist = data->pagelist;
907	BUG_ON(!pagelist);
908
909	if (!length)
910	return; /* pagelist can be assigned but empty */
911
912	BUG_ON(list_empty(&pagelist->head));
913	page = list_first_entry(&pagelist->head, struct page, lru);
914
915	cursor->resid = min(length, pagelist->length);
916	cursor->page = page;
917	cursor->offset = 0;
918	}
919
920	static struct page *
921	ceph_msg_data_pagelist_next(struct ceph_msg_data_cursor *cursor,
922	size_t *page_offset, size_t *length)
923	{
924	struct ceph_msg_data *data = cursor->data;
925	struct ceph_pagelist *pagelist;
926
927	BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST);
928
929	pagelist = data->pagelist;
930	BUG_ON(!pagelist);
931
932	BUG_ON(!cursor->page);
933	BUG_ON(cursor->offset + cursor->resid != pagelist->length);
934
935	/* offset of first page in pagelist is always 0 */
936	*page_offset = cursor->offset & ~PAGE_MASK;
937	*length = min_t(size_t, cursor->resid, PAGE_SIZE - *page_offset);
938	return cursor->page;
939	}
940
941	static bool ceph_msg_data_pagelist_advance(struct ceph_msg_data_cursor *cursor,
942	size_t bytes)
943	{
944	struct ceph_msg_data *data = cursor->data;
945	struct ceph_pagelist *pagelist;
946
947	BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST);
948
949	pagelist = data->pagelist;
950	BUG_ON(!pagelist);
951
952	BUG_ON(cursor->offset + cursor->resid != pagelist->length);
953	BUG_ON((cursor->offset & ~PAGE_MASK) + bytes > PAGE_SIZE);
954
955	/* Advance the cursor offset */
956
957	cursor->resid -= bytes;
958	cursor->offset += bytes;
959	/* offset of first page in pagelist is always 0 */
960	if (!bytes || cursor->offset & ~PAGE_MASK)
961	return false; /* more bytes to process in the current page */
962
963	if (!cursor->resid)
964	return false; /* no more data */
965
966	/* Move on to the next page */
967
968	BUG_ON(list_is_last(&cursor->page->lru, &pagelist->head));
969	cursor->page = list_next_entry(cursor->page, lru);
970	return true;
971	}
972
973	static void ceph_msg_data_iter_cursor_init(struct ceph_msg_data_cursor *cursor,
974	size_t length)
975	{
976	struct ceph_msg_data *data = cursor->data;
977
978	cursor->iov_iter = data->iter;
979	cursor->lastlen = 0;
980	iov_iter_truncate(i: &cursor->iov_iter, count: length);
981	cursor->resid = iov_iter_count(i: &cursor->iov_iter);
982	}
983
984	static struct page *ceph_msg_data_iter_next(struct ceph_msg_data_cursor *cursor,
985	size_t *page_offset, size_t *length)
986	{
987	struct page *page;
988	ssize_t len;
989
990	if (cursor->lastlen)
991	iov_iter_revert(i: &cursor->iov_iter, bytes: cursor->lastlen);
992
993	len = iov_iter_get_pages2(i: &cursor->iov_iter, pages: &page, PAGE_SIZE,
994	maxpages: 1, start: page_offset);
995	BUG_ON(len < 0);
996
997	cursor->lastlen = len;
998
999	/*
1000	* FIXME: The assumption is that the pages represented by the iov_iter
1001	* are pinned, with the references held by the upper-level
1002	* callers, or by virtue of being under writeback. Eventually,
1003	* we'll get an iov_iter_get_pages2 variant that doesn't take
1004	* page refs. Until then, just put the page ref.
1005	*/
1006	VM_BUG_ON_PAGE(!PageWriteback(page) && page_count(page) < 2, page);
1007	put_page(page);
1008
1009	*length = min_t(size_t, len, cursor->resid);
1010	return page;
1011	}
1012
1013	static bool ceph_msg_data_iter_advance(struct ceph_msg_data_cursor *cursor,
1014	size_t bytes)
1015	{
1016	BUG_ON(bytes > cursor->resid);
1017	cursor->resid -= bytes;
1018
1019	if (bytes < cursor->lastlen) {
1020	cursor->lastlen -= bytes;
1021	} else {
1022	iov_iter_advance(i: &cursor->iov_iter, bytes: bytes - cursor->lastlen);
1023	cursor->lastlen = 0;
1024	}
1025
1026	return cursor->resid;
1027	}
1028
1029	/*
1030	* Message data is handled (sent or received) in pieces, where each
1031	* piece resides on a single page. The network layer might not
1032	* consume an entire piece at once. A data item's cursor keeps
1033	* track of which piece is next to process and how much remains to
1034	* be processed in that piece. It also tracks whether the current
1035	* piece is the last one in the data item.
1036	*/
1037	static void __ceph_msg_data_cursor_init(struct ceph_msg_data_cursor *cursor)
1038	{
1039	size_t length = cursor->total_resid;
1040
1041	switch (cursor->data->type) {
1042	case CEPH_MSG_DATA_PAGELIST:
1043	ceph_msg_data_pagelist_cursor_init(cursor, length);
1044	break;
1045	case CEPH_MSG_DATA_PAGES:
1046	ceph_msg_data_pages_cursor_init(cursor, length);
1047	break;
1048	#ifdef CONFIG_BLOCK
1049	case CEPH_MSG_DATA_BIO:
1050	ceph_msg_data_bio_cursor_init(cursor, length);
1051	break;
1052	#endif /* CONFIG_BLOCK */
1053	case CEPH_MSG_DATA_BVECS:
1054	ceph_msg_data_bvecs_cursor_init(cursor, length);
1055	break;
1056	case CEPH_MSG_DATA_ITER:
1057	ceph_msg_data_iter_cursor_init(cursor, length);
1058	break;
1059	case CEPH_MSG_DATA_NONE:
1060	default:
1061	/* BUG(); */
1062	break;
1063	}
1064	cursor->need_crc = true;
1065	}
1066
1067	void ceph_msg_data_cursor_init(struct ceph_msg_data_cursor *cursor,
1068	struct ceph_msg *msg, size_t length)
1069	{
1070	BUG_ON(!length);
1071	BUG_ON(length > msg->data_length);
1072	BUG_ON(!msg->num_data_items);
1073
1074	cursor->total_resid = length;
1075	cursor->data = msg->data;
1076	cursor->sr_resid = 0;
1077
1078	__ceph_msg_data_cursor_init(cursor);
1079	}
1080
1081	/*
1082	* Return the page containing the next piece to process for a given
1083	* data item, and supply the page offset and length of that piece.
1084	* Indicate whether this is the last piece in this data item.
1085	*/
1086	struct page *ceph_msg_data_next(struct ceph_msg_data_cursor *cursor,
1087	size_t *page_offset, size_t *length)
1088	{
1089	struct page *page;
1090
1091	switch (cursor->data->type) {
1092	case CEPH_MSG_DATA_PAGELIST:
1093	page = ceph_msg_data_pagelist_next(cursor, page_offset, length);
1094	break;
1095	case CEPH_MSG_DATA_PAGES:
1096	page = ceph_msg_data_pages_next(cursor, page_offset, length);
1097	break;
1098	#ifdef CONFIG_BLOCK
1099	case CEPH_MSG_DATA_BIO:
1100	page = ceph_msg_data_bio_next(cursor, page_offset, length);
1101	break;
1102	#endif /* CONFIG_BLOCK */
1103	case CEPH_MSG_DATA_BVECS:
1104	page = ceph_msg_data_bvecs_next(cursor, page_offset, length);
1105	break;
1106	case CEPH_MSG_DATA_ITER:
1107	page = ceph_msg_data_iter_next(cursor, page_offset, length);
1108	break;
1109	case CEPH_MSG_DATA_NONE:
1110	default:
1111	page = NULL;
1112	break;
1113	}
1114
1115	BUG_ON(!page);
1116	BUG_ON(*page_offset + *length > PAGE_SIZE);
1117	BUG_ON(!*length);
1118	BUG_ON(*length > cursor->resid);
1119
1120	return page;
1121	}
1122
1123	/*
1124	* Returns true if the result moves the cursor on to the next piece
1125	* of the data item.
1126	*/
1127	void ceph_msg_data_advance(struct ceph_msg_data_cursor *cursor, size_t bytes)
1128	{
1129	bool new_piece;
1130
1131	BUG_ON(bytes > cursor->resid);
1132	switch (cursor->data->type) {
1133	case CEPH_MSG_DATA_PAGELIST:
1134	new_piece = ceph_msg_data_pagelist_advance(cursor, bytes);
1135	break;
1136	case CEPH_MSG_DATA_PAGES:
1137	new_piece = ceph_msg_data_pages_advance(cursor, bytes);
1138	break;
1139	#ifdef CONFIG_BLOCK
1140	case CEPH_MSG_DATA_BIO:
1141	new_piece = ceph_msg_data_bio_advance(cursor, bytes);
1142	break;
1143	#endif /* CONFIG_BLOCK */
1144	case CEPH_MSG_DATA_BVECS:
1145	new_piece = ceph_msg_data_bvecs_advance(cursor, bytes);
1146	break;
1147	case CEPH_MSG_DATA_ITER:
1148	new_piece = ceph_msg_data_iter_advance(cursor, bytes);
1149	break;
1150	case CEPH_MSG_DATA_NONE:
1151	default:
1152	BUG();
1153	break;
1154	}
1155	cursor->total_resid -= bytes;
1156
1157	if (!cursor->resid && cursor->total_resid) {
1158	cursor->data++;
1159	__ceph_msg_data_cursor_init(cursor);
1160	new_piece = true;
1161	}
1162	cursor->need_crc = new_piece;
1163	}
1164
1165	u32 ceph_crc32c_page(u32 crc, struct page *page, unsigned int page_offset,
1166	unsigned int length)
1167	{
1168	char *kaddr;
1169
1170	kaddr = kmap(page);
1171	BUG_ON(kaddr == NULL);
1172	crc = crc32c(crc, p: kaddr + page_offset, len: length);
1173	kunmap(page);
1174
1175	return crc;
1176	}
1177
1178	bool ceph_addr_is_blank(const struct ceph_entity_addr *addr)
1179	{
1180	struct sockaddr_storage ss = addr->in_addr; /* align */
1181	struct in_addr *addr4 = &((struct sockaddr_in *)&ss)->sin_addr;
1182	struct in6_addr *addr6 = &((struct sockaddr_in6 *)&ss)->sin6_addr;
1183
1184	switch (ss.ss_family) {
1185	case AF_INET:
1186	return addr4->s_addr == htonl(INADDR_ANY);
1187	case AF_INET6:
1188	return ipv6_addr_any(a: addr6);
1189	default:
1190	return true;
1191	}
1192	}
1193	EXPORT_SYMBOL(ceph_addr_is_blank);
1194
1195	int ceph_addr_port(const struct ceph_entity_addr *addr)
1196	{
1197	switch (get_unaligned(&addr->in_addr.ss_family)) {
1198	case AF_INET:
1199	return ntohs(get_unaligned(&((struct sockaddr_in *)&addr->in_addr)->sin_port));
1200	case AF_INET6:
1201	return ntohs(get_unaligned(&((struct sockaddr_in6 *)&addr->in_addr)->sin6_port));
1202	}
1203	return 0;
1204	}
1205
1206	void ceph_addr_set_port(struct ceph_entity_addr *addr, int p)
1207	{
1208	switch (get_unaligned(&addr->in_addr.ss_family)) {
1209	case AF_INET:
1210	put_unaligned(htons(p), &((struct sockaddr_in *)&addr->in_addr)->sin_port);
1211	break;
1212	case AF_INET6:
1213	put_unaligned(htons(p), &((struct sockaddr_in6 *)&addr->in_addr)->sin6_port);
1214	break;
1215	}
1216	}
1217
1218	/*
1219	* Unlike other *_pton function semantics, zero indicates success.
1220	*/
1221	static int ceph_pton(const char *str, size_t len, struct ceph_entity_addr *addr,
1222	char delim, const char **ipend)
1223	{
1224	memset(&addr->in_addr, 0, sizeof(addr->in_addr));
1225
1226	if (in4_pton(src: str, srclen: len, dst: (u8 *)&((struct sockaddr_in *)&addr->in_addr)->sin_addr.s_addr, delim, end: ipend)) {
1227	put_unaligned(AF_INET, &addr->in_addr.ss_family);
1228	return 0;
1229	}
1230
1231	if (in6_pton(src: str, srclen: len, dst: (u8 *)&((struct sockaddr_in6 *)&addr->in_addr)->sin6_addr.s6_addr, delim, end: ipend)) {
1232	put_unaligned(AF_INET6, &addr->in_addr.ss_family);
1233	return 0;
1234	}
1235
1236	return -EINVAL;
1237	}
1238
1239	/*
1240	* Extract hostname string and resolve using kernel DNS facility.
1241	*/
1242	#ifdef CONFIG_CEPH_LIB_USE_DNS_RESOLVER
1243	static int ceph_dns_resolve_name(const char *name, size_t namelen,
1244	struct ceph_entity_addr *addr, char delim, const char **ipend)
1245	{
1246	const char *end, *delim_p;
1247	char *colon_p, *ip_addr = NULL;
1248	int ip_len, ret;
1249
1250	/*
1251	* The end of the hostname occurs immediately preceding the delimiter or
1252	* the port marker (':') where the delimiter takes precedence.
1253	*/
1254	delim_p = memchr(p: name, c: delim, size: namelen);
1255	colon_p = memchr(p: name, c: ':', size: namelen);
1256
1257	if (delim_p && colon_p)
1258	end = min(delim_p, colon_p);
1259	else if (!delim_p && colon_p)
1260	end = colon_p;
1261	else {
1262	end = delim_p;
1263	if (!end) /* case: hostname:/ */
1264	end = name + namelen;
1265	}
1266
1267	if (end <= name)
1268	return -EINVAL;
1269
1270	/* do dns_resolve upcall */
1271	ip_len = dns_query(current->nsproxy->net_ns,
1272	NULL, name, namelen: end - name, NULL, result: &ip_addr, NULL, invalidate: false);
1273	if (ip_len > 0)
1274	ret = ceph_pton(str: ip_addr, len: ip_len, addr, delim: -1, NULL);
1275	else
1276	ret = -ESRCH;
1277
1278	kfree(objp: ip_addr);
1279
1280	*ipend = end;
1281
1282	pr_info("resolve '%.*s' (ret=%d): %s\n", (int)(end - name), name,
1283	ret, ret ? "failed" : ceph_pr_addr(addr));
1284
1285	return ret;
1286	}
1287	#else
1288	static inline int ceph_dns_resolve_name(const char *name, size_t namelen,
1289	struct ceph_entity_addr *addr, char delim, const char **ipend)
1290	{
1291	return -EINVAL;
1292	}
1293	#endif
1294
1295	/*
1296	* Parse a server name (IP or hostname). If a valid IP address is not found
1297	* then try to extract a hostname to resolve using userspace DNS upcall.
1298	*/
1299	static int ceph_parse_server_name(const char *name, size_t namelen,
1300	struct ceph_entity_addr *addr, char delim, const char **ipend)
1301	{
1302	int ret;
1303
1304	ret = ceph_pton(str: name, len: namelen, addr, delim, ipend);
1305	if (ret)
1306	ret = ceph_dns_resolve_name(name, namelen, addr, delim, ipend);
1307
1308	return ret;
1309	}
1310
1311	/*
1312	* Parse an ip[:port] list into an addr array. Use the default
1313	* monitor port if a port isn't specified.
1314	*/
1315	int ceph_parse_ips(const char *c, const char *end,
1316	struct ceph_entity_addr *addr,
1317	int max_count, int *count, char delim)
1318	{
1319	int i, ret = -EINVAL;
1320	const char *p = c;
1321
1322	dout("parse_ips on '%.*s'\n", (int)(end-c), c);
1323	for (i = 0; i < max_count; i++) {
1324	char cur_delim = delim;
1325	const char *ipend;
1326	int port;
1327
1328	if (*p == '[') {
1329	cur_delim = ']';
1330	p++;
1331	}
1332
1333	ret = ceph_parse_server_name(name: p, namelen: end - p, addr: &addr[i], delim: cur_delim,
1334	ipend: &ipend);
1335	if (ret)
1336	goto bad;
1337	ret = -EINVAL;
1338
1339	p = ipend;
1340
1341	if (cur_delim == ']') {
1342	if (*p != ']') {
1343	dout("missing matching ']'\n");
1344	goto bad;
1345	}
1346	p++;
1347	}
1348
1349	/* port? */
1350	if (p < end && *p == ':') {
1351	port = 0;
1352	p++;
1353	while (p < end && *p >= '0' && *p <= '9') {
1354	port = (port * 10) + (*p - '0');
1355	p++;
1356	}
1357	if (port == 0)
1358	port = CEPH_MON_PORT;
1359	else if (port > 65535)
1360	goto bad;
1361	} else {
1362	port = CEPH_MON_PORT;
1363	}
1364
1365	ceph_addr_set_port(addr: &addr[i], p: port);
1366	/*
1367	* We want the type to be set according to ms_mode
1368	* option, but options are normally parsed after mon
1369	* addresses. Rather than complicating parsing, set
1370	* to LEGACY and override in build_initial_monmap()
1371	* for mon addresses and ceph_messenger_init() for
1372	* ip option.
1373	*/
1374	addr[i].type = CEPH_ENTITY_ADDR_TYPE_LEGACY;
1375	addr[i].nonce = 0;
1376
1377	dout("%s got %s\n", __func__, ceph_pr_addr(&addr[i]));
1378
1379	if (p == end)
1380	break;
1381	if (*p != delim)
1382	goto bad;
1383	p++;
1384	}
1385
1386	if (p != end)
1387	goto bad;
1388
1389	if (count)
1390	*count = i + 1;
1391	return 0;
1392
1393	bad:
1394	return ret;
1395	}
1396
1397	/*
1398	* Process message. This happens in the worker thread. The callback should
1399	* be careful not to do anything that waits on other incoming messages or it
1400	* may deadlock.
1401	*/
1402	void ceph_con_process_message(struct ceph_connection *con)
1403	{
1404	struct ceph_msg *msg = con->in_msg;
1405
1406	BUG_ON(con->in_msg->con != con);
1407	con->in_msg = NULL;
1408
1409	/* if first message, set peer_name */
1410	if (con->peer_name.type == 0)
1411	con->peer_name = msg->hdr.src;
1412
1413	con->in_seq++;
1414	mutex_unlock(lock: &con->mutex);
1415
1416	dout("===== %p %llu from %s%lld %d=%s len %d+%d+%d (%u %u %u) =====\n",
1417	msg, le64_to_cpu(msg->hdr.seq),
1418	ENTITY_NAME(msg->hdr.src),
1419	le16_to_cpu(msg->hdr.type),
1420	ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
1421	le32_to_cpu(msg->hdr.front_len),
1422	le32_to_cpu(msg->hdr.middle_len),
1423	le32_to_cpu(msg->hdr.data_len),
1424	con->in_front_crc, con->in_middle_crc, con->in_data_crc);
1425	con->ops->dispatch(con, msg);
1426
1427	mutex_lock(&con->mutex);
1428	}
1429
1430	/*
1431	* Atomically queue work on a connection after the specified delay.
1432	* Bump @con reference to avoid races with connection teardown.
1433	* Returns 0 if work was queued, or an error code otherwise.
1434	*/
1435	static int queue_con_delay(struct ceph_connection *con, unsigned long delay)
1436	{
1437	if (!con->ops->get(con)) {
1438	dout("%s %p ref count 0\n", __func__, con);
1439	return -ENOENT;
1440	}
1441
1442	if (delay >= HZ)
1443	delay = round_jiffies_relative(j: delay);
1444
1445	dout("%s %p %lu\n", __func__, con, delay);
1446	if (!queue_delayed_work(wq: ceph_msgr_wq, dwork: &con->work, delay)) {
1447	dout("%s %p - already queued\n", __func__, con);
1448	con->ops->put(con);
1449	return -EBUSY;
1450	}
1451
1452	return 0;
1453	}
1454
1455	static void queue_con(struct ceph_connection *con)
1456	{
1457	(void) queue_con_delay(con, delay: 0);
1458	}
1459
1460	static void cancel_con(struct ceph_connection *con)
1461	{
1462	if (cancel_delayed_work(dwork: &con->work)) {
1463	dout("%s %p\n", __func__, con);
1464	con->ops->put(con);
1465	}
1466	}
1467
1468	static bool con_sock_closed(struct ceph_connection *con)
1469	{
1470	if (!ceph_con_flag_test_and_clear(con, CEPH_CON_F_SOCK_CLOSED))
1471	return false;
1472
1473	#define CASE(x) \
1474	case CEPH_CON_S_ ## x: \
1475	con->error_msg = "socket closed (con state " #x ")"; \
1476	break;
1477
1478	switch (con->state) {
1479	CASE(CLOSED);
1480	CASE(PREOPEN);
1481	CASE(V1_BANNER);
1482	CASE(V1_CONNECT_MSG);
1483	CASE(V2_BANNER_PREFIX);
1484	CASE(V2_BANNER_PAYLOAD);
1485	CASE(V2_HELLO);
1486	CASE(V2_AUTH);
1487	CASE(V2_AUTH_SIGNATURE);
1488	CASE(V2_SESSION_CONNECT);
1489	CASE(V2_SESSION_RECONNECT);
1490	CASE(OPEN);
1491	CASE(STANDBY);
1492	default:
1493	BUG();
1494	}
1495	#undef CASE
1496
1497	return true;
1498	}
1499
1500	static bool con_backoff(struct ceph_connection *con)
1501	{
1502	int ret;
1503
1504	if (!ceph_con_flag_test_and_clear(con, CEPH_CON_F_BACKOFF))
1505	return false;
1506
1507	ret = queue_con_delay(con, delay: con->delay);
1508	if (ret) {
1509	dout("%s: con %p FAILED to back off %lu\n", __func__,
1510	con, con->delay);
1511	BUG_ON(ret == -ENOENT);
1512	ceph_con_flag_set(con, CEPH_CON_F_BACKOFF);
1513	}
1514
1515	return true;
1516	}
1517
1518	/* Finish fault handling; con->mutex must *not* be held here */
1519
1520	static void con_fault_finish(struct ceph_connection *con)
1521	{
1522	dout("%s %p\n", __func__, con);
1523
1524	/*
1525	* in case we faulted due to authentication, invalidate our
1526	* current tickets so that we can get new ones.
1527	*/
1528	if (!ceph_msgr2(from_msgr(con->msgr)) && con->v1.auth_retry) {
1529	dout("auth_retry %d, invalidating\n", con->v1.auth_retry);
1530	if (con->ops->invalidate_authorizer)
1531	con->ops->invalidate_authorizer(con);
1532	con->v1.auth_retry = 0;
1533	}
1534
1535	if (con->ops->fault)
1536	con->ops->fault(con);
1537	}
1538
1539	/*
1540	* Do some work on a connection. Drop a connection ref when we're done.
1541	*/
1542	static void ceph_con_workfn(struct work_struct *work)
1543	{
1544	struct ceph_connection *con = container_of(work, struct ceph_connection,
1545	work.work);
1546	bool fault;
1547
1548	mutex_lock(&con->mutex);
1549	while (true) {
1550	int ret;
1551
1552	if ((fault = con_sock_closed(con))) {
1553	dout("%s: con %p SOCK_CLOSED\n", __func__, con);
1554	break;
1555	}
1556	if (con_backoff(con)) {
1557	dout("%s: con %p BACKOFF\n", __func__, con);
1558	break;
1559	}
1560	if (con->state == CEPH_CON_S_STANDBY) {
1561	dout("%s: con %p STANDBY\n", __func__, con);
1562	break;
1563	}
1564	if (con->state == CEPH_CON_S_CLOSED) {
1565	dout("%s: con %p CLOSED\n", __func__, con);
1566	BUG_ON(con->sock);
1567	break;
1568	}
1569	if (con->state == CEPH_CON_S_PREOPEN) {
1570	dout("%s: con %p PREOPEN\n", __func__, con);
1571	BUG_ON(con->sock);
1572	}
1573
1574	if (ceph_msgr2(from_msgr(con->msgr)))
1575	ret = ceph_con_v2_try_read(con);
1576	else
1577	ret = ceph_con_v1_try_read(con);
1578	if (ret < 0) {
1579	if (ret == -EAGAIN)
1580	continue;
1581	if (!con->error_msg)
1582	con->error_msg = "socket error on read";
1583	fault = true;
1584	break;
1585	}
1586
1587	if (ceph_msgr2(from_msgr(con->msgr)))
1588	ret = ceph_con_v2_try_write(con);
1589	else
1590	ret = ceph_con_v1_try_write(con);
1591	if (ret < 0) {
1592	if (ret == -EAGAIN)
1593	continue;
1594	if (!con->error_msg)
1595	con->error_msg = "socket error on write";
1596	fault = true;
1597	}
1598
1599	break; /* If we make it to here, we're done */
1600	}
1601	if (fault)
1602	con_fault(con);
1603	mutex_unlock(lock: &con->mutex);
1604
1605	if (fault)
1606	con_fault_finish(con);
1607
1608	con->ops->put(con);
1609	}
1610
1611	/*
1612	* Generic error/fault handler. A retry mechanism is used with
1613	* exponential backoff
1614	*/
1615	static void con_fault(struct ceph_connection *con)
1616	{
1617	dout("fault %p state %d to peer %s\n",
1618	con, con->state, ceph_pr_addr(&con->peer_addr));
1619
1620	pr_warn("%s%lld %s %s\n", ENTITY_NAME(con->peer_name),
1621	ceph_pr_addr(&con->peer_addr), con->error_msg);
1622	con->error_msg = NULL;
1623
1624	WARN_ON(con->state == CEPH_CON_S_STANDBY ||
1625	con->state == CEPH_CON_S_CLOSED);
1626
1627	ceph_con_reset_protocol(con);
1628
1629	if (ceph_con_flag_test(con, CEPH_CON_F_LOSSYTX)) {
1630	dout("fault on LOSSYTX channel, marking CLOSED\n");
1631	con->state = CEPH_CON_S_CLOSED;
1632	return;
1633	}
1634
1635	/* Requeue anything that hasn't been acked */
1636	list_splice_init(list: &con->out_sent, head: &con->out_queue);
1637
1638	/* If there are no messages queued or keepalive pending, place
1639	* the connection in a STANDBY state */
1640	if (list_empty(head: &con->out_queue) &&
1641	!ceph_con_flag_test(con, CEPH_CON_F_KEEPALIVE_PENDING)) {
1642	dout("fault %p setting STANDBY clearing WRITE_PENDING\n", con);
1643	ceph_con_flag_clear(con, CEPH_CON_F_WRITE_PENDING);
1644	con->state = CEPH_CON_S_STANDBY;
1645	} else {
1646	/* retry after a delay. */
1647	con->state = CEPH_CON_S_PREOPEN;
1648	if (!con->delay) {
1649	con->delay = BASE_DELAY_INTERVAL;
1650	} else if (con->delay < MAX_DELAY_INTERVAL) {
1651	con->delay *= 2;
1652	if (con->delay > MAX_DELAY_INTERVAL)
1653	con->delay = MAX_DELAY_INTERVAL;
1654	}
1655	ceph_con_flag_set(con, CEPH_CON_F_BACKOFF);
1656	queue_con(con);
1657	}
1658	}
1659
1660	void ceph_messenger_reset_nonce(struct ceph_messenger *msgr)
1661	{
1662	u32 nonce = le32_to_cpu(msgr->inst.addr.nonce) + 1000000;
1663	msgr->inst.addr.nonce = cpu_to_le32(nonce);
1664	ceph_encode_my_addr(msgr);
1665	}
1666
1667	/*
1668	* initialize a new messenger instance
1669	*/
1670	void ceph_messenger_init(struct ceph_messenger *msgr,
1671	struct ceph_entity_addr *myaddr)
1672	{
1673	spin_lock_init(&msgr->global_seq_lock);
1674
1675	if (myaddr) {
1676	memcpy(&msgr->inst.addr.in_addr, &myaddr->in_addr,
1677	sizeof(msgr->inst.addr.in_addr));
1678	ceph_addr_set_port(addr: &msgr->inst.addr, p: 0);
1679	}
1680
1681	/*
1682	* Since nautilus, clients are identified using type ANY.
1683	* For msgr1, ceph_encode_banner_addr() munges it to NONE.
1684	*/
1685	msgr->inst.addr.type = CEPH_ENTITY_ADDR_TYPE_ANY;
1686
1687	/* generate a random non-zero nonce */
1688	do {
1689	get_random_bytes(buf: &msgr->inst.addr.nonce,
1690	len: sizeof(msgr->inst.addr.nonce));
1691	} while (!msgr->inst.addr.nonce);
1692	ceph_encode_my_addr(msgr);
1693
1694	atomic_set(v: &msgr->stopping, i: 0);
1695	write_pnet(pnet: &msgr->net, net: get_net(current->nsproxy->net_ns));
1696
1697	dout("%s %p\n", __func__, msgr);
1698	}
1699
1700	void ceph_messenger_fini(struct ceph_messenger *msgr)
1701	{
1702	put_net(net: read_pnet(pnet: &msgr->net));
1703	}
1704
1705	static void msg_con_set(struct ceph_msg *msg, struct ceph_connection *con)
1706	{
1707	if (msg->con)
1708	msg->con->ops->put(msg->con);
1709
1710	msg->con = con ? con->ops->get(con) : NULL;
1711	BUG_ON(msg->con != con);
1712	}
1713
1714	static void clear_standby(struct ceph_connection *con)
1715	{
1716	/* come back from STANDBY? */
1717	if (con->state == CEPH_CON_S_STANDBY) {
1718	dout("clear_standby %p\n", con);
1719	con->state = CEPH_CON_S_PREOPEN;
1720	if (!ceph_msgr2(from_msgr(con->msgr)))
1721	con->v1.connect_seq++;
1722	WARN_ON(ceph_con_flag_test(con, CEPH_CON_F_WRITE_PENDING));
1723	WARN_ON(ceph_con_flag_test(con, CEPH_CON_F_KEEPALIVE_PENDING));
1724	}
1725	}
1726
1727	/*
1728	* Queue up an outgoing message on the given connection.
1729	*
1730	* Consumes a ref on @msg.
1731	*/
1732	void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg)
1733	{
1734	/* set src+dst */
1735	msg->hdr.src = con->msgr->inst.name;
1736	BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len));
1737	msg->needs_out_seq = true;
1738
1739	mutex_lock(&con->mutex);
1740
1741	if (con->state == CEPH_CON_S_CLOSED) {
1742	dout("con_send %p closed, dropping %p\n", con, msg);
1743	ceph_msg_put(msg);
1744	mutex_unlock(lock: &con->mutex);
1745	return;
1746	}
1747
1748	msg_con_set(msg, con);
1749
1750	BUG_ON(!list_empty(&msg->list_head));
1751	list_add_tail(new: &msg->list_head, head: &con->out_queue);
1752	dout("----- %p to %s%lld %d=%s len %d+%d+%d -----\n", msg,
1753	ENTITY_NAME(con->peer_name), le16_to_cpu(msg->hdr.type),
1754	ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
1755	le32_to_cpu(msg->hdr.front_len),
1756	le32_to_cpu(msg->hdr.middle_len),
1757	le32_to_cpu(msg->hdr.data_len));
1758
1759	clear_standby(con);
1760	mutex_unlock(lock: &con->mutex);
1761
1762	/* if there wasn't anything waiting to send before, queue
1763	* new work */
1764	if (!ceph_con_flag_test_and_set(con, CEPH_CON_F_WRITE_PENDING))
1765	queue_con(con);
1766	}
1767	EXPORT_SYMBOL(ceph_con_send);
1768
1769	/*
1770	* Revoke a message that was previously queued for send
1771	*/
1772	void ceph_msg_revoke(struct ceph_msg *msg)
1773	{
1774	struct ceph_connection *con = msg->con;
1775
1776	if (!con) {
1777	dout("%s msg %p null con\n", __func__, msg);
1778	return; /* Message not in our possession */
1779	}
1780
1781	mutex_lock(&con->mutex);
1782	if (list_empty(head: &msg->list_head)) {
1783	WARN_ON(con->out_msg == msg);
1784	dout("%s con %p msg %p not linked\n", __func__, con, msg);
1785	mutex_unlock(lock: &con->mutex);
1786	return;
1787	}
1788
1789	dout("%s con %p msg %p was linked\n", __func__, con, msg);
1790	msg->hdr.seq = 0;
1791	ceph_msg_remove(msg);
1792
1793	if (con->out_msg == msg) {
1794	WARN_ON(con->state != CEPH_CON_S_OPEN);
1795	dout("%s con %p msg %p was sending\n", __func__, con, msg);
1796	if (ceph_msgr2(from_msgr(con->msgr)))
1797	ceph_con_v2_revoke(con, msg);
1798	else
1799	ceph_con_v1_revoke(con, msg);
1800	ceph_msg_put(msg: con->out_msg);
1801	con->out_msg = NULL;
1802	} else {
1803	dout("%s con %p msg %p not current, out_msg %p\n", __func__,
1804	con, msg, con->out_msg);
1805	}
1806	mutex_unlock(lock: &con->mutex);
1807	}
1808
1809	/*
1810	* Revoke a message that we may be reading data into
1811	*/
1812	void ceph_msg_revoke_incoming(struct ceph_msg *msg)
1813	{
1814	struct ceph_connection *con = msg->con;
1815
1816	if (!con) {
1817	dout("%s msg %p null con\n", __func__, msg);
1818	return; /* Message not in our possession */
1819	}
1820
1821	mutex_lock(&con->mutex);
1822	if (con->in_msg == msg) {
1823	WARN_ON(con->state != CEPH_CON_S_OPEN);
1824	dout("%s con %p msg %p was recving\n", __func__, con, msg);
1825	if (ceph_msgr2(from_msgr(con->msgr)))
1826	ceph_con_v2_revoke_incoming(con);
1827	else
1828	ceph_con_v1_revoke_incoming(con);
1829	ceph_msg_put(msg: con->in_msg);
1830	con->in_msg = NULL;
1831	} else {
1832	dout("%s con %p msg %p not current, in_msg %p\n", __func__,
1833	con, msg, con->in_msg);
1834	}
1835	mutex_unlock(lock: &con->mutex);
1836	}
1837
1838	/*
1839	* Queue a keepalive byte to ensure the tcp connection is alive.
1840	*/
1841	void ceph_con_keepalive(struct ceph_connection *con)
1842	{
1843	dout("con_keepalive %p\n", con);
1844	mutex_lock(&con->mutex);
1845	clear_standby(con);
1846	ceph_con_flag_set(con, CEPH_CON_F_KEEPALIVE_PENDING);
1847	mutex_unlock(lock: &con->mutex);
1848
1849	if (!ceph_con_flag_test_and_set(con, CEPH_CON_F_WRITE_PENDING))
1850	queue_con(con);
1851	}
1852	EXPORT_SYMBOL(ceph_con_keepalive);
1853
1854	bool ceph_con_keepalive_expired(struct ceph_connection *con,
1855	unsigned long interval)
1856	{
1857	if (interval > 0 &&
1858	(con->peer_features & CEPH_FEATURE_MSGR_KEEPALIVE2)) {
1859	struct timespec64 now;
1860	struct timespec64 ts;
1861	ktime_get_real_ts64(tv: &now);
1862	jiffies_to_timespec64(jiffies: interval, value: &ts);
1863	ts = timespec64_add(lhs: con->last_keepalive_ack, rhs: ts);
1864	return timespec64_compare(lhs: &now, rhs: &ts) >= 0;
1865	}
1866	return false;
1867	}
1868
1869	static struct ceph_msg_data *ceph_msg_data_add(struct ceph_msg *msg)
1870	{
1871	BUG_ON(msg->num_data_items >= msg->max_data_items);
1872	return &msg->data[msg->num_data_items++];
1873	}
1874
1875	static void ceph_msg_data_destroy(struct ceph_msg_data *data)
1876	{
1877	if (data->type == CEPH_MSG_DATA_PAGES && data->own_pages) {
1878	int num_pages = calc_pages_for(off: data->alignment, len: data->length);
1879	ceph_release_page_vector(pages: data->pages, num_pages);
1880	} else if (data->type == CEPH_MSG_DATA_PAGELIST) {
1881	ceph_pagelist_release(pl: data->pagelist);
1882	}
1883	}
1884
1885	void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages,
1886	size_t length, size_t alignment, bool own_pages)
1887	{
1888	struct ceph_msg_data *data;
1889
1890	BUG_ON(!pages);
1891	BUG_ON(!length);
1892
1893	data = ceph_msg_data_add(msg);
1894	data->type = CEPH_MSG_DATA_PAGES;
1895	data->pages = pages;
1896	data->length = length;
1897	data->alignment = alignment & ~PAGE_MASK;
1898	data->own_pages = own_pages;
1899
1900	msg->data_length += length;
1901	}
1902	EXPORT_SYMBOL(ceph_msg_data_add_pages);
1903
1904	void ceph_msg_data_add_pagelist(struct ceph_msg *msg,
1905	struct ceph_pagelist *pagelist)
1906	{
1907	struct ceph_msg_data *data;
1908
1909	BUG_ON(!pagelist);
1910	BUG_ON(!pagelist->length);
1911
1912	data = ceph_msg_data_add(msg);
1913	data->type = CEPH_MSG_DATA_PAGELIST;
1914	refcount_inc(r: &pagelist->refcnt);
1915	data->pagelist = pagelist;
1916
1917	msg->data_length += pagelist->length;
1918	}
1919	EXPORT_SYMBOL(ceph_msg_data_add_pagelist);
1920
1921	#ifdef CONFIG_BLOCK
1922	void ceph_msg_data_add_bio(struct ceph_msg *msg, struct ceph_bio_iter *bio_pos,
1923	u32 length)
1924	{
1925	struct ceph_msg_data *data;
1926
1927	data = ceph_msg_data_add(msg);
1928	data->type = CEPH_MSG_DATA_BIO;
1929	data->bio_pos = *bio_pos;
1930	data->bio_length = length;
1931
1932	msg->data_length += length;
1933	}
1934	EXPORT_SYMBOL(ceph_msg_data_add_bio);
1935	#endif /* CONFIG_BLOCK */
1936
1937	void ceph_msg_data_add_bvecs(struct ceph_msg *msg,
1938	struct ceph_bvec_iter *bvec_pos)
1939	{
1940	struct ceph_msg_data *data;
1941
1942	data = ceph_msg_data_add(msg);
1943	data->type = CEPH_MSG_DATA_BVECS;
1944	data->bvec_pos = *bvec_pos;
1945
1946	msg->data_length += bvec_pos->iter.bi_size;
1947	}
1948	EXPORT_SYMBOL(ceph_msg_data_add_bvecs);
1949
1950	void ceph_msg_data_add_iter(struct ceph_msg *msg,
1951	struct iov_iter *iter)
1952	{
1953	struct ceph_msg_data *data;
1954
1955	data = ceph_msg_data_add(msg);
1956	data->type = CEPH_MSG_DATA_ITER;
1957	data->iter = *iter;
1958
1959	msg->data_length += iov_iter_count(i: &data->iter);
1960	}
1961
1962	/*
1963	* construct a new message with given type, size
1964	* the new msg has a ref count of 1.
1965	*/
1966	struct ceph_msg *ceph_msg_new2(int type, int front_len, int max_data_items,
1967	gfp_t flags, bool can_fail)
1968	{
1969	struct ceph_msg *m;
1970
1971	m = kmem_cache_zalloc(ceph_msg_cache, flags);
1972	if (m == NULL)
1973	goto out;
1974
1975	m->hdr.type = cpu_to_le16(type);
1976	m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT);
1977	m->hdr.front_len = cpu_to_le32(front_len);
1978
1979	INIT_LIST_HEAD(list: &m->list_head);
1980	kref_init(kref: &m->kref);
1981
1982	/* front */
1983	if (front_len) {
1984	m->front.iov_base = kvmalloc(front_len, flags);
1985	if (m->front.iov_base == NULL) {
1986	dout("ceph_msg_new can't allocate %d bytes\n",
1987	front_len);
1988	goto out2;
1989	}
1990	} else {
1991	m->front.iov_base = NULL;
1992	}
1993	m->front_alloc_len = m->front.iov_len = front_len;
1994
1995	if (max_data_items) {
1996	m->data = kmalloc_array(max_data_items, sizeof(*m->data),
1997	flags);
1998	if (!m->data)
1999	goto out2;
2000
2001	m->max_data_items = max_data_items;
2002	}
2003
2004	dout("ceph_msg_new %p front %d\n", m, front_len);
2005	return m;
2006
2007	out2:
2008	ceph_msg_put(msg: m);
2009	out:
2010	if (!can_fail) {
2011	pr_err("msg_new can't create type %d front %d\n", type,
2012	front_len);
2013	WARN_ON(1);
2014	} else {
2015	dout("msg_new can't create type %d front %d\n", type,
2016	front_len);
2017	}
2018	return NULL;
2019	}
2020	EXPORT_SYMBOL(ceph_msg_new2);
2021
2022	struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
2023	bool can_fail)
2024	{
2025	return ceph_msg_new2(type, front_len, 0, flags, can_fail);
2026	}
2027	EXPORT_SYMBOL(ceph_msg_new);
2028
2029	/*
2030	* Allocate "middle" portion of a message, if it is needed and wasn't
2031	* allocated by alloc_msg. This allows us to read a small fixed-size
2032	* per-type header in the front and then gracefully fail (i.e.,
2033	* propagate the error to the caller based on info in the front) when
2034	* the middle is too large.
2035	*/
2036	static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg)
2037	{
2038	int type = le16_to_cpu(msg->hdr.type);
2039	int middle_len = le32_to_cpu(msg->hdr.middle_len);
2040
2041	dout("alloc_middle %p type %d %s middle_len %d\n", msg, type,
2042	ceph_msg_type_name(type), middle_len);
2043	BUG_ON(!middle_len);
2044	BUG_ON(msg->middle);
2045
2046	msg->middle = ceph_buffer_new(len: middle_len, GFP_NOFS);
2047	if (!msg->middle)
2048	return -ENOMEM;
2049	return 0;
2050	}
2051
2052	/*
2053	* Allocate a message for receiving an incoming message on a
2054	* connection, and save the result in con->in_msg. Uses the
2055	* connection's private alloc_msg op if available.
2056	*
2057	* Returns 0 on success, or a negative error code.
2058	*
2059	* On success, if we set *skip = 1:
2060	* - the next message should be skipped and ignored.
2061	* - con->in_msg == NULL
2062	* or if we set *skip = 0:
2063	* - con->in_msg is non-null.
2064	* On error (ENOMEM, EAGAIN, ...),
2065	* - con->in_msg == NULL
2066	*/
2067	int ceph_con_in_msg_alloc(struct ceph_connection *con,
2068	struct ceph_msg_header *hdr, int *skip)
2069	{
2070	int middle_len = le32_to_cpu(hdr->middle_len);
2071	struct ceph_msg *msg;
2072	int ret = 0;
2073
2074	BUG_ON(con->in_msg != NULL);
2075	BUG_ON(!con->ops->alloc_msg);
2076
2077	mutex_unlock(lock: &con->mutex);
2078	msg = con->ops->alloc_msg(con, hdr, skip);
2079	mutex_lock(&con->mutex);
2080	if (con->state != CEPH_CON_S_OPEN) {
2081	if (msg)
2082	ceph_msg_put(msg);
2083	return -EAGAIN;
2084	}
2085	if (msg) {
2086	BUG_ON(*skip);
2087	msg_con_set(msg, con);
2088	con->in_msg = msg;
2089	} else {
2090	/*
2091	* Null message pointer means either we should skip
2092	* this message or we couldn't allocate memory. The
2093	* former is not an error.
2094	*/
2095	if (*skip)
2096	return 0;
2097
2098	con->error_msg = "error allocating memory for incoming message";
2099	return -ENOMEM;
2100	}
2101	memcpy(&con->in_msg->hdr, hdr, sizeof(*hdr));
2102
2103	if (middle_len && !con->in_msg->middle) {
2104	ret = ceph_alloc_middle(con, msg: con->in_msg);
2105	if (ret < 0) {
2106	ceph_msg_put(msg: con->in_msg);
2107	con->in_msg = NULL;
2108	}
2109	}
2110
2111	return ret;
2112	}
2113
2114	struct ceph_msg *ceph_con_get_out_msg(struct ceph_connection *con)
2115	{
2116	struct ceph_msg *msg;
2117
2118	if (list_empty(head: &con->out_queue))
2119	return NULL;
2120
2121	msg = list_first_entry(&con->out_queue, struct ceph_msg, list_head);
2122	WARN_ON(msg->con != con);
2123
2124	/*
2125	* Put the message on "sent" list using a ref from ceph_con_send().
2126	* It is put when the message is acked or revoked.
2127	*/
2128	list_move_tail(list: &msg->list_head, head: &con->out_sent);
2129
2130	/*
2131	* Only assign outgoing seq # if we haven't sent this message
2132	* yet. If it is requeued, resend with it's original seq.
2133	*/
2134	if (msg->needs_out_seq) {
2135	msg->hdr.seq = cpu_to_le64(++con->out_seq);
2136	msg->needs_out_seq = false;
2137
2138	if (con->ops->reencode_message)
2139	con->ops->reencode_message(msg);
2140	}
2141
2142	/*
2143	* Get a ref for out_msg. It is put when we are done sending the
2144	* message or in case of a fault.
2145	*/
2146	WARN_ON(con->out_msg);
2147	return con->out_msg = ceph_msg_get(msg);
2148	}
2149
2150	/*
2151	* Free a generically kmalloc'd message.
2152	*/
2153	static void ceph_msg_free(struct ceph_msg *m)
2154	{
2155	dout("%s %p\n", __func__, m);
2156	kvfree(addr: m->front.iov_base);
2157	kfree(objp: m->data);
2158	kmem_cache_free(s: ceph_msg_cache, objp: m);
2159	}
2160
2161	static void ceph_msg_release(struct kref *kref)
2162	{
2163	struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
2164	int i;
2165
2166	dout("%s %p\n", __func__, m);
2167	WARN_ON(!list_empty(&m->list_head));
2168
2169	msg_con_set(msg: m, NULL);
2170
2171	/* drop middle, data, if any */
2172	if (m->middle) {
2173	ceph_buffer_put(b: m->middle);
2174	m->middle = NULL;
2175	}
2176
2177	for (i = 0; i < m->num_data_items; i++)
2178	ceph_msg_data_destroy(data: &m->data[i]);
2179
2180	if (m->pool)
2181	ceph_msgpool_put(m->pool, m);
2182	else
2183	ceph_msg_free(m);
2184	}
2185
2186	struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
2187	{
2188	dout("%s %p (was %d)\n", __func__, msg,
2189	kref_read(&msg->kref));
2190	kref_get(kref: &msg->kref);
2191	return msg;
2192	}
2193	EXPORT_SYMBOL(ceph_msg_get);
2194
2195	void ceph_msg_put(struct ceph_msg *msg)
2196	{
2197	dout("%s %p (was %d)\n", __func__, msg,
2198	kref_read(&msg->kref));
2199	kref_put(kref: &msg->kref, release: ceph_msg_release);
2200	}
2201	EXPORT_SYMBOL(ceph_msg_put);
2202
2203	void ceph_msg_dump(struct ceph_msg *msg)
2204	{
2205	pr_debug("msg_dump %p (front_alloc_len %d length %zd)\n", msg,
2206	msg->front_alloc_len, msg->data_length);
2207	print_hex_dump(KERN_DEBUG, prefix_str: "header: ",
2208	prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1,
2209	buf: &msg->hdr, len: sizeof(msg->hdr), ascii: true);
2210	print_hex_dump(KERN_DEBUG, prefix_str: " front: ",
2211	prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1,
2212	buf: msg->front.iov_base, len: msg->front.iov_len, ascii: true);
2213	if (msg->middle)
2214	print_hex_dump(KERN_DEBUG, prefix_str: "middle: ",
2215	prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1,
2216	buf: msg->middle->vec.iov_base,
2217	len: msg->middle->vec.iov_len, ascii: true);
2218	print_hex_dump(KERN_DEBUG, prefix_str: "footer: ",
2219	prefix_type: DUMP_PREFIX_OFFSET, rowsize: 16, groupsize: 1,
2220	buf: &msg->footer, len: sizeof(msg->footer), ascii: true);
2221	}
2222	EXPORT_SYMBOL(ceph_msg_dump);
2223