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