]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blame_incremental - net/ceph/messenger.c
libceph: use local variables for message positions
[mirror_ubuntu-artful-kernel.git] / net / ceph / messenger.c
... / ...
CommitLineData
1#include <linux/ceph/ceph_debug.h>
2
3#include <linux/crc32c.h>
4#include <linux/ctype.h>
5#include <linux/highmem.h>
6#include <linux/inet.h>
7#include <linux/kthread.h>
8#include <linux/net.h>
9#include <linux/slab.h>
10#include <linux/socket.h>
11#include <linux/string.h>
12#ifdef CONFIG_BLOCK
13#include <linux/bio.h>
14#endif /* CONFIG_BLOCK */
15#include <linux/dns_resolver.h>
16#include <net/tcp.h>
17
18#include <linux/ceph/libceph.h>
19#include <linux/ceph/messenger.h>
20#include <linux/ceph/decode.h>
21#include <linux/ceph/pagelist.h>
22#include <linux/export.h>
23
24/*
25 * Ceph uses the messenger to exchange ceph_msg messages with other
26 * hosts in the system. The messenger provides ordered and reliable
27 * delivery. We tolerate TCP disconnects by reconnecting (with
28 * exponential backoff) in the case of a fault (disconnection, bad
29 * crc, protocol error). Acks allow sent messages to be discarded by
30 * the sender.
31 */
32
33/*
34 * We track the state of the socket on a given connection using
35 * values defined below. The transition to a new socket state is
36 * handled by a function which verifies we aren't coming from an
37 * unexpected state.
38 *
39 * --------
40 * | NEW* | transient initial state
41 * --------
42 * | con_sock_state_init()
43 * v
44 * ----------
45 * | CLOSED | initialized, but no socket (and no
46 * ---------- TCP connection)
47 * ^ \
48 * | \ con_sock_state_connecting()
49 * | ----------------------
50 * | \
51 * + con_sock_state_closed() \
52 * |+--------------------------- \
53 * | \ \ \
54 * | ----------- \ \
55 * | | CLOSING | socket event; \ \
56 * | ----------- await close \ \
57 * | ^ \ |
58 * | | \ |
59 * | + con_sock_state_closing() \ |
60 * | / \ | |
61 * | / --------------- | |
62 * | / \ v v
63 * | / --------------
64 * | / -----------------| CONNECTING | socket created, TCP
65 * | | / -------------- connect initiated
66 * | | | con_sock_state_connected()
67 * | | v
68 * -------------
69 * | CONNECTED | TCP connection established
70 * -------------
71 *
72 * State values for ceph_connection->sock_state; NEW is assumed to be 0.
73 */
74
75#define CON_SOCK_STATE_NEW 0 /* -> CLOSED */
76#define CON_SOCK_STATE_CLOSED 1 /* -> CONNECTING */
77#define CON_SOCK_STATE_CONNECTING 2 /* -> CONNECTED or -> CLOSING */
78#define CON_SOCK_STATE_CONNECTED 3 /* -> CLOSING or -> CLOSED */
79#define CON_SOCK_STATE_CLOSING 4 /* -> CLOSED */
80
81/*
82 * connection states
83 */
84#define CON_STATE_CLOSED 1 /* -> PREOPEN */
85#define CON_STATE_PREOPEN 2 /* -> CONNECTING, CLOSED */
86#define CON_STATE_CONNECTING 3 /* -> NEGOTIATING, CLOSED */
87#define CON_STATE_NEGOTIATING 4 /* -> OPEN, CLOSED */
88#define CON_STATE_OPEN 5 /* -> STANDBY, CLOSED */
89#define CON_STATE_STANDBY 6 /* -> PREOPEN, CLOSED */
90
91/*
92 * ceph_connection flag bits
93 */
94#define CON_FLAG_LOSSYTX 0 /* we can close channel or drop
95 * messages on errors */
96#define CON_FLAG_KEEPALIVE_PENDING 1 /* we need to send a keepalive */
97#define CON_FLAG_WRITE_PENDING 2 /* we have data ready to send */
98#define CON_FLAG_SOCK_CLOSED 3 /* socket state changed to closed */
99#define CON_FLAG_BACKOFF 4 /* need to retry queuing delayed work */
100
101static bool con_flag_valid(unsigned long con_flag)
102{
103 switch (con_flag) {
104 case CON_FLAG_LOSSYTX:
105 case CON_FLAG_KEEPALIVE_PENDING:
106 case CON_FLAG_WRITE_PENDING:
107 case CON_FLAG_SOCK_CLOSED:
108 case CON_FLAG_BACKOFF:
109 return true;
110 default:
111 return false;
112 }
113}
114
115static void con_flag_clear(struct ceph_connection *con, unsigned long con_flag)
116{
117 BUG_ON(!con_flag_valid(con_flag));
118
119 clear_bit(con_flag, &con->flags);
120}
121
122static void con_flag_set(struct ceph_connection *con, unsigned long con_flag)
123{
124 BUG_ON(!con_flag_valid(con_flag));
125
126 set_bit(con_flag, &con->flags);
127}
128
129static bool con_flag_test(struct ceph_connection *con, unsigned long con_flag)
130{
131 BUG_ON(!con_flag_valid(con_flag));
132
133 return test_bit(con_flag, &con->flags);
134}
135
136static bool con_flag_test_and_clear(struct ceph_connection *con,
137 unsigned long con_flag)
138{
139 BUG_ON(!con_flag_valid(con_flag));
140
141 return test_and_clear_bit(con_flag, &con->flags);
142}
143
144static bool con_flag_test_and_set(struct ceph_connection *con,
145 unsigned long con_flag)
146{
147 BUG_ON(!con_flag_valid(con_flag));
148
149 return test_and_set_bit(con_flag, &con->flags);
150}
151
152/* static tag bytes (protocol control messages) */
153static char tag_msg = CEPH_MSGR_TAG_MSG;
154static char tag_ack = CEPH_MSGR_TAG_ACK;
155static char tag_keepalive = CEPH_MSGR_TAG_KEEPALIVE;
156
157#ifdef CONFIG_LOCKDEP
158static struct lock_class_key socket_class;
159#endif
160
161/*
162 * When skipping (ignoring) a block of input we read it into a "skip
163 * buffer," which is this many bytes in size.
164 */
165#define SKIP_BUF_SIZE 1024
166
167static void queue_con(struct ceph_connection *con);
168static void con_work(struct work_struct *);
169static void con_fault(struct ceph_connection *con);
170
171/*
172 * Nicely render a sockaddr as a string. An array of formatted
173 * strings is used, to approximate reentrancy.
174 */
175#define ADDR_STR_COUNT_LOG 5 /* log2(# address strings in array) */
176#define ADDR_STR_COUNT (1 << ADDR_STR_COUNT_LOG)
177#define ADDR_STR_COUNT_MASK (ADDR_STR_COUNT - 1)
178#define MAX_ADDR_STR_LEN 64 /* 54 is enough */
179
180static char addr_str[ADDR_STR_COUNT][MAX_ADDR_STR_LEN];
181static atomic_t addr_str_seq = ATOMIC_INIT(0);
182
183static struct page *zero_page; /* used in certain error cases */
184
185const char *ceph_pr_addr(const struct sockaddr_storage *ss)
186{
187 int i;
188 char *s;
189 struct sockaddr_in *in4 = (struct sockaddr_in *) ss;
190 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) ss;
191
192 i = atomic_inc_return(&addr_str_seq) & ADDR_STR_COUNT_MASK;
193 s = addr_str[i];
194
195 switch (ss->ss_family) {
196 case AF_INET:
197 snprintf(s, MAX_ADDR_STR_LEN, "%pI4:%hu", &in4->sin_addr,
198 ntohs(in4->sin_port));
199 break;
200
201 case AF_INET6:
202 snprintf(s, MAX_ADDR_STR_LEN, "[%pI6c]:%hu", &in6->sin6_addr,
203 ntohs(in6->sin6_port));
204 break;
205
206 default:
207 snprintf(s, MAX_ADDR_STR_LEN, "(unknown sockaddr family %hu)",
208 ss->ss_family);
209 }
210
211 return s;
212}
213EXPORT_SYMBOL(ceph_pr_addr);
214
215static void encode_my_addr(struct ceph_messenger *msgr)
216{
217 memcpy(&msgr->my_enc_addr, &msgr->inst.addr, sizeof(msgr->my_enc_addr));
218 ceph_encode_addr(&msgr->my_enc_addr);
219}
220
221/*
222 * work queue for all reading and writing to/from the socket.
223 */
224static struct workqueue_struct *ceph_msgr_wq;
225
226static void _ceph_msgr_exit(void)
227{
228 if (ceph_msgr_wq) {
229 destroy_workqueue(ceph_msgr_wq);
230 ceph_msgr_wq = NULL;
231 }
232
233 BUG_ON(zero_page == NULL);
234 kunmap(zero_page);
235 page_cache_release(zero_page);
236 zero_page = NULL;
237}
238
239int ceph_msgr_init(void)
240{
241 BUG_ON(zero_page != NULL);
242 zero_page = ZERO_PAGE(0);
243 page_cache_get(zero_page);
244
245 ceph_msgr_wq = alloc_workqueue("ceph-msgr", WQ_NON_REENTRANT, 0);
246 if (ceph_msgr_wq)
247 return 0;
248
249 pr_err("msgr_init failed to create workqueue\n");
250 _ceph_msgr_exit();
251
252 return -ENOMEM;
253}
254EXPORT_SYMBOL(ceph_msgr_init);
255
256void ceph_msgr_exit(void)
257{
258 BUG_ON(ceph_msgr_wq == NULL);
259
260 _ceph_msgr_exit();
261}
262EXPORT_SYMBOL(ceph_msgr_exit);
263
264void ceph_msgr_flush(void)
265{
266 flush_workqueue(ceph_msgr_wq);
267}
268EXPORT_SYMBOL(ceph_msgr_flush);
269
270/* Connection socket state transition functions */
271
272static void con_sock_state_init(struct ceph_connection *con)
273{
274 int old_state;
275
276 old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CLOSED);
277 if (WARN_ON(old_state != CON_SOCK_STATE_NEW))
278 printk("%s: unexpected old state %d\n", __func__, old_state);
279 dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
280 CON_SOCK_STATE_CLOSED);
281}
282
283static void con_sock_state_connecting(struct ceph_connection *con)
284{
285 int old_state;
286
287 old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CONNECTING);
288 if (WARN_ON(old_state != CON_SOCK_STATE_CLOSED))
289 printk("%s: unexpected old state %d\n", __func__, old_state);
290 dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
291 CON_SOCK_STATE_CONNECTING);
292}
293
294static void con_sock_state_connected(struct ceph_connection *con)
295{
296 int old_state;
297
298 old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CONNECTED);
299 if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTING))
300 printk("%s: unexpected old state %d\n", __func__, old_state);
301 dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
302 CON_SOCK_STATE_CONNECTED);
303}
304
305static void con_sock_state_closing(struct ceph_connection *con)
306{
307 int old_state;
308
309 old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CLOSING);
310 if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTING &&
311 old_state != CON_SOCK_STATE_CONNECTED &&
312 old_state != CON_SOCK_STATE_CLOSING))
313 printk("%s: unexpected old state %d\n", __func__, old_state);
314 dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
315 CON_SOCK_STATE_CLOSING);
316}
317
318static void con_sock_state_closed(struct ceph_connection *con)
319{
320 int old_state;
321
322 old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CLOSED);
323 if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTED &&
324 old_state != CON_SOCK_STATE_CLOSING &&
325 old_state != CON_SOCK_STATE_CONNECTING &&
326 old_state != CON_SOCK_STATE_CLOSED))
327 printk("%s: unexpected old state %d\n", __func__, old_state);
328 dout("%s con %p sock %d -> %d\n", __func__, con, old_state,
329 CON_SOCK_STATE_CLOSED);
330}
331
332/*
333 * socket callback functions
334 */
335
336/* data available on socket, or listen socket received a connect */
337static void ceph_sock_data_ready(struct sock *sk, int count_unused)
338{
339 struct ceph_connection *con = sk->sk_user_data;
340 if (atomic_read(&con->msgr->stopping)) {
341 return;
342 }
343
344 if (sk->sk_state != TCP_CLOSE_WAIT) {
345 dout("%s on %p state = %lu, queueing work\n", __func__,
346 con, con->state);
347 queue_con(con);
348 }
349}
350
351/* socket has buffer space for writing */
352static void ceph_sock_write_space(struct sock *sk)
353{
354 struct ceph_connection *con = sk->sk_user_data;
355
356 /* only queue to workqueue if there is data we want to write,
357 * and there is sufficient space in the socket buffer to accept
358 * more data. clear SOCK_NOSPACE so that ceph_sock_write_space()
359 * doesn't get called again until try_write() fills the socket
360 * buffer. See net/ipv4/tcp_input.c:tcp_check_space()
361 * and net/core/stream.c:sk_stream_write_space().
362 */
363 if (con_flag_test(con, CON_FLAG_WRITE_PENDING)) {
364 if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
365 dout("%s %p queueing write work\n", __func__, con);
366 clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
367 queue_con(con);
368 }
369 } else {
370 dout("%s %p nothing to write\n", __func__, con);
371 }
372}
373
374/* socket's state has changed */
375static void ceph_sock_state_change(struct sock *sk)
376{
377 struct ceph_connection *con = sk->sk_user_data;
378
379 dout("%s %p state = %lu sk_state = %u\n", __func__,
380 con, con->state, sk->sk_state);
381
382 switch (sk->sk_state) {
383 case TCP_CLOSE:
384 dout("%s TCP_CLOSE\n", __func__);
385 case TCP_CLOSE_WAIT:
386 dout("%s TCP_CLOSE_WAIT\n", __func__);
387 con_sock_state_closing(con);
388 con_flag_set(con, CON_FLAG_SOCK_CLOSED);
389 queue_con(con);
390 break;
391 case TCP_ESTABLISHED:
392 dout("%s TCP_ESTABLISHED\n", __func__);
393 con_sock_state_connected(con);
394 queue_con(con);
395 break;
396 default: /* Everything else is uninteresting */
397 break;
398 }
399}
400
401/*
402 * set up socket callbacks
403 */
404static void set_sock_callbacks(struct socket *sock,
405 struct ceph_connection *con)
406{
407 struct sock *sk = sock->sk;
408 sk->sk_user_data = con;
409 sk->sk_data_ready = ceph_sock_data_ready;
410 sk->sk_write_space = ceph_sock_write_space;
411 sk->sk_state_change = ceph_sock_state_change;
412}
413
414
415/*
416 * socket helpers
417 */
418
419/*
420 * initiate connection to a remote socket.
421 */
422static int ceph_tcp_connect(struct ceph_connection *con)
423{
424 struct sockaddr_storage *paddr = &con->peer_addr.in_addr;
425 struct socket *sock;
426 int ret;
427
428 BUG_ON(con->sock);
429 ret = sock_create_kern(con->peer_addr.in_addr.ss_family, SOCK_STREAM,
430 IPPROTO_TCP, &sock);
431 if (ret)
432 return ret;
433 sock->sk->sk_allocation = GFP_NOFS;
434
435#ifdef CONFIG_LOCKDEP
436 lockdep_set_class(&sock->sk->sk_lock, &socket_class);
437#endif
438
439 set_sock_callbacks(sock, con);
440
441 dout("connect %s\n", ceph_pr_addr(&con->peer_addr.in_addr));
442
443 con_sock_state_connecting(con);
444 ret = sock->ops->connect(sock, (struct sockaddr *)paddr, sizeof(*paddr),
445 O_NONBLOCK);
446 if (ret == -EINPROGRESS) {
447 dout("connect %s EINPROGRESS sk_state = %u\n",
448 ceph_pr_addr(&con->peer_addr.in_addr),
449 sock->sk->sk_state);
450 } else if (ret < 0) {
451 pr_err("connect %s error %d\n",
452 ceph_pr_addr(&con->peer_addr.in_addr), ret);
453 sock_release(sock);
454 con->error_msg = "connect error";
455
456 return ret;
457 }
458 con->sock = sock;
459 return 0;
460}
461
462static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
463{
464 struct kvec iov = {buf, len};
465 struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
466 int r;
467
468 r = kernel_recvmsg(sock, &msg, &iov, 1, len, msg.msg_flags);
469 if (r == -EAGAIN)
470 r = 0;
471 return r;
472}
473
474/*
475 * write something. @more is true if caller will be sending more data
476 * shortly.
477 */
478static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov,
479 size_t kvlen, size_t len, int more)
480{
481 struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
482 int r;
483
484 if (more)
485 msg.msg_flags |= MSG_MORE;
486 else
487 msg.msg_flags |= MSG_EOR; /* superfluous, but what the hell */
488
489 r = kernel_sendmsg(sock, &msg, iov, kvlen, len);
490 if (r == -EAGAIN)
491 r = 0;
492 return r;
493}
494
495static int ceph_tcp_sendpage(struct socket *sock, struct page *page,
496 int offset, size_t size, bool more)
497{
498 int flags = MSG_DONTWAIT | MSG_NOSIGNAL | (more ? MSG_MORE : MSG_EOR);
499 int ret;
500
501 ret = kernel_sendpage(sock, page, offset, size, flags);
502 if (ret == -EAGAIN)
503 ret = 0;
504
505 return ret;
506}
507
508
509/*
510 * Shutdown/close the socket for the given connection.
511 */
512static int con_close_socket(struct ceph_connection *con)
513{
514 int rc = 0;
515
516 dout("con_close_socket on %p sock %p\n", con, con->sock);
517 if (con->sock) {
518 rc = con->sock->ops->shutdown(con->sock, SHUT_RDWR);
519 sock_release(con->sock);
520 con->sock = NULL;
521 }
522
523 /*
524 * Forcibly clear the SOCK_CLOSED flag. It gets set
525 * independent of the connection mutex, and we could have
526 * received a socket close event before we had the chance to
527 * shut the socket down.
528 */
529 con_flag_clear(con, CON_FLAG_SOCK_CLOSED);
530
531 con_sock_state_closed(con);
532 return rc;
533}
534
535/*
536 * Reset a connection. Discard all incoming and outgoing messages
537 * and clear *_seq state.
538 */
539static void ceph_msg_remove(struct ceph_msg *msg)
540{
541 list_del_init(&msg->list_head);
542 BUG_ON(msg->con == NULL);
543 msg->con->ops->put(msg->con);
544 msg->con = NULL;
545
546 ceph_msg_put(msg);
547}
548static void ceph_msg_remove_list(struct list_head *head)
549{
550 while (!list_empty(head)) {
551 struct ceph_msg *msg = list_first_entry(head, struct ceph_msg,
552 list_head);
553 ceph_msg_remove(msg);
554 }
555}
556
557static void reset_connection(struct ceph_connection *con)
558{
559 /* reset connection, out_queue, msg_ and connect_seq */
560 /* discard existing out_queue and msg_seq */
561 dout("reset_connection %p\n", con);
562 ceph_msg_remove_list(&con->out_queue);
563 ceph_msg_remove_list(&con->out_sent);
564
565 if (con->in_msg) {
566 BUG_ON(con->in_msg->con != con);
567 con->in_msg->con = NULL;
568 ceph_msg_put(con->in_msg);
569 con->in_msg = NULL;
570 con->ops->put(con);
571 }
572
573 con->connect_seq = 0;
574 con->out_seq = 0;
575 if (con->out_msg) {
576 ceph_msg_put(con->out_msg);
577 con->out_msg = NULL;
578 }
579 con->in_seq = 0;
580 con->in_seq_acked = 0;
581}
582
583/*
584 * mark a peer down. drop any open connections.
585 */
586void ceph_con_close(struct ceph_connection *con)
587{
588 mutex_lock(&con->mutex);
589 dout("con_close %p peer %s\n", con,
590 ceph_pr_addr(&con->peer_addr.in_addr));
591 con->state = CON_STATE_CLOSED;
592
593 con_flag_clear(con, CON_FLAG_LOSSYTX); /* so we retry next connect */
594 con_flag_clear(con, CON_FLAG_KEEPALIVE_PENDING);
595 con_flag_clear(con, CON_FLAG_WRITE_PENDING);
596 con_flag_clear(con, CON_FLAG_BACKOFF);
597
598 reset_connection(con);
599 con->peer_global_seq = 0;
600 cancel_delayed_work(&con->work);
601 con_close_socket(con);
602 mutex_unlock(&con->mutex);
603}
604EXPORT_SYMBOL(ceph_con_close);
605
606/*
607 * Reopen a closed connection, with a new peer address.
608 */
609void ceph_con_open(struct ceph_connection *con,
610 __u8 entity_type, __u64 entity_num,
611 struct ceph_entity_addr *addr)
612{
613 mutex_lock(&con->mutex);
614 dout("con_open %p %s\n", con, ceph_pr_addr(&addr->in_addr));
615
616 WARN_ON(con->state != CON_STATE_CLOSED);
617 con->state = CON_STATE_PREOPEN;
618
619 con->peer_name.type = (__u8) entity_type;
620 con->peer_name.num = cpu_to_le64(entity_num);
621
622 memcpy(&con->peer_addr, addr, sizeof(*addr));
623 con->delay = 0; /* reset backoff memory */
624 mutex_unlock(&con->mutex);
625 queue_con(con);
626}
627EXPORT_SYMBOL(ceph_con_open);
628
629/*
630 * return true if this connection ever successfully opened
631 */
632bool ceph_con_opened(struct ceph_connection *con)
633{
634 return con->connect_seq > 0;
635}
636
637/*
638 * initialize a new connection.
639 */
640void ceph_con_init(struct ceph_connection *con, void *private,
641 const struct ceph_connection_operations *ops,
642 struct ceph_messenger *msgr)
643{
644 dout("con_init %p\n", con);
645 memset(con, 0, sizeof(*con));
646 con->private = private;
647 con->ops = ops;
648 con->msgr = msgr;
649
650 con_sock_state_init(con);
651
652 mutex_init(&con->mutex);
653 INIT_LIST_HEAD(&con->out_queue);
654 INIT_LIST_HEAD(&con->out_sent);
655 INIT_DELAYED_WORK(&con->work, con_work);
656
657 con->state = CON_STATE_CLOSED;
658}
659EXPORT_SYMBOL(ceph_con_init);
660
661
662/*
663 * We maintain a global counter to order connection attempts. Get
664 * a unique seq greater than @gt.
665 */
666static u32 get_global_seq(struct ceph_messenger *msgr, u32 gt)
667{
668 u32 ret;
669
670 spin_lock(&msgr->global_seq_lock);
671 if (msgr->global_seq < gt)
672 msgr->global_seq = gt;
673 ret = ++msgr->global_seq;
674 spin_unlock(&msgr->global_seq_lock);
675 return ret;
676}
677
678static void con_out_kvec_reset(struct ceph_connection *con)
679{
680 con->out_kvec_left = 0;
681 con->out_kvec_bytes = 0;
682 con->out_kvec_cur = &con->out_kvec[0];
683}
684
685static void con_out_kvec_add(struct ceph_connection *con,
686 size_t size, void *data)
687{
688 int index;
689
690 index = con->out_kvec_left;
691 BUG_ON(index >= ARRAY_SIZE(con->out_kvec));
692
693 con->out_kvec[index].iov_len = size;
694 con->out_kvec[index].iov_base = data;
695 con->out_kvec_left++;
696 con->out_kvec_bytes += size;
697}
698
699#ifdef CONFIG_BLOCK
700static void init_bio_iter(struct bio *bio, struct bio **bio_iter,
701 unsigned int *bio_seg)
702{
703 if (!bio) {
704 *bio_iter = NULL;
705 *bio_seg = 0;
706 return;
707 }
708 *bio_iter = bio;
709 *bio_seg = (unsigned int) bio->bi_idx;
710}
711
712static void iter_bio_next(struct bio **bio_iter, unsigned int *seg)
713{
714 if (*bio_iter == NULL)
715 return;
716
717 BUG_ON(*seg >= (*bio_iter)->bi_vcnt);
718
719 (*seg)++;
720 if (*seg == (*bio_iter)->bi_vcnt)
721 init_bio_iter((*bio_iter)->bi_next, bio_iter, seg);
722}
723#endif
724
725static void prepare_write_message_data(struct ceph_connection *con)
726{
727 struct ceph_msg *msg = con->out_msg;
728 struct ceph_msg_pos *msg_pos = &con->out_msg_pos;
729
730 BUG_ON(!msg);
731 BUG_ON(!msg->hdr.data_len);
732
733 /* initialize page iterator */
734 msg_pos->page = 0;
735 if (msg->pages)
736 msg_pos->page_pos = msg->page_alignment;
737 else
738 msg_pos->page_pos = 0;
739#ifdef CONFIG_BLOCK
740 if (msg->bio)
741 init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
742#endif
743 msg_pos->data_pos = 0;
744 msg_pos->did_page_crc = false;
745 con->out_more = 1; /* data + footer will follow */
746}
747
748/*
749 * Prepare footer for currently outgoing message, and finish things
750 * off. Assumes out_kvec* are already valid.. we just add on to the end.
751 */
752static void prepare_write_message_footer(struct ceph_connection *con)
753{
754 struct ceph_msg *m = con->out_msg;
755 int v = con->out_kvec_left;
756
757 m->footer.flags |= CEPH_MSG_FOOTER_COMPLETE;
758
759 dout("prepare_write_message_footer %p\n", con);
760 con->out_kvec_is_msg = true;
761 con->out_kvec[v].iov_base = &m->footer;
762 con->out_kvec[v].iov_len = sizeof(m->footer);
763 con->out_kvec_bytes += sizeof(m->footer);
764 con->out_kvec_left++;
765 con->out_more = m->more_to_follow;
766 con->out_msg_done = true;
767}
768
769/*
770 * Prepare headers for the next outgoing message.
771 */
772static void prepare_write_message(struct ceph_connection *con)
773{
774 struct ceph_msg *m;
775 u32 crc;
776
777 con_out_kvec_reset(con);
778 con->out_kvec_is_msg = true;
779 con->out_msg_done = false;
780
781 /* Sneak an ack in there first? If we can get it into the same
782 * TCP packet that's a good thing. */
783 if (con->in_seq > con->in_seq_acked) {
784 con->in_seq_acked = con->in_seq;
785 con_out_kvec_add(con, sizeof (tag_ack), &tag_ack);
786 con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
787 con_out_kvec_add(con, sizeof (con->out_temp_ack),
788 &con->out_temp_ack);
789 }
790
791 BUG_ON(list_empty(&con->out_queue));
792 m = list_first_entry(&con->out_queue, struct ceph_msg, list_head);
793 con->out_msg = m;
794 BUG_ON(m->con != con);
795
796 /* put message on sent list */
797 ceph_msg_get(m);
798 list_move_tail(&m->list_head, &con->out_sent);
799
800 /*
801 * only assign outgoing seq # if we haven't sent this message
802 * yet. if it is requeued, resend with it's original seq.
803 */
804 if (m->needs_out_seq) {
805 m->hdr.seq = cpu_to_le64(++con->out_seq);
806 m->needs_out_seq = false;
807 }
808
809 dout("prepare_write_message %p seq %lld type %d len %d+%d+%d (%zd)\n",
810 m, con->out_seq, le16_to_cpu(m->hdr.type),
811 le32_to_cpu(m->hdr.front_len), le32_to_cpu(m->hdr.middle_len),
812 le32_to_cpu(m->hdr.data_len), m->length);
813 BUG_ON(le32_to_cpu(m->hdr.front_len) != m->front.iov_len);
814
815 /* tag + hdr + front + middle */
816 con_out_kvec_add(con, sizeof (tag_msg), &tag_msg);
817 con_out_kvec_add(con, sizeof (m->hdr), &m->hdr);
818 con_out_kvec_add(con, m->front.iov_len, m->front.iov_base);
819
820 if (m->middle)
821 con_out_kvec_add(con, m->middle->vec.iov_len,
822 m->middle->vec.iov_base);
823
824 /* fill in crc (except data pages), footer */
825 crc = crc32c(0, &m->hdr, offsetof(struct ceph_msg_header, crc));
826 con->out_msg->hdr.crc = cpu_to_le32(crc);
827 con->out_msg->footer.flags = 0;
828
829 crc = crc32c(0, m->front.iov_base, m->front.iov_len);
830 con->out_msg->footer.front_crc = cpu_to_le32(crc);
831 if (m->middle) {
832 crc = crc32c(0, m->middle->vec.iov_base,
833 m->middle->vec.iov_len);
834 con->out_msg->footer.middle_crc = cpu_to_le32(crc);
835 } else
836 con->out_msg->footer.middle_crc = 0;
837 dout("%s front_crc %u middle_crc %u\n", __func__,
838 le32_to_cpu(con->out_msg->footer.front_crc),
839 le32_to_cpu(con->out_msg->footer.middle_crc));
840
841 /* is there a data payload? */
842 con->out_msg->footer.data_crc = 0;
843 if (m->hdr.data_len)
844 prepare_write_message_data(con);
845 else
846 /* no, queue up footer too and be done */
847 prepare_write_message_footer(con);
848
849 con_flag_set(con, CON_FLAG_WRITE_PENDING);
850}
851
852/*
853 * Prepare an ack.
854 */
855static void prepare_write_ack(struct ceph_connection *con)
856{
857 dout("prepare_write_ack %p %llu -> %llu\n", con,
858 con->in_seq_acked, con->in_seq);
859 con->in_seq_acked = con->in_seq;
860
861 con_out_kvec_reset(con);
862
863 con_out_kvec_add(con, sizeof (tag_ack), &tag_ack);
864
865 con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
866 con_out_kvec_add(con, sizeof (con->out_temp_ack),
867 &con->out_temp_ack);
868
869 con->out_more = 1; /* more will follow.. eventually.. */
870 con_flag_set(con, CON_FLAG_WRITE_PENDING);
871}
872
873/*
874 * Prepare to write keepalive byte.
875 */
876static void prepare_write_keepalive(struct ceph_connection *con)
877{
878 dout("prepare_write_keepalive %p\n", con);
879 con_out_kvec_reset(con);
880 con_out_kvec_add(con, sizeof (tag_keepalive), &tag_keepalive);
881 con_flag_set(con, CON_FLAG_WRITE_PENDING);
882}
883
884/*
885 * Connection negotiation.
886 */
887
888static struct ceph_auth_handshake *get_connect_authorizer(struct ceph_connection *con,
889 int *auth_proto)
890{
891 struct ceph_auth_handshake *auth;
892
893 if (!con->ops->get_authorizer) {
894 con->out_connect.authorizer_protocol = CEPH_AUTH_UNKNOWN;
895 con->out_connect.authorizer_len = 0;
896 return NULL;
897 }
898
899 /* Can't hold the mutex while getting authorizer */
900 mutex_unlock(&con->mutex);
901 auth = con->ops->get_authorizer(con, auth_proto, con->auth_retry);
902 mutex_lock(&con->mutex);
903
904 if (IS_ERR(auth))
905 return auth;
906 if (con->state != CON_STATE_NEGOTIATING)
907 return ERR_PTR(-EAGAIN);
908
909 con->auth_reply_buf = auth->authorizer_reply_buf;
910 con->auth_reply_buf_len = auth->authorizer_reply_buf_len;
911 return auth;
912}
913
914/*
915 * We connected to a peer and are saying hello.
916 */
917static void prepare_write_banner(struct ceph_connection *con)
918{
919 con_out_kvec_add(con, strlen(CEPH_BANNER), CEPH_BANNER);
920 con_out_kvec_add(con, sizeof (con->msgr->my_enc_addr),
921 &con->msgr->my_enc_addr);
922
923 con->out_more = 0;
924 con_flag_set(con, CON_FLAG_WRITE_PENDING);
925}
926
927static int prepare_write_connect(struct ceph_connection *con)
928{
929 unsigned int global_seq = get_global_seq(con->msgr, 0);
930 int proto;
931 int auth_proto;
932 struct ceph_auth_handshake *auth;
933
934 switch (con->peer_name.type) {
935 case CEPH_ENTITY_TYPE_MON:
936 proto = CEPH_MONC_PROTOCOL;
937 break;
938 case CEPH_ENTITY_TYPE_OSD:
939 proto = CEPH_OSDC_PROTOCOL;
940 break;
941 case CEPH_ENTITY_TYPE_MDS:
942 proto = CEPH_MDSC_PROTOCOL;
943 break;
944 default:
945 BUG();
946 }
947
948 dout("prepare_write_connect %p cseq=%d gseq=%d proto=%d\n", con,
949 con->connect_seq, global_seq, proto);
950
951 con->out_connect.features = cpu_to_le64(con->msgr->supported_features);
952 con->out_connect.host_type = cpu_to_le32(CEPH_ENTITY_TYPE_CLIENT);
953 con->out_connect.connect_seq = cpu_to_le32(con->connect_seq);
954 con->out_connect.global_seq = cpu_to_le32(global_seq);
955 con->out_connect.protocol_version = cpu_to_le32(proto);
956 con->out_connect.flags = 0;
957
958 auth_proto = CEPH_AUTH_UNKNOWN;
959 auth = get_connect_authorizer(con, &auth_proto);
960 if (IS_ERR(auth))
961 return PTR_ERR(auth);
962
963 con->out_connect.authorizer_protocol = cpu_to_le32(auth_proto);
964 con->out_connect.authorizer_len = auth ?
965 cpu_to_le32(auth->authorizer_buf_len) : 0;
966
967 con_out_kvec_add(con, sizeof (con->out_connect),
968 &con->out_connect);
969 if (auth && auth->authorizer_buf_len)
970 con_out_kvec_add(con, auth->authorizer_buf_len,
971 auth->authorizer_buf);
972
973 con->out_more = 0;
974 con_flag_set(con, CON_FLAG_WRITE_PENDING);
975
976 return 0;
977}
978
979/*
980 * write as much of pending kvecs to the socket as we can.
981 * 1 -> done
982 * 0 -> socket full, but more to do
983 * <0 -> error
984 */
985static int write_partial_kvec(struct ceph_connection *con)
986{
987 int ret;
988
989 dout("write_partial_kvec %p %d left\n", con, con->out_kvec_bytes);
990 while (con->out_kvec_bytes > 0) {
991 ret = ceph_tcp_sendmsg(con->sock, con->out_kvec_cur,
992 con->out_kvec_left, con->out_kvec_bytes,
993 con->out_more);
994 if (ret <= 0)
995 goto out;
996 con->out_kvec_bytes -= ret;
997 if (con->out_kvec_bytes == 0)
998 break; /* done */
999
1000 /* account for full iov entries consumed */
1001 while (ret >= con->out_kvec_cur->iov_len) {
1002 BUG_ON(!con->out_kvec_left);
1003 ret -= con->out_kvec_cur->iov_len;
1004 con->out_kvec_cur++;
1005 con->out_kvec_left--;
1006 }
1007 /* and for a partially-consumed entry */
1008 if (ret) {
1009 con->out_kvec_cur->iov_len -= ret;
1010 con->out_kvec_cur->iov_base += ret;
1011 }
1012 }
1013 con->out_kvec_left = 0;
1014 con->out_kvec_is_msg = false;
1015 ret = 1;
1016out:
1017 dout("write_partial_kvec %p %d left in %d kvecs ret = %d\n", con,
1018 con->out_kvec_bytes, con->out_kvec_left, ret);
1019 return ret; /* done! */
1020}
1021
1022static void out_msg_pos_next(struct ceph_connection *con, struct page *page,
1023 size_t len, size_t sent, bool in_trail)
1024{
1025 struct ceph_msg *msg = con->out_msg;
1026 struct ceph_msg_pos *msg_pos = &con->out_msg_pos;
1027
1028 BUG_ON(!msg);
1029 BUG_ON(!sent);
1030
1031 msg_pos->data_pos += sent;
1032 msg_pos->page_pos += sent;
1033 if (sent < len)
1034 return;
1035
1036 BUG_ON(sent != len);
1037 msg_pos->page_pos = 0;
1038 msg_pos->page++;
1039 msg_pos->did_page_crc = false;
1040 if (in_trail)
1041 list_rotate_left(&msg->trail->head);
1042 else if (msg->pagelist)
1043 list_rotate_left(&msg->pagelist->head);
1044#ifdef CONFIG_BLOCK
1045 else if (msg->bio)
1046 iter_bio_next(&msg->bio_iter, &msg->bio_seg);
1047#endif
1048}
1049
1050static void in_msg_pos_next(struct ceph_connection *con, size_t len,
1051 size_t received)
1052{
1053 struct ceph_msg *msg = con->in_msg;
1054 struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
1055
1056 BUG_ON(!msg);
1057 BUG_ON(!received);
1058
1059 msg_pos->data_pos += received;
1060 msg_pos->page_pos += received;
1061 if (received < len)
1062 return;
1063
1064 BUG_ON(received != len);
1065 msg_pos->page_pos = 0;
1066 msg_pos->page++;
1067#ifdef CONFIG_BLOCK
1068 if (msg->bio)
1069 iter_bio_next(&msg->bio_iter, &msg->bio_seg);
1070#endif /* CONFIG_BLOCK */
1071}
1072
1073/*
1074 * Write as much message data payload as we can. If we finish, queue
1075 * up the footer.
1076 * 1 -> done, footer is now queued in out_kvec[].
1077 * 0 -> socket full, but more to do
1078 * <0 -> error
1079 */
1080static int write_partial_msg_pages(struct ceph_connection *con)
1081{
1082 struct ceph_msg *msg = con->out_msg;
1083 struct ceph_msg_pos *msg_pos = &con->out_msg_pos;
1084 unsigned int data_len = le32_to_cpu(msg->hdr.data_len);
1085 size_t len;
1086 bool do_datacrc = !con->msgr->nocrc;
1087 int ret;
1088 int total_max_write;
1089 bool in_trail = false;
1090 const size_t trail_len = (msg->trail ? msg->trail->length : 0);
1091 const size_t trail_off = data_len - trail_len;
1092
1093 dout("write_partial_msg_pages %p msg %p page %d offset %d\n",
1094 con, msg, msg_pos->page, msg_pos->page_pos);
1095
1096 /*
1097 * Iterate through each page that contains data to be
1098 * written, and send as much as possible for each.
1099 *
1100 * If we are calculating the data crc (the default), we will
1101 * need to map the page. If we have no pages, they have
1102 * been revoked, so use the zero page.
1103 */
1104 while (data_len > msg_pos->data_pos) {
1105 struct page *page = NULL;
1106 int max_write = PAGE_SIZE;
1107 int bio_offset = 0;
1108
1109 in_trail = in_trail || msg_pos->data_pos >= trail_off;
1110 if (!in_trail)
1111 total_max_write = trail_off - msg_pos->data_pos;
1112
1113 if (in_trail) {
1114 total_max_write = data_len - msg_pos->data_pos;
1115
1116 page = list_first_entry(&msg->trail->head,
1117 struct page, lru);
1118 } else if (msg->pages) {
1119 page = msg->pages[msg_pos->page];
1120 } else if (msg->pagelist) {
1121 page = list_first_entry(&msg->pagelist->head,
1122 struct page, lru);
1123#ifdef CONFIG_BLOCK
1124 } else if (msg->bio) {
1125 struct bio_vec *bv;
1126
1127 bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
1128 page = bv->bv_page;
1129 bio_offset = bv->bv_offset;
1130 max_write = bv->bv_len;
1131#endif
1132 } else {
1133 page = zero_page;
1134 }
1135 len = min_t(int, max_write - msg_pos->page_pos,
1136 total_max_write);
1137
1138 if (do_datacrc && !msg_pos->did_page_crc) {
1139 void *base;
1140 u32 crc = le32_to_cpu(msg->footer.data_crc);
1141 char *kaddr;
1142
1143 kaddr = kmap(page);
1144 BUG_ON(kaddr == NULL);
1145 base = kaddr + msg_pos->page_pos + bio_offset;
1146 crc = crc32c(crc, base, len);
1147 kunmap(page);
1148 msg->footer.data_crc = cpu_to_le32(crc);
1149 msg_pos->did_page_crc = true;
1150 }
1151 ret = ceph_tcp_sendpage(con->sock, page,
1152 msg_pos->page_pos + bio_offset,
1153 len, true);
1154 if (ret <= 0)
1155 goto out;
1156
1157 out_msg_pos_next(con, page, len, (size_t) ret, in_trail);
1158 }
1159
1160 dout("write_partial_msg_pages %p msg %p done\n", con, msg);
1161
1162 /* prepare and queue up footer, too */
1163 if (!do_datacrc)
1164 msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
1165 con_out_kvec_reset(con);
1166 prepare_write_message_footer(con);
1167 ret = 1;
1168out:
1169 return ret;
1170}
1171
1172/*
1173 * write some zeros
1174 */
1175static int write_partial_skip(struct ceph_connection *con)
1176{
1177 int ret;
1178
1179 while (con->out_skip > 0) {
1180 size_t size = min(con->out_skip, (int) PAGE_CACHE_SIZE);
1181
1182 ret = ceph_tcp_sendpage(con->sock, zero_page, 0, size, true);
1183 if (ret <= 0)
1184 goto out;
1185 con->out_skip -= ret;
1186 }
1187 ret = 1;
1188out:
1189 return ret;
1190}
1191
1192/*
1193 * Prepare to read connection handshake, or an ack.
1194 */
1195static void prepare_read_banner(struct ceph_connection *con)
1196{
1197 dout("prepare_read_banner %p\n", con);
1198 con->in_base_pos = 0;
1199}
1200
1201static void prepare_read_connect(struct ceph_connection *con)
1202{
1203 dout("prepare_read_connect %p\n", con);
1204 con->in_base_pos = 0;
1205}
1206
1207static void prepare_read_ack(struct ceph_connection *con)
1208{
1209 dout("prepare_read_ack %p\n", con);
1210 con->in_base_pos = 0;
1211}
1212
1213static void prepare_read_tag(struct ceph_connection *con)
1214{
1215 dout("prepare_read_tag %p\n", con);
1216 con->in_base_pos = 0;
1217 con->in_tag = CEPH_MSGR_TAG_READY;
1218}
1219
1220/*
1221 * Prepare to read a message.
1222 */
1223static int prepare_read_message(struct ceph_connection *con)
1224{
1225 dout("prepare_read_message %p\n", con);
1226 BUG_ON(con->in_msg != NULL);
1227 con->in_base_pos = 0;
1228 con->in_front_crc = con->in_middle_crc = con->in_data_crc = 0;
1229 return 0;
1230}
1231
1232
1233static int read_partial(struct ceph_connection *con,
1234 int end, int size, void *object)
1235{
1236 while (con->in_base_pos < end) {
1237 int left = end - con->in_base_pos;
1238 int have = size - left;
1239 int ret = ceph_tcp_recvmsg(con->sock, object + have, left);
1240 if (ret <= 0)
1241 return ret;
1242 con->in_base_pos += ret;
1243 }
1244 return 1;
1245}
1246
1247
1248/*
1249 * Read all or part of the connect-side handshake on a new connection
1250 */
1251static int read_partial_banner(struct ceph_connection *con)
1252{
1253 int size;
1254 int end;
1255 int ret;
1256
1257 dout("read_partial_banner %p at %d\n", con, con->in_base_pos);
1258
1259 /* peer's banner */
1260 size = strlen(CEPH_BANNER);
1261 end = size;
1262 ret = read_partial(con, end, size, con->in_banner);
1263 if (ret <= 0)
1264 goto out;
1265
1266 size = sizeof (con->actual_peer_addr);
1267 end += size;
1268 ret = read_partial(con, end, size, &con->actual_peer_addr);
1269 if (ret <= 0)
1270 goto out;
1271
1272 size = sizeof (con->peer_addr_for_me);
1273 end += size;
1274 ret = read_partial(con, end, size, &con->peer_addr_for_me);
1275 if (ret <= 0)
1276 goto out;
1277
1278out:
1279 return ret;
1280}
1281
1282static int read_partial_connect(struct ceph_connection *con)
1283{
1284 int size;
1285 int end;
1286 int ret;
1287
1288 dout("read_partial_connect %p at %d\n", con, con->in_base_pos);
1289
1290 size = sizeof (con->in_reply);
1291 end = size;
1292 ret = read_partial(con, end, size, &con->in_reply);
1293 if (ret <= 0)
1294 goto out;
1295
1296 size = le32_to_cpu(con->in_reply.authorizer_len);
1297 end += size;
1298 ret = read_partial(con, end, size, con->auth_reply_buf);
1299 if (ret <= 0)
1300 goto out;
1301
1302 dout("read_partial_connect %p tag %d, con_seq = %u, g_seq = %u\n",
1303 con, (int)con->in_reply.tag,
1304 le32_to_cpu(con->in_reply.connect_seq),
1305 le32_to_cpu(con->in_reply.global_seq));
1306out:
1307 return ret;
1308
1309}
1310
1311/*
1312 * Verify the hello banner looks okay.
1313 */
1314static int verify_hello(struct ceph_connection *con)
1315{
1316 if (memcmp(con->in_banner, CEPH_BANNER, strlen(CEPH_BANNER))) {
1317 pr_err("connect to %s got bad banner\n",
1318 ceph_pr_addr(&con->peer_addr.in_addr));
1319 con->error_msg = "protocol error, bad banner";
1320 return -1;
1321 }
1322 return 0;
1323}
1324
1325static bool addr_is_blank(struct sockaddr_storage *ss)
1326{
1327 switch (ss->ss_family) {
1328 case AF_INET:
1329 return ((struct sockaddr_in *)ss)->sin_addr.s_addr == 0;
1330 case AF_INET6:
1331 return
1332 ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[0] == 0 &&
1333 ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[1] == 0 &&
1334 ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[2] == 0 &&
1335 ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[3] == 0;
1336 }
1337 return false;
1338}
1339
1340static int addr_port(struct sockaddr_storage *ss)
1341{
1342 switch (ss->ss_family) {
1343 case AF_INET:
1344 return ntohs(((struct sockaddr_in *)ss)->sin_port);
1345 case AF_INET6:
1346 return ntohs(((struct sockaddr_in6 *)ss)->sin6_port);
1347 }
1348 return 0;
1349}
1350
1351static void addr_set_port(struct sockaddr_storage *ss, int p)
1352{
1353 switch (ss->ss_family) {
1354 case AF_INET:
1355 ((struct sockaddr_in *)ss)->sin_port = htons(p);
1356 break;
1357 case AF_INET6:
1358 ((struct sockaddr_in6 *)ss)->sin6_port = htons(p);
1359 break;
1360 }
1361}
1362
1363/*
1364 * Unlike other *_pton function semantics, zero indicates success.
1365 */
1366static int ceph_pton(const char *str, size_t len, struct sockaddr_storage *ss,
1367 char delim, const char **ipend)
1368{
1369 struct sockaddr_in *in4 = (struct sockaddr_in *) ss;
1370 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) ss;
1371
1372 memset(ss, 0, sizeof(*ss));
1373
1374 if (in4_pton(str, len, (u8 *)&in4->sin_addr.s_addr, delim, ipend)) {
1375 ss->ss_family = AF_INET;
1376 return 0;
1377 }
1378
1379 if (in6_pton(str, len, (u8 *)&in6->sin6_addr.s6_addr, delim, ipend)) {
1380 ss->ss_family = AF_INET6;
1381 return 0;
1382 }
1383
1384 return -EINVAL;
1385}
1386
1387/*
1388 * Extract hostname string and resolve using kernel DNS facility.
1389 */
1390#ifdef CONFIG_CEPH_LIB_USE_DNS_RESOLVER
1391static int ceph_dns_resolve_name(const char *name, size_t namelen,
1392 struct sockaddr_storage *ss, char delim, const char **ipend)
1393{
1394 const char *end, *delim_p;
1395 char *colon_p, *ip_addr = NULL;
1396 int ip_len, ret;
1397
1398 /*
1399 * The end of the hostname occurs immediately preceding the delimiter or
1400 * the port marker (':') where the delimiter takes precedence.
1401 */
1402 delim_p = memchr(name, delim, namelen);
1403 colon_p = memchr(name, ':', namelen);
1404
1405 if (delim_p && colon_p)
1406 end = delim_p < colon_p ? delim_p : colon_p;
1407 else if (!delim_p && colon_p)
1408 end = colon_p;
1409 else {
1410 end = delim_p;
1411 if (!end) /* case: hostname:/ */
1412 end = name + namelen;
1413 }
1414
1415 if (end <= name)
1416 return -EINVAL;
1417
1418 /* do dns_resolve upcall */
1419 ip_len = dns_query(NULL, name, end - name, NULL, &ip_addr, NULL);
1420 if (ip_len > 0)
1421 ret = ceph_pton(ip_addr, ip_len, ss, -1, NULL);
1422 else
1423 ret = -ESRCH;
1424
1425 kfree(ip_addr);
1426
1427 *ipend = end;
1428
1429 pr_info("resolve '%.*s' (ret=%d): %s\n", (int)(end - name), name,
1430 ret, ret ? "failed" : ceph_pr_addr(ss));
1431
1432 return ret;
1433}
1434#else
1435static inline int ceph_dns_resolve_name(const char *name, size_t namelen,
1436 struct sockaddr_storage *ss, char delim, const char **ipend)
1437{
1438 return -EINVAL;
1439}
1440#endif
1441
1442/*
1443 * Parse a server name (IP or hostname). If a valid IP address is not found
1444 * then try to extract a hostname to resolve using userspace DNS upcall.
1445 */
1446static int ceph_parse_server_name(const char *name, size_t namelen,
1447 struct sockaddr_storage *ss, char delim, const char **ipend)
1448{
1449 int ret;
1450
1451 ret = ceph_pton(name, namelen, ss, delim, ipend);
1452 if (ret)
1453 ret = ceph_dns_resolve_name(name, namelen, ss, delim, ipend);
1454
1455 return ret;
1456}
1457
1458/*
1459 * Parse an ip[:port] list into an addr array. Use the default
1460 * monitor port if a port isn't specified.
1461 */
1462int ceph_parse_ips(const char *c, const char *end,
1463 struct ceph_entity_addr *addr,
1464 int max_count, int *count)
1465{
1466 int i, ret = -EINVAL;
1467 const char *p = c;
1468
1469 dout("parse_ips on '%.*s'\n", (int)(end-c), c);
1470 for (i = 0; i < max_count; i++) {
1471 const char *ipend;
1472 struct sockaddr_storage *ss = &addr[i].in_addr;
1473 int port;
1474 char delim = ',';
1475
1476 if (*p == '[') {
1477 delim = ']';
1478 p++;
1479 }
1480
1481 ret = ceph_parse_server_name(p, end - p, ss, delim, &ipend);
1482 if (ret)
1483 goto bad;
1484 ret = -EINVAL;
1485
1486 p = ipend;
1487
1488 if (delim == ']') {
1489 if (*p != ']') {
1490 dout("missing matching ']'\n");
1491 goto bad;
1492 }
1493 p++;
1494 }
1495
1496 /* port? */
1497 if (p < end && *p == ':') {
1498 port = 0;
1499 p++;
1500 while (p < end && *p >= '0' && *p <= '9') {
1501 port = (port * 10) + (*p - '0');
1502 p++;
1503 }
1504 if (port > 65535 || port == 0)
1505 goto bad;
1506 } else {
1507 port = CEPH_MON_PORT;
1508 }
1509
1510 addr_set_port(ss, port);
1511
1512 dout("parse_ips got %s\n", ceph_pr_addr(ss));
1513
1514 if (p == end)
1515 break;
1516 if (*p != ',')
1517 goto bad;
1518 p++;
1519 }
1520
1521 if (p != end)
1522 goto bad;
1523
1524 if (count)
1525 *count = i + 1;
1526 return 0;
1527
1528bad:
1529 pr_err("parse_ips bad ip '%.*s'\n", (int)(end - c), c);
1530 return ret;
1531}
1532EXPORT_SYMBOL(ceph_parse_ips);
1533
1534static int process_banner(struct ceph_connection *con)
1535{
1536 dout("process_banner on %p\n", con);
1537
1538 if (verify_hello(con) < 0)
1539 return -1;
1540
1541 ceph_decode_addr(&con->actual_peer_addr);
1542 ceph_decode_addr(&con->peer_addr_for_me);
1543
1544 /*
1545 * Make sure the other end is who we wanted. note that the other
1546 * end may not yet know their ip address, so if it's 0.0.0.0, give
1547 * them the benefit of the doubt.
1548 */
1549 if (memcmp(&con->peer_addr, &con->actual_peer_addr,
1550 sizeof(con->peer_addr)) != 0 &&
1551 !(addr_is_blank(&con->actual_peer_addr.in_addr) &&
1552 con->actual_peer_addr.nonce == con->peer_addr.nonce)) {
1553 pr_warning("wrong peer, want %s/%d, got %s/%d\n",
1554 ceph_pr_addr(&con->peer_addr.in_addr),
1555 (int)le32_to_cpu(con->peer_addr.nonce),
1556 ceph_pr_addr(&con->actual_peer_addr.in_addr),
1557 (int)le32_to_cpu(con->actual_peer_addr.nonce));
1558 con->error_msg = "wrong peer at address";
1559 return -1;
1560 }
1561
1562 /*
1563 * did we learn our address?
1564 */
1565 if (addr_is_blank(&con->msgr->inst.addr.in_addr)) {
1566 int port = addr_port(&con->msgr->inst.addr.in_addr);
1567
1568 memcpy(&con->msgr->inst.addr.in_addr,
1569 &con->peer_addr_for_me.in_addr,
1570 sizeof(con->peer_addr_for_me.in_addr));
1571 addr_set_port(&con->msgr->inst.addr.in_addr, port);
1572 encode_my_addr(con->msgr);
1573 dout("process_banner learned my addr is %s\n",
1574 ceph_pr_addr(&con->msgr->inst.addr.in_addr));
1575 }
1576
1577 return 0;
1578}
1579
1580static int process_connect(struct ceph_connection *con)
1581{
1582 u64 sup_feat = con->msgr->supported_features;
1583 u64 req_feat = con->msgr->required_features;
1584 u64 server_feat = le64_to_cpu(con->in_reply.features);
1585 int ret;
1586
1587 dout("process_connect on %p tag %d\n", con, (int)con->in_tag);
1588
1589 switch (con->in_reply.tag) {
1590 case CEPH_MSGR_TAG_FEATURES:
1591 pr_err("%s%lld %s feature set mismatch,"
1592 " my %llx < server's %llx, missing %llx\n",
1593 ENTITY_NAME(con->peer_name),
1594 ceph_pr_addr(&con->peer_addr.in_addr),
1595 sup_feat, server_feat, server_feat & ~sup_feat);
1596 con->error_msg = "missing required protocol features";
1597 reset_connection(con);
1598 return -1;
1599
1600 case CEPH_MSGR_TAG_BADPROTOVER:
1601 pr_err("%s%lld %s protocol version mismatch,"
1602 " my %d != server's %d\n",
1603 ENTITY_NAME(con->peer_name),
1604 ceph_pr_addr(&con->peer_addr.in_addr),
1605 le32_to_cpu(con->out_connect.protocol_version),
1606 le32_to_cpu(con->in_reply.protocol_version));
1607 con->error_msg = "protocol version mismatch";
1608 reset_connection(con);
1609 return -1;
1610
1611 case CEPH_MSGR_TAG_BADAUTHORIZER:
1612 con->auth_retry++;
1613 dout("process_connect %p got BADAUTHORIZER attempt %d\n", con,
1614 con->auth_retry);
1615 if (con->auth_retry == 2) {
1616 con->error_msg = "connect authorization failure";
1617 return -1;
1618 }
1619 con->auth_retry = 1;
1620 con_out_kvec_reset(con);
1621 ret = prepare_write_connect(con);
1622 if (ret < 0)
1623 return ret;
1624 prepare_read_connect(con);
1625 break;
1626
1627 case CEPH_MSGR_TAG_RESETSESSION:
1628 /*
1629 * If we connected with a large connect_seq but the peer
1630 * has no record of a session with us (no connection, or
1631 * connect_seq == 0), they will send RESETSESION to indicate
1632 * that they must have reset their session, and may have
1633 * dropped messages.
1634 */
1635 dout("process_connect got RESET peer seq %u\n",
1636 le32_to_cpu(con->in_reply.connect_seq));
1637 pr_err("%s%lld %s connection reset\n",
1638 ENTITY_NAME(con->peer_name),
1639 ceph_pr_addr(&con->peer_addr.in_addr));
1640 reset_connection(con);
1641 con_out_kvec_reset(con);
1642 ret = prepare_write_connect(con);
1643 if (ret < 0)
1644 return ret;
1645 prepare_read_connect(con);
1646
1647 /* Tell ceph about it. */
1648 mutex_unlock(&con->mutex);
1649 pr_info("reset on %s%lld\n", ENTITY_NAME(con->peer_name));
1650 if (con->ops->peer_reset)
1651 con->ops->peer_reset(con);
1652 mutex_lock(&con->mutex);
1653 if (con->state != CON_STATE_NEGOTIATING)
1654 return -EAGAIN;
1655 break;
1656
1657 case CEPH_MSGR_TAG_RETRY_SESSION:
1658 /*
1659 * If we sent a smaller connect_seq than the peer has, try
1660 * again with a larger value.
1661 */
1662 dout("process_connect got RETRY_SESSION my seq %u, peer %u\n",
1663 le32_to_cpu(con->out_connect.connect_seq),
1664 le32_to_cpu(con->in_reply.connect_seq));
1665 con->connect_seq = le32_to_cpu(con->in_reply.connect_seq);
1666 con_out_kvec_reset(con);
1667 ret = prepare_write_connect(con);
1668 if (ret < 0)
1669 return ret;
1670 prepare_read_connect(con);
1671 break;
1672
1673 case CEPH_MSGR_TAG_RETRY_GLOBAL:
1674 /*
1675 * If we sent a smaller global_seq than the peer has, try
1676 * again with a larger value.
1677 */
1678 dout("process_connect got RETRY_GLOBAL my %u peer_gseq %u\n",
1679 con->peer_global_seq,
1680 le32_to_cpu(con->in_reply.global_seq));
1681 get_global_seq(con->msgr,
1682 le32_to_cpu(con->in_reply.global_seq));
1683 con_out_kvec_reset(con);
1684 ret = prepare_write_connect(con);
1685 if (ret < 0)
1686 return ret;
1687 prepare_read_connect(con);
1688 break;
1689
1690 case CEPH_MSGR_TAG_READY:
1691 if (req_feat & ~server_feat) {
1692 pr_err("%s%lld %s protocol feature mismatch,"
1693 " my required %llx > server's %llx, need %llx\n",
1694 ENTITY_NAME(con->peer_name),
1695 ceph_pr_addr(&con->peer_addr.in_addr),
1696 req_feat, server_feat, req_feat & ~server_feat);
1697 con->error_msg = "missing required protocol features";
1698 reset_connection(con);
1699 return -1;
1700 }
1701
1702 WARN_ON(con->state != CON_STATE_NEGOTIATING);
1703 con->state = CON_STATE_OPEN;
1704
1705 con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
1706 con->connect_seq++;
1707 con->peer_features = server_feat;
1708 dout("process_connect got READY gseq %d cseq %d (%d)\n",
1709 con->peer_global_seq,
1710 le32_to_cpu(con->in_reply.connect_seq),
1711 con->connect_seq);
1712 WARN_ON(con->connect_seq !=
1713 le32_to_cpu(con->in_reply.connect_seq));
1714
1715 if (con->in_reply.flags & CEPH_MSG_CONNECT_LOSSY)
1716 con_flag_set(con, CON_FLAG_LOSSYTX);
1717
1718 con->delay = 0; /* reset backoff memory */
1719
1720 prepare_read_tag(con);
1721 break;
1722
1723 case CEPH_MSGR_TAG_WAIT:
1724 /*
1725 * If there is a connection race (we are opening
1726 * connections to each other), one of us may just have
1727 * to WAIT. This shouldn't happen if we are the
1728 * client.
1729 */
1730 pr_err("process_connect got WAIT as client\n");
1731 con->error_msg = "protocol error, got WAIT as client";
1732 return -1;
1733
1734 default:
1735 pr_err("connect protocol error, will retry\n");
1736 con->error_msg = "protocol error, garbage tag during connect";
1737 return -1;
1738 }
1739 return 0;
1740}
1741
1742
1743/*
1744 * read (part of) an ack
1745 */
1746static int read_partial_ack(struct ceph_connection *con)
1747{
1748 int size = sizeof (con->in_temp_ack);
1749 int end = size;
1750
1751 return read_partial(con, end, size, &con->in_temp_ack);
1752}
1753
1754
1755/*
1756 * We can finally discard anything that's been acked.
1757 */
1758static void process_ack(struct ceph_connection *con)
1759{
1760 struct ceph_msg *m;
1761 u64 ack = le64_to_cpu(con->in_temp_ack);
1762 u64 seq;
1763
1764 while (!list_empty(&con->out_sent)) {
1765 m = list_first_entry(&con->out_sent, struct ceph_msg,
1766 list_head);
1767 seq = le64_to_cpu(m->hdr.seq);
1768 if (seq > ack)
1769 break;
1770 dout("got ack for seq %llu type %d at %p\n", seq,
1771 le16_to_cpu(m->hdr.type), m);
1772 m->ack_stamp = jiffies;
1773 ceph_msg_remove(m);
1774 }
1775 prepare_read_tag(con);
1776}
1777
1778
1779
1780
1781static int read_partial_message_section(struct ceph_connection *con,
1782 struct kvec *section,
1783 unsigned int sec_len, u32 *crc)
1784{
1785 int ret, left;
1786
1787 BUG_ON(!section);
1788
1789 while (section->iov_len < sec_len) {
1790 BUG_ON(section->iov_base == NULL);
1791 left = sec_len - section->iov_len;
1792 ret = ceph_tcp_recvmsg(con->sock, (char *)section->iov_base +
1793 section->iov_len, left);
1794 if (ret <= 0)
1795 return ret;
1796 section->iov_len += ret;
1797 }
1798 if (section->iov_len == sec_len)
1799 *crc = crc32c(0, section->iov_base, section->iov_len);
1800
1801 return 1;
1802}
1803
1804static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip);
1805
1806static int read_partial_message_pages(struct ceph_connection *con,
1807 struct page **pages,
1808 unsigned int data_len, bool do_datacrc)
1809{
1810 struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
1811 struct page *page;
1812 void *p;
1813 int ret;
1814 int left;
1815
1816 left = min((int)(data_len - msg_pos->data_pos),
1817 (int)(PAGE_SIZE - msg_pos->page_pos));
1818 /* (page) data */
1819 BUG_ON(pages == NULL);
1820 page = pages[msg_pos->page];
1821 p = kmap(page);
1822 ret = ceph_tcp_recvmsg(con->sock, p + msg_pos->page_pos, left);
1823 if (ret > 0 && do_datacrc)
1824 con->in_data_crc =
1825 crc32c(con->in_data_crc,
1826 p + msg_pos->page_pos, ret);
1827 kunmap(page);
1828 if (ret <= 0)
1829 return ret;
1830
1831 in_msg_pos_next(con, left, ret);
1832
1833 return ret;
1834}
1835
1836#ifdef CONFIG_BLOCK
1837static int read_partial_message_bio(struct ceph_connection *con,
1838 unsigned int data_len, bool do_datacrc)
1839{
1840 struct ceph_msg *msg = con->in_msg;
1841 struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
1842 struct bio_vec *bv;
1843 struct page *page;
1844 void *p;
1845 int ret, left;
1846
1847 BUG_ON(!msg);
1848 BUG_ON(!msg->bio_iter);
1849 bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
1850
1851 left = min((int)(data_len - msg_pos->data_pos),
1852 (int)(bv->bv_len - msg_pos->page_pos));
1853
1854 page = bv->bv_page;
1855 p = kmap(page) + bv->bv_offset;
1856
1857 ret = ceph_tcp_recvmsg(con->sock, p + msg_pos->page_pos, left);
1858 if (ret > 0 && do_datacrc)
1859 con->in_data_crc =
1860 crc32c(con->in_data_crc,
1861 p + msg_pos->page_pos, ret);
1862 kunmap(page);
1863 if (ret <= 0)
1864 return ret;
1865
1866 in_msg_pos_next(con, left, ret);
1867
1868 return ret;
1869}
1870#endif
1871
1872/*
1873 * read (part of) a message.
1874 */
1875static int read_partial_message(struct ceph_connection *con)
1876{
1877 struct ceph_msg *m = con->in_msg;
1878 struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
1879 int size;
1880 int end;
1881 int ret;
1882 unsigned int front_len, middle_len, data_len;
1883 bool do_datacrc = !con->msgr->nocrc;
1884 u64 seq;
1885 u32 crc;
1886
1887 dout("read_partial_message con %p msg %p\n", con, m);
1888
1889 /* header */
1890 size = sizeof (con->in_hdr);
1891 end = size;
1892 ret = read_partial(con, end, size, &con->in_hdr);
1893 if (ret <= 0)
1894 return ret;
1895
1896 crc = crc32c(0, &con->in_hdr, offsetof(struct ceph_msg_header, crc));
1897 if (cpu_to_le32(crc) != con->in_hdr.crc) {
1898 pr_err("read_partial_message bad hdr "
1899 " crc %u != expected %u\n",
1900 crc, con->in_hdr.crc);
1901 return -EBADMSG;
1902 }
1903
1904 front_len = le32_to_cpu(con->in_hdr.front_len);
1905 if (front_len > CEPH_MSG_MAX_FRONT_LEN)
1906 return -EIO;
1907 middle_len = le32_to_cpu(con->in_hdr.middle_len);
1908 if (middle_len > CEPH_MSG_MAX_MIDDLE_LEN)
1909 return -EIO;
1910 data_len = le32_to_cpu(con->in_hdr.data_len);
1911 if (data_len > CEPH_MSG_MAX_DATA_LEN)
1912 return -EIO;
1913
1914 /* verify seq# */
1915 seq = le64_to_cpu(con->in_hdr.seq);
1916 if ((s64)seq - (s64)con->in_seq < 1) {
1917 pr_info("skipping %s%lld %s seq %lld expected %lld\n",
1918 ENTITY_NAME(con->peer_name),
1919 ceph_pr_addr(&con->peer_addr.in_addr),
1920 seq, con->in_seq + 1);
1921 con->in_base_pos = -front_len - middle_len - data_len -
1922 sizeof(m->footer);
1923 con->in_tag = CEPH_MSGR_TAG_READY;
1924 return 0;
1925 } else if ((s64)seq - (s64)con->in_seq > 1) {
1926 pr_err("read_partial_message bad seq %lld expected %lld\n",
1927 seq, con->in_seq + 1);
1928 con->error_msg = "bad message sequence # for incoming message";
1929 return -EBADMSG;
1930 }
1931
1932 /* allocate message? */
1933 if (!con->in_msg) {
1934 int skip = 0;
1935
1936 dout("got hdr type %d front %d data %d\n", con->in_hdr.type,
1937 front_len, data_len);
1938 ret = ceph_con_in_msg_alloc(con, &skip);
1939 if (ret < 0)
1940 return ret;
1941 if (skip) {
1942 /* skip this message */
1943 dout("alloc_msg said skip message\n");
1944 BUG_ON(con->in_msg);
1945 con->in_base_pos = -front_len - middle_len - data_len -
1946 sizeof(m->footer);
1947 con->in_tag = CEPH_MSGR_TAG_READY;
1948 con->in_seq++;
1949 return 0;
1950 }
1951
1952 BUG_ON(!con->in_msg);
1953 BUG_ON(con->in_msg->con != con);
1954 m = con->in_msg;
1955 m->front.iov_len = 0; /* haven't read it yet */
1956 if (m->middle)
1957 m->middle->vec.iov_len = 0;
1958
1959 msg_pos->page = 0;
1960 if (m->pages)
1961 msg_pos->page_pos = m->page_alignment;
1962 else
1963 msg_pos->page_pos = 0;
1964 msg_pos->data_pos = 0;
1965
1966#ifdef CONFIG_BLOCK
1967 if (m->bio)
1968 init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg);
1969#endif
1970 }
1971
1972 /* front */
1973 ret = read_partial_message_section(con, &m->front, front_len,
1974 &con->in_front_crc);
1975 if (ret <= 0)
1976 return ret;
1977
1978 /* middle */
1979 if (m->middle) {
1980 ret = read_partial_message_section(con, &m->middle->vec,
1981 middle_len,
1982 &con->in_middle_crc);
1983 if (ret <= 0)
1984 return ret;
1985 }
1986
1987 /* (page) data */
1988 while (msg_pos->data_pos < data_len) {
1989 if (m->pages) {
1990 ret = read_partial_message_pages(con, m->pages,
1991 data_len, do_datacrc);
1992 if (ret <= 0)
1993 return ret;
1994#ifdef CONFIG_BLOCK
1995 } else if (m->bio) {
1996 ret = read_partial_message_bio(con,
1997 data_len, do_datacrc);
1998 if (ret <= 0)
1999 return ret;
2000#endif
2001 } else {
2002 BUG_ON(1);
2003 }
2004 }
2005
2006 /* footer */
2007 size = sizeof (m->footer);
2008 end += size;
2009 ret = read_partial(con, end, size, &m->footer);
2010 if (ret <= 0)
2011 return ret;
2012
2013 dout("read_partial_message got msg %p %d (%u) + %d (%u) + %d (%u)\n",
2014 m, front_len, m->footer.front_crc, middle_len,
2015 m->footer.middle_crc, data_len, m->footer.data_crc);
2016
2017 /* crc ok? */
2018 if (con->in_front_crc != le32_to_cpu(m->footer.front_crc)) {
2019 pr_err("read_partial_message %p front crc %u != exp. %u\n",
2020 m, con->in_front_crc, m->footer.front_crc);
2021 return -EBADMSG;
2022 }
2023 if (con->in_middle_crc != le32_to_cpu(m->footer.middle_crc)) {
2024 pr_err("read_partial_message %p middle crc %u != exp %u\n",
2025 m, con->in_middle_crc, m->footer.middle_crc);
2026 return -EBADMSG;
2027 }
2028 if (do_datacrc &&
2029 (m->footer.flags & CEPH_MSG_FOOTER_NOCRC) == 0 &&
2030 con->in_data_crc != le32_to_cpu(m->footer.data_crc)) {
2031 pr_err("read_partial_message %p data crc %u != exp. %u\n", m,
2032 con->in_data_crc, le32_to_cpu(m->footer.data_crc));
2033 return -EBADMSG;
2034 }
2035
2036 return 1; /* done! */
2037}
2038
2039/*
2040 * Process message. This happens in the worker thread. The callback should
2041 * be careful not to do anything that waits on other incoming messages or it
2042 * may deadlock.
2043 */
2044static void process_message(struct ceph_connection *con)
2045{
2046 struct ceph_msg *msg;
2047
2048 BUG_ON(con->in_msg->con != con);
2049 con->in_msg->con = NULL;
2050 msg = con->in_msg;
2051 con->in_msg = NULL;
2052 con->ops->put(con);
2053
2054 /* if first message, set peer_name */
2055 if (con->peer_name.type == 0)
2056 con->peer_name = msg->hdr.src;
2057
2058 con->in_seq++;
2059 mutex_unlock(&con->mutex);
2060
2061 dout("===== %p %llu from %s%lld %d=%s len %d+%d (%u %u %u) =====\n",
2062 msg, le64_to_cpu(msg->hdr.seq),
2063 ENTITY_NAME(msg->hdr.src),
2064 le16_to_cpu(msg->hdr.type),
2065 ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
2066 le32_to_cpu(msg->hdr.front_len),
2067 le32_to_cpu(msg->hdr.data_len),
2068 con->in_front_crc, con->in_middle_crc, con->in_data_crc);
2069 con->ops->dispatch(con, msg);
2070
2071 mutex_lock(&con->mutex);
2072}
2073
2074
2075/*
2076 * Write something to the socket. Called in a worker thread when the
2077 * socket appears to be writeable and we have something ready to send.
2078 */
2079static int try_write(struct ceph_connection *con)
2080{
2081 int ret = 1;
2082
2083 dout("try_write start %p state %lu\n", con, con->state);
2084
2085more:
2086 dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes);
2087
2088 /* open the socket first? */
2089 if (con->state == CON_STATE_PREOPEN) {
2090 BUG_ON(con->sock);
2091 con->state = CON_STATE_CONNECTING;
2092
2093 con_out_kvec_reset(con);
2094 prepare_write_banner(con);
2095 prepare_read_banner(con);
2096
2097 BUG_ON(con->in_msg);
2098 con->in_tag = CEPH_MSGR_TAG_READY;
2099 dout("try_write initiating connect on %p new state %lu\n",
2100 con, con->state);
2101 ret = ceph_tcp_connect(con);
2102 if (ret < 0) {
2103 con->error_msg = "connect error";
2104 goto out;
2105 }
2106 }
2107
2108more_kvec:
2109 /* kvec data queued? */
2110 if (con->out_skip) {
2111 ret = write_partial_skip(con);
2112 if (ret <= 0)
2113 goto out;
2114 }
2115 if (con->out_kvec_left) {
2116 ret = write_partial_kvec(con);
2117 if (ret <= 0)
2118 goto out;
2119 }
2120
2121 /* msg pages? */
2122 if (con->out_msg) {
2123 if (con->out_msg_done) {
2124 ceph_msg_put(con->out_msg);
2125 con->out_msg = NULL; /* we're done with this one */
2126 goto do_next;
2127 }
2128
2129 ret = write_partial_msg_pages(con);
2130 if (ret == 1)
2131 goto more_kvec; /* we need to send the footer, too! */
2132 if (ret == 0)
2133 goto out;
2134 if (ret < 0) {
2135 dout("try_write write_partial_msg_pages err %d\n",
2136 ret);
2137 goto out;
2138 }
2139 }
2140
2141do_next:
2142 if (con->state == CON_STATE_OPEN) {
2143 /* is anything else pending? */
2144 if (!list_empty(&con->out_queue)) {
2145 prepare_write_message(con);
2146 goto more;
2147 }
2148 if (con->in_seq > con->in_seq_acked) {
2149 prepare_write_ack(con);
2150 goto more;
2151 }
2152 if (con_flag_test_and_clear(con, CON_FLAG_KEEPALIVE_PENDING)) {
2153 prepare_write_keepalive(con);
2154 goto more;
2155 }
2156 }
2157
2158 /* Nothing to do! */
2159 con_flag_clear(con, CON_FLAG_WRITE_PENDING);
2160 dout("try_write nothing else to write.\n");
2161 ret = 0;
2162out:
2163 dout("try_write done on %p ret %d\n", con, ret);
2164 return ret;
2165}
2166
2167
2168
2169/*
2170 * Read what we can from the socket.
2171 */
2172static int try_read(struct ceph_connection *con)
2173{
2174 int ret = -1;
2175
2176more:
2177 dout("try_read start on %p state %lu\n", con, con->state);
2178 if (con->state != CON_STATE_CONNECTING &&
2179 con->state != CON_STATE_NEGOTIATING &&
2180 con->state != CON_STATE_OPEN)
2181 return 0;
2182
2183 BUG_ON(!con->sock);
2184
2185 dout("try_read tag %d in_base_pos %d\n", (int)con->in_tag,
2186 con->in_base_pos);
2187
2188 if (con->state == CON_STATE_CONNECTING) {
2189 dout("try_read connecting\n");
2190 ret = read_partial_banner(con);
2191 if (ret <= 0)
2192 goto out;
2193 ret = process_banner(con);
2194 if (ret < 0)
2195 goto out;
2196
2197 con->state = CON_STATE_NEGOTIATING;
2198
2199 /*
2200 * Received banner is good, exchange connection info.
2201 * Do not reset out_kvec, as sending our banner raced
2202 * with receiving peer banner after connect completed.
2203 */
2204 ret = prepare_write_connect(con);
2205 if (ret < 0)
2206 goto out;
2207 prepare_read_connect(con);
2208
2209 /* Send connection info before awaiting response */
2210 goto out;
2211 }
2212
2213 if (con->state == CON_STATE_NEGOTIATING) {
2214 dout("try_read negotiating\n");
2215 ret = read_partial_connect(con);
2216 if (ret <= 0)
2217 goto out;
2218 ret = process_connect(con);
2219 if (ret < 0)
2220 goto out;
2221 goto more;
2222 }
2223
2224 WARN_ON(con->state != CON_STATE_OPEN);
2225
2226 if (con->in_base_pos < 0) {
2227 /*
2228 * skipping + discarding content.
2229 *
2230 * FIXME: there must be a better way to do this!
2231 */
2232 static char buf[SKIP_BUF_SIZE];
2233 int skip = min((int) sizeof (buf), -con->in_base_pos);
2234
2235 dout("skipping %d / %d bytes\n", skip, -con->in_base_pos);
2236 ret = ceph_tcp_recvmsg(con->sock, buf, skip);
2237 if (ret <= 0)
2238 goto out;
2239 con->in_base_pos += ret;
2240 if (con->in_base_pos)
2241 goto more;
2242 }
2243 if (con->in_tag == CEPH_MSGR_TAG_READY) {
2244 /*
2245 * what's next?
2246 */
2247 ret = ceph_tcp_recvmsg(con->sock, &con->in_tag, 1);
2248 if (ret <= 0)
2249 goto out;
2250 dout("try_read got tag %d\n", (int)con->in_tag);
2251 switch (con->in_tag) {
2252 case CEPH_MSGR_TAG_MSG:
2253 prepare_read_message(con);
2254 break;
2255 case CEPH_MSGR_TAG_ACK:
2256 prepare_read_ack(con);
2257 break;
2258 case CEPH_MSGR_TAG_CLOSE:
2259 con_close_socket(con);
2260 con->state = CON_STATE_CLOSED;
2261 goto out;
2262 default:
2263 goto bad_tag;
2264 }
2265 }
2266 if (con->in_tag == CEPH_MSGR_TAG_MSG) {
2267 ret = read_partial_message(con);
2268 if (ret <= 0) {
2269 switch (ret) {
2270 case -EBADMSG:
2271 con->error_msg = "bad crc";
2272 ret = -EIO;
2273 break;
2274 case -EIO:
2275 con->error_msg = "io error";
2276 break;
2277 }
2278 goto out;
2279 }
2280 if (con->in_tag == CEPH_MSGR_TAG_READY)
2281 goto more;
2282 process_message(con);
2283 if (con->state == CON_STATE_OPEN)
2284 prepare_read_tag(con);
2285 goto more;
2286 }
2287 if (con->in_tag == CEPH_MSGR_TAG_ACK) {
2288 ret = read_partial_ack(con);
2289 if (ret <= 0)
2290 goto out;
2291 process_ack(con);
2292 goto more;
2293 }
2294
2295out:
2296 dout("try_read done on %p ret %d\n", con, ret);
2297 return ret;
2298
2299bad_tag:
2300 pr_err("try_read bad con->in_tag = %d\n", (int)con->in_tag);
2301 con->error_msg = "protocol error, garbage tag";
2302 ret = -1;
2303 goto out;
2304}
2305
2306
2307/*
2308 * Atomically queue work on a connection after the specified delay.
2309 * Bump @con reference to avoid races with connection teardown.
2310 * Returns 0 if work was queued, or an error code otherwise.
2311 */
2312static int queue_con_delay(struct ceph_connection *con, unsigned long delay)
2313{
2314 if (!con->ops->get(con)) {
2315 dout("%s %p ref count 0\n", __func__, con);
2316
2317 return -ENOENT;
2318 }
2319
2320 if (!queue_delayed_work(ceph_msgr_wq, &con->work, delay)) {
2321 dout("%s %p - already queued\n", __func__, con);
2322 con->ops->put(con);
2323
2324 return -EBUSY;
2325 }
2326
2327 dout("%s %p %lu\n", __func__, con, delay);
2328
2329 return 0;
2330}
2331
2332static void queue_con(struct ceph_connection *con)
2333{
2334 (void) queue_con_delay(con, 0);
2335}
2336
2337static bool con_sock_closed(struct ceph_connection *con)
2338{
2339 if (!con_flag_test_and_clear(con, CON_FLAG_SOCK_CLOSED))
2340 return false;
2341
2342#define CASE(x) \
2343 case CON_STATE_ ## x: \
2344 con->error_msg = "socket closed (con state " #x ")"; \
2345 break;
2346
2347 switch (con->state) {
2348 CASE(CLOSED);
2349 CASE(PREOPEN);
2350 CASE(CONNECTING);
2351 CASE(NEGOTIATING);
2352 CASE(OPEN);
2353 CASE(STANDBY);
2354 default:
2355 pr_warning("%s con %p unrecognized state %lu\n",
2356 __func__, con, con->state);
2357 con->error_msg = "unrecognized con state";
2358 BUG();
2359 break;
2360 }
2361#undef CASE
2362
2363 return true;
2364}
2365
2366static bool con_backoff(struct ceph_connection *con)
2367{
2368 int ret;
2369
2370 if (!con_flag_test_and_clear(con, CON_FLAG_BACKOFF))
2371 return false;
2372
2373 ret = queue_con_delay(con, round_jiffies_relative(con->delay));
2374 if (ret) {
2375 dout("%s: con %p FAILED to back off %lu\n", __func__,
2376 con, con->delay);
2377 BUG_ON(ret == -ENOENT);
2378 con_flag_set(con, CON_FLAG_BACKOFF);
2379 }
2380
2381 return true;
2382}
2383
2384/* Finish fault handling; con->mutex must *not* be held here */
2385
2386static void con_fault_finish(struct ceph_connection *con)
2387{
2388 /*
2389 * in case we faulted due to authentication, invalidate our
2390 * current tickets so that we can get new ones.
2391 */
2392 if (con->auth_retry && con->ops->invalidate_authorizer) {
2393 dout("calling invalidate_authorizer()\n");
2394 con->ops->invalidate_authorizer(con);
2395 }
2396
2397 if (con->ops->fault)
2398 con->ops->fault(con);
2399}
2400
2401/*
2402 * Do some work on a connection. Drop a connection ref when we're done.
2403 */
2404static void con_work(struct work_struct *work)
2405{
2406 struct ceph_connection *con = container_of(work, struct ceph_connection,
2407 work.work);
2408 bool fault;
2409
2410 mutex_lock(&con->mutex);
2411 while (true) {
2412 int ret;
2413
2414 if ((fault = con_sock_closed(con))) {
2415 dout("%s: con %p SOCK_CLOSED\n", __func__, con);
2416 break;
2417 }
2418 if (con_backoff(con)) {
2419 dout("%s: con %p BACKOFF\n", __func__, con);
2420 break;
2421 }
2422 if (con->state == CON_STATE_STANDBY) {
2423 dout("%s: con %p STANDBY\n", __func__, con);
2424 break;
2425 }
2426 if (con->state == CON_STATE_CLOSED) {
2427 dout("%s: con %p CLOSED\n", __func__, con);
2428 BUG_ON(con->sock);
2429 break;
2430 }
2431 if (con->state == CON_STATE_PREOPEN) {
2432 dout("%s: con %p PREOPEN\n", __func__, con);
2433 BUG_ON(con->sock);
2434 }
2435
2436 ret = try_read(con);
2437 if (ret < 0) {
2438 if (ret == -EAGAIN)
2439 continue;
2440 con->error_msg = "socket error on read";
2441 fault = true;
2442 break;
2443 }
2444
2445 ret = try_write(con);
2446 if (ret < 0) {
2447 if (ret == -EAGAIN)
2448 continue;
2449 con->error_msg = "socket error on write";
2450 fault = true;
2451 }
2452
2453 break; /* If we make it to here, we're done */
2454 }
2455 if (fault)
2456 con_fault(con);
2457 mutex_unlock(&con->mutex);
2458
2459 if (fault)
2460 con_fault_finish(con);
2461
2462 con->ops->put(con);
2463}
2464
2465/*
2466 * Generic error/fault handler. A retry mechanism is used with
2467 * exponential backoff
2468 */
2469static void con_fault(struct ceph_connection *con)
2470{
2471 pr_warning("%s%lld %s %s\n", ENTITY_NAME(con->peer_name),
2472 ceph_pr_addr(&con->peer_addr.in_addr), con->error_msg);
2473 dout("fault %p state %lu to peer %s\n",
2474 con, con->state, ceph_pr_addr(&con->peer_addr.in_addr));
2475
2476 WARN_ON(con->state != CON_STATE_CONNECTING &&
2477 con->state != CON_STATE_NEGOTIATING &&
2478 con->state != CON_STATE_OPEN);
2479
2480 con_close_socket(con);
2481
2482 if (con_flag_test(con, CON_FLAG_LOSSYTX)) {
2483 dout("fault on LOSSYTX channel, marking CLOSED\n");
2484 con->state = CON_STATE_CLOSED;
2485 return;
2486 }
2487
2488 if (con->in_msg) {
2489 BUG_ON(con->in_msg->con != con);
2490 con->in_msg->con = NULL;
2491 ceph_msg_put(con->in_msg);
2492 con->in_msg = NULL;
2493 con->ops->put(con);
2494 }
2495
2496 /* Requeue anything that hasn't been acked */
2497 list_splice_init(&con->out_sent, &con->out_queue);
2498
2499 /* If there are no messages queued or keepalive pending, place
2500 * the connection in a STANDBY state */
2501 if (list_empty(&con->out_queue) &&
2502 !con_flag_test(con, CON_FLAG_KEEPALIVE_PENDING)) {
2503 dout("fault %p setting STANDBY clearing WRITE_PENDING\n", con);
2504 con_flag_clear(con, CON_FLAG_WRITE_PENDING);
2505 con->state = CON_STATE_STANDBY;
2506 } else {
2507 /* retry after a delay. */
2508 con->state = CON_STATE_PREOPEN;
2509 if (con->delay == 0)
2510 con->delay = BASE_DELAY_INTERVAL;
2511 else if (con->delay < MAX_DELAY_INTERVAL)
2512 con->delay *= 2;
2513 con_flag_set(con, CON_FLAG_BACKOFF);
2514 queue_con(con);
2515 }
2516}
2517
2518
2519
2520/*
2521 * initialize a new messenger instance
2522 */
2523void ceph_messenger_init(struct ceph_messenger *msgr,
2524 struct ceph_entity_addr *myaddr,
2525 u32 supported_features,
2526 u32 required_features,
2527 bool nocrc)
2528{
2529 msgr->supported_features = supported_features;
2530 msgr->required_features = required_features;
2531
2532 spin_lock_init(&msgr->global_seq_lock);
2533
2534 if (myaddr)
2535 msgr->inst.addr = *myaddr;
2536
2537 /* select a random nonce */
2538 msgr->inst.addr.type = 0;
2539 get_random_bytes(&msgr->inst.addr.nonce, sizeof(msgr->inst.addr.nonce));
2540 encode_my_addr(msgr);
2541 msgr->nocrc = nocrc;
2542
2543 atomic_set(&msgr->stopping, 0);
2544
2545 dout("%s %p\n", __func__, msgr);
2546}
2547EXPORT_SYMBOL(ceph_messenger_init);
2548
2549static void clear_standby(struct ceph_connection *con)
2550{
2551 /* come back from STANDBY? */
2552 if (con->state == CON_STATE_STANDBY) {
2553 dout("clear_standby %p and ++connect_seq\n", con);
2554 con->state = CON_STATE_PREOPEN;
2555 con->connect_seq++;
2556 WARN_ON(con_flag_test(con, CON_FLAG_WRITE_PENDING));
2557 WARN_ON(con_flag_test(con, CON_FLAG_KEEPALIVE_PENDING));
2558 }
2559}
2560
2561/*
2562 * Queue up an outgoing message on the given connection.
2563 */
2564void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg)
2565{
2566 /* set src+dst */
2567 msg->hdr.src = con->msgr->inst.name;
2568 BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len));
2569 msg->needs_out_seq = true;
2570
2571 mutex_lock(&con->mutex);
2572
2573 if (con->state == CON_STATE_CLOSED) {
2574 dout("con_send %p closed, dropping %p\n", con, msg);
2575 ceph_msg_put(msg);
2576 mutex_unlock(&con->mutex);
2577 return;
2578 }
2579
2580 BUG_ON(msg->con != NULL);
2581 msg->con = con->ops->get(con);
2582 BUG_ON(msg->con == NULL);
2583
2584 BUG_ON(!list_empty(&msg->list_head));
2585 list_add_tail(&msg->list_head, &con->out_queue);
2586 dout("----- %p to %s%lld %d=%s len %d+%d+%d -----\n", msg,
2587 ENTITY_NAME(con->peer_name), le16_to_cpu(msg->hdr.type),
2588 ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
2589 le32_to_cpu(msg->hdr.front_len),
2590 le32_to_cpu(msg->hdr.middle_len),
2591 le32_to_cpu(msg->hdr.data_len));
2592
2593 clear_standby(con);
2594 mutex_unlock(&con->mutex);
2595
2596 /* if there wasn't anything waiting to send before, queue
2597 * new work */
2598 if (con_flag_test_and_set(con, CON_FLAG_WRITE_PENDING) == 0)
2599 queue_con(con);
2600}
2601EXPORT_SYMBOL(ceph_con_send);
2602
2603/*
2604 * Revoke a message that was previously queued for send
2605 */
2606void ceph_msg_revoke(struct ceph_msg *msg)
2607{
2608 struct ceph_connection *con = msg->con;
2609
2610 if (!con)
2611 return; /* Message not in our possession */
2612
2613 mutex_lock(&con->mutex);
2614 if (!list_empty(&msg->list_head)) {
2615 dout("%s %p msg %p - was on queue\n", __func__, con, msg);
2616 list_del_init(&msg->list_head);
2617 BUG_ON(msg->con == NULL);
2618 msg->con->ops->put(msg->con);
2619 msg->con = NULL;
2620 msg->hdr.seq = 0;
2621
2622 ceph_msg_put(msg);
2623 }
2624 if (con->out_msg == msg) {
2625 dout("%s %p msg %p - was sending\n", __func__, con, msg);
2626 con->out_msg = NULL;
2627 if (con->out_kvec_is_msg) {
2628 con->out_skip = con->out_kvec_bytes;
2629 con->out_kvec_is_msg = false;
2630 }
2631 msg->hdr.seq = 0;
2632
2633 ceph_msg_put(msg);
2634 }
2635 mutex_unlock(&con->mutex);
2636}
2637
2638/*
2639 * Revoke a message that we may be reading data into
2640 */
2641void ceph_msg_revoke_incoming(struct ceph_msg *msg)
2642{
2643 struct ceph_connection *con;
2644
2645 BUG_ON(msg == NULL);
2646 if (!msg->con) {
2647 dout("%s msg %p null con\n", __func__, msg);
2648
2649 return; /* Message not in our possession */
2650 }
2651
2652 con = msg->con;
2653 mutex_lock(&con->mutex);
2654 if (con->in_msg == msg) {
2655 unsigned int front_len = le32_to_cpu(con->in_hdr.front_len);
2656 unsigned int middle_len = le32_to_cpu(con->in_hdr.middle_len);
2657 unsigned int data_len = le32_to_cpu(con->in_hdr.data_len);
2658
2659 /* skip rest of message */
2660 dout("%s %p msg %p revoked\n", __func__, con, msg);
2661 con->in_base_pos = con->in_base_pos -
2662 sizeof(struct ceph_msg_header) -
2663 front_len -
2664 middle_len -
2665 data_len -
2666 sizeof(struct ceph_msg_footer);
2667 ceph_msg_put(con->in_msg);
2668 con->in_msg = NULL;
2669 con->in_tag = CEPH_MSGR_TAG_READY;
2670 con->in_seq++;
2671 } else {
2672 dout("%s %p in_msg %p msg %p no-op\n",
2673 __func__, con, con->in_msg, msg);
2674 }
2675 mutex_unlock(&con->mutex);
2676}
2677
2678/*
2679 * Queue a keepalive byte to ensure the tcp connection is alive.
2680 */
2681void ceph_con_keepalive(struct ceph_connection *con)
2682{
2683 dout("con_keepalive %p\n", con);
2684 mutex_lock(&con->mutex);
2685 clear_standby(con);
2686 mutex_unlock(&con->mutex);
2687 if (con_flag_test_and_set(con, CON_FLAG_KEEPALIVE_PENDING) == 0 &&
2688 con_flag_test_and_set(con, CON_FLAG_WRITE_PENDING) == 0)
2689 queue_con(con);
2690}
2691EXPORT_SYMBOL(ceph_con_keepalive);
2692
2693void ceph_msg_data_set_pages(struct ceph_msg *msg, struct page **pages,
2694 size_t length, size_t alignment)
2695{
2696 BUG_ON(!pages);
2697 BUG_ON(!length);
2698 BUG_ON(msg->pages);
2699 BUG_ON(msg->length);
2700
2701 msg->pages = pages;
2702 msg->length = length;
2703 msg->page_alignment = alignment & ~PAGE_MASK;
2704}
2705EXPORT_SYMBOL(ceph_msg_data_set_pages);
2706
2707void ceph_msg_data_set_pagelist(struct ceph_msg *msg,
2708 struct ceph_pagelist *pagelist)
2709{
2710 BUG_ON(!pagelist);
2711 BUG_ON(!pagelist->length);
2712 BUG_ON(msg->pagelist);
2713
2714 msg->pagelist = pagelist;
2715}
2716EXPORT_SYMBOL(ceph_msg_data_set_pagelist);
2717
2718void ceph_msg_data_set_bio(struct ceph_msg *msg, struct bio *bio)
2719{
2720 BUG_ON(!bio);
2721 BUG_ON(msg->bio);
2722
2723 msg->bio = bio;
2724}
2725EXPORT_SYMBOL(ceph_msg_data_set_bio);
2726
2727void ceph_msg_data_set_trail(struct ceph_msg *msg, struct ceph_pagelist *trail)
2728{
2729 BUG_ON(!trail);
2730 BUG_ON(!trail->length);
2731 BUG_ON(msg->trail);
2732
2733 msg->trail = trail;
2734}
2735EXPORT_SYMBOL(ceph_msg_data_set_trail);
2736
2737/*
2738 * construct a new message with given type, size
2739 * the new msg has a ref count of 1.
2740 */
2741struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
2742 bool can_fail)
2743{
2744 struct ceph_msg *m;
2745
2746 m = kzalloc(sizeof(*m), flags);
2747 if (m == NULL)
2748 goto out;
2749
2750 m->hdr.type = cpu_to_le16(type);
2751 m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT);
2752 m->hdr.front_len = cpu_to_le32(front_len);
2753
2754 INIT_LIST_HEAD(&m->list_head);
2755 kref_init(&m->kref);
2756
2757 /* front */
2758 m->front_max = front_len;
2759 if (front_len) {
2760 if (front_len > PAGE_CACHE_SIZE) {
2761 m->front.iov_base = __vmalloc(front_len, flags,
2762 PAGE_KERNEL);
2763 m->front_is_vmalloc = true;
2764 } else {
2765 m->front.iov_base = kmalloc(front_len, flags);
2766 }
2767 if (m->front.iov_base == NULL) {
2768 dout("ceph_msg_new can't allocate %d bytes\n",
2769 front_len);
2770 goto out2;
2771 }
2772 } else {
2773 m->front.iov_base = NULL;
2774 }
2775 m->front.iov_len = front_len;
2776
2777 dout("ceph_msg_new %p front %d\n", m, front_len);
2778 return m;
2779
2780out2:
2781 ceph_msg_put(m);
2782out:
2783 if (!can_fail) {
2784 pr_err("msg_new can't create type %d front %d\n", type,
2785 front_len);
2786 WARN_ON(1);
2787 } else {
2788 dout("msg_new can't create type %d front %d\n", type,
2789 front_len);
2790 }
2791 return NULL;
2792}
2793EXPORT_SYMBOL(ceph_msg_new);
2794
2795/*
2796 * Allocate "middle" portion of a message, if it is needed and wasn't
2797 * allocated by alloc_msg. This allows us to read a small fixed-size
2798 * per-type header in the front and then gracefully fail (i.e.,
2799 * propagate the error to the caller based on info in the front) when
2800 * the middle is too large.
2801 */
2802static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg)
2803{
2804 int type = le16_to_cpu(msg->hdr.type);
2805 int middle_len = le32_to_cpu(msg->hdr.middle_len);
2806
2807 dout("alloc_middle %p type %d %s middle_len %d\n", msg, type,
2808 ceph_msg_type_name(type), middle_len);
2809 BUG_ON(!middle_len);
2810 BUG_ON(msg->middle);
2811
2812 msg->middle = ceph_buffer_new(middle_len, GFP_NOFS);
2813 if (!msg->middle)
2814 return -ENOMEM;
2815 return 0;
2816}
2817
2818/*
2819 * Allocate a message for receiving an incoming message on a
2820 * connection, and save the result in con->in_msg. Uses the
2821 * connection's private alloc_msg op if available.
2822 *
2823 * Returns 0 on success, or a negative error code.
2824 *
2825 * On success, if we set *skip = 1:
2826 * - the next message should be skipped and ignored.
2827 * - con->in_msg == NULL
2828 * or if we set *skip = 0:
2829 * - con->in_msg is non-null.
2830 * On error (ENOMEM, EAGAIN, ...),
2831 * - con->in_msg == NULL
2832 */
2833static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip)
2834{
2835 struct ceph_msg_header *hdr = &con->in_hdr;
2836 int middle_len = le32_to_cpu(hdr->middle_len);
2837 struct ceph_msg *msg;
2838 int ret = 0;
2839
2840 BUG_ON(con->in_msg != NULL);
2841 BUG_ON(!con->ops->alloc_msg);
2842
2843 mutex_unlock(&con->mutex);
2844 msg = con->ops->alloc_msg(con, hdr, skip);
2845 mutex_lock(&con->mutex);
2846 if (con->state != CON_STATE_OPEN) {
2847 if (msg)
2848 ceph_msg_put(msg);
2849 return -EAGAIN;
2850 }
2851 if (msg) {
2852 BUG_ON(*skip);
2853 con->in_msg = msg;
2854 con->in_msg->con = con->ops->get(con);
2855 BUG_ON(con->in_msg->con == NULL);
2856 } else {
2857 /*
2858 * Null message pointer means either we should skip
2859 * this message or we couldn't allocate memory. The
2860 * former is not an error.
2861 */
2862 if (*skip)
2863 return 0;
2864 con->error_msg = "error allocating memory for incoming message";
2865
2866 return -ENOMEM;
2867 }
2868 memcpy(&con->in_msg->hdr, &con->in_hdr, sizeof(con->in_hdr));
2869
2870 if (middle_len && !con->in_msg->middle) {
2871 ret = ceph_alloc_middle(con, con->in_msg);
2872 if (ret < 0) {
2873 ceph_msg_put(con->in_msg);
2874 con->in_msg = NULL;
2875 }
2876 }
2877
2878 return ret;
2879}
2880
2881
2882/*
2883 * Free a generically kmalloc'd message.
2884 */
2885void ceph_msg_kfree(struct ceph_msg *m)
2886{
2887 dout("msg_kfree %p\n", m);
2888 if (m->front_is_vmalloc)
2889 vfree(m->front.iov_base);
2890 else
2891 kfree(m->front.iov_base);
2892 kfree(m);
2893}
2894
2895/*
2896 * Drop a msg ref. Destroy as needed.
2897 */
2898void ceph_msg_last_put(struct kref *kref)
2899{
2900 struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
2901
2902 dout("ceph_msg_put last one on %p\n", m);
2903 WARN_ON(!list_empty(&m->list_head));
2904
2905 /* drop middle, data, if any */
2906 if (m->middle) {
2907 ceph_buffer_put(m->middle);
2908 m->middle = NULL;
2909 }
2910 m->length = 0;
2911 m->pages = NULL;
2912
2913 if (m->pagelist) {
2914 ceph_pagelist_release(m->pagelist);
2915 kfree(m->pagelist);
2916 m->pagelist = NULL;
2917 }
2918
2919 m->trail = NULL;
2920
2921 if (m->pool)
2922 ceph_msgpool_put(m->pool, m);
2923 else
2924 ceph_msg_kfree(m);
2925}
2926EXPORT_SYMBOL(ceph_msg_last_put);
2927
2928void ceph_msg_dump(struct ceph_msg *msg)
2929{
2930 pr_debug("msg_dump %p (front_max %d length %zd)\n", msg,
2931 msg->front_max, msg->length);
2932 print_hex_dump(KERN_DEBUG, "header: ",
2933 DUMP_PREFIX_OFFSET, 16, 1,
2934 &msg->hdr, sizeof(msg->hdr), true);
2935 print_hex_dump(KERN_DEBUG, " front: ",
2936 DUMP_PREFIX_OFFSET, 16, 1,
2937 msg->front.iov_base, msg->front.iov_len, true);
2938 if (msg->middle)
2939 print_hex_dump(KERN_DEBUG, "middle: ",
2940 DUMP_PREFIX_OFFSET, 16, 1,
2941 msg->middle->vec.iov_base,
2942 msg->middle->vec.iov_len, true);
2943 print_hex_dump(KERN_DEBUG, "footer: ",
2944 DUMP_PREFIX_OFFSET, 16, 1,
2945 &msg->footer, sizeof(msg->footer), true);
2946}
2947EXPORT_SYMBOL(ceph_msg_dump);