libceph: fix TAG_WAIT case
[linux-2.6.git] / net / ceph / messenger.c
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 #include <linux/bio.h>
13 #include <linux/blkdev.h>
14 #include <net/tcp.h>
15
16 #include <linux/ceph/libceph.h>
17 #include <linux/ceph/messenger.h>
18 #include <linux/ceph/decode.h>
19 #include <linux/ceph/pagelist.h>
20
21 /*
22  * Ceph uses the messenger to exchange ceph_msg messages with other
23  * hosts in the system.  The messenger provides ordered and reliable
24  * delivery.  We tolerate TCP disconnects by reconnecting (with
25  * exponential backoff) in the case of a fault (disconnection, bad
26  * crc, protocol error).  Acks allow sent messages to be discarded by
27  * the sender.
28  */
29
30 /* static tag bytes (protocol control messages) */
31 static char tag_msg = CEPH_MSGR_TAG_MSG;
32 static char tag_ack = CEPH_MSGR_TAG_ACK;
33 static char tag_keepalive = CEPH_MSGR_TAG_KEEPALIVE;
34
35 #ifdef CONFIG_LOCKDEP
36 static struct lock_class_key socket_class;
37 #endif
38
39
40 static void queue_con(struct ceph_connection *con);
41 static void con_work(struct work_struct *);
42 static void ceph_fault(struct ceph_connection *con);
43
44 /*
45  * nicely render a sockaddr as a string.
46  */
47 #define MAX_ADDR_STR 20
48 #define MAX_ADDR_STR_LEN 60
49 static char addr_str[MAX_ADDR_STR][MAX_ADDR_STR_LEN];
50 static DEFINE_SPINLOCK(addr_str_lock);
51 static int last_addr_str;
52
53 const char *ceph_pr_addr(const struct sockaddr_storage *ss)
54 {
55         int i;
56         char *s;
57         struct sockaddr_in *in4 = (void *)ss;
58         struct sockaddr_in6 *in6 = (void *)ss;
59
60         spin_lock(&addr_str_lock);
61         i = last_addr_str++;
62         if (last_addr_str == MAX_ADDR_STR)
63                 last_addr_str = 0;
64         spin_unlock(&addr_str_lock);
65         s = addr_str[i];
66
67         switch (ss->ss_family) {
68         case AF_INET:
69                 snprintf(s, MAX_ADDR_STR_LEN, "%pI4:%u", &in4->sin_addr,
70                          (unsigned int)ntohs(in4->sin_port));
71                 break;
72
73         case AF_INET6:
74                 snprintf(s, MAX_ADDR_STR_LEN, "[%pI6c]:%u", &in6->sin6_addr,
75                          (unsigned int)ntohs(in6->sin6_port));
76                 break;
77
78         default:
79                 snprintf(s, MAX_ADDR_STR_LEN, "(unknown sockaddr family %d)",
80                          (int)ss->ss_family);
81         }
82
83         return s;
84 }
85 EXPORT_SYMBOL(ceph_pr_addr);
86
87 static void encode_my_addr(struct ceph_messenger *msgr)
88 {
89         memcpy(&msgr->my_enc_addr, &msgr->inst.addr, sizeof(msgr->my_enc_addr));
90         ceph_encode_addr(&msgr->my_enc_addr);
91 }
92
93 /*
94  * work queue for all reading and writing to/from the socket.
95  */
96 struct workqueue_struct *ceph_msgr_wq;
97
98 int ceph_msgr_init(void)
99 {
100         ceph_msgr_wq = alloc_workqueue("ceph-msgr", WQ_NON_REENTRANT, 0);
101         if (!ceph_msgr_wq) {
102                 pr_err("msgr_init failed to create workqueue\n");
103                 return -ENOMEM;
104         }
105         return 0;
106 }
107 EXPORT_SYMBOL(ceph_msgr_init);
108
109 void ceph_msgr_exit(void)
110 {
111         destroy_workqueue(ceph_msgr_wq);
112 }
113 EXPORT_SYMBOL(ceph_msgr_exit);
114
115 void ceph_msgr_flush(void)
116 {
117         flush_workqueue(ceph_msgr_wq);
118 }
119 EXPORT_SYMBOL(ceph_msgr_flush);
120
121
122 /*
123  * socket callback functions
124  */
125
126 /* data available on socket, or listen socket received a connect */
127 static void ceph_data_ready(struct sock *sk, int count_unused)
128 {
129         struct ceph_connection *con =
130                 (struct ceph_connection *)sk->sk_user_data;
131         if (sk->sk_state != TCP_CLOSE_WAIT) {
132                 dout("ceph_data_ready on %p state = %lu, queueing work\n",
133                      con, con->state);
134                 queue_con(con);
135         }
136 }
137
138 /* socket has buffer space for writing */
139 static void ceph_write_space(struct sock *sk)
140 {
141         struct ceph_connection *con =
142                 (struct ceph_connection *)sk->sk_user_data;
143
144         /* only queue to workqueue if there is data we want to write. */
145         if (test_bit(WRITE_PENDING, &con->state)) {
146                 dout("ceph_write_space %p queueing write work\n", con);
147                 queue_con(con);
148         } else {
149                 dout("ceph_write_space %p nothing to write\n", con);
150         }
151
152         /* since we have our own write_space, clear the SOCK_NOSPACE flag */
153         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
154 }
155
156 /* socket's state has changed */
157 static void ceph_state_change(struct sock *sk)
158 {
159         struct ceph_connection *con =
160                 (struct ceph_connection *)sk->sk_user_data;
161
162         dout("ceph_state_change %p state = %lu sk_state = %u\n",
163              con, con->state, sk->sk_state);
164
165         if (test_bit(CLOSED, &con->state))
166                 return;
167
168         switch (sk->sk_state) {
169         case TCP_CLOSE:
170                 dout("ceph_state_change TCP_CLOSE\n");
171         case TCP_CLOSE_WAIT:
172                 dout("ceph_state_change TCP_CLOSE_WAIT\n");
173                 if (test_and_set_bit(SOCK_CLOSED, &con->state) == 0) {
174                         if (test_bit(CONNECTING, &con->state))
175                                 con->error_msg = "connection failed";
176                         else
177                                 con->error_msg = "socket closed";
178                         queue_con(con);
179                 }
180                 break;
181         case TCP_ESTABLISHED:
182                 dout("ceph_state_change TCP_ESTABLISHED\n");
183                 queue_con(con);
184                 break;
185         }
186 }
187
188 /*
189  * set up socket callbacks
190  */
191 static void set_sock_callbacks(struct socket *sock,
192                                struct ceph_connection *con)
193 {
194         struct sock *sk = sock->sk;
195         sk->sk_user_data = (void *)con;
196         sk->sk_data_ready = ceph_data_ready;
197         sk->sk_write_space = ceph_write_space;
198         sk->sk_state_change = ceph_state_change;
199 }
200
201
202 /*
203  * socket helpers
204  */
205
206 /*
207  * initiate connection to a remote socket.
208  */
209 static struct socket *ceph_tcp_connect(struct ceph_connection *con)
210 {
211         struct sockaddr_storage *paddr = &con->peer_addr.in_addr;
212         struct socket *sock;
213         int ret;
214
215         BUG_ON(con->sock);
216         ret = sock_create_kern(con->peer_addr.in_addr.ss_family, SOCK_STREAM,
217                                IPPROTO_TCP, &sock);
218         if (ret)
219                 return ERR_PTR(ret);
220         con->sock = sock;
221         sock->sk->sk_allocation = GFP_NOFS;
222
223 #ifdef CONFIG_LOCKDEP
224         lockdep_set_class(&sock->sk->sk_lock, &socket_class);
225 #endif
226
227         set_sock_callbacks(sock, con);
228
229         dout("connect %s\n", ceph_pr_addr(&con->peer_addr.in_addr));
230
231         ret = sock->ops->connect(sock, (struct sockaddr *)paddr, sizeof(*paddr),
232                                  O_NONBLOCK);
233         if (ret == -EINPROGRESS) {
234                 dout("connect %s EINPROGRESS sk_state = %u\n",
235                      ceph_pr_addr(&con->peer_addr.in_addr),
236                      sock->sk->sk_state);
237                 ret = 0;
238         }
239         if (ret < 0) {
240                 pr_err("connect %s error %d\n",
241                        ceph_pr_addr(&con->peer_addr.in_addr), ret);
242                 sock_release(sock);
243                 con->sock = NULL;
244                 con->error_msg = "connect error";
245         }
246
247         if (ret < 0)
248                 return ERR_PTR(ret);
249         return sock;
250 }
251
252 static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
253 {
254         struct kvec iov = {buf, len};
255         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
256         int r;
257
258         r = kernel_recvmsg(sock, &msg, &iov, 1, len, msg.msg_flags);
259         if (r == -EAGAIN)
260                 r = 0;
261         return r;
262 }
263
264 /*
265  * write something.  @more is true if caller will be sending more data
266  * shortly.
267  */
268 static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov,
269                      size_t kvlen, size_t len, int more)
270 {
271         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
272         int r;
273
274         if (more)
275                 msg.msg_flags |= MSG_MORE;
276         else
277                 msg.msg_flags |= MSG_EOR;  /* superfluous, but what the hell */
278
279         r = kernel_sendmsg(sock, &msg, iov, kvlen, len);
280         if (r == -EAGAIN)
281                 r = 0;
282         return r;
283 }
284
285
286 /*
287  * Shutdown/close the socket for the given connection.
288  */
289 static int con_close_socket(struct ceph_connection *con)
290 {
291         int rc;
292
293         dout("con_close_socket on %p sock %p\n", con, con->sock);
294         if (!con->sock)
295                 return 0;
296         set_bit(SOCK_CLOSED, &con->state);
297         rc = con->sock->ops->shutdown(con->sock, SHUT_RDWR);
298         sock_release(con->sock);
299         con->sock = NULL;
300         clear_bit(SOCK_CLOSED, &con->state);
301         return rc;
302 }
303
304 /*
305  * Reset a connection.  Discard all incoming and outgoing messages
306  * and clear *_seq state.
307  */
308 static void ceph_msg_remove(struct ceph_msg *msg)
309 {
310         list_del_init(&msg->list_head);
311         ceph_msg_put(msg);
312 }
313 static void ceph_msg_remove_list(struct list_head *head)
314 {
315         while (!list_empty(head)) {
316                 struct ceph_msg *msg = list_first_entry(head, struct ceph_msg,
317                                                         list_head);
318                 ceph_msg_remove(msg);
319         }
320 }
321
322 static void reset_connection(struct ceph_connection *con)
323 {
324         /* reset connection, out_queue, msg_ and connect_seq */
325         /* discard existing out_queue and msg_seq */
326         ceph_msg_remove_list(&con->out_queue);
327         ceph_msg_remove_list(&con->out_sent);
328
329         if (con->in_msg) {
330                 ceph_msg_put(con->in_msg);
331                 con->in_msg = NULL;
332         }
333
334         con->connect_seq = 0;
335         con->out_seq = 0;
336         if (con->out_msg) {
337                 ceph_msg_put(con->out_msg);
338                 con->out_msg = NULL;
339         }
340         con->in_seq = 0;
341         con->in_seq_acked = 0;
342 }
343
344 /*
345  * mark a peer down.  drop any open connections.
346  */
347 void ceph_con_close(struct ceph_connection *con)
348 {
349         dout("con_close %p peer %s\n", con,
350              ceph_pr_addr(&con->peer_addr.in_addr));
351         set_bit(CLOSED, &con->state);  /* in case there's queued work */
352         clear_bit(STANDBY, &con->state);  /* avoid connect_seq bump */
353         clear_bit(LOSSYTX, &con->state);  /* so we retry next connect */
354         clear_bit(KEEPALIVE_PENDING, &con->state);
355         clear_bit(WRITE_PENDING, &con->state);
356         mutex_lock(&con->mutex);
357         reset_connection(con);
358         con->peer_global_seq = 0;
359         cancel_delayed_work(&con->work);
360         mutex_unlock(&con->mutex);
361         queue_con(con);
362 }
363 EXPORT_SYMBOL(ceph_con_close);
364
365 /*
366  * Reopen a closed connection, with a new peer address.
367  */
368 void ceph_con_open(struct ceph_connection *con, struct ceph_entity_addr *addr)
369 {
370         dout("con_open %p %s\n", con, ceph_pr_addr(&addr->in_addr));
371         set_bit(OPENING, &con->state);
372         clear_bit(CLOSED, &con->state);
373         memcpy(&con->peer_addr, addr, sizeof(*addr));
374         con->delay = 0;      /* reset backoff memory */
375         queue_con(con);
376 }
377 EXPORT_SYMBOL(ceph_con_open);
378
379 /*
380  * return true if this connection ever successfully opened
381  */
382 bool ceph_con_opened(struct ceph_connection *con)
383 {
384         return con->connect_seq > 0;
385 }
386
387 /*
388  * generic get/put
389  */
390 struct ceph_connection *ceph_con_get(struct ceph_connection *con)
391 {
392         dout("con_get %p nref = %d -> %d\n", con,
393              atomic_read(&con->nref), atomic_read(&con->nref) + 1);
394         if (atomic_inc_not_zero(&con->nref))
395                 return con;
396         return NULL;
397 }
398
399 void ceph_con_put(struct ceph_connection *con)
400 {
401         dout("con_put %p nref = %d -> %d\n", con,
402              atomic_read(&con->nref), atomic_read(&con->nref) - 1);
403         BUG_ON(atomic_read(&con->nref) == 0);
404         if (atomic_dec_and_test(&con->nref)) {
405                 BUG_ON(con->sock);
406                 kfree(con);
407         }
408 }
409
410 /*
411  * initialize a new connection.
412  */
413 void ceph_con_init(struct ceph_messenger *msgr, struct ceph_connection *con)
414 {
415         dout("con_init %p\n", con);
416         memset(con, 0, sizeof(*con));
417         atomic_set(&con->nref, 1);
418         con->msgr = msgr;
419         mutex_init(&con->mutex);
420         INIT_LIST_HEAD(&con->out_queue);
421         INIT_LIST_HEAD(&con->out_sent);
422         INIT_DELAYED_WORK(&con->work, con_work);
423 }
424 EXPORT_SYMBOL(ceph_con_init);
425
426
427 /*
428  * We maintain a global counter to order connection attempts.  Get
429  * a unique seq greater than @gt.
430  */
431 static u32 get_global_seq(struct ceph_messenger *msgr, u32 gt)
432 {
433         u32 ret;
434
435         spin_lock(&msgr->global_seq_lock);
436         if (msgr->global_seq < gt)
437                 msgr->global_seq = gt;
438         ret = ++msgr->global_seq;
439         spin_unlock(&msgr->global_seq_lock);
440         return ret;
441 }
442
443
444 /*
445  * Prepare footer for currently outgoing message, and finish things
446  * off.  Assumes out_kvec* are already valid.. we just add on to the end.
447  */
448 static void prepare_write_message_footer(struct ceph_connection *con, int v)
449 {
450         struct ceph_msg *m = con->out_msg;
451
452         dout("prepare_write_message_footer %p\n", con);
453         con->out_kvec_is_msg = true;
454         con->out_kvec[v].iov_base = &m->footer;
455         con->out_kvec[v].iov_len = sizeof(m->footer);
456         con->out_kvec_bytes += sizeof(m->footer);
457         con->out_kvec_left++;
458         con->out_more = m->more_to_follow;
459         con->out_msg_done = true;
460 }
461
462 /*
463  * Prepare headers for the next outgoing message.
464  */
465 static void prepare_write_message(struct ceph_connection *con)
466 {
467         struct ceph_msg *m;
468         int v = 0;
469
470         con->out_kvec_bytes = 0;
471         con->out_kvec_is_msg = true;
472         con->out_msg_done = false;
473
474         /* Sneak an ack in there first?  If we can get it into the same
475          * TCP packet that's a good thing. */
476         if (con->in_seq > con->in_seq_acked) {
477                 con->in_seq_acked = con->in_seq;
478                 con->out_kvec[v].iov_base = &tag_ack;
479                 con->out_kvec[v++].iov_len = 1;
480                 con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
481                 con->out_kvec[v].iov_base = &con->out_temp_ack;
482                 con->out_kvec[v++].iov_len = sizeof(con->out_temp_ack);
483                 con->out_kvec_bytes = 1 + sizeof(con->out_temp_ack);
484         }
485
486         m = list_first_entry(&con->out_queue,
487                        struct ceph_msg, list_head);
488         con->out_msg = m;
489         if (test_bit(LOSSYTX, &con->state)) {
490                 list_del_init(&m->list_head);
491         } else {
492                 /* put message on sent list */
493                 ceph_msg_get(m);
494                 list_move_tail(&m->list_head, &con->out_sent);
495         }
496
497         /*
498          * only assign outgoing seq # if we haven't sent this message
499          * yet.  if it is requeued, resend with it's original seq.
500          */
501         if (m->needs_out_seq) {
502                 m->hdr.seq = cpu_to_le64(++con->out_seq);
503                 m->needs_out_seq = false;
504         }
505
506         dout("prepare_write_message %p seq %lld type %d len %d+%d+%d %d pgs\n",
507              m, con->out_seq, le16_to_cpu(m->hdr.type),
508              le32_to_cpu(m->hdr.front_len), le32_to_cpu(m->hdr.middle_len),
509              le32_to_cpu(m->hdr.data_len),
510              m->nr_pages);
511         BUG_ON(le32_to_cpu(m->hdr.front_len) != m->front.iov_len);
512
513         /* tag + hdr + front + middle */
514         con->out_kvec[v].iov_base = &tag_msg;
515         con->out_kvec[v++].iov_len = 1;
516         con->out_kvec[v].iov_base = &m->hdr;
517         con->out_kvec[v++].iov_len = sizeof(m->hdr);
518         con->out_kvec[v++] = m->front;
519         if (m->middle)
520                 con->out_kvec[v++] = m->middle->vec;
521         con->out_kvec_left = v;
522         con->out_kvec_bytes += 1 + sizeof(m->hdr) + m->front.iov_len +
523                 (m->middle ? m->middle->vec.iov_len : 0);
524         con->out_kvec_cur = con->out_kvec;
525
526         /* fill in crc (except data pages), footer */
527         con->out_msg->hdr.crc =
528                 cpu_to_le32(crc32c(0, (void *)&m->hdr,
529                                       sizeof(m->hdr) - sizeof(m->hdr.crc)));
530         con->out_msg->footer.flags = CEPH_MSG_FOOTER_COMPLETE;
531         con->out_msg->footer.front_crc =
532                 cpu_to_le32(crc32c(0, m->front.iov_base, m->front.iov_len));
533         if (m->middle)
534                 con->out_msg->footer.middle_crc =
535                         cpu_to_le32(crc32c(0, m->middle->vec.iov_base,
536                                            m->middle->vec.iov_len));
537         else
538                 con->out_msg->footer.middle_crc = 0;
539         con->out_msg->footer.data_crc = 0;
540         dout("prepare_write_message front_crc %u data_crc %u\n",
541              le32_to_cpu(con->out_msg->footer.front_crc),
542              le32_to_cpu(con->out_msg->footer.middle_crc));
543
544         /* is there a data payload? */
545         if (le32_to_cpu(m->hdr.data_len) > 0) {
546                 /* initialize page iterator */
547                 con->out_msg_pos.page = 0;
548                 if (m->pages)
549                         con->out_msg_pos.page_pos = m->page_alignment;
550                 else
551                         con->out_msg_pos.page_pos = 0;
552                 con->out_msg_pos.data_pos = 0;
553                 con->out_msg_pos.did_page_crc = 0;
554                 con->out_more = 1;  /* data + footer will follow */
555         } else {
556                 /* no, queue up footer too and be done */
557                 prepare_write_message_footer(con, v);
558         }
559
560         set_bit(WRITE_PENDING, &con->state);
561 }
562
563 /*
564  * Prepare an ack.
565  */
566 static void prepare_write_ack(struct ceph_connection *con)
567 {
568         dout("prepare_write_ack %p %llu -> %llu\n", con,
569              con->in_seq_acked, con->in_seq);
570         con->in_seq_acked = con->in_seq;
571
572         con->out_kvec[0].iov_base = &tag_ack;
573         con->out_kvec[0].iov_len = 1;
574         con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
575         con->out_kvec[1].iov_base = &con->out_temp_ack;
576         con->out_kvec[1].iov_len = sizeof(con->out_temp_ack);
577         con->out_kvec_left = 2;
578         con->out_kvec_bytes = 1 + sizeof(con->out_temp_ack);
579         con->out_kvec_cur = con->out_kvec;
580         con->out_more = 1;  /* more will follow.. eventually.. */
581         set_bit(WRITE_PENDING, &con->state);
582 }
583
584 /*
585  * Prepare to write keepalive byte.
586  */
587 static void prepare_write_keepalive(struct ceph_connection *con)
588 {
589         dout("prepare_write_keepalive %p\n", con);
590         con->out_kvec[0].iov_base = &tag_keepalive;
591         con->out_kvec[0].iov_len = 1;
592         con->out_kvec_left = 1;
593         con->out_kvec_bytes = 1;
594         con->out_kvec_cur = con->out_kvec;
595         set_bit(WRITE_PENDING, &con->state);
596 }
597
598 /*
599  * Connection negotiation.
600  */
601
602 static int prepare_connect_authorizer(struct ceph_connection *con)
603 {
604         void *auth_buf;
605         int auth_len = 0;
606         int auth_protocol = 0;
607
608         mutex_unlock(&con->mutex);
609         if (con->ops->get_authorizer)
610                 con->ops->get_authorizer(con, &auth_buf, &auth_len,
611                                          &auth_protocol, &con->auth_reply_buf,
612                                          &con->auth_reply_buf_len,
613                                          con->auth_retry);
614         mutex_lock(&con->mutex);
615
616         if (test_bit(CLOSED, &con->state) ||
617             test_bit(OPENING, &con->state))
618                 return -EAGAIN;
619
620         con->out_connect.authorizer_protocol = cpu_to_le32(auth_protocol);
621         con->out_connect.authorizer_len = cpu_to_le32(auth_len);
622
623         if (auth_len) {
624                 con->out_kvec[con->out_kvec_left].iov_base = auth_buf;
625                 con->out_kvec[con->out_kvec_left].iov_len = auth_len;
626                 con->out_kvec_left++;
627                 con->out_kvec_bytes += auth_len;
628         }
629         return 0;
630 }
631
632 /*
633  * We connected to a peer and are saying hello.
634  */
635 static void prepare_write_banner(struct ceph_messenger *msgr,
636                                  struct ceph_connection *con)
637 {
638         int len = strlen(CEPH_BANNER);
639
640         con->out_kvec[0].iov_base = CEPH_BANNER;
641         con->out_kvec[0].iov_len = len;
642         con->out_kvec[1].iov_base = &msgr->my_enc_addr;
643         con->out_kvec[1].iov_len = sizeof(msgr->my_enc_addr);
644         con->out_kvec_left = 2;
645         con->out_kvec_bytes = len + sizeof(msgr->my_enc_addr);
646         con->out_kvec_cur = con->out_kvec;
647         con->out_more = 0;
648         set_bit(WRITE_PENDING, &con->state);
649 }
650
651 static int prepare_write_connect(struct ceph_messenger *msgr,
652                                  struct ceph_connection *con,
653                                  int after_banner)
654 {
655         unsigned global_seq = get_global_seq(con->msgr, 0);
656         int proto;
657
658         switch (con->peer_name.type) {
659         case CEPH_ENTITY_TYPE_MON:
660                 proto = CEPH_MONC_PROTOCOL;
661                 break;
662         case CEPH_ENTITY_TYPE_OSD:
663                 proto = CEPH_OSDC_PROTOCOL;
664                 break;
665         case CEPH_ENTITY_TYPE_MDS:
666                 proto = CEPH_MDSC_PROTOCOL;
667                 break;
668         default:
669                 BUG();
670         }
671
672         dout("prepare_write_connect %p cseq=%d gseq=%d proto=%d\n", con,
673              con->connect_seq, global_seq, proto);
674
675         con->out_connect.features = cpu_to_le64(msgr->supported_features);
676         con->out_connect.host_type = cpu_to_le32(CEPH_ENTITY_TYPE_CLIENT);
677         con->out_connect.connect_seq = cpu_to_le32(con->connect_seq);
678         con->out_connect.global_seq = cpu_to_le32(global_seq);
679         con->out_connect.protocol_version = cpu_to_le32(proto);
680         con->out_connect.flags = 0;
681
682         if (!after_banner) {
683                 con->out_kvec_left = 0;
684                 con->out_kvec_bytes = 0;
685         }
686         con->out_kvec[con->out_kvec_left].iov_base = &con->out_connect;
687         con->out_kvec[con->out_kvec_left].iov_len = sizeof(con->out_connect);
688         con->out_kvec_left++;
689         con->out_kvec_bytes += sizeof(con->out_connect);
690         con->out_kvec_cur = con->out_kvec;
691         con->out_more = 0;
692         set_bit(WRITE_PENDING, &con->state);
693
694         return prepare_connect_authorizer(con);
695 }
696
697
698 /*
699  * write as much of pending kvecs to the socket as we can.
700  *  1 -> done
701  *  0 -> socket full, but more to do
702  * <0 -> error
703  */
704 static int write_partial_kvec(struct ceph_connection *con)
705 {
706         int ret;
707
708         dout("write_partial_kvec %p %d left\n", con, con->out_kvec_bytes);
709         while (con->out_kvec_bytes > 0) {
710                 ret = ceph_tcp_sendmsg(con->sock, con->out_kvec_cur,
711                                        con->out_kvec_left, con->out_kvec_bytes,
712                                        con->out_more);
713                 if (ret <= 0)
714                         goto out;
715                 con->out_kvec_bytes -= ret;
716                 if (con->out_kvec_bytes == 0)
717                         break;            /* done */
718                 while (ret > 0) {
719                         if (ret >= con->out_kvec_cur->iov_len) {
720                                 ret -= con->out_kvec_cur->iov_len;
721                                 con->out_kvec_cur++;
722                                 con->out_kvec_left--;
723                         } else {
724                                 con->out_kvec_cur->iov_len -= ret;
725                                 con->out_kvec_cur->iov_base += ret;
726                                 ret = 0;
727                                 break;
728                         }
729                 }
730         }
731         con->out_kvec_left = 0;
732         con->out_kvec_is_msg = false;
733         ret = 1;
734 out:
735         dout("write_partial_kvec %p %d left in %d kvecs ret = %d\n", con,
736              con->out_kvec_bytes, con->out_kvec_left, ret);
737         return ret;  /* done! */
738 }
739
740 #ifdef CONFIG_BLOCK
741 static void init_bio_iter(struct bio *bio, struct bio **iter, int *seg)
742 {
743         if (!bio) {
744                 *iter = NULL;
745                 *seg = 0;
746                 return;
747         }
748         *iter = bio;
749         *seg = bio->bi_idx;
750 }
751
752 static void iter_bio_next(struct bio **bio_iter, int *seg)
753 {
754         if (*bio_iter == NULL)
755                 return;
756
757         BUG_ON(*seg >= (*bio_iter)->bi_vcnt);
758
759         (*seg)++;
760         if (*seg == (*bio_iter)->bi_vcnt)
761                 init_bio_iter((*bio_iter)->bi_next, bio_iter, seg);
762 }
763 #endif
764
765 /*
766  * Write as much message data payload as we can.  If we finish, queue
767  * up the footer.
768  *  1 -> done, footer is now queued in out_kvec[].
769  *  0 -> socket full, but more to do
770  * <0 -> error
771  */
772 static int write_partial_msg_pages(struct ceph_connection *con)
773 {
774         struct ceph_msg *msg = con->out_msg;
775         unsigned data_len = le32_to_cpu(msg->hdr.data_len);
776         size_t len;
777         int crc = con->msgr->nocrc;
778         int ret;
779         int total_max_write;
780         int in_trail = 0;
781         size_t trail_len = (msg->trail ? msg->trail->length : 0);
782
783         dout("write_partial_msg_pages %p msg %p page %d/%d offset %d\n",
784              con, con->out_msg, con->out_msg_pos.page, con->out_msg->nr_pages,
785              con->out_msg_pos.page_pos);
786
787 #ifdef CONFIG_BLOCK
788         if (msg->bio && !msg->bio_iter)
789                 init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
790 #endif
791
792         while (data_len > con->out_msg_pos.data_pos) {
793                 struct page *page = NULL;
794                 void *kaddr = NULL;
795                 int max_write = PAGE_SIZE;
796                 int page_shift = 0;
797
798                 total_max_write = data_len - trail_len -
799                         con->out_msg_pos.data_pos;
800
801                 /*
802                  * if we are calculating the data crc (the default), we need
803                  * to map the page.  if our pages[] has been revoked, use the
804                  * zero page.
805                  */
806
807                 /* have we reached the trail part of the data? */
808                 if (con->out_msg_pos.data_pos >= data_len - trail_len) {
809                         in_trail = 1;
810
811                         total_max_write = data_len - con->out_msg_pos.data_pos;
812
813                         page = list_first_entry(&msg->trail->head,
814                                                 struct page, lru);
815                         if (crc)
816                                 kaddr = kmap(page);
817                         max_write = PAGE_SIZE;
818                 } else if (msg->pages) {
819                         page = msg->pages[con->out_msg_pos.page];
820                         if (crc)
821                                 kaddr = kmap(page);
822                 } else if (msg->pagelist) {
823                         page = list_first_entry(&msg->pagelist->head,
824                                                 struct page, lru);
825                         if (crc)
826                                 kaddr = kmap(page);
827 #ifdef CONFIG_BLOCK
828                 } else if (msg->bio) {
829                         struct bio_vec *bv;
830
831                         bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
832                         page = bv->bv_page;
833                         page_shift = bv->bv_offset;
834                         if (crc)
835                                 kaddr = kmap(page) + page_shift;
836                         max_write = bv->bv_len;
837 #endif
838                 } else {
839                         page = con->msgr->zero_page;
840                         if (crc)
841                                 kaddr = page_address(con->msgr->zero_page);
842                 }
843                 len = min_t(int, max_write - con->out_msg_pos.page_pos,
844                             total_max_write);
845
846                 if (crc && !con->out_msg_pos.did_page_crc) {
847                         void *base = kaddr + con->out_msg_pos.page_pos;
848                         u32 tmpcrc = le32_to_cpu(con->out_msg->footer.data_crc);
849
850                         BUG_ON(kaddr == NULL);
851                         con->out_msg->footer.data_crc =
852                                 cpu_to_le32(crc32c(tmpcrc, base, len));
853                         con->out_msg_pos.did_page_crc = 1;
854                 }
855                 ret = kernel_sendpage(con->sock, page,
856                                       con->out_msg_pos.page_pos + page_shift,
857                                       len,
858                                       MSG_DONTWAIT | MSG_NOSIGNAL |
859                                       MSG_MORE);
860
861                 if (crc &&
862                     (msg->pages || msg->pagelist || msg->bio || in_trail))
863                         kunmap(page);
864
865                 if (ret == -EAGAIN)
866                         ret = 0;
867                 if (ret <= 0)
868                         goto out;
869
870                 con->out_msg_pos.data_pos += ret;
871                 con->out_msg_pos.page_pos += ret;
872                 if (ret == len) {
873                         con->out_msg_pos.page_pos = 0;
874                         con->out_msg_pos.page++;
875                         con->out_msg_pos.did_page_crc = 0;
876                         if (in_trail)
877                                 list_move_tail(&page->lru,
878                                                &msg->trail->head);
879                         else if (msg->pagelist)
880                                 list_move_tail(&page->lru,
881                                                &msg->pagelist->head);
882 #ifdef CONFIG_BLOCK
883                         else if (msg->bio)
884                                 iter_bio_next(&msg->bio_iter, &msg->bio_seg);
885 #endif
886                 }
887         }
888
889         dout("write_partial_msg_pages %p msg %p done\n", con, msg);
890
891         /* prepare and queue up footer, too */
892         if (!crc)
893                 con->out_msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
894         con->out_kvec_bytes = 0;
895         con->out_kvec_left = 0;
896         con->out_kvec_cur = con->out_kvec;
897         prepare_write_message_footer(con, 0);
898         ret = 1;
899 out:
900         return ret;
901 }
902
903 /*
904  * write some zeros
905  */
906 static int write_partial_skip(struct ceph_connection *con)
907 {
908         int ret;
909
910         while (con->out_skip > 0) {
911                 struct kvec iov = {
912                         .iov_base = page_address(con->msgr->zero_page),
913                         .iov_len = min(con->out_skip, (int)PAGE_CACHE_SIZE)
914                 };
915
916                 ret = ceph_tcp_sendmsg(con->sock, &iov, 1, iov.iov_len, 1);
917                 if (ret <= 0)
918                         goto out;
919                 con->out_skip -= ret;
920         }
921         ret = 1;
922 out:
923         return ret;
924 }
925
926 /*
927  * Prepare to read connection handshake, or an ack.
928  */
929 static void prepare_read_banner(struct ceph_connection *con)
930 {
931         dout("prepare_read_banner %p\n", con);
932         con->in_base_pos = 0;
933 }
934
935 static void prepare_read_connect(struct ceph_connection *con)
936 {
937         dout("prepare_read_connect %p\n", con);
938         con->in_base_pos = 0;
939 }
940
941 static void prepare_read_ack(struct ceph_connection *con)
942 {
943         dout("prepare_read_ack %p\n", con);
944         con->in_base_pos = 0;
945 }
946
947 static void prepare_read_tag(struct ceph_connection *con)
948 {
949         dout("prepare_read_tag %p\n", con);
950         con->in_base_pos = 0;
951         con->in_tag = CEPH_MSGR_TAG_READY;
952 }
953
954 /*
955  * Prepare to read a message.
956  */
957 static int prepare_read_message(struct ceph_connection *con)
958 {
959         dout("prepare_read_message %p\n", con);
960         BUG_ON(con->in_msg != NULL);
961         con->in_base_pos = 0;
962         con->in_front_crc = con->in_middle_crc = con->in_data_crc = 0;
963         return 0;
964 }
965
966
967 static int read_partial(struct ceph_connection *con,
968                         int *to, int size, void *object)
969 {
970         *to += size;
971         while (con->in_base_pos < *to) {
972                 int left = *to - con->in_base_pos;
973                 int have = size - left;
974                 int ret = ceph_tcp_recvmsg(con->sock, object + have, left);
975                 if (ret <= 0)
976                         return ret;
977                 con->in_base_pos += ret;
978         }
979         return 1;
980 }
981
982
983 /*
984  * Read all or part of the connect-side handshake on a new connection
985  */
986 static int read_partial_banner(struct ceph_connection *con)
987 {
988         int ret, to = 0;
989
990         dout("read_partial_banner %p at %d\n", con, con->in_base_pos);
991
992         /* peer's banner */
993         ret = read_partial(con, &to, strlen(CEPH_BANNER), con->in_banner);
994         if (ret <= 0)
995                 goto out;
996         ret = read_partial(con, &to, sizeof(con->actual_peer_addr),
997                            &con->actual_peer_addr);
998         if (ret <= 0)
999                 goto out;
1000         ret = read_partial(con, &to, sizeof(con->peer_addr_for_me),
1001                            &con->peer_addr_for_me);
1002         if (ret <= 0)
1003                 goto out;
1004 out:
1005         return ret;
1006 }
1007
1008 static int read_partial_connect(struct ceph_connection *con)
1009 {
1010         int ret, to = 0;
1011
1012         dout("read_partial_connect %p at %d\n", con, con->in_base_pos);
1013
1014         ret = read_partial(con, &to, sizeof(con->in_reply), &con->in_reply);
1015         if (ret <= 0)
1016                 goto out;
1017         ret = read_partial(con, &to, le32_to_cpu(con->in_reply.authorizer_len),
1018                            con->auth_reply_buf);
1019         if (ret <= 0)
1020                 goto out;
1021
1022         dout("read_partial_connect %p tag %d, con_seq = %u, g_seq = %u\n",
1023              con, (int)con->in_reply.tag,
1024              le32_to_cpu(con->in_reply.connect_seq),
1025              le32_to_cpu(con->in_reply.global_seq));
1026 out:
1027         return ret;
1028
1029 }
1030
1031 /*
1032  * Verify the hello banner looks okay.
1033  */
1034 static int verify_hello(struct ceph_connection *con)
1035 {
1036         if (memcmp(con->in_banner, CEPH_BANNER, strlen(CEPH_BANNER))) {
1037                 pr_err("connect to %s got bad banner\n",
1038                        ceph_pr_addr(&con->peer_addr.in_addr));
1039                 con->error_msg = "protocol error, bad banner";
1040                 return -1;
1041         }
1042         return 0;
1043 }
1044
1045 static bool addr_is_blank(struct sockaddr_storage *ss)
1046 {
1047         switch (ss->ss_family) {
1048         case AF_INET:
1049                 return ((struct sockaddr_in *)ss)->sin_addr.s_addr == 0;
1050         case AF_INET6:
1051                 return
1052                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[0] == 0 &&
1053                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[1] == 0 &&
1054                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[2] == 0 &&
1055                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[3] == 0;
1056         }
1057         return false;
1058 }
1059
1060 static int addr_port(struct sockaddr_storage *ss)
1061 {
1062         switch (ss->ss_family) {
1063         case AF_INET:
1064                 return ntohs(((struct sockaddr_in *)ss)->sin_port);
1065         case AF_INET6:
1066                 return ntohs(((struct sockaddr_in6 *)ss)->sin6_port);
1067         }
1068         return 0;
1069 }
1070
1071 static void addr_set_port(struct sockaddr_storage *ss, int p)
1072 {
1073         switch (ss->ss_family) {
1074         case AF_INET:
1075                 ((struct sockaddr_in *)ss)->sin_port = htons(p);
1076         case AF_INET6:
1077                 ((struct sockaddr_in6 *)ss)->sin6_port = htons(p);
1078         }
1079 }
1080
1081 /*
1082  * Parse an ip[:port] list into an addr array.  Use the default
1083  * monitor port if a port isn't specified.
1084  */
1085 int ceph_parse_ips(const char *c, const char *end,
1086                    struct ceph_entity_addr *addr,
1087                    int max_count, int *count)
1088 {
1089         int i;
1090         const char *p = c;
1091
1092         dout("parse_ips on '%.*s'\n", (int)(end-c), c);
1093         for (i = 0; i < max_count; i++) {
1094                 const char *ipend;
1095                 struct sockaddr_storage *ss = &addr[i].in_addr;
1096                 struct sockaddr_in *in4 = (void *)ss;
1097                 struct sockaddr_in6 *in6 = (void *)ss;
1098                 int port;
1099                 char delim = ',';
1100
1101                 if (*p == '[') {
1102                         delim = ']';
1103                         p++;
1104                 }
1105
1106                 memset(ss, 0, sizeof(*ss));
1107                 if (in4_pton(p, end - p, (u8 *)&in4->sin_addr.s_addr,
1108                              delim, &ipend))
1109                         ss->ss_family = AF_INET;
1110                 else if (in6_pton(p, end - p, (u8 *)&in6->sin6_addr.s6_addr,
1111                                   delim, &ipend))
1112                         ss->ss_family = AF_INET6;
1113                 else
1114                         goto bad;
1115                 p = ipend;
1116
1117                 if (delim == ']') {
1118                         if (*p != ']') {
1119                                 dout("missing matching ']'\n");
1120                                 goto bad;
1121                         }
1122                         p++;
1123                 }
1124
1125                 /* port? */
1126                 if (p < end && *p == ':') {
1127                         port = 0;
1128                         p++;
1129                         while (p < end && *p >= '0' && *p <= '9') {
1130                                 port = (port * 10) + (*p - '0');
1131                                 p++;
1132                         }
1133                         if (port > 65535 || port == 0)
1134                                 goto bad;
1135                 } else {
1136                         port = CEPH_MON_PORT;
1137                 }
1138
1139                 addr_set_port(ss, port);
1140
1141                 dout("parse_ips got %s\n", ceph_pr_addr(ss));
1142
1143                 if (p == end)
1144                         break;
1145                 if (*p != ',')
1146                         goto bad;
1147                 p++;
1148         }
1149
1150         if (p != end)
1151                 goto bad;
1152
1153         if (count)
1154                 *count = i + 1;
1155         return 0;
1156
1157 bad:
1158         pr_err("parse_ips bad ip '%.*s'\n", (int)(end - c), c);
1159         return -EINVAL;
1160 }
1161 EXPORT_SYMBOL(ceph_parse_ips);
1162
1163 static int process_banner(struct ceph_connection *con)
1164 {
1165         dout("process_banner on %p\n", con);
1166
1167         if (verify_hello(con) < 0)
1168                 return -1;
1169
1170         ceph_decode_addr(&con->actual_peer_addr);
1171         ceph_decode_addr(&con->peer_addr_for_me);
1172
1173         /*
1174          * Make sure the other end is who we wanted.  note that the other
1175          * end may not yet know their ip address, so if it's 0.0.0.0, give
1176          * them the benefit of the doubt.
1177          */
1178         if (memcmp(&con->peer_addr, &con->actual_peer_addr,
1179                    sizeof(con->peer_addr)) != 0 &&
1180             !(addr_is_blank(&con->actual_peer_addr.in_addr) &&
1181               con->actual_peer_addr.nonce == con->peer_addr.nonce)) {
1182                 pr_warning("wrong peer, want %s/%d, got %s/%d\n",
1183                            ceph_pr_addr(&con->peer_addr.in_addr),
1184                            (int)le32_to_cpu(con->peer_addr.nonce),
1185                            ceph_pr_addr(&con->actual_peer_addr.in_addr),
1186                            (int)le32_to_cpu(con->actual_peer_addr.nonce));
1187                 con->error_msg = "wrong peer at address";
1188                 return -1;
1189         }
1190
1191         /*
1192          * did we learn our address?
1193          */
1194         if (addr_is_blank(&con->msgr->inst.addr.in_addr)) {
1195                 int port = addr_port(&con->msgr->inst.addr.in_addr);
1196
1197                 memcpy(&con->msgr->inst.addr.in_addr,
1198                        &con->peer_addr_for_me.in_addr,
1199                        sizeof(con->peer_addr_for_me.in_addr));
1200                 addr_set_port(&con->msgr->inst.addr.in_addr, port);
1201                 encode_my_addr(con->msgr);
1202                 dout("process_banner learned my addr is %s\n",
1203                      ceph_pr_addr(&con->msgr->inst.addr.in_addr));
1204         }
1205
1206         set_bit(NEGOTIATING, &con->state);
1207         prepare_read_connect(con);
1208         return 0;
1209 }
1210
1211 static void fail_protocol(struct ceph_connection *con)
1212 {
1213         reset_connection(con);
1214         set_bit(CLOSED, &con->state);  /* in case there's queued work */
1215
1216         mutex_unlock(&con->mutex);
1217         if (con->ops->bad_proto)
1218                 con->ops->bad_proto(con);
1219         mutex_lock(&con->mutex);
1220 }
1221
1222 static int process_connect(struct ceph_connection *con)
1223 {
1224         u64 sup_feat = con->msgr->supported_features;
1225         u64 req_feat = con->msgr->required_features;
1226         u64 server_feat = le64_to_cpu(con->in_reply.features);
1227         int ret;
1228
1229         dout("process_connect on %p tag %d\n", con, (int)con->in_tag);
1230
1231         switch (con->in_reply.tag) {
1232         case CEPH_MSGR_TAG_FEATURES:
1233                 pr_err("%s%lld %s feature set mismatch,"
1234                        " my %llx < server's %llx, missing %llx\n",
1235                        ENTITY_NAME(con->peer_name),
1236                        ceph_pr_addr(&con->peer_addr.in_addr),
1237                        sup_feat, server_feat, server_feat & ~sup_feat);
1238                 con->error_msg = "missing required protocol features";
1239                 fail_protocol(con);
1240                 return -1;
1241
1242         case CEPH_MSGR_TAG_BADPROTOVER:
1243                 pr_err("%s%lld %s protocol version mismatch,"
1244                        " my %d != server's %d\n",
1245                        ENTITY_NAME(con->peer_name),
1246                        ceph_pr_addr(&con->peer_addr.in_addr),
1247                        le32_to_cpu(con->out_connect.protocol_version),
1248                        le32_to_cpu(con->in_reply.protocol_version));
1249                 con->error_msg = "protocol version mismatch";
1250                 fail_protocol(con);
1251                 return -1;
1252
1253         case CEPH_MSGR_TAG_BADAUTHORIZER:
1254                 con->auth_retry++;
1255                 dout("process_connect %p got BADAUTHORIZER attempt %d\n", con,
1256                      con->auth_retry);
1257                 if (con->auth_retry == 2) {
1258                         con->error_msg = "connect authorization failure";
1259                         return -1;
1260                 }
1261                 con->auth_retry = 1;
1262                 ret = prepare_write_connect(con->msgr, con, 0);
1263                 if (ret < 0)
1264                         return ret;
1265                 prepare_read_connect(con);
1266                 break;
1267
1268         case CEPH_MSGR_TAG_RESETSESSION:
1269                 /*
1270                  * If we connected with a large connect_seq but the peer
1271                  * has no record of a session with us (no connection, or
1272                  * connect_seq == 0), they will send RESETSESION to indicate
1273                  * that they must have reset their session, and may have
1274                  * dropped messages.
1275                  */
1276                 dout("process_connect got RESET peer seq %u\n",
1277                      le32_to_cpu(con->in_connect.connect_seq));
1278                 pr_err("%s%lld %s connection reset\n",
1279                        ENTITY_NAME(con->peer_name),
1280                        ceph_pr_addr(&con->peer_addr.in_addr));
1281                 reset_connection(con);
1282                 prepare_write_connect(con->msgr, con, 0);
1283                 prepare_read_connect(con);
1284
1285                 /* Tell ceph about it. */
1286                 mutex_unlock(&con->mutex);
1287                 pr_info("reset on %s%lld\n", ENTITY_NAME(con->peer_name));
1288                 if (con->ops->peer_reset)
1289                         con->ops->peer_reset(con);
1290                 mutex_lock(&con->mutex);
1291                 if (test_bit(CLOSED, &con->state) ||
1292                     test_bit(OPENING, &con->state))
1293                         return -EAGAIN;
1294                 break;
1295
1296         case CEPH_MSGR_TAG_RETRY_SESSION:
1297                 /*
1298                  * If we sent a smaller connect_seq than the peer has, try
1299                  * again with a larger value.
1300                  */
1301                 dout("process_connect got RETRY my seq = %u, peer_seq = %u\n",
1302                      le32_to_cpu(con->out_connect.connect_seq),
1303                      le32_to_cpu(con->in_connect.connect_seq));
1304                 con->connect_seq = le32_to_cpu(con->in_connect.connect_seq);
1305                 prepare_write_connect(con->msgr, con, 0);
1306                 prepare_read_connect(con);
1307                 break;
1308
1309         case CEPH_MSGR_TAG_RETRY_GLOBAL:
1310                 /*
1311                  * If we sent a smaller global_seq than the peer has, try
1312                  * again with a larger value.
1313                  */
1314                 dout("process_connect got RETRY_GLOBAL my %u peer_gseq %u\n",
1315                      con->peer_global_seq,
1316                      le32_to_cpu(con->in_connect.global_seq));
1317                 get_global_seq(con->msgr,
1318                                le32_to_cpu(con->in_connect.global_seq));
1319                 prepare_write_connect(con->msgr, con, 0);
1320                 prepare_read_connect(con);
1321                 break;
1322
1323         case CEPH_MSGR_TAG_READY:
1324                 if (req_feat & ~server_feat) {
1325                         pr_err("%s%lld %s protocol feature mismatch,"
1326                                " my required %llx > server's %llx, need %llx\n",
1327                                ENTITY_NAME(con->peer_name),
1328                                ceph_pr_addr(&con->peer_addr.in_addr),
1329                                req_feat, server_feat, req_feat & ~server_feat);
1330                         con->error_msg = "missing required protocol features";
1331                         fail_protocol(con);
1332                         return -1;
1333                 }
1334                 clear_bit(CONNECTING, &con->state);
1335                 con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
1336                 con->connect_seq++;
1337                 con->peer_features = server_feat;
1338                 dout("process_connect got READY gseq %d cseq %d (%d)\n",
1339                      con->peer_global_seq,
1340                      le32_to_cpu(con->in_reply.connect_seq),
1341                      con->connect_seq);
1342                 WARN_ON(con->connect_seq !=
1343                         le32_to_cpu(con->in_reply.connect_seq));
1344
1345                 if (con->in_reply.flags & CEPH_MSG_CONNECT_LOSSY)
1346                         set_bit(LOSSYTX, &con->state);
1347
1348                 prepare_read_tag(con);
1349                 break;
1350
1351         case CEPH_MSGR_TAG_WAIT:
1352                 /*
1353                  * If there is a connection race (we are opening
1354                  * connections to each other), one of us may just have
1355                  * to WAIT.  This shouldn't happen if we are the
1356                  * client.
1357                  */
1358                 pr_err("process_connect got WAIT as client\n");
1359                 con->error_msg = "protocol error, got WAIT as client";
1360                 return -1;
1361
1362         default:
1363                 pr_err("connect protocol error, will retry\n");
1364                 con->error_msg = "protocol error, garbage tag during connect";
1365                 return -1;
1366         }
1367         return 0;
1368 }
1369
1370
1371 /*
1372  * read (part of) an ack
1373  */
1374 static int read_partial_ack(struct ceph_connection *con)
1375 {
1376         int to = 0;
1377
1378         return read_partial(con, &to, sizeof(con->in_temp_ack),
1379                             &con->in_temp_ack);
1380 }
1381
1382
1383 /*
1384  * We can finally discard anything that's been acked.
1385  */
1386 static void process_ack(struct ceph_connection *con)
1387 {
1388         struct ceph_msg *m;
1389         u64 ack = le64_to_cpu(con->in_temp_ack);
1390         u64 seq;
1391
1392         while (!list_empty(&con->out_sent)) {
1393                 m = list_first_entry(&con->out_sent, struct ceph_msg,
1394                                      list_head);
1395                 seq = le64_to_cpu(m->hdr.seq);
1396                 if (seq > ack)
1397                         break;
1398                 dout("got ack for seq %llu type %d at %p\n", seq,
1399                      le16_to_cpu(m->hdr.type), m);
1400                 ceph_msg_remove(m);
1401         }
1402         prepare_read_tag(con);
1403 }
1404
1405
1406
1407
1408 static int read_partial_message_section(struct ceph_connection *con,
1409                                         struct kvec *section,
1410                                         unsigned int sec_len, u32 *crc)
1411 {
1412         int ret, left;
1413
1414         BUG_ON(!section);
1415
1416         while (section->iov_len < sec_len) {
1417                 BUG_ON(section->iov_base == NULL);
1418                 left = sec_len - section->iov_len;
1419                 ret = ceph_tcp_recvmsg(con->sock, (char *)section->iov_base +
1420                                        section->iov_len, left);
1421                 if (ret <= 0)
1422                         return ret;
1423                 section->iov_len += ret;
1424                 if (section->iov_len == sec_len)
1425                         *crc = crc32c(0, section->iov_base,
1426                                       section->iov_len);
1427         }
1428
1429         return 1;
1430 }
1431
1432 static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
1433                                 struct ceph_msg_header *hdr,
1434                                 int *skip);
1435
1436
1437 static int read_partial_message_pages(struct ceph_connection *con,
1438                                       struct page **pages,
1439                                       unsigned data_len, int datacrc)
1440 {
1441         void *p;
1442         int ret;
1443         int left;
1444
1445         left = min((int)(data_len - con->in_msg_pos.data_pos),
1446                    (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
1447         /* (page) data */
1448         BUG_ON(pages == NULL);
1449         p = kmap(pages[con->in_msg_pos.page]);
1450         ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
1451                                left);
1452         if (ret > 0 && datacrc)
1453                 con->in_data_crc =
1454                         crc32c(con->in_data_crc,
1455                                   p + con->in_msg_pos.page_pos, ret);
1456         kunmap(pages[con->in_msg_pos.page]);
1457         if (ret <= 0)
1458                 return ret;
1459         con->in_msg_pos.data_pos += ret;
1460         con->in_msg_pos.page_pos += ret;
1461         if (con->in_msg_pos.page_pos == PAGE_SIZE) {
1462                 con->in_msg_pos.page_pos = 0;
1463                 con->in_msg_pos.page++;
1464         }
1465
1466         return ret;
1467 }
1468
1469 #ifdef CONFIG_BLOCK
1470 static int read_partial_message_bio(struct ceph_connection *con,
1471                                     struct bio **bio_iter, int *bio_seg,
1472                                     unsigned data_len, int datacrc)
1473 {
1474         struct bio_vec *bv = bio_iovec_idx(*bio_iter, *bio_seg);
1475         void *p;
1476         int ret, left;
1477
1478         if (IS_ERR(bv))
1479                 return PTR_ERR(bv);
1480
1481         left = min((int)(data_len - con->in_msg_pos.data_pos),
1482                    (int)(bv->bv_len - con->in_msg_pos.page_pos));
1483
1484         p = kmap(bv->bv_page) + bv->bv_offset;
1485
1486         ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
1487                                left);
1488         if (ret > 0 && datacrc)
1489                 con->in_data_crc =
1490                         crc32c(con->in_data_crc,
1491                                   p + con->in_msg_pos.page_pos, ret);
1492         kunmap(bv->bv_page);
1493         if (ret <= 0)
1494                 return ret;
1495         con->in_msg_pos.data_pos += ret;
1496         con->in_msg_pos.page_pos += ret;
1497         if (con->in_msg_pos.page_pos == bv->bv_len) {
1498                 con->in_msg_pos.page_pos = 0;
1499                 iter_bio_next(bio_iter, bio_seg);
1500         }
1501
1502         return ret;
1503 }
1504 #endif
1505
1506 /*
1507  * read (part of) a message.
1508  */
1509 static int read_partial_message(struct ceph_connection *con)
1510 {
1511         struct ceph_msg *m = con->in_msg;
1512         int ret;
1513         int to, left;
1514         unsigned front_len, middle_len, data_len;
1515         int datacrc = con->msgr->nocrc;
1516         int skip;
1517         u64 seq;
1518
1519         dout("read_partial_message con %p msg %p\n", con, m);
1520
1521         /* header */
1522         while (con->in_base_pos < sizeof(con->in_hdr)) {
1523                 left = sizeof(con->in_hdr) - con->in_base_pos;
1524                 ret = ceph_tcp_recvmsg(con->sock,
1525                                        (char *)&con->in_hdr + con->in_base_pos,
1526                                        left);
1527                 if (ret <= 0)
1528                         return ret;
1529                 con->in_base_pos += ret;
1530                 if (con->in_base_pos == sizeof(con->in_hdr)) {
1531                         u32 crc = crc32c(0, (void *)&con->in_hdr,
1532                                  sizeof(con->in_hdr) - sizeof(con->in_hdr.crc));
1533                         if (crc != le32_to_cpu(con->in_hdr.crc)) {
1534                                 pr_err("read_partial_message bad hdr "
1535                                        " crc %u != expected %u\n",
1536                                        crc, con->in_hdr.crc);
1537                                 return -EBADMSG;
1538                         }
1539                 }
1540         }
1541         front_len = le32_to_cpu(con->in_hdr.front_len);
1542         if (front_len > CEPH_MSG_MAX_FRONT_LEN)
1543                 return -EIO;
1544         middle_len = le32_to_cpu(con->in_hdr.middle_len);
1545         if (middle_len > CEPH_MSG_MAX_DATA_LEN)
1546                 return -EIO;
1547         data_len = le32_to_cpu(con->in_hdr.data_len);
1548         if (data_len > CEPH_MSG_MAX_DATA_LEN)
1549                 return -EIO;
1550
1551         /* verify seq# */
1552         seq = le64_to_cpu(con->in_hdr.seq);
1553         if ((s64)seq - (s64)con->in_seq < 1) {
1554                 pr_info("skipping %s%lld %s seq %lld expected %lld\n",
1555                         ENTITY_NAME(con->peer_name),
1556                         ceph_pr_addr(&con->peer_addr.in_addr),
1557                         seq, con->in_seq + 1);
1558                 con->in_base_pos = -front_len - middle_len - data_len -
1559                         sizeof(m->footer);
1560                 con->in_tag = CEPH_MSGR_TAG_READY;
1561                 return 0;
1562         } else if ((s64)seq - (s64)con->in_seq > 1) {
1563                 pr_err("read_partial_message bad seq %lld expected %lld\n",
1564                        seq, con->in_seq + 1);
1565                 con->error_msg = "bad message sequence # for incoming message";
1566                 return -EBADMSG;
1567         }
1568
1569         /* allocate message? */
1570         if (!con->in_msg) {
1571                 dout("got hdr type %d front %d data %d\n", con->in_hdr.type,
1572                      con->in_hdr.front_len, con->in_hdr.data_len);
1573                 skip = 0;
1574                 con->in_msg = ceph_alloc_msg(con, &con->in_hdr, &skip);
1575                 if (skip) {
1576                         /* skip this message */
1577                         dout("alloc_msg said skip message\n");
1578                         BUG_ON(con->in_msg);
1579                         con->in_base_pos = -front_len - middle_len - data_len -
1580                                 sizeof(m->footer);
1581                         con->in_tag = CEPH_MSGR_TAG_READY;
1582                         con->in_seq++;
1583                         return 0;
1584                 }
1585                 if (!con->in_msg) {
1586                         con->error_msg =
1587                                 "error allocating memory for incoming message";
1588                         return -ENOMEM;
1589                 }
1590                 m = con->in_msg;
1591                 m->front.iov_len = 0;    /* haven't read it yet */
1592                 if (m->middle)
1593                         m->middle->vec.iov_len = 0;
1594
1595                 con->in_msg_pos.page = 0;
1596                 if (m->pages)
1597                         con->in_msg_pos.page_pos = m->page_alignment;
1598                 else
1599                         con->in_msg_pos.page_pos = 0;
1600                 con->in_msg_pos.data_pos = 0;
1601         }
1602
1603         /* front */
1604         ret = read_partial_message_section(con, &m->front, front_len,
1605                                            &con->in_front_crc);
1606         if (ret <= 0)
1607                 return ret;
1608
1609         /* middle */
1610         if (m->middle) {
1611                 ret = read_partial_message_section(con, &m->middle->vec,
1612                                                    middle_len,
1613                                                    &con->in_middle_crc);
1614                 if (ret <= 0)
1615                         return ret;
1616         }
1617 #ifdef CONFIG_BLOCK
1618         if (m->bio && !m->bio_iter)
1619                 init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg);
1620 #endif
1621
1622         /* (page) data */
1623         while (con->in_msg_pos.data_pos < data_len) {
1624                 if (m->pages) {
1625                         ret = read_partial_message_pages(con, m->pages,
1626                                                  data_len, datacrc);
1627                         if (ret <= 0)
1628                                 return ret;
1629 #ifdef CONFIG_BLOCK
1630                 } else if (m->bio) {
1631
1632                         ret = read_partial_message_bio(con,
1633                                                  &m->bio_iter, &m->bio_seg,
1634                                                  data_len, datacrc);
1635                         if (ret <= 0)
1636                                 return ret;
1637 #endif
1638                 } else {
1639                         BUG_ON(1);
1640                 }
1641         }
1642
1643         /* footer */
1644         to = sizeof(m->hdr) + sizeof(m->footer);
1645         while (con->in_base_pos < to) {
1646                 left = to - con->in_base_pos;
1647                 ret = ceph_tcp_recvmsg(con->sock, (char *)&m->footer +
1648                                        (con->in_base_pos - sizeof(m->hdr)),
1649                                        left);
1650                 if (ret <= 0)
1651                         return ret;
1652                 con->in_base_pos += ret;
1653         }
1654         dout("read_partial_message got msg %p %d (%u) + %d (%u) + %d (%u)\n",
1655              m, front_len, m->footer.front_crc, middle_len,
1656              m->footer.middle_crc, data_len, m->footer.data_crc);
1657
1658         /* crc ok? */
1659         if (con->in_front_crc != le32_to_cpu(m->footer.front_crc)) {
1660                 pr_err("read_partial_message %p front crc %u != exp. %u\n",
1661                        m, con->in_front_crc, m->footer.front_crc);
1662                 return -EBADMSG;
1663         }
1664         if (con->in_middle_crc != le32_to_cpu(m->footer.middle_crc)) {
1665                 pr_err("read_partial_message %p middle crc %u != exp %u\n",
1666                        m, con->in_middle_crc, m->footer.middle_crc);
1667                 return -EBADMSG;
1668         }
1669         if (datacrc &&
1670             (m->footer.flags & CEPH_MSG_FOOTER_NOCRC) == 0 &&
1671             con->in_data_crc != le32_to_cpu(m->footer.data_crc)) {
1672                 pr_err("read_partial_message %p data crc %u != exp. %u\n", m,
1673                        con->in_data_crc, le32_to_cpu(m->footer.data_crc));
1674                 return -EBADMSG;
1675         }
1676
1677         return 1; /* done! */
1678 }
1679
1680 /*
1681  * Process message.  This happens in the worker thread.  The callback should
1682  * be careful not to do anything that waits on other incoming messages or it
1683  * may deadlock.
1684  */
1685 static void process_message(struct ceph_connection *con)
1686 {
1687         struct ceph_msg *msg;
1688
1689         msg = con->in_msg;
1690         con->in_msg = NULL;
1691
1692         /* if first message, set peer_name */
1693         if (con->peer_name.type == 0)
1694                 con->peer_name = msg->hdr.src;
1695
1696         con->in_seq++;
1697         mutex_unlock(&con->mutex);
1698
1699         dout("===== %p %llu from %s%lld %d=%s len %d+%d (%u %u %u) =====\n",
1700              msg, le64_to_cpu(msg->hdr.seq),
1701              ENTITY_NAME(msg->hdr.src),
1702              le16_to_cpu(msg->hdr.type),
1703              ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
1704              le32_to_cpu(msg->hdr.front_len),
1705              le32_to_cpu(msg->hdr.data_len),
1706              con->in_front_crc, con->in_middle_crc, con->in_data_crc);
1707         con->ops->dispatch(con, msg);
1708
1709         mutex_lock(&con->mutex);
1710         prepare_read_tag(con);
1711 }
1712
1713
1714 /*
1715  * Write something to the socket.  Called in a worker thread when the
1716  * socket appears to be writeable and we have something ready to send.
1717  */
1718 static int try_write(struct ceph_connection *con)
1719 {
1720         struct ceph_messenger *msgr = con->msgr;
1721         int ret = 1;
1722
1723         dout("try_write start %p state %lu nref %d\n", con, con->state,
1724              atomic_read(&con->nref));
1725
1726 more:
1727         dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes);
1728
1729         /* open the socket first? */
1730         if (con->sock == NULL) {
1731                 prepare_write_banner(msgr, con);
1732                 prepare_write_connect(msgr, con, 1);
1733                 prepare_read_banner(con);
1734                 set_bit(CONNECTING, &con->state);
1735                 clear_bit(NEGOTIATING, &con->state);
1736
1737                 BUG_ON(con->in_msg);
1738                 con->in_tag = CEPH_MSGR_TAG_READY;
1739                 dout("try_write initiating connect on %p new state %lu\n",
1740                      con, con->state);
1741                 con->sock = ceph_tcp_connect(con);
1742                 if (IS_ERR(con->sock)) {
1743                         con->sock = NULL;
1744                         con->error_msg = "connect error";
1745                         ret = -1;
1746                         goto out;
1747                 }
1748         }
1749
1750 more_kvec:
1751         /* kvec data queued? */
1752         if (con->out_skip) {
1753                 ret = write_partial_skip(con);
1754                 if (ret <= 0)
1755                         goto out;
1756         }
1757         if (con->out_kvec_left) {
1758                 ret = write_partial_kvec(con);
1759                 if (ret <= 0)
1760                         goto out;
1761         }
1762
1763         /* msg pages? */
1764         if (con->out_msg) {
1765                 if (con->out_msg_done) {
1766                         ceph_msg_put(con->out_msg);
1767                         con->out_msg = NULL;   /* we're done with this one */
1768                         goto do_next;
1769                 }
1770
1771                 ret = write_partial_msg_pages(con);
1772                 if (ret == 1)
1773                         goto more_kvec;  /* we need to send the footer, too! */
1774                 if (ret == 0)
1775                         goto out;
1776                 if (ret < 0) {
1777                         dout("try_write write_partial_msg_pages err %d\n",
1778                              ret);
1779                         goto out;
1780                 }
1781         }
1782
1783 do_next:
1784         if (!test_bit(CONNECTING, &con->state)) {
1785                 /* is anything else pending? */
1786                 if (!list_empty(&con->out_queue)) {
1787                         prepare_write_message(con);
1788                         goto more;
1789                 }
1790                 if (con->in_seq > con->in_seq_acked) {
1791                         prepare_write_ack(con);
1792                         goto more;
1793                 }
1794                 if (test_and_clear_bit(KEEPALIVE_PENDING, &con->state)) {
1795                         prepare_write_keepalive(con);
1796                         goto more;
1797                 }
1798         }
1799
1800         /* Nothing to do! */
1801         clear_bit(WRITE_PENDING, &con->state);
1802         dout("try_write nothing else to write.\n");
1803         ret = 0;
1804 out:
1805         dout("try_write done on %p ret %d\n", con, ret);
1806         return ret;
1807 }
1808
1809
1810
1811 /*
1812  * Read what we can from the socket.
1813  */
1814 static int try_read(struct ceph_connection *con)
1815 {
1816         int ret = -1;
1817
1818         if (!con->sock)
1819                 return 0;
1820
1821         if (test_bit(STANDBY, &con->state))
1822                 return 0;
1823
1824         dout("try_read start on %p\n", con);
1825
1826 more:
1827         dout("try_read tag %d in_base_pos %d\n", (int)con->in_tag,
1828              con->in_base_pos);
1829
1830         /*
1831          * process_connect and process_message drop and re-take
1832          * con->mutex.  make sure we handle a racing close or reopen.
1833          */
1834         if (test_bit(CLOSED, &con->state) ||
1835             test_bit(OPENING, &con->state)) {
1836                 ret = -EAGAIN;
1837                 goto out;
1838         }
1839
1840         if (test_bit(CONNECTING, &con->state)) {
1841                 if (!test_bit(NEGOTIATING, &con->state)) {
1842                         dout("try_read connecting\n");
1843                         ret = read_partial_banner(con);
1844                         if (ret <= 0)
1845                                 goto out;
1846                         ret = process_banner(con);
1847                         if (ret < 0)
1848                                 goto out;
1849                 }
1850                 ret = read_partial_connect(con);
1851                 if (ret <= 0)
1852                         goto out;
1853                 ret = process_connect(con);
1854                 if (ret < 0)
1855                         goto out;
1856                 goto more;
1857         }
1858
1859         if (con->in_base_pos < 0) {
1860                 /*
1861                  * skipping + discarding content.
1862                  *
1863                  * FIXME: there must be a better way to do this!
1864                  */
1865                 static char buf[1024];
1866                 int skip = min(1024, -con->in_base_pos);
1867                 dout("skipping %d / %d bytes\n", skip, -con->in_base_pos);
1868                 ret = ceph_tcp_recvmsg(con->sock, buf, skip);
1869                 if (ret <= 0)
1870                         goto out;
1871                 con->in_base_pos += ret;
1872                 if (con->in_base_pos)
1873                         goto more;
1874         }
1875         if (con->in_tag == CEPH_MSGR_TAG_READY) {
1876                 /*
1877                  * what's next?
1878                  */
1879                 ret = ceph_tcp_recvmsg(con->sock, &con->in_tag, 1);
1880                 if (ret <= 0)
1881                         goto out;
1882                 dout("try_read got tag %d\n", (int)con->in_tag);
1883                 switch (con->in_tag) {
1884                 case CEPH_MSGR_TAG_MSG:
1885                         prepare_read_message(con);
1886                         break;
1887                 case CEPH_MSGR_TAG_ACK:
1888                         prepare_read_ack(con);
1889                         break;
1890                 case CEPH_MSGR_TAG_CLOSE:
1891                         set_bit(CLOSED, &con->state);   /* fixme */
1892                         goto out;
1893                 default:
1894                         goto bad_tag;
1895                 }
1896         }
1897         if (con->in_tag == CEPH_MSGR_TAG_MSG) {
1898                 ret = read_partial_message(con);
1899                 if (ret <= 0) {
1900                         switch (ret) {
1901                         case -EBADMSG:
1902                                 con->error_msg = "bad crc";
1903                                 ret = -EIO;
1904                                 break;
1905                         case -EIO:
1906                                 con->error_msg = "io error";
1907                                 break;
1908                         }
1909                         goto out;
1910                 }
1911                 if (con->in_tag == CEPH_MSGR_TAG_READY)
1912                         goto more;
1913                 process_message(con);
1914                 goto more;
1915         }
1916         if (con->in_tag == CEPH_MSGR_TAG_ACK) {
1917                 ret = read_partial_ack(con);
1918                 if (ret <= 0)
1919                         goto out;
1920                 process_ack(con);
1921                 goto more;
1922         }
1923
1924 out:
1925         dout("try_read done on %p ret %d\n", con, ret);
1926         return ret;
1927
1928 bad_tag:
1929         pr_err("try_read bad con->in_tag = %d\n", (int)con->in_tag);
1930         con->error_msg = "protocol error, garbage tag";
1931         ret = -1;
1932         goto out;
1933 }
1934
1935
1936 /*
1937  * Atomically queue work on a connection.  Bump @con reference to
1938  * avoid races with connection teardown.
1939  */
1940 static void queue_con(struct ceph_connection *con)
1941 {
1942         if (test_bit(DEAD, &con->state)) {
1943                 dout("queue_con %p ignoring: DEAD\n",
1944                      con);
1945                 return;
1946         }
1947
1948         if (!con->ops->get(con)) {
1949                 dout("queue_con %p ref count 0\n", con);
1950                 return;
1951         }
1952
1953         if (!queue_delayed_work(ceph_msgr_wq, &con->work, 0)) {
1954                 dout("queue_con %p - already queued\n", con);
1955                 con->ops->put(con);
1956         } else {
1957                 dout("queue_con %p\n", con);
1958         }
1959 }
1960
1961 /*
1962  * Do some work on a connection.  Drop a connection ref when we're done.
1963  */
1964 static void con_work(struct work_struct *work)
1965 {
1966         struct ceph_connection *con = container_of(work, struct ceph_connection,
1967                                                    work.work);
1968         int ret;
1969
1970         mutex_lock(&con->mutex);
1971 restart:
1972         if (test_and_clear_bit(BACKOFF, &con->state)) {
1973                 dout("con_work %p backing off\n", con);
1974                 if (queue_delayed_work(ceph_msgr_wq, &con->work,
1975                                        round_jiffies_relative(con->delay))) {
1976                         dout("con_work %p backoff %lu\n", con, con->delay);
1977                         mutex_unlock(&con->mutex);
1978                         return;
1979                 } else {
1980                         con->ops->put(con);
1981                         dout("con_work %p FAILED to back off %lu\n", con,
1982                              con->delay);
1983                 }
1984         }
1985
1986         if (test_bit(STANDBY, &con->state)) {
1987                 dout("con_work %p STANDBY\n", con);
1988                 goto done;
1989         }
1990         if (test_bit(CLOSED, &con->state)) { /* e.g. if we are replaced */
1991                 dout("con_work CLOSED\n");
1992                 con_close_socket(con);
1993                 goto done;
1994         }
1995         if (test_and_clear_bit(OPENING, &con->state)) {
1996                 /* reopen w/ new peer */
1997                 dout("con_work OPENING\n");
1998                 con_close_socket(con);
1999         }
2000
2001         if (test_and_clear_bit(SOCK_CLOSED, &con->state))
2002                 goto fault;
2003
2004         ret = try_read(con);
2005         if (ret == -EAGAIN)
2006                 goto restart;
2007         if (ret < 0)
2008                 goto fault;
2009
2010         ret = try_write(con);
2011         if (ret == -EAGAIN)
2012                 goto restart;
2013         if (ret < 0)
2014                 goto fault;
2015
2016 done:
2017         mutex_unlock(&con->mutex);
2018 done_unlocked:
2019         con->ops->put(con);
2020         return;
2021
2022 fault:
2023         mutex_unlock(&con->mutex);
2024         ceph_fault(con);     /* error/fault path */
2025         goto done_unlocked;
2026 }
2027
2028
2029 /*
2030  * Generic error/fault handler.  A retry mechanism is used with
2031  * exponential backoff
2032  */
2033 static void ceph_fault(struct ceph_connection *con)
2034 {
2035         pr_err("%s%lld %s %s\n", ENTITY_NAME(con->peer_name),
2036                ceph_pr_addr(&con->peer_addr.in_addr), con->error_msg);
2037         dout("fault %p state %lu to peer %s\n",
2038              con, con->state, ceph_pr_addr(&con->peer_addr.in_addr));
2039
2040         if (test_bit(LOSSYTX, &con->state)) {
2041                 dout("fault on LOSSYTX channel\n");
2042                 goto out;
2043         }
2044
2045         mutex_lock(&con->mutex);
2046         if (test_bit(CLOSED, &con->state))
2047                 goto out_unlock;
2048
2049         con_close_socket(con);
2050
2051         if (con->in_msg) {
2052                 ceph_msg_put(con->in_msg);
2053                 con->in_msg = NULL;
2054         }
2055
2056         /* Requeue anything that hasn't been acked */
2057         list_splice_init(&con->out_sent, &con->out_queue);
2058
2059         /* If there are no messages queued or keepalive pending, place
2060          * the connection in a STANDBY state */
2061         if (list_empty(&con->out_queue) &&
2062             !test_bit(KEEPALIVE_PENDING, &con->state)) {
2063                 dout("fault %p setting STANDBY clearing WRITE_PENDING\n", con);
2064                 clear_bit(WRITE_PENDING, &con->state);
2065                 set_bit(STANDBY, &con->state);
2066         } else {
2067                 /* retry after a delay. */
2068                 if (con->delay == 0)
2069                         con->delay = BASE_DELAY_INTERVAL;
2070                 else if (con->delay < MAX_DELAY_INTERVAL)
2071                         con->delay *= 2;
2072                 con->ops->get(con);
2073                 if (queue_delayed_work(ceph_msgr_wq, &con->work,
2074                                        round_jiffies_relative(con->delay))) {
2075                         dout("fault queued %p delay %lu\n", con, con->delay);
2076                 } else {
2077                         con->ops->put(con);
2078                         dout("fault failed to queue %p delay %lu, backoff\n",
2079                              con, con->delay);
2080                         /*
2081                          * In many cases we see a socket state change
2082                          * while con_work is running and end up
2083                          * queuing (non-delayed) work, such that we
2084                          * can't backoff with a delay.  Set a flag so
2085                          * that when con_work restarts we schedule the
2086                          * delay then.
2087                          */
2088                         set_bit(BACKOFF, &con->state);
2089                 }
2090         }
2091
2092 out_unlock:
2093         mutex_unlock(&con->mutex);
2094 out:
2095         /*
2096          * in case we faulted due to authentication, invalidate our
2097          * current tickets so that we can get new ones.
2098          */
2099         if (con->auth_retry && con->ops->invalidate_authorizer) {
2100                 dout("calling invalidate_authorizer()\n");
2101                 con->ops->invalidate_authorizer(con);
2102         }
2103
2104         if (con->ops->fault)
2105                 con->ops->fault(con);
2106 }
2107
2108
2109
2110 /*
2111  * create a new messenger instance
2112  */
2113 struct ceph_messenger *ceph_messenger_create(struct ceph_entity_addr *myaddr,
2114                                              u32 supported_features,
2115                                              u32 required_features)
2116 {
2117         struct ceph_messenger *msgr;
2118
2119         msgr = kzalloc(sizeof(*msgr), GFP_KERNEL);
2120         if (msgr == NULL)
2121                 return ERR_PTR(-ENOMEM);
2122
2123         msgr->supported_features = supported_features;
2124         msgr->required_features = required_features;
2125
2126         spin_lock_init(&msgr->global_seq_lock);
2127
2128         /* the zero page is needed if a request is "canceled" while the message
2129          * is being written over the socket */
2130         msgr->zero_page = __page_cache_alloc(GFP_KERNEL | __GFP_ZERO);
2131         if (!msgr->zero_page) {
2132                 kfree(msgr);
2133                 return ERR_PTR(-ENOMEM);
2134         }
2135         kmap(msgr->zero_page);
2136
2137         if (myaddr)
2138                 msgr->inst.addr = *myaddr;
2139
2140         /* select a random nonce */
2141         msgr->inst.addr.type = 0;
2142         get_random_bytes(&msgr->inst.addr.nonce, sizeof(msgr->inst.addr.nonce));
2143         encode_my_addr(msgr);
2144
2145         dout("messenger_create %p\n", msgr);
2146         return msgr;
2147 }
2148 EXPORT_SYMBOL(ceph_messenger_create);
2149
2150 void ceph_messenger_destroy(struct ceph_messenger *msgr)
2151 {
2152         dout("destroy %p\n", msgr);
2153         kunmap(msgr->zero_page);
2154         __free_page(msgr->zero_page);
2155         kfree(msgr);
2156         dout("destroyed messenger %p\n", msgr);
2157 }
2158 EXPORT_SYMBOL(ceph_messenger_destroy);
2159
2160 static void clear_standby(struct ceph_connection *con)
2161 {
2162         /* come back from STANDBY? */
2163         if (test_and_clear_bit(STANDBY, &con->state)) {
2164                 mutex_lock(&con->mutex);
2165                 dout("clear_standby %p and ++connect_seq\n", con);
2166                 con->connect_seq++;
2167                 WARN_ON(test_bit(WRITE_PENDING, &con->state));
2168                 WARN_ON(test_bit(KEEPALIVE_PENDING, &con->state));
2169                 mutex_unlock(&con->mutex);
2170         }
2171 }
2172
2173 /*
2174  * Queue up an outgoing message on the given connection.
2175  */
2176 void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg)
2177 {
2178         if (test_bit(CLOSED, &con->state)) {
2179                 dout("con_send %p closed, dropping %p\n", con, msg);
2180                 ceph_msg_put(msg);
2181                 return;
2182         }
2183
2184         /* set src+dst */
2185         msg->hdr.src = con->msgr->inst.name;
2186
2187         BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len));
2188
2189         msg->needs_out_seq = true;
2190
2191         /* queue */
2192         mutex_lock(&con->mutex);
2193         BUG_ON(!list_empty(&msg->list_head));
2194         list_add_tail(&msg->list_head, &con->out_queue);
2195         dout("----- %p to %s%lld %d=%s len %d+%d+%d -----\n", msg,
2196              ENTITY_NAME(con->peer_name), le16_to_cpu(msg->hdr.type),
2197              ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
2198              le32_to_cpu(msg->hdr.front_len),
2199              le32_to_cpu(msg->hdr.middle_len),
2200              le32_to_cpu(msg->hdr.data_len));
2201         mutex_unlock(&con->mutex);
2202
2203         /* if there wasn't anything waiting to send before, queue
2204          * new work */
2205         clear_standby(con);
2206         if (test_and_set_bit(WRITE_PENDING, &con->state) == 0)
2207                 queue_con(con);
2208 }
2209 EXPORT_SYMBOL(ceph_con_send);
2210
2211 /*
2212  * Revoke a message that was previously queued for send
2213  */
2214 void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg)
2215 {
2216         mutex_lock(&con->mutex);
2217         if (!list_empty(&msg->list_head)) {
2218                 dout("con_revoke %p msg %p - was on queue\n", con, msg);
2219                 list_del_init(&msg->list_head);
2220                 ceph_msg_put(msg);
2221                 msg->hdr.seq = 0;
2222         }
2223         if (con->out_msg == msg) {
2224                 dout("con_revoke %p msg %p - was sending\n", con, msg);
2225                 con->out_msg = NULL;
2226                 if (con->out_kvec_is_msg) {
2227                         con->out_skip = con->out_kvec_bytes;
2228                         con->out_kvec_is_msg = false;
2229                 }
2230                 ceph_msg_put(msg);
2231                 msg->hdr.seq = 0;
2232         }
2233         mutex_unlock(&con->mutex);
2234 }
2235
2236 /*
2237  * Revoke a message that we may be reading data into
2238  */
2239 void ceph_con_revoke_message(struct ceph_connection *con, struct ceph_msg *msg)
2240 {
2241         mutex_lock(&con->mutex);
2242         if (con->in_msg && con->in_msg == msg) {
2243                 unsigned front_len = le32_to_cpu(con->in_hdr.front_len);
2244                 unsigned middle_len = le32_to_cpu(con->in_hdr.middle_len);
2245                 unsigned data_len = le32_to_cpu(con->in_hdr.data_len);
2246
2247                 /* skip rest of message */
2248                 dout("con_revoke_pages %p msg %p revoked\n", con, msg);
2249                         con->in_base_pos = con->in_base_pos -
2250                                 sizeof(struct ceph_msg_header) -
2251                                 front_len -
2252                                 middle_len -
2253                                 data_len -
2254                                 sizeof(struct ceph_msg_footer);
2255                 ceph_msg_put(con->in_msg);
2256                 con->in_msg = NULL;
2257                 con->in_tag = CEPH_MSGR_TAG_READY;
2258                 con->in_seq++;
2259         } else {
2260                 dout("con_revoke_pages %p msg %p pages %p no-op\n",
2261                      con, con->in_msg, msg);
2262         }
2263         mutex_unlock(&con->mutex);
2264 }
2265
2266 /*
2267  * Queue a keepalive byte to ensure the tcp connection is alive.
2268  */
2269 void ceph_con_keepalive(struct ceph_connection *con)
2270 {
2271         dout("con_keepalive %p\n", con);
2272         clear_standby(con);
2273         if (test_and_set_bit(KEEPALIVE_PENDING, &con->state) == 0 &&
2274             test_and_set_bit(WRITE_PENDING, &con->state) == 0)
2275                 queue_con(con);
2276 }
2277 EXPORT_SYMBOL(ceph_con_keepalive);
2278
2279
2280 /*
2281  * construct a new message with given type, size
2282  * the new msg has a ref count of 1.
2283  */
2284 struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags)
2285 {
2286         struct ceph_msg *m;
2287
2288         m = kmalloc(sizeof(*m), flags);
2289         if (m == NULL)
2290                 goto out;
2291         kref_init(&m->kref);
2292         INIT_LIST_HEAD(&m->list_head);
2293
2294         m->hdr.tid = 0;
2295         m->hdr.type = cpu_to_le16(type);
2296         m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT);
2297         m->hdr.version = 0;
2298         m->hdr.front_len = cpu_to_le32(front_len);
2299         m->hdr.middle_len = 0;
2300         m->hdr.data_len = 0;
2301         m->hdr.data_off = 0;
2302         m->hdr.reserved = 0;
2303         m->footer.front_crc = 0;
2304         m->footer.middle_crc = 0;
2305         m->footer.data_crc = 0;
2306         m->footer.flags = 0;
2307         m->front_max = front_len;
2308         m->front_is_vmalloc = false;
2309         m->more_to_follow = false;
2310         m->pool = NULL;
2311
2312         /* middle */
2313         m->middle = NULL;
2314
2315         /* data */
2316         m->nr_pages = 0;
2317         m->page_alignment = 0;
2318         m->pages = NULL;
2319         m->pagelist = NULL;
2320         m->bio = NULL;
2321         m->bio_iter = NULL;
2322         m->bio_seg = 0;
2323         m->trail = NULL;
2324
2325         /* front */
2326         if (front_len) {
2327                 if (front_len > PAGE_CACHE_SIZE) {
2328                         m->front.iov_base = __vmalloc(front_len, flags,
2329                                                       PAGE_KERNEL);
2330                         m->front_is_vmalloc = true;
2331                 } else {
2332                         m->front.iov_base = kmalloc(front_len, flags);
2333                 }
2334                 if (m->front.iov_base == NULL) {
2335                         pr_err("msg_new can't allocate %d bytes\n",
2336                              front_len);
2337                         goto out2;
2338                 }
2339         } else {
2340                 m->front.iov_base = NULL;
2341         }
2342         m->front.iov_len = front_len;
2343
2344         dout("ceph_msg_new %p front %d\n", m, front_len);
2345         return m;
2346
2347 out2:
2348         ceph_msg_put(m);
2349 out:
2350         pr_err("msg_new can't create type %d front %d\n", type, front_len);
2351         return NULL;
2352 }
2353 EXPORT_SYMBOL(ceph_msg_new);
2354
2355 /*
2356  * Allocate "middle" portion of a message, if it is needed and wasn't
2357  * allocated by alloc_msg.  This allows us to read a small fixed-size
2358  * per-type header in the front and then gracefully fail (i.e.,
2359  * propagate the error to the caller based on info in the front) when
2360  * the middle is too large.
2361  */
2362 static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg)
2363 {
2364         int type = le16_to_cpu(msg->hdr.type);
2365         int middle_len = le32_to_cpu(msg->hdr.middle_len);
2366
2367         dout("alloc_middle %p type %d %s middle_len %d\n", msg, type,
2368              ceph_msg_type_name(type), middle_len);
2369         BUG_ON(!middle_len);
2370         BUG_ON(msg->middle);
2371
2372         msg->middle = ceph_buffer_new(middle_len, GFP_NOFS);
2373         if (!msg->middle)
2374                 return -ENOMEM;
2375         return 0;
2376 }
2377
2378 /*
2379  * Generic message allocator, for incoming messages.
2380  */
2381 static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
2382                                 struct ceph_msg_header *hdr,
2383                                 int *skip)
2384 {
2385         int type = le16_to_cpu(hdr->type);
2386         int front_len = le32_to_cpu(hdr->front_len);
2387         int middle_len = le32_to_cpu(hdr->middle_len);
2388         struct ceph_msg *msg = NULL;
2389         int ret;
2390
2391         if (con->ops->alloc_msg) {
2392                 mutex_unlock(&con->mutex);
2393                 msg = con->ops->alloc_msg(con, hdr, skip);
2394                 mutex_lock(&con->mutex);
2395                 if (!msg || *skip)
2396                         return NULL;
2397         }
2398         if (!msg) {
2399                 *skip = 0;
2400                 msg = ceph_msg_new(type, front_len, GFP_NOFS);
2401                 if (!msg) {
2402                         pr_err("unable to allocate msg type %d len %d\n",
2403                                type, front_len);
2404                         return NULL;
2405                 }
2406                 msg->page_alignment = le16_to_cpu(hdr->data_off);
2407         }
2408         memcpy(&msg->hdr, &con->in_hdr, sizeof(con->in_hdr));
2409
2410         if (middle_len && !msg->middle) {
2411                 ret = ceph_alloc_middle(con, msg);
2412                 if (ret < 0) {
2413                         ceph_msg_put(msg);
2414                         return NULL;
2415                 }
2416         }
2417
2418         return msg;
2419 }
2420
2421
2422 /*
2423  * Free a generically kmalloc'd message.
2424  */
2425 void ceph_msg_kfree(struct ceph_msg *m)
2426 {
2427         dout("msg_kfree %p\n", m);
2428         if (m->front_is_vmalloc)
2429                 vfree(m->front.iov_base);
2430         else
2431                 kfree(m->front.iov_base);
2432         kfree(m);
2433 }
2434
2435 /*
2436  * Drop a msg ref.  Destroy as needed.
2437  */
2438 void ceph_msg_last_put(struct kref *kref)
2439 {
2440         struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
2441
2442         dout("ceph_msg_put last one on %p\n", m);
2443         WARN_ON(!list_empty(&m->list_head));
2444
2445         /* drop middle, data, if any */
2446         if (m->middle) {
2447                 ceph_buffer_put(m->middle);
2448                 m->middle = NULL;
2449         }
2450         m->nr_pages = 0;
2451         m->pages = NULL;
2452
2453         if (m->pagelist) {
2454                 ceph_pagelist_release(m->pagelist);
2455                 kfree(m->pagelist);
2456                 m->pagelist = NULL;
2457         }
2458
2459         m->trail = NULL;
2460
2461         if (m->pool)
2462                 ceph_msgpool_put(m->pool, m);
2463         else
2464                 ceph_msg_kfree(m);
2465 }
2466 EXPORT_SYMBOL(ceph_msg_last_put);
2467
2468 void ceph_msg_dump(struct ceph_msg *msg)
2469 {
2470         pr_debug("msg_dump %p (front_max %d nr_pages %d)\n", msg,
2471                  msg->front_max, msg->nr_pages);
2472         print_hex_dump(KERN_DEBUG, "header: ",
2473                        DUMP_PREFIX_OFFSET, 16, 1,
2474                        &msg->hdr, sizeof(msg->hdr), true);
2475         print_hex_dump(KERN_DEBUG, " front: ",
2476                        DUMP_PREFIX_OFFSET, 16, 1,
2477                        msg->front.iov_base, msg->front.iov_len, true);
2478         if (msg->middle)
2479                 print_hex_dump(KERN_DEBUG, "middle: ",
2480                                DUMP_PREFIX_OFFSET, 16, 1,
2481                                msg->middle->vec.iov_base,
2482                                msg->middle->vec.iov_len, true);
2483         print_hex_dump(KERN_DEBUG, "footer: ",
2484                        DUMP_PREFIX_OFFSET, 16, 1,
2485                        &msg->footer, sizeof(msg->footer), true);
2486 }
2487 EXPORT_SYMBOL(ceph_msg_dump);