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