fs/ceph/messenger.c

   1 #include "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 <net/tcp.h>
  13
  14 #include "super.h"
  15 #include "messenger.h"
  16 #include "decode.h"
  17 #include "pagelist.h"
  18
  19 /*
  20  * Ceph uses the messenger to exchange ceph_msg messages with other
  21  * hosts in the system.  The messenger provides ordered and reliable
  22  * delivery.  We tolerate TCP disconnects by reconnecting (with
  23  * exponential backoff) in the case of a fault (disconnection, bad
  24  * crc, protocol error).  Acks allow sent messages to be discarded by
  25  * the sender.
  26  */
  27
  28 /* static tag bytes (protocol control messages) */
  29 static char tag_msg = CEPH_MSGR_TAG_MSG;
  30 static char tag_ack = CEPH_MSGR_TAG_ACK;
  31 static char tag_keepalive = CEPH_MSGR_TAG_KEEPALIVE;
  32
  33
  34 static void queue_con(struct ceph_connection *con);
  35 static void con_work(struct work_struct *);
  36 static void ceph_fault(struct ceph_connection *con);
  37
  38 const char *ceph_name_type_str(int t)
  39 {
  40         switch (t) {
  41         case CEPH_ENTITY_TYPE_MON: return "mon";
  42         case CEPH_ENTITY_TYPE_MDS: return "mds";
  43         case CEPH_ENTITY_TYPE_OSD: return "osd";
  44         case CEPH_ENTITY_TYPE_CLIENT: return "client";
  45         case CEPH_ENTITY_TYPE_ADMIN: return "admin";
  46         default: return "???";
  47         }
  48 }
  49
  50 /*
  51  * nicely render a sockaddr as a string.
  52  */
  53 #define MAX_ADDR_STR 20
  54 static char addr_str[MAX_ADDR_STR][40];
  55 static DEFINE_SPINLOCK(addr_str_lock);
  56 static int last_addr_str;
  57
  58 const char *pr_addr(const struct sockaddr_storage *ss)
  59 {
  60         int i;
  61         char *s;
  62         struct sockaddr_in *in4 = (void *)ss;
  63         unsigned char *quad = (void *)&in4->sin_addr.s_addr;
  64         struct sockaddr_in6 *in6 = (void *)ss;
  65
  66         spin_lock(&addr_str_lock);
  67         i = last_addr_str++;
  68         if (last_addr_str == MAX_ADDR_STR)
  69                 last_addr_str = 0;
  70         spin_unlock(&addr_str_lock);
  71         s = addr_str[i];
  72
  73         switch (ss->ss_family) {
  74         case AF_INET:
  75                 sprintf(s, "%u.%u.%u.%u:%u",
  76                         (unsigned int)quad[0],
  77                         (unsigned int)quad[1],
  78                         (unsigned int)quad[2],
  79                         (unsigned int)quad[3],
  80                         (unsigned int)ntohs(in4->sin_port));
  81                 break;
  82
  83         case AF_INET6:
  84                 sprintf(s, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%u",
  85                         in6->sin6_addr.s6_addr16[0],
  86                         in6->sin6_addr.s6_addr16[1],
  87                         in6->sin6_addr.s6_addr16[2],
  88                         in6->sin6_addr.s6_addr16[3],
  89                         in6->sin6_addr.s6_addr16[4],
  90                         in6->sin6_addr.s6_addr16[5],
  91                         in6->sin6_addr.s6_addr16[6],
  92                         in6->sin6_addr.s6_addr16[7],
  93                         (unsigned int)ntohs(in6->sin6_port));
  94                 break;
  95
  96         default:
  97                 sprintf(s, "(unknown sockaddr family %d)", (int)ss->ss_family);
  98         }
  99
 100         return s;
 101 }
 102
 103 static void encode_my_addr(struct ceph_messenger *msgr)
 104 {
 105         memcpy(&msgr->my_enc_addr, &msgr->inst.addr, sizeof(msgr->my_enc_addr));
 106         ceph_encode_addr(&msgr->my_enc_addr);
 107 }
 108
 109 /*
 110  * work queue for all reading and writing to/from the socket.
 111  */
 112 struct workqueue_struct *ceph_msgr_wq;
 113
 114 int __init ceph_msgr_init(void)
 115 {
 116         ceph_msgr_wq = create_workqueue("ceph-msgr");
 117         if (IS_ERR(ceph_msgr_wq)) {
 118                 int ret = PTR_ERR(ceph_msgr_wq);
 119                 pr_err("msgr_init failed to create workqueue: %d\n", ret);
 120                 ceph_msgr_wq = NULL;
 121                 return ret;
 122         }
 123         return 0;
 124 }
 125
 126 void ceph_msgr_exit(void)
 127 {
 128         destroy_workqueue(ceph_msgr_wq);
 129 }
 130
 131 /*
 132  * socket callback functions
 133  */
 134
 135 /* data available on socket, or listen socket received a connect */
 136 static void ceph_data_ready(struct sock *sk, int count_unused)
 137 {
 138         struct ceph_connection *con =
 139                 (struct ceph_connection *)sk->sk_user_data;
 140         if (sk->sk_state != TCP_CLOSE_WAIT) {
 141                 dout("ceph_data_ready on %p state = %lu, queueing work\n",
 142                      con, con->state);
 143                 queue_con(con);
 144         }
 145 }
 146
 147 /* socket has buffer space for writing */
 148 static void ceph_write_space(struct sock *sk)
 149 {
 150         struct ceph_connection *con =
 151                 (struct ceph_connection *)sk->sk_user_data;
 152
 153         /* only queue to workqueue if there is data we want to write. */
 154         if (test_bit(WRITE_PENDING, &con->state)) {
 155                 dout("ceph_write_space %p queueing write work\n", con);
 156                 queue_con(con);
 157         } else {
 158                 dout("ceph_write_space %p nothing to write\n", con);
 159         }
 160
 161         /* since we have our own write_space, clear the SOCK_NOSPACE flag */
 162         clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 163 }
 164
 165 /* socket's state has changed */
 166 static void ceph_state_change(struct sock *sk)
 167 {
 168         struct ceph_connection *con =
 169                 (struct ceph_connection *)sk->sk_user_data;
 170
 171         dout("ceph_state_change %p state = %lu sk_state = %u\n",
 172              con, con->state, sk->sk_state);
 173
 174         if (test_bit(CLOSED, &con->state))
 175                 return;
 176
 177         switch (sk->sk_state) {
 178         case TCP_CLOSE:
 179                 dout("ceph_state_change TCP_CLOSE\n");
 180         case TCP_CLOSE_WAIT:
 181                 dout("ceph_state_change TCP_CLOSE_WAIT\n");
 182                 if (test_and_set_bit(SOCK_CLOSED, &con->state) == 0) {
 183                         if (test_bit(CONNECTING, &con->state))
 184                                 con->error_msg = "connection failed";
 185                         else
 186                                 con->error_msg = "socket closed";
 187                         queue_con(con);
 188                 }
 189                 break;
 190         case TCP_ESTABLISHED:
 191                 dout("ceph_state_change TCP_ESTABLISHED\n");
 192                 queue_con(con);
 193                 break;
 194         }
 195 }
 196
 197 /*
 198  * set up socket callbacks
 199  */
 200 static void set_sock_callbacks(struct socket *sock,
 201                                struct ceph_connection *con)
 202 {
 203         struct sock *sk = sock->sk;
 204         sk->sk_user_data = (void *)con;
 205         sk->sk_data_ready = ceph_data_ready;
 206         sk->sk_write_space = ceph_write_space;
 207         sk->sk_state_change = ceph_state_change;
 208 }
 209
 210
 211 /*
 212  * socket helpers
 213  */
 214
 215 /*
 216  * initiate connection to a remote socket.
 217  */
 218 static struct socket *ceph_tcp_connect(struct ceph_connection *con)
 219 {
 220         struct sockaddr *paddr = (struct sockaddr *)&con->peer_addr.in_addr;
 221         struct socket *sock;
 222         int ret;
 223
 224         BUG_ON(con->sock);
 225         ret = sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
 226         if (ret)
 227                 return ERR_PTR(ret);
 228         con->sock = sock;
 229         sock->sk->sk_allocation = GFP_NOFS;
 230
 231         set_sock_callbacks(sock, con);
 232
 233         dout("connect %s\n", pr_addr(&con->peer_addr.in_addr));
 234
 235         ret = sock->ops->connect(sock, paddr, sizeof(*paddr), O_NONBLOCK);
 236         if (ret == -EINPROGRESS) {
 237                 dout("connect %s EINPROGRESS sk_state = %u\n",
 238                      pr_addr(&con->peer_addr.in_addr),
 239                      sock->sk->sk_state);
 240                 ret = 0;
 241         }
 242         if (ret < 0) {
 243                 pr_err("connect %s error %d\n",
 244                        pr_addr(&con->peer_addr.in_addr), ret);
 245                 sock_release(sock);
 246                 con->sock = NULL;
 247                 con->error_msg = "connect error";
 248         }
 249
 250         if (ret < 0)
 251                 return ERR_PTR(ret);
 252         return sock;
 253 }
 254
 255 static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
 256 {
 257         struct kvec iov = {buf, len};
 258         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
 259
 260         return kernel_recvmsg(sock, &msg, &iov, 1, len, msg.msg_flags);
 261 }
 262
 263 /*
 264  * write something.  @more is true if caller will be sending more data
 265  * shortly.
 266  */
 267 static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov,
 268                      size_t kvlen, size_t len, int more)
 269 {
 270         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
 271
 272         if (more)
 273                 msg.msg_flags |= MSG_MORE;
 274         else
 275                 msg.msg_flags |= MSG_EOR;  /* superfluous, but what the hell */
 276
 277         return kernel_sendmsg(sock, &msg, iov, kvlen, len);
 278 }
 279
 280
 281 /*
 282  * Shutdown/close the socket for the given connection.
 283  */
 284 static int con_close_socket(struct ceph_connection *con)
 285 {
 286         int rc;
 287
 288         dout("con_close_socket on %p sock %p\n", con, con->sock);
 289         if (!con->sock)
 290                 return 0;
 291         set_bit(SOCK_CLOSED, &con->state);
 292         rc = con->sock->ops->shutdown(con->sock, SHUT_RDWR);
 293         sock_release(con->sock);
 294         con->sock = NULL;
 295         clear_bit(SOCK_CLOSED, &con->state);
 296         return rc;
 297 }
 298
 299 /*
 300  * Reset a connection.  Discard all incoming and outgoing messages
 301  * and clear *_seq state.
 302  */
 303 static void ceph_msg_remove(struct ceph_msg *msg)
 304 {
 305         list_del_init(&msg->list_head);
 306         ceph_msg_put(msg);
 307 }
 308 static void ceph_msg_remove_list(struct list_head *head)
 309 {
 310         while (!list_empty(head)) {
 311                 struct ceph_msg *msg = list_first_entry(head, struct ceph_msg,
 312                                                         list_head);
 313                 ceph_msg_remove(msg);
 314         }
 315 }
 316
 317 static void reset_connection(struct ceph_connection *con)
 318 {
 319         /* reset connection, out_queue, msg_ and connect_seq */
 320         /* discard existing out_queue and msg_seq */
 321         ceph_msg_remove_list(&con->out_queue);
 322         ceph_msg_remove_list(&con->out_sent);
 323
 324         if (con->in_msg) {
 325                 ceph_msg_put(con->in_msg);
 326                 con->in_msg = NULL;
 327         }
 328
 329         con->connect_seq = 0;
 330         con->out_seq = 0;
 331         if (con->out_msg) {
 332                 ceph_msg_put(con->out_msg);
 333                 con->out_msg = NULL;
 334         }
 335         con->in_seq = 0;
 336 }
 337
 338 /*
 339  * mark a peer down.  drop any open connections.
 340  */
 341 void ceph_con_close(struct ceph_connection *con)
 342 {
 343         dout("con_close %p peer %s\n", con, pr_addr(&con->peer_addr.in_addr));
 344         set_bit(CLOSED, &con->state);  /* in case there's queued work */
 345         clear_bit(STANDBY, &con->state);  /* avoid connect_seq bump */
 346         clear_bit(LOSSYTX, &con->state);  /* so we retry next connect */
 347         clear_bit(KEEPALIVE_PENDING, &con->state);
 348         clear_bit(WRITE_PENDING, &con->state);
 349         mutex_lock(&con->mutex);
 350         reset_connection(con);
 351         cancel_delayed_work(&con->work);
 352         mutex_unlock(&con->mutex);
 353         queue_con(con);
 354 }
 355
 356 /*
 357  * Reopen a closed connection, with a new peer address.
 358  */
 359 void ceph_con_open(struct ceph_connection *con, struct ceph_entity_addr *addr)
 360 {
 361         dout("con_open %p %s\n", con, pr_addr(&addr->in_addr));
 362         set_bit(OPENING, &con->state);
 363         clear_bit(CLOSED, &con->state);
 364         memcpy(&con->peer_addr, addr, sizeof(*addr));
 365         con->delay = 0;      /* reset backoff memory */
 366         queue_con(con);
 367 }
 368
 369 /*
 370  * return true if this connection ever successfully opened
 371  */
 372 bool ceph_con_opened(struct ceph_connection *con)
 373 {
 374         return con->connect_seq > 0;
 375 }
 376
 377 /*
 378  * generic get/put
 379  */
 380 struct ceph_connection *ceph_con_get(struct ceph_connection *con)
 381 {
 382         dout("con_get %p nref = %d -> %d\n", con,
 383              atomic_read(&con->nref), atomic_read(&con->nref) + 1);
 384         if (atomic_inc_not_zero(&con->nref))
 385                 return con;
 386         return NULL;
 387 }
 388
 389 void ceph_con_put(struct ceph_connection *con)
 390 {
 391         dout("con_put %p nref = %d -> %d\n", con,
 392              atomic_read(&con->nref), atomic_read(&con->nref) - 1);
 393         BUG_ON(atomic_read(&con->nref) == 0);
 394         if (atomic_dec_and_test(&con->nref)) {
 395                 BUG_ON(con->sock);
 396                 kfree(con);
 397         }
 398 }
 399
 400 /*
 401  * initialize a new connection.
 402  */
 403 void ceph_con_init(struct ceph_messenger *msgr, struct ceph_connection *con)
 404 {
 405         dout("con_init %p\n", con);
 406         memset(con, 0, sizeof(*con));
 407         atomic_set(&con->nref, 1);
 408         con->msgr = msgr;
 409         mutex_init(&con->mutex);
 410         INIT_LIST_HEAD(&con->out_queue);
 411         INIT_LIST_HEAD(&con->out_sent);
 412         INIT_DELAYED_WORK(&con->work, con_work);
 413 }
 414
 415
 416 /*
 417  * We maintain a global counter to order connection attempts.  Get
 418  * a unique seq greater than @gt.
 419  */
 420 static u32 get_global_seq(struct ceph_messenger *msgr, u32 gt)
 421 {
 422         u32 ret;
 423
 424         spin_lock(&msgr->global_seq_lock);
 425         if (msgr->global_seq < gt)
 426                 msgr->global_seq = gt;
 427         ret = ++msgr->global_seq;
 428         spin_unlock(&msgr->global_seq_lock);
 429         return ret;
 430 }
 431
 432
 433 /*
 434  * Prepare footer for currently outgoing message, and finish things
 435  * off.  Assumes out_kvec* are already valid.. we just add on to the end.
 436  */
 437 static void prepare_write_message_footer(struct ceph_connection *con, int v)
 438 {
 439         struct ceph_msg *m = con->out_msg;
 440
 441         dout("prepare_write_message_footer %p\n", con);
 442         con->out_kvec_is_msg = true;
 443         con->out_kvec[v].iov_base = &m->footer;
 444         con->out_kvec[v].iov_len = sizeof(m->footer);
 445         con->out_kvec_bytes += sizeof(m->footer);
 446         con->out_kvec_left++;
 447         con->out_more = m->more_to_follow;
 448         con->out_msg_done = true;
 449 }
 450
 451 /*
 452  * Prepare headers for the next outgoing message.
 453  */
 454 static void prepare_write_message(struct ceph_connection *con)
 455 {
 456         struct ceph_msg *m;
 457         int v = 0;
 458
 459         con->out_kvec_bytes = 0;
 460         con->out_kvec_is_msg = true;
 461         con->out_msg_done = false;
 462
 463         /* Sneak an ack in there first?  If we can get it into the same
 464          * TCP packet that's a good thing. */
 465         if (con->in_seq > con->in_seq_acked) {
 466                 con->in_seq_acked = con->in_seq;
 467                 con->out_kvec[v].iov_base = &tag_ack;
 468                 con->out_kvec[v++].iov_len = 1;
 469                 con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
 470                 con->out_kvec[v].iov_base = &con->out_temp_ack;
 471                 con->out_kvec[v++].iov_len = sizeof(con->out_temp_ack);
 472                 con->out_kvec_bytes = 1 + sizeof(con->out_temp_ack);
 473         }
 474
 475         m = list_first_entry(&con->out_queue,
 476                        struct ceph_msg, list_head);
 477         con->out_msg = m;
 478         if (test_bit(LOSSYTX, &con->state)) {
 479                 list_del_init(&m->list_head);
 480         } else {
 481                 /* put message on sent list */
 482                 ceph_msg_get(m);
 483                 list_move_tail(&m->list_head, &con->out_sent);
 484         }
 485
 486         m->hdr.seq = cpu_to_le64(++con->out_seq);
 487
 488         dout("prepare_write_message %p seq %lld type %d len %d+%d+%d %d pgs\n",
 489              m, con->out_seq, le16_to_cpu(m->hdr.type),
 490              le32_to_cpu(m->hdr.front_len), le32_to_cpu(m->hdr.middle_len),
 491              le32_to_cpu(m->hdr.data_len),
 492              m->nr_pages);
 493         BUG_ON(le32_to_cpu(m->hdr.front_len) != m->front.iov_len);
 494
 495         /* tag + hdr + front + middle */
 496         con->out_kvec[v].iov_base = &tag_msg;
 497         con->out_kvec[v++].iov_len = 1;
 498         con->out_kvec[v].iov_base = &m->hdr;
 499         con->out_kvec[v++].iov_len = sizeof(m->hdr);
 500         con->out_kvec[v++] = m->front;
 501         if (m->middle)
 502                 con->out_kvec[v++] = m->middle->vec;
 503         con->out_kvec_left = v;
 504         con->out_kvec_bytes += 1 + sizeof(m->hdr) + m->front.iov_len +
 505                 (m->middle ? m->middle->vec.iov_len : 0);
 506         con->out_kvec_cur = con->out_kvec;
 507
 508         /* fill in crc (except data pages), footer */
 509         con->out_msg->hdr.crc =
 510                 cpu_to_le32(crc32c(0, (void *)&m->hdr,
 511                                       sizeof(m->hdr) - sizeof(m->hdr.crc)));
 512         con->out_msg->footer.flags = CEPH_MSG_FOOTER_COMPLETE;
 513         con->out_msg->footer.front_crc =
 514                 cpu_to_le32(crc32c(0, m->front.iov_base, m->front.iov_len));
 515         if (m->middle)
 516                 con->out_msg->footer.middle_crc =
 517                         cpu_to_le32(crc32c(0, m->middle->vec.iov_base,
 518                                            m->middle->vec.iov_len));
 519         else
 520                 con->out_msg->footer.middle_crc = 0;
 521         con->out_msg->footer.data_crc = 0;
 522         dout("prepare_write_message front_crc %u data_crc %u\n",
 523              le32_to_cpu(con->out_msg->footer.front_crc),
 524              le32_to_cpu(con->out_msg->footer.middle_crc));
 525
 526         /* is there a data payload? */
 527         if (le32_to_cpu(m->hdr.data_len) > 0) {
 528                 /* initialize page iterator */
 529                 con->out_msg_pos.page = 0;
 530                 con->out_msg_pos.page_pos =
 531                         le16_to_cpu(m->hdr.data_off) & ~PAGE_MASK;
 532                 con->out_msg_pos.data_pos = 0;
 533                 con->out_msg_pos.did_page_crc = 0;
 534                 con->out_more = 1;  /* data + footer will follow */
 535         } else {
 536                 /* no, queue up footer too and be done */
 537                 prepare_write_message_footer(con, v);
 538         }
 539
 540         set_bit(WRITE_PENDING, &con->state);
 541 }
 542
 543 /*
 544  * Prepare an ack.
 545  */
 546 static void prepare_write_ack(struct ceph_connection *con)
 547 {
 548         dout("prepare_write_ack %p %llu -> %llu\n", con,
 549              con->in_seq_acked, con->in_seq);
 550         con->in_seq_acked = con->in_seq;
 551
 552         con->out_kvec[0].iov_base = &tag_ack;
 553         con->out_kvec[0].iov_len = 1;
 554         con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
 555         con->out_kvec[1].iov_base = &con->out_temp_ack;
 556         con->out_kvec[1].iov_len = sizeof(con->out_temp_ack);
 557         con->out_kvec_left = 2;
 558         con->out_kvec_bytes = 1 + sizeof(con->out_temp_ack);
 559         con->out_kvec_cur = con->out_kvec;
 560         con->out_more = 1;  /* more will follow.. eventually.. */
 561         set_bit(WRITE_PENDING, &con->state);
 562 }
 563
 564 /*
 565  * Prepare to write keepalive byte.
 566  */
 567 static void prepare_write_keepalive(struct ceph_connection *con)
 568 {
 569         dout("prepare_write_keepalive %p\n", con);
 570         con->out_kvec[0].iov_base = &tag_keepalive;
 571         con->out_kvec[0].iov_len = 1;
 572         con->out_kvec_left = 1;
 573         con->out_kvec_bytes = 1;
 574         con->out_kvec_cur = con->out_kvec;
 575         set_bit(WRITE_PENDING, &con->state);
 576 }
 577
 578 /*
 579  * Connection negotiation.
 580  */
 581
 582 static void prepare_connect_authorizer(struct ceph_connection *con)
 583 {
 584         void *auth_buf;
 585         int auth_len = 0;
 586         int auth_protocol = 0;
 587
 588         mutex_unlock(&con->mutex);
 589         if (con->ops->get_authorizer)
 590                 con->ops->get_authorizer(con, &auth_buf, &auth_len,
 591                                          &auth_protocol, &con->auth_reply_buf,
 592                                          &con->auth_reply_buf_len,
 593                                          con->auth_retry);
 594         mutex_lock(&con->mutex);
 595
 596         con->out_connect.authorizer_protocol = cpu_to_le32(auth_protocol);
 597         con->out_connect.authorizer_len = cpu_to_le32(auth_len);
 598
 599         con->out_kvec[con->out_kvec_left].iov_base = auth_buf;
 600         con->out_kvec[con->out_kvec_left].iov_len = auth_len;
 601         con->out_kvec_left++;
 602         con->out_kvec_bytes += auth_len;
 603 }
 604
 605 /*
 606  * We connected to a peer and are saying hello.
 607  */
 608 static void prepare_write_banner(struct ceph_messenger *msgr,
 609                                  struct ceph_connection *con)
 610 {
 611         int len = strlen(CEPH_BANNER);
 612
 613         con->out_kvec[0].iov_base = CEPH_BANNER;
 614         con->out_kvec[0].iov_len = len;
 615         con->out_kvec[1].iov_base = &msgr->my_enc_addr;
 616         con->out_kvec[1].iov_len = sizeof(msgr->my_enc_addr);
 617         con->out_kvec_left = 2;
 618         con->out_kvec_bytes = len + sizeof(msgr->my_enc_addr);
 619         con->out_kvec_cur = con->out_kvec;
 620         con->out_more = 0;
 621         set_bit(WRITE_PENDING, &con->state);
 622 }
 623
 624 static void prepare_write_connect(struct ceph_messenger *msgr,
 625                                   struct ceph_connection *con,
 626                                   int after_banner)
 627 {
 628         unsigned global_seq = get_global_seq(con->msgr, 0);
 629         int proto;
 630
 631         switch (con->peer_name.type) {
 632         case CEPH_ENTITY_TYPE_MON:
 633                 proto = CEPH_MONC_PROTOCOL;
 634                 break;
 635         case CEPH_ENTITY_TYPE_OSD:
 636                 proto = CEPH_OSDC_PROTOCOL;
 637                 break;
 638         case CEPH_ENTITY_TYPE_MDS:
 639                 proto = CEPH_MDSC_PROTOCOL;
 640                 break;
 641         default:
 642                 BUG();
 643         }
 644
 645         dout("prepare_write_connect %p cseq=%d gseq=%d proto=%d\n", con,
 646              con->connect_seq, global_seq, proto);
 647
 648         con->out_connect.features = CEPH_FEATURE_SUPPORTED;
 649         con->out_connect.host_type = cpu_to_le32(CEPH_ENTITY_TYPE_CLIENT);
 650         con->out_connect.connect_seq = cpu_to_le32(con->connect_seq);
 651         con->out_connect.global_seq = cpu_to_le32(global_seq);
 652         con->out_connect.protocol_version = cpu_to_le32(proto);
 653         con->out_connect.flags = 0;
 654
 655         if (!after_banner) {
 656                 con->out_kvec_left = 0;
 657                 con->out_kvec_bytes = 0;
 658         }
 659         con->out_kvec[con->out_kvec_left].iov_base = &con->out_connect;
 660         con->out_kvec[con->out_kvec_left].iov_len = sizeof(con->out_connect);
 661         con->out_kvec_left++;
 662         con->out_kvec_bytes += sizeof(con->out_connect);
 663         con->out_kvec_cur = con->out_kvec;
 664         con->out_more = 0;
 665         set_bit(WRITE_PENDING, &con->state);
 666
 667         prepare_connect_authorizer(con);
 668 }
 669
 670
 671 /*
 672  * write as much of pending kvecs to the socket as we can.
 673  *  1 -> done
 674  *  0 -> socket full, but more to do
 675  * <0 -> error
 676  */
 677 static int write_partial_kvec(struct ceph_connection *con)
 678 {
 679         int ret;
 680
 681         dout("write_partial_kvec %p %d left\n", con, con->out_kvec_bytes);
 682         while (con->out_kvec_bytes > 0) {
 683                 ret = ceph_tcp_sendmsg(con->sock, con->out_kvec_cur,
 684                                        con->out_kvec_left, con->out_kvec_bytes,
 685                                        con->out_more);
 686                 if (ret <= 0)
 687                         goto out;
 688                 con->out_kvec_bytes -= ret;
 689                 if (con->out_kvec_bytes == 0)
 690                         break;            /* done */
 691                 while (ret > 0) {
 692                         if (ret >= con->out_kvec_cur->iov_len) {
 693                                 ret -= con->out_kvec_cur->iov_len;
 694                                 con->out_kvec_cur++;
 695                                 con->out_kvec_left--;
 696                         } else {
 697                                 con->out_kvec_cur->iov_len -= ret;
 698                                 con->out_kvec_cur->iov_base += ret;
 699                                 ret = 0;
 700                                 break;
 701                         }
 702                 }
 703         }
 704         con->out_kvec_left = 0;
 705         con->out_kvec_is_msg = false;
 706         ret = 1;
 707 out:
 708         dout("write_partial_kvec %p %d left in %d kvecs ret = %d\n", con,
 709              con->out_kvec_bytes, con->out_kvec_left, ret);
 710         return ret;  /* done! */
 711 }
 712
 713 /*
 714  * Write as much message data payload as we can.  If we finish, queue
 715  * up the footer.
 716  *  1 -> done, footer is now queued in out_kvec[].
 717  *  0 -> socket full, but more to do
 718  * <0 -> error
 719  */
 720 static int write_partial_msg_pages(struct ceph_connection *con)
 721 {
 722         struct ceph_msg *msg = con->out_msg;
 723         unsigned data_len = le32_to_cpu(msg->hdr.data_len);
 724         size_t len;
 725         int crc = con->msgr->nocrc;
 726         int ret;
 727
 728         dout("write_partial_msg_pages %p msg %p page %d/%d offset %d\n",
 729              con, con->out_msg, con->out_msg_pos.page, con->out_msg->nr_pages,
 730              con->out_msg_pos.page_pos);
 731
 732         while (con->out_msg_pos.page < con->out_msg->nr_pages) {
 733                 struct page *page = NULL;
 734                 void *kaddr = NULL;
 735
 736                 /*
 737                  * if we are calculating the data crc (the default), we need
 738                  * to map the page.  if our pages[] has been revoked, use the
 739                  * zero page.
 740                  */
 741                 if (msg->pages) {
 742                         page = msg->pages[con->out_msg_pos.page];
 743                         if (crc)
 744                                 kaddr = kmap(page);
 745                 } else if (msg->pagelist) {
 746                         page = list_first_entry(&msg->pagelist->head,
 747                                                 struct page, lru);
 748                         if (crc)
 749                                 kaddr = kmap(page);
 750                 } else {
 751                         page = con->msgr->zero_page;
 752                         if (crc)
 753                                 kaddr = page_address(con->msgr->zero_page);
 754                 }
 755                 len = min((int)(PAGE_SIZE - con->out_msg_pos.page_pos),
 756                           (int)(data_len - con->out_msg_pos.data_pos));
 757                 if (crc && !con->out_msg_pos.did_page_crc) {
 758                         void *base = kaddr + con->out_msg_pos.page_pos;
 759                         u32 tmpcrc = le32_to_cpu(con->out_msg->footer.data_crc);
 760
 761                         BUG_ON(kaddr == NULL);
 762                         con->out_msg->footer.data_crc =
 763                                 cpu_to_le32(crc32c(tmpcrc, base, len));
 764                         con->out_msg_pos.did_page_crc = 1;
 765                 }
 766
 767                 ret = kernel_sendpage(con->sock, page,
 768                                       con->out_msg_pos.page_pos, len,
 769                                       MSG_DONTWAIT | MSG_NOSIGNAL |
 770                                       MSG_MORE);
 771
 772                 if (crc && (msg->pages || msg->pagelist))
 773                         kunmap(page);
 774
 775                 if (ret <= 0)
 776                         goto out;
 777
 778                 con->out_msg_pos.data_pos += ret;
 779                 con->out_msg_pos.page_pos += ret;
 780                 if (ret == len) {
 781                         con->out_msg_pos.page_pos = 0;
 782                         con->out_msg_pos.page++;
 783                         con->out_msg_pos.did_page_crc = 0;
 784                         if (msg->pagelist)
 785                                 list_move_tail(&page->lru,
 786                                                &msg->pagelist->head);
 787                 }
 788         }
 789
 790         dout("write_partial_msg_pages %p msg %p done\n", con, msg);
 791
 792         /* prepare and queue up footer, too */
 793         if (!crc)
 794                 con->out_msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
 795         con->out_kvec_bytes = 0;
 796         con->out_kvec_left = 0;
 797         con->out_kvec_cur = con->out_kvec;
 798         prepare_write_message_footer(con, 0);
 799         ret = 1;
 800 out:
 801         return ret;
 802 }
 803
 804 /*
 805  * write some zeros
 806  */
 807 static int write_partial_skip(struct ceph_connection *con)
 808 {
 809         int ret;
 810
 811         while (con->out_skip > 0) {
 812                 struct kvec iov = {
 813                         .iov_base = page_address(con->msgr->zero_page),
 814                         .iov_len = min(con->out_skip, (int)PAGE_CACHE_SIZE)
 815                 };
 816
 817                 ret = ceph_tcp_sendmsg(con->sock, &iov, 1, iov.iov_len, 1);
 818                 if (ret <= 0)
 819                         goto out;
 820                 con->out_skip -= ret;
 821         }
 822         ret = 1;
 823 out:
 824         return ret;
 825 }
 826
 827 /*
 828  * Prepare to read connection handshake, or an ack.
 829  */
 830 static void prepare_read_banner(struct ceph_connection *con)
 831 {
 832         dout("prepare_read_banner %p\n", con);
 833         con->in_base_pos = 0;
 834 }
 835
 836 static void prepare_read_connect(struct ceph_connection *con)
 837 {
 838         dout("prepare_read_connect %p\n", con);
 839         con->in_base_pos = 0;
 840 }
 841
 842 static void prepare_read_ack(struct ceph_connection *con)
 843 {
 844         dout("prepare_read_ack %p\n", con);
 845         con->in_base_pos = 0;
 846 }
 847
 848 static void prepare_read_tag(struct ceph_connection *con)
 849 {
 850         dout("prepare_read_tag %p\n", con);
 851         con->in_base_pos = 0;
 852         con->in_tag = CEPH_MSGR_TAG_READY;
 853 }
 854
 855 /*
 856  * Prepare to read a message.
 857  */
 858 static int prepare_read_message(struct ceph_connection *con)
 859 {
 860         dout("prepare_read_message %p\n", con);
 861         BUG_ON(con->in_msg != NULL);
 862         con->in_base_pos = 0;
 863         con->in_front_crc = con->in_middle_crc = con->in_data_crc = 0;
 864         return 0;
 865 }
 866
 867
 868 static int read_partial(struct ceph_connection *con,
 869                         int *to, int size, void *object)
 870 {
 871         *to += size;
 872         while (con->in_base_pos < *to) {
 873                 int left = *to - con->in_base_pos;
 874                 int have = size - left;
 875                 int ret = ceph_tcp_recvmsg(con->sock, object + have, left);
 876                 if (ret <= 0)
 877                         return ret;
 878                 con->in_base_pos += ret;
 879         }
 880         return 1;
 881 }
 882
 883
 884 /*
 885  * Read all or part of the connect-side handshake on a new connection
 886  */
 887 static int read_partial_banner(struct ceph_connection *con)
 888 {
 889         int ret, to = 0;
 890
 891         dout("read_partial_banner %p at %d\n", con, con->in_base_pos);
 892
 893         /* peer's banner */
 894         ret = read_partial(con, &to, strlen(CEPH_BANNER), con->in_banner);
 895         if (ret <= 0)
 896                 goto out;
 897         ret = read_partial(con, &to, sizeof(con->actual_peer_addr),
 898                            &con->actual_peer_addr);
 899         if (ret <= 0)
 900                 goto out;
 901         ret = read_partial(con, &to, sizeof(con->peer_addr_for_me),
 902                            &con->peer_addr_for_me);
 903         if (ret <= 0)
 904                 goto out;
 905 out:
 906         return ret;
 907 }
 908
 909 static int read_partial_connect(struct ceph_connection *con)
 910 {
 911         int ret, to = 0;
 912
 913         dout("read_partial_connect %p at %d\n", con, con->in_base_pos);
 914
 915         ret = read_partial(con, &to, sizeof(con->in_reply), &con->in_reply);
 916         if (ret <= 0)
 917                 goto out;
 918         ret = read_partial(con, &to, le32_to_cpu(con->in_reply.authorizer_len),
 919                            con->auth_reply_buf);
 920         if (ret <= 0)
 921                 goto out;
 922
 923         dout("read_partial_connect %p tag %d, con_seq = %u, g_seq = %u\n",
 924              con, (int)con->in_reply.tag,
 925              le32_to_cpu(con->in_reply.connect_seq),
 926              le32_to_cpu(con->in_reply.global_seq));
 927 out:
 928         return ret;
 929
 930 }
 931
 932 /*
 933  * Verify the hello banner looks okay.
 934  */
 935 static int verify_hello(struct ceph_connection *con)
 936 {
 937         if (memcmp(con->in_banner, CEPH_BANNER, strlen(CEPH_BANNER))) {
 938                 pr_err("connect to %s got bad banner\n",
 939                        pr_addr(&con->peer_addr.in_addr));
 940                 con->error_msg = "protocol error, bad banner";
 941                 return -1;
 942         }
 943         return 0;
 944 }
 945
 946 static bool addr_is_blank(struct sockaddr_storage *ss)
 947 {
 948         switch (ss->ss_family) {
 949         case AF_INET:
 950                 return ((struct sockaddr_in *)ss)->sin_addr.s_addr == 0;
 951         case AF_INET6:
 952                 return
 953                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[0] == 0 &&
 954                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[1] == 0 &&
 955                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[2] == 0 &&
 956                      ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[3] == 0;
 957         }
 958         return false;
 959 }
 960
 961 static int addr_port(struct sockaddr_storage *ss)
 962 {
 963         switch (ss->ss_family) {
 964         case AF_INET:
 965                 return ntohs(((struct sockaddr_in *)ss)->sin_port);
 966         case AF_INET6:
 967                 return ntohs(((struct sockaddr_in6 *)ss)->sin6_port);
 968         }
 969         return 0;
 970 }
 971
 972 static void addr_set_port(struct sockaddr_storage *ss, int p)
 973 {
 974         switch (ss->ss_family) {
 975         case AF_INET:
 976                 ((struct sockaddr_in *)ss)->sin_port = htons(p);
 977         case AF_INET6:
 978                 ((struct sockaddr_in6 *)ss)->sin6_port = htons(p);
 979         }
 980 }
 981
 982 /*
 983  * Parse an ip[:port] list into an addr array.  Use the default
 984  * monitor port if a port isn't specified.
 985  */
 986 int ceph_parse_ips(const char *c, const char *end,
 987                    struct ceph_entity_addr *addr,
 988                    int max_count, int *count)
 989 {
 990         int i;
 991         const char *p = c;
 992
 993         dout("parse_ips on '%.*s'\n", (int)(end-c), c);
 994         for (i = 0; i < max_count; i++) {
 995                 const char *ipend;
 996                 struct sockaddr_storage *ss = &addr[i].in_addr;
 997                 struct sockaddr_in *in4 = (void *)ss;
 998                 struct sockaddr_in6 *in6 = (void *)ss;
 999                 int port;
1000
1001                 memset(ss, 0, sizeof(*ss));
1002                 if (in4_pton(p, end - p, (u8 *)&in4->sin_addr.s_addr,
1003                              ',', &ipend)) {
1004                         ss->ss_family = AF_INET;
1005                 } else if (in6_pton(p, end - p, (u8 *)&in6->sin6_addr.s6_addr,
1006                                     ',', &ipend)) {
1007                         ss->ss_family = AF_INET6;
1008                 } else {
1009                         goto bad;
1010                 }
1011                 p = ipend;
1012
1013                 /* port? */
1014                 if (p < end && *p == ':') {
1015                         port = 0;
1016                         p++;
1017                         while (p < end && *p >= '0' && *p <= '9') {
1018                                 port = (port * 10) + (*p - '0');
1019                                 p++;
1020                         }
1021                         if (port > 65535 || port == 0)
1022                                 goto bad;
1023                 } else {
1024                         port = CEPH_MON_PORT;
1025                 }
1026
1027                 addr_set_port(ss, port);
1028
1029                 dout("parse_ips got %s\n", pr_addr(ss));
1030
1031                 if (p == end)
1032                         break;
1033                 if (*p != ',')
1034                         goto bad;
1035                 p++;
1036         }
1037
1038         if (p != end)
1039                 goto bad;
1040
1041         if (count)
1042                 *count = i + 1;
1043         return 0;
1044
1045 bad:
1046         pr_err("parse_ips bad ip '%s'\n", c);
1047         return -EINVAL;
1048 }
1049
1050 static int process_banner(struct ceph_connection *con)
1051 {
1052         dout("process_banner on %p\n", con);
1053
1054         if (verify_hello(con) < 0)
1055                 return -1;
1056
1057         ceph_decode_addr(&con->actual_peer_addr);
1058         ceph_decode_addr(&con->peer_addr_for_me);
1059
1060         /*
1061          * Make sure the other end is who we wanted.  note that the other
1062          * end may not yet know their ip address, so if it's 0.0.0.0, give
1063          * them the benefit of the doubt.
1064          */
1065         if (memcmp(&con->peer_addr, &con->actual_peer_addr,
1066                    sizeof(con->peer_addr)) != 0 &&
1067             !(addr_is_blank(&con->actual_peer_addr.in_addr) &&
1068               con->actual_peer_addr.nonce == con->peer_addr.nonce)) {
1069                 pr_warning("wrong peer, want %s/%lld, got %s/%lld\n",
1070                            pr_addr(&con->peer_addr.in_addr),
1071                            le64_to_cpu(con->peer_addr.nonce),
1072                            pr_addr(&con->actual_peer_addr.in_addr),
1073                            le64_to_cpu(con->actual_peer_addr.nonce));
1074                 con->error_msg = "wrong peer at address";
1075                 return -1;
1076         }
1077
1078         /*
1079          * did we learn our address?
1080          */
1081         if (addr_is_blank(&con->msgr->inst.addr.in_addr)) {
1082                 int port = addr_port(&con->msgr->inst.addr.in_addr);
1083
1084                 memcpy(&con->msgr->inst.addr.in_addr,
1085                        &con->peer_addr_for_me.in_addr,
1086                        sizeof(con->peer_addr_for_me.in_addr));
1087                 addr_set_port(&con->msgr->inst.addr.in_addr, port);
1088                 encode_my_addr(con->msgr);
1089                 dout("process_banner learned my addr is %s\n",
1090                      pr_addr(&con->msgr->inst.addr.in_addr));
1091         }
1092
1093         set_bit(NEGOTIATING, &con->state);
1094         prepare_read_connect(con);
1095         return 0;
1096 }
1097
1098 static void fail_protocol(struct ceph_connection *con)
1099 {
1100         reset_connection(con);
1101         set_bit(CLOSED, &con->state);  /* in case there's queued work */
1102
1103         mutex_unlock(&con->mutex);
1104         if (con->ops->bad_proto)
1105                 con->ops->bad_proto(con);
1106         mutex_lock(&con->mutex);
1107 }
1108
1109 static int process_connect(struct ceph_connection *con)
1110 {
1111         u64 sup_feat = CEPH_FEATURE_SUPPORTED;
1112         u64 req_feat = CEPH_FEATURE_REQUIRED;
1113         u64 server_feat = le64_to_cpu(con->in_reply.features);
1114
1115         dout("process_connect on %p tag %d\n", con, (int)con->in_tag);
1116
1117         switch (con->in_reply.tag) {
1118         case CEPH_MSGR_TAG_FEATURES:
1119                 pr_err("%s%lld %s feature set mismatch,"
1120                        " my %llx < server's %llx, missing %llx\n",
1121                        ENTITY_NAME(con->peer_name),
1122                        pr_addr(&con->peer_addr.in_addr),
1123                        sup_feat, server_feat, server_feat & ~sup_feat);
1124                 con->error_msg = "missing required protocol features";
1125                 fail_protocol(con);
1126                 return -1;
1127
1128         case CEPH_MSGR_TAG_BADPROTOVER:
1129                 pr_err("%s%lld %s protocol version mismatch,"
1130                        " my %d != server's %d\n",
1131                        ENTITY_NAME(con->peer_name),
1132                        pr_addr(&con->peer_addr.in_addr),
1133                        le32_to_cpu(con->out_connect.protocol_version),
1134                        le32_to_cpu(con->in_reply.protocol_version));
1135                 con->error_msg = "protocol version mismatch";
1136                 fail_protocol(con);
1137                 return -1;
1138
1139         case CEPH_MSGR_TAG_BADAUTHORIZER:
1140                 con->auth_retry++;
1141                 dout("process_connect %p got BADAUTHORIZER attempt %d\n", con,
1142                      con->auth_retry);
1143                 if (con->auth_retry == 2) {
1144                         con->error_msg = "connect authorization failure";
1145                         reset_connection(con);
1146                         set_bit(CLOSED, &con->state);
1147                         return -1;
1148                 }
1149                 con->auth_retry = 1;
1150                 prepare_write_connect(con->msgr, con, 0);
1151                 prepare_read_connect(con);
1152                 break;
1153
1154         case CEPH_MSGR_TAG_RESETSESSION:
1155                 /*
1156                  * If we connected with a large connect_seq but the peer
1157                  * has no record of a session with us (no connection, or
1158                  * connect_seq == 0), they will send RESETSESION to indicate
1159                  * that they must have reset their session, and may have
1160                  * dropped messages.
1161                  */
1162                 dout("process_connect got RESET peer seq %u\n",
1163                      le32_to_cpu(con->in_connect.connect_seq));
1164                 pr_err("%s%lld %s connection reset\n",
1165                        ENTITY_NAME(con->peer_name),
1166                        pr_addr(&con->peer_addr.in_addr));
1167                 reset_connection(con);
1168                 prepare_write_connect(con->msgr, con, 0);
1169                 prepare_read_connect(con);
1170
1171                 /* Tell ceph about it. */
1172                 mutex_unlock(&con->mutex);
1173                 pr_info("reset on %s%lld\n", ENTITY_NAME(con->peer_name));
1174                 if (con->ops->peer_reset)
1175                         con->ops->peer_reset(con);
1176                 mutex_lock(&con->mutex);
1177                 break;
1178
1179         case CEPH_MSGR_TAG_RETRY_SESSION:
1180                 /*
1181                  * If we sent a smaller connect_seq than the peer has, try
1182                  * again with a larger value.
1183                  */
1184                 dout("process_connect got RETRY my seq = %u, peer_seq = %u\n",
1185                      le32_to_cpu(con->out_connect.connect_seq),
1186                      le32_to_cpu(con->in_connect.connect_seq));
1187                 con->connect_seq = le32_to_cpu(con->in_connect.connect_seq);
1188                 prepare_write_connect(con->msgr, con, 0);
1189                 prepare_read_connect(con);
1190                 break;
1191
1192         case CEPH_MSGR_TAG_RETRY_GLOBAL:
1193                 /*
1194                  * If we sent a smaller global_seq than the peer has, try
1195                  * again with a larger value.
1196                  */
1197                 dout("process_connect got RETRY_GLOBAL my %u peer_gseq %u\n",
1198                      con->peer_global_seq,
1199                      le32_to_cpu(con->in_connect.global_seq));
1200                 get_global_seq(con->msgr,
1201                                le32_to_cpu(con->in_connect.global_seq));
1202                 prepare_write_connect(con->msgr, con, 0);
1203                 prepare_read_connect(con);
1204                 break;
1205
1206         case CEPH_MSGR_TAG_READY:
1207                 if (req_feat & ~server_feat) {
1208                         pr_err("%s%lld %s protocol feature mismatch,"
1209                                " my required %llx > server's %llx, need %llx\n",
1210                                ENTITY_NAME(con->peer_name),
1211                                pr_addr(&con->peer_addr.in_addr),
1212                                req_feat, server_feat, req_feat & ~server_feat);
1213                         con->error_msg = "missing required protocol features";
1214                         fail_protocol(con);
1215                         return -1;
1216                 }
1217                 clear_bit(CONNECTING, &con->state);
1218                 con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
1219                 con->connect_seq++;
1220                 dout("process_connect got READY gseq %d cseq %d (%d)\n",
1221                      con->peer_global_seq,
1222                      le32_to_cpu(con->in_reply.connect_seq),
1223                      con->connect_seq);
1224                 WARN_ON(con->connect_seq !=
1225                         le32_to_cpu(con->in_reply.connect_seq));
1226
1227                 if (con->in_reply.flags & CEPH_MSG_CONNECT_LOSSY)
1228                         set_bit(LOSSYTX, &con->state);
1229
1230                 prepare_read_tag(con);
1231                 break;
1232
1233         case CEPH_MSGR_TAG_WAIT:
1234                 /*
1235                  * If there is a connection race (we are opening
1236                  * connections to each other), one of us may just have
1237                  * to WAIT.  This shouldn't happen if we are the
1238                  * client.
1239                  */
1240                 pr_err("process_connect peer connecting WAIT\n");
1241
1242         default:
1243                 pr_err("connect protocol error, will retry\n");
1244                 con->error_msg = "protocol error, garbage tag during connect";
1245                 return -1;
1246         }
1247         return 0;
1248 }
1249
1250
1251 /*
1252  * read (part of) an ack
1253  */
1254 static int read_partial_ack(struct ceph_connection *con)
1255 {
1256         int to = 0;
1257
1258         return read_partial(con, &to, sizeof(con->in_temp_ack),
1259                             &con->in_temp_ack);
1260 }
1261
1262
1263 /*
1264  * We can finally discard anything that's been acked.
1265  */
1266 static void process_ack(struct ceph_connection *con)
1267 {
1268         struct ceph_msg *m;
1269         u64 ack = le64_to_cpu(con->in_temp_ack);
1270         u64 seq;
1271
1272         while (!list_empty(&con->out_sent)) {
1273                 m = list_first_entry(&con->out_sent, struct ceph_msg,
1274                                      list_head);
1275                 seq = le64_to_cpu(m->hdr.seq);
1276                 if (seq > ack)
1277                         break;
1278                 dout("got ack for seq %llu type %d at %p\n", seq,
1279                      le16_to_cpu(m->hdr.type), m);
1280                 ceph_msg_remove(m);
1281         }
1282         prepare_read_tag(con);
1283 }
1284
1285
1286
1287
1288 static int read_partial_message_section(struct ceph_connection *con,
1289                                         struct kvec *section, unsigned int sec_len,
1290                                         u32 *crc)
1291 {
1292         int left;
1293         int ret;
1294
1295         BUG_ON(!section);
1296
1297         while (section->iov_len < sec_len) {
1298                 BUG_ON(section->iov_base == NULL);
1299                 left = sec_len - section->iov_len;
1300                 ret = ceph_tcp_recvmsg(con->sock, (char *)section->iov_base +
1301                                        section->iov_len, left);
1302                 if (ret <= 0)
1303                         return ret;
1304                 section->iov_len += ret;
1305                 if (section->iov_len == sec_len)
1306                         *crc = crc32c(0, section->iov_base,
1307                                       section->iov_len);
1308         }
1309
1310         return 1;
1311 }
1312
1313 static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
1314                                 struct ceph_msg_header *hdr,
1315                                 int *skip);
1316 /*
1317  * read (part of) a message.
1318  */
1319 static int read_partial_message(struct ceph_connection *con)
1320 {
1321         struct ceph_msg *m = con->in_msg;
1322         void *p;
1323         int ret;
1324         int to, left;
1325         unsigned front_len, middle_len, data_len, data_off;
1326         int datacrc = con->msgr->nocrc;
1327         int skip;
1328
1329         dout("read_partial_message con %p msg %p\n", con, m);
1330
1331         /* header */
1332         while (con->in_base_pos < sizeof(con->in_hdr)) {
1333                 left = sizeof(con->in_hdr) - con->in_base_pos;
1334                 ret = ceph_tcp_recvmsg(con->sock,
1335                                        (char *)&con->in_hdr + con->in_base_pos,
1336                                        left);
1337                 if (ret <= 0)
1338                         return ret;
1339                 con->in_base_pos += ret;
1340                 if (con->in_base_pos == sizeof(con->in_hdr)) {
1341                         u32 crc = crc32c(0, (void *)&con->in_hdr,
1342                                  sizeof(con->in_hdr) - sizeof(con->in_hdr.crc));
1343                         if (crc != le32_to_cpu(con->in_hdr.crc)) {
1344                                 pr_err("read_partial_message bad hdr "
1345                                        " crc %u != expected %u\n",
1346                                        crc, con->in_hdr.crc);
1347                                 return -EBADMSG;
1348                         }
1349                 }
1350         }
1351         front_len = le32_to_cpu(con->in_hdr.front_len);
1352         if (front_len > CEPH_MSG_MAX_FRONT_LEN)
1353                 return -EIO;
1354         middle_len = le32_to_cpu(con->in_hdr.middle_len);
1355         if (middle_len > CEPH_MSG_MAX_DATA_LEN)
1356                 return -EIO;
1357         data_len = le32_to_cpu(con->in_hdr.data_len);
1358         if (data_len > CEPH_MSG_MAX_DATA_LEN)
1359                 return -EIO;
1360         data_off = le16_to_cpu(con->in_hdr.data_off);
1361
1362         /* allocate message? */
1363         if (!con->in_msg) {
1364                 dout("got hdr type %d front %d data %d\n", con->in_hdr.type,
1365                      con->in_hdr.front_len, con->in_hdr.data_len);
1366                 con->in_msg = ceph_alloc_msg(con, &con->in_hdr, &skip);
1367                 if (skip) {
1368                         /* skip this message */
1369                         dout("alloc_msg returned NULL, skipping message\n");
1370                         con->in_base_pos = -front_len - middle_len - data_len -
1371                                 sizeof(m->footer);
1372                         con->in_tag = CEPH_MSGR_TAG_READY;
1373                         return 0;
1374                 }
1375                 if (IS_ERR(con->in_msg)) {
1376                         ret = PTR_ERR(con->in_msg);
1377                         con->in_msg = NULL;
1378                         con->error_msg =
1379                                 "error allocating memory for incoming message";
1380                         return ret;
1381                 }
1382                 m = con->in_msg;
1383                 m->front.iov_len = 0;    /* haven't read it yet */
1384                 if (m->middle)
1385                         m->middle->vec.iov_len = 0;
1386
1387                 con->in_msg_pos.page = 0;
1388                 con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;
1389                 con->in_msg_pos.data_pos = 0;
1390         }
1391
1392         /* front */
1393         ret = read_partial_message_section(con, &m->front, front_len,
1394                                            &con->in_front_crc);
1395         if (ret <= 0)
1396                 return ret;
1397
1398         /* middle */
1399         if (m->middle) {
1400                 ret = read_partial_message_section(con, &m->middle->vec, middle_len,
1401                                                    &con->in_middle_crc);
1402                 if (ret <= 0)
1403                         return ret;
1404         }
1405
1406         /* (page) data */
1407         while (con->in_msg_pos.data_pos < data_len) {
1408                 left = min((int)(data_len - con->in_msg_pos.data_pos),
1409                            (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
1410                 BUG_ON(m->pages == NULL);
1411                 p = kmap(m->pages[con->in_msg_pos.page]);
1412                 ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
1413                                        left);
1414                 if (ret > 0 && datacrc)
1415                         con->in_data_crc =
1416                                 crc32c(con->in_data_crc,
1417                                           p + con->in_msg_pos.page_pos, ret);
1418                 kunmap(m->pages[con->in_msg_pos.page]);
1419                 if (ret <= 0)
1420                         return ret;
1421                 con->in_msg_pos.data_pos += ret;
1422                 con->in_msg_pos.page_pos += ret;
1423                 if (con->in_msg_pos.page_pos == PAGE_SIZE) {
1424                         con->in_msg_pos.page_pos = 0;
1425                         con->in_msg_pos.page++;
1426                 }
1427         }
1428
1429         /* footer */
1430         to = sizeof(m->hdr) + sizeof(m->footer);
1431         while (con->in_base_pos < to) {
1432                 left = to - con->in_base_pos;
1433                 ret = ceph_tcp_recvmsg(con->sock, (char *)&m->footer +
1434                                        (con->in_base_pos - sizeof(m->hdr)),
1435                                        left);
1436                 if (ret <= 0)
1437                         return ret;
1438                 con->in_base_pos += ret;
1439         }
1440         dout("read_partial_message got msg %p %d (%u) + %d (%u) + %d (%u)\n",
1441              m, front_len, m->footer.front_crc, middle_len,
1442              m->footer.middle_crc, data_len, m->footer.data_crc);
1443
1444         /* crc ok? */
1445         if (con->in_front_crc != le32_to_cpu(m->footer.front_crc)) {
1446                 pr_err("read_partial_message %p front crc %u != exp. %u\n",
1447                        m, con->in_front_crc, m->footer.front_crc);
1448                 return -EBADMSG;
1449         }
1450         if (con->in_middle_crc != le32_to_cpu(m->footer.middle_crc)) {
1451                 pr_err("read_partial_message %p middle crc %u != exp %u\n",
1452                        m, con->in_middle_crc, m->footer.middle_crc);
1453                 return -EBADMSG;
1454         }
1455         if (datacrc &&
1456             (m->footer.flags & CEPH_MSG_FOOTER_NOCRC) == 0 &&
1457             con->in_data_crc != le32_to_cpu(m->footer.data_crc)) {
1458                 pr_err("read_partial_message %p data crc %u != exp. %u\n", m,
1459                        con->in_data_crc, le32_to_cpu(m->footer.data_crc));
1460                 return -EBADMSG;
1461         }
1462
1463         return 1; /* done! */
1464 }
1465
1466 /*
1467  * Process message.  This happens in the worker thread.  The callback should
1468  * be careful not to do anything that waits on other incoming messages or it
1469  * may deadlock.
1470  */
1471 static void process_message(struct ceph_connection *con)
1472 {
1473         struct ceph_msg *msg;
1474
1475         msg = con->in_msg;
1476         con->in_msg = NULL;
1477
1478         /* if first message, set peer_name */
1479         if (con->peer_name.type == 0)
1480                 con->peer_name = msg->hdr.src.name;
1481
1482         con->in_seq++;
1483         mutex_unlock(&con->mutex);
1484
1485         dout("===== %p %llu from %s%lld %d=%s len %d+%d (%u %u %u) =====\n",
1486              msg, le64_to_cpu(msg->hdr.seq),
1487              ENTITY_NAME(msg->hdr.src.name),
1488              le16_to_cpu(msg->hdr.type),
1489              ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
1490              le32_to_cpu(msg->hdr.front_len),
1491              le32_to_cpu(msg->hdr.data_len),
1492              con->in_front_crc, con->in_middle_crc, con->in_data_crc);
1493         con->ops->dispatch(con, msg);
1494
1495         mutex_lock(&con->mutex);
1496         prepare_read_tag(con);
1497 }
1498
1499
1500 /*
1501  * Write something to the socket.  Called in a worker thread when the
1502  * socket appears to be writeable and we have something ready to send.
1503  */
1504 static int try_write(struct ceph_connection *con)
1505 {
1506         struct ceph_messenger *msgr = con->msgr;
1507         int ret = 1;
1508
1509         dout("try_write start %p state %lu nref %d\n", con, con->state,
1510              atomic_read(&con->nref));
1511
1512         mutex_lock(&con->mutex);
1513 more:
1514         dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes);
1515
1516         /* open the socket first? */
1517         if (con->sock == NULL) {
1518                 /*
1519                  * if we were STANDBY and are reconnecting _this_
1520                  * connection, bump connect_seq now.  Always bump
1521                  * global_seq.
1522                  */
1523                 if (test_and_clear_bit(STANDBY, &con->state))
1524                         con->connect_seq++;
1525
1526                 prepare_write_banner(msgr, con);
1527                 prepare_write_connect(msgr, con, 1);
1528                 prepare_read_banner(con);
1529                 set_bit(CONNECTING, &con->state);
1530                 clear_bit(NEGOTIATING, &con->state);
1531
1532                 BUG_ON(con->in_msg);
1533                 con->in_tag = CEPH_MSGR_TAG_READY;
1534                 dout("try_write initiating connect on %p new state %lu\n",
1535                      con, con->state);
1536                 con->sock = ceph_tcp_connect(con);
1537                 if (IS_ERR(con->sock)) {
1538                         con->sock = NULL;
1539                         con->error_msg = "connect error";
1540                         ret = -1;
1541                         goto out;
1542                 }
1543         }
1544
1545 more_kvec:
1546         /* kvec data queued? */
1547         if (con->out_skip) {
1548                 ret = write_partial_skip(con);
1549                 if (ret <= 0)
1550                         goto done;
1551                 if (ret < 0) {
1552                         dout("try_write write_partial_skip err %d\n", ret);
1553                         goto done;
1554                 }
1555         }
1556         if (con->out_kvec_left) {
1557                 ret = write_partial_kvec(con);
1558                 if (ret <= 0)
1559                         goto done;
1560         }
1561
1562         /* msg pages? */
1563         if (con->out_msg) {
1564                 if (con->out_msg_done) {
1565                         ceph_msg_put(con->out_msg);
1566                         con->out_msg = NULL;   /* we're done with this one */
1567                         goto do_next;
1568                 }
1569
1570                 ret = write_partial_msg_pages(con);
1571                 if (ret == 1)
1572                         goto more_kvec;  /* we need to send the footer, too! */
1573                 if (ret == 0)
1574                         goto done;
1575                 if (ret < 0) {
1576                         dout("try_write write_partial_msg_pages err %d\n",
1577                              ret);
1578                         goto done;
1579                 }
1580         }
1581
1582 do_next:
1583         if (!test_bit(CONNECTING, &con->state)) {
1584                 /* is anything else pending? */
1585                 if (!list_empty(&con->out_queue)) {
1586                         prepare_write_message(con);
1587                         goto more;
1588                 }
1589                 if (con->in_seq > con->in_seq_acked) {
1590                         prepare_write_ack(con);
1591                         goto more;
1592                 }
1593                 if (test_and_clear_bit(KEEPALIVE_PENDING, &con->state)) {
1594                         prepare_write_keepalive(con);
1595                         goto more;
1596                 }
1597         }
1598
1599         /* Nothing to do! */
1600         clear_bit(WRITE_PENDING, &con->state);
1601         dout("try_write nothing else to write.\n");
1602 done:
1603         ret = 0;
1604 out:
1605         mutex_unlock(&con->mutex);
1606         dout("try_write done on %p\n", con);
1607         return ret;
1608 }
1609
1610
1611
1612 /*
1613  * Read what we can from the socket.
1614  */
1615 static int try_read(struct ceph_connection *con)
1616 {
1617         struct ceph_messenger *msgr;
1618         int ret = -1;
1619
1620         if (!con->sock)
1621                 return 0;
1622
1623         if (test_bit(STANDBY, &con->state))
1624                 return 0;
1625
1626         dout("try_read start on %p\n", con);
1627         msgr = con->msgr;
1628
1629         mutex_lock(&con->mutex);
1630
1631 more:
1632         dout("try_read tag %d in_base_pos %d\n", (int)con->in_tag,
1633              con->in_base_pos);
1634         if (test_bit(CONNECTING, &con->state)) {
1635                 if (!test_bit(NEGOTIATING, &con->state)) {
1636                         dout("try_read connecting\n");
1637                         ret = read_partial_banner(con);
1638                         if (ret <= 0)
1639                                 goto done;
1640                         if (process_banner(con) < 0) {
1641                                 ret = -1;
1642                                 goto out;
1643                         }
1644                 }
1645                 ret = read_partial_connect(con);
1646                 if (ret <= 0)
1647                         goto done;
1648                 if (process_connect(con) < 0) {
1649                         ret = -1;
1650                         goto out;
1651                 }
1652                 goto more;
1653         }
1654
1655         if (con->in_base_pos < 0) {
1656                 /*
1657                  * skipping + discarding content.
1658                  *
1659                  * FIXME: there must be a better way to do this!
1660                  */
1661                 static char buf[1024];
1662                 int skip = min(1024, -con->in_base_pos);
1663                 dout("skipping %d / %d bytes\n", skip, -con->in_base_pos);
1664                 ret = ceph_tcp_recvmsg(con->sock, buf, skip);
1665                 if (ret <= 0)
1666                         goto done;
1667                 con->in_base_pos += ret;
1668                 if (con->in_base_pos)
1669                         goto more;
1670         }
1671         if (con->in_tag == CEPH_MSGR_TAG_READY) {
1672                 /*
1673                  * what's next?
1674                  */
1675                 ret = ceph_tcp_recvmsg(con->sock, &con->in_tag, 1);
1676                 if (ret <= 0)
1677                         goto done;
1678                 dout("try_read got tag %d\n", (int)con->in_tag);
1679                 switch (con->in_tag) {
1680                 case CEPH_MSGR_TAG_MSG:
1681                         prepare_read_message(con);
1682                         break;
1683                 case CEPH_MSGR_TAG_ACK:
1684                         prepare_read_ack(con);
1685                         break;
1686                 case CEPH_MSGR_TAG_CLOSE:
1687                         set_bit(CLOSED, &con->state);   /* fixme */
1688                         goto done;
1689                 default:
1690                         goto bad_tag;
1691                 }
1692         }
1693         if (con->in_tag == CEPH_MSGR_TAG_MSG) {
1694                 ret = read_partial_message(con);
1695                 if (ret <= 0) {
1696                         switch (ret) {
1697                         case -EBADMSG:
1698                                 con->error_msg = "bad crc";
1699                                 ret = -EIO;
1700                                 goto out;
1701                         case -EIO:
1702                                 con->error_msg = "io error";
1703                                 goto out;
1704                         default:
1705                                 goto done;
1706                         }
1707                 }
1708                 if (con->in_tag == CEPH_MSGR_TAG_READY)
1709                         goto more;
1710                 process_message(con);
1711                 goto more;
1712         }
1713         if (con->in_tag == CEPH_MSGR_TAG_ACK) {
1714                 ret = read_partial_ack(con);
1715                 if (ret <= 0)
1716                         goto done;
1717                 process_ack(con);
1718                 goto more;
1719         }
1720
1721 done:
1722         ret = 0;
1723 out:
1724         mutex_unlock(&con->mutex);
1725         dout("try_read done on %p\n", con);
1726         return ret;
1727
1728 bad_tag:
1729         pr_err("try_read bad con->in_tag = %d\n", (int)con->in_tag);
1730         con->error_msg = "protocol error, garbage tag";
1731         ret = -1;
1732         goto out;
1733 }
1734
1735
1736 /*
1737  * Atomically queue work on a connection.  Bump @con reference to
1738  * avoid races with connection teardown.
1739  *
1740  * There is some trickery going on with QUEUED and BUSY because we
1741  * only want a _single_ thread operating on each connection at any
1742  * point in time, but we want to use all available CPUs.
1743  *
1744  * The worker thread only proceeds if it can atomically set BUSY.  It
1745  * clears QUEUED and does it's thing.  When it thinks it's done, it
1746  * clears BUSY, then rechecks QUEUED.. if it's set again, it loops
1747  * (tries again to set BUSY).
1748  *
1749  * To queue work, we first set QUEUED, _then_ if BUSY isn't set, we
1750  * try to queue work.  If that fails (work is already queued, or BUSY)
1751  * we give up (work also already being done or is queued) but leave QUEUED
1752  * set so that the worker thread will loop if necessary.
1753  */
1754 static void queue_con(struct ceph_connection *con)
1755 {
1756         if (test_bit(DEAD, &con->state)) {
1757                 dout("queue_con %p ignoring: DEAD\n",
1758                      con);
1759                 return;
1760         }
1761
1762         if (!con->ops->get(con)) {
1763                 dout("queue_con %p ref count 0\n", con);
1764                 return;
1765         }
1766
1767         set_bit(QUEUED, &con->state);
1768         if (test_bit(BUSY, &con->state)) {
1769                 dout("queue_con %p - already BUSY\n", con);
1770                 con->ops->put(con);
1771         } else if (!queue_work(ceph_msgr_wq, &con->work.work)) {
1772                 dout("queue_con %p - already queued\n", con);
1773                 con->ops->put(con);
1774         } else {
1775                 dout("queue_con %p\n", con);
1776         }
1777 }
1778
1779 /*
1780  * Do some work on a connection.  Drop a connection ref when we're done.
1781  */
1782 static void con_work(struct work_struct *work)
1783 {
1784         struct ceph_connection *con = container_of(work, struct ceph_connection,
1785                                                    work.work);
1786         int backoff = 0;
1787
1788 more:
1789         if (test_and_set_bit(BUSY, &con->state) != 0) {
1790                 dout("con_work %p BUSY already set\n", con);
1791                 goto out;
1792         }
1793         dout("con_work %p start, clearing QUEUED\n", con);
1794         clear_bit(QUEUED, &con->state);
1795
1796         if (test_bit(CLOSED, &con->state)) { /* e.g. if we are replaced */
1797                 dout("con_work CLOSED\n");
1798                 con_close_socket(con);
1799                 goto done;
1800         }
1801         if (test_and_clear_bit(OPENING, &con->state)) {
1802                 /* reopen w/ new peer */
1803                 dout("con_work OPENING\n");
1804                 con_close_socket(con);
1805         }
1806
1807         if (test_and_clear_bit(SOCK_CLOSED, &con->state) ||
1808             try_read(con) < 0 ||
1809             try_write(con) < 0) {
1810                 backoff = 1;
1811                 ceph_fault(con);     /* error/fault path */
1812         }
1813
1814 done:
1815         clear_bit(BUSY, &con->state);
1816         dout("con->state=%lu\n", con->state);
1817         if (test_bit(QUEUED, &con->state)) {
1818                 if (!backoff || test_bit(OPENING, &con->state)) {
1819                         dout("con_work %p QUEUED reset, looping\n", con);
1820                         goto more;
1821                 }
1822                 dout("con_work %p QUEUED reset, but just faulted\n", con);
1823                 clear_bit(QUEUED, &con->state);
1824         }
1825         dout("con_work %p done\n", con);
1826
1827 out:
1828         con->ops->put(con);
1829 }
1830
1831
1832 /*
1833  * Generic error/fault handler.  A retry mechanism is used with
1834  * exponential backoff
1835  */
1836 static void ceph_fault(struct ceph_connection *con)
1837 {
1838         pr_err("%s%lld %s %s\n", ENTITY_NAME(con->peer_name),
1839                pr_addr(&con->peer_addr.in_addr), con->error_msg);
1840         dout("fault %p state %lu to peer %s\n",
1841              con, con->state, pr_addr(&con->peer_addr.in_addr));
1842
1843         if (test_bit(LOSSYTX, &con->state)) {
1844                 dout("fault on LOSSYTX channel\n");
1845                 goto out;
1846         }
1847
1848         mutex_lock(&con->mutex);
1849         if (test_bit(CLOSED, &con->state))
1850                 goto out_unlock;
1851
1852         con_close_socket(con);
1853
1854         if (con->in_msg) {
1855                 ceph_msg_put(con->in_msg);
1856                 con->in_msg = NULL;
1857         }
1858
1859         /* Requeue anything that hasn't been acked */
1860         list_splice_init(&con->out_sent, &con->out_queue);
1861
1862         /* If there are no messages in the queue, place the connection
1863          * in a STANDBY state (i.e., don't try to reconnect just yet). */
1864         if (list_empty(&con->out_queue) && !con->out_keepalive_pending) {
1865                 dout("fault setting STANDBY\n");
1866                 set_bit(STANDBY, &con->state);
1867         } else {
1868                 /* retry after a delay. */
1869                 if (con->delay == 0)
1870                         con->delay = BASE_DELAY_INTERVAL;
1871                 else if (con->delay < MAX_DELAY_INTERVAL)
1872                         con->delay *= 2;
1873                 dout("fault queueing %p delay %lu\n", con, con->delay);
1874                 con->ops->get(con);
1875                 if (queue_delayed_work(ceph_msgr_wq, &con->work,
1876                                        round_jiffies_relative(con->delay)) == 0)
1877                         con->ops->put(con);
1878         }
1879
1880 out_unlock:
1881         mutex_unlock(&con->mutex);
1882 out:
1883         /*
1884          * in case we faulted due to authentication, invalidate our
1885          * current tickets so that we can get new ones.
1886          */
1887         if (con->auth_retry && con->ops->invalidate_authorizer) {
1888                 dout("calling invalidate_authorizer()\n");
1889                 con->ops->invalidate_authorizer(con);
1890         }
1891
1892         if (con->ops->fault)
1893                 con->ops->fault(con);
1894 }
1895
1896
1897
1898 /*
1899  * create a new messenger instance
1900  */
1901 struct ceph_messenger *ceph_messenger_create(struct ceph_entity_addr *myaddr)
1902 {
1903         struct ceph_messenger *msgr;
1904
1905         msgr = kzalloc(sizeof(*msgr), GFP_KERNEL);
1906         if (msgr == NULL)
1907                 return ERR_PTR(-ENOMEM);
1908
1909         spin_lock_init(&msgr->global_seq_lock);
1910
1911         /* the zero page is needed if a request is "canceled" while the message
1912          * is being written over the socket */
1913         msgr->zero_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1914         if (!msgr->zero_page) {
1915                 kfree(msgr);
1916                 return ERR_PTR(-ENOMEM);
1917         }
1918         kmap(msgr->zero_page);
1919
1920         if (myaddr)
1921                 msgr->inst.addr = *myaddr;
1922
1923         /* select a random nonce */
1924         msgr->inst.addr.type = 0;
1925         get_random_bytes(&msgr->inst.addr.nonce, sizeof(msgr->inst.addr.nonce));
1926         encode_my_addr(msgr);
1927
1928         dout("messenger_create %p\n", msgr);
1929         return msgr;
1930 }
1931
1932 void ceph_messenger_destroy(struct ceph_messenger *msgr)
1933 {
1934         dout("destroy %p\n", msgr);
1935         kunmap(msgr->zero_page);
1936         __free_page(msgr->zero_page);
1937         kfree(msgr);
1938         dout("destroyed messenger %p\n", msgr);
1939 }
1940
1941 /*
1942  * Queue up an outgoing message on the given connection.
1943  */
1944 void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg)
1945 {
1946         if (test_bit(CLOSED, &con->state)) {
1947                 dout("con_send %p closed, dropping %p\n", con, msg);
1948                 ceph_msg_put(msg);
1949                 return;
1950         }
1951
1952         /* set src+dst */
1953         msg->hdr.src.name = con->msgr->inst.name;
1954         msg->hdr.src.addr = con->msgr->my_enc_addr;
1955         msg->hdr.orig_src = msg->hdr.src;
1956
1957         BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len));
1958
1959         /* queue */
1960         mutex_lock(&con->mutex);
1961         BUG_ON(!list_empty(&msg->list_head));
1962         list_add_tail(&msg->list_head, &con->out_queue);
1963         dout("----- %p to %s%lld %d=%s len %d+%d+%d -----\n", msg,
1964              ENTITY_NAME(con->peer_name), le16_to_cpu(msg->hdr.type),
1965              ceph_msg_type_name(le16_to_cpu(msg->hdr.type)),
1966              le32_to_cpu(msg->hdr.front_len),
1967              le32_to_cpu(msg->hdr.middle_len),
1968              le32_to_cpu(msg->hdr.data_len));
1969         mutex_unlock(&con->mutex);
1970
1971         /* if there wasn't anything waiting to send before, queue
1972          * new work */
1973         if (test_and_set_bit(WRITE_PENDING, &con->state) == 0)
1974                 queue_con(con);
1975 }
1976
1977 /*
1978  * Revoke a message that was previously queued for send
1979  */
1980 void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg)
1981 {
1982         mutex_lock(&con->mutex);
1983         if (!list_empty(&msg->list_head)) {
1984                 dout("con_revoke %p msg %p\n", con, msg);
1985                 list_del_init(&msg->list_head);
1986                 ceph_msg_put(msg);
1987                 msg->hdr.seq = 0;
1988                 if (con->out_msg == msg) {
1989                         ceph_msg_put(con->out_msg);
1990                         con->out_msg = NULL;
1991                 }
1992                 if (con->out_kvec_is_msg) {
1993                         con->out_skip = con->out_kvec_bytes;
1994                         con->out_kvec_is_msg = false;
1995                 }
1996         } else {
1997                 dout("con_revoke %p msg %p - not queued (sent?)\n", con, msg);
1998         }
1999         mutex_unlock(&con->mutex);
2000 }
2001
2002 /*
2003  * Revoke a message that we may be reading data into
2004  */
2005 void ceph_con_revoke_message(struct ceph_connection *con, struct ceph_msg *msg)
2006 {
2007         mutex_lock(&con->mutex);
2008         if (con->in_msg && con->in_msg == msg) {
2009                 unsigned front_len = le32_to_cpu(con->in_hdr.front_len);
2010                 unsigned middle_len = le32_to_cpu(con->in_hdr.middle_len);
2011                 unsigned data_len = le32_to_cpu(con->in_hdr.data_len);
2012
2013                 /* skip rest of message */
2014                 dout("con_revoke_pages %p msg %p revoked\n", con, msg);
2015                         con->in_base_pos = con->in_base_pos -
2016                                 sizeof(struct ceph_msg_header) -
2017                                 front_len -
2018                                 middle_len -
2019                                 data_len -
2020                                 sizeof(struct ceph_msg_footer);
2021                 ceph_msg_put(con->in_msg);
2022                 con->in_msg = NULL;
2023                 con->in_tag = CEPH_MSGR_TAG_READY;
2024         } else {
2025                 dout("con_revoke_pages %p msg %p pages %p no-op\n",
2026                      con, con->in_msg, msg);
2027         }
2028         mutex_unlock(&con->mutex);
2029 }
2030
2031 /*
2032  * Queue a keepalive byte to ensure the tcp connection is alive.
2033  */
2034 void ceph_con_keepalive(struct ceph_connection *con)
2035 {
2036         if (test_and_set_bit(KEEPALIVE_PENDING, &con->state) == 0 &&
2037             test_and_set_bit(WRITE_PENDING, &con->state) == 0)
2038                 queue_con(con);
2039 }
2040
2041
2042 /*
2043  * construct a new message with given type, size
2044  * the new msg has a ref count of 1.
2045  */
2046 struct ceph_msg *ceph_msg_new(int type, int front_len,
2047                               int page_len, int page_off, struct page **pages)
2048 {
2049         struct ceph_msg *m;
2050
2051         m = kmalloc(sizeof(*m), GFP_NOFS);
2052         if (m == NULL)
2053                 goto out;
2054         kref_init(&m->kref);
2055         INIT_LIST_HEAD(&m->list_head);
2056
2057         m->hdr.type = cpu_to_le16(type);
2058         m->hdr.front_len = cpu_to_le32(front_len);
2059         m->hdr.middle_len = 0;
2060         m->hdr.data_len = cpu_to_le32(page_len);
2061         m->hdr.data_off = cpu_to_le16(page_off);
2062         m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT);
2063         m->footer.front_crc = 0;
2064         m->footer.middle_crc = 0;
2065         m->footer.data_crc = 0;
2066         m->front_max = front_len;
2067         m->front_is_vmalloc = false;
2068         m->more_to_follow = false;
2069         m->pool = NULL;
2070
2071         /* front */
2072         if (front_len) {
2073                 if (front_len > PAGE_CACHE_SIZE) {
2074                         m->front.iov_base = __vmalloc(front_len, GFP_NOFS,
2075                                                       PAGE_KERNEL);
2076                         m->front_is_vmalloc = true;
2077                 } else {
2078                         m->front.iov_base = kmalloc(front_len, GFP_NOFS);
2079                 }
2080                 if (m->front.iov_base == NULL) {
2081                         pr_err("msg_new can't allocate %d bytes\n",
2082                              front_len);
2083                         goto out2;
2084                 }
2085         } else {
2086                 m->front.iov_base = NULL;
2087         }
2088         m->front.iov_len = front_len;
2089
2090         /* middle */
2091         m->middle = NULL;
2092
2093         /* data */
2094         m->nr_pages = calc_pages_for(page_off, page_len);
2095         m->pages = pages;
2096         m->pagelist = NULL;
2097
2098         dout("ceph_msg_new %p page %d~%d -> %d\n", m, page_off, page_len,
2099              m->nr_pages);
2100         return m;
2101
2102 out2:
2103         ceph_msg_put(m);
2104 out:
2105         pr_err("msg_new can't create type %d len %d\n", type, front_len);
2106         return ERR_PTR(-ENOMEM);
2107 }
2108
2109 /*
2110  * Allocate "middle" portion of a message, if it is needed and wasn't
2111  * allocated by alloc_msg.  This allows us to read a small fixed-size
2112  * per-type header in the front and then gracefully fail (i.e.,
2113  * propagate the error to the caller based on info in the front) when
2114  * the middle is too large.
2115  */
2116 static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg)
2117 {
2118         int type = le16_to_cpu(msg->hdr.type);
2119         int middle_len = le32_to_cpu(msg->hdr.middle_len);
2120
2121         dout("alloc_middle %p type %d %s middle_len %d\n", msg, type,
2122              ceph_msg_type_name(type), middle_len);
2123         BUG_ON(!middle_len);
2124         BUG_ON(msg->middle);
2125
2126         msg->middle = ceph_buffer_new(middle_len, GFP_NOFS);
2127         if (!msg->middle)
2128                 return -ENOMEM;
2129         return 0;
2130 }
2131
2132 /*
2133  * Generic message allocator, for incoming messages.
2134  */
2135 static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
2136                                 struct ceph_msg_header *hdr,
2137                                 int *skip)
2138 {
2139         int type = le16_to_cpu(hdr->type);
2140         int front_len = le32_to_cpu(hdr->front_len);
2141         int middle_len = le32_to_cpu(hdr->middle_len);
2142         struct ceph_msg *msg = NULL;
2143         int ret;
2144
2145         if (con->ops->alloc_msg) {
2146                 mutex_unlock(&con->mutex);
2147                 msg = con->ops->alloc_msg(con, hdr, skip);
2148                 mutex_lock(&con->mutex);
2149                 if (IS_ERR(msg))
2150                         return msg;
2151
2152                 if (*skip)
2153                         return NULL;
2154         }
2155         if (!msg) {
2156                 *skip = 0;
2157                 msg = ceph_msg_new(type, front_len, 0, 0, NULL);
2158                 if (!msg) {
2159                         pr_err("unable to allocate msg type %d len %d\n",
2160                                type, front_len);
2161                         return ERR_PTR(-ENOMEM);
2162                 }
2163         }
2164         memcpy(&msg->hdr, &con->in_hdr, sizeof(con->in_hdr));
2165
2166         if (middle_len) {
2167                 ret = ceph_alloc_middle(con, msg);
2168
2169                 if (ret < 0) {
2170                         ceph_msg_put(msg);
2171                         return msg;
2172                 }
2173         }
2174
2175         return msg;
2176 }
2177
2178
2179 /*
2180  * Free a generically kmalloc'd message.
2181  */
2182 void ceph_msg_kfree(struct ceph_msg *m)
2183 {
2184         dout("msg_kfree %p\n", m);
2185         if (m->front_is_vmalloc)
2186                 vfree(m->front.iov_base);
2187         else
2188                 kfree(m->front.iov_base);
2189         kfree(m);
2190 }
2191
2192 /*
2193  * Drop a msg ref.  Destroy as needed.
2194  */
2195 void ceph_msg_last_put(struct kref *kref)
2196 {
2197         struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
2198
2199         dout("ceph_msg_put last one on %p\n", m);
2200         WARN_ON(!list_empty(&m->list_head));
2201
2202         /* drop middle, data, if any */
2203         if (m->middle) {
2204                 ceph_buffer_put(m->middle);
2205                 m->middle = NULL;
2206         }
2207         m->nr_pages = 0;
2208         m->pages = NULL;
2209
2210         if (m->pagelist) {
2211                 ceph_pagelist_release(m->pagelist);
2212                 kfree(m->pagelist);
2213                 m->pagelist = NULL;
2214         }
2215
2216         if (m->pool)
2217                 ceph_msgpool_put(m->pool, m);
2218         else
2219                 ceph_msg_kfree(m);
2220 }
2221
2222 void ceph_msg_dump(struct ceph_msg *msg)
2223 {
2224         pr_debug("msg_dump %p (front_max %d nr_pages %d)\n", msg,
2225                  msg->front_max, msg->nr_pages);
2226         print_hex_dump(KERN_DEBUG, "header: ",
2227                        DUMP_PREFIX_OFFSET, 16, 1,
2228                        &msg->hdr, sizeof(msg->hdr), true);
2229         print_hex_dump(KERN_DEBUG, " front: ",
2230                        DUMP_PREFIX_OFFSET, 16, 1,
2231                        msg->front.iov_base, msg->front.iov_len, true);
2232         if (msg->middle)
2233                 print_hex_dump(KERN_DEBUG, "middle: ",
2234                                DUMP_PREFIX_OFFSET, 16, 1,
2235                                msg->middle->vec.iov_base,
2236                                msg->middle->vec.iov_len, true);
2237         print_hex_dump(KERN_DEBUG, "footer: ",
2238                        DUMP_PREFIX_OFFSET, 16, 1,
2239                        &msg->footer, sizeof(msg->footer), true);
2240 }