net/ceph/messenger_v1.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/ceph/ceph_debug.h>
   3
   4 #include <linux/bvec.h>
   5 #include <linux/crc32c.h>
   6 #include <linux/net.h>
   7 #include <linux/socket.h>
   8 #include <net/sock.h>
   9
  10 #include <linux/ceph/ceph_features.h>
  11 #include <linux/ceph/decode.h>
  12 #include <linux/ceph/libceph.h>
  13 #include <linux/ceph/messenger.h>
  14
  15 /* static tag bytes (protocol control messages) */
  16 static char tag_msg = CEPH_MSGR_TAG_MSG;
  17 static char tag_ack = CEPH_MSGR_TAG_ACK;
  18 static char tag_keepalive = CEPH_MSGR_TAG_KEEPALIVE;
  19 static char tag_keepalive2 = CEPH_MSGR_TAG_KEEPALIVE2;
  20
  21 /*
  22  * If @buf is NULL, discard up to @len bytes.
  23  */
  24 static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len)
  25 {
  26         struct kvec iov = {buf, len};
  27         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
  28         int r;
  29
  30         if (!buf)
  31                 msg.msg_flags |= MSG_TRUNC;
  32
  33         iov_iter_kvec(&msg.msg_iter, ITER_DEST, &iov, 1, len);
  34         r = sock_recvmsg(sock, &msg, msg.msg_flags);
  35         if (r == -EAGAIN)
  36                 r = 0;
  37         return r;
  38 }
  39
  40 static int ceph_tcp_recvpage(struct socket *sock, struct page *page,
  41                      int page_offset, size_t length)
  42 {
  43         struct bio_vec bvec;
  44         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
  45         int r;
  46
  47         BUG_ON(page_offset + length > PAGE_SIZE);
  48         bvec_set_page(&bvec, page, length, page_offset);
  49         iov_iter_bvec(&msg.msg_iter, ITER_DEST, &bvec, 1, length);
  50         r = sock_recvmsg(sock, &msg, msg.msg_flags);
  51         if (r == -EAGAIN)
  52                 r = 0;
  53         return r;
  54 }
  55
  56 /*
  57  * write something.  @more is true if caller will be sending more data
  58  * shortly.
  59  */
  60 static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov,
  61                             size_t kvlen, size_t len, bool more)
  62 {
  63         struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL };
  64         int r;
  65
  66         if (more)
  67                 msg.msg_flags |= MSG_MORE;
  68         else
  69                 msg.msg_flags |= MSG_EOR;  /* superfluous, but what the hell */
  70
  71         r = kernel_sendmsg(sock, &msg, iov, kvlen, len);
  72         if (r == -EAGAIN)
  73                 r = 0;
  74         return r;
  75 }
  76
  77 /*
  78  * @more: MSG_MORE or 0.
  79  */
  80 static int ceph_tcp_sendpage(struct socket *sock, struct page *page,
  81                              int offset, size_t size, int more)
  82 {
  83         struct msghdr msg = {
  84                 .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL | more,
  85         };
  86         struct bio_vec bvec;
  87         int ret;
  88
  89         /*
  90          * MSG_SPLICE_PAGES cannot properly handle pages with page_count == 0,
  91          * we need to fall back to sendmsg if that's the case.
  92          *
  93          * Same goes for slab pages: skb_can_coalesce() allows
  94          * coalescing neighboring slab objects into a single frag which
  95          * triggers one of hardened usercopy checks.
  96          */
  97         if (sendpage_ok(page))
  98                 msg.msg_flags |= MSG_SPLICE_PAGES;
  99
 100         bvec_set_page(&bvec, page, size, offset);
 101         iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
 102
 103         ret = sock_sendmsg(sock, &msg);
 104         if (ret == -EAGAIN)
 105                 ret = 0;
 106
 107         return ret;
 108 }
 109
 110 static void con_out_kvec_reset(struct ceph_connection *con)
 111 {
 112         BUG_ON(con->v1.out_skip);
 113
 114         con->v1.out_kvec_left = 0;
 115         con->v1.out_kvec_bytes = 0;
 116         con->v1.out_kvec_cur = &con->v1.out_kvec[0];
 117 }
 118
 119 static void con_out_kvec_add(struct ceph_connection *con,
 120                                 size_t size, void *data)
 121 {
 122         int index = con->v1.out_kvec_left;
 123
 124         BUG_ON(con->v1.out_skip);
 125         BUG_ON(index >= ARRAY_SIZE(con->v1.out_kvec));
 126
 127         con->v1.out_kvec[index].iov_len = size;
 128         con->v1.out_kvec[index].iov_base = data;
 129         con->v1.out_kvec_left++;
 130         con->v1.out_kvec_bytes += size;
 131 }
 132
 133 /*
 134  * Chop off a kvec from the end.  Return residual number of bytes for
 135  * that kvec, i.e. how many bytes would have been written if the kvec
 136  * hadn't been nuked.
 137  */
 138 static int con_out_kvec_skip(struct ceph_connection *con)
 139 {
 140         int skip = 0;
 141
 142         if (con->v1.out_kvec_bytes > 0) {
 143                 skip = con->v1.out_kvec_cur[con->v1.out_kvec_left - 1].iov_len;
 144                 BUG_ON(con->v1.out_kvec_bytes < skip);
 145                 BUG_ON(!con->v1.out_kvec_left);
 146                 con->v1.out_kvec_bytes -= skip;
 147                 con->v1.out_kvec_left--;
 148         }
 149
 150         return skip;
 151 }
 152
 153 static size_t sizeof_footer(struct ceph_connection *con)
 154 {
 155         return (con->peer_features & CEPH_FEATURE_MSG_AUTH) ?
 156             sizeof(struct ceph_msg_footer) :
 157             sizeof(struct ceph_msg_footer_old);
 158 }
 159
 160 static void prepare_message_data(struct ceph_msg *msg, u32 data_len)
 161 {
 162         /* Initialize data cursor */
 163
 164         ceph_msg_data_cursor_init(&msg->cursor, msg, data_len);
 165 }
 166
 167 /*
 168  * Prepare footer for currently outgoing message, and finish things
 169  * off.  Assumes out_kvec* are already valid.. we just add on to the end.
 170  */
 171 static void prepare_write_message_footer(struct ceph_connection *con)
 172 {
 173         struct ceph_msg *m = con->out_msg;
 174
 175         m->footer.flags |= CEPH_MSG_FOOTER_COMPLETE;
 176
 177         dout("prepare_write_message_footer %p\n", con);
 178         con_out_kvec_add(con, sizeof_footer(con), &m->footer);
 179         if (con->peer_features & CEPH_FEATURE_MSG_AUTH) {
 180                 if (con->ops->sign_message)
 181                         con->ops->sign_message(m);
 182                 else
 183                         m->footer.sig = 0;
 184         } else {
 185                 m->old_footer.flags = m->footer.flags;
 186         }
 187         con->v1.out_more = m->more_to_follow;
 188         con->v1.out_msg_done = true;
 189 }
 190
 191 /*
 192  * Prepare headers for the next outgoing message.
 193  */
 194 static void prepare_write_message(struct ceph_connection *con)
 195 {
 196         struct ceph_msg *m;
 197         u32 crc;
 198
 199         con_out_kvec_reset(con);
 200         con->v1.out_msg_done = false;
 201
 202         /* Sneak an ack in there first?  If we can get it into the same
 203          * TCP packet that's a good thing. */
 204         if (con->in_seq > con->in_seq_acked) {
 205                 con->in_seq_acked = con->in_seq;
 206                 con_out_kvec_add(con, sizeof (tag_ack), &tag_ack);
 207                 con->v1.out_temp_ack = cpu_to_le64(con->in_seq_acked);
 208                 con_out_kvec_add(con, sizeof(con->v1.out_temp_ack),
 209                         &con->v1.out_temp_ack);
 210         }
 211
 212         ceph_con_get_out_msg(con);
 213         m = con->out_msg;
 214
 215         dout("prepare_write_message %p seq %lld type %d len %d+%d+%zd\n",
 216              m, con->out_seq, le16_to_cpu(m->hdr.type),
 217              le32_to_cpu(m->hdr.front_len), le32_to_cpu(m->hdr.middle_len),
 218              m->data_length);
 219         WARN_ON(m->front.iov_len != le32_to_cpu(m->hdr.front_len));
 220         WARN_ON(m->data_length != le32_to_cpu(m->hdr.data_len));
 221
 222         /* tag + hdr + front + middle */
 223         con_out_kvec_add(con, sizeof (tag_msg), &tag_msg);
 224         con_out_kvec_add(con, sizeof(con->v1.out_hdr), &con->v1.out_hdr);
 225         con_out_kvec_add(con, m->front.iov_len, m->front.iov_base);
 226
 227         if (m->middle)
 228                 con_out_kvec_add(con, m->middle->vec.iov_len,
 229                         m->middle->vec.iov_base);
 230
 231         /* fill in hdr crc and finalize hdr */
 232         crc = crc32c(0, &m->hdr, offsetof(struct ceph_msg_header, crc));
 233         con->out_msg->hdr.crc = cpu_to_le32(crc);
 234         memcpy(&con->v1.out_hdr, &con->out_msg->hdr, sizeof(con->v1.out_hdr));
 235
 236         /* fill in front and middle crc, footer */
 237         crc = crc32c(0, m->front.iov_base, m->front.iov_len);
 238         con->out_msg->footer.front_crc = cpu_to_le32(crc);
 239         if (m->middle) {
 240                 crc = crc32c(0, m->middle->vec.iov_base,
 241                                 m->middle->vec.iov_len);
 242                 con->out_msg->footer.middle_crc = cpu_to_le32(crc);
 243         } else
 244                 con->out_msg->footer.middle_crc = 0;
 245         dout("%s front_crc %u middle_crc %u\n", __func__,
 246              le32_to_cpu(con->out_msg->footer.front_crc),
 247              le32_to_cpu(con->out_msg->footer.middle_crc));
 248         con->out_msg->footer.flags = 0;
 249
 250         /* is there a data payload? */
 251         con->out_msg->footer.data_crc = 0;
 252         if (m->data_length) {
 253                 prepare_message_data(con->out_msg, m->data_length);
 254                 con->v1.out_more = 1;  /* data + footer will follow */
 255         } else {
 256                 /* no, queue up footer too and be done */
 257                 prepare_write_message_footer(con);
 258         }
 259
 260         ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
 261 }
 262
 263 /*
 264  * Prepare an ack.
 265  */
 266 static void prepare_write_ack(struct ceph_connection *con)
 267 {
 268         dout("prepare_write_ack %p %llu -> %llu\n", con,
 269              con->in_seq_acked, con->in_seq);
 270         con->in_seq_acked = con->in_seq;
 271
 272         con_out_kvec_reset(con);
 273
 274         con_out_kvec_add(con, sizeof (tag_ack), &tag_ack);
 275
 276         con->v1.out_temp_ack = cpu_to_le64(con->in_seq_acked);
 277         con_out_kvec_add(con, sizeof(con->v1.out_temp_ack),
 278                          &con->v1.out_temp_ack);
 279
 280         con->v1.out_more = 1;  /* more will follow.. eventually.. */
 281         ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
 282 }
 283
 284 /*
 285  * Prepare to share the seq during handshake
 286  */
 287 static void prepare_write_seq(struct ceph_connection *con)
 288 {
 289         dout("prepare_write_seq %p %llu -> %llu\n", con,
 290              con->in_seq_acked, con->in_seq);
 291         con->in_seq_acked = con->in_seq;
 292
 293         con_out_kvec_reset(con);
 294
 295         con->v1.out_temp_ack = cpu_to_le64(con->in_seq_acked);
 296         con_out_kvec_add(con, sizeof(con->v1.out_temp_ack),
 297                          &con->v1.out_temp_ack);
 298
 299         ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
 300 }
 301
 302 /*
 303  * Prepare to write keepalive byte.
 304  */
 305 static void prepare_write_keepalive(struct ceph_connection *con)
 306 {
 307         dout("prepare_write_keepalive %p\n", con);
 308         con_out_kvec_reset(con);
 309         if (con->peer_features & CEPH_FEATURE_MSGR_KEEPALIVE2) {
 310                 struct timespec64 now;
 311
 312                 ktime_get_real_ts64(&now);
 313                 con_out_kvec_add(con, sizeof(tag_keepalive2), &tag_keepalive2);
 314                 ceph_encode_timespec64(&con->v1.out_temp_keepalive2, &now);
 315                 con_out_kvec_add(con, sizeof(con->v1.out_temp_keepalive2),
 316                                  &con->v1.out_temp_keepalive2);
 317         } else {
 318                 con_out_kvec_add(con, sizeof(tag_keepalive), &tag_keepalive);
 319         }
 320         ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
 321 }
 322
 323 /*
 324  * Connection negotiation.
 325  */
 326
 327 static int get_connect_authorizer(struct ceph_connection *con)
 328 {
 329         struct ceph_auth_handshake *auth;
 330         int auth_proto;
 331
 332         if (!con->ops->get_authorizer) {
 333                 con->v1.auth = NULL;
 334                 con->v1.out_connect.authorizer_protocol = CEPH_AUTH_UNKNOWN;
 335                 con->v1.out_connect.authorizer_len = 0;
 336                 return 0;
 337         }
 338
 339         auth = con->ops->get_authorizer(con, &auth_proto, con->v1.auth_retry);
 340         if (IS_ERR(auth))
 341                 return PTR_ERR(auth);
 342
 343         con->v1.auth = auth;
 344         con->v1.out_connect.authorizer_protocol = cpu_to_le32(auth_proto);
 345         con->v1.out_connect.authorizer_len =
 346                 cpu_to_le32(auth->authorizer_buf_len);
 347         return 0;
 348 }
 349
 350 /*
 351  * We connected to a peer and are saying hello.
 352  */
 353 static void prepare_write_banner(struct ceph_connection *con)
 354 {
 355         con_out_kvec_add(con, strlen(CEPH_BANNER), CEPH_BANNER);
 356         con_out_kvec_add(con, sizeof (con->msgr->my_enc_addr),
 357                                         &con->msgr->my_enc_addr);
 358
 359         con->v1.out_more = 0;
 360         ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
 361 }
 362
 363 static void __prepare_write_connect(struct ceph_connection *con)
 364 {
 365         con_out_kvec_add(con, sizeof(con->v1.out_connect),
 366                          &con->v1.out_connect);
 367         if (con->v1.auth)
 368                 con_out_kvec_add(con, con->v1.auth->authorizer_buf_len,
 369                                  con->v1.auth->authorizer_buf);
 370
 371         con->v1.out_more = 0;
 372         ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
 373 }
 374
 375 static int prepare_write_connect(struct ceph_connection *con)
 376 {
 377         unsigned int global_seq = ceph_get_global_seq(con->msgr, 0);
 378         int proto;
 379         int ret;
 380
 381         switch (con->peer_name.type) {
 382         case CEPH_ENTITY_TYPE_MON:
 383                 proto = CEPH_MONC_PROTOCOL;
 384                 break;
 385         case CEPH_ENTITY_TYPE_OSD:
 386                 proto = CEPH_OSDC_PROTOCOL;
 387                 break;
 388         case CEPH_ENTITY_TYPE_MDS:
 389                 proto = CEPH_MDSC_PROTOCOL;
 390                 break;
 391         default:
 392                 BUG();
 393         }
 394
 395         dout("prepare_write_connect %p cseq=%d gseq=%d proto=%d\n", con,
 396              con->v1.connect_seq, global_seq, proto);
 397
 398         con->v1.out_connect.features =
 399                 cpu_to_le64(from_msgr(con->msgr)->supported_features);
 400         con->v1.out_connect.host_type = cpu_to_le32(CEPH_ENTITY_TYPE_CLIENT);
 401         con->v1.out_connect.connect_seq = cpu_to_le32(con->v1.connect_seq);
 402         con->v1.out_connect.global_seq = cpu_to_le32(global_seq);
 403         con->v1.out_connect.protocol_version = cpu_to_le32(proto);
 404         con->v1.out_connect.flags = 0;
 405
 406         ret = get_connect_authorizer(con);
 407         if (ret)
 408                 return ret;
 409
 410         __prepare_write_connect(con);
 411         return 0;
 412 }
 413
 414 /*
 415  * write as much of pending kvecs to the socket as we can.
 416  *  1 -> done
 417  *  0 -> socket full, but more to do
 418  * <0 -> error
 419  */
 420 static int write_partial_kvec(struct ceph_connection *con)
 421 {
 422         int ret;
 423
 424         dout("write_partial_kvec %p %d left\n", con, con->v1.out_kvec_bytes);
 425         while (con->v1.out_kvec_bytes > 0) {
 426                 ret = ceph_tcp_sendmsg(con->sock, con->v1.out_kvec_cur,
 427                                        con->v1.out_kvec_left,
 428                                        con->v1.out_kvec_bytes,
 429                                        con->v1.out_more);
 430                 if (ret <= 0)
 431                         goto out;
 432                 con->v1.out_kvec_bytes -= ret;
 433                 if (!con->v1.out_kvec_bytes)
 434                         break;            /* done */
 435
 436                 /* account for full iov entries consumed */
 437                 while (ret >= con->v1.out_kvec_cur->iov_len) {
 438                         BUG_ON(!con->v1.out_kvec_left);
 439                         ret -= con->v1.out_kvec_cur->iov_len;
 440                         con->v1.out_kvec_cur++;
 441                         con->v1.out_kvec_left--;
 442                 }
 443                 /* and for a partially-consumed entry */
 444                 if (ret) {
 445                         con->v1.out_kvec_cur->iov_len -= ret;
 446                         con->v1.out_kvec_cur->iov_base += ret;
 447                 }
 448         }
 449         con->v1.out_kvec_left = 0;
 450         ret = 1;
 451 out:
 452         dout("write_partial_kvec %p %d left in %d kvecs ret = %d\n", con,
 453              con->v1.out_kvec_bytes, con->v1.out_kvec_left, ret);
 454         return ret;  /* done! */
 455 }
 456
 457 /*
 458  * Write as much message data payload as we can.  If we finish, queue
 459  * up the footer.
 460  *  1 -> done, footer is now queued in out_kvec[].
 461  *  0 -> socket full, but more to do
 462  * <0 -> error
 463  */
 464 static int write_partial_message_data(struct ceph_connection *con)
 465 {
 466         struct ceph_msg *msg = con->out_msg;
 467         struct ceph_msg_data_cursor *cursor = &msg->cursor;
 468         bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC);
 469         u32 crc;
 470
 471         dout("%s %p msg %p\n", __func__, con, msg);
 472
 473         if (!msg->num_data_items)
 474                 return -EINVAL;
 475
 476         /*
 477          * Iterate through each page that contains data to be
 478          * written, and send as much as possible for each.
 479          *
 480          * If we are calculating the data crc (the default), we will
 481          * need to map the page.  If we have no pages, they have
 482          * been revoked, so use the zero page.
 483          */
 484         crc = do_datacrc ? le32_to_cpu(msg->footer.data_crc) : 0;
 485         while (cursor->total_resid) {
 486                 struct page *page;
 487                 size_t page_offset;
 488                 size_t length;
 489                 int ret;
 490
 491                 if (!cursor->resid) {
 492                         ceph_msg_data_advance(cursor, 0);
 493                         continue;
 494                 }
 495
 496                 page = ceph_msg_data_next(cursor, &page_offset, &length);
 497                 ret = ceph_tcp_sendpage(con->sock, page, page_offset, length,
 498                                         MSG_MORE);
 499                 if (ret <= 0) {
 500                         if (do_datacrc)
 501                                 msg->footer.data_crc = cpu_to_le32(crc);
 502
 503                         return ret;
 504                 }
 505                 if (do_datacrc && cursor->need_crc)
 506                         crc = ceph_crc32c_page(crc, page, page_offset, length);
 507                 ceph_msg_data_advance(cursor, (size_t)ret);
 508         }
 509
 510         dout("%s %p msg %p done\n", __func__, con, msg);
 511
 512         /* prepare and queue up footer, too */
 513         if (do_datacrc)
 514                 msg->footer.data_crc = cpu_to_le32(crc);
 515         else
 516                 msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
 517         con_out_kvec_reset(con);
 518         prepare_write_message_footer(con);
 519
 520         return 1;       /* must return > 0 to indicate success */
 521 }
 522
 523 /*
 524  * write some zeros
 525  */
 526 static int write_partial_skip(struct ceph_connection *con)
 527 {
 528         int ret;
 529
 530         dout("%s %p %d left\n", __func__, con, con->v1.out_skip);
 531         while (con->v1.out_skip > 0) {
 532                 size_t size = min(con->v1.out_skip, (int)PAGE_SIZE);
 533
 534                 ret = ceph_tcp_sendpage(con->sock, ceph_zero_page, 0, size,
 535                                         MSG_MORE);
 536                 if (ret <= 0)
 537                         goto out;
 538                 con->v1.out_skip -= ret;
 539         }
 540         ret = 1;
 541 out:
 542         return ret;
 543 }
 544
 545 /*
 546  * Prepare to read connection handshake, or an ack.
 547  */
 548 static void prepare_read_banner(struct ceph_connection *con)
 549 {
 550         dout("prepare_read_banner %p\n", con);
 551         con->v1.in_base_pos = 0;
 552 }
 553
 554 static void prepare_read_connect(struct ceph_connection *con)
 555 {
 556         dout("prepare_read_connect %p\n", con);
 557         con->v1.in_base_pos = 0;
 558 }
 559
 560 static void prepare_read_ack(struct ceph_connection *con)
 561 {
 562         dout("prepare_read_ack %p\n", con);
 563         con->v1.in_base_pos = 0;
 564 }
 565
 566 static void prepare_read_seq(struct ceph_connection *con)
 567 {
 568         dout("prepare_read_seq %p\n", con);
 569         con->v1.in_base_pos = 0;
 570         con->v1.in_tag = CEPH_MSGR_TAG_SEQ;
 571 }
 572
 573 static void prepare_read_tag(struct ceph_connection *con)
 574 {
 575         dout("prepare_read_tag %p\n", con);
 576         con->v1.in_base_pos = 0;
 577         con->v1.in_tag = CEPH_MSGR_TAG_READY;
 578 }
 579
 580 static void prepare_read_keepalive_ack(struct ceph_connection *con)
 581 {
 582         dout("prepare_read_keepalive_ack %p\n", con);
 583         con->v1.in_base_pos = 0;
 584 }
 585
 586 /*
 587  * Prepare to read a message.
 588  */
 589 static int prepare_read_message(struct ceph_connection *con)
 590 {
 591         dout("prepare_read_message %p\n", con);
 592         BUG_ON(con->in_msg != NULL);
 593         con->v1.in_base_pos = 0;
 594         con->in_front_crc = con->in_middle_crc = con->in_data_crc = 0;
 595         return 0;
 596 }
 597
 598 static int read_partial(struct ceph_connection *con,
 599                         int end, int size, void *object)
 600 {
 601         while (con->v1.in_base_pos < end) {
 602                 int left = end - con->v1.in_base_pos;
 603                 int have = size - left;
 604                 int ret = ceph_tcp_recvmsg(con->sock, object + have, left);
 605                 if (ret <= 0)
 606                         return ret;
 607                 con->v1.in_base_pos += ret;
 608         }
 609         return 1;
 610 }
 611
 612 /*
 613  * Read all or part of the connect-side handshake on a new connection
 614  */
 615 static int read_partial_banner(struct ceph_connection *con)
 616 {
 617         int size;
 618         int end;
 619         int ret;
 620
 621         dout("read_partial_banner %p at %d\n", con, con->v1.in_base_pos);
 622
 623         /* peer's banner */
 624         size = strlen(CEPH_BANNER);
 625         end = size;
 626         ret = read_partial(con, end, size, con->v1.in_banner);
 627         if (ret <= 0)
 628                 goto out;
 629
 630         size = sizeof(con->v1.actual_peer_addr);
 631         end += size;
 632         ret = read_partial(con, end, size, &con->v1.actual_peer_addr);
 633         if (ret <= 0)
 634                 goto out;
 635         ceph_decode_banner_addr(&con->v1.actual_peer_addr);
 636
 637         size = sizeof(con->v1.peer_addr_for_me);
 638         end += size;
 639         ret = read_partial(con, end, size, &con->v1.peer_addr_for_me);
 640         if (ret <= 0)
 641                 goto out;
 642         ceph_decode_banner_addr(&con->v1.peer_addr_for_me);
 643
 644 out:
 645         return ret;
 646 }
 647
 648 static int read_partial_connect(struct ceph_connection *con)
 649 {
 650         int size;
 651         int end;
 652         int ret;
 653
 654         dout("read_partial_connect %p at %d\n", con, con->v1.in_base_pos);
 655
 656         size = sizeof(con->v1.in_reply);
 657         end = size;
 658         ret = read_partial(con, end, size, &con->v1.in_reply);
 659         if (ret <= 0)
 660                 goto out;
 661
 662         if (con->v1.auth) {
 663                 size = le32_to_cpu(con->v1.in_reply.authorizer_len);
 664                 if (size > con->v1.auth->authorizer_reply_buf_len) {
 665                         pr_err("authorizer reply too big: %d > %zu\n", size,
 666                                con->v1.auth->authorizer_reply_buf_len);
 667                         ret = -EINVAL;
 668                         goto out;
 669                 }
 670
 671                 end += size;
 672                 ret = read_partial(con, end, size,
 673                                    con->v1.auth->authorizer_reply_buf);
 674                 if (ret <= 0)
 675                         goto out;
 676         }
 677
 678         dout("read_partial_connect %p tag %d, con_seq = %u, g_seq = %u\n",
 679              con, con->v1.in_reply.tag,
 680              le32_to_cpu(con->v1.in_reply.connect_seq),
 681              le32_to_cpu(con->v1.in_reply.global_seq));
 682 out:
 683         return ret;
 684 }
 685
 686 /*
 687  * Verify the hello banner looks okay.
 688  */
 689 static int verify_hello(struct ceph_connection *con)
 690 {
 691         if (memcmp(con->v1.in_banner, CEPH_BANNER, strlen(CEPH_BANNER))) {
 692                 pr_err("connect to %s got bad banner\n",
 693                        ceph_pr_addr(&con->peer_addr));
 694                 con->error_msg = "protocol error, bad banner";
 695                 return -1;
 696         }
 697         return 0;
 698 }
 699
 700 static int process_banner(struct ceph_connection *con)
 701 {
 702         struct ceph_entity_addr *my_addr = &con->msgr->inst.addr;
 703
 704         dout("process_banner on %p\n", con);
 705
 706         if (verify_hello(con) < 0)
 707                 return -1;
 708
 709         /*
 710          * Make sure the other end is who we wanted.  note that the other
 711          * end may not yet know their ip address, so if it's 0.0.0.0, give
 712          * them the benefit of the doubt.
 713          */
 714         if (memcmp(&con->peer_addr, &con->v1.actual_peer_addr,
 715                    sizeof(con->peer_addr)) != 0 &&
 716             !(ceph_addr_is_blank(&con->v1.actual_peer_addr) &&
 717               con->v1.actual_peer_addr.nonce == con->peer_addr.nonce)) {
 718                 pr_warn("wrong peer, want %s/%u, got %s/%u\n",
 719                         ceph_pr_addr(&con->peer_addr),
 720                         le32_to_cpu(con->peer_addr.nonce),
 721                         ceph_pr_addr(&con->v1.actual_peer_addr),
 722                         le32_to_cpu(con->v1.actual_peer_addr.nonce));
 723                 con->error_msg = "wrong peer at address";
 724                 return -1;
 725         }
 726
 727         /*
 728          * did we learn our address?
 729          */
 730         if (ceph_addr_is_blank(my_addr)) {
 731                 memcpy(&my_addr->in_addr,
 732                        &con->v1.peer_addr_for_me.in_addr,
 733                        sizeof(con->v1.peer_addr_for_me.in_addr));
 734                 ceph_addr_set_port(my_addr, 0);
 735                 ceph_encode_my_addr(con->msgr);
 736                 dout("process_banner learned my addr is %s\n",
 737                      ceph_pr_addr(my_addr));
 738         }
 739
 740         return 0;
 741 }
 742
 743 static int process_connect(struct ceph_connection *con)
 744 {
 745         u64 sup_feat = from_msgr(con->msgr)->supported_features;
 746         u64 req_feat = from_msgr(con->msgr)->required_features;
 747         u64 server_feat = le64_to_cpu(con->v1.in_reply.features);
 748         int ret;
 749
 750         dout("process_connect on %p tag %d\n", con, con->v1.in_tag);
 751
 752         if (con->v1.auth) {
 753                 int len = le32_to_cpu(con->v1.in_reply.authorizer_len);
 754
 755                 /*
 756                  * Any connection that defines ->get_authorizer()
 757                  * should also define ->add_authorizer_challenge() and
 758                  * ->verify_authorizer_reply().
 759                  *
 760                  * See get_connect_authorizer().
 761                  */
 762                 if (con->v1.in_reply.tag ==
 763                                 CEPH_MSGR_TAG_CHALLENGE_AUTHORIZER) {
 764                         ret = con->ops->add_authorizer_challenge(
 765                                 con, con->v1.auth->authorizer_reply_buf, len);
 766                         if (ret < 0)
 767                                 return ret;
 768
 769                         con_out_kvec_reset(con);
 770                         __prepare_write_connect(con);
 771                         prepare_read_connect(con);
 772                         return 0;
 773                 }
 774
 775                 if (len) {
 776                         ret = con->ops->verify_authorizer_reply(con);
 777                         if (ret < 0) {
 778                                 con->error_msg = "bad authorize reply";
 779                                 return ret;
 780                         }
 781                 }
 782         }
 783
 784         switch (con->v1.in_reply.tag) {
 785         case CEPH_MSGR_TAG_FEATURES:
 786                 pr_err("%s%lld %s feature set mismatch,"
 787                        " my %llx < server's %llx, missing %llx\n",
 788                        ENTITY_NAME(con->peer_name),
 789                        ceph_pr_addr(&con->peer_addr),
 790                        sup_feat, server_feat, server_feat & ~sup_feat);
 791                 con->error_msg = "missing required protocol features";
 792                 return -1;
 793
 794         case CEPH_MSGR_TAG_BADPROTOVER:
 795                 pr_err("%s%lld %s protocol version mismatch,"
 796                        " my %d != server's %d\n",
 797                        ENTITY_NAME(con->peer_name),
 798                        ceph_pr_addr(&con->peer_addr),
 799                        le32_to_cpu(con->v1.out_connect.protocol_version),
 800                        le32_to_cpu(con->v1.in_reply.protocol_version));
 801                 con->error_msg = "protocol version mismatch";
 802                 return -1;
 803
 804         case CEPH_MSGR_TAG_BADAUTHORIZER:
 805                 con->v1.auth_retry++;
 806                 dout("process_connect %p got BADAUTHORIZER attempt %d\n", con,
 807                      con->v1.auth_retry);
 808                 if (con->v1.auth_retry == 2) {
 809                         con->error_msg = "connect authorization failure";
 810                         return -1;
 811                 }
 812                 con_out_kvec_reset(con);
 813                 ret = prepare_write_connect(con);
 814                 if (ret < 0)
 815                         return ret;
 816                 prepare_read_connect(con);
 817                 break;
 818
 819         case CEPH_MSGR_TAG_RESETSESSION:
 820                 /*
 821                  * If we connected with a large connect_seq but the peer
 822                  * has no record of a session with us (no connection, or
 823                  * connect_seq == 0), they will send RESETSESION to indicate
 824                  * that they must have reset their session, and may have
 825                  * dropped messages.
 826                  */
 827                 dout("process_connect got RESET peer seq %u\n",
 828                      le32_to_cpu(con->v1.in_reply.connect_seq));
 829                 pr_info("%s%lld %s session reset\n",
 830                         ENTITY_NAME(con->peer_name),
 831                         ceph_pr_addr(&con->peer_addr));
 832                 ceph_con_reset_session(con);
 833                 con_out_kvec_reset(con);
 834                 ret = prepare_write_connect(con);
 835                 if (ret < 0)
 836                         return ret;
 837                 prepare_read_connect(con);
 838
 839                 /* Tell ceph about it. */
 840                 mutex_unlock(&con->mutex);
 841                 if (con->ops->peer_reset)
 842                         con->ops->peer_reset(con);
 843                 mutex_lock(&con->mutex);
 844                 if (con->state != CEPH_CON_S_V1_CONNECT_MSG)
 845                         return -EAGAIN;
 846                 break;
 847
 848         case CEPH_MSGR_TAG_RETRY_SESSION:
 849                 /*
 850                  * If we sent a smaller connect_seq than the peer has, try
 851                  * again with a larger value.
 852                  */
 853                 dout("process_connect got RETRY_SESSION my seq %u, peer %u\n",
 854                      le32_to_cpu(con->v1.out_connect.connect_seq),
 855                      le32_to_cpu(con->v1.in_reply.connect_seq));
 856                 con->v1.connect_seq = le32_to_cpu(con->v1.in_reply.connect_seq);
 857                 con_out_kvec_reset(con);
 858                 ret = prepare_write_connect(con);
 859                 if (ret < 0)
 860                         return ret;
 861                 prepare_read_connect(con);
 862                 break;
 863
 864         case CEPH_MSGR_TAG_RETRY_GLOBAL:
 865                 /*
 866                  * If we sent a smaller global_seq than the peer has, try
 867                  * again with a larger value.
 868                  */
 869                 dout("process_connect got RETRY_GLOBAL my %u peer_gseq %u\n",
 870                      con->v1.peer_global_seq,
 871                      le32_to_cpu(con->v1.in_reply.global_seq));
 872                 ceph_get_global_seq(con->msgr,
 873                                     le32_to_cpu(con->v1.in_reply.global_seq));
 874                 con_out_kvec_reset(con);
 875                 ret = prepare_write_connect(con);
 876                 if (ret < 0)
 877                         return ret;
 878                 prepare_read_connect(con);
 879                 break;
 880
 881         case CEPH_MSGR_TAG_SEQ:
 882         case CEPH_MSGR_TAG_READY:
 883                 if (req_feat & ~server_feat) {
 884                         pr_err("%s%lld %s protocol feature mismatch,"
 885                                " my required %llx > server's %llx, need %llx\n",
 886                                ENTITY_NAME(con->peer_name),
 887                                ceph_pr_addr(&con->peer_addr),
 888                                req_feat, server_feat, req_feat & ~server_feat);
 889                         con->error_msg = "missing required protocol features";
 890                         return -1;
 891                 }
 892
 893                 WARN_ON(con->state != CEPH_CON_S_V1_CONNECT_MSG);
 894                 con->state = CEPH_CON_S_OPEN;
 895                 con->v1.auth_retry = 0;    /* we authenticated; clear flag */
 896                 con->v1.peer_global_seq =
 897                         le32_to_cpu(con->v1.in_reply.global_seq);
 898                 con->v1.connect_seq++;
 899                 con->peer_features = server_feat;
 900                 dout("process_connect got READY gseq %d cseq %d (%d)\n",
 901                      con->v1.peer_global_seq,
 902                      le32_to_cpu(con->v1.in_reply.connect_seq),
 903                      con->v1.connect_seq);
 904                 WARN_ON(con->v1.connect_seq !=
 905                         le32_to_cpu(con->v1.in_reply.connect_seq));
 906
 907                 if (con->v1.in_reply.flags & CEPH_MSG_CONNECT_LOSSY)
 908                         ceph_con_flag_set(con, CEPH_CON_F_LOSSYTX);
 909
 910                 con->delay = 0;      /* reset backoff memory */
 911
 912                 if (con->v1.in_reply.tag == CEPH_MSGR_TAG_SEQ) {
 913                         prepare_write_seq(con);
 914                         prepare_read_seq(con);
 915                 } else {
 916                         prepare_read_tag(con);
 917                 }
 918                 break;
 919
 920         case CEPH_MSGR_TAG_WAIT:
 921                 /*
 922                  * If there is a connection race (we are opening
 923                  * connections to each other), one of us may just have
 924                  * to WAIT.  This shouldn't happen if we are the
 925                  * client.
 926                  */
 927                 con->error_msg = "protocol error, got WAIT as client";
 928                 return -1;
 929
 930         default:
 931                 con->error_msg = "protocol error, garbage tag during connect";
 932                 return -1;
 933         }
 934         return 0;
 935 }
 936
 937 /*
 938  * read (part of) an ack
 939  */
 940 static int read_partial_ack(struct ceph_connection *con)
 941 {
 942         int size = sizeof(con->v1.in_temp_ack);
 943         int end = size;
 944
 945         return read_partial(con, end, size, &con->v1.in_temp_ack);
 946 }
 947
 948 /*
 949  * We can finally discard anything that's been acked.
 950  */
 951 static void process_ack(struct ceph_connection *con)
 952 {
 953         u64 ack = le64_to_cpu(con->v1.in_temp_ack);
 954
 955         if (con->v1.in_tag == CEPH_MSGR_TAG_ACK)
 956                 ceph_con_discard_sent(con, ack);
 957         else
 958                 ceph_con_discard_requeued(con, ack);
 959
 960         prepare_read_tag(con);
 961 }
 962
 963 static int read_partial_message_section(struct ceph_connection *con,
 964                                         struct kvec *section,
 965                                         unsigned int sec_len, u32 *crc)
 966 {
 967         int ret, left;
 968
 969         BUG_ON(!section);
 970
 971         while (section->iov_len < sec_len) {
 972                 BUG_ON(section->iov_base == NULL);
 973                 left = sec_len - section->iov_len;
 974                 ret = ceph_tcp_recvmsg(con->sock, (char *)section->iov_base +
 975                                        section->iov_len, left);
 976                 if (ret <= 0)
 977                         return ret;
 978                 section->iov_len += ret;
 979         }
 980         if (section->iov_len == sec_len)
 981                 *crc = crc32c(0, section->iov_base, section->iov_len);
 982
 983         return 1;
 984 }
 985
 986 static int read_partial_msg_data(struct ceph_connection *con)
 987 {
 988         struct ceph_msg_data_cursor *cursor = &con->in_msg->cursor;
 989         bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC);
 990         struct page *page;
 991         size_t page_offset;
 992         size_t length;
 993         u32 crc = 0;
 994         int ret;
 995
 996         if (do_datacrc)
 997                 crc = con->in_data_crc;
 998         while (cursor->total_resid) {
 999                 if (!cursor->resid) {
1000                         ceph_msg_data_advance(cursor, 0);
1001                         continue;
1002                 }
1003
1004                 page = ceph_msg_data_next(cursor, &page_offset, &length);
1005                 ret = ceph_tcp_recvpage(con->sock, page, page_offset, length);
1006                 if (ret <= 0) {
1007                         if (do_datacrc)
1008                                 con->in_data_crc = crc;
1009
1010                         return ret;
1011                 }
1012
1013                 if (do_datacrc)
1014                         crc = ceph_crc32c_page(crc, page, page_offset, ret);
1015                 ceph_msg_data_advance(cursor, (size_t)ret);
1016         }
1017         if (do_datacrc)
1018                 con->in_data_crc = crc;
1019
1020         return 1;       /* must return > 0 to indicate success */
1021 }
1022
1023 static int read_partial_msg_data_bounce(struct ceph_connection *con)
1024 {
1025         struct ceph_msg_data_cursor *cursor = &con->in_msg->cursor;
1026         struct page *page;
1027         size_t off, len;
1028         u32 crc;
1029         int ret;
1030
1031         if (unlikely(!con->bounce_page)) {
1032                 con->bounce_page = alloc_page(GFP_NOIO);
1033                 if (!con->bounce_page) {
1034                         pr_err("failed to allocate bounce page\n");
1035                         return -ENOMEM;
1036                 }
1037         }
1038
1039         crc = con->in_data_crc;
1040         while (cursor->total_resid) {
1041                 if (!cursor->resid) {
1042                         ceph_msg_data_advance(cursor, 0);
1043                         continue;
1044                 }
1045
1046                 page = ceph_msg_data_next(cursor, &off, &len);
1047                 ret = ceph_tcp_recvpage(con->sock, con->bounce_page, 0, len);
1048                 if (ret <= 0) {
1049                         con->in_data_crc = crc;
1050                         return ret;
1051                 }
1052
1053                 crc = crc32c(crc, page_address(con->bounce_page), ret);
1054                 memcpy_to_page(page, off, page_address(con->bounce_page), ret);
1055
1056                 ceph_msg_data_advance(cursor, ret);
1057         }
1058         con->in_data_crc = crc;
1059
1060         return 1;       /* must return > 0 to indicate success */
1061 }
1062
1063 /*
1064  * read (part of) a message.
1065  */
1066 static int read_partial_message(struct ceph_connection *con)
1067 {
1068         struct ceph_msg *m = con->in_msg;
1069         int size;
1070         int end;
1071         int ret;
1072         unsigned int front_len, middle_len, data_len;
1073         bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC);
1074         bool need_sign = (con->peer_features & CEPH_FEATURE_MSG_AUTH);
1075         u64 seq;
1076         u32 crc;
1077
1078         dout("read_partial_message con %p msg %p\n", con, m);
1079
1080         /* header */
1081         size = sizeof(con->v1.in_hdr);
1082         end = size;
1083         ret = read_partial(con, end, size, &con->v1.in_hdr);
1084         if (ret <= 0)
1085                 return ret;
1086
1087         crc = crc32c(0, &con->v1.in_hdr, offsetof(struct ceph_msg_header, crc));
1088         if (cpu_to_le32(crc) != con->v1.in_hdr.crc) {
1089                 pr_err("read_partial_message bad hdr crc %u != expected %u\n",
1090                        crc, con->v1.in_hdr.crc);
1091                 return -EBADMSG;
1092         }
1093
1094         front_len = le32_to_cpu(con->v1.in_hdr.front_len);
1095         if (front_len > CEPH_MSG_MAX_FRONT_LEN)
1096                 return -EIO;
1097         middle_len = le32_to_cpu(con->v1.in_hdr.middle_len);
1098         if (middle_len > CEPH_MSG_MAX_MIDDLE_LEN)
1099                 return -EIO;
1100         data_len = le32_to_cpu(con->v1.in_hdr.data_len);
1101         if (data_len > CEPH_MSG_MAX_DATA_LEN)
1102                 return -EIO;
1103
1104         /* verify seq# */
1105         seq = le64_to_cpu(con->v1.in_hdr.seq);
1106         if ((s64)seq - (s64)con->in_seq < 1) {
1107                 pr_info("skipping %s%lld %s seq %lld expected %lld\n",
1108                         ENTITY_NAME(con->peer_name),
1109                         ceph_pr_addr(&con->peer_addr),
1110                         seq, con->in_seq + 1);
1111                 con->v1.in_base_pos = -front_len - middle_len - data_len -
1112                                       sizeof_footer(con);
1113                 con->v1.in_tag = CEPH_MSGR_TAG_READY;
1114                 return 1;
1115         } else if ((s64)seq - (s64)con->in_seq > 1) {
1116                 pr_err("read_partial_message bad seq %lld expected %lld\n",
1117                        seq, con->in_seq + 1);
1118                 con->error_msg = "bad message sequence # for incoming message";
1119                 return -EBADE;
1120         }
1121
1122         /* allocate message? */
1123         if (!con->in_msg) {
1124                 int skip = 0;
1125
1126                 dout("got hdr type %d front %d data %d\n", con->v1.in_hdr.type,
1127                      front_len, data_len);
1128                 ret = ceph_con_in_msg_alloc(con, &con->v1.in_hdr, &skip);
1129                 if (ret < 0)
1130                         return ret;
1131
1132                 BUG_ON((!con->in_msg) ^ skip);
1133                 if (skip) {
1134                         /* skip this message */
1135                         dout("alloc_msg said skip message\n");
1136                         con->v1.in_base_pos = -front_len - middle_len -
1137                                               data_len - sizeof_footer(con);
1138                         con->v1.in_tag = CEPH_MSGR_TAG_READY;
1139                         con->in_seq++;
1140                         return 1;
1141                 }
1142
1143                 BUG_ON(!con->in_msg);
1144                 BUG_ON(con->in_msg->con != con);
1145                 m = con->in_msg;
1146                 m->front.iov_len = 0;    /* haven't read it yet */
1147                 if (m->middle)
1148                         m->middle->vec.iov_len = 0;
1149
1150                 /* prepare for data payload, if any */
1151
1152                 if (data_len)
1153                         prepare_message_data(con->in_msg, data_len);
1154         }
1155
1156         /* front */
1157         ret = read_partial_message_section(con, &m->front, front_len,
1158                                            &con->in_front_crc);
1159         if (ret <= 0)
1160                 return ret;
1161
1162         /* middle */
1163         if (m->middle) {
1164                 ret = read_partial_message_section(con, &m->middle->vec,
1165                                                    middle_len,
1166                                                    &con->in_middle_crc);
1167                 if (ret <= 0)
1168                         return ret;
1169         }
1170
1171         /* (page) data */
1172         if (data_len) {
1173                 if (!m->num_data_items)
1174                         return -EIO;
1175
1176                 if (ceph_test_opt(from_msgr(con->msgr), RXBOUNCE))
1177                         ret = read_partial_msg_data_bounce(con);
1178                 else
1179                         ret = read_partial_msg_data(con);
1180                 if (ret <= 0)
1181                         return ret;
1182         }
1183
1184         /* footer */
1185         size = sizeof_footer(con);
1186         end += size;
1187         ret = read_partial(con, end, size, &m->footer);
1188         if (ret <= 0)
1189                 return ret;
1190
1191         if (!need_sign) {
1192                 m->footer.flags = m->old_footer.flags;
1193                 m->footer.sig = 0;
1194         }
1195
1196         dout("read_partial_message got msg %p %d (%u) + %d (%u) + %d (%u)\n",
1197              m, front_len, m->footer.front_crc, middle_len,
1198              m->footer.middle_crc, data_len, m->footer.data_crc);
1199
1200         /* crc ok? */
1201         if (con->in_front_crc != le32_to_cpu(m->footer.front_crc)) {
1202                 pr_err("read_partial_message %p front crc %u != exp. %u\n",
1203                        m, con->in_front_crc, m->footer.front_crc);
1204                 return -EBADMSG;
1205         }
1206         if (con->in_middle_crc != le32_to_cpu(m->footer.middle_crc)) {
1207                 pr_err("read_partial_message %p middle crc %u != exp %u\n",
1208                        m, con->in_middle_crc, m->footer.middle_crc);
1209                 return -EBADMSG;
1210         }
1211         if (do_datacrc &&
1212             (m->footer.flags & CEPH_MSG_FOOTER_NOCRC) == 0 &&
1213             con->in_data_crc != le32_to_cpu(m->footer.data_crc)) {
1214                 pr_err("read_partial_message %p data crc %u != exp. %u\n", m,
1215                        con->in_data_crc, le32_to_cpu(m->footer.data_crc));
1216                 return -EBADMSG;
1217         }
1218
1219         if (need_sign && con->ops->check_message_signature &&
1220             con->ops->check_message_signature(m)) {
1221                 pr_err("read_partial_message %p signature check failed\n", m);
1222                 return -EBADMSG;
1223         }
1224
1225         return 1; /* done! */
1226 }
1227
1228 static int read_keepalive_ack(struct ceph_connection *con)
1229 {
1230         struct ceph_timespec ceph_ts;
1231         size_t size = sizeof(ceph_ts);
1232         int ret = read_partial(con, size, size, &ceph_ts);
1233         if (ret <= 0)
1234                 return ret;
1235         ceph_decode_timespec64(&con->last_keepalive_ack, &ceph_ts);
1236         prepare_read_tag(con);
1237         return 1;
1238 }
1239
1240 /*
1241  * Read what we can from the socket.
1242  */
1243 int ceph_con_v1_try_read(struct ceph_connection *con)
1244 {
1245         int ret = -1;
1246
1247 more:
1248         dout("try_read start %p state %d\n", con, con->state);
1249         if (con->state != CEPH_CON_S_V1_BANNER &&
1250             con->state != CEPH_CON_S_V1_CONNECT_MSG &&
1251             con->state != CEPH_CON_S_OPEN)
1252                 return 0;
1253
1254         BUG_ON(!con->sock);
1255
1256         dout("try_read tag %d in_base_pos %d\n", con->v1.in_tag,
1257              con->v1.in_base_pos);
1258
1259         if (con->state == CEPH_CON_S_V1_BANNER) {
1260                 ret = read_partial_banner(con);
1261                 if (ret <= 0)
1262                         goto out;
1263                 ret = process_banner(con);
1264                 if (ret < 0)
1265                         goto out;
1266
1267                 con->state = CEPH_CON_S_V1_CONNECT_MSG;
1268
1269                 /*
1270                  * Received banner is good, exchange connection info.
1271                  * Do not reset out_kvec, as sending our banner raced
1272                  * with receiving peer banner after connect completed.
1273                  */
1274                 ret = prepare_write_connect(con);
1275                 if (ret < 0)
1276                         goto out;
1277                 prepare_read_connect(con);
1278
1279                 /* Send connection info before awaiting response */
1280                 goto out;
1281         }
1282
1283         if (con->state == CEPH_CON_S_V1_CONNECT_MSG) {
1284                 ret = read_partial_connect(con);
1285                 if (ret <= 0)
1286                         goto out;
1287                 ret = process_connect(con);
1288                 if (ret < 0)
1289                         goto out;
1290                 goto more;
1291         }
1292
1293         WARN_ON(con->state != CEPH_CON_S_OPEN);
1294
1295         if (con->v1.in_base_pos < 0) {
1296                 /*
1297                  * skipping + discarding content.
1298                  */
1299                 ret = ceph_tcp_recvmsg(con->sock, NULL, -con->v1.in_base_pos);
1300                 if (ret <= 0)
1301                         goto out;
1302                 dout("skipped %d / %d bytes\n", ret, -con->v1.in_base_pos);
1303                 con->v1.in_base_pos += ret;
1304                 if (con->v1.in_base_pos)
1305                         goto more;
1306         }
1307         if (con->v1.in_tag == CEPH_MSGR_TAG_READY) {
1308                 /*
1309                  * what's next?
1310                  */
1311                 ret = ceph_tcp_recvmsg(con->sock, &con->v1.in_tag, 1);
1312                 if (ret <= 0)
1313                         goto out;
1314                 dout("try_read got tag %d\n", con->v1.in_tag);
1315                 switch (con->v1.in_tag) {
1316                 case CEPH_MSGR_TAG_MSG:
1317                         prepare_read_message(con);
1318                         break;
1319                 case CEPH_MSGR_TAG_ACK:
1320                         prepare_read_ack(con);
1321                         break;
1322                 case CEPH_MSGR_TAG_KEEPALIVE2_ACK:
1323                         prepare_read_keepalive_ack(con);
1324                         break;
1325                 case CEPH_MSGR_TAG_CLOSE:
1326                         ceph_con_close_socket(con);
1327                         con->state = CEPH_CON_S_CLOSED;
1328                         goto out;
1329                 default:
1330                         goto bad_tag;
1331                 }
1332         }
1333         if (con->v1.in_tag == CEPH_MSGR_TAG_MSG) {
1334                 ret = read_partial_message(con);
1335                 if (ret <= 0) {
1336                         switch (ret) {
1337                         case -EBADMSG:
1338                                 con->error_msg = "bad crc/signature";
1339                                 fallthrough;
1340                         case -EBADE:
1341                                 ret = -EIO;
1342                                 break;
1343                         case -EIO:
1344                                 con->error_msg = "io error";
1345                                 break;
1346                         }
1347                         goto out;
1348                 }
1349                 if (con->v1.in_tag == CEPH_MSGR_TAG_READY)
1350                         goto more;
1351                 ceph_con_process_message(con);
1352                 if (con->state == CEPH_CON_S_OPEN)
1353                         prepare_read_tag(con);
1354                 goto more;
1355         }
1356         if (con->v1.in_tag == CEPH_MSGR_TAG_ACK ||
1357             con->v1.in_tag == CEPH_MSGR_TAG_SEQ) {
1358                 /*
1359                  * the final handshake seq exchange is semantically
1360                  * equivalent to an ACK
1361                  */
1362                 ret = read_partial_ack(con);
1363                 if (ret <= 0)
1364                         goto out;
1365                 process_ack(con);
1366                 goto more;
1367         }
1368         if (con->v1.in_tag == CEPH_MSGR_TAG_KEEPALIVE2_ACK) {
1369                 ret = read_keepalive_ack(con);
1370                 if (ret <= 0)
1371                         goto out;
1372                 goto more;
1373         }
1374
1375 out:
1376         dout("try_read done on %p ret %d\n", con, ret);
1377         return ret;
1378
1379 bad_tag:
1380         pr_err("try_read bad tag %d\n", con->v1.in_tag);
1381         con->error_msg = "protocol error, garbage tag";
1382         ret = -1;
1383         goto out;
1384 }
1385
1386 /*
1387  * Write something to the socket.  Called in a worker thread when the
1388  * socket appears to be writeable and we have something ready to send.
1389  */
1390 int ceph_con_v1_try_write(struct ceph_connection *con)
1391 {
1392         int ret = 1;
1393
1394         dout("try_write start %p state %d\n", con, con->state);
1395         if (con->state != CEPH_CON_S_PREOPEN &&
1396             con->state != CEPH_CON_S_V1_BANNER &&
1397             con->state != CEPH_CON_S_V1_CONNECT_MSG &&
1398             con->state != CEPH_CON_S_OPEN)
1399                 return 0;
1400
1401         /* open the socket first? */
1402         if (con->state == CEPH_CON_S_PREOPEN) {
1403                 BUG_ON(con->sock);
1404                 con->state = CEPH_CON_S_V1_BANNER;
1405
1406                 con_out_kvec_reset(con);
1407                 prepare_write_banner(con);
1408                 prepare_read_banner(con);
1409
1410                 BUG_ON(con->in_msg);
1411                 con->v1.in_tag = CEPH_MSGR_TAG_READY;
1412                 dout("try_write initiating connect on %p new state %d\n",
1413                      con, con->state);
1414                 ret = ceph_tcp_connect(con);
1415                 if (ret < 0) {
1416                         con->error_msg = "connect error";
1417                         goto out;
1418                 }
1419         }
1420
1421 more:
1422         dout("try_write out_kvec_bytes %d\n", con->v1.out_kvec_bytes);
1423         BUG_ON(!con->sock);
1424
1425         /* kvec data queued? */
1426         if (con->v1.out_kvec_left) {
1427                 ret = write_partial_kvec(con);
1428                 if (ret <= 0)
1429                         goto out;
1430         }
1431         if (con->v1.out_skip) {
1432                 ret = write_partial_skip(con);
1433                 if (ret <= 0)
1434                         goto out;
1435         }
1436
1437         /* msg pages? */
1438         if (con->out_msg) {
1439                 if (con->v1.out_msg_done) {
1440                         ceph_msg_put(con->out_msg);
1441                         con->out_msg = NULL;   /* we're done with this one */
1442                         goto do_next;
1443                 }
1444
1445                 ret = write_partial_message_data(con);
1446                 if (ret == 1)
1447                         goto more;  /* we need to send the footer, too! */
1448                 if (ret == 0)
1449                         goto out;
1450                 if (ret < 0) {
1451                         dout("try_write write_partial_message_data err %d\n",
1452                              ret);
1453                         goto out;
1454                 }
1455         }
1456
1457 do_next:
1458         if (con->state == CEPH_CON_S_OPEN) {
1459                 if (ceph_con_flag_test_and_clear(con,
1460                                 CEPH_CON_F_KEEPALIVE_PENDING)) {
1461                         prepare_write_keepalive(con);
1462                         goto more;
1463                 }
1464                 /* is anything else pending? */
1465                 if (!list_empty(&con->out_queue)) {
1466                         prepare_write_message(con);
1467                         goto more;
1468                 }
1469                 if (con->in_seq > con->in_seq_acked) {
1470                         prepare_write_ack(con);
1471                         goto more;
1472                 }
1473         }
1474
1475         /* Nothing to do! */
1476         ceph_con_flag_clear(con, CEPH_CON_F_WRITE_PENDING);
1477         dout("try_write nothing else to write.\n");
1478         ret = 0;
1479 out:
1480         dout("try_write done on %p ret %d\n", con, ret);
1481         return ret;
1482 }
1483
1484 void ceph_con_v1_revoke(struct ceph_connection *con)
1485 {
1486         struct ceph_msg *msg = con->out_msg;
1487
1488         WARN_ON(con->v1.out_skip);
1489         /* footer */
1490         if (con->v1.out_msg_done) {
1491                 con->v1.out_skip += con_out_kvec_skip(con);
1492         } else {
1493                 WARN_ON(!msg->data_length);
1494                 con->v1.out_skip += sizeof_footer(con);
1495         }
1496         /* data, middle, front */
1497         if (msg->data_length)
1498                 con->v1.out_skip += msg->cursor.total_resid;
1499         if (msg->middle)
1500                 con->v1.out_skip += con_out_kvec_skip(con);
1501         con->v1.out_skip += con_out_kvec_skip(con);
1502
1503         dout("%s con %p out_kvec_bytes %d out_skip %d\n", __func__, con,
1504              con->v1.out_kvec_bytes, con->v1.out_skip);
1505 }
1506
1507 void ceph_con_v1_revoke_incoming(struct ceph_connection *con)
1508 {
1509         unsigned int front_len = le32_to_cpu(con->v1.in_hdr.front_len);
1510         unsigned int middle_len = le32_to_cpu(con->v1.in_hdr.middle_len);
1511         unsigned int data_len = le32_to_cpu(con->v1.in_hdr.data_len);
1512
1513         /* skip rest of message */
1514         con->v1.in_base_pos = con->v1.in_base_pos -
1515                         sizeof(struct ceph_msg_header) -
1516                         front_len -
1517                         middle_len -
1518                         data_len -
1519                         sizeof(struct ceph_msg_footer);
1520
1521         con->v1.in_tag = CEPH_MSGR_TAG_READY;
1522         con->in_seq++;
1523
1524         dout("%s con %p in_base_pos %d\n", __func__, con, con->v1.in_base_pos);
1525 }
1526
1527 bool ceph_con_v1_opened(struct ceph_connection *con)
1528 {
1529         return con->v1.connect_seq;
1530 }
1531
1532 void ceph_con_v1_reset_session(struct ceph_connection *con)
1533 {
1534         con->v1.connect_seq = 0;
1535         con->v1.peer_global_seq = 0;
1536 }
1537
1538 void ceph_con_v1_reset_protocol(struct ceph_connection *con)
1539 {
1540         con->v1.out_skip = 0;
1541 }