1 /* 2 * iSCSI Initiator over TCP/IP Data-Path 3 * 4 * Copyright (C) 2004 Dmitry Yusupov 5 * Copyright (C) 2004 Alex Aizman 6 * Copyright (C) 2005 - 2006 Mike Christie 7 * Copyright (C) 2006 Red Hat, Inc. All rights reserved. 8 * maintained by open-iscsi@googlegroups.com 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published 12 * by the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * See the file COPYING included with this distribution for more details. 21 * 22 * Credits: 23 * Christoph Hellwig 24 * FUJITA Tomonori 25 * Arne Redlich 26 * Zhenyu Wang 27 */ 28 29 #include <linux/types.h> 30 #include <linux/inet.h> 31 #include <linux/file.h> 32 #include <linux/blkdev.h> 33 #include <linux/crypto.h> 34 #include <linux/delay.h> 35 #include <linux/kfifo.h> 36 #include <linux/scatterlist.h> 37 #include <net/tcp.h> 38 #include <scsi/scsi_cmnd.h> 39 #include <scsi/scsi_device.h> 40 #include <scsi/scsi_host.h> 41 #include <scsi/scsi.h> 42 #include <scsi/scsi_transport_iscsi.h> 43 44 #include "iscsi_tcp.h" 45 46 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, " 47 "Dmitry Yusupov <dmitry_yus@yahoo.com>, " 48 "Alex Aizman <itn780@yahoo.com>"); 49 MODULE_DESCRIPTION("iSCSI/TCP data-path"); 50 MODULE_LICENSE("GPL"); 51 52 static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport; 53 static struct scsi_host_template iscsi_sw_tcp_sht; 54 static struct iscsi_transport iscsi_sw_tcp_transport; 55 56 static unsigned int iscsi_max_lun = 512; 57 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO); 58 59 static int iscsi_sw_tcp_dbg; 60 module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int, 61 S_IRUGO | S_IWUSR); 62 MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module " 63 "Set to 1 to turn on, and zero to turn off. Default is off."); 64 65 #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \ 66 do { \ 67 if (iscsi_sw_tcp_dbg) \ 68 iscsi_conn_printk(KERN_INFO, _conn, \ 69 "%s " dbg_fmt, \ 70 __func__, ##arg); \ 71 } while (0); 72 73 74 /** 75 * iscsi_sw_tcp_recv - TCP receive in sendfile fashion 76 * @rd_desc: read descriptor 77 * @skb: socket buffer 78 * @offset: offset in skb 79 * @len: skb->len - offset 80 */ 81 static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, 82 unsigned int offset, size_t len) 83 { 84 struct iscsi_conn *conn = rd_desc->arg.data; 85 unsigned int consumed, total_consumed = 0; 86 int status; 87 88 ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset); 89 90 do { 91 status = 0; 92 consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status); 93 offset += consumed; 94 total_consumed += consumed; 95 } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE); 96 97 ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n", 98 skb->len - offset, status); 99 return total_consumed; 100 } 101 102 static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag) 103 { 104 struct iscsi_conn *conn = sk->sk_user_data; 105 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 106 read_descriptor_t rd_desc; 107 108 read_lock(&sk->sk_callback_lock); 109 110 /* 111 * Use rd_desc to pass 'conn' to iscsi_tcp_recv. 112 * We set count to 1 because we want the network layer to 113 * hand us all the skbs that are available. iscsi_tcp_recv 114 * handled pdus that cross buffers or pdus that still need data. 115 */ 116 rd_desc.arg.data = conn; 117 rd_desc.count = 1; 118 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv); 119 120 read_unlock(&sk->sk_callback_lock); 121 122 /* If we had to (atomically) map a highmem page, 123 * unmap it now. */ 124 iscsi_tcp_segment_unmap(&tcp_conn->in.segment); 125 } 126 127 static void iscsi_sw_tcp_state_change(struct sock *sk) 128 { 129 struct iscsi_tcp_conn *tcp_conn; 130 struct iscsi_sw_tcp_conn *tcp_sw_conn; 131 struct iscsi_conn *conn; 132 struct iscsi_session *session; 133 void (*old_state_change)(struct sock *); 134 135 read_lock(&sk->sk_callback_lock); 136 137 conn = (struct iscsi_conn*)sk->sk_user_data; 138 session = conn->session; 139 140 if ((sk->sk_state == TCP_CLOSE_WAIT || 141 sk->sk_state == TCP_CLOSE) && 142 !atomic_read(&sk->sk_rmem_alloc)) { 143 ISCSI_SW_TCP_DBG(conn, "iscsi_tcp_state_change: " 144 "TCP_CLOSE|TCP_CLOSE_WAIT\n"); 145 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); 146 } 147 148 tcp_conn = conn->dd_data; 149 tcp_sw_conn = tcp_conn->dd_data; 150 old_state_change = tcp_sw_conn->old_state_change; 151 152 read_unlock(&sk->sk_callback_lock); 153 154 old_state_change(sk); 155 } 156 157 /** 158 * iscsi_write_space - Called when more output buffer space is available 159 * @sk: socket space is available for 160 **/ 161 static void iscsi_sw_tcp_write_space(struct sock *sk) 162 { 163 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data; 164 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 165 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 166 167 tcp_sw_conn->old_write_space(sk); 168 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n"); 169 iscsi_conn_queue_work(conn); 170 } 171 172 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn) 173 { 174 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 175 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 176 struct sock *sk = tcp_sw_conn->sock->sk; 177 178 /* assign new callbacks */ 179 write_lock_bh(&sk->sk_callback_lock); 180 sk->sk_user_data = conn; 181 tcp_sw_conn->old_data_ready = sk->sk_data_ready; 182 tcp_sw_conn->old_state_change = sk->sk_state_change; 183 tcp_sw_conn->old_write_space = sk->sk_write_space; 184 sk->sk_data_ready = iscsi_sw_tcp_data_ready; 185 sk->sk_state_change = iscsi_sw_tcp_state_change; 186 sk->sk_write_space = iscsi_sw_tcp_write_space; 187 write_unlock_bh(&sk->sk_callback_lock); 188 } 189 190 static void 191 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn) 192 { 193 struct sock *sk = tcp_sw_conn->sock->sk; 194 195 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */ 196 write_lock_bh(&sk->sk_callback_lock); 197 sk->sk_user_data = NULL; 198 sk->sk_data_ready = tcp_sw_conn->old_data_ready; 199 sk->sk_state_change = tcp_sw_conn->old_state_change; 200 sk->sk_write_space = tcp_sw_conn->old_write_space; 201 sk->sk_no_check = 0; 202 write_unlock_bh(&sk->sk_callback_lock); 203 } 204 205 /** 206 * iscsi_sw_tcp_xmit_segment - transmit segment 207 * @tcp_conn: the iSCSI TCP connection 208 * @segment: the buffer to transmnit 209 * 210 * This function transmits as much of the buffer as 211 * the network layer will accept, and returns the number of 212 * bytes transmitted. 213 * 214 * If CRC hashing is enabled, the function will compute the 215 * hash as it goes. When the entire segment has been transmitted, 216 * it will retrieve the hash value and send it as well. 217 */ 218 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn, 219 struct iscsi_segment *segment) 220 { 221 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 222 struct socket *sk = tcp_sw_conn->sock; 223 unsigned int copied = 0; 224 int r = 0; 225 226 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) { 227 struct scatterlist *sg; 228 unsigned int offset, copy; 229 int flags = 0; 230 231 r = 0; 232 offset = segment->copied; 233 copy = segment->size - offset; 234 235 if (segment->total_copied + segment->size < segment->total_size) 236 flags |= MSG_MORE; 237 238 /* Use sendpage if we can; else fall back to sendmsg */ 239 if (!segment->data) { 240 sg = segment->sg; 241 offset += segment->sg_offset + sg->offset; 242 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset, 243 copy, flags); 244 } else { 245 struct msghdr msg = { .msg_flags = flags }; 246 struct kvec iov = { 247 .iov_base = segment->data + offset, 248 .iov_len = copy 249 }; 250 251 r = kernel_sendmsg(sk, &msg, &iov, 1, copy); 252 } 253 254 if (r < 0) { 255 iscsi_tcp_segment_unmap(segment); 256 return r; 257 } 258 copied += r; 259 } 260 return copied; 261 } 262 263 /** 264 * iscsi_sw_tcp_xmit - TCP transmit 265 **/ 266 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn) 267 { 268 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 269 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 270 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 271 unsigned int consumed = 0; 272 int rc = 0; 273 274 while (1) { 275 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment); 276 /* 277 * We may not have been able to send data because the conn 278 * is getting stopped. libiscsi will know so propogate err 279 * for it to do the right thing. 280 */ 281 if (rc == -EAGAIN) 282 return rc; 283 else if (rc < 0) { 284 rc = ISCSI_ERR_XMIT_FAILED; 285 goto error; 286 } else if (rc == 0) 287 break; 288 289 consumed += rc; 290 291 if (segment->total_copied >= segment->total_size) { 292 if (segment->done != NULL) { 293 rc = segment->done(tcp_conn, segment); 294 if (rc != 0) 295 goto error; 296 } 297 } 298 } 299 300 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed); 301 302 conn->txdata_octets += consumed; 303 return consumed; 304 305 error: 306 /* Transmit error. We could initiate error recovery 307 * here. */ 308 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc); 309 iscsi_conn_failure(conn, rc); 310 return -EIO; 311 } 312 313 /** 314 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit 315 */ 316 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn) 317 { 318 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 319 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 320 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 321 322 return segment->total_copied - segment->total_size; 323 } 324 325 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task) 326 { 327 struct iscsi_conn *conn = task->conn; 328 int rc; 329 330 while (iscsi_sw_tcp_xmit_qlen(conn)) { 331 rc = iscsi_sw_tcp_xmit(conn); 332 if (rc == 0) 333 return -EAGAIN; 334 if (rc < 0) 335 return rc; 336 } 337 338 return 0; 339 } 340 341 /* 342 * This is called when we're done sending the header. 343 * Simply copy the data_segment to the send segment, and return. 344 */ 345 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn, 346 struct iscsi_segment *segment) 347 { 348 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 349 350 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment; 351 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn, 352 "Header done. Next segment size %u total_size %u\n", 353 tcp_sw_conn->out.segment.size, 354 tcp_sw_conn->out.segment.total_size); 355 return 0; 356 } 357 358 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, 359 size_t hdrlen) 360 { 361 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 362 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 363 364 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ? 365 "digest enabled" : "digest disabled"); 366 367 /* Clear the data segment - needs to be filled in by the 368 * caller using iscsi_tcp_send_data_prep() */ 369 memset(&tcp_sw_conn->out.data_segment, 0, 370 sizeof(struct iscsi_segment)); 371 372 /* If header digest is enabled, compute the CRC and 373 * place the digest into the same buffer. We make 374 * sure that both iscsi_tcp_task and mtask have 375 * sufficient room. 376 */ 377 if (conn->hdrdgst_en) { 378 iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen, 379 hdr + hdrlen); 380 hdrlen += ISCSI_DIGEST_SIZE; 381 } 382 383 /* Remember header pointer for later, when we need 384 * to decide whether there's a payload to go along 385 * with the header. */ 386 tcp_sw_conn->out.hdr = hdr; 387 388 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen, 389 iscsi_sw_tcp_send_hdr_done, NULL); 390 } 391 392 /* 393 * Prepare the send buffer for the payload data. 394 * Padding and checksumming will all be taken care 395 * of by the iscsi_segment routines. 396 */ 397 static int 398 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg, 399 unsigned int count, unsigned int offset, 400 unsigned int len) 401 { 402 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 403 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 404 struct hash_desc *tx_hash = NULL; 405 unsigned int hdr_spec_len; 406 407 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len, 408 conn->datadgst_en ? 409 "digest enabled" : "digest disabled"); 410 411 /* Make sure the datalen matches what the caller 412 said he would send. */ 413 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 414 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 415 416 if (conn->datadgst_en) 417 tx_hash = &tcp_sw_conn->tx_hash; 418 419 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment, 420 sg, count, offset, len, 421 NULL, tx_hash); 422 } 423 424 static void 425 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data, 426 size_t len) 427 { 428 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 429 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 430 struct hash_desc *tx_hash = NULL; 431 unsigned int hdr_spec_len; 432 433 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ? 434 "digest enabled" : "digest disabled"); 435 436 /* Make sure the datalen matches what the caller 437 said he would send. */ 438 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 439 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 440 441 if (conn->datadgst_en) 442 tx_hash = &tcp_sw_conn->tx_hash; 443 444 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment, 445 data, len, NULL, tx_hash); 446 } 447 448 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task, 449 unsigned int offset, unsigned int count) 450 { 451 struct iscsi_conn *conn = task->conn; 452 int err = 0; 453 454 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len); 455 456 if (!count) 457 return 0; 458 459 if (!task->sc) 460 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count); 461 else { 462 struct scsi_data_buffer *sdb = scsi_out(task->sc); 463 464 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl, 465 sdb->table.nents, offset, 466 count); 467 } 468 469 if (err) { 470 /* got invalid offset/len */ 471 return -EIO; 472 } 473 return 0; 474 } 475 476 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 477 { 478 struct iscsi_tcp_task *tcp_task = task->dd_data; 479 480 task->hdr = task->dd_data + sizeof(*tcp_task); 481 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE; 482 return 0; 483 } 484 485 static struct iscsi_cls_conn * 486 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session, 487 uint32_t conn_idx) 488 { 489 struct iscsi_conn *conn; 490 struct iscsi_cls_conn *cls_conn; 491 struct iscsi_tcp_conn *tcp_conn; 492 struct iscsi_sw_tcp_conn *tcp_sw_conn; 493 494 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn), 495 conn_idx); 496 if (!cls_conn) 497 return NULL; 498 conn = cls_conn->dd_data; 499 tcp_conn = conn->dd_data; 500 tcp_sw_conn = tcp_conn->dd_data; 501 502 tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0, 503 CRYPTO_ALG_ASYNC); 504 tcp_sw_conn->tx_hash.flags = 0; 505 if (IS_ERR(tcp_sw_conn->tx_hash.tfm)) 506 goto free_conn; 507 508 tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0, 509 CRYPTO_ALG_ASYNC); 510 tcp_sw_conn->rx_hash.flags = 0; 511 if (IS_ERR(tcp_sw_conn->rx_hash.tfm)) 512 goto free_tx_tfm; 513 tcp_conn->rx_hash = &tcp_sw_conn->rx_hash; 514 515 return cls_conn; 516 517 free_tx_tfm: 518 crypto_free_hash(tcp_sw_conn->tx_hash.tfm); 519 free_conn: 520 iscsi_conn_printk(KERN_ERR, conn, 521 "Could not create connection due to crc32c " 522 "loading error. Make sure the crc32c " 523 "module is built as a module or into the " 524 "kernel\n"); 525 iscsi_tcp_conn_teardown(cls_conn); 526 return NULL; 527 } 528 529 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn) 530 { 531 struct iscsi_session *session = conn->session; 532 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 533 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 534 struct socket *sock = tcp_sw_conn->sock; 535 536 if (!sock) 537 return; 538 539 sock_hold(sock->sk); 540 iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn); 541 sock_put(sock->sk); 542 543 spin_lock_bh(&session->lock); 544 tcp_sw_conn->sock = NULL; 545 spin_unlock_bh(&session->lock); 546 sockfd_put(sock); 547 } 548 549 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn) 550 { 551 struct iscsi_conn *conn = cls_conn->dd_data; 552 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 553 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 554 555 iscsi_sw_tcp_release_conn(conn); 556 557 if (tcp_sw_conn->tx_hash.tfm) 558 crypto_free_hash(tcp_sw_conn->tx_hash.tfm); 559 if (tcp_sw_conn->rx_hash.tfm) 560 crypto_free_hash(tcp_sw_conn->rx_hash.tfm); 561 562 iscsi_tcp_conn_teardown(cls_conn); 563 } 564 565 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 566 { 567 struct iscsi_conn *conn = cls_conn->dd_data; 568 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 569 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 570 571 /* userspace may have goofed up and not bound us */ 572 if (!tcp_sw_conn->sock) 573 return; 574 /* 575 * Make sure our recv side is stopped. 576 * Older tools called conn stop before ep_disconnect 577 * so IO could still be coming in. 578 */ 579 write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock); 580 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); 581 write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock); 582 583 iscsi_conn_stop(cls_conn, flag); 584 iscsi_sw_tcp_release_conn(conn); 585 } 586 587 static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock, 588 char *buf, int *port, 589 int (*getname)(struct socket *, 590 struct sockaddr *, 591 int *addrlen)) 592 { 593 struct sockaddr_storage *addr; 594 struct sockaddr_in6 *sin6; 595 struct sockaddr_in *sin; 596 int rc = 0, len; 597 598 addr = kmalloc(sizeof(*addr), GFP_KERNEL); 599 if (!addr) 600 return -ENOMEM; 601 602 if (getname(sock, (struct sockaddr *) addr, &len)) { 603 rc = -ENODEV; 604 goto free_addr; 605 } 606 607 switch (addr->ss_family) { 608 case AF_INET: 609 sin = (struct sockaddr_in *)addr; 610 spin_lock_bh(&conn->session->lock); 611 sprintf(buf, "%pI4", &sin->sin_addr.s_addr); 612 *port = be16_to_cpu(sin->sin_port); 613 spin_unlock_bh(&conn->session->lock); 614 break; 615 case AF_INET6: 616 sin6 = (struct sockaddr_in6 *)addr; 617 spin_lock_bh(&conn->session->lock); 618 sprintf(buf, "%pI6", &sin6->sin6_addr); 619 *port = be16_to_cpu(sin6->sin6_port); 620 spin_unlock_bh(&conn->session->lock); 621 break; 622 } 623 free_addr: 624 kfree(addr); 625 return rc; 626 } 627 628 static int 629 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session, 630 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph, 631 int is_leading) 632 { 633 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 634 struct iscsi_host *ihost = shost_priv(shost); 635 struct iscsi_conn *conn = cls_conn->dd_data; 636 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 637 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 638 struct sock *sk; 639 struct socket *sock; 640 int err; 641 642 /* lookup for existing socket */ 643 sock = sockfd_lookup((int)transport_eph, &err); 644 if (!sock) { 645 iscsi_conn_printk(KERN_ERR, conn, 646 "sockfd_lookup failed %d\n", err); 647 return -EEXIST; 648 } 649 /* 650 * copy these values now because if we drop the session 651 * userspace may still want to query the values since we will 652 * be using them for the reconnect 653 */ 654 err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address, 655 &conn->portal_port, kernel_getpeername); 656 if (err) 657 goto free_socket; 658 659 err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address, 660 &ihost->local_port, kernel_getsockname); 661 if (err) 662 goto free_socket; 663 664 err = iscsi_conn_bind(cls_session, cls_conn, is_leading); 665 if (err) 666 goto free_socket; 667 668 /* bind iSCSI connection and socket */ 669 tcp_sw_conn->sock = sock; 670 671 /* setup Socket parameters */ 672 sk = sock->sk; 673 sk->sk_reuse = 1; 674 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */ 675 sk->sk_allocation = GFP_ATOMIC; 676 677 iscsi_sw_tcp_conn_set_callbacks(conn); 678 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage; 679 /* 680 * set receive state machine into initial state 681 */ 682 iscsi_tcp_hdr_recv_prep(tcp_conn); 683 return 0; 684 685 free_socket: 686 sockfd_put(sock); 687 return err; 688 } 689 690 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn, 691 enum iscsi_param param, char *buf, 692 int buflen) 693 { 694 struct iscsi_conn *conn = cls_conn->dd_data; 695 struct iscsi_session *session = conn->session; 696 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 697 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 698 int value; 699 700 switch(param) { 701 case ISCSI_PARAM_HDRDGST_EN: 702 iscsi_set_param(cls_conn, param, buf, buflen); 703 break; 704 case ISCSI_PARAM_DATADGST_EN: 705 iscsi_set_param(cls_conn, param, buf, buflen); 706 tcp_sw_conn->sendpage = conn->datadgst_en ? 707 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; 708 break; 709 case ISCSI_PARAM_MAX_R2T: 710 sscanf(buf, "%d", &value); 711 if (value <= 0 || !is_power_of_2(value)) 712 return -EINVAL; 713 if (session->max_r2t == value) 714 break; 715 iscsi_tcp_r2tpool_free(session); 716 iscsi_set_param(cls_conn, param, buf, buflen); 717 if (iscsi_tcp_r2tpool_alloc(session)) 718 return -ENOMEM; 719 break; 720 default: 721 return iscsi_set_param(cls_conn, param, buf, buflen); 722 } 723 724 return 0; 725 } 726 727 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn, 728 enum iscsi_param param, char *buf) 729 { 730 struct iscsi_conn *conn = cls_conn->dd_data; 731 int len; 732 733 switch(param) { 734 case ISCSI_PARAM_CONN_PORT: 735 spin_lock_bh(&conn->session->lock); 736 len = sprintf(buf, "%hu\n", conn->portal_port); 737 spin_unlock_bh(&conn->session->lock); 738 break; 739 case ISCSI_PARAM_CONN_ADDRESS: 740 spin_lock_bh(&conn->session->lock); 741 len = sprintf(buf, "%s\n", conn->portal_address); 742 spin_unlock_bh(&conn->session->lock); 743 break; 744 default: 745 return iscsi_conn_get_param(cls_conn, param, buf); 746 } 747 748 return len; 749 } 750 751 static void 752 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, 753 struct iscsi_stats *stats) 754 { 755 struct iscsi_conn *conn = cls_conn->dd_data; 756 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 757 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 758 759 stats->custom_length = 3; 760 strcpy(stats->custom[0].desc, "tx_sendpage_failures"); 761 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt; 762 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr"); 763 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt; 764 strcpy(stats->custom[2].desc, "eh_abort_cnt"); 765 stats->custom[2].value = conn->eh_abort_cnt; 766 767 iscsi_tcp_conn_get_stats(cls_conn, stats); 768 } 769 770 static struct iscsi_cls_session * 771 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max, 772 uint16_t qdepth, uint32_t initial_cmdsn) 773 { 774 struct iscsi_cls_session *cls_session; 775 struct iscsi_session *session; 776 struct Scsi_Host *shost; 777 778 if (ep) { 779 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep); 780 return NULL; 781 } 782 783 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, 1); 784 if (!shost) 785 return NULL; 786 shost->transportt = iscsi_sw_tcp_scsi_transport; 787 shost->cmd_per_lun = qdepth; 788 shost->max_lun = iscsi_max_lun; 789 shost->max_id = 0; 790 shost->max_channel = 0; 791 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE; 792 793 if (iscsi_host_add(shost, NULL)) 794 goto free_host; 795 796 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost, 797 cmds_max, 798 sizeof(struct iscsi_tcp_task) + 799 sizeof(struct iscsi_sw_tcp_hdrbuf), 800 initial_cmdsn, 0); 801 if (!cls_session) 802 goto remove_host; 803 session = cls_session->dd_data; 804 805 shost->can_queue = session->scsi_cmds_max; 806 if (iscsi_tcp_r2tpool_alloc(session)) 807 goto remove_session; 808 return cls_session; 809 810 remove_session: 811 iscsi_session_teardown(cls_session); 812 remove_host: 813 iscsi_host_remove(shost); 814 free_host: 815 iscsi_host_free(shost); 816 return NULL; 817 } 818 819 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session) 820 { 821 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 822 823 iscsi_tcp_r2tpool_free(cls_session->dd_data); 824 iscsi_session_teardown(cls_session); 825 826 iscsi_host_remove(shost); 827 iscsi_host_free(shost); 828 } 829 830 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev) 831 { 832 set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags); 833 return 0; 834 } 835 836 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev) 837 { 838 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY); 839 blk_queue_dma_alignment(sdev->request_queue, 0); 840 return 0; 841 } 842 843 static struct scsi_host_template iscsi_sw_tcp_sht = { 844 .module = THIS_MODULE, 845 .name = "iSCSI Initiator over TCP/IP", 846 .queuecommand = iscsi_queuecommand, 847 .change_queue_depth = iscsi_change_queue_depth, 848 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1, 849 .sg_tablesize = 4096, 850 .max_sectors = 0xFFFF, 851 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN, 852 .eh_abort_handler = iscsi_eh_abort, 853 .eh_device_reset_handler= iscsi_eh_device_reset, 854 .eh_target_reset_handler= iscsi_eh_target_reset, 855 .use_clustering = DISABLE_CLUSTERING, 856 .slave_alloc = iscsi_sw_tcp_slave_alloc, 857 .slave_configure = iscsi_sw_tcp_slave_configure, 858 .target_alloc = iscsi_target_alloc, 859 .proc_name = "iscsi_tcp", 860 .this_id = -1, 861 }; 862 863 static struct iscsi_transport iscsi_sw_tcp_transport = { 864 .owner = THIS_MODULE, 865 .name = "tcp", 866 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST 867 | CAP_DATADGST, 868 .param_mask = ISCSI_MAX_RECV_DLENGTH | 869 ISCSI_MAX_XMIT_DLENGTH | 870 ISCSI_HDRDGST_EN | 871 ISCSI_DATADGST_EN | 872 ISCSI_INITIAL_R2T_EN | 873 ISCSI_MAX_R2T | 874 ISCSI_IMM_DATA_EN | 875 ISCSI_FIRST_BURST | 876 ISCSI_MAX_BURST | 877 ISCSI_PDU_INORDER_EN | 878 ISCSI_DATASEQ_INORDER_EN | 879 ISCSI_ERL | 880 ISCSI_CONN_PORT | 881 ISCSI_CONN_ADDRESS | 882 ISCSI_EXP_STATSN | 883 ISCSI_PERSISTENT_PORT | 884 ISCSI_PERSISTENT_ADDRESS | 885 ISCSI_TARGET_NAME | ISCSI_TPGT | 886 ISCSI_USERNAME | ISCSI_PASSWORD | 887 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN | 888 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO | 889 ISCSI_LU_RESET_TMO | 890 ISCSI_PING_TMO | ISCSI_RECV_TMO | 891 ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME, 892 .host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS | 893 ISCSI_HOST_INITIATOR_NAME | 894 ISCSI_HOST_NETDEV_NAME, 895 /* session management */ 896 .create_session = iscsi_sw_tcp_session_create, 897 .destroy_session = iscsi_sw_tcp_session_destroy, 898 /* connection management */ 899 .create_conn = iscsi_sw_tcp_conn_create, 900 .bind_conn = iscsi_sw_tcp_conn_bind, 901 .destroy_conn = iscsi_sw_tcp_conn_destroy, 902 .set_param = iscsi_sw_tcp_conn_set_param, 903 .get_conn_param = iscsi_sw_tcp_conn_get_param, 904 .get_session_param = iscsi_session_get_param, 905 .start_conn = iscsi_conn_start, 906 .stop_conn = iscsi_sw_tcp_conn_stop, 907 /* iscsi host params */ 908 .get_host_param = iscsi_host_get_param, 909 .set_host_param = iscsi_host_set_param, 910 /* IO */ 911 .send_pdu = iscsi_conn_send_pdu, 912 .get_stats = iscsi_sw_tcp_conn_get_stats, 913 /* iscsi task/cmd helpers */ 914 .init_task = iscsi_tcp_task_init, 915 .xmit_task = iscsi_tcp_task_xmit, 916 .cleanup_task = iscsi_tcp_cleanup_task, 917 /* low level pdu helpers */ 918 .xmit_pdu = iscsi_sw_tcp_pdu_xmit, 919 .init_pdu = iscsi_sw_tcp_pdu_init, 920 .alloc_pdu = iscsi_sw_tcp_pdu_alloc, 921 /* recovery */ 922 .session_recovery_timedout = iscsi_session_recovery_timedout, 923 }; 924 925 static int __init iscsi_sw_tcp_init(void) 926 { 927 if (iscsi_max_lun < 1) { 928 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n", 929 iscsi_max_lun); 930 return -EINVAL; 931 } 932 933 iscsi_sw_tcp_scsi_transport = iscsi_register_transport( 934 &iscsi_sw_tcp_transport); 935 if (!iscsi_sw_tcp_scsi_transport) 936 return -ENODEV; 937 938 return 0; 939 } 940 941 static void __exit iscsi_sw_tcp_exit(void) 942 { 943 iscsi_unregister_transport(&iscsi_sw_tcp_transport); 944 } 945 946 module_init(iscsi_sw_tcp_init); 947 module_exit(iscsi_sw_tcp_exit); 948