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 if (copied || r == -EAGAIN) 257 break; 258 return r; 259 } 260 copied += r; 261 } 262 return copied; 263 } 264 265 /** 266 * iscsi_sw_tcp_xmit - TCP transmit 267 **/ 268 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn) 269 { 270 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 271 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 272 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 273 unsigned int consumed = 0; 274 int rc = 0; 275 276 while (1) { 277 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment); 278 if (rc < 0) { 279 rc = ISCSI_ERR_XMIT_FAILED; 280 goto error; 281 } 282 if (rc == 0) 283 break; 284 285 consumed += rc; 286 287 if (segment->total_copied >= segment->total_size) { 288 if (segment->done != NULL) { 289 rc = segment->done(tcp_conn, segment); 290 if (rc != 0) 291 goto error; 292 } 293 } 294 } 295 296 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed); 297 298 conn->txdata_octets += consumed; 299 return consumed; 300 301 error: 302 /* Transmit error. We could initiate error recovery 303 * here. */ 304 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc); 305 iscsi_conn_failure(conn, rc); 306 return -EIO; 307 } 308 309 /** 310 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit 311 */ 312 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn) 313 { 314 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 315 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 316 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 317 318 return segment->total_copied - segment->total_size; 319 } 320 321 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task) 322 { 323 struct iscsi_conn *conn = task->conn; 324 int rc; 325 326 while (iscsi_sw_tcp_xmit_qlen(conn)) { 327 rc = iscsi_sw_tcp_xmit(conn); 328 if (rc == 0) 329 return -EAGAIN; 330 if (rc < 0) 331 return rc; 332 } 333 334 return 0; 335 } 336 337 /* 338 * This is called when we're done sending the header. 339 * Simply copy the data_segment to the send segment, and return. 340 */ 341 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn, 342 struct iscsi_segment *segment) 343 { 344 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 345 346 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment; 347 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn, 348 "Header done. Next segment size %u total_size %u\n", 349 tcp_sw_conn->out.segment.size, 350 tcp_sw_conn->out.segment.total_size); 351 return 0; 352 } 353 354 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, 355 size_t hdrlen) 356 { 357 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 358 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 359 360 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ? 361 "digest enabled" : "digest disabled"); 362 363 /* Clear the data segment - needs to be filled in by the 364 * caller using iscsi_tcp_send_data_prep() */ 365 memset(&tcp_sw_conn->out.data_segment, 0, 366 sizeof(struct iscsi_segment)); 367 368 /* If header digest is enabled, compute the CRC and 369 * place the digest into the same buffer. We make 370 * sure that both iscsi_tcp_task and mtask have 371 * sufficient room. 372 */ 373 if (conn->hdrdgst_en) { 374 iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen, 375 hdr + hdrlen); 376 hdrlen += ISCSI_DIGEST_SIZE; 377 } 378 379 /* Remember header pointer for later, when we need 380 * to decide whether there's a payload to go along 381 * with the header. */ 382 tcp_sw_conn->out.hdr = hdr; 383 384 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen, 385 iscsi_sw_tcp_send_hdr_done, NULL); 386 } 387 388 /* 389 * Prepare the send buffer for the payload data. 390 * Padding and checksumming will all be taken care 391 * of by the iscsi_segment routines. 392 */ 393 static int 394 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg, 395 unsigned int count, unsigned int offset, 396 unsigned int len) 397 { 398 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 399 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 400 struct hash_desc *tx_hash = NULL; 401 unsigned int hdr_spec_len; 402 403 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len, 404 conn->datadgst_en ? 405 "digest enabled" : "digest disabled"); 406 407 /* Make sure the datalen matches what the caller 408 said he would send. */ 409 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 410 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 411 412 if (conn->datadgst_en) 413 tx_hash = &tcp_sw_conn->tx_hash; 414 415 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment, 416 sg, count, offset, len, 417 NULL, tx_hash); 418 } 419 420 static void 421 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data, 422 size_t len) 423 { 424 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 425 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 426 struct hash_desc *tx_hash = NULL; 427 unsigned int hdr_spec_len; 428 429 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ? 430 "digest enabled" : "digest disabled"); 431 432 /* Make sure the datalen matches what the caller 433 said he would send. */ 434 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 435 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 436 437 if (conn->datadgst_en) 438 tx_hash = &tcp_sw_conn->tx_hash; 439 440 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment, 441 data, len, NULL, tx_hash); 442 } 443 444 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task, 445 unsigned int offset, unsigned int count) 446 { 447 struct iscsi_conn *conn = task->conn; 448 int err = 0; 449 450 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len); 451 452 if (!count) 453 return 0; 454 455 if (!task->sc) 456 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count); 457 else { 458 struct scsi_data_buffer *sdb = scsi_out(task->sc); 459 460 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl, 461 sdb->table.nents, offset, 462 count); 463 } 464 465 if (err) { 466 /* got invalid offset/len */ 467 return -EIO; 468 } 469 return 0; 470 } 471 472 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 473 { 474 struct iscsi_tcp_task *tcp_task = task->dd_data; 475 476 task->hdr = task->dd_data + sizeof(*tcp_task); 477 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE; 478 return 0; 479 } 480 481 static struct iscsi_cls_conn * 482 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session, 483 uint32_t conn_idx) 484 { 485 struct iscsi_conn *conn; 486 struct iscsi_cls_conn *cls_conn; 487 struct iscsi_tcp_conn *tcp_conn; 488 struct iscsi_sw_tcp_conn *tcp_sw_conn; 489 490 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn), 491 conn_idx); 492 if (!cls_conn) 493 return NULL; 494 conn = cls_conn->dd_data; 495 tcp_conn = conn->dd_data; 496 tcp_sw_conn = tcp_conn->dd_data; 497 498 tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0, 499 CRYPTO_ALG_ASYNC); 500 tcp_sw_conn->tx_hash.flags = 0; 501 if (IS_ERR(tcp_sw_conn->tx_hash.tfm)) 502 goto free_conn; 503 504 tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0, 505 CRYPTO_ALG_ASYNC); 506 tcp_sw_conn->rx_hash.flags = 0; 507 if (IS_ERR(tcp_sw_conn->rx_hash.tfm)) 508 goto free_tx_tfm; 509 tcp_conn->rx_hash = &tcp_sw_conn->rx_hash; 510 511 return cls_conn; 512 513 free_tx_tfm: 514 crypto_free_hash(tcp_sw_conn->tx_hash.tfm); 515 free_conn: 516 iscsi_conn_printk(KERN_ERR, conn, 517 "Could not create connection due to crc32c " 518 "loading error. Make sure the crc32c " 519 "module is built as a module or into the " 520 "kernel\n"); 521 iscsi_tcp_conn_teardown(cls_conn); 522 return NULL; 523 } 524 525 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn) 526 { 527 struct iscsi_session *session = conn->session; 528 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 529 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 530 struct socket *sock = tcp_sw_conn->sock; 531 532 if (!sock) 533 return; 534 535 sock_hold(sock->sk); 536 iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn); 537 sock_put(sock->sk); 538 539 spin_lock_bh(&session->lock); 540 tcp_sw_conn->sock = NULL; 541 spin_unlock_bh(&session->lock); 542 sockfd_put(sock); 543 } 544 545 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn) 546 { 547 struct iscsi_conn *conn = cls_conn->dd_data; 548 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 549 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 550 551 iscsi_sw_tcp_release_conn(conn); 552 553 if (tcp_sw_conn->tx_hash.tfm) 554 crypto_free_hash(tcp_sw_conn->tx_hash.tfm); 555 if (tcp_sw_conn->rx_hash.tfm) 556 crypto_free_hash(tcp_sw_conn->rx_hash.tfm); 557 558 iscsi_tcp_conn_teardown(cls_conn); 559 } 560 561 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 562 { 563 struct iscsi_conn *conn = cls_conn->dd_data; 564 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 565 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 566 567 /* userspace may have goofed up and not bound us */ 568 if (!tcp_sw_conn->sock) 569 return; 570 /* 571 * Make sure our recv side is stopped. 572 * Older tools called conn stop before ep_disconnect 573 * so IO could still be coming in. 574 */ 575 write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock); 576 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); 577 write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock); 578 579 iscsi_conn_stop(cls_conn, flag); 580 iscsi_sw_tcp_release_conn(conn); 581 } 582 583 static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock, 584 char *buf, int *port, 585 int (*getname)(struct socket *, 586 struct sockaddr *, 587 int *addrlen)) 588 { 589 struct sockaddr_storage *addr; 590 struct sockaddr_in6 *sin6; 591 struct sockaddr_in *sin; 592 int rc = 0, len; 593 594 addr = kmalloc(sizeof(*addr), GFP_KERNEL); 595 if (!addr) 596 return -ENOMEM; 597 598 if (getname(sock, (struct sockaddr *) addr, &len)) { 599 rc = -ENODEV; 600 goto free_addr; 601 } 602 603 switch (addr->ss_family) { 604 case AF_INET: 605 sin = (struct sockaddr_in *)addr; 606 spin_lock_bh(&conn->session->lock); 607 sprintf(buf, "%pI4", &sin->sin_addr.s_addr); 608 *port = be16_to_cpu(sin->sin_port); 609 spin_unlock_bh(&conn->session->lock); 610 break; 611 case AF_INET6: 612 sin6 = (struct sockaddr_in6 *)addr; 613 spin_lock_bh(&conn->session->lock); 614 sprintf(buf, "%pI6", &sin6->sin6_addr); 615 *port = be16_to_cpu(sin6->sin6_port); 616 spin_unlock_bh(&conn->session->lock); 617 break; 618 } 619 free_addr: 620 kfree(addr); 621 return rc; 622 } 623 624 static int 625 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session, 626 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph, 627 int is_leading) 628 { 629 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 630 struct iscsi_host *ihost = shost_priv(shost); 631 struct iscsi_conn *conn = cls_conn->dd_data; 632 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 633 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 634 struct sock *sk; 635 struct socket *sock; 636 int err; 637 638 /* lookup for existing socket */ 639 sock = sockfd_lookup((int)transport_eph, &err); 640 if (!sock) { 641 iscsi_conn_printk(KERN_ERR, conn, 642 "sockfd_lookup failed %d\n", err); 643 return -EEXIST; 644 } 645 /* 646 * copy these values now because if we drop the session 647 * userspace may still want to query the values since we will 648 * be using them for the reconnect 649 */ 650 err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address, 651 &conn->portal_port, kernel_getpeername); 652 if (err) 653 goto free_socket; 654 655 err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address, 656 &ihost->local_port, kernel_getsockname); 657 if (err) 658 goto free_socket; 659 660 err = iscsi_conn_bind(cls_session, cls_conn, is_leading); 661 if (err) 662 goto free_socket; 663 664 /* bind iSCSI connection and socket */ 665 tcp_sw_conn->sock = sock; 666 667 /* setup Socket parameters */ 668 sk = sock->sk; 669 sk->sk_reuse = 1; 670 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */ 671 sk->sk_allocation = GFP_ATOMIC; 672 673 iscsi_sw_tcp_conn_set_callbacks(conn); 674 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage; 675 /* 676 * set receive state machine into initial state 677 */ 678 iscsi_tcp_hdr_recv_prep(tcp_conn); 679 return 0; 680 681 free_socket: 682 sockfd_put(sock); 683 return err; 684 } 685 686 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn, 687 enum iscsi_param param, char *buf, 688 int buflen) 689 { 690 struct iscsi_conn *conn = cls_conn->dd_data; 691 struct iscsi_session *session = conn->session; 692 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 693 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 694 int value; 695 696 switch(param) { 697 case ISCSI_PARAM_HDRDGST_EN: 698 iscsi_set_param(cls_conn, param, buf, buflen); 699 break; 700 case ISCSI_PARAM_DATADGST_EN: 701 iscsi_set_param(cls_conn, param, buf, buflen); 702 tcp_sw_conn->sendpage = conn->datadgst_en ? 703 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; 704 break; 705 case ISCSI_PARAM_MAX_R2T: 706 sscanf(buf, "%d", &value); 707 if (value <= 0 || !is_power_of_2(value)) 708 return -EINVAL; 709 if (session->max_r2t == value) 710 break; 711 iscsi_tcp_r2tpool_free(session); 712 iscsi_set_param(cls_conn, param, buf, buflen); 713 if (iscsi_tcp_r2tpool_alloc(session)) 714 return -ENOMEM; 715 break; 716 default: 717 return iscsi_set_param(cls_conn, param, buf, buflen); 718 } 719 720 return 0; 721 } 722 723 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn, 724 enum iscsi_param param, char *buf) 725 { 726 struct iscsi_conn *conn = cls_conn->dd_data; 727 int len; 728 729 switch(param) { 730 case ISCSI_PARAM_CONN_PORT: 731 spin_lock_bh(&conn->session->lock); 732 len = sprintf(buf, "%hu\n", conn->portal_port); 733 spin_unlock_bh(&conn->session->lock); 734 break; 735 case ISCSI_PARAM_CONN_ADDRESS: 736 spin_lock_bh(&conn->session->lock); 737 len = sprintf(buf, "%s\n", conn->portal_address); 738 spin_unlock_bh(&conn->session->lock); 739 break; 740 default: 741 return iscsi_conn_get_param(cls_conn, param, buf); 742 } 743 744 return len; 745 } 746 747 static void 748 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, 749 struct iscsi_stats *stats) 750 { 751 struct iscsi_conn *conn = cls_conn->dd_data; 752 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 753 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 754 755 stats->custom_length = 3; 756 strcpy(stats->custom[0].desc, "tx_sendpage_failures"); 757 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt; 758 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr"); 759 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt; 760 strcpy(stats->custom[2].desc, "eh_abort_cnt"); 761 stats->custom[2].value = conn->eh_abort_cnt; 762 763 iscsi_tcp_conn_get_stats(cls_conn, stats); 764 } 765 766 static struct iscsi_cls_session * 767 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max, 768 uint16_t qdepth, uint32_t initial_cmdsn) 769 { 770 struct iscsi_cls_session *cls_session; 771 struct iscsi_session *session; 772 struct Scsi_Host *shost; 773 774 if (ep) { 775 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep); 776 return NULL; 777 } 778 779 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, 1); 780 if (!shost) 781 return NULL; 782 shost->transportt = iscsi_sw_tcp_scsi_transport; 783 shost->cmd_per_lun = qdepth; 784 shost->max_lun = iscsi_max_lun; 785 shost->max_id = 0; 786 shost->max_channel = 0; 787 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE; 788 789 if (iscsi_host_add(shost, NULL)) 790 goto free_host; 791 792 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost, 793 cmds_max, 794 sizeof(struct iscsi_tcp_task) + 795 sizeof(struct iscsi_sw_tcp_hdrbuf), 796 initial_cmdsn, 0); 797 if (!cls_session) 798 goto remove_host; 799 session = cls_session->dd_data; 800 801 shost->can_queue = session->scsi_cmds_max; 802 if (iscsi_tcp_r2tpool_alloc(session)) 803 goto remove_session; 804 return cls_session; 805 806 remove_session: 807 iscsi_session_teardown(cls_session); 808 remove_host: 809 iscsi_host_remove(shost); 810 free_host: 811 iscsi_host_free(shost); 812 return NULL; 813 } 814 815 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session) 816 { 817 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 818 819 iscsi_tcp_r2tpool_free(cls_session->dd_data); 820 iscsi_session_teardown(cls_session); 821 822 iscsi_host_remove(shost); 823 iscsi_host_free(shost); 824 } 825 826 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev) 827 { 828 set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags); 829 return 0; 830 } 831 832 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev) 833 { 834 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY); 835 blk_queue_dma_alignment(sdev->request_queue, 0); 836 return 0; 837 } 838 839 static struct scsi_host_template iscsi_sw_tcp_sht = { 840 .module = THIS_MODULE, 841 .name = "iSCSI Initiator over TCP/IP", 842 .queuecommand = iscsi_queuecommand, 843 .change_queue_depth = iscsi_change_queue_depth, 844 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1, 845 .sg_tablesize = 4096, 846 .max_sectors = 0xFFFF, 847 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN, 848 .eh_abort_handler = iscsi_eh_abort, 849 .eh_device_reset_handler= iscsi_eh_device_reset, 850 .eh_target_reset_handler= iscsi_eh_target_reset, 851 .use_clustering = DISABLE_CLUSTERING, 852 .slave_alloc = iscsi_sw_tcp_slave_alloc, 853 .slave_configure = iscsi_sw_tcp_slave_configure, 854 .target_alloc = iscsi_target_alloc, 855 .proc_name = "iscsi_tcp", 856 .this_id = -1, 857 }; 858 859 static struct iscsi_transport iscsi_sw_tcp_transport = { 860 .owner = THIS_MODULE, 861 .name = "tcp", 862 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST 863 | CAP_DATADGST, 864 .param_mask = ISCSI_MAX_RECV_DLENGTH | 865 ISCSI_MAX_XMIT_DLENGTH | 866 ISCSI_HDRDGST_EN | 867 ISCSI_DATADGST_EN | 868 ISCSI_INITIAL_R2T_EN | 869 ISCSI_MAX_R2T | 870 ISCSI_IMM_DATA_EN | 871 ISCSI_FIRST_BURST | 872 ISCSI_MAX_BURST | 873 ISCSI_PDU_INORDER_EN | 874 ISCSI_DATASEQ_INORDER_EN | 875 ISCSI_ERL | 876 ISCSI_CONN_PORT | 877 ISCSI_CONN_ADDRESS | 878 ISCSI_EXP_STATSN | 879 ISCSI_PERSISTENT_PORT | 880 ISCSI_PERSISTENT_ADDRESS | 881 ISCSI_TARGET_NAME | ISCSI_TPGT | 882 ISCSI_USERNAME | ISCSI_PASSWORD | 883 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN | 884 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO | 885 ISCSI_LU_RESET_TMO | 886 ISCSI_PING_TMO | ISCSI_RECV_TMO | 887 ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME, 888 .host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS | 889 ISCSI_HOST_INITIATOR_NAME | 890 ISCSI_HOST_NETDEV_NAME, 891 /* session management */ 892 .create_session = iscsi_sw_tcp_session_create, 893 .destroy_session = iscsi_sw_tcp_session_destroy, 894 /* connection management */ 895 .create_conn = iscsi_sw_tcp_conn_create, 896 .bind_conn = iscsi_sw_tcp_conn_bind, 897 .destroy_conn = iscsi_sw_tcp_conn_destroy, 898 .set_param = iscsi_sw_tcp_conn_set_param, 899 .get_conn_param = iscsi_sw_tcp_conn_get_param, 900 .get_session_param = iscsi_session_get_param, 901 .start_conn = iscsi_conn_start, 902 .stop_conn = iscsi_sw_tcp_conn_stop, 903 /* iscsi host params */ 904 .get_host_param = iscsi_host_get_param, 905 .set_host_param = iscsi_host_set_param, 906 /* IO */ 907 .send_pdu = iscsi_conn_send_pdu, 908 .get_stats = iscsi_sw_tcp_conn_get_stats, 909 /* iscsi task/cmd helpers */ 910 .init_task = iscsi_tcp_task_init, 911 .xmit_task = iscsi_tcp_task_xmit, 912 .cleanup_task = iscsi_tcp_cleanup_task, 913 /* low level pdu helpers */ 914 .xmit_pdu = iscsi_sw_tcp_pdu_xmit, 915 .init_pdu = iscsi_sw_tcp_pdu_init, 916 .alloc_pdu = iscsi_sw_tcp_pdu_alloc, 917 /* recovery */ 918 .session_recovery_timedout = iscsi_session_recovery_timedout, 919 }; 920 921 static int __init iscsi_sw_tcp_init(void) 922 { 923 if (iscsi_max_lun < 1) { 924 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n", 925 iscsi_max_lun); 926 return -EINVAL; 927 } 928 929 iscsi_sw_tcp_scsi_transport = iscsi_register_transport( 930 &iscsi_sw_tcp_transport); 931 if (!iscsi_sw_tcp_scsi_transport) 932 return -ENODEV; 933 934 return 0; 935 } 936 937 static void __exit iscsi_sw_tcp_exit(void) 938 { 939 iscsi_unregister_transport(&iscsi_sw_tcp_transport); 940 } 941 942 module_init(iscsi_sw_tcp_init); 943 module_exit(iscsi_sw_tcp_exit); 944