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 /** 103 * iscsi_sw_sk_state_check - check socket state 104 * @sk: socket 105 * 106 * If the socket is in CLOSE or CLOSE_WAIT we should 107 * not close the connection if there is still some 108 * data pending. 109 */ 110 static inline int iscsi_sw_sk_state_check(struct sock *sk) 111 { 112 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data; 113 114 if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) && 115 !atomic_read(&sk->sk_rmem_alloc)) { 116 ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n"); 117 iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE); 118 return -ECONNRESET; 119 } 120 return 0; 121 } 122 123 static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag) 124 { 125 struct iscsi_conn *conn = sk->sk_user_data; 126 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 127 read_descriptor_t rd_desc; 128 129 read_lock(&sk->sk_callback_lock); 130 131 /* 132 * Use rd_desc to pass 'conn' to iscsi_tcp_recv. 133 * We set count to 1 because we want the network layer to 134 * hand us all the skbs that are available. iscsi_tcp_recv 135 * handled pdus that cross buffers or pdus that still need data. 136 */ 137 rd_desc.arg.data = conn; 138 rd_desc.count = 1; 139 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv); 140 141 iscsi_sw_sk_state_check(sk); 142 143 read_unlock(&sk->sk_callback_lock); 144 145 /* If we had to (atomically) map a highmem page, 146 * unmap it now. */ 147 iscsi_tcp_segment_unmap(&tcp_conn->in.segment); 148 } 149 150 static void iscsi_sw_tcp_state_change(struct sock *sk) 151 { 152 struct iscsi_tcp_conn *tcp_conn; 153 struct iscsi_sw_tcp_conn *tcp_sw_conn; 154 struct iscsi_conn *conn; 155 struct iscsi_session *session; 156 void (*old_state_change)(struct sock *); 157 158 read_lock(&sk->sk_callback_lock); 159 160 conn = (struct iscsi_conn*)sk->sk_user_data; 161 session = conn->session; 162 163 iscsi_sw_sk_state_check(sk); 164 165 tcp_conn = conn->dd_data; 166 tcp_sw_conn = tcp_conn->dd_data; 167 old_state_change = tcp_sw_conn->old_state_change; 168 169 read_unlock(&sk->sk_callback_lock); 170 171 old_state_change(sk); 172 } 173 174 /** 175 * iscsi_write_space - Called when more output buffer space is available 176 * @sk: socket space is available for 177 **/ 178 static void iscsi_sw_tcp_write_space(struct sock *sk) 179 { 180 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data; 181 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 182 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 183 184 tcp_sw_conn->old_write_space(sk); 185 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n"); 186 iscsi_conn_queue_work(conn); 187 } 188 189 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn) 190 { 191 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 192 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 193 struct sock *sk = tcp_sw_conn->sock->sk; 194 195 /* assign new callbacks */ 196 write_lock_bh(&sk->sk_callback_lock); 197 sk->sk_user_data = conn; 198 tcp_sw_conn->old_data_ready = sk->sk_data_ready; 199 tcp_sw_conn->old_state_change = sk->sk_state_change; 200 tcp_sw_conn->old_write_space = sk->sk_write_space; 201 sk->sk_data_ready = iscsi_sw_tcp_data_ready; 202 sk->sk_state_change = iscsi_sw_tcp_state_change; 203 sk->sk_write_space = iscsi_sw_tcp_write_space; 204 write_unlock_bh(&sk->sk_callback_lock); 205 } 206 207 static void 208 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn) 209 { 210 struct sock *sk = tcp_sw_conn->sock->sk; 211 212 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */ 213 write_lock_bh(&sk->sk_callback_lock); 214 sk->sk_user_data = NULL; 215 sk->sk_data_ready = tcp_sw_conn->old_data_ready; 216 sk->sk_state_change = tcp_sw_conn->old_state_change; 217 sk->sk_write_space = tcp_sw_conn->old_write_space; 218 sk->sk_no_check = 0; 219 write_unlock_bh(&sk->sk_callback_lock); 220 } 221 222 /** 223 * iscsi_sw_tcp_xmit_segment - transmit segment 224 * @tcp_conn: the iSCSI TCP connection 225 * @segment: the buffer to transmnit 226 * 227 * This function transmits as much of the buffer as 228 * the network layer will accept, and returns the number of 229 * bytes transmitted. 230 * 231 * If CRC hashing is enabled, the function will compute the 232 * hash as it goes. When the entire segment has been transmitted, 233 * it will retrieve the hash value and send it as well. 234 */ 235 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn, 236 struct iscsi_segment *segment) 237 { 238 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 239 struct socket *sk = tcp_sw_conn->sock; 240 unsigned int copied = 0; 241 int r = 0; 242 243 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) { 244 struct scatterlist *sg; 245 unsigned int offset, copy; 246 int flags = 0; 247 248 r = 0; 249 offset = segment->copied; 250 copy = segment->size - offset; 251 252 if (segment->total_copied + segment->size < segment->total_size) 253 flags |= MSG_MORE; 254 255 /* Use sendpage if we can; else fall back to sendmsg */ 256 if (!segment->data) { 257 sg = segment->sg; 258 offset += segment->sg_offset + sg->offset; 259 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset, 260 copy, flags); 261 } else { 262 struct msghdr msg = { .msg_flags = flags }; 263 struct kvec iov = { 264 .iov_base = segment->data + offset, 265 .iov_len = copy 266 }; 267 268 r = kernel_sendmsg(sk, &msg, &iov, 1, copy); 269 } 270 271 if (r < 0) { 272 iscsi_tcp_segment_unmap(segment); 273 return r; 274 } 275 copied += r; 276 } 277 return copied; 278 } 279 280 /** 281 * iscsi_sw_tcp_xmit - TCP transmit 282 **/ 283 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn) 284 { 285 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 286 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 287 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 288 unsigned int consumed = 0; 289 int rc = 0; 290 291 while (1) { 292 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment); 293 /* 294 * We may not have been able to send data because the conn 295 * is getting stopped. libiscsi will know so propogate err 296 * for it to do the right thing. 297 */ 298 if (rc == -EAGAIN) 299 return rc; 300 else if (rc < 0) { 301 rc = ISCSI_ERR_XMIT_FAILED; 302 goto error; 303 } else if (rc == 0) 304 break; 305 306 consumed += rc; 307 308 if (segment->total_copied >= segment->total_size) { 309 if (segment->done != NULL) { 310 rc = segment->done(tcp_conn, segment); 311 if (rc != 0) 312 goto error; 313 } 314 } 315 } 316 317 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed); 318 319 conn->txdata_octets += consumed; 320 return consumed; 321 322 error: 323 /* Transmit error. We could initiate error recovery 324 * here. */ 325 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc); 326 iscsi_conn_failure(conn, rc); 327 return -EIO; 328 } 329 330 /** 331 * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit 332 */ 333 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn) 334 { 335 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 336 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 337 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 338 339 return segment->total_copied - segment->total_size; 340 } 341 342 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task) 343 { 344 struct iscsi_conn *conn = task->conn; 345 int rc; 346 347 while (iscsi_sw_tcp_xmit_qlen(conn)) { 348 rc = iscsi_sw_tcp_xmit(conn); 349 if (rc == 0) 350 return -EAGAIN; 351 if (rc < 0) 352 return rc; 353 } 354 355 return 0; 356 } 357 358 /* 359 * This is called when we're done sending the header. 360 * Simply copy the data_segment to the send segment, and return. 361 */ 362 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn, 363 struct iscsi_segment *segment) 364 { 365 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 366 367 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment; 368 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn, 369 "Header done. Next segment size %u total_size %u\n", 370 tcp_sw_conn->out.segment.size, 371 tcp_sw_conn->out.segment.total_size); 372 return 0; 373 } 374 375 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, 376 size_t hdrlen) 377 { 378 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 379 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 380 381 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ? 382 "digest enabled" : "digest disabled"); 383 384 /* Clear the data segment - needs to be filled in by the 385 * caller using iscsi_tcp_send_data_prep() */ 386 memset(&tcp_sw_conn->out.data_segment, 0, 387 sizeof(struct iscsi_segment)); 388 389 /* If header digest is enabled, compute the CRC and 390 * place the digest into the same buffer. We make 391 * sure that both iscsi_tcp_task and mtask have 392 * sufficient room. 393 */ 394 if (conn->hdrdgst_en) { 395 iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen, 396 hdr + hdrlen); 397 hdrlen += ISCSI_DIGEST_SIZE; 398 } 399 400 /* Remember header pointer for later, when we need 401 * to decide whether there's a payload to go along 402 * with the header. */ 403 tcp_sw_conn->out.hdr = hdr; 404 405 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen, 406 iscsi_sw_tcp_send_hdr_done, NULL); 407 } 408 409 /* 410 * Prepare the send buffer for the payload data. 411 * Padding and checksumming will all be taken care 412 * of by the iscsi_segment routines. 413 */ 414 static int 415 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg, 416 unsigned int count, unsigned int offset, 417 unsigned int len) 418 { 419 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 420 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 421 struct hash_desc *tx_hash = NULL; 422 unsigned int hdr_spec_len; 423 424 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len, 425 conn->datadgst_en ? 426 "digest enabled" : "digest disabled"); 427 428 /* Make sure the datalen matches what the caller 429 said he would send. */ 430 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 431 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 432 433 if (conn->datadgst_en) 434 tx_hash = &tcp_sw_conn->tx_hash; 435 436 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment, 437 sg, count, offset, len, 438 NULL, tx_hash); 439 } 440 441 static void 442 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data, 443 size_t len) 444 { 445 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 446 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 447 struct hash_desc *tx_hash = NULL; 448 unsigned int hdr_spec_len; 449 450 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ? 451 "digest enabled" : "digest disabled"); 452 453 /* Make sure the datalen matches what the caller 454 said he would send. */ 455 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 456 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 457 458 if (conn->datadgst_en) 459 tx_hash = &tcp_sw_conn->tx_hash; 460 461 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment, 462 data, len, NULL, tx_hash); 463 } 464 465 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task, 466 unsigned int offset, unsigned int count) 467 { 468 struct iscsi_conn *conn = task->conn; 469 int err = 0; 470 471 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len); 472 473 if (!count) 474 return 0; 475 476 if (!task->sc) 477 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count); 478 else { 479 struct scsi_data_buffer *sdb = scsi_out(task->sc); 480 481 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl, 482 sdb->table.nents, offset, 483 count); 484 } 485 486 if (err) { 487 /* got invalid offset/len */ 488 return -EIO; 489 } 490 return 0; 491 } 492 493 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 494 { 495 struct iscsi_tcp_task *tcp_task = task->dd_data; 496 497 task->hdr = task->dd_data + sizeof(*tcp_task); 498 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE; 499 return 0; 500 } 501 502 static struct iscsi_cls_conn * 503 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session, 504 uint32_t conn_idx) 505 { 506 struct iscsi_conn *conn; 507 struct iscsi_cls_conn *cls_conn; 508 struct iscsi_tcp_conn *tcp_conn; 509 struct iscsi_sw_tcp_conn *tcp_sw_conn; 510 511 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn), 512 conn_idx); 513 if (!cls_conn) 514 return NULL; 515 conn = cls_conn->dd_data; 516 tcp_conn = conn->dd_data; 517 tcp_sw_conn = tcp_conn->dd_data; 518 519 tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0, 520 CRYPTO_ALG_ASYNC); 521 tcp_sw_conn->tx_hash.flags = 0; 522 if (IS_ERR(tcp_sw_conn->tx_hash.tfm)) 523 goto free_conn; 524 525 tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0, 526 CRYPTO_ALG_ASYNC); 527 tcp_sw_conn->rx_hash.flags = 0; 528 if (IS_ERR(tcp_sw_conn->rx_hash.tfm)) 529 goto free_tx_tfm; 530 tcp_conn->rx_hash = &tcp_sw_conn->rx_hash; 531 532 return cls_conn; 533 534 free_tx_tfm: 535 crypto_free_hash(tcp_sw_conn->tx_hash.tfm); 536 free_conn: 537 iscsi_conn_printk(KERN_ERR, conn, 538 "Could not create connection due to crc32c " 539 "loading error. Make sure the crc32c " 540 "module is built as a module or into the " 541 "kernel\n"); 542 iscsi_tcp_conn_teardown(cls_conn); 543 return NULL; 544 } 545 546 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn) 547 { 548 struct iscsi_session *session = conn->session; 549 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 550 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 551 struct socket *sock = tcp_sw_conn->sock; 552 553 if (!sock) 554 return; 555 556 sock_hold(sock->sk); 557 iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn); 558 sock_put(sock->sk); 559 560 spin_lock_bh(&session->lock); 561 tcp_sw_conn->sock = NULL; 562 spin_unlock_bh(&session->lock); 563 sockfd_put(sock); 564 } 565 566 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn) 567 { 568 struct iscsi_conn *conn = cls_conn->dd_data; 569 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 570 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 571 572 iscsi_sw_tcp_release_conn(conn); 573 574 if (tcp_sw_conn->tx_hash.tfm) 575 crypto_free_hash(tcp_sw_conn->tx_hash.tfm); 576 if (tcp_sw_conn->rx_hash.tfm) 577 crypto_free_hash(tcp_sw_conn->rx_hash.tfm); 578 579 iscsi_tcp_conn_teardown(cls_conn); 580 } 581 582 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 583 { 584 struct iscsi_conn *conn = cls_conn->dd_data; 585 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 586 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 587 588 /* userspace may have goofed up and not bound us */ 589 if (!tcp_sw_conn->sock) 590 return; 591 /* 592 * Make sure our recv side is stopped. 593 * Older tools called conn stop before ep_disconnect 594 * so IO could still be coming in. 595 */ 596 write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock); 597 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); 598 write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock); 599 600 iscsi_conn_stop(cls_conn, flag); 601 iscsi_sw_tcp_release_conn(conn); 602 } 603 604 static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock, 605 char *buf, int *port, 606 int (*getname)(struct socket *, 607 struct sockaddr *, 608 int *addrlen)) 609 { 610 struct sockaddr_storage *addr; 611 struct sockaddr_in6 *sin6; 612 struct sockaddr_in *sin; 613 int rc = 0, len; 614 615 addr = kmalloc(sizeof(*addr), GFP_KERNEL); 616 if (!addr) 617 return -ENOMEM; 618 619 if (getname(sock, (struct sockaddr *) addr, &len)) { 620 rc = -ENODEV; 621 goto free_addr; 622 } 623 624 switch (addr->ss_family) { 625 case AF_INET: 626 sin = (struct sockaddr_in *)addr; 627 spin_lock_bh(&conn->session->lock); 628 sprintf(buf, "%pI4", &sin->sin_addr.s_addr); 629 *port = be16_to_cpu(sin->sin_port); 630 spin_unlock_bh(&conn->session->lock); 631 break; 632 case AF_INET6: 633 sin6 = (struct sockaddr_in6 *)addr; 634 spin_lock_bh(&conn->session->lock); 635 sprintf(buf, "%pI6", &sin6->sin6_addr); 636 *port = be16_to_cpu(sin6->sin6_port); 637 spin_unlock_bh(&conn->session->lock); 638 break; 639 } 640 free_addr: 641 kfree(addr); 642 return rc; 643 } 644 645 static int 646 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session, 647 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph, 648 int is_leading) 649 { 650 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 651 struct iscsi_host *ihost = shost_priv(shost); 652 struct iscsi_conn *conn = cls_conn->dd_data; 653 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 654 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 655 struct sock *sk; 656 struct socket *sock; 657 int err; 658 659 /* lookup for existing socket */ 660 sock = sockfd_lookup((int)transport_eph, &err); 661 if (!sock) { 662 iscsi_conn_printk(KERN_ERR, conn, 663 "sockfd_lookup failed %d\n", err); 664 return -EEXIST; 665 } 666 /* 667 * copy these values now because if we drop the session 668 * userspace may still want to query the values since we will 669 * be using them for the reconnect 670 */ 671 err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address, 672 &conn->portal_port, kernel_getpeername); 673 if (err) 674 goto free_socket; 675 676 err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address, 677 &ihost->local_port, kernel_getsockname); 678 if (err) 679 goto free_socket; 680 681 err = iscsi_conn_bind(cls_session, cls_conn, is_leading); 682 if (err) 683 goto free_socket; 684 685 /* bind iSCSI connection and socket */ 686 tcp_sw_conn->sock = sock; 687 688 /* setup Socket parameters */ 689 sk = sock->sk; 690 sk->sk_reuse = 1; 691 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */ 692 sk->sk_allocation = GFP_ATOMIC; 693 694 iscsi_sw_tcp_conn_set_callbacks(conn); 695 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage; 696 /* 697 * set receive state machine into initial state 698 */ 699 iscsi_tcp_hdr_recv_prep(tcp_conn); 700 return 0; 701 702 free_socket: 703 sockfd_put(sock); 704 return err; 705 } 706 707 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn, 708 enum iscsi_param param, char *buf, 709 int buflen) 710 { 711 struct iscsi_conn *conn = cls_conn->dd_data; 712 struct iscsi_session *session = conn->session; 713 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 714 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 715 int value; 716 717 switch(param) { 718 case ISCSI_PARAM_HDRDGST_EN: 719 iscsi_set_param(cls_conn, param, buf, buflen); 720 break; 721 case ISCSI_PARAM_DATADGST_EN: 722 iscsi_set_param(cls_conn, param, buf, buflen); 723 tcp_sw_conn->sendpage = conn->datadgst_en ? 724 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; 725 break; 726 case ISCSI_PARAM_MAX_R2T: 727 sscanf(buf, "%d", &value); 728 if (value <= 0 || !is_power_of_2(value)) 729 return -EINVAL; 730 if (session->max_r2t == value) 731 break; 732 iscsi_tcp_r2tpool_free(session); 733 iscsi_set_param(cls_conn, param, buf, buflen); 734 if (iscsi_tcp_r2tpool_alloc(session)) 735 return -ENOMEM; 736 break; 737 default: 738 return iscsi_set_param(cls_conn, param, buf, buflen); 739 } 740 741 return 0; 742 } 743 744 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn, 745 enum iscsi_param param, char *buf) 746 { 747 struct iscsi_conn *conn = cls_conn->dd_data; 748 int len; 749 750 switch(param) { 751 case ISCSI_PARAM_CONN_PORT: 752 spin_lock_bh(&conn->session->lock); 753 len = sprintf(buf, "%hu\n", conn->portal_port); 754 spin_unlock_bh(&conn->session->lock); 755 break; 756 case ISCSI_PARAM_CONN_ADDRESS: 757 spin_lock_bh(&conn->session->lock); 758 len = sprintf(buf, "%s\n", conn->portal_address); 759 spin_unlock_bh(&conn->session->lock); 760 break; 761 default: 762 return iscsi_conn_get_param(cls_conn, param, buf); 763 } 764 765 return len; 766 } 767 768 static void 769 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, 770 struct iscsi_stats *stats) 771 { 772 struct iscsi_conn *conn = cls_conn->dd_data; 773 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 774 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 775 776 stats->custom_length = 3; 777 strcpy(stats->custom[0].desc, "tx_sendpage_failures"); 778 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt; 779 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr"); 780 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt; 781 strcpy(stats->custom[2].desc, "eh_abort_cnt"); 782 stats->custom[2].value = conn->eh_abort_cnt; 783 784 iscsi_tcp_conn_get_stats(cls_conn, stats); 785 } 786 787 static struct iscsi_cls_session * 788 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max, 789 uint16_t qdepth, uint32_t initial_cmdsn) 790 { 791 struct iscsi_cls_session *cls_session; 792 struct iscsi_session *session; 793 struct Scsi_Host *shost; 794 795 if (ep) { 796 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep); 797 return NULL; 798 } 799 800 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, 1); 801 if (!shost) 802 return NULL; 803 shost->transportt = iscsi_sw_tcp_scsi_transport; 804 shost->cmd_per_lun = qdepth; 805 shost->max_lun = iscsi_max_lun; 806 shost->max_id = 0; 807 shost->max_channel = 0; 808 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE; 809 810 if (iscsi_host_add(shost, NULL)) 811 goto free_host; 812 813 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost, 814 cmds_max, 0, 815 sizeof(struct iscsi_tcp_task) + 816 sizeof(struct iscsi_sw_tcp_hdrbuf), 817 initial_cmdsn, 0); 818 if (!cls_session) 819 goto remove_host; 820 session = cls_session->dd_data; 821 822 shost->can_queue = session->scsi_cmds_max; 823 if (iscsi_tcp_r2tpool_alloc(session)) 824 goto remove_session; 825 return cls_session; 826 827 remove_session: 828 iscsi_session_teardown(cls_session); 829 remove_host: 830 iscsi_host_remove(shost); 831 free_host: 832 iscsi_host_free(shost); 833 return NULL; 834 } 835 836 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session) 837 { 838 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 839 840 iscsi_tcp_r2tpool_free(cls_session->dd_data); 841 iscsi_session_teardown(cls_session); 842 843 iscsi_host_remove(shost); 844 iscsi_host_free(shost); 845 } 846 847 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev) 848 { 849 set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags); 850 return 0; 851 } 852 853 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev) 854 { 855 blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY); 856 blk_queue_dma_alignment(sdev->request_queue, 0); 857 return 0; 858 } 859 860 static struct scsi_host_template iscsi_sw_tcp_sht = { 861 .module = THIS_MODULE, 862 .name = "iSCSI Initiator over TCP/IP", 863 .queuecommand = iscsi_queuecommand, 864 .change_queue_depth = iscsi_change_queue_depth, 865 .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1, 866 .sg_tablesize = 4096, 867 .max_sectors = 0xFFFF, 868 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN, 869 .eh_abort_handler = iscsi_eh_abort, 870 .eh_device_reset_handler= iscsi_eh_device_reset, 871 .eh_target_reset_handler= iscsi_eh_target_reset, 872 .use_clustering = DISABLE_CLUSTERING, 873 .slave_alloc = iscsi_sw_tcp_slave_alloc, 874 .slave_configure = iscsi_sw_tcp_slave_configure, 875 .target_alloc = iscsi_target_alloc, 876 .proc_name = "iscsi_tcp", 877 .this_id = -1, 878 }; 879 880 static struct iscsi_transport iscsi_sw_tcp_transport = { 881 .owner = THIS_MODULE, 882 .name = "tcp", 883 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST 884 | CAP_DATADGST, 885 .param_mask = ISCSI_MAX_RECV_DLENGTH | 886 ISCSI_MAX_XMIT_DLENGTH | 887 ISCSI_HDRDGST_EN | 888 ISCSI_DATADGST_EN | 889 ISCSI_INITIAL_R2T_EN | 890 ISCSI_MAX_R2T | 891 ISCSI_IMM_DATA_EN | 892 ISCSI_FIRST_BURST | 893 ISCSI_MAX_BURST | 894 ISCSI_PDU_INORDER_EN | 895 ISCSI_DATASEQ_INORDER_EN | 896 ISCSI_ERL | 897 ISCSI_CONN_PORT | 898 ISCSI_CONN_ADDRESS | 899 ISCSI_EXP_STATSN | 900 ISCSI_PERSISTENT_PORT | 901 ISCSI_PERSISTENT_ADDRESS | 902 ISCSI_TARGET_NAME | ISCSI_TPGT | 903 ISCSI_USERNAME | ISCSI_PASSWORD | 904 ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN | 905 ISCSI_FAST_ABORT | ISCSI_ABORT_TMO | 906 ISCSI_LU_RESET_TMO | ISCSI_TGT_RESET_TMO | 907 ISCSI_PING_TMO | ISCSI_RECV_TMO | 908 ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME, 909 .host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS | 910 ISCSI_HOST_INITIATOR_NAME | 911 ISCSI_HOST_NETDEV_NAME, 912 /* session management */ 913 .create_session = iscsi_sw_tcp_session_create, 914 .destroy_session = iscsi_sw_tcp_session_destroy, 915 /* connection management */ 916 .create_conn = iscsi_sw_tcp_conn_create, 917 .bind_conn = iscsi_sw_tcp_conn_bind, 918 .destroy_conn = iscsi_sw_tcp_conn_destroy, 919 .set_param = iscsi_sw_tcp_conn_set_param, 920 .get_conn_param = iscsi_sw_tcp_conn_get_param, 921 .get_session_param = iscsi_session_get_param, 922 .start_conn = iscsi_conn_start, 923 .stop_conn = iscsi_sw_tcp_conn_stop, 924 /* iscsi host params */ 925 .get_host_param = iscsi_host_get_param, 926 .set_host_param = iscsi_host_set_param, 927 /* IO */ 928 .send_pdu = iscsi_conn_send_pdu, 929 .get_stats = iscsi_sw_tcp_conn_get_stats, 930 /* iscsi task/cmd helpers */ 931 .init_task = iscsi_tcp_task_init, 932 .xmit_task = iscsi_tcp_task_xmit, 933 .cleanup_task = iscsi_tcp_cleanup_task, 934 /* low level pdu helpers */ 935 .xmit_pdu = iscsi_sw_tcp_pdu_xmit, 936 .init_pdu = iscsi_sw_tcp_pdu_init, 937 .alloc_pdu = iscsi_sw_tcp_pdu_alloc, 938 /* recovery */ 939 .session_recovery_timedout = iscsi_session_recovery_timedout, 940 }; 941 942 static int __init iscsi_sw_tcp_init(void) 943 { 944 if (iscsi_max_lun < 1) { 945 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n", 946 iscsi_max_lun); 947 return -EINVAL; 948 } 949 950 iscsi_sw_tcp_scsi_transport = iscsi_register_transport( 951 &iscsi_sw_tcp_transport); 952 if (!iscsi_sw_tcp_scsi_transport) 953 return -ENODEV; 954 955 return 0; 956 } 957 958 static void __exit iscsi_sw_tcp_exit(void) 959 { 960 iscsi_unregister_transport(&iscsi_sw_tcp_transport); 961 } 962 963 module_init(iscsi_sw_tcp_init); 964 module_exit(iscsi_sw_tcp_exit); 965