1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * iSCSI Initiator over TCP/IP Data-Path 4 * 5 * Copyright (C) 2004 Dmitry Yusupov 6 * Copyright (C) 2004 Alex Aizman 7 * Copyright (C) 2005 - 2006 Mike Christie 8 * Copyright (C) 2006 Red Hat, Inc. All rights reserved. 9 * maintained by open-iscsi@googlegroups.com 10 * 11 * See the file COPYING included with this distribution for more details. 12 * 13 * Credits: 14 * Christoph Hellwig 15 * FUJITA Tomonori 16 * Arne Redlich 17 * Zhenyu Wang 18 */ 19 20 #include <crypto/hash.h> 21 #include <linux/types.h> 22 #include <linux/inet.h> 23 #include <linux/slab.h> 24 #include <linux/sched/mm.h> 25 #include <linux/file.h> 26 #include <linux/blkdev.h> 27 #include <linux/delay.h> 28 #include <linux/kfifo.h> 29 #include <linux/scatterlist.h> 30 #include <linux/module.h> 31 #include <linux/backing-dev.h> 32 #include <net/tcp.h> 33 #include <scsi/scsi_cmnd.h> 34 #include <scsi/scsi_device.h> 35 #include <scsi/scsi_host.h> 36 #include <scsi/scsi.h> 37 #include <scsi/scsi_transport_iscsi.h> 38 #include <trace/events/iscsi.h> 39 40 #include "iscsi_tcp.h" 41 42 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, " 43 "Dmitry Yusupov <dmitry_yus@yahoo.com>, " 44 "Alex Aizman <itn780@yahoo.com>"); 45 MODULE_DESCRIPTION("iSCSI/TCP data-path"); 46 MODULE_LICENSE("GPL"); 47 48 static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport; 49 static struct scsi_host_template iscsi_sw_tcp_sht; 50 static struct iscsi_transport iscsi_sw_tcp_transport; 51 52 static unsigned int iscsi_max_lun = ~0; 53 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO); 54 55 static int iscsi_sw_tcp_dbg; 56 module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int, 57 S_IRUGO | S_IWUSR); 58 MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module " 59 "Set to 1 to turn on, and zero to turn off. Default is off."); 60 61 #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \ 62 do { \ 63 if (iscsi_sw_tcp_dbg) \ 64 iscsi_conn_printk(KERN_INFO, _conn, \ 65 "%s " dbg_fmt, \ 66 __func__, ##arg); \ 67 iscsi_dbg_trace(trace_iscsi_dbg_sw_tcp, \ 68 &(_conn)->cls_conn->dev, \ 69 "%s " dbg_fmt, __func__, ##arg);\ 70 } while (0); 71 72 73 /** 74 * iscsi_sw_tcp_recv - TCP receive in sendfile fashion 75 * @rd_desc: read descriptor 76 * @skb: socket buffer 77 * @offset: offset in skb 78 * @len: skb->len - offset 79 */ 80 static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, 81 unsigned int offset, size_t len) 82 { 83 struct iscsi_conn *conn = rd_desc->arg.data; 84 unsigned int consumed, total_consumed = 0; 85 int status; 86 87 ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset); 88 89 do { 90 status = 0; 91 consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status); 92 offset += consumed; 93 total_consumed += consumed; 94 } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE); 95 96 ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n", 97 skb->len - offset, status); 98 return total_consumed; 99 } 100 101 /** 102 * iscsi_sw_sk_state_check - check socket state 103 * @sk: socket 104 * 105 * If the socket is in CLOSE or CLOSE_WAIT we should 106 * not close the connection if there is still some 107 * data pending. 108 * 109 * Must be called with sk_callback_lock. 110 */ 111 static inline int iscsi_sw_sk_state_check(struct sock *sk) 112 { 113 struct iscsi_conn *conn = sk->sk_user_data; 114 115 if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) && 116 (conn->session->state != ISCSI_STATE_LOGGING_OUT) && 117 !atomic_read(&sk->sk_rmem_alloc)) { 118 ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n"); 119 iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE); 120 return -ECONNRESET; 121 } 122 return 0; 123 } 124 125 static void iscsi_sw_tcp_data_ready(struct sock *sk) 126 { 127 struct iscsi_conn *conn; 128 struct iscsi_tcp_conn *tcp_conn; 129 read_descriptor_t rd_desc; 130 131 read_lock_bh(&sk->sk_callback_lock); 132 conn = sk->sk_user_data; 133 if (!conn) { 134 read_unlock_bh(&sk->sk_callback_lock); 135 return; 136 } 137 tcp_conn = conn->dd_data; 138 139 /* 140 * Use rd_desc to pass 'conn' to iscsi_tcp_recv. 141 * We set count to 1 because we want the network layer to 142 * hand us all the skbs that are available. iscsi_tcp_recv 143 * handled pdus that cross buffers or pdus that still need data. 144 */ 145 rd_desc.arg.data = conn; 146 rd_desc.count = 1; 147 tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv); 148 149 iscsi_sw_sk_state_check(sk); 150 151 /* If we had to (atomically) map a highmem page, 152 * unmap it now. */ 153 iscsi_tcp_segment_unmap(&tcp_conn->in.segment); 154 read_unlock_bh(&sk->sk_callback_lock); 155 } 156 157 static void iscsi_sw_tcp_state_change(struct sock *sk) 158 { 159 struct iscsi_tcp_conn *tcp_conn; 160 struct iscsi_sw_tcp_conn *tcp_sw_conn; 161 struct iscsi_conn *conn; 162 void (*old_state_change)(struct sock *); 163 164 read_lock_bh(&sk->sk_callback_lock); 165 conn = sk->sk_user_data; 166 if (!conn) { 167 read_unlock_bh(&sk->sk_callback_lock); 168 return; 169 } 170 171 iscsi_sw_sk_state_check(sk); 172 173 tcp_conn = conn->dd_data; 174 tcp_sw_conn = tcp_conn->dd_data; 175 old_state_change = tcp_sw_conn->old_state_change; 176 177 read_unlock_bh(&sk->sk_callback_lock); 178 179 old_state_change(sk); 180 } 181 182 /** 183 * iscsi_sw_tcp_write_space - Called when more output buffer space is available 184 * @sk: socket space is available for 185 **/ 186 static void iscsi_sw_tcp_write_space(struct sock *sk) 187 { 188 struct iscsi_conn *conn; 189 struct iscsi_tcp_conn *tcp_conn; 190 struct iscsi_sw_tcp_conn *tcp_sw_conn; 191 void (*old_write_space)(struct sock *); 192 193 read_lock_bh(&sk->sk_callback_lock); 194 conn = sk->sk_user_data; 195 if (!conn) { 196 read_unlock_bh(&sk->sk_callback_lock); 197 return; 198 } 199 200 tcp_conn = conn->dd_data; 201 tcp_sw_conn = tcp_conn->dd_data; 202 old_write_space = tcp_sw_conn->old_write_space; 203 read_unlock_bh(&sk->sk_callback_lock); 204 205 old_write_space(sk); 206 207 ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n"); 208 iscsi_conn_queue_work(conn); 209 } 210 211 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn) 212 { 213 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 214 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 215 struct sock *sk = tcp_sw_conn->sock->sk; 216 217 /* assign new callbacks */ 218 write_lock_bh(&sk->sk_callback_lock); 219 sk->sk_user_data = conn; 220 tcp_sw_conn->old_data_ready = sk->sk_data_ready; 221 tcp_sw_conn->old_state_change = sk->sk_state_change; 222 tcp_sw_conn->old_write_space = sk->sk_write_space; 223 sk->sk_data_ready = iscsi_sw_tcp_data_ready; 224 sk->sk_state_change = iscsi_sw_tcp_state_change; 225 sk->sk_write_space = iscsi_sw_tcp_write_space; 226 write_unlock_bh(&sk->sk_callback_lock); 227 } 228 229 static void 230 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn *conn) 231 { 232 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 233 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 234 struct sock *sk = tcp_sw_conn->sock->sk; 235 236 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */ 237 write_lock_bh(&sk->sk_callback_lock); 238 sk->sk_user_data = NULL; 239 sk->sk_data_ready = tcp_sw_conn->old_data_ready; 240 sk->sk_state_change = tcp_sw_conn->old_state_change; 241 sk->sk_write_space = tcp_sw_conn->old_write_space; 242 sk->sk_no_check_tx = 0; 243 write_unlock_bh(&sk->sk_callback_lock); 244 } 245 246 /** 247 * iscsi_sw_tcp_xmit_segment - transmit segment 248 * @tcp_conn: the iSCSI TCP connection 249 * @segment: the buffer to transmnit 250 * 251 * This function transmits as much of the buffer as 252 * the network layer will accept, and returns the number of 253 * bytes transmitted. 254 * 255 * If CRC hashing is enabled, the function will compute the 256 * hash as it goes. When the entire segment has been transmitted, 257 * it will retrieve the hash value and send it as well. 258 */ 259 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn, 260 struct iscsi_segment *segment) 261 { 262 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 263 struct socket *sk = tcp_sw_conn->sock; 264 unsigned int copied = 0; 265 int r = 0; 266 267 while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) { 268 struct scatterlist *sg; 269 unsigned int offset, copy; 270 int flags = 0; 271 272 r = 0; 273 offset = segment->copied; 274 copy = segment->size - offset; 275 276 if (segment->total_copied + segment->size < segment->total_size) 277 flags |= MSG_MORE; 278 279 /* Use sendpage if we can; else fall back to sendmsg */ 280 if (!segment->data) { 281 sg = segment->sg; 282 offset += segment->sg_offset + sg->offset; 283 r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset, 284 copy, flags); 285 } else { 286 struct msghdr msg = { .msg_flags = flags }; 287 struct kvec iov = { 288 .iov_base = segment->data + offset, 289 .iov_len = copy 290 }; 291 292 r = kernel_sendmsg(sk, &msg, &iov, 1, copy); 293 } 294 295 if (r < 0) { 296 iscsi_tcp_segment_unmap(segment); 297 return r; 298 } 299 copied += r; 300 } 301 return copied; 302 } 303 304 /** 305 * iscsi_sw_tcp_xmit - TCP transmit 306 * @conn: iscsi connection 307 **/ 308 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn) 309 { 310 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 311 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 312 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 313 unsigned int consumed = 0; 314 int rc = 0; 315 316 while (1) { 317 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment); 318 /* 319 * We may not have been able to send data because the conn 320 * is getting stopped. libiscsi will know so propagate err 321 * for it to do the right thing. 322 */ 323 if (rc == -EAGAIN) 324 return rc; 325 else if (rc < 0) { 326 rc = ISCSI_ERR_XMIT_FAILED; 327 goto error; 328 } else if (rc == 0) 329 break; 330 331 consumed += rc; 332 333 if (segment->total_copied >= segment->total_size) { 334 if (segment->done != NULL) { 335 rc = segment->done(tcp_conn, segment); 336 if (rc != 0) 337 goto error; 338 } 339 } 340 } 341 342 ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed); 343 344 conn->txdata_octets += consumed; 345 return consumed; 346 347 error: 348 /* Transmit error. We could initiate error recovery 349 * here. */ 350 ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc); 351 iscsi_conn_failure(conn, rc); 352 return -EIO; 353 } 354 355 /** 356 * iscsi_sw_tcp_xmit_qlen - return the number of bytes queued for xmit 357 * @conn: iscsi connection 358 */ 359 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn) 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 struct iscsi_segment *segment = &tcp_sw_conn->out.segment; 364 365 return segment->total_copied - segment->total_size; 366 } 367 368 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task) 369 { 370 struct iscsi_conn *conn = task->conn; 371 unsigned int noreclaim_flag; 372 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 373 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 374 int rc = 0; 375 376 if (!tcp_sw_conn->sock) { 377 iscsi_conn_printk(KERN_ERR, conn, 378 "Transport not bound to socket!\n"); 379 return -EINVAL; 380 } 381 382 noreclaim_flag = memalloc_noreclaim_save(); 383 384 while (iscsi_sw_tcp_xmit_qlen(conn)) { 385 rc = iscsi_sw_tcp_xmit(conn); 386 if (rc == 0) { 387 rc = -EAGAIN; 388 break; 389 } 390 if (rc < 0) 391 break; 392 rc = 0; 393 } 394 395 memalloc_noreclaim_restore(noreclaim_flag); 396 return rc; 397 } 398 399 /* 400 * This is called when we're done sending the header. 401 * Simply copy the data_segment to the send segment, and return. 402 */ 403 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn, 404 struct iscsi_segment *segment) 405 { 406 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 407 408 tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment; 409 ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn, 410 "Header done. Next segment size %u total_size %u\n", 411 tcp_sw_conn->out.segment.size, 412 tcp_sw_conn->out.segment.total_size); 413 return 0; 414 } 415 416 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, 417 size_t hdrlen) 418 { 419 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 420 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 421 422 ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ? 423 "digest enabled" : "digest disabled"); 424 425 /* Clear the data segment - needs to be filled in by the 426 * caller using iscsi_tcp_send_data_prep() */ 427 memset(&tcp_sw_conn->out.data_segment, 0, 428 sizeof(struct iscsi_segment)); 429 430 /* If header digest is enabled, compute the CRC and 431 * place the digest into the same buffer. We make 432 * sure that both iscsi_tcp_task and mtask have 433 * sufficient room. 434 */ 435 if (conn->hdrdgst_en) { 436 iscsi_tcp_dgst_header(tcp_sw_conn->tx_hash, hdr, hdrlen, 437 hdr + hdrlen); 438 hdrlen += ISCSI_DIGEST_SIZE; 439 } 440 441 /* Remember header pointer for later, when we need 442 * to decide whether there's a payload to go along 443 * with the header. */ 444 tcp_sw_conn->out.hdr = hdr; 445 446 iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen, 447 iscsi_sw_tcp_send_hdr_done, NULL); 448 } 449 450 /* 451 * Prepare the send buffer for the payload data. 452 * Padding and checksumming will all be taken care 453 * of by the iscsi_segment routines. 454 */ 455 static int 456 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg, 457 unsigned int count, unsigned int offset, 458 unsigned int len) 459 { 460 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 461 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 462 struct ahash_request *tx_hash = NULL; 463 unsigned int hdr_spec_len; 464 465 ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len, 466 conn->datadgst_en ? 467 "digest enabled" : "digest disabled"); 468 469 /* Make sure the datalen matches what the caller 470 said he would send. */ 471 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 472 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 473 474 if (conn->datadgst_en) 475 tx_hash = tcp_sw_conn->tx_hash; 476 477 return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment, 478 sg, count, offset, len, 479 NULL, tx_hash); 480 } 481 482 static void 483 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data, 484 size_t len) 485 { 486 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 487 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 488 struct ahash_request *tx_hash = NULL; 489 unsigned int hdr_spec_len; 490 491 ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ? 492 "digest enabled" : "digest disabled"); 493 494 /* Make sure the datalen matches what the caller 495 said he would send. */ 496 hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); 497 WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); 498 499 if (conn->datadgst_en) 500 tx_hash = tcp_sw_conn->tx_hash; 501 502 iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment, 503 data, len, NULL, tx_hash); 504 } 505 506 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task, 507 unsigned int offset, unsigned int count) 508 { 509 struct iscsi_conn *conn = task->conn; 510 int err = 0; 511 512 iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len); 513 514 if (!count) 515 return 0; 516 517 if (!task->sc) 518 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count); 519 else { 520 struct scsi_data_buffer *sdb = &task->sc->sdb; 521 522 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl, 523 sdb->table.nents, offset, 524 count); 525 } 526 527 if (err) { 528 /* got invalid offset/len */ 529 return -EIO; 530 } 531 return 0; 532 } 533 534 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode) 535 { 536 struct iscsi_tcp_task *tcp_task = task->dd_data; 537 538 task->hdr = task->dd_data + sizeof(*tcp_task); 539 task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE; 540 return 0; 541 } 542 543 static struct iscsi_cls_conn * 544 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session, 545 uint32_t conn_idx) 546 { 547 struct iscsi_conn *conn; 548 struct iscsi_cls_conn *cls_conn; 549 struct iscsi_tcp_conn *tcp_conn; 550 struct iscsi_sw_tcp_conn *tcp_sw_conn; 551 struct crypto_ahash *tfm; 552 553 cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn), 554 conn_idx); 555 if (!cls_conn) 556 return NULL; 557 conn = cls_conn->dd_data; 558 tcp_conn = conn->dd_data; 559 tcp_sw_conn = tcp_conn->dd_data; 560 561 tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC); 562 if (IS_ERR(tfm)) 563 goto free_conn; 564 565 tcp_sw_conn->tx_hash = ahash_request_alloc(tfm, GFP_KERNEL); 566 if (!tcp_sw_conn->tx_hash) 567 goto free_tfm; 568 ahash_request_set_callback(tcp_sw_conn->tx_hash, 0, NULL, NULL); 569 570 tcp_sw_conn->rx_hash = ahash_request_alloc(tfm, GFP_KERNEL); 571 if (!tcp_sw_conn->rx_hash) 572 goto free_tx_hash; 573 ahash_request_set_callback(tcp_sw_conn->rx_hash, 0, NULL, NULL); 574 575 tcp_conn->rx_hash = tcp_sw_conn->rx_hash; 576 577 return cls_conn; 578 579 free_tx_hash: 580 ahash_request_free(tcp_sw_conn->tx_hash); 581 free_tfm: 582 crypto_free_ahash(tfm); 583 free_conn: 584 iscsi_conn_printk(KERN_ERR, conn, 585 "Could not create connection due to crc32c " 586 "loading error. Make sure the crc32c " 587 "module is built as a module or into the " 588 "kernel\n"); 589 iscsi_tcp_conn_teardown(cls_conn); 590 return NULL; 591 } 592 593 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn) 594 { 595 struct iscsi_session *session = conn->session; 596 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 597 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 598 struct socket *sock = tcp_sw_conn->sock; 599 600 if (!sock) 601 return; 602 603 /* 604 * Make sure we start socket shutdown now in case userspace is up 605 * but delayed in releasing the socket. 606 */ 607 kernel_sock_shutdown(sock, SHUT_RDWR); 608 609 sock_hold(sock->sk); 610 iscsi_sw_tcp_conn_restore_callbacks(conn); 611 sock_put(sock->sk); 612 613 spin_lock_bh(&session->frwd_lock); 614 tcp_sw_conn->sock = NULL; 615 spin_unlock_bh(&session->frwd_lock); 616 sockfd_put(sock); 617 } 618 619 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn) 620 { 621 struct iscsi_conn *conn = cls_conn->dd_data; 622 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 623 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 624 625 iscsi_sw_tcp_release_conn(conn); 626 627 ahash_request_free(tcp_sw_conn->rx_hash); 628 if (tcp_sw_conn->tx_hash) { 629 struct crypto_ahash *tfm; 630 631 tfm = crypto_ahash_reqtfm(tcp_sw_conn->tx_hash); 632 ahash_request_free(tcp_sw_conn->tx_hash); 633 crypto_free_ahash(tfm); 634 } 635 636 iscsi_tcp_conn_teardown(cls_conn); 637 } 638 639 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) 640 { 641 struct iscsi_conn *conn = cls_conn->dd_data; 642 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 643 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 644 struct socket *sock = tcp_sw_conn->sock; 645 646 /* userspace may have goofed up and not bound us */ 647 if (!sock) 648 return; 649 650 sock->sk->sk_err = EIO; 651 wake_up_interruptible(sk_sleep(sock->sk)); 652 653 /* stop xmit side */ 654 iscsi_suspend_tx(conn); 655 656 /* stop recv side and release socket */ 657 iscsi_sw_tcp_release_conn(conn); 658 659 iscsi_conn_stop(cls_conn, flag); 660 } 661 662 static int 663 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session, 664 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph, 665 int is_leading) 666 { 667 struct iscsi_session *session = cls_session->dd_data; 668 struct iscsi_conn *conn = cls_conn->dd_data; 669 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 670 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 671 struct sock *sk; 672 struct socket *sock; 673 int err; 674 675 /* lookup for existing socket */ 676 sock = sockfd_lookup((int)transport_eph, &err); 677 if (!sock) { 678 iscsi_conn_printk(KERN_ERR, conn, 679 "sockfd_lookup failed %d\n", err); 680 return -EEXIST; 681 } 682 683 err = iscsi_conn_bind(cls_session, cls_conn, is_leading); 684 if (err) 685 goto free_socket; 686 687 spin_lock_bh(&session->frwd_lock); 688 /* bind iSCSI connection and socket */ 689 tcp_sw_conn->sock = sock; 690 spin_unlock_bh(&session->frwd_lock); 691 692 /* setup Socket parameters */ 693 sk = sock->sk; 694 sk->sk_reuse = SK_CAN_REUSE; 695 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */ 696 sk->sk_allocation = GFP_ATOMIC; 697 sk_set_memalloc(sk); 698 sock_no_linger(sk); 699 700 iscsi_sw_tcp_conn_set_callbacks(conn); 701 tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage; 702 /* 703 * set receive state machine into initial state 704 */ 705 iscsi_tcp_hdr_recv_prep(tcp_conn); 706 return 0; 707 708 free_socket: 709 sockfd_put(sock); 710 return err; 711 } 712 713 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn, 714 enum iscsi_param param, char *buf, 715 int buflen) 716 { 717 struct iscsi_conn *conn = cls_conn->dd_data; 718 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 719 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 720 721 switch(param) { 722 case ISCSI_PARAM_HDRDGST_EN: 723 iscsi_set_param(cls_conn, param, buf, buflen); 724 break; 725 case ISCSI_PARAM_DATADGST_EN: 726 iscsi_set_param(cls_conn, param, buf, buflen); 727 tcp_sw_conn->sendpage = conn->datadgst_en ? 728 sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; 729 break; 730 case ISCSI_PARAM_MAX_R2T: 731 return iscsi_tcp_set_max_r2t(conn, buf); 732 default: 733 return iscsi_set_param(cls_conn, param, buf, buflen); 734 } 735 736 return 0; 737 } 738 739 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn, 740 enum iscsi_param param, char *buf) 741 { 742 struct iscsi_conn *conn = cls_conn->dd_data; 743 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 744 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 745 struct sockaddr_in6 addr; 746 struct socket *sock; 747 int rc; 748 749 switch(param) { 750 case ISCSI_PARAM_CONN_PORT: 751 case ISCSI_PARAM_CONN_ADDRESS: 752 case ISCSI_PARAM_LOCAL_PORT: 753 spin_lock_bh(&conn->session->frwd_lock); 754 if (!tcp_sw_conn || !tcp_sw_conn->sock) { 755 spin_unlock_bh(&conn->session->frwd_lock); 756 return -ENOTCONN; 757 } 758 sock = tcp_sw_conn->sock; 759 sock_hold(sock->sk); 760 spin_unlock_bh(&conn->session->frwd_lock); 761 762 if (param == ISCSI_PARAM_LOCAL_PORT) 763 rc = kernel_getsockname(sock, 764 (struct sockaddr *)&addr); 765 else 766 rc = kernel_getpeername(sock, 767 (struct sockaddr *)&addr); 768 sock_put(sock->sk); 769 if (rc < 0) 770 return rc; 771 772 return iscsi_conn_get_addr_param((struct sockaddr_storage *) 773 &addr, param, buf); 774 default: 775 return iscsi_conn_get_param(cls_conn, param, buf); 776 } 777 778 return 0; 779 } 780 781 static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost, 782 enum iscsi_host_param param, char *buf) 783 { 784 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost); 785 struct iscsi_session *session = tcp_sw_host->session; 786 struct iscsi_conn *conn; 787 struct iscsi_tcp_conn *tcp_conn; 788 struct iscsi_sw_tcp_conn *tcp_sw_conn; 789 struct sockaddr_in6 addr; 790 struct socket *sock; 791 int rc; 792 793 switch (param) { 794 case ISCSI_HOST_PARAM_IPADDRESS: 795 if (!session) 796 return -ENOTCONN; 797 798 spin_lock_bh(&session->frwd_lock); 799 conn = session->leadconn; 800 if (!conn) { 801 spin_unlock_bh(&session->frwd_lock); 802 return -ENOTCONN; 803 } 804 tcp_conn = conn->dd_data; 805 tcp_sw_conn = tcp_conn->dd_data; 806 sock = tcp_sw_conn->sock; 807 if (!sock) { 808 spin_unlock_bh(&session->frwd_lock); 809 return -ENOTCONN; 810 } 811 sock_hold(sock->sk); 812 spin_unlock_bh(&session->frwd_lock); 813 814 rc = kernel_getsockname(sock, 815 (struct sockaddr *)&addr); 816 sock_put(sock->sk); 817 if (rc < 0) 818 return rc; 819 820 return iscsi_conn_get_addr_param((struct sockaddr_storage *) 821 &addr, 822 (enum iscsi_param)param, buf); 823 default: 824 return iscsi_host_get_param(shost, param, buf); 825 } 826 827 return 0; 828 } 829 830 static void 831 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, 832 struct iscsi_stats *stats) 833 { 834 struct iscsi_conn *conn = cls_conn->dd_data; 835 struct iscsi_tcp_conn *tcp_conn = conn->dd_data; 836 struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; 837 838 stats->custom_length = 3; 839 strcpy(stats->custom[0].desc, "tx_sendpage_failures"); 840 stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt; 841 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr"); 842 stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt; 843 strcpy(stats->custom[2].desc, "eh_abort_cnt"); 844 stats->custom[2].value = conn->eh_abort_cnt; 845 846 iscsi_tcp_conn_get_stats(cls_conn, stats); 847 } 848 849 static struct iscsi_cls_session * 850 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max, 851 uint16_t qdepth, uint32_t initial_cmdsn) 852 { 853 struct iscsi_cls_session *cls_session; 854 struct iscsi_session *session; 855 struct iscsi_sw_tcp_host *tcp_sw_host; 856 struct Scsi_Host *shost; 857 int rc; 858 859 if (ep) { 860 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep); 861 return NULL; 862 } 863 864 shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 865 sizeof(struct iscsi_sw_tcp_host), 1); 866 if (!shost) 867 return NULL; 868 shost->transportt = iscsi_sw_tcp_scsi_transport; 869 shost->cmd_per_lun = qdepth; 870 shost->max_lun = iscsi_max_lun; 871 shost->max_id = 0; 872 shost->max_channel = 0; 873 shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE; 874 875 rc = iscsi_host_get_max_scsi_cmds(shost, cmds_max); 876 if (rc < 0) 877 goto free_host; 878 shost->can_queue = rc; 879 880 if (iscsi_host_add(shost, NULL)) 881 goto free_host; 882 883 cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost, 884 cmds_max, 0, 885 sizeof(struct iscsi_tcp_task) + 886 sizeof(struct iscsi_sw_tcp_hdrbuf), 887 initial_cmdsn, 0); 888 if (!cls_session) 889 goto remove_host; 890 session = cls_session->dd_data; 891 tcp_sw_host = iscsi_host_priv(shost); 892 tcp_sw_host->session = session; 893 894 if (iscsi_tcp_r2tpool_alloc(session)) 895 goto remove_session; 896 return cls_session; 897 898 remove_session: 899 iscsi_session_teardown(cls_session); 900 remove_host: 901 iscsi_host_remove(shost); 902 free_host: 903 iscsi_host_free(shost); 904 return NULL; 905 } 906 907 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session) 908 { 909 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); 910 struct iscsi_session *session = cls_session->dd_data; 911 912 if (WARN_ON_ONCE(session->leadconn)) 913 return; 914 915 iscsi_tcp_r2tpool_free(cls_session->dd_data); 916 iscsi_session_teardown(cls_session); 917 918 iscsi_host_remove(shost); 919 iscsi_host_free(shost); 920 } 921 922 static umode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param) 923 { 924 switch (param_type) { 925 case ISCSI_HOST_PARAM: 926 switch (param) { 927 case ISCSI_HOST_PARAM_NETDEV_NAME: 928 case ISCSI_HOST_PARAM_HWADDRESS: 929 case ISCSI_HOST_PARAM_IPADDRESS: 930 case ISCSI_HOST_PARAM_INITIATOR_NAME: 931 return S_IRUGO; 932 default: 933 return 0; 934 } 935 case ISCSI_PARAM: 936 switch (param) { 937 case ISCSI_PARAM_MAX_RECV_DLENGTH: 938 case ISCSI_PARAM_MAX_XMIT_DLENGTH: 939 case ISCSI_PARAM_HDRDGST_EN: 940 case ISCSI_PARAM_DATADGST_EN: 941 case ISCSI_PARAM_CONN_ADDRESS: 942 case ISCSI_PARAM_CONN_PORT: 943 case ISCSI_PARAM_LOCAL_PORT: 944 case ISCSI_PARAM_EXP_STATSN: 945 case ISCSI_PARAM_PERSISTENT_ADDRESS: 946 case ISCSI_PARAM_PERSISTENT_PORT: 947 case ISCSI_PARAM_PING_TMO: 948 case ISCSI_PARAM_RECV_TMO: 949 case ISCSI_PARAM_INITIAL_R2T_EN: 950 case ISCSI_PARAM_MAX_R2T: 951 case ISCSI_PARAM_IMM_DATA_EN: 952 case ISCSI_PARAM_FIRST_BURST: 953 case ISCSI_PARAM_MAX_BURST: 954 case ISCSI_PARAM_PDU_INORDER_EN: 955 case ISCSI_PARAM_DATASEQ_INORDER_EN: 956 case ISCSI_PARAM_ERL: 957 case ISCSI_PARAM_TARGET_NAME: 958 case ISCSI_PARAM_TPGT: 959 case ISCSI_PARAM_USERNAME: 960 case ISCSI_PARAM_PASSWORD: 961 case ISCSI_PARAM_USERNAME_IN: 962 case ISCSI_PARAM_PASSWORD_IN: 963 case ISCSI_PARAM_FAST_ABORT: 964 case ISCSI_PARAM_ABORT_TMO: 965 case ISCSI_PARAM_LU_RESET_TMO: 966 case ISCSI_PARAM_TGT_RESET_TMO: 967 case ISCSI_PARAM_IFACE_NAME: 968 case ISCSI_PARAM_INITIATOR_NAME: 969 return S_IRUGO; 970 default: 971 return 0; 972 } 973 } 974 975 return 0; 976 } 977 978 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev) 979 { 980 struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(sdev->host); 981 struct iscsi_session *session = tcp_sw_host->session; 982 struct iscsi_conn *conn = session->leadconn; 983 984 if (conn->datadgst_en) 985 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, 986 sdev->request_queue); 987 blk_queue_dma_alignment(sdev->request_queue, 0); 988 return 0; 989 } 990 991 static struct scsi_host_template iscsi_sw_tcp_sht = { 992 .module = THIS_MODULE, 993 .name = "iSCSI Initiator over TCP/IP", 994 .queuecommand = iscsi_queuecommand, 995 .change_queue_depth = scsi_change_queue_depth, 996 .can_queue = ISCSI_TOTAL_CMDS_MAX, 997 .sg_tablesize = 4096, 998 .max_sectors = 0xFFFF, 999 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN, 1000 .eh_timed_out = iscsi_eh_cmd_timed_out, 1001 .eh_abort_handler = iscsi_eh_abort, 1002 .eh_device_reset_handler= iscsi_eh_device_reset, 1003 .eh_target_reset_handler = iscsi_eh_recover_target, 1004 .dma_boundary = PAGE_SIZE - 1, 1005 .slave_configure = iscsi_sw_tcp_slave_configure, 1006 .target_alloc = iscsi_target_alloc, 1007 .proc_name = "iscsi_tcp", 1008 .this_id = -1, 1009 .track_queue_depth = 1, 1010 .cmd_size = sizeof(struct iscsi_cmd), 1011 }; 1012 1013 static struct iscsi_transport iscsi_sw_tcp_transport = { 1014 .owner = THIS_MODULE, 1015 .name = "tcp", 1016 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST 1017 | CAP_DATADGST, 1018 /* session management */ 1019 .create_session = iscsi_sw_tcp_session_create, 1020 .destroy_session = iscsi_sw_tcp_session_destroy, 1021 /* connection management */ 1022 .create_conn = iscsi_sw_tcp_conn_create, 1023 .bind_conn = iscsi_sw_tcp_conn_bind, 1024 .destroy_conn = iscsi_sw_tcp_conn_destroy, 1025 .attr_is_visible = iscsi_sw_tcp_attr_is_visible, 1026 .set_param = iscsi_sw_tcp_conn_set_param, 1027 .get_conn_param = iscsi_sw_tcp_conn_get_param, 1028 .get_session_param = iscsi_session_get_param, 1029 .start_conn = iscsi_conn_start, 1030 .stop_conn = iscsi_sw_tcp_conn_stop, 1031 /* iscsi host params */ 1032 .get_host_param = iscsi_sw_tcp_host_get_param, 1033 .set_host_param = iscsi_host_set_param, 1034 /* IO */ 1035 .send_pdu = iscsi_conn_send_pdu, 1036 .get_stats = iscsi_sw_tcp_conn_get_stats, 1037 /* iscsi task/cmd helpers */ 1038 .init_task = iscsi_tcp_task_init, 1039 .xmit_task = iscsi_tcp_task_xmit, 1040 .cleanup_task = iscsi_tcp_cleanup_task, 1041 /* low level pdu helpers */ 1042 .xmit_pdu = iscsi_sw_tcp_pdu_xmit, 1043 .init_pdu = iscsi_sw_tcp_pdu_init, 1044 .alloc_pdu = iscsi_sw_tcp_pdu_alloc, 1045 /* recovery */ 1046 .session_recovery_timedout = iscsi_session_recovery_timedout, 1047 }; 1048 1049 static int __init iscsi_sw_tcp_init(void) 1050 { 1051 if (iscsi_max_lun < 1) { 1052 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n", 1053 iscsi_max_lun); 1054 return -EINVAL; 1055 } 1056 1057 iscsi_sw_tcp_scsi_transport = iscsi_register_transport( 1058 &iscsi_sw_tcp_transport); 1059 if (!iscsi_sw_tcp_scsi_transport) 1060 return -ENODEV; 1061 1062 return 0; 1063 } 1064 1065 static void __exit iscsi_sw_tcp_exit(void) 1066 { 1067 iscsi_unregister_transport(&iscsi_sw_tcp_transport); 1068 } 1069 1070 module_init(iscsi_sw_tcp_init); 1071 module_exit(iscsi_sw_tcp_exit); 1072