| 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/slab.h> |
| 32 | #include <linux/file.h> |
| 33 | #include <linux/blkdev.h> |
| 34 | #include <linux/crypto.h> |
| 35 | #include <linux/delay.h> |
| 36 | #include <linux/kfifo.h> |
| 37 | #include <linux/scatterlist.h> |
| 38 | #include <linux/module.h> |
| 39 | #include <net/tcp.h> |
| 40 | #include <scsi/scsi_cmnd.h> |
| 41 | #include <scsi/scsi_device.h> |
| 42 | #include <scsi/scsi_host.h> |
| 43 | #include <scsi/scsi.h> |
| 44 | #include <scsi/scsi_transport_iscsi.h> |
| 45 | |
| 46 | #include "iscsi_tcp.h" |
| 47 | |
| 48 | MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, " |
| 49 | "Dmitry Yusupov <dmitry_yus@yahoo.com>, " |
| 50 | "Alex Aizman <itn780@yahoo.com>"); |
| 51 | MODULE_DESCRIPTION("iSCSI/TCP data-path"); |
| 52 | MODULE_LICENSE("GPL"); |
| 53 | |
| 54 | static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport; |
| 55 | static struct scsi_host_template iscsi_sw_tcp_sht; |
| 56 | static struct iscsi_transport iscsi_sw_tcp_transport; |
| 57 | |
| 58 | static unsigned int iscsi_max_lun = 512; |
| 59 | module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO); |
| 60 | |
| 61 | static int iscsi_sw_tcp_dbg; |
| 62 | module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int, |
| 63 | S_IRUGO | S_IWUSR); |
| 64 | MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module " |
| 65 | "Set to 1 to turn on, and zero to turn off. Default is off."); |
| 66 | |
| 67 | #define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \ |
| 68 | do { \ |
| 69 | if (iscsi_sw_tcp_dbg) \ |
| 70 | iscsi_conn_printk(KERN_INFO, _conn, \ |
| 71 | "%s " dbg_fmt, \ |
| 72 | __func__, ##arg); \ |
| 73 | } while (0); |
| 74 | |
| 75 | |
| 76 | /** |
| 77 | * iscsi_sw_tcp_recv - TCP receive in sendfile fashion |
| 78 | * @rd_desc: read descriptor |
| 79 | * @skb: socket buffer |
| 80 | * @offset: offset in skb |
| 81 | * @len: skb->len - offset |
| 82 | */ |
| 83 | static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb, |
| 84 | unsigned int offset, size_t len) |
| 85 | { |
| 86 | struct iscsi_conn *conn = rd_desc->arg.data; |
| 87 | unsigned int consumed, total_consumed = 0; |
| 88 | int status; |
| 89 | |
| 90 | ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset); |
| 91 | |
| 92 | do { |
| 93 | status = 0; |
| 94 | consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status); |
| 95 | offset += consumed; |
| 96 | total_consumed += consumed; |
| 97 | } while (consumed != 0 && status != ISCSI_TCP_SKB_DONE); |
| 98 | |
| 99 | ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n", |
| 100 | skb->len - offset, status); |
| 101 | return total_consumed; |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * iscsi_sw_sk_state_check - check socket state |
| 106 | * @sk: socket |
| 107 | * |
| 108 | * If the socket is in CLOSE or CLOSE_WAIT we should |
| 109 | * not close the connection if there is still some |
| 110 | * data pending. |
| 111 | * |
| 112 | * Must be called with sk_callback_lock. |
| 113 | */ |
| 114 | static inline int iscsi_sw_sk_state_check(struct sock *sk) |
| 115 | { |
| 116 | struct iscsi_conn *conn = sk->sk_user_data; |
| 117 | |
| 118 | if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) && |
| 119 | !atomic_read(&sk->sk_rmem_alloc)) { |
| 120 | ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n"); |
| 121 | iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE); |
| 122 | return -ECONNRESET; |
| 123 | } |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag) |
| 128 | { |
| 129 | struct iscsi_conn *conn; |
| 130 | struct iscsi_tcp_conn *tcp_conn; |
| 131 | read_descriptor_t rd_desc; |
| 132 | |
| 133 | read_lock(&sk->sk_callback_lock); |
| 134 | conn = sk->sk_user_data; |
| 135 | if (!conn) { |
| 136 | read_unlock(&sk->sk_callback_lock); |
| 137 | return; |
| 138 | } |
| 139 | tcp_conn = conn->dd_data; |
| 140 | |
| 141 | /* |
| 142 | * Use rd_desc to pass 'conn' to iscsi_tcp_recv. |
| 143 | * We set count to 1 because we want the network layer to |
| 144 | * hand us all the skbs that are available. iscsi_tcp_recv |
| 145 | * handled pdus that cross buffers or pdus that still need data. |
| 146 | */ |
| 147 | rd_desc.arg.data = conn; |
| 148 | rd_desc.count = 1; |
| 149 | tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv); |
| 150 | |
| 151 | iscsi_sw_sk_state_check(sk); |
| 152 | |
| 153 | /* If we had to (atomically) map a highmem page, |
| 154 | * unmap it now. */ |
| 155 | iscsi_tcp_segment_unmap(&tcp_conn->in.segment); |
| 156 | read_unlock(&sk->sk_callback_lock); |
| 157 | } |
| 158 | |
| 159 | static void iscsi_sw_tcp_state_change(struct sock *sk) |
| 160 | { |
| 161 | struct iscsi_tcp_conn *tcp_conn; |
| 162 | struct iscsi_sw_tcp_conn *tcp_sw_conn; |
| 163 | struct iscsi_conn *conn; |
| 164 | struct iscsi_session *session; |
| 165 | void (*old_state_change)(struct sock *); |
| 166 | |
| 167 | read_lock(&sk->sk_callback_lock); |
| 168 | conn = sk->sk_user_data; |
| 169 | if (!conn) { |
| 170 | read_unlock(&sk->sk_callback_lock); |
| 171 | return; |
| 172 | } |
| 173 | session = conn->session; |
| 174 | |
| 175 | iscsi_sw_sk_state_check(sk); |
| 176 | |
| 177 | tcp_conn = conn->dd_data; |
| 178 | tcp_sw_conn = tcp_conn->dd_data; |
| 179 | old_state_change = tcp_sw_conn->old_state_change; |
| 180 | |
| 181 | read_unlock(&sk->sk_callback_lock); |
| 182 | |
| 183 | old_state_change(sk); |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * iscsi_write_space - Called when more output buffer space is available |
| 188 | * @sk: socket space is available for |
| 189 | **/ |
| 190 | static void iscsi_sw_tcp_write_space(struct sock *sk) |
| 191 | { |
| 192 | struct iscsi_conn *conn; |
| 193 | struct iscsi_tcp_conn *tcp_conn; |
| 194 | struct iscsi_sw_tcp_conn *tcp_sw_conn; |
| 195 | void (*old_write_space)(struct sock *); |
| 196 | |
| 197 | read_lock_bh(&sk->sk_callback_lock); |
| 198 | conn = sk->sk_user_data; |
| 199 | if (!conn) { |
| 200 | read_unlock_bh(&sk->sk_callback_lock); |
| 201 | return; |
| 202 | } |
| 203 | |
| 204 | tcp_conn = conn->dd_data; |
| 205 | tcp_sw_conn = tcp_conn->dd_data; |
| 206 | old_write_space = tcp_sw_conn->old_write_space; |
| 207 | read_unlock_bh(&sk->sk_callback_lock); |
| 208 | |
| 209 | old_write_space(sk); |
| 210 | |
| 211 | ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n"); |
| 212 | iscsi_conn_queue_work(conn); |
| 213 | } |
| 214 | |
| 215 | static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn) |
| 216 | { |
| 217 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 218 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 219 | struct sock *sk = tcp_sw_conn->sock->sk; |
| 220 | |
| 221 | /* assign new callbacks */ |
| 222 | write_lock_bh(&sk->sk_callback_lock); |
| 223 | sk->sk_user_data = conn; |
| 224 | tcp_sw_conn->old_data_ready = sk->sk_data_ready; |
| 225 | tcp_sw_conn->old_state_change = sk->sk_state_change; |
| 226 | tcp_sw_conn->old_write_space = sk->sk_write_space; |
| 227 | sk->sk_data_ready = iscsi_sw_tcp_data_ready; |
| 228 | sk->sk_state_change = iscsi_sw_tcp_state_change; |
| 229 | sk->sk_write_space = iscsi_sw_tcp_write_space; |
| 230 | write_unlock_bh(&sk->sk_callback_lock); |
| 231 | } |
| 232 | |
| 233 | static void |
| 234 | iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn *conn) |
| 235 | { |
| 236 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 237 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 238 | struct sock *sk = tcp_sw_conn->sock->sk; |
| 239 | |
| 240 | /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */ |
| 241 | write_lock_bh(&sk->sk_callback_lock); |
| 242 | sk->sk_user_data = NULL; |
| 243 | sk->sk_data_ready = tcp_sw_conn->old_data_ready; |
| 244 | sk->sk_state_change = tcp_sw_conn->old_state_change; |
| 245 | sk->sk_write_space = tcp_sw_conn->old_write_space; |
| 246 | sk->sk_no_check = 0; |
| 247 | write_unlock_bh(&sk->sk_callback_lock); |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * iscsi_sw_tcp_xmit_segment - transmit segment |
| 252 | * @tcp_conn: the iSCSI TCP connection |
| 253 | * @segment: the buffer to transmnit |
| 254 | * |
| 255 | * This function transmits as much of the buffer as |
| 256 | * the network layer will accept, and returns the number of |
| 257 | * bytes transmitted. |
| 258 | * |
| 259 | * If CRC hashing is enabled, the function will compute the |
| 260 | * hash as it goes. When the entire segment has been transmitted, |
| 261 | * it will retrieve the hash value and send it as well. |
| 262 | */ |
| 263 | static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn, |
| 264 | struct iscsi_segment *segment) |
| 265 | { |
| 266 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 267 | struct socket *sk = tcp_sw_conn->sock; |
| 268 | unsigned int copied = 0; |
| 269 | int r = 0; |
| 270 | |
| 271 | while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) { |
| 272 | struct scatterlist *sg; |
| 273 | unsigned int offset, copy; |
| 274 | int flags = 0; |
| 275 | |
| 276 | r = 0; |
| 277 | offset = segment->copied; |
| 278 | copy = segment->size - offset; |
| 279 | |
| 280 | if (segment->total_copied + segment->size < segment->total_size) |
| 281 | flags |= MSG_MORE; |
| 282 | |
| 283 | /* Use sendpage if we can; else fall back to sendmsg */ |
| 284 | if (!segment->data) { |
| 285 | sg = segment->sg; |
| 286 | offset += segment->sg_offset + sg->offset; |
| 287 | r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset, |
| 288 | copy, flags); |
| 289 | } else { |
| 290 | struct msghdr msg = { .msg_flags = flags }; |
| 291 | struct kvec iov = { |
| 292 | .iov_base = segment->data + offset, |
| 293 | .iov_len = copy |
| 294 | }; |
| 295 | |
| 296 | r = kernel_sendmsg(sk, &msg, &iov, 1, copy); |
| 297 | } |
| 298 | |
| 299 | if (r < 0) { |
| 300 | iscsi_tcp_segment_unmap(segment); |
| 301 | return r; |
| 302 | } |
| 303 | copied += r; |
| 304 | } |
| 305 | return copied; |
| 306 | } |
| 307 | |
| 308 | /** |
| 309 | * iscsi_sw_tcp_xmit - TCP transmit |
| 310 | **/ |
| 311 | static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn) |
| 312 | { |
| 313 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 314 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 315 | struct iscsi_segment *segment = &tcp_sw_conn->out.segment; |
| 316 | unsigned int consumed = 0; |
| 317 | int rc = 0; |
| 318 | |
| 319 | while (1) { |
| 320 | rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment); |
| 321 | /* |
| 322 | * We may not have been able to send data because the conn |
| 323 | * is getting stopped. libiscsi will know so propagate err |
| 324 | * for it to do the right thing. |
| 325 | */ |
| 326 | if (rc == -EAGAIN) |
| 327 | return rc; |
| 328 | else if (rc < 0) { |
| 329 | rc = ISCSI_ERR_XMIT_FAILED; |
| 330 | goto error; |
| 331 | } else if (rc == 0) |
| 332 | break; |
| 333 | |
| 334 | consumed += rc; |
| 335 | |
| 336 | if (segment->total_copied >= segment->total_size) { |
| 337 | if (segment->done != NULL) { |
| 338 | rc = segment->done(tcp_conn, segment); |
| 339 | if (rc != 0) |
| 340 | goto error; |
| 341 | } |
| 342 | } |
| 343 | } |
| 344 | |
| 345 | ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed); |
| 346 | |
| 347 | conn->txdata_octets += consumed; |
| 348 | return consumed; |
| 349 | |
| 350 | error: |
| 351 | /* Transmit error. We could initiate error recovery |
| 352 | * here. */ |
| 353 | ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc); |
| 354 | iscsi_conn_failure(conn, rc); |
| 355 | return -EIO; |
| 356 | } |
| 357 | |
| 358 | /** |
| 359 | * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit |
| 360 | */ |
| 361 | static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn) |
| 362 | { |
| 363 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 364 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 365 | struct iscsi_segment *segment = &tcp_sw_conn->out.segment; |
| 366 | |
| 367 | return segment->total_copied - segment->total_size; |
| 368 | } |
| 369 | |
| 370 | static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task) |
| 371 | { |
| 372 | struct iscsi_conn *conn = task->conn; |
| 373 | int rc; |
| 374 | |
| 375 | while (iscsi_sw_tcp_xmit_qlen(conn)) { |
| 376 | rc = iscsi_sw_tcp_xmit(conn); |
| 377 | if (rc == 0) |
| 378 | return -EAGAIN; |
| 379 | if (rc < 0) |
| 380 | return rc; |
| 381 | } |
| 382 | |
| 383 | return 0; |
| 384 | } |
| 385 | |
| 386 | /* |
| 387 | * This is called when we're done sending the header. |
| 388 | * Simply copy the data_segment to the send segment, and return. |
| 389 | */ |
| 390 | static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn, |
| 391 | struct iscsi_segment *segment) |
| 392 | { |
| 393 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 394 | |
| 395 | tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment; |
| 396 | ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn, |
| 397 | "Header done. Next segment size %u total_size %u\n", |
| 398 | tcp_sw_conn->out.segment.size, |
| 399 | tcp_sw_conn->out.segment.total_size); |
| 400 | return 0; |
| 401 | } |
| 402 | |
| 403 | static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, |
| 404 | size_t hdrlen) |
| 405 | { |
| 406 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 407 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 408 | |
| 409 | ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ? |
| 410 | "digest enabled" : "digest disabled"); |
| 411 | |
| 412 | /* Clear the data segment - needs to be filled in by the |
| 413 | * caller using iscsi_tcp_send_data_prep() */ |
| 414 | memset(&tcp_sw_conn->out.data_segment, 0, |
| 415 | sizeof(struct iscsi_segment)); |
| 416 | |
| 417 | /* If header digest is enabled, compute the CRC and |
| 418 | * place the digest into the same buffer. We make |
| 419 | * sure that both iscsi_tcp_task and mtask have |
| 420 | * sufficient room. |
| 421 | */ |
| 422 | if (conn->hdrdgst_en) { |
| 423 | iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen, |
| 424 | hdr + hdrlen); |
| 425 | hdrlen += ISCSI_DIGEST_SIZE; |
| 426 | } |
| 427 | |
| 428 | /* Remember header pointer for later, when we need |
| 429 | * to decide whether there's a payload to go along |
| 430 | * with the header. */ |
| 431 | tcp_sw_conn->out.hdr = hdr; |
| 432 | |
| 433 | iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen, |
| 434 | iscsi_sw_tcp_send_hdr_done, NULL); |
| 435 | } |
| 436 | |
| 437 | /* |
| 438 | * Prepare the send buffer for the payload data. |
| 439 | * Padding and checksumming will all be taken care |
| 440 | * of by the iscsi_segment routines. |
| 441 | */ |
| 442 | static int |
| 443 | iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg, |
| 444 | unsigned int count, unsigned int offset, |
| 445 | unsigned int len) |
| 446 | { |
| 447 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 448 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 449 | struct hash_desc *tx_hash = NULL; |
| 450 | unsigned int hdr_spec_len; |
| 451 | |
| 452 | ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len, |
| 453 | conn->datadgst_en ? |
| 454 | "digest enabled" : "digest disabled"); |
| 455 | |
| 456 | /* Make sure the datalen matches what the caller |
| 457 | said he would send. */ |
| 458 | hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); |
| 459 | WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); |
| 460 | |
| 461 | if (conn->datadgst_en) |
| 462 | tx_hash = &tcp_sw_conn->tx_hash; |
| 463 | |
| 464 | return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment, |
| 465 | sg, count, offset, len, |
| 466 | NULL, tx_hash); |
| 467 | } |
| 468 | |
| 469 | static void |
| 470 | iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data, |
| 471 | size_t len) |
| 472 | { |
| 473 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 474 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 475 | struct hash_desc *tx_hash = NULL; |
| 476 | unsigned int hdr_spec_len; |
| 477 | |
| 478 | ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ? |
| 479 | "digest enabled" : "digest disabled"); |
| 480 | |
| 481 | /* Make sure the datalen matches what the caller |
| 482 | said he would send. */ |
| 483 | hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength); |
| 484 | WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len)); |
| 485 | |
| 486 | if (conn->datadgst_en) |
| 487 | tx_hash = &tcp_sw_conn->tx_hash; |
| 488 | |
| 489 | iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment, |
| 490 | data, len, NULL, tx_hash); |
| 491 | } |
| 492 | |
| 493 | static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task, |
| 494 | unsigned int offset, unsigned int count) |
| 495 | { |
| 496 | struct iscsi_conn *conn = task->conn; |
| 497 | int err = 0; |
| 498 | |
| 499 | iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len); |
| 500 | |
| 501 | if (!count) |
| 502 | return 0; |
| 503 | |
| 504 | if (!task->sc) |
| 505 | iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count); |
| 506 | else { |
| 507 | struct scsi_data_buffer *sdb = scsi_out(task->sc); |
| 508 | |
| 509 | err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl, |
| 510 | sdb->table.nents, offset, |
| 511 | count); |
| 512 | } |
| 513 | |
| 514 | if (err) { |
| 515 | /* got invalid offset/len */ |
| 516 | return -EIO; |
| 517 | } |
| 518 | return 0; |
| 519 | } |
| 520 | |
| 521 | static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode) |
| 522 | { |
| 523 | struct iscsi_tcp_task *tcp_task = task->dd_data; |
| 524 | |
| 525 | task->hdr = task->dd_data + sizeof(*tcp_task); |
| 526 | task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE; |
| 527 | return 0; |
| 528 | } |
| 529 | |
| 530 | static struct iscsi_cls_conn * |
| 531 | iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session, |
| 532 | uint32_t conn_idx) |
| 533 | { |
| 534 | struct iscsi_conn *conn; |
| 535 | struct iscsi_cls_conn *cls_conn; |
| 536 | struct iscsi_tcp_conn *tcp_conn; |
| 537 | struct iscsi_sw_tcp_conn *tcp_sw_conn; |
| 538 | |
| 539 | cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn), |
| 540 | conn_idx); |
| 541 | if (!cls_conn) |
| 542 | return NULL; |
| 543 | conn = cls_conn->dd_data; |
| 544 | tcp_conn = conn->dd_data; |
| 545 | tcp_sw_conn = tcp_conn->dd_data; |
| 546 | |
| 547 | tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0, |
| 548 | CRYPTO_ALG_ASYNC); |
| 549 | tcp_sw_conn->tx_hash.flags = 0; |
| 550 | if (IS_ERR(tcp_sw_conn->tx_hash.tfm)) |
| 551 | goto free_conn; |
| 552 | |
| 553 | tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0, |
| 554 | CRYPTO_ALG_ASYNC); |
| 555 | tcp_sw_conn->rx_hash.flags = 0; |
| 556 | if (IS_ERR(tcp_sw_conn->rx_hash.tfm)) |
| 557 | goto free_tx_tfm; |
| 558 | tcp_conn->rx_hash = &tcp_sw_conn->rx_hash; |
| 559 | |
| 560 | return cls_conn; |
| 561 | |
| 562 | free_tx_tfm: |
| 563 | crypto_free_hash(tcp_sw_conn->tx_hash.tfm); |
| 564 | free_conn: |
| 565 | iscsi_conn_printk(KERN_ERR, conn, |
| 566 | "Could not create connection due to crc32c " |
| 567 | "loading error. Make sure the crc32c " |
| 568 | "module is built as a module or into the " |
| 569 | "kernel\n"); |
| 570 | iscsi_tcp_conn_teardown(cls_conn); |
| 571 | return NULL; |
| 572 | } |
| 573 | |
| 574 | static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn) |
| 575 | { |
| 576 | struct iscsi_session *session = conn->session; |
| 577 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 578 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 579 | struct socket *sock = tcp_sw_conn->sock; |
| 580 | |
| 581 | if (!sock) |
| 582 | return; |
| 583 | |
| 584 | sock_hold(sock->sk); |
| 585 | iscsi_sw_tcp_conn_restore_callbacks(conn); |
| 586 | sock_put(sock->sk); |
| 587 | |
| 588 | spin_lock_bh(&session->lock); |
| 589 | tcp_sw_conn->sock = NULL; |
| 590 | spin_unlock_bh(&session->lock); |
| 591 | sockfd_put(sock); |
| 592 | } |
| 593 | |
| 594 | static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn) |
| 595 | { |
| 596 | struct iscsi_conn *conn = cls_conn->dd_data; |
| 597 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 598 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 599 | |
| 600 | iscsi_sw_tcp_release_conn(conn); |
| 601 | |
| 602 | if (tcp_sw_conn->tx_hash.tfm) |
| 603 | crypto_free_hash(tcp_sw_conn->tx_hash.tfm); |
| 604 | if (tcp_sw_conn->rx_hash.tfm) |
| 605 | crypto_free_hash(tcp_sw_conn->rx_hash.tfm); |
| 606 | |
| 607 | iscsi_tcp_conn_teardown(cls_conn); |
| 608 | } |
| 609 | |
| 610 | static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) |
| 611 | { |
| 612 | struct iscsi_conn *conn = cls_conn->dd_data; |
| 613 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 614 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 615 | struct socket *sock = tcp_sw_conn->sock; |
| 616 | |
| 617 | /* userspace may have goofed up and not bound us */ |
| 618 | if (!sock) |
| 619 | return; |
| 620 | |
| 621 | sock->sk->sk_err = EIO; |
| 622 | wake_up_interruptible(sk_sleep(sock->sk)); |
| 623 | |
| 624 | /* stop xmit side */ |
| 625 | iscsi_suspend_tx(conn); |
| 626 | |
| 627 | /* stop recv side and release socket */ |
| 628 | iscsi_sw_tcp_release_conn(conn); |
| 629 | |
| 630 | iscsi_conn_stop(cls_conn, flag); |
| 631 | } |
| 632 | |
| 633 | static int |
| 634 | iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session, |
| 635 | struct iscsi_cls_conn *cls_conn, uint64_t transport_eph, |
| 636 | int is_leading) |
| 637 | { |
| 638 | struct iscsi_session *session = cls_session->dd_data; |
| 639 | struct iscsi_conn *conn = cls_conn->dd_data; |
| 640 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 641 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 642 | struct sock *sk; |
| 643 | struct socket *sock; |
| 644 | int err; |
| 645 | |
| 646 | /* lookup for existing socket */ |
| 647 | sock = sockfd_lookup((int)transport_eph, &err); |
| 648 | if (!sock) { |
| 649 | iscsi_conn_printk(KERN_ERR, conn, |
| 650 | "sockfd_lookup failed %d\n", err); |
| 651 | return -EEXIST; |
| 652 | } |
| 653 | |
| 654 | err = iscsi_conn_bind(cls_session, cls_conn, is_leading); |
| 655 | if (err) |
| 656 | goto free_socket; |
| 657 | |
| 658 | spin_lock_bh(&session->lock); |
| 659 | /* bind iSCSI connection and socket */ |
| 660 | tcp_sw_conn->sock = sock; |
| 661 | spin_unlock_bh(&session->lock); |
| 662 | |
| 663 | /* setup Socket parameters */ |
| 664 | sk = sock->sk; |
| 665 | sk->sk_reuse = SK_CAN_REUSE; |
| 666 | sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */ |
| 667 | sk->sk_allocation = GFP_ATOMIC; |
| 668 | |
| 669 | iscsi_sw_tcp_conn_set_callbacks(conn); |
| 670 | tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage; |
| 671 | /* |
| 672 | * set receive state machine into initial state |
| 673 | */ |
| 674 | iscsi_tcp_hdr_recv_prep(tcp_conn); |
| 675 | return 0; |
| 676 | |
| 677 | free_socket: |
| 678 | sockfd_put(sock); |
| 679 | return err; |
| 680 | } |
| 681 | |
| 682 | static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn, |
| 683 | enum iscsi_param param, char *buf, |
| 684 | int buflen) |
| 685 | { |
| 686 | struct iscsi_conn *conn = cls_conn->dd_data; |
| 687 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 688 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 689 | |
| 690 | switch(param) { |
| 691 | case ISCSI_PARAM_HDRDGST_EN: |
| 692 | iscsi_set_param(cls_conn, param, buf, buflen); |
| 693 | break; |
| 694 | case ISCSI_PARAM_DATADGST_EN: |
| 695 | iscsi_set_param(cls_conn, param, buf, buflen); |
| 696 | tcp_sw_conn->sendpage = conn->datadgst_en ? |
| 697 | sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; |
| 698 | break; |
| 699 | case ISCSI_PARAM_MAX_R2T: |
| 700 | return iscsi_tcp_set_max_r2t(conn, buf); |
| 701 | default: |
| 702 | return iscsi_set_param(cls_conn, param, buf, buflen); |
| 703 | } |
| 704 | |
| 705 | return 0; |
| 706 | } |
| 707 | |
| 708 | static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn, |
| 709 | enum iscsi_param param, char *buf) |
| 710 | { |
| 711 | struct iscsi_conn *conn = cls_conn->dd_data; |
| 712 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 713 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 714 | struct sockaddr_in6 addr; |
| 715 | int rc, len; |
| 716 | |
| 717 | switch(param) { |
| 718 | case ISCSI_PARAM_CONN_PORT: |
| 719 | case ISCSI_PARAM_CONN_ADDRESS: |
| 720 | spin_lock_bh(&conn->session->lock); |
| 721 | if (!tcp_sw_conn || !tcp_sw_conn->sock) { |
| 722 | spin_unlock_bh(&conn->session->lock); |
| 723 | return -ENOTCONN; |
| 724 | } |
| 725 | rc = kernel_getpeername(tcp_sw_conn->sock, |
| 726 | (struct sockaddr *)&addr, &len); |
| 727 | spin_unlock_bh(&conn->session->lock); |
| 728 | if (rc) |
| 729 | return rc; |
| 730 | |
| 731 | return iscsi_conn_get_addr_param((struct sockaddr_storage *) |
| 732 | &addr, param, buf); |
| 733 | default: |
| 734 | return iscsi_conn_get_param(cls_conn, param, buf); |
| 735 | } |
| 736 | |
| 737 | return 0; |
| 738 | } |
| 739 | |
| 740 | static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost, |
| 741 | enum iscsi_host_param param, char *buf) |
| 742 | { |
| 743 | struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost); |
| 744 | struct iscsi_session *session = tcp_sw_host->session; |
| 745 | struct iscsi_conn *conn; |
| 746 | struct iscsi_tcp_conn *tcp_conn; |
| 747 | struct iscsi_sw_tcp_conn *tcp_sw_conn; |
| 748 | struct sockaddr_in6 addr; |
| 749 | int rc, len; |
| 750 | |
| 751 | switch (param) { |
| 752 | case ISCSI_HOST_PARAM_IPADDRESS: |
| 753 | spin_lock_bh(&session->lock); |
| 754 | conn = session->leadconn; |
| 755 | if (!conn) { |
| 756 | spin_unlock_bh(&session->lock); |
| 757 | return -ENOTCONN; |
| 758 | } |
| 759 | tcp_conn = conn->dd_data; |
| 760 | |
| 761 | tcp_sw_conn = tcp_conn->dd_data; |
| 762 | if (!tcp_sw_conn->sock) { |
| 763 | spin_unlock_bh(&session->lock); |
| 764 | return -ENOTCONN; |
| 765 | } |
| 766 | |
| 767 | rc = kernel_getsockname(tcp_sw_conn->sock, |
| 768 | (struct sockaddr *)&addr, &len); |
| 769 | spin_unlock_bh(&session->lock); |
| 770 | if (rc) |
| 771 | return rc; |
| 772 | |
| 773 | return iscsi_conn_get_addr_param((struct sockaddr_storage *) |
| 774 | &addr, param, buf); |
| 775 | default: |
| 776 | return iscsi_host_get_param(shost, param, buf); |
| 777 | } |
| 778 | |
| 779 | return 0; |
| 780 | } |
| 781 | |
| 782 | static void |
| 783 | iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, |
| 784 | struct iscsi_stats *stats) |
| 785 | { |
| 786 | struct iscsi_conn *conn = cls_conn->dd_data; |
| 787 | struct iscsi_tcp_conn *tcp_conn = conn->dd_data; |
| 788 | struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; |
| 789 | |
| 790 | stats->custom_length = 3; |
| 791 | strcpy(stats->custom[0].desc, "tx_sendpage_failures"); |
| 792 | stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt; |
| 793 | strcpy(stats->custom[1].desc, "rx_discontiguous_hdr"); |
| 794 | stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt; |
| 795 | strcpy(stats->custom[2].desc, "eh_abort_cnt"); |
| 796 | stats->custom[2].value = conn->eh_abort_cnt; |
| 797 | |
| 798 | iscsi_tcp_conn_get_stats(cls_conn, stats); |
| 799 | } |
| 800 | |
| 801 | static struct iscsi_cls_session * |
| 802 | iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max, |
| 803 | uint16_t qdepth, uint32_t initial_cmdsn) |
| 804 | { |
| 805 | struct iscsi_cls_session *cls_session; |
| 806 | struct iscsi_session *session; |
| 807 | struct iscsi_sw_tcp_host *tcp_sw_host; |
| 808 | struct Scsi_Host *shost; |
| 809 | |
| 810 | if (ep) { |
| 811 | printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep); |
| 812 | return NULL; |
| 813 | } |
| 814 | |
| 815 | shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, |
| 816 | sizeof(struct iscsi_sw_tcp_host), 1); |
| 817 | if (!shost) |
| 818 | return NULL; |
| 819 | shost->transportt = iscsi_sw_tcp_scsi_transport; |
| 820 | shost->cmd_per_lun = qdepth; |
| 821 | shost->max_lun = iscsi_max_lun; |
| 822 | shost->max_id = 0; |
| 823 | shost->max_channel = 0; |
| 824 | shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE; |
| 825 | |
| 826 | if (iscsi_host_add(shost, NULL)) |
| 827 | goto free_host; |
| 828 | |
| 829 | cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost, |
| 830 | cmds_max, 0, |
| 831 | sizeof(struct iscsi_tcp_task) + |
| 832 | sizeof(struct iscsi_sw_tcp_hdrbuf), |
| 833 | initial_cmdsn, 0); |
| 834 | if (!cls_session) |
| 835 | goto remove_host; |
| 836 | session = cls_session->dd_data; |
| 837 | tcp_sw_host = iscsi_host_priv(shost); |
| 838 | tcp_sw_host->session = session; |
| 839 | |
| 840 | shost->can_queue = session->scsi_cmds_max; |
| 841 | if (iscsi_tcp_r2tpool_alloc(session)) |
| 842 | goto remove_session; |
| 843 | return cls_session; |
| 844 | |
| 845 | remove_session: |
| 846 | iscsi_session_teardown(cls_session); |
| 847 | remove_host: |
| 848 | iscsi_host_remove(shost); |
| 849 | free_host: |
| 850 | iscsi_host_free(shost); |
| 851 | return NULL; |
| 852 | } |
| 853 | |
| 854 | static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session) |
| 855 | { |
| 856 | struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); |
| 857 | |
| 858 | iscsi_tcp_r2tpool_free(cls_session->dd_data); |
| 859 | iscsi_session_teardown(cls_session); |
| 860 | |
| 861 | iscsi_host_remove(shost); |
| 862 | iscsi_host_free(shost); |
| 863 | } |
| 864 | |
| 865 | static umode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param) |
| 866 | { |
| 867 | switch (param_type) { |
| 868 | case ISCSI_HOST_PARAM: |
| 869 | switch (param) { |
| 870 | case ISCSI_HOST_PARAM_NETDEV_NAME: |
| 871 | case ISCSI_HOST_PARAM_HWADDRESS: |
| 872 | case ISCSI_HOST_PARAM_IPADDRESS: |
| 873 | case ISCSI_HOST_PARAM_INITIATOR_NAME: |
| 874 | return S_IRUGO; |
| 875 | default: |
| 876 | return 0; |
| 877 | } |
| 878 | case ISCSI_PARAM: |
| 879 | switch (param) { |
| 880 | case ISCSI_PARAM_MAX_RECV_DLENGTH: |
| 881 | case ISCSI_PARAM_MAX_XMIT_DLENGTH: |
| 882 | case ISCSI_PARAM_HDRDGST_EN: |
| 883 | case ISCSI_PARAM_DATADGST_EN: |
| 884 | case ISCSI_PARAM_CONN_ADDRESS: |
| 885 | case ISCSI_PARAM_CONN_PORT: |
| 886 | case ISCSI_PARAM_EXP_STATSN: |
| 887 | case ISCSI_PARAM_PERSISTENT_ADDRESS: |
| 888 | case ISCSI_PARAM_PERSISTENT_PORT: |
| 889 | case ISCSI_PARAM_PING_TMO: |
| 890 | case ISCSI_PARAM_RECV_TMO: |
| 891 | case ISCSI_PARAM_INITIAL_R2T_EN: |
| 892 | case ISCSI_PARAM_MAX_R2T: |
| 893 | case ISCSI_PARAM_IMM_DATA_EN: |
| 894 | case ISCSI_PARAM_FIRST_BURST: |
| 895 | case ISCSI_PARAM_MAX_BURST: |
| 896 | case ISCSI_PARAM_PDU_INORDER_EN: |
| 897 | case ISCSI_PARAM_DATASEQ_INORDER_EN: |
| 898 | case ISCSI_PARAM_ERL: |
| 899 | case ISCSI_PARAM_TARGET_NAME: |
| 900 | case ISCSI_PARAM_TPGT: |
| 901 | case ISCSI_PARAM_USERNAME: |
| 902 | case ISCSI_PARAM_PASSWORD: |
| 903 | case ISCSI_PARAM_USERNAME_IN: |
| 904 | case ISCSI_PARAM_PASSWORD_IN: |
| 905 | case ISCSI_PARAM_FAST_ABORT: |
| 906 | case ISCSI_PARAM_ABORT_TMO: |
| 907 | case ISCSI_PARAM_LU_RESET_TMO: |
| 908 | case ISCSI_PARAM_TGT_RESET_TMO: |
| 909 | case ISCSI_PARAM_IFACE_NAME: |
| 910 | case ISCSI_PARAM_INITIATOR_NAME: |
| 911 | return S_IRUGO; |
| 912 | default: |
| 913 | return 0; |
| 914 | } |
| 915 | } |
| 916 | |
| 917 | return 0; |
| 918 | } |
| 919 | |
| 920 | static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev) |
| 921 | { |
| 922 | set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags); |
| 923 | return 0; |
| 924 | } |
| 925 | |
| 926 | static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev) |
| 927 | { |
| 928 | blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY); |
| 929 | blk_queue_dma_alignment(sdev->request_queue, 0); |
| 930 | return 0; |
| 931 | } |
| 932 | |
| 933 | static struct scsi_host_template iscsi_sw_tcp_sht = { |
| 934 | .module = THIS_MODULE, |
| 935 | .name = "iSCSI Initiator over TCP/IP", |
| 936 | .queuecommand = iscsi_queuecommand, |
| 937 | .change_queue_depth = iscsi_change_queue_depth, |
| 938 | .can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1, |
| 939 | .sg_tablesize = 4096, |
| 940 | .max_sectors = 0xFFFF, |
| 941 | .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN, |
| 942 | .eh_abort_handler = iscsi_eh_abort, |
| 943 | .eh_device_reset_handler= iscsi_eh_device_reset, |
| 944 | .eh_target_reset_handler = iscsi_eh_recover_target, |
| 945 | .use_clustering = DISABLE_CLUSTERING, |
| 946 | .slave_alloc = iscsi_sw_tcp_slave_alloc, |
| 947 | .slave_configure = iscsi_sw_tcp_slave_configure, |
| 948 | .target_alloc = iscsi_target_alloc, |
| 949 | .proc_name = "iscsi_tcp", |
| 950 | .this_id = -1, |
| 951 | }; |
| 952 | |
| 953 | static struct iscsi_transport iscsi_sw_tcp_transport = { |
| 954 | .owner = THIS_MODULE, |
| 955 | .name = "tcp", |
| 956 | .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST |
| 957 | | CAP_DATADGST, |
| 958 | /* session management */ |
| 959 | .create_session = iscsi_sw_tcp_session_create, |
| 960 | .destroy_session = iscsi_sw_tcp_session_destroy, |
| 961 | /* connection management */ |
| 962 | .create_conn = iscsi_sw_tcp_conn_create, |
| 963 | .bind_conn = iscsi_sw_tcp_conn_bind, |
| 964 | .destroy_conn = iscsi_sw_tcp_conn_destroy, |
| 965 | .attr_is_visible = iscsi_sw_tcp_attr_is_visible, |
| 966 | .set_param = iscsi_sw_tcp_conn_set_param, |
| 967 | .get_conn_param = iscsi_sw_tcp_conn_get_param, |
| 968 | .get_session_param = iscsi_session_get_param, |
| 969 | .start_conn = iscsi_conn_start, |
| 970 | .stop_conn = iscsi_sw_tcp_conn_stop, |
| 971 | /* iscsi host params */ |
| 972 | .get_host_param = iscsi_sw_tcp_host_get_param, |
| 973 | .set_host_param = iscsi_host_set_param, |
| 974 | /* IO */ |
| 975 | .send_pdu = iscsi_conn_send_pdu, |
| 976 | .get_stats = iscsi_sw_tcp_conn_get_stats, |
| 977 | /* iscsi task/cmd helpers */ |
| 978 | .init_task = iscsi_tcp_task_init, |
| 979 | .xmit_task = iscsi_tcp_task_xmit, |
| 980 | .cleanup_task = iscsi_tcp_cleanup_task, |
| 981 | /* low level pdu helpers */ |
| 982 | .xmit_pdu = iscsi_sw_tcp_pdu_xmit, |
| 983 | .init_pdu = iscsi_sw_tcp_pdu_init, |
| 984 | .alloc_pdu = iscsi_sw_tcp_pdu_alloc, |
| 985 | /* recovery */ |
| 986 | .session_recovery_timedout = iscsi_session_recovery_timedout, |
| 987 | }; |
| 988 | |
| 989 | static int __init iscsi_sw_tcp_init(void) |
| 990 | { |
| 991 | if (iscsi_max_lun < 1) { |
| 992 | printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n", |
| 993 | iscsi_max_lun); |
| 994 | return -EINVAL; |
| 995 | } |
| 996 | |
| 997 | iscsi_sw_tcp_scsi_transport = iscsi_register_transport( |
| 998 | &iscsi_sw_tcp_transport); |
| 999 | if (!iscsi_sw_tcp_scsi_transport) |
| 1000 | return -ENODEV; |
| 1001 | |
| 1002 | return 0; |
| 1003 | } |
| 1004 | |
| 1005 | static void __exit iscsi_sw_tcp_exit(void) |
| 1006 | { |
| 1007 | iscsi_unregister_transport(&iscsi_sw_tcp_transport); |
| 1008 | } |
| 1009 | |
| 1010 | module_init(iscsi_sw_tcp_init); |
| 1011 | module_exit(iscsi_sw_tcp_exit); |