SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/scsi/iscsi_tcp.c

   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         if ((sk->sk_state == TCP_CLOSE_WAIT ||
 113              sk->sk_state == TCP_CLOSE) &&
 114             !atomic_read(&sk->sk_rmem_alloc))
 115                 return -ECONNRESET;
 116
 117         return 0;
 118 }
 119
 120 static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag)
 121 {
 122         struct iscsi_conn *conn = sk->sk_user_data;
 123         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 124         read_descriptor_t rd_desc;
 125
 126         read_lock(&sk->sk_callback_lock);
 127
 128         /*
 129          * Use rd_desc to pass 'conn' to iscsi_tcp_recv.
 130          * We set count to 1 because we want the network layer to
 131          * hand us all the skbs that are available. iscsi_tcp_recv
 132          * handled pdus that cross buffers or pdus that still need data.
 133          */
 134         rd_desc.arg.data = conn;
 135         rd_desc.count = 1;
 136         tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv);
 137
 138         if (iscsi_sw_sk_state_check(sk) < 0) {
 139                 ISCSI_SW_TCP_DBG(conn, "iscsi_tcp_data_ready: "
 140                                  "TCP_CLOSE|TCP_CLOSE_WAIT\n");
 141                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 142         }
 143
 144         read_unlock(&sk->sk_callback_lock);
 145
 146         /* If we had to (atomically) map a highmem page,
 147          * unmap it now. */
 148         iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
 149 }
 150
 151 static void iscsi_sw_tcp_state_change(struct sock *sk)
 152 {
 153         struct iscsi_tcp_conn *tcp_conn;
 154         struct iscsi_sw_tcp_conn *tcp_sw_conn;
 155         struct iscsi_conn *conn;
 156         struct iscsi_session *session;
 157         void (*old_state_change)(struct sock *);
 158
 159         read_lock(&sk->sk_callback_lock);
 160
 161         conn = (struct iscsi_conn*)sk->sk_user_data;
 162         session = conn->session;
 163
 164         if (iscsi_sw_sk_state_check(sk) < 0) {
 165                 ISCSI_SW_TCP_DBG(conn, "iscsi_tcp_state_change: "
 166                                  "TCP_CLOSE|TCP_CLOSE_WAIT\n");
 167                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 168         }
 169
 170         tcp_conn = conn->dd_data;
 171         tcp_sw_conn = tcp_conn->dd_data;
 172         old_state_change = tcp_sw_conn->old_state_change;
 173
 174         read_unlock(&sk->sk_callback_lock);
 175
 176         old_state_change(sk);
 177 }
 178
 179 /**
 180  * iscsi_write_space - Called when more output buffer space is available
 181  * @sk: socket space is available for
 182  **/
 183 static void iscsi_sw_tcp_write_space(struct sock *sk)
 184 {
 185         struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
 186         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 187         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 188
 189         tcp_sw_conn->old_write_space(sk);
 190         ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
 191         iscsi_conn_queue_work(conn);
 192 }
 193
 194 static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
 195 {
 196         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 197         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 198         struct sock *sk = tcp_sw_conn->sock->sk;
 199
 200         /* assign new callbacks */
 201         write_lock_bh(&sk->sk_callback_lock);
 202         sk->sk_user_data = conn;
 203         tcp_sw_conn->old_data_ready = sk->sk_data_ready;
 204         tcp_sw_conn->old_state_change = sk->sk_state_change;
 205         tcp_sw_conn->old_write_space = sk->sk_write_space;
 206         sk->sk_data_ready = iscsi_sw_tcp_data_ready;
 207         sk->sk_state_change = iscsi_sw_tcp_state_change;
 208         sk->sk_write_space = iscsi_sw_tcp_write_space;
 209         write_unlock_bh(&sk->sk_callback_lock);
 210 }
 211
 212 static void
 213 iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn)
 214 {
 215         struct sock *sk = tcp_sw_conn->sock->sk;
 216
 217         /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
 218         write_lock_bh(&sk->sk_callback_lock);
 219         sk->sk_user_data    = NULL;
 220         sk->sk_data_ready   = tcp_sw_conn->old_data_ready;
 221         sk->sk_state_change = tcp_sw_conn->old_state_change;
 222         sk->sk_write_space  = tcp_sw_conn->old_write_space;
 223         sk->sk_no_check  = 0;
 224         write_unlock_bh(&sk->sk_callback_lock);
 225 }
 226
 227 /**
 228  * iscsi_sw_tcp_xmit_segment - transmit segment
 229  * @tcp_conn: the iSCSI TCP connection
 230  * @segment: the buffer to transmnit
 231  *
 232  * This function transmits as much of the buffer as
 233  * the network layer will accept, and returns the number of
 234  * bytes transmitted.
 235  *
 236  * If CRC hashing is enabled, the function will compute the
 237  * hash as it goes. When the entire segment has been transmitted,
 238  * it will retrieve the hash value and send it as well.
 239  */
 240 static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
 241                                      struct iscsi_segment *segment)
 242 {
 243         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 244         struct socket *sk = tcp_sw_conn->sock;
 245         unsigned int copied = 0;
 246         int r = 0;
 247
 248         while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
 249                 struct scatterlist *sg;
 250                 unsigned int offset, copy;
 251                 int flags = 0;
 252
 253                 r = 0;
 254                 offset = segment->copied;
 255                 copy = segment->size - offset;
 256
 257                 if (segment->total_copied + segment->size < segment->total_size)
 258                         flags |= MSG_MORE;
 259
 260                 /* Use sendpage if we can; else fall back to sendmsg */
 261                 if (!segment->data) {
 262                         sg = segment->sg;
 263                         offset += segment->sg_offset + sg->offset;
 264                         r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
 265                                                   copy, flags);
 266                 } else {
 267                         struct msghdr msg = { .msg_flags = flags };
 268                         struct kvec iov = {
 269                                 .iov_base = segment->data + offset,
 270                                 .iov_len = copy
 271                         };
 272
 273                         r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
 274                 }
 275
 276                 if (r < 0) {
 277                         iscsi_tcp_segment_unmap(segment);
 278                         return r;
 279                 }
 280                 copied += r;
 281         }
 282         return copied;
 283 }
 284
 285 /**
 286  * iscsi_sw_tcp_xmit - TCP transmit
 287  **/
 288 static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
 289 {
 290         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 291         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 292         struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
 293         unsigned int consumed = 0;
 294         int rc = 0;
 295
 296         while (1) {
 297                 rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
 298                 /*
 299                  * We may not have been able to send data because the conn
 300                  * is getting stopped. libiscsi will know so propogate err
 301                  * for it to do the right thing.
 302                  */
 303                 if (rc == -EAGAIN)
 304                         return rc;
 305                 else if (rc < 0) {
 306                         rc = ISCSI_ERR_XMIT_FAILED;
 307                         goto error;
 308                 } else if (rc == 0)
 309                         break;
 310
 311                 consumed += rc;
 312
 313                 if (segment->total_copied >= segment->total_size) {
 314                         if (segment->done != NULL) {
 315                                 rc = segment->done(tcp_conn, segment);
 316                                 if (rc != 0)
 317                                         goto error;
 318                         }
 319                 }
 320         }
 321
 322         ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
 323
 324         conn->txdata_octets += consumed;
 325         return consumed;
 326
 327 error:
 328         /* Transmit error. We could initiate error recovery
 329          * here. */
 330         ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc);
 331         iscsi_conn_failure(conn, rc);
 332         return -EIO;
 333 }
 334
 335 /**
 336  * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
 337  */
 338 static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
 339 {
 340         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 341         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 342         struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
 343
 344         return segment->total_copied - segment->total_size;
 345 }
 346
 347 static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
 348 {
 349         struct iscsi_conn *conn = task->conn;
 350         int rc;
 351
 352         while (iscsi_sw_tcp_xmit_qlen(conn)) {
 353                 rc = iscsi_sw_tcp_xmit(conn);
 354                 if (rc == 0)
 355                         return -EAGAIN;
 356                 if (rc < 0)
 357                         return rc;
 358         }
 359
 360         return 0;
 361 }
 362
 363 /*
 364  * This is called when we're done sending the header.
 365  * Simply copy the data_segment to the send segment, and return.
 366  */
 367 static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
 368                                       struct iscsi_segment *segment)
 369 {
 370         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 371
 372         tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
 373         ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
 374                          "Header done. Next segment size %u total_size %u\n",
 375                          tcp_sw_conn->out.segment.size,
 376                          tcp_sw_conn->out.segment.total_size);
 377         return 0;
 378 }
 379
 380 static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
 381                                        size_t hdrlen)
 382 {
 383         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 384         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 385
 386         ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
 387                          "digest enabled" : "digest disabled");
 388
 389         /* Clear the data segment - needs to be filled in by the
 390          * caller using iscsi_tcp_send_data_prep() */
 391         memset(&tcp_sw_conn->out.data_segment, 0,
 392                sizeof(struct iscsi_segment));
 393
 394         /* If header digest is enabled, compute the CRC and
 395          * place the digest into the same buffer. We make
 396          * sure that both iscsi_tcp_task and mtask have
 397          * sufficient room.
 398          */
 399         if (conn->hdrdgst_en) {
 400                 iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen,
 401                                       hdr + hdrlen);
 402                 hdrlen += ISCSI_DIGEST_SIZE;
 403         }
 404
 405         /* Remember header pointer for later, when we need
 406          * to decide whether there's a payload to go along
 407          * with the header. */
 408         tcp_sw_conn->out.hdr = hdr;
 409
 410         iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
 411                                   iscsi_sw_tcp_send_hdr_done, NULL);
 412 }
 413
 414 /*
 415  * Prepare the send buffer for the payload data.
 416  * Padding and checksumming will all be taken care
 417  * of by the iscsi_segment routines.
 418  */
 419 static int
 420 iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
 421                             unsigned int count, unsigned int offset,
 422                             unsigned int len)
 423 {
 424         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 425         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 426         struct hash_desc *tx_hash = NULL;
 427         unsigned int hdr_spec_len;
 428
 429         ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
 430                          conn->datadgst_en ?
 431                          "digest enabled" : "digest disabled");
 432
 433         /* Make sure the datalen matches what the caller
 434            said he would send. */
 435         hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
 436         WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
 437
 438         if (conn->datadgst_en)
 439                 tx_hash = &tcp_sw_conn->tx_hash;
 440
 441         return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
 442                                      sg, count, offset, len,
 443                                      NULL, tx_hash);
 444 }
 445
 446 static void
 447 iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
 448                                    size_t len)
 449 {
 450         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 451         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 452         struct hash_desc *tx_hash = NULL;
 453         unsigned int hdr_spec_len;
 454
 455         ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
 456                          "digest enabled" : "digest disabled");
 457
 458         /* Make sure the datalen matches what the caller
 459            said he would send. */
 460         hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
 461         WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
 462
 463         if (conn->datadgst_en)
 464                 tx_hash = &tcp_sw_conn->tx_hash;
 465
 466         iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
 467                                 data, len, NULL, tx_hash);
 468 }
 469
 470 static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
 471                                  unsigned int offset, unsigned int count)
 472 {
 473         struct iscsi_conn *conn = task->conn;
 474         int err = 0;
 475
 476         iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
 477
 478         if (!count)
 479                 return 0;
 480
 481         if (!task->sc)
 482                 iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
 483         else {
 484                 struct scsi_data_buffer *sdb = scsi_out(task->sc);
 485
 486                 err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
 487                                                   sdb->table.nents, offset,
 488                                                   count);
 489         }
 490
 491         if (err) {
 492                 /* got invalid offset/len */
 493                 return -EIO;
 494         }
 495         return 0;
 496 }
 497
 498 static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
 499 {
 500         struct iscsi_tcp_task *tcp_task = task->dd_data;
 501
 502         task->hdr = task->dd_data + sizeof(*tcp_task);
 503         task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
 504         return 0;
 505 }
 506
 507 static struct iscsi_cls_conn *
 508 iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
 509                          uint32_t conn_idx)
 510 {
 511         struct iscsi_conn *conn;
 512         struct iscsi_cls_conn *cls_conn;
 513         struct iscsi_tcp_conn *tcp_conn;
 514         struct iscsi_sw_tcp_conn *tcp_sw_conn;
 515
 516         cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
 517                                         conn_idx);
 518         if (!cls_conn)
 519                 return NULL;
 520         conn = cls_conn->dd_data;
 521         tcp_conn = conn->dd_data;
 522         tcp_sw_conn = tcp_conn->dd_data;
 523
 524         tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
 525                                                      CRYPTO_ALG_ASYNC);
 526         tcp_sw_conn->tx_hash.flags = 0;
 527         if (IS_ERR(tcp_sw_conn->tx_hash.tfm))
 528                 goto free_conn;
 529
 530         tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
 531                                                      CRYPTO_ALG_ASYNC);
 532         tcp_sw_conn->rx_hash.flags = 0;
 533         if (IS_ERR(tcp_sw_conn->rx_hash.tfm))
 534                 goto free_tx_tfm;
 535         tcp_conn->rx_hash = &tcp_sw_conn->rx_hash;
 536
 537         return cls_conn;
 538
 539 free_tx_tfm:
 540         crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
 541 free_conn:
 542         iscsi_conn_printk(KERN_ERR, conn,
 543                           "Could not create connection due to crc32c "
 544                           "loading error. Make sure the crc32c "
 545                           "module is built as a module or into the "
 546                           "kernel\n");
 547         iscsi_tcp_conn_teardown(cls_conn);
 548         return NULL;
 549 }
 550
 551 static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
 552 {
 553         struct iscsi_session *session = conn->session;
 554         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 555         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 556         struct socket *sock = tcp_sw_conn->sock;
 557
 558         if (!sock)
 559                 return;
 560
 561         sock_hold(sock->sk);
 562         iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn);
 563         sock_put(sock->sk);
 564
 565         spin_lock_bh(&session->lock);
 566         tcp_sw_conn->sock = NULL;
 567         spin_unlock_bh(&session->lock);
 568         sockfd_put(sock);
 569 }
 570
 571 static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
 572 {
 573         struct iscsi_conn *conn = cls_conn->dd_data;
 574         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 575         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 576
 577         iscsi_sw_tcp_release_conn(conn);
 578
 579         if (tcp_sw_conn->tx_hash.tfm)
 580                 crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
 581         if (tcp_sw_conn->rx_hash.tfm)
 582                 crypto_free_hash(tcp_sw_conn->rx_hash.tfm);
 583
 584         iscsi_tcp_conn_teardown(cls_conn);
 585 }
 586
 587 static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 588 {
 589         struct iscsi_conn *conn = cls_conn->dd_data;
 590         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 591         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 592
 593         /* userspace may have goofed up and not bound us */
 594         if (!tcp_sw_conn->sock)
 595                 return;
 596         /*
 597          * Make sure our recv side is stopped.
 598          * Older tools called conn stop before ep_disconnect
 599          * so IO could still be coming in.
 600          */
 601         write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
 602         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 603         write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
 604
 605         iscsi_conn_stop(cls_conn, flag);
 606         iscsi_sw_tcp_release_conn(conn);
 607 }
 608
 609 static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
 610                                  char *buf, int *port,
 611                                  int (*getname)(struct socket *,
 612                                                 struct sockaddr *,
 613                                                 int *addrlen))
 614 {
 615         struct sockaddr_storage *addr;
 616         struct sockaddr_in6 *sin6;
 617         struct sockaddr_in *sin;
 618         int rc = 0, len;
 619
 620         addr = kmalloc(sizeof(*addr), GFP_KERNEL);
 621         if (!addr)
 622                 return -ENOMEM;
 623
 624         if (getname(sock, (struct sockaddr *) addr, &len)) {
 625                 rc = -ENODEV;
 626                 goto free_addr;
 627         }
 628
 629         switch (addr->ss_family) {
 630         case AF_INET:
 631                 sin = (struct sockaddr_in *)addr;
 632                 spin_lock_bh(&conn->session->lock);
 633                 sprintf(buf, "%pI4", &sin->sin_addr.s_addr);
 634                 *port = be16_to_cpu(sin->sin_port);
 635                 spin_unlock_bh(&conn->session->lock);
 636                 break;
 637         case AF_INET6:
 638                 sin6 = (struct sockaddr_in6 *)addr;
 639                 spin_lock_bh(&conn->session->lock);
 640                 sprintf(buf, "%pI6", &sin6->sin6_addr);
 641                 *port = be16_to_cpu(sin6->sin6_port);
 642                 spin_unlock_bh(&conn->session->lock);
 643                 break;
 644         }
 645 free_addr:
 646         kfree(addr);
 647         return rc;
 648 }
 649
 650 static int
 651 iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
 652                        struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
 653                        int is_leading)
 654 {
 655         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 656         struct iscsi_host *ihost = shost_priv(shost);
 657         struct iscsi_conn *conn = cls_conn->dd_data;
 658         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 659         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 660         struct sock *sk;
 661         struct socket *sock;
 662         int err;
 663
 664         /* lookup for existing socket */
 665         sock = sockfd_lookup((int)transport_eph, &err);
 666         if (!sock) {
 667                 iscsi_conn_printk(KERN_ERR, conn,
 668                                   "sockfd_lookup failed %d\n", err);
 669                 return -EEXIST;
 670         }
 671         /*
 672          * copy these values now because if we drop the session
 673          * userspace may still want to query the values since we will
 674          * be using them for the reconnect
 675          */
 676         err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address,
 677                                     &conn->portal_port, kernel_getpeername);
 678         if (err)
 679                 goto free_socket;
 680
 681         err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address,
 682                                     &ihost->local_port, kernel_getsockname);
 683         if (err)
 684                 goto free_socket;
 685
 686         err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
 687         if (err)
 688                 goto free_socket;
 689
 690         /* bind iSCSI connection and socket */
 691         tcp_sw_conn->sock = sock;
 692
 693         /* setup Socket parameters */
 694         sk = sock->sk;
 695         sk->sk_reuse = 1;
 696         sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
 697         sk->sk_allocation = GFP_ATOMIC;
 698
 699         iscsi_sw_tcp_conn_set_callbacks(conn);
 700         tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
 701         /*
 702          * set receive state machine into initial state
 703          */
 704         iscsi_tcp_hdr_recv_prep(tcp_conn);
 705         return 0;
 706
 707 free_socket:
 708         sockfd_put(sock);
 709         return err;
 710 }
 711
 712 static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
 713                                        enum iscsi_param param, char *buf,
 714                                        int buflen)
 715 {
 716         struct iscsi_conn *conn = cls_conn->dd_data;
 717         struct iscsi_session *session = conn->session;
 718         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 719         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 720         int value;
 721
 722         switch(param) {
 723         case ISCSI_PARAM_HDRDGST_EN:
 724                 iscsi_set_param(cls_conn, param, buf, buflen);
 725                 break;
 726         case ISCSI_PARAM_DATADGST_EN:
 727                 iscsi_set_param(cls_conn, param, buf, buflen);
 728                 tcp_sw_conn->sendpage = conn->datadgst_en ?
 729                         sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
 730                 break;
 731         case ISCSI_PARAM_MAX_R2T:
 732                 sscanf(buf, "%d", &value);
 733                 if (value <= 0 || !is_power_of_2(value))
 734                         return -EINVAL;
 735                 if (session->max_r2t == value)
 736                         break;
 737                 iscsi_tcp_r2tpool_free(session);
 738                 iscsi_set_param(cls_conn, param, buf, buflen);
 739                 if (iscsi_tcp_r2tpool_alloc(session))
 740                         return -ENOMEM;
 741                 break;
 742         default:
 743                 return iscsi_set_param(cls_conn, param, buf, buflen);
 744         }
 745
 746         return 0;
 747 }
 748
 749 static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
 750                                        enum iscsi_param param, char *buf)
 751 {
 752         struct iscsi_conn *conn = cls_conn->dd_data;
 753         int len;
 754
 755         switch(param) {
 756         case ISCSI_PARAM_CONN_PORT:
 757                 spin_lock_bh(&conn->session->lock);
 758                 len = sprintf(buf, "%hu\n", conn->portal_port);
 759                 spin_unlock_bh(&conn->session->lock);
 760                 break;
 761         case ISCSI_PARAM_CONN_ADDRESS:
 762                 spin_lock_bh(&conn->session->lock);
 763                 len = sprintf(buf, "%s\n", conn->portal_address);
 764                 spin_unlock_bh(&conn->session->lock);
 765                 break;
 766         default:
 767                 return iscsi_conn_get_param(cls_conn, param, buf);
 768         }
 769
 770         return len;
 771 }
 772
 773 static void
 774 iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
 775                             struct iscsi_stats *stats)
 776 {
 777         struct iscsi_conn *conn = cls_conn->dd_data;
 778         struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 779         struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 780
 781         stats->custom_length = 3;
 782         strcpy(stats->custom[0].desc, "tx_sendpage_failures");
 783         stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
 784         strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
 785         stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
 786         strcpy(stats->custom[2].desc, "eh_abort_cnt");
 787         stats->custom[2].value = conn->eh_abort_cnt;
 788
 789         iscsi_tcp_conn_get_stats(cls_conn, stats);
 790 }
 791
 792 static struct iscsi_cls_session *
 793 iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
 794                             uint16_t qdepth, uint32_t initial_cmdsn)
 795 {
 796         struct iscsi_cls_session *cls_session;
 797         struct iscsi_session *session;
 798         struct Scsi_Host *shost;
 799
 800         if (ep) {
 801                 printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
 802                 return NULL;
 803         }
 804
 805         shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, 1);
 806         if (!shost)
 807                 return NULL;
 808         shost->transportt = iscsi_sw_tcp_scsi_transport;
 809         shost->cmd_per_lun = qdepth;
 810         shost->max_lun = iscsi_max_lun;
 811         shost->max_id = 0;
 812         shost->max_channel = 0;
 813         shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 814
 815         if (iscsi_host_add(shost, NULL))
 816                 goto free_host;
 817
 818         cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
 819                                           cmds_max,
 820                                           sizeof(struct iscsi_tcp_task) +
 821                                           sizeof(struct iscsi_sw_tcp_hdrbuf),
 822                                           initial_cmdsn, 0);
 823         if (!cls_session)
 824                 goto remove_host;
 825         session = cls_session->dd_data;
 826
 827         shost->can_queue = session->scsi_cmds_max;
 828         if (iscsi_tcp_r2tpool_alloc(session))
 829                 goto remove_session;
 830         return cls_session;
 831
 832 remove_session:
 833         iscsi_session_teardown(cls_session);
 834 remove_host:
 835         iscsi_host_remove(shost);
 836 free_host:
 837         iscsi_host_free(shost);
 838         return NULL;
 839 }
 840
 841 static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
 842 {
 843         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 844
 845         iscsi_tcp_r2tpool_free(cls_session->dd_data);
 846         iscsi_session_teardown(cls_session);
 847
 848         iscsi_host_remove(shost);
 849         iscsi_host_free(shost);
 850 }
 851
 852 static int iscsi_sw_tcp_slave_alloc(struct scsi_device *sdev)
 853 {
 854         set_bit(QUEUE_FLAG_BIDI, &sdev->request_queue->queue_flags);
 855         return 0;
 856 }
 857
 858 static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
 859 {
 860         blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
 861         blk_queue_dma_alignment(sdev->request_queue, 0);
 862         return 0;
 863 }
 864
 865 static struct scsi_host_template iscsi_sw_tcp_sht = {
 866         .module                 = THIS_MODULE,
 867         .name                   = "iSCSI Initiator over TCP/IP",
 868         .queuecommand           = iscsi_queuecommand,
 869         .change_queue_depth     = iscsi_change_queue_depth,
 870         .can_queue              = ISCSI_DEF_XMIT_CMDS_MAX - 1,
 871         .sg_tablesize           = 4096,
 872         .max_sectors            = 0xFFFF,
 873         .cmd_per_lun            = ISCSI_DEF_CMD_PER_LUN,
 874         .eh_abort_handler       = iscsi_eh_abort,
 875         .eh_device_reset_handler= iscsi_eh_device_reset,
 876         .eh_target_reset_handler= iscsi_eh_target_reset,
 877         .use_clustering         = DISABLE_CLUSTERING,
 878         .slave_alloc            = iscsi_sw_tcp_slave_alloc,
 879         .slave_configure        = iscsi_sw_tcp_slave_configure,
 880         .target_alloc           = iscsi_target_alloc,
 881         .proc_name              = "iscsi_tcp",
 882         .this_id                = -1,
 883 };
 884
 885 static struct iscsi_transport iscsi_sw_tcp_transport = {
 886         .owner                  = THIS_MODULE,
 887         .name                   = "tcp",
 888         .caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
 889                                   | CAP_DATADGST,
 890         .param_mask             = ISCSI_MAX_RECV_DLENGTH |
 891                                   ISCSI_MAX_XMIT_DLENGTH |
 892                                   ISCSI_HDRDGST_EN |
 893                                   ISCSI_DATADGST_EN |
 894                                   ISCSI_INITIAL_R2T_EN |
 895                                   ISCSI_MAX_R2T |
 896                                   ISCSI_IMM_DATA_EN |
 897                                   ISCSI_FIRST_BURST |
 898                                   ISCSI_MAX_BURST |
 899                                   ISCSI_PDU_INORDER_EN |
 900                                   ISCSI_DATASEQ_INORDER_EN |
 901                                   ISCSI_ERL |
 902                                   ISCSI_CONN_PORT |
 903                                   ISCSI_CONN_ADDRESS |
 904                                   ISCSI_EXP_STATSN |
 905                                   ISCSI_PERSISTENT_PORT |
 906                                   ISCSI_PERSISTENT_ADDRESS |
 907                                   ISCSI_TARGET_NAME | ISCSI_TPGT |
 908                                   ISCSI_USERNAME | ISCSI_PASSWORD |
 909                                   ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
 910                                   ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
 911                                   ISCSI_LU_RESET_TMO |
 912                                   ISCSI_PING_TMO | ISCSI_RECV_TMO |
 913                                   ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME,
 914         .host_param_mask        = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
 915                                   ISCSI_HOST_INITIATOR_NAME |
 916                                   ISCSI_HOST_NETDEV_NAME,
 917         /* session management */
 918         .create_session         = iscsi_sw_tcp_session_create,
 919         .destroy_session        = iscsi_sw_tcp_session_destroy,
 920         /* connection management */
 921         .create_conn            = iscsi_sw_tcp_conn_create,
 922         .bind_conn              = iscsi_sw_tcp_conn_bind,
 923         .destroy_conn           = iscsi_sw_tcp_conn_destroy,
 924         .set_param              = iscsi_sw_tcp_conn_set_param,
 925         .get_conn_param         = iscsi_sw_tcp_conn_get_param,
 926         .get_session_param      = iscsi_session_get_param,
 927         .start_conn             = iscsi_conn_start,
 928         .stop_conn              = iscsi_sw_tcp_conn_stop,
 929         /* iscsi host params */
 930         .get_host_param         = iscsi_host_get_param,
 931         .set_host_param         = iscsi_host_set_param,
 932         /* IO */
 933         .send_pdu               = iscsi_conn_send_pdu,
 934         .get_stats              = iscsi_sw_tcp_conn_get_stats,
 935         /* iscsi task/cmd helpers */
 936         .init_task              = iscsi_tcp_task_init,
 937         .xmit_task              = iscsi_tcp_task_xmit,
 938         .cleanup_task           = iscsi_tcp_cleanup_task,
 939         /* low level pdu helpers */
 940         .xmit_pdu               = iscsi_sw_tcp_pdu_xmit,
 941         .init_pdu               = iscsi_sw_tcp_pdu_init,
 942         .alloc_pdu              = iscsi_sw_tcp_pdu_alloc,
 943         /* recovery */
 944         .session_recovery_timedout = iscsi_session_recovery_timedout,
 945 };
 946
 947 static int __init iscsi_sw_tcp_init(void)
 948 {
 949         if (iscsi_max_lun < 1) {
 950                 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
 951                        iscsi_max_lun);
 952                 return -EINVAL;
 953         }
 954
 955         iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
 956                                                 &iscsi_sw_tcp_transport);
 957         if (!iscsi_sw_tcp_scsi_transport)
 958                 return -ENODEV;
 959
 960         return 0;
 961 }
 962
 963 static void __exit iscsi_sw_tcp_exit(void)
 964 {
 965         iscsi_unregister_transport(&iscsi_sw_tcp_transport);
 966 }
 967
 968 module_init(iscsi_sw_tcp_init);
 969 module_exit(iscsi_sw_tcp_exit);