drivers/scsi/libiscsi.c

   1 /*
   2  * iSCSI lib functions
   3  *
   4  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   5  * Copyright (C) 2004 - 2006 Mike Christie
   6  * Copyright (C) 2004 - 2005 Dmitry Yusupov
   7  * Copyright (C) 2004 - 2005 Alex Aizman
   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 by
  12  * 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,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  */
  24 #include <linux/types.h>
  25 #include <linux/kfifo.h>
  26 #include <linux/delay.h>
  27 #include <linux/log2.h>
  28 #include <asm/unaligned.h>
  29 #include <net/tcp.h>
  30 #include <scsi/scsi_cmnd.h>
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_tcq.h>
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi.h>
  36 #include <scsi/iscsi_proto.h>
  37 #include <scsi/scsi_transport.h>
  38 #include <scsi/scsi_transport_iscsi.h>
  39 #include <scsi/libiscsi.h>
  40
  41 struct iscsi_session *
  42 class_to_transport_session(struct iscsi_cls_session *cls_session)
  43 {
  44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
  45         return iscsi_hostdata(shost->hostdata);
  46 }
  47 EXPORT_SYMBOL_GPL(class_to_transport_session);
  48
  49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  50 #define SNA32_CHECK 2147483648UL
  51
  52 static int iscsi_sna_lt(u32 n1, u32 n2)
  53 {
  54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  56 }
  57
  58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  59 static int iscsi_sna_lte(u32 n1, u32 n2)
  60 {
  61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  63 }
  64
  65 void
  66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
  67 {
  68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
  69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
  70
  71         /*
  72          * standard specifies this check for when to update expected and
  73          * max sequence numbers
  74          */
  75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
  76                 return;
  77
  78         if (exp_cmdsn != session->exp_cmdsn &&
  79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
  80                 session->exp_cmdsn = exp_cmdsn;
  81
  82         if (max_cmdsn != session->max_cmdsn &&
  83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
  84                 session->max_cmdsn = max_cmdsn;
  85                 /*
  86                  * if the window closed with IO queued, then kick the
  87                  * xmit thread
  88                  */
  89                 if (!list_empty(&session->leadconn->xmitqueue) ||
  90                     !list_empty(&session->leadconn->mgmtqueue))
  91                         scsi_queue_work(session->host,
  92                                         &session->leadconn->xmitwork);
  93         }
  94 }
  95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
  96
  97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
  98                                    struct iscsi_data *hdr)
  99 {
 100         struct iscsi_conn *conn = ctask->conn;
 101
 102         memset(hdr, 0, sizeof(struct iscsi_data));
 103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
 105         ctask->unsol_datasn++;
 106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
 108
 109         hdr->itt = ctask->hdr->itt;
 110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
 112
 113         if (ctask->unsol_count > conn->max_xmit_dlength) {
 114                 hton24(hdr->dlength, conn->max_xmit_dlength);
 115                 ctask->data_count = conn->max_xmit_dlength;
 116                 ctask->unsol_offset += ctask->data_count;
 117                 hdr->flags = 0;
 118         } else {
 119                 hton24(hdr->dlength, ctask->unsol_count);
 120                 ctask->data_count = ctask->unsol_count;
 121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
 122         }
 123 }
 124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
 125
 126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
 127 {
 128         unsigned exp_len = ctask->hdr_len + len;
 129
 130         if (exp_len > ctask->hdr_max) {
 131                 WARN_ON(1);
 132                 return -EINVAL;
 133         }
 134
 135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 136         ctask->hdr_len = exp_len;
 137         return 0;
 138 }
 139
 140 /**
 141  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 142  * @ctask: iscsi cmd task
 143  *
 144  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 145  * fields like dlength or final based on how much data it sends
 146  */
 147 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 148 {
 149         struct iscsi_conn *conn = ctask->conn;
 150         struct iscsi_session *session = conn->session;
 151         struct iscsi_cmd *hdr = ctask->hdr;
 152         struct scsi_cmnd *sc = ctask->sc;
 153         unsigned hdrlength;
 154         int rc;
 155
 156         ctask->hdr_len = 0;
 157         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
 158         if (rc)
 159                 return rc;
 160         hdr->opcode = ISCSI_OP_SCSI_CMD;
 161         hdr->flags = ISCSI_ATTR_SIMPLE;
 162         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 163         hdr->itt = build_itt(ctask->itt, session->age);
 164         hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
 165         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 166         session->cmdsn++;
 167         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 168         memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
 169         if (sc->cmd_len < MAX_COMMAND_SIZE)
 170                 memset(&hdr->cdb[sc->cmd_len], 0,
 171                         MAX_COMMAND_SIZE - sc->cmd_len);
 172
 173         ctask->imm_count = 0;
 174         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 175                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 176                 /*
 177                  * Write counters:
 178                  *
 179                  *      imm_count       bytes to be sent right after
 180                  *                      SCSI PDU Header
 181                  *
 182                  *      unsol_count     bytes(as Data-Out) to be sent
 183                  *                      without R2T ack right after
 184                  *                      immediate data
 185                  *
 186                  *      r2t_data_count  bytes to be sent via R2T ack's
 187                  *
 188                  *      pad_count       bytes to be sent as zero-padding
 189                  */
 190                 ctask->unsol_count = 0;
 191                 ctask->unsol_offset = 0;
 192                 ctask->unsol_datasn = 0;
 193
 194                 if (session->imm_data_en) {
 195                         if (scsi_bufflen(sc) >= session->first_burst)
 196                                 ctask->imm_count = min(session->first_burst,
 197                                                         conn->max_xmit_dlength);
 198                         else
 199                                 ctask->imm_count = min(scsi_bufflen(sc),
 200                                                         conn->max_xmit_dlength);
 201                         hton24(hdr->dlength, ctask->imm_count);
 202                 } else
 203                         zero_data(hdr->dlength);
 204
 205                 if (!session->initial_r2t_en) {
 206                         ctask->unsol_count = min((session->first_burst),
 207                                 (scsi_bufflen(sc))) - ctask->imm_count;
 208                         ctask->unsol_offset = ctask->imm_count;
 209                 }
 210
 211                 if (!ctask->unsol_count)
 212                         /* No unsolicit Data-Out's */
 213                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 214         } else {
 215                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 216                 zero_data(hdr->dlength);
 217
 218                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 219                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 220         }
 221
 222         /* calculate size of additional header segments (AHSs) */
 223         hdrlength = ctask->hdr_len - sizeof(*hdr);
 224
 225         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 226         hdrlength /= ISCSI_PAD_LEN;
 227
 228         WARN_ON(hdrlength >= 256);
 229         hdr->hlength = hdrlength & 0xFF;
 230
 231         if (conn->session->tt->init_cmd_task(conn->ctask))
 232                 return EIO;
 233
 234         conn->scsicmd_pdus_cnt++;
 235         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
 236                 "cmdsn %d win %d]\n",
 237                 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 238                 conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
 239                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 240         return 0;
 241 }
 242
 243 /**
 244  * iscsi_complete_command - return command back to scsi-ml
 245  * @ctask: iscsi cmd task
 246  *
 247  * Must be called with session lock.
 248  * This function returns the scsi command to scsi-ml and returns
 249  * the cmd task to the pool of available cmd tasks.
 250  */
 251 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
 252 {
 253         struct iscsi_conn *conn = ctask->conn;
 254         struct iscsi_session *session = conn->session;
 255         struct scsi_cmnd *sc = ctask->sc;
 256
 257         ctask->state = ISCSI_TASK_COMPLETED;
 258         ctask->sc = NULL;
 259         /* SCSI eh reuses commands to verify us */
 260         sc->SCp.ptr = NULL;
 261         if (conn->ctask == ctask)
 262                 conn->ctask = NULL;
 263         list_del_init(&ctask->running);
 264         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 265         sc->scsi_done(sc);
 266 }
 267
 268 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 269 {
 270         atomic_inc(&ctask->refcount);
 271 }
 272
 273 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 274 {
 275         if (atomic_dec_and_test(&ctask->refcount))
 276                 iscsi_complete_command(ctask);
 277 }
 278
 279 /*
 280  * session lock must be held
 281  */
 282 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 283                          int err)
 284 {
 285         struct scsi_cmnd *sc;
 286
 287         sc = ctask->sc;
 288         if (!sc)
 289                 return;
 290
 291         if (ctask->state == ISCSI_TASK_PENDING)
 292                 /*
 293                  * cmd never made it to the xmit thread, so we should not count
 294                  * the cmd in the sequencing
 295                  */
 296                 conn->session->queued_cmdsn--;
 297         else
 298                 conn->session->tt->cleanup_cmd_task(conn, ctask);
 299
 300         sc->result = err;
 301         scsi_set_resid(sc, scsi_bufflen(sc));
 302         if (conn->ctask == ctask)
 303                 conn->ctask = NULL;
 304         /* release ref from queuecommand */
 305         __iscsi_put_ctask(ctask);
 306 }
 307
 308 /**
 309  * iscsi_free_mgmt_task - return mgmt task back to pool
 310  * @conn: iscsi connection
 311  * @mtask: mtask
 312  *
 313  * Must be called with session lock.
 314  */
 315 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
 316                           struct iscsi_mgmt_task *mtask)
 317 {
 318         list_del_init(&mtask->running);
 319         if (conn->login_mtask == mtask)
 320                 return;
 321
 322         if (conn->ping_mtask == mtask)
 323                 conn->ping_mtask = NULL;
 324         __kfifo_put(conn->session->mgmtpool.queue,
 325                     (void*)&mtask, sizeof(void*));
 326 }
 327 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
 328
 329 static struct iscsi_mgmt_task *
 330 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 331                       char *data, uint32_t data_size)
 332 {
 333         struct iscsi_session *session = conn->session;
 334         struct iscsi_mgmt_task *mtask;
 335
 336         if (session->state == ISCSI_STATE_TERMINATE)
 337                 return NULL;
 338
 339         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 340             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 341                 /*
 342                  * Login and Text are sent serially, in
 343                  * request-followed-by-response sequence.
 344                  * Same mtask can be used. Same ITT must be used.
 345                  * Note that login_mtask is preallocated at conn_create().
 346                  */
 347                 mtask = conn->login_mtask;
 348         else {
 349                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 350                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 351
 352                 if (!__kfifo_get(session->mgmtpool.queue,
 353                                  (void*)&mtask, sizeof(void*)))
 354                         return NULL;
 355         }
 356
 357         if (data_size) {
 358                 memcpy(mtask->data, data, data_size);
 359                 mtask->data_count = data_size;
 360         } else
 361                 mtask->data_count = 0;
 362
 363         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 364         INIT_LIST_HEAD(&mtask->running);
 365         list_add_tail(&mtask->running, &conn->mgmtqueue);
 366         return mtask;
 367 }
 368
 369 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 370                         char *data, uint32_t data_size)
 371 {
 372         struct iscsi_conn *conn = cls_conn->dd_data;
 373         struct iscsi_session *session = conn->session;
 374         int err = 0;
 375
 376         spin_lock_bh(&session->lock);
 377         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 378                 err = -EPERM;
 379         spin_unlock_bh(&session->lock);
 380         scsi_queue_work(session->host, &conn->xmitwork);
 381         return err;
 382 }
 383 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 384
 385 /**
 386  * iscsi_cmd_rsp - SCSI Command Response processing
 387  * @conn: iscsi connection
 388  * @hdr: iscsi header
 389  * @ctask: scsi command task
 390  * @data: cmd data buffer
 391  * @datalen: len of buffer
 392  *
 393  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 394  * then completes the command and task.
 395  **/
 396 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 397                                struct iscsi_cmd_task *ctask, char *data,
 398                                int datalen)
 399 {
 400         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 401         struct iscsi_session *session = conn->session;
 402         struct scsi_cmnd *sc = ctask->sc;
 403
 404         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 405         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 406
 407         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 408
 409         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 410                 sc->result = DID_ERROR << 16;
 411                 goto out;
 412         }
 413
 414         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 415                 uint16_t senselen;
 416
 417                 if (datalen < 2) {
 418 invalid_datalen:
 419                         iscsi_conn_printk(KERN_ERR,  conn,
 420                                          "Got CHECK_CONDITION but invalid data "
 421                                          "buffer size of %d\n", datalen);
 422                         sc->result = DID_BAD_TARGET << 16;
 423                         goto out;
 424                 }
 425
 426                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
 427                 if (datalen < senselen)
 428                         goto invalid_datalen;
 429
 430                 memcpy(sc->sense_buffer, data + 2,
 431                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 432                 debug_scsi("copied %d bytes of sense\n",
 433                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 434         }
 435
 436         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 437                            ISCSI_FLAG_CMD_OVERFLOW)) {
 438                 int res_count = be32_to_cpu(rhdr->residual_count);
 439
 440                 if (res_count > 0 &&
 441                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 442                      res_count <= scsi_bufflen(sc)))
 443                         scsi_set_resid(sc, res_count);
 444                 else
 445                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 446         } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 447                                   ISCSI_FLAG_CMD_BIDI_OVERFLOW))
 448                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 449
 450 out:
 451         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 452                    (long)sc, sc->result, ctask->itt);
 453         conn->scsirsp_pdus_cnt++;
 454
 455         __iscsi_put_ctask(ctask);
 456 }
 457
 458 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 459 {
 460         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 461
 462         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 463         conn->tmfrsp_pdus_cnt++;
 464
 465         if (conn->tmf_state != TMF_QUEUED)
 466                 return;
 467
 468         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 469                 conn->tmf_state = TMF_SUCCESS;
 470         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 471                 conn->tmf_state = TMF_NOT_FOUND;
 472         else
 473                 conn->tmf_state = TMF_FAILED;
 474         wake_up(&conn->ehwait);
 475 }
 476
 477 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 478 {
 479         struct iscsi_nopout hdr;
 480         struct iscsi_mgmt_task *mtask;
 481
 482         if (!rhdr && conn->ping_mtask)
 483                 return;
 484
 485         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 486         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 487         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 488
 489         if (rhdr) {
 490                 memcpy(hdr.lun, rhdr->lun, 8);
 491                 hdr.ttt = rhdr->ttt;
 492                 hdr.itt = RESERVED_ITT;
 493         } else
 494                 hdr.ttt = RESERVED_ITT;
 495
 496         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 497         if (!mtask) {
 498                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 499                 return;
 500         }
 501
 502         /* only track our nops */
 503         if (!rhdr) {
 504                 conn->ping_mtask = mtask;
 505                 conn->last_ping = jiffies;
 506         }
 507         scsi_queue_work(conn->session->host, &conn->xmitwork);
 508 }
 509
 510 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 511                                char *data, int datalen)
 512 {
 513         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 514         struct iscsi_hdr rejected_pdu;
 515         uint32_t itt;
 516
 517         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 518
 519         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 520                 if (ntoh24(reject->dlength) > datalen)
 521                         return ISCSI_ERR_PROTO;
 522
 523                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 524                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 525                         itt = get_itt(rejected_pdu.itt);
 526                         iscsi_conn_printk(KERN_ERR, conn,
 527                                           "itt 0x%x had pdu (op 0x%x) rejected "
 528                                           "due to DataDigest error.\n", itt,
 529                                           rejected_pdu.opcode);
 530                 }
 531         }
 532         return 0;
 533 }
 534
 535 /**
 536  * __iscsi_complete_pdu - complete pdu
 537  * @conn: iscsi conn
 538  * @hdr: iscsi header
 539  * @data: data buffer
 540  * @datalen: len of data buffer
 541  *
 542  * Completes pdu processing by freeing any resources allocated at
 543  * queuecommand or send generic. session lock must be held and verify
 544  * itt must have been called.
 545  */
 546 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 547                                 char *data, int datalen)
 548 {
 549         struct iscsi_session *session = conn->session;
 550         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 551         struct iscsi_cmd_task *ctask;
 552         struct iscsi_mgmt_task *mtask;
 553         uint32_t itt;
 554
 555         conn->last_recv = jiffies;
 556         if (hdr->itt != RESERVED_ITT)
 557                 itt = get_itt(hdr->itt);
 558         else
 559                 itt = ~0U;
 560
 561         if (itt < session->cmds_max) {
 562                 ctask = session->cmds[itt];
 563
 564                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 565                            opcode, conn->id, ctask->itt, datalen);
 566
 567                 switch(opcode) {
 568                 case ISCSI_OP_SCSI_CMD_RSP:
 569                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 570                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 571                                            datalen);
 572                         break;
 573                 case ISCSI_OP_SCSI_DATA_IN:
 574                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 575                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 576                                 conn->scsirsp_pdus_cnt++;
 577                                 __iscsi_put_ctask(ctask);
 578                         }
 579                         break;
 580                 case ISCSI_OP_R2T:
 581                         /* LLD handles this for now */
 582                         break;
 583                 default:
 584                         rc = ISCSI_ERR_BAD_OPCODE;
 585                         break;
 586                 }
 587         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 588                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 589                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 590
 591                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 592                            opcode, conn->id, mtask->itt, datalen);
 593
 594                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 595                 switch(opcode) {
 596                 case ISCSI_OP_LOGOUT_RSP:
 597                         if (datalen) {
 598                                 rc = ISCSI_ERR_PROTO;
 599                                 break;
 600                         }
 601                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 602                         /* fall through */
 603                 case ISCSI_OP_LOGIN_RSP:
 604                 case ISCSI_OP_TEXT_RSP:
 605                         /*
 606                          * login related PDU's exp_statsn is handled in
 607                          * userspace
 608                          */
 609                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 610                                 rc = ISCSI_ERR_CONN_FAILED;
 611                         iscsi_free_mgmt_task(conn, mtask);
 612                         break;
 613                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 614                         if (datalen) {
 615                                 rc = ISCSI_ERR_PROTO;
 616                                 break;
 617                         }
 618
 619                         iscsi_tmf_rsp(conn, hdr);
 620                         iscsi_free_mgmt_task(conn, mtask);
 621                         break;
 622                 case ISCSI_OP_NOOP_IN:
 623                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 624                             datalen) {
 625                                 rc = ISCSI_ERR_PROTO;
 626                                 break;
 627                         }
 628                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 629
 630                         if (conn->ping_mtask != mtask) {
 631                                 /*
 632                                  * If this is not in response to one of our
 633                                  * nops then it must be from userspace.
 634                                  */
 635                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 636                                                    datalen))
 637                                         rc = ISCSI_ERR_CONN_FAILED;
 638                         }
 639                         iscsi_free_mgmt_task(conn, mtask);
 640                         break;
 641                 default:
 642                         rc = ISCSI_ERR_BAD_OPCODE;
 643                         break;
 644                 }
 645         } else if (itt == ~0U) {
 646                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 647
 648                 switch(opcode) {
 649                 case ISCSI_OP_NOOP_IN:
 650                         if (datalen) {
 651                                 rc = ISCSI_ERR_PROTO;
 652                                 break;
 653                         }
 654
 655                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 656                                 break;
 657
 658                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 659                         break;
 660                 case ISCSI_OP_REJECT:
 661                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 662                         break;
 663                 case ISCSI_OP_ASYNC_EVENT:
 664                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 665                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 666                                 rc = ISCSI_ERR_CONN_FAILED;
 667                         break;
 668                 default:
 669                         rc = ISCSI_ERR_BAD_OPCODE;
 670                         break;
 671                 }
 672         } else
 673                 rc = ISCSI_ERR_BAD_ITT;
 674
 675         return rc;
 676 }
 677
 678 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 679                        char *data, int datalen)
 680 {
 681         int rc;
 682
 683         spin_lock(&conn->session->lock);
 684         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 685         spin_unlock(&conn->session->lock);
 686         return rc;
 687 }
 688 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 689
 690 /* verify itt (itt encoding: age+cid+itt) */
 691 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 692                      uint32_t *ret_itt)
 693 {
 694         struct iscsi_session *session = conn->session;
 695         struct iscsi_cmd_task *ctask;
 696         uint32_t itt;
 697
 698         if (hdr->itt != RESERVED_ITT) {
 699                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
 700                     (session->age << ISCSI_AGE_SHIFT)) {
 701                         iscsi_conn_printk(KERN_ERR, conn,
 702                                           "received itt %x expected session "
 703                                           "age (%x)\n", (__force u32)hdr->itt,
 704                                           session->age & ISCSI_AGE_MASK);
 705                         return ISCSI_ERR_BAD_ITT;
 706                 }
 707
 708                 itt = get_itt(hdr->itt);
 709         } else
 710                 itt = ~0U;
 711
 712         if (itt < session->cmds_max) {
 713                 ctask = session->cmds[itt];
 714
 715                 if (!ctask->sc) {
 716                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
 717                                           "with itt 0x%x\n", ctask->itt);
 718                         /* force drop */
 719                         return ISCSI_ERR_NO_SCSI_CMD;
 720                 }
 721
 722                 if (ctask->sc->SCp.phase != session->age) {
 723                         iscsi_conn_printk(KERN_ERR, conn,
 724                                           "iscsi: ctask's session age %d, "
 725                                           "expected %d\n", ctask->sc->SCp.phase,
 726                                           session->age);
 727                         return ISCSI_ERR_SESSION_FAILED;
 728                 }
 729         }
 730
 731         *ret_itt = itt;
 732         return 0;
 733 }
 734 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 735
 736 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 737 {
 738         struct iscsi_session *session = conn->session;
 739         unsigned long flags;
 740
 741         spin_lock_irqsave(&session->lock, flags);
 742         if (session->state == ISCSI_STATE_FAILED) {
 743                 spin_unlock_irqrestore(&session->lock, flags);
 744                 return;
 745         }
 746
 747         if (conn->stop_stage == 0)
 748                 session->state = ISCSI_STATE_FAILED;
 749         spin_unlock_irqrestore(&session->lock, flags);
 750         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 751         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 752         iscsi_conn_error(conn->cls_conn, err);
 753 }
 754 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 755
 756 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 757                              struct iscsi_mgmt_task *mtask)
 758 {
 759         struct iscsi_session *session = conn->session;
 760         struct iscsi_hdr *hdr = mtask->hdr;
 761         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 762
 763         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 764             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 765                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 766         /*
 767          * pre-format CmdSN for outgoing PDU.
 768          */
 769         nop->cmdsn = cpu_to_be32(session->cmdsn);
 770         if (hdr->itt != RESERVED_ITT) {
 771                 hdr->itt = build_itt(mtask->itt, session->age);
 772                 /*
 773                  * TODO: We always use immediate, so we never hit this.
 774                  * If we start to send tmfs or nops as non-immediate then
 775                  * we should start checking the cmdsn numbers for mgmt tasks.
 776                  */
 777                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 778                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 779                         session->queued_cmdsn++;
 780                         session->cmdsn++;
 781                 }
 782         }
 783
 784         if (session->tt->init_mgmt_task)
 785                 session->tt->init_mgmt_task(conn, mtask);
 786
 787         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 788                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 789                    mtask->data_count);
 790 }
 791
 792 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 793 {
 794         struct iscsi_hdr *hdr = conn->mtask->hdr;
 795         int rc;
 796
 797         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 798                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 799         spin_unlock_bh(&conn->session->lock);
 800
 801         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 802         spin_lock_bh(&conn->session->lock);
 803         if (rc)
 804                 return rc;
 805
 806         /* done with this in-progress mtask */
 807         conn->mtask = NULL;
 808         return 0;
 809 }
 810
 811 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 812 {
 813         struct iscsi_session *session = conn->session;
 814
 815         /*
 816          * Check for iSCSI window and take care of CmdSN wrap-around
 817          */
 818         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 819                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 820                            "CmdSN %u/%u\n", session->exp_cmdsn,
 821                            session->max_cmdsn, session->cmdsn,
 822                            session->queued_cmdsn);
 823                 return -ENOSPC;
 824         }
 825         return 0;
 826 }
 827
 828 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 829 {
 830         struct iscsi_cmd_task *ctask = conn->ctask;
 831         int rc;
 832
 833         __iscsi_get_ctask(ctask);
 834         spin_unlock_bh(&conn->session->lock);
 835         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 836         spin_lock_bh(&conn->session->lock);
 837         __iscsi_put_ctask(ctask);
 838         if (!rc)
 839                 /* done with this ctask */
 840                 conn->ctask = NULL;
 841         return rc;
 842 }
 843
 844 /**
 845  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 846  * @ctask: ctask to requeue
 847  *
 848  * LLDs that need to run a ctask from the session workqueue should call
 849  * this. The session lock must be held.
 850  */
 851 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 852 {
 853         struct iscsi_conn *conn = ctask->conn;
 854
 855         list_move_tail(&ctask->running, &conn->requeue);
 856         scsi_queue_work(conn->session->host, &conn->xmitwork);
 857 }
 858 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 859
 860 /**
 861  * iscsi_data_xmit - xmit any command into the scheduled connection
 862  * @conn: iscsi connection
 863  *
 864  * Notes:
 865  *      The function can return -EAGAIN in which case the caller must
 866  *      re-schedule it again later or recover. '0' return code means
 867  *      successful xmit.
 868  **/
 869 static int iscsi_data_xmit(struct iscsi_conn *conn)
 870 {
 871         int rc = 0;
 872
 873         spin_lock_bh(&conn->session->lock);
 874         if (unlikely(conn->suspend_tx)) {
 875                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 876                 spin_unlock_bh(&conn->session->lock);
 877                 return -ENODATA;
 878         }
 879
 880         if (conn->ctask) {
 881                 rc = iscsi_xmit_ctask(conn);
 882                 if (rc)
 883                         goto again;
 884         }
 885
 886         if (conn->mtask) {
 887                 rc = iscsi_xmit_mtask(conn);
 888                 if (rc)
 889                         goto again;
 890         }
 891
 892         /*
 893          * process mgmt pdus like nops before commands since we should
 894          * only have one nop-out as a ping from us and targets should not
 895          * overflow us with nop-ins
 896          */
 897 check_mgmt:
 898         while (!list_empty(&conn->mgmtqueue)) {
 899                 conn->mtask = list_entry(conn->mgmtqueue.next,
 900                                          struct iscsi_mgmt_task, running);
 901                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 902                         iscsi_free_mgmt_task(conn, conn->mtask);
 903                         conn->mtask = NULL;
 904                         continue;
 905                 }
 906
 907                 iscsi_prep_mtask(conn, conn->mtask);
 908                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
 909                 rc = iscsi_xmit_mtask(conn);
 910                 if (rc)
 911                         goto again;
 912         }
 913
 914         /* process pending command queue */
 915         while (!list_empty(&conn->xmitqueue)) {
 916                 if (conn->tmf_state == TMF_QUEUED)
 917                         break;
 918
 919                 conn->ctask = list_entry(conn->xmitqueue.next,
 920                                          struct iscsi_cmd_task, running);
 921                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 922                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
 923                         continue;
 924                 }
 925                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
 926                         fail_command(conn, conn->ctask, DID_ABORT << 16);
 927                         continue;
 928                 }
 929
 930                 conn->ctask->state = ISCSI_TASK_RUNNING;
 931                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 932                 rc = iscsi_xmit_ctask(conn);
 933                 if (rc)
 934                         goto again;
 935                 /*
 936                  * we could continuously get new ctask requests so
 937                  * we need to check the mgmt queue for nops that need to
 938                  * be sent to aviod starvation
 939                  */
 940                 if (!list_empty(&conn->mgmtqueue))
 941                         goto check_mgmt;
 942         }
 943
 944         while (!list_empty(&conn->requeue)) {
 945                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
 946                         break;
 947
 948                 /*
 949                  * we always do fastlogout - conn stop code will clean up.
 950                  */
 951                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 952                         break;
 953
 954                 conn->ctask = list_entry(conn->requeue.next,
 955                                          struct iscsi_cmd_task, running);
 956                 conn->ctask->state = ISCSI_TASK_RUNNING;
 957                 list_move_tail(conn->requeue.next, &conn->run_list);
 958                 rc = iscsi_xmit_ctask(conn);
 959                 if (rc)
 960                         goto again;
 961                 if (!list_empty(&conn->mgmtqueue))
 962                         goto check_mgmt;
 963         }
 964         spin_unlock_bh(&conn->session->lock);
 965         return -ENODATA;
 966
 967 again:
 968         if (unlikely(conn->suspend_tx))
 969                 rc = -ENODATA;
 970         spin_unlock_bh(&conn->session->lock);
 971         return rc;
 972 }
 973
 974 static void iscsi_xmitworker(struct work_struct *work)
 975 {
 976         struct iscsi_conn *conn =
 977                 container_of(work, struct iscsi_conn, xmitwork);
 978         int rc;
 979         /*
 980          * serialize Xmit worker on a per-connection basis.
 981          */
 982         do {
 983                 rc = iscsi_data_xmit(conn);
 984         } while (rc >= 0 || rc == -EAGAIN);
 985 }
 986
 987 enum {
 988         FAILURE_BAD_HOST = 1,
 989         FAILURE_SESSION_FAILED,
 990         FAILURE_SESSION_FREED,
 991         FAILURE_WINDOW_CLOSED,
 992         FAILURE_OOM,
 993         FAILURE_SESSION_TERMINATE,
 994         FAILURE_SESSION_IN_RECOVERY,
 995         FAILURE_SESSION_RECOVERY_TIMEOUT,
 996         FAILURE_SESSION_LOGGING_OUT,
 997         FAILURE_SESSION_NOT_READY,
 998 };
 999
1000 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1001 {
1002         struct Scsi_Host *host;
1003         int reason = 0;
1004         struct iscsi_session *session;
1005         struct iscsi_conn *conn;
1006         struct iscsi_cmd_task *ctask = NULL;
1007
1008         sc->scsi_done = done;
1009         sc->result = 0;
1010         sc->SCp.ptr = NULL;
1011
1012         host = sc->device->host;
1013         spin_unlock(host->host_lock);
1014
1015         session = iscsi_hostdata(host->hostdata);
1016         spin_lock(&session->lock);
1017
1018         reason = iscsi_session_chkready(session_to_cls(session));
1019         if (reason) {
1020                 sc->result = reason;
1021                 goto fault;
1022         }
1023
1024         /*
1025          * ISCSI_STATE_FAILED is a temp. state. The recovery
1026          * code will decide what is best to do with command queued
1027          * during this time
1028          */
1029         if (session->state != ISCSI_STATE_LOGGED_IN &&
1030             session->state != ISCSI_STATE_FAILED) {
1031                 /*
1032                  * to handle the race between when we set the recovery state
1033                  * and block the session we requeue here (commands could
1034                  * be entering our queuecommand while a block is starting
1035                  * up because the block code is not locked)
1036                  */
1037                 switch (session->state) {
1038                 case ISCSI_STATE_IN_RECOVERY:
1039                         reason = FAILURE_SESSION_IN_RECOVERY;
1040                         sc->result = DID_IMM_RETRY << 16;
1041                         break;
1042                 case ISCSI_STATE_LOGGING_OUT:
1043                         reason = FAILURE_SESSION_LOGGING_OUT;
1044                         sc->result = DID_IMM_RETRY << 16;
1045                         break;
1046                 case ISCSI_STATE_RECOVERY_FAILED:
1047                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1048                         sc->result = DID_NO_CONNECT << 16;
1049                         break;
1050                 case ISCSI_STATE_TERMINATE:
1051                         reason = FAILURE_SESSION_TERMINATE;
1052                         sc->result = DID_NO_CONNECT << 16;
1053                         break;
1054                 default:
1055                         reason = FAILURE_SESSION_FREED;
1056                         sc->result = DID_NO_CONNECT << 16;
1057                 }
1058                 goto fault;
1059         }
1060
1061         conn = session->leadconn;
1062         if (!conn) {
1063                 reason = FAILURE_SESSION_FREED;
1064                 sc->result = DID_NO_CONNECT << 16;
1065                 goto fault;
1066         }
1067
1068         if (iscsi_check_cmdsn_window_closed(conn)) {
1069                 reason = FAILURE_WINDOW_CLOSED;
1070                 goto reject;
1071         }
1072
1073         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1074                          sizeof(void*))) {
1075                 reason = FAILURE_OOM;
1076                 goto reject;
1077         }
1078         session->queued_cmdsn++;
1079
1080         sc->SCp.phase = session->age;
1081         sc->SCp.ptr = (char *)ctask;
1082
1083         atomic_set(&ctask->refcount, 1);
1084         ctask->state = ISCSI_TASK_PENDING;
1085         ctask->conn = conn;
1086         ctask->sc = sc;
1087         INIT_LIST_HEAD(&ctask->running);
1088
1089         list_add_tail(&ctask->running, &conn->xmitqueue);
1090         spin_unlock(&session->lock);
1091
1092         scsi_queue_work(host, &conn->xmitwork);
1093         spin_lock(host->host_lock);
1094         return 0;
1095
1096 reject:
1097         spin_unlock(&session->lock);
1098         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1099         spin_lock(host->host_lock);
1100         return SCSI_MLQUEUE_HOST_BUSY;
1101
1102 fault:
1103         spin_unlock(&session->lock);
1104         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1105         scsi_set_resid(sc, scsi_bufflen(sc));
1106         sc->scsi_done(sc);
1107         spin_lock(host->host_lock);
1108         return 0;
1109 }
1110 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1111
1112 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1113 {
1114         if (depth > ISCSI_MAX_CMD_PER_LUN)
1115                 depth = ISCSI_MAX_CMD_PER_LUN;
1116         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1117         return sdev->queue_depth;
1118 }
1119 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1120
1121 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1122 {
1123         struct iscsi_session *session = class_to_transport_session(cls_session);
1124
1125         spin_lock_bh(&session->lock);
1126         if (session->state != ISCSI_STATE_LOGGED_IN) {
1127                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1128                 if (session->leadconn)
1129                         wake_up(&session->leadconn->ehwait);
1130         }
1131         spin_unlock_bh(&session->lock);
1132 }
1133 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1134
1135 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1136 {
1137         struct Scsi_Host *host = sc->device->host;
1138         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1139         struct iscsi_conn *conn = session->leadconn;
1140
1141         mutex_lock(&session->eh_mutex);
1142         spin_lock_bh(&session->lock);
1143         if (session->state == ISCSI_STATE_TERMINATE) {
1144 failed:
1145                 debug_scsi("failing host reset: session terminated "
1146                            "[CID %d age %d]\n", conn->id, session->age);
1147                 spin_unlock_bh(&session->lock);
1148                 mutex_unlock(&session->eh_mutex);
1149                 return FAILED;
1150         }
1151
1152         spin_unlock_bh(&session->lock);
1153         mutex_unlock(&session->eh_mutex);
1154         /*
1155          * we drop the lock here but the leadconn cannot be destoyed while
1156          * we are in the scsi eh
1157          */
1158         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1159
1160         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1161         wait_event_interruptible(conn->ehwait,
1162                                  session->state == ISCSI_STATE_TERMINATE ||
1163                                  session->state == ISCSI_STATE_LOGGED_IN ||
1164                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1165         if (signal_pending(current))
1166                 flush_signals(current);
1167
1168         mutex_lock(&session->eh_mutex);
1169         spin_lock_bh(&session->lock);
1170         if (session->state == ISCSI_STATE_LOGGED_IN)
1171                 iscsi_session_printk(KERN_INFO, session,
1172                                      "host reset succeeded\n");
1173         else
1174                 goto failed;
1175         spin_unlock_bh(&session->lock);
1176         mutex_unlock(&session->eh_mutex);
1177         return SUCCESS;
1178 }
1179 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1180
1181 static void iscsi_tmf_timedout(unsigned long data)
1182 {
1183         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1184         struct iscsi_session *session = conn->session;
1185
1186         spin_lock(&session->lock);
1187         if (conn->tmf_state == TMF_QUEUED) {
1188                 conn->tmf_state = TMF_TIMEDOUT;
1189                 debug_scsi("tmf timedout\n");
1190                 /* unblock eh_abort() */
1191                 wake_up(&conn->ehwait);
1192         }
1193         spin_unlock(&session->lock);
1194 }
1195
1196 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1197                                    struct iscsi_tm *hdr, int age,
1198                                    int timeout)
1199 {
1200         struct iscsi_session *session = conn->session;
1201         struct iscsi_mgmt_task *mtask;
1202
1203         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1204                                       NULL, 0);
1205         if (!mtask) {
1206                 spin_unlock_bh(&session->lock);
1207                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1208                 spin_lock_bh(&session->lock);
1209                 debug_scsi("tmf exec failure\n");
1210                 return -EPERM;
1211         }
1212         conn->tmfcmd_pdus_cnt++;
1213         conn->tmf_timer.expires = timeout * HZ + jiffies;
1214         conn->tmf_timer.function = iscsi_tmf_timedout;
1215         conn->tmf_timer.data = (unsigned long)conn;
1216         add_timer(&conn->tmf_timer);
1217         debug_scsi("tmf set timeout\n");
1218
1219         spin_unlock_bh(&session->lock);
1220         mutex_unlock(&session->eh_mutex);
1221         scsi_queue_work(session->host, &conn->xmitwork);
1222
1223         /*
1224          * block eh thread until:
1225          *
1226          * 1) tmf response
1227          * 2) tmf timeout
1228          * 3) session is terminated or restarted or userspace has
1229          * given up on recovery
1230          */
1231         wait_event_interruptible(conn->ehwait, age != session->age ||
1232                                  session->state != ISCSI_STATE_LOGGED_IN ||
1233                                  conn->tmf_state != TMF_QUEUED);
1234         if (signal_pending(current))
1235                 flush_signals(current);
1236         del_timer_sync(&conn->tmf_timer);
1237
1238         mutex_lock(&session->eh_mutex);
1239         spin_lock_bh(&session->lock);
1240         /* if the session drops it will clean up the mtask */
1241         if (age != session->age ||
1242             session->state != ISCSI_STATE_LOGGED_IN)
1243                 return -ENOTCONN;
1244         return 0;
1245 }
1246
1247 /*
1248  * Fail commands. session lock held and recv side suspended and xmit
1249  * thread flushed
1250  */
1251 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1252                               int error)
1253 {
1254         struct iscsi_cmd_task *ctask, *tmp;
1255
1256         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1257                 conn->ctask = NULL;
1258
1259         /* flush pending */
1260         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1261                 if (lun == ctask->sc->device->lun || lun == -1) {
1262                         debug_scsi("failing pending sc %p itt 0x%x\n",
1263                                    ctask->sc, ctask->itt);
1264                         fail_command(conn, ctask, error << 16);
1265                 }
1266         }
1267
1268         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1269                 if (lun == ctask->sc->device->lun || lun == -1) {
1270                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1271                                    ctask->sc, ctask->itt);
1272                         fail_command(conn, ctask, error << 16);
1273                 }
1274         }
1275
1276         /* fail all other running */
1277         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1278                 if (lun == ctask->sc->device->lun || lun == -1) {
1279                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1280                                    ctask->sc, ctask->itt);
1281                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1282                 }
1283         }
1284 }
1285
1286 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1287 {
1288         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1289         scsi_flush_work(conn->session->host);
1290 }
1291
1292 static void iscsi_start_tx(struct iscsi_conn *conn)
1293 {
1294         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1295         scsi_queue_work(conn->session->host, &conn->xmitwork);
1296 }
1297
1298 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1299 {
1300         struct iscsi_cls_session *cls_session;
1301         struct iscsi_session *session;
1302         struct iscsi_conn *conn;
1303         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1304
1305         cls_session = starget_to_session(scsi_target(scmd->device));
1306         session = class_to_transport_session(cls_session);
1307
1308         debug_scsi("scsi cmd %p timedout\n", scmd);
1309
1310         spin_lock(&session->lock);
1311         if (session->state != ISCSI_STATE_LOGGED_IN) {
1312                 /*
1313                  * We are probably in the middle of iscsi recovery so let
1314                  * that complete and handle the error.
1315                  */
1316                 rc = EH_RESET_TIMER;
1317                 goto done;
1318         }
1319
1320         conn = session->leadconn;
1321         if (!conn) {
1322                 /* In the middle of shuting down */
1323                 rc = EH_RESET_TIMER;
1324                 goto done;
1325         }
1326
1327         if (!conn->recv_timeout && !conn->ping_timeout)
1328                 goto done;
1329         /*
1330          * if the ping timedout then we are in the middle of cleaning up
1331          * and can let the iscsi eh handle it
1332          */
1333         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1334                             (conn->ping_timeout * HZ), jiffies))
1335                 rc = EH_RESET_TIMER;
1336         /*
1337          * if we are about to check the transport then give the command
1338          * more time
1339          */
1340         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1341                            jiffies))
1342                 rc = EH_RESET_TIMER;
1343         /* if in the middle of checking the transport then give us more time */
1344         if (conn->ping_mtask)
1345                 rc = EH_RESET_TIMER;
1346 done:
1347         spin_unlock(&session->lock);
1348         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1349         return rc;
1350 }
1351
1352 static void iscsi_check_transport_timeouts(unsigned long data)
1353 {
1354         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1355         struct iscsi_session *session = conn->session;
1356         unsigned long timeout, next_timeout = 0, last_recv;
1357
1358         spin_lock(&session->lock);
1359         if (session->state != ISCSI_STATE_LOGGED_IN)
1360                 goto done;
1361
1362         timeout = conn->recv_timeout;
1363         if (!timeout)
1364                 goto done;
1365
1366         timeout *= HZ;
1367         last_recv = conn->last_recv;
1368         if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
1369                            jiffies)) {
1370                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1371                                   "expired, last rx %lu, last ping %lu, "
1372                                   "now %lu\n", conn->ping_timeout, last_recv,
1373                                   conn->last_ping, jiffies);
1374                 spin_unlock(&session->lock);
1375                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1376                 return;
1377         }
1378
1379         if (time_before_eq(last_recv + timeout, jiffies)) {
1380                 if (time_before_eq(conn->last_ping, last_recv)) {
1381                         /* send a ping to try to provoke some traffic */
1382                         debug_scsi("Sending nopout as ping on conn %p\n", conn);
1383                         iscsi_send_nopout(conn, NULL);
1384                 }
1385                 next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
1386         } else
1387                 next_timeout = last_recv + timeout;
1388
1389         debug_scsi("Setting next tmo %lu\n", next_timeout);
1390         mod_timer(&conn->transport_timer, next_timeout);
1391 done:
1392         spin_unlock(&session->lock);
1393 }
1394
1395 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1396                                       struct iscsi_tm *hdr)
1397 {
1398         memset(hdr, 0, sizeof(*hdr));
1399         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1400         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1401         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1402         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1403         hdr->rtt = ctask->hdr->itt;
1404         hdr->refcmdsn = ctask->hdr->cmdsn;
1405 }
1406
1407 int iscsi_eh_abort(struct scsi_cmnd *sc)
1408 {
1409         struct Scsi_Host *host = sc->device->host;
1410         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1411         struct iscsi_conn *conn;
1412         struct iscsi_cmd_task *ctask;
1413         struct iscsi_tm *hdr;
1414         int rc, age;
1415
1416         mutex_lock(&session->eh_mutex);
1417         spin_lock_bh(&session->lock);
1418         /*
1419          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1420          * got the command.
1421          */
1422         if (!sc->SCp.ptr) {
1423                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1424                 spin_unlock_bh(&session->lock);
1425                 mutex_unlock(&session->eh_mutex);
1426                 return SUCCESS;
1427         }
1428
1429         /*
1430          * If we are not logged in or we have started a new session
1431          * then let the host reset code handle this
1432          */
1433         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1434             sc->SCp.phase != session->age) {
1435                 spin_unlock_bh(&session->lock);
1436                 mutex_unlock(&session->eh_mutex);
1437                 return FAILED;
1438         }
1439
1440         conn = session->leadconn;
1441         conn->eh_abort_cnt++;
1442         age = session->age;
1443
1444         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1445         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1446
1447         /* ctask completed before time out */
1448         if (!ctask->sc) {
1449                 debug_scsi("sc completed while abort in progress\n");
1450                 goto success;
1451         }
1452
1453         if (ctask->state == ISCSI_TASK_PENDING) {
1454                 fail_command(conn, ctask, DID_ABORT << 16);
1455                 goto success;
1456         }
1457
1458         /* only have one tmf outstanding at a time */
1459         if (conn->tmf_state != TMF_INITIAL)
1460                 goto failed;
1461         conn->tmf_state = TMF_QUEUED;
1462
1463         hdr = &conn->tmhdr;
1464         iscsi_prep_abort_task_pdu(ctask, hdr);
1465
1466         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1467                 rc = FAILED;
1468                 goto failed;
1469         }
1470
1471         switch (conn->tmf_state) {
1472         case TMF_SUCCESS:
1473                 spin_unlock_bh(&session->lock);
1474                 iscsi_suspend_tx(conn);
1475                 /*
1476                  * clean up task if aborted. grab the recv lock as a writer
1477                  */
1478                 write_lock_bh(conn->recv_lock);
1479                 spin_lock(&session->lock);
1480                 fail_command(conn, ctask, DID_ABORT << 16);
1481                 conn->tmf_state = TMF_INITIAL;
1482                 spin_unlock(&session->lock);
1483                 write_unlock_bh(conn->recv_lock);
1484                 iscsi_start_tx(conn);
1485                 goto success_unlocked;
1486         case TMF_TIMEDOUT:
1487                 spin_unlock_bh(&session->lock);
1488                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1489                 goto failed_unlocked;
1490         case TMF_NOT_FOUND:
1491                 if (!sc->SCp.ptr) {
1492                         conn->tmf_state = TMF_INITIAL;
1493                         /* ctask completed before tmf abort response */
1494                         debug_scsi("sc completed while abort in progress\n");
1495                         goto success;
1496                 }
1497                 /* fall through */
1498         default:
1499                 conn->tmf_state = TMF_INITIAL;
1500                 goto failed;
1501         }
1502
1503 success:
1504         spin_unlock_bh(&session->lock);
1505 success_unlocked:
1506         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1507         mutex_unlock(&session->eh_mutex);
1508         return SUCCESS;
1509
1510 failed:
1511         spin_unlock_bh(&session->lock);
1512 failed_unlocked:
1513         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1514                     ctask ? ctask->itt : 0);
1515         mutex_unlock(&session->eh_mutex);
1516         return FAILED;
1517 }
1518 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1519
1520 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1521 {
1522         memset(hdr, 0, sizeof(*hdr));
1523         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1524         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1525         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1526         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1527         hdr->rtt = RESERVED_ITT;
1528 }
1529
1530 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1531 {
1532         struct Scsi_Host *host = sc->device->host;
1533         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1534         struct iscsi_conn *conn;
1535         struct iscsi_tm *hdr;
1536         int rc = FAILED;
1537
1538         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1539
1540         mutex_lock(&session->eh_mutex);
1541         spin_lock_bh(&session->lock);
1542         /*
1543          * Just check if we are not logged in. We cannot check for
1544          * the phase because the reset could come from a ioctl.
1545          */
1546         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1547                 goto unlock;
1548         conn = session->leadconn;
1549
1550         /* only have one tmf outstanding at a time */
1551         if (conn->tmf_state != TMF_INITIAL)
1552                 goto unlock;
1553         conn->tmf_state = TMF_QUEUED;
1554
1555         hdr = &conn->tmhdr;
1556         iscsi_prep_lun_reset_pdu(sc, hdr);
1557
1558         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1559                                     session->lu_reset_timeout)) {
1560                 rc = FAILED;
1561                 goto unlock;
1562         }
1563
1564         switch (conn->tmf_state) {
1565         case TMF_SUCCESS:
1566                 break;
1567         case TMF_TIMEDOUT:
1568                 spin_unlock_bh(&session->lock);
1569                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1570                 goto done;
1571         default:
1572                 conn->tmf_state = TMF_INITIAL;
1573                 goto unlock;
1574         }
1575
1576         rc = SUCCESS;
1577         spin_unlock_bh(&session->lock);
1578
1579         iscsi_suspend_tx(conn);
1580         /* need to grab the recv lock then session lock */
1581         write_lock_bh(conn->recv_lock);
1582         spin_lock(&session->lock);
1583         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1584         conn->tmf_state = TMF_INITIAL;
1585         spin_unlock(&session->lock);
1586         write_unlock_bh(conn->recv_lock);
1587
1588         iscsi_start_tx(conn);
1589         goto done;
1590
1591 unlock:
1592         spin_unlock_bh(&session->lock);
1593 done:
1594         debug_scsi("iscsi_eh_device_reset %s\n",
1595                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1596         mutex_unlock(&session->eh_mutex);
1597         return rc;
1598 }
1599 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1600
1601 /*
1602  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1603  * should be accessed via kfifo_{get,put} on q->queue.
1604  * Optionally, the caller can obtain the array of object pointers
1605  * by passing in a non-NULL @items pointer
1606  */
1607 int
1608 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1609 {
1610         int i, num_arrays = 1;
1611
1612         memset(q, 0, sizeof(*q));
1613
1614         q->max = max;
1615
1616         /* If the user passed an items pointer, he wants a copy of
1617          * the array. */
1618         if (items)
1619                 num_arrays++;
1620         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1621         if (q->pool == NULL)
1622                 goto enomem;
1623
1624         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1625                               GFP_KERNEL, NULL);
1626         if (q->queue == ERR_PTR(-ENOMEM))
1627                 goto enomem;
1628
1629         for (i = 0; i < max; i++) {
1630                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1631                 if (q->pool[i] == NULL) {
1632                         q->max = i;
1633                         goto enomem;
1634                 }
1635                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1636         }
1637
1638         if (items) {
1639                 *items = q->pool + max;
1640                 memcpy(*items, q->pool, max * sizeof(void *));
1641         }
1642
1643         return 0;
1644
1645 enomem:
1646         iscsi_pool_free(q);
1647         return -ENOMEM;
1648 }
1649 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1650
1651 void iscsi_pool_free(struct iscsi_pool *q)
1652 {
1653         int i;
1654
1655         for (i = 0; i < q->max; i++)
1656                 kfree(q->pool[i]);
1657         if (q->pool)
1658                 kfree(q->pool);
1659 }
1660 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1661
1662 /*
1663  * iSCSI Session's hostdata organization:
1664  *
1665  *    *------------------* <== hostdata_session(host->hostdata)
1666  *    | ptr to class sess|
1667  *    |------------------| <== iscsi_hostdata(host->hostdata)
1668  *    | iscsi_session    |
1669  *    *------------------*
1670  */
1671
1672 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1673                                  _sz % sizeof(unsigned long))
1674
1675 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1676
1677 /**
1678  * iscsi_session_setup - create iscsi cls session and host and session
1679  * @scsit: scsi transport template
1680  * @iscsit: iscsi transport template
1681  * @cmds_max: scsi host can queue
1682  * @qdepth: scsi host cmds per lun
1683  * @cmd_task_size: LLD ctask private data size
1684  * @mgmt_task_size: LLD mtask private data size
1685  * @initial_cmdsn: initial CmdSN
1686  * @hostno: host no allocated
1687  *
1688  * This can be used by software iscsi_transports that allocate
1689  * a session per scsi host.
1690  **/
1691 struct iscsi_cls_session *
1692 iscsi_session_setup(struct iscsi_transport *iscsit,
1693                     struct scsi_transport_template *scsit,
1694                     uint16_t cmds_max, uint16_t qdepth,
1695                     int cmd_task_size, int mgmt_task_size,
1696                     uint32_t initial_cmdsn, uint32_t *hostno)
1697 {
1698         struct Scsi_Host *shost;
1699         struct iscsi_session *session;
1700         struct iscsi_cls_session *cls_session;
1701         int cmd_i;
1702
1703         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1704                 if (qdepth != 0)
1705                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1706                               "Queue depth must be between 1 and %d.\n",
1707                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1708                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1709         }
1710
1711         if (!is_power_of_2(cmds_max) || cmds_max >= ISCSI_MGMT_ITT_OFFSET ||
1712             cmds_max < 2) {
1713                 if (cmds_max != 0)
1714                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1715                                "can_queue must be a power of 2 and between "
1716                                "2 and %d - setting to %d.\n", cmds_max,
1717                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1718                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1719         }
1720
1721         shost = scsi_host_alloc(iscsit->host_template,
1722                                 hostdata_privsize(sizeof(*session)));
1723         if (!shost)
1724                 return NULL;
1725
1726         /* the iscsi layer takes one task for reserve */
1727         shost->can_queue = cmds_max - 1;
1728         shost->cmd_per_lun = qdepth;
1729         shost->max_id = 1;
1730         shost->max_channel = 0;
1731         shost->max_lun = iscsit->max_lun;
1732         shost->max_cmd_len = iscsit->max_cmd_len;
1733         shost->transportt = scsit;
1734         shost->transportt->create_work_queue = 1;
1735         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1736         *hostno = shost->host_no;
1737
1738         session = iscsi_hostdata(shost->hostdata);
1739         memset(session, 0, sizeof(struct iscsi_session));
1740         session->host = shost;
1741         session->state = ISCSI_STATE_FREE;
1742         session->fast_abort = 1;
1743         session->lu_reset_timeout = 15;
1744         session->abort_timeout = 10;
1745         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1746         session->cmds_max = cmds_max;
1747         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1748         session->exp_cmdsn = initial_cmdsn + 1;
1749         session->max_cmdsn = initial_cmdsn + 1;
1750         session->max_r2t = 1;
1751         session->tt = iscsit;
1752         mutex_init(&session->eh_mutex);
1753
1754         /* initialize SCSI PDU commands pool */
1755         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1756                             (void***)&session->cmds,
1757                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1758                 goto cmdpool_alloc_fail;
1759
1760         /* pre-format cmds pool with ITT */
1761         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1762                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1763
1764                 if (cmd_task_size)
1765                         ctask->dd_data = &ctask[1];
1766                 ctask->itt = cmd_i;
1767                 INIT_LIST_HEAD(&ctask->running);
1768         }
1769
1770         spin_lock_init(&session->lock);
1771
1772         /* initialize immediate command pool */
1773         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1774                            (void***)&session->mgmt_cmds,
1775                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1776                 goto mgmtpool_alloc_fail;
1777
1778
1779         /* pre-format immediate cmds pool with ITT */
1780         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1781                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1782
1783                 if (mgmt_task_size)
1784                         mtask->dd_data = &mtask[1];
1785                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1786                 INIT_LIST_HEAD(&mtask->running);
1787         }
1788
1789         if (scsi_add_host(shost, NULL))
1790                 goto add_host_fail;
1791
1792         if (!try_module_get(iscsit->owner))
1793                 goto cls_session_fail;
1794
1795         cls_session = iscsi_create_session(shost, iscsit, 0);
1796         if (!cls_session)
1797                 goto module_put;
1798         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1799
1800         return cls_session;
1801
1802 module_put:
1803         module_put(iscsit->owner);
1804 cls_session_fail:
1805         scsi_remove_host(shost);
1806 add_host_fail:
1807         iscsi_pool_free(&session->mgmtpool);
1808 mgmtpool_alloc_fail:
1809         iscsi_pool_free(&session->cmdpool);
1810 cmdpool_alloc_fail:
1811         scsi_host_put(shost);
1812         return NULL;
1813 }
1814 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1815
1816 /**
1817  * iscsi_session_teardown - destroy session, host, and cls_session
1818  * shost: scsi host
1819  *
1820  * This can be used by software iscsi_transports that allocate
1821  * a session per scsi host.
1822  **/
1823 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1824 {
1825         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1826         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1827         struct module *owner = cls_session->transport->owner;
1828
1829         iscsi_remove_session(cls_session);
1830         scsi_remove_host(shost);
1831
1832         iscsi_pool_free(&session->mgmtpool);
1833         iscsi_pool_free(&session->cmdpool);
1834
1835         kfree(session->password);
1836         kfree(session->password_in);
1837         kfree(session->username);
1838         kfree(session->username_in);
1839         kfree(session->targetname);
1840         kfree(session->netdev);
1841         kfree(session->hwaddress);
1842         kfree(session->initiatorname);
1843
1844         iscsi_free_session(cls_session);
1845         scsi_host_put(shost);
1846         module_put(owner);
1847 }
1848 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1849
1850 /**
1851  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1852  * @cls_session: iscsi_cls_session
1853  * @conn_idx: cid
1854  **/
1855 struct iscsi_cls_conn *
1856 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1857 {
1858         struct iscsi_session *session = class_to_transport_session(cls_session);
1859         struct iscsi_conn *conn;
1860         struct iscsi_cls_conn *cls_conn;
1861         char *data;
1862
1863         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1864         if (!cls_conn)
1865                 return NULL;
1866         conn = cls_conn->dd_data;
1867         memset(conn, 0, sizeof(*conn));
1868
1869         conn->session = session;
1870         conn->cls_conn = cls_conn;
1871         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1872         conn->id = conn_idx;
1873         conn->exp_statsn = 0;
1874         conn->tmf_state = TMF_INITIAL;
1875
1876         init_timer(&conn->transport_timer);
1877         conn->transport_timer.data = (unsigned long)conn;
1878         conn->transport_timer.function = iscsi_check_transport_timeouts;
1879
1880         INIT_LIST_HEAD(&conn->run_list);
1881         INIT_LIST_HEAD(&conn->mgmt_run_list);
1882         INIT_LIST_HEAD(&conn->mgmtqueue);
1883         INIT_LIST_HEAD(&conn->xmitqueue);
1884         INIT_LIST_HEAD(&conn->requeue);
1885         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1886
1887         /* allocate login_mtask used for the login/text sequences */
1888         spin_lock_bh(&session->lock);
1889         if (!__kfifo_get(session->mgmtpool.queue,
1890                          (void*)&conn->login_mtask,
1891                          sizeof(void*))) {
1892                 spin_unlock_bh(&session->lock);
1893                 goto login_mtask_alloc_fail;
1894         }
1895         spin_unlock_bh(&session->lock);
1896
1897         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1898         if (!data)
1899                 goto login_mtask_data_alloc_fail;
1900         conn->login_mtask->data = conn->data = data;
1901
1902         init_timer(&conn->tmf_timer);
1903         init_waitqueue_head(&conn->ehwait);
1904
1905         return cls_conn;
1906
1907 login_mtask_data_alloc_fail:
1908         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1909                     sizeof(void*));
1910 login_mtask_alloc_fail:
1911         iscsi_destroy_conn(cls_conn);
1912         return NULL;
1913 }
1914 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1915
1916 /**
1917  * iscsi_conn_teardown - teardown iscsi connection
1918  * cls_conn: iscsi class connection
1919  *
1920  * TODO: we may need to make this into a two step process
1921  * like scsi-mls remove + put host
1922  */
1923 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1924 {
1925         struct iscsi_conn *conn = cls_conn->dd_data;
1926         struct iscsi_session *session = conn->session;
1927         unsigned long flags;
1928
1929         del_timer_sync(&conn->transport_timer);
1930
1931         spin_lock_bh(&session->lock);
1932         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1933         if (session->leadconn == conn) {
1934                 /*
1935                  * leading connection? then give up on recovery.
1936                  */
1937                 session->state = ISCSI_STATE_TERMINATE;
1938                 wake_up(&conn->ehwait);
1939         }
1940         spin_unlock_bh(&session->lock);
1941
1942         /*
1943          * Block until all in-progress commands for this connection
1944          * time out or fail.
1945          */
1946         for (;;) {
1947                 spin_lock_irqsave(session->host->host_lock, flags);
1948                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1949                         spin_unlock_irqrestore(session->host->host_lock, flags);
1950                         break;
1951                 }
1952                 spin_unlock_irqrestore(session->host->host_lock, flags);
1953                 msleep_interruptible(500);
1954                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
1955                                   "host_busy %d host_failed %d\n",
1956                                   session->host->host_busy,
1957                                   session->host->host_failed);
1958                 /*
1959                  * force eh_abort() to unblock
1960                  */
1961                 wake_up(&conn->ehwait);
1962         }
1963
1964         /* flush queued up work because we free the connection below */
1965         iscsi_suspend_tx(conn);
1966
1967         spin_lock_bh(&session->lock);
1968         kfree(conn->data);
1969         kfree(conn->persistent_address);
1970         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1971                     sizeof(void*));
1972         if (session->leadconn == conn)
1973                 session->leadconn = NULL;
1974         spin_unlock_bh(&session->lock);
1975
1976         iscsi_destroy_conn(cls_conn);
1977 }
1978 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1979
1980 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1981 {
1982         struct iscsi_conn *conn = cls_conn->dd_data;
1983         struct iscsi_session *session = conn->session;
1984
1985         if (!session) {
1986                 iscsi_conn_printk(KERN_ERR, conn,
1987                                   "can't start unbound connection\n");
1988                 return -EPERM;
1989         }
1990
1991         if ((session->imm_data_en || !session->initial_r2t_en) &&
1992              session->first_burst > session->max_burst) {
1993                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
1994                                   "first_burst %d max_burst %d\n",
1995                                   session->first_burst, session->max_burst);
1996                 return -EINVAL;
1997         }
1998
1999         if (conn->ping_timeout && !conn->recv_timeout) {
2000                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2001                                   "zero. Using 5 seconds\n.");
2002                 conn->recv_timeout = 5;
2003         }
2004
2005         if (conn->recv_timeout && !conn->ping_timeout) {
2006                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2007                                   "zero. Using 5 seconds.\n");
2008                 conn->ping_timeout = 5;
2009         }
2010
2011         spin_lock_bh(&session->lock);
2012         conn->c_stage = ISCSI_CONN_STARTED;
2013         session->state = ISCSI_STATE_LOGGED_IN;
2014         session->queued_cmdsn = session->cmdsn;
2015
2016         conn->last_recv = jiffies;
2017         conn->last_ping = jiffies;
2018         if (conn->recv_timeout && conn->ping_timeout)
2019                 mod_timer(&conn->transport_timer,
2020                           jiffies + (conn->recv_timeout * HZ));
2021
2022         switch(conn->stop_stage) {
2023         case STOP_CONN_RECOVER:
2024                 /*
2025                  * unblock eh_abort() if it is blocked. re-try all
2026                  * commands after successful recovery
2027                  */
2028                 conn->stop_stage = 0;
2029                 conn->tmf_state = TMF_INITIAL;
2030                 session->age++;
2031                 if (session->age == 16)
2032                         session->age = 0;
2033                 break;
2034         case STOP_CONN_TERM:
2035                 conn->stop_stage = 0;
2036                 break;
2037         default:
2038                 break;
2039         }
2040         spin_unlock_bh(&session->lock);
2041
2042         iscsi_unblock_session(session_to_cls(session));
2043         wake_up(&conn->ehwait);
2044         return 0;
2045 }
2046 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2047
2048 static void
2049 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2050 {
2051         struct iscsi_mgmt_task *mtask, *tmp;
2052
2053         /* handle pending */
2054         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2055                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2056                 iscsi_free_mgmt_task(conn, mtask);
2057         }
2058
2059         /* handle running */
2060         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2061                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2062                 iscsi_free_mgmt_task(conn, mtask);
2063         }
2064
2065         conn->mtask = NULL;
2066 }
2067
2068 static void iscsi_start_session_recovery(struct iscsi_session *session,
2069                                          struct iscsi_conn *conn, int flag)
2070 {
2071         int old_stop_stage;
2072
2073         del_timer_sync(&conn->transport_timer);
2074
2075         mutex_lock(&session->eh_mutex);
2076         spin_lock_bh(&session->lock);
2077         if (conn->stop_stage == STOP_CONN_TERM) {
2078                 spin_unlock_bh(&session->lock);
2079                 mutex_unlock(&session->eh_mutex);
2080                 return;
2081         }
2082
2083         /*
2084          * The LLD either freed/unset the lock on us, or userspace called
2085          * stop but did not create a proper connection (connection was never
2086          * bound or it was unbound then stop was called).
2087          */
2088         if (!conn->recv_lock) {
2089                 spin_unlock_bh(&session->lock);
2090                 mutex_unlock(&session->eh_mutex);
2091                 return;
2092         }
2093
2094         /*
2095          * When this is called for the in_login state, we only want to clean
2096          * up the login task and connection. We do not need to block and set
2097          * the recovery state again
2098          */
2099         if (flag == STOP_CONN_TERM)
2100                 session->state = ISCSI_STATE_TERMINATE;
2101         else if (conn->stop_stage != STOP_CONN_RECOVER)
2102                 session->state = ISCSI_STATE_IN_RECOVERY;
2103
2104         old_stop_stage = conn->stop_stage;
2105         conn->stop_stage = flag;
2106         conn->c_stage = ISCSI_CONN_STOPPED;
2107         spin_unlock_bh(&session->lock);
2108
2109         iscsi_suspend_tx(conn);
2110
2111         write_lock_bh(conn->recv_lock);
2112         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2113         write_unlock_bh(conn->recv_lock);
2114
2115         /*
2116          * for connection level recovery we should not calculate
2117          * header digest. conn->hdr_size used for optimization
2118          * in hdr_extract() and will be re-negotiated at
2119          * set_param() time.
2120          */
2121         if (flag == STOP_CONN_RECOVER) {
2122                 conn->hdrdgst_en = 0;
2123                 conn->datadgst_en = 0;
2124                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2125                     old_stop_stage != STOP_CONN_RECOVER) {
2126                         debug_scsi("blocking session\n");
2127                         iscsi_block_session(session_to_cls(session));
2128                 }
2129         }
2130
2131         /*
2132          * flush queues.
2133          */
2134         spin_lock_bh(&session->lock);
2135         fail_all_commands(conn, -1,
2136                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2137         flush_control_queues(session, conn);
2138         spin_unlock_bh(&session->lock);
2139         mutex_unlock(&session->eh_mutex);
2140 }
2141
2142 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2143 {
2144         struct iscsi_conn *conn = cls_conn->dd_data;
2145         struct iscsi_session *session = conn->session;
2146
2147         switch (flag) {
2148         case STOP_CONN_RECOVER:
2149         case STOP_CONN_TERM:
2150                 iscsi_start_session_recovery(session, conn, flag);
2151                 break;
2152         default:
2153                 iscsi_conn_printk(KERN_ERR, conn,
2154                                   "invalid stop flag %d\n", flag);
2155         }
2156 }
2157 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2158
2159 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2160                     struct iscsi_cls_conn *cls_conn, int is_leading)
2161 {
2162         struct iscsi_session *session = class_to_transport_session(cls_session);
2163         struct iscsi_conn *conn = cls_conn->dd_data;
2164
2165         spin_lock_bh(&session->lock);
2166         if (is_leading)
2167                 session->leadconn = conn;
2168         spin_unlock_bh(&session->lock);
2169
2170         /*
2171          * Unblock xmitworker(), Login Phase will pass through.
2172          */
2173         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2174         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2175         return 0;
2176 }
2177 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2178
2179
2180 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2181                     enum iscsi_param param, char *buf, int buflen)
2182 {
2183         struct iscsi_conn *conn = cls_conn->dd_data;
2184         struct iscsi_session *session = conn->session;
2185         uint32_t value;
2186
2187         switch(param) {
2188         case ISCSI_PARAM_FAST_ABORT:
2189                 sscanf(buf, "%d", &session->fast_abort);
2190                 break;
2191         case ISCSI_PARAM_ABORT_TMO:
2192                 sscanf(buf, "%d", &session->abort_timeout);
2193                 break;
2194         case ISCSI_PARAM_LU_RESET_TMO:
2195                 sscanf(buf, "%d", &session->lu_reset_timeout);
2196                 break;
2197         case ISCSI_PARAM_PING_TMO:
2198                 sscanf(buf, "%d", &conn->ping_timeout);
2199                 break;
2200         case ISCSI_PARAM_RECV_TMO:
2201                 sscanf(buf, "%d", &conn->recv_timeout);
2202                 break;
2203         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2204                 sscanf(buf, "%d", &conn->max_recv_dlength);
2205                 break;
2206         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2207                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2208                 break;
2209         case ISCSI_PARAM_HDRDGST_EN:
2210                 sscanf(buf, "%d", &conn->hdrdgst_en);
2211                 break;
2212         case ISCSI_PARAM_DATADGST_EN:
2213                 sscanf(buf, "%d", &conn->datadgst_en);
2214                 break;
2215         case ISCSI_PARAM_INITIAL_R2T_EN:
2216                 sscanf(buf, "%d", &session->initial_r2t_en);
2217                 break;
2218         case ISCSI_PARAM_MAX_R2T:
2219                 sscanf(buf, "%d", &session->max_r2t);
2220                 break;
2221         case ISCSI_PARAM_IMM_DATA_EN:
2222                 sscanf(buf, "%d", &session->imm_data_en);
2223                 break;
2224         case ISCSI_PARAM_FIRST_BURST:
2225                 sscanf(buf, "%d", &session->first_burst);
2226                 break;
2227         case ISCSI_PARAM_MAX_BURST:
2228                 sscanf(buf, "%d", &session->max_burst);
2229                 break;
2230         case ISCSI_PARAM_PDU_INORDER_EN:
2231                 sscanf(buf, "%d", &session->pdu_inorder_en);
2232                 break;
2233         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2234                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2235                 break;
2236         case ISCSI_PARAM_ERL:
2237                 sscanf(buf, "%d", &session->erl);
2238                 break;
2239         case ISCSI_PARAM_IFMARKER_EN:
2240                 sscanf(buf, "%d", &value);
2241                 BUG_ON(value);
2242                 break;
2243         case ISCSI_PARAM_OFMARKER_EN:
2244                 sscanf(buf, "%d", &value);
2245                 BUG_ON(value);
2246                 break;
2247         case ISCSI_PARAM_EXP_STATSN:
2248                 sscanf(buf, "%u", &conn->exp_statsn);
2249                 break;
2250         case ISCSI_PARAM_USERNAME:
2251                 kfree(session->username);
2252                 session->username = kstrdup(buf, GFP_KERNEL);
2253                 if (!session->username)
2254                         return -ENOMEM;
2255                 break;
2256         case ISCSI_PARAM_USERNAME_IN:
2257                 kfree(session->username_in);
2258                 session->username_in = kstrdup(buf, GFP_KERNEL);
2259                 if (!session->username_in)
2260                         return -ENOMEM;
2261                 break;
2262         case ISCSI_PARAM_PASSWORD:
2263                 kfree(session->password);
2264                 session->password = kstrdup(buf, GFP_KERNEL);
2265                 if (!session->password)
2266                         return -ENOMEM;
2267                 break;
2268         case ISCSI_PARAM_PASSWORD_IN:
2269                 kfree(session->password_in);
2270                 session->password_in = kstrdup(buf, GFP_KERNEL);
2271                 if (!session->password_in)
2272                         return -ENOMEM;
2273                 break;
2274         case ISCSI_PARAM_TARGET_NAME:
2275                 /* this should not change between logins */
2276                 if (session->targetname)
2277                         break;
2278
2279                 session->targetname = kstrdup(buf, GFP_KERNEL);
2280                 if (!session->targetname)
2281                         return -ENOMEM;
2282                 break;
2283         case ISCSI_PARAM_TPGT:
2284                 sscanf(buf, "%d", &session->tpgt);
2285                 break;
2286         case ISCSI_PARAM_PERSISTENT_PORT:
2287                 sscanf(buf, "%d", &conn->persistent_port);
2288                 break;
2289         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2290                 /*
2291                  * this is the address returned in discovery so it should
2292                  * not change between logins.
2293                  */
2294                 if (conn->persistent_address)
2295                         break;
2296
2297                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2298                 if (!conn->persistent_address)
2299                         return -ENOMEM;
2300                 break;
2301         default:
2302                 return -ENOSYS;
2303         }
2304
2305         return 0;
2306 }
2307 EXPORT_SYMBOL_GPL(iscsi_set_param);
2308
2309 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2310                             enum iscsi_param param, char *buf)
2311 {
2312         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2313         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2314         int len;
2315
2316         switch(param) {
2317         case ISCSI_PARAM_FAST_ABORT:
2318                 len = sprintf(buf, "%d\n", session->fast_abort);
2319                 break;
2320         case ISCSI_PARAM_ABORT_TMO:
2321                 len = sprintf(buf, "%d\n", session->abort_timeout);
2322                 break;
2323         case ISCSI_PARAM_LU_RESET_TMO:
2324                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2325                 break;
2326         case ISCSI_PARAM_INITIAL_R2T_EN:
2327                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2328                 break;
2329         case ISCSI_PARAM_MAX_R2T:
2330                 len = sprintf(buf, "%hu\n", session->max_r2t);
2331                 break;
2332         case ISCSI_PARAM_IMM_DATA_EN:
2333                 len = sprintf(buf, "%d\n", session->imm_data_en);
2334                 break;
2335         case ISCSI_PARAM_FIRST_BURST:
2336                 len = sprintf(buf, "%u\n", session->first_burst);
2337                 break;
2338         case ISCSI_PARAM_MAX_BURST:
2339                 len = sprintf(buf, "%u\n", session->max_burst);
2340                 break;
2341         case ISCSI_PARAM_PDU_INORDER_EN:
2342                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2343                 break;
2344         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2345                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2346                 break;
2347         case ISCSI_PARAM_ERL:
2348                 len = sprintf(buf, "%d\n", session->erl);
2349                 break;
2350         case ISCSI_PARAM_TARGET_NAME:
2351                 len = sprintf(buf, "%s\n", session->targetname);
2352                 break;
2353         case ISCSI_PARAM_TPGT:
2354                 len = sprintf(buf, "%d\n", session->tpgt);
2355                 break;
2356         case ISCSI_PARAM_USERNAME:
2357                 len = sprintf(buf, "%s\n", session->username);
2358                 break;
2359         case ISCSI_PARAM_USERNAME_IN:
2360                 len = sprintf(buf, "%s\n", session->username_in);
2361                 break;
2362         case ISCSI_PARAM_PASSWORD:
2363                 len = sprintf(buf, "%s\n", session->password);
2364                 break;
2365         case ISCSI_PARAM_PASSWORD_IN:
2366                 len = sprintf(buf, "%s\n", session->password_in);
2367                 break;
2368         default:
2369                 return -ENOSYS;
2370         }
2371
2372         return len;
2373 }
2374 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2375
2376 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2377                          enum iscsi_param param, char *buf)
2378 {
2379         struct iscsi_conn *conn = cls_conn->dd_data;
2380         int len;
2381
2382         switch(param) {
2383         case ISCSI_PARAM_PING_TMO:
2384                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2385                 break;
2386         case ISCSI_PARAM_RECV_TMO:
2387                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2388                 break;
2389         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2390                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2391                 break;
2392         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2393                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2394                 break;
2395         case ISCSI_PARAM_HDRDGST_EN:
2396                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2397                 break;
2398         case ISCSI_PARAM_DATADGST_EN:
2399                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2400                 break;
2401         case ISCSI_PARAM_IFMARKER_EN:
2402                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2403                 break;
2404         case ISCSI_PARAM_OFMARKER_EN:
2405                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2406                 break;
2407         case ISCSI_PARAM_EXP_STATSN:
2408                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2409                 break;
2410         case ISCSI_PARAM_PERSISTENT_PORT:
2411                 len = sprintf(buf, "%d\n", conn->persistent_port);
2412                 break;
2413         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2414                 len = sprintf(buf, "%s\n", conn->persistent_address);
2415                 break;
2416         default:
2417                 return -ENOSYS;
2418         }
2419
2420         return len;
2421 }
2422 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2423
2424 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2425                          char *buf)
2426 {
2427         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2428         int len;
2429
2430         switch (param) {
2431         case ISCSI_HOST_PARAM_NETDEV_NAME:
2432                 if (!session->netdev)
2433                         len = sprintf(buf, "%s\n", "default");
2434                 else
2435                         len = sprintf(buf, "%s\n", session->netdev);
2436                 break;
2437         case ISCSI_HOST_PARAM_HWADDRESS:
2438                 if (!session->hwaddress)
2439                         len = sprintf(buf, "%s\n", "default");
2440                 else
2441                         len = sprintf(buf, "%s\n", session->hwaddress);
2442                 break;
2443         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2444                 if (!session->initiatorname)
2445                         len = sprintf(buf, "%s\n", "unknown");
2446                 else
2447                         len = sprintf(buf, "%s\n", session->initiatorname);
2448                 break;
2449
2450         default:
2451                 return -ENOSYS;
2452         }
2453
2454         return len;
2455 }
2456 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2457
2458 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2459                          char *buf, int buflen)
2460 {
2461         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2462
2463         switch (param) {
2464         case ISCSI_HOST_PARAM_NETDEV_NAME:
2465                 if (!session->netdev)
2466                         session->netdev = kstrdup(buf, GFP_KERNEL);
2467                 break;
2468         case ISCSI_HOST_PARAM_HWADDRESS:
2469                 if (!session->hwaddress)
2470                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2471                 break;
2472         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2473                 if (!session->initiatorname)
2474                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2475                 break;
2476         default:
2477                 return -ENOSYS;
2478         }
2479
2480         return 0;
2481 }
2482 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2483
2484 MODULE_AUTHOR("Mike Christie");
2485 MODULE_DESCRIPTION("iSCSI library functions");
2486 MODULE_LICENSE("GPL");