git.oblomov.eu Git - linux-2.6/blob - 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, conn->id, 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                         printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
 420                                "invalid data buffer size of %d\n", datalen);
 421                         sc->result = DID_BAD_TARGET << 16;
 422                         goto out;
 423                 }
 424
 425                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
 426                 if (datalen < senselen)
 427                         goto invalid_datalen;
 428
 429                 memcpy(sc->sense_buffer, data + 2,
 430                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 431                 debug_scsi("copied %d bytes of sense\n",
 432                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 433         }
 434
 435         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 436                            ISCSI_FLAG_CMD_OVERFLOW)) {
 437                 int res_count = be32_to_cpu(rhdr->residual_count);
 438
 439                 if (res_count > 0 &&
 440                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 441                      res_count <= scsi_bufflen(sc)))
 442                         scsi_set_resid(sc, res_count);
 443                 else
 444                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 445         } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 446                                   ISCSI_FLAG_CMD_BIDI_OVERFLOW))
 447                 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 448
 449 out:
 450         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 451                    (long)sc, sc->result, ctask->itt);
 452         conn->scsirsp_pdus_cnt++;
 453
 454         __iscsi_put_ctask(ctask);
 455 }
 456
 457 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 458 {
 459         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 460
 461         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 462         conn->tmfrsp_pdus_cnt++;
 463
 464         if (conn->tmf_state != TMF_QUEUED)
 465                 return;
 466
 467         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 468                 conn->tmf_state = TMF_SUCCESS;
 469         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 470                 conn->tmf_state = TMF_NOT_FOUND;
 471         else
 472                 conn->tmf_state = TMF_FAILED;
 473         wake_up(&conn->ehwait);
 474 }
 475
 476 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 477 {
 478         struct iscsi_nopout hdr;
 479         struct iscsi_mgmt_task *mtask;
 480
 481         if (!rhdr && conn->ping_mtask)
 482                 return;
 483
 484         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 485         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 486         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 487
 488         if (rhdr) {
 489                 memcpy(hdr.lun, rhdr->lun, 8);
 490                 hdr.ttt = rhdr->ttt;
 491                 hdr.itt = RESERVED_ITT;
 492         } else
 493                 hdr.ttt = RESERVED_ITT;
 494
 495         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 496         if (!mtask) {
 497                 printk(KERN_ERR "Could not send nopout\n");
 498                 return;
 499         }
 500
 501         /* only track our nops */
 502         if (!rhdr) {
 503                 conn->ping_mtask = mtask;
 504                 conn->last_ping = jiffies;
 505         }
 506         scsi_queue_work(conn->session->host, &conn->xmitwork);
 507 }
 508
 509 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 510                                char *data, int datalen)
 511 {
 512         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 513         struct iscsi_hdr rejected_pdu;
 514         uint32_t itt;
 515
 516         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 517
 518         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 519                 if (ntoh24(reject->dlength) > datalen)
 520                         return ISCSI_ERR_PROTO;
 521
 522                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 523                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 524                         itt = get_itt(rejected_pdu.itt);
 525                         printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
 526                                 "due to DataDigest error.\n", itt,
 527                                 rejected_pdu.opcode);
 528                 }
 529         }
 530         return 0;
 531 }
 532
 533 /**
 534  * __iscsi_complete_pdu - complete pdu
 535  * @conn: iscsi conn
 536  * @hdr: iscsi header
 537  * @data: data buffer
 538  * @datalen: len of data buffer
 539  *
 540  * Completes pdu processing by freeing any resources allocated at
 541  * queuecommand or send generic. session lock must be held and verify
 542  * itt must have been called.
 543  */
 544 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 545                                 char *data, int datalen)
 546 {
 547         struct iscsi_session *session = conn->session;
 548         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 549         struct iscsi_cmd_task *ctask;
 550         struct iscsi_mgmt_task *mtask;
 551         uint32_t itt;
 552
 553         conn->last_recv = jiffies;
 554         if (hdr->itt != RESERVED_ITT)
 555                 itt = get_itt(hdr->itt);
 556         else
 557                 itt = ~0U;
 558
 559         if (itt < session->cmds_max) {
 560                 ctask = session->cmds[itt];
 561
 562                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 563                            opcode, conn->id, ctask->itt, datalen);
 564
 565                 switch(opcode) {
 566                 case ISCSI_OP_SCSI_CMD_RSP:
 567                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 568                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 569                                            datalen);
 570                         break;
 571                 case ISCSI_OP_SCSI_DATA_IN:
 572                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 573                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 574                                 conn->scsirsp_pdus_cnt++;
 575                                 __iscsi_put_ctask(ctask);
 576                         }
 577                         break;
 578                 case ISCSI_OP_R2T:
 579                         /* LLD handles this for now */
 580                         break;
 581                 default:
 582                         rc = ISCSI_ERR_BAD_OPCODE;
 583                         break;
 584                 }
 585         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 586                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 587                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 588
 589                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 590                            opcode, conn->id, mtask->itt, datalen);
 591
 592                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 593                 switch(opcode) {
 594                 case ISCSI_OP_LOGOUT_RSP:
 595                         if (datalen) {
 596                                 rc = ISCSI_ERR_PROTO;
 597                                 break;
 598                         }
 599                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 600                         /* fall through */
 601                 case ISCSI_OP_LOGIN_RSP:
 602                 case ISCSI_OP_TEXT_RSP:
 603                         /*
 604                          * login related PDU's exp_statsn is handled in
 605                          * userspace
 606                          */
 607                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 608                                 rc = ISCSI_ERR_CONN_FAILED;
 609                         iscsi_free_mgmt_task(conn, mtask);
 610                         break;
 611                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 612                         if (datalen) {
 613                                 rc = ISCSI_ERR_PROTO;
 614                                 break;
 615                         }
 616
 617                         iscsi_tmf_rsp(conn, hdr);
 618                         iscsi_free_mgmt_task(conn, mtask);
 619                         break;
 620                 case ISCSI_OP_NOOP_IN:
 621                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 622                             datalen) {
 623                                 rc = ISCSI_ERR_PROTO;
 624                                 break;
 625                         }
 626                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 627
 628                         if (conn->ping_mtask != mtask) {
 629                                 /*
 630                                  * If this is not in response to one of our
 631                                  * nops then it must be from userspace.
 632                                  */
 633                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 634                                                    datalen))
 635                                         rc = ISCSI_ERR_CONN_FAILED;
 636                         }
 637                         iscsi_free_mgmt_task(conn, mtask);
 638                         break;
 639                 default:
 640                         rc = ISCSI_ERR_BAD_OPCODE;
 641                         break;
 642                 }
 643         } else if (itt == ~0U) {
 644                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 645
 646                 switch(opcode) {
 647                 case ISCSI_OP_NOOP_IN:
 648                         if (datalen) {
 649                                 rc = ISCSI_ERR_PROTO;
 650                                 break;
 651                         }
 652
 653                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 654                                 break;
 655
 656                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 657                         break;
 658                 case ISCSI_OP_REJECT:
 659                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 660                         break;
 661                 case ISCSI_OP_ASYNC_EVENT:
 662                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 663                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 664                                 rc = ISCSI_ERR_CONN_FAILED;
 665                         break;
 666                 default:
 667                         rc = ISCSI_ERR_BAD_OPCODE;
 668                         break;
 669                 }
 670         } else
 671                 rc = ISCSI_ERR_BAD_ITT;
 672
 673         return rc;
 674 }
 675
 676 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 677                        char *data, int datalen)
 678 {
 679         int rc;
 680
 681         spin_lock(&conn->session->lock);
 682         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 683         spin_unlock(&conn->session->lock);
 684         return rc;
 685 }
 686 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 687
 688 /* verify itt (itt encoding: age+cid+itt) */
 689 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 690                      uint32_t *ret_itt)
 691 {
 692         struct iscsi_session *session = conn->session;
 693         struct iscsi_cmd_task *ctask;
 694         uint32_t itt;
 695
 696         if (hdr->itt != RESERVED_ITT) {
 697                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
 698                     (session->age << ISCSI_AGE_SHIFT)) {
 699                         printk(KERN_ERR "iscsi: received itt %x expected "
 700                                 "session age (%x)\n", (__force u32)hdr->itt,
 701                                 session->age & ISCSI_AGE_MASK);
 702                         return ISCSI_ERR_BAD_ITT;
 703                 }
 704
 705                 if (((__force u32)hdr->itt & ISCSI_CID_MASK) !=
 706                     (conn->id << ISCSI_CID_SHIFT)) {
 707                         printk(KERN_ERR "iscsi: received itt %x, expected "
 708                                 "CID (%x)\n", (__force u32)hdr->itt, conn->id);
 709                         return ISCSI_ERR_BAD_ITT;
 710                 }
 711                 itt = get_itt(hdr->itt);
 712         } else
 713                 itt = ~0U;
 714
 715         if (itt < session->cmds_max) {
 716                 ctask = session->cmds[itt];
 717
 718                 if (!ctask->sc) {
 719                         printk(KERN_INFO "iscsi: dropping ctask with "
 720                                "itt 0x%x\n", ctask->itt);
 721                         /* force drop */
 722                         return ISCSI_ERR_NO_SCSI_CMD;
 723                 }
 724
 725                 if (ctask->sc->SCp.phase != session->age) {
 726                         printk(KERN_ERR "iscsi: ctask's session age %d, "
 727                                 "expected %d\n", ctask->sc->SCp.phase,
 728                                 session->age);
 729                         return ISCSI_ERR_SESSION_FAILED;
 730                 }
 731         }
 732
 733         *ret_itt = itt;
 734         return 0;
 735 }
 736 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 737
 738 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 739 {
 740         struct iscsi_session *session = conn->session;
 741         unsigned long flags;
 742
 743         spin_lock_irqsave(&session->lock, flags);
 744         if (session->state == ISCSI_STATE_FAILED) {
 745                 spin_unlock_irqrestore(&session->lock, flags);
 746                 return;
 747         }
 748
 749         if (conn->stop_stage == 0)
 750                 session->state = ISCSI_STATE_FAILED;
 751         spin_unlock_irqrestore(&session->lock, flags);
 752         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 753         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 754         iscsi_conn_error(conn->cls_conn, err);
 755 }
 756 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 757
 758 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 759                              struct iscsi_mgmt_task *mtask)
 760 {
 761         struct iscsi_session *session = conn->session;
 762         struct iscsi_hdr *hdr = mtask->hdr;
 763         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 764
 765         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 766             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 767                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 768         /*
 769          * pre-format CmdSN for outgoing PDU.
 770          */
 771         nop->cmdsn = cpu_to_be32(session->cmdsn);
 772         if (hdr->itt != RESERVED_ITT) {
 773                 hdr->itt = build_itt(mtask->itt, conn->id, session->age);
 774                 /*
 775                  * TODO: We always use immediate, so we never hit this.
 776                  * If we start to send tmfs or nops as non-immediate then
 777                  * we should start checking the cmdsn numbers for mgmt tasks.
 778                  */
 779                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 780                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 781                         session->queued_cmdsn++;
 782                         session->cmdsn++;
 783                 }
 784         }
 785
 786         if (session->tt->init_mgmt_task)
 787                 session->tt->init_mgmt_task(conn, mtask);
 788
 789         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 790                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 791                    mtask->data_count);
 792 }
 793
 794 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 795 {
 796         struct iscsi_hdr *hdr = conn->mtask->hdr;
 797         int rc;
 798
 799         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 800                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 801         spin_unlock_bh(&conn->session->lock);
 802
 803         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 804         spin_lock_bh(&conn->session->lock);
 805         if (rc)
 806                 return rc;
 807
 808         /* done with this in-progress mtask */
 809         conn->mtask = NULL;
 810         return 0;
 811 }
 812
 813 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 814 {
 815         struct iscsi_session *session = conn->session;
 816
 817         /*
 818          * Check for iSCSI window and take care of CmdSN wrap-around
 819          */
 820         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 821                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 822                            "CmdSN %u/%u\n", session->exp_cmdsn,
 823                            session->max_cmdsn, session->cmdsn,
 824                            session->queued_cmdsn);
 825                 return -ENOSPC;
 826         }
 827         return 0;
 828 }
 829
 830 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 831 {
 832         struct iscsi_cmd_task *ctask = conn->ctask;
 833         int rc;
 834
 835         __iscsi_get_ctask(ctask);
 836         spin_unlock_bh(&conn->session->lock);
 837         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 838         spin_lock_bh(&conn->session->lock);
 839         __iscsi_put_ctask(ctask);
 840         if (!rc)
 841                 /* done with this ctask */
 842                 conn->ctask = NULL;
 843         return rc;
 844 }
 845
 846 /**
 847  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 848  * @ctask: ctask to requeue
 849  *
 850  * LLDs that need to run a ctask from the session workqueue should call
 851  * this. The session lock must be held.
 852  */
 853 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 854 {
 855         struct iscsi_conn *conn = ctask->conn;
 856
 857         list_move_tail(&ctask->running, &conn->requeue);
 858         scsi_queue_work(conn->session->host, &conn->xmitwork);
 859 }
 860 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 861
 862 /**
 863  * iscsi_data_xmit - xmit any command into the scheduled connection
 864  * @conn: iscsi connection
 865  *
 866  * Notes:
 867  *      The function can return -EAGAIN in which case the caller must
 868  *      re-schedule it again later or recover. '0' return code means
 869  *      successful xmit.
 870  **/
 871 static int iscsi_data_xmit(struct iscsi_conn *conn)
 872 {
 873         int rc = 0;
 874
 875         spin_lock_bh(&conn->session->lock);
 876         if (unlikely(conn->suspend_tx)) {
 877                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 878                 spin_unlock_bh(&conn->session->lock);
 879                 return -ENODATA;
 880         }
 881
 882         if (conn->ctask) {
 883                 rc = iscsi_xmit_ctask(conn);
 884                 if (rc)
 885                         goto again;
 886         }
 887
 888         if (conn->mtask) {
 889                 rc = iscsi_xmit_mtask(conn);
 890                 if (rc)
 891                         goto again;
 892         }
 893
 894         /*
 895          * process mgmt pdus like nops before commands since we should
 896          * only have one nop-out as a ping from us and targets should not
 897          * overflow us with nop-ins
 898          */
 899 check_mgmt:
 900         while (!list_empty(&conn->mgmtqueue)) {
 901                 conn->mtask = list_entry(conn->mgmtqueue.next,
 902                                          struct iscsi_mgmt_task, running);
 903                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 904                         iscsi_free_mgmt_task(conn, conn->mtask);
 905                         conn->mtask = NULL;
 906                         continue;
 907                 }
 908
 909                 iscsi_prep_mtask(conn, conn->mtask);
 910                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
 911                 rc = iscsi_xmit_mtask(conn);
 912                 if (rc)
 913                         goto again;
 914         }
 915
 916         /* process pending command queue */
 917         while (!list_empty(&conn->xmitqueue)) {
 918                 if (conn->tmf_state == TMF_QUEUED)
 919                         break;
 920
 921                 conn->ctask = list_entry(conn->xmitqueue.next,
 922                                          struct iscsi_cmd_task, running);
 923                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 924                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
 925                         continue;
 926                 }
 927                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
 928                         fail_command(conn, conn->ctask, DID_ABORT << 16);
 929                         continue;
 930                 }
 931
 932                 conn->ctask->state = ISCSI_TASK_RUNNING;
 933                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
 934                 rc = iscsi_xmit_ctask(conn);
 935                 if (rc)
 936                         goto again;
 937                 /*
 938                  * we could continuously get new ctask requests so
 939                  * we need to check the mgmt queue for nops that need to
 940                  * be sent to aviod starvation
 941                  */
 942                 if (!list_empty(&conn->mgmtqueue))
 943                         goto check_mgmt;
 944         }
 945
 946         while (!list_empty(&conn->requeue)) {
 947                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
 948                         break;
 949
 950                 /*
 951                  * we always do fastlogout - conn stop code will clean up.
 952                  */
 953                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 954                         break;
 955
 956                 conn->ctask = list_entry(conn->requeue.next,
 957                                          struct iscsi_cmd_task, running);
 958                 conn->ctask->state = ISCSI_TASK_RUNNING;
 959                 list_move_tail(conn->requeue.next, &conn->run_list);
 960                 rc = iscsi_xmit_ctask(conn);
 961                 if (rc)
 962                         goto again;
 963                 if (!list_empty(&conn->mgmtqueue))
 964                         goto check_mgmt;
 965         }
 966         spin_unlock_bh(&conn->session->lock);
 967         return -ENODATA;
 968
 969 again:
 970         if (unlikely(conn->suspend_tx))
 971                 rc = -ENODATA;
 972         spin_unlock_bh(&conn->session->lock);
 973         return rc;
 974 }
 975
 976 static void iscsi_xmitworker(struct work_struct *work)
 977 {
 978         struct iscsi_conn *conn =
 979                 container_of(work, struct iscsi_conn, xmitwork);
 980         int rc;
 981         /*
 982          * serialize Xmit worker on a per-connection basis.
 983          */
 984         do {
 985                 rc = iscsi_data_xmit(conn);
 986         } while (rc >= 0 || rc == -EAGAIN);
 987 }
 988
 989 enum {
 990         FAILURE_BAD_HOST = 1,
 991         FAILURE_SESSION_FAILED,
 992         FAILURE_SESSION_FREED,
 993         FAILURE_WINDOW_CLOSED,
 994         FAILURE_OOM,
 995         FAILURE_SESSION_TERMINATE,
 996         FAILURE_SESSION_IN_RECOVERY,
 997         FAILURE_SESSION_RECOVERY_TIMEOUT,
 998         FAILURE_SESSION_LOGGING_OUT,
 999 };
1000
1001 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1002 {
1003         struct Scsi_Host *host;
1004         int reason = 0;
1005         struct iscsi_session *session;
1006         struct iscsi_conn *conn;
1007         struct iscsi_cmd_task *ctask = NULL;
1008
1009         sc->scsi_done = done;
1010         sc->result = 0;
1011         sc->SCp.ptr = NULL;
1012
1013         host = sc->device->host;
1014         spin_unlock(host->host_lock);
1015
1016         session = iscsi_hostdata(host->hostdata);
1017         spin_lock(&session->lock);
1018
1019         /*
1020          * ISCSI_STATE_FAILED is a temp. state. The recovery
1021          * code will decide what is best to do with command queued
1022          * during this time
1023          */
1024         if (session->state != ISCSI_STATE_LOGGED_IN &&
1025             session->state != ISCSI_STATE_FAILED) {
1026                 /*
1027                  * to handle the race between when we set the recovery state
1028                  * and block the session we requeue here (commands could
1029                  * be entering our queuecommand while a block is starting
1030                  * up because the block code is not locked)
1031                  */
1032                 switch (session->state) {
1033                 case ISCSI_STATE_IN_RECOVERY:
1034                         reason = FAILURE_SESSION_IN_RECOVERY;
1035                         goto reject;
1036                 case ISCSI_STATE_LOGGING_OUT:
1037                         reason = FAILURE_SESSION_LOGGING_OUT;
1038                         goto reject;
1039                 case ISCSI_STATE_RECOVERY_FAILED:
1040                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1041                         break;
1042                 case ISCSI_STATE_TERMINATE:
1043                         reason = FAILURE_SESSION_TERMINATE;
1044                         break;
1045                 default:
1046                         reason = FAILURE_SESSION_FREED;
1047                 }
1048                 goto fault;
1049         }
1050
1051         conn = session->leadconn;
1052         if (!conn) {
1053                 reason = FAILURE_SESSION_FREED;
1054                 goto fault;
1055         }
1056
1057         if (iscsi_check_cmdsn_window_closed(conn)) {
1058                 reason = FAILURE_WINDOW_CLOSED;
1059                 goto reject;
1060         }
1061
1062         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1063                          sizeof(void*))) {
1064                 reason = FAILURE_OOM;
1065                 goto reject;
1066         }
1067         session->queued_cmdsn++;
1068
1069         sc->SCp.phase = session->age;
1070         sc->SCp.ptr = (char *)ctask;
1071
1072         atomic_set(&ctask->refcount, 1);
1073         ctask->state = ISCSI_TASK_PENDING;
1074         ctask->conn = conn;
1075         ctask->sc = sc;
1076         INIT_LIST_HEAD(&ctask->running);
1077
1078         list_add_tail(&ctask->running, &conn->xmitqueue);
1079         spin_unlock(&session->lock);
1080
1081         scsi_queue_work(host, &conn->xmitwork);
1082         spin_lock(host->host_lock);
1083         return 0;
1084
1085 reject:
1086         spin_unlock(&session->lock);
1087         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1088         spin_lock(host->host_lock);
1089         return SCSI_MLQUEUE_HOST_BUSY;
1090
1091 fault:
1092         spin_unlock(&session->lock);
1093         printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
1094                sc->cmnd[0], reason);
1095         sc->result = (DID_NO_CONNECT << 16);
1096         scsi_set_resid(sc, scsi_bufflen(sc));
1097         sc->scsi_done(sc);
1098         spin_lock(host->host_lock);
1099         return 0;
1100 }
1101 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1102
1103 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1104 {
1105         if (depth > ISCSI_MAX_CMD_PER_LUN)
1106                 depth = ISCSI_MAX_CMD_PER_LUN;
1107         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1108         return sdev->queue_depth;
1109 }
1110 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1111
1112 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1113 {
1114         struct iscsi_session *session = class_to_transport_session(cls_session);
1115
1116         spin_lock_bh(&session->lock);
1117         if (session->state != ISCSI_STATE_LOGGED_IN) {
1118                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1119                 if (session->leadconn)
1120                         wake_up(&session->leadconn->ehwait);
1121         }
1122         spin_unlock_bh(&session->lock);
1123 }
1124 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1125
1126 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1127 {
1128         struct Scsi_Host *host = sc->device->host;
1129         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1130         struct iscsi_conn *conn = session->leadconn;
1131
1132         mutex_lock(&session->eh_mutex);
1133         spin_lock_bh(&session->lock);
1134         if (session->state == ISCSI_STATE_TERMINATE) {
1135 failed:
1136                 debug_scsi("failing host reset: session terminated "
1137                            "[CID %d age %d]\n", conn->id, session->age);
1138                 spin_unlock_bh(&session->lock);
1139                 mutex_unlock(&session->eh_mutex);
1140                 return FAILED;
1141         }
1142
1143         spin_unlock_bh(&session->lock);
1144         mutex_unlock(&session->eh_mutex);
1145         /*
1146          * we drop the lock here but the leadconn cannot be destoyed while
1147          * we are in the scsi eh
1148          */
1149         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1150
1151         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1152         wait_event_interruptible(conn->ehwait,
1153                                  session->state == ISCSI_STATE_TERMINATE ||
1154                                  session->state == ISCSI_STATE_LOGGED_IN ||
1155                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1156         if (signal_pending(current))
1157                 flush_signals(current);
1158
1159         mutex_lock(&session->eh_mutex);
1160         spin_lock_bh(&session->lock);
1161         if (session->state == ISCSI_STATE_LOGGED_IN)
1162                 printk(KERN_INFO "iscsi: host reset succeeded\n");
1163         else
1164                 goto failed;
1165         spin_unlock_bh(&session->lock);
1166         mutex_unlock(&session->eh_mutex);
1167         return SUCCESS;
1168 }
1169 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1170
1171 static void iscsi_tmf_timedout(unsigned long data)
1172 {
1173         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1174         struct iscsi_session *session = conn->session;
1175
1176         spin_lock(&session->lock);
1177         if (conn->tmf_state == TMF_QUEUED) {
1178                 conn->tmf_state = TMF_TIMEDOUT;
1179                 debug_scsi("tmf timedout\n");
1180                 /* unblock eh_abort() */
1181                 wake_up(&conn->ehwait);
1182         }
1183         spin_unlock(&session->lock);
1184 }
1185
1186 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1187                                    struct iscsi_tm *hdr, int age,
1188                                    int timeout)
1189 {
1190         struct iscsi_session *session = conn->session;
1191         struct iscsi_mgmt_task *mtask;
1192
1193         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1194                                       NULL, 0);
1195         if (!mtask) {
1196                 spin_unlock_bh(&session->lock);
1197                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1198                 spin_lock_bh(&session->lock);
1199                 debug_scsi("tmf exec failure\n");
1200                 return -EPERM;
1201         }
1202         conn->tmfcmd_pdus_cnt++;
1203         conn->tmf_timer.expires = timeout * HZ + jiffies;
1204         conn->tmf_timer.function = iscsi_tmf_timedout;
1205         conn->tmf_timer.data = (unsigned long)conn;
1206         add_timer(&conn->tmf_timer);
1207         debug_scsi("tmf set timeout\n");
1208
1209         spin_unlock_bh(&session->lock);
1210         mutex_unlock(&session->eh_mutex);
1211         scsi_queue_work(session->host, &conn->xmitwork);
1212
1213         /*
1214          * block eh thread until:
1215          *
1216          * 1) tmf response
1217          * 2) tmf timeout
1218          * 3) session is terminated or restarted or userspace has
1219          * given up on recovery
1220          */
1221         wait_event_interruptible(conn->ehwait, age != session->age ||
1222                                  session->state != ISCSI_STATE_LOGGED_IN ||
1223                                  conn->tmf_state != TMF_QUEUED);
1224         if (signal_pending(current))
1225                 flush_signals(current);
1226         del_timer_sync(&conn->tmf_timer);
1227
1228         mutex_lock(&session->eh_mutex);
1229         spin_lock_bh(&session->lock);
1230         /* if the session drops it will clean up the mtask */
1231         if (age != session->age ||
1232             session->state != ISCSI_STATE_LOGGED_IN)
1233                 return -ENOTCONN;
1234         return 0;
1235 }
1236
1237 /*
1238  * Fail commands. session lock held and recv side suspended and xmit
1239  * thread flushed
1240  */
1241 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun)
1242 {
1243         struct iscsi_cmd_task *ctask, *tmp;
1244
1245         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1246                 conn->ctask = NULL;
1247
1248         /* flush pending */
1249         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1250                 if (lun == ctask->sc->device->lun || lun == -1) {
1251                         debug_scsi("failing pending sc %p itt 0x%x\n",
1252                                    ctask->sc, ctask->itt);
1253                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1254                 }
1255         }
1256
1257         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1258                 if (lun == ctask->sc->device->lun || lun == -1) {
1259                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1260                                    ctask->sc, ctask->itt);
1261                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1262                 }
1263         }
1264
1265         /* fail all other running */
1266         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1267                 if (lun == ctask->sc->device->lun || lun == -1) {
1268                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1269                                    ctask->sc, ctask->itt);
1270                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1271                 }
1272         }
1273 }
1274
1275 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1276 {
1277         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1278         scsi_flush_work(conn->session->host);
1279 }
1280
1281 static void iscsi_start_tx(struct iscsi_conn *conn)
1282 {
1283         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1284         scsi_queue_work(conn->session->host, &conn->xmitwork);
1285 }
1286
1287 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1288 {
1289         struct iscsi_cls_session *cls_session;
1290         struct iscsi_session *session;
1291         struct iscsi_conn *conn;
1292         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1293
1294         cls_session = starget_to_session(scsi_target(scmd->device));
1295         session = class_to_transport_session(cls_session);
1296
1297         debug_scsi("scsi cmd %p timedout\n", scmd);
1298
1299         spin_lock(&session->lock);
1300         if (session->state != ISCSI_STATE_LOGGED_IN) {
1301                 /*
1302                  * We are probably in the middle of iscsi recovery so let
1303                  * that complete and handle the error.
1304                  */
1305                 rc = EH_RESET_TIMER;
1306                 goto done;
1307         }
1308
1309         conn = session->leadconn;
1310         if (!conn) {
1311                 /* In the middle of shuting down */
1312                 rc = EH_RESET_TIMER;
1313                 goto done;
1314         }
1315
1316         if (!conn->recv_timeout && !conn->ping_timeout)
1317                 goto done;
1318         /*
1319          * if the ping timedout then we are in the middle of cleaning up
1320          * and can let the iscsi eh handle it
1321          */
1322         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1323                             (conn->ping_timeout * HZ), jiffies))
1324                 rc = EH_RESET_TIMER;
1325         /*
1326          * if we are about to check the transport then give the command
1327          * more time
1328          */
1329         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1330                            jiffies))
1331                 rc = EH_RESET_TIMER;
1332         /* if in the middle of checking the transport then give us more time */
1333         if (conn->ping_mtask)
1334                 rc = EH_RESET_TIMER;
1335 done:
1336         spin_unlock(&session->lock);
1337         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1338         return rc;
1339 }
1340
1341 static void iscsi_check_transport_timeouts(unsigned long data)
1342 {
1343         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1344         struct iscsi_session *session = conn->session;
1345         unsigned long timeout, next_timeout = 0, last_recv;
1346
1347         spin_lock(&session->lock);
1348         if (session->state != ISCSI_STATE_LOGGED_IN)
1349                 goto done;
1350
1351         timeout = conn->recv_timeout;
1352         if (!timeout)
1353                 goto done;
1354
1355         timeout *= HZ;
1356         last_recv = conn->last_recv;
1357         if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
1358                            jiffies)) {
1359                 printk(KERN_ERR "ping timeout of %d secs expired, "
1360                        "last rx %lu, last ping %lu, now %lu\n",
1361                        conn->ping_timeout, last_recv,
1362                        conn->last_ping, jiffies);
1363                 spin_unlock(&session->lock);
1364                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1365                 return;
1366         }
1367
1368         if (time_before_eq(last_recv + timeout, jiffies)) {
1369                 if (time_before_eq(conn->last_ping, last_recv)) {
1370                         /* send a ping to try to provoke some traffic */
1371                         debug_scsi("Sending nopout as ping on conn %p\n", conn);
1372                         iscsi_send_nopout(conn, NULL);
1373                 }
1374                 next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
1375         } else {
1376                 next_timeout = last_recv + timeout;
1377         }
1378
1379         if (next_timeout) {
1380                 debug_scsi("Setting next tmo %lu\n", next_timeout);
1381                 mod_timer(&conn->transport_timer, next_timeout);
1382         }
1383 done:
1384         spin_unlock(&session->lock);
1385 }
1386
1387 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1388                                       struct iscsi_tm *hdr)
1389 {
1390         memset(hdr, 0, sizeof(*hdr));
1391         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1392         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1393         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1394         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1395         hdr->rtt = ctask->hdr->itt;
1396         hdr->refcmdsn = ctask->hdr->cmdsn;
1397 }
1398
1399 int iscsi_eh_abort(struct scsi_cmnd *sc)
1400 {
1401         struct Scsi_Host *host = sc->device->host;
1402         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1403         struct iscsi_conn *conn;
1404         struct iscsi_cmd_task *ctask;
1405         struct iscsi_tm *hdr;
1406         int rc, age;
1407
1408         mutex_lock(&session->eh_mutex);
1409         spin_lock_bh(&session->lock);
1410         /*
1411          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1412          * got the command.
1413          */
1414         if (!sc->SCp.ptr) {
1415                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1416                 spin_unlock_bh(&session->lock);
1417                 mutex_unlock(&session->eh_mutex);
1418                 return SUCCESS;
1419         }
1420
1421         /*
1422          * If we are not logged in or we have started a new session
1423          * then let the host reset code handle this
1424          */
1425         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1426             sc->SCp.phase != session->age) {
1427                 spin_unlock_bh(&session->lock);
1428                 mutex_unlock(&session->eh_mutex);
1429                 return FAILED;
1430         }
1431
1432         conn = session->leadconn;
1433         conn->eh_abort_cnt++;
1434         age = session->age;
1435
1436         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1437         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1438
1439         /* ctask completed before time out */
1440         if (!ctask->sc) {
1441                 debug_scsi("sc completed while abort in progress\n");
1442                 goto success;
1443         }
1444
1445         if (ctask->state == ISCSI_TASK_PENDING) {
1446                 fail_command(conn, ctask, DID_ABORT << 16);
1447                 goto success;
1448         }
1449
1450         /* only have one tmf outstanding at a time */
1451         if (conn->tmf_state != TMF_INITIAL)
1452                 goto failed;
1453         conn->tmf_state = TMF_QUEUED;
1454
1455         hdr = &conn->tmhdr;
1456         iscsi_prep_abort_task_pdu(ctask, hdr);
1457
1458         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1459                 rc = FAILED;
1460                 goto failed;
1461         }
1462
1463         switch (conn->tmf_state) {
1464         case TMF_SUCCESS:
1465                 spin_unlock_bh(&session->lock);
1466                 iscsi_suspend_tx(conn);
1467                 /*
1468                  * clean up task if aborted. grab the recv lock as a writer
1469                  */
1470                 write_lock_bh(conn->recv_lock);
1471                 spin_lock(&session->lock);
1472                 fail_command(conn, ctask, DID_ABORT << 16);
1473                 conn->tmf_state = TMF_INITIAL;
1474                 spin_unlock(&session->lock);
1475                 write_unlock_bh(conn->recv_lock);
1476                 iscsi_start_tx(conn);
1477                 goto success_unlocked;
1478         case TMF_TIMEDOUT:
1479                 spin_unlock_bh(&session->lock);
1480                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1481                 goto failed_unlocked;
1482         case TMF_NOT_FOUND:
1483                 if (!sc->SCp.ptr) {
1484                         conn->tmf_state = TMF_INITIAL;
1485                         /* ctask completed before tmf abort response */
1486                         debug_scsi("sc completed while abort in progress\n");
1487                         goto success;
1488                 }
1489                 /* fall through */
1490         default:
1491                 conn->tmf_state = TMF_INITIAL;
1492                 goto failed;
1493         }
1494
1495 success:
1496         spin_unlock_bh(&session->lock);
1497 success_unlocked:
1498         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1499         mutex_unlock(&session->eh_mutex);
1500         return SUCCESS;
1501
1502 failed:
1503         spin_unlock_bh(&session->lock);
1504 failed_unlocked:
1505         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1506                     ctask ? ctask->itt : 0);
1507         mutex_unlock(&session->eh_mutex);
1508         return FAILED;
1509 }
1510 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1511
1512 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1513 {
1514         memset(hdr, 0, sizeof(*hdr));
1515         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1516         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1517         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1518         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1519         hdr->rtt = RESERVED_ITT;
1520 }
1521
1522 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1523 {
1524         struct Scsi_Host *host = sc->device->host;
1525         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1526         struct iscsi_conn *conn;
1527         struct iscsi_tm *hdr;
1528         int rc = FAILED;
1529
1530         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1531
1532         mutex_lock(&session->eh_mutex);
1533         spin_lock_bh(&session->lock);
1534         /*
1535          * Just check if we are not logged in. We cannot check for
1536          * the phase because the reset could come from a ioctl.
1537          */
1538         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1539                 goto unlock;
1540         conn = session->leadconn;
1541
1542         /* only have one tmf outstanding at a time */
1543         if (conn->tmf_state != TMF_INITIAL)
1544                 goto unlock;
1545         conn->tmf_state = TMF_QUEUED;
1546
1547         hdr = &conn->tmhdr;
1548         iscsi_prep_lun_reset_pdu(sc, hdr);
1549
1550         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1551                                     session->lu_reset_timeout)) {
1552                 rc = FAILED;
1553                 goto unlock;
1554         }
1555
1556         switch (conn->tmf_state) {
1557         case TMF_SUCCESS:
1558                 break;
1559         case TMF_TIMEDOUT:
1560                 spin_unlock_bh(&session->lock);
1561                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1562                 goto done;
1563         default:
1564                 conn->tmf_state = TMF_INITIAL;
1565                 goto unlock;
1566         }
1567
1568         rc = SUCCESS;
1569         spin_unlock_bh(&session->lock);
1570
1571         iscsi_suspend_tx(conn);
1572         /* need to grab the recv lock then session lock */
1573         write_lock_bh(conn->recv_lock);
1574         spin_lock(&session->lock);
1575         fail_all_commands(conn, sc->device->lun);
1576         conn->tmf_state = TMF_INITIAL;
1577         spin_unlock(&session->lock);
1578         write_unlock_bh(conn->recv_lock);
1579
1580         iscsi_start_tx(conn);
1581         goto done;
1582
1583 unlock:
1584         spin_unlock_bh(&session->lock);
1585 done:
1586         debug_scsi("iscsi_eh_device_reset %s\n",
1587                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1588         mutex_unlock(&session->eh_mutex);
1589         return rc;
1590 }
1591 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1592
1593 /*
1594  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1595  * should be accessed via kfifo_{get,put} on q->queue.
1596  * Optionally, the caller can obtain the array of object pointers
1597  * by passing in a non-NULL @items pointer
1598  */
1599 int
1600 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1601 {
1602         int i, num_arrays = 1;
1603
1604         memset(q, 0, sizeof(*q));
1605
1606         q->max = max;
1607
1608         /* If the user passed an items pointer, he wants a copy of
1609          * the array. */
1610         if (items)
1611                 num_arrays++;
1612         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1613         if (q->pool == NULL)
1614                 goto enomem;
1615
1616         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1617                               GFP_KERNEL, NULL);
1618         if (q->queue == ERR_PTR(-ENOMEM))
1619                 goto enomem;
1620
1621         for (i = 0; i < max; i++) {
1622                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1623                 if (q->pool[i] == NULL) {
1624                         q->max = i;
1625                         goto enomem;
1626                 }
1627                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1628         }
1629
1630         if (items) {
1631                 *items = q->pool + max;
1632                 memcpy(*items, q->pool, max * sizeof(void *));
1633         }
1634
1635         return 0;
1636
1637 enomem:
1638         iscsi_pool_free(q);
1639         return -ENOMEM;
1640 }
1641 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1642
1643 void iscsi_pool_free(struct iscsi_pool *q)
1644 {
1645         int i;
1646
1647         for (i = 0; i < q->max; i++)
1648                 kfree(q->pool[i]);
1649         if (q->pool)
1650                 kfree(q->pool);
1651 }
1652 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1653
1654 /*
1655  * iSCSI Session's hostdata organization:
1656  *
1657  *    *------------------* <== hostdata_session(host->hostdata)
1658  *    | ptr to class sess|
1659  *    |------------------| <== iscsi_hostdata(host->hostdata)
1660  *    | iscsi_session    |
1661  *    *------------------*
1662  */
1663
1664 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1665                                  _sz % sizeof(unsigned long))
1666
1667 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1668
1669 /**
1670  * iscsi_session_setup - create iscsi cls session and host and session
1671  * @scsit: scsi transport template
1672  * @iscsit: iscsi transport template
1673  * @cmds_max: scsi host can queue
1674  * @qdepth: scsi host cmds per lun
1675  * @cmd_task_size: LLD ctask private data size
1676  * @mgmt_task_size: LLD mtask private data size
1677  * @initial_cmdsn: initial CmdSN
1678  * @hostno: host no allocated
1679  *
1680  * This can be used by software iscsi_transports that allocate
1681  * a session per scsi host.
1682  **/
1683 struct iscsi_cls_session *
1684 iscsi_session_setup(struct iscsi_transport *iscsit,
1685                     struct scsi_transport_template *scsit,
1686                     uint16_t cmds_max, uint16_t qdepth,
1687                     int cmd_task_size, int mgmt_task_size,
1688                     uint32_t initial_cmdsn, uint32_t *hostno)
1689 {
1690         struct Scsi_Host *shost;
1691         struct iscsi_session *session;
1692         struct iscsi_cls_session *cls_session;
1693         int cmd_i;
1694
1695         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1696                 if (qdepth != 0)
1697                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1698                               "Queue depth must be between 1 and %d.\n",
1699                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1700                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1701         }
1702
1703         if (!is_power_of_2(cmds_max) ||
1704             cmds_max >= ISCSI_MGMT_ITT_OFFSET) {
1705                 if (cmds_max != 0)
1706                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1707                                "can_queue must be a power of 2 and between "
1708                                "2 and %d - setting to %d.\n", cmds_max,
1709                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1710                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1711         }
1712
1713         shost = scsi_host_alloc(iscsit->host_template,
1714                                 hostdata_privsize(sizeof(*session)));
1715         if (!shost)
1716                 return NULL;
1717
1718         /* the iscsi layer takes one task for reserve */
1719         shost->can_queue = cmds_max - 1;
1720         shost->cmd_per_lun = qdepth;
1721         shost->max_id = 1;
1722         shost->max_channel = 0;
1723         shost->max_lun = iscsit->max_lun;
1724         shost->max_cmd_len = iscsit->max_cmd_len;
1725         shost->transportt = scsit;
1726         shost->transportt->create_work_queue = 1;
1727         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1728         *hostno = shost->host_no;
1729
1730         session = iscsi_hostdata(shost->hostdata);
1731         memset(session, 0, sizeof(struct iscsi_session));
1732         session->host = shost;
1733         session->state = ISCSI_STATE_FREE;
1734         session->fast_abort = 1;
1735         session->lu_reset_timeout = 15;
1736         session->abort_timeout = 10;
1737         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1738         session->cmds_max = cmds_max;
1739         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1740         session->exp_cmdsn = initial_cmdsn + 1;
1741         session->max_cmdsn = initial_cmdsn + 1;
1742         session->max_r2t = 1;
1743         session->tt = iscsit;
1744         mutex_init(&session->eh_mutex);
1745
1746         /* initialize SCSI PDU commands pool */
1747         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1748                             (void***)&session->cmds,
1749                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1750                 goto cmdpool_alloc_fail;
1751
1752         /* pre-format cmds pool with ITT */
1753         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1754                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1755
1756                 if (cmd_task_size)
1757                         ctask->dd_data = &ctask[1];
1758                 ctask->itt = cmd_i;
1759                 INIT_LIST_HEAD(&ctask->running);
1760         }
1761
1762         spin_lock_init(&session->lock);
1763
1764         /* initialize immediate command pool */
1765         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1766                            (void***)&session->mgmt_cmds,
1767                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1768                 goto mgmtpool_alloc_fail;
1769
1770
1771         /* pre-format immediate cmds pool with ITT */
1772         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1773                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1774
1775                 if (mgmt_task_size)
1776                         mtask->dd_data = &mtask[1];
1777                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1778                 INIT_LIST_HEAD(&mtask->running);
1779         }
1780
1781         if (scsi_add_host(shost, NULL))
1782                 goto add_host_fail;
1783
1784         if (!try_module_get(iscsit->owner))
1785                 goto cls_session_fail;
1786
1787         cls_session = iscsi_create_session(shost, iscsit, 0);
1788         if (!cls_session)
1789                 goto module_put;
1790         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1791
1792         return cls_session;
1793
1794 module_put:
1795         module_put(iscsit->owner);
1796 cls_session_fail:
1797         scsi_remove_host(shost);
1798 add_host_fail:
1799         iscsi_pool_free(&session->mgmtpool);
1800 mgmtpool_alloc_fail:
1801         iscsi_pool_free(&session->cmdpool);
1802 cmdpool_alloc_fail:
1803         scsi_host_put(shost);
1804         return NULL;
1805 }
1806 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1807
1808 /**
1809  * iscsi_session_teardown - destroy session, host, and cls_session
1810  * shost: scsi host
1811  *
1812  * This can be used by software iscsi_transports that allocate
1813  * a session per scsi host.
1814  **/
1815 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1816 {
1817         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1818         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1819         struct module *owner = cls_session->transport->owner;
1820
1821         iscsi_remove_session(cls_session);
1822         scsi_remove_host(shost);
1823
1824         iscsi_pool_free(&session->mgmtpool);
1825         iscsi_pool_free(&session->cmdpool);
1826
1827         kfree(session->password);
1828         kfree(session->password_in);
1829         kfree(session->username);
1830         kfree(session->username_in);
1831         kfree(session->targetname);
1832         kfree(session->netdev);
1833         kfree(session->hwaddress);
1834         kfree(session->initiatorname);
1835
1836         iscsi_free_session(cls_session);
1837         scsi_host_put(shost);
1838         module_put(owner);
1839 }
1840 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1841
1842 /**
1843  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1844  * @cls_session: iscsi_cls_session
1845  * @conn_idx: cid
1846  **/
1847 struct iscsi_cls_conn *
1848 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1849 {
1850         struct iscsi_session *session = class_to_transport_session(cls_session);
1851         struct iscsi_conn *conn;
1852         struct iscsi_cls_conn *cls_conn;
1853         char *data;
1854
1855         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1856         if (!cls_conn)
1857                 return NULL;
1858         conn = cls_conn->dd_data;
1859         memset(conn, 0, sizeof(*conn));
1860
1861         conn->session = session;
1862         conn->cls_conn = cls_conn;
1863         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1864         conn->id = conn_idx;
1865         conn->exp_statsn = 0;
1866         conn->tmf_state = TMF_INITIAL;
1867
1868         init_timer(&conn->transport_timer);
1869         conn->transport_timer.data = (unsigned long)conn;
1870         conn->transport_timer.function = iscsi_check_transport_timeouts;
1871
1872         INIT_LIST_HEAD(&conn->run_list);
1873         INIT_LIST_HEAD(&conn->mgmt_run_list);
1874         INIT_LIST_HEAD(&conn->mgmtqueue);
1875         INIT_LIST_HEAD(&conn->xmitqueue);
1876         INIT_LIST_HEAD(&conn->requeue);
1877         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1878
1879         /* allocate login_mtask used for the login/text sequences */
1880         spin_lock_bh(&session->lock);
1881         if (!__kfifo_get(session->mgmtpool.queue,
1882                          (void*)&conn->login_mtask,
1883                          sizeof(void*))) {
1884                 spin_unlock_bh(&session->lock);
1885                 goto login_mtask_alloc_fail;
1886         }
1887         spin_unlock_bh(&session->lock);
1888
1889         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1890         if (!data)
1891                 goto login_mtask_data_alloc_fail;
1892         conn->login_mtask->data = conn->data = data;
1893
1894         init_timer(&conn->tmf_timer);
1895         init_waitqueue_head(&conn->ehwait);
1896
1897         return cls_conn;
1898
1899 login_mtask_data_alloc_fail:
1900         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1901                     sizeof(void*));
1902 login_mtask_alloc_fail:
1903         iscsi_destroy_conn(cls_conn);
1904         return NULL;
1905 }
1906 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1907
1908 /**
1909  * iscsi_conn_teardown - teardown iscsi connection
1910  * cls_conn: iscsi class connection
1911  *
1912  * TODO: we may need to make this into a two step process
1913  * like scsi-mls remove + put host
1914  */
1915 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1916 {
1917         struct iscsi_conn *conn = cls_conn->dd_data;
1918         struct iscsi_session *session = conn->session;
1919         unsigned long flags;
1920
1921         del_timer_sync(&conn->transport_timer);
1922
1923         spin_lock_bh(&session->lock);
1924         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1925         if (session->leadconn == conn) {
1926                 /*
1927                  * leading connection? then give up on recovery.
1928                  */
1929                 session->state = ISCSI_STATE_TERMINATE;
1930                 wake_up(&conn->ehwait);
1931         }
1932         spin_unlock_bh(&session->lock);
1933
1934         /*
1935          * Block until all in-progress commands for this connection
1936          * time out or fail.
1937          */
1938         for (;;) {
1939                 spin_lock_irqsave(session->host->host_lock, flags);
1940                 if (!session->host->host_busy) { /* OK for ERL == 0 */
1941                         spin_unlock_irqrestore(session->host->host_lock, flags);
1942                         break;
1943                 }
1944                 spin_unlock_irqrestore(session->host->host_lock, flags);
1945                 msleep_interruptible(500);
1946                 printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
1947                        "host_failed %d\n", session->host->host_busy,
1948                        session->host->host_failed);
1949                 /*
1950                  * force eh_abort() to unblock
1951                  */
1952                 wake_up(&conn->ehwait);
1953         }
1954
1955         /* flush queued up work because we free the connection below */
1956         iscsi_suspend_tx(conn);
1957
1958         spin_lock_bh(&session->lock);
1959         kfree(conn->data);
1960         kfree(conn->persistent_address);
1961         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1962                     sizeof(void*));
1963         if (session->leadconn == conn)
1964                 session->leadconn = NULL;
1965         spin_unlock_bh(&session->lock);
1966
1967         iscsi_destroy_conn(cls_conn);
1968 }
1969 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1970
1971 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1972 {
1973         struct iscsi_conn *conn = cls_conn->dd_data;
1974         struct iscsi_session *session = conn->session;
1975
1976         if (!session) {
1977                 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1978                 return -EPERM;
1979         }
1980
1981         if ((session->imm_data_en || !session->initial_r2t_en) &&
1982              session->first_burst > session->max_burst) {
1983                 printk("iscsi: invalid burst lengths: "
1984                        "first_burst %d max_burst %d\n",
1985                        session->first_burst, session->max_burst);
1986                 return -EINVAL;
1987         }
1988
1989         if (conn->ping_timeout && !conn->recv_timeout) {
1990                 printk(KERN_ERR "iscsi: invalid recv timeout of zero "
1991                       "Using 5 seconds\n.");
1992                 conn->recv_timeout = 5;
1993         }
1994
1995         if (conn->recv_timeout && !conn->ping_timeout) {
1996                 printk(KERN_ERR "iscsi: invalid ping timeout of zero "
1997                       "Using 5 seconds.\n");
1998                 conn->ping_timeout = 5;
1999         }
2000
2001         spin_lock_bh(&session->lock);
2002         conn->c_stage = ISCSI_CONN_STARTED;
2003         session->state = ISCSI_STATE_LOGGED_IN;
2004         session->queued_cmdsn = session->cmdsn;
2005
2006         conn->last_recv = jiffies;
2007         conn->last_ping = jiffies;
2008         if (conn->recv_timeout && conn->ping_timeout)
2009                 mod_timer(&conn->transport_timer,
2010                           jiffies + (conn->recv_timeout * HZ));
2011
2012         switch(conn->stop_stage) {
2013         case STOP_CONN_RECOVER:
2014                 /*
2015                  * unblock eh_abort() if it is blocked. re-try all
2016                  * commands after successful recovery
2017                  */
2018                 conn->stop_stage = 0;
2019                 conn->tmf_state = TMF_INITIAL;
2020                 session->age++;
2021                 spin_unlock_bh(&session->lock);
2022
2023                 iscsi_unblock_session(session_to_cls(session));
2024                 wake_up(&conn->ehwait);
2025                 return 0;
2026         case STOP_CONN_TERM:
2027                 conn->stop_stage = 0;
2028                 break;
2029         default:
2030                 break;
2031         }
2032         spin_unlock_bh(&session->lock);
2033
2034         return 0;
2035 }
2036 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2037
2038 static void
2039 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2040 {
2041         struct iscsi_mgmt_task *mtask, *tmp;
2042
2043         /* handle pending */
2044         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2045                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2046                 iscsi_free_mgmt_task(conn, mtask);
2047         }
2048
2049         /* handle running */
2050         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2051                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2052                 iscsi_free_mgmt_task(conn, mtask);
2053         }
2054
2055         conn->mtask = NULL;
2056 }
2057
2058 static void iscsi_start_session_recovery(struct iscsi_session *session,
2059                                          struct iscsi_conn *conn, int flag)
2060 {
2061         int old_stop_stage;
2062
2063         del_timer_sync(&conn->transport_timer);
2064
2065         mutex_lock(&session->eh_mutex);
2066         spin_lock_bh(&session->lock);
2067         if (conn->stop_stage == STOP_CONN_TERM) {
2068                 spin_unlock_bh(&session->lock);
2069                 mutex_unlock(&session->eh_mutex);
2070                 return;
2071         }
2072
2073         /*
2074          * The LLD either freed/unset the lock on us, or userspace called
2075          * stop but did not create a proper connection (connection was never
2076          * bound or it was unbound then stop was called).
2077          */
2078         if (!conn->recv_lock) {
2079                 spin_unlock_bh(&session->lock);
2080                 mutex_unlock(&session->eh_mutex);
2081                 return;
2082         }
2083
2084         /*
2085          * When this is called for the in_login state, we only want to clean
2086          * up the login task and connection. We do not need to block and set
2087          * the recovery state again
2088          */
2089         if (flag == STOP_CONN_TERM)
2090                 session->state = ISCSI_STATE_TERMINATE;
2091         else if (conn->stop_stage != STOP_CONN_RECOVER)
2092                 session->state = ISCSI_STATE_IN_RECOVERY;
2093
2094         old_stop_stage = conn->stop_stage;
2095         conn->stop_stage = flag;
2096         conn->c_stage = ISCSI_CONN_STOPPED;
2097         spin_unlock_bh(&session->lock);
2098
2099         iscsi_suspend_tx(conn);
2100
2101         write_lock_bh(conn->recv_lock);
2102         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2103         write_unlock_bh(conn->recv_lock);
2104
2105         /*
2106          * for connection level recovery we should not calculate
2107          * header digest. conn->hdr_size used for optimization
2108          * in hdr_extract() and will be re-negotiated at
2109          * set_param() time.
2110          */
2111         if (flag == STOP_CONN_RECOVER) {
2112                 conn->hdrdgst_en = 0;
2113                 conn->datadgst_en = 0;
2114                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2115                     old_stop_stage != STOP_CONN_RECOVER) {
2116                         debug_scsi("blocking session\n");
2117                         iscsi_block_session(session_to_cls(session));
2118                 }
2119         }
2120
2121         /*
2122          * flush queues.
2123          */
2124         spin_lock_bh(&session->lock);
2125         fail_all_commands(conn, -1);
2126         flush_control_queues(session, conn);
2127         spin_unlock_bh(&session->lock);
2128         mutex_unlock(&session->eh_mutex);
2129 }
2130
2131 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2132 {
2133         struct iscsi_conn *conn = cls_conn->dd_data;
2134         struct iscsi_session *session = conn->session;
2135
2136         switch (flag) {
2137         case STOP_CONN_RECOVER:
2138         case STOP_CONN_TERM:
2139                 iscsi_start_session_recovery(session, conn, flag);
2140                 break;
2141         default:
2142                 printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
2143         }
2144 }
2145 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2146
2147 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2148                     struct iscsi_cls_conn *cls_conn, int is_leading)
2149 {
2150         struct iscsi_session *session = class_to_transport_session(cls_session);
2151         struct iscsi_conn *conn = cls_conn->dd_data;
2152
2153         spin_lock_bh(&session->lock);
2154         if (is_leading)
2155                 session->leadconn = conn;
2156         spin_unlock_bh(&session->lock);
2157
2158         /*
2159          * Unblock xmitworker(), Login Phase will pass through.
2160          */
2161         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2162         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2163         return 0;
2164 }
2165 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2166
2167
2168 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2169                     enum iscsi_param param, char *buf, int buflen)
2170 {
2171         struct iscsi_conn *conn = cls_conn->dd_data;
2172         struct iscsi_session *session = conn->session;
2173         uint32_t value;
2174
2175         switch(param) {
2176         case ISCSI_PARAM_FAST_ABORT:
2177                 sscanf(buf, "%d", &session->fast_abort);
2178                 break;
2179         case ISCSI_PARAM_ABORT_TMO:
2180                 sscanf(buf, "%d", &session->abort_timeout);
2181                 break;
2182         case ISCSI_PARAM_LU_RESET_TMO:
2183                 sscanf(buf, "%d", &session->lu_reset_timeout);
2184                 break;
2185         case ISCSI_PARAM_PING_TMO:
2186                 sscanf(buf, "%d", &conn->ping_timeout);
2187                 break;
2188         case ISCSI_PARAM_RECV_TMO:
2189                 sscanf(buf, "%d", &conn->recv_timeout);
2190                 break;
2191         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2192                 sscanf(buf, "%d", &conn->max_recv_dlength);
2193                 break;
2194         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2195                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2196                 break;
2197         case ISCSI_PARAM_HDRDGST_EN:
2198                 sscanf(buf, "%d", &conn->hdrdgst_en);
2199                 break;
2200         case ISCSI_PARAM_DATADGST_EN:
2201                 sscanf(buf, "%d", &conn->datadgst_en);
2202                 break;
2203         case ISCSI_PARAM_INITIAL_R2T_EN:
2204                 sscanf(buf, "%d", &session->initial_r2t_en);
2205                 break;
2206         case ISCSI_PARAM_MAX_R2T:
2207                 sscanf(buf, "%d", &session->max_r2t);
2208                 break;
2209         case ISCSI_PARAM_IMM_DATA_EN:
2210                 sscanf(buf, "%d", &session->imm_data_en);
2211                 break;
2212         case ISCSI_PARAM_FIRST_BURST:
2213                 sscanf(buf, "%d", &session->first_burst);
2214                 break;
2215         case ISCSI_PARAM_MAX_BURST:
2216                 sscanf(buf, "%d", &session->max_burst);
2217                 break;
2218         case ISCSI_PARAM_PDU_INORDER_EN:
2219                 sscanf(buf, "%d", &session->pdu_inorder_en);
2220                 break;
2221         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2222                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2223                 break;
2224         case ISCSI_PARAM_ERL:
2225                 sscanf(buf, "%d", &session->erl);
2226                 break;
2227         case ISCSI_PARAM_IFMARKER_EN:
2228                 sscanf(buf, "%d", &value);
2229                 BUG_ON(value);
2230                 break;
2231         case ISCSI_PARAM_OFMARKER_EN:
2232                 sscanf(buf, "%d", &value);
2233                 BUG_ON(value);
2234                 break;
2235         case ISCSI_PARAM_EXP_STATSN:
2236                 sscanf(buf, "%u", &conn->exp_statsn);
2237                 break;
2238         case ISCSI_PARAM_USERNAME:
2239                 kfree(session->username);
2240                 session->username = kstrdup(buf, GFP_KERNEL);
2241                 if (!session->username)
2242                         return -ENOMEM;
2243                 break;
2244         case ISCSI_PARAM_USERNAME_IN:
2245                 kfree(session->username_in);
2246                 session->username_in = kstrdup(buf, GFP_KERNEL);
2247                 if (!session->username_in)
2248                         return -ENOMEM;
2249                 break;
2250         case ISCSI_PARAM_PASSWORD:
2251                 kfree(session->password);
2252                 session->password = kstrdup(buf, GFP_KERNEL);
2253                 if (!session->password)
2254                         return -ENOMEM;
2255                 break;
2256         case ISCSI_PARAM_PASSWORD_IN:
2257                 kfree(session->password_in);
2258                 session->password_in = kstrdup(buf, GFP_KERNEL);
2259                 if (!session->password_in)
2260                         return -ENOMEM;
2261                 break;
2262         case ISCSI_PARAM_TARGET_NAME:
2263                 /* this should not change between logins */
2264                 if (session->targetname)
2265                         break;
2266
2267                 session->targetname = kstrdup(buf, GFP_KERNEL);
2268                 if (!session->targetname)
2269                         return -ENOMEM;
2270                 break;
2271         case ISCSI_PARAM_TPGT:
2272                 sscanf(buf, "%d", &session->tpgt);
2273                 break;
2274         case ISCSI_PARAM_PERSISTENT_PORT:
2275                 sscanf(buf, "%d", &conn->persistent_port);
2276                 break;
2277         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2278                 /*
2279                  * this is the address returned in discovery so it should
2280                  * not change between logins.
2281                  */
2282                 if (conn->persistent_address)
2283                         break;
2284
2285                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2286                 if (!conn->persistent_address)
2287                         return -ENOMEM;
2288                 break;
2289         default:
2290                 return -ENOSYS;
2291         }
2292
2293         return 0;
2294 }
2295 EXPORT_SYMBOL_GPL(iscsi_set_param);
2296
2297 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2298                             enum iscsi_param param, char *buf)
2299 {
2300         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2301         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2302         int len;
2303
2304         switch(param) {
2305         case ISCSI_PARAM_FAST_ABORT:
2306                 len = sprintf(buf, "%d\n", session->fast_abort);
2307                 break;
2308         case ISCSI_PARAM_ABORT_TMO:
2309                 len = sprintf(buf, "%d\n", session->abort_timeout);
2310                 break;
2311         case ISCSI_PARAM_LU_RESET_TMO:
2312                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2313                 break;
2314         case ISCSI_PARAM_INITIAL_R2T_EN:
2315                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2316                 break;
2317         case ISCSI_PARAM_MAX_R2T:
2318                 len = sprintf(buf, "%hu\n", session->max_r2t);
2319                 break;
2320         case ISCSI_PARAM_IMM_DATA_EN:
2321                 len = sprintf(buf, "%d\n", session->imm_data_en);
2322                 break;
2323         case ISCSI_PARAM_FIRST_BURST:
2324                 len = sprintf(buf, "%u\n", session->first_burst);
2325                 break;
2326         case ISCSI_PARAM_MAX_BURST:
2327                 len = sprintf(buf, "%u\n", session->max_burst);
2328                 break;
2329         case ISCSI_PARAM_PDU_INORDER_EN:
2330                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2331                 break;
2332         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2333                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2334                 break;
2335         case ISCSI_PARAM_ERL:
2336                 len = sprintf(buf, "%d\n", session->erl);
2337                 break;
2338         case ISCSI_PARAM_TARGET_NAME:
2339                 len = sprintf(buf, "%s\n", session->targetname);
2340                 break;
2341         case ISCSI_PARAM_TPGT:
2342                 len = sprintf(buf, "%d\n", session->tpgt);
2343                 break;
2344         case ISCSI_PARAM_USERNAME:
2345                 len = sprintf(buf, "%s\n", session->username);
2346                 break;
2347         case ISCSI_PARAM_USERNAME_IN:
2348                 len = sprintf(buf, "%s\n", session->username_in);
2349                 break;
2350         case ISCSI_PARAM_PASSWORD:
2351                 len = sprintf(buf, "%s\n", session->password);
2352                 break;
2353         case ISCSI_PARAM_PASSWORD_IN:
2354                 len = sprintf(buf, "%s\n", session->password_in);
2355                 break;
2356         default:
2357                 return -ENOSYS;
2358         }
2359
2360         return len;
2361 }
2362 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2363
2364 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2365                          enum iscsi_param param, char *buf)
2366 {
2367         struct iscsi_conn *conn = cls_conn->dd_data;
2368         int len;
2369
2370         switch(param) {
2371         case ISCSI_PARAM_PING_TMO:
2372                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2373                 break;
2374         case ISCSI_PARAM_RECV_TMO:
2375                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2376                 break;
2377         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2378                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2379                 break;
2380         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2381                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2382                 break;
2383         case ISCSI_PARAM_HDRDGST_EN:
2384                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2385                 break;
2386         case ISCSI_PARAM_DATADGST_EN:
2387                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2388                 break;
2389         case ISCSI_PARAM_IFMARKER_EN:
2390                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2391                 break;
2392         case ISCSI_PARAM_OFMARKER_EN:
2393                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2394                 break;
2395         case ISCSI_PARAM_EXP_STATSN:
2396                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2397                 break;
2398         case ISCSI_PARAM_PERSISTENT_PORT:
2399                 len = sprintf(buf, "%d\n", conn->persistent_port);
2400                 break;
2401         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2402                 len = sprintf(buf, "%s\n", conn->persistent_address);
2403                 break;
2404         default:
2405                 return -ENOSYS;
2406         }
2407
2408         return len;
2409 }
2410 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2411
2412 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2413                          char *buf)
2414 {
2415         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2416         int len;
2417
2418         switch (param) {
2419         case ISCSI_HOST_PARAM_NETDEV_NAME:
2420                 if (!session->netdev)
2421                         len = sprintf(buf, "%s\n", "default");
2422                 else
2423                         len = sprintf(buf, "%s\n", session->netdev);
2424                 break;
2425         case ISCSI_HOST_PARAM_HWADDRESS:
2426                 if (!session->hwaddress)
2427                         len = sprintf(buf, "%s\n", "default");
2428                 else
2429                         len = sprintf(buf, "%s\n", session->hwaddress);
2430                 break;
2431         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2432                 if (!session->initiatorname)
2433                         len = sprintf(buf, "%s\n", "unknown");
2434                 else
2435                         len = sprintf(buf, "%s\n", session->initiatorname);
2436                 break;
2437
2438         default:
2439                 return -ENOSYS;
2440         }
2441
2442         return len;
2443 }
2444 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2445
2446 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2447                          char *buf, int buflen)
2448 {
2449         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2450
2451         switch (param) {
2452         case ISCSI_HOST_PARAM_NETDEV_NAME:
2453                 if (!session->netdev)
2454                         session->netdev = kstrdup(buf, GFP_KERNEL);
2455                 break;
2456         case ISCSI_HOST_PARAM_HWADDRESS:
2457                 if (!session->hwaddress)
2458                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2459                 break;
2460         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2461                 if (!session->initiatorname)
2462                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2463                 break;
2464         default:
2465                 return -ENOSYS;
2466         }
2467
2468         return 0;
2469 }
2470 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2471
2472 MODULE_AUTHOR("Mike Christie");
2473 MODULE_DESCRIPTION("iSCSI library functions");
2474 MODULE_LICENSE("GPL");