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