drivers/scsi/libiscsi.c

   1 /*
   2  * iSCSI lib functions
   3  *
   4  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   5  * Copyright (C) 2004 - 2006 Mike Christie
   6  * Copyright (C) 2004 - 2005 Dmitry Yusupov
   7  * Copyright (C) 2004 - 2005 Alex Aizman
   8  * maintained by open-iscsi@googlegroups.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  */
  24 #include <linux/types.h>
  25 #include <linux/kfifo.h>
  26 #include <linux/delay.h>
  27 #include <linux/log2.h>
  28 #include <asm/unaligned.h>
  29 #include <net/tcp.h>
  30 #include <scsi/scsi_cmnd.h>
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_tcq.h>
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi.h>
  36 #include <scsi/iscsi_proto.h>
  37 #include <scsi/scsi_transport.h>
  38 #include <scsi/scsi_transport_iscsi.h>
  39 #include <scsi/libiscsi.h>
  40
  41 struct iscsi_session *
  42 class_to_transport_session(struct iscsi_cls_session *cls_session)
  43 {
  44         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
  45         return iscsi_hostdata(shost->hostdata);
  46 }
  47 EXPORT_SYMBOL_GPL(class_to_transport_session);
  48
  49 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  50 #define SNA32_CHECK 2147483648UL
  51
  52 static int iscsi_sna_lt(u32 n1, u32 n2)
  53 {
  54         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  55                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  56 }
  57
  58 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  59 static int iscsi_sna_lte(u32 n1, u32 n2)
  60 {
  61         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  62                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  63 }
  64
  65 void
  66 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
  67 {
  68         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
  69         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
  70
  71         /*
  72          * standard specifies this check for when to update expected and
  73          * max sequence numbers
  74          */
  75         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
  76                 return;
  77
  78         if (exp_cmdsn != session->exp_cmdsn &&
  79             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
  80                 session->exp_cmdsn = exp_cmdsn;
  81
  82         if (max_cmdsn != session->max_cmdsn &&
  83             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
  84                 session->max_cmdsn = max_cmdsn;
  85                 /*
  86                  * if the window closed with IO queued, then kick the
  87                  * xmit thread
  88                  */
  89                 if (!list_empty(&session->leadconn->xmitqueue) ||
  90                     !list_empty(&session->leadconn->mgmtqueue))
  91                         scsi_queue_work(session->host,
  92                                         &session->leadconn->xmitwork);
  93         }
  94 }
  95 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
  96
  97 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
  98                                    struct iscsi_data *hdr)
  99 {
 100         struct iscsi_conn *conn = ctask->conn;
 101
 102         memset(hdr, 0, sizeof(struct iscsi_data));
 103         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 104         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
 105         ctask->unsol_datasn++;
 106         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 107         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
 108
 109         hdr->itt = ctask->hdr->itt;
 110         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 111         hdr->offset = cpu_to_be32(ctask->unsol_offset);
 112
 113         if (ctask->unsol_count > conn->max_xmit_dlength) {
 114                 hton24(hdr->dlength, conn->max_xmit_dlength);
 115                 ctask->data_count = conn->max_xmit_dlength;
 116                 ctask->unsol_offset += ctask->data_count;
 117                 hdr->flags = 0;
 118         } else {
 119                 hton24(hdr->dlength, ctask->unsol_count);
 120                 ctask->data_count = ctask->unsol_count;
 121                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
 122         }
 123 }
 124 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
 125
 126 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
 127 {
 128         unsigned exp_len = ctask->hdr_len + len;
 129
 130         if (exp_len > ctask->hdr_max) {
 131                 WARN_ON(1);
 132                 return -EINVAL;
 133         }
 134
 135         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 136         ctask->hdr_len = exp_len;
 137         return 0;
 138 }
 139
 140 /*
 141  * make an extended cdb AHS
 142  */
 143 static int iscsi_prep_ecdb_ahs(struct iscsi_cmd_task *ctask)
 144 {
 145         struct scsi_cmnd *cmd = ctask->sc;
 146         unsigned rlen, pad_len;
 147         unsigned short ahslength;
 148         struct iscsi_ecdb_ahdr *ecdb_ahdr;
 149         int rc;
 150
 151         ecdb_ahdr = iscsi_next_hdr(ctask);
 152         rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
 153
 154         BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
 155         ahslength = rlen + sizeof(ecdb_ahdr->reserved);
 156
 157         pad_len = iscsi_padding(rlen);
 158
 159         rc = iscsi_add_hdr(ctask, sizeof(ecdb_ahdr->ahslength) +
 160                            sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
 161         if (rc)
 162                 return rc;
 163
 164         if (pad_len)
 165                 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
 166
 167         ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
 168         ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
 169         ecdb_ahdr->reserved = 0;
 170         memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
 171
 172         debug_scsi("iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
 173                    "rlen %d pad_len %d ahs_length %d iscsi_headers_size %u\n",
 174                    cmd->cmd_len, rlen, pad_len, ahslength, ctask->hdr_len);
 175
 176         return 0;
 177 }
 178
 179 static int iscsi_prep_bidi_ahs(struct iscsi_cmd_task *ctask)
 180 {
 181         struct scsi_cmnd *sc = ctask->sc;
 182         struct iscsi_rlength_ahdr *rlen_ahdr;
 183         int rc;
 184
 185         rlen_ahdr = iscsi_next_hdr(ctask);
 186         rc = iscsi_add_hdr(ctask, sizeof(*rlen_ahdr));
 187         if (rc)
 188                 return rc;
 189
 190         rlen_ahdr->ahslength =
 191                 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
 192                                                   sizeof(rlen_ahdr->reserved));
 193         rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
 194         rlen_ahdr->reserved = 0;
 195         rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
 196
 197         debug_scsi("bidi-in rlen_ahdr->read_length(%d) "
 198                    "rlen_ahdr->ahslength(%d)\n",
 199                    be32_to_cpu(rlen_ahdr->read_length),
 200                    be16_to_cpu(rlen_ahdr->ahslength));
 201         return 0;
 202 }
 203
 204 /**
 205  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 206  * @ctask: iscsi cmd task
 207  *
 208  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 209  * fields like dlength or final based on how much data it sends
 210  */
 211 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 212 {
 213         struct iscsi_conn *conn = ctask->conn;
 214         struct iscsi_session *session = conn->session;
 215         struct iscsi_cmd *hdr = ctask->hdr;
 216         struct scsi_cmnd *sc = ctask->sc;
 217         unsigned hdrlength, cmd_len;
 218         int rc;
 219
 220         ctask->hdr_len = 0;
 221         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
 222         if (rc)
 223                 return rc;
 224         hdr->opcode = ISCSI_OP_SCSI_CMD;
 225         hdr->flags = ISCSI_ATTR_SIMPLE;
 226         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 227         hdr->itt = build_itt(ctask->itt, session->age);
 228         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 229         session->cmdsn++;
 230         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 231         cmd_len = sc->cmd_len;
 232         if (cmd_len < ISCSI_CDB_SIZE)
 233                 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
 234         else if (cmd_len > ISCSI_CDB_SIZE) {
 235                 rc = iscsi_prep_ecdb_ahs(ctask);
 236                 if (rc)
 237                         return rc;
 238                 cmd_len = ISCSI_CDB_SIZE;
 239         }
 240         memcpy(hdr->cdb, sc->cmnd, cmd_len);
 241
 242         ctask->imm_count = 0;
 243         if (scsi_bidi_cmnd(sc)) {
 244                 hdr->flags |= ISCSI_FLAG_CMD_READ;
 245                 rc = iscsi_prep_bidi_ahs(ctask);
 246                 if (rc)
 247                         return rc;
 248         }
 249         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 250                 unsigned out_len = scsi_out(sc)->length;
 251                 hdr->data_length = cpu_to_be32(out_len);
 252                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 253                 /*
 254                  * Write counters:
 255                  *
 256                  *      imm_count       bytes to be sent right after
 257                  *                      SCSI PDU Header
 258                  *
 259                  *      unsol_count     bytes(as Data-Out) to be sent
 260                  *                      without R2T ack right after
 261                  *                      immediate data
 262                  *
 263                  *      r2t_data_count  bytes to be sent via R2T ack's
 264                  *
 265                  *      pad_count       bytes to be sent as zero-padding
 266                  */
 267                 ctask->unsol_count = 0;
 268                 ctask->unsol_offset = 0;
 269                 ctask->unsol_datasn = 0;
 270
 271                 if (session->imm_data_en) {
 272                         if (out_len >= session->first_burst)
 273                                 ctask->imm_count = min(session->first_burst,
 274                                                         conn->max_xmit_dlength);
 275                         else
 276                                 ctask->imm_count = min(out_len,
 277                                                         conn->max_xmit_dlength);
 278                         hton24(hdr->dlength, ctask->imm_count);
 279                 } else
 280                         zero_data(hdr->dlength);
 281
 282                 if (!session->initial_r2t_en) {
 283                         ctask->unsol_count = min(session->first_burst, out_len)
 284                                                              - ctask->imm_count;
 285                         ctask->unsol_offset = ctask->imm_count;
 286                 }
 287
 288                 if (!ctask->unsol_count)
 289                         /* No unsolicit Data-Out's */
 290                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 291         } else {
 292                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 293                 zero_data(hdr->dlength);
 294                 hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
 295
 296                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 297                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 298         }
 299
 300         /* calculate size of additional header segments (AHSs) */
 301         hdrlength = ctask->hdr_len - sizeof(*hdr);
 302
 303         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 304         hdrlength /= ISCSI_PAD_LEN;
 305
 306         WARN_ON(hdrlength >= 256);
 307         hdr->hlength = hdrlength & 0xFF;
 308
 309         if (conn->session->tt->init_cmd_task(conn->ctask))
 310                 return EIO;
 311
 312         conn->scsicmd_pdus_cnt++;
 313         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x "
 314                 "len %d bidi_len %d cmdsn %d win %d]\n",
 315                 scsi_bidi_cmnd(sc) ? "bidirectional" :
 316                      sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 317                 conn->id, sc, sc->cmnd[0], ctask->itt,
 318                 scsi_bufflen(sc), scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
 319                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 320         return 0;
 321 }
 322
 323 /**
 324  * iscsi_complete_command - return command back to scsi-ml
 325  * @ctask: iscsi cmd task
 326  *
 327  * Must be called with session lock.
 328  * This function returns the scsi command to scsi-ml and returns
 329  * the cmd task to the pool of available cmd tasks.
 330  */
 331 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
 332 {
 333         struct iscsi_conn *conn = ctask->conn;
 334         struct iscsi_session *session = conn->session;
 335         struct scsi_cmnd *sc = ctask->sc;
 336
 337         ctask->state = ISCSI_TASK_COMPLETED;
 338         ctask->sc = NULL;
 339         /* SCSI eh reuses commands to verify us */
 340         sc->SCp.ptr = NULL;
 341         if (conn->ctask == ctask)
 342                 conn->ctask = NULL;
 343         list_del_init(&ctask->running);
 344         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 345         sc->scsi_done(sc);
 346 }
 347
 348 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 349 {
 350         atomic_inc(&ctask->refcount);
 351 }
 352
 353 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 354 {
 355         if (atomic_dec_and_test(&ctask->refcount))
 356                 iscsi_complete_command(ctask);
 357 }
 358
 359 /*
 360  * session lock must be held
 361  */
 362 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 363                          int err)
 364 {
 365         struct scsi_cmnd *sc;
 366
 367         sc = ctask->sc;
 368         if (!sc)
 369                 return;
 370
 371         if (ctask->state == ISCSI_TASK_PENDING)
 372                 /*
 373                  * cmd never made it to the xmit thread, so we should not count
 374                  * the cmd in the sequencing
 375                  */
 376                 conn->session->queued_cmdsn--;
 377         else
 378                 conn->session->tt->cleanup_cmd_task(conn, ctask);
 379
 380         sc->result = err;
 381         if (!scsi_bidi_cmnd(sc))
 382                 scsi_set_resid(sc, scsi_bufflen(sc));
 383         else {
 384                 scsi_out(sc)->resid = scsi_out(sc)->length;
 385                 scsi_in(sc)->resid = scsi_in(sc)->length;
 386         }
 387         if (conn->ctask == ctask)
 388                 conn->ctask = NULL;
 389         /* release ref from queuecommand */
 390         __iscsi_put_ctask(ctask);
 391 }
 392
 393 /**
 394  * iscsi_free_mgmt_task - return mgmt task back to pool
 395  * @conn: iscsi connection
 396  * @mtask: mtask
 397  *
 398  * Must be called with session lock.
 399  */
 400 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
 401                           struct iscsi_mgmt_task *mtask)
 402 {
 403         list_del_init(&mtask->running);
 404         if (conn->login_mtask == mtask)
 405                 return;
 406
 407         if (conn->ping_mtask == mtask)
 408                 conn->ping_mtask = NULL;
 409         __kfifo_put(conn->session->mgmtpool.queue,
 410                     (void*)&mtask, sizeof(void*));
 411 }
 412 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
 413
 414 static struct iscsi_mgmt_task *
 415 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 416                       char *data, uint32_t data_size)
 417 {
 418         struct iscsi_session *session = conn->session;
 419         struct iscsi_mgmt_task *mtask;
 420
 421         if (session->state == ISCSI_STATE_TERMINATE)
 422                 return NULL;
 423
 424         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 425             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 426                 /*
 427                  * Login and Text are sent serially, in
 428                  * request-followed-by-response sequence.
 429                  * Same mtask can be used. Same ITT must be used.
 430                  * Note that login_mtask is preallocated at conn_create().
 431                  */
 432                 mtask = conn->login_mtask;
 433         else {
 434                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 435                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 436
 437                 if (!__kfifo_get(session->mgmtpool.queue,
 438                                  (void*)&mtask, sizeof(void*)))
 439                         return NULL;
 440         }
 441
 442         if (data_size) {
 443                 memcpy(mtask->data, data, data_size);
 444                 mtask->data_count = data_size;
 445         } else
 446                 mtask->data_count = 0;
 447
 448         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 449         INIT_LIST_HEAD(&mtask->running);
 450         list_add_tail(&mtask->running, &conn->mgmtqueue);
 451         return mtask;
 452 }
 453
 454 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 455                         char *data, uint32_t data_size)
 456 {
 457         struct iscsi_conn *conn = cls_conn->dd_data;
 458         struct iscsi_session *session = conn->session;
 459         int err = 0;
 460
 461         spin_lock_bh(&session->lock);
 462         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 463                 err = -EPERM;
 464         spin_unlock_bh(&session->lock);
 465         scsi_queue_work(session->host, &conn->xmitwork);
 466         return err;
 467 }
 468 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 469
 470 /**
 471  * iscsi_cmd_rsp - SCSI Command Response processing
 472  * @conn: iscsi connection
 473  * @hdr: iscsi header
 474  * @ctask: scsi command task
 475  * @data: cmd data buffer
 476  * @datalen: len of buffer
 477  *
 478  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 479  * then completes the command and task.
 480  **/
 481 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 482                                struct iscsi_cmd_task *ctask, char *data,
 483                                int datalen)
 484 {
 485         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 486         struct iscsi_session *session = conn->session;
 487         struct scsi_cmnd *sc = ctask->sc;
 488
 489         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 490         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 491
 492         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 493
 494         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 495                 sc->result = DID_ERROR << 16;
 496                 goto out;
 497         }
 498
 499         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 500                 uint16_t senselen;
 501
 502                 if (datalen < 2) {
 503 invalid_datalen:
 504                         iscsi_conn_printk(KERN_ERR,  conn,
 505                                          "Got CHECK_CONDITION but invalid data "
 506                                          "buffer size of %d\n", datalen);
 507                         sc->result = DID_BAD_TARGET << 16;
 508                         goto out;
 509                 }
 510
 511                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
 512                 if (datalen < senselen)
 513                         goto invalid_datalen;
 514
 515                 memcpy(sc->sense_buffer, data + 2,
 516                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 517                 debug_scsi("copied %d bytes of sense\n",
 518                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 519         }
 520
 521         if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 522                            ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
 523                 int res_count = be32_to_cpu(rhdr->bi_residual_count);
 524
 525                 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
 526                                 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
 527                                  res_count <= scsi_in(sc)->length))
 528                         scsi_in(sc)->resid = res_count;
 529                 else
 530                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 531         }
 532
 533         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 534                            ISCSI_FLAG_CMD_OVERFLOW)) {
 535                 int res_count = be32_to_cpu(rhdr->residual_count);
 536
 537                 if (res_count > 0 &&
 538                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 539                      res_count <= scsi_bufflen(sc)))
 540                         /* write side for bidi or uni-io set_resid */
 541                         scsi_set_resid(sc, res_count);
 542                 else
 543                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 544         }
 545 out:
 546         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 547                    (long)sc, sc->result, ctask->itt);
 548         conn->scsirsp_pdus_cnt++;
 549
 550         __iscsi_put_ctask(ctask);
 551 }
 552
 553 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 554 {
 555         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 556
 557         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 558         conn->tmfrsp_pdus_cnt++;
 559
 560         if (conn->tmf_state != TMF_QUEUED)
 561                 return;
 562
 563         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 564                 conn->tmf_state = TMF_SUCCESS;
 565         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 566                 conn->tmf_state = TMF_NOT_FOUND;
 567         else
 568                 conn->tmf_state = TMF_FAILED;
 569         wake_up(&conn->ehwait);
 570 }
 571
 572 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 573 {
 574         struct iscsi_nopout hdr;
 575         struct iscsi_mgmt_task *mtask;
 576
 577         if (!rhdr && conn->ping_mtask)
 578                 return;
 579
 580         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 581         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 582         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 583
 584         if (rhdr) {
 585                 memcpy(hdr.lun, rhdr->lun, 8);
 586                 hdr.ttt = rhdr->ttt;
 587                 hdr.itt = RESERVED_ITT;
 588         } else
 589                 hdr.ttt = RESERVED_ITT;
 590
 591         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 592         if (!mtask) {
 593                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 594                 return;
 595         }
 596
 597         /* only track our nops */
 598         if (!rhdr) {
 599                 conn->ping_mtask = mtask;
 600                 conn->last_ping = jiffies;
 601         }
 602         scsi_queue_work(conn->session->host, &conn->xmitwork);
 603 }
 604
 605 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 606                                char *data, int datalen)
 607 {
 608         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 609         struct iscsi_hdr rejected_pdu;
 610         uint32_t itt;
 611
 612         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 613
 614         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 615                 if (ntoh24(reject->dlength) > datalen)
 616                         return ISCSI_ERR_PROTO;
 617
 618                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 619                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 620                         itt = get_itt(rejected_pdu.itt);
 621                         iscsi_conn_printk(KERN_ERR, conn,
 622                                           "itt 0x%x had pdu (op 0x%x) rejected "
 623                                           "due to DataDigest error.\n", itt,
 624                                           rejected_pdu.opcode);
 625                 }
 626         }
 627         return 0;
 628 }
 629
 630 /**
 631  * __iscsi_complete_pdu - complete pdu
 632  * @conn: iscsi conn
 633  * @hdr: iscsi header
 634  * @data: data buffer
 635  * @datalen: len of data buffer
 636  *
 637  * Completes pdu processing by freeing any resources allocated at
 638  * queuecommand or send generic. session lock must be held and verify
 639  * itt must have been called.
 640  */
 641 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 642                                 char *data, int datalen)
 643 {
 644         struct iscsi_session *session = conn->session;
 645         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 646         struct iscsi_cmd_task *ctask;
 647         struct iscsi_mgmt_task *mtask;
 648         uint32_t itt;
 649
 650         conn->last_recv = jiffies;
 651         if (hdr->itt != RESERVED_ITT)
 652                 itt = get_itt(hdr->itt);
 653         else
 654                 itt = ~0U;
 655
 656         if (itt < session->cmds_max) {
 657                 ctask = session->cmds[itt];
 658
 659                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 660                            opcode, conn->id, ctask->itt, datalen);
 661
 662                 switch(opcode) {
 663                 case ISCSI_OP_SCSI_CMD_RSP:
 664                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 665                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 666                                            datalen);
 667                         break;
 668                 case ISCSI_OP_SCSI_DATA_IN:
 669                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 670                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 671                                 conn->scsirsp_pdus_cnt++;
 672                                 __iscsi_put_ctask(ctask);
 673                         }
 674                         break;
 675                 case ISCSI_OP_R2T:
 676                         /* LLD handles this for now */
 677                         break;
 678                 default:
 679                         rc = ISCSI_ERR_BAD_OPCODE;
 680                         break;
 681                 }
 682         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 683                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 684                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 685
 686                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 687                            opcode, conn->id, mtask->itt, datalen);
 688
 689                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 690                 switch(opcode) {
 691                 case ISCSI_OP_LOGOUT_RSP:
 692                         if (datalen) {
 693                                 rc = ISCSI_ERR_PROTO;
 694                                 break;
 695                         }
 696                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 697                         /* fall through */
 698                 case ISCSI_OP_LOGIN_RSP:
 699                 case ISCSI_OP_TEXT_RSP:
 700                         /*
 701                          * login related PDU's exp_statsn is handled in
 702                          * userspace
 703                          */
 704                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 705                                 rc = ISCSI_ERR_CONN_FAILED;
 706                         iscsi_free_mgmt_task(conn, mtask);
 707                         break;
 708                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 709                         if (datalen) {
 710                                 rc = ISCSI_ERR_PROTO;
 711                                 break;
 712                         }
 713
 714                         iscsi_tmf_rsp(conn, hdr);
 715                         iscsi_free_mgmt_task(conn, mtask);
 716                         break;
 717                 case ISCSI_OP_NOOP_IN:
 718                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 719                             datalen) {
 720                                 rc = ISCSI_ERR_PROTO;
 721                                 break;
 722                         }
 723                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 724
 725                         if (conn->ping_mtask != mtask) {
 726                                 /*
 727                                  * If this is not in response to one of our
 728                                  * nops then it must be from userspace.
 729                                  */
 730                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 731                                                    datalen))
 732                                         rc = ISCSI_ERR_CONN_FAILED;
 733                         }
 734                         iscsi_free_mgmt_task(conn, mtask);
 735                         break;
 736                 default:
 737                         rc = ISCSI_ERR_BAD_OPCODE;
 738                         break;
 739                 }
 740         } else if (itt == ~0U) {
 741                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 742
 743                 switch(opcode) {
 744                 case ISCSI_OP_NOOP_IN:
 745                         if (datalen) {
 746                                 rc = ISCSI_ERR_PROTO;
 747                                 break;
 748                         }
 749
 750                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 751                                 break;
 752
 753                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 754                         break;
 755                 case ISCSI_OP_REJECT:
 756                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 757                         break;
 758                 case ISCSI_OP_ASYNC_EVENT:
 759                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 760                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 761                                 rc = ISCSI_ERR_CONN_FAILED;
 762                         break;
 763                 default:
 764                         rc = ISCSI_ERR_BAD_OPCODE;
 765                         break;
 766                 }
 767         } else
 768                 rc = ISCSI_ERR_BAD_ITT;
 769
 770         return rc;
 771 }
 772
 773 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 774                        char *data, int datalen)
 775 {
 776         int rc;
 777
 778         spin_lock(&conn->session->lock);
 779         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 780         spin_unlock(&conn->session->lock);
 781         return rc;
 782 }
 783 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 784
 785 /* verify itt (itt encoding: age+cid+itt) */
 786 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 787                      uint32_t *ret_itt)
 788 {
 789         struct iscsi_session *session = conn->session;
 790         struct iscsi_cmd_task *ctask;
 791         uint32_t itt;
 792
 793         if (hdr->itt != RESERVED_ITT) {
 794                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
 795                     (session->age << ISCSI_AGE_SHIFT)) {
 796                         iscsi_conn_printk(KERN_ERR, conn,
 797                                           "received itt %x expected session "
 798                                           "age (%x)\n", (__force u32)hdr->itt,
 799                                           session->age & ISCSI_AGE_MASK);
 800                         return ISCSI_ERR_BAD_ITT;
 801                 }
 802
 803                 itt = get_itt(hdr->itt);
 804         } else
 805                 itt = ~0U;
 806
 807         if (itt < session->cmds_max) {
 808                 ctask = session->cmds[itt];
 809
 810                 if (!ctask->sc) {
 811                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
 812                                           "with itt 0x%x\n", ctask->itt);
 813                         /* force drop */
 814                         return ISCSI_ERR_NO_SCSI_CMD;
 815                 }
 816
 817                 if (ctask->sc->SCp.phase != session->age) {
 818                         iscsi_conn_printk(KERN_ERR, conn,
 819                                           "iscsi: ctask's session age %d, "
 820                                           "expected %d\n", ctask->sc->SCp.phase,
 821                                           session->age);
 822                         return ISCSI_ERR_SESSION_FAILED;
 823                 }
 824         }
 825
 826         *ret_itt = itt;
 827         return 0;
 828 }
 829 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 830
 831 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 832 {
 833         struct iscsi_session *session = conn->session;
 834         unsigned long flags;
 835
 836         spin_lock_irqsave(&session->lock, flags);
 837         if (session->state == ISCSI_STATE_FAILED) {
 838                 spin_unlock_irqrestore(&session->lock, flags);
 839                 return;
 840         }
 841
 842         if (conn->stop_stage == 0)
 843                 session->state = ISCSI_STATE_FAILED;
 844         spin_unlock_irqrestore(&session->lock, flags);
 845         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 846         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 847         iscsi_conn_error(conn->cls_conn, err);
 848 }
 849 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 850
 851 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 852                              struct iscsi_mgmt_task *mtask)
 853 {
 854         struct iscsi_session *session = conn->session;
 855         struct iscsi_hdr *hdr = mtask->hdr;
 856         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 857
 858         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 859             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 860                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 861         /*
 862          * pre-format CmdSN for outgoing PDU.
 863          */
 864         nop->cmdsn = cpu_to_be32(session->cmdsn);
 865         if (hdr->itt != RESERVED_ITT) {
 866                 hdr->itt = build_itt(mtask->itt, session->age);
 867                 /*
 868                  * TODO: We always use immediate, so we never hit this.
 869                  * If we start to send tmfs or nops as non-immediate then
 870                  * we should start checking the cmdsn numbers for mgmt tasks.
 871                  */
 872                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 873                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 874                         session->queued_cmdsn++;
 875                         session->cmdsn++;
 876                 }
 877         }
 878
 879         if (session->tt->init_mgmt_task)
 880                 session->tt->init_mgmt_task(conn, mtask);
 881
 882         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 883                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 884                    mtask->data_count);
 885 }
 886
 887 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 888 {
 889         struct iscsi_hdr *hdr = conn->mtask->hdr;
 890         int rc;
 891
 892         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 893                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 894         spin_unlock_bh(&conn->session->lock);
 895
 896         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 897         spin_lock_bh(&conn->session->lock);
 898         if (rc)
 899                 return rc;
 900
 901         /* done with this in-progress mtask */
 902         conn->mtask = NULL;
 903         return 0;
 904 }
 905
 906 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 907 {
 908         struct iscsi_session *session = conn->session;
 909
 910         /*
 911          * Check for iSCSI window and take care of CmdSN wrap-around
 912          */
 913         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 914                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 915                            "CmdSN %u/%u\n", session->exp_cmdsn,
 916                            session->max_cmdsn, session->cmdsn,
 917                            session->queued_cmdsn);
 918                 return -ENOSPC;
 919         }
 920         return 0;
 921 }
 922
 923 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 924 {
 925         struct iscsi_cmd_task *ctask = conn->ctask;
 926         int rc;
 927
 928         __iscsi_get_ctask(ctask);
 929         spin_unlock_bh(&conn->session->lock);
 930         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 931         spin_lock_bh(&conn->session->lock);
 932         __iscsi_put_ctask(ctask);
 933         if (!rc)
 934                 /* done with this ctask */
 935                 conn->ctask = NULL;
 936         return rc;
 937 }
 938
 939 /**
 940  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 941  * @ctask: ctask to requeue
 942  *
 943  * LLDs that need to run a ctask from the session workqueue should call
 944  * this. The session lock must be held.
 945  */
 946 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 947 {
 948         struct iscsi_conn *conn = ctask->conn;
 949
 950         list_move_tail(&ctask->running, &conn->requeue);
 951         scsi_queue_work(conn->session->host, &conn->xmitwork);
 952 }
 953 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 954
 955 /**
 956  * iscsi_data_xmit - xmit any command into the scheduled connection
 957  * @conn: iscsi connection
 958  *
 959  * Notes:
 960  *      The function can return -EAGAIN in which case the caller must
 961  *      re-schedule it again later or recover. '0' return code means
 962  *      successful xmit.
 963  **/
 964 static int iscsi_data_xmit(struct iscsi_conn *conn)
 965 {
 966         int rc = 0;
 967
 968         spin_lock_bh(&conn->session->lock);
 969         if (unlikely(conn->suspend_tx)) {
 970                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 971                 spin_unlock_bh(&conn->session->lock);
 972                 return -ENODATA;
 973         }
 974
 975         if (conn->ctask) {
 976                 rc = iscsi_xmit_ctask(conn);
 977                 if (rc)
 978                         goto again;
 979         }
 980
 981         if (conn->mtask) {
 982                 rc = iscsi_xmit_mtask(conn);
 983                 if (rc)
 984                         goto again;
 985         }
 986
 987         /*
 988          * process mgmt pdus like nops before commands since we should
 989          * only have one nop-out as a ping from us and targets should not
 990          * overflow us with nop-ins
 991          */
 992 check_mgmt:
 993         while (!list_empty(&conn->mgmtqueue)) {
 994                 conn->mtask = list_entry(conn->mgmtqueue.next,
 995                                          struct iscsi_mgmt_task, running);
 996                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 997                         iscsi_free_mgmt_task(conn, conn->mtask);
 998                         conn->mtask = NULL;
 999                         continue;
1000                 }
1001
1002                 iscsi_prep_mtask(conn, conn->mtask);
1003                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
1004                 rc = iscsi_xmit_mtask(conn);
1005                 if (rc)
1006                         goto again;
1007         }
1008
1009         /* process pending command queue */
1010         while (!list_empty(&conn->xmitqueue)) {
1011                 if (conn->tmf_state == TMF_QUEUED)
1012                         break;
1013
1014                 conn->ctask = list_entry(conn->xmitqueue.next,
1015                                          struct iscsi_cmd_task, running);
1016                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1017                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
1018                         continue;
1019                 }
1020                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
1021                         fail_command(conn, conn->ctask, DID_ABORT << 16);
1022                         continue;
1023                 }
1024
1025                 conn->ctask->state = ISCSI_TASK_RUNNING;
1026                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
1027                 rc = iscsi_xmit_ctask(conn);
1028                 if (rc)
1029                         goto again;
1030                 /*
1031                  * we could continuously get new ctask requests so
1032                  * we need to check the mgmt queue for nops that need to
1033                  * be sent to aviod starvation
1034                  */
1035                 if (!list_empty(&conn->mgmtqueue))
1036                         goto check_mgmt;
1037         }
1038
1039         while (!list_empty(&conn->requeue)) {
1040                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
1041                         break;
1042
1043                 /*
1044                  * we always do fastlogout - conn stop code will clean up.
1045                  */
1046                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1047                         break;
1048
1049                 conn->ctask = list_entry(conn->requeue.next,
1050                                          struct iscsi_cmd_task, running);
1051                 conn->ctask->state = ISCSI_TASK_RUNNING;
1052                 list_move_tail(conn->requeue.next, &conn->run_list);
1053                 rc = iscsi_xmit_ctask(conn);
1054                 if (rc)
1055                         goto again;
1056                 if (!list_empty(&conn->mgmtqueue))
1057                         goto check_mgmt;
1058         }
1059         spin_unlock_bh(&conn->session->lock);
1060         return -ENODATA;
1061
1062 again:
1063         if (unlikely(conn->suspend_tx))
1064                 rc = -ENODATA;
1065         spin_unlock_bh(&conn->session->lock);
1066         return rc;
1067 }
1068
1069 static void iscsi_xmitworker(struct work_struct *work)
1070 {
1071         struct iscsi_conn *conn =
1072                 container_of(work, struct iscsi_conn, xmitwork);
1073         int rc;
1074         /*
1075          * serialize Xmit worker on a per-connection basis.
1076          */
1077         do {
1078                 rc = iscsi_data_xmit(conn);
1079         } while (rc >= 0 || rc == -EAGAIN);
1080 }
1081
1082 enum {
1083         FAILURE_BAD_HOST = 1,
1084         FAILURE_SESSION_FAILED,
1085         FAILURE_SESSION_FREED,
1086         FAILURE_WINDOW_CLOSED,
1087         FAILURE_OOM,
1088         FAILURE_SESSION_TERMINATE,
1089         FAILURE_SESSION_IN_RECOVERY,
1090         FAILURE_SESSION_RECOVERY_TIMEOUT,
1091         FAILURE_SESSION_LOGGING_OUT,
1092         FAILURE_SESSION_NOT_READY,
1093 };
1094
1095 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1096 {
1097         struct Scsi_Host *host;
1098         int reason = 0;
1099         struct iscsi_session *session;
1100         struct iscsi_conn *conn;
1101         struct iscsi_cmd_task *ctask = NULL;
1102
1103         sc->scsi_done = done;
1104         sc->result = 0;
1105         sc->SCp.ptr = NULL;
1106
1107         host = sc->device->host;
1108         spin_unlock(host->host_lock);
1109
1110         session = iscsi_hostdata(host->hostdata);
1111         spin_lock(&session->lock);
1112
1113         reason = iscsi_session_chkready(session_to_cls(session));
1114         if (reason) {
1115                 sc->result = reason;
1116                 goto fault;
1117         }
1118
1119         /*
1120          * ISCSI_STATE_FAILED is a temp. state. The recovery
1121          * code will decide what is best to do with command queued
1122          * during this time
1123          */
1124         if (session->state != ISCSI_STATE_LOGGED_IN &&
1125             session->state != ISCSI_STATE_FAILED) {
1126                 /*
1127                  * to handle the race between when we set the recovery state
1128                  * and block the session we requeue here (commands could
1129                  * be entering our queuecommand while a block is starting
1130                  * up because the block code is not locked)
1131                  */
1132                 switch (session->state) {
1133                 case ISCSI_STATE_IN_RECOVERY:
1134                         reason = FAILURE_SESSION_IN_RECOVERY;
1135                         sc->result = DID_IMM_RETRY << 16;
1136                         break;
1137                 case ISCSI_STATE_LOGGING_OUT:
1138                         reason = FAILURE_SESSION_LOGGING_OUT;
1139                         sc->result = DID_IMM_RETRY << 16;
1140                         break;
1141                 case ISCSI_STATE_RECOVERY_FAILED:
1142                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1143                         sc->result = DID_NO_CONNECT << 16;
1144                         break;
1145                 case ISCSI_STATE_TERMINATE:
1146                         reason = FAILURE_SESSION_TERMINATE;
1147                         sc->result = DID_NO_CONNECT << 16;
1148                         break;
1149                 default:
1150                         reason = FAILURE_SESSION_FREED;
1151                         sc->result = DID_NO_CONNECT << 16;
1152                 }
1153                 goto fault;
1154         }
1155
1156         conn = session->leadconn;
1157         if (!conn) {
1158                 reason = FAILURE_SESSION_FREED;
1159                 sc->result = DID_NO_CONNECT << 16;
1160                 goto fault;
1161         }
1162
1163         if (iscsi_check_cmdsn_window_closed(conn)) {
1164                 reason = FAILURE_WINDOW_CLOSED;
1165                 goto reject;
1166         }
1167
1168         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1169                          sizeof(void*))) {
1170                 reason = FAILURE_OOM;
1171                 goto reject;
1172         }
1173         session->queued_cmdsn++;
1174
1175         sc->SCp.phase = session->age;
1176         sc->SCp.ptr = (char *)ctask;
1177
1178         atomic_set(&ctask->refcount, 1);
1179         ctask->state = ISCSI_TASK_PENDING;
1180         ctask->conn = conn;
1181         ctask->sc = sc;
1182         INIT_LIST_HEAD(&ctask->running);
1183
1184         list_add_tail(&ctask->running, &conn->xmitqueue);
1185         spin_unlock(&session->lock);
1186
1187         scsi_queue_work(host, &conn->xmitwork);
1188         spin_lock(host->host_lock);
1189         return 0;
1190
1191 reject:
1192         spin_unlock(&session->lock);
1193         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1194         spin_lock(host->host_lock);
1195         return SCSI_MLQUEUE_HOST_BUSY;
1196
1197 fault:
1198         spin_unlock(&session->lock);
1199         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1200         if (!scsi_bidi_cmnd(sc))
1201                 scsi_set_resid(sc, scsi_bufflen(sc));
1202         else {
1203                 scsi_out(sc)->resid = scsi_out(sc)->length;
1204                 scsi_in(sc)->resid = scsi_in(sc)->length;
1205         }
1206         sc->scsi_done(sc);
1207         spin_lock(host->host_lock);
1208         return 0;
1209 }
1210 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1211
1212 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1213 {
1214         if (depth > ISCSI_MAX_CMD_PER_LUN)
1215                 depth = ISCSI_MAX_CMD_PER_LUN;
1216         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1217         return sdev->queue_depth;
1218 }
1219 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1220
1221 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1222 {
1223         struct iscsi_session *session = class_to_transport_session(cls_session);
1224
1225         spin_lock_bh(&session->lock);
1226         if (session->state != ISCSI_STATE_LOGGED_IN) {
1227                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1228                 if (session->leadconn)
1229                         wake_up(&session->leadconn->ehwait);
1230         }
1231         spin_unlock_bh(&session->lock);
1232 }
1233 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1234
1235 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1236 {
1237         struct Scsi_Host *host = sc->device->host;
1238         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1239         struct iscsi_conn *conn = session->leadconn;
1240
1241         mutex_lock(&session->eh_mutex);
1242         spin_lock_bh(&session->lock);
1243         if (session->state == ISCSI_STATE_TERMINATE) {
1244 failed:
1245                 debug_scsi("failing host reset: session terminated "
1246                            "[CID %d age %d]\n", conn->id, session->age);
1247                 spin_unlock_bh(&session->lock);
1248                 mutex_unlock(&session->eh_mutex);
1249                 return FAILED;
1250         }
1251
1252         spin_unlock_bh(&session->lock);
1253         mutex_unlock(&session->eh_mutex);
1254         /*
1255          * we drop the lock here but the leadconn cannot be destoyed while
1256          * we are in the scsi eh
1257          */
1258         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1259
1260         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1261         wait_event_interruptible(conn->ehwait,
1262                                  session->state == ISCSI_STATE_TERMINATE ||
1263                                  session->state == ISCSI_STATE_LOGGED_IN ||
1264                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1265         if (signal_pending(current))
1266                 flush_signals(current);
1267
1268         mutex_lock(&session->eh_mutex);
1269         spin_lock_bh(&session->lock);
1270         if (session->state == ISCSI_STATE_LOGGED_IN)
1271                 iscsi_session_printk(KERN_INFO, session,
1272                                      "host reset succeeded\n");
1273         else
1274                 goto failed;
1275         spin_unlock_bh(&session->lock);
1276         mutex_unlock(&session->eh_mutex);
1277         return SUCCESS;
1278 }
1279 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1280
1281 static void iscsi_tmf_timedout(unsigned long data)
1282 {
1283         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1284         struct iscsi_session *session = conn->session;
1285
1286         spin_lock(&session->lock);
1287         if (conn->tmf_state == TMF_QUEUED) {
1288                 conn->tmf_state = TMF_TIMEDOUT;
1289                 debug_scsi("tmf timedout\n");
1290                 /* unblock eh_abort() */
1291                 wake_up(&conn->ehwait);
1292         }
1293         spin_unlock(&session->lock);
1294 }
1295
1296 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1297                                    struct iscsi_tm *hdr, int age,
1298                                    int timeout)
1299 {
1300         struct iscsi_session *session = conn->session;
1301         struct iscsi_mgmt_task *mtask;
1302
1303         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1304                                       NULL, 0);
1305         if (!mtask) {
1306                 spin_unlock_bh(&session->lock);
1307                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1308                 spin_lock_bh(&session->lock);
1309                 debug_scsi("tmf exec failure\n");
1310                 return -EPERM;
1311         }
1312         conn->tmfcmd_pdus_cnt++;
1313         conn->tmf_timer.expires = timeout * HZ + jiffies;
1314         conn->tmf_timer.function = iscsi_tmf_timedout;
1315         conn->tmf_timer.data = (unsigned long)conn;
1316         add_timer(&conn->tmf_timer);
1317         debug_scsi("tmf set timeout\n");
1318
1319         spin_unlock_bh(&session->lock);
1320         mutex_unlock(&session->eh_mutex);
1321         scsi_queue_work(session->host, &conn->xmitwork);
1322
1323         /*
1324          * block eh thread until:
1325          *
1326          * 1) tmf response
1327          * 2) tmf timeout
1328          * 3) session is terminated or restarted or userspace has
1329          * given up on recovery
1330          */
1331         wait_event_interruptible(conn->ehwait, age != session->age ||
1332                                  session->state != ISCSI_STATE_LOGGED_IN ||
1333                                  conn->tmf_state != TMF_QUEUED);
1334         if (signal_pending(current))
1335                 flush_signals(current);
1336         del_timer_sync(&conn->tmf_timer);
1337
1338         mutex_lock(&session->eh_mutex);
1339         spin_lock_bh(&session->lock);
1340         /* if the session drops it will clean up the mtask */
1341         if (age != session->age ||
1342             session->state != ISCSI_STATE_LOGGED_IN)
1343                 return -ENOTCONN;
1344         return 0;
1345 }
1346
1347 /*
1348  * Fail commands. session lock held and recv side suspended and xmit
1349  * thread flushed
1350  */
1351 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1352                               int error)
1353 {
1354         struct iscsi_cmd_task *ctask, *tmp;
1355
1356         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1357                 conn->ctask = NULL;
1358
1359         /* flush pending */
1360         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1361                 if (lun == ctask->sc->device->lun || lun == -1) {
1362                         debug_scsi("failing pending sc %p itt 0x%x\n",
1363                                    ctask->sc, ctask->itt);
1364                         fail_command(conn, ctask, error << 16);
1365                 }
1366         }
1367
1368         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1369                 if (lun == ctask->sc->device->lun || lun == -1) {
1370                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1371                                    ctask->sc, ctask->itt);
1372                         fail_command(conn, ctask, error << 16);
1373                 }
1374         }
1375
1376         /* fail all other running */
1377         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1378                 if (lun == ctask->sc->device->lun || lun == -1) {
1379                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1380                                    ctask->sc, ctask->itt);
1381                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1382                 }
1383         }
1384 }
1385
1386 static void iscsi_suspend_tx(struct iscsi_conn *conn)
1387 {
1388         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1389         scsi_flush_work(conn->session->host);
1390 }
1391
1392 static void iscsi_start_tx(struct iscsi_conn *conn)
1393 {
1394         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1395         scsi_queue_work(conn->session->host, &conn->xmitwork);
1396 }
1397
1398 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1399 {
1400         struct iscsi_cls_session *cls_session;
1401         struct iscsi_session *session;
1402         struct iscsi_conn *conn;
1403         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1404
1405         cls_session = starget_to_session(scsi_target(scmd->device));
1406         session = class_to_transport_session(cls_session);
1407
1408         debug_scsi("scsi cmd %p timedout\n", scmd);
1409
1410         spin_lock(&session->lock);
1411         if (session->state != ISCSI_STATE_LOGGED_IN) {
1412                 /*
1413                  * We are probably in the middle of iscsi recovery so let
1414                  * that complete and handle the error.
1415                  */
1416                 rc = EH_RESET_TIMER;
1417                 goto done;
1418         }
1419
1420         conn = session->leadconn;
1421         if (!conn) {
1422                 /* In the middle of shuting down */
1423                 rc = EH_RESET_TIMER;
1424                 goto done;
1425         }
1426
1427         if (!conn->recv_timeout && !conn->ping_timeout)
1428                 goto done;
1429         /*
1430          * if the ping timedout then we are in the middle of cleaning up
1431          * and can let the iscsi eh handle it
1432          */
1433         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1434                             (conn->ping_timeout * HZ), jiffies))
1435                 rc = EH_RESET_TIMER;
1436         /*
1437          * if we are about to check the transport then give the command
1438          * more time
1439          */
1440         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1441                            jiffies))
1442                 rc = EH_RESET_TIMER;
1443         /* if in the middle of checking the transport then give us more time */
1444         if (conn->ping_mtask)
1445                 rc = EH_RESET_TIMER;
1446 done:
1447         spin_unlock(&session->lock);
1448         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1449         return rc;
1450 }
1451
1452 static void iscsi_check_transport_timeouts(unsigned long data)
1453 {
1454         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1455         struct iscsi_session *session = conn->session;
1456         unsigned long timeout, next_timeout = 0, last_recv;
1457
1458         spin_lock(&session->lock);
1459         if (session->state != ISCSI_STATE_LOGGED_IN)
1460                 goto done;
1461
1462         timeout = conn->recv_timeout;
1463         if (!timeout)
1464                 goto done;
1465
1466         timeout *= HZ;
1467         last_recv = conn->last_recv;
1468         if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
1469                            jiffies)) {
1470                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1471                                   "expired, last rx %lu, last ping %lu, "
1472                                   "now %lu\n", conn->ping_timeout, last_recv,
1473                                   conn->last_ping, jiffies);
1474                 spin_unlock(&session->lock);
1475                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1476                 return;
1477         }
1478
1479         if (time_before_eq(last_recv + timeout, jiffies)) {
1480                 if (time_before_eq(conn->last_ping, last_recv)) {
1481                         /* send a ping to try to provoke some traffic */
1482                         debug_scsi("Sending nopout as ping on conn %p\n", conn);
1483                         iscsi_send_nopout(conn, NULL);
1484                 }
1485                 next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
1486         } else
1487                 next_timeout = last_recv + timeout;
1488
1489         debug_scsi("Setting next tmo %lu\n", next_timeout);
1490         mod_timer(&conn->transport_timer, next_timeout);
1491 done:
1492         spin_unlock(&session->lock);
1493 }
1494
1495 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1496                                       struct iscsi_tm *hdr)
1497 {
1498         memset(hdr, 0, sizeof(*hdr));
1499         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1500         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1501         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1502         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1503         hdr->rtt = ctask->hdr->itt;
1504         hdr->refcmdsn = ctask->hdr->cmdsn;
1505 }
1506
1507 int iscsi_eh_abort(struct scsi_cmnd *sc)
1508 {
1509         struct Scsi_Host *host = sc->device->host;
1510         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1511         struct iscsi_conn *conn;
1512         struct iscsi_cmd_task *ctask;
1513         struct iscsi_tm *hdr;
1514         int rc, age;
1515
1516         mutex_lock(&session->eh_mutex);
1517         spin_lock_bh(&session->lock);
1518         /*
1519          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1520          * got the command.
1521          */
1522         if (!sc->SCp.ptr) {
1523                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1524                 spin_unlock_bh(&session->lock);
1525                 mutex_unlock(&session->eh_mutex);
1526                 return SUCCESS;
1527         }
1528
1529         /*
1530          * If we are not logged in or we have started a new session
1531          * then let the host reset code handle this
1532          */
1533         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1534             sc->SCp.phase != session->age) {
1535                 spin_unlock_bh(&session->lock);
1536                 mutex_unlock(&session->eh_mutex);
1537                 return FAILED;
1538         }
1539
1540         conn = session->leadconn;
1541         conn->eh_abort_cnt++;
1542         age = session->age;
1543
1544         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1545         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1546
1547         /* ctask completed before time out */
1548         if (!ctask->sc) {
1549                 debug_scsi("sc completed while abort in progress\n");
1550                 goto success;
1551         }
1552
1553         if (ctask->state == ISCSI_TASK_PENDING) {
1554                 fail_command(conn, ctask, DID_ABORT << 16);
1555                 goto success;
1556         }
1557
1558         /* only have one tmf outstanding at a time */
1559         if (conn->tmf_state != TMF_INITIAL)
1560                 goto failed;
1561         conn->tmf_state = TMF_QUEUED;
1562
1563         hdr = &conn->tmhdr;
1564         iscsi_prep_abort_task_pdu(ctask, hdr);
1565
1566         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1567                 rc = FAILED;
1568                 goto failed;
1569         }
1570
1571         switch (conn->tmf_state) {
1572         case TMF_SUCCESS:
1573                 spin_unlock_bh(&session->lock);
1574                 iscsi_suspend_tx(conn);
1575                 /*
1576                  * clean up task if aborted. grab the recv lock as a writer
1577                  */
1578                 write_lock_bh(conn->recv_lock);
1579                 spin_lock(&session->lock);
1580                 fail_command(conn, ctask, DID_ABORT << 16);
1581                 conn->tmf_state = TMF_INITIAL;
1582                 spin_unlock(&session->lock);
1583                 write_unlock_bh(conn->recv_lock);
1584                 iscsi_start_tx(conn);
1585                 goto success_unlocked;
1586         case TMF_TIMEDOUT:
1587                 spin_unlock_bh(&session->lock);
1588                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1589                 goto failed_unlocked;
1590         case TMF_NOT_FOUND:
1591                 if (!sc->SCp.ptr) {
1592                         conn->tmf_state = TMF_INITIAL;
1593                         /* ctask completed before tmf abort response */
1594                         debug_scsi("sc completed while abort in progress\n");
1595                         goto success;
1596                 }
1597                 /* fall through */
1598         default:
1599                 conn->tmf_state = TMF_INITIAL;
1600                 goto failed;
1601         }
1602
1603 success:
1604         spin_unlock_bh(&session->lock);
1605 success_unlocked:
1606         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1607         mutex_unlock(&session->eh_mutex);
1608         return SUCCESS;
1609
1610 failed:
1611         spin_unlock_bh(&session->lock);
1612 failed_unlocked:
1613         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1614                     ctask ? ctask->itt : 0);
1615         mutex_unlock(&session->eh_mutex);
1616         return FAILED;
1617 }
1618 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1619
1620 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1621 {
1622         memset(hdr, 0, sizeof(*hdr));
1623         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1624         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1625         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1626         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1627         hdr->rtt = RESERVED_ITT;
1628 }
1629
1630 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1631 {
1632         struct Scsi_Host *host = sc->device->host;
1633         struct iscsi_session *session = iscsi_hostdata(host->hostdata);
1634         struct iscsi_conn *conn;
1635         struct iscsi_tm *hdr;
1636         int rc = FAILED;
1637
1638         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1639
1640         mutex_lock(&session->eh_mutex);
1641         spin_lock_bh(&session->lock);
1642         /*
1643          * Just check if we are not logged in. We cannot check for
1644          * the phase because the reset could come from a ioctl.
1645          */
1646         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1647                 goto unlock;
1648         conn = session->leadconn;
1649
1650         /* only have one tmf outstanding at a time */
1651         if (conn->tmf_state != TMF_INITIAL)
1652                 goto unlock;
1653         conn->tmf_state = TMF_QUEUED;
1654
1655         hdr = &conn->tmhdr;
1656         iscsi_prep_lun_reset_pdu(sc, hdr);
1657
1658         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1659                                     session->lu_reset_timeout)) {
1660                 rc = FAILED;
1661                 goto unlock;
1662         }
1663
1664         switch (conn->tmf_state) {
1665         case TMF_SUCCESS:
1666                 break;
1667         case TMF_TIMEDOUT:
1668                 spin_unlock_bh(&session->lock);
1669                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1670                 goto done;
1671         default:
1672                 conn->tmf_state = TMF_INITIAL;
1673                 goto unlock;
1674         }
1675
1676         rc = SUCCESS;
1677         spin_unlock_bh(&session->lock);
1678
1679         iscsi_suspend_tx(conn);
1680         /* need to grab the recv lock then session lock */
1681         write_lock_bh(conn->recv_lock);
1682         spin_lock(&session->lock);
1683         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1684         conn->tmf_state = TMF_INITIAL;
1685         spin_unlock(&session->lock);
1686         write_unlock_bh(conn->recv_lock);
1687
1688         iscsi_start_tx(conn);
1689         goto done;
1690
1691 unlock:
1692         spin_unlock_bh(&session->lock);
1693 done:
1694         debug_scsi("iscsi_eh_device_reset %s\n",
1695                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1696         mutex_unlock(&session->eh_mutex);
1697         return rc;
1698 }
1699 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1700
1701 /*
1702  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1703  * should be accessed via kfifo_{get,put} on q->queue.
1704  * Optionally, the caller can obtain the array of object pointers
1705  * by passing in a non-NULL @items pointer
1706  */
1707 int
1708 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1709 {
1710         int i, num_arrays = 1;
1711
1712         memset(q, 0, sizeof(*q));
1713
1714         q->max = max;
1715
1716         /* If the user passed an items pointer, he wants a copy of
1717          * the array. */
1718         if (items)
1719                 num_arrays++;
1720         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1721         if (q->pool == NULL)
1722                 goto enomem;
1723
1724         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1725                               GFP_KERNEL, NULL);
1726         if (q->queue == ERR_PTR(-ENOMEM))
1727                 goto enomem;
1728
1729         for (i = 0; i < max; i++) {
1730                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1731                 if (q->pool[i] == NULL) {
1732                         q->max = i;
1733                         goto enomem;
1734                 }
1735                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1736         }
1737
1738         if (items) {
1739                 *items = q->pool + max;
1740                 memcpy(*items, q->pool, max * sizeof(void *));
1741         }
1742
1743         return 0;
1744
1745 enomem:
1746         iscsi_pool_free(q);
1747         return -ENOMEM;
1748 }
1749 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1750
1751 void iscsi_pool_free(struct iscsi_pool *q)
1752 {
1753         int i;
1754
1755         for (i = 0; i < q->max; i++)
1756                 kfree(q->pool[i]);
1757         if (q->pool)
1758                 kfree(q->pool);
1759 }
1760 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1761
1762 /*
1763  * iSCSI Session's hostdata organization:
1764  *
1765  *    *------------------* <== hostdata_session(host->hostdata)
1766  *    | ptr to class sess|
1767  *    |------------------| <== iscsi_hostdata(host->hostdata)
1768  *    | iscsi_session    |
1769  *    *------------------*
1770  */
1771
1772 #define hostdata_privsize(_sz)  (sizeof(unsigned long) + _sz + \
1773                                  _sz % sizeof(unsigned long))
1774
1775 #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1776
1777 /**
1778  * iscsi_session_setup - create iscsi cls session and host and session
1779  * @scsit: scsi transport template
1780  * @iscsit: iscsi transport template
1781  * @cmds_max: scsi host can queue
1782  * @qdepth: scsi host cmds per lun
1783  * @cmd_task_size: LLD ctask private data size
1784  * @mgmt_task_size: LLD mtask private data size
1785  * @initial_cmdsn: initial CmdSN
1786  * @hostno: host no allocated
1787  *
1788  * This can be used by software iscsi_transports that allocate
1789  * a session per scsi host.
1790  **/
1791 struct iscsi_cls_session *
1792 iscsi_session_setup(struct iscsi_transport *iscsit,
1793                     struct scsi_transport_template *scsit,
1794                     uint16_t cmds_max, uint16_t qdepth,
1795                     int cmd_task_size, int mgmt_task_size,
1796                     uint32_t initial_cmdsn, uint32_t *hostno)
1797 {
1798         struct Scsi_Host *shost;
1799         struct iscsi_session *session;
1800         struct iscsi_cls_session *cls_session;
1801         int cmd_i;
1802
1803         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1804                 if (qdepth != 0)
1805                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1806                               "Queue depth must be between 1 and %d.\n",
1807                               qdepth, ISCSI_MAX_CMD_PER_LUN);
1808                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1809         }
1810
1811         if (!is_power_of_2(cmds_max) || cmds_max >= ISCSI_MGMT_ITT_OFFSET ||
1812             cmds_max < 2) {
1813                 if (cmds_max != 0)
1814                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1815                                "can_queue must be a power of 2 and between "
1816                                "2 and %d - setting to %d.\n", cmds_max,
1817                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1818                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1819         }
1820
1821         shost = scsi_host_alloc(iscsit->host_template,
1822                                 hostdata_privsize(sizeof(*session)));
1823         if (!shost)
1824                 return NULL;
1825
1826         /* the iscsi layer takes one task for reserve */
1827         shost->can_queue = cmds_max - 1;
1828         shost->cmd_per_lun = qdepth;
1829         shost->max_id = 1;
1830         shost->max_channel = 0;
1831         shost->max_lun = iscsit->max_lun;
1832         shost->max_cmd_len = iscsit->max_cmd_len;
1833         shost->transportt = scsit;
1834         shost->transportt->create_work_queue = 1;
1835         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1836         *hostno = shost->host_no;
1837
1838         session = iscsi_hostdata(shost->hostdata);
1839         memset(session, 0, sizeof(struct iscsi_session));
1840         session->host = shost;
1841         session->state = ISCSI_STATE_FREE;
1842         session->fast_abort = 1;
1843         session->lu_reset_timeout = 15;
1844         session->abort_timeout = 10;
1845         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1846         session->cmds_max = cmds_max;
1847         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1848         session->exp_cmdsn = initial_cmdsn + 1;
1849         session->max_cmdsn = initial_cmdsn + 1;
1850         session->max_r2t = 1;
1851         session->tt = iscsit;
1852         mutex_init(&session->eh_mutex);
1853
1854         /* initialize SCSI PDU commands pool */
1855         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1856                             (void***)&session->cmds,
1857                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1858                 goto cmdpool_alloc_fail;
1859
1860         /* pre-format cmds pool with ITT */
1861         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1862                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1863
1864                 if (cmd_task_size)
1865                         ctask->dd_data = &ctask[1];
1866                 ctask->itt = cmd_i;
1867                 INIT_LIST_HEAD(&ctask->running);
1868         }
1869
1870         spin_lock_init(&session->lock);
1871
1872         /* initialize immediate command pool */
1873         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1874                            (void***)&session->mgmt_cmds,
1875                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1876                 goto mgmtpool_alloc_fail;
1877
1878
1879         /* pre-format immediate cmds pool with ITT */
1880         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1881                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1882
1883                 if (mgmt_task_size)
1884                         mtask->dd_data = &mtask[1];
1885                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1886                 INIT_LIST_HEAD(&mtask->running);
1887         }
1888
1889         if (scsi_add_host(shost, NULL))
1890                 goto add_host_fail;
1891
1892         if (!try_module_get(iscsit->owner))
1893                 goto cls_session_fail;
1894
1895         cls_session = iscsi_create_session(shost, iscsit, 0);
1896         if (!cls_session)
1897                 goto module_put;
1898         *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1899
1900         return cls_session;
1901
1902 module_put:
1903         module_put(iscsit->owner);
1904 cls_session_fail:
1905         scsi_remove_host(shost);
1906 add_host_fail:
1907         iscsi_pool_free(&session->mgmtpool);
1908 mgmtpool_alloc_fail:
1909         iscsi_pool_free(&session->cmdpool);
1910 cmdpool_alloc_fail:
1911         scsi_host_put(shost);
1912         return NULL;
1913 }
1914 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1915
1916 /**
1917  * iscsi_session_teardown - destroy session, host, and cls_session
1918  * shost: scsi host
1919  *
1920  * This can be used by software iscsi_transports that allocate
1921  * a session per scsi host.
1922  **/
1923 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1924 {
1925         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1926         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1927         struct module *owner = cls_session->transport->owner;
1928
1929         iscsi_remove_session(cls_session);
1930         scsi_remove_host(shost);
1931
1932         iscsi_pool_free(&session->mgmtpool);
1933         iscsi_pool_free(&session->cmdpool);
1934
1935         kfree(session->password);
1936         kfree(session->password_in);
1937         kfree(session->username);
1938         kfree(session->username_in);
1939         kfree(session->targetname);
1940         kfree(session->netdev);
1941         kfree(session->hwaddress);
1942         kfree(session->initiatorname);
1943
1944         iscsi_free_session(cls_session);
1945         scsi_host_put(shost);
1946         module_put(owner);
1947 }
1948 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1949
1950 /**
1951  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1952  * @cls_session: iscsi_cls_session
1953  * @conn_idx: cid
1954  **/
1955 struct iscsi_cls_conn *
1956 iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1957 {
1958         struct iscsi_session *session = class_to_transport_session(cls_session);
1959         struct iscsi_conn *conn;
1960         struct iscsi_cls_conn *cls_conn;
1961         char *data;
1962
1963         cls_conn = iscsi_create_conn(cls_session, conn_idx);
1964         if (!cls_conn)
1965                 return NULL;
1966         conn = cls_conn->dd_data;
1967         memset(conn, 0, sizeof(*conn));
1968
1969         conn->session = session;
1970         conn->cls_conn = cls_conn;
1971         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1972         conn->id = conn_idx;
1973         conn->exp_statsn = 0;
1974         conn->tmf_state = TMF_INITIAL;
1975
1976         init_timer(&conn->transport_timer);
1977         conn->transport_timer.data = (unsigned long)conn;
1978         conn->transport_timer.function = iscsi_check_transport_timeouts;
1979
1980         INIT_LIST_HEAD(&conn->run_list);
1981         INIT_LIST_HEAD(&conn->mgmt_run_list);
1982         INIT_LIST_HEAD(&conn->mgmtqueue);
1983         INIT_LIST_HEAD(&conn->xmitqueue);
1984         INIT_LIST_HEAD(&conn->requeue);
1985         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
1986
1987         /* allocate login_mtask used for the login/text sequences */
1988         spin_lock_bh(&session->lock);
1989         if (!__kfifo_get(session->mgmtpool.queue,
1990                          (void*)&conn->login_mtask,
1991                          sizeof(void*))) {
1992                 spin_unlock_bh(&session->lock);
1993                 goto login_mtask_alloc_fail;
1994         }
1995         spin_unlock_bh(&session->lock);
1996
1997         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
1998         if (!data)
1999                 goto login_mtask_data_alloc_fail;
2000         conn->login_mtask->data = conn->data = data;
2001
2002         init_timer(&conn->tmf_timer);
2003         init_waitqueue_head(&conn->ehwait);
2004
2005         return cls_conn;
2006
2007 login_mtask_data_alloc_fail:
2008         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2009                     sizeof(void*));
2010 login_mtask_alloc_fail:
2011         iscsi_destroy_conn(cls_conn);
2012         return NULL;
2013 }
2014 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2015
2016 /**
2017  * iscsi_conn_teardown - teardown iscsi connection
2018  * cls_conn: iscsi class connection
2019  *
2020  * TODO: we may need to make this into a two step process
2021  * like scsi-mls remove + put host
2022  */
2023 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2024 {
2025         struct iscsi_conn *conn = cls_conn->dd_data;
2026         struct iscsi_session *session = conn->session;
2027         unsigned long flags;
2028
2029         del_timer_sync(&conn->transport_timer);
2030
2031         spin_lock_bh(&session->lock);
2032         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2033         if (session->leadconn == conn) {
2034                 /*
2035                  * leading connection? then give up on recovery.
2036                  */
2037                 session->state = ISCSI_STATE_TERMINATE;
2038                 wake_up(&conn->ehwait);
2039         }
2040         spin_unlock_bh(&session->lock);
2041
2042         /*
2043          * Block until all in-progress commands for this connection
2044          * time out or fail.
2045          */
2046         for (;;) {
2047                 spin_lock_irqsave(session->host->host_lock, flags);
2048                 if (!session->host->host_busy) { /* OK for ERL == 0 */
2049                         spin_unlock_irqrestore(session->host->host_lock, flags);
2050                         break;
2051                 }
2052                 spin_unlock_irqrestore(session->host->host_lock, flags);
2053                 msleep_interruptible(500);
2054                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2055                                   "host_busy %d host_failed %d\n",
2056                                   session->host->host_busy,
2057                                   session->host->host_failed);
2058                 /*
2059                  * force eh_abort() to unblock
2060                  */
2061                 wake_up(&conn->ehwait);
2062         }
2063
2064         /* flush queued up work because we free the connection below */
2065         iscsi_suspend_tx(conn);
2066
2067         spin_lock_bh(&session->lock);
2068         kfree(conn->data);
2069         kfree(conn->persistent_address);
2070         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2071                     sizeof(void*));
2072         if (session->leadconn == conn)
2073                 session->leadconn = NULL;
2074         spin_unlock_bh(&session->lock);
2075
2076         iscsi_destroy_conn(cls_conn);
2077 }
2078 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2079
2080 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2081 {
2082         struct iscsi_conn *conn = cls_conn->dd_data;
2083         struct iscsi_session *session = conn->session;
2084
2085         if (!session) {
2086                 iscsi_conn_printk(KERN_ERR, conn,
2087                                   "can't start unbound connection\n");
2088                 return -EPERM;
2089         }
2090
2091         if ((session->imm_data_en || !session->initial_r2t_en) &&
2092              session->first_burst > session->max_burst) {
2093                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2094                                   "first_burst %d max_burst %d\n",
2095                                   session->first_burst, session->max_burst);
2096                 return -EINVAL;
2097         }
2098
2099         if (conn->ping_timeout && !conn->recv_timeout) {
2100                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2101                                   "zero. Using 5 seconds\n.");
2102                 conn->recv_timeout = 5;
2103         }
2104
2105         if (conn->recv_timeout && !conn->ping_timeout) {
2106                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2107                                   "zero. Using 5 seconds.\n");
2108                 conn->ping_timeout = 5;
2109         }
2110
2111         spin_lock_bh(&session->lock);
2112         conn->c_stage = ISCSI_CONN_STARTED;
2113         session->state = ISCSI_STATE_LOGGED_IN;
2114         session->queued_cmdsn = session->cmdsn;
2115
2116         conn->last_recv = jiffies;
2117         conn->last_ping = jiffies;
2118         if (conn->recv_timeout && conn->ping_timeout)
2119                 mod_timer(&conn->transport_timer,
2120                           jiffies + (conn->recv_timeout * HZ));
2121
2122         switch(conn->stop_stage) {
2123         case STOP_CONN_RECOVER:
2124                 /*
2125                  * unblock eh_abort() if it is blocked. re-try all
2126                  * commands after successful recovery
2127                  */
2128                 conn->stop_stage = 0;
2129                 conn->tmf_state = TMF_INITIAL;
2130                 session->age++;
2131                 if (session->age == 16)
2132                         session->age = 0;
2133                 break;
2134         case STOP_CONN_TERM:
2135                 conn->stop_stage = 0;
2136                 break;
2137         default:
2138                 break;
2139         }
2140         spin_unlock_bh(&session->lock);
2141
2142         iscsi_unblock_session(session_to_cls(session));
2143         wake_up(&conn->ehwait);
2144         return 0;
2145 }
2146 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2147
2148 static void
2149 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2150 {
2151         struct iscsi_mgmt_task *mtask, *tmp;
2152
2153         /* handle pending */
2154         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2155                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2156                 iscsi_free_mgmt_task(conn, mtask);
2157         }
2158
2159         /* handle running */
2160         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2161                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2162                 iscsi_free_mgmt_task(conn, mtask);
2163         }
2164
2165         conn->mtask = NULL;
2166 }
2167
2168 static void iscsi_start_session_recovery(struct iscsi_session *session,
2169                                          struct iscsi_conn *conn, int flag)
2170 {
2171         int old_stop_stage;
2172
2173         del_timer_sync(&conn->transport_timer);
2174
2175         mutex_lock(&session->eh_mutex);
2176         spin_lock_bh(&session->lock);
2177         if (conn->stop_stage == STOP_CONN_TERM) {
2178                 spin_unlock_bh(&session->lock);
2179                 mutex_unlock(&session->eh_mutex);
2180                 return;
2181         }
2182
2183         /*
2184          * The LLD either freed/unset the lock on us, or userspace called
2185          * stop but did not create a proper connection (connection was never
2186          * bound or it was unbound then stop was called).
2187          */
2188         if (!conn->recv_lock) {
2189                 spin_unlock_bh(&session->lock);
2190                 mutex_unlock(&session->eh_mutex);
2191                 return;
2192         }
2193
2194         /*
2195          * When this is called for the in_login state, we only want to clean
2196          * up the login task and connection. We do not need to block and set
2197          * the recovery state again
2198          */
2199         if (flag == STOP_CONN_TERM)
2200                 session->state = ISCSI_STATE_TERMINATE;
2201         else if (conn->stop_stage != STOP_CONN_RECOVER)
2202                 session->state = ISCSI_STATE_IN_RECOVERY;
2203
2204         old_stop_stage = conn->stop_stage;
2205         conn->stop_stage = flag;
2206         conn->c_stage = ISCSI_CONN_STOPPED;
2207         spin_unlock_bh(&session->lock);
2208
2209         iscsi_suspend_tx(conn);
2210
2211         write_lock_bh(conn->recv_lock);
2212         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2213         write_unlock_bh(conn->recv_lock);
2214
2215         /*
2216          * for connection level recovery we should not calculate
2217          * header digest. conn->hdr_size used for optimization
2218          * in hdr_extract() and will be re-negotiated at
2219          * set_param() time.
2220          */
2221         if (flag == STOP_CONN_RECOVER) {
2222                 conn->hdrdgst_en = 0;
2223                 conn->datadgst_en = 0;
2224                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2225                     old_stop_stage != STOP_CONN_RECOVER) {
2226                         debug_scsi("blocking session\n");
2227                         iscsi_block_session(session_to_cls(session));
2228                 }
2229         }
2230
2231         /*
2232          * flush queues.
2233          */
2234         spin_lock_bh(&session->lock);
2235         fail_all_commands(conn, -1,
2236                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2237         flush_control_queues(session, conn);
2238         spin_unlock_bh(&session->lock);
2239         mutex_unlock(&session->eh_mutex);
2240 }
2241
2242 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2243 {
2244         struct iscsi_conn *conn = cls_conn->dd_data;
2245         struct iscsi_session *session = conn->session;
2246
2247         switch (flag) {
2248         case STOP_CONN_RECOVER:
2249         case STOP_CONN_TERM:
2250                 iscsi_start_session_recovery(session, conn, flag);
2251                 break;
2252         default:
2253                 iscsi_conn_printk(KERN_ERR, conn,
2254                                   "invalid stop flag %d\n", flag);
2255         }
2256 }
2257 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2258
2259 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2260                     struct iscsi_cls_conn *cls_conn, int is_leading)
2261 {
2262         struct iscsi_session *session = class_to_transport_session(cls_session);
2263         struct iscsi_conn *conn = cls_conn->dd_data;
2264
2265         spin_lock_bh(&session->lock);
2266         if (is_leading)
2267                 session->leadconn = conn;
2268         spin_unlock_bh(&session->lock);
2269
2270         /*
2271          * Unblock xmitworker(), Login Phase will pass through.
2272          */
2273         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2274         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2275         return 0;
2276 }
2277 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2278
2279
2280 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2281                     enum iscsi_param param, char *buf, int buflen)
2282 {
2283         struct iscsi_conn *conn = cls_conn->dd_data;
2284         struct iscsi_session *session = conn->session;
2285         uint32_t value;
2286
2287         switch(param) {
2288         case ISCSI_PARAM_FAST_ABORT:
2289                 sscanf(buf, "%d", &session->fast_abort);
2290                 break;
2291         case ISCSI_PARAM_ABORT_TMO:
2292                 sscanf(buf, "%d", &session->abort_timeout);
2293                 break;
2294         case ISCSI_PARAM_LU_RESET_TMO:
2295                 sscanf(buf, "%d", &session->lu_reset_timeout);
2296                 break;
2297         case ISCSI_PARAM_PING_TMO:
2298                 sscanf(buf, "%d", &conn->ping_timeout);
2299                 break;
2300         case ISCSI_PARAM_RECV_TMO:
2301                 sscanf(buf, "%d", &conn->recv_timeout);
2302                 break;
2303         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2304                 sscanf(buf, "%d", &conn->max_recv_dlength);
2305                 break;
2306         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2307                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2308                 break;
2309         case ISCSI_PARAM_HDRDGST_EN:
2310                 sscanf(buf, "%d", &conn->hdrdgst_en);
2311                 break;
2312         case ISCSI_PARAM_DATADGST_EN:
2313                 sscanf(buf, "%d", &conn->datadgst_en);
2314                 break;
2315         case ISCSI_PARAM_INITIAL_R2T_EN:
2316                 sscanf(buf, "%d", &session->initial_r2t_en);
2317                 break;
2318         case ISCSI_PARAM_MAX_R2T:
2319                 sscanf(buf, "%d", &session->max_r2t);
2320                 break;
2321         case ISCSI_PARAM_IMM_DATA_EN:
2322                 sscanf(buf, "%d", &session->imm_data_en);
2323                 break;
2324         case ISCSI_PARAM_FIRST_BURST:
2325                 sscanf(buf, "%d", &session->first_burst);
2326                 break;
2327         case ISCSI_PARAM_MAX_BURST:
2328                 sscanf(buf, "%d", &session->max_burst);
2329                 break;
2330         case ISCSI_PARAM_PDU_INORDER_EN:
2331                 sscanf(buf, "%d", &session->pdu_inorder_en);
2332                 break;
2333         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2334                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2335                 break;
2336         case ISCSI_PARAM_ERL:
2337                 sscanf(buf, "%d", &session->erl);
2338                 break;
2339         case ISCSI_PARAM_IFMARKER_EN:
2340                 sscanf(buf, "%d", &value);
2341                 BUG_ON(value);
2342                 break;
2343         case ISCSI_PARAM_OFMARKER_EN:
2344                 sscanf(buf, "%d", &value);
2345                 BUG_ON(value);
2346                 break;
2347         case ISCSI_PARAM_EXP_STATSN:
2348                 sscanf(buf, "%u", &conn->exp_statsn);
2349                 break;
2350         case ISCSI_PARAM_USERNAME:
2351                 kfree(session->username);
2352                 session->username = kstrdup(buf, GFP_KERNEL);
2353                 if (!session->username)
2354                         return -ENOMEM;
2355                 break;
2356         case ISCSI_PARAM_USERNAME_IN:
2357                 kfree(session->username_in);
2358                 session->username_in = kstrdup(buf, GFP_KERNEL);
2359                 if (!session->username_in)
2360                         return -ENOMEM;
2361                 break;
2362         case ISCSI_PARAM_PASSWORD:
2363                 kfree(session->password);
2364                 session->password = kstrdup(buf, GFP_KERNEL);
2365                 if (!session->password)
2366                         return -ENOMEM;
2367                 break;
2368         case ISCSI_PARAM_PASSWORD_IN:
2369                 kfree(session->password_in);
2370                 session->password_in = kstrdup(buf, GFP_KERNEL);
2371                 if (!session->password_in)
2372                         return -ENOMEM;
2373                 break;
2374         case ISCSI_PARAM_TARGET_NAME:
2375                 /* this should not change between logins */
2376                 if (session->targetname)
2377                         break;
2378
2379                 session->targetname = kstrdup(buf, GFP_KERNEL);
2380                 if (!session->targetname)
2381                         return -ENOMEM;
2382                 break;
2383         case ISCSI_PARAM_TPGT:
2384                 sscanf(buf, "%d", &session->tpgt);
2385                 break;
2386         case ISCSI_PARAM_PERSISTENT_PORT:
2387                 sscanf(buf, "%d", &conn->persistent_port);
2388                 break;
2389         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2390                 /*
2391                  * this is the address returned in discovery so it should
2392                  * not change between logins.
2393                  */
2394                 if (conn->persistent_address)
2395                         break;
2396
2397                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2398                 if (!conn->persistent_address)
2399                         return -ENOMEM;
2400                 break;
2401         default:
2402                 return -ENOSYS;
2403         }
2404
2405         return 0;
2406 }
2407 EXPORT_SYMBOL_GPL(iscsi_set_param);
2408
2409 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2410                             enum iscsi_param param, char *buf)
2411 {
2412         struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
2413         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2414         int len;
2415
2416         switch(param) {
2417         case ISCSI_PARAM_FAST_ABORT:
2418                 len = sprintf(buf, "%d\n", session->fast_abort);
2419                 break;
2420         case ISCSI_PARAM_ABORT_TMO:
2421                 len = sprintf(buf, "%d\n", session->abort_timeout);
2422                 break;
2423         case ISCSI_PARAM_LU_RESET_TMO:
2424                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2425                 break;
2426         case ISCSI_PARAM_INITIAL_R2T_EN:
2427                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2428                 break;
2429         case ISCSI_PARAM_MAX_R2T:
2430                 len = sprintf(buf, "%hu\n", session->max_r2t);
2431                 break;
2432         case ISCSI_PARAM_IMM_DATA_EN:
2433                 len = sprintf(buf, "%d\n", session->imm_data_en);
2434                 break;
2435         case ISCSI_PARAM_FIRST_BURST:
2436                 len = sprintf(buf, "%u\n", session->first_burst);
2437                 break;
2438         case ISCSI_PARAM_MAX_BURST:
2439                 len = sprintf(buf, "%u\n", session->max_burst);
2440                 break;
2441         case ISCSI_PARAM_PDU_INORDER_EN:
2442                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2443                 break;
2444         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2445                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2446                 break;
2447         case ISCSI_PARAM_ERL:
2448                 len = sprintf(buf, "%d\n", session->erl);
2449                 break;
2450         case ISCSI_PARAM_TARGET_NAME:
2451                 len = sprintf(buf, "%s\n", session->targetname);
2452                 break;
2453         case ISCSI_PARAM_TPGT:
2454                 len = sprintf(buf, "%d\n", session->tpgt);
2455                 break;
2456         case ISCSI_PARAM_USERNAME:
2457                 len = sprintf(buf, "%s\n", session->username);
2458                 break;
2459         case ISCSI_PARAM_USERNAME_IN:
2460                 len = sprintf(buf, "%s\n", session->username_in);
2461                 break;
2462         case ISCSI_PARAM_PASSWORD:
2463                 len = sprintf(buf, "%s\n", session->password);
2464                 break;
2465         case ISCSI_PARAM_PASSWORD_IN:
2466                 len = sprintf(buf, "%s\n", session->password_in);
2467                 break;
2468         default:
2469                 return -ENOSYS;
2470         }
2471
2472         return len;
2473 }
2474 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2475
2476 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2477                          enum iscsi_param param, char *buf)
2478 {
2479         struct iscsi_conn *conn = cls_conn->dd_data;
2480         int len;
2481
2482         switch(param) {
2483         case ISCSI_PARAM_PING_TMO:
2484                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2485                 break;
2486         case ISCSI_PARAM_RECV_TMO:
2487                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2488                 break;
2489         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2490                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2491                 break;
2492         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2493                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2494                 break;
2495         case ISCSI_PARAM_HDRDGST_EN:
2496                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2497                 break;
2498         case ISCSI_PARAM_DATADGST_EN:
2499                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2500                 break;
2501         case ISCSI_PARAM_IFMARKER_EN:
2502                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2503                 break;
2504         case ISCSI_PARAM_OFMARKER_EN:
2505                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2506                 break;
2507         case ISCSI_PARAM_EXP_STATSN:
2508                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2509                 break;
2510         case ISCSI_PARAM_PERSISTENT_PORT:
2511                 len = sprintf(buf, "%d\n", conn->persistent_port);
2512                 break;
2513         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2514                 len = sprintf(buf, "%s\n", conn->persistent_address);
2515                 break;
2516         default:
2517                 return -ENOSYS;
2518         }
2519
2520         return len;
2521 }
2522 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2523
2524 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2525                          char *buf)
2526 {
2527         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2528         int len;
2529
2530         switch (param) {
2531         case ISCSI_HOST_PARAM_NETDEV_NAME:
2532                 if (!session->netdev)
2533                         len = sprintf(buf, "%s\n", "default");
2534                 else
2535                         len = sprintf(buf, "%s\n", session->netdev);
2536                 break;
2537         case ISCSI_HOST_PARAM_HWADDRESS:
2538                 if (!session->hwaddress)
2539                         len = sprintf(buf, "%s\n", "default");
2540                 else
2541                         len = sprintf(buf, "%s\n", session->hwaddress);
2542                 break;
2543         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2544                 if (!session->initiatorname)
2545                         len = sprintf(buf, "%s\n", "unknown");
2546                 else
2547                         len = sprintf(buf, "%s\n", session->initiatorname);
2548                 break;
2549
2550         default:
2551                 return -ENOSYS;
2552         }
2553
2554         return len;
2555 }
2556 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2557
2558 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2559                          char *buf, int buflen)
2560 {
2561         struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
2562
2563         switch (param) {
2564         case ISCSI_HOST_PARAM_NETDEV_NAME:
2565                 if (!session->netdev)
2566                         session->netdev = kstrdup(buf, GFP_KERNEL);
2567                 break;
2568         case ISCSI_HOST_PARAM_HWADDRESS:
2569                 if (!session->hwaddress)
2570                         session->hwaddress = kstrdup(buf, GFP_KERNEL);
2571                 break;
2572         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2573                 if (!session->initiatorname)
2574                         session->initiatorname = kstrdup(buf, GFP_KERNEL);
2575                 break;
2576         default:
2577                 return -ENOSYS;
2578         }
2579
2580         return 0;
2581 }
2582 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2583
2584 MODULE_AUTHOR("Mike Christie");
2585 MODULE_DESCRIPTION("iSCSI library functions");
2586 MODULE_LICENSE("GPL");