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 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  42 #define SNA32_CHECK 2147483648UL
  43
  44 static int iscsi_sna_lt(u32 n1, u32 n2)
  45 {
  46         return n1 != n2 && ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  47                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  48 }
  49
  50 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
  51 static int iscsi_sna_lte(u32 n1, u32 n2)
  52 {
  53         return n1 == n2 || ((n1 < n2 && (n2 - n1 < SNA32_CHECK)) ||
  54                             (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
  55 }
  56
  57 void
  58 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
  59 {
  60         uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
  61         uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
  62
  63         /*
  64          * standard specifies this check for when to update expected and
  65          * max sequence numbers
  66          */
  67         if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
  68                 return;
  69
  70         if (exp_cmdsn != session->exp_cmdsn &&
  71             !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
  72                 session->exp_cmdsn = exp_cmdsn;
  73
  74         if (max_cmdsn != session->max_cmdsn &&
  75             !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
  76                 session->max_cmdsn = max_cmdsn;
  77                 /*
  78                  * if the window closed with IO queued, then kick the
  79                  * xmit thread
  80                  */
  81                 if (!list_empty(&session->leadconn->xmitqueue) ||
  82                     !list_empty(&session->leadconn->mgmtqueue))
  83                         scsi_queue_work(session->host,
  84                                         &session->leadconn->xmitwork);
  85         }
  86 }
  87 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
  88
  89 void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
  90                                    struct iscsi_data *hdr)
  91 {
  92         struct iscsi_conn *conn = ctask->conn;
  93
  94         memset(hdr, 0, sizeof(struct iscsi_data));
  95         hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
  96         hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
  97         ctask->unsol_datasn++;
  98         hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
  99         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
 100
 101         hdr->itt = ctask->hdr->itt;
 102         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 103         hdr->offset = cpu_to_be32(ctask->unsol_offset);
 104
 105         if (ctask->unsol_count > conn->max_xmit_dlength) {
 106                 hton24(hdr->dlength, conn->max_xmit_dlength);
 107                 ctask->data_count = conn->max_xmit_dlength;
 108                 ctask->unsol_offset += ctask->data_count;
 109                 hdr->flags = 0;
 110         } else {
 111                 hton24(hdr->dlength, ctask->unsol_count);
 112                 ctask->data_count = ctask->unsol_count;
 113                 hdr->flags = ISCSI_FLAG_CMD_FINAL;
 114         }
 115 }
 116 EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
 117
 118 static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
 119 {
 120         unsigned exp_len = ctask->hdr_len + len;
 121
 122         if (exp_len > ctask->hdr_max) {
 123                 WARN_ON(1);
 124                 return -EINVAL;
 125         }
 126
 127         WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 128         ctask->hdr_len = exp_len;
 129         return 0;
 130 }
 131
 132 /*
 133  * make an extended cdb AHS
 134  */
 135 static int iscsi_prep_ecdb_ahs(struct iscsi_cmd_task *ctask)
 136 {
 137         struct scsi_cmnd *cmd = ctask->sc;
 138         unsigned rlen, pad_len;
 139         unsigned short ahslength;
 140         struct iscsi_ecdb_ahdr *ecdb_ahdr;
 141         int rc;
 142
 143         ecdb_ahdr = iscsi_next_hdr(ctask);
 144         rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
 145
 146         BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
 147         ahslength = rlen + sizeof(ecdb_ahdr->reserved);
 148
 149         pad_len = iscsi_padding(rlen);
 150
 151         rc = iscsi_add_hdr(ctask, sizeof(ecdb_ahdr->ahslength) +
 152                            sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
 153         if (rc)
 154                 return rc;
 155
 156         if (pad_len)
 157                 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
 158
 159         ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
 160         ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
 161         ecdb_ahdr->reserved = 0;
 162         memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
 163
 164         debug_scsi("iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
 165                    "rlen %d pad_len %d ahs_length %d iscsi_headers_size %u\n",
 166                    cmd->cmd_len, rlen, pad_len, ahslength, ctask->hdr_len);
 167
 168         return 0;
 169 }
 170
 171 static int iscsi_prep_bidi_ahs(struct iscsi_cmd_task *ctask)
 172 {
 173         struct scsi_cmnd *sc = ctask->sc;
 174         struct iscsi_rlength_ahdr *rlen_ahdr;
 175         int rc;
 176
 177         rlen_ahdr = iscsi_next_hdr(ctask);
 178         rc = iscsi_add_hdr(ctask, sizeof(*rlen_ahdr));
 179         if (rc)
 180                 return rc;
 181
 182         rlen_ahdr->ahslength =
 183                 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
 184                                                   sizeof(rlen_ahdr->reserved));
 185         rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
 186         rlen_ahdr->reserved = 0;
 187         rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
 188
 189         debug_scsi("bidi-in rlen_ahdr->read_length(%d) "
 190                    "rlen_ahdr->ahslength(%d)\n",
 191                    be32_to_cpu(rlen_ahdr->read_length),
 192                    be16_to_cpu(rlen_ahdr->ahslength));
 193         return 0;
 194 }
 195
 196 /**
 197  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 198  * @ctask: iscsi cmd task
 199  *
 200  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 201  * fields like dlength or final based on how much data it sends
 202  */
 203 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
 204 {
 205         struct iscsi_conn *conn = ctask->conn;
 206         struct iscsi_session *session = conn->session;
 207         struct iscsi_cmd *hdr = ctask->hdr;
 208         struct scsi_cmnd *sc = ctask->sc;
 209         unsigned hdrlength, cmd_len;
 210         int rc;
 211
 212         ctask->hdr_len = 0;
 213         rc = iscsi_add_hdr(ctask, sizeof(*hdr));
 214         if (rc)
 215                 return rc;
 216         hdr->opcode = ISCSI_OP_SCSI_CMD;
 217         hdr->flags = ISCSI_ATTR_SIMPLE;
 218         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
 219         hdr->itt = build_itt(ctask->itt, session->age);
 220         hdr->cmdsn = cpu_to_be32(session->cmdsn);
 221         session->cmdsn++;
 222         hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 223         cmd_len = sc->cmd_len;
 224         if (cmd_len < ISCSI_CDB_SIZE)
 225                 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
 226         else if (cmd_len > ISCSI_CDB_SIZE) {
 227                 rc = iscsi_prep_ecdb_ahs(ctask);
 228                 if (rc)
 229                         return rc;
 230                 cmd_len = ISCSI_CDB_SIZE;
 231         }
 232         memcpy(hdr->cdb, sc->cmnd, cmd_len);
 233
 234         ctask->imm_count = 0;
 235         if (scsi_bidi_cmnd(sc)) {
 236                 hdr->flags |= ISCSI_FLAG_CMD_READ;
 237                 rc = iscsi_prep_bidi_ahs(ctask);
 238                 if (rc)
 239                         return rc;
 240         }
 241         if (sc->sc_data_direction == DMA_TO_DEVICE) {
 242                 unsigned out_len = scsi_out(sc)->length;
 243                 hdr->data_length = cpu_to_be32(out_len);
 244                 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 245                 /*
 246                  * Write counters:
 247                  *
 248                  *      imm_count       bytes to be sent right after
 249                  *                      SCSI PDU Header
 250                  *
 251                  *      unsol_count     bytes(as Data-Out) to be sent
 252                  *                      without R2T ack right after
 253                  *                      immediate data
 254                  *
 255                  *      r2t_data_count  bytes to be sent via R2T ack's
 256                  *
 257                  *      pad_count       bytes to be sent as zero-padding
 258                  */
 259                 ctask->unsol_count = 0;
 260                 ctask->unsol_offset = 0;
 261                 ctask->unsol_datasn = 0;
 262
 263                 if (session->imm_data_en) {
 264                         if (out_len >= session->first_burst)
 265                                 ctask->imm_count = min(session->first_burst,
 266                                                         conn->max_xmit_dlength);
 267                         else
 268                                 ctask->imm_count = min(out_len,
 269                                                         conn->max_xmit_dlength);
 270                         hton24(hdr->dlength, ctask->imm_count);
 271                 } else
 272                         zero_data(hdr->dlength);
 273
 274                 if (!session->initial_r2t_en) {
 275                         ctask->unsol_count = min(session->first_burst, out_len)
 276                                                              - ctask->imm_count;
 277                         ctask->unsol_offset = ctask->imm_count;
 278                 }
 279
 280                 if (!ctask->unsol_count)
 281                         /* No unsolicit Data-Out's */
 282                         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 283         } else {
 284                 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 285                 zero_data(hdr->dlength);
 286                 hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
 287
 288                 if (sc->sc_data_direction == DMA_FROM_DEVICE)
 289                         hdr->flags |= ISCSI_FLAG_CMD_READ;
 290         }
 291
 292         /* calculate size of additional header segments (AHSs) */
 293         hdrlength = ctask->hdr_len - sizeof(*hdr);
 294
 295         WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 296         hdrlength /= ISCSI_PAD_LEN;
 297
 298         WARN_ON(hdrlength >= 256);
 299         hdr->hlength = hdrlength & 0xFF;
 300
 301         if (conn->session->tt->init_cmd_task(conn->ctask))
 302                 return EIO;
 303
 304         conn->scsicmd_pdus_cnt++;
 305         debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x "
 306                 "len %d bidi_len %d cmdsn %d win %d]\n",
 307                 scsi_bidi_cmnd(sc) ? "bidirectional" :
 308                      sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
 309                 conn->id, sc, sc->cmnd[0], ctask->itt,
 310                 scsi_bufflen(sc), scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
 311                 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
 312         return 0;
 313 }
 314
 315 /**
 316  * iscsi_complete_command - return command back to scsi-ml
 317  * @ctask: iscsi cmd task
 318  *
 319  * Must be called with session lock.
 320  * This function returns the scsi command to scsi-ml and returns
 321  * the cmd task to the pool of available cmd tasks.
 322  */
 323 static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
 324 {
 325         struct iscsi_conn *conn = ctask->conn;
 326         struct iscsi_session *session = conn->session;
 327         struct scsi_cmnd *sc = ctask->sc;
 328
 329         ctask->state = ISCSI_TASK_COMPLETED;
 330         ctask->sc = NULL;
 331         /* SCSI eh reuses commands to verify us */
 332         sc->SCp.ptr = NULL;
 333         if (conn->ctask == ctask)
 334                 conn->ctask = NULL;
 335         list_del_init(&ctask->running);
 336         __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
 337         sc->scsi_done(sc);
 338 }
 339
 340 static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
 341 {
 342         atomic_inc(&ctask->refcount);
 343 }
 344
 345 static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
 346 {
 347         if (atomic_dec_and_test(&ctask->refcount))
 348                 iscsi_complete_command(ctask);
 349 }
 350
 351 /*
 352  * session lock must be held
 353  */
 354 static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
 355                          int err)
 356 {
 357         struct scsi_cmnd *sc;
 358
 359         sc = ctask->sc;
 360         if (!sc)
 361                 return;
 362
 363         if (ctask->state == ISCSI_TASK_PENDING)
 364                 /*
 365                  * cmd never made it to the xmit thread, so we should not count
 366                  * the cmd in the sequencing
 367                  */
 368                 conn->session->queued_cmdsn--;
 369         else
 370                 conn->session->tt->cleanup_cmd_task(conn, ctask);
 371
 372         sc->result = err;
 373         if (!scsi_bidi_cmnd(sc))
 374                 scsi_set_resid(sc, scsi_bufflen(sc));
 375         else {
 376                 scsi_out(sc)->resid = scsi_out(sc)->length;
 377                 scsi_in(sc)->resid = scsi_in(sc)->length;
 378         }
 379         if (conn->ctask == ctask)
 380                 conn->ctask = NULL;
 381         /* release ref from queuecommand */
 382         __iscsi_put_ctask(ctask);
 383 }
 384
 385 /**
 386  * iscsi_free_mgmt_task - return mgmt task back to pool
 387  * @conn: iscsi connection
 388  * @mtask: mtask
 389  *
 390  * Must be called with session lock.
 391  */
 392 void iscsi_free_mgmt_task(struct iscsi_conn *conn,
 393                           struct iscsi_mgmt_task *mtask)
 394 {
 395         list_del_init(&mtask->running);
 396         if (conn->login_mtask == mtask)
 397                 return;
 398
 399         if (conn->ping_mtask == mtask)
 400                 conn->ping_mtask = NULL;
 401         __kfifo_put(conn->session->mgmtpool.queue,
 402                     (void*)&mtask, sizeof(void*));
 403 }
 404 EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
 405
 406 static struct iscsi_mgmt_task *
 407 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 408                       char *data, uint32_t data_size)
 409 {
 410         struct iscsi_session *session = conn->session;
 411         struct iscsi_mgmt_task *mtask;
 412
 413         if (session->state == ISCSI_STATE_TERMINATE)
 414                 return NULL;
 415
 416         if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
 417             hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 418                 /*
 419                  * Login and Text are sent serially, in
 420                  * request-followed-by-response sequence.
 421                  * Same mtask can be used. Same ITT must be used.
 422                  * Note that login_mtask is preallocated at conn_create().
 423                  */
 424                 mtask = conn->login_mtask;
 425         else {
 426                 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 427                 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 428
 429                 if (!__kfifo_get(session->mgmtpool.queue,
 430                                  (void*)&mtask, sizeof(void*)))
 431                         return NULL;
 432         }
 433
 434         if (data_size) {
 435                 memcpy(mtask->data, data, data_size);
 436                 mtask->data_count = data_size;
 437         } else
 438                 mtask->data_count = 0;
 439
 440         memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
 441         INIT_LIST_HEAD(&mtask->running);
 442         list_add_tail(&mtask->running, &conn->mgmtqueue);
 443         return mtask;
 444 }
 445
 446 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 447                         char *data, uint32_t data_size)
 448 {
 449         struct iscsi_conn *conn = cls_conn->dd_data;
 450         struct iscsi_session *session = conn->session;
 451         int err = 0;
 452
 453         spin_lock_bh(&session->lock);
 454         if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 455                 err = -EPERM;
 456         spin_unlock_bh(&session->lock);
 457         scsi_queue_work(session->host, &conn->xmitwork);
 458         return err;
 459 }
 460 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 461
 462 /**
 463  * iscsi_cmd_rsp - SCSI Command Response processing
 464  * @conn: iscsi connection
 465  * @hdr: iscsi header
 466  * @ctask: scsi command task
 467  * @data: cmd data buffer
 468  * @datalen: len of buffer
 469  *
 470  * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 471  * then completes the command and task.
 472  **/
 473 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 474                                struct iscsi_cmd_task *ctask, char *data,
 475                                int datalen)
 476 {
 477         struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
 478         struct iscsi_session *session = conn->session;
 479         struct scsi_cmnd *sc = ctask->sc;
 480
 481         iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 482         conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 483
 484         sc->result = (DID_OK << 16) | rhdr->cmd_status;
 485
 486         if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 487                 sc->result = DID_ERROR << 16;
 488                 goto out;
 489         }
 490
 491         if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 492                 uint16_t senselen;
 493
 494                 if (datalen < 2) {
 495 invalid_datalen:
 496                         iscsi_conn_printk(KERN_ERR,  conn,
 497                                          "Got CHECK_CONDITION but invalid data "
 498                                          "buffer size of %d\n", datalen);
 499                         sc->result = DID_BAD_TARGET << 16;
 500                         goto out;
 501                 }
 502
 503                 senselen = be16_to_cpu(get_unaligned((__be16 *) data));
 504                 if (datalen < senselen)
 505                         goto invalid_datalen;
 506
 507                 memcpy(sc->sense_buffer, data + 2,
 508                        min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 509                 debug_scsi("copied %d bytes of sense\n",
 510                            min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 511         }
 512
 513         if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 514                            ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
 515                 int res_count = be32_to_cpu(rhdr->bi_residual_count);
 516
 517                 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
 518                                 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
 519                                  res_count <= scsi_in(sc)->length))
 520                         scsi_in(sc)->resid = res_count;
 521                 else
 522                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 523         }
 524
 525         if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 526                            ISCSI_FLAG_CMD_OVERFLOW)) {
 527                 int res_count = be32_to_cpu(rhdr->residual_count);
 528
 529                 if (res_count > 0 &&
 530                     (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 531                      res_count <= scsi_bufflen(sc)))
 532                         /* write side for bidi or uni-io set_resid */
 533                         scsi_set_resid(sc, res_count);
 534                 else
 535                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 536         }
 537 out:
 538         debug_scsi("done [sc %lx res %d itt 0x%x]\n",
 539                    (long)sc, sc->result, ctask->itt);
 540         conn->scsirsp_pdus_cnt++;
 541
 542         __iscsi_put_ctask(ctask);
 543 }
 544
 545 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 546 {
 547         struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 548
 549         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 550         conn->tmfrsp_pdus_cnt++;
 551
 552         if (conn->tmf_state != TMF_QUEUED)
 553                 return;
 554
 555         if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 556                 conn->tmf_state = TMF_SUCCESS;
 557         else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 558                 conn->tmf_state = TMF_NOT_FOUND;
 559         else
 560                 conn->tmf_state = TMF_FAILED;
 561         wake_up(&conn->ehwait);
 562 }
 563
 564 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 565 {
 566         struct iscsi_nopout hdr;
 567         struct iscsi_mgmt_task *mtask;
 568
 569         if (!rhdr && conn->ping_mtask)
 570                 return;
 571
 572         memset(&hdr, 0, sizeof(struct iscsi_nopout));
 573         hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 574         hdr.flags = ISCSI_FLAG_CMD_FINAL;
 575
 576         if (rhdr) {
 577                 memcpy(hdr.lun, rhdr->lun, 8);
 578                 hdr.ttt = rhdr->ttt;
 579                 hdr.itt = RESERVED_ITT;
 580         } else
 581                 hdr.ttt = RESERVED_ITT;
 582
 583         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 584         if (!mtask) {
 585                 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 586                 return;
 587         }
 588
 589         /* only track our nops */
 590         if (!rhdr) {
 591                 conn->ping_mtask = mtask;
 592                 conn->last_ping = jiffies;
 593         }
 594         scsi_queue_work(conn->session->host, &conn->xmitwork);
 595 }
 596
 597 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 598                                char *data, int datalen)
 599 {
 600         struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 601         struct iscsi_hdr rejected_pdu;
 602         uint32_t itt;
 603
 604         conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 605
 606         if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
 607                 if (ntoh24(reject->dlength) > datalen)
 608                         return ISCSI_ERR_PROTO;
 609
 610                 if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
 611                         memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
 612                         itt = get_itt(rejected_pdu.itt);
 613                         iscsi_conn_printk(KERN_ERR, conn,
 614                                           "itt 0x%x had pdu (op 0x%x) rejected "
 615                                           "due to DataDigest error.\n", itt,
 616                                           rejected_pdu.opcode);
 617                 }
 618         }
 619         return 0;
 620 }
 621
 622 /**
 623  * __iscsi_complete_pdu - complete pdu
 624  * @conn: iscsi conn
 625  * @hdr: iscsi header
 626  * @data: data buffer
 627  * @datalen: len of data buffer
 628  *
 629  * Completes pdu processing by freeing any resources allocated at
 630  * queuecommand or send generic. session lock must be held and verify
 631  * itt must have been called.
 632  */
 633 static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 634                                 char *data, int datalen)
 635 {
 636         struct iscsi_session *session = conn->session;
 637         int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
 638         struct iscsi_cmd_task *ctask;
 639         struct iscsi_mgmt_task *mtask;
 640         uint32_t itt;
 641
 642         conn->last_recv = jiffies;
 643         if (hdr->itt != RESERVED_ITT)
 644                 itt = get_itt(hdr->itt);
 645         else
 646                 itt = ~0U;
 647
 648         if (itt < session->cmds_max) {
 649                 ctask = session->cmds[itt];
 650
 651                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 652                            opcode, conn->id, ctask->itt, datalen);
 653
 654                 switch(opcode) {
 655                 case ISCSI_OP_SCSI_CMD_RSP:
 656                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 657                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 658                                            datalen);
 659                         break;
 660                 case ISCSI_OP_SCSI_DATA_IN:
 661                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 662                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 663                                 conn->scsirsp_pdus_cnt++;
 664                                 __iscsi_put_ctask(ctask);
 665                         }
 666                         break;
 667                 case ISCSI_OP_R2T:
 668                         /* LLD handles this for now */
 669                         break;
 670                 default:
 671                         rc = ISCSI_ERR_BAD_OPCODE;
 672                         break;
 673                 }
 674         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 675                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 676                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 677
 678                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 679                            opcode, conn->id, mtask->itt, datalen);
 680
 681                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 682                 switch(opcode) {
 683                 case ISCSI_OP_LOGOUT_RSP:
 684                         if (datalen) {
 685                                 rc = ISCSI_ERR_PROTO;
 686                                 break;
 687                         }
 688                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 689                         /* fall through */
 690                 case ISCSI_OP_LOGIN_RSP:
 691                 case ISCSI_OP_TEXT_RSP:
 692                         /*
 693                          * login related PDU's exp_statsn is handled in
 694                          * userspace
 695                          */
 696                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 697                                 rc = ISCSI_ERR_CONN_FAILED;
 698                         iscsi_free_mgmt_task(conn, mtask);
 699                         break;
 700                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 701                         if (datalen) {
 702                                 rc = ISCSI_ERR_PROTO;
 703                                 break;
 704                         }
 705
 706                         iscsi_tmf_rsp(conn, hdr);
 707                         iscsi_free_mgmt_task(conn, mtask);
 708                         break;
 709                 case ISCSI_OP_NOOP_IN:
 710                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 711                             datalen) {
 712                                 rc = ISCSI_ERR_PROTO;
 713                                 break;
 714                         }
 715                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 716
 717                         if (conn->ping_mtask != mtask) {
 718                                 /*
 719                                  * If this is not in response to one of our
 720                                  * nops then it must be from userspace.
 721                                  */
 722                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 723                                                    datalen))
 724                                         rc = ISCSI_ERR_CONN_FAILED;
 725                         } else
 726                                 mod_timer(&conn->transport_timer,
 727                                           jiffies + conn->recv_timeout);
 728                         iscsi_free_mgmt_task(conn, mtask);
 729                         break;
 730                 default:
 731                         rc = ISCSI_ERR_BAD_OPCODE;
 732                         break;
 733                 }
 734         } else if (itt == ~0U) {
 735                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 736
 737                 switch(opcode) {
 738                 case ISCSI_OP_NOOP_IN:
 739                         if (datalen) {
 740                                 rc = ISCSI_ERR_PROTO;
 741                                 break;
 742                         }
 743
 744                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 745                                 break;
 746
 747                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 748                         break;
 749                 case ISCSI_OP_REJECT:
 750                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 751                         break;
 752                 case ISCSI_OP_ASYNC_EVENT:
 753                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 754                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 755                                 rc = ISCSI_ERR_CONN_FAILED;
 756                         break;
 757                 default:
 758                         rc = ISCSI_ERR_BAD_OPCODE;
 759                         break;
 760                 }
 761         } else
 762                 rc = ISCSI_ERR_BAD_ITT;
 763
 764         return rc;
 765 }
 766
 767 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 768                        char *data, int datalen)
 769 {
 770         int rc;
 771
 772         spin_lock(&conn->session->lock);
 773         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 774         spin_unlock(&conn->session->lock);
 775         return rc;
 776 }
 777 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 778
 779 /* verify itt (itt encoding: age+cid+itt) */
 780 int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 781                      uint32_t *ret_itt)
 782 {
 783         struct iscsi_session *session = conn->session;
 784         struct iscsi_cmd_task *ctask;
 785         uint32_t itt;
 786
 787         if (hdr->itt != RESERVED_ITT) {
 788                 if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
 789                     (session->age << ISCSI_AGE_SHIFT)) {
 790                         iscsi_conn_printk(KERN_ERR, conn,
 791                                           "received itt %x expected session "
 792                                           "age (%x)\n", (__force u32)hdr->itt,
 793                                           session->age & ISCSI_AGE_MASK);
 794                         return ISCSI_ERR_BAD_ITT;
 795                 }
 796
 797                 itt = get_itt(hdr->itt);
 798         } else
 799                 itt = ~0U;
 800
 801         if (itt < session->cmds_max) {
 802                 ctask = session->cmds[itt];
 803
 804                 if (!ctask->sc) {
 805                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
 806                                           "with itt 0x%x\n", ctask->itt);
 807                         /* force drop */
 808                         return ISCSI_ERR_NO_SCSI_CMD;
 809                 }
 810
 811                 if (ctask->sc->SCp.phase != session->age) {
 812                         iscsi_conn_printk(KERN_ERR, conn,
 813                                           "iscsi: ctask's session age %d, "
 814                                           "expected %d\n", ctask->sc->SCp.phase,
 815                                           session->age);
 816                         return ISCSI_ERR_SESSION_FAILED;
 817                 }
 818         }
 819
 820         *ret_itt = itt;
 821         return 0;
 822 }
 823 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 824
 825 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 826 {
 827         struct iscsi_session *session = conn->session;
 828         unsigned long flags;
 829
 830         spin_lock_irqsave(&session->lock, flags);
 831         if (session->state == ISCSI_STATE_FAILED) {
 832                 spin_unlock_irqrestore(&session->lock, flags);
 833                 return;
 834         }
 835
 836         if (conn->stop_stage == 0)
 837                 session->state = ISCSI_STATE_FAILED;
 838         spin_unlock_irqrestore(&session->lock, flags);
 839         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 840         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 841         iscsi_conn_error(conn->cls_conn, err);
 842 }
 843 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 844
 845 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 846                              struct iscsi_mgmt_task *mtask)
 847 {
 848         struct iscsi_session *session = conn->session;
 849         struct iscsi_hdr *hdr = mtask->hdr;
 850         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 851
 852         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 853             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 854                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 855         /*
 856          * pre-format CmdSN for outgoing PDU.
 857          */
 858         nop->cmdsn = cpu_to_be32(session->cmdsn);
 859         if (hdr->itt != RESERVED_ITT) {
 860                 hdr->itt = build_itt(mtask->itt, session->age);
 861                 /*
 862                  * TODO: We always use immediate, so we never hit this.
 863                  * If we start to send tmfs or nops as non-immediate then
 864                  * we should start checking the cmdsn numbers for mgmt tasks.
 865                  */
 866                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 867                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 868                         session->queued_cmdsn++;
 869                         session->cmdsn++;
 870                 }
 871         }
 872
 873         if (session->tt->init_mgmt_task)
 874                 session->tt->init_mgmt_task(conn, mtask);
 875
 876         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 877                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 878                    mtask->data_count);
 879 }
 880
 881 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 882 {
 883         struct iscsi_hdr *hdr = conn->mtask->hdr;
 884         int rc;
 885
 886         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 887                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 888         spin_unlock_bh(&conn->session->lock);
 889
 890         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 891         spin_lock_bh(&conn->session->lock);
 892         if (rc)
 893                 return rc;
 894
 895         /* done with this in-progress mtask */
 896         conn->mtask = NULL;
 897         return 0;
 898 }
 899
 900 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 901 {
 902         struct iscsi_session *session = conn->session;
 903
 904         /*
 905          * Check for iSCSI window and take care of CmdSN wrap-around
 906          */
 907         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 908                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 909                            "CmdSN %u/%u\n", session->exp_cmdsn,
 910                            session->max_cmdsn, session->cmdsn,
 911                            session->queued_cmdsn);
 912                 return -ENOSPC;
 913         }
 914         return 0;
 915 }
 916
 917 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 918 {
 919         struct iscsi_cmd_task *ctask = conn->ctask;
 920         int rc;
 921
 922         __iscsi_get_ctask(ctask);
 923         spin_unlock_bh(&conn->session->lock);
 924         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 925         spin_lock_bh(&conn->session->lock);
 926         __iscsi_put_ctask(ctask);
 927         if (!rc)
 928                 /* done with this ctask */
 929                 conn->ctask = NULL;
 930         return rc;
 931 }
 932
 933 /**
 934  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 935  * @ctask: ctask to requeue
 936  *
 937  * LLDs that need to run a ctask from the session workqueue should call
 938  * this. The session lock must be held.
 939  */
 940 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 941 {
 942         struct iscsi_conn *conn = ctask->conn;
 943
 944         list_move_tail(&ctask->running, &conn->requeue);
 945         scsi_queue_work(conn->session->host, &conn->xmitwork);
 946 }
 947 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 948
 949 /**
 950  * iscsi_data_xmit - xmit any command into the scheduled connection
 951  * @conn: iscsi connection
 952  *
 953  * Notes:
 954  *      The function can return -EAGAIN in which case the caller must
 955  *      re-schedule it again later or recover. '0' return code means
 956  *      successful xmit.
 957  **/
 958 static int iscsi_data_xmit(struct iscsi_conn *conn)
 959 {
 960         int rc = 0;
 961
 962         spin_lock_bh(&conn->session->lock);
 963         if (unlikely(conn->suspend_tx)) {
 964                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 965                 spin_unlock_bh(&conn->session->lock);
 966                 return -ENODATA;
 967         }
 968
 969         if (conn->ctask) {
 970                 rc = iscsi_xmit_ctask(conn);
 971                 if (rc)
 972                         goto again;
 973         }
 974
 975         if (conn->mtask) {
 976                 rc = iscsi_xmit_mtask(conn);
 977                 if (rc)
 978                         goto again;
 979         }
 980
 981         /*
 982          * process mgmt pdus like nops before commands since we should
 983          * only have one nop-out as a ping from us and targets should not
 984          * overflow us with nop-ins
 985          */
 986 check_mgmt:
 987         while (!list_empty(&conn->mgmtqueue)) {
 988                 conn->mtask = list_entry(conn->mgmtqueue.next,
 989                                          struct iscsi_mgmt_task, running);
 990                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
 991                         iscsi_free_mgmt_task(conn, conn->mtask);
 992                         conn->mtask = NULL;
 993                         continue;
 994                 }
 995
 996                 iscsi_prep_mtask(conn, conn->mtask);
 997                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
 998                 rc = iscsi_xmit_mtask(conn);
 999                 if (rc)
1000                         goto again;
1001         }
1002
1003         /* process pending command queue */
1004         while (!list_empty(&conn->xmitqueue)) {
1005                 if (conn->tmf_state == TMF_QUEUED)
1006                         break;
1007
1008                 conn->ctask = list_entry(conn->xmitqueue.next,
1009                                          struct iscsi_cmd_task, running);
1010                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1011                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
1012                         continue;
1013                 }
1014                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
1015                         fail_command(conn, conn->ctask, DID_ABORT << 16);
1016                         continue;
1017                 }
1018
1019                 conn->ctask->state = ISCSI_TASK_RUNNING;
1020                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
1021                 rc = iscsi_xmit_ctask(conn);
1022                 if (rc)
1023                         goto again;
1024                 /*
1025                  * we could continuously get new ctask requests so
1026                  * we need to check the mgmt queue for nops that need to
1027                  * be sent to aviod starvation
1028                  */
1029                 if (!list_empty(&conn->mgmtqueue))
1030                         goto check_mgmt;
1031         }
1032
1033         while (!list_empty(&conn->requeue)) {
1034                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
1035                         break;
1036
1037                 /*
1038                  * we always do fastlogout - conn stop code will clean up.
1039                  */
1040                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1041                         break;
1042
1043                 conn->ctask = list_entry(conn->requeue.next,
1044                                          struct iscsi_cmd_task, running);
1045                 conn->ctask->state = ISCSI_TASK_RUNNING;
1046                 list_move_tail(conn->requeue.next, &conn->run_list);
1047                 rc = iscsi_xmit_ctask(conn);
1048                 if (rc)
1049                         goto again;
1050                 if (!list_empty(&conn->mgmtqueue))
1051                         goto check_mgmt;
1052         }
1053         spin_unlock_bh(&conn->session->lock);
1054         return -ENODATA;
1055
1056 again:
1057         if (unlikely(conn->suspend_tx))
1058                 rc = -ENODATA;
1059         spin_unlock_bh(&conn->session->lock);
1060         return rc;
1061 }
1062
1063 static void iscsi_xmitworker(struct work_struct *work)
1064 {
1065         struct iscsi_conn *conn =
1066                 container_of(work, struct iscsi_conn, xmitwork);
1067         int rc;
1068         /*
1069          * serialize Xmit worker on a per-connection basis.
1070          */
1071         do {
1072                 rc = iscsi_data_xmit(conn);
1073         } while (rc >= 0 || rc == -EAGAIN);
1074 }
1075
1076 enum {
1077         FAILURE_BAD_HOST = 1,
1078         FAILURE_SESSION_FAILED,
1079         FAILURE_SESSION_FREED,
1080         FAILURE_WINDOW_CLOSED,
1081         FAILURE_OOM,
1082         FAILURE_SESSION_TERMINATE,
1083         FAILURE_SESSION_IN_RECOVERY,
1084         FAILURE_SESSION_RECOVERY_TIMEOUT,
1085         FAILURE_SESSION_LOGGING_OUT,
1086         FAILURE_SESSION_NOT_READY,
1087 };
1088
1089 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1090 {
1091         struct iscsi_cls_session *cls_session;
1092         struct Scsi_Host *host;
1093         int reason = 0;
1094         struct iscsi_session *session;
1095         struct iscsi_conn *conn;
1096         struct iscsi_cmd_task *ctask = NULL;
1097
1098         sc->scsi_done = done;
1099         sc->result = 0;
1100         sc->SCp.ptr = NULL;
1101
1102         host = sc->device->host;
1103         spin_unlock(host->host_lock);
1104
1105         cls_session = starget_to_session(scsi_target(sc->device));
1106         session = cls_session->dd_data;
1107         spin_lock(&session->lock);
1108
1109         reason = iscsi_session_chkready(cls_session);
1110         if (reason) {
1111                 sc->result = reason;
1112                 goto fault;
1113         }
1114
1115         /*
1116          * ISCSI_STATE_FAILED is a temp. state. The recovery
1117          * code will decide what is best to do with command queued
1118          * during this time
1119          */
1120         if (session->state != ISCSI_STATE_LOGGED_IN &&
1121             session->state != ISCSI_STATE_FAILED) {
1122                 /*
1123                  * to handle the race between when we set the recovery state
1124                  * and block the session we requeue here (commands could
1125                  * be entering our queuecommand while a block is starting
1126                  * up because the block code is not locked)
1127                  */
1128                 switch (session->state) {
1129                 case ISCSI_STATE_IN_RECOVERY:
1130                         reason = FAILURE_SESSION_IN_RECOVERY;
1131                         sc->result = DID_IMM_RETRY << 16;
1132                         break;
1133                 case ISCSI_STATE_LOGGING_OUT:
1134                         reason = FAILURE_SESSION_LOGGING_OUT;
1135                         sc->result = DID_IMM_RETRY << 16;
1136                         break;
1137                 case ISCSI_STATE_RECOVERY_FAILED:
1138                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1139                         sc->result = DID_NO_CONNECT << 16;
1140                         break;
1141                 case ISCSI_STATE_TERMINATE:
1142                         reason = FAILURE_SESSION_TERMINATE;
1143                         sc->result = DID_NO_CONNECT << 16;
1144                         break;
1145                 default:
1146                         reason = FAILURE_SESSION_FREED;
1147                         sc->result = DID_NO_CONNECT << 16;
1148                 }
1149                 goto fault;
1150         }
1151
1152         conn = session->leadconn;
1153         if (!conn) {
1154                 reason = FAILURE_SESSION_FREED;
1155                 sc->result = DID_NO_CONNECT << 16;
1156                 goto fault;
1157         }
1158
1159         if (iscsi_check_cmdsn_window_closed(conn)) {
1160                 reason = FAILURE_WINDOW_CLOSED;
1161                 goto reject;
1162         }
1163
1164         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1165                          sizeof(void*))) {
1166                 reason = FAILURE_OOM;
1167                 goto reject;
1168         }
1169         session->queued_cmdsn++;
1170
1171         sc->SCp.phase = session->age;
1172         sc->SCp.ptr = (char *)ctask;
1173
1174         atomic_set(&ctask->refcount, 1);
1175         ctask->state = ISCSI_TASK_PENDING;
1176         ctask->conn = conn;
1177         ctask->sc = sc;
1178         INIT_LIST_HEAD(&ctask->running);
1179
1180         list_add_tail(&ctask->running, &conn->xmitqueue);
1181         spin_unlock(&session->lock);
1182
1183         scsi_queue_work(host, &conn->xmitwork);
1184         spin_lock(host->host_lock);
1185         return 0;
1186
1187 reject:
1188         spin_unlock(&session->lock);
1189         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1190         spin_lock(host->host_lock);
1191         return SCSI_MLQUEUE_HOST_BUSY;
1192
1193 fault:
1194         spin_unlock(&session->lock);
1195         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1196         if (!scsi_bidi_cmnd(sc))
1197                 scsi_set_resid(sc, scsi_bufflen(sc));
1198         else {
1199                 scsi_out(sc)->resid = scsi_out(sc)->length;
1200                 scsi_in(sc)->resid = scsi_in(sc)->length;
1201         }
1202         sc->scsi_done(sc);
1203         spin_lock(host->host_lock);
1204         return 0;
1205 }
1206 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1207
1208 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1209 {
1210         if (depth > ISCSI_MAX_CMD_PER_LUN)
1211                 depth = ISCSI_MAX_CMD_PER_LUN;
1212         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1213         return sdev->queue_depth;
1214 }
1215 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1216
1217 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1218 {
1219         struct iscsi_session *session = cls_session->dd_data;
1220
1221         spin_lock_bh(&session->lock);
1222         if (session->state != ISCSI_STATE_LOGGED_IN) {
1223                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1224                 if (session->leadconn)
1225                         wake_up(&session->leadconn->ehwait);
1226         }
1227         spin_unlock_bh(&session->lock);
1228 }
1229 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1230
1231 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1232 {
1233         struct iscsi_cls_session *cls_session;
1234         struct iscsi_session *session;
1235         struct iscsi_conn *conn;
1236
1237         cls_session = starget_to_session(scsi_target(sc->device));
1238         session = cls_session->dd_data;
1239         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 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 EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1392
1393 static void iscsi_start_tx(struct iscsi_conn *conn)
1394 {
1395         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1396         scsi_queue_work(conn->session->host, &conn->xmitwork);
1397 }
1398
1399 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1400 {
1401         struct iscsi_cls_session *cls_session;
1402         struct iscsi_session *session;
1403         struct iscsi_conn *conn;
1404         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1405
1406         cls_session = starget_to_session(scsi_target(scmd->device));
1407         session = cls_session->dd_data;
1408
1409         debug_scsi("scsi cmd %p timedout\n", scmd);
1410
1411         spin_lock(&session->lock);
1412         if (session->state != ISCSI_STATE_LOGGED_IN) {
1413                 /*
1414                  * We are probably in the middle of iscsi recovery so let
1415                  * that complete and handle the error.
1416                  */
1417                 rc = EH_RESET_TIMER;
1418                 goto done;
1419         }
1420
1421         conn = session->leadconn;
1422         if (!conn) {
1423                 /* In the middle of shuting down */
1424                 rc = EH_RESET_TIMER;
1425                 goto done;
1426         }
1427
1428         if (!conn->recv_timeout && !conn->ping_timeout)
1429                 goto done;
1430         /*
1431          * if the ping timedout then we are in the middle of cleaning up
1432          * and can let the iscsi eh handle it
1433          */
1434         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1435                             (conn->ping_timeout * HZ), jiffies))
1436                 rc = EH_RESET_TIMER;
1437         /*
1438          * if we are about to check the transport then give the command
1439          * more time
1440          */
1441         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1442                            jiffies))
1443                 rc = EH_RESET_TIMER;
1444         /* if in the middle of checking the transport then give us more time */
1445         if (conn->ping_mtask)
1446                 rc = EH_RESET_TIMER;
1447 done:
1448         spin_unlock(&session->lock);
1449         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1450         return rc;
1451 }
1452
1453 static void iscsi_check_transport_timeouts(unsigned long data)
1454 {
1455         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1456         struct iscsi_session *session = conn->session;
1457         unsigned long recv_timeout, next_timeout = 0, last_recv;
1458
1459         spin_lock(&session->lock);
1460         if (session->state != ISCSI_STATE_LOGGED_IN)
1461                 goto done;
1462
1463         recv_timeout = conn->recv_timeout;
1464         if (!recv_timeout)
1465                 goto done;
1466
1467         recv_timeout *= HZ;
1468         last_recv = conn->last_recv;
1469         if (conn->ping_mtask &&
1470             time_before_eq(conn->last_ping + (conn->ping_timeout * HZ),
1471                            jiffies)) {
1472                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1473                                   "expired, last rx %lu, last ping %lu, "
1474                                   "now %lu\n", conn->ping_timeout, last_recv,
1475                                   conn->last_ping, jiffies);
1476                 spin_unlock(&session->lock);
1477                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1478                 return;
1479         }
1480
1481         if (time_before_eq(last_recv + recv_timeout, jiffies)) {
1482                 /* send a ping to try to provoke some traffic */
1483                 debug_scsi("Sending nopout as ping on conn %p\n", conn);
1484                 iscsi_send_nopout(conn, NULL);
1485                 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
1486         } else
1487                 next_timeout = last_recv + 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 iscsi_cls_session *cls_session;
1510         struct iscsi_session *session;
1511         struct iscsi_conn *conn;
1512         struct iscsi_cmd_task *ctask;
1513         struct iscsi_tm *hdr;
1514         int rc, age;
1515
1516         cls_session = starget_to_session(scsi_target(sc->device));
1517         session = cls_session->dd_data;
1518
1519         mutex_lock(&session->eh_mutex);
1520         spin_lock_bh(&session->lock);
1521         /*
1522          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1523          * got the command.
1524          */
1525         if (!sc->SCp.ptr) {
1526                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1527                 spin_unlock_bh(&session->lock);
1528                 mutex_unlock(&session->eh_mutex);
1529                 return SUCCESS;
1530         }
1531
1532         /*
1533          * If we are not logged in or we have started a new session
1534          * then let the host reset code handle this
1535          */
1536         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1537             sc->SCp.phase != session->age) {
1538                 spin_unlock_bh(&session->lock);
1539                 mutex_unlock(&session->eh_mutex);
1540                 return FAILED;
1541         }
1542
1543         conn = session->leadconn;
1544         conn->eh_abort_cnt++;
1545         age = session->age;
1546
1547         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1548         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1549
1550         /* ctask completed before time out */
1551         if (!ctask->sc) {
1552                 debug_scsi("sc completed while abort in progress\n");
1553                 goto success;
1554         }
1555
1556         if (ctask->state == ISCSI_TASK_PENDING) {
1557                 fail_command(conn, ctask, DID_ABORT << 16);
1558                 goto success;
1559         }
1560
1561         /* only have one tmf outstanding at a time */
1562         if (conn->tmf_state != TMF_INITIAL)
1563                 goto failed;
1564         conn->tmf_state = TMF_QUEUED;
1565
1566         hdr = &conn->tmhdr;
1567         iscsi_prep_abort_task_pdu(ctask, hdr);
1568
1569         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1570                 rc = FAILED;
1571                 goto failed;
1572         }
1573
1574         switch (conn->tmf_state) {
1575         case TMF_SUCCESS:
1576                 spin_unlock_bh(&session->lock);
1577                 iscsi_suspend_tx(conn);
1578                 /*
1579                  * clean up task if aborted. grab the recv lock as a writer
1580                  */
1581                 write_lock_bh(conn->recv_lock);
1582                 spin_lock(&session->lock);
1583                 fail_command(conn, ctask, DID_ABORT << 16);
1584                 conn->tmf_state = TMF_INITIAL;
1585                 spin_unlock(&session->lock);
1586                 write_unlock_bh(conn->recv_lock);
1587                 iscsi_start_tx(conn);
1588                 goto success_unlocked;
1589         case TMF_TIMEDOUT:
1590                 spin_unlock_bh(&session->lock);
1591                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1592                 goto failed_unlocked;
1593         case TMF_NOT_FOUND:
1594                 if (!sc->SCp.ptr) {
1595                         conn->tmf_state = TMF_INITIAL;
1596                         /* ctask completed before tmf abort response */
1597                         debug_scsi("sc completed while abort in progress\n");
1598                         goto success;
1599                 }
1600                 /* fall through */
1601         default:
1602                 conn->tmf_state = TMF_INITIAL;
1603                 goto failed;
1604         }
1605
1606 success:
1607         spin_unlock_bh(&session->lock);
1608 success_unlocked:
1609         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1610         mutex_unlock(&session->eh_mutex);
1611         return SUCCESS;
1612
1613 failed:
1614         spin_unlock_bh(&session->lock);
1615 failed_unlocked:
1616         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1617                     ctask ? ctask->itt : 0);
1618         mutex_unlock(&session->eh_mutex);
1619         return FAILED;
1620 }
1621 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1622
1623 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1624 {
1625         memset(hdr, 0, sizeof(*hdr));
1626         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1627         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1628         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1629         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1630         hdr->rtt = RESERVED_ITT;
1631 }
1632
1633 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1634 {
1635         struct iscsi_cls_session *cls_session;
1636         struct iscsi_session *session;
1637         struct iscsi_conn *conn;
1638         struct iscsi_tm *hdr;
1639         int rc = FAILED;
1640
1641         cls_session = starget_to_session(scsi_target(sc->device));
1642         session = cls_session->dd_data;
1643
1644         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1645
1646         mutex_lock(&session->eh_mutex);
1647         spin_lock_bh(&session->lock);
1648         /*
1649          * Just check if we are not logged in. We cannot check for
1650          * the phase because the reset could come from a ioctl.
1651          */
1652         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1653                 goto unlock;
1654         conn = session->leadconn;
1655
1656         /* only have one tmf outstanding at a time */
1657         if (conn->tmf_state != TMF_INITIAL)
1658                 goto unlock;
1659         conn->tmf_state = TMF_QUEUED;
1660
1661         hdr = &conn->tmhdr;
1662         iscsi_prep_lun_reset_pdu(sc, hdr);
1663
1664         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1665                                     session->lu_reset_timeout)) {
1666                 rc = FAILED;
1667                 goto unlock;
1668         }
1669
1670         switch (conn->tmf_state) {
1671         case TMF_SUCCESS:
1672                 break;
1673         case TMF_TIMEDOUT:
1674                 spin_unlock_bh(&session->lock);
1675                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1676                 goto done;
1677         default:
1678                 conn->tmf_state = TMF_INITIAL;
1679                 goto unlock;
1680         }
1681
1682         rc = SUCCESS;
1683         spin_unlock_bh(&session->lock);
1684
1685         iscsi_suspend_tx(conn);
1686         /* need to grab the recv lock then session lock */
1687         write_lock_bh(conn->recv_lock);
1688         spin_lock(&session->lock);
1689         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1690         conn->tmf_state = TMF_INITIAL;
1691         spin_unlock(&session->lock);
1692         write_unlock_bh(conn->recv_lock);
1693
1694         iscsi_start_tx(conn);
1695         goto done;
1696
1697 unlock:
1698         spin_unlock_bh(&session->lock);
1699 done:
1700         debug_scsi("iscsi_eh_device_reset %s\n",
1701                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1702         mutex_unlock(&session->eh_mutex);
1703         return rc;
1704 }
1705 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1706
1707 /*
1708  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1709  * should be accessed via kfifo_{get,put} on q->queue.
1710  * Optionally, the caller can obtain the array of object pointers
1711  * by passing in a non-NULL @items pointer
1712  */
1713 int
1714 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1715 {
1716         int i, num_arrays = 1;
1717
1718         memset(q, 0, sizeof(*q));
1719
1720         q->max = max;
1721
1722         /* If the user passed an items pointer, he wants a copy of
1723          * the array. */
1724         if (items)
1725                 num_arrays++;
1726         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1727         if (q->pool == NULL)
1728                 goto enomem;
1729
1730         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1731                               GFP_KERNEL, NULL);
1732         if (q->queue == ERR_PTR(-ENOMEM))
1733                 goto enomem;
1734
1735         for (i = 0; i < max; i++) {
1736                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1737                 if (q->pool[i] == NULL) {
1738                         q->max = i;
1739                         goto enomem;
1740                 }
1741                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1742         }
1743
1744         if (items) {
1745                 *items = q->pool + max;
1746                 memcpy(*items, q->pool, max * sizeof(void *));
1747         }
1748
1749         return 0;
1750
1751 enomem:
1752         iscsi_pool_free(q);
1753         return -ENOMEM;
1754 }
1755 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1756
1757 void iscsi_pool_free(struct iscsi_pool *q)
1758 {
1759         int i;
1760
1761         for (i = 0; i < q->max; i++)
1762                 kfree(q->pool[i]);
1763         if (q->pool)
1764                 kfree(q->pool);
1765 }
1766 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1767
1768 /**
1769  * iscsi_host_add - add host to system
1770  * @shost: scsi host
1771  * @pdev: parent device
1772  *
1773  * This should be called by partial offload and software iscsi drivers
1774  * to add a host to the system.
1775  */
1776 int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
1777 {
1778         return scsi_add_host(shost, pdev);
1779 }
1780 EXPORT_SYMBOL_GPL(iscsi_host_add);
1781
1782 /**
1783  * iscsi_host_alloc - allocate a host and driver data
1784  * @sht: scsi host template
1785  * @dd_data_size: driver host data size
1786  * @qdepth: default device queue depth
1787  *
1788  * This should be called by partial offload and software iscsi drivers.
1789  * To access the driver specific memory use the iscsi_host_priv() macro.
1790  */
1791 struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
1792                                    int dd_data_size, uint16_t qdepth)
1793 {
1794         struct Scsi_Host *shost;
1795
1796         shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
1797         if (!shost)
1798                 return NULL;
1799         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1800
1801         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1802                 if (qdepth != 0)
1803                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1804                                "Queue depth must be between 1 and %d.\n",
1805                                qdepth, ISCSI_MAX_CMD_PER_LUN);
1806                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1807         }
1808         shost->cmd_per_lun = qdepth;
1809         return shost;
1810 }
1811 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
1812
1813 /**
1814  * iscsi_host_remove - remove host and sessions
1815  * @shost: scsi host
1816  *
1817  * This will also remove any sessions attached to the host, but if userspace
1818  * is managing the session at the same time this will break. TODO: add
1819  * refcounting to the netlink iscsi interface so a rmmod or host hot unplug
1820  * does not remove the memory from under us.
1821  */
1822 void iscsi_host_remove(struct Scsi_Host *shost)
1823 {
1824         iscsi_host_for_each_session(shost, iscsi_session_teardown);
1825         scsi_remove_host(shost);
1826 }
1827 EXPORT_SYMBOL_GPL(iscsi_host_remove);
1828
1829 void iscsi_host_free(struct Scsi_Host *shost)
1830 {
1831         struct iscsi_host *ihost = shost_priv(shost);
1832
1833         kfree(ihost->netdev);
1834         kfree(ihost->hwaddress);
1835         kfree(ihost->initiatorname);
1836         scsi_host_put(shost);
1837 }
1838 EXPORT_SYMBOL_GPL(iscsi_host_free);
1839
1840 /**
1841  * iscsi_session_setup - create iscsi cls session and host and session
1842  * @iscsit: iscsi transport template
1843  * @shost: scsi host
1844  * @cmds_max: session can queue
1845  * @cmd_task_size: LLD ctask private data size
1846  * @mgmt_task_size: LLD mtask private data size
1847  * @initial_cmdsn: initial CmdSN
1848  *
1849  * This can be used by software iscsi_transports that allocate
1850  * a session per scsi host.
1851  */
1852 struct iscsi_cls_session *
1853 iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
1854                     uint16_t cmds_max, int cmd_task_size, int mgmt_task_size,
1855                     uint32_t initial_cmdsn)
1856 {
1857         struct iscsi_session *session;
1858         struct iscsi_cls_session *cls_session;
1859         int cmd_i;
1860
1861         if (!is_power_of_2(cmds_max) || cmds_max >= ISCSI_MGMT_ITT_OFFSET ||
1862             cmds_max < 2) {
1863                 if (cmds_max != 0)
1864                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1865                                "can_queue must be a power of 2 and between "
1866                                "2 and %d - setting to %d.\n", cmds_max,
1867                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1868                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1869         }
1870
1871         cls_session = iscsi_alloc_session(shost, iscsit,
1872                                           sizeof(struct iscsi_session));
1873         if (!cls_session)
1874                 return NULL;
1875         session = cls_session->dd_data;
1876         session->cls_session = cls_session;
1877         session->host = shost;
1878         session->state = ISCSI_STATE_FREE;
1879         session->fast_abort = 1;
1880         session->lu_reset_timeout = 15;
1881         session->abort_timeout = 10;
1882         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1883         session->cmds_max = cmds_max;
1884         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1885         session->exp_cmdsn = initial_cmdsn + 1;
1886         session->max_cmdsn = initial_cmdsn + 1;
1887         session->max_r2t = 1;
1888         session->tt = iscsit;
1889         mutex_init(&session->eh_mutex);
1890         spin_lock_init(&session->lock);
1891
1892         /* initialize SCSI PDU commands pool */
1893         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1894                             (void***)&session->cmds,
1895                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1896                 goto cmdpool_alloc_fail;
1897
1898         /* pre-format cmds pool with ITT */
1899         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1900                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1901
1902                 if (cmd_task_size)
1903                         ctask->dd_data = &ctask[1];
1904                 ctask->itt = cmd_i;
1905                 INIT_LIST_HEAD(&ctask->running);
1906         }
1907
1908         /* initialize immediate command pool */
1909         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1910                            (void***)&session->mgmt_cmds,
1911                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1912                 goto mgmtpool_alloc_fail;
1913
1914
1915         /* pre-format immediate cmds pool with ITT */
1916         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1917                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1918
1919                 if (mgmt_task_size)
1920                         mtask->dd_data = &mtask[1];
1921                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1922                 INIT_LIST_HEAD(&mtask->running);
1923         }
1924
1925         if (!try_module_get(iscsit->owner))
1926                 goto module_get_fail;
1927
1928         if (iscsi_add_session(cls_session, 0))
1929                 goto cls_session_fail;
1930         return cls_session;
1931
1932 cls_session_fail:
1933         module_put(iscsit->owner);
1934 module_get_fail:
1935         iscsi_pool_free(&session->mgmtpool);
1936 mgmtpool_alloc_fail:
1937         iscsi_pool_free(&session->cmdpool);
1938 cmdpool_alloc_fail:
1939         iscsi_free_session(cls_session);
1940         return NULL;
1941 }
1942 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1943
1944 /**
1945  * iscsi_session_teardown - destroy session, host, and cls_session
1946  * @cls_session: iscsi session
1947  *
1948  * The driver must have called iscsi_remove_session before
1949  * calling this.
1950  */
1951 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1952 {
1953         struct iscsi_session *session = cls_session->dd_data;
1954         struct module *owner = cls_session->transport->owner;
1955
1956         iscsi_pool_free(&session->mgmtpool);
1957         iscsi_pool_free(&session->cmdpool);
1958
1959         kfree(session->password);
1960         kfree(session->password_in);
1961         kfree(session->username);
1962         kfree(session->username_in);
1963         kfree(session->targetname);
1964
1965         iscsi_destroy_session(cls_session);
1966         module_put(owner);
1967 }
1968 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1969
1970 /**
1971  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1972  * @cls_session: iscsi_cls_session
1973  * @dd_size: private driver data size
1974  * @conn_idx: cid
1975  */
1976 struct iscsi_cls_conn *
1977 iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
1978                  uint32_t conn_idx)
1979 {
1980         struct iscsi_session *session = cls_session->dd_data;
1981         struct iscsi_conn *conn;
1982         struct iscsi_cls_conn *cls_conn;
1983         char *data;
1984
1985         cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
1986                                      conn_idx);
1987         if (!cls_conn)
1988                 return NULL;
1989         conn = cls_conn->dd_data;
1990         memset(conn, 0, sizeof(*conn) + dd_size);
1991
1992         conn->dd_data = cls_conn->dd_data + sizeof(*conn);
1993         conn->session = session;
1994         conn->cls_conn = cls_conn;
1995         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1996         conn->id = conn_idx;
1997         conn->exp_statsn = 0;
1998         conn->tmf_state = TMF_INITIAL;
1999
2000         init_timer(&conn->transport_timer);
2001         conn->transport_timer.data = (unsigned long)conn;
2002         conn->transport_timer.function = iscsi_check_transport_timeouts;
2003
2004         INIT_LIST_HEAD(&conn->run_list);
2005         INIT_LIST_HEAD(&conn->mgmt_run_list);
2006         INIT_LIST_HEAD(&conn->mgmtqueue);
2007         INIT_LIST_HEAD(&conn->xmitqueue);
2008         INIT_LIST_HEAD(&conn->requeue);
2009         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2010
2011         /* allocate login_mtask used for the login/text sequences */
2012         spin_lock_bh(&session->lock);
2013         if (!__kfifo_get(session->mgmtpool.queue,
2014                          (void*)&conn->login_mtask,
2015                          sizeof(void*))) {
2016                 spin_unlock_bh(&session->lock);
2017                 goto login_mtask_alloc_fail;
2018         }
2019         spin_unlock_bh(&session->lock);
2020
2021         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
2022         if (!data)
2023                 goto login_mtask_data_alloc_fail;
2024         conn->login_mtask->data = conn->data = data;
2025
2026         init_timer(&conn->tmf_timer);
2027         init_waitqueue_head(&conn->ehwait);
2028
2029         return cls_conn;
2030
2031 login_mtask_data_alloc_fail:
2032         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2033                     sizeof(void*));
2034 login_mtask_alloc_fail:
2035         iscsi_destroy_conn(cls_conn);
2036         return NULL;
2037 }
2038 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2039
2040 /**
2041  * iscsi_conn_teardown - teardown iscsi connection
2042  * cls_conn: iscsi class connection
2043  *
2044  * TODO: we may need to make this into a two step process
2045  * like scsi-mls remove + put host
2046  */
2047 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2048 {
2049         struct iscsi_conn *conn = cls_conn->dd_data;
2050         struct iscsi_session *session = conn->session;
2051         unsigned long flags;
2052
2053         del_timer_sync(&conn->transport_timer);
2054
2055         spin_lock_bh(&session->lock);
2056         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2057         if (session->leadconn == conn) {
2058                 /*
2059                  * leading connection? then give up on recovery.
2060                  */
2061                 session->state = ISCSI_STATE_TERMINATE;
2062                 wake_up(&conn->ehwait);
2063         }
2064         spin_unlock_bh(&session->lock);
2065
2066         /*
2067          * Block until all in-progress commands for this connection
2068          * time out or fail.
2069          */
2070         for (;;) {
2071                 spin_lock_irqsave(session->host->host_lock, flags);
2072                 if (!session->host->host_busy) { /* OK for ERL == 0 */
2073                         spin_unlock_irqrestore(session->host->host_lock, flags);
2074                         break;
2075                 }
2076                 spin_unlock_irqrestore(session->host->host_lock, flags);
2077                 msleep_interruptible(500);
2078                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2079                                   "host_busy %d host_failed %d\n",
2080                                   session->host->host_busy,
2081                                   session->host->host_failed);
2082                 /*
2083                  * force eh_abort() to unblock
2084                  */
2085                 wake_up(&conn->ehwait);
2086         }
2087
2088         /* flush queued up work because we free the connection below */
2089         iscsi_suspend_tx(conn);
2090
2091         spin_lock_bh(&session->lock);
2092         kfree(conn->data);
2093         kfree(conn->persistent_address);
2094         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2095                     sizeof(void*));
2096         if (session->leadconn == conn)
2097                 session->leadconn = NULL;
2098         spin_unlock_bh(&session->lock);
2099
2100         iscsi_destroy_conn(cls_conn);
2101 }
2102 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2103
2104 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2105 {
2106         struct iscsi_conn *conn = cls_conn->dd_data;
2107         struct iscsi_session *session = conn->session;
2108
2109         if (!session) {
2110                 iscsi_conn_printk(KERN_ERR, conn,
2111                                   "can't start unbound connection\n");
2112                 return -EPERM;
2113         }
2114
2115         if ((session->imm_data_en || !session->initial_r2t_en) &&
2116              session->first_burst > session->max_burst) {
2117                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2118                                   "first_burst %d max_burst %d\n",
2119                                   session->first_burst, session->max_burst);
2120                 return -EINVAL;
2121         }
2122
2123         if (conn->ping_timeout && !conn->recv_timeout) {
2124                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2125                                   "zero. Using 5 seconds\n.");
2126                 conn->recv_timeout = 5;
2127         }
2128
2129         if (conn->recv_timeout && !conn->ping_timeout) {
2130                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2131                                   "zero. Using 5 seconds.\n");
2132                 conn->ping_timeout = 5;
2133         }
2134
2135         spin_lock_bh(&session->lock);
2136         conn->c_stage = ISCSI_CONN_STARTED;
2137         session->state = ISCSI_STATE_LOGGED_IN;
2138         session->queued_cmdsn = session->cmdsn;
2139
2140         conn->last_recv = jiffies;
2141         conn->last_ping = jiffies;
2142         if (conn->recv_timeout && conn->ping_timeout)
2143                 mod_timer(&conn->transport_timer,
2144                           jiffies + (conn->recv_timeout * HZ));
2145
2146         switch(conn->stop_stage) {
2147         case STOP_CONN_RECOVER:
2148                 /*
2149                  * unblock eh_abort() if it is blocked. re-try all
2150                  * commands after successful recovery
2151                  */
2152                 conn->stop_stage = 0;
2153                 conn->tmf_state = TMF_INITIAL;
2154                 session->age++;
2155                 if (session->age == 16)
2156                         session->age = 0;
2157                 break;
2158         case STOP_CONN_TERM:
2159                 conn->stop_stage = 0;
2160                 break;
2161         default:
2162                 break;
2163         }
2164         spin_unlock_bh(&session->lock);
2165
2166         iscsi_unblock_session(session->cls_session);
2167         wake_up(&conn->ehwait);
2168         return 0;
2169 }
2170 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2171
2172 static void
2173 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2174 {
2175         struct iscsi_mgmt_task *mtask, *tmp;
2176
2177         /* handle pending */
2178         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2179                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2180                 iscsi_free_mgmt_task(conn, mtask);
2181         }
2182
2183         /* handle running */
2184         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2185                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2186                 iscsi_free_mgmt_task(conn, mtask);
2187         }
2188
2189         conn->mtask = NULL;
2190 }
2191
2192 static void iscsi_start_session_recovery(struct iscsi_session *session,
2193                                          struct iscsi_conn *conn, int flag)
2194 {
2195         int old_stop_stage;
2196
2197         del_timer_sync(&conn->transport_timer);
2198
2199         mutex_lock(&session->eh_mutex);
2200         spin_lock_bh(&session->lock);
2201         if (conn->stop_stage == STOP_CONN_TERM) {
2202                 spin_unlock_bh(&session->lock);
2203                 mutex_unlock(&session->eh_mutex);
2204                 return;
2205         }
2206
2207         /*
2208          * The LLD either freed/unset the lock on us, or userspace called
2209          * stop but did not create a proper connection (connection was never
2210          * bound or it was unbound then stop was called).
2211          */
2212         if (!conn->recv_lock) {
2213                 spin_unlock_bh(&session->lock);
2214                 mutex_unlock(&session->eh_mutex);
2215                 return;
2216         }
2217
2218         /*
2219          * When this is called for the in_login state, we only want to clean
2220          * up the login task and connection. We do not need to block and set
2221          * the recovery state again
2222          */
2223         if (flag == STOP_CONN_TERM)
2224                 session->state = ISCSI_STATE_TERMINATE;
2225         else if (conn->stop_stage != STOP_CONN_RECOVER)
2226                 session->state = ISCSI_STATE_IN_RECOVERY;
2227
2228         old_stop_stage = conn->stop_stage;
2229         conn->stop_stage = flag;
2230         conn->c_stage = ISCSI_CONN_STOPPED;
2231         spin_unlock_bh(&session->lock);
2232
2233         iscsi_suspend_tx(conn);
2234
2235         write_lock_bh(conn->recv_lock);
2236         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2237         write_unlock_bh(conn->recv_lock);
2238
2239         /*
2240          * for connection level recovery we should not calculate
2241          * header digest. conn->hdr_size used for optimization
2242          * in hdr_extract() and will be re-negotiated at
2243          * set_param() time.
2244          */
2245         if (flag == STOP_CONN_RECOVER) {
2246                 conn->hdrdgst_en = 0;
2247                 conn->datadgst_en = 0;
2248                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2249                     old_stop_stage != STOP_CONN_RECOVER) {
2250                         debug_scsi("blocking session\n");
2251                         iscsi_block_session(session->cls_session);
2252                 }
2253         }
2254
2255         /*
2256          * flush queues.
2257          */
2258         spin_lock_bh(&session->lock);
2259         fail_all_commands(conn, -1,
2260                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2261         flush_control_queues(session, conn);
2262         spin_unlock_bh(&session->lock);
2263         mutex_unlock(&session->eh_mutex);
2264 }
2265
2266 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2267 {
2268         struct iscsi_conn *conn = cls_conn->dd_data;
2269         struct iscsi_session *session = conn->session;
2270
2271         switch (flag) {
2272         case STOP_CONN_RECOVER:
2273         case STOP_CONN_TERM:
2274                 iscsi_start_session_recovery(session, conn, flag);
2275                 break;
2276         default:
2277                 iscsi_conn_printk(KERN_ERR, conn,
2278                                   "invalid stop flag %d\n", flag);
2279         }
2280 }
2281 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2282
2283 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2284                     struct iscsi_cls_conn *cls_conn, int is_leading)
2285 {
2286         struct iscsi_session *session = cls_session->dd_data;
2287         struct iscsi_conn *conn = cls_conn->dd_data;
2288
2289         spin_lock_bh(&session->lock);
2290         if (is_leading)
2291                 session->leadconn = conn;
2292         spin_unlock_bh(&session->lock);
2293
2294         /*
2295          * Unblock xmitworker(), Login Phase will pass through.
2296          */
2297         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2298         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2299         return 0;
2300 }
2301 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2302
2303
2304 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2305                     enum iscsi_param param, char *buf, int buflen)
2306 {
2307         struct iscsi_conn *conn = cls_conn->dd_data;
2308         struct iscsi_session *session = conn->session;
2309         uint32_t value;
2310
2311         switch(param) {
2312         case ISCSI_PARAM_FAST_ABORT:
2313                 sscanf(buf, "%d", &session->fast_abort);
2314                 break;
2315         case ISCSI_PARAM_ABORT_TMO:
2316                 sscanf(buf, "%d", &session->abort_timeout);
2317                 break;
2318         case ISCSI_PARAM_LU_RESET_TMO:
2319                 sscanf(buf, "%d", &session->lu_reset_timeout);
2320                 break;
2321         case ISCSI_PARAM_PING_TMO:
2322                 sscanf(buf, "%d", &conn->ping_timeout);
2323                 break;
2324         case ISCSI_PARAM_RECV_TMO:
2325                 sscanf(buf, "%d", &conn->recv_timeout);
2326                 break;
2327         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2328                 sscanf(buf, "%d", &conn->max_recv_dlength);
2329                 break;
2330         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2331                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2332                 break;
2333         case ISCSI_PARAM_HDRDGST_EN:
2334                 sscanf(buf, "%d", &conn->hdrdgst_en);
2335                 break;
2336         case ISCSI_PARAM_DATADGST_EN:
2337                 sscanf(buf, "%d", &conn->datadgst_en);
2338                 break;
2339         case ISCSI_PARAM_INITIAL_R2T_EN:
2340                 sscanf(buf, "%d", &session->initial_r2t_en);
2341                 break;
2342         case ISCSI_PARAM_MAX_R2T:
2343                 sscanf(buf, "%d", &session->max_r2t);
2344                 break;
2345         case ISCSI_PARAM_IMM_DATA_EN:
2346                 sscanf(buf, "%d", &session->imm_data_en);
2347                 break;
2348         case ISCSI_PARAM_FIRST_BURST:
2349                 sscanf(buf, "%d", &session->first_burst);
2350                 break;
2351         case ISCSI_PARAM_MAX_BURST:
2352                 sscanf(buf, "%d", &session->max_burst);
2353                 break;
2354         case ISCSI_PARAM_PDU_INORDER_EN:
2355                 sscanf(buf, "%d", &session->pdu_inorder_en);
2356                 break;
2357         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2358                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2359                 break;
2360         case ISCSI_PARAM_ERL:
2361                 sscanf(buf, "%d", &session->erl);
2362                 break;
2363         case ISCSI_PARAM_IFMARKER_EN:
2364                 sscanf(buf, "%d", &value);
2365                 BUG_ON(value);
2366                 break;
2367         case ISCSI_PARAM_OFMARKER_EN:
2368                 sscanf(buf, "%d", &value);
2369                 BUG_ON(value);
2370                 break;
2371         case ISCSI_PARAM_EXP_STATSN:
2372                 sscanf(buf, "%u", &conn->exp_statsn);
2373                 break;
2374         case ISCSI_PARAM_USERNAME:
2375                 kfree(session->username);
2376                 session->username = kstrdup(buf, GFP_KERNEL);
2377                 if (!session->username)
2378                         return -ENOMEM;
2379                 break;
2380         case ISCSI_PARAM_USERNAME_IN:
2381                 kfree(session->username_in);
2382                 session->username_in = kstrdup(buf, GFP_KERNEL);
2383                 if (!session->username_in)
2384                         return -ENOMEM;
2385                 break;
2386         case ISCSI_PARAM_PASSWORD:
2387                 kfree(session->password);
2388                 session->password = kstrdup(buf, GFP_KERNEL);
2389                 if (!session->password)
2390                         return -ENOMEM;
2391                 break;
2392         case ISCSI_PARAM_PASSWORD_IN:
2393                 kfree(session->password_in);
2394                 session->password_in = kstrdup(buf, GFP_KERNEL);
2395                 if (!session->password_in)
2396                         return -ENOMEM;
2397                 break;
2398         case ISCSI_PARAM_TARGET_NAME:
2399                 /* this should not change between logins */
2400                 if (session->targetname)
2401                         break;
2402
2403                 session->targetname = kstrdup(buf, GFP_KERNEL);
2404                 if (!session->targetname)
2405                         return -ENOMEM;
2406                 break;
2407         case ISCSI_PARAM_TPGT:
2408                 sscanf(buf, "%d", &session->tpgt);
2409                 break;
2410         case ISCSI_PARAM_PERSISTENT_PORT:
2411                 sscanf(buf, "%d", &conn->persistent_port);
2412                 break;
2413         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2414                 /*
2415                  * this is the address returned in discovery so it should
2416                  * not change between logins.
2417                  */
2418                 if (conn->persistent_address)
2419                         break;
2420
2421                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2422                 if (!conn->persistent_address)
2423                         return -ENOMEM;
2424                 break;
2425         default:
2426                 return -ENOSYS;
2427         }
2428
2429         return 0;
2430 }
2431 EXPORT_SYMBOL_GPL(iscsi_set_param);
2432
2433 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2434                             enum iscsi_param param, char *buf)
2435 {
2436         struct iscsi_session *session = cls_session->dd_data;
2437         int len;
2438
2439         switch(param) {
2440         case ISCSI_PARAM_FAST_ABORT:
2441                 len = sprintf(buf, "%d\n", session->fast_abort);
2442                 break;
2443         case ISCSI_PARAM_ABORT_TMO:
2444                 len = sprintf(buf, "%d\n", session->abort_timeout);
2445                 break;
2446         case ISCSI_PARAM_LU_RESET_TMO:
2447                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2448                 break;
2449         case ISCSI_PARAM_INITIAL_R2T_EN:
2450                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2451                 break;
2452         case ISCSI_PARAM_MAX_R2T:
2453                 len = sprintf(buf, "%hu\n", session->max_r2t);
2454                 break;
2455         case ISCSI_PARAM_IMM_DATA_EN:
2456                 len = sprintf(buf, "%d\n", session->imm_data_en);
2457                 break;
2458         case ISCSI_PARAM_FIRST_BURST:
2459                 len = sprintf(buf, "%u\n", session->first_burst);
2460                 break;
2461         case ISCSI_PARAM_MAX_BURST:
2462                 len = sprintf(buf, "%u\n", session->max_burst);
2463                 break;
2464         case ISCSI_PARAM_PDU_INORDER_EN:
2465                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2466                 break;
2467         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2468                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2469                 break;
2470         case ISCSI_PARAM_ERL:
2471                 len = sprintf(buf, "%d\n", session->erl);
2472                 break;
2473         case ISCSI_PARAM_TARGET_NAME:
2474                 len = sprintf(buf, "%s\n", session->targetname);
2475                 break;
2476         case ISCSI_PARAM_TPGT:
2477                 len = sprintf(buf, "%d\n", session->tpgt);
2478                 break;
2479         case ISCSI_PARAM_USERNAME:
2480                 len = sprintf(buf, "%s\n", session->username);
2481                 break;
2482         case ISCSI_PARAM_USERNAME_IN:
2483                 len = sprintf(buf, "%s\n", session->username_in);
2484                 break;
2485         case ISCSI_PARAM_PASSWORD:
2486                 len = sprintf(buf, "%s\n", session->password);
2487                 break;
2488         case ISCSI_PARAM_PASSWORD_IN:
2489                 len = sprintf(buf, "%s\n", session->password_in);
2490                 break;
2491         default:
2492                 return -ENOSYS;
2493         }
2494
2495         return len;
2496 }
2497 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2498
2499 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2500                          enum iscsi_param param, char *buf)
2501 {
2502         struct iscsi_conn *conn = cls_conn->dd_data;
2503         int len;
2504
2505         switch(param) {
2506         case ISCSI_PARAM_PING_TMO:
2507                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2508                 break;
2509         case ISCSI_PARAM_RECV_TMO:
2510                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2511                 break;
2512         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2513                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2514                 break;
2515         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2516                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2517                 break;
2518         case ISCSI_PARAM_HDRDGST_EN:
2519                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2520                 break;
2521         case ISCSI_PARAM_DATADGST_EN:
2522                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2523                 break;
2524         case ISCSI_PARAM_IFMARKER_EN:
2525                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2526                 break;
2527         case ISCSI_PARAM_OFMARKER_EN:
2528                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2529                 break;
2530         case ISCSI_PARAM_EXP_STATSN:
2531                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2532                 break;
2533         case ISCSI_PARAM_PERSISTENT_PORT:
2534                 len = sprintf(buf, "%d\n", conn->persistent_port);
2535                 break;
2536         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2537                 len = sprintf(buf, "%s\n", conn->persistent_address);
2538                 break;
2539         default:
2540                 return -ENOSYS;
2541         }
2542
2543         return len;
2544 }
2545 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2546
2547 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2548                          char *buf)
2549 {
2550         struct iscsi_host *ihost = shost_priv(shost);
2551         int len;
2552
2553         switch (param) {
2554         case ISCSI_HOST_PARAM_NETDEV_NAME:
2555                 if (!ihost->netdev)
2556                         len = sprintf(buf, "%s\n", "default");
2557                 else
2558                         len = sprintf(buf, "%s\n", ihost->netdev);
2559                 break;
2560         case ISCSI_HOST_PARAM_HWADDRESS:
2561                 if (!ihost->hwaddress)
2562                         len = sprintf(buf, "%s\n", "default");
2563                 else
2564                         len = sprintf(buf, "%s\n", ihost->hwaddress);
2565                 break;
2566         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2567                 if (!ihost->initiatorname)
2568                         len = sprintf(buf, "%s\n", "unknown");
2569                 else
2570                         len = sprintf(buf, "%s\n", ihost->initiatorname);
2571                 break;
2572         case ISCSI_HOST_PARAM_IPADDRESS:
2573                 if (!strlen(ihost->local_address))
2574                         len = sprintf(buf, "%s\n", "unknown");
2575                 else
2576                         len = sprintf(buf, "%s\n",
2577                                       ihost->local_address);
2578         default:
2579                 return -ENOSYS;
2580         }
2581
2582         return len;
2583 }
2584 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2585
2586 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2587                          char *buf, int buflen)
2588 {
2589         struct iscsi_host *ihost = shost_priv(shost);
2590
2591         switch (param) {
2592         case ISCSI_HOST_PARAM_NETDEV_NAME:
2593                 if (!ihost->netdev)
2594                         ihost->netdev = kstrdup(buf, GFP_KERNEL);
2595                 break;
2596         case ISCSI_HOST_PARAM_HWADDRESS:
2597                 if (!ihost->hwaddress)
2598                         ihost->hwaddress = kstrdup(buf, GFP_KERNEL);
2599                 break;
2600         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2601                 if (!ihost->initiatorname)
2602                         ihost->initiatorname = kstrdup(buf, GFP_KERNEL);
2603                 break;
2604         default:
2605                 return -ENOSYS;
2606         }
2607
2608         return 0;
2609 }
2610 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2611
2612 MODULE_AUTHOR("Mike Christie");
2613 MODULE_DESCRIPTION("iSCSI library functions");
2614 MODULE_LICENSE("GPL");