SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/scsi/libiscsi.c

   1 /*
   2  * iSCSI lib functions
   3  *
   4  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   5  * Copyright (C) 2004 - 2006 Mike Christie
   6  * Copyright (C) 2004 - 2005 Dmitry Yusupov
   7  * Copyright (C) 2004 - 2005 Alex Aizman
   8  * maintained by open-iscsi@googlegroups.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  */
  24 #include <linux/types.h>
  25 #include <linux/kfifo.h>
  26 #include <linux/delay.h>
  27 #include <linux/log2.h>
  28 #include <asm/unaligned.h>
  29 #include <net/tcp.h>
  30 #include <scsi/scsi_cmnd.h>
  31 #include <scsi/scsi_device.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_tcq.h>
  34 #include <scsi/scsi_host.h>
  35 #include <scsi/scsi.h>
  36 #include <scsi/iscsi_proto.h>
  37 #include <scsi/scsi_transport.h>
  38 #include <scsi/scsi_transport_iscsi.h>
  39 #include <scsi/libiscsi.h>
  40
  41 /* 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         rc = iscsi_verify_itt(conn, hdr->itt);
 644         if (rc)
 645                 return rc;
 646
 647         if (hdr->itt != RESERVED_ITT)
 648                 itt = get_itt(hdr->itt);
 649         else
 650                 itt = ~0U;
 651
 652         if (itt < session->cmds_max) {
 653                 ctask = session->cmds[itt];
 654
 655                 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 656                            opcode, conn->id, ctask->itt, datalen);
 657
 658                 switch(opcode) {
 659                 case ISCSI_OP_SCSI_CMD_RSP:
 660                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 661                         iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
 662                                            datalen);
 663                         break;
 664                 case ISCSI_OP_SCSI_DATA_IN:
 665                         BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
 666                         if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
 667                                 conn->scsirsp_pdus_cnt++;
 668                                 __iscsi_put_ctask(ctask);
 669                         }
 670                         break;
 671                 case ISCSI_OP_R2T:
 672                         /* LLD handles this for now */
 673                         break;
 674                 default:
 675                         rc = ISCSI_ERR_BAD_OPCODE;
 676                         break;
 677                 }
 678         } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
 679                    itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
 680                 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
 681
 682                 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
 683                            opcode, conn->id, mtask->itt, datalen);
 684
 685                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 686                 switch(opcode) {
 687                 case ISCSI_OP_LOGOUT_RSP:
 688                         if (datalen) {
 689                                 rc = ISCSI_ERR_PROTO;
 690                                 break;
 691                         }
 692                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 693                         /* fall through */
 694                 case ISCSI_OP_LOGIN_RSP:
 695                 case ISCSI_OP_TEXT_RSP:
 696                         /*
 697                          * login related PDU's exp_statsn is handled in
 698                          * userspace
 699                          */
 700                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 701                                 rc = ISCSI_ERR_CONN_FAILED;
 702                         iscsi_free_mgmt_task(conn, mtask);
 703                         break;
 704                 case ISCSI_OP_SCSI_TMFUNC_RSP:
 705                         if (datalen) {
 706                                 rc = ISCSI_ERR_PROTO;
 707                                 break;
 708                         }
 709
 710                         iscsi_tmf_rsp(conn, hdr);
 711                         iscsi_free_mgmt_task(conn, mtask);
 712                         break;
 713                 case ISCSI_OP_NOOP_IN:
 714                         if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
 715                             datalen) {
 716                                 rc = ISCSI_ERR_PROTO;
 717                                 break;
 718                         }
 719                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 720
 721                         if (conn->ping_mtask != mtask) {
 722                                 /*
 723                                  * If this is not in response to one of our
 724                                  * nops then it must be from userspace.
 725                                  */
 726                                 if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
 727                                                    datalen))
 728                                         rc = ISCSI_ERR_CONN_FAILED;
 729                         } else
 730                                 mod_timer(&conn->transport_timer,
 731                                           jiffies + conn->recv_timeout);
 732                         iscsi_free_mgmt_task(conn, mtask);
 733                         break;
 734                 default:
 735                         rc = ISCSI_ERR_BAD_OPCODE;
 736                         break;
 737                 }
 738         } else if (itt == ~0U) {
 739                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 740
 741                 switch(opcode) {
 742                 case ISCSI_OP_NOOP_IN:
 743                         if (datalen) {
 744                                 rc = ISCSI_ERR_PROTO;
 745                                 break;
 746                         }
 747
 748                         if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
 749                                 break;
 750
 751                         iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 752                         break;
 753                 case ISCSI_OP_REJECT:
 754                         rc = iscsi_handle_reject(conn, hdr, data, datalen);
 755                         break;
 756                 case ISCSI_OP_ASYNC_EVENT:
 757                         conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 758                         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
 759                                 rc = ISCSI_ERR_CONN_FAILED;
 760                         break;
 761                 default:
 762                         rc = ISCSI_ERR_BAD_OPCODE;
 763                         break;
 764                 }
 765         } else
 766                 rc = ISCSI_ERR_BAD_ITT;
 767
 768         return rc;
 769 }
 770
 771 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 772                        char *data, int datalen)
 773 {
 774         int rc;
 775
 776         spin_lock(&conn->session->lock);
 777         rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
 778         spin_unlock(&conn->session->lock);
 779         return rc;
 780 }
 781 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 782
 783 int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
 784 {
 785         struct iscsi_session *session = conn->session;
 786         struct iscsi_cmd_task *ctask;
 787
 788         if (itt == RESERVED_ITT)
 789                 return 0;
 790
 791         if (((__force u32)itt & ISCSI_AGE_MASK) !=
 792             (session->age << ISCSI_AGE_SHIFT)) {
 793                 iscsi_conn_printk(KERN_ERR, conn,
 794                                   "received itt %x expected session age (%x)\n",
 795                                   (__force u32)itt,
 796                                   session->age & ISCSI_AGE_MASK);
 797                 return ISCSI_ERR_BAD_ITT;
 798         }
 799
 800         if (itt < session->cmds_max) {
 801                 ctask = session->cmds[itt];
 802
 803                 if (!ctask->sc) {
 804                         iscsi_conn_printk(KERN_INFO, conn, "dropping ctask "
 805                                           "with itt 0x%x\n", ctask->itt);
 806                         /* force drop */
 807                         return ISCSI_ERR_NO_SCSI_CMD;
 808                 }
 809
 810                 if (ctask->sc->SCp.phase != session->age) {
 811                         iscsi_conn_printk(KERN_ERR, conn,
 812                                           "iscsi: ctask's session age %d, "
 813                                           "expected %d\n", ctask->sc->SCp.phase,
 814                                           session->age);
 815                         return ISCSI_ERR_SESSION_FAILED;
 816                 }
 817         }
 818
 819         return 0;
 820 }
 821 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 822
 823 struct iscsi_cmd_task *
 824 iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
 825 {
 826         struct iscsi_session *session = conn->session;
 827         struct iscsi_cmd_task *ctask;
 828         uint32_t i;
 829
 830         if (iscsi_verify_itt(conn, itt))
 831                 return NULL;
 832
 833         if (itt == RESERVED_ITT)
 834                 return NULL;
 835
 836         i = get_itt(itt);
 837         if (i >= session->cmds_max)
 838                 return NULL;
 839
 840         ctask = session->cmds[i];
 841         if (!ctask->sc)
 842                 return NULL;
 843
 844         if (ctask->sc->SCp.phase != session->age)
 845                 return NULL;
 846
 847         return ctask;
 848 }
 849 EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
 850
 851 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 852 {
 853         struct iscsi_session *session = conn->session;
 854         unsigned long flags;
 855
 856         spin_lock_irqsave(&session->lock, flags);
 857         if (session->state == ISCSI_STATE_FAILED) {
 858                 spin_unlock_irqrestore(&session->lock, flags);
 859                 return;
 860         }
 861
 862         if (conn->stop_stage == 0)
 863                 session->state = ISCSI_STATE_FAILED;
 864         spin_unlock_irqrestore(&session->lock, flags);
 865         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 866         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
 867         iscsi_conn_error(conn->cls_conn, err);
 868 }
 869 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 870
 871 static void iscsi_prep_mtask(struct iscsi_conn *conn,
 872                              struct iscsi_mgmt_task *mtask)
 873 {
 874         struct iscsi_session *session = conn->session;
 875         struct iscsi_hdr *hdr = mtask->hdr;
 876         struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 877
 878         if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
 879             hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
 880                 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 881         /*
 882          * pre-format CmdSN for outgoing PDU.
 883          */
 884         nop->cmdsn = cpu_to_be32(session->cmdsn);
 885         if (hdr->itt != RESERVED_ITT) {
 886                 hdr->itt = build_itt(mtask->itt, session->age);
 887                 /*
 888                  * TODO: We always use immediate, so we never hit this.
 889                  * If we start to send tmfs or nops as non-immediate then
 890                  * we should start checking the cmdsn numbers for mgmt tasks.
 891                  */
 892                 if (conn->c_stage == ISCSI_CONN_STARTED &&
 893                     !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 894                         session->queued_cmdsn++;
 895                         session->cmdsn++;
 896                 }
 897         }
 898
 899         if (session->tt->init_mgmt_task)
 900                 session->tt->init_mgmt_task(conn, mtask);
 901
 902         debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
 903                    hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
 904                    mtask->data_count);
 905 }
 906
 907 static int iscsi_xmit_mtask(struct iscsi_conn *conn)
 908 {
 909         struct iscsi_hdr *hdr = conn->mtask->hdr;
 910         int rc;
 911
 912         if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 913                 conn->session->state = ISCSI_STATE_LOGGING_OUT;
 914         spin_unlock_bh(&conn->session->lock);
 915
 916         rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
 917         spin_lock_bh(&conn->session->lock);
 918         if (rc)
 919                 return rc;
 920
 921         /* done with this in-progress mtask */
 922         conn->mtask = NULL;
 923         return 0;
 924 }
 925
 926 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 927 {
 928         struct iscsi_session *session = conn->session;
 929
 930         /*
 931          * Check for iSCSI window and take care of CmdSN wrap-around
 932          */
 933         if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
 934                 debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
 935                            "CmdSN %u/%u\n", session->exp_cmdsn,
 936                            session->max_cmdsn, session->cmdsn,
 937                            session->queued_cmdsn);
 938                 return -ENOSPC;
 939         }
 940         return 0;
 941 }
 942
 943 static int iscsi_xmit_ctask(struct iscsi_conn *conn)
 944 {
 945         struct iscsi_cmd_task *ctask = conn->ctask;
 946         int rc;
 947
 948         __iscsi_get_ctask(ctask);
 949         spin_unlock_bh(&conn->session->lock);
 950         rc = conn->session->tt->xmit_cmd_task(conn, ctask);
 951         spin_lock_bh(&conn->session->lock);
 952         __iscsi_put_ctask(ctask);
 953         if (!rc)
 954                 /* done with this ctask */
 955                 conn->ctask = NULL;
 956         return rc;
 957 }
 958
 959 /**
 960  * iscsi_requeue_ctask - requeue ctask to run from session workqueue
 961  * @ctask: ctask to requeue
 962  *
 963  * LLDs that need to run a ctask from the session workqueue should call
 964  * this. The session lock must be held.
 965  */
 966 void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
 967 {
 968         struct iscsi_conn *conn = ctask->conn;
 969
 970         list_move_tail(&ctask->running, &conn->requeue);
 971         scsi_queue_work(conn->session->host, &conn->xmitwork);
 972 }
 973 EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
 974
 975 /**
 976  * iscsi_data_xmit - xmit any command into the scheduled connection
 977  * @conn: iscsi connection
 978  *
 979  * Notes:
 980  *      The function can return -EAGAIN in which case the caller must
 981  *      re-schedule it again later or recover. '0' return code means
 982  *      successful xmit.
 983  **/
 984 static int iscsi_data_xmit(struct iscsi_conn *conn)
 985 {
 986         int rc = 0;
 987
 988         spin_lock_bh(&conn->session->lock);
 989         if (unlikely(conn->suspend_tx)) {
 990                 debug_scsi("conn %d Tx suspended!\n", conn->id);
 991                 spin_unlock_bh(&conn->session->lock);
 992                 return -ENODATA;
 993         }
 994
 995         if (conn->ctask) {
 996                 rc = iscsi_xmit_ctask(conn);
 997                 if (rc)
 998                         goto again;
 999         }
1000
1001         if (conn->mtask) {
1002                 rc = iscsi_xmit_mtask(conn);
1003                 if (rc)
1004                         goto again;
1005         }
1006
1007         /*
1008          * process mgmt pdus like nops before commands since we should
1009          * only have one nop-out as a ping from us and targets should not
1010          * overflow us with nop-ins
1011          */
1012 check_mgmt:
1013         while (!list_empty(&conn->mgmtqueue)) {
1014                 conn->mtask = list_entry(conn->mgmtqueue.next,
1015                                          struct iscsi_mgmt_task, running);
1016                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1017                         iscsi_free_mgmt_task(conn, conn->mtask);
1018                         conn->mtask = NULL;
1019                         continue;
1020                 }
1021
1022                 iscsi_prep_mtask(conn, conn->mtask);
1023                 list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
1024                 rc = iscsi_xmit_mtask(conn);
1025                 if (rc)
1026                         goto again;
1027         }
1028
1029         /* process pending command queue */
1030         while (!list_empty(&conn->xmitqueue)) {
1031                 if (conn->tmf_state == TMF_QUEUED)
1032                         break;
1033
1034                 conn->ctask = list_entry(conn->xmitqueue.next,
1035                                          struct iscsi_cmd_task, running);
1036                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1037                         fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
1038                         continue;
1039                 }
1040                 if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
1041                         fail_command(conn, conn->ctask, DID_ABORT << 16);
1042                         continue;
1043                 }
1044
1045                 conn->ctask->state = ISCSI_TASK_RUNNING;
1046                 list_move_tail(conn->xmitqueue.next, &conn->run_list);
1047                 rc = iscsi_xmit_ctask(conn);
1048                 if (rc)
1049                         goto again;
1050                 /*
1051                  * we could continuously get new ctask requests so
1052                  * we need to check the mgmt queue for nops that need to
1053                  * be sent to aviod starvation
1054                  */
1055                 if (!list_empty(&conn->mgmtqueue))
1056                         goto check_mgmt;
1057         }
1058
1059         while (!list_empty(&conn->requeue)) {
1060                 if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
1061                         break;
1062
1063                 /*
1064                  * we always do fastlogout - conn stop code will clean up.
1065                  */
1066                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1067                         break;
1068
1069                 conn->ctask = list_entry(conn->requeue.next,
1070                                          struct iscsi_cmd_task, running);
1071                 conn->ctask->state = ISCSI_TASK_RUNNING;
1072                 list_move_tail(conn->requeue.next, &conn->run_list);
1073                 rc = iscsi_xmit_ctask(conn);
1074                 if (rc)
1075                         goto again;
1076                 if (!list_empty(&conn->mgmtqueue))
1077                         goto check_mgmt;
1078         }
1079         spin_unlock_bh(&conn->session->lock);
1080         return -ENODATA;
1081
1082 again:
1083         if (unlikely(conn->suspend_tx))
1084                 rc = -ENODATA;
1085         spin_unlock_bh(&conn->session->lock);
1086         return rc;
1087 }
1088
1089 static void iscsi_xmitworker(struct work_struct *work)
1090 {
1091         struct iscsi_conn *conn =
1092                 container_of(work, struct iscsi_conn, xmitwork);
1093         int rc;
1094         /*
1095          * serialize Xmit worker on a per-connection basis.
1096          */
1097         do {
1098                 rc = iscsi_data_xmit(conn);
1099         } while (rc >= 0 || rc == -EAGAIN);
1100 }
1101
1102 enum {
1103         FAILURE_BAD_HOST = 1,
1104         FAILURE_SESSION_FAILED,
1105         FAILURE_SESSION_FREED,
1106         FAILURE_WINDOW_CLOSED,
1107         FAILURE_OOM,
1108         FAILURE_SESSION_TERMINATE,
1109         FAILURE_SESSION_IN_RECOVERY,
1110         FAILURE_SESSION_RECOVERY_TIMEOUT,
1111         FAILURE_SESSION_LOGGING_OUT,
1112         FAILURE_SESSION_NOT_READY,
1113 };
1114
1115 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
1116 {
1117         struct iscsi_cls_session *cls_session;
1118         struct Scsi_Host *host;
1119         int reason = 0;
1120         struct iscsi_session *session;
1121         struct iscsi_conn *conn;
1122         struct iscsi_cmd_task *ctask = NULL;
1123
1124         sc->scsi_done = done;
1125         sc->result = 0;
1126         sc->SCp.ptr = NULL;
1127
1128         host = sc->device->host;
1129         spin_unlock(host->host_lock);
1130
1131         cls_session = starget_to_session(scsi_target(sc->device));
1132         session = cls_session->dd_data;
1133         spin_lock(&session->lock);
1134
1135         reason = iscsi_session_chkready(cls_session);
1136         if (reason) {
1137                 sc->result = reason;
1138                 goto fault;
1139         }
1140
1141         /*
1142          * ISCSI_STATE_FAILED is a temp. state. The recovery
1143          * code will decide what is best to do with command queued
1144          * during this time
1145          */
1146         if (session->state != ISCSI_STATE_LOGGED_IN &&
1147             session->state != ISCSI_STATE_FAILED) {
1148                 /*
1149                  * to handle the race between when we set the recovery state
1150                  * and block the session we requeue here (commands could
1151                  * be entering our queuecommand while a block is starting
1152                  * up because the block code is not locked)
1153                  */
1154                 switch (session->state) {
1155                 case ISCSI_STATE_IN_RECOVERY:
1156                         reason = FAILURE_SESSION_IN_RECOVERY;
1157                         sc->result = DID_IMM_RETRY << 16;
1158                         break;
1159                 case ISCSI_STATE_LOGGING_OUT:
1160                         reason = FAILURE_SESSION_LOGGING_OUT;
1161                         sc->result = DID_IMM_RETRY << 16;
1162                         break;
1163                 case ISCSI_STATE_RECOVERY_FAILED:
1164                         reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1165                         sc->result = DID_NO_CONNECT << 16;
1166                         break;
1167                 case ISCSI_STATE_TERMINATE:
1168                         reason = FAILURE_SESSION_TERMINATE;
1169                         sc->result = DID_NO_CONNECT << 16;
1170                         break;
1171                 default:
1172                         reason = FAILURE_SESSION_FREED;
1173                         sc->result = DID_NO_CONNECT << 16;
1174                 }
1175                 goto fault;
1176         }
1177
1178         conn = session->leadconn;
1179         if (!conn) {
1180                 reason = FAILURE_SESSION_FREED;
1181                 sc->result = DID_NO_CONNECT << 16;
1182                 goto fault;
1183         }
1184
1185         if (iscsi_check_cmdsn_window_closed(conn)) {
1186                 reason = FAILURE_WINDOW_CLOSED;
1187                 goto reject;
1188         }
1189
1190         if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
1191                          sizeof(void*))) {
1192                 reason = FAILURE_OOM;
1193                 goto reject;
1194         }
1195         session->queued_cmdsn++;
1196
1197         sc->SCp.phase = session->age;
1198         sc->SCp.ptr = (char *)ctask;
1199
1200         atomic_set(&ctask->refcount, 1);
1201         ctask->state = ISCSI_TASK_PENDING;
1202         ctask->conn = conn;
1203         ctask->sc = sc;
1204         INIT_LIST_HEAD(&ctask->running);
1205
1206         list_add_tail(&ctask->running, &conn->xmitqueue);
1207         spin_unlock(&session->lock);
1208
1209         scsi_queue_work(host, &conn->xmitwork);
1210         spin_lock(host->host_lock);
1211         return 0;
1212
1213 reject:
1214         spin_unlock(&session->lock);
1215         debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
1216         spin_lock(host->host_lock);
1217         return SCSI_MLQUEUE_HOST_BUSY;
1218
1219 fault:
1220         spin_unlock(&session->lock);
1221         debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
1222         if (!scsi_bidi_cmnd(sc))
1223                 scsi_set_resid(sc, scsi_bufflen(sc));
1224         else {
1225                 scsi_out(sc)->resid = scsi_out(sc)->length;
1226                 scsi_in(sc)->resid = scsi_in(sc)->length;
1227         }
1228         sc->scsi_done(sc);
1229         spin_lock(host->host_lock);
1230         return 0;
1231 }
1232 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1233
1234 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
1235 {
1236         if (depth > ISCSI_MAX_CMD_PER_LUN)
1237                 depth = ISCSI_MAX_CMD_PER_LUN;
1238         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1239         return sdev->queue_depth;
1240 }
1241 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1242
1243 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
1244 {
1245         struct iscsi_session *session = cls_session->dd_data;
1246
1247         spin_lock_bh(&session->lock);
1248         if (session->state != ISCSI_STATE_LOGGED_IN) {
1249                 session->state = ISCSI_STATE_RECOVERY_FAILED;
1250                 if (session->leadconn)
1251                         wake_up(&session->leadconn->ehwait);
1252         }
1253         spin_unlock_bh(&session->lock);
1254 }
1255 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
1256
1257 int iscsi_eh_host_reset(struct scsi_cmnd *sc)
1258 {
1259         struct iscsi_cls_session *cls_session;
1260         struct iscsi_session *session;
1261         struct iscsi_conn *conn;
1262
1263         cls_session = starget_to_session(scsi_target(sc->device));
1264         session = cls_session->dd_data;
1265         conn = session->leadconn;
1266
1267         mutex_lock(&session->eh_mutex);
1268         spin_lock_bh(&session->lock);
1269         if (session->state == ISCSI_STATE_TERMINATE) {
1270 failed:
1271                 debug_scsi("failing host reset: session terminated "
1272                            "[CID %d age %d]\n", conn->id, session->age);
1273                 spin_unlock_bh(&session->lock);
1274                 mutex_unlock(&session->eh_mutex);
1275                 return FAILED;
1276         }
1277
1278         spin_unlock_bh(&session->lock);
1279         mutex_unlock(&session->eh_mutex);
1280         /*
1281          * we drop the lock here but the leadconn cannot be destoyed while
1282          * we are in the scsi eh
1283          */
1284         iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1285
1286         debug_scsi("iscsi_eh_host_reset wait for relogin\n");
1287         wait_event_interruptible(conn->ehwait,
1288                                  session->state == ISCSI_STATE_TERMINATE ||
1289                                  session->state == ISCSI_STATE_LOGGED_IN ||
1290                                  session->state == ISCSI_STATE_RECOVERY_FAILED);
1291         if (signal_pending(current))
1292                 flush_signals(current);
1293
1294         mutex_lock(&session->eh_mutex);
1295         spin_lock_bh(&session->lock);
1296         if (session->state == ISCSI_STATE_LOGGED_IN)
1297                 iscsi_session_printk(KERN_INFO, session,
1298                                      "host reset succeeded\n");
1299         else
1300                 goto failed;
1301         spin_unlock_bh(&session->lock);
1302         mutex_unlock(&session->eh_mutex);
1303         return SUCCESS;
1304 }
1305 EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
1306
1307 static void iscsi_tmf_timedout(unsigned long data)
1308 {
1309         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1310         struct iscsi_session *session = conn->session;
1311
1312         spin_lock(&session->lock);
1313         if (conn->tmf_state == TMF_QUEUED) {
1314                 conn->tmf_state = TMF_TIMEDOUT;
1315                 debug_scsi("tmf timedout\n");
1316                 /* unblock eh_abort() */
1317                 wake_up(&conn->ehwait);
1318         }
1319         spin_unlock(&session->lock);
1320 }
1321
1322 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1323                                    struct iscsi_tm *hdr, int age,
1324                                    int timeout)
1325 {
1326         struct iscsi_session *session = conn->session;
1327         struct iscsi_mgmt_task *mtask;
1328
1329         mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1330                                       NULL, 0);
1331         if (!mtask) {
1332                 spin_unlock_bh(&session->lock);
1333                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1334                 spin_lock_bh(&session->lock);
1335                 debug_scsi("tmf exec failure\n");
1336                 return -EPERM;
1337         }
1338         conn->tmfcmd_pdus_cnt++;
1339         conn->tmf_timer.expires = timeout * HZ + jiffies;
1340         conn->tmf_timer.function = iscsi_tmf_timedout;
1341         conn->tmf_timer.data = (unsigned long)conn;
1342         add_timer(&conn->tmf_timer);
1343         debug_scsi("tmf set timeout\n");
1344
1345         spin_unlock_bh(&session->lock);
1346         mutex_unlock(&session->eh_mutex);
1347         scsi_queue_work(session->host, &conn->xmitwork);
1348
1349         /*
1350          * block eh thread until:
1351          *
1352          * 1) tmf response
1353          * 2) tmf timeout
1354          * 3) session is terminated or restarted or userspace has
1355          * given up on recovery
1356          */
1357         wait_event_interruptible(conn->ehwait, age != session->age ||
1358                                  session->state != ISCSI_STATE_LOGGED_IN ||
1359                                  conn->tmf_state != TMF_QUEUED);
1360         if (signal_pending(current))
1361                 flush_signals(current);
1362         del_timer_sync(&conn->tmf_timer);
1363
1364         mutex_lock(&session->eh_mutex);
1365         spin_lock_bh(&session->lock);
1366         /* if the session drops it will clean up the mtask */
1367         if (age != session->age ||
1368             session->state != ISCSI_STATE_LOGGED_IN)
1369                 return -ENOTCONN;
1370         return 0;
1371 }
1372
1373 /*
1374  * Fail commands. session lock held and recv side suspended and xmit
1375  * thread flushed
1376  */
1377 static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
1378                               int error)
1379 {
1380         struct iscsi_cmd_task *ctask, *tmp;
1381
1382         if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
1383                 conn->ctask = NULL;
1384
1385         /* flush pending */
1386         list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
1387                 if (lun == ctask->sc->device->lun || lun == -1) {
1388                         debug_scsi("failing pending sc %p itt 0x%x\n",
1389                                    ctask->sc, ctask->itt);
1390                         fail_command(conn, ctask, error << 16);
1391                 }
1392         }
1393
1394         list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
1395                 if (lun == ctask->sc->device->lun || lun == -1) {
1396                         debug_scsi("failing requeued sc %p itt 0x%x\n",
1397                                    ctask->sc, ctask->itt);
1398                         fail_command(conn, ctask, error << 16);
1399                 }
1400         }
1401
1402         /* fail all other running */
1403         list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1404                 if (lun == ctask->sc->device->lun || lun == -1) {
1405                         debug_scsi("failing in progress sc %p itt 0x%x\n",
1406                                    ctask->sc, ctask->itt);
1407                         fail_command(conn, ctask, DID_BUS_BUSY << 16);
1408                 }
1409         }
1410 }
1411
1412 void iscsi_suspend_tx(struct iscsi_conn *conn)
1413 {
1414         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1415         scsi_flush_work(conn->session->host);
1416 }
1417 EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1418
1419 static void iscsi_start_tx(struct iscsi_conn *conn)
1420 {
1421         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1422         scsi_queue_work(conn->session->host, &conn->xmitwork);
1423 }
1424
1425 static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
1426 {
1427         struct iscsi_cls_session *cls_session;
1428         struct iscsi_session *session;
1429         struct iscsi_conn *conn;
1430         enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
1431
1432         cls_session = starget_to_session(scsi_target(scmd->device));
1433         session = cls_session->dd_data;
1434
1435         debug_scsi("scsi cmd %p timedout\n", scmd);
1436
1437         spin_lock(&session->lock);
1438         if (session->state != ISCSI_STATE_LOGGED_IN) {
1439                 /*
1440                  * We are probably in the middle of iscsi recovery so let
1441                  * that complete and handle the error.
1442                  */
1443                 rc = EH_RESET_TIMER;
1444                 goto done;
1445         }
1446
1447         conn = session->leadconn;
1448         if (!conn) {
1449                 /* In the middle of shuting down */
1450                 rc = EH_RESET_TIMER;
1451                 goto done;
1452         }
1453
1454         if (!conn->recv_timeout && !conn->ping_timeout)
1455                 goto done;
1456         /*
1457          * if the ping timedout then we are in the middle of cleaning up
1458          * and can let the iscsi eh handle it
1459          */
1460         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1461                             (conn->ping_timeout * HZ), jiffies))
1462                 rc = EH_RESET_TIMER;
1463         /*
1464          * if we are about to check the transport then give the command
1465          * more time
1466          */
1467         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
1468                            jiffies))
1469                 rc = EH_RESET_TIMER;
1470         /* if in the middle of checking the transport then give us more time */
1471         if (conn->ping_mtask)
1472                 rc = EH_RESET_TIMER;
1473 done:
1474         spin_unlock(&session->lock);
1475         debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
1476         return rc;
1477 }
1478
1479 static void iscsi_check_transport_timeouts(unsigned long data)
1480 {
1481         struct iscsi_conn *conn = (struct iscsi_conn *)data;
1482         struct iscsi_session *session = conn->session;
1483         unsigned long recv_timeout, next_timeout = 0, last_recv;
1484
1485         spin_lock(&session->lock);
1486         if (session->state != ISCSI_STATE_LOGGED_IN)
1487                 goto done;
1488
1489         recv_timeout = conn->recv_timeout;
1490         if (!recv_timeout)
1491                 goto done;
1492
1493         recv_timeout *= HZ;
1494         last_recv = conn->last_recv;
1495         if (conn->ping_mtask &&
1496             time_before_eq(conn->last_ping + (conn->ping_timeout * HZ),
1497                            jiffies)) {
1498                 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
1499                                   "expired, last rx %lu, last ping %lu, "
1500                                   "now %lu\n", conn->ping_timeout, last_recv,
1501                                   conn->last_ping, jiffies);
1502                 spin_unlock(&session->lock);
1503                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1504                 return;
1505         }
1506
1507         if (time_before_eq(last_recv + recv_timeout, jiffies)) {
1508                 /* send a ping to try to provoke some traffic */
1509                 debug_scsi("Sending nopout as ping on conn %p\n", conn);
1510                 iscsi_send_nopout(conn, NULL);
1511                 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
1512         } else
1513                 next_timeout = last_recv + recv_timeout;
1514
1515         debug_scsi("Setting next tmo %lu\n", next_timeout);
1516         mod_timer(&conn->transport_timer, next_timeout);
1517 done:
1518         spin_unlock(&session->lock);
1519 }
1520
1521 static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
1522                                       struct iscsi_tm *hdr)
1523 {
1524         memset(hdr, 0, sizeof(*hdr));
1525         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1526         hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
1527         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1528         memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1529         hdr->rtt = ctask->hdr->itt;
1530         hdr->refcmdsn = ctask->hdr->cmdsn;
1531 }
1532
1533 int iscsi_eh_abort(struct scsi_cmnd *sc)
1534 {
1535         struct iscsi_cls_session *cls_session;
1536         struct iscsi_session *session;
1537         struct iscsi_conn *conn;
1538         struct iscsi_cmd_task *ctask;
1539         struct iscsi_tm *hdr;
1540         int rc, age;
1541
1542         cls_session = starget_to_session(scsi_target(sc->device));
1543         session = cls_session->dd_data;
1544
1545         mutex_lock(&session->eh_mutex);
1546         spin_lock_bh(&session->lock);
1547         /*
1548          * if session was ISCSI_STATE_IN_RECOVERY then we may not have
1549          * got the command.
1550          */
1551         if (!sc->SCp.ptr) {
1552                 debug_scsi("sc never reached iscsi layer or it completed.\n");
1553                 spin_unlock_bh(&session->lock);
1554                 mutex_unlock(&session->eh_mutex);
1555                 return SUCCESS;
1556         }
1557
1558         /*
1559          * If we are not logged in or we have started a new session
1560          * then let the host reset code handle this
1561          */
1562         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
1563             sc->SCp.phase != session->age) {
1564                 spin_unlock_bh(&session->lock);
1565                 mutex_unlock(&session->eh_mutex);
1566                 return FAILED;
1567         }
1568
1569         conn = session->leadconn;
1570         conn->eh_abort_cnt++;
1571         age = session->age;
1572
1573         ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1574         debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1575
1576         /* ctask completed before time out */
1577         if (!ctask->sc) {
1578                 debug_scsi("sc completed while abort in progress\n");
1579                 goto success;
1580         }
1581
1582         if (ctask->state == ISCSI_TASK_PENDING) {
1583                 fail_command(conn, ctask, DID_ABORT << 16);
1584                 goto success;
1585         }
1586
1587         /* only have one tmf outstanding at a time */
1588         if (conn->tmf_state != TMF_INITIAL)
1589                 goto failed;
1590         conn->tmf_state = TMF_QUEUED;
1591
1592         hdr = &conn->tmhdr;
1593         iscsi_prep_abort_task_pdu(ctask, hdr);
1594
1595         if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
1596                 rc = FAILED;
1597                 goto failed;
1598         }
1599
1600         switch (conn->tmf_state) {
1601         case TMF_SUCCESS:
1602                 spin_unlock_bh(&session->lock);
1603                 iscsi_suspend_tx(conn);
1604                 /*
1605                  * clean up task if aborted. grab the recv lock as a writer
1606                  */
1607                 write_lock_bh(conn->recv_lock);
1608                 spin_lock(&session->lock);
1609                 fail_command(conn, ctask, DID_ABORT << 16);
1610                 conn->tmf_state = TMF_INITIAL;
1611                 spin_unlock(&session->lock);
1612                 write_unlock_bh(conn->recv_lock);
1613                 iscsi_start_tx(conn);
1614                 goto success_unlocked;
1615         case TMF_TIMEDOUT:
1616                 spin_unlock_bh(&session->lock);
1617                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1618                 goto failed_unlocked;
1619         case TMF_NOT_FOUND:
1620                 if (!sc->SCp.ptr) {
1621                         conn->tmf_state = TMF_INITIAL;
1622                         /* ctask completed before tmf abort response */
1623                         debug_scsi("sc completed while abort in progress\n");
1624                         goto success;
1625                 }
1626                 /* fall through */
1627         default:
1628                 conn->tmf_state = TMF_INITIAL;
1629                 goto failed;
1630         }
1631
1632 success:
1633         spin_unlock_bh(&session->lock);
1634 success_unlocked:
1635         debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1636         mutex_unlock(&session->eh_mutex);
1637         return SUCCESS;
1638
1639 failed:
1640         spin_unlock_bh(&session->lock);
1641 failed_unlocked:
1642         debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
1643                     ctask ? ctask->itt : 0);
1644         mutex_unlock(&session->eh_mutex);
1645         return FAILED;
1646 }
1647 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1648
1649 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
1650 {
1651         memset(hdr, 0, sizeof(*hdr));
1652         hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
1653         hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
1654         hdr->flags |= ISCSI_FLAG_CMD_FINAL;
1655         int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
1656         hdr->rtt = RESERVED_ITT;
1657 }
1658
1659 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
1660 {
1661         struct iscsi_cls_session *cls_session;
1662         struct iscsi_session *session;
1663         struct iscsi_conn *conn;
1664         struct iscsi_tm *hdr;
1665         int rc = FAILED;
1666
1667         cls_session = starget_to_session(scsi_target(sc->device));
1668         session = cls_session->dd_data;
1669
1670         debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
1671
1672         mutex_lock(&session->eh_mutex);
1673         spin_lock_bh(&session->lock);
1674         /*
1675          * Just check if we are not logged in. We cannot check for
1676          * the phase because the reset could come from a ioctl.
1677          */
1678         if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
1679                 goto unlock;
1680         conn = session->leadconn;
1681
1682         /* only have one tmf outstanding at a time */
1683         if (conn->tmf_state != TMF_INITIAL)
1684                 goto unlock;
1685         conn->tmf_state = TMF_QUEUED;
1686
1687         hdr = &conn->tmhdr;
1688         iscsi_prep_lun_reset_pdu(sc, hdr);
1689
1690         if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
1691                                     session->lu_reset_timeout)) {
1692                 rc = FAILED;
1693                 goto unlock;
1694         }
1695
1696         switch (conn->tmf_state) {
1697         case TMF_SUCCESS:
1698                 break;
1699         case TMF_TIMEDOUT:
1700                 spin_unlock_bh(&session->lock);
1701                 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1702                 goto done;
1703         default:
1704                 conn->tmf_state = TMF_INITIAL;
1705                 goto unlock;
1706         }
1707
1708         rc = SUCCESS;
1709         spin_unlock_bh(&session->lock);
1710
1711         iscsi_suspend_tx(conn);
1712         /* need to grab the recv lock then session lock */
1713         write_lock_bh(conn->recv_lock);
1714         spin_lock(&session->lock);
1715         fail_all_commands(conn, sc->device->lun, DID_ERROR);
1716         conn->tmf_state = TMF_INITIAL;
1717         spin_unlock(&session->lock);
1718         write_unlock_bh(conn->recv_lock);
1719
1720         iscsi_start_tx(conn);
1721         goto done;
1722
1723 unlock:
1724         spin_unlock_bh(&session->lock);
1725 done:
1726         debug_scsi("iscsi_eh_device_reset %s\n",
1727                   rc == SUCCESS ? "SUCCESS" : "FAILED");
1728         mutex_unlock(&session->eh_mutex);
1729         return rc;
1730 }
1731 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
1732
1733 /*
1734  * Pre-allocate a pool of @max items of @item_size. By default, the pool
1735  * should be accessed via kfifo_{get,put} on q->queue.
1736  * Optionally, the caller can obtain the array of object pointers
1737  * by passing in a non-NULL @items pointer
1738  */
1739 int
1740 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
1741 {
1742         int i, num_arrays = 1;
1743
1744         memset(q, 0, sizeof(*q));
1745
1746         q->max = max;
1747
1748         /* If the user passed an items pointer, he wants a copy of
1749          * the array. */
1750         if (items)
1751                 num_arrays++;
1752         q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
1753         if (q->pool == NULL)
1754                 goto enomem;
1755
1756         q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1757                               GFP_KERNEL, NULL);
1758         if (q->queue == ERR_PTR(-ENOMEM))
1759                 goto enomem;
1760
1761         for (i = 0; i < max; i++) {
1762                 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
1763                 if (q->pool[i] == NULL) {
1764                         q->max = i;
1765                         goto enomem;
1766                 }
1767                 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1768         }
1769
1770         if (items) {
1771                 *items = q->pool + max;
1772                 memcpy(*items, q->pool, max * sizeof(void *));
1773         }
1774
1775         return 0;
1776
1777 enomem:
1778         iscsi_pool_free(q);
1779         return -ENOMEM;
1780 }
1781 EXPORT_SYMBOL_GPL(iscsi_pool_init);
1782
1783 void iscsi_pool_free(struct iscsi_pool *q)
1784 {
1785         int i;
1786
1787         for (i = 0; i < q->max; i++)
1788                 kfree(q->pool[i]);
1789         if (q->pool)
1790                 kfree(q->pool);
1791 }
1792 EXPORT_SYMBOL_GPL(iscsi_pool_free);
1793
1794 /**
1795  * iscsi_host_add - add host to system
1796  * @shost: scsi host
1797  * @pdev: parent device
1798  *
1799  * This should be called by partial offload and software iscsi drivers
1800  * to add a host to the system.
1801  */
1802 int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
1803 {
1804         return scsi_add_host(shost, pdev);
1805 }
1806 EXPORT_SYMBOL_GPL(iscsi_host_add);
1807
1808 /**
1809  * iscsi_host_alloc - allocate a host and driver data
1810  * @sht: scsi host template
1811  * @dd_data_size: driver host data size
1812  * @qdepth: default device queue depth
1813  *
1814  * This should be called by partial offload and software iscsi drivers.
1815  * To access the driver specific memory use the iscsi_host_priv() macro.
1816  */
1817 struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
1818                                    int dd_data_size, uint16_t qdepth)
1819 {
1820         struct Scsi_Host *shost;
1821
1822         shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
1823         if (!shost)
1824                 return NULL;
1825         shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
1826
1827         if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
1828                 if (qdepth != 0)
1829                         printk(KERN_ERR "iscsi: invalid queue depth of %d. "
1830                                "Queue depth must be between 1 and %d.\n",
1831                                qdepth, ISCSI_MAX_CMD_PER_LUN);
1832                 qdepth = ISCSI_DEF_CMD_PER_LUN;
1833         }
1834         shost->cmd_per_lun = qdepth;
1835         return shost;
1836 }
1837 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
1838
1839 /**
1840  * iscsi_host_remove - remove host and sessions
1841  * @shost: scsi host
1842  *
1843  * This will also remove any sessions attached to the host, but if userspace
1844  * is managing the session at the same time this will break. TODO: add
1845  * refcounting to the netlink iscsi interface so a rmmod or host hot unplug
1846  * does not remove the memory from under us.
1847  */
1848 void iscsi_host_remove(struct Scsi_Host *shost)
1849 {
1850         iscsi_host_for_each_session(shost, iscsi_session_teardown);
1851         scsi_remove_host(shost);
1852 }
1853 EXPORT_SYMBOL_GPL(iscsi_host_remove);
1854
1855 void iscsi_host_free(struct Scsi_Host *shost)
1856 {
1857         struct iscsi_host *ihost = shost_priv(shost);
1858
1859         kfree(ihost->netdev);
1860         kfree(ihost->hwaddress);
1861         kfree(ihost->initiatorname);
1862         scsi_host_put(shost);
1863 }
1864 EXPORT_SYMBOL_GPL(iscsi_host_free);
1865
1866 /**
1867  * iscsi_session_setup - create iscsi cls session and host and session
1868  * @iscsit: iscsi transport template
1869  * @shost: scsi host
1870  * @cmds_max: session can queue
1871  * @cmd_task_size: LLD ctask private data size
1872  * @mgmt_task_size: LLD mtask private data size
1873  * @initial_cmdsn: initial CmdSN
1874  *
1875  * This can be used by software iscsi_transports that allocate
1876  * a session per scsi host.
1877  */
1878 struct iscsi_cls_session *
1879 iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
1880                     uint16_t cmds_max, int cmd_task_size, int mgmt_task_size,
1881                     uint32_t initial_cmdsn)
1882 {
1883         struct iscsi_session *session;
1884         struct iscsi_cls_session *cls_session;
1885         int cmd_i;
1886
1887         if (!is_power_of_2(cmds_max) || cmds_max >= ISCSI_MGMT_ITT_OFFSET ||
1888             cmds_max < 2) {
1889                 if (cmds_max != 0)
1890                         printk(KERN_ERR "iscsi: invalid can_queue of %d. "
1891                                "can_queue must be a power of 2 and between "
1892                                "2 and %d - setting to %d.\n", cmds_max,
1893                                ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
1894                 cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
1895         }
1896
1897         cls_session = iscsi_alloc_session(shost, iscsit,
1898                                           sizeof(struct iscsi_session));
1899         if (!cls_session)
1900                 return NULL;
1901         session = cls_session->dd_data;
1902         session->cls_session = cls_session;
1903         session->host = shost;
1904         session->state = ISCSI_STATE_FREE;
1905         session->fast_abort = 1;
1906         session->lu_reset_timeout = 15;
1907         session->abort_timeout = 10;
1908         session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1909         session->cmds_max = cmds_max;
1910         session->queued_cmdsn = session->cmdsn = initial_cmdsn;
1911         session->exp_cmdsn = initial_cmdsn + 1;
1912         session->max_cmdsn = initial_cmdsn + 1;
1913         session->max_r2t = 1;
1914         session->tt = iscsit;
1915         mutex_init(&session->eh_mutex);
1916         spin_lock_init(&session->lock);
1917
1918         /* initialize SCSI PDU commands pool */
1919         if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1920                             (void***)&session->cmds,
1921                             cmd_task_size + sizeof(struct iscsi_cmd_task)))
1922                 goto cmdpool_alloc_fail;
1923
1924         /* pre-format cmds pool with ITT */
1925         for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1926                 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1927
1928                 if (cmd_task_size)
1929                         ctask->dd_data = &ctask[1];
1930                 ctask->itt = cmd_i;
1931                 INIT_LIST_HEAD(&ctask->running);
1932         }
1933
1934         /* initialize immediate command pool */
1935         if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1936                            (void***)&session->mgmt_cmds,
1937                            mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1938                 goto mgmtpool_alloc_fail;
1939
1940
1941         /* pre-format immediate cmds pool with ITT */
1942         for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1943                 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1944
1945                 if (mgmt_task_size)
1946                         mtask->dd_data = &mtask[1];
1947                 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1948                 INIT_LIST_HEAD(&mtask->running);
1949         }
1950
1951         if (!try_module_get(iscsit->owner))
1952                 goto module_get_fail;
1953
1954         if (iscsi_add_session(cls_session, 0))
1955                 goto cls_session_fail;
1956         return cls_session;
1957
1958 cls_session_fail:
1959         module_put(iscsit->owner);
1960 module_get_fail:
1961         iscsi_pool_free(&session->mgmtpool);
1962 mgmtpool_alloc_fail:
1963         iscsi_pool_free(&session->cmdpool);
1964 cmdpool_alloc_fail:
1965         iscsi_free_session(cls_session);
1966         return NULL;
1967 }
1968 EXPORT_SYMBOL_GPL(iscsi_session_setup);
1969
1970 /**
1971  * iscsi_session_teardown - destroy session, host, and cls_session
1972  * @cls_session: iscsi session
1973  *
1974  * The driver must have called iscsi_remove_session before
1975  * calling this.
1976  */
1977 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1978 {
1979         struct iscsi_session *session = cls_session->dd_data;
1980         struct module *owner = cls_session->transport->owner;
1981
1982         iscsi_pool_free(&session->mgmtpool);
1983         iscsi_pool_free(&session->cmdpool);
1984
1985         kfree(session->password);
1986         kfree(session->password_in);
1987         kfree(session->username);
1988         kfree(session->username_in);
1989         kfree(session->targetname);
1990
1991         iscsi_destroy_session(cls_session);
1992         module_put(owner);
1993 }
1994 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1995
1996 /**
1997  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1998  * @cls_session: iscsi_cls_session
1999  * @dd_size: private driver data size
2000  * @conn_idx: cid
2001  */
2002 struct iscsi_cls_conn *
2003 iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2004                  uint32_t conn_idx)
2005 {
2006         struct iscsi_session *session = cls_session->dd_data;
2007         struct iscsi_conn *conn;
2008         struct iscsi_cls_conn *cls_conn;
2009         char *data;
2010
2011         cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2012                                      conn_idx);
2013         if (!cls_conn)
2014                 return NULL;
2015         conn = cls_conn->dd_data;
2016         memset(conn, 0, sizeof(*conn) + dd_size);
2017
2018         conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2019         conn->session = session;
2020         conn->cls_conn = cls_conn;
2021         conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2022         conn->id = conn_idx;
2023         conn->exp_statsn = 0;
2024         conn->tmf_state = TMF_INITIAL;
2025
2026         init_timer(&conn->transport_timer);
2027         conn->transport_timer.data = (unsigned long)conn;
2028         conn->transport_timer.function = iscsi_check_transport_timeouts;
2029
2030         INIT_LIST_HEAD(&conn->run_list);
2031         INIT_LIST_HEAD(&conn->mgmt_run_list);
2032         INIT_LIST_HEAD(&conn->mgmtqueue);
2033         INIT_LIST_HEAD(&conn->xmitqueue);
2034         INIT_LIST_HEAD(&conn->requeue);
2035         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2036
2037         /* allocate login_mtask used for the login/text sequences */
2038         spin_lock_bh(&session->lock);
2039         if (!__kfifo_get(session->mgmtpool.queue,
2040                          (void*)&conn->login_mtask,
2041                          sizeof(void*))) {
2042                 spin_unlock_bh(&session->lock);
2043                 goto login_mtask_alloc_fail;
2044         }
2045         spin_unlock_bh(&session->lock);
2046
2047         data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
2048         if (!data)
2049                 goto login_mtask_data_alloc_fail;
2050         conn->login_mtask->data = conn->data = data;
2051
2052         init_timer(&conn->tmf_timer);
2053         init_waitqueue_head(&conn->ehwait);
2054
2055         return cls_conn;
2056
2057 login_mtask_data_alloc_fail:
2058         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2059                     sizeof(void*));
2060 login_mtask_alloc_fail:
2061         iscsi_destroy_conn(cls_conn);
2062         return NULL;
2063 }
2064 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2065
2066 /**
2067  * iscsi_conn_teardown - teardown iscsi connection
2068  * cls_conn: iscsi class connection
2069  *
2070  * TODO: we may need to make this into a two step process
2071  * like scsi-mls remove + put host
2072  */
2073 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2074 {
2075         struct iscsi_conn *conn = cls_conn->dd_data;
2076         struct iscsi_session *session = conn->session;
2077         unsigned long flags;
2078
2079         del_timer_sync(&conn->transport_timer);
2080
2081         spin_lock_bh(&session->lock);
2082         conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2083         if (session->leadconn == conn) {
2084                 /*
2085                  * leading connection? then give up on recovery.
2086                  */
2087                 session->state = ISCSI_STATE_TERMINATE;
2088                 wake_up(&conn->ehwait);
2089         }
2090         spin_unlock_bh(&session->lock);
2091
2092         /*
2093          * Block until all in-progress commands for this connection
2094          * time out or fail.
2095          */
2096         for (;;) {
2097                 spin_lock_irqsave(session->host->host_lock, flags);
2098                 if (!session->host->host_busy) { /* OK for ERL == 0 */
2099                         spin_unlock_irqrestore(session->host->host_lock, flags);
2100                         break;
2101                 }
2102                 spin_unlock_irqrestore(session->host->host_lock, flags);
2103                 msleep_interruptible(500);
2104                 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2105                                   "host_busy %d host_failed %d\n",
2106                                   session->host->host_busy,
2107                                   session->host->host_failed);
2108                 /*
2109                  * force eh_abort() to unblock
2110                  */
2111                 wake_up(&conn->ehwait);
2112         }
2113
2114         /* flush queued up work because we free the connection below */
2115         iscsi_suspend_tx(conn);
2116
2117         spin_lock_bh(&session->lock);
2118         kfree(conn->data);
2119         kfree(conn->persistent_address);
2120         __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2121                     sizeof(void*));
2122         if (session->leadconn == conn)
2123                 session->leadconn = NULL;
2124         spin_unlock_bh(&session->lock);
2125
2126         iscsi_destroy_conn(cls_conn);
2127 }
2128 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2129
2130 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2131 {
2132         struct iscsi_conn *conn = cls_conn->dd_data;
2133         struct iscsi_session *session = conn->session;
2134
2135         if (!session) {
2136                 iscsi_conn_printk(KERN_ERR, conn,
2137                                   "can't start unbound connection\n");
2138                 return -EPERM;
2139         }
2140
2141         if ((session->imm_data_en || !session->initial_r2t_en) &&
2142              session->first_burst > session->max_burst) {
2143                 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2144                                   "first_burst %d max_burst %d\n",
2145                                   session->first_burst, session->max_burst);
2146                 return -EINVAL;
2147         }
2148
2149         if (conn->ping_timeout && !conn->recv_timeout) {
2150                 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2151                                   "zero. Using 5 seconds\n.");
2152                 conn->recv_timeout = 5;
2153         }
2154
2155         if (conn->recv_timeout && !conn->ping_timeout) {
2156                 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2157                                   "zero. Using 5 seconds.\n");
2158                 conn->ping_timeout = 5;
2159         }
2160
2161         spin_lock_bh(&session->lock);
2162         conn->c_stage = ISCSI_CONN_STARTED;
2163         session->state = ISCSI_STATE_LOGGED_IN;
2164         session->queued_cmdsn = session->cmdsn;
2165
2166         conn->last_recv = jiffies;
2167         conn->last_ping = jiffies;
2168         if (conn->recv_timeout && conn->ping_timeout)
2169                 mod_timer(&conn->transport_timer,
2170                           jiffies + (conn->recv_timeout * HZ));
2171
2172         switch(conn->stop_stage) {
2173         case STOP_CONN_RECOVER:
2174                 /*
2175                  * unblock eh_abort() if it is blocked. re-try all
2176                  * commands after successful recovery
2177                  */
2178                 conn->stop_stage = 0;
2179                 conn->tmf_state = TMF_INITIAL;
2180                 session->age++;
2181                 if (session->age == 16)
2182                         session->age = 0;
2183                 break;
2184         case STOP_CONN_TERM:
2185                 conn->stop_stage = 0;
2186                 break;
2187         default:
2188                 break;
2189         }
2190         spin_unlock_bh(&session->lock);
2191
2192         iscsi_unblock_session(session->cls_session);
2193         wake_up(&conn->ehwait);
2194         return 0;
2195 }
2196 EXPORT_SYMBOL_GPL(iscsi_conn_start);
2197
2198 static void
2199 flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
2200 {
2201         struct iscsi_mgmt_task *mtask, *tmp;
2202
2203         /* handle pending */
2204         list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
2205                 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
2206                 iscsi_free_mgmt_task(conn, mtask);
2207         }
2208
2209         /* handle running */
2210         list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
2211                 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
2212                 iscsi_free_mgmt_task(conn, mtask);
2213         }
2214
2215         conn->mtask = NULL;
2216 }
2217
2218 static void iscsi_start_session_recovery(struct iscsi_session *session,
2219                                          struct iscsi_conn *conn, int flag)
2220 {
2221         int old_stop_stage;
2222
2223         del_timer_sync(&conn->transport_timer);
2224
2225         mutex_lock(&session->eh_mutex);
2226         spin_lock_bh(&session->lock);
2227         if (conn->stop_stage == STOP_CONN_TERM) {
2228                 spin_unlock_bh(&session->lock);
2229                 mutex_unlock(&session->eh_mutex);
2230                 return;
2231         }
2232
2233         /*
2234          * The LLD either freed/unset the lock on us, or userspace called
2235          * stop but did not create a proper connection (connection was never
2236          * bound or it was unbound then stop was called).
2237          */
2238         if (!conn->recv_lock) {
2239                 spin_unlock_bh(&session->lock);
2240                 mutex_unlock(&session->eh_mutex);
2241                 return;
2242         }
2243
2244         /*
2245          * When this is called for the in_login state, we only want to clean
2246          * up the login task and connection. We do not need to block and set
2247          * the recovery state again
2248          */
2249         if (flag == STOP_CONN_TERM)
2250                 session->state = ISCSI_STATE_TERMINATE;
2251         else if (conn->stop_stage != STOP_CONN_RECOVER)
2252                 session->state = ISCSI_STATE_IN_RECOVERY;
2253
2254         old_stop_stage = conn->stop_stage;
2255         conn->stop_stage = flag;
2256         conn->c_stage = ISCSI_CONN_STOPPED;
2257         spin_unlock_bh(&session->lock);
2258
2259         iscsi_suspend_tx(conn);
2260
2261         write_lock_bh(conn->recv_lock);
2262         set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2263         write_unlock_bh(conn->recv_lock);
2264
2265         /*
2266          * for connection level recovery we should not calculate
2267          * header digest. conn->hdr_size used for optimization
2268          * in hdr_extract() and will be re-negotiated at
2269          * set_param() time.
2270          */
2271         if (flag == STOP_CONN_RECOVER) {
2272                 conn->hdrdgst_en = 0;
2273                 conn->datadgst_en = 0;
2274                 if (session->state == ISCSI_STATE_IN_RECOVERY &&
2275                     old_stop_stage != STOP_CONN_RECOVER) {
2276                         debug_scsi("blocking session\n");
2277                         iscsi_block_session(session->cls_session);
2278                 }
2279         }
2280
2281         /*
2282          * flush queues.
2283          */
2284         spin_lock_bh(&session->lock);
2285         fail_all_commands(conn, -1,
2286                         STOP_CONN_RECOVER ? DID_BUS_BUSY : DID_ERROR);
2287         flush_control_queues(session, conn);
2288         spin_unlock_bh(&session->lock);
2289         mutex_unlock(&session->eh_mutex);
2290 }
2291
2292 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
2293 {
2294         struct iscsi_conn *conn = cls_conn->dd_data;
2295         struct iscsi_session *session = conn->session;
2296
2297         switch (flag) {
2298         case STOP_CONN_RECOVER:
2299         case STOP_CONN_TERM:
2300                 iscsi_start_session_recovery(session, conn, flag);
2301                 break;
2302         default:
2303                 iscsi_conn_printk(KERN_ERR, conn,
2304                                   "invalid stop flag %d\n", flag);
2305         }
2306 }
2307 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
2308
2309 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
2310                     struct iscsi_cls_conn *cls_conn, int is_leading)
2311 {
2312         struct iscsi_session *session = cls_session->dd_data;
2313         struct iscsi_conn *conn = cls_conn->dd_data;
2314
2315         spin_lock_bh(&session->lock);
2316         if (is_leading)
2317                 session->leadconn = conn;
2318         spin_unlock_bh(&session->lock);
2319
2320         /*
2321          * Unblock xmitworker(), Login Phase will pass through.
2322          */
2323         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2324         clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
2325         return 0;
2326 }
2327 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
2328
2329
2330 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
2331                     enum iscsi_param param, char *buf, int buflen)
2332 {
2333         struct iscsi_conn *conn = cls_conn->dd_data;
2334         struct iscsi_session *session = conn->session;
2335         uint32_t value;
2336
2337         switch(param) {
2338         case ISCSI_PARAM_FAST_ABORT:
2339                 sscanf(buf, "%d", &session->fast_abort);
2340                 break;
2341         case ISCSI_PARAM_ABORT_TMO:
2342                 sscanf(buf, "%d", &session->abort_timeout);
2343                 break;
2344         case ISCSI_PARAM_LU_RESET_TMO:
2345                 sscanf(buf, "%d", &session->lu_reset_timeout);
2346                 break;
2347         case ISCSI_PARAM_PING_TMO:
2348                 sscanf(buf, "%d", &conn->ping_timeout);
2349                 break;
2350         case ISCSI_PARAM_RECV_TMO:
2351                 sscanf(buf, "%d", &conn->recv_timeout);
2352                 break;
2353         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2354                 sscanf(buf, "%d", &conn->max_recv_dlength);
2355                 break;
2356         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2357                 sscanf(buf, "%d", &conn->max_xmit_dlength);
2358                 break;
2359         case ISCSI_PARAM_HDRDGST_EN:
2360                 sscanf(buf, "%d", &conn->hdrdgst_en);
2361                 break;
2362         case ISCSI_PARAM_DATADGST_EN:
2363                 sscanf(buf, "%d", &conn->datadgst_en);
2364                 break;
2365         case ISCSI_PARAM_INITIAL_R2T_EN:
2366                 sscanf(buf, "%d", &session->initial_r2t_en);
2367                 break;
2368         case ISCSI_PARAM_MAX_R2T:
2369                 sscanf(buf, "%d", &session->max_r2t);
2370                 break;
2371         case ISCSI_PARAM_IMM_DATA_EN:
2372                 sscanf(buf, "%d", &session->imm_data_en);
2373                 break;
2374         case ISCSI_PARAM_FIRST_BURST:
2375                 sscanf(buf, "%d", &session->first_burst);
2376                 break;
2377         case ISCSI_PARAM_MAX_BURST:
2378                 sscanf(buf, "%d", &session->max_burst);
2379                 break;
2380         case ISCSI_PARAM_PDU_INORDER_EN:
2381                 sscanf(buf, "%d", &session->pdu_inorder_en);
2382                 break;
2383         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2384                 sscanf(buf, "%d", &session->dataseq_inorder_en);
2385                 break;
2386         case ISCSI_PARAM_ERL:
2387                 sscanf(buf, "%d", &session->erl);
2388                 break;
2389         case ISCSI_PARAM_IFMARKER_EN:
2390                 sscanf(buf, "%d", &value);
2391                 BUG_ON(value);
2392                 break;
2393         case ISCSI_PARAM_OFMARKER_EN:
2394                 sscanf(buf, "%d", &value);
2395                 BUG_ON(value);
2396                 break;
2397         case ISCSI_PARAM_EXP_STATSN:
2398                 sscanf(buf, "%u", &conn->exp_statsn);
2399                 break;
2400         case ISCSI_PARAM_USERNAME:
2401                 kfree(session->username);
2402                 session->username = kstrdup(buf, GFP_KERNEL);
2403                 if (!session->username)
2404                         return -ENOMEM;
2405                 break;
2406         case ISCSI_PARAM_USERNAME_IN:
2407                 kfree(session->username_in);
2408                 session->username_in = kstrdup(buf, GFP_KERNEL);
2409                 if (!session->username_in)
2410                         return -ENOMEM;
2411                 break;
2412         case ISCSI_PARAM_PASSWORD:
2413                 kfree(session->password);
2414                 session->password = kstrdup(buf, GFP_KERNEL);
2415                 if (!session->password)
2416                         return -ENOMEM;
2417                 break;
2418         case ISCSI_PARAM_PASSWORD_IN:
2419                 kfree(session->password_in);
2420                 session->password_in = kstrdup(buf, GFP_KERNEL);
2421                 if (!session->password_in)
2422                         return -ENOMEM;
2423                 break;
2424         case ISCSI_PARAM_TARGET_NAME:
2425                 /* this should not change between logins */
2426                 if (session->targetname)
2427                         break;
2428
2429                 session->targetname = kstrdup(buf, GFP_KERNEL);
2430                 if (!session->targetname)
2431                         return -ENOMEM;
2432                 break;
2433         case ISCSI_PARAM_TPGT:
2434                 sscanf(buf, "%d", &session->tpgt);
2435                 break;
2436         case ISCSI_PARAM_PERSISTENT_PORT:
2437                 sscanf(buf, "%d", &conn->persistent_port);
2438                 break;
2439         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2440                 /*
2441                  * this is the address returned in discovery so it should
2442                  * not change between logins.
2443                  */
2444                 if (conn->persistent_address)
2445                         break;
2446
2447                 conn->persistent_address = kstrdup(buf, GFP_KERNEL);
2448                 if (!conn->persistent_address)
2449                         return -ENOMEM;
2450                 break;
2451         default:
2452                 return -ENOSYS;
2453         }
2454
2455         return 0;
2456 }
2457 EXPORT_SYMBOL_GPL(iscsi_set_param);
2458
2459 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
2460                             enum iscsi_param param, char *buf)
2461 {
2462         struct iscsi_session *session = cls_session->dd_data;
2463         int len;
2464
2465         switch(param) {
2466         case ISCSI_PARAM_FAST_ABORT:
2467                 len = sprintf(buf, "%d\n", session->fast_abort);
2468                 break;
2469         case ISCSI_PARAM_ABORT_TMO:
2470                 len = sprintf(buf, "%d\n", session->abort_timeout);
2471                 break;
2472         case ISCSI_PARAM_LU_RESET_TMO:
2473                 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
2474                 break;
2475         case ISCSI_PARAM_INITIAL_R2T_EN:
2476                 len = sprintf(buf, "%d\n", session->initial_r2t_en);
2477                 break;
2478         case ISCSI_PARAM_MAX_R2T:
2479                 len = sprintf(buf, "%hu\n", session->max_r2t);
2480                 break;
2481         case ISCSI_PARAM_IMM_DATA_EN:
2482                 len = sprintf(buf, "%d\n", session->imm_data_en);
2483                 break;
2484         case ISCSI_PARAM_FIRST_BURST:
2485                 len = sprintf(buf, "%u\n", session->first_burst);
2486                 break;
2487         case ISCSI_PARAM_MAX_BURST:
2488                 len = sprintf(buf, "%u\n", session->max_burst);
2489                 break;
2490         case ISCSI_PARAM_PDU_INORDER_EN:
2491                 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
2492                 break;
2493         case ISCSI_PARAM_DATASEQ_INORDER_EN:
2494                 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
2495                 break;
2496         case ISCSI_PARAM_ERL:
2497                 len = sprintf(buf, "%d\n", session->erl);
2498                 break;
2499         case ISCSI_PARAM_TARGET_NAME:
2500                 len = sprintf(buf, "%s\n", session->targetname);
2501                 break;
2502         case ISCSI_PARAM_TPGT:
2503                 len = sprintf(buf, "%d\n", session->tpgt);
2504                 break;
2505         case ISCSI_PARAM_USERNAME:
2506                 len = sprintf(buf, "%s\n", session->username);
2507                 break;
2508         case ISCSI_PARAM_USERNAME_IN:
2509                 len = sprintf(buf, "%s\n", session->username_in);
2510                 break;
2511         case ISCSI_PARAM_PASSWORD:
2512                 len = sprintf(buf, "%s\n", session->password);
2513                 break;
2514         case ISCSI_PARAM_PASSWORD_IN:
2515                 len = sprintf(buf, "%s\n", session->password_in);
2516                 break;
2517         default:
2518                 return -ENOSYS;
2519         }
2520
2521         return len;
2522 }
2523 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
2524
2525 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
2526                          enum iscsi_param param, char *buf)
2527 {
2528         struct iscsi_conn *conn = cls_conn->dd_data;
2529         int len;
2530
2531         switch(param) {
2532         case ISCSI_PARAM_PING_TMO:
2533                 len = sprintf(buf, "%u\n", conn->ping_timeout);
2534                 break;
2535         case ISCSI_PARAM_RECV_TMO:
2536                 len = sprintf(buf, "%u\n", conn->recv_timeout);
2537                 break;
2538         case ISCSI_PARAM_MAX_RECV_DLENGTH:
2539                 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
2540                 break;
2541         case ISCSI_PARAM_MAX_XMIT_DLENGTH:
2542                 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
2543                 break;
2544         case ISCSI_PARAM_HDRDGST_EN:
2545                 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
2546                 break;
2547         case ISCSI_PARAM_DATADGST_EN:
2548                 len = sprintf(buf, "%d\n", conn->datadgst_en);
2549                 break;
2550         case ISCSI_PARAM_IFMARKER_EN:
2551                 len = sprintf(buf, "%d\n", conn->ifmarker_en);
2552                 break;
2553         case ISCSI_PARAM_OFMARKER_EN:
2554                 len = sprintf(buf, "%d\n", conn->ofmarker_en);
2555                 break;
2556         case ISCSI_PARAM_EXP_STATSN:
2557                 len = sprintf(buf, "%u\n", conn->exp_statsn);
2558                 break;
2559         case ISCSI_PARAM_PERSISTENT_PORT:
2560                 len = sprintf(buf, "%d\n", conn->persistent_port);
2561                 break;
2562         case ISCSI_PARAM_PERSISTENT_ADDRESS:
2563                 len = sprintf(buf, "%s\n", conn->persistent_address);
2564                 break;
2565         default:
2566                 return -ENOSYS;
2567         }
2568
2569         return len;
2570 }
2571 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
2572
2573 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2574                          char *buf)
2575 {
2576         struct iscsi_host *ihost = shost_priv(shost);
2577         int len;
2578
2579         switch (param) {
2580         case ISCSI_HOST_PARAM_NETDEV_NAME:
2581                 if (!ihost->netdev)
2582                         len = sprintf(buf, "%s\n", "default");
2583                 else
2584                         len = sprintf(buf, "%s\n", ihost->netdev);
2585                 break;
2586         case ISCSI_HOST_PARAM_HWADDRESS:
2587                 if (!ihost->hwaddress)
2588                         len = sprintf(buf, "%s\n", "default");
2589                 else
2590                         len = sprintf(buf, "%s\n", ihost->hwaddress);
2591                 break;
2592         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2593                 if (!ihost->initiatorname)
2594                         len = sprintf(buf, "%s\n", "unknown");
2595                 else
2596                         len = sprintf(buf, "%s\n", ihost->initiatorname);
2597                 break;
2598         case ISCSI_HOST_PARAM_IPADDRESS:
2599                 if (!strlen(ihost->local_address))
2600                         len = sprintf(buf, "%s\n", "unknown");
2601                 else
2602                         len = sprintf(buf, "%s\n",
2603                                       ihost->local_address);
2604         default:
2605                 return -ENOSYS;
2606         }
2607
2608         return len;
2609 }
2610 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
2611
2612 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
2613                          char *buf, int buflen)
2614 {
2615         struct iscsi_host *ihost = shost_priv(shost);
2616
2617         switch (param) {
2618         case ISCSI_HOST_PARAM_NETDEV_NAME:
2619                 if (!ihost->netdev)
2620                         ihost->netdev = kstrdup(buf, GFP_KERNEL);
2621                 break;
2622         case ISCSI_HOST_PARAM_HWADDRESS:
2623                 if (!ihost->hwaddress)
2624                         ihost->hwaddress = kstrdup(buf, GFP_KERNEL);
2625                 break;
2626         case ISCSI_HOST_PARAM_INITIATOR_NAME:
2627                 if (!ihost->initiatorname)
2628                         ihost->initiatorname = kstrdup(buf, GFP_KERNEL);
2629                 break;
2630         default:
2631                 return -ENOSYS;
2632         }
2633
2634         return 0;
2635 }
2636 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
2637
2638 MODULE_AUTHOR("Mike Christie");
2639 MODULE_DESCRIPTION("iSCSI library functions");
2640 MODULE_LICENSE("GPL");