drivers/scsi/libiscsi.c

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