drivers/scsi/libiscsi.c

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