git.oblomov.eu Git - linux-2.6/blob - drivers/scsi/libiscsi.c

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