Merge branch 'topic/core-cleanup' into for-linus
[safe/jmp/linux-2.6] / drivers / scsi / libiscsi.c
index b17081b..633e090 100644 (file)
@@ -24,6 +24,8 @@
 #include <linux/types.h>
 #include <linux/kfifo.h>
 #include <linux/delay.h>
+#include <linux/log2.h>
+#include <linux/slab.h>
 #include <asm/unaligned.h>
 #include <net/tcp.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_transport_iscsi.h>
 #include <scsi/libiscsi.h>
 
-struct iscsi_session *
-class_to_transport_session(struct iscsi_cls_session *cls_session)
-{
-       struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
-       return iscsi_hostdata(shost->hostdata);
-}
-EXPORT_SYMBOL_GPL(class_to_transport_session);
+static int iscsi_dbg_lib_conn;
+module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
+                  S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi_conn,
+                "Turn on debugging for connections in libiscsi module. "
+                "Set to 1 to turn on, and zero to turn off. Default is off.");
+
+static int iscsi_dbg_lib_session;
+module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
+                  S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi_session,
+                "Turn on debugging for sessions in libiscsi module. "
+                "Set to 1 to turn on, and zero to turn off. Default is off.");
+
+static int iscsi_dbg_lib_eh;
+module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
+                  S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi_eh,
+                "Turn on debugging for error handling in libiscsi module. "
+                "Set to 1 to turn on, and zero to turn off. Default is off.");
+
+#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...)                 \
+       do {                                                    \
+               if (iscsi_dbg_lib_conn)                         \
+                       iscsi_conn_printk(KERN_INFO, _conn,     \
+                                            "%s " dbg_fmt,     \
+                                            __func__, ##arg);  \
+       } while (0);
+
+#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...)                   \
+       do {                                                            \
+               if (iscsi_dbg_lib_session)                              \
+                       iscsi_session_printk(KERN_INFO, _session,       \
+                                            "%s " dbg_fmt,             \
+                                            __func__, ##arg);          \
+       } while (0);
+
+#define ISCSI_DBG_EH(_session, dbg_fmt, arg...)                                \
+       do {                                                            \
+               if (iscsi_dbg_lib_eh)                                   \
+                       iscsi_session_printk(KERN_INFO, _session,       \
+                                            "%s " dbg_fmt,             \
+                                            __func__, ##arg);          \
+       } while (0);
 
 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
 #define SNA32_CHECK 2147483648UL
@@ -61,12 +100,19 @@ static int iscsi_sna_lte(u32 n1, u32 n2)
                            (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
 }
 
-void
-iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
+inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
 {
-       uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
-       uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
+       struct Scsi_Host *shost = conn->session->host;
+       struct iscsi_host *ihost = shost_priv(shost);
+
+       if (ihost->workq)
+               queue_work(ihost->workq, &conn->xmitwork);
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
 
+static void __iscsi_update_cmdsn(struct iscsi_session *session,
+                                uint32_t exp_cmdsn, uint32_t max_cmdsn)
+{
        /*
         * standard specifies this check for when to update expected and
         * max sequence numbers
@@ -85,93 +131,290 @@ iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
                 * if the window closed with IO queued, then kick the
                 * xmit thread
                 */
-               if (!list_empty(&session->leadconn->xmitqueue) ||
+               if (!list_empty(&session->leadconn->cmdqueue) ||
                    !list_empty(&session->leadconn->mgmtqueue))
-                       scsi_queue_work(session->host,
-                                       &session->leadconn->xmitwork);
+                       iscsi_conn_queue_work(session->leadconn);
        }
 }
+
+void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
+{
+       __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
+                            be32_to_cpu(hdr->max_cmdsn));
+}
 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
 
-void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
-                                  struct iscsi_data *hdr)
+/**
+ * iscsi_prep_data_out_pdu - initialize Data-Out
+ * @task: scsi command task
+ * @r2t: R2T info
+ * @hdr: iscsi data in pdu
+ *
+ * Notes:
+ *     Initialize Data-Out within this R2T sequence and finds
+ *     proper data_offset within this SCSI command.
+ *
+ *     This function is called with connection lock taken.
+ **/
+void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
+                          struct iscsi_data *hdr)
 {
-       struct iscsi_conn *conn = ctask->conn;
+       struct iscsi_conn *conn = task->conn;
+       unsigned int left = r2t->data_length - r2t->sent;
+
+       task->hdr_len = sizeof(struct iscsi_data);
 
        memset(hdr, 0, sizeof(struct iscsi_data));
-       hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
-       hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
-       ctask->unsol_datasn++;
+       hdr->ttt = r2t->ttt;
+       hdr->datasn = cpu_to_be32(r2t->datasn);
+       r2t->datasn++;
        hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
-       memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
-
-       hdr->itt = ctask->hdr->itt;
-       hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
-       hdr->offset = cpu_to_be32(ctask->unsol_offset);
-
-       if (ctask->unsol_count > conn->max_xmit_dlength) {
+       memcpy(hdr->lun, task->lun, sizeof(hdr->lun));
+       hdr->itt = task->hdr_itt;
+       hdr->exp_statsn = r2t->exp_statsn;
+       hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
+       if (left > conn->max_xmit_dlength) {
                hton24(hdr->dlength, conn->max_xmit_dlength);
-               ctask->data_count = conn->max_xmit_dlength;
-               ctask->unsol_offset += ctask->data_count;
+               r2t->data_count = conn->max_xmit_dlength;
                hdr->flags = 0;
        } else {
-               hton24(hdr->dlength, ctask->unsol_count);
-               ctask->data_count = ctask->unsol_count;
+               hton24(hdr->dlength, left);
+               r2t->data_count = left;
                hdr->flags = ISCSI_FLAG_CMD_FINAL;
        }
+       conn->dataout_pdus_cnt++;
 }
-EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
+EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
 
-static int iscsi_add_hdr(struct iscsi_cmd_task *ctask, unsigned len)
+static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
 {
-       unsigned exp_len = ctask->hdr_len + len;
+       unsigned exp_len = task->hdr_len + len;
 
-       if (exp_len > ctask->hdr_max) {
+       if (exp_len > task->hdr_max) {
                WARN_ON(1);
                return -EINVAL;
        }
 
        WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
-       ctask->hdr_len = exp_len;
+       task->hdr_len = exp_len;
+       return 0;
+}
+
+/*
+ * make an extended cdb AHS
+ */
+static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
+{
+       struct scsi_cmnd *cmd = task->sc;
+       unsigned rlen, pad_len;
+       unsigned short ahslength;
+       struct iscsi_ecdb_ahdr *ecdb_ahdr;
+       int rc;
+
+       ecdb_ahdr = iscsi_next_hdr(task);
+       rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
+
+       BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
+       ahslength = rlen + sizeof(ecdb_ahdr->reserved);
+
+       pad_len = iscsi_padding(rlen);
+
+       rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
+                          sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
+       if (rc)
+               return rc;
+
+       if (pad_len)
+               memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
+
+       ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
+       ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
+       ecdb_ahdr->reserved = 0;
+       memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
+
+       ISCSI_DBG_SESSION(task->conn->session,
+                         "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
+                         "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
+                         "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
+                         task->hdr_len);
+       return 0;
+}
+
+static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
+{
+       struct scsi_cmnd *sc = task->sc;
+       struct iscsi_rlength_ahdr *rlen_ahdr;
+       int rc;
+
+       rlen_ahdr = iscsi_next_hdr(task);
+       rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
+       if (rc)
+               return rc;
+
+       rlen_ahdr->ahslength =
+               cpu_to_be16(sizeof(rlen_ahdr->read_length) +
+                                                 sizeof(rlen_ahdr->reserved));
+       rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
+       rlen_ahdr->reserved = 0;
+       rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
+
+       ISCSI_DBG_SESSION(task->conn->session,
+                         "bidi-in rlen_ahdr->read_length(%d) "
+                         "rlen_ahdr->ahslength(%d)\n",
+                         be32_to_cpu(rlen_ahdr->read_length),
+                         be16_to_cpu(rlen_ahdr->ahslength));
+       return 0;
+}
+
+/**
+ * iscsi_check_tmf_restrictions - check if a task is affected by TMF
+ * @task: iscsi task
+ * @opcode: opcode to check for
+ *
+ * During TMF a task has to be checked if it's affected.
+ * All unrelated I/O can be passed through, but I/O to the
+ * affected LUN should be restricted.
+ * If 'fast_abort' is set we won't be sending any I/O to the
+ * affected LUN.
+ * Otherwise the target is waiting for all TTTs to be completed,
+ * so we have to send all outstanding Data-Out PDUs to the target.
+ */
+static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
+{
+       struct iscsi_conn *conn = task->conn;
+       struct iscsi_tm *tmf = &conn->tmhdr;
+       unsigned int hdr_lun;
+
+       if (conn->tmf_state == TMF_INITIAL)
+               return 0;
+
+       if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
+               return 0;
+
+       switch (ISCSI_TM_FUNC_VALUE(tmf)) {
+       case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
+               /*
+                * Allow PDUs for unrelated LUNs
+                */
+               hdr_lun = scsilun_to_int((struct scsi_lun *)tmf->lun);
+               if (hdr_lun != task->sc->device->lun)
+                       return 0;
+               /* fall through */
+       case ISCSI_TM_FUNC_TARGET_WARM_RESET:
+               /*
+                * Fail all SCSI cmd PDUs
+                */
+               if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
+                       iscsi_conn_printk(KERN_INFO, conn,
+                                         "task [op %x/%x itt "
+                                         "0x%x/0x%x] "
+                                         "rejected.\n",
+                                         task->hdr->opcode, opcode,
+                                         task->itt, task->hdr_itt);
+                       return -EACCES;
+               }
+               /*
+                * And also all data-out PDUs in response to R2T
+                * if fast_abort is set.
+                */
+               if (conn->session->fast_abort) {
+                       iscsi_conn_printk(KERN_INFO, conn,
+                                         "task [op %x/%x itt "
+                                         "0x%x/0x%x] fast abort.\n",
+                                         task->hdr->opcode, opcode,
+                                         task->itt, task->hdr_itt);
+                       return -EACCES;
+               }
+               break;
+       case ISCSI_TM_FUNC_ABORT_TASK:
+               /*
+                * the caller has already checked if the task
+                * they want to abort was in the pending queue so if
+                * we are here the cmd pdu has gone out already, and
+                * we will only hit this for data-outs
+                */
+               if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
+                   task->hdr_itt == tmf->rtt) {
+                       ISCSI_DBG_SESSION(conn->session,
+                                         "Preventing task %x/%x from sending "
+                                         "data-out due to abort task in "
+                                         "progress\n", task->itt,
+                                         task->hdr_itt);
+                       return -EACCES;
+               }
+               break;
+       }
+
        return 0;
 }
 
 /**
  * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
- * @ctask: iscsi cmd task
+ * @task: iscsi task
  *
  * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
  * fields like dlength or final based on how much data it sends
  */
-static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
+static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 {
-       struct iscsi_conn *conn = ctask->conn;
+       struct iscsi_conn *conn = task->conn;
        struct iscsi_session *session = conn->session;
-       struct iscsi_cmd *hdr = ctask->hdr;
-       struct scsi_cmnd *sc = ctask->sc;
-       unsigned hdrlength;
+       struct scsi_cmnd *sc = task->sc;
+       struct iscsi_cmd *hdr;
+       unsigned hdrlength, cmd_len;
+       itt_t itt;
        int rc;
 
-       ctask->hdr_len = 0;
-       rc = iscsi_add_hdr(ctask, sizeof(*hdr));
+       rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
+       if (rc)
+               return rc;
+
+       if (conn->session->tt->alloc_pdu) {
+               rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
+               if (rc)
+                       return rc;
+       }
+       hdr = (struct iscsi_cmd *) task->hdr;
+       itt = hdr->itt;
+       memset(hdr, 0, sizeof(*hdr));
+
+       if (session->tt->parse_pdu_itt)
+               hdr->itt = task->hdr_itt = itt;
+       else
+               hdr->itt = task->hdr_itt = build_itt(task->itt,
+                                                    task->conn->session->age);
+       task->hdr_len = 0;
+       rc = iscsi_add_hdr(task, sizeof(*hdr));
        if (rc)
                return rc;
-        hdr->opcode = ISCSI_OP_SCSI_CMD;
-        hdr->flags = ISCSI_ATTR_SIMPLE;
-        int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
-        hdr->itt = build_itt(ctask->itt, conn->id, session->age);
-        hdr->data_length = cpu_to_be32(scsi_bufflen(sc));
-        hdr->cmdsn = cpu_to_be32(session->cmdsn);
-        session->cmdsn++;
-        hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
-        memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
-       if (sc->cmd_len < MAX_COMMAND_SIZE)
-               memset(&hdr->cdb[sc->cmd_len], 0,
-                       MAX_COMMAND_SIZE - sc->cmd_len);
-
-       ctask->data_count = 0;
-       ctask->imm_count = 0;
+       hdr->opcode = ISCSI_OP_SCSI_CMD;
+       hdr->flags = ISCSI_ATTR_SIMPLE;
+       int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
+       memcpy(task->lun, hdr->lun, sizeof(task->lun));
+       hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
+       cmd_len = sc->cmd_len;
+       if (cmd_len < ISCSI_CDB_SIZE)
+               memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
+       else if (cmd_len > ISCSI_CDB_SIZE) {
+               rc = iscsi_prep_ecdb_ahs(task);
+               if (rc)
+                       return rc;
+               cmd_len = ISCSI_CDB_SIZE;
+       }
+       memcpy(hdr->cdb, sc->cmnd, cmd_len);
+
+       task->imm_count = 0;
+       if (scsi_bidi_cmnd(sc)) {
+               hdr->flags |= ISCSI_FLAG_CMD_READ;
+               rc = iscsi_prep_bidi_ahs(task);
+               if (rc)
+                       return rc;
+       }
        if (sc->sc_data_direction == DMA_TO_DEVICE) {
+               unsigned out_len = scsi_out(sc)->length;
+               struct iscsi_r2t_info *r2t = &task->unsol_r2t;
+
+               hdr->data_length = cpu_to_be32(out_len);
                hdr->flags |= ISCSI_FLAG_CMD_WRITE;
                /*
                 * Write counters:
@@ -183,182 +426,375 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
                 *                      without R2T ack right after
                 *                      immediate data
                 *
-                *      r2t_data_count  bytes to be sent via R2T ack's
+                *      r2t data_length bytes to be sent via R2T ack's
                 *
                 *      pad_count       bytes to be sent as zero-padding
                 */
-               ctask->unsol_count = 0;
-               ctask->unsol_offset = 0;
-               ctask->unsol_datasn = 0;
+               memset(r2t, 0, sizeof(*r2t));
 
                if (session->imm_data_en) {
-                       if (scsi_bufflen(sc) >= session->first_burst)
-                               ctask->imm_count = min(session->first_burst,
+                       if (out_len >= session->first_burst)
+                               task->imm_count = min(session->first_burst,
                                                        conn->max_xmit_dlength);
                        else
-                               ctask->imm_count = min(scsi_bufflen(sc),
+                               task->imm_count = min(out_len,
                                                        conn->max_xmit_dlength);
-                       hton24(ctask->hdr->dlength, ctask->imm_count);
+                       hton24(hdr->dlength, task->imm_count);
                } else
-                       zero_data(ctask->hdr->dlength);
+                       zero_data(hdr->dlength);
 
                if (!session->initial_r2t_en) {
-                       ctask->unsol_count = min((session->first_burst),
-                               (scsi_bufflen(sc))) - ctask->imm_count;
-                       ctask->unsol_offset = ctask->imm_count;
+                       r2t->data_length = min(session->first_burst, out_len) -
+                                              task->imm_count;
+                       r2t->data_offset = task->imm_count;
+                       r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
+                       r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
                }
 
-               if (!ctask->unsol_count)
+               if (!task->unsol_r2t.data_length)
                        /* No unsolicit Data-Out's */
-                       ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+                       hdr->flags |= ISCSI_FLAG_CMD_FINAL;
        } else {
                hdr->flags |= ISCSI_FLAG_CMD_FINAL;
                zero_data(hdr->dlength);
+               hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
 
                if (sc->sc_data_direction == DMA_FROM_DEVICE)
                        hdr->flags |= ISCSI_FLAG_CMD_READ;
        }
 
        /* calculate size of additional header segments (AHSs) */
-       hdrlength = ctask->hdr_len - sizeof(*hdr);
+       hdrlength = task->hdr_len - sizeof(*hdr);
 
        WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
        hdrlength /= ISCSI_PAD_LEN;
 
        WARN_ON(hdrlength >= 256);
        hdr->hlength = hdrlength & 0xFF;
+       hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
 
-       conn->scsicmd_pdus_cnt++;
+       if (session->tt->init_task && session->tt->init_task(task))
+               return -EIO;
+
+       task->state = ISCSI_TASK_RUNNING;
+       session->cmdsn++;
 
-        debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
-               "cmdsn %d win %d]\n",
-                sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
-               conn->id, sc, sc->cmnd[0], ctask->itt, scsi_bufflen(sc),
-                session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
+       conn->scsicmd_pdus_cnt++;
+       ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
+                         "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
+                         scsi_bidi_cmnd(sc) ? "bidirectional" :
+                         sc->sc_data_direction == DMA_TO_DEVICE ?
+                         "write" : "read", conn->id, sc, sc->cmnd[0],
+                         task->itt, scsi_bufflen(sc),
+                         scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
+                         session->cmdsn,
+                         session->max_cmdsn - session->exp_cmdsn + 1);
        return 0;
 }
 
 /**
- * iscsi_complete_command - return command back to scsi-ml
- * @ctask: iscsi cmd task
+ * iscsi_free_task - free a task
+ * @task: iscsi cmd task
  *
  * Must be called with session lock.
- * This function returns the scsi command to scsi-ml and returns
- * the cmd task to the pool of available cmd tasks.
+ * This function returns the scsi command to scsi-ml or cleans
+ * up mgmt tasks then returns the task to the pool.
  */
-static void iscsi_complete_command(struct iscsi_cmd_task *ctask)
+static void iscsi_free_task(struct iscsi_task *task)
 {
-       struct iscsi_session *session = ctask->conn->session;
-       struct scsi_cmnd *sc = ctask->sc;
+       struct iscsi_conn *conn = task->conn;
+       struct iscsi_session *session = conn->session;
+       struct scsi_cmnd *sc = task->sc;
 
-       ctask->state = ISCSI_TASK_COMPLETED;
-       ctask->sc = NULL;
-       /* SCSI eh reuses commands to verify us */
-       sc->SCp.ptr = NULL;
-       list_del_init(&ctask->running);
-       __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
-       sc->scsi_done(sc);
+       ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
+                         task->itt, task->state, task->sc);
+
+       session->tt->cleanup_task(task);
+       task->state = ISCSI_TASK_FREE;
+       task->sc = NULL;
+       /*
+        * login task is preallocated so do not free
+        */
+       if (conn->login_task == task)
+               return;
+
+       kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
+
+       if (sc) {
+               task->sc = NULL;
+               /* SCSI eh reuses commands to verify us */
+               sc->SCp.ptr = NULL;
+               /*
+                * queue command may call this to free the task, but
+                * not have setup the sc callback
+                */
+               if (sc->scsi_done)
+                       sc->scsi_done(sc);
+       }
+}
+
+void __iscsi_get_task(struct iscsi_task *task)
+{
+       atomic_inc(&task->refcount);
+}
+EXPORT_SYMBOL_GPL(__iscsi_get_task);
+
+static void __iscsi_put_task(struct iscsi_task *task)
+{
+       if (atomic_dec_and_test(&task->refcount))
+               iscsi_free_task(task);
+}
+
+void iscsi_put_task(struct iscsi_task *task)
+{
+       struct iscsi_session *session = task->conn->session;
+
+       spin_lock_bh(&session->lock);
+       __iscsi_put_task(task);
+       spin_unlock_bh(&session->lock);
 }
+EXPORT_SYMBOL_GPL(iscsi_put_task);
 
-static void __iscsi_get_ctask(struct iscsi_cmd_task *ctask)
+/**
+ * iscsi_complete_task - finish a task
+ * @task: iscsi cmd task
+ * @state: state to complete task with
+ *
+ * Must be called with session lock.
+ */
+static void iscsi_complete_task(struct iscsi_task *task, int state)
 {
-       atomic_inc(&ctask->refcount);
+       struct iscsi_conn *conn = task->conn;
+
+       ISCSI_DBG_SESSION(conn->session,
+                         "complete task itt 0x%x state %d sc %p\n",
+                         task->itt, task->state, task->sc);
+       if (task->state == ISCSI_TASK_COMPLETED ||
+           task->state == ISCSI_TASK_ABRT_TMF ||
+           task->state == ISCSI_TASK_ABRT_SESS_RECOV)
+               return;
+       WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
+       task->state = state;
+
+       if (!list_empty(&task->running))
+               list_del_init(&task->running);
+
+       if (conn->task == task)
+               conn->task = NULL;
+
+       if (conn->ping_task == task)
+               conn->ping_task = NULL;
+
+       /* release get from queueing */
+       __iscsi_put_task(task);
 }
 
-static void __iscsi_put_ctask(struct iscsi_cmd_task *ctask)
+/**
+ * iscsi_complete_scsi_task - finish scsi task normally
+ * @task: iscsi task for scsi cmd
+ * @exp_cmdsn: expected cmd sn in cpu format
+ * @max_cmdsn: max cmd sn in cpu format
+ *
+ * This is used when drivers do not need or cannot perform
+ * lower level pdu processing.
+ *
+ * Called with session lock
+ */
+void iscsi_complete_scsi_task(struct iscsi_task *task,
+                             uint32_t exp_cmdsn, uint32_t max_cmdsn)
 {
-       if (atomic_dec_and_test(&ctask->refcount))
-               iscsi_complete_command(ctask);
+       struct iscsi_conn *conn = task->conn;
+
+       ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
+
+       conn->last_recv = jiffies;
+       __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 }
+EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
+
 
 /*
- * session lock must be held
+ * session lock must be held and if not called for a task that is
+ * still pending or from the xmit thread, then xmit thread must
+ * be suspended.
  */
-static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
-                        int err)
+static void fail_scsi_task(struct iscsi_task *task, int err)
 {
+       struct iscsi_conn *conn = task->conn;
        struct scsi_cmnd *sc;
+       int state;
 
-       sc = ctask->sc;
+       /*
+        * if a command completes and we get a successful tmf response
+        * we will hit this because the scsi eh abort code does not take
+        * a ref to the task.
+        */
+       sc = task->sc;
        if (!sc)
                return;
 
-       if (ctask->state == ISCSI_TASK_PENDING)
+       if (task->state == ISCSI_TASK_PENDING) {
                /*
                 * cmd never made it to the xmit thread, so we should not count
                 * the cmd in the sequencing
                 */
                conn->session->queued_cmdsn--;
+               /* it was never sent so just complete like normal */
+               state = ISCSI_TASK_COMPLETED;
+       } else if (err == DID_TRANSPORT_DISRUPTED)
+               state = ISCSI_TASK_ABRT_SESS_RECOV;
        else
-               conn->session->tt->cleanup_cmd_task(conn, ctask);
+               state = ISCSI_TASK_ABRT_TMF;
+
+       sc->result = err << 16;
+       if (!scsi_bidi_cmnd(sc))
+               scsi_set_resid(sc, scsi_bufflen(sc));
+       else {
+               scsi_out(sc)->resid = scsi_out(sc)->length;
+               scsi_in(sc)->resid = scsi_in(sc)->length;
+       }
 
-       sc->result = err;
-       scsi_set_resid(sc, scsi_bufflen(sc));
-       if (conn->ctask == ctask)
-               conn->ctask = NULL;
-       /* release ref from queuecommand */
-       __iscsi_put_ctask(ctask);
+       iscsi_complete_task(task, state);
 }
 
-/**
- * iscsi_free_mgmt_task - return mgmt task back to pool
- * @conn: iscsi connection
- * @mtask: mtask
- *
- * Must be called with session lock.
- */
-void iscsi_free_mgmt_task(struct iscsi_conn *conn,
-                         struct iscsi_mgmt_task *mtask)
+static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
+                               struct iscsi_task *task)
 {
-       list_del_init(&mtask->running);
-       if (conn->login_mtask == mtask)
-               return;
+       struct iscsi_session *session = conn->session;
+       struct iscsi_hdr *hdr = task->hdr;
+       struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
+       uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
+
+       if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
+               return -ENOTCONN;
+
+       if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
+               nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
+       /*
+        * pre-format CmdSN for outgoing PDU.
+        */
+       nop->cmdsn = cpu_to_be32(session->cmdsn);
+       if (hdr->itt != RESERVED_ITT) {
+               /*
+                * TODO: We always use immediate for normal session pdus.
+                * If we start to send tmfs or nops as non-immediate then
+                * we should start checking the cmdsn numbers for mgmt tasks.
+                *
+                * During discovery sessions iscsid sends TEXT as non immediate,
+                * but we always only send one PDU at a time.
+                */
+               if (conn->c_stage == ISCSI_CONN_STARTED &&
+                   !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
+                       session->queued_cmdsn++;
+                       session->cmdsn++;
+               }
+       }
+
+       if (session->tt->init_task && session->tt->init_task(task))
+               return -EIO;
+
+       if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
+               session->state = ISCSI_STATE_LOGGING_OUT;
 
-       if (conn->ping_mtask == mtask)
-               conn->ping_mtask = NULL;
-       __kfifo_put(conn->session->mgmtpool.queue,
-                   (void*)&mtask, sizeof(void*));
+       task->state = ISCSI_TASK_RUNNING;
+       ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
+                         "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
+                         hdr->itt, task->data_count);
+       return 0;
 }
-EXPORT_SYMBOL_GPL(iscsi_free_mgmt_task);
 
-static struct iscsi_mgmt_task *
+static struct iscsi_task *
 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                      char *data, uint32_t data_size)
 {
        struct iscsi_session *session = conn->session;
-       struct iscsi_mgmt_task *mtask;
+       struct iscsi_host *ihost = shost_priv(session->host);
+       uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
+       struct iscsi_task *task;
+       itt_t itt;
 
        if (session->state == ISCSI_STATE_TERMINATE)
                return NULL;
 
-       if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
-           hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
+       if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
                /*
                 * Login and Text are sent serially, in
                 * request-followed-by-response sequence.
-                * Same mtask can be used. Same ITT must be used.
-                * Note that login_mtask is preallocated at conn_create().
+                * Same task can be used. Same ITT must be used.
+                * Note that login_task is preallocated at conn_create().
                 */
-               mtask = conn->login_mtask;
-       else {
+               if (conn->login_task->state != ISCSI_TASK_FREE) {
+                       iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
+                                         "progress. Cannot start new task.\n");
+                       return NULL;
+               }
+
+               task = conn->login_task;
+       } else {
+               if (session->state != ISCSI_STATE_LOGGED_IN)
+                       return NULL;
+
                BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
                BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 
-               if (!__kfifo_get(session->mgmtpool.queue,
-                                (void*)&mtask, sizeof(void*)))
+               if (!kfifo_out(&session->cmdpool.queue,
+                                (void*)&task, sizeof(void*)))
                        return NULL;
        }
+       /*
+        * released in complete pdu for task we expect a response for, and
+        * released by the lld when it has transmitted the task for
+        * pdus we do not expect a response for.
+        */
+       atomic_set(&task->refcount, 1);
+       task->conn = conn;
+       task->sc = NULL;
+       INIT_LIST_HEAD(&task->running);
+       task->state = ISCSI_TASK_PENDING;
 
        if (data_size) {
-               memcpy(mtask->data, data, data_size);
-               mtask->data_count = data_size;
+               memcpy(task->data, data, data_size);
+               task->data_count = data_size;
        } else
-               mtask->data_count = 0;
+               task->data_count = 0;
+
+       if (conn->session->tt->alloc_pdu) {
+               if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
+                       iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
+                                        "pdu for mgmt task.\n");
+                       goto free_task;
+               }
+       }
+
+       itt = task->hdr->itt;
+       task->hdr_len = sizeof(struct iscsi_hdr);
+       memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
+
+       if (hdr->itt != RESERVED_ITT) {
+               if (session->tt->parse_pdu_itt)
+                       task->hdr->itt = itt;
+               else
+                       task->hdr->itt = build_itt(task->itt,
+                                                  task->conn->session->age);
+       }
+
+       if (!ihost->workq) {
+               if (iscsi_prep_mgmt_task(conn, task))
+                       goto free_task;
 
-       memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
-       INIT_LIST_HEAD(&mtask->running);
-       list_add_tail(&mtask->running, &conn->mgmtqueue);
-       return mtask;
+               if (session->tt->xmit_task(task))
+                       goto free_task;
+       } else {
+               list_add_tail(&task->running, &conn->mgmtqueue);
+               iscsi_conn_queue_work(conn);
+       }
+
+       return task;
+
+free_task:
+       __iscsi_put_task(task);
+       return NULL;
 }
 
 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
@@ -372,7 +808,6 @@ int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
        if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
                err = -EPERM;
        spin_unlock_bh(&session->lock);
-       scsi_queue_work(session->host, &conn->xmitwork);
        return err;
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
@@ -381,7 +816,7 @@ EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
  * iscsi_cmd_rsp - SCSI Command Response processing
  * @conn: iscsi connection
  * @hdr: iscsi header
- * @ctask: scsi command task
+ * @task: scsi command task
  * @data: cmd data buffer
  * @datalen: len of buffer
  *
@@ -389,12 +824,12 @@ EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
  * then completes the command and task.
  **/
 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
-                              struct iscsi_cmd_task *ctask, char *data,
+                              struct iscsi_task *task, char *data,
                               int datalen)
 {
        struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
        struct iscsi_session *session = conn->session;
-       struct scsi_cmnd *sc = ctask->sc;
+       struct scsi_cmnd *sc = task->sc;
 
        iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
        conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
@@ -411,20 +846,34 @@ static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 
                if (datalen < 2) {
 invalid_datalen:
-                       printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
-                              "invalid data buffer size of %d\n", datalen);
+                       iscsi_conn_printk(KERN_ERR,  conn,
+                                        "Got CHECK_CONDITION but invalid data "
+                                        "buffer size of %d\n", datalen);
                        sc->result = DID_BAD_TARGET << 16;
                        goto out;
                }
 
-               senselen = be16_to_cpu(get_unaligned((__be16 *) data));
+               senselen = get_unaligned_be16(data);
                if (datalen < senselen)
                        goto invalid_datalen;
 
                memcpy(sc->sense_buffer, data + 2,
                       min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
-               debug_scsi("copied %d bytes of sense\n",
-                          min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
+               ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
+                                 min_t(uint16_t, senselen,
+                                 SCSI_SENSE_BUFFERSIZE));
+       }
+
+       if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
+                          ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
+               int res_count = be32_to_cpu(rhdr->bi_residual_count);
+
+               if (scsi_bidi_cmnd(sc) && res_count > 0 &&
+                               (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
+                                res_count <= scsi_in(sc)->length))
+                       scsi_in(sc)->resid = res_count;
+               else
+                       sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
        }
 
        if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
@@ -434,19 +883,54 @@ invalid_datalen:
                if (res_count > 0 &&
                    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
                     res_count <= scsi_bufflen(sc)))
+                       /* write side for bidi or uni-io set_resid */
                        scsi_set_resid(sc, res_count);
                else
                        sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
-       } else if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
-                                 ISCSI_FLAG_CMD_BIDI_OVERFLOW))
-               sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
-
+       }
 out:
-       debug_scsi("done [sc %lx res %d itt 0x%x]\n",
-                  (long)sc, sc->result, ctask->itt);
+       ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
+                         sc, sc->result, task->itt);
        conn->scsirsp_pdus_cnt++;
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
+}
+
+/**
+ * iscsi_data_in_rsp - SCSI Data-In Response processing
+ * @conn: iscsi connection
+ * @hdr:  iscsi pdu
+ * @task: scsi command task
+ **/
+static void
+iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+                 struct iscsi_task *task)
+{
+       struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
+       struct scsi_cmnd *sc = task->sc;
+
+       if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
+               return;
+
+       iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
+       sc->result = (DID_OK << 16) | rhdr->cmd_status;
+       conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
+       if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
+                          ISCSI_FLAG_DATA_OVERFLOW)) {
+               int res_count = be32_to_cpu(rhdr->residual_count);
+
+               if (res_count > 0 &&
+                   (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
+                    res_count <= scsi_in(sc)->length))
+                       scsi_in(sc)->resid = res_count;
+               else
+                       sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
+       }
 
-       __iscsi_put_ctask(ctask);
+       ISCSI_DBG_SESSION(conn->session, "data in with status done "
+                         "[sc %p res %d itt 0x%x]\n",
+                         sc, sc->result, task->itt);
+       conn->scsirsp_pdus_cnt++;
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 }
 
 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
@@ -471,9 +955,9 @@ static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 {
         struct iscsi_nopout hdr;
-       struct iscsi_mgmt_task *mtask;
+       struct iscsi_task *task;
 
-       if (!rhdr && conn->ping_mtask)
+       if (!rhdr && conn->ping_task)
                return;
 
        memset(&hdr, 0, sizeof(struct iscsi_nopout));
@@ -487,18 +971,34 @@ static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
        } else
                hdr.ttt = RESERVED_ITT;
 
-       mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
-       if (!mtask) {
-               printk(KERN_ERR "Could not send nopout\n");
-               return;
-       }
-
-       /* only track our nops */
-       if (!rhdr) {
-               conn->ping_mtask = mtask;
+       task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
+       if (!task)
+               iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
+       else if (!rhdr) {
+               /* only track our nops */
+               conn->ping_task = task;
                conn->last_ping = jiffies;
        }
-       scsi_queue_work(conn->session->host, &conn->xmitwork);
+}
+
+static int iscsi_nop_out_rsp(struct iscsi_task *task,
+                            struct iscsi_nopin *nop, char *data, int datalen)
+{
+       struct iscsi_conn *conn = task->conn;
+       int rc = 0;
+
+       if (conn->ping_task != task) {
+               /*
+                * If this is not in response to one of our
+                * nops then it must be from userspace.
+                */
+               if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
+                                  data, datalen))
+                       rc = ISCSI_ERR_CONN_FAILED;
+       } else
+               mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
+       return rc;
 }
 
 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
@@ -506,136 +1006,141 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 {
        struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
        struct iscsi_hdr rejected_pdu;
-       uint32_t itt;
+       int opcode, rc = 0;
 
        conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 
-       if (reject->reason == ISCSI_REASON_DATA_DIGEST_ERROR) {
-               if (ntoh24(reject->dlength) > datalen)
-                       return ISCSI_ERR_PROTO;
+       if (ntoh24(reject->dlength) > datalen ||
+           ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
+               iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
+                                 "pdu. Invalid data length (pdu dlength "
+                                 "%u, datalen %d\n", ntoh24(reject->dlength),
+                                 datalen);
+               return ISCSI_ERR_PROTO;
+       }
+       memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
+       opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
+
+       switch (reject->reason) {
+       case ISCSI_REASON_DATA_DIGEST_ERROR:
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "pdu (op 0x%x itt 0x%x) rejected "
+                                 "due to DataDigest error.\n",
+                                 rejected_pdu.itt, opcode);
+               break;
+       case ISCSI_REASON_IMM_CMD_REJECT:
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "pdu (op 0x%x itt 0x%x) rejected. Too many "
+                                 "immediate commands.\n",
+                                 rejected_pdu.itt, opcode);
+               /*
+                * We only send one TMF at a time so if the target could not
+                * handle it, then it should get fixed (RFC mandates that
+                * a target can handle one immediate TMF per conn).
+                *
+                * For nops-outs, we could have sent more than one if
+                * the target is sending us lots of nop-ins
+                */
+               if (opcode != ISCSI_OP_NOOP_OUT)
+                       return 0;
 
-               if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
-                       memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
-                       itt = get_itt(rejected_pdu.itt);
-                       printk(KERN_ERR "itt 0x%x had pdu (op 0x%x) rejected "
-                               "due to DataDigest error.\n", itt,
-                               rejected_pdu.opcode);
+                if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG))
+                       /*
+                        * nop-out in response to target's nop-out rejected.
+                        * Just resend.
+                        */
+                       iscsi_send_nopout(conn,
+                                         (struct iscsi_nopin*)&rejected_pdu);
+               else {
+                       struct iscsi_task *task;
+                       /*
+                        * Our nop as ping got dropped. We know the target
+                        * and transport are ok so just clean up
+                        */
+                       task = iscsi_itt_to_task(conn, rejected_pdu.itt);
+                       if (!task) {
+                               iscsi_conn_printk(KERN_ERR, conn,
+                                                "Invalid pdu reject. Could "
+                                                "not lookup rejected task.\n");
+                               rc = ISCSI_ERR_BAD_ITT;
+                       } else
+                               rc = iscsi_nop_out_rsp(task,
+                                       (struct iscsi_nopin*)&rejected_pdu,
+                                       NULL, 0);
                }
+               break;
+       default:
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "pdu (op 0x%x itt 0x%x) rejected. Reason "
+                                 "code 0x%x\n", rejected_pdu.itt,
+                                 rejected_pdu.opcode, reject->reason);
+               break;
        }
-       return 0;
+       return rc;
 }
 
 /**
- * __iscsi_complete_pdu - complete pdu
- * @conn: iscsi conn
- * @hdr: iscsi header
- * @data: data buffer
- * @datalen: len of data buffer
+ * iscsi_itt_to_task - look up task by itt
+ * @conn: iscsi connection
+ * @itt: itt
  *
- * Completes pdu processing by freeing any resources allocated at
- * queuecommand or send generic. session lock must be held and verify
- * itt must have been called.
+ * This should be used for mgmt tasks like login and nops, or if
+ * the LDD's itt space does not include the session age.
+ *
+ * The session lock must be held.
  */
-int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
-                        char *data, int datalen)
+struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
 {
        struct iscsi_session *session = conn->session;
-       int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
-       struct iscsi_cmd_task *ctask;
-       struct iscsi_mgmt_task *mtask;
-       uint32_t itt;
+       int i;
+
+       if (itt == RESERVED_ITT)
+               return NULL;
+
+       if (session->tt->parse_pdu_itt)
+               session->tt->parse_pdu_itt(conn, itt, &i, NULL);
+       else
+               i = get_itt(itt);
+       if (i >= session->cmds_max)
+               return NULL;
+
+       return session->cmds[i];
+}
+EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
+
+/**
+ * __iscsi_complete_pdu - complete pdu
+ * @conn: iscsi conn
+ * @hdr: iscsi header
+ * @data: data buffer
+ * @datalen: len of data buffer
+ *
+ * Completes pdu processing by freeing any resources allocated at
+ * queuecommand or send generic. session lock must be held and verify
+ * itt must have been called.
+ */
+int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+                        char *data, int datalen)
+{
+       struct iscsi_session *session = conn->session;
+       int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
+       struct iscsi_task *task;
+       uint32_t itt;
 
        conn->last_recv = jiffies;
+       rc = iscsi_verify_itt(conn, hdr->itt);
+       if (rc)
+               return rc;
+
        if (hdr->itt != RESERVED_ITT)
                itt = get_itt(hdr->itt);
        else
                itt = ~0U;
 
-       if (itt < session->cmds_max) {
-               ctask = session->cmds[itt];
-
-               debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
-                          opcode, conn->id, ctask->itt, datalen);
-
-               switch(opcode) {
-               case ISCSI_OP_SCSI_CMD_RSP:
-                       BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
-                       iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
-                                          datalen);
-                       break;
-               case ISCSI_OP_SCSI_DATA_IN:
-                       BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
-                       if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
-                               conn->scsirsp_pdus_cnt++;
-                               __iscsi_put_ctask(ctask);
-                       }
-                       break;
-               case ISCSI_OP_R2T:
-                       /* LLD handles this for now */
-                       break;
-               default:
-                       rc = ISCSI_ERR_BAD_OPCODE;
-                       break;
-               }
-       } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
-                  itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
-               mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
-
-               debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
-                          opcode, conn->id, mtask->itt, datalen);
+       ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
+                         opcode, conn->id, itt, datalen);
 
-               iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
-               switch(opcode) {
-               case ISCSI_OP_LOGOUT_RSP:
-                       if (datalen) {
-                               rc = ISCSI_ERR_PROTO;
-                               break;
-                       }
-                       conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
-                       /* fall through */
-               case ISCSI_OP_LOGIN_RSP:
-               case ISCSI_OP_TEXT_RSP:
-                       /*
-                        * login related PDU's exp_statsn is handled in
-                        * userspace
-                        */
-                       if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
-                               rc = ISCSI_ERR_CONN_FAILED;
-                       iscsi_free_mgmt_task(conn, mtask);
-                       break;
-               case ISCSI_OP_SCSI_TMFUNC_RSP:
-                       if (datalen) {
-                               rc = ISCSI_ERR_PROTO;
-                               break;
-                       }
-
-                       iscsi_tmf_rsp(conn, hdr);
-                       iscsi_free_mgmt_task(conn, mtask);
-                       break;
-               case ISCSI_OP_NOOP_IN:
-                       if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) ||
-                           datalen) {
-                               rc = ISCSI_ERR_PROTO;
-                               break;
-                       }
-                       conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
-
-                       if (conn->ping_mtask != mtask) {
-                               /*
-                                * If this is not in response to one of our
-                                * nops then it must be from userspace.
-                                */
-                               if (iscsi_recv_pdu(conn->cls_conn, hdr, data,
-                                                  datalen))
-                                       rc = ISCSI_ERR_CONN_FAILED;
-                       }
-                       iscsi_free_mgmt_task(conn, mtask);
-                       break;
-               default:
-                       rc = ISCSI_ERR_BAD_OPCODE;
-                       break;
-               }
-       } else if (itt == ~0U) {
+       if (itt == ~0U) {
                iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
 
                switch(opcode) {
@@ -662,9 +1167,90 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                        rc = ISCSI_ERR_BAD_OPCODE;
                        break;
                }
-       } else
-               rc = ISCSI_ERR_BAD_ITT;
+               goto out;
+       }
+
+       switch(opcode) {
+       case ISCSI_OP_SCSI_CMD_RSP:
+       case ISCSI_OP_SCSI_DATA_IN:
+               task = iscsi_itt_to_ctask(conn, hdr->itt);
+               if (!task)
+                       return ISCSI_ERR_BAD_ITT;
+               task->last_xfer = jiffies;
+               break;
+       case ISCSI_OP_R2T:
+               /*
+                * LLD handles R2Ts if they need to.
+                */
+               return 0;
+       case ISCSI_OP_LOGOUT_RSP:
+       case ISCSI_OP_LOGIN_RSP:
+       case ISCSI_OP_TEXT_RSP:
+       case ISCSI_OP_SCSI_TMFUNC_RSP:
+       case ISCSI_OP_NOOP_IN:
+               task = iscsi_itt_to_task(conn, hdr->itt);
+               if (!task)
+                       return ISCSI_ERR_BAD_ITT;
+               break;
+       default:
+               return ISCSI_ERR_BAD_OPCODE;
+       }
+
+       switch(opcode) {
+       case ISCSI_OP_SCSI_CMD_RSP:
+               iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
+               break;
+       case ISCSI_OP_SCSI_DATA_IN:
+               iscsi_data_in_rsp(conn, hdr, task);
+               break;
+       case ISCSI_OP_LOGOUT_RSP:
+               iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
+               if (datalen) {
+                       rc = ISCSI_ERR_PROTO;
+                       break;
+               }
+               conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+               goto recv_pdu;
+       case ISCSI_OP_LOGIN_RSP:
+       case ISCSI_OP_TEXT_RSP:
+               iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
+               /*
+                * login related PDU's exp_statsn is handled in
+                * userspace
+                */
+               goto recv_pdu;
+       case ISCSI_OP_SCSI_TMFUNC_RSP:
+               iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
+               if (datalen) {
+                       rc = ISCSI_ERR_PROTO;
+                       break;
+               }
 
+               iscsi_tmf_rsp(conn, hdr);
+               iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
+               break;
+       case ISCSI_OP_NOOP_IN:
+               iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
+               if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
+                       rc = ISCSI_ERR_PROTO;
+                       break;
+               }
+               conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+
+               rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
+                                      data, datalen);
+               break;
+       default:
+               rc = ISCSI_ERR_BAD_OPCODE;
+               break;
+       }
+
+out:
+       return rc;
+recv_pdu:
+       if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
+               rc = ISCSI_ERR_CONN_FAILED;
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
        return rc;
 }
 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
@@ -681,130 +1267,120 @@ int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 }
 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
 
-/* verify itt (itt encoding: age+cid+itt) */
-int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
-                    uint32_t *ret_itt)
+int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
 {
        struct iscsi_session *session = conn->session;
-       struct iscsi_cmd_task *ctask;
-       uint32_t itt;
-
-       if (hdr->itt != RESERVED_ITT) {
-               if (((__force u32)hdr->itt & ISCSI_AGE_MASK) !=
-                   (session->age << ISCSI_AGE_SHIFT)) {
-                       printk(KERN_ERR "iscsi: received itt %x expected "
-                               "session age (%x)\n", (__force u32)hdr->itt,
-                               session->age & ISCSI_AGE_MASK);
-                       return ISCSI_ERR_BAD_ITT;
-               }
+       int age = 0, i = 0;
 
-               if (((__force u32)hdr->itt & ISCSI_CID_MASK) !=
-                   (conn->id << ISCSI_CID_SHIFT)) {
-                       printk(KERN_ERR "iscsi: received itt %x, expected "
-                               "CID (%x)\n", (__force u32)hdr->itt, conn->id);
-                       return ISCSI_ERR_BAD_ITT;
-               }
-               itt = get_itt(hdr->itt);
-       } else
-               itt = ~0U;
-
-       if (itt < session->cmds_max) {
-               ctask = session->cmds[itt];
+       if (itt == RESERVED_ITT)
+               return 0;
 
-               if (!ctask->sc) {
-                       printk(KERN_INFO "iscsi: dropping ctask with "
-                              "itt 0x%x\n", ctask->itt);
-                       /* force drop */
-                       return ISCSI_ERR_NO_SCSI_CMD;
-               }
+       if (session->tt->parse_pdu_itt)
+               session->tt->parse_pdu_itt(conn, itt, &i, &age);
+       else {
+               i = get_itt(itt);
+               age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
+       }
 
-               if (ctask->sc->SCp.phase != session->age) {
-                       printk(KERN_ERR "iscsi: ctask's session age %d, "
-                               "expected %d\n", ctask->sc->SCp.phase,
-                               session->age);
-                       return ISCSI_ERR_SESSION_FAILED;
-               }
+       if (age != session->age) {
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "received itt %x expected session age (%x)\n",
+                                 (__force u32)itt, session->age);
+               return ISCSI_ERR_BAD_ITT;
        }
 
-       *ret_itt = itt;
+       if (i >= session->cmds_max) {
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "received invalid itt index %u (max cmds "
+                                  "%u.\n", i, session->cmds_max);
+               return ISCSI_ERR_BAD_ITT;
+       }
        return 0;
 }
 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
 
-void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
+/**
+ * iscsi_itt_to_ctask - look up ctask by itt
+ * @conn: iscsi connection
+ * @itt: itt
+ *
+ * This should be used for cmd tasks.
+ *
+ * The session lock must be held.
+ */
+struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
 {
-       struct iscsi_session *session = conn->session;
+       struct iscsi_task *task;
+
+       if (iscsi_verify_itt(conn, itt))
+               return NULL;
+
+       task = iscsi_itt_to_task(conn, itt);
+       if (!task || !task->sc)
+               return NULL;
+
+       if (task->sc->SCp.phase != conn->session->age) {
+               iscsi_session_printk(KERN_ERR, conn->session,
+                                 "task's session age %d, expected %d\n",
+                                 task->sc->SCp.phase, conn->session->age);
+               return NULL;
+       }
+
+       return task;
+}
+EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
+
+void iscsi_session_failure(struct iscsi_session *session,
+                          enum iscsi_err err)
+{
+       struct iscsi_conn *conn;
+       struct device *dev;
        unsigned long flags;
 
        spin_lock_irqsave(&session->lock, flags);
-       if (session->state == ISCSI_STATE_FAILED) {
+       conn = session->leadconn;
+       if (session->state == ISCSI_STATE_TERMINATE || !conn) {
                spin_unlock_irqrestore(&session->lock, flags);
                return;
        }
 
-       if (conn->stop_stage == 0)
-               session->state = ISCSI_STATE_FAILED;
+       dev = get_device(&conn->cls_conn->dev);
        spin_unlock_irqrestore(&session->lock, flags);
-       set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
-       set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
-       iscsi_conn_error(conn->cls_conn, err);
-}
-EXPORT_SYMBOL_GPL(iscsi_conn_failure);
-
-static void iscsi_prep_mtask(struct iscsi_conn *conn,
-                            struct iscsi_mgmt_task *mtask)
-{
-       struct iscsi_session *session = conn->session;
-       struct iscsi_hdr *hdr = mtask->hdr;
-       struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
-
-       if (hdr->opcode != (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) &&
-           hdr->opcode != (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
-               nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
+       if (!dev)
+               return;
        /*
-        * pre-format CmdSN for outgoing PDU.
+        * if the host is being removed bypass the connection
+        * recovery initialization because we are going to kill
+        * the session.
         */
-       nop->cmdsn = cpu_to_be32(session->cmdsn);
-       if (hdr->itt != RESERVED_ITT) {
-               hdr->itt = build_itt(mtask->itt, conn->id, session->age);
-               /*
-                * TODO: We always use immediate, so we never hit this.
-                * If we start to send tmfs or nops as non-immediate then
-                * we should start checking the cmdsn numbers for mgmt tasks.
-                */
-               if (conn->c_stage == ISCSI_CONN_STARTED &&
-                   !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
-                       session->queued_cmdsn++;
-                       session->cmdsn++;
-               }
-       }
-
-       if (session->tt->init_mgmt_task)
-               session->tt->init_mgmt_task(conn, mtask);
-
-       debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
-                  hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
-                  mtask->data_count);
+       if (err == ISCSI_ERR_INVALID_HOST)
+               iscsi_conn_error_event(conn->cls_conn, err);
+       else
+               iscsi_conn_failure(conn, err);
+       put_device(dev);
 }
+EXPORT_SYMBOL_GPL(iscsi_session_failure);
 
-static int iscsi_xmit_mtask(struct iscsi_conn *conn)
+void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 {
-       struct iscsi_hdr *hdr = conn->mtask->hdr;
-       int rc;
+       struct iscsi_session *session = conn->session;
+       unsigned long flags;
 
-       if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
-               conn->session->state = ISCSI_STATE_LOGGING_OUT;
-       spin_unlock_bh(&conn->session->lock);
+       spin_lock_irqsave(&session->lock, flags);
+       if (session->state == ISCSI_STATE_FAILED) {
+               spin_unlock_irqrestore(&session->lock, flags);
+               return;
+       }
 
-       rc = conn->session->tt->xmit_mgmt_task(conn, conn->mtask);
-       spin_lock_bh(&conn->session->lock);
-       if (rc)
-               return rc;
+       if (conn->stop_stage == 0)
+               session->state = ISCSI_STATE_FAILED;
+       spin_unlock_irqrestore(&session->lock, flags);
 
-       /* done with this in-progress mtask */
-       conn->mtask = NULL;
-       return 0;
+       set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+       set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
+       iscsi_conn_error_event(conn->cls_conn, err);
 }
+EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 
 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 {
@@ -814,46 +1390,57 @@ static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
         * Check for iSCSI window and take care of CmdSN wrap-around
         */
        if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
-               debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
-                          "CmdSN %u/%u\n", session->exp_cmdsn,
-                          session->max_cmdsn, session->cmdsn,
-                          session->queued_cmdsn);
+               ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
+                                 "%u MaxCmdSN %u CmdSN %u/%u\n",
+                                 session->exp_cmdsn, session->max_cmdsn,
+                                 session->cmdsn, session->queued_cmdsn);
                return -ENOSPC;
        }
        return 0;
 }
 
-static int iscsi_xmit_ctask(struct iscsi_conn *conn)
+static int iscsi_xmit_task(struct iscsi_conn *conn)
 {
-       struct iscsi_cmd_task *ctask = conn->ctask;
+       struct iscsi_task *task = conn->task;
        int rc;
 
-       __iscsi_get_ctask(ctask);
+       if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
+               return -ENODATA;
+
+       __iscsi_get_task(task);
        spin_unlock_bh(&conn->session->lock);
-       rc = conn->session->tt->xmit_cmd_task(conn, ctask);
+       rc = conn->session->tt->xmit_task(task);
        spin_lock_bh(&conn->session->lock);
-       __iscsi_put_ctask(ctask);
-       if (!rc)
-               /* done with this ctask */
-               conn->ctask = NULL;
+       if (!rc) {
+               /* done with this task */
+               task->last_xfer = jiffies;
+               conn->task = NULL;
+       }
+       __iscsi_put_task(task);
        return rc;
 }
 
 /**
- * iscsi_requeue_ctask - requeue ctask to run from session workqueue
- * @ctask: ctask to requeue
+ * iscsi_requeue_task - requeue task to run from session workqueue
+ * @task: task to requeue
  *
- * LLDs that need to run a ctask from the session workqueue should call
- * this. The session lock must be held.
+ * LLDs that need to run a task from the session workqueue should call
+ * this. The session lock must be held. This should only be called
+ * by software drivers.
  */
-void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask)
+void iscsi_requeue_task(struct iscsi_task *task)
 {
-       struct iscsi_conn *conn = ctask->conn;
+       struct iscsi_conn *conn = task->conn;
 
-       list_move_tail(&ctask->running, &conn->requeue);
-       scsi_queue_work(conn->session->host, &conn->xmitwork);
+       /*
+        * this may be on the requeue list already if the xmit_task callout
+        * is handling the r2ts while we are adding new ones
+        */
+       if (list_empty(&task->running))
+               list_add_tail(&task->running, &conn->requeue);
+       iscsi_conn_queue_work(conn);
 }
-EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
+EXPORT_SYMBOL_GPL(iscsi_requeue_task);
 
 /**
  * iscsi_data_xmit - xmit any command into the scheduled connection
@@ -866,25 +1453,20 @@ EXPORT_SYMBOL_GPL(iscsi_requeue_ctask);
  **/
 static int iscsi_data_xmit(struct iscsi_conn *conn)
 {
+       struct iscsi_task *task;
        int rc = 0;
 
        spin_lock_bh(&conn->session->lock);
-       if (unlikely(conn->suspend_tx)) {
-               debug_scsi("conn %d Tx suspended!\n", conn->id);
+       if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
+               ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
                spin_unlock_bh(&conn->session->lock);
                return -ENODATA;
        }
 
-       if (conn->ctask) {
-               rc = iscsi_xmit_ctask(conn);
-               if (rc)
-                       goto again;
-       }
-
-       if (conn->mtask) {
-               rc = iscsi_xmit_mtask(conn);
+       if (conn->task) {
+               rc = iscsi_xmit_task(conn);
                if (rc)
-                       goto again;
+                       goto done;
        }
 
        /*
@@ -894,44 +1476,44 @@ static int iscsi_data_xmit(struct iscsi_conn *conn)
         */
 check_mgmt:
        while (!list_empty(&conn->mgmtqueue)) {
-               conn->mtask = list_entry(conn->mgmtqueue.next,
-                                        struct iscsi_mgmt_task, running);
-               if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
-                       iscsi_free_mgmt_task(conn, conn->mtask);
-                       conn->mtask = NULL;
+               conn->task = list_entry(conn->mgmtqueue.next,
+                                        struct iscsi_task, running);
+               list_del_init(&conn->task->running);
+               if (iscsi_prep_mgmt_task(conn, conn->task)) {
+                       __iscsi_put_task(conn->task);
+                       conn->task = NULL;
                        continue;
                }
-
-               iscsi_prep_mtask(conn, conn->mtask);
-               list_move_tail(conn->mgmtqueue.next, &conn->mgmt_run_list);
-               rc = iscsi_xmit_mtask(conn);
+               rc = iscsi_xmit_task(conn);
                if (rc)
-                       goto again;
+                       goto done;
        }
 
        /* process pending command queue */
-       while (!list_empty(&conn->xmitqueue)) {
-               if (conn->tmf_state == TMF_QUEUED)
-                       break;
-
-               conn->ctask = list_entry(conn->xmitqueue.next,
-                                        struct iscsi_cmd_task, running);
+       while (!list_empty(&conn->cmdqueue)) {
+               conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
+                                       running);
+               list_del_init(&conn->task->running);
                if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
-                       fail_command(conn, conn->ctask, DID_IMM_RETRY << 16);
+                       fail_scsi_task(conn->task, DID_IMM_RETRY);
                        continue;
                }
-               if (iscsi_prep_scsi_cmd_pdu(conn->ctask)) {
-                       fail_command(conn, conn->ctask, DID_ABORT << 16);
+               rc = iscsi_prep_scsi_cmd_pdu(conn->task);
+               if (rc) {
+                       if (rc == -ENOMEM || rc == -EACCES) {
+                               list_add_tail(&conn->task->running,
+                                             &conn->cmdqueue);
+                               conn->task = NULL;
+                               goto done;
+                       } else
+                               fail_scsi_task(conn->task, DID_ABORT);
                        continue;
                }
-               conn->session->tt->init_cmd_task(conn->ctask);
-               conn->ctask->state = ISCSI_TASK_RUNNING;
-               list_move_tail(conn->xmitqueue.next, &conn->run_list);
-               rc = iscsi_xmit_ctask(conn);
+               rc = iscsi_xmit_task(conn);
                if (rc)
-                       goto again;
+                       goto done;
                /*
-                * we could continuously get new ctask requests so
+                * we could continuously get new task requests so
                 * we need to check the mgmt queue for nops that need to
                 * be sent to aviod starvation
                 */
@@ -940,31 +1522,30 @@ check_mgmt:
        }
 
        while (!list_empty(&conn->requeue)) {
-               if (conn->session->fast_abort && conn->tmf_state != TMF_INITIAL)
-                       break;
-
                /*
                 * we always do fastlogout - conn stop code will clean up.
                 */
                if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
                        break;
 
-               conn->ctask = list_entry(conn->requeue.next,
-                                        struct iscsi_cmd_task, running);
-               conn->ctask->state = ISCSI_TASK_RUNNING;
-               list_move_tail(conn->requeue.next, &conn->run_list);
-               rc = iscsi_xmit_ctask(conn);
+               task = list_entry(conn->requeue.next, struct iscsi_task,
+                                 running);
+               if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
+                       break;
+
+               conn->task = task;
+               list_del_init(&conn->task->running);
+               conn->task->state = ISCSI_TASK_RUNNING;
+               rc = iscsi_xmit_task(conn);
                if (rc)
-                       goto again;
+                       goto done;
                if (!list_empty(&conn->mgmtqueue))
                        goto check_mgmt;
        }
        spin_unlock_bh(&conn->session->lock);
        return -ENODATA;
 
-again:
-       if (unlikely(conn->suspend_tx))
-               rc = -ENODATA;
+done:
        spin_unlock_bh(&conn->session->lock);
        return rc;
 }
@@ -982,6 +1563,29 @@ static void iscsi_xmitworker(struct work_struct *work)
        } while (rc >= 0 || rc == -EAGAIN);
 }
 
+static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
+                                                 struct scsi_cmnd *sc)
+{
+       struct iscsi_task *task;
+
+       if (!kfifo_out(&conn->session->cmdpool.queue,
+                        (void *) &task, sizeof(void *)))
+               return NULL;
+
+       sc->SCp.phase = conn->session->age;
+       sc->SCp.ptr = (char *) task;
+
+       atomic_set(&task->refcount, 1);
+       task->state = ISCSI_TASK_PENDING;
+       task->conn = conn;
+       task->sc = sc;
+       task->have_checked_conn = false;
+       task->last_timeout = jiffies;
+       task->last_xfer = jiffies;
+       INIT_LIST_HEAD(&task->running);
+       return task;
+}
+
 enum {
        FAILURE_BAD_HOST = 1,
        FAILURE_SESSION_FAILED,
@@ -992,32 +1596,38 @@ enum {
        FAILURE_SESSION_IN_RECOVERY,
        FAILURE_SESSION_RECOVERY_TIMEOUT,
        FAILURE_SESSION_LOGGING_OUT,
+       FAILURE_SESSION_NOT_READY,
 };
 
 int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 {
+       struct iscsi_cls_session *cls_session;
        struct Scsi_Host *host;
+       struct iscsi_host *ihost;
        int reason = 0;
        struct iscsi_session *session;
        struct iscsi_conn *conn;
-       struct iscsi_cmd_task *ctask = NULL;
+       struct iscsi_task *task = NULL;
 
        sc->scsi_done = done;
        sc->result = 0;
        sc->SCp.ptr = NULL;
 
        host = sc->device->host;
-       session = iscsi_hostdata(host->hostdata);
+       ihost = shost_priv(host);
+       spin_unlock(host->host_lock);
 
+       cls_session = starget_to_session(scsi_target(sc->device));
+       session = cls_session->dd_data;
        spin_lock(&session->lock);
 
-       /*
-        * ISCSI_STATE_FAILED is a temp. state. The recovery
-        * code will decide what is best to do with command queued
-        * during this time
-        */
-       if (session->state != ISCSI_STATE_LOGGED_IN &&
-           session->state != ISCSI_STATE_FAILED) {
+       reason = iscsi_session_chkready(cls_session);
+       if (reason) {
+               sc->result = reason;
+               goto fault;
+       }
+
+       if (session->state != ISCSI_STATE_LOGGED_IN) {
                /*
                 * to handle the race between when we set the recovery state
                 * and block the session we requeue here (commands could
@@ -1025,20 +1635,26 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
                 * up because the block code is not locked)
                 */
                switch (session->state) {
+               case ISCSI_STATE_FAILED:
                case ISCSI_STATE_IN_RECOVERY:
                        reason = FAILURE_SESSION_IN_RECOVERY;
-                       goto reject;
+                       sc->result = DID_IMM_RETRY << 16;
+                       break;
                case ISCSI_STATE_LOGGING_OUT:
                        reason = FAILURE_SESSION_LOGGING_OUT;
-                       goto reject;
+                       sc->result = DID_IMM_RETRY << 16;
+                       break;
                case ISCSI_STATE_RECOVERY_FAILED:
                        reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
+                       sc->result = DID_TRANSPORT_FAILFAST << 16;
                        break;
                case ISCSI_STATE_TERMINATE:
                        reason = FAILURE_SESSION_TERMINATE;
+                       sc->result = DID_NO_CONNECT << 16;
                        break;
                default:
                        reason = FAILURE_SESSION_FREED;
+                       sc->result = DID_NO_CONNECT << 16;
                }
                goto fault;
        }
@@ -1046,6 +1662,13 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
        conn = session->leadconn;
        if (!conn) {
                reason = FAILURE_SESSION_FREED;
+               sc->result = DID_NO_CONNECT << 16;
+               goto fault;
+       }
+
+       if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
+               reason = FAILURE_SESSION_IN_RECOVERY;
+               sc->result = DID_REQUEUE;
                goto fault;
        }
 
@@ -1054,111 +1677,95 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
                goto reject;
        }
 
-       if (!__kfifo_get(session->cmdpool.queue, (void*)&ctask,
-                        sizeof(void*))) {
+       task = iscsi_alloc_task(conn, sc);
+       if (!task) {
                reason = FAILURE_OOM;
                goto reject;
        }
-       session->queued_cmdsn++;
 
-       sc->SCp.phase = session->age;
-       sc->SCp.ptr = (char *)ctask;
-
-       atomic_set(&ctask->refcount, 1);
-       ctask->state = ISCSI_TASK_PENDING;
-       ctask->conn = conn;
-       ctask->sc = sc;
-       INIT_LIST_HEAD(&ctask->running);
+       if (!ihost->workq) {
+               reason = iscsi_prep_scsi_cmd_pdu(task);
+               if (reason) {
+                       if (reason == -ENOMEM ||  reason == -EACCES) {
+                               reason = FAILURE_OOM;
+                               goto prepd_reject;
+                       } else {
+                               sc->result = DID_ABORT << 16;
+                               goto prepd_fault;
+                       }
+               }
+               if (session->tt->xmit_task(task)) {
+                       session->cmdsn--;
+                       reason = FAILURE_SESSION_NOT_READY;
+                       goto prepd_reject;
+               }
+       } else {
+               list_add_tail(&task->running, &conn->cmdqueue);
+               iscsi_conn_queue_work(conn);
+       }
 
-       list_add_tail(&ctask->running, &conn->xmitqueue);
+       session->queued_cmdsn++;
        spin_unlock(&session->lock);
-
-       scsi_queue_work(host, &conn->xmitwork);
+       spin_lock(host->host_lock);
        return 0;
 
+prepd_reject:
+       sc->scsi_done = NULL;
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 reject:
        spin_unlock(&session->lock);
-       debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
-       return SCSI_MLQUEUE_HOST_BUSY;
-
+       ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
+                         sc->cmnd[0], reason);
+       spin_lock(host->host_lock);
+       return SCSI_MLQUEUE_TARGET_BUSY;
+
+prepd_fault:
+       sc->scsi_done = NULL;
+       iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 fault:
        spin_unlock(&session->lock);
-       printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
-              sc->cmnd[0], reason);
-       sc->result = (DID_NO_CONNECT << 16);
-       scsi_set_resid(sc, scsi_bufflen(sc));
-       sc->scsi_done(sc);
+       ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
+                         sc->cmnd[0], reason);
+       if (!scsi_bidi_cmnd(sc))
+               scsi_set_resid(sc, scsi_bufflen(sc));
+       else {
+               scsi_out(sc)->resid = scsi_out(sc)->length;
+               scsi_in(sc)->resid = scsi_in(sc)->length;
+       }
+       done(sc);
+       spin_lock(host->host_lock);
        return 0;
 }
 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 
-int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
+int iscsi_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
 {
-       if (depth > ISCSI_MAX_CMD_PER_LUN)
-               depth = ISCSI_MAX_CMD_PER_LUN;
-       scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
+       switch (reason) {
+       case SCSI_QDEPTH_DEFAULT:
+               scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
+               break;
+       case SCSI_QDEPTH_QFULL:
+               scsi_track_queue_full(sdev, depth);
+               break;
+       case SCSI_QDEPTH_RAMP_UP:
+               scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
+               break;
+       default:
+               return -EOPNOTSUPP;
+       }
        return sdev->queue_depth;
 }
 EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
 
-void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
+int iscsi_target_alloc(struct scsi_target *starget)
 {
-       struct iscsi_session *session = class_to_transport_session(cls_session);
-
-       spin_lock_bh(&session->lock);
-       if (session->state != ISCSI_STATE_LOGGED_IN) {
-               session->state = ISCSI_STATE_RECOVERY_FAILED;
-               if (session->leadconn)
-                       wake_up(&session->leadconn->ehwait);
-       }
-       spin_unlock_bh(&session->lock);
-}
-EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
+       struct iscsi_cls_session *cls_session = starget_to_session(starget);
+       struct iscsi_session *session = cls_session->dd_data;
 
-int iscsi_eh_host_reset(struct scsi_cmnd *sc)
-{
-       struct Scsi_Host *host = sc->device->host;
-       struct iscsi_session *session = iscsi_hostdata(host->hostdata);
-       struct iscsi_conn *conn = session->leadconn;
-
-       mutex_lock(&session->eh_mutex);
-       spin_lock_bh(&session->lock);
-       if (session->state == ISCSI_STATE_TERMINATE) {
-failed:
-               debug_scsi("failing host reset: session terminated "
-                          "[CID %d age %d]\n", conn->id, session->age);
-               spin_unlock_bh(&session->lock);
-               mutex_unlock(&session->eh_mutex);
-               return FAILED;
-       }
-
-       spin_unlock_bh(&session->lock);
-       mutex_unlock(&session->eh_mutex);
-       /*
-        * we drop the lock here but the leadconn cannot be destoyed while
-        * we are in the scsi eh
-        */
-       iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
-
-       debug_scsi("iscsi_eh_host_reset wait for relogin\n");
-       wait_event_interruptible(conn->ehwait,
-                                session->state == ISCSI_STATE_TERMINATE ||
-                                session->state == ISCSI_STATE_LOGGED_IN ||
-                                session->state == ISCSI_STATE_RECOVERY_FAILED);
-       if (signal_pending(current))
-               flush_signals(current);
-
-       mutex_lock(&session->eh_mutex);
-       spin_lock_bh(&session->lock);
-       if (session->state == ISCSI_STATE_LOGGED_IN)
-               printk(KERN_INFO "iscsi: host reset succeeded\n");
-       else
-               goto failed;
-       spin_unlock_bh(&session->lock);
-       mutex_unlock(&session->eh_mutex);
-       return SUCCESS;
+       starget->can_queue = session->scsi_cmds_max;
+       return 0;
 }
-EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
+EXPORT_SYMBOL_GPL(iscsi_target_alloc);
 
 static void iscsi_tmf_timedout(unsigned long data)
 {
@@ -1168,7 +1775,7 @@ static void iscsi_tmf_timedout(unsigned long data)
        spin_lock(&session->lock);
        if (conn->tmf_state == TMF_QUEUED) {
                conn->tmf_state = TMF_TIMEDOUT;
-               debug_scsi("tmf timedout\n");
+               ISCSI_DBG_EH(session, "tmf timedout\n");
                /* unblock eh_abort() */
                wake_up(&conn->ehwait);
        }
@@ -1180,15 +1787,15 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
                                   int timeout)
 {
        struct iscsi_session *session = conn->session;
-       struct iscsi_mgmt_task *mtask;
+       struct iscsi_task *task;
 
-       mtask = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
+       task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
                                      NULL, 0);
-       if (!mtask) {
+       if (!task) {
                spin_unlock_bh(&session->lock);
                iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
                spin_lock_bh(&session->lock);
-               debug_scsi("tmf exec failure\n");
+               ISCSI_DBG_EH(session, "tmf exec failure\n");
                return -EPERM;
        }
        conn->tmfcmd_pdus_cnt++;
@@ -1196,11 +1803,10 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
        conn->tmf_timer.function = iscsi_tmf_timedout;
        conn->tmf_timer.data = (unsigned long)conn;
        add_timer(&conn->tmf_timer);
-       debug_scsi("tmf set timeout\n");
+       ISCSI_DBG_EH(session, "tmf set timeout\n");
 
        spin_unlock_bh(&session->lock);
        mutex_unlock(&session->eh_mutex);
-       scsi_queue_work(session->host, &conn->xmitwork);
 
        /*
         * block eh thread until:
@@ -1219,7 +1825,7 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
 
        mutex_lock(&session->eh_mutex);
        spin_lock_bh(&session->lock);
-       /* if the session drops it will clean up the mtask */
+       /* if the session drops it will clean up the task */
        if (age != session->age ||
            session->state != ISCSI_STATE_LOGGED_IN)
                return -ENOTCONN;
@@ -1230,63 +1836,100 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
  * Fail commands. session lock held and recv side suspended and xmit
  * thread flushed
  */
-static void fail_all_commands(struct iscsi_conn *conn, unsigned lun)
+static void fail_scsi_tasks(struct iscsi_conn *conn, unsigned lun,
+                           int error)
 {
-       struct iscsi_cmd_task *ctask, *tmp;
+       struct iscsi_task *task;
+       int i;
 
-       if (conn->ctask && (conn->ctask->sc->device->lun == lun || lun == -1))
-               conn->ctask = NULL;
+       for (i = 0; i < conn->session->cmds_max; i++) {
+               task = conn->session->cmds[i];
+               if (!task->sc || task->state == ISCSI_TASK_FREE)
+                       continue;
 
-       /* flush pending */
-       list_for_each_entry_safe(ctask, tmp, &conn->xmitqueue, running) {
-               if (lun == ctask->sc->device->lun || lun == -1) {
-                       debug_scsi("failing pending sc %p itt 0x%x\n",
-                                  ctask->sc, ctask->itt);
-                       fail_command(conn, ctask, DID_BUS_BUSY << 16);
-               }
-       }
+               if (lun != -1 && lun != task->sc->device->lun)
+                       continue;
 
-       list_for_each_entry_safe(ctask, tmp, &conn->requeue, running) {
-               if (lun == ctask->sc->device->lun || lun == -1) {
-                       debug_scsi("failing requeued sc %p itt 0x%x\n",
-                                  ctask->sc, ctask->itt);
-                       fail_command(conn, ctask, DID_BUS_BUSY << 16);
-               }
+               ISCSI_DBG_SESSION(conn->session,
+                                 "failing sc %p itt 0x%x state %d\n",
+                                 task->sc, task->itt, task->state);
+               fail_scsi_task(task, error);
        }
+}
 
-       /* fail all other running */
-       list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
-               if (lun == ctask->sc->device->lun || lun == -1) {
-                       debug_scsi("failing in progress sc %p itt 0x%x\n",
-                                  ctask->sc, ctask->itt);
-                       fail_command(conn, ctask, DID_BUS_BUSY << 16);
-               }
-       }
+/**
+ * iscsi_suspend_queue - suspend iscsi_queuecommand
+ * @conn: iscsi conn to stop queueing IO on
+ *
+ * This grabs the session lock to make sure no one is in
+ * xmit_task/queuecommand, and then sets suspend to prevent
+ * new commands from being queued. This only needs to be called
+ * by offload drivers that need to sync a path like ep disconnect
+ * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
+ * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
+ */
+void iscsi_suspend_queue(struct iscsi_conn *conn)
+{
+       spin_lock_bh(&conn->session->lock);
+       set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+       spin_unlock_bh(&conn->session->lock);
 }
+EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
 
-static void iscsi_suspend_tx(struct iscsi_conn *conn)
+/**
+ * iscsi_suspend_tx - suspend iscsi_data_xmit
+ * @conn: iscsi conn tp stop processing IO on.
+ *
+ * This function sets the suspend bit to prevent iscsi_data_xmit
+ * from sending new IO, and if work is queued on the xmit thread
+ * it will wait for it to be completed.
+ */
+void iscsi_suspend_tx(struct iscsi_conn *conn)
 {
+       struct Scsi_Host *shost = conn->session->host;
+       struct iscsi_host *ihost = shost_priv(shost);
+
        set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
-       scsi_flush_work(conn->session->host);
+       if (ihost->workq)
+               flush_workqueue(ihost->workq);
 }
+EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
 
 static void iscsi_start_tx(struct iscsi_conn *conn)
 {
        clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
-       scsi_queue_work(conn->session->host, &conn->xmitwork);
+       iscsi_conn_queue_work(conn);
+}
+
+/*
+ * We want to make sure a ping is in flight. It has timed out.
+ * And we are not busy processing a pdu that is making
+ * progress but got started before the ping and is taking a while
+ * to complete so the ping is just stuck behind it in a queue.
+ */
+static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
+{
+       if (conn->ping_task &&
+           time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
+                          (conn->ping_timeout * HZ), jiffies))
+               return 1;
+       else
+               return 0;
 }
 
-static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
+static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
 {
+       enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
+       struct iscsi_task *task = NULL, *running_task;
        struct iscsi_cls_session *cls_session;
        struct iscsi_session *session;
        struct iscsi_conn *conn;
-       enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
+       int i;
 
-       cls_session = starget_to_session(scsi_target(scmd->device));
-       session = class_to_transport_session(cls_session);
+       cls_session = starget_to_session(scsi_target(sc->device));
+       session = cls_session->dd_data;
 
-       debug_scsi("scsi cmd %p timedout\n", scmd);
+       ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
 
        spin_lock(&session->lock);
        if (session->state != ISCSI_STATE_LOGGED_IN) {
@@ -1294,14 +1937,41 @@ static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
                 * We are probably in the middle of iscsi recovery so let
                 * that complete and handle the error.
                 */
-               rc = EH_RESET_TIMER;
+               rc = BLK_EH_RESET_TIMER;
                goto done;
        }
 
        conn = session->leadconn;
        if (!conn) {
                /* In the middle of shuting down */
-               rc = EH_RESET_TIMER;
+               rc = BLK_EH_RESET_TIMER;
+               goto done;
+       }
+
+       task = (struct iscsi_task *)sc->SCp.ptr;
+       if (!task) {
+               /*
+                * Raced with completion. Just reset timer, and let it
+                * complete normally
+                */
+               rc = BLK_EH_RESET_TIMER;
+               goto done;
+       }
+
+       /*
+        * If we have sent (at least queued to the network layer) a pdu or
+        * recvd one for the task since the last timeout ask for
+        * more time. If on the next timeout we have not made progress
+        * we can check if it is the task or connection when we send the
+        * nop as a ping.
+        */
+       if (time_after(task->last_xfer, task->last_timeout)) {
+               ISCSI_DBG_EH(session, "Command making progress. Asking "
+                            "scsi-ml for more time to complete. "
+                            "Last data xfer at %lu. Last timeout was at "
+                            "%lu\n.", task->last_xfer, task->last_timeout);
+               task->have_checked_conn = false;
+               rc = BLK_EH_RESET_TIMER;
                goto done;
        }
 
@@ -1311,22 +1981,73 @@ static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
         * if the ping timedout then we are in the middle of cleaning up
         * and can let the iscsi eh handle it
         */
-       if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
-                           (conn->ping_timeout * HZ), jiffies))
-               rc = EH_RESET_TIMER;
+       if (iscsi_has_ping_timed_out(conn)) {
+               rc = BLK_EH_RESET_TIMER;
+               goto done;
+       }
+
+       for (i = 0; i < conn->session->cmds_max; i++) {
+               running_task = conn->session->cmds[i];
+               if (!running_task->sc || running_task == task ||
+                    running_task->state != ISCSI_TASK_RUNNING)
+                       continue;
+
+               /*
+                * Only check if cmds started before this one have made
+                * progress, or this could never fail
+                */
+               if (time_after(running_task->sc->jiffies_at_alloc,
+                              task->sc->jiffies_at_alloc))
+                       continue;
+
+               if (time_after(running_task->last_xfer, task->last_timeout)) {
+                       /*
+                        * This task has not made progress, but a task
+                        * started before us has transferred data since
+                        * we started/last-checked. We could be queueing
+                        * too many tasks or the LU is bad.
+                        *
+                        * If the device is bad the cmds ahead of us on
+                        * other devs will complete, and this loop will
+                        * eventually fail starting the scsi eh.
+                        */
+                       ISCSI_DBG_EH(session, "Command has not made progress "
+                                    "but commands ahead of it have. "
+                                    "Asking scsi-ml for more time to "
+                                    "complete. Our last xfer vs running task "
+                                    "last xfer %lu/%lu. Last check %lu.\n",
+                                    task->last_xfer, running_task->last_xfer,
+                                    task->last_timeout);
+                       rc = BLK_EH_RESET_TIMER;
+                       goto done;
+               }
+       }
+
+       /* Assumes nop timeout is shorter than scsi cmd timeout */
+       if (task->have_checked_conn)
+               goto done;
+
        /*
-        * if we are about to check the transport then give the command
-        * more time
+        * Checking the transport already or nop from a cmd timeout still
+        * running
         */
-       if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
-                          jiffies))
-               rc = EH_RESET_TIMER;
-       /* if in the middle of checking the transport then give us more time */
-       if (conn->ping_mtask)
-               rc = EH_RESET_TIMER;
+       if (conn->ping_task) {
+               task->have_checked_conn = true;
+               rc = BLK_EH_RESET_TIMER;
+               goto done;
+       }
+
+       /* Make sure there is a transport check done */
+       iscsi_send_nopout(conn, NULL);
+       task->have_checked_conn = true;
+       rc = BLK_EH_RESET_TIMER;
+
 done:
+       if (task)
+               task->last_timeout = jiffies;
        spin_unlock(&session->lock);
-       debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
+       ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
+                    "timer reset" : "nh");
        return rc;
 }
 
@@ -1334,69 +2055,70 @@ static void iscsi_check_transport_timeouts(unsigned long data)
 {
        struct iscsi_conn *conn = (struct iscsi_conn *)data;
        struct iscsi_session *session = conn->session;
-       unsigned long timeout, next_timeout = 0, last_recv;
+       unsigned long recv_timeout, next_timeout = 0, last_recv;
 
        spin_lock(&session->lock);
        if (session->state != ISCSI_STATE_LOGGED_IN)
                goto done;
 
-       timeout = conn->recv_timeout;
-       if (!timeout)
+       recv_timeout = conn->recv_timeout;
+       if (!recv_timeout)
                goto done;
 
-       timeout *= HZ;
+       recv_timeout *= HZ;
        last_recv = conn->last_recv;
-       if (time_before_eq(last_recv + timeout + (conn->ping_timeout * HZ),
-                          jiffies)) {
-               printk(KERN_ERR "ping timeout of %d secs expired, "
-                      "last rx %lu, last ping %lu, now %lu\n",
-                      conn->ping_timeout, last_recv,
-                      conn->last_ping, jiffies);
+
+       if (iscsi_has_ping_timed_out(conn)) {
+               iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
+                                 "expired, recv timeout %d, last rx %lu, "
+                                 "last ping %lu, now %lu\n",
+                                 conn->ping_timeout, conn->recv_timeout,
+                                 last_recv, conn->last_ping, jiffies);
                spin_unlock(&session->lock);
                iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
                return;
        }
 
-       if (time_before_eq(last_recv + timeout, jiffies)) {
-               if (time_before_eq(conn->last_ping, last_recv)) {
-                       /* send a ping to try to provoke some traffic */
-                       debug_scsi("Sending nopout as ping on conn %p\n", conn);
-                       iscsi_send_nopout(conn, NULL);
-               }
-               next_timeout = last_recv + timeout + (conn->ping_timeout * HZ);
-       } else {
-               next_timeout = last_recv + timeout;
-       }
+       if (time_before_eq(last_recv + recv_timeout, jiffies)) {
+               /* send a ping to try to provoke some traffic */
+               ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
+               iscsi_send_nopout(conn, NULL);
+               next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
+       } else
+               next_timeout = last_recv + recv_timeout;
 
-       if (next_timeout) {
-               debug_scsi("Setting next tmo %lu\n", next_timeout);
-               mod_timer(&conn->transport_timer, next_timeout);
-       }
+       ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
+       mod_timer(&conn->transport_timer, next_timeout);
 done:
        spin_unlock(&session->lock);
 }
 
-static void iscsi_prep_abort_task_pdu(struct iscsi_cmd_task *ctask,
+static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
                                      struct iscsi_tm *hdr)
 {
        memset(hdr, 0, sizeof(*hdr));
        hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
        hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
        hdr->flags |= ISCSI_FLAG_CMD_FINAL;
-       memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
-       hdr->rtt = ctask->hdr->itt;
-       hdr->refcmdsn = ctask->hdr->cmdsn;
+       memcpy(hdr->lun, task->lun, sizeof(hdr->lun));
+       hdr->rtt = task->hdr_itt;
+       hdr->refcmdsn = task->cmdsn;
 }
 
 int iscsi_eh_abort(struct scsi_cmnd *sc)
 {
-       struct Scsi_Host *host = sc->device->host;
-       struct iscsi_session *session = iscsi_hostdata(host->hostdata);
+       struct iscsi_cls_session *cls_session;
+       struct iscsi_session *session;
        struct iscsi_conn *conn;
-       struct iscsi_cmd_task *ctask;
+       struct iscsi_task *task;
        struct iscsi_tm *hdr;
        int rc, age;
 
+       cls_session = starget_to_session(scsi_target(sc->device));
+       session = cls_session->dd_data;
+
+       ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
+
        mutex_lock(&session->eh_mutex);
        spin_lock_bh(&session->lock);
        /*
@@ -1404,7 +2126,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
         * got the command.
         */
        if (!sc->SCp.ptr) {
-               debug_scsi("sc never reached iscsi layer or it completed.\n");
+               ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
+                                     "it completed.\n");
                spin_unlock_bh(&session->lock);
                mutex_unlock(&session->eh_mutex);
                return SUCCESS;
@@ -1418,6 +2141,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
            sc->SCp.phase != session->age) {
                spin_unlock_bh(&session->lock);
                mutex_unlock(&session->eh_mutex);
+               ISCSI_DBG_EH(session, "failing abort due to dropped "
+                                 "session.\n");
                return FAILED;
        }
 
@@ -1425,17 +2150,18 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
        conn->eh_abort_cnt++;
        age = session->age;
 
-       ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
-       debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
+       task = (struct iscsi_task *)sc->SCp.ptr;
+       ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
+                    sc, task->itt);
 
-       /* ctask completed before time out */
-       if (!ctask->sc) {
-               debug_scsi("sc completed while abort in progress\n");
+       /* task completed before time out */
+       if (!task->sc) {
+               ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
                goto success;
        }
 
-       if (ctask->state == ISCSI_TASK_PENDING) {
-               fail_command(conn, ctask, DID_ABORT << 16);
+       if (task->state == ISCSI_TASK_PENDING) {
+               fail_scsi_task(task, DID_ABORT);
                goto success;
        }
 
@@ -1444,82 +2170,256 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
                goto failed;
        conn->tmf_state = TMF_QUEUED;
 
-       hdr = &conn->tmhdr;
-       iscsi_prep_abort_task_pdu(ctask, hdr);
+       hdr = &conn->tmhdr;
+       iscsi_prep_abort_task_pdu(task, hdr);
+
+       if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
+               rc = FAILED;
+               goto failed;
+       }
+
+       switch (conn->tmf_state) {
+       case TMF_SUCCESS:
+               spin_unlock_bh(&session->lock);
+               /*
+                * stop tx side incase the target had sent a abort rsp but
+                * the initiator was still writing out data.
+                */
+               iscsi_suspend_tx(conn);
+               /*
+                * we do not stop the recv side because targets have been
+                * good and have never sent us a successful tmf response
+                * then sent more data for the cmd.
+                */
+               spin_lock_bh(&session->lock);
+               fail_scsi_task(task, DID_ABORT);
+               conn->tmf_state = TMF_INITIAL;
+               memset(hdr, 0, sizeof(*hdr));
+               spin_unlock_bh(&session->lock);
+               iscsi_start_tx(conn);
+               goto success_unlocked;
+       case TMF_TIMEDOUT:
+               spin_unlock_bh(&session->lock);
+               iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+               goto failed_unlocked;
+       case TMF_NOT_FOUND:
+               if (!sc->SCp.ptr) {
+                       conn->tmf_state = TMF_INITIAL;
+                       memset(hdr, 0, sizeof(*hdr));
+                       /* task completed before tmf abort response */
+                       ISCSI_DBG_EH(session, "sc completed while abort in "
+                                             "progress\n");
+                       goto success;
+               }
+               /* fall through */
+       default:
+               conn->tmf_state = TMF_INITIAL;
+               goto failed;
+       }
+
+success:
+       spin_unlock_bh(&session->lock);
+success_unlocked:
+       ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
+                    sc, task->itt);
+       mutex_unlock(&session->eh_mutex);
+       return SUCCESS;
+
+failed:
+       spin_unlock_bh(&session->lock);
+failed_unlocked:
+       ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
+                    task ? task->itt : 0);
+       mutex_unlock(&session->eh_mutex);
+       return FAILED;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_abort);
+
+static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
+{
+       memset(hdr, 0, sizeof(*hdr));
+       hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
+       hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
+       hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+       int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
+       hdr->rtt = RESERVED_ITT;
+}
+
+int iscsi_eh_device_reset(struct scsi_cmnd *sc)
+{
+       struct iscsi_cls_session *cls_session;
+       struct iscsi_session *session;
+       struct iscsi_conn *conn;
+       struct iscsi_tm *hdr;
+       int rc = FAILED;
+
+       cls_session = starget_to_session(scsi_target(sc->device));
+       session = cls_session->dd_data;
+
+       ISCSI_DBG_EH(session, "LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
+
+       mutex_lock(&session->eh_mutex);
+       spin_lock_bh(&session->lock);
+       /*
+        * Just check if we are not logged in. We cannot check for
+        * the phase because the reset could come from a ioctl.
+        */
+       if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
+               goto unlock;
+       conn = session->leadconn;
+
+       /* only have one tmf outstanding at a time */
+       if (conn->tmf_state != TMF_INITIAL)
+               goto unlock;
+       conn->tmf_state = TMF_QUEUED;
+
+       hdr = &conn->tmhdr;
+       iscsi_prep_lun_reset_pdu(sc, hdr);
+
+       if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
+                                   session->lu_reset_timeout)) {
+               rc = FAILED;
+               goto unlock;
+       }
+
+       switch (conn->tmf_state) {
+       case TMF_SUCCESS:
+               break;
+       case TMF_TIMEDOUT:
+               spin_unlock_bh(&session->lock);
+               iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+               goto done;
+       default:
+               conn->tmf_state = TMF_INITIAL;
+               goto unlock;
+       }
+
+       rc = SUCCESS;
+       spin_unlock_bh(&session->lock);
+
+       iscsi_suspend_tx(conn);
+
+       spin_lock_bh(&session->lock);
+       memset(hdr, 0, sizeof(*hdr));
+       fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
+       conn->tmf_state = TMF_INITIAL;
+       spin_unlock_bh(&session->lock);
+
+       iscsi_start_tx(conn);
+       goto done;
+
+unlock:
+       spin_unlock_bh(&session->lock);
+done:
+       ISCSI_DBG_EH(session, "dev reset result = %s\n",
+                    rc == SUCCESS ? "SUCCESS" : "FAILED");
+       mutex_unlock(&session->eh_mutex);
+       return rc;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
+
+void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
+{
+       struct iscsi_session *session = cls_session->dd_data;
 
-       if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
-               rc = FAILED;
-               goto failed;
+       spin_lock_bh(&session->lock);
+       if (session->state != ISCSI_STATE_LOGGED_IN) {
+               session->state = ISCSI_STATE_RECOVERY_FAILED;
+               if (session->leadconn)
+                       wake_up(&session->leadconn->ehwait);
        }
+       spin_unlock_bh(&session->lock);
+}
+EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 
-       switch (conn->tmf_state) {
-       case TMF_SUCCESS:
-               spin_unlock_bh(&session->lock);
-               iscsi_suspend_tx(conn);
-               /*
-                * clean up task if aborted. grab the recv lock as a writer
-                */
-               write_lock_bh(conn->recv_lock);
-               spin_lock(&session->lock);
-               fail_command(conn, ctask, DID_ABORT << 16);
-               conn->tmf_state = TMF_INITIAL;
-               spin_unlock(&session->lock);
-               write_unlock_bh(conn->recv_lock);
-               iscsi_start_tx(conn);
-               goto success_unlocked;
-       case TMF_TIMEDOUT:
+/**
+ * iscsi_eh_session_reset - drop session and attempt relogin
+ * @sc: scsi command
+ *
+ * This function will wait for a relogin, session termination from
+ * userspace, or a recovery/replacement timeout.
+ */
+int iscsi_eh_session_reset(struct scsi_cmnd *sc)
+{
+       struct iscsi_cls_session *cls_session;
+       struct iscsi_session *session;
+       struct iscsi_conn *conn;
+
+       cls_session = starget_to_session(scsi_target(sc->device));
+       session = cls_session->dd_data;
+       conn = session->leadconn;
+
+       mutex_lock(&session->eh_mutex);
+       spin_lock_bh(&session->lock);
+       if (session->state == ISCSI_STATE_TERMINATE) {
+failed:
+               ISCSI_DBG_EH(session,
+                            "failing session reset: Could not log back into "
+                            "%s, %s [age %d]\n", session->targetname,
+                            conn->persistent_address, session->age);
                spin_unlock_bh(&session->lock);
-               iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
-               goto failed_unlocked;
-       case TMF_NOT_FOUND:
-               if (!sc->SCp.ptr) {
-                       conn->tmf_state = TMF_INITIAL;
-                       /* ctask completed before tmf abort response */
-                       debug_scsi("sc completed while abort in progress\n");
-                       goto success;
-               }
-               /* fall through */
-       default:
-               conn->tmf_state = TMF_INITIAL;
-               goto failed;
+               mutex_unlock(&session->eh_mutex);
+               return FAILED;
        }
 
-success:
        spin_unlock_bh(&session->lock);
-success_unlocked:
-       debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
        mutex_unlock(&session->eh_mutex);
-       return SUCCESS;
+       /*
+        * we drop the lock here but the leadconn cannot be destoyed while
+        * we are in the scsi eh
+        */
+       iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 
-failed:
+       ISCSI_DBG_EH(session, "wait for relogin\n");
+       wait_event_interruptible(conn->ehwait,
+                                session->state == ISCSI_STATE_TERMINATE ||
+                                session->state == ISCSI_STATE_LOGGED_IN ||
+                                session->state == ISCSI_STATE_RECOVERY_FAILED);
+       if (signal_pending(current))
+               flush_signals(current);
+
+       mutex_lock(&session->eh_mutex);
+       spin_lock_bh(&session->lock);
+       if (session->state == ISCSI_STATE_LOGGED_IN) {
+               ISCSI_DBG_EH(session,
+                            "session reset succeeded for %s,%s\n",
+                            session->targetname, conn->persistent_address);
+       } else
+               goto failed;
        spin_unlock_bh(&session->lock);
-failed_unlocked:
-       debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
-                   ctask ? ctask->itt : 0);
        mutex_unlock(&session->eh_mutex);
-       return FAILED;
+       return SUCCESS;
 }
-EXPORT_SYMBOL_GPL(iscsi_eh_abort);
+EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
 
-static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
+static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
 {
        memset(hdr, 0, sizeof(*hdr));
        hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
-       hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
+       hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
        hdr->flags |= ISCSI_FLAG_CMD_FINAL;
-       int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
        hdr->rtt = RESERVED_ITT;
 }
 
-int iscsi_eh_device_reset(struct scsi_cmnd *sc)
+/**
+ * iscsi_eh_target_reset - reset target
+ * @sc: scsi command
+ *
+ * This will attempt to send a warm target reset.
+ */
+int iscsi_eh_target_reset(struct scsi_cmnd *sc)
 {
-       struct Scsi_Host *host = sc->device->host;
-       struct iscsi_session *session = iscsi_hostdata(host->hostdata);
+       struct iscsi_cls_session *cls_session;
+       struct iscsi_session *session;
        struct iscsi_conn *conn;
        struct iscsi_tm *hdr;
        int rc = FAILED;
 
-       debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
+       cls_session = starget_to_session(scsi_target(sc->device));
+       session = cls_session->dd_data;
+
+       ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
+                    session->targetname);
 
        mutex_lock(&session->eh_mutex);
        spin_lock_bh(&session->lock);
@@ -1537,10 +2437,10 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
        conn->tmf_state = TMF_QUEUED;
 
        hdr = &conn->tmhdr;
-       iscsi_prep_lun_reset_pdu(sc, hdr);
+       iscsi_prep_tgt_reset_pdu(sc, hdr);
 
        if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
-                                   session->lu_reset_timeout)) {
+                                   session->tgt_reset_timeout)) {
                rc = FAILED;
                goto unlock;
        }
@@ -1561,13 +2461,12 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
        spin_unlock_bh(&session->lock);
 
        iscsi_suspend_tx(conn);
-       /* need to grab the recv lock then session lock */
-       write_lock_bh(conn->recv_lock);
-       spin_lock(&session->lock);
-       fail_all_commands(conn, sc->device->lun);
+
+       spin_lock_bh(&session->lock);
+       memset(hdr, 0, sizeof(*hdr));
+       fail_scsi_tasks(conn, -1, DID_ERROR);
        conn->tmf_state = TMF_INITIAL;
-       spin_unlock(&session->lock);
-       write_unlock_bh(conn->recv_lock);
+       spin_unlock_bh(&session->lock);
 
        iscsi_start_tx(conn);
        goto done;
@@ -1575,12 +2474,30 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
 unlock:
        spin_unlock_bh(&session->lock);
 done:
-       debug_scsi("iscsi_eh_device_reset %s\n",
-                 rc == SUCCESS ? "SUCCESS" : "FAILED");
+       ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
+                    rc == SUCCESS ? "SUCCESS" : "FAILED");
        mutex_unlock(&session->eh_mutex);
        return rc;
 }
-EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
+EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
+
+/**
+ * iscsi_eh_recover_target - reset target and possibly the session
+ * @sc: scsi command
+ *
+ * This will attempt to send a warm target reset. If that fails,
+ * we will escalate to ERL0 session recovery.
+ */
+int iscsi_eh_recover_target(struct scsi_cmnd *sc)
+{
+       int rc;
+
+       rc = iscsi_eh_target_reset(sc);
+       if (rc == FAILED)
+               rc = iscsi_eh_session_reset(sc);
+       return rc;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
 
 /*
  * Pre-allocate a pool of @max items of @item_size. By default, the pool
@@ -1603,12 +2520,9 @@ iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
                num_arrays++;
        q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
        if (q->pool == NULL)
-               goto enomem;
+               return -ENOMEM;
 
-       q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
-                             GFP_KERNEL, NULL);
-       if (q->queue == ERR_PTR(-ENOMEM))
-               goto enomem;
+       kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
 
        for (i = 0; i < max; i++) {
                q->pool[i] = kzalloc(item_size, GFP_KERNEL);
@@ -1616,7 +2530,7 @@ iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
                        q->max = i;
                        goto enomem;
                }
-               __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
+               kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
        }
 
        if (items) {
@@ -1638,180 +2552,277 @@ void iscsi_pool_free(struct iscsi_pool *q)
 
        for (i = 0; i < q->max; i++)
                kfree(q->pool[i]);
-       if (q->pool)
-               kfree(q->pool);
+       kfree(q->pool);
 }
 EXPORT_SYMBOL_GPL(iscsi_pool_free);
 
-/*
- * iSCSI Session's hostdata organization:
+/**
+ * iscsi_host_add - add host to system
+ * @shost: scsi host
+ * @pdev: parent device
+ *
+ * This should be called by partial offload and software iscsi drivers
+ * to add a host to the system.
+ */
+int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
+{
+       if (!shost->can_queue)
+               shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
+
+       if (!shost->cmd_per_lun)
+               shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
+
+       if (!shost->transportt->eh_timed_out)
+               shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
+       return scsi_add_host(shost, pdev);
+}
+EXPORT_SYMBOL_GPL(iscsi_host_add);
+
+/**
+ * iscsi_host_alloc - allocate a host and driver data
+ * @sht: scsi host template
+ * @dd_data_size: driver host data size
+ * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
+ *
+ * This should be called by partial offload and software iscsi drivers.
+ * To access the driver specific memory use the iscsi_host_priv() macro.
+ */
+struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
+                                  int dd_data_size, bool xmit_can_sleep)
+{
+       struct Scsi_Host *shost;
+       struct iscsi_host *ihost;
+
+       shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
+       if (!shost)
+               return NULL;
+       ihost = shost_priv(shost);
+
+       if (xmit_can_sleep) {
+               snprintf(ihost->workq_name, sizeof(ihost->workq_name),
+                       "iscsi_q_%d", shost->host_no);
+               ihost->workq = create_singlethread_workqueue(ihost->workq_name);
+               if (!ihost->workq)
+                       goto free_host;
+       }
+
+       spin_lock_init(&ihost->lock);
+       ihost->state = ISCSI_HOST_SETUP;
+       ihost->num_sessions = 0;
+       init_waitqueue_head(&ihost->session_removal_wq);
+       return shost;
+
+free_host:
+       scsi_host_put(shost);
+       return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_host_alloc);
+
+static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
+{
+       iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
+}
+
+/**
+ * iscsi_host_remove - remove host and sessions
+ * @shost: scsi host
  *
- *    *------------------* <== hostdata_session(host->hostdata)
- *    | ptr to class sess|
- *    |------------------| <== iscsi_hostdata(host->hostdata)
- *    | iscsi_session    |
- *    *------------------*
+ * If there are any sessions left, this will initiate the removal and wait
+ * for the completion.
  */
+void iscsi_host_remove(struct Scsi_Host *shost)
+{
+       struct iscsi_host *ihost = shost_priv(shost);
+       unsigned long flags;
+
+       spin_lock_irqsave(&ihost->lock, flags);
+       ihost->state = ISCSI_HOST_REMOVED;
+       spin_unlock_irqrestore(&ihost->lock, flags);
+
+       iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
+       wait_event_interruptible(ihost->session_removal_wq,
+                                ihost->num_sessions == 0);
+       if (signal_pending(current))
+               flush_signals(current);
+
+       scsi_remove_host(shost);
+       if (ihost->workq)
+               destroy_workqueue(ihost->workq);
+}
+EXPORT_SYMBOL_GPL(iscsi_host_remove);
 
-#define hostdata_privsize(_sz) (sizeof(unsigned long) + _sz + \
-                                _sz % sizeof(unsigned long))
+void iscsi_host_free(struct Scsi_Host *shost)
+{
+       struct iscsi_host *ihost = shost_priv(shost);
+
+       kfree(ihost->netdev);
+       kfree(ihost->hwaddress);
+       kfree(ihost->initiatorname);
+       scsi_host_put(shost);
+}
+EXPORT_SYMBOL_GPL(iscsi_host_free);
+
+static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
+{
+       struct iscsi_host *ihost = shost_priv(shost);
+       unsigned long flags;
+
+       shost = scsi_host_get(shost);
+       if (!shost) {
+               printk(KERN_ERR "Invalid state. Cannot notify host removal "
+                     "of session teardown event because host already "
+                     "removed.\n");
+               return;
+       }
 
-#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
+       spin_lock_irqsave(&ihost->lock, flags);
+       ihost->num_sessions--;
+       if (ihost->num_sessions == 0)
+               wake_up(&ihost->session_removal_wq);
+       spin_unlock_irqrestore(&ihost->lock, flags);
+       scsi_host_put(shost);
+}
 
 /**
  * iscsi_session_setup - create iscsi cls session and host and session
- * @scsit: scsi transport template
  * @iscsit: iscsi transport template
- * @cmds_max: scsi host can queue
- * @qdepth: scsi host cmds per lun
- * @cmd_task_size: LLD ctask private data size
- * @mgmt_task_size: LLD mtask private data size
+ * @shost: scsi host
+ * @cmds_max: session can queue
+ * @cmd_task_size: LLD task private data size
  * @initial_cmdsn: initial CmdSN
- * @hostno: host no allocated
  *
  * This can be used by software iscsi_transports that allocate
  * a session per scsi host.
- **/
+ *
+ * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
+ * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
+ * for nop handling and login/logout requests.
+ */
 struct iscsi_cls_session *
-iscsi_session_setup(struct iscsi_transport *iscsit,
-                   struct scsi_transport_template *scsit,
-                   uint16_t cmds_max, uint16_t qdepth,
-                   int cmd_task_size, int mgmt_task_size,
-                   uint32_t initial_cmdsn, uint32_t *hostno)
+iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
+                   uint16_t cmds_max, int dd_size, int cmd_task_size,
+                   uint32_t initial_cmdsn, unsigned int id)
 {
-       struct Scsi_Host *shost;
+       struct iscsi_host *ihost = shost_priv(shost);
        struct iscsi_session *session;
        struct iscsi_cls_session *cls_session;
-       int cmd_i;
+       int cmd_i, scsi_cmds, total_cmds = cmds_max;
+       unsigned long flags;
+
+       spin_lock_irqsave(&ihost->lock, flags);
+       if (ihost->state == ISCSI_HOST_REMOVED) {
+               spin_unlock_irqrestore(&ihost->lock, flags);
+               return NULL;
+       }
+       ihost->num_sessions++;
+       spin_unlock_irqrestore(&ihost->lock, flags);
 
-       if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
-               if (qdepth != 0)
-                       printk(KERN_ERR "iscsi: invalid queue depth of %d. "
-                             "Queue depth must be between 1 and %d.\n",
-                             qdepth, ISCSI_MAX_CMD_PER_LUN);
-               qdepth = ISCSI_DEF_CMD_PER_LUN;
+       if (!total_cmds)
+               total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
+       /*
+        * The iscsi layer needs some tasks for nop handling and tmfs,
+        * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
+        * + 1 command for scsi IO.
+        */
+       if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
+               printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
+                      "must be a power of two that is at least %d.\n",
+                      total_cmds, ISCSI_TOTAL_CMDS_MIN);
+               goto dec_session_count;
        }
 
-       if (cmds_max < 2 || (cmds_max & (cmds_max - 1)) ||
-           cmds_max >= ISCSI_MGMT_ITT_OFFSET) {
-               if (cmds_max != 0)
-                       printk(KERN_ERR "iscsi: invalid can_queue of %d. "
-                              "can_queue must be a power of 2 and between "
-                              "2 and %d - setting to %d.\n", cmds_max,
-                              ISCSI_MGMT_ITT_OFFSET, ISCSI_DEF_XMIT_CMDS_MAX);
-               cmds_max = ISCSI_DEF_XMIT_CMDS_MAX;
+       if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
+               printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
+                      "must be a power of 2 less than or equal to %d.\n",
+                      cmds_max, ISCSI_TOTAL_CMDS_MAX);
+               total_cmds = ISCSI_TOTAL_CMDS_MAX;
        }
 
-       shost = scsi_host_alloc(iscsit->host_template,
-                               hostdata_privsize(sizeof(*session)));
-       if (!shost)
-               return NULL;
+       if (!is_power_of_2(total_cmds)) {
+               printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
+                      "must be a power of 2.\n", total_cmds);
+               total_cmds = rounddown_pow_of_two(total_cmds);
+               if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
+                       return NULL;
+               printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
+                      total_cmds);
+       }
+       scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
 
-       /* the iscsi layer takes one task for reserve */
-       shost->can_queue = cmds_max - 1;
-       shost->cmd_per_lun = qdepth;
-       shost->max_id = 1;
-       shost->max_channel = 0;
-       shost->max_lun = iscsit->max_lun;
-       shost->max_cmd_len = iscsit->max_cmd_len;
-       shost->transportt = scsit;
-       shost->transportt->create_work_queue = 1;
-       shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
-       *hostno = shost->host_no;
-
-       session = iscsi_hostdata(shost->hostdata);
-       memset(session, 0, sizeof(struct iscsi_session));
+       cls_session = iscsi_alloc_session(shost, iscsit,
+                                         sizeof(struct iscsi_session) +
+                                         dd_size);
+       if (!cls_session)
+               goto dec_session_count;
+       session = cls_session->dd_data;
+       session->cls_session = cls_session;
        session->host = shost;
        session->state = ISCSI_STATE_FREE;
        session->fast_abort = 1;
-       session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
-       session->cmds_max = cmds_max;
+       session->tgt_reset_timeout = 30;
+       session->lu_reset_timeout = 15;
+       session->abort_timeout = 10;
+       session->scsi_cmds_max = scsi_cmds;
+       session->cmds_max = total_cmds;
        session->queued_cmdsn = session->cmdsn = initial_cmdsn;
        session->exp_cmdsn = initial_cmdsn + 1;
        session->max_cmdsn = initial_cmdsn + 1;
        session->max_r2t = 1;
        session->tt = iscsit;
+       session->dd_data = cls_session->dd_data + sizeof(*session);
        mutex_init(&session->eh_mutex);
+       spin_lock_init(&session->lock);
 
        /* initialize SCSI PDU commands pool */
        if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
                            (void***)&session->cmds,
-                           cmd_task_size + sizeof(struct iscsi_cmd_task)))
+                           cmd_task_size + sizeof(struct iscsi_task)))
                goto cmdpool_alloc_fail;
 
        /* pre-format cmds pool with ITT */
        for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
-               struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
+               struct iscsi_task *task = session->cmds[cmd_i];
 
                if (cmd_task_size)
-                       ctask->dd_data = &ctask[1];
-               ctask->itt = cmd_i;
-               INIT_LIST_HEAD(&ctask->running);
-       }
-
-       spin_lock_init(&session->lock);
-
-       /* initialize immediate command pool */
-       if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
-                          (void***)&session->mgmt_cmds,
-                          mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
-               goto mgmtpool_alloc_fail;
-
-
-       /* pre-format immediate cmds pool with ITT */
-       for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
-               struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
-
-               if (mgmt_task_size)
-                       mtask->dd_data = &mtask[1];
-               mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
-               INIT_LIST_HEAD(&mtask->running);
+                       task->dd_data = &task[1];
+               task->itt = cmd_i;
+               task->state = ISCSI_TASK_FREE;
+               INIT_LIST_HEAD(&task->running);
        }
 
-       if (scsi_add_host(shost, NULL))
-               goto add_host_fail;
-
        if (!try_module_get(iscsit->owner))
-               goto cls_session_fail;
+               goto module_get_fail;
 
-       cls_session = iscsi_create_session(shost, iscsit, 0);
-       if (!cls_session)
-               goto module_put;
-       *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
+       if (iscsi_add_session(cls_session, id))
+               goto cls_session_fail;
 
        return cls_session;
 
-module_put:
-       module_put(iscsit->owner);
 cls_session_fail:
-       scsi_remove_host(shost);
-add_host_fail:
-       iscsi_pool_free(&session->mgmtpool);
-mgmtpool_alloc_fail:
+       module_put(iscsit->owner);
+module_get_fail:
        iscsi_pool_free(&session->cmdpool);
 cmdpool_alloc_fail:
-       scsi_host_put(shost);
+       iscsi_free_session(cls_session);
+dec_session_count:
+       iscsi_host_dec_session_cnt(shost);
        return NULL;
 }
 EXPORT_SYMBOL_GPL(iscsi_session_setup);
 
 /**
  * iscsi_session_teardown - destroy session, host, and cls_session
- * shost: scsi host
+ * @cls_session: iscsi session
  *
- * This can be used by software iscsi_transports that allocate
- * a session per scsi host.
- **/
+ * The driver must have called iscsi_remove_session before
+ * calling this.
+ */
 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
 {
-       struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
-       struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+       struct iscsi_session *session = cls_session->dd_data;
        struct module *owner = cls_session->transport->owner;
+       struct Scsi_Host *shost = session->host;
 
-       iscsi_remove_session(cls_session);
-       scsi_remove_host(shost);
-
-       iscsi_pool_free(&session->mgmtpool);
        iscsi_pool_free(&session->cmdpool);
 
        kfree(session->password);
@@ -1819,12 +2830,11 @@ void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
        kfree(session->username);
        kfree(session->username_in);
        kfree(session->targetname);
-       kfree(session->netdev);
-       kfree(session->hwaddress);
        kfree(session->initiatorname);
+       kfree(session->ifacename);
 
-       iscsi_free_session(cls_session);
-       scsi_host_put(shost);
+       iscsi_destroy_session(cls_session);
+       iscsi_host_dec_session_cnt(shost);
        module_put(owner);
 }
 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
@@ -1832,22 +2842,26 @@ EXPORT_SYMBOL_GPL(iscsi_session_teardown);
 /**
  * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
  * @cls_session: iscsi_cls_session
+ * @dd_size: private driver data size
  * @conn_idx: cid
- **/
+ */
 struct iscsi_cls_conn *
-iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
+iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
+                uint32_t conn_idx)
 {
-       struct iscsi_session *session = class_to_transport_session(cls_session);
+       struct iscsi_session *session = cls_session->dd_data;
        struct iscsi_conn *conn;
        struct iscsi_cls_conn *cls_conn;
        char *data;
 
-       cls_conn = iscsi_create_conn(cls_session, conn_idx);
+       cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
+                                    conn_idx);
        if (!cls_conn)
                return NULL;
        conn = cls_conn->dd_data;
-       memset(conn, 0, sizeof(*conn));
+       memset(conn, 0, sizeof(*conn) + dd_size);
 
+       conn->dd_data = cls_conn->dd_data + sizeof(*conn);
        conn->session = session;
        conn->cls_conn = cls_conn;
        conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
@@ -1859,37 +2873,36 @@ iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
        conn->transport_timer.data = (unsigned long)conn;
        conn->transport_timer.function = iscsi_check_transport_timeouts;
 
-       INIT_LIST_HEAD(&conn->run_list);
-       INIT_LIST_HEAD(&conn->mgmt_run_list);
        INIT_LIST_HEAD(&conn->mgmtqueue);
-       INIT_LIST_HEAD(&conn->xmitqueue);
+       INIT_LIST_HEAD(&conn->cmdqueue);
        INIT_LIST_HEAD(&conn->requeue);
        INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
 
-       /* allocate login_mtask used for the login/text sequences */
+       /* allocate login_task used for the login/text sequences */
        spin_lock_bh(&session->lock);
-       if (!__kfifo_get(session->mgmtpool.queue,
-                         (void*)&conn->login_mtask,
+       if (!kfifo_out(&session->cmdpool.queue,
+                         (void*)&conn->login_task,
                         sizeof(void*))) {
                spin_unlock_bh(&session->lock);
-               goto login_mtask_alloc_fail;
+               goto login_task_alloc_fail;
        }
        spin_unlock_bh(&session->lock);
 
-       data = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
+       data = (char *) __get_free_pages(GFP_KERNEL,
+                                        get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
        if (!data)
-               goto login_mtask_data_alloc_fail;
-       conn->login_mtask->data = conn->data = data;
+               goto login_task_data_alloc_fail;
+       conn->login_task->data = conn->data = data;
 
        init_timer(&conn->tmf_timer);
        init_waitqueue_head(&conn->ehwait);
 
        return cls_conn;
 
-login_mtask_data_alloc_fail:
-       __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+login_task_data_alloc_fail:
+       kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
                    sizeof(void*));
-login_mtask_alloc_fail:
+login_task_alloc_fail:
        iscsi_destroy_conn(cls_conn);
        return NULL;
 }
@@ -1933,9 +2946,10 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
                }
                spin_unlock_irqrestore(session->host->host_lock, flags);
                msleep_interruptible(500);
-               printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
-                      "host_failed %d\n", session->host->host_busy,
-                      session->host->host_failed);
+               iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
+                                 "host_busy %d host_failed %d\n",
+                                 session->host->host_busy,
+                                 session->host->host_failed);
                /*
                 * force eh_abort() to unblock
                 */
@@ -1946,9 +2960,10 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
        iscsi_suspend_tx(conn);
 
        spin_lock_bh(&session->lock);
-       kfree(conn->data);
+       free_pages((unsigned long) conn->data,
+                  get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
        kfree(conn->persistent_address);
-       __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+       kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
                    sizeof(void*));
        if (session->leadconn == conn)
                session->leadconn = NULL;
@@ -1964,27 +2979,28 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
        struct iscsi_session *session = conn->session;
 
        if (!session) {
-               printk(KERN_ERR "iscsi: can't start unbound connection\n");
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "can't start unbound connection\n");
                return -EPERM;
        }
 
        if ((session->imm_data_en || !session->initial_r2t_en) &&
             session->first_burst > session->max_burst) {
-               printk("iscsi: invalid burst lengths: "
-                      "first_burst %d max_burst %d\n",
-                      session->first_burst, session->max_burst);
+               iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
+                                 "first_burst %d max_burst %d\n",
+                                 session->first_burst, session->max_burst);
                return -EINVAL;
        }
 
        if (conn->ping_timeout && !conn->recv_timeout) {
-               printk(KERN_ERR "iscsi: invalid recv timeout of zero "
-                     "Using 5 seconds\n.");
+               iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
+                                 "zero. Using 5 seconds\n.");
                conn->recv_timeout = 5;
        }
 
        if (conn->recv_timeout && !conn->ping_timeout) {
-               printk(KERN_ERR "iscsi: invalid ping timeout of zero "
-                     "Using 5 seconds.\n");
+               iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
+                                 "zero. Using 5 seconds.\n");
                conn->ping_timeout = 5;
        }
 
@@ -2008,11 +3024,9 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
                conn->stop_stage = 0;
                conn->tmf_state = TMF_INITIAL;
                session->age++;
-               spin_unlock_bh(&session->lock);
-
-               iscsi_unblock_session(session_to_cls(session));
-               wake_up(&conn->ehwait);
-               return 0;
+               if (session->age == 16)
+                       session->age = 0;
+               break;
        case STOP_CONN_TERM:
                conn->stop_stage = 0;
                break;
@@ -2021,28 +3035,35 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
        }
        spin_unlock_bh(&session->lock);
 
+       iscsi_unblock_session(session->cls_session);
+       wake_up(&conn->ehwait);
        return 0;
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_start);
 
 static void
-flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
+fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
 {
-       struct iscsi_mgmt_task *mtask, *tmp;
+       struct iscsi_task *task;
+       int i, state;
 
-       /* handle pending */
-       list_for_each_entry_safe(mtask, tmp, &conn->mgmtqueue, running) {
-               debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
-               iscsi_free_mgmt_task(conn, mtask);
-       }
+       for (i = 0; i < conn->session->cmds_max; i++) {
+               task = conn->session->cmds[i];
+               if (task->sc)
+                       continue;
 
-       /* handle running */
-       list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
-               debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
-               iscsi_free_mgmt_task(conn, mtask);
-       }
+               if (task->state == ISCSI_TASK_FREE)
+                       continue;
 
-       conn->mtask = NULL;
+               ISCSI_DBG_SESSION(conn->session,
+                                 "failing mgmt itt 0x%x state %d\n",
+                                 task->itt, task->state);
+               state = ISCSI_TASK_ABRT_SESS_RECOV;
+               if (task->state == ISCSI_TASK_PENDING)
+                       state = ISCSI_TASK_COMPLETED;
+               iscsi_complete_task(task, state);
+
+       }
 }
 
 static void iscsi_start_session_recovery(struct iscsi_session *session,
@@ -2050,8 +3071,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
 {
        int old_stop_stage;
 
-       del_timer_sync(&conn->transport_timer);
-
        mutex_lock(&session->eh_mutex);
        spin_lock_bh(&session->lock);
        if (conn->stop_stage == STOP_CONN_TERM) {
@@ -2061,17 +3080,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
        }
 
        /*
-        * The LLD either freed/unset the lock on us, or userspace called
-        * stop but did not create a proper connection (connection was never
-        * bound or it was unbound then stop was called).
-        */
-       if (!conn->recv_lock) {
-               spin_unlock_bh(&session->lock);
-               mutex_unlock(&session->eh_mutex);
-               return;
-       }
-
-       /*
         * When this is called for the in_login state, we only want to clean
         * up the login task and connection. We do not need to block and set
         * the recovery state again
@@ -2083,14 +3091,14 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
 
        old_stop_stage = conn->stop_stage;
        conn->stop_stage = flag;
-       conn->c_stage = ISCSI_CONN_STOPPED;
        spin_unlock_bh(&session->lock);
 
+       del_timer_sync(&conn->transport_timer);
        iscsi_suspend_tx(conn);
 
-       write_lock_bh(conn->recv_lock);
-       set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
-       write_unlock_bh(conn->recv_lock);
+       spin_lock_bh(&session->lock);
+       conn->c_stage = ISCSI_CONN_STOPPED;
+       spin_unlock_bh(&session->lock);
 
        /*
         * for connection level recovery we should not calculate
@@ -2103,8 +3111,8 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
                conn->datadgst_en = 0;
                if (session->state == ISCSI_STATE_IN_RECOVERY &&
                    old_stop_stage != STOP_CONN_RECOVER) {
-                       debug_scsi("blocking session\n");
-                       iscsi_block_session(session_to_cls(session));
+                       ISCSI_DBG_SESSION(session, "blocking session\n");
+                       iscsi_block_session(session->cls_session);
                }
        }
 
@@ -2112,8 +3120,9 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
         * flush queues.
         */
        spin_lock_bh(&session->lock);
-       fail_all_commands(conn, -1);
-       flush_control_queues(session, conn);
+       fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
+       fail_mgmt_tasks(session, conn);
+       memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
        spin_unlock_bh(&session->lock);
        mutex_unlock(&session->eh_mutex);
 }
@@ -2129,7 +3138,8 @@ void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
                iscsi_start_session_recovery(session, conn, flag);
                break;
        default:
-               printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
+               iscsi_conn_printk(KERN_ERR, conn,
+                                 "invalid stop flag %d\n", flag);
        }
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
@@ -2137,7 +3147,7 @@ EXPORT_SYMBOL_GPL(iscsi_conn_stop);
 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
                    struct iscsi_cls_conn *cls_conn, int is_leading)
 {
-       struct iscsi_session *session = class_to_transport_session(cls_session);
+       struct iscsi_session *session = cls_session->dd_data;
        struct iscsi_conn *conn = cls_conn->dd_data;
 
        spin_lock_bh(&session->lock);
@@ -2154,6 +3164,23 @@ int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
 
+static int iscsi_switch_str_param(char **param, char *new_val_buf)
+{
+       char *new_val;
+
+       if (*param) {
+               if (!strcmp(*param, new_val_buf))
+                       return 0;
+       }
+
+       new_val = kstrdup(new_val_buf, GFP_NOIO);
+       if (!new_val)
+               return -ENOMEM;
+
+       kfree(*param);
+       *param = new_val;
+       return 0;
+}
 
 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
                    enum iscsi_param param, char *buf, int buflen)
@@ -2172,6 +3199,9 @@ int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
        case ISCSI_PARAM_LU_RESET_TMO:
                sscanf(buf, "%d", &session->lu_reset_timeout);
                break;
+       case ISCSI_PARAM_TGT_RESET_TMO:
+               sscanf(buf, "%d", &session->tgt_reset_timeout);
+               break;
        case ISCSI_PARAM_PING_TMO:
                sscanf(buf, "%d", &conn->ping_timeout);
                break;
@@ -2226,38 +3256,15 @@ int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
                sscanf(buf, "%u", &conn->exp_statsn);
                break;
        case ISCSI_PARAM_USERNAME:
-               kfree(session->username);
-               session->username = kstrdup(buf, GFP_KERNEL);
-               if (!session->username)
-                       return -ENOMEM;
-               break;
+               return iscsi_switch_str_param(&session->username, buf);
        case ISCSI_PARAM_USERNAME_IN:
-               kfree(session->username_in);
-               session->username_in = kstrdup(buf, GFP_KERNEL);
-               if (!session->username_in)
-                       return -ENOMEM;
-               break;
+               return iscsi_switch_str_param(&session->username_in, buf);
        case ISCSI_PARAM_PASSWORD:
-               kfree(session->password);
-               session->password = kstrdup(buf, GFP_KERNEL);
-               if (!session->password)
-                       return -ENOMEM;
-               break;
+               return iscsi_switch_str_param(&session->password, buf);
        case ISCSI_PARAM_PASSWORD_IN:
-               kfree(session->password_in);
-               session->password_in = kstrdup(buf, GFP_KERNEL);
-               if (!session->password_in)
-                       return -ENOMEM;
-               break;
+               return iscsi_switch_str_param(&session->password_in, buf);
        case ISCSI_PARAM_TARGET_NAME:
-               /* this should not change between logins */
-               if (session->targetname)
-                       break;
-
-               session->targetname = kstrdup(buf, GFP_KERNEL);
-               if (!session->targetname)
-                       return -ENOMEM;
-               break;
+               return iscsi_switch_str_param(&session->targetname, buf);
        case ISCSI_PARAM_TPGT:
                sscanf(buf, "%d", &session->tpgt);
                break;
@@ -2265,17 +3272,11 @@ int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
                sscanf(buf, "%d", &conn->persistent_port);
                break;
        case ISCSI_PARAM_PERSISTENT_ADDRESS:
-               /*
-                * this is the address returned in discovery so it should
-                * not change between logins.
-                */
-               if (conn->persistent_address)
-                       break;
-
-               conn->persistent_address = kstrdup(buf, GFP_KERNEL);
-               if (!conn->persistent_address)
-                       return -ENOMEM;
-               break;
+               return iscsi_switch_str_param(&conn->persistent_address, buf);
+       case ISCSI_PARAM_IFACE_NAME:
+               return iscsi_switch_str_param(&session->ifacename, buf);
+       case ISCSI_PARAM_INITIATOR_NAME:
+               return iscsi_switch_str_param(&session->initiatorname, buf);
        default:
                return -ENOSYS;
        }
@@ -2287,8 +3288,7 @@ EXPORT_SYMBOL_GPL(iscsi_set_param);
 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
                            enum iscsi_param param, char *buf)
 {
-       struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
-       struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+       struct iscsi_session *session = cls_session->dd_data;
        int len;
 
        switch(param) {
@@ -2301,6 +3301,9 @@ int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
        case ISCSI_PARAM_LU_RESET_TMO:
                len = sprintf(buf, "%d\n", session->lu_reset_timeout);
                break;
+       case ISCSI_PARAM_TGT_RESET_TMO:
+               len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
+               break;
        case ISCSI_PARAM_INITIAL_R2T_EN:
                len = sprintf(buf, "%d\n", session->initial_r2t_en);
                break;
@@ -2343,6 +3346,12 @@ int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
        case ISCSI_PARAM_PASSWORD_IN:
                len = sprintf(buf, "%s\n", session->password_in);
                break;
+       case ISCSI_PARAM_IFACE_NAME:
+               len = sprintf(buf, "%s\n", session->ifacename);
+               break;
+       case ISCSI_PARAM_INITIATOR_NAME:
+               len = sprintf(buf, "%s\n", session->initiatorname);
+               break;
        default:
                return -ENOSYS;
        }
@@ -2402,29 +3411,22 @@ EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
                         char *buf)
 {
-       struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+       struct iscsi_host *ihost = shost_priv(shost);
        int len;
 
        switch (param) {
        case ISCSI_HOST_PARAM_NETDEV_NAME:
-               if (!session->netdev)
-                       len = sprintf(buf, "%s\n", "default");
-               else
-                       len = sprintf(buf, "%s\n", session->netdev);
+               len = sprintf(buf, "%s\n", ihost->netdev);
                break;
        case ISCSI_HOST_PARAM_HWADDRESS:
-               if (!session->hwaddress)
-                       len = sprintf(buf, "%s\n", "default");
-               else
-                       len = sprintf(buf, "%s\n", session->hwaddress);
+               len = sprintf(buf, "%s\n", ihost->hwaddress);
                break;
        case ISCSI_HOST_PARAM_INITIATOR_NAME:
-               if (!session->initiatorname)
-                       len = sprintf(buf, "%s\n", "unknown");
-               else
-                       len = sprintf(buf, "%s\n", session->initiatorname);
+               len = sprintf(buf, "%s\n", ihost->initiatorname);
+               break;
+       case ISCSI_HOST_PARAM_IPADDRESS:
+               len = sprintf(buf, "%s\n", ihost->local_address);
                break;
-
        default:
                return -ENOSYS;
        }
@@ -2436,21 +3438,15 @@ EXPORT_SYMBOL_GPL(iscsi_host_get_param);
 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
                         char *buf, int buflen)
 {
-       struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+       struct iscsi_host *ihost = shost_priv(shost);
 
        switch (param) {
        case ISCSI_HOST_PARAM_NETDEV_NAME:
-               if (!session->netdev)
-                       session->netdev = kstrdup(buf, GFP_KERNEL);
-               break;
+               return iscsi_switch_str_param(&ihost->netdev, buf);
        case ISCSI_HOST_PARAM_HWADDRESS:
-               if (!session->hwaddress)
-                       session->hwaddress = kstrdup(buf, GFP_KERNEL);
-               break;
+               return iscsi_switch_str_param(&ihost->hwaddress, buf);
        case ISCSI_HOST_PARAM_INITIATOR_NAME:
-               if (!session->initiatorname)
-                       session->initiatorname = kstrdup(buf, GFP_KERNEL);
-               break;
+               return iscsi_switch_str_param(&ihost->initiatorname, buf);
        default:
                return -ENOSYS;
        }