Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad...
[pandora-kernel.git] / drivers / target / target_core_transport.c
index 8d0c58e..0257658 100644 (file)
@@ -26,7 +26,6 @@
  *
  ******************************************************************************/
 
-#include <linux/version.h>
 #include <linux/net.h>
 #include <linux/delay.h>
 #include <linux/string.h>
@@ -37,6 +36,7 @@
 #include <linux/kthread.h>
 #include <linux/in.h>
 #include <linux/cdrom.h>
+#include <linux/module.h>
 #include <asm/unaligned.h>
 #include <net/sock.h>
 #include <net/tcp.h>
 #include <target/target_core_configfs.h>
 
 #include "target_core_alua.h"
+#include "target_core_cdb.h"
 #include "target_core_hba.h"
 #include "target_core_pr.h"
-#include "target_core_scdb.h"
 #include "target_core_ua.h"
 
 static int sub_api_initialized;
 
-static struct kmem_cache *se_cmd_cache;
+static struct workqueue_struct *target_completion_wq;
 static struct kmem_cache *se_sess_cache;
 struct kmem_cache *se_tmr_req_cache;
 struct kmem_cache *se_ua_cache;
@@ -70,39 +70,22 @@ struct kmem_cache *t10_alua_lu_gp_mem_cache;
 struct kmem_cache *t10_alua_tg_pt_gp_cache;
 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
 
-/* Used for transport_dev_get_map_*() */
-typedef int (*map_func_t)(struct se_task *, u32);
-
 static int transport_generic_write_pending(struct se_cmd *);
 static int transport_processing_thread(void *param);
 static int __transport_execute_tasks(struct se_device *dev);
 static void transport_complete_task_attr(struct se_cmd *cmd);
-static int transport_complete_qf(struct se_cmd *cmd);
 static void transport_handle_queue_full(struct se_cmd *cmd,
-               struct se_device *dev, int (*qf_callback)(struct se_cmd *));
-static void transport_direct_request_timeout(struct se_cmd *cmd);
+               struct se_device *dev);
 static void transport_free_dev_tasks(struct se_cmd *cmd);
-static u32 transport_allocate_tasks(struct se_cmd *cmd,
-               unsigned long long starting_lba,
-               enum dma_data_direction data_direction,
-               struct scatterlist *sgl, unsigned int nents);
 static int transport_generic_get_mem(struct se_cmd *cmd);
-static int transport_generic_remove(struct se_cmd *cmd,
-               int session_reinstatement);
-static void transport_release_fe_cmd(struct se_cmd *cmd);
-static void transport_remove_cmd_from_queue(struct se_cmd *cmd,
-               struct se_queue_obj *qobj);
+static void transport_put_cmd(struct se_cmd *cmd);
+static void transport_remove_cmd_from_queue(struct se_cmd *cmd);
 static int transport_set_sense_codes(struct se_cmd *cmd, u8 asc, u8 ascq);
-static void transport_stop_all_task_timers(struct se_cmd *cmd);
+static void transport_generic_request_failure(struct se_cmd *);
+static void target_complete_ok_work(struct work_struct *work);
 
 int init_se_kmem_caches(void)
 {
-       se_cmd_cache = kmem_cache_create("se_cmd_cache",
-                       sizeof(struct se_cmd), __alignof__(struct se_cmd), 0, NULL);
-       if (!se_cmd_cache) {
-               pr_err("kmem_cache_create for struct se_cmd failed\n");
-               goto out;
-       }
        se_tmr_req_cache = kmem_cache_create("se_tmr_cache",
                        sizeof(struct se_tmr_req), __alignof__(struct se_tmr_req),
                        0, NULL);
@@ -117,14 +100,14 @@ int init_se_kmem_caches(void)
        if (!se_sess_cache) {
                pr_err("kmem_cache_create() for struct se_session"
                                " failed\n");
-               goto out;
+               goto out_free_tmr_req_cache;
        }
        se_ua_cache = kmem_cache_create("se_ua_cache",
                        sizeof(struct se_ua), __alignof__(struct se_ua),
                        0, NULL);
        if (!se_ua_cache) {
                pr_err("kmem_cache_create() for struct se_ua failed\n");
-               goto out;
+               goto out_free_sess_cache;
        }
        t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
                        sizeof(struct t10_pr_registration),
@@ -132,7 +115,7 @@ int init_se_kmem_caches(void)
        if (!t10_pr_reg_cache) {
                pr_err("kmem_cache_create() for struct t10_pr_registration"
                                " failed\n");
-               goto out;
+               goto out_free_ua_cache;
        }
        t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
                        sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
@@ -140,7 +123,7 @@ int init_se_kmem_caches(void)
        if (!t10_alua_lu_gp_cache) {
                pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
                                " failed\n");
-               goto out;
+               goto out_free_pr_reg_cache;
        }
        t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
                        sizeof(struct t10_alua_lu_gp_member),
@@ -148,7 +131,7 @@ int init_se_kmem_caches(void)
        if (!t10_alua_lu_gp_mem_cache) {
                pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
                                "cache failed\n");
-               goto out;
+               goto out_free_lu_gp_cache;
        }
        t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
                        sizeof(struct t10_alua_tg_pt_gp),
@@ -156,7 +139,7 @@ int init_se_kmem_caches(void)
        if (!t10_alua_tg_pt_gp_cache) {
                pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
                                "cache failed\n");
-               goto out;
+               goto out_free_lu_gp_mem_cache;
        }
        t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
                        "t10_alua_tg_pt_gp_mem_cache",
@@ -166,35 +149,39 @@ int init_se_kmem_caches(void)
        if (!t10_alua_tg_pt_gp_mem_cache) {
                pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
                                "mem_t failed\n");
-               goto out;
+               goto out_free_tg_pt_gp_cache;
        }
 
+       target_completion_wq = alloc_workqueue("target_completion",
+                                              WQ_MEM_RECLAIM, 0);
+       if (!target_completion_wq)
+               goto out_free_tg_pt_gp_mem_cache;
+
        return 0;
+
+out_free_tg_pt_gp_mem_cache:
+       kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
+out_free_tg_pt_gp_cache:
+       kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
+out_free_lu_gp_mem_cache:
+       kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
+out_free_lu_gp_cache:
+       kmem_cache_destroy(t10_alua_lu_gp_cache);
+out_free_pr_reg_cache:
+       kmem_cache_destroy(t10_pr_reg_cache);
+out_free_ua_cache:
+       kmem_cache_destroy(se_ua_cache);
+out_free_sess_cache:
+       kmem_cache_destroy(se_sess_cache);
+out_free_tmr_req_cache:
+       kmem_cache_destroy(se_tmr_req_cache);
 out:
-       if (se_cmd_cache)
-               kmem_cache_destroy(se_cmd_cache);
-       if (se_tmr_req_cache)
-               kmem_cache_destroy(se_tmr_req_cache);
-       if (se_sess_cache)
-               kmem_cache_destroy(se_sess_cache);
-       if (se_ua_cache)
-               kmem_cache_destroy(se_ua_cache);
-       if (t10_pr_reg_cache)
-               kmem_cache_destroy(t10_pr_reg_cache);
-       if (t10_alua_lu_gp_cache)
-               kmem_cache_destroy(t10_alua_lu_gp_cache);
-       if (t10_alua_lu_gp_mem_cache)
-               kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
-       if (t10_alua_tg_pt_gp_cache)
-               kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
-       if (t10_alua_tg_pt_gp_mem_cache)
-               kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
        return -ENOMEM;
 }
 
 void release_se_kmem_caches(void)
 {
-       kmem_cache_destroy(se_cmd_cache);
+       destroy_workqueue(target_completion_wq);
        kmem_cache_destroy(se_tmr_req_cache);
        kmem_cache_destroy(se_sess_cache);
        kmem_cache_destroy(se_ua_cache);
@@ -234,10 +221,13 @@ void transport_init_queue_obj(struct se_queue_obj *qobj)
 }
 EXPORT_SYMBOL(transport_init_queue_obj);
 
-static int transport_subsystem_reqmods(void)
+void transport_subsystem_check_init(void)
 {
        int ret;
 
+       if (sub_api_initialized)
+               return;
+
        ret = request_module("target_core_iblock");
        if (ret != 0)
                pr_err("Unable to load target_core_iblock\n");
@@ -254,24 +244,8 @@ static int transport_subsystem_reqmods(void)
        if (ret != 0)
                pr_err("Unable to load target_core_stgt\n");
 
-       return 0;
-}
-
-int transport_subsystem_check_init(void)
-{
-       int ret;
-
-       if (sub_api_initialized)
-               return 0;
-       /*
-        * Request the loading of known TCM subsystem plugins..
-        */
-       ret = transport_subsystem_reqmods();
-       if (ret < 0)
-               return ret;
-
        sub_api_initialized = 1;
-       return 0;
+       return;
 }
 
 struct se_session *transport_init_session(void)
@@ -286,6 +260,9 @@ struct se_session *transport_init_session(void)
        }
        INIT_LIST_HEAD(&se_sess->sess_list);
        INIT_LIST_HEAD(&se_sess->sess_acl_list);
+       INIT_LIST_HEAD(&se_sess->sess_cmd_list);
+       INIT_LIST_HEAD(&se_sess->sess_wait_list);
+       spin_lock_init(&se_sess->sess_cmd_lock);
 
        return se_sess;
 }
@@ -438,16 +415,15 @@ EXPORT_SYMBOL(transport_deregister_session);
  */
 static void transport_all_task_dev_remove_state(struct se_cmd *cmd)
 {
-       struct se_device *dev;
+       struct se_device *dev = cmd->se_dev;
        struct se_task *task;
        unsigned long flags;
 
-       list_for_each_entry(task, &cmd->t_task_list, t_list) {
-               dev = task->se_dev;
-               if (!dev)
-                       continue;
+       if (!dev)
+               return;
 
-               if (atomic_read(&task->task_active))
+       list_for_each_entry(task, &cmd->t_task_list, t_list) {
+               if (task->task_flags & TF_ACTIVE)
                        continue;
 
                if (!atomic_read(&task->task_state_active))
@@ -489,8 +465,6 @@ static int transport_cmd_check_stop(
                        " == TRUE for ITT: 0x%08x\n", __func__, __LINE__,
                        cmd->se_tfo->get_task_tag(cmd));
 
-               cmd->deferred_t_state = cmd->t_state;
-               cmd->t_state = TRANSPORT_DEFERRED_CMD;
                atomic_set(&cmd->t_transport_active, 0);
                if (transport_off == 2)
                        transport_all_task_dev_remove_state(cmd);
@@ -508,8 +482,6 @@ static int transport_cmd_check_stop(
                        " TRUE for ITT: 0x%08x\n", __func__, __LINE__,
                        cmd->se_tfo->get_task_tag(cmd));
 
-               cmd->deferred_t_state = cmd->t_state;
-               cmd->t_state = TRANSPORT_DEFERRED_CMD;
                if (transport_off == 2)
                        transport_all_task_dev_remove_state(cmd);
 
@@ -537,13 +509,16 @@ static int transport_cmd_check_stop(
                         * Some fabric modules like tcm_loop can release
                         * their internally allocated I/O reference now and
                         * struct se_cmd now.
+                        *
+                        * Fabric modules are expected to return '1' here if the
+                        * se_cmd being passed is released at this point,
+                        * or zero if not being released.
                         */
                        if (cmd->se_tfo->check_stop_free != NULL) {
                                spin_unlock_irqrestore(
                                        &cmd->t_state_lock, flags);
 
-                               cmd->se_tfo->check_stop_free(cmd);
-                               return 1;
+                               return cmd->se_tfo->check_stop_free(cmd);
                        }
                }
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
@@ -594,35 +569,24 @@ check_lun:
 
 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 {
-       transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
-       transport_lun_remove_cmd(cmd);
-
-       if (transport_cmd_check_stop_to_fabric(cmd))
-               return;
-       if (remove)
-               transport_generic_remove(cmd, 0);
-}
-
-void transport_cmd_finish_abort_tmr(struct se_cmd *cmd)
-{
-       transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
+       if (!cmd->se_tmr_req)
+               transport_lun_remove_cmd(cmd);
 
        if (transport_cmd_check_stop_to_fabric(cmd))
                return;
-
-       transport_generic_remove(cmd, 0);
+       if (remove) {
+               transport_remove_cmd_from_queue(cmd);
+               transport_put_cmd(cmd);
+       }
 }
 
-static void transport_add_cmd_to_queue(
-       struct se_cmd *cmd,
-       int t_state)
+static void transport_add_cmd_to_queue(struct se_cmd *cmd, int t_state,
+               bool at_head)
 {
        struct se_device *dev = cmd->se_dev;
        struct se_queue_obj *qobj = &dev->dev_queue_obj;
        unsigned long flags;
 
-       INIT_LIST_HEAD(&cmd->se_queue_node);
-
        if (t_state) {
                spin_lock_irqsave(&cmd->t_state_lock, flags);
                cmd->t_state = t_state;
@@ -631,15 +595,20 @@ static void transport_add_cmd_to_queue(
        }
 
        spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
-       if (cmd->se_cmd_flags & SCF_EMULATE_QUEUE_FULL) {
-               cmd->se_cmd_flags &= ~SCF_EMULATE_QUEUE_FULL;
+
+       /* If the cmd is already on the list, remove it before we add it */
+       if (!list_empty(&cmd->se_queue_node))
+               list_del(&cmd->se_queue_node);
+       else
+               atomic_inc(&qobj->queue_cnt);
+
+       if (at_head)
                list_add(&cmd->se_queue_node, &qobj->qobj_list);
-       else
+       else
                list_add_tail(&cmd->se_queue_node, &qobj->qobj_list);
-       atomic_inc(&cmd->t_transport_queue_active);
+       atomic_set(&cmd->t_transport_queue_active, 1);
        spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
 
-       atomic_inc(&qobj->queue_cnt);
        wake_up_interruptible(&qobj->thread_wq);
 }
 
@@ -656,19 +625,18 @@ transport_get_cmd_from_queue(struct se_queue_obj *qobj)
        }
        cmd = list_first_entry(&qobj->qobj_list, struct se_cmd, se_queue_node);
 
-       atomic_dec(&cmd->t_transport_queue_active);
+       atomic_set(&cmd->t_transport_queue_active, 0);
 
-       list_del(&cmd->se_queue_node);
+       list_del_init(&cmd->se_queue_node);
        atomic_dec(&qobj->queue_cnt);
        spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
 
        return cmd;
 }
 
-static void transport_remove_cmd_from_queue(struct se_cmd *cmd,
-               struct se_queue_obj *qobj)
+static void transport_remove_cmd_from_queue(struct se_cmd *cmd)
 {
-       struct se_cmd *t;
+       struct se_queue_obj *qobj = &cmd->se_dev->dev_queue_obj;
        unsigned long flags;
 
        spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
@@ -676,14 +644,9 @@ static void transport_remove_cmd_from_queue(struct se_cmd *cmd,
                spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
                return;
        }
-
-       list_for_each_entry(t, &qobj->qobj_list, se_queue_node)
-               if (t == cmd) {
-                       atomic_dec(&cmd->t_transport_queue_active);
-                       atomic_dec(&qobj->queue_cnt);
-                       list_del(&cmd->se_queue_node);
-                       break;
-               }
+       atomic_set(&cmd->t_transport_queue_active, 0);
+       atomic_dec(&qobj->queue_cnt);
+       list_del_init(&cmd->se_queue_node);
        spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
 
        if (atomic_read(&cmd->t_transport_queue_active)) {
@@ -707,15 +670,22 @@ void transport_complete_sync_cache(struct se_cmd *cmd, int good)
                task->task_scsi_status = GOOD;
        } else {
                task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
-               task->task_error_status = PYX_TRANSPORT_ILLEGAL_REQUEST;
-               task->task_se_cmd->transport_error_status =
-                                       PYX_TRANSPORT_ILLEGAL_REQUEST;
+               task->task_se_cmd->scsi_sense_reason =
+                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
        }
 
        transport_complete_task(task, good);
 }
 EXPORT_SYMBOL(transport_complete_sync_cache);
 
+static void target_complete_failure_work(struct work_struct *work)
+{
+       struct se_cmd *cmd = container_of(work, struct se_cmd, work);
+
+       transport_generic_request_failure(cmd);
+}
+
 /*     transport_complete_task():
  *
  *     Called from interrupt and non interrupt context depending
@@ -724,8 +694,7 @@ EXPORT_SYMBOL(transport_complete_sync_cache);
 void transport_complete_task(struct se_task *task, int success)
 {
        struct se_cmd *cmd = task->task_se_cmd;
-       struct se_device *dev = task->se_dev;
-       int t_state;
+       struct se_device *dev = cmd->se_dev;
        unsigned long flags;
 #if 0
        pr_debug("task: %p CDB: 0x%02x obj_ptr: %p\n", task,
@@ -735,7 +704,7 @@ void transport_complete_task(struct se_task *task, int success)
                atomic_inc(&dev->depth_left);
 
        spin_lock_irqsave(&cmd->t_state_lock, flags);
-       atomic_set(&task->task_active, 0);
+       task->task_flags &= ~TF_ACTIVE;
 
        /*
         * See if any sense data exists, if so set the TASK_SENSE flag.
@@ -754,39 +723,14 @@ void transport_complete_task(struct se_task *task, int success)
         * See if we are waiting for outstanding struct se_task
         * to complete for an exception condition
         */
-       if (atomic_read(&task->task_stop)) {
-               /*
-                * Decrement cmd->t_se_count if this task had
-                * previously thrown its timeout exception handler.
-                */
-               if (atomic_read(&task->task_timeout)) {
-                       atomic_dec(&cmd->t_se_count);
-                       atomic_set(&task->task_timeout, 0);
-               }
+       if (task->task_flags & TF_REQUEST_STOP) {
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
                complete(&task->task_stop_comp);
                return;
        }
-       /*
-        * If the task's timeout handler has fired, use the t_task_cdbs_timeout
-        * left counter to determine when the struct se_cmd is ready to be queued to
-        * the processing thread.
-        */
-       if (atomic_read(&task->task_timeout)) {
-               if (!atomic_dec_and_test(
-                               &cmd->t_task_cdbs_timeout_left)) {
-                       spin_unlock_irqrestore(&cmd->t_state_lock,
-                               flags);
-                       return;
-               }
-               t_state = TRANSPORT_COMPLETE_TIMEOUT;
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-               transport_add_cmd_to_queue(cmd, t_state);
-               return;
-       }
-       atomic_dec(&cmd->t_task_cdbs_timeout_left);
+       if (!success)
+               cmd->t_tasks_failed = 1;
 
        /*
         * Decrement the outstanding t_task_cdbs_left count.  The last
@@ -794,28 +738,29 @@ void transport_complete_task(struct se_task *task, int success)
         * device queue depending upon int success.
         */
        if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
-               if (!success)
-                       cmd->t_tasks_failed = 1;
-
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
                return;
        }
 
-       if (!success || cmd->t_tasks_failed) {
-               t_state = TRANSPORT_COMPLETE_FAILURE;
+       if (cmd->t_tasks_failed) {
                if (!task->task_error_status) {
                        task->task_error_status =
-                               PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
-                       cmd->transport_error_status =
-                               PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+                       cmd->scsi_sense_reason =
+                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
                }
+
+               INIT_WORK(&cmd->work, target_complete_failure_work);
        } else {
                atomic_set(&cmd->t_transport_complete, 1);
-               t_state = TRANSPORT_COMPLETE_OK;
+               INIT_WORK(&cmd->work, target_complete_ok_work);
        }
+
+       cmd->t_state = TRANSPORT_COMPLETE;
+       atomic_set(&cmd->t_transport_active, 1);
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-       transport_add_cmd_to_queue(cmd, t_state);
+       queue_work(target_completion_wq, &cmd->work);
 }
 EXPORT_SYMBOL(transport_complete_task);
 
@@ -902,14 +847,12 @@ static void __transport_add_task_to_execute_queue(
 
 static void transport_add_tasks_to_state_queue(struct se_cmd *cmd)
 {
-       struct se_device *dev;
+       struct se_device *dev = cmd->se_dev;
        struct se_task *task;
        unsigned long flags;
 
        spin_lock_irqsave(&cmd->t_state_lock, flags);
        list_for_each_entry(task, &cmd->t_task_list, t_list) {
-               dev = task->se_dev;
-
                if (atomic_read(&task->task_state_active))
                        continue;
 
@@ -934,73 +877,67 @@ static void transport_add_tasks_from_cmd(struct se_cmd *cmd)
 
        spin_lock_irqsave(&dev->execute_task_lock, flags);
        list_for_each_entry(task, &cmd->t_task_list, t_list) {
-               if (atomic_read(&task->task_execute_queue))
+               if (!list_empty(&task->t_execute_list))
                        continue;
                /*
                 * __transport_add_task_to_execute_queue() handles the
                 * SAM Task Attribute emulation if enabled
                 */
                __transport_add_task_to_execute_queue(task, task_prev, dev);
-               atomic_set(&task->task_execute_queue, 1);
                task_prev = task;
        }
        spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 }
 
-/*     transport_remove_task_from_execute_queue():
- *
- *
- */
+void __transport_remove_task_from_execute_queue(struct se_task *task,
+               struct se_device *dev)
+{
+       list_del_init(&task->t_execute_list);
+       atomic_dec(&dev->execute_tasks);
+}
+
 void transport_remove_task_from_execute_queue(
        struct se_task *task,
        struct se_device *dev)
 {
        unsigned long flags;
 
-       if (atomic_read(&task->task_execute_queue) == 0) {
-               dump_stack();
+       if (WARN_ON(list_empty(&task->t_execute_list)))
                return;
-       }
 
        spin_lock_irqsave(&dev->execute_task_lock, flags);
-       list_del(&task->t_execute_list);
-       atomic_set(&task->task_execute_queue, 0);
-       atomic_dec(&dev->execute_tasks);
+       __transport_remove_task_from_execute_queue(task, dev);
        spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 }
 
 /*
- * Handle QUEUE_FULL / -EAGAIN status
+ * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
  */
 
 static void target_qf_do_work(struct work_struct *work)
 {
        struct se_device *dev = container_of(work, struct se_device,
                                        qf_work_queue);
+       LIST_HEAD(qf_cmd_list);
        struct se_cmd *cmd, *cmd_tmp;
 
        spin_lock_irq(&dev->qf_cmd_lock);
-       list_for_each_entry_safe(cmd, cmd_tmp, &dev->qf_cmd_list, se_qf_node) {
+       list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
+       spin_unlock_irq(&dev->qf_cmd_lock);
 
+       list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
                list_del(&cmd->se_qf_node);
                atomic_dec(&dev->dev_qf_count);
                smp_mb__after_atomic_dec();
-               spin_unlock_irq(&dev->qf_cmd_lock);
 
                pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
                        " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
-                       (cmd->t_state == TRANSPORT_COMPLETE_OK) ? "COMPLETE_OK" :
+                       (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
                        (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
                        : "UNKNOWN");
-               /*
-                * The SCF_EMULATE_QUEUE_FULL flag will be cleared once se_cmd
-                * has been added to head of queue
-                */
-               transport_add_cmd_to_queue(cmd, cmd->t_state);
 
-               spin_lock_irq(&dev->qf_cmd_lock);
+               transport_add_cmd_to_queue(cmd, cmd->t_state, true);
        }
-       spin_unlock_irq(&dev->qf_cmd_lock);
 }
 
 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
@@ -1054,41 +991,6 @@ void transport_dump_dev_state(
        *bl += sprintf(b + *bl, "        ");
 }
 
-/*     transport_release_all_cmds():
- *
- *
- */
-static void transport_release_all_cmds(struct se_device *dev)
-{
-       struct se_cmd *cmd, *tcmd;
-       int bug_out = 0, t_state;
-       unsigned long flags;
-
-       spin_lock_irqsave(&dev->dev_queue_obj.cmd_queue_lock, flags);
-       list_for_each_entry_safe(cmd, tcmd, &dev->dev_queue_obj.qobj_list,
-                               se_queue_node) {
-               t_state = cmd->t_state;
-               list_del(&cmd->se_queue_node);
-               spin_unlock_irqrestore(&dev->dev_queue_obj.cmd_queue_lock,
-                               flags);
-
-               pr_err("Releasing ITT: 0x%08x, i_state: %u,"
-                       " t_state: %u directly\n",
-                       cmd->se_tfo->get_task_tag(cmd),
-                       cmd->se_tfo->get_cmd_state(cmd), t_state);
-
-               transport_release_fe_cmd(cmd);
-               bug_out = 1;
-
-               spin_lock_irqsave(&dev->dev_queue_obj.cmd_queue_lock, flags);
-       }
-       spin_unlock_irqrestore(&dev->dev_queue_obj.cmd_queue_lock, flags);
-#if 0
-       if (bug_out)
-               BUG();
-#endif
-}
-
 void transport_dump_vpd_proto_id(
        struct t10_vpd *vpd,
        unsigned char *p_buf,
@@ -1424,23 +1326,17 @@ struct se_device *transport_add_device_to_core_hba(
        dev->se_hba             = hba;
        dev->se_sub_dev         = se_dev;
        dev->transport          = transport;
-       atomic_set(&dev->active_cmds, 0);
        INIT_LIST_HEAD(&dev->dev_list);
        INIT_LIST_HEAD(&dev->dev_sep_list);
        INIT_LIST_HEAD(&dev->dev_tmr_list);
        INIT_LIST_HEAD(&dev->execute_task_list);
        INIT_LIST_HEAD(&dev->delayed_cmd_list);
-       INIT_LIST_HEAD(&dev->ordered_cmd_list);
        INIT_LIST_HEAD(&dev->state_task_list);
        INIT_LIST_HEAD(&dev->qf_cmd_list);
        spin_lock_init(&dev->execute_task_lock);
        spin_lock_init(&dev->delayed_cmd_lock);
-       spin_lock_init(&dev->ordered_cmd_lock);
-       spin_lock_init(&dev->state_task_lock);
-       spin_lock_init(&dev->dev_alua_lock);
        spin_lock_init(&dev->dev_reservation_lock);
        spin_lock_init(&dev->dev_status_lock);
-       spin_lock_init(&dev->dev_status_thr_lock);
        spin_lock_init(&dev->se_port_lock);
        spin_lock_init(&dev->se_tmr_lock);
        spin_lock_init(&dev->qf_cmd_lock);
@@ -1574,7 +1470,6 @@ transport_generic_get_task(struct se_cmd *cmd,
        INIT_LIST_HEAD(&task->t_state_list);
        init_completion(&task->task_stop_comp);
        task->task_se_cmd = cmd;
-       task->se_dev = dev;
        task->task_data_direction = data_direction;
 
        return task;
@@ -1597,13 +1492,14 @@ void transport_init_se_cmd(
 {
        INIT_LIST_HEAD(&cmd->se_lun_node);
        INIT_LIST_HEAD(&cmd->se_delayed_node);
-       INIT_LIST_HEAD(&cmd->se_ordered_node);
        INIT_LIST_HEAD(&cmd->se_qf_node);
-
+       INIT_LIST_HEAD(&cmd->se_queue_node);
+       INIT_LIST_HEAD(&cmd->se_cmd_list);
        INIT_LIST_HEAD(&cmd->t_task_list);
        init_completion(&cmd->transport_lun_fe_stop_comp);
        init_completion(&cmd->transport_lun_stop_comp);
        init_completion(&cmd->t_transport_stop_comp);
+       init_completion(&cmd->cmd_wait_comp);
        spin_lock_init(&cmd->t_state_lock);
        atomic_set(&cmd->transport_dev_active, 1);
 
@@ -1642,21 +1538,6 @@ static int transport_check_alloc_task_attr(struct se_cmd *cmd)
        return 0;
 }
 
-void transport_free_se_cmd(
-       struct se_cmd *se_cmd)
-{
-       if (se_cmd->se_tmr_req)
-               core_tmr_release_req(se_cmd->se_tmr_req);
-       /*
-        * Check and free any extended CDB buffer that was allocated
-        */
-       if (se_cmd->t_task_cdb != se_cmd->__t_task_cdb)
-               kfree(se_cmd->t_task_cdb);
-}
-EXPORT_SYMBOL(transport_free_se_cmd);
-
-static void transport_generic_wait_for_tasks(struct se_cmd *, int, int);
-
 /*     transport_generic_allocate_tasks():
  *
  *     Called from fabric RX Thread.
@@ -1668,12 +1549,6 @@ int transport_generic_allocate_tasks(
        int ret;
 
        transport_generic_prepare_cdb(cdb);
-
-       /*
-        * This is needed for early exceptions.
-        */
-       cmd->transport_wait_for_tasks = &transport_generic_wait_for_tasks;
-
        /*
         * Ensure that the received CDB is less than the max (252 + 8) bytes
         * for VARIABLE_LENGTH_CMD
@@ -1682,6 +1557,8 @@ int transport_generic_allocate_tasks(
                pr_err("Received SCSI CDB with command_size: %d that"
                        " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
                        scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
+               cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
+               cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
                return -EINVAL;
        }
        /*
@@ -1697,6 +1574,9 @@ int transport_generic_allocate_tasks(
                                " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
                                scsi_command_size(cdb),
                                (unsigned long)sizeof(cmd->__t_task_cdb));
+                       cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
+                       cmd->scsi_sense_reason =
+                                       TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
                        return -ENOMEM;
                }
        } else
@@ -1730,26 +1610,6 @@ int transport_generic_allocate_tasks(
 }
 EXPORT_SYMBOL(transport_generic_allocate_tasks);
 
-/*
- * Used by fabric module frontends not defining a TFO->new_cmd_map()
- * to queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD statis
- */
-int transport_generic_handle_cdb(
-       struct se_cmd *cmd)
-{
-       if (!cmd->se_lun) {
-               dump_stack();
-               pr_err("cmd->se_lun is NULL\n");
-               return -EINVAL;
-       }
-
-       transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD);
-       return 0;
-}
-EXPORT_SYMBOL(transport_generic_handle_cdb);
-
-static void transport_generic_request_failure(struct se_cmd *,
-                       struct se_device *, int, int);
 /*
  * Used by fabric module frontends to queue tasks directly.
  * Many only be used from process context only
@@ -1774,7 +1634,7 @@ int transport_handle_cdb_direct(
         * Set TRANSPORT_NEW_CMD state and cmd->t_transport_active=1 following
         * transport_generic_handle_cdb*() -> transport_add_cmd_to_queue()
         * in existing usage to ensure that outstanding descriptors are handled
-        * correctly during shutdown via transport_generic_wait_for_tasks()
+        * correctly during shutdown via transport_wait_for_tasks()
         *
         * Also, we don't take cmd->t_state_lock here as we only expect
         * this to be called for initial descriptor submission.
@@ -1787,13 +1647,9 @@ int transport_handle_cdb_direct(
         * and call transport_generic_request_failure() if necessary..
         */
        ret = transport_generic_new_cmd(cmd);
-       if (ret == -EAGAIN)
-               return 0;
-       else if (ret < 0) {
-               cmd->transport_error_status = ret;
-               transport_generic_request_failure(cmd, NULL, 0,
-                               (cmd->data_direction != DMA_TO_DEVICE));
-       }
+       if (ret < 0)
+               transport_generic_request_failure(cmd);
+
        return 0;
 }
 EXPORT_SYMBOL(transport_handle_cdb_direct);
@@ -1812,7 +1668,7 @@ int transport_generic_handle_cdb_map(
                return -EINVAL;
        }
 
-       transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP);
+       transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP, false);
        return 0;
 }
 EXPORT_SYMBOL(transport_generic_handle_cdb_map);
@@ -1842,7 +1698,7 @@ int transport_generic_handle_data(
        if (transport_check_aborted_status(cmd, 1) != 0)
                return 0;
 
-       transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE);
+       transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE, false);
        return 0;
 }
 EXPORT_SYMBOL(transport_generic_handle_data);
@@ -1854,22 +1710,36 @@ EXPORT_SYMBOL(transport_generic_handle_data);
 int transport_generic_handle_tmr(
        struct se_cmd *cmd)
 {
-       /*
-        * This is needed for early exceptions.
-        */
-       cmd->transport_wait_for_tasks = &transport_generic_wait_for_tasks;
-
-       transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR);
+       transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR, false);
        return 0;
 }
 EXPORT_SYMBOL(transport_generic_handle_tmr);
 
-void transport_generic_free_cmd_intr(
-       struct se_cmd *cmd)
+/*
+ * If the task is active, request it to be stopped and sleep until it
+ * has completed.
+ */
+bool target_stop_task(struct se_task *task, unsigned long *flags)
 {
-       transport_add_cmd_to_queue(cmd, TRANSPORT_FREE_CMD_INTR);
+       struct se_cmd *cmd = task->task_se_cmd;
+       bool was_active = false;
+
+       if (task->task_flags & TF_ACTIVE) {
+               task->task_flags |= TF_REQUEST_STOP;
+               spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
+
+               pr_debug("Task %p waiting to complete\n", task);
+               wait_for_completion(&task->task_stop_comp);
+               pr_debug("Task %p stopped successfully\n", task);
+
+               spin_lock_irqsave(&cmd->t_state_lock, *flags);
+               atomic_dec(&cmd->t_task_cdbs_left);
+               task->task_flags &= ~(TF_ACTIVE | TF_REQUEST_STOP);
+               was_active = true;
+       }
+
+       return was_active;
 }
-EXPORT_SYMBOL(transport_generic_free_cmd_intr);
 
 static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
 {
@@ -1886,51 +1756,26 @@ static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
        spin_lock_irqsave(&cmd->t_state_lock, flags);
        list_for_each_entry_safe(task, task_tmp,
                                &cmd->t_task_list, t_list) {
-               pr_debug("task_no[%d] - Processing task %p\n",
-                               task->task_no, task);
+               pr_debug("Processing task %p\n", task);
                /*
                 * If the struct se_task has not been sent and is not active,
                 * remove the struct se_task from the execution queue.
                 */
-               if (!atomic_read(&task->task_sent) &&
-                   !atomic_read(&task->task_active)) {
+               if (!(task->task_flags & (TF_ACTIVE | TF_SENT))) {
                        spin_unlock_irqrestore(&cmd->t_state_lock,
                                        flags);
                        transport_remove_task_from_execute_queue(task,
-                                       task->se_dev);
+                                       cmd->se_dev);
 
-                       pr_debug("task_no[%d] - Removed from execute queue\n",
-                               task->task_no);
+                       pr_debug("Task %p removed from execute queue\n", task);
                        spin_lock_irqsave(&cmd->t_state_lock, flags);
                        continue;
                }
 
-               /*
-                * If the struct se_task is active, sleep until it is returned
-                * from the plugin.
-                */
-               if (atomic_read(&task->task_active)) {
-                       atomic_set(&task->task_stop, 1);
-                       spin_unlock_irqrestore(&cmd->t_state_lock,
-                                       flags);
-
-                       pr_debug("task_no[%d] - Waiting to complete\n",
-                               task->task_no);
-                       wait_for_completion(&task->task_stop_comp);
-                       pr_debug("task_no[%d] - Stopped successfully\n",
-                               task->task_no);
-
-                       spin_lock_irqsave(&cmd->t_state_lock, flags);
-                       atomic_dec(&cmd->t_task_cdbs_left);
-
-                       atomic_set(&task->task_active, 0);
-                       atomic_set(&task->task_stop, 0);
-               } else {
-                       pr_debug("task_no[%d] - Did nothing\n", task->task_no);
+               if (!target_stop_task(task, &flags)) {
+                       pr_debug("Task %p - did nothing\n", task);
                        ret++;
                }
-
-               __transport_stop_task_timer(task, &flags);
        }
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
@@ -1940,22 +1785,16 @@ static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
 /*
  * Handle SAM-esque emulation for generic transport request failures.
  */
-static void transport_generic_request_failure(
-       struct se_cmd *cmd,
-       struct se_device *dev,
-       int complete,
-       int sc)
+static void transport_generic_request_failure(struct se_cmd *cmd)
 {
        int ret = 0;
 
        pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
                " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
                cmd->t_task_cdb[0]);
-       pr_debug("-----[ i_state: %d t_state/def_t_state:"
-               " %d/%d transport_error_status: %d\n",
+       pr_debug("-----[ i_state: %d t_state: %d scsi_sense_reason: %d\n",
                cmd->se_tfo->get_cmd_state(cmd),
-               cmd->t_state, cmd->deferred_t_state,
-               cmd->transport_error_status);
+               cmd->t_state, cmd->scsi_sense_reason);
        pr_debug("-----[ t_tasks: %d t_task_cdbs_left: %d"
                " t_task_cdbs_sent: %d t_task_cdbs_ex_left: %d --"
                " t_transport_active: %d t_transport_stop: %d"
@@ -1967,57 +1806,25 @@ static void transport_generic_request_failure(
                atomic_read(&cmd->t_transport_stop),
                atomic_read(&cmd->t_transport_sent));
 
-       transport_stop_all_task_timers(cmd);
-
-       if (dev)
-               atomic_inc(&dev->depth_left);
        /*
         * For SAM Task Attribute emulation for failed struct se_cmd
         */
        if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
                transport_complete_task_attr(cmd);
 
-       if (complete) {
-               transport_direct_request_timeout(cmd);
-               cmd->transport_error_status = PYX_TRANSPORT_LU_COMM_FAILURE;
-       }
-
-       switch (cmd->transport_error_status) {
-       case PYX_TRANSPORT_UNKNOWN_SAM_OPCODE:
-               cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
-               break;
-       case PYX_TRANSPORT_REQ_TOO_MANY_SECTORS:
-               cmd->scsi_sense_reason = TCM_SECTOR_COUNT_TOO_MANY;
-               break;
-       case PYX_TRANSPORT_INVALID_CDB_FIELD:
-               cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
-               break;
-       case PYX_TRANSPORT_INVALID_PARAMETER_LIST:
-               cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
-               break;
-       case PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES:
-               if (!sc)
-                       transport_new_cmd_failure(cmd);
-               /*
-                * Currently for PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES,
-                * we force this session to fall back to session
-                * recovery.
-                */
-               cmd->se_tfo->fall_back_to_erl0(cmd->se_sess);
-               cmd->se_tfo->stop_session(cmd->se_sess, 0, 0);
-
-               goto check_stop;
-       case PYX_TRANSPORT_LU_COMM_FAILURE:
-       case PYX_TRANSPORT_ILLEGAL_REQUEST:
-               cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-               break;
-       case PYX_TRANSPORT_UNKNOWN_MODE_PAGE:
-               cmd->scsi_sense_reason = TCM_UNKNOWN_MODE_PAGE;
-               break;
-       case PYX_TRANSPORT_WRITE_PROTECTED:
-               cmd->scsi_sense_reason = TCM_WRITE_PROTECTED;
+       switch (cmd->scsi_sense_reason) {
+       case TCM_NON_EXISTENT_LUN:
+       case TCM_UNSUPPORTED_SCSI_OPCODE:
+       case TCM_INVALID_CDB_FIELD:
+       case TCM_INVALID_PARAMETER_LIST:
+       case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
+       case TCM_UNKNOWN_MODE_PAGE:
+       case TCM_WRITE_PROTECTED:
+       case TCM_CHECK_CONDITION_ABORT_CMD:
+       case TCM_CHECK_CONDITION_UNIT_ATTENTION:
+       case TCM_CHECK_CONDITION_NOT_READY:
                break;
-       case PYX_TRANSPORT_RESERVATION_CONFLICT:
+       case TCM_RESERVATION_CONFLICT:
                /*
                 * No SENSE Data payload for this case, set SCSI Status
                 * and queue the response to $FABRIC_MOD.
@@ -2039,18 +1846,12 @@ static void transport_generic_request_failure(
                                ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
 
                ret = cmd->se_tfo->queue_status(cmd);
-               if (ret == -EAGAIN)
+               if (ret == -EAGAIN || ret == -ENOMEM)
                        goto queue_full;
                goto check_stop;
-       case PYX_TRANSPORT_USE_SENSE_REASON:
-               /*
-                * struct se_cmd->scsi_sense_reason already set
-                */
-               break;
        default:
                pr_err("Unknown transport error for CDB 0x%02x: %d\n",
-                       cmd->t_task_cdb[0],
-                       cmd->transport_error_status);
+                       cmd->t_task_cdb[0], cmd->scsi_sense_reason);
                cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
                break;
        }
@@ -2061,14 +1862,10 @@ static void transport_generic_request_failure(
         * transport_send_check_condition_and_sense() after handling
         * possible unsoliticied write data payloads.
         */
-       if (!sc && !cmd->se_tfo->new_cmd_map)
-               transport_new_cmd_failure(cmd);
-       else {
-               ret = transport_send_check_condition_and_sense(cmd,
-                               cmd->scsi_sense_reason, 0);
-               if (ret == -EAGAIN)
-                       goto queue_full;
-       }
+       ret = transport_send_check_condition_and_sense(cmd,
+                       cmd->scsi_sense_reason, 0);
+       if (ret == -EAGAIN || ret == -ENOMEM)
+               goto queue_full;
 
 check_stop:
        transport_lun_remove_cmd(cmd);
@@ -2077,46 +1874,8 @@ check_stop:
        return;
 
 queue_full:
-       cmd->t_state = TRANSPORT_COMPLETE_OK;
-       transport_handle_queue_full(cmd, cmd->se_dev, transport_complete_qf);
-}
-
-static void transport_direct_request_timeout(struct se_cmd *cmd)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&cmd->t_state_lock, flags);
-       if (!atomic_read(&cmd->t_transport_timeout)) {
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               return;
-       }
-       if (atomic_read(&cmd->t_task_cdbs_timeout_left)) {
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               return;
-       }
-
-       atomic_sub(atomic_read(&cmd->t_transport_timeout),
-                  &cmd->t_se_count);
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-}
-
-static void transport_generic_request_timeout(struct se_cmd *cmd)
-{
-       unsigned long flags;
-
-       /*
-        * Reset cmd->t_se_count to allow transport_generic_remove()
-        * to allow last call to free memory resources.
-        */
-       spin_lock_irqsave(&cmd->t_state_lock, flags);
-       if (atomic_read(&cmd->t_transport_timeout) > 1) {
-               int tmp = (atomic_read(&cmd->t_transport_timeout) - 1);
-
-               atomic_sub(tmp, &cmd->t_se_count);
-       }
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
-       transport_generic_remove(cmd, 0);
+       cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
+       transport_handle_queue_full(cmd, cmd->se_dev);
 }
 
 static inline u32 transport_lba_21(unsigned char *cdb)
@@ -2161,138 +1920,17 @@ static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd)
        spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
 }
 
-/*
- * Called from interrupt context.
- */
-static void transport_task_timeout_handler(unsigned long data)
+static inline int transport_tcq_window_closed(struct se_device *dev)
 {
-       struct se_task *task = (struct se_task *)data;
-       struct se_cmd *cmd = task->task_se_cmd;
-       unsigned long flags;
+       if (dev->dev_tcq_window_closed++ <
+                       PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) {
+               msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT);
+       } else
+               msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG);
 
-       pr_debug("transport task timeout fired! task: %p cmd: %p\n", task, cmd);
-
-       spin_lock_irqsave(&cmd->t_state_lock, flags);
-       if (task->task_flags & TF_STOP) {
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               return;
-       }
-       task->task_flags &= ~TF_RUNNING;
-
-       /*
-        * Determine if transport_complete_task() has already been called.
-        */
-       if (!atomic_read(&task->task_active)) {
-               pr_debug("transport task: %p cmd: %p timeout task_active"
-                               " == 0\n", task, cmd);
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               return;
-       }
-
-       atomic_inc(&cmd->t_se_count);
-       atomic_inc(&cmd->t_transport_timeout);
-       cmd->t_tasks_failed = 1;
-
-       atomic_set(&task->task_timeout, 1);
-       task->task_error_status = PYX_TRANSPORT_TASK_TIMEOUT;
-       task->task_scsi_status = 1;
-
-       if (atomic_read(&task->task_stop)) {
-               pr_debug("transport task: %p cmd: %p timeout task_stop"
-                               " == 1\n", task, cmd);
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               complete(&task->task_stop_comp);
-               return;
-       }
-
-       if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
-               pr_debug("transport task: %p cmd: %p timeout non zero"
-                               " t_task_cdbs_left\n", task, cmd);
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               return;
-       }
-       pr_debug("transport task: %p cmd: %p timeout ZERO t_task_cdbs_left\n",
-                       task, cmd);
-
-       cmd->t_state = TRANSPORT_COMPLETE_FAILURE;
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
-       transport_add_cmd_to_queue(cmd, TRANSPORT_COMPLETE_FAILURE);
-}
-
-/*
- * Called with cmd->t_state_lock held.
- */
-static void transport_start_task_timer(struct se_task *task)
-{
-       struct se_device *dev = task->se_dev;
-       int timeout;
-
-       if (task->task_flags & TF_RUNNING)
-               return;
-       /*
-        * If the task_timeout is disabled, exit now.
-        */
-       timeout = dev->se_sub_dev->se_dev_attrib.task_timeout;
-       if (!timeout)
-               return;
-
-       init_timer(&task->task_timer);
-       task->task_timer.expires = (get_jiffies_64() + timeout * HZ);
-       task->task_timer.data = (unsigned long) task;
-       task->task_timer.function = transport_task_timeout_handler;
-
-       task->task_flags |= TF_RUNNING;
-       add_timer(&task->task_timer);
-#if 0
-       pr_debug("Starting task timer for cmd: %p task: %p seconds:"
-               " %d\n", task->task_se_cmd, task, timeout);
-#endif
-}
-
-/*
- * Called with spin_lock_irq(&cmd->t_state_lock) held.
- */
-void __transport_stop_task_timer(struct se_task *task, unsigned long *flags)
-{
-       struct se_cmd *cmd = task->task_se_cmd;
-
-       if (!task->task_flags & TF_RUNNING)
-               return;
-
-       task->task_flags |= TF_STOP;
-       spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
-
-       del_timer_sync(&task->task_timer);
-
-       spin_lock_irqsave(&cmd->t_state_lock, *flags);
-       task->task_flags &= ~TF_RUNNING;
-       task->task_flags &= ~TF_STOP;
-}
-
-static void transport_stop_all_task_timers(struct se_cmd *cmd)
-{
-       struct se_task *task = NULL, *task_tmp;
-       unsigned long flags;
-
-       spin_lock_irqsave(&cmd->t_state_lock, flags);
-       list_for_each_entry_safe(task, task_tmp,
-                               &cmd->t_task_list, t_list)
-               __transport_stop_task_timer(task, &flags);
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-}
-
-static inline int transport_tcq_window_closed(struct se_device *dev)
-{
-       if (dev->dev_tcq_window_closed++ <
-                       PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) {
-               msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT);
-       } else
-               msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG);
-
-       wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
-       return 0;
-}
+       wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
+       return 0;
+}
 
 /*
  * Called from Fabric Module context from transport_execute_tasks()
@@ -2310,19 +1948,12 @@ static inline int transport_execute_task_attr(struct se_cmd *cmd)
         * to allow the passed struct se_cmd list of tasks to the front of the list.
         */
         if (cmd->sam_task_attr == MSG_HEAD_TAG) {
-               atomic_inc(&cmd->se_dev->dev_hoq_count);
-               smp_mb__after_atomic_inc();
                pr_debug("Added HEAD_OF_QUEUE for CDB:"
                        " 0x%02x, se_ordered_id: %u\n",
                        cmd->t_task_cdb[0],
                        cmd->se_ordered_id);
                return 1;
        } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
-               spin_lock(&cmd->se_dev->ordered_cmd_lock);
-               list_add_tail(&cmd->se_ordered_node,
-                               &cmd->se_dev->ordered_cmd_list);
-               spin_unlock(&cmd->se_dev->ordered_cmd_lock);
-
                atomic_inc(&cmd->se_dev->dev_ordered_sync);
                smp_mb__after_atomic_inc();
 
@@ -2384,9 +2015,9 @@ static int transport_execute_tasks(struct se_cmd *cmd)
 {
        int add_tasks;
 
-       if (se_dev_check_online(cmd->se_orig_obj_ptr) != 0) {
-               cmd->transport_error_status = PYX_TRANSPORT_LU_COMM_FAILURE;
-               transport_generic_request_failure(cmd, NULL, 0, 1);
+       if (se_dev_check_online(cmd->se_dev) != 0) {
+               cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+               transport_generic_request_failure(cmd);
                return 0;
        }
 
@@ -2449,9 +2080,7 @@ check_depth:
        }
        task = list_first_entry(&dev->execute_task_list,
                                struct se_task, t_execute_list);
-       list_del(&task->t_execute_list);
-       atomic_set(&task->task_execute_queue, 0);
-       atomic_dec(&dev->execute_tasks);
+       __transport_remove_task_from_execute_queue(task, dev);
        spin_unlock_irq(&dev->execute_task_lock);
 
        atomic_dec(&dev->depth_left);
@@ -2459,66 +2088,27 @@ check_depth:
        cmd = task->task_se_cmd;
 
        spin_lock_irqsave(&cmd->t_state_lock, flags);
-       atomic_set(&task->task_active, 1);
-       atomic_set(&task->task_sent, 1);
+       task->task_flags |= (TF_ACTIVE | TF_SENT);
        atomic_inc(&cmd->t_task_cdbs_sent);
 
        if (atomic_read(&cmd->t_task_cdbs_sent) ==
            cmd->t_task_list_num)
-               atomic_set(&cmd->transport_sent, 1);
+               atomic_set(&cmd->t_transport_sent, 1);
 
-       transport_start_task_timer(task);
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-       /*
-        * The struct se_cmd->transport_emulate_cdb() function pointer is used
-        * to grab REPORT_LUNS and other CDBs we want to handle before they hit the
-        * struct se_subsystem_api->do_task() caller below.
-        */
-       if (cmd->transport_emulate_cdb) {
-               error = cmd->transport_emulate_cdb(cmd);
-               if (error != 0) {
-                       cmd->transport_error_status = error;
-                       atomic_set(&task->task_active, 0);
-                       atomic_set(&cmd->transport_sent, 0);
-                       transport_stop_tasks_for_cmd(cmd);
-                       transport_generic_request_failure(cmd, dev, 0, 1);
-                       goto check_depth;
-               }
-               /*
-                * Handle the successful completion for transport_emulate_cdb()
-                * for synchronous operation, following SCF_EMULATE_CDB_ASYNC
-                * Otherwise the caller is expected to complete the task with
-                * proper status.
-                */
-               if (!(cmd->se_cmd_flags & SCF_EMULATE_CDB_ASYNC)) {
-                       cmd->scsi_status = SAM_STAT_GOOD;
-                       task->task_scsi_status = GOOD;
-                       transport_complete_task(task, 1);
-               }
-       } else {
-               /*
-                * Currently for all virtual TCM plugins including IBLOCK, FILEIO and
-                * RAMDISK we use the internal transport_emulate_control_cdb() logic
-                * with struct se_subsystem_api callers for the primary SPC-3 TYPE_DISK
-                * LUN emulation code.
-                *
-                * For TCM/pSCSI and all other SCF_SCSI_DATA_SG_IO_CDB I/O tasks we
-                * call ->do_task() directly and let the underlying TCM subsystem plugin
-                * code handle the CDB emulation.
-                */
-               if ((dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) &&
-                   (!(task->task_se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
-                       error = transport_emulate_control_cdb(task);
-               else
-                       error = dev->transport->do_task(task);
-
-               if (error != 0) {
-                       cmd->transport_error_status = error;
-                       atomic_set(&task->task_active, 0);
-                       atomic_set(&cmd->transport_sent, 0);
-                       transport_stop_tasks_for_cmd(cmd);
-                       transport_generic_request_failure(cmd, dev, 0, 1);
-               }
+
+       if (cmd->execute_task)
+               error = cmd->execute_task(task);
+       else
+               error = dev->transport->do_task(task);
+       if (error != 0) {
+               spin_lock_irqsave(&cmd->t_state_lock, flags);
+               task->task_flags &= ~TF_ACTIVE;
+               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+               atomic_set(&cmd->t_transport_sent, 0);
+               transport_stop_tasks_for_cmd(cmd);
+               atomic_inc(&dev->depth_left);
+               transport_generic_request_failure(cmd);
        }
 
        goto check_depth;
@@ -2526,21 +2116,6 @@ check_depth:
        return 0;
 }
 
-void transport_new_cmd_failure(struct se_cmd *se_cmd)
-{
-       unsigned long flags;
-       /*
-        * Any unsolicited data will get dumped for failed command inside of
-        * the fabric plugin
-        */
-       spin_lock_irqsave(&se_cmd->t_state_lock, flags);
-       se_cmd->se_cmd_flags |= SCF_SE_CMD_FAILED;
-       se_cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
-       spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
-}
-
-static void transport_nop_wait_for_tasks(struct se_cmd *, int, int);
-
 static inline u32 transport_get_sectors_6(
        unsigned char *cdb,
        struct se_cmd *cmd,
@@ -2563,10 +2138,15 @@ static inline u32 transport_get_sectors_6(
 
        /*
         * Everything else assume TYPE_DISK Sector CDB location.
-        * Use 8-bit sector value.
+        * Use 8-bit sector value.  SBC-3 says:
+        *
+        *   A TRANSFER LENGTH field set to zero specifies that 256
+        *   logical blocks shall be written.  Any other value
+        *   specifies the number of logical blocks that shall be
+        *   written.
         */
 type_disk:
-       return (u32)cdb[4];
+       return cdb[4] ? : 256;
 }
 
 static inline u32 transport_get_sectors_10(
@@ -2753,13 +2333,16 @@ out:
 static int transport_get_sense_data(struct se_cmd *cmd)
 {
        unsigned char *buffer = cmd->sense_buffer, *sense_buffer = NULL;
-       struct se_device *dev;
+       struct se_device *dev = cmd->se_dev;
        struct se_task *task = NULL, *task_tmp;
        unsigned long flags;
        u32 offset = 0;
 
        WARN_ON(!cmd->se_lun);
 
+       if (!dev)
+               return 0;
+
        spin_lock_irqsave(&cmd->t_state_lock, flags);
        if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
@@ -2768,14 +2351,9 @@ static int transport_get_sense_data(struct se_cmd *cmd)
 
        list_for_each_entry_safe(task, task_tmp,
                                &cmd->t_task_list, t_list) {
-
                if (!task->task_sense)
                        continue;
 
-               dev = task->se_dev;
-               if (!dev)
-                       continue;
-
                if (!dev->transport->get_sense_buffer) {
                        pr_err("dev->transport->get_sense_buffer"
                                        " is NULL\n");
@@ -2784,9 +2362,9 @@ static int transport_get_sense_data(struct se_cmd *cmd)
 
                sense_buffer = dev->transport->get_sense_buffer(task);
                if (!sense_buffer) {
-                       pr_err("ITT[0x%08x]_TASK[%d]: Unable to locate"
+                       pr_err("ITT[0x%08x]_TASK[%p]: Unable to locate"
                                " sense buffer for task with sense\n",
-                               cmd->se_tfo->get_task_tag(cmd), task->task_no);
+                               cmd->se_tfo->get_task_tag(cmd), task);
                        continue;
                }
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
@@ -2812,28 +2390,6 @@ static int transport_get_sense_data(struct se_cmd *cmd)
        return -1;
 }
 
-static int
-transport_handle_reservation_conflict(struct se_cmd *cmd)
-{
-       cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
-       cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
-       cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
-       cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
-       /*
-        * For UA Interlock Code 11b, a RESERVATION CONFLICT will
-        * establish a UNIT ATTENTION with PREVIOUS RESERVATION
-        * CONFLICT STATUS.
-        *
-        * See spc4r17, section 7.4.6 Control Mode Page, Table 349
-        */
-       if (cmd->se_sess &&
-           cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
-               core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
-                       cmd->orig_fe_lun, 0x2C,
-                       ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
-       return -EINVAL;
-}
-
 static inline long long transport_dev_end_lba(struct se_device *dev)
 {
        return dev->transport->get_blocks(dev) + 1;
@@ -2916,8 +2472,6 @@ static int transport_generic_cmd_sequencer(
         * Check for an existing UNIT ATTENTION condition
         */
        if (core_scsi3_ua_check(cmd, cdb) < 0) {
-               cmd->transport_wait_for_tasks =
-                               &transport_nop_wait_for_tasks;
                cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
                cmd->scsi_sense_reason = TCM_CHECK_CONDITION_UNIT_ATTENTION;
                return -EINVAL;
@@ -2927,7 +2481,6 @@ static int transport_generic_cmd_sequencer(
         */
        ret = su_dev->t10_alua.alua_state_check(cmd, cdb, &alua_ascq);
        if (ret != 0) {
-               cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
                /*
                 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
                 * The ALUA additional sense code qualifier (ASCQ) is determined
@@ -2951,8 +2504,12 @@ static int transport_generic_cmd_sequencer(
         */
        if (su_dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type) != 0) {
                if (su_dev->t10_pr.pr_ops.t10_seq_non_holder(
-                                       cmd, cdb, pr_reg_type) != 0)
-                       return transport_handle_reservation_conflict(cmd);
+                                       cmd, cdb, pr_reg_type) != 0) {
+                       cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
+                       cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
+                       cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
+                       return -EBUSY;
+               }
                /*
                 * This means the CDB is allowed for the SCSI Initiator port
                 * when said port is *NOT* holding the legacy SPC-2 or
@@ -2960,13 +2517,19 @@ static int transport_generic_cmd_sequencer(
                 */
        }
 
+       /*
+        * If we operate in passthrough mode we skip most CDB emulation and
+        * instead hand the commands down to the physical SCSI device.
+        */
+       passthrough =
+               (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV);
+
        switch (cdb[0]) {
        case READ_6:
                sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_6;
                cmd->t_task_lba = transport_lba_21(cdb);
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
@@ -2975,7 +2538,6 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_10;
                cmd->t_task_lba = transport_lba_32(cdb);
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
@@ -2984,7 +2546,6 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_12;
                cmd->t_task_lba = transport_lba_32(cdb);
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
@@ -2993,7 +2554,6 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_16;
                cmd->t_task_lba = transport_lba_64(cdb);
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
@@ -3002,7 +2562,6 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_6;
                cmd->t_task_lba = transport_lba_21(cdb);
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
@@ -3011,9 +2570,9 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_10;
                cmd->t_task_lba = transport_lba_32(cdb);
-               cmd->t_tasks_fua = (cdb[1] & 0x8);
+               if (cdb[1] & 0x8)
+                       cmd->se_cmd_flags |= SCF_FUA;
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
        case WRITE_12:
@@ -3021,9 +2580,9 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_12;
                cmd->t_task_lba = transport_lba_32(cdb);
-               cmd->t_tasks_fua = (cdb[1] & 0x8);
+               if (cdb[1] & 0x8)
+                       cmd->se_cmd_flags |= SCF_FUA;
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
        case WRITE_16:
@@ -3031,44 +2590,37 @@ static int transport_generic_cmd_sequencer(
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_16;
                cmd->t_task_lba = transport_lba_64(cdb);
-               cmd->t_tasks_fua = (cdb[1] & 0x8);
+               if (cdb[1] & 0x8)
+                       cmd->se_cmd_flags |= SCF_FUA;
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
                break;
        case XDWRITEREAD_10:
                if ((cmd->data_direction != DMA_TO_DEVICE) ||
-                   !(cmd->t_tasks_bidi))
+                   !(cmd->se_cmd_flags & SCF_BIDI))
                        goto out_invalid_cdb_field;
                sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
                if (sector_ret)
                        goto out_unsupported_cdb;
                size = transport_get_size(sectors, cdb, cmd);
-               cmd->transport_split_cdb = &split_cdb_XX_10;
                cmd->t_task_lba = transport_lba_32(cdb);
                cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
-               passthrough = (dev->transport->transport_type ==
-                               TRANSPORT_PLUGIN_PHBA_PDEV);
+
                /*
-                * Skip the remaining assignments for TCM/PSCSI passthrough
+                * Do now allow BIDI commands for passthrough mode.
                 */
                if (passthrough)
-                       break;
+                       goto out_unsupported_cdb;
+
                /*
-                * Setup BIDI XOR callback to be run during transport_generic_complete_ok()
+                * Setup BIDI XOR callback to be run after I/O completion.
                 */
                cmd->transport_complete_callback = &transport_xor_callback;
-               cmd->t_tasks_fua = (cdb[1] & 0x8);
+               if (cdb[1] & 0x8)
+                       cmd->se_cmd_flags |= SCF_FUA;
                break;
        case VARIABLE_LENGTH_CMD:
                service_action = get_unaligned_be16(&cdb[8]);
-               /*
-                * Determine if this is TCM/PSCSI device and we should disable
-                * internal emulation for this CDB.
-                */
-               passthrough = (dev->transport->transport_type ==
-                                       TRANSPORT_PLUGIN_PHBA_PDEV);
-
                switch (service_action) {
                case XDWRITEREAD_32:
                        sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
@@ -3079,22 +2631,22 @@ static int transport_generic_cmd_sequencer(
                         * Use WRITE_32 and READ_32 opcodes for the emulated
                         * XDWRITE_READ_32 logic.
                         */
-                       cmd->transport_split_cdb = &split_cdb_XX_32;
                        cmd->t_task_lba = transport_lba_64_ext(cdb);
                        cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
 
                        /*
-                        * Skip the remaining assignments for TCM/PSCSI passthrough
+                        * Do now allow BIDI commands for passthrough mode.
                         */
                        if (passthrough)
-                               break;
+                               goto out_unsupported_cdb;
 
                        /*
-                        * Setup BIDI XOR callback to be run during
-                        * transport_generic_complete_ok()
+                        * Setup BIDI XOR callback to be run during after I/O
+                        * completion.
                         */
                        cmd->transport_complete_callback = &transport_xor_callback;
-                       cmd->t_tasks_fua = (cdb[10] & 0x8);
+                       if (cdb[1] & 0x8)
+                               cmd->se_cmd_flags |= SCF_FUA;
                        break;
                case WRITE_SAME_32:
                        sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
@@ -3114,7 +2666,8 @@ static int transport_generic_cmd_sequencer(
 
                        if (target_check_write_same_discard(&cdb[10], dev) < 0)
                                goto out_invalid_cdb_field;
-
+                       if (!passthrough)
+                               cmd->execute_task = target_emulate_write_same;
                        break;
                default:
                        pr_err("VARIABLE_LENGTH_CMD service action"
@@ -3128,12 +2681,10 @@ static int transport_generic_cmd_sequencer(
                        /*
                         * Check for emulated MI_REPORT_TARGET_PGS.
                         */
-                       if (cdb[1] == MI_REPORT_TARGET_PGS) {
-                               cmd->transport_emulate_cdb =
-                               (su_dev->t10_alua.alua_type ==
-                                SPC3_ALUA_EMULATED) ?
-                               core_emulate_report_target_port_groups :
-                               NULL;
+                       if (cdb[1] == MI_REPORT_TARGET_PGS &&
+                           su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
+                               cmd->execute_task =
+                                       target_emulate_report_target_port_groups;
                        }
                        size = (cdb[6] << 24) | (cdb[7] << 16) |
                               (cdb[8] << 8) | cdb[9];
@@ -3154,8 +2705,15 @@ static int transport_generic_cmd_sequencer(
        case MODE_SENSE:
                size = cdb[4];
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_modesense;
                break;
        case MODE_SENSE_10:
+               size = (cdb[7] << 8) + cdb[8];
+               cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_modesense;
+               break;
        case GPCMD_READ_BUFFER_CAPACITY:
        case GPCMD_SEND_OPC:
        case LOG_SELECT:
@@ -3175,11 +2733,14 @@ static int transport_generic_cmd_sequencer(
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
                break;
        case PERSISTENT_RESERVE_IN:
+               if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
+                       cmd->execute_task = target_scsi3_emulate_pr_in;
+               size = (cdb[7] << 8) + cdb[8];
+               cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               break;
        case PERSISTENT_RESERVE_OUT:
-               cmd->transport_emulate_cdb =
-                       (su_dev->t10_pr.res_type ==
-                        SPC3_PERSISTENT_RESERVATIONS) ?
-                       core_scsi3_emulate_pr : NULL;
+               if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
+                       cmd->execute_task = target_scsi3_emulate_pr_out;
                size = (cdb[7] << 8) + cdb[8];
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
                break;
@@ -3198,12 +2759,10 @@ static int transport_generic_cmd_sequencer(
                         *
                         * Check for emulated MO_SET_TARGET_PGS.
                         */
-                       if (cdb[1] == MO_SET_TARGET_PGS) {
-                               cmd->transport_emulate_cdb =
-                               (su_dev->t10_alua.alua_type ==
-                                       SPC3_ALUA_EMULATED) ?
-                               core_emulate_set_target_port_groups :
-                               NULL;
+                       if (cdb[1] == MO_SET_TARGET_PGS &&
+                           su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
+                               cmd->execute_task =
+                                       target_emulate_set_target_port_groups;
                        }
 
                        size = (cdb[6] << 24) | (cdb[7] << 16) |
@@ -3223,6 +2782,8 @@ static int transport_generic_cmd_sequencer(
                if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
                        cmd->sam_task_attr = MSG_HEAD_TAG;
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_inquiry;
                break;
        case READ_BUFFER:
                size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
@@ -3231,6 +2792,8 @@ static int transport_generic_cmd_sequencer(
        case READ_CAPACITY:
                size = READ_CAP_LEN;
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_readcapacity;
                break;
        case READ_MEDIA_SERIAL_NUMBER:
        case SECURITY_PROTOCOL_IN:
@@ -3239,6 +2802,21 @@ static int transport_generic_cmd_sequencer(
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
                break;
        case SERVICE_ACTION_IN:
+               switch (cmd->t_task_cdb[1] & 0x1f) {
+               case SAI_READ_CAPACITY_16:
+                       if (!passthrough)
+                               cmd->execute_task =
+                                       target_emulate_readcapacity_16;
+                       break;
+               default:
+                       if (passthrough)
+                               break;
+
+                       pr_err("Unsupported SA: 0x%02x\n",
+                               cmd->t_task_cdb[1] & 0x1f);
+                       goto out_unsupported_cdb;
+               }
+               /*FALLTHROUGH*/
        case ACCESS_CONTROL_IN:
        case ACCESS_CONTROL_OUT:
        case EXTENDED_COPY:
@@ -3269,6 +2847,8 @@ static int transport_generic_cmd_sequencer(
        case REQUEST_SENSE:
                size = cdb[4];
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_request_sense;
                break;
        case READ_ELEMENT_STATUS:
                size = 65536 * cdb[7] + 256 * cdb[8] + cdb[9];
@@ -3296,10 +2876,8 @@ static int transport_generic_cmd_sequencer(
                 * is running in SPC_PASSTHROUGH, and wants reservations
                 * emulation disabled.
                 */
-               cmd->transport_emulate_cdb =
-                               (su_dev->t10_pr.res_type !=
-                                SPC_PASSTHROUGH) ?
-                               core_scsi2_emulate_crh : NULL;
+               if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
+                       cmd->execute_task = target_scsi2_reservation_reserve;
                cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
                break;
        case RELEASE:
@@ -3313,10 +2891,8 @@ static int transport_generic_cmd_sequencer(
                else
                        size = cmd->data_length;
 
-               cmd->transport_emulate_cdb =
-                               (su_dev->t10_pr.res_type !=
-                                SPC_PASSTHROUGH) ?
-                               core_scsi2_emulate_crh : NULL;
+               if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
+                       cmd->execute_task = target_scsi2_reservation_release;
                cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
                break;
        case SYNCHRONIZE_CACHE:
@@ -3337,16 +2913,9 @@ static int transport_generic_cmd_sequencer(
                size = transport_get_size(sectors, cdb, cmd);
                cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
 
-               /*
-                * For TCM/pSCSI passthrough, skip cmd->transport_emulate_cdb()
-                */
-               if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
+               if (passthrough)
                        break;
-               /*
-                * Set SCF_EMULATE_CDB_ASYNC to ensure asynchronous operation
-                * for SYNCHRONIZE_CACHE* Immed=1 case in __transport_execute_tasks()
-                */
-               cmd->se_cmd_flags |= SCF_EMULATE_CDB_ASYNC;
+
                /*
                 * Check to ensure that LBA + Range does not exceed past end of
                 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
@@ -3355,10 +2924,13 @@ static int transport_generic_cmd_sequencer(
                        if (transport_cmd_get_valid_sectors(cmd) < 0)
                                goto out_invalid_cdb_field;
                }
+               cmd->execute_task = target_emulate_synchronize_cache;
                break;
        case UNMAP:
                size = get_unaligned_be16(&cdb[7]);
                cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_unmap;
                break;
        case WRITE_SAME_16:
                sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
@@ -3377,6 +2949,8 @@ static int transport_generic_cmd_sequencer(
 
                if (target_check_write_same_discard(&cdb[1], dev) < 0)
                        goto out_invalid_cdb_field;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_write_same;
                break;
        case WRITE_SAME:
                sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
@@ -3398,26 +2972,31 @@ static int transport_generic_cmd_sequencer(
                 */
                if (target_check_write_same_discard(&cdb[1], dev) < 0)
                        goto out_invalid_cdb_field;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_write_same;
                break;
        case ALLOW_MEDIUM_REMOVAL:
-       case GPCMD_CLOSE_TRACK:
        case ERASE:
-       case INITIALIZE_ELEMENT_STATUS:
-       case GPCMD_LOAD_UNLOAD:
        case REZERO_UNIT:
        case SEEK_10:
-       case GPCMD_SET_SPEED:
        case SPACE:
        case START_STOP:
        case TEST_UNIT_READY:
        case VERIFY:
        case WRITE_FILEMARKS:
+               cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
+               if (!passthrough)
+                       cmd->execute_task = target_emulate_noop;
+               break;
+       case GPCMD_CLOSE_TRACK:
+       case INITIALIZE_ELEMENT_STATUS:
+       case GPCMD_LOAD_UNLOAD:
+       case GPCMD_SET_SPEED:
        case MOVE_MEDIUM:
                cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
                break;
        case REPORT_LUNS:
-               cmd->transport_emulate_cdb =
-                               transport_core_report_lun_response;
+               cmd->execute_task = target_report_luns;
                size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
                /*
                 * Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
@@ -3431,7 +3010,6 @@ static int transport_generic_cmd_sequencer(
                pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
                        " 0x%02x, sending CHECK_CONDITION.\n",
                        cmd->se_tfo->get_fabric_name(), cdb[0]);
-               cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
                goto out_unsupported_cdb;
        }
 
@@ -3470,6 +3048,11 @@ static int transport_generic_cmd_sequencer(
                cmd->data_length = size;
        }
 
+       /* reject any command that we don't have a handler for */
+       if (!(passthrough || cmd->execute_task ||
+            (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
+               goto out_unsupported_cdb;
+
        /* Let's limit control cdbs to a page, for simplicity's sake. */
        if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
            size > PAGE_SIZE)
@@ -3489,8 +3072,7 @@ out_invalid_cdb_field:
 }
 
 /*
- * Called from transport_generic_complete_ok() and
- * transport_generic_request_failure() to determine which dormant/delayed
+ * Called from I/O completion to determine which dormant/delayed
  * and ordered cmds need to have their tasks added to the execution queue.
  */
 static void transport_complete_task_attr(struct se_cmd *cmd)
@@ -3507,18 +3089,13 @@ static void transport_complete_task_attr(struct se_cmd *cmd)
                        " SIMPLE: %u\n", dev->dev_cur_ordered_id,
                        cmd->se_ordered_id);
        } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
-               atomic_dec(&dev->dev_hoq_count);
-               smp_mb__after_atomic_dec();
                dev->dev_cur_ordered_id++;
                pr_debug("Incremented dev_cur_ordered_id: %u for"
                        " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
                        cmd->se_ordered_id);
        } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
-               spin_lock(&dev->ordered_cmd_lock);
-               list_del(&cmd->se_ordered_node);
                atomic_dec(&dev->dev_ordered_sync);
                smp_mb__after_atomic_dec();
-               spin_unlock(&dev->ordered_cmd_lock);
 
                dev->dev_cur_ordered_id++;
                pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
@@ -3558,12 +3135,18 @@ static void transport_complete_task_attr(struct se_cmd *cmd)
                wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
 }
 
-static int transport_complete_qf(struct se_cmd *cmd)
+static void transport_complete_qf(struct se_cmd *cmd)
 {
        int ret = 0;
 
-       if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
-               return cmd->se_tfo->queue_status(cmd);
+       if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
+               transport_complete_task_attr(cmd);
+
+       if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
+               ret = cmd->se_tfo->queue_status(cmd);
+               if (ret)
+                       goto out;
+       }
 
        switch (cmd->data_direction) {
        case DMA_FROM_DEVICE:
@@ -3573,7 +3156,7 @@ static int transport_complete_qf(struct se_cmd *cmd)
                if (cmd->t_bidi_data_sg) {
                        ret = cmd->se_tfo->queue_data_in(cmd);
                        if (ret < 0)
-                               return ret;
+                               break;
                }
                /* Fall through for DMA_TO_DEVICE */
        case DMA_NONE:
@@ -3583,17 +3166,20 @@ static int transport_complete_qf(struct se_cmd *cmd)
                break;
        }
 
-       return ret;
+out:
+       if (ret < 0) {
+               transport_handle_queue_full(cmd, cmd->se_dev);
+               return;
+       }
+       transport_lun_remove_cmd(cmd);
+       transport_cmd_check_stop_to_fabric(cmd);
 }
 
 static void transport_handle_queue_full(
        struct se_cmd *cmd,
-       struct se_device *dev,
-       int (*qf_callback)(struct se_cmd *))
+       struct se_device *dev)
 {
        spin_lock_irq(&dev->qf_cmd_lock);
-       cmd->se_cmd_flags |= SCF_EMULATE_QUEUE_FULL;
-       cmd->transport_qf_callback = qf_callback;
        list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
        atomic_inc(&dev->dev_qf_count);
        smp_mb__after_atomic_inc();
@@ -3602,9 +3188,11 @@ static void transport_handle_queue_full(
        schedule_work(&cmd->se_dev->qf_work_queue);
 }
 
-static void transport_generic_complete_ok(struct se_cmd *cmd)
+static void target_complete_ok_work(struct work_struct *work)
 {
+       struct se_cmd *cmd = container_of(work, struct se_cmd, work);
        int reason = 0, ret;
+
        /*
         * Check if we need to move delayed/dormant tasks from cmds on the
         * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
@@ -3619,14 +3207,6 @@ static void transport_generic_complete_ok(struct se_cmd *cmd)
        if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
                schedule_work(&cmd->se_dev->qf_work_queue);
 
-       if (cmd->transport_qf_callback) {
-               ret = cmd->transport_qf_callback(cmd);
-               if (ret < 0)
-                       goto queue_full;
-
-               cmd->transport_qf_callback = NULL;
-               goto done;
-       }
        /*
         * Check if we need to retrieve a sense buffer from
         * the struct se_cmd in question.
@@ -3642,7 +3222,7 @@ static void transport_generic_complete_ok(struct se_cmd *cmd)
                if (cmd->scsi_status) {
                        ret = transport_send_check_condition_and_sense(
                                        cmd, reason, 1);
-                       if (ret == -EAGAIN)
+                       if (ret == -EAGAIN || ret == -ENOMEM)
                                goto queue_full;
 
                        transport_lun_remove_cmd(cmd);
@@ -3667,7 +3247,7 @@ static void transport_generic_complete_ok(struct se_cmd *cmd)
                spin_unlock(&cmd->se_lun->lun_sep_lock);
 
                ret = cmd->se_tfo->queue_data_in(cmd);
-               if (ret == -EAGAIN)
+               if (ret == -EAGAIN || ret == -ENOMEM)
                        goto queue_full;
                break;
        case DMA_TO_DEVICE:
@@ -3688,21 +3268,20 @@ static void transport_generic_complete_ok(struct se_cmd *cmd)
                        }
                        spin_unlock(&cmd->se_lun->lun_sep_lock);
                        ret = cmd->se_tfo->queue_data_in(cmd);
-                       if (ret == -EAGAIN)
+                       if (ret == -EAGAIN || ret == -ENOMEM)
                                goto queue_full;
                        break;
                }
                /* Fall through for DMA_TO_DEVICE */
        case DMA_NONE:
                ret = cmd->se_tfo->queue_status(cmd);
-               if (ret == -EAGAIN)
+               if (ret == -EAGAIN || ret == -ENOMEM)
                        goto queue_full;
                break;
        default:
                break;
        }
 
-done:
        transport_lun_remove_cmd(cmd);
        transport_cmd_check_stop_to_fabric(cmd);
        return;
@@ -3710,34 +3289,35 @@ done:
 queue_full:
        pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
                " data_direction: %d\n", cmd, cmd->data_direction);
-       transport_handle_queue_full(cmd, cmd->se_dev, transport_complete_qf);
+       cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
+       transport_handle_queue_full(cmd, cmd->se_dev);
 }
 
 static void transport_free_dev_tasks(struct se_cmd *cmd)
 {
        struct se_task *task, *task_tmp;
        unsigned long flags;
+       LIST_HEAD(dispose_list);
 
        spin_lock_irqsave(&cmd->t_state_lock, flags);
        list_for_each_entry_safe(task, task_tmp,
                                &cmd->t_task_list, t_list) {
-               if (atomic_read(&task->task_active))
-                       continue;
+               if (!(task->task_flags & TF_ACTIVE))
+                       list_move_tail(&task->t_list, &dispose_list);
+       }
+       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-               kfree(task->task_sg_bidi);
-               kfree(task->task_sg);
+       while (!list_empty(&dispose_list)) {
+               task = list_first_entry(&dispose_list, struct se_task, t_list);
+
+               if (task->task_sg != cmd->t_data_sg &&
+                   task->task_sg != cmd->t_bidi_data_sg)
+                       kfree(task->task_sg);
 
                list_del(&task->t_list);
 
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               if (task->se_dev)
-                       task->se_dev->transport->free_task(task);
-               else
-                       pr_err("task[%u] - task->se_dev is NULL\n",
-                               task->task_no);
-               spin_lock_irqsave(&cmd->t_state_lock, flags);
+               cmd->se_dev->transport->free_task(task);
        }
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 }
 
 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
@@ -3765,115 +3345,81 @@ static inline void transport_free_pages(struct se_cmd *cmd)
        cmd->t_bidi_data_nents = 0;
 }
 
-static inline void transport_release_tasks(struct se_cmd *cmd)
-{
-       transport_free_dev_tasks(cmd);
-}
-
-static inline int transport_dec_and_check(struct se_cmd *cmd)
+/**
+ * transport_put_cmd - release a reference to a command
+ * @cmd:       command to release
+ *
+ * This routine releases our reference to the command and frees it if possible.
+ */
+static void transport_put_cmd(struct se_cmd *cmd)
 {
        unsigned long flags;
+       int free_tasks = 0;
 
        spin_lock_irqsave(&cmd->t_state_lock, flags);
        if (atomic_read(&cmd->t_fe_count)) {
-               if (!atomic_dec_and_test(&cmd->t_fe_count)) {
-                       spin_unlock_irqrestore(&cmd->t_state_lock,
-                                       flags);
-                       return 1;
-               }
+               if (!atomic_dec_and_test(&cmd->t_fe_count))
+                       goto out_busy;
        }
 
        if (atomic_read(&cmd->t_se_count)) {
-               if (!atomic_dec_and_test(&cmd->t_se_count)) {
-                       spin_unlock_irqrestore(&cmd->t_state_lock,
-                                       flags);
-                       return 1;
-               }
+               if (!atomic_dec_and_test(&cmd->t_se_count))
+                       goto out_busy;
        }
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
-       return 0;
-}
-
-static void transport_release_fe_cmd(struct se_cmd *cmd)
-{
-       unsigned long flags;
 
-       if (transport_dec_and_check(cmd))
-               return;
-
-       spin_lock_irqsave(&cmd->t_state_lock, flags);
-       if (!atomic_read(&cmd->transport_dev_active)) {
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               goto free_pages;
+       if (atomic_read(&cmd->transport_dev_active)) {
+               atomic_set(&cmd->transport_dev_active, 0);
+               transport_all_task_dev_remove_state(cmd);
+               free_tasks = 1;
        }
-       atomic_set(&cmd->transport_dev_active, 0);
-       transport_all_task_dev_remove_state(cmd);
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-       transport_release_tasks(cmd);
-free_pages:
+       if (free_tasks != 0)
+               transport_free_dev_tasks(cmd);
+
        transport_free_pages(cmd);
-       transport_free_se_cmd(cmd);
-       cmd->se_tfo->release_cmd(cmd);
+       transport_release_cmd(cmd);
+       return;
+out_busy:
+       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 }
 
-static int
-transport_generic_remove(struct se_cmd *cmd, int session_reinstatement)
-{
-       unsigned long flags;
-
-       if (transport_dec_and_check(cmd)) {
-               if (session_reinstatement) {
-                       spin_lock_irqsave(&cmd->t_state_lock, flags);
-                       transport_all_task_dev_remove_state(cmd);
-                       spin_unlock_irqrestore(&cmd->t_state_lock,
-                                       flags);
-               }
-               return 1;
-       }
-
-       spin_lock_irqsave(&cmd->t_state_lock, flags);
-       if (!atomic_read(&cmd->transport_dev_active)) {
-               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-               goto free_pages;
-       }
-       atomic_set(&cmd->transport_dev_active, 0);
-       transport_all_task_dev_remove_state(cmd);
-       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-
-       transport_release_tasks(cmd);
-
-free_pages:
-       transport_free_pages(cmd);
-       transport_release_cmd(cmd);
-       return 0;
-}
-
-/*
- * transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
- * allocating in the core.
- * @cmd:  Associated se_cmd descriptor
- * @mem:  SGL style memory for TCM WRITE / READ
- * @sg_mem_num: Number of SGL elements
- * @mem_bidi_in: SGL style memory for TCM BIDI READ
- * @sg_mem_bidi_num: Number of BIDI READ SGL elements
- *
- * Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
- * of parameters.
- */
-int transport_generic_map_mem_to_cmd(
-       struct se_cmd *cmd,
-       struct scatterlist *sgl,
-       u32 sgl_count,
-       struct scatterlist *sgl_bidi,
-       u32 sgl_bidi_count)
+/*
+ * transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
+ * allocating in the core.
+ * @cmd:  Associated se_cmd descriptor
+ * @mem:  SGL style memory for TCM WRITE / READ
+ * @sg_mem_num: Number of SGL elements
+ * @mem_bidi_in: SGL style memory for TCM BIDI READ
+ * @sg_mem_bidi_num: Number of BIDI READ SGL elements
+ *
+ * Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
+ * of parameters.
+ */
+int transport_generic_map_mem_to_cmd(
+       struct se_cmd *cmd,
+       struct scatterlist *sgl,
+       u32 sgl_count,
+       struct scatterlist *sgl_bidi,
+       u32 sgl_bidi_count)
 {
        if (!sgl || !sgl_count)
                return 0;
 
        if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) ||
            (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) {
+               /*
+                * Reject SCSI data overflow with map_mem_to_cmd() as incoming
+                * scatterlists already have been set to follow what the fabric
+                * passes for the original expected data transfer length.
+                */
+               if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
+                       pr_warn("Rejecting SCSI DATA overflow for fabric using"
+                               " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
+                       cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
+                       cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
+                       return -EINVAL;
+               }
 
                cmd->t_data_sg = sgl;
                cmd->t_data_nents = sgl_count;
@@ -3889,62 +3435,6 @@ int transport_generic_map_mem_to_cmd(
 }
 EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
 
-static int transport_new_cmd_obj(struct se_cmd *cmd)
-{
-       struct se_device *dev = cmd->se_dev;
-       int set_counts = 1, rc, task_cdbs;
-
-       /*
-        * Setup any BIDI READ tasks and memory from
-        * cmd->t_mem_bidi_list so the READ struct se_tasks
-        * are queued first for the non pSCSI passthrough case.
-        */
-       if (cmd->t_bidi_data_sg &&
-           (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV)) {
-               rc = transport_allocate_tasks(cmd,
-                                             cmd->t_task_lba,
-                                             DMA_FROM_DEVICE,
-                                             cmd->t_bidi_data_sg,
-                                             cmd->t_bidi_data_nents);
-               if (rc <= 0) {
-                       cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
-                       cmd->scsi_sense_reason =
-                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-                       return -EINVAL;
-               }
-               atomic_inc(&cmd->t_fe_count);
-               atomic_inc(&cmd->t_se_count);
-               set_counts = 0;
-       }
-       /*
-        * Setup the tasks and memory from cmd->t_mem_list
-        * Note for BIDI transfers this will contain the WRITE payload
-        */
-       task_cdbs = transport_allocate_tasks(cmd,
-                                            cmd->t_task_lba,
-                                            cmd->data_direction,
-                                            cmd->t_data_sg,
-                                            cmd->t_data_nents);
-       if (task_cdbs <= 0) {
-               cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
-               cmd->scsi_sense_reason =
-                       TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-               return -EINVAL;
-       }
-
-       if (set_counts) {
-               atomic_inc(&cmd->t_fe_count);
-               atomic_inc(&cmd->t_se_count);
-       }
-
-       cmd->t_task_list_num = task_cdbs;
-
-       atomic_set(&cmd->t_task_cdbs_left, task_cdbs);
-       atomic_set(&cmd->t_task_cdbs_ex_left, task_cdbs);
-       atomic_set(&cmd->t_task_cdbs_timeout_left, task_cdbs);
-       return 0;
-}
-
 void *transport_kmap_first_data_page(struct se_cmd *cmd)
 {
        struct scatterlist *sg = cmd->t_data_sg;
@@ -4055,15 +3545,13 @@ void transport_do_task_sg_chain(struct se_cmd *cmd)
                /*
                 * For the padded tasks, use the extra SGL vector allocated
                 * in transport_allocate_data_tasks() for the sg_prev_nents
-                * offset into sg_chain() above..  The last task of a
-                * multi-task list, or a single task will not have
-                * task->task_sg_padded set..
+                * offset into sg_chain() above.
+                *
+                * We do not need the padding for the last task (or a single
+                * task), but in that case we will never use the sg_prev_nents
+                * value below which would be incorrect.
                 */
-               if (task->task_padded_sg)
-                       sg_prev_nents = (task->task_sg_nents + 1);
-               else
-                       sg_prev_nents = task->task_sg_nents;
-
+               sg_prev_nents = (task->task_sg_nents + 1);
                sg_prev = task->task_sg;
        }
        /*
@@ -4093,30 +3581,60 @@ EXPORT_SYMBOL(transport_do_task_sg_chain);
 /*
  * Break up cmd into chunks transport can handle
  */
-static int transport_allocate_data_tasks(
-       struct se_cmd *cmd,
-       unsigned long long lba,
+static int
+transport_allocate_data_tasks(struct se_cmd *cmd,
        enum dma_data_direction data_direction,
-       struct scatterlist *sgl,
-       unsigned int sgl_nents)
+       struct scatterlist *cmd_sg, unsigned int sgl_nents)
 {
-       unsigned char *cdb = NULL;
-       struct se_task *task;
        struct se_device *dev = cmd->se_dev;
-       unsigned long flags;
-       int task_count, i, ret;
-       sector_t sectors, dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
-       u32 sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
-       struct scatterlist *sg;
-       struct scatterlist *cmd_sg;
+       int task_count, i;
+       unsigned long long lba;
+       sector_t sectors, dev_max_sectors;
+       u32 sector_size;
+
+       if (transport_cmd_get_valid_sectors(cmd) < 0)
+               return -EINVAL;
+
+       dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
+       sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
 
        WARN_ON(cmd->data_length % sector_size);
+
+       lba = cmd->t_task_lba;
        sectors = DIV_ROUND_UP(cmd->data_length, sector_size);
        task_count = DIV_ROUND_UP_SECTOR_T(sectors, dev_max_sectors);
-       
-       cmd_sg = sgl;
+
+       /*
+        * If we need just a single task reuse the SG list in the command
+        * and avoid a lot of work.
+        */
+       if (task_count == 1) {
+               struct se_task *task;
+               unsigned long flags;
+
+               task = transport_generic_get_task(cmd, data_direction);
+               if (!task)
+                       return -ENOMEM;
+
+               task->task_sg = cmd_sg;
+               task->task_sg_nents = sgl_nents;
+
+               task->task_lba = lba;
+               task->task_sectors = sectors;
+               task->task_size = task->task_sectors * sector_size;
+
+               spin_lock_irqsave(&cmd->t_state_lock, flags);
+               list_add_tail(&task->t_list, &cmd->t_task_list);
+               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+
+               return task_count;
+       }
+
        for (i = 0; i < task_count; i++) {
+               struct se_task *task;
                unsigned int task_size, task_sg_nents_padded;
+               struct scatterlist *sg;
+               unsigned long flags;
                int count;
 
                task = transport_generic_get_task(cmd, data_direction);
@@ -4127,14 +3645,6 @@ static int transport_allocate_data_tasks(
                task->task_sectors = min(sectors, dev_max_sectors);
                task->task_size = task->task_sectors * sector_size;
 
-               cdb = dev->transport->get_cdb(task);
-               BUG_ON(!cdb);
-
-               memcpy(cdb, cmd->t_task_cdb,
-                      scsi_command_size(cmd->t_task_cdb));
-
-               /* Update new cdb with updated lba/sectors */
-               cmd->transport_split_cdb(task->task_lba, task->task_sectors, cdb);
                /*
                 * This now assumes that passed sg_ents are in PAGE_SIZE chunks
                 * in order to calculate the number per task SGL entries
@@ -4150,7 +3660,6 @@ static int transport_allocate_data_tasks(
                 */
                if (cmd->se_tfo->task_sg_chaining && (i < (task_count - 1))) {
                        task_sg_nents_padded = (task->task_sg_nents + 1);
-                       task->task_padded_sg = 1;
                } else
                        task_sg_nents_padded = task->task_sg_nents;
 
@@ -4182,20 +3691,6 @@ static int transport_allocate_data_tasks(
                list_add_tail(&task->t_list, &cmd->t_task_list);
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
        }
-       /*
-        * Now perform the memory map of task->task_sg[] into backend
-        * subsystem memory..
-        */
-       list_for_each_entry(task, &cmd->t_task_list, t_list) {
-               if (atomic_read(&task->task_sent))
-                       continue;
-               if (!dev->transport->map_data_SG)
-                       continue;
-
-               ret = dev->transport->map_data_SG(task);
-               if (ret < 0)
-                       return 0;
-       }
 
        return task_count;
 }
@@ -4203,30 +3698,14 @@ static int transport_allocate_data_tasks(
 static int
 transport_allocate_control_task(struct se_cmd *cmd)
 {
-       struct se_device *dev = cmd->se_dev;
-       unsigned char *cdb;
        struct se_task *task;
        unsigned long flags;
-       int ret = 0;
 
        task = transport_generic_get_task(cmd, cmd->data_direction);
        if (!task)
                return -ENOMEM;
 
-       cdb = dev->transport->get_cdb(task);
-       BUG_ON(!cdb);
-       memcpy(cdb, cmd->t_task_cdb,
-              scsi_command_size(cmd->t_task_cdb));
-
-       task->task_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
-                               GFP_KERNEL);
-       if (!task->task_sg) {
-               cmd->se_dev->transport->free_task(task);
-               return -ENOMEM;
-       }
-
-       memcpy(task->task_sg, cmd->t_data_sg,
-              sizeof(struct scatterlist) * cmd->t_data_nents);
+       task->task_sg = cmd->t_data_sg;
        task->task_size = cmd->data_length;
        task->task_sg_nents = cmd->t_data_nents;
 
@@ -4234,53 +3713,20 @@ transport_allocate_control_task(struct se_cmd *cmd)
        list_add_tail(&task->t_list, &cmd->t_task_list);
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-       if (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) {
-               if (dev->transport->map_control_SG)
-                       ret = dev->transport->map_control_SG(task);
-       } else if (cmd->se_cmd_flags & SCF_SCSI_NON_DATA_CDB) {
-               if (dev->transport->cdb_none)
-                       ret = dev->transport->cdb_none(task);
-       } else {
-               pr_err("target: Unknown control cmd type!\n");
-               BUG();
-       }
-
        /* Success! Return number of tasks allocated */
-       if (ret == 0)
-               return 1;
-       return ret;
-}
-
-static u32 transport_allocate_tasks(
-       struct se_cmd *cmd,
-       unsigned long long lba,
-       enum dma_data_direction data_direction,
-       struct scatterlist *sgl,
-       unsigned int sgl_nents)
-{
-       if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
-               if (transport_cmd_get_valid_sectors(cmd) < 0)
-                       return -EINVAL;
-
-               return transport_allocate_data_tasks(cmd, lba, data_direction,
-                                                    sgl, sgl_nents);
-       } else
-               return transport_allocate_control_task(cmd);
-
+       return 1;
 }
 
-
-/*      transport_generic_new_cmd(): Called from transport_processing_thread()
- *
- *      Allocate storage transport resources from a set of values predefined
- *      by transport_generic_cmd_sequencer() from the iSCSI Target RX process.
- *      Any non zero return here is treated as an "out of resource' op here.
+/*
+ * Allocate any required ressources to execute the command, and either place
+ * it on the execution queue if possible.  For writes we might not have the
+ * payload yet, thus notify the fabric via a call to ->write_pending instead.
  */
-       /*
-        * Generate struct se_task(s) and/or their payloads for this CDB.
-        */
 int transport_generic_new_cmd(struct se_cmd *cmd)
 {
+       struct se_device *dev = cmd->se_dev;
+       int task_cdbs, task_cdbs_bidi = 0;
+       int set_counts = 1;
        int ret = 0;
 
        /*
@@ -4292,18 +3738,54 @@ int transport_generic_new_cmd(struct se_cmd *cmd)
            cmd->data_length) {
                ret = transport_generic_get_mem(cmd);
                if (ret < 0)
-                       return ret;
+                       goto out_fail;
        }
+
        /*
-        * Call transport_new_cmd_obj() to invoke transport_allocate_tasks() for
-        * control or data CDB types, and perform the map to backend subsystem
-        * code from SGL memory allocated here by transport_generic_get_mem(), or
-        * via pre-existing SGL memory setup explictly by fabric module code with
-        * transport_generic_map_mem_to_cmd().
+        * For BIDI command set up the read tasks first.
         */
-       ret = transport_new_cmd_obj(cmd);
-       if (ret < 0)
-               return ret;
+       if (cmd->t_bidi_data_sg &&
+           dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
+               BUG_ON(!(cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB));
+
+               task_cdbs_bidi = transport_allocate_data_tasks(cmd,
+                               DMA_FROM_DEVICE, cmd->t_bidi_data_sg,
+                               cmd->t_bidi_data_nents);
+               if (task_cdbs_bidi <= 0)
+                       goto out_fail;
+
+               atomic_inc(&cmd->t_fe_count);
+               atomic_inc(&cmd->t_se_count);
+               set_counts = 0;
+       }
+
+       if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
+               task_cdbs = transport_allocate_data_tasks(cmd,
+                                       cmd->data_direction, cmd->t_data_sg,
+                                       cmd->t_data_nents);
+       } else {
+               task_cdbs = transport_allocate_control_task(cmd);
+       }
+
+       if (task_cdbs < 0)
+               goto out_fail;
+       else if (!task_cdbs && (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)) {
+               cmd->t_state = TRANSPORT_COMPLETE;
+               atomic_set(&cmd->t_transport_active, 1);
+               INIT_WORK(&cmd->work, target_complete_ok_work);
+               queue_work(target_completion_wq, &cmd->work);
+               return 0;
+       }
+
+       if (set_counts) {
+               atomic_inc(&cmd->t_fe_count);
+               atomic_inc(&cmd->t_se_count);
+       }
+
+       cmd->t_task_list_num = (task_cdbs + task_cdbs_bidi);
+       atomic_set(&cmd->t_task_cdbs_left, cmd->t_task_list_num);
+       atomic_set(&cmd->t_task_cdbs_ex_left, cmd->t_task_list_num);
+
        /*
         * For WRITEs, let the fabric know its buffer is ready..
         * This WRITE struct se_cmd (and all of its associated struct se_task's)
@@ -4321,6 +3803,11 @@ int transport_generic_new_cmd(struct se_cmd *cmd)
         */
        transport_execute_tasks(cmd);
        return 0;
+
+out_fail:
+       cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
+       cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+       return -EINVAL;
 }
 EXPORT_SYMBOL(transport_generic_new_cmd);
 
@@ -4334,15 +3821,18 @@ void transport_generic_process_write(struct se_cmd *cmd)
 }
 EXPORT_SYMBOL(transport_generic_process_write);
 
-static int transport_write_pending_qf(struct se_cmd *cmd)
+static void transport_write_pending_qf(struct se_cmd *cmd)
 {
-       return cmd->se_tfo->write_pending(cmd);
+       int ret;
+
+       ret = cmd->se_tfo->write_pending(cmd);
+       if (ret == -EAGAIN || ret == -ENOMEM) {
+               pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
+                        cmd);
+               transport_handle_queue_full(cmd, cmd->se_dev);
+       }
 }
 
-/*     transport_generic_write_pending():
- *
- *
- */
 static int transport_generic_write_pending(struct se_cmd *cmd)
 {
        unsigned long flags;
@@ -4352,17 +3842,6 @@ static int transport_generic_write_pending(struct se_cmd *cmd)
        cmd->t_state = TRANSPORT_WRITE_PENDING;
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
-       if (cmd->transport_qf_callback) {
-               ret = cmd->transport_qf_callback(cmd);
-               if (ret == -EAGAIN)
-                       goto queue_full;
-               else if (ret < 0)
-                       return ret;
-
-               cmd->transport_qf_callback = NULL;
-               return 0;
-       }
-
        /*
         * Clear the se_cmd for WRITE_PENDING status in order to set
         * cmd->t_transport_active=0 so that transport_generic_handle_data
@@ -4377,70 +3856,177 @@ static int transport_generic_write_pending(struct se_cmd *cmd)
         * frontend know that WRITE buffers are ready.
         */
        ret = cmd->se_tfo->write_pending(cmd);
-       if (ret == -EAGAIN)
+       if (ret == -EAGAIN || ret == -ENOMEM)
                goto queue_full;
        else if (ret < 0)
                return ret;
 
-       return PYX_TRANSPORT_WRITE_PENDING;
+       return 1;
 
 queue_full:
        pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
        cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
-       transport_handle_queue_full(cmd, cmd->se_dev,
-                       transport_write_pending_qf);
-       return ret;
+       transport_handle_queue_full(cmd, cmd->se_dev);
+       return 0;
 }
 
+/**
+ * transport_release_cmd - free a command
+ * @cmd:       command to free
+ *
+ * This routine unconditionally frees a command, and reference counting
+ * or list removal must be done in the caller.
+ */
 void transport_release_cmd(struct se_cmd *cmd)
 {
        BUG_ON(!cmd->se_tfo);
 
-       transport_free_se_cmd(cmd);
+       if (cmd->se_tmr_req)
+               core_tmr_release_req(cmd->se_tmr_req);
+       if (cmd->t_task_cdb != cmd->__t_task_cdb)
+               kfree(cmd->t_task_cdb);
+       /*
+        * Check if target_wait_for_sess_cmds() is expecting to
+        * release se_cmd directly here..
+        */
+       if (cmd->check_release != 0 && cmd->se_tfo->check_release_cmd)
+               if (cmd->se_tfo->check_release_cmd(cmd) != 0)
+                       return;
+
        cmd->se_tfo->release_cmd(cmd);
 }
 EXPORT_SYMBOL(transport_release_cmd);
 
-/*     transport_generic_free_cmd():
- *
- *     Called from processing frontend to release storage engine resources
- */
-void transport_generic_free_cmd(
-       struct se_cmd *cmd,
-       int wait_for_tasks,
-       int session_reinstatement)
+void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 {
-       if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD))
+       if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
+               if (wait_for_tasks && cmd->se_tmr_req)
+                        transport_wait_for_tasks(cmd);
+
                transport_release_cmd(cmd);
-       else {
+       } else {
+               if (wait_for_tasks)
+                       transport_wait_for_tasks(cmd);
+
                core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
 
-               if (cmd->se_lun) {
-#if 0
-                       pr_debug("cmd: %p ITT: 0x%08x contains"
-                               " cmd->se_lun\n", cmd,
-                               cmd->se_tfo->get_task_tag(cmd));
-#endif
+               if (cmd->se_lun)
                        transport_lun_remove_cmd(cmd);
-               }
-
-               if (wait_for_tasks && cmd->transport_wait_for_tasks)
-                       cmd->transport_wait_for_tasks(cmd, 0, 0);
 
                transport_free_dev_tasks(cmd);
 
-               transport_generic_remove(cmd, session_reinstatement);
+               transport_put_cmd(cmd);
        }
 }
 EXPORT_SYMBOL(transport_generic_free_cmd);
 
-static void transport_nop_wait_for_tasks(
-       struct se_cmd *cmd,
-       int remove_cmd,
-       int session_reinstatement)
+/* target_get_sess_cmd - Add command to active ->sess_cmd_list
+ * @se_sess:   session to reference
+ * @se_cmd:    command descriptor to add
+ */
+void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
 {
-       return;
+       unsigned long flags;
+
+       spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
+       list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
+       se_cmd->check_release = 1;
+       spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
 }
+EXPORT_SYMBOL(target_get_sess_cmd);
+
+/* target_put_sess_cmd - Check for active I/O shutdown or list delete
+ * @se_sess:   session to reference
+ * @se_cmd:    command descriptor to drop
+ */
+int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
+       if (list_empty(&se_cmd->se_cmd_list)) {
+               spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+               WARN_ON(1);
+               return 0;
+       }
+
+       if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
+               spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+               complete(&se_cmd->cmd_wait_comp);
+               return 1;
+       }
+       list_del(&se_cmd->se_cmd_list);
+       spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+
+       return 0;
+}
+EXPORT_SYMBOL(target_put_sess_cmd);
+
+/* target_splice_sess_cmd_list - Split active cmds into sess_wait_list
+ * @se_sess:   session to split
+ */
+void target_splice_sess_cmd_list(struct se_session *se_sess)
+{
+       struct se_cmd *se_cmd;
+       unsigned long flags;
+
+       WARN_ON(!list_empty(&se_sess->sess_wait_list));
+       INIT_LIST_HEAD(&se_sess->sess_wait_list);
+
+       spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
+       se_sess->sess_tearing_down = 1;
+
+       list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
+
+       list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
+               se_cmd->cmd_wait_set = 1;
+
+       spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
+}
+EXPORT_SYMBOL(target_splice_sess_cmd_list);
+
+/* target_wait_for_sess_cmds - Wait for outstanding descriptors
+ * @se_sess:    session to wait for active I/O
+ * @wait_for_tasks:    Make extra transport_wait_for_tasks call
+ */
+void target_wait_for_sess_cmds(
+       struct se_session *se_sess,
+       int wait_for_tasks)
+{
+       struct se_cmd *se_cmd, *tmp_cmd;
+       bool rc = false;
+
+       list_for_each_entry_safe(se_cmd, tmp_cmd,
+                               &se_sess->sess_wait_list, se_cmd_list) {
+               list_del(&se_cmd->se_cmd_list);
+
+               pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
+                       " %d\n", se_cmd, se_cmd->t_state,
+                       se_cmd->se_tfo->get_cmd_state(se_cmd));
+
+               if (wait_for_tasks) {
+                       pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
+                               " fabric state: %d\n", se_cmd, se_cmd->t_state,
+                               se_cmd->se_tfo->get_cmd_state(se_cmd));
+
+                       rc = transport_wait_for_tasks(se_cmd);
+
+                       pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
+                               " fabric state: %d\n", se_cmd, se_cmd->t_state,
+                               se_cmd->se_tfo->get_cmd_state(se_cmd));
+               }
+
+               if (!rc) {
+                       wait_for_completion(&se_cmd->cmd_wait_comp);
+                       pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
+                               " fabric state: %d\n", se_cmd, se_cmd->t_state,
+                               se_cmd->se_tfo->get_cmd_state(se_cmd));
+               }
+
+               se_cmd->se_tfo->release_cmd(se_cmd);
+       }
+}
+EXPORT_SYMBOL(target_wait_for_sess_cmds);
 
 /*     transport_lun_wait_for_tasks():
  *
@@ -4480,7 +4066,7 @@ static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
                pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
                                cmd->se_tfo->get_task_tag(cmd));
        }
-       transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
+       transport_remove_cmd_from_queue(cmd);
 
        return 0;
 }
@@ -4611,22 +4197,30 @@ int transport_clear_lun_from_sessions(struct se_lun *lun)
        return 0;
 }
 
-/*     transport_generic_wait_for_tasks():
+/**
+ * transport_wait_for_tasks - wait for completion to occur
+ * @cmd:       command to wait
  *
- *     Called from frontend or passthrough context to wait for storage engine
- *     to pause and/or release frontend generated struct se_cmd.
+ * Called from frontend fabric context to wait for storage engine
+ * to pause and/or release frontend generated struct se_cmd.
  */
-static void transport_generic_wait_for_tasks(
-       struct se_cmd *cmd,
-       int remove_cmd,
-       int session_reinstatement)
+bool transport_wait_for_tasks(struct se_cmd *cmd)
 {
        unsigned long flags;
 
-       if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req))
-               return;
-
        spin_lock_irqsave(&cmd->t_state_lock, flags);
+       if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req)) {
+               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+               return false;
+       }
+       /*
+        * Only perform a possible wait_for_tasks if SCF_SUPPORTED_SAM_OPCODE
+        * has been set in transport_set_supported_SAM_opcode().
+        */
+       if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) && !cmd->se_tmr_req) {
+               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+               return false;
+       }
        /*
         * If we are already stopped due to an external event (ie: LUN shutdown)
         * sleep until the connection can have the passed struct se_cmd back.
@@ -4666,16 +4260,17 @@ static void transport_generic_wait_for_tasks(
                atomic_set(&cmd->transport_lun_stop, 0);
        }
        if (!atomic_read(&cmd->t_transport_active) ||
-            atomic_read(&cmd->t_transport_aborted))
-               goto remove;
+            atomic_read(&cmd->t_transport_aborted)) {
+               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+               return false;
+       }
 
        atomic_set(&cmd->t_transport_stop, 1);
 
        pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
-               " i_state: %d, t_state/def_t_state: %d/%d, t_transport_stop"
-               " = TRUE\n", cmd, cmd->se_tfo->get_task_tag(cmd),
-               cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
-               cmd->deferred_t_state);
+               " i_state: %d, t_state: %d, t_transport_stop = TRUE\n",
+               cmd, cmd->se_tfo->get_task_tag(cmd),
+               cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
 
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
@@ -4690,13 +4285,12 @@ static void transport_generic_wait_for_tasks(
        pr_debug("wait_for_tasks: Stopped wait_for_compltion("
                "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
                cmd->se_tfo->get_task_tag(cmd));
-remove:
+
        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-       if (!remove_cmd)
-               return;
 
-       transport_generic_free_cmd(cmd, 0, session_reinstatement);
+       return true;
 }
+EXPORT_SYMBOL(transport_wait_for_tasks);
 
 static int transport_get_sense_codes(
        struct se_cmd *cmd,
@@ -4921,6 +4515,15 @@ EXPORT_SYMBOL(transport_check_aborted_status);
 
 void transport_send_task_abort(struct se_cmd *cmd)
 {
+       unsigned long flags;
+
+       spin_lock_irqsave(&cmd->t_state_lock, flags);
+       if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
+               spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+               return;
+       }
+       spin_unlock_irqrestore(&cmd->t_state_lock, flags);
+
        /*
         * If there are still expected incoming fabric WRITEs, we wait
         * until until they have completed before sending a TASK_ABORTED
@@ -4931,9 +4534,6 @@ void transport_send_task_abort(struct se_cmd *cmd)
                if (cmd->se_tfo->write_pending_status(cmd) != 0) {
                        atomic_inc(&cmd->t_transport_aborted);
                        smp_mb__after_atomic_inc();
-                       cmd->scsi_status = SAM_STAT_TASK_ABORTED;
-                       transport_new_cmd_failure(cmd);
-                       return;
                }
        }
        cmd->scsi_status = SAM_STAT_TASK_ABORTED;
@@ -4985,184 +4585,10 @@ int transport_generic_do_tmr(struct se_cmd *cmd)
        cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
        cmd->se_tfo->queue_tm_rsp(cmd);
 
-       transport_cmd_check_stop(cmd, 2, 0);
+       transport_cmd_check_stop_to_fabric(cmd);
        return 0;
 }
 
-/*
- *     Called with spin_lock_irq(&dev->execute_task_lock); held
- *
- */
-static struct se_task *
-transport_get_task_from_state_list(struct se_device *dev)
-{
-       struct se_task *task;
-
-       if (list_empty(&dev->state_task_list))
-               return NULL;
-
-       list_for_each_entry(task, &dev->state_task_list, t_state_list)
-               break;
-
-       list_del(&task->t_state_list);
-       atomic_set(&task->task_state_active, 0);
-
-       return task;
-}
-
-static void transport_processing_shutdown(struct se_device *dev)
-{
-       struct se_cmd *cmd;
-       struct se_task *task;
-       unsigned long flags;
-       /*
-        * Empty the struct se_device's struct se_task state list.
-        */
-       spin_lock_irqsave(&dev->execute_task_lock, flags);
-       while ((task = transport_get_task_from_state_list(dev))) {
-               if (!task->task_se_cmd) {
-                       pr_err("task->task_se_cmd is NULL!\n");
-                       continue;
-               }
-               cmd = task->task_se_cmd;
-
-               spin_unlock_irqrestore(&dev->execute_task_lock, flags);
-
-               spin_lock_irqsave(&cmd->t_state_lock, flags);
-
-               pr_debug("PT: cmd: %p task: %p ITT: 0x%08x,"
-                       " i_state: %d, t_state/def_t_state:"
-                       " %d/%d cdb: 0x%02x\n", cmd, task,
-                       cmd->se_tfo->get_task_tag(cmd),
-                       cmd->se_tfo->get_cmd_state(cmd),
-                       cmd->t_state, cmd->deferred_t_state,
-                       cmd->t_task_cdb[0]);
-               pr_debug("PT: ITT[0x%08x] - t_tasks: %d t_task_cdbs_left:"
-                       " %d t_task_cdbs_sent: %d -- t_transport_active: %d"
-                       " t_transport_stop: %d t_transport_sent: %d\n",
-                       cmd->se_tfo->get_task_tag(cmd),
-                       cmd->t_task_list_num,
-                       atomic_read(&cmd->t_task_cdbs_left),
-                       atomic_read(&cmd->t_task_cdbs_sent),
-                       atomic_read(&cmd->t_transport_active),
-                       atomic_read(&cmd->t_transport_stop),
-                       atomic_read(&cmd->t_transport_sent));
-
-               if (atomic_read(&task->task_active)) {
-                       atomic_set(&task->task_stop, 1);
-                       spin_unlock_irqrestore(
-                               &cmd->t_state_lock, flags);
-
-                       pr_debug("Waiting for task: %p to shutdown for dev:"
-                               " %p\n", task, dev);
-                       wait_for_completion(&task->task_stop_comp);
-                       pr_debug("Completed task: %p shutdown for dev: %p\n",
-                               task, dev);
-
-                       spin_lock_irqsave(&cmd->t_state_lock, flags);
-                       atomic_dec(&cmd->t_task_cdbs_left);
-
-                       atomic_set(&task->task_active, 0);
-                       atomic_set(&task->task_stop, 0);
-               } else {
-                       if (atomic_read(&task->task_execute_queue) != 0)
-                               transport_remove_task_from_execute_queue(task, dev);
-               }
-               __transport_stop_task_timer(task, &flags);
-
-               if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
-                       spin_unlock_irqrestore(
-                                       &cmd->t_state_lock, flags);
-
-                       pr_debug("Skipping task: %p, dev: %p for"
-                               " t_task_cdbs_ex_left: %d\n", task, dev,
-                               atomic_read(&cmd->t_task_cdbs_ex_left));
-
-                       spin_lock_irqsave(&dev->execute_task_lock, flags);
-                       continue;
-               }
-
-               if (atomic_read(&cmd->t_transport_active)) {
-                       pr_debug("got t_transport_active = 1 for task: %p, dev:"
-                                       " %p\n", task, dev);
-
-                       if (atomic_read(&cmd->t_fe_count)) {
-                               spin_unlock_irqrestore(
-                                       &cmd->t_state_lock, flags);
-                               transport_send_check_condition_and_sense(
-                                       cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE,
-                                       0);
-                               transport_remove_cmd_from_queue(cmd,
-                                       &cmd->se_dev->dev_queue_obj);
-
-                               transport_lun_remove_cmd(cmd);
-                               transport_cmd_check_stop(cmd, 1, 0);
-                       } else {
-                               spin_unlock_irqrestore(
-                                       &cmd->t_state_lock, flags);
-
-                               transport_remove_cmd_from_queue(cmd,
-                                       &cmd->se_dev->dev_queue_obj);
-
-                               transport_lun_remove_cmd(cmd);
-
-                               if (transport_cmd_check_stop(cmd, 1, 0))
-                                       transport_generic_remove(cmd, 0);
-                       }
-
-                       spin_lock_irqsave(&dev->execute_task_lock, flags);
-                       continue;
-               }
-               pr_debug("Got t_transport_active = 0 for task: %p, dev: %p\n",
-                               task, dev);
-
-               if (atomic_read(&cmd->t_fe_count)) {
-                       spin_unlock_irqrestore(
-                               &cmd->t_state_lock, flags);
-                       transport_send_check_condition_and_sense(cmd,
-                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
-                       transport_remove_cmd_from_queue(cmd,
-                               &cmd->se_dev->dev_queue_obj);
-
-                       transport_lun_remove_cmd(cmd);
-                       transport_cmd_check_stop(cmd, 1, 0);
-               } else {
-                       spin_unlock_irqrestore(
-                               &cmd->t_state_lock, flags);
-
-                       transport_remove_cmd_from_queue(cmd,
-                               &cmd->se_dev->dev_queue_obj);
-                       transport_lun_remove_cmd(cmd);
-
-                       if (transport_cmd_check_stop(cmd, 1, 0))
-                               transport_generic_remove(cmd, 0);
-               }
-
-               spin_lock_irqsave(&dev->execute_task_lock, flags);
-       }
-       spin_unlock_irqrestore(&dev->execute_task_lock, flags);
-       /*
-        * Empty the struct se_device's struct se_cmd list.
-        */
-       while ((cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj))) {
-
-               pr_debug("From Device Queue: cmd: %p t_state: %d\n",
-                               cmd, cmd->t_state);
-
-               if (atomic_read(&cmd->t_fe_count)) {
-                       transport_send_check_condition_and_sense(cmd,
-                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
-
-                       transport_lun_remove_cmd(cmd);
-                       transport_cmd_check_stop(cmd, 1, 0);
-               } else {
-                       transport_lun_remove_cmd(cmd);
-                       if (transport_cmd_check_stop(cmd, 1, 0))
-                               transport_generic_remove(cmd, 0);
-               }
-       }
-}
-
 /*     transport_processing_thread():
  *
  *
@@ -5173,8 +4599,6 @@ static int transport_processing_thread(void *param)
        struct se_cmd *cmd;
        struct se_device *dev = (struct se_device *) param;
 
-       set_user_nice(current, -20);
-
        while (!kthread_should_stop()) {
                ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq,
                                atomic_read(&dev->dev_queue_obj.queue_cnt) ||
@@ -5182,14 +4606,6 @@ static int transport_processing_thread(void *param)
                if (ret < 0)
                        goto out;
 
-               spin_lock_irq(&dev->dev_status_lock);
-               if (dev->dev_status & TRANSPORT_DEVICE_SHUTDOWN) {
-                       spin_unlock_irq(&dev->dev_status_lock);
-                       transport_processing_shutdown(dev);
-                       continue;
-               }
-               spin_unlock_irq(&dev->dev_status_lock);
-
 get_cmd:
                __transport_execute_tasks(dev);
 
@@ -5198,6 +4614,9 @@ get_cmd:
                        continue;
 
                switch (cmd->t_state) {
+               case TRANSPORT_NEW_CMD:
+                       BUG();
+                       break;
                case TRANSPORT_NEW_CMD_MAP:
                        if (!cmd->se_tfo->new_cmd_map) {
                                pr_err("cmd->se_tfo->new_cmd_map is"
@@ -5206,54 +4625,31 @@ get_cmd:
                        }
                        ret = cmd->se_tfo->new_cmd_map(cmd);
                        if (ret < 0) {
-                               cmd->transport_error_status = ret;
-                               transport_generic_request_failure(cmd, NULL,
-                                               0, (cmd->data_direction !=
-                                                   DMA_TO_DEVICE));
+                               transport_generic_request_failure(cmd);
                                break;
                        }
-                       /* Fall through */
-               case TRANSPORT_NEW_CMD:
                        ret = transport_generic_new_cmd(cmd);
-                       if (ret == -EAGAIN)
+                       if (ret < 0) {
+                               transport_generic_request_failure(cmd);
                                break;
-                       else if (ret < 0) {
-                               cmd->transport_error_status = ret;
-                               transport_generic_request_failure(cmd, NULL,
-                                       0, (cmd->data_direction !=
-                                        DMA_TO_DEVICE));
                        }
                        break;
                case TRANSPORT_PROCESS_WRITE:
                        transport_generic_process_write(cmd);
                        break;
-               case TRANSPORT_COMPLETE_OK:
-                       transport_stop_all_task_timers(cmd);
-                       transport_generic_complete_ok(cmd);
-                       break;
-               case TRANSPORT_REMOVE:
-                       transport_generic_remove(cmd, 0);
-                       break;
-               case TRANSPORT_FREE_CMD_INTR:
-                       transport_generic_free_cmd(cmd, 0, 0);
-                       break;
                case TRANSPORT_PROCESS_TMR:
                        transport_generic_do_tmr(cmd);
                        break;
-               case TRANSPORT_COMPLETE_FAILURE:
-                       transport_generic_request_failure(cmd, NULL, 1, 1);
-                       break;
-               case TRANSPORT_COMPLETE_TIMEOUT:
-                       transport_stop_all_task_timers(cmd);
-                       transport_generic_request_timeout(cmd);
-                       break;
                case TRANSPORT_COMPLETE_QF_WP:
-                       transport_generic_write_pending(cmd);
+                       transport_write_pending_qf(cmd);
+                       break;
+               case TRANSPORT_COMPLETE_QF_OK:
+                       transport_complete_qf(cmd);
                        break;
                default:
-                       pr_err("Unknown t_state: %d deferred_t_state:"
-                               " %d for ITT: 0x%08x i_state: %d on SE LUN:"
-                               " %u\n", cmd->t_state, cmd->deferred_t_state,
+                       pr_err("Unknown t_state: %d  for ITT: 0x%08x "
+                               "i_state: %d on SE LUN: %u\n",
+                               cmd->t_state,
                                cmd->se_tfo->get_task_tag(cmd),
                                cmd->se_tfo->get_cmd_state(cmd),
                                cmd->se_lun->unpacked_lun);
@@ -5264,7 +4660,8 @@ get_cmd:
        }
 
 out:
-       transport_release_all_cmds(dev);
+       WARN_ON(!list_empty(&dev->state_task_list));
+       WARN_ON(!list_empty(&dev->dev_queue_obj.qobj_list));
        dev->process_thread = NULL;
        return 0;
 }