1 files changed, 116 insertions, 109 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index c648bd328a21..a9d7e520e551 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -109,7 +109,7 @@ iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
                  * if the window closed with IO queued, then kick the
                  * xmit thread
                  */
-                if (!list_empty(&session->leadconn->xmitqueue) ||
+                if (!list_empty(&session->leadconn->cmdqueue) ||
                     !list_empty(&session->leadconn->mgmtqueue)) {
                         if (!(session->tt->caps & CAP_DATA_PATH_OFFLOAD))
                                 iscsi_conn_queue_work(session->leadconn);
@@ -366,7 +366,6 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
                 return -EIO;
 
         task->state = ISCSI_TASK_RUNNING;
-        list_move_tail(&task->running, &conn->run_list);
 
         conn->scsicmd_pdus_cnt++;
         ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
@@ -382,26 +381,23 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 }
 
 /**
- * iscsi_complete_command - finish a task
+ * iscsi_free_task - free a task
  * @task: iscsi cmd task
  *
  * Must be called with session lock.
  * This function returns the scsi command to scsi-ml or cleans
  * up mgmt tasks then returns the task to the pool.
  */
-static void iscsi_complete_command(struct iscsi_task *task)
+static void iscsi_free_task(struct iscsi_task *task)
 {
         struct iscsi_conn *conn = task->conn;
         struct iscsi_session *session = conn->session;
         struct scsi_cmnd *sc = task->sc;
 
         session->tt->cleanup_task(task);
-        list_del_init(&task->running);
-        task->state = ISCSI_TASK_COMPLETED;
+        task->state = ISCSI_TASK_FREE;
         task->sc = NULL;
 
-        if (conn->task == task)
-                conn->task = NULL;
         /*
          * login task is preallocated so do not free
          */
@@ -410,9 +406,6 @@ static void iscsi_complete_command(struct iscsi_task *task)
 
         __kfifo_put(session->cmdpool.queue, (void*)&task, sizeof(void*));
 
-        if (conn->ping_task == task)
-                conn->ping_task = NULL;
-
         if (sc) {
                 task->sc = NULL;
                 /* SCSI eh reuses commands to verify us */
@@ -435,7 +428,7 @@ EXPORT_SYMBOL_GPL(__iscsi_get_task);
 static void __iscsi_put_task(struct iscsi_task *task)
 {
         if (atomic_dec_and_test(&task->refcount))
-                iscsi_complete_command(task);
+                iscsi_free_task(task);
 }
 
 void iscsi_put_task(struct iscsi_task *task)
@@ -448,14 +441,50 @@ void iscsi_put_task(struct iscsi_task *task)
 }
 EXPORT_SYMBOL_GPL(iscsi_put_task);
 
+/**
+ * iscsi_complete_task - finish a task
+ * @task: iscsi cmd task
+ *
+ * Must be called with session lock.
+ */
+static void iscsi_complete_task(struct iscsi_task *task)
+{
+        struct iscsi_conn *conn = task->conn;
+
+        if (task->state == ISCSI_TASK_COMPLETED)
+                return;
+        WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
+
+        task->state = ISCSI_TASK_COMPLETED;
+
+        if (!list_empty(&task->running))
+                list_del_init(&task->running);
+
+        if (conn->task == task)
+                conn->task = NULL;
+
+        if (conn->ping_task == task)
+                conn->ping_task = NULL;
+
+        /* release get from queueing */
+        __iscsi_put_task(task);
+}
+
 /*
- * session lock must be held
+ * session lock must be held and if not called for a task that is
+ * still pending or from the xmit thread, then xmit thread must
+ * be suspended.
  */
-static void fail_command(struct iscsi_conn *conn, struct iscsi_task *task,
-                         int err)
+static void fail_scsi_task(struct iscsi_task *task, int err)
 {
+        struct iscsi_conn *conn = task->conn;
         struct scsi_cmnd *sc;
 
+        /*
+         * if a command completes and we get a successful tmf response
+         * we will hit this because the scsi eh abort code does not take
+         * a ref to the task.
+         */
         sc = task->sc;
         if (!sc)
                 return;
@@ -475,10 +504,7 @@ static void fail_command(struct iscsi_conn *conn, struct iscsi_task *task,
                 scsi_in(sc)->resid = scsi_in(sc)->length;
         }
 
-        if (conn->task == task)
-                conn->task = NULL;
-        /* release ref from queuecommand */
-        __iscsi_put_task(task);
+        iscsi_complete_task(task);
 }
 
 static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
@@ -518,7 +544,6 @@ static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
                 session->state = ISCSI_STATE_LOGGING_OUT;
 
         task->state = ISCSI_TASK_RUNNING;
-        list_move_tail(&task->running, &conn->mgmt_run_list);
         ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
                           "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
                           hdr->itt, task->data_count);
@@ -564,6 +589,8 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
         atomic_set(&task->refcount, 1);
         task->conn = conn;
         task->sc = NULL;
+        INIT_LIST_HEAD(&task->running);
+        task->state = ISCSI_TASK_PENDING;
 
         if (data_size) {
                 memcpy(task->data, data, data_size);
@@ -575,7 +602,7 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
                         iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
                                          "pdu for mgmt task.\n");
-                        goto requeue_task;
+                        goto free_task;
                 }
         }
 
@@ -591,30 +618,22 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                                                    task->conn->session->age);
         }
 
-        INIT_LIST_HEAD(&task->running);
-        list_add_tail(&task->running, &conn->mgmtqueue);
-
         if (session->tt->caps & CAP_DATA_PATH_OFFLOAD) {
                 if (iscsi_prep_mgmt_task(conn, task))
                         goto free_task;
 
                 if (session->tt->xmit_task(task))
                         goto free_task;
-
-        } else
+        } else {
+                list_add_tail(&task->running, &conn->mgmtqueue);
                 iscsi_conn_queue_work(conn);
+        }
 
         return task;
 
 free_task:
         __iscsi_put_task(task);
         return NULL;
-
-requeue_task:
-        if (task != conn->login_task)
-                __kfifo_put(session->cmdpool.queue, (void*)&task,
-                            sizeof(void*));
-        return NULL;
 }
 
 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
@@ -709,11 +728,10 @@ invalid_datalen:
                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
         }
 out:
-        ISCSI_DBG_SESSION(session, "done [sc %p res %d itt 0x%x]\n",
+        ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
                           sc, sc->result, task->itt);
         conn->scsirsp_pdus_cnt++;
-
-        __iscsi_put_task(task);
+        iscsi_complete_task(task);
 }
 
 /**
@@ -747,8 +765,11 @@ iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                         sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
         }
 
+        ISCSI_DBG_SESSION(conn->session, "data in with status done "
+                          "[sc %p res %d itt 0x%x]\n",
+                          sc, sc->result, task->itt);
         conn->scsirsp_pdus_cnt++;
-        __iscsi_put_task(task);
+        iscsi_complete_task(task);
 }
 
 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
@@ -969,7 +990,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                 }
 
                 iscsi_tmf_rsp(conn, hdr);
-                __iscsi_put_task(task);
+                iscsi_complete_task(task);
                 break;
         case ISCSI_OP_NOOP_IN:
                 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
@@ -987,7 +1008,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
                         goto recv_pdu;
 
                 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
-                __iscsi_put_task(task);
+                iscsi_complete_task(task);
                 break;
         default:
                 rc = ISCSI_ERR_BAD_OPCODE;
@@ -999,7 +1020,7 @@ out:
 recv_pdu:
         if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
                 rc = ISCSI_ERR_CONN_FAILED;
-        __iscsi_put_task(task);
+        iscsi_complete_task(task);
         return rc;
 }
 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
@@ -1176,7 +1197,12 @@ void iscsi_requeue_task(struct iscsi_task *task)
 {
         struct iscsi_conn *conn = task->conn;
 
-        list_move_tail(&task->running, &conn->requeue);
+        /*
+         * this may be on the requeue list already if the xmit_task callout
+         * is handling the r2ts while we are adding new ones
+         */
+        if (list_empty(&task->running))
+                list_add_tail(&task->running, &conn->requeue);
         iscsi_conn_queue_work(conn);
 }
 EXPORT_SYMBOL_GPL(iscsi_requeue_task);
@@ -1216,6 +1242,7 @@ check_mgmt:
         while (!list_empty(&conn->mgmtqueue)) {
                 conn->task = list_entry(conn->mgmtqueue.next,
                                          struct iscsi_task, running);
+                list_del_init(&conn->task->running);
                 if (iscsi_prep_mgmt_task(conn, conn->task)) {
                         __iscsi_put_task(conn->task);
                         conn->task = NULL;
@@ -1227,23 +1254,26 @@ check_mgmt:
         }
 
         /* process pending command queue */
-        while (!list_empty(&conn->xmitqueue)) {
+        while (!list_empty(&conn->cmdqueue)) {
                 if (conn->tmf_state == TMF_QUEUED)
                         break;
 
-                conn->task = list_entry(conn->xmitqueue.next,
+                conn->task = list_entry(conn->cmdqueue.next,
                                          struct iscsi_task, running);
+                list_del_init(&conn->task->running);
                 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
-                        fail_command(conn, conn->task, DID_IMM_RETRY << 16);
+                        fail_scsi_task(conn->task, DID_IMM_RETRY << 16);
                         continue;
                 }
                 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
                 if (rc) {
                         if (rc == -ENOMEM) {
+                                list_add_tail(&conn->task->running,
+                                              &conn->cmdqueue);
                                 conn->task = NULL;
                                 goto again;
                         } else
-                                fail_command(conn, conn->task, DID_ABORT << 16);
+                                fail_scsi_task(conn->task, DID_ABORT << 16);
                         continue;
                 }
                 rc = iscsi_xmit_task(conn);
@@ -1270,8 +1300,8 @@ check_mgmt:
 
                 conn->task = list_entry(conn->requeue.next,
                                          struct iscsi_task, running);
+                list_del_init(&conn->task->running);
                 conn->task->state = ISCSI_TASK_RUNNING;
-                list_move_tail(conn->requeue.next, &conn->run_list);
                 rc = iscsi_xmit_task(conn);
                 if (rc)
                         goto again;
@@ -1412,7 +1442,6 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
                 reason = FAILURE_OOM;
                 goto reject;
         }
-        list_add_tail(&task->running, &conn->xmitqueue);
 
         if (session->tt->caps & CAP_DATA_PATH_OFFLOAD) {
                 reason = iscsi_prep_scsi_cmd_pdu(task);
@@ -1429,8 +1458,10 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
                         reason = FAILURE_SESSION_NOT_READY;
                         goto prepd_reject;
                 }
-        } else
+        } else {
+                list_add_tail(&task->running, &conn->cmdqueue);
                 iscsi_conn_queue_work(conn);
+        }
 
         session->queued_cmdsn++;
         spin_unlock(&session->lock);
@@ -1439,7 +1470,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 
 prepd_reject:
         sc->scsi_done = NULL;
-        iscsi_complete_command(task);
+        iscsi_complete_task(task);
 reject:
         spin_unlock(&session->lock);
         ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
@@ -1449,7 +1480,7 @@ reject:
 
 prepd_fault:
         sc->scsi_done = NULL;
-        iscsi_complete_command(task);
+        iscsi_complete_task(task);
 fault:
         spin_unlock(&session->lock);
         ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
@@ -1618,44 +1649,24 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
  * Fail commands. session lock held and recv side suspended and xmit
  * thread flushed
  */
-static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
-                              int error)
+static void fail_scsi_tasks(struct iscsi_conn *conn, unsigned lun,
+                            int error)
 {
-        struct iscsi_task *task, *tmp;
-
-        if (conn->task) {
-                if (lun == -1 ||
-                    (conn->task->sc && conn->task->sc->device->lun == lun))
-                        conn->task = NULL;
-        }
+        struct iscsi_task *task;
+        int i;
 
-        /* flush pending */
-        list_for_each_entry_safe(task, tmp, &conn->xmitqueue, running) {
-                if (lun == task->sc->device->lun || lun == -1) {
-                        ISCSI_DBG_SESSION(conn->session,
-                                          "failing pending sc %p itt 0x%x\n",
-                                          task->sc, task->itt);
-                        fail_command(conn, task, error << 16);
-                }
-        }
+        for (i = 0; i < conn->session->cmds_max; i++) {
+                task = conn->session->cmds[i];
+                if (!task->sc || task->state == ISCSI_TASK_FREE)
+                        continue;
 
-        list_for_each_entry_safe(task, tmp, &conn->requeue, running) {
-                if (lun == task->sc->device->lun || lun == -1) {
-                        ISCSI_DBG_SESSION(conn->session,
-                                          "failing requeued sc %p itt 0x%x\n",
-                                          task->sc, task->itt);
-                        fail_command(conn, task, error << 16);
-                }
-        }
+                if (lun != -1 && lun != task->sc->device->lun)
+                        continue;
 
-        /* fail all other running */
-        list_for_each_entry_safe(task, tmp, &conn->run_list, running) {
-                if (lun == task->sc->device->lun || lun == -1) {
-                        ISCSI_DBG_SESSION(conn->session,
-                                         "failing in progress sc %p itt 0x%x\n",
-                                         task->sc, task->itt);
-                        fail_command(conn, task, error << 16);
-                }
+                ISCSI_DBG_SESSION(conn->session,
+                                  "failing sc %p itt 0x%x state %d\n",
+                                  task->sc, task->itt, task->state);
+                fail_scsi_task(task, error << 16);
         }
 }
 
@@ -1859,7 +1870,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
         }
 
         if (task->state == ISCSI_TASK_PENDING) {
-                fail_command(conn, task, DID_ABORT << 16);
+                fail_scsi_task(task, DID_ABORT << 16);
                 goto success;
         }
 
@@ -1890,7 +1901,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
                  * then sent more data for the cmd.
                  */
                 spin_lock(&session->lock);
-                fail_command(conn, task, DID_ABORT << 16);
+                fail_scsi_task(task, DID_ABORT << 16);
                 conn->tmf_state = TMF_INITIAL;
                 spin_unlock(&session->lock);
                 iscsi_start_tx(conn);
@@ -1997,7 +2008,7 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
         iscsi_suspend_tx(conn);
 
         spin_lock_bh(&session->lock);
-        fail_all_commands(conn, sc->device->lun, DID_ERROR);
+        fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
         conn->tmf_state = TMF_INITIAL;
         spin_unlock_bh(&session->lock);
 
@@ -2304,6 +2315,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
                 if (cmd_task_size)
                         task->dd_data = &task[1];
                 task->itt = cmd_i;
+                task->state = ISCSI_TASK_FREE;
                 INIT_LIST_HEAD(&task->running);
         }
 
@@ -2390,10 +2402,8 @@ iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
         conn->transport_timer.data = (unsigned long)conn;
         conn->transport_timer.function = iscsi_check_transport_timeouts;
 
-        INIT_LIST_HEAD(&conn->run_list);
-        INIT_LIST_HEAD(&conn->mgmt_run_list);
         INIT_LIST_HEAD(&conn->mgmtqueue);
-        INIT_LIST_HEAD(&conn->xmitqueue);
+        INIT_LIST_HEAD(&conn->cmdqueue);
         INIT_LIST_HEAD(&conn->requeue);
         INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
 
@@ -2561,27 +2571,24 @@ int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
 EXPORT_SYMBOL_GPL(iscsi_conn_start);
 
 static void
-flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
+fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
 {
-        struct iscsi_task *task, *tmp;
+        struct iscsi_task *task;
+        int i;
 
-        /* handle pending */
-        list_for_each_entry_safe(task, tmp, &conn->mgmtqueue, running) {
-                ISCSI_DBG_SESSION(session, "flushing pending mgmt task "
-                                  "itt 0x%x\n", task->itt);
-                /* release ref from prep task */
-                __iscsi_put_task(task);
-        }
+        for (i = 0; i < conn->session->cmds_max; i++) {
+                task = conn->session->cmds[i];
+                if (task->sc)
+                        continue;
 
-        /* handle running */
-        list_for_each_entry_safe(task, tmp, &conn->mgmt_run_list, running) {
-                ISCSI_DBG_SESSION(session, "flushing running mgmt task "
-                                  "itt 0x%x\n", task->itt);
-                /* release ref from prep task */
-                __iscsi_put_task(task);
-        }
+                if (task->state == ISCSI_TASK_FREE)
+                        continue;
 
-        conn->task = NULL;
+                ISCSI_DBG_SESSION(conn->session,
+                                  "failing mgmt itt 0x%x state %d\n",
+                                  task->itt, task->state);
+                iscsi_complete_task(task);
+        }
 }
 
 static void iscsi_start_session_recovery(struct iscsi_session *session,
@@ -2638,10 +2645,10 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
          */
         spin_lock_bh(&session->lock);
         if (flag == STOP_CONN_RECOVER)
-                fail_all_commands(conn, -1, DID_TRANSPORT_DISRUPTED);
+                fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
         else
-                fail_all_commands(conn, -1, DID_ERROR);
-        flush_control_queues(session, conn);
+                fail_scsi_tasks(conn, -1, DID_ERROR);
+        fail_mgmt_tasks(session, conn);
         spin_unlock_bh(&session->lock);
         mutex_unlock(&session->eh_mutex);
 }