[Scst-svn] SF.net SVN: scst:[7923] trunk/scst/src/scst_targ.c

[<bva...@us...>]

Revision: 7923
          http://sourceforge.net/p/scst/svn/7923
Author:   bvassche
Date:     2019-02-12 03:40:48 +0000 (Tue, 12 Feb 2019)
Log Message:
-----------
scst: Introduce scst_handle_aca()

Move the ACA code out of __scst_init_cmd() to make __scst_init_cmd()
easier to read. This patch does not change any functionality.

Modified Paths:
--------------
    trunk/scst/src/scst_targ.c

Modified: trunk/scst/src/scst_targ.c
===================================================================
--- trunk/scst/src/scst_targ.c	2019-02-12 03:16:12 UTC (rev 7922)
+++ trunk/scst/src/scst_targ.c	2019-02-12 03:40:48 UTC (rev 7923)
@@ -5036,6 +5036,89 @@
 	return res;
 }
 
+static void scst_handle_aca(struct scst_cmd *cmd)
+{
+	struct scst_order_data *order_data = cmd->cur_order_data;
+	unsigned long flags;
+
+again:
+	if (unlikely(order_data->aca_tgt_dev != 0)) {
+		spin_lock_irqsave(&order_data->sn_lock, flags);
+		if (order_data->aca_tgt_dev == 0) {
+			spin_unlock_irqrestore(&order_data->sn_lock, flags);
+			goto again;
+		}
+
+		if (order_data->aca_tgt_dev == (unsigned long)cmd->tgt_dev) {
+			if (cmd->queue_type != SCST_CMD_QUEUE_ACA ||
+			    order_data->aca_cmd || cmd->dev->tmf_only) {
+				TRACE_DBG("Refusing cmd %p, because ACA active (aca_cmd %p, tgt_dev %p)",
+					  cmd, order_data->aca_cmd,
+					  cmd->tgt_dev);
+				goto out_unlock_aca_active;
+			} else {
+				TRACE_MGMT_DBG("ACA cmd %p (tgt_dev %p)",
+					       cmd, cmd->tgt_dev);
+				order_data->aca_cmd = cmd;
+				/* allow it */
+			}
+		} else {
+			/* Non-faulted I_T nexus */
+			EXTRACHECKS_BUG_ON(cmd->dev->tst !=
+					   SCST_TST_0_SINGLE_TASK_SET);
+			if (cmd->queue_type == SCST_CMD_QUEUE_ACA) {
+				TRACE_MGMT_DBG("Refusing ACA cmd %p from wrong I_T nexus (aca_tgt_dev %ld, cmd->tgt_dev %p)",
+					       cmd, order_data->aca_tgt_dev,
+					       cmd->tgt_dev);
+				scst_set_cmd_error(cmd,
+					SCST_LOAD_SENSE(scst_sense_invalid_message));
+				goto out_unlock_aca_active;
+			} else {
+				if (cmd->cdb[0] == PERSISTENT_RESERVE_OUT &&
+				    (cmd->cdb[1] & 0x1f) ==
+				    PR_PREEMPT_AND_ABORT) {
+					TRACE_MGMT_DBG("Allow PR PREEMPT AND ABORT cmd %p during ACA (tgt_dev %p)",
+						       cmd, cmd->tgt_dev);
+					/* allow it */
+				} else {
+					TRACE_DBG("Refusing other IT-nexus cmd %p, because ACA active (tgt_dev %p)",
+						  cmd, cmd->tgt_dev);
+					if (cmd->cmd_naca)
+						goto out_unlock_aca_active;
+					else {
+						spin_unlock_irqrestore(&order_data->sn_lock, flags);
+						scst_set_cmd_error_status(cmd, SAM_STAT_BUSY);
+						goto out_bypass_aca;
+					}
+				}
+			}
+		}
+
+		cmd->cmd_aca_allowed = 1;
+
+		spin_unlock_irqrestore(&order_data->sn_lock, flags);
+	} else if (unlikely(cmd->queue_type == SCST_CMD_QUEUE_ACA)) {
+		TRACE_MGMT_DBG("Refusing ACA cmd %p, because there's no ACA, tgt_dev %p",
+			       cmd, cmd->tgt_dev);
+		scst_set_cmd_error(cmd,
+				   SCST_LOAD_SENSE(scst_sense_invalid_message));
+		goto out_abnormal;
+	}
+
+	return;
+
+out_unlock_aca_active:
+	spin_unlock_irqrestore(&order_data->sn_lock, flags);
+	scst_set_cmd_error_status(cmd, SAM_STAT_ACA_ACTIVE);
+
+out_bypass_aca:
+	cmd->cmd_aca_allowed = 1; /* for check in scst_pre_xmit_response2() */
+
+out_abnormal:
+	scst_set_cmd_abnormal_done_state(cmd);
+	return;
+}
+
 /*
  * No locks, but might be on IRQ.
  *
@@ -5045,8 +5128,6 @@
 static int __scst_init_cmd(struct scst_cmd *cmd)
 {
 	int res = 0;
-	unsigned long flags;
-	struct scst_order_data *order_data;
 
 	TRACE_ENTRY();
 
@@ -5055,8 +5136,6 @@
 		int cnt;
 		bool failure = false;
 
-		order_data = cmd->cur_order_data;
-
 		scst_set_cmd_state(cmd, SCST_CMD_STATE_PARSE);
 
 		cnt = atomic_inc_return(&cmd->tgt_dev->tgt_dev_cmd_count);
@@ -5102,74 +5181,10 @@
 		 * queue_type to change it if needed. ToDo.
 		 */
 		scst_pre_parse(cmd);
-again:
-		if (unlikely(order_data->aca_tgt_dev != 0)) {
-			spin_lock_irqsave(&order_data->sn_lock, flags);
+		scst_handle_aca(cmd);
+		if (cmd->completed)
+			goto out;
 
-			if (order_data->aca_tgt_dev == 0) {
-				spin_unlock_irqrestore(&order_data->sn_lock, flags);
-				goto again;
-			}
-
-			if (order_data->aca_tgt_dev == (unsigned long)cmd->tgt_dev) {
-				if ((cmd->queue_type != SCST_CMD_QUEUE_ACA) ||
-				    (order_data->aca_cmd != NULL) ||
-				    cmd->dev->tmf_only) {
-					TRACE_DBG("Refusing cmd %p, because ACA "
-						"active (aca_cmd %p, tgt_dev %p)",
-						cmd, order_data->aca_cmd,
-						cmd->tgt_dev);
-					goto out_unlock_aca_active;
-				} else {
-					TRACE_MGMT_DBG("ACA cmd %p (tgt_dev %p)",
-						cmd, cmd->tgt_dev);
-					order_data->aca_cmd = cmd;
-					/* allow it */
-				}
-			} else {
-				/* Non-faulted I_T nexus */
-				EXTRACHECKS_BUG_ON(cmd->dev->tst != SCST_TST_0_SINGLE_TASK_SET);
-				if (cmd->queue_type == SCST_CMD_QUEUE_ACA) {
-					TRACE_MGMT_DBG("Refusing ACA cmd %p "
-						"from wrong I_T nexus (aca_tgt_dev %ld, "
-						"cmd->tgt_dev %p)", cmd,
-						order_data->aca_tgt_dev, cmd->tgt_dev);
-					scst_set_cmd_error(cmd,
-						SCST_LOAD_SENSE(scst_sense_invalid_message));
-					goto out_unlock_aca_active;
-				} else {
-					if ((cmd->cdb[0] == PERSISTENT_RESERVE_OUT) &&
-					    ((cmd->cdb[1] & 0x1f) == PR_PREEMPT_AND_ABORT)) {
-						TRACE_MGMT_DBG("Allow PR PREEMPT AND "
-							"ABORT cmd %p during ACA "
-							"(tgt_dev %p)", cmd, cmd->tgt_dev);
-						/* allow it */
-					} else {
-						TRACE_DBG("Refusing other IT-nexus "
-							"cmd %p, because ACA active "
-							"(tgt_dev %p)", cmd, cmd->tgt_dev);
-						if (cmd->cmd_naca)
-							goto out_unlock_aca_active;
-						else {
-							spin_unlock_irqrestore(&order_data->sn_lock, flags);
-							scst_set_cmd_error_status(cmd, SAM_STAT_BUSY);
-							goto out_bypass_aca;
-						}
-					}
-				}
-			}
-
-			cmd->cmd_aca_allowed = 1;
-
-			spin_unlock_irqrestore(&order_data->sn_lock, flags);
-		} else if (unlikely(cmd->queue_type == SCST_CMD_QUEUE_ACA)) {
-			TRACE_MGMT_DBG("Refusing ACA cmd %p, because there's no ACA, "
-				"tgt_dev %p", cmd, cmd->tgt_dev);
-			scst_set_cmd_error(cmd,
-				SCST_LOAD_SENSE(scst_sense_invalid_message));
-			goto out_abnormal;
-		}
-
 		if (!cmd->set_sn_on_restart_cmd) {
 			if (!cmd->tgtt->multithreaded_init_done)
 				scst_cmd_set_sn(cmd);
@@ -5194,18 +5209,11 @@
 
 out_busy_bypass_aca:
 	scst_set_busy(cmd);
-
-out_bypass_aca:
 	cmd->cmd_aca_allowed = 1; /* for check in scst_pre_xmit_response2() */
 
 out_abnormal:
 	scst_set_cmd_abnormal_done_state(cmd);
 	goto out;
-
-out_unlock_aca_active:
-	spin_unlock_irqrestore(&order_data->sn_lock, flags);
-	scst_set_cmd_error_status(cmd, SAM_STAT_ACA_ACTIVE);
-	goto out_bypass_aca;
 }
 
 /* Called under scst_init_lock and IRQs disabled */

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