[Linux1394-cvslog] rev 768 - trunk

[SVN U. <ben...@li...>]

Author: bencollins
Date: 2003-02-04 23:41:18 -0500 (Tue, 04 Feb 2003)
New Revision: 768

Modified:
   trunk/sbp2.c
Log:
Patch from Sancho Dauskard  fixing sbp2 SMP lockups.


Modified: trunk/sbp2.c
==============================================================================
--- trunk/sbp2.c	(original)
+++ trunk/sbp2.c	2003-02-04 23:41:19.000000000 -0500
@@ -296,6 +296,9 @@
  *		   returns the dead bit in status. Thanks to Chandan (ch...@to...) for this one.
  *	04/27/02 - Fix sbp2 login problem on SMP systems, enable real spinlocks by default. (JSG)
  *	06/09/02 - Don't force 36-bute SCSI inquiry, but leave in a define for badly behaved devices. (JSG)   
+ *	02/04/03 - Fixed a SMP deadlock (don't hold sbp2_command_lock while calling sbp2scsi_complete_command).
+ *		   Also save/restore irq flags in sbp2scsi_complete_command  - Sancho Dauskardt <sd...@bd...>
+ *
  */
 
 
@@ -2605,13 +2608,6 @@
 			}
 
 			SBP2_ORB_DEBUG("completing command orb %p", &command->command_orb);
-
-			/*
-			 * Complete the SCSI command
-			 */
-			SBP2_DEBUG("Completing SCSI command");
-			sbp2scsi_complete_command(hi, scsi_id, scsi_status, SCpnt, command->Current_done);
-			SBP2_ORB_DEBUG("command orb completed");
 		}
 
 		/*
@@ -2636,6 +2632,22 @@
 	}
 
 	sbp2_spin_unlock(&hi->sbp2_command_lock, flags);
+
+
+	if (SCpnt) {
+
+		/*
+		 * Complete the SCSI command.
+		 *
+		 * Only do it after we've released the sbp2_command_lock,
+		 * as it might otherwise deadlock with the 
+		 * io_request_lock (in sbp2scsi_queuecommand).
+		 */
+		SBP2_DEBUG("Completing SCSI command");
+		sbp2scsi_complete_command(hi, scsi_id, scsi_status, SCpnt, command->Current_done);
+		SBP2_ORB_DEBUG("command orb completed");
+	}
+
 	return(RCODE_COMPLETE);
 }
 
@@ -2761,10 +2773,14 @@
 
 /*
  * This function is called in order to complete a regular SBP-2 command.
+ *
+ * This can be called in interrupt context.
  */
 static void sbp2scsi_complete_command(struct sbp2scsi_host_info *hi, struct scsi_id_instance_data *scsi_id, u32 scsi_status,
 				      Scsi_Cmnd *SCpnt, void (*done)(Scsi_Cmnd *))
 {
+	unsigned long flags;
+
 	SBP2_DEBUG("sbp2scsi_complete_command");
 
 	/*
@@ -2864,13 +2880,13 @@
 	 * Tell scsi stack that we're done with this command
 	 */
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
-	spin_lock_irq(&io_request_lock);
+	spin_lock_irqsave(&io_request_lock,flags);
 	done (SCpnt);
-	spin_unlock_irq(&io_request_lock);
+	spin_unlock_irqrestore(&io_request_lock,flags);
 #else
-	spin_lock_irq(hi->scsi_host->host_lock);
+	spin_lock_irqsave(hi->scsi_host->host_lock,flags);
 	done (SCpnt);
-	spin_unlock_irq(hi->scsi_host->host_lock);
+	spin_unlock_irqrestore(hi->scsi_host->host_lock,flags);
 #endif
 
 	return;