From dc4adbf41385486b0c73e7382ce73f0e8b873243 Mon Sep 17 00:00:00 2001
From: Mark Haverkamp <markh@osdl.org>
Date: Mon, 27 Mar 2006 09:44:26 -0800
Subject: [PATCH] [SCSI] aacraid: Re-start helper thread if it dies

Received from Mark Salyzyn

Since the helper thread for the driver can be killed unceremoniously by
an application, we detect the loss of the helper and restart it.

Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
---
 drivers/scsi/aacraid/commctrl.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/scsi/aacraid/commctrl.c b/drivers/scsi/aacraid/commctrl.c
index 47fefca72695..9f75144e5247 100644
--- a/drivers/scsi/aacraid/commctrl.c
+++ b/drivers/scsi/aacraid/commctrl.c
@@ -38,6 +38,8 @@
 #include <linux/completion.h>
 #include <linux/dma-mapping.h>
 #include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
 #include <asm/semaphore.h>
 #include <asm/uaccess.h>
 
@@ -293,6 +295,16 @@ static int next_getadapter_fib(struct aac_dev * dev, void __user *arg)
 		status = 0;
 	} else {
 		spin_unlock_irqrestore(&dev->fib_lock, flags);
+		/* If someone killed the AIF aacraid thread, restart it */
+		status = !dev->aif_thread;
+		if (status && dev->queues && dev->fsa_dev) {
+			/* Be paranoid, be very paranoid! */
+			kthread_stop(dev->thread);
+			ssleep(1);
+			dev->aif_thread = 0;
+			dev->thread = kthread_run(aac_command_thread, dev, dev->name);
+			ssleep(1);
+		}
 		if (f.wait) {
 			if(down_interruptible(&fibctx->wait_sem) < 0) {
 				status = -EINTR;