[SCSI] aacraid: fib context lock for management ioctls

Alan noticed the lack of locking surrounding the driver's dealings
with the fib context managed by the trio of ioctls that are used by
the RAID management applications to retrieve Adapter Initiated FIBs. I
merely expanded the fib lock to include the fib context. There have
been no field reports of any issues generally because the applications
are relatively static and do not come and go often enough to stress
this area. I bloated this patch a little with some space junk.
Signed-off-by: NMark Salyzyn <aacraid@adaptec.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/aacraid/commctrl.c

@@ -243,6 +243,7 @@ static int next_getadapter_fib(struct aac_dev * dev, void __user *arg)
 	 *	Search the list of AdapterFibContext addresses on the adapter
 	 *	to be sure this is a valid address
 	 */
+	spin_lock_irqsave(&dev->fib_lock, flags);
 	entry = dev->fib_list.next;
 	fibctx = NULL;
 
@@ -258,17 +259,18 @@ static int next_getadapter_fib(struct aac_dev * dev, void __user *arg)
 		fibctx = NULL;
 	}
 	if (!fibctx) {
+		spin_unlock_irqrestore(&dev->fib_lock, flags);
 		dprintk ((KERN_INFO "Fib Context not found\n"));
 		return -EINVAL;
 	}
 
 	if((fibctx->type != FSAFS_NTC_GET_ADAPTER_FIB_CONTEXT) ||
 		 (fibctx->size != sizeof(struct aac_fib_context))) {
+		spin_unlock_irqrestore(&dev->fib_lock, flags);
 		dprintk ((KERN_INFO "Fib Context corrupt?\n"));
 		return -EINVAL;
 	}
 	status = 0;
-	spin_lock_irqsave(&dev->fib_lock, flags);
 	/*
 	 *	If there are no fibs to send back, then either wait or return
 	 *	-EAGAIN
@@ -326,7 +328,9 @@ static int next_getadapter_fib(struct aac_dev * dev, void __user *arg)
 int aac_close_fib_context(struct aac_dev * dev, struct aac_fib_context * fibctx)
 {
 	struct fib *fib;
+	unsigned long flags;
 
+	spin_lock_irqsave(&dev->fib_lock, flags);
 	/*
 	 *	First free any FIBs that have not been consumed.
 	 */
@@ -349,6 +353,7 @@ int aac_close_fib_context(struct aac_dev * dev, struct aac_fib_context * fibctx)
 	 *	Remove the Context from the AdapterFibContext List
 	 */
 	list_del(&fibctx->next);
+	spin_unlock_irqrestore(&dev->fib_lock, flags);
 	/*
 	 *	Invalidate context
 	 */