Merge tag 'pci-v4.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

[linux-2.6-block.git] / drivers / pci / host / vmd.c

diff --git a/drivers/pci/host/vmd.c b/drivers/pci/host/vmd.c
index ca99fb4f729204d50598b07464cb360ea3bf078a..37e29b580be323a10c9cb17985bd2684873e9bcf 100644 (file)
--- a/drivers/pci/host/vmd.c
+++ b/drivers/pci/host/vmd.c
@@ -41,6 +41,7 @@ static DEFINE_RAW_SPINLOCK(list_lock);
  * @node:      list item for parent traversal.
  * @rcu:       RCU callback item for freeing.
  * @irq:       back pointer to parent.
+ * @enabled:   true if driver enabled IRQ
  * @virq:      the virtual IRQ value provided to the requesting driver.
  *
  * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
@@ -50,6 +51,7 @@ struct vmd_irq {
        struct list_head        node;
        struct rcu_head         rcu;
        struct vmd_irq_list     *irq;
+       bool                    enabled;
        unsigned int            virq;
 };
 
@@ -124,7 +126,9 @@ static void vmd_irq_enable(struct irq_data *data)
        unsigned long flags;
 
        raw_spin_lock_irqsave(&list_lock, flags);
+       WARN_ON(vmdirq->enabled);
        list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
+       vmdirq->enabled = true;
        raw_spin_unlock_irqrestore(&list_lock, flags);
 
        data->chip->irq_unmask(data);
@@ -138,8 +142,10 @@ static void vmd_irq_disable(struct irq_data *data)
        data->chip->irq_mask(data);
 
        raw_spin_lock_irqsave(&list_lock, flags);
-       list_del_rcu(&vmdirq->node);
-       INIT_LIST_HEAD_RCU(&vmdirq->node);
+       if (vmdirq->enabled) {
+               list_del_rcu(&vmdirq->node);
+               vmdirq->enabled = false;
+       }
        raw_spin_unlock_irqrestore(&list_lock, flags);
 }