I/OAT: fix I/OAT for kexec

Under kexec, I/OAT initialization breaks over busy resources because the
previous kernel did not release them.

I'm not sure this fix can be considered a complete one but it works for me.
 I guess something similar to the *_remove method should occur there..

Signed-off-by: Dan Aloni <da-x@monatomic.org>
Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drivers/dma/ioatdma.c

@@ -41,6 +41,7 @@
 
 /* internal functions */
 static int __devinit ioat_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
+static void ioat_shutdown(struct pci_dev *pdev);
 static void __devexit ioat_remove(struct pci_dev *pdev);
 
 static int enumerate_dma_channels(struct ioat_device *device)
@@ -557,6 +558,7 @@ static struct pci_driver ioat_pci_driver = {
 	.name 	= "ioatdma",
 	.id_table = ioat_pci_tbl,
 	.probe	= ioat_probe,
+	.shutdown = ioat_shutdown,
 	.remove	= __devexit_p(ioat_remove),
 };
 
@@ -781,9 +783,20 @@ err_request_regions:
 err_set_dma_mask:
 	pci_disable_device(pdev);
 err_enable_device:
+
+	printk(KERN_ERR "Intel(R) I/OAT DMA Engine initialization failed\n");
+
 	return err;
 }
 
+static void ioat_shutdown(struct pci_dev *pdev)
+{
+	struct ioat_device *device;
+	device = pci_get_drvdata(pdev);
+
+	dma_async_device_unregister(&device->common);
+}
+
 static void __devexit ioat_remove(struct pci_dev *pdev)
 {
 	struct ioat_device *device;