This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / xen / pcifront / pci.c

diff --git a/drivers/xen/pcifront/pci.c b/drivers/xen/pcifront/pci.c
new file mode 100644 (file)
index 0000000..4239f00
--- /dev/null
+++ b/drivers/xen/pcifront/pci.c
@@ -0,0 +1,46 @@
+/*
+ * PCI Frontend Operations - ensure only one PCI frontend runs at a time
+ *
+ *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include "pcifront.h"
+
+DEFINE_SPINLOCK(pcifront_dev_lock);
+static struct pcifront_device *pcifront_dev = NULL;
+
+int pcifront_connect(struct pcifront_device *pdev)
+{
+       int err = 0;
+
+       spin_lock(&pcifront_dev_lock);
+
+       if (!pcifront_dev) {
+               dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
+               pcifront_dev = pdev;
+       }
+       else {
+               dev_err(&pdev->xdev->dev, "PCI frontend already installed!\n");
+               err = -EEXIST;
+       }
+
+       spin_unlock(&pcifront_dev_lock);
+
+       return err;
+}
+
+void pcifront_disconnect(struct pcifront_device *pdev)
+{
+       spin_lock(&pcifront_dev_lock);
+
+       if (pdev == pcifront_dev) {
+               dev_info(&pdev->xdev->dev,
+                        "Disconnecting PCI Frontend Buses\n");
+               pcifront_dev = NULL;
+       }
+
+       spin_unlock(&pcifront_dev_lock);
+}