1 files changed, 26 insertions, 12 deletions

diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
index 0aab85a5155..53df39a22c8 100644
--- a/drivers/pci/xen-pcifront.c
+++ b/drivers/pci/xen-pcifront.c
@@ -20,6 +20,7 @@
 #include <linux/workqueue.h>
 #include <linux/bitops.h>
 #include <linux/time.h>
+#include <xen/platform_pci.h>
 
 #include <asm/xen/swiotlb-xen.h>
 #define INVALID_GRANT_REF (0)
@@ -412,7 +413,7 @@ static int pcifront_claim_resource(struct pci_dev *dev, void *data)
 	return 0;
 }
 
-static int __devinit pcifront_scan_bus(struct pcifront_device *pdev,
+static int pcifront_scan_bus(struct pcifront_device *pdev,
 				unsigned int domain, unsigned int bus,
 				struct pci_bus *b)
 {
@@ -441,7 +442,7 @@ static int __devinit pcifront_scan_bus(struct pcifront_device *pdev,
 	return 0;
 }
 
-static int __devinit pcifront_scan_root(struct pcifront_device *pdev,
+static int pcifront_scan_root(struct pcifront_device *pdev,
 				 unsigned int domain, unsigned int bus)
 {
 	struct pci_bus *b;
@@ -471,12 +472,15 @@ static int __devinit pcifront_scan_root(struct pcifront_device *pdev,
 	}
 	pcifront_init_sd(sd, domain, bus, pdev);
 
+	pci_lock_rescan_remove();
+
 	b = pci_scan_bus_parented(&pdev->xdev->dev, bus,
 				  &pcifront_bus_ops, sd);
 	if (!b) {
 		dev_err(&pdev->xdev->dev,
 			"Error creating PCI Frontend Bus!\n");
 		err = -ENOMEM;
+		pci_unlock_rescan_remove();
 		goto err_out;
 	}
 
@@ -494,6 +498,7 @@ static int __devinit pcifront_scan_root(struct pcifront_device *pdev,
 	/* Create SysFS and notify udev of the devices. Aka: "going live" */
 	pci_bus_add_devices(b);
 
+	pci_unlock_rescan_remove();
 	return err;
 
 err_out:
@@ -503,7 +508,7 @@ err_out:
 	return err;
 }
 
-static int __devinit pcifront_rescan_root(struct pcifront_device *pdev,
+static int pcifront_rescan_root(struct pcifront_device *pdev,
 				   unsigned int domain, unsigned int bus)
 {
 	int err;
@@ -556,6 +561,7 @@ static void pcifront_free_roots(struct pcifront_device *pdev)
 
 	dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
 
+	pci_lock_rescan_remove();
 	list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
 		list_del(&bus_entry->list);
 
@@ -568,6 +574,7 @@ static void pcifront_free_roots(struct pcifront_device *pdev)
 
 		kfree(bus_entry);
 	}
+	pci_unlock_rescan_remove();
 }
 
 static pci_ers_result_t pcifront_common_process(int cmd,
@@ -655,9 +662,9 @@ static void pcifront_do_aer(struct work_struct *data)
 	notify_remote_via_evtchn(pdev->evtchn);
 
 	/*in case of we lost an aer request in four lines time_window*/
-	smp_mb__before_clear_bit();
+	smp_mb__before_atomic();
 	clear_bit(_PDEVB_op_active, &pdev->flags);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 
 	schedule_pcifront_aer_op(pdev);
 
@@ -678,10 +685,9 @@ static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
 	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");
+	} else
 		err = -EEXIST;
-	}
+
 	spin_unlock(&pcifront_dev_lock);
 
 	if (!err && !swiotlb_nr_tbl()) {
@@ -834,7 +840,7 @@ out:
 	return err;
 }
 
-static int __devinit pcifront_try_connect(struct pcifront_device *pdev)
+static int pcifront_try_connect(struct pcifront_device *pdev)
 {
 	int err = -EFAULT;
 	int i, num_roots, len;
@@ -848,7 +854,7 @@ static int __devinit pcifront_try_connect(struct pcifront_device *pdev)
 		goto out;
 
 	err = pcifront_connect_and_init_dma(pdev);
-	if (err) {
+	if (err && err != -EEXIST) {
 		xenbus_dev_fatal(pdev->xdev, err,
 				 "Error setting up PCI Frontend");
 		goto out;
@@ -924,7 +930,7 @@ out:
 	return err;
 }
 
-static int __devinit pcifront_attach_devices(struct pcifront_device *pdev)
+static int pcifront_attach_devices(struct pcifront_device *pdev)
 {
 	int err = -EFAULT;
 	int i, num_roots, len;
@@ -1044,8 +1050,10 @@ static int pcifront_detach_devices(struct pcifront_device *pdev)
 				domain, bus, slot, func);
 			continue;
 		}
+		pci_lock_rescan_remove();
 		pci_stop_and_remove_bus_device(pci_dev);
 		pci_dev_put(pci_dev);
+		pci_unlock_rescan_remove();
 
 		dev_dbg(&pdev->xdev->dev,
 			"PCI device %04x:%02x:%02x.%d removed.\n",
@@ -1068,13 +1076,16 @@ static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
 	case XenbusStateInitialising:
 	case XenbusStateInitWait:
 	case XenbusStateInitialised:
-	case XenbusStateClosed:
 		break;
 
 	case XenbusStateConnected:
 		pcifront_try_connect(pdev);
 		break;
 
+	case XenbusStateClosed:
+		if (xdev->state == XenbusStateClosed)
+			break;
+		/* Missed the backend's CLOSING state -- fallthrough */
 	case XenbusStateClosing:
 		dev_warn(&xdev->dev, "backend going away!\n");
 		pcifront_try_disconnect(pdev);
@@ -1136,6 +1147,9 @@ static int __init pcifront_init(void)
 	if (!xen_pv_domain() || xen_initial_domain())
 		return -ENODEV;
 
+	if (!xen_has_pv_devices())
+		return -ENODEV;
+
 	pci_frontend_registrar(1 /* enable */);
 
 	return xenbus_register_frontend(&xenpci_driver);