PCI: Unify try slot and bus reset API

Drivers are expected to call pci_try_reset_slot() or pci_try_reset_bus() by
querying if a system supports hotplug or not.  A survey showed that most
drivers don't do this and we are leaking hotplug capability to the user.

Hide pci_try_slot_reset() from drivers and embed into pci_try_bus_reset().
Change pci_try_reset_bus() parameter from struct pci_bus to struct pci_dev.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/infiniband/hw/hfi1/pcie.c

@@ -905,7 +905,7 @@ static int trigger_sbr(struct hfi1_devdata *dd)
 	 * delay after a reset is required.  Per spec requirements,
 	 * the link is either working or not after that point.
 	 */
-	return pci_try_reset_bus(dev->bus);
+	return pci_try_reset_bus(dev);
 }
 
 /*

drivers/pci/pci.c

@@ -4817,12 +4817,12 @@ int pci_reset_slot(struct pci_slot *slot)
 EXPORT_SYMBOL_GPL(pci_reset_slot);
 
 /**
- * pci_try_reset_slot - Try to reset a PCI slot
+ * __pci_try_reset_slot - Try to reset a PCI slot
  * @slot: PCI slot to reset
  *
  * Same as above except return -EAGAIN if the slot cannot be locked
  */
-int pci_try_reset_slot(struct pci_slot *slot)
+static int __pci_try_reset_slot(struct pci_slot *slot)
 {
 	int rc;
 
@@ -4843,7 +4843,6 @@ int pci_try_reset_slot(struct pci_slot *slot)
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(pci_try_reset_slot);
 
 static int pci_bus_reset(struct pci_bus *bus, int probe)
 {
@@ -4906,12 +4905,12 @@ int pci_reset_bus(struct pci_bus *bus)
 EXPORT_SYMBOL_GPL(pci_reset_bus);
 
 /**
- * pci_try_reset_bus - Try to reset a PCI bus
+ * __pci_try_reset_bus - Try to reset a PCI bus
  * @bus: top level PCI bus to reset
  *
  * Same as above except return -EAGAIN if the bus cannot be locked
  */
-int pci_try_reset_bus(struct pci_bus *bus)
+static int __pci_try_reset_bus(struct pci_bus *bus)
 {
 	int rc;
 
@@ -4932,6 +4931,18 @@ int pci_try_reset_bus(struct pci_bus *bus)
 
 	return rc;
 }
+
+/**
+ * pci_try_reset_bus - Try to reset a PCI bus
+ * @pdev: top level PCI device to reset via slot/bus
+ *
+ * Same as above except return -EAGAIN if the bus cannot be locked
+ */
+int pci_try_reset_bus(struct pci_dev *pdev)
+{
+	return pci_probe_reset_slot(pdev->slot) ?
+	    __pci_try_reset_slot(pdev->slot) : __pci_try_reset_bus(pdev->bus);
+}
 EXPORT_SYMBOL_GPL(pci_try_reset_bus);
 
 /**

drivers/vfio/pci/vfio_pci.c

@@ -1010,8 +1010,7 @@ reset_info_exit:
 						    &info, slot);
 		if (!ret)
 			/* User has access, do the reset */
-			ret = slot ? pci_try_reset_slot(vdev->pdev->slot) :
-				     pci_try_reset_bus(vdev->pdev->bus);
+			ret = pci_try_reset_bus(vdev->pdev);
 
 hot_reset_release:
 		for (i--; i >= 0; i--)
@@ -1373,8 +1372,7 @@ static void vfio_pci_try_bus_reset(struct vfio_pci_device *vdev)
 	}
 
 	if (needs_reset)
-		ret = slot ? pci_try_reset_slot(vdev->pdev->slot) :
-			     pci_try_reset_bus(vdev->pdev->bus);
+		ret = pci_try_reset_bus(vdev->pdev);
 
 put_devs:
 	for (i = 0; i < devs.cur_index; i++) {

include/linux/pci.h

@@ -1097,10 +1097,9 @@ int pci_reset_function_locked(struct pci_dev *dev);
 int pci_try_reset_function(struct pci_dev *dev);
 int pci_probe_reset_slot(struct pci_slot *slot);
 int pci_reset_slot(struct pci_slot *slot);
-int pci_try_reset_slot(struct pci_slot *slot);
 int pci_probe_reset_bus(struct pci_bus *bus);
 int pci_reset_bus(struct pci_bus *bus);
-int pci_try_reset_bus(struct pci_bus *bus);
+int pci_try_reset_bus(struct pci_dev *dev);
 void pci_reset_secondary_bus(struct pci_dev *dev);
 void pcibios_reset_secondary_bus(struct pci_dev *dev);
 void pci_update_resource(struct pci_dev *dev, int resno);