From: Sinan Kaya <okaya@codeaurora.org>
Date: Thu, 19 Jul 2018 18:04:12 -0500
Subject: PCI: Unify try slot and bus reset API
Patch-mainline: v4.19-rc1
Git-commit: 811c5cb37df46b0cd714dbd053d19cdb97d08cff
References: bsc#1114685 FATE#325854

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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/hfi1/pcie.c |    2 +-
 drivers/pci/pci.c                 |   21 ++++++++++++++++-----
 drivers/vfio/pci/vfio_pci.c       |    6 ++----
 include/linux/pci.h               |    3 +--
 4 files changed, 20 insertions(+), 12 deletions(-)

--- a/drivers/infiniband/hw/hfi1/pcie.c
+++ b/drivers/infiniband/hw/hfi1/pcie.c
@@ -905,7 +905,7 @@ static int trigger_sbr(struct hfi1_devda
 	 * 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);
 }
 
 /*
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4824,12 +4824,12 @@ 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;
 
@@ -4850,7 +4850,6 @@ int pci_try_reset_slot(struct pci_slot *
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(pci_try_reset_slot);
 
 static int pci_bus_reset(struct pci_bus *bus, int probe)
 {
@@ -4911,12 +4910,12 @@ 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;
 
@@ -4937,6 +4936,18 @@ int pci_try_reset_bus(struct pci_bus *bu
 
 	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);
 
 /**
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -1027,8 +1027,7 @@ 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--)
@@ -1381,8 +1380,7 @@ static void vfio_pci_try_bus_reset(struc
 	}
 
 	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++) {
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1100,10 +1100,9 @@ int pci_reset_function_locked(struct pci
 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);
 int pci_reset_bridge_secondary_bus(struct pci_dev *dev);