Merge branch 'pci/reset'

- Update slot handling so all ARI functions are treated as being in the
  same slot.  They're all reset by Secondary Bus Reset, but previously
  drivers of ARI functions that appeared to be on a non-zero device weren't
  notified and fatal hardware errors could result (Keith Busch)

- Make sysfs reset_subordinate hotplug safe to avoid spurious hotplug
  events (Keith Busch)

- Consolidate bus iteration across the _lock(), _unlock(), and _trylock()
  functions for pci_bus and pci_slot (Ilpo Järvinen)

- Hide Secondary Bus Reset ('bus') from sysfs reset_methods if masked by
  CXL because it has no effect (Vidya Sagar)

* pci/reset:
  PCI/CXL: Hide SBR from reset_methods if masked by CXL
  PCI: Consolidate pci_bus/slot_lock/unlock/trylock()
  PCI: Make reset_subordinate hotplug safe
  PCI: Allow all bus devices to use the same slot
  PCI: Rename __pci_bus_reset() and __pci_slot_reset()

1 files changed, 9 insertions, 1 deletions

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 47c5b0c09ffb..cc98713e3ce8 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -72,12 +72,20 @@
 /* return bus from PCI devid = ((u16)bus_number) << 8) | devfn */
 #define PCI_BUS_NUM(x) (((x) >> 8) & 0xff)
 
+/*
+ * PCI_SLOT_ALL_DEVICES indicates a slot that covers all devices on the bus.
+ * Used for PCIe hotplug where the physical slot is the entire secondary bus,
+ * and, if ARI Forwarding is enabled, functions may appear to be on multiple
+ * devices.
+ */
+#define PCI_SLOT_ALL_DEVICES	0xfe
+
 /* pci_slot represents a physical slot */
 struct pci_slot {
 	struct pci_bus		*bus;		/* Bus this slot is on */
 	struct list_head	list;		/* Node in list of slots */
 	struct hotplug_slot	*hotplug;	/* Hotplug info (move here) */
-	unsigned char		number;		/* PCI_SLOT(pci_dev->devfn) */
+	unsigned char		number;		/* Device nr, or PCI_SLOT_ALL_DEVICES */
 	struct kobject		kobj;
 };