[RFC 01/12] PCI: Add helpers to identify SR-IOV PFs/VFs.

[Dimitri Daskalakis <dimitri.daskalakis1@gmail.com>]

From: Dimitri Daskalakis <daskald@meta.com>

Throughout core the pci_dev attribute is_physfn is used to determine
whether or not a PF has SR-IOV active. And is_virtfn is used to check
if a device is a SR-IOV VF.

These attributes should be generalized to represent PFs/VFs for any type
of virtualization. So in preparation, wrap the existing usage in
helpers and use helpers in subsequent patches to ease the transition.

Assisted-by: Claude:claude-opus-4.7
Signed-off-by: Dimitri Daskalakis <daskald@meta.com>
---
 include/linux/pci.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 2c4454583c11..28892243f49f 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -604,6 +604,16 @@ static inline struct pci_dev *pci_physfn(struct pci_dev *dev)
 	return dev;
 }
 
+static inline bool pci_is_sriov_physfn(const struct pci_dev *dev)
+{
+	return dev->is_physfn;
+}
+
+static inline bool pci_is_sriov_virtfn(const struct pci_dev *dev)
+{
+	return dev->is_virtfn;
+}
+
 struct pci_dev *pci_alloc_dev(struct pci_bus *bus);
 
 #define	to_pci_dev(n) container_of(n, struct pci_dev, dev)
@@ -1277,6 +1287,7 @@ void pcibios_setup_bridge(struct pci_bus *bus, unsigned long type);
 void pci_sort_breadthfirst(void);
 #define dev_is_pci(d) ((d)->bus == &pci_bus_type)
 #define dev_is_pf(d) ((dev_is_pci(d) ? to_pci_dev(d)->is_physfn : false))
+#define dev_is_sriov_pf(d) ((dev_is_pci(d) ? pci_is_sriov_physfn(to_pci_dev(d)) : false))
 
 /* Generic PCI functions exported to card drivers */
 
@@ -2207,6 +2218,7 @@ static inline struct pci_dev *pci_dev_get(struct pci_dev *dev) { return NULL; }
 
 #define dev_is_pci(d) (false)
 #define dev_is_pf(d) (false)
+#define dev_is_sriov_pf(d) (false)
 static inline bool pci_acs_enabled(struct pci_dev *pdev, u16 acs_flags)
 { return false; }
 static inline int pci_irqd_intx_xlate(struct irq_domain *d,
-- 
2.52.0