[PATCH 2/5] x86/pci: Add a to_pci_sysdata helper

[Christoph Hellwig]

Various helpers need the pci_sysdata just to dereference a single field
in it.  Add a little helper that returns the properly typed sysdata
pointer to require a little less boilerplate code.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 arch/x86/include/asm/pci.h | 28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index 6fa846920f5f..75fe28492290 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -35,12 +35,15 @@ extern int noioapicreroute;
 
 #ifdef CONFIG_PCI
 
+static inline struct pci_sysdata *to_pci_sysdata(struct pci_bus *bus)
+{
+	return bus->sysdata;
+}
+
 #ifdef CONFIG_PCI_DOMAINS
 static inline int pci_domain_nr(struct pci_bus *bus)
 {
-	struct pci_sysdata *sd = bus->sysdata;
-
-	return sd->domain;
+	return to_pci_sysdata(bus)->domain;
 }
 
 static inline int pci_proc_domain(struct pci_bus *bus)
@@ -52,23 +55,20 @@ static inline int pci_proc_domain(struct pci_bus *bus)
 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
 static inline void *_pci_root_bus_fwnode(struct pci_bus *bus)
 {
-	struct pci_sysdata *sd = bus->sysdata;
-
-	return sd->fwnode;
+	return to_pci_sysdata(bus)->fwnode;
 }
 
 #define pci_root_bus_fwnode	_pci_root_bus_fwnode
 #endif
 
+#if IS_ENABLED(CONFIG_VMD)
 static inline bool is_vmd(struct pci_bus *bus)
 {
-#if IS_ENABLED(CONFIG_VMD)
-	struct pci_sysdata *sd = bus->sysdata;
-
-	return sd->vmd_domain;
+	return to_pci_sysdata(bus)->vmd_domain;
+}
 #else
-	return false;
-#endif
+#define is_vmd(bus)		false
+#endif /* CONFIG_VMD */
 }
 
 /* Can be used to override the logic in pci_scan_bus for skipping
@@ -128,9 +128,7 @@ void native_restore_msi_irqs(struct pci_dev *dev);
 /* Returns the node based on pci bus */
 static inline int __pcibus_to_node(const struct pci_bus *bus)
 {
-	const struct pci_sysdata *sd = bus->sysdata;
-
-	return sd->node;
+	return to_pci_sysdata(bus)->node;
 }
 
 static inline const struct cpumask *
-- 
2.20.1