PCI: X86: Introduce and enable PCI domain support

* fix bug in pci_read() and pci_write() which prevented PCI domain
  support from working (hardcoded domain 0).

* unconditionally enable CONFIG_PCI_DOMAINS

* implement pci_domain_nr() and pci_proc_domain(), as required of
  all arches when CONFIG_PCI_DOMAINS is enabled.

* store domain in struct pci_sysdata, as assigned by ACPI

* support "pci=nodomains"

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 24 insertions, 0 deletions

diff --git a/include/asm-x86/pci_32.h b/include/asm-x86/pci_32.h
index 4fcacc711385..0d91605cd1e2 100644
--- a/include/asm-x86/pci_32.h
+++ b/include/asm-x86/pci_32.h
@@ -5,12 +5,24 @@
 #ifdef __KERNEL__
 
 struct pci_sysdata {
+        int             domain;         /* PCI domain */
         int             node;           /* NUMA node */
 };
 
 /* scan a bus after allocating a pci_sysdata for it */
 extern struct pci_bus *pci_scan_bus_with_sysdata(int busno);
 
+static inline int pci_domain_nr(struct pci_bus *bus)
+{
+        struct pci_sysdata *sd = bus->sysdata;
+        return sd->domain;
+}
+
+static inline int pci_proc_domain(struct pci_bus *bus)
+{
+        return pci_domain_nr(bus);
+}
+
 #include <linux/mm.h>           /* for struct page */
 
 /* Can be used to override the logic in pci_scan_bus for skipping
diff --git a/include/asm-x86/pci_64.h b/include/asm-x86/pci_64.h
index 5da8cb0c0599..0a123d6a820f 100644
--- a/include/asm-x86/pci_64.h
+++ b/include/asm-x86/pci_64.h
@@ -6,12 +6,24 @@
 #ifdef __KERNEL__
 
 struct pci_sysdata {
+        int             domain;         /* PCI domain */
         int             node;           /* NUMA node */
         void*           iommu;          /* IOMMU private data */
 };
 
 extern struct pci_bus *pci_scan_bus_with_sysdata(int busno);
 
+static inline int pci_domain_nr(struct pci_bus *bus)
+{
+        struct pci_sysdata *sd = bus->sysdata;
+        return sd->domain;
+}
+
+static inline int pci_proc_domain(struct pci_bus *bus)
+{
+        return pci_domain_nr(bus);
+}
+
 #ifdef CONFIG_CALGARY_IOMMU
 static inline void* pci_iommu(struct pci_bus *bus)
 {