[PATCH 06/10] x86/PCI: Enable scanning of all pci functions

[Jeremy Fitzhardinge <jeremy@goop.org>]

From: Alex Nixon <alex.nixon@citrix.com>

Xen may want to enable scanning of all pci functions - if for example
the device at function 0 is not passed through to the guest, but the
device at function 1 is.

Jesse objected to the "#undef pcibios_scan_all_fns"'s ugliness,
so replace it with the more common HAVE_ARCH_ idiom.

[ Impact: allow passthrough of just some PCI functions. ]

Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: "H. Peter Anvin" <hpa@zytor.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 arch/x86/include/asm/pci.h |    8 +++++++-
 arch/x86/pci/common.c      |    1 +
 include/asm-generic/pci.h  |    2 ++
 3 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index b51a1e8..cabea93 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -21,6 +21,7 @@ struct pci_sysdata {
 extern int pci_routeirq;
 extern int noioapicquirk;
 extern int noioapicreroute;
+extern int pci_scan_all_fns;
 
 /* scan a bus after allocating a pci_sysdata for it */
 extern struct pci_bus *pci_scan_bus_on_node(int busno, struct pci_ops *ops,
@@ -48,7 +49,11 @@ extern unsigned int pcibios_assign_all_busses(void);
 #else
 #define pcibios_assign_all_busses()	0
 #endif
-#define pcibios_scan_all_fns(a, b)	0
+
+static inline int pcibios_scan_all_fns(struct pci_bus *bus, int devfn)
+{
+	return pci_scan_all_fns;
+}
 
 extern unsigned long pci_mem_start;
 #define PCIBIOS_MIN_IO		0x1000
@@ -129,6 +134,7 @@ extern void pci_iommu_alloc(void);
 #include <asm-generic/pci-dma-compat.h>
 
 /* generic pci stuff */
+#define HAVE_ARCH_PCIBIOS_SCAN_ALL_FNS
 #include <asm-generic/pci.h>
 
 #ifdef CONFIG_NUMA
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 011ff45..6a522c2 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -22,6 +22,7 @@ unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
 unsigned int pci_early_dump_regs;
 static int pci_bf_sort;
 int pci_routeirq;
+int pci_scan_all_fns;
 int noioapicquirk;
 #ifdef CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 int noioapicreroute = 0;
diff --git a/include/asm-generic/pci.h b/include/asm-generic/pci.h
index c36a77d..9ad9cb7 100644
--- a/include/asm-generic/pci.h
+++ b/include/asm-generic/pci.h
@@ -43,7 +43,9 @@ pcibios_select_root(struct pci_dev *pdev, struct resource *res)
 	return root;
 }
 
+#ifndef HAVE_ARCH_PCIBIOS_SCAN_ALL_FNS
 #define pcibios_scan_all_fns(a, b)	0
+#endif
 
 #ifndef HAVE_ARCH_PCI_GET_LEGACY_IDE_IRQ
 static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
-- 
1.6.0.6