[PATCH 08/10] x86/pci: make sure _PAGE_IOMAP it set on pci mappings

Jeremy Fitzhardinge
2009-05-13T03:09:05Z

From: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

When mapping pci space via /sys or /proc, make sure we're really
doing a hardware mapping by setting _PAGE_IOMAP.

[ Impact: bugfix; make PCI mappings map the right pages ]
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>
---
arch/x86/pci/i386.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index a85bef2..88a1080 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -278,6 +278,9 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
return -EINVAL;

prot = pgprot_val(vma->vm_page_prot);
+
+ prot |= _PAGE_IOMAP; /* creating a mapping for IO */
+
if (pat_enabled && write_combine)
prot |= _PAGE_CACHE_WC;
else if (pat_enabled || boot_cpu_data.x86 > 3)
--
1.6.0.6