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authorVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>2008-07-10 10:09:59 +0200
committerIngo Molnar <mingo@elte.hu>2008-07-10 10:09:59 +0200
commita361ee5cb8011763ece7b4add393e206439db8b3 (patch)
treeedcde856f84bd4ac87ca381db3c61af9564a5e12 /arch/x86/mm/ioremap.c
parenta1716d508abf77e4bd02c275ab9293b9866929f3 (diff)
x86: fix /dev/mem compatibility under PAT
Add ioremap_default(), which gives a sane mapping without worrying about type conflicts. Use it in /dev/mem read in place of ioremap(), as with ioremap(), any mapping of the region (other than UC_MINUS) will cause a conflict and failure of /dev/mem read. Should address the vbetest failure reported at: http://bugzilla.kernel.org/show_bug.cgi?id=11057 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/mm/ioremap.c')
-rw-r--r--arch/x86/mm/ioremap.c25
1 files changed, 24 insertions, 1 deletions
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 2b2bb3f9b68..d1b867101e5 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -300,6 +300,29 @@ void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
}
EXPORT_SYMBOL(ioremap_cache);
+static void __iomem *ioremap_default(resource_size_t phys_addr,
+ unsigned long size)
+{
+ unsigned long flags;
+ void *ret;
+ int err;
+
+ /*
+ * - WB for WB-able memory and no other conflicting mappings
+ * - UC_MINUS for non-WB-able memory with no other conflicting mappings
+ * - Inherit from confliting mappings otherwise
+ */
+ err = reserve_memtype(phys_addr, phys_addr + size, -1, &flags);
+ if (err < 0)
+ return NULL;
+
+ ret = (void *) __ioremap_caller(phys_addr, size, flags,
+ __builtin_return_address(0));
+
+ free_memtype(phys_addr, phys_addr + size);
+ return (void __iomem *)ret;
+}
+
/**
* iounmap - Free a IO remapping
* @addr: virtual address from ioremap_*
@@ -365,7 +388,7 @@ void *xlate_dev_mem_ptr(unsigned long phys)
if (page_is_ram(start >> PAGE_SHIFT))
return __va(phys);
- addr = (void *)ioremap(start, PAGE_SIZE);
+ addr = (void *)ioremap_default(start, PAGE_SIZE);
if (addr)
addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK));