diff options
| author | Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | 2009-07-10 09:57:35 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@zytor.com> | 2009-08-26 15:41:16 -0700 |
| commit | 9e36fda0b359d2a6ae039c3d7e71a04502a77898 (patch) | |
| tree | a1a50780b15cf59de22ee4ee87fee6e488a310d3 /arch/x86/mm | |
| parent | 9fd126bc742f74a95d2ba610247712ff05da02fe (diff) | |
x86, pat: Add PAT reserve free to io_mapping* APIs
io_mapping_* interfaces were added, mainly for graphics drivers.
Make this interface go through the PAT reserve/free, instead of
hardcoding WC mapping. This makes sure that there are no
aliases due to unconditional WC setting.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/iomap_32.c | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c index fe6f84ca121..84e236ce76b 100644 --- a/arch/x86/mm/iomap_32.c +++ b/arch/x86/mm/iomap_32.c @@ -21,7 +21,7 @@ #include <linux/module.h> #include <linux/highmem.h> -int is_io_mapping_possible(resource_size_t base, unsigned long size) +static int is_io_mapping_possible(resource_size_t base, unsigned long size) { #if !defined(CONFIG_X86_PAE) && defined(CONFIG_PHYS_ADDR_T_64BIT) /* There is no way to map greater than 1 << 32 address without PAE */ @@ -30,7 +30,30 @@ int is_io_mapping_possible(resource_size_t base, unsigned long size) #endif return 1; } -EXPORT_SYMBOL_GPL(is_io_mapping_possible); + +int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot) +{ + unsigned long flag = _PAGE_CACHE_WC; + int ret; + + if (!is_io_mapping_possible(base, size)) + return -EINVAL; + + ret = io_reserve_memtype(base, base + size, &flag); + if (ret) + return ret; + + *prot = __pgprot(__PAGE_KERNEL | flag); + return 0; +} +EXPORT_SYMBOL_GPL(iomap_create_wc); + +void +iomap_free(resource_size_t base, unsigned long size) +{ + io_free_memtype(base, base + size); +} +EXPORT_SYMBOL_GPL(iomap_free); void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot) { |