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author | Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> | 2009-07-10 16:57:35 (GMT) |
---|---|---|
committer | H. Peter Anvin <hpa@zytor.com> | 2009-08-26 22:41:16 (GMT) |
commit | 9e36fda0b359d2a6ae039c3d7e71a04502a77898 (patch) | |
tree | a1a50780b15cf59de22ee4ee87fee6e488a310d3 /arch | |
parent | 9fd126bc742f74a95d2ba610247712ff05da02fe (diff) | |
download | linux-9e36fda0b359d2a6ae039c3d7e71a04502a77898.tar.xz |
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')
-rw-r--r-- | arch/x86/include/asm/iomap.h | 9 | ||||
-rw-r--r-- | arch/x86/mm/iomap_32.c | 27 |
2 files changed, 31 insertions, 5 deletions
diff --git a/arch/x86/include/asm/iomap.h b/arch/x86/include/asm/iomap.h index 0e9fe1d..f35eb45 100644 --- a/arch/x86/include/asm/iomap.h +++ b/arch/x86/include/asm/iomap.h @@ -26,13 +26,16 @@ #include <asm/pgtable.h> #include <asm/tlbflush.h> -int -is_io_mapping_possible(resource_size_t base, unsigned long size); - void * iomap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot); void iounmap_atomic(void *kvaddr, enum km_type type); +int +iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot); + +void +iomap_free(resource_size_t base, unsigned long size); + #endif /* _ASM_X86_IOMAP_H */ diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c index fe6f84c..84e236c 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) { |