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>
This commit is contained in:
committed by
H. Peter Anvin
parent
9fd126bc74
commit
9e36fda0b3
@@ -21,7 +21,7 @@
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#include <linux/module.h>
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#include <linux/highmem.h>
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int is_io_mapping_possible(resource_size_t base, unsigned long size)
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static int is_io_mapping_possible(resource_size_t base, unsigned long size)
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{
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#if !defined(CONFIG_X86_PAE) && defined(CONFIG_PHYS_ADDR_T_64BIT)
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/* There is no way to map greater than 1 << 32 address without PAE */
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@@ -30,7 +30,30 @@ int is_io_mapping_possible(resource_size_t base, unsigned long size)
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#endif
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return 1;
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}
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EXPORT_SYMBOL_GPL(is_io_mapping_possible);
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int iomap_create_wc(resource_size_t base, unsigned long size, pgprot_t *prot)
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{
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unsigned long flag = _PAGE_CACHE_WC;
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int ret;
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if (!is_io_mapping_possible(base, size))
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return -EINVAL;
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ret = io_reserve_memtype(base, base + size, &flag);
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if (ret)
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return ret;
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*prot = __pgprot(__PAGE_KERNEL | flag);
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return 0;
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}
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EXPORT_SYMBOL_GPL(iomap_create_wc);
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void
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iomap_free(resource_size_t base, unsigned long size)
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{
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io_free_memtype(base, base + size);
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}
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EXPORT_SYMBOL_GPL(iomap_free);
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void *kmap_atomic_prot_pfn(unsigned long pfn, enum km_type type, pgprot_t prot)
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{
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