mm/pat/memtype.c

3  * Page Attribute Table (PAT) support: handle memory caching attributes in page tables.
24  * PAT doesn't work via explicit memory ranges, but uses page table entries to add
54 #include <asm/page.h>
107  * X86 PAT uses page flags arch_1 and uncached together to keep track of
108  * memory type of pages that have backing page struct.
126 static inline enum page_cache_mode get_page_memtype(struct page *pg)
140 static inline void set_page_memtype(struct page *pg,
169 static inline enum page_cache_mode get_page_memtype(struct page *pg)
173 static inline void set_page_memtype(struct page *pg,
441  * For RAM pages, we use page flags to mark the pages with appropriate type.
442  * The page flags are limited to four types, WB (default), WC, WT and UC-.
444  * a new memory type is only allowed for a page mapped with the default WB
455 	struct page *page;
473 		page = pfn_to_page(pfn);
474 		type = get_page_memtype(page);
489 		page = pfn_to_page(pfn);
490 		set_page_memtype(page, req_type);
497 	struct page *page;
501 		page = pfn_to_page(pfn);
502 		set_page_memtype(page, _PAGE_CACHE_MODE_WB);
558 		/* This is identical to page table setting without PAT */
564 	/* Low ISA region is always mapped WB in page table. No need to track */
679 		struct page *page;
681 		page = pfn_to_page(paddr >> PAGE_SHIFT);
682 		return get_page_memtype(page);
885 	 * the type requested matches the type of first page in the range.
984 	 * information from the page tables. For COW mappings, we might now
1121  * its pfnmap page table has been removed.  The new vma has a new pfnmap