#ifndef _LINUX_HIGHMEM_H #define _LINUX_HIGHMEM_H #include <linux/fs.h> #include <linux/mm.h> #include <linux/uaccess.h> #include <asm/cacheflush.h> #ifndef ARCH_HAS_FLUSH_ANON_PAGE static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr) { } #endif #ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE static inline void flush_kernel_dcache_page(struct page *page) { } #endif #ifdef CONFIG_HIGHMEM #include <asm/highmem.h> /* declarations for linux/mm/highmem.c */ unsigned int nr_free_highpages(void); extern unsigned long totalhigh_pages; void kmap_flush_unused(void); #else /* CONFIG_HIGHMEM */ static inline unsigned int nr_free_highpages(void) { return 0; } #define totalhigh_pages 0 #ifndef ARCH_HAS_KMAP static inline void *kmap(struct page *page) { might_sleep(); return page_address(page); } #define kunmap(page) do { (void) (page); } while (0) #include <asm/kmap_types.h> static inline void *kmap_atomic(struct page *page, enum km_type idx) { pagefault_disable(); return page_address(page); } #define kmap_atomic_prot(page, idx, prot) kmap_atomic(page, idx) #define kunmap_atomic(addr, idx) do { pagefault_enable(); } while (0) #define kmap_atomic_pfn(pfn, idx) kmap_atomic(pfn_to_page(pfn), (idx)) #define kmap_atomic_to_page(ptr) virt_to_page(ptr) #define kmap_flush_unused() do {} while(0) #endif #endif /* CONFIG_HIGHMEM */ /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */ static inline void clear_user_highpage(struct page *page, unsigned long vaddr) { void *addr = kmap_atomic(page, KM_USER0); clear_user_page(addr, vaddr, page); kunmap_atomic(addr, KM_USER0); /* Make sure this page is cleared on other CPU's too before using it */ smp_wmb(); } #ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE /** * __alloc_zeroed_user_highpage - Allocate a zeroed HIGHMEM page for a VMA with caller-specified movable GFP flags * @movableflags: The GFP flags related to the pages future ability to move like __GFP_MOVABLE * @vma: The VMA the page is to be allocated for * @vaddr: The virtual address the page will be inserted into * * This function will allocate a page for a VMA but the caller is expected * to specify via movableflags whether the page will be movable in the * future or not * * An architecture may override this function by defining * __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE and providing their own * implementation. */ static inline struct page * __alloc_zeroed_user_highpage(gfp_t movableflags, struct vm_area_struct *vma, unsigned long vaddr) { struct page *page = alloc_page_vma(GFP_HIGHUSER | movableflags, vma, vaddr); if (page) clear_user_highpage(page, vaddr); return page; } #endif /** * alloc_zeroed_user_highpage_movable - Allocate a zeroed HIGHMEM page for a VMA that the caller knows can move * @vma: The VMA the page is to be allocated for * @vaddr: The virtual address the page will be inserted into * * This function will allocate a page for a VMA that the caller knows will * be able to migrate in the future using move_pages() or reclaimed */ static inline struct page * alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma, unsigned long vaddr) { return __alloc_zeroed_user_highpage(__GFP_MOVABLE, vma, vaddr); } static inline void clear_highpage(struct page *page) { void *kaddr = kmap_atomic(page, KM_USER0); clear_page(kaddr); kunmap_atomic(kaddr, KM_USER0); } /* * Same but also flushes aliased cache contents to RAM. * * This must be a macro because KM_USER0 and friends aren't defined if * !CONFIG_HIGHMEM */ #define zero_user_page(page, offset, size, km_type) \ do { \ void *kaddr; \ \ BUG_ON((offset) + (size) > PAGE_SIZE); \ \ kaddr = kmap_atomic(page, km_type); \ memset((char *)kaddr + (offset), 0, (size)); \ flush_dcache_page(page); \ kunmap_atomic(kaddr, (km_type)); \ } while (0) static inline void __deprecated memclear_highpage_flush(struct page *page, unsigned int offset, unsigned int size) { zero_user_page(page, offset, size, KM_USER0); } #ifndef __HAVE_ARCH_COPY_USER_HIGHPAGE static inline void copy_user_highpage(struct page *to, struct page *from, unsigned long vaddr, struct vm_area_struct *vma) { char *vfrom, *vto; vfrom = kmap_atomic(from, KM_USER0); vto = kmap_atomic(to, KM_USER1); copy_user_page(vto, vfrom, vaddr, to); kunmap_atomic(vfrom, KM_USER0); kunmap_atomic(vto, KM_USER1); /* Make sure this page is cleared on other CPU's too before using it */ smp_wmb(); } #endif static inline void copy_highpage(struct page *to, struct page *from) { char *vfrom, *vto; vfrom = kmap_atomic(from, KM_USER0); vto = kmap_atomic(to, KM_USER1); copy_page(vto, vfrom); kunmap_atomic(vfrom, KM_USER0); kunmap_atomic(vto, KM_USER1); } #endif /* _LINUX_HIGHMEM_H */