[net-next-2.6.git] / include / linux / highmem.h

#ifndef _LINUX_HIGHMEM_H
#define _LINUX_HIGHMEM_H

#include <linux/fs.h>
#include <linux/mm.h>

#include <asm/cacheflush.h>

#ifndef ARCH_HAS_FLUSH_ANON_PAGE
static inline void flush_anon_page(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;

#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)

#define kmap_atomic(page, idx)		page_address(page)
#define kunmap_atomic(addr, idx)	do { } while (0)
#define kmap_atomic_pfn(pfn, idx)	page_address(pfn_to_page(pfn))
#define kmap_atomic_to_page(ptr)	virt_to_page(ptr)
#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
static inline struct page *
alloc_zeroed_user_highpage(struct vm_area_struct *vma, unsigned long vaddr)
{
	struct page *page = alloc_page_vma(GFP_HIGHUSER, vma, vaddr);

	if (page)
		clear_user_highpage(page, vaddr);

	return page;
}
#endif

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.
 */
static inline void memclear_highpage_flush(struct page *page, unsigned int offset, unsigned int size)
{
	void *kaddr;

	BUG_ON(offset + size > PAGE_SIZE);

	kaddr = kmap_atomic(page, KM_USER0);
	memset((char *)kaddr + offset, 0, size);
	flush_dcache_page(page);
	kunmap_atomic(kaddr, KM_USER0);
}

static inline void copy_user_highpage(struct page *to, struct page *from, unsigned long vaddr)
{
	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();
}

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 */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_HIGHMEM_H
	2	#define _LINUX_HIGHMEM_H
	3
1da177e4 LT	4	#include <linux/fs.h>
	5	#include <linux/mm.h>
	6
	7	#include <asm/cacheflush.h>
	8
03beb076 JB	9	#ifndef ARCH_HAS_FLUSH_ANON_PAGE
	10	static inline void flush_anon_page(struct page *page, unsigned long vmaddr)
	11	{
	12	}
	13	#endif
	14
5a3a5a98 JB	15	#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
	16	static inline void flush_kernel_dcache_page(struct page *page)
	17	{
	18	}
	19	#endif
	20
1da177e4 LT	21	#ifdef CONFIG_HIGHMEM
	22
	23	#include <asm/highmem.h>
	24
	25	/* declarations for linux/mm/highmem.c */
	26	unsigned int nr_free_highpages(void);
c1f60a5a	27	extern unsigned long totalhigh_pages;
1da177e4 LT	28
	29	#else /* CONFIG_HIGHMEM */
	30
	31	static inline unsigned int nr_free_highpages(void) { return 0; }
	32
c1f60a5a CL	33	#define totalhigh_pages 0
c1f60a5a CL	34
a6ca1b99	35	#ifndef ARCH_HAS_KMAP
1da177e4 LT	36	static inline void kmap(struct page page)
	37	{
	38	might_sleep();
	39	return page_address(page);
	40	}
	41
	42	#define kunmap(page) do { (void) (page); } while (0)
	43
	44	#define kmap_atomic(page, idx) page_address(page)
	45	#define kunmap_atomic(addr, idx) do { } while (0)
60e64d46	46	#define kmap_atomic_pfn(pfn, idx) page_address(pfn_to_page(pfn))
1da177e4	47	#define kmap_atomic_to_page(ptr) virt_to_page(ptr)
a6ca1b99	48	#endif
1da177e4 LT	49
	50	#endif /* CONFIG_HIGHMEM */
	51
	52	/* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
	53	static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
	54	{
	55	void *addr = kmap_atomic(page, KM_USER0);
	56	clear_user_page(addr, vaddr, page);
	57	kunmap_atomic(addr, KM_USER0);
	58	/* Make sure this page is cleared on other CPU's too before using it */
	59	smp_wmb();
	60	}
	61
	62	#ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
	63	static inline struct page *
	64	alloc_zeroed_user_highpage(struct vm_area_struct *vma, unsigned long vaddr)
	65	{
	66	struct page *page = alloc_page_vma(GFP_HIGHUSER, vma, vaddr);
	67
	68	if (page)
	69	clear_user_highpage(page, vaddr);
	70
	71	return page;
	72	}
	73	#endif
	74
	75	static inline void clear_highpage(struct page *page)
	76	{
	77	void *kaddr = kmap_atomic(page, KM_USER0);
	78	clear_page(kaddr);
	79	kunmap_atomic(kaddr, KM_USER0);
	80	}
	81
	82	/*
	83	* Same but also flushes aliased cache contents to RAM.
	84	*/
	85	static inline void memclear_highpage_flush(struct page *page, unsigned int offset, unsigned int size)
	86	{
	87	void *kaddr;
	88
	89	BUG_ON(offset + size > PAGE_SIZE);
	90
	91	kaddr = kmap_atomic(page, KM_USER0);
	92	memset((char *)kaddr + offset, 0, size);
	93	flush_dcache_page(page);
	94	kunmap_atomic(kaddr, KM_USER0);
	95	}
	96
	97	static inline void copy_user_highpage(struct page to, struct page from, unsigned long vaddr)
	98	{
	99	char vfrom, vto;
	100
	101	vfrom = kmap_atomic(from, KM_USER0);
	102	vto = kmap_atomic(to, KM_USER1);
	103	copy_user_page(vto, vfrom, vaddr, to);
	104	kunmap_atomic(vfrom, KM_USER0);
	105	kunmap_atomic(vto, KM_USER1);
	106	/* Make sure this page is cleared on other CPU's too before using it */
	107	smp_wmb();
	108	}
	109
	110	static inline void copy_highpage(struct page to, struct page from)
	111	{
	112	char vfrom, vto;
113
114	vfrom = kmap_atomic(from, KM_USER0);
115	vto = kmap_atomic(to, KM_USER1);
116	copy_page(vto, vfrom);
117	kunmap_atomic(vfrom, KM_USER0);
118	kunmap_atomic(vto, KM_USER1);
119	}
120
121	#endif /* _LINUX_HIGHMEM_H */