136 lines
3.0 KiB
C
136 lines
3.0 KiB
C
#ifndef _LINUX_HIGHMEM_H
|
|
#define _LINUX_HIGHMEM_H
|
|
|
|
#include <linux/config.h>
|
|
#include <asm/pgalloc.h>
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
|
|
extern struct page *highmem_start_page;
|
|
|
|
#include <asm/highmem.h>
|
|
|
|
/* declarations for linux/mm/highmem.c */
|
|
unsigned int nr_free_highpages(void);
|
|
|
|
extern struct buffer_head *create_bounce(int rw, struct buffer_head * bh_orig);
|
|
|
|
static inline char *bh_kmap(struct buffer_head *bh)
|
|
{
|
|
return kmap(bh->b_page) + bh_offset(bh);
|
|
}
|
|
|
|
static inline void bh_kunmap(struct buffer_head *bh)
|
|
{
|
|
kunmap(bh->b_page);
|
|
}
|
|
|
|
/*
|
|
* remember to add offset! and never ever reenable interrupts between a
|
|
* bh_kmap_irq and bh_kunmap_irq!!
|
|
*/
|
|
static inline char *bh_kmap_irq(struct buffer_head *bh, unsigned long *flags)
|
|
{
|
|
unsigned long addr;
|
|
|
|
__save_flags(*flags);
|
|
|
|
/*
|
|
* could be low
|
|
*/
|
|
if (!PageHighMem(bh->b_page))
|
|
return bh->b_data;
|
|
|
|
/*
|
|
* it's a highmem page
|
|
*/
|
|
__cli();
|
|
addr = (unsigned long) kmap_atomic(bh->b_page, KM_BH_IRQ);
|
|
|
|
if (addr & ~PAGE_MASK)
|
|
BUG();
|
|
|
|
return (char *) addr + bh_offset(bh);
|
|
}
|
|
|
|
static inline void bh_kunmap_irq(char *buffer, unsigned long *flags)
|
|
{
|
|
unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
|
|
|
|
kunmap_atomic((void *) ptr, KM_BH_IRQ);
|
|
__restore_flags(*flags);
|
|
}
|
|
|
|
#else /* CONFIG_HIGHMEM */
|
|
|
|
static inline unsigned int nr_free_highpages(void) { return 0; }
|
|
|
|
static inline void *kmap(struct page *page) { return page_address(page); }
|
|
|
|
#define kunmap(page) do { } while (0)
|
|
|
|
#define kmap_atomic(page,idx) kmap(page)
|
|
#define kunmap_atomic(page,idx) kunmap(page)
|
|
|
|
#define bh_kmap(bh) ((bh)->b_data)
|
|
#define bh_kunmap(bh) do { } while (0)
|
|
#define kmap_nonblock(page) kmap(page)
|
|
#define bh_kmap_irq(bh, flags) ((bh)->b_data)
|
|
#define bh_kunmap_irq(bh, flags) do { *(flags) = 0; } while (0)
|
|
|
|
#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);
|
|
kunmap_atomic(addr, KM_USER0);
|
|
}
|
|
|
|
static inline void clear_highpage(struct page *page)
|
|
{
|
|
clear_page(kmap(page));
|
|
kunmap(page);
|
|
}
|
|
|
|
/*
|
|
* Same but also flushes aliased cache contents to RAM.
|
|
*/
|
|
static inline void memclear_highpage_flush(struct page *page, unsigned int offset, unsigned int size)
|
|
{
|
|
char *kaddr;
|
|
|
|
if (offset + size > PAGE_SIZE)
|
|
out_of_line_bug();
|
|
kaddr = kmap(page);
|
|
memset(kaddr + offset, 0, size);
|
|
flush_dcache_page(page);
|
|
flush_page_to_ram(page);
|
|
kunmap(page);
|
|
}
|
|
|
|
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);
|
|
kunmap_atomic(vfrom, KM_USER0);
|
|
kunmap_atomic(vto, KM_USER1);
|
|
}
|
|
|
|
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 */
|