virtconvert.h

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#ifndef __VIRT_CONVERT__
#define __VIRT_CONVERT__

/*
 * Macros used for converting between virtual and physical mappings.
 */

#ifdef __KERNEL__

#include <linux/config.h>
#include <asm/setup.h>
#include <asm/page.h>

#ifdef CONFIG_AMIGA
#include <asm/amigahw.h>
#endif

/*
 * Change virtual addresses to physical addresses and vv.
 */
#ifndef CONFIG_SUN3
extern unsigned long mm_vtop(unsigned long addr) __attribute__ ((const));
extern unsigned long mm_vtop_fallback (unsigned long) __attribute__ ((const));
extern unsigned long mm_ptov(unsigned long addr) __attribute__ ((const));
#else
extern inline unsigned long mm_vtop(unsigned long vaddr)
{
	return __pa(vaddr);
}

extern inline unsigned long mm_ptov(unsigned long paddr)
{
	return (unsigned long)__va(paddr);
}
#endif 

#ifdef CONFIG_SINGLE_MEMORY_CHUNK
extern inline unsigned long virt_to_phys(volatile void *vaddr)
{
	unsigned long voff = (unsigned long)vaddr - PAGE_OFFSET;

	if (voff < m68k_memory[0].size)
		return voff + m68k_memory[0].addr;
	return mm_vtop_fallback((unsigned long)vaddr);
}

extern inline void * phys_to_virt(unsigned long paddr)
{
	unsigned long poff = paddr - m68k_memory[0].addr;

	if (poff < m68k_memory[0].size)
		return (void *)(poff + PAGE_OFFSET);

#ifdef CONFIG_AMIGA
	/*
	 * if on an amiga and address is in first 16M, move it 
	 * to the ZTWO_VADDR range
	 */
	if (MACH_IS_AMIGA && paddr < 16*1024*1024)
		return (void *)ZTWO_VADDR(paddr);
#endif
	return (void *)paddr;
}
#else
extern inline unsigned long virt_to_phys(volatile void * address)
{
	return mm_vtop((unsigned long)address);
}

extern inline void * phys_to_virt(unsigned long address)
{
	return (void *) mm_ptov(address);
}
#endif

/*
 * IO bus memory addresses are 1:1 with the physical address,
 * except on the PCI bus of the Hades.
 */
#ifdef CONFIG_HADES
#define virt_to_bus(a) (virt_to_phys(a) + (MACH_IS_HADES ? 0x80000000 : 0))
#define bus_to_virt(a) (phys_to_virt((a) - (MACH_IS_HADES ? 0x80000000 : 0)))
#else
#define virt_to_bus virt_to_phys
#define bus_to_virt phys_to_virt
#endif

#endif
#endif