mips: use generic fixmap.h

#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)

#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)

#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))

#define __virt_to_fix(x)	((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)

extern void __this_fixmap_does_not_exist(void);

/*

 * 'index to address' translation. If anyone tries to use the idx

 * directly without tranlation, we catch the bug with a NULL-deference

 * kernel oops. Illegal ranges of incoming indices are caught too.

 */

static inline unsigned long fix_to_virt(const unsigned int idx)

{

	/*

	 * this branch gets completely eliminated after inlining,

	 * except when someone tries to use fixaddr indices in an

	 * illegal way. (such as mixing up address types or using

	 * out-of-range indices).

	 *

	 * If it doesn't get removed, the linker will complain

	 * loudly with a reasonably clear error message..

	 */

	if (idx >= __end_of_fixed_addresses)

		__this_fixmap_does_not_exist();

	return __fix_to_virt(idx);

}

static inline unsigned long virt_to_fix(const unsigned long vaddr)

{

	BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);

	return __virt_to_fix(vaddr);

}

#include <asm-generic/fixmap.h>

#define kmap_get_fixmap_pte(vaddr)					\

	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))