74 lines
2.3 KiB
C
74 lines
2.3 KiB
C
/*
|
|
* Fixmap support for Hexagon - enough to support highmem features
|
|
*
|
|
* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 and
|
|
* only version 2 as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
* 02110-1301, USA.
|
|
*/
|
|
|
|
#ifndef _ASM_FIXMAP_H
|
|
#define _ASM_FIXMAP_H
|
|
|
|
/*
|
|
* A lot of the fixmap info is already in mem-layout.h
|
|
*/
|
|
#include <asm/mem-layout.h>
|
|
|
|
/*
|
|
* Full fixmap support involves set_fixmap() functions, but
|
|
* these may not be needed if all we're after is an area for
|
|
* highmem kernel mappings.
|
|
*/
|
|
#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);
|
|
|
|
/**
|
|
* fix_to_virt -- "index to address" translation.
|
|
*
|
|
* If anyone tries to use the idx directly without translation,
|
|
* 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);
|
|
}
|
|
|
|
#define kmap_get_fixmap_pte(vaddr) \
|
|
pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), \
|
|
(vaddr)), (vaddr)), (vaddr))
|
|
|
|
#endif
|