linux/arch/arm/include/asm/mach/map.h
Russell King ebd4922ecc ARM: implement basic NX support for kernel lowmem mappings
Add basic NX support for kernel lowmem mappings.  We mark any section
which does not overlap kernel text as non-executable, preventing it
from being used to write code and then execute directly from there.

This does not change the alignment of the sections, so the kernel
image doesn't grow significantly via this change, so we can do this
without needing a config option.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-12-11 09:53:16 +00:00

66 lines
1.5 KiB
C

/*
* arch/arm/include/asm/map.h
*
* Copyright (C) 1999-2000 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Page table mapping constructs and function prototypes
*/
#ifndef __ASM_MACH_MAP_H
#define __ASM_MACH_MAP_H
#include <asm/io.h>
struct map_desc {
unsigned long virtual;
unsigned long pfn;
unsigned long length;
unsigned int type;
};
/* types 0-3 are defined in asm/io.h */
enum {
MT_UNCACHED = 4,
MT_CACHECLEAN,
MT_MINICLEAN,
MT_LOW_VECTORS,
MT_HIGH_VECTORS,
MT_MEMORY_RWX,
MT_MEMORY_RW,
MT_ROM,
MT_MEMORY_RWX_NONCACHED,
MT_MEMORY_RW_DTCM,
MT_MEMORY_RWX_ITCM,
MT_MEMORY_RW_SO,
MT_MEMORY_DMA_READY,
};
#ifdef CONFIG_MMU
extern void iotable_init(struct map_desc *, int);
extern void vm_reserve_area_early(unsigned long addr, unsigned long size,
void *caller);
#ifdef CONFIG_DEBUG_LL
extern void debug_ll_addr(unsigned long *paddr, unsigned long *vaddr);
extern void debug_ll_io_init(void);
#else
static inline void debug_ll_io_init(void) {}
#endif
struct mem_type;
extern const struct mem_type *get_mem_type(unsigned int type);
/*
* external interface to remap single page with appropriate type
*/
extern int ioremap_page(unsigned long virt, unsigned long phys,
const struct mem_type *mtype);
#else
#define iotable_init(map,num) do { } while (0)
#define vm_reserve_area_early(a,s,c) do { } while (0)
#endif
#endif