linux/arch/x86/include/asm/page_64.h
Alexander Duyck 7d74275d39 x86: Make it so that __pa_symbol can only process kernel symbols on x86_64
I submitted an earlier patch that make __phys_addr an inline.  This obviously
results in an increase in the code size.  One step I can take to reduce that
is to make it so that the __pa_symbol call does a direct translation for
kernel addresses instead of covering all of virtual memory.

On my system this reduced the size for __pa_symbol from 5 instructions
totalling 30 bytes to 3 instructions totalling 16 bytes.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Link: http://lkml.kernel.org/r/20121116215356.8521.92472.stgit@ahduyck-cp1.jf.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-11-16 16:42:09 -08:00

43 lines
1000 B
C

#ifndef _ASM_X86_PAGE_64_H
#define _ASM_X86_PAGE_64_H
#include <asm/page_64_types.h>
#ifndef __ASSEMBLY__
/* duplicated to the one in bootmem.h */
extern unsigned long max_pfn;
extern unsigned long phys_base;
static inline unsigned long __phys_addr_nodebug(unsigned long x)
{
unsigned long y = x - __START_KERNEL_map;
/* use the carry flag to determine if x was < __START_KERNEL_map */
x = y + ((x > y) ? phys_base : (__START_KERNEL_map - PAGE_OFFSET));
return x;
}
#ifdef CONFIG_DEBUG_VIRTUAL
extern unsigned long __phys_addr(unsigned long);
extern unsigned long __phys_addr_symbol(unsigned long);
#else
#define __phys_addr(x) __phys_addr_nodebug(x)
#define __phys_addr_symbol(x) \
((unsigned long)(x) - __START_KERNEL_map + phys_base)
#endif
#define __phys_reloc_hide(x) (x)
#ifdef CONFIG_FLATMEM
#define pfn_valid(pfn) ((pfn) < max_pfn)
#endif
void clear_page(void *page);
void copy_page(void *to, void *from);
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PAGE_64_H */