From 7d74275d39def4d3ccc8cf4725388bf79ef13861 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 16 Nov 2012 13:55:46 -0800 Subject: 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 Link: http://lkml.kernel.org/r/20121116215356.8521.92472.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin --- arch/x86/mm/physaddr.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'arch/x86/mm') diff --git a/arch/x86/mm/physaddr.c b/arch/x86/mm/physaddr.c index fd40d75109ef..c73feddd518d 100644 --- a/arch/x86/mm/physaddr.c +++ b/arch/x86/mm/physaddr.c @@ -28,6 +28,17 @@ unsigned long __phys_addr(unsigned long x) return x; } EXPORT_SYMBOL(__phys_addr); + +unsigned long __phys_addr_symbol(unsigned long x) +{ + unsigned long y = x - __START_KERNEL_map; + + /* only check upper bounds since lower bounds will trigger carry */ + VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE); + + return y + phys_base; +} +EXPORT_SYMBOL(__phys_addr_symbol); #endif bool __virt_addr_valid(unsigned long x) -- cgit v1.2.1