x86: track memtype for RAM in page struct

Track the memtype for RAM pages in page struct instead of using the
memtype list. This avoids the explosion in the number of entries in
memtype list (of the order of 20,000 with AGP) and makes the PAT
tracking simpler.

We are using PG_arch_1 bit in page->flags.

We still use the memtype list for non RAM pages.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/asm-x86/cacheflush.h b/include/asm-x86/cacheflush.h
index 8e205a131250..092b9b4eb003 100644
--- a/include/asm-x86/cacheflush.h
+++ b/include/asm-x86/cacheflush.h
@@ -24,6 +24,8 @@
 #define copy_from_user_page(vma, page, vaddr, dst, src, len)    \
         memcpy((dst), (src), (len))
 
+#define PG_non_WB                               PG_arch_1
+PAGEFLAG(NonWB, non_WB)
 
 /*
  * The set_memory_* API can be used to change various attributes of a virtual