[PATCH] Use page_to_pfn in BIO code

[Anton Blanchard]

Hi,

While porting the DISCONTIGMEM code to ppc64 (in order to do NUMA memory
allocation) I noticed the bio code uses page_to_phys. We should instead
be using the recently introduced page_to_pfn code.

This now limits the direct usage of mem_map (at least on ppc64) to 
two spots - page_to_pfn/pfn_to_page which makes DISCONTIGMEM support
quite trivial.

Anton

diff -urN linux-2.5_ppc64/include/linux/bio.h linux-2.5_work/include/linux/bio.h
--- linux-2.5_ppc64/include/linux/bio.h	Wed May  8 10:31:25 2002
+++ linux-2.5_work/include/linux/bio.h	Tue Jun  4 16:20:41 2002
@@ -128,8 +130,8 @@
 /*
  * will die
  */
-#define bio_to_phys(bio)	(page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
-#define bvec_to_phys(bv)	(page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
+#define bio_to_phys(bio)	((page_to_pfn(bio_page((bio))) << PAGE_SHIFT) + (unsigned long) bio_offset((bio)))
+#define bvec_to_phys(bv)	((page_to_pfn((bv)->bv_page) << PAGE_SHIFT) + (unsigned long) (bv)->bv_offset)
 
 /*
  * queues that have highmem support enabled may still need to revert to