From: "Martin J. Bligh" Fix pfn_valid for architctures with discontiguous memory. This only changes the NUMA definition, and it leaves the NUMA-Q definition as was, because it's faster that way, it's in hotpaths, and our memory is always contiguous. --- include/asm-i386/mmzone.h | 19 ++++++++++++------- 1 files changed, 12 insertions(+), 7 deletions(-) diff -puN include/asm-i386/mmzone.h~ia32-discontig-pfn_valid-fix include/asm-i386/mmzone.h --- 25/include/asm-i386/mmzone.h~ia32-discontig-pfn_valid-fix 2004-02-09 09:34:23.000000000 -0800 +++ 25-akpm/include/asm-i386/mmzone.h 2004-02-09 09:34:23.000000000 -0800 @@ -80,14 +80,19 @@ extern struct pglist_data *node_data[]; + __zone->zone_start_pfn; \ }) #define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)) -/* - * pfn_valid should be made as fast as possible, and the current definition - * is valid for machines that are NUMA, but still contiguous, which is what - * is currently supported. A more generalised, but slower definition would - * be something like this - mbligh: - * ( pfn_to_pgdat(pfn) && ((pfn) < node_end_pfn(pfn_to_nid(pfn))) ) - */ + +#ifdef CONFIG_X86_NUMAQ /* we have contiguous memory on NUMA-Q */ #define pfn_valid(pfn) ((pfn) < num_physpages) +#else +static inline int pfn_valid(int pfn) +{ + int nid = pfn_to_nid(pfn); + + if (nid >= 0) + return (pfn < node_end_pfn(nid)); + return 0; +} +#endif /* * generic node memory support, the following assumptions apply: _