powerpc/mm: Fix build error with FLATMEM book3s64 config

[linux-2.6-block.git] / arch / powerpc / include / asm / book3s / 64 / mmu.h

diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index 6328857f259f5b0abe0bf56fd88c4999d012cf80..a809bdd77322783d4109be90ef0d888fdcf682df 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -2,6 +2,8 @@
 #ifndef _ASM_POWERPC_BOOK3S_64_MMU_H_
 #define _ASM_POWERPC_BOOK3S_64_MMU_H_
 
+#include <asm/page.h>
+
 #ifndef __ASSEMBLY__
 /*
  * Page size definition
@@ -24,8 +26,30 @@ struct mmu_psize_def {
 };
 extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
 
+/*
+ * For BOOK3s 64 with 4k and 64K linux page size
+ * we want to use pointers, because the page table
+ * actually store pfn
+ */
+typedef pte_t *pgtable_t;
+
 #endif /* __ASSEMBLY__ */
 
+/*
+ * If we store section details in page->flags we can't increase the MAX_PHYSMEM_BITS
+ * if we increase SECTIONS_WIDTH we will not store node details in page->flags and
+ * page_to_nid does a page->section->node lookup
+ * Hence only increase for VMEMMAP. Further depending on SPARSEMEM_EXTREME reduce
+ * memory requirements with large number of sections.
+ * 51 bits is the max physical real address on POWER9
+ */
+#if defined(CONFIG_SPARSEMEM_VMEMMAP) && defined(CONFIG_SPARSEMEM_EXTREME) &&  \
+       defined(CONFIG_PPC_64K_PAGES)
+#define MAX_PHYSMEM_BITS 51
+#else
+#define MAX_PHYSMEM_BITS 46
+#endif
+
 /* 64-bit classic hash table MMU */
 #include <asm/book3s/64/mmu-hash.h>