powerpc: Use RCU based pte freeing mechanism for all powerpc

Refactor the RCU based pte free code that was used on ppc64 to be used
on all powerpc.

Additionally refactor pte_free() & pte_free_kernel() into common code
between ppc32 & ppc64.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/pgalloc.h b/arch/powerpc/include/asm/pgalloc.h
index b4505ed0f0f2..5d8480265a77 100644
--- a/arch/powerpc/include/asm/pgalloc.h
+++ b/arch/powerpc/include/asm/pgalloc.h
@@ -2,11 +2,52 @@
 #define _ASM_POWERPC_PGALLOC_H
 #ifdef __KERNEL__
 
+#include <linux/mm.h>
+
+static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+        free_page((unsigned long)pte);
+}
+
+static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
+{
+        pgtable_page_dtor(ptepage);
+        __free_page(ptepage);
+}
+
+typedef struct pgtable_free {
+        unsigned long val;
+} pgtable_free_t;
+
+#define PGF_CACHENUM_MASK       0x7
+
+static inline pgtable_free_t pgtable_free_cache(void *p, int cachenum,
+                                                unsigned long mask)
+{
+        BUG_ON(cachenum > PGF_CACHENUM_MASK);
+
+        return (pgtable_free_t){.val = ((unsigned long) p & ~mask) | cachenum};
+}
+
 #ifdef CONFIG_PPC64
 #include <asm/pgalloc-64.h>
 #else
 #include <asm/pgalloc-32.h>
 #endif
 
+extern void pgtable_free_tlb(struct mmu_gather *tlb, pgtable_free_t pgf);
+
+#ifdef CONFIG_SMP
+#define __pte_free_tlb(tlb,ptepage)     \
+do { \
+        pgtable_page_dtor(ptepage); \
+        pgtable_free_tlb(tlb, pgtable_free_cache(page_address(ptepage), \
+                PTE_NONCACHE_NUM, PTE_TABLE_SIZE-1)); \
+} while (0)
+#else
+#define __pte_free_tlb(tlb, pte)        pte_free((tlb)->mm, (pte))
+#endif
+
+
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_PGALLOC_H */