powerpc/mm: Fix pgtable cache cleanup with CONFIG_PPC_SUBPAGE_PROT

[safe/jmp/linux-2.6] / arch / powerpc / include / asm / mmu-hash64.h

diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h
index 7514ec2..2102b21 100644 (file)
--- a/arch/powerpc/include/asm/mmu-hash64.h
+++ b/arch/powerpc/include/asm/mmu-hash64.h
@@ -373,6 +373,38 @@ extern void slb_set_size(u16 size);
 
 #ifndef __ASSEMBLY__
 
+#ifdef CONFIG_PPC_SUBPAGE_PROT
+/*
+ * For the sub-page protection option, we extend the PGD with one of
+ * these.  Basically we have a 3-level tree, with the top level being
+ * the protptrs array.  To optimize speed and memory consumption when
+ * only addresses < 4GB are being protected, pointers to the first
+ * four pages of sub-page protection words are stored in the low_prot
+ * array.
+ * Each page of sub-page protection words protects 1GB (4 bytes
+ * protects 64k).  For the 3-level tree, each page of pointers then
+ * protects 8TB.
+ */
+struct subpage_prot_table {
+       unsigned long maxaddr;  /* only addresses < this are protected */
+       unsigned int **protptrs[2];
+       unsigned int *low_prot[4];
+};
+
+#define SBP_L1_BITS            (PAGE_SHIFT - 2)
+#define SBP_L2_BITS            (PAGE_SHIFT - 3)
+#define SBP_L1_COUNT           (1 << SBP_L1_BITS)
+#define SBP_L2_COUNT           (1 << SBP_L2_BITS)
+#define SBP_L2_SHIFT           (PAGE_SHIFT + SBP_L1_BITS)
+#define SBP_L3_SHIFT           (SBP_L2_SHIFT + SBP_L2_BITS)
+
+extern void subpage_prot_free(struct mm_struct *mm);
+extern void subpage_prot_init_new_context(struct mm_struct *mm);
+#else
+static inline void subpage_prot_free(struct mm_struct *mm) {}
+static inline void subpage_prot_init_new_context(struct mm_struct *mm) { }
+#endif /* CONFIG_PPC_SUBPAGE_PROT */
+
 typedef unsigned long mm_context_id_t;
 
 typedef struct {
@@ -386,6 +418,9 @@ typedef struct {
        u16 sllp;               /* SLB page size encoding */
 #endif
        unsigned long vdso_base;
+#ifdef CONFIG_PPC_SUBPAGE_PROT
+       struct subpage_prot_table spt;
+#endif /* CONFIG_PPC_SUBPAGE_PROT */
 } mm_context_t;