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Diffstat (limited to 'arch/parisc/include/asm/mmu_context.h')
-rw-r--r--arch/parisc/include/asm/mmu_context.h80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/mmu_context.h b/arch/parisc/include/asm/mmu_context.h
new file mode 100644
index 00000000..59be2576
--- /dev/null
+++ b/arch/parisc/include/asm/mmu_context.h
@@ -0,0 +1,80 @@
+#ifndef __PARISC_MMU_CONTEXT_H
+#define __PARISC_MMU_CONTEXT_H
+
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm-generic/mm_hooks.h>
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+/* on PA-RISC, we actually have enough contexts to justify an allocator
+ * for them. prumpf */
+
+extern unsigned long alloc_sid(void);
+extern void free_sid(unsigned long);
+
+static inline int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ BUG_ON(atomic_read(&mm->mm_users) != 1);
+
+ mm->context = alloc_sid();
+ return 0;
+}
+
+static inline void
+destroy_context(struct mm_struct *mm)
+{
+ free_sid(mm->context);
+ mm->context = 0;
+}
+
+static inline unsigned long __space_to_prot(mm_context_t context)
+{
+#if SPACEID_SHIFT == 0
+ return context << 1;
+#else
+ return context >> (SPACEID_SHIFT - 1);
+#endif
+}
+
+static inline void load_context(mm_context_t context)
+{
+ mtsp(context, 3);
+ mtctl(__space_to_prot(context), 8);
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk)
+{
+
+ if (prev != next) {
+ mtctl(__pa(next->pgd), 25);
+ load_context(next->context);
+ }
+}
+
+#define deactivate_mm(tsk,mm) do { } while (0)
+
+static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
+{
+ /*
+ * Activate_mm is our one chance to allocate a space id
+ * for a new mm created in the exec path. There's also
+ * some lazy tlb stuff, which is currently dead code, but
+ * we only allocate a space id if one hasn't been allocated
+ * already, so we should be OK.
+ */
+
+ BUG_ON(next == &init_mm); /* Should never happen */
+
+ if (next->context == 0)
+ next->context = alloc_sid();
+
+ switch_mm(prev,next,current);
+}
+#endif