patch-2.4.0-test12 linux/include/asm-parisc/mmu_context.h

• Lines: 68
• Date: Tue Dec 5 12:29:39 2000
• Orig file: v2.4.0-test11/linux/include/asm-parisc/mmu_context.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.0-test11/linux/include/asm-parisc/mmu_context.h linux/include/asm-parisc/mmu_context.h
@@ -0,0 +1,67 @@
+#ifndef __PARISC_MMU_CONTEXT_H
+#define __PARISC_MMU_CONTEXT_H
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk, unsigned cpu)
+{
+}
+
+/* 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)
+{
+	/*
+	 * Init_new_context can be called for a cloned mm, so we
+	 * only allocate a space id if one hasn't been allocated
+	 * yet AND mm != &init_mm (cloned kernel thread which
+	 * will run in the kernel space with spaceid 0).
+	 */
+
+	if ((mm != &init_mm) && (mm->context == 0)) {
+		mm->context = alloc_sid();
+	}
+
+	return 0;
+}
+
+static inline void
+destroy_context(struct mm_struct *mm)
+{
+	free_sid(mm->context);
+	mm->context = 0;
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk, unsigned cpu)
+{
+
+	if (prev != next) {
+		/* Re-load page tables */
+		tsk->thread.pg_tables = __pa(next->pgd);
+
+		mtctl(tsk->thread.pg_tables, 25);
+		mtsp(next->context,3);
+	}
+}
+
+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.
+	 */
+
+	if (next == &init_mm) BUG(); /* Should never happen */
+
+	if (next->context == 0)
+	    next->context = alloc_sid();
+
+	switch_mm(prev,next,current,0);
+}
+#endif