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-rw-r--r--arch/unicore32/include/asm/mmu_context.h87
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/unicore32/include/asm/mmu_context.h b/arch/unicore32/include/asm/mmu_context.h
new file mode 100644
index 000000000000..fb5e4c658f7a
--- /dev/null
+++ b/arch/unicore32/include/asm/mmu_context.h
@@ -0,0 +1,87 @@
+/*
+ * linux/arch/unicore32/include/asm/mmu_context.h
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __UNICORE_MMU_CONTEXT_H__
+#define __UNICORE_MMU_CONTEXT_H__
+
+#include <linux/compiler.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cpu-single.h>
+
+#define init_new_context(tsk, mm) 0
+
+#define destroy_context(mm) do { } while (0)
+
+/*
+ * This is called when "tsk" is about to enter lazy TLB mode.
+ *
+ * mm: describes the currently active mm context
+ * tsk: task which is entering lazy tlb
+ * cpu: cpu number which is entering lazy tlb
+ *
+ * tsk->mm will be NULL
+ */
+static inline void
+enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+/*
+ * This is the actual mm switch as far as the scheduler
+ * is concerned. No registers are touched. We avoid
+ * calling the CPU specific function when the mm hasn't
+ * actually changed.
+ */
+static inline void
+switch_mm(struct mm_struct *prev, struct mm_struct *next,
+ struct task_struct *tsk)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next)
+ cpu_switch_mm(next->pgd, next);
+}
+
+#define deactivate_mm(tsk, mm) do { } while (0)
+#define activate_mm(prev, next) switch_mm(prev, next, NULL)
+
+/*
+ * We are inserting a "fake" vma for the user-accessible vector page so
+ * gdb and friends can get to it through ptrace and /proc/<pid>/mem.
+ * But we also want to remove it before the generic code gets to see it
+ * during process exit or the unmapping of it would cause total havoc.
+ * (the macro is used as remove_vma() is static to mm/mmap.c)
+ */
+#define arch_exit_mmap(mm) \
+do { \
+ struct vm_area_struct *high_vma = find_vma(mm, 0xffff0000); \
+ if (high_vma) { \
+ BUG_ON(high_vma->vm_next); /* it should be last */ \
+ if (high_vma->vm_prev) \
+ high_vma->vm_prev->vm_next = NULL; \
+ else \
+ mm->mmap = NULL; \
+ rb_erase(&high_vma->vm_rb, &mm->mm_rb); \
+ mm->mmap_cache = NULL; \
+ mm->map_count--; \
+ remove_vma(high_vma); \
+ } \
+} while (0)
+
+static inline void arch_dup_mmap(struct mm_struct *oldmm,
+ struct mm_struct *mm)
+{
+}
+
+#endif