1 files changed, 140 insertions, 0 deletions

diff --git a/arch/s390/include/asm/tlbflush.h b/arch/s390/include/asm/tlbflush.h
new file mode 100644
index 000000000000..d60394b9745e
--- /dev/null
+++ b/arch/s390/include/asm/tlbflush.h
@@ -0,0 +1,140 @@
+#ifndef _S390_TLBFLUSH_H
+#define _S390_TLBFLUSH_H
+
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <asm/processor.h>
+#include <asm/pgalloc.h>
+
+/*
+ * Flush all tlb entries on the local cpu.
+ */
+static inline void __tlb_flush_local(void)
+{
+        asm volatile("ptlb" : : : "memory");
+}
+
+#ifdef CONFIG_SMP
+/*
+ * Flush all tlb entries on all cpus.
+ */
+void smp_ptlb_all(void);
+
+static inline void __tlb_flush_global(void)
+{
+        register unsigned long reg2 asm("2");
+        register unsigned long reg3 asm("3");
+        register unsigned long reg4 asm("4");
+        long dummy;
+
+#ifndef __s390x__
+        if (!MACHINE_HAS_CSP) {
+                smp_ptlb_all();
+                return;
+        }
+#endif /* __s390x__ */
+
+        dummy = 0;
+        reg2 = reg3 = 0;
+        reg4 = ((unsigned long) &dummy) + 1;
+        asm volatile(
+                "       csp     %0,%2"
+                : : "d" (reg2), "d" (reg3), "d" (reg4), "m" (dummy) : "cc" );
+}
+
+static inline void __tlb_flush_full(struct mm_struct *mm)
+{
+        cpumask_t local_cpumask;
+
+        preempt_disable();
+        /*
+         * If the process only ran on the local cpu, do a local flush.
+         */
+        local_cpumask = cpumask_of_cpu(smp_processor_id());
+        if (cpus_equal(mm->cpu_vm_mask, local_cpumask))
+                __tlb_flush_local();
+        else
+                __tlb_flush_global();
+        preempt_enable();
+}
+#else
+#define __tlb_flush_full(mm)    __tlb_flush_local()
+#endif
+
+/*
+ * Flush all tlb entries of a page table on all cpus.
+ */
+static inline void __tlb_flush_idte(unsigned long asce)
+{
+        asm volatile(
+                "       .insn   rrf,0xb98e0000,0,%0,%1,0"
+                : : "a" (2048), "a" (asce) : "cc" );
+}
+
+static inline void __tlb_flush_mm(struct mm_struct * mm)
+{
+        if (unlikely(cpus_empty(mm->cpu_vm_mask)))
+                return;
+        /*
+         * If the machine has IDTE we prefer to do a per mm flush
+         * on all cpus instead of doing a local flush if the mm
+         * only ran on the local cpu.
+         */
+        if (MACHINE_HAS_IDTE) {
+                if (mm->context.noexec)
+                        __tlb_flush_idte((unsigned long)
+                                         get_shadow_table(mm->pgd) |
+                                         mm->context.asce_bits);
+                __tlb_flush_idte((unsigned long) mm->pgd |
+                                 mm->context.asce_bits);
+                return;
+        }
+        __tlb_flush_full(mm);
+}
+
+static inline void __tlb_flush_mm_cond(struct mm_struct * mm)
+{
+        if (atomic_read(&mm->mm_users) <= 1 && mm == current->active_mm)
+                __tlb_flush_mm(mm);
+}
+
+/*
+ * TLB flushing:
+ *  flush_tlb() - flushes the current mm struct TLBs
+ *  flush_tlb_all() - flushes all processes TLBs
+ *  flush_tlb_mm(mm) - flushes the specified mm context TLB's
+ *  flush_tlb_page(vma, vmaddr) - flushes one page
+ *  flush_tlb_range(vma, start, end) - flushes a range of pages
+ *  flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
+ */
+
+/*
+ * flush_tlb_mm goes together with ptep_set_wrprotect for the
+ * copy_page_range operation and flush_tlb_range is related to
+ * ptep_get_and_clear for change_protection. ptep_set_wrprotect and
+ * ptep_get_and_clear do not flush the TLBs directly if the mm has
+ * only one user. At the end of the update the flush_tlb_mm and
+ * flush_tlb_range functions need to do the flush.
+ */
+#define flush_tlb()                             do { } while (0)
+#define flush_tlb_all()                         do { } while (0)
+#define flush_tlb_page(vma, addr)               do { } while (0)
+
+static inline void flush_tlb_mm(struct mm_struct *mm)
+{
+        __tlb_flush_mm_cond(mm);
+}
+
+static inline void flush_tlb_range(struct vm_area_struct *vma,
+                                   unsigned long start, unsigned long end)
+{
+        __tlb_flush_mm_cond(vma->vm_mm);
+}
+
+static inline void flush_tlb_kernel_range(unsigned long start,
+                                          unsigned long end)
+{
+        __tlb_flush_mm(&init_mm);
+}
+
+#endif /* _S390_TLBFLUSH_H */