1 files changed, 153 insertions, 0 deletions

diff --git a/include/asm-s390/tlbflush.h b/include/asm-s390/tlbflush.h
new file mode 100644
index 000000000000..1bb73b0e61fa
--- /dev/null
+++ b/include/asm-s390/tlbflush.h
@@ -0,0 +1,153 @@
+#ifndef _S390_TLBFLUSH_H
+#define _S390_TLBFLUSH_H
+
+#include <linux/config.h>
+#include <linux/mm.h>
+#include <asm/processor.h>
+
+/*
+ * 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_pgtables(mm, start, end) flushes a range of page tables
+ */
+
+/*
+ * S/390 has three ways of flushing TLBs
+ * 'ptlb' does a flush of the local processor
+ * 'csp' flushes the TLBs on all PUs of a SMP
+ * 'ipte' invalidates a pte in a page table and flushes that out of
+ * the TLBs of all PUs of a SMP
+ */
+
+#define local_flush_tlb() \
+do {  __asm__ __volatile__("ptlb": : :"memory"); } while (0)
+
+#ifndef CONFIG_SMP
+
+/*
+ * We always need to flush, since s390 does not flush tlb
+ * on each context switch
+ */
+
+static inline void flush_tlb(void)
+{
+        local_flush_tlb();
+}
+static inline void flush_tlb_all(void)
+{
+        local_flush_tlb();
+}
+static inline void flush_tlb_mm(struct mm_struct *mm) 
+{
+        local_flush_tlb();
+}
+static inline void flush_tlb_page(struct vm_area_struct *vma,
+                                  unsigned long addr)
+{
+        local_flush_tlb();
+}
+static inline void flush_tlb_range(struct vm_area_struct *vma,
+                                   unsigned long start, unsigned long end)
+{
+        local_flush_tlb();
+}
+
+#define flush_tlb_kernel_range(start, end) \
+        local_flush_tlb();
+
+#else
+
+#include <asm/smp.h>
+
+extern void smp_ptlb_all(void);
+
+static inline void global_flush_tlb(void)
+{
+#ifndef __s390x__
+        if (!MACHINE_HAS_CSP) {
+                smp_ptlb_all();
+                return;
+        }
+#endif /* __s390x__ */
+        {
+                register unsigned long addr asm("4");
+                long dummy;
+
+                dummy = 0;
+                addr = ((unsigned long) &dummy) + 1;
+                __asm__ __volatile__ (
+                        "    slr  2,2\n"
+                        "    slr  3,3\n"
+                        "    csp  2,%0"
+                        : : "a" (addr), "m" (dummy) : "cc", "2", "3" );
+        }
+}
+
+/*
+ * We only have to do global flush of tlb if process run since last
+ * flush on any other pu than current. 
+ * If we have threads (mm->count > 1) we always do a global flush, 
+ * since the process runs on more than one processor at the same time.
+ */
+
+static inline void __flush_tlb_mm(struct mm_struct * mm)
+{
+        cpumask_t local_cpumask;
+
+        if (unlikely(cpus_empty(mm->cpu_vm_mask)))
+                return;
+        if (MACHINE_HAS_IDTE) {
+                asm volatile (".insn rrf,0xb98e0000,0,%0,%1,0"
+                              : : "a" (2048),
+                              "a" (__pa(mm->pgd)&PAGE_MASK) : "cc" );
+                return;
+        }
+        preempt_disable();
+        local_cpumask = cpumask_of_cpu(smp_processor_id());
+        if (cpus_equal(mm->cpu_vm_mask, local_cpumask))
+                local_flush_tlb();
+        else
+                global_flush_tlb();
+        preempt_enable();
+}
+
+static inline void flush_tlb(void)
+{
+        __flush_tlb_mm(current->mm);
+}
+static inline void flush_tlb_all(void)
+{
+        global_flush_tlb();
+}
+static inline void flush_tlb_mm(struct mm_struct *mm) 
+{
+        __flush_tlb_mm(mm); 
+}
+static inline void flush_tlb_page(struct vm_area_struct *vma,
+                                  unsigned long addr)
+{
+        __flush_tlb_mm(vma->vm_mm);
+}
+static inline void flush_tlb_range(struct vm_area_struct *vma,
+                                   unsigned long start, unsigned long end)
+{
+        __flush_tlb_mm(vma->vm_mm); 
+}
+
+#define flush_tlb_kernel_range(start, end) global_flush_tlb()
+
+#endif
+
+static inline void flush_tlb_pgtables(struct mm_struct *mm,
+                                      unsigned long start, unsigned long end)
+{
+        /* S/390 does not keep any page table caches in TLB */
+}
+
+#endif /* _S390_TLBFLUSH_H */