File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/parisc/include/asm/tlbflush.h b/arch/parisc/include/asm/tlbflush.h
new file mode 100644
index 0000000..e84b964
--- /dev/null
+++ b/arch/parisc/include/asm/tlbflush.h
@@ -0,0 +1,91 @@
+#ifndef _PARISC_TLBFLUSH_H
+#define _PARISC_TLBFLUSH_H
+
+/* TLB flushing routines.... */
+
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <asm/mmu_context.h>
+
+
+/* This is for the serialisation of PxTLB broadcasts. At least on the
+ * N class systems, only one PxTLB inter processor broadcast can be
+ * active at any one time on the Merced bus. This tlb purge
+ * synchronisation is fairly lightweight and harmless so we activate
+ * it on all systems not just the N class.
+
+ * It is also used to ensure PTE updates are atomic and consistent
+ * with the TLB.
+ */
+extern spinlock_t pa_tlb_lock;
+
+#define purge_tlb_start(flags) spin_lock_irqsave(&pa_tlb_lock, flags)
+#define purge_tlb_end(flags) spin_unlock_irqrestore(&pa_tlb_lock, flags)
+
+extern void flush_tlb_all(void);
+extern void flush_tlb_all_local(void *);
+
+#define smp_flush_tlb_all() flush_tlb_all()
+
+int __flush_tlb_range(unsigned long sid,
+ unsigned long start, unsigned long end);
+
+#define flush_tlb_range(vma, start, end) \
+ __flush_tlb_range((vma)->vm_mm->context, start, end)
+
+#define flush_tlb_kernel_range(start, end) \
+ __flush_tlb_range(0, start, end)
+
+/*
+ * flush_tlb_mm()
+ *
+ * The code to switch to a new context is NOT valid for processes
+ * which play with the space id's. Thus, we have to preserve the
+ * space and just flush the entire tlb. However, the compilers,
+ * dynamic linker, etc, do not manipulate space id's, so there
+ * could be a significant performance benefit in switching contexts
+ * and not flushing the whole tlb.
+ */
+
+static inline void flush_tlb_mm(struct mm_struct *mm)
+{
+ BUG_ON(mm == &init_mm); /* Should never happen */
+
+#if 1 || defined(CONFIG_SMP)
+ /* Except for very small threads, flushing the whole TLB is
+ * faster than using __flush_tlb_range. The pdtlb and pitlb
+ * instructions are very slow because of the TLB broadcast.
+ * It might be faster to do local range flushes on all CPUs
+ * on PA 2.0 systems.
+ */
+ flush_tlb_all();
+#else
+ /* FIXME: currently broken, causing space id and protection ids
+ * to go out of sync, resulting in faults on userspace accesses.
+ * This approach needs further investigation since running many
+ * small applications (e.g., GCC testsuite) is faster on HP-UX.
+ */
+ if (mm) {
+ if (mm->context != 0)
+ free_sid(mm->context);
+ mm->context = alloc_sid();
+ if (mm == current->active_mm)
+ load_context(mm->context);
+ }
+#endif
+}
+
+static inline void flush_tlb_page(struct vm_area_struct *vma,
+ unsigned long addr)
+{
+ unsigned long flags, sid;
+
+ sid = vma->vm_mm->context;
+ purge_tlb_start(flags);
+ mtsp(sid, 1);
+ pdtlb(addr);
+ if (unlikely(split_tlb))
+ pitlb(addr);
+ purge_tlb_end(flags);
+}
+#endif