Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/kernel/arch/mn10300/mm/mmu-context.c b/kernel/arch/mn10300/mm/mmu-context.c
new file mode 100644
index 000000000..a4f7d3dcc
--- /dev/null
+++ b/kernel/arch/mn10300/mm/mmu-context.c
@@ -0,0 +1,62 @@
+/* MN10300 MMU context allocation and management
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+
+#ifdef CONFIG_MN10300_TLB_USE_PIDR
+/*
+ * list of the MMU contexts last allocated on each CPU
+ */
+unsigned long mmu_context_cache[NR_CPUS] = {
+	[0 ... NR_CPUS - 1] =
+	MMU_CONTEXT_FIRST_VERSION * 2 - (1 - MMU_CONTEXT_TLBPID_LOCK_NR),
+};
+#endif /* CONFIG_MN10300_TLB_USE_PIDR */
+
+/*
+ * preemptively set a TLB entry
+ */
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
+{
+	unsigned long pteu, ptel, cnx, flags;
+	pte_t pte = *ptep;
+
+	addr &= PAGE_MASK;
+	ptel = pte_val(pte) & ~(xPTEL_UNUSED1 | xPTEL_UNUSED2);
+
+	/* make sure the context doesn't migrate and defend against
+	 * interference from vmalloc'd regions */
+	local_irq_save(flags);
+
+	cnx = ~MMU_NO_CONTEXT;
+#ifdef CONFIG_MN10300_TLB_USE_PIDR
+	cnx = mm_context(vma->vm_mm);
+#endif
+
+	if (cnx != MMU_NO_CONTEXT) {
+		pteu = addr;
+#ifdef CONFIG_MN10300_TLB_USE_PIDR
+		pteu |= cnx & MMU_CONTEXT_TLBPID_MASK;
+#endif
+		if (!(pte_val(pte) & _PAGE_NX)) {
+			IPTEU = pteu;
+			if (IPTEL & xPTEL_V)
+				IPTEL = ptel;
+		}
+		DPTEU = pteu;
+		if (DPTEL & xPTEL_V)
+			DPTEL = ptel;
+	}
+
+	local_irq_restore(flags);
+}