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, 97 insertions, 0 deletions

diff --git a/kernel/arch/unicore32/mm/flush.c b/kernel/arch/unicore32/mm/flush.c
new file mode 100644
index 000000000..6d4c096ff
--- /dev/null
+++ b/kernel/arch/unicore32/mm/flush.c
@@ -0,0 +1,97 @@
+/*
+ * linux/arch/unicore32/mm/flush.c
+ *
+ * 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.
+ */
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+void flush_cache_mm(struct mm_struct *mm)
+{
+}
+
+void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
+		unsigned long end)
+{
+	if (vma->vm_flags & VM_EXEC)
+		__flush_icache_all();
+}
+
+void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr,
+		unsigned long pfn)
+{
+}
+
+static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
+			 unsigned long uaddr, void *kaddr, unsigned long len)
+{
+	/* VIPT non-aliasing D-cache */
+	if (vma->vm_flags & VM_EXEC) {
+		unsigned long addr = (unsigned long)kaddr;
+
+		__cpuc_coherent_kern_range(addr, addr + len);
+	}
+}
+
+/*
+ * Copy user data from/to a page which is mapped into a different
+ * processes address space.  Really, we want to allow our "user
+ * space" model to handle this.
+ *
+ * Note that this code needs to run on the current CPU.
+ */
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+		       unsigned long uaddr, void *dst, const void *src,
+		       unsigned long len)
+{
+	memcpy(dst, src, len);
+	flush_ptrace_access(vma, page, uaddr, dst, len);
+}
+
+void __flush_dcache_page(struct address_space *mapping, struct page *page)
+{
+	/*
+	 * Writeback any data associated with the kernel mapping of this
+	 * page.  This ensures that data in the physical page is mutually
+	 * coherent with the kernels mapping.
+	 */
+	__cpuc_flush_kern_dcache_area(page_address(page), PAGE_SIZE);
+}
+
+/*
+ * Ensure cache coherency between kernel mapping and userspace mapping
+ * of this page.
+ */
+void flush_dcache_page(struct page *page)
+{
+	struct address_space *mapping;
+
+	/*
+	 * The zero page is never written to, so never has any dirty
+	 * cache lines, and therefore never needs to be flushed.
+	 */
+	if (page == ZERO_PAGE(0))
+		return;
+
+	mapping = page_mapping(page);
+
+	if (mapping && !mapping_mapped(mapping))
+		clear_bit(PG_dcache_clean, &page->flags);
+	else {
+		__flush_dcache_page(mapping, page);
+		if (mapping)
+			__flush_icache_all();
+		set_bit(PG_dcache_clean, &page->flags);
+	}
+}
+EXPORT_SYMBOL(flush_dcache_page);