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, 61 insertions, 0 deletions

diff --git a/kernel/arch/arm64/mm/pgd.c b/kernel/arch/arm64/mm/pgd.c
new file mode 100644
index 000000000..71ca104f9
--- /dev/null
+++ b/kernel/arch/arm64/mm/pgd.c
@@ -0,0 +1,61 @@
+/*
+ * PGD allocation/freeing
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Catalin Marinas <catalin.marinas@arm.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/mm.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/slab.h>
+
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/tlbflush.h>
+
+#include "mm.h"
+
+#define PGD_SIZE	(PTRS_PER_PGD * sizeof(pgd_t))
+
+static struct kmem_cache *pgd_cache;
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+	if (PGD_SIZE == PAGE_SIZE)
+		return (pgd_t *)__get_free_page(PGALLOC_GFP);
+	else
+		return kmem_cache_alloc(pgd_cache, PGALLOC_GFP);
+}
+
+void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+	if (PGD_SIZE == PAGE_SIZE)
+		free_page((unsigned long)pgd);
+	else
+		kmem_cache_free(pgd_cache, pgd);
+}
+
+static int __init pgd_cache_init(void)
+{
+	/*
+	 * Naturally aligned pgds required by the architecture.
+	 */
+	if (PGD_SIZE != PAGE_SIZE)
+		pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE,
+					      SLAB_PANIC, NULL);
+	return 0;
+}
+core_initcall(pgd_cache_init);