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, 184 insertions, 0 deletions

diff --git a/kernel/arch/powerpc/mm/tlb_hash32.c b/kernel/arch/powerpc/mm/tlb_hash32.c
new file mode 100644
index 000000000..558e30cce
--- /dev/null
+++ b/kernel/arch/powerpc/mm/tlb_hash32.c
@@ -0,0 +1,184 @@
+/*
+ * This file contains the routines for TLB flushing.
+ * On machines where the MMU uses a hash table to store virtual to
+ * physical translations, these routines flush entries from the
+ * hash table also.
+ *  -- paulus
+ *
+ *  Derived from arch/ppc/mm/init.c:
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Paul Mackerras
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/export.h>
+
+#include <asm/tlbflush.h>
+#include <asm/tlb.h>
+
+#include "mmu_decl.h"
+
+/*
+ * Called when unmapping pages to flush entries from the TLB/hash table.
+ */
+void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr)
+{
+	unsigned long ptephys;
+
+	if (Hash != 0) {
+		ptephys = __pa(ptep) & PAGE_MASK;
+		flush_hash_pages(mm->context.id, addr, ptephys, 1);
+	}
+}
+EXPORT_SYMBOL(flush_hash_entry);
+
+/*
+ * Called by ptep_set_access_flags, must flush on CPUs for which the
+ * DSI handler can't just "fixup" the TLB on a write fault
+ */
+void flush_tlb_page_nohash(struct vm_area_struct *vma, unsigned long addr)
+{
+	if (Hash != 0)
+		return;
+	_tlbie(addr);
+}
+
+/*
+ * Called at the end of a mmu_gather operation to make sure the
+ * TLB flush is completely done.
+ */
+void tlb_flush(struct mmu_gather *tlb)
+{
+	if (Hash == 0) {
+		/*
+		 * 603 needs to flush the whole TLB here since
+		 * it doesn't use a hash table.
+		 */
+		_tlbia();
+	}
+}
+
+/*
+ * TLB flushing:
+ *
+ *  - 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 kernel pages
+ *
+ * since the hardware hash table functions as an extension of the
+ * tlb as far as the linux tables are concerned, flush it too.
+ *    -- Cort
+ */
+
+static void flush_range(struct mm_struct *mm, unsigned long start,
+			unsigned long end)
+{
+	pmd_t *pmd;
+	unsigned long pmd_end;
+	int count;
+	unsigned int ctx = mm->context.id;
+
+	if (Hash == 0) {
+		_tlbia();
+		return;
+	}
+	start &= PAGE_MASK;
+	if (start >= end)
+		return;
+	end = (end - 1) | ~PAGE_MASK;
+	pmd = pmd_offset(pud_offset(pgd_offset(mm, start), start), start);
+	for (;;) {
+		pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1;
+		if (pmd_end > end)
+			pmd_end = end;
+		if (!pmd_none(*pmd)) {
+			count = ((pmd_end - start) >> PAGE_SHIFT) + 1;
+			flush_hash_pages(ctx, start, pmd_val(*pmd), count);
+		}
+		if (pmd_end == end)
+			break;
+		start = pmd_end + 1;
+		++pmd;
+	}
+}
+
+/*
+ * Flush kernel TLB entries in the given range
+ */
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	flush_range(&init_mm, start, end);
+}
+EXPORT_SYMBOL(flush_tlb_kernel_range);
+
+/*
+ * Flush all the (user) entries for the address space described by mm.
+ */
+void flush_tlb_mm(struct mm_struct *mm)
+{
+	struct vm_area_struct *mp;
+
+	if (Hash == 0) {
+		_tlbia();
+		return;
+	}
+
+	/*
+	 * It is safe to go down the mm's list of vmas when called
+	 * from dup_mmap, holding mmap_sem.  It would also be safe from
+	 * unmap_region or exit_mmap, but not from vmtruncate on SMP -
+	 * but it seems dup_mmap is the only SMP case which gets here.
+	 */
+	for (mp = mm->mmap; mp != NULL; mp = mp->vm_next)
+		flush_range(mp->vm_mm, mp->vm_start, mp->vm_end);
+}
+EXPORT_SYMBOL(flush_tlb_mm);
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
+{
+	struct mm_struct *mm;
+	pmd_t *pmd;
+
+	if (Hash == 0) {
+		_tlbie(vmaddr);
+		return;
+	}
+	mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm;
+	pmd = pmd_offset(pud_offset(pgd_offset(mm, vmaddr), vmaddr), vmaddr);
+	if (!pmd_none(*pmd))
+		flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1);
+}
+EXPORT_SYMBOL(flush_tlb_page);
+
+/*
+ * For each address in the range, find the pte for the address
+ * and check _PAGE_HASHPTE bit; if it is set, find and destroy
+ * the corresponding HPTE.
+ */
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+		     unsigned long end)
+{
+	flush_range(vma->vm_mm, start, end);
+}
+EXPORT_SYMBOL(flush_tlb_range);
+
+void __init early_init_mmu(void)
+{
+}