From e85ac0e8a745d4db0c62ee149c5c33767c19386e Mon Sep 17 00:00:00 2001
From: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Date: Mon, 8 Oct 2012 16:30:21 -0700
Subject: [PATCH] --- yaml --- r: 332381 b: refs/heads/master c:
 274023da1e8a49efa6fd9bf857f8557e5db44cdf h: refs/heads/master i:   332379:
 cd13d7bb22aed6420ec8cb8e817e7a6b62e913fb v: v3

---
 [refs]                       |  2 +-
 trunk/arch/s390/mm/pgtable.c | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index ad312aa212c2..c582228a9c14 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9501d09fa3c4ca18971083dfb0c9aa1afc85f19c
+refs/heads/master: 274023da1e8a49efa6fd9bf857f8557e5db44cdf
diff --git a/trunk/arch/s390/mm/pgtable.c b/trunk/arch/s390/mm/pgtable.c
index 1ca371a06516..e86a523875eb 100644
--- a/trunk/arch/s390/mm/pgtable.c
+++ b/trunk/arch/s390/mm/pgtable.c
@@ -787,6 +787,30 @@ void tlb_remove_table(struct mmu_gather *tlb, void *table)
 		tlb_table_flush(tlb);
 }
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+void thp_split_vma(struct vm_area_struct *vma)
+{
+	unsigned long addr;
+	struct page *page;
+
+	for (addr = vma->vm_start; addr < vma->vm_end; addr += PAGE_SIZE) {
+		page = follow_page(vma, addr, FOLL_SPLIT);
+	}
+}
+
+void thp_split_mm(struct mm_struct *mm)
+{
+	struct vm_area_struct *vma = mm->mmap;
+
+	while (vma != NULL) {
+		thp_split_vma(vma);
+		vma->vm_flags &= ~VM_HUGEPAGE;
+		vma->vm_flags |= VM_NOHUGEPAGE;
+		vma = vma->vm_next;
+	}
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
 /*
  * switch on pgstes for its userspace process (for kvm)
  */
@@ -824,6 +848,12 @@ int s390_enable_sie(void)
 	if (!mm)
 		return -ENOMEM;
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	/* split thp mappings and disable thp for future mappings */
+	thp_split_mm(mm);
+	mm->def_flags |= VM_NOHUGEPAGE;
+#endif
+
 	/* Now lets check again if something happened */
 	task_lock(tsk);
 	if (!tsk->mm || atomic_read(&tsk->mm->mm_users) > 1 ||