thp: change split_huge_page_pmd() interface

Pass vma instead of mm and add address parameter.

In most cases we already have vma on the stack. We provides
split_huge_page_pmd_mm() for few cases when we have mm, but not vma.

This change is preparation to huge zero pmd splitting implementation.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 17 insertions, 2 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 7742fb36eb4d..de6aa5f3fdd2 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2475,9 +2475,14 @@ static int khugepaged(void *none)
         return 0;
 }
 
-void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd)
+void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,
+                pmd_t *pmd)
 {
         struct page *page;
+        unsigned long haddr = address & HPAGE_PMD_MASK;
+        struct mm_struct *mm = vma->vm_mm;
+
+        BUG_ON(vma->vm_start > haddr || vma->vm_end < haddr + HPAGE_PMD_SIZE);
 
         spin_lock(&mm->page_table_lock);
         if (unlikely(!pmd_trans_huge(*pmd))) {
@@ -2495,6 +2500,16 @@ void __split_huge_page_pmd(struct mm_struct *mm, pmd_t *pmd)
         BUG_ON(pmd_trans_huge(*pmd));
 }
 
+void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
+                pmd_t *pmd)
+{
+        struct vm_area_struct *vma;
+
+        vma = find_vma(mm, address);
+        BUG_ON(vma == NULL);
+        split_huge_page_pmd(vma, address, pmd);
+}
+
 static void split_huge_page_address(struct mm_struct *mm,
                                     unsigned long address)
 {
@@ -2509,7 +2524,7 @@ static void split_huge_page_address(struct mm_struct *mm,
          * Caller holds the mmap_sem write mode, so a huge pmd cannot
          * materialize from under us.
          */
-        split_huge_page_pmd(mm, pmd);
+        split_huge_page_pmd_mm(mm, address, pmd);
 }
 
 void __vma_adjust_trans_huge(struct vm_area_struct *vma,