1 files changed, 16 insertions, 22 deletions

diff --git a/mm/nommu.c b/mm/nommu.c
index 5afce48ce339..0b16cb4c517b 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -680,9 +680,9 @@ static void protect_vma(struct vm_area_struct *vma, unsigned long flags)
  */
 static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
 {
-        struct vm_area_struct *pvma, **pp, *next;
+        struct vm_area_struct *pvma, *prev;
         struct address_space *mapping;
-        struct rb_node **p, *parent;
+        struct rb_node **p, *parent, *rb_prev;
 
         kenter(",%p", vma);
 
@@ -703,7 +703,7 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
         }
 
         /* add the VMA to the tree */
-        parent = NULL;
+        parent = rb_prev = NULL;
         p = &mm->mm_rb.rb_node;
         while (*p) {
                 parent = *p;
@@ -713,17 +713,20 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
                  * (the latter is necessary as we may get identical VMAs) */
                 if (vma->vm_start < pvma->vm_start)
                         p = &(*p)->rb_left;
-                else if (vma->vm_start > pvma->vm_start)
+                else if (vma->vm_start > pvma->vm_start) {
+                        rb_prev = parent;
                         p = &(*p)->rb_right;
-                else if (vma->vm_end < pvma->vm_end)
+                } else if (vma->vm_end < pvma->vm_end)
                         p = &(*p)->rb_left;
-                else if (vma->vm_end > pvma->vm_end)
+                else if (vma->vm_end > pvma->vm_end) {
+                        rb_prev = parent;
                         p = &(*p)->rb_right;
-                else if (vma < pvma)
+                } else if (vma < pvma)
                         p = &(*p)->rb_left;
-                else if (vma > pvma)
+                else if (vma > pvma) {
+                        rb_prev = parent;
                         p = &(*p)->rb_right;
-                else
+                } else
                         BUG();
         }
 
@@ -731,20 +734,11 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
         rb_insert_color(&vma->vm_rb, &mm->mm_rb);
 
         /* add VMA to the VMA list also */
-        for (pp = &mm->mmap; (pvma = *pp); pp = &(*pp)->vm_next) {
-                if (pvma->vm_start > vma->vm_start)
-                        break;
-                if (pvma->vm_start < vma->vm_start)
-                        continue;
-                if (pvma->vm_end < vma->vm_end)
-                        break;
-        }
+        prev = NULL;
+        if (rb_prev)
+                prev = rb_entry(rb_prev, struct vm_area_struct, vm_rb);
 
-        next = *pp;
-        *pp = vma;
-        vma->vm_next = next;
-        if (next)
-                next->vm_prev = vma;
+        __vma_link_list(mm, vma, prev, parent);
 }
 
 /*