VM: add "vm_brk()" helper function

[linux-flexiantxendom0-3.2.10.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index a7bf6a3..df51891 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -240,6 +240,8 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
        return next;
 }
 
+static unsigned long do_brk(unsigned long addr, unsigned long len);
+
 SYSCALL_DEFINE1(brk, unsigned long, brk)
 {
        unsigned long rlim, retval;
@@ -2136,7 +2138,7 @@ static inline void verify_mm_writelocked(struct mm_struct *mm)
  *  anonymous maps.  eventually we may be able to do some
  *  brk-specific accounting here.
  */
-unsigned long do_brk(unsigned long addr, unsigned long len)
+static unsigned long do_brk(unsigned long addr, unsigned long len)
 {
        struct mm_struct * mm = current->mm;
        struct vm_area_struct * vma, * prev;
@@ -2232,7 +2234,17 @@ out:
        return addr;
 }
 
-EXPORT_SYMBOL(do_brk);
+unsigned long vm_brk(unsigned long addr, unsigned long len)
+{
+       struct mm_struct *mm = current->mm;
+       unsigned long ret;
+
+       down_write(&mm->mmap_sem);
+       ret = do_brk(addr, len);
+       up_write(&mm->mmap_sem);
+       return ret;
+}
+EXPORT_SYMBOL(vm_brk);
 
 /* Release all mmaps. */
 void exit_mmap(struct mm_struct *mm)