1 files changed, 40 insertions, 0 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index d9c77b2dbe9d..ee2298936fe6 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1043,6 +1043,46 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 }
 EXPORT_SYMBOL(do_mmap_pgoff);
 
+SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
+                unsigned long, prot, unsigned long, flags,
+                unsigned long, fd, unsigned long, pgoff)
+{
+        struct file *file = NULL;
+        unsigned long retval = -EBADF;
+
+        if (!(flags & MAP_ANONYMOUS)) {
+                if (unlikely(flags & MAP_HUGETLB))
+                        return -EINVAL;
+                file = fget(fd);
+                if (!file)
+                        goto out;
+        } else if (flags & MAP_HUGETLB) {
+                struct user_struct *user = NULL;
+                /*
+                 * VM_NORESERVE is used because the reservations will be
+                 * taken when vm_ops->mmap() is called
+                 * A dummy user value is used because we are not locking
+                 * memory so no accounting is necessary
+                 */
+                len = ALIGN(len, huge_page_size(&default_hstate));
+                file = hugetlb_file_setup(HUGETLB_ANON_FILE, len, VM_NORESERVE,
+                                                &user, HUGETLB_ANONHUGE_INODE);
+                if (IS_ERR(file))
+                        return PTR_ERR(file);
+        }
+
+        flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
+
+        down_write(&current->mm->mmap_sem);
+        retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+        up_write(&current->mm->mmap_sem);
+
+        if (file)
+                fput(file);
+out:
+        return retval;
+}
+
 /*
  * Some shared mappigns will want the pages marked read-only
  * to track write events. If so, we'll downgrade vm_page_prot