[PATCH] NOMMU: supply get_unmapped_area() to fix NOMMU SYSV SHM

Supply a get_unmapped_area() to fix NOMMU SYSV SHM support. Signed-off-by: David Howells <[email protected]> Acked-by: Adam Litke <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
Baughn · Mar 23, 2007 · d56e03c · d56e03c
1 parent 8da38d7
commit d56e03c
Showing 1 changed file with 22 additions and 0 deletions.
diff --git a/mm/nommu.c b/mm/nommu.c
@@ -1192,6 +1192,28 @@ void unmap_mapping_range(struct address_space *mapping,
 }
 EXPORT_SYMBOL(unmap_mapping_range);
 
+/*
+ * ask for an unmapped area at which to create a mapping on a file
+ */
+unsigned long get_unmapped_area(struct file *file, unsigned long addr,
+				unsigned long len, unsigned long pgoff,
+				unsigned long flags)
+{
+	unsigned long (*get_area)(struct file *, unsigned long, unsigned long,
+				  unsigned long, unsigned long);
+
+	get_area = current->mm->get_unmapped_area;
+	if (file && file->f_op && file->f_op->get_unmapped_area)
+		get_area = file->f_op->get_unmapped_area;
+
+	if (!get_area)
+		return -ENOSYS;
+
+	return get_area(file, addr, len, pgoff, flags);
+}
+
+EXPORT_SYMBOL(get_unmapped_area);
+
 /*
  * Check that a process has enough memory to allocate a new virtual
  * mapping. 0 means there is enough memory for the allocation to