mtd: do not use mtd->get_unmapped_area directly

Remove direct usage of mtd->get_unmapped_area. Instead, just call
'mtd_get_unmapped_area()' which will return -EOPNOTSUPP if the function
is not implemented and test for this error code.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/mtdchar.c

@@ -1124,25 +1124,21 @@ static unsigned long mtdchar_get_unmapped_area(struct file *file,
 {
 	struct mtd_file_info *mfi = file->private_data;
 	struct mtd_info *mtd = mfi->mtd;
+	unsigned long offset;
+	int ret;
 
-	if (mtd->get_unmapped_area) {
-		unsigned long offset;
-
-		if (addr != 0)
-			return (unsigned long) -EINVAL;
-
-		if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
-			return (unsigned long) -EINVAL;
+	if (addr != 0)
+		return (unsigned long) -EINVAL;
 
-		offset = pgoff << PAGE_SHIFT;
-		if (offset > mtd->size - len)
-			return (unsigned long) -EINVAL;
+	if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
+		return (unsigned long) -EINVAL;
 
-		return mtd_get_unmapped_area(mtd, len, offset, flags);
-	}
+	offset = pgoff << PAGE_SHIFT;
+	if (offset > mtd->size - len)
+		return (unsigned long) -EINVAL;
 
-	/* can't map directly */
-	return (unsigned long) -ENOSYS;
+	ret = mtd_get_unmapped_area(mtd, len, offset, flags);
+	return ret == -EOPNOTSUPP ? -ENOSYS : ret;
 }
 #endif
 

drivers/mtd/mtdconcat.c

@@ -726,11 +726,7 @@ static unsigned long concat_get_unmapped_area(struct mtd_info *mtd,
 		if (offset + len > subdev->size)
 			return (unsigned long) -EINVAL;
 
-		if (subdev->get_unmapped_area)
-			return mtd_get_unmapped_area(subdev, len, offset,
-						     flags);
-
-		break;
+		return mtd_get_unmapped_area(subdev, len, offset, flags);
 	}
 
 	return (unsigned long) -ENOSYS;

include/linux/mtd/mtd.h

@@ -280,6 +280,8 @@ static inline unsigned long mtd_get_unmapped_area(struct mtd_info *mtd,
 						  unsigned long offset,
 						  unsigned long flags)
 {
+	if (!mtd->get_unmapped_area)
+		return -EOPNOTSUPP;
 	return mtd->get_unmapped_area(mtd, len, offset, flags);
 }