[PATCH 2/4] MTD parts: introduce mtd_get_device_size()

[Richard Genoud <richard.genoud@gmail.com>]

mtd_get_device_size() returns the size of the whole MTD device, that is
the mtd_info master size.
This is used by UBI to calculate the maximum number of bad blocks (MBB)
on a MTD device.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
---
 drivers/mtd/mtdpart.c          |   14 ++++++++++++++
 include/linux/mtd/partitions.h |    1 +
 2 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 8500584..d12f583 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -760,3 +760,17 @@ int mtd_is_partition(const struct mtd_info *mtd)
 	return ispart;
 }
 EXPORT_SYMBOL_GPL(mtd_is_partition);
+
+/* returns the size of an MTD device */
+uint64_t mtd_get_device_size(const struct mtd_info *mtd)
+{
+	struct mtd_part *part;
+
+	if (!mtd_is_partition(mtd))
+		return mtd->size;
+
+	part = PART(mtd);
+
+	return part->master->size;
+}
+EXPORT_SYMBOL_GPL(mtd_get_device_size);
diff --git a/include/linux/mtd/partitions.h b/include/linux/mtd/partitions.h
index 02a5115..1f8d24b 100644
--- a/include/linux/mtd/partitions.h
+++ b/include/linux/mtd/partitions.h
@@ -83,5 +83,6 @@ int mtd_is_partition(const struct mtd_info *mtd);
 int mtd_add_partition(struct mtd_info *master, char *name,
 		      long long offset, long long length);
 int mtd_del_partition(struct mtd_info *master, int partno);
+uint64_t mtd_get_device_size(const struct mtd_info *mtd);
 
 #endif
-- 
1.7.2.5