[OE-core] [PATCH] image_types: btrfs use sparse file creation

[Saul Wold]

This will speed up file creation and still allow the btrfs tools to
create a full btrfs image.  This is similar to what we do for ext234
FS types.

Signed-off-by: Saul Wold <sgw at linux.intel.com>
---
 meta/classes/image_types.bbclass | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/meta/classes/image_types.bbclass b/meta/classes/image_types.bbclass
index aaba1073a08..ce7699d9b60 100644
--- a/meta/classes/image_types.bbclass
+++ b/meta/classes/image_types.bbclass
@@ -104,7 +104,7 @@ IMAGE_CMD_btrfs () {
 		size=${MIN_BTRFS_SIZE}
 		bbwarn "Rootfs size is too small for BTRFS. Filesystem will be extended to ${size}K"
 	fi
-	dd if=/dev/zero of=${IMGDEPLOYDIR}/${IMAGE_NAME}${IMAGE_NAME_SUFFIX}.btrfs count=${size} bs=1024
+	dd if=/dev/zero of=${IMGDEPLOYDIR}/${IMAGE_NAME}${IMAGE_NAME_SUFFIX}.btrfs seek=${size} count=0 bs=1024
 	mkfs.btrfs ${EXTRA_IMAGECMD} -r ${IMAGE_ROOTFS} ${IMGDEPLOYDIR}/${IMAGE_NAME}${IMAGE_NAME_SUFFIX}.btrfs
 }
 
-- 
2.13.6