wic: Use overhead factor when creating partitions from rootfs directories

When creating partitions sized to given rootfs directories, filesystem
creation could fail in cases where the calculated target partition
size was too small to contain the filesystem created using mkfs.  This
occurred in particular when creating partitions to contain very large
filesystems such as those containing sdk image artifacts.

This same limition is present in the oe-core image creation classes,
which can be readily see by changing IMAGE_OVERHEAD_FACTOR from the
default 1.3 to 1.0 and building a sato-sdk image.

It should be possible to calculate required sizes exactly given the
source rootfs and target filesystem types, but for now, to address the
specific problem users are hitting in such situations, we'll just do
exactly what oe-core does and define and use an IMAGE_OVERHEAD_FACTOR
or 1.3 in those cases.

Fixes [YOCTO #6863].

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/scripts/lib/wic/utils/oe/misc.py b/scripts/lib/wic/utils/oe/misc.py
index aa9b23582b..b0b5baab73 100644
--- a/scripts/lib/wic/utils/oe/misc.py
+++ b/scripts/lib/wic/utils/oe/misc.py
@@ -123,6 +123,7 @@ def add_wks_var(key, val):
 
 BOOTDD_EXTRA_SPACE = 16384
 IMAGE_EXTRA_SPACE = 10240
+IMAGE_OVERHEAD_FACTOR = 1.3
 
 __bitbake_env_lines = ""