[PATCH 0/4] configfs: implement committable items and add sample code

Bartosz Golaszewski
2020-11-25T15:24:15Z

Committable items in configfs are well defined and documented but unfortunately
so far never implemented.

The use-case we have over at the GPIO subsystem is using configfs in
conjunction with sysfs to replace our current gpio-mockup testing module
with one that will be much more flexible and will allow complete coverage
of the GPIO uAPI.

The current gpio-mockup module is controlled using module parameters which
forces the user to reload it everytime they need to change the chip
configuration or layout and makes it difficult to extend its functionality.

Testing module based on configfs would allow fine-grained control over dummy
GPIO chips but since GPIO devices must be configured before they are
instantiated, we need committable items.

This implements them and adds code examples to configfs_sample module. The
first two patches are just cosmetic.

Bartosz Golaszewski (4):
configfs: increase the item name length
configfs: use BIT() for internal flags
configfs: implement committable items
samples: configfs: add a committable group

Documentation/filesystems/configfs.rst | 6 +-
fs/configfs/configfs_internal.h | 22 +--
fs/configfs/dir.c | 239 ++++++++++++++++++++++++-
fs/configfs/file.c | 8 +
include/linux/configfs.h | 3 +-
samples/configfs/configfs_sample.c | 150 ++++++++++++++++
6 files changed, 408 insertions(+), 20 deletions(-)

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2.29.1