[PATCH 0/1] Signal to disallow open of a dm device

[Daniil Lunev <dlunev@chromium.org>]

There was a previuous discussion upstream about this kind of
functionality (see https://lkml.org/lkml/2022/1/24/633). The previous
patchset was rejected with concerns about how the feature was
integrated. This patch takes a different approach, and instead of
tying itself to unrelated mechanisms (e.g. deffer remove), this one
allows an explicit signal via message interface to signalize device
mapper shall block any further access to the device. The primary use
case is to restrict userspace access to decrypted data after a device
was setup with a kernel facility (e.g. swap).


Daniil Lunev (1):
  dm: add message command to disallow device open

 drivers/md/dm-core.h          |  1 +
 drivers/md/dm-ioctl.c         | 10 ++++++++++
 drivers/md/dm.c               | 12 ++++++++++++
 drivers/md/dm.h               | 10 ++++++++++
 include/uapi/linux/dm-ioctl.h |  5 +++++
 5 files changed, 38 insertions(+)

-- 
2.31.0