Merge branch 'flower-rework-tca_flower_key_enc_flags-usage'

Merge branch 'flower-rework-tca_flower_key_enc_flags-usage'

Asbjørn Sloth Tønnesen says:

====================
flower: rework TCA_FLOWER_KEY_ENC_FLAGS usage

This series reworks the recently added TCA_FLOWER_KEY_ENC_FLAGS
attribute, to be more like TCA_FLOWER_KEY_FLAGS, and use the unused
u32 flags field in FLOW_DISSECTOR_KEY_ENC_CONTROL, instead of adding
a new flags field as FLOW_DISSECTOR_KEY_ENC_FLAGS.

I have defined the new FLOW_DIS_F_* and TCA_FLOWER_KEY_FLAGS_*
flags to co-exist with the existing flags, so the meaning
of the flags field in struct flow_dissector_key_control is not
depending on the context it is used in. If we run out of bits
then we can always split them up later, if we really want to.
Future flags might also be valid in both contexts.

iproute2 RFC v2 patch:
https://lore.kernel.org/560bcd549ca8ab24b1ad5abe352580a621f6d426.1720790774.git.dcaratti@redhat.com/

v3: https://lore.kernel.org/20240709163825.1210046-1-ast@fiberby.net/
v2: https://lore.kernel.org/20240705133348.728901-1-ast@fiberby.net/
v1: https://lore.kernel.org/20240703104600.455125-1-ast@fiberby.net/
RFC: https://lore.kernel.org/20240611235355.177667-1-ast@fiberby.net/
====================

Link: https://patch.msgid.link/20240713021911.1631517-1-ast@fiberby.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>