This series evolved around the idea of introducing a new env_op type to control (and possibly restrict) the export of variables. This is especially useful if one wants to prevent dynamic configuration information from ending up in a saved environment - the 'classic' example being network setup with "dhcp" followed by the "saveenv" command.
(The networking case is even further complicated by the fact that users may actually wish to setup and save a static IP configuration manually, which means that "locking up" the corresponding variables right away isn't a viable solution.)
See also: http://lists.denx.de/pipermail/u-boot/2015-September/227611.html http://lists.denx.de/pipermail/u-boot/2016-April/250237.html Pointed out by Joe Hershberger: http://lists.denx.de/pipermail/u-boot/2010-May/071315.html http://lists.denx.de/pipermail/u-boot/2010-June/073031.html
Regards, B. Nortmann
Changes in v2: - Add "Reviewed-by" sjg - Removed too narrow (flag & H_FORCE) expression, use "flag" directly - Fixed outdated "env_flags_varaccess_lock" to the correct "env_flags_varaccess_system"
Bernhard Nortmann (7): env: Allow unconditional access if H_PROGRAMMATIC is set net: dm: Ignore unknown env_op_* constants env: Introduce "export" operation and (access flag) restriction env: Introduce "transient" and "system" access flags sunxi: env: flag fel_* environment vars as "system" env: Introduce setenv_transient() helper function env: Automatically mark dynamic configuration info as "do not export"
cmd/net.c | 34 +++++++++++++++++----------------- cmd/nvedit.c | 24 +++++++++++++++++++++++- common/env_flags.c | 21 ++++++++++++++++++--- include/common.h | 1 + include/configs/sunxi-common.h | 8 ++++++++ include/env_flags.h | 5 ++++- include/search.h | 1 + lib/hashtable.c | 3 +++ net/eth-uclass.c | 2 ++ 9 files changed, 77 insertions(+), 22 deletions(-)