config: add support for loading profiles

This patch adds --profile arg to lvm cmds and adds config/profile_dir
configuration setting to select the directory where profiles are stored
By default it's /etc/lvm/profile.

The profiles are added by using new "add_profile" fn and then loaded
using the "load_profile" fn. All profiles are stored in a cmd context
within the new "struct profile_params":

struct profile_params {
  const char *dir;
  struct profile *global_profile;
  struct dm_list profiles_to_load;
  struct dm_list profiles;
};

...where "dir" is the directory with profiles, "global_profile" is
the profile that is set globally via the --profile arg (IOW, not
set per VG/LV basis based on metadata record) and the "profiles"
is the list with loaded profiles.

1 files changed, 3 insertions, 0 deletions

diff --git a/doc/example.conf.in b/doc/example.conf.in
index 162072178..3bc8c3cbf 100644
--- a/doc/example.conf.in
+++ b/doc/example.conf.in
@@ -23,6 +23,9 @@ config {
 
     # If enabled, any configuration mismatch aborts the LVM2 process.
     abort_on_errors = 0
+
+    # Directory where LVM looks for configuration profiles.
+    profile_dir = "@DEFAULT_SYS_DIR@/@DEFAULT_PROFILE_SUBDIR"
 }
 
 # This section allows you to configure which block devices should