data_ro means that write, write_zeroes and unmap operations are not
allowed.
md_ro means that resize, set_xattr and remove_xattr are not
allowed.
There is no code yet that can activate this - it is coming in a future
patch. Two usages are planned though:
1) a user explicitly marks a blob as read-only - this is persisted so that
future loads of the blob will ensure the blob cannot be modified - neither
metadata nor data
2) a future feature flag framework (how's that for alliteration) may allow
a blob to be opened, but not allow metadata modifications, if there are
feature flags set in the blob's or blobstore's metadata that the
application does not understand
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I247fd900430c56f7176edfb80dddd5a1a6c8dc87
Reviewed-on: https://review.gerrithub.io/388663
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
f2223d7d21