ABI and API Deprecation

This document details the policy for maintaining stability of SPDK ABI and API.

Major ABI version can change at most once for each SPDK release. ABI versions are managed separately for each library and follow Semantic Versioning.

API and ABI deprecation notices shall be posted in the next section. Each entry must describe what will be removed and can suggest the future use or alternative. Specific future SPDK release for the removal must be provided. ABI cannot be removed without providing deprecation notice for at least single SPDK release.

Deprecated code paths must be registered with SPDK_LOG_DEPRECATION_REGISTER() and logged with SPDK_LOG_DEPRECATED(). The tag used with these macros will appear in the SPDK log at the warn level when SPDK_LOG_DEPRECATED() is called, subject to rate limits. The tags can be matched with the level 4 headers below.

Deprecation Notices

util/net

spdk_net_getaddr

Returning -1 and setting errno on this function is deprecated and will be changed in the 26.01 release. This function will return negative errno values instead.

sock

spdk_sock_\*

spdk_sock_getaddr, spdk_sock_close, spdk_sock_flush, spdk_sock_recv, spdk_sock_writev, spdk_sock_readv, spdk_sock_recv_next, spdk_sock_set_recvlowat, spdk_sock_set_recvbuf, spdk_sock_set_sendbuf, spdk_sock_group_add_sock, spdk_sock_group_remove_sock, spdk_sock_group_provide_buf, spdk_sock_group_poll, spdk_sock_group_poll_count, spdk_sock_group_close, spdk_sock_impl_get_opts, spdk_sock_impl_set_opts, spdk_sock_set_default_impl, spdk_sock_group_register_interrupt

Returning -1 and setting errno on these functions is deprecated and will be changed in the 26.01 release. These functions will return negative errno values instead.

gpt

old_gpt_guid

Deprecated the SPDK partition type GUID 7c5222bd-8f5d-4087-9c00-bf9843c7b58c. Partitions of this type have bdevs created that are one block less than the actual size of the partition. Existing partitions using the deprecated GUID can continue to use that GUID; support for the deprecated GUID will remain in SPDK indefinitely, and will continue to exhibit the off-by-one bug so that on-disk metadata layouts based on the incorrect size are not affected.

See GitHub issue 2801 for additional details on the bug.

New SPDK partition types should use GUID 6527994e-2c5a-4eec-9613-8f5944074e8b which will create a bdev of the correct size.