Re: [PATCH v6 1/2] net/handshake: Create a NETLINK service for handling handshake requests

Chuck Lever III
2023-03-04T17:44:49Z

> On Mar 4, 2023, at 12:25 PM, Chuck Lever III <chuck.lever@oracle.com> wrote:
>
>
>
>> On Mar 3, 2023, at 9:21 PM, Jakub Kicinski <kuba@kernel.org> wrote:
>>
>> On Fri, 03 Mar 2023 13:51:31 -0500 Chuck Lever wrote:
>>
>>> +static const struct genl_split_ops handshake_nl_ops[] = {
>>> + {
>>> + .cmd = HANDSHAKE_CMD_ACCEPT,
>>> + .doit = handshake_nl_accept_doit,
>>> + .policy = handshake_accept_nl_policy,
>>> + .maxattr = HANDSHAKE_A_ACCEPT_HANDLER_CLASS,
>>> + .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
>>> + },
>>> + {
>>> + .cmd = HANDSHAKE_CMD_DONE,
>>> + .doit = handshake_nl_done_doit,
>>> + .policy = handshake_done_nl_policy,
>>> + .maxattr = HANDSHAKE_A_DONE_MAX,
>>> + .flags = GENL_CMD_CAP_DO,
>>> + },
>>> +};
>>> +
>>> +static const struct genl_multicast_group handshake_nl_mcgrps[] = {
>>> + [HANDSHAKE_HANDLER_CLASS_NONE] = { .name = HANDSHAKE_MCGRP_NONE, },
>>> +};
>>> +
>>> +static struct genl_family __ro_after_init handshake_genl_family = {
>>> + .hdrsize = 0,
>>> + .name = HANDSHAKE_FAMILY_NAME,
>>> + .version = HANDSHAKE_FAMILY_VERSION,
>>> + .netnsok = true,
>>> + .parallel_ops = true,
>>> + .n_mcgrps = ARRAY_SIZE(handshake_nl_mcgrps),
>>> + .n_split_ops = ARRAY_SIZE(handshake_nl_ops),
>>> + .split_ops = handshake_nl_ops,
>>> + .mcgrps = handshake_nl_mcgrps,
>>> + .module = THIS_MODULE,
>>> +};
>>
>> You're not auto-generating the family, ops, and policies?
>> Any reason?
>
> I couldn't find a way to have the generated source appear
> in the middle of a source file. But I see that's not the
> way others are doing it, so I have added separate files
> under net/handshake for the generated source and header
> material. Two things, though:
>
> 1. I don't see a generated struct genl_family.

Some experimentation revealed that this is because the spec
was a "genetlink-c" spec which prevents the generation of
"struct genl_family".

But switching it to a "genetlink" spec means it wants my
main header to be linux/handshake.h, and it won't allow the
use of "uapi-header" to put that header somewhere else (in
my case, I thought linux/net/handshake.h was more appropriate).

> 2. The SPDX tags in the generated source files is "BSD
> 3-clause", but the tag in my spec is "GPL-2.0 with
> syscall note". Oddly, the generated uapi header still
> has the latter (correct) tag.
>
> --
> Chuck Lever
>
>

--
Chuck Lever