> On Sep 22, 2023, at 3:25 PM, Lorenzo Bianconi <lorenzo.bianconi@xxxxxxxxxx> wrote: > >> >> >>> On Sep 22, 2023, at 12:20 PM, Lorenzo Bianconi <lorenzo.bianconi@xxxxxxxxxx> wrote: >>> >>>> On Fri, 2023-09-22 at 14:44 +0200, Lorenzo Bianconi wrote: >>>>> Introduce write_threads and write_v4_end_grace netlink commands similar >>>>> to the ones available through the procfs. >>>>> Introduce nfsd_nl_server_status_get_dumpit netlink command in order to >>>>> report global server metadata. >>>>> >>>>> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> >>>>> --- >>>>> This patch can be tested with user-space tool reported below: >>>>> https://github.com/LorenzoBianconi/nfsd-netlink.git >>>>> --- >>>>> Documentation/netlink/specs/nfsd.yaml | 33 +++++++++ >>>>> fs/nfsd/netlink.c | 30 ++++++++ >>>>> fs/nfsd/netlink.h | 5 ++ >>>>> fs/nfsd/nfsctl.c | 98 +++++++++++++++++++++++++++ >>>>> include/uapi/linux/nfsd_netlink.h | 11 +++ >>>>> 5 files changed, 177 insertions(+) >>>>> >>>>> diff --git a/Documentation/netlink/specs/nfsd.yaml b/Documentation/netlink/specs/nfsd.yaml >>>>> index 403d3e3a04f3..fa1204892703 100644 >>>>> --- a/Documentation/netlink/specs/nfsd.yaml >>>>> +++ b/Documentation/netlink/specs/nfsd.yaml >>>>> @@ -62,6 +62,15 @@ attribute-sets: >>>>> name: compound-ops >>>>> type: u32 >>>>> multi-attr: true >>>>> + - >>>>> + name: server-attr >>>>> + attributes: >>>>> + - >>>>> + name: threads >>>>> + type: u16 >>>> >>>> 65k threads ought to be enough for anybody! >>> >>> maybe u8 is fine here :) >> >> 32-bit is the usual for this kind of interface. I don't think we need to go with 16-bit. > > ack, fine > >> >> >>>>> + - >>>>> + name: v4-grace >>>>> + type: u8 >>>>> >>>>> operations: >>>>> list: >>>>> @@ -72,3 +81,27 @@ operations: >>>>> dump: >>>>> pre: nfsd-nl-rpc-status-get-start >>>>> post: nfsd-nl-rpc-status-get-done >>>>> + - >>>>> + name: threads-set >>>>> + doc: set the number of running threads >>>>> + attribute-set: server-attr >>>>> + flags: [ admin-perm ] > > [...] > >>> >>> I am not sure if ynl supports a doit operation with a request with no parameters. >>> @Chuck, Jakub: any input here? >> >> I think it does, I might have done something like that for one of the >> handshake protocol commands. > > please correct me if I am wrong but in Documentation/netlink/specs/handshake.yaml > we have accept and done operations and both of them have some parameters in the > request field, right? I was probably thinking of a command that did not make it into the final upstream version of handshake. >> But I think Jeff's right, end_grace might be better postponed. Pick any of >> the others that you think might be easy to implement instead. > > ack, fine. Do you agree to have a global container (server-status-get) for all > the server metadata instead of adding dedicated get APIs? At this point I would like to have a distinct command for each data item. > Regards, > Lorenzo > >> >> >>> Regards, >>> Lorenzo >>> >>>> >>>>> + return 0; >>>>> +#else >>>>> + return -EOPNOTSUPP; >>>>> +#endif /* CONFIG_NFSD_V4 */ >>>>> +} >>>>> + >>>>> +/** >>>>> + * nfsd_nl_server_status_get_start - Prepare server_status_get dumpit >>>>> + * @cb: netlink metadata and command arguments >>>>> + * >>>>> + * Return values: >>>>> + * %0: The server_status_get command may proceed >>>>> + * %-ENODEV: There is no NFSD running in this namespace >>>>> + */ >>>>> +int nfsd_nl_server_status_get_start(struct netlink_callback *cb) >>>>> +{ >>>>> + struct nfsd_net *nn = net_generic(sock_net(cb->skb->sk), nfsd_net_id); >>>>> + >>>>> + return nn->nfsd_serv ? 0 : -ENODEV; >>>>> +} >>>>> + >>>>> +/** >>>>> + * nfsd_nl_server_status_get_dumpit - dump server status info >>>>> + * @skb: reply buffer >>>>> + * @cb: netlink metadata and command arguments >>>>> + * >>>>> + * Returns the size of the reply or a negative errno. >>>>> + */ >>>>> +int nfsd_nl_server_status_get_dumpit(struct sk_buff *skb, >>>>> + struct netlink_callback *cb) >>>>> +{ >>>>> + struct net *net = sock_net(skb->sk); >>>>> +#ifdef CONFIG_NFSD_V4 >>>>> + struct nfsd_net *nn = net_generic(net, nfsd_net_id); >>>>> +#endif /* CONFIG_NFSD_V4 */ >>>>> + void *hdr; >>>>> + >>>>> + if (cb->args[0]) /* already consumed */ >>>>> + return 0; >>>>> + >>>>> + hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, >>>>> + &nfsd_nl_family, NLM_F_MULTI, >>>>> + NFSD_CMD_SERVER_STATUS_GET); >>>>> + if (!hdr) >>>>> + return -ENOBUFS; >>>>> + >>>>> + if (nla_put_u16(skb, NFSD_A_SERVER_ATTR_THREADS, nfsd_nrthreads(net))) >>>>> + return -ENOBUFS; >>>>> +#ifdef CONFIG_NFSD_V4 >>>>> + if (nla_put_u8(skb, NFSD_A_SERVER_ATTR_V4_GRACE, !nn->grace_ended)) >>>>> + return -ENOBUFS; >>>>> +#endif /* CONFIG_NFSD_V4 */ >>>>> + >>>>> + genlmsg_end(skb, hdr); >>>>> + cb->args[0] = 1; >>>>> + >>>>> + return skb->len; >>>>> +} >>>>> + >>>>> /** >>>>> * nfsd_net_init - Prepare the nfsd_net portion of a new net namespace >>>>> * @net: a freshly-created network namespace >>>>> diff --git a/include/uapi/linux/nfsd_netlink.h b/include/uapi/linux/nfsd_netlink.h >>>>> index c8ae72466ee6..b82fbc53d336 100644 >>>>> --- a/include/uapi/linux/nfsd_netlink.h >>>>> +++ b/include/uapi/linux/nfsd_netlink.h >>>>> @@ -29,8 +29,19 @@ enum { >>>>> NFSD_A_RPC_STATUS_MAX = (__NFSD_A_RPC_STATUS_MAX - 1) >>>>> }; >>>>> >>>>> +enum { >>>>> + NFSD_A_SERVER_ATTR_THREADS = 1, >>>>> + NFSD_A_SERVER_ATTR_V4_GRACE, >>>>> + >>>>> + __NFSD_A_SERVER_ATTR_MAX, >>>>> + NFSD_A_SERVER_ATTR_MAX = (__NFSD_A_SERVER_ATTR_MAX - 1) >>>>> +}; >>>>> + >>>>> enum { >>>>> NFSD_CMD_RPC_STATUS_GET = 1, >>>>> + NFSD_CMD_THREADS_SET, >>>>> + NFSD_CMD_V4_GRACE_RELEASE, >>>>> + NFSD_CMD_SERVER_STATUS_GET, >>>>> >>>>> __NFSD_CMD_MAX, >>>>> NFSD_CMD_MAX = (__NFSD_CMD_MAX - 1) >>>> >>>> -- >>>> Jeff Layton <jlayton@xxxxxxxxxx> >>>> >> >> -- >> Chuck Lever -- Chuck Lever
