Return-Path: Received: from mx62.netapp.com ([216.240.31.182]:7038 "EHLO mx62.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751304AbcIGU5g (ORCPT ); Wed, 7 Sep 2016 16:57:36 -0400 Subject: Re: [PATCH Version 9 RESEND 04/12] NFS detect session trunking To: , References: <1472744693-124241-1-git-send-email-andros@netapp.com> <1472744693-124241-5-git-send-email-andros@netapp.com> CC: From: Anna Schumaker Message-ID: Date: Wed, 7 Sep 2016 16:47:48 -0400 MIME-Version: 1.0 In-Reply-To: <1472744693-124241-5-git-send-email-andros@netapp.com> Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Hi Andy, On 09/01/2016 11:44 AM, andros@netapp.com wrote: > From: Andy Adamson > > Signed-off-by: Andy Adamson > --- > fs/nfs/nfs4_fs.h | 2 ++ > fs/nfs/nfs4client.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 95 insertions(+) > > diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h > index 4be567a..eb315e1 100644 > --- a/fs/nfs/nfs4_fs.h > +++ b/fs/nfs/nfs4_fs.h > @@ -277,6 +277,8 @@ extern int nfs4_proc_get_lease_time(struct nfs_client *clp, > struct nfs_fsinfo *fsinfo); > extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data, > bool sync); > +extern int nfs4_detect_session_trunking(struct nfs_client *clp, > + struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt); > > static inline bool > is_ds_only_client(struct nfs_client *clp) > diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c > index f356d50..4e15ae1 100644 > --- a/fs/nfs/nfs4client.c > +++ b/fs/nfs/nfs4client.c > @@ -595,6 +595,99 @@ out_major_mismatch: > return false; > } > > +/* > + * Returns true if server minor ids match > + */ > +static bool > +nfs4_check_serverowner_minor_id(struct nfs41_server_owner *o1, > + struct nfs41_server_owner *o2) > +{ > + /* Check eir_server_owner so_minor_id */ > + if (o1->minor_id != o2->minor_id) > + goto out_minor_mismatch; > + > + dprintk("NFS: --> %s server owner minor IDs match\n", __func__); > + return true; > + > +out_minor_mismatch: > + dprintk("NFS: --> %s server owner minor IDs do not match\n", __func__); > + return false; > +} > + > +/* > + * Returns true if the server scopes match > + */ > +static bool > +nfs4_check_server_scope(struct nfs41_server_scope *s1, > + struct nfs41_server_scope *s2) > +{ > + if (s1->server_scope_sz != s2->server_scope_sz) > + goto out_scope_mismatch; > + if (memcmp(s1->server_scope, s2->server_scope, > + s1->server_scope_sz) != 0) > + goto out_scope_mismatch; > + > + dprintk("NFS: --> %s server scopes match\n", __func__); > + return true; > + > +out_scope_mismatch: > + dprintk("NFS: --> %s server scopes do not match\n", > + __func__); > + return false; > +} > + > +/** > + * nfs4_detect_session_trunking - Checks for session trunking called > + * after a successful EXCHANGE_ID testing a multi-addr connection to be > + * potentially added as a session trunk > + * > + * @clp: original mount nfs_client > + * @res: result structure from an exchange_id using the original mount > + * nfs_client with a new multi_addr transport > + * > + * Returns zero on success, otherwise -EINVAL > + * > + * Note: since the exchange_id for the new multi_addr transport uses the > + * same nfs_client from the original mount, the cl_owner_id is reused, > + * so eir_clientowner is the same. > + */ > +int nfs4_detect_session_trunking(struct nfs_client *clp, > + struct nfs41_exchange_id_res *res, > + struct rpc_xprt *xprt) > +{ > + int status = -EINVAL; > + /* Check eir_clientid */ > + if (!nfs4_match_clientids(clp->cl_clientid, res->clientid)) > + goto out; > + > + /* Check eir_server_owner so_major_id */ > + if (!nfs4_check_serverowner_major_id(clp->cl_serverowner, > + res->server_owner)) > + goto out; > + > + /* Check eir_server_owner so_minor_id */ > + if (!nfs4_check_serverowner_minor_id(clp->cl_serverowner, > + res->server_owner)) > + goto out; > + > + /* Check eir_server_scope */ > + if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope)) > + goto out; > + > + status = 0; > +out: > + if (status) > + pr_info("NFS: %s: Session trunking failed for %s status %d\n", > + clp->cl_hostname, > + xprt->address_strings[RPC_DISPLAY_ADDR], status); > + else > + pr_info("NFS: %s: Session trunking succeeded for %s\n", > + clp->cl_hostname, > + xprt->address_strings[RPC_DISPLAY_ADDR]); I'm not a fan of the if/else status check here. I think it might be cleaner if you match the style of nfs4_check_server_scope() and create an out_err label that prints the failed message and returns -EINVAL directly. Then you can get rid of the "status" variable all together and avoid the if/else check at the end. Thanks, Anna > + > + return status; > +} > + > /** > * nfs41_walk_client_list - Find nfs_client that matches a client/server owner > * >