From: Benny Halevy Subject: Re: [PATCH v2 16/47] nfsd41: match clientid establishment method Date: Tue, 31 Mar 2009 09:59:17 +0300 Message-ID: <49D1BF45.4080104@panasas.com> References: <49CDDFC2.4070402@panasas.com> <1238229137-10764-1-git-send-email-bhalevy@panasas.com> <20090330220725.GO31237@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: linux-nfs@vger.kernel.org, pnfs@linux-nfs.org To: "J. Bruce Fields" Return-path: Received: from gw-ca.panasas.com ([209.116.51.66]:28468 "EHLO laguna.int.panasas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754182AbZCaHA5 (ORCPT ); Tue, 31 Mar 2009 03:00:57 -0400 In-Reply-To: <20090330220725.GO31237@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mar. 31, 2009, 1:07 +0300, "J. Bruce Fields" wrote: > On Sat, Mar 28, 2009 at 11:32:17AM +0300, Benny Halevy wrote: >> From: Andy Adamson >> >> We need to distinguish between client names provided by NFSv4.0 clients >> SETCLIENTID and those provided by NFSv4.1 via EXCHANGE_ID when looking >> up the clientid by string. >> >> Signed-off-by: Benny Halevy >> Signed-off-by: Andy Adamson >> [nfsd41: use boolean values for use_exchange_id argument] >> Signed-off-by: Benny Halevy >> --- >> fs/nfsd/nfs4recover.c | 3 ++- >> fs/nfsd/nfs4state.c | 41 ++++++++++++++++++++++++++++++----------- >> include/linux/nfsd/state.h | 2 +- >> 3 files changed, 33 insertions(+), 13 deletions(-) >> >> diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c >> index b11cf8d..3444c00 100644 >> --- a/fs/nfsd/nfs4recover.c >> +++ b/fs/nfsd/nfs4recover.c >> @@ -344,7 +344,8 @@ purge_old(struct dentry *parent, struct dentry *child) >> { >> int status; >> >> - if (nfs4_has_reclaimed_state(child->d_name.name)) >> + /* note: we currently use this path only for minorversion 0 */ >> + if (nfs4_has_reclaimed_state(child->d_name.name, false)) >> return 0; >> >> status = nfsd4_clear_clid_dir(parent, child); >> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >> index 09c63ff..0c39376 100644 >> --- a/fs/nfsd/nfs4state.c >> +++ b/fs/nfsd/nfs4state.c >> @@ -723,25 +723,44 @@ find_unconfirmed_client(clientid_t *clid) >> return NULL; >> } >> >> +/* >> + * Return 1 iff clp's clientid establishment method matches the use_exchange_id >> + * parameter. Matching is based on the fact the at least one of the >> + * EXCHGID4_FLAG_USE_{NON_PNFS,PNFS_MDS,PNFS_DS} flags must be set for v4.1 >> + */ >> +static inline int >> +match_clientid_establishment(struct nfs4_client *clp, bool use_exchange_id) >> +{ >> +#if defined(CONFIG_NFSD_V4_1) >> + return (clp->cl_exchange_flags != 0) == (use_exchange_id != false); > > This seems a bit baroque; the "!= false" is a no-op, for one thing, > isn't it? The idea is to efficiently do explicit boolean comparison. Without the "!= false" the comparison will fail for 1 != use_exchange_id != 0. Does this make it any clearer: if (use_exchange_flags) return clp->cl_exchange_flags != 0; return clp->cl_exchange_flags == 0; or maybe bool has_exchange_flags = (clp->cl_exchange_flags != 0); if (use_exchange_flags) return has_exchange_flags; return !has_exchange_flags; or a long boolean expression return ((clp->cl_exchange_flags && use_exchange_id) || (!clp->cl_exchange_flags && !use_exchange_id)) Benny > > --b. > >> +#else /* CONFIG_NFSD_V4_1 */ >> + return 1; >> +#endif /* CONFIG_NFSD_V4_1 */ >> +} >> + >> static struct nfs4_client * >> -find_confirmed_client_by_str(const char *dname, unsigned int hashval) >> +find_confirmed_client_by_str(const char *dname, unsigned int hashval, >> + bool use_exchange_id) >> { >> struct nfs4_client *clp; >> >> list_for_each_entry(clp, &conf_str_hashtbl[hashval], cl_strhash) { >> - if (same_name(clp->cl_recdir, dname)) >> + if (same_name(clp->cl_recdir, dname) && >> + match_clientid_establishment(clp, use_exchange_id)) >> return clp; >> } >> return NULL; >> } >> >> static struct nfs4_client * >> -find_unconfirmed_client_by_str(const char *dname, unsigned int hashval) >> +find_unconfirmed_client_by_str(const char *dname, unsigned int hashval, >> + bool use_exchange_id) >> { >> struct nfs4_client *clp; >> >> list_for_each_entry(clp, &unconf_str_hashtbl[hashval], cl_strhash) { >> - if (same_name(clp->cl_recdir, dname)) >> + if (same_name(clp->cl_recdir, dname) && >> + match_clientid_establishment(clp, use_exchange_id)) >> return clp; >> } >> return NULL; >> @@ -895,7 +914,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, >> nfs4_lock_state(); >> status = nfs_ok; >> >> - conf = find_confirmed_client_by_str(dname, strhashval); >> + conf = find_confirmed_client_by_str(dname, strhashval, true); >> if (conf) { >> if (!same_verf(&verf, &conf->cl_verifier)) { >> /* 18.35.4 case 8 */ >> @@ -943,7 +962,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, >> } >> } >> >> - unconf = find_unconfirmed_client_by_str(dname, strhashval); >> + unconf = find_unconfirmed_client_by_str(dname, strhashval, true); >> if (unconf) { >> /* >> * Possible retry or client restart. Per 18.35.4 case 4, >> @@ -1041,7 +1060,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, >> strhashval = clientstr_hashval(dname); >> >> nfs4_lock_state(); >> - conf = find_confirmed_client_by_str(dname, strhashval); >> + conf = find_confirmed_client_by_str(dname, strhashval, false); >> if (conf) { >> /* RFC 3530 14.2.33 CASE 0: */ >> status = nfserr_clid_inuse; >> @@ -1056,7 +1075,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, >> * has a description of SETCLIENTID request processing consisting >> * of 5 bullet points, labeled as CASE0 - CASE4 below. >> */ >> - unconf = find_unconfirmed_client_by_str(dname, strhashval); >> + unconf = find_unconfirmed_client_by_str(dname, strhashval, false); >> status = nfserr_resource; >> if (!conf) { >> /* >> @@ -1211,7 +1230,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, >> unsigned int hash = >> clientstr_hashval(unconf->cl_recdir); >> conf = find_confirmed_client_by_str(unconf->cl_recdir, >> - hash); >> + hash, false); >> if (conf) { >> nfsd4_remove_clid_dir(conf); >> expire_client(conf); >> @@ -3332,12 +3351,12 @@ alloc_reclaim(void) >> } >> >> int >> -nfs4_has_reclaimed_state(const char *name) >> +nfs4_has_reclaimed_state(const char *name, bool use_exchange_id) >> { >> unsigned int strhashval = clientstr_hashval(name); >> struct nfs4_client *clp; >> >> - clp = find_confirmed_client_by_str(name, strhashval); >> + clp = find_confirmed_client_by_str(name, strhashval, use_exchange_id); >> return clp ? 1 : 0; >> } >> >> diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h >> index 5de36a7..feab6ec 100644 >> --- a/include/linux/nfsd/state.h >> +++ b/include/linux/nfsd/state.h >> @@ -331,7 +331,7 @@ extern void nfsd4_init_recdir(char *recdir_name); >> extern int nfsd4_recdir_load(void); >> extern void nfsd4_shutdown_recdir(void); >> extern int nfs4_client_to_reclaim(const char *name); >> -extern int nfs4_has_reclaimed_state(const char *name); >> +extern int nfs4_has_reclaimed_state(const char *name, bool use_exchange_id); >> extern void nfsd4_recdir_purge_old(void); >> extern int nfsd4_create_clid_dir(struct nfs4_client *clp); >> extern void nfsd4_remove_clid_dir(struct nfs4_client *clp); >> -- >> 1.6.2.1 >>