From: Mi Jinlong Subject: [PATCH] NLM: add network test when host expire but hold lock at nlm_gc_hosts Date: Wed, 02 Dec 2009 17:47:04 +0800 Message-ID: <4B163798.7010309@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 To: NFSv3 list , "Trond.Myklebust" , "J. Bruce Fields" Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:57966 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750927AbZLBJpU (ORCPT ); Wed, 2 Dec 2009 04:45:20 -0500 Sender: linux-nfs-owner@vger.kernel.org List-ID: After a client get lock, it's network partition for some reasons. other client cannot get lock success forever. This patch can avoid this problem using rpc_ping to test client's network when host expired but hold lock. If the client's network is partition, server will release client's lock, other client will get lock success. Signed-off-by: mijinlong@cn.fujitsu.com --- fs/lockd/host.c | 54 ++++++++++++++++++++++++++++++++++++++++++- include/linux/sunrpc/clnt.h | 1 + net/sunrpc/clnt.c | 4 +- 3 files changed, 56 insertions(+), 3 deletions(-) diff --git a/fs/lockd/host.c b/fs/lockd/host.c index 4600c20..73f6732 100644 --- a/fs/lockd/host.c +++ b/fs/lockd/host.c @@ -31,6 +31,7 @@ static int nrhosts; static DEFINE_MUTEX(nlm_host_mutex); static void nlm_gc_hosts(void); +static int nlm_test_host(struct nlm_host *); struct nlm_lookup_host_info { const int server; /* search for server|client */ @@ -550,13 +551,24 @@ nlm_gc_hosts(void) for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) { hlist_for_each_entry_safe(host, pos, next, chain, h_hash) { - if (atomic_read(&host->h_count) || host->h_inuse + if (atomic_read(&host->h_count) || time_before(jiffies, host->h_expires)) { dprintk("nlm_gc_hosts skipping %s (cnt %d use %d exp %ld)\n", host->h_name, atomic_read(&host->h_count), host->h_inuse, host->h_expires); continue; } + + if (host->h_inuse) { + if (!nlm_test_host(host)) { + dprintk("nlm_gc_hosts skipping %s (cnt %d use %d exp %ld)\n", + host->h_name, atomic_read(&host->h_count), + host->h_inuse, host->h_expires); + continue; + } + nlmsvc_free_host_resources(host); + } + dprintk("lockd: delete host %s\n", host->h_name); hlist_del_init(&host->h_hash); @@ -567,3 +579,43 @@ nlm_gc_hosts(void) next_gc = jiffies + NLM_HOST_COLLECT; } + +static int +nlm_test_host(struct nlm_host *host) +{ + struct rpc_clnt *clnt; + + dprintk("lockd: test host %s\n", host->h_name); + clnt = host->h_rpcclnt; + if (clnt == NULL) { + unsigned long increment = HZ; + struct rpc_timeout timeparms = { + .to_initval = increment, + .to_increment = increment, + .to_maxval = increment * 3UL, + .to_retries = 2U, + }; + + struct rpc_create_args args = { + .protocol = host->h_proto, + .address = nlm_addr(host), + .addrsize = host->h_addrlen, + .saddress = nlm_srcaddr(host), + .timeout = &timeparms, + .servername = host->h_name, + .program = &nlm_program, + .version = host->h_version, + .authflavor = RPC_AUTH_UNIX, + .flags = RPC_CLNT_CREATE_AUTOBIND, + }; + + clnt = rpc_create(&args); + if (IS_ERR(clnt)) + return -EIO; + + rpc_shutdown_client(clnt); + return 0; + } + + return rpc_ping(clnt, RPC_TASK_SOFT); +} diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h index 8ed9642..b221f8f 100644 --- a/include/linux/sunrpc/clnt.h +++ b/include/linux/sunrpc/clnt.h @@ -162,6 +162,7 @@ size_t rpc_pton(const char *, const size_t, char * rpc_sockaddr2uaddr(const struct sockaddr *); size_t rpc_uaddr2sockaddr(const char *, const size_t, struct sockaddr *, const size_t); +int rpc_ping(struct rpc_clnt *clnt, int flags); static inline unsigned short rpc_get_port(const struct sockaddr *sap) { diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 38829e2..53b9f34 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -79,7 +79,6 @@ static void call_connect_status(struct rpc_task *task); static __be32 *rpc_encode_header(struct rpc_task *task); static __be32 *rpc_verify_header(struct rpc_task *task); -static int rpc_ping(struct rpc_clnt *clnt, int flags); static void rpc_register_client(struct rpc_clnt *clnt) { @@ -1675,7 +1674,7 @@ static struct rpc_procinfo rpcproc_null = { .p_decode = rpcproc_decode_null, }; -static int rpc_ping(struct rpc_clnt *clnt, int flags) +int rpc_ping(struct rpc_clnt *clnt, int flags) { struct rpc_message msg = { .rpc_proc = &rpcproc_null, @@ -1686,6 +1685,7 @@ static int rpc_ping(struct rpc_clnt *clnt, int flags) put_rpccred(msg.rpc_cred); return err; } +EXPORT_SYMBOL_GPL(rpc_ping); struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) { -- 1.6.4.1