From: Trond Myklebust Date: Thu, 1 Mar 2012 22:00:56 +0000 (-0500) Subject: SUNRPC: Use RCU to dereference the rpc_clnt.cl_xprt field X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=2446ab6070861aba2dd9229463ffbc40016a9f33;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git SUNRPC: Use RCU to dereference the rpc_clnt.cl_xprt field A migration event will replace the rpc_xprt used by an rpc_clnt. To ensure this can be done safely, all references to cl_xprt must now use a form of rcu_dereference(). Special care is taken with rpc_peeraddr2str(), which returns a pointer to memory whose lifetime is the same as the rpc_xprt. Signed-off-by: Trond Myklebust [ cel: fix lockdep splats and layering violations ] [ cel: forward ported to 3.4 ] [ cel: remove rpc_max_reqs(), add rpc_net_ns() ] Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c index 0e0865e38065..1bb297243624 100644 --- a/fs/nfs/callback_proc.c +++ b/fs/nfs/callback_proc.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "nfs4_fs.h" #include "callback.h" #include "delegation.h" @@ -33,7 +34,7 @@ __be32 nfs4_callback_getattr(struct cb_getattrargs *args, res->bitmap[0] = res->bitmap[1] = 0; res->status = htonl(NFS4ERR_BADHANDLE); - dprintk("NFS: GETATTR callback request from %s\n", + dprintk_rcu("NFS: GETATTR callback request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); inode = nfs_delegation_find_inode(cps->clp, &args->fh); @@ -73,7 +74,7 @@ __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy, if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */ goto out; - dprintk("NFS: RECALL callback request from %s\n", + dprintk_rcu("NFS: RECALL callback request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); res = htonl(NFS4ERR_BADHANDLE); @@ -533,7 +534,7 @@ __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy, if (!cps->clp) /* set in cb_sequence */ goto out; - dprintk("NFS: RECALL_ANY callback request from %s\n", + dprintk_rcu("NFS: RECALL_ANY callback request from %s\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR)); status = cpu_to_be32(NFS4ERR_INVAL); @@ -568,7 +569,7 @@ __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy, if (!cps->clp) /* set in cb_sequence */ goto out; - dprintk("NFS: CB_RECALL_SLOT request from %s target max slots %d\n", + dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target max slots %d\n", rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR), args->crsa_target_max_slots); diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 1506adf4d4ed..d038dc5916e5 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -1284,16 +1284,18 @@ static int nfs4_init_callback(struct nfs_client *clp) int error; if (clp->rpc_ops->version == 4) { + struct rpc_xprt *xprt; + + xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt); + if (nfs4_has_session(clp)) { - error = xprt_setup_backchannel( - clp->cl_rpcclient->cl_xprt, + error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS); if (error < 0) return error; } - error = nfs_callback_up(clp->cl_mvops->minor_version, - clp->cl_rpcclient->cl_xprt); + error = nfs_callback_up(clp->cl_mvops->minor_version, xprt); if (error < 0) { dprintk("%s: failed to start callback. Error = %d\n", __func__, error); @@ -1678,7 +1680,7 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data, data->addrlen, parent_client->cl_ipaddr, data->authflavor, - parent_server->client->cl_xprt->prot, + rpc_protocol(parent_server->client), parent_server->client->cl_timeout, parent_client->cl_mvops->minor_version, parent_client->net); @@ -1905,12 +1907,14 @@ static int nfs_server_list_show(struct seq_file *m, void *v) if (clp->cl_cons_state != NFS_CS_READY) return 0; + rcu_read_lock(); seq_printf(m, "v%u %s %s %3d %s\n", clp->rpc_ops->version, rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR), rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT), atomic_read(&clp->cl_count), clp->cl_hostname); + rcu_read_unlock(); return 0; } @@ -1993,6 +1997,7 @@ static int nfs_volume_list_show(struct seq_file *m, void *v) (unsigned long long) server->fsid.major, (unsigned long long) server->fsid.minor); + rcu_read_lock(); seq_printf(m, "v%u %s %s %-7s %-17s %s\n", clp->rpc_ops->version, rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR), @@ -2000,6 +2005,7 @@ static int nfs_volume_list_show(struct seq_file *m, void *v) dev, fsid, nfs_server_fscache_state(server)); + rcu_read_unlock(); return 0; } diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index 667ea7406fd3..9c8eca315f43 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -96,8 +96,8 @@ static int nfs4_validate_fspath(struct dentry *dentry, static size_t nfs_parse_server_name(char *string, size_t len, struct sockaddr *sa, size_t salen, struct nfs_server *server) { + struct net *net = rpc_net_ns(server->client); ssize_t ret; - struct net *net = server->client->cl_xprt->xprt_net; ret = rpc_pton(net, string, len, sa, salen); if (ret == 0) { diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 6c8e170e2e6b..671510cc14c0 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -3833,6 +3833,7 @@ int nfs4_proc_setclientid(struct nfs_client *clp, u32 program, *p = htonl((u32)clp->cl_boot_time.tv_nsec); for(;;) { + rcu_read_lock(); setclientid.sc_name_len = scnprintf(setclientid.sc_name, sizeof(setclientid.sc_name), "%s/%s %s %s %u", clp->cl_ipaddr, @@ -3849,6 +3850,7 @@ int nfs4_proc_setclientid(struct nfs_client *clp, u32 program, setclientid.sc_uaddr_len = scnprintf(setclientid.sc_uaddr, sizeof(setclientid.sc_uaddr), "%s.%u.%u", clp->cl_ipaddr, port >> 8, port & 255); + rcu_read_unlock(); status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT); if (status != -NFS4ERR_CLID_INUSE) @@ -5244,11 +5246,16 @@ struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp) void nfs4_destroy_session(struct nfs4_session *session) { + struct rpc_xprt *xprt; + nfs4_proc_destroy_session(session); + + rcu_read_lock(); + xprt = rcu_dereference(session->clp->cl_rpcclient->cl_xprt); + rcu_read_unlock(); dprintk("%s Destroy backchannel for xprt %p\n", - __func__, session->clp->cl_rpcclient->cl_xprt); - xprt_destroy_backchannel(session->clp->cl_rpcclient->cl_xprt, - NFS41_BC_MIN_CALLBACKS); + __func__, xprt); + xprt_destroy_backchannel(xprt, NFS41_BC_MIN_CALLBACKS); nfs4_destroy_slot_tables(session); kfree(session); } diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index c1111a37dc14..bae959e294cd 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1037,19 +1037,28 @@ static void nfs4_clear_state_manager_bit(struct nfs_client *clp) void nfs4_schedule_state_manager(struct nfs_client *clp) { struct task_struct *task; + char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1]; if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0) return; __module_get(THIS_MODULE); atomic_inc(&clp->cl_count); - task = kthread_run(nfs4_run_state_manager, clp, "%s-manager", - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR)); - if (!IS_ERR(task)) - return; - nfs4_clear_state_manager_bit(clp); - nfs_put_client(clp); - module_put(THIS_MODULE); + + /* The rcu_read_lock() is not strictly necessary, as the state + * manager is the only thread that ever changes the rpc_xprt + * after it's initialized. At this point, we're single threaded. */ + rcu_read_lock(); + snprintf(buf, sizeof(buf), "%s-manager", + rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR)); + rcu_read_unlock(); + task = kthread_run(nfs4_run_state_manager, clp, buf); + if (IS_ERR(task)) { + printk(KERN_ERR "%s: kthread_run: %ld\n", + __func__, PTR_ERR(task)); + nfs4_clear_state_manager_bit(clp); + nfs_put_client(clp); + module_put(THIS_MODULE); + } } /* diff --git a/fs/nfs/super.c b/fs/nfs/super.c index f4ccdae6a0cf..7002be11d99f 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -53,6 +53,7 @@ #include #include #include +#include #include #include @@ -701,8 +702,10 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, else seq_puts(m, nfs_infop->nostr); } + rcu_read_lock(); seq_printf(m, ",proto=%s", rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); + rcu_read_unlock(); if (version == 4) { if (nfss->port != NFS_PORT) seq_printf(m, ",port=%u", nfss->port); @@ -751,9 +754,11 @@ static int nfs_show_options(struct seq_file *m, struct dentry *root) nfs_show_mount_options(m, nfss, 0); + rcu_read_lock(); seq_printf(m, ",addr=%s", rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient, RPC_DISPLAY_ADDR)); + rcu_read_unlock(); return 0; } diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h index a4c62e95c720..e3d12b4a0314 100644 --- a/include/linux/sunrpc/clnt.h +++ b/include/linux/sunrpc/clnt.h @@ -35,7 +35,7 @@ struct rpc_clnt { struct list_head cl_clients; /* Global list of clients */ struct list_head cl_tasks; /* List of tasks */ spinlock_t cl_lock; /* spinlock */ - struct rpc_xprt * cl_xprt; /* transport */ + struct rpc_xprt __rcu * cl_xprt; /* transport */ struct rpc_procinfo * cl_procinfo; /* procedure info */ u32 cl_prog, /* RPC program number */ cl_vers, /* RPC version number */ @@ -156,6 +156,8 @@ struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int rpc_restart_call_prepare(struct rpc_task *); int rpc_restart_call(struct rpc_task *); void rpc_setbufsize(struct rpc_clnt *, unsigned int, unsigned int); +int rpc_protocol(struct rpc_clnt *); +struct net * rpc_net_ns(struct rpc_clnt *); size_t rpc_max_payload(struct rpc_clnt *); void rpc_force_rebind(struct rpc_clnt *); size_t rpc_peeraddr(struct rpc_clnt *, struct sockaddr *, size_t); diff --git a/include/linux/sunrpc/debug.h b/include/linux/sunrpc/debug.h index b506936f4ce6..6cb2517bcf75 100644 --- a/include/linux/sunrpc/debug.h +++ b/include/linux/sunrpc/debug.h @@ -50,19 +50,32 @@ extern unsigned int nlm_debug; #endif #define dprintk(args...) dfprintk(FACILITY, ## args) +#define dprintk_rcu(args...) dfprintk_rcu(FACILITY, ## args) #undef ifdebug #ifdef RPC_DEBUG # define ifdebug(fac) if (unlikely(rpc_debug & RPCDBG_##fac)) + # define dfprintk(fac, args...) \ do { \ ifdebug(fac) \ printk(KERN_DEFAULT args); \ } while (0) + +# define dfprintk_rcu(fac, args...) \ + do { \ + ifdebug(fac) { \ + rcu_read_lock(); \ + printk(KERN_DEFAULT args); \ + rcu_read_unlock(); \ + } \ + } while (0) + # define RPC_IFDEBUG(x) x #else # define ifdebug(fac) if (0) # define dfprintk(fac, args...) do ; while (0) +# define dfprintk_rcu(fac, args...) do ; while (0) # define RPC_IFDEBUG(x) #endif diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index cb2e56452748..d3ad81f8da5b 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -799,7 +799,7 @@ err_unlink_pipe_1: static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt, struct rpc_auth *auth) { - struct net *net = clnt->cl_xprt->xprt_net; + struct net *net = rpc_net_ns(clnt); struct super_block *sb; sb = rpc_get_sb_net(net); @@ -813,7 +813,7 @@ static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt, static int gss_pipes_dentries_create_net(struct rpc_clnt *clnt, struct rpc_auth *auth) { - struct net *net = clnt->cl_xprt->xprt_net; + struct net *net = rpc_net_ns(clnt); struct super_block *sb; int err = 0; diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 25c3da53fb69..7783fc0e7263 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include @@ -81,7 +82,8 @@ static int rpc_ping(struct rpc_clnt *clnt); static void rpc_register_client(struct rpc_clnt *clnt) { - struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id); + struct net *net = rpc_net_ns(clnt); + struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); list_add(&clnt->cl_clients, &sn->all_clients); @@ -90,7 +92,8 @@ static void rpc_register_client(struct rpc_clnt *clnt) static void rpc_unregister_client(struct rpc_clnt *clnt) { - struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id); + struct net *net = rpc_net_ns(clnt); + struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); list_del(&clnt->cl_clients); @@ -109,12 +112,13 @@ static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) { + struct net *net = rpc_net_ns(clnt); struct super_block *pipefs_sb; - pipefs_sb = rpc_get_sb_net(clnt->cl_xprt->xprt_net); + pipefs_sb = rpc_get_sb_net(net); if (pipefs_sb) { __rpc_clnt_remove_pipedir(clnt); - rpc_put_sb_net(clnt->cl_xprt->xprt_net); + rpc_put_sb_net(net); } } @@ -155,17 +159,18 @@ static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, static int rpc_setup_pipedir(struct rpc_clnt *clnt, const char *dir_name) { + struct net *net = rpc_net_ns(clnt); struct super_block *pipefs_sb; struct dentry *dentry; clnt->cl_dentry = NULL; if (dir_name == NULL) return 0; - pipefs_sb = rpc_get_sb_net(clnt->cl_xprt->xprt_net); + pipefs_sb = rpc_get_sb_net(net); if (!pipefs_sb) return 0; dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt, dir_name); - rpc_put_sb_net(clnt->cl_xprt->xprt_net); + rpc_put_sb_net(net); if (IS_ERR(dentry)) return PTR_ERR(dentry); clnt->cl_dentry = dentry; @@ -295,7 +300,7 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, stru if (clnt->cl_server == NULL) goto out_no_server; - clnt->cl_xprt = xprt; + rcu_assign_pointer(clnt->cl_xprt, xprt); clnt->cl_procinfo = version->procs; clnt->cl_maxproc = version->nrprocs; clnt->cl_protname = program->name; @@ -310,7 +315,7 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, stru INIT_LIST_HEAD(&clnt->cl_tasks); spin_lock_init(&clnt->cl_lock); - if (!xprt_bound(clnt->cl_xprt)) + if (!xprt_bound(xprt)) clnt->cl_autobind = 1; clnt->cl_timeout = xprt->timeout; @@ -477,6 +482,7 @@ struct rpc_clnt * rpc_clone_client(struct rpc_clnt *clnt) { struct rpc_clnt *new; + struct rpc_xprt *xprt; int err = -ENOMEM; new = kmemdup(clnt, sizeof(*new), GFP_KERNEL); @@ -499,18 +505,25 @@ rpc_clone_client(struct rpc_clnt *clnt) if (new->cl_principal == NULL) goto out_no_principal; } + rcu_read_lock(); + xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); + rcu_read_unlock(); + if (xprt == NULL) + goto out_no_transport; + rcu_assign_pointer(new->cl_xprt, xprt); atomic_set(&new->cl_count, 1); err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name); if (err != 0) goto out_no_path; if (new->cl_auth) atomic_inc(&new->cl_auth->au_count); - xprt_get(clnt->cl_xprt); atomic_inc(&clnt->cl_count); rpc_register_client(new); rpciod_up(); return new; out_no_path: + xprt_put(xprt); +out_no_transport: kfree(new->cl_principal); out_no_principal: rpc_free_iostats(new->cl_metrics); @@ -590,7 +603,7 @@ rpc_free_client(struct rpc_clnt *clnt) rpc_free_iostats(clnt->cl_metrics); kfree(clnt->cl_principal); clnt->cl_metrics = NULL; - xprt_put(clnt->cl_xprt); + xprt_put(rcu_dereference_raw(clnt->cl_xprt)); rpciod_down(); kfree(clnt); } @@ -879,13 +892,18 @@ EXPORT_SYMBOL_GPL(rpc_call_start); size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) { size_t bytes; - struct rpc_xprt *xprt = clnt->cl_xprt; + struct rpc_xprt *xprt; + + rcu_read_lock(); + xprt = rcu_dereference(clnt->cl_xprt); - bytes = sizeof(xprt->addr); + bytes = xprt->addrlen; if (bytes > bufsize) bytes = bufsize; - memcpy(buf, &clnt->cl_xprt->addr, bytes); - return xprt->addrlen; + memcpy(buf, &xprt->addr, bytes); + rcu_read_unlock(); + + return bytes; } EXPORT_SYMBOL_GPL(rpc_peeraddr); @@ -894,11 +912,16 @@ EXPORT_SYMBOL_GPL(rpc_peeraddr); * @clnt: RPC client structure * @format: address format * + * NB: the lifetime of the memory referenced by the returned pointer is + * the same as the rpc_xprt itself. As long as the caller uses this + * pointer, it must hold the RCU read lock. */ const char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format) { - struct rpc_xprt *xprt = clnt->cl_xprt; + struct rpc_xprt *xprt; + + xprt = rcu_dereference(clnt->cl_xprt); if (xprt->address_strings[format] != NULL) return xprt->address_strings[format]; @@ -910,14 +933,51 @@ EXPORT_SYMBOL_GPL(rpc_peeraddr2str); void rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) { - struct rpc_xprt *xprt = clnt->cl_xprt; + struct rpc_xprt *xprt; + + rcu_read_lock(); + xprt = rcu_dereference(clnt->cl_xprt); if (xprt->ops->set_buffer_size) xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); + rcu_read_unlock(); } EXPORT_SYMBOL_GPL(rpc_setbufsize); -/* - * Return size of largest payload RPC client can support, in bytes +/** + * rpc_protocol - Get transport protocol number for an RPC client + * @clnt: RPC client to query + * + */ +int rpc_protocol(struct rpc_clnt *clnt) +{ + int protocol; + + rcu_read_lock(); + protocol = rcu_dereference(clnt->cl_xprt)->prot; + rcu_read_unlock(); + return protocol; +} +EXPORT_SYMBOL_GPL(rpc_protocol); + +/** + * rpc_net_ns - Get the network namespace for this RPC client + * @clnt: RPC client to query + * + */ +struct net *rpc_net_ns(struct rpc_clnt *clnt) +{ + struct net *ret; + + rcu_read_lock(); + ret = rcu_dereference(clnt->cl_xprt)->xprt_net; + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(rpc_net_ns); + +/** + * rpc_max_payload - Get maximum payload size for a transport, in bytes + * @clnt: RPC client to query * * For stream transports, this is one RPC record fragment (see RFC * 1831), as we don't support multi-record requests yet. For datagram @@ -926,7 +986,12 @@ EXPORT_SYMBOL_GPL(rpc_setbufsize); */ size_t rpc_max_payload(struct rpc_clnt *clnt) { - return clnt->cl_xprt->max_payload; + size_t ret; + + rcu_read_lock(); + ret = rcu_dereference(clnt->cl_xprt)->max_payload; + rcu_read_unlock(); + return ret; } EXPORT_SYMBOL_GPL(rpc_max_payload); @@ -937,8 +1002,11 @@ EXPORT_SYMBOL_GPL(rpc_max_payload); */ void rpc_force_rebind(struct rpc_clnt *clnt) { - if (clnt->cl_autobind) - xprt_clear_bound(clnt->cl_xprt); + if (clnt->cl_autobind) { + rcu_read_lock(); + xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); + rcu_read_unlock(); + } } EXPORT_SYMBOL_GPL(rpc_force_rebind); diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c index ac9ee1590739..3d30943ed6db 100644 --- a/net/sunrpc/rpc_pipe.c +++ b/net/sunrpc/rpc_pipe.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -402,12 +403,14 @@ rpc_show_info(struct seq_file *m, void *v) { struct rpc_clnt *clnt = m->private; + rcu_read_lock(); seq_printf(m, "RPC server: %s\n", clnt->cl_server); seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_protname, clnt->cl_prog, clnt->cl_vers); seq_printf(m, "address: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); seq_printf(m, "protocol: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PROTO)); seq_printf(m, "port: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PORT)); + rcu_read_unlock(); return 0; } diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c index b1f08bd67883..4f8af63798a2 100644 --- a/net/sunrpc/rpcb_clnt.c +++ b/net/sunrpc/rpcb_clnt.c @@ -620,9 +620,10 @@ static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbi static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt) { struct rpc_clnt *parent = clnt->cl_parent; + struct rpc_xprt *xprt = rcu_dereference(clnt->cl_xprt); while (parent != clnt) { - if (parent->cl_xprt != clnt->cl_xprt) + if (rcu_dereference(parent->cl_xprt) != xprt) break; if (clnt->cl_autobind) break; @@ -653,8 +654,12 @@ void rpcb_getport_async(struct rpc_task *task) size_t salen; int status; - clnt = rpcb_find_transport_owner(task->tk_client); - xprt = clnt->cl_xprt; + rcu_read_lock(); + do { + clnt = rpcb_find_transport_owner(task->tk_client); + xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); + } while (xprt == NULL); + rcu_read_unlock(); dprintk("RPC: %5u %s(%s, %u, %u, %d)\n", task->tk_pid, __func__, @@ -667,6 +672,7 @@ void rpcb_getport_async(struct rpc_task *task) if (xprt_test_and_set_binding(xprt)) { dprintk("RPC: %5u %s: waiting for another binder\n", task->tk_pid, __func__); + xprt_put(xprt); return; } @@ -734,7 +740,7 @@ void rpcb_getport_async(struct rpc_task *task) switch (bind_version) { case RPCBVERS_4: case RPCBVERS_3: - map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID); + map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID]; map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC); map->r_owner = ""; break; @@ -763,6 +769,7 @@ bailout_release_client: bailout_nofree: rpcb_wake_rpcbind_waiters(xprt, status); task->tk_status = status; + xprt_put(xprt); } EXPORT_SYMBOL_GPL(rpcb_getport_async); diff --git a/net/sunrpc/stats.c b/net/sunrpc/stats.c index 1eb3304bc105..bc2068ee795b 100644 --- a/net/sunrpc/stats.c +++ b/net/sunrpc/stats.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "netns.h" @@ -179,7 +180,7 @@ static void _print_name(struct seq_file *seq, unsigned int op, void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt) { struct rpc_iostats *stats = clnt->cl_metrics; - struct rpc_xprt *xprt = clnt->cl_xprt; + struct rpc_xprt *xprt; unsigned int op, maxproc = clnt->cl_maxproc; if (!stats) @@ -189,8 +190,11 @@ void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt) seq_printf(seq, "p/v: %u/%u (%s)\n", clnt->cl_prog, clnt->cl_vers, clnt->cl_protname); + rcu_read_lock(); + xprt = rcu_dereference(clnt->cl_xprt); if (xprt) xprt->ops->print_stats(xprt, seq); + rcu_read_unlock(); seq_printf(seq, "\tper-op statistics\n"); for (op = 0; op < maxproc; op++) {