2 * linux/net/sunrpc/clnt.c
4 * This file contains the high-level RPC interface.
5 * It is modeled as a finite state machine to support both synchronous
6 * and asynchronous requests.
8 * - RPC header generation and argument serialization.
9 * - Credential refresh.
10 * - TCP connect handling.
11 * - Retry of operation when it is suspected the operation failed because
12 * of uid squashing on the server, or when the credentials were stale
13 * and need to be refreshed, or when a packet was damaged in transit.
14 * This may be have to be moved to the VFS layer.
16 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
17 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/kallsyms.h>
25 #include <linux/namei.h>
26 #include <linux/mount.h>
27 #include <linux/slab.h>
28 #include <linux/rcupdate.h>
29 #include <linux/utsname.h>
30 #include <linux/workqueue.h>
32 #include <linux/in6.h>
35 #include <linux/sunrpc/clnt.h>
36 #include <linux/sunrpc/addr.h>
37 #include <linux/sunrpc/rpc_pipe_fs.h>
38 #include <linux/sunrpc/metrics.h>
39 #include <linux/sunrpc/bc_xprt.h>
40 #include <trace/events/sunrpc.h>
45 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
46 # define RPCDBG_FACILITY RPCDBG_CALL
49 #define dprint_status(t) \
50 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
51 __func__, t->tk_status)
54 * All RPC clients are linked into this list
57 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
60 static void call_start(struct rpc_task *task);
61 static void call_reserve(struct rpc_task *task);
62 static void call_reserveresult(struct rpc_task *task);
63 static void call_allocate(struct rpc_task *task);
64 static void call_decode(struct rpc_task *task);
65 static void call_bind(struct rpc_task *task);
66 static void call_bind_status(struct rpc_task *task);
67 static void call_transmit(struct rpc_task *task);
68 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
69 static void call_bc_transmit(struct rpc_task *task);
70 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
71 static void call_status(struct rpc_task *task);
72 static void call_transmit_status(struct rpc_task *task);
73 static void call_refresh(struct rpc_task *task);
74 static void call_refreshresult(struct rpc_task *task);
75 static void call_timeout(struct rpc_task *task);
76 static void call_connect(struct rpc_task *task);
77 static void call_connect_status(struct rpc_task *task);
79 static __be32 *rpc_encode_header(struct rpc_task *task);
80 static __be32 *rpc_verify_header(struct rpc_task *task);
81 static int rpc_ping(struct rpc_clnt *clnt);
83 static void rpc_register_client(struct rpc_clnt *clnt)
85 struct net *net = rpc_net_ns(clnt);
86 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
88 spin_lock(&sn->rpc_client_lock);
89 list_add(&clnt->cl_clients, &sn->all_clients);
90 spin_unlock(&sn->rpc_client_lock);
93 static void rpc_unregister_client(struct rpc_clnt *clnt)
95 struct net *net = rpc_net_ns(clnt);
96 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
98 spin_lock(&sn->rpc_client_lock);
99 list_del(&clnt->cl_clients);
100 spin_unlock(&sn->rpc_client_lock);
103 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
105 rpc_remove_client_dir(clnt);
108 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
110 struct net *net = rpc_net_ns(clnt);
111 struct super_block *pipefs_sb;
113 pipefs_sb = rpc_get_sb_net(net);
115 __rpc_clnt_remove_pipedir(clnt);
120 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
121 struct rpc_clnt *clnt)
123 static uint32_t clntid;
124 const char *dir_name = clnt->cl_program->pipe_dir_name;
126 struct dentry *dir, *dentry;
128 dir = rpc_d_lookup_sb(sb, dir_name);
130 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
134 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
135 name[sizeof(name) - 1] = '\0';
136 dentry = rpc_create_client_dir(dir, name, clnt);
139 if (dentry == ERR_PTR(-EEXIST))
141 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
142 " %s/%s, error %ld\n",
143 dir_name, name, PTR_ERR(dentry));
151 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
153 struct dentry *dentry;
155 if (clnt->cl_program->pipe_dir_name != NULL) {
156 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
158 return PTR_ERR(dentry);
163 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
165 if (clnt->cl_program->pipe_dir_name == NULL)
169 case RPC_PIPEFS_MOUNT:
170 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
172 if (atomic_read(&clnt->cl_count) == 0)
175 case RPC_PIPEFS_UMOUNT:
176 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
183 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
184 struct super_block *sb)
186 struct dentry *dentry;
190 case RPC_PIPEFS_MOUNT:
191 dentry = rpc_setup_pipedir_sb(sb, clnt);
195 return PTR_ERR(dentry);
197 case RPC_PIPEFS_UMOUNT:
198 __rpc_clnt_remove_pipedir(clnt);
201 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
207 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
208 struct super_block *sb)
212 for (;; clnt = clnt->cl_parent) {
213 if (!rpc_clnt_skip_event(clnt, event))
214 error = __rpc_clnt_handle_event(clnt, event, sb);
215 if (error || clnt == clnt->cl_parent)
221 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
223 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
224 struct rpc_clnt *clnt;
226 spin_lock(&sn->rpc_client_lock);
227 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
228 if (rpc_clnt_skip_event(clnt, event))
230 spin_unlock(&sn->rpc_client_lock);
233 spin_unlock(&sn->rpc_client_lock);
237 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
240 struct super_block *sb = ptr;
241 struct rpc_clnt *clnt;
244 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
245 error = __rpc_pipefs_event(clnt, event, sb);
252 static struct notifier_block rpc_clients_block = {
253 .notifier_call = rpc_pipefs_event,
254 .priority = SUNRPC_PIPEFS_RPC_PRIO,
257 int rpc_clients_notifier_register(void)
259 return rpc_pipefs_notifier_register(&rpc_clients_block);
262 void rpc_clients_notifier_unregister(void)
264 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
267 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
268 struct rpc_xprt *xprt,
269 const struct rpc_timeout *timeout)
271 struct rpc_xprt *old;
273 spin_lock(&clnt->cl_lock);
274 old = rcu_dereference_protected(clnt->cl_xprt,
275 lockdep_is_held(&clnt->cl_lock));
277 if (!xprt_bound(xprt))
278 clnt->cl_autobind = 1;
280 clnt->cl_timeout = timeout;
281 rcu_assign_pointer(clnt->cl_xprt, xprt);
282 spin_unlock(&clnt->cl_lock);
287 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
289 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
290 nodename, sizeof(clnt->cl_nodename));
293 static int rpc_client_register(struct rpc_clnt *clnt,
294 rpc_authflavor_t pseudoflavor,
295 const char *client_name)
297 struct rpc_auth_create_args auth_args = {
298 .pseudoflavor = pseudoflavor,
299 .target_name = client_name,
301 struct rpc_auth *auth;
302 struct net *net = rpc_net_ns(clnt);
303 struct super_block *pipefs_sb;
306 rpc_clnt_debugfs_register(clnt);
308 pipefs_sb = rpc_get_sb_net(net);
310 err = rpc_setup_pipedir(pipefs_sb, clnt);
315 rpc_register_client(clnt);
319 auth = rpcauth_create(&auth_args, clnt);
321 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
328 pipefs_sb = rpc_get_sb_net(net);
329 rpc_unregister_client(clnt);
330 __rpc_clnt_remove_pipedir(clnt);
334 rpc_clnt_debugfs_unregister(clnt);
338 static DEFINE_IDA(rpc_clids);
340 void rpc_cleanup_clids(void)
342 ida_destroy(&rpc_clids);
345 static int rpc_alloc_clid(struct rpc_clnt *clnt)
349 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
352 clnt->cl_clid = clid;
356 static void rpc_free_clid(struct rpc_clnt *clnt)
358 ida_simple_remove(&rpc_clids, clnt->cl_clid);
361 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
362 struct rpc_xprt *xprt,
363 struct rpc_clnt *parent)
365 const struct rpc_program *program = args->program;
366 const struct rpc_version *version;
367 struct rpc_clnt *clnt = NULL;
368 const struct rpc_timeout *timeout;
369 const char *nodename = args->nodename;
372 /* sanity check the name before trying to print it */
373 dprintk("RPC: creating %s client for %s (xprt %p)\n",
374 program->name, args->servername, xprt);
381 if (args->version >= program->nrvers)
383 version = program->version[args->version];
388 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
391 clnt->cl_parent = parent ? : clnt;
393 err = rpc_alloc_clid(clnt);
397 clnt->cl_procinfo = version->procs;
398 clnt->cl_maxproc = version->nrprocs;
399 clnt->cl_prog = args->prognumber ? : program->number;
400 clnt->cl_vers = version->number;
401 clnt->cl_stats = program->stats;
402 clnt->cl_metrics = rpc_alloc_iostats(clnt);
403 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
405 if (clnt->cl_metrics == NULL)
407 clnt->cl_program = program;
408 INIT_LIST_HEAD(&clnt->cl_tasks);
409 spin_lock_init(&clnt->cl_lock);
411 timeout = xprt->timeout;
412 if (args->timeout != NULL) {
413 memcpy(&clnt->cl_timeout_default, args->timeout,
414 sizeof(clnt->cl_timeout_default));
415 timeout = &clnt->cl_timeout_default;
418 rpc_clnt_set_transport(clnt, xprt, timeout);
420 clnt->cl_rtt = &clnt->cl_rtt_default;
421 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
423 atomic_set(&clnt->cl_count, 1);
425 if (nodename == NULL)
426 nodename = utsname()->nodename;
427 /* save the nodename */
428 rpc_clnt_set_nodename(clnt, nodename);
430 err = rpc_client_register(clnt, args->authflavor, args->client_name);
434 atomic_inc(&parent->cl_count);
438 rpc_free_iostats(clnt->cl_metrics);
450 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
451 struct rpc_xprt *xprt)
453 struct rpc_clnt *clnt = NULL;
455 clnt = rpc_new_client(args, xprt, NULL);
459 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
460 int err = rpc_ping(clnt);
462 rpc_shutdown_client(clnt);
467 clnt->cl_softrtry = 1;
468 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
469 clnt->cl_softrtry = 0;
471 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
472 clnt->cl_autobind = 1;
473 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
474 clnt->cl_noretranstimeo = 1;
475 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
476 clnt->cl_discrtry = 1;
477 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
484 * rpc_create - create an RPC client and transport with one call
485 * @args: rpc_clnt create argument structure
487 * Creates and initializes an RPC transport and an RPC client.
489 * It can ping the server in order to determine if it is up, and to see if
490 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
491 * this behavior so asynchronous tasks can also use rpc_create.
493 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
495 struct rpc_xprt *xprt;
496 struct xprt_create xprtargs = {
498 .ident = args->protocol,
499 .srcaddr = args->saddress,
500 .dstaddr = args->address,
501 .addrlen = args->addrsize,
502 .servername = args->servername,
503 .bc_xprt = args->bc_xprt,
508 WARN_ON(args->protocol != XPRT_TRANSPORT_BC_TCP);
509 xprt = args->bc_xprt->xpt_bc_xprt;
512 return rpc_create_xprt(args, xprt);
516 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
517 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
518 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
519 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
521 * If the caller chooses not to specify a hostname, whip
522 * up a string representation of the passed-in address.
524 if (xprtargs.servername == NULL) {
525 struct sockaddr_un *sun =
526 (struct sockaddr_un *)args->address;
527 struct sockaddr_in *sin =
528 (struct sockaddr_in *)args->address;
529 struct sockaddr_in6 *sin6 =
530 (struct sockaddr_in6 *)args->address;
532 servername[0] = '\0';
533 switch (args->address->sa_family) {
535 snprintf(servername, sizeof(servername), "%s",
539 snprintf(servername, sizeof(servername), "%pI4",
540 &sin->sin_addr.s_addr);
543 snprintf(servername, sizeof(servername), "%pI6",
547 /* caller wants default server name, but
548 * address family isn't recognized. */
549 return ERR_PTR(-EINVAL);
551 xprtargs.servername = servername;
554 xprt = xprt_create_transport(&xprtargs);
556 return (struct rpc_clnt *)xprt;
559 * By default, kernel RPC client connects from a reserved port.
560 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
561 * but it is always enabled for rpciod, which handles the connect
565 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
568 return rpc_create_xprt(args, xprt);
570 EXPORT_SYMBOL_GPL(rpc_create);
573 * This function clones the RPC client structure. It allows us to share the
574 * same transport while varying parameters such as the authentication
577 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
578 struct rpc_clnt *clnt)
580 struct rpc_xprt *xprt;
581 struct rpc_clnt *new;
586 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
590 args->servername = xprt->servername;
591 args->nodename = clnt->cl_nodename;
593 new = rpc_new_client(args, xprt, clnt);
599 /* Turn off autobind on clones */
600 new->cl_autobind = 0;
601 new->cl_softrtry = clnt->cl_softrtry;
602 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
603 new->cl_discrtry = clnt->cl_discrtry;
604 new->cl_chatty = clnt->cl_chatty;
608 dprintk("RPC: %s: returned error %d\n", __func__, err);
613 * rpc_clone_client - Clone an RPC client structure
615 * @clnt: RPC client whose parameters are copied
617 * Returns a fresh RPC client or an ERR_PTR.
619 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
621 struct rpc_create_args args = {
622 .program = clnt->cl_program,
623 .prognumber = clnt->cl_prog,
624 .version = clnt->cl_vers,
625 .authflavor = clnt->cl_auth->au_flavor,
627 return __rpc_clone_client(&args, clnt);
629 EXPORT_SYMBOL_GPL(rpc_clone_client);
632 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
634 * @clnt: RPC client whose parameters are copied
635 * @flavor: security flavor for new client
637 * Returns a fresh RPC client or an ERR_PTR.
640 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
642 struct rpc_create_args args = {
643 .program = clnt->cl_program,
644 .prognumber = clnt->cl_prog,
645 .version = clnt->cl_vers,
646 .authflavor = flavor,
648 return __rpc_clone_client(&args, clnt);
650 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
653 * rpc_switch_client_transport: switch the RPC transport on the fly
654 * @clnt: pointer to a struct rpc_clnt
655 * @args: pointer to the new transport arguments
656 * @timeout: pointer to the new timeout parameters
658 * This function allows the caller to switch the RPC transport for the
659 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
660 * server, for instance. It assumes that the caller has ensured that
661 * there are no active RPC tasks by using some form of locking.
663 * Returns zero if "clnt" is now using the new xprt. Otherwise a
664 * negative errno is returned, and "clnt" continues to use the old
667 int rpc_switch_client_transport(struct rpc_clnt *clnt,
668 struct xprt_create *args,
669 const struct rpc_timeout *timeout)
671 const struct rpc_timeout *old_timeo;
672 rpc_authflavor_t pseudoflavor;
673 struct rpc_xprt *xprt, *old;
674 struct rpc_clnt *parent;
677 xprt = xprt_create_transport(args);
679 dprintk("RPC: failed to create new xprt for clnt %p\n",
681 return PTR_ERR(xprt);
684 pseudoflavor = clnt->cl_auth->au_flavor;
686 old_timeo = clnt->cl_timeout;
687 old = rpc_clnt_set_transport(clnt, xprt, timeout);
689 rpc_unregister_client(clnt);
690 __rpc_clnt_remove_pipedir(clnt);
691 rpc_clnt_debugfs_unregister(clnt);
694 * A new transport was created. "clnt" therefore
695 * becomes the root of a new cl_parent tree. clnt's
696 * children, if it has any, still point to the old xprt.
698 parent = clnt->cl_parent;
699 clnt->cl_parent = clnt;
702 * The old rpc_auth cache cannot be re-used. GSS
703 * contexts in particular are between a single
706 err = rpc_client_register(clnt, pseudoflavor, NULL);
712 rpc_release_client(parent);
714 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
718 rpc_clnt_set_transport(clnt, old, old_timeo);
719 clnt->cl_parent = parent;
720 rpc_client_register(clnt, pseudoflavor, NULL);
722 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
725 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
728 * Kill all tasks for the given client.
729 * XXX: kill their descendants as well?
731 void rpc_killall_tasks(struct rpc_clnt *clnt)
733 struct rpc_task *rovr;
736 if (list_empty(&clnt->cl_tasks))
738 dprintk("RPC: killing all tasks for client %p\n", clnt);
740 * Spin lock all_tasks to prevent changes...
742 spin_lock(&clnt->cl_lock);
743 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
744 if (!RPC_IS_ACTIVATED(rovr))
746 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
747 rovr->tk_flags |= RPC_TASK_KILLED;
748 rpc_exit(rovr, -EIO);
749 if (RPC_IS_QUEUED(rovr))
750 rpc_wake_up_queued_task(rovr->tk_waitqueue,
754 spin_unlock(&clnt->cl_lock);
756 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
759 * Properly shut down an RPC client, terminating all outstanding
762 void rpc_shutdown_client(struct rpc_clnt *clnt)
766 dprintk_rcu("RPC: shutting down %s client for %s\n",
767 clnt->cl_program->name,
768 rcu_dereference(clnt->cl_xprt)->servername);
770 while (!list_empty(&clnt->cl_tasks)) {
771 rpc_killall_tasks(clnt);
772 wait_event_timeout(destroy_wait,
773 list_empty(&clnt->cl_tasks), 1*HZ);
776 rpc_release_client(clnt);
778 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
783 static struct rpc_clnt *
784 rpc_free_client(struct rpc_clnt *clnt)
786 struct rpc_clnt *parent = NULL;
788 dprintk_rcu("RPC: destroying %s client for %s\n",
789 clnt->cl_program->name,
790 rcu_dereference(clnt->cl_xprt)->servername);
791 if (clnt->cl_parent != clnt)
792 parent = clnt->cl_parent;
793 rpc_clnt_debugfs_unregister(clnt);
794 rpc_clnt_remove_pipedir(clnt);
795 rpc_unregister_client(clnt);
796 rpc_free_iostats(clnt->cl_metrics);
797 clnt->cl_metrics = NULL;
798 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
808 static struct rpc_clnt *
809 rpc_free_auth(struct rpc_clnt *clnt)
811 if (clnt->cl_auth == NULL)
812 return rpc_free_client(clnt);
815 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
816 * release remaining GSS contexts. This mechanism ensures
817 * that it can do so safely.
819 atomic_inc(&clnt->cl_count);
820 rpcauth_release(clnt->cl_auth);
821 clnt->cl_auth = NULL;
822 if (atomic_dec_and_test(&clnt->cl_count))
823 return rpc_free_client(clnt);
828 * Release reference to the RPC client
831 rpc_release_client(struct rpc_clnt *clnt)
833 dprintk("RPC: rpc_release_client(%p)\n", clnt);
836 if (list_empty(&clnt->cl_tasks))
837 wake_up(&destroy_wait);
838 if (!atomic_dec_and_test(&clnt->cl_count))
840 clnt = rpc_free_auth(clnt);
841 } while (clnt != NULL);
843 EXPORT_SYMBOL_GPL(rpc_release_client);
846 * rpc_bind_new_program - bind a new RPC program to an existing client
847 * @old: old rpc_client
848 * @program: rpc program to set
849 * @vers: rpc program version
851 * Clones the rpc client and sets up a new RPC program. This is mainly
852 * of use for enabling different RPC programs to share the same transport.
853 * The Sun NFSv2/v3 ACL protocol can do this.
855 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
856 const struct rpc_program *program,
859 struct rpc_create_args args = {
861 .prognumber = program->number,
863 .authflavor = old->cl_auth->au_flavor,
865 struct rpc_clnt *clnt;
868 clnt = __rpc_clone_client(&args, old);
871 err = rpc_ping(clnt);
873 rpc_shutdown_client(clnt);
879 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
881 void rpc_task_release_client(struct rpc_task *task)
883 struct rpc_clnt *clnt = task->tk_client;
886 /* Remove from client task list */
887 spin_lock(&clnt->cl_lock);
888 list_del(&task->tk_task);
889 spin_unlock(&clnt->cl_lock);
890 task->tk_client = NULL;
892 rpc_release_client(clnt);
897 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
900 rpc_task_release_client(task);
901 task->tk_client = clnt;
902 atomic_inc(&clnt->cl_count);
903 if (clnt->cl_softrtry)
904 task->tk_flags |= RPC_TASK_SOFT;
905 if (clnt->cl_noretranstimeo)
906 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
907 if (atomic_read(&clnt->cl_swapper))
908 task->tk_flags |= RPC_TASK_SWAPPER;
909 /* Add to the client's list of all tasks */
910 spin_lock(&clnt->cl_lock);
911 list_add_tail(&task->tk_task, &clnt->cl_tasks);
912 spin_unlock(&clnt->cl_lock);
916 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
918 rpc_task_release_client(task);
919 rpc_task_set_client(task, clnt);
921 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
925 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
928 task->tk_msg.rpc_proc = msg->rpc_proc;
929 task->tk_msg.rpc_argp = msg->rpc_argp;
930 task->tk_msg.rpc_resp = msg->rpc_resp;
931 if (msg->rpc_cred != NULL)
932 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
937 * Default callback for async RPC calls
940 rpc_default_callback(struct rpc_task *task, void *data)
944 static const struct rpc_call_ops rpc_default_ops = {
945 .rpc_call_done = rpc_default_callback,
949 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
950 * @task_setup_data: pointer to task initialisation data
952 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
954 struct rpc_task *task;
956 task = rpc_new_task(task_setup_data);
960 rpc_task_set_client(task, task_setup_data->rpc_client);
961 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
963 if (task->tk_action == NULL)
964 rpc_call_start(task);
966 atomic_inc(&task->tk_count);
971 EXPORT_SYMBOL_GPL(rpc_run_task);
974 * rpc_call_sync - Perform a synchronous RPC call
975 * @clnt: pointer to RPC client
976 * @msg: RPC call parameters
977 * @flags: RPC call flags
979 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
981 struct rpc_task *task;
982 struct rpc_task_setup task_setup_data = {
985 .callback_ops = &rpc_default_ops,
990 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
991 if (flags & RPC_TASK_ASYNC) {
992 rpc_release_calldata(task_setup_data.callback_ops,
993 task_setup_data.callback_data);
997 task = rpc_run_task(&task_setup_data);
999 return PTR_ERR(task);
1000 status = task->tk_status;
1004 EXPORT_SYMBOL_GPL(rpc_call_sync);
1007 * rpc_call_async - Perform an asynchronous RPC call
1008 * @clnt: pointer to RPC client
1009 * @msg: RPC call parameters
1010 * @flags: RPC call flags
1011 * @tk_ops: RPC call ops
1012 * @data: user call data
1015 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1016 const struct rpc_call_ops *tk_ops, void *data)
1018 struct rpc_task *task;
1019 struct rpc_task_setup task_setup_data = {
1022 .callback_ops = tk_ops,
1023 .callback_data = data,
1024 .flags = flags|RPC_TASK_ASYNC,
1027 task = rpc_run_task(&task_setup_data);
1029 return PTR_ERR(task);
1033 EXPORT_SYMBOL_GPL(rpc_call_async);
1035 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1037 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1038 * rpc_execute against it
1041 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1043 struct rpc_task *task;
1044 struct xdr_buf *xbufp = &req->rq_snd_buf;
1045 struct rpc_task_setup task_setup_data = {
1046 .callback_ops = &rpc_default_ops,
1047 .flags = RPC_TASK_SOFTCONN,
1050 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1052 * Create an rpc_task to send the data
1054 task = rpc_new_task(&task_setup_data);
1056 xprt_free_bc_request(req);
1059 task->tk_rqstp = req;
1062 * Set up the xdr_buf length.
1063 * This also indicates that the buffer is XDR encoded already.
1065 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
1066 xbufp->tail[0].iov_len;
1068 task->tk_action = call_bc_transmit;
1069 atomic_inc(&task->tk_count);
1070 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1074 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1077 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1080 rpc_call_start(struct rpc_task *task)
1082 task->tk_action = call_start;
1084 EXPORT_SYMBOL_GPL(rpc_call_start);
1087 * rpc_peeraddr - extract remote peer address from clnt's xprt
1088 * @clnt: RPC client structure
1089 * @buf: target buffer
1090 * @bufsize: length of target buffer
1092 * Returns the number of bytes that are actually in the stored address.
1094 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1097 struct rpc_xprt *xprt;
1100 xprt = rcu_dereference(clnt->cl_xprt);
1102 bytes = xprt->addrlen;
1103 if (bytes > bufsize)
1105 memcpy(buf, &xprt->addr, bytes);
1110 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1113 * rpc_peeraddr2str - return remote peer address in printable format
1114 * @clnt: RPC client structure
1115 * @format: address format
1117 * NB: the lifetime of the memory referenced by the returned pointer is
1118 * the same as the rpc_xprt itself. As long as the caller uses this
1119 * pointer, it must hold the RCU read lock.
1121 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1122 enum rpc_display_format_t format)
1124 struct rpc_xprt *xprt;
1126 xprt = rcu_dereference(clnt->cl_xprt);
1128 if (xprt->address_strings[format] != NULL)
1129 return xprt->address_strings[format];
1131 return "unprintable";
1133 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1135 static const struct sockaddr_in rpc_inaddr_loopback = {
1136 .sin_family = AF_INET,
1137 .sin_addr.s_addr = htonl(INADDR_ANY),
1140 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1141 .sin6_family = AF_INET6,
1142 .sin6_addr = IN6ADDR_ANY_INIT,
1146 * Try a getsockname() on a connected datagram socket. Using a
1147 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1148 * This conserves the ephemeral port number space.
1150 * Returns zero and fills in "buf" if successful; otherwise, a
1151 * negative errno is returned.
1153 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1154 struct sockaddr *buf, int buflen)
1156 struct socket *sock;
1159 err = __sock_create(net, sap->sa_family,
1160 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1162 dprintk("RPC: can't create UDP socket (%d)\n", err);
1166 switch (sap->sa_family) {
1168 err = kernel_bind(sock,
1169 (struct sockaddr *)&rpc_inaddr_loopback,
1170 sizeof(rpc_inaddr_loopback));
1173 err = kernel_bind(sock,
1174 (struct sockaddr *)&rpc_in6addr_loopback,
1175 sizeof(rpc_in6addr_loopback));
1178 err = -EAFNOSUPPORT;
1182 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1186 err = kernel_connect(sock, sap, salen, 0);
1188 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1192 err = kernel_getsockname(sock, buf, &buflen);
1194 dprintk("RPC: getsockname failed (%d)\n", err);
1199 if (buf->sa_family == AF_INET6) {
1200 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1201 sin6->sin6_scope_id = 0;
1203 dprintk("RPC: %s succeeded\n", __func__);
1212 * Scraping a connected socket failed, so we don't have a useable
1213 * local address. Fallback: generate an address that will prevent
1214 * the server from calling us back.
1216 * Returns zero and fills in "buf" if successful; otherwise, a
1217 * negative errno is returned.
1219 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1223 if (buflen < sizeof(rpc_inaddr_loopback))
1225 memcpy(buf, &rpc_inaddr_loopback,
1226 sizeof(rpc_inaddr_loopback));
1229 if (buflen < sizeof(rpc_in6addr_loopback))
1231 memcpy(buf, &rpc_in6addr_loopback,
1232 sizeof(rpc_in6addr_loopback));
1234 dprintk("RPC: %s: address family not supported\n",
1236 return -EAFNOSUPPORT;
1238 dprintk("RPC: %s: succeeded\n", __func__);
1243 * rpc_localaddr - discover local endpoint address for an RPC client
1244 * @clnt: RPC client structure
1245 * @buf: target buffer
1246 * @buflen: size of target buffer, in bytes
1248 * Returns zero and fills in "buf" and "buflen" if successful;
1249 * otherwise, a negative errno is returned.
1251 * This works even if the underlying transport is not currently connected,
1252 * or if the upper layer never previously provided a source address.
1254 * The result of this function call is transient: multiple calls in
1255 * succession may give different results, depending on how local
1256 * networking configuration changes over time.
1258 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1260 struct sockaddr_storage address;
1261 struct sockaddr *sap = (struct sockaddr *)&address;
1262 struct rpc_xprt *xprt;
1268 xprt = rcu_dereference(clnt->cl_xprt);
1269 salen = xprt->addrlen;
1270 memcpy(sap, &xprt->addr, salen);
1271 net = get_net(xprt->xprt_net);
1274 rpc_set_port(sap, 0);
1275 err = rpc_sockname(net, sap, salen, buf, buflen);
1278 /* Couldn't discover local address, return ANYADDR */
1279 return rpc_anyaddr(sap->sa_family, buf, buflen);
1282 EXPORT_SYMBOL_GPL(rpc_localaddr);
1285 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1287 struct rpc_xprt *xprt;
1290 xprt = rcu_dereference(clnt->cl_xprt);
1291 if (xprt->ops->set_buffer_size)
1292 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1295 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1298 * rpc_protocol - Get transport protocol number for an RPC client
1299 * @clnt: RPC client to query
1302 int rpc_protocol(struct rpc_clnt *clnt)
1307 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1311 EXPORT_SYMBOL_GPL(rpc_protocol);
1314 * rpc_net_ns - Get the network namespace for this RPC client
1315 * @clnt: RPC client to query
1318 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1323 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1327 EXPORT_SYMBOL_GPL(rpc_net_ns);
1330 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1331 * @clnt: RPC client to query
1333 * For stream transports, this is one RPC record fragment (see RFC
1334 * 1831), as we don't support multi-record requests yet. For datagram
1335 * transports, this is the size of an IP packet minus the IP, UDP, and
1338 size_t rpc_max_payload(struct rpc_clnt *clnt)
1343 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1347 EXPORT_SYMBOL_GPL(rpc_max_payload);
1350 * rpc_get_timeout - Get timeout for transport in units of HZ
1351 * @clnt: RPC client to query
1353 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1358 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1362 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1365 * rpc_force_rebind - force transport to check that remote port is unchanged
1366 * @clnt: client to rebind
1369 void rpc_force_rebind(struct rpc_clnt *clnt)
1371 if (clnt->cl_autobind) {
1373 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1377 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1380 * Restart an (async) RPC call from the call_prepare state.
1381 * Usually called from within the exit handler.
1384 rpc_restart_call_prepare(struct rpc_task *task)
1386 if (RPC_ASSASSINATED(task))
1388 task->tk_action = call_start;
1389 task->tk_status = 0;
1390 if (task->tk_ops->rpc_call_prepare != NULL)
1391 task->tk_action = rpc_prepare_task;
1394 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1397 * Restart an (async) RPC call. Usually called from within the
1401 rpc_restart_call(struct rpc_task *task)
1403 if (RPC_ASSASSINATED(task))
1405 task->tk_action = call_start;
1406 task->tk_status = 0;
1409 EXPORT_SYMBOL_GPL(rpc_restart_call);
1411 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1413 *rpc_proc_name(const struct rpc_task *task)
1415 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1419 return proc->p_name;
1430 * Other FSM states can be visited zero or more times, but
1431 * this state is visited exactly once for each RPC.
1434 call_start(struct rpc_task *task)
1436 struct rpc_clnt *clnt = task->tk_client;
1438 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1439 clnt->cl_program->name, clnt->cl_vers,
1440 rpc_proc_name(task),
1441 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1443 /* Increment call count */
1444 task->tk_msg.rpc_proc->p_count++;
1445 clnt->cl_stats->rpccnt++;
1446 task->tk_action = call_reserve;
1450 * 1. Reserve an RPC call slot
1453 call_reserve(struct rpc_task *task)
1455 dprint_status(task);
1457 task->tk_status = 0;
1458 task->tk_action = call_reserveresult;
1462 static void call_retry_reserve(struct rpc_task *task);
1465 * 1b. Grok the result of xprt_reserve()
1468 call_reserveresult(struct rpc_task *task)
1470 int status = task->tk_status;
1472 dprint_status(task);
1475 * After a call to xprt_reserve(), we must have either
1476 * a request slot or else an error status.
1478 task->tk_status = 0;
1480 if (task->tk_rqstp) {
1481 task->tk_action = call_refresh;
1485 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1487 rpc_exit(task, -EIO);
1492 * Even though there was an error, we may have acquired
1493 * a request slot somehow. Make sure not to leak it.
1495 if (task->tk_rqstp) {
1496 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1503 rpc_delay(task, HZ >> 2);
1504 case -EAGAIN: /* woken up; retry */
1505 task->tk_action = call_retry_reserve;
1507 case -EIO: /* probably a shutdown */
1510 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1514 rpc_exit(task, status);
1518 * 1c. Retry reserving an RPC call slot
1521 call_retry_reserve(struct rpc_task *task)
1523 dprint_status(task);
1525 task->tk_status = 0;
1526 task->tk_action = call_reserveresult;
1527 xprt_retry_reserve(task);
1531 * 2. Bind and/or refresh the credentials
1534 call_refresh(struct rpc_task *task)
1536 dprint_status(task);
1538 task->tk_action = call_refreshresult;
1539 task->tk_status = 0;
1540 task->tk_client->cl_stats->rpcauthrefresh++;
1541 rpcauth_refreshcred(task);
1545 * 2a. Process the results of a credential refresh
1548 call_refreshresult(struct rpc_task *task)
1550 int status = task->tk_status;
1552 dprint_status(task);
1554 task->tk_status = 0;
1555 task->tk_action = call_refresh;
1558 if (rpcauth_uptodatecred(task)) {
1559 task->tk_action = call_allocate;
1562 /* Use rate-limiting and a max number of retries if refresh
1563 * had status 0 but failed to update the cred.
1566 rpc_delay(task, 3*HZ);
1570 if (!task->tk_cred_retry)
1572 task->tk_cred_retry--;
1573 dprintk("RPC: %5u %s: retry refresh creds\n",
1574 task->tk_pid, __func__);
1577 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1578 task->tk_pid, __func__, status);
1579 rpc_exit(task, status);
1583 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1584 * (Note: buffer memory is freed in xprt_release).
1587 call_allocate(struct rpc_task *task)
1589 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1590 struct rpc_rqst *req = task->tk_rqstp;
1591 struct rpc_xprt *xprt = req->rq_xprt;
1592 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1594 dprint_status(task);
1596 task->tk_status = 0;
1597 task->tk_action = call_bind;
1602 if (proc->p_proc != 0) {
1603 BUG_ON(proc->p_arglen == 0);
1604 if (proc->p_decode != NULL)
1605 BUG_ON(proc->p_replen == 0);
1609 * Calculate the size (in quads) of the RPC call
1610 * and reply headers, and convert both values
1613 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1614 req->rq_callsize <<= 2;
1615 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1616 req->rq_rcvsize <<= 2;
1618 req->rq_buffer = xprt->ops->buf_alloc(task,
1619 req->rq_callsize + req->rq_rcvsize);
1620 if (req->rq_buffer != NULL)
1622 xprt_inject_disconnect(xprt);
1624 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1626 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1627 task->tk_action = call_allocate;
1628 rpc_delay(task, HZ>>4);
1632 rpc_exit(task, -ERESTARTSYS);
1636 rpc_task_need_encode(struct rpc_task *task)
1638 return task->tk_rqstp->rq_snd_buf.len == 0;
1642 rpc_task_force_reencode(struct rpc_task *task)
1644 task->tk_rqstp->rq_snd_buf.len = 0;
1645 task->tk_rqstp->rq_bytes_sent = 0;
1649 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1651 buf->head[0].iov_base = start;
1652 buf->head[0].iov_len = len;
1653 buf->tail[0].iov_len = 0;
1661 * 3. Encode arguments of an RPC call
1664 rpc_xdr_encode(struct rpc_task *task)
1666 struct rpc_rqst *req = task->tk_rqstp;
1670 dprint_status(task);
1672 rpc_xdr_buf_init(&req->rq_snd_buf,
1675 rpc_xdr_buf_init(&req->rq_rcv_buf,
1676 (char *)req->rq_buffer + req->rq_callsize,
1679 p = rpc_encode_header(task);
1681 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1682 rpc_exit(task, -EIO);
1686 encode = task->tk_msg.rpc_proc->p_encode;
1690 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1691 task->tk_msg.rpc_argp);
1695 * 4. Get the server port number if not yet set
1698 call_bind(struct rpc_task *task)
1700 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1702 dprint_status(task);
1704 task->tk_action = call_connect;
1705 if (!xprt_bound(xprt)) {
1706 task->tk_action = call_bind_status;
1707 task->tk_timeout = xprt->bind_timeout;
1708 xprt->ops->rpcbind(task);
1713 * 4a. Sort out bind result
1716 call_bind_status(struct rpc_task *task)
1720 if (task->tk_status >= 0) {
1721 dprint_status(task);
1722 task->tk_status = 0;
1723 task->tk_action = call_connect;
1727 trace_rpc_bind_status(task);
1728 switch (task->tk_status) {
1730 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1731 rpc_delay(task, HZ >> 2);
1734 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1735 "unavailable\n", task->tk_pid);
1736 /* fail immediately if this is an RPC ping */
1737 if (task->tk_msg.rpc_proc->p_proc == 0) {
1738 status = -EOPNOTSUPP;
1741 if (task->tk_rebind_retry == 0)
1743 task->tk_rebind_retry--;
1744 rpc_delay(task, 3*HZ);
1747 dprintk("RPC: %5u rpcbind request timed out\n",
1751 /* server doesn't support any rpcbind version we know of */
1752 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1755 case -EPROTONOSUPPORT:
1756 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1759 case -ECONNREFUSED: /* connection problems */
1768 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1769 task->tk_pid, task->tk_status);
1770 if (!RPC_IS_SOFTCONN(task)) {
1771 rpc_delay(task, 5*HZ);
1774 status = task->tk_status;
1777 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1778 task->tk_pid, -task->tk_status);
1781 rpc_exit(task, status);
1785 task->tk_status = 0;
1786 task->tk_action = call_timeout;
1790 * 4b. Connect to the RPC server
1793 call_connect(struct rpc_task *task)
1795 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1797 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1799 (xprt_connected(xprt) ? "is" : "is not"));
1801 task->tk_action = call_transmit;
1802 if (!xprt_connected(xprt)) {
1803 task->tk_action = call_connect_status;
1804 if (task->tk_status < 0)
1806 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1807 rpc_exit(task, -ENOTCONN);
1815 * 4c. Sort out connect result
1818 call_connect_status(struct rpc_task *task)
1820 struct rpc_clnt *clnt = task->tk_client;
1821 int status = task->tk_status;
1823 dprint_status(task);
1825 trace_rpc_connect_status(task, status);
1826 task->tk_status = 0;
1829 /* A positive refusal suggests a rebind is needed. */
1830 if (RPC_IS_SOFTCONN(task))
1832 if (clnt->cl_autobind) {
1833 rpc_force_rebind(clnt);
1834 task->tk_action = call_bind;
1844 if (RPC_IS_SOFTCONN(task))
1846 /* retry with existing socket, after a delay */
1847 rpc_delay(task, 3*HZ);
1849 /* Check for timeouts before looping back to call_bind */
1851 task->tk_action = call_timeout;
1854 clnt->cl_stats->netreconn++;
1855 task->tk_action = call_transmit;
1858 rpc_exit(task, status);
1862 * 5. Transmit the RPC request, and wait for reply
1865 call_transmit(struct rpc_task *task)
1867 int is_retrans = RPC_WAS_SENT(task);
1869 dprint_status(task);
1871 task->tk_action = call_status;
1872 if (task->tk_status < 0)
1874 if (!xprt_prepare_transmit(task))
1876 task->tk_action = call_transmit_status;
1877 /* Encode here so that rpcsec_gss can use correct sequence number. */
1878 if (rpc_task_need_encode(task)) {
1879 rpc_xdr_encode(task);
1880 /* Did the encode result in an error condition? */
1881 if (task->tk_status != 0) {
1882 /* Was the error nonfatal? */
1883 if (task->tk_status == -EAGAIN)
1884 rpc_delay(task, HZ >> 4);
1886 rpc_exit(task, task->tk_status);
1890 xprt_transmit(task);
1891 if (task->tk_status < 0)
1894 task->tk_client->cl_stats->rpcretrans++;
1896 * On success, ensure that we call xprt_end_transmit() before sleeping
1897 * in order to allow access to the socket to other RPC requests.
1899 call_transmit_status(task);
1900 if (rpc_reply_expected(task))
1902 task->tk_action = rpc_exit_task;
1903 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1907 * 5a. Handle cleanup after a transmission
1910 call_transmit_status(struct rpc_task *task)
1912 task->tk_action = call_status;
1915 * Common case: success. Force the compiler to put this
1918 if (task->tk_status == 0) {
1919 xprt_end_transmit(task);
1920 rpc_task_force_reencode(task);
1924 switch (task->tk_status) {
1929 dprint_status(task);
1930 xprt_end_transmit(task);
1931 rpc_task_force_reencode(task);
1934 * Special cases: if we've been waiting on the
1935 * socket's write_space() callback, or if the
1936 * socket just returned a connection error,
1937 * then hold onto the transport lock.
1944 if (RPC_IS_SOFTCONN(task)) {
1945 xprt_end_transmit(task);
1946 rpc_exit(task, task->tk_status);
1954 rpc_task_force_reencode(task);
1958 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1960 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1961 * addition, disconnect on connectivity errors.
1964 call_bc_transmit(struct rpc_task *task)
1966 struct rpc_rqst *req = task->tk_rqstp;
1968 if (!xprt_prepare_transmit(task))
1971 if (task->tk_status < 0) {
1972 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1973 "error: %d\n", task->tk_status);
1976 if (req->rq_connect_cookie != req->rq_xprt->connect_cookie)
1977 req->rq_bytes_sent = 0;
1979 xprt_transmit(task);
1981 if (task->tk_status == -EAGAIN)
1984 xprt_end_transmit(task);
1985 dprint_status(task);
1986 switch (task->tk_status) {
2000 * Problem reaching the server. Disconnect and let the
2001 * forechannel reestablish the connection. The server will
2002 * have to retransmit the backchannel request and we'll
2003 * reprocess it. Since these ops are idempotent, there's no
2004 * need to cache our reply at this time.
2006 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2007 "error: %d\n", task->tk_status);
2008 xprt_conditional_disconnect(req->rq_xprt,
2009 req->rq_connect_cookie);
2013 * We were unable to reply and will have to drop the
2014 * request. The server should reconnect and retransmit.
2016 WARN_ON_ONCE(task->tk_status == -EAGAIN);
2017 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2018 "error: %d\n", task->tk_status);
2021 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
2023 task->tk_action = rpc_exit_task;
2026 req->rq_connect_cookie = req->rq_xprt->connect_cookie;
2028 task->tk_status = 0;
2030 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
2033 * 6. Sort out the RPC call status
2036 call_status(struct rpc_task *task)
2038 struct rpc_clnt *clnt = task->tk_client;
2039 struct rpc_rqst *req = task->tk_rqstp;
2042 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
2043 task->tk_status = req->rq_reply_bytes_recvd;
2045 dprint_status(task);
2047 status = task->tk_status;
2049 task->tk_action = call_decode;
2053 trace_rpc_call_status(task);
2054 task->tk_status = 0;
2060 if (RPC_IS_SOFTCONN(task)) {
2061 rpc_exit(task, status);
2065 * Delay any retries for 3 seconds, then handle as if it
2068 rpc_delay(task, 3*HZ);
2070 task->tk_action = call_timeout;
2071 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
2072 && task->tk_client->cl_discrtry)
2073 xprt_conditional_disconnect(req->rq_xprt,
2074 req->rq_connect_cookie);
2079 rpc_force_rebind(clnt);
2081 rpc_delay(task, 3*HZ);
2084 task->tk_action = call_bind;
2087 rpc_delay(task, HZ>>2);
2089 task->tk_action = call_transmit;
2092 /* shutdown or soft timeout */
2093 rpc_exit(task, status);
2096 if (clnt->cl_chatty)
2097 printk("%s: RPC call returned error %d\n",
2098 clnt->cl_program->name, -status);
2099 rpc_exit(task, status);
2104 * 6a. Handle RPC timeout
2105 * We do not release the request slot, so we keep using the
2106 * same XID for all retransmits.
2109 call_timeout(struct rpc_task *task)
2111 struct rpc_clnt *clnt = task->tk_client;
2113 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
2114 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
2118 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2119 task->tk_timeouts++;
2121 if (RPC_IS_SOFTCONN(task)) {
2122 rpc_exit(task, -ETIMEDOUT);
2125 if (RPC_IS_SOFT(task)) {
2126 if (clnt->cl_chatty) {
2128 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
2129 clnt->cl_program->name,
2130 rcu_dereference(clnt->cl_xprt)->servername);
2133 if (task->tk_flags & RPC_TASK_TIMEOUT)
2134 rpc_exit(task, -ETIMEDOUT);
2136 rpc_exit(task, -EIO);
2140 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2141 task->tk_flags |= RPC_CALL_MAJORSEEN;
2142 if (clnt->cl_chatty) {
2144 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
2145 clnt->cl_program->name,
2146 rcu_dereference(clnt->cl_xprt)->servername);
2150 rpc_force_rebind(clnt);
2152 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2153 * event? RFC2203 requires the server to drop all such requests.
2155 rpcauth_invalcred(task);
2158 task->tk_action = call_bind;
2159 task->tk_status = 0;
2163 * 7. Decode the RPC reply
2166 call_decode(struct rpc_task *task)
2168 struct rpc_clnt *clnt = task->tk_client;
2169 struct rpc_rqst *req = task->tk_rqstp;
2170 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
2173 dprint_status(task);
2175 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2176 if (clnt->cl_chatty) {
2178 printk(KERN_NOTICE "%s: server %s OK\n",
2179 clnt->cl_program->name,
2180 rcu_dereference(clnt->cl_xprt)->servername);
2183 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2187 * Ensure that we see all writes made by xprt_complete_rqst()
2188 * before it changed req->rq_reply_bytes_recvd.
2191 req->rq_rcv_buf.len = req->rq_private_buf.len;
2193 /* Check that the softirq receive buffer is valid */
2194 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2195 sizeof(req->rq_rcv_buf)) != 0);
2197 if (req->rq_rcv_buf.len < 12) {
2198 if (!RPC_IS_SOFT(task)) {
2199 task->tk_action = call_bind;
2202 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2203 clnt->cl_program->name, task->tk_status);
2204 task->tk_action = call_timeout;
2208 p = rpc_verify_header(task);
2210 if (p == ERR_PTR(-EAGAIN))
2215 task->tk_action = rpc_exit_task;
2218 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2219 task->tk_msg.rpc_resp);
2221 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2225 task->tk_status = 0;
2226 /* Note: rpc_verify_header() may have freed the RPC slot */
2227 if (task->tk_rqstp == req) {
2228 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2229 if (task->tk_client->cl_discrtry)
2230 xprt_conditional_disconnect(req->rq_xprt,
2231 req->rq_connect_cookie);
2236 rpc_encode_header(struct rpc_task *task)
2238 struct rpc_clnt *clnt = task->tk_client;
2239 struct rpc_rqst *req = task->tk_rqstp;
2240 __be32 *p = req->rq_svec[0].iov_base;
2242 /* FIXME: check buffer size? */
2244 p = xprt_skip_transport_header(req->rq_xprt, p);
2245 *p++ = req->rq_xid; /* XID */
2246 *p++ = htonl(RPC_CALL); /* CALL */
2247 *p++ = htonl(RPC_VERSION); /* RPC version */
2248 *p++ = htonl(clnt->cl_prog); /* program number */
2249 *p++ = htonl(clnt->cl_vers); /* program version */
2250 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2251 p = rpcauth_marshcred(task, p);
2252 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2257 rpc_verify_header(struct rpc_task *task)
2259 struct rpc_clnt *clnt = task->tk_client;
2260 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2261 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2262 __be32 *p = iov->iov_base;
2264 int error = -EACCES;
2266 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2267 /* RFC-1014 says that the representation of XDR data must be a
2268 * multiple of four bytes
2269 * - if it isn't pointer subtraction in the NFS client may give
2272 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2273 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2274 task->tk_rqstp->rq_rcv_buf.len);
2281 p += 1; /* skip XID */
2282 if ((n = ntohl(*p++)) != RPC_REPLY) {
2283 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2284 task->tk_pid, __func__, n);
2289 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2292 switch ((n = ntohl(*p++))) {
2293 case RPC_AUTH_ERROR:
2296 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2297 task->tk_pid, __func__);
2298 error = -EPROTONOSUPPORT;
2301 dprintk("RPC: %5u %s: RPC call rejected, "
2302 "unknown error: %x\n",
2303 task->tk_pid, __func__, n);
2309 switch ((n = ntohl(*p++))) {
2310 case RPC_AUTH_REJECTEDCRED:
2311 case RPC_AUTH_REJECTEDVERF:
2312 case RPCSEC_GSS_CREDPROBLEM:
2313 case RPCSEC_GSS_CTXPROBLEM:
2314 if (!task->tk_cred_retry)
2316 task->tk_cred_retry--;
2317 dprintk("RPC: %5u %s: retry stale creds\n",
2318 task->tk_pid, __func__);
2319 rpcauth_invalcred(task);
2320 /* Ensure we obtain a new XID! */
2322 task->tk_action = call_reserve;
2324 case RPC_AUTH_BADCRED:
2325 case RPC_AUTH_BADVERF:
2326 /* possibly garbled cred/verf? */
2327 if (!task->tk_garb_retry)
2329 task->tk_garb_retry--;
2330 dprintk("RPC: %5u %s: retry garbled creds\n",
2331 task->tk_pid, __func__);
2332 task->tk_action = call_bind;
2334 case RPC_AUTH_TOOWEAK:
2336 printk(KERN_NOTICE "RPC: server %s requires stronger "
2337 "authentication.\n",
2338 rcu_dereference(clnt->cl_xprt)->servername);
2342 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2343 task->tk_pid, __func__, n);
2346 dprintk("RPC: %5u %s: call rejected %d\n",
2347 task->tk_pid, __func__, n);
2350 p = rpcauth_checkverf(task, p);
2353 dprintk("RPC: %5u %s: auth check failed with %d\n",
2354 task->tk_pid, __func__, error);
2355 goto out_garbage; /* bad verifier, retry */
2357 len = p - (__be32 *)iov->iov_base - 1;
2360 switch ((n = ntohl(*p++))) {
2363 case RPC_PROG_UNAVAIL:
2364 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2365 "by server %s\n", task->tk_pid, __func__,
2366 (unsigned int)clnt->cl_prog,
2367 rcu_dereference(clnt->cl_xprt)->servername);
2368 error = -EPFNOSUPPORT;
2370 case RPC_PROG_MISMATCH:
2371 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2372 "by server %s\n", task->tk_pid, __func__,
2373 (unsigned int)clnt->cl_prog,
2374 (unsigned int)clnt->cl_vers,
2375 rcu_dereference(clnt->cl_xprt)->servername);
2376 error = -EPROTONOSUPPORT;
2378 case RPC_PROC_UNAVAIL:
2379 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2380 "version %u on server %s\n",
2381 task->tk_pid, __func__,
2382 rpc_proc_name(task),
2383 clnt->cl_prog, clnt->cl_vers,
2384 rcu_dereference(clnt->cl_xprt)->servername);
2385 error = -EOPNOTSUPP;
2387 case RPC_GARBAGE_ARGS:
2388 dprintk("RPC: %5u %s: server saw garbage\n",
2389 task->tk_pid, __func__);
2392 dprintk("RPC: %5u %s: server accept status: %x\n",
2393 task->tk_pid, __func__, n);
2398 clnt->cl_stats->rpcgarbage++;
2399 if (task->tk_garb_retry) {
2400 task->tk_garb_retry--;
2401 dprintk("RPC: %5u %s: retrying\n",
2402 task->tk_pid, __func__);
2403 task->tk_action = call_bind;
2405 return ERR_PTR(-EAGAIN);
2408 rpc_exit(task, error);
2409 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2411 return ERR_PTR(error);
2413 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2418 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2422 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2427 static struct rpc_procinfo rpcproc_null = {
2428 .p_encode = rpcproc_encode_null,
2429 .p_decode = rpcproc_decode_null,
2432 static int rpc_ping(struct rpc_clnt *clnt)
2434 struct rpc_message msg = {
2435 .rpc_proc = &rpcproc_null,
2438 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2439 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2440 put_rpccred(msg.rpc_cred);
2444 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2446 struct rpc_message msg = {
2447 .rpc_proc = &rpcproc_null,
2450 struct rpc_task_setup task_setup_data = {
2452 .rpc_message = &msg,
2453 .callback_ops = &rpc_default_ops,
2456 return rpc_run_task(&task_setup_data);
2458 EXPORT_SYMBOL_GPL(rpc_call_null);
2460 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
2461 static void rpc_show_header(void)
2463 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2464 "-timeout ---ops--\n");
2467 static void rpc_show_task(const struct rpc_clnt *clnt,
2468 const struct rpc_task *task)
2470 const char *rpc_waitq = "none";
2472 if (RPC_IS_QUEUED(task))
2473 rpc_waitq = rpc_qname(task->tk_waitqueue);
2475 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2476 task->tk_pid, task->tk_flags, task->tk_status,
2477 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2478 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2479 task->tk_action, rpc_waitq);
2482 void rpc_show_tasks(struct net *net)
2484 struct rpc_clnt *clnt;
2485 struct rpc_task *task;
2487 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2489 spin_lock(&sn->rpc_client_lock);
2490 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2491 spin_lock(&clnt->cl_lock);
2492 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2497 rpc_show_task(clnt, task);
2499 spin_unlock(&clnt->cl_lock);
2501 spin_unlock(&sn->rpc_client_lock);
2505 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2507 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
2510 struct rpc_xprt *xprt;
2512 if (atomic_inc_return(&clnt->cl_swapper) == 1) {
2515 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
2519 * If we didn't get a reference, then we likely are
2520 * racing with a migration event. Wait for a grace
2521 * period and try again.
2527 ret = xprt_enable_swap(xprt);
2532 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
2535 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
2537 struct rpc_xprt *xprt;
2539 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) {
2542 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
2546 * If we didn't get a reference, then we likely are
2547 * racing with a migration event. Wait for a grace
2548 * period and try again.
2554 xprt_disable_swap(xprt);
2558 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
2559 #endif /* CONFIG_SUNRPC_SWAP */