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 static int rpc_alloc_clid(struct rpc_clnt *clnt)
344 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
347 clnt->cl_clid = clid;
351 static void rpc_free_clid(struct rpc_clnt *clnt)
353 ida_simple_remove(&rpc_clids, clnt->cl_clid);
356 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
357 struct rpc_xprt *xprt,
358 struct rpc_clnt *parent)
360 const struct rpc_program *program = args->program;
361 const struct rpc_version *version;
362 struct rpc_clnt *clnt = NULL;
363 const struct rpc_timeout *timeout;
364 const char *nodename = args->nodename;
367 /* sanity check the name before trying to print it */
368 dprintk("RPC: creating %s client for %s (xprt %p)\n",
369 program->name, args->servername, xprt);
376 if (args->version >= program->nrvers)
378 version = program->version[args->version];
383 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
386 clnt->cl_parent = parent ? : clnt;
388 err = rpc_alloc_clid(clnt);
392 clnt->cl_procinfo = version->procs;
393 clnt->cl_maxproc = version->nrprocs;
394 clnt->cl_prog = args->prognumber ? : program->number;
395 clnt->cl_vers = version->number;
396 clnt->cl_stats = program->stats;
397 clnt->cl_metrics = rpc_alloc_iostats(clnt);
398 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
400 if (clnt->cl_metrics == NULL)
402 clnt->cl_program = program;
403 INIT_LIST_HEAD(&clnt->cl_tasks);
404 spin_lock_init(&clnt->cl_lock);
406 timeout = xprt->timeout;
407 if (args->timeout != NULL) {
408 memcpy(&clnt->cl_timeout_default, args->timeout,
409 sizeof(clnt->cl_timeout_default));
410 timeout = &clnt->cl_timeout_default;
413 rpc_clnt_set_transport(clnt, xprt, timeout);
415 clnt->cl_rtt = &clnt->cl_rtt_default;
416 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
418 atomic_set(&clnt->cl_count, 1);
420 if (nodename == NULL)
421 nodename = utsname()->nodename;
422 /* save the nodename */
423 rpc_clnt_set_nodename(clnt, nodename);
425 err = rpc_client_register(clnt, args->authflavor, args->client_name);
429 atomic_inc(&parent->cl_count);
433 rpc_free_iostats(clnt->cl_metrics);
445 struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
446 struct rpc_xprt *xprt)
448 struct rpc_clnt *clnt = NULL;
450 clnt = rpc_new_client(args, xprt, NULL);
454 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
455 int err = rpc_ping(clnt);
457 rpc_shutdown_client(clnt);
462 clnt->cl_softrtry = 1;
463 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
464 clnt->cl_softrtry = 0;
466 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
467 clnt->cl_autobind = 1;
468 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
469 clnt->cl_noretranstimeo = 1;
470 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
471 clnt->cl_discrtry = 1;
472 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
477 EXPORT_SYMBOL_GPL(rpc_create_xprt);
480 * rpc_create - create an RPC client and transport with one call
481 * @args: rpc_clnt create argument structure
483 * Creates and initializes an RPC transport and an RPC client.
485 * It can ping the server in order to determine if it is up, and to see if
486 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
487 * this behavior so asynchronous tasks can also use rpc_create.
489 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
491 struct rpc_xprt *xprt;
492 struct xprt_create xprtargs = {
494 .ident = args->protocol,
495 .srcaddr = args->saddress,
496 .dstaddr = args->address,
497 .addrlen = args->addrsize,
498 .servername = args->servername,
499 .bc_xprt = args->bc_xprt,
503 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
504 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
505 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
506 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
508 * If the caller chooses not to specify a hostname, whip
509 * up a string representation of the passed-in address.
511 if (xprtargs.servername == NULL) {
512 struct sockaddr_un *sun =
513 (struct sockaddr_un *)args->address;
514 struct sockaddr_in *sin =
515 (struct sockaddr_in *)args->address;
516 struct sockaddr_in6 *sin6 =
517 (struct sockaddr_in6 *)args->address;
519 servername[0] = '\0';
520 switch (args->address->sa_family) {
522 snprintf(servername, sizeof(servername), "%s",
526 snprintf(servername, sizeof(servername), "%pI4",
527 &sin->sin_addr.s_addr);
530 snprintf(servername, sizeof(servername), "%pI6",
534 /* caller wants default server name, but
535 * address family isn't recognized. */
536 return ERR_PTR(-EINVAL);
538 xprtargs.servername = servername;
541 xprt = xprt_create_transport(&xprtargs);
543 return (struct rpc_clnt *)xprt;
546 * By default, kernel RPC client connects from a reserved port.
547 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
548 * but it is always enabled for rpciod, which handles the connect
552 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
555 return rpc_create_xprt(args, xprt);
557 EXPORT_SYMBOL_GPL(rpc_create);
560 * This function clones the RPC client structure. It allows us to share the
561 * same transport while varying parameters such as the authentication
564 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
565 struct rpc_clnt *clnt)
567 struct rpc_xprt *xprt;
568 struct rpc_clnt *new;
573 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
577 args->servername = xprt->servername;
578 args->nodename = clnt->cl_nodename;
580 new = rpc_new_client(args, xprt, clnt);
586 /* Turn off autobind on clones */
587 new->cl_autobind = 0;
588 new->cl_softrtry = clnt->cl_softrtry;
589 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
590 new->cl_discrtry = clnt->cl_discrtry;
591 new->cl_chatty = clnt->cl_chatty;
595 dprintk("RPC: %s: returned error %d\n", __func__, err);
600 * rpc_clone_client - Clone an RPC client structure
602 * @clnt: RPC client whose parameters are copied
604 * Returns a fresh RPC client or an ERR_PTR.
606 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
608 struct rpc_create_args args = {
609 .program = clnt->cl_program,
610 .prognumber = clnt->cl_prog,
611 .version = clnt->cl_vers,
612 .authflavor = clnt->cl_auth->au_flavor,
614 return __rpc_clone_client(&args, clnt);
616 EXPORT_SYMBOL_GPL(rpc_clone_client);
619 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
621 * @clnt: RPC client whose parameters are copied
622 * @flavor: security flavor for new client
624 * Returns a fresh RPC client or an ERR_PTR.
627 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
629 struct rpc_create_args args = {
630 .program = clnt->cl_program,
631 .prognumber = clnt->cl_prog,
632 .version = clnt->cl_vers,
633 .authflavor = flavor,
635 return __rpc_clone_client(&args, clnt);
637 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
640 * rpc_switch_client_transport: switch the RPC transport on the fly
641 * @clnt: pointer to a struct rpc_clnt
642 * @args: pointer to the new transport arguments
643 * @timeout: pointer to the new timeout parameters
645 * This function allows the caller to switch the RPC transport for the
646 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
647 * server, for instance. It assumes that the caller has ensured that
648 * there are no active RPC tasks by using some form of locking.
650 * Returns zero if "clnt" is now using the new xprt. Otherwise a
651 * negative errno is returned, and "clnt" continues to use the old
654 int rpc_switch_client_transport(struct rpc_clnt *clnt,
655 struct xprt_create *args,
656 const struct rpc_timeout *timeout)
658 const struct rpc_timeout *old_timeo;
659 rpc_authflavor_t pseudoflavor;
660 struct rpc_xprt *xprt, *old;
661 struct rpc_clnt *parent;
664 xprt = xprt_create_transport(args);
666 dprintk("RPC: failed to create new xprt for clnt %p\n",
668 return PTR_ERR(xprt);
671 pseudoflavor = clnt->cl_auth->au_flavor;
673 old_timeo = clnt->cl_timeout;
674 old = rpc_clnt_set_transport(clnt, xprt, timeout);
676 rpc_unregister_client(clnt);
677 __rpc_clnt_remove_pipedir(clnt);
678 rpc_clnt_debugfs_unregister(clnt);
681 * A new transport was created. "clnt" therefore
682 * becomes the root of a new cl_parent tree. clnt's
683 * children, if it has any, still point to the old xprt.
685 parent = clnt->cl_parent;
686 clnt->cl_parent = clnt;
689 * The old rpc_auth cache cannot be re-used. GSS
690 * contexts in particular are between a single
693 err = rpc_client_register(clnt, pseudoflavor, NULL);
699 rpc_release_client(parent);
701 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
705 rpc_clnt_set_transport(clnt, old, old_timeo);
706 clnt->cl_parent = parent;
707 rpc_client_register(clnt, pseudoflavor, NULL);
709 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
712 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
715 * Kill all tasks for the given client.
716 * XXX: kill their descendants as well?
718 void rpc_killall_tasks(struct rpc_clnt *clnt)
720 struct rpc_task *rovr;
723 if (list_empty(&clnt->cl_tasks))
725 dprintk("RPC: killing all tasks for client %p\n", clnt);
727 * Spin lock all_tasks to prevent changes...
729 spin_lock(&clnt->cl_lock);
730 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
731 if (!RPC_IS_ACTIVATED(rovr))
733 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
734 rovr->tk_flags |= RPC_TASK_KILLED;
735 rpc_exit(rovr, -EIO);
736 if (RPC_IS_QUEUED(rovr))
737 rpc_wake_up_queued_task(rovr->tk_waitqueue,
741 spin_unlock(&clnt->cl_lock);
743 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
746 * Properly shut down an RPC client, terminating all outstanding
749 void rpc_shutdown_client(struct rpc_clnt *clnt)
753 dprintk_rcu("RPC: shutting down %s client for %s\n",
754 clnt->cl_program->name,
755 rcu_dereference(clnt->cl_xprt)->servername);
757 while (!list_empty(&clnt->cl_tasks)) {
758 rpc_killall_tasks(clnt);
759 wait_event_timeout(destroy_wait,
760 list_empty(&clnt->cl_tasks), 1*HZ);
763 rpc_release_client(clnt);
765 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
770 static struct rpc_clnt *
771 rpc_free_client(struct rpc_clnt *clnt)
773 struct rpc_clnt *parent = NULL;
775 dprintk_rcu("RPC: destroying %s client for %s\n",
776 clnt->cl_program->name,
777 rcu_dereference(clnt->cl_xprt)->servername);
778 if (clnt->cl_parent != clnt)
779 parent = clnt->cl_parent;
780 rpc_clnt_debugfs_unregister(clnt);
781 rpc_clnt_remove_pipedir(clnt);
782 rpc_unregister_client(clnt);
783 rpc_free_iostats(clnt->cl_metrics);
784 clnt->cl_metrics = NULL;
785 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
795 static struct rpc_clnt *
796 rpc_free_auth(struct rpc_clnt *clnt)
798 if (clnt->cl_auth == NULL)
799 return rpc_free_client(clnt);
802 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
803 * release remaining GSS contexts. This mechanism ensures
804 * that it can do so safely.
806 atomic_inc(&clnt->cl_count);
807 rpcauth_release(clnt->cl_auth);
808 clnt->cl_auth = NULL;
809 if (atomic_dec_and_test(&clnt->cl_count))
810 return rpc_free_client(clnt);
815 * Release reference to the RPC client
818 rpc_release_client(struct rpc_clnt *clnt)
820 dprintk("RPC: rpc_release_client(%p)\n", clnt);
823 if (list_empty(&clnt->cl_tasks))
824 wake_up(&destroy_wait);
825 if (!atomic_dec_and_test(&clnt->cl_count))
827 clnt = rpc_free_auth(clnt);
828 } while (clnt != NULL);
830 EXPORT_SYMBOL_GPL(rpc_release_client);
833 * rpc_bind_new_program - bind a new RPC program to an existing client
834 * @old: old rpc_client
835 * @program: rpc program to set
836 * @vers: rpc program version
838 * Clones the rpc client and sets up a new RPC program. This is mainly
839 * of use for enabling different RPC programs to share the same transport.
840 * The Sun NFSv2/v3 ACL protocol can do this.
842 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
843 const struct rpc_program *program,
846 struct rpc_create_args args = {
848 .prognumber = program->number,
850 .authflavor = old->cl_auth->au_flavor,
852 struct rpc_clnt *clnt;
855 clnt = __rpc_clone_client(&args, old);
858 err = rpc_ping(clnt);
860 rpc_shutdown_client(clnt);
866 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
868 void rpc_task_release_client(struct rpc_task *task)
870 struct rpc_clnt *clnt = task->tk_client;
873 /* Remove from client task list */
874 spin_lock(&clnt->cl_lock);
875 list_del(&task->tk_task);
876 spin_unlock(&clnt->cl_lock);
877 task->tk_client = NULL;
879 rpc_release_client(clnt);
884 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
887 rpc_task_release_client(task);
888 task->tk_client = clnt;
889 atomic_inc(&clnt->cl_count);
890 if (clnt->cl_softrtry)
891 task->tk_flags |= RPC_TASK_SOFT;
892 if (clnt->cl_noretranstimeo)
893 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
894 if (atomic_read(&clnt->cl_swapper))
895 task->tk_flags |= RPC_TASK_SWAPPER;
896 /* Add to the client's list of all tasks */
897 spin_lock(&clnt->cl_lock);
898 list_add_tail(&task->tk_task, &clnt->cl_tasks);
899 spin_unlock(&clnt->cl_lock);
903 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
905 rpc_task_release_client(task);
906 rpc_task_set_client(task, clnt);
908 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
912 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
915 task->tk_msg.rpc_proc = msg->rpc_proc;
916 task->tk_msg.rpc_argp = msg->rpc_argp;
917 task->tk_msg.rpc_resp = msg->rpc_resp;
918 if (msg->rpc_cred != NULL)
919 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
924 * Default callback for async RPC calls
927 rpc_default_callback(struct rpc_task *task, void *data)
931 static const struct rpc_call_ops rpc_default_ops = {
932 .rpc_call_done = rpc_default_callback,
936 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
937 * @task_setup_data: pointer to task initialisation data
939 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
941 struct rpc_task *task;
943 task = rpc_new_task(task_setup_data);
947 rpc_task_set_client(task, task_setup_data->rpc_client);
948 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
950 if (task->tk_action == NULL)
951 rpc_call_start(task);
953 atomic_inc(&task->tk_count);
958 EXPORT_SYMBOL_GPL(rpc_run_task);
961 * rpc_call_sync - Perform a synchronous RPC call
962 * @clnt: pointer to RPC client
963 * @msg: RPC call parameters
964 * @flags: RPC call flags
966 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
968 struct rpc_task *task;
969 struct rpc_task_setup task_setup_data = {
972 .callback_ops = &rpc_default_ops,
977 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
978 if (flags & RPC_TASK_ASYNC) {
979 rpc_release_calldata(task_setup_data.callback_ops,
980 task_setup_data.callback_data);
984 task = rpc_run_task(&task_setup_data);
986 return PTR_ERR(task);
987 status = task->tk_status;
991 EXPORT_SYMBOL_GPL(rpc_call_sync);
994 * rpc_call_async - Perform an asynchronous RPC call
995 * @clnt: pointer to RPC client
996 * @msg: RPC call parameters
997 * @flags: RPC call flags
998 * @tk_ops: RPC call ops
999 * @data: user call data
1002 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1003 const struct rpc_call_ops *tk_ops, void *data)
1005 struct rpc_task *task;
1006 struct rpc_task_setup task_setup_data = {
1009 .callback_ops = tk_ops,
1010 .callback_data = data,
1011 .flags = flags|RPC_TASK_ASYNC,
1014 task = rpc_run_task(&task_setup_data);
1016 return PTR_ERR(task);
1020 EXPORT_SYMBOL_GPL(rpc_call_async);
1022 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1024 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1025 * rpc_execute against it
1028 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1030 struct rpc_task *task;
1031 struct xdr_buf *xbufp = &req->rq_snd_buf;
1032 struct rpc_task_setup task_setup_data = {
1033 .callback_ops = &rpc_default_ops,
1036 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1038 * Create an rpc_task to send the data
1040 task = rpc_new_task(&task_setup_data);
1042 xprt_free_bc_request(req);
1045 task->tk_rqstp = req;
1048 * Set up the xdr_buf length.
1049 * This also indicates that the buffer is XDR encoded already.
1051 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
1052 xbufp->tail[0].iov_len;
1054 task->tk_action = call_bc_transmit;
1055 atomic_inc(&task->tk_count);
1056 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1060 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1063 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1066 rpc_call_start(struct rpc_task *task)
1068 task->tk_action = call_start;
1070 EXPORT_SYMBOL_GPL(rpc_call_start);
1073 * rpc_peeraddr - extract remote peer address from clnt's xprt
1074 * @clnt: RPC client structure
1075 * @buf: target buffer
1076 * @bufsize: length of target buffer
1078 * Returns the number of bytes that are actually in the stored address.
1080 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1083 struct rpc_xprt *xprt;
1086 xprt = rcu_dereference(clnt->cl_xprt);
1088 bytes = xprt->addrlen;
1089 if (bytes > bufsize)
1091 memcpy(buf, &xprt->addr, bytes);
1096 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1099 * rpc_peeraddr2str - return remote peer address in printable format
1100 * @clnt: RPC client structure
1101 * @format: address format
1103 * NB: the lifetime of the memory referenced by the returned pointer is
1104 * the same as the rpc_xprt itself. As long as the caller uses this
1105 * pointer, it must hold the RCU read lock.
1107 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1108 enum rpc_display_format_t format)
1110 struct rpc_xprt *xprt;
1112 xprt = rcu_dereference(clnt->cl_xprt);
1114 if (xprt->address_strings[format] != NULL)
1115 return xprt->address_strings[format];
1117 return "unprintable";
1119 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1121 static const struct sockaddr_in rpc_inaddr_loopback = {
1122 .sin_family = AF_INET,
1123 .sin_addr.s_addr = htonl(INADDR_ANY),
1126 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1127 .sin6_family = AF_INET6,
1128 .sin6_addr = IN6ADDR_ANY_INIT,
1132 * Try a getsockname() on a connected datagram socket. Using a
1133 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1134 * This conserves the ephemeral port number space.
1136 * Returns zero and fills in "buf" if successful; otherwise, a
1137 * negative errno is returned.
1139 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1140 struct sockaddr *buf, int buflen)
1142 struct socket *sock;
1145 err = __sock_create(net, sap->sa_family,
1146 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1148 dprintk("RPC: can't create UDP socket (%d)\n", err);
1152 switch (sap->sa_family) {
1154 err = kernel_bind(sock,
1155 (struct sockaddr *)&rpc_inaddr_loopback,
1156 sizeof(rpc_inaddr_loopback));
1159 err = kernel_bind(sock,
1160 (struct sockaddr *)&rpc_in6addr_loopback,
1161 sizeof(rpc_in6addr_loopback));
1164 err = -EAFNOSUPPORT;
1168 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1172 err = kernel_connect(sock, sap, salen, 0);
1174 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1178 err = kernel_getsockname(sock, buf, &buflen);
1180 dprintk("RPC: getsockname failed (%d)\n", err);
1185 if (buf->sa_family == AF_INET6) {
1186 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1187 sin6->sin6_scope_id = 0;
1189 dprintk("RPC: %s succeeded\n", __func__);
1198 * Scraping a connected socket failed, so we don't have a useable
1199 * local address. Fallback: generate an address that will prevent
1200 * the server from calling us back.
1202 * Returns zero and fills in "buf" if successful; otherwise, a
1203 * negative errno is returned.
1205 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1209 if (buflen < sizeof(rpc_inaddr_loopback))
1211 memcpy(buf, &rpc_inaddr_loopback,
1212 sizeof(rpc_inaddr_loopback));
1215 if (buflen < sizeof(rpc_in6addr_loopback))
1217 memcpy(buf, &rpc_in6addr_loopback,
1218 sizeof(rpc_in6addr_loopback));
1220 dprintk("RPC: %s: address family not supported\n",
1222 return -EAFNOSUPPORT;
1224 dprintk("RPC: %s: succeeded\n", __func__);
1229 * rpc_localaddr - discover local endpoint address for an RPC client
1230 * @clnt: RPC client structure
1231 * @buf: target buffer
1232 * @buflen: size of target buffer, in bytes
1234 * Returns zero and fills in "buf" and "buflen" if successful;
1235 * otherwise, a negative errno is returned.
1237 * This works even if the underlying transport is not currently connected,
1238 * or if the upper layer never previously provided a source address.
1240 * The result of this function call is transient: multiple calls in
1241 * succession may give different results, depending on how local
1242 * networking configuration changes over time.
1244 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1246 struct sockaddr_storage address;
1247 struct sockaddr *sap = (struct sockaddr *)&address;
1248 struct rpc_xprt *xprt;
1254 xprt = rcu_dereference(clnt->cl_xprt);
1255 salen = xprt->addrlen;
1256 memcpy(sap, &xprt->addr, salen);
1257 net = get_net(xprt->xprt_net);
1260 rpc_set_port(sap, 0);
1261 err = rpc_sockname(net, sap, salen, buf, buflen);
1264 /* Couldn't discover local address, return ANYADDR */
1265 return rpc_anyaddr(sap->sa_family, buf, buflen);
1268 EXPORT_SYMBOL_GPL(rpc_localaddr);
1271 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1273 struct rpc_xprt *xprt;
1276 xprt = rcu_dereference(clnt->cl_xprt);
1277 if (xprt->ops->set_buffer_size)
1278 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1281 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1284 * rpc_protocol - Get transport protocol number for an RPC client
1285 * @clnt: RPC client to query
1288 int rpc_protocol(struct rpc_clnt *clnt)
1293 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1297 EXPORT_SYMBOL_GPL(rpc_protocol);
1300 * rpc_net_ns - Get the network namespace for this RPC client
1301 * @clnt: RPC client to query
1304 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1309 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1313 EXPORT_SYMBOL_GPL(rpc_net_ns);
1316 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1317 * @clnt: RPC client to query
1319 * For stream transports, this is one RPC record fragment (see RFC
1320 * 1831), as we don't support multi-record requests yet. For datagram
1321 * transports, this is the size of an IP packet minus the IP, UDP, and
1324 size_t rpc_max_payload(struct rpc_clnt *clnt)
1329 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1333 EXPORT_SYMBOL_GPL(rpc_max_payload);
1336 * rpc_get_timeout - Get timeout for transport in units of HZ
1337 * @clnt: RPC client to query
1339 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1344 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1348 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1351 * rpc_force_rebind - force transport to check that remote port is unchanged
1352 * @clnt: client to rebind
1355 void rpc_force_rebind(struct rpc_clnt *clnt)
1357 if (clnt->cl_autobind) {
1359 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1363 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1366 * Restart an (async) RPC call from the call_prepare state.
1367 * Usually called from within the exit handler.
1370 rpc_restart_call_prepare(struct rpc_task *task)
1372 if (RPC_ASSASSINATED(task))
1374 task->tk_action = call_start;
1375 task->tk_status = 0;
1376 if (task->tk_ops->rpc_call_prepare != NULL)
1377 task->tk_action = rpc_prepare_task;
1380 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1383 * Restart an (async) RPC call. Usually called from within the
1387 rpc_restart_call(struct rpc_task *task)
1389 if (RPC_ASSASSINATED(task))
1391 task->tk_action = call_start;
1392 task->tk_status = 0;
1395 EXPORT_SYMBOL_GPL(rpc_restart_call);
1397 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1399 *rpc_proc_name(const struct rpc_task *task)
1401 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1405 return proc->p_name;
1416 * Other FSM states can be visited zero or more times, but
1417 * this state is visited exactly once for each RPC.
1420 call_start(struct rpc_task *task)
1422 struct rpc_clnt *clnt = task->tk_client;
1424 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1425 clnt->cl_program->name, clnt->cl_vers,
1426 rpc_proc_name(task),
1427 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1429 /* Increment call count */
1430 task->tk_msg.rpc_proc->p_count++;
1431 clnt->cl_stats->rpccnt++;
1432 task->tk_action = call_reserve;
1436 * 1. Reserve an RPC call slot
1439 call_reserve(struct rpc_task *task)
1441 dprint_status(task);
1443 task->tk_status = 0;
1444 task->tk_action = call_reserveresult;
1448 static void call_retry_reserve(struct rpc_task *task);
1451 * 1b. Grok the result of xprt_reserve()
1454 call_reserveresult(struct rpc_task *task)
1456 int status = task->tk_status;
1458 dprint_status(task);
1461 * After a call to xprt_reserve(), we must have either
1462 * a request slot or else an error status.
1464 task->tk_status = 0;
1466 if (task->tk_rqstp) {
1467 task->tk_action = call_refresh;
1471 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1473 rpc_exit(task, -EIO);
1478 * Even though there was an error, we may have acquired
1479 * a request slot somehow. Make sure not to leak it.
1481 if (task->tk_rqstp) {
1482 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1489 rpc_delay(task, HZ >> 2);
1490 case -EAGAIN: /* woken up; retry */
1491 task->tk_action = call_retry_reserve;
1493 case -EIO: /* probably a shutdown */
1496 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1500 rpc_exit(task, status);
1504 * 1c. Retry reserving an RPC call slot
1507 call_retry_reserve(struct rpc_task *task)
1509 dprint_status(task);
1511 task->tk_status = 0;
1512 task->tk_action = call_reserveresult;
1513 xprt_retry_reserve(task);
1517 * 2. Bind and/or refresh the credentials
1520 call_refresh(struct rpc_task *task)
1522 dprint_status(task);
1524 task->tk_action = call_refreshresult;
1525 task->tk_status = 0;
1526 task->tk_client->cl_stats->rpcauthrefresh++;
1527 rpcauth_refreshcred(task);
1531 * 2a. Process the results of a credential refresh
1534 call_refreshresult(struct rpc_task *task)
1536 int status = task->tk_status;
1538 dprint_status(task);
1540 task->tk_status = 0;
1541 task->tk_action = call_refresh;
1544 if (rpcauth_uptodatecred(task)) {
1545 task->tk_action = call_allocate;
1548 /* Use rate-limiting and a max number of retries if refresh
1549 * had status 0 but failed to update the cred.
1552 rpc_delay(task, 3*HZ);
1556 if (!task->tk_cred_retry)
1558 task->tk_cred_retry--;
1559 dprintk("RPC: %5u %s: retry refresh creds\n",
1560 task->tk_pid, __func__);
1563 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1564 task->tk_pid, __func__, status);
1565 rpc_exit(task, status);
1569 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1570 * (Note: buffer memory is freed in xprt_release).
1573 call_allocate(struct rpc_task *task)
1575 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1576 struct rpc_rqst *req = task->tk_rqstp;
1577 struct rpc_xprt *xprt = req->rq_xprt;
1578 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1580 dprint_status(task);
1582 task->tk_status = 0;
1583 task->tk_action = call_bind;
1588 if (proc->p_proc != 0) {
1589 BUG_ON(proc->p_arglen == 0);
1590 if (proc->p_decode != NULL)
1591 BUG_ON(proc->p_replen == 0);
1595 * Calculate the size (in quads) of the RPC call
1596 * and reply headers, and convert both values
1599 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1600 req->rq_callsize <<= 2;
1601 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1602 req->rq_rcvsize <<= 2;
1604 req->rq_buffer = xprt->ops->buf_alloc(task,
1605 req->rq_callsize + req->rq_rcvsize);
1606 if (req->rq_buffer != NULL)
1608 xprt_inject_disconnect(xprt);
1610 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1612 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1613 task->tk_action = call_allocate;
1614 rpc_delay(task, HZ>>4);
1618 rpc_exit(task, -ERESTARTSYS);
1622 rpc_task_need_encode(struct rpc_task *task)
1624 return task->tk_rqstp->rq_snd_buf.len == 0;
1628 rpc_task_force_reencode(struct rpc_task *task)
1630 task->tk_rqstp->rq_snd_buf.len = 0;
1631 task->tk_rqstp->rq_bytes_sent = 0;
1635 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1637 buf->head[0].iov_base = start;
1638 buf->head[0].iov_len = len;
1639 buf->tail[0].iov_len = 0;
1647 * 3. Encode arguments of an RPC call
1650 rpc_xdr_encode(struct rpc_task *task)
1652 struct rpc_rqst *req = task->tk_rqstp;
1656 dprint_status(task);
1658 rpc_xdr_buf_init(&req->rq_snd_buf,
1661 rpc_xdr_buf_init(&req->rq_rcv_buf,
1662 (char *)req->rq_buffer + req->rq_callsize,
1665 p = rpc_encode_header(task);
1667 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1668 rpc_exit(task, -EIO);
1672 encode = task->tk_msg.rpc_proc->p_encode;
1676 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1677 task->tk_msg.rpc_argp);
1681 * 4. Get the server port number if not yet set
1684 call_bind(struct rpc_task *task)
1686 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1688 dprint_status(task);
1690 task->tk_action = call_connect;
1691 if (!xprt_bound(xprt)) {
1692 task->tk_action = call_bind_status;
1693 task->tk_timeout = xprt->bind_timeout;
1694 xprt->ops->rpcbind(task);
1699 * 4a. Sort out bind result
1702 call_bind_status(struct rpc_task *task)
1706 if (task->tk_status >= 0) {
1707 dprint_status(task);
1708 task->tk_status = 0;
1709 task->tk_action = call_connect;
1713 trace_rpc_bind_status(task);
1714 switch (task->tk_status) {
1716 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1717 rpc_delay(task, HZ >> 2);
1720 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1721 "unavailable\n", task->tk_pid);
1722 /* fail immediately if this is an RPC ping */
1723 if (task->tk_msg.rpc_proc->p_proc == 0) {
1724 status = -EOPNOTSUPP;
1727 if (task->tk_rebind_retry == 0)
1729 task->tk_rebind_retry--;
1730 rpc_delay(task, 3*HZ);
1733 dprintk("RPC: %5u rpcbind request timed out\n",
1737 /* server doesn't support any rpcbind version we know of */
1738 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1741 case -EPROTONOSUPPORT:
1742 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1745 case -ECONNREFUSED: /* connection problems */
1754 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1755 task->tk_pid, task->tk_status);
1756 if (!RPC_IS_SOFTCONN(task)) {
1757 rpc_delay(task, 5*HZ);
1760 status = task->tk_status;
1763 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1764 task->tk_pid, -task->tk_status);
1767 rpc_exit(task, status);
1771 task->tk_status = 0;
1772 task->tk_action = call_timeout;
1776 * 4b. Connect to the RPC server
1779 call_connect(struct rpc_task *task)
1781 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1783 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1785 (xprt_connected(xprt) ? "is" : "is not"));
1787 task->tk_action = call_transmit;
1788 if (!xprt_connected(xprt)) {
1789 task->tk_action = call_connect_status;
1790 if (task->tk_status < 0)
1792 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1793 rpc_exit(task, -ENOTCONN);
1801 * 4c. Sort out connect result
1804 call_connect_status(struct rpc_task *task)
1806 struct rpc_clnt *clnt = task->tk_client;
1807 int status = task->tk_status;
1809 dprint_status(task);
1811 trace_rpc_connect_status(task, status);
1812 task->tk_status = 0;
1822 if (RPC_IS_SOFTCONN(task))
1824 /* retry with existing socket, after a delay */
1825 rpc_delay(task, 3*HZ);
1827 /* Check for timeouts before looping back to call_bind */
1829 task->tk_action = call_timeout;
1832 clnt->cl_stats->netreconn++;
1833 task->tk_action = call_transmit;
1836 rpc_exit(task, status);
1840 * 5. Transmit the RPC request, and wait for reply
1843 call_transmit(struct rpc_task *task)
1845 int is_retrans = RPC_WAS_SENT(task);
1847 dprint_status(task);
1849 task->tk_action = call_status;
1850 if (task->tk_status < 0)
1852 if (!xprt_prepare_transmit(task))
1854 task->tk_action = call_transmit_status;
1855 /* Encode here so that rpcsec_gss can use correct sequence number. */
1856 if (rpc_task_need_encode(task)) {
1857 rpc_xdr_encode(task);
1858 /* Did the encode result in an error condition? */
1859 if (task->tk_status != 0) {
1860 /* Was the error nonfatal? */
1861 if (task->tk_status == -EAGAIN)
1862 rpc_delay(task, HZ >> 4);
1864 rpc_exit(task, task->tk_status);
1868 xprt_transmit(task);
1869 if (task->tk_status < 0)
1872 task->tk_client->cl_stats->rpcretrans++;
1874 * On success, ensure that we call xprt_end_transmit() before sleeping
1875 * in order to allow access to the socket to other RPC requests.
1877 call_transmit_status(task);
1878 if (rpc_reply_expected(task))
1880 task->tk_action = rpc_exit_task;
1881 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1885 * 5a. Handle cleanup after a transmission
1888 call_transmit_status(struct rpc_task *task)
1890 task->tk_action = call_status;
1893 * Common case: success. Force the compiler to put this
1896 if (task->tk_status == 0) {
1897 xprt_end_transmit(task);
1898 rpc_task_force_reencode(task);
1902 switch (task->tk_status) {
1906 dprint_status(task);
1907 xprt_end_transmit(task);
1908 rpc_task_force_reencode(task);
1911 * Special cases: if we've been waiting on the
1912 * socket's write_space() callback, or if the
1913 * socket just returned a connection error,
1914 * then hold onto the transport lock.
1921 if (RPC_IS_SOFTCONN(task)) {
1922 xprt_end_transmit(task);
1923 rpc_exit(task, task->tk_status);
1932 rpc_task_force_reencode(task);
1936 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1938 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1939 * addition, disconnect on connectivity errors.
1942 call_bc_transmit(struct rpc_task *task)
1944 struct rpc_rqst *req = task->tk_rqstp;
1946 if (!xprt_prepare_transmit(task))
1949 if (task->tk_status < 0) {
1950 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1951 "error: %d\n", task->tk_status);
1954 if (req->rq_connect_cookie != req->rq_xprt->connect_cookie)
1955 req->rq_bytes_sent = 0;
1957 xprt_transmit(task);
1959 if (task->tk_status == -EAGAIN)
1962 xprt_end_transmit(task);
1963 dprint_status(task);
1964 switch (task->tk_status) {
1973 * Problem reaching the server. Disconnect and let the
1974 * forechannel reestablish the connection. The server will
1975 * have to retransmit the backchannel request and we'll
1976 * reprocess it. Since these ops are idempotent, there's no
1977 * need to cache our reply at this time.
1979 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1980 "error: %d\n", task->tk_status);
1981 xprt_conditional_disconnect(req->rq_xprt,
1982 req->rq_connect_cookie);
1986 * We were unable to reply and will have to drop the
1987 * request. The server should reconnect and retransmit.
1989 WARN_ON_ONCE(task->tk_status == -EAGAIN);
1990 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1991 "error: %d\n", task->tk_status);
1994 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1996 task->tk_action = rpc_exit_task;
1999 req->rq_connect_cookie = req->rq_xprt->connect_cookie;
2001 task->tk_status = 0;
2003 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
2006 * 6. Sort out the RPC call status
2009 call_status(struct rpc_task *task)
2011 struct rpc_clnt *clnt = task->tk_client;
2012 struct rpc_rqst *req = task->tk_rqstp;
2015 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
2016 task->tk_status = req->rq_reply_bytes_recvd;
2018 dprint_status(task);
2020 status = task->tk_status;
2022 task->tk_action = call_decode;
2026 trace_rpc_call_status(task);
2027 task->tk_status = 0;
2033 if (RPC_IS_SOFTCONN(task)) {
2034 rpc_exit(task, status);
2038 * Delay any retries for 3 seconds, then handle as if it
2041 rpc_delay(task, 3*HZ);
2043 task->tk_action = call_timeout;
2044 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
2045 && task->tk_client->cl_discrtry)
2046 xprt_conditional_disconnect(req->rq_xprt,
2047 req->rq_connect_cookie);
2052 rpc_force_rebind(clnt);
2055 rpc_delay(task, 3*HZ);
2058 task->tk_action = call_bind;
2061 task->tk_action = call_transmit;
2064 /* shutdown or soft timeout */
2065 rpc_exit(task, status);
2068 if (clnt->cl_chatty)
2069 printk("%s: RPC call returned error %d\n",
2070 clnt->cl_program->name, -status);
2071 rpc_exit(task, status);
2076 * 6a. Handle RPC timeout
2077 * We do not release the request slot, so we keep using the
2078 * same XID for all retransmits.
2081 call_timeout(struct rpc_task *task)
2083 struct rpc_clnt *clnt = task->tk_client;
2085 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
2086 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
2090 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2091 task->tk_timeouts++;
2093 if (RPC_IS_SOFTCONN(task)) {
2094 rpc_exit(task, -ETIMEDOUT);
2097 if (RPC_IS_SOFT(task)) {
2098 if (clnt->cl_chatty) {
2100 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
2101 clnt->cl_program->name,
2102 rcu_dereference(clnt->cl_xprt)->servername);
2105 if (task->tk_flags & RPC_TASK_TIMEOUT)
2106 rpc_exit(task, -ETIMEDOUT);
2108 rpc_exit(task, -EIO);
2112 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2113 task->tk_flags |= RPC_CALL_MAJORSEEN;
2114 if (clnt->cl_chatty) {
2116 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
2117 clnt->cl_program->name,
2118 rcu_dereference(clnt->cl_xprt)->servername);
2122 rpc_force_rebind(clnt);
2124 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2125 * event? RFC2203 requires the server to drop all such requests.
2127 rpcauth_invalcred(task);
2130 task->tk_action = call_bind;
2131 task->tk_status = 0;
2135 * 7. Decode the RPC reply
2138 call_decode(struct rpc_task *task)
2140 struct rpc_clnt *clnt = task->tk_client;
2141 struct rpc_rqst *req = task->tk_rqstp;
2142 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
2145 dprint_status(task);
2147 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2148 if (clnt->cl_chatty) {
2150 printk(KERN_NOTICE "%s: server %s OK\n",
2151 clnt->cl_program->name,
2152 rcu_dereference(clnt->cl_xprt)->servername);
2155 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2159 * Ensure that we see all writes made by xprt_complete_rqst()
2160 * before it changed req->rq_reply_bytes_recvd.
2163 req->rq_rcv_buf.len = req->rq_private_buf.len;
2165 /* Check that the softirq receive buffer is valid */
2166 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2167 sizeof(req->rq_rcv_buf)) != 0);
2169 if (req->rq_rcv_buf.len < 12) {
2170 if (!RPC_IS_SOFT(task)) {
2171 task->tk_action = call_bind;
2174 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2175 clnt->cl_program->name, task->tk_status);
2176 task->tk_action = call_timeout;
2180 p = rpc_verify_header(task);
2182 if (p == ERR_PTR(-EAGAIN))
2187 task->tk_action = rpc_exit_task;
2190 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2191 task->tk_msg.rpc_resp);
2193 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2197 task->tk_status = 0;
2198 /* Note: rpc_verify_header() may have freed the RPC slot */
2199 if (task->tk_rqstp == req) {
2200 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2201 if (task->tk_client->cl_discrtry)
2202 xprt_conditional_disconnect(req->rq_xprt,
2203 req->rq_connect_cookie);
2208 rpc_encode_header(struct rpc_task *task)
2210 struct rpc_clnt *clnt = task->tk_client;
2211 struct rpc_rqst *req = task->tk_rqstp;
2212 __be32 *p = req->rq_svec[0].iov_base;
2214 /* FIXME: check buffer size? */
2216 p = xprt_skip_transport_header(req->rq_xprt, p);
2217 *p++ = req->rq_xid; /* XID */
2218 *p++ = htonl(RPC_CALL); /* CALL */
2219 *p++ = htonl(RPC_VERSION); /* RPC version */
2220 *p++ = htonl(clnt->cl_prog); /* program number */
2221 *p++ = htonl(clnt->cl_vers); /* program version */
2222 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2223 p = rpcauth_marshcred(task, p);
2224 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2229 rpc_verify_header(struct rpc_task *task)
2231 struct rpc_clnt *clnt = task->tk_client;
2232 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2233 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2234 __be32 *p = iov->iov_base;
2236 int error = -EACCES;
2238 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2239 /* RFC-1014 says that the representation of XDR data must be a
2240 * multiple of four bytes
2241 * - if it isn't pointer subtraction in the NFS client may give
2244 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2245 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2246 task->tk_rqstp->rq_rcv_buf.len);
2253 p += 1; /* skip XID */
2254 if ((n = ntohl(*p++)) != RPC_REPLY) {
2255 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2256 task->tk_pid, __func__, n);
2261 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2264 switch ((n = ntohl(*p++))) {
2265 case RPC_AUTH_ERROR:
2268 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2269 task->tk_pid, __func__);
2270 error = -EPROTONOSUPPORT;
2273 dprintk("RPC: %5u %s: RPC call rejected, "
2274 "unknown error: %x\n",
2275 task->tk_pid, __func__, n);
2281 switch ((n = ntohl(*p++))) {
2282 case RPC_AUTH_REJECTEDCRED:
2283 case RPC_AUTH_REJECTEDVERF:
2284 case RPCSEC_GSS_CREDPROBLEM:
2285 case RPCSEC_GSS_CTXPROBLEM:
2286 if (!task->tk_cred_retry)
2288 task->tk_cred_retry--;
2289 dprintk("RPC: %5u %s: retry stale creds\n",
2290 task->tk_pid, __func__);
2291 rpcauth_invalcred(task);
2292 /* Ensure we obtain a new XID! */
2294 task->tk_action = call_reserve;
2296 case RPC_AUTH_BADCRED:
2297 case RPC_AUTH_BADVERF:
2298 /* possibly garbled cred/verf? */
2299 if (!task->tk_garb_retry)
2301 task->tk_garb_retry--;
2302 dprintk("RPC: %5u %s: retry garbled creds\n",
2303 task->tk_pid, __func__);
2304 task->tk_action = call_bind;
2306 case RPC_AUTH_TOOWEAK:
2308 printk(KERN_NOTICE "RPC: server %s requires stronger "
2309 "authentication.\n",
2310 rcu_dereference(clnt->cl_xprt)->servername);
2314 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2315 task->tk_pid, __func__, n);
2318 dprintk("RPC: %5u %s: call rejected %d\n",
2319 task->tk_pid, __func__, n);
2322 p = rpcauth_checkverf(task, p);
2325 dprintk("RPC: %5u %s: auth check failed with %d\n",
2326 task->tk_pid, __func__, error);
2327 goto out_garbage; /* bad verifier, retry */
2329 len = p - (__be32 *)iov->iov_base - 1;
2332 switch ((n = ntohl(*p++))) {
2335 case RPC_PROG_UNAVAIL:
2336 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2337 "by server %s\n", task->tk_pid, __func__,
2338 (unsigned int)clnt->cl_prog,
2339 rcu_dereference(clnt->cl_xprt)->servername);
2340 error = -EPFNOSUPPORT;
2342 case RPC_PROG_MISMATCH:
2343 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2344 "by server %s\n", task->tk_pid, __func__,
2345 (unsigned int)clnt->cl_prog,
2346 (unsigned int)clnt->cl_vers,
2347 rcu_dereference(clnt->cl_xprt)->servername);
2348 error = -EPROTONOSUPPORT;
2350 case RPC_PROC_UNAVAIL:
2351 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2352 "version %u on server %s\n",
2353 task->tk_pid, __func__,
2354 rpc_proc_name(task),
2355 clnt->cl_prog, clnt->cl_vers,
2356 rcu_dereference(clnt->cl_xprt)->servername);
2357 error = -EOPNOTSUPP;
2359 case RPC_GARBAGE_ARGS:
2360 dprintk("RPC: %5u %s: server saw garbage\n",
2361 task->tk_pid, __func__);
2364 dprintk("RPC: %5u %s: server accept status: %x\n",
2365 task->tk_pid, __func__, n);
2370 clnt->cl_stats->rpcgarbage++;
2371 if (task->tk_garb_retry) {
2372 task->tk_garb_retry--;
2373 dprintk("RPC: %5u %s: retrying\n",
2374 task->tk_pid, __func__);
2375 task->tk_action = call_bind;
2377 return ERR_PTR(-EAGAIN);
2380 rpc_exit(task, error);
2381 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2383 return ERR_PTR(error);
2385 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2390 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2394 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2399 static struct rpc_procinfo rpcproc_null = {
2400 .p_encode = rpcproc_encode_null,
2401 .p_decode = rpcproc_decode_null,
2404 static int rpc_ping(struct rpc_clnt *clnt)
2406 struct rpc_message msg = {
2407 .rpc_proc = &rpcproc_null,
2410 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2411 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2412 put_rpccred(msg.rpc_cred);
2416 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2418 struct rpc_message msg = {
2419 .rpc_proc = &rpcproc_null,
2422 struct rpc_task_setup task_setup_data = {
2424 .rpc_message = &msg,
2425 .callback_ops = &rpc_default_ops,
2428 return rpc_run_task(&task_setup_data);
2430 EXPORT_SYMBOL_GPL(rpc_call_null);
2432 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
2433 static void rpc_show_header(void)
2435 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2436 "-timeout ---ops--\n");
2439 static void rpc_show_task(const struct rpc_clnt *clnt,
2440 const struct rpc_task *task)
2442 const char *rpc_waitq = "none";
2444 if (RPC_IS_QUEUED(task))
2445 rpc_waitq = rpc_qname(task->tk_waitqueue);
2447 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2448 task->tk_pid, task->tk_flags, task->tk_status,
2449 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2450 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2451 task->tk_action, rpc_waitq);
2454 void rpc_show_tasks(struct net *net)
2456 struct rpc_clnt *clnt;
2457 struct rpc_task *task;
2459 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2461 spin_lock(&sn->rpc_client_lock);
2462 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2463 spin_lock(&clnt->cl_lock);
2464 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2469 rpc_show_task(clnt, task);
2471 spin_unlock(&clnt->cl_lock);
2473 spin_unlock(&sn->rpc_client_lock);
2477 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2479 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
2482 struct rpc_xprt *xprt;
2484 if (atomic_inc_return(&clnt->cl_swapper) == 1) {
2487 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
2491 * If we didn't get a reference, then we likely are
2492 * racing with a migration event. Wait for a grace
2493 * period and try again.
2499 ret = xprt_enable_swap(xprt);
2504 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
2507 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
2509 struct rpc_xprt *xprt;
2511 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) {
2514 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
2518 * If we didn't get a reference, then we likely are
2519 * racing with a migration event. Wait for a grace
2520 * period and try again.
2526 xprt_disable_swap(xprt);
2530 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
2531 #endif /* CONFIG_SUNRPC_SWAP */