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 static 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))
479 * rpc_create - create an RPC client and transport with one call
480 * @args: rpc_clnt create argument structure
482 * Creates and initializes an RPC transport and an RPC client.
484 * It can ping the server in order to determine if it is up, and to see if
485 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
486 * this behavior so asynchronous tasks can also use rpc_create.
488 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
490 struct rpc_xprt *xprt;
491 struct xprt_create xprtargs = {
493 .ident = args->protocol,
494 .srcaddr = args->saddress,
495 .dstaddr = args->address,
496 .addrlen = args->addrsize,
497 .servername = args->servername,
498 .bc_xprt = args->bc_xprt,
503 WARN_ON(args->protocol != XPRT_TRANSPORT_BC_TCP);
504 xprt = args->bc_xprt->xpt_bc_xprt;
507 return rpc_create_xprt(args, xprt);
511 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
512 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
513 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
514 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
516 * If the caller chooses not to specify a hostname, whip
517 * up a string representation of the passed-in address.
519 if (xprtargs.servername == NULL) {
520 struct sockaddr_un *sun =
521 (struct sockaddr_un *)args->address;
522 struct sockaddr_in *sin =
523 (struct sockaddr_in *)args->address;
524 struct sockaddr_in6 *sin6 =
525 (struct sockaddr_in6 *)args->address;
527 servername[0] = '\0';
528 switch (args->address->sa_family) {
530 snprintf(servername, sizeof(servername), "%s",
534 snprintf(servername, sizeof(servername), "%pI4",
535 &sin->sin_addr.s_addr);
538 snprintf(servername, sizeof(servername), "%pI6",
542 /* caller wants default server name, but
543 * address family isn't recognized. */
544 return ERR_PTR(-EINVAL);
546 xprtargs.servername = servername;
549 xprt = xprt_create_transport(&xprtargs);
551 return (struct rpc_clnt *)xprt;
554 * By default, kernel RPC client connects from a reserved port.
555 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
556 * but it is always enabled for rpciod, which handles the connect
560 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
563 return rpc_create_xprt(args, xprt);
565 EXPORT_SYMBOL_GPL(rpc_create);
568 * This function clones the RPC client structure. It allows us to share the
569 * same transport while varying parameters such as the authentication
572 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
573 struct rpc_clnt *clnt)
575 struct rpc_xprt *xprt;
576 struct rpc_clnt *new;
581 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
585 args->servername = xprt->servername;
586 args->nodename = clnt->cl_nodename;
588 new = rpc_new_client(args, xprt, clnt);
594 /* Turn off autobind on clones */
595 new->cl_autobind = 0;
596 new->cl_softrtry = clnt->cl_softrtry;
597 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
598 new->cl_discrtry = clnt->cl_discrtry;
599 new->cl_chatty = clnt->cl_chatty;
603 dprintk("RPC: %s: returned error %d\n", __func__, err);
608 * rpc_clone_client - Clone an RPC client structure
610 * @clnt: RPC client whose parameters are copied
612 * Returns a fresh RPC client or an ERR_PTR.
614 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
616 struct rpc_create_args args = {
617 .program = clnt->cl_program,
618 .prognumber = clnt->cl_prog,
619 .version = clnt->cl_vers,
620 .authflavor = clnt->cl_auth->au_flavor,
622 return __rpc_clone_client(&args, clnt);
624 EXPORT_SYMBOL_GPL(rpc_clone_client);
627 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
629 * @clnt: RPC client whose parameters are copied
630 * @flavor: security flavor for new client
632 * Returns a fresh RPC client or an ERR_PTR.
635 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
637 struct rpc_create_args args = {
638 .program = clnt->cl_program,
639 .prognumber = clnt->cl_prog,
640 .version = clnt->cl_vers,
641 .authflavor = flavor,
643 return __rpc_clone_client(&args, clnt);
645 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
648 * rpc_switch_client_transport: switch the RPC transport on the fly
649 * @clnt: pointer to a struct rpc_clnt
650 * @args: pointer to the new transport arguments
651 * @timeout: pointer to the new timeout parameters
653 * This function allows the caller to switch the RPC transport for the
654 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
655 * server, for instance. It assumes that the caller has ensured that
656 * there are no active RPC tasks by using some form of locking.
658 * Returns zero if "clnt" is now using the new xprt. Otherwise a
659 * negative errno is returned, and "clnt" continues to use the old
662 int rpc_switch_client_transport(struct rpc_clnt *clnt,
663 struct xprt_create *args,
664 const struct rpc_timeout *timeout)
666 const struct rpc_timeout *old_timeo;
667 rpc_authflavor_t pseudoflavor;
668 struct rpc_xprt *xprt, *old;
669 struct rpc_clnt *parent;
672 xprt = xprt_create_transport(args);
674 dprintk("RPC: failed to create new xprt for clnt %p\n",
676 return PTR_ERR(xprt);
679 pseudoflavor = clnt->cl_auth->au_flavor;
681 old_timeo = clnt->cl_timeout;
682 old = rpc_clnt_set_transport(clnt, xprt, timeout);
684 rpc_unregister_client(clnt);
685 __rpc_clnt_remove_pipedir(clnt);
686 rpc_clnt_debugfs_unregister(clnt);
689 * A new transport was created. "clnt" therefore
690 * becomes the root of a new cl_parent tree. clnt's
691 * children, if it has any, still point to the old xprt.
693 parent = clnt->cl_parent;
694 clnt->cl_parent = clnt;
697 * The old rpc_auth cache cannot be re-used. GSS
698 * contexts in particular are between a single
701 err = rpc_client_register(clnt, pseudoflavor, NULL);
707 rpc_release_client(parent);
709 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
713 rpc_clnt_set_transport(clnt, old, old_timeo);
714 clnt->cl_parent = parent;
715 rpc_client_register(clnt, pseudoflavor, NULL);
717 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
720 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
723 * Kill all tasks for the given client.
724 * XXX: kill their descendants as well?
726 void rpc_killall_tasks(struct rpc_clnt *clnt)
728 struct rpc_task *rovr;
731 if (list_empty(&clnt->cl_tasks))
733 dprintk("RPC: killing all tasks for client %p\n", clnt);
735 * Spin lock all_tasks to prevent changes...
737 spin_lock(&clnt->cl_lock);
738 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
739 if (!RPC_IS_ACTIVATED(rovr))
741 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
742 rovr->tk_flags |= RPC_TASK_KILLED;
743 rpc_exit(rovr, -EIO);
744 if (RPC_IS_QUEUED(rovr))
745 rpc_wake_up_queued_task(rovr->tk_waitqueue,
749 spin_unlock(&clnt->cl_lock);
751 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
754 * Properly shut down an RPC client, terminating all outstanding
757 void rpc_shutdown_client(struct rpc_clnt *clnt)
761 dprintk_rcu("RPC: shutting down %s client for %s\n",
762 clnt->cl_program->name,
763 rcu_dereference(clnt->cl_xprt)->servername);
765 while (!list_empty(&clnt->cl_tasks)) {
766 rpc_killall_tasks(clnt);
767 wait_event_timeout(destroy_wait,
768 list_empty(&clnt->cl_tasks), 1*HZ);
771 rpc_release_client(clnt);
773 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
778 static struct rpc_clnt *
779 rpc_free_client(struct rpc_clnt *clnt)
781 struct rpc_clnt *parent = NULL;
783 dprintk_rcu("RPC: destroying %s client for %s\n",
784 clnt->cl_program->name,
785 rcu_dereference(clnt->cl_xprt)->servername);
786 if (clnt->cl_parent != clnt)
787 parent = clnt->cl_parent;
788 rpc_clnt_debugfs_unregister(clnt);
789 rpc_clnt_remove_pipedir(clnt);
790 rpc_unregister_client(clnt);
791 rpc_free_iostats(clnt->cl_metrics);
792 clnt->cl_metrics = NULL;
793 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
803 static struct rpc_clnt *
804 rpc_free_auth(struct rpc_clnt *clnt)
806 if (clnt->cl_auth == NULL)
807 return rpc_free_client(clnt);
810 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
811 * release remaining GSS contexts. This mechanism ensures
812 * that it can do so safely.
814 atomic_inc(&clnt->cl_count);
815 rpcauth_release(clnt->cl_auth);
816 clnt->cl_auth = NULL;
817 if (atomic_dec_and_test(&clnt->cl_count))
818 return rpc_free_client(clnt);
823 * Release reference to the RPC client
826 rpc_release_client(struct rpc_clnt *clnt)
828 dprintk("RPC: rpc_release_client(%p)\n", clnt);
831 if (list_empty(&clnt->cl_tasks))
832 wake_up(&destroy_wait);
833 if (!atomic_dec_and_test(&clnt->cl_count))
835 clnt = rpc_free_auth(clnt);
836 } while (clnt != NULL);
838 EXPORT_SYMBOL_GPL(rpc_release_client);
841 * rpc_bind_new_program - bind a new RPC program to an existing client
842 * @old: old rpc_client
843 * @program: rpc program to set
844 * @vers: rpc program version
846 * Clones the rpc client and sets up a new RPC program. This is mainly
847 * of use for enabling different RPC programs to share the same transport.
848 * The Sun NFSv2/v3 ACL protocol can do this.
850 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
851 const struct rpc_program *program,
854 struct rpc_create_args args = {
856 .prognumber = program->number,
858 .authflavor = old->cl_auth->au_flavor,
860 struct rpc_clnt *clnt;
863 clnt = __rpc_clone_client(&args, old);
866 err = rpc_ping(clnt);
868 rpc_shutdown_client(clnt);
874 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
876 void rpc_task_release_client(struct rpc_task *task)
878 struct rpc_clnt *clnt = task->tk_client;
881 /* Remove from client task list */
882 spin_lock(&clnt->cl_lock);
883 list_del(&task->tk_task);
884 spin_unlock(&clnt->cl_lock);
885 task->tk_client = NULL;
887 rpc_release_client(clnt);
892 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
895 rpc_task_release_client(task);
896 task->tk_client = clnt;
897 atomic_inc(&clnt->cl_count);
898 if (clnt->cl_softrtry)
899 task->tk_flags |= RPC_TASK_SOFT;
900 if (clnt->cl_noretranstimeo)
901 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
902 if (atomic_read(&clnt->cl_swapper))
903 task->tk_flags |= RPC_TASK_SWAPPER;
904 /* Add to the client's list of all tasks */
905 spin_lock(&clnt->cl_lock);
906 list_add_tail(&task->tk_task, &clnt->cl_tasks);
907 spin_unlock(&clnt->cl_lock);
911 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
913 rpc_task_release_client(task);
914 rpc_task_set_client(task, clnt);
916 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
920 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
923 task->tk_msg.rpc_proc = msg->rpc_proc;
924 task->tk_msg.rpc_argp = msg->rpc_argp;
925 task->tk_msg.rpc_resp = msg->rpc_resp;
926 if (msg->rpc_cred != NULL)
927 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
932 * Default callback for async RPC calls
935 rpc_default_callback(struct rpc_task *task, void *data)
939 static const struct rpc_call_ops rpc_default_ops = {
940 .rpc_call_done = rpc_default_callback,
944 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
945 * @task_setup_data: pointer to task initialisation data
947 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
949 struct rpc_task *task;
951 task = rpc_new_task(task_setup_data);
955 rpc_task_set_client(task, task_setup_data->rpc_client);
956 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
958 if (task->tk_action == NULL)
959 rpc_call_start(task);
961 atomic_inc(&task->tk_count);
966 EXPORT_SYMBOL_GPL(rpc_run_task);
969 * rpc_call_sync - Perform a synchronous RPC call
970 * @clnt: pointer to RPC client
971 * @msg: RPC call parameters
972 * @flags: RPC call flags
974 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
976 struct rpc_task *task;
977 struct rpc_task_setup task_setup_data = {
980 .callback_ops = &rpc_default_ops,
985 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
986 if (flags & RPC_TASK_ASYNC) {
987 rpc_release_calldata(task_setup_data.callback_ops,
988 task_setup_data.callback_data);
992 task = rpc_run_task(&task_setup_data);
994 return PTR_ERR(task);
995 status = task->tk_status;
999 EXPORT_SYMBOL_GPL(rpc_call_sync);
1002 * rpc_call_async - Perform an asynchronous RPC call
1003 * @clnt: pointer to RPC client
1004 * @msg: RPC call parameters
1005 * @flags: RPC call flags
1006 * @tk_ops: RPC call ops
1007 * @data: user call data
1010 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1011 const struct rpc_call_ops *tk_ops, void *data)
1013 struct rpc_task *task;
1014 struct rpc_task_setup task_setup_data = {
1017 .callback_ops = tk_ops,
1018 .callback_data = data,
1019 .flags = flags|RPC_TASK_ASYNC,
1022 task = rpc_run_task(&task_setup_data);
1024 return PTR_ERR(task);
1028 EXPORT_SYMBOL_GPL(rpc_call_async);
1030 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1032 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1033 * rpc_execute against it
1036 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1038 struct rpc_task *task;
1039 struct xdr_buf *xbufp = &req->rq_snd_buf;
1040 struct rpc_task_setup task_setup_data = {
1041 .callback_ops = &rpc_default_ops,
1042 .flags = RPC_TASK_SOFTCONN,
1045 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1047 * Create an rpc_task to send the data
1049 task = rpc_new_task(&task_setup_data);
1051 xprt_free_bc_request(req);
1054 task->tk_rqstp = req;
1057 * Set up the xdr_buf length.
1058 * This also indicates that the buffer is XDR encoded already.
1060 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
1061 xbufp->tail[0].iov_len;
1063 task->tk_action = call_bc_transmit;
1064 atomic_inc(&task->tk_count);
1065 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1069 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1072 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1075 rpc_call_start(struct rpc_task *task)
1077 task->tk_action = call_start;
1079 EXPORT_SYMBOL_GPL(rpc_call_start);
1082 * rpc_peeraddr - extract remote peer address from clnt's xprt
1083 * @clnt: RPC client structure
1084 * @buf: target buffer
1085 * @bufsize: length of target buffer
1087 * Returns the number of bytes that are actually in the stored address.
1089 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1092 struct rpc_xprt *xprt;
1095 xprt = rcu_dereference(clnt->cl_xprt);
1097 bytes = xprt->addrlen;
1098 if (bytes > bufsize)
1100 memcpy(buf, &xprt->addr, bytes);
1105 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1108 * rpc_peeraddr2str - return remote peer address in printable format
1109 * @clnt: RPC client structure
1110 * @format: address format
1112 * NB: the lifetime of the memory referenced by the returned pointer is
1113 * the same as the rpc_xprt itself. As long as the caller uses this
1114 * pointer, it must hold the RCU read lock.
1116 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1117 enum rpc_display_format_t format)
1119 struct rpc_xprt *xprt;
1121 xprt = rcu_dereference(clnt->cl_xprt);
1123 if (xprt->address_strings[format] != NULL)
1124 return xprt->address_strings[format];
1126 return "unprintable";
1128 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1130 static const struct sockaddr_in rpc_inaddr_loopback = {
1131 .sin_family = AF_INET,
1132 .sin_addr.s_addr = htonl(INADDR_ANY),
1135 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1136 .sin6_family = AF_INET6,
1137 .sin6_addr = IN6ADDR_ANY_INIT,
1141 * Try a getsockname() on a connected datagram socket. Using a
1142 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1143 * This conserves the ephemeral port number space.
1145 * Returns zero and fills in "buf" if successful; otherwise, a
1146 * negative errno is returned.
1148 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1149 struct sockaddr *buf, int buflen)
1151 struct socket *sock;
1154 err = __sock_create(net, sap->sa_family,
1155 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1157 dprintk("RPC: can't create UDP socket (%d)\n", err);
1161 switch (sap->sa_family) {
1163 err = kernel_bind(sock,
1164 (struct sockaddr *)&rpc_inaddr_loopback,
1165 sizeof(rpc_inaddr_loopback));
1168 err = kernel_bind(sock,
1169 (struct sockaddr *)&rpc_in6addr_loopback,
1170 sizeof(rpc_in6addr_loopback));
1173 err = -EAFNOSUPPORT;
1177 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1181 err = kernel_connect(sock, sap, salen, 0);
1183 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1187 err = kernel_getsockname(sock, buf, &buflen);
1189 dprintk("RPC: getsockname failed (%d)\n", err);
1194 if (buf->sa_family == AF_INET6) {
1195 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1196 sin6->sin6_scope_id = 0;
1198 dprintk("RPC: %s succeeded\n", __func__);
1207 * Scraping a connected socket failed, so we don't have a useable
1208 * local address. Fallback: generate an address that will prevent
1209 * the server from calling us back.
1211 * Returns zero and fills in "buf" if successful; otherwise, a
1212 * negative errno is returned.
1214 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1218 if (buflen < sizeof(rpc_inaddr_loopback))
1220 memcpy(buf, &rpc_inaddr_loopback,
1221 sizeof(rpc_inaddr_loopback));
1224 if (buflen < sizeof(rpc_in6addr_loopback))
1226 memcpy(buf, &rpc_in6addr_loopback,
1227 sizeof(rpc_in6addr_loopback));
1229 dprintk("RPC: %s: address family not supported\n",
1231 return -EAFNOSUPPORT;
1233 dprintk("RPC: %s: succeeded\n", __func__);
1238 * rpc_localaddr - discover local endpoint address for an RPC client
1239 * @clnt: RPC client structure
1240 * @buf: target buffer
1241 * @buflen: size of target buffer, in bytes
1243 * Returns zero and fills in "buf" and "buflen" if successful;
1244 * otherwise, a negative errno is returned.
1246 * This works even if the underlying transport is not currently connected,
1247 * or if the upper layer never previously provided a source address.
1249 * The result of this function call is transient: multiple calls in
1250 * succession may give different results, depending on how local
1251 * networking configuration changes over time.
1253 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1255 struct sockaddr_storage address;
1256 struct sockaddr *sap = (struct sockaddr *)&address;
1257 struct rpc_xprt *xprt;
1263 xprt = rcu_dereference(clnt->cl_xprt);
1264 salen = xprt->addrlen;
1265 memcpy(sap, &xprt->addr, salen);
1266 net = get_net(xprt->xprt_net);
1269 rpc_set_port(sap, 0);
1270 err = rpc_sockname(net, sap, salen, buf, buflen);
1273 /* Couldn't discover local address, return ANYADDR */
1274 return rpc_anyaddr(sap->sa_family, buf, buflen);
1277 EXPORT_SYMBOL_GPL(rpc_localaddr);
1280 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1282 struct rpc_xprt *xprt;
1285 xprt = rcu_dereference(clnt->cl_xprt);
1286 if (xprt->ops->set_buffer_size)
1287 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1290 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1293 * rpc_protocol - Get transport protocol number for an RPC client
1294 * @clnt: RPC client to query
1297 int rpc_protocol(struct rpc_clnt *clnt)
1302 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1306 EXPORT_SYMBOL_GPL(rpc_protocol);
1309 * rpc_net_ns - Get the network namespace for this RPC client
1310 * @clnt: RPC client to query
1313 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1318 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1322 EXPORT_SYMBOL_GPL(rpc_net_ns);
1325 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1326 * @clnt: RPC client to query
1328 * For stream transports, this is one RPC record fragment (see RFC
1329 * 1831), as we don't support multi-record requests yet. For datagram
1330 * transports, this is the size of an IP packet minus the IP, UDP, and
1333 size_t rpc_max_payload(struct rpc_clnt *clnt)
1338 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1342 EXPORT_SYMBOL_GPL(rpc_max_payload);
1345 * rpc_get_timeout - Get timeout for transport in units of HZ
1346 * @clnt: RPC client to query
1348 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1353 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1357 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1360 * rpc_force_rebind - force transport to check that remote port is unchanged
1361 * @clnt: client to rebind
1364 void rpc_force_rebind(struct rpc_clnt *clnt)
1366 if (clnt->cl_autobind) {
1368 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1372 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1375 * Restart an (async) RPC call from the call_prepare state.
1376 * Usually called from within the exit handler.
1379 rpc_restart_call_prepare(struct rpc_task *task)
1381 if (RPC_ASSASSINATED(task))
1383 task->tk_action = call_start;
1384 task->tk_status = 0;
1385 if (task->tk_ops->rpc_call_prepare != NULL)
1386 task->tk_action = rpc_prepare_task;
1389 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1392 * Restart an (async) RPC call. Usually called from within the
1396 rpc_restart_call(struct rpc_task *task)
1398 if (RPC_ASSASSINATED(task))
1400 task->tk_action = call_start;
1401 task->tk_status = 0;
1404 EXPORT_SYMBOL_GPL(rpc_restart_call);
1406 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
1408 *rpc_proc_name(const struct rpc_task *task)
1410 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1414 return proc->p_name;
1425 * Other FSM states can be visited zero or more times, but
1426 * this state is visited exactly once for each RPC.
1429 call_start(struct rpc_task *task)
1431 struct rpc_clnt *clnt = task->tk_client;
1433 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1434 clnt->cl_program->name, clnt->cl_vers,
1435 rpc_proc_name(task),
1436 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1438 /* Increment call count */
1439 task->tk_msg.rpc_proc->p_count++;
1440 clnt->cl_stats->rpccnt++;
1441 task->tk_action = call_reserve;
1445 * 1. Reserve an RPC call slot
1448 call_reserve(struct rpc_task *task)
1450 dprint_status(task);
1452 task->tk_status = 0;
1453 task->tk_action = call_reserveresult;
1457 static void call_retry_reserve(struct rpc_task *task);
1460 * 1b. Grok the result of xprt_reserve()
1463 call_reserveresult(struct rpc_task *task)
1465 int status = task->tk_status;
1467 dprint_status(task);
1470 * After a call to xprt_reserve(), we must have either
1471 * a request slot or else an error status.
1473 task->tk_status = 0;
1475 if (task->tk_rqstp) {
1476 task->tk_action = call_refresh;
1480 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1482 rpc_exit(task, -EIO);
1487 * Even though there was an error, we may have acquired
1488 * a request slot somehow. Make sure not to leak it.
1490 if (task->tk_rqstp) {
1491 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1498 rpc_delay(task, HZ >> 2);
1499 case -EAGAIN: /* woken up; retry */
1500 task->tk_action = call_retry_reserve;
1502 case -EIO: /* probably a shutdown */
1505 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1509 rpc_exit(task, status);
1513 * 1c. Retry reserving an RPC call slot
1516 call_retry_reserve(struct rpc_task *task)
1518 dprint_status(task);
1520 task->tk_status = 0;
1521 task->tk_action = call_reserveresult;
1522 xprt_retry_reserve(task);
1526 * 2. Bind and/or refresh the credentials
1529 call_refresh(struct rpc_task *task)
1531 dprint_status(task);
1533 task->tk_action = call_refreshresult;
1534 task->tk_status = 0;
1535 task->tk_client->cl_stats->rpcauthrefresh++;
1536 rpcauth_refreshcred(task);
1540 * 2a. Process the results of a credential refresh
1543 call_refreshresult(struct rpc_task *task)
1545 int status = task->tk_status;
1547 dprint_status(task);
1549 task->tk_status = 0;
1550 task->tk_action = call_refresh;
1553 if (rpcauth_uptodatecred(task)) {
1554 task->tk_action = call_allocate;
1557 /* Use rate-limiting and a max number of retries if refresh
1558 * had status 0 but failed to update the cred.
1561 rpc_delay(task, 3*HZ);
1565 if (!task->tk_cred_retry)
1567 task->tk_cred_retry--;
1568 dprintk("RPC: %5u %s: retry refresh creds\n",
1569 task->tk_pid, __func__);
1572 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1573 task->tk_pid, __func__, status);
1574 rpc_exit(task, status);
1578 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1579 * (Note: buffer memory is freed in xprt_release).
1582 call_allocate(struct rpc_task *task)
1584 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1585 struct rpc_rqst *req = task->tk_rqstp;
1586 struct rpc_xprt *xprt = req->rq_xprt;
1587 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1589 dprint_status(task);
1591 task->tk_status = 0;
1592 task->tk_action = call_bind;
1597 if (proc->p_proc != 0) {
1598 BUG_ON(proc->p_arglen == 0);
1599 if (proc->p_decode != NULL)
1600 BUG_ON(proc->p_replen == 0);
1604 * Calculate the size (in quads) of the RPC call
1605 * and reply headers, and convert both values
1608 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1609 req->rq_callsize <<= 2;
1610 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1611 req->rq_rcvsize <<= 2;
1613 req->rq_buffer = xprt->ops->buf_alloc(task,
1614 req->rq_callsize + req->rq_rcvsize);
1615 if (req->rq_buffer != NULL)
1617 xprt_inject_disconnect(xprt);
1619 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1621 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1622 task->tk_action = call_allocate;
1623 rpc_delay(task, HZ>>4);
1627 rpc_exit(task, -ERESTARTSYS);
1631 rpc_task_need_encode(struct rpc_task *task)
1633 return task->tk_rqstp->rq_snd_buf.len == 0;
1637 rpc_task_force_reencode(struct rpc_task *task)
1639 task->tk_rqstp->rq_snd_buf.len = 0;
1640 task->tk_rqstp->rq_bytes_sent = 0;
1644 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1646 buf->head[0].iov_base = start;
1647 buf->head[0].iov_len = len;
1648 buf->tail[0].iov_len = 0;
1656 * 3. Encode arguments of an RPC call
1659 rpc_xdr_encode(struct rpc_task *task)
1661 struct rpc_rqst *req = task->tk_rqstp;
1665 dprint_status(task);
1667 rpc_xdr_buf_init(&req->rq_snd_buf,
1670 rpc_xdr_buf_init(&req->rq_rcv_buf,
1671 (char *)req->rq_buffer + req->rq_callsize,
1674 p = rpc_encode_header(task);
1676 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1677 rpc_exit(task, -EIO);
1681 encode = task->tk_msg.rpc_proc->p_encode;
1685 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1686 task->tk_msg.rpc_argp);
1690 * 4. Get the server port number if not yet set
1693 call_bind(struct rpc_task *task)
1695 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1697 dprint_status(task);
1699 task->tk_action = call_connect;
1700 if (!xprt_bound(xprt)) {
1701 task->tk_action = call_bind_status;
1702 task->tk_timeout = xprt->bind_timeout;
1703 xprt->ops->rpcbind(task);
1708 * 4a. Sort out bind result
1711 call_bind_status(struct rpc_task *task)
1715 if (task->tk_status >= 0) {
1716 dprint_status(task);
1717 task->tk_status = 0;
1718 task->tk_action = call_connect;
1722 trace_rpc_bind_status(task);
1723 switch (task->tk_status) {
1725 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1726 rpc_delay(task, HZ >> 2);
1729 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1730 "unavailable\n", task->tk_pid);
1731 /* fail immediately if this is an RPC ping */
1732 if (task->tk_msg.rpc_proc->p_proc == 0) {
1733 status = -EOPNOTSUPP;
1736 if (task->tk_rebind_retry == 0)
1738 task->tk_rebind_retry--;
1739 rpc_delay(task, 3*HZ);
1742 dprintk("RPC: %5u rpcbind request timed out\n",
1746 /* server doesn't support any rpcbind version we know of */
1747 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1750 case -EPROTONOSUPPORT:
1751 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1754 case -ECONNREFUSED: /* connection problems */
1763 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1764 task->tk_pid, task->tk_status);
1765 if (!RPC_IS_SOFTCONN(task)) {
1766 rpc_delay(task, 5*HZ);
1769 status = task->tk_status;
1772 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1773 task->tk_pid, -task->tk_status);
1776 rpc_exit(task, status);
1780 task->tk_status = 0;
1781 task->tk_action = call_timeout;
1785 * 4b. Connect to the RPC server
1788 call_connect(struct rpc_task *task)
1790 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1792 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1794 (xprt_connected(xprt) ? "is" : "is not"));
1796 task->tk_action = call_transmit;
1797 if (!xprt_connected(xprt)) {
1798 task->tk_action = call_connect_status;
1799 if (task->tk_status < 0)
1801 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1802 rpc_exit(task, -ENOTCONN);
1810 * 4c. Sort out connect result
1813 call_connect_status(struct rpc_task *task)
1815 struct rpc_clnt *clnt = task->tk_client;
1816 int status = task->tk_status;
1818 dprint_status(task);
1820 trace_rpc_connect_status(task, status);
1821 task->tk_status = 0;
1831 if (RPC_IS_SOFTCONN(task))
1833 /* retry with existing socket, after a delay */
1834 rpc_delay(task, 3*HZ);
1836 /* Check for timeouts before looping back to call_bind */
1838 task->tk_action = call_timeout;
1841 clnt->cl_stats->netreconn++;
1842 task->tk_action = call_transmit;
1845 rpc_exit(task, status);
1849 * 5. Transmit the RPC request, and wait for reply
1852 call_transmit(struct rpc_task *task)
1854 int is_retrans = RPC_WAS_SENT(task);
1856 dprint_status(task);
1858 task->tk_action = call_status;
1859 if (task->tk_status < 0)
1861 if (!xprt_prepare_transmit(task))
1863 task->tk_action = call_transmit_status;
1864 /* Encode here so that rpcsec_gss can use correct sequence number. */
1865 if (rpc_task_need_encode(task)) {
1866 rpc_xdr_encode(task);
1867 /* Did the encode result in an error condition? */
1868 if (task->tk_status != 0) {
1869 /* Was the error nonfatal? */
1870 if (task->tk_status == -EAGAIN)
1871 rpc_delay(task, HZ >> 4);
1873 rpc_exit(task, task->tk_status);
1877 xprt_transmit(task);
1878 if (task->tk_status < 0)
1881 task->tk_client->cl_stats->rpcretrans++;
1883 * On success, ensure that we call xprt_end_transmit() before sleeping
1884 * in order to allow access to the socket to other RPC requests.
1886 call_transmit_status(task);
1887 if (rpc_reply_expected(task))
1889 task->tk_action = rpc_exit_task;
1890 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1894 * 5a. Handle cleanup after a transmission
1897 call_transmit_status(struct rpc_task *task)
1899 task->tk_action = call_status;
1902 * Common case: success. Force the compiler to put this
1905 if (task->tk_status == 0) {
1906 xprt_end_transmit(task);
1907 rpc_task_force_reencode(task);
1911 switch (task->tk_status) {
1916 dprint_status(task);
1917 xprt_end_transmit(task);
1918 rpc_task_force_reencode(task);
1921 * Special cases: if we've been waiting on the
1922 * socket's write_space() callback, or if the
1923 * socket just returned a connection error,
1924 * then hold onto the transport lock.
1931 if (RPC_IS_SOFTCONN(task)) {
1932 xprt_end_transmit(task);
1933 rpc_exit(task, task->tk_status);
1941 rpc_task_force_reencode(task);
1945 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1947 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1948 * addition, disconnect on connectivity errors.
1951 call_bc_transmit(struct rpc_task *task)
1953 struct rpc_rqst *req = task->tk_rqstp;
1955 if (!xprt_prepare_transmit(task))
1958 if (task->tk_status < 0) {
1959 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1960 "error: %d\n", task->tk_status);
1963 if (req->rq_connect_cookie != req->rq_xprt->connect_cookie)
1964 req->rq_bytes_sent = 0;
1966 xprt_transmit(task);
1968 if (task->tk_status == -EAGAIN)
1971 xprt_end_transmit(task);
1972 dprint_status(task);
1973 switch (task->tk_status) {
1987 * Problem reaching the server. Disconnect and let the
1988 * forechannel reestablish the connection. The server will
1989 * have to retransmit the backchannel request and we'll
1990 * reprocess it. Since these ops are idempotent, there's no
1991 * need to cache our reply at this time.
1993 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1994 "error: %d\n", task->tk_status);
1995 xprt_conditional_disconnect(req->rq_xprt,
1996 req->rq_connect_cookie);
2000 * We were unable to reply and will have to drop the
2001 * request. The server should reconnect and retransmit.
2003 WARN_ON_ONCE(task->tk_status == -EAGAIN);
2004 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2005 "error: %d\n", task->tk_status);
2008 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
2010 task->tk_action = rpc_exit_task;
2013 req->rq_connect_cookie = req->rq_xprt->connect_cookie;
2015 task->tk_status = 0;
2017 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
2020 * 6. Sort out the RPC call status
2023 call_status(struct rpc_task *task)
2025 struct rpc_clnt *clnt = task->tk_client;
2026 struct rpc_rqst *req = task->tk_rqstp;
2029 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
2030 task->tk_status = req->rq_reply_bytes_recvd;
2032 dprint_status(task);
2034 status = task->tk_status;
2036 task->tk_action = call_decode;
2040 trace_rpc_call_status(task);
2041 task->tk_status = 0;
2047 if (RPC_IS_SOFTCONN(task)) {
2048 rpc_exit(task, status);
2052 * Delay any retries for 3 seconds, then handle as if it
2055 rpc_delay(task, 3*HZ);
2057 task->tk_action = call_timeout;
2058 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
2059 && task->tk_client->cl_discrtry)
2060 xprt_conditional_disconnect(req->rq_xprt,
2061 req->rq_connect_cookie);
2066 rpc_force_rebind(clnt);
2068 rpc_delay(task, 3*HZ);
2071 task->tk_action = call_bind;
2074 rpc_delay(task, HZ>>2);
2076 task->tk_action = call_transmit;
2079 /* shutdown or soft timeout */
2080 rpc_exit(task, status);
2083 if (clnt->cl_chatty)
2084 printk("%s: RPC call returned error %d\n",
2085 clnt->cl_program->name, -status);
2086 rpc_exit(task, status);
2091 * 6a. Handle RPC timeout
2092 * We do not release the request slot, so we keep using the
2093 * same XID for all retransmits.
2096 call_timeout(struct rpc_task *task)
2098 struct rpc_clnt *clnt = task->tk_client;
2100 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
2101 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
2105 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2106 task->tk_timeouts++;
2108 if (RPC_IS_SOFTCONN(task)) {
2109 rpc_exit(task, -ETIMEDOUT);
2112 if (RPC_IS_SOFT(task)) {
2113 if (clnt->cl_chatty) {
2115 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
2116 clnt->cl_program->name,
2117 rcu_dereference(clnt->cl_xprt)->servername);
2120 if (task->tk_flags & RPC_TASK_TIMEOUT)
2121 rpc_exit(task, -ETIMEDOUT);
2123 rpc_exit(task, -EIO);
2127 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2128 task->tk_flags |= RPC_CALL_MAJORSEEN;
2129 if (clnt->cl_chatty) {
2131 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
2132 clnt->cl_program->name,
2133 rcu_dereference(clnt->cl_xprt)->servername);
2137 rpc_force_rebind(clnt);
2139 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2140 * event? RFC2203 requires the server to drop all such requests.
2142 rpcauth_invalcred(task);
2145 task->tk_action = call_bind;
2146 task->tk_status = 0;
2150 * 7. Decode the RPC reply
2153 call_decode(struct rpc_task *task)
2155 struct rpc_clnt *clnt = task->tk_client;
2156 struct rpc_rqst *req = task->tk_rqstp;
2157 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
2160 dprint_status(task);
2162 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2163 if (clnt->cl_chatty) {
2165 printk(KERN_NOTICE "%s: server %s OK\n",
2166 clnt->cl_program->name,
2167 rcu_dereference(clnt->cl_xprt)->servername);
2170 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2174 * Ensure that we see all writes made by xprt_complete_rqst()
2175 * before it changed req->rq_reply_bytes_recvd.
2178 req->rq_rcv_buf.len = req->rq_private_buf.len;
2180 /* Check that the softirq receive buffer is valid */
2181 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2182 sizeof(req->rq_rcv_buf)) != 0);
2184 if (req->rq_rcv_buf.len < 12) {
2185 if (!RPC_IS_SOFT(task)) {
2186 task->tk_action = call_bind;
2189 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2190 clnt->cl_program->name, task->tk_status);
2191 task->tk_action = call_timeout;
2195 p = rpc_verify_header(task);
2197 if (p == ERR_PTR(-EAGAIN))
2202 task->tk_action = rpc_exit_task;
2205 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2206 task->tk_msg.rpc_resp);
2208 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2212 task->tk_status = 0;
2213 /* Note: rpc_verify_header() may have freed the RPC slot */
2214 if (task->tk_rqstp == req) {
2215 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2216 if (task->tk_client->cl_discrtry)
2217 xprt_conditional_disconnect(req->rq_xprt,
2218 req->rq_connect_cookie);
2223 rpc_encode_header(struct rpc_task *task)
2225 struct rpc_clnt *clnt = task->tk_client;
2226 struct rpc_rqst *req = task->tk_rqstp;
2227 __be32 *p = req->rq_svec[0].iov_base;
2229 /* FIXME: check buffer size? */
2231 p = xprt_skip_transport_header(req->rq_xprt, p);
2232 *p++ = req->rq_xid; /* XID */
2233 *p++ = htonl(RPC_CALL); /* CALL */
2234 *p++ = htonl(RPC_VERSION); /* RPC version */
2235 *p++ = htonl(clnt->cl_prog); /* program number */
2236 *p++ = htonl(clnt->cl_vers); /* program version */
2237 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2238 p = rpcauth_marshcred(task, p);
2239 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2244 rpc_verify_header(struct rpc_task *task)
2246 struct rpc_clnt *clnt = task->tk_client;
2247 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2248 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2249 __be32 *p = iov->iov_base;
2251 int error = -EACCES;
2253 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2254 /* RFC-1014 says that the representation of XDR data must be a
2255 * multiple of four bytes
2256 * - if it isn't pointer subtraction in the NFS client may give
2259 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2260 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2261 task->tk_rqstp->rq_rcv_buf.len);
2268 p += 1; /* skip XID */
2269 if ((n = ntohl(*p++)) != RPC_REPLY) {
2270 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2271 task->tk_pid, __func__, n);
2276 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2279 switch ((n = ntohl(*p++))) {
2280 case RPC_AUTH_ERROR:
2283 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2284 task->tk_pid, __func__);
2285 error = -EPROTONOSUPPORT;
2288 dprintk("RPC: %5u %s: RPC call rejected, "
2289 "unknown error: %x\n",
2290 task->tk_pid, __func__, n);
2296 switch ((n = ntohl(*p++))) {
2297 case RPC_AUTH_REJECTEDCRED:
2298 case RPC_AUTH_REJECTEDVERF:
2299 case RPCSEC_GSS_CREDPROBLEM:
2300 case RPCSEC_GSS_CTXPROBLEM:
2301 if (!task->tk_cred_retry)
2303 task->tk_cred_retry--;
2304 dprintk("RPC: %5u %s: retry stale creds\n",
2305 task->tk_pid, __func__);
2306 rpcauth_invalcred(task);
2307 /* Ensure we obtain a new XID! */
2309 task->tk_action = call_reserve;
2311 case RPC_AUTH_BADCRED:
2312 case RPC_AUTH_BADVERF:
2313 /* possibly garbled cred/verf? */
2314 if (!task->tk_garb_retry)
2316 task->tk_garb_retry--;
2317 dprintk("RPC: %5u %s: retry garbled creds\n",
2318 task->tk_pid, __func__);
2319 task->tk_action = call_bind;
2321 case RPC_AUTH_TOOWEAK:
2323 printk(KERN_NOTICE "RPC: server %s requires stronger "
2324 "authentication.\n",
2325 rcu_dereference(clnt->cl_xprt)->servername);
2329 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2330 task->tk_pid, __func__, n);
2333 dprintk("RPC: %5u %s: call rejected %d\n",
2334 task->tk_pid, __func__, n);
2337 p = rpcauth_checkverf(task, p);
2340 dprintk("RPC: %5u %s: auth check failed with %d\n",
2341 task->tk_pid, __func__, error);
2342 goto out_garbage; /* bad verifier, retry */
2344 len = p - (__be32 *)iov->iov_base - 1;
2347 switch ((n = ntohl(*p++))) {
2350 case RPC_PROG_UNAVAIL:
2351 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2352 "by server %s\n", task->tk_pid, __func__,
2353 (unsigned int)clnt->cl_prog,
2354 rcu_dereference(clnt->cl_xprt)->servername);
2355 error = -EPFNOSUPPORT;
2357 case RPC_PROG_MISMATCH:
2358 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2359 "by server %s\n", task->tk_pid, __func__,
2360 (unsigned int)clnt->cl_prog,
2361 (unsigned int)clnt->cl_vers,
2362 rcu_dereference(clnt->cl_xprt)->servername);
2363 error = -EPROTONOSUPPORT;
2365 case RPC_PROC_UNAVAIL:
2366 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2367 "version %u on server %s\n",
2368 task->tk_pid, __func__,
2369 rpc_proc_name(task),
2370 clnt->cl_prog, clnt->cl_vers,
2371 rcu_dereference(clnt->cl_xprt)->servername);
2372 error = -EOPNOTSUPP;
2374 case RPC_GARBAGE_ARGS:
2375 dprintk("RPC: %5u %s: server saw garbage\n",
2376 task->tk_pid, __func__);
2379 dprintk("RPC: %5u %s: server accept status: %x\n",
2380 task->tk_pid, __func__, n);
2385 clnt->cl_stats->rpcgarbage++;
2386 if (task->tk_garb_retry) {
2387 task->tk_garb_retry--;
2388 dprintk("RPC: %5u %s: retrying\n",
2389 task->tk_pid, __func__);
2390 task->tk_action = call_bind;
2392 return ERR_PTR(-EAGAIN);
2395 rpc_exit(task, error);
2396 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2398 return ERR_PTR(error);
2400 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2405 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2409 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2414 static struct rpc_procinfo rpcproc_null = {
2415 .p_encode = rpcproc_encode_null,
2416 .p_decode = rpcproc_decode_null,
2419 static int rpc_ping(struct rpc_clnt *clnt)
2421 struct rpc_message msg = {
2422 .rpc_proc = &rpcproc_null,
2425 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2426 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2427 put_rpccred(msg.rpc_cred);
2431 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2433 struct rpc_message msg = {
2434 .rpc_proc = &rpcproc_null,
2437 struct rpc_task_setup task_setup_data = {
2439 .rpc_message = &msg,
2440 .callback_ops = &rpc_default_ops,
2443 return rpc_run_task(&task_setup_data);
2445 EXPORT_SYMBOL_GPL(rpc_call_null);
2447 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
2448 static void rpc_show_header(void)
2450 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2451 "-timeout ---ops--\n");
2454 static void rpc_show_task(const struct rpc_clnt *clnt,
2455 const struct rpc_task *task)
2457 const char *rpc_waitq = "none";
2459 if (RPC_IS_QUEUED(task))
2460 rpc_waitq = rpc_qname(task->tk_waitqueue);
2462 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2463 task->tk_pid, task->tk_flags, task->tk_status,
2464 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2465 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2466 task->tk_action, rpc_waitq);
2469 void rpc_show_tasks(struct net *net)
2471 struct rpc_clnt *clnt;
2472 struct rpc_task *task;
2474 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2476 spin_lock(&sn->rpc_client_lock);
2477 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2478 spin_lock(&clnt->cl_lock);
2479 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2484 rpc_show_task(clnt, task);
2486 spin_unlock(&clnt->cl_lock);
2488 spin_unlock(&sn->rpc_client_lock);
2492 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
2494 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
2497 struct rpc_xprt *xprt;
2499 if (atomic_inc_return(&clnt->cl_swapper) == 1) {
2502 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
2506 * If we didn't get a reference, then we likely are
2507 * racing with a migration event. Wait for a grace
2508 * period and try again.
2514 ret = xprt_enable_swap(xprt);
2519 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
2522 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
2524 struct rpc_xprt *xprt;
2526 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) {
2529 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
2533 * If we didn't get a reference, then we likely are
2534 * racing with a migration event. Wait for a grace
2535 * period and try again.
2541 xprt_disable_swap(xprt);
2545 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
2546 #endif /* CONFIG_SUNRPC_SWAP */