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 * NB: BSD uses a more intelligent approach to guessing when a request
17 * or reply has been lost by keeping the RTO estimate for each procedure.
18 * We currently make do with a constant timeout value.
20 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
21 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
24 #include <asm/system.h>
26 #include <linux/module.h>
27 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/smp_lock.h>
31 #include <linux/utsname.h>
32 #include <linux/workqueue.h>
33 #include <linux/in6.h>
35 #include <linux/sunrpc/clnt.h>
36 #include <linux/sunrpc/rpc_pipe_fs.h>
37 #include <linux/sunrpc/metrics.h>
41 # define RPCDBG_FACILITY RPCDBG_CALL
44 #define dprint_status(t) \
45 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
46 __FUNCTION__, t->tk_status)
49 * All RPC clients are linked into this list
51 static LIST_HEAD(all_clients);
52 static DEFINE_SPINLOCK(rpc_client_lock);
54 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
57 static void call_start(struct rpc_task *task);
58 static void call_reserve(struct rpc_task *task);
59 static void call_reserveresult(struct rpc_task *task);
60 static void call_allocate(struct rpc_task *task);
61 static void call_encode(struct rpc_task *task);
62 static void call_decode(struct rpc_task *task);
63 static void call_bind(struct rpc_task *task);
64 static void call_bind_status(struct rpc_task *task);
65 static void call_transmit(struct rpc_task *task);
66 static void call_status(struct rpc_task *task);
67 static void call_transmit_status(struct rpc_task *task);
68 static void call_refresh(struct rpc_task *task);
69 static void call_refreshresult(struct rpc_task *task);
70 static void call_timeout(struct rpc_task *task);
71 static void call_connect(struct rpc_task *task);
72 static void call_connect_status(struct rpc_task *task);
73 static __be32 * call_header(struct rpc_task *task);
74 static __be32 * call_verify(struct rpc_task *task);
76 static int rpc_ping(struct rpc_clnt *clnt, int flags);
78 static void rpc_register_client(struct rpc_clnt *clnt)
80 spin_lock(&rpc_client_lock);
81 list_add(&clnt->cl_clients, &all_clients);
82 spin_unlock(&rpc_client_lock);
85 static void rpc_unregister_client(struct rpc_clnt *clnt)
87 spin_lock(&rpc_client_lock);
88 list_del(&clnt->cl_clients);
89 spin_unlock(&rpc_client_lock);
93 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
95 static uint32_t clntid;
98 clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
99 clnt->cl_dentry = ERR_PTR(-ENOENT);
100 if (dir_name == NULL)
103 clnt->cl_vfsmnt = rpc_get_mount();
104 if (IS_ERR(clnt->cl_vfsmnt))
105 return PTR_ERR(clnt->cl_vfsmnt);
108 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
109 "%s/clnt%x", dir_name,
110 (unsigned int)clntid++);
111 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
112 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
113 if (!IS_ERR(clnt->cl_dentry))
115 error = PTR_ERR(clnt->cl_dentry);
116 if (error != -EEXIST) {
117 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
118 clnt->cl_pathname, error);
125 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
127 struct rpc_program *program = args->program;
128 struct rpc_version *version;
129 struct rpc_clnt *clnt = NULL;
130 struct rpc_auth *auth;
134 /* sanity check the name before trying to print it */
136 len = strlen(args->servername);
137 if (len > RPC_MAXNETNAMELEN)
141 dprintk("RPC: creating %s client for %s (xprt %p)\n",
142 program->name, args->servername, xprt);
151 if (args->version >= program->nrvers)
153 version = program->version[args->version];
158 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
161 clnt->cl_parent = clnt;
163 clnt->cl_server = clnt->cl_inline_name;
164 if (len > sizeof(clnt->cl_inline_name)) {
165 char *buf = kmalloc(len, GFP_KERNEL);
167 clnt->cl_server = buf;
169 len = sizeof(clnt->cl_inline_name);
171 strlcpy(clnt->cl_server, args->servername, len);
173 clnt->cl_xprt = xprt;
174 clnt->cl_procinfo = version->procs;
175 clnt->cl_maxproc = version->nrprocs;
176 clnt->cl_protname = program->name;
177 clnt->cl_prog = program->number;
178 clnt->cl_vers = version->number;
179 clnt->cl_stats = program->stats;
180 clnt->cl_metrics = rpc_alloc_iostats(clnt);
182 if (clnt->cl_metrics == NULL)
184 clnt->cl_program = program;
185 INIT_LIST_HEAD(&clnt->cl_tasks);
186 spin_lock_init(&clnt->cl_lock);
188 if (!xprt_bound(clnt->cl_xprt))
189 clnt->cl_autobind = 1;
191 clnt->cl_rtt = &clnt->cl_rtt_default;
192 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
194 kref_init(&clnt->cl_kref);
196 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
200 auth = rpcauth_create(args->authflavor, clnt);
202 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
208 /* save the nodename */
209 clnt->cl_nodelen = strlen(utsname()->nodename);
210 if (clnt->cl_nodelen > UNX_MAXNODENAME)
211 clnt->cl_nodelen = UNX_MAXNODENAME;
212 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
213 rpc_register_client(clnt);
217 if (!IS_ERR(clnt->cl_dentry)) {
218 rpc_rmdir(clnt->cl_dentry);
222 rpc_free_iostats(clnt->cl_metrics);
224 if (clnt->cl_server != clnt->cl_inline_name)
225 kfree(clnt->cl_server);
236 * rpc_create - create an RPC client and transport with one call
237 * @args: rpc_clnt create argument structure
239 * Creates and initializes an RPC transport and an RPC client.
241 * It can ping the server in order to determine if it is up, and to see if
242 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
243 * this behavior so asynchronous tasks can also use rpc_create.
245 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
247 struct rpc_xprt *xprt;
248 struct rpc_clnt *clnt;
249 struct xprt_create xprtargs = {
250 .ident = args->protocol,
251 .srcaddr = args->saddress,
252 .dstaddr = args->address,
253 .addrlen = args->addrsize,
254 .timeout = args->timeout
258 xprt = xprt_create_transport(&xprtargs);
260 return (struct rpc_clnt *)xprt;
263 * If the caller chooses not to specify a hostname, whip
264 * up a string representation of the passed-in address.
266 if (args->servername == NULL) {
267 servername[0] = '\0';
268 switch (args->address->sa_family) {
270 struct sockaddr_in *sin =
271 (struct sockaddr_in *)args->address;
272 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
273 NIPQUAD(sin->sin_addr.s_addr));
277 struct sockaddr_in6 *sin =
278 (struct sockaddr_in6 *)args->address;
279 snprintf(servername, sizeof(servername), NIP6_FMT,
280 NIP6(sin->sin6_addr));
284 /* caller wants default server name, but
285 * address family isn't recognized. */
286 return ERR_PTR(-EINVAL);
288 args->servername = servername;
291 xprt = xprt_create_transport(&xprtargs);
293 return (struct rpc_clnt *)xprt;
296 * By default, kernel RPC client connects from a reserved port.
297 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
298 * but it is always enabled for rpciod, which handles the connect
302 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
305 clnt = rpc_new_client(args, xprt);
309 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
310 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
312 rpc_shutdown_client(clnt);
317 clnt->cl_softrtry = 1;
318 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
319 clnt->cl_softrtry = 0;
321 if (args->flags & RPC_CLNT_CREATE_INTR)
323 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
324 clnt->cl_autobind = 1;
325 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
326 clnt->cl_discrtry = 1;
330 EXPORT_SYMBOL_GPL(rpc_create);
333 * This function clones the RPC client structure. It allows us to share the
334 * same transport while varying parameters such as the authentication
338 rpc_clone_client(struct rpc_clnt *clnt)
340 struct rpc_clnt *new;
343 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
346 new->cl_parent = clnt;
347 /* Turn off autobind on clones */
348 new->cl_autobind = 0;
349 INIT_LIST_HEAD(&new->cl_tasks);
350 spin_lock_init(&new->cl_lock);
351 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
352 new->cl_metrics = rpc_alloc_iostats(clnt);
353 if (new->cl_metrics == NULL)
355 kref_init(&new->cl_kref);
356 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
360 atomic_inc(&new->cl_auth->au_count);
361 xprt_get(clnt->cl_xprt);
362 kref_get(&clnt->cl_kref);
363 rpc_register_client(new);
367 rpc_free_iostats(new->cl_metrics);
371 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
374 EXPORT_SYMBOL_GPL(rpc_clone_client);
377 * Properly shut down an RPC client, terminating all outstanding
380 void rpc_shutdown_client(struct rpc_clnt *clnt)
382 dprintk("RPC: shutting down %s client for %s\n",
383 clnt->cl_protname, clnt->cl_server);
385 while (!list_empty(&clnt->cl_tasks)) {
386 rpc_killall_tasks(clnt);
387 wait_event_timeout(destroy_wait,
388 list_empty(&clnt->cl_tasks), 1*HZ);
391 rpc_release_client(clnt);
393 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
399 rpc_free_client(struct kref *kref)
401 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
403 dprintk("RPC: destroying %s client for %s\n",
404 clnt->cl_protname, clnt->cl_server);
405 if (!IS_ERR(clnt->cl_dentry)) {
406 rpc_rmdir(clnt->cl_dentry);
409 if (clnt->cl_parent != clnt) {
410 rpc_release_client(clnt->cl_parent);
413 if (clnt->cl_server != clnt->cl_inline_name)
414 kfree(clnt->cl_server);
416 rpc_unregister_client(clnt);
417 rpc_free_iostats(clnt->cl_metrics);
418 clnt->cl_metrics = NULL;
419 xprt_put(clnt->cl_xprt);
428 rpc_free_auth(struct kref *kref)
430 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
432 if (clnt->cl_auth == NULL) {
433 rpc_free_client(kref);
438 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
439 * release remaining GSS contexts. This mechanism ensures
440 * that it can do so safely.
443 rpcauth_release(clnt->cl_auth);
444 clnt->cl_auth = NULL;
445 kref_put(kref, rpc_free_client);
449 * Release reference to the RPC client
452 rpc_release_client(struct rpc_clnt *clnt)
454 dprintk("RPC: rpc_release_client(%p)\n", clnt);
456 if (list_empty(&clnt->cl_tasks))
457 wake_up(&destroy_wait);
458 kref_put(&clnt->cl_kref, rpc_free_auth);
462 * rpc_bind_new_program - bind a new RPC program to an existing client
463 * @old - old rpc_client
464 * @program - rpc program to set
465 * @vers - rpc program version
467 * Clones the rpc client and sets up a new RPC program. This is mainly
468 * of use for enabling different RPC programs to share the same transport.
469 * The Sun NFSv2/v3 ACL protocol can do this.
471 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
472 struct rpc_program *program,
475 struct rpc_clnt *clnt;
476 struct rpc_version *version;
479 BUG_ON(vers >= program->nrvers || !program->version[vers]);
480 version = program->version[vers];
481 clnt = rpc_clone_client(old);
484 clnt->cl_procinfo = version->procs;
485 clnt->cl_maxproc = version->nrprocs;
486 clnt->cl_protname = program->name;
487 clnt->cl_prog = program->number;
488 clnt->cl_vers = version->number;
489 clnt->cl_stats = program->stats;
490 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
492 rpc_shutdown_client(clnt);
498 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
501 * Default callback for async RPC calls
504 rpc_default_callback(struct rpc_task *task, void *data)
508 static const struct rpc_call_ops rpc_default_ops = {
509 .rpc_call_done = rpc_default_callback,
513 * Export the signal mask handling for synchronous code that
514 * sleeps on RPC calls
516 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
518 static void rpc_save_sigmask(sigset_t *oldset, int intr)
520 unsigned long sigallow = sigmask(SIGKILL);
523 /* Block all signals except those listed in sigallow */
525 sigallow |= RPC_INTR_SIGNALS;
526 siginitsetinv(&sigmask, sigallow);
527 sigprocmask(SIG_BLOCK, &sigmask, oldset);
530 static void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
532 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
535 static void rpc_restore_sigmask(sigset_t *oldset)
537 sigprocmask(SIG_SETMASK, oldset, NULL);
540 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
542 rpc_save_sigmask(oldset, clnt->cl_intr);
544 EXPORT_SYMBOL_GPL(rpc_clnt_sigmask);
546 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
548 rpc_restore_sigmask(oldset);
550 EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask);
553 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
554 * @task_setup_data: pointer to task initialisation data
556 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
558 struct rpc_task *task, *ret;
561 task = rpc_new_task(task_setup_data);
563 rpc_release_calldata(task_setup_data->callback_ops,
564 task_setup_data->callback_data);
565 ret = ERR_PTR(-ENOMEM);
569 if (task->tk_status != 0) {
570 ret = ERR_PTR(task->tk_status);
574 atomic_inc(&task->tk_count);
575 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
576 rpc_task_sigmask(task, &oldset);
578 rpc_restore_sigmask(&oldset);
583 EXPORT_SYMBOL_GPL(rpc_run_task);
586 * rpc_call_sync - Perform a synchronous RPC call
587 * @clnt: pointer to RPC client
588 * @msg: RPC call parameters
589 * @flags: RPC call flags
591 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
593 struct rpc_task *task;
594 struct rpc_task_setup task_setup_data = {
597 .callback_ops = &rpc_default_ops,
602 BUG_ON(flags & RPC_TASK_ASYNC);
604 task = rpc_run_task(&task_setup_data);
606 return PTR_ERR(task);
607 status = task->tk_status;
611 EXPORT_SYMBOL_GPL(rpc_call_sync);
614 * rpc_call_async - Perform an asynchronous RPC call
615 * @clnt: pointer to RPC client
616 * @msg: RPC call parameters
617 * @flags: RPC call flags
619 * @data: user call data
622 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
623 const struct rpc_call_ops *tk_ops, void *data)
625 struct rpc_task *task;
626 struct rpc_task_setup task_setup_data = {
629 .callback_ops = tk_ops,
630 .callback_data = data,
631 .flags = flags|RPC_TASK_ASYNC,
634 task = rpc_run_task(&task_setup_data);
636 return PTR_ERR(task);
640 EXPORT_SYMBOL_GPL(rpc_call_async);
643 rpc_call_start(struct rpc_task *task)
645 task->tk_action = call_start;
647 EXPORT_SYMBOL_GPL(rpc_call_start);
650 * rpc_peeraddr - extract remote peer address from clnt's xprt
651 * @clnt: RPC client structure
652 * @buf: target buffer
653 * @size: length of target buffer
655 * Returns the number of bytes that are actually in the stored address.
657 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
660 struct rpc_xprt *xprt = clnt->cl_xprt;
662 bytes = sizeof(xprt->addr);
665 memcpy(buf, &clnt->cl_xprt->addr, bytes);
666 return xprt->addrlen;
668 EXPORT_SYMBOL_GPL(rpc_peeraddr);
671 * rpc_peeraddr2str - return remote peer address in printable format
672 * @clnt: RPC client structure
673 * @format: address format
676 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
678 struct rpc_xprt *xprt = clnt->cl_xprt;
680 if (xprt->address_strings[format] != NULL)
681 return xprt->address_strings[format];
683 return "unprintable";
685 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
688 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
690 struct rpc_xprt *xprt = clnt->cl_xprt;
691 if (xprt->ops->set_buffer_size)
692 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
694 EXPORT_SYMBOL_GPL(rpc_setbufsize);
697 * Return size of largest payload RPC client can support, in bytes
699 * For stream transports, this is one RPC record fragment (see RFC
700 * 1831), as we don't support multi-record requests yet. For datagram
701 * transports, this is the size of an IP packet minus the IP, UDP, and
704 size_t rpc_max_payload(struct rpc_clnt *clnt)
706 return clnt->cl_xprt->max_payload;
708 EXPORT_SYMBOL_GPL(rpc_max_payload);
711 * rpc_force_rebind - force transport to check that remote port is unchanged
712 * @clnt: client to rebind
715 void rpc_force_rebind(struct rpc_clnt *clnt)
717 if (clnt->cl_autobind)
718 xprt_clear_bound(clnt->cl_xprt);
720 EXPORT_SYMBOL_GPL(rpc_force_rebind);
723 * Restart an (async) RPC call. Usually called from within the
727 rpc_restart_call(struct rpc_task *task)
729 if (RPC_ASSASSINATED(task))
732 task->tk_action = call_start;
734 EXPORT_SYMBOL_GPL(rpc_restart_call);
739 * Other FSM states can be visited zero or more times, but
740 * this state is visited exactly once for each RPC.
743 call_start(struct rpc_task *task)
745 struct rpc_clnt *clnt = task->tk_client;
747 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
748 clnt->cl_protname, clnt->cl_vers,
749 task->tk_msg.rpc_proc->p_proc,
750 (RPC_IS_ASYNC(task) ? "async" : "sync"));
752 /* Increment call count */
753 task->tk_msg.rpc_proc->p_count++;
754 clnt->cl_stats->rpccnt++;
755 task->tk_action = call_reserve;
759 * 1. Reserve an RPC call slot
762 call_reserve(struct rpc_task *task)
766 if (!rpcauth_uptodatecred(task)) {
767 task->tk_action = call_refresh;
772 task->tk_action = call_reserveresult;
777 * 1b. Grok the result of xprt_reserve()
780 call_reserveresult(struct rpc_task *task)
782 int status = task->tk_status;
787 * After a call to xprt_reserve(), we must have either
788 * a request slot or else an error status.
792 if (task->tk_rqstp) {
793 task->tk_action = call_allocate;
797 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
798 __FUNCTION__, status);
799 rpc_exit(task, -EIO);
804 * Even though there was an error, we may have acquired
805 * a request slot somehow. Make sure not to leak it.
807 if (task->tk_rqstp) {
808 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
809 __FUNCTION__, status);
814 case -EAGAIN: /* woken up; retry */
815 task->tk_action = call_reserve;
817 case -EIO: /* probably a shutdown */
820 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
821 __FUNCTION__, status);
824 rpc_exit(task, status);
828 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
829 * (Note: buffer memory is freed in xprt_release).
832 call_allocate(struct rpc_task *task)
834 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
835 struct rpc_rqst *req = task->tk_rqstp;
836 struct rpc_xprt *xprt = task->tk_xprt;
837 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
842 task->tk_action = call_bind;
847 if (proc->p_proc != 0) {
848 BUG_ON(proc->p_arglen == 0);
849 if (proc->p_decode != NULL)
850 BUG_ON(proc->p_replen == 0);
854 * Calculate the size (in quads) of the RPC call
855 * and reply headers, and convert both values
858 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
859 req->rq_callsize <<= 2;
860 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
861 req->rq_rcvsize <<= 2;
863 req->rq_buffer = xprt->ops->buf_alloc(task,
864 req->rq_callsize + req->rq_rcvsize);
865 if (req->rq_buffer != NULL)
868 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
870 if (RPC_IS_ASYNC(task) || !signalled()) {
871 task->tk_action = call_allocate;
872 rpc_delay(task, HZ>>4);
876 rpc_exit(task, -ERESTARTSYS);
880 rpc_task_need_encode(struct rpc_task *task)
882 return task->tk_rqstp->rq_snd_buf.len == 0;
886 rpc_task_force_reencode(struct rpc_task *task)
888 task->tk_rqstp->rq_snd_buf.len = 0;
892 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
894 buf->head[0].iov_base = start;
895 buf->head[0].iov_len = len;
896 buf->tail[0].iov_len = 0;
904 * 3. Encode arguments of an RPC call
907 call_encode(struct rpc_task *task)
909 struct rpc_rqst *req = task->tk_rqstp;
915 rpc_xdr_buf_init(&req->rq_snd_buf,
918 rpc_xdr_buf_init(&req->rq_rcv_buf,
919 (char *)req->rq_buffer + req->rq_callsize,
922 /* Encode header and provided arguments */
923 encode = task->tk_msg.rpc_proc->p_encode;
924 if (!(p = call_header(task))) {
925 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
926 rpc_exit(task, -EIO);
932 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
933 task->tk_msg.rpc_argp);
934 if (task->tk_status == -ENOMEM) {
935 /* XXX: Is this sane? */
936 rpc_delay(task, 3*HZ);
937 task->tk_status = -EAGAIN;
942 * 4. Get the server port number if not yet set
945 call_bind(struct rpc_task *task)
947 struct rpc_xprt *xprt = task->tk_xprt;
951 task->tk_action = call_connect;
952 if (!xprt_bound(xprt)) {
953 task->tk_action = call_bind_status;
954 task->tk_timeout = xprt->bind_timeout;
955 xprt->ops->rpcbind(task);
960 * 4a. Sort out bind result
963 call_bind_status(struct rpc_task *task)
967 if (task->tk_status >= 0) {
970 task->tk_action = call_connect;
974 switch (task->tk_status) {
976 dprintk("RPC: %5u rpcbind waiting for another request "
977 "to finish\n", task->tk_pid);
978 /* avoid busy-waiting here -- could be a network outage. */
979 rpc_delay(task, 5*HZ);
982 dprintk("RPC: %5u remote rpcbind: RPC program/version "
983 "unavailable\n", task->tk_pid);
984 /* fail immediately if this is an RPC ping */
985 if (task->tk_msg.rpc_proc->p_proc == 0) {
986 status = -EOPNOTSUPP;
989 rpc_delay(task, 3*HZ);
992 dprintk("RPC: %5u rpcbind request timed out\n",
996 /* server doesn't support any rpcbind version we know of */
997 dprintk("RPC: %5u remote rpcbind service unavailable\n",
1000 case -EPROTONOSUPPORT:
1001 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1003 task->tk_status = 0;
1004 task->tk_action = call_bind;
1007 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1008 task->tk_pid, -task->tk_status);
1011 rpc_exit(task, status);
1015 task->tk_action = call_timeout;
1019 * 4b. Connect to the RPC server
1022 call_connect(struct rpc_task *task)
1024 struct rpc_xprt *xprt = task->tk_xprt;
1026 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1028 (xprt_connected(xprt) ? "is" : "is not"));
1030 task->tk_action = call_transmit;
1031 if (!xprt_connected(xprt)) {
1032 task->tk_action = call_connect_status;
1033 if (task->tk_status < 0)
1040 * 4c. Sort out connect result
1043 call_connect_status(struct rpc_task *task)
1045 struct rpc_clnt *clnt = task->tk_client;
1046 int status = task->tk_status;
1048 dprint_status(task);
1050 task->tk_status = 0;
1052 clnt->cl_stats->netreconn++;
1053 task->tk_action = call_transmit;
1057 /* Something failed: remote service port may have changed */
1058 rpc_force_rebind(clnt);
1063 task->tk_action = call_bind;
1064 if (!RPC_IS_SOFT(task))
1066 /* if soft mounted, test if we've timed out */
1068 task->tk_action = call_timeout;
1071 rpc_exit(task, -EIO);
1075 * 5. Transmit the RPC request, and wait for reply
1078 call_transmit(struct rpc_task *task)
1080 dprint_status(task);
1082 task->tk_action = call_status;
1083 if (task->tk_status < 0)
1085 task->tk_status = xprt_prepare_transmit(task);
1086 if (task->tk_status != 0)
1088 task->tk_action = call_transmit_status;
1089 /* Encode here so that rpcsec_gss can use correct sequence number. */
1090 if (rpc_task_need_encode(task)) {
1091 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1093 /* Did the encode result in an error condition? */
1094 if (task->tk_status != 0)
1097 xprt_transmit(task);
1098 if (task->tk_status < 0)
1101 * On success, ensure that we call xprt_end_transmit() before sleeping
1102 * in order to allow access to the socket to other RPC requests.
1104 call_transmit_status(task);
1105 if (task->tk_msg.rpc_proc->p_decode != NULL)
1107 task->tk_action = rpc_exit_task;
1108 rpc_wake_up_task(task);
1112 * 5a. Handle cleanup after a transmission
1115 call_transmit_status(struct rpc_task *task)
1117 task->tk_action = call_status;
1119 * Special case: if we've been waiting on the socket's write_space()
1120 * callback, then don't call xprt_end_transmit().
1122 if (task->tk_status == -EAGAIN)
1124 xprt_end_transmit(task);
1125 rpc_task_force_reencode(task);
1129 * 6. Sort out the RPC call status
1132 call_status(struct rpc_task *task)
1134 struct rpc_clnt *clnt = task->tk_client;
1135 struct rpc_rqst *req = task->tk_rqstp;
1138 if (req->rq_received > 0 && !req->rq_bytes_sent)
1139 task->tk_status = req->rq_received;
1141 dprint_status(task);
1143 status = task->tk_status;
1145 task->tk_action = call_decode;
1149 task->tk_status = 0;
1155 * Delay any retries for 3 seconds, then handle as if it
1158 rpc_delay(task, 3*HZ);
1160 task->tk_action = call_timeout;
1161 if (task->tk_client->cl_discrtry)
1162 xprt_force_disconnect(task->tk_xprt);
1166 rpc_force_rebind(clnt);
1167 task->tk_action = call_bind;
1170 task->tk_action = call_transmit;
1173 /* shutdown or soft timeout */
1174 rpc_exit(task, status);
1177 printk("%s: RPC call returned error %d\n",
1178 clnt->cl_protname, -status);
1179 rpc_exit(task, status);
1184 * 6a. Handle RPC timeout
1185 * We do not release the request slot, so we keep using the
1186 * same XID for all retransmits.
1189 call_timeout(struct rpc_task *task)
1191 struct rpc_clnt *clnt = task->tk_client;
1193 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1194 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1198 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1199 task->tk_timeouts++;
1201 if (RPC_IS_SOFT(task)) {
1202 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1203 clnt->cl_protname, clnt->cl_server);
1204 rpc_exit(task, -EIO);
1208 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1209 task->tk_flags |= RPC_CALL_MAJORSEEN;
1210 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1211 clnt->cl_protname, clnt->cl_server);
1213 rpc_force_rebind(clnt);
1216 clnt->cl_stats->rpcretrans++;
1217 task->tk_action = call_bind;
1218 task->tk_status = 0;
1222 * 7. Decode the RPC reply
1225 call_decode(struct rpc_task *task)
1227 struct rpc_clnt *clnt = task->tk_client;
1228 struct rpc_rqst *req = task->tk_rqstp;
1229 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1232 dprintk("RPC: %5u call_decode (status %d)\n",
1233 task->tk_pid, task->tk_status);
1235 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1236 printk(KERN_NOTICE "%s: server %s OK\n",
1237 clnt->cl_protname, clnt->cl_server);
1238 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1241 if (task->tk_status < 12) {
1242 if (!RPC_IS_SOFT(task)) {
1243 task->tk_action = call_bind;
1244 clnt->cl_stats->rpcretrans++;
1247 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1248 clnt->cl_protname, task->tk_status);
1249 task->tk_action = call_timeout;
1254 * Ensure that we see all writes made by xprt_complete_rqst()
1255 * before it changed req->rq_received.
1258 req->rq_rcv_buf.len = req->rq_private_buf.len;
1260 /* Check that the softirq receive buffer is valid */
1261 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1262 sizeof(req->rq_rcv_buf)) != 0);
1264 /* Verify the RPC header */
1265 p = call_verify(task);
1267 if (p == ERR_PTR(-EAGAIN))
1272 task->tk_action = rpc_exit_task;
1275 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1276 task->tk_msg.rpc_resp);
1278 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1282 req->rq_received = req->rq_private_buf.len = 0;
1283 task->tk_status = 0;
1284 if (task->tk_client->cl_discrtry)
1285 xprt_force_disconnect(task->tk_xprt);
1289 * 8. Refresh the credentials if rejected by the server
1292 call_refresh(struct rpc_task *task)
1294 dprint_status(task);
1296 task->tk_action = call_refreshresult;
1297 task->tk_status = 0;
1298 task->tk_client->cl_stats->rpcauthrefresh++;
1299 rpcauth_refreshcred(task);
1303 * 8a. Process the results of a credential refresh
1306 call_refreshresult(struct rpc_task *task)
1308 int status = task->tk_status;
1310 dprint_status(task);
1312 task->tk_status = 0;
1313 task->tk_action = call_reserve;
1314 if (status >= 0 && rpcauth_uptodatecred(task))
1316 if (status == -EACCES) {
1317 rpc_exit(task, -EACCES);
1320 task->tk_action = call_refresh;
1321 if (status != -ETIMEDOUT)
1322 rpc_delay(task, 3*HZ);
1327 * Call header serialization
1330 call_header(struct rpc_task *task)
1332 struct rpc_clnt *clnt = task->tk_client;
1333 struct rpc_rqst *req = task->tk_rqstp;
1334 __be32 *p = req->rq_svec[0].iov_base;
1336 /* FIXME: check buffer size? */
1338 p = xprt_skip_transport_header(task->tk_xprt, p);
1339 *p++ = req->rq_xid; /* XID */
1340 *p++ = htonl(RPC_CALL); /* CALL */
1341 *p++ = htonl(RPC_VERSION); /* RPC version */
1342 *p++ = htonl(clnt->cl_prog); /* program number */
1343 *p++ = htonl(clnt->cl_vers); /* program version */
1344 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1345 p = rpcauth_marshcred(task, p);
1346 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1351 * Reply header verification
1354 call_verify(struct rpc_task *task)
1356 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1357 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1358 __be32 *p = iov->iov_base;
1360 int error = -EACCES;
1362 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1363 /* RFC-1014 says that the representation of XDR data must be a
1364 * multiple of four bytes
1365 * - if it isn't pointer subtraction in the NFS client may give
1368 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1369 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1370 task->tk_rqstp->rq_rcv_buf.len);
1375 p += 1; /* skip XID */
1377 if ((n = ntohl(*p++)) != RPC_REPLY) {
1378 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1379 task->tk_pid, __FUNCTION__, n);
1382 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1385 switch ((n = ntohl(*p++))) {
1386 case RPC_AUTH_ERROR:
1389 dprintk("RPC: %5u %s: RPC call version "
1391 task->tk_pid, __FUNCTION__);
1392 error = -EPROTONOSUPPORT;
1395 dprintk("RPC: %5u %s: RPC call rejected, "
1396 "unknown error: %x\n",
1397 task->tk_pid, __FUNCTION__, n);
1402 switch ((n = ntohl(*p++))) {
1403 case RPC_AUTH_REJECTEDCRED:
1404 case RPC_AUTH_REJECTEDVERF:
1405 case RPCSEC_GSS_CREDPROBLEM:
1406 case RPCSEC_GSS_CTXPROBLEM:
1407 if (!task->tk_cred_retry)
1409 task->tk_cred_retry--;
1410 dprintk("RPC: %5u %s: retry stale creds\n",
1411 task->tk_pid, __FUNCTION__);
1412 rpcauth_invalcred(task);
1413 /* Ensure we obtain a new XID! */
1415 task->tk_action = call_refresh;
1417 case RPC_AUTH_BADCRED:
1418 case RPC_AUTH_BADVERF:
1419 /* possibly garbled cred/verf? */
1420 if (!task->tk_garb_retry)
1422 task->tk_garb_retry--;
1423 dprintk("RPC: %5u %s: retry garbled creds\n",
1424 task->tk_pid, __FUNCTION__);
1425 task->tk_action = call_bind;
1427 case RPC_AUTH_TOOWEAK:
1428 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1429 "authentication.\n", task->tk_client->cl_server);
1432 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1433 task->tk_pid, __FUNCTION__, n);
1436 dprintk("RPC: %5u %s: call rejected %d\n",
1437 task->tk_pid, __FUNCTION__, n);
1440 if (!(p = rpcauth_checkverf(task, p))) {
1441 dprintk("RPC: %5u %s: auth check failed\n",
1442 task->tk_pid, __FUNCTION__);
1443 goto out_garbage; /* bad verifier, retry */
1445 len = p - (__be32 *)iov->iov_base - 1;
1448 switch ((n = ntohl(*p++))) {
1451 case RPC_PROG_UNAVAIL:
1452 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1453 task->tk_pid, __FUNCTION__,
1454 (unsigned int)task->tk_client->cl_prog,
1455 task->tk_client->cl_server);
1456 error = -EPFNOSUPPORT;
1458 case RPC_PROG_MISMATCH:
1459 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1460 "server %s\n", task->tk_pid, __FUNCTION__,
1461 (unsigned int)task->tk_client->cl_prog,
1462 (unsigned int)task->tk_client->cl_vers,
1463 task->tk_client->cl_server);
1464 error = -EPROTONOSUPPORT;
1466 case RPC_PROC_UNAVAIL:
1467 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1468 "version %u on server %s\n",
1469 task->tk_pid, __FUNCTION__,
1470 task->tk_msg.rpc_proc,
1471 task->tk_client->cl_prog,
1472 task->tk_client->cl_vers,
1473 task->tk_client->cl_server);
1474 error = -EOPNOTSUPP;
1476 case RPC_GARBAGE_ARGS:
1477 dprintk("RPC: %5u %s: server saw garbage\n",
1478 task->tk_pid, __FUNCTION__);
1481 dprintk("RPC: %5u %s: server accept status: %x\n",
1482 task->tk_pid, __FUNCTION__, n);
1487 task->tk_client->cl_stats->rpcgarbage++;
1488 if (task->tk_garb_retry) {
1489 task->tk_garb_retry--;
1490 dprintk("RPC: %5u %s: retrying\n",
1491 task->tk_pid, __FUNCTION__);
1492 task->tk_action = call_bind;
1494 return ERR_PTR(-EAGAIN);
1499 rpc_exit(task, error);
1500 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1501 __FUNCTION__, error);
1502 return ERR_PTR(error);
1504 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1509 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1514 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1519 static struct rpc_procinfo rpcproc_null = {
1520 .p_encode = rpcproc_encode_null,
1521 .p_decode = rpcproc_decode_null,
1524 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1526 struct rpc_message msg = {
1527 .rpc_proc = &rpcproc_null,
1530 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1531 err = rpc_call_sync(clnt, &msg, flags);
1532 put_rpccred(msg.rpc_cred);
1536 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1538 struct rpc_message msg = {
1539 .rpc_proc = &rpcproc_null,
1542 struct rpc_task_setup task_setup_data = {
1544 .rpc_message = &msg,
1545 .callback_ops = &rpc_default_ops,
1548 return rpc_run_task(&task_setup_data);
1550 EXPORT_SYMBOL_GPL(rpc_call_null);
1553 void rpc_show_tasks(void)
1555 struct rpc_clnt *clnt;
1558 spin_lock(&rpc_client_lock);
1559 if (list_empty(&all_clients))
1561 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1562 "-rpcwait -action- ---ops--\n");
1563 list_for_each_entry(clnt, &all_clients, cl_clients) {
1564 if (list_empty(&clnt->cl_tasks))
1566 spin_lock(&clnt->cl_lock);
1567 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1568 const char *rpc_waitq = "none";
1571 if (t->tk_msg.rpc_proc)
1572 proc = t->tk_msg.rpc_proc->p_proc;
1576 if (RPC_IS_QUEUED(t))
1577 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1579 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1581 t->tk_flags, t->tk_status,
1583 (t->tk_client ? t->tk_client->cl_prog : 0),
1584 t->tk_rqstp, t->tk_timeout,
1586 t->tk_action, t->tk_ops);
1588 spin_unlock(&clnt->cl_lock);
1591 spin_unlock(&rpc_client_lock);