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_timeout = xprt->timeout;
192 if (args->timeout != NULL) {
193 memcpy(&clnt->cl_timeout_default, args->timeout,
194 sizeof(clnt->cl_timeout_default));
195 clnt->cl_timeout = &clnt->cl_timeout_default;
198 clnt->cl_rtt = &clnt->cl_rtt_default;
199 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
201 kref_init(&clnt->cl_kref);
203 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
207 auth = rpcauth_create(args->authflavor, clnt);
209 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
215 /* save the nodename */
216 clnt->cl_nodelen = strlen(utsname()->nodename);
217 if (clnt->cl_nodelen > UNX_MAXNODENAME)
218 clnt->cl_nodelen = UNX_MAXNODENAME;
219 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
220 rpc_register_client(clnt);
224 if (!IS_ERR(clnt->cl_dentry)) {
225 rpc_rmdir(clnt->cl_dentry);
229 rpc_free_iostats(clnt->cl_metrics);
231 if (clnt->cl_server != clnt->cl_inline_name)
232 kfree(clnt->cl_server);
243 * rpc_create - create an RPC client and transport with one call
244 * @args: rpc_clnt create argument structure
246 * Creates and initializes an RPC transport and an RPC client.
248 * It can ping the server in order to determine if it is up, and to see if
249 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
250 * this behavior so asynchronous tasks can also use rpc_create.
252 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
254 struct rpc_xprt *xprt;
255 struct rpc_clnt *clnt;
256 struct xprt_create xprtargs = {
257 .ident = args->protocol,
258 .srcaddr = args->saddress,
259 .dstaddr = args->address,
260 .addrlen = args->addrsize,
264 xprt = xprt_create_transport(&xprtargs);
266 return (struct rpc_clnt *)xprt;
269 * If the caller chooses not to specify a hostname, whip
270 * up a string representation of the passed-in address.
272 if (args->servername == NULL) {
273 servername[0] = '\0';
274 switch (args->address->sa_family) {
276 struct sockaddr_in *sin =
277 (struct sockaddr_in *)args->address;
278 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
279 NIPQUAD(sin->sin_addr.s_addr));
283 struct sockaddr_in6 *sin =
284 (struct sockaddr_in6 *)args->address;
285 snprintf(servername, sizeof(servername), NIP6_FMT,
286 NIP6(sin->sin6_addr));
290 /* caller wants default server name, but
291 * address family isn't recognized. */
292 return ERR_PTR(-EINVAL);
294 args->servername = servername;
297 xprt = xprt_create_transport(&xprtargs);
299 return (struct rpc_clnt *)xprt;
302 * By default, kernel RPC client connects from a reserved port.
303 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
304 * but it is always enabled for rpciod, which handles the connect
308 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
311 clnt = rpc_new_client(args, xprt);
315 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
316 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
318 rpc_shutdown_client(clnt);
323 clnt->cl_softrtry = 1;
324 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
325 clnt->cl_softrtry = 0;
327 if (args->flags & RPC_CLNT_CREATE_INTR)
329 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
330 clnt->cl_autobind = 1;
331 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
332 clnt->cl_discrtry = 1;
336 EXPORT_SYMBOL_GPL(rpc_create);
339 * This function clones the RPC client structure. It allows us to share the
340 * same transport while varying parameters such as the authentication
344 rpc_clone_client(struct rpc_clnt *clnt)
346 struct rpc_clnt *new;
349 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
352 new->cl_parent = clnt;
353 /* Turn off autobind on clones */
354 new->cl_autobind = 0;
355 INIT_LIST_HEAD(&new->cl_tasks);
356 spin_lock_init(&new->cl_lock);
357 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
358 new->cl_metrics = rpc_alloc_iostats(clnt);
359 if (new->cl_metrics == NULL)
361 kref_init(&new->cl_kref);
362 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
366 atomic_inc(&new->cl_auth->au_count);
367 xprt_get(clnt->cl_xprt);
368 kref_get(&clnt->cl_kref);
369 rpc_register_client(new);
373 rpc_free_iostats(new->cl_metrics);
377 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
380 EXPORT_SYMBOL_GPL(rpc_clone_client);
383 * Properly shut down an RPC client, terminating all outstanding
386 void rpc_shutdown_client(struct rpc_clnt *clnt)
388 dprintk("RPC: shutting down %s client for %s\n",
389 clnt->cl_protname, clnt->cl_server);
391 while (!list_empty(&clnt->cl_tasks)) {
392 rpc_killall_tasks(clnt);
393 wait_event_timeout(destroy_wait,
394 list_empty(&clnt->cl_tasks), 1*HZ);
397 rpc_release_client(clnt);
399 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
405 rpc_free_client(struct kref *kref)
407 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
409 dprintk("RPC: destroying %s client for %s\n",
410 clnt->cl_protname, clnt->cl_server);
411 if (!IS_ERR(clnt->cl_dentry)) {
412 rpc_rmdir(clnt->cl_dentry);
415 if (clnt->cl_parent != clnt) {
416 rpc_release_client(clnt->cl_parent);
419 if (clnt->cl_server != clnt->cl_inline_name)
420 kfree(clnt->cl_server);
422 rpc_unregister_client(clnt);
423 rpc_free_iostats(clnt->cl_metrics);
424 clnt->cl_metrics = NULL;
425 xprt_put(clnt->cl_xprt);
434 rpc_free_auth(struct kref *kref)
436 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
438 if (clnt->cl_auth == NULL) {
439 rpc_free_client(kref);
444 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
445 * release remaining GSS contexts. This mechanism ensures
446 * that it can do so safely.
449 rpcauth_release(clnt->cl_auth);
450 clnt->cl_auth = NULL;
451 kref_put(kref, rpc_free_client);
455 * Release reference to the RPC client
458 rpc_release_client(struct rpc_clnt *clnt)
460 dprintk("RPC: rpc_release_client(%p)\n", clnt);
462 if (list_empty(&clnt->cl_tasks))
463 wake_up(&destroy_wait);
464 kref_put(&clnt->cl_kref, rpc_free_auth);
468 * rpc_bind_new_program - bind a new RPC program to an existing client
469 * @old - old rpc_client
470 * @program - rpc program to set
471 * @vers - rpc program version
473 * Clones the rpc client and sets up a new RPC program. This is mainly
474 * of use for enabling different RPC programs to share the same transport.
475 * The Sun NFSv2/v3 ACL protocol can do this.
477 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
478 struct rpc_program *program,
481 struct rpc_clnt *clnt;
482 struct rpc_version *version;
485 BUG_ON(vers >= program->nrvers || !program->version[vers]);
486 version = program->version[vers];
487 clnt = rpc_clone_client(old);
490 clnt->cl_procinfo = version->procs;
491 clnt->cl_maxproc = version->nrprocs;
492 clnt->cl_protname = program->name;
493 clnt->cl_prog = program->number;
494 clnt->cl_vers = version->number;
495 clnt->cl_stats = program->stats;
496 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
498 rpc_shutdown_client(clnt);
504 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
507 * Default callback for async RPC calls
510 rpc_default_callback(struct rpc_task *task, void *data)
514 static const struct rpc_call_ops rpc_default_ops = {
515 .rpc_call_done = rpc_default_callback,
519 * Export the signal mask handling for synchronous code that
520 * sleeps on RPC calls
522 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
524 static void rpc_save_sigmask(sigset_t *oldset, int intr)
526 unsigned long sigallow = sigmask(SIGKILL);
529 /* Block all signals except those listed in sigallow */
531 sigallow |= RPC_INTR_SIGNALS;
532 siginitsetinv(&sigmask, sigallow);
533 sigprocmask(SIG_BLOCK, &sigmask, oldset);
536 static void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
538 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
541 static void rpc_restore_sigmask(sigset_t *oldset)
543 sigprocmask(SIG_SETMASK, oldset, NULL);
546 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
548 rpc_save_sigmask(oldset, clnt->cl_intr);
550 EXPORT_SYMBOL_GPL(rpc_clnt_sigmask);
552 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
554 rpc_restore_sigmask(oldset);
556 EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask);
559 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
560 * @task_setup_data: pointer to task initialisation data
562 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
564 struct rpc_task *task, *ret;
567 task = rpc_new_task(task_setup_data);
569 rpc_release_calldata(task_setup_data->callback_ops,
570 task_setup_data->callback_data);
571 ret = ERR_PTR(-ENOMEM);
575 if (task->tk_status != 0) {
576 ret = ERR_PTR(task->tk_status);
580 atomic_inc(&task->tk_count);
581 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
582 rpc_task_sigmask(task, &oldset);
584 rpc_restore_sigmask(&oldset);
589 EXPORT_SYMBOL_GPL(rpc_run_task);
592 * rpc_call_sync - Perform a synchronous RPC call
593 * @clnt: pointer to RPC client
594 * @msg: RPC call parameters
595 * @flags: RPC call flags
597 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
599 struct rpc_task *task;
600 struct rpc_task_setup task_setup_data = {
603 .callback_ops = &rpc_default_ops,
608 BUG_ON(flags & RPC_TASK_ASYNC);
610 task = rpc_run_task(&task_setup_data);
612 return PTR_ERR(task);
613 status = task->tk_status;
617 EXPORT_SYMBOL_GPL(rpc_call_sync);
620 * rpc_call_async - Perform an asynchronous RPC call
621 * @clnt: pointer to RPC client
622 * @msg: RPC call parameters
623 * @flags: RPC call flags
625 * @data: user call data
628 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
629 const struct rpc_call_ops *tk_ops, void *data)
631 struct rpc_task *task;
632 struct rpc_task_setup task_setup_data = {
635 .callback_ops = tk_ops,
636 .callback_data = data,
637 .flags = flags|RPC_TASK_ASYNC,
640 task = rpc_run_task(&task_setup_data);
642 return PTR_ERR(task);
646 EXPORT_SYMBOL_GPL(rpc_call_async);
649 rpc_call_start(struct rpc_task *task)
651 task->tk_action = call_start;
653 EXPORT_SYMBOL_GPL(rpc_call_start);
656 * rpc_peeraddr - extract remote peer address from clnt's xprt
657 * @clnt: RPC client structure
658 * @buf: target buffer
659 * @size: length of target buffer
661 * Returns the number of bytes that are actually in the stored address.
663 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
666 struct rpc_xprt *xprt = clnt->cl_xprt;
668 bytes = sizeof(xprt->addr);
671 memcpy(buf, &clnt->cl_xprt->addr, bytes);
672 return xprt->addrlen;
674 EXPORT_SYMBOL_GPL(rpc_peeraddr);
677 * rpc_peeraddr2str - return remote peer address in printable format
678 * @clnt: RPC client structure
679 * @format: address format
682 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
683 enum rpc_display_format_t format)
685 struct rpc_xprt *xprt = clnt->cl_xprt;
687 if (xprt->address_strings[format] != NULL)
688 return xprt->address_strings[format];
690 return "unprintable";
692 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
695 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
697 struct rpc_xprt *xprt = clnt->cl_xprt;
698 if (xprt->ops->set_buffer_size)
699 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
701 EXPORT_SYMBOL_GPL(rpc_setbufsize);
704 * Return size of largest payload RPC client can support, in bytes
706 * For stream transports, this is one RPC record fragment (see RFC
707 * 1831), as we don't support multi-record requests yet. For datagram
708 * transports, this is the size of an IP packet minus the IP, UDP, and
711 size_t rpc_max_payload(struct rpc_clnt *clnt)
713 return clnt->cl_xprt->max_payload;
715 EXPORT_SYMBOL_GPL(rpc_max_payload);
718 * rpc_force_rebind - force transport to check that remote port is unchanged
719 * @clnt: client to rebind
722 void rpc_force_rebind(struct rpc_clnt *clnt)
724 if (clnt->cl_autobind)
725 xprt_clear_bound(clnt->cl_xprt);
727 EXPORT_SYMBOL_GPL(rpc_force_rebind);
730 * Restart an (async) RPC call. Usually called from within the
734 rpc_restart_call(struct rpc_task *task)
736 if (RPC_ASSASSINATED(task))
739 task->tk_action = call_start;
741 EXPORT_SYMBOL_GPL(rpc_restart_call);
746 * Other FSM states can be visited zero or more times, but
747 * this state is visited exactly once for each RPC.
750 call_start(struct rpc_task *task)
752 struct rpc_clnt *clnt = task->tk_client;
754 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
755 clnt->cl_protname, clnt->cl_vers,
756 task->tk_msg.rpc_proc->p_proc,
757 (RPC_IS_ASYNC(task) ? "async" : "sync"));
759 /* Increment call count */
760 task->tk_msg.rpc_proc->p_count++;
761 clnt->cl_stats->rpccnt++;
762 task->tk_action = call_reserve;
766 * 1. Reserve an RPC call slot
769 call_reserve(struct rpc_task *task)
773 if (!rpcauth_uptodatecred(task)) {
774 task->tk_action = call_refresh;
779 task->tk_action = call_reserveresult;
784 * 1b. Grok the result of xprt_reserve()
787 call_reserveresult(struct rpc_task *task)
789 int status = task->tk_status;
794 * After a call to xprt_reserve(), we must have either
795 * a request slot or else an error status.
799 if (task->tk_rqstp) {
800 task->tk_action = call_allocate;
804 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
805 __FUNCTION__, status);
806 rpc_exit(task, -EIO);
811 * Even though there was an error, we may have acquired
812 * a request slot somehow. Make sure not to leak it.
814 if (task->tk_rqstp) {
815 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
816 __FUNCTION__, status);
821 case -EAGAIN: /* woken up; retry */
822 task->tk_action = call_reserve;
824 case -EIO: /* probably a shutdown */
827 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
828 __FUNCTION__, status);
831 rpc_exit(task, status);
835 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
836 * (Note: buffer memory is freed in xprt_release).
839 call_allocate(struct rpc_task *task)
841 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
842 struct rpc_rqst *req = task->tk_rqstp;
843 struct rpc_xprt *xprt = task->tk_xprt;
844 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
849 task->tk_action = call_bind;
854 if (proc->p_proc != 0) {
855 BUG_ON(proc->p_arglen == 0);
856 if (proc->p_decode != NULL)
857 BUG_ON(proc->p_replen == 0);
861 * Calculate the size (in quads) of the RPC call
862 * and reply headers, and convert both values
865 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
866 req->rq_callsize <<= 2;
867 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
868 req->rq_rcvsize <<= 2;
870 req->rq_buffer = xprt->ops->buf_alloc(task,
871 req->rq_callsize + req->rq_rcvsize);
872 if (req->rq_buffer != NULL)
875 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
877 if (RPC_IS_ASYNC(task) || !signalled()) {
878 task->tk_action = call_allocate;
879 rpc_delay(task, HZ>>4);
883 rpc_exit(task, -ERESTARTSYS);
887 rpc_task_need_encode(struct rpc_task *task)
889 return task->tk_rqstp->rq_snd_buf.len == 0;
893 rpc_task_force_reencode(struct rpc_task *task)
895 task->tk_rqstp->rq_snd_buf.len = 0;
899 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
901 buf->head[0].iov_base = start;
902 buf->head[0].iov_len = len;
903 buf->tail[0].iov_len = 0;
911 * 3. Encode arguments of an RPC call
914 call_encode(struct rpc_task *task)
916 struct rpc_rqst *req = task->tk_rqstp;
922 rpc_xdr_buf_init(&req->rq_snd_buf,
925 rpc_xdr_buf_init(&req->rq_rcv_buf,
926 (char *)req->rq_buffer + req->rq_callsize,
929 /* Encode header and provided arguments */
930 encode = task->tk_msg.rpc_proc->p_encode;
931 if (!(p = call_header(task))) {
932 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
933 rpc_exit(task, -EIO);
939 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
940 task->tk_msg.rpc_argp);
941 if (task->tk_status == -ENOMEM) {
942 /* XXX: Is this sane? */
943 rpc_delay(task, 3*HZ);
944 task->tk_status = -EAGAIN;
949 * 4. Get the server port number if not yet set
952 call_bind(struct rpc_task *task)
954 struct rpc_xprt *xprt = task->tk_xprt;
958 task->tk_action = call_connect;
959 if (!xprt_bound(xprt)) {
960 task->tk_action = call_bind_status;
961 task->tk_timeout = xprt->bind_timeout;
962 xprt->ops->rpcbind(task);
967 * 4a. Sort out bind result
970 call_bind_status(struct rpc_task *task)
974 if (task->tk_status >= 0) {
977 task->tk_action = call_connect;
981 switch (task->tk_status) {
983 dprintk("RPC: %5u rpcbind waiting for another request "
984 "to finish\n", task->tk_pid);
985 /* avoid busy-waiting here -- could be a network outage. */
986 rpc_delay(task, 5*HZ);
989 dprintk("RPC: %5u remote rpcbind: RPC program/version "
990 "unavailable\n", task->tk_pid);
991 /* fail immediately if this is an RPC ping */
992 if (task->tk_msg.rpc_proc->p_proc == 0) {
993 status = -EOPNOTSUPP;
996 rpc_delay(task, 3*HZ);
999 dprintk("RPC: %5u rpcbind request timed out\n",
1003 /* server doesn't support any rpcbind version we know of */
1004 dprintk("RPC: %5u remote rpcbind service unavailable\n",
1007 case -EPROTONOSUPPORT:
1008 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1010 task->tk_status = 0;
1011 task->tk_action = call_bind;
1014 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1015 task->tk_pid, -task->tk_status);
1018 rpc_exit(task, status);
1022 task->tk_action = call_timeout;
1026 * 4b. Connect to the RPC server
1029 call_connect(struct rpc_task *task)
1031 struct rpc_xprt *xprt = task->tk_xprt;
1033 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1035 (xprt_connected(xprt) ? "is" : "is not"));
1037 task->tk_action = call_transmit;
1038 if (!xprt_connected(xprt)) {
1039 task->tk_action = call_connect_status;
1040 if (task->tk_status < 0)
1047 * 4c. Sort out connect result
1050 call_connect_status(struct rpc_task *task)
1052 struct rpc_clnt *clnt = task->tk_client;
1053 int status = task->tk_status;
1055 dprint_status(task);
1057 task->tk_status = 0;
1059 clnt->cl_stats->netreconn++;
1060 task->tk_action = call_transmit;
1064 /* Something failed: remote service port may have changed */
1065 rpc_force_rebind(clnt);
1070 task->tk_action = call_bind;
1071 if (!RPC_IS_SOFT(task))
1073 /* if soft mounted, test if we've timed out */
1075 task->tk_action = call_timeout;
1078 rpc_exit(task, -EIO);
1082 * 5. Transmit the RPC request, and wait for reply
1085 call_transmit(struct rpc_task *task)
1087 dprint_status(task);
1089 task->tk_action = call_status;
1090 if (task->tk_status < 0)
1092 task->tk_status = xprt_prepare_transmit(task);
1093 if (task->tk_status != 0)
1095 task->tk_action = call_transmit_status;
1096 /* Encode here so that rpcsec_gss can use correct sequence number. */
1097 if (rpc_task_need_encode(task)) {
1098 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1100 /* Did the encode result in an error condition? */
1101 if (task->tk_status != 0)
1104 xprt_transmit(task);
1105 if (task->tk_status < 0)
1108 * On success, ensure that we call xprt_end_transmit() before sleeping
1109 * in order to allow access to the socket to other RPC requests.
1111 call_transmit_status(task);
1112 if (task->tk_msg.rpc_proc->p_decode != NULL)
1114 task->tk_action = rpc_exit_task;
1115 rpc_wake_up_task(task);
1119 * 5a. Handle cleanup after a transmission
1122 call_transmit_status(struct rpc_task *task)
1124 task->tk_action = call_status;
1126 * Special case: if we've been waiting on the socket's write_space()
1127 * callback, then don't call xprt_end_transmit().
1129 if (task->tk_status == -EAGAIN)
1131 xprt_end_transmit(task);
1132 rpc_task_force_reencode(task);
1136 * 6. Sort out the RPC call status
1139 call_status(struct rpc_task *task)
1141 struct rpc_clnt *clnt = task->tk_client;
1142 struct rpc_rqst *req = task->tk_rqstp;
1145 if (req->rq_received > 0 && !req->rq_bytes_sent)
1146 task->tk_status = req->rq_received;
1148 dprint_status(task);
1150 status = task->tk_status;
1152 task->tk_action = call_decode;
1156 task->tk_status = 0;
1162 * Delay any retries for 3 seconds, then handle as if it
1165 rpc_delay(task, 3*HZ);
1167 task->tk_action = call_timeout;
1168 if (task->tk_client->cl_discrtry)
1169 xprt_force_disconnect(task->tk_xprt);
1173 rpc_force_rebind(clnt);
1174 task->tk_action = call_bind;
1177 task->tk_action = call_transmit;
1180 /* shutdown or soft timeout */
1181 rpc_exit(task, status);
1184 printk("%s: RPC call returned error %d\n",
1185 clnt->cl_protname, -status);
1186 rpc_exit(task, status);
1191 * 6a. Handle RPC timeout
1192 * We do not release the request slot, so we keep using the
1193 * same XID for all retransmits.
1196 call_timeout(struct rpc_task *task)
1198 struct rpc_clnt *clnt = task->tk_client;
1200 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1201 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1205 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1206 task->tk_timeouts++;
1208 if (RPC_IS_SOFT(task)) {
1209 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1210 clnt->cl_protname, clnt->cl_server);
1211 rpc_exit(task, -EIO);
1215 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1216 task->tk_flags |= RPC_CALL_MAJORSEEN;
1217 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1218 clnt->cl_protname, clnt->cl_server);
1220 rpc_force_rebind(clnt);
1223 clnt->cl_stats->rpcretrans++;
1224 task->tk_action = call_bind;
1225 task->tk_status = 0;
1229 * 7. Decode the RPC reply
1232 call_decode(struct rpc_task *task)
1234 struct rpc_clnt *clnt = task->tk_client;
1235 struct rpc_rqst *req = task->tk_rqstp;
1236 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1239 dprintk("RPC: %5u call_decode (status %d)\n",
1240 task->tk_pid, task->tk_status);
1242 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1243 printk(KERN_NOTICE "%s: server %s OK\n",
1244 clnt->cl_protname, clnt->cl_server);
1245 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1248 if (task->tk_status < 12) {
1249 if (!RPC_IS_SOFT(task)) {
1250 task->tk_action = call_bind;
1251 clnt->cl_stats->rpcretrans++;
1254 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1255 clnt->cl_protname, task->tk_status);
1256 task->tk_action = call_timeout;
1261 * Ensure that we see all writes made by xprt_complete_rqst()
1262 * before it changed req->rq_received.
1265 req->rq_rcv_buf.len = req->rq_private_buf.len;
1267 /* Check that the softirq receive buffer is valid */
1268 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1269 sizeof(req->rq_rcv_buf)) != 0);
1271 /* Verify the RPC header */
1272 p = call_verify(task);
1274 if (p == ERR_PTR(-EAGAIN))
1279 task->tk_action = rpc_exit_task;
1282 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1283 task->tk_msg.rpc_resp);
1285 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1289 req->rq_received = req->rq_private_buf.len = 0;
1290 task->tk_status = 0;
1291 if (task->tk_client->cl_discrtry)
1292 xprt_force_disconnect(task->tk_xprt);
1296 * 8. Refresh the credentials if rejected by the server
1299 call_refresh(struct rpc_task *task)
1301 dprint_status(task);
1303 task->tk_action = call_refreshresult;
1304 task->tk_status = 0;
1305 task->tk_client->cl_stats->rpcauthrefresh++;
1306 rpcauth_refreshcred(task);
1310 * 8a. Process the results of a credential refresh
1313 call_refreshresult(struct rpc_task *task)
1315 int status = task->tk_status;
1317 dprint_status(task);
1319 task->tk_status = 0;
1320 task->tk_action = call_reserve;
1321 if (status >= 0 && rpcauth_uptodatecred(task))
1323 if (status == -EACCES) {
1324 rpc_exit(task, -EACCES);
1327 task->tk_action = call_refresh;
1328 if (status != -ETIMEDOUT)
1329 rpc_delay(task, 3*HZ);
1334 * Call header serialization
1337 call_header(struct rpc_task *task)
1339 struct rpc_clnt *clnt = task->tk_client;
1340 struct rpc_rqst *req = task->tk_rqstp;
1341 __be32 *p = req->rq_svec[0].iov_base;
1343 /* FIXME: check buffer size? */
1345 p = xprt_skip_transport_header(task->tk_xprt, p);
1346 *p++ = req->rq_xid; /* XID */
1347 *p++ = htonl(RPC_CALL); /* CALL */
1348 *p++ = htonl(RPC_VERSION); /* RPC version */
1349 *p++ = htonl(clnt->cl_prog); /* program number */
1350 *p++ = htonl(clnt->cl_vers); /* program version */
1351 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1352 p = rpcauth_marshcred(task, p);
1353 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1358 * Reply header verification
1361 call_verify(struct rpc_task *task)
1363 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1364 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1365 __be32 *p = iov->iov_base;
1367 int error = -EACCES;
1369 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1370 /* RFC-1014 says that the representation of XDR data must be a
1371 * multiple of four bytes
1372 * - if it isn't pointer subtraction in the NFS client may give
1375 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1376 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1377 task->tk_rqstp->rq_rcv_buf.len);
1382 p += 1; /* skip XID */
1384 if ((n = ntohl(*p++)) != RPC_REPLY) {
1385 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1386 task->tk_pid, __FUNCTION__, n);
1389 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1392 switch ((n = ntohl(*p++))) {
1393 case RPC_AUTH_ERROR:
1396 dprintk("RPC: %5u %s: RPC call version "
1398 task->tk_pid, __FUNCTION__);
1399 error = -EPROTONOSUPPORT;
1402 dprintk("RPC: %5u %s: RPC call rejected, "
1403 "unknown error: %x\n",
1404 task->tk_pid, __FUNCTION__, n);
1409 switch ((n = ntohl(*p++))) {
1410 case RPC_AUTH_REJECTEDCRED:
1411 case RPC_AUTH_REJECTEDVERF:
1412 case RPCSEC_GSS_CREDPROBLEM:
1413 case RPCSEC_GSS_CTXPROBLEM:
1414 if (!task->tk_cred_retry)
1416 task->tk_cred_retry--;
1417 dprintk("RPC: %5u %s: retry stale creds\n",
1418 task->tk_pid, __FUNCTION__);
1419 rpcauth_invalcred(task);
1420 /* Ensure we obtain a new XID! */
1422 task->tk_action = call_refresh;
1424 case RPC_AUTH_BADCRED:
1425 case RPC_AUTH_BADVERF:
1426 /* possibly garbled cred/verf? */
1427 if (!task->tk_garb_retry)
1429 task->tk_garb_retry--;
1430 dprintk("RPC: %5u %s: retry garbled creds\n",
1431 task->tk_pid, __FUNCTION__);
1432 task->tk_action = call_bind;
1434 case RPC_AUTH_TOOWEAK:
1435 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1436 "authentication.\n", task->tk_client->cl_server);
1439 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1440 task->tk_pid, __FUNCTION__, n);
1443 dprintk("RPC: %5u %s: call rejected %d\n",
1444 task->tk_pid, __FUNCTION__, n);
1447 if (!(p = rpcauth_checkverf(task, p))) {
1448 dprintk("RPC: %5u %s: auth check failed\n",
1449 task->tk_pid, __FUNCTION__);
1450 goto out_garbage; /* bad verifier, retry */
1452 len = p - (__be32 *)iov->iov_base - 1;
1455 switch ((n = ntohl(*p++))) {
1458 case RPC_PROG_UNAVAIL:
1459 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1460 task->tk_pid, __FUNCTION__,
1461 (unsigned int)task->tk_client->cl_prog,
1462 task->tk_client->cl_server);
1463 error = -EPFNOSUPPORT;
1465 case RPC_PROG_MISMATCH:
1466 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1467 "server %s\n", task->tk_pid, __FUNCTION__,
1468 (unsigned int)task->tk_client->cl_prog,
1469 (unsigned int)task->tk_client->cl_vers,
1470 task->tk_client->cl_server);
1471 error = -EPROTONOSUPPORT;
1473 case RPC_PROC_UNAVAIL:
1474 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1475 "version %u on server %s\n",
1476 task->tk_pid, __FUNCTION__,
1477 task->tk_msg.rpc_proc,
1478 task->tk_client->cl_prog,
1479 task->tk_client->cl_vers,
1480 task->tk_client->cl_server);
1481 error = -EOPNOTSUPP;
1483 case RPC_GARBAGE_ARGS:
1484 dprintk("RPC: %5u %s: server saw garbage\n",
1485 task->tk_pid, __FUNCTION__);
1488 dprintk("RPC: %5u %s: server accept status: %x\n",
1489 task->tk_pid, __FUNCTION__, n);
1494 task->tk_client->cl_stats->rpcgarbage++;
1495 if (task->tk_garb_retry) {
1496 task->tk_garb_retry--;
1497 dprintk("RPC: %5u %s: retrying\n",
1498 task->tk_pid, __FUNCTION__);
1499 task->tk_action = call_bind;
1501 return ERR_PTR(-EAGAIN);
1506 rpc_exit(task, error);
1507 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1508 __FUNCTION__, error);
1509 return ERR_PTR(error);
1511 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1516 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1521 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1526 static struct rpc_procinfo rpcproc_null = {
1527 .p_encode = rpcproc_encode_null,
1528 .p_decode = rpcproc_decode_null,
1531 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1533 struct rpc_message msg = {
1534 .rpc_proc = &rpcproc_null,
1537 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1538 err = rpc_call_sync(clnt, &msg, flags);
1539 put_rpccred(msg.rpc_cred);
1543 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1545 struct rpc_message msg = {
1546 .rpc_proc = &rpcproc_null,
1549 struct rpc_task_setup task_setup_data = {
1551 .rpc_message = &msg,
1552 .callback_ops = &rpc_default_ops,
1555 return rpc_run_task(&task_setup_data);
1557 EXPORT_SYMBOL_GPL(rpc_call_null);
1560 void rpc_show_tasks(void)
1562 struct rpc_clnt *clnt;
1565 spin_lock(&rpc_client_lock);
1566 if (list_empty(&all_clients))
1568 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1569 "-rpcwait -action- ---ops--\n");
1570 list_for_each_entry(clnt, &all_clients, cl_clients) {
1571 if (list_empty(&clnt->cl_tasks))
1573 spin_lock(&clnt->cl_lock);
1574 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1575 const char *rpc_waitq = "none";
1578 if (t->tk_msg.rpc_proc)
1579 proc = t->tk_msg.rpc_proc->p_proc;
1583 if (RPC_IS_QUEUED(t))
1584 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1586 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1588 t->tk_flags, t->tk_status,
1590 (t->tk_client ? t->tk_client->cl_prog : 0),
1591 t->tk_rqstp, t->tk_timeout,
1593 t->tk_action, t->tk_ops);
1595 spin_unlock(&clnt->cl_lock);
1598 spin_unlock(&rpc_client_lock);