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 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
684 struct rpc_xprt *xprt = clnt->cl_xprt;
686 if (xprt->address_strings[format] != NULL)
687 return xprt->address_strings[format];
689 return "unprintable";
691 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
694 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
696 struct rpc_xprt *xprt = clnt->cl_xprt;
697 if (xprt->ops->set_buffer_size)
698 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
700 EXPORT_SYMBOL_GPL(rpc_setbufsize);
703 * Return size of largest payload RPC client can support, in bytes
705 * For stream transports, this is one RPC record fragment (see RFC
706 * 1831), as we don't support multi-record requests yet. For datagram
707 * transports, this is the size of an IP packet minus the IP, UDP, and
710 size_t rpc_max_payload(struct rpc_clnt *clnt)
712 return clnt->cl_xprt->max_payload;
714 EXPORT_SYMBOL_GPL(rpc_max_payload);
717 * rpc_force_rebind - force transport to check that remote port is unchanged
718 * @clnt: client to rebind
721 void rpc_force_rebind(struct rpc_clnt *clnt)
723 if (clnt->cl_autobind)
724 xprt_clear_bound(clnt->cl_xprt);
726 EXPORT_SYMBOL_GPL(rpc_force_rebind);
729 * Restart an (async) RPC call. Usually called from within the
733 rpc_restart_call(struct rpc_task *task)
735 if (RPC_ASSASSINATED(task))
738 task->tk_action = call_start;
740 EXPORT_SYMBOL_GPL(rpc_restart_call);
745 * Other FSM states can be visited zero or more times, but
746 * this state is visited exactly once for each RPC.
749 call_start(struct rpc_task *task)
751 struct rpc_clnt *clnt = task->tk_client;
753 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
754 clnt->cl_protname, clnt->cl_vers,
755 task->tk_msg.rpc_proc->p_proc,
756 (RPC_IS_ASYNC(task) ? "async" : "sync"));
758 /* Increment call count */
759 task->tk_msg.rpc_proc->p_count++;
760 clnt->cl_stats->rpccnt++;
761 task->tk_action = call_reserve;
765 * 1. Reserve an RPC call slot
768 call_reserve(struct rpc_task *task)
772 if (!rpcauth_uptodatecred(task)) {
773 task->tk_action = call_refresh;
778 task->tk_action = call_reserveresult;
783 * 1b. Grok the result of xprt_reserve()
786 call_reserveresult(struct rpc_task *task)
788 int status = task->tk_status;
793 * After a call to xprt_reserve(), we must have either
794 * a request slot or else an error status.
798 if (task->tk_rqstp) {
799 task->tk_action = call_allocate;
803 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
804 __FUNCTION__, status);
805 rpc_exit(task, -EIO);
810 * Even though there was an error, we may have acquired
811 * a request slot somehow. Make sure not to leak it.
813 if (task->tk_rqstp) {
814 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
815 __FUNCTION__, status);
820 case -EAGAIN: /* woken up; retry */
821 task->tk_action = call_reserve;
823 case -EIO: /* probably a shutdown */
826 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
827 __FUNCTION__, status);
830 rpc_exit(task, status);
834 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
835 * (Note: buffer memory is freed in xprt_release).
838 call_allocate(struct rpc_task *task)
840 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
841 struct rpc_rqst *req = task->tk_rqstp;
842 struct rpc_xprt *xprt = task->tk_xprt;
843 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
848 task->tk_action = call_bind;
853 if (proc->p_proc != 0) {
854 BUG_ON(proc->p_arglen == 0);
855 if (proc->p_decode != NULL)
856 BUG_ON(proc->p_replen == 0);
860 * Calculate the size (in quads) of the RPC call
861 * and reply headers, and convert both values
864 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
865 req->rq_callsize <<= 2;
866 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
867 req->rq_rcvsize <<= 2;
869 req->rq_buffer = xprt->ops->buf_alloc(task,
870 req->rq_callsize + req->rq_rcvsize);
871 if (req->rq_buffer != NULL)
874 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
876 if (RPC_IS_ASYNC(task) || !signalled()) {
877 task->tk_action = call_allocate;
878 rpc_delay(task, HZ>>4);
882 rpc_exit(task, -ERESTARTSYS);
886 rpc_task_need_encode(struct rpc_task *task)
888 return task->tk_rqstp->rq_snd_buf.len == 0;
892 rpc_task_force_reencode(struct rpc_task *task)
894 task->tk_rqstp->rq_snd_buf.len = 0;
898 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
900 buf->head[0].iov_base = start;
901 buf->head[0].iov_len = len;
902 buf->tail[0].iov_len = 0;
910 * 3. Encode arguments of an RPC call
913 call_encode(struct rpc_task *task)
915 struct rpc_rqst *req = task->tk_rqstp;
921 rpc_xdr_buf_init(&req->rq_snd_buf,
924 rpc_xdr_buf_init(&req->rq_rcv_buf,
925 (char *)req->rq_buffer + req->rq_callsize,
928 /* Encode header and provided arguments */
929 encode = task->tk_msg.rpc_proc->p_encode;
930 if (!(p = call_header(task))) {
931 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
932 rpc_exit(task, -EIO);
938 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
939 task->tk_msg.rpc_argp);
940 if (task->tk_status == -ENOMEM) {
941 /* XXX: Is this sane? */
942 rpc_delay(task, 3*HZ);
943 task->tk_status = -EAGAIN;
948 * 4. Get the server port number if not yet set
951 call_bind(struct rpc_task *task)
953 struct rpc_xprt *xprt = task->tk_xprt;
957 task->tk_action = call_connect;
958 if (!xprt_bound(xprt)) {
959 task->tk_action = call_bind_status;
960 task->tk_timeout = xprt->bind_timeout;
961 xprt->ops->rpcbind(task);
966 * 4a. Sort out bind result
969 call_bind_status(struct rpc_task *task)
973 if (task->tk_status >= 0) {
976 task->tk_action = call_connect;
980 switch (task->tk_status) {
982 dprintk("RPC: %5u rpcbind waiting for another request "
983 "to finish\n", task->tk_pid);
984 /* avoid busy-waiting here -- could be a network outage. */
985 rpc_delay(task, 5*HZ);
988 dprintk("RPC: %5u remote rpcbind: RPC program/version "
989 "unavailable\n", task->tk_pid);
990 /* fail immediately if this is an RPC ping */
991 if (task->tk_msg.rpc_proc->p_proc == 0) {
992 status = -EOPNOTSUPP;
995 rpc_delay(task, 3*HZ);
998 dprintk("RPC: %5u rpcbind request timed out\n",
1002 /* server doesn't support any rpcbind version we know of */
1003 dprintk("RPC: %5u remote rpcbind service unavailable\n",
1006 case -EPROTONOSUPPORT:
1007 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1009 task->tk_status = 0;
1010 task->tk_action = call_bind;
1013 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1014 task->tk_pid, -task->tk_status);
1017 rpc_exit(task, status);
1021 task->tk_action = call_timeout;
1025 * 4b. Connect to the RPC server
1028 call_connect(struct rpc_task *task)
1030 struct rpc_xprt *xprt = task->tk_xprt;
1032 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1034 (xprt_connected(xprt) ? "is" : "is not"));
1036 task->tk_action = call_transmit;
1037 if (!xprt_connected(xprt)) {
1038 task->tk_action = call_connect_status;
1039 if (task->tk_status < 0)
1046 * 4c. Sort out connect result
1049 call_connect_status(struct rpc_task *task)
1051 struct rpc_clnt *clnt = task->tk_client;
1052 int status = task->tk_status;
1054 dprint_status(task);
1056 task->tk_status = 0;
1058 clnt->cl_stats->netreconn++;
1059 task->tk_action = call_transmit;
1063 /* Something failed: remote service port may have changed */
1064 rpc_force_rebind(clnt);
1069 task->tk_action = call_bind;
1070 if (!RPC_IS_SOFT(task))
1072 /* if soft mounted, test if we've timed out */
1074 task->tk_action = call_timeout;
1077 rpc_exit(task, -EIO);
1081 * 5. Transmit the RPC request, and wait for reply
1084 call_transmit(struct rpc_task *task)
1086 dprint_status(task);
1088 task->tk_action = call_status;
1089 if (task->tk_status < 0)
1091 task->tk_status = xprt_prepare_transmit(task);
1092 if (task->tk_status != 0)
1094 task->tk_action = call_transmit_status;
1095 /* Encode here so that rpcsec_gss can use correct sequence number. */
1096 if (rpc_task_need_encode(task)) {
1097 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1099 /* Did the encode result in an error condition? */
1100 if (task->tk_status != 0)
1103 xprt_transmit(task);
1104 if (task->tk_status < 0)
1107 * On success, ensure that we call xprt_end_transmit() before sleeping
1108 * in order to allow access to the socket to other RPC requests.
1110 call_transmit_status(task);
1111 if (task->tk_msg.rpc_proc->p_decode != NULL)
1113 task->tk_action = rpc_exit_task;
1114 rpc_wake_up_task(task);
1118 * 5a. Handle cleanup after a transmission
1121 call_transmit_status(struct rpc_task *task)
1123 task->tk_action = call_status;
1125 * Special case: if we've been waiting on the socket's write_space()
1126 * callback, then don't call xprt_end_transmit().
1128 if (task->tk_status == -EAGAIN)
1130 xprt_end_transmit(task);
1131 rpc_task_force_reencode(task);
1135 * 6. Sort out the RPC call status
1138 call_status(struct rpc_task *task)
1140 struct rpc_clnt *clnt = task->tk_client;
1141 struct rpc_rqst *req = task->tk_rqstp;
1144 if (req->rq_received > 0 && !req->rq_bytes_sent)
1145 task->tk_status = req->rq_received;
1147 dprint_status(task);
1149 status = task->tk_status;
1151 task->tk_action = call_decode;
1155 task->tk_status = 0;
1161 * Delay any retries for 3 seconds, then handle as if it
1164 rpc_delay(task, 3*HZ);
1166 task->tk_action = call_timeout;
1167 if (task->tk_client->cl_discrtry)
1168 xprt_force_disconnect(task->tk_xprt);
1172 rpc_force_rebind(clnt);
1173 task->tk_action = call_bind;
1176 task->tk_action = call_transmit;
1179 /* shutdown or soft timeout */
1180 rpc_exit(task, status);
1183 printk("%s: RPC call returned error %d\n",
1184 clnt->cl_protname, -status);
1185 rpc_exit(task, status);
1190 * 6a. Handle RPC timeout
1191 * We do not release the request slot, so we keep using the
1192 * same XID for all retransmits.
1195 call_timeout(struct rpc_task *task)
1197 struct rpc_clnt *clnt = task->tk_client;
1199 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1200 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1204 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1205 task->tk_timeouts++;
1207 if (RPC_IS_SOFT(task)) {
1208 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1209 clnt->cl_protname, clnt->cl_server);
1210 rpc_exit(task, -EIO);
1214 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1215 task->tk_flags |= RPC_CALL_MAJORSEEN;
1216 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1217 clnt->cl_protname, clnt->cl_server);
1219 rpc_force_rebind(clnt);
1222 clnt->cl_stats->rpcretrans++;
1223 task->tk_action = call_bind;
1224 task->tk_status = 0;
1228 * 7. Decode the RPC reply
1231 call_decode(struct rpc_task *task)
1233 struct rpc_clnt *clnt = task->tk_client;
1234 struct rpc_rqst *req = task->tk_rqstp;
1235 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1238 dprintk("RPC: %5u call_decode (status %d)\n",
1239 task->tk_pid, task->tk_status);
1241 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1242 printk(KERN_NOTICE "%s: server %s OK\n",
1243 clnt->cl_protname, clnt->cl_server);
1244 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1247 if (task->tk_status < 12) {
1248 if (!RPC_IS_SOFT(task)) {
1249 task->tk_action = call_bind;
1250 clnt->cl_stats->rpcretrans++;
1253 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1254 clnt->cl_protname, task->tk_status);
1255 task->tk_action = call_timeout;
1260 * Ensure that we see all writes made by xprt_complete_rqst()
1261 * before it changed req->rq_received.
1264 req->rq_rcv_buf.len = req->rq_private_buf.len;
1266 /* Check that the softirq receive buffer is valid */
1267 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1268 sizeof(req->rq_rcv_buf)) != 0);
1270 /* Verify the RPC header */
1271 p = call_verify(task);
1273 if (p == ERR_PTR(-EAGAIN))
1278 task->tk_action = rpc_exit_task;
1281 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1282 task->tk_msg.rpc_resp);
1284 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1288 req->rq_received = req->rq_private_buf.len = 0;
1289 task->tk_status = 0;
1290 if (task->tk_client->cl_discrtry)
1291 xprt_force_disconnect(task->tk_xprt);
1295 * 8. Refresh the credentials if rejected by the server
1298 call_refresh(struct rpc_task *task)
1300 dprint_status(task);
1302 task->tk_action = call_refreshresult;
1303 task->tk_status = 0;
1304 task->tk_client->cl_stats->rpcauthrefresh++;
1305 rpcauth_refreshcred(task);
1309 * 8a. Process the results of a credential refresh
1312 call_refreshresult(struct rpc_task *task)
1314 int status = task->tk_status;
1316 dprint_status(task);
1318 task->tk_status = 0;
1319 task->tk_action = call_reserve;
1320 if (status >= 0 && rpcauth_uptodatecred(task))
1322 if (status == -EACCES) {
1323 rpc_exit(task, -EACCES);
1326 task->tk_action = call_refresh;
1327 if (status != -ETIMEDOUT)
1328 rpc_delay(task, 3*HZ);
1333 * Call header serialization
1336 call_header(struct rpc_task *task)
1338 struct rpc_clnt *clnt = task->tk_client;
1339 struct rpc_rqst *req = task->tk_rqstp;
1340 __be32 *p = req->rq_svec[0].iov_base;
1342 /* FIXME: check buffer size? */
1344 p = xprt_skip_transport_header(task->tk_xprt, p);
1345 *p++ = req->rq_xid; /* XID */
1346 *p++ = htonl(RPC_CALL); /* CALL */
1347 *p++ = htonl(RPC_VERSION); /* RPC version */
1348 *p++ = htonl(clnt->cl_prog); /* program number */
1349 *p++ = htonl(clnt->cl_vers); /* program version */
1350 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1351 p = rpcauth_marshcred(task, p);
1352 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1357 * Reply header verification
1360 call_verify(struct rpc_task *task)
1362 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1363 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1364 __be32 *p = iov->iov_base;
1366 int error = -EACCES;
1368 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1369 /* RFC-1014 says that the representation of XDR data must be a
1370 * multiple of four bytes
1371 * - if it isn't pointer subtraction in the NFS client may give
1374 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1375 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1376 task->tk_rqstp->rq_rcv_buf.len);
1381 p += 1; /* skip XID */
1383 if ((n = ntohl(*p++)) != RPC_REPLY) {
1384 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1385 task->tk_pid, __FUNCTION__, n);
1388 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1391 switch ((n = ntohl(*p++))) {
1392 case RPC_AUTH_ERROR:
1395 dprintk("RPC: %5u %s: RPC call version "
1397 task->tk_pid, __FUNCTION__);
1398 error = -EPROTONOSUPPORT;
1401 dprintk("RPC: %5u %s: RPC call rejected, "
1402 "unknown error: %x\n",
1403 task->tk_pid, __FUNCTION__, n);
1408 switch ((n = ntohl(*p++))) {
1409 case RPC_AUTH_REJECTEDCRED:
1410 case RPC_AUTH_REJECTEDVERF:
1411 case RPCSEC_GSS_CREDPROBLEM:
1412 case RPCSEC_GSS_CTXPROBLEM:
1413 if (!task->tk_cred_retry)
1415 task->tk_cred_retry--;
1416 dprintk("RPC: %5u %s: retry stale creds\n",
1417 task->tk_pid, __FUNCTION__);
1418 rpcauth_invalcred(task);
1419 /* Ensure we obtain a new XID! */
1421 task->tk_action = call_refresh;
1423 case RPC_AUTH_BADCRED:
1424 case RPC_AUTH_BADVERF:
1425 /* possibly garbled cred/verf? */
1426 if (!task->tk_garb_retry)
1428 task->tk_garb_retry--;
1429 dprintk("RPC: %5u %s: retry garbled creds\n",
1430 task->tk_pid, __FUNCTION__);
1431 task->tk_action = call_bind;
1433 case RPC_AUTH_TOOWEAK:
1434 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1435 "authentication.\n", task->tk_client->cl_server);
1438 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1439 task->tk_pid, __FUNCTION__, n);
1442 dprintk("RPC: %5u %s: call rejected %d\n",
1443 task->tk_pid, __FUNCTION__, n);
1446 if (!(p = rpcauth_checkverf(task, p))) {
1447 dprintk("RPC: %5u %s: auth check failed\n",
1448 task->tk_pid, __FUNCTION__);
1449 goto out_garbage; /* bad verifier, retry */
1451 len = p - (__be32 *)iov->iov_base - 1;
1454 switch ((n = ntohl(*p++))) {
1457 case RPC_PROG_UNAVAIL:
1458 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1459 task->tk_pid, __FUNCTION__,
1460 (unsigned int)task->tk_client->cl_prog,
1461 task->tk_client->cl_server);
1462 error = -EPFNOSUPPORT;
1464 case RPC_PROG_MISMATCH:
1465 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1466 "server %s\n", task->tk_pid, __FUNCTION__,
1467 (unsigned int)task->tk_client->cl_prog,
1468 (unsigned int)task->tk_client->cl_vers,
1469 task->tk_client->cl_server);
1470 error = -EPROTONOSUPPORT;
1472 case RPC_PROC_UNAVAIL:
1473 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1474 "version %u on server %s\n",
1475 task->tk_pid, __FUNCTION__,
1476 task->tk_msg.rpc_proc,
1477 task->tk_client->cl_prog,
1478 task->tk_client->cl_vers,
1479 task->tk_client->cl_server);
1480 error = -EOPNOTSUPP;
1482 case RPC_GARBAGE_ARGS:
1483 dprintk("RPC: %5u %s: server saw garbage\n",
1484 task->tk_pid, __FUNCTION__);
1487 dprintk("RPC: %5u %s: server accept status: %x\n",
1488 task->tk_pid, __FUNCTION__, n);
1493 task->tk_client->cl_stats->rpcgarbage++;
1494 if (task->tk_garb_retry) {
1495 task->tk_garb_retry--;
1496 dprintk("RPC: %5u %s: retrying\n",
1497 task->tk_pid, __FUNCTION__);
1498 task->tk_action = call_bind;
1500 return ERR_PTR(-EAGAIN);
1505 rpc_exit(task, error);
1506 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1507 __FUNCTION__, error);
1508 return ERR_PTR(error);
1510 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1515 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1520 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1525 static struct rpc_procinfo rpcproc_null = {
1526 .p_encode = rpcproc_encode_null,
1527 .p_decode = rpcproc_decode_null,
1530 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1532 struct rpc_message msg = {
1533 .rpc_proc = &rpcproc_null,
1536 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1537 err = rpc_call_sync(clnt, &msg, flags);
1538 put_rpccred(msg.rpc_cred);
1542 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1544 struct rpc_message msg = {
1545 .rpc_proc = &rpcproc_null,
1548 struct rpc_task_setup task_setup_data = {
1550 .rpc_message = &msg,
1551 .callback_ops = &rpc_default_ops,
1554 return rpc_run_task(&task_setup_data);
1556 EXPORT_SYMBOL_GPL(rpc_call_null);
1559 void rpc_show_tasks(void)
1561 struct rpc_clnt *clnt;
1564 spin_lock(&rpc_client_lock);
1565 if (list_empty(&all_clients))
1567 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1568 "-rpcwait -action- ---ops--\n");
1569 list_for_each_entry(clnt, &all_clients, cl_clients) {
1570 if (list_empty(&clnt->cl_tasks))
1572 spin_lock(&clnt->cl_lock);
1573 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1574 const char *rpc_waitq = "none";
1577 if (t->tk_msg.rpc_proc)
1578 proc = t->tk_msg.rpc_proc->p_proc;
1582 if (RPC_IS_QUEUED(t))
1583 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1585 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1587 t->tk_flags, t->tk_status,
1589 (t->tk_client ? t->tk_client->cl_prog : 0),
1590 t->tk_rqstp, t->tk_timeout,
1592 t->tk_action, t->tk_ops);
1594 spin_unlock(&clnt->cl_lock);
1597 spin_unlock(&rpc_client_lock);