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>
34 #include <linux/sunrpc/clnt.h>
35 #include <linux/sunrpc/rpc_pipe_fs.h>
36 #include <linux/sunrpc/metrics.h>
40 # define RPCDBG_FACILITY RPCDBG_CALL
43 #define dprint_status(t) \
44 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
45 __FUNCTION__, t->tk_status)
48 * All RPC clients are linked into this list
50 static LIST_HEAD(all_clients);
51 static DEFINE_SPINLOCK(rpc_client_lock);
53 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
56 static void call_start(struct rpc_task *task);
57 static void call_reserve(struct rpc_task *task);
58 static void call_reserveresult(struct rpc_task *task);
59 static void call_allocate(struct rpc_task *task);
60 static void call_encode(struct rpc_task *task);
61 static void call_decode(struct rpc_task *task);
62 static void call_bind(struct rpc_task *task);
63 static void call_bind_status(struct rpc_task *task);
64 static void call_transmit(struct rpc_task *task);
65 static void call_status(struct rpc_task *task);
66 static void call_transmit_status(struct rpc_task *task);
67 static void call_refresh(struct rpc_task *task);
68 static void call_refreshresult(struct rpc_task *task);
69 static void call_timeout(struct rpc_task *task);
70 static void call_connect(struct rpc_task *task);
71 static void call_connect_status(struct rpc_task *task);
72 static __be32 * call_header(struct rpc_task *task);
73 static __be32 * call_verify(struct rpc_task *task);
75 static int rpc_ping(struct rpc_clnt *clnt, int flags);
77 static void rpc_register_client(struct rpc_clnt *clnt)
79 spin_lock(&rpc_client_lock);
80 list_add(&clnt->cl_clients, &all_clients);
81 spin_unlock(&rpc_client_lock);
84 static void rpc_unregister_client(struct rpc_clnt *clnt)
86 spin_lock(&rpc_client_lock);
87 list_del(&clnt->cl_clients);
88 spin_unlock(&rpc_client_lock);
92 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
94 static uint32_t clntid;
97 clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
98 clnt->cl_dentry = ERR_PTR(-ENOENT);
102 clnt->cl_vfsmnt = rpc_get_mount();
103 if (IS_ERR(clnt->cl_vfsmnt))
104 return PTR_ERR(clnt->cl_vfsmnt);
107 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
108 "%s/clnt%x", dir_name,
109 (unsigned int)clntid++);
110 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
111 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
112 if (!IS_ERR(clnt->cl_dentry))
114 error = PTR_ERR(clnt->cl_dentry);
115 if (error != -EEXIST) {
116 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
117 clnt->cl_pathname, error);
124 static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor)
126 struct rpc_version *version;
127 struct rpc_clnt *clnt = NULL;
128 struct rpc_auth *auth;
132 /* sanity check the name before trying to print it */
134 len = strlen(servname);
135 if (len > RPC_MAXNETNAMELEN)
139 dprintk("RPC: creating %s client for %s (xprt %p)\n",
140 program->name, servname, xprt);
148 if (vers >= program->nrvers || !(version = program->version[vers]))
152 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
155 clnt->cl_parent = clnt;
157 clnt->cl_server = clnt->cl_inline_name;
158 if (len > sizeof(clnt->cl_inline_name)) {
159 char *buf = kmalloc(len, GFP_KERNEL);
161 clnt->cl_server = buf;
163 len = sizeof(clnt->cl_inline_name);
165 strlcpy(clnt->cl_server, servname, len);
167 clnt->cl_xprt = xprt;
168 clnt->cl_procinfo = version->procs;
169 clnt->cl_maxproc = version->nrprocs;
170 clnt->cl_protname = program->name;
171 clnt->cl_prog = program->number;
172 clnt->cl_vers = version->number;
173 clnt->cl_stats = program->stats;
174 clnt->cl_metrics = rpc_alloc_iostats(clnt);
176 if (clnt->cl_metrics == NULL)
178 clnt->cl_program = program;
179 INIT_LIST_HEAD(&clnt->cl_tasks);
180 spin_lock_init(&clnt->cl_lock);
182 if (!xprt_bound(clnt->cl_xprt))
183 clnt->cl_autobind = 1;
185 clnt->cl_rtt = &clnt->cl_rtt_default;
186 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
188 kref_init(&clnt->cl_kref);
190 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
194 auth = rpcauth_create(flavor, clnt);
196 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
202 /* save the nodename */
203 clnt->cl_nodelen = strlen(utsname()->nodename);
204 if (clnt->cl_nodelen > UNX_MAXNODENAME)
205 clnt->cl_nodelen = UNX_MAXNODENAME;
206 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
207 rpc_register_client(clnt);
211 if (!IS_ERR(clnt->cl_dentry)) {
212 rpc_rmdir(clnt->cl_dentry);
216 rpc_free_iostats(clnt->cl_metrics);
218 if (clnt->cl_server != clnt->cl_inline_name)
219 kfree(clnt->cl_server);
230 * rpc_create - create an RPC client and transport with one call
231 * @args: rpc_clnt create argument structure
233 * Creates and initializes an RPC transport and an RPC client.
235 * It can ping the server in order to determine if it is up, and to see if
236 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
237 * this behavior so asynchronous tasks can also use rpc_create.
239 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
241 struct rpc_xprt *xprt;
242 struct rpc_clnt *clnt;
243 struct xprt_create xprtargs = {
244 .ident = args->protocol,
245 .srcaddr = args->saddress,
246 .dstaddr = args->address,
247 .addrlen = args->addrsize,
248 .timeout = args->timeout
252 xprt = xprt_create_transport(&xprtargs);
254 return (struct rpc_clnt *)xprt;
257 * If the caller chooses not to specify a hostname, whip
258 * up a string representation of the passed-in address.
260 if (args->servername == NULL) {
261 struct sockaddr_in *addr =
262 (struct sockaddr_in *) args->address;
263 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
264 NIPQUAD(addr->sin_addr.s_addr));
265 args->servername = servername;
269 * By default, kernel RPC client connects from a reserved port.
270 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
271 * but it is always enabled for rpciod, which handles the connect
275 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
278 clnt = rpc_new_client(xprt, args->servername, args->program,
279 args->version, args->authflavor);
283 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
284 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
286 rpc_shutdown_client(clnt);
291 clnt->cl_softrtry = 1;
292 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
293 clnt->cl_softrtry = 0;
295 if (args->flags & RPC_CLNT_CREATE_INTR)
297 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
298 clnt->cl_autobind = 1;
299 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
300 clnt->cl_discrtry = 1;
304 EXPORT_SYMBOL_GPL(rpc_create);
307 * This function clones the RPC client structure. It allows us to share the
308 * same transport while varying parameters such as the authentication
312 rpc_clone_client(struct rpc_clnt *clnt)
314 struct rpc_clnt *new;
317 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
320 new->cl_parent = clnt;
321 /* Turn off autobind on clones */
322 new->cl_autobind = 0;
323 INIT_LIST_HEAD(&new->cl_tasks);
324 spin_lock_init(&new->cl_lock);
325 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
326 new->cl_metrics = rpc_alloc_iostats(clnt);
327 if (new->cl_metrics == NULL)
329 kref_init(&new->cl_kref);
330 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
334 atomic_inc(&new->cl_auth->au_count);
335 xprt_get(clnt->cl_xprt);
336 kref_get(&clnt->cl_kref);
337 rpc_register_client(new);
341 rpc_free_iostats(new->cl_metrics);
345 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
348 EXPORT_SYMBOL_GPL(rpc_clone_client);
351 * Properly shut down an RPC client, terminating all outstanding
354 void rpc_shutdown_client(struct rpc_clnt *clnt)
356 dprintk("RPC: shutting down %s client for %s\n",
357 clnt->cl_protname, clnt->cl_server);
359 while (!list_empty(&clnt->cl_tasks)) {
360 rpc_killall_tasks(clnt);
361 wait_event_timeout(destroy_wait,
362 list_empty(&clnt->cl_tasks), 1*HZ);
365 rpc_release_client(clnt);
367 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
373 rpc_free_client(struct kref *kref)
375 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
377 dprintk("RPC: destroying %s client for %s\n",
378 clnt->cl_protname, clnt->cl_server);
379 if (!IS_ERR(clnt->cl_dentry)) {
380 rpc_rmdir(clnt->cl_dentry);
383 if (clnt->cl_parent != clnt) {
384 rpc_release_client(clnt->cl_parent);
387 if (clnt->cl_server != clnt->cl_inline_name)
388 kfree(clnt->cl_server);
390 rpc_unregister_client(clnt);
391 rpc_free_iostats(clnt->cl_metrics);
392 clnt->cl_metrics = NULL;
393 xprt_put(clnt->cl_xprt);
402 rpc_free_auth(struct kref *kref)
404 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
406 if (clnt->cl_auth == NULL) {
407 rpc_free_client(kref);
412 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
413 * release remaining GSS contexts. This mechanism ensures
414 * that it can do so safely.
417 rpcauth_release(clnt->cl_auth);
418 clnt->cl_auth = NULL;
419 kref_put(kref, rpc_free_client);
423 * Release reference to the RPC client
426 rpc_release_client(struct rpc_clnt *clnt)
428 dprintk("RPC: rpc_release_client(%p)\n", clnt);
430 if (list_empty(&clnt->cl_tasks))
431 wake_up(&destroy_wait);
432 kref_put(&clnt->cl_kref, rpc_free_auth);
436 * rpc_bind_new_program - bind a new RPC program to an existing client
437 * @old - old rpc_client
438 * @program - rpc program to set
439 * @vers - rpc program version
441 * Clones the rpc client and sets up a new RPC program. This is mainly
442 * of use for enabling different RPC programs to share the same transport.
443 * The Sun NFSv2/v3 ACL protocol can do this.
445 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
446 struct rpc_program *program,
449 struct rpc_clnt *clnt;
450 struct rpc_version *version;
453 BUG_ON(vers >= program->nrvers || !program->version[vers]);
454 version = program->version[vers];
455 clnt = rpc_clone_client(old);
458 clnt->cl_procinfo = version->procs;
459 clnt->cl_maxproc = version->nrprocs;
460 clnt->cl_protname = program->name;
461 clnt->cl_prog = program->number;
462 clnt->cl_vers = version->number;
463 clnt->cl_stats = program->stats;
464 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
466 rpc_shutdown_client(clnt);
472 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
475 * Default callback for async RPC calls
478 rpc_default_callback(struct rpc_task *task, void *data)
482 static const struct rpc_call_ops rpc_default_ops = {
483 .rpc_call_done = rpc_default_callback,
487 * Export the signal mask handling for synchronous code that
488 * sleeps on RPC calls
490 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
492 static void rpc_save_sigmask(sigset_t *oldset, int intr)
494 unsigned long sigallow = sigmask(SIGKILL);
497 /* Block all signals except those listed in sigallow */
499 sigallow |= RPC_INTR_SIGNALS;
500 siginitsetinv(&sigmask, sigallow);
501 sigprocmask(SIG_BLOCK, &sigmask, oldset);
504 static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
506 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
509 static inline void rpc_restore_sigmask(sigset_t *oldset)
511 sigprocmask(SIG_SETMASK, oldset, NULL);
514 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
516 rpc_save_sigmask(oldset, clnt->cl_intr);
518 EXPORT_SYMBOL_GPL(rpc_clnt_sigmask);
520 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
522 rpc_restore_sigmask(oldset);
524 EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask);
527 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
528 * @task_setup_data: pointer to task initialisation data
530 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
532 struct rpc_task *task, *ret;
535 task = rpc_new_task(task_setup_data);
537 rpc_release_calldata(task_setup_data->callback_ops,
538 task_setup_data->callback_data);
539 return ERR_PTR(-ENOMEM);
542 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
543 rpc_task_sigmask(task, &oldset);
544 if (task_setup_data->rpc_message != NULL) {
545 rpc_call_setup(task, task_setup_data->rpc_message, 0);
546 if (task->tk_status != 0) {
547 ret = ERR_PTR(task->tk_status);
552 atomic_inc(&task->tk_count);
556 rpc_restore_sigmask(&oldset);
559 EXPORT_SYMBOL_GPL(rpc_run_task);
562 * rpc_call_sync - Perform a synchronous RPC call
563 * @clnt: pointer to RPC client
564 * @msg: RPC call parameters
565 * @flags: RPC call flags
567 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
569 struct rpc_task *task;
570 struct rpc_task_setup task_setup_data = {
573 .callback_ops = &rpc_default_ops,
578 BUG_ON(flags & RPC_TASK_ASYNC);
580 task = rpc_run_task(&task_setup_data);
582 return PTR_ERR(task);
583 status = task->tk_status;
587 EXPORT_SYMBOL_GPL(rpc_call_sync);
590 * rpc_call_async - Perform an asynchronous RPC call
591 * @clnt: pointer to RPC client
592 * @msg: RPC call parameters
593 * @flags: RPC call flags
595 * @data: user call data
598 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
599 const struct rpc_call_ops *tk_ops, void *data)
601 struct rpc_task *task;
602 struct rpc_task_setup task_setup_data = {
605 .callback_ops = tk_ops,
606 .callback_data = data,
607 .flags = flags|RPC_TASK_ASYNC,
610 task = rpc_run_task(&task_setup_data);
612 return PTR_ERR(task);
616 EXPORT_SYMBOL_GPL(rpc_call_async);
619 rpc_call_setup(struct rpc_task *task, const struct rpc_message *msg, int flags)
622 task->tk_flags |= flags;
623 /* Bind the user cred */
624 if (task->tk_msg.rpc_cred != NULL)
625 rpcauth_holdcred(task);
627 rpcauth_bindcred(task);
629 if (task->tk_status == 0)
630 task->tk_action = call_start;
632 task->tk_action = rpc_exit_task;
634 EXPORT_SYMBOL_GPL(rpc_call_setup);
637 * rpc_peeraddr - extract remote peer address from clnt's xprt
638 * @clnt: RPC client structure
639 * @buf: target buffer
640 * @size: length of target buffer
642 * Returns the number of bytes that are actually in the stored address.
644 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
647 struct rpc_xprt *xprt = clnt->cl_xprt;
649 bytes = sizeof(xprt->addr);
652 memcpy(buf, &clnt->cl_xprt->addr, bytes);
653 return xprt->addrlen;
655 EXPORT_SYMBOL_GPL(rpc_peeraddr);
658 * rpc_peeraddr2str - return remote peer address in printable format
659 * @clnt: RPC client structure
660 * @format: address format
663 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
665 struct rpc_xprt *xprt = clnt->cl_xprt;
667 if (xprt->address_strings[format] != NULL)
668 return xprt->address_strings[format];
670 return "unprintable";
672 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
675 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
677 struct rpc_xprt *xprt = clnt->cl_xprt;
678 if (xprt->ops->set_buffer_size)
679 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
681 EXPORT_SYMBOL_GPL(rpc_setbufsize);
684 * Return size of largest payload RPC client can support, in bytes
686 * For stream transports, this is one RPC record fragment (see RFC
687 * 1831), as we don't support multi-record requests yet. For datagram
688 * transports, this is the size of an IP packet minus the IP, UDP, and
691 size_t rpc_max_payload(struct rpc_clnt *clnt)
693 return clnt->cl_xprt->max_payload;
695 EXPORT_SYMBOL_GPL(rpc_max_payload);
698 * rpc_force_rebind - force transport to check that remote port is unchanged
699 * @clnt: client to rebind
702 void rpc_force_rebind(struct rpc_clnt *clnt)
704 if (clnt->cl_autobind)
705 xprt_clear_bound(clnt->cl_xprt);
707 EXPORT_SYMBOL_GPL(rpc_force_rebind);
710 * Restart an (async) RPC call. Usually called from within the
714 rpc_restart_call(struct rpc_task *task)
716 if (RPC_ASSASSINATED(task))
719 task->tk_action = call_start;
721 EXPORT_SYMBOL_GPL(rpc_restart_call);
726 * Other FSM states can be visited zero or more times, but
727 * this state is visited exactly once for each RPC.
730 call_start(struct rpc_task *task)
732 struct rpc_clnt *clnt = task->tk_client;
734 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
735 clnt->cl_protname, clnt->cl_vers,
736 task->tk_msg.rpc_proc->p_proc,
737 (RPC_IS_ASYNC(task) ? "async" : "sync"));
739 /* Increment call count */
740 task->tk_msg.rpc_proc->p_count++;
741 clnt->cl_stats->rpccnt++;
742 task->tk_action = call_reserve;
746 * 1. Reserve an RPC call slot
749 call_reserve(struct rpc_task *task)
753 if (!rpcauth_uptodatecred(task)) {
754 task->tk_action = call_refresh;
759 task->tk_action = call_reserveresult;
764 * 1b. Grok the result of xprt_reserve()
767 call_reserveresult(struct rpc_task *task)
769 int status = task->tk_status;
774 * After a call to xprt_reserve(), we must have either
775 * a request slot or else an error status.
779 if (task->tk_rqstp) {
780 task->tk_action = call_allocate;
784 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
785 __FUNCTION__, status);
786 rpc_exit(task, -EIO);
791 * Even though there was an error, we may have acquired
792 * a request slot somehow. Make sure not to leak it.
794 if (task->tk_rqstp) {
795 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
796 __FUNCTION__, status);
801 case -EAGAIN: /* woken up; retry */
802 task->tk_action = call_reserve;
804 case -EIO: /* probably a shutdown */
807 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
808 __FUNCTION__, status);
811 rpc_exit(task, status);
815 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
816 * (Note: buffer memory is freed in xprt_release).
819 call_allocate(struct rpc_task *task)
821 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
822 struct rpc_rqst *req = task->tk_rqstp;
823 struct rpc_xprt *xprt = task->tk_xprt;
824 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
829 task->tk_action = call_bind;
834 if (proc->p_proc != 0) {
835 BUG_ON(proc->p_arglen == 0);
836 if (proc->p_decode != NULL)
837 BUG_ON(proc->p_replen == 0);
841 * Calculate the size (in quads) of the RPC call
842 * and reply headers, and convert both values
845 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
846 req->rq_callsize <<= 2;
847 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
848 req->rq_rcvsize <<= 2;
850 req->rq_buffer = xprt->ops->buf_alloc(task,
851 req->rq_callsize + req->rq_rcvsize);
852 if (req->rq_buffer != NULL)
855 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
857 if (RPC_IS_ASYNC(task) || !signalled()) {
858 task->tk_action = call_allocate;
859 rpc_delay(task, HZ>>4);
863 rpc_exit(task, -ERESTARTSYS);
867 rpc_task_need_encode(struct rpc_task *task)
869 return task->tk_rqstp->rq_snd_buf.len == 0;
873 rpc_task_force_reencode(struct rpc_task *task)
875 task->tk_rqstp->rq_snd_buf.len = 0;
879 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
881 buf->head[0].iov_base = start;
882 buf->head[0].iov_len = len;
883 buf->tail[0].iov_len = 0;
891 * 3. Encode arguments of an RPC call
894 call_encode(struct rpc_task *task)
896 struct rpc_rqst *req = task->tk_rqstp;
902 rpc_xdr_buf_init(&req->rq_snd_buf,
905 rpc_xdr_buf_init(&req->rq_rcv_buf,
906 (char *)req->rq_buffer + req->rq_callsize,
909 /* Encode header and provided arguments */
910 encode = task->tk_msg.rpc_proc->p_encode;
911 if (!(p = call_header(task))) {
912 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
913 rpc_exit(task, -EIO);
919 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
920 task->tk_msg.rpc_argp);
921 if (task->tk_status == -ENOMEM) {
922 /* XXX: Is this sane? */
923 rpc_delay(task, 3*HZ);
924 task->tk_status = -EAGAIN;
929 * 4. Get the server port number if not yet set
932 call_bind(struct rpc_task *task)
934 struct rpc_xprt *xprt = task->tk_xprt;
938 task->tk_action = call_connect;
939 if (!xprt_bound(xprt)) {
940 task->tk_action = call_bind_status;
941 task->tk_timeout = xprt->bind_timeout;
942 xprt->ops->rpcbind(task);
947 * 4a. Sort out bind result
950 call_bind_status(struct rpc_task *task)
954 if (task->tk_status >= 0) {
957 task->tk_action = call_connect;
961 switch (task->tk_status) {
963 dprintk("RPC: %5u rpcbind waiting for another request "
964 "to finish\n", task->tk_pid);
965 /* avoid busy-waiting here -- could be a network outage. */
966 rpc_delay(task, 5*HZ);
969 dprintk("RPC: %5u remote rpcbind: RPC program/version "
970 "unavailable\n", task->tk_pid);
971 /* fail immediately if this is an RPC ping */
972 if (task->tk_msg.rpc_proc->p_proc == 0) {
973 status = -EOPNOTSUPP;
976 rpc_delay(task, 3*HZ);
979 dprintk("RPC: %5u rpcbind request timed out\n",
983 /* server doesn't support any rpcbind version we know of */
984 dprintk("RPC: %5u remote rpcbind service unavailable\n",
987 case -EPROTONOSUPPORT:
988 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
991 task->tk_action = call_bind;
994 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
995 task->tk_pid, -task->tk_status);
998 rpc_exit(task, status);
1002 task->tk_action = call_timeout;
1006 * 4b. Connect to the RPC server
1009 call_connect(struct rpc_task *task)
1011 struct rpc_xprt *xprt = task->tk_xprt;
1013 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1015 (xprt_connected(xprt) ? "is" : "is not"));
1017 task->tk_action = call_transmit;
1018 if (!xprt_connected(xprt)) {
1019 task->tk_action = call_connect_status;
1020 if (task->tk_status < 0)
1027 * 4c. Sort out connect result
1030 call_connect_status(struct rpc_task *task)
1032 struct rpc_clnt *clnt = task->tk_client;
1033 int status = task->tk_status;
1035 dprint_status(task);
1037 task->tk_status = 0;
1039 clnt->cl_stats->netreconn++;
1040 task->tk_action = call_transmit;
1044 /* Something failed: remote service port may have changed */
1045 rpc_force_rebind(clnt);
1050 task->tk_action = call_bind;
1051 if (!RPC_IS_SOFT(task))
1053 /* if soft mounted, test if we've timed out */
1055 task->tk_action = call_timeout;
1058 rpc_exit(task, -EIO);
1062 * 5. Transmit the RPC request, and wait for reply
1065 call_transmit(struct rpc_task *task)
1067 dprint_status(task);
1069 task->tk_action = call_status;
1070 if (task->tk_status < 0)
1072 task->tk_status = xprt_prepare_transmit(task);
1073 if (task->tk_status != 0)
1075 task->tk_action = call_transmit_status;
1076 /* Encode here so that rpcsec_gss can use correct sequence number. */
1077 if (rpc_task_need_encode(task)) {
1078 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1080 /* Did the encode result in an error condition? */
1081 if (task->tk_status != 0)
1084 xprt_transmit(task);
1085 if (task->tk_status < 0)
1088 * On success, ensure that we call xprt_end_transmit() before sleeping
1089 * in order to allow access to the socket to other RPC requests.
1091 call_transmit_status(task);
1092 if (task->tk_msg.rpc_proc->p_decode != NULL)
1094 task->tk_action = rpc_exit_task;
1095 rpc_wake_up_task(task);
1099 * 5a. Handle cleanup after a transmission
1102 call_transmit_status(struct rpc_task *task)
1104 task->tk_action = call_status;
1106 * Special case: if we've been waiting on the socket's write_space()
1107 * callback, then don't call xprt_end_transmit().
1109 if (task->tk_status == -EAGAIN)
1111 xprt_end_transmit(task);
1112 rpc_task_force_reencode(task);
1116 * 6. Sort out the RPC call status
1119 call_status(struct rpc_task *task)
1121 struct rpc_clnt *clnt = task->tk_client;
1122 struct rpc_rqst *req = task->tk_rqstp;
1125 if (req->rq_received > 0 && !req->rq_bytes_sent)
1126 task->tk_status = req->rq_received;
1128 dprint_status(task);
1130 status = task->tk_status;
1132 task->tk_action = call_decode;
1136 task->tk_status = 0;
1142 * Delay any retries for 3 seconds, then handle as if it
1145 rpc_delay(task, 3*HZ);
1147 task->tk_action = call_timeout;
1148 if (task->tk_client->cl_discrtry)
1149 xprt_force_disconnect(task->tk_xprt);
1153 rpc_force_rebind(clnt);
1154 task->tk_action = call_bind;
1157 task->tk_action = call_transmit;
1160 /* shutdown or soft timeout */
1161 rpc_exit(task, status);
1164 printk("%s: RPC call returned error %d\n",
1165 clnt->cl_protname, -status);
1166 rpc_exit(task, status);
1171 * 6a. Handle RPC timeout
1172 * We do not release the request slot, so we keep using the
1173 * same XID for all retransmits.
1176 call_timeout(struct rpc_task *task)
1178 struct rpc_clnt *clnt = task->tk_client;
1180 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1181 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1185 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1186 task->tk_timeouts++;
1188 if (RPC_IS_SOFT(task)) {
1189 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1190 clnt->cl_protname, clnt->cl_server);
1191 rpc_exit(task, -EIO);
1195 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1196 task->tk_flags |= RPC_CALL_MAJORSEEN;
1197 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1198 clnt->cl_protname, clnt->cl_server);
1200 rpc_force_rebind(clnt);
1203 clnt->cl_stats->rpcretrans++;
1204 task->tk_action = call_bind;
1205 task->tk_status = 0;
1209 * 7. Decode the RPC reply
1212 call_decode(struct rpc_task *task)
1214 struct rpc_clnt *clnt = task->tk_client;
1215 struct rpc_rqst *req = task->tk_rqstp;
1216 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1219 dprintk("RPC: %5u call_decode (status %d)\n",
1220 task->tk_pid, task->tk_status);
1222 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1223 printk(KERN_NOTICE "%s: server %s OK\n",
1224 clnt->cl_protname, clnt->cl_server);
1225 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1228 if (task->tk_status < 12) {
1229 if (!RPC_IS_SOFT(task)) {
1230 task->tk_action = call_bind;
1231 clnt->cl_stats->rpcretrans++;
1234 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1235 clnt->cl_protname, task->tk_status);
1236 task->tk_action = call_timeout;
1241 * Ensure that we see all writes made by xprt_complete_rqst()
1242 * before it changed req->rq_received.
1245 req->rq_rcv_buf.len = req->rq_private_buf.len;
1247 /* Check that the softirq receive buffer is valid */
1248 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1249 sizeof(req->rq_rcv_buf)) != 0);
1251 /* Verify the RPC header */
1252 p = call_verify(task);
1254 if (p == ERR_PTR(-EAGAIN))
1259 task->tk_action = rpc_exit_task;
1262 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1263 task->tk_msg.rpc_resp);
1265 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1269 req->rq_received = req->rq_private_buf.len = 0;
1270 task->tk_status = 0;
1271 if (task->tk_client->cl_discrtry)
1272 xprt_force_disconnect(task->tk_xprt);
1276 * 8. Refresh the credentials if rejected by the server
1279 call_refresh(struct rpc_task *task)
1281 dprint_status(task);
1283 task->tk_action = call_refreshresult;
1284 task->tk_status = 0;
1285 task->tk_client->cl_stats->rpcauthrefresh++;
1286 rpcauth_refreshcred(task);
1290 * 8a. Process the results of a credential refresh
1293 call_refreshresult(struct rpc_task *task)
1295 int status = task->tk_status;
1297 dprint_status(task);
1299 task->tk_status = 0;
1300 task->tk_action = call_reserve;
1301 if (status >= 0 && rpcauth_uptodatecred(task))
1303 if (status == -EACCES) {
1304 rpc_exit(task, -EACCES);
1307 task->tk_action = call_refresh;
1308 if (status != -ETIMEDOUT)
1309 rpc_delay(task, 3*HZ);
1314 * Call header serialization
1317 call_header(struct rpc_task *task)
1319 struct rpc_clnt *clnt = task->tk_client;
1320 struct rpc_rqst *req = task->tk_rqstp;
1321 __be32 *p = req->rq_svec[0].iov_base;
1323 /* FIXME: check buffer size? */
1325 p = xprt_skip_transport_header(task->tk_xprt, p);
1326 *p++ = req->rq_xid; /* XID */
1327 *p++ = htonl(RPC_CALL); /* CALL */
1328 *p++ = htonl(RPC_VERSION); /* RPC version */
1329 *p++ = htonl(clnt->cl_prog); /* program number */
1330 *p++ = htonl(clnt->cl_vers); /* program version */
1331 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1332 p = rpcauth_marshcred(task, p);
1333 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1338 * Reply header verification
1341 call_verify(struct rpc_task *task)
1343 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1344 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1345 __be32 *p = iov->iov_base;
1347 int error = -EACCES;
1349 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1350 /* RFC-1014 says that the representation of XDR data must be a
1351 * multiple of four bytes
1352 * - if it isn't pointer subtraction in the NFS client may give
1355 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1356 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1357 task->tk_rqstp->rq_rcv_buf.len);
1362 p += 1; /* skip XID */
1364 if ((n = ntohl(*p++)) != RPC_REPLY) {
1365 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1366 task->tk_pid, __FUNCTION__, n);
1369 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1372 switch ((n = ntohl(*p++))) {
1373 case RPC_AUTH_ERROR:
1376 dprintk("RPC: %5u %s: RPC call version "
1378 task->tk_pid, __FUNCTION__);
1379 error = -EPROTONOSUPPORT;
1382 dprintk("RPC: %5u %s: RPC call rejected, "
1383 "unknown error: %x\n",
1384 task->tk_pid, __FUNCTION__, n);
1389 switch ((n = ntohl(*p++))) {
1390 case RPC_AUTH_REJECTEDCRED:
1391 case RPC_AUTH_REJECTEDVERF:
1392 case RPCSEC_GSS_CREDPROBLEM:
1393 case RPCSEC_GSS_CTXPROBLEM:
1394 if (!task->tk_cred_retry)
1396 task->tk_cred_retry--;
1397 dprintk("RPC: %5u %s: retry stale creds\n",
1398 task->tk_pid, __FUNCTION__);
1399 rpcauth_invalcred(task);
1400 /* Ensure we obtain a new XID! */
1402 task->tk_action = call_refresh;
1404 case RPC_AUTH_BADCRED:
1405 case RPC_AUTH_BADVERF:
1406 /* possibly garbled cred/verf? */
1407 if (!task->tk_garb_retry)
1409 task->tk_garb_retry--;
1410 dprintk("RPC: %5u %s: retry garbled creds\n",
1411 task->tk_pid, __FUNCTION__);
1412 task->tk_action = call_bind;
1414 case RPC_AUTH_TOOWEAK:
1415 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1416 "authentication.\n", task->tk_client->cl_server);
1419 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1420 task->tk_pid, __FUNCTION__, n);
1423 dprintk("RPC: %5u %s: call rejected %d\n",
1424 task->tk_pid, __FUNCTION__, n);
1427 if (!(p = rpcauth_checkverf(task, p))) {
1428 dprintk("RPC: %5u %s: auth check failed\n",
1429 task->tk_pid, __FUNCTION__);
1430 goto out_garbage; /* bad verifier, retry */
1432 len = p - (__be32 *)iov->iov_base - 1;
1435 switch ((n = ntohl(*p++))) {
1438 case RPC_PROG_UNAVAIL:
1439 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1440 task->tk_pid, __FUNCTION__,
1441 (unsigned int)task->tk_client->cl_prog,
1442 task->tk_client->cl_server);
1443 error = -EPFNOSUPPORT;
1445 case RPC_PROG_MISMATCH:
1446 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1447 "server %s\n", task->tk_pid, __FUNCTION__,
1448 (unsigned int)task->tk_client->cl_prog,
1449 (unsigned int)task->tk_client->cl_vers,
1450 task->tk_client->cl_server);
1451 error = -EPROTONOSUPPORT;
1453 case RPC_PROC_UNAVAIL:
1454 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1455 "version %u on server %s\n",
1456 task->tk_pid, __FUNCTION__,
1457 task->tk_msg.rpc_proc,
1458 task->tk_client->cl_prog,
1459 task->tk_client->cl_vers,
1460 task->tk_client->cl_server);
1461 error = -EOPNOTSUPP;
1463 case RPC_GARBAGE_ARGS:
1464 dprintk("RPC: %5u %s: server saw garbage\n",
1465 task->tk_pid, __FUNCTION__);
1468 dprintk("RPC: %5u %s: server accept status: %x\n",
1469 task->tk_pid, __FUNCTION__, n);
1474 task->tk_client->cl_stats->rpcgarbage++;
1475 if (task->tk_garb_retry) {
1476 task->tk_garb_retry--;
1477 dprintk("RPC: %5u %s: retrying\n",
1478 task->tk_pid, __FUNCTION__);
1479 task->tk_action = call_bind;
1481 return ERR_PTR(-EAGAIN);
1486 rpc_exit(task, error);
1487 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1488 __FUNCTION__, error);
1489 return ERR_PTR(error);
1491 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1496 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1501 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1506 static struct rpc_procinfo rpcproc_null = {
1507 .p_encode = rpcproc_encode_null,
1508 .p_decode = rpcproc_decode_null,
1511 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1513 struct rpc_message msg = {
1514 .rpc_proc = &rpcproc_null,
1517 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1518 err = rpc_call_sync(clnt, &msg, flags);
1519 put_rpccred(msg.rpc_cred);
1523 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1525 struct rpc_message msg = {
1526 .rpc_proc = &rpcproc_null,
1529 struct rpc_task_setup task_setup_data = {
1531 .rpc_message = &msg,
1532 .callback_ops = &rpc_default_ops,
1535 return rpc_run_task(&task_setup_data);
1537 EXPORT_SYMBOL_GPL(rpc_call_null);
1540 void rpc_show_tasks(void)
1542 struct rpc_clnt *clnt;
1545 spin_lock(&rpc_client_lock);
1546 if (list_empty(&all_clients))
1548 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1549 "-rpcwait -action- ---ops--\n");
1550 list_for_each_entry(clnt, &all_clients, cl_clients) {
1551 if (list_empty(&clnt->cl_tasks))
1553 spin_lock(&clnt->cl_lock);
1554 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1555 const char *rpc_waitq = "none";
1558 if (t->tk_msg.rpc_proc)
1559 proc = t->tk_msg.rpc_proc->p_proc;
1563 if (RPC_IS_QUEUED(t))
1564 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1566 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1568 t->tk_flags, t->tk_status,
1570 (t->tk_client ? t->tk_client->cl_prog : 0),
1571 t->tk_rqstp, t->tk_timeout,
1573 t->tk_action, t->tk_ops);
1575 spin_unlock(&clnt->cl_lock);
1578 spin_unlock(&rpc_client_lock);