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/vs_cvirt.h>
35 #include <linux/sunrpc/clnt.h>
36 #include <linux/sunrpc/rpc_pipe_fs.h>
37 #include <linux/sunrpc/metrics.h>
40 #define RPC_SLACK_SPACE (1024) /* total overkill */
43 # define RPCDBG_FACILITY RPCDBG_CALL
46 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
49 static void call_start(struct rpc_task *task);
50 static void call_reserve(struct rpc_task *task);
51 static void call_reserveresult(struct rpc_task *task);
52 static void call_allocate(struct rpc_task *task);
53 static void call_encode(struct rpc_task *task);
54 static void call_decode(struct rpc_task *task);
55 static void call_bind(struct rpc_task *task);
56 static void call_bind_status(struct rpc_task *task);
57 static void call_transmit(struct rpc_task *task);
58 static void call_status(struct rpc_task *task);
59 static void call_transmit_status(struct rpc_task *task);
60 static void call_refresh(struct rpc_task *task);
61 static void call_refreshresult(struct rpc_task *task);
62 static void call_timeout(struct rpc_task *task);
63 static void call_connect(struct rpc_task *task);
64 static void call_connect_status(struct rpc_task *task);
65 static __be32 * call_header(struct rpc_task *task);
66 static __be32 * call_verify(struct rpc_task *task);
70 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
72 static uint32_t clntid;
75 clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
76 clnt->cl_dentry = ERR_PTR(-ENOENT);
80 clnt->cl_vfsmnt = rpc_get_mount();
81 if (IS_ERR(clnt->cl_vfsmnt))
82 return PTR_ERR(clnt->cl_vfsmnt);
85 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
86 "%s/clnt%x", dir_name,
87 (unsigned int)clntid++);
88 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
89 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
90 if (!IS_ERR(clnt->cl_dentry))
92 error = PTR_ERR(clnt->cl_dentry);
93 if (error != -EEXIST) {
94 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
95 clnt->cl_pathname, error);
102 static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor)
104 struct rpc_version *version;
105 struct rpc_clnt *clnt = NULL;
106 struct rpc_auth *auth;
110 dprintk("RPC: creating %s client for %s (xprt %p)\n",
111 program->name, servname, xprt);
116 if (vers >= program->nrvers || !(version = program->version[vers]))
120 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
123 atomic_set(&clnt->cl_users, 0);
124 atomic_set(&clnt->cl_count, 1);
125 clnt->cl_parent = clnt;
127 clnt->cl_server = clnt->cl_inline_name;
128 len = strlen(servname) + 1;
129 if (len > sizeof(clnt->cl_inline_name)) {
130 char *buf = kmalloc(len, GFP_KERNEL);
132 clnt->cl_server = buf;
134 len = sizeof(clnt->cl_inline_name);
136 strlcpy(clnt->cl_server, servname, len);
138 clnt->cl_xprt = xprt;
139 clnt->cl_procinfo = version->procs;
140 clnt->cl_maxproc = version->nrprocs;
141 clnt->cl_protname = program->name;
142 clnt->cl_prog = program->number;
143 clnt->cl_vers = version->number;
144 clnt->cl_stats = program->stats;
145 clnt->cl_metrics = rpc_alloc_iostats(clnt);
147 if (clnt->cl_metrics == NULL)
149 clnt->cl_program = program;
151 if (!xprt_bound(clnt->cl_xprt))
152 clnt->cl_autobind = 1;
154 clnt->cl_rtt = &clnt->cl_rtt_default;
155 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
157 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
161 auth = rpcauth_create(flavor, clnt);
163 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
169 /* save the nodename */
170 clnt->cl_nodelen = strlen(utsname()->nodename);
171 if (clnt->cl_nodelen > UNX_MAXNODENAME)
172 clnt->cl_nodelen = UNX_MAXNODENAME;
173 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
177 if (!IS_ERR(clnt->cl_dentry)) {
178 rpc_rmdir(clnt->cl_dentry);
182 rpc_free_iostats(clnt->cl_metrics);
184 if (clnt->cl_server != clnt->cl_inline_name)
185 kfree(clnt->cl_server);
194 * rpc_create - create an RPC client and transport with one call
195 * @args: rpc_clnt create argument structure
197 * Creates and initializes an RPC transport and an RPC client.
199 * It can ping the server in order to determine if it is up, and to see if
200 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
201 * this behavior so asynchronous tasks can also use rpc_create.
203 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
205 struct rpc_xprt *xprt;
206 struct rpc_clnt *clnt;
208 xprt = xprt_create_transport(args->protocol, args->address,
209 args->addrsize, args->timeout);
211 return (struct rpc_clnt *)xprt;
214 * By default, kernel RPC client connects from a reserved port.
215 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
216 * but it is always enabled for rpciod, which handles the connect
220 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
223 dprintk("RPC: creating %s client for %s (xprt %p)\n",
224 args->program->name, args->servername, xprt);
226 clnt = rpc_new_client(xprt, args->servername, args->program,
227 args->version, args->authflavor);
231 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
232 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
234 rpc_shutdown_client(clnt);
239 clnt->cl_softrtry = 1;
240 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
241 clnt->cl_softrtry = 0;
243 if (args->flags & RPC_CLNT_CREATE_INTR)
245 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
246 clnt->cl_autobind = 1;
247 if (args->flags & RPC_CLNT_CREATE_ONESHOT)
248 clnt->cl_oneshot = 1;
249 /* TODO: handle RPC_CLNT_CREATE_TAGGED
250 if (args->flags & RPC_CLNT_CREATE_TAGGED)
254 EXPORT_SYMBOL_GPL(rpc_create);
257 * This function clones the RPC client structure. It allows us to share the
258 * same transport while varying parameters such as the authentication
262 rpc_clone_client(struct rpc_clnt *clnt)
264 struct rpc_clnt *new;
267 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
270 atomic_set(&new->cl_count, 1);
271 atomic_set(&new->cl_users, 0);
272 new->cl_metrics = rpc_alloc_iostats(clnt);
273 if (new->cl_metrics == NULL)
275 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
278 new->cl_parent = clnt;
279 atomic_inc(&clnt->cl_count);
280 new->cl_xprt = xprt_get(clnt->cl_xprt);
281 /* Turn off autobind on clones */
282 new->cl_autobind = 0;
285 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
287 atomic_inc(&new->cl_auth->au_count);
290 rpc_free_iostats(new->cl_metrics);
294 dprintk("RPC: %s returned error %d\n", __FUNCTION__, err);
299 * Properly shut down an RPC client, terminating all outstanding
300 * requests. Note that we must be certain that cl_oneshot and
301 * cl_dead are cleared, or else the client would be destroyed
302 * when the last task releases it.
305 rpc_shutdown_client(struct rpc_clnt *clnt)
307 dprintk("RPC: shutting down %s client for %s, tasks=%d\n",
308 clnt->cl_protname, clnt->cl_server,
309 atomic_read(&clnt->cl_users));
311 while (atomic_read(&clnt->cl_users) > 0) {
312 /* Don't let rpc_release_client destroy us */
313 clnt->cl_oneshot = 0;
315 rpc_killall_tasks(clnt);
316 wait_event_timeout(destroy_wait,
317 !atomic_read(&clnt->cl_users), 1*HZ);
320 if (atomic_read(&clnt->cl_users) < 0) {
321 printk(KERN_ERR "RPC: rpc_shutdown_client clnt %p tasks=%d\n",
322 clnt, atomic_read(&clnt->cl_users));
329 return rpc_destroy_client(clnt);
333 * Delete an RPC client
336 rpc_destroy_client(struct rpc_clnt *clnt)
338 if (!atomic_dec_and_test(&clnt->cl_count))
340 BUG_ON(atomic_read(&clnt->cl_users) != 0);
342 dprintk("RPC: destroying %s client for %s\n",
343 clnt->cl_protname, clnt->cl_server);
345 rpcauth_destroy(clnt->cl_auth);
346 clnt->cl_auth = NULL;
348 if (!IS_ERR(clnt->cl_dentry)) {
349 rpc_rmdir(clnt->cl_dentry);
352 if (clnt->cl_parent != clnt) {
353 rpc_destroy_client(clnt->cl_parent);
356 if (clnt->cl_server != clnt->cl_inline_name)
357 kfree(clnt->cl_server);
359 rpc_free_iostats(clnt->cl_metrics);
360 clnt->cl_metrics = NULL;
361 xprt_put(clnt->cl_xprt);
367 * Release an RPC client
370 rpc_release_client(struct rpc_clnt *clnt)
372 dprintk("RPC: rpc_release_client(%p, %d)\n",
373 clnt, atomic_read(&clnt->cl_users));
375 if (!atomic_dec_and_test(&clnt->cl_users))
377 wake_up(&destroy_wait);
378 if (clnt->cl_oneshot || clnt->cl_dead)
379 rpc_destroy_client(clnt);
383 * rpc_bind_new_program - bind a new RPC program to an existing client
384 * @old - old rpc_client
385 * @program - rpc program to set
386 * @vers - rpc program version
388 * Clones the rpc client and sets up a new RPC program. This is mainly
389 * of use for enabling different RPC programs to share the same transport.
390 * The Sun NFSv2/v3 ACL protocol can do this.
392 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
393 struct rpc_program *program,
396 struct rpc_clnt *clnt;
397 struct rpc_version *version;
400 BUG_ON(vers >= program->nrvers || !program->version[vers]);
401 version = program->version[vers];
402 clnt = rpc_clone_client(old);
405 clnt->cl_procinfo = version->procs;
406 clnt->cl_maxproc = version->nrprocs;
407 clnt->cl_protname = program->name;
408 clnt->cl_prog = program->number;
409 clnt->cl_vers = version->number;
410 clnt->cl_stats = program->stats;
411 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
413 rpc_shutdown_client(clnt);
421 * Default callback for async RPC calls
424 rpc_default_callback(struct rpc_task *task, void *data)
428 static const struct rpc_call_ops rpc_default_ops = {
429 .rpc_call_done = rpc_default_callback,
433 * Export the signal mask handling for synchronous code that
434 * sleeps on RPC calls
436 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
438 static void rpc_save_sigmask(sigset_t *oldset, int intr)
440 unsigned long sigallow = sigmask(SIGKILL);
443 /* Block all signals except those listed in sigallow */
445 sigallow |= RPC_INTR_SIGNALS;
446 siginitsetinv(&sigmask, sigallow);
447 sigprocmask(SIG_BLOCK, &sigmask, oldset);
450 static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
452 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
455 static inline void rpc_restore_sigmask(sigset_t *oldset)
457 sigprocmask(SIG_SETMASK, oldset, NULL);
460 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
462 rpc_save_sigmask(oldset, clnt->cl_intr);
465 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
467 rpc_restore_sigmask(oldset);
471 * New rpc_call implementation
473 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
475 struct rpc_task *task;
479 /* If this client is slain all further I/O fails */
483 BUG_ON(flags & RPC_TASK_ASYNC);
485 task = rpc_new_task(clnt, flags, &rpc_default_ops, NULL);
489 /* Mask signals on RPC calls _and_ GSS_AUTH upcalls */
490 rpc_task_sigmask(task, &oldset);
492 rpc_call_setup(task, msg, 0);
494 /* Set up the call info struct and execute the task */
495 status = task->tk_status;
498 atomic_inc(&task->tk_count);
499 status = rpc_execute(task);
501 status = task->tk_status;
504 rpc_restore_sigmask(&oldset);
509 * New rpc_call implementation
512 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
513 const struct rpc_call_ops *tk_ops, void *data)
515 struct rpc_task *task;
519 /* If this client is slain all further I/O fails */
524 flags |= RPC_TASK_ASYNC;
526 /* Create/initialize a new RPC task */
528 if (!(task = rpc_new_task(clnt, flags, tk_ops, data)))
531 /* Mask signals on GSS_AUTH upcalls */
532 rpc_task_sigmask(task, &oldset);
534 rpc_call_setup(task, msg, 0);
536 /* Set up the call info struct and execute the task */
537 status = task->tk_status;
543 rpc_restore_sigmask(&oldset);
546 rpc_release_calldata(tk_ops, data);
552 rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
555 task->tk_flags |= flags;
556 /* Bind the user cred */
557 if (task->tk_msg.rpc_cred != NULL)
558 rpcauth_holdcred(task);
560 rpcauth_bindcred(task);
562 if (task->tk_status == 0)
563 task->tk_action = call_start;
565 task->tk_action = rpc_exit_task;
569 * rpc_peeraddr - extract remote peer address from clnt's xprt
570 * @clnt: RPC client structure
571 * @buf: target buffer
572 * @size: length of target buffer
574 * Returns the number of bytes that are actually in the stored address.
576 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
579 struct rpc_xprt *xprt = clnt->cl_xprt;
581 bytes = sizeof(xprt->addr);
584 memcpy(buf, &clnt->cl_xprt->addr, bytes);
585 return xprt->addrlen;
587 EXPORT_SYMBOL_GPL(rpc_peeraddr);
590 * rpc_peeraddr2str - return remote peer address in printable format
591 * @clnt: RPC client structure
592 * @format: address format
595 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
597 struct rpc_xprt *xprt = clnt->cl_xprt;
599 if (xprt->address_strings[format] != NULL)
600 return xprt->address_strings[format];
602 return "unprintable";
604 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
607 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
609 struct rpc_xprt *xprt = clnt->cl_xprt;
610 if (xprt->ops->set_buffer_size)
611 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
615 * Return size of largest payload RPC client can support, in bytes
617 * For stream transports, this is one RPC record fragment (see RFC
618 * 1831), as we don't support multi-record requests yet. For datagram
619 * transports, this is the size of an IP packet minus the IP, UDP, and
622 size_t rpc_max_payload(struct rpc_clnt *clnt)
624 return clnt->cl_xprt->max_payload;
626 EXPORT_SYMBOL_GPL(rpc_max_payload);
629 * rpc_force_rebind - force transport to check that remote port is unchanged
630 * @clnt: client to rebind
633 void rpc_force_rebind(struct rpc_clnt *clnt)
635 if (clnt->cl_autobind)
636 xprt_clear_bound(clnt->cl_xprt);
638 EXPORT_SYMBOL_GPL(rpc_force_rebind);
641 * Restart an (async) RPC call. Usually called from within the
645 rpc_restart_call(struct rpc_task *task)
647 if (RPC_ASSASSINATED(task))
650 task->tk_action = call_start;
656 * Other FSM states can be visited zero or more times, but
657 * this state is visited exactly once for each RPC.
660 call_start(struct rpc_task *task)
662 struct rpc_clnt *clnt = task->tk_client;
664 dprintk("RPC: %4d call_start %s%d proc %d (%s)\n", task->tk_pid,
665 clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc,
666 (RPC_IS_ASYNC(task) ? "async" : "sync"));
668 /* Increment call count */
669 task->tk_msg.rpc_proc->p_count++;
670 clnt->cl_stats->rpccnt++;
671 task->tk_action = call_reserve;
675 * 1. Reserve an RPC call slot
678 call_reserve(struct rpc_task *task)
680 dprintk("RPC: %4d call_reserve\n", task->tk_pid);
682 if (!rpcauth_uptodatecred(task)) {
683 task->tk_action = call_refresh;
688 task->tk_action = call_reserveresult;
693 * 1b. Grok the result of xprt_reserve()
696 call_reserveresult(struct rpc_task *task)
698 int status = task->tk_status;
700 dprintk("RPC: %4d call_reserveresult (status %d)\n",
701 task->tk_pid, task->tk_status);
704 * After a call to xprt_reserve(), we must have either
705 * a request slot or else an error status.
709 if (task->tk_rqstp) {
710 task->tk_action = call_allocate;
714 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
715 __FUNCTION__, status);
716 rpc_exit(task, -EIO);
721 * Even though there was an error, we may have acquired
722 * a request slot somehow. Make sure not to leak it.
724 if (task->tk_rqstp) {
725 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
726 __FUNCTION__, status);
731 case -EAGAIN: /* woken up; retry */
732 task->tk_action = call_reserve;
734 case -EIO: /* probably a shutdown */
737 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
738 __FUNCTION__, status);
741 rpc_exit(task, status);
745 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
746 * (Note: buffer memory is freed in xprt_release).
749 call_allocate(struct rpc_task *task)
751 struct rpc_rqst *req = task->tk_rqstp;
752 struct rpc_xprt *xprt = task->tk_xprt;
755 dprintk("RPC: %4d call_allocate (status %d)\n",
756 task->tk_pid, task->tk_status);
757 task->tk_action = call_bind;
761 /* FIXME: compute buffer requirements more exactly using
763 bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE;
765 if (xprt->ops->buf_alloc(task, bufsiz << 1) != NULL)
767 printk(KERN_INFO "RPC: buffer allocation failed for task %p\n", task);
769 if (RPC_IS_ASYNC(task) || !signalled()) {
771 task->tk_action = call_reserve;
772 rpc_delay(task, HZ>>4);
776 rpc_exit(task, -ERESTARTSYS);
780 rpc_task_need_encode(struct rpc_task *task)
782 return task->tk_rqstp->rq_snd_buf.len == 0;
786 rpc_task_force_reencode(struct rpc_task *task)
788 task->tk_rqstp->rq_snd_buf.len = 0;
792 * 3. Encode arguments of an RPC call
795 call_encode(struct rpc_task *task)
797 struct rpc_rqst *req = task->tk_rqstp;
798 struct xdr_buf *sndbuf = &req->rq_snd_buf;
799 struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
804 dprintk("RPC: %4d call_encode (status %d)\n",
805 task->tk_pid, task->tk_status);
807 /* Default buffer setup */
808 bufsiz = req->rq_bufsize >> 1;
809 sndbuf->head[0].iov_base = (void *)req->rq_buffer;
810 sndbuf->head[0].iov_len = bufsiz;
811 sndbuf->tail[0].iov_len = 0;
812 sndbuf->page_len = 0;
814 sndbuf->buflen = bufsiz;
815 rcvbuf->head[0].iov_base = (void *)((char *)req->rq_buffer + bufsiz);
816 rcvbuf->head[0].iov_len = bufsiz;
817 rcvbuf->tail[0].iov_len = 0;
818 rcvbuf->page_len = 0;
820 rcvbuf->buflen = bufsiz;
822 /* Encode header and provided arguments */
823 encode = task->tk_msg.rpc_proc->p_encode;
824 if (!(p = call_header(task))) {
825 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
826 rpc_exit(task, -EIO);
833 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
834 task->tk_msg.rpc_argp);
836 if (task->tk_status == -ENOMEM) {
837 /* XXX: Is this sane? */
838 rpc_delay(task, 3*HZ);
839 task->tk_status = -EAGAIN;
844 * 4. Get the server port number if not yet set
847 call_bind(struct rpc_task *task)
849 struct rpc_xprt *xprt = task->tk_xprt;
851 dprintk("RPC: %4d call_bind (status %d)\n",
852 task->tk_pid, task->tk_status);
854 task->tk_action = call_connect;
855 if (!xprt_bound(xprt)) {
856 task->tk_action = call_bind_status;
857 task->tk_timeout = xprt->bind_timeout;
858 xprt->ops->rpcbind(task);
863 * 4a. Sort out bind result
866 call_bind_status(struct rpc_task *task)
868 int status = -EACCES;
870 if (task->tk_status >= 0) {
871 dprintk("RPC: %4d call_bind_status (status %d)\n",
872 task->tk_pid, task->tk_status);
874 task->tk_action = call_connect;
878 switch (task->tk_status) {
880 dprintk("RPC: %4d remote rpcbind: RPC program/version unavailable\n",
882 rpc_delay(task, 3*HZ);
885 dprintk("RPC: %4d rpcbind request timed out\n",
889 dprintk("RPC: %4d remote rpcbind service unavailable\n",
892 case -EPROTONOSUPPORT:
893 dprintk("RPC: %4d remote rpcbind version 2 unavailable\n",
897 dprintk("RPC: %4d unrecognized rpcbind error (%d)\n",
898 task->tk_pid, -task->tk_status);
902 rpc_exit(task, status);
906 task->tk_action = call_timeout;
910 * 4b. Connect to the RPC server
913 call_connect(struct rpc_task *task)
915 struct rpc_xprt *xprt = task->tk_xprt;
917 dprintk("RPC: %4d call_connect xprt %p %s connected\n",
919 (xprt_connected(xprt) ? "is" : "is not"));
921 task->tk_action = call_transmit;
922 if (!xprt_connected(xprt)) {
923 task->tk_action = call_connect_status;
924 if (task->tk_status < 0)
931 * 4c. Sort out connect result
934 call_connect_status(struct rpc_task *task)
936 struct rpc_clnt *clnt = task->tk_client;
937 int status = task->tk_status;
939 dprintk("RPC: %5u call_connect_status (status %d)\n",
940 task->tk_pid, task->tk_status);
944 clnt->cl_stats->netreconn++;
945 task->tk_action = call_transmit;
949 /* Something failed: remote service port may have changed */
950 rpc_force_rebind(clnt);
955 task->tk_action = call_bind;
956 if (!RPC_IS_SOFT(task))
958 /* if soft mounted, test if we've timed out */
960 task->tk_action = call_timeout;
963 rpc_exit(task, -EIO);
967 * 5. Transmit the RPC request, and wait for reply
970 call_transmit(struct rpc_task *task)
972 dprintk("RPC: %4d call_transmit (status %d)\n",
973 task->tk_pid, task->tk_status);
975 task->tk_action = call_status;
976 if (task->tk_status < 0)
978 task->tk_status = xprt_prepare_transmit(task);
979 if (task->tk_status != 0)
981 task->tk_action = call_transmit_status;
982 /* Encode here so that rpcsec_gss can use correct sequence number. */
983 if (rpc_task_need_encode(task)) {
984 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
986 /* Did the encode result in an error condition? */
987 if (task->tk_status != 0)
991 if (task->tk_status < 0)
994 * On success, ensure that we call xprt_end_transmit() before sleeping
995 * in order to allow access to the socket to other RPC requests.
997 call_transmit_status(task);
998 if (task->tk_msg.rpc_proc->p_decode != NULL)
1000 task->tk_action = rpc_exit_task;
1001 rpc_wake_up_task(task);
1005 * 5a. Handle cleanup after a transmission
1008 call_transmit_status(struct rpc_task *task)
1010 task->tk_action = call_status;
1012 * Special case: if we've been waiting on the socket's write_space()
1013 * callback, then don't call xprt_end_transmit().
1015 if (task->tk_status == -EAGAIN)
1017 xprt_end_transmit(task);
1018 rpc_task_force_reencode(task);
1022 * 6. Sort out the RPC call status
1025 call_status(struct rpc_task *task)
1027 struct rpc_clnt *clnt = task->tk_client;
1028 struct rpc_rqst *req = task->tk_rqstp;
1031 if (req->rq_received > 0 && !req->rq_bytes_sent)
1032 task->tk_status = req->rq_received;
1034 dprintk("RPC: %4d call_status (status %d)\n",
1035 task->tk_pid, task->tk_status);
1037 status = task->tk_status;
1039 task->tk_action = call_decode;
1043 task->tk_status = 0;
1049 * Delay any retries for 3 seconds, then handle as if it
1052 rpc_delay(task, 3*HZ);
1054 task->tk_action = call_timeout;
1058 rpc_force_rebind(clnt);
1059 task->tk_action = call_bind;
1062 task->tk_action = call_transmit;
1065 /* shutdown or soft timeout */
1066 rpc_exit(task, status);
1069 printk("%s: RPC call returned error %d\n",
1070 clnt->cl_protname, -status);
1071 rpc_exit(task, status);
1076 * 6a. Handle RPC timeout
1077 * We do not release the request slot, so we keep using the
1078 * same XID for all retransmits.
1081 call_timeout(struct rpc_task *task)
1083 struct rpc_clnt *clnt = task->tk_client;
1085 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1086 dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid);
1090 dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid);
1091 task->tk_timeouts++;
1093 if (RPC_IS_SOFT(task)) {
1094 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1095 clnt->cl_protname, clnt->cl_server);
1096 rpc_exit(task, -EIO);
1100 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1101 task->tk_flags |= RPC_CALL_MAJORSEEN;
1102 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1103 clnt->cl_protname, clnt->cl_server);
1105 rpc_force_rebind(clnt);
1108 clnt->cl_stats->rpcretrans++;
1109 task->tk_action = call_bind;
1110 task->tk_status = 0;
1114 * 7. Decode the RPC reply
1117 call_decode(struct rpc_task *task)
1119 struct rpc_clnt *clnt = task->tk_client;
1120 struct rpc_rqst *req = task->tk_rqstp;
1121 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1124 dprintk("RPC: %4d call_decode (status %d)\n",
1125 task->tk_pid, task->tk_status);
1127 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1128 printk(KERN_NOTICE "%s: server %s OK\n",
1129 clnt->cl_protname, clnt->cl_server);
1130 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1133 if (task->tk_status < 12) {
1134 if (!RPC_IS_SOFT(task)) {
1135 task->tk_action = call_bind;
1136 clnt->cl_stats->rpcretrans++;
1139 dprintk("%s: too small RPC reply size (%d bytes)\n",
1140 clnt->cl_protname, task->tk_status);
1141 task->tk_action = call_timeout;
1146 * Ensure that we see all writes made by xprt_complete_rqst()
1147 * before it changed req->rq_received.
1150 req->rq_rcv_buf.len = req->rq_private_buf.len;
1152 /* Check that the softirq receive buffer is valid */
1153 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1154 sizeof(req->rq_rcv_buf)) != 0);
1156 /* Verify the RPC header */
1157 p = call_verify(task);
1159 if (p == ERR_PTR(-EAGAIN))
1164 task->tk_action = rpc_exit_task;
1168 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1169 task->tk_msg.rpc_resp);
1172 dprintk("RPC: %4d call_decode result %d\n", task->tk_pid,
1176 req->rq_received = req->rq_private_buf.len = 0;
1177 task->tk_status = 0;
1181 * 8. Refresh the credentials if rejected by the server
1184 call_refresh(struct rpc_task *task)
1186 dprintk("RPC: %4d call_refresh\n", task->tk_pid);
1188 xprt_release(task); /* Must do to obtain new XID */
1189 task->tk_action = call_refreshresult;
1190 task->tk_status = 0;
1191 task->tk_client->cl_stats->rpcauthrefresh++;
1192 rpcauth_refreshcred(task);
1196 * 8a. Process the results of a credential refresh
1199 call_refreshresult(struct rpc_task *task)
1201 int status = task->tk_status;
1202 dprintk("RPC: %4d call_refreshresult (status %d)\n",
1203 task->tk_pid, task->tk_status);
1205 task->tk_status = 0;
1206 task->tk_action = call_reserve;
1207 if (status >= 0 && rpcauth_uptodatecred(task))
1209 if (status == -EACCES) {
1210 rpc_exit(task, -EACCES);
1213 task->tk_action = call_refresh;
1214 if (status != -ETIMEDOUT)
1215 rpc_delay(task, 3*HZ);
1220 * Call header serialization
1223 call_header(struct rpc_task *task)
1225 struct rpc_clnt *clnt = task->tk_client;
1226 struct rpc_rqst *req = task->tk_rqstp;
1227 __be32 *p = req->rq_svec[0].iov_base;
1229 /* FIXME: check buffer size? */
1231 p = xprt_skip_transport_header(task->tk_xprt, p);
1232 *p++ = req->rq_xid; /* XID */
1233 *p++ = htonl(RPC_CALL); /* CALL */
1234 *p++ = htonl(RPC_VERSION); /* RPC version */
1235 *p++ = htonl(clnt->cl_prog); /* program number */
1236 *p++ = htonl(clnt->cl_vers); /* program version */
1237 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1238 p = rpcauth_marshcred(task, p);
1239 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1244 * Reply header verification
1247 call_verify(struct rpc_task *task)
1249 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1250 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1251 __be32 *p = iov->iov_base;
1253 int error = -EACCES;
1255 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1256 /* RFC-1014 says that the representation of XDR data must be a
1257 * multiple of four bytes
1258 * - if it isn't pointer subtraction in the NFS client may give
1262 "call_verify: XDR representation not a multiple of"
1263 " 4 bytes: 0x%x\n", task->tk_rqstp->rq_rcv_buf.len);
1268 p += 1; /* skip XID */
1270 if ((n = ntohl(*p++)) != RPC_REPLY) {
1271 printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n);
1274 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1277 switch ((n = ntohl(*p++))) {
1278 case RPC_AUTH_ERROR:
1281 dprintk("%s: RPC call version mismatch!\n", __FUNCTION__);
1282 error = -EPROTONOSUPPORT;
1285 dprintk("%s: RPC call rejected, unknown error: %x\n", __FUNCTION__, n);
1290 switch ((n = ntohl(*p++))) {
1291 case RPC_AUTH_REJECTEDCRED:
1292 case RPC_AUTH_REJECTEDVERF:
1293 case RPCSEC_GSS_CREDPROBLEM:
1294 case RPCSEC_GSS_CTXPROBLEM:
1295 if (!task->tk_cred_retry)
1297 task->tk_cred_retry--;
1298 dprintk("RPC: %4d call_verify: retry stale creds\n",
1300 rpcauth_invalcred(task);
1301 task->tk_action = call_refresh;
1303 case RPC_AUTH_BADCRED:
1304 case RPC_AUTH_BADVERF:
1305 /* possibly garbled cred/verf? */
1306 if (!task->tk_garb_retry)
1308 task->tk_garb_retry--;
1309 dprintk("RPC: %4d call_verify: retry garbled creds\n",
1311 task->tk_action = call_bind;
1313 case RPC_AUTH_TOOWEAK:
1314 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1315 "authentication.\n", task->tk_client->cl_server);
1318 printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n);
1321 dprintk("RPC: %4d call_verify: call rejected %d\n",
1325 if (!(p = rpcauth_checkverf(task, p))) {
1326 printk(KERN_WARNING "call_verify: auth check failed\n");
1327 goto out_garbage; /* bad verifier, retry */
1329 len = p - (__be32 *)iov->iov_base - 1;
1332 switch ((n = ntohl(*p++))) {
1335 case RPC_PROG_UNAVAIL:
1336 dprintk("RPC: call_verify: program %u is unsupported by server %s\n",
1337 (unsigned int)task->tk_client->cl_prog,
1338 task->tk_client->cl_server);
1339 error = -EPFNOSUPPORT;
1341 case RPC_PROG_MISMATCH:
1342 dprintk("RPC: call_verify: program %u, version %u unsupported by server %s\n",
1343 (unsigned int)task->tk_client->cl_prog,
1344 (unsigned int)task->tk_client->cl_vers,
1345 task->tk_client->cl_server);
1346 error = -EPROTONOSUPPORT;
1348 case RPC_PROC_UNAVAIL:
1349 dprintk("RPC: call_verify: proc %p unsupported by program %u, version %u on server %s\n",
1350 task->tk_msg.rpc_proc,
1351 task->tk_client->cl_prog,
1352 task->tk_client->cl_vers,
1353 task->tk_client->cl_server);
1354 error = -EOPNOTSUPP;
1356 case RPC_GARBAGE_ARGS:
1357 dprintk("RPC: %4d %s: server saw garbage\n", task->tk_pid, __FUNCTION__);
1360 printk(KERN_WARNING "call_verify: server accept status: %x\n", n);
1365 task->tk_client->cl_stats->rpcgarbage++;
1366 if (task->tk_garb_retry) {
1367 task->tk_garb_retry--;
1368 dprintk("RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid);
1369 task->tk_action = call_bind;
1371 return ERR_PTR(-EAGAIN);
1373 printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__);
1377 rpc_exit(task, error);
1378 return ERR_PTR(error);
1380 printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__);
1384 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1389 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1394 static struct rpc_procinfo rpcproc_null = {
1395 .p_encode = rpcproc_encode_null,
1396 .p_decode = rpcproc_decode_null,
1399 int rpc_ping(struct rpc_clnt *clnt, int flags)
1401 struct rpc_message msg = {
1402 .rpc_proc = &rpcproc_null,
1405 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1406 err = rpc_call_sync(clnt, &msg, flags);
1407 put_rpccred(msg.rpc_cred);