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(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor)
127 struct rpc_version *version;
128 struct rpc_clnt *clnt = NULL;
129 struct rpc_auth *auth;
133 /* sanity check the name before trying to print it */
135 len = strlen(servname);
136 if (len > RPC_MAXNETNAMELEN)
140 dprintk("RPC: creating %s client for %s (xprt %p)\n",
141 program->name, servname, xprt);
149 if (vers >= program->nrvers || !(version = program->version[vers]))
153 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
156 clnt->cl_parent = clnt;
158 clnt->cl_server = clnt->cl_inline_name;
159 if (len > sizeof(clnt->cl_inline_name)) {
160 char *buf = kmalloc(len, GFP_KERNEL);
162 clnt->cl_server = buf;
164 len = sizeof(clnt->cl_inline_name);
166 strlcpy(clnt->cl_server, servname, len);
168 clnt->cl_xprt = xprt;
169 clnt->cl_procinfo = version->procs;
170 clnt->cl_maxproc = version->nrprocs;
171 clnt->cl_protname = program->name;
172 clnt->cl_prog = program->number;
173 clnt->cl_vers = version->number;
174 clnt->cl_stats = program->stats;
175 clnt->cl_metrics = rpc_alloc_iostats(clnt);
177 if (clnt->cl_metrics == NULL)
179 clnt->cl_program = program;
180 INIT_LIST_HEAD(&clnt->cl_tasks);
181 spin_lock_init(&clnt->cl_lock);
183 if (!xprt_bound(clnt->cl_xprt))
184 clnt->cl_autobind = 1;
186 clnt->cl_rtt = &clnt->cl_rtt_default;
187 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
189 kref_init(&clnt->cl_kref);
191 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
195 auth = rpcauth_create(flavor, clnt);
197 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
203 /* save the nodename */
204 clnt->cl_nodelen = strlen(utsname()->nodename);
205 if (clnt->cl_nodelen > UNX_MAXNODENAME)
206 clnt->cl_nodelen = UNX_MAXNODENAME;
207 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
208 rpc_register_client(clnt);
212 if (!IS_ERR(clnt->cl_dentry)) {
213 rpc_rmdir(clnt->cl_dentry);
217 rpc_free_iostats(clnt->cl_metrics);
219 if (clnt->cl_server != clnt->cl_inline_name)
220 kfree(clnt->cl_server);
231 * rpc_create - create an RPC client and transport with one call
232 * @args: rpc_clnt create argument structure
234 * Creates and initializes an RPC transport and an RPC client.
236 * It can ping the server in order to determine if it is up, and to see if
237 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
238 * this behavior so asynchronous tasks can also use rpc_create.
240 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
242 struct rpc_xprt *xprt;
243 struct rpc_clnt *clnt;
244 struct xprt_create xprtargs = {
245 .ident = args->protocol,
246 .srcaddr = args->saddress,
247 .dstaddr = args->address,
248 .addrlen = args->addrsize,
249 .timeout = args->timeout
253 xprt = xprt_create_transport(&xprtargs);
255 return (struct rpc_clnt *)xprt;
258 * If the caller chooses not to specify a hostname, whip
259 * up a string representation of the passed-in address.
261 if (args->servername == NULL) {
262 servername[0] = '\0';
263 switch (args->address->sa_family) {
265 struct sockaddr_in *sin =
266 (struct sockaddr_in *)args->address;
267 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
268 NIPQUAD(sin->sin_addr.s_addr));
272 struct sockaddr_in6 *sin =
273 (struct sockaddr_in6 *)args->address;
274 snprintf(servername, sizeof(servername), NIP6_FMT,
275 NIP6(sin->sin6_addr));
279 /* caller wants default server name, but
280 * address family isn't recognized. */
281 return ERR_PTR(-EINVAL);
283 args->servername = servername;
286 xprt = xprt_create_transport(&xprtargs);
288 return (struct rpc_clnt *)xprt;
291 * By default, kernel RPC client connects from a reserved port.
292 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
293 * but it is always enabled for rpciod, which handles the connect
297 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
300 clnt = rpc_new_client(xprt, args->servername, args->program,
301 args->version, args->authflavor);
305 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
306 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
308 rpc_shutdown_client(clnt);
313 clnt->cl_softrtry = 1;
314 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
315 clnt->cl_softrtry = 0;
317 if (args->flags & RPC_CLNT_CREATE_INTR)
319 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
320 clnt->cl_autobind = 1;
321 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
322 clnt->cl_discrtry = 1;
326 EXPORT_SYMBOL_GPL(rpc_create);
329 * This function clones the RPC client structure. It allows us to share the
330 * same transport while varying parameters such as the authentication
334 rpc_clone_client(struct rpc_clnt *clnt)
336 struct rpc_clnt *new;
339 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
342 new->cl_parent = clnt;
343 /* Turn off autobind on clones */
344 new->cl_autobind = 0;
345 INIT_LIST_HEAD(&new->cl_tasks);
346 spin_lock_init(&new->cl_lock);
347 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
348 new->cl_metrics = rpc_alloc_iostats(clnt);
349 if (new->cl_metrics == NULL)
351 kref_init(&new->cl_kref);
352 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
356 atomic_inc(&new->cl_auth->au_count);
357 xprt_get(clnt->cl_xprt);
358 kref_get(&clnt->cl_kref);
359 rpc_register_client(new);
363 rpc_free_iostats(new->cl_metrics);
367 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
370 EXPORT_SYMBOL_GPL(rpc_clone_client);
373 * Properly shut down an RPC client, terminating all outstanding
376 void rpc_shutdown_client(struct rpc_clnt *clnt)
378 dprintk("RPC: shutting down %s client for %s\n",
379 clnt->cl_protname, clnt->cl_server);
381 while (!list_empty(&clnt->cl_tasks)) {
382 rpc_killall_tasks(clnt);
383 wait_event_timeout(destroy_wait,
384 list_empty(&clnt->cl_tasks), 1*HZ);
387 rpc_release_client(clnt);
389 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
395 rpc_free_client(struct kref *kref)
397 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
399 dprintk("RPC: destroying %s client for %s\n",
400 clnt->cl_protname, clnt->cl_server);
401 if (!IS_ERR(clnt->cl_dentry)) {
402 rpc_rmdir(clnt->cl_dentry);
405 if (clnt->cl_parent != clnt) {
406 rpc_release_client(clnt->cl_parent);
409 if (clnt->cl_server != clnt->cl_inline_name)
410 kfree(clnt->cl_server);
412 rpc_unregister_client(clnt);
413 rpc_free_iostats(clnt->cl_metrics);
414 clnt->cl_metrics = NULL;
415 xprt_put(clnt->cl_xprt);
424 rpc_free_auth(struct kref *kref)
426 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
428 if (clnt->cl_auth == NULL) {
429 rpc_free_client(kref);
434 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
435 * release remaining GSS contexts. This mechanism ensures
436 * that it can do so safely.
439 rpcauth_release(clnt->cl_auth);
440 clnt->cl_auth = NULL;
441 kref_put(kref, rpc_free_client);
445 * Release reference to the RPC client
448 rpc_release_client(struct rpc_clnt *clnt)
450 dprintk("RPC: rpc_release_client(%p)\n", clnt);
452 if (list_empty(&clnt->cl_tasks))
453 wake_up(&destroy_wait);
454 kref_put(&clnt->cl_kref, rpc_free_auth);
458 * rpc_bind_new_program - bind a new RPC program to an existing client
459 * @old - old rpc_client
460 * @program - rpc program to set
461 * @vers - rpc program version
463 * Clones the rpc client and sets up a new RPC program. This is mainly
464 * of use for enabling different RPC programs to share the same transport.
465 * The Sun NFSv2/v3 ACL protocol can do this.
467 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
468 struct rpc_program *program,
471 struct rpc_clnt *clnt;
472 struct rpc_version *version;
475 BUG_ON(vers >= program->nrvers || !program->version[vers]);
476 version = program->version[vers];
477 clnt = rpc_clone_client(old);
480 clnt->cl_procinfo = version->procs;
481 clnt->cl_maxproc = version->nrprocs;
482 clnt->cl_protname = program->name;
483 clnt->cl_prog = program->number;
484 clnt->cl_vers = version->number;
485 clnt->cl_stats = program->stats;
486 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
488 rpc_shutdown_client(clnt);
494 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
497 * Default callback for async RPC calls
500 rpc_default_callback(struct rpc_task *task, void *data)
504 static const struct rpc_call_ops rpc_default_ops = {
505 .rpc_call_done = rpc_default_callback,
509 * Export the signal mask handling for synchronous code that
510 * sleeps on RPC calls
512 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
514 static void rpc_save_sigmask(sigset_t *oldset, int intr)
516 unsigned long sigallow = sigmask(SIGKILL);
519 /* Block all signals except those listed in sigallow */
521 sigallow |= RPC_INTR_SIGNALS;
522 siginitsetinv(&sigmask, sigallow);
523 sigprocmask(SIG_BLOCK, &sigmask, oldset);
526 static void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
528 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
531 static void rpc_restore_sigmask(sigset_t *oldset)
533 sigprocmask(SIG_SETMASK, oldset, NULL);
536 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
538 rpc_save_sigmask(oldset, clnt->cl_intr);
540 EXPORT_SYMBOL_GPL(rpc_clnt_sigmask);
542 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
544 rpc_restore_sigmask(oldset);
546 EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask);
549 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
550 * @task_setup_data: pointer to task initialisation data
552 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
554 struct rpc_task *task, *ret;
557 task = rpc_new_task(task_setup_data);
559 rpc_release_calldata(task_setup_data->callback_ops,
560 task_setup_data->callback_data);
561 ret = ERR_PTR(-ENOMEM);
565 if (task->tk_status != 0) {
566 ret = ERR_PTR(task->tk_status);
570 atomic_inc(&task->tk_count);
571 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
572 rpc_task_sigmask(task, &oldset);
574 rpc_restore_sigmask(&oldset);
579 EXPORT_SYMBOL_GPL(rpc_run_task);
582 * rpc_call_sync - Perform a synchronous RPC call
583 * @clnt: pointer to RPC client
584 * @msg: RPC call parameters
585 * @flags: RPC call flags
587 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
589 struct rpc_task *task;
590 struct rpc_task_setup task_setup_data = {
593 .callback_ops = &rpc_default_ops,
598 BUG_ON(flags & RPC_TASK_ASYNC);
600 task = rpc_run_task(&task_setup_data);
602 return PTR_ERR(task);
603 status = task->tk_status;
607 EXPORT_SYMBOL_GPL(rpc_call_sync);
610 * rpc_call_async - Perform an asynchronous RPC call
611 * @clnt: pointer to RPC client
612 * @msg: RPC call parameters
613 * @flags: RPC call flags
615 * @data: user call data
618 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
619 const struct rpc_call_ops *tk_ops, void *data)
621 struct rpc_task *task;
622 struct rpc_task_setup task_setup_data = {
625 .callback_ops = tk_ops,
626 .callback_data = data,
627 .flags = flags|RPC_TASK_ASYNC,
630 task = rpc_run_task(&task_setup_data);
632 return PTR_ERR(task);
636 EXPORT_SYMBOL_GPL(rpc_call_async);
639 rpc_call_start(struct rpc_task *task)
641 task->tk_action = call_start;
643 EXPORT_SYMBOL_GPL(rpc_call_start);
646 * rpc_peeraddr - extract remote peer address from clnt's xprt
647 * @clnt: RPC client structure
648 * @buf: target buffer
649 * @size: length of target buffer
651 * Returns the number of bytes that are actually in the stored address.
653 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
656 struct rpc_xprt *xprt = clnt->cl_xprt;
658 bytes = sizeof(xprt->addr);
661 memcpy(buf, &clnt->cl_xprt->addr, bytes);
662 return xprt->addrlen;
664 EXPORT_SYMBOL_GPL(rpc_peeraddr);
667 * rpc_peeraddr2str - return remote peer address in printable format
668 * @clnt: RPC client structure
669 * @format: address format
672 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
674 struct rpc_xprt *xprt = clnt->cl_xprt;
676 if (xprt->address_strings[format] != NULL)
677 return xprt->address_strings[format];
679 return "unprintable";
681 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
684 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
686 struct rpc_xprt *xprt = clnt->cl_xprt;
687 if (xprt->ops->set_buffer_size)
688 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
690 EXPORT_SYMBOL_GPL(rpc_setbufsize);
693 * Return size of largest payload RPC client can support, in bytes
695 * For stream transports, this is one RPC record fragment (see RFC
696 * 1831), as we don't support multi-record requests yet. For datagram
697 * transports, this is the size of an IP packet minus the IP, UDP, and
700 size_t rpc_max_payload(struct rpc_clnt *clnt)
702 return clnt->cl_xprt->max_payload;
704 EXPORT_SYMBOL_GPL(rpc_max_payload);
707 * rpc_force_rebind - force transport to check that remote port is unchanged
708 * @clnt: client to rebind
711 void rpc_force_rebind(struct rpc_clnt *clnt)
713 if (clnt->cl_autobind)
714 xprt_clear_bound(clnt->cl_xprt);
716 EXPORT_SYMBOL_GPL(rpc_force_rebind);
719 * Restart an (async) RPC call. Usually called from within the
723 rpc_restart_call(struct rpc_task *task)
725 if (RPC_ASSASSINATED(task))
728 task->tk_action = call_start;
730 EXPORT_SYMBOL_GPL(rpc_restart_call);
735 * Other FSM states can be visited zero or more times, but
736 * this state is visited exactly once for each RPC.
739 call_start(struct rpc_task *task)
741 struct rpc_clnt *clnt = task->tk_client;
743 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
744 clnt->cl_protname, clnt->cl_vers,
745 task->tk_msg.rpc_proc->p_proc,
746 (RPC_IS_ASYNC(task) ? "async" : "sync"));
748 /* Increment call count */
749 task->tk_msg.rpc_proc->p_count++;
750 clnt->cl_stats->rpccnt++;
751 task->tk_action = call_reserve;
755 * 1. Reserve an RPC call slot
758 call_reserve(struct rpc_task *task)
762 if (!rpcauth_uptodatecred(task)) {
763 task->tk_action = call_refresh;
768 task->tk_action = call_reserveresult;
773 * 1b. Grok the result of xprt_reserve()
776 call_reserveresult(struct rpc_task *task)
778 int status = task->tk_status;
783 * After a call to xprt_reserve(), we must have either
784 * a request slot or else an error status.
788 if (task->tk_rqstp) {
789 task->tk_action = call_allocate;
793 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
794 __FUNCTION__, status);
795 rpc_exit(task, -EIO);
800 * Even though there was an error, we may have acquired
801 * a request slot somehow. Make sure not to leak it.
803 if (task->tk_rqstp) {
804 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
805 __FUNCTION__, status);
810 case -EAGAIN: /* woken up; retry */
811 task->tk_action = call_reserve;
813 case -EIO: /* probably a shutdown */
816 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
817 __FUNCTION__, status);
820 rpc_exit(task, status);
824 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
825 * (Note: buffer memory is freed in xprt_release).
828 call_allocate(struct rpc_task *task)
830 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
831 struct rpc_rqst *req = task->tk_rqstp;
832 struct rpc_xprt *xprt = task->tk_xprt;
833 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
838 task->tk_action = call_bind;
843 if (proc->p_proc != 0) {
844 BUG_ON(proc->p_arglen == 0);
845 if (proc->p_decode != NULL)
846 BUG_ON(proc->p_replen == 0);
850 * Calculate the size (in quads) of the RPC call
851 * and reply headers, and convert both values
854 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
855 req->rq_callsize <<= 2;
856 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
857 req->rq_rcvsize <<= 2;
859 req->rq_buffer = xprt->ops->buf_alloc(task,
860 req->rq_callsize + req->rq_rcvsize);
861 if (req->rq_buffer != NULL)
864 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
866 if (RPC_IS_ASYNC(task) || !signalled()) {
867 task->tk_action = call_allocate;
868 rpc_delay(task, HZ>>4);
872 rpc_exit(task, -ERESTARTSYS);
876 rpc_task_need_encode(struct rpc_task *task)
878 return task->tk_rqstp->rq_snd_buf.len == 0;
882 rpc_task_force_reencode(struct rpc_task *task)
884 task->tk_rqstp->rq_snd_buf.len = 0;
888 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
890 buf->head[0].iov_base = start;
891 buf->head[0].iov_len = len;
892 buf->tail[0].iov_len = 0;
900 * 3. Encode arguments of an RPC call
903 call_encode(struct rpc_task *task)
905 struct rpc_rqst *req = task->tk_rqstp;
911 rpc_xdr_buf_init(&req->rq_snd_buf,
914 rpc_xdr_buf_init(&req->rq_rcv_buf,
915 (char *)req->rq_buffer + req->rq_callsize,
918 /* Encode header and provided arguments */
919 encode = task->tk_msg.rpc_proc->p_encode;
920 if (!(p = call_header(task))) {
921 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
922 rpc_exit(task, -EIO);
928 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
929 task->tk_msg.rpc_argp);
930 if (task->tk_status == -ENOMEM) {
931 /* XXX: Is this sane? */
932 rpc_delay(task, 3*HZ);
933 task->tk_status = -EAGAIN;
938 * 4. Get the server port number if not yet set
941 call_bind(struct rpc_task *task)
943 struct rpc_xprt *xprt = task->tk_xprt;
947 task->tk_action = call_connect;
948 if (!xprt_bound(xprt)) {
949 task->tk_action = call_bind_status;
950 task->tk_timeout = xprt->bind_timeout;
951 xprt->ops->rpcbind(task);
956 * 4a. Sort out bind result
959 call_bind_status(struct rpc_task *task)
963 if (task->tk_status >= 0) {
966 task->tk_action = call_connect;
970 switch (task->tk_status) {
972 dprintk("RPC: %5u rpcbind waiting for another request "
973 "to finish\n", task->tk_pid);
974 /* avoid busy-waiting here -- could be a network outage. */
975 rpc_delay(task, 5*HZ);
978 dprintk("RPC: %5u remote rpcbind: RPC program/version "
979 "unavailable\n", task->tk_pid);
980 /* fail immediately if this is an RPC ping */
981 if (task->tk_msg.rpc_proc->p_proc == 0) {
982 status = -EOPNOTSUPP;
985 rpc_delay(task, 3*HZ);
988 dprintk("RPC: %5u rpcbind request timed out\n",
992 /* server doesn't support any rpcbind version we know of */
993 dprintk("RPC: %5u remote rpcbind service unavailable\n",
996 case -EPROTONOSUPPORT:
997 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1000 task->tk_action = call_bind;
1003 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1004 task->tk_pid, -task->tk_status);
1007 rpc_exit(task, status);
1011 task->tk_action = call_timeout;
1015 * 4b. Connect to the RPC server
1018 call_connect(struct rpc_task *task)
1020 struct rpc_xprt *xprt = task->tk_xprt;
1022 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1024 (xprt_connected(xprt) ? "is" : "is not"));
1026 task->tk_action = call_transmit;
1027 if (!xprt_connected(xprt)) {
1028 task->tk_action = call_connect_status;
1029 if (task->tk_status < 0)
1036 * 4c. Sort out connect result
1039 call_connect_status(struct rpc_task *task)
1041 struct rpc_clnt *clnt = task->tk_client;
1042 int status = task->tk_status;
1044 dprint_status(task);
1046 task->tk_status = 0;
1048 clnt->cl_stats->netreconn++;
1049 task->tk_action = call_transmit;
1053 /* Something failed: remote service port may have changed */
1054 rpc_force_rebind(clnt);
1059 task->tk_action = call_bind;
1060 if (!RPC_IS_SOFT(task))
1062 /* if soft mounted, test if we've timed out */
1064 task->tk_action = call_timeout;
1067 rpc_exit(task, -EIO);
1071 * 5. Transmit the RPC request, and wait for reply
1074 call_transmit(struct rpc_task *task)
1076 dprint_status(task);
1078 task->tk_action = call_status;
1079 if (task->tk_status < 0)
1081 task->tk_status = xprt_prepare_transmit(task);
1082 if (task->tk_status != 0)
1084 task->tk_action = call_transmit_status;
1085 /* Encode here so that rpcsec_gss can use correct sequence number. */
1086 if (rpc_task_need_encode(task)) {
1087 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1089 /* Did the encode result in an error condition? */
1090 if (task->tk_status != 0)
1093 xprt_transmit(task);
1094 if (task->tk_status < 0)
1097 * On success, ensure that we call xprt_end_transmit() before sleeping
1098 * in order to allow access to the socket to other RPC requests.
1100 call_transmit_status(task);
1101 if (task->tk_msg.rpc_proc->p_decode != NULL)
1103 task->tk_action = rpc_exit_task;
1104 rpc_wake_up_task(task);
1108 * 5a. Handle cleanup after a transmission
1111 call_transmit_status(struct rpc_task *task)
1113 task->tk_action = call_status;
1115 * Special case: if we've been waiting on the socket's write_space()
1116 * callback, then don't call xprt_end_transmit().
1118 if (task->tk_status == -EAGAIN)
1120 xprt_end_transmit(task);
1121 rpc_task_force_reencode(task);
1125 * 6. Sort out the RPC call status
1128 call_status(struct rpc_task *task)
1130 struct rpc_clnt *clnt = task->tk_client;
1131 struct rpc_rqst *req = task->tk_rqstp;
1134 if (req->rq_received > 0 && !req->rq_bytes_sent)
1135 task->tk_status = req->rq_received;
1137 dprint_status(task);
1139 status = task->tk_status;
1141 task->tk_action = call_decode;
1145 task->tk_status = 0;
1151 * Delay any retries for 3 seconds, then handle as if it
1154 rpc_delay(task, 3*HZ);
1156 task->tk_action = call_timeout;
1157 if (task->tk_client->cl_discrtry)
1158 xprt_force_disconnect(task->tk_xprt);
1162 rpc_force_rebind(clnt);
1163 task->tk_action = call_bind;
1166 task->tk_action = call_transmit;
1169 /* shutdown or soft timeout */
1170 rpc_exit(task, status);
1173 printk("%s: RPC call returned error %d\n",
1174 clnt->cl_protname, -status);
1175 rpc_exit(task, status);
1180 * 6a. Handle RPC timeout
1181 * We do not release the request slot, so we keep using the
1182 * same XID for all retransmits.
1185 call_timeout(struct rpc_task *task)
1187 struct rpc_clnt *clnt = task->tk_client;
1189 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1190 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1194 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1195 task->tk_timeouts++;
1197 if (RPC_IS_SOFT(task)) {
1198 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1199 clnt->cl_protname, clnt->cl_server);
1200 rpc_exit(task, -EIO);
1204 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1205 task->tk_flags |= RPC_CALL_MAJORSEEN;
1206 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1207 clnt->cl_protname, clnt->cl_server);
1209 rpc_force_rebind(clnt);
1212 clnt->cl_stats->rpcretrans++;
1213 task->tk_action = call_bind;
1214 task->tk_status = 0;
1218 * 7. Decode the RPC reply
1221 call_decode(struct rpc_task *task)
1223 struct rpc_clnt *clnt = task->tk_client;
1224 struct rpc_rqst *req = task->tk_rqstp;
1225 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1228 dprintk("RPC: %5u call_decode (status %d)\n",
1229 task->tk_pid, task->tk_status);
1231 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1232 printk(KERN_NOTICE "%s: server %s OK\n",
1233 clnt->cl_protname, clnt->cl_server);
1234 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1237 if (task->tk_status < 12) {
1238 if (!RPC_IS_SOFT(task)) {
1239 task->tk_action = call_bind;
1240 clnt->cl_stats->rpcretrans++;
1243 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1244 clnt->cl_protname, task->tk_status);
1245 task->tk_action = call_timeout;
1250 * Ensure that we see all writes made by xprt_complete_rqst()
1251 * before it changed req->rq_received.
1254 req->rq_rcv_buf.len = req->rq_private_buf.len;
1256 /* Check that the softirq receive buffer is valid */
1257 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1258 sizeof(req->rq_rcv_buf)) != 0);
1260 /* Verify the RPC header */
1261 p = call_verify(task);
1263 if (p == ERR_PTR(-EAGAIN))
1268 task->tk_action = rpc_exit_task;
1271 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1272 task->tk_msg.rpc_resp);
1274 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1278 req->rq_received = req->rq_private_buf.len = 0;
1279 task->tk_status = 0;
1280 if (task->tk_client->cl_discrtry)
1281 xprt_force_disconnect(task->tk_xprt);
1285 * 8. Refresh the credentials if rejected by the server
1288 call_refresh(struct rpc_task *task)
1290 dprint_status(task);
1292 task->tk_action = call_refreshresult;
1293 task->tk_status = 0;
1294 task->tk_client->cl_stats->rpcauthrefresh++;
1295 rpcauth_refreshcred(task);
1299 * 8a. Process the results of a credential refresh
1302 call_refreshresult(struct rpc_task *task)
1304 int status = task->tk_status;
1306 dprint_status(task);
1308 task->tk_status = 0;
1309 task->tk_action = call_reserve;
1310 if (status >= 0 && rpcauth_uptodatecred(task))
1312 if (status == -EACCES) {
1313 rpc_exit(task, -EACCES);
1316 task->tk_action = call_refresh;
1317 if (status != -ETIMEDOUT)
1318 rpc_delay(task, 3*HZ);
1323 * Call header serialization
1326 call_header(struct rpc_task *task)
1328 struct rpc_clnt *clnt = task->tk_client;
1329 struct rpc_rqst *req = task->tk_rqstp;
1330 __be32 *p = req->rq_svec[0].iov_base;
1332 /* FIXME: check buffer size? */
1334 p = xprt_skip_transport_header(task->tk_xprt, p);
1335 *p++ = req->rq_xid; /* XID */
1336 *p++ = htonl(RPC_CALL); /* CALL */
1337 *p++ = htonl(RPC_VERSION); /* RPC version */
1338 *p++ = htonl(clnt->cl_prog); /* program number */
1339 *p++ = htonl(clnt->cl_vers); /* program version */
1340 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1341 p = rpcauth_marshcred(task, p);
1342 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1347 * Reply header verification
1350 call_verify(struct rpc_task *task)
1352 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1353 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1354 __be32 *p = iov->iov_base;
1356 int error = -EACCES;
1358 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1359 /* RFC-1014 says that the representation of XDR data must be a
1360 * multiple of four bytes
1361 * - if it isn't pointer subtraction in the NFS client may give
1364 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1365 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1366 task->tk_rqstp->rq_rcv_buf.len);
1371 p += 1; /* skip XID */
1373 if ((n = ntohl(*p++)) != RPC_REPLY) {
1374 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1375 task->tk_pid, __FUNCTION__, n);
1378 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1381 switch ((n = ntohl(*p++))) {
1382 case RPC_AUTH_ERROR:
1385 dprintk("RPC: %5u %s: RPC call version "
1387 task->tk_pid, __FUNCTION__);
1388 error = -EPROTONOSUPPORT;
1391 dprintk("RPC: %5u %s: RPC call rejected, "
1392 "unknown error: %x\n",
1393 task->tk_pid, __FUNCTION__, n);
1398 switch ((n = ntohl(*p++))) {
1399 case RPC_AUTH_REJECTEDCRED:
1400 case RPC_AUTH_REJECTEDVERF:
1401 case RPCSEC_GSS_CREDPROBLEM:
1402 case RPCSEC_GSS_CTXPROBLEM:
1403 if (!task->tk_cred_retry)
1405 task->tk_cred_retry--;
1406 dprintk("RPC: %5u %s: retry stale creds\n",
1407 task->tk_pid, __FUNCTION__);
1408 rpcauth_invalcred(task);
1409 /* Ensure we obtain a new XID! */
1411 task->tk_action = call_refresh;
1413 case RPC_AUTH_BADCRED:
1414 case RPC_AUTH_BADVERF:
1415 /* possibly garbled cred/verf? */
1416 if (!task->tk_garb_retry)
1418 task->tk_garb_retry--;
1419 dprintk("RPC: %5u %s: retry garbled creds\n",
1420 task->tk_pid, __FUNCTION__);
1421 task->tk_action = call_bind;
1423 case RPC_AUTH_TOOWEAK:
1424 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1425 "authentication.\n", task->tk_client->cl_server);
1428 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1429 task->tk_pid, __FUNCTION__, n);
1432 dprintk("RPC: %5u %s: call rejected %d\n",
1433 task->tk_pid, __FUNCTION__, n);
1436 if (!(p = rpcauth_checkverf(task, p))) {
1437 dprintk("RPC: %5u %s: auth check failed\n",
1438 task->tk_pid, __FUNCTION__);
1439 goto out_garbage; /* bad verifier, retry */
1441 len = p - (__be32 *)iov->iov_base - 1;
1444 switch ((n = ntohl(*p++))) {
1447 case RPC_PROG_UNAVAIL:
1448 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1449 task->tk_pid, __FUNCTION__,
1450 (unsigned int)task->tk_client->cl_prog,
1451 task->tk_client->cl_server);
1452 error = -EPFNOSUPPORT;
1454 case RPC_PROG_MISMATCH:
1455 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1456 "server %s\n", task->tk_pid, __FUNCTION__,
1457 (unsigned int)task->tk_client->cl_prog,
1458 (unsigned int)task->tk_client->cl_vers,
1459 task->tk_client->cl_server);
1460 error = -EPROTONOSUPPORT;
1462 case RPC_PROC_UNAVAIL:
1463 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1464 "version %u on server %s\n",
1465 task->tk_pid, __FUNCTION__,
1466 task->tk_msg.rpc_proc,
1467 task->tk_client->cl_prog,
1468 task->tk_client->cl_vers,
1469 task->tk_client->cl_server);
1470 error = -EOPNOTSUPP;
1472 case RPC_GARBAGE_ARGS:
1473 dprintk("RPC: %5u %s: server saw garbage\n",
1474 task->tk_pid, __FUNCTION__);
1477 dprintk("RPC: %5u %s: server accept status: %x\n",
1478 task->tk_pid, __FUNCTION__, n);
1483 task->tk_client->cl_stats->rpcgarbage++;
1484 if (task->tk_garb_retry) {
1485 task->tk_garb_retry--;
1486 dprintk("RPC: %5u %s: retrying\n",
1487 task->tk_pid, __FUNCTION__);
1488 task->tk_action = call_bind;
1490 return ERR_PTR(-EAGAIN);
1495 rpc_exit(task, error);
1496 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1497 __FUNCTION__, error);
1498 return ERR_PTR(error);
1500 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1505 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1510 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1515 static struct rpc_procinfo rpcproc_null = {
1516 .p_encode = rpcproc_encode_null,
1517 .p_decode = rpcproc_decode_null,
1520 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1522 struct rpc_message msg = {
1523 .rpc_proc = &rpcproc_null,
1526 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1527 err = rpc_call_sync(clnt, &msg, flags);
1528 put_rpccred(msg.rpc_cred);
1532 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1534 struct rpc_message msg = {
1535 .rpc_proc = &rpcproc_null,
1538 struct rpc_task_setup task_setup_data = {
1540 .rpc_message = &msg,
1541 .callback_ops = &rpc_default_ops,
1544 return rpc_run_task(&task_setup_data);
1546 EXPORT_SYMBOL_GPL(rpc_call_null);
1549 void rpc_show_tasks(void)
1551 struct rpc_clnt *clnt;
1554 spin_lock(&rpc_client_lock);
1555 if (list_empty(&all_clients))
1557 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1558 "-rpcwait -action- ---ops--\n");
1559 list_for_each_entry(clnt, &all_clients, cl_clients) {
1560 if (list_empty(&clnt->cl_tasks))
1562 spin_lock(&clnt->cl_lock);
1563 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1564 const char *rpc_waitq = "none";
1567 if (t->tk_msg.rpc_proc)
1568 proc = t->tk_msg.rpc_proc->p_proc;
1572 if (RPC_IS_QUEUED(t))
1573 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1575 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1577 t->tk_flags, t->tk_status,
1579 (t->tk_client ? t->tk_client->cl_prog : 0),
1580 t->tk_rqstp, t->tk_timeout,
1582 t->tk_action, t->tk_ops);
1584 spin_unlock(&clnt->cl_lock);
1587 spin_unlock(&rpc_client_lock);