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 void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
506 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
509 static 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 ret = ERR_PTR(-ENOMEM);
543 if (task->tk_status != 0) {
544 ret = ERR_PTR(task->tk_status);
548 atomic_inc(&task->tk_count);
549 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
550 rpc_task_sigmask(task, &oldset);
552 rpc_restore_sigmask(&oldset);
557 EXPORT_SYMBOL_GPL(rpc_run_task);
560 * rpc_call_sync - Perform a synchronous RPC call
561 * @clnt: pointer to RPC client
562 * @msg: RPC call parameters
563 * @flags: RPC call flags
565 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
567 struct rpc_task *task;
568 struct rpc_task_setup task_setup_data = {
571 .callback_ops = &rpc_default_ops,
576 BUG_ON(flags & RPC_TASK_ASYNC);
578 task = rpc_run_task(&task_setup_data);
580 return PTR_ERR(task);
581 status = task->tk_status;
585 EXPORT_SYMBOL_GPL(rpc_call_sync);
588 * rpc_call_async - Perform an asynchronous RPC call
589 * @clnt: pointer to RPC client
590 * @msg: RPC call parameters
591 * @flags: RPC call flags
593 * @data: user call data
596 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
597 const struct rpc_call_ops *tk_ops, void *data)
599 struct rpc_task *task;
600 struct rpc_task_setup task_setup_data = {
603 .callback_ops = tk_ops,
604 .callback_data = data,
605 .flags = flags|RPC_TASK_ASYNC,
608 task = rpc_run_task(&task_setup_data);
610 return PTR_ERR(task);
614 EXPORT_SYMBOL_GPL(rpc_call_async);
617 rpc_call_setup(struct rpc_task *task, const struct rpc_message *msg, int flags)
620 task->tk_flags |= flags;
621 /* Bind the user cred */
622 if (task->tk_msg.rpc_cred != NULL)
623 rpcauth_holdcred(task);
625 rpcauth_bindcred(task);
627 if (task->tk_status == 0)
628 task->tk_action = call_start;
630 task->tk_action = rpc_exit_task;
632 EXPORT_SYMBOL_GPL(rpc_call_setup);
635 rpc_call_start(struct rpc_task *task)
637 task->tk_action = call_start;
639 EXPORT_SYMBOL_GPL(rpc_call_start);
642 * rpc_peeraddr - extract remote peer address from clnt's xprt
643 * @clnt: RPC client structure
644 * @buf: target buffer
645 * @size: length of target buffer
647 * Returns the number of bytes that are actually in the stored address.
649 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
652 struct rpc_xprt *xprt = clnt->cl_xprt;
654 bytes = sizeof(xprt->addr);
657 memcpy(buf, &clnt->cl_xprt->addr, bytes);
658 return xprt->addrlen;
660 EXPORT_SYMBOL_GPL(rpc_peeraddr);
663 * rpc_peeraddr2str - return remote peer address in printable format
664 * @clnt: RPC client structure
665 * @format: address format
668 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
670 struct rpc_xprt *xprt = clnt->cl_xprt;
672 if (xprt->address_strings[format] != NULL)
673 return xprt->address_strings[format];
675 return "unprintable";
677 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
680 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
682 struct rpc_xprt *xprt = clnt->cl_xprt;
683 if (xprt->ops->set_buffer_size)
684 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
686 EXPORT_SYMBOL_GPL(rpc_setbufsize);
689 * Return size of largest payload RPC client can support, in bytes
691 * For stream transports, this is one RPC record fragment (see RFC
692 * 1831), as we don't support multi-record requests yet. For datagram
693 * transports, this is the size of an IP packet minus the IP, UDP, and
696 size_t rpc_max_payload(struct rpc_clnt *clnt)
698 return clnt->cl_xprt->max_payload;
700 EXPORT_SYMBOL_GPL(rpc_max_payload);
703 * rpc_force_rebind - force transport to check that remote port is unchanged
704 * @clnt: client to rebind
707 void rpc_force_rebind(struct rpc_clnt *clnt)
709 if (clnt->cl_autobind)
710 xprt_clear_bound(clnt->cl_xprt);
712 EXPORT_SYMBOL_GPL(rpc_force_rebind);
715 * Restart an (async) RPC call. Usually called from within the
719 rpc_restart_call(struct rpc_task *task)
721 if (RPC_ASSASSINATED(task))
724 task->tk_action = call_start;
726 EXPORT_SYMBOL_GPL(rpc_restart_call);
731 * Other FSM states can be visited zero or more times, but
732 * this state is visited exactly once for each RPC.
735 call_start(struct rpc_task *task)
737 struct rpc_clnt *clnt = task->tk_client;
739 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
740 clnt->cl_protname, clnt->cl_vers,
741 task->tk_msg.rpc_proc->p_proc,
742 (RPC_IS_ASYNC(task) ? "async" : "sync"));
744 /* Increment call count */
745 task->tk_msg.rpc_proc->p_count++;
746 clnt->cl_stats->rpccnt++;
747 task->tk_action = call_reserve;
751 * 1. Reserve an RPC call slot
754 call_reserve(struct rpc_task *task)
758 if (!rpcauth_uptodatecred(task)) {
759 task->tk_action = call_refresh;
764 task->tk_action = call_reserveresult;
769 * 1b. Grok the result of xprt_reserve()
772 call_reserveresult(struct rpc_task *task)
774 int status = task->tk_status;
779 * After a call to xprt_reserve(), we must have either
780 * a request slot or else an error status.
784 if (task->tk_rqstp) {
785 task->tk_action = call_allocate;
789 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
790 __FUNCTION__, status);
791 rpc_exit(task, -EIO);
796 * Even though there was an error, we may have acquired
797 * a request slot somehow. Make sure not to leak it.
799 if (task->tk_rqstp) {
800 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
801 __FUNCTION__, status);
806 case -EAGAIN: /* woken up; retry */
807 task->tk_action = call_reserve;
809 case -EIO: /* probably a shutdown */
812 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
813 __FUNCTION__, status);
816 rpc_exit(task, status);
820 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
821 * (Note: buffer memory is freed in xprt_release).
824 call_allocate(struct rpc_task *task)
826 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
827 struct rpc_rqst *req = task->tk_rqstp;
828 struct rpc_xprt *xprt = task->tk_xprt;
829 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
834 task->tk_action = call_bind;
839 if (proc->p_proc != 0) {
840 BUG_ON(proc->p_arglen == 0);
841 if (proc->p_decode != NULL)
842 BUG_ON(proc->p_replen == 0);
846 * Calculate the size (in quads) of the RPC call
847 * and reply headers, and convert both values
850 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
851 req->rq_callsize <<= 2;
852 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
853 req->rq_rcvsize <<= 2;
855 req->rq_buffer = xprt->ops->buf_alloc(task,
856 req->rq_callsize + req->rq_rcvsize);
857 if (req->rq_buffer != NULL)
860 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
862 if (RPC_IS_ASYNC(task) || !signalled()) {
863 task->tk_action = call_allocate;
864 rpc_delay(task, HZ>>4);
868 rpc_exit(task, -ERESTARTSYS);
872 rpc_task_need_encode(struct rpc_task *task)
874 return task->tk_rqstp->rq_snd_buf.len == 0;
878 rpc_task_force_reencode(struct rpc_task *task)
880 task->tk_rqstp->rq_snd_buf.len = 0;
884 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
886 buf->head[0].iov_base = start;
887 buf->head[0].iov_len = len;
888 buf->tail[0].iov_len = 0;
896 * 3. Encode arguments of an RPC call
899 call_encode(struct rpc_task *task)
901 struct rpc_rqst *req = task->tk_rqstp;
907 rpc_xdr_buf_init(&req->rq_snd_buf,
910 rpc_xdr_buf_init(&req->rq_rcv_buf,
911 (char *)req->rq_buffer + req->rq_callsize,
914 /* Encode header and provided arguments */
915 encode = task->tk_msg.rpc_proc->p_encode;
916 if (!(p = call_header(task))) {
917 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
918 rpc_exit(task, -EIO);
924 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
925 task->tk_msg.rpc_argp);
926 if (task->tk_status == -ENOMEM) {
927 /* XXX: Is this sane? */
928 rpc_delay(task, 3*HZ);
929 task->tk_status = -EAGAIN;
934 * 4. Get the server port number if not yet set
937 call_bind(struct rpc_task *task)
939 struct rpc_xprt *xprt = task->tk_xprt;
943 task->tk_action = call_connect;
944 if (!xprt_bound(xprt)) {
945 task->tk_action = call_bind_status;
946 task->tk_timeout = xprt->bind_timeout;
947 xprt->ops->rpcbind(task);
952 * 4a. Sort out bind result
955 call_bind_status(struct rpc_task *task)
959 if (task->tk_status >= 0) {
962 task->tk_action = call_connect;
966 switch (task->tk_status) {
968 dprintk("RPC: %5u rpcbind waiting for another request "
969 "to finish\n", task->tk_pid);
970 /* avoid busy-waiting here -- could be a network outage. */
971 rpc_delay(task, 5*HZ);
974 dprintk("RPC: %5u remote rpcbind: RPC program/version "
975 "unavailable\n", task->tk_pid);
976 /* fail immediately if this is an RPC ping */
977 if (task->tk_msg.rpc_proc->p_proc == 0) {
978 status = -EOPNOTSUPP;
981 rpc_delay(task, 3*HZ);
984 dprintk("RPC: %5u rpcbind request timed out\n",
988 /* server doesn't support any rpcbind version we know of */
989 dprintk("RPC: %5u remote rpcbind service unavailable\n",
992 case -EPROTONOSUPPORT:
993 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
996 task->tk_action = call_bind;
999 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1000 task->tk_pid, -task->tk_status);
1003 rpc_exit(task, status);
1007 task->tk_action = call_timeout;
1011 * 4b. Connect to the RPC server
1014 call_connect(struct rpc_task *task)
1016 struct rpc_xprt *xprt = task->tk_xprt;
1018 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1020 (xprt_connected(xprt) ? "is" : "is not"));
1022 task->tk_action = call_transmit;
1023 if (!xprt_connected(xprt)) {
1024 task->tk_action = call_connect_status;
1025 if (task->tk_status < 0)
1032 * 4c. Sort out connect result
1035 call_connect_status(struct rpc_task *task)
1037 struct rpc_clnt *clnt = task->tk_client;
1038 int status = task->tk_status;
1040 dprint_status(task);
1042 task->tk_status = 0;
1044 clnt->cl_stats->netreconn++;
1045 task->tk_action = call_transmit;
1049 /* Something failed: remote service port may have changed */
1050 rpc_force_rebind(clnt);
1055 task->tk_action = call_bind;
1056 if (!RPC_IS_SOFT(task))
1058 /* if soft mounted, test if we've timed out */
1060 task->tk_action = call_timeout;
1063 rpc_exit(task, -EIO);
1067 * 5. Transmit the RPC request, and wait for reply
1070 call_transmit(struct rpc_task *task)
1072 dprint_status(task);
1074 task->tk_action = call_status;
1075 if (task->tk_status < 0)
1077 task->tk_status = xprt_prepare_transmit(task);
1078 if (task->tk_status != 0)
1080 task->tk_action = call_transmit_status;
1081 /* Encode here so that rpcsec_gss can use correct sequence number. */
1082 if (rpc_task_need_encode(task)) {
1083 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1085 /* Did the encode result in an error condition? */
1086 if (task->tk_status != 0)
1089 xprt_transmit(task);
1090 if (task->tk_status < 0)
1093 * On success, ensure that we call xprt_end_transmit() before sleeping
1094 * in order to allow access to the socket to other RPC requests.
1096 call_transmit_status(task);
1097 if (task->tk_msg.rpc_proc->p_decode != NULL)
1099 task->tk_action = rpc_exit_task;
1100 rpc_wake_up_task(task);
1104 * 5a. Handle cleanup after a transmission
1107 call_transmit_status(struct rpc_task *task)
1109 task->tk_action = call_status;
1111 * Special case: if we've been waiting on the socket's write_space()
1112 * callback, then don't call xprt_end_transmit().
1114 if (task->tk_status == -EAGAIN)
1116 xprt_end_transmit(task);
1117 rpc_task_force_reencode(task);
1121 * 6. Sort out the RPC call status
1124 call_status(struct rpc_task *task)
1126 struct rpc_clnt *clnt = task->tk_client;
1127 struct rpc_rqst *req = task->tk_rqstp;
1130 if (req->rq_received > 0 && !req->rq_bytes_sent)
1131 task->tk_status = req->rq_received;
1133 dprint_status(task);
1135 status = task->tk_status;
1137 task->tk_action = call_decode;
1141 task->tk_status = 0;
1147 * Delay any retries for 3 seconds, then handle as if it
1150 rpc_delay(task, 3*HZ);
1152 task->tk_action = call_timeout;
1153 if (task->tk_client->cl_discrtry)
1154 xprt_force_disconnect(task->tk_xprt);
1158 rpc_force_rebind(clnt);
1159 task->tk_action = call_bind;
1162 task->tk_action = call_transmit;
1165 /* shutdown or soft timeout */
1166 rpc_exit(task, status);
1169 printk("%s: RPC call returned error %d\n",
1170 clnt->cl_protname, -status);
1171 rpc_exit(task, status);
1176 * 6a. Handle RPC timeout
1177 * We do not release the request slot, so we keep using the
1178 * same XID for all retransmits.
1181 call_timeout(struct rpc_task *task)
1183 struct rpc_clnt *clnt = task->tk_client;
1185 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1186 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1190 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1191 task->tk_timeouts++;
1193 if (RPC_IS_SOFT(task)) {
1194 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1195 clnt->cl_protname, clnt->cl_server);
1196 rpc_exit(task, -EIO);
1200 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1201 task->tk_flags |= RPC_CALL_MAJORSEEN;
1202 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1203 clnt->cl_protname, clnt->cl_server);
1205 rpc_force_rebind(clnt);
1208 clnt->cl_stats->rpcretrans++;
1209 task->tk_action = call_bind;
1210 task->tk_status = 0;
1214 * 7. Decode the RPC reply
1217 call_decode(struct rpc_task *task)
1219 struct rpc_clnt *clnt = task->tk_client;
1220 struct rpc_rqst *req = task->tk_rqstp;
1221 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1224 dprintk("RPC: %5u call_decode (status %d)\n",
1225 task->tk_pid, task->tk_status);
1227 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1228 printk(KERN_NOTICE "%s: server %s OK\n",
1229 clnt->cl_protname, clnt->cl_server);
1230 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1233 if (task->tk_status < 12) {
1234 if (!RPC_IS_SOFT(task)) {
1235 task->tk_action = call_bind;
1236 clnt->cl_stats->rpcretrans++;
1239 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1240 clnt->cl_protname, task->tk_status);
1241 task->tk_action = call_timeout;
1246 * Ensure that we see all writes made by xprt_complete_rqst()
1247 * before it changed req->rq_received.
1250 req->rq_rcv_buf.len = req->rq_private_buf.len;
1252 /* Check that the softirq receive buffer is valid */
1253 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1254 sizeof(req->rq_rcv_buf)) != 0);
1256 /* Verify the RPC header */
1257 p = call_verify(task);
1259 if (p == ERR_PTR(-EAGAIN))
1264 task->tk_action = rpc_exit_task;
1267 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1268 task->tk_msg.rpc_resp);
1270 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1274 req->rq_received = req->rq_private_buf.len = 0;
1275 task->tk_status = 0;
1276 if (task->tk_client->cl_discrtry)
1277 xprt_force_disconnect(task->tk_xprt);
1281 * 8. Refresh the credentials if rejected by the server
1284 call_refresh(struct rpc_task *task)
1286 dprint_status(task);
1288 task->tk_action = call_refreshresult;
1289 task->tk_status = 0;
1290 task->tk_client->cl_stats->rpcauthrefresh++;
1291 rpcauth_refreshcred(task);
1295 * 8a. Process the results of a credential refresh
1298 call_refreshresult(struct rpc_task *task)
1300 int status = task->tk_status;
1302 dprint_status(task);
1304 task->tk_status = 0;
1305 task->tk_action = call_reserve;
1306 if (status >= 0 && rpcauth_uptodatecred(task))
1308 if (status == -EACCES) {
1309 rpc_exit(task, -EACCES);
1312 task->tk_action = call_refresh;
1313 if (status != -ETIMEDOUT)
1314 rpc_delay(task, 3*HZ);
1319 * Call header serialization
1322 call_header(struct rpc_task *task)
1324 struct rpc_clnt *clnt = task->tk_client;
1325 struct rpc_rqst *req = task->tk_rqstp;
1326 __be32 *p = req->rq_svec[0].iov_base;
1328 /* FIXME: check buffer size? */
1330 p = xprt_skip_transport_header(task->tk_xprt, p);
1331 *p++ = req->rq_xid; /* XID */
1332 *p++ = htonl(RPC_CALL); /* CALL */
1333 *p++ = htonl(RPC_VERSION); /* RPC version */
1334 *p++ = htonl(clnt->cl_prog); /* program number */
1335 *p++ = htonl(clnt->cl_vers); /* program version */
1336 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1337 p = rpcauth_marshcred(task, p);
1338 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1343 * Reply header verification
1346 call_verify(struct rpc_task *task)
1348 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1349 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1350 __be32 *p = iov->iov_base;
1352 int error = -EACCES;
1354 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1355 /* RFC-1014 says that the representation of XDR data must be a
1356 * multiple of four bytes
1357 * - if it isn't pointer subtraction in the NFS client may give
1360 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1361 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1362 task->tk_rqstp->rq_rcv_buf.len);
1367 p += 1; /* skip XID */
1369 if ((n = ntohl(*p++)) != RPC_REPLY) {
1370 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1371 task->tk_pid, __FUNCTION__, n);
1374 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1377 switch ((n = ntohl(*p++))) {
1378 case RPC_AUTH_ERROR:
1381 dprintk("RPC: %5u %s: RPC call version "
1383 task->tk_pid, __FUNCTION__);
1384 error = -EPROTONOSUPPORT;
1387 dprintk("RPC: %5u %s: RPC call rejected, "
1388 "unknown error: %x\n",
1389 task->tk_pid, __FUNCTION__, n);
1394 switch ((n = ntohl(*p++))) {
1395 case RPC_AUTH_REJECTEDCRED:
1396 case RPC_AUTH_REJECTEDVERF:
1397 case RPCSEC_GSS_CREDPROBLEM:
1398 case RPCSEC_GSS_CTXPROBLEM:
1399 if (!task->tk_cred_retry)
1401 task->tk_cred_retry--;
1402 dprintk("RPC: %5u %s: retry stale creds\n",
1403 task->tk_pid, __FUNCTION__);
1404 rpcauth_invalcred(task);
1405 /* Ensure we obtain a new XID! */
1407 task->tk_action = call_refresh;
1409 case RPC_AUTH_BADCRED:
1410 case RPC_AUTH_BADVERF:
1411 /* possibly garbled cred/verf? */
1412 if (!task->tk_garb_retry)
1414 task->tk_garb_retry--;
1415 dprintk("RPC: %5u %s: retry garbled creds\n",
1416 task->tk_pid, __FUNCTION__);
1417 task->tk_action = call_bind;
1419 case RPC_AUTH_TOOWEAK:
1420 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1421 "authentication.\n", task->tk_client->cl_server);
1424 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1425 task->tk_pid, __FUNCTION__, n);
1428 dprintk("RPC: %5u %s: call rejected %d\n",
1429 task->tk_pid, __FUNCTION__, n);
1432 if (!(p = rpcauth_checkverf(task, p))) {
1433 dprintk("RPC: %5u %s: auth check failed\n",
1434 task->tk_pid, __FUNCTION__);
1435 goto out_garbage; /* bad verifier, retry */
1437 len = p - (__be32 *)iov->iov_base - 1;
1440 switch ((n = ntohl(*p++))) {
1443 case RPC_PROG_UNAVAIL:
1444 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1445 task->tk_pid, __FUNCTION__,
1446 (unsigned int)task->tk_client->cl_prog,
1447 task->tk_client->cl_server);
1448 error = -EPFNOSUPPORT;
1450 case RPC_PROG_MISMATCH:
1451 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1452 "server %s\n", task->tk_pid, __FUNCTION__,
1453 (unsigned int)task->tk_client->cl_prog,
1454 (unsigned int)task->tk_client->cl_vers,
1455 task->tk_client->cl_server);
1456 error = -EPROTONOSUPPORT;
1458 case RPC_PROC_UNAVAIL:
1459 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1460 "version %u on server %s\n",
1461 task->tk_pid, __FUNCTION__,
1462 task->tk_msg.rpc_proc,
1463 task->tk_client->cl_prog,
1464 task->tk_client->cl_vers,
1465 task->tk_client->cl_server);
1466 error = -EOPNOTSUPP;
1468 case RPC_GARBAGE_ARGS:
1469 dprintk("RPC: %5u %s: server saw garbage\n",
1470 task->tk_pid, __FUNCTION__);
1473 dprintk("RPC: %5u %s: server accept status: %x\n",
1474 task->tk_pid, __FUNCTION__, n);
1479 task->tk_client->cl_stats->rpcgarbage++;
1480 if (task->tk_garb_retry) {
1481 task->tk_garb_retry--;
1482 dprintk("RPC: %5u %s: retrying\n",
1483 task->tk_pid, __FUNCTION__);
1484 task->tk_action = call_bind;
1486 return ERR_PTR(-EAGAIN);
1491 rpc_exit(task, error);
1492 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1493 __FUNCTION__, error);
1494 return ERR_PTR(error);
1496 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1501 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1506 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1511 static struct rpc_procinfo rpcproc_null = {
1512 .p_encode = rpcproc_encode_null,
1513 .p_decode = rpcproc_decode_null,
1516 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1518 struct rpc_message msg = {
1519 .rpc_proc = &rpcproc_null,
1522 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1523 err = rpc_call_sync(clnt, &msg, flags);
1524 put_rpccred(msg.rpc_cred);
1528 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1530 struct rpc_message msg = {
1531 .rpc_proc = &rpcproc_null,
1534 struct rpc_task_setup task_setup_data = {
1536 .rpc_message = &msg,
1537 .callback_ops = &rpc_default_ops,
1540 return rpc_run_task(&task_setup_data);
1542 EXPORT_SYMBOL_GPL(rpc_call_null);
1545 void rpc_show_tasks(void)
1547 struct rpc_clnt *clnt;
1550 spin_lock(&rpc_client_lock);
1551 if (list_empty(&all_clients))
1553 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1554 "-rpcwait -action- ---ops--\n");
1555 list_for_each_entry(clnt, &all_clients, cl_clients) {
1556 if (list_empty(&clnt->cl_tasks))
1558 spin_lock(&clnt->cl_lock);
1559 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1560 const char *rpc_waitq = "none";
1563 if (t->tk_msg.rpc_proc)
1564 proc = t->tk_msg.rpc_proc->p_proc;
1568 if (RPC_IS_QUEUED(t))
1569 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1571 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1573 t->tk_flags, t->tk_status,
1575 (t->tk_client ? t->tk_client->cl_prog : 0),
1576 t->tk_rqstp, t->tk_timeout,
1578 t->tk_action, t->tk_ops);
1580 spin_unlock(&clnt->cl_lock);
1583 spin_unlock(&rpc_client_lock);