2 * linux/net/sunrpc/clnt.c
4 * This file contains the high-level RPC interface.
5 * It is modeled as a finite state machine to support both synchronous
6 * and asynchronous requests.
8 * - RPC header generation and argument serialization.
9 * - Credential refresh.
10 * - TCP connect handling.
11 * - Retry of operation when it is suspected the operation failed because
12 * of uid squashing on the server, or when the credentials were stale
13 * and need to be refreshed, or when a packet was damaged in transit.
14 * This may be have to be moved to the VFS layer.
16 * NB: BSD uses a more intelligent approach to guessing when a request
17 * or reply has been lost by keeping the RTO estimate for each procedure.
18 * We currently make do with a constant timeout value.
20 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
21 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
24 #include <asm/system.h>
26 #include <linux/module.h>
27 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/smp_lock.h>
31 #include <linux/utsname.h>
32 #include <linux/workqueue.h>
34 #include <linux/sunrpc/clnt.h>
35 #include <linux/sunrpc/rpc_pipe_fs.h>
36 #include <linux/sunrpc/metrics.h>
40 # define RPCDBG_FACILITY RPCDBG_CALL
43 #define dprint_status(t) \
44 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
45 __FUNCTION__, t->tk_status)
48 * All RPC clients are linked into this list
50 static LIST_HEAD(all_clients);
51 static DEFINE_SPINLOCK(rpc_client_lock);
53 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
56 static void call_start(struct rpc_task *task);
57 static void call_reserve(struct rpc_task *task);
58 static void call_reserveresult(struct rpc_task *task);
59 static void call_allocate(struct rpc_task *task);
60 static void call_encode(struct rpc_task *task);
61 static void call_decode(struct rpc_task *task);
62 static void call_bind(struct rpc_task *task);
63 static void call_bind_status(struct rpc_task *task);
64 static void call_transmit(struct rpc_task *task);
65 static void call_status(struct rpc_task *task);
66 static void call_transmit_status(struct rpc_task *task);
67 static void call_refresh(struct rpc_task *task);
68 static void call_refreshresult(struct rpc_task *task);
69 static void call_timeout(struct rpc_task *task);
70 static void call_connect(struct rpc_task *task);
71 static void call_connect_status(struct rpc_task *task);
72 static __be32 * call_header(struct rpc_task *task);
73 static __be32 * call_verify(struct rpc_task *task);
75 static int rpc_ping(struct rpc_clnt *clnt, int flags);
77 static void rpc_register_client(struct rpc_clnt *clnt)
79 spin_lock(&rpc_client_lock);
80 list_add(&clnt->cl_clients, &all_clients);
81 spin_unlock(&rpc_client_lock);
84 static void rpc_unregister_client(struct rpc_clnt *clnt)
86 spin_lock(&rpc_client_lock);
87 list_del(&clnt->cl_clients);
88 spin_unlock(&rpc_client_lock);
92 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
94 static uint32_t clntid;
97 clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
98 clnt->cl_dentry = ERR_PTR(-ENOENT);
102 clnt->cl_vfsmnt = rpc_get_mount();
103 if (IS_ERR(clnt->cl_vfsmnt))
104 return PTR_ERR(clnt->cl_vfsmnt);
107 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
108 "%s/clnt%x", dir_name,
109 (unsigned int)clntid++);
110 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
111 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
112 if (!IS_ERR(clnt->cl_dentry))
114 error = PTR_ERR(clnt->cl_dentry);
115 if (error != -EEXIST) {
116 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
117 clnt->cl_pathname, error);
124 static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor)
126 struct rpc_version *version;
127 struct rpc_clnt *clnt = NULL;
128 struct rpc_auth *auth;
132 /* sanity check the name before trying to print it */
134 len = strlen(servname);
135 if (len > RPC_MAXNETNAMELEN)
139 dprintk("RPC: creating %s client for %s (xprt %p)\n",
140 program->name, servname, xprt);
148 if (vers >= program->nrvers || !(version = program->version[vers]))
152 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
155 clnt->cl_parent = clnt;
157 clnt->cl_server = clnt->cl_inline_name;
158 if (len > sizeof(clnt->cl_inline_name)) {
159 char *buf = kmalloc(len, GFP_KERNEL);
161 clnt->cl_server = buf;
163 len = sizeof(clnt->cl_inline_name);
165 strlcpy(clnt->cl_server, servname, len);
167 clnt->cl_xprt = xprt;
168 clnt->cl_procinfo = version->procs;
169 clnt->cl_maxproc = version->nrprocs;
170 clnt->cl_protname = program->name;
171 clnt->cl_prog = program->number;
172 clnt->cl_vers = version->number;
173 clnt->cl_stats = program->stats;
174 clnt->cl_metrics = rpc_alloc_iostats(clnt);
176 if (clnt->cl_metrics == NULL)
178 clnt->cl_program = program;
179 INIT_LIST_HEAD(&clnt->cl_tasks);
180 spin_lock_init(&clnt->cl_lock);
182 if (!xprt_bound(clnt->cl_xprt))
183 clnt->cl_autobind = 1;
185 clnt->cl_rtt = &clnt->cl_rtt_default;
186 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
188 kref_init(&clnt->cl_kref);
190 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
194 auth = rpcauth_create(flavor, clnt);
196 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
202 /* save the nodename */
203 clnt->cl_nodelen = strlen(utsname()->nodename);
204 if (clnt->cl_nodelen > UNX_MAXNODENAME)
205 clnt->cl_nodelen = UNX_MAXNODENAME;
206 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
207 rpc_register_client(clnt);
211 if (!IS_ERR(clnt->cl_dentry)) {
212 rpc_rmdir(clnt->cl_dentry);
216 rpc_free_iostats(clnt->cl_metrics);
218 if (clnt->cl_server != clnt->cl_inline_name)
219 kfree(clnt->cl_server);
230 * rpc_create - create an RPC client and transport with one call
231 * @args: rpc_clnt create argument structure
233 * Creates and initializes an RPC transport and an RPC client.
235 * It can ping the server in order to determine if it is up, and to see if
236 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
237 * this behavior so asynchronous tasks can also use rpc_create.
239 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
241 struct rpc_xprt *xprt;
242 struct rpc_clnt *clnt;
243 struct xprt_create xprtargs = {
244 .ident = args->protocol,
245 .srcaddr = args->saddress,
246 .dstaddr = args->address,
247 .addrlen = args->addrsize,
248 .timeout = args->timeout
252 xprt = xprt_create_transport(&xprtargs);
254 return (struct rpc_clnt *)xprt;
257 * If the caller chooses not to specify a hostname, whip
258 * up a string representation of the passed-in address.
260 if (args->servername == NULL) {
261 struct sockaddr_in *addr =
262 (struct sockaddr_in *) args->address;
263 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
264 NIPQUAD(addr->sin_addr.s_addr));
265 args->servername = servername;
269 * By default, kernel RPC client connects from a reserved port.
270 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
271 * but it is always enabled for rpciod, which handles the connect
275 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
278 clnt = rpc_new_client(xprt, args->servername, args->program,
279 args->version, args->authflavor);
283 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
284 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
286 rpc_shutdown_client(clnt);
291 clnt->cl_softrtry = 1;
292 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
293 clnt->cl_softrtry = 0;
295 if (args->flags & RPC_CLNT_CREATE_INTR)
297 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
298 clnt->cl_autobind = 1;
299 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
300 clnt->cl_discrtry = 1;
304 EXPORT_SYMBOL_GPL(rpc_create);
307 * This function clones the RPC client structure. It allows us to share the
308 * same transport while varying parameters such as the authentication
312 rpc_clone_client(struct rpc_clnt *clnt)
314 struct rpc_clnt *new;
317 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
320 new->cl_parent = clnt;
321 /* Turn off autobind on clones */
322 new->cl_autobind = 0;
323 INIT_LIST_HEAD(&new->cl_tasks);
324 spin_lock_init(&new->cl_lock);
325 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
326 new->cl_metrics = rpc_alloc_iostats(clnt);
327 if (new->cl_metrics == NULL)
329 kref_init(&new->cl_kref);
330 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
334 atomic_inc(&new->cl_auth->au_count);
335 xprt_get(clnt->cl_xprt);
336 kref_get(&clnt->cl_kref);
337 rpc_register_client(new);
341 rpc_free_iostats(new->cl_metrics);
345 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
348 EXPORT_SYMBOL_GPL(rpc_clone_client);
351 * Properly shut down an RPC client, terminating all outstanding
354 void rpc_shutdown_client(struct rpc_clnt *clnt)
356 dprintk("RPC: shutting down %s client for %s\n",
357 clnt->cl_protname, clnt->cl_server);
359 while (!list_empty(&clnt->cl_tasks)) {
360 rpc_killall_tasks(clnt);
361 wait_event_timeout(destroy_wait,
362 list_empty(&clnt->cl_tasks), 1*HZ);
365 rpc_release_client(clnt);
367 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
373 rpc_free_client(struct kref *kref)
375 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
377 dprintk("RPC: destroying %s client for %s\n",
378 clnt->cl_protname, clnt->cl_server);
379 if (!IS_ERR(clnt->cl_dentry)) {
380 rpc_rmdir(clnt->cl_dentry);
383 if (clnt->cl_parent != clnt) {
384 rpc_release_client(clnt->cl_parent);
387 if (clnt->cl_server != clnt->cl_inline_name)
388 kfree(clnt->cl_server);
390 rpc_unregister_client(clnt);
391 rpc_free_iostats(clnt->cl_metrics);
392 clnt->cl_metrics = NULL;
393 xprt_put(clnt->cl_xprt);
402 rpc_free_auth(struct kref *kref)
404 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
406 if (clnt->cl_auth == NULL) {
407 rpc_free_client(kref);
412 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
413 * release remaining GSS contexts. This mechanism ensures
414 * that it can do so safely.
417 rpcauth_release(clnt->cl_auth);
418 clnt->cl_auth = NULL;
419 kref_put(kref, rpc_free_client);
423 * Release reference to the RPC client
426 rpc_release_client(struct rpc_clnt *clnt)
428 dprintk("RPC: rpc_release_client(%p)\n", clnt);
430 if (list_empty(&clnt->cl_tasks))
431 wake_up(&destroy_wait);
432 kref_put(&clnt->cl_kref, rpc_free_auth);
436 * rpc_bind_new_program - bind a new RPC program to an existing client
437 * @old - old rpc_client
438 * @program - rpc program to set
439 * @vers - rpc program version
441 * Clones the rpc client and sets up a new RPC program. This is mainly
442 * of use for enabling different RPC programs to share the same transport.
443 * The Sun NFSv2/v3 ACL protocol can do this.
445 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
446 struct rpc_program *program,
449 struct rpc_clnt *clnt;
450 struct rpc_version *version;
453 BUG_ON(vers >= program->nrvers || !program->version[vers]);
454 version = program->version[vers];
455 clnt = rpc_clone_client(old);
458 clnt->cl_procinfo = version->procs;
459 clnt->cl_maxproc = version->nrprocs;
460 clnt->cl_protname = program->name;
461 clnt->cl_prog = program->number;
462 clnt->cl_vers = version->number;
463 clnt->cl_stats = program->stats;
464 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
466 rpc_shutdown_client(clnt);
472 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
475 * Default callback for async RPC calls
478 rpc_default_callback(struct rpc_task *task, void *data)
482 static const struct rpc_call_ops rpc_default_ops = {
483 .rpc_call_done = rpc_default_callback,
487 * Export the signal mask handling for synchronous code that
488 * sleeps on RPC calls
490 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
492 static void rpc_save_sigmask(sigset_t *oldset, int intr)
494 unsigned long sigallow = sigmask(SIGKILL);
497 /* Block all signals except those listed in sigallow */
499 sigallow |= RPC_INTR_SIGNALS;
500 siginitsetinv(&sigmask, sigallow);
501 sigprocmask(SIG_BLOCK, &sigmask, oldset);
504 static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
506 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
509 static inline void rpc_restore_sigmask(sigset_t *oldset)
511 sigprocmask(SIG_SETMASK, oldset, NULL);
514 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
516 rpc_save_sigmask(oldset, clnt->cl_intr);
518 EXPORT_SYMBOL_GPL(rpc_clnt_sigmask);
520 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
522 rpc_restore_sigmask(oldset);
524 EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask);
527 struct rpc_task *rpc_do_run_task(struct rpc_clnt *clnt,
528 struct rpc_message *msg,
530 const struct rpc_call_ops *ops,
533 struct rpc_task *task, *ret;
536 task = rpc_new_task(clnt, flags, ops, data);
538 rpc_release_calldata(ops, data);
539 return ERR_PTR(-ENOMEM);
542 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
543 rpc_task_sigmask(task, &oldset);
545 rpc_call_setup(task, msg, 0);
546 if (task->tk_status != 0) {
547 ret = ERR_PTR(task->tk_status);
552 atomic_inc(&task->tk_count);
556 rpc_restore_sigmask(&oldset);
561 * rpc_call_sync - Perform a synchronous RPC call
562 * @clnt: pointer to RPC client
563 * @msg: RPC call parameters
564 * @flags: RPC call flags
566 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
568 struct rpc_task *task;
571 BUG_ON(flags & RPC_TASK_ASYNC);
573 task = rpc_do_run_task(clnt, msg, flags, &rpc_default_ops, NULL);
575 return PTR_ERR(task);
576 status = task->tk_status;
580 EXPORT_SYMBOL_GPL(rpc_call_sync);
583 * rpc_call_async - Perform an asynchronous RPC call
584 * @clnt: pointer to RPC client
585 * @msg: RPC call parameters
586 * @flags: RPC call flags
588 * @data: user call data
591 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
592 const struct rpc_call_ops *tk_ops, void *data)
594 struct rpc_task *task;
596 task = rpc_do_run_task(clnt, msg, flags|RPC_TASK_ASYNC, tk_ops, data);
598 return PTR_ERR(task);
602 EXPORT_SYMBOL_GPL(rpc_call_async);
605 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
606 * @clnt: pointer to RPC client
609 * @data: user call data
611 struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
612 const struct rpc_call_ops *tk_ops,
615 return rpc_do_run_task(clnt, NULL, flags, tk_ops, data);
617 EXPORT_SYMBOL_GPL(rpc_run_task);
620 rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
623 task->tk_flags |= flags;
624 /* Bind the user cred */
625 if (task->tk_msg.rpc_cred != NULL)
626 rpcauth_holdcred(task);
628 rpcauth_bindcred(task);
630 if (task->tk_status == 0)
631 task->tk_action = call_start;
633 task->tk_action = rpc_exit_task;
635 EXPORT_SYMBOL_GPL(rpc_call_setup);
638 * rpc_peeraddr - extract remote peer address from clnt's xprt
639 * @clnt: RPC client structure
640 * @buf: target buffer
641 * @size: length of target buffer
643 * Returns the number of bytes that are actually in the stored address.
645 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
648 struct rpc_xprt *xprt = clnt->cl_xprt;
650 bytes = sizeof(xprt->addr);
653 memcpy(buf, &clnt->cl_xprt->addr, bytes);
654 return xprt->addrlen;
656 EXPORT_SYMBOL_GPL(rpc_peeraddr);
659 * rpc_peeraddr2str - return remote peer address in printable format
660 * @clnt: RPC client structure
661 * @format: address format
664 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
666 struct rpc_xprt *xprt = clnt->cl_xprt;
668 if (xprt->address_strings[format] != NULL)
669 return xprt->address_strings[format];
671 return "unprintable";
673 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
676 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
678 struct rpc_xprt *xprt = clnt->cl_xprt;
679 if (xprt->ops->set_buffer_size)
680 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
682 EXPORT_SYMBOL_GPL(rpc_setbufsize);
685 * Return size of largest payload RPC client can support, in bytes
687 * For stream transports, this is one RPC record fragment (see RFC
688 * 1831), as we don't support multi-record requests yet. For datagram
689 * transports, this is the size of an IP packet minus the IP, UDP, and
692 size_t rpc_max_payload(struct rpc_clnt *clnt)
694 return clnt->cl_xprt->max_payload;
696 EXPORT_SYMBOL_GPL(rpc_max_payload);
699 * rpc_force_rebind - force transport to check that remote port is unchanged
700 * @clnt: client to rebind
703 void rpc_force_rebind(struct rpc_clnt *clnt)
705 if (clnt->cl_autobind)
706 xprt_clear_bound(clnt->cl_xprt);
708 EXPORT_SYMBOL_GPL(rpc_force_rebind);
711 * Restart an (async) RPC call. Usually called from within the
715 rpc_restart_call(struct rpc_task *task)
717 if (RPC_ASSASSINATED(task))
720 task->tk_action = call_start;
722 EXPORT_SYMBOL_GPL(rpc_restart_call);
727 * Other FSM states can be visited zero or more times, but
728 * this state is visited exactly once for each RPC.
731 call_start(struct rpc_task *task)
733 struct rpc_clnt *clnt = task->tk_client;
735 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
736 clnt->cl_protname, clnt->cl_vers,
737 task->tk_msg.rpc_proc->p_proc,
738 (RPC_IS_ASYNC(task) ? "async" : "sync"));
740 /* Increment call count */
741 task->tk_msg.rpc_proc->p_count++;
742 clnt->cl_stats->rpccnt++;
743 task->tk_action = call_reserve;
747 * 1. Reserve an RPC call slot
750 call_reserve(struct rpc_task *task)
754 if (!rpcauth_uptodatecred(task)) {
755 task->tk_action = call_refresh;
760 task->tk_action = call_reserveresult;
765 * 1b. Grok the result of xprt_reserve()
768 call_reserveresult(struct rpc_task *task)
770 int status = task->tk_status;
775 * After a call to xprt_reserve(), we must have either
776 * a request slot or else an error status.
780 if (task->tk_rqstp) {
781 task->tk_action = call_allocate;
785 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
786 __FUNCTION__, status);
787 rpc_exit(task, -EIO);
792 * Even though there was an error, we may have acquired
793 * a request slot somehow. Make sure not to leak it.
795 if (task->tk_rqstp) {
796 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
797 __FUNCTION__, status);
802 case -EAGAIN: /* woken up; retry */
803 task->tk_action = call_reserve;
805 case -EIO: /* probably a shutdown */
808 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
809 __FUNCTION__, status);
812 rpc_exit(task, status);
816 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
817 * (Note: buffer memory is freed in xprt_release).
820 call_allocate(struct rpc_task *task)
822 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
823 struct rpc_rqst *req = task->tk_rqstp;
824 struct rpc_xprt *xprt = task->tk_xprt;
825 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
830 task->tk_action = call_bind;
835 if (proc->p_proc != 0) {
836 BUG_ON(proc->p_arglen == 0);
837 if (proc->p_decode != NULL)
838 BUG_ON(proc->p_replen == 0);
842 * Calculate the size (in quads) of the RPC call
843 * and reply headers, and convert both values
846 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
847 req->rq_callsize <<= 2;
848 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
849 req->rq_rcvsize <<= 2;
851 req->rq_buffer = xprt->ops->buf_alloc(task,
852 req->rq_callsize + req->rq_rcvsize);
853 if (req->rq_buffer != NULL)
856 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
858 if (RPC_IS_ASYNC(task) || !signalled()) {
859 task->tk_action = call_allocate;
860 rpc_delay(task, HZ>>4);
864 rpc_exit(task, -ERESTARTSYS);
868 rpc_task_need_encode(struct rpc_task *task)
870 return task->tk_rqstp->rq_snd_buf.len == 0;
874 rpc_task_force_reencode(struct rpc_task *task)
876 task->tk_rqstp->rq_snd_buf.len = 0;
880 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
882 buf->head[0].iov_base = start;
883 buf->head[0].iov_len = len;
884 buf->tail[0].iov_len = 0;
892 * 3. Encode arguments of an RPC call
895 call_encode(struct rpc_task *task)
897 struct rpc_rqst *req = task->tk_rqstp;
903 rpc_xdr_buf_init(&req->rq_snd_buf,
906 rpc_xdr_buf_init(&req->rq_rcv_buf,
907 (char *)req->rq_buffer + req->rq_callsize,
910 /* Encode header and provided arguments */
911 encode = task->tk_msg.rpc_proc->p_encode;
912 if (!(p = call_header(task))) {
913 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
914 rpc_exit(task, -EIO);
920 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
921 task->tk_msg.rpc_argp);
922 if (task->tk_status == -ENOMEM) {
923 /* XXX: Is this sane? */
924 rpc_delay(task, 3*HZ);
925 task->tk_status = -EAGAIN;
930 * 4. Get the server port number if not yet set
933 call_bind(struct rpc_task *task)
935 struct rpc_xprt *xprt = task->tk_xprt;
939 task->tk_action = call_connect;
940 if (!xprt_bound(xprt)) {
941 task->tk_action = call_bind_status;
942 task->tk_timeout = xprt->bind_timeout;
943 xprt->ops->rpcbind(task);
948 * 4a. Sort out bind result
951 call_bind_status(struct rpc_task *task)
955 if (task->tk_status >= 0) {
958 task->tk_action = call_connect;
962 switch (task->tk_status) {
964 dprintk("RPC: %5u rpcbind waiting for another request "
965 "to finish\n", task->tk_pid);
966 /* avoid busy-waiting here -- could be a network outage. */
967 rpc_delay(task, 5*HZ);
970 dprintk("RPC: %5u remote rpcbind: RPC program/version "
971 "unavailable\n", task->tk_pid);
972 /* fail immediately if this is an RPC ping */
973 if (task->tk_msg.rpc_proc->p_proc == 0) {
974 status = -EOPNOTSUPP;
977 rpc_delay(task, 3*HZ);
980 dprintk("RPC: %5u rpcbind request timed out\n",
984 /* server doesn't support any rpcbind version we know of */
985 dprintk("RPC: %5u remote rpcbind service unavailable\n",
988 case -EPROTONOSUPPORT:
989 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
992 task->tk_action = call_bind;
995 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
996 task->tk_pid, -task->tk_status);
999 rpc_exit(task, status);
1003 task->tk_action = call_timeout;
1007 * 4b. Connect to the RPC server
1010 call_connect(struct rpc_task *task)
1012 struct rpc_xprt *xprt = task->tk_xprt;
1014 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1016 (xprt_connected(xprt) ? "is" : "is not"));
1018 task->tk_action = call_transmit;
1019 if (!xprt_connected(xprt)) {
1020 task->tk_action = call_connect_status;
1021 if (task->tk_status < 0)
1028 * 4c. Sort out connect result
1031 call_connect_status(struct rpc_task *task)
1033 struct rpc_clnt *clnt = task->tk_client;
1034 int status = task->tk_status;
1036 dprint_status(task);
1038 task->tk_status = 0;
1040 clnt->cl_stats->netreconn++;
1041 task->tk_action = call_transmit;
1045 /* Something failed: remote service port may have changed */
1046 rpc_force_rebind(clnt);
1051 task->tk_action = call_bind;
1052 if (!RPC_IS_SOFT(task))
1054 /* if soft mounted, test if we've timed out */
1056 task->tk_action = call_timeout;
1059 rpc_exit(task, -EIO);
1063 * 5. Transmit the RPC request, and wait for reply
1066 call_transmit(struct rpc_task *task)
1068 dprint_status(task);
1070 task->tk_action = call_status;
1071 if (task->tk_status < 0)
1073 task->tk_status = xprt_prepare_transmit(task);
1074 if (task->tk_status != 0)
1076 task->tk_action = call_transmit_status;
1077 /* Encode here so that rpcsec_gss can use correct sequence number. */
1078 if (rpc_task_need_encode(task)) {
1079 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1081 /* Did the encode result in an error condition? */
1082 if (task->tk_status != 0)
1085 xprt_transmit(task);
1086 if (task->tk_status < 0)
1089 * On success, ensure that we call xprt_end_transmit() before sleeping
1090 * in order to allow access to the socket to other RPC requests.
1092 call_transmit_status(task);
1093 if (task->tk_msg.rpc_proc->p_decode != NULL)
1095 task->tk_action = rpc_exit_task;
1096 rpc_wake_up_task(task);
1100 * 5a. Handle cleanup after a transmission
1103 call_transmit_status(struct rpc_task *task)
1105 task->tk_action = call_status;
1107 * Special case: if we've been waiting on the socket's write_space()
1108 * callback, then don't call xprt_end_transmit().
1110 if (task->tk_status == -EAGAIN)
1112 xprt_end_transmit(task);
1113 rpc_task_force_reencode(task);
1117 * 6. Sort out the RPC call status
1120 call_status(struct rpc_task *task)
1122 struct rpc_clnt *clnt = task->tk_client;
1123 struct rpc_rqst *req = task->tk_rqstp;
1126 if (req->rq_received > 0 && !req->rq_bytes_sent)
1127 task->tk_status = req->rq_received;
1129 dprint_status(task);
1131 status = task->tk_status;
1133 task->tk_action = call_decode;
1137 task->tk_status = 0;
1143 * Delay any retries for 3 seconds, then handle as if it
1146 rpc_delay(task, 3*HZ);
1148 task->tk_action = call_timeout;
1149 if (task->tk_client->cl_discrtry)
1150 xprt_force_disconnect(task->tk_xprt);
1154 rpc_force_rebind(clnt);
1155 task->tk_action = call_bind;
1158 task->tk_action = call_transmit;
1161 /* shutdown or soft timeout */
1162 rpc_exit(task, status);
1165 printk("%s: RPC call returned error %d\n",
1166 clnt->cl_protname, -status);
1167 rpc_exit(task, status);
1172 * 6a. Handle RPC timeout
1173 * We do not release the request slot, so we keep using the
1174 * same XID for all retransmits.
1177 call_timeout(struct rpc_task *task)
1179 struct rpc_clnt *clnt = task->tk_client;
1181 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1182 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1186 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1187 task->tk_timeouts++;
1189 if (RPC_IS_SOFT(task)) {
1190 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1191 clnt->cl_protname, clnt->cl_server);
1192 rpc_exit(task, -EIO);
1196 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1197 task->tk_flags |= RPC_CALL_MAJORSEEN;
1198 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1199 clnt->cl_protname, clnt->cl_server);
1201 rpc_force_rebind(clnt);
1204 clnt->cl_stats->rpcretrans++;
1205 task->tk_action = call_bind;
1206 task->tk_status = 0;
1210 * 7. Decode the RPC reply
1213 call_decode(struct rpc_task *task)
1215 struct rpc_clnt *clnt = task->tk_client;
1216 struct rpc_rqst *req = task->tk_rqstp;
1217 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1220 dprintk("RPC: %5u call_decode (status %d)\n",
1221 task->tk_pid, task->tk_status);
1223 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1224 printk(KERN_NOTICE "%s: server %s OK\n",
1225 clnt->cl_protname, clnt->cl_server);
1226 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1229 if (task->tk_status < 12) {
1230 if (!RPC_IS_SOFT(task)) {
1231 task->tk_action = call_bind;
1232 clnt->cl_stats->rpcretrans++;
1235 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1236 clnt->cl_protname, task->tk_status);
1237 task->tk_action = call_timeout;
1242 * Ensure that we see all writes made by xprt_complete_rqst()
1243 * before it changed req->rq_received.
1246 req->rq_rcv_buf.len = req->rq_private_buf.len;
1248 /* Check that the softirq receive buffer is valid */
1249 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1250 sizeof(req->rq_rcv_buf)) != 0);
1252 /* Verify the RPC header */
1253 p = call_verify(task);
1255 if (p == ERR_PTR(-EAGAIN))
1260 task->tk_action = rpc_exit_task;
1263 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1264 task->tk_msg.rpc_resp);
1266 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1270 req->rq_received = req->rq_private_buf.len = 0;
1271 task->tk_status = 0;
1272 if (task->tk_client->cl_discrtry)
1273 xprt_force_disconnect(task->tk_xprt);
1277 * 8. Refresh the credentials if rejected by the server
1280 call_refresh(struct rpc_task *task)
1282 dprint_status(task);
1284 task->tk_action = call_refreshresult;
1285 task->tk_status = 0;
1286 task->tk_client->cl_stats->rpcauthrefresh++;
1287 rpcauth_refreshcred(task);
1291 * 8a. Process the results of a credential refresh
1294 call_refreshresult(struct rpc_task *task)
1296 int status = task->tk_status;
1298 dprint_status(task);
1300 task->tk_status = 0;
1301 task->tk_action = call_reserve;
1302 if (status >= 0 && rpcauth_uptodatecred(task))
1304 if (status == -EACCES) {
1305 rpc_exit(task, -EACCES);
1308 task->tk_action = call_refresh;
1309 if (status != -ETIMEDOUT)
1310 rpc_delay(task, 3*HZ);
1315 * Call header serialization
1318 call_header(struct rpc_task *task)
1320 struct rpc_clnt *clnt = task->tk_client;
1321 struct rpc_rqst *req = task->tk_rqstp;
1322 __be32 *p = req->rq_svec[0].iov_base;
1324 /* FIXME: check buffer size? */
1326 p = xprt_skip_transport_header(task->tk_xprt, p);
1327 *p++ = req->rq_xid; /* XID */
1328 *p++ = htonl(RPC_CALL); /* CALL */
1329 *p++ = htonl(RPC_VERSION); /* RPC version */
1330 *p++ = htonl(clnt->cl_prog); /* program number */
1331 *p++ = htonl(clnt->cl_vers); /* program version */
1332 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1333 p = rpcauth_marshcred(task, p);
1334 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1339 * Reply header verification
1342 call_verify(struct rpc_task *task)
1344 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1345 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1346 __be32 *p = iov->iov_base;
1348 int error = -EACCES;
1350 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1351 /* RFC-1014 says that the representation of XDR data must be a
1352 * multiple of four bytes
1353 * - if it isn't pointer subtraction in the NFS client may give
1356 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1357 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1358 task->tk_rqstp->rq_rcv_buf.len);
1363 p += 1; /* skip XID */
1365 if ((n = ntohl(*p++)) != RPC_REPLY) {
1366 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1367 task->tk_pid, __FUNCTION__, n);
1370 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1373 switch ((n = ntohl(*p++))) {
1374 case RPC_AUTH_ERROR:
1377 dprintk("RPC: %5u %s: RPC call version "
1379 task->tk_pid, __FUNCTION__);
1380 error = -EPROTONOSUPPORT;
1383 dprintk("RPC: %5u %s: RPC call rejected, "
1384 "unknown error: %x\n",
1385 task->tk_pid, __FUNCTION__, n);
1390 switch ((n = ntohl(*p++))) {
1391 case RPC_AUTH_REJECTEDCRED:
1392 case RPC_AUTH_REJECTEDVERF:
1393 case RPCSEC_GSS_CREDPROBLEM:
1394 case RPCSEC_GSS_CTXPROBLEM:
1395 if (!task->tk_cred_retry)
1397 task->tk_cred_retry--;
1398 dprintk("RPC: %5u %s: retry stale creds\n",
1399 task->tk_pid, __FUNCTION__);
1400 rpcauth_invalcred(task);
1401 /* Ensure we obtain a new XID! */
1403 task->tk_action = call_refresh;
1405 case RPC_AUTH_BADCRED:
1406 case RPC_AUTH_BADVERF:
1407 /* possibly garbled cred/verf? */
1408 if (!task->tk_garb_retry)
1410 task->tk_garb_retry--;
1411 dprintk("RPC: %5u %s: retry garbled creds\n",
1412 task->tk_pid, __FUNCTION__);
1413 task->tk_action = call_bind;
1415 case RPC_AUTH_TOOWEAK:
1416 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1417 "authentication.\n", task->tk_client->cl_server);
1420 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1421 task->tk_pid, __FUNCTION__, n);
1424 dprintk("RPC: %5u %s: call rejected %d\n",
1425 task->tk_pid, __FUNCTION__, n);
1428 if (!(p = rpcauth_checkverf(task, p))) {
1429 dprintk("RPC: %5u %s: auth check failed\n",
1430 task->tk_pid, __FUNCTION__);
1431 goto out_garbage; /* bad verifier, retry */
1433 len = p - (__be32 *)iov->iov_base - 1;
1436 switch ((n = ntohl(*p++))) {
1439 case RPC_PROG_UNAVAIL:
1440 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1441 task->tk_pid, __FUNCTION__,
1442 (unsigned int)task->tk_client->cl_prog,
1443 task->tk_client->cl_server);
1444 error = -EPFNOSUPPORT;
1446 case RPC_PROG_MISMATCH:
1447 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1448 "server %s\n", task->tk_pid, __FUNCTION__,
1449 (unsigned int)task->tk_client->cl_prog,
1450 (unsigned int)task->tk_client->cl_vers,
1451 task->tk_client->cl_server);
1452 error = -EPROTONOSUPPORT;
1454 case RPC_PROC_UNAVAIL:
1455 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1456 "version %u on server %s\n",
1457 task->tk_pid, __FUNCTION__,
1458 task->tk_msg.rpc_proc,
1459 task->tk_client->cl_prog,
1460 task->tk_client->cl_vers,
1461 task->tk_client->cl_server);
1462 error = -EOPNOTSUPP;
1464 case RPC_GARBAGE_ARGS:
1465 dprintk("RPC: %5u %s: server saw garbage\n",
1466 task->tk_pid, __FUNCTION__);
1469 dprintk("RPC: %5u %s: server accept status: %x\n",
1470 task->tk_pid, __FUNCTION__, n);
1475 task->tk_client->cl_stats->rpcgarbage++;
1476 if (task->tk_garb_retry) {
1477 task->tk_garb_retry--;
1478 dprintk("RPC: %5u %s: retrying\n",
1479 task->tk_pid, __FUNCTION__);
1480 task->tk_action = call_bind;
1482 return ERR_PTR(-EAGAIN);
1487 rpc_exit(task, error);
1488 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1489 __FUNCTION__, error);
1490 return ERR_PTR(error);
1492 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1497 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1502 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1507 static struct rpc_procinfo rpcproc_null = {
1508 .p_encode = rpcproc_encode_null,
1509 .p_decode = rpcproc_decode_null,
1512 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1514 struct rpc_message msg = {
1515 .rpc_proc = &rpcproc_null,
1518 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1519 err = rpc_call_sync(clnt, &msg, flags);
1520 put_rpccred(msg.rpc_cred);
1524 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1526 struct rpc_message msg = {
1527 .rpc_proc = &rpcproc_null,
1530 return rpc_do_run_task(clnt, &msg, flags, &rpc_default_ops, NULL);
1532 EXPORT_SYMBOL_GPL(rpc_call_null);
1535 void rpc_show_tasks(void)
1537 struct rpc_clnt *clnt;
1540 spin_lock(&rpc_client_lock);
1541 if (list_empty(&all_clients))
1543 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1544 "-rpcwait -action- ---ops--\n");
1545 list_for_each_entry(clnt, &all_clients, cl_clients) {
1546 if (list_empty(&clnt->cl_tasks))
1548 spin_lock(&clnt->cl_lock);
1549 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1550 const char *rpc_waitq = "none";
1553 if (t->tk_msg.rpc_proc)
1554 proc = t->tk_msg.rpc_proc->p_proc;
1558 if (RPC_IS_QUEUED(t))
1559 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1561 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1563 t->tk_flags, t->tk_status,
1565 (t->tk_client ? t->tk_client->cl_prog : 0),
1566 t->tk_rqstp, t->tk_timeout,
1568 t->tk_action, t->tk_ops);
1570 spin_unlock(&clnt->cl_lock);
1573 spin_unlock(&rpc_client_lock);