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 __func__, 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(const struct rpc_create_args *args, struct rpc_xprt *xprt)
127 struct rpc_program *program = args->program;
128 struct rpc_version *version;
129 struct rpc_clnt *clnt = NULL;
130 struct rpc_auth *auth;
134 /* sanity check the name before trying to print it */
136 len = strlen(args->servername);
137 if (len > RPC_MAXNETNAMELEN)
141 dprintk("RPC: creating %s client for %s (xprt %p)\n",
142 program->name, args->servername, xprt);
151 if (args->version >= program->nrvers)
153 version = program->version[args->version];
158 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
161 clnt->cl_parent = clnt;
163 clnt->cl_server = clnt->cl_inline_name;
164 if (len > sizeof(clnt->cl_inline_name)) {
165 char *buf = kmalloc(len, GFP_KERNEL);
167 clnt->cl_server = buf;
169 len = sizeof(clnt->cl_inline_name);
171 strlcpy(clnt->cl_server, args->servername, len);
173 clnt->cl_xprt = xprt;
174 clnt->cl_procinfo = version->procs;
175 clnt->cl_maxproc = version->nrprocs;
176 clnt->cl_protname = program->name;
177 clnt->cl_prog = program->number;
178 clnt->cl_vers = version->number;
179 clnt->cl_stats = program->stats;
180 clnt->cl_metrics = rpc_alloc_iostats(clnt);
182 if (clnt->cl_metrics == NULL)
184 clnt->cl_program = program;
185 INIT_LIST_HEAD(&clnt->cl_tasks);
186 spin_lock_init(&clnt->cl_lock);
188 if (!xprt_bound(clnt->cl_xprt))
189 clnt->cl_autobind = 1;
191 clnt->cl_timeout = xprt->timeout;
192 if (args->timeout != NULL) {
193 memcpy(&clnt->cl_timeout_default, args->timeout,
194 sizeof(clnt->cl_timeout_default));
195 clnt->cl_timeout = &clnt->cl_timeout_default;
198 clnt->cl_rtt = &clnt->cl_rtt_default;
199 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
201 kref_init(&clnt->cl_kref);
203 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
207 auth = rpcauth_create(args->authflavor, clnt);
209 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
215 /* save the nodename */
216 clnt->cl_nodelen = strlen(utsname()->nodename);
217 if (clnt->cl_nodelen > UNX_MAXNODENAME)
218 clnt->cl_nodelen = UNX_MAXNODENAME;
219 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
220 rpc_register_client(clnt);
224 if (!IS_ERR(clnt->cl_dentry)) {
225 rpc_rmdir(clnt->cl_dentry);
229 rpc_free_iostats(clnt->cl_metrics);
231 if (clnt->cl_server != clnt->cl_inline_name)
232 kfree(clnt->cl_server);
243 * rpc_create - create an RPC client and transport with one call
244 * @args: rpc_clnt create argument structure
246 * Creates and initializes an RPC transport and an RPC client.
248 * It can ping the server in order to determine if it is up, and to see if
249 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
250 * this behavior so asynchronous tasks can also use rpc_create.
252 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
254 struct rpc_xprt *xprt;
255 struct rpc_clnt *clnt;
256 struct xprt_create xprtargs = {
257 .ident = args->protocol,
258 .srcaddr = args->saddress,
259 .dstaddr = args->address,
260 .addrlen = args->addrsize,
265 * If the caller chooses not to specify a hostname, whip
266 * up a string representation of the passed-in address.
268 if (args->servername == NULL) {
269 servername[0] = '\0';
270 switch (args->address->sa_family) {
272 struct sockaddr_in *sin =
273 (struct sockaddr_in *)args->address;
274 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
275 NIPQUAD(sin->sin_addr.s_addr));
279 struct sockaddr_in6 *sin =
280 (struct sockaddr_in6 *)args->address;
281 snprintf(servername, sizeof(servername), NIP6_FMT,
282 NIP6(sin->sin6_addr));
286 /* caller wants default server name, but
287 * address family isn't recognized. */
288 return ERR_PTR(-EINVAL);
290 args->servername = servername;
293 xprt = xprt_create_transport(&xprtargs);
295 return (struct rpc_clnt *)xprt;
298 * By default, kernel RPC client connects from a reserved port.
299 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
300 * but it is always enabled for rpciod, which handles the connect
304 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
307 clnt = rpc_new_client(args, xprt);
311 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
312 int err = rpc_ping(clnt, RPC_TASK_SOFT);
314 rpc_shutdown_client(clnt);
319 clnt->cl_softrtry = 1;
320 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
321 clnt->cl_softrtry = 0;
323 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
324 clnt->cl_autobind = 1;
325 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
326 clnt->cl_discrtry = 1;
330 EXPORT_SYMBOL_GPL(rpc_create);
333 * This function clones the RPC client structure. It allows us to share the
334 * same transport while varying parameters such as the authentication
338 rpc_clone_client(struct rpc_clnt *clnt)
340 struct rpc_clnt *new;
343 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
346 new->cl_parent = clnt;
347 /* Turn off autobind on clones */
348 new->cl_autobind = 0;
349 INIT_LIST_HEAD(&new->cl_tasks);
350 spin_lock_init(&new->cl_lock);
351 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
352 new->cl_metrics = rpc_alloc_iostats(clnt);
353 if (new->cl_metrics == NULL)
355 kref_init(&new->cl_kref);
356 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
360 atomic_inc(&new->cl_auth->au_count);
361 xprt_get(clnt->cl_xprt);
362 kref_get(&clnt->cl_kref);
363 rpc_register_client(new);
367 rpc_free_iostats(new->cl_metrics);
371 dprintk("RPC: %s: returned error %d\n", __func__, err);
374 EXPORT_SYMBOL_GPL(rpc_clone_client);
377 * Properly shut down an RPC client, terminating all outstanding
380 void rpc_shutdown_client(struct rpc_clnt *clnt)
382 dprintk("RPC: shutting down %s client for %s\n",
383 clnt->cl_protname, clnt->cl_server);
385 while (!list_empty(&clnt->cl_tasks)) {
386 rpc_killall_tasks(clnt);
387 wait_event_timeout(destroy_wait,
388 list_empty(&clnt->cl_tasks), 1*HZ);
391 rpc_release_client(clnt);
393 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
399 rpc_free_client(struct kref *kref)
401 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
403 dprintk("RPC: destroying %s client for %s\n",
404 clnt->cl_protname, clnt->cl_server);
405 if (!IS_ERR(clnt->cl_dentry)) {
406 rpc_rmdir(clnt->cl_dentry);
409 if (clnt->cl_parent != clnt) {
410 rpc_release_client(clnt->cl_parent);
413 if (clnt->cl_server != clnt->cl_inline_name)
414 kfree(clnt->cl_server);
416 rpc_unregister_client(clnt);
417 rpc_free_iostats(clnt->cl_metrics);
418 clnt->cl_metrics = NULL;
419 xprt_put(clnt->cl_xprt);
428 rpc_free_auth(struct kref *kref)
430 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
432 if (clnt->cl_auth == NULL) {
433 rpc_free_client(kref);
438 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
439 * release remaining GSS contexts. This mechanism ensures
440 * that it can do so safely.
443 rpcauth_release(clnt->cl_auth);
444 clnt->cl_auth = NULL;
445 kref_put(kref, rpc_free_client);
449 * Release reference to the RPC client
452 rpc_release_client(struct rpc_clnt *clnt)
454 dprintk("RPC: rpc_release_client(%p)\n", clnt);
456 if (list_empty(&clnt->cl_tasks))
457 wake_up(&destroy_wait);
458 kref_put(&clnt->cl_kref, rpc_free_auth);
462 * rpc_bind_new_program - bind a new RPC program to an existing client
463 * @old: old rpc_client
464 * @program: rpc program to set
465 * @vers: rpc program version
467 * Clones the rpc client and sets up a new RPC program. This is mainly
468 * of use for enabling different RPC programs to share the same transport.
469 * The Sun NFSv2/v3 ACL protocol can do this.
471 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
472 struct rpc_program *program,
475 struct rpc_clnt *clnt;
476 struct rpc_version *version;
479 BUG_ON(vers >= program->nrvers || !program->version[vers]);
480 version = program->version[vers];
481 clnt = rpc_clone_client(old);
484 clnt->cl_procinfo = version->procs;
485 clnt->cl_maxproc = version->nrprocs;
486 clnt->cl_protname = program->name;
487 clnt->cl_prog = program->number;
488 clnt->cl_vers = version->number;
489 clnt->cl_stats = program->stats;
490 err = rpc_ping(clnt, RPC_TASK_SOFT);
492 rpc_shutdown_client(clnt);
498 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
501 * Default callback for async RPC calls
504 rpc_default_callback(struct rpc_task *task, void *data)
508 static const struct rpc_call_ops rpc_default_ops = {
509 .rpc_call_done = rpc_default_callback,
513 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
514 * @task_setup_data: pointer to task initialisation data
516 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
518 struct rpc_task *task, *ret;
520 task = rpc_new_task(task_setup_data);
522 rpc_release_calldata(task_setup_data->callback_ops,
523 task_setup_data->callback_data);
524 ret = ERR_PTR(-ENOMEM);
528 if (task->tk_status != 0) {
529 ret = ERR_PTR(task->tk_status);
533 atomic_inc(&task->tk_count);
539 EXPORT_SYMBOL_GPL(rpc_run_task);
542 * rpc_call_sync - Perform a synchronous RPC call
543 * @clnt: pointer to RPC client
544 * @msg: RPC call parameters
545 * @flags: RPC call flags
547 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
549 struct rpc_task *task;
550 struct rpc_task_setup task_setup_data = {
553 .callback_ops = &rpc_default_ops,
558 BUG_ON(flags & RPC_TASK_ASYNC);
560 task = rpc_run_task(&task_setup_data);
562 return PTR_ERR(task);
563 status = task->tk_status;
567 EXPORT_SYMBOL_GPL(rpc_call_sync);
570 * rpc_call_async - Perform an asynchronous RPC call
571 * @clnt: pointer to RPC client
572 * @msg: RPC call parameters
573 * @flags: RPC call flags
574 * @tk_ops: RPC call ops
575 * @data: user call data
578 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
579 const struct rpc_call_ops *tk_ops, void *data)
581 struct rpc_task *task;
582 struct rpc_task_setup task_setup_data = {
585 .callback_ops = tk_ops,
586 .callback_data = data,
587 .flags = flags|RPC_TASK_ASYNC,
590 task = rpc_run_task(&task_setup_data);
592 return PTR_ERR(task);
596 EXPORT_SYMBOL_GPL(rpc_call_async);
599 rpc_call_start(struct rpc_task *task)
601 task->tk_action = call_start;
603 EXPORT_SYMBOL_GPL(rpc_call_start);
606 * rpc_peeraddr - extract remote peer address from clnt's xprt
607 * @clnt: RPC client structure
608 * @buf: target buffer
609 * @bufsize: length of target buffer
611 * Returns the number of bytes that are actually in the stored address.
613 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
616 struct rpc_xprt *xprt = clnt->cl_xprt;
618 bytes = sizeof(xprt->addr);
621 memcpy(buf, &clnt->cl_xprt->addr, bytes);
622 return xprt->addrlen;
624 EXPORT_SYMBOL_GPL(rpc_peeraddr);
627 * rpc_peeraddr2str - return remote peer address in printable format
628 * @clnt: RPC client structure
629 * @format: address format
632 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
633 enum rpc_display_format_t format)
635 struct rpc_xprt *xprt = clnt->cl_xprt;
637 if (xprt->address_strings[format] != NULL)
638 return xprt->address_strings[format];
640 return "unprintable";
642 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
645 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
647 struct rpc_xprt *xprt = clnt->cl_xprt;
648 if (xprt->ops->set_buffer_size)
649 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
651 EXPORT_SYMBOL_GPL(rpc_setbufsize);
654 * Return size of largest payload RPC client can support, in bytes
656 * For stream transports, this is one RPC record fragment (see RFC
657 * 1831), as we don't support multi-record requests yet. For datagram
658 * transports, this is the size of an IP packet minus the IP, UDP, and
661 size_t rpc_max_payload(struct rpc_clnt *clnt)
663 return clnt->cl_xprt->max_payload;
665 EXPORT_SYMBOL_GPL(rpc_max_payload);
668 * rpc_force_rebind - force transport to check that remote port is unchanged
669 * @clnt: client to rebind
672 void rpc_force_rebind(struct rpc_clnt *clnt)
674 if (clnt->cl_autobind)
675 xprt_clear_bound(clnt->cl_xprt);
677 EXPORT_SYMBOL_GPL(rpc_force_rebind);
680 * Restart an (async) RPC call. Usually called from within the
684 rpc_restart_call(struct rpc_task *task)
686 if (RPC_ASSASSINATED(task))
689 task->tk_action = call_start;
691 EXPORT_SYMBOL_GPL(rpc_restart_call);
694 static const char *rpc_proc_name(const struct rpc_task *task)
696 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
711 * Other FSM states can be visited zero or more times, but
712 * this state is visited exactly once for each RPC.
715 call_start(struct rpc_task *task)
717 struct rpc_clnt *clnt = task->tk_client;
719 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
720 clnt->cl_protname, clnt->cl_vers,
722 (RPC_IS_ASYNC(task) ? "async" : "sync"));
724 /* Increment call count */
725 task->tk_msg.rpc_proc->p_count++;
726 clnt->cl_stats->rpccnt++;
727 task->tk_action = call_reserve;
731 * 1. Reserve an RPC call slot
734 call_reserve(struct rpc_task *task)
738 if (!rpcauth_uptodatecred(task)) {
739 task->tk_action = call_refresh;
744 task->tk_action = call_reserveresult;
749 * 1b. Grok the result of xprt_reserve()
752 call_reserveresult(struct rpc_task *task)
754 int status = task->tk_status;
759 * After a call to xprt_reserve(), we must have either
760 * a request slot or else an error status.
764 if (task->tk_rqstp) {
765 task->tk_action = call_allocate;
769 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
771 rpc_exit(task, -EIO);
776 * Even though there was an error, we may have acquired
777 * a request slot somehow. Make sure not to leak it.
779 if (task->tk_rqstp) {
780 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
786 case -EAGAIN: /* woken up; retry */
787 task->tk_action = call_reserve;
789 case -EIO: /* probably a shutdown */
792 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
796 rpc_exit(task, status);
800 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
801 * (Note: buffer memory is freed in xprt_release).
804 call_allocate(struct rpc_task *task)
806 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
807 struct rpc_rqst *req = task->tk_rqstp;
808 struct rpc_xprt *xprt = task->tk_xprt;
809 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
814 task->tk_action = call_bind;
819 if (proc->p_proc != 0) {
820 BUG_ON(proc->p_arglen == 0);
821 if (proc->p_decode != NULL)
822 BUG_ON(proc->p_replen == 0);
826 * Calculate the size (in quads) of the RPC call
827 * and reply headers, and convert both values
830 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
831 req->rq_callsize <<= 2;
832 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
833 req->rq_rcvsize <<= 2;
835 req->rq_buffer = xprt->ops->buf_alloc(task,
836 req->rq_callsize + req->rq_rcvsize);
837 if (req->rq_buffer != NULL)
840 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
842 if (RPC_IS_ASYNC(task) || !signalled()) {
843 task->tk_action = call_allocate;
844 rpc_delay(task, HZ>>4);
848 rpc_exit(task, -ERESTARTSYS);
852 rpc_task_need_encode(struct rpc_task *task)
854 return task->tk_rqstp->rq_snd_buf.len == 0;
858 rpc_task_force_reencode(struct rpc_task *task)
860 task->tk_rqstp->rq_snd_buf.len = 0;
864 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
866 buf->head[0].iov_base = start;
867 buf->head[0].iov_len = len;
868 buf->tail[0].iov_len = 0;
876 * 3. Encode arguments of an RPC call
879 call_encode(struct rpc_task *task)
881 struct rpc_rqst *req = task->tk_rqstp;
887 rpc_xdr_buf_init(&req->rq_snd_buf,
890 rpc_xdr_buf_init(&req->rq_rcv_buf,
891 (char *)req->rq_buffer + req->rq_callsize,
894 /* Encode header and provided arguments */
895 encode = task->tk_msg.rpc_proc->p_encode;
896 if (!(p = call_header(task))) {
897 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
898 rpc_exit(task, -EIO);
904 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
905 task->tk_msg.rpc_argp);
909 * 4. Get the server port number if not yet set
912 call_bind(struct rpc_task *task)
914 struct rpc_xprt *xprt = task->tk_xprt;
918 task->tk_action = call_connect;
919 if (!xprt_bound(xprt)) {
920 task->tk_action = call_bind_status;
921 task->tk_timeout = xprt->bind_timeout;
922 xprt->ops->rpcbind(task);
927 * 4a. Sort out bind result
930 call_bind_status(struct rpc_task *task)
934 if (task->tk_status >= 0) {
937 task->tk_action = call_connect;
941 switch (task->tk_status) {
943 dprintk("RPC: %5u rpcbind waiting for another request "
944 "to finish\n", task->tk_pid);
945 /* avoid busy-waiting here -- could be a network outage. */
946 rpc_delay(task, 5*HZ);
949 dprintk("RPC: %5u remote rpcbind: RPC program/version "
950 "unavailable\n", task->tk_pid);
951 /* fail immediately if this is an RPC ping */
952 if (task->tk_msg.rpc_proc->p_proc == 0) {
953 status = -EOPNOTSUPP;
956 rpc_delay(task, 3*HZ);
959 dprintk("RPC: %5u rpcbind request timed out\n",
963 /* server doesn't support any rpcbind version we know of */
964 dprintk("RPC: %5u remote rpcbind service unavailable\n",
967 case -EPROTONOSUPPORT:
968 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
971 task->tk_action = call_bind;
974 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
975 task->tk_pid, -task->tk_status);
978 rpc_exit(task, status);
982 task->tk_action = call_timeout;
986 * 4b. Connect to the RPC server
989 call_connect(struct rpc_task *task)
991 struct rpc_xprt *xprt = task->tk_xprt;
993 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
995 (xprt_connected(xprt) ? "is" : "is not"));
997 task->tk_action = call_transmit;
998 if (!xprt_connected(xprt)) {
999 task->tk_action = call_connect_status;
1000 if (task->tk_status < 0)
1007 * 4c. Sort out connect result
1010 call_connect_status(struct rpc_task *task)
1012 struct rpc_clnt *clnt = task->tk_client;
1013 int status = task->tk_status;
1015 dprint_status(task);
1017 task->tk_status = 0;
1019 clnt->cl_stats->netreconn++;
1020 task->tk_action = call_transmit;
1024 /* Something failed: remote service port may have changed */
1025 rpc_force_rebind(clnt);
1030 task->tk_action = call_bind;
1031 if (!RPC_IS_SOFT(task))
1033 /* if soft mounted, test if we've timed out */
1035 task->tk_action = call_timeout;
1038 rpc_exit(task, -EIO);
1042 * 5. Transmit the RPC request, and wait for reply
1045 call_transmit(struct rpc_task *task)
1047 dprint_status(task);
1049 task->tk_action = call_status;
1050 if (task->tk_status < 0)
1052 task->tk_status = xprt_prepare_transmit(task);
1053 if (task->tk_status != 0)
1055 task->tk_action = call_transmit_status;
1056 /* Encode here so that rpcsec_gss can use correct sequence number. */
1057 if (rpc_task_need_encode(task)) {
1058 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1060 /* Did the encode result in an error condition? */
1061 if (task->tk_status != 0) {
1062 /* Was the error nonfatal? */
1063 if (task->tk_status == -EAGAIN)
1064 rpc_delay(task, HZ >> 4);
1066 rpc_exit(task, task->tk_status);
1070 xprt_transmit(task);
1071 if (task->tk_status < 0)
1074 * On success, ensure that we call xprt_end_transmit() before sleeping
1075 * in order to allow access to the socket to other RPC requests.
1077 call_transmit_status(task);
1078 if (task->tk_msg.rpc_proc->p_decode != NULL)
1080 task->tk_action = rpc_exit_task;
1081 rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
1085 * 5a. Handle cleanup after a transmission
1088 call_transmit_status(struct rpc_task *task)
1090 task->tk_action = call_status;
1092 * Special case: if we've been waiting on the socket's write_space()
1093 * callback, then don't call xprt_end_transmit().
1095 if (task->tk_status == -EAGAIN)
1097 xprt_end_transmit(task);
1098 rpc_task_force_reencode(task);
1102 * 6. Sort out the RPC call status
1105 call_status(struct rpc_task *task)
1107 struct rpc_clnt *clnt = task->tk_client;
1108 struct rpc_rqst *req = task->tk_rqstp;
1111 if (req->rq_received > 0 && !req->rq_bytes_sent)
1112 task->tk_status = req->rq_received;
1114 dprint_status(task);
1116 status = task->tk_status;
1118 task->tk_action = call_decode;
1122 task->tk_status = 0;
1128 * Delay any retries for 3 seconds, then handle as if it
1131 rpc_delay(task, 3*HZ);
1133 task->tk_action = call_timeout;
1134 if (task->tk_client->cl_discrtry)
1135 xprt_conditional_disconnect(task->tk_xprt,
1136 req->rq_connect_cookie);
1140 rpc_force_rebind(clnt);
1141 task->tk_action = call_bind;
1144 task->tk_action = call_transmit;
1147 /* shutdown or soft timeout */
1148 rpc_exit(task, status);
1151 printk("%s: RPC call returned error %d\n",
1152 clnt->cl_protname, -status);
1153 rpc_exit(task, status);
1158 * 6a. Handle RPC timeout
1159 * We do not release the request slot, so we keep using the
1160 * same XID for all retransmits.
1163 call_timeout(struct rpc_task *task)
1165 struct rpc_clnt *clnt = task->tk_client;
1167 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1168 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1172 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1173 task->tk_timeouts++;
1175 if (RPC_IS_SOFT(task)) {
1176 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1177 clnt->cl_protname, clnt->cl_server);
1178 rpc_exit(task, -EIO);
1182 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1183 task->tk_flags |= RPC_CALL_MAJORSEEN;
1184 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1185 clnt->cl_protname, clnt->cl_server);
1187 rpc_force_rebind(clnt);
1189 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1190 * event? RFC2203 requires the server to drop all such requests.
1192 rpcauth_invalcred(task);
1195 clnt->cl_stats->rpcretrans++;
1196 task->tk_action = call_bind;
1197 task->tk_status = 0;
1201 * 7. Decode the RPC reply
1204 call_decode(struct rpc_task *task)
1206 struct rpc_clnt *clnt = task->tk_client;
1207 struct rpc_rqst *req = task->tk_rqstp;
1208 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1211 dprintk("RPC: %5u call_decode (status %d)\n",
1212 task->tk_pid, task->tk_status);
1214 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1215 printk(KERN_NOTICE "%s: server %s OK\n",
1216 clnt->cl_protname, clnt->cl_server);
1217 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1221 * Ensure that we see all writes made by xprt_complete_rqst()
1222 * before it changed req->rq_received.
1225 req->rq_rcv_buf.len = req->rq_private_buf.len;
1227 /* Check that the softirq receive buffer is valid */
1228 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1229 sizeof(req->rq_rcv_buf)) != 0);
1231 if (req->rq_rcv_buf.len < 12) {
1232 if (!RPC_IS_SOFT(task)) {
1233 task->tk_action = call_bind;
1234 clnt->cl_stats->rpcretrans++;
1237 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1238 clnt->cl_protname, task->tk_status);
1239 task->tk_action = call_timeout;
1243 /* Verify the RPC header */
1244 p = call_verify(task);
1246 if (p == ERR_PTR(-EAGAIN))
1251 task->tk_action = rpc_exit_task;
1254 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1255 task->tk_msg.rpc_resp);
1257 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1261 task->tk_status = 0;
1262 /* Note: call_verify() may have freed the RPC slot */
1263 if (task->tk_rqstp == req) {
1264 req->rq_received = req->rq_rcv_buf.len = 0;
1265 if (task->tk_client->cl_discrtry)
1266 xprt_conditional_disconnect(task->tk_xprt,
1267 req->rq_connect_cookie);
1272 * 8. Refresh the credentials if rejected by the server
1275 call_refresh(struct rpc_task *task)
1277 dprint_status(task);
1279 task->tk_action = call_refreshresult;
1280 task->tk_status = 0;
1281 task->tk_client->cl_stats->rpcauthrefresh++;
1282 rpcauth_refreshcred(task);
1286 * 8a. Process the results of a credential refresh
1289 call_refreshresult(struct rpc_task *task)
1291 int status = task->tk_status;
1293 dprint_status(task);
1295 task->tk_status = 0;
1296 task->tk_action = call_reserve;
1297 if (status >= 0 && rpcauth_uptodatecred(task))
1299 if (status == -EACCES) {
1300 rpc_exit(task, -EACCES);
1303 task->tk_action = call_refresh;
1304 if (status != -ETIMEDOUT)
1305 rpc_delay(task, 3*HZ);
1310 * Call header serialization
1313 call_header(struct rpc_task *task)
1315 struct rpc_clnt *clnt = task->tk_client;
1316 struct rpc_rqst *req = task->tk_rqstp;
1317 __be32 *p = req->rq_svec[0].iov_base;
1319 /* FIXME: check buffer size? */
1321 p = xprt_skip_transport_header(task->tk_xprt, p);
1322 *p++ = req->rq_xid; /* XID */
1323 *p++ = htonl(RPC_CALL); /* CALL */
1324 *p++ = htonl(RPC_VERSION); /* RPC version */
1325 *p++ = htonl(clnt->cl_prog); /* program number */
1326 *p++ = htonl(clnt->cl_vers); /* program version */
1327 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1328 p = rpcauth_marshcred(task, p);
1329 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1334 * Reply header verification
1337 call_verify(struct rpc_task *task)
1339 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1340 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1341 __be32 *p = iov->iov_base;
1343 int error = -EACCES;
1345 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1346 /* RFC-1014 says that the representation of XDR data must be a
1347 * multiple of four bytes
1348 * - if it isn't pointer subtraction in the NFS client may give
1351 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1352 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
1353 task->tk_rqstp->rq_rcv_buf.len);
1358 p += 1; /* skip XID */
1360 if ((n = ntohl(*p++)) != RPC_REPLY) {
1361 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1362 task->tk_pid, __func__, n);
1365 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1368 switch ((n = ntohl(*p++))) {
1369 case RPC_AUTH_ERROR:
1372 dprintk("RPC: %5u %s: RPC call version "
1374 task->tk_pid, __func__);
1375 error = -EPROTONOSUPPORT;
1378 dprintk("RPC: %5u %s: RPC call rejected, "
1379 "unknown error: %x\n",
1380 task->tk_pid, __func__, n);
1385 switch ((n = ntohl(*p++))) {
1386 case RPC_AUTH_REJECTEDCRED:
1387 case RPC_AUTH_REJECTEDVERF:
1388 case RPCSEC_GSS_CREDPROBLEM:
1389 case RPCSEC_GSS_CTXPROBLEM:
1390 if (!task->tk_cred_retry)
1392 task->tk_cred_retry--;
1393 dprintk("RPC: %5u %s: retry stale creds\n",
1394 task->tk_pid, __func__);
1395 rpcauth_invalcred(task);
1396 /* Ensure we obtain a new XID! */
1398 task->tk_action = call_refresh;
1400 case RPC_AUTH_BADCRED:
1401 case RPC_AUTH_BADVERF:
1402 /* possibly garbled cred/verf? */
1403 if (!task->tk_garb_retry)
1405 task->tk_garb_retry--;
1406 dprintk("RPC: %5u %s: retry garbled creds\n",
1407 task->tk_pid, __func__);
1408 task->tk_action = call_bind;
1410 case RPC_AUTH_TOOWEAK:
1411 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1412 "authentication.\n", task->tk_client->cl_server);
1415 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1416 task->tk_pid, __func__, n);
1419 dprintk("RPC: %5u %s: call rejected %d\n",
1420 task->tk_pid, __func__, n);
1423 if (!(p = rpcauth_checkverf(task, p))) {
1424 dprintk("RPC: %5u %s: auth check failed\n",
1425 task->tk_pid, __func__);
1426 goto out_garbage; /* bad verifier, retry */
1428 len = p - (__be32 *)iov->iov_base - 1;
1431 switch ((n = ntohl(*p++))) {
1434 case RPC_PROG_UNAVAIL:
1435 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1436 task->tk_pid, __func__,
1437 (unsigned int)task->tk_client->cl_prog,
1438 task->tk_client->cl_server);
1439 error = -EPFNOSUPPORT;
1441 case RPC_PROG_MISMATCH:
1442 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1443 "server %s\n", task->tk_pid, __func__,
1444 (unsigned int)task->tk_client->cl_prog,
1445 (unsigned int)task->tk_client->cl_vers,
1446 task->tk_client->cl_server);
1447 error = -EPROTONOSUPPORT;
1449 case RPC_PROC_UNAVAIL:
1450 dprintk("RPC: %5u %s: proc %s unsupported by program %u, "
1451 "version %u on server %s\n",
1452 task->tk_pid, __func__,
1453 rpc_proc_name(task),
1454 task->tk_client->cl_prog,
1455 task->tk_client->cl_vers,
1456 task->tk_client->cl_server);
1457 error = -EOPNOTSUPP;
1459 case RPC_GARBAGE_ARGS:
1460 dprintk("RPC: %5u %s: server saw garbage\n",
1461 task->tk_pid, __func__);
1464 dprintk("RPC: %5u %s: server accept status: %x\n",
1465 task->tk_pid, __func__, n);
1470 task->tk_client->cl_stats->rpcgarbage++;
1471 if (task->tk_garb_retry) {
1472 task->tk_garb_retry--;
1473 dprintk("RPC: %5u %s: retrying\n",
1474 task->tk_pid, __func__);
1475 task->tk_action = call_bind;
1477 return ERR_PTR(-EAGAIN);
1482 rpc_exit(task, error);
1483 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1485 return ERR_PTR(error);
1487 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1492 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1497 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1502 static struct rpc_procinfo rpcproc_null = {
1503 .p_encode = rpcproc_encode_null,
1504 .p_decode = rpcproc_decode_null,
1507 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1509 struct rpc_message msg = {
1510 .rpc_proc = &rpcproc_null,
1513 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1514 err = rpc_call_sync(clnt, &msg, flags);
1515 put_rpccred(msg.rpc_cred);
1519 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1521 struct rpc_message msg = {
1522 .rpc_proc = &rpcproc_null,
1525 struct rpc_task_setup task_setup_data = {
1527 .rpc_message = &msg,
1528 .callback_ops = &rpc_default_ops,
1531 return rpc_run_task(&task_setup_data);
1533 EXPORT_SYMBOL_GPL(rpc_call_null);
1536 void rpc_show_tasks(void)
1538 struct rpc_clnt *clnt;
1541 spin_lock(&rpc_client_lock);
1542 if (list_empty(&all_clients))
1544 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1545 "-rpcwait -action- ---ops--\n");
1546 list_for_each_entry(clnt, &all_clients, cl_clients) {
1547 if (list_empty(&clnt->cl_tasks))
1549 spin_lock(&clnt->cl_lock);
1550 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1551 const char *rpc_waitq = "none";
1554 if (t->tk_msg.rpc_proc)
1555 proc = t->tk_msg.rpc_proc->p_proc;
1559 if (RPC_IS_QUEUED(t))
1560 rpc_waitq = rpc_qname(t->tk_waitqueue);
1562 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1564 t->tk_flags, t->tk_status,
1566 (t->tk_client ? t->tk_client->cl_prog : 0),
1567 t->tk_rqstp, t->tk_timeout,
1569 t->tk_action, t->tk_ops);
1571 spin_unlock(&clnt->cl_lock);
1574 spin_unlock(&rpc_client_lock);