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)
47 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
50 static void call_start(struct rpc_task *task);
51 static void call_reserve(struct rpc_task *task);
52 static void call_reserveresult(struct rpc_task *task);
53 static void call_allocate(struct rpc_task *task);
54 static void call_encode(struct rpc_task *task);
55 static void call_decode(struct rpc_task *task);
56 static void call_bind(struct rpc_task *task);
57 static void call_bind_status(struct rpc_task *task);
58 static void call_transmit(struct rpc_task *task);
59 static void call_status(struct rpc_task *task);
60 static void call_transmit_status(struct rpc_task *task);
61 static void call_refresh(struct rpc_task *task);
62 static void call_refreshresult(struct rpc_task *task);
63 static void call_timeout(struct rpc_task *task);
64 static void call_connect(struct rpc_task *task);
65 static void call_connect_status(struct rpc_task *task);
66 static __be32 * call_header(struct rpc_task *task);
67 static __be32 * call_verify(struct rpc_task *task);
71 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
73 static uint32_t clntid;
76 clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
77 clnt->cl_dentry = ERR_PTR(-ENOENT);
81 clnt->cl_vfsmnt = rpc_get_mount();
82 if (IS_ERR(clnt->cl_vfsmnt))
83 return PTR_ERR(clnt->cl_vfsmnt);
86 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
87 "%s/clnt%x", dir_name,
88 (unsigned int)clntid++);
89 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
90 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
91 if (!IS_ERR(clnt->cl_dentry))
93 error = PTR_ERR(clnt->cl_dentry);
94 if (error != -EEXIST) {
95 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
96 clnt->cl_pathname, error);
103 static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor)
105 struct rpc_version *version;
106 struct rpc_clnt *clnt = NULL;
107 struct rpc_auth *auth;
111 dprintk("RPC: creating %s client for %s (xprt %p)\n",
112 program->name, servname, xprt);
117 if (vers >= program->nrvers || !(version = program->version[vers]))
121 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
124 clnt->cl_parent = clnt;
126 clnt->cl_server = clnt->cl_inline_name;
127 len = strlen(servname) + 1;
128 if (len > sizeof(clnt->cl_inline_name)) {
129 char *buf = kmalloc(len, GFP_KERNEL);
131 clnt->cl_server = buf;
133 len = sizeof(clnt->cl_inline_name);
135 strlcpy(clnt->cl_server, servname, len);
137 clnt->cl_xprt = xprt;
138 clnt->cl_procinfo = version->procs;
139 clnt->cl_maxproc = version->nrprocs;
140 clnt->cl_protname = program->name;
141 clnt->cl_prog = program->number;
142 clnt->cl_vers = version->number;
143 clnt->cl_stats = program->stats;
144 clnt->cl_metrics = rpc_alloc_iostats(clnt);
146 if (clnt->cl_metrics == NULL)
148 clnt->cl_program = program;
149 INIT_LIST_HEAD(&clnt->cl_tasks);
150 spin_lock_init(&clnt->cl_lock);
152 if (!xprt_bound(clnt->cl_xprt))
153 clnt->cl_autobind = 1;
155 clnt->cl_rtt = &clnt->cl_rtt_default;
156 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
158 kref_init(&clnt->cl_kref);
160 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
164 auth = rpcauth_create(flavor, clnt);
166 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
172 /* save the nodename */
173 clnt->cl_nodelen = strlen(utsname()->nodename);
174 if (clnt->cl_nodelen > UNX_MAXNODENAME)
175 clnt->cl_nodelen = UNX_MAXNODENAME;
176 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
177 rpc_register_client(clnt);
181 if (!IS_ERR(clnt->cl_dentry)) {
182 rpc_rmdir(clnt->cl_dentry);
186 rpc_free_iostats(clnt->cl_metrics);
188 if (clnt->cl_server != clnt->cl_inline_name)
189 kfree(clnt->cl_server);
198 * rpc_create - create an RPC client and transport with one call
199 * @args: rpc_clnt create argument structure
201 * Creates and initializes an RPC transport and an RPC client.
203 * It can ping the server in order to determine if it is up, and to see if
204 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
205 * this behavior so asynchronous tasks can also use rpc_create.
207 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
209 struct rpc_xprt *xprt;
210 struct rpc_clnt *clnt;
212 xprt = xprt_create_transport(args->protocol, args->address,
213 args->addrsize, args->timeout);
215 return (struct rpc_clnt *)xprt;
218 * By default, kernel RPC client connects from a reserved port.
219 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
220 * but it is always enabled for rpciod, which handles the connect
224 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
227 dprintk("RPC: creating %s client for %s (xprt %p)\n",
228 args->program->name, args->servername, xprt);
230 clnt = rpc_new_client(xprt, args->servername, args->program,
231 args->version, args->authflavor);
235 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
236 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
238 rpc_shutdown_client(clnt);
243 clnt->cl_softrtry = 1;
244 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
245 clnt->cl_softrtry = 0;
247 if (args->flags & RPC_CLNT_CREATE_INTR)
249 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
250 clnt->cl_autobind = 1;
251 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
252 clnt->cl_discrtry = 1;
256 EXPORT_SYMBOL_GPL(rpc_create);
259 * This function clones the RPC client structure. It allows us to share the
260 * same transport while varying parameters such as the authentication
264 rpc_clone_client(struct rpc_clnt *clnt)
266 struct rpc_clnt *new;
269 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
272 new->cl_parent = clnt;
273 /* Turn off autobind on clones */
274 new->cl_autobind = 0;
275 INIT_LIST_HEAD(&new->cl_tasks);
276 spin_lock_init(&new->cl_lock);
277 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
278 new->cl_metrics = rpc_alloc_iostats(clnt);
279 if (new->cl_metrics == NULL)
281 kref_init(&new->cl_kref);
282 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
286 atomic_inc(&new->cl_auth->au_count);
287 xprt_get(clnt->cl_xprt);
288 kref_get(&clnt->cl_kref);
289 rpc_register_client(new);
292 rpc_free_iostats(new->cl_metrics);
296 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
301 * Properly shut down an RPC client, terminating all outstanding
304 void rpc_shutdown_client(struct rpc_clnt *clnt)
306 dprintk("RPC: shutting down %s client for %s\n",
307 clnt->cl_protname, clnt->cl_server);
309 while (!list_empty(&clnt->cl_tasks)) {
310 rpc_killall_tasks(clnt);
311 wait_event_timeout(destroy_wait,
312 list_empty(&clnt->cl_tasks), 1*HZ);
315 rpc_release_client(clnt);
322 rpc_free_client(struct kref *kref)
324 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
326 dprintk("RPC: destroying %s client for %s\n",
327 clnt->cl_protname, clnt->cl_server);
329 rpcauth_destroy(clnt->cl_auth);
330 clnt->cl_auth = NULL;
332 if (!IS_ERR(clnt->cl_dentry)) {
333 rpc_rmdir(clnt->cl_dentry);
336 if (clnt->cl_parent != clnt) {
337 rpc_release_client(clnt->cl_parent);
340 if (clnt->cl_server != clnt->cl_inline_name)
341 kfree(clnt->cl_server);
343 rpc_unregister_client(clnt);
344 rpc_free_iostats(clnt->cl_metrics);
345 clnt->cl_metrics = NULL;
346 xprt_put(clnt->cl_xprt);
351 * Release reference to the RPC client
354 rpc_release_client(struct rpc_clnt *clnt)
356 dprintk("RPC: rpc_release_client(%p)\n", clnt);
358 if (list_empty(&clnt->cl_tasks))
359 wake_up(&destroy_wait);
360 kref_put(&clnt->cl_kref, rpc_free_client);
364 * rpc_bind_new_program - bind a new RPC program to an existing client
365 * @old - old rpc_client
366 * @program - rpc program to set
367 * @vers - rpc program version
369 * Clones the rpc client and sets up a new RPC program. This is mainly
370 * of use for enabling different RPC programs to share the same transport.
371 * The Sun NFSv2/v3 ACL protocol can do this.
373 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
374 struct rpc_program *program,
377 struct rpc_clnt *clnt;
378 struct rpc_version *version;
381 BUG_ON(vers >= program->nrvers || !program->version[vers]);
382 version = program->version[vers];
383 clnt = rpc_clone_client(old);
386 clnt->cl_procinfo = version->procs;
387 clnt->cl_maxproc = version->nrprocs;
388 clnt->cl_protname = program->name;
389 clnt->cl_prog = program->number;
390 clnt->cl_vers = version->number;
391 clnt->cl_stats = program->stats;
392 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
394 rpc_shutdown_client(clnt);
402 * Default callback for async RPC calls
405 rpc_default_callback(struct rpc_task *task, void *data)
409 static const struct rpc_call_ops rpc_default_ops = {
410 .rpc_call_done = rpc_default_callback,
414 * Export the signal mask handling for synchronous code that
415 * sleeps on RPC calls
417 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
419 static void rpc_save_sigmask(sigset_t *oldset, int intr)
421 unsigned long sigallow = sigmask(SIGKILL);
424 /* Block all signals except those listed in sigallow */
426 sigallow |= RPC_INTR_SIGNALS;
427 siginitsetinv(&sigmask, sigallow);
428 sigprocmask(SIG_BLOCK, &sigmask, oldset);
431 static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
433 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
436 static inline void rpc_restore_sigmask(sigset_t *oldset)
438 sigprocmask(SIG_SETMASK, oldset, NULL);
441 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
443 rpc_save_sigmask(oldset, clnt->cl_intr);
446 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
448 rpc_restore_sigmask(oldset);
452 * New rpc_call implementation
454 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
456 struct rpc_task *task;
460 BUG_ON(flags & RPC_TASK_ASYNC);
462 task = rpc_new_task(clnt, flags, &rpc_default_ops, NULL);
466 /* Mask signals on RPC calls _and_ GSS_AUTH upcalls */
467 rpc_task_sigmask(task, &oldset);
469 /* Set up the call info struct and execute the task */
470 rpc_call_setup(task, msg, 0);
471 if (task->tk_status == 0) {
472 atomic_inc(&task->tk_count);
475 status = task->tk_status;
477 rpc_restore_sigmask(&oldset);
482 * New rpc_call implementation
485 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
486 const struct rpc_call_ops *tk_ops, void *data)
488 struct rpc_task *task;
492 flags |= RPC_TASK_ASYNC;
494 /* Create/initialize a new RPC task */
496 if (!(task = rpc_new_task(clnt, flags, tk_ops, data)))
499 /* Mask signals on GSS_AUTH upcalls */
500 rpc_task_sigmask(task, &oldset);
502 rpc_call_setup(task, msg, 0);
504 /* Set up the call info struct and execute the task */
505 status = task->tk_status;
511 rpc_restore_sigmask(&oldset);
514 rpc_release_calldata(tk_ops, data);
520 rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
523 task->tk_flags |= flags;
524 /* Bind the user cred */
525 if (task->tk_msg.rpc_cred != NULL)
526 rpcauth_holdcred(task);
528 rpcauth_bindcred(task);
530 if (task->tk_status == 0)
531 task->tk_action = call_start;
533 task->tk_action = rpc_exit_task;
537 * rpc_peeraddr - extract remote peer address from clnt's xprt
538 * @clnt: RPC client structure
539 * @buf: target buffer
540 * @size: length of target buffer
542 * Returns the number of bytes that are actually in the stored address.
544 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
547 struct rpc_xprt *xprt = clnt->cl_xprt;
549 bytes = sizeof(xprt->addr);
552 memcpy(buf, &clnt->cl_xprt->addr, bytes);
553 return xprt->addrlen;
555 EXPORT_SYMBOL_GPL(rpc_peeraddr);
558 * rpc_peeraddr2str - return remote peer address in printable format
559 * @clnt: RPC client structure
560 * @format: address format
563 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
565 struct rpc_xprt *xprt = clnt->cl_xprt;
567 if (xprt->address_strings[format] != NULL)
568 return xprt->address_strings[format];
570 return "unprintable";
572 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
575 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
577 struct rpc_xprt *xprt = clnt->cl_xprt;
578 if (xprt->ops->set_buffer_size)
579 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
583 * Return size of largest payload RPC client can support, in bytes
585 * For stream transports, this is one RPC record fragment (see RFC
586 * 1831), as we don't support multi-record requests yet. For datagram
587 * transports, this is the size of an IP packet minus the IP, UDP, and
590 size_t rpc_max_payload(struct rpc_clnt *clnt)
592 return clnt->cl_xprt->max_payload;
594 EXPORT_SYMBOL_GPL(rpc_max_payload);
597 * rpc_force_rebind - force transport to check that remote port is unchanged
598 * @clnt: client to rebind
601 void rpc_force_rebind(struct rpc_clnt *clnt)
603 if (clnt->cl_autobind)
604 xprt_clear_bound(clnt->cl_xprt);
606 EXPORT_SYMBOL_GPL(rpc_force_rebind);
609 * Restart an (async) RPC call. Usually called from within the
613 rpc_restart_call(struct rpc_task *task)
615 if (RPC_ASSASSINATED(task))
618 task->tk_action = call_start;
624 * Other FSM states can be visited zero or more times, but
625 * this state is visited exactly once for each RPC.
628 call_start(struct rpc_task *task)
630 struct rpc_clnt *clnt = task->tk_client;
632 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
633 clnt->cl_protname, clnt->cl_vers,
634 task->tk_msg.rpc_proc->p_proc,
635 (RPC_IS_ASYNC(task) ? "async" : "sync"));
637 /* Increment call count */
638 task->tk_msg.rpc_proc->p_count++;
639 clnt->cl_stats->rpccnt++;
640 task->tk_action = call_reserve;
644 * 1. Reserve an RPC call slot
647 call_reserve(struct rpc_task *task)
651 if (!rpcauth_uptodatecred(task)) {
652 task->tk_action = call_refresh;
657 task->tk_action = call_reserveresult;
662 * 1b. Grok the result of xprt_reserve()
665 call_reserveresult(struct rpc_task *task)
667 int status = task->tk_status;
672 * After a call to xprt_reserve(), we must have either
673 * a request slot or else an error status.
677 if (task->tk_rqstp) {
678 task->tk_action = call_allocate;
682 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
683 __FUNCTION__, status);
684 rpc_exit(task, -EIO);
689 * Even though there was an error, we may have acquired
690 * a request slot somehow. Make sure not to leak it.
692 if (task->tk_rqstp) {
693 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
694 __FUNCTION__, status);
699 case -EAGAIN: /* woken up; retry */
700 task->tk_action = call_reserve;
702 case -EIO: /* probably a shutdown */
705 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
706 __FUNCTION__, status);
709 rpc_exit(task, status);
713 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
714 * (Note: buffer memory is freed in xprt_release).
717 call_allocate(struct rpc_task *task)
719 unsigned int slack = task->tk_auth->au_cslack;
720 struct rpc_rqst *req = task->tk_rqstp;
721 struct rpc_xprt *xprt = task->tk_xprt;
722 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
727 task->tk_action = call_bind;
732 if (proc->p_proc != 0) {
733 BUG_ON(proc->p_arglen == 0);
734 if (proc->p_decode != NULL)
735 BUG_ON(proc->p_replen == 0);
739 * Calculate the size (in quads) of the RPC call
740 * and reply headers, and convert both values
743 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
744 req->rq_callsize <<= 2;
745 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
746 req->rq_rcvsize <<= 2;
748 req->rq_buffer = xprt->ops->buf_alloc(task,
749 req->rq_callsize + req->rq_rcvsize);
750 if (req->rq_buffer != NULL)
753 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
755 if (RPC_IS_ASYNC(task) || !signalled()) {
757 task->tk_action = call_reserve;
758 rpc_delay(task, HZ>>4);
762 rpc_exit(task, -ERESTARTSYS);
766 rpc_task_need_encode(struct rpc_task *task)
768 return task->tk_rqstp->rq_snd_buf.len == 0;
772 rpc_task_force_reencode(struct rpc_task *task)
774 task->tk_rqstp->rq_snd_buf.len = 0;
778 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
780 buf->head[0].iov_base = start;
781 buf->head[0].iov_len = len;
782 buf->tail[0].iov_len = 0;
789 * 3. Encode arguments of an RPC call
792 call_encode(struct rpc_task *task)
794 struct rpc_rqst *req = task->tk_rqstp;
800 rpc_xdr_buf_init(&req->rq_snd_buf,
803 rpc_xdr_buf_init(&req->rq_rcv_buf,
804 (char *)req->rq_buffer + req->rq_callsize,
807 /* Encode header and provided arguments */
808 encode = task->tk_msg.rpc_proc->p_encode;
809 if (!(p = call_header(task))) {
810 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
811 rpc_exit(task, -EIO);
818 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
819 task->tk_msg.rpc_argp);
821 if (task->tk_status == -ENOMEM) {
822 /* XXX: Is this sane? */
823 rpc_delay(task, 3*HZ);
824 task->tk_status = -EAGAIN;
829 * 4. Get the server port number if not yet set
832 call_bind(struct rpc_task *task)
834 struct rpc_xprt *xprt = task->tk_xprt;
838 task->tk_action = call_connect;
839 if (!xprt_bound(xprt)) {
840 task->tk_action = call_bind_status;
841 task->tk_timeout = xprt->bind_timeout;
842 xprt->ops->rpcbind(task);
847 * 4a. Sort out bind result
850 call_bind_status(struct rpc_task *task)
852 int status = -EACCES;
854 if (task->tk_status >= 0) {
857 task->tk_action = call_connect;
861 switch (task->tk_status) {
863 dprintk("RPC: %5u remote rpcbind: RPC program/version "
864 "unavailable\n", task->tk_pid);
865 rpc_delay(task, 3*HZ);
868 dprintk("RPC: %5u rpcbind request timed out\n",
872 dprintk("RPC: %5u remote rpcbind service unavailable\n",
875 case -EPROTONOSUPPORT:
876 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
879 task->tk_action = call_bind;
882 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
883 task->tk_pid, -task->tk_status);
887 rpc_exit(task, status);
891 task->tk_action = call_timeout;
895 * 4b. Connect to the RPC server
898 call_connect(struct rpc_task *task)
900 struct rpc_xprt *xprt = task->tk_xprt;
902 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
904 (xprt_connected(xprt) ? "is" : "is not"));
906 task->tk_action = call_transmit;
907 if (!xprt_connected(xprt)) {
908 task->tk_action = call_connect_status;
909 if (task->tk_status < 0)
916 * 4c. Sort out connect result
919 call_connect_status(struct rpc_task *task)
921 struct rpc_clnt *clnt = task->tk_client;
922 int status = task->tk_status;
928 clnt->cl_stats->netreconn++;
929 task->tk_action = call_transmit;
933 /* Something failed: remote service port may have changed */
934 rpc_force_rebind(clnt);
939 task->tk_action = call_bind;
940 if (!RPC_IS_SOFT(task))
942 /* if soft mounted, test if we've timed out */
944 task->tk_action = call_timeout;
947 rpc_exit(task, -EIO);
951 * 5. Transmit the RPC request, and wait for reply
954 call_transmit(struct rpc_task *task)
958 task->tk_action = call_status;
959 if (task->tk_status < 0)
961 task->tk_status = xprt_prepare_transmit(task);
962 if (task->tk_status != 0)
964 task->tk_action = call_transmit_status;
965 /* Encode here so that rpcsec_gss can use correct sequence number. */
966 if (rpc_task_need_encode(task)) {
967 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
969 /* Did the encode result in an error condition? */
970 if (task->tk_status != 0)
974 if (task->tk_status < 0)
977 * On success, ensure that we call xprt_end_transmit() before sleeping
978 * in order to allow access to the socket to other RPC requests.
980 call_transmit_status(task);
981 if (task->tk_msg.rpc_proc->p_decode != NULL)
983 task->tk_action = rpc_exit_task;
984 rpc_wake_up_task(task);
988 * 5a. Handle cleanup after a transmission
991 call_transmit_status(struct rpc_task *task)
993 task->tk_action = call_status;
995 * Special case: if we've been waiting on the socket's write_space()
996 * callback, then don't call xprt_end_transmit().
998 if (task->tk_status == -EAGAIN)
1000 xprt_end_transmit(task);
1001 rpc_task_force_reencode(task);
1005 * 6. Sort out the RPC call status
1008 call_status(struct rpc_task *task)
1010 struct rpc_clnt *clnt = task->tk_client;
1011 struct rpc_rqst *req = task->tk_rqstp;
1014 if (req->rq_received > 0 && !req->rq_bytes_sent)
1015 task->tk_status = req->rq_received;
1017 dprint_status(task);
1019 status = task->tk_status;
1021 task->tk_action = call_decode;
1025 task->tk_status = 0;
1031 * Delay any retries for 3 seconds, then handle as if it
1034 rpc_delay(task, 3*HZ);
1036 task->tk_action = call_timeout;
1037 if (task->tk_client->cl_discrtry)
1038 xprt_disconnect(task->tk_xprt);
1042 rpc_force_rebind(clnt);
1043 task->tk_action = call_bind;
1046 task->tk_action = call_transmit;
1049 /* shutdown or soft timeout */
1050 rpc_exit(task, status);
1053 printk("%s: RPC call returned error %d\n",
1054 clnt->cl_protname, -status);
1055 rpc_exit(task, status);
1060 * 6a. Handle RPC timeout
1061 * We do not release the request slot, so we keep using the
1062 * same XID for all retransmits.
1065 call_timeout(struct rpc_task *task)
1067 struct rpc_clnt *clnt = task->tk_client;
1069 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1070 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1074 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1075 task->tk_timeouts++;
1077 if (RPC_IS_SOFT(task)) {
1078 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1079 clnt->cl_protname, clnt->cl_server);
1080 rpc_exit(task, -EIO);
1084 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1085 task->tk_flags |= RPC_CALL_MAJORSEEN;
1086 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1087 clnt->cl_protname, clnt->cl_server);
1089 rpc_force_rebind(clnt);
1092 clnt->cl_stats->rpcretrans++;
1093 task->tk_action = call_bind;
1094 task->tk_status = 0;
1098 * 7. Decode the RPC reply
1101 call_decode(struct rpc_task *task)
1103 struct rpc_clnt *clnt = task->tk_client;
1104 struct rpc_rqst *req = task->tk_rqstp;
1105 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1108 dprintk("RPC: %5u call_decode (status %d)\n",
1109 task->tk_pid, task->tk_status);
1111 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1112 printk(KERN_NOTICE "%s: server %s OK\n",
1113 clnt->cl_protname, clnt->cl_server);
1114 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1117 if (task->tk_status < 12) {
1118 if (!RPC_IS_SOFT(task)) {
1119 task->tk_action = call_bind;
1120 clnt->cl_stats->rpcretrans++;
1123 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1124 clnt->cl_protname, task->tk_status);
1125 task->tk_action = call_timeout;
1130 * Ensure that we see all writes made by xprt_complete_rqst()
1131 * before it changed req->rq_received.
1134 req->rq_rcv_buf.len = req->rq_private_buf.len;
1136 /* Check that the softirq receive buffer is valid */
1137 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1138 sizeof(req->rq_rcv_buf)) != 0);
1140 /* Verify the RPC header */
1141 p = call_verify(task);
1143 if (p == ERR_PTR(-EAGAIN))
1148 task->tk_action = rpc_exit_task;
1152 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1153 task->tk_msg.rpc_resp);
1156 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1160 req->rq_received = req->rq_private_buf.len = 0;
1161 task->tk_status = 0;
1162 if (task->tk_client->cl_discrtry)
1163 xprt_disconnect(task->tk_xprt);
1167 * 8. Refresh the credentials if rejected by the server
1170 call_refresh(struct rpc_task *task)
1172 dprint_status(task);
1174 xprt_release(task); /* Must do to obtain new XID */
1175 task->tk_action = call_refreshresult;
1176 task->tk_status = 0;
1177 task->tk_client->cl_stats->rpcauthrefresh++;
1178 rpcauth_refreshcred(task);
1182 * 8a. Process the results of a credential refresh
1185 call_refreshresult(struct rpc_task *task)
1187 int status = task->tk_status;
1189 dprint_status(task);
1191 task->tk_status = 0;
1192 task->tk_action = call_reserve;
1193 if (status >= 0 && rpcauth_uptodatecred(task))
1195 if (status == -EACCES) {
1196 rpc_exit(task, -EACCES);
1199 task->tk_action = call_refresh;
1200 if (status != -ETIMEDOUT)
1201 rpc_delay(task, 3*HZ);
1206 * Call header serialization
1209 call_header(struct rpc_task *task)
1211 struct rpc_clnt *clnt = task->tk_client;
1212 struct rpc_rqst *req = task->tk_rqstp;
1213 __be32 *p = req->rq_svec[0].iov_base;
1215 /* FIXME: check buffer size? */
1217 p = xprt_skip_transport_header(task->tk_xprt, p);
1218 *p++ = req->rq_xid; /* XID */
1219 *p++ = htonl(RPC_CALL); /* CALL */
1220 *p++ = htonl(RPC_VERSION); /* RPC version */
1221 *p++ = htonl(clnt->cl_prog); /* program number */
1222 *p++ = htonl(clnt->cl_vers); /* program version */
1223 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1224 p = rpcauth_marshcred(task, p);
1225 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1230 * Reply header verification
1233 call_verify(struct rpc_task *task)
1235 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1236 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1237 __be32 *p = iov->iov_base;
1239 int error = -EACCES;
1241 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1242 /* RFC-1014 says that the representation of XDR data must be a
1243 * multiple of four bytes
1244 * - if it isn't pointer subtraction in the NFS client may give
1248 "call_verify: XDR representation not a multiple of"
1249 " 4 bytes: 0x%x\n", task->tk_rqstp->rq_rcv_buf.len);
1254 p += 1; /* skip XID */
1256 if ((n = ntohl(*p++)) != RPC_REPLY) {
1257 printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n);
1260 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1263 switch ((n = ntohl(*p++))) {
1264 case RPC_AUTH_ERROR:
1267 dprintk("RPC: %5u %s: RPC call version "
1269 task->tk_pid, __FUNCTION__);
1270 error = -EPROTONOSUPPORT;
1273 dprintk("RPC: %5u %s: RPC call rejected, "
1274 "unknown error: %x\n",
1275 task->tk_pid, __FUNCTION__, n);
1280 switch ((n = ntohl(*p++))) {
1281 case RPC_AUTH_REJECTEDCRED:
1282 case RPC_AUTH_REJECTEDVERF:
1283 case RPCSEC_GSS_CREDPROBLEM:
1284 case RPCSEC_GSS_CTXPROBLEM:
1285 if (!task->tk_cred_retry)
1287 task->tk_cred_retry--;
1288 dprintk("RPC: %5u %s: retry stale creds\n",
1289 task->tk_pid, __FUNCTION__);
1290 rpcauth_invalcred(task);
1291 task->tk_action = call_refresh;
1293 case RPC_AUTH_BADCRED:
1294 case RPC_AUTH_BADVERF:
1295 /* possibly garbled cred/verf? */
1296 if (!task->tk_garb_retry)
1298 task->tk_garb_retry--;
1299 dprintk("RPC: %5u %s: retry garbled creds\n",
1300 task->tk_pid, __FUNCTION__);
1301 task->tk_action = call_bind;
1303 case RPC_AUTH_TOOWEAK:
1304 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1305 "authentication.\n", task->tk_client->cl_server);
1308 printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n);
1311 dprintk("RPC: %5u %s: call rejected %d\n",
1312 task->tk_pid, __FUNCTION__, n);
1315 if (!(p = rpcauth_checkverf(task, p))) {
1316 printk(KERN_WARNING "call_verify: auth check failed\n");
1317 goto out_garbage; /* bad verifier, retry */
1319 len = p - (__be32 *)iov->iov_base - 1;
1322 switch ((n = ntohl(*p++))) {
1325 case RPC_PROG_UNAVAIL:
1326 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1327 task->tk_pid, __FUNCTION__,
1328 (unsigned int)task->tk_client->cl_prog,
1329 task->tk_client->cl_server);
1330 error = -EPFNOSUPPORT;
1332 case RPC_PROG_MISMATCH:
1333 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1334 "server %s\n", task->tk_pid, __FUNCTION__,
1335 (unsigned int)task->tk_client->cl_prog,
1336 (unsigned int)task->tk_client->cl_vers,
1337 task->tk_client->cl_server);
1338 error = -EPROTONOSUPPORT;
1340 case RPC_PROC_UNAVAIL:
1341 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1342 "version %u on server %s\n",
1343 task->tk_pid, __FUNCTION__,
1344 task->tk_msg.rpc_proc,
1345 task->tk_client->cl_prog,
1346 task->tk_client->cl_vers,
1347 task->tk_client->cl_server);
1348 error = -EOPNOTSUPP;
1350 case RPC_GARBAGE_ARGS:
1351 dprintk("RPC: %5u %s: server saw garbage\n",
1352 task->tk_pid, __FUNCTION__);
1355 printk(KERN_WARNING "call_verify: server accept status: %x\n", n);
1360 task->tk_client->cl_stats->rpcgarbage++;
1361 if (task->tk_garb_retry) {
1362 task->tk_garb_retry--;
1363 dprintk("RPC: %5u %s: retrying\n",
1364 task->tk_pid, __FUNCTION__);
1365 task->tk_action = call_bind;
1367 return ERR_PTR(-EAGAIN);
1369 printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__);
1373 rpc_exit(task, error);
1374 return ERR_PTR(error);
1376 printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__);
1380 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1385 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1390 static struct rpc_procinfo rpcproc_null = {
1391 .p_encode = rpcproc_encode_null,
1392 .p_decode = rpcproc_decode_null,
1395 int rpc_ping(struct rpc_clnt *clnt, int flags)
1397 struct rpc_message msg = {
1398 .rpc_proc = &rpcproc_null,
1401 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1402 err = rpc_call_sync(clnt, &msg, flags);
1403 put_rpccred(msg.rpc_cred);