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>
28 #include <linux/kallsyms.h>
30 #include <linux/namei.h>
31 #include <linux/mount.h>
32 #include <linux/slab.h>
33 #include <linux/utsname.h>
34 #include <linux/workqueue.h>
35 #include <linux/in6.h>
37 #include <linux/sunrpc/clnt.h>
38 #include <linux/sunrpc/rpc_pipe_fs.h>
39 #include <linux/sunrpc/metrics.h>
40 #include <linux/sunrpc/bc_xprt.h>
45 # define RPCDBG_FACILITY RPCDBG_CALL
48 #define dprint_status(t) \
49 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
50 __func__, t->tk_status)
53 * All RPC clients are linked into this list
55 static LIST_HEAD(all_clients);
56 static DEFINE_SPINLOCK(rpc_client_lock);
58 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
61 static void call_start(struct rpc_task *task);
62 static void call_reserve(struct rpc_task *task);
63 static void call_reserveresult(struct rpc_task *task);
64 static void call_allocate(struct rpc_task *task);
65 static void call_decode(struct rpc_task *task);
66 static void call_bind(struct rpc_task *task);
67 static void call_bind_status(struct rpc_task *task);
68 static void call_transmit(struct rpc_task *task);
69 #if defined(CONFIG_NFS_V4_1)
70 static void call_bc_transmit(struct rpc_task *task);
71 #endif /* CONFIG_NFS_V4_1 */
72 static void call_status(struct rpc_task *task);
73 static void call_transmit_status(struct rpc_task *task);
74 static void call_refresh(struct rpc_task *task);
75 static void call_refreshresult(struct rpc_task *task);
76 static void call_timeout(struct rpc_task *task);
77 static void call_connect(struct rpc_task *task);
78 static void call_connect_status(struct rpc_task *task);
80 static __be32 *rpc_encode_header(struct rpc_task *task);
81 static __be32 *rpc_verify_header(struct rpc_task *task);
82 static int rpc_ping(struct rpc_clnt *clnt, int flags);
84 static void rpc_register_client(struct rpc_clnt *clnt)
86 spin_lock(&rpc_client_lock);
87 list_add(&clnt->cl_clients, &all_clients);
88 spin_unlock(&rpc_client_lock);
91 static void rpc_unregister_client(struct rpc_clnt *clnt)
93 spin_lock(&rpc_client_lock);
94 list_del(&clnt->cl_clients);
95 spin_unlock(&rpc_client_lock);
99 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
101 static uint32_t clntid;
110 clnt->cl_path.mnt = ERR_PTR(-ENOENT);
111 clnt->cl_path.dentry = ERR_PTR(-ENOENT);
112 if (dir_name == NULL)
115 path.mnt = rpc_get_mount();
116 if (IS_ERR(path.mnt))
117 return PTR_ERR(path.mnt);
118 error = vfs_path_lookup(path.mnt->mnt_root, path.mnt, dir_name, 0, &nd);
123 q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
124 name[sizeof(name) - 1] = '\0';
125 q.hash = full_name_hash(q.name, q.len);
126 path.dentry = rpc_create_client_dir(nd.path.dentry, &q, clnt);
127 if (!IS_ERR(path.dentry))
129 error = PTR_ERR(path.dentry);
130 if (error != -EEXIST) {
131 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
132 " %s/%s, error %d\n",
133 dir_name, name, error);
138 clnt->cl_path = path;
147 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
149 struct rpc_program *program = args->program;
150 struct rpc_version *version;
151 struct rpc_clnt *clnt = NULL;
152 struct rpc_auth *auth;
156 /* sanity check the name before trying to print it */
158 len = strlen(args->servername);
159 if (len > RPC_MAXNETNAMELEN)
163 dprintk("RPC: creating %s client for %s (xprt %p)\n",
164 program->name, args->servername, xprt);
173 if (args->version >= program->nrvers)
175 version = program->version[args->version];
180 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
183 clnt->cl_parent = clnt;
185 clnt->cl_server = clnt->cl_inline_name;
186 if (len > sizeof(clnt->cl_inline_name)) {
187 char *buf = kmalloc(len, GFP_KERNEL);
189 clnt->cl_server = buf;
191 len = sizeof(clnt->cl_inline_name);
193 strlcpy(clnt->cl_server, args->servername, len);
195 clnt->cl_xprt = xprt;
196 clnt->cl_procinfo = version->procs;
197 clnt->cl_maxproc = version->nrprocs;
198 clnt->cl_protname = program->name;
199 clnt->cl_prog = args->prognumber ? : program->number;
200 clnt->cl_vers = version->number;
201 clnt->cl_stats = program->stats;
202 clnt->cl_metrics = rpc_alloc_iostats(clnt);
204 if (clnt->cl_metrics == NULL)
206 clnt->cl_program = program;
207 INIT_LIST_HEAD(&clnt->cl_tasks);
208 spin_lock_init(&clnt->cl_lock);
210 if (!xprt_bound(clnt->cl_xprt))
211 clnt->cl_autobind = 1;
213 clnt->cl_timeout = xprt->timeout;
214 if (args->timeout != NULL) {
215 memcpy(&clnt->cl_timeout_default, args->timeout,
216 sizeof(clnt->cl_timeout_default));
217 clnt->cl_timeout = &clnt->cl_timeout_default;
220 clnt->cl_rtt = &clnt->cl_rtt_default;
221 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
222 clnt->cl_principal = NULL;
223 if (args->client_name) {
224 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL);
225 if (!clnt->cl_principal)
226 goto out_no_principal;
229 kref_init(&clnt->cl_kref);
231 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
235 auth = rpcauth_create(args->authflavor, clnt);
237 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
243 /* save the nodename */
244 clnt->cl_nodelen = strlen(init_utsname()->nodename);
245 if (clnt->cl_nodelen > UNX_MAXNODENAME)
246 clnt->cl_nodelen = UNX_MAXNODENAME;
247 memcpy(clnt->cl_nodename, init_utsname()->nodename, clnt->cl_nodelen);
248 rpc_register_client(clnt);
252 if (!IS_ERR(clnt->cl_path.dentry)) {
253 rpc_remove_client_dir(clnt->cl_path.dentry);
257 kfree(clnt->cl_principal);
259 rpc_free_iostats(clnt->cl_metrics);
261 if (clnt->cl_server != clnt->cl_inline_name)
262 kfree(clnt->cl_server);
273 * rpc_create - create an RPC client and transport with one call
274 * @args: rpc_clnt create argument structure
276 * Creates and initializes an RPC transport and an RPC client.
278 * It can ping the server in order to determine if it is up, and to see if
279 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
280 * this behavior so asynchronous tasks can also use rpc_create.
282 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
284 struct rpc_xprt *xprt;
285 struct rpc_clnt *clnt;
286 struct xprt_create xprtargs = {
287 .ident = args->protocol,
288 .srcaddr = args->saddress,
289 .dstaddr = args->address,
290 .addrlen = args->addrsize,
291 .bc_xprt = args->bc_xprt,
296 * If the caller chooses not to specify a hostname, whip
297 * up a string representation of the passed-in address.
299 if (args->servername == NULL) {
300 servername[0] = '\0';
301 switch (args->address->sa_family) {
303 struct sockaddr_in *sin =
304 (struct sockaddr_in *)args->address;
305 snprintf(servername, sizeof(servername), "%pI4",
306 &sin->sin_addr.s_addr);
310 struct sockaddr_in6 *sin =
311 (struct sockaddr_in6 *)args->address;
312 snprintf(servername, sizeof(servername), "%pI6",
317 /* caller wants default server name, but
318 * address family isn't recognized. */
319 return ERR_PTR(-EINVAL);
321 args->servername = servername;
324 xprt = xprt_create_transport(&xprtargs);
326 return (struct rpc_clnt *)xprt;
329 * By default, kernel RPC client connects from a reserved port.
330 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
331 * but it is always enabled for rpciod, which handles the connect
335 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
338 clnt = rpc_new_client(args, xprt);
342 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
343 int err = rpc_ping(clnt, RPC_TASK_SOFT);
345 rpc_shutdown_client(clnt);
350 clnt->cl_softrtry = 1;
351 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
352 clnt->cl_softrtry = 0;
354 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
355 clnt->cl_autobind = 1;
356 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
357 clnt->cl_discrtry = 1;
358 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
363 EXPORT_SYMBOL_GPL(rpc_create);
366 * This function clones the RPC client structure. It allows us to share the
367 * same transport while varying parameters such as the authentication
371 rpc_clone_client(struct rpc_clnt *clnt)
373 struct rpc_clnt *new;
376 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
379 new->cl_parent = clnt;
380 /* Turn off autobind on clones */
381 new->cl_autobind = 0;
382 INIT_LIST_HEAD(&new->cl_tasks);
383 spin_lock_init(&new->cl_lock);
384 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
385 new->cl_metrics = rpc_alloc_iostats(clnt);
386 if (new->cl_metrics == NULL)
388 if (clnt->cl_principal) {
389 new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL);
390 if (new->cl_principal == NULL)
391 goto out_no_principal;
393 kref_init(&new->cl_kref);
394 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
398 atomic_inc(&new->cl_auth->au_count);
399 xprt_get(clnt->cl_xprt);
400 kref_get(&clnt->cl_kref);
401 rpc_register_client(new);
405 kfree(new->cl_principal);
407 rpc_free_iostats(new->cl_metrics);
411 dprintk("RPC: %s: returned error %d\n", __func__, err);
414 EXPORT_SYMBOL_GPL(rpc_clone_client);
417 * Properly shut down an RPC client, terminating all outstanding
420 void rpc_shutdown_client(struct rpc_clnt *clnt)
422 dprintk("RPC: shutting down %s client for %s\n",
423 clnt->cl_protname, clnt->cl_server);
425 while (!list_empty(&clnt->cl_tasks)) {
426 rpc_killall_tasks(clnt);
427 wait_event_timeout(destroy_wait,
428 list_empty(&clnt->cl_tasks), 1*HZ);
431 rpc_release_client(clnt);
433 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
439 rpc_free_client(struct kref *kref)
441 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
443 dprintk("RPC: destroying %s client for %s\n",
444 clnt->cl_protname, clnt->cl_server);
445 if (!IS_ERR(clnt->cl_path.dentry)) {
446 rpc_remove_client_dir(clnt->cl_path.dentry);
449 if (clnt->cl_parent != clnt) {
450 rpc_release_client(clnt->cl_parent);
453 if (clnt->cl_server != clnt->cl_inline_name)
454 kfree(clnt->cl_server);
456 rpc_unregister_client(clnt);
457 rpc_free_iostats(clnt->cl_metrics);
458 kfree(clnt->cl_principal);
459 clnt->cl_metrics = NULL;
460 xprt_put(clnt->cl_xprt);
469 rpc_free_auth(struct kref *kref)
471 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
473 if (clnt->cl_auth == NULL) {
474 rpc_free_client(kref);
479 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
480 * release remaining GSS contexts. This mechanism ensures
481 * that it can do so safely.
484 rpcauth_release(clnt->cl_auth);
485 clnt->cl_auth = NULL;
486 kref_put(kref, rpc_free_client);
490 * Release reference to the RPC client
493 rpc_release_client(struct rpc_clnt *clnt)
495 dprintk("RPC: rpc_release_client(%p)\n", clnt);
497 if (list_empty(&clnt->cl_tasks))
498 wake_up(&destroy_wait);
499 kref_put(&clnt->cl_kref, rpc_free_auth);
503 * rpc_bind_new_program - bind a new RPC program to an existing client
504 * @old: old rpc_client
505 * @program: rpc program to set
506 * @vers: rpc program version
508 * Clones the rpc client and sets up a new RPC program. This is mainly
509 * of use for enabling different RPC programs to share the same transport.
510 * The Sun NFSv2/v3 ACL protocol can do this.
512 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
513 struct rpc_program *program,
516 struct rpc_clnt *clnt;
517 struct rpc_version *version;
520 BUG_ON(vers >= program->nrvers || !program->version[vers]);
521 version = program->version[vers];
522 clnt = rpc_clone_client(old);
525 clnt->cl_procinfo = version->procs;
526 clnt->cl_maxproc = version->nrprocs;
527 clnt->cl_protname = program->name;
528 clnt->cl_prog = program->number;
529 clnt->cl_vers = version->number;
530 clnt->cl_stats = program->stats;
531 err = rpc_ping(clnt, RPC_TASK_SOFT);
533 rpc_shutdown_client(clnt);
539 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
542 * Default callback for async RPC calls
545 rpc_default_callback(struct rpc_task *task, void *data)
549 static const struct rpc_call_ops rpc_default_ops = {
550 .rpc_call_done = rpc_default_callback,
554 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
555 * @task_setup_data: pointer to task initialisation data
557 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
559 struct rpc_task *task, *ret;
561 task = rpc_new_task(task_setup_data);
563 rpc_release_calldata(task_setup_data->callback_ops,
564 task_setup_data->callback_data);
565 ret = ERR_PTR(-ENOMEM);
569 if (task->tk_status != 0) {
570 ret = ERR_PTR(task->tk_status);
574 atomic_inc(&task->tk_count);
580 EXPORT_SYMBOL_GPL(rpc_run_task);
583 * rpc_call_sync - Perform a synchronous RPC call
584 * @clnt: pointer to RPC client
585 * @msg: RPC call parameters
586 * @flags: RPC call flags
588 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
590 struct rpc_task *task;
591 struct rpc_task_setup task_setup_data = {
594 .callback_ops = &rpc_default_ops,
599 BUG_ON(flags & RPC_TASK_ASYNC);
601 task = rpc_run_task(&task_setup_data);
603 return PTR_ERR(task);
604 status = task->tk_status;
608 EXPORT_SYMBOL_GPL(rpc_call_sync);
611 * rpc_call_async - Perform an asynchronous RPC call
612 * @clnt: pointer to RPC client
613 * @msg: RPC call parameters
614 * @flags: RPC call flags
615 * @tk_ops: RPC call ops
616 * @data: user call data
619 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
620 const struct rpc_call_ops *tk_ops, void *data)
622 struct rpc_task *task;
623 struct rpc_task_setup task_setup_data = {
626 .callback_ops = tk_ops,
627 .callback_data = data,
628 .flags = flags|RPC_TASK_ASYNC,
631 task = rpc_run_task(&task_setup_data);
633 return PTR_ERR(task);
637 EXPORT_SYMBOL_GPL(rpc_call_async);
639 #if defined(CONFIG_NFS_V4_1)
641 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
642 * rpc_execute against it
645 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
646 const struct rpc_call_ops *tk_ops)
648 struct rpc_task *task;
649 struct xdr_buf *xbufp = &req->rq_snd_buf;
650 struct rpc_task_setup task_setup_data = {
651 .callback_ops = tk_ops,
654 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
656 * Create an rpc_task to send the data
658 task = rpc_new_task(&task_setup_data);
660 xprt_free_bc_request(req);
663 task->tk_rqstp = req;
666 * Set up the xdr_buf length.
667 * This also indicates that the buffer is XDR encoded already.
669 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
670 xbufp->tail[0].iov_len;
672 task->tk_action = call_bc_transmit;
673 atomic_inc(&task->tk_count);
674 BUG_ON(atomic_read(&task->tk_count) != 2);
678 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
681 #endif /* CONFIG_NFS_V4_1 */
684 rpc_call_start(struct rpc_task *task)
686 task->tk_action = call_start;
688 EXPORT_SYMBOL_GPL(rpc_call_start);
691 * rpc_peeraddr - extract remote peer address from clnt's xprt
692 * @clnt: RPC client structure
693 * @buf: target buffer
694 * @bufsize: length of target buffer
696 * Returns the number of bytes that are actually in the stored address.
698 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
701 struct rpc_xprt *xprt = clnt->cl_xprt;
703 bytes = sizeof(xprt->addr);
706 memcpy(buf, &clnt->cl_xprt->addr, bytes);
707 return xprt->addrlen;
709 EXPORT_SYMBOL_GPL(rpc_peeraddr);
712 * rpc_peeraddr2str - return remote peer address in printable format
713 * @clnt: RPC client structure
714 * @format: address format
717 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
718 enum rpc_display_format_t format)
720 struct rpc_xprt *xprt = clnt->cl_xprt;
722 if (xprt->address_strings[format] != NULL)
723 return xprt->address_strings[format];
725 return "unprintable";
727 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
730 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
732 struct rpc_xprt *xprt = clnt->cl_xprt;
733 if (xprt->ops->set_buffer_size)
734 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
736 EXPORT_SYMBOL_GPL(rpc_setbufsize);
739 * Return size of largest payload RPC client can support, in bytes
741 * For stream transports, this is one RPC record fragment (see RFC
742 * 1831), as we don't support multi-record requests yet. For datagram
743 * transports, this is the size of an IP packet minus the IP, UDP, and
746 size_t rpc_max_payload(struct rpc_clnt *clnt)
748 return clnt->cl_xprt->max_payload;
750 EXPORT_SYMBOL_GPL(rpc_max_payload);
753 * rpc_force_rebind - force transport to check that remote port is unchanged
754 * @clnt: client to rebind
757 void rpc_force_rebind(struct rpc_clnt *clnt)
759 if (clnt->cl_autobind)
760 xprt_clear_bound(clnt->cl_xprt);
762 EXPORT_SYMBOL_GPL(rpc_force_rebind);
765 * Restart an (async) RPC call from the call_prepare state.
766 * Usually called from within the exit handler.
769 rpc_restart_call_prepare(struct rpc_task *task)
771 if (RPC_ASSASSINATED(task))
773 task->tk_action = rpc_prepare_task;
775 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
778 * Restart an (async) RPC call. Usually called from within the
782 rpc_restart_call(struct rpc_task *task)
784 if (RPC_ASSASSINATED(task))
787 task->tk_action = call_start;
789 EXPORT_SYMBOL_GPL(rpc_restart_call);
792 static const char *rpc_proc_name(const struct rpc_task *task)
794 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
809 * Other FSM states can be visited zero or more times, but
810 * this state is visited exactly once for each RPC.
813 call_start(struct rpc_task *task)
815 struct rpc_clnt *clnt = task->tk_client;
817 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
818 clnt->cl_protname, clnt->cl_vers,
820 (RPC_IS_ASYNC(task) ? "async" : "sync"));
822 /* Increment call count */
823 task->tk_msg.rpc_proc->p_count++;
824 clnt->cl_stats->rpccnt++;
825 task->tk_action = call_reserve;
829 * 1. Reserve an RPC call slot
832 call_reserve(struct rpc_task *task)
836 if (!rpcauth_uptodatecred(task)) {
837 task->tk_action = call_refresh;
842 task->tk_action = call_reserveresult;
847 * 1b. Grok the result of xprt_reserve()
850 call_reserveresult(struct rpc_task *task)
852 int status = task->tk_status;
857 * After a call to xprt_reserve(), we must have either
858 * a request slot or else an error status.
862 if (task->tk_rqstp) {
863 task->tk_action = call_allocate;
867 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
869 rpc_exit(task, -EIO);
874 * Even though there was an error, we may have acquired
875 * a request slot somehow. Make sure not to leak it.
877 if (task->tk_rqstp) {
878 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
884 case -EAGAIN: /* woken up; retry */
885 task->tk_action = call_reserve;
887 case -EIO: /* probably a shutdown */
890 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
894 rpc_exit(task, status);
898 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
899 * (Note: buffer memory is freed in xprt_release).
902 call_allocate(struct rpc_task *task)
904 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
905 struct rpc_rqst *req = task->tk_rqstp;
906 struct rpc_xprt *xprt = task->tk_xprt;
907 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
912 task->tk_action = call_bind;
917 if (proc->p_proc != 0) {
918 BUG_ON(proc->p_arglen == 0);
919 if (proc->p_decode != NULL)
920 BUG_ON(proc->p_replen == 0);
924 * Calculate the size (in quads) of the RPC call
925 * and reply headers, and convert both values
928 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
929 req->rq_callsize <<= 2;
930 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
931 req->rq_rcvsize <<= 2;
933 req->rq_buffer = xprt->ops->buf_alloc(task,
934 req->rq_callsize + req->rq_rcvsize);
935 if (req->rq_buffer != NULL)
938 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
940 if (RPC_IS_ASYNC(task) || !signalled()) {
941 task->tk_action = call_allocate;
942 rpc_delay(task, HZ>>4);
946 rpc_exit(task, -ERESTARTSYS);
950 rpc_task_need_encode(struct rpc_task *task)
952 return task->tk_rqstp->rq_snd_buf.len == 0;
956 rpc_task_force_reencode(struct rpc_task *task)
958 task->tk_rqstp->rq_snd_buf.len = 0;
959 task->tk_rqstp->rq_bytes_sent = 0;
963 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
965 buf->head[0].iov_base = start;
966 buf->head[0].iov_len = len;
967 buf->tail[0].iov_len = 0;
975 * 3. Encode arguments of an RPC call
978 rpc_xdr_encode(struct rpc_task *task)
980 struct rpc_rqst *req = task->tk_rqstp;
986 rpc_xdr_buf_init(&req->rq_snd_buf,
989 rpc_xdr_buf_init(&req->rq_rcv_buf,
990 (char *)req->rq_buffer + req->rq_callsize,
993 p = rpc_encode_header(task);
995 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
996 rpc_exit(task, -EIO);
1000 encode = task->tk_msg.rpc_proc->p_encode;
1004 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1005 task->tk_msg.rpc_argp);
1009 * 4. Get the server port number if not yet set
1012 call_bind(struct rpc_task *task)
1014 struct rpc_xprt *xprt = task->tk_xprt;
1016 dprint_status(task);
1018 task->tk_action = call_connect;
1019 if (!xprt_bound(xprt)) {
1020 task->tk_action = call_bind_status;
1021 task->tk_timeout = xprt->bind_timeout;
1022 xprt->ops->rpcbind(task);
1027 * 4a. Sort out bind result
1030 call_bind_status(struct rpc_task *task)
1034 if (task->tk_status >= 0) {
1035 dprint_status(task);
1036 task->tk_status = 0;
1037 task->tk_action = call_connect;
1041 switch (task->tk_status) {
1043 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1044 rpc_delay(task, HZ >> 2);
1047 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1048 "unavailable\n", task->tk_pid);
1049 /* fail immediately if this is an RPC ping */
1050 if (task->tk_msg.rpc_proc->p_proc == 0) {
1051 status = -EOPNOTSUPP;
1054 rpc_delay(task, 3*HZ);
1057 dprintk("RPC: %5u rpcbind request timed out\n",
1061 /* server doesn't support any rpcbind version we know of */
1062 dprintk("RPC: %5u remote rpcbind service unavailable\n",
1065 case -EPROTONOSUPPORT:
1066 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1068 task->tk_status = 0;
1069 task->tk_action = call_bind;
1072 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1073 task->tk_pid, -task->tk_status);
1076 rpc_exit(task, status);
1080 task->tk_action = call_timeout;
1084 * 4b. Connect to the RPC server
1087 call_connect(struct rpc_task *task)
1089 struct rpc_xprt *xprt = task->tk_xprt;
1091 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1093 (xprt_connected(xprt) ? "is" : "is not"));
1095 task->tk_action = call_transmit;
1096 if (!xprt_connected(xprt)) {
1097 task->tk_action = call_connect_status;
1098 if (task->tk_status < 0)
1105 * 4c. Sort out connect result
1108 call_connect_status(struct rpc_task *task)
1110 struct rpc_clnt *clnt = task->tk_client;
1111 int status = task->tk_status;
1113 dprint_status(task);
1115 task->tk_status = 0;
1116 if (status >= 0 || status == -EAGAIN) {
1117 clnt->cl_stats->netreconn++;
1118 task->tk_action = call_transmit;
1123 /* if soft mounted, test if we've timed out */
1125 task->tk_action = call_timeout;
1128 rpc_exit(task, -EIO);
1133 * 5. Transmit the RPC request, and wait for reply
1136 call_transmit(struct rpc_task *task)
1138 dprint_status(task);
1140 task->tk_action = call_status;
1141 if (task->tk_status < 0)
1143 task->tk_status = xprt_prepare_transmit(task);
1144 if (task->tk_status != 0)
1146 task->tk_action = call_transmit_status;
1147 /* Encode here so that rpcsec_gss can use correct sequence number. */
1148 if (rpc_task_need_encode(task)) {
1149 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1150 rpc_xdr_encode(task);
1151 /* Did the encode result in an error condition? */
1152 if (task->tk_status != 0) {
1153 /* Was the error nonfatal? */
1154 if (task->tk_status == -EAGAIN)
1155 rpc_delay(task, HZ >> 4);
1157 rpc_exit(task, task->tk_status);
1161 xprt_transmit(task);
1162 if (task->tk_status < 0)
1165 * On success, ensure that we call xprt_end_transmit() before sleeping
1166 * in order to allow access to the socket to other RPC requests.
1168 call_transmit_status(task);
1169 if (rpc_reply_expected(task))
1171 task->tk_action = rpc_exit_task;
1172 rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
1176 * 5a. Handle cleanup after a transmission
1179 call_transmit_status(struct rpc_task *task)
1181 task->tk_action = call_status;
1182 switch (task->tk_status) {
1186 xprt_end_transmit(task);
1188 * Special cases: if we've been waiting on the
1189 * socket's write_space() callback, or if the
1190 * socket just returned a connection error,
1191 * then hold onto the transport lock.
1200 rpc_task_force_reencode(task);
1204 #if defined(CONFIG_NFS_V4_1)
1206 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1207 * addition, disconnect on connectivity errors.
1210 call_bc_transmit(struct rpc_task *task)
1212 struct rpc_rqst *req = task->tk_rqstp;
1214 BUG_ON(task->tk_status != 0);
1215 task->tk_status = xprt_prepare_transmit(task);
1216 if (task->tk_status == -EAGAIN) {
1218 * Could not reserve the transport. Try again after the
1219 * transport is released.
1221 task->tk_status = 0;
1222 task->tk_action = call_bc_transmit;
1226 task->tk_action = rpc_exit_task;
1227 if (task->tk_status < 0) {
1228 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1229 "error: %d\n", task->tk_status);
1233 xprt_transmit(task);
1234 xprt_end_transmit(task);
1235 dprint_status(task);
1236 switch (task->tk_status) {
1245 * Problem reaching the server. Disconnect and let the
1246 * forechannel reestablish the connection. The server will
1247 * have to retransmit the backchannel request and we'll
1248 * reprocess it. Since these ops are idempotent, there's no
1249 * need to cache our reply at this time.
1251 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1252 "error: %d\n", task->tk_status);
1253 xprt_conditional_disconnect(task->tk_xprt,
1254 req->rq_connect_cookie);
1258 * We were unable to reply and will have to drop the
1259 * request. The server should reconnect and retransmit.
1261 BUG_ON(task->tk_status == -EAGAIN);
1262 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1263 "error: %d\n", task->tk_status);
1266 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1268 #endif /* CONFIG_NFS_V4_1 */
1271 * 6. Sort out the RPC call status
1274 call_status(struct rpc_task *task)
1276 struct rpc_clnt *clnt = task->tk_client;
1277 struct rpc_rqst *req = task->tk_rqstp;
1280 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1281 task->tk_status = req->rq_reply_bytes_recvd;
1283 dprint_status(task);
1285 status = task->tk_status;
1287 task->tk_action = call_decode;
1291 task->tk_status = 0;
1297 * Delay any retries for 3 seconds, then handle as if it
1300 rpc_delay(task, 3*HZ);
1302 task->tk_action = call_timeout;
1303 if (task->tk_client->cl_discrtry)
1304 xprt_conditional_disconnect(task->tk_xprt,
1305 req->rq_connect_cookie);
1309 rpc_force_rebind(clnt);
1310 rpc_delay(task, 3*HZ);
1313 task->tk_action = call_bind;
1316 task->tk_action = call_transmit;
1319 /* shutdown or soft timeout */
1320 rpc_exit(task, status);
1323 if (clnt->cl_chatty)
1324 printk("%s: RPC call returned error %d\n",
1325 clnt->cl_protname, -status);
1326 rpc_exit(task, status);
1331 * 6a. Handle RPC timeout
1332 * We do not release the request slot, so we keep using the
1333 * same XID for all retransmits.
1336 call_timeout(struct rpc_task *task)
1338 struct rpc_clnt *clnt = task->tk_client;
1340 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1341 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1345 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1346 task->tk_timeouts++;
1348 if (RPC_IS_SOFT(task)) {
1349 if (clnt->cl_chatty)
1350 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1351 clnt->cl_protname, clnt->cl_server);
1352 rpc_exit(task, -EIO);
1356 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1357 task->tk_flags |= RPC_CALL_MAJORSEEN;
1358 if (clnt->cl_chatty)
1359 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1360 clnt->cl_protname, clnt->cl_server);
1362 rpc_force_rebind(clnt);
1364 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1365 * event? RFC2203 requires the server to drop all such requests.
1367 rpcauth_invalcred(task);
1370 clnt->cl_stats->rpcretrans++;
1371 task->tk_action = call_bind;
1372 task->tk_status = 0;
1376 * 7. Decode the RPC reply
1379 call_decode(struct rpc_task *task)
1381 struct rpc_clnt *clnt = task->tk_client;
1382 struct rpc_rqst *req = task->tk_rqstp;
1383 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1386 dprintk("RPC: %5u call_decode (status %d)\n",
1387 task->tk_pid, task->tk_status);
1389 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1390 if (clnt->cl_chatty)
1391 printk(KERN_NOTICE "%s: server %s OK\n",
1392 clnt->cl_protname, clnt->cl_server);
1393 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1397 * Ensure that we see all writes made by xprt_complete_rqst()
1398 * before it changed req->rq_reply_bytes_recvd.
1401 req->rq_rcv_buf.len = req->rq_private_buf.len;
1403 /* Check that the softirq receive buffer is valid */
1404 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1405 sizeof(req->rq_rcv_buf)) != 0);
1407 if (req->rq_rcv_buf.len < 12) {
1408 if (!RPC_IS_SOFT(task)) {
1409 task->tk_action = call_bind;
1410 clnt->cl_stats->rpcretrans++;
1413 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1414 clnt->cl_protname, task->tk_status);
1415 task->tk_action = call_timeout;
1419 p = rpc_verify_header(task);
1421 if (p == ERR_PTR(-EAGAIN))
1426 task->tk_action = rpc_exit_task;
1429 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1430 task->tk_msg.rpc_resp);
1432 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1436 task->tk_status = 0;
1437 /* Note: rpc_verify_header() may have freed the RPC slot */
1438 if (task->tk_rqstp == req) {
1439 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
1440 if (task->tk_client->cl_discrtry)
1441 xprt_conditional_disconnect(task->tk_xprt,
1442 req->rq_connect_cookie);
1447 * 8. Refresh the credentials if rejected by the server
1450 call_refresh(struct rpc_task *task)
1452 dprint_status(task);
1454 task->tk_action = call_refreshresult;
1455 task->tk_status = 0;
1456 task->tk_client->cl_stats->rpcauthrefresh++;
1457 rpcauth_refreshcred(task);
1461 * 8a. Process the results of a credential refresh
1464 call_refreshresult(struct rpc_task *task)
1466 int status = task->tk_status;
1468 dprint_status(task);
1470 task->tk_status = 0;
1471 task->tk_action = call_reserve;
1472 if (status >= 0 && rpcauth_uptodatecred(task))
1474 if (status == -EACCES) {
1475 rpc_exit(task, -EACCES);
1478 task->tk_action = call_refresh;
1479 if (status != -ETIMEDOUT)
1480 rpc_delay(task, 3*HZ);
1485 rpc_encode_header(struct rpc_task *task)
1487 struct rpc_clnt *clnt = task->tk_client;
1488 struct rpc_rqst *req = task->tk_rqstp;
1489 __be32 *p = req->rq_svec[0].iov_base;
1491 /* FIXME: check buffer size? */
1493 p = xprt_skip_transport_header(task->tk_xprt, p);
1494 *p++ = req->rq_xid; /* XID */
1495 *p++ = htonl(RPC_CALL); /* CALL */
1496 *p++ = htonl(RPC_VERSION); /* RPC version */
1497 *p++ = htonl(clnt->cl_prog); /* program number */
1498 *p++ = htonl(clnt->cl_vers); /* program version */
1499 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1500 p = rpcauth_marshcred(task, p);
1501 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1506 rpc_verify_header(struct rpc_task *task)
1508 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1509 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1510 __be32 *p = iov->iov_base;
1512 int error = -EACCES;
1514 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1515 /* RFC-1014 says that the representation of XDR data must be a
1516 * multiple of four bytes
1517 * - if it isn't pointer subtraction in the NFS client may give
1520 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1521 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
1522 task->tk_rqstp->rq_rcv_buf.len);
1528 p += 1; /* skip XID */
1529 if ((n = ntohl(*p++)) != RPC_REPLY) {
1530 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1531 task->tk_pid, __func__, n);
1535 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1538 switch ((n = ntohl(*p++))) {
1539 case RPC_AUTH_ERROR:
1542 dprintk("RPC: %5u %s: RPC call version "
1544 task->tk_pid, __func__);
1545 error = -EPROTONOSUPPORT;
1548 dprintk("RPC: %5u %s: RPC call rejected, "
1549 "unknown error: %x\n",
1550 task->tk_pid, __func__, n);
1555 switch ((n = ntohl(*p++))) {
1556 case RPC_AUTH_REJECTEDCRED:
1557 case RPC_AUTH_REJECTEDVERF:
1558 case RPCSEC_GSS_CREDPROBLEM:
1559 case RPCSEC_GSS_CTXPROBLEM:
1560 if (!task->tk_cred_retry)
1562 task->tk_cred_retry--;
1563 dprintk("RPC: %5u %s: retry stale creds\n",
1564 task->tk_pid, __func__);
1565 rpcauth_invalcred(task);
1566 /* Ensure we obtain a new XID! */
1568 task->tk_action = call_refresh;
1570 case RPC_AUTH_BADCRED:
1571 case RPC_AUTH_BADVERF:
1572 /* possibly garbled cred/verf? */
1573 if (!task->tk_garb_retry)
1575 task->tk_garb_retry--;
1576 dprintk("RPC: %5u %s: retry garbled creds\n",
1577 task->tk_pid, __func__);
1578 task->tk_action = call_bind;
1580 case RPC_AUTH_TOOWEAK:
1581 printk(KERN_NOTICE "RPC: server %s requires stronger "
1582 "authentication.\n", task->tk_client->cl_server);
1585 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1586 task->tk_pid, __func__, n);
1589 dprintk("RPC: %5u %s: call rejected %d\n",
1590 task->tk_pid, __func__, n);
1593 if (!(p = rpcauth_checkverf(task, p))) {
1594 dprintk("RPC: %5u %s: auth check failed\n",
1595 task->tk_pid, __func__);
1596 goto out_garbage; /* bad verifier, retry */
1598 len = p - (__be32 *)iov->iov_base - 1;
1601 switch ((n = ntohl(*p++))) {
1604 case RPC_PROG_UNAVAIL:
1605 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1606 task->tk_pid, __func__,
1607 (unsigned int)task->tk_client->cl_prog,
1608 task->tk_client->cl_server);
1609 error = -EPFNOSUPPORT;
1611 case RPC_PROG_MISMATCH:
1612 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1613 "server %s\n", task->tk_pid, __func__,
1614 (unsigned int)task->tk_client->cl_prog,
1615 (unsigned int)task->tk_client->cl_vers,
1616 task->tk_client->cl_server);
1617 error = -EPROTONOSUPPORT;
1619 case RPC_PROC_UNAVAIL:
1620 dprintk("RPC: %5u %s: proc %s unsupported by program %u, "
1621 "version %u on server %s\n",
1622 task->tk_pid, __func__,
1623 rpc_proc_name(task),
1624 task->tk_client->cl_prog,
1625 task->tk_client->cl_vers,
1626 task->tk_client->cl_server);
1627 error = -EOPNOTSUPP;
1629 case RPC_GARBAGE_ARGS:
1630 dprintk("RPC: %5u %s: server saw garbage\n",
1631 task->tk_pid, __func__);
1634 dprintk("RPC: %5u %s: server accept status: %x\n",
1635 task->tk_pid, __func__, n);
1640 task->tk_client->cl_stats->rpcgarbage++;
1641 if (task->tk_garb_retry) {
1642 task->tk_garb_retry--;
1643 dprintk("RPC: %5u %s: retrying\n",
1644 task->tk_pid, __func__);
1645 task->tk_action = call_bind;
1647 return ERR_PTR(-EAGAIN);
1652 rpc_exit(task, error);
1653 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1655 return ERR_PTR(error);
1657 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1662 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1667 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1672 static struct rpc_procinfo rpcproc_null = {
1673 .p_encode = rpcproc_encode_null,
1674 .p_decode = rpcproc_decode_null,
1677 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1679 struct rpc_message msg = {
1680 .rpc_proc = &rpcproc_null,
1683 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1684 err = rpc_call_sync(clnt, &msg, flags);
1685 put_rpccred(msg.rpc_cred);
1689 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1691 struct rpc_message msg = {
1692 .rpc_proc = &rpcproc_null,
1695 struct rpc_task_setup task_setup_data = {
1697 .rpc_message = &msg,
1698 .callback_ops = &rpc_default_ops,
1701 return rpc_run_task(&task_setup_data);
1703 EXPORT_SYMBOL_GPL(rpc_call_null);
1706 static void rpc_show_header(void)
1708 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
1709 "-timeout ---ops--\n");
1712 static void rpc_show_task(const struct rpc_clnt *clnt,
1713 const struct rpc_task *task)
1715 const char *rpc_waitq = "none";
1716 char *p, action[KSYM_SYMBOL_LEN];
1718 if (RPC_IS_QUEUED(task))
1719 rpc_waitq = rpc_qname(task->tk_waitqueue);
1721 /* map tk_action pointer to a function name; then trim off
1722 * the "+0x0 [sunrpc]" */
1723 sprint_symbol(action, (unsigned long)task->tk_action);
1724 p = strchr(action, '+');
1728 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%s q:%s\n",
1729 task->tk_pid, task->tk_flags, task->tk_status,
1730 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
1731 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task),
1735 void rpc_show_tasks(void)
1737 struct rpc_clnt *clnt;
1738 struct rpc_task *task;
1741 spin_lock(&rpc_client_lock);
1742 list_for_each_entry(clnt, &all_clients, cl_clients) {
1743 spin_lock(&clnt->cl_lock);
1744 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
1749 rpc_show_task(clnt, task);
1751 spin_unlock(&clnt->cl_lock);
1753 spin_unlock(&rpc_client_lock);