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,
295 * If the caller chooses not to specify a hostname, whip
296 * up a string representation of the passed-in address.
298 if (args->servername == NULL) {
299 servername[0] = '\0';
300 switch (args->address->sa_family) {
302 struct sockaddr_in *sin =
303 (struct sockaddr_in *)args->address;
304 snprintf(servername, sizeof(servername), "%pI4",
305 &sin->sin_addr.s_addr);
309 struct sockaddr_in6 *sin =
310 (struct sockaddr_in6 *)args->address;
311 snprintf(servername, sizeof(servername), "%pI6",
316 /* caller wants default server name, but
317 * address family isn't recognized. */
318 return ERR_PTR(-EINVAL);
320 args->servername = servername;
323 xprt = xprt_create_transport(&xprtargs);
325 return (struct rpc_clnt *)xprt;
328 * By default, kernel RPC client connects from a reserved port.
329 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
330 * but it is always enabled for rpciod, which handles the connect
334 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
337 clnt = rpc_new_client(args, xprt);
341 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
342 int err = rpc_ping(clnt, RPC_TASK_SOFT);
344 rpc_shutdown_client(clnt);
349 clnt->cl_softrtry = 1;
350 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
351 clnt->cl_softrtry = 0;
353 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
354 clnt->cl_autobind = 1;
355 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
356 clnt->cl_discrtry = 1;
357 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
362 EXPORT_SYMBOL_GPL(rpc_create);
365 * This function clones the RPC client structure. It allows us to share the
366 * same transport while varying parameters such as the authentication
370 rpc_clone_client(struct rpc_clnt *clnt)
372 struct rpc_clnt *new;
375 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
378 new->cl_parent = clnt;
379 /* Turn off autobind on clones */
380 new->cl_autobind = 0;
381 INIT_LIST_HEAD(&new->cl_tasks);
382 spin_lock_init(&new->cl_lock);
383 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
384 new->cl_metrics = rpc_alloc_iostats(clnt);
385 if (new->cl_metrics == NULL)
387 if (clnt->cl_principal) {
388 new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL);
389 if (new->cl_principal == NULL)
390 goto out_no_principal;
392 kref_init(&new->cl_kref);
393 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
397 atomic_inc(&new->cl_auth->au_count);
398 xprt_get(clnt->cl_xprt);
399 kref_get(&clnt->cl_kref);
400 rpc_register_client(new);
404 kfree(new->cl_principal);
406 rpc_free_iostats(new->cl_metrics);
410 dprintk("RPC: %s: returned error %d\n", __func__, err);
413 EXPORT_SYMBOL_GPL(rpc_clone_client);
416 * Properly shut down an RPC client, terminating all outstanding
419 void rpc_shutdown_client(struct rpc_clnt *clnt)
421 dprintk("RPC: shutting down %s client for %s\n",
422 clnt->cl_protname, clnt->cl_server);
424 while (!list_empty(&clnt->cl_tasks)) {
425 rpc_killall_tasks(clnt);
426 wait_event_timeout(destroy_wait,
427 list_empty(&clnt->cl_tasks), 1*HZ);
430 rpc_release_client(clnt);
432 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
438 rpc_free_client(struct kref *kref)
440 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
442 dprintk("RPC: destroying %s client for %s\n",
443 clnt->cl_protname, clnt->cl_server);
444 if (!IS_ERR(clnt->cl_path.dentry)) {
445 rpc_remove_client_dir(clnt->cl_path.dentry);
448 if (clnt->cl_parent != clnt) {
449 rpc_release_client(clnt->cl_parent);
452 if (clnt->cl_server != clnt->cl_inline_name)
453 kfree(clnt->cl_server);
455 rpc_unregister_client(clnt);
456 rpc_free_iostats(clnt->cl_metrics);
457 kfree(clnt->cl_principal);
458 clnt->cl_metrics = NULL;
459 xprt_put(clnt->cl_xprt);
468 rpc_free_auth(struct kref *kref)
470 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
472 if (clnt->cl_auth == NULL) {
473 rpc_free_client(kref);
478 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
479 * release remaining GSS contexts. This mechanism ensures
480 * that it can do so safely.
483 rpcauth_release(clnt->cl_auth);
484 clnt->cl_auth = NULL;
485 kref_put(kref, rpc_free_client);
489 * Release reference to the RPC client
492 rpc_release_client(struct rpc_clnt *clnt)
494 dprintk("RPC: rpc_release_client(%p)\n", clnt);
496 if (list_empty(&clnt->cl_tasks))
497 wake_up(&destroy_wait);
498 kref_put(&clnt->cl_kref, rpc_free_auth);
502 * rpc_bind_new_program - bind a new RPC program to an existing client
503 * @old: old rpc_client
504 * @program: rpc program to set
505 * @vers: rpc program version
507 * Clones the rpc client and sets up a new RPC program. This is mainly
508 * of use for enabling different RPC programs to share the same transport.
509 * The Sun NFSv2/v3 ACL protocol can do this.
511 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
512 struct rpc_program *program,
515 struct rpc_clnt *clnt;
516 struct rpc_version *version;
519 BUG_ON(vers >= program->nrvers || !program->version[vers]);
520 version = program->version[vers];
521 clnt = rpc_clone_client(old);
524 clnt->cl_procinfo = version->procs;
525 clnt->cl_maxproc = version->nrprocs;
526 clnt->cl_protname = program->name;
527 clnt->cl_prog = program->number;
528 clnt->cl_vers = version->number;
529 clnt->cl_stats = program->stats;
530 err = rpc_ping(clnt, RPC_TASK_SOFT);
532 rpc_shutdown_client(clnt);
538 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
541 * Default callback for async RPC calls
544 rpc_default_callback(struct rpc_task *task, void *data)
548 static const struct rpc_call_ops rpc_default_ops = {
549 .rpc_call_done = rpc_default_callback,
553 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
554 * @task_setup_data: pointer to task initialisation data
556 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
558 struct rpc_task *task, *ret;
560 task = rpc_new_task(task_setup_data);
562 rpc_release_calldata(task_setup_data->callback_ops,
563 task_setup_data->callback_data);
564 ret = ERR_PTR(-ENOMEM);
568 if (task->tk_status != 0) {
569 ret = ERR_PTR(task->tk_status);
573 atomic_inc(&task->tk_count);
579 EXPORT_SYMBOL_GPL(rpc_run_task);
582 * rpc_call_sync - Perform a synchronous RPC call
583 * @clnt: pointer to RPC client
584 * @msg: RPC call parameters
585 * @flags: RPC call flags
587 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
589 struct rpc_task *task;
590 struct rpc_task_setup task_setup_data = {
593 .callback_ops = &rpc_default_ops,
598 BUG_ON(flags & RPC_TASK_ASYNC);
600 task = rpc_run_task(&task_setup_data);
602 return PTR_ERR(task);
603 status = task->tk_status;
607 EXPORT_SYMBOL_GPL(rpc_call_sync);
610 * rpc_call_async - Perform an asynchronous RPC call
611 * @clnt: pointer to RPC client
612 * @msg: RPC call parameters
613 * @flags: RPC call flags
614 * @tk_ops: RPC call ops
615 * @data: user call data
618 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
619 const struct rpc_call_ops *tk_ops, void *data)
621 struct rpc_task *task;
622 struct rpc_task_setup task_setup_data = {
625 .callback_ops = tk_ops,
626 .callback_data = data,
627 .flags = flags|RPC_TASK_ASYNC,
630 task = rpc_run_task(&task_setup_data);
632 return PTR_ERR(task);
636 EXPORT_SYMBOL_GPL(rpc_call_async);
638 #if defined(CONFIG_NFS_V4_1)
640 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
641 * rpc_execute against it
644 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
645 const struct rpc_call_ops *tk_ops)
647 struct rpc_task *task;
648 struct xdr_buf *xbufp = &req->rq_snd_buf;
649 struct rpc_task_setup task_setup_data = {
650 .callback_ops = tk_ops,
653 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
655 * Create an rpc_task to send the data
657 task = rpc_new_task(&task_setup_data);
659 xprt_free_bc_request(req);
662 task->tk_rqstp = req;
665 * Set up the xdr_buf length.
666 * This also indicates that the buffer is XDR encoded already.
668 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
669 xbufp->tail[0].iov_len;
671 task->tk_action = call_bc_transmit;
672 atomic_inc(&task->tk_count);
673 BUG_ON(atomic_read(&task->tk_count) != 2);
677 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
680 #endif /* CONFIG_NFS_V4_1 */
683 rpc_call_start(struct rpc_task *task)
685 task->tk_action = call_start;
687 EXPORT_SYMBOL_GPL(rpc_call_start);
690 * rpc_peeraddr - extract remote peer address from clnt's xprt
691 * @clnt: RPC client structure
692 * @buf: target buffer
693 * @bufsize: length of target buffer
695 * Returns the number of bytes that are actually in the stored address.
697 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
700 struct rpc_xprt *xprt = clnt->cl_xprt;
702 bytes = sizeof(xprt->addr);
705 memcpy(buf, &clnt->cl_xprt->addr, bytes);
706 return xprt->addrlen;
708 EXPORT_SYMBOL_GPL(rpc_peeraddr);
711 * rpc_peeraddr2str - return remote peer address in printable format
712 * @clnt: RPC client structure
713 * @format: address format
716 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
717 enum rpc_display_format_t format)
719 struct rpc_xprt *xprt = clnt->cl_xprt;
721 if (xprt->address_strings[format] != NULL)
722 return xprt->address_strings[format];
724 return "unprintable";
726 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
729 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
731 struct rpc_xprt *xprt = clnt->cl_xprt;
732 if (xprt->ops->set_buffer_size)
733 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
735 EXPORT_SYMBOL_GPL(rpc_setbufsize);
738 * Return size of largest payload RPC client can support, in bytes
740 * For stream transports, this is one RPC record fragment (see RFC
741 * 1831), as we don't support multi-record requests yet. For datagram
742 * transports, this is the size of an IP packet minus the IP, UDP, and
745 size_t rpc_max_payload(struct rpc_clnt *clnt)
747 return clnt->cl_xprt->max_payload;
749 EXPORT_SYMBOL_GPL(rpc_max_payload);
752 * rpc_force_rebind - force transport to check that remote port is unchanged
753 * @clnt: client to rebind
756 void rpc_force_rebind(struct rpc_clnt *clnt)
758 if (clnt->cl_autobind)
759 xprt_clear_bound(clnt->cl_xprt);
761 EXPORT_SYMBOL_GPL(rpc_force_rebind);
764 * Restart an (async) RPC call from the call_prepare state.
765 * Usually called from within the exit handler.
768 rpc_restart_call_prepare(struct rpc_task *task)
770 if (RPC_ASSASSINATED(task))
772 task->tk_action = rpc_prepare_task;
774 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
777 * Restart an (async) RPC call. Usually called from within the
781 rpc_restart_call(struct rpc_task *task)
783 if (RPC_ASSASSINATED(task))
786 task->tk_action = call_start;
788 EXPORT_SYMBOL_GPL(rpc_restart_call);
791 static const char *rpc_proc_name(const struct rpc_task *task)
793 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
808 * Other FSM states can be visited zero or more times, but
809 * this state is visited exactly once for each RPC.
812 call_start(struct rpc_task *task)
814 struct rpc_clnt *clnt = task->tk_client;
816 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
817 clnt->cl_protname, clnt->cl_vers,
819 (RPC_IS_ASYNC(task) ? "async" : "sync"));
821 /* Increment call count */
822 task->tk_msg.rpc_proc->p_count++;
823 clnt->cl_stats->rpccnt++;
824 task->tk_action = call_reserve;
828 * 1. Reserve an RPC call slot
831 call_reserve(struct rpc_task *task)
835 if (!rpcauth_uptodatecred(task)) {
836 task->tk_action = call_refresh;
841 task->tk_action = call_reserveresult;
846 * 1b. Grok the result of xprt_reserve()
849 call_reserveresult(struct rpc_task *task)
851 int status = task->tk_status;
856 * After a call to xprt_reserve(), we must have either
857 * a request slot or else an error status.
861 if (task->tk_rqstp) {
862 task->tk_action = call_allocate;
866 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
868 rpc_exit(task, -EIO);
873 * Even though there was an error, we may have acquired
874 * a request slot somehow. Make sure not to leak it.
876 if (task->tk_rqstp) {
877 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
883 case -EAGAIN: /* woken up; retry */
884 task->tk_action = call_reserve;
886 case -EIO: /* probably a shutdown */
889 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
893 rpc_exit(task, status);
897 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
898 * (Note: buffer memory is freed in xprt_release).
901 call_allocate(struct rpc_task *task)
903 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
904 struct rpc_rqst *req = task->tk_rqstp;
905 struct rpc_xprt *xprt = task->tk_xprt;
906 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
911 task->tk_action = call_bind;
916 if (proc->p_proc != 0) {
917 BUG_ON(proc->p_arglen == 0);
918 if (proc->p_decode != NULL)
919 BUG_ON(proc->p_replen == 0);
923 * Calculate the size (in quads) of the RPC call
924 * and reply headers, and convert both values
927 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
928 req->rq_callsize <<= 2;
929 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
930 req->rq_rcvsize <<= 2;
932 req->rq_buffer = xprt->ops->buf_alloc(task,
933 req->rq_callsize + req->rq_rcvsize);
934 if (req->rq_buffer != NULL)
937 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
939 if (RPC_IS_ASYNC(task) || !signalled()) {
940 task->tk_action = call_allocate;
941 rpc_delay(task, HZ>>4);
945 rpc_exit(task, -ERESTARTSYS);
949 rpc_task_need_encode(struct rpc_task *task)
951 return task->tk_rqstp->rq_snd_buf.len == 0;
955 rpc_task_force_reencode(struct rpc_task *task)
957 task->tk_rqstp->rq_snd_buf.len = 0;
961 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
963 buf->head[0].iov_base = start;
964 buf->head[0].iov_len = len;
965 buf->tail[0].iov_len = 0;
973 * 3. Encode arguments of an RPC call
976 rpc_xdr_encode(struct rpc_task *task)
978 struct rpc_rqst *req = task->tk_rqstp;
984 rpc_xdr_buf_init(&req->rq_snd_buf,
987 rpc_xdr_buf_init(&req->rq_rcv_buf,
988 (char *)req->rq_buffer + req->rq_callsize,
991 p = rpc_encode_header(task);
993 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
994 rpc_exit(task, -EIO);
998 encode = task->tk_msg.rpc_proc->p_encode;
1002 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1003 task->tk_msg.rpc_argp);
1007 * 4. Get the server port number if not yet set
1010 call_bind(struct rpc_task *task)
1012 struct rpc_xprt *xprt = task->tk_xprt;
1014 dprint_status(task);
1016 task->tk_action = call_connect;
1017 if (!xprt_bound(xprt)) {
1018 task->tk_action = call_bind_status;
1019 task->tk_timeout = xprt->bind_timeout;
1020 xprt->ops->rpcbind(task);
1025 * 4a. Sort out bind result
1028 call_bind_status(struct rpc_task *task)
1032 if (task->tk_status >= 0) {
1033 dprint_status(task);
1034 task->tk_status = 0;
1035 task->tk_action = call_connect;
1039 switch (task->tk_status) {
1041 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1042 rpc_delay(task, HZ >> 2);
1045 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1046 "unavailable\n", task->tk_pid);
1047 /* fail immediately if this is an RPC ping */
1048 if (task->tk_msg.rpc_proc->p_proc == 0) {
1049 status = -EOPNOTSUPP;
1052 rpc_delay(task, 3*HZ);
1055 dprintk("RPC: %5u rpcbind request timed out\n",
1059 /* server doesn't support any rpcbind version we know of */
1060 dprintk("RPC: %5u remote rpcbind service unavailable\n",
1063 case -EPROTONOSUPPORT:
1064 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1066 task->tk_status = 0;
1067 task->tk_action = call_bind;
1070 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1071 task->tk_pid, -task->tk_status);
1074 rpc_exit(task, status);
1078 task->tk_action = call_timeout;
1082 * 4b. Connect to the RPC server
1085 call_connect(struct rpc_task *task)
1087 struct rpc_xprt *xprt = task->tk_xprt;
1089 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1091 (xprt_connected(xprt) ? "is" : "is not"));
1093 task->tk_action = call_transmit;
1094 if (!xprt_connected(xprt)) {
1095 task->tk_action = call_connect_status;
1096 if (task->tk_status < 0)
1103 * 4c. Sort out connect result
1106 call_connect_status(struct rpc_task *task)
1108 struct rpc_clnt *clnt = task->tk_client;
1109 int status = task->tk_status;
1111 dprint_status(task);
1113 task->tk_status = 0;
1114 if (status >= 0 || status == -EAGAIN) {
1115 clnt->cl_stats->netreconn++;
1116 task->tk_action = call_transmit;
1121 /* if soft mounted, test if we've timed out */
1123 task->tk_action = call_timeout;
1126 rpc_exit(task, -EIO);
1131 * 5. Transmit the RPC request, and wait for reply
1134 call_transmit(struct rpc_task *task)
1136 dprint_status(task);
1138 task->tk_action = call_status;
1139 if (task->tk_status < 0)
1141 task->tk_status = xprt_prepare_transmit(task);
1142 if (task->tk_status != 0)
1144 task->tk_action = call_transmit_status;
1145 /* Encode here so that rpcsec_gss can use correct sequence number. */
1146 if (rpc_task_need_encode(task)) {
1147 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1148 rpc_xdr_encode(task);
1149 /* Did the encode result in an error condition? */
1150 if (task->tk_status != 0) {
1151 /* Was the error nonfatal? */
1152 if (task->tk_status == -EAGAIN)
1153 rpc_delay(task, HZ >> 4);
1155 rpc_exit(task, task->tk_status);
1159 xprt_transmit(task);
1160 if (task->tk_status < 0)
1163 * On success, ensure that we call xprt_end_transmit() before sleeping
1164 * in order to allow access to the socket to other RPC requests.
1166 call_transmit_status(task);
1167 if (rpc_reply_expected(task))
1169 task->tk_action = rpc_exit_task;
1170 rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
1174 * 5a. Handle cleanup after a transmission
1177 call_transmit_status(struct rpc_task *task)
1179 task->tk_action = call_status;
1180 switch (task->tk_status) {
1184 xprt_end_transmit(task);
1186 * Special cases: if we've been waiting on the
1187 * socket's write_space() callback, or if the
1188 * socket just returned a connection error,
1189 * then hold onto the transport lock.
1198 rpc_task_force_reencode(task);
1202 #if defined(CONFIG_NFS_V4_1)
1204 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1205 * addition, disconnect on connectivity errors.
1208 call_bc_transmit(struct rpc_task *task)
1210 struct rpc_rqst *req = task->tk_rqstp;
1212 BUG_ON(task->tk_status != 0);
1213 task->tk_status = xprt_prepare_transmit(task);
1214 if (task->tk_status == -EAGAIN) {
1216 * Could not reserve the transport. Try again after the
1217 * transport is released.
1219 task->tk_status = 0;
1220 task->tk_action = call_bc_transmit;
1224 task->tk_action = rpc_exit_task;
1225 if (task->tk_status < 0) {
1226 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1227 "error: %d\n", task->tk_status);
1231 xprt_transmit(task);
1232 xprt_end_transmit(task);
1233 dprint_status(task);
1234 switch (task->tk_status) {
1243 * Problem reaching the server. Disconnect and let the
1244 * forechannel reestablish the connection. The server will
1245 * have to retransmit the backchannel request and we'll
1246 * reprocess it. Since these ops are idempotent, there's no
1247 * need to cache our reply at this time.
1249 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1250 "error: %d\n", task->tk_status);
1251 xprt_conditional_disconnect(task->tk_xprt,
1252 req->rq_connect_cookie);
1256 * We were unable to reply and will have to drop the
1257 * request. The server should reconnect and retransmit.
1259 BUG_ON(task->tk_status == -EAGAIN);
1260 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1261 "error: %d\n", task->tk_status);
1264 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1266 #endif /* CONFIG_NFS_V4_1 */
1269 * 6. Sort out the RPC call status
1272 call_status(struct rpc_task *task)
1274 struct rpc_clnt *clnt = task->tk_client;
1275 struct rpc_rqst *req = task->tk_rqstp;
1278 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1279 task->tk_status = req->rq_reply_bytes_recvd;
1281 dprint_status(task);
1283 status = task->tk_status;
1285 task->tk_action = call_decode;
1289 task->tk_status = 0;
1295 * Delay any retries for 3 seconds, then handle as if it
1298 rpc_delay(task, 3*HZ);
1300 task->tk_action = call_timeout;
1301 if (task->tk_client->cl_discrtry)
1302 xprt_conditional_disconnect(task->tk_xprt,
1303 req->rq_connect_cookie);
1307 rpc_force_rebind(clnt);
1308 rpc_delay(task, 3*HZ);
1311 task->tk_action = call_bind;
1314 task->tk_action = call_transmit;
1317 /* shutdown or soft timeout */
1318 rpc_exit(task, status);
1321 if (clnt->cl_chatty)
1322 printk("%s: RPC call returned error %d\n",
1323 clnt->cl_protname, -status);
1324 rpc_exit(task, status);
1329 * 6a. Handle RPC timeout
1330 * We do not release the request slot, so we keep using the
1331 * same XID for all retransmits.
1334 call_timeout(struct rpc_task *task)
1336 struct rpc_clnt *clnt = task->tk_client;
1338 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1339 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1343 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1344 task->tk_timeouts++;
1346 if (RPC_IS_SOFT(task)) {
1347 if (clnt->cl_chatty)
1348 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1349 clnt->cl_protname, clnt->cl_server);
1350 rpc_exit(task, -EIO);
1354 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1355 task->tk_flags |= RPC_CALL_MAJORSEEN;
1356 if (clnt->cl_chatty)
1357 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1358 clnt->cl_protname, clnt->cl_server);
1360 rpc_force_rebind(clnt);
1362 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1363 * event? RFC2203 requires the server to drop all such requests.
1365 rpcauth_invalcred(task);
1368 clnt->cl_stats->rpcretrans++;
1369 task->tk_action = call_bind;
1370 task->tk_status = 0;
1374 * 7. Decode the RPC reply
1377 call_decode(struct rpc_task *task)
1379 struct rpc_clnt *clnt = task->tk_client;
1380 struct rpc_rqst *req = task->tk_rqstp;
1381 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1384 dprintk("RPC: %5u call_decode (status %d)\n",
1385 task->tk_pid, task->tk_status);
1387 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1388 if (clnt->cl_chatty)
1389 printk(KERN_NOTICE "%s: server %s OK\n",
1390 clnt->cl_protname, clnt->cl_server);
1391 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1395 * Ensure that we see all writes made by xprt_complete_rqst()
1396 * before it changed req->rq_reply_bytes_recvd.
1399 req->rq_rcv_buf.len = req->rq_private_buf.len;
1401 /* Check that the softirq receive buffer is valid */
1402 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1403 sizeof(req->rq_rcv_buf)) != 0);
1405 if (req->rq_rcv_buf.len < 12) {
1406 if (!RPC_IS_SOFT(task)) {
1407 task->tk_action = call_bind;
1408 clnt->cl_stats->rpcretrans++;
1411 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1412 clnt->cl_protname, task->tk_status);
1413 task->tk_action = call_timeout;
1417 p = rpc_verify_header(task);
1419 if (p == ERR_PTR(-EAGAIN))
1424 task->tk_action = rpc_exit_task;
1427 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1428 task->tk_msg.rpc_resp);
1430 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1434 task->tk_status = 0;
1435 /* Note: rpc_verify_header() may have freed the RPC slot */
1436 if (task->tk_rqstp == req) {
1437 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
1438 if (task->tk_client->cl_discrtry)
1439 xprt_conditional_disconnect(task->tk_xprt,
1440 req->rq_connect_cookie);
1445 * 8. Refresh the credentials if rejected by the server
1448 call_refresh(struct rpc_task *task)
1450 dprint_status(task);
1452 task->tk_action = call_refreshresult;
1453 task->tk_status = 0;
1454 task->tk_client->cl_stats->rpcauthrefresh++;
1455 rpcauth_refreshcred(task);
1459 * 8a. Process the results of a credential refresh
1462 call_refreshresult(struct rpc_task *task)
1464 int status = task->tk_status;
1466 dprint_status(task);
1468 task->tk_status = 0;
1469 task->tk_action = call_reserve;
1470 if (status >= 0 && rpcauth_uptodatecred(task))
1472 if (status == -EACCES) {
1473 rpc_exit(task, -EACCES);
1476 task->tk_action = call_refresh;
1477 if (status != -ETIMEDOUT)
1478 rpc_delay(task, 3*HZ);
1483 rpc_encode_header(struct rpc_task *task)
1485 struct rpc_clnt *clnt = task->tk_client;
1486 struct rpc_rqst *req = task->tk_rqstp;
1487 __be32 *p = req->rq_svec[0].iov_base;
1489 /* FIXME: check buffer size? */
1491 p = xprt_skip_transport_header(task->tk_xprt, p);
1492 *p++ = req->rq_xid; /* XID */
1493 *p++ = htonl(RPC_CALL); /* CALL */
1494 *p++ = htonl(RPC_VERSION); /* RPC version */
1495 *p++ = htonl(clnt->cl_prog); /* program number */
1496 *p++ = htonl(clnt->cl_vers); /* program version */
1497 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1498 p = rpcauth_marshcred(task, p);
1499 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1504 rpc_verify_header(struct rpc_task *task)
1506 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1507 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1508 __be32 *p = iov->iov_base;
1510 int error = -EACCES;
1512 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1513 /* RFC-1014 says that the representation of XDR data must be a
1514 * multiple of four bytes
1515 * - if it isn't pointer subtraction in the NFS client may give
1518 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1519 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
1520 task->tk_rqstp->rq_rcv_buf.len);
1526 p += 1; /* skip XID */
1527 if ((n = ntohl(*p++)) != RPC_REPLY) {
1528 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1529 task->tk_pid, __func__, n);
1533 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1536 switch ((n = ntohl(*p++))) {
1537 case RPC_AUTH_ERROR:
1540 dprintk("RPC: %5u %s: RPC call version "
1542 task->tk_pid, __func__);
1543 error = -EPROTONOSUPPORT;
1546 dprintk("RPC: %5u %s: RPC call rejected, "
1547 "unknown error: %x\n",
1548 task->tk_pid, __func__, n);
1553 switch ((n = ntohl(*p++))) {
1554 case RPC_AUTH_REJECTEDCRED:
1555 case RPC_AUTH_REJECTEDVERF:
1556 case RPCSEC_GSS_CREDPROBLEM:
1557 case RPCSEC_GSS_CTXPROBLEM:
1558 if (!task->tk_cred_retry)
1560 task->tk_cred_retry--;
1561 dprintk("RPC: %5u %s: retry stale creds\n",
1562 task->tk_pid, __func__);
1563 rpcauth_invalcred(task);
1564 /* Ensure we obtain a new XID! */
1566 task->tk_action = call_refresh;
1568 case RPC_AUTH_BADCRED:
1569 case RPC_AUTH_BADVERF:
1570 /* possibly garbled cred/verf? */
1571 if (!task->tk_garb_retry)
1573 task->tk_garb_retry--;
1574 dprintk("RPC: %5u %s: retry garbled creds\n",
1575 task->tk_pid, __func__);
1576 task->tk_action = call_bind;
1578 case RPC_AUTH_TOOWEAK:
1579 printk(KERN_NOTICE "RPC: server %s requires stronger "
1580 "authentication.\n", task->tk_client->cl_server);
1583 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1584 task->tk_pid, __func__, n);
1587 dprintk("RPC: %5u %s: call rejected %d\n",
1588 task->tk_pid, __func__, n);
1591 if (!(p = rpcauth_checkverf(task, p))) {
1592 dprintk("RPC: %5u %s: auth check failed\n",
1593 task->tk_pid, __func__);
1594 goto out_garbage; /* bad verifier, retry */
1596 len = p - (__be32 *)iov->iov_base - 1;
1599 switch ((n = ntohl(*p++))) {
1602 case RPC_PROG_UNAVAIL:
1603 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1604 task->tk_pid, __func__,
1605 (unsigned int)task->tk_client->cl_prog,
1606 task->tk_client->cl_server);
1607 error = -EPFNOSUPPORT;
1609 case RPC_PROG_MISMATCH:
1610 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1611 "server %s\n", task->tk_pid, __func__,
1612 (unsigned int)task->tk_client->cl_prog,
1613 (unsigned int)task->tk_client->cl_vers,
1614 task->tk_client->cl_server);
1615 error = -EPROTONOSUPPORT;
1617 case RPC_PROC_UNAVAIL:
1618 dprintk("RPC: %5u %s: proc %s unsupported by program %u, "
1619 "version %u on server %s\n",
1620 task->tk_pid, __func__,
1621 rpc_proc_name(task),
1622 task->tk_client->cl_prog,
1623 task->tk_client->cl_vers,
1624 task->tk_client->cl_server);
1625 error = -EOPNOTSUPP;
1627 case RPC_GARBAGE_ARGS:
1628 dprintk("RPC: %5u %s: server saw garbage\n",
1629 task->tk_pid, __func__);
1632 dprintk("RPC: %5u %s: server accept status: %x\n",
1633 task->tk_pid, __func__, n);
1638 task->tk_client->cl_stats->rpcgarbage++;
1639 if (task->tk_garb_retry) {
1640 task->tk_garb_retry--;
1641 dprintk("RPC: %5u %s: retrying\n",
1642 task->tk_pid, __func__);
1643 task->tk_action = call_bind;
1645 return ERR_PTR(-EAGAIN);
1650 rpc_exit(task, error);
1651 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1653 return ERR_PTR(error);
1655 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1660 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1665 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1670 static struct rpc_procinfo rpcproc_null = {
1671 .p_encode = rpcproc_encode_null,
1672 .p_decode = rpcproc_decode_null,
1675 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1677 struct rpc_message msg = {
1678 .rpc_proc = &rpcproc_null,
1681 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1682 err = rpc_call_sync(clnt, &msg, flags);
1683 put_rpccred(msg.rpc_cred);
1687 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1689 struct rpc_message msg = {
1690 .rpc_proc = &rpcproc_null,
1693 struct rpc_task_setup task_setup_data = {
1695 .rpc_message = &msg,
1696 .callback_ops = &rpc_default_ops,
1699 return rpc_run_task(&task_setup_data);
1701 EXPORT_SYMBOL_GPL(rpc_call_null);
1704 static void rpc_show_header(void)
1706 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
1707 "-timeout ---ops--\n");
1710 static void rpc_show_task(const struct rpc_clnt *clnt,
1711 const struct rpc_task *task)
1713 const char *rpc_waitq = "none";
1714 char *p, action[KSYM_SYMBOL_LEN];
1716 if (RPC_IS_QUEUED(task))
1717 rpc_waitq = rpc_qname(task->tk_waitqueue);
1719 /* map tk_action pointer to a function name; then trim off
1720 * the "+0x0 [sunrpc]" */
1721 sprint_symbol(action, (unsigned long)task->tk_action);
1722 p = strchr(action, '+');
1726 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%s q:%s\n",
1727 task->tk_pid, task->tk_flags, task->tk_status,
1728 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
1729 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task),
1733 void rpc_show_tasks(void)
1735 struct rpc_clnt *clnt;
1736 struct rpc_task *task;
1739 spin_lock(&rpc_client_lock);
1740 list_for_each_entry(clnt, &all_clients, cl_clients) {
1741 spin_lock(&clnt->cl_lock);
1742 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
1747 rpc_show_task(clnt, task);
1749 spin_unlock(&clnt->cl_lock);
1751 spin_unlock(&rpc_client_lock);