/* * linux/net/sunrpc/clnt.c * * This file contains the high-level RPC interface. * It is modeled as a finite state machine to support both synchronous * and asynchronous requests. * * - RPC header generation and argument serialization. * - Credential refresh. * - TCP connect handling. * - Retry of operation when it is suspected the operation failed because * of uid squashing on the server, or when the credentials were stale * and need to be refreshed, or when a packet was damaged in transit. * This may be have to be moved to the VFS layer. * * NB: BSD uses a more intelligent approach to guessing when a request * or reply has been lost by keeping the RTO estimate for each procedure. * We currently make do with a constant timeout value. * * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> */ #include <asm/system.h> #include <linux/module.h> #include <linux/types.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/smp_lock.h> #include <linux/utsname.h> #include <linux/workqueue.h> #include <linux/sunrpc/clnt.h> #include <linux/sunrpc/rpc_pipe_fs.h> #include <linux/sunrpc/metrics.h> #ifdef RPC_DEBUG # define RPCDBG_FACILITY RPCDBG_CALL #endif #define dprint_status(t) \ dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ __FUNCTION__, t->tk_status) /* * All RPC clients are linked into this list */ static LIST_HEAD(all_clients); static DEFINE_SPINLOCK(rpc_client_lock); static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); static void call_start(struct rpc_task *task); static void call_reserve(struct rpc_task *task); static void call_reserveresult(struct rpc_task *task); static void call_allocate(struct rpc_task *task); static void call_encode(struct rpc_task *task); static void call_decode(struct rpc_task *task); static void call_bind(struct rpc_task *task); static void call_bind_status(struct rpc_task *task); static void call_transmit(struct rpc_task *task); static void call_status(struct rpc_task *task); static void call_transmit_status(struct rpc_task *task); static void call_refresh(struct rpc_task *task); static void call_refreshresult(struct rpc_task *task); static void call_timeout(struct rpc_task *task); static void call_connect(struct rpc_task *task); static void call_connect_status(struct rpc_task *task); static __be32 * call_header(struct rpc_task *task); static __be32 * call_verify(struct rpc_task *task); static int rpc_ping(struct rpc_clnt *clnt, int flags); static void rpc_register_client(struct rpc_clnt *clnt) { spin_lock(&rpc_client_lock); list_add(&clnt->cl_clients, &all_clients); spin_unlock(&rpc_client_lock); } static void rpc_unregister_client(struct rpc_clnt *clnt) { spin_lock(&rpc_client_lock); list_del(&clnt->cl_clients); spin_unlock(&rpc_client_lock); } static int rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name) { static uint32_t clntid; int error; clnt->cl_vfsmnt = ERR_PTR(-ENOENT); clnt->cl_dentry = ERR_PTR(-ENOENT); if (dir_name == NULL) return 0; clnt->cl_vfsmnt = rpc_get_mount(); if (IS_ERR(clnt->cl_vfsmnt)) return PTR_ERR(clnt->cl_vfsmnt); for (;;) { snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname), "%s/clnt%x", dir_name, (unsigned int)clntid++); clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0'; clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt); if (!IS_ERR(clnt->cl_dentry)) return 0; error = PTR_ERR(clnt->cl_dentry); if (error != -EEXIST) { printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n", clnt->cl_pathname, error); rpc_put_mount(); return error; } } } static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor) { struct rpc_version *version; struct rpc_clnt *clnt = NULL; struct rpc_auth *auth; int err; size_t len; /* sanity check the name before trying to print it */ err = -EINVAL; len = strlen(servname); if (len > RPC_MAXNETNAMELEN) goto out_no_rpciod; len++; dprintk("RPC: creating %s client for %s (xprt %p)\n", program->name, servname, xprt); err = rpciod_up(); if (err) goto out_no_rpciod; err = -EINVAL; if (!xprt) goto out_no_xprt; if (vers >= program->nrvers || !(version = program->version[vers])) goto out_err; err = -ENOMEM; clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); if (!clnt) goto out_err; clnt->cl_parent = clnt; clnt->cl_server = clnt->cl_inline_name; if (len > sizeof(clnt->cl_inline_name)) { char *buf = kmalloc(len, GFP_KERNEL); if (buf != 0) clnt->cl_server = buf; else len = sizeof(clnt->cl_inline_name); } strlcpy(clnt->cl_server, servname, len); clnt->cl_xprt = xprt; clnt->cl_procinfo = version->procs; clnt->cl_maxproc = version->nrprocs; clnt->cl_protname = program->name; clnt->cl_prog = program->number; clnt->cl_vers = version->number; clnt->cl_stats = program->stats; clnt->cl_metrics = rpc_alloc_iostats(clnt); err = -ENOMEM; if (clnt->cl_metrics == NULL) goto out_no_stats; clnt->cl_program = program; INIT_LIST_HEAD(&clnt->cl_tasks); spin_lock_init(&clnt->cl_lock); if (!xprt_bound(clnt->cl_xprt)) clnt->cl_autobind = 1; clnt->cl_rtt = &clnt->cl_rtt_default; rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval); kref_init(&clnt->cl_kref); err = rpc_setup_pipedir(clnt, program->pipe_dir_name); if (err < 0) goto out_no_path; auth = rpcauth_create(flavor, clnt); if (IS_ERR(auth)) { printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", flavor); err = PTR_ERR(auth); goto out_no_auth; } /* save the nodename */ clnt->cl_nodelen = strlen(utsname()->nodename); if (clnt->cl_nodelen > UNX_MAXNODENAME) clnt->cl_nodelen = UNX_MAXNODENAME; memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen); rpc_register_client(clnt); return clnt; out_no_auth: if (!IS_ERR(clnt->cl_dentry)) { rpc_rmdir(clnt->cl_dentry); rpc_put_mount(); } out_no_path: rpc_free_iostats(clnt->cl_metrics); out_no_stats: if (clnt->cl_server != clnt->cl_inline_name) kfree(clnt->cl_server); kfree(clnt); out_err: xprt_put(xprt); out_no_xprt: rpciod_down(); out_no_rpciod: return ERR_PTR(err); } /* * rpc_create - create an RPC client and transport with one call * @args: rpc_clnt create argument structure * * Creates and initializes an RPC transport and an RPC client. * * It can ping the server in order to determine if it is up, and to see if * it supports this program and version. RPC_CLNT_CREATE_NOPING disables * this behavior so asynchronous tasks can also use rpc_create. */ struct rpc_clnt *rpc_create(struct rpc_create_args *args) { struct rpc_xprt *xprt; struct rpc_clnt *clnt; struct xprt_create xprtargs = { .ident = args->protocol, .srcaddr = args->saddress, .dstaddr = args->address, .addrlen = args->addrsize, .timeout = args->timeout }; char servername[20]; xprt = xprt_create_transport(&xprtargs); if (IS_ERR(xprt)) return (struct rpc_clnt *)xprt; /* * If the caller chooses not to specify a hostname, whip * up a string representation of the passed-in address. */ if (args->servername == NULL) { struct sockaddr_in *addr = (struct sockaddr_in *) args->address; snprintf(servername, sizeof(servername), NIPQUAD_FMT, NIPQUAD(addr->sin_addr.s_addr)); args->servername = servername; } /* * By default, kernel RPC client connects from a reserved port. * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, * but it is always enabled for rpciod, which handles the connect * operation. */ xprt->resvport = 1; if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) xprt->resvport = 0; clnt = rpc_new_client(xprt, args->servername, args->program, args->version, args->authflavor); if (IS_ERR(clnt)) return clnt; if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); if (err != 0) { rpc_shutdown_client(clnt); return ERR_PTR(err); } } clnt->cl_softrtry = 1; if (args->flags & RPC_CLNT_CREATE_HARDRTRY) clnt->cl_softrtry = 0; if (args->flags & RPC_CLNT_CREATE_INTR) clnt->cl_intr = 1; if (args->flags & RPC_CLNT_CREATE_AUTOBIND) clnt->cl_autobind = 1; if (args->flags & RPC_CLNT_CREATE_DISCRTRY) clnt->cl_discrtry = 1; return clnt; } EXPORT_SYMBOL_GPL(rpc_create); /* * This function clones the RPC client structure. It allows us to share the * same transport while varying parameters such as the authentication * flavour. */ struct rpc_clnt * rpc_clone_client(struct rpc_clnt *clnt) { struct rpc_clnt *new; int err = -ENOMEM; new = kmemdup(clnt, sizeof(*new), GFP_KERNEL); if (!new) goto out_no_clnt; new->cl_parent = clnt; /* Turn off autobind on clones */ new->cl_autobind = 0; INIT_LIST_HEAD(&new->cl_tasks); spin_lock_init(&new->cl_lock); rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval); new->cl_metrics = rpc_alloc_iostats(clnt); if (new->cl_metrics == NULL) goto out_no_stats; kref_init(&new->cl_kref); err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name); if (err != 0) goto out_no_path; if (new->cl_auth) atomic_inc(&new->cl_auth->au_count); xprt_get(clnt->cl_xprt); kref_get(&clnt->cl_kref); rpc_register_client(new); rpciod_up(); return new; out_no_path: rpc_free_iostats(new->cl_metrics); out_no_stats: kfree(new); out_no_clnt: dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err); return ERR_PTR(err); } EXPORT_SYMBOL_GPL(rpc_clone_client); /* * Properly shut down an RPC client, terminating all outstanding * requests. */ void rpc_shutdown_client(struct rpc_clnt *clnt) { dprintk("RPC: shutting down %s client for %s\n", clnt->cl_protname, clnt->cl_server); while (!list_empty(&clnt->cl_tasks)) { rpc_killall_tasks(clnt); wait_event_timeout(destroy_wait, list_empty(&clnt->cl_tasks), 1*HZ); } rpc_release_client(clnt); } EXPORT_SYMBOL_GPL(rpc_shutdown_client); /* * Free an RPC client */ static void rpc_free_client(struct kref *kref) { struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref); dprintk("RPC: destroying %s client for %s\n", clnt->cl_protname, clnt->cl_server); if (!IS_ERR(clnt->cl_dentry)) { rpc_rmdir(clnt->cl_dentry); rpc_put_mount(); } if (clnt->cl_parent != clnt) { rpc_release_client(clnt->cl_parent); goto out_free; } if (clnt->cl_server != clnt->cl_inline_name) kfree(clnt->cl_server); out_free: rpc_unregister_client(clnt); rpc_free_iostats(clnt->cl_metrics); clnt->cl_metrics = NULL; xprt_put(clnt->cl_xprt); rpciod_down(); kfree(clnt); } /* * Free an RPC client */ static void rpc_free_auth(struct kref *kref) { struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref); if (clnt->cl_auth == NULL) { rpc_free_client(kref); return; } /* * Note: RPCSEC_GSS may need to send NULL RPC calls in order to * release remaining GSS contexts. This mechanism ensures * that it can do so safely. */ kref_init(kref); rpcauth_release(clnt->cl_auth); clnt->cl_auth = NULL; kref_put(kref, rpc_free_client); } /* * Release reference to the RPC client */ void rpc_release_client(struct rpc_clnt *clnt) { dprintk("RPC: rpc_release_client(%p)\n", clnt); if (list_empty(&clnt->cl_tasks)) wake_up(&destroy_wait); kref_put(&clnt->cl_kref, rpc_free_auth); } /** * rpc_bind_new_program - bind a new RPC program to an existing client * @old - old rpc_client * @program - rpc program to set * @vers - rpc program version * * Clones the rpc client and sets up a new RPC program. This is mainly * of use for enabling different RPC programs to share the same transport. * The Sun NFSv2/v3 ACL protocol can do this. */ struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, struct rpc_program *program, u32 vers) { struct rpc_clnt *clnt; struct rpc_version *version; int err; BUG_ON(vers >= program->nrvers || !program->version[vers]); version = program->version[vers]; clnt = rpc_clone_client(old); if (IS_ERR(clnt)) goto out; clnt->cl_procinfo = version->procs; clnt->cl_maxproc = version->nrprocs; clnt->cl_protname = program->name; clnt->cl_prog = program->number; clnt->cl_vers = version->number; clnt->cl_stats = program->stats; err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); if (err != 0) { rpc_shutdown_client(clnt); clnt = ERR_PTR(err); } out: return clnt; } EXPORT_SYMBOL_GPL(rpc_bind_new_program); /* * Default callback for async RPC calls */ static void rpc_default_callback(struct rpc_task *task, void *data) { } static const struct rpc_call_ops rpc_default_ops = { .rpc_call_done = rpc_default_callback, }; /* * Export the signal mask handling for synchronous code that * sleeps on RPC calls */ #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM)) static void rpc_save_sigmask(sigset_t *oldset, int intr) { unsigned long sigallow = sigmask(SIGKILL); sigset_t sigmask; /* Block all signals except those listed in sigallow */ if (intr) sigallow |= RPC_INTR_SIGNALS; siginitsetinv(&sigmask, sigallow); sigprocmask(SIG_BLOCK, &sigmask, oldset); } static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset) { rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task)); } static inline void rpc_restore_sigmask(sigset_t *oldset) { sigprocmask(SIG_SETMASK, oldset, NULL); } void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset) { rpc_save_sigmask(oldset, clnt->cl_intr); } EXPORT_SYMBOL_GPL(rpc_clnt_sigmask); void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset) { rpc_restore_sigmask(oldset); } EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask); /** * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it * @task_setup_data: pointer to task initialisation data */ struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) { struct rpc_task *task, *ret; sigset_t oldset; task = rpc_new_task(task_setup_data); if (task == NULL) { rpc_release_calldata(task_setup_data->callback_ops, task_setup_data->callback_data); return ERR_PTR(-ENOMEM); } /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */ rpc_task_sigmask(task, &oldset); if (task_setup_data->rpc_message != NULL) { rpc_call_setup(task, task_setup_data->rpc_message, 0); if (task->tk_status != 0) { ret = ERR_PTR(task->tk_status); rpc_put_task(task); goto out; } } atomic_inc(&task->tk_count); rpc_execute(task); ret = task; out: rpc_restore_sigmask(&oldset); return ret; } EXPORT_SYMBOL_GPL(rpc_run_task); /** * rpc_call_sync - Perform a synchronous RPC call * @clnt: pointer to RPC client * @msg: RPC call parameters * @flags: RPC call flags */ int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) { struct rpc_task *task; struct rpc_task_setup task_setup_data = { .rpc_client = clnt, .rpc_message = msg, .callback_ops = &rpc_default_ops, .flags = flags, }; int status; BUG_ON(flags & RPC_TASK_ASYNC); task = rpc_run_task(&task_setup_data); if (IS_ERR(task)) return PTR_ERR(task); status = task->tk_status; rpc_put_task(task); return status; } EXPORT_SYMBOL_GPL(rpc_call_sync); /** * rpc_call_async - Perform an asynchronous RPC call * @clnt: pointer to RPC client * @msg: RPC call parameters * @flags: RPC call flags * @ops: RPC call ops * @data: user call data */ int rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags, const struct rpc_call_ops *tk_ops, void *data) { struct rpc_task *task; struct rpc_task_setup task_setup_data = { .rpc_client = clnt, .rpc_message = msg, .callback_ops = tk_ops, .callback_data = data, .flags = flags|RPC_TASK_ASYNC, }; task = rpc_run_task(&task_setup_data); if (IS_ERR(task)) return PTR_ERR(task); rpc_put_task(task); return 0; } EXPORT_SYMBOL_GPL(rpc_call_async); void rpc_call_setup(struct rpc_task *task, const struct rpc_message *msg, int flags) { task->tk_msg = *msg; task->tk_flags |= flags; /* Bind the user cred */ if (task->tk_msg.rpc_cred != NULL) rpcauth_holdcred(task); else rpcauth_bindcred(task); if (task->tk_status == 0) task->tk_action = call_start; else task->tk_action = rpc_exit_task; } EXPORT_SYMBOL_GPL(rpc_call_setup); /** * rpc_peeraddr - extract remote peer address from clnt's xprt * @clnt: RPC client structure * @buf: target buffer * @size: length of target buffer * * Returns the number of bytes that are actually in the stored address. */ size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) { size_t bytes; struct rpc_xprt *xprt = clnt->cl_xprt; bytes = sizeof(xprt->addr); if (bytes > bufsize) bytes = bufsize; memcpy(buf, &clnt->cl_xprt->addr, bytes); return xprt->addrlen; } EXPORT_SYMBOL_GPL(rpc_peeraddr); /** * rpc_peeraddr2str - return remote peer address in printable format * @clnt: RPC client structure * @format: address format * */ char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format) { struct rpc_xprt *xprt = clnt->cl_xprt; if (xprt->address_strings[format] != NULL) return xprt->address_strings[format]; else return "unprintable"; } EXPORT_SYMBOL_GPL(rpc_peeraddr2str); void rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) { struct rpc_xprt *xprt = clnt->cl_xprt; if (xprt->ops->set_buffer_size) xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); } EXPORT_SYMBOL_GPL(rpc_setbufsize); /* * Return size of largest payload RPC client can support, in bytes * * For stream transports, this is one RPC record fragment (see RFC * 1831), as we don't support multi-record requests yet. For datagram * transports, this is the size of an IP packet minus the IP, UDP, and * RPC header sizes. */ size_t rpc_max_payload(struct rpc_clnt *clnt) { return clnt->cl_xprt->max_payload; } EXPORT_SYMBOL_GPL(rpc_max_payload); /** * rpc_force_rebind - force transport to check that remote port is unchanged * @clnt: client to rebind * */ void rpc_force_rebind(struct rpc_clnt *clnt) { if (clnt->cl_autobind) xprt_clear_bound(clnt->cl_xprt); } EXPORT_SYMBOL_GPL(rpc_force_rebind); /* * Restart an (async) RPC call. Usually called from within the * exit handler. */ void rpc_restart_call(struct rpc_task *task) { if (RPC_ASSASSINATED(task)) return; task->tk_action = call_start; } EXPORT_SYMBOL_GPL(rpc_restart_call); /* * 0. Initial state * * Other FSM states can be visited zero or more times, but * this state is visited exactly once for each RPC. */ static void call_start(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid, clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc, (RPC_IS_ASYNC(task) ? "async" : "sync")); /* Increment call count */ task->tk_msg.rpc_proc->p_count++; clnt->cl_stats->rpccnt++; task->tk_action = call_reserve; } /* * 1. Reserve an RPC call slot */ static void call_reserve(struct rpc_task *task) { dprint_status(task); if (!rpcauth_uptodatecred(task)) { task->tk_action = call_refresh; return; } task->tk_status = 0; task->tk_action = call_reserveresult; xprt_reserve(task); } /* * 1b. Grok the result of xprt_reserve() */ static void call_reserveresult(struct rpc_task *task) { int status = task->tk_status; dprint_status(task); /* * After a call to xprt_reserve(), we must have either * a request slot or else an error status. */ task->tk_status = 0; if (status >= 0) { if (task->tk_rqstp) { task->tk_action = call_allocate; return; } printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", __FUNCTION__, status); rpc_exit(task, -EIO); return; } /* * Even though there was an error, we may have acquired * a request slot somehow. Make sure not to leak it. */ if (task->tk_rqstp) { printk(KERN_ERR "%s: status=%d, request allocated anyway\n", __FUNCTION__, status); xprt_release(task); } switch (status) { case -EAGAIN: /* woken up; retry */ task->tk_action = call_reserve; return; case -EIO: /* probably a shutdown */ break; default: printk(KERN_ERR "%s: unrecognized error %d, exiting\n", __FUNCTION__, status); break; } rpc_exit(task, status); } /* * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. * (Note: buffer memory is freed in xprt_release). */ static void call_allocate(struct rpc_task *task) { unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack; struct rpc_rqst *req = task->tk_rqstp; struct rpc_xprt *xprt = task->tk_xprt; struct rpc_procinfo *proc = task->tk_msg.rpc_proc; dprint_status(task); task->tk_status = 0; task->tk_action = call_bind; if (req->rq_buffer) return; if (proc->p_proc != 0) { BUG_ON(proc->p_arglen == 0); if (proc->p_decode != NULL) BUG_ON(proc->p_replen == 0); } /* * Calculate the size (in quads) of the RPC call * and reply headers, and convert both values * to byte sizes. */ req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; req->rq_callsize <<= 2; req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; req->rq_rcvsize <<= 2; req->rq_buffer = xprt->ops->buf_alloc(task, req->rq_callsize + req->rq_rcvsize); if (req->rq_buffer != NULL) return; dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); if (RPC_IS_ASYNC(task) || !signalled()) { task->tk_action = call_allocate; rpc_delay(task, HZ>>4); return; } rpc_exit(task, -ERESTARTSYS); } static inline int rpc_task_need_encode(struct rpc_task *task) { return task->tk_rqstp->rq_snd_buf.len == 0; } static inline void rpc_task_force_reencode(struct rpc_task *task) { task->tk_rqstp->rq_snd_buf.len = 0; } static inline void rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) { buf->head[0].iov_base = start; buf->head[0].iov_len = len; buf->tail[0].iov_len = 0; buf->page_len = 0; buf->flags = 0; buf->len = 0; buf->buflen = len; } /* * 3. Encode arguments of an RPC call */ static void call_encode(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; kxdrproc_t encode; __be32 *p; dprint_status(task); rpc_xdr_buf_init(&req->rq_snd_buf, req->rq_buffer, req->rq_callsize); rpc_xdr_buf_init(&req->rq_rcv_buf, (char *)req->rq_buffer + req->rq_callsize, req->rq_rcvsize); /* Encode header and provided arguments */ encode = task->tk_msg.rpc_proc->p_encode; if (!(p = call_header(task))) { printk(KERN_INFO "RPC: call_header failed, exit EIO\n"); rpc_exit(task, -EIO); return; } if (encode == NULL) return; task->tk_status = rpcauth_wrap_req(task, encode, req, p, task->tk_msg.rpc_argp); if (task->tk_status == -ENOMEM) { /* XXX: Is this sane? */ rpc_delay(task, 3*HZ); task->tk_status = -EAGAIN; } } /* * 4. Get the server port number if not yet set */ static void call_bind(struct rpc_task *task) { struct rpc_xprt *xprt = task->tk_xprt; dprint_status(task); task->tk_action = call_connect; if (!xprt_bound(xprt)) { task->tk_action = call_bind_status; task->tk_timeout = xprt->bind_timeout; xprt->ops->rpcbind(task); } } /* * 4a. Sort out bind result */ static void call_bind_status(struct rpc_task *task) { int status = -EIO; if (task->tk_status >= 0) { dprint_status(task); task->tk_status = 0; task->tk_action = call_connect; return; } switch (task->tk_status) { case -EAGAIN: dprintk("RPC: %5u rpcbind waiting for another request " "to finish\n", task->tk_pid); /* avoid busy-waiting here -- could be a network outage. */ rpc_delay(task, 5*HZ); goto retry_timeout; case -EACCES: dprintk("RPC: %5u remote rpcbind: RPC program/version " "unavailable\n", task->tk_pid); /* fail immediately if this is an RPC ping */ if (task->tk_msg.rpc_proc->p_proc == 0) { status = -EOPNOTSUPP; break; } rpc_delay(task, 3*HZ); goto retry_timeout; case -ETIMEDOUT: dprintk("RPC: %5u rpcbind request timed out\n", task->tk_pid); goto retry_timeout; case -EPFNOSUPPORT: /* server doesn't support any rpcbind version we know of */ dprintk("RPC: %5u remote rpcbind service unavailable\n", task->tk_pid); break; case -EPROTONOSUPPORT: dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", task->tk_pid); task->tk_status = 0; task->tk_action = call_bind; return; default: dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", task->tk_pid, -task->tk_status); } rpc_exit(task, status); return; retry_timeout: task->tk_action = call_timeout; } /* * 4b. Connect to the RPC server */ static void call_connect(struct rpc_task *task) { struct rpc_xprt *xprt = task->tk_xprt; dprintk("RPC: %5u call_connect xprt %p %s connected\n", task->tk_pid, xprt, (xprt_connected(xprt) ? "is" : "is not")); task->tk_action = call_transmit; if (!xprt_connected(xprt)) { task->tk_action = call_connect_status; if (task->tk_status < 0) return; xprt_connect(task); } } /* * 4c. Sort out connect result */ static void call_connect_status(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; int status = task->tk_status; dprint_status(task); task->tk_status = 0; if (status >= 0) { clnt->cl_stats->netreconn++; task->tk_action = call_transmit; return; } /* Something failed: remote service port may have changed */ rpc_force_rebind(clnt); switch (status) { case -ENOTCONN: case -EAGAIN: task->tk_action = call_bind; if (!RPC_IS_SOFT(task)) return; /* if soft mounted, test if we've timed out */ case -ETIMEDOUT: task->tk_action = call_timeout; return; } rpc_exit(task, -EIO); } /* * 5. Transmit the RPC request, and wait for reply */ static void call_transmit(struct rpc_task *task) { dprint_status(task); task->tk_action = call_status; if (task->tk_status < 0) return; task->tk_status = xprt_prepare_transmit(task); if (task->tk_status != 0) return; task->tk_action = call_transmit_status; /* Encode here so that rpcsec_gss can use correct sequence number. */ if (rpc_task_need_encode(task)) { BUG_ON(task->tk_rqstp->rq_bytes_sent != 0); call_encode(task); /* Did the encode result in an error condition? */ if (task->tk_status != 0) return; } xprt_transmit(task); if (task->tk_status < 0) return; /* * On success, ensure that we call xprt_end_transmit() before sleeping * in order to allow access to the socket to other RPC requests. */ call_transmit_status(task); if (task->tk_msg.rpc_proc->p_decode != NULL) return; task->tk_action = rpc_exit_task; rpc_wake_up_task(task); } /* * 5a. Handle cleanup after a transmission */ static void call_transmit_status(struct rpc_task *task) { task->tk_action = call_status; /* * Special case: if we've been waiting on the socket's write_space() * callback, then don't call xprt_end_transmit(). */ if (task->tk_status == -EAGAIN) return; xprt_end_transmit(task); rpc_task_force_reencode(task); } /* * 6. Sort out the RPC call status */ static void call_status(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; struct rpc_rqst *req = task->tk_rqstp; int status; if (req->rq_received > 0 && !req->rq_bytes_sent) task->tk_status = req->rq_received; dprint_status(task); status = task->tk_status; if (status >= 0) { task->tk_action = call_decode; return; } task->tk_status = 0; switch(status) { case -EHOSTDOWN: case -EHOSTUNREACH: case -ENETUNREACH: /* * Delay any retries for 3 seconds, then handle as if it * were a timeout. */ rpc_delay(task, 3*HZ); case -ETIMEDOUT: task->tk_action = call_timeout; if (task->tk_client->cl_discrtry) xprt_force_disconnect(task->tk_xprt); break; case -ECONNREFUSED: case -ENOTCONN: rpc_force_rebind(clnt); task->tk_action = call_bind; break; case -EAGAIN: task->tk_action = call_transmit; break; case -EIO: /* shutdown or soft timeout */ rpc_exit(task, status); break; default: printk("%s: RPC call returned error %d\n", clnt->cl_protname, -status); rpc_exit(task, status); } } /* * 6a. Handle RPC timeout * We do not release the request slot, so we keep using the * same XID for all retransmits. */ static void call_timeout(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; if (xprt_adjust_timeout(task->tk_rqstp) == 0) { dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); goto retry; } dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); task->tk_timeouts++; if (RPC_IS_SOFT(task)) { printk(KERN_NOTICE "%s: server %s not responding, timed out\n", clnt->cl_protname, clnt->cl_server); rpc_exit(task, -EIO); return; } if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { task->tk_flags |= RPC_CALL_MAJORSEEN; printk(KERN_NOTICE "%s: server %s not responding, still trying\n", clnt->cl_protname, clnt->cl_server); } rpc_force_rebind(clnt); retry: clnt->cl_stats->rpcretrans++; task->tk_action = call_bind; task->tk_status = 0; } /* * 7. Decode the RPC reply */ static void call_decode(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; struct rpc_rqst *req = task->tk_rqstp; kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; __be32 *p; dprintk("RPC: %5u call_decode (status %d)\n", task->tk_pid, task->tk_status); if (task->tk_flags & RPC_CALL_MAJORSEEN) { printk(KERN_NOTICE "%s: server %s OK\n", clnt->cl_protname, clnt->cl_server); task->tk_flags &= ~RPC_CALL_MAJORSEEN; } if (task->tk_status < 12) { if (!RPC_IS_SOFT(task)) { task->tk_action = call_bind; clnt->cl_stats->rpcretrans++; goto out_retry; } dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", clnt->cl_protname, task->tk_status); task->tk_action = call_timeout; goto out_retry; } /* * Ensure that we see all writes made by xprt_complete_rqst() * before it changed req->rq_received. */ smp_rmb(); req->rq_rcv_buf.len = req->rq_private_buf.len; /* Check that the softirq receive buffer is valid */ WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, sizeof(req->rq_rcv_buf)) != 0); /* Verify the RPC header */ p = call_verify(task); if (IS_ERR(p)) { if (p == ERR_PTR(-EAGAIN)) goto out_retry; return; } task->tk_action = rpc_exit_task; if (decode) { task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, task->tk_msg.rpc_resp); } dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, task->tk_status); return; out_retry: req->rq_received = req->rq_private_buf.len = 0; task->tk_status = 0; if (task->tk_client->cl_discrtry) xprt_force_disconnect(task->tk_xprt); } /* * 8. Refresh the credentials if rejected by the server */ static void call_refresh(struct rpc_task *task) { dprint_status(task); task->tk_action = call_refreshresult; task->tk_status = 0; task->tk_client->cl_stats->rpcauthrefresh++; rpcauth_refreshcred(task); } /* * 8a. Process the results of a credential refresh */ static void call_refreshresult(struct rpc_task *task) { int status = task->tk_status; dprint_status(task); task->tk_status = 0; task->tk_action = call_reserve; if (status >= 0 && rpcauth_uptodatecred(task)) return; if (status == -EACCES) { rpc_exit(task, -EACCES); return; } task->tk_action = call_refresh; if (status != -ETIMEDOUT) rpc_delay(task, 3*HZ); return; } /* * Call header serialization */ static __be32 * call_header(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; struct rpc_rqst *req = task->tk_rqstp; __be32 *p = req->rq_svec[0].iov_base; /* FIXME: check buffer size? */ p = xprt_skip_transport_header(task->tk_xprt, p); *p++ = req->rq_xid; /* XID */ *p++ = htonl(RPC_CALL); /* CALL */ *p++ = htonl(RPC_VERSION); /* RPC version */ *p++ = htonl(clnt->cl_prog); /* program number */ *p++ = htonl(clnt->cl_vers); /* program version */ *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ p = rpcauth_marshcred(task, p); req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); return p; } /* * Reply header verification */ static __be32 * call_verify(struct rpc_task *task) { struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; int len = task->tk_rqstp->rq_rcv_buf.len >> 2; __be32 *p = iov->iov_base; u32 n; int error = -EACCES; if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { /* RFC-1014 says that the representation of XDR data must be a * multiple of four bytes * - if it isn't pointer subtraction in the NFS client may give * undefined results */ dprintk("RPC: %5u %s: XDR representation not a multiple of" " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__, task->tk_rqstp->rq_rcv_buf.len); goto out_eio; } if ((len -= 3) < 0) goto out_overflow; p += 1; /* skip XID */ if ((n = ntohl(*p++)) != RPC_REPLY) { dprintk("RPC: %5u %s: not an RPC reply: %x\n", task->tk_pid, __FUNCTION__, n); goto out_garbage; } if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { if (--len < 0) goto out_overflow; switch ((n = ntohl(*p++))) { case RPC_AUTH_ERROR: break; case RPC_MISMATCH: dprintk("RPC: %5u %s: RPC call version " "mismatch!\n", task->tk_pid, __FUNCTION__); error = -EPROTONOSUPPORT; goto out_err; default: dprintk("RPC: %5u %s: RPC call rejected, " "unknown error: %x\n", task->tk_pid, __FUNCTION__, n); goto out_eio; } if (--len < 0) goto out_overflow; switch ((n = ntohl(*p++))) { case RPC_AUTH_REJECTEDCRED: case RPC_AUTH_REJECTEDVERF: case RPCSEC_GSS_CREDPROBLEM: case RPCSEC_GSS_CTXPROBLEM: if (!task->tk_cred_retry) break; task->tk_cred_retry--; dprintk("RPC: %5u %s: retry stale creds\n", task->tk_pid, __FUNCTION__); rpcauth_invalcred(task); /* Ensure we obtain a new XID! */ xprt_release(task); task->tk_action = call_refresh; goto out_retry; case RPC_AUTH_BADCRED: case RPC_AUTH_BADVERF: /* possibly garbled cred/verf? */ if (!task->tk_garb_retry) break; task->tk_garb_retry--; dprintk("RPC: %5u %s: retry garbled creds\n", task->tk_pid, __FUNCTION__); task->tk_action = call_bind; goto out_retry; case RPC_AUTH_TOOWEAK: printk(KERN_NOTICE "call_verify: server %s requires stronger " "authentication.\n", task->tk_client->cl_server); break; default: dprintk("RPC: %5u %s: unknown auth error: %x\n", task->tk_pid, __FUNCTION__, n); error = -EIO; } dprintk("RPC: %5u %s: call rejected %d\n", task->tk_pid, __FUNCTION__, n); goto out_err; } if (!(p = rpcauth_checkverf(task, p))) { dprintk("RPC: %5u %s: auth check failed\n", task->tk_pid, __FUNCTION__); goto out_garbage; /* bad verifier, retry */ } len = p - (__be32 *)iov->iov_base - 1; if (len < 0) goto out_overflow; switch ((n = ntohl(*p++))) { case RPC_SUCCESS: return p; case RPC_PROG_UNAVAIL: dprintk("RPC: %5u %s: program %u is unsupported by server %s\n", task->tk_pid, __FUNCTION__, (unsigned int)task->tk_client->cl_prog, task->tk_client->cl_server); error = -EPFNOSUPPORT; goto out_err; case RPC_PROG_MISMATCH: dprintk("RPC: %5u %s: program %u, version %u unsupported by " "server %s\n", task->tk_pid, __FUNCTION__, (unsigned int)task->tk_client->cl_prog, (unsigned int)task->tk_client->cl_vers, task->tk_client->cl_server); error = -EPROTONOSUPPORT; goto out_err; case RPC_PROC_UNAVAIL: dprintk("RPC: %5u %s: proc %p unsupported by program %u, " "version %u on server %s\n", task->tk_pid, __FUNCTION__, task->tk_msg.rpc_proc, task->tk_client->cl_prog, task->tk_client->cl_vers, task->tk_client->cl_server); error = -EOPNOTSUPP; goto out_err; case RPC_GARBAGE_ARGS: dprintk("RPC: %5u %s: server saw garbage\n", task->tk_pid, __FUNCTION__); break; /* retry */ default: dprintk("RPC: %5u %s: server accept status: %x\n", task->tk_pid, __FUNCTION__, n); /* Also retry */ } out_garbage: task->tk_client->cl_stats->rpcgarbage++; if (task->tk_garb_retry) { task->tk_garb_retry--; dprintk("RPC: %5u %s: retrying\n", task->tk_pid, __FUNCTION__); task->tk_action = call_bind; out_retry: return ERR_PTR(-EAGAIN); } out_eio: error = -EIO; out_err: rpc_exit(task, error); dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, __FUNCTION__, error); return ERR_PTR(error); out_overflow: dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, __FUNCTION__); goto out_garbage; } static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj) { return 0; } static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj) { return 0; } static struct rpc_procinfo rpcproc_null = { .p_encode = rpcproc_encode_null, .p_decode = rpcproc_decode_null, }; static int rpc_ping(struct rpc_clnt *clnt, int flags) { struct rpc_message msg = { .rpc_proc = &rpcproc_null, }; int err; msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); err = rpc_call_sync(clnt, &msg, flags); put_rpccred(msg.rpc_cred); return err; } struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) { struct rpc_message msg = { .rpc_proc = &rpcproc_null, .rpc_cred = cred, }; struct rpc_task_setup task_setup_data = { .rpc_client = clnt, .rpc_message = &msg, .callback_ops = &rpc_default_ops, .flags = flags, }; return rpc_run_task(&task_setup_data); } EXPORT_SYMBOL_GPL(rpc_call_null); #ifdef RPC_DEBUG void rpc_show_tasks(void) { struct rpc_clnt *clnt; struct rpc_task *t; spin_lock(&rpc_client_lock); if (list_empty(&all_clients)) goto out; printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout " "-rpcwait -action- ---ops--\n"); list_for_each_entry(clnt, &all_clients, cl_clients) { if (list_empty(&clnt->cl_tasks)) continue; spin_lock(&clnt->cl_lock); list_for_each_entry(t, &clnt->cl_tasks, tk_task) { const char *rpc_waitq = "none"; int proc; if (t->tk_msg.rpc_proc) proc = t->tk_msg.rpc_proc->p_proc; else proc = -1; if (RPC_IS_QUEUED(t)) rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq); printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n", t->tk_pid, proc, t->tk_flags, t->tk_status, t->tk_client, (t->tk_client ? t->tk_client->cl_prog : 0), t->tk_rqstp, t->tk_timeout, rpc_waitq, t->tk_action, t->tk_ops); } spin_unlock(&clnt->cl_lock); } out: spin_unlock(&rpc_client_lock); } #endif