/* * 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. * * Copyright (C) 1992,1993 Rick Sladkey * Copyright (C) 1995,1996 Olaf Kirch */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "sunrpc.h" #include "netns.h" #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) # define RPCDBG_FACILITY RPCDBG_CALL #endif #define dprint_status(t) \ dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ __func__, t->tk_status) /* * All RPC clients are linked into this list */ 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_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); #if defined(CONFIG_SUNRPC_BACKCHANNEL) static void call_bc_transmit(struct rpc_task *task); #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 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 *rpc_encode_header(struct rpc_task *task); static __be32 *rpc_verify_header(struct rpc_task *task); static int rpc_ping(struct rpc_clnt *clnt); static void rpc_register_client(struct rpc_clnt *clnt) { struct net *net = rpc_net_ns(clnt); struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); list_add(&clnt->cl_clients, &sn->all_clients); spin_unlock(&sn->rpc_client_lock); } static void rpc_unregister_client(struct rpc_clnt *clnt) { struct net *net = rpc_net_ns(clnt); struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); list_del(&clnt->cl_clients); spin_unlock(&sn->rpc_client_lock); } static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) { rpc_remove_client_dir(clnt); } static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) { struct net *net = rpc_net_ns(clnt); struct super_block *pipefs_sb; pipefs_sb = rpc_get_sb_net(net); if (pipefs_sb) { __rpc_clnt_remove_pipedir(clnt); rpc_put_sb_net(net); } } static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, struct rpc_clnt *clnt) { static uint32_t clntid; const char *dir_name = clnt->cl_program->pipe_dir_name; char name[15]; struct dentry *dir, *dentry; dir = rpc_d_lookup_sb(sb, dir_name); if (dir == NULL) { pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); return dir; } for (;;) { snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); name[sizeof(name) - 1] = '\0'; dentry = rpc_create_client_dir(dir, name, clnt); if (!IS_ERR(dentry)) break; if (dentry == ERR_PTR(-EEXIST)) continue; printk(KERN_INFO "RPC: Couldn't create pipefs entry" " %s/%s, error %ld\n", dir_name, name, PTR_ERR(dentry)); break; } dput(dir); return dentry; } static int rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt) { struct dentry *dentry; if (clnt->cl_program->pipe_dir_name != NULL) { dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt); if (IS_ERR(dentry)) return PTR_ERR(dentry); } return 0; } static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) { if (clnt->cl_program->pipe_dir_name == NULL) return 1; switch (event) { case RPC_PIPEFS_MOUNT: if (clnt->cl_pipedir_objects.pdh_dentry != NULL) return 1; if (atomic_read(&clnt->cl_count) == 0) return 1; break; case RPC_PIPEFS_UMOUNT: if (clnt->cl_pipedir_objects.pdh_dentry == NULL) return 1; break; } return 0; } static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, struct super_block *sb) { struct dentry *dentry; int err = 0; switch (event) { case RPC_PIPEFS_MOUNT: dentry = rpc_setup_pipedir_sb(sb, clnt); if (!dentry) return -ENOENT; if (IS_ERR(dentry)) return PTR_ERR(dentry); break; case RPC_PIPEFS_UMOUNT: __rpc_clnt_remove_pipedir(clnt); break; default: printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); return -ENOTSUPP; } return err; } static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, struct super_block *sb) { int error = 0; for (;; clnt = clnt->cl_parent) { if (!rpc_clnt_skip_event(clnt, event)) error = __rpc_clnt_handle_event(clnt, event, sb); if (error || clnt == clnt->cl_parent) break; } return error; } static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) { struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); struct rpc_clnt *clnt; spin_lock(&sn->rpc_client_lock); list_for_each_entry(clnt, &sn->all_clients, cl_clients) { if (rpc_clnt_skip_event(clnt, event)) continue; spin_unlock(&sn->rpc_client_lock); return clnt; } spin_unlock(&sn->rpc_client_lock); return NULL; } static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr) { struct super_block *sb = ptr; struct rpc_clnt *clnt; int error = 0; while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { error = __rpc_pipefs_event(clnt, event, sb); if (error) break; } return error; } static struct notifier_block rpc_clients_block = { .notifier_call = rpc_pipefs_event, .priority = SUNRPC_PIPEFS_RPC_PRIO, }; int rpc_clients_notifier_register(void) { return rpc_pipefs_notifier_register(&rpc_clients_block); } void rpc_clients_notifier_unregister(void) { return rpc_pipefs_notifier_unregister(&rpc_clients_block); } static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt, struct rpc_xprt *xprt, const struct rpc_timeout *timeout) { struct rpc_xprt *old; spin_lock(&clnt->cl_lock); old = rcu_dereference_protected(clnt->cl_xprt, lockdep_is_held(&clnt->cl_lock)); if (!xprt_bound(xprt)) clnt->cl_autobind = 1; clnt->cl_timeout = timeout; rcu_assign_pointer(clnt->cl_xprt, xprt); spin_unlock(&clnt->cl_lock); return old; } static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) { clnt->cl_nodelen = strlcpy(clnt->cl_nodename, nodename, sizeof(clnt->cl_nodename)); } static int rpc_client_register(struct rpc_clnt *clnt, rpc_authflavor_t pseudoflavor, const char *client_name) { struct rpc_auth_create_args auth_args = { .pseudoflavor = pseudoflavor, .target_name = client_name, }; struct rpc_auth *auth; struct net *net = rpc_net_ns(clnt); struct super_block *pipefs_sb; int err; err = rpc_clnt_debugfs_register(clnt); if (err) return err; pipefs_sb = rpc_get_sb_net(net); if (pipefs_sb) { err = rpc_setup_pipedir(pipefs_sb, clnt); if (err) goto out; } rpc_register_client(clnt); if (pipefs_sb) rpc_put_sb_net(net); auth = rpcauth_create(&auth_args, clnt); if (IS_ERR(auth)) { dprintk("RPC: Couldn't create auth handle (flavor %u)\n", pseudoflavor); err = PTR_ERR(auth); goto err_auth; } return 0; err_auth: pipefs_sb = rpc_get_sb_net(net); rpc_unregister_client(clnt); __rpc_clnt_remove_pipedir(clnt); out: if (pipefs_sb) rpc_put_sb_net(net); rpc_clnt_debugfs_unregister(clnt); return err; } static DEFINE_IDA(rpc_clids); static int rpc_alloc_clid(struct rpc_clnt *clnt) { int clid; clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL); if (clid < 0) return clid; clnt->cl_clid = clid; return 0; } static void rpc_free_clid(struct rpc_clnt *clnt) { ida_simple_remove(&rpc_clids, clnt->cl_clid); } static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt, struct rpc_clnt *parent) { const struct rpc_program *program = args->program; const struct rpc_version *version; struct rpc_clnt *clnt = NULL; const struct rpc_timeout *timeout; const char *nodename = args->nodename; int err; /* sanity check the name before trying to print it */ dprintk("RPC: creating %s client for %s (xprt %p)\n", program->name, args->servername, xprt); err = rpciod_up(); if (err) goto out_no_rpciod; err = -EINVAL; if (args->version >= program->nrvers) goto out_err; version = program->version[args->version]; if (version == NULL) goto out_err; err = -ENOMEM; clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); if (!clnt) goto out_err; clnt->cl_parent = parent ? : clnt; err = rpc_alloc_clid(clnt); if (err) goto out_no_clid; clnt->cl_procinfo = version->procs; clnt->cl_maxproc = version->nrprocs; clnt->cl_prog = args->prognumber ? : program->number; clnt->cl_vers = version->number; clnt->cl_stats = program->stats; clnt->cl_metrics = rpc_alloc_iostats(clnt); rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 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); timeout = xprt->timeout; if (args->timeout != NULL) { memcpy(&clnt->cl_timeout_default, args->timeout, sizeof(clnt->cl_timeout_default)); timeout = &clnt->cl_timeout_default; } rpc_clnt_set_transport(clnt, xprt, timeout); clnt->cl_rtt = &clnt->cl_rtt_default; rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); atomic_set(&clnt->cl_count, 1); if (nodename == NULL) nodename = utsname()->nodename; /* save the nodename */ rpc_clnt_set_nodename(clnt, nodename); err = rpc_client_register(clnt, args->authflavor, args->client_name); if (err) goto out_no_path; if (parent) atomic_inc(&parent->cl_count); return clnt; out_no_path: rpc_free_iostats(clnt->cl_metrics); out_no_stats: rpc_free_clid(clnt); out_no_clid: kfree(clnt); out_err: rpciod_down(); out_no_rpciod: xprt_put(xprt); return ERR_PTR(err); } struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, struct rpc_xprt *xprt) { struct rpc_clnt *clnt = NULL; clnt = rpc_new_client(args, xprt, NULL); if (IS_ERR(clnt)) return clnt; if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { int err = rpc_ping(clnt); 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_AUTOBIND) clnt->cl_autobind = 1; if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) clnt->cl_noretranstimeo = 1; if (args->flags & RPC_CLNT_CREATE_DISCRTRY) clnt->cl_discrtry = 1; if (!(args->flags & RPC_CLNT_CREATE_QUIET)) clnt->cl_chatty = 1; return clnt; } EXPORT_SYMBOL_GPL(rpc_create_xprt); /** * 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 xprt_create xprtargs = { .net = args->net, .ident = args->protocol, .srcaddr = args->saddress, .dstaddr = args->address, .addrlen = args->addrsize, .servername = args->servername, .bc_xprt = args->bc_xprt, }; char servername[48]; if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; /* * If the caller chooses not to specify a hostname, whip * up a string representation of the passed-in address. */ if (xprtargs.servername == NULL) { struct sockaddr_un *sun = (struct sockaddr_un *)args->address; struct sockaddr_in *sin = (struct sockaddr_in *)args->address; struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)args->address; servername[0] = '\0'; switch (args->address->sa_family) { case AF_LOCAL: snprintf(servername, sizeof(servername), "%s", sun->sun_path); break; case AF_INET: snprintf(servername, sizeof(servername), "%pI4", &sin->sin_addr.s_addr); break; case AF_INET6: snprintf(servername, sizeof(servername), "%pI6", &sin6->sin6_addr); break; default: /* caller wants default server name, but * address family isn't recognized. */ return ERR_PTR(-EINVAL); } xprtargs.servername = servername; } xprt = xprt_create_transport(&xprtargs); if (IS_ERR(xprt)) return (struct rpc_clnt *)xprt; /* * 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; return rpc_create_xprt(args, xprt); } 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. */ static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, struct rpc_clnt *clnt) { struct rpc_xprt *xprt; struct rpc_clnt *new; int err; err = -ENOMEM; rcu_read_lock(); xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); rcu_read_unlock(); if (xprt == NULL) goto out_err; args->servername = xprt->servername; args->nodename = clnt->cl_nodename; new = rpc_new_client(args, xprt, clnt); if (IS_ERR(new)) { err = PTR_ERR(new); goto out_err; } /* Turn off autobind on clones */ new->cl_autobind = 0; new->cl_softrtry = clnt->cl_softrtry; new->cl_noretranstimeo = clnt->cl_noretranstimeo; new->cl_discrtry = clnt->cl_discrtry; new->cl_chatty = clnt->cl_chatty; return new; out_err: dprintk("RPC: %s: returned error %d\n", __func__, err); return ERR_PTR(err); } /** * rpc_clone_client - Clone an RPC client structure * * @clnt: RPC client whose parameters are copied * * Returns a fresh RPC client or an ERR_PTR. */ struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) { struct rpc_create_args args = { .program = clnt->cl_program, .prognumber = clnt->cl_prog, .version = clnt->cl_vers, .authflavor = clnt->cl_auth->au_flavor, }; return __rpc_clone_client(&args, clnt); } EXPORT_SYMBOL_GPL(rpc_clone_client); /** * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth * * @clnt: RPC client whose parameters are copied * @flavor: security flavor for new client * * Returns a fresh RPC client or an ERR_PTR. */ struct rpc_clnt * rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) { struct rpc_create_args args = { .program = clnt->cl_program, .prognumber = clnt->cl_prog, .version = clnt->cl_vers, .authflavor = flavor, }; return __rpc_clone_client(&args, clnt); } EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); /** * rpc_switch_client_transport: switch the RPC transport on the fly * @clnt: pointer to a struct rpc_clnt * @args: pointer to the new transport arguments * @timeout: pointer to the new timeout parameters * * This function allows the caller to switch the RPC transport for the * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS * server, for instance. It assumes that the caller has ensured that * there are no active RPC tasks by using some form of locking. * * Returns zero if "clnt" is now using the new xprt. Otherwise a * negative errno is returned, and "clnt" continues to use the old * xprt. */ int rpc_switch_client_transport(struct rpc_clnt *clnt, struct xprt_create *args, const struct rpc_timeout *timeout) { const struct rpc_timeout *old_timeo; rpc_authflavor_t pseudoflavor; struct rpc_xprt *xprt, *old; struct rpc_clnt *parent; int err; xprt = xprt_create_transport(args); if (IS_ERR(xprt)) { dprintk("RPC: failed to create new xprt for clnt %p\n", clnt); return PTR_ERR(xprt); } pseudoflavor = clnt->cl_auth->au_flavor; old_timeo = clnt->cl_timeout; old = rpc_clnt_set_transport(clnt, xprt, timeout); rpc_unregister_client(clnt); __rpc_clnt_remove_pipedir(clnt); rpc_clnt_debugfs_unregister(clnt); /* * A new transport was created. "clnt" therefore * becomes the root of a new cl_parent tree. clnt's * children, if it has any, still point to the old xprt. */ parent = clnt->cl_parent; clnt->cl_parent = clnt; /* * The old rpc_auth cache cannot be re-used. GSS * contexts in particular are between a single * client and server. */ err = rpc_client_register(clnt, pseudoflavor, NULL); if (err) goto out_revert; synchronize_rcu(); if (parent != clnt) rpc_release_client(parent); xprt_put(old); dprintk("RPC: replaced xprt for clnt %p\n", clnt); return 0; out_revert: rpc_clnt_set_transport(clnt, old, old_timeo); clnt->cl_parent = parent; rpc_client_register(clnt, pseudoflavor, NULL); xprt_put(xprt); dprintk("RPC: failed to switch xprt for clnt %p\n", clnt); return err; } EXPORT_SYMBOL_GPL(rpc_switch_client_transport); /* * Kill all tasks for the given client. * XXX: kill their descendants as well? */ void rpc_killall_tasks(struct rpc_clnt *clnt) { struct rpc_task *rovr; if (list_empty(&clnt->cl_tasks)) return; dprintk("RPC: killing all tasks for client %p\n", clnt); /* * Spin lock all_tasks to prevent changes... */ spin_lock(&clnt->cl_lock); list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { if (!RPC_IS_ACTIVATED(rovr)) continue; if (!(rovr->tk_flags & RPC_TASK_KILLED)) { rovr->tk_flags |= RPC_TASK_KILLED; rpc_exit(rovr, -EIO); if (RPC_IS_QUEUED(rovr)) rpc_wake_up_queued_task(rovr->tk_waitqueue, rovr); } } spin_unlock(&clnt->cl_lock); } EXPORT_SYMBOL_GPL(rpc_killall_tasks); /* * Properly shut down an RPC client, terminating all outstanding * requests. */ void rpc_shutdown_client(struct rpc_clnt *clnt) { might_sleep(); dprintk_rcu("RPC: shutting down %s client for %s\n", clnt->cl_program->name, rcu_dereference(clnt->cl_xprt)->servername); 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 struct rpc_clnt * rpc_free_client(struct rpc_clnt *clnt) { struct rpc_clnt *parent = NULL; dprintk_rcu("RPC: destroying %s client for %s\n", clnt->cl_program->name, rcu_dereference(clnt->cl_xprt)->servername); if (clnt->cl_parent != clnt) parent = clnt->cl_parent; rpc_clnt_debugfs_unregister(clnt); rpc_clnt_remove_pipedir(clnt); rpc_unregister_client(clnt); rpc_free_iostats(clnt->cl_metrics); clnt->cl_metrics = NULL; xprt_put(rcu_dereference_raw(clnt->cl_xprt)); rpciod_down(); rpc_free_clid(clnt); kfree(clnt); return parent; } /* * Free an RPC client */ static struct rpc_clnt * rpc_free_auth(struct rpc_clnt *clnt) { if (clnt->cl_auth == NULL) return rpc_free_client(clnt); /* * 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. */ atomic_inc(&clnt->cl_count); rpcauth_release(clnt->cl_auth); clnt->cl_auth = NULL; if (atomic_dec_and_test(&clnt->cl_count)) return rpc_free_client(clnt); return NULL; } /* * Release reference to the RPC client */ void rpc_release_client(struct rpc_clnt *clnt) { dprintk("RPC: rpc_release_client(%p)\n", clnt); do { if (list_empty(&clnt->cl_tasks)) wake_up(&destroy_wait); if (!atomic_dec_and_test(&clnt->cl_count)) break; clnt = rpc_free_auth(clnt); } while (clnt != NULL); } EXPORT_SYMBOL_GPL(rpc_release_client); /** * 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, const struct rpc_program *program, u32 vers) { struct rpc_create_args args = { .program = program, .prognumber = program->number, .version = vers, .authflavor = old->cl_auth->au_flavor, }; struct rpc_clnt *clnt; int err; clnt = __rpc_clone_client(&args, old); if (IS_ERR(clnt)) goto out; err = rpc_ping(clnt); if (err != 0) { rpc_shutdown_client(clnt); clnt = ERR_PTR(err); } out: return clnt; } EXPORT_SYMBOL_GPL(rpc_bind_new_program); void rpc_task_release_client(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; if (clnt != NULL) { /* Remove from client task list */ spin_lock(&clnt->cl_lock); list_del(&task->tk_task); spin_unlock(&clnt->cl_lock); task->tk_client = NULL; rpc_release_client(clnt); } } static void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) { if (clnt != NULL) { rpc_task_release_client(task); task->tk_client = clnt; atomic_inc(&clnt->cl_count); if (clnt->cl_softrtry) task->tk_flags |= RPC_TASK_SOFT; if (clnt->cl_noretranstimeo) task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; if (sk_memalloc_socks()) { struct rpc_xprt *xprt; rcu_read_lock(); xprt = rcu_dereference(clnt->cl_xprt); if (xprt->swapper) task->tk_flags |= RPC_TASK_SWAPPER; rcu_read_unlock(); } /* Add to the client's list of all tasks */ spin_lock(&clnt->cl_lock); list_add_tail(&task->tk_task, &clnt->cl_tasks); spin_unlock(&clnt->cl_lock); } } void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt) { rpc_task_release_client(task); rpc_task_set_client(task, clnt); } EXPORT_SYMBOL_GPL(rpc_task_reset_client); static void rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) { if (msg != NULL) { task->tk_msg.rpc_proc = msg->rpc_proc; task->tk_msg.rpc_argp = msg->rpc_argp; task->tk_msg.rpc_resp = msg->rpc_resp; if (msg->rpc_cred != NULL) task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); } } /* * 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, }; /** * 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; task = rpc_new_task(task_setup_data); if (IS_ERR(task)) goto out; rpc_task_set_client(task, task_setup_data->rpc_client); rpc_task_set_rpc_message(task, task_setup_data->rpc_message); if (task->tk_action == NULL) rpc_call_start(task); atomic_inc(&task->tk_count); rpc_execute(task); out: return task; } 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, const 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; WARN_ON_ONCE(flags & RPC_TASK_ASYNC); if (flags & RPC_TASK_ASYNC) { rpc_release_calldata(task_setup_data.callback_ops, task_setup_data.callback_data); return -EINVAL; } 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 * @tk_ops: RPC call ops * @data: user call data */ int rpc_call_async(struct rpc_clnt *clnt, const 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); #if defined(CONFIG_SUNRPC_BACKCHANNEL) /** * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run * rpc_execute against it * @req: RPC request * @tk_ops: RPC call ops */ struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, const struct rpc_call_ops *tk_ops) { struct rpc_task *task; struct xdr_buf *xbufp = &req->rq_snd_buf; struct rpc_task_setup task_setup_data = { .callback_ops = tk_ops, }; dprintk("RPC: rpc_run_bc_task req= %p\n", req); /* * Create an rpc_task to send the data */ task = rpc_new_task(&task_setup_data); if (IS_ERR(task)) { xprt_free_bc_request(req); goto out; } task->tk_rqstp = req; /* * Set up the xdr_buf length. * This also indicates that the buffer is XDR encoded already. */ xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + xbufp->tail[0].iov_len; task->tk_action = call_bc_transmit; atomic_inc(&task->tk_count); WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); rpc_execute(task); out: dprintk("RPC: rpc_run_bc_task: task= %p\n", task); return task; } #endif /* CONFIG_SUNRPC_BACKCHANNEL */ void rpc_call_start(struct rpc_task *task) { task->tk_action = call_start; } EXPORT_SYMBOL_GPL(rpc_call_start); /** * rpc_peeraddr - extract remote peer address from clnt's xprt * @clnt: RPC client structure * @buf: target buffer * @bufsize: 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; rcu_read_lock(); xprt = rcu_dereference(clnt->cl_xprt); bytes = xprt->addrlen; if (bytes > bufsize) bytes = bufsize; memcpy(buf, &xprt->addr, bytes); rcu_read_unlock(); return bytes; } EXPORT_SYMBOL_GPL(rpc_peeraddr); /** * rpc_peeraddr2str - return remote peer address in printable format * @clnt: RPC client structure * @format: address format * * NB: the lifetime of the memory referenced by the returned pointer is * the same as the rpc_xprt itself. As long as the caller uses this * pointer, it must hold the RCU read lock. */ const char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format) { struct rpc_xprt *xprt; xprt = rcu_dereference(clnt->cl_xprt); if (xprt->address_strings[format] != NULL) return xprt->address_strings[format]; else return "unprintable"; } EXPORT_SYMBOL_GPL(rpc_peeraddr2str); static const struct sockaddr_in rpc_inaddr_loopback = { .sin_family = AF_INET, .sin_addr.s_addr = htonl(INADDR_ANY), }; static const struct sockaddr_in6 rpc_in6addr_loopback = { .sin6_family = AF_INET6, .sin6_addr = IN6ADDR_ANY_INIT, }; /* * Try a getsockname() on a connected datagram socket. Using a * connected datagram socket prevents leaving a socket in TIME_WAIT. * This conserves the ephemeral port number space. * * Returns zero and fills in "buf" if successful; otherwise, a * negative errno is returned. */ static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, struct sockaddr *buf, int buflen) { struct socket *sock; int err; err = __sock_create(net, sap->sa_family, SOCK_DGRAM, IPPROTO_UDP, &sock, 1); if (err < 0) { dprintk("RPC: can't create UDP socket (%d)\n", err); goto out; } switch (sap->sa_family) { case AF_INET: err = kernel_bind(sock, (struct sockaddr *)&rpc_inaddr_loopback, sizeof(rpc_inaddr_loopback)); break; case AF_INET6: err = kernel_bind(sock, (struct sockaddr *)&rpc_in6addr_loopback, sizeof(rpc_in6addr_loopback)); break; default: err = -EAFNOSUPPORT; goto out; } if (err < 0) { dprintk("RPC: can't bind UDP socket (%d)\n", err); goto out_release; } err = kernel_connect(sock, sap, salen, 0); if (err < 0) { dprintk("RPC: can't connect UDP socket (%d)\n", err); goto out_release; } err = kernel_getsockname(sock, buf, &buflen); if (err < 0) { dprintk("RPC: getsockname failed (%d)\n", err); goto out_release; } err = 0; if (buf->sa_family == AF_INET6) { struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; sin6->sin6_scope_id = 0; } dprintk("RPC: %s succeeded\n", __func__); out_release: sock_release(sock); out: return err; } /* * Scraping a connected socket failed, so we don't have a useable * local address. Fallback: generate an address that will prevent * the server from calling us back. * * Returns zero and fills in "buf" if successful; otherwise, a * negative errno is returned. */ static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) { switch (family) { case AF_INET: if (buflen < sizeof(rpc_inaddr_loopback)) return -EINVAL; memcpy(buf, &rpc_inaddr_loopback, sizeof(rpc_inaddr_loopback)); break; case AF_INET6: if (buflen < sizeof(rpc_in6addr_loopback)) return -EINVAL; memcpy(buf, &rpc_in6addr_loopback, sizeof(rpc_in6addr_loopback)); default: dprintk("RPC: %s: address family not supported\n", __func__); return -EAFNOSUPPORT; } dprintk("RPC: %s: succeeded\n", __func__); return 0; } /** * rpc_localaddr - discover local endpoint address for an RPC client * @clnt: RPC client structure * @buf: target buffer * @buflen: size of target buffer, in bytes * * Returns zero and fills in "buf" and "buflen" if successful; * otherwise, a negative errno is returned. * * This works even if the underlying transport is not currently connected, * or if the upper layer never previously provided a source address. * * The result of this function call is transient: multiple calls in * succession may give different results, depending on how local * networking configuration changes over time. */ int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) { struct sockaddr_storage address; struct sockaddr *sap = (struct sockaddr *)&address; struct rpc_xprt *xprt; struct net *net; size_t salen; int err; rcu_read_lock(); xprt = rcu_dereference(clnt->cl_xprt); salen = xprt->addrlen; memcpy(sap, &xprt->addr, salen); net = get_net(xprt->xprt_net); rcu_read_unlock(); rpc_set_port(sap, 0); err = rpc_sockname(net, sap, salen, buf, buflen); put_net(net); if (err != 0) /* Couldn't discover local address, return ANYADDR */ return rpc_anyaddr(sap->sa_family, buf, buflen); return 0; } EXPORT_SYMBOL_GPL(rpc_localaddr); void rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) { struct rpc_xprt *xprt; rcu_read_lock(); xprt = rcu_dereference(clnt->cl_xprt); if (xprt->ops->set_buffer_size) xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); rcu_read_unlock(); } EXPORT_SYMBOL_GPL(rpc_setbufsize); /** * rpc_protocol - Get transport protocol number for an RPC client * @clnt: RPC client to query * */ int rpc_protocol(struct rpc_clnt *clnt) { int protocol; rcu_read_lock(); protocol = rcu_dereference(clnt->cl_xprt)->prot; rcu_read_unlock(); return protocol; } EXPORT_SYMBOL_GPL(rpc_protocol); /** * rpc_net_ns - Get the network namespace for this RPC client * @clnt: RPC client to query * */ struct net *rpc_net_ns(struct rpc_clnt *clnt) { struct net *ret; rcu_read_lock(); ret = rcu_dereference(clnt->cl_xprt)->xprt_net; rcu_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(rpc_net_ns); /** * rpc_max_payload - Get maximum payload size for a transport, in bytes * @clnt: RPC client to query * * 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) { size_t ret; rcu_read_lock(); ret = rcu_dereference(clnt->cl_xprt)->max_payload; rcu_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(rpc_max_payload); /** * rpc_get_timeout - Get timeout for transport in units of HZ * @clnt: RPC client to query */ unsigned long rpc_get_timeout(struct rpc_clnt *clnt) { unsigned long ret; rcu_read_lock(); ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval; rcu_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(rpc_get_timeout); /** * 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) { rcu_read_lock(); xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); rcu_read_unlock(); } } EXPORT_SYMBOL_GPL(rpc_force_rebind); /* * Restart an (async) RPC call from the call_prepare state. * Usually called from within the exit handler. */ int rpc_restart_call_prepare(struct rpc_task *task) { if (RPC_ASSASSINATED(task)) return 0; task->tk_action = call_start; task->tk_status = 0; if (task->tk_ops->rpc_call_prepare != NULL) task->tk_action = rpc_prepare_task; return 1; } EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); /* * Restart an (async) RPC call. Usually called from within the * exit handler. */ int rpc_restart_call(struct rpc_task *task) { if (RPC_ASSASSINATED(task)) return 0; task->tk_action = call_start; task->tk_status = 0; return 1; } EXPORT_SYMBOL_GPL(rpc_restart_call); #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) const char *rpc_proc_name(const struct rpc_task *task) { const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; if (proc) { if (proc->p_name) return proc->p_name; else return "NULL"; } else return "no proc"; } #endif /* * 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 %s (%s)\n", task->tk_pid, clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), (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); task->tk_status = 0; task->tk_action = call_reserveresult; xprt_reserve(task); } static void call_retry_reserve(struct rpc_task *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_refresh; return; } printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", __func__, 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", __func__, status); xprt_release(task); } switch (status) { case -ENOMEM: rpc_delay(task, HZ >> 2); case -EAGAIN: /* woken up; retry */ task->tk_action = call_retry_reserve; return; case -EIO: /* probably a shutdown */ break; default: printk(KERN_ERR "%s: unrecognized error %d, exiting\n", __func__, status); break; } rpc_exit(task, status); } /* * 1c. Retry reserving an RPC call slot */ static void call_retry_reserve(struct rpc_task *task) { dprint_status(task); task->tk_status = 0; task->tk_action = call_reserveresult; xprt_retry_reserve(task); } /* * 2. Bind and/or refresh the credentials */ 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); } /* * 2a. 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_refresh; switch (status) { case 0: if (rpcauth_uptodatecred(task)) { task->tk_action = call_allocate; return; } /* Use rate-limiting and a max number of retries if refresh * had status 0 but failed to update the cred. */ case -ETIMEDOUT: rpc_delay(task, 3*HZ); case -EAGAIN: status = -EACCES; case -EKEYEXPIRED: if (!task->tk_cred_retry) break; task->tk_cred_retry--; dprintk("RPC: %5u %s: retry refresh creds\n", task->tk_pid, __func__); return; } dprintk("RPC: %5u %s: refresh creds failed with error %d\n", task->tk_pid, __func__, status); rpc_exit(task, status); } /* * 2b. 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_rqstp->rq_cred->cr_auth->au_cslack; struct rpc_rqst *req = task->tk_rqstp; struct rpc_xprt *xprt = req->rq_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) || !fatal_signal_pending(current)) { 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; task->tk_rqstp->rq_bytes_sent = 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 rpc_xdr_encode(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; kxdreproc_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); p = rpc_encode_header(task); if (p == NULL) { printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); rpc_exit(task, -EIO); return; } encode = task->tk_msg.rpc_proc->p_encode; if (encode == NULL) return; task->tk_status = rpcauth_wrap_req(task, encode, req, p, task->tk_msg.rpc_argp); } /* * 4. Get the server port number if not yet set */ static void call_bind(struct rpc_task *task) { struct rpc_xprt *xprt = task->tk_rqstp->rq_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; } trace_rpc_bind_status(task); switch (task->tk_status) { case -ENOMEM: dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); rpc_delay(task, HZ >> 2); 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; } if (task->tk_rebind_retry == 0) break; task->tk_rebind_retry--; 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 unrecognized remote rpcbind service\n", task->tk_pid); break; case -EPROTONOSUPPORT: dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", task->tk_pid); goto retry_timeout; case -ECONNREFUSED: /* connection problems */ case -ECONNRESET: case -ECONNABORTED: case -ENOTCONN: case -EHOSTDOWN: case -EHOSTUNREACH: case -ENETUNREACH: case -ENOBUFS: case -EPIPE: dprintk("RPC: %5u remote rpcbind unreachable: %d\n", task->tk_pid, task->tk_status); if (!RPC_IS_SOFTCONN(task)) { rpc_delay(task, 5*HZ); goto retry_timeout; } status = task->tk_status; break; default: dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", task->tk_pid, -task->tk_status); } rpc_exit(task, status); return; retry_timeout: task->tk_status = 0; 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_rqstp->rq_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; if (task->tk_flags & RPC_TASK_NOCONNECT) { rpc_exit(task, -ENOTCONN); 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); trace_rpc_connect_status(task, status); task->tk_status = 0; switch (status) { case -ECONNREFUSED: case -ECONNRESET: case -ECONNABORTED: case -ENETUNREACH: case -EHOSTUNREACH: case -EADDRINUSE: case -ENOBUFS: case -EPIPE: if (RPC_IS_SOFTCONN(task)) break; /* retry with existing socket, after a delay */ rpc_delay(task, 3*HZ); case -EAGAIN: /* Check for timeouts before looping back to call_bind */ case -ETIMEDOUT: task->tk_action = call_timeout; return; case 0: clnt->cl_stats->netreconn++; task->tk_action = call_transmit; return; } rpc_exit(task, status); } /* * 5. Transmit the RPC request, and wait for reply */ static void call_transmit(struct rpc_task *task) { int is_retrans = RPC_WAS_SENT(task); dprint_status(task); task->tk_action = call_status; if (task->tk_status < 0) return; if (!xprt_prepare_transmit(task)) return; task->tk_action = call_transmit_status; /* Encode here so that rpcsec_gss can use correct sequence number. */ if (rpc_task_need_encode(task)) { rpc_xdr_encode(task); /* Did the encode result in an error condition? */ if (task->tk_status != 0) { /* Was the error nonfatal? */ if (task->tk_status == -EAGAIN) rpc_delay(task, HZ >> 4); else rpc_exit(task, task->tk_status); return; } } xprt_transmit(task); if (task->tk_status < 0) return; if (is_retrans) task->tk_client->cl_stats->rpcretrans++; /* * 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 (rpc_reply_expected(task)) return; task->tk_action = rpc_exit_task; rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task); } /* * 5a. Handle cleanup after a transmission */ static void call_transmit_status(struct rpc_task *task) { task->tk_action = call_status; /* * Common case: success. Force the compiler to put this * test first. */ if (task->tk_status == 0) { xprt_end_transmit(task); rpc_task_force_reencode(task); return; } switch (task->tk_status) { case -EAGAIN: break; default: dprint_status(task); xprt_end_transmit(task); rpc_task_force_reencode(task); break; /* * Special cases: if we've been waiting on the * socket's write_space() callback, or if the * socket just returned a connection error, * then hold onto the transport lock. */ case -ECONNREFUSED: case -EHOSTDOWN: case -EHOSTUNREACH: case -ENETUNREACH: case -EPERM: if (RPC_IS_SOFTCONN(task)) { xprt_end_transmit(task); rpc_exit(task, task->tk_status); break; } case -ECONNRESET: case -ECONNABORTED: case -EADDRINUSE: case -ENOTCONN: case -ENOBUFS: case -EPIPE: rpc_task_force_reencode(task); } } #if defined(CONFIG_SUNRPC_BACKCHANNEL) /* * 5b. Send the backchannel RPC reply. On error, drop the reply. In * addition, disconnect on connectivity errors. */ static void call_bc_transmit(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; if (!xprt_prepare_transmit(task)) { /* * Could not reserve the transport. Try again after the * transport is released. */ task->tk_status = 0; task->tk_action = call_bc_transmit; return; } task->tk_action = rpc_exit_task; if (task->tk_status < 0) { printk(KERN_NOTICE "RPC: Could not send backchannel reply " "error: %d\n", task->tk_status); return; } xprt_transmit(task); xprt_end_transmit(task); dprint_status(task); switch (task->tk_status) { case 0: /* Success */ break; case -EHOSTDOWN: case -EHOSTUNREACH: case -ENETUNREACH: case -ETIMEDOUT: /* * Problem reaching the server. Disconnect and let the * forechannel reestablish the connection. The server will * have to retransmit the backchannel request and we'll * reprocess it. Since these ops are idempotent, there's no * need to cache our reply at this time. */ printk(KERN_NOTICE "RPC: Could not send backchannel reply " "error: %d\n", task->tk_status); xprt_conditional_disconnect(req->rq_xprt, req->rq_connect_cookie); break; default: /* * We were unable to reply and will have to drop the * request. The server should reconnect and retransmit. */ WARN_ON_ONCE(task->tk_status == -EAGAIN); printk(KERN_NOTICE "RPC: Could not send backchannel reply " "error: %d\n", task->tk_status); break; } rpc_wake_up_queued_task(&req->rq_xprt->pending, task); } #endif /* CONFIG_SUNRPC_BACKCHANNEL */ /* * 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_reply_bytes_recvd > 0 && !req->rq_bytes_sent) task->tk_status = req->rq_reply_bytes_recvd; dprint_status(task); status = task->tk_status; if (status >= 0) { task->tk_action = call_decode; return; } trace_rpc_call_status(task); task->tk_status = 0; switch(status) { case -EHOSTDOWN: case -EHOSTUNREACH: case -ENETUNREACH: case -EPERM: if (RPC_IS_SOFTCONN(task)) { rpc_exit(task, status); break; } /* * 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_flags & RPC_TASK_NO_RETRANS_TIMEOUT) && task->tk_client->cl_discrtry) xprt_conditional_disconnect(req->rq_xprt, req->rq_connect_cookie); break; case -ECONNREFUSED: case -ECONNRESET: case -ECONNABORTED: rpc_force_rebind(clnt); case -EADDRINUSE: case -ENOBUFS: rpc_delay(task, 3*HZ); case -EPIPE: case -ENOTCONN: 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: if (clnt->cl_chatty) printk("%s: RPC call returned error %d\n", clnt->cl_program->name, -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_SOFTCONN(task)) { rpc_exit(task, -ETIMEDOUT); return; } if (RPC_IS_SOFT(task)) { if (clnt->cl_chatty) { rcu_read_lock(); printk(KERN_NOTICE "%s: server %s not responding, timed out\n", clnt->cl_program->name, rcu_dereference(clnt->cl_xprt)->servername); rcu_read_unlock(); } if (task->tk_flags & RPC_TASK_TIMEOUT) rpc_exit(task, -ETIMEDOUT); else rpc_exit(task, -EIO); return; } if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { task->tk_flags |= RPC_CALL_MAJORSEEN; if (clnt->cl_chatty) { rcu_read_lock(); printk(KERN_NOTICE "%s: server %s not responding, still trying\n", clnt->cl_program->name, rcu_dereference(clnt->cl_xprt)->servername); rcu_read_unlock(); } } rpc_force_rebind(clnt); /* * Did our request time out due to an RPCSEC_GSS out-of-sequence * event? RFC2203 requires the server to drop all such requests. */ rpcauth_invalcred(task); retry: 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; kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; __be32 *p; dprint_status(task); if (task->tk_flags & RPC_CALL_MAJORSEEN) { if (clnt->cl_chatty) { rcu_read_lock(); printk(KERN_NOTICE "%s: server %s OK\n", clnt->cl_program->name, rcu_dereference(clnt->cl_xprt)->servername); rcu_read_unlock(); } task->tk_flags &= ~RPC_CALL_MAJORSEEN; } /* * Ensure that we see all writes made by xprt_complete_rqst() * before it changed req->rq_reply_bytes_recvd. */ 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); if (req->rq_rcv_buf.len < 12) { if (!RPC_IS_SOFT(task)) { task->tk_action = call_bind; goto out_retry; } dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", clnt->cl_program->name, task->tk_status); task->tk_action = call_timeout; goto out_retry; } p = rpc_verify_header(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: task->tk_status = 0; /* Note: rpc_verify_header() may have freed the RPC slot */ if (task->tk_rqstp == req) { req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; if (task->tk_client->cl_discrtry) xprt_conditional_disconnect(req->rq_xprt, req->rq_connect_cookie); } } static __be32 * rpc_encode_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(req->rq_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; } static __be32 * rpc_verify_header(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; 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, __func__, task->tk_rqstp->rq_rcv_buf.len); error = -EIO; goto out_err; } 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, __func__, n); error = -EIO; 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, __func__); error = -EPROTONOSUPPORT; goto out_err; default: dprintk("RPC: %5u %s: RPC call rejected, " "unknown error: %x\n", task->tk_pid, __func__, n); error = -EIO; goto out_err; } 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, __func__); rpcauth_invalcred(task); /* Ensure we obtain a new XID! */ xprt_release(task); task->tk_action = call_reserve; 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, __func__); task->tk_action = call_bind; goto out_retry; case RPC_AUTH_TOOWEAK: rcu_read_lock(); printk(KERN_NOTICE "RPC: server %s requires stronger " "authentication.\n", rcu_dereference(clnt->cl_xprt)->servername); rcu_read_unlock(); break; default: dprintk("RPC: %5u %s: unknown auth error: %x\n", task->tk_pid, __func__, n); error = -EIO; } dprintk("RPC: %5u %s: call rejected %d\n", task->tk_pid, __func__, n); goto out_err; } p = rpcauth_checkverf(task, p); if (IS_ERR(p)) { error = PTR_ERR(p); dprintk("RPC: %5u %s: auth check failed with %d\n", task->tk_pid, __func__, error); 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_rcu("RPC: %5u %s: program %u is unsupported " "by server %s\n", task->tk_pid, __func__, (unsigned int)clnt->cl_prog, rcu_dereference(clnt->cl_xprt)->servername); error = -EPFNOSUPPORT; goto out_err; case RPC_PROG_MISMATCH: dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported " "by server %s\n", task->tk_pid, __func__, (unsigned int)clnt->cl_prog, (unsigned int)clnt->cl_vers, rcu_dereference(clnt->cl_xprt)->servername); error = -EPROTONOSUPPORT; goto out_err; case RPC_PROC_UNAVAIL: dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, " "version %u on server %s\n", task->tk_pid, __func__, rpc_proc_name(task), clnt->cl_prog, clnt->cl_vers, rcu_dereference(clnt->cl_xprt)->servername); error = -EOPNOTSUPP; goto out_err; case RPC_GARBAGE_ARGS: dprintk("RPC: %5u %s: server saw garbage\n", task->tk_pid, __func__); break; /* retry */ default: dprintk("RPC: %5u %s: server accept status: %x\n", task->tk_pid, __func__, n); /* Also retry */ } out_garbage: clnt->cl_stats->rpcgarbage++; if (task->tk_garb_retry) { task->tk_garb_retry--; dprintk("RPC: %5u %s: retrying\n", task->tk_pid, __func__); task->tk_action = call_bind; out_retry: return ERR_PTR(-EAGAIN); } out_err: rpc_exit(task, error); dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, __func__, error); return ERR_PTR(error); out_overflow: dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, __func__); goto out_garbage; } static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) { } static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, 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) { 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, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 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); #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) static void rpc_show_header(void) { printk(KERN_INFO "-pid- flgs status -client- --rqstp- " "-timeout ---ops--\n"); } static void rpc_show_task(const struct rpc_clnt *clnt, const struct rpc_task *task) { const char *rpc_waitq = "none"; if (RPC_IS_QUEUED(task)) rpc_waitq = rpc_qname(task->tk_waitqueue); printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", task->tk_pid, task->tk_flags, task->tk_status, clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), task->tk_action, rpc_waitq); } void rpc_show_tasks(struct net *net) { struct rpc_clnt *clnt; struct rpc_task *task; int header = 0; struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); spin_lock(&sn->rpc_client_lock); list_for_each_entry(clnt, &sn->all_clients, cl_clients) { spin_lock(&clnt->cl_lock); list_for_each_entry(task, &clnt->cl_tasks, tk_task) { if (!header) { rpc_show_header(); header++; } rpc_show_task(clnt, task); } spin_unlock(&clnt->cl_lock); } spin_unlock(&sn->rpc_client_lock); } #endif