diff options
Diffstat (limited to '')
| -rw-r--r-- | net/sunrpc/clnt.c | 2896 |
1 files changed, 2896 insertions, 0 deletions
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c new file mode 100644 index 000000000..0d7d149b1 --- /dev/null +++ b/net/sunrpc/clnt.c @@ -0,0 +1,2896 @@ +/* + * 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 <jrs@world.std.com> + * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> + */ + + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kallsyms.h> +#include <linux/mm.h> +#include <linux/namei.h> +#include <linux/mount.h> +#include <linux/slab.h> +#include <linux/rcupdate.h> +#include <linux/utsname.h> +#include <linux/workqueue.h> +#include <linux/in.h> +#include <linux/in6.h> +#include <linux/un.h> + +#include <linux/sunrpc/clnt.h> +#include <linux/sunrpc/addr.h> +#include <linux/sunrpc/rpc_pipe_fs.h> +#include <linux/sunrpc/metrics.h> +#include <linux/sunrpc/bc_xprt.h> +#include <trace/events/sunrpc.h> + +#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; + + 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 0; +} + +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; + + rpc_clnt_debugfs_register(clnt); + + 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); + +void rpc_cleanup_clids(void) +{ + ida_destroy(&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_switch *xps, + 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); + xprt_iter_init(&clnt->cl_xpi, xps); + xprt_switch_put(xps); + + 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_switch_put(xps); + xprt_put(xprt); + return ERR_PTR(err); +} + +static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, + struct rpc_xprt *xprt) +{ + struct rpc_clnt *clnt = NULL; + struct rpc_xprt_switch *xps; + + if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) { + WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); + xps = args->bc_xprt->xpt_bc_xps; + xprt_switch_get(xps); + } else { + xps = xprt_switch_alloc(xprt, GFP_KERNEL); + if (xps == NULL) { + xprt_put(xprt); + return ERR_PTR(-ENOMEM); + } + if (xprt->bc_xprt) { + xprt_switch_get(xps); + xprt->bc_xprt->xpt_bc_xps = xps; + } + } + clnt = rpc_new_client(args, xps, 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; +} + +/** + * 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->bc_xprt) { + WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); + xprt = args->bc_xprt->xpt_bc_xprt; + if (xprt) { + xprt_get(xprt); + return rpc_create_xprt(args, xprt); + } + } + + 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_switch *xps; + struct rpc_xprt *xprt; + struct rpc_clnt *new; + int err; + + err = -ENOMEM; + rcu_read_lock(); + xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); + xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); + rcu_read_unlock(); + if (xprt == NULL || xps == NULL) { + xprt_put(xprt); + xprt_switch_put(xps); + goto out_err; + } + args->servername = xprt->servername; + args->nodename = clnt->cl_nodename; + + new = rpc_new_client(args, xps, 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_switch *xps, *oldxps; + 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); + } + + xps = xprt_switch_alloc(xprt, GFP_KERNEL); + if (xps == NULL) { + xprt_put(xprt); + return -ENOMEM; + } + + pseudoflavor = clnt->cl_auth->au_flavor; + + old_timeo = clnt->cl_timeout; + old = rpc_clnt_set_transport(clnt, xprt, timeout); + oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps); + + 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_switch_put(oldxps); + xprt_put(old); + dprintk("RPC: replaced xprt for clnt %p\n", clnt); + return 0; + +out_revert: + xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps); + rpc_clnt_set_transport(clnt, old, old_timeo); + clnt->cl_parent = parent; + rpc_client_register(clnt, pseudoflavor, NULL); + xprt_switch_put(xps); + xprt_put(xprt); + dprintk("RPC: failed to switch xprt for clnt %p\n", clnt); + return err; +} +EXPORT_SYMBOL_GPL(rpc_switch_client_transport); + +static +int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi) +{ + struct rpc_xprt_switch *xps; + + rcu_read_lock(); + xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); + rcu_read_unlock(); + if (xps == NULL) + return -EAGAIN; + xprt_iter_init_listall(xpi, xps); + xprt_switch_put(xps); + return 0; +} + +/** + * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports + * @clnt: pointer to client + * @fn: function to apply + * @data: void pointer to function data + * + * Iterates through the list of RPC transports currently attached to the + * client and applies the function fn(clnt, xprt, data). + * + * On error, the iteration stops, and the function returns the error value. + */ +int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, + int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *), + void *data) +{ + struct rpc_xprt_iter xpi; + int ret; + + ret = rpc_clnt_xprt_iter_init(clnt, &xpi); + if (ret) + return ret; + for (;;) { + struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); + + if (!xprt) + break; + ret = fn(clnt, xprt, data); + xprt_put(xprt); + if (ret < 0) + break; + } + xprt_iter_destroy(&xpi); + return ret; +} +EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt); + +/* + * 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)); + xprt_iter_destroy(&clnt->cl_xpi); + 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_transport(struct rpc_task *task) +{ + struct rpc_xprt *xprt = task->tk_xprt; + + if (xprt) { + task->tk_xprt = NULL; + xprt_put(xprt); + } +} +EXPORT_SYMBOL_GPL(rpc_task_release_transport); + +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); + } + rpc_task_release_transport(task); +} + +static +void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) +{ + if (!task->tk_xprt) + task->tk_xprt = xprt_iter_get_next(&clnt->cl_xpi); +} + +static +void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) +{ + + if (clnt != NULL) { + rpc_task_set_transport(task, clnt); + 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 (atomic_read(&clnt->cl_swapper)) + task->tk_flags |= RPC_TASK_SWAPPER; + /* 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); + } +} + +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); + + 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); + 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 + */ +struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req) +{ + struct rpc_task *task; + struct xdr_buf *xbufp = &req->rq_snd_buf; + struct rpc_task_setup task_setup_data = { + .callback_ops = &rpc_default_ops, + .flags = RPC_TASK_SOFTCONN, + }; + + 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); + 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); + + 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) +{ + 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); + 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)); + break; + 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); + 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_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_max_bc_payload - Get maximum backchannel payload size, in bytes + * @clnt: RPC client to query + */ +size_t rpc_max_bc_payload(struct rpc_clnt *clnt) +{ + struct rpc_xprt *xprt; + size_t ret; + + rcu_read_lock(); + xprt = rcu_dereference(clnt->cl_xprt); + ret = xprt->ops->bc_maxpayload(xprt); + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(rpc_max_bc_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) { + 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); + +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"; +} + +/* + * 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; + int idx = task->tk_msg.rpc_proc->p_statidx; + + trace_rpc_request(task); + 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 (version might not be valid for ping) */ + if (clnt->cl_program->version[clnt->cl_vers]) + clnt->cl_program->version[clnt->cl_vers]->counts[idx]++; + clnt->cl_stats->rpccnt++; + task->tk_action = call_reserve; + rpc_task_set_transport(task, clnt); +} + +/* + * 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); + /* fall through */ + 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. + */ + /* fall through */ + case -ETIMEDOUT: + rpc_delay(task, 3*HZ); + /* fall through */ + case -EAGAIN: + status = -EACCES; + /* fall through */ + 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; + const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; + int status; + + 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; + + status = xprt->ops->buf_alloc(task); + xprt_inject_disconnect(xprt); + if (status == 0) + return; + if (status != -ENOMEM) { + rpc_exit(task, status); + 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; +} + +/* + * 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); + + xdr_buf_init(&req->rq_snd_buf, + req->rq_buffer, + req->rq_callsize); + xdr_buf_init(&req->rq_rcv_buf, + req->rq_rbuffer, + 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 -ENETDOWN: + 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); + task->tk_status = 0; + switch (status) { + case -ECONNREFUSED: + /* A positive refusal suggests a rebind is needed. */ + if (RPC_IS_SOFTCONN(task)) + break; + if (clnt->cl_autobind) { + rpc_force_rebind(clnt); + task->tk_action = call_bind; + return; + } + /* fall through */ + case -ECONNRESET: + case -ECONNABORTED: + case -ENETDOWN: + case -ENETUNREACH: + case -EHOSTUNREACH: + case -EADDRINUSE: + case -ENOBUFS: + case -EPIPE: + xprt_conditional_disconnect(task->tk_rqstp->rq_xprt, + task->tk_rqstp->rq_connect_cookie); + if (RPC_IS_SOFTCONN(task)) + break; + /* retry with existing socket, after a delay */ + rpc_delay(task, 3*HZ); + /* fall through */ + 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) +{ + struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; + task->tk_action = call_status; + + /* + * Common case: success. Force the compiler to put this + * test first. Or, if any error and xprt_close_wait, + * release the xprt lock so the socket can close. + */ + if (task->tk_status == 0 || xprt_close_wait(xprt)) { + xprt_end_transmit(task); + rpc_task_force_reencode(task); + return; + } + + switch (task->tk_status) { + case -EAGAIN: + case -ENOBUFS: + 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 -ENETDOWN: + case -EHOSTUNREACH: + case -ENETUNREACH: + case -EPERM: + if (RPC_IS_SOFTCONN(task)) { + xprt_end_transmit(task); + if (!task->tk_msg.rpc_proc->p_proc) + trace_xprt_ping(task->tk_xprt, + task->tk_status); + rpc_exit(task, task->tk_status); + break; + } + /* fall through */ + case -ECONNRESET: + case -ECONNABORTED: + case -EADDRINUSE: + case -ENOTCONN: + 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)) + goto out_retry; + + if (task->tk_status < 0) { + printk(KERN_NOTICE "RPC: Could not send backchannel reply " + "error: %d\n", task->tk_status); + goto out_done; + } + if (req->rq_connect_cookie != req->rq_xprt->connect_cookie) + req->rq_bytes_sent = 0; + + xprt_transmit(task); + + if (task->tk_status == -EAGAIN) + goto out_nospace; + + xprt_end_transmit(task); + dprint_status(task); + switch (task->tk_status) { + case 0: + /* Success */ + case -ENETDOWN: + case -EHOSTDOWN: + case -EHOSTUNREACH: + case -ENETUNREACH: + case -ECONNRESET: + case -ECONNREFUSED: + case -EADDRINUSE: + case -ENOTCONN: + case -EPIPE: + break; + 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); +out_done: + task->tk_action = rpc_exit_task; + return; +out_nospace: + req->rq_connect_cookie = req->rq_xprt->connect_cookie; +out_retry: + task->tk_status = 0; +} +#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 (!task->tk_msg.rpc_proc->p_proc) + trace_xprt_ping(task->tk_xprt, task->tk_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 -ENETDOWN: + 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); + /* fall through */ + case -ETIMEDOUT: + task->tk_action = call_timeout; + break; + case -ECONNREFUSED: + case -ECONNRESET: + case -ECONNABORTED: + rpc_force_rebind(clnt); + /* fall through */ + case -EADDRINUSE: + rpc_delay(task, 3*HZ); + /* fall through */ + case -EPIPE: + case -ENOTCONN: + task->tk_action = call_bind; + break; + case -ENOBUFS: + rpc_delay(task, HZ>>2); + /* fall through */ + 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) { + printk(KERN_NOTICE "%s: server %s not responding, timed out\n", + clnt->cl_program->name, + task->tk_xprt->servername); + } + 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) { + printk(KERN_NOTICE "%s: server %s not responding, still trying\n", + clnt->cl_program->name, + task->tk_xprt->servername); + } + } + 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) { + printk(KERN_NOTICE "%s: server %s OK\n", + clnt->cl_program->name, + task->tk_xprt->servername); + } + 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: + printk(KERN_NOTICE "RPC: server %s requires stronger " + "authentication.\n", + task->tk_xprt->servername); + 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("RPC: %5u %s: program %u is unsupported " + "by server %s\n", task->tk_pid, __func__, + (unsigned int)clnt->cl_prog, + task->tk_xprt->servername); + 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, __func__, + (unsigned int)clnt->cl_prog, + (unsigned int)clnt->cl_vers, + task->tk_xprt->servername); + error = -EPROTONOSUPPORT; + goto out_err; + case RPC_PROC_UNAVAIL: + dprintk("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, + task->tk_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(struct rpc_rqst *rqstp, struct xdr_stream *xdr, + const void *obj) +{ +} + +static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, + void *obj) +{ + return 0; +} + +static const 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; +} + +static +struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, + struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, + const struct rpc_call_ops *ops, void *data) +{ + struct rpc_message msg = { + .rpc_proc = &rpcproc_null, + .rpc_cred = cred, + }; + struct rpc_task_setup task_setup_data = { + .rpc_client = clnt, + .rpc_xprt = xprt, + .rpc_message = &msg, + .callback_ops = (ops != NULL) ? ops : &rpc_default_ops, + .callback_data = data, + .flags = flags, + }; + + return rpc_run_task(&task_setup_data); +} + +struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) +{ + return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); +} +EXPORT_SYMBOL_GPL(rpc_call_null); + +struct rpc_cb_add_xprt_calldata { + struct rpc_xprt_switch *xps; + struct rpc_xprt *xprt; +}; + +static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) +{ + struct rpc_cb_add_xprt_calldata *data = calldata; + + if (task->tk_status == 0) + rpc_xprt_switch_add_xprt(data->xps, data->xprt); +} + +static void rpc_cb_add_xprt_release(void *calldata) +{ + struct rpc_cb_add_xprt_calldata *data = calldata; + + xprt_put(data->xprt); + xprt_switch_put(data->xps); + kfree(data); +} + +static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { + .rpc_call_done = rpc_cb_add_xprt_done, + .rpc_release = rpc_cb_add_xprt_release, +}; + +/** + * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt + * @clnt: pointer to struct rpc_clnt + * @xps: pointer to struct rpc_xprt_switch, + * @xprt: pointer struct rpc_xprt + * @dummy: unused + */ +int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, + struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, + void *dummy) +{ + struct rpc_cb_add_xprt_calldata *data; + struct rpc_cred *cred; + struct rpc_task *task; + + data = kmalloc(sizeof(*data), GFP_NOFS); + if (!data) + return -ENOMEM; + data->xps = xprt_switch_get(xps); + data->xprt = xprt_get(xprt); + + cred = authnull_ops.lookup_cred(NULL, NULL, 0); + task = rpc_call_null_helper(clnt, xprt, cred, + RPC_TASK_SOFT|RPC_TASK_SOFTCONN|RPC_TASK_ASYNC, + &rpc_cb_add_xprt_call_ops, data); + put_rpccred(cred); + if (IS_ERR(task)) + return PTR_ERR(task); + rpc_put_task(task); + return 1; +} +EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); + +/** + * rpc_clnt_setup_test_and_add_xprt() + * + * This is an rpc_clnt_add_xprt setup() function which returns 1 so: + * 1) caller of the test function must dereference the rpc_xprt_switch + * and the rpc_xprt. + * 2) test function must call rpc_xprt_switch_add_xprt, usually in + * the rpc_call_done routine. + * + * Upon success (return of 1), the test function adds the new + * transport to the rpc_clnt xprt switch + * + * @clnt: struct rpc_clnt to get the new transport + * @xps: the rpc_xprt_switch to hold the new transport + * @xprt: the rpc_xprt to test + * @data: a struct rpc_add_xprt_test pointer that holds the test function + * and test function call data + */ +int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt, + struct rpc_xprt_switch *xps, + struct rpc_xprt *xprt, + void *data) +{ + struct rpc_cred *cred; + struct rpc_task *task; + struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data; + int status = -EADDRINUSE; + + xprt = xprt_get(xprt); + xprt_switch_get(xps); + + if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) + goto out_err; + + /* Test the connection */ + cred = authnull_ops.lookup_cred(NULL, NULL, 0); + task = rpc_call_null_helper(clnt, xprt, cred, + RPC_TASK_SOFT | RPC_TASK_SOFTCONN, + NULL, NULL); + put_rpccred(cred); + if (IS_ERR(task)) { + status = PTR_ERR(task); + goto out_err; + } + status = task->tk_status; + rpc_put_task(task); + + if (status < 0) + goto out_err; + + /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */ + xtest->add_xprt_test(clnt, xprt, xtest->data); + + /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */ + return 1; +out_err: + xprt_put(xprt); + xprt_switch_put(xps); + pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not added\n", + status, xprt->address_strings[RPC_DISPLAY_ADDR]); + return status; +} +EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt); + +/** + * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt + * @clnt: pointer to struct rpc_clnt + * @xprtargs: pointer to struct xprt_create + * @setup: callback to test and/or set up the connection + * @data: pointer to setup function data + * + * Creates a new transport using the parameters set in args and + * adds it to clnt. + * If ping is set, then test that connectivity succeeds before + * adding the new transport. + * + */ +int rpc_clnt_add_xprt(struct rpc_clnt *clnt, + struct xprt_create *xprtargs, + int (*setup)(struct rpc_clnt *, + struct rpc_xprt_switch *, + struct rpc_xprt *, + void *), + void *data) +{ + struct rpc_xprt_switch *xps; + struct rpc_xprt *xprt; + unsigned long connect_timeout; + unsigned long reconnect_timeout; + unsigned char resvport; + int ret = 0; + + rcu_read_lock(); + xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); + xprt = xprt_iter_xprt(&clnt->cl_xpi); + if (xps == NULL || xprt == NULL) { + rcu_read_unlock(); + xprt_switch_put(xps); + return -EAGAIN; + } + resvport = xprt->resvport; + connect_timeout = xprt->connect_timeout; + reconnect_timeout = xprt->max_reconnect_timeout; + rcu_read_unlock(); + + xprt = xprt_create_transport(xprtargs); + if (IS_ERR(xprt)) { + ret = PTR_ERR(xprt); + goto out_put_switch; + } + xprt->resvport = resvport; + if (xprt->ops->set_connect_timeout != NULL) + xprt->ops->set_connect_timeout(xprt, + connect_timeout, + reconnect_timeout); + + rpc_xprt_switch_set_roundrobin(xps); + if (setup) { + ret = setup(clnt, xps, xprt, data); + if (ret != 0) + goto out_put_xprt; + } + rpc_xprt_switch_add_xprt(xps, xprt); +out_put_xprt: + xprt_put(xprt); +out_put_switch: + xprt_switch_put(xps); + return ret; +} +EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); + +struct connect_timeout_data { + unsigned long connect_timeout; + unsigned long reconnect_timeout; +}; + +static int +rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt, + struct rpc_xprt *xprt, + void *data) +{ + struct connect_timeout_data *timeo = data; + + if (xprt->ops->set_connect_timeout) + xprt->ops->set_connect_timeout(xprt, + timeo->connect_timeout, + timeo->reconnect_timeout); + return 0; +} + +void +rpc_set_connect_timeout(struct rpc_clnt *clnt, + unsigned long connect_timeout, + unsigned long reconnect_timeout) +{ + struct connect_timeout_data timeout = { + .connect_timeout = connect_timeout, + .reconnect_timeout = reconnect_timeout, + }; + rpc_clnt_iterate_for_each_xprt(clnt, + rpc_xprt_set_connect_timeout, + &timeout); +} +EXPORT_SYMBOL_GPL(rpc_set_connect_timeout); + +void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt) +{ + rcu_read_lock(); + xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put); + +void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) +{ + rcu_read_lock(); + rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), + xprt); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt); + +bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt, + const struct sockaddr *sap) +{ + struct rpc_xprt_switch *xps; + bool ret; + + rcu_read_lock(); + xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); + ret = rpc_xprt_switch_has_addr(xps, sap); + rcu_read_unlock(); + return ret; +} +EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr); + +#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 + +#if IS_ENABLED(CONFIG_SUNRPC_SWAP) +static int +rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, + struct rpc_xprt *xprt, + void *dummy) +{ + return xprt_enable_swap(xprt); +} + +int +rpc_clnt_swap_activate(struct rpc_clnt *clnt) +{ + if (atomic_inc_return(&clnt->cl_swapper) == 1) + return rpc_clnt_iterate_for_each_xprt(clnt, + rpc_clnt_swap_activate_callback, NULL); + return 0; +} +EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); + +static int +rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, + struct rpc_xprt *xprt, + void *dummy) +{ + xprt_disable_swap(xprt); + return 0; +} + +void +rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) +{ + if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) + rpc_clnt_iterate_for_each_xprt(clnt, + rpc_clnt_swap_deactivate_callback, NULL); +} +EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); +#endif /* CONFIG_SUNRPC_SWAP */ |