11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/net/sunrpc/xprt.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * This is a generic RPC call interface supporting congestion avoidance, 51da177e4SLinus Torvalds * and asynchronous calls. 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * The interface works like this: 81da177e4SLinus Torvalds * 91da177e4SLinus Torvalds * - When a process places a call, it allocates a request slot if 101da177e4SLinus Torvalds * one is available. Otherwise, it sleeps on the backlog queue 111da177e4SLinus Torvalds * (xprt_reserve). 121da177e4SLinus Torvalds * - Next, the caller puts together the RPC message, stuffs it into 1355aa4f58SChuck Lever * the request struct, and calls xprt_transmit(). 1455aa4f58SChuck Lever * - xprt_transmit sends the message and installs the caller on the 1555ae1aabSRicardo Labiaga * transport's wait list. At the same time, if a reply is expected, 1655ae1aabSRicardo Labiaga * it installs a timer that is run after the packet's timeout has 1755ae1aabSRicardo Labiaga * expired. 181da177e4SLinus Torvalds * - When a packet arrives, the data_ready handler walks the list of 1955aa4f58SChuck Lever * pending requests for that transport. If a matching XID is found, the 201da177e4SLinus Torvalds * caller is woken up, and the timer removed. 211da177e4SLinus Torvalds * - When no reply arrives within the timeout interval, the timer is 221da177e4SLinus Torvalds * fired by the kernel and runs xprt_timer(). It either adjusts the 231da177e4SLinus Torvalds * timeout values (minor timeout) or wakes up the caller with a status 241da177e4SLinus Torvalds * of -ETIMEDOUT. 251da177e4SLinus Torvalds * - When the caller receives a notification from RPC that a reply arrived, 261da177e4SLinus Torvalds * it should release the RPC slot, and process the reply. 271da177e4SLinus Torvalds * If the call timed out, it may choose to retry the operation by 281da177e4SLinus Torvalds * adjusting the initial timeout value, and simply calling rpc_call 291da177e4SLinus Torvalds * again. 301da177e4SLinus Torvalds * 311da177e4SLinus Torvalds * Support for async RPC is done through a set of RPC-specific scheduling 321da177e4SLinus Torvalds * primitives that `transparently' work for processes as well as async 331da177e4SLinus Torvalds * tasks that rely on callbacks. 341da177e4SLinus Torvalds * 351da177e4SLinus Torvalds * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> 3655aa4f58SChuck Lever * 3755aa4f58SChuck Lever * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> 381da177e4SLinus Torvalds */ 391da177e4SLinus Torvalds 40a246b010SChuck Lever #include <linux/module.h> 41a246b010SChuck Lever 421da177e4SLinus Torvalds #include <linux/types.h> 43a246b010SChuck Lever #include <linux/interrupt.h> 441da177e4SLinus Torvalds #include <linux/workqueue.h> 45bf3fcf89SChuck Lever #include <linux/net.h> 46ff839970SChuck Lever #include <linux/ktime.h> 471da177e4SLinus Torvalds 48a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 4911c556b3SChuck Lever #include <linux/sunrpc/metrics.h> 50c9acb42eSTrond Myklebust #include <linux/sunrpc/bc_xprt.h> 511da177e4SLinus Torvalds 5255ae1aabSRicardo Labiaga #include "sunrpc.h" 5355ae1aabSRicardo Labiaga 541da177e4SLinus Torvalds /* 551da177e4SLinus Torvalds * Local variables 561da177e4SLinus Torvalds */ 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds #ifdef RPC_DEBUG 591da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 601da177e4SLinus Torvalds #endif 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds /* 631da177e4SLinus Torvalds * Local functions 641da177e4SLinus Torvalds */ 651da177e4SLinus Torvalds static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); 661da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 671da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 681da177e4SLinus Torvalds 695ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7081c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7181c098afS\"Talpey, Thomas\ 72555ee3afSChuck Lever /* 73555ee3afSChuck Lever * The transport code maintains an estimate on the maximum number of out- 74555ee3afSChuck Lever * standing RPC requests, using a smoothed version of the congestion 75555ee3afSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 76555ee3afSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 77555ee3afSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 78555ee3afSChuck Lever * 79555ee3afSChuck Lever * - a reply is received and 80555ee3afSChuck Lever * - a full number of requests are outstanding and 81555ee3afSChuck Lever * - the congestion window hasn't been updated recently. 82555ee3afSChuck Lever */ 83555ee3afSChuck Lever #define RPC_CWNDSHIFT (8U) 84555ee3afSChuck Lever #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 85555ee3afSChuck Lever #define RPC_INITCWND RPC_CWNDSCALE 86555ee3afSChuck Lever #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 87555ee3afSChuck Lever 88555ee3afSChuck Lever #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 891da177e4SLinus Torvalds 9012a80469SChuck Lever /** 9181c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 9281c098afS\"Talpey, Thomas\ * @transport: transport to register 9381c098afS\"Talpey, Thomas\ * 9481c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 9581c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 9681c098afS\"Talpey, Thomas\ * 9781c098afS\"Talpey, Thomas\ * Returns: 9881c098afS\"Talpey, Thomas\ * 0: transport successfully registered 9981c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 10081c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 10181c098afS\"Talpey, Thomas\ */ 10281c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 10381c098afS\"Talpey, Thomas\ { 10481c098afS\"Talpey, Thomas\ struct xprt_class *t; 10581c098afS\"Talpey, Thomas\ int result; 10681c098afS\"Talpey, Thomas\ 10781c098afS\"Talpey, Thomas\ result = -EEXIST; 10881c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 10981c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 11081c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 1114fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 11281c098afS\"Talpey, Thomas\ goto out; 11381c098afS\"Talpey, Thomas\ } 11481c098afS\"Talpey, Thomas\ 11581c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 11681c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 11781c098afS\"Talpey, Thomas\ transport->name); 11881c098afS\"Talpey, Thomas\ result = 0; 11981c098afS\"Talpey, Thomas\ 12081c098afS\"Talpey, Thomas\ out: 12181c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 12281c098afS\"Talpey, Thomas\ return result; 12381c098afS\"Talpey, Thomas\ } 12481c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 12581c098afS\"Talpey, Thomas\ 12681c098afS\"Talpey, Thomas\ /** 12781c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 12865b6e42cSRandy Dunlap * @transport: transport to unregister 12981c098afS\"Talpey, Thomas\ * 13081c098afS\"Talpey, Thomas\ * Returns: 13181c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 13281c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 13381c098afS\"Talpey, Thomas\ */ 13481c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 13581c098afS\"Talpey, Thomas\ { 13681c098afS\"Talpey, Thomas\ struct xprt_class *t; 13781c098afS\"Talpey, Thomas\ int result; 13881c098afS\"Talpey, Thomas\ 13981c098afS\"Talpey, Thomas\ result = 0; 14081c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 14181c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 14281c098afS\"Talpey, Thomas\ if (t == transport) { 14381c098afS\"Talpey, Thomas\ printk(KERN_INFO 14481c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 14581c098afS\"Talpey, Thomas\ transport->name); 14681c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 14781c098afS\"Talpey, Thomas\ goto out; 14881c098afS\"Talpey, Thomas\ } 14981c098afS\"Talpey, Thomas\ } 15081c098afS\"Talpey, Thomas\ result = -ENOENT; 15181c098afS\"Talpey, Thomas\ 15281c098afS\"Talpey, Thomas\ out: 15381c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 15481c098afS\"Talpey, Thomas\ return result; 15581c098afS\"Talpey, Thomas\ } 15681c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 15781c098afS\"Talpey, Thomas\ 15881c098afS\"Talpey, Thomas\ /** 159441e3e24STom Talpey * xprt_load_transport - load a transport implementation 160441e3e24STom Talpey * @transport_name: transport to load 161441e3e24STom Talpey * 162441e3e24STom Talpey * Returns: 163441e3e24STom Talpey * 0: transport successfully loaded 164441e3e24STom Talpey * -ENOENT: transport module not available 165441e3e24STom Talpey */ 166441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 167441e3e24STom Talpey { 168441e3e24STom Talpey struct xprt_class *t; 169441e3e24STom Talpey int result; 170441e3e24STom Talpey 171441e3e24STom Talpey result = 0; 172441e3e24STom Talpey spin_lock(&xprt_list_lock); 173441e3e24STom Talpey list_for_each_entry(t, &xprt_list, list) { 174441e3e24STom Talpey if (strcmp(t->name, transport_name) == 0) { 175441e3e24STom Talpey spin_unlock(&xprt_list_lock); 176441e3e24STom Talpey goto out; 177441e3e24STom Talpey } 178441e3e24STom Talpey } 179441e3e24STom Talpey spin_unlock(&xprt_list_lock); 180ef7ffe8fSAlex Riesen result = request_module("xprt%s", transport_name); 181441e3e24STom Talpey out: 182441e3e24STom Talpey return result; 183441e3e24STom Talpey } 184441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 185441e3e24STom Talpey 186441e3e24STom Talpey /** 18712a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 18812a80469SChuck Lever * @task: task that is requesting access to the transport 18912a80469SChuck Lever * 19012a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 19112a80469SChuck Lever * transport connects from colliding with writes. No congestion control 19212a80469SChuck Lever * is provided. 1931da177e4SLinus Torvalds */ 19412a80469SChuck Lever int xprt_reserve_xprt(struct rpc_task *task) 1951da177e4SLinus Torvalds { 19612a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 197343952faSRahul Iyer struct rpc_xprt *xprt = req->rq_xprt; 19812a80469SChuck Lever 19912a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 20012a80469SChuck Lever if (task == xprt->snd_task) 20112a80469SChuck Lever return 1; 20212a80469SChuck Lever goto out_sleep; 20312a80469SChuck Lever } 20412a80469SChuck Lever xprt->snd_task = task; 20512a80469SChuck Lever req->rq_bytes_sent = 0; 20612a80469SChuck Lever req->rq_ntrans++; 2074d4a76f3Sj223yang@asset.uwaterloo.ca 20812a80469SChuck Lever return 1; 20912a80469SChuck Lever 21012a80469SChuck Lever out_sleep: 21146121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", 21212a80469SChuck Lever task->tk_pid, xprt); 21312a80469SChuck Lever task->tk_timeout = 0; 21412a80469SChuck Lever task->tk_status = -EAGAIN; 215ba3c578dSj223yang@asset.uwaterloo.ca if (req->rq_ntrans) 2165d00837bSTrond Myklebust rpc_sleep_on(&xprt->resend, task, NULL); 21712a80469SChuck Lever else 2185d00837bSTrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 21912a80469SChuck Lever return 0; 22012a80469SChuck Lever } 22112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 22212a80469SChuck Lever 223632e3bdcSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 224632e3bdcSTrond Myklebust { 225632e3bdcSTrond Myklebust xprt->snd_task = NULL; 226632e3bdcSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { 227632e3bdcSTrond Myklebust smp_mb__before_clear_bit(); 228632e3bdcSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 229632e3bdcSTrond Myklebust smp_mb__after_clear_bit(); 230632e3bdcSTrond Myklebust } else 231c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 232632e3bdcSTrond Myklebust } 233632e3bdcSTrond Myklebust 23412a80469SChuck Lever /* 23512a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 23612a80469SChuck Lever * @task: task that is requesting access to the transport 23712a80469SChuck Lever * 23812a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 23912a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 24012a80469SChuck Lever * woken up and given access to the transport. 24112a80469SChuck Lever */ 24212a80469SChuck Lever int xprt_reserve_xprt_cong(struct rpc_task *task) 24312a80469SChuck Lever { 24412a80469SChuck Lever struct rpc_xprt *xprt = task->tk_xprt; 2451da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 2461da177e4SLinus Torvalds 2472226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2481da177e4SLinus Torvalds if (task == xprt->snd_task) 2491da177e4SLinus Torvalds return 1; 2501da177e4SLinus Torvalds goto out_sleep; 2511da177e4SLinus Torvalds } 25212a80469SChuck Lever if (__xprt_get_cong(xprt, task)) { 2531da177e4SLinus Torvalds xprt->snd_task = task; 2541da177e4SLinus Torvalds if (req) { 2551da177e4SLinus Torvalds req->rq_bytes_sent = 0; 2561da177e4SLinus Torvalds req->rq_ntrans++; 2571da177e4SLinus Torvalds } 2581da177e4SLinus Torvalds return 1; 2591da177e4SLinus Torvalds } 260632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2611da177e4SLinus Torvalds out_sleep: 26246121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 2631da177e4SLinus Torvalds task->tk_timeout = 0; 2641da177e4SLinus Torvalds task->tk_status = -EAGAIN; 2651da177e4SLinus Torvalds if (req && req->rq_ntrans) 2665d00837bSTrond Myklebust rpc_sleep_on(&xprt->resend, task, NULL); 2671da177e4SLinus Torvalds else 2685d00837bSTrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 2691da177e4SLinus Torvalds return 0; 2701da177e4SLinus Torvalds } 27112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2721da177e4SLinus Torvalds 27312a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2741da177e4SLinus Torvalds { 2751da177e4SLinus Torvalds int retval; 2761da177e4SLinus Torvalds 2774a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 27812a80469SChuck Lever retval = xprt->ops->reserve_xprt(task); 2794a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2801da177e4SLinus Torvalds return retval; 2811da177e4SLinus Torvalds } 2821da177e4SLinus Torvalds 28312a80469SChuck Lever static void __xprt_lock_write_next(struct rpc_xprt *xprt) 2841da177e4SLinus Torvalds { 2851da177e4SLinus Torvalds struct rpc_task *task; 28649e9a890SChuck Lever struct rpc_rqst *req; 28749e9a890SChuck Lever 28849e9a890SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 28949e9a890SChuck Lever return; 29049e9a890SChuck Lever 29149e9a890SChuck Lever task = rpc_wake_up_next(&xprt->resend); 29249e9a890SChuck Lever if (!task) { 29349e9a890SChuck Lever task = rpc_wake_up_next(&xprt->sending); 29449e9a890SChuck Lever if (!task) 29549e9a890SChuck Lever goto out_unlock; 29649e9a890SChuck Lever } 29749e9a890SChuck Lever 29849e9a890SChuck Lever req = task->tk_rqstp; 29949e9a890SChuck Lever xprt->snd_task = task; 30049e9a890SChuck Lever if (req) { 30149e9a890SChuck Lever req->rq_bytes_sent = 0; 30249e9a890SChuck Lever req->rq_ntrans++; 30349e9a890SChuck Lever } 30449e9a890SChuck Lever return; 30549e9a890SChuck Lever 30649e9a890SChuck Lever out_unlock: 307632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 30849e9a890SChuck Lever } 30949e9a890SChuck Lever 31049e9a890SChuck Lever static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 31149e9a890SChuck Lever { 31249e9a890SChuck Lever struct rpc_task *task; 3131da177e4SLinus Torvalds 3142226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 3151da177e4SLinus Torvalds return; 31649e9a890SChuck Lever if (RPCXPRT_CONGESTED(xprt)) 3171da177e4SLinus Torvalds goto out_unlock; 3181da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->resend); 3191da177e4SLinus Torvalds if (!task) { 3201da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->sending); 3211da177e4SLinus Torvalds if (!task) 3221da177e4SLinus Torvalds goto out_unlock; 3231da177e4SLinus Torvalds } 32449e9a890SChuck Lever if (__xprt_get_cong(xprt, task)) { 3251da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3261da177e4SLinus Torvalds xprt->snd_task = task; 3271da177e4SLinus Torvalds if (req) { 3281da177e4SLinus Torvalds req->rq_bytes_sent = 0; 3291da177e4SLinus Torvalds req->rq_ntrans++; 3301da177e4SLinus Torvalds } 3311da177e4SLinus Torvalds return; 3321da177e4SLinus Torvalds } 3331da177e4SLinus Torvalds out_unlock: 334632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3351da177e4SLinus Torvalds } 3361da177e4SLinus Torvalds 33749e9a890SChuck Lever /** 33849e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 33949e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 34049e9a890SChuck Lever * @task: task that is releasing access to the transport 34149e9a890SChuck Lever * 34249e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 3431da177e4SLinus Torvalds */ 34449e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3451da177e4SLinus Torvalds { 3461da177e4SLinus Torvalds if (xprt->snd_task == task) { 347632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3481da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3491da177e4SLinus Torvalds } 3501da177e4SLinus Torvalds } 35112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3521da177e4SLinus Torvalds 35349e9a890SChuck Lever /** 35449e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 35549e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 35649e9a890SChuck Lever * @task: task that is releasing access to the transport 35749e9a890SChuck Lever * 35849e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 35949e9a890SChuck Lever * transport if the transport's congestion window allows it. 36049e9a890SChuck Lever */ 36149e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 36249e9a890SChuck Lever { 36349e9a890SChuck Lever if (xprt->snd_task == task) { 364632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 36549e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 36649e9a890SChuck Lever } 36749e9a890SChuck Lever } 36812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 36949e9a890SChuck Lever 37049e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3711da177e4SLinus Torvalds { 3724a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 37349e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3744a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3751da177e4SLinus Torvalds } 3761da177e4SLinus Torvalds 3771da177e4SLinus Torvalds /* 3781da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3791da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3801da177e4SLinus Torvalds */ 3811da177e4SLinus Torvalds static int 3821da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 3831da177e4SLinus Torvalds { 3841da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds if (req->rq_cong) 3871da177e4SLinus Torvalds return 1; 38846121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 3891da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 3901da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 3911da177e4SLinus Torvalds return 0; 3921da177e4SLinus Torvalds req->rq_cong = 1; 3931da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 3941da177e4SLinus Torvalds return 1; 3951da177e4SLinus Torvalds } 3961da177e4SLinus Torvalds 3971da177e4SLinus Torvalds /* 3981da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 3991da177e4SLinus Torvalds * that has been sleeping due to congestion 4001da177e4SLinus Torvalds */ 4011da177e4SLinus Torvalds static void 4021da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4031da177e4SLinus Torvalds { 4041da177e4SLinus Torvalds if (!req->rq_cong) 4051da177e4SLinus Torvalds return; 4061da177e4SLinus Torvalds req->rq_cong = 0; 4071da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 40849e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4091da177e4SLinus Torvalds } 4101da177e4SLinus Torvalds 41146c0ee8bSChuck Lever /** 412a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 413a58dd398SChuck Lever * @task: RPC request that recently completed 414a58dd398SChuck Lever * 415a58dd398SChuck Lever * Useful for transports that require congestion control. 416a58dd398SChuck Lever */ 417a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 418a58dd398SChuck Lever { 419a58dd398SChuck Lever __xprt_put_cong(task->tk_xprt, task->tk_rqstp); 420a58dd398SChuck Lever } 42112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 422a58dd398SChuck Lever 423a58dd398SChuck Lever /** 42446c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 42546c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 42646c0ee8bSChuck Lever * @result: result code of completed RPC request 42746c0ee8bSChuck Lever * 4281da177e4SLinus Torvalds * We use a time-smoothed congestion estimator to avoid heavy oscillation. 4291da177e4SLinus Torvalds */ 43046c0ee8bSChuck Lever void xprt_adjust_cwnd(struct rpc_task *task, int result) 4311da177e4SLinus Torvalds { 43246c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 43346c0ee8bSChuck Lever struct rpc_xprt *xprt = task->tk_xprt; 43446c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4351da177e4SLinus Torvalds 4361da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4371da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4381da177e4SLinus Torvalds * the result gets rounded properly. */ 4391da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4401da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4411da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 44249e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4431da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4441da177e4SLinus Torvalds cwnd >>= 1; 4451da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4461da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4471da177e4SLinus Torvalds } 4481da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4491da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4501da177e4SLinus Torvalds xprt->cwnd = cwnd; 45146c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4521da177e4SLinus Torvalds } 45312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4541da177e4SLinus Torvalds 45544fbac22SChuck Lever /** 45644fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 45744fbac22SChuck Lever * @xprt: transport with waiting tasks 45844fbac22SChuck Lever * @status: result code to plant in each task before waking it 45944fbac22SChuck Lever * 46044fbac22SChuck Lever */ 46144fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 46244fbac22SChuck Lever { 46344fbac22SChuck Lever if (status < 0) 46444fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 46544fbac22SChuck Lever else 46644fbac22SChuck Lever rpc_wake_up(&xprt->pending); 46744fbac22SChuck Lever } 46812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 46944fbac22SChuck Lever 470c7b2cae8SChuck Lever /** 471c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 472c7b2cae8SChuck Lever * @task: task to be put to sleep 4730b80ae42SRandy Dunlap * @action: function pointer to be executed after wait 474c7b2cae8SChuck Lever */ 475b6ddf64fSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) 476c7b2cae8SChuck Lever { 477c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 478c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 479c7b2cae8SChuck Lever 480c7b2cae8SChuck Lever task->tk_timeout = req->rq_timeout; 481b6ddf64fSTrond Myklebust rpc_sleep_on(&xprt->pending, task, action); 482c7b2cae8SChuck Lever } 48312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 484c7b2cae8SChuck Lever 485c7b2cae8SChuck Lever /** 486c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 487c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 488c7b2cae8SChuck Lever * 489c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 490c7b2cae8SChuck Lever */ 491c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 492c7b2cae8SChuck Lever { 493c7b2cae8SChuck Lever if (unlikely(xprt->shutdown)) 494c7b2cae8SChuck Lever return; 495c7b2cae8SChuck Lever 496c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 497c7b2cae8SChuck Lever if (xprt->snd_task) { 49846121cf7SChuck Lever dprintk("RPC: write space: waking waiting task on " 49946121cf7SChuck Lever "xprt %p\n", xprt); 500fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); 501c7b2cae8SChuck Lever } 502c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 503c7b2cae8SChuck Lever } 50412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 505c7b2cae8SChuck Lever 506fe3aca29SChuck Lever /** 507fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 508fe3aca29SChuck Lever * @task: task whose timeout is to be set 509fe3aca29SChuck Lever * 510fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 511fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 512fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 513fe3aca29SChuck Lever */ 514fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 515fe3aca29SChuck Lever { 516fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 517fe3aca29SChuck Lever } 51812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 519fe3aca29SChuck Lever 520fe3aca29SChuck Lever /* 521fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout 522fe3aca29SChuck Lever * @task: task whose timeout is to be set 523fe3aca29SChuck Lever * 524fe3aca29SChuck Lever * Set a request's retransmit timeout using the RTT estimator. 525fe3aca29SChuck Lever */ 526fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 527fe3aca29SChuck Lever { 528fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 529ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 530ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 531fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 532ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 533fe3aca29SChuck Lever 534fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 535fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 536fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 537fe3aca29SChuck Lever task->tk_timeout = max_timeout; 538fe3aca29SChuck Lever } 53912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 540fe3aca29SChuck Lever 5411da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5421da177e4SLinus Torvalds { 543ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5441da177e4SLinus Torvalds 5451da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5461da177e4SLinus Torvalds if (to->to_exponential) 5471da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5481da177e4SLinus Torvalds else 5491da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 5501da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 5511da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 5521da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 5531da177e4SLinus Torvalds } 5541da177e4SLinus Torvalds 5559903cd1cSChuck Lever /** 5569903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 5579903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 5589903cd1cSChuck Lever * 5591da177e4SLinus Torvalds */ 5601da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 5611da177e4SLinus Torvalds { 5621da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 563ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5641da177e4SLinus Torvalds int status = 0; 5651da177e4SLinus Torvalds 5661da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 5671da177e4SLinus Torvalds if (to->to_exponential) 5681da177e4SLinus Torvalds req->rq_timeout <<= 1; 5691da177e4SLinus Torvalds else 5701da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 5711da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 5721da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 5731da177e4SLinus Torvalds req->rq_retries++; 5741da177e4SLinus Torvalds } else { 5751da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 5761da177e4SLinus Torvalds req->rq_retries = 0; 5771da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5781da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 5794a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5801da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 5814a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5821da177e4SLinus Torvalds status = -ETIMEDOUT; 5831da177e4SLinus Torvalds } 5841da177e4SLinus Torvalds 5851da177e4SLinus Torvalds if (req->rq_timeout == 0) { 5861da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 5871da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 5881da177e4SLinus Torvalds } 5891da177e4SLinus Torvalds return status; 5901da177e4SLinus Torvalds } 5911da177e4SLinus Torvalds 59265f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 5931da177e4SLinus Torvalds { 59465f27f38SDavid Howells struct rpc_xprt *xprt = 59565f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 5961da177e4SLinus Torvalds 597a246b010SChuck Lever xprt->ops->close(xprt); 59866af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 5991da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 6001da177e4SLinus Torvalds } 6011da177e4SLinus Torvalds 6029903cd1cSChuck Lever /** 60362da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6049903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6059903cd1cSChuck Lever * 6061da177e4SLinus Torvalds */ 60762da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6081da177e4SLinus Torvalds { 6091da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6104a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6111da177e4SLinus Torvalds xprt_clear_connected(xprt); 6122a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6134a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6141da177e4SLinus Torvalds } 61562da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6161da177e4SLinus Torvalds 61766af1e55STrond Myklebust /** 61866af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 61966af1e55STrond Myklebust * @xprt: transport to disconnect 62066af1e55STrond Myklebust * 62166af1e55STrond Myklebust */ 62266af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 62366af1e55STrond Myklebust { 62466af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 62566af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 62666af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 62766af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 62866af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 62966af1e55STrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6302a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 63166af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 63266af1e55STrond Myklebust } 63366af1e55STrond Myklebust 6347c1d71cfSTrond Myklebust /** 6357c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 6367c1d71cfSTrond Myklebust * @xprt: transport to disconnect 6377c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 6387c1d71cfSTrond Myklebust * 6397c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 6407c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 6417c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 6427c1d71cfSTrond Myklebust * a batch of RPC requests. 6437c1d71cfSTrond Myklebust * 6447c1d71cfSTrond Myklebust */ 6457c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 6467c1d71cfSTrond Myklebust { 6477c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 6487c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 6497c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 6507c1d71cfSTrond Myklebust goto out; 6517c1d71cfSTrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) 6527c1d71cfSTrond Myklebust goto out; 6537c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 6547c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 6557c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 6567c1d71cfSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6572a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6587c1d71cfSTrond Myklebust out: 6597c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 6607c1d71cfSTrond Myklebust } 6617c1d71cfSTrond Myklebust 6621da177e4SLinus Torvalds static void 6631da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 6641da177e4SLinus Torvalds { 6651da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 6661da177e4SLinus Torvalds 6674a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 6681da177e4SLinus Torvalds if (!list_empty(&xprt->recv) || xprt->shutdown) 6691da177e4SLinus Torvalds goto out_abort; 6702226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 6711da177e4SLinus Torvalds goto out_abort; 6724a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 673f75e6745STrond Myklebust set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); 674c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6751da177e4SLinus Torvalds return; 6761da177e4SLinus Torvalds out_abort: 6774a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 6781da177e4SLinus Torvalds } 6791da177e4SLinus Torvalds 6809903cd1cSChuck Lever /** 6819903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 6829903cd1cSChuck Lever * @task: RPC task that is requesting the connect 6831da177e4SLinus Torvalds * 6841da177e4SLinus Torvalds */ 6851da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 6861da177e4SLinus Torvalds { 6871da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6881da177e4SLinus Torvalds 68946121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 6901da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 6911da177e4SLinus Torvalds 692ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 69301d37c42STrond Myklebust task->tk_status = -EAGAIN; 6941da177e4SLinus Torvalds return; 6951da177e4SLinus Torvalds } 6961da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 6971da177e4SLinus Torvalds return; 698feb8ca37STrond Myklebust 699feb8ca37STrond Myklebust if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) 700feb8ca37STrond Myklebust xprt->ops->close(xprt); 701feb8ca37STrond Myklebust 7021da177e4SLinus Torvalds if (xprt_connected(xprt)) 703a246b010SChuck Lever xprt_release_write(xprt, task); 704a246b010SChuck Lever else { 7051da177e4SLinus Torvalds if (task->tk_rqstp) 7061da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 7071da177e4SLinus Torvalds 708a8ce4a8fSTrond Myklebust task->tk_timeout = task->tk_rqstp->rq_timeout; 7095d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_connect_status); 7100b9e7943STrond Myklebust 7110b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 7120b9e7943STrond Myklebust return; 7130b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 7140b9e7943STrond Myklebust return; 715262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 716a246b010SChuck Lever xprt->ops->connect(task); 7171da177e4SLinus Torvalds } 7181da177e4SLinus Torvalds } 7191da177e4SLinus Torvalds 7209903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 7211da177e4SLinus Torvalds { 7221da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 7231da177e4SLinus Torvalds 724cd983ef8SChuck Lever if (task->tk_status == 0) { 725262ca07dSChuck Lever xprt->stat.connect_count++; 726262ca07dSChuck Lever xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; 72746121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connection established\n", 7281da177e4SLinus Torvalds task->tk_pid); 7291da177e4SLinus Torvalds return; 7301da177e4SLinus Torvalds } 7311da177e4SLinus Torvalds 7321da177e4SLinus Torvalds switch (task->tk_status) { 7332a491991STrond Myklebust case -EAGAIN: 7342a491991STrond Myklebust dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); 73523475d66SChuck Lever break; 7361da177e4SLinus Torvalds case -ETIMEDOUT: 73746121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connect attempt timed " 73846121cf7SChuck Lever "out\n", task->tk_pid); 7391da177e4SLinus Torvalds break; 7401da177e4SLinus Torvalds default: 74146121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: error %d connecting to " 74246121cf7SChuck Lever "server %s\n", task->tk_pid, -task->tk_status, 74346121cf7SChuck Lever task->tk_client->cl_server); 7441da177e4SLinus Torvalds xprt_release_write(xprt, task); 74523475d66SChuck Lever task->tk_status = -EIO; 74623475d66SChuck Lever } 7471da177e4SLinus Torvalds } 7481da177e4SLinus Torvalds 7499903cd1cSChuck Lever /** 7509903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 7519903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 7529903cd1cSChuck Lever * @xid: RPC XID of incoming reply 7539903cd1cSChuck Lever * 7541da177e4SLinus Torvalds */ 755d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 7561da177e4SLinus Torvalds { 7578f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 7581da177e4SLinus Torvalds 7598f3a6de3SPavel Emelyanov list_for_each_entry(entry, &xprt->recv, rq_list) 760262ca07dSChuck Lever if (entry->rq_xid == xid) 761262ca07dSChuck Lever return entry; 76246121cf7SChuck Lever 76346121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 76446121cf7SChuck Lever ntohl(xid)); 765262ca07dSChuck Lever xprt->stat.bad_xids++; 766262ca07dSChuck Lever return NULL; 7671da177e4SLinus Torvalds } 76812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 7691da177e4SLinus Torvalds 770bbc72ceaSChuck Lever static void xprt_update_rtt(struct rpc_task *task) 7711da177e4SLinus Torvalds { 7721570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 7731570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 7741da177e4SLinus Torvalds unsigned timer = task->tk_msg.rpc_proc->p_timer; 775d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 7761570c1e4SChuck Lever 7771da177e4SLinus Torvalds if (timer) { 7781da177e4SLinus Torvalds if (req->rq_ntrans == 1) 779ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 7801570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 7811da177e4SLinus Torvalds } 7821da177e4SLinus Torvalds } 7831da177e4SLinus Torvalds 7841570c1e4SChuck Lever /** 7851570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 7861570c1e4SChuck Lever * @task: RPC request that recently completed 7871570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 7881570c1e4SChuck Lever * 7891570c1e4SChuck Lever * Caller holds transport lock. 7901570c1e4SChuck Lever */ 7911570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 7921570c1e4SChuck Lever { 7931570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 794fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 7951da177e4SLinus Torvalds 7961570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 7971570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 7981da177e4SLinus Torvalds 799fda13939STrond Myklebust xprt->stat.recvs++; 800d60dbb20STrond Myklebust req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); 801bbc72ceaSChuck Lever if (xprt->ops->timer != NULL) 802bbc72ceaSChuck Lever xprt_update_rtt(task); 803ef759a2eSChuck Lever 8041da177e4SLinus Torvalds list_del_init(&req->rq_list); 8051e799b67STrond Myklebust req->rq_private_buf.len = copied; 806dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 807dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 80843ac3f29STrond Myklebust smp_wmb(); 809dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 810fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 8111da177e4SLinus Torvalds } 81212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 8131da177e4SLinus Torvalds 81446c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 8151da177e4SLinus Torvalds { 8161da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8171da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8181da177e4SLinus Torvalds 8195d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 8205d00837bSTrond Myklebust return; 82146121cf7SChuck Lever dprintk("RPC: %5u xprt_timer\n", task->tk_pid); 82246c0ee8bSChuck Lever 8235d00837bSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 824dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 82546c0ee8bSChuck Lever if (xprt->ops->timer) 82646c0ee8bSChuck Lever xprt->ops->timer(task); 8275d00837bSTrond Myklebust } else 8285d00837bSTrond Myklebust task->tk_status = 0; 8295d00837bSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 8301da177e4SLinus Torvalds } 8311da177e4SLinus Torvalds 8324cfc7e60SRahul Iyer static inline int xprt_has_timer(struct rpc_xprt *xprt) 8334cfc7e60SRahul Iyer { 8344cfc7e60SRahul Iyer return xprt->idle_timeout != 0; 8354cfc7e60SRahul Iyer } 8364cfc7e60SRahul Iyer 8379903cd1cSChuck Lever /** 8389903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 8399903cd1cSChuck Lever * @task: RPC task about to send a request 8409903cd1cSChuck Lever * 8411da177e4SLinus Torvalds */ 8429903cd1cSChuck Lever int xprt_prepare_transmit(struct rpc_task *task) 8431da177e4SLinus Torvalds { 8441da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8451da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8461da177e4SLinus Torvalds int err = 0; 8471da177e4SLinus Torvalds 84846121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 8491da177e4SLinus Torvalds 8504a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 851dd2b63d0SRicardo Labiaga if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) { 852dd2b63d0SRicardo Labiaga err = req->rq_reply_bytes_recvd; 8531da177e4SLinus Torvalds goto out_unlock; 8541da177e4SLinus Torvalds } 8552a491991STrond Myklebust if (!xprt->ops->reserve_xprt(task)) 8561da177e4SLinus Torvalds err = -EAGAIN; 8571da177e4SLinus Torvalds out_unlock: 8584a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 8591da177e4SLinus Torvalds return err; 8601da177e4SLinus Torvalds } 8611da177e4SLinus Torvalds 862e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 8635e5ce5beSTrond Myklebust { 864343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 8655e5ce5beSTrond Myklebust } 8665e5ce5beSTrond Myklebust 8679903cd1cSChuck Lever /** 8689903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 8699903cd1cSChuck Lever * @task: controlling RPC task 8709903cd1cSChuck Lever * 8719903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 8729903cd1cSChuck Lever */ 8739903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 8741da177e4SLinus Torvalds { 8751da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8761da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 877a246b010SChuck Lever int status; 8781da177e4SLinus Torvalds 87946121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 8801da177e4SLinus Torvalds 881dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 88255ae1aabSRicardo Labiaga if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { 88355ae1aabSRicardo Labiaga /* 88455ae1aabSRicardo Labiaga * Add to the list only if we're expecting a reply 88555ae1aabSRicardo Labiaga */ 8864a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 8871da177e4SLinus Torvalds /* Update the softirq receive buffer */ 8881da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 8891da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 8901da177e4SLinus Torvalds /* Add request to the receive list */ 8911da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 8924a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 8931da177e4SLinus Torvalds xprt_reset_majortimeo(req); 8940f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 8950f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 8961da177e4SLinus Torvalds } 8971da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 8981da177e4SLinus Torvalds return; 8991da177e4SLinus Torvalds 9007c1d71cfSTrond Myklebust req->rq_connect_cookie = xprt->connect_cookie; 901ff839970SChuck Lever req->rq_xtime = ktime_get(); 902a246b010SChuck Lever status = xprt->ops->send_request(task); 903c8485e4dSTrond Myklebust if (status != 0) { 904c8485e4dSTrond Myklebust task->tk_status = status; 905c8485e4dSTrond Myklebust return; 906c8485e4dSTrond Myklebust } 907c8485e4dSTrond Myklebust 90846121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 909468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 910fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 911262ca07dSChuck Lever 912fe3aca29SChuck Lever xprt->ops->set_retrans_timeout(task); 913262ca07dSChuck Lever 914262ca07dSChuck Lever xprt->stat.sends++; 915262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 916262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 917262ca07dSChuck Lever 918fe3aca29SChuck Lever /* Don't race with disconnect */ 919fe3aca29SChuck Lever if (!xprt_connected(xprt)) 920fe3aca29SChuck Lever task->tk_status = -ENOTCONN; 921dd2b63d0SRicardo Labiaga else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) { 92255ae1aabSRicardo Labiaga /* 92355ae1aabSRicardo Labiaga * Sleep on the pending queue since 92455ae1aabSRicardo Labiaga * we're expecting a reply. 92555ae1aabSRicardo Labiaga */ 9265d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 92755ae1aabSRicardo Labiaga } 928fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9291da177e4SLinus Torvalds } 9301da177e4SLinus Torvalds 931ee5ebe85STrond Myklebust static void xprt_alloc_slot(struct rpc_task *task) 9321da177e4SLinus Torvalds { 9331da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 9341da177e4SLinus Torvalds 9351da177e4SLinus Torvalds task->tk_status = 0; 9361da177e4SLinus Torvalds if (task->tk_rqstp) 9371da177e4SLinus Torvalds return; 9381da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 9391da177e4SLinus Torvalds struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 9401da177e4SLinus Torvalds list_del_init(&req->rq_list); 9411da177e4SLinus Torvalds task->tk_rqstp = req; 9421da177e4SLinus Torvalds xprt_request_init(task, xprt); 9431da177e4SLinus Torvalds return; 9441da177e4SLinus Torvalds } 9451da177e4SLinus Torvalds dprintk("RPC: waiting for request slot\n"); 9461da177e4SLinus Torvalds task->tk_status = -EAGAIN; 9471da177e4SLinus Torvalds task->tk_timeout = 0; 9485d00837bSTrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 9491da177e4SLinus Torvalds } 9501da177e4SLinus Torvalds 951ee5ebe85STrond Myklebust static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 952ee5ebe85STrond Myklebust { 953ee5ebe85STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 954ee5ebe85STrond Myklebust 955ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 956ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 957ee5ebe85STrond Myklebust rpc_wake_up_next(&xprt->backlog); 958ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 959ee5ebe85STrond Myklebust } 960ee5ebe85STrond Myklebust 96137aa2133SPavel Emelyanov struct rpc_xprt *xprt_alloc(struct net *net, int size, int max_req) 962bd1722d4SPavel Emelyanov { 963bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 964bd1722d4SPavel Emelyanov 965bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 966bd1722d4SPavel Emelyanov if (xprt == NULL) 967bd1722d4SPavel Emelyanov goto out; 968a8de240aSTrond Myklebust atomic_set(&xprt->count, 1); 969bd1722d4SPavel Emelyanov 970bd1722d4SPavel Emelyanov xprt->max_reqs = max_req; 971bd1722d4SPavel Emelyanov xprt->slot = kcalloc(max_req, sizeof(struct rpc_rqst), GFP_KERNEL); 972bd1722d4SPavel Emelyanov if (xprt->slot == NULL) 973bd1722d4SPavel Emelyanov goto out_free; 974bd1722d4SPavel Emelyanov 97537aa2133SPavel Emelyanov xprt->xprt_net = get_net(net); 976bd1722d4SPavel Emelyanov return xprt; 977bd1722d4SPavel Emelyanov 978bd1722d4SPavel Emelyanov out_free: 979bd1722d4SPavel Emelyanov kfree(xprt); 980bd1722d4SPavel Emelyanov out: 981bd1722d4SPavel Emelyanov return NULL; 982bd1722d4SPavel Emelyanov } 983bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 984bd1722d4SPavel Emelyanov 985e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 986e204e621SPavel Emelyanov { 98737aa2133SPavel Emelyanov put_net(xprt->xprt_net); 988e204e621SPavel Emelyanov kfree(xprt->slot); 989e204e621SPavel Emelyanov kfree(xprt); 990e204e621SPavel Emelyanov } 991e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 992e204e621SPavel Emelyanov 9939903cd1cSChuck Lever /** 9949903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 9959903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 9969903cd1cSChuck Lever * 9979903cd1cSChuck Lever * If no more slots are available, place the task on the transport's 9989903cd1cSChuck Lever * backlog queue. 9999903cd1cSChuck Lever */ 10009903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 10011da177e4SLinus Torvalds { 10021da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 10031da177e4SLinus Torvalds 10041da177e4SLinus Torvalds task->tk_status = -EIO; 10055dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 1006ee5ebe85STrond Myklebust xprt_alloc_slot(task); 10075dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 10081da177e4SLinus Torvalds } 10091da177e4SLinus Torvalds 1010d8ed029dSAlexey Dobriyan static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) 10111da177e4SLinus Torvalds { 10120eae88f3SEric Dumazet return (__force __be32)xprt->xid++; 10131da177e4SLinus Torvalds } 10141da177e4SLinus Torvalds 10151da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 10161da177e4SLinus Torvalds { 1017bf3fcf89SChuck Lever xprt->xid = net_random(); 10181da177e4SLinus Torvalds } 10191da177e4SLinus Torvalds 10209903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 10211da177e4SLinus Torvalds { 10221da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 10231da177e4SLinus Torvalds 1024ba7392bbSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 10251da177e4SLinus Torvalds req->rq_task = task; 10261da177e4SLinus Torvalds req->rq_xprt = xprt; 102702107148SChuck Lever req->rq_buffer = NULL; 10281da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 1029ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf = NULL; 1030da45828eSTrond Myklebust xprt_reset_majortimeo(req); 103146121cf7SChuck Lever dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 10321da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 10331da177e4SLinus Torvalds } 10341da177e4SLinus Torvalds 10359903cd1cSChuck Lever /** 10369903cd1cSChuck Lever * xprt_release - release an RPC request slot 10379903cd1cSChuck Lever * @task: task which is finished with the slot 10389903cd1cSChuck Lever * 10391da177e4SLinus Torvalds */ 10409903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 10411da177e4SLinus Torvalds { 104255ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 10431da177e4SLinus Torvalds struct rpc_rqst *req; 10441da177e4SLinus Torvalds 10451da177e4SLinus Torvalds if (!(req = task->tk_rqstp)) 10461da177e4SLinus Torvalds return; 104755ae1aabSRicardo Labiaga 104855ae1aabSRicardo Labiaga xprt = req->rq_xprt; 104911c556b3SChuck Lever rpc_count_iostats(task); 10504a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 105149e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1052a58dd398SChuck Lever if (xprt->ops->release_request) 1053a58dd398SChuck Lever xprt->ops->release_request(task); 10541da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 10551da177e4SLinus Torvalds list_del(&req->rq_list); 10561da177e4SLinus Torvalds xprt->last_used = jiffies; 10574cfc7e60SRahul Iyer if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) 1058a246b010SChuck Lever mod_timer(&xprt->timer, 105903bf4b70SChuck Lever xprt->last_used + xprt->idle_timeout); 10604a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1061ee5ebe85STrond Myklebust if (req->rq_buffer) 1062c5a4dd8bSChuck Lever xprt->ops->buf_free(req->rq_buffer); 1063a17c2153STrond Myklebust if (req->rq_cred != NULL) 1064a17c2153STrond Myklebust put_rpccred(req->rq_cred); 10651da177e4SLinus Torvalds task->tk_rqstp = NULL; 1066ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1067ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 106855ae1aabSRicardo Labiaga 106946121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 1070ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1071ee5ebe85STrond Myklebust xprt_free_slot(xprt, req); 1072ee5ebe85STrond Myklebust else 1073c9acb42eSTrond Myklebust xprt_free_bc_request(req); 10741da177e4SLinus Torvalds } 10751da177e4SLinus Torvalds 10769903cd1cSChuck Lever /** 1077c2866763SChuck Lever * xprt_create_transport - create an RPC transport 107896802a09SFrank van Maarseveen * @args: rpc transport creation arguments 1079c2866763SChuck Lever * 1080c2866763SChuck Lever */ 10813c341b0bS\"Talpey, Thomas\ struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 1082c2866763SChuck Lever { 1083c2866763SChuck Lever struct rpc_xprt *xprt; 1084c2866763SChuck Lever struct rpc_rqst *req; 1085bc25571eS\"Talpey, Thomas\ struct xprt_class *t; 1086c2866763SChuck Lever 1087bc25571eS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 1088bc25571eS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 10894fa016ebS\"Talpey, Thomas\ if (t->ident == args->ident) { 1090bc25571eS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 1091bc25571eS\"Talpey, Thomas\ goto found; 1092c2866763SChuck Lever } 1093bc25571eS\"Talpey, Thomas\ } 1094bc25571eS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 10954fa016ebS\"Talpey, Thomas\ printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); 1096bc25571eS\"Talpey, Thomas\ return ERR_PTR(-EIO); 1097bc25571eS\"Talpey, Thomas\ 1098bc25571eS\"Talpey, Thomas\ found: 1099bc25571eS\"Talpey, Thomas\ xprt = t->setup(args); 1100c8541ecdSChuck Lever if (IS_ERR(xprt)) { 1101c8541ecdSChuck Lever dprintk("RPC: xprt_create_transport: failed, %ld\n", 1102c8541ecdSChuck Lever -PTR_ERR(xprt)); 1103c8541ecdSChuck Lever return xprt; 1104c2866763SChuck Lever } 1105f0418aa4SJ. Bruce Fields if (test_and_set_bit(XPRT_INITIALIZED, &xprt->state)) 1106f0418aa4SJ. Bruce Fields /* ->setup returned a pre-initialized xprt: */ 1107f0418aa4SJ. Bruce Fields return xprt; 1108c2866763SChuck Lever 1109c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1110c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 1111c2866763SChuck Lever 1112c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 1113c2866763SChuck Lever INIT_LIST_HEAD(&xprt->recv); 11149e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1115f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1116f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 11179e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1118f9acac1aSRicardo Labiaga 111965f27f38SDavid Howells INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 11204cfc7e60SRahul Iyer if (xprt_has_timer(xprt)) 1121b24b8a24SPavel Emelyanov setup_timer(&xprt->timer, xprt_init_autodisconnect, 1122b24b8a24SPavel Emelyanov (unsigned long)xprt); 11234cfc7e60SRahul Iyer else 11244cfc7e60SRahul Iyer init_timer(&xprt->timer); 1125c2866763SChuck Lever xprt->last_used = jiffies; 1126c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1127a509050bSChuck Lever xprt->bind_index = 0; 1128c2866763SChuck Lever 1129c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1130c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 1131c2866763SChuck Lever rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 1132c2866763SChuck Lever rpc_init_wait_queue(&xprt->resend, "xprt_resend"); 1133c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1134c2866763SChuck Lever 1135c2866763SChuck Lever /* initialize free list */ 1136c2866763SChuck Lever for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) 1137c2866763SChuck Lever list_add(&req->rq_list, &xprt->free); 1138c2866763SChuck Lever 1139c2866763SChuck Lever xprt_init_xid(xprt); 1140c2866763SChuck Lever 1141c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1142c2866763SChuck Lever xprt->max_reqs); 1143c2866763SChuck Lever return xprt; 1144c2866763SChuck Lever } 1145c2866763SChuck Lever 11469903cd1cSChuck Lever /** 11479903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 1148a8de240aSTrond Myklebust * @xprt: transport to destroy 11499903cd1cSChuck Lever * 11501da177e4SLinus Torvalds */ 1151a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 11521da177e4SLinus Torvalds { 11531da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 11540065db32STrond Myklebust xprt->shutdown = 1; 11550065db32STrond Myklebust del_timer_sync(&xprt->timer); 1156c8541ecdSChuck Lever 1157f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1158f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1159f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1160f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->resend); 1161f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1162c3ae62aeSJ. Bruce Fields cancel_work_sync(&xprt->task_cleanup); 1163c8541ecdSChuck Lever /* 1164c8541ecdSChuck Lever * Tear down transport state and free the rpc_xprt 1165c8541ecdSChuck Lever */ 1166a246b010SChuck Lever xprt->ops->destroy(xprt); 11676b6ca86bSTrond Myklebust } 11681da177e4SLinus Torvalds 11696b6ca86bSTrond Myklebust /** 11706b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 11716b6ca86bSTrond Myklebust * @xprt: pointer to the transport 11726b6ca86bSTrond Myklebust * 11736b6ca86bSTrond Myklebust */ 11746b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 11756b6ca86bSTrond Myklebust { 1176a8de240aSTrond Myklebust if (atomic_dec_and_test(&xprt->count)) 1177a8de240aSTrond Myklebust xprt_destroy(xprt); 11786b6ca86bSTrond Myklebust } 11796b6ca86bSTrond Myklebust 11806b6ca86bSTrond Myklebust /** 11816b6ca86bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 11826b6ca86bSTrond Myklebust * @xprt: pointer to the transport 11836b6ca86bSTrond Myklebust * 11846b6ca86bSTrond Myklebust */ 11856b6ca86bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 11866b6ca86bSTrond Myklebust { 1187a8de240aSTrond Myklebust if (atomic_inc_not_zero(&xprt->count)) 11886b6ca86bSTrond Myklebust return xprt; 1189a8de240aSTrond Myklebust return NULL; 11901da177e4SLinus Torvalds } 1191