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 1555aa4f58SChuck Lever * transport's wait list. At the same time, it installs a timer that 161da177e4SLinus Torvalds * is run after the packet's timeout has expired. 171da177e4SLinus Torvalds * - When a packet arrives, the data_ready handler walks the list of 1855aa4f58SChuck Lever * pending requests for that transport. If a matching XID is found, the 191da177e4SLinus Torvalds * caller is woken up, and the timer removed. 201da177e4SLinus Torvalds * - When no reply arrives within the timeout interval, the timer is 211da177e4SLinus Torvalds * fired by the kernel and runs xprt_timer(). It either adjusts the 221da177e4SLinus Torvalds * timeout values (minor timeout) or wakes up the caller with a status 231da177e4SLinus Torvalds * of -ETIMEDOUT. 241da177e4SLinus Torvalds * - When the caller receives a notification from RPC that a reply arrived, 251da177e4SLinus Torvalds * it should release the RPC slot, and process the reply. 261da177e4SLinus Torvalds * If the call timed out, it may choose to retry the operation by 271da177e4SLinus Torvalds * adjusting the initial timeout value, and simply calling rpc_call 281da177e4SLinus Torvalds * again. 291da177e4SLinus Torvalds * 301da177e4SLinus Torvalds * Support for async RPC is done through a set of RPC-specific scheduling 311da177e4SLinus Torvalds * primitives that `transparently' work for processes as well as async 321da177e4SLinus Torvalds * tasks that rely on callbacks. 331da177e4SLinus Torvalds * 341da177e4SLinus Torvalds * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> 3555aa4f58SChuck Lever * 3655aa4f58SChuck Lever * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> 371da177e4SLinus Torvalds */ 381da177e4SLinus Torvalds 39a246b010SChuck Lever #include <linux/module.h> 40a246b010SChuck Lever 411da177e4SLinus Torvalds #include <linux/types.h> 42a246b010SChuck Lever #include <linux/interrupt.h> 431da177e4SLinus Torvalds #include <linux/workqueue.h> 441da177e4SLinus Torvalds #include <linux/random.h> 451da177e4SLinus Torvalds 46a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 471da177e4SLinus Torvalds 481da177e4SLinus Torvalds /* 491da177e4SLinus Torvalds * Local variables 501da177e4SLinus Torvalds */ 511da177e4SLinus Torvalds 521da177e4SLinus Torvalds #ifdef RPC_DEBUG 531da177e4SLinus Torvalds # undef RPC_DEBUG_DATA 541da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 551da177e4SLinus Torvalds #endif 561da177e4SLinus Torvalds 571da177e4SLinus Torvalds /* 581da177e4SLinus Torvalds * Local functions 591da177e4SLinus Torvalds */ 601da177e4SLinus Torvalds static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); 611da177e4SLinus Torvalds static inline void do_xprt_reserve(struct rpc_task *); 621da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 631da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 641da177e4SLinus Torvalds 651da177e4SLinus Torvalds static int xprt_clear_backlog(struct rpc_xprt *xprt); 661da177e4SLinus Torvalds 671da177e4SLinus Torvalds /* 6855aa4f58SChuck Lever * Serialize write access to transports, in order to prevent different 691da177e4SLinus Torvalds * requests from interfering with each other. 7055aa4f58SChuck Lever * Also prevents transport connects from colliding with writes. 711da177e4SLinus Torvalds */ 721da177e4SLinus Torvalds static int 731da177e4SLinus Torvalds __xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 741da177e4SLinus Torvalds { 751da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 761da177e4SLinus Torvalds 772226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 781da177e4SLinus Torvalds if (task == xprt->snd_task) 791da177e4SLinus Torvalds return 1; 801da177e4SLinus Torvalds goto out_sleep; 811da177e4SLinus Torvalds } 821da177e4SLinus Torvalds if (xprt->nocong || __xprt_get_cong(xprt, task)) { 831da177e4SLinus Torvalds xprt->snd_task = task; 841da177e4SLinus Torvalds if (req) { 851da177e4SLinus Torvalds req->rq_bytes_sent = 0; 861da177e4SLinus Torvalds req->rq_ntrans++; 871da177e4SLinus Torvalds } 881da177e4SLinus Torvalds return 1; 891da177e4SLinus Torvalds } 901da177e4SLinus Torvalds smp_mb__before_clear_bit(); 912226feb6SChuck Lever clear_bit(XPRT_LOCKED, &xprt->state); 921da177e4SLinus Torvalds smp_mb__after_clear_bit(); 931da177e4SLinus Torvalds out_sleep: 9455aa4f58SChuck Lever dprintk("RPC: %4d failed to lock transport %p\n", task->tk_pid, xprt); 951da177e4SLinus Torvalds task->tk_timeout = 0; 961da177e4SLinus Torvalds task->tk_status = -EAGAIN; 971da177e4SLinus Torvalds if (req && req->rq_ntrans) 981da177e4SLinus Torvalds rpc_sleep_on(&xprt->resend, task, NULL, NULL); 991da177e4SLinus Torvalds else 1001da177e4SLinus Torvalds rpc_sleep_on(&xprt->sending, task, NULL, NULL); 1011da177e4SLinus Torvalds return 0; 1021da177e4SLinus Torvalds } 1031da177e4SLinus Torvalds 1041da177e4SLinus Torvalds static inline int 1051da177e4SLinus Torvalds xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 1061da177e4SLinus Torvalds { 1071da177e4SLinus Torvalds int retval; 1081da177e4SLinus Torvalds 1094a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 1101da177e4SLinus Torvalds retval = __xprt_lock_write(xprt, task); 1114a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1121da177e4SLinus Torvalds return retval; 1131da177e4SLinus Torvalds } 1141da177e4SLinus Torvalds 1151da177e4SLinus Torvalds 1161da177e4SLinus Torvalds static void 1171da177e4SLinus Torvalds __xprt_lock_write_next(struct rpc_xprt *xprt) 1181da177e4SLinus Torvalds { 1191da177e4SLinus Torvalds struct rpc_task *task; 1201da177e4SLinus Torvalds 1212226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 1221da177e4SLinus Torvalds return; 1231da177e4SLinus Torvalds if (!xprt->nocong && RPCXPRT_CONGESTED(xprt)) 1241da177e4SLinus Torvalds goto out_unlock; 1251da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->resend); 1261da177e4SLinus Torvalds if (!task) { 1271da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->sending); 1281da177e4SLinus Torvalds if (!task) 1291da177e4SLinus Torvalds goto out_unlock; 1301da177e4SLinus Torvalds } 1311da177e4SLinus Torvalds if (xprt->nocong || __xprt_get_cong(xprt, task)) { 1321da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 1331da177e4SLinus Torvalds xprt->snd_task = task; 1341da177e4SLinus Torvalds if (req) { 1351da177e4SLinus Torvalds req->rq_bytes_sent = 0; 1361da177e4SLinus Torvalds req->rq_ntrans++; 1371da177e4SLinus Torvalds } 1381da177e4SLinus Torvalds return; 1391da177e4SLinus Torvalds } 1401da177e4SLinus Torvalds out_unlock: 1411da177e4SLinus Torvalds smp_mb__before_clear_bit(); 1422226feb6SChuck Lever clear_bit(XPRT_LOCKED, &xprt->state); 1431da177e4SLinus Torvalds smp_mb__after_clear_bit(); 1441da177e4SLinus Torvalds } 1451da177e4SLinus Torvalds 1461da177e4SLinus Torvalds /* 14755aa4f58SChuck Lever * Releases the transport for use by other requests. 1481da177e4SLinus Torvalds */ 1491da177e4SLinus Torvalds static void 1501da177e4SLinus Torvalds __xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 1511da177e4SLinus Torvalds { 1521da177e4SLinus Torvalds if (xprt->snd_task == task) { 1531da177e4SLinus Torvalds xprt->snd_task = NULL; 1541da177e4SLinus Torvalds smp_mb__before_clear_bit(); 1552226feb6SChuck Lever clear_bit(XPRT_LOCKED, &xprt->state); 1561da177e4SLinus Torvalds smp_mb__after_clear_bit(); 1571da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 1581da177e4SLinus Torvalds } 1591da177e4SLinus Torvalds } 1601da177e4SLinus Torvalds 1611da177e4SLinus Torvalds static inline void 1621da177e4SLinus Torvalds xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 1631da177e4SLinus Torvalds { 1644a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 1651da177e4SLinus Torvalds __xprt_release_write(xprt, task); 1664a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1671da177e4SLinus Torvalds } 1681da177e4SLinus Torvalds 1691da177e4SLinus Torvalds /* 1701da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 1711da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 1721da177e4SLinus Torvalds */ 1731da177e4SLinus Torvalds static int 1741da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 1751da177e4SLinus Torvalds { 1761da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 1771da177e4SLinus Torvalds 1781da177e4SLinus Torvalds if (req->rq_cong) 1791da177e4SLinus Torvalds return 1; 1801da177e4SLinus Torvalds dprintk("RPC: %4d xprt_cwnd_limited cong = %ld cwnd = %ld\n", 1811da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 1821da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 1831da177e4SLinus Torvalds return 0; 1841da177e4SLinus Torvalds req->rq_cong = 1; 1851da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 1861da177e4SLinus Torvalds return 1; 1871da177e4SLinus Torvalds } 1881da177e4SLinus Torvalds 1891da177e4SLinus Torvalds /* 1901da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 1911da177e4SLinus Torvalds * that has been sleeping due to congestion 1921da177e4SLinus Torvalds */ 1931da177e4SLinus Torvalds static void 1941da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 1951da177e4SLinus Torvalds { 1961da177e4SLinus Torvalds if (!req->rq_cong) 1971da177e4SLinus Torvalds return; 1981da177e4SLinus Torvalds req->rq_cong = 0; 1991da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 2001da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 2011da177e4SLinus Torvalds } 2021da177e4SLinus Torvalds 2031da177e4SLinus Torvalds /* 2041da177e4SLinus Torvalds * Adjust RPC congestion window 2051da177e4SLinus Torvalds * We use a time-smoothed congestion estimator to avoid heavy oscillation. 2061da177e4SLinus Torvalds */ 2071da177e4SLinus Torvalds static void 2081da177e4SLinus Torvalds xprt_adjust_cwnd(struct rpc_xprt *xprt, int result) 2091da177e4SLinus Torvalds { 2101da177e4SLinus Torvalds unsigned long cwnd; 2111da177e4SLinus Torvalds 2121da177e4SLinus Torvalds cwnd = xprt->cwnd; 2131da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 2141da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 2151da177e4SLinus Torvalds * the result gets rounded properly. */ 2161da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 2171da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 2181da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 2191da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 2201da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 2211da177e4SLinus Torvalds cwnd >>= 1; 2221da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 2231da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 2241da177e4SLinus Torvalds } 2251da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 2261da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 2271da177e4SLinus Torvalds xprt->cwnd = cwnd; 2281da177e4SLinus Torvalds } 2291da177e4SLinus Torvalds 23044fbac22SChuck Lever /** 23144fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 23244fbac22SChuck Lever * @xprt: transport with waiting tasks 23344fbac22SChuck Lever * @status: result code to plant in each task before waking it 23444fbac22SChuck Lever * 23544fbac22SChuck Lever */ 23644fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 23744fbac22SChuck Lever { 23844fbac22SChuck Lever if (status < 0) 23944fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 24044fbac22SChuck Lever else 24144fbac22SChuck Lever rpc_wake_up(&xprt->pending); 24244fbac22SChuck Lever } 24344fbac22SChuck Lever 2441da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 2451da177e4SLinus Torvalds { 2461da177e4SLinus Torvalds struct rpc_timeout *to = &req->rq_xprt->timeout; 2471da177e4SLinus Torvalds 2481da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 2491da177e4SLinus Torvalds if (to->to_exponential) 2501da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 2511da177e4SLinus Torvalds else 2521da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 2531da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 2541da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 2551da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 2561da177e4SLinus Torvalds } 2571da177e4SLinus Torvalds 2589903cd1cSChuck Lever /** 2599903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 2609903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 2619903cd1cSChuck Lever * 2621da177e4SLinus Torvalds */ 2631da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 2641da177e4SLinus Torvalds { 2651da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 2661da177e4SLinus Torvalds struct rpc_timeout *to = &xprt->timeout; 2671da177e4SLinus Torvalds int status = 0; 2681da177e4SLinus Torvalds 2691da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 2701da177e4SLinus Torvalds if (to->to_exponential) 2711da177e4SLinus Torvalds req->rq_timeout <<= 1; 2721da177e4SLinus Torvalds else 2731da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 2741da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 2751da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 2761da177e4SLinus Torvalds req->rq_retries++; 2771da177e4SLinus Torvalds pprintk("RPC: %lu retrans\n", jiffies); 2781da177e4SLinus Torvalds } else { 2791da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 2801da177e4SLinus Torvalds req->rq_retries = 0; 2811da177e4SLinus Torvalds xprt_reset_majortimeo(req); 2821da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 2834a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 2841da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 2854a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2861da177e4SLinus Torvalds pprintk("RPC: %lu timeout\n", jiffies); 2871da177e4SLinus Torvalds status = -ETIMEDOUT; 2881da177e4SLinus Torvalds } 2891da177e4SLinus Torvalds 2901da177e4SLinus Torvalds if (req->rq_timeout == 0) { 2911da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 2921da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 2931da177e4SLinus Torvalds } 2941da177e4SLinus Torvalds return status; 2951da177e4SLinus Torvalds } 2961da177e4SLinus Torvalds 29755aa4f58SChuck Lever static void xprt_autoclose(void *args) 2981da177e4SLinus Torvalds { 2991da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)args; 3001da177e4SLinus Torvalds 3011da177e4SLinus Torvalds xprt_disconnect(xprt); 302a246b010SChuck Lever xprt->ops->close(xprt); 3031da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 3041da177e4SLinus Torvalds } 3051da177e4SLinus Torvalds 3069903cd1cSChuck Lever /** 3079903cd1cSChuck Lever * xprt_disconnect - mark a transport as disconnected 3089903cd1cSChuck Lever * @xprt: transport to flag for disconnect 3099903cd1cSChuck Lever * 3101da177e4SLinus Torvalds */ 311a246b010SChuck Lever void xprt_disconnect(struct rpc_xprt *xprt) 3121da177e4SLinus Torvalds { 3131da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 3144a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 3151da177e4SLinus Torvalds xprt_clear_connected(xprt); 31644fbac22SChuck Lever xprt_wake_pending_tasks(xprt, -ENOTCONN); 3174a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3181da177e4SLinus Torvalds } 3191da177e4SLinus Torvalds 3201da177e4SLinus Torvalds static void 3211da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 3221da177e4SLinus Torvalds { 3231da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 3241da177e4SLinus Torvalds 3254a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 3261da177e4SLinus Torvalds if (!list_empty(&xprt->recv) || xprt->shutdown) 3271da177e4SLinus Torvalds goto out_abort; 3282226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 3291da177e4SLinus Torvalds goto out_abort; 3304a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 3312226feb6SChuck Lever if (xprt_connecting(xprt)) 3321da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 3331da177e4SLinus Torvalds else 3341da177e4SLinus Torvalds schedule_work(&xprt->task_cleanup); 3351da177e4SLinus Torvalds return; 3361da177e4SLinus Torvalds out_abort: 3374a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 3381da177e4SLinus Torvalds } 3391da177e4SLinus Torvalds 3409903cd1cSChuck Lever /** 3419903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 3429903cd1cSChuck Lever * @task: RPC task that is requesting the connect 3431da177e4SLinus Torvalds * 3441da177e4SLinus Torvalds */ 3451da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 3461da177e4SLinus Torvalds { 3471da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 3481da177e4SLinus Torvalds 3491da177e4SLinus Torvalds dprintk("RPC: %4d xprt_connect xprt %p %s connected\n", task->tk_pid, 3501da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 3511da177e4SLinus Torvalds 3521da177e4SLinus Torvalds if (xprt->shutdown) { 3531da177e4SLinus Torvalds task->tk_status = -EIO; 3541da177e4SLinus Torvalds return; 3551da177e4SLinus Torvalds } 3561da177e4SLinus Torvalds if (!xprt->addr.sin_port) { 3571da177e4SLinus Torvalds task->tk_status = -EIO; 3581da177e4SLinus Torvalds return; 3591da177e4SLinus Torvalds } 3601da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 3611da177e4SLinus Torvalds return; 3621da177e4SLinus Torvalds if (xprt_connected(xprt)) 363a246b010SChuck Lever xprt_release_write(xprt, task); 364a246b010SChuck Lever else { 3651da177e4SLinus Torvalds if (task->tk_rqstp) 3661da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 3671da177e4SLinus Torvalds 3681da177e4SLinus Torvalds task->tk_timeout = RPC_CONNECT_TIMEOUT; 3691da177e4SLinus Torvalds rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL); 370a246b010SChuck Lever xprt->ops->connect(task); 3711da177e4SLinus Torvalds } 3721da177e4SLinus Torvalds return; 3731da177e4SLinus Torvalds } 3741da177e4SLinus Torvalds 3759903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 3761da177e4SLinus Torvalds { 3771da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 3781da177e4SLinus Torvalds 3791da177e4SLinus Torvalds if (task->tk_status >= 0) { 3801da177e4SLinus Torvalds dprintk("RPC: %4d xprt_connect_status: connection established\n", 3811da177e4SLinus Torvalds task->tk_pid); 3821da177e4SLinus Torvalds return; 3831da177e4SLinus Torvalds } 3841da177e4SLinus Torvalds 3851da177e4SLinus Torvalds switch (task->tk_status) { 3861da177e4SLinus Torvalds case -ECONNREFUSED: 3871da177e4SLinus Torvalds case -ECONNRESET: 38823475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: server %s refused connection\n", 38923475d66SChuck Lever task->tk_pid, task->tk_client->cl_server); 39023475d66SChuck Lever break; 3911da177e4SLinus Torvalds case -ENOTCONN: 39223475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: connection broken\n", 39323475d66SChuck Lever task->tk_pid); 39423475d66SChuck Lever break; 3951da177e4SLinus Torvalds case -ETIMEDOUT: 39623475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: connect attempt timed out\n", 3971da177e4SLinus Torvalds task->tk_pid); 3981da177e4SLinus Torvalds break; 3991da177e4SLinus Torvalds default: 40023475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: error %d connecting to server %s\n", 40123475d66SChuck Lever task->tk_pid, -task->tk_status, task->tk_client->cl_server); 4021da177e4SLinus Torvalds xprt_release_write(xprt, task); 40323475d66SChuck Lever task->tk_status = -EIO; 40423475d66SChuck Lever return; 40523475d66SChuck Lever } 40623475d66SChuck Lever 40723475d66SChuck Lever /* if soft mounted, just cause this RPC to fail */ 40823475d66SChuck Lever if (RPC_IS_SOFT(task)) { 40923475d66SChuck Lever xprt_release_write(xprt, task); 41023475d66SChuck Lever task->tk_status = -EIO; 41123475d66SChuck Lever } 4121da177e4SLinus Torvalds } 4131da177e4SLinus Torvalds 4149903cd1cSChuck Lever /** 4159903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 4169903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 4179903cd1cSChuck Lever * @xid: RPC XID of incoming reply 4189903cd1cSChuck Lever * 4191da177e4SLinus Torvalds */ 420a246b010SChuck Lever struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid) 4211da177e4SLinus Torvalds { 4221da177e4SLinus Torvalds struct list_head *pos; 4231da177e4SLinus Torvalds struct rpc_rqst *req = NULL; 4241da177e4SLinus Torvalds 4251da177e4SLinus Torvalds list_for_each(pos, &xprt->recv) { 4261da177e4SLinus Torvalds struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); 4271da177e4SLinus Torvalds if (entry->rq_xid == xid) { 4281da177e4SLinus Torvalds req = entry; 4291da177e4SLinus Torvalds break; 4301da177e4SLinus Torvalds } 4311da177e4SLinus Torvalds } 4321da177e4SLinus Torvalds return req; 4331da177e4SLinus Torvalds } 4341da177e4SLinus Torvalds 4359903cd1cSChuck Lever /** 4369903cd1cSChuck Lever * xprt_complete_rqst - called when reply processing is complete 4379903cd1cSChuck Lever * @xprt: controlling transport 4389903cd1cSChuck Lever * @req: RPC request that just completed 4399903cd1cSChuck Lever * @copied: actual number of bytes received from the transport 4409903cd1cSChuck Lever * 4411da177e4SLinus Torvalds */ 442a246b010SChuck Lever void xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied) 4431da177e4SLinus Torvalds { 4441da177e4SLinus Torvalds struct rpc_task *task = req->rq_task; 4451da177e4SLinus Torvalds struct rpc_clnt *clnt = task->tk_client; 4461da177e4SLinus Torvalds 4471da177e4SLinus Torvalds /* Adjust congestion window */ 4481da177e4SLinus Torvalds if (!xprt->nocong) { 4491da177e4SLinus Torvalds unsigned timer = task->tk_msg.rpc_proc->p_timer; 4501da177e4SLinus Torvalds xprt_adjust_cwnd(xprt, copied); 4511da177e4SLinus Torvalds __xprt_put_cong(xprt, req); 4521da177e4SLinus Torvalds if (timer) { 4531da177e4SLinus Torvalds if (req->rq_ntrans == 1) 4541da177e4SLinus Torvalds rpc_update_rtt(clnt->cl_rtt, timer, 4551da177e4SLinus Torvalds (long)jiffies - req->rq_xtime); 4561da177e4SLinus Torvalds rpc_set_timeo(clnt->cl_rtt, timer, req->rq_ntrans - 1); 4571da177e4SLinus Torvalds } 4581da177e4SLinus Torvalds } 4591da177e4SLinus Torvalds 4601da177e4SLinus Torvalds #ifdef RPC_PROFILE 4611da177e4SLinus Torvalds /* Profile only reads for now */ 4621da177e4SLinus Torvalds if (copied > 1024) { 4631da177e4SLinus Torvalds static unsigned long nextstat; 4641da177e4SLinus Torvalds static unsigned long pkt_rtt, pkt_len, pkt_cnt; 4651da177e4SLinus Torvalds 4661da177e4SLinus Torvalds pkt_cnt++; 4671da177e4SLinus Torvalds pkt_len += req->rq_slen + copied; 4681da177e4SLinus Torvalds pkt_rtt += jiffies - req->rq_xtime; 4691da177e4SLinus Torvalds if (time_before(nextstat, jiffies)) { 4701da177e4SLinus Torvalds printk("RPC: %lu %ld cwnd\n", jiffies, xprt->cwnd); 4711da177e4SLinus Torvalds printk("RPC: %ld %ld %ld %ld stat\n", 4721da177e4SLinus Torvalds jiffies, pkt_cnt, pkt_len, pkt_rtt); 4731da177e4SLinus Torvalds pkt_rtt = pkt_len = pkt_cnt = 0; 4741da177e4SLinus Torvalds nextstat = jiffies + 5 * HZ; 4751da177e4SLinus Torvalds } 4761da177e4SLinus Torvalds } 4771da177e4SLinus Torvalds #endif 4781da177e4SLinus Torvalds 4791da177e4SLinus Torvalds dprintk("RPC: %4d has input (%d bytes)\n", task->tk_pid, copied); 4801da177e4SLinus Torvalds list_del_init(&req->rq_list); 4811da177e4SLinus Torvalds req->rq_received = req->rq_private_buf.len = copied; 4821da177e4SLinus Torvalds 4831da177e4SLinus Torvalds /* ... and wake up the process. */ 4841da177e4SLinus Torvalds rpc_wake_up_task(task); 4851da177e4SLinus Torvalds return; 4861da177e4SLinus Torvalds } 4871da177e4SLinus Torvalds 4881da177e4SLinus Torvalds /* 4891da177e4SLinus Torvalds * RPC receive timeout handler. 4901da177e4SLinus Torvalds */ 4911da177e4SLinus Torvalds static void 4921da177e4SLinus Torvalds xprt_timer(struct rpc_task *task) 4931da177e4SLinus Torvalds { 4941da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 4951da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 4961da177e4SLinus Torvalds 4974a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 4981da177e4SLinus Torvalds if (req->rq_received) 4991da177e4SLinus Torvalds goto out; 5001da177e4SLinus Torvalds 5011da177e4SLinus Torvalds xprt_adjust_cwnd(req->rq_xprt, -ETIMEDOUT); 5021da177e4SLinus Torvalds __xprt_put_cong(xprt, req); 5031da177e4SLinus Torvalds 5041da177e4SLinus Torvalds dprintk("RPC: %4d xprt_timer (%s request)\n", 5051da177e4SLinus Torvalds task->tk_pid, req ? "pending" : "backlogged"); 5061da177e4SLinus Torvalds 5071da177e4SLinus Torvalds task->tk_status = -ETIMEDOUT; 5081da177e4SLinus Torvalds out: 5091da177e4SLinus Torvalds task->tk_timeout = 0; 5101da177e4SLinus Torvalds rpc_wake_up_task(task); 5114a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 5121da177e4SLinus Torvalds } 5131da177e4SLinus Torvalds 5149903cd1cSChuck Lever /** 5159903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 5169903cd1cSChuck Lever * @task: RPC task about to send a request 5179903cd1cSChuck Lever * 5181da177e4SLinus Torvalds */ 5199903cd1cSChuck Lever int xprt_prepare_transmit(struct rpc_task *task) 5201da177e4SLinus Torvalds { 5211da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 5221da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 5231da177e4SLinus Torvalds int err = 0; 5241da177e4SLinus Torvalds 5251da177e4SLinus Torvalds dprintk("RPC: %4d xprt_prepare_transmit\n", task->tk_pid); 5261da177e4SLinus Torvalds 5271da177e4SLinus Torvalds if (xprt->shutdown) 5281da177e4SLinus Torvalds return -EIO; 5291da177e4SLinus Torvalds 5304a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5311da177e4SLinus Torvalds if (req->rq_received && !req->rq_bytes_sent) { 5321da177e4SLinus Torvalds err = req->rq_received; 5331da177e4SLinus Torvalds goto out_unlock; 5341da177e4SLinus Torvalds } 5351da177e4SLinus Torvalds if (!__xprt_lock_write(xprt, task)) { 5361da177e4SLinus Torvalds err = -EAGAIN; 5371da177e4SLinus Torvalds goto out_unlock; 5381da177e4SLinus Torvalds } 5391da177e4SLinus Torvalds 5401da177e4SLinus Torvalds if (!xprt_connected(xprt)) { 5411da177e4SLinus Torvalds err = -ENOTCONN; 5421da177e4SLinus Torvalds goto out_unlock; 5431da177e4SLinus Torvalds } 5441da177e4SLinus Torvalds out_unlock: 5454a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5461da177e4SLinus Torvalds return err; 5471da177e4SLinus Torvalds } 5481da177e4SLinus Torvalds 5499903cd1cSChuck Lever /** 5509903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 5519903cd1cSChuck Lever * @task: controlling RPC task 5529903cd1cSChuck Lever * 5539903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 5549903cd1cSChuck Lever */ 5559903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 5561da177e4SLinus Torvalds { 5571da177e4SLinus Torvalds struct rpc_clnt *clnt = task->tk_client; 5581da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 5591da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 560a246b010SChuck Lever int status; 5611da177e4SLinus Torvalds 5621da177e4SLinus Torvalds dprintk("RPC: %4d xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 5631da177e4SLinus Torvalds 5641da177e4SLinus Torvalds smp_rmb(); 5651da177e4SLinus Torvalds if (!req->rq_received) { 5661da177e4SLinus Torvalds if (list_empty(&req->rq_list)) { 5674a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5681da177e4SLinus Torvalds /* Update the softirq receive buffer */ 5691da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 5701da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 5711da177e4SLinus Torvalds /* Add request to the receive list */ 5721da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 5734a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5741da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5750f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 5760f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 5771da177e4SLinus Torvalds } 5781da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 5791da177e4SLinus Torvalds return; 5801da177e4SLinus Torvalds 581a246b010SChuck Lever status = xprt->ops->send_request(task); 582a246b010SChuck Lever if (!status) 5831da177e4SLinus Torvalds goto out_receive; 5841da177e4SLinus Torvalds 5851da177e4SLinus Torvalds /* Note: at this point, task->tk_sleeping has not yet been set, 5861da177e4SLinus Torvalds * hence there is no danger of the waking up task being put on 5871da177e4SLinus Torvalds * schedq, and being picked up by a parallel run of rpciod(). 5881da177e4SLinus Torvalds */ 5891da177e4SLinus Torvalds task->tk_status = status; 5901da177e4SLinus Torvalds 5911da177e4SLinus Torvalds switch (status) { 5921da177e4SLinus Torvalds case -ECONNREFUSED: 5931da177e4SLinus Torvalds task->tk_timeout = RPC_REESTABLISH_TIMEOUT; 5941da177e4SLinus Torvalds rpc_sleep_on(&xprt->sending, task, NULL, NULL); 595a246b010SChuck Lever case -EAGAIN: 5961da177e4SLinus Torvalds case -ENOTCONN: 5971da177e4SLinus Torvalds return; 5981da177e4SLinus Torvalds default: 5991da177e4SLinus Torvalds if (xprt->stream) 6001da177e4SLinus Torvalds xprt_disconnect(xprt); 6011da177e4SLinus Torvalds } 6021da177e4SLinus Torvalds xprt_release_write(xprt, task); 6031da177e4SLinus Torvalds return; 6041da177e4SLinus Torvalds out_receive: 6051da177e4SLinus Torvalds dprintk("RPC: %4d xmit complete\n", task->tk_pid); 6061da177e4SLinus Torvalds /* Set the task's receive timeout value */ 6074a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6081da177e4SLinus Torvalds if (!xprt->nocong) { 6091da177e4SLinus Torvalds int timer = task->tk_msg.rpc_proc->p_timer; 6101da177e4SLinus Torvalds task->tk_timeout = rpc_calc_rto(clnt->cl_rtt, timer); 6111da177e4SLinus Torvalds task->tk_timeout <<= rpc_ntimeo(clnt->cl_rtt, timer) + req->rq_retries; 6121da177e4SLinus Torvalds if (task->tk_timeout > xprt->timeout.to_maxval || task->tk_timeout == 0) 6131da177e4SLinus Torvalds task->tk_timeout = xprt->timeout.to_maxval; 6141da177e4SLinus Torvalds } else 6151da177e4SLinus Torvalds task->tk_timeout = req->rq_timeout; 6161da177e4SLinus Torvalds /* Don't race with disconnect */ 6171da177e4SLinus Torvalds if (!xprt_connected(xprt)) 6181da177e4SLinus Torvalds task->tk_status = -ENOTCONN; 6191da177e4SLinus Torvalds else if (!req->rq_received) 6201da177e4SLinus Torvalds rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer); 6211da177e4SLinus Torvalds __xprt_release_write(xprt, task); 6224a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6231da177e4SLinus Torvalds } 6241da177e4SLinus Torvalds 6259903cd1cSChuck Lever static inline void do_xprt_reserve(struct rpc_task *task) 6261da177e4SLinus Torvalds { 6271da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6281da177e4SLinus Torvalds 6291da177e4SLinus Torvalds task->tk_status = 0; 6301da177e4SLinus Torvalds if (task->tk_rqstp) 6311da177e4SLinus Torvalds return; 6321da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 6331da177e4SLinus Torvalds struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 6341da177e4SLinus Torvalds list_del_init(&req->rq_list); 6351da177e4SLinus Torvalds task->tk_rqstp = req; 6361da177e4SLinus Torvalds xprt_request_init(task, xprt); 6371da177e4SLinus Torvalds return; 6381da177e4SLinus Torvalds } 6391da177e4SLinus Torvalds dprintk("RPC: waiting for request slot\n"); 6401da177e4SLinus Torvalds task->tk_status = -EAGAIN; 6411da177e4SLinus Torvalds task->tk_timeout = 0; 6421da177e4SLinus Torvalds rpc_sleep_on(&xprt->backlog, task, NULL, NULL); 6431da177e4SLinus Torvalds } 6441da177e4SLinus Torvalds 6459903cd1cSChuck Lever /** 6469903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 6479903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 6489903cd1cSChuck Lever * 6499903cd1cSChuck Lever * If no more slots are available, place the task on the transport's 6509903cd1cSChuck Lever * backlog queue. 6519903cd1cSChuck Lever */ 6529903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 6531da177e4SLinus Torvalds { 6541da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6551da177e4SLinus Torvalds 6561da177e4SLinus Torvalds task->tk_status = -EIO; 6571da177e4SLinus Torvalds if (!xprt->shutdown) { 6585dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 6591da177e4SLinus Torvalds do_xprt_reserve(task); 6605dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 6611da177e4SLinus Torvalds } 6621da177e4SLinus Torvalds } 6631da177e4SLinus Torvalds 6641da177e4SLinus Torvalds static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt) 6651da177e4SLinus Torvalds { 6661da177e4SLinus Torvalds return xprt->xid++; 6671da177e4SLinus Torvalds } 6681da177e4SLinus Torvalds 6691da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 6701da177e4SLinus Torvalds { 6711da177e4SLinus Torvalds get_random_bytes(&xprt->xid, sizeof(xprt->xid)); 6721da177e4SLinus Torvalds } 6731da177e4SLinus Torvalds 6749903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 6751da177e4SLinus Torvalds { 6761da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 6771da177e4SLinus Torvalds 6781da177e4SLinus Torvalds req->rq_timeout = xprt->timeout.to_initval; 6791da177e4SLinus Torvalds req->rq_task = task; 6801da177e4SLinus Torvalds req->rq_xprt = xprt; 6811da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 6821da177e4SLinus Torvalds dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid, 6831da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 6841da177e4SLinus Torvalds } 6851da177e4SLinus Torvalds 6869903cd1cSChuck Lever /** 6879903cd1cSChuck Lever * xprt_release - release an RPC request slot 6889903cd1cSChuck Lever * @task: task which is finished with the slot 6899903cd1cSChuck Lever * 6901da177e4SLinus Torvalds */ 6919903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 6921da177e4SLinus Torvalds { 6931da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6941da177e4SLinus Torvalds struct rpc_rqst *req; 6951da177e4SLinus Torvalds 6961da177e4SLinus Torvalds if (!(req = task->tk_rqstp)) 6971da177e4SLinus Torvalds return; 6984a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6991da177e4SLinus Torvalds __xprt_release_write(xprt, task); 7001da177e4SLinus Torvalds __xprt_put_cong(xprt, req); 7011da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 7021da177e4SLinus Torvalds list_del(&req->rq_list); 7031da177e4SLinus Torvalds xprt->last_used = jiffies; 7041da177e4SLinus Torvalds if (list_empty(&xprt->recv) && !xprt->shutdown) 705a246b010SChuck Lever mod_timer(&xprt->timer, 706a246b010SChuck Lever xprt->last_used + RPC_IDLE_DISCONNECT_TIMEOUT); 7074a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 7081da177e4SLinus Torvalds task->tk_rqstp = NULL; 7091da177e4SLinus Torvalds memset(req, 0, sizeof(*req)); /* mark unused */ 7101da177e4SLinus Torvalds 7111da177e4SLinus Torvalds dprintk("RPC: %4d release request %p\n", task->tk_pid, req); 7121da177e4SLinus Torvalds 7135dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 7141da177e4SLinus Torvalds list_add(&req->rq_list, &xprt->free); 7151da177e4SLinus Torvalds xprt_clear_backlog(xprt); 7165dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 7171da177e4SLinus Torvalds } 7181da177e4SLinus Torvalds 7199903cd1cSChuck Lever /** 7209903cd1cSChuck Lever * xprt_set_timeout - set constant RPC timeout 7219903cd1cSChuck Lever * @to: RPC timeout parameters to set up 7229903cd1cSChuck Lever * @retr: number of retries 7239903cd1cSChuck Lever * @incr: amount of increase after each retry 7249903cd1cSChuck Lever * 7251da177e4SLinus Torvalds */ 7269903cd1cSChuck Lever void xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr) 7271da177e4SLinus Torvalds { 7281da177e4SLinus Torvalds to->to_initval = 7291da177e4SLinus Torvalds to->to_increment = incr; 730eab5c084SChuck Lever to->to_maxval = to->to_initval + (incr * retr); 7311da177e4SLinus Torvalds to->to_retries = retr; 7321da177e4SLinus Torvalds to->to_exponential = 0; 7331da177e4SLinus Torvalds } 7341da177e4SLinus Torvalds 7359903cd1cSChuck Lever static struct rpc_xprt *xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to) 7361da177e4SLinus Torvalds { 737a246b010SChuck Lever int result; 7381da177e4SLinus Torvalds struct rpc_xprt *xprt; 7391da177e4SLinus Torvalds struct rpc_rqst *req; 7401da177e4SLinus Torvalds 7411da177e4SLinus Torvalds if ((xprt = kmalloc(sizeof(struct rpc_xprt), GFP_KERNEL)) == NULL) 7421da177e4SLinus Torvalds return ERR_PTR(-ENOMEM); 7431da177e4SLinus Torvalds memset(xprt, 0, sizeof(*xprt)); /* Nnnngh! */ 7441da177e4SLinus Torvalds 7451da177e4SLinus Torvalds xprt->addr = *ap; 746a246b010SChuck Lever 747a246b010SChuck Lever switch (proto) { 748a246b010SChuck Lever case IPPROTO_UDP: 749a246b010SChuck Lever result = xs_setup_udp(xprt, to); 750a246b010SChuck Lever break; 751a246b010SChuck Lever case IPPROTO_TCP: 752a246b010SChuck Lever result = xs_setup_tcp(xprt, to); 753a246b010SChuck Lever break; 754a246b010SChuck Lever default: 755a246b010SChuck Lever printk(KERN_ERR "RPC: unrecognized transport protocol: %d\n", 756a246b010SChuck Lever proto); 757a246b010SChuck Lever result = -EIO; 758a246b010SChuck Lever break; 7591da177e4SLinus Torvalds } 760a246b010SChuck Lever if (result) { 761a246b010SChuck Lever kfree(xprt); 762a246b010SChuck Lever return ERR_PTR(result); 763a246b010SChuck Lever } 764a246b010SChuck Lever 7654a0f8c04SChuck Lever spin_lock_init(&xprt->transport_lock); 7665dc07727SChuck Lever spin_lock_init(&xprt->reserve_lock); 7671da177e4SLinus Torvalds init_waitqueue_head(&xprt->cong_wait); 7681da177e4SLinus Torvalds 7691da177e4SLinus Torvalds INIT_LIST_HEAD(&xprt->free); 7701da177e4SLinus Torvalds INIT_LIST_HEAD(&xprt->recv); 77155aa4f58SChuck Lever INIT_WORK(&xprt->task_cleanup, xprt_autoclose, xprt); 7721da177e4SLinus Torvalds init_timer(&xprt->timer); 7731da177e4SLinus Torvalds xprt->timer.function = xprt_init_autodisconnect; 7741da177e4SLinus Torvalds xprt->timer.data = (unsigned long) xprt; 7751da177e4SLinus Torvalds xprt->last_used = jiffies; 7761da177e4SLinus Torvalds 7771da177e4SLinus Torvalds rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 7781da177e4SLinus Torvalds rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 7791da177e4SLinus Torvalds rpc_init_wait_queue(&xprt->resend, "xprt_resend"); 7801da177e4SLinus Torvalds rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 7811da177e4SLinus Torvalds 7821da177e4SLinus Torvalds /* initialize free list */ 783a246b010SChuck Lever for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) 7841da177e4SLinus Torvalds list_add(&req->rq_list, &xprt->free); 7851da177e4SLinus Torvalds 7861da177e4SLinus Torvalds xprt_init_xid(xprt); 7871da177e4SLinus Torvalds 7881da177e4SLinus Torvalds dprintk("RPC: created transport %p with %u slots\n", xprt, 7891da177e4SLinus Torvalds xprt->max_reqs); 7901da177e4SLinus Torvalds 7911da177e4SLinus Torvalds return xprt; 7921da177e4SLinus Torvalds } 7931da177e4SLinus Torvalds 7949903cd1cSChuck Lever /** 7959903cd1cSChuck Lever * xprt_create_proto - create an RPC client transport 7969903cd1cSChuck Lever * @proto: requested transport protocol 7979903cd1cSChuck Lever * @sap: remote peer's address 7989903cd1cSChuck Lever * @to: timeout parameters for new transport 7999903cd1cSChuck Lever * 8001da177e4SLinus Torvalds */ 8019903cd1cSChuck Lever struct rpc_xprt *xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to) 8021da177e4SLinus Torvalds { 8031da177e4SLinus Torvalds struct rpc_xprt *xprt; 8041da177e4SLinus Torvalds 8051da177e4SLinus Torvalds xprt = xprt_setup(proto, sap, to); 8061da177e4SLinus Torvalds if (IS_ERR(xprt)) 8071da177e4SLinus Torvalds dprintk("RPC: xprt_create_proto failed\n"); 8081da177e4SLinus Torvalds else 8091da177e4SLinus Torvalds dprintk("RPC: xprt_create_proto created xprt %p\n", xprt); 8101da177e4SLinus Torvalds return xprt; 8111da177e4SLinus Torvalds } 8121da177e4SLinus Torvalds 8139903cd1cSChuck Lever static void xprt_shutdown(struct rpc_xprt *xprt) 8141da177e4SLinus Torvalds { 8151da177e4SLinus Torvalds xprt->shutdown = 1; 8161da177e4SLinus Torvalds rpc_wake_up(&xprt->sending); 8171da177e4SLinus Torvalds rpc_wake_up(&xprt->resend); 81844fbac22SChuck Lever xprt_wake_pending_tasks(xprt, -EIO); 8191da177e4SLinus Torvalds rpc_wake_up(&xprt->backlog); 8201da177e4SLinus Torvalds wake_up(&xprt->cong_wait); 8211da177e4SLinus Torvalds del_timer_sync(&xprt->timer); 8221da177e4SLinus Torvalds } 8231da177e4SLinus Torvalds 8249903cd1cSChuck Lever static int xprt_clear_backlog(struct rpc_xprt *xprt) { 8251da177e4SLinus Torvalds rpc_wake_up_next(&xprt->backlog); 8261da177e4SLinus Torvalds wake_up(&xprt->cong_wait); 8271da177e4SLinus Torvalds return 1; 8281da177e4SLinus Torvalds } 8291da177e4SLinus Torvalds 8309903cd1cSChuck Lever /** 8319903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 8329903cd1cSChuck Lever * @xprt: transport to destroy 8339903cd1cSChuck Lever * 8341da177e4SLinus Torvalds */ 8359903cd1cSChuck Lever int xprt_destroy(struct rpc_xprt *xprt) 8361da177e4SLinus Torvalds { 8371da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 8381da177e4SLinus Torvalds xprt_shutdown(xprt); 839a246b010SChuck Lever xprt->ops->destroy(xprt); 8401da177e4SLinus Torvalds kfree(xprt); 8411da177e4SLinus Torvalds 8421da177e4SLinus Torvalds return 0; 8431da177e4SLinus Torvalds } 844