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 244c7b2cae8SChuck Lever /** 245c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 246c7b2cae8SChuck Lever * @task: task to be put to sleep 247c7b2cae8SChuck Lever * 248c7b2cae8SChuck Lever */ 249c7b2cae8SChuck Lever void xprt_wait_for_buffer_space(struct rpc_task *task) 250c7b2cae8SChuck Lever { 251c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 252c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 253c7b2cae8SChuck Lever 254c7b2cae8SChuck Lever task->tk_timeout = req->rq_timeout; 255c7b2cae8SChuck Lever rpc_sleep_on(&xprt->pending, task, NULL, NULL); 256c7b2cae8SChuck Lever } 257c7b2cae8SChuck Lever 258c7b2cae8SChuck Lever /** 259c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 260c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 261c7b2cae8SChuck Lever * 262c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 263c7b2cae8SChuck Lever */ 264c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 265c7b2cae8SChuck Lever { 266c7b2cae8SChuck Lever if (unlikely(xprt->shutdown)) 267c7b2cae8SChuck Lever return; 268c7b2cae8SChuck Lever 269c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 270c7b2cae8SChuck Lever if (xprt->snd_task) { 271c7b2cae8SChuck Lever dprintk("RPC: write space: waking waiting task on xprt %p\n", 272c7b2cae8SChuck Lever xprt); 273c7b2cae8SChuck Lever rpc_wake_up_task(xprt->snd_task); 274c7b2cae8SChuck Lever } 275c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 276c7b2cae8SChuck Lever } 277c7b2cae8SChuck Lever 2781da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 2791da177e4SLinus Torvalds { 2801da177e4SLinus Torvalds struct rpc_timeout *to = &req->rq_xprt->timeout; 2811da177e4SLinus Torvalds 2821da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 2831da177e4SLinus Torvalds if (to->to_exponential) 2841da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 2851da177e4SLinus Torvalds else 2861da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 2871da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 2881da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 2891da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 2901da177e4SLinus Torvalds } 2911da177e4SLinus Torvalds 2929903cd1cSChuck Lever /** 2939903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 2949903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 2959903cd1cSChuck Lever * 2961da177e4SLinus Torvalds */ 2971da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 2981da177e4SLinus Torvalds { 2991da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 3001da177e4SLinus Torvalds struct rpc_timeout *to = &xprt->timeout; 3011da177e4SLinus Torvalds int status = 0; 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 3041da177e4SLinus Torvalds if (to->to_exponential) 3051da177e4SLinus Torvalds req->rq_timeout <<= 1; 3061da177e4SLinus Torvalds else 3071da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 3081da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 3091da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 3101da177e4SLinus Torvalds req->rq_retries++; 3111da177e4SLinus Torvalds pprintk("RPC: %lu retrans\n", jiffies); 3121da177e4SLinus Torvalds } else { 3131da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 3141da177e4SLinus Torvalds req->rq_retries = 0; 3151da177e4SLinus Torvalds xprt_reset_majortimeo(req); 3161da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 3174a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 3181da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 3194a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3201da177e4SLinus Torvalds pprintk("RPC: %lu timeout\n", jiffies); 3211da177e4SLinus Torvalds status = -ETIMEDOUT; 3221da177e4SLinus Torvalds } 3231da177e4SLinus Torvalds 3241da177e4SLinus Torvalds if (req->rq_timeout == 0) { 3251da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 3261da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 3271da177e4SLinus Torvalds } 3281da177e4SLinus Torvalds return status; 3291da177e4SLinus Torvalds } 3301da177e4SLinus Torvalds 33155aa4f58SChuck Lever static void xprt_autoclose(void *args) 3321da177e4SLinus Torvalds { 3331da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)args; 3341da177e4SLinus Torvalds 3351da177e4SLinus Torvalds xprt_disconnect(xprt); 336a246b010SChuck Lever xprt->ops->close(xprt); 3371da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 3381da177e4SLinus Torvalds } 3391da177e4SLinus Torvalds 3409903cd1cSChuck Lever /** 3419903cd1cSChuck Lever * xprt_disconnect - mark a transport as disconnected 3429903cd1cSChuck Lever * @xprt: transport to flag for disconnect 3439903cd1cSChuck Lever * 3441da177e4SLinus Torvalds */ 345a246b010SChuck Lever void xprt_disconnect(struct rpc_xprt *xprt) 3461da177e4SLinus Torvalds { 3471da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 3484a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 3491da177e4SLinus Torvalds xprt_clear_connected(xprt); 35044fbac22SChuck Lever xprt_wake_pending_tasks(xprt, -ENOTCONN); 3514a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3521da177e4SLinus Torvalds } 3531da177e4SLinus Torvalds 3541da177e4SLinus Torvalds static void 3551da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 3561da177e4SLinus Torvalds { 3571da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 3581da177e4SLinus Torvalds 3594a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 3601da177e4SLinus Torvalds if (!list_empty(&xprt->recv) || xprt->shutdown) 3611da177e4SLinus Torvalds goto out_abort; 3622226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 3631da177e4SLinus Torvalds goto out_abort; 3644a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 3652226feb6SChuck Lever if (xprt_connecting(xprt)) 3661da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 3671da177e4SLinus Torvalds else 3681da177e4SLinus Torvalds schedule_work(&xprt->task_cleanup); 3691da177e4SLinus Torvalds return; 3701da177e4SLinus Torvalds out_abort: 3714a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 3721da177e4SLinus Torvalds } 3731da177e4SLinus Torvalds 3749903cd1cSChuck Lever /** 3759903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 3769903cd1cSChuck Lever * @task: RPC task that is requesting the connect 3771da177e4SLinus Torvalds * 3781da177e4SLinus Torvalds */ 3791da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 3801da177e4SLinus Torvalds { 3811da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 3821da177e4SLinus Torvalds 3831da177e4SLinus Torvalds dprintk("RPC: %4d xprt_connect xprt %p %s connected\n", task->tk_pid, 3841da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds if (xprt->shutdown) { 3871da177e4SLinus Torvalds task->tk_status = -EIO; 3881da177e4SLinus Torvalds return; 3891da177e4SLinus Torvalds } 3901da177e4SLinus Torvalds if (!xprt->addr.sin_port) { 3911da177e4SLinus Torvalds task->tk_status = -EIO; 3921da177e4SLinus Torvalds return; 3931da177e4SLinus Torvalds } 3941da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 3951da177e4SLinus Torvalds return; 3961da177e4SLinus Torvalds if (xprt_connected(xprt)) 397a246b010SChuck Lever xprt_release_write(xprt, task); 398a246b010SChuck Lever else { 3991da177e4SLinus Torvalds if (task->tk_rqstp) 4001da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 4011da177e4SLinus Torvalds 4021da177e4SLinus Torvalds task->tk_timeout = RPC_CONNECT_TIMEOUT; 4031da177e4SLinus Torvalds rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL); 404a246b010SChuck Lever xprt->ops->connect(task); 4051da177e4SLinus Torvalds } 4061da177e4SLinus Torvalds return; 4071da177e4SLinus Torvalds } 4081da177e4SLinus Torvalds 4099903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 4101da177e4SLinus Torvalds { 4111da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 4121da177e4SLinus Torvalds 4131da177e4SLinus Torvalds if (task->tk_status >= 0) { 4141da177e4SLinus Torvalds dprintk("RPC: %4d xprt_connect_status: connection established\n", 4151da177e4SLinus Torvalds task->tk_pid); 4161da177e4SLinus Torvalds return; 4171da177e4SLinus Torvalds } 4181da177e4SLinus Torvalds 4191da177e4SLinus Torvalds switch (task->tk_status) { 4201da177e4SLinus Torvalds case -ECONNREFUSED: 4211da177e4SLinus Torvalds case -ECONNRESET: 42223475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: server %s refused connection\n", 42323475d66SChuck Lever task->tk_pid, task->tk_client->cl_server); 42423475d66SChuck Lever break; 4251da177e4SLinus Torvalds case -ENOTCONN: 42623475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: connection broken\n", 42723475d66SChuck Lever task->tk_pid); 42823475d66SChuck Lever break; 4291da177e4SLinus Torvalds case -ETIMEDOUT: 43023475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: connect attempt timed out\n", 4311da177e4SLinus Torvalds task->tk_pid); 4321da177e4SLinus Torvalds break; 4331da177e4SLinus Torvalds default: 43423475d66SChuck Lever dprintk("RPC: %4d xprt_connect_status: error %d connecting to server %s\n", 43523475d66SChuck Lever task->tk_pid, -task->tk_status, task->tk_client->cl_server); 4361da177e4SLinus Torvalds xprt_release_write(xprt, task); 43723475d66SChuck Lever task->tk_status = -EIO; 43823475d66SChuck Lever return; 43923475d66SChuck Lever } 44023475d66SChuck Lever 44123475d66SChuck Lever /* if soft mounted, just cause this RPC to fail */ 44223475d66SChuck Lever if (RPC_IS_SOFT(task)) { 44323475d66SChuck Lever xprt_release_write(xprt, task); 44423475d66SChuck Lever task->tk_status = -EIO; 44523475d66SChuck Lever } 4461da177e4SLinus Torvalds } 4471da177e4SLinus Torvalds 4489903cd1cSChuck Lever /** 4499903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 4509903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 4519903cd1cSChuck Lever * @xid: RPC XID of incoming reply 4529903cd1cSChuck Lever * 4531da177e4SLinus Torvalds */ 454a246b010SChuck Lever struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, u32 xid) 4551da177e4SLinus Torvalds { 4561da177e4SLinus Torvalds struct list_head *pos; 4571da177e4SLinus Torvalds struct rpc_rqst *req = NULL; 4581da177e4SLinus Torvalds 4591da177e4SLinus Torvalds list_for_each(pos, &xprt->recv) { 4601da177e4SLinus Torvalds struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); 4611da177e4SLinus Torvalds if (entry->rq_xid == xid) { 4621da177e4SLinus Torvalds req = entry; 4631da177e4SLinus Torvalds break; 4641da177e4SLinus Torvalds } 4651da177e4SLinus Torvalds } 4661da177e4SLinus Torvalds return req; 4671da177e4SLinus Torvalds } 4681da177e4SLinus Torvalds 4699903cd1cSChuck Lever /** 4709903cd1cSChuck Lever * xprt_complete_rqst - called when reply processing is complete 4719903cd1cSChuck Lever * @xprt: controlling transport 4729903cd1cSChuck Lever * @req: RPC request that just completed 4739903cd1cSChuck Lever * @copied: actual number of bytes received from the transport 4749903cd1cSChuck Lever * 4751da177e4SLinus Torvalds */ 476a246b010SChuck Lever void xprt_complete_rqst(struct rpc_xprt *xprt, struct rpc_rqst *req, int copied) 4771da177e4SLinus Torvalds { 4781da177e4SLinus Torvalds struct rpc_task *task = req->rq_task; 4791da177e4SLinus Torvalds struct rpc_clnt *clnt = task->tk_client; 4801da177e4SLinus Torvalds 4811da177e4SLinus Torvalds /* Adjust congestion window */ 4821da177e4SLinus Torvalds if (!xprt->nocong) { 4831da177e4SLinus Torvalds unsigned timer = task->tk_msg.rpc_proc->p_timer; 4841da177e4SLinus Torvalds xprt_adjust_cwnd(xprt, copied); 4851da177e4SLinus Torvalds __xprt_put_cong(xprt, req); 4861da177e4SLinus Torvalds if (timer) { 4871da177e4SLinus Torvalds if (req->rq_ntrans == 1) 4881da177e4SLinus Torvalds rpc_update_rtt(clnt->cl_rtt, timer, 4891da177e4SLinus Torvalds (long)jiffies - req->rq_xtime); 4901da177e4SLinus Torvalds rpc_set_timeo(clnt->cl_rtt, timer, req->rq_ntrans - 1); 4911da177e4SLinus Torvalds } 4921da177e4SLinus Torvalds } 4931da177e4SLinus Torvalds 4941da177e4SLinus Torvalds #ifdef RPC_PROFILE 4951da177e4SLinus Torvalds /* Profile only reads for now */ 4961da177e4SLinus Torvalds if (copied > 1024) { 4971da177e4SLinus Torvalds static unsigned long nextstat; 4981da177e4SLinus Torvalds static unsigned long pkt_rtt, pkt_len, pkt_cnt; 4991da177e4SLinus Torvalds 5001da177e4SLinus Torvalds pkt_cnt++; 5011da177e4SLinus Torvalds pkt_len += req->rq_slen + copied; 5021da177e4SLinus Torvalds pkt_rtt += jiffies - req->rq_xtime; 5031da177e4SLinus Torvalds if (time_before(nextstat, jiffies)) { 5041da177e4SLinus Torvalds printk("RPC: %lu %ld cwnd\n", jiffies, xprt->cwnd); 5051da177e4SLinus Torvalds printk("RPC: %ld %ld %ld %ld stat\n", 5061da177e4SLinus Torvalds jiffies, pkt_cnt, pkt_len, pkt_rtt); 5071da177e4SLinus Torvalds pkt_rtt = pkt_len = pkt_cnt = 0; 5081da177e4SLinus Torvalds nextstat = jiffies + 5 * HZ; 5091da177e4SLinus Torvalds } 5101da177e4SLinus Torvalds } 5111da177e4SLinus Torvalds #endif 5121da177e4SLinus Torvalds 5131da177e4SLinus Torvalds dprintk("RPC: %4d has input (%d bytes)\n", task->tk_pid, copied); 5141da177e4SLinus Torvalds list_del_init(&req->rq_list); 5151da177e4SLinus Torvalds req->rq_received = req->rq_private_buf.len = copied; 5161da177e4SLinus Torvalds 5171da177e4SLinus Torvalds /* ... and wake up the process. */ 5181da177e4SLinus Torvalds rpc_wake_up_task(task); 5191da177e4SLinus Torvalds return; 5201da177e4SLinus Torvalds } 5211da177e4SLinus Torvalds 5221da177e4SLinus Torvalds /* 5231da177e4SLinus Torvalds * RPC receive timeout handler. 5241da177e4SLinus Torvalds */ 5251da177e4SLinus Torvalds static void 5261da177e4SLinus Torvalds xprt_timer(struct rpc_task *task) 5271da177e4SLinus Torvalds { 5281da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 5291da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 5301da177e4SLinus Torvalds 5314a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 5321da177e4SLinus Torvalds if (req->rq_received) 5331da177e4SLinus Torvalds goto out; 5341da177e4SLinus Torvalds 5351da177e4SLinus Torvalds xprt_adjust_cwnd(req->rq_xprt, -ETIMEDOUT); 5361da177e4SLinus Torvalds __xprt_put_cong(xprt, req); 5371da177e4SLinus Torvalds 5381da177e4SLinus Torvalds dprintk("RPC: %4d xprt_timer (%s request)\n", 5391da177e4SLinus Torvalds task->tk_pid, req ? "pending" : "backlogged"); 5401da177e4SLinus Torvalds 5411da177e4SLinus Torvalds task->tk_status = -ETIMEDOUT; 5421da177e4SLinus Torvalds out: 5431da177e4SLinus Torvalds task->tk_timeout = 0; 5441da177e4SLinus Torvalds rpc_wake_up_task(task); 5454a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 5461da177e4SLinus Torvalds } 5471da177e4SLinus Torvalds 5489903cd1cSChuck Lever /** 5499903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 5509903cd1cSChuck Lever * @task: RPC task about to send a request 5519903cd1cSChuck Lever * 5521da177e4SLinus Torvalds */ 5539903cd1cSChuck Lever int xprt_prepare_transmit(struct rpc_task *task) 5541da177e4SLinus Torvalds { 5551da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 5561da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 5571da177e4SLinus Torvalds int err = 0; 5581da177e4SLinus Torvalds 5591da177e4SLinus Torvalds dprintk("RPC: %4d xprt_prepare_transmit\n", task->tk_pid); 5601da177e4SLinus Torvalds 5611da177e4SLinus Torvalds if (xprt->shutdown) 5621da177e4SLinus Torvalds return -EIO; 5631da177e4SLinus Torvalds 5644a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5651da177e4SLinus Torvalds if (req->rq_received && !req->rq_bytes_sent) { 5661da177e4SLinus Torvalds err = req->rq_received; 5671da177e4SLinus Torvalds goto out_unlock; 5681da177e4SLinus Torvalds } 5691da177e4SLinus Torvalds if (!__xprt_lock_write(xprt, task)) { 5701da177e4SLinus Torvalds err = -EAGAIN; 5711da177e4SLinus Torvalds goto out_unlock; 5721da177e4SLinus Torvalds } 5731da177e4SLinus Torvalds 5741da177e4SLinus Torvalds if (!xprt_connected(xprt)) { 5751da177e4SLinus Torvalds err = -ENOTCONN; 5761da177e4SLinus Torvalds goto out_unlock; 5771da177e4SLinus Torvalds } 5781da177e4SLinus Torvalds out_unlock: 5794a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5801da177e4SLinus Torvalds return err; 5811da177e4SLinus Torvalds } 5821da177e4SLinus Torvalds 5839903cd1cSChuck Lever /** 5849903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 5859903cd1cSChuck Lever * @task: controlling RPC task 5869903cd1cSChuck Lever * 5879903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 5889903cd1cSChuck Lever */ 5899903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 5901da177e4SLinus Torvalds { 5911da177e4SLinus Torvalds struct rpc_clnt *clnt = task->tk_client; 5921da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 5931da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 594a246b010SChuck Lever int status; 5951da177e4SLinus Torvalds 5961da177e4SLinus Torvalds dprintk("RPC: %4d xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 5971da177e4SLinus Torvalds 5981da177e4SLinus Torvalds smp_rmb(); 5991da177e4SLinus Torvalds if (!req->rq_received) { 6001da177e4SLinus Torvalds if (list_empty(&req->rq_list)) { 6014a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6021da177e4SLinus Torvalds /* Update the softirq receive buffer */ 6031da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 6041da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 6051da177e4SLinus Torvalds /* Add request to the receive list */ 6061da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 6074a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6081da177e4SLinus Torvalds xprt_reset_majortimeo(req); 6090f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 6100f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 6111da177e4SLinus Torvalds } 6121da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 6131da177e4SLinus Torvalds return; 6141da177e4SLinus Torvalds 615a246b010SChuck Lever status = xprt->ops->send_request(task); 616a246b010SChuck Lever if (!status) 6171da177e4SLinus Torvalds goto out_receive; 6181da177e4SLinus Torvalds 6191da177e4SLinus Torvalds /* Note: at this point, task->tk_sleeping has not yet been set, 6201da177e4SLinus Torvalds * hence there is no danger of the waking up task being put on 6211da177e4SLinus Torvalds * schedq, and being picked up by a parallel run of rpciod(). 6221da177e4SLinus Torvalds */ 6231da177e4SLinus Torvalds task->tk_status = status; 6241da177e4SLinus Torvalds 6251da177e4SLinus Torvalds switch (status) { 6261da177e4SLinus Torvalds case -ECONNREFUSED: 6271da177e4SLinus Torvalds task->tk_timeout = RPC_REESTABLISH_TIMEOUT; 6281da177e4SLinus Torvalds rpc_sleep_on(&xprt->sending, task, NULL, NULL); 629a246b010SChuck Lever case -EAGAIN: 6301da177e4SLinus Torvalds case -ENOTCONN: 6311da177e4SLinus Torvalds return; 6321da177e4SLinus Torvalds default: 63343118c29SChuck Lever break; 6341da177e4SLinus Torvalds } 6351da177e4SLinus Torvalds xprt_release_write(xprt, task); 6361da177e4SLinus Torvalds return; 6371da177e4SLinus Torvalds out_receive: 6381da177e4SLinus Torvalds dprintk("RPC: %4d xmit complete\n", task->tk_pid); 6391da177e4SLinus Torvalds /* Set the task's receive timeout value */ 6404a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6411da177e4SLinus Torvalds if (!xprt->nocong) { 6421da177e4SLinus Torvalds int timer = task->tk_msg.rpc_proc->p_timer; 6431da177e4SLinus Torvalds task->tk_timeout = rpc_calc_rto(clnt->cl_rtt, timer); 6441da177e4SLinus Torvalds task->tk_timeout <<= rpc_ntimeo(clnt->cl_rtt, timer) + req->rq_retries; 6451da177e4SLinus Torvalds if (task->tk_timeout > xprt->timeout.to_maxval || task->tk_timeout == 0) 6461da177e4SLinus Torvalds task->tk_timeout = xprt->timeout.to_maxval; 6471da177e4SLinus Torvalds } else 6481da177e4SLinus Torvalds task->tk_timeout = req->rq_timeout; 6491da177e4SLinus Torvalds /* Don't race with disconnect */ 6501da177e4SLinus Torvalds if (!xprt_connected(xprt)) 6511da177e4SLinus Torvalds task->tk_status = -ENOTCONN; 6521da177e4SLinus Torvalds else if (!req->rq_received) 6531da177e4SLinus Torvalds rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer); 6541da177e4SLinus Torvalds __xprt_release_write(xprt, task); 6554a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6561da177e4SLinus Torvalds } 6571da177e4SLinus Torvalds 6589903cd1cSChuck Lever static inline void do_xprt_reserve(struct rpc_task *task) 6591da177e4SLinus Torvalds { 6601da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6611da177e4SLinus Torvalds 6621da177e4SLinus Torvalds task->tk_status = 0; 6631da177e4SLinus Torvalds if (task->tk_rqstp) 6641da177e4SLinus Torvalds return; 6651da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 6661da177e4SLinus Torvalds struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 6671da177e4SLinus Torvalds list_del_init(&req->rq_list); 6681da177e4SLinus Torvalds task->tk_rqstp = req; 6691da177e4SLinus Torvalds xprt_request_init(task, xprt); 6701da177e4SLinus Torvalds return; 6711da177e4SLinus Torvalds } 6721da177e4SLinus Torvalds dprintk("RPC: waiting for request slot\n"); 6731da177e4SLinus Torvalds task->tk_status = -EAGAIN; 6741da177e4SLinus Torvalds task->tk_timeout = 0; 6751da177e4SLinus Torvalds rpc_sleep_on(&xprt->backlog, task, NULL, NULL); 6761da177e4SLinus Torvalds } 6771da177e4SLinus Torvalds 6789903cd1cSChuck Lever /** 6799903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 6809903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 6819903cd1cSChuck Lever * 6829903cd1cSChuck Lever * If no more slots are available, place the task on the transport's 6839903cd1cSChuck Lever * backlog queue. 6849903cd1cSChuck Lever */ 6859903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 6861da177e4SLinus Torvalds { 6871da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6881da177e4SLinus Torvalds 6891da177e4SLinus Torvalds task->tk_status = -EIO; 6901da177e4SLinus Torvalds if (!xprt->shutdown) { 6915dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 6921da177e4SLinus Torvalds do_xprt_reserve(task); 6935dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 6941da177e4SLinus Torvalds } 6951da177e4SLinus Torvalds } 6961da177e4SLinus Torvalds 6971da177e4SLinus Torvalds static inline u32 xprt_alloc_xid(struct rpc_xprt *xprt) 6981da177e4SLinus Torvalds { 6991da177e4SLinus Torvalds return xprt->xid++; 7001da177e4SLinus Torvalds } 7011da177e4SLinus Torvalds 7021da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 7031da177e4SLinus Torvalds { 7041da177e4SLinus Torvalds get_random_bytes(&xprt->xid, sizeof(xprt->xid)); 7051da177e4SLinus Torvalds } 7061da177e4SLinus Torvalds 7079903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 7081da177e4SLinus Torvalds { 7091da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 7101da177e4SLinus Torvalds 7111da177e4SLinus Torvalds req->rq_timeout = xprt->timeout.to_initval; 7121da177e4SLinus Torvalds req->rq_task = task; 7131da177e4SLinus Torvalds req->rq_xprt = xprt; 7141da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 7151da177e4SLinus Torvalds dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid, 7161da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 7171da177e4SLinus Torvalds } 7181da177e4SLinus Torvalds 7199903cd1cSChuck Lever /** 7209903cd1cSChuck Lever * xprt_release - release an RPC request slot 7219903cd1cSChuck Lever * @task: task which is finished with the slot 7229903cd1cSChuck Lever * 7231da177e4SLinus Torvalds */ 7249903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 7251da177e4SLinus Torvalds { 7261da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 7271da177e4SLinus Torvalds struct rpc_rqst *req; 7281da177e4SLinus Torvalds 7291da177e4SLinus Torvalds if (!(req = task->tk_rqstp)) 7301da177e4SLinus Torvalds return; 7314a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 7321da177e4SLinus Torvalds __xprt_release_write(xprt, task); 7331da177e4SLinus Torvalds __xprt_put_cong(xprt, req); 7341da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 7351da177e4SLinus Torvalds list_del(&req->rq_list); 7361da177e4SLinus Torvalds xprt->last_used = jiffies; 7371da177e4SLinus Torvalds if (list_empty(&xprt->recv) && !xprt->shutdown) 738a246b010SChuck Lever mod_timer(&xprt->timer, 739a246b010SChuck Lever xprt->last_used + RPC_IDLE_DISCONNECT_TIMEOUT); 7404a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 7411da177e4SLinus Torvalds task->tk_rqstp = NULL; 7421da177e4SLinus Torvalds memset(req, 0, sizeof(*req)); /* mark unused */ 7431da177e4SLinus Torvalds 7441da177e4SLinus Torvalds dprintk("RPC: %4d release request %p\n", task->tk_pid, req); 7451da177e4SLinus Torvalds 7465dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 7471da177e4SLinus Torvalds list_add(&req->rq_list, &xprt->free); 7481da177e4SLinus Torvalds xprt_clear_backlog(xprt); 7495dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 7501da177e4SLinus Torvalds } 7511da177e4SLinus Torvalds 7529903cd1cSChuck Lever /** 7539903cd1cSChuck Lever * xprt_set_timeout - set constant RPC timeout 7549903cd1cSChuck Lever * @to: RPC timeout parameters to set up 7559903cd1cSChuck Lever * @retr: number of retries 7569903cd1cSChuck Lever * @incr: amount of increase after each retry 7579903cd1cSChuck Lever * 7581da177e4SLinus Torvalds */ 7599903cd1cSChuck Lever void xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr) 7601da177e4SLinus Torvalds { 7611da177e4SLinus Torvalds to->to_initval = 7621da177e4SLinus Torvalds to->to_increment = incr; 763eab5c084SChuck Lever to->to_maxval = to->to_initval + (incr * retr); 7641da177e4SLinus Torvalds to->to_retries = retr; 7651da177e4SLinus Torvalds to->to_exponential = 0; 7661da177e4SLinus Torvalds } 7671da177e4SLinus Torvalds 7689903cd1cSChuck Lever static struct rpc_xprt *xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to) 7691da177e4SLinus Torvalds { 770a246b010SChuck Lever int result; 7711da177e4SLinus Torvalds struct rpc_xprt *xprt; 7721da177e4SLinus Torvalds struct rpc_rqst *req; 7731da177e4SLinus Torvalds 7741da177e4SLinus Torvalds if ((xprt = kmalloc(sizeof(struct rpc_xprt), GFP_KERNEL)) == NULL) 7751da177e4SLinus Torvalds return ERR_PTR(-ENOMEM); 7761da177e4SLinus Torvalds memset(xprt, 0, sizeof(*xprt)); /* Nnnngh! */ 7771da177e4SLinus Torvalds 7781da177e4SLinus Torvalds xprt->addr = *ap; 779a246b010SChuck Lever 780a246b010SChuck Lever switch (proto) { 781a246b010SChuck Lever case IPPROTO_UDP: 782a246b010SChuck Lever result = xs_setup_udp(xprt, to); 783a246b010SChuck Lever break; 784a246b010SChuck Lever case IPPROTO_TCP: 785a246b010SChuck Lever result = xs_setup_tcp(xprt, to); 786a246b010SChuck Lever break; 787a246b010SChuck Lever default: 788a246b010SChuck Lever printk(KERN_ERR "RPC: unrecognized transport protocol: %d\n", 789a246b010SChuck Lever proto); 790a246b010SChuck Lever result = -EIO; 791a246b010SChuck Lever break; 7921da177e4SLinus Torvalds } 793a246b010SChuck Lever if (result) { 794a246b010SChuck Lever kfree(xprt); 795a246b010SChuck Lever return ERR_PTR(result); 796a246b010SChuck Lever } 797a246b010SChuck Lever 7984a0f8c04SChuck Lever spin_lock_init(&xprt->transport_lock); 7995dc07727SChuck Lever spin_lock_init(&xprt->reserve_lock); 8001da177e4SLinus Torvalds init_waitqueue_head(&xprt->cong_wait); 8011da177e4SLinus Torvalds 8021da177e4SLinus Torvalds INIT_LIST_HEAD(&xprt->free); 8031da177e4SLinus Torvalds INIT_LIST_HEAD(&xprt->recv); 80455aa4f58SChuck Lever INIT_WORK(&xprt->task_cleanup, xprt_autoclose, xprt); 8051da177e4SLinus Torvalds init_timer(&xprt->timer); 8061da177e4SLinus Torvalds xprt->timer.function = xprt_init_autodisconnect; 8071da177e4SLinus Torvalds xprt->timer.data = (unsigned long) xprt; 8081da177e4SLinus Torvalds xprt->last_used = jiffies; 8091da177e4SLinus Torvalds 8101da177e4SLinus Torvalds rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 8111da177e4SLinus Torvalds rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 8121da177e4SLinus Torvalds rpc_init_wait_queue(&xprt->resend, "xprt_resend"); 8131da177e4SLinus Torvalds rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 8141da177e4SLinus Torvalds 8151da177e4SLinus Torvalds /* initialize free list */ 816a246b010SChuck Lever for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) 8171da177e4SLinus Torvalds list_add(&req->rq_list, &xprt->free); 8181da177e4SLinus Torvalds 8191da177e4SLinus Torvalds xprt_init_xid(xprt); 8201da177e4SLinus Torvalds 8211da177e4SLinus Torvalds dprintk("RPC: created transport %p with %u slots\n", xprt, 8221da177e4SLinus Torvalds xprt->max_reqs); 8231da177e4SLinus Torvalds 8241da177e4SLinus Torvalds return xprt; 8251da177e4SLinus Torvalds } 8261da177e4SLinus Torvalds 8279903cd1cSChuck Lever /** 8289903cd1cSChuck Lever * xprt_create_proto - create an RPC client transport 8299903cd1cSChuck Lever * @proto: requested transport protocol 8309903cd1cSChuck Lever * @sap: remote peer's address 8319903cd1cSChuck Lever * @to: timeout parameters for new transport 8329903cd1cSChuck Lever * 8331da177e4SLinus Torvalds */ 8349903cd1cSChuck Lever struct rpc_xprt *xprt_create_proto(int proto, struct sockaddr_in *sap, struct rpc_timeout *to) 8351da177e4SLinus Torvalds { 8361da177e4SLinus Torvalds struct rpc_xprt *xprt; 8371da177e4SLinus Torvalds 8381da177e4SLinus Torvalds xprt = xprt_setup(proto, sap, to); 8391da177e4SLinus Torvalds if (IS_ERR(xprt)) 8401da177e4SLinus Torvalds dprintk("RPC: xprt_create_proto failed\n"); 8411da177e4SLinus Torvalds else 8421da177e4SLinus Torvalds dprintk("RPC: xprt_create_proto created xprt %p\n", xprt); 8431da177e4SLinus Torvalds return xprt; 8441da177e4SLinus Torvalds } 8451da177e4SLinus Torvalds 8469903cd1cSChuck Lever static void xprt_shutdown(struct rpc_xprt *xprt) 8471da177e4SLinus Torvalds { 8481da177e4SLinus Torvalds xprt->shutdown = 1; 8491da177e4SLinus Torvalds rpc_wake_up(&xprt->sending); 8501da177e4SLinus Torvalds rpc_wake_up(&xprt->resend); 85144fbac22SChuck Lever xprt_wake_pending_tasks(xprt, -EIO); 8521da177e4SLinus Torvalds rpc_wake_up(&xprt->backlog); 8531da177e4SLinus Torvalds wake_up(&xprt->cong_wait); 8541da177e4SLinus Torvalds del_timer_sync(&xprt->timer); 8551da177e4SLinus Torvalds } 8561da177e4SLinus Torvalds 8579903cd1cSChuck Lever static int xprt_clear_backlog(struct rpc_xprt *xprt) { 8581da177e4SLinus Torvalds rpc_wake_up_next(&xprt->backlog); 8591da177e4SLinus Torvalds wake_up(&xprt->cong_wait); 8601da177e4SLinus Torvalds return 1; 8611da177e4SLinus Torvalds } 8621da177e4SLinus Torvalds 8639903cd1cSChuck Lever /** 8649903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 8659903cd1cSChuck Lever * @xprt: transport to destroy 8669903cd1cSChuck Lever * 8671da177e4SLinus Torvalds */ 8689903cd1cSChuck Lever int xprt_destroy(struct rpc_xprt *xprt) 8691da177e4SLinus Torvalds { 8701da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 8711da177e4SLinus Torvalds xprt_shutdown(xprt); 872a246b010SChuck Lever xprt->ops->destroy(xprt); 8731da177e4SLinus Torvalds kfree(xprt); 8741da177e4SLinus Torvalds 8751da177e4SLinus Torvalds return 0; 8761da177e4SLinus Torvalds } 877