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> 461da177e4SLinus Torvalds 47a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 4811c556b3SChuck Lever #include <linux/sunrpc/metrics.h> 491da177e4SLinus Torvalds 5055ae1aabSRicardo Labiaga #include "sunrpc.h" 5155ae1aabSRicardo Labiaga 521da177e4SLinus Torvalds /* 531da177e4SLinus Torvalds * Local variables 541da177e4SLinus Torvalds */ 551da177e4SLinus Torvalds 561da177e4SLinus Torvalds #ifdef RPC_DEBUG 571da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 581da177e4SLinus Torvalds #endif 591da177e4SLinus Torvalds 601da177e4SLinus Torvalds /* 611da177e4SLinus Torvalds * Local functions 621da177e4SLinus Torvalds */ 631da177e4SLinus Torvalds static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); 641da177e4SLinus Torvalds static inline void do_xprt_reserve(struct rpc_task *); 651da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 661da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 671da177e4SLinus Torvalds 685ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 6981c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7081c098afS\"Talpey, Thomas\ 71555ee3afSChuck Lever /* 72555ee3afSChuck Lever * The transport code maintains an estimate on the maximum number of out- 73555ee3afSChuck Lever * standing RPC requests, using a smoothed version of the congestion 74555ee3afSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 75555ee3afSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 76555ee3afSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 77555ee3afSChuck Lever * 78555ee3afSChuck Lever * - a reply is received and 79555ee3afSChuck Lever * - a full number of requests are outstanding and 80555ee3afSChuck Lever * - the congestion window hasn't been updated recently. 81555ee3afSChuck Lever */ 82555ee3afSChuck Lever #define RPC_CWNDSHIFT (8U) 83555ee3afSChuck Lever #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 84555ee3afSChuck Lever #define RPC_INITCWND RPC_CWNDSCALE 85555ee3afSChuck Lever #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 86555ee3afSChuck Lever 87555ee3afSChuck Lever #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 881da177e4SLinus Torvalds 8912a80469SChuck Lever /** 9081c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 9181c098afS\"Talpey, Thomas\ * @transport: transport to register 9281c098afS\"Talpey, Thomas\ * 9381c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 9481c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 9581c098afS\"Talpey, Thomas\ * 9681c098afS\"Talpey, Thomas\ * Returns: 9781c098afS\"Talpey, Thomas\ * 0: transport successfully registered 9881c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 9981c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 10081c098afS\"Talpey, Thomas\ */ 10181c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 10281c098afS\"Talpey, Thomas\ { 10381c098afS\"Talpey, Thomas\ struct xprt_class *t; 10481c098afS\"Talpey, Thomas\ int result; 10581c098afS\"Talpey, Thomas\ 10681c098afS\"Talpey, Thomas\ result = -EEXIST; 10781c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 10881c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 10981c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 1104fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 11181c098afS\"Talpey, Thomas\ goto out; 11281c098afS\"Talpey, Thomas\ } 11381c098afS\"Talpey, Thomas\ 11481c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 11581c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 11681c098afS\"Talpey, Thomas\ transport->name); 11781c098afS\"Talpey, Thomas\ result = 0; 11881c098afS\"Talpey, Thomas\ 11981c098afS\"Talpey, Thomas\ out: 12081c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 12181c098afS\"Talpey, Thomas\ return result; 12281c098afS\"Talpey, Thomas\ } 12381c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 12481c098afS\"Talpey, Thomas\ 12581c098afS\"Talpey, Thomas\ /** 12681c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 12765b6e42cSRandy Dunlap * @transport: transport to unregister 12881c098afS\"Talpey, Thomas\ * 12981c098afS\"Talpey, Thomas\ * Returns: 13081c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 13181c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 13281c098afS\"Talpey, Thomas\ */ 13381c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 13481c098afS\"Talpey, Thomas\ { 13581c098afS\"Talpey, Thomas\ struct xprt_class *t; 13681c098afS\"Talpey, Thomas\ int result; 13781c098afS\"Talpey, Thomas\ 13881c098afS\"Talpey, Thomas\ result = 0; 13981c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 14081c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 14181c098afS\"Talpey, Thomas\ if (t == transport) { 14281c098afS\"Talpey, Thomas\ printk(KERN_INFO 14381c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 14481c098afS\"Talpey, Thomas\ transport->name); 14581c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 14681c098afS\"Talpey, Thomas\ goto out; 14781c098afS\"Talpey, Thomas\ } 14881c098afS\"Talpey, Thomas\ } 14981c098afS\"Talpey, Thomas\ result = -ENOENT; 15081c098afS\"Talpey, Thomas\ 15181c098afS\"Talpey, Thomas\ out: 15281c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 15381c098afS\"Talpey, Thomas\ return result; 15481c098afS\"Talpey, Thomas\ } 15581c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 15681c098afS\"Talpey, Thomas\ 15781c098afS\"Talpey, Thomas\ /** 158441e3e24STom Talpey * xprt_load_transport - load a transport implementation 159441e3e24STom Talpey * @transport_name: transport to load 160441e3e24STom Talpey * 161441e3e24STom Talpey * Returns: 162441e3e24STom Talpey * 0: transport successfully loaded 163441e3e24STom Talpey * -ENOENT: transport module not available 164441e3e24STom Talpey */ 165441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 166441e3e24STom Talpey { 167441e3e24STom Talpey struct xprt_class *t; 168441e3e24STom Talpey char module_name[sizeof t->name + 5]; 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); 180441e3e24STom Talpey strcpy(module_name, "xprt"); 181441e3e24STom Talpey strncat(module_name, transport_name, sizeof t->name); 182441e3e24STom Talpey result = request_module(module_name); 183441e3e24STom Talpey out: 184441e3e24STom Talpey return result; 185441e3e24STom Talpey } 186441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 187441e3e24STom Talpey 188441e3e24STom Talpey /** 18912a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 19012a80469SChuck Lever * @task: task that is requesting access to the transport 19112a80469SChuck Lever * 19212a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 19312a80469SChuck Lever * transport connects from colliding with writes. No congestion control 19412a80469SChuck Lever * is provided. 1951da177e4SLinus Torvalds */ 19612a80469SChuck Lever int xprt_reserve_xprt(struct rpc_task *task) 1971da177e4SLinus Torvalds { 19812a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 199343952faSRahul Iyer struct rpc_xprt *xprt = req->rq_xprt; 20012a80469SChuck Lever 20112a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 20212a80469SChuck Lever if (task == xprt->snd_task) 20312a80469SChuck Lever return 1; 20412a80469SChuck Lever if (task == NULL) 20512a80469SChuck Lever return 0; 20612a80469SChuck Lever goto out_sleep; 20712a80469SChuck Lever } 20812a80469SChuck Lever xprt->snd_task = task; 20912a80469SChuck Lever if (req) { 21012a80469SChuck Lever req->rq_bytes_sent = 0; 21112a80469SChuck Lever req->rq_ntrans++; 21212a80469SChuck Lever } 21312a80469SChuck Lever return 1; 21412a80469SChuck Lever 21512a80469SChuck Lever out_sleep: 21646121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", 21712a80469SChuck Lever task->tk_pid, xprt); 21812a80469SChuck Lever task->tk_timeout = 0; 21912a80469SChuck Lever task->tk_status = -EAGAIN; 22012a80469SChuck Lever if (req && req->rq_ntrans) 2215d00837bSTrond Myklebust rpc_sleep_on(&xprt->resend, task, NULL); 22212a80469SChuck Lever else 2235d00837bSTrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 22412a80469SChuck Lever return 0; 22512a80469SChuck Lever } 22612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 22712a80469SChuck Lever 228632e3bdcSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 229632e3bdcSTrond Myklebust { 230632e3bdcSTrond Myklebust xprt->snd_task = NULL; 231632e3bdcSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { 232632e3bdcSTrond Myklebust smp_mb__before_clear_bit(); 233632e3bdcSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 234632e3bdcSTrond Myklebust smp_mb__after_clear_bit(); 235632e3bdcSTrond Myklebust } else 236c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 237632e3bdcSTrond Myklebust } 238632e3bdcSTrond Myklebust 23912a80469SChuck Lever /* 24012a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 24112a80469SChuck Lever * @task: task that is requesting access to the transport 24212a80469SChuck Lever * 24312a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 24412a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 24512a80469SChuck Lever * woken up and given access to the transport. 24612a80469SChuck Lever */ 24712a80469SChuck Lever int xprt_reserve_xprt_cong(struct rpc_task *task) 24812a80469SChuck Lever { 24912a80469SChuck Lever struct rpc_xprt *xprt = task->tk_xprt; 2501da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 2511da177e4SLinus Torvalds 2522226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2531da177e4SLinus Torvalds if (task == xprt->snd_task) 2541da177e4SLinus Torvalds return 1; 2551da177e4SLinus Torvalds goto out_sleep; 2561da177e4SLinus Torvalds } 25712a80469SChuck Lever if (__xprt_get_cong(xprt, task)) { 2581da177e4SLinus Torvalds xprt->snd_task = task; 2591da177e4SLinus Torvalds if (req) { 2601da177e4SLinus Torvalds req->rq_bytes_sent = 0; 2611da177e4SLinus Torvalds req->rq_ntrans++; 2621da177e4SLinus Torvalds } 2631da177e4SLinus Torvalds return 1; 2641da177e4SLinus Torvalds } 265632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2661da177e4SLinus Torvalds out_sleep: 26746121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 2681da177e4SLinus Torvalds task->tk_timeout = 0; 2691da177e4SLinus Torvalds task->tk_status = -EAGAIN; 2701da177e4SLinus Torvalds if (req && req->rq_ntrans) 2715d00837bSTrond Myklebust rpc_sleep_on(&xprt->resend, task, NULL); 2721da177e4SLinus Torvalds else 2735d00837bSTrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 2741da177e4SLinus Torvalds return 0; 2751da177e4SLinus Torvalds } 27612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2771da177e4SLinus Torvalds 27812a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2791da177e4SLinus Torvalds { 2801da177e4SLinus Torvalds int retval; 2811da177e4SLinus Torvalds 2824a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 28312a80469SChuck Lever retval = xprt->ops->reserve_xprt(task); 2844a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2851da177e4SLinus Torvalds return retval; 2861da177e4SLinus Torvalds } 2871da177e4SLinus Torvalds 28812a80469SChuck Lever static void __xprt_lock_write_next(struct rpc_xprt *xprt) 2891da177e4SLinus Torvalds { 2901da177e4SLinus Torvalds struct rpc_task *task; 29149e9a890SChuck Lever struct rpc_rqst *req; 29249e9a890SChuck Lever 29349e9a890SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 29449e9a890SChuck Lever return; 29549e9a890SChuck Lever 29649e9a890SChuck Lever task = rpc_wake_up_next(&xprt->resend); 29749e9a890SChuck Lever if (!task) { 29849e9a890SChuck Lever task = rpc_wake_up_next(&xprt->sending); 29949e9a890SChuck Lever if (!task) 30049e9a890SChuck Lever goto out_unlock; 30149e9a890SChuck Lever } 30249e9a890SChuck Lever 30349e9a890SChuck Lever req = task->tk_rqstp; 30449e9a890SChuck Lever xprt->snd_task = task; 30549e9a890SChuck Lever if (req) { 30649e9a890SChuck Lever req->rq_bytes_sent = 0; 30749e9a890SChuck Lever req->rq_ntrans++; 30849e9a890SChuck Lever } 30949e9a890SChuck Lever return; 31049e9a890SChuck Lever 31149e9a890SChuck Lever out_unlock: 312632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 31349e9a890SChuck Lever } 31449e9a890SChuck Lever 31549e9a890SChuck Lever static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 31649e9a890SChuck Lever { 31749e9a890SChuck Lever struct rpc_task *task; 3181da177e4SLinus Torvalds 3192226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 3201da177e4SLinus Torvalds return; 32149e9a890SChuck Lever if (RPCXPRT_CONGESTED(xprt)) 3221da177e4SLinus Torvalds goto out_unlock; 3231da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->resend); 3241da177e4SLinus Torvalds if (!task) { 3251da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->sending); 3261da177e4SLinus Torvalds if (!task) 3271da177e4SLinus Torvalds goto out_unlock; 3281da177e4SLinus Torvalds } 32949e9a890SChuck Lever if (__xprt_get_cong(xprt, task)) { 3301da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3311da177e4SLinus Torvalds xprt->snd_task = task; 3321da177e4SLinus Torvalds if (req) { 3331da177e4SLinus Torvalds req->rq_bytes_sent = 0; 3341da177e4SLinus Torvalds req->rq_ntrans++; 3351da177e4SLinus Torvalds } 3361da177e4SLinus Torvalds return; 3371da177e4SLinus Torvalds } 3381da177e4SLinus Torvalds out_unlock: 339632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3401da177e4SLinus Torvalds } 3411da177e4SLinus Torvalds 34249e9a890SChuck Lever /** 34349e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 34449e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 34549e9a890SChuck Lever * @task: task that is releasing access to the transport 34649e9a890SChuck Lever * 34749e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 3481da177e4SLinus Torvalds */ 34949e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3501da177e4SLinus Torvalds { 3511da177e4SLinus Torvalds if (xprt->snd_task == task) { 352632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3531da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3541da177e4SLinus Torvalds } 3551da177e4SLinus Torvalds } 35612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3571da177e4SLinus Torvalds 35849e9a890SChuck Lever /** 35949e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 36049e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 36149e9a890SChuck Lever * @task: task that is releasing access to the transport 36249e9a890SChuck Lever * 36349e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 36449e9a890SChuck Lever * transport if the transport's congestion window allows it. 36549e9a890SChuck Lever */ 36649e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 36749e9a890SChuck Lever { 36849e9a890SChuck Lever if (xprt->snd_task == task) { 369632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 37049e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 37149e9a890SChuck Lever } 37249e9a890SChuck Lever } 37312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 37449e9a890SChuck Lever 37549e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3761da177e4SLinus Torvalds { 3774a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 37849e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3794a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3801da177e4SLinus Torvalds } 3811da177e4SLinus Torvalds 3821da177e4SLinus Torvalds /* 3831da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3841da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3851da177e4SLinus Torvalds */ 3861da177e4SLinus Torvalds static int 3871da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 3881da177e4SLinus Torvalds { 3891da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3901da177e4SLinus Torvalds 3911da177e4SLinus Torvalds if (req->rq_cong) 3921da177e4SLinus Torvalds return 1; 39346121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 3941da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 3951da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 3961da177e4SLinus Torvalds return 0; 3971da177e4SLinus Torvalds req->rq_cong = 1; 3981da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 3991da177e4SLinus Torvalds return 1; 4001da177e4SLinus Torvalds } 4011da177e4SLinus Torvalds 4021da177e4SLinus Torvalds /* 4031da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4041da177e4SLinus Torvalds * that has been sleeping due to congestion 4051da177e4SLinus Torvalds */ 4061da177e4SLinus Torvalds static void 4071da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4081da177e4SLinus Torvalds { 4091da177e4SLinus Torvalds if (!req->rq_cong) 4101da177e4SLinus Torvalds return; 4111da177e4SLinus Torvalds req->rq_cong = 0; 4121da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 41349e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4141da177e4SLinus Torvalds } 4151da177e4SLinus Torvalds 41646c0ee8bSChuck Lever /** 417a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 418a58dd398SChuck Lever * @task: RPC request that recently completed 419a58dd398SChuck Lever * 420a58dd398SChuck Lever * Useful for transports that require congestion control. 421a58dd398SChuck Lever */ 422a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 423a58dd398SChuck Lever { 424a58dd398SChuck Lever __xprt_put_cong(task->tk_xprt, task->tk_rqstp); 425a58dd398SChuck Lever } 42612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 427a58dd398SChuck Lever 428a58dd398SChuck Lever /** 42946c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 43046c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 43146c0ee8bSChuck Lever * @result: result code of completed RPC request 43246c0ee8bSChuck Lever * 4331da177e4SLinus Torvalds * We use a time-smoothed congestion estimator to avoid heavy oscillation. 4341da177e4SLinus Torvalds */ 43546c0ee8bSChuck Lever void xprt_adjust_cwnd(struct rpc_task *task, int result) 4361da177e4SLinus Torvalds { 43746c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 43846c0ee8bSChuck Lever struct rpc_xprt *xprt = task->tk_xprt; 43946c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4401da177e4SLinus Torvalds 4411da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4421da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4431da177e4SLinus Torvalds * the result gets rounded properly. */ 4441da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4451da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4461da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 44749e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4481da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4491da177e4SLinus Torvalds cwnd >>= 1; 4501da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4511da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4521da177e4SLinus Torvalds } 4531da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4541da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4551da177e4SLinus Torvalds xprt->cwnd = cwnd; 45646c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4571da177e4SLinus Torvalds } 45812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4591da177e4SLinus Torvalds 46044fbac22SChuck Lever /** 46144fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 46244fbac22SChuck Lever * @xprt: transport with waiting tasks 46344fbac22SChuck Lever * @status: result code to plant in each task before waking it 46444fbac22SChuck Lever * 46544fbac22SChuck Lever */ 46644fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 46744fbac22SChuck Lever { 46844fbac22SChuck Lever if (status < 0) 46944fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 47044fbac22SChuck Lever else 47144fbac22SChuck Lever rpc_wake_up(&xprt->pending); 47244fbac22SChuck Lever } 47312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 47444fbac22SChuck Lever 475c7b2cae8SChuck Lever /** 476c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 477c7b2cae8SChuck Lever * @task: task to be put to sleep 4780b80ae42SRandy Dunlap * @action: function pointer to be executed after wait 479c7b2cae8SChuck Lever */ 480b6ddf64fSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) 481c7b2cae8SChuck Lever { 482c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 483c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 484c7b2cae8SChuck Lever 485c7b2cae8SChuck Lever task->tk_timeout = req->rq_timeout; 486b6ddf64fSTrond Myklebust rpc_sleep_on(&xprt->pending, task, action); 487c7b2cae8SChuck Lever } 48812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 489c7b2cae8SChuck Lever 490c7b2cae8SChuck Lever /** 491c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 492c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 493c7b2cae8SChuck Lever * 494c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 495c7b2cae8SChuck Lever */ 496c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 497c7b2cae8SChuck Lever { 498c7b2cae8SChuck Lever if (unlikely(xprt->shutdown)) 499c7b2cae8SChuck Lever return; 500c7b2cae8SChuck Lever 501c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 502c7b2cae8SChuck Lever if (xprt->snd_task) { 50346121cf7SChuck Lever dprintk("RPC: write space: waking waiting task on " 50446121cf7SChuck Lever "xprt %p\n", xprt); 505fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); 506c7b2cae8SChuck Lever } 507c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 508c7b2cae8SChuck Lever } 50912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 510c7b2cae8SChuck Lever 511fe3aca29SChuck Lever /** 512fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 513fe3aca29SChuck Lever * @task: task whose timeout is to be set 514fe3aca29SChuck Lever * 515fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 516fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 517fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 518fe3aca29SChuck Lever */ 519fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 520fe3aca29SChuck Lever { 521fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 522fe3aca29SChuck Lever } 52312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 524fe3aca29SChuck Lever 525fe3aca29SChuck Lever /* 526fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout 527fe3aca29SChuck Lever * @task: task whose timeout is to be set 528fe3aca29SChuck Lever * 529fe3aca29SChuck Lever * Set a request's retransmit timeout using the RTT estimator. 530fe3aca29SChuck Lever */ 531fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 532fe3aca29SChuck Lever { 533fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 534ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 535ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 536fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 537ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 538fe3aca29SChuck Lever 539fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 540fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 541fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 542fe3aca29SChuck Lever task->tk_timeout = max_timeout; 543fe3aca29SChuck Lever } 54412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 545fe3aca29SChuck Lever 5461da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5471da177e4SLinus Torvalds { 548ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5491da177e4SLinus Torvalds 5501da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5511da177e4SLinus Torvalds if (to->to_exponential) 5521da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5531da177e4SLinus Torvalds else 5541da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 5551da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 5561da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 5571da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 5581da177e4SLinus Torvalds } 5591da177e4SLinus Torvalds 5609903cd1cSChuck Lever /** 5619903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 5629903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 5639903cd1cSChuck Lever * 5641da177e4SLinus Torvalds */ 5651da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 5661da177e4SLinus Torvalds { 5671da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 568ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5691da177e4SLinus Torvalds int status = 0; 5701da177e4SLinus Torvalds 5711da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 5721da177e4SLinus Torvalds if (to->to_exponential) 5731da177e4SLinus Torvalds req->rq_timeout <<= 1; 5741da177e4SLinus Torvalds else 5751da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 5761da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 5771da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 5781da177e4SLinus Torvalds req->rq_retries++; 5791da177e4SLinus Torvalds } else { 5801da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 5811da177e4SLinus Torvalds req->rq_retries = 0; 5821da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5831da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 5844a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5851da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 5864a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5871da177e4SLinus Torvalds status = -ETIMEDOUT; 5881da177e4SLinus Torvalds } 5891da177e4SLinus Torvalds 5901da177e4SLinus Torvalds if (req->rq_timeout == 0) { 5911da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 5921da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 5931da177e4SLinus Torvalds } 5941da177e4SLinus Torvalds return status; 5951da177e4SLinus Torvalds } 5961da177e4SLinus Torvalds 59765f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 5981da177e4SLinus Torvalds { 59965f27f38SDavid Howells struct rpc_xprt *xprt = 60065f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 6011da177e4SLinus Torvalds 602a246b010SChuck Lever xprt->ops->close(xprt); 60366af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 6041da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 6051da177e4SLinus Torvalds } 6061da177e4SLinus Torvalds 6079903cd1cSChuck Lever /** 60862da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6099903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6109903cd1cSChuck Lever * 6111da177e4SLinus Torvalds */ 61262da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6131da177e4SLinus Torvalds { 6141da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6154a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6161da177e4SLinus Torvalds xprt_clear_connected(xprt); 6172a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6184a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6191da177e4SLinus Torvalds } 62062da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6211da177e4SLinus Torvalds 62266af1e55STrond Myklebust /** 62366af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 62466af1e55STrond Myklebust * @xprt: transport to disconnect 62566af1e55STrond Myklebust * 62666af1e55STrond Myklebust */ 62766af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 62866af1e55STrond Myklebust { 62966af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 63066af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 63166af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 63266af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 63366af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 63466af1e55STrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6352a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 63666af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 63766af1e55STrond Myklebust } 63866af1e55STrond Myklebust 6397c1d71cfSTrond Myklebust /** 6407c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 6417c1d71cfSTrond Myklebust * @xprt: transport to disconnect 6427c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 6437c1d71cfSTrond Myklebust * 6447c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 6457c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 6467c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 6477c1d71cfSTrond Myklebust * a batch of RPC requests. 6487c1d71cfSTrond Myklebust * 6497c1d71cfSTrond Myklebust */ 6507c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 6517c1d71cfSTrond Myklebust { 6527c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 6537c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 6547c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 6557c1d71cfSTrond Myklebust goto out; 6567c1d71cfSTrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) 6577c1d71cfSTrond Myklebust goto out; 6587c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 6597c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 6607c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 6617c1d71cfSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6622a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6637c1d71cfSTrond Myklebust out: 6647c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 6657c1d71cfSTrond Myklebust } 6667c1d71cfSTrond Myklebust 6671da177e4SLinus Torvalds static void 6681da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 6691da177e4SLinus Torvalds { 6701da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 6711da177e4SLinus Torvalds 6724a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 6731da177e4SLinus Torvalds if (!list_empty(&xprt->recv) || xprt->shutdown) 6741da177e4SLinus Torvalds goto out_abort; 6752226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 6761da177e4SLinus Torvalds goto out_abort; 6774a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 678f75e6745STrond Myklebust set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); 679c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6801da177e4SLinus Torvalds return; 6811da177e4SLinus Torvalds out_abort: 6824a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 6831da177e4SLinus Torvalds } 6841da177e4SLinus Torvalds 6859903cd1cSChuck Lever /** 6869903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 6879903cd1cSChuck Lever * @task: RPC task that is requesting the connect 6881da177e4SLinus Torvalds * 6891da177e4SLinus Torvalds */ 6901da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 6911da177e4SLinus Torvalds { 6921da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6931da177e4SLinus Torvalds 69446121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 6951da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 6961da177e4SLinus Torvalds 697ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 69801d37c42STrond Myklebust task->tk_status = -EAGAIN; 6991da177e4SLinus Torvalds return; 7001da177e4SLinus Torvalds } 7011da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 7021da177e4SLinus Torvalds return; 7031da177e4SLinus Torvalds if (xprt_connected(xprt)) 704a246b010SChuck Lever xprt_release_write(xprt, task); 705a246b010SChuck Lever else { 7061da177e4SLinus Torvalds if (task->tk_rqstp) 7071da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 7081da177e4SLinus Torvalds 70903bf4b70SChuck Lever task->tk_timeout = xprt->connect_timeout; 7105d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_connect_status); 711262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 712a246b010SChuck Lever xprt->ops->connect(task); 7131da177e4SLinus Torvalds } 7141da177e4SLinus Torvalds return; 7151da177e4SLinus Torvalds } 7161da177e4SLinus Torvalds 7179903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 7181da177e4SLinus Torvalds { 7191da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 7201da177e4SLinus Torvalds 721cd983ef8SChuck Lever if (task->tk_status == 0) { 722262ca07dSChuck Lever xprt->stat.connect_count++; 723262ca07dSChuck Lever xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; 72446121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connection established\n", 7251da177e4SLinus Torvalds task->tk_pid); 7261da177e4SLinus Torvalds return; 7271da177e4SLinus Torvalds } 7281da177e4SLinus Torvalds 7291da177e4SLinus Torvalds switch (task->tk_status) { 7302a491991STrond Myklebust case -EAGAIN: 7312a491991STrond Myklebust dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); 73223475d66SChuck Lever break; 7331da177e4SLinus Torvalds case -ETIMEDOUT: 73446121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connect attempt timed " 73546121cf7SChuck Lever "out\n", task->tk_pid); 7361da177e4SLinus Torvalds break; 7371da177e4SLinus Torvalds default: 73846121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: error %d connecting to " 73946121cf7SChuck Lever "server %s\n", task->tk_pid, -task->tk_status, 74046121cf7SChuck Lever task->tk_client->cl_server); 7411da177e4SLinus Torvalds xprt_release_write(xprt, task); 74223475d66SChuck Lever task->tk_status = -EIO; 74323475d66SChuck Lever } 7441da177e4SLinus Torvalds } 7451da177e4SLinus Torvalds 7469903cd1cSChuck Lever /** 7479903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 7489903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 7499903cd1cSChuck Lever * @xid: RPC XID of incoming reply 7509903cd1cSChuck Lever * 7511da177e4SLinus Torvalds */ 752d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 7531da177e4SLinus Torvalds { 7541da177e4SLinus Torvalds struct list_head *pos; 7551da177e4SLinus Torvalds 7561da177e4SLinus Torvalds list_for_each(pos, &xprt->recv) { 7571da177e4SLinus Torvalds struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); 758262ca07dSChuck Lever if (entry->rq_xid == xid) 759262ca07dSChuck Lever return entry; 7601da177e4SLinus Torvalds } 76146121cf7SChuck Lever 76246121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 76346121cf7SChuck Lever ntohl(xid)); 764262ca07dSChuck Lever xprt->stat.bad_xids++; 765262ca07dSChuck Lever return NULL; 7661da177e4SLinus Torvalds } 76712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 7681da177e4SLinus Torvalds 7699903cd1cSChuck Lever /** 7701570c1e4SChuck Lever * xprt_update_rtt - update an RPC client's RTT state after receiving a reply 7711570c1e4SChuck Lever * @task: RPC request that recently completed 7729903cd1cSChuck Lever * 7731da177e4SLinus Torvalds */ 7741570c1e4SChuck Lever void xprt_update_rtt(struct rpc_task *task) 7751da177e4SLinus Torvalds { 7761570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 7771570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 7781da177e4SLinus Torvalds unsigned timer = task->tk_msg.rpc_proc->p_timer; 7791570c1e4SChuck Lever 7801da177e4SLinus Torvalds if (timer) { 7811da177e4SLinus Torvalds if (req->rq_ntrans == 1) 7821570c1e4SChuck Lever rpc_update_rtt(rtt, timer, 7831da177e4SLinus Torvalds (long)jiffies - req->rq_xtime); 7841570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 7851da177e4SLinus Torvalds } 7861da177e4SLinus Torvalds } 78712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_update_rtt); 7881da177e4SLinus Torvalds 7891570c1e4SChuck Lever /** 7901570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 7911570c1e4SChuck Lever * @task: RPC request that recently completed 7921570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 7931570c1e4SChuck Lever * 7941570c1e4SChuck Lever * Caller holds transport lock. 7951570c1e4SChuck Lever */ 7961570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 7971570c1e4SChuck Lever { 7981570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 799fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 8001da177e4SLinus Torvalds 8011570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 8021570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 8031da177e4SLinus Torvalds 804fda13939STrond Myklebust xprt->stat.recvs++; 805ef759a2eSChuck Lever task->tk_rtt = (long)jiffies - req->rq_xtime; 806ef759a2eSChuck Lever 8071da177e4SLinus Torvalds list_del_init(&req->rq_list); 8081e799b67STrond Myklebust req->rq_private_buf.len = copied; 80943ac3f29STrond Myklebust /* Ensure all writes are done before we update req->rq_received */ 81043ac3f29STrond Myklebust smp_wmb(); 8111e799b67STrond Myklebust req->rq_received = copied; 812fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 8131da177e4SLinus Torvalds } 81412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 8151da177e4SLinus Torvalds 81646c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 8171da177e4SLinus Torvalds { 8181da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8191da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8201da177e4SLinus Torvalds 8215d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 8225d00837bSTrond Myklebust return; 82346121cf7SChuck Lever dprintk("RPC: %5u xprt_timer\n", task->tk_pid); 82446c0ee8bSChuck Lever 8255d00837bSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 82646c0ee8bSChuck Lever if (!req->rq_received) { 82746c0ee8bSChuck Lever if (xprt->ops->timer) 82846c0ee8bSChuck Lever xprt->ops->timer(task); 8295d00837bSTrond Myklebust } else 8305d00837bSTrond Myklebust task->tk_status = 0; 8315d00837bSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 8321da177e4SLinus Torvalds } 8331da177e4SLinus Torvalds 8349903cd1cSChuck Lever /** 8359903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 8369903cd1cSChuck Lever * @task: RPC task about to send a request 8379903cd1cSChuck Lever * 8381da177e4SLinus Torvalds */ 8399903cd1cSChuck Lever int xprt_prepare_transmit(struct rpc_task *task) 8401da177e4SLinus Torvalds { 8411da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8421da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8431da177e4SLinus Torvalds int err = 0; 8441da177e4SLinus Torvalds 84546121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 8461da177e4SLinus Torvalds 8474a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 8481da177e4SLinus Torvalds if (req->rq_received && !req->rq_bytes_sent) { 8491da177e4SLinus Torvalds err = req->rq_received; 8501da177e4SLinus Torvalds goto out_unlock; 8511da177e4SLinus Torvalds } 8522a491991STrond Myklebust if (!xprt->ops->reserve_xprt(task)) 8531da177e4SLinus Torvalds err = -EAGAIN; 8541da177e4SLinus Torvalds out_unlock: 8554a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 8561da177e4SLinus Torvalds return err; 8571da177e4SLinus Torvalds } 8581da177e4SLinus Torvalds 859e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 8605e5ce5beSTrond Myklebust { 861343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 8625e5ce5beSTrond Myklebust } 8635e5ce5beSTrond Myklebust 8649903cd1cSChuck Lever /** 8659903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 8669903cd1cSChuck Lever * @task: controlling RPC task 8679903cd1cSChuck Lever * 8689903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 8699903cd1cSChuck Lever */ 8709903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 8711da177e4SLinus Torvalds { 8721da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8731da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 874a246b010SChuck Lever int status; 8751da177e4SLinus Torvalds 87646121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 8771da177e4SLinus Torvalds 8781da177e4SLinus Torvalds if (!req->rq_received) { 87955ae1aabSRicardo Labiaga if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { 88055ae1aabSRicardo Labiaga /* 88155ae1aabSRicardo Labiaga * Add to the list only if we're expecting a reply 88255ae1aabSRicardo Labiaga */ 8834a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 8841da177e4SLinus Torvalds /* Update the softirq receive buffer */ 8851da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 8861da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 8871da177e4SLinus Torvalds /* Add request to the receive list */ 8881da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 8894a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 8901da177e4SLinus Torvalds xprt_reset_majortimeo(req); 8910f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 8920f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 8931da177e4SLinus Torvalds } 8941da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 8951da177e4SLinus Torvalds return; 8961da177e4SLinus Torvalds 8977c1d71cfSTrond Myklebust req->rq_connect_cookie = xprt->connect_cookie; 898b22602a6SChuck Lever req->rq_xtime = jiffies; 899a246b010SChuck Lever status = xprt->ops->send_request(task); 900c8485e4dSTrond Myklebust if (status != 0) { 901c8485e4dSTrond Myklebust task->tk_status = status; 902c8485e4dSTrond Myklebust return; 903c8485e4dSTrond Myklebust } 904c8485e4dSTrond Myklebust 90546121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 906fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 907262ca07dSChuck Lever 908fe3aca29SChuck Lever xprt->ops->set_retrans_timeout(task); 909262ca07dSChuck Lever 910262ca07dSChuck Lever xprt->stat.sends++; 911262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 912262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 913262ca07dSChuck Lever 914fe3aca29SChuck Lever /* Don't race with disconnect */ 915fe3aca29SChuck Lever if (!xprt_connected(xprt)) 916fe3aca29SChuck Lever task->tk_status = -ENOTCONN; 91755ae1aabSRicardo Labiaga else if (!req->rq_received && rpc_reply_expected(task)) { 91855ae1aabSRicardo Labiaga /* 91955ae1aabSRicardo Labiaga * Sleep on the pending queue since 92055ae1aabSRicardo Labiaga * we're expecting a reply. 92155ae1aabSRicardo Labiaga */ 9225d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 92355ae1aabSRicardo Labiaga } 924fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9251da177e4SLinus Torvalds } 9261da177e4SLinus Torvalds 9279903cd1cSChuck Lever static inline void do_xprt_reserve(struct rpc_task *task) 9281da177e4SLinus Torvalds { 9291da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 9301da177e4SLinus Torvalds 9311da177e4SLinus Torvalds task->tk_status = 0; 9321da177e4SLinus Torvalds if (task->tk_rqstp) 9331da177e4SLinus Torvalds return; 9341da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 9351da177e4SLinus Torvalds struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 9361da177e4SLinus Torvalds list_del_init(&req->rq_list); 9371da177e4SLinus Torvalds task->tk_rqstp = req; 9381da177e4SLinus Torvalds xprt_request_init(task, xprt); 9391da177e4SLinus Torvalds return; 9401da177e4SLinus Torvalds } 9411da177e4SLinus Torvalds dprintk("RPC: waiting for request slot\n"); 9421da177e4SLinus Torvalds task->tk_status = -EAGAIN; 9431da177e4SLinus Torvalds task->tk_timeout = 0; 9445d00837bSTrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 9451da177e4SLinus Torvalds } 9461da177e4SLinus Torvalds 9479903cd1cSChuck Lever /** 9489903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 9499903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 9509903cd1cSChuck Lever * 9519903cd1cSChuck Lever * If no more slots are available, place the task on the transport's 9529903cd1cSChuck Lever * backlog queue. 9539903cd1cSChuck Lever */ 9549903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 9551da177e4SLinus Torvalds { 9561da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 9571da177e4SLinus Torvalds 9581da177e4SLinus Torvalds task->tk_status = -EIO; 9595dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 9601da177e4SLinus Torvalds do_xprt_reserve(task); 9615dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 9621da177e4SLinus Torvalds } 9631da177e4SLinus Torvalds 964d8ed029dSAlexey Dobriyan static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) 9651da177e4SLinus Torvalds { 9661da177e4SLinus Torvalds return xprt->xid++; 9671da177e4SLinus Torvalds } 9681da177e4SLinus Torvalds 9691da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 9701da177e4SLinus Torvalds { 971bf3fcf89SChuck Lever xprt->xid = net_random(); 9721da177e4SLinus Torvalds } 9731da177e4SLinus Torvalds 9749903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 9751da177e4SLinus Torvalds { 9761da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 9771da177e4SLinus Torvalds 978ba7392bbSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 9791da177e4SLinus Torvalds req->rq_task = task; 9801da177e4SLinus Torvalds req->rq_xprt = xprt; 98102107148SChuck Lever req->rq_buffer = NULL; 9821da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 983ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf = NULL; 984da45828eSTrond Myklebust xprt_reset_majortimeo(req); 98546121cf7SChuck Lever dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 9861da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 9871da177e4SLinus Torvalds } 9881da177e4SLinus Torvalds 9899903cd1cSChuck Lever /** 9909903cd1cSChuck Lever * xprt_release - release an RPC request slot 9919903cd1cSChuck Lever * @task: task which is finished with the slot 9929903cd1cSChuck Lever * 9931da177e4SLinus Torvalds */ 9949903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 9951da177e4SLinus Torvalds { 99655ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 9971da177e4SLinus Torvalds struct rpc_rqst *req; 99855ae1aabSRicardo Labiaga int is_bc_request; 9991da177e4SLinus Torvalds 10001da177e4SLinus Torvalds if (!(req = task->tk_rqstp)) 10011da177e4SLinus Torvalds return; 100255ae1aabSRicardo Labiaga 100355ae1aabSRicardo Labiaga /* Preallocated backchannel request? */ 100455ae1aabSRicardo Labiaga is_bc_request = bc_prealloc(req); 100555ae1aabSRicardo Labiaga 100655ae1aabSRicardo Labiaga xprt = req->rq_xprt; 100711c556b3SChuck Lever rpc_count_iostats(task); 10084a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 100949e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1010a58dd398SChuck Lever if (xprt->ops->release_request) 1011a58dd398SChuck Lever xprt->ops->release_request(task); 10121da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 10131da177e4SLinus Torvalds list_del(&req->rq_list); 10141da177e4SLinus Torvalds xprt->last_used = jiffies; 10150065db32STrond Myklebust if (list_empty(&xprt->recv)) 1016a246b010SChuck Lever mod_timer(&xprt->timer, 101703bf4b70SChuck Lever xprt->last_used + xprt->idle_timeout); 10184a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 101955ae1aabSRicardo Labiaga if (!bc_prealloc(req)) 1020c5a4dd8bSChuck Lever xprt->ops->buf_free(req->rq_buffer); 10211da177e4SLinus Torvalds task->tk_rqstp = NULL; 1022ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1023ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 102455ae1aabSRicardo Labiaga 102555ae1aabSRicardo Labiaga /* 102655ae1aabSRicardo Labiaga * Early exit if this is a backchannel preallocated request. 102755ae1aabSRicardo Labiaga * There is no need to have it added to the RPC slot list. 102855ae1aabSRicardo Labiaga */ 102955ae1aabSRicardo Labiaga if (is_bc_request) 103055ae1aabSRicardo Labiaga return; 103155ae1aabSRicardo Labiaga 10321da177e4SLinus Torvalds memset(req, 0, sizeof(*req)); /* mark unused */ 10331da177e4SLinus Torvalds 103446121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 10351da177e4SLinus Torvalds 10365dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 10371da177e4SLinus Torvalds list_add(&req->rq_list, &xprt->free); 1038555ee3afSChuck Lever rpc_wake_up_next(&xprt->backlog); 10395dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 10401da177e4SLinus Torvalds } 10411da177e4SLinus Torvalds 10429903cd1cSChuck Lever /** 1043c2866763SChuck Lever * xprt_create_transport - create an RPC transport 104496802a09SFrank van Maarseveen * @args: rpc transport creation arguments 1045c2866763SChuck Lever * 1046c2866763SChuck Lever */ 10473c341b0bS\"Talpey, Thomas\ struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 1048c2866763SChuck Lever { 1049c2866763SChuck Lever struct rpc_xprt *xprt; 1050c2866763SChuck Lever struct rpc_rqst *req; 1051bc25571eS\"Talpey, Thomas\ struct xprt_class *t; 1052c2866763SChuck Lever 1053bc25571eS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 1054bc25571eS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 10554fa016ebS\"Talpey, Thomas\ if (t->ident == args->ident) { 1056bc25571eS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 1057bc25571eS\"Talpey, Thomas\ goto found; 1058c2866763SChuck Lever } 1059bc25571eS\"Talpey, Thomas\ } 1060bc25571eS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 10614fa016ebS\"Talpey, Thomas\ printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); 1062bc25571eS\"Talpey, Thomas\ return ERR_PTR(-EIO); 1063bc25571eS\"Talpey, Thomas\ 1064bc25571eS\"Talpey, Thomas\ found: 1065bc25571eS\"Talpey, Thomas\ xprt = t->setup(args); 1066c8541ecdSChuck Lever if (IS_ERR(xprt)) { 1067c8541ecdSChuck Lever dprintk("RPC: xprt_create_transport: failed, %ld\n", 1068c8541ecdSChuck Lever -PTR_ERR(xprt)); 1069c8541ecdSChuck Lever return xprt; 1070c2866763SChuck Lever } 1071c2866763SChuck Lever 10726b6ca86bSTrond Myklebust kref_init(&xprt->kref); 1073c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1074c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 1075c2866763SChuck Lever 1076c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 1077c2866763SChuck Lever INIT_LIST_HEAD(&xprt->recv); 1078f9acac1aSRicardo Labiaga #if defined(CONFIG_NFS_V4_1) 1079f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1080f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 1081f9acac1aSRicardo Labiaga #endif /* CONFIG_NFS_V4_1 */ 1082f9acac1aSRicardo Labiaga 108365f27f38SDavid Howells INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 1084b24b8a24SPavel Emelyanov setup_timer(&xprt->timer, xprt_init_autodisconnect, 1085b24b8a24SPavel Emelyanov (unsigned long)xprt); 1086c2866763SChuck Lever xprt->last_used = jiffies; 1087c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1088a509050bSChuck Lever xprt->bind_index = 0; 1089c2866763SChuck Lever 1090c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1091c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 1092c2866763SChuck Lever rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 1093c2866763SChuck Lever rpc_init_wait_queue(&xprt->resend, "xprt_resend"); 1094c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1095c2866763SChuck Lever 1096c2866763SChuck Lever /* initialize free list */ 1097c2866763SChuck Lever for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) 1098c2866763SChuck Lever list_add(&req->rq_list, &xprt->free); 1099c2866763SChuck Lever 1100c2866763SChuck Lever xprt_init_xid(xprt); 1101c2866763SChuck Lever 1102c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1103c2866763SChuck Lever xprt->max_reqs); 1104c2866763SChuck Lever 1105c2866763SChuck Lever return xprt; 1106c2866763SChuck Lever } 1107c2866763SChuck Lever 11089903cd1cSChuck Lever /** 11099903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 11106b6ca86bSTrond Myklebust * @kref: kref for the transport to destroy 11119903cd1cSChuck Lever * 11121da177e4SLinus Torvalds */ 11136b6ca86bSTrond Myklebust static void xprt_destroy(struct kref *kref) 11141da177e4SLinus Torvalds { 11156b6ca86bSTrond Myklebust struct rpc_xprt *xprt = container_of(kref, struct rpc_xprt, kref); 11166b6ca86bSTrond Myklebust 11171da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 11180065db32STrond Myklebust xprt->shutdown = 1; 11190065db32STrond Myklebust del_timer_sync(&xprt->timer); 1120c8541ecdSChuck Lever 1121f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1122f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1123f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1124f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->resend); 1125f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1126c8541ecdSChuck Lever /* 1127c8541ecdSChuck Lever * Tear down transport state and free the rpc_xprt 1128c8541ecdSChuck Lever */ 1129a246b010SChuck Lever xprt->ops->destroy(xprt); 11306b6ca86bSTrond Myklebust } 11311da177e4SLinus Torvalds 11326b6ca86bSTrond Myklebust /** 11336b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 11346b6ca86bSTrond Myklebust * @xprt: pointer to the transport 11356b6ca86bSTrond Myklebust * 11366b6ca86bSTrond Myklebust */ 11376b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 11386b6ca86bSTrond Myklebust { 11396b6ca86bSTrond Myklebust kref_put(&xprt->kref, xprt_destroy); 11406b6ca86bSTrond Myklebust } 11416b6ca86bSTrond Myklebust 11426b6ca86bSTrond Myklebust /** 11436b6ca86bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 11446b6ca86bSTrond Myklebust * @xprt: pointer to the transport 11456b6ca86bSTrond Myklebust * 11466b6ca86bSTrond Myklebust */ 11476b6ca86bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 11486b6ca86bSTrond Myklebust { 11496b6ca86bSTrond Myklebust kref_get(&xprt->kref); 11506b6ca86bSTrond Myklebust return xprt; 11511da177e4SLinus Torvalds } 1152