11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/net/sunrpc/xprt.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * This is a generic RPC call interface supporting congestion avoidance, 51da177e4SLinus Torvalds * and asynchronous calls. 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * The interface works like this: 81da177e4SLinus Torvalds * 91da177e4SLinus Torvalds * - When a process places a call, it allocates a request slot if 101da177e4SLinus Torvalds * one is available. Otherwise, it sleeps on the backlog queue 111da177e4SLinus Torvalds * (xprt_reserve). 121da177e4SLinus Torvalds * - Next, the caller puts together the RPC message, stuffs it into 1355aa4f58SChuck Lever * the request struct, and calls xprt_transmit(). 1455aa4f58SChuck Lever * - xprt_transmit sends the message and installs the caller on the 1555ae1aabSRicardo Labiaga * transport's wait list. At the same time, if a reply is expected, 1655ae1aabSRicardo Labiaga * it installs a timer that is run after the packet's timeout has 1755ae1aabSRicardo Labiaga * expired. 181da177e4SLinus Torvalds * - When a packet arrives, the data_ready handler walks the list of 1955aa4f58SChuck Lever * pending requests for that transport. If a matching XID is found, the 201da177e4SLinus Torvalds * caller is woken up, and the timer removed. 211da177e4SLinus Torvalds * - When no reply arrives within the timeout interval, the timer is 221da177e4SLinus Torvalds * fired by the kernel and runs xprt_timer(). It either adjusts the 231da177e4SLinus Torvalds * timeout values (minor timeout) or wakes up the caller with a status 241da177e4SLinus Torvalds * of -ETIMEDOUT. 251da177e4SLinus Torvalds * - When the caller receives a notification from RPC that a reply arrived, 261da177e4SLinus Torvalds * it should release the RPC slot, and process the reply. 271da177e4SLinus Torvalds * If the call timed out, it may choose to retry the operation by 281da177e4SLinus Torvalds * adjusting the initial timeout value, and simply calling rpc_call 291da177e4SLinus Torvalds * again. 301da177e4SLinus Torvalds * 311da177e4SLinus Torvalds * Support for async RPC is done through a set of RPC-specific scheduling 321da177e4SLinus Torvalds * primitives that `transparently' work for processes as well as async 331da177e4SLinus Torvalds * tasks that rely on callbacks. 341da177e4SLinus Torvalds * 351da177e4SLinus Torvalds * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> 3655aa4f58SChuck Lever * 3755aa4f58SChuck Lever * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> 381da177e4SLinus Torvalds */ 391da177e4SLinus Torvalds 40a246b010SChuck Lever #include <linux/module.h> 41a246b010SChuck Lever 421da177e4SLinus Torvalds #include <linux/types.h> 43a246b010SChuck Lever #include <linux/interrupt.h> 441da177e4SLinus Torvalds #include <linux/workqueue.h> 45bf3fcf89SChuck Lever #include <linux/net.h> 46ff839970SChuck Lever #include <linux/ktime.h> 471da177e4SLinus Torvalds 48a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 4911c556b3SChuck Lever #include <linux/sunrpc/metrics.h> 50c9acb42eSTrond Myklebust #include <linux/sunrpc/bc_xprt.h> 511da177e4SLinus Torvalds 5255ae1aabSRicardo Labiaga #include "sunrpc.h" 5355ae1aabSRicardo Labiaga 541da177e4SLinus Torvalds /* 551da177e4SLinus Torvalds * Local variables 561da177e4SLinus Torvalds */ 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds #ifdef RPC_DEBUG 591da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 601da177e4SLinus Torvalds #endif 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds /* 631da177e4SLinus Torvalds * Local functions 641da177e4SLinus Torvalds */ 6521de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 661da177e4SLinus Torvalds static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); 671da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 681da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 694e0038b6STrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt); 701da177e4SLinus Torvalds 715ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7281c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7381c098afS\"Talpey, Thomas\ 74555ee3afSChuck Lever /* 75555ee3afSChuck Lever * The transport code maintains an estimate on the maximum number of out- 76555ee3afSChuck Lever * standing RPC requests, using a smoothed version of the congestion 77555ee3afSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 78555ee3afSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 79555ee3afSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 80555ee3afSChuck Lever * 81555ee3afSChuck Lever * - a reply is received and 82555ee3afSChuck Lever * - a full number of requests are outstanding and 83555ee3afSChuck Lever * - the congestion window hasn't been updated recently. 84555ee3afSChuck Lever */ 85555ee3afSChuck Lever #define RPC_CWNDSHIFT (8U) 86555ee3afSChuck Lever #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 87555ee3afSChuck Lever #define RPC_INITCWND RPC_CWNDSCALE 88555ee3afSChuck Lever #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 89555ee3afSChuck Lever 90555ee3afSChuck Lever #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 911da177e4SLinus Torvalds 9212a80469SChuck Lever /** 9381c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 9481c098afS\"Talpey, Thomas\ * @transport: transport to register 9581c098afS\"Talpey, Thomas\ * 9681c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 9781c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 9881c098afS\"Talpey, Thomas\ * 9981c098afS\"Talpey, Thomas\ * Returns: 10081c098afS\"Talpey, Thomas\ * 0: transport successfully registered 10181c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 10281c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 10381c098afS\"Talpey, Thomas\ */ 10481c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 10581c098afS\"Talpey, Thomas\ { 10681c098afS\"Talpey, Thomas\ struct xprt_class *t; 10781c098afS\"Talpey, Thomas\ int result; 10881c098afS\"Talpey, Thomas\ 10981c098afS\"Talpey, Thomas\ result = -EEXIST; 11081c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 11181c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 11281c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 1134fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 11481c098afS\"Talpey, Thomas\ goto out; 11581c098afS\"Talpey, Thomas\ } 11681c098afS\"Talpey, Thomas\ 11781c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 11881c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 11981c098afS\"Talpey, Thomas\ transport->name); 12081c098afS\"Talpey, Thomas\ result = 0; 12181c098afS\"Talpey, Thomas\ 12281c098afS\"Talpey, Thomas\ out: 12381c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 12481c098afS\"Talpey, Thomas\ return result; 12581c098afS\"Talpey, Thomas\ } 12681c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 12781c098afS\"Talpey, Thomas\ 12881c098afS\"Talpey, Thomas\ /** 12981c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 13065b6e42cSRandy Dunlap * @transport: transport to unregister 13181c098afS\"Talpey, Thomas\ * 13281c098afS\"Talpey, Thomas\ * Returns: 13381c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 13481c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 13581c098afS\"Talpey, Thomas\ */ 13681c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 13781c098afS\"Talpey, Thomas\ { 13881c098afS\"Talpey, Thomas\ struct xprt_class *t; 13981c098afS\"Talpey, Thomas\ int result; 14081c098afS\"Talpey, Thomas\ 14181c098afS\"Talpey, Thomas\ result = 0; 14281c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 14381c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 14481c098afS\"Talpey, Thomas\ if (t == transport) { 14581c098afS\"Talpey, Thomas\ printk(KERN_INFO 14681c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 14781c098afS\"Talpey, Thomas\ transport->name); 14881c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 14981c098afS\"Talpey, Thomas\ goto out; 15081c098afS\"Talpey, Thomas\ } 15181c098afS\"Talpey, Thomas\ } 15281c098afS\"Talpey, Thomas\ result = -ENOENT; 15381c098afS\"Talpey, Thomas\ 15481c098afS\"Talpey, Thomas\ out: 15581c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 15681c098afS\"Talpey, Thomas\ return result; 15781c098afS\"Talpey, Thomas\ } 15881c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 15981c098afS\"Talpey, Thomas\ 16081c098afS\"Talpey, Thomas\ /** 161441e3e24STom Talpey * xprt_load_transport - load a transport implementation 162441e3e24STom Talpey * @transport_name: transport to load 163441e3e24STom Talpey * 164441e3e24STom Talpey * Returns: 165441e3e24STom Talpey * 0: transport successfully loaded 166441e3e24STom Talpey * -ENOENT: transport module not available 167441e3e24STom Talpey */ 168441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 169441e3e24STom Talpey { 170441e3e24STom Talpey struct xprt_class *t; 171441e3e24STom Talpey int result; 172441e3e24STom Talpey 173441e3e24STom Talpey result = 0; 174441e3e24STom Talpey spin_lock(&xprt_list_lock); 175441e3e24STom Talpey list_for_each_entry(t, &xprt_list, list) { 176441e3e24STom Talpey if (strcmp(t->name, transport_name) == 0) { 177441e3e24STom Talpey spin_unlock(&xprt_list_lock); 178441e3e24STom Talpey goto out; 179441e3e24STom Talpey } 180441e3e24STom Talpey } 181441e3e24STom Talpey spin_unlock(&xprt_list_lock); 182ef7ffe8fSAlex Riesen result = request_module("xprt%s", transport_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 191177c27bfSRandy Dunlap * @xprt: pointer to the target transport 19212a80469SChuck Lever * 19312a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 19412a80469SChuck Lever * transport connects from colliding with writes. No congestion control 19512a80469SChuck Lever * is provided. 1961da177e4SLinus Torvalds */ 19743cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 1981da177e4SLinus Torvalds { 19912a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 20034006ceeSTrond Myklebust int priority; 20112a80469SChuck Lever 20212a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 20312a80469SChuck Lever if (task == xprt->snd_task) 20412a80469SChuck Lever return 1; 20512a80469SChuck Lever goto out_sleep; 20612a80469SChuck Lever } 20712a80469SChuck Lever xprt->snd_task = task; 20843cedbf0STrond Myklebust if (req != NULL) { 20912a80469SChuck Lever req->rq_bytes_sent = 0; 21012a80469SChuck Lever req->rq_ntrans++; 21143cedbf0STrond Myklebust } 2124d4a76f3Sj223yang@asset.uwaterloo.ca 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; 22034006ceeSTrond Myklebust if (req == NULL) 22134006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 22234006ceeSTrond Myklebust else if (!req->rq_ntrans) 22334006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 22412a80469SChuck Lever else 22534006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 22634006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 22712a80469SChuck Lever return 0; 22812a80469SChuck Lever } 22912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 23012a80469SChuck Lever 231632e3bdcSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 232632e3bdcSTrond Myklebust { 233632e3bdcSTrond Myklebust xprt->snd_task = NULL; 234632e3bdcSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { 235632e3bdcSTrond Myklebust smp_mb__before_clear_bit(); 236632e3bdcSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 237632e3bdcSTrond Myklebust smp_mb__after_clear_bit(); 238632e3bdcSTrond Myklebust } else 239c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 240632e3bdcSTrond Myklebust } 241632e3bdcSTrond Myklebust 24212a80469SChuck Lever /* 24312a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 24412a80469SChuck Lever * @task: task that is requesting access to the transport 24512a80469SChuck Lever * 24612a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 24712a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 24812a80469SChuck Lever * woken up and given access to the transport. 24912a80469SChuck Lever */ 25043cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 25112a80469SChuck Lever { 2521da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 25334006ceeSTrond Myklebust int priority; 2541da177e4SLinus Torvalds 2552226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2561da177e4SLinus Torvalds if (task == xprt->snd_task) 2571da177e4SLinus Torvalds return 1; 2581da177e4SLinus Torvalds goto out_sleep; 2591da177e4SLinus Torvalds } 26043cedbf0STrond Myklebust if (req == NULL) { 26143cedbf0STrond Myklebust xprt->snd_task = task; 26243cedbf0STrond Myklebust return 1; 26343cedbf0STrond Myklebust } 26412a80469SChuck Lever if (__xprt_get_cong(xprt, task)) { 2651da177e4SLinus Torvalds xprt->snd_task = task; 2661da177e4SLinus Torvalds req->rq_bytes_sent = 0; 2671da177e4SLinus Torvalds req->rq_ntrans++; 2681da177e4SLinus Torvalds return 1; 2691da177e4SLinus Torvalds } 270632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2711da177e4SLinus Torvalds out_sleep: 27246121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 2731da177e4SLinus Torvalds task->tk_timeout = 0; 2741da177e4SLinus Torvalds task->tk_status = -EAGAIN; 27534006ceeSTrond Myklebust if (req == NULL) 27634006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 27734006ceeSTrond Myklebust else if (!req->rq_ntrans) 27834006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 2791da177e4SLinus Torvalds else 28034006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 28134006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 2821da177e4SLinus Torvalds return 0; 2831da177e4SLinus Torvalds } 28412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2851da177e4SLinus Torvalds 28612a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2871da177e4SLinus Torvalds { 2881da177e4SLinus Torvalds int retval; 2891da177e4SLinus Torvalds 2904a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 29143cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 2924a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2931da177e4SLinus Torvalds return retval; 2941da177e4SLinus Torvalds } 2951da177e4SLinus Torvalds 296961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 2971da177e4SLinus Torvalds { 298961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 29949e9a890SChuck Lever struct rpc_rqst *req; 30049e9a890SChuck Lever 30149e9a890SChuck Lever req = task->tk_rqstp; 30249e9a890SChuck Lever xprt->snd_task = task; 30349e9a890SChuck Lever if (req) { 30449e9a890SChuck Lever req->rq_bytes_sent = 0; 30549e9a890SChuck Lever req->rq_ntrans++; 30649e9a890SChuck Lever } 307961a828dSTrond Myklebust return true; 308961a828dSTrond Myklebust } 309961a828dSTrond Myklebust 310961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 311961a828dSTrond Myklebust { 312961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 31349e9a890SChuck Lever return; 31449e9a890SChuck Lever 315961a828dSTrond Myklebust if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt)) 316961a828dSTrond Myklebust return; 317632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 31849e9a890SChuck Lever } 31949e9a890SChuck Lever 320961a828dSTrond Myklebust static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) 32149e9a890SChuck Lever { 322961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 32343cedbf0STrond Myklebust struct rpc_rqst *req; 3241da177e4SLinus Torvalds 32543cedbf0STrond Myklebust req = task->tk_rqstp; 32643cedbf0STrond Myklebust if (req == NULL) { 3271da177e4SLinus Torvalds xprt->snd_task = task; 328961a828dSTrond Myklebust return true; 32943cedbf0STrond Myklebust } 33043cedbf0STrond Myklebust if (__xprt_get_cong(xprt, task)) { 33143cedbf0STrond Myklebust xprt->snd_task = task; 3321da177e4SLinus Torvalds req->rq_bytes_sent = 0; 3331da177e4SLinus Torvalds req->rq_ntrans++; 334961a828dSTrond Myklebust return true; 3351da177e4SLinus Torvalds } 336961a828dSTrond Myklebust return false; 337961a828dSTrond Myklebust } 338961a828dSTrond Myklebust 339961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 340961a828dSTrond Myklebust { 341961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 342961a828dSTrond Myklebust return; 343961a828dSTrond Myklebust if (RPCXPRT_CONGESTED(xprt)) 344961a828dSTrond Myklebust goto out_unlock; 345961a828dSTrond Myklebust if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt)) 346961a828dSTrond Myklebust return; 3471da177e4SLinus Torvalds out_unlock: 348632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3491da177e4SLinus Torvalds } 3501da177e4SLinus Torvalds 35149e9a890SChuck Lever /** 35249e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 35349e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 35449e9a890SChuck Lever * @task: task that is releasing access to the transport 35549e9a890SChuck Lever * 35649e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 3571da177e4SLinus Torvalds */ 35849e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3591da177e4SLinus Torvalds { 3601da177e4SLinus Torvalds if (xprt->snd_task == task) { 361632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3621da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3631da177e4SLinus Torvalds } 3641da177e4SLinus Torvalds } 36512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3661da177e4SLinus Torvalds 36749e9a890SChuck Lever /** 36849e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 36949e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 37049e9a890SChuck Lever * @task: task that is releasing access to the transport 37149e9a890SChuck Lever * 37249e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 37349e9a890SChuck Lever * transport if the transport's congestion window allows it. 37449e9a890SChuck Lever */ 37549e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 37649e9a890SChuck Lever { 37749e9a890SChuck Lever if (xprt->snd_task == task) { 378632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 37949e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 38049e9a890SChuck Lever } 38149e9a890SChuck Lever } 38212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 38349e9a890SChuck Lever 38449e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3851da177e4SLinus Torvalds { 3864a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 38749e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3884a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3891da177e4SLinus Torvalds } 3901da177e4SLinus Torvalds 3911da177e4SLinus Torvalds /* 3921da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3931da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3941da177e4SLinus Torvalds */ 3951da177e4SLinus Torvalds static int 3961da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 3971da177e4SLinus Torvalds { 3981da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3991da177e4SLinus Torvalds 4001da177e4SLinus Torvalds if (req->rq_cong) 4011da177e4SLinus Torvalds return 1; 40246121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 4031da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 4041da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 4051da177e4SLinus Torvalds return 0; 4061da177e4SLinus Torvalds req->rq_cong = 1; 4071da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 4081da177e4SLinus Torvalds return 1; 4091da177e4SLinus Torvalds } 4101da177e4SLinus Torvalds 4111da177e4SLinus Torvalds /* 4121da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4131da177e4SLinus Torvalds * that has been sleeping due to congestion 4141da177e4SLinus Torvalds */ 4151da177e4SLinus Torvalds static void 4161da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4171da177e4SLinus Torvalds { 4181da177e4SLinus Torvalds if (!req->rq_cong) 4191da177e4SLinus Torvalds return; 4201da177e4SLinus Torvalds req->rq_cong = 0; 4211da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 42249e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4231da177e4SLinus Torvalds } 4241da177e4SLinus Torvalds 42546c0ee8bSChuck Lever /** 426a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 427a58dd398SChuck Lever * @task: RPC request that recently completed 428a58dd398SChuck Lever * 429a58dd398SChuck Lever * Useful for transports that require congestion control. 430a58dd398SChuck Lever */ 431a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 432a58dd398SChuck Lever { 433a58dd398SChuck Lever __xprt_put_cong(task->tk_xprt, task->tk_rqstp); 434a58dd398SChuck Lever } 43512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 436a58dd398SChuck Lever 437a58dd398SChuck Lever /** 43846c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 43946c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 44046c0ee8bSChuck Lever * @result: result code of completed RPC request 44146c0ee8bSChuck Lever * 4421da177e4SLinus Torvalds * We use a time-smoothed congestion estimator to avoid heavy oscillation. 4431da177e4SLinus Torvalds */ 44446c0ee8bSChuck Lever void xprt_adjust_cwnd(struct rpc_task *task, int result) 4451da177e4SLinus Torvalds { 44646c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 44746c0ee8bSChuck Lever struct rpc_xprt *xprt = task->tk_xprt; 44846c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4491da177e4SLinus Torvalds 4501da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4511da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4521da177e4SLinus Torvalds * the result gets rounded properly. */ 4531da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4541da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4551da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 45649e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4571da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4581da177e4SLinus Torvalds cwnd >>= 1; 4591da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4601da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4611da177e4SLinus Torvalds } 4621da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4631da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4641da177e4SLinus Torvalds xprt->cwnd = cwnd; 46546c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4661da177e4SLinus Torvalds } 46712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4681da177e4SLinus Torvalds 46944fbac22SChuck Lever /** 47044fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 47144fbac22SChuck Lever * @xprt: transport with waiting tasks 47244fbac22SChuck Lever * @status: result code to plant in each task before waking it 47344fbac22SChuck Lever * 47444fbac22SChuck Lever */ 47544fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 47644fbac22SChuck Lever { 47744fbac22SChuck Lever if (status < 0) 47844fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 47944fbac22SChuck Lever else 48044fbac22SChuck Lever rpc_wake_up(&xprt->pending); 48144fbac22SChuck Lever } 48212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 48344fbac22SChuck Lever 484c7b2cae8SChuck Lever /** 485c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 486c7b2cae8SChuck Lever * @task: task to be put to sleep 4870b80ae42SRandy Dunlap * @action: function pointer to be executed after wait 488c7b2cae8SChuck Lever */ 489b6ddf64fSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) 490c7b2cae8SChuck Lever { 491c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 492c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 493c7b2cae8SChuck Lever 494c7b2cae8SChuck Lever task->tk_timeout = req->rq_timeout; 495b6ddf64fSTrond Myklebust rpc_sleep_on(&xprt->pending, task, action); 496c7b2cae8SChuck Lever } 49712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 498c7b2cae8SChuck Lever 499c7b2cae8SChuck Lever /** 500c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 501c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 502c7b2cae8SChuck Lever * 503c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 504c7b2cae8SChuck Lever */ 505c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 506c7b2cae8SChuck Lever { 507c7b2cae8SChuck Lever if (unlikely(xprt->shutdown)) 508c7b2cae8SChuck Lever return; 509c7b2cae8SChuck Lever 510c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 511c7b2cae8SChuck Lever if (xprt->snd_task) { 51246121cf7SChuck Lever dprintk("RPC: write space: waking waiting task on " 51346121cf7SChuck Lever "xprt %p\n", xprt); 514fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); 515c7b2cae8SChuck Lever } 516c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 517c7b2cae8SChuck Lever } 51812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 519c7b2cae8SChuck Lever 520fe3aca29SChuck Lever /** 521fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 522fe3aca29SChuck Lever * @task: task whose timeout is to be set 523fe3aca29SChuck Lever * 524fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 525fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 526fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 527fe3aca29SChuck Lever */ 528fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 529fe3aca29SChuck Lever { 530fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 531fe3aca29SChuck Lever } 53212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 533fe3aca29SChuck Lever 5342c53040fSBen Hutchings /** 535fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout 536fe3aca29SChuck Lever * @task: task whose timeout is to be set 537fe3aca29SChuck Lever * 538fe3aca29SChuck Lever * Set a request's retransmit timeout using the RTT estimator. 539fe3aca29SChuck Lever */ 540fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 541fe3aca29SChuck Lever { 542fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 543ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 544ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 545fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 546ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 547fe3aca29SChuck Lever 548fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 549fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 550fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 551fe3aca29SChuck Lever task->tk_timeout = max_timeout; 552fe3aca29SChuck Lever } 55312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 554fe3aca29SChuck Lever 5551da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5561da177e4SLinus Torvalds { 557ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5581da177e4SLinus Torvalds 5591da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5601da177e4SLinus Torvalds if (to->to_exponential) 5611da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5621da177e4SLinus Torvalds else 5631da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 5641da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 5651da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 5661da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 5671da177e4SLinus Torvalds } 5681da177e4SLinus Torvalds 5699903cd1cSChuck Lever /** 5709903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 5719903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 5729903cd1cSChuck Lever * 5731da177e4SLinus Torvalds */ 5741da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 5751da177e4SLinus Torvalds { 5761da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 577ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5781da177e4SLinus Torvalds int status = 0; 5791da177e4SLinus Torvalds 5801da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 5811da177e4SLinus Torvalds if (to->to_exponential) 5821da177e4SLinus Torvalds req->rq_timeout <<= 1; 5831da177e4SLinus Torvalds else 5841da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 5851da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 5861da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 5871da177e4SLinus Torvalds req->rq_retries++; 5881da177e4SLinus Torvalds } else { 5891da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 5901da177e4SLinus Torvalds req->rq_retries = 0; 5911da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5921da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 5934a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5941da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 5954a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5961da177e4SLinus Torvalds status = -ETIMEDOUT; 5971da177e4SLinus Torvalds } 5981da177e4SLinus Torvalds 5991da177e4SLinus Torvalds if (req->rq_timeout == 0) { 6001da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 6011da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 6021da177e4SLinus Torvalds } 6031da177e4SLinus Torvalds return status; 6041da177e4SLinus Torvalds } 6051da177e4SLinus Torvalds 60665f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 6071da177e4SLinus Torvalds { 60865f27f38SDavid Howells struct rpc_xprt *xprt = 60965f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 6101da177e4SLinus Torvalds 611a246b010SChuck Lever xprt->ops->close(xprt); 61266af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 6131da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 6141da177e4SLinus Torvalds } 6151da177e4SLinus Torvalds 6169903cd1cSChuck Lever /** 61762da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6189903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6199903cd1cSChuck Lever * 6201da177e4SLinus Torvalds */ 62162da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6221da177e4SLinus Torvalds { 6231da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6244a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6251da177e4SLinus Torvalds xprt_clear_connected(xprt); 6262a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6274a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6281da177e4SLinus Torvalds } 62962da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6301da177e4SLinus Torvalds 63166af1e55STrond Myklebust /** 63266af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 63366af1e55STrond Myklebust * @xprt: transport to disconnect 63466af1e55STrond Myklebust * 63566af1e55STrond Myklebust */ 63666af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 63766af1e55STrond Myklebust { 63866af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 63966af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 64066af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 64166af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 64266af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 64366af1e55STrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6442a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 64566af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 64666af1e55STrond Myklebust } 64766af1e55STrond Myklebust 6487c1d71cfSTrond Myklebust /** 6497c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 6507c1d71cfSTrond Myklebust * @xprt: transport to disconnect 6517c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 6527c1d71cfSTrond Myklebust * 6537c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 6547c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 6557c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 6567c1d71cfSTrond Myklebust * a batch of RPC requests. 6577c1d71cfSTrond Myklebust * 6587c1d71cfSTrond Myklebust */ 6597c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 6607c1d71cfSTrond Myklebust { 6617c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 6627c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 6637c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 6647c1d71cfSTrond Myklebust goto out; 6657c1d71cfSTrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) 6667c1d71cfSTrond Myklebust goto out; 6677c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 6687c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 6697c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 6707c1d71cfSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6712a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6727c1d71cfSTrond Myklebust out: 6737c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 6747c1d71cfSTrond Myklebust } 6757c1d71cfSTrond Myklebust 6761da177e4SLinus Torvalds static void 6771da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 6781da177e4SLinus Torvalds { 6791da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 6801da177e4SLinus Torvalds 6814a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 6821da177e4SLinus Torvalds if (!list_empty(&xprt->recv) || xprt->shutdown) 6831da177e4SLinus Torvalds goto out_abort; 6842226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 6851da177e4SLinus Torvalds goto out_abort; 6864a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 687f75e6745STrond Myklebust set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); 688c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6891da177e4SLinus Torvalds return; 6901da177e4SLinus Torvalds out_abort: 6914a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 6921da177e4SLinus Torvalds } 6931da177e4SLinus Torvalds 6949903cd1cSChuck Lever /** 6959903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 6969903cd1cSChuck Lever * @task: RPC task that is requesting the connect 6971da177e4SLinus Torvalds * 6981da177e4SLinus Torvalds */ 6991da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 7001da177e4SLinus Torvalds { 7011da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 7021da177e4SLinus Torvalds 70346121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 7041da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 7051da177e4SLinus Torvalds 706ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 70701d37c42STrond Myklebust task->tk_status = -EAGAIN; 7081da177e4SLinus Torvalds return; 7091da177e4SLinus Torvalds } 7101da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 7111da177e4SLinus Torvalds return; 712feb8ca37STrond Myklebust 713feb8ca37STrond Myklebust if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) 714feb8ca37STrond Myklebust xprt->ops->close(xprt); 715feb8ca37STrond Myklebust 7161da177e4SLinus Torvalds if (xprt_connected(xprt)) 717a246b010SChuck Lever xprt_release_write(xprt, task); 718a246b010SChuck Lever else { 7191da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 720a8ce4a8fSTrond Myklebust task->tk_timeout = task->tk_rqstp->rq_timeout; 7215d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_connect_status); 7220b9e7943STrond Myklebust 7230b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 7240b9e7943STrond Myklebust return; 7250b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 7260b9e7943STrond Myklebust return; 727262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 728a246b010SChuck Lever xprt->ops->connect(task); 7291da177e4SLinus Torvalds } 7301da177e4SLinus Torvalds } 7311da177e4SLinus Torvalds 7329903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 7331da177e4SLinus Torvalds { 7341da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 7351da177e4SLinus Torvalds 736cd983ef8SChuck Lever if (task->tk_status == 0) { 737262ca07dSChuck Lever xprt->stat.connect_count++; 738262ca07dSChuck Lever xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; 73946121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connection established\n", 7401da177e4SLinus Torvalds task->tk_pid); 7411da177e4SLinus Torvalds return; 7421da177e4SLinus Torvalds } 7431da177e4SLinus Torvalds 7441da177e4SLinus Torvalds switch (task->tk_status) { 7452a491991STrond Myklebust case -EAGAIN: 7462a491991STrond Myklebust dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); 74723475d66SChuck Lever break; 7481da177e4SLinus Torvalds case -ETIMEDOUT: 74946121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connect attempt timed " 75046121cf7SChuck Lever "out\n", task->tk_pid); 7511da177e4SLinus Torvalds break; 7521da177e4SLinus Torvalds default: 75346121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: error %d connecting to " 75446121cf7SChuck Lever "server %s\n", task->tk_pid, -task->tk_status, 7554e0038b6STrond Myklebust xprt->servername); 7561da177e4SLinus Torvalds xprt_release_write(xprt, task); 75723475d66SChuck Lever task->tk_status = -EIO; 75823475d66SChuck Lever } 7591da177e4SLinus Torvalds } 7601da177e4SLinus Torvalds 7619903cd1cSChuck Lever /** 7629903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 7639903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 7649903cd1cSChuck Lever * @xid: RPC XID of incoming reply 7659903cd1cSChuck Lever * 7661da177e4SLinus Torvalds */ 767d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 7681da177e4SLinus Torvalds { 7698f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 7701da177e4SLinus Torvalds 7718f3a6de3SPavel Emelyanov list_for_each_entry(entry, &xprt->recv, rq_list) 772262ca07dSChuck Lever if (entry->rq_xid == xid) 773262ca07dSChuck Lever return entry; 77446121cf7SChuck Lever 77546121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 77646121cf7SChuck Lever ntohl(xid)); 777262ca07dSChuck Lever xprt->stat.bad_xids++; 778262ca07dSChuck Lever return NULL; 7791da177e4SLinus Torvalds } 78012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 7811da177e4SLinus Torvalds 782bbc72ceaSChuck Lever static void xprt_update_rtt(struct rpc_task *task) 7831da177e4SLinus Torvalds { 7841570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 7851570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 78695c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 787d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 7881570c1e4SChuck Lever 7891da177e4SLinus Torvalds if (timer) { 7901da177e4SLinus Torvalds if (req->rq_ntrans == 1) 791ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 7921570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 7931da177e4SLinus Torvalds } 7941da177e4SLinus Torvalds } 7951da177e4SLinus Torvalds 7961570c1e4SChuck Lever /** 7971570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 7981570c1e4SChuck Lever * @task: RPC request that recently completed 7991570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 8001570c1e4SChuck Lever * 8011570c1e4SChuck Lever * Caller holds transport lock. 8021570c1e4SChuck Lever */ 8031570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 8041570c1e4SChuck Lever { 8051570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 806fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 8071da177e4SLinus Torvalds 8081570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 8091570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 8101da177e4SLinus Torvalds 811fda13939STrond Myklebust xprt->stat.recvs++; 812d60dbb20STrond Myklebust req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); 813bbc72ceaSChuck Lever if (xprt->ops->timer != NULL) 814bbc72ceaSChuck Lever xprt_update_rtt(task); 815ef759a2eSChuck Lever 8161da177e4SLinus Torvalds list_del_init(&req->rq_list); 8171e799b67STrond Myklebust req->rq_private_buf.len = copied; 818dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 819dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 82043ac3f29STrond Myklebust smp_wmb(); 821dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 822fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 8231da177e4SLinus Torvalds } 82412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 8251da177e4SLinus Torvalds 82646c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 8271da177e4SLinus Torvalds { 8281da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8291da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8301da177e4SLinus Torvalds 8315d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 8325d00837bSTrond Myklebust return; 83346121cf7SChuck Lever dprintk("RPC: %5u xprt_timer\n", task->tk_pid); 83446c0ee8bSChuck Lever 8355d00837bSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 836dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 83746c0ee8bSChuck Lever if (xprt->ops->timer) 83846c0ee8bSChuck Lever xprt->ops->timer(task); 8395d00837bSTrond Myklebust } else 8405d00837bSTrond Myklebust task->tk_status = 0; 8415d00837bSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 8421da177e4SLinus Torvalds } 8431da177e4SLinus Torvalds 8444cfc7e60SRahul Iyer static inline int xprt_has_timer(struct rpc_xprt *xprt) 8454cfc7e60SRahul Iyer { 8464cfc7e60SRahul Iyer return xprt->idle_timeout != 0; 8474cfc7e60SRahul Iyer } 8484cfc7e60SRahul Iyer 8499903cd1cSChuck Lever /** 8509903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 8519903cd1cSChuck Lever * @task: RPC task about to send a request 8529903cd1cSChuck Lever * 8531da177e4SLinus Torvalds */ 8549903cd1cSChuck Lever int xprt_prepare_transmit(struct rpc_task *task) 8551da177e4SLinus Torvalds { 8561da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8571da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8581da177e4SLinus Torvalds int err = 0; 8591da177e4SLinus Torvalds 86046121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 8611da177e4SLinus Torvalds 8624a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 863dd2b63d0SRicardo Labiaga if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) { 864dd2b63d0SRicardo Labiaga err = req->rq_reply_bytes_recvd; 8651da177e4SLinus Torvalds goto out_unlock; 8661da177e4SLinus Torvalds } 86743cedbf0STrond Myklebust if (!xprt->ops->reserve_xprt(xprt, task)) 8681da177e4SLinus Torvalds err = -EAGAIN; 8691da177e4SLinus Torvalds out_unlock: 8704a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 8711da177e4SLinus Torvalds return err; 8721da177e4SLinus Torvalds } 8731da177e4SLinus Torvalds 874e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 8755e5ce5beSTrond Myklebust { 876343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 8775e5ce5beSTrond Myklebust } 8785e5ce5beSTrond Myklebust 8799903cd1cSChuck Lever /** 8809903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 8819903cd1cSChuck Lever * @task: controlling RPC task 8829903cd1cSChuck Lever * 8839903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 8849903cd1cSChuck Lever */ 8859903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 8861da177e4SLinus Torvalds { 8871da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8881da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 88915a45206SAndy Adamson int status, numreqs; 8901da177e4SLinus Torvalds 89146121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 8921da177e4SLinus Torvalds 893dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 89455ae1aabSRicardo Labiaga if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { 89555ae1aabSRicardo Labiaga /* 89655ae1aabSRicardo Labiaga * Add to the list only if we're expecting a reply 89755ae1aabSRicardo Labiaga */ 8984a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 8991da177e4SLinus Torvalds /* Update the softirq receive buffer */ 9001da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 9011da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 9021da177e4SLinus Torvalds /* Add request to the receive list */ 9031da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 9044a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9051da177e4SLinus Torvalds xprt_reset_majortimeo(req); 9060f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 9070f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 9081da177e4SLinus Torvalds } 9091da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 9101da177e4SLinus Torvalds return; 9111da177e4SLinus Torvalds 9127c1d71cfSTrond Myklebust req->rq_connect_cookie = xprt->connect_cookie; 913ff839970SChuck Lever req->rq_xtime = ktime_get(); 914a246b010SChuck Lever status = xprt->ops->send_request(task); 915c8485e4dSTrond Myklebust if (status != 0) { 916c8485e4dSTrond Myklebust task->tk_status = status; 917c8485e4dSTrond Myklebust return; 918c8485e4dSTrond Myklebust } 919c8485e4dSTrond Myklebust 92046121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 921468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 922fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 923262ca07dSChuck Lever 924fe3aca29SChuck Lever xprt->ops->set_retrans_timeout(task); 925262ca07dSChuck Lever 92615a45206SAndy Adamson numreqs = atomic_read(&xprt->num_reqs); 92715a45206SAndy Adamson if (numreqs > xprt->stat.max_slots) 92815a45206SAndy Adamson xprt->stat.max_slots = numreqs; 929262ca07dSChuck Lever xprt->stat.sends++; 930262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 931262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 93215a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 93315a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 934262ca07dSChuck Lever 935fe3aca29SChuck Lever /* Don't race with disconnect */ 936fe3aca29SChuck Lever if (!xprt_connected(xprt)) 937fe3aca29SChuck Lever task->tk_status = -ENOTCONN; 938dd2b63d0SRicardo Labiaga else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) { 93955ae1aabSRicardo Labiaga /* 94055ae1aabSRicardo Labiaga * Sleep on the pending queue since 94155ae1aabSRicardo Labiaga * we're expecting a reply. 94255ae1aabSRicardo Labiaga */ 9435d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 94455ae1aabSRicardo Labiaga } 945fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9461da177e4SLinus Torvalds } 9471da177e4SLinus Torvalds 948d9ba131dSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) 949d9ba131dSTrond Myklebust { 950d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 951d9ba131dSTrond Myklebust 952d9ba131dSTrond Myklebust if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) 953d9ba131dSTrond Myklebust goto out; 954d9ba131dSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); 955d9ba131dSTrond Myklebust if (req != NULL) 956d9ba131dSTrond Myklebust goto out; 957d9ba131dSTrond Myklebust atomic_dec(&xprt->num_reqs); 958d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 959d9ba131dSTrond Myklebust out: 960d9ba131dSTrond Myklebust return req; 961d9ba131dSTrond Myklebust } 962d9ba131dSTrond Myklebust 963d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 964d9ba131dSTrond Myklebust { 965d9ba131dSTrond Myklebust if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { 966d9ba131dSTrond Myklebust kfree(req); 967d9ba131dSTrond Myklebust return true; 968d9ba131dSTrond Myklebust } 969d9ba131dSTrond Myklebust return false; 970d9ba131dSTrond Myklebust } 971d9ba131dSTrond Myklebust 972ee5ebe85STrond Myklebust static void xprt_alloc_slot(struct rpc_task *task) 9731da177e4SLinus Torvalds { 9741da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 975d9ba131dSTrond Myklebust struct rpc_rqst *req; 9761da177e4SLinus Torvalds 9771da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 978d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 979d9ba131dSTrond Myklebust list_del(&req->rq_list); 980d9ba131dSTrond Myklebust goto out_init_req; 981d9ba131dSTrond Myklebust } 9826b343099SJeff Layton req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN); 983d9ba131dSTrond Myklebust if (!IS_ERR(req)) 984d9ba131dSTrond Myklebust goto out_init_req; 985d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 986d9ba131dSTrond Myklebust case -ENOMEM: 987d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 988d9ba131dSTrond Myklebust "failed! Retrying\n"); 9891afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 990d9ba131dSTrond Myklebust break; 991d9ba131dSTrond Myklebust case -EAGAIN: 992d9ba131dSTrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 993d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 9941afeaf5cSTrond Myklebust default: 995d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 9961afeaf5cSTrond Myklebust } 997d9ba131dSTrond Myklebust return; 998d9ba131dSTrond Myklebust out_init_req: 999d9ba131dSTrond Myklebust task->tk_status = 0; 10001da177e4SLinus Torvalds task->tk_rqstp = req; 10011da177e4SLinus Torvalds xprt_request_init(task, xprt); 10021da177e4SLinus Torvalds } 10031da177e4SLinus Torvalds 1004ee5ebe85STrond Myklebust static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1005ee5ebe85STrond Myklebust { 1006ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1007c25573b5STrond Myklebust if (!xprt_dynamic_free_slot(xprt, req)) { 1008c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1009ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1010c25573b5STrond Myklebust } 1011ee5ebe85STrond Myklebust rpc_wake_up_next(&xprt->backlog); 1012ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1013ee5ebe85STrond Myklebust } 1014ee5ebe85STrond Myklebust 101521de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 101621de0a95STrond Myklebust { 101721de0a95STrond Myklebust struct rpc_rqst *req; 101821de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 101921de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 102021de0a95STrond Myklebust list_del(&req->rq_list); 102121de0a95STrond Myklebust kfree(req); 102221de0a95STrond Myklebust } 102321de0a95STrond Myklebust } 102421de0a95STrond Myklebust 1025d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1026d9ba131dSTrond Myklebust unsigned int num_prealloc, 1027d9ba131dSTrond Myklebust unsigned int max_alloc) 1028bd1722d4SPavel Emelyanov { 1029bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 103021de0a95STrond Myklebust struct rpc_rqst *req; 103121de0a95STrond Myklebust int i; 1032bd1722d4SPavel Emelyanov 1033bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1034bd1722d4SPavel Emelyanov if (xprt == NULL) 1035bd1722d4SPavel Emelyanov goto out; 1036bd1722d4SPavel Emelyanov 103721de0a95STrond Myklebust xprt_init(xprt, net); 103821de0a95STrond Myklebust 103921de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 104021de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 104121de0a95STrond Myklebust if (!req) 104221de0a95STrond Myklebust break; 104321de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 104421de0a95STrond Myklebust } 104521de0a95STrond Myklebust if (i < num_prealloc) 1046bd1722d4SPavel Emelyanov goto out_free; 1047d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1048d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1049d9ba131dSTrond Myklebust else 105021de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1051d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1052d9ba131dSTrond Myklebust atomic_set(&xprt->num_reqs, num_prealloc); 1053bd1722d4SPavel Emelyanov 1054bd1722d4SPavel Emelyanov return xprt; 1055bd1722d4SPavel Emelyanov 1056bd1722d4SPavel Emelyanov out_free: 105721de0a95STrond Myklebust xprt_free(xprt); 1058bd1722d4SPavel Emelyanov out: 1059bd1722d4SPavel Emelyanov return NULL; 1060bd1722d4SPavel Emelyanov } 1061bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1062bd1722d4SPavel Emelyanov 1063e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1064e204e621SPavel Emelyanov { 106537aa2133SPavel Emelyanov put_net(xprt->xprt_net); 106621de0a95STrond Myklebust xprt_free_all_slots(xprt); 1067e204e621SPavel Emelyanov kfree(xprt); 1068e204e621SPavel Emelyanov } 1069e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1070e204e621SPavel Emelyanov 10719903cd1cSChuck Lever /** 10729903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 10739903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 10749903cd1cSChuck Lever * 10759903cd1cSChuck Lever * If no more slots are available, place the task on the transport's 10769903cd1cSChuck Lever * backlog queue. 10779903cd1cSChuck Lever */ 10789903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 10791da177e4SLinus Torvalds { 10801da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 10811da177e4SLinus Torvalds 108243cedbf0STrond Myklebust task->tk_status = 0; 108343cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 108443cedbf0STrond Myklebust return; 108543cedbf0STrond Myklebust 108643cedbf0STrond Myklebust /* Note: grabbing the xprt_lock_write() here is not strictly needed, 108743cedbf0STrond Myklebust * but ensures that we throttle new slot allocation if the transport 108843cedbf0STrond Myklebust * is congested (e.g. if reconnecting or if we're out of socket 108943cedbf0STrond Myklebust * write buffer space). 109043cedbf0STrond Myklebust */ 109143cedbf0STrond Myklebust task->tk_timeout = 0; 109243cedbf0STrond Myklebust task->tk_status = -EAGAIN; 109343cedbf0STrond Myklebust if (!xprt_lock_write(xprt, task)) 109443cedbf0STrond Myklebust return; 109543cedbf0STrond Myklebust 10965dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 1097ee5ebe85STrond Myklebust xprt_alloc_slot(task); 10985dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 109943cedbf0STrond Myklebust xprt_release_write(xprt, task); 11001da177e4SLinus Torvalds } 11011da177e4SLinus Torvalds 1102d8ed029dSAlexey Dobriyan static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) 11031da177e4SLinus Torvalds { 11040eae88f3SEric Dumazet return (__force __be32)xprt->xid++; 11051da177e4SLinus Torvalds } 11061da177e4SLinus Torvalds 11071da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 11081da177e4SLinus Torvalds { 1109bf3fcf89SChuck Lever xprt->xid = net_random(); 11101da177e4SLinus Torvalds } 11111da177e4SLinus Torvalds 11129903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 11131da177e4SLinus Torvalds { 11141da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 11151da177e4SLinus Torvalds 1116d9ba131dSTrond Myklebust INIT_LIST_HEAD(&req->rq_list); 1117ba7392bbSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 11181da177e4SLinus Torvalds req->rq_task = task; 11191da177e4SLinus Torvalds req->rq_xprt = xprt; 112002107148SChuck Lever req->rq_buffer = NULL; 11211da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 1122ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf = NULL; 1123da45828eSTrond Myklebust xprt_reset_majortimeo(req); 112446121cf7SChuck Lever dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 11251da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 11261da177e4SLinus Torvalds } 11271da177e4SLinus Torvalds 11289903cd1cSChuck Lever /** 11299903cd1cSChuck Lever * xprt_release - release an RPC request slot 11309903cd1cSChuck Lever * @task: task which is finished with the slot 11319903cd1cSChuck Lever * 11321da177e4SLinus Torvalds */ 11339903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 11341da177e4SLinus Torvalds { 113555ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 11361da177e4SLinus Torvalds struct rpc_rqst *req; 11371da177e4SLinus Torvalds 11381da177e4SLinus Torvalds if (!(req = task->tk_rqstp)) 11391da177e4SLinus Torvalds return; 114055ae1aabSRicardo Labiaga 114155ae1aabSRicardo Labiaga xprt = req->rq_xprt; 11420a702195SWeston Andros Adamson if (task->tk_ops->rpc_count_stats != NULL) 11430a702195SWeston Andros Adamson task->tk_ops->rpc_count_stats(task, task->tk_calldata); 11440a702195SWeston Andros Adamson else if (task->tk_client) 11450a702195SWeston Andros Adamson rpc_count_iostats(task, task->tk_client->cl_metrics); 11464a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 114749e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1148a58dd398SChuck Lever if (xprt->ops->release_request) 1149a58dd398SChuck Lever xprt->ops->release_request(task); 11501da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 11511da177e4SLinus Torvalds list_del(&req->rq_list); 11521da177e4SLinus Torvalds xprt->last_used = jiffies; 11534cfc7e60SRahul Iyer if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) 1154a246b010SChuck Lever mod_timer(&xprt->timer, 115503bf4b70SChuck Lever xprt->last_used + xprt->idle_timeout); 11564a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1157ee5ebe85STrond Myklebust if (req->rq_buffer) 1158c5a4dd8bSChuck Lever xprt->ops->buf_free(req->rq_buffer); 1159a17c2153STrond Myklebust if (req->rq_cred != NULL) 1160a17c2153STrond Myklebust put_rpccred(req->rq_cred); 11611da177e4SLinus Torvalds task->tk_rqstp = NULL; 1162ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1163ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 116455ae1aabSRicardo Labiaga 116546121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 1166ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1167ee5ebe85STrond Myklebust xprt_free_slot(xprt, req); 1168ee5ebe85STrond Myklebust else 1169c9acb42eSTrond Myklebust xprt_free_bc_request(req); 11701da177e4SLinus Torvalds } 11711da177e4SLinus Torvalds 117221de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1173c2866763SChuck Lever { 117421de0a95STrond Myklebust atomic_set(&xprt->count, 1); 1175c2866763SChuck Lever 1176c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1177c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 1178c2866763SChuck Lever 1179c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 1180c2866763SChuck Lever INIT_LIST_HEAD(&xprt->recv); 11819e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1182f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1183f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 11849e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1185f9acac1aSRicardo Labiaga 1186c2866763SChuck Lever xprt->last_used = jiffies; 1187c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1188a509050bSChuck Lever xprt->bind_index = 0; 1189c2866763SChuck Lever 1190c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1191c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 119234006ceeSTrond Myklebust rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); 1193c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1194c2866763SChuck Lever 1195c2866763SChuck Lever xprt_init_xid(xprt); 1196c2866763SChuck Lever 119721de0a95STrond Myklebust xprt->xprt_net = get_net(net); 11988d9266ffSTrond Myklebust } 11998d9266ffSTrond Myklebust 12008d9266ffSTrond Myklebust /** 12018d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 12028d9266ffSTrond Myklebust * @args: rpc transport creation arguments 12038d9266ffSTrond Myklebust * 12048d9266ffSTrond Myklebust */ 12058d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 12068d9266ffSTrond Myklebust { 12078d9266ffSTrond Myklebust struct rpc_xprt *xprt; 12088d9266ffSTrond Myklebust struct xprt_class *t; 12098d9266ffSTrond Myklebust 12108d9266ffSTrond Myklebust spin_lock(&xprt_list_lock); 12118d9266ffSTrond Myklebust list_for_each_entry(t, &xprt_list, list) { 12128d9266ffSTrond Myklebust if (t->ident == args->ident) { 12138d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 12148d9266ffSTrond Myklebust goto found; 12158d9266ffSTrond Myklebust } 12168d9266ffSTrond Myklebust } 12178d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 12188d9266ffSTrond Myklebust printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); 12198d9266ffSTrond Myklebust return ERR_PTR(-EIO); 12208d9266ffSTrond Myklebust 12218d9266ffSTrond Myklebust found: 12228d9266ffSTrond Myklebust xprt = t->setup(args); 12238d9266ffSTrond Myklebust if (IS_ERR(xprt)) { 12248d9266ffSTrond Myklebust dprintk("RPC: xprt_create_transport: failed, %ld\n", 12258d9266ffSTrond Myklebust -PTR_ERR(xprt)); 122621de0a95STrond Myklebust goto out; 12278d9266ffSTrond Myklebust } 122821de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 122921de0a95STrond Myklebust if (xprt_has_timer(xprt)) 123021de0a95STrond Myklebust setup_timer(&xprt->timer, xprt_init_autodisconnect, 123121de0a95STrond Myklebust (unsigned long)xprt); 123221de0a95STrond Myklebust else 123321de0a95STrond Myklebust init_timer(&xprt->timer); 12344e0038b6STrond Myklebust 12354e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 12364e0038b6STrond Myklebust xprt_destroy(xprt); 12374e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 12384e0038b6STrond Myklebust } 12394e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 12404e0038b6STrond Myklebust if (xprt->servername == NULL) { 12414e0038b6STrond Myklebust xprt_destroy(xprt); 12424e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 12434e0038b6STrond Myklebust } 12444e0038b6STrond Myklebust 1245c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1246c2866763SChuck Lever xprt->max_reqs); 124721de0a95STrond Myklebust out: 1248c2866763SChuck Lever return xprt; 1249c2866763SChuck Lever } 1250c2866763SChuck Lever 12519903cd1cSChuck Lever /** 12529903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 1253a8de240aSTrond Myklebust * @xprt: transport to destroy 12549903cd1cSChuck Lever * 12551da177e4SLinus Torvalds */ 1256a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 12571da177e4SLinus Torvalds { 12581da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 12590065db32STrond Myklebust xprt->shutdown = 1; 12600065db32STrond Myklebust del_timer_sync(&xprt->timer); 1261c8541ecdSChuck Lever 1262f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1263f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1264f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1265f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1266c3ae62aeSJ. Bruce Fields cancel_work_sync(&xprt->task_cleanup); 12674e0038b6STrond Myklebust kfree(xprt->servername); 1268c8541ecdSChuck Lever /* 1269c8541ecdSChuck Lever * Tear down transport state and free the rpc_xprt 1270c8541ecdSChuck Lever */ 1271a246b010SChuck Lever xprt->ops->destroy(xprt); 12726b6ca86bSTrond Myklebust } 12731da177e4SLinus Torvalds 12746b6ca86bSTrond Myklebust /** 12756b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 12766b6ca86bSTrond Myklebust * @xprt: pointer to the transport 12776b6ca86bSTrond Myklebust * 12786b6ca86bSTrond Myklebust */ 12796b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 12806b6ca86bSTrond Myklebust { 1281a8de240aSTrond Myklebust if (atomic_dec_and_test(&xprt->count)) 1282a8de240aSTrond Myklebust xprt_destroy(xprt); 12836b6ca86bSTrond Myklebust } 12846b6ca86bSTrond Myklebust 12856b6ca86bSTrond Myklebust /** 12866b6ca86bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 12876b6ca86bSTrond Myklebust * @xprt: pointer to the transport 12886b6ca86bSTrond Myklebust * 12896b6ca86bSTrond Myklebust */ 12906b6ca86bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 12916b6ca86bSTrond Myklebust { 1292a8de240aSTrond Myklebust if (atomic_inc_not_zero(&xprt->count)) 12936b6ca86bSTrond Myklebust return xprt; 1294a8de240aSTrond Myklebust return NULL; 12951da177e4SLinus Torvalds } 1296