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> 51fda1bfefSTrond Myklebust #include <linux/rcupdate.h> 521da177e4SLinus Torvalds 533705ad64SJeff Layton #include <trace/events/sunrpc.h> 543705ad64SJeff Layton 5555ae1aabSRicardo Labiaga #include "sunrpc.h" 5655ae1aabSRicardo Labiaga 571da177e4SLinus Torvalds /* 581da177e4SLinus Torvalds * Local variables 591da177e4SLinus Torvalds */ 601da177e4SLinus Torvalds 61f895b252SJeff Layton #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 621da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 631da177e4SLinus Torvalds #endif 641da177e4SLinus Torvalds 651da177e4SLinus Torvalds /* 661da177e4SLinus Torvalds * Local functions 671da177e4SLinus Torvalds */ 6821de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 6937ac86c3SChuck Lever static __be32 xprt_alloc_xid(struct rpc_xprt *xprt); 704e0038b6STrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt); 711da177e4SLinus Torvalds 725ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7381c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7481c098afS\"Talpey, Thomas\ 7512a80469SChuck Lever /** 7681c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 7781c098afS\"Talpey, Thomas\ * @transport: transport to register 7881c098afS\"Talpey, Thomas\ * 7981c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 8081c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 8181c098afS\"Talpey, Thomas\ * 8281c098afS\"Talpey, Thomas\ * Returns: 8381c098afS\"Talpey, Thomas\ * 0: transport successfully registered 8481c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 8581c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 8681c098afS\"Talpey, Thomas\ */ 8781c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 8881c098afS\"Talpey, Thomas\ { 8981c098afS\"Talpey, Thomas\ struct xprt_class *t; 9081c098afS\"Talpey, Thomas\ int result; 9181c098afS\"Talpey, Thomas\ 9281c098afS\"Talpey, Thomas\ result = -EEXIST; 9381c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 9481c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 9581c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 964fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 9781c098afS\"Talpey, Thomas\ goto out; 9881c098afS\"Talpey, Thomas\ } 9981c098afS\"Talpey, Thomas\ 10081c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 10181c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 10281c098afS\"Talpey, Thomas\ transport->name); 10381c098afS\"Talpey, Thomas\ result = 0; 10481c098afS\"Talpey, Thomas\ 10581c098afS\"Talpey, Thomas\ out: 10681c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 10781c098afS\"Talpey, Thomas\ return result; 10881c098afS\"Talpey, Thomas\ } 10981c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 11081c098afS\"Talpey, Thomas\ 11181c098afS\"Talpey, Thomas\ /** 11281c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 11365b6e42cSRandy Dunlap * @transport: transport to unregister 11481c098afS\"Talpey, Thomas\ * 11581c098afS\"Talpey, Thomas\ * Returns: 11681c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 11781c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 11881c098afS\"Talpey, Thomas\ */ 11981c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 12081c098afS\"Talpey, Thomas\ { 12181c098afS\"Talpey, Thomas\ struct xprt_class *t; 12281c098afS\"Talpey, Thomas\ int result; 12381c098afS\"Talpey, Thomas\ 12481c098afS\"Talpey, Thomas\ result = 0; 12581c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 12681c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 12781c098afS\"Talpey, Thomas\ if (t == transport) { 12881c098afS\"Talpey, Thomas\ printk(KERN_INFO 12981c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 13081c098afS\"Talpey, Thomas\ transport->name); 13181c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 13281c098afS\"Talpey, Thomas\ goto out; 13381c098afS\"Talpey, Thomas\ } 13481c098afS\"Talpey, Thomas\ } 13581c098afS\"Talpey, Thomas\ result = -ENOENT; 13681c098afS\"Talpey, Thomas\ 13781c098afS\"Talpey, Thomas\ out: 13881c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 13981c098afS\"Talpey, Thomas\ return result; 14081c098afS\"Talpey, Thomas\ } 14181c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 14281c098afS\"Talpey, Thomas\ 14381c098afS\"Talpey, Thomas\ /** 144441e3e24STom Talpey * xprt_load_transport - load a transport implementation 145441e3e24STom Talpey * @transport_name: transport to load 146441e3e24STom Talpey * 147441e3e24STom Talpey * Returns: 148441e3e24STom Talpey * 0: transport successfully loaded 149441e3e24STom Talpey * -ENOENT: transport module not available 150441e3e24STom Talpey */ 151441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 152441e3e24STom Talpey { 153441e3e24STom Talpey struct xprt_class *t; 154441e3e24STom Talpey int result; 155441e3e24STom Talpey 156441e3e24STom Talpey result = 0; 157441e3e24STom Talpey spin_lock(&xprt_list_lock); 158441e3e24STom Talpey list_for_each_entry(t, &xprt_list, list) { 159441e3e24STom Talpey if (strcmp(t->name, transport_name) == 0) { 160441e3e24STom Talpey spin_unlock(&xprt_list_lock); 161441e3e24STom Talpey goto out; 162441e3e24STom Talpey } 163441e3e24STom Talpey } 164441e3e24STom Talpey spin_unlock(&xprt_list_lock); 165ef7ffe8fSAlex Riesen result = request_module("xprt%s", transport_name); 166441e3e24STom Talpey out: 167441e3e24STom Talpey return result; 168441e3e24STom Talpey } 169441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 170441e3e24STom Talpey 171c544577dSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 172c544577dSTrond Myklebust { 173c544577dSTrond Myklebust xprt->snd_task = NULL; 174c544577dSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 175c544577dSTrond Myklebust smp_mb__before_atomic(); 176c544577dSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 177c544577dSTrond Myklebust smp_mb__after_atomic(); 178c544577dSTrond Myklebust } else 179c544577dSTrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 180c544577dSTrond Myklebust } 181c544577dSTrond Myklebust 182441e3e24STom Talpey /** 18312a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 18412a80469SChuck Lever * @task: task that is requesting access to the transport 185177c27bfSRandy Dunlap * @xprt: pointer to the target transport 18612a80469SChuck Lever * 18712a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 18812a80469SChuck Lever * transport connects from colliding with writes. No congestion control 18912a80469SChuck Lever * is provided. 1901da177e4SLinus Torvalds */ 19143cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 1921da177e4SLinus Torvalds { 19312a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 19412a80469SChuck Lever 19512a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 19612a80469SChuck Lever if (task == xprt->snd_task) 19712a80469SChuck Lever return 1; 19812a80469SChuck Lever goto out_sleep; 19912a80469SChuck Lever } 200c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 201c544577dSTrond Myklebust goto out_unlock; 20212a80469SChuck Lever xprt->snd_task = task; 2034d4a76f3Sj223yang@asset.uwaterloo.ca 20412a80469SChuck Lever return 1; 20512a80469SChuck Lever 206c544577dSTrond Myklebust out_unlock: 207c544577dSTrond Myklebust xprt_clear_locked(xprt); 20812a80469SChuck Lever out_sleep: 20946121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", 21012a80469SChuck Lever task->tk_pid, xprt); 211f05d54ecSTrond Myklebust task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; 21212a80469SChuck Lever task->tk_status = -EAGAIN; 21379c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 21412a80469SChuck Lever return 0; 21512a80469SChuck Lever } 21612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 21712a80469SChuck Lever 21875891f50STrond Myklebust static bool 21975891f50STrond Myklebust xprt_need_congestion_window_wait(struct rpc_xprt *xprt) 22075891f50STrond Myklebust { 22175891f50STrond Myklebust return test_bit(XPRT_CWND_WAIT, &xprt->state); 22275891f50STrond Myklebust } 22375891f50STrond Myklebust 22475891f50STrond Myklebust static void 22575891f50STrond Myklebust xprt_set_congestion_window_wait(struct rpc_xprt *xprt) 22675891f50STrond Myklebust { 22775891f50STrond Myklebust if (!list_empty(&xprt->xmit_queue)) { 22875891f50STrond Myklebust /* Peek at head of queue to see if it can make progress */ 22975891f50STrond Myklebust if (list_first_entry(&xprt->xmit_queue, struct rpc_rqst, 23075891f50STrond Myklebust rq_xmit)->rq_cong) 23175891f50STrond Myklebust return; 23275891f50STrond Myklebust } 23375891f50STrond Myklebust set_bit(XPRT_CWND_WAIT, &xprt->state); 23475891f50STrond Myklebust } 23575891f50STrond Myklebust 23675891f50STrond Myklebust static void 23775891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(struct rpc_xprt *xprt) 23875891f50STrond Myklebust { 23975891f50STrond Myklebust if (!RPCXPRT_CONGESTED(xprt)) 24075891f50STrond Myklebust clear_bit(XPRT_CWND_WAIT, &xprt->state); 24175891f50STrond Myklebust } 24275891f50STrond Myklebust 24312a80469SChuck Lever /* 24412a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 24512a80469SChuck Lever * @task: task that is requesting access to the transport 24612a80469SChuck Lever * 24712a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 24812a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 24912a80469SChuck Lever * woken up and given access to the transport. 25075891f50STrond Myklebust * Note that the lock is only granted if we know there are free slots. 25112a80469SChuck Lever */ 25243cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 25312a80469SChuck Lever { 2541da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 2551da177e4SLinus Torvalds 2562226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2571da177e4SLinus Torvalds if (task == xprt->snd_task) 2581da177e4SLinus Torvalds return 1; 2591da177e4SLinus Torvalds goto out_sleep; 2601da177e4SLinus Torvalds } 26143cedbf0STrond Myklebust if (req == NULL) { 26243cedbf0STrond Myklebust xprt->snd_task = task; 26343cedbf0STrond Myklebust return 1; 26443cedbf0STrond Myklebust } 265c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 266c544577dSTrond Myklebust goto out_unlock; 26775891f50STrond Myklebust if (!xprt_need_congestion_window_wait(xprt)) { 2681da177e4SLinus Torvalds xprt->snd_task = task; 2691da177e4SLinus Torvalds return 1; 2701da177e4SLinus Torvalds } 271c544577dSTrond Myklebust out_unlock: 272632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2731da177e4SLinus Torvalds out_sleep: 27446121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 275f05d54ecSTrond Myklebust task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; 2761da177e4SLinus Torvalds task->tk_status = -EAGAIN; 27779c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 2781da177e4SLinus Torvalds return 0; 2791da177e4SLinus Torvalds } 28012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2811da177e4SLinus Torvalds 28212a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2831da177e4SLinus Torvalds { 2841da177e4SLinus Torvalds int retval; 2851da177e4SLinus Torvalds 286bd79bc57STrond Myklebust if (test_bit(XPRT_LOCKED, &xprt->state) && xprt->snd_task == task) 287bd79bc57STrond Myklebust return 1; 2884a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 28943cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 2904a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2911da177e4SLinus Torvalds return retval; 2921da177e4SLinus Torvalds } 2931da177e4SLinus Torvalds 294961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 2951da177e4SLinus Torvalds { 296961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 29749e9a890SChuck Lever 29849e9a890SChuck Lever xprt->snd_task = task; 299961a828dSTrond Myklebust return true; 300961a828dSTrond Myklebust } 301961a828dSTrond Myklebust 302961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 303961a828dSTrond Myklebust { 304961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 30549e9a890SChuck Lever return; 306c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 307c544577dSTrond Myklebust goto out_unlock; 308f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 309f1dc237cSTrond Myklebust __xprt_lock_write_func, xprt)) 310961a828dSTrond Myklebust return; 311c544577dSTrond Myklebust out_unlock: 312632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 31349e9a890SChuck Lever } 31449e9a890SChuck Lever 315961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 316961a828dSTrond Myklebust { 317961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 318961a828dSTrond Myklebust return; 319c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 320c544577dSTrond Myklebust goto out_unlock; 32175891f50STrond Myklebust if (xprt_need_congestion_window_wait(xprt)) 322961a828dSTrond Myklebust goto out_unlock; 323f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 32475891f50STrond Myklebust __xprt_lock_write_func, xprt)) 325961a828dSTrond Myklebust return; 3261da177e4SLinus Torvalds out_unlock: 327632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3281da177e4SLinus Torvalds } 3291da177e4SLinus Torvalds 33049e9a890SChuck Lever /** 33149e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 33249e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 33349e9a890SChuck Lever * @task: task that is releasing access to the transport 33449e9a890SChuck Lever * 33549e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 3361da177e4SLinus Torvalds */ 33749e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3381da177e4SLinus Torvalds { 3391da177e4SLinus Torvalds if (xprt->snd_task == task) { 340632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3411da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3421da177e4SLinus Torvalds } 3431da177e4SLinus Torvalds } 34412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3451da177e4SLinus Torvalds 34649e9a890SChuck Lever /** 34749e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 34849e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 34949e9a890SChuck Lever * @task: task that is releasing access to the transport 35049e9a890SChuck Lever * 35149e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 35249e9a890SChuck Lever * transport if the transport's congestion window allows it. 35349e9a890SChuck Lever */ 35449e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 35549e9a890SChuck Lever { 35649e9a890SChuck Lever if (xprt->snd_task == task) { 357632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 35849e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 35949e9a890SChuck Lever } 36049e9a890SChuck Lever } 36112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 36249e9a890SChuck Lever 36349e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3641da177e4SLinus Torvalds { 365bd79bc57STrond Myklebust if (xprt->snd_task != task) 366bd79bc57STrond Myklebust return; 3674a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 36849e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3694a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3701da177e4SLinus Torvalds } 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds /* 3731da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3741da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3751da177e4SLinus Torvalds */ 3761da177e4SLinus Torvalds static int 37775891f50STrond Myklebust __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 3781da177e4SLinus Torvalds { 3791da177e4SLinus Torvalds if (req->rq_cong) 3801da177e4SLinus Torvalds return 1; 38146121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 38275891f50STrond Myklebust req->rq_task->tk_pid, xprt->cong, xprt->cwnd); 38375891f50STrond Myklebust if (RPCXPRT_CONGESTED(xprt)) { 38475891f50STrond Myklebust xprt_set_congestion_window_wait(xprt); 3851da177e4SLinus Torvalds return 0; 38675891f50STrond Myklebust } 3871da177e4SLinus Torvalds req->rq_cong = 1; 3881da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 3891da177e4SLinus Torvalds return 1; 3901da177e4SLinus Torvalds } 3911da177e4SLinus Torvalds 3921da177e4SLinus Torvalds /* 3931da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 3941da177e4SLinus Torvalds * that has been sleeping due to congestion 3951da177e4SLinus Torvalds */ 3961da177e4SLinus Torvalds static void 3971da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 3981da177e4SLinus Torvalds { 3991da177e4SLinus Torvalds if (!req->rq_cong) 4001da177e4SLinus Torvalds return; 4011da177e4SLinus Torvalds req->rq_cong = 0; 4021da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 40375891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(xprt); 40449e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4051da177e4SLinus Torvalds } 4061da177e4SLinus Torvalds 40746c0ee8bSChuck Lever /** 40875891f50STrond Myklebust * xprt_request_get_cong - Request congestion control credits 40975891f50STrond Myklebust * @xprt: pointer to transport 41075891f50STrond Myklebust * @req: pointer to RPC request 41175891f50STrond Myklebust * 41275891f50STrond Myklebust * Useful for transports that require congestion control. 41375891f50STrond Myklebust */ 41475891f50STrond Myklebust bool 41575891f50STrond Myklebust xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 41675891f50STrond Myklebust { 41775891f50STrond Myklebust bool ret = false; 41875891f50STrond Myklebust 41975891f50STrond Myklebust if (req->rq_cong) 42075891f50STrond Myklebust return true; 42175891f50STrond Myklebust spin_lock_bh(&xprt->transport_lock); 42275891f50STrond Myklebust ret = __xprt_get_cong(xprt, req) != 0; 42375891f50STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 42475891f50STrond Myklebust return ret; 42575891f50STrond Myklebust } 42675891f50STrond Myklebust EXPORT_SYMBOL_GPL(xprt_request_get_cong); 42775891f50STrond Myklebust 42875891f50STrond Myklebust /** 429a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 430a58dd398SChuck Lever * @task: RPC request that recently completed 431a58dd398SChuck Lever * 432a58dd398SChuck Lever * Useful for transports that require congestion control. 433a58dd398SChuck Lever */ 434a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 435a58dd398SChuck Lever { 436a4f0835cSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 437a4f0835cSTrond Myklebust 438a4f0835cSTrond Myklebust __xprt_put_cong(req->rq_xprt, req); 439a58dd398SChuck Lever } 44012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 441a58dd398SChuck Lever 44275891f50STrond Myklebust /* 44375891f50STrond Myklebust * Clear the congestion window wait flag and wake up the next 44475891f50STrond Myklebust * entry on xprt->sending 44575891f50STrond Myklebust */ 44675891f50STrond Myklebust static void 44775891f50STrond Myklebust xprt_clear_congestion_window_wait(struct rpc_xprt *xprt) 44875891f50STrond Myklebust { 44975891f50STrond Myklebust if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) { 45075891f50STrond Myklebust spin_lock_bh(&xprt->transport_lock); 45175891f50STrond Myklebust __xprt_lock_write_next_cong(xprt); 45275891f50STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 45375891f50STrond Myklebust } 45475891f50STrond Myklebust } 45575891f50STrond Myklebust 456a58dd398SChuck Lever /** 45746c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 4586a24dfb6STrond Myklebust * @xprt: pointer to xprt 45946c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 46046c0ee8bSChuck Lever * @result: result code of completed RPC request 46146c0ee8bSChuck Lever * 4624f4cf5adSChuck Lever * The transport code maintains an estimate on the maximum number of out- 4634f4cf5adSChuck Lever * standing RPC requests, using a smoothed version of the congestion 4644f4cf5adSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 4654f4cf5adSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 4664f4cf5adSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 4674f4cf5adSChuck Lever * 4684f4cf5adSChuck Lever * - a reply is received and 4694f4cf5adSChuck Lever * - a full number of requests are outstanding and 4704f4cf5adSChuck Lever * - the congestion window hasn't been updated recently. 4711da177e4SLinus Torvalds */ 4726a24dfb6STrond Myklebust void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) 4731da177e4SLinus Torvalds { 47446c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 47546c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4761da177e4SLinus Torvalds 4771da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4781da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4791da177e4SLinus Torvalds * the result gets rounded properly. */ 4801da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4811da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4821da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 48349e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4841da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4851da177e4SLinus Torvalds cwnd >>= 1; 4861da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4871da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4881da177e4SLinus Torvalds } 4891da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4901da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4911da177e4SLinus Torvalds xprt->cwnd = cwnd; 49246c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4931da177e4SLinus Torvalds } 49412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4951da177e4SLinus Torvalds 49644fbac22SChuck Lever /** 49744fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 49844fbac22SChuck Lever * @xprt: transport with waiting tasks 49944fbac22SChuck Lever * @status: result code to plant in each task before waking it 50044fbac22SChuck Lever * 50144fbac22SChuck Lever */ 50244fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 50344fbac22SChuck Lever { 50444fbac22SChuck Lever if (status < 0) 50544fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 50644fbac22SChuck Lever else 50744fbac22SChuck Lever rpc_wake_up(&xprt->pending); 50844fbac22SChuck Lever } 50912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 51044fbac22SChuck Lever 511c7b2cae8SChuck Lever /** 512c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 513c544577dSTrond Myklebust * @xprt: transport 514a9a6b52eSTrond Myklebust * 515a9a6b52eSTrond Myklebust * Note that we only set the timer for the case of RPC_IS_SOFT(), since 516a9a6b52eSTrond Myklebust * we don't in general want to force a socket disconnection due to 517a9a6b52eSTrond Myklebust * an incomplete RPC call transmission. 518c7b2cae8SChuck Lever */ 519c544577dSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_xprt *xprt) 520c7b2cae8SChuck Lever { 521c544577dSTrond Myklebust set_bit(XPRT_WRITE_SPACE, &xprt->state); 522c7b2cae8SChuck Lever } 52312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 524c7b2cae8SChuck Lever 525c544577dSTrond Myklebust static bool 526c544577dSTrond Myklebust xprt_clear_write_space_locked(struct rpc_xprt *xprt) 527c544577dSTrond Myklebust { 528c544577dSTrond Myklebust if (test_and_clear_bit(XPRT_WRITE_SPACE, &xprt->state)) { 529c544577dSTrond Myklebust __xprt_lock_write_next(xprt); 530c544577dSTrond Myklebust dprintk("RPC: write space: waking waiting task on " 531c544577dSTrond Myklebust "xprt %p\n", xprt); 532c544577dSTrond Myklebust return true; 533c544577dSTrond Myklebust } 534c544577dSTrond Myklebust return false; 535c544577dSTrond Myklebust } 536c544577dSTrond Myklebust 537c7b2cae8SChuck Lever /** 538c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 539c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 540c7b2cae8SChuck Lever * 541c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 542c7b2cae8SChuck Lever */ 543c544577dSTrond Myklebust bool xprt_write_space(struct rpc_xprt *xprt) 544c7b2cae8SChuck Lever { 545c544577dSTrond Myklebust bool ret; 546c544577dSTrond Myklebust 547c544577dSTrond Myklebust if (!test_bit(XPRT_WRITE_SPACE, &xprt->state)) 548c544577dSTrond Myklebust return false; 549c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 550c544577dSTrond Myklebust ret = xprt_clear_write_space_locked(xprt); 551c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 552c544577dSTrond Myklebust return ret; 553c7b2cae8SChuck Lever } 55412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 555c7b2cae8SChuck Lever 556fe3aca29SChuck Lever /** 557fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 558fe3aca29SChuck Lever * @task: task whose timeout is to be set 559fe3aca29SChuck Lever * 560fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 561fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 562fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 563fe3aca29SChuck Lever */ 564fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 565fe3aca29SChuck Lever { 566fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 567fe3aca29SChuck Lever } 56812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 569fe3aca29SChuck Lever 5702c53040fSBen Hutchings /** 571fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout 572fe3aca29SChuck Lever * @task: task whose timeout is to be set 573fe3aca29SChuck Lever * 574fe3aca29SChuck Lever * Set a request's retransmit timeout using the RTT estimator. 575fe3aca29SChuck Lever */ 576fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 577fe3aca29SChuck Lever { 578fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 579ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 580ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 581fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 582ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 583fe3aca29SChuck Lever 584fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 585fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 586fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 587fe3aca29SChuck Lever task->tk_timeout = max_timeout; 588fe3aca29SChuck Lever } 58912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 590fe3aca29SChuck Lever 5911da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5921da177e4SLinus Torvalds { 593ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5941da177e4SLinus Torvalds 5951da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5961da177e4SLinus Torvalds if (to->to_exponential) 5971da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5981da177e4SLinus Torvalds else 5991da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 6001da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 6011da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 6021da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 6031da177e4SLinus Torvalds } 6041da177e4SLinus Torvalds 6059903cd1cSChuck Lever /** 6069903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 6079903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 6089903cd1cSChuck Lever * 6091da177e4SLinus Torvalds */ 6101da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 6111da177e4SLinus Torvalds { 6121da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 613ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 6141da177e4SLinus Torvalds int status = 0; 6151da177e4SLinus Torvalds 6161da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 6171da177e4SLinus Torvalds if (to->to_exponential) 6181da177e4SLinus Torvalds req->rq_timeout <<= 1; 6191da177e4SLinus Torvalds else 6201da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 6211da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 6221da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 6231da177e4SLinus Torvalds req->rq_retries++; 6241da177e4SLinus Torvalds } else { 6251da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 6261da177e4SLinus Torvalds req->rq_retries = 0; 6271da177e4SLinus Torvalds xprt_reset_majortimeo(req); 6281da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 6294a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6301da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 6314a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6321da177e4SLinus Torvalds status = -ETIMEDOUT; 6331da177e4SLinus Torvalds } 6341da177e4SLinus Torvalds 6351da177e4SLinus Torvalds if (req->rq_timeout == 0) { 6361da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 6371da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 6381da177e4SLinus Torvalds } 6391da177e4SLinus Torvalds return status; 6401da177e4SLinus Torvalds } 6411da177e4SLinus Torvalds 64265f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 6431da177e4SLinus Torvalds { 64465f27f38SDavid Howells struct rpc_xprt *xprt = 64565f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 6461da177e4SLinus Torvalds 64766af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 6484876cc77STrond Myklebust xprt->ops->close(xprt); 6491da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 65079234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 6511da177e4SLinus Torvalds } 6521da177e4SLinus Torvalds 6539903cd1cSChuck Lever /** 65462da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6559903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6569903cd1cSChuck Lever * 6571da177e4SLinus Torvalds */ 65862da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6591da177e4SLinus Torvalds { 6601da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6614a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6621da177e4SLinus Torvalds xprt_clear_connected(xprt); 663c544577dSTrond Myklebust xprt_clear_write_space_locked(xprt); 6642a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6654a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6661da177e4SLinus Torvalds } 66762da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6681da177e4SLinus Torvalds 66966af1e55STrond Myklebust /** 67066af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 67166af1e55STrond Myklebust * @xprt: transport to disconnect 67266af1e55STrond Myklebust * 67366af1e55STrond Myklebust */ 67466af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 67566af1e55STrond Myklebust { 67666af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 67766af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 67866af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 67966af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 68066af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 68140a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 6820445f92cSTrond Myklebust else if (xprt->snd_task) 6830445f92cSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 6840445f92cSTrond Myklebust xprt->snd_task, -ENOTCONN); 68566af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 68666af1e55STrond Myklebust } 687e2a4f4fbSChuck Lever EXPORT_SYMBOL_GPL(xprt_force_disconnect); 68866af1e55STrond Myklebust 6897f3a1d1eSTrond Myklebust static unsigned int 6907f3a1d1eSTrond Myklebust xprt_connect_cookie(struct rpc_xprt *xprt) 6917f3a1d1eSTrond Myklebust { 6927f3a1d1eSTrond Myklebust return READ_ONCE(xprt->connect_cookie); 6937f3a1d1eSTrond Myklebust } 6947f3a1d1eSTrond Myklebust 6957f3a1d1eSTrond Myklebust static bool 6967f3a1d1eSTrond Myklebust xprt_request_retransmit_after_disconnect(struct rpc_task *task) 6977f3a1d1eSTrond Myklebust { 6987f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 6997f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 7007f3a1d1eSTrond Myklebust 7017f3a1d1eSTrond Myklebust return req->rq_connect_cookie != xprt_connect_cookie(xprt) || 7027f3a1d1eSTrond Myklebust !xprt_connected(xprt); 7037f3a1d1eSTrond Myklebust } 7047f3a1d1eSTrond Myklebust 7057c1d71cfSTrond Myklebust /** 7067c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 7077c1d71cfSTrond Myklebust * @xprt: transport to disconnect 7087c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 7097c1d71cfSTrond Myklebust * 7107c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 7117c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 7127c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 7137c1d71cfSTrond Myklebust * a batch of RPC requests. 7147c1d71cfSTrond Myklebust * 7157c1d71cfSTrond Myklebust */ 7167c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 7177c1d71cfSTrond Myklebust { 7187c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 7197c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 7207c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 7217c1d71cfSTrond Myklebust goto out; 7222c2ee6d2SNeilBrown if (test_bit(XPRT_CLOSING, &xprt->state)) 7237c1d71cfSTrond Myklebust goto out; 7247c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 7257c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 7267c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 72740a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 7282a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 7297c1d71cfSTrond Myklebust out: 7307c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 7317c1d71cfSTrond Myklebust } 7327c1d71cfSTrond Myklebust 733ad3331acSTrond Myklebust static bool 734ad3331acSTrond Myklebust xprt_has_timer(const struct rpc_xprt *xprt) 735ad3331acSTrond Myklebust { 736ad3331acSTrond Myklebust return xprt->idle_timeout != 0; 737ad3331acSTrond Myklebust } 738ad3331acSTrond Myklebust 739ad3331acSTrond Myklebust static void 740ad3331acSTrond Myklebust xprt_schedule_autodisconnect(struct rpc_xprt *xprt) 741ad3331acSTrond Myklebust __must_hold(&xprt->transport_lock) 742ad3331acSTrond Myklebust { 74395f7691dSTrond Myklebust if (RB_EMPTY_ROOT(&xprt->recv_queue) && xprt_has_timer(xprt)) 744ad3331acSTrond Myklebust mod_timer(&xprt->timer, xprt->last_used + xprt->idle_timeout); 745ad3331acSTrond Myklebust } 746ad3331acSTrond Myklebust 7471da177e4SLinus Torvalds static void 748ff861c4dSKees Cook xprt_init_autodisconnect(struct timer_list *t) 7491da177e4SLinus Torvalds { 750ff861c4dSKees Cook struct rpc_xprt *xprt = from_timer(xprt, t, timer); 7511da177e4SLinus Torvalds 7524a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 75395f7691dSTrond Myklebust if (!RB_EMPTY_ROOT(&xprt->recv_queue)) 7541da177e4SLinus Torvalds goto out_abort; 755ad3331acSTrond Myklebust /* Reset xprt->last_used to avoid connect/autodisconnect cycling */ 756ad3331acSTrond Myklebust xprt->last_used = jiffies; 7572226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 7581da177e4SLinus Torvalds goto out_abort; 7594a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 76040a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 7611da177e4SLinus Torvalds return; 7621da177e4SLinus Torvalds out_abort: 7634a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 7641da177e4SLinus Torvalds } 7651da177e4SLinus Torvalds 766718ba5b8STrond Myklebust bool xprt_lock_connect(struct rpc_xprt *xprt, 767718ba5b8STrond Myklebust struct rpc_task *task, 768718ba5b8STrond Myklebust void *cookie) 769718ba5b8STrond Myklebust { 770718ba5b8STrond Myklebust bool ret = false; 771718ba5b8STrond Myklebust 772718ba5b8STrond Myklebust spin_lock_bh(&xprt->transport_lock); 773718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 774718ba5b8STrond Myklebust goto out; 775718ba5b8STrond Myklebust if (xprt->snd_task != task) 776718ba5b8STrond Myklebust goto out; 777718ba5b8STrond Myklebust xprt->snd_task = cookie; 778718ba5b8STrond Myklebust ret = true; 779718ba5b8STrond Myklebust out: 780718ba5b8STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 781718ba5b8STrond Myklebust return ret; 782718ba5b8STrond Myklebust } 783718ba5b8STrond Myklebust 784718ba5b8STrond Myklebust void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) 785718ba5b8STrond Myklebust { 786718ba5b8STrond Myklebust spin_lock_bh(&xprt->transport_lock); 787718ba5b8STrond Myklebust if (xprt->snd_task != cookie) 788718ba5b8STrond Myklebust goto out; 789718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 790718ba5b8STrond Myklebust goto out; 791718ba5b8STrond Myklebust xprt->snd_task =NULL; 792718ba5b8STrond Myklebust xprt->ops->release_xprt(xprt, NULL); 793ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 794718ba5b8STrond Myklebust out: 795718ba5b8STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 79679234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 797718ba5b8STrond Myklebust } 798718ba5b8STrond Myklebust 7999903cd1cSChuck Lever /** 8009903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 8019903cd1cSChuck Lever * @task: RPC task that is requesting the connect 8021da177e4SLinus Torvalds * 8031da177e4SLinus Torvalds */ 8041da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 8051da177e4SLinus Torvalds { 806ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 8071da177e4SLinus Torvalds 80846121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 8091da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 8101da177e4SLinus Torvalds 811ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 81201d37c42STrond Myklebust task->tk_status = -EAGAIN; 8131da177e4SLinus Torvalds return; 8141da177e4SLinus Torvalds } 8151da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 8161da177e4SLinus Torvalds return; 817feb8ca37STrond Myklebust 818feb8ca37STrond Myklebust if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) 819feb8ca37STrond Myklebust xprt->ops->close(xprt); 820feb8ca37STrond Myklebust 821718ba5b8STrond Myklebust if (!xprt_connected(xprt)) { 822a8ce4a8fSTrond Myklebust task->tk_timeout = task->tk_rqstp->rq_timeout; 8232c2ee6d2SNeilBrown task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie; 824abc13275STrond Myklebust rpc_sleep_on(&xprt->pending, task, NULL); 8250b9e7943STrond Myklebust 8260b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 8270b9e7943STrond Myklebust return; 8280b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 8290b9e7943STrond Myklebust return; 8300a9a4304STrond Myklebust /* Race breaker */ 8310a9a4304STrond Myklebust if (!xprt_connected(xprt)) { 832262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 8331b092092STrond Myklebust xprt->ops->connect(xprt, task); 8340a9a4304STrond Myklebust } else { 8350a9a4304STrond Myklebust xprt_clear_connecting(xprt); 8360a9a4304STrond Myklebust task->tk_status = 0; 8370a9a4304STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 8380a9a4304STrond Myklebust } 8391da177e4SLinus Torvalds } 840718ba5b8STrond Myklebust xprt_release_write(xprt, task); 8411da177e4SLinus Torvalds } 8421da177e4SLinus Torvalds 84395f7691dSTrond Myklebust enum xprt_xid_rb_cmp { 84495f7691dSTrond Myklebust XID_RB_EQUAL, 84595f7691dSTrond Myklebust XID_RB_LEFT, 84695f7691dSTrond Myklebust XID_RB_RIGHT, 84795f7691dSTrond Myklebust }; 84895f7691dSTrond Myklebust static enum xprt_xid_rb_cmp 84995f7691dSTrond Myklebust xprt_xid_cmp(__be32 xid1, __be32 xid2) 85095f7691dSTrond Myklebust { 85195f7691dSTrond Myklebust if (xid1 == xid2) 85295f7691dSTrond Myklebust return XID_RB_EQUAL; 85395f7691dSTrond Myklebust if ((__force u32)xid1 < (__force u32)xid2) 85495f7691dSTrond Myklebust return XID_RB_LEFT; 85595f7691dSTrond Myklebust return XID_RB_RIGHT; 85695f7691dSTrond Myklebust } 85795f7691dSTrond Myklebust 85895f7691dSTrond Myklebust static struct rpc_rqst * 85995f7691dSTrond Myklebust xprt_request_rb_find(struct rpc_xprt *xprt, __be32 xid) 86095f7691dSTrond Myklebust { 86195f7691dSTrond Myklebust struct rb_node *n = xprt->recv_queue.rb_node; 86295f7691dSTrond Myklebust struct rpc_rqst *req; 86395f7691dSTrond Myklebust 86495f7691dSTrond Myklebust while (n != NULL) { 86595f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 86695f7691dSTrond Myklebust switch (xprt_xid_cmp(xid, req->rq_xid)) { 86795f7691dSTrond Myklebust case XID_RB_LEFT: 86895f7691dSTrond Myklebust n = n->rb_left; 86995f7691dSTrond Myklebust break; 87095f7691dSTrond Myklebust case XID_RB_RIGHT: 87195f7691dSTrond Myklebust n = n->rb_right; 87295f7691dSTrond Myklebust break; 87395f7691dSTrond Myklebust case XID_RB_EQUAL: 87495f7691dSTrond Myklebust return req; 87595f7691dSTrond Myklebust } 87695f7691dSTrond Myklebust } 87795f7691dSTrond Myklebust return NULL; 87895f7691dSTrond Myklebust } 87995f7691dSTrond Myklebust 88095f7691dSTrond Myklebust static void 88195f7691dSTrond Myklebust xprt_request_rb_insert(struct rpc_xprt *xprt, struct rpc_rqst *new) 88295f7691dSTrond Myklebust { 88395f7691dSTrond Myklebust struct rb_node **p = &xprt->recv_queue.rb_node; 88495f7691dSTrond Myklebust struct rb_node *n = NULL; 88595f7691dSTrond Myklebust struct rpc_rqst *req; 88695f7691dSTrond Myklebust 88795f7691dSTrond Myklebust while (*p != NULL) { 88895f7691dSTrond Myklebust n = *p; 88995f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 89095f7691dSTrond Myklebust switch(xprt_xid_cmp(new->rq_xid, req->rq_xid)) { 89195f7691dSTrond Myklebust case XID_RB_LEFT: 89295f7691dSTrond Myklebust p = &n->rb_left; 89395f7691dSTrond Myklebust break; 89495f7691dSTrond Myklebust case XID_RB_RIGHT: 89595f7691dSTrond Myklebust p = &n->rb_right; 89695f7691dSTrond Myklebust break; 89795f7691dSTrond Myklebust case XID_RB_EQUAL: 89895f7691dSTrond Myklebust WARN_ON_ONCE(new != req); 89995f7691dSTrond Myklebust return; 90095f7691dSTrond Myklebust } 90195f7691dSTrond Myklebust } 90295f7691dSTrond Myklebust rb_link_node(&new->rq_recv, n, p); 90395f7691dSTrond Myklebust rb_insert_color(&new->rq_recv, &xprt->recv_queue); 90495f7691dSTrond Myklebust } 90595f7691dSTrond Myklebust 90695f7691dSTrond Myklebust static void 90795f7691dSTrond Myklebust xprt_request_rb_remove(struct rpc_xprt *xprt, struct rpc_rqst *req) 90895f7691dSTrond Myklebust { 90995f7691dSTrond Myklebust rb_erase(&req->rq_recv, &xprt->recv_queue); 91095f7691dSTrond Myklebust } 91195f7691dSTrond Myklebust 9129903cd1cSChuck Lever /** 9139903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 9149903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 9159903cd1cSChuck Lever * @xid: RPC XID of incoming reply 9169903cd1cSChuck Lever * 91775c84151STrond Myklebust * Caller holds xprt->queue_lock. 9181da177e4SLinus Torvalds */ 919d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 9201da177e4SLinus Torvalds { 9218f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 9221da177e4SLinus Torvalds 92395f7691dSTrond Myklebust entry = xprt_request_rb_find(xprt, xid); 92495f7691dSTrond Myklebust if (entry != NULL) { 9253705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, 0); 9260b87a46bSChuck Lever entry->rq_rtt = ktime_sub(ktime_get(), entry->rq_xtime); 927262ca07dSChuck Lever return entry; 9283705ad64SJeff Layton } 92946121cf7SChuck Lever 93046121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 93146121cf7SChuck Lever ntohl(xid)); 9323705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, -ENOENT); 933262ca07dSChuck Lever xprt->stat.bad_xids++; 934262ca07dSChuck Lever return NULL; 9351da177e4SLinus Torvalds } 93612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 9371da177e4SLinus Torvalds 938cf9946cdSTrond Myklebust static bool 939cf9946cdSTrond Myklebust xprt_is_pinned_rqst(struct rpc_rqst *req) 940cf9946cdSTrond Myklebust { 941cf9946cdSTrond Myklebust return atomic_read(&req->rq_pin) != 0; 942cf9946cdSTrond Myklebust } 943cf9946cdSTrond Myklebust 944729749bbSTrond Myklebust /** 945729749bbSTrond Myklebust * xprt_pin_rqst - Pin a request on the transport receive list 946729749bbSTrond Myklebust * @req: Request to pin 947729749bbSTrond Myklebust * 948729749bbSTrond Myklebust * Caller must ensure this is atomic with the call to xprt_lookup_rqst() 949cf9946cdSTrond Myklebust * so should be holding the xprt receive lock. 950729749bbSTrond Myklebust */ 951729749bbSTrond Myklebust void xprt_pin_rqst(struct rpc_rqst *req) 952729749bbSTrond Myklebust { 953cf9946cdSTrond Myklebust atomic_inc(&req->rq_pin); 954729749bbSTrond Myklebust } 9559590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_pin_rqst); 956729749bbSTrond Myklebust 957729749bbSTrond Myklebust /** 958729749bbSTrond Myklebust * xprt_unpin_rqst - Unpin a request on the transport receive list 959729749bbSTrond Myklebust * @req: Request to pin 960729749bbSTrond Myklebust * 961cf9946cdSTrond Myklebust * Caller should be holding the xprt receive lock. 962729749bbSTrond Myklebust */ 963729749bbSTrond Myklebust void xprt_unpin_rqst(struct rpc_rqst *req) 964729749bbSTrond Myklebust { 965cf9946cdSTrond Myklebust if (!test_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate)) { 966cf9946cdSTrond Myklebust atomic_dec(&req->rq_pin); 967cf9946cdSTrond Myklebust return; 968cf9946cdSTrond Myklebust } 969cf9946cdSTrond Myklebust if (atomic_dec_and_test(&req->rq_pin)) 970cf9946cdSTrond Myklebust wake_up_var(&req->rq_pin); 971729749bbSTrond Myklebust } 9729590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_unpin_rqst); 973729749bbSTrond Myklebust 974729749bbSTrond Myklebust static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) 975729749bbSTrond Myklebust { 976cf9946cdSTrond Myklebust wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); 977729749bbSTrond Myklebust } 978729749bbSTrond Myklebust 979edc81dcdSTrond Myklebust static bool 980edc81dcdSTrond Myklebust xprt_request_data_received(struct rpc_task *task) 981edc81dcdSTrond Myklebust { 982edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 983edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; 984edc81dcdSTrond Myklebust } 985edc81dcdSTrond Myklebust 986edc81dcdSTrond Myklebust static bool 987edc81dcdSTrond Myklebust xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst *req) 988edc81dcdSTrond Myklebust { 989edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 990edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) == 0; 991edc81dcdSTrond Myklebust } 992edc81dcdSTrond Myklebust 993edc81dcdSTrond Myklebust /** 994edc81dcdSTrond Myklebust * xprt_request_enqueue_receive - Add an request to the receive queue 995edc81dcdSTrond Myklebust * @task: RPC task 996edc81dcdSTrond Myklebust * 997edc81dcdSTrond Myklebust */ 998edc81dcdSTrond Myklebust void 999edc81dcdSTrond Myklebust xprt_request_enqueue_receive(struct rpc_task *task) 1000edc81dcdSTrond Myklebust { 1001edc81dcdSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1002edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1003edc81dcdSTrond Myklebust 1004edc81dcdSTrond Myklebust if (!xprt_request_need_enqueue_receive(task, req)) 1005edc81dcdSTrond Myklebust return; 1006edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1007edc81dcdSTrond Myklebust 1008edc81dcdSTrond Myklebust /* Update the softirq receive buffer */ 1009edc81dcdSTrond Myklebust memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 1010edc81dcdSTrond Myklebust sizeof(req->rq_private_buf)); 1011edc81dcdSTrond Myklebust 1012edc81dcdSTrond Myklebust /* Add request to the receive list */ 101395f7691dSTrond Myklebust xprt_request_rb_insert(xprt, req); 1014edc81dcdSTrond Myklebust set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); 1015edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1016edc81dcdSTrond Myklebust 1017edc81dcdSTrond Myklebust xprt_reset_majortimeo(req); 1018edc81dcdSTrond Myklebust /* Turn off autodisconnect */ 1019edc81dcdSTrond Myklebust del_singleshot_timer_sync(&xprt->timer); 1020edc81dcdSTrond Myklebust } 1021edc81dcdSTrond Myklebust 1022edc81dcdSTrond Myklebust /** 1023edc81dcdSTrond Myklebust * xprt_request_dequeue_receive_locked - Remove a request from the receive queue 1024edc81dcdSTrond Myklebust * @task: RPC task 1025edc81dcdSTrond Myklebust * 1026edc81dcdSTrond Myklebust * Caller must hold xprt->queue_lock. 1027edc81dcdSTrond Myklebust */ 1028edc81dcdSTrond Myklebust static void 1029edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(struct rpc_task *task) 1030edc81dcdSTrond Myklebust { 103195f7691dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 103295f7691dSTrond Myklebust 1033edc81dcdSTrond Myklebust if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 103495f7691dSTrond Myklebust xprt_request_rb_remove(req->rq_xprt, req); 1035edc81dcdSTrond Myklebust } 1036edc81dcdSTrond Myklebust 1037ecd465eeSChuck Lever /** 1038ecd465eeSChuck Lever * xprt_update_rtt - Update RPC RTT statistics 1039ecd465eeSChuck Lever * @task: RPC request that recently completed 1040ecd465eeSChuck Lever * 104175c84151STrond Myklebust * Caller holds xprt->queue_lock. 1042ecd465eeSChuck Lever */ 1043ecd465eeSChuck Lever void xprt_update_rtt(struct rpc_task *task) 10441da177e4SLinus Torvalds { 10451570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 10461570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 104795c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 1048d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 10491570c1e4SChuck Lever 10501da177e4SLinus Torvalds if (timer) { 10511da177e4SLinus Torvalds if (req->rq_ntrans == 1) 1052ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 10531570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 10541da177e4SLinus Torvalds } 10551da177e4SLinus Torvalds } 1056ecd465eeSChuck Lever EXPORT_SYMBOL_GPL(xprt_update_rtt); 10571da177e4SLinus Torvalds 10581570c1e4SChuck Lever /** 10591570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 10601570c1e4SChuck Lever * @task: RPC request that recently completed 10611570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 10621570c1e4SChuck Lever * 106375c84151STrond Myklebust * Caller holds xprt->queue_lock. 10641570c1e4SChuck Lever */ 10651570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 10661570c1e4SChuck Lever { 10671570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 1068fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 10691da177e4SLinus Torvalds 10701570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 10711570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 10723705ad64SJeff Layton trace_xprt_complete_rqst(xprt, req->rq_xid, copied); 10731da177e4SLinus Torvalds 1074fda13939STrond Myklebust xprt->stat.recvs++; 1075ef759a2eSChuck Lever 10761e799b67STrond Myklebust req->rq_private_buf.len = copied; 1077dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 1078dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 107943ac3f29STrond Myklebust smp_wmb(); 1080dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 1081edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 1082fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 10831da177e4SLinus Torvalds } 108412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 10851da177e4SLinus Torvalds 108646c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 10871da177e4SLinus Torvalds { 10881da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 10891da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 10901da177e4SLinus Torvalds 10915d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 10925d00837bSTrond Myklebust return; 109346c0ee8bSChuck Lever 109482476d9fSChuck Lever trace_xprt_timer(xprt, req->rq_xid, task->tk_status); 1095dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 109646c0ee8bSChuck Lever if (xprt->ops->timer) 10976a24dfb6STrond Myklebust xprt->ops->timer(xprt, task); 10985d00837bSTrond Myklebust } else 10995d00837bSTrond Myklebust task->tk_status = 0; 11001da177e4SLinus Torvalds } 11011da177e4SLinus Torvalds 11029903cd1cSChuck Lever /** 11037f3a1d1eSTrond Myklebust * xprt_request_wait_receive - wait for the reply to an RPC request 11047f3a1d1eSTrond Myklebust * @task: RPC task about to send a request 11057f3a1d1eSTrond Myklebust * 11067f3a1d1eSTrond Myklebust */ 11077f3a1d1eSTrond Myklebust void xprt_request_wait_receive(struct rpc_task *task) 11087f3a1d1eSTrond Myklebust { 11097f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 11107f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 11117f3a1d1eSTrond Myklebust 11127f3a1d1eSTrond Myklebust if (!test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 11137f3a1d1eSTrond Myklebust return; 11147f3a1d1eSTrond Myklebust /* 11157f3a1d1eSTrond Myklebust * Sleep on the pending queue if we're expecting a reply. 11167f3a1d1eSTrond Myklebust * The spinlock ensures atomicity between the test of 11177f3a1d1eSTrond Myklebust * req->rq_reply_bytes_recvd, and the call to rpc_sleep_on(). 11187f3a1d1eSTrond Myklebust */ 11197f3a1d1eSTrond Myklebust spin_lock(&xprt->queue_lock); 11207f3a1d1eSTrond Myklebust if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) { 11217f3a1d1eSTrond Myklebust xprt->ops->set_retrans_timeout(task); 11227f3a1d1eSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 11237f3a1d1eSTrond Myklebust /* 11247f3a1d1eSTrond Myklebust * Send an extra queue wakeup call if the 11257f3a1d1eSTrond Myklebust * connection was dropped in case the call to 11267f3a1d1eSTrond Myklebust * rpc_sleep_on() raced. 11277f3a1d1eSTrond Myklebust */ 11287f3a1d1eSTrond Myklebust if (xprt_request_retransmit_after_disconnect(task)) 11297f3a1d1eSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 11307f3a1d1eSTrond Myklebust task, -ENOTCONN); 11317f3a1d1eSTrond Myklebust } 11327f3a1d1eSTrond Myklebust spin_unlock(&xprt->queue_lock); 11337f3a1d1eSTrond Myklebust } 11347f3a1d1eSTrond Myklebust 1135944b0429STrond Myklebust static bool 1136944b0429STrond Myklebust xprt_request_need_enqueue_transmit(struct rpc_task *task, struct rpc_rqst *req) 1137944b0429STrond Myklebust { 1138762e4e67STrond Myklebust return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1139944b0429STrond Myklebust } 1140944b0429STrond Myklebust 1141944b0429STrond Myklebust /** 1142944b0429STrond Myklebust * xprt_request_enqueue_transmit - queue a task for transmission 1143944b0429STrond Myklebust * @task: pointer to rpc_task 1144944b0429STrond Myklebust * 1145944b0429STrond Myklebust * Add a task to the transmission queue. 1146944b0429STrond Myklebust */ 1147944b0429STrond Myklebust void 1148944b0429STrond Myklebust xprt_request_enqueue_transmit(struct rpc_task *task) 1149944b0429STrond Myklebust { 1150918f3c1fSTrond Myklebust struct rpc_rqst *pos, *req = task->tk_rqstp; 1151944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1152944b0429STrond Myklebust 1153944b0429STrond Myklebust if (xprt_request_need_enqueue_transmit(task, req)) { 1154e66721f0STrond Myklebust req->rq_bytes_sent = 0; 1155944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 115675891f50STrond Myklebust /* 115775891f50STrond Myklebust * Requests that carry congestion control credits are added 115875891f50STrond Myklebust * to the head of the list to avoid starvation issues. 115975891f50STrond Myklebust */ 116075891f50STrond Myklebust if (req->rq_cong) { 116175891f50STrond Myklebust xprt_clear_congestion_window_wait(xprt); 116275891f50STrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 116375891f50STrond Myklebust if (pos->rq_cong) 116475891f50STrond Myklebust continue; 116575891f50STrond Myklebust /* Note: req is added _before_ pos */ 116675891f50STrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 116775891f50STrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 116875891f50STrond Myklebust goto out; 116975891f50STrond Myklebust } 117086aeee0eSTrond Myklebust } else if (RPC_IS_SWAPPER(task)) { 117186aeee0eSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 117286aeee0eSTrond Myklebust if (pos->rq_cong || pos->rq_bytes_sent) 117386aeee0eSTrond Myklebust continue; 117486aeee0eSTrond Myklebust if (RPC_IS_SWAPPER(pos->rq_task)) 117586aeee0eSTrond Myklebust continue; 117686aeee0eSTrond Myklebust /* Note: req is added _before_ pos */ 117786aeee0eSTrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 117886aeee0eSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 117986aeee0eSTrond Myklebust goto out; 118086aeee0eSTrond Myklebust } 1181deaa5c96SChuck Lever } else if (!req->rq_seqno) { 1182918f3c1fSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 1183918f3c1fSTrond Myklebust if (pos->rq_task->tk_owner != task->tk_owner) 1184918f3c1fSTrond Myklebust continue; 1185918f3c1fSTrond Myklebust list_add_tail(&req->rq_xmit2, &pos->rq_xmit2); 1186918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit); 1187918f3c1fSTrond Myklebust goto out; 1188918f3c1fSTrond Myklebust } 118975891f50STrond Myklebust } 1190944b0429STrond Myklebust list_add_tail(&req->rq_xmit, &xprt->xmit_queue); 1191918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 1192918f3c1fSTrond Myklebust out: 1193944b0429STrond Myklebust set_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1194944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1195944b0429STrond Myklebust } 1196944b0429STrond Myklebust } 1197944b0429STrond Myklebust 1198944b0429STrond Myklebust /** 1199944b0429STrond Myklebust * xprt_request_dequeue_transmit_locked - remove a task from the transmission queue 1200944b0429STrond Myklebust * @task: pointer to rpc_task 1201944b0429STrond Myklebust * 1202944b0429STrond Myklebust * Remove a task from the transmission queue 1203944b0429STrond Myklebust * Caller must hold xprt->queue_lock 1204944b0429STrond Myklebust */ 1205944b0429STrond Myklebust static void 1206944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(struct rpc_task *task) 1207944b0429STrond Myklebust { 1208918f3c1fSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1209918f3c1fSTrond Myklebust 1210918f3c1fSTrond Myklebust if (!test_and_clear_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 1211918f3c1fSTrond Myklebust return; 1212918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit)) { 1213918f3c1fSTrond Myklebust list_del(&req->rq_xmit); 1214918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit2)) { 1215918f3c1fSTrond Myklebust struct rpc_rqst *next = list_first_entry(&req->rq_xmit2, 1216918f3c1fSTrond Myklebust struct rpc_rqst, rq_xmit2); 1217918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1218918f3c1fSTrond Myklebust list_add_tail(&next->rq_xmit, &next->rq_xprt->xmit_queue); 1219918f3c1fSTrond Myklebust } 1220918f3c1fSTrond Myklebust } else 1221918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1222944b0429STrond Myklebust } 1223944b0429STrond Myklebust 1224944b0429STrond Myklebust /** 1225944b0429STrond Myklebust * xprt_request_dequeue_transmit - remove a task from the transmission queue 1226944b0429STrond Myklebust * @task: pointer to rpc_task 1227944b0429STrond Myklebust * 1228944b0429STrond Myklebust * Remove a task from the transmission queue 1229944b0429STrond Myklebust */ 1230944b0429STrond Myklebust static void 1231944b0429STrond Myklebust xprt_request_dequeue_transmit(struct rpc_task *task) 1232944b0429STrond Myklebust { 1233944b0429STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1234944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1235944b0429STrond Myklebust 1236944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 1237944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1238944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1239944b0429STrond Myklebust } 1240944b0429STrond Myklebust 12417f3a1d1eSTrond Myklebust /** 12429d96acbcSTrond Myklebust * xprt_request_prepare - prepare an encoded request for transport 12439d96acbcSTrond Myklebust * @req: pointer to rpc_rqst 12449d96acbcSTrond Myklebust * 12459d96acbcSTrond Myklebust * Calls into the transport layer to do whatever is needed to prepare 12469d96acbcSTrond Myklebust * the request for transmission or receive. 12479d96acbcSTrond Myklebust */ 12489d96acbcSTrond Myklebust void 12499d96acbcSTrond Myklebust xprt_request_prepare(struct rpc_rqst *req) 12509d96acbcSTrond Myklebust { 12519d96acbcSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12529d96acbcSTrond Myklebust 12539d96acbcSTrond Myklebust if (xprt->ops->prepare_request) 12549d96acbcSTrond Myklebust xprt->ops->prepare_request(req); 12559d96acbcSTrond Myklebust } 12569d96acbcSTrond Myklebust 12579d96acbcSTrond Myklebust /** 1258762e4e67STrond Myklebust * xprt_request_need_retransmit - Test if a task needs retransmission 1259762e4e67STrond Myklebust * @task: pointer to rpc_task 1260762e4e67STrond Myklebust * 1261762e4e67STrond Myklebust * Test for whether a connection breakage requires the task to retransmit 1262762e4e67STrond Myklebust */ 1263762e4e67STrond Myklebust bool 1264762e4e67STrond Myklebust xprt_request_need_retransmit(struct rpc_task *task) 1265762e4e67STrond Myklebust { 1266762e4e67STrond Myklebust return xprt_request_retransmit_after_disconnect(task); 1267762e4e67STrond Myklebust } 1268762e4e67STrond Myklebust 1269762e4e67STrond Myklebust /** 12709903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 12719903cd1cSChuck Lever * @task: RPC task about to send a request 12729903cd1cSChuck Lever * 12731da177e4SLinus Torvalds */ 127490051ea7STrond Myklebust bool xprt_prepare_transmit(struct rpc_task *task) 12751da177e4SLinus Torvalds { 12761da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 12771da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 12781da177e4SLinus Torvalds 127946121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 12801da177e4SLinus Torvalds 12815f2f6bd9STrond Myklebust if (!xprt_lock_write(xprt, task)) { 12825f2f6bd9STrond Myklebust /* Race breaker: someone may have transmitted us */ 1283944b0429STrond Myklebust if (!test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 12845f2f6bd9STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, 12855f2f6bd9STrond Myklebust task, 0); 12865f2f6bd9STrond Myklebust return false; 12875f2f6bd9STrond Myklebust 12888a19a0b6STrond Myklebust } 12895f2f6bd9STrond Myklebust return true; 12901da177e4SLinus Torvalds } 12911da177e4SLinus Torvalds 1292e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 12935e5ce5beSTrond Myklebust { 1294343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 12955e5ce5beSTrond Myklebust } 12965e5ce5beSTrond Myklebust 12979903cd1cSChuck Lever /** 129889f90fe1STrond Myklebust * xprt_request_transmit - send an RPC request on a transport 129989f90fe1STrond Myklebust * @req: pointer to request to transmit 130089f90fe1STrond Myklebust * @snd_task: RPC task that owns the transport lock 13019903cd1cSChuck Lever * 130289f90fe1STrond Myklebust * This performs the transmission of a single request. 130389f90fe1STrond Myklebust * Note that if the request is not the same as snd_task, then it 130489f90fe1STrond Myklebust * does need to be pinned. 130589f90fe1STrond Myklebust * Returns '0' on success. 13069903cd1cSChuck Lever */ 130789f90fe1STrond Myklebust static int 130889f90fe1STrond Myklebust xprt_request_transmit(struct rpc_rqst *req, struct rpc_task *snd_task) 13091da177e4SLinus Torvalds { 13101da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 131189f90fe1STrond Myklebust struct rpc_task *task = req->rq_task; 131290d91b0cSTrond Myklebust unsigned int connect_cookie; 1313dcbbeda8STrond Myklebust int is_retrans = RPC_WAS_SENT(task); 1314ff699ea8SChuck Lever int status; 13151da177e4SLinus Torvalds 131646121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 13171da177e4SLinus Torvalds 1318edc81dcdSTrond Myklebust if (!req->rq_bytes_sent) { 131989f90fe1STrond Myklebust if (xprt_request_data_received(task)) { 132089f90fe1STrond Myklebust status = 0; 1321944b0429STrond Myklebust goto out_dequeue; 132289f90fe1STrond Myklebust } 13233021a5bbSTrond Myklebust /* Verify that our message lies in the RPCSEC_GSS window */ 1324edc81dcdSTrond Myklebust if (rpcauth_xmit_need_reencode(task)) { 132589f90fe1STrond Myklebust status = -EBADMSG; 1326944b0429STrond Myklebust goto out_dequeue; 13273021a5bbSTrond Myklebust } 13281da177e4SLinus Torvalds } 13291da177e4SLinus Torvalds 1330dcbbeda8STrond Myklebust /* 1331dcbbeda8STrond Myklebust * Update req->rq_ntrans before transmitting to avoid races with 1332dcbbeda8STrond Myklebust * xprt_update_rtt(), which needs to know that it is recording a 1333dcbbeda8STrond Myklebust * reply to the first transmission. 1334dcbbeda8STrond Myklebust */ 1335dcbbeda8STrond Myklebust req->rq_ntrans++; 1336dcbbeda8STrond Myklebust 133790d91b0cSTrond Myklebust connect_cookie = xprt->connect_cookie; 1338adfa7144STrond Myklebust status = xprt->ops->send_request(req); 13393705ad64SJeff Layton trace_xprt_transmit(xprt, req->rq_xid, status); 1340c8485e4dSTrond Myklebust if (status != 0) { 1341dcbbeda8STrond Myklebust req->rq_ntrans--; 134289f90fe1STrond Myklebust return status; 1343c8485e4dSTrond Myklebust } 13447ebbbc6eSTrond Myklebust 1345dcbbeda8STrond Myklebust if (is_retrans) 1346dcbbeda8STrond Myklebust task->tk_client->cl_stats->rpcretrans++; 1347dcbbeda8STrond Myklebust 13484a068258SChuck Lever xprt_inject_disconnect(xprt); 1349c8485e4dSTrond Myklebust 135046121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 1351468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 1352fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 1353262ca07dSChuck Lever 1354262ca07dSChuck Lever xprt->stat.sends++; 1355262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 1356262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 135715a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 135815a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 1359fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 136090d91b0cSTrond Myklebust 136190d91b0cSTrond Myklebust req->rq_connect_cookie = connect_cookie; 1362944b0429STrond Myklebust out_dequeue: 1363944b0429STrond Myklebust xprt_request_dequeue_transmit(task); 136489f90fe1STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, task, status); 136589f90fe1STrond Myklebust return status; 136689f90fe1STrond Myklebust } 136789f90fe1STrond Myklebust 136889f90fe1STrond Myklebust /** 136989f90fe1STrond Myklebust * xprt_transmit - send an RPC request on a transport 137089f90fe1STrond Myklebust * @task: controlling RPC task 137189f90fe1STrond Myklebust * 137289f90fe1STrond Myklebust * Attempts to drain the transmit queue. On exit, either the transport 137389f90fe1STrond Myklebust * signalled an error that needs to be handled before transmission can 137489f90fe1STrond Myklebust * resume, or @task finished transmitting, and detected that it already 137589f90fe1STrond Myklebust * received a reply. 137689f90fe1STrond Myklebust */ 137789f90fe1STrond Myklebust void 137889f90fe1STrond Myklebust xprt_transmit(struct rpc_task *task) 137989f90fe1STrond Myklebust { 138089f90fe1STrond Myklebust struct rpc_rqst *next, *req = task->tk_rqstp; 138189f90fe1STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 138289f90fe1STrond Myklebust int status; 138389f90fe1STrond Myklebust 138489f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 138589f90fe1STrond Myklebust while (!list_empty(&xprt->xmit_queue)) { 138689f90fe1STrond Myklebust next = list_first_entry(&xprt->xmit_queue, 138789f90fe1STrond Myklebust struct rpc_rqst, rq_xmit); 138889f90fe1STrond Myklebust xprt_pin_rqst(next); 138989f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 139089f90fe1STrond Myklebust status = xprt_request_transmit(next, task); 139189f90fe1STrond Myklebust if (status == -EBADMSG && next != req) 139289f90fe1STrond Myklebust status = 0; 139389f90fe1STrond Myklebust cond_resched(); 139489f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 139589f90fe1STrond Myklebust xprt_unpin_rqst(next); 139689f90fe1STrond Myklebust if (status == 0) { 139789f90fe1STrond Myklebust if (!xprt_request_data_received(task) || 139889f90fe1STrond Myklebust test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 139989f90fe1STrond Myklebust continue; 1400c544577dSTrond Myklebust } else if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 140189f90fe1STrond Myklebust task->tk_status = status; 140289f90fe1STrond Myklebust break; 140389f90fe1STrond Myklebust } 140489f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 14051da177e4SLinus Torvalds } 14061da177e4SLinus Torvalds 1407ba60eb25STrond Myklebust static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) 1408ba60eb25STrond Myklebust { 1409ba60eb25STrond Myklebust set_bit(XPRT_CONGESTED, &xprt->state); 1410ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1411ba60eb25STrond Myklebust } 1412ba60eb25STrond Myklebust 1413ba60eb25STrond Myklebust static void xprt_wake_up_backlog(struct rpc_xprt *xprt) 1414ba60eb25STrond Myklebust { 1415ba60eb25STrond Myklebust if (rpc_wake_up_next(&xprt->backlog) == NULL) 1416ba60eb25STrond Myklebust clear_bit(XPRT_CONGESTED, &xprt->state); 1417ba60eb25STrond Myklebust } 1418ba60eb25STrond Myklebust 1419ba60eb25STrond Myklebust static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) 1420ba60eb25STrond Myklebust { 1421ba60eb25STrond Myklebust bool ret = false; 1422ba60eb25STrond Myklebust 1423ba60eb25STrond Myklebust if (!test_bit(XPRT_CONGESTED, &xprt->state)) 1424ba60eb25STrond Myklebust goto out; 1425ba60eb25STrond Myklebust spin_lock(&xprt->reserve_lock); 1426ba60eb25STrond Myklebust if (test_bit(XPRT_CONGESTED, &xprt->state)) { 1427ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1428ba60eb25STrond Myklebust ret = true; 1429ba60eb25STrond Myklebust } 1430ba60eb25STrond Myklebust spin_unlock(&xprt->reserve_lock); 1431ba60eb25STrond Myklebust out: 1432ba60eb25STrond Myklebust return ret; 1433ba60eb25STrond Myklebust } 1434ba60eb25STrond Myklebust 143592ea011fSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt) 1436d9ba131dSTrond Myklebust { 1437d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 1438d9ba131dSTrond Myklebust 1439ff699ea8SChuck Lever if (xprt->num_reqs >= xprt->max_reqs) 1440d9ba131dSTrond Myklebust goto out; 1441ff699ea8SChuck Lever ++xprt->num_reqs; 144292ea011fSTrond Myklebust spin_unlock(&xprt->reserve_lock); 144392ea011fSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_NOFS); 144492ea011fSTrond Myklebust spin_lock(&xprt->reserve_lock); 1445d9ba131dSTrond Myklebust if (req != NULL) 1446d9ba131dSTrond Myklebust goto out; 1447ff699ea8SChuck Lever --xprt->num_reqs; 1448d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 1449d9ba131dSTrond Myklebust out: 1450d9ba131dSTrond Myklebust return req; 1451d9ba131dSTrond Myklebust } 1452d9ba131dSTrond Myklebust 1453d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1454d9ba131dSTrond Myklebust { 1455ff699ea8SChuck Lever if (xprt->num_reqs > xprt->min_reqs) { 1456ff699ea8SChuck Lever --xprt->num_reqs; 1457d9ba131dSTrond Myklebust kfree(req); 1458d9ba131dSTrond Myklebust return true; 1459d9ba131dSTrond Myklebust } 1460d9ba131dSTrond Myklebust return false; 1461d9ba131dSTrond Myklebust } 1462d9ba131dSTrond Myklebust 1463f39c1bfbSTrond Myklebust void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 14641da177e4SLinus Torvalds { 1465d9ba131dSTrond Myklebust struct rpc_rqst *req; 14661da177e4SLinus Torvalds 1467f39c1bfbSTrond Myklebust spin_lock(&xprt->reserve_lock); 14681da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 1469d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 1470d9ba131dSTrond Myklebust list_del(&req->rq_list); 1471d9ba131dSTrond Myklebust goto out_init_req; 1472d9ba131dSTrond Myklebust } 147392ea011fSTrond Myklebust req = xprt_dynamic_alloc_slot(xprt); 1474d9ba131dSTrond Myklebust if (!IS_ERR(req)) 1475d9ba131dSTrond Myklebust goto out_init_req; 1476d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 1477d9ba131dSTrond Myklebust case -ENOMEM: 1478d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 1479d9ba131dSTrond Myklebust "failed! Retrying\n"); 14801afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 1481d9ba131dSTrond Myklebust break; 1482d9ba131dSTrond Myklebust case -EAGAIN: 1483ba60eb25STrond Myklebust xprt_add_backlog(xprt, task); 1484d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 1485e9d47639SGustavo A. R. Silva /* fall through */ 14861afeaf5cSTrond Myklebust default: 1487d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 14881afeaf5cSTrond Myklebust } 1489f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 1490d9ba131dSTrond Myklebust return; 1491d9ba131dSTrond Myklebust out_init_req: 1492ff699ea8SChuck Lever xprt->stat.max_slots = max_t(unsigned int, xprt->stat.max_slots, 1493ff699ea8SChuck Lever xprt->num_reqs); 149437ac86c3SChuck Lever spin_unlock(&xprt->reserve_lock); 149537ac86c3SChuck Lever 1496d9ba131dSTrond Myklebust task->tk_status = 0; 14971da177e4SLinus Torvalds task->tk_rqstp = req; 14981da177e4SLinus Torvalds } 1499f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_alloc_slot); 1500f39c1bfbSTrond Myklebust 1501a9cde23aSChuck Lever void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1502ee5ebe85STrond Myklebust { 1503ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1504c25573b5STrond Myklebust if (!xprt_dynamic_free_slot(xprt, req)) { 1505c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1506ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1507c25573b5STrond Myklebust } 1508ba60eb25STrond Myklebust xprt_wake_up_backlog(xprt); 1509ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1510ee5ebe85STrond Myklebust } 1511a9cde23aSChuck Lever EXPORT_SYMBOL_GPL(xprt_free_slot); 1512ee5ebe85STrond Myklebust 151321de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 151421de0a95STrond Myklebust { 151521de0a95STrond Myklebust struct rpc_rqst *req; 151621de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 151721de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 151821de0a95STrond Myklebust list_del(&req->rq_list); 151921de0a95STrond Myklebust kfree(req); 152021de0a95STrond Myklebust } 152121de0a95STrond Myklebust } 152221de0a95STrond Myklebust 1523d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1524d9ba131dSTrond Myklebust unsigned int num_prealloc, 1525d9ba131dSTrond Myklebust unsigned int max_alloc) 1526bd1722d4SPavel Emelyanov { 1527bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 152821de0a95STrond Myklebust struct rpc_rqst *req; 152921de0a95STrond Myklebust int i; 1530bd1722d4SPavel Emelyanov 1531bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1532bd1722d4SPavel Emelyanov if (xprt == NULL) 1533bd1722d4SPavel Emelyanov goto out; 1534bd1722d4SPavel Emelyanov 153521de0a95STrond Myklebust xprt_init(xprt, net); 153621de0a95STrond Myklebust 153721de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 153821de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 153921de0a95STrond Myklebust if (!req) 15408313164cSwangweidong goto out_free; 154121de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 154221de0a95STrond Myklebust } 1543d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1544d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1545d9ba131dSTrond Myklebust else 154621de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1547d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1548ff699ea8SChuck Lever xprt->num_reqs = num_prealloc; 1549bd1722d4SPavel Emelyanov 1550bd1722d4SPavel Emelyanov return xprt; 1551bd1722d4SPavel Emelyanov 1552bd1722d4SPavel Emelyanov out_free: 155321de0a95STrond Myklebust xprt_free(xprt); 1554bd1722d4SPavel Emelyanov out: 1555bd1722d4SPavel Emelyanov return NULL; 1556bd1722d4SPavel Emelyanov } 1557bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1558bd1722d4SPavel Emelyanov 1559e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1560e204e621SPavel Emelyanov { 156137aa2133SPavel Emelyanov put_net(xprt->xprt_net); 156221de0a95STrond Myklebust xprt_free_all_slots(xprt); 1563fda1bfefSTrond Myklebust kfree_rcu(xprt, rcu); 1564e204e621SPavel Emelyanov } 1565e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1566e204e621SPavel Emelyanov 1567902c5887STrond Myklebust static void 1568902c5887STrond Myklebust xprt_init_connect_cookie(struct rpc_rqst *req, struct rpc_xprt *xprt) 1569902c5887STrond Myklebust { 1570902c5887STrond Myklebust req->rq_connect_cookie = xprt_connect_cookie(xprt) - 1; 1571902c5887STrond Myklebust } 1572902c5887STrond Myklebust 15739dc6edcfSTrond Myklebust static __be32 15749dc6edcfSTrond Myklebust xprt_alloc_xid(struct rpc_xprt *xprt) 15759dc6edcfSTrond Myklebust { 15769dc6edcfSTrond Myklebust __be32 xid; 15779dc6edcfSTrond Myklebust 15789dc6edcfSTrond Myklebust spin_lock(&xprt->reserve_lock); 15799dc6edcfSTrond Myklebust xid = (__force __be32)xprt->xid++; 15809dc6edcfSTrond Myklebust spin_unlock(&xprt->reserve_lock); 15819dc6edcfSTrond Myklebust return xid; 15829dc6edcfSTrond Myklebust } 15839dc6edcfSTrond Myklebust 15849dc6edcfSTrond Myklebust static void 15859dc6edcfSTrond Myklebust xprt_init_xid(struct rpc_xprt *xprt) 15869dc6edcfSTrond Myklebust { 15879dc6edcfSTrond Myklebust xprt->xid = prandom_u32(); 15889dc6edcfSTrond Myklebust } 15899dc6edcfSTrond Myklebust 15909dc6edcfSTrond Myklebust static void 15919dc6edcfSTrond Myklebust xprt_request_init(struct rpc_task *task) 15929dc6edcfSTrond Myklebust { 15939dc6edcfSTrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 15949dc6edcfSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 15959dc6edcfSTrond Myklebust 15969dc6edcfSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 15979dc6edcfSTrond Myklebust req->rq_task = task; 15989dc6edcfSTrond Myklebust req->rq_xprt = xprt; 15999dc6edcfSTrond Myklebust req->rq_buffer = NULL; 16009dc6edcfSTrond Myklebust req->rq_xid = xprt_alloc_xid(xprt); 1601902c5887STrond Myklebust xprt_init_connect_cookie(req, xprt); 16029dc6edcfSTrond Myklebust req->rq_bytes_sent = 0; 16039dc6edcfSTrond Myklebust req->rq_snd_buf.len = 0; 16049dc6edcfSTrond Myklebust req->rq_snd_buf.buflen = 0; 16059dc6edcfSTrond Myklebust req->rq_rcv_buf.len = 0; 16069dc6edcfSTrond Myklebust req->rq_rcv_buf.buflen = 0; 160771700bb9STrond Myklebust req->rq_snd_buf.bvec = NULL; 160871700bb9STrond Myklebust req->rq_rcv_buf.bvec = NULL; 16099dc6edcfSTrond Myklebust req->rq_release_snd_buf = NULL; 16109dc6edcfSTrond Myklebust xprt_reset_majortimeo(req); 16119dc6edcfSTrond Myklebust dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 16129dc6edcfSTrond Myklebust req, ntohl(req->rq_xid)); 16139dc6edcfSTrond Myklebust } 16149dc6edcfSTrond Myklebust 16159dc6edcfSTrond Myklebust static void 16169dc6edcfSTrond Myklebust xprt_do_reserve(struct rpc_xprt *xprt, struct rpc_task *task) 16179dc6edcfSTrond Myklebust { 16189dc6edcfSTrond Myklebust xprt->ops->alloc_slot(xprt, task); 16199dc6edcfSTrond Myklebust if (task->tk_rqstp != NULL) 16209dc6edcfSTrond Myklebust xprt_request_init(task); 16219dc6edcfSTrond Myklebust } 16229dc6edcfSTrond Myklebust 16239903cd1cSChuck Lever /** 16249903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 16259903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 16269903cd1cSChuck Lever * 1627ba60eb25STrond Myklebust * If the transport is marked as being congested, or if no more 1628ba60eb25STrond Myklebust * slots are available, place the task on the transport's 16299903cd1cSChuck Lever * backlog queue. 16309903cd1cSChuck Lever */ 16319903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 16321da177e4SLinus Torvalds { 1633fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 16341da177e4SLinus Torvalds 163543cedbf0STrond Myklebust task->tk_status = 0; 163643cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 163743cedbf0STrond Myklebust return; 163843cedbf0STrond Myklebust 163943cedbf0STrond Myklebust task->tk_timeout = 0; 164043cedbf0STrond Myklebust task->tk_status = -EAGAIN; 1641ba60eb25STrond Myklebust if (!xprt_throttle_congested(xprt, task)) 16429dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 1643ba60eb25STrond Myklebust } 1644ba60eb25STrond Myklebust 1645ba60eb25STrond Myklebust /** 1646ba60eb25STrond Myklebust * xprt_retry_reserve - allocate an RPC request slot 1647ba60eb25STrond Myklebust * @task: RPC task requesting a slot allocation 1648ba60eb25STrond Myklebust * 1649ba60eb25STrond Myklebust * If no more slots are available, place the task on the transport's 1650ba60eb25STrond Myklebust * backlog queue. 1651ba60eb25STrond Myklebust * Note that the only difference with xprt_reserve is that we now 1652ba60eb25STrond Myklebust * ignore the value of the XPRT_CONGESTED flag. 1653ba60eb25STrond Myklebust */ 1654ba60eb25STrond Myklebust void xprt_retry_reserve(struct rpc_task *task) 1655ba60eb25STrond Myklebust { 1656fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 1657ba60eb25STrond Myklebust 1658ba60eb25STrond Myklebust task->tk_status = 0; 1659ba60eb25STrond Myklebust if (task->tk_rqstp != NULL) 1660ba60eb25STrond Myklebust return; 1661ba60eb25STrond Myklebust 1662ba60eb25STrond Myklebust task->tk_timeout = 0; 1663ba60eb25STrond Myklebust task->tk_status = -EAGAIN; 16649dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 16651da177e4SLinus Torvalds } 16661da177e4SLinus Torvalds 1667edc81dcdSTrond Myklebust static void 1668edc81dcdSTrond Myklebust xprt_request_dequeue_all(struct rpc_task *task, struct rpc_rqst *req) 1669edc81dcdSTrond Myklebust { 1670edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1671edc81dcdSTrond Myklebust 1672944b0429STrond Myklebust if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) || 1673944b0429STrond Myklebust test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || 1674edc81dcdSTrond Myklebust xprt_is_pinned_rqst(req)) { 1675edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1676944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1677edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 1678edc81dcdSTrond Myklebust while (xprt_is_pinned_rqst(req)) { 1679edc81dcdSTrond Myklebust set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1680edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1681edc81dcdSTrond Myklebust xprt_wait_on_pinned_rqst(req); 1682edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1683edc81dcdSTrond Myklebust clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1684edc81dcdSTrond Myklebust } 1685edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1686edc81dcdSTrond Myklebust } 1687edc81dcdSTrond Myklebust } 1688edc81dcdSTrond Myklebust 16899903cd1cSChuck Lever /** 16909903cd1cSChuck Lever * xprt_release - release an RPC request slot 16919903cd1cSChuck Lever * @task: task which is finished with the slot 16929903cd1cSChuck Lever * 16931da177e4SLinus Torvalds */ 16949903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 16951da177e4SLinus Torvalds { 169655ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 169787ed5003STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 16981da177e4SLinus Torvalds 169987ed5003STrond Myklebust if (req == NULL) { 170087ed5003STrond Myklebust if (task->tk_client) { 1701fb43d172STrond Myklebust xprt = task->tk_xprt; 170287ed5003STrond Myklebust xprt_release_write(xprt, task); 170387ed5003STrond Myklebust } 17041da177e4SLinus Torvalds return; 170587ed5003STrond Myklebust } 170655ae1aabSRicardo Labiaga 170755ae1aabSRicardo Labiaga xprt = req->rq_xprt; 17080a702195SWeston Andros Adamson if (task->tk_ops->rpc_count_stats != NULL) 17090a702195SWeston Andros Adamson task->tk_ops->rpc_count_stats(task, task->tk_calldata); 17100a702195SWeston Andros Adamson else if (task->tk_client) 17110a702195SWeston Andros Adamson rpc_count_iostats(task, task->tk_client->cl_metrics); 1712edc81dcdSTrond Myklebust xprt_request_dequeue_all(task, req); 17134a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 171449e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1715a58dd398SChuck Lever if (xprt->ops->release_request) 1716a58dd398SChuck Lever xprt->ops->release_request(task); 17171da177e4SLinus Torvalds xprt->last_used = jiffies; 1718ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 17194a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1720ee5ebe85STrond Myklebust if (req->rq_buffer) 17213435c74aSChuck Lever xprt->ops->buf_free(task); 17224a068258SChuck Lever xprt_inject_disconnect(xprt); 17239d96acbcSTrond Myklebust xdr_free_bvec(&req->rq_rcv_buf); 1724a17c2153STrond Myklebust if (req->rq_cred != NULL) 1725a17c2153STrond Myklebust put_rpccred(req->rq_cred); 17261da177e4SLinus Torvalds task->tk_rqstp = NULL; 1727ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1728ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 172955ae1aabSRicardo Labiaga 173046121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 1731ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1732a9cde23aSChuck Lever xprt->ops->free_slot(xprt, req); 1733ee5ebe85STrond Myklebust else 1734c9acb42eSTrond Myklebust xprt_free_bc_request(req); 17351da177e4SLinus Torvalds } 17361da177e4SLinus Torvalds 1737902c5887STrond Myklebust #ifdef CONFIG_SUNRPC_BACKCHANNEL 1738902c5887STrond Myklebust void 1739902c5887STrond Myklebust xprt_init_bc_request(struct rpc_rqst *req, struct rpc_task *task) 1740902c5887STrond Myklebust { 1741902c5887STrond Myklebust struct xdr_buf *xbufp = &req->rq_snd_buf; 1742902c5887STrond Myklebust 1743902c5887STrond Myklebust task->tk_rqstp = req; 1744902c5887STrond Myklebust req->rq_task = task; 1745902c5887STrond Myklebust xprt_init_connect_cookie(req, req->rq_xprt); 1746902c5887STrond Myklebust /* 1747902c5887STrond Myklebust * Set up the xdr_buf length. 1748902c5887STrond Myklebust * This also indicates that the buffer is XDR encoded already. 1749902c5887STrond Myklebust */ 1750902c5887STrond Myklebust xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1751902c5887STrond Myklebust xbufp->tail[0].iov_len; 1752902c5887STrond Myklebust req->rq_bytes_sent = 0; 1753902c5887STrond Myklebust } 1754902c5887STrond Myklebust #endif 1755902c5887STrond Myklebust 175621de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1757c2866763SChuck Lever { 175830c5116bSTrond Myklebust kref_init(&xprt->kref); 1759c2866763SChuck Lever 1760c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1761c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 176275c84151STrond Myklebust spin_lock_init(&xprt->queue_lock); 1763c2866763SChuck Lever 1764c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 176595f7691dSTrond Myklebust xprt->recv_queue = RB_ROOT; 1766944b0429STrond Myklebust INIT_LIST_HEAD(&xprt->xmit_queue); 17679e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1768f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1769f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 17709e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 177180b14d5eSTrond Myklebust INIT_LIST_HEAD(&xprt->xprt_switch); 1772f9acac1aSRicardo Labiaga 1773c2866763SChuck Lever xprt->last_used = jiffies; 1774c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1775a509050bSChuck Lever xprt->bind_index = 0; 1776c2866763SChuck Lever 1777c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1778c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 177979c99152STrond Myklebust rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 1780c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1781c2866763SChuck Lever 1782c2866763SChuck Lever xprt_init_xid(xprt); 1783c2866763SChuck Lever 178421de0a95STrond Myklebust xprt->xprt_net = get_net(net); 17858d9266ffSTrond Myklebust } 17868d9266ffSTrond Myklebust 17878d9266ffSTrond Myklebust /** 17888d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 17898d9266ffSTrond Myklebust * @args: rpc transport creation arguments 17908d9266ffSTrond Myklebust * 17918d9266ffSTrond Myklebust */ 17928d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 17938d9266ffSTrond Myklebust { 17948d9266ffSTrond Myklebust struct rpc_xprt *xprt; 17958d9266ffSTrond Myklebust struct xprt_class *t; 17968d9266ffSTrond Myklebust 17978d9266ffSTrond Myklebust spin_lock(&xprt_list_lock); 17988d9266ffSTrond Myklebust list_for_each_entry(t, &xprt_list, list) { 17998d9266ffSTrond Myklebust if (t->ident == args->ident) { 18008d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 18018d9266ffSTrond Myklebust goto found; 18028d9266ffSTrond Myklebust } 18038d9266ffSTrond Myklebust } 18048d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 18053c45ddf8SChuck Lever dprintk("RPC: transport (%d) not supported\n", args->ident); 18068d9266ffSTrond Myklebust return ERR_PTR(-EIO); 18078d9266ffSTrond Myklebust 18088d9266ffSTrond Myklebust found: 18098d9266ffSTrond Myklebust xprt = t->setup(args); 18108d9266ffSTrond Myklebust if (IS_ERR(xprt)) { 18118d9266ffSTrond Myklebust dprintk("RPC: xprt_create_transport: failed, %ld\n", 18128d9266ffSTrond Myklebust -PTR_ERR(xprt)); 181321de0a95STrond Myklebust goto out; 18148d9266ffSTrond Myklebust } 181533d90ac0SJ. Bruce Fields if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) 181633d90ac0SJ. Bruce Fields xprt->idle_timeout = 0; 181721de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 181821de0a95STrond Myklebust if (xprt_has_timer(xprt)) 1819ff861c4dSKees Cook timer_setup(&xprt->timer, xprt_init_autodisconnect, 0); 182021de0a95STrond Myklebust else 1821ff861c4dSKees Cook timer_setup(&xprt->timer, NULL, 0); 18224e0038b6STrond Myklebust 18234e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 18244e0038b6STrond Myklebust xprt_destroy(xprt); 18254e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 18264e0038b6STrond Myklebust } 18274e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 18284e0038b6STrond Myklebust if (xprt->servername == NULL) { 18294e0038b6STrond Myklebust xprt_destroy(xprt); 18304e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 18314e0038b6STrond Myklebust } 18324e0038b6STrond Myklebust 18333f940098SJeff Layton rpc_xprt_debugfs_register(xprt); 1834388f0c77SJeff Layton 1835c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1836c2866763SChuck Lever xprt->max_reqs); 183721de0a95STrond Myklebust out: 1838c2866763SChuck Lever return xprt; 1839c2866763SChuck Lever } 1840c2866763SChuck Lever 1841528fd354STrond Myklebust static void xprt_destroy_cb(struct work_struct *work) 1842528fd354STrond Myklebust { 1843528fd354STrond Myklebust struct rpc_xprt *xprt = 1844528fd354STrond Myklebust container_of(work, struct rpc_xprt, task_cleanup); 1845528fd354STrond Myklebust 1846528fd354STrond Myklebust rpc_xprt_debugfs_unregister(xprt); 1847528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1848528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1849528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1850528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1851528fd354STrond Myklebust kfree(xprt->servername); 1852528fd354STrond Myklebust /* 1853528fd354STrond Myklebust * Tear down transport state and free the rpc_xprt 1854528fd354STrond Myklebust */ 1855528fd354STrond Myklebust xprt->ops->destroy(xprt); 1856528fd354STrond Myklebust } 1857528fd354STrond Myklebust 18589903cd1cSChuck Lever /** 18599903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 1860a8de240aSTrond Myklebust * @xprt: transport to destroy 18619903cd1cSChuck Lever * 18621da177e4SLinus Torvalds */ 1863a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 18641da177e4SLinus Torvalds { 18651da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 186679234c3dSTrond Myklebust 1867528fd354STrond Myklebust /* 1868528fd354STrond Myklebust * Exclude transport connect/disconnect handlers and autoclose 1869528fd354STrond Myklebust */ 187079234c3dSTrond Myklebust wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); 187179234c3dSTrond Myklebust 18720065db32STrond Myklebust del_timer_sync(&xprt->timer); 1873c8541ecdSChuck Lever 1874c8541ecdSChuck Lever /* 1875528fd354STrond Myklebust * Destroy sockets etc from the system workqueue so they can 1876528fd354STrond Myklebust * safely flush receive work running on rpciod. 1877c8541ecdSChuck Lever */ 1878528fd354STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_destroy_cb); 1879528fd354STrond Myklebust schedule_work(&xprt->task_cleanup); 18806b6ca86bSTrond Myklebust } 18811da177e4SLinus Torvalds 188230c5116bSTrond Myklebust static void xprt_destroy_kref(struct kref *kref) 188330c5116bSTrond Myklebust { 188430c5116bSTrond Myklebust xprt_destroy(container_of(kref, struct rpc_xprt, kref)); 188530c5116bSTrond Myklebust } 188630c5116bSTrond Myklebust 188730c5116bSTrond Myklebust /** 188830c5116bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 188930c5116bSTrond Myklebust * @xprt: pointer to the transport 189030c5116bSTrond Myklebust * 189130c5116bSTrond Myklebust */ 189230c5116bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 189330c5116bSTrond Myklebust { 189430c5116bSTrond Myklebust if (xprt != NULL && kref_get_unless_zero(&xprt->kref)) 189530c5116bSTrond Myklebust return xprt; 189630c5116bSTrond Myklebust return NULL; 189730c5116bSTrond Myklebust } 189830c5116bSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_get); 189930c5116bSTrond Myklebust 19006b6ca86bSTrond Myklebust /** 19016b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 19026b6ca86bSTrond Myklebust * @xprt: pointer to the transport 19036b6ca86bSTrond Myklebust * 19046b6ca86bSTrond Myklebust */ 19056b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 19066b6ca86bSTrond Myklebust { 190730c5116bSTrond Myklebust if (xprt != NULL) 190830c5116bSTrond Myklebust kref_put(&xprt->kref, xprt_destroy_kref); 19096b6ca86bSTrond Myklebust } 19105d252f90SChuck Lever EXPORT_SYMBOL_GPL(xprt_put); 1911