11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/net/sunrpc/xprt.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * This is a generic RPC call interface supporting congestion avoidance, 51da177e4SLinus Torvalds * and asynchronous calls. 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * The interface works like this: 81da177e4SLinus Torvalds * 91da177e4SLinus Torvalds * - When a process places a call, it allocates a request slot if 101da177e4SLinus Torvalds * one is available. Otherwise, it sleeps on the backlog queue 111da177e4SLinus Torvalds * (xprt_reserve). 121da177e4SLinus Torvalds * - Next, the caller puts together the RPC message, stuffs it into 1355aa4f58SChuck Lever * the request struct, and calls xprt_transmit(). 1455aa4f58SChuck Lever * - xprt_transmit sends the message and installs the caller on the 1555ae1aabSRicardo Labiaga * transport's wait list. At the same time, if a reply is expected, 1655ae1aabSRicardo Labiaga * it installs a timer that is run after the packet's timeout has 1755ae1aabSRicardo Labiaga * expired. 181da177e4SLinus Torvalds * - When a packet arrives, the data_ready handler walks the list of 1955aa4f58SChuck Lever * pending requests for that transport. If a matching XID is found, the 201da177e4SLinus Torvalds * caller is woken up, and the timer removed. 211da177e4SLinus Torvalds * - When no reply arrives within the timeout interval, the timer is 221da177e4SLinus Torvalds * fired by the kernel and runs xprt_timer(). It either adjusts the 231da177e4SLinus Torvalds * timeout values (minor timeout) or wakes up the caller with a status 241da177e4SLinus Torvalds * of -ETIMEDOUT. 251da177e4SLinus Torvalds * - When the caller receives a notification from RPC that a reply arrived, 261da177e4SLinus Torvalds * it should release the RPC slot, and process the reply. 271da177e4SLinus Torvalds * If the call timed out, it may choose to retry the operation by 281da177e4SLinus Torvalds * adjusting the initial timeout value, and simply calling rpc_call 291da177e4SLinus Torvalds * again. 301da177e4SLinus Torvalds * 311da177e4SLinus Torvalds * Support for async RPC is done through a set of RPC-specific scheduling 321da177e4SLinus Torvalds * primitives that `transparently' work for processes as well as async 331da177e4SLinus Torvalds * tasks that rely on callbacks. 341da177e4SLinus Torvalds * 351da177e4SLinus Torvalds * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> 3655aa4f58SChuck Lever * 3755aa4f58SChuck Lever * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> 381da177e4SLinus Torvalds */ 391da177e4SLinus Torvalds 40a246b010SChuck Lever #include <linux/module.h> 41a246b010SChuck Lever 421da177e4SLinus Torvalds #include <linux/types.h> 43a246b010SChuck Lever #include <linux/interrupt.h> 441da177e4SLinus Torvalds #include <linux/workqueue.h> 45bf3fcf89SChuck Lever #include <linux/net.h> 46ff839970SChuck Lever #include <linux/ktime.h> 471da177e4SLinus Torvalds 48a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 4911c556b3SChuck Lever #include <linux/sunrpc/metrics.h> 50c9acb42eSTrond Myklebust #include <linux/sunrpc/bc_xprt.h> 511da177e4SLinus Torvalds 5255ae1aabSRicardo Labiaga #include "sunrpc.h" 5355ae1aabSRicardo Labiaga 541da177e4SLinus Torvalds /* 551da177e4SLinus Torvalds * Local variables 561da177e4SLinus Torvalds */ 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds #ifdef RPC_DEBUG 591da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 601da177e4SLinus Torvalds #endif 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds /* 631da177e4SLinus Torvalds * Local functions 641da177e4SLinus Torvalds */ 6521de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 661da177e4SLinus Torvalds static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); 671da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 681da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 691da177e4SLinus Torvalds 705ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7181c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7281c098afS\"Talpey, Thomas\ 73555ee3afSChuck Lever /* 74555ee3afSChuck Lever * The transport code maintains an estimate on the maximum number of out- 75555ee3afSChuck Lever * standing RPC requests, using a smoothed version of the congestion 76555ee3afSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 77555ee3afSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 78555ee3afSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 79555ee3afSChuck Lever * 80555ee3afSChuck Lever * - a reply is received and 81555ee3afSChuck Lever * - a full number of requests are outstanding and 82555ee3afSChuck Lever * - the congestion window hasn't been updated recently. 83555ee3afSChuck Lever */ 84555ee3afSChuck Lever #define RPC_CWNDSHIFT (8U) 85555ee3afSChuck Lever #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 86555ee3afSChuck Lever #define RPC_INITCWND RPC_CWNDSCALE 87555ee3afSChuck Lever #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 88555ee3afSChuck Lever 89555ee3afSChuck Lever #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 901da177e4SLinus Torvalds 9112a80469SChuck Lever /** 9281c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 9381c098afS\"Talpey, Thomas\ * @transport: transport to register 9481c098afS\"Talpey, Thomas\ * 9581c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 9681c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 9781c098afS\"Talpey, Thomas\ * 9881c098afS\"Talpey, Thomas\ * Returns: 9981c098afS\"Talpey, Thomas\ * 0: transport successfully registered 10081c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 10181c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 10281c098afS\"Talpey, Thomas\ */ 10381c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 10481c098afS\"Talpey, Thomas\ { 10581c098afS\"Talpey, Thomas\ struct xprt_class *t; 10681c098afS\"Talpey, Thomas\ int result; 10781c098afS\"Talpey, Thomas\ 10881c098afS\"Talpey, Thomas\ result = -EEXIST; 10981c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 11081c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 11181c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 1124fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 11381c098afS\"Talpey, Thomas\ goto out; 11481c098afS\"Talpey, Thomas\ } 11581c098afS\"Talpey, Thomas\ 11681c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 11781c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 11881c098afS\"Talpey, Thomas\ transport->name); 11981c098afS\"Talpey, Thomas\ result = 0; 12081c098afS\"Talpey, Thomas\ 12181c098afS\"Talpey, Thomas\ out: 12281c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 12381c098afS\"Talpey, Thomas\ return result; 12481c098afS\"Talpey, Thomas\ } 12581c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 12681c098afS\"Talpey, Thomas\ 12781c098afS\"Talpey, Thomas\ /** 12881c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 12965b6e42cSRandy Dunlap * @transport: transport to unregister 13081c098afS\"Talpey, Thomas\ * 13181c098afS\"Talpey, Thomas\ * Returns: 13281c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 13381c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 13481c098afS\"Talpey, Thomas\ */ 13581c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 13681c098afS\"Talpey, Thomas\ { 13781c098afS\"Talpey, Thomas\ struct xprt_class *t; 13881c098afS\"Talpey, Thomas\ int result; 13981c098afS\"Talpey, Thomas\ 14081c098afS\"Talpey, Thomas\ result = 0; 14181c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 14281c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 14381c098afS\"Talpey, Thomas\ if (t == transport) { 14481c098afS\"Talpey, Thomas\ printk(KERN_INFO 14581c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 14681c098afS\"Talpey, Thomas\ transport->name); 14781c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 14881c098afS\"Talpey, Thomas\ goto out; 14981c098afS\"Talpey, Thomas\ } 15081c098afS\"Talpey, Thomas\ } 15181c098afS\"Talpey, Thomas\ result = -ENOENT; 15281c098afS\"Talpey, Thomas\ 15381c098afS\"Talpey, Thomas\ out: 15481c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 15581c098afS\"Talpey, Thomas\ return result; 15681c098afS\"Talpey, Thomas\ } 15781c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 15881c098afS\"Talpey, Thomas\ 15981c098afS\"Talpey, Thomas\ /** 160441e3e24STom Talpey * xprt_load_transport - load a transport implementation 161441e3e24STom Talpey * @transport_name: transport to load 162441e3e24STom Talpey * 163441e3e24STom Talpey * Returns: 164441e3e24STom Talpey * 0: transport successfully loaded 165441e3e24STom Talpey * -ENOENT: transport module not available 166441e3e24STom Talpey */ 167441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 168441e3e24STom Talpey { 169441e3e24STom Talpey struct xprt_class *t; 170441e3e24STom Talpey int result; 171441e3e24STom Talpey 172441e3e24STom Talpey result = 0; 173441e3e24STom Talpey spin_lock(&xprt_list_lock); 174441e3e24STom Talpey list_for_each_entry(t, &xprt_list, list) { 175441e3e24STom Talpey if (strcmp(t->name, transport_name) == 0) { 176441e3e24STom Talpey spin_unlock(&xprt_list_lock); 177441e3e24STom Talpey goto out; 178441e3e24STom Talpey } 179441e3e24STom Talpey } 180441e3e24STom Talpey spin_unlock(&xprt_list_lock); 181ef7ffe8fSAlex Riesen result = request_module("xprt%s", transport_name); 182441e3e24STom Talpey out: 183441e3e24STom Talpey return result; 184441e3e24STom Talpey } 185441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 186441e3e24STom Talpey 187441e3e24STom Talpey /** 18812a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 18912a80469SChuck Lever * @task: task that is requesting access to the transport 19012a80469SChuck Lever * 19112a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 19212a80469SChuck Lever * transport connects from colliding with writes. No congestion control 19312a80469SChuck Lever * is provided. 1941da177e4SLinus Torvalds */ 19543cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 1961da177e4SLinus Torvalds { 19712a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 19834006ceeSTrond Myklebust int priority; 19912a80469SChuck Lever 20012a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 20112a80469SChuck Lever if (task == xprt->snd_task) 20212a80469SChuck Lever return 1; 20312a80469SChuck Lever goto out_sleep; 20412a80469SChuck Lever } 20512a80469SChuck Lever xprt->snd_task = task; 20643cedbf0STrond Myklebust if (req != NULL) { 20712a80469SChuck Lever req->rq_bytes_sent = 0; 20812a80469SChuck Lever req->rq_ntrans++; 20943cedbf0STrond Myklebust } 2104d4a76f3Sj223yang@asset.uwaterloo.ca 21112a80469SChuck Lever return 1; 21212a80469SChuck Lever 21312a80469SChuck Lever out_sleep: 21446121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", 21512a80469SChuck Lever task->tk_pid, xprt); 21612a80469SChuck Lever task->tk_timeout = 0; 21712a80469SChuck Lever task->tk_status = -EAGAIN; 21834006ceeSTrond Myklebust if (req == NULL) 21934006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 22034006ceeSTrond Myklebust else if (!req->rq_ntrans) 22134006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 22212a80469SChuck Lever else 22334006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 22434006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 22512a80469SChuck Lever return 0; 22612a80469SChuck Lever } 22712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 22812a80469SChuck Lever 229632e3bdcSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 230632e3bdcSTrond Myklebust { 231632e3bdcSTrond Myklebust xprt->snd_task = NULL; 232632e3bdcSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { 233632e3bdcSTrond Myklebust smp_mb__before_clear_bit(); 234632e3bdcSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 235632e3bdcSTrond Myklebust smp_mb__after_clear_bit(); 236632e3bdcSTrond Myklebust } else 237c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 238632e3bdcSTrond Myklebust } 239632e3bdcSTrond Myklebust 24012a80469SChuck Lever /* 24112a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 24212a80469SChuck Lever * @task: task that is requesting access to the transport 24312a80469SChuck Lever * 24412a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 24512a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 24612a80469SChuck Lever * woken up and given access to the transport. 24712a80469SChuck Lever */ 24843cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 24912a80469SChuck Lever { 2501da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 25134006ceeSTrond Myklebust int priority; 2521da177e4SLinus Torvalds 2532226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2541da177e4SLinus Torvalds if (task == xprt->snd_task) 2551da177e4SLinus Torvalds return 1; 2561da177e4SLinus Torvalds goto out_sleep; 2571da177e4SLinus Torvalds } 25843cedbf0STrond Myklebust if (req == NULL) { 25943cedbf0STrond Myklebust xprt->snd_task = task; 26043cedbf0STrond Myklebust return 1; 26143cedbf0STrond Myklebust } 26212a80469SChuck Lever if (__xprt_get_cong(xprt, task)) { 2631da177e4SLinus Torvalds xprt->snd_task = task; 2641da177e4SLinus Torvalds req->rq_bytes_sent = 0; 2651da177e4SLinus Torvalds req->rq_ntrans++; 2661da177e4SLinus Torvalds return 1; 2671da177e4SLinus Torvalds } 268632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2691da177e4SLinus Torvalds out_sleep: 27046121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 2711da177e4SLinus Torvalds task->tk_timeout = 0; 2721da177e4SLinus Torvalds task->tk_status = -EAGAIN; 27334006ceeSTrond Myklebust if (req == NULL) 27434006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 27534006ceeSTrond Myklebust else if (!req->rq_ntrans) 27634006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 2771da177e4SLinus Torvalds else 27834006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 27934006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 2801da177e4SLinus Torvalds return 0; 2811da177e4SLinus Torvalds } 28212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2831da177e4SLinus Torvalds 28412a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2851da177e4SLinus Torvalds { 2861da177e4SLinus Torvalds int retval; 2871da177e4SLinus Torvalds 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 29412a80469SChuck Lever static void __xprt_lock_write_next(struct rpc_xprt *xprt) 2951da177e4SLinus Torvalds { 2961da177e4SLinus Torvalds struct rpc_task *task; 29749e9a890SChuck Lever struct rpc_rqst *req; 29849e9a890SChuck Lever 29949e9a890SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 30049e9a890SChuck Lever return; 30149e9a890SChuck Lever 30249e9a890SChuck Lever task = rpc_wake_up_next(&xprt->sending); 30343cedbf0STrond Myklebust if (task == NULL) 30449e9a890SChuck Lever goto out_unlock; 30549e9a890SChuck Lever 30649e9a890SChuck Lever req = task->tk_rqstp; 30749e9a890SChuck Lever xprt->snd_task = task; 30849e9a890SChuck Lever if (req) { 30949e9a890SChuck Lever req->rq_bytes_sent = 0; 31049e9a890SChuck Lever req->rq_ntrans++; 31149e9a890SChuck Lever } 31249e9a890SChuck Lever return; 31349e9a890SChuck Lever 31449e9a890SChuck Lever out_unlock: 315632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 31649e9a890SChuck Lever } 31749e9a890SChuck Lever 31849e9a890SChuck Lever static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 31949e9a890SChuck Lever { 32049e9a890SChuck Lever struct rpc_task *task; 32143cedbf0STrond Myklebust struct rpc_rqst *req; 3221da177e4SLinus Torvalds 3232226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 3241da177e4SLinus Torvalds return; 32549e9a890SChuck Lever if (RPCXPRT_CONGESTED(xprt)) 3261da177e4SLinus Torvalds goto out_unlock; 3271da177e4SLinus Torvalds task = rpc_wake_up_next(&xprt->sending); 32843cedbf0STrond Myklebust if (task == NULL) 3291da177e4SLinus Torvalds goto out_unlock; 33043cedbf0STrond Myklebust 33143cedbf0STrond Myklebust req = task->tk_rqstp; 33243cedbf0STrond Myklebust if (req == NULL) { 3331da177e4SLinus Torvalds xprt->snd_task = task; 33443cedbf0STrond Myklebust return; 33543cedbf0STrond Myklebust } 33643cedbf0STrond Myklebust if (__xprt_get_cong(xprt, task)) { 33743cedbf0STrond Myklebust xprt->snd_task = task; 3381da177e4SLinus Torvalds req->rq_bytes_sent = 0; 3391da177e4SLinus Torvalds req->rq_ntrans++; 3401da177e4SLinus Torvalds return; 3411da177e4SLinus Torvalds } 3421da177e4SLinus Torvalds out_unlock: 343632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3441da177e4SLinus Torvalds } 3451da177e4SLinus Torvalds 34649e9a890SChuck Lever /** 34749e9a890SChuck Lever * xprt_release_xprt - 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. No congestion control is provided. 3521da177e4SLinus Torvalds */ 35349e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3541da177e4SLinus Torvalds { 3551da177e4SLinus Torvalds if (xprt->snd_task == task) { 356632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3571da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3581da177e4SLinus Torvalds } 3591da177e4SLinus Torvalds } 36012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3611da177e4SLinus Torvalds 36249e9a890SChuck Lever /** 36349e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 36449e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 36549e9a890SChuck Lever * @task: task that is releasing access to the transport 36649e9a890SChuck Lever * 36749e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 36849e9a890SChuck Lever * transport if the transport's congestion window allows it. 36949e9a890SChuck Lever */ 37049e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 37149e9a890SChuck Lever { 37249e9a890SChuck Lever if (xprt->snd_task == task) { 373632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 37449e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 37549e9a890SChuck Lever } 37649e9a890SChuck Lever } 37712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 37849e9a890SChuck Lever 37949e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3801da177e4SLinus Torvalds { 3814a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 38249e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3834a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3841da177e4SLinus Torvalds } 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds /* 3871da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3881da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3891da177e4SLinus Torvalds */ 3901da177e4SLinus Torvalds static int 3911da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 3921da177e4SLinus Torvalds { 3931da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3941da177e4SLinus Torvalds 3951da177e4SLinus Torvalds if (req->rq_cong) 3961da177e4SLinus Torvalds return 1; 39746121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 3981da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 3991da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 4001da177e4SLinus Torvalds return 0; 4011da177e4SLinus Torvalds req->rq_cong = 1; 4021da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 4031da177e4SLinus Torvalds return 1; 4041da177e4SLinus Torvalds } 4051da177e4SLinus Torvalds 4061da177e4SLinus Torvalds /* 4071da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4081da177e4SLinus Torvalds * that has been sleeping due to congestion 4091da177e4SLinus Torvalds */ 4101da177e4SLinus Torvalds static void 4111da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4121da177e4SLinus Torvalds { 4131da177e4SLinus Torvalds if (!req->rq_cong) 4141da177e4SLinus Torvalds return; 4151da177e4SLinus Torvalds req->rq_cong = 0; 4161da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 41749e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4181da177e4SLinus Torvalds } 4191da177e4SLinus Torvalds 42046c0ee8bSChuck Lever /** 421a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 422a58dd398SChuck Lever * @task: RPC request that recently completed 423a58dd398SChuck Lever * 424a58dd398SChuck Lever * Useful for transports that require congestion control. 425a58dd398SChuck Lever */ 426a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 427a58dd398SChuck Lever { 428a58dd398SChuck Lever __xprt_put_cong(task->tk_xprt, task->tk_rqstp); 429a58dd398SChuck Lever } 43012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 431a58dd398SChuck Lever 432a58dd398SChuck Lever /** 43346c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 43446c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 43546c0ee8bSChuck Lever * @result: result code of completed RPC request 43646c0ee8bSChuck Lever * 4371da177e4SLinus Torvalds * We use a time-smoothed congestion estimator to avoid heavy oscillation. 4381da177e4SLinus Torvalds */ 43946c0ee8bSChuck Lever void xprt_adjust_cwnd(struct rpc_task *task, int result) 4401da177e4SLinus Torvalds { 44146c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 44246c0ee8bSChuck Lever struct rpc_xprt *xprt = task->tk_xprt; 44346c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4441da177e4SLinus Torvalds 4451da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4461da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4471da177e4SLinus Torvalds * the result gets rounded properly. */ 4481da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4491da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4501da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 45149e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4521da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4531da177e4SLinus Torvalds cwnd >>= 1; 4541da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4551da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4561da177e4SLinus Torvalds } 4571da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4581da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4591da177e4SLinus Torvalds xprt->cwnd = cwnd; 46046c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4611da177e4SLinus Torvalds } 46212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4631da177e4SLinus Torvalds 46444fbac22SChuck Lever /** 46544fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 46644fbac22SChuck Lever * @xprt: transport with waiting tasks 46744fbac22SChuck Lever * @status: result code to plant in each task before waking it 46844fbac22SChuck Lever * 46944fbac22SChuck Lever */ 47044fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 47144fbac22SChuck Lever { 47244fbac22SChuck Lever if (status < 0) 47344fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 47444fbac22SChuck Lever else 47544fbac22SChuck Lever rpc_wake_up(&xprt->pending); 47644fbac22SChuck Lever } 47712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 47844fbac22SChuck Lever 479c7b2cae8SChuck Lever /** 480c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 481c7b2cae8SChuck Lever * @task: task to be put to sleep 4820b80ae42SRandy Dunlap * @action: function pointer to be executed after wait 483c7b2cae8SChuck Lever */ 484b6ddf64fSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) 485c7b2cae8SChuck Lever { 486c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 487c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 488c7b2cae8SChuck Lever 489c7b2cae8SChuck Lever task->tk_timeout = req->rq_timeout; 490b6ddf64fSTrond Myklebust rpc_sleep_on(&xprt->pending, task, action); 491c7b2cae8SChuck Lever } 49212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 493c7b2cae8SChuck Lever 494c7b2cae8SChuck Lever /** 495c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 496c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 497c7b2cae8SChuck Lever * 498c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 499c7b2cae8SChuck Lever */ 500c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 501c7b2cae8SChuck Lever { 502c7b2cae8SChuck Lever if (unlikely(xprt->shutdown)) 503c7b2cae8SChuck Lever return; 504c7b2cae8SChuck Lever 505c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 506c7b2cae8SChuck Lever if (xprt->snd_task) { 50746121cf7SChuck Lever dprintk("RPC: write space: waking waiting task on " 50846121cf7SChuck Lever "xprt %p\n", xprt); 509fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); 510c7b2cae8SChuck Lever } 511c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 512c7b2cae8SChuck Lever } 51312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 514c7b2cae8SChuck Lever 515fe3aca29SChuck Lever /** 516fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 517fe3aca29SChuck Lever * @task: task whose timeout is to be set 518fe3aca29SChuck Lever * 519fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 520fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 521fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 522fe3aca29SChuck Lever */ 523fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 524fe3aca29SChuck Lever { 525fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 526fe3aca29SChuck Lever } 52712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 528fe3aca29SChuck Lever 529fe3aca29SChuck Lever /* 530fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout 531fe3aca29SChuck Lever * @task: task whose timeout is to be set 532fe3aca29SChuck Lever * 533fe3aca29SChuck Lever * Set a request's retransmit timeout using the RTT estimator. 534fe3aca29SChuck Lever */ 535fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 536fe3aca29SChuck Lever { 537fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 538ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 539ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 540fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 541ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 542fe3aca29SChuck Lever 543fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 544fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 545fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 546fe3aca29SChuck Lever task->tk_timeout = max_timeout; 547fe3aca29SChuck Lever } 54812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 549fe3aca29SChuck Lever 5501da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5511da177e4SLinus Torvalds { 552ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5531da177e4SLinus Torvalds 5541da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5551da177e4SLinus Torvalds if (to->to_exponential) 5561da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5571da177e4SLinus Torvalds else 5581da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 5591da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 5601da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 5611da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 5621da177e4SLinus Torvalds } 5631da177e4SLinus Torvalds 5649903cd1cSChuck Lever /** 5659903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 5669903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 5679903cd1cSChuck Lever * 5681da177e4SLinus Torvalds */ 5691da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 5701da177e4SLinus Torvalds { 5711da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 572ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5731da177e4SLinus Torvalds int status = 0; 5741da177e4SLinus Torvalds 5751da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 5761da177e4SLinus Torvalds if (to->to_exponential) 5771da177e4SLinus Torvalds req->rq_timeout <<= 1; 5781da177e4SLinus Torvalds else 5791da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 5801da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 5811da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 5821da177e4SLinus Torvalds req->rq_retries++; 5831da177e4SLinus Torvalds } else { 5841da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 5851da177e4SLinus Torvalds req->rq_retries = 0; 5861da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5871da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 5884a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5891da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 5904a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5911da177e4SLinus Torvalds status = -ETIMEDOUT; 5921da177e4SLinus Torvalds } 5931da177e4SLinus Torvalds 5941da177e4SLinus Torvalds if (req->rq_timeout == 0) { 5951da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 5961da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 5971da177e4SLinus Torvalds } 5981da177e4SLinus Torvalds return status; 5991da177e4SLinus Torvalds } 6001da177e4SLinus Torvalds 60165f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 6021da177e4SLinus Torvalds { 60365f27f38SDavid Howells struct rpc_xprt *xprt = 60465f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 6051da177e4SLinus Torvalds 606a246b010SChuck Lever xprt->ops->close(xprt); 60766af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 6081da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 6091da177e4SLinus Torvalds } 6101da177e4SLinus Torvalds 6119903cd1cSChuck Lever /** 61262da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6139903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6149903cd1cSChuck Lever * 6151da177e4SLinus Torvalds */ 61662da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6171da177e4SLinus Torvalds { 6181da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6194a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6201da177e4SLinus Torvalds xprt_clear_connected(xprt); 6212a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6224a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6231da177e4SLinus Torvalds } 62462da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6251da177e4SLinus Torvalds 62666af1e55STrond Myklebust /** 62766af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 62866af1e55STrond Myklebust * @xprt: transport to disconnect 62966af1e55STrond Myklebust * 63066af1e55STrond Myklebust */ 63166af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 63266af1e55STrond Myklebust { 63366af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 63466af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 63566af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 63666af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 63766af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 63866af1e55STrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6392a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 64066af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 64166af1e55STrond Myklebust } 64266af1e55STrond Myklebust 6437c1d71cfSTrond Myklebust /** 6447c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 6457c1d71cfSTrond Myklebust * @xprt: transport to disconnect 6467c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 6477c1d71cfSTrond Myklebust * 6487c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 6497c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 6507c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 6517c1d71cfSTrond Myklebust * a batch of RPC requests. 6527c1d71cfSTrond Myklebust * 6537c1d71cfSTrond Myklebust */ 6547c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 6557c1d71cfSTrond Myklebust { 6567c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 6577c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 6587c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 6597c1d71cfSTrond Myklebust goto out; 6607c1d71cfSTrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) 6617c1d71cfSTrond Myklebust goto out; 6627c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 6637c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 6647c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 6657c1d71cfSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6662a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6677c1d71cfSTrond Myklebust out: 6687c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 6697c1d71cfSTrond Myklebust } 6707c1d71cfSTrond Myklebust 6711da177e4SLinus Torvalds static void 6721da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 6731da177e4SLinus Torvalds { 6741da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 6751da177e4SLinus Torvalds 6764a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 6771da177e4SLinus Torvalds if (!list_empty(&xprt->recv) || xprt->shutdown) 6781da177e4SLinus Torvalds goto out_abort; 6792226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 6801da177e4SLinus Torvalds goto out_abort; 6814a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 682f75e6745STrond Myklebust set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); 683c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6841da177e4SLinus Torvalds return; 6851da177e4SLinus Torvalds out_abort: 6864a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 6871da177e4SLinus Torvalds } 6881da177e4SLinus Torvalds 6899903cd1cSChuck Lever /** 6909903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 6919903cd1cSChuck Lever * @task: RPC task that is requesting the connect 6921da177e4SLinus Torvalds * 6931da177e4SLinus Torvalds */ 6941da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 6951da177e4SLinus Torvalds { 6961da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 6971da177e4SLinus Torvalds 69846121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 6991da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 7001da177e4SLinus Torvalds 701ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 70201d37c42STrond Myklebust task->tk_status = -EAGAIN; 7031da177e4SLinus Torvalds return; 7041da177e4SLinus Torvalds } 7051da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 7061da177e4SLinus Torvalds return; 707feb8ca37STrond Myklebust 708feb8ca37STrond Myklebust if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) 709feb8ca37STrond Myklebust xprt->ops->close(xprt); 710feb8ca37STrond Myklebust 7111da177e4SLinus Torvalds if (xprt_connected(xprt)) 712a246b010SChuck Lever xprt_release_write(xprt, task); 713a246b010SChuck Lever else { 7141da177e4SLinus Torvalds if (task->tk_rqstp) 7151da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 7161da177e4SLinus Torvalds 717a8ce4a8fSTrond Myklebust task->tk_timeout = task->tk_rqstp->rq_timeout; 7185d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_connect_status); 7190b9e7943STrond Myklebust 7200b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 7210b9e7943STrond Myklebust return; 7220b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 7230b9e7943STrond Myklebust return; 724262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 725a246b010SChuck Lever xprt->ops->connect(task); 7261da177e4SLinus Torvalds } 7271da177e4SLinus Torvalds } 7281da177e4SLinus Torvalds 7299903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 7301da177e4SLinus Torvalds { 7311da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 7321da177e4SLinus Torvalds 733cd983ef8SChuck Lever if (task->tk_status == 0) { 734262ca07dSChuck Lever xprt->stat.connect_count++; 735262ca07dSChuck Lever xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; 73646121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connection established\n", 7371da177e4SLinus Torvalds task->tk_pid); 7381da177e4SLinus Torvalds return; 7391da177e4SLinus Torvalds } 7401da177e4SLinus Torvalds 7411da177e4SLinus Torvalds switch (task->tk_status) { 7422a491991STrond Myklebust case -EAGAIN: 7432a491991STrond Myklebust dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); 74423475d66SChuck Lever break; 7451da177e4SLinus Torvalds case -ETIMEDOUT: 74646121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connect attempt timed " 74746121cf7SChuck Lever "out\n", task->tk_pid); 7481da177e4SLinus Torvalds break; 7491da177e4SLinus Torvalds default: 75046121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: error %d connecting to " 75146121cf7SChuck Lever "server %s\n", task->tk_pid, -task->tk_status, 75246121cf7SChuck Lever task->tk_client->cl_server); 7531da177e4SLinus Torvalds xprt_release_write(xprt, task); 75423475d66SChuck Lever task->tk_status = -EIO; 75523475d66SChuck Lever } 7561da177e4SLinus Torvalds } 7571da177e4SLinus Torvalds 7589903cd1cSChuck Lever /** 7599903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 7609903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 7619903cd1cSChuck Lever * @xid: RPC XID of incoming reply 7629903cd1cSChuck Lever * 7631da177e4SLinus Torvalds */ 764d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 7651da177e4SLinus Torvalds { 7668f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 7671da177e4SLinus Torvalds 7688f3a6de3SPavel Emelyanov list_for_each_entry(entry, &xprt->recv, rq_list) 769262ca07dSChuck Lever if (entry->rq_xid == xid) 770262ca07dSChuck Lever return entry; 77146121cf7SChuck Lever 77246121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 77346121cf7SChuck Lever ntohl(xid)); 774262ca07dSChuck Lever xprt->stat.bad_xids++; 775262ca07dSChuck Lever return NULL; 7761da177e4SLinus Torvalds } 77712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 7781da177e4SLinus Torvalds 779bbc72ceaSChuck Lever static void xprt_update_rtt(struct rpc_task *task) 7801da177e4SLinus Torvalds { 7811570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 7821570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 7831da177e4SLinus Torvalds unsigned timer = task->tk_msg.rpc_proc->p_timer; 784d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 7851570c1e4SChuck Lever 7861da177e4SLinus Torvalds if (timer) { 7871da177e4SLinus Torvalds if (req->rq_ntrans == 1) 788ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 7891570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 7901da177e4SLinus Torvalds } 7911da177e4SLinus Torvalds } 7921da177e4SLinus Torvalds 7931570c1e4SChuck Lever /** 7941570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 7951570c1e4SChuck Lever * @task: RPC request that recently completed 7961570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 7971570c1e4SChuck Lever * 7981570c1e4SChuck Lever * Caller holds transport lock. 7991570c1e4SChuck Lever */ 8001570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 8011570c1e4SChuck Lever { 8021570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 803fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 8041da177e4SLinus Torvalds 8051570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 8061570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 8071da177e4SLinus Torvalds 808fda13939STrond Myklebust xprt->stat.recvs++; 809d60dbb20STrond Myklebust req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); 810bbc72ceaSChuck Lever if (xprt->ops->timer != NULL) 811bbc72ceaSChuck Lever xprt_update_rtt(task); 812ef759a2eSChuck Lever 8131da177e4SLinus Torvalds list_del_init(&req->rq_list); 8141e799b67STrond Myklebust req->rq_private_buf.len = copied; 815dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 816dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 81743ac3f29STrond Myklebust smp_wmb(); 818dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 819fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 8201da177e4SLinus Torvalds } 82112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 8221da177e4SLinus Torvalds 82346c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 8241da177e4SLinus Torvalds { 8251da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8261da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8271da177e4SLinus Torvalds 8285d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 8295d00837bSTrond Myklebust return; 83046121cf7SChuck Lever dprintk("RPC: %5u xprt_timer\n", task->tk_pid); 83146c0ee8bSChuck Lever 8325d00837bSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 833dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 83446c0ee8bSChuck Lever if (xprt->ops->timer) 83546c0ee8bSChuck Lever xprt->ops->timer(task); 8365d00837bSTrond Myklebust } else 8375d00837bSTrond Myklebust task->tk_status = 0; 8385d00837bSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 8391da177e4SLinus Torvalds } 8401da177e4SLinus Torvalds 8414cfc7e60SRahul Iyer static inline int xprt_has_timer(struct rpc_xprt *xprt) 8424cfc7e60SRahul Iyer { 8434cfc7e60SRahul Iyer return xprt->idle_timeout != 0; 8444cfc7e60SRahul Iyer } 8454cfc7e60SRahul Iyer 8469903cd1cSChuck Lever /** 8479903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 8489903cd1cSChuck Lever * @task: RPC task about to send a request 8499903cd1cSChuck Lever * 8501da177e4SLinus Torvalds */ 8519903cd1cSChuck Lever int xprt_prepare_transmit(struct rpc_task *task) 8521da177e4SLinus Torvalds { 8531da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8541da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8551da177e4SLinus Torvalds int err = 0; 8561da177e4SLinus Torvalds 85746121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 8581da177e4SLinus Torvalds 8594a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 860dd2b63d0SRicardo Labiaga if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) { 861dd2b63d0SRicardo Labiaga err = req->rq_reply_bytes_recvd; 8621da177e4SLinus Torvalds goto out_unlock; 8631da177e4SLinus Torvalds } 86443cedbf0STrond Myklebust if (!xprt->ops->reserve_xprt(xprt, task)) 8651da177e4SLinus Torvalds err = -EAGAIN; 8661da177e4SLinus Torvalds out_unlock: 8674a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 8681da177e4SLinus Torvalds return err; 8691da177e4SLinus Torvalds } 8701da177e4SLinus Torvalds 871e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 8725e5ce5beSTrond Myklebust { 873343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 8745e5ce5beSTrond Myklebust } 8755e5ce5beSTrond Myklebust 8769903cd1cSChuck Lever /** 8779903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 8789903cd1cSChuck Lever * @task: controlling RPC task 8799903cd1cSChuck Lever * 8809903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 8819903cd1cSChuck Lever */ 8829903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 8831da177e4SLinus Torvalds { 8841da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8851da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 886a246b010SChuck Lever int status; 8871da177e4SLinus Torvalds 88846121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 8891da177e4SLinus Torvalds 890dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 89155ae1aabSRicardo Labiaga if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { 89255ae1aabSRicardo Labiaga /* 89355ae1aabSRicardo Labiaga * Add to the list only if we're expecting a reply 89455ae1aabSRicardo Labiaga */ 8954a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 8961da177e4SLinus Torvalds /* Update the softirq receive buffer */ 8971da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 8981da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 8991da177e4SLinus Torvalds /* Add request to the receive list */ 9001da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 9014a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9021da177e4SLinus Torvalds xprt_reset_majortimeo(req); 9030f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 9040f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 9051da177e4SLinus Torvalds } 9061da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 9071da177e4SLinus Torvalds return; 9081da177e4SLinus Torvalds 9097c1d71cfSTrond Myklebust req->rq_connect_cookie = xprt->connect_cookie; 910ff839970SChuck Lever req->rq_xtime = ktime_get(); 911a246b010SChuck Lever status = xprt->ops->send_request(task); 912c8485e4dSTrond Myklebust if (status != 0) { 913c8485e4dSTrond Myklebust task->tk_status = status; 914c8485e4dSTrond Myklebust return; 915c8485e4dSTrond Myklebust } 916c8485e4dSTrond Myklebust 91746121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 918468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 919fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 920262ca07dSChuck Lever 921fe3aca29SChuck Lever xprt->ops->set_retrans_timeout(task); 922262ca07dSChuck Lever 923262ca07dSChuck Lever xprt->stat.sends++; 924262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 925262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 926262ca07dSChuck Lever 927fe3aca29SChuck Lever /* Don't race with disconnect */ 928fe3aca29SChuck Lever if (!xprt_connected(xprt)) 929fe3aca29SChuck Lever task->tk_status = -ENOTCONN; 930dd2b63d0SRicardo Labiaga else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) { 93155ae1aabSRicardo Labiaga /* 93255ae1aabSRicardo Labiaga * Sleep on the pending queue since 93355ae1aabSRicardo Labiaga * we're expecting a reply. 93455ae1aabSRicardo Labiaga */ 9355d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 93655ae1aabSRicardo Labiaga } 937fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9381da177e4SLinus Torvalds } 9391da177e4SLinus Torvalds 940d9ba131dSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) 941d9ba131dSTrond Myklebust { 942d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 943d9ba131dSTrond Myklebust 944d9ba131dSTrond Myklebust if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) 945d9ba131dSTrond Myklebust goto out; 946d9ba131dSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); 947d9ba131dSTrond Myklebust if (req != NULL) 948d9ba131dSTrond Myklebust goto out; 949d9ba131dSTrond Myklebust atomic_dec(&xprt->num_reqs); 950d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 951d9ba131dSTrond Myklebust out: 952d9ba131dSTrond Myklebust return req; 953d9ba131dSTrond Myklebust } 954d9ba131dSTrond Myklebust 955d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 956d9ba131dSTrond Myklebust { 957d9ba131dSTrond Myklebust if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { 958d9ba131dSTrond Myklebust kfree(req); 959d9ba131dSTrond Myklebust return true; 960d9ba131dSTrond Myklebust } 961d9ba131dSTrond Myklebust return false; 962d9ba131dSTrond Myklebust } 963d9ba131dSTrond Myklebust 964ee5ebe85STrond Myklebust static void xprt_alloc_slot(struct rpc_task *task) 9651da177e4SLinus Torvalds { 9661da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 967d9ba131dSTrond Myklebust struct rpc_rqst *req; 9681da177e4SLinus Torvalds 9691da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 970d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 971d9ba131dSTrond Myklebust list_del(&req->rq_list); 972d9ba131dSTrond Myklebust goto out_init_req; 973d9ba131dSTrond Myklebust } 974d9ba131dSTrond Myklebust req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT); 975d9ba131dSTrond Myklebust if (!IS_ERR(req)) 976d9ba131dSTrond Myklebust goto out_init_req; 977d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 978d9ba131dSTrond Myklebust case -ENOMEM: 979d9ba131dSTrond Myklebust rpc_delay(task, HZ >> 2); 980d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 981d9ba131dSTrond Myklebust "failed! Retrying\n"); 982d9ba131dSTrond Myklebust break; 983d9ba131dSTrond Myklebust case -EAGAIN: 984d9ba131dSTrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 985d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 986d9ba131dSTrond Myklebust } 987d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 988d9ba131dSTrond Myklebust return; 989d9ba131dSTrond Myklebust out_init_req: 990d9ba131dSTrond Myklebust task->tk_status = 0; 9911da177e4SLinus Torvalds task->tk_rqstp = req; 9921da177e4SLinus Torvalds xprt_request_init(task, xprt); 9931da177e4SLinus Torvalds } 9941da177e4SLinus Torvalds 995ee5ebe85STrond Myklebust static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 996ee5ebe85STrond Myklebust { 997d9ba131dSTrond Myklebust if (xprt_dynamic_free_slot(xprt, req)) 998d9ba131dSTrond Myklebust return; 999d9ba131dSTrond Myklebust 1000ee5ebe85STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1001ee5ebe85STrond Myklebust 1002ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1003ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1004ee5ebe85STrond Myklebust rpc_wake_up_next(&xprt->backlog); 1005ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1006ee5ebe85STrond Myklebust } 1007ee5ebe85STrond Myklebust 100821de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 100921de0a95STrond Myklebust { 101021de0a95STrond Myklebust struct rpc_rqst *req; 101121de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 101221de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 101321de0a95STrond Myklebust list_del(&req->rq_list); 101421de0a95STrond Myklebust kfree(req); 101521de0a95STrond Myklebust } 101621de0a95STrond Myklebust } 101721de0a95STrond Myklebust 1018d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1019d9ba131dSTrond Myklebust unsigned int num_prealloc, 1020d9ba131dSTrond Myklebust unsigned int max_alloc) 1021bd1722d4SPavel Emelyanov { 1022bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 102321de0a95STrond Myklebust struct rpc_rqst *req; 102421de0a95STrond Myklebust int i; 1025bd1722d4SPavel Emelyanov 1026bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1027bd1722d4SPavel Emelyanov if (xprt == NULL) 1028bd1722d4SPavel Emelyanov goto out; 1029bd1722d4SPavel Emelyanov 103021de0a95STrond Myklebust xprt_init(xprt, net); 103121de0a95STrond Myklebust 103221de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 103321de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 103421de0a95STrond Myklebust if (!req) 103521de0a95STrond Myklebust break; 103621de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 103721de0a95STrond Myklebust } 103821de0a95STrond Myklebust if (i < num_prealloc) 1039bd1722d4SPavel Emelyanov goto out_free; 1040d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1041d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1042d9ba131dSTrond Myklebust else 104321de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1044d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1045d9ba131dSTrond Myklebust atomic_set(&xprt->num_reqs, num_prealloc); 1046bd1722d4SPavel Emelyanov 1047bd1722d4SPavel Emelyanov return xprt; 1048bd1722d4SPavel Emelyanov 1049bd1722d4SPavel Emelyanov out_free: 105021de0a95STrond Myklebust xprt_free(xprt); 1051bd1722d4SPavel Emelyanov out: 1052bd1722d4SPavel Emelyanov return NULL; 1053bd1722d4SPavel Emelyanov } 1054bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1055bd1722d4SPavel Emelyanov 1056e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1057e204e621SPavel Emelyanov { 105837aa2133SPavel Emelyanov put_net(xprt->xprt_net); 105921de0a95STrond Myklebust xprt_free_all_slots(xprt); 1060e204e621SPavel Emelyanov kfree(xprt); 1061e204e621SPavel Emelyanov } 1062e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1063e204e621SPavel Emelyanov 10649903cd1cSChuck Lever /** 10659903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 10669903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 10679903cd1cSChuck Lever * 10689903cd1cSChuck Lever * If no more slots are available, place the task on the transport's 10699903cd1cSChuck Lever * backlog queue. 10709903cd1cSChuck Lever */ 10719903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 10721da177e4SLinus Torvalds { 10731da177e4SLinus Torvalds struct rpc_xprt *xprt = task->tk_xprt; 10741da177e4SLinus Torvalds 107543cedbf0STrond Myklebust task->tk_status = 0; 107643cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 107743cedbf0STrond Myklebust return; 107843cedbf0STrond Myklebust 107943cedbf0STrond Myklebust /* Note: grabbing the xprt_lock_write() here is not strictly needed, 108043cedbf0STrond Myklebust * but ensures that we throttle new slot allocation if the transport 108143cedbf0STrond Myklebust * is congested (e.g. if reconnecting or if we're out of socket 108243cedbf0STrond Myklebust * write buffer space). 108343cedbf0STrond Myklebust */ 108443cedbf0STrond Myklebust task->tk_timeout = 0; 108543cedbf0STrond Myklebust task->tk_status = -EAGAIN; 108643cedbf0STrond Myklebust if (!xprt_lock_write(xprt, task)) 108743cedbf0STrond Myklebust return; 108843cedbf0STrond Myklebust 10895dc07727SChuck Lever spin_lock(&xprt->reserve_lock); 1090ee5ebe85STrond Myklebust xprt_alloc_slot(task); 10915dc07727SChuck Lever spin_unlock(&xprt->reserve_lock); 109243cedbf0STrond Myklebust xprt_release_write(xprt, task); 10931da177e4SLinus Torvalds } 10941da177e4SLinus Torvalds 1095d8ed029dSAlexey Dobriyan static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) 10961da177e4SLinus Torvalds { 10970eae88f3SEric Dumazet return (__force __be32)xprt->xid++; 10981da177e4SLinus Torvalds } 10991da177e4SLinus Torvalds 11001da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 11011da177e4SLinus Torvalds { 1102bf3fcf89SChuck Lever xprt->xid = net_random(); 11031da177e4SLinus Torvalds } 11041da177e4SLinus Torvalds 11059903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 11061da177e4SLinus Torvalds { 11071da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 11081da177e4SLinus Torvalds 1109d9ba131dSTrond Myklebust INIT_LIST_HEAD(&req->rq_list); 1110ba7392bbSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 11111da177e4SLinus Torvalds req->rq_task = task; 11121da177e4SLinus Torvalds req->rq_xprt = xprt; 111302107148SChuck Lever req->rq_buffer = NULL; 11141da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 1115ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf = NULL; 1116da45828eSTrond Myklebust xprt_reset_majortimeo(req); 111746121cf7SChuck Lever dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 11181da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 11191da177e4SLinus Torvalds } 11201da177e4SLinus Torvalds 11219903cd1cSChuck Lever /** 11229903cd1cSChuck Lever * xprt_release - release an RPC request slot 11239903cd1cSChuck Lever * @task: task which is finished with the slot 11249903cd1cSChuck Lever * 11251da177e4SLinus Torvalds */ 11269903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 11271da177e4SLinus Torvalds { 112855ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 11291da177e4SLinus Torvalds struct rpc_rqst *req; 11301da177e4SLinus Torvalds 11311da177e4SLinus Torvalds if (!(req = task->tk_rqstp)) 11321da177e4SLinus Torvalds return; 113355ae1aabSRicardo Labiaga 113455ae1aabSRicardo Labiaga xprt = req->rq_xprt; 113511c556b3SChuck Lever rpc_count_iostats(task); 11364a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 113749e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1138a58dd398SChuck Lever if (xprt->ops->release_request) 1139a58dd398SChuck Lever xprt->ops->release_request(task); 11401da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 11411da177e4SLinus Torvalds list_del(&req->rq_list); 11421da177e4SLinus Torvalds xprt->last_used = jiffies; 11434cfc7e60SRahul Iyer if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) 1144a246b010SChuck Lever mod_timer(&xprt->timer, 114503bf4b70SChuck Lever xprt->last_used + xprt->idle_timeout); 11464a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1147ee5ebe85STrond Myklebust if (req->rq_buffer) 1148c5a4dd8bSChuck Lever xprt->ops->buf_free(req->rq_buffer); 1149a17c2153STrond Myklebust if (req->rq_cred != NULL) 1150a17c2153STrond Myklebust put_rpccred(req->rq_cred); 11511da177e4SLinus Torvalds task->tk_rqstp = NULL; 1152ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1153ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 115455ae1aabSRicardo Labiaga 115546121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 1156ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1157ee5ebe85STrond Myklebust xprt_free_slot(xprt, req); 1158ee5ebe85STrond Myklebust else 1159c9acb42eSTrond Myklebust xprt_free_bc_request(req); 11601da177e4SLinus Torvalds } 11611da177e4SLinus Torvalds 116221de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1163c2866763SChuck Lever { 116421de0a95STrond Myklebust atomic_set(&xprt->count, 1); 1165c2866763SChuck Lever 1166c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1167c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 1168c2866763SChuck Lever 1169c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 1170c2866763SChuck Lever INIT_LIST_HEAD(&xprt->recv); 11719e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1172f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1173f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 11749e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1175f9acac1aSRicardo Labiaga 1176c2866763SChuck Lever xprt->last_used = jiffies; 1177c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1178a509050bSChuck Lever xprt->bind_index = 0; 1179c2866763SChuck Lever 1180c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1181c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 118234006ceeSTrond Myklebust rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); 1183c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1184c2866763SChuck Lever 1185c2866763SChuck Lever xprt_init_xid(xprt); 1186c2866763SChuck Lever 118721de0a95STrond Myklebust xprt->xprt_net = get_net(net); 11888d9266ffSTrond Myklebust } 11898d9266ffSTrond Myklebust 11908d9266ffSTrond Myklebust /** 11918d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 11928d9266ffSTrond Myklebust * @args: rpc transport creation arguments 11938d9266ffSTrond Myklebust * 11948d9266ffSTrond Myklebust */ 11958d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 11968d9266ffSTrond Myklebust { 11978d9266ffSTrond Myklebust struct rpc_xprt *xprt; 11988d9266ffSTrond Myklebust struct xprt_class *t; 11998d9266ffSTrond Myklebust 12008d9266ffSTrond Myklebust spin_lock(&xprt_list_lock); 12018d9266ffSTrond Myklebust list_for_each_entry(t, &xprt_list, list) { 12028d9266ffSTrond Myklebust if (t->ident == args->ident) { 12038d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 12048d9266ffSTrond Myklebust goto found; 12058d9266ffSTrond Myklebust } 12068d9266ffSTrond Myklebust } 12078d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 12088d9266ffSTrond Myklebust printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); 12098d9266ffSTrond Myklebust return ERR_PTR(-EIO); 12108d9266ffSTrond Myklebust 12118d9266ffSTrond Myklebust found: 12128d9266ffSTrond Myklebust xprt = t->setup(args); 12138d9266ffSTrond Myklebust if (IS_ERR(xprt)) { 12148d9266ffSTrond Myklebust dprintk("RPC: xprt_create_transport: failed, %ld\n", 12158d9266ffSTrond Myklebust -PTR_ERR(xprt)); 121621de0a95STrond Myklebust goto out; 12178d9266ffSTrond Myklebust } 121821de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 121921de0a95STrond Myklebust if (xprt_has_timer(xprt)) 122021de0a95STrond Myklebust setup_timer(&xprt->timer, xprt_init_autodisconnect, 122121de0a95STrond Myklebust (unsigned long)xprt); 122221de0a95STrond Myklebust else 122321de0a95STrond Myklebust init_timer(&xprt->timer); 1224c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1225c2866763SChuck Lever xprt->max_reqs); 122621de0a95STrond Myklebust out: 1227c2866763SChuck Lever return xprt; 1228c2866763SChuck Lever } 1229c2866763SChuck Lever 12309903cd1cSChuck Lever /** 12319903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 1232a8de240aSTrond Myklebust * @xprt: transport to destroy 12339903cd1cSChuck Lever * 12341da177e4SLinus Torvalds */ 1235a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 12361da177e4SLinus Torvalds { 12371da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 12380065db32STrond Myklebust xprt->shutdown = 1; 12390065db32STrond Myklebust del_timer_sync(&xprt->timer); 1240c8541ecdSChuck Lever 1241f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1242f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1243f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1244f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1245c3ae62aeSJ. Bruce Fields cancel_work_sync(&xprt->task_cleanup); 1246c8541ecdSChuck Lever /* 1247c8541ecdSChuck Lever * Tear down transport state and free the rpc_xprt 1248c8541ecdSChuck Lever */ 1249a246b010SChuck Lever xprt->ops->destroy(xprt); 12506b6ca86bSTrond Myklebust } 12511da177e4SLinus Torvalds 12526b6ca86bSTrond Myklebust /** 12536b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 12546b6ca86bSTrond Myklebust * @xprt: pointer to the transport 12556b6ca86bSTrond Myklebust * 12566b6ca86bSTrond Myklebust */ 12576b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 12586b6ca86bSTrond Myklebust { 1259a8de240aSTrond Myklebust if (atomic_dec_and_test(&xprt->count)) 1260a8de240aSTrond Myklebust xprt_destroy(xprt); 12616b6ca86bSTrond Myklebust } 12626b6ca86bSTrond Myklebust 12636b6ca86bSTrond Myklebust /** 12646b6ca86bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 12656b6ca86bSTrond Myklebust * @xprt: pointer to the transport 12666b6ca86bSTrond Myklebust * 12676b6ca86bSTrond Myklebust */ 12686b6ca86bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 12696b6ca86bSTrond Myklebust { 1270a8de240aSTrond Myklebust if (atomic_inc_not_zero(&xprt->count)) 12716b6ca86bSTrond Myklebust return xprt; 1272a8de240aSTrond Myklebust return NULL; 12731da177e4SLinus Torvalds } 1274