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 523705ad64SJeff Layton #include <trace/events/sunrpc.h> 533705ad64SJeff Layton 5455ae1aabSRicardo Labiaga #include "sunrpc.h" 5555ae1aabSRicardo Labiaga 561da177e4SLinus Torvalds /* 571da177e4SLinus Torvalds * Local variables 581da177e4SLinus Torvalds */ 591da177e4SLinus Torvalds 60f895b252SJeff Layton #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 611da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 621da177e4SLinus Torvalds #endif 631da177e4SLinus Torvalds 641da177e4SLinus Torvalds /* 651da177e4SLinus Torvalds * Local functions 661da177e4SLinus Torvalds */ 6721de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 681da177e4SLinus Torvalds static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); 691da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 701da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 7129807318SNeil Brown static void __xprt_put_cong(struct rpc_xprt *, struct rpc_rqst *); 724e0038b6STrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt); 731da177e4SLinus Torvalds 745ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7581c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7681c098afS\"Talpey, Thomas\ 7712a80469SChuck Lever /** 7881c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 7981c098afS\"Talpey, Thomas\ * @transport: transport to register 8081c098afS\"Talpey, Thomas\ * 8181c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 8281c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 8381c098afS\"Talpey, Thomas\ * 8481c098afS\"Talpey, Thomas\ * Returns: 8581c098afS\"Talpey, Thomas\ * 0: transport successfully registered 8681c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 8781c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 8881c098afS\"Talpey, Thomas\ */ 8981c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 9081c098afS\"Talpey, Thomas\ { 9181c098afS\"Talpey, Thomas\ struct xprt_class *t; 9281c098afS\"Talpey, Thomas\ int result; 9381c098afS\"Talpey, Thomas\ 9481c098afS\"Talpey, Thomas\ result = -EEXIST; 9581c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 9681c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 9781c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 984fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 9981c098afS\"Talpey, Thomas\ goto out; 10081c098afS\"Talpey, Thomas\ } 10181c098afS\"Talpey, Thomas\ 10281c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 10381c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 10481c098afS\"Talpey, Thomas\ transport->name); 10581c098afS\"Talpey, Thomas\ result = 0; 10681c098afS\"Talpey, Thomas\ 10781c098afS\"Talpey, Thomas\ out: 10881c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 10981c098afS\"Talpey, Thomas\ return result; 11081c098afS\"Talpey, Thomas\ } 11181c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 11281c098afS\"Talpey, Thomas\ 11381c098afS\"Talpey, Thomas\ /** 11481c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 11565b6e42cSRandy Dunlap * @transport: transport to unregister 11681c098afS\"Talpey, Thomas\ * 11781c098afS\"Talpey, Thomas\ * Returns: 11881c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 11981c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 12081c098afS\"Talpey, Thomas\ */ 12181c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 12281c098afS\"Talpey, Thomas\ { 12381c098afS\"Talpey, Thomas\ struct xprt_class *t; 12481c098afS\"Talpey, Thomas\ int result; 12581c098afS\"Talpey, Thomas\ 12681c098afS\"Talpey, Thomas\ result = 0; 12781c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 12881c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 12981c098afS\"Talpey, Thomas\ if (t == transport) { 13081c098afS\"Talpey, Thomas\ printk(KERN_INFO 13181c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 13281c098afS\"Talpey, Thomas\ transport->name); 13381c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 13481c098afS\"Talpey, Thomas\ goto out; 13581c098afS\"Talpey, Thomas\ } 13681c098afS\"Talpey, Thomas\ } 13781c098afS\"Talpey, Thomas\ result = -ENOENT; 13881c098afS\"Talpey, Thomas\ 13981c098afS\"Talpey, Thomas\ out: 14081c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 14181c098afS\"Talpey, Thomas\ return result; 14281c098afS\"Talpey, Thomas\ } 14381c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 14481c098afS\"Talpey, Thomas\ 14581c098afS\"Talpey, Thomas\ /** 146441e3e24STom Talpey * xprt_load_transport - load a transport implementation 147441e3e24STom Talpey * @transport_name: transport to load 148441e3e24STom Talpey * 149441e3e24STom Talpey * Returns: 150441e3e24STom Talpey * 0: transport successfully loaded 151441e3e24STom Talpey * -ENOENT: transport module not available 152441e3e24STom Talpey */ 153441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 154441e3e24STom Talpey { 155441e3e24STom Talpey struct xprt_class *t; 156441e3e24STom Talpey int result; 157441e3e24STom Talpey 158441e3e24STom Talpey result = 0; 159441e3e24STom Talpey spin_lock(&xprt_list_lock); 160441e3e24STom Talpey list_for_each_entry(t, &xprt_list, list) { 161441e3e24STom Talpey if (strcmp(t->name, transport_name) == 0) { 162441e3e24STom Talpey spin_unlock(&xprt_list_lock); 163441e3e24STom Talpey goto out; 164441e3e24STom Talpey } 165441e3e24STom Talpey } 166441e3e24STom Talpey spin_unlock(&xprt_list_lock); 167ef7ffe8fSAlex Riesen result = request_module("xprt%s", transport_name); 168441e3e24STom Talpey out: 169441e3e24STom Talpey return result; 170441e3e24STom Talpey } 171441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 172441e3e24STom Talpey 173441e3e24STom Talpey /** 17412a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 17512a80469SChuck Lever * @task: task that is requesting access to the transport 176177c27bfSRandy Dunlap * @xprt: pointer to the target transport 17712a80469SChuck Lever * 17812a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 17912a80469SChuck Lever * transport connects from colliding with writes. No congestion control 18012a80469SChuck Lever * is provided. 1811da177e4SLinus Torvalds */ 18243cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 1831da177e4SLinus Torvalds { 18412a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 18534006ceeSTrond Myklebust int priority; 18612a80469SChuck Lever 18712a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 18812a80469SChuck Lever if (task == xprt->snd_task) 18912a80469SChuck Lever return 1; 19012a80469SChuck Lever goto out_sleep; 19112a80469SChuck Lever } 19212a80469SChuck Lever xprt->snd_task = task; 19392551948STrond Myklebust if (req != NULL) 19412a80469SChuck Lever req->rq_ntrans++; 1954d4a76f3Sj223yang@asset.uwaterloo.ca 19612a80469SChuck Lever return 1; 19712a80469SChuck Lever 19812a80469SChuck Lever out_sleep: 19946121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", 20012a80469SChuck Lever task->tk_pid, xprt); 20112a80469SChuck Lever task->tk_timeout = 0; 20212a80469SChuck Lever task->tk_status = -EAGAIN; 20334006ceeSTrond Myklebust if (req == NULL) 20434006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 20534006ceeSTrond Myklebust else if (!req->rq_ntrans) 20634006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 20712a80469SChuck Lever else 20834006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 20934006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 21012a80469SChuck Lever return 0; 21112a80469SChuck Lever } 21212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 21312a80469SChuck Lever 214632e3bdcSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 215632e3bdcSTrond Myklebust { 216632e3bdcSTrond Myklebust xprt->snd_task = NULL; 217d19751e7STrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 2184e857c58SPeter Zijlstra smp_mb__before_atomic(); 219632e3bdcSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 2204e857c58SPeter Zijlstra smp_mb__after_atomic(); 221632e3bdcSTrond Myklebust } else 222c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 223632e3bdcSTrond Myklebust } 224632e3bdcSTrond Myklebust 22512a80469SChuck Lever /* 22612a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 22712a80469SChuck Lever * @task: task that is requesting access to the transport 22812a80469SChuck Lever * 22912a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 23012a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 23112a80469SChuck Lever * woken up and given access to the transport. 23212a80469SChuck Lever */ 23343cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 23412a80469SChuck Lever { 2351da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 23634006ceeSTrond Myklebust int priority; 2371da177e4SLinus Torvalds 2382226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2391da177e4SLinus Torvalds if (task == xprt->snd_task) 2401da177e4SLinus Torvalds return 1; 2411da177e4SLinus Torvalds goto out_sleep; 2421da177e4SLinus Torvalds } 24343cedbf0STrond Myklebust if (req == NULL) { 24443cedbf0STrond Myklebust xprt->snd_task = task; 24543cedbf0STrond Myklebust return 1; 24643cedbf0STrond Myklebust } 24712a80469SChuck Lever if (__xprt_get_cong(xprt, task)) { 2481da177e4SLinus Torvalds xprt->snd_task = task; 2491da177e4SLinus Torvalds req->rq_ntrans++; 2501da177e4SLinus Torvalds return 1; 2511da177e4SLinus Torvalds } 252632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2531da177e4SLinus Torvalds out_sleep: 25429807318SNeil Brown if (req) 25529807318SNeil Brown __xprt_put_cong(xprt, req); 25646121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 2571da177e4SLinus Torvalds task->tk_timeout = 0; 2581da177e4SLinus Torvalds task->tk_status = -EAGAIN; 25934006ceeSTrond Myklebust if (req == NULL) 26034006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 26134006ceeSTrond Myklebust else if (!req->rq_ntrans) 26234006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 2631da177e4SLinus Torvalds else 26434006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 26534006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 2661da177e4SLinus Torvalds return 0; 2671da177e4SLinus Torvalds } 26812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2691da177e4SLinus Torvalds 27012a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2711da177e4SLinus Torvalds { 2721da177e4SLinus Torvalds int retval; 2731da177e4SLinus Torvalds 2744a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 27543cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 2764a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2771da177e4SLinus Torvalds return retval; 2781da177e4SLinus Torvalds } 2791da177e4SLinus Torvalds 280961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 2811da177e4SLinus Torvalds { 282961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 28349e9a890SChuck Lever struct rpc_rqst *req; 28449e9a890SChuck Lever 28549e9a890SChuck Lever req = task->tk_rqstp; 28649e9a890SChuck Lever xprt->snd_task = task; 28792551948STrond Myklebust if (req) 28849e9a890SChuck Lever req->rq_ntrans++; 289961a828dSTrond Myklebust return true; 290961a828dSTrond Myklebust } 291961a828dSTrond Myklebust 292961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 293961a828dSTrond Myklebust { 294961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 29549e9a890SChuck Lever return; 29649e9a890SChuck Lever 297961a828dSTrond Myklebust if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt)) 298961a828dSTrond Myklebust return; 299632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 30049e9a890SChuck Lever } 30149e9a890SChuck Lever 302961a828dSTrond Myklebust static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) 30349e9a890SChuck Lever { 304961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 30543cedbf0STrond Myklebust struct rpc_rqst *req; 3061da177e4SLinus Torvalds 30743cedbf0STrond Myklebust req = task->tk_rqstp; 30843cedbf0STrond Myklebust if (req == NULL) { 3091da177e4SLinus Torvalds xprt->snd_task = task; 310961a828dSTrond Myklebust return true; 31143cedbf0STrond Myklebust } 31243cedbf0STrond Myklebust if (__xprt_get_cong(xprt, task)) { 31343cedbf0STrond Myklebust xprt->snd_task = task; 3141da177e4SLinus Torvalds req->rq_ntrans++; 315961a828dSTrond Myklebust return true; 3161da177e4SLinus Torvalds } 317961a828dSTrond Myklebust return false; 318961a828dSTrond Myklebust } 319961a828dSTrond Myklebust 320961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 321961a828dSTrond Myklebust { 322961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 323961a828dSTrond Myklebust return; 324961a828dSTrond Myklebust if (RPCXPRT_CONGESTED(xprt)) 325961a828dSTrond Myklebust goto out_unlock; 326961a828dSTrond Myklebust if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt)) 327961a828dSTrond Myklebust return; 3281da177e4SLinus Torvalds out_unlock: 329632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3301da177e4SLinus Torvalds } 3311da177e4SLinus Torvalds 3320695314eSTrond Myklebust static void xprt_task_clear_bytes_sent(struct rpc_task *task) 3330695314eSTrond Myklebust { 3340695314eSTrond Myklebust if (task != NULL) { 3350695314eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 3360695314eSTrond Myklebust if (req != NULL) 3370695314eSTrond Myklebust req->rq_bytes_sent = 0; 3380695314eSTrond Myklebust } 3390695314eSTrond Myklebust } 3400695314eSTrond Myklebust 34149e9a890SChuck Lever /** 34249e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 34349e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 34449e9a890SChuck Lever * @task: task that is releasing access to the transport 34549e9a890SChuck Lever * 34649e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 3471da177e4SLinus Torvalds */ 34849e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3491da177e4SLinus Torvalds { 3501da177e4SLinus Torvalds if (xprt->snd_task == task) { 3510695314eSTrond Myklebust xprt_task_clear_bytes_sent(task); 352632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3531da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3541da177e4SLinus Torvalds } 3551da177e4SLinus Torvalds } 35612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3571da177e4SLinus Torvalds 35849e9a890SChuck Lever /** 35949e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 36049e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 36149e9a890SChuck Lever * @task: task that is releasing access to the transport 36249e9a890SChuck Lever * 36349e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 36449e9a890SChuck Lever * transport if the transport's congestion window allows it. 36549e9a890SChuck Lever */ 36649e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 36749e9a890SChuck Lever { 36849e9a890SChuck Lever if (xprt->snd_task == task) { 3690695314eSTrond Myklebust xprt_task_clear_bytes_sent(task); 370632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 37149e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 37249e9a890SChuck Lever } 37349e9a890SChuck Lever } 37412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 37549e9a890SChuck Lever 37649e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3771da177e4SLinus Torvalds { 3784a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 37949e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3804a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3811da177e4SLinus Torvalds } 3821da177e4SLinus Torvalds 3831da177e4SLinus Torvalds /* 3841da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3851da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3861da177e4SLinus Torvalds */ 3871da177e4SLinus Torvalds static int 3881da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 3891da177e4SLinus Torvalds { 3901da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3911da177e4SLinus Torvalds 3921da177e4SLinus Torvalds if (req->rq_cong) 3931da177e4SLinus Torvalds return 1; 39446121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 3951da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 3961da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 3971da177e4SLinus Torvalds return 0; 3981da177e4SLinus Torvalds req->rq_cong = 1; 3991da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 4001da177e4SLinus Torvalds return 1; 4011da177e4SLinus Torvalds } 4021da177e4SLinus Torvalds 4031da177e4SLinus Torvalds /* 4041da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4051da177e4SLinus Torvalds * that has been sleeping due to congestion 4061da177e4SLinus Torvalds */ 4071da177e4SLinus Torvalds static void 4081da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4091da177e4SLinus Torvalds { 4101da177e4SLinus Torvalds if (!req->rq_cong) 4111da177e4SLinus Torvalds return; 4121da177e4SLinus Torvalds req->rq_cong = 0; 4131da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 41449e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4151da177e4SLinus Torvalds } 4161da177e4SLinus Torvalds 41746c0ee8bSChuck Lever /** 418a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 419a58dd398SChuck Lever * @task: RPC request that recently completed 420a58dd398SChuck Lever * 421a58dd398SChuck Lever * Useful for transports that require congestion control. 422a58dd398SChuck Lever */ 423a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 424a58dd398SChuck Lever { 425a4f0835cSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 426a4f0835cSTrond Myklebust 427a4f0835cSTrond Myklebust __xprt_put_cong(req->rq_xprt, req); 428a58dd398SChuck Lever } 42912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 430a58dd398SChuck Lever 431a58dd398SChuck Lever /** 43246c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 4336a24dfb6STrond Myklebust * @xprt: pointer to xprt 43446c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 43546c0ee8bSChuck Lever * @result: result code of completed RPC request 43646c0ee8bSChuck Lever * 4374f4cf5adSChuck Lever * The transport code maintains an estimate on the maximum number of out- 4384f4cf5adSChuck Lever * standing RPC requests, using a smoothed version of the congestion 4394f4cf5adSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 4404f4cf5adSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 4414f4cf5adSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 4424f4cf5adSChuck Lever * 4434f4cf5adSChuck Lever * - a reply is received and 4444f4cf5adSChuck Lever * - a full number of requests are outstanding and 4454f4cf5adSChuck Lever * - the congestion window hasn't been updated recently. 4461da177e4SLinus Torvalds */ 4476a24dfb6STrond Myklebust void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) 4481da177e4SLinus Torvalds { 44946c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 45046c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4511da177e4SLinus Torvalds 4521da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4531da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4541da177e4SLinus Torvalds * the result gets rounded properly. */ 4551da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4561da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4571da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 45849e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4591da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4601da177e4SLinus Torvalds cwnd >>= 1; 4611da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4621da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4631da177e4SLinus Torvalds } 4641da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4651da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4661da177e4SLinus Torvalds xprt->cwnd = cwnd; 46746c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4681da177e4SLinus Torvalds } 46912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4701da177e4SLinus Torvalds 47144fbac22SChuck Lever /** 47244fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 47344fbac22SChuck Lever * @xprt: transport with waiting tasks 47444fbac22SChuck Lever * @status: result code to plant in each task before waking it 47544fbac22SChuck Lever * 47644fbac22SChuck Lever */ 47744fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 47844fbac22SChuck Lever { 47944fbac22SChuck Lever if (status < 0) 48044fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 48144fbac22SChuck Lever else 48244fbac22SChuck Lever rpc_wake_up(&xprt->pending); 48344fbac22SChuck Lever } 48412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 48544fbac22SChuck Lever 486c7b2cae8SChuck Lever /** 487c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 488c7b2cae8SChuck Lever * @task: task to be put to sleep 4890b80ae42SRandy Dunlap * @action: function pointer to be executed after wait 490a9a6b52eSTrond Myklebust * 491a9a6b52eSTrond Myklebust * Note that we only set the timer for the case of RPC_IS_SOFT(), since 492a9a6b52eSTrond Myklebust * we don't in general want to force a socket disconnection due to 493a9a6b52eSTrond Myklebust * an incomplete RPC call transmission. 494c7b2cae8SChuck Lever */ 495b6ddf64fSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) 496c7b2cae8SChuck Lever { 497c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 498c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 499c7b2cae8SChuck Lever 500a9a6b52eSTrond Myklebust task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; 501b6ddf64fSTrond Myklebust rpc_sleep_on(&xprt->pending, task, action); 502c7b2cae8SChuck Lever } 50312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 504c7b2cae8SChuck Lever 505c7b2cae8SChuck Lever /** 506c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 507c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 508c7b2cae8SChuck Lever * 509c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 510c7b2cae8SChuck Lever */ 511c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 512c7b2cae8SChuck Lever { 513c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 514c7b2cae8SChuck Lever if (xprt->snd_task) { 51546121cf7SChuck Lever dprintk("RPC: write space: waking waiting task on " 51646121cf7SChuck Lever "xprt %p\n", xprt); 517fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); 518c7b2cae8SChuck Lever } 519c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 520c7b2cae8SChuck Lever } 52112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 522c7b2cae8SChuck Lever 523fe3aca29SChuck Lever /** 524fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 525fe3aca29SChuck Lever * @task: task whose timeout is to be set 526fe3aca29SChuck Lever * 527fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 528fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 529fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 530fe3aca29SChuck Lever */ 531fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 532fe3aca29SChuck Lever { 533fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 534fe3aca29SChuck Lever } 53512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 536fe3aca29SChuck Lever 5372c53040fSBen Hutchings /** 538fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout 539fe3aca29SChuck Lever * @task: task whose timeout is to be set 540fe3aca29SChuck Lever * 541fe3aca29SChuck Lever * Set a request's retransmit timeout using the RTT estimator. 542fe3aca29SChuck Lever */ 543fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 544fe3aca29SChuck Lever { 545fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 546ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 547ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 548fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 549ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 550fe3aca29SChuck Lever 551fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 552fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 553fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 554fe3aca29SChuck Lever task->tk_timeout = max_timeout; 555fe3aca29SChuck Lever } 55612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 557fe3aca29SChuck Lever 5581da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5591da177e4SLinus Torvalds { 560ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5611da177e4SLinus Torvalds 5621da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5631da177e4SLinus Torvalds if (to->to_exponential) 5641da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5651da177e4SLinus Torvalds else 5661da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 5671da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 5681da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 5691da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 5701da177e4SLinus Torvalds } 5711da177e4SLinus Torvalds 5729903cd1cSChuck Lever /** 5739903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 5749903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 5759903cd1cSChuck Lever * 5761da177e4SLinus Torvalds */ 5771da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 5781da177e4SLinus Torvalds { 5791da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 580ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5811da177e4SLinus Torvalds int status = 0; 5821da177e4SLinus Torvalds 5831da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 5841da177e4SLinus Torvalds if (to->to_exponential) 5851da177e4SLinus Torvalds req->rq_timeout <<= 1; 5861da177e4SLinus Torvalds else 5871da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 5881da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 5891da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 5901da177e4SLinus Torvalds req->rq_retries++; 5911da177e4SLinus Torvalds } else { 5921da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 5931da177e4SLinus Torvalds req->rq_retries = 0; 5941da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5951da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 5964a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5971da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 5984a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5991da177e4SLinus Torvalds status = -ETIMEDOUT; 6001da177e4SLinus Torvalds } 6011da177e4SLinus Torvalds 6021da177e4SLinus Torvalds if (req->rq_timeout == 0) { 6031da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 6041da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 6051da177e4SLinus Torvalds } 6061da177e4SLinus Torvalds return status; 6071da177e4SLinus Torvalds } 6081da177e4SLinus Torvalds 60965f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 6101da177e4SLinus Torvalds { 61165f27f38SDavid Howells struct rpc_xprt *xprt = 61265f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 6131da177e4SLinus Torvalds 61466af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 6154876cc77STrond Myklebust xprt->ops->close(xprt); 6161da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 61779234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 6181da177e4SLinus Torvalds } 6191da177e4SLinus Torvalds 6209903cd1cSChuck Lever /** 62162da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6229903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6239903cd1cSChuck Lever * 6241da177e4SLinus Torvalds */ 62562da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6261da177e4SLinus Torvalds { 6271da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6284a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6291da177e4SLinus Torvalds xprt_clear_connected(xprt); 6302a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6314a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6321da177e4SLinus Torvalds } 63362da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6341da177e4SLinus Torvalds 63566af1e55STrond Myklebust /** 63666af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 63766af1e55STrond Myklebust * @xprt: transport to disconnect 63866af1e55STrond Myklebust * 63966af1e55STrond Myklebust */ 64066af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 64166af1e55STrond Myklebust { 64266af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 64366af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 64466af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 64566af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 64666af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 64766af1e55STrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6482a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 64966af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 65066af1e55STrond Myklebust } 65166af1e55STrond Myklebust 6527c1d71cfSTrond Myklebust /** 6537c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 6547c1d71cfSTrond Myklebust * @xprt: transport to disconnect 6557c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 6567c1d71cfSTrond Myklebust * 6577c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 6587c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 6597c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 6607c1d71cfSTrond Myklebust * a batch of RPC requests. 6617c1d71cfSTrond Myklebust * 6627c1d71cfSTrond Myklebust */ 6637c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 6647c1d71cfSTrond Myklebust { 6657c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 6667c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 6677c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 6687c1d71cfSTrond Myklebust goto out; 6697c1d71cfSTrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) 6707c1d71cfSTrond Myklebust goto out; 6717c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 6727c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 6737c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 6747c1d71cfSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6752a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6767c1d71cfSTrond Myklebust out: 6777c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 6787c1d71cfSTrond Myklebust } 6797c1d71cfSTrond Myklebust 6801da177e4SLinus Torvalds static void 6811da177e4SLinus Torvalds xprt_init_autodisconnect(unsigned long data) 6821da177e4SLinus Torvalds { 6831da177e4SLinus Torvalds struct rpc_xprt *xprt = (struct rpc_xprt *)data; 6841da177e4SLinus Torvalds 6854a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 686d19751e7STrond Myklebust if (!list_empty(&xprt->recv)) 6871da177e4SLinus Torvalds goto out_abort; 6882226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 6891da177e4SLinus Torvalds goto out_abort; 6904a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 691c1384c9cSTrond Myklebust queue_work(rpciod_workqueue, &xprt->task_cleanup); 6921da177e4SLinus Torvalds return; 6931da177e4SLinus Torvalds out_abort: 6944a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 6951da177e4SLinus Torvalds } 6961da177e4SLinus Torvalds 697718ba5b8STrond Myklebust bool xprt_lock_connect(struct rpc_xprt *xprt, 698718ba5b8STrond Myklebust struct rpc_task *task, 699718ba5b8STrond Myklebust void *cookie) 700718ba5b8STrond Myklebust { 701718ba5b8STrond Myklebust bool ret = false; 702718ba5b8STrond Myklebust 703718ba5b8STrond Myklebust spin_lock_bh(&xprt->transport_lock); 704718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 705718ba5b8STrond Myklebust goto out; 706718ba5b8STrond Myklebust if (xprt->snd_task != task) 707718ba5b8STrond Myklebust goto out; 7080695314eSTrond Myklebust xprt_task_clear_bytes_sent(task); 709718ba5b8STrond Myklebust xprt->snd_task = cookie; 710718ba5b8STrond Myklebust ret = true; 711718ba5b8STrond Myklebust out: 712718ba5b8STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 713718ba5b8STrond Myklebust return ret; 714718ba5b8STrond Myklebust } 715718ba5b8STrond Myklebust 716718ba5b8STrond Myklebust void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) 717718ba5b8STrond Myklebust { 718718ba5b8STrond Myklebust spin_lock_bh(&xprt->transport_lock); 719718ba5b8STrond Myklebust if (xprt->snd_task != cookie) 720718ba5b8STrond Myklebust goto out; 721718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 722718ba5b8STrond Myklebust goto out; 723718ba5b8STrond Myklebust xprt->snd_task =NULL; 724718ba5b8STrond Myklebust xprt->ops->release_xprt(xprt, NULL); 725718ba5b8STrond Myklebust out: 726718ba5b8STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 72779234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 728718ba5b8STrond Myklebust } 729718ba5b8STrond Myklebust 7309903cd1cSChuck Lever /** 7319903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 7329903cd1cSChuck Lever * @task: RPC task that is requesting the connect 7331da177e4SLinus Torvalds * 7341da177e4SLinus Torvalds */ 7351da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 7361da177e4SLinus Torvalds { 737ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 7381da177e4SLinus Torvalds 73946121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 7401da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 7411da177e4SLinus Torvalds 742ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 74301d37c42STrond Myklebust task->tk_status = -EAGAIN; 7441da177e4SLinus Torvalds return; 7451da177e4SLinus Torvalds } 7461da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 7471da177e4SLinus Torvalds return; 748feb8ca37STrond Myklebust 749feb8ca37STrond Myklebust if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) 750feb8ca37STrond Myklebust xprt->ops->close(xprt); 751feb8ca37STrond Myklebust 752718ba5b8STrond Myklebust if (!xprt_connected(xprt)) { 7531da177e4SLinus Torvalds task->tk_rqstp->rq_bytes_sent = 0; 754a8ce4a8fSTrond Myklebust task->tk_timeout = task->tk_rqstp->rq_timeout; 7555d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_connect_status); 7560b9e7943STrond Myklebust 7570b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 7580b9e7943STrond Myklebust return; 7590b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 7600b9e7943STrond Myklebust return; 761262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 7621b092092STrond Myklebust xprt->ops->connect(xprt, task); 7631da177e4SLinus Torvalds } 764718ba5b8STrond Myklebust xprt_release_write(xprt, task); 7651da177e4SLinus Torvalds } 7661da177e4SLinus Torvalds 7679903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 7681da177e4SLinus Torvalds { 769ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 7701da177e4SLinus Torvalds 771cd983ef8SChuck Lever if (task->tk_status == 0) { 772262ca07dSChuck Lever xprt->stat.connect_count++; 773262ca07dSChuck Lever xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; 77446121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connection established\n", 7751da177e4SLinus Torvalds task->tk_pid); 7761da177e4SLinus Torvalds return; 7771da177e4SLinus Torvalds } 7781da177e4SLinus Torvalds 7791da177e4SLinus Torvalds switch (task->tk_status) { 7800fe8d04eSTrond Myklebust case -ECONNREFUSED: 7810fe8d04eSTrond Myklebust case -ECONNRESET: 7820fe8d04eSTrond Myklebust case -ECONNABORTED: 7830fe8d04eSTrond Myklebust case -ENETUNREACH: 7840fe8d04eSTrond Myklebust case -EHOSTUNREACH: 7852fc193cfSTrond Myklebust case -EPIPE: 7862a491991STrond Myklebust case -EAGAIN: 7872a491991STrond Myklebust dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); 78823475d66SChuck Lever break; 7891da177e4SLinus Torvalds case -ETIMEDOUT: 79046121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connect attempt timed " 79146121cf7SChuck Lever "out\n", task->tk_pid); 7921da177e4SLinus Torvalds break; 7931da177e4SLinus Torvalds default: 79446121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: error %d connecting to " 79546121cf7SChuck Lever "server %s\n", task->tk_pid, -task->tk_status, 7964e0038b6STrond Myklebust xprt->servername); 79723475d66SChuck Lever task->tk_status = -EIO; 79823475d66SChuck Lever } 7991da177e4SLinus Torvalds } 8001da177e4SLinus Torvalds 8019903cd1cSChuck Lever /** 8029903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 8039903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 8049903cd1cSChuck Lever * @xid: RPC XID of incoming reply 8059903cd1cSChuck Lever * 8061da177e4SLinus Torvalds */ 807d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 8081da177e4SLinus Torvalds { 8098f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 8101da177e4SLinus Torvalds 8118f3a6de3SPavel Emelyanov list_for_each_entry(entry, &xprt->recv, rq_list) 8123705ad64SJeff Layton if (entry->rq_xid == xid) { 8133705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, 0); 814262ca07dSChuck Lever return entry; 8153705ad64SJeff Layton } 81646121cf7SChuck Lever 81746121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 81846121cf7SChuck Lever ntohl(xid)); 8193705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, -ENOENT); 820262ca07dSChuck Lever xprt->stat.bad_xids++; 821262ca07dSChuck Lever return NULL; 8221da177e4SLinus Torvalds } 82312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 8241da177e4SLinus Torvalds 825bbc72ceaSChuck Lever static void xprt_update_rtt(struct rpc_task *task) 8261da177e4SLinus Torvalds { 8271570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 8281570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 82995c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 830d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 8311570c1e4SChuck Lever 8321da177e4SLinus Torvalds if (timer) { 8331da177e4SLinus Torvalds if (req->rq_ntrans == 1) 834ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 8351570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 8361da177e4SLinus Torvalds } 8371da177e4SLinus Torvalds } 8381da177e4SLinus Torvalds 8391570c1e4SChuck Lever /** 8401570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 8411570c1e4SChuck Lever * @task: RPC request that recently completed 8421570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 8431570c1e4SChuck Lever * 8441570c1e4SChuck Lever * Caller holds transport lock. 8451570c1e4SChuck Lever */ 8461570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 8471570c1e4SChuck Lever { 8481570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 849fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 8501da177e4SLinus Torvalds 8511570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 8521570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 8533705ad64SJeff Layton trace_xprt_complete_rqst(xprt, req->rq_xid, copied); 8541da177e4SLinus Torvalds 855fda13939STrond Myklebust xprt->stat.recvs++; 856d60dbb20STrond Myklebust req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); 857bbc72ceaSChuck Lever if (xprt->ops->timer != NULL) 858bbc72ceaSChuck Lever xprt_update_rtt(task); 859ef759a2eSChuck Lever 8601da177e4SLinus Torvalds list_del_init(&req->rq_list); 8611e799b67STrond Myklebust req->rq_private_buf.len = copied; 862dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 863dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 86443ac3f29STrond Myklebust smp_wmb(); 865dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 866fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 8671da177e4SLinus Torvalds } 86812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 8691da177e4SLinus Torvalds 87046c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 8711da177e4SLinus Torvalds { 8721da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 8731da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 8741da177e4SLinus Torvalds 8755d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 8765d00837bSTrond Myklebust return; 87746121cf7SChuck Lever dprintk("RPC: %5u xprt_timer\n", task->tk_pid); 87846c0ee8bSChuck Lever 8795d00837bSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 880dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 88146c0ee8bSChuck Lever if (xprt->ops->timer) 8826a24dfb6STrond Myklebust xprt->ops->timer(xprt, task); 8835d00837bSTrond Myklebust } else 8845d00837bSTrond Myklebust task->tk_status = 0; 8855d00837bSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 8861da177e4SLinus Torvalds } 8871da177e4SLinus Torvalds 8884cfc7e60SRahul Iyer static inline int xprt_has_timer(struct rpc_xprt *xprt) 8894cfc7e60SRahul Iyer { 8904cfc7e60SRahul Iyer return xprt->idle_timeout != 0; 8914cfc7e60SRahul Iyer } 8924cfc7e60SRahul Iyer 8939903cd1cSChuck Lever /** 8949903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 8959903cd1cSChuck Lever * @task: RPC task about to send a request 8969903cd1cSChuck Lever * 8971da177e4SLinus Torvalds */ 89890051ea7STrond Myklebust bool xprt_prepare_transmit(struct rpc_task *task) 8991da177e4SLinus Torvalds { 9001da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 9011da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 90290051ea7STrond Myklebust bool ret = false; 9031da177e4SLinus Torvalds 90446121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 9051da177e4SLinus Torvalds 9064a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 9078a19a0b6STrond Myklebust if (!req->rq_bytes_sent) { 9088a19a0b6STrond Myklebust if (req->rq_reply_bytes_recvd) { 90990051ea7STrond Myklebust task->tk_status = req->rq_reply_bytes_recvd; 9101da177e4SLinus Torvalds goto out_unlock; 9111da177e4SLinus Torvalds } 9128a19a0b6STrond Myklebust if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) 9138a19a0b6STrond Myklebust && xprt_connected(xprt) 9148a19a0b6STrond Myklebust && req->rq_connect_cookie == xprt->connect_cookie) { 9158a19a0b6STrond Myklebust xprt->ops->set_retrans_timeout(task); 9168a19a0b6STrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 9178a19a0b6STrond Myklebust goto out_unlock; 9188a19a0b6STrond Myklebust } 9198a19a0b6STrond Myklebust } 92090051ea7STrond Myklebust if (!xprt->ops->reserve_xprt(xprt, task)) { 92190051ea7STrond Myklebust task->tk_status = -EAGAIN; 92290051ea7STrond Myklebust goto out_unlock; 92390051ea7STrond Myklebust } 92490051ea7STrond Myklebust ret = true; 9251da177e4SLinus Torvalds out_unlock: 9264a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 92790051ea7STrond Myklebust return ret; 9281da177e4SLinus Torvalds } 9291da177e4SLinus Torvalds 930e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 9315e5ce5beSTrond Myklebust { 932343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 9335e5ce5beSTrond Myklebust } 9345e5ce5beSTrond Myklebust 9359903cd1cSChuck Lever /** 9369903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 9379903cd1cSChuck Lever * @task: controlling RPC task 9389903cd1cSChuck Lever * 9399903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 9409903cd1cSChuck Lever */ 9419903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 9421da177e4SLinus Torvalds { 9431da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 9441da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 94515a45206SAndy Adamson int status, numreqs; 9461da177e4SLinus Torvalds 94746121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 9481da177e4SLinus Torvalds 949dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 95055ae1aabSRicardo Labiaga if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { 95155ae1aabSRicardo Labiaga /* 95255ae1aabSRicardo Labiaga * Add to the list only if we're expecting a reply 95355ae1aabSRicardo Labiaga */ 9544a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 9551da177e4SLinus Torvalds /* Update the softirq receive buffer */ 9561da177e4SLinus Torvalds memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 9571da177e4SLinus Torvalds sizeof(req->rq_private_buf)); 9581da177e4SLinus Torvalds /* Add request to the receive list */ 9591da177e4SLinus Torvalds list_add_tail(&req->rq_list, &xprt->recv); 9604a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 9611da177e4SLinus Torvalds xprt_reset_majortimeo(req); 9620f9dc2b1STrond Myklebust /* Turn off autodisconnect */ 9630f9dc2b1STrond Myklebust del_singleshot_timer_sync(&xprt->timer); 9641da177e4SLinus Torvalds } 9651da177e4SLinus Torvalds } else if (!req->rq_bytes_sent) 9661da177e4SLinus Torvalds return; 9671da177e4SLinus Torvalds 968ff839970SChuck Lever req->rq_xtime = ktime_get(); 969a246b010SChuck Lever status = xprt->ops->send_request(task); 9703705ad64SJeff Layton trace_xprt_transmit(xprt, req->rq_xid, status); 971c8485e4dSTrond Myklebust if (status != 0) { 972c8485e4dSTrond Myklebust task->tk_status = status; 973c8485e4dSTrond Myklebust return; 974c8485e4dSTrond Myklebust } 9754a068258SChuck Lever xprt_inject_disconnect(xprt); 976c8485e4dSTrond Myklebust 97746121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 978468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 979fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 980262ca07dSChuck Lever 981fe3aca29SChuck Lever xprt->ops->set_retrans_timeout(task); 982262ca07dSChuck Lever 98315a45206SAndy Adamson numreqs = atomic_read(&xprt->num_reqs); 98415a45206SAndy Adamson if (numreqs > xprt->stat.max_slots) 98515a45206SAndy Adamson xprt->stat.max_slots = numreqs; 986262ca07dSChuck Lever xprt->stat.sends++; 987262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 988262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 98915a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 99015a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 991262ca07dSChuck Lever 992fe3aca29SChuck Lever /* Don't race with disconnect */ 993fe3aca29SChuck Lever if (!xprt_connected(xprt)) 994fe3aca29SChuck Lever task->tk_status = -ENOTCONN; 9950a660521STrond Myklebust else { 99655ae1aabSRicardo Labiaga /* 99755ae1aabSRicardo Labiaga * Sleep on the pending queue since 99855ae1aabSRicardo Labiaga * we're expecting a reply. 99955ae1aabSRicardo Labiaga */ 10000a660521STrond Myklebust if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) 10015d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 10020a660521STrond Myklebust req->rq_connect_cookie = xprt->connect_cookie; 100355ae1aabSRicardo Labiaga } 1004fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 10051da177e4SLinus Torvalds } 10061da177e4SLinus Torvalds 1007ba60eb25STrond Myklebust static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) 1008ba60eb25STrond Myklebust { 1009ba60eb25STrond Myklebust set_bit(XPRT_CONGESTED, &xprt->state); 1010ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1011ba60eb25STrond Myklebust } 1012ba60eb25STrond Myklebust 1013ba60eb25STrond Myklebust static void xprt_wake_up_backlog(struct rpc_xprt *xprt) 1014ba60eb25STrond Myklebust { 1015ba60eb25STrond Myklebust if (rpc_wake_up_next(&xprt->backlog) == NULL) 1016ba60eb25STrond Myklebust clear_bit(XPRT_CONGESTED, &xprt->state); 1017ba60eb25STrond Myklebust } 1018ba60eb25STrond Myklebust 1019ba60eb25STrond Myklebust static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) 1020ba60eb25STrond Myklebust { 1021ba60eb25STrond Myklebust bool ret = false; 1022ba60eb25STrond Myklebust 1023ba60eb25STrond Myklebust if (!test_bit(XPRT_CONGESTED, &xprt->state)) 1024ba60eb25STrond Myklebust goto out; 1025ba60eb25STrond Myklebust spin_lock(&xprt->reserve_lock); 1026ba60eb25STrond Myklebust if (test_bit(XPRT_CONGESTED, &xprt->state)) { 1027ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1028ba60eb25STrond Myklebust ret = true; 1029ba60eb25STrond Myklebust } 1030ba60eb25STrond Myklebust spin_unlock(&xprt->reserve_lock); 1031ba60eb25STrond Myklebust out: 1032ba60eb25STrond Myklebust return ret; 1033ba60eb25STrond Myklebust } 1034ba60eb25STrond Myklebust 1035d9ba131dSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) 1036d9ba131dSTrond Myklebust { 1037d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 1038d9ba131dSTrond Myklebust 1039d9ba131dSTrond Myklebust if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) 1040d9ba131dSTrond Myklebust goto out; 1041d9ba131dSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); 1042d9ba131dSTrond Myklebust if (req != NULL) 1043d9ba131dSTrond Myklebust goto out; 1044d9ba131dSTrond Myklebust atomic_dec(&xprt->num_reqs); 1045d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 1046d9ba131dSTrond Myklebust out: 1047d9ba131dSTrond Myklebust return req; 1048d9ba131dSTrond Myklebust } 1049d9ba131dSTrond Myklebust 1050d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1051d9ba131dSTrond Myklebust { 1052d9ba131dSTrond Myklebust if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { 1053d9ba131dSTrond Myklebust kfree(req); 1054d9ba131dSTrond Myklebust return true; 1055d9ba131dSTrond Myklebust } 1056d9ba131dSTrond Myklebust return false; 1057d9ba131dSTrond Myklebust } 1058d9ba131dSTrond Myklebust 1059f39c1bfbSTrond Myklebust void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 10601da177e4SLinus Torvalds { 1061d9ba131dSTrond Myklebust struct rpc_rqst *req; 10621da177e4SLinus Torvalds 1063f39c1bfbSTrond Myklebust spin_lock(&xprt->reserve_lock); 10641da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 1065d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 1066d9ba131dSTrond Myklebust list_del(&req->rq_list); 1067d9ba131dSTrond Myklebust goto out_init_req; 1068d9ba131dSTrond Myklebust } 10696b343099SJeff Layton req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN); 1070d9ba131dSTrond Myklebust if (!IS_ERR(req)) 1071d9ba131dSTrond Myklebust goto out_init_req; 1072d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 1073d9ba131dSTrond Myklebust case -ENOMEM: 1074d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 1075d9ba131dSTrond Myklebust "failed! Retrying\n"); 10761afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 1077d9ba131dSTrond Myklebust break; 1078d9ba131dSTrond Myklebust case -EAGAIN: 1079ba60eb25STrond Myklebust xprt_add_backlog(xprt, task); 1080d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 10811afeaf5cSTrond Myklebust default: 1082d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 10831afeaf5cSTrond Myklebust } 1084f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 1085d9ba131dSTrond Myklebust return; 1086d9ba131dSTrond Myklebust out_init_req: 1087d9ba131dSTrond Myklebust task->tk_status = 0; 10881da177e4SLinus Torvalds task->tk_rqstp = req; 10891da177e4SLinus Torvalds xprt_request_init(task, xprt); 1090f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 10911da177e4SLinus Torvalds } 1092f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_alloc_slot); 1093f39c1bfbSTrond Myklebust 1094f39c1bfbSTrond Myklebust void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 1095f39c1bfbSTrond Myklebust { 1096f39c1bfbSTrond Myklebust /* Note: grabbing the xprt_lock_write() ensures that we throttle 1097f39c1bfbSTrond Myklebust * new slot allocation if the transport is congested (i.e. when 1098f39c1bfbSTrond Myklebust * reconnecting a stream transport or when out of socket write 1099f39c1bfbSTrond Myklebust * buffer space). 1100f39c1bfbSTrond Myklebust */ 1101f39c1bfbSTrond Myklebust if (xprt_lock_write(xprt, task)) { 1102f39c1bfbSTrond Myklebust xprt_alloc_slot(xprt, task); 1103f39c1bfbSTrond Myklebust xprt_release_write(xprt, task); 1104f39c1bfbSTrond Myklebust } 1105f39c1bfbSTrond Myklebust } 1106f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot); 11071da177e4SLinus Torvalds 1108ee5ebe85STrond Myklebust static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1109ee5ebe85STrond Myklebust { 1110ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1111c25573b5STrond Myklebust if (!xprt_dynamic_free_slot(xprt, req)) { 1112c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1113ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1114c25573b5STrond Myklebust } 1115ba60eb25STrond Myklebust xprt_wake_up_backlog(xprt); 1116ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1117ee5ebe85STrond Myklebust } 1118ee5ebe85STrond Myklebust 111921de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 112021de0a95STrond Myklebust { 112121de0a95STrond Myklebust struct rpc_rqst *req; 112221de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 112321de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 112421de0a95STrond Myklebust list_del(&req->rq_list); 112521de0a95STrond Myklebust kfree(req); 112621de0a95STrond Myklebust } 112721de0a95STrond Myklebust } 112821de0a95STrond Myklebust 1129d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1130d9ba131dSTrond Myklebust unsigned int num_prealloc, 1131d9ba131dSTrond Myklebust unsigned int max_alloc) 1132bd1722d4SPavel Emelyanov { 1133bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 113421de0a95STrond Myklebust struct rpc_rqst *req; 113521de0a95STrond Myklebust int i; 1136bd1722d4SPavel Emelyanov 1137bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1138bd1722d4SPavel Emelyanov if (xprt == NULL) 1139bd1722d4SPavel Emelyanov goto out; 1140bd1722d4SPavel Emelyanov 114121de0a95STrond Myklebust xprt_init(xprt, net); 114221de0a95STrond Myklebust 114321de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 114421de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 114521de0a95STrond Myklebust if (!req) 11468313164cSwangweidong goto out_free; 114721de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 114821de0a95STrond Myklebust } 1149d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1150d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1151d9ba131dSTrond Myklebust else 115221de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1153d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1154d9ba131dSTrond Myklebust atomic_set(&xprt->num_reqs, num_prealloc); 1155bd1722d4SPavel Emelyanov 1156bd1722d4SPavel Emelyanov return xprt; 1157bd1722d4SPavel Emelyanov 1158bd1722d4SPavel Emelyanov out_free: 115921de0a95STrond Myklebust xprt_free(xprt); 1160bd1722d4SPavel Emelyanov out: 1161bd1722d4SPavel Emelyanov return NULL; 1162bd1722d4SPavel Emelyanov } 1163bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1164bd1722d4SPavel Emelyanov 1165e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1166e204e621SPavel Emelyanov { 116737aa2133SPavel Emelyanov put_net(xprt->xprt_net); 116821de0a95STrond Myklebust xprt_free_all_slots(xprt); 1169e204e621SPavel Emelyanov kfree(xprt); 1170e204e621SPavel Emelyanov } 1171e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1172e204e621SPavel Emelyanov 11739903cd1cSChuck Lever /** 11749903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 11759903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 11769903cd1cSChuck Lever * 1177ba60eb25STrond Myklebust * If the transport is marked as being congested, or if no more 1178ba60eb25STrond Myklebust * slots are available, place the task on the transport's 11799903cd1cSChuck Lever * backlog queue. 11809903cd1cSChuck Lever */ 11819903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 11821da177e4SLinus Torvalds { 118345bc0dceSTrond Myklebust struct rpc_xprt *xprt; 11841da177e4SLinus Torvalds 118543cedbf0STrond Myklebust task->tk_status = 0; 118643cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 118743cedbf0STrond Myklebust return; 118843cedbf0STrond Myklebust 118943cedbf0STrond Myklebust task->tk_timeout = 0; 119043cedbf0STrond Myklebust task->tk_status = -EAGAIN; 119145bc0dceSTrond Myklebust rcu_read_lock(); 119245bc0dceSTrond Myklebust xprt = rcu_dereference(task->tk_client->cl_xprt); 1193ba60eb25STrond Myklebust if (!xprt_throttle_congested(xprt, task)) 1194ba60eb25STrond Myklebust xprt->ops->alloc_slot(xprt, task); 1195ba60eb25STrond Myklebust rcu_read_unlock(); 1196ba60eb25STrond Myklebust } 1197ba60eb25STrond Myklebust 1198ba60eb25STrond Myklebust /** 1199ba60eb25STrond Myklebust * xprt_retry_reserve - allocate an RPC request slot 1200ba60eb25STrond Myklebust * @task: RPC task requesting a slot allocation 1201ba60eb25STrond Myklebust * 1202ba60eb25STrond Myklebust * If no more slots are available, place the task on the transport's 1203ba60eb25STrond Myklebust * backlog queue. 1204ba60eb25STrond Myklebust * Note that the only difference with xprt_reserve is that we now 1205ba60eb25STrond Myklebust * ignore the value of the XPRT_CONGESTED flag. 1206ba60eb25STrond Myklebust */ 1207ba60eb25STrond Myklebust void xprt_retry_reserve(struct rpc_task *task) 1208ba60eb25STrond Myklebust { 1209ba60eb25STrond Myklebust struct rpc_xprt *xprt; 1210ba60eb25STrond Myklebust 1211ba60eb25STrond Myklebust task->tk_status = 0; 1212ba60eb25STrond Myklebust if (task->tk_rqstp != NULL) 1213ba60eb25STrond Myklebust return; 1214ba60eb25STrond Myklebust 1215ba60eb25STrond Myklebust task->tk_timeout = 0; 1216ba60eb25STrond Myklebust task->tk_status = -EAGAIN; 1217ba60eb25STrond Myklebust rcu_read_lock(); 1218ba60eb25STrond Myklebust xprt = rcu_dereference(task->tk_client->cl_xprt); 1219f39c1bfbSTrond Myklebust xprt->ops->alloc_slot(xprt, task); 122045bc0dceSTrond Myklebust rcu_read_unlock(); 12211da177e4SLinus Torvalds } 12221da177e4SLinus Torvalds 1223d8ed029dSAlexey Dobriyan static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) 12241da177e4SLinus Torvalds { 12250eae88f3SEric Dumazet return (__force __be32)xprt->xid++; 12261da177e4SLinus Torvalds } 12271da177e4SLinus Torvalds 12281da177e4SLinus Torvalds static inline void xprt_init_xid(struct rpc_xprt *xprt) 12291da177e4SLinus Torvalds { 123063862b5bSAruna-Hewapathirane xprt->xid = prandom_u32(); 12311da177e4SLinus Torvalds } 12321da177e4SLinus Torvalds 12339903cd1cSChuck Lever static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) 12341da177e4SLinus Torvalds { 12351da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 12361da177e4SLinus Torvalds 1237d9ba131dSTrond Myklebust INIT_LIST_HEAD(&req->rq_list); 1238ba7392bbSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 12391da177e4SLinus Torvalds req->rq_task = task; 12401da177e4SLinus Torvalds req->rq_xprt = xprt; 124102107148SChuck Lever req->rq_buffer = NULL; 12421da177e4SLinus Torvalds req->rq_xid = xprt_alloc_xid(xprt); 12430a660521STrond Myklebust req->rq_connect_cookie = xprt->connect_cookie - 1; 124492551948STrond Myklebust req->rq_bytes_sent = 0; 124592551948STrond Myklebust req->rq_snd_buf.len = 0; 124692551948STrond Myklebust req->rq_snd_buf.buflen = 0; 124792551948STrond Myklebust req->rq_rcv_buf.len = 0; 124892551948STrond Myklebust req->rq_rcv_buf.buflen = 0; 1249ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf = NULL; 1250da45828eSTrond Myklebust xprt_reset_majortimeo(req); 125146121cf7SChuck Lever dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 12521da177e4SLinus Torvalds req, ntohl(req->rq_xid)); 12531da177e4SLinus Torvalds } 12541da177e4SLinus Torvalds 12559903cd1cSChuck Lever /** 12569903cd1cSChuck Lever * xprt_release - release an RPC request slot 12579903cd1cSChuck Lever * @task: task which is finished with the slot 12589903cd1cSChuck Lever * 12591da177e4SLinus Torvalds */ 12609903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 12611da177e4SLinus Torvalds { 126255ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 126387ed5003STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12641da177e4SLinus Torvalds 126587ed5003STrond Myklebust if (req == NULL) { 126687ed5003STrond Myklebust if (task->tk_client) { 126787ed5003STrond Myklebust rcu_read_lock(); 126887ed5003STrond Myklebust xprt = rcu_dereference(task->tk_client->cl_xprt); 126987ed5003STrond Myklebust if (xprt->snd_task == task) 127087ed5003STrond Myklebust xprt_release_write(xprt, task); 127187ed5003STrond Myklebust rcu_read_unlock(); 127287ed5003STrond Myklebust } 12731da177e4SLinus Torvalds return; 127487ed5003STrond Myklebust } 127555ae1aabSRicardo Labiaga 127655ae1aabSRicardo Labiaga xprt = req->rq_xprt; 12770a702195SWeston Andros Adamson if (task->tk_ops->rpc_count_stats != NULL) 12780a702195SWeston Andros Adamson task->tk_ops->rpc_count_stats(task, task->tk_calldata); 12790a702195SWeston Andros Adamson else if (task->tk_client) 12800a702195SWeston Andros Adamson rpc_count_iostats(task, task->tk_client->cl_metrics); 12814a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 128249e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1283a58dd398SChuck Lever if (xprt->ops->release_request) 1284a58dd398SChuck Lever xprt->ops->release_request(task); 12851da177e4SLinus Torvalds if (!list_empty(&req->rq_list)) 12861da177e4SLinus Torvalds list_del(&req->rq_list); 12871da177e4SLinus Torvalds xprt->last_used = jiffies; 12884cfc7e60SRahul Iyer if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) 1289a246b010SChuck Lever mod_timer(&xprt->timer, 129003bf4b70SChuck Lever xprt->last_used + xprt->idle_timeout); 12914a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1292ee5ebe85STrond Myklebust if (req->rq_buffer) 1293c5a4dd8bSChuck Lever xprt->ops->buf_free(req->rq_buffer); 12944a068258SChuck Lever xprt_inject_disconnect(xprt); 1295a17c2153STrond Myklebust if (req->rq_cred != NULL) 1296a17c2153STrond Myklebust put_rpccred(req->rq_cred); 12971da177e4SLinus Torvalds task->tk_rqstp = NULL; 1298ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1299ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 130055ae1aabSRicardo Labiaga 130146121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 1302ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1303ee5ebe85STrond Myklebust xprt_free_slot(xprt, req); 1304ee5ebe85STrond Myklebust else 1305c9acb42eSTrond Myklebust xprt_free_bc_request(req); 13061da177e4SLinus Torvalds } 13071da177e4SLinus Torvalds 130821de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1309c2866763SChuck Lever { 131021de0a95STrond Myklebust atomic_set(&xprt->count, 1); 1311c2866763SChuck Lever 1312c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1313c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 1314c2866763SChuck Lever 1315c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 1316c2866763SChuck Lever INIT_LIST_HEAD(&xprt->recv); 13179e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1318f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1319f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 13209e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1321f9acac1aSRicardo Labiaga 1322c2866763SChuck Lever xprt->last_used = jiffies; 1323c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1324a509050bSChuck Lever xprt->bind_index = 0; 1325c2866763SChuck Lever 1326c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1327c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 132834006ceeSTrond Myklebust rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); 1329c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1330c2866763SChuck Lever 1331c2866763SChuck Lever xprt_init_xid(xprt); 1332c2866763SChuck Lever 133321de0a95STrond Myklebust xprt->xprt_net = get_net(net); 13348d9266ffSTrond Myklebust } 13358d9266ffSTrond Myklebust 13368d9266ffSTrond Myklebust /** 13378d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 13388d9266ffSTrond Myklebust * @args: rpc transport creation arguments 13398d9266ffSTrond Myklebust * 13408d9266ffSTrond Myklebust */ 13418d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 13428d9266ffSTrond Myklebust { 13438d9266ffSTrond Myklebust struct rpc_xprt *xprt; 13448d9266ffSTrond Myklebust struct xprt_class *t; 13458d9266ffSTrond Myklebust 13468d9266ffSTrond Myklebust spin_lock(&xprt_list_lock); 13478d9266ffSTrond Myklebust list_for_each_entry(t, &xprt_list, list) { 13488d9266ffSTrond Myklebust if (t->ident == args->ident) { 13498d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 13508d9266ffSTrond Myklebust goto found; 13518d9266ffSTrond Myklebust } 13528d9266ffSTrond Myklebust } 13538d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 13543c45ddf8SChuck Lever dprintk("RPC: transport (%d) not supported\n", args->ident); 13558d9266ffSTrond Myklebust return ERR_PTR(-EIO); 13568d9266ffSTrond Myklebust 13578d9266ffSTrond Myklebust found: 13588d9266ffSTrond Myklebust xprt = t->setup(args); 13598d9266ffSTrond Myklebust if (IS_ERR(xprt)) { 13608d9266ffSTrond Myklebust dprintk("RPC: xprt_create_transport: failed, %ld\n", 13618d9266ffSTrond Myklebust -PTR_ERR(xprt)); 136221de0a95STrond Myklebust goto out; 13638d9266ffSTrond Myklebust } 136433d90ac0SJ. Bruce Fields if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) 136533d90ac0SJ. Bruce Fields xprt->idle_timeout = 0; 136621de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 136721de0a95STrond Myklebust if (xprt_has_timer(xprt)) 136821de0a95STrond Myklebust setup_timer(&xprt->timer, xprt_init_autodisconnect, 136921de0a95STrond Myklebust (unsigned long)xprt); 137021de0a95STrond Myklebust else 137121de0a95STrond Myklebust init_timer(&xprt->timer); 13724e0038b6STrond Myklebust 13734e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 13744e0038b6STrond Myklebust xprt_destroy(xprt); 13754e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 13764e0038b6STrond Myklebust } 13774e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 13784e0038b6STrond Myklebust if (xprt->servername == NULL) { 13794e0038b6STrond Myklebust xprt_destroy(xprt); 13804e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 13814e0038b6STrond Myklebust } 13824e0038b6STrond Myklebust 13833f940098SJeff Layton rpc_xprt_debugfs_register(xprt); 1384388f0c77SJeff Layton 1385c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1386c2866763SChuck Lever xprt->max_reqs); 138721de0a95STrond Myklebust out: 1388c2866763SChuck Lever return xprt; 1389c2866763SChuck Lever } 1390c2866763SChuck Lever 13919903cd1cSChuck Lever /** 13929903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 1393a8de240aSTrond Myklebust * @xprt: transport to destroy 13949903cd1cSChuck Lever * 13951da177e4SLinus Torvalds */ 1396a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 13971da177e4SLinus Torvalds { 13981da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 139979234c3dSTrond Myklebust 140079234c3dSTrond Myklebust /* Exclude transport connect/disconnect handlers */ 140179234c3dSTrond Myklebust wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); 140279234c3dSTrond Myklebust 14030065db32STrond Myklebust del_timer_sync(&xprt->timer); 1404c8541ecdSChuck Lever 1405388f0c77SJeff Layton rpc_xprt_debugfs_unregister(xprt); 1406f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1407f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1408f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1409f6a1cc89STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1410c3ae62aeSJ. Bruce Fields cancel_work_sync(&xprt->task_cleanup); 14114e0038b6STrond Myklebust kfree(xprt->servername); 1412c8541ecdSChuck Lever /* 1413c8541ecdSChuck Lever * Tear down transport state and free the rpc_xprt 1414c8541ecdSChuck Lever */ 1415a246b010SChuck Lever xprt->ops->destroy(xprt); 14166b6ca86bSTrond Myklebust } 14171da177e4SLinus Torvalds 14186b6ca86bSTrond Myklebust /** 14196b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 14206b6ca86bSTrond Myklebust * @xprt: pointer to the transport 14216b6ca86bSTrond Myklebust * 14226b6ca86bSTrond Myklebust */ 14236b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 14246b6ca86bSTrond Myklebust { 1425a8de240aSTrond Myklebust if (atomic_dec_and_test(&xprt->count)) 1426a8de240aSTrond Myklebust xprt_destroy(xprt); 14276b6ca86bSTrond Myklebust } 1428