11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/net/sunrpc/xprt.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * This is a generic RPC call interface supporting congestion avoidance, 51da177e4SLinus Torvalds * and asynchronous calls. 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * The interface works like this: 81da177e4SLinus Torvalds * 91da177e4SLinus Torvalds * - When a process places a call, it allocates a request slot if 101da177e4SLinus Torvalds * one is available. Otherwise, it sleeps on the backlog queue 111da177e4SLinus Torvalds * (xprt_reserve). 121da177e4SLinus Torvalds * - Next, the caller puts together the RPC message, stuffs it into 1355aa4f58SChuck Lever * the request struct, and calls xprt_transmit(). 1455aa4f58SChuck Lever * - xprt_transmit sends the message and installs the caller on the 1555ae1aabSRicardo Labiaga * transport's wait list. At the same time, if a reply is expected, 1655ae1aabSRicardo Labiaga * it installs a timer that is run after the packet's timeout has 1755ae1aabSRicardo Labiaga * expired. 181da177e4SLinus Torvalds * - When a packet arrives, the data_ready handler walks the list of 1955aa4f58SChuck Lever * pending requests for that transport. If a matching XID is found, the 201da177e4SLinus Torvalds * caller is woken up, and the timer removed. 211da177e4SLinus Torvalds * - When no reply arrives within the timeout interval, the timer is 221da177e4SLinus Torvalds * fired by the kernel and runs xprt_timer(). It either adjusts the 231da177e4SLinus Torvalds * timeout values (minor timeout) or wakes up the caller with a status 241da177e4SLinus Torvalds * of -ETIMEDOUT. 251da177e4SLinus Torvalds * - When the caller receives a notification from RPC that a reply arrived, 261da177e4SLinus Torvalds * it should release the RPC slot, and process the reply. 271da177e4SLinus Torvalds * If the call timed out, it may choose to retry the operation by 281da177e4SLinus Torvalds * adjusting the initial timeout value, and simply calling rpc_call 291da177e4SLinus Torvalds * again. 301da177e4SLinus Torvalds * 311da177e4SLinus Torvalds * Support for async RPC is done through a set of RPC-specific scheduling 321da177e4SLinus Torvalds * primitives that `transparently' work for processes as well as async 331da177e4SLinus Torvalds * tasks that rely on callbacks. 341da177e4SLinus Torvalds * 351da177e4SLinus Torvalds * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> 3655aa4f58SChuck Lever * 3755aa4f58SChuck Lever * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> 381da177e4SLinus Torvalds */ 391da177e4SLinus Torvalds 40a246b010SChuck Lever #include <linux/module.h> 41a246b010SChuck Lever 421da177e4SLinus Torvalds #include <linux/types.h> 43a246b010SChuck Lever #include <linux/interrupt.h> 441da177e4SLinus Torvalds #include <linux/workqueue.h> 45bf3fcf89SChuck Lever #include <linux/net.h> 46ff839970SChuck Lever #include <linux/ktime.h> 471da177e4SLinus Torvalds 48a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 4911c556b3SChuck Lever #include <linux/sunrpc/metrics.h> 50c9acb42eSTrond Myklebust #include <linux/sunrpc/bc_xprt.h> 51fda1bfefSTrond Myklebust #include <linux/rcupdate.h> 521da177e4SLinus Torvalds 533705ad64SJeff Layton #include <trace/events/sunrpc.h> 543705ad64SJeff Layton 5555ae1aabSRicardo Labiaga #include "sunrpc.h" 5655ae1aabSRicardo Labiaga 571da177e4SLinus Torvalds /* 581da177e4SLinus Torvalds * Local variables 591da177e4SLinus Torvalds */ 601da177e4SLinus Torvalds 61f895b252SJeff Layton #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 621da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 631da177e4SLinus Torvalds #endif 641da177e4SLinus Torvalds 651da177e4SLinus Torvalds /* 661da177e4SLinus Torvalds * Local functions 671da177e4SLinus Torvalds */ 6821de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 6937ac86c3SChuck Lever static __be32 xprt_alloc_xid(struct rpc_xprt *xprt); 701da177e4SLinus Torvalds static void xprt_connect_status(struct rpc_task *task); 711da177e4SLinus Torvalds static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); 7229807318SNeil Brown static void __xprt_put_cong(struct rpc_xprt *, struct rpc_rqst *); 734e0038b6STrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt); 741da177e4SLinus Torvalds 755ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7681c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7781c098afS\"Talpey, Thomas\ 7812a80469SChuck Lever /** 7981c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 8081c098afS\"Talpey, Thomas\ * @transport: transport to register 8181c098afS\"Talpey, Thomas\ * 8281c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 8381c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 8481c098afS\"Talpey, Thomas\ * 8581c098afS\"Talpey, Thomas\ * Returns: 8681c098afS\"Talpey, Thomas\ * 0: transport successfully registered 8781c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 8881c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 8981c098afS\"Talpey, Thomas\ */ 9081c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 9181c098afS\"Talpey, Thomas\ { 9281c098afS\"Talpey, Thomas\ struct xprt_class *t; 9381c098afS\"Talpey, Thomas\ int result; 9481c098afS\"Talpey, Thomas\ 9581c098afS\"Talpey, Thomas\ result = -EEXIST; 9681c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 9781c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 9881c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 994fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 10081c098afS\"Talpey, Thomas\ goto out; 10181c098afS\"Talpey, Thomas\ } 10281c098afS\"Talpey, Thomas\ 10381c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 10481c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 10581c098afS\"Talpey, Thomas\ transport->name); 10681c098afS\"Talpey, Thomas\ result = 0; 10781c098afS\"Talpey, Thomas\ 10881c098afS\"Talpey, Thomas\ out: 10981c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 11081c098afS\"Talpey, Thomas\ return result; 11181c098afS\"Talpey, Thomas\ } 11281c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 11381c098afS\"Talpey, Thomas\ 11481c098afS\"Talpey, Thomas\ /** 11581c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 11665b6e42cSRandy Dunlap * @transport: transport to unregister 11781c098afS\"Talpey, Thomas\ * 11881c098afS\"Talpey, Thomas\ * Returns: 11981c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 12081c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 12181c098afS\"Talpey, Thomas\ */ 12281c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 12381c098afS\"Talpey, Thomas\ { 12481c098afS\"Talpey, Thomas\ struct xprt_class *t; 12581c098afS\"Talpey, Thomas\ int result; 12681c098afS\"Talpey, Thomas\ 12781c098afS\"Talpey, Thomas\ result = 0; 12881c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 12981c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 13081c098afS\"Talpey, Thomas\ if (t == transport) { 13181c098afS\"Talpey, Thomas\ printk(KERN_INFO 13281c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 13381c098afS\"Talpey, Thomas\ transport->name); 13481c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 13581c098afS\"Talpey, Thomas\ goto out; 13681c098afS\"Talpey, Thomas\ } 13781c098afS\"Talpey, Thomas\ } 13881c098afS\"Talpey, Thomas\ result = -ENOENT; 13981c098afS\"Talpey, Thomas\ 14081c098afS\"Talpey, Thomas\ out: 14181c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 14281c098afS\"Talpey, Thomas\ return result; 14381c098afS\"Talpey, Thomas\ } 14481c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 14581c098afS\"Talpey, Thomas\ 14681c098afS\"Talpey, Thomas\ /** 147441e3e24STom Talpey * xprt_load_transport - load a transport implementation 148441e3e24STom Talpey * @transport_name: transport to load 149441e3e24STom Talpey * 150441e3e24STom Talpey * Returns: 151441e3e24STom Talpey * 0: transport successfully loaded 152441e3e24STom Talpey * -ENOENT: transport module not available 153441e3e24STom Talpey */ 154441e3e24STom Talpey int xprt_load_transport(const char *transport_name) 155441e3e24STom Talpey { 156441e3e24STom Talpey struct xprt_class *t; 157441e3e24STom Talpey int result; 158441e3e24STom Talpey 159441e3e24STom Talpey result = 0; 160441e3e24STom Talpey spin_lock(&xprt_list_lock); 161441e3e24STom Talpey list_for_each_entry(t, &xprt_list, list) { 162441e3e24STom Talpey if (strcmp(t->name, transport_name) == 0) { 163441e3e24STom Talpey spin_unlock(&xprt_list_lock); 164441e3e24STom Talpey goto out; 165441e3e24STom Talpey } 166441e3e24STom Talpey } 167441e3e24STom Talpey spin_unlock(&xprt_list_lock); 168ef7ffe8fSAlex Riesen result = request_module("xprt%s", transport_name); 169441e3e24STom Talpey out: 170441e3e24STom Talpey return result; 171441e3e24STom Talpey } 172441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 173441e3e24STom Talpey 174441e3e24STom Talpey /** 17512a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 17612a80469SChuck Lever * @task: task that is requesting access to the transport 177177c27bfSRandy Dunlap * @xprt: pointer to the target transport 17812a80469SChuck Lever * 17912a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 18012a80469SChuck Lever * transport connects from colliding with writes. No congestion control 18112a80469SChuck Lever * is provided. 1821da177e4SLinus Torvalds */ 18343cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 1841da177e4SLinus Torvalds { 18512a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 18634006ceeSTrond Myklebust int priority; 18712a80469SChuck Lever 18812a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 18912a80469SChuck Lever if (task == xprt->snd_task) 19012a80469SChuck Lever return 1; 19112a80469SChuck Lever goto out_sleep; 19212a80469SChuck Lever } 19312a80469SChuck Lever xprt->snd_task = task; 1944d4a76f3Sj223yang@asset.uwaterloo.ca 19512a80469SChuck Lever return 1; 19612a80469SChuck Lever 19712a80469SChuck Lever out_sleep: 19846121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", 19912a80469SChuck Lever task->tk_pid, xprt); 20012a80469SChuck Lever task->tk_timeout = 0; 20112a80469SChuck Lever task->tk_status = -EAGAIN; 20234006ceeSTrond Myklebust if (req == NULL) 20334006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 20434006ceeSTrond Myklebust else if (!req->rq_ntrans) 20534006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 20612a80469SChuck Lever else 20734006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 20834006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 20912a80469SChuck Lever return 0; 21012a80469SChuck Lever } 21112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 21212a80469SChuck Lever 213632e3bdcSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 214632e3bdcSTrond Myklebust { 215632e3bdcSTrond Myklebust xprt->snd_task = NULL; 216d19751e7STrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 2174e857c58SPeter Zijlstra smp_mb__before_atomic(); 218632e3bdcSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 2194e857c58SPeter Zijlstra smp_mb__after_atomic(); 220632e3bdcSTrond Myklebust } else 22140a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 222632e3bdcSTrond Myklebust } 223632e3bdcSTrond Myklebust 22412a80469SChuck Lever /* 22512a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 22612a80469SChuck Lever * @task: task that is requesting access to the transport 22712a80469SChuck Lever * 22812a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 22912a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 23012a80469SChuck Lever * woken up and given access to the transport. 23112a80469SChuck Lever */ 23243cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 23312a80469SChuck Lever { 2341da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 23534006ceeSTrond Myklebust int priority; 2361da177e4SLinus Torvalds 2372226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 2381da177e4SLinus Torvalds if (task == xprt->snd_task) 2391da177e4SLinus Torvalds return 1; 2401da177e4SLinus Torvalds goto out_sleep; 2411da177e4SLinus Torvalds } 24243cedbf0STrond Myklebust if (req == NULL) { 24343cedbf0STrond Myklebust xprt->snd_task = task; 24443cedbf0STrond Myklebust return 1; 24543cedbf0STrond Myklebust } 24612a80469SChuck Lever if (__xprt_get_cong(xprt, task)) { 2471da177e4SLinus Torvalds xprt->snd_task = task; 2481da177e4SLinus Torvalds return 1; 2491da177e4SLinus Torvalds } 250632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 2511da177e4SLinus Torvalds out_sleep: 25229807318SNeil Brown if (req) 25329807318SNeil Brown __xprt_put_cong(xprt, req); 25446121cf7SChuck Lever dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); 2551da177e4SLinus Torvalds task->tk_timeout = 0; 2561da177e4SLinus Torvalds task->tk_status = -EAGAIN; 25734006ceeSTrond Myklebust if (req == NULL) 25834006ceeSTrond Myklebust priority = RPC_PRIORITY_LOW; 25934006ceeSTrond Myklebust else if (!req->rq_ntrans) 26034006ceeSTrond Myklebust priority = RPC_PRIORITY_NORMAL; 2611da177e4SLinus Torvalds else 26234006ceeSTrond Myklebust priority = RPC_PRIORITY_HIGH; 26334006ceeSTrond Myklebust rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); 2641da177e4SLinus Torvalds return 0; 2651da177e4SLinus Torvalds } 26612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 2671da177e4SLinus Torvalds 26812a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 2691da177e4SLinus Torvalds { 2701da177e4SLinus Torvalds int retval; 2711da177e4SLinus Torvalds 2724a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 27343cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 2744a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 2751da177e4SLinus Torvalds return retval; 2761da177e4SLinus Torvalds } 2771da177e4SLinus Torvalds 278961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 2791da177e4SLinus Torvalds { 280961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 28149e9a890SChuck Lever 28249e9a890SChuck Lever xprt->snd_task = task; 283961a828dSTrond Myklebust return true; 284961a828dSTrond Myklebust } 285961a828dSTrond Myklebust 286961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 287961a828dSTrond Myklebust { 288961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 28949e9a890SChuck Lever return; 29049e9a890SChuck Lever 291f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 292f1dc237cSTrond Myklebust __xprt_lock_write_func, xprt)) 293961a828dSTrond Myklebust return; 294632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 29549e9a890SChuck Lever } 29649e9a890SChuck Lever 297961a828dSTrond Myklebust static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) 29849e9a890SChuck Lever { 299961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 30043cedbf0STrond Myklebust struct rpc_rqst *req; 3011da177e4SLinus Torvalds 30243cedbf0STrond Myklebust req = task->tk_rqstp; 30343cedbf0STrond Myklebust if (req == NULL) { 3041da177e4SLinus Torvalds xprt->snd_task = task; 305961a828dSTrond Myklebust return true; 30643cedbf0STrond Myklebust } 30743cedbf0STrond Myklebust if (__xprt_get_cong(xprt, task)) { 30843cedbf0STrond Myklebust xprt->snd_task = task; 3091da177e4SLinus Torvalds req->rq_ntrans++; 310961a828dSTrond Myklebust return true; 3111da177e4SLinus Torvalds } 312961a828dSTrond Myklebust return false; 313961a828dSTrond Myklebust } 314961a828dSTrond Myklebust 315961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 316961a828dSTrond Myklebust { 317961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 318961a828dSTrond Myklebust return; 319961a828dSTrond Myklebust if (RPCXPRT_CONGESTED(xprt)) 320961a828dSTrond Myklebust goto out_unlock; 321f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 322f1dc237cSTrond Myklebust __xprt_lock_write_cong_func, xprt)) 323961a828dSTrond Myklebust return; 3241da177e4SLinus Torvalds out_unlock: 325632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3261da177e4SLinus Torvalds } 3271da177e4SLinus Torvalds 32849e9a890SChuck Lever /** 32949e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 33049e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 33149e9a890SChuck Lever * @task: task that is releasing access to the transport 33249e9a890SChuck Lever * 33349e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 3341da177e4SLinus Torvalds */ 33549e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 3361da177e4SLinus Torvalds { 3371da177e4SLinus Torvalds if (xprt->snd_task == task) { 338632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3391da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 3401da177e4SLinus Torvalds } 3411da177e4SLinus Torvalds } 34212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 3431da177e4SLinus Torvalds 34449e9a890SChuck Lever /** 34549e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 34649e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 34749e9a890SChuck Lever * @task: task that is releasing access to the transport 34849e9a890SChuck Lever * 34949e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 35049e9a890SChuck Lever * transport if the transport's congestion window allows it. 35149e9a890SChuck Lever */ 35249e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 35349e9a890SChuck Lever { 35449e9a890SChuck Lever if (xprt->snd_task == task) { 355632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 35649e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 35749e9a890SChuck Lever } 35849e9a890SChuck Lever } 35912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 36049e9a890SChuck Lever 36149e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 3621da177e4SLinus Torvalds { 3634a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 36449e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 3654a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 3661da177e4SLinus Torvalds } 3671da177e4SLinus Torvalds 3681da177e4SLinus Torvalds /* 3691da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 3701da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 3711da177e4SLinus Torvalds */ 3721da177e4SLinus Torvalds static int 3731da177e4SLinus Torvalds __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) 3741da177e4SLinus Torvalds { 3751da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3761da177e4SLinus Torvalds 3771da177e4SLinus Torvalds if (req->rq_cong) 3781da177e4SLinus Torvalds return 1; 37946121cf7SChuck Lever dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", 3801da177e4SLinus Torvalds task->tk_pid, xprt->cong, xprt->cwnd); 3811da177e4SLinus Torvalds if (RPCXPRT_CONGESTED(xprt)) 3821da177e4SLinus Torvalds return 0; 3831da177e4SLinus Torvalds req->rq_cong = 1; 3841da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 3851da177e4SLinus Torvalds return 1; 3861da177e4SLinus Torvalds } 3871da177e4SLinus Torvalds 3881da177e4SLinus Torvalds /* 3891da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 3901da177e4SLinus Torvalds * that has been sleeping due to congestion 3911da177e4SLinus Torvalds */ 3921da177e4SLinus Torvalds static void 3931da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 3941da177e4SLinus Torvalds { 3951da177e4SLinus Torvalds if (!req->rq_cong) 3961da177e4SLinus Torvalds return; 3971da177e4SLinus Torvalds req->rq_cong = 0; 3981da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 39949e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4001da177e4SLinus Torvalds } 4011da177e4SLinus Torvalds 40246c0ee8bSChuck Lever /** 403a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 404a58dd398SChuck Lever * @task: RPC request that recently completed 405a58dd398SChuck Lever * 406a58dd398SChuck Lever * Useful for transports that require congestion control. 407a58dd398SChuck Lever */ 408a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 409a58dd398SChuck Lever { 410a4f0835cSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 411a4f0835cSTrond Myklebust 412a4f0835cSTrond Myklebust __xprt_put_cong(req->rq_xprt, req); 413a58dd398SChuck Lever } 41412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 415a58dd398SChuck Lever 416a58dd398SChuck Lever /** 41746c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 4186a24dfb6STrond Myklebust * @xprt: pointer to xprt 41946c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 42046c0ee8bSChuck Lever * @result: result code of completed RPC request 42146c0ee8bSChuck Lever * 4224f4cf5adSChuck Lever * The transport code maintains an estimate on the maximum number of out- 4234f4cf5adSChuck Lever * standing RPC requests, using a smoothed version of the congestion 4244f4cf5adSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 4254f4cf5adSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 4264f4cf5adSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 4274f4cf5adSChuck Lever * 4284f4cf5adSChuck Lever * - a reply is received and 4294f4cf5adSChuck Lever * - a full number of requests are outstanding and 4304f4cf5adSChuck Lever * - the congestion window hasn't been updated recently. 4311da177e4SLinus Torvalds */ 4326a24dfb6STrond Myklebust void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) 4331da177e4SLinus Torvalds { 43446c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 43546c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 4361da177e4SLinus Torvalds 4371da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 4381da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 4391da177e4SLinus Torvalds * the result gets rounded properly. */ 4401da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 4411da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 4421da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 44349e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4441da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 4451da177e4SLinus Torvalds cwnd >>= 1; 4461da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 4471da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 4481da177e4SLinus Torvalds } 4491da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 4501da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 4511da177e4SLinus Torvalds xprt->cwnd = cwnd; 45246c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 4531da177e4SLinus Torvalds } 45412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 4551da177e4SLinus Torvalds 45644fbac22SChuck Lever /** 45744fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 45844fbac22SChuck Lever * @xprt: transport with waiting tasks 45944fbac22SChuck Lever * @status: result code to plant in each task before waking it 46044fbac22SChuck Lever * 46144fbac22SChuck Lever */ 46244fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 46344fbac22SChuck Lever { 46444fbac22SChuck Lever if (status < 0) 46544fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 46644fbac22SChuck Lever else 46744fbac22SChuck Lever rpc_wake_up(&xprt->pending); 46844fbac22SChuck Lever } 46912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 47044fbac22SChuck Lever 471c7b2cae8SChuck Lever /** 472c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 473c7b2cae8SChuck Lever * @task: task to be put to sleep 4740b80ae42SRandy Dunlap * @action: function pointer to be executed after wait 475a9a6b52eSTrond Myklebust * 476a9a6b52eSTrond Myklebust * Note that we only set the timer for the case of RPC_IS_SOFT(), since 477a9a6b52eSTrond Myklebust * we don't in general want to force a socket disconnection due to 478a9a6b52eSTrond Myklebust * an incomplete RPC call transmission. 479c7b2cae8SChuck Lever */ 480b6ddf64fSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) 481c7b2cae8SChuck Lever { 482c7b2cae8SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 483c7b2cae8SChuck Lever struct rpc_xprt *xprt = req->rq_xprt; 484c7b2cae8SChuck Lever 485a9a6b52eSTrond Myklebust task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; 486b6ddf64fSTrond Myklebust rpc_sleep_on(&xprt->pending, task, action); 487c7b2cae8SChuck Lever } 48812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 489c7b2cae8SChuck Lever 490c7b2cae8SChuck Lever /** 491c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 492c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 493c7b2cae8SChuck Lever * 494c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 495c7b2cae8SChuck Lever */ 496c7b2cae8SChuck Lever void xprt_write_space(struct rpc_xprt *xprt) 497c7b2cae8SChuck Lever { 498c7b2cae8SChuck Lever spin_lock_bh(&xprt->transport_lock); 499c7b2cae8SChuck Lever if (xprt->snd_task) { 50046121cf7SChuck Lever dprintk("RPC: write space: waking waiting task on " 50146121cf7SChuck Lever "xprt %p\n", xprt); 5022275cde4STrond Myklebust rpc_wake_up_queued_task_on_wq(xprtiod_workqueue, 5032275cde4STrond Myklebust &xprt->pending, xprt->snd_task); 504c7b2cae8SChuck Lever } 505c7b2cae8SChuck Lever spin_unlock_bh(&xprt->transport_lock); 506c7b2cae8SChuck Lever } 50712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 508c7b2cae8SChuck Lever 509fe3aca29SChuck Lever /** 510fe3aca29SChuck Lever * xprt_set_retrans_timeout_def - set a request's retransmit timeout 511fe3aca29SChuck Lever * @task: task whose timeout is to be set 512fe3aca29SChuck Lever * 513fe3aca29SChuck Lever * Set a request's retransmit timeout based on the transport's 514fe3aca29SChuck Lever * default timeout parameters. Used by transports that don't adjust 515fe3aca29SChuck Lever * the retransmit timeout based on round-trip time estimation. 516fe3aca29SChuck Lever */ 517fe3aca29SChuck Lever void xprt_set_retrans_timeout_def(struct rpc_task *task) 518fe3aca29SChuck Lever { 519fe3aca29SChuck Lever task->tk_timeout = task->tk_rqstp->rq_timeout; 520fe3aca29SChuck Lever } 52112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); 522fe3aca29SChuck Lever 5232c53040fSBen Hutchings /** 524fe3aca29SChuck Lever * xprt_set_retrans_timeout_rtt - 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 using the RTT estimator. 528fe3aca29SChuck Lever */ 529fe3aca29SChuck Lever void xprt_set_retrans_timeout_rtt(struct rpc_task *task) 530fe3aca29SChuck Lever { 531fe3aca29SChuck Lever int timer = task->tk_msg.rpc_proc->p_timer; 532ba7392bbSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 533ba7392bbSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 534fe3aca29SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 535ba7392bbSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 536fe3aca29SChuck Lever 537fe3aca29SChuck Lever task->tk_timeout = rpc_calc_rto(rtt, timer); 538fe3aca29SChuck Lever task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 539fe3aca29SChuck Lever if (task->tk_timeout > max_timeout || task->tk_timeout == 0) 540fe3aca29SChuck Lever task->tk_timeout = max_timeout; 541fe3aca29SChuck Lever } 54212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); 543fe3aca29SChuck Lever 5441da177e4SLinus Torvalds static void xprt_reset_majortimeo(struct rpc_rqst *req) 5451da177e4SLinus Torvalds { 546ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5471da177e4SLinus Torvalds 5481da177e4SLinus Torvalds req->rq_majortimeo = req->rq_timeout; 5491da177e4SLinus Torvalds if (to->to_exponential) 5501da177e4SLinus Torvalds req->rq_majortimeo <<= to->to_retries; 5511da177e4SLinus Torvalds else 5521da177e4SLinus Torvalds req->rq_majortimeo += to->to_increment * to->to_retries; 5531da177e4SLinus Torvalds if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) 5541da177e4SLinus Torvalds req->rq_majortimeo = to->to_maxval; 5551da177e4SLinus Torvalds req->rq_majortimeo += jiffies; 5561da177e4SLinus Torvalds } 5571da177e4SLinus Torvalds 5589903cd1cSChuck Lever /** 5599903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 5609903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 5619903cd1cSChuck Lever * 5621da177e4SLinus Torvalds */ 5631da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 5641da177e4SLinus Torvalds { 5651da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 566ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 5671da177e4SLinus Torvalds int status = 0; 5681da177e4SLinus Torvalds 5691da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 5701da177e4SLinus Torvalds if (to->to_exponential) 5711da177e4SLinus Torvalds req->rq_timeout <<= 1; 5721da177e4SLinus Torvalds else 5731da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 5741da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 5751da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 5761da177e4SLinus Torvalds req->rq_retries++; 5771da177e4SLinus Torvalds } else { 5781da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 5791da177e4SLinus Torvalds req->rq_retries = 0; 5801da177e4SLinus Torvalds xprt_reset_majortimeo(req); 5811da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 5824a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 5831da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 5844a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 5851da177e4SLinus Torvalds status = -ETIMEDOUT; 5861da177e4SLinus Torvalds } 5871da177e4SLinus Torvalds 5881da177e4SLinus Torvalds if (req->rq_timeout == 0) { 5891da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 5901da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 5911da177e4SLinus Torvalds } 5921da177e4SLinus Torvalds return status; 5931da177e4SLinus Torvalds } 5941da177e4SLinus Torvalds 59565f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 5961da177e4SLinus Torvalds { 59765f27f38SDavid Howells struct rpc_xprt *xprt = 59865f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 5991da177e4SLinus Torvalds 60066af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 6014876cc77STrond Myklebust xprt->ops->close(xprt); 6021da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 60379234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 6041da177e4SLinus Torvalds } 6051da177e4SLinus Torvalds 6069903cd1cSChuck Lever /** 60762da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 6089903cd1cSChuck Lever * @xprt: transport to flag for disconnect 6099903cd1cSChuck Lever * 6101da177e4SLinus Torvalds */ 61162da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 6121da177e4SLinus Torvalds { 6131da177e4SLinus Torvalds dprintk("RPC: disconnected transport %p\n", xprt); 6144a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 6151da177e4SLinus Torvalds xprt_clear_connected(xprt); 6162a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6174a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 6181da177e4SLinus Torvalds } 61962da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 6201da177e4SLinus Torvalds 62166af1e55STrond Myklebust /** 62266af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 62366af1e55STrond Myklebust * @xprt: transport to disconnect 62466af1e55STrond Myklebust * 62566af1e55STrond Myklebust */ 62666af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 62766af1e55STrond Myklebust { 62866af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 62966af1e55STrond Myklebust spin_lock_bh(&xprt->transport_lock); 63066af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 63166af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 63266af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 63340a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 6342a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 63566af1e55STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 63666af1e55STrond Myklebust } 637e2a4f4fbSChuck Lever EXPORT_SYMBOL_GPL(xprt_force_disconnect); 63866af1e55STrond Myklebust 6397f3a1d1eSTrond Myklebust static unsigned int 6407f3a1d1eSTrond Myklebust xprt_connect_cookie(struct rpc_xprt *xprt) 6417f3a1d1eSTrond Myklebust { 6427f3a1d1eSTrond Myklebust return READ_ONCE(xprt->connect_cookie); 6437f3a1d1eSTrond Myklebust } 6447f3a1d1eSTrond Myklebust 6457f3a1d1eSTrond Myklebust static bool 6467f3a1d1eSTrond Myklebust xprt_request_retransmit_after_disconnect(struct rpc_task *task) 6477f3a1d1eSTrond Myklebust { 6487f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 6497f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 6507f3a1d1eSTrond Myklebust 6517f3a1d1eSTrond Myklebust return req->rq_connect_cookie != xprt_connect_cookie(xprt) || 6527f3a1d1eSTrond Myklebust !xprt_connected(xprt); 6537f3a1d1eSTrond Myklebust } 6547f3a1d1eSTrond Myklebust 6557c1d71cfSTrond Myklebust /** 6567c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 6577c1d71cfSTrond Myklebust * @xprt: transport to disconnect 6587c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 6597c1d71cfSTrond Myklebust * 6607c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 6617c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 6627c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 6637c1d71cfSTrond Myklebust * a batch of RPC requests. 6647c1d71cfSTrond Myklebust * 6657c1d71cfSTrond Myklebust */ 6667c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 6677c1d71cfSTrond Myklebust { 6687c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 6697c1d71cfSTrond Myklebust spin_lock_bh(&xprt->transport_lock); 6707c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 6717c1d71cfSTrond Myklebust goto out; 6722c2ee6d2SNeilBrown if (test_bit(XPRT_CLOSING, &xprt->state)) 6737c1d71cfSTrond Myklebust goto out; 6747c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 6757c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 6767c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 67740a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 6782a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 6797c1d71cfSTrond Myklebust out: 6807c1d71cfSTrond Myklebust spin_unlock_bh(&xprt->transport_lock); 6817c1d71cfSTrond Myklebust } 6827c1d71cfSTrond Myklebust 683ad3331acSTrond Myklebust static bool 684ad3331acSTrond Myklebust xprt_has_timer(const struct rpc_xprt *xprt) 685ad3331acSTrond Myklebust { 686ad3331acSTrond Myklebust return xprt->idle_timeout != 0; 687ad3331acSTrond Myklebust } 688ad3331acSTrond Myklebust 689ad3331acSTrond Myklebust static void 690ad3331acSTrond Myklebust xprt_schedule_autodisconnect(struct rpc_xprt *xprt) 691ad3331acSTrond Myklebust __must_hold(&xprt->transport_lock) 692ad3331acSTrond Myklebust { 693ef3f5434STrond Myklebust if (list_empty(&xprt->recv_queue) && xprt_has_timer(xprt)) 694ad3331acSTrond Myklebust mod_timer(&xprt->timer, xprt->last_used + xprt->idle_timeout); 695ad3331acSTrond Myklebust } 696ad3331acSTrond Myklebust 6971da177e4SLinus Torvalds static void 698ff861c4dSKees Cook xprt_init_autodisconnect(struct timer_list *t) 6991da177e4SLinus Torvalds { 700ff861c4dSKees Cook struct rpc_xprt *xprt = from_timer(xprt, t, timer); 7011da177e4SLinus Torvalds 7024a0f8c04SChuck Lever spin_lock(&xprt->transport_lock); 703ef3f5434STrond Myklebust if (!list_empty(&xprt->recv_queue)) 7041da177e4SLinus Torvalds goto out_abort; 705ad3331acSTrond Myklebust /* Reset xprt->last_used to avoid connect/autodisconnect cycling */ 706ad3331acSTrond Myklebust xprt->last_used = jiffies; 7072226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 7081da177e4SLinus Torvalds goto out_abort; 7094a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 71040a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 7111da177e4SLinus Torvalds return; 7121da177e4SLinus Torvalds out_abort: 7134a0f8c04SChuck Lever spin_unlock(&xprt->transport_lock); 7141da177e4SLinus Torvalds } 7151da177e4SLinus Torvalds 716718ba5b8STrond Myklebust bool xprt_lock_connect(struct rpc_xprt *xprt, 717718ba5b8STrond Myklebust struct rpc_task *task, 718718ba5b8STrond Myklebust void *cookie) 719718ba5b8STrond Myklebust { 720718ba5b8STrond Myklebust bool ret = false; 721718ba5b8STrond Myklebust 722718ba5b8STrond Myklebust spin_lock_bh(&xprt->transport_lock); 723718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 724718ba5b8STrond Myklebust goto out; 725718ba5b8STrond Myklebust if (xprt->snd_task != task) 726718ba5b8STrond Myklebust goto out; 727718ba5b8STrond Myklebust xprt->snd_task = cookie; 728718ba5b8STrond Myklebust ret = true; 729718ba5b8STrond Myklebust out: 730718ba5b8STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 731718ba5b8STrond Myklebust return ret; 732718ba5b8STrond Myklebust } 733718ba5b8STrond Myklebust 734718ba5b8STrond Myklebust void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) 735718ba5b8STrond Myklebust { 736718ba5b8STrond Myklebust spin_lock_bh(&xprt->transport_lock); 737718ba5b8STrond Myklebust if (xprt->snd_task != cookie) 738718ba5b8STrond Myklebust goto out; 739718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 740718ba5b8STrond Myklebust goto out; 741718ba5b8STrond Myklebust xprt->snd_task =NULL; 742718ba5b8STrond Myklebust xprt->ops->release_xprt(xprt, NULL); 743ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 744718ba5b8STrond Myklebust out: 745718ba5b8STrond Myklebust spin_unlock_bh(&xprt->transport_lock); 74679234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 747718ba5b8STrond Myklebust } 748718ba5b8STrond Myklebust 7499903cd1cSChuck Lever /** 7509903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 7519903cd1cSChuck Lever * @task: RPC task that is requesting the connect 7521da177e4SLinus Torvalds * 7531da177e4SLinus Torvalds */ 7541da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 7551da177e4SLinus Torvalds { 756ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 7571da177e4SLinus Torvalds 75846121cf7SChuck Lever dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, 7591da177e4SLinus Torvalds xprt, (xprt_connected(xprt) ? "is" : "is not")); 7601da177e4SLinus Torvalds 761ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 76201d37c42STrond Myklebust task->tk_status = -EAGAIN; 7631da177e4SLinus Torvalds return; 7641da177e4SLinus Torvalds } 7651da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 7661da177e4SLinus Torvalds return; 767feb8ca37STrond Myklebust 768feb8ca37STrond Myklebust if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) 769feb8ca37STrond Myklebust xprt->ops->close(xprt); 770feb8ca37STrond Myklebust 771718ba5b8STrond Myklebust if (!xprt_connected(xprt)) { 772a8ce4a8fSTrond Myklebust task->tk_timeout = task->tk_rqstp->rq_timeout; 7732c2ee6d2SNeilBrown task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie; 7745d00837bSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_connect_status); 7750b9e7943STrond Myklebust 7760b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 7770b9e7943STrond Myklebust return; 7780b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 7790b9e7943STrond Myklebust return; 780262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 7811b092092STrond Myklebust xprt->ops->connect(xprt, task); 7821da177e4SLinus Torvalds } 783718ba5b8STrond Myklebust xprt_release_write(xprt, task); 7841da177e4SLinus Torvalds } 7851da177e4SLinus Torvalds 7869903cd1cSChuck Lever static void xprt_connect_status(struct rpc_task *task) 7871da177e4SLinus Torvalds { 788ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 7891da177e4SLinus Torvalds 790cd983ef8SChuck Lever if (task->tk_status == 0) { 791262ca07dSChuck Lever xprt->stat.connect_count++; 792262ca07dSChuck Lever xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; 79346121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connection established\n", 7941da177e4SLinus Torvalds task->tk_pid); 7951da177e4SLinus Torvalds return; 7961da177e4SLinus Torvalds } 7971da177e4SLinus Torvalds 7981da177e4SLinus Torvalds switch (task->tk_status) { 7990fe8d04eSTrond Myklebust case -ECONNREFUSED: 8000fe8d04eSTrond Myklebust case -ECONNRESET: 8010fe8d04eSTrond Myklebust case -ECONNABORTED: 8020fe8d04eSTrond Myklebust case -ENETUNREACH: 8030fe8d04eSTrond Myklebust case -EHOSTUNREACH: 8042fc193cfSTrond Myklebust case -EPIPE: 8052a491991STrond Myklebust case -EAGAIN: 8062a491991STrond Myklebust dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); 80723475d66SChuck Lever break; 8081da177e4SLinus Torvalds case -ETIMEDOUT: 80946121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: connect attempt timed " 81046121cf7SChuck Lever "out\n", task->tk_pid); 8111da177e4SLinus Torvalds break; 8121da177e4SLinus Torvalds default: 81346121cf7SChuck Lever dprintk("RPC: %5u xprt_connect_status: error %d connecting to " 81446121cf7SChuck Lever "server %s\n", task->tk_pid, -task->tk_status, 8154e0038b6STrond Myklebust xprt->servername); 81623475d66SChuck Lever task->tk_status = -EIO; 81723475d66SChuck Lever } 8181da177e4SLinus Torvalds } 8191da177e4SLinus Torvalds 8209903cd1cSChuck Lever /** 8219903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 8229903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 8239903cd1cSChuck Lever * @xid: RPC XID of incoming reply 8249903cd1cSChuck Lever * 82575c84151STrond Myklebust * Caller holds xprt->queue_lock. 8261da177e4SLinus Torvalds */ 827d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 8281da177e4SLinus Torvalds { 8298f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 8301da177e4SLinus Torvalds 831ef3f5434STrond Myklebust list_for_each_entry(entry, &xprt->recv_queue, rq_recv) 8323705ad64SJeff Layton if (entry->rq_xid == xid) { 8333705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, 0); 8340b87a46bSChuck Lever entry->rq_rtt = ktime_sub(ktime_get(), entry->rq_xtime); 835262ca07dSChuck Lever return entry; 8363705ad64SJeff Layton } 83746121cf7SChuck Lever 83846121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 83946121cf7SChuck Lever ntohl(xid)); 8403705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, -ENOENT); 841262ca07dSChuck Lever xprt->stat.bad_xids++; 842262ca07dSChuck Lever return NULL; 8431da177e4SLinus Torvalds } 84412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 8451da177e4SLinus Torvalds 846cf9946cdSTrond Myklebust static bool 847cf9946cdSTrond Myklebust xprt_is_pinned_rqst(struct rpc_rqst *req) 848cf9946cdSTrond Myklebust { 849cf9946cdSTrond Myklebust return atomic_read(&req->rq_pin) != 0; 850cf9946cdSTrond Myklebust } 851cf9946cdSTrond Myklebust 852729749bbSTrond Myklebust /** 853729749bbSTrond Myklebust * xprt_pin_rqst - Pin a request on the transport receive list 854729749bbSTrond Myklebust * @req: Request to pin 855729749bbSTrond Myklebust * 856729749bbSTrond Myklebust * Caller must ensure this is atomic with the call to xprt_lookup_rqst() 857cf9946cdSTrond Myklebust * so should be holding the xprt receive lock. 858729749bbSTrond Myklebust */ 859729749bbSTrond Myklebust void xprt_pin_rqst(struct rpc_rqst *req) 860729749bbSTrond Myklebust { 861cf9946cdSTrond Myklebust atomic_inc(&req->rq_pin); 862729749bbSTrond Myklebust } 8639590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_pin_rqst); 864729749bbSTrond Myklebust 865729749bbSTrond Myklebust /** 866729749bbSTrond Myklebust * xprt_unpin_rqst - Unpin a request on the transport receive list 867729749bbSTrond Myklebust * @req: Request to pin 868729749bbSTrond Myklebust * 869cf9946cdSTrond Myklebust * Caller should be holding the xprt receive lock. 870729749bbSTrond Myklebust */ 871729749bbSTrond Myklebust void xprt_unpin_rqst(struct rpc_rqst *req) 872729749bbSTrond Myklebust { 873cf9946cdSTrond Myklebust if (!test_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate)) { 874cf9946cdSTrond Myklebust atomic_dec(&req->rq_pin); 875cf9946cdSTrond Myklebust return; 876cf9946cdSTrond Myklebust } 877cf9946cdSTrond Myklebust if (atomic_dec_and_test(&req->rq_pin)) 878cf9946cdSTrond Myklebust wake_up_var(&req->rq_pin); 879729749bbSTrond Myklebust } 8809590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_unpin_rqst); 881729749bbSTrond Myklebust 882729749bbSTrond Myklebust static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) 883729749bbSTrond Myklebust { 884cf9946cdSTrond Myklebust wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); 885729749bbSTrond Myklebust } 886729749bbSTrond Myklebust 887edc81dcdSTrond Myklebust static bool 888edc81dcdSTrond Myklebust xprt_request_data_received(struct rpc_task *task) 889edc81dcdSTrond Myklebust { 890edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 891edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; 892edc81dcdSTrond Myklebust } 893edc81dcdSTrond Myklebust 894edc81dcdSTrond Myklebust static bool 895edc81dcdSTrond Myklebust xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst *req) 896edc81dcdSTrond Myklebust { 897edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 898edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) == 0; 899edc81dcdSTrond Myklebust } 900edc81dcdSTrond Myklebust 901edc81dcdSTrond Myklebust /** 902edc81dcdSTrond Myklebust * xprt_request_enqueue_receive - Add an request to the receive queue 903edc81dcdSTrond Myklebust * @task: RPC task 904edc81dcdSTrond Myklebust * 905edc81dcdSTrond Myklebust */ 906edc81dcdSTrond Myklebust void 907edc81dcdSTrond Myklebust xprt_request_enqueue_receive(struct rpc_task *task) 908edc81dcdSTrond Myklebust { 909edc81dcdSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 910edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 911edc81dcdSTrond Myklebust 912edc81dcdSTrond Myklebust if (!xprt_request_need_enqueue_receive(task, req)) 913edc81dcdSTrond Myklebust return; 914edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 915edc81dcdSTrond Myklebust 916edc81dcdSTrond Myklebust /* Update the softirq receive buffer */ 917edc81dcdSTrond Myklebust memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 918edc81dcdSTrond Myklebust sizeof(req->rq_private_buf)); 919edc81dcdSTrond Myklebust 920edc81dcdSTrond Myklebust /* Add request to the receive list */ 921ef3f5434STrond Myklebust list_add_tail(&req->rq_recv, &xprt->recv_queue); 922edc81dcdSTrond Myklebust set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); 923edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 924edc81dcdSTrond Myklebust 925edc81dcdSTrond Myklebust xprt_reset_majortimeo(req); 926edc81dcdSTrond Myklebust /* Turn off autodisconnect */ 927edc81dcdSTrond Myklebust del_singleshot_timer_sync(&xprt->timer); 928edc81dcdSTrond Myklebust } 929edc81dcdSTrond Myklebust 930edc81dcdSTrond Myklebust /** 931edc81dcdSTrond Myklebust * xprt_request_dequeue_receive_locked - Remove a request from the receive queue 932edc81dcdSTrond Myklebust * @task: RPC task 933edc81dcdSTrond Myklebust * 934edc81dcdSTrond Myklebust * Caller must hold xprt->queue_lock. 935edc81dcdSTrond Myklebust */ 936edc81dcdSTrond Myklebust static void 937edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(struct rpc_task *task) 938edc81dcdSTrond Myklebust { 939edc81dcdSTrond Myklebust if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 940ef3f5434STrond Myklebust list_del(&task->tk_rqstp->rq_recv); 941edc81dcdSTrond Myklebust } 942edc81dcdSTrond Myklebust 943ecd465eeSChuck Lever /** 944ecd465eeSChuck Lever * xprt_update_rtt - Update RPC RTT statistics 945ecd465eeSChuck Lever * @task: RPC request that recently completed 946ecd465eeSChuck Lever * 94775c84151STrond Myklebust * Caller holds xprt->queue_lock. 948ecd465eeSChuck Lever */ 949ecd465eeSChuck Lever void xprt_update_rtt(struct rpc_task *task) 9501da177e4SLinus Torvalds { 9511570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 9521570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 95395c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 954d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 9551570c1e4SChuck Lever 9561da177e4SLinus Torvalds if (timer) { 9571da177e4SLinus Torvalds if (req->rq_ntrans == 1) 958ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 9591570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 9601da177e4SLinus Torvalds } 9611da177e4SLinus Torvalds } 962ecd465eeSChuck Lever EXPORT_SYMBOL_GPL(xprt_update_rtt); 9631da177e4SLinus Torvalds 9641570c1e4SChuck Lever /** 9651570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 9661570c1e4SChuck Lever * @task: RPC request that recently completed 9671570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 9681570c1e4SChuck Lever * 96975c84151STrond Myklebust * Caller holds xprt->queue_lock. 9701570c1e4SChuck Lever */ 9711570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 9721570c1e4SChuck Lever { 9731570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 974fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 9751da177e4SLinus Torvalds 9761570c1e4SChuck Lever dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", 9771570c1e4SChuck Lever task->tk_pid, ntohl(req->rq_xid), copied); 9783705ad64SJeff Layton trace_xprt_complete_rqst(xprt, req->rq_xid, copied); 9791da177e4SLinus Torvalds 980fda13939STrond Myklebust xprt->stat.recvs++; 981ef759a2eSChuck Lever 9821e799b67STrond Myklebust req->rq_private_buf.len = copied; 983dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 984dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 98543ac3f29STrond Myklebust smp_wmb(); 986dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 987edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 988fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 9891da177e4SLinus Torvalds } 99012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 9911da177e4SLinus Torvalds 99246c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 9931da177e4SLinus Torvalds { 9941da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 9951da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 9961da177e4SLinus Torvalds 9975d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 9985d00837bSTrond Myklebust return; 99946c0ee8bSChuck Lever 100082476d9fSChuck Lever trace_xprt_timer(xprt, req->rq_xid, task->tk_status); 1001dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 100246c0ee8bSChuck Lever if (xprt->ops->timer) 10036a24dfb6STrond Myklebust xprt->ops->timer(xprt, task); 10045d00837bSTrond Myklebust } else 10055d00837bSTrond Myklebust task->tk_status = 0; 10061da177e4SLinus Torvalds } 10071da177e4SLinus Torvalds 10089903cd1cSChuck Lever /** 10097f3a1d1eSTrond Myklebust * xprt_request_wait_receive - wait for the reply to an RPC request 10107f3a1d1eSTrond Myklebust * @task: RPC task about to send a request 10117f3a1d1eSTrond Myklebust * 10127f3a1d1eSTrond Myklebust */ 10137f3a1d1eSTrond Myklebust void xprt_request_wait_receive(struct rpc_task *task) 10147f3a1d1eSTrond Myklebust { 10157f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 10167f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 10177f3a1d1eSTrond Myklebust 10187f3a1d1eSTrond Myklebust if (!test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 10197f3a1d1eSTrond Myklebust return; 10207f3a1d1eSTrond Myklebust /* 10217f3a1d1eSTrond Myklebust * Sleep on the pending queue if we're expecting a reply. 10227f3a1d1eSTrond Myklebust * The spinlock ensures atomicity between the test of 10237f3a1d1eSTrond Myklebust * req->rq_reply_bytes_recvd, and the call to rpc_sleep_on(). 10247f3a1d1eSTrond Myklebust */ 10257f3a1d1eSTrond Myklebust spin_lock(&xprt->queue_lock); 10267f3a1d1eSTrond Myklebust if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) { 10277f3a1d1eSTrond Myklebust xprt->ops->set_retrans_timeout(task); 10287f3a1d1eSTrond Myklebust rpc_sleep_on(&xprt->pending, task, xprt_timer); 10297f3a1d1eSTrond Myklebust /* 10307f3a1d1eSTrond Myklebust * Send an extra queue wakeup call if the 10317f3a1d1eSTrond Myklebust * connection was dropped in case the call to 10327f3a1d1eSTrond Myklebust * rpc_sleep_on() raced. 10337f3a1d1eSTrond Myklebust */ 10347f3a1d1eSTrond Myklebust if (xprt_request_retransmit_after_disconnect(task)) 10357f3a1d1eSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 10367f3a1d1eSTrond Myklebust task, -ENOTCONN); 10377f3a1d1eSTrond Myklebust } 10387f3a1d1eSTrond Myklebust spin_unlock(&xprt->queue_lock); 10397f3a1d1eSTrond Myklebust } 10407f3a1d1eSTrond Myklebust 1041944b0429STrond Myklebust static bool 1042944b0429STrond Myklebust xprt_request_need_enqueue_transmit(struct rpc_task *task, struct rpc_rqst *req) 1043944b0429STrond Myklebust { 1044762e4e67STrond Myklebust return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1045944b0429STrond Myklebust } 1046944b0429STrond Myklebust 1047944b0429STrond Myklebust /** 1048944b0429STrond Myklebust * xprt_request_enqueue_transmit - queue a task for transmission 1049944b0429STrond Myklebust * @task: pointer to rpc_task 1050944b0429STrond Myklebust * 1051944b0429STrond Myklebust * Add a task to the transmission queue. 1052944b0429STrond Myklebust */ 1053944b0429STrond Myklebust void 1054944b0429STrond Myklebust xprt_request_enqueue_transmit(struct rpc_task *task) 1055944b0429STrond Myklebust { 1056944b0429STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1057944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1058944b0429STrond Myklebust 1059944b0429STrond Myklebust if (xprt_request_need_enqueue_transmit(task, req)) { 1060944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 1061944b0429STrond Myklebust list_add_tail(&req->rq_xmit, &xprt->xmit_queue); 1062944b0429STrond Myklebust set_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1063944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1064944b0429STrond Myklebust } 1065944b0429STrond Myklebust } 1066944b0429STrond Myklebust 1067944b0429STrond Myklebust /** 1068944b0429STrond Myklebust * xprt_request_dequeue_transmit_locked - remove a task from the transmission queue 1069944b0429STrond Myklebust * @task: pointer to rpc_task 1070944b0429STrond Myklebust * 1071944b0429STrond Myklebust * Remove a task from the transmission queue 1072944b0429STrond Myklebust * Caller must hold xprt->queue_lock 1073944b0429STrond Myklebust */ 1074944b0429STrond Myklebust static void 1075944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(struct rpc_task *task) 1076944b0429STrond Myklebust { 1077944b0429STrond Myklebust if (test_and_clear_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 1078944b0429STrond Myklebust list_del(&task->tk_rqstp->rq_xmit); 1079944b0429STrond Myklebust } 1080944b0429STrond Myklebust 1081944b0429STrond Myklebust /** 1082944b0429STrond Myklebust * xprt_request_dequeue_transmit - remove a task from the transmission queue 1083944b0429STrond Myklebust * @task: pointer to rpc_task 1084944b0429STrond Myklebust * 1085944b0429STrond Myklebust * Remove a task from the transmission queue 1086944b0429STrond Myklebust */ 1087944b0429STrond Myklebust static void 1088944b0429STrond Myklebust xprt_request_dequeue_transmit(struct rpc_task *task) 1089944b0429STrond Myklebust { 1090944b0429STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1091944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1092944b0429STrond Myklebust 1093944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 1094944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1095944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1096944b0429STrond Myklebust } 1097944b0429STrond Myklebust 10987f3a1d1eSTrond Myklebust /** 1099762e4e67STrond Myklebust * xprt_request_need_retransmit - Test if a task needs retransmission 1100762e4e67STrond Myklebust * @task: pointer to rpc_task 1101762e4e67STrond Myklebust * 1102762e4e67STrond Myklebust * Test for whether a connection breakage requires the task to retransmit 1103762e4e67STrond Myklebust */ 1104762e4e67STrond Myklebust bool 1105762e4e67STrond Myklebust xprt_request_need_retransmit(struct rpc_task *task) 1106762e4e67STrond Myklebust { 1107762e4e67STrond Myklebust return xprt_request_retransmit_after_disconnect(task); 1108762e4e67STrond Myklebust } 1109762e4e67STrond Myklebust 1110762e4e67STrond Myklebust /** 11119903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 11129903cd1cSChuck Lever * @task: RPC task about to send a request 11139903cd1cSChuck Lever * 11141da177e4SLinus Torvalds */ 111590051ea7STrond Myklebust bool xprt_prepare_transmit(struct rpc_task *task) 11161da177e4SLinus Torvalds { 11171da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 11181da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 11191da177e4SLinus Torvalds 112046121cf7SChuck Lever dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); 11211da177e4SLinus Torvalds 11225f2f6bd9STrond Myklebust if (!xprt_lock_write(xprt, task)) { 11235f2f6bd9STrond Myklebust /* Race breaker: someone may have transmitted us */ 1124944b0429STrond Myklebust if (!test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 11255f2f6bd9STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, 11265f2f6bd9STrond Myklebust task, 0); 11275f2f6bd9STrond Myklebust return false; 11285f2f6bd9STrond Myklebust 11298a19a0b6STrond Myklebust } 11305f2f6bd9STrond Myklebust return true; 11311da177e4SLinus Torvalds } 11321da177e4SLinus Torvalds 1133e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 11345e5ce5beSTrond Myklebust { 1135343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 11365e5ce5beSTrond Myklebust } 11375e5ce5beSTrond Myklebust 11389903cd1cSChuck Lever /** 11399903cd1cSChuck Lever * xprt_transmit - send an RPC request on a transport 11409903cd1cSChuck Lever * @task: controlling RPC task 11419903cd1cSChuck Lever * 11429903cd1cSChuck Lever * We have to copy the iovec because sendmsg fiddles with its contents. 11439903cd1cSChuck Lever */ 11449903cd1cSChuck Lever void xprt_transmit(struct rpc_task *task) 11451da177e4SLinus Torvalds { 11461da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 11471da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 114890d91b0cSTrond Myklebust unsigned int connect_cookie; 1149dcbbeda8STrond Myklebust int is_retrans = RPC_WAS_SENT(task); 1150ff699ea8SChuck Lever int status; 11511da177e4SLinus Torvalds 115246121cf7SChuck Lever dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); 11531da177e4SLinus Torvalds 1154edc81dcdSTrond Myklebust if (!req->rq_bytes_sent) { 1155edc81dcdSTrond Myklebust if (xprt_request_data_received(task)) 1156944b0429STrond Myklebust goto out_dequeue; 11573021a5bbSTrond Myklebust /* Verify that our message lies in the RPCSEC_GSS window */ 1158edc81dcdSTrond Myklebust if (rpcauth_xmit_need_reencode(task)) { 11593021a5bbSTrond Myklebust task->tk_status = -EBADMSG; 1160944b0429STrond Myklebust goto out_dequeue; 11613021a5bbSTrond Myklebust } 11621da177e4SLinus Torvalds } 11631da177e4SLinus Torvalds 1164dcbbeda8STrond Myklebust /* 1165dcbbeda8STrond Myklebust * Update req->rq_ntrans before transmitting to avoid races with 1166dcbbeda8STrond Myklebust * xprt_update_rtt(), which needs to know that it is recording a 1167dcbbeda8STrond Myklebust * reply to the first transmission. 1168dcbbeda8STrond Myklebust */ 1169dcbbeda8STrond Myklebust req->rq_ntrans++; 1170dcbbeda8STrond Myklebust 117190d91b0cSTrond Myklebust connect_cookie = xprt->connect_cookie; 117250f484e2STrond Myklebust status = xprt->ops->send_request(req, task); 11733705ad64SJeff Layton trace_xprt_transmit(xprt, req->rq_xid, status); 1174c8485e4dSTrond Myklebust if (status != 0) { 1175dcbbeda8STrond Myklebust req->rq_ntrans--; 1176c8485e4dSTrond Myklebust task->tk_status = status; 1177c8485e4dSTrond Myklebust return; 1178c8485e4dSTrond Myklebust } 11797ebbbc6eSTrond Myklebust 1180dcbbeda8STrond Myklebust if (is_retrans) 1181dcbbeda8STrond Myklebust task->tk_client->cl_stats->rpcretrans++; 1182dcbbeda8STrond Myklebust 11834a068258SChuck Lever xprt_inject_disconnect(xprt); 1184c8485e4dSTrond Myklebust 118546121cf7SChuck Lever dprintk("RPC: %5u xmit complete\n", task->tk_pid); 1186468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 1187fe3aca29SChuck Lever spin_lock_bh(&xprt->transport_lock); 1188262ca07dSChuck Lever 1189262ca07dSChuck Lever xprt->stat.sends++; 1190262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 1191262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 119215a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 119315a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 1194fe3aca29SChuck Lever spin_unlock_bh(&xprt->transport_lock); 119590d91b0cSTrond Myklebust 119690d91b0cSTrond Myklebust req->rq_connect_cookie = connect_cookie; 1197944b0429STrond Myklebust out_dequeue: 1198944b0429STrond Myklebust xprt_request_dequeue_transmit(task); 11991da177e4SLinus Torvalds } 12001da177e4SLinus Torvalds 1201ba60eb25STrond Myklebust static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) 1202ba60eb25STrond Myklebust { 1203ba60eb25STrond Myklebust set_bit(XPRT_CONGESTED, &xprt->state); 1204ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1205ba60eb25STrond Myklebust } 1206ba60eb25STrond Myklebust 1207ba60eb25STrond Myklebust static void xprt_wake_up_backlog(struct rpc_xprt *xprt) 1208ba60eb25STrond Myklebust { 1209ba60eb25STrond Myklebust if (rpc_wake_up_next(&xprt->backlog) == NULL) 1210ba60eb25STrond Myklebust clear_bit(XPRT_CONGESTED, &xprt->state); 1211ba60eb25STrond Myklebust } 1212ba60eb25STrond Myklebust 1213ba60eb25STrond Myklebust static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) 1214ba60eb25STrond Myklebust { 1215ba60eb25STrond Myklebust bool ret = false; 1216ba60eb25STrond Myklebust 1217ba60eb25STrond Myklebust if (!test_bit(XPRT_CONGESTED, &xprt->state)) 1218ba60eb25STrond Myklebust goto out; 1219ba60eb25STrond Myklebust spin_lock(&xprt->reserve_lock); 1220ba60eb25STrond Myklebust if (test_bit(XPRT_CONGESTED, &xprt->state)) { 1221ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1222ba60eb25STrond Myklebust ret = true; 1223ba60eb25STrond Myklebust } 1224ba60eb25STrond Myklebust spin_unlock(&xprt->reserve_lock); 1225ba60eb25STrond Myklebust out: 1226ba60eb25STrond Myklebust return ret; 1227ba60eb25STrond Myklebust } 1228ba60eb25STrond Myklebust 122992ea011fSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt) 1230d9ba131dSTrond Myklebust { 1231d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 1232d9ba131dSTrond Myklebust 1233ff699ea8SChuck Lever if (xprt->num_reqs >= xprt->max_reqs) 1234d9ba131dSTrond Myklebust goto out; 1235ff699ea8SChuck Lever ++xprt->num_reqs; 123692ea011fSTrond Myklebust spin_unlock(&xprt->reserve_lock); 123792ea011fSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_NOFS); 123892ea011fSTrond Myklebust spin_lock(&xprt->reserve_lock); 1239d9ba131dSTrond Myklebust if (req != NULL) 1240d9ba131dSTrond Myklebust goto out; 1241ff699ea8SChuck Lever --xprt->num_reqs; 1242d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 1243d9ba131dSTrond Myklebust out: 1244d9ba131dSTrond Myklebust return req; 1245d9ba131dSTrond Myklebust } 1246d9ba131dSTrond Myklebust 1247d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1248d9ba131dSTrond Myklebust { 1249ff699ea8SChuck Lever if (xprt->num_reqs > xprt->min_reqs) { 1250ff699ea8SChuck Lever --xprt->num_reqs; 1251d9ba131dSTrond Myklebust kfree(req); 1252d9ba131dSTrond Myklebust return true; 1253d9ba131dSTrond Myklebust } 1254d9ba131dSTrond Myklebust return false; 1255d9ba131dSTrond Myklebust } 1256d9ba131dSTrond Myklebust 1257f39c1bfbSTrond Myklebust void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 12581da177e4SLinus Torvalds { 1259d9ba131dSTrond Myklebust struct rpc_rqst *req; 12601da177e4SLinus Torvalds 1261f39c1bfbSTrond Myklebust spin_lock(&xprt->reserve_lock); 12621da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 1263d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 1264d9ba131dSTrond Myklebust list_del(&req->rq_list); 1265d9ba131dSTrond Myklebust goto out_init_req; 1266d9ba131dSTrond Myklebust } 126792ea011fSTrond Myklebust req = xprt_dynamic_alloc_slot(xprt); 1268d9ba131dSTrond Myklebust if (!IS_ERR(req)) 1269d9ba131dSTrond Myklebust goto out_init_req; 1270d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 1271d9ba131dSTrond Myklebust case -ENOMEM: 1272d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 1273d9ba131dSTrond Myklebust "failed! Retrying\n"); 12741afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 1275d9ba131dSTrond Myklebust break; 1276d9ba131dSTrond Myklebust case -EAGAIN: 1277ba60eb25STrond Myklebust xprt_add_backlog(xprt, task); 1278d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 1279e9d47639SGustavo A. R. Silva /* fall through */ 12801afeaf5cSTrond Myklebust default: 1281d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 12821afeaf5cSTrond Myklebust } 1283f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 1284d9ba131dSTrond Myklebust return; 1285d9ba131dSTrond Myklebust out_init_req: 1286ff699ea8SChuck Lever xprt->stat.max_slots = max_t(unsigned int, xprt->stat.max_slots, 1287ff699ea8SChuck Lever xprt->num_reqs); 128837ac86c3SChuck Lever spin_unlock(&xprt->reserve_lock); 128937ac86c3SChuck Lever 1290d9ba131dSTrond Myklebust task->tk_status = 0; 12911da177e4SLinus Torvalds task->tk_rqstp = req; 12921da177e4SLinus Torvalds } 1293f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_alloc_slot); 1294f39c1bfbSTrond Myklebust 1295f39c1bfbSTrond Myklebust void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 1296f39c1bfbSTrond Myklebust { 1297f39c1bfbSTrond Myklebust /* Note: grabbing the xprt_lock_write() ensures that we throttle 1298f39c1bfbSTrond Myklebust * new slot allocation if the transport is congested (i.e. when 1299f39c1bfbSTrond Myklebust * reconnecting a stream transport or when out of socket write 1300f39c1bfbSTrond Myklebust * buffer space). 1301f39c1bfbSTrond Myklebust */ 1302f39c1bfbSTrond Myklebust if (xprt_lock_write(xprt, task)) { 1303f39c1bfbSTrond Myklebust xprt_alloc_slot(xprt, task); 1304f39c1bfbSTrond Myklebust xprt_release_write(xprt, task); 1305f39c1bfbSTrond Myklebust } 1306f39c1bfbSTrond Myklebust } 1307f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot); 13081da177e4SLinus Torvalds 1309a9cde23aSChuck Lever void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1310ee5ebe85STrond Myklebust { 1311ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1312c25573b5STrond Myklebust if (!xprt_dynamic_free_slot(xprt, req)) { 1313c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1314ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1315c25573b5STrond Myklebust } 1316ba60eb25STrond Myklebust xprt_wake_up_backlog(xprt); 1317ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1318ee5ebe85STrond Myklebust } 1319a9cde23aSChuck Lever EXPORT_SYMBOL_GPL(xprt_free_slot); 1320ee5ebe85STrond Myklebust 132121de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 132221de0a95STrond Myklebust { 132321de0a95STrond Myklebust struct rpc_rqst *req; 132421de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 132521de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 132621de0a95STrond Myklebust list_del(&req->rq_list); 132721de0a95STrond Myklebust kfree(req); 132821de0a95STrond Myklebust } 132921de0a95STrond Myklebust } 133021de0a95STrond Myklebust 1331d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1332d9ba131dSTrond Myklebust unsigned int num_prealloc, 1333d9ba131dSTrond Myklebust unsigned int max_alloc) 1334bd1722d4SPavel Emelyanov { 1335bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 133621de0a95STrond Myklebust struct rpc_rqst *req; 133721de0a95STrond Myklebust int i; 1338bd1722d4SPavel Emelyanov 1339bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1340bd1722d4SPavel Emelyanov if (xprt == NULL) 1341bd1722d4SPavel Emelyanov goto out; 1342bd1722d4SPavel Emelyanov 134321de0a95STrond Myklebust xprt_init(xprt, net); 134421de0a95STrond Myklebust 134521de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 134621de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 134721de0a95STrond Myklebust if (!req) 13488313164cSwangweidong goto out_free; 134921de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 135021de0a95STrond Myklebust } 1351d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1352d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1353d9ba131dSTrond Myklebust else 135421de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1355d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1356ff699ea8SChuck Lever xprt->num_reqs = num_prealloc; 1357bd1722d4SPavel Emelyanov 1358bd1722d4SPavel Emelyanov return xprt; 1359bd1722d4SPavel Emelyanov 1360bd1722d4SPavel Emelyanov out_free: 136121de0a95STrond Myklebust xprt_free(xprt); 1362bd1722d4SPavel Emelyanov out: 1363bd1722d4SPavel Emelyanov return NULL; 1364bd1722d4SPavel Emelyanov } 1365bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1366bd1722d4SPavel Emelyanov 1367e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1368e204e621SPavel Emelyanov { 136937aa2133SPavel Emelyanov put_net(xprt->xprt_net); 137021de0a95STrond Myklebust xprt_free_all_slots(xprt); 1371fda1bfefSTrond Myklebust kfree_rcu(xprt, rcu); 1372e204e621SPavel Emelyanov } 1373e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1374e204e621SPavel Emelyanov 1375902c5887STrond Myklebust static void 1376902c5887STrond Myklebust xprt_init_connect_cookie(struct rpc_rqst *req, struct rpc_xprt *xprt) 1377902c5887STrond Myklebust { 1378902c5887STrond Myklebust req->rq_connect_cookie = xprt_connect_cookie(xprt) - 1; 1379902c5887STrond Myklebust } 1380902c5887STrond Myklebust 13819dc6edcfSTrond Myklebust static __be32 13829dc6edcfSTrond Myklebust xprt_alloc_xid(struct rpc_xprt *xprt) 13839dc6edcfSTrond Myklebust { 13849dc6edcfSTrond Myklebust __be32 xid; 13859dc6edcfSTrond Myklebust 13869dc6edcfSTrond Myklebust spin_lock(&xprt->reserve_lock); 13879dc6edcfSTrond Myklebust xid = (__force __be32)xprt->xid++; 13889dc6edcfSTrond Myklebust spin_unlock(&xprt->reserve_lock); 13899dc6edcfSTrond Myklebust return xid; 13909dc6edcfSTrond Myklebust } 13919dc6edcfSTrond Myklebust 13929dc6edcfSTrond Myklebust static void 13939dc6edcfSTrond Myklebust xprt_init_xid(struct rpc_xprt *xprt) 13949dc6edcfSTrond Myklebust { 13959dc6edcfSTrond Myklebust xprt->xid = prandom_u32(); 13969dc6edcfSTrond Myklebust } 13979dc6edcfSTrond Myklebust 13989dc6edcfSTrond Myklebust static void 13999dc6edcfSTrond Myklebust xprt_request_init(struct rpc_task *task) 14009dc6edcfSTrond Myklebust { 14019dc6edcfSTrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 14029dc6edcfSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 14039dc6edcfSTrond Myklebust 14049dc6edcfSTrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 14059dc6edcfSTrond Myklebust req->rq_task = task; 14069dc6edcfSTrond Myklebust req->rq_xprt = xprt; 14079dc6edcfSTrond Myklebust req->rq_buffer = NULL; 14089dc6edcfSTrond Myklebust req->rq_xid = xprt_alloc_xid(xprt); 1409902c5887STrond Myklebust xprt_init_connect_cookie(req, xprt); 14109dc6edcfSTrond Myklebust req->rq_bytes_sent = 0; 14119dc6edcfSTrond Myklebust req->rq_snd_buf.len = 0; 14129dc6edcfSTrond Myklebust req->rq_snd_buf.buflen = 0; 14139dc6edcfSTrond Myklebust req->rq_rcv_buf.len = 0; 14149dc6edcfSTrond Myklebust req->rq_rcv_buf.buflen = 0; 14159dc6edcfSTrond Myklebust req->rq_release_snd_buf = NULL; 14169dc6edcfSTrond Myklebust xprt_reset_majortimeo(req); 14179dc6edcfSTrond Myklebust dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, 14189dc6edcfSTrond Myklebust req, ntohl(req->rq_xid)); 14199dc6edcfSTrond Myklebust } 14209dc6edcfSTrond Myklebust 14219dc6edcfSTrond Myklebust static void 14229dc6edcfSTrond Myklebust xprt_do_reserve(struct rpc_xprt *xprt, struct rpc_task *task) 14239dc6edcfSTrond Myklebust { 14249dc6edcfSTrond Myklebust xprt->ops->alloc_slot(xprt, task); 14259dc6edcfSTrond Myklebust if (task->tk_rqstp != NULL) 14269dc6edcfSTrond Myklebust xprt_request_init(task); 14279dc6edcfSTrond Myklebust } 14289dc6edcfSTrond Myklebust 14299903cd1cSChuck Lever /** 14309903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 14319903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 14329903cd1cSChuck Lever * 1433ba60eb25STrond Myklebust * If the transport is marked as being congested, or if no more 1434ba60eb25STrond Myklebust * slots are available, place the task on the transport's 14359903cd1cSChuck Lever * backlog queue. 14369903cd1cSChuck Lever */ 14379903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 14381da177e4SLinus Torvalds { 1439fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 14401da177e4SLinus Torvalds 144143cedbf0STrond Myklebust task->tk_status = 0; 144243cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 144343cedbf0STrond Myklebust return; 144443cedbf0STrond Myklebust 144543cedbf0STrond Myklebust task->tk_timeout = 0; 144643cedbf0STrond Myklebust task->tk_status = -EAGAIN; 1447ba60eb25STrond Myklebust if (!xprt_throttle_congested(xprt, task)) 14489dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 1449ba60eb25STrond Myklebust } 1450ba60eb25STrond Myklebust 1451ba60eb25STrond Myklebust /** 1452ba60eb25STrond Myklebust * xprt_retry_reserve - allocate an RPC request slot 1453ba60eb25STrond Myklebust * @task: RPC task requesting a slot allocation 1454ba60eb25STrond Myklebust * 1455ba60eb25STrond Myklebust * If no more slots are available, place the task on the transport's 1456ba60eb25STrond Myklebust * backlog queue. 1457ba60eb25STrond Myklebust * Note that the only difference with xprt_reserve is that we now 1458ba60eb25STrond Myklebust * ignore the value of the XPRT_CONGESTED flag. 1459ba60eb25STrond Myklebust */ 1460ba60eb25STrond Myklebust void xprt_retry_reserve(struct rpc_task *task) 1461ba60eb25STrond Myklebust { 1462fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 1463ba60eb25STrond Myklebust 1464ba60eb25STrond Myklebust task->tk_status = 0; 1465ba60eb25STrond Myklebust if (task->tk_rqstp != NULL) 1466ba60eb25STrond Myklebust return; 1467ba60eb25STrond Myklebust 1468ba60eb25STrond Myklebust task->tk_timeout = 0; 1469ba60eb25STrond Myklebust task->tk_status = -EAGAIN; 14709dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 14711da177e4SLinus Torvalds } 14721da177e4SLinus Torvalds 1473edc81dcdSTrond Myklebust static void 1474edc81dcdSTrond Myklebust xprt_request_dequeue_all(struct rpc_task *task, struct rpc_rqst *req) 1475edc81dcdSTrond Myklebust { 1476edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1477edc81dcdSTrond Myklebust 1478944b0429STrond Myklebust if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) || 1479944b0429STrond Myklebust test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || 1480edc81dcdSTrond Myklebust xprt_is_pinned_rqst(req)) { 1481edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1482944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1483edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 1484edc81dcdSTrond Myklebust while (xprt_is_pinned_rqst(req)) { 1485edc81dcdSTrond Myklebust set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1486edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1487edc81dcdSTrond Myklebust xprt_wait_on_pinned_rqst(req); 1488edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1489edc81dcdSTrond Myklebust clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1490edc81dcdSTrond Myklebust } 1491edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1492edc81dcdSTrond Myklebust } 1493edc81dcdSTrond Myklebust } 1494edc81dcdSTrond Myklebust 14959903cd1cSChuck Lever /** 14969903cd1cSChuck Lever * xprt_release - release an RPC request slot 14979903cd1cSChuck Lever * @task: task which is finished with the slot 14989903cd1cSChuck Lever * 14991da177e4SLinus Torvalds */ 15009903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 15011da177e4SLinus Torvalds { 150255ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 150387ed5003STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 15041da177e4SLinus Torvalds 150587ed5003STrond Myklebust if (req == NULL) { 150687ed5003STrond Myklebust if (task->tk_client) { 1507fb43d172STrond Myklebust xprt = task->tk_xprt; 150887ed5003STrond Myklebust if (xprt->snd_task == task) 150987ed5003STrond Myklebust xprt_release_write(xprt, task); 151087ed5003STrond Myklebust } 15111da177e4SLinus Torvalds return; 151287ed5003STrond Myklebust } 151355ae1aabSRicardo Labiaga 151455ae1aabSRicardo Labiaga xprt = req->rq_xprt; 15150a702195SWeston Andros Adamson if (task->tk_ops->rpc_count_stats != NULL) 15160a702195SWeston Andros Adamson task->tk_ops->rpc_count_stats(task, task->tk_calldata); 15170a702195SWeston Andros Adamson else if (task->tk_client) 15180a702195SWeston Andros Adamson rpc_count_iostats(task, task->tk_client->cl_metrics); 1519edc81dcdSTrond Myklebust xprt_request_dequeue_all(task, req); 15204a0f8c04SChuck Lever spin_lock_bh(&xprt->transport_lock); 152149e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1522a58dd398SChuck Lever if (xprt->ops->release_request) 1523a58dd398SChuck Lever xprt->ops->release_request(task); 15241da177e4SLinus Torvalds xprt->last_used = jiffies; 1525ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 15264a0f8c04SChuck Lever spin_unlock_bh(&xprt->transport_lock); 1527ee5ebe85STrond Myklebust if (req->rq_buffer) 15283435c74aSChuck Lever xprt->ops->buf_free(task); 15294a068258SChuck Lever xprt_inject_disconnect(xprt); 1530a17c2153STrond Myklebust if (req->rq_cred != NULL) 1531a17c2153STrond Myklebust put_rpccred(req->rq_cred); 15321da177e4SLinus Torvalds task->tk_rqstp = NULL; 1533ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1534ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 153555ae1aabSRicardo Labiaga 153646121cf7SChuck Lever dprintk("RPC: %5u release request %p\n", task->tk_pid, req); 1537ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1538a9cde23aSChuck Lever xprt->ops->free_slot(xprt, req); 1539ee5ebe85STrond Myklebust else 1540c9acb42eSTrond Myklebust xprt_free_bc_request(req); 15411da177e4SLinus Torvalds } 15421da177e4SLinus Torvalds 1543902c5887STrond Myklebust #ifdef CONFIG_SUNRPC_BACKCHANNEL 1544902c5887STrond Myklebust void 1545902c5887STrond Myklebust xprt_init_bc_request(struct rpc_rqst *req, struct rpc_task *task) 1546902c5887STrond Myklebust { 1547902c5887STrond Myklebust struct xdr_buf *xbufp = &req->rq_snd_buf; 1548902c5887STrond Myklebust 1549902c5887STrond Myklebust task->tk_rqstp = req; 1550902c5887STrond Myklebust req->rq_task = task; 1551902c5887STrond Myklebust xprt_init_connect_cookie(req, req->rq_xprt); 1552902c5887STrond Myklebust /* 1553902c5887STrond Myklebust * Set up the xdr_buf length. 1554902c5887STrond Myklebust * This also indicates that the buffer is XDR encoded already. 1555902c5887STrond Myklebust */ 1556902c5887STrond Myklebust xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1557902c5887STrond Myklebust xbufp->tail[0].iov_len; 1558902c5887STrond Myklebust req->rq_bytes_sent = 0; 1559902c5887STrond Myklebust } 1560902c5887STrond Myklebust #endif 1561902c5887STrond Myklebust 156221de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1563c2866763SChuck Lever { 156430c5116bSTrond Myklebust kref_init(&xprt->kref); 1565c2866763SChuck Lever 1566c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1567c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 156875c84151STrond Myklebust spin_lock_init(&xprt->queue_lock); 1569c2866763SChuck Lever 1570c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 1571ef3f5434STrond Myklebust INIT_LIST_HEAD(&xprt->recv_queue); 1572944b0429STrond Myklebust INIT_LIST_HEAD(&xprt->xmit_queue); 15739e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1574f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1575f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 15769e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 157780b14d5eSTrond Myklebust INIT_LIST_HEAD(&xprt->xprt_switch); 1578f9acac1aSRicardo Labiaga 1579c2866763SChuck Lever xprt->last_used = jiffies; 1580c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1581a509050bSChuck Lever xprt->bind_index = 0; 1582c2866763SChuck Lever 1583c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1584c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 158534006ceeSTrond Myklebust rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); 1586c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1587c2866763SChuck Lever 1588c2866763SChuck Lever xprt_init_xid(xprt); 1589c2866763SChuck Lever 159021de0a95STrond Myklebust xprt->xprt_net = get_net(net); 15918d9266ffSTrond Myklebust } 15928d9266ffSTrond Myklebust 15938d9266ffSTrond Myklebust /** 15948d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 15958d9266ffSTrond Myklebust * @args: rpc transport creation arguments 15968d9266ffSTrond Myklebust * 15978d9266ffSTrond Myklebust */ 15988d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 15998d9266ffSTrond Myklebust { 16008d9266ffSTrond Myklebust struct rpc_xprt *xprt; 16018d9266ffSTrond Myklebust struct xprt_class *t; 16028d9266ffSTrond Myklebust 16038d9266ffSTrond Myklebust spin_lock(&xprt_list_lock); 16048d9266ffSTrond Myklebust list_for_each_entry(t, &xprt_list, list) { 16058d9266ffSTrond Myklebust if (t->ident == args->ident) { 16068d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 16078d9266ffSTrond Myklebust goto found; 16088d9266ffSTrond Myklebust } 16098d9266ffSTrond Myklebust } 16108d9266ffSTrond Myklebust spin_unlock(&xprt_list_lock); 16113c45ddf8SChuck Lever dprintk("RPC: transport (%d) not supported\n", args->ident); 16128d9266ffSTrond Myklebust return ERR_PTR(-EIO); 16138d9266ffSTrond Myklebust 16148d9266ffSTrond Myklebust found: 16158d9266ffSTrond Myklebust xprt = t->setup(args); 16168d9266ffSTrond Myklebust if (IS_ERR(xprt)) { 16178d9266ffSTrond Myklebust dprintk("RPC: xprt_create_transport: failed, %ld\n", 16188d9266ffSTrond Myklebust -PTR_ERR(xprt)); 161921de0a95STrond Myklebust goto out; 16208d9266ffSTrond Myklebust } 162133d90ac0SJ. Bruce Fields if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) 162233d90ac0SJ. Bruce Fields xprt->idle_timeout = 0; 162321de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 162421de0a95STrond Myklebust if (xprt_has_timer(xprt)) 1625ff861c4dSKees Cook timer_setup(&xprt->timer, xprt_init_autodisconnect, 0); 162621de0a95STrond Myklebust else 1627ff861c4dSKees Cook timer_setup(&xprt->timer, NULL, 0); 16284e0038b6STrond Myklebust 16294e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 16304e0038b6STrond Myklebust xprt_destroy(xprt); 16314e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 16324e0038b6STrond Myklebust } 16334e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 16344e0038b6STrond Myklebust if (xprt->servername == NULL) { 16354e0038b6STrond Myklebust xprt_destroy(xprt); 16364e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 16374e0038b6STrond Myklebust } 16384e0038b6STrond Myklebust 16393f940098SJeff Layton rpc_xprt_debugfs_register(xprt); 1640388f0c77SJeff Layton 1641c2866763SChuck Lever dprintk("RPC: created transport %p with %u slots\n", xprt, 1642c2866763SChuck Lever xprt->max_reqs); 164321de0a95STrond Myklebust out: 1644c2866763SChuck Lever return xprt; 1645c2866763SChuck Lever } 1646c2866763SChuck Lever 1647528fd354STrond Myklebust static void xprt_destroy_cb(struct work_struct *work) 1648528fd354STrond Myklebust { 1649528fd354STrond Myklebust struct rpc_xprt *xprt = 1650528fd354STrond Myklebust container_of(work, struct rpc_xprt, task_cleanup); 1651528fd354STrond Myklebust 1652528fd354STrond Myklebust rpc_xprt_debugfs_unregister(xprt); 1653528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 1654528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 1655528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 1656528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 1657528fd354STrond Myklebust kfree(xprt->servername); 1658528fd354STrond Myklebust /* 1659528fd354STrond Myklebust * Tear down transport state and free the rpc_xprt 1660528fd354STrond Myklebust */ 1661528fd354STrond Myklebust xprt->ops->destroy(xprt); 1662528fd354STrond Myklebust } 1663528fd354STrond Myklebust 16649903cd1cSChuck Lever /** 16659903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 1666a8de240aSTrond Myklebust * @xprt: transport to destroy 16679903cd1cSChuck Lever * 16681da177e4SLinus Torvalds */ 1669a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 16701da177e4SLinus Torvalds { 16711da177e4SLinus Torvalds dprintk("RPC: destroying transport %p\n", xprt); 167279234c3dSTrond Myklebust 1673528fd354STrond Myklebust /* 1674528fd354STrond Myklebust * Exclude transport connect/disconnect handlers and autoclose 1675528fd354STrond Myklebust */ 167679234c3dSTrond Myklebust wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); 167779234c3dSTrond Myklebust 16780065db32STrond Myklebust del_timer_sync(&xprt->timer); 1679c8541ecdSChuck Lever 1680c8541ecdSChuck Lever /* 1681528fd354STrond Myklebust * Destroy sockets etc from the system workqueue so they can 1682528fd354STrond Myklebust * safely flush receive work running on rpciod. 1683c8541ecdSChuck Lever */ 1684528fd354STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_destroy_cb); 1685528fd354STrond Myklebust schedule_work(&xprt->task_cleanup); 16866b6ca86bSTrond Myklebust } 16871da177e4SLinus Torvalds 168830c5116bSTrond Myklebust static void xprt_destroy_kref(struct kref *kref) 168930c5116bSTrond Myklebust { 169030c5116bSTrond Myklebust xprt_destroy(container_of(kref, struct rpc_xprt, kref)); 169130c5116bSTrond Myklebust } 169230c5116bSTrond Myklebust 169330c5116bSTrond Myklebust /** 169430c5116bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 169530c5116bSTrond Myklebust * @xprt: pointer to the transport 169630c5116bSTrond Myklebust * 169730c5116bSTrond Myklebust */ 169830c5116bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 169930c5116bSTrond Myklebust { 170030c5116bSTrond Myklebust if (xprt != NULL && kref_get_unless_zero(&xprt->kref)) 170130c5116bSTrond Myklebust return xprt; 170230c5116bSTrond Myklebust return NULL; 170330c5116bSTrond Myklebust } 170430c5116bSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_get); 170530c5116bSTrond Myklebust 17066b6ca86bSTrond Myklebust /** 17076b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 17086b6ca86bSTrond Myklebust * @xprt: pointer to the transport 17096b6ca86bSTrond Myklebust * 17106b6ca86bSTrond Myklebust */ 17116b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 17126b6ca86bSTrond Myklebust { 171330c5116bSTrond Myklebust if (xprt != NULL) 171430c5116bSTrond Myklebust kref_put(&xprt->kref, xprt_destroy_kref); 17156b6ca86bSTrond Myklebust } 17165d252f90SChuck Lever EXPORT_SYMBOL_GPL(xprt_put); 1717