1457c8996SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * linux/net/sunrpc/xprt.c 41da177e4SLinus Torvalds * 51da177e4SLinus Torvalds * This is a generic RPC call interface supporting congestion avoidance, 61da177e4SLinus Torvalds * and asynchronous calls. 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * The interface works like this: 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * - When a process places a call, it allocates a request slot if 111da177e4SLinus Torvalds * one is available. Otherwise, it sleeps on the backlog queue 121da177e4SLinus Torvalds * (xprt_reserve). 131da177e4SLinus Torvalds * - Next, the caller puts together the RPC message, stuffs it into 1455aa4f58SChuck Lever * the request struct, and calls xprt_transmit(). 1555aa4f58SChuck Lever * - xprt_transmit sends the message and installs the caller on the 1655ae1aabSRicardo Labiaga * transport's wait list. At the same time, if a reply is expected, 1755ae1aabSRicardo Labiaga * it installs a timer that is run after the packet's timeout has 1855ae1aabSRicardo Labiaga * expired. 191da177e4SLinus Torvalds * - When a packet arrives, the data_ready handler walks the list of 2055aa4f58SChuck Lever * pending requests for that transport. If a matching XID is found, the 211da177e4SLinus Torvalds * caller is woken up, and the timer removed. 221da177e4SLinus Torvalds * - When no reply arrives within the timeout interval, the timer is 231da177e4SLinus Torvalds * fired by the kernel and runs xprt_timer(). It either adjusts the 241da177e4SLinus Torvalds * timeout values (minor timeout) or wakes up the caller with a status 251da177e4SLinus Torvalds * of -ETIMEDOUT. 261da177e4SLinus Torvalds * - When the caller receives a notification from RPC that a reply arrived, 271da177e4SLinus Torvalds * it should release the RPC slot, and process the reply. 281da177e4SLinus Torvalds * If the call timed out, it may choose to retry the operation by 291da177e4SLinus Torvalds * adjusting the initial timeout value, and simply calling rpc_call 301da177e4SLinus Torvalds * again. 311da177e4SLinus Torvalds * 321da177e4SLinus Torvalds * Support for async RPC is done through a set of RPC-specific scheduling 331da177e4SLinus Torvalds * primitives that `transparently' work for processes as well as async 341da177e4SLinus Torvalds * tasks that rely on callbacks. 351da177e4SLinus Torvalds * 361da177e4SLinus Torvalds * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> 3755aa4f58SChuck Lever * 3855aa4f58SChuck Lever * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> 391da177e4SLinus Torvalds */ 401da177e4SLinus Torvalds 41a246b010SChuck Lever #include <linux/module.h> 42a246b010SChuck Lever 431da177e4SLinus Torvalds #include <linux/types.h> 44a246b010SChuck Lever #include <linux/interrupt.h> 451da177e4SLinus Torvalds #include <linux/workqueue.h> 46bf3fcf89SChuck Lever #include <linux/net.h> 47ff839970SChuck Lever #include <linux/ktime.h> 481da177e4SLinus Torvalds 49a246b010SChuck Lever #include <linux/sunrpc/clnt.h> 5011c556b3SChuck Lever #include <linux/sunrpc/metrics.h> 51c9acb42eSTrond Myklebust #include <linux/sunrpc/bc_xprt.h> 52fda1bfefSTrond Myklebust #include <linux/rcupdate.h> 53a1231fdaSTrond Myklebust #include <linux/sched/mm.h> 541da177e4SLinus Torvalds 553705ad64SJeff Layton #include <trace/events/sunrpc.h> 563705ad64SJeff Layton 5755ae1aabSRicardo Labiaga #include "sunrpc.h" 5855ae1aabSRicardo Labiaga 591da177e4SLinus Torvalds /* 601da177e4SLinus Torvalds * Local variables 611da177e4SLinus Torvalds */ 621da177e4SLinus Torvalds 63f895b252SJeff Layton #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 641da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 651da177e4SLinus Torvalds #endif 661da177e4SLinus Torvalds 671da177e4SLinus Torvalds /* 681da177e4SLinus Torvalds * Local functions 691da177e4SLinus Torvalds */ 7021de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 7137ac86c3SChuck Lever static __be32 xprt_alloc_xid(struct rpc_xprt *xprt); 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\ 779e910bffSTrond Myklebust static unsigned long xprt_request_timeout(const struct rpc_rqst *req) 789e910bffSTrond Myklebust { 799e910bffSTrond Myklebust unsigned long timeout = jiffies + req->rq_timeout; 809e910bffSTrond Myklebust 819e910bffSTrond Myklebust if (time_before(timeout, req->rq_majortimeo)) 829e910bffSTrond Myklebust return timeout; 839e910bffSTrond Myklebust return req->rq_majortimeo; 849e910bffSTrond Myklebust } 859e910bffSTrond Myklebust 8612a80469SChuck Lever /** 8781c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 8881c098afS\"Talpey, Thomas\ * @transport: transport to register 8981c098afS\"Talpey, Thomas\ * 9081c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 9181c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 9281c098afS\"Talpey, Thomas\ * 9381c098afS\"Talpey, Thomas\ * Returns: 9481c098afS\"Talpey, Thomas\ * 0: transport successfully registered 9581c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 9681c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 9781c098afS\"Talpey, Thomas\ */ 9881c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 9981c098afS\"Talpey, Thomas\ { 10081c098afS\"Talpey, Thomas\ struct xprt_class *t; 10181c098afS\"Talpey, Thomas\ int result; 10281c098afS\"Talpey, Thomas\ 10381c098afS\"Talpey, Thomas\ result = -EEXIST; 10481c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 10581c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 10681c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 1074fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 10881c098afS\"Talpey, Thomas\ goto out; 10981c098afS\"Talpey, Thomas\ } 11081c098afS\"Talpey, Thomas\ 11181c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 11281c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 11381c098afS\"Talpey, Thomas\ transport->name); 11481c098afS\"Talpey, Thomas\ result = 0; 11581c098afS\"Talpey, Thomas\ 11681c098afS\"Talpey, Thomas\ out: 11781c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 11881c098afS\"Talpey, Thomas\ return result; 11981c098afS\"Talpey, Thomas\ } 12081c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 12181c098afS\"Talpey, Thomas\ 12281c098afS\"Talpey, Thomas\ /** 12381c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 12465b6e42cSRandy Dunlap * @transport: transport to unregister 12581c098afS\"Talpey, Thomas\ * 12681c098afS\"Talpey, Thomas\ * Returns: 12781c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 12881c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 12981c098afS\"Talpey, Thomas\ */ 13081c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 13181c098afS\"Talpey, Thomas\ { 13281c098afS\"Talpey, Thomas\ struct xprt_class *t; 13381c098afS\"Talpey, Thomas\ int result; 13481c098afS\"Talpey, Thomas\ 13581c098afS\"Talpey, Thomas\ result = 0; 13681c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 13781c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 13881c098afS\"Talpey, Thomas\ if (t == transport) { 13981c098afS\"Talpey, Thomas\ printk(KERN_INFO 14081c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 14181c098afS\"Talpey, Thomas\ transport->name); 14281c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 14381c098afS\"Talpey, Thomas\ goto out; 14481c098afS\"Talpey, Thomas\ } 14581c098afS\"Talpey, Thomas\ } 14681c098afS\"Talpey, Thomas\ result = -ENOENT; 14781c098afS\"Talpey, Thomas\ 14881c098afS\"Talpey, Thomas\ out: 14981c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 15081c098afS\"Talpey, Thomas\ return result; 15181c098afS\"Talpey, Thomas\ } 15281c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 15381c098afS\"Talpey, Thomas\ 154d5aa6b22STrond Myklebust static void 155d5aa6b22STrond Myklebust xprt_class_release(const struct xprt_class *t) 156d5aa6b22STrond Myklebust { 157d5aa6b22STrond Myklebust module_put(t->owner); 158d5aa6b22STrond Myklebust } 159d5aa6b22STrond Myklebust 160d5aa6b22STrond Myklebust static const struct xprt_class * 1619bccd264STrond Myklebust xprt_class_find_by_ident_locked(int ident) 1629bccd264STrond Myklebust { 1639bccd264STrond Myklebust const struct xprt_class *t; 1649bccd264STrond Myklebust 1659bccd264STrond Myklebust list_for_each_entry(t, &xprt_list, list) { 1669bccd264STrond Myklebust if (t->ident != ident) 1679bccd264STrond Myklebust continue; 1689bccd264STrond Myklebust if (!try_module_get(t->owner)) 1699bccd264STrond Myklebust continue; 1709bccd264STrond Myklebust return t; 1719bccd264STrond Myklebust } 1729bccd264STrond Myklebust return NULL; 1739bccd264STrond Myklebust } 1749bccd264STrond Myklebust 1759bccd264STrond Myklebust static const struct xprt_class * 1769bccd264STrond Myklebust xprt_class_find_by_ident(int ident) 1779bccd264STrond Myklebust { 1789bccd264STrond Myklebust const struct xprt_class *t; 1799bccd264STrond Myklebust 1809bccd264STrond Myklebust spin_lock(&xprt_list_lock); 1819bccd264STrond Myklebust t = xprt_class_find_by_ident_locked(ident); 1829bccd264STrond Myklebust spin_unlock(&xprt_list_lock); 1839bccd264STrond Myklebust return t; 1849bccd264STrond Myklebust } 1859bccd264STrond Myklebust 1869bccd264STrond Myklebust static const struct xprt_class * 187d5aa6b22STrond Myklebust xprt_class_find_by_netid_locked(const char *netid) 188d5aa6b22STrond Myklebust { 189d5aa6b22STrond Myklebust const struct xprt_class *t; 190d5aa6b22STrond Myklebust unsigned int i; 191d5aa6b22STrond Myklebust 192d5aa6b22STrond Myklebust list_for_each_entry(t, &xprt_list, list) { 193d5aa6b22STrond Myklebust for (i = 0; t->netid[i][0] != '\0'; i++) { 194d5aa6b22STrond Myklebust if (strcmp(t->netid[i], netid) != 0) 195d5aa6b22STrond Myklebust continue; 196d5aa6b22STrond Myklebust if (!try_module_get(t->owner)) 197d5aa6b22STrond Myklebust continue; 198d5aa6b22STrond Myklebust return t; 199d5aa6b22STrond Myklebust } 200d5aa6b22STrond Myklebust } 201d5aa6b22STrond Myklebust return NULL; 202d5aa6b22STrond Myklebust } 203d5aa6b22STrond Myklebust 204d5aa6b22STrond Myklebust static const struct xprt_class * 205d5aa6b22STrond Myklebust xprt_class_find_by_netid(const char *netid) 206d5aa6b22STrond Myklebust { 207d5aa6b22STrond Myklebust const struct xprt_class *t; 208d5aa6b22STrond Myklebust 209d5aa6b22STrond Myklebust spin_lock(&xprt_list_lock); 210d5aa6b22STrond Myklebust t = xprt_class_find_by_netid_locked(netid); 211d5aa6b22STrond Myklebust if (!t) { 212d5aa6b22STrond Myklebust spin_unlock(&xprt_list_lock); 213d5aa6b22STrond Myklebust request_module("rpc%s", netid); 214d5aa6b22STrond Myklebust spin_lock(&xprt_list_lock); 215d5aa6b22STrond Myklebust t = xprt_class_find_by_netid_locked(netid); 216d5aa6b22STrond Myklebust } 217d5aa6b22STrond Myklebust spin_unlock(&xprt_list_lock); 218d5aa6b22STrond Myklebust return t; 219d5aa6b22STrond Myklebust } 220d5aa6b22STrond Myklebust 22181c098afS\"Talpey, Thomas\ /** 222*1fc5f131STrond Myklebust * xprt_find_transport_ident - convert a netid into a transport identifier 223*1fc5f131STrond Myklebust * @netid: transport to load 224*1fc5f131STrond Myklebust * 225*1fc5f131STrond Myklebust * Returns: 226*1fc5f131STrond Myklebust * > 0: transport identifier 227*1fc5f131STrond Myklebust * -ENOENT: transport module not available 228*1fc5f131STrond Myklebust */ 229*1fc5f131STrond Myklebust int xprt_find_transport_ident(const char *netid) 230*1fc5f131STrond Myklebust { 231*1fc5f131STrond Myklebust const struct xprt_class *t; 232*1fc5f131STrond Myklebust int ret; 233*1fc5f131STrond Myklebust 234*1fc5f131STrond Myklebust t = xprt_class_find_by_netid(netid); 235*1fc5f131STrond Myklebust if (!t) 236*1fc5f131STrond Myklebust return -ENOENT; 237*1fc5f131STrond Myklebust ret = t->ident; 238*1fc5f131STrond Myklebust xprt_class_release(t); 239*1fc5f131STrond Myklebust return ret; 240*1fc5f131STrond Myklebust } 241*1fc5f131STrond Myklebust EXPORT_SYMBOL_GPL(xprt_find_transport_ident); 242*1fc5f131STrond Myklebust 243*1fc5f131STrond Myklebust /** 244441e3e24STom Talpey * xprt_load_transport - load a transport implementation 245d5aa6b22STrond Myklebust * @netid: transport to load 246441e3e24STom Talpey * 247441e3e24STom Talpey * Returns: 248441e3e24STom Talpey * 0: transport successfully loaded 249441e3e24STom Talpey * -ENOENT: transport module not available 250441e3e24STom Talpey */ 251d5aa6b22STrond Myklebust int xprt_load_transport(const char *netid) 252441e3e24STom Talpey { 253*1fc5f131STrond Myklebust int ret = xprt_find_transport_ident(netid); 254*1fc5f131STrond Myklebust return ret < 0 ? ret : 0; 255441e3e24STom Talpey } 256441e3e24STom Talpey EXPORT_SYMBOL_GPL(xprt_load_transport); 257441e3e24STom Talpey 258c544577dSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 259c544577dSTrond Myklebust { 260c544577dSTrond Myklebust xprt->snd_task = NULL; 261c544577dSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 262c544577dSTrond Myklebust smp_mb__before_atomic(); 263c544577dSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 264c544577dSTrond Myklebust smp_mb__after_atomic(); 265c544577dSTrond Myklebust } else 266c544577dSTrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 267c544577dSTrond Myklebust } 268c544577dSTrond Myklebust 269441e3e24STom Talpey /** 27012a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 27112a80469SChuck Lever * @task: task that is requesting access to the transport 272177c27bfSRandy Dunlap * @xprt: pointer to the target transport 27312a80469SChuck Lever * 27412a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 27512a80469SChuck Lever * transport connects from colliding with writes. No congestion control 27612a80469SChuck Lever * is provided. 2771da177e4SLinus Torvalds */ 27843cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 2791da177e4SLinus Torvalds { 28012a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 28112a80469SChuck Lever 28212a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 28312a80469SChuck Lever if (task == xprt->snd_task) 284bf7ca707SChuck Lever goto out_locked; 28512a80469SChuck Lever goto out_sleep; 28612a80469SChuck Lever } 287c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 288c544577dSTrond Myklebust goto out_unlock; 28912a80469SChuck Lever xprt->snd_task = task; 2904d4a76f3Sj223yang@asset.uwaterloo.ca 291bf7ca707SChuck Lever out_locked: 292bf7ca707SChuck Lever trace_xprt_reserve_xprt(xprt, task); 29312a80469SChuck Lever return 1; 29412a80469SChuck Lever 295c544577dSTrond Myklebust out_unlock: 296c544577dSTrond Myklebust xprt_clear_locked(xprt); 29712a80469SChuck Lever out_sleep: 29812a80469SChuck Lever task->tk_status = -EAGAIN; 2996b2e6856STrond Myklebust if (RPC_IS_SOFT(task)) 3006b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->sending, task, NULL, 3019e910bffSTrond Myklebust xprt_request_timeout(req)); 3026b2e6856STrond Myklebust else 30379c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 30412a80469SChuck Lever return 0; 30512a80469SChuck Lever } 30612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 30712a80469SChuck Lever 30875891f50STrond Myklebust static bool 30975891f50STrond Myklebust xprt_need_congestion_window_wait(struct rpc_xprt *xprt) 31075891f50STrond Myklebust { 31175891f50STrond Myklebust return test_bit(XPRT_CWND_WAIT, &xprt->state); 31275891f50STrond Myklebust } 31375891f50STrond Myklebust 31475891f50STrond Myklebust static void 31575891f50STrond Myklebust xprt_set_congestion_window_wait(struct rpc_xprt *xprt) 31675891f50STrond Myklebust { 31775891f50STrond Myklebust if (!list_empty(&xprt->xmit_queue)) { 31875891f50STrond Myklebust /* Peek at head of queue to see if it can make progress */ 31975891f50STrond Myklebust if (list_first_entry(&xprt->xmit_queue, struct rpc_rqst, 32075891f50STrond Myklebust rq_xmit)->rq_cong) 32175891f50STrond Myklebust return; 32275891f50STrond Myklebust } 32375891f50STrond Myklebust set_bit(XPRT_CWND_WAIT, &xprt->state); 32475891f50STrond Myklebust } 32575891f50STrond Myklebust 32675891f50STrond Myklebust static void 32775891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(struct rpc_xprt *xprt) 32875891f50STrond Myklebust { 32975891f50STrond Myklebust if (!RPCXPRT_CONGESTED(xprt)) 33075891f50STrond Myklebust clear_bit(XPRT_CWND_WAIT, &xprt->state); 33175891f50STrond Myklebust } 33275891f50STrond Myklebust 33312a80469SChuck Lever /* 33412a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 33512a80469SChuck Lever * @task: task that is requesting access to the transport 33612a80469SChuck Lever * 33712a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 33812a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 33912a80469SChuck Lever * woken up and given access to the transport. 34075891f50STrond Myklebust * Note that the lock is only granted if we know there are free slots. 34112a80469SChuck Lever */ 34243cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 34312a80469SChuck Lever { 3441da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3451da177e4SLinus Torvalds 3462226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 3471da177e4SLinus Torvalds if (task == xprt->snd_task) 348bf7ca707SChuck Lever goto out_locked; 3491da177e4SLinus Torvalds goto out_sleep; 3501da177e4SLinus Torvalds } 35143cedbf0STrond Myklebust if (req == NULL) { 35243cedbf0STrond Myklebust xprt->snd_task = task; 353bf7ca707SChuck Lever goto out_locked; 35443cedbf0STrond Myklebust } 355c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 356c544577dSTrond Myklebust goto out_unlock; 35775891f50STrond Myklebust if (!xprt_need_congestion_window_wait(xprt)) { 3581da177e4SLinus Torvalds xprt->snd_task = task; 359bf7ca707SChuck Lever goto out_locked; 3601da177e4SLinus Torvalds } 361c544577dSTrond Myklebust out_unlock: 362632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3631da177e4SLinus Torvalds out_sleep: 3641da177e4SLinus Torvalds task->tk_status = -EAGAIN; 3656b2e6856STrond Myklebust if (RPC_IS_SOFT(task)) 3666b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->sending, task, NULL, 3679e910bffSTrond Myklebust xprt_request_timeout(req)); 3686b2e6856STrond Myklebust else 36979c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 3701da177e4SLinus Torvalds return 0; 371bf7ca707SChuck Lever out_locked: 372bf7ca707SChuck Lever trace_xprt_reserve_cong(xprt, task); 373bf7ca707SChuck Lever return 1; 3741da177e4SLinus Torvalds } 37512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 3761da177e4SLinus Torvalds 37712a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 3781da177e4SLinus Torvalds { 3791da177e4SLinus Torvalds int retval; 3801da177e4SLinus Torvalds 381bd79bc57STrond Myklebust if (test_bit(XPRT_LOCKED, &xprt->state) && xprt->snd_task == task) 382bd79bc57STrond Myklebust return 1; 383b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 38443cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 385b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 3861da177e4SLinus Torvalds return retval; 3871da177e4SLinus Torvalds } 3881da177e4SLinus Torvalds 389961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 3901da177e4SLinus Torvalds { 391961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 39249e9a890SChuck Lever 39349e9a890SChuck Lever xprt->snd_task = task; 394961a828dSTrond Myklebust return true; 395961a828dSTrond Myklebust } 396961a828dSTrond Myklebust 397961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 398961a828dSTrond Myklebust { 399961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 40049e9a890SChuck Lever return; 401c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 402c544577dSTrond Myklebust goto out_unlock; 403f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 404f1dc237cSTrond Myklebust __xprt_lock_write_func, xprt)) 405961a828dSTrond Myklebust return; 406c544577dSTrond Myklebust out_unlock: 407632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 40849e9a890SChuck Lever } 40949e9a890SChuck Lever 410961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 411961a828dSTrond Myklebust { 412961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 413961a828dSTrond Myklebust return; 414c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 415c544577dSTrond Myklebust goto out_unlock; 41675891f50STrond Myklebust if (xprt_need_congestion_window_wait(xprt)) 417961a828dSTrond Myklebust goto out_unlock; 418f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 41975891f50STrond Myklebust __xprt_lock_write_func, xprt)) 420961a828dSTrond Myklebust return; 4211da177e4SLinus Torvalds out_unlock: 422632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 4231da177e4SLinus Torvalds } 4241da177e4SLinus Torvalds 42549e9a890SChuck Lever /** 42649e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 42749e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 42849e9a890SChuck Lever * @task: task that is releasing access to the transport 42949e9a890SChuck Lever * 43049e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 4311da177e4SLinus Torvalds */ 43249e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 4331da177e4SLinus Torvalds { 4341da177e4SLinus Torvalds if (xprt->snd_task == task) { 435632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 4361da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 4371da177e4SLinus Torvalds } 438bf7ca707SChuck Lever trace_xprt_release_xprt(xprt, task); 4391da177e4SLinus Torvalds } 44012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 4411da177e4SLinus Torvalds 44249e9a890SChuck Lever /** 44349e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 44449e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 44549e9a890SChuck Lever * @task: task that is releasing access to the transport 44649e9a890SChuck Lever * 44749e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 44849e9a890SChuck Lever * transport if the transport's congestion window allows it. 44949e9a890SChuck Lever */ 45049e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 45149e9a890SChuck Lever { 45249e9a890SChuck Lever if (xprt->snd_task == task) { 453632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 45449e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 45549e9a890SChuck Lever } 456bf7ca707SChuck Lever trace_xprt_release_cong(xprt, task); 45749e9a890SChuck Lever } 45812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 45949e9a890SChuck Lever 46049e9a890SChuck Lever static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 4611da177e4SLinus Torvalds { 462bd79bc57STrond Myklebust if (xprt->snd_task != task) 463bd79bc57STrond Myklebust return; 464b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 46549e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 466b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 4671da177e4SLinus Torvalds } 4681da177e4SLinus Torvalds 4691da177e4SLinus Torvalds /* 4701da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 4711da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 4721da177e4SLinus Torvalds */ 4731da177e4SLinus Torvalds static int 47475891f50STrond Myklebust __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4751da177e4SLinus Torvalds { 4761da177e4SLinus Torvalds if (req->rq_cong) 4771da177e4SLinus Torvalds return 1; 478bf7ca707SChuck Lever trace_xprt_get_cong(xprt, req->rq_task); 47975891f50STrond Myklebust if (RPCXPRT_CONGESTED(xprt)) { 48075891f50STrond Myklebust xprt_set_congestion_window_wait(xprt); 4811da177e4SLinus Torvalds return 0; 48275891f50STrond Myklebust } 4831da177e4SLinus Torvalds req->rq_cong = 1; 4841da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 4851da177e4SLinus Torvalds return 1; 4861da177e4SLinus Torvalds } 4871da177e4SLinus Torvalds 4881da177e4SLinus Torvalds /* 4891da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4901da177e4SLinus Torvalds * that has been sleeping due to congestion 4911da177e4SLinus Torvalds */ 4921da177e4SLinus Torvalds static void 4931da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4941da177e4SLinus Torvalds { 4951da177e4SLinus Torvalds if (!req->rq_cong) 4961da177e4SLinus Torvalds return; 4971da177e4SLinus Torvalds req->rq_cong = 0; 4981da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 49975891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(xprt); 500bf7ca707SChuck Lever trace_xprt_put_cong(xprt, req->rq_task); 50149e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 5021da177e4SLinus Torvalds } 5031da177e4SLinus Torvalds 50446c0ee8bSChuck Lever /** 50575891f50STrond Myklebust * xprt_request_get_cong - Request congestion control credits 50675891f50STrond Myklebust * @xprt: pointer to transport 50775891f50STrond Myklebust * @req: pointer to RPC request 50875891f50STrond Myklebust * 50975891f50STrond Myklebust * Useful for transports that require congestion control. 51075891f50STrond Myklebust */ 51175891f50STrond Myklebust bool 51275891f50STrond Myklebust xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 51375891f50STrond Myklebust { 51475891f50STrond Myklebust bool ret = false; 51575891f50STrond Myklebust 51675891f50STrond Myklebust if (req->rq_cong) 51775891f50STrond Myklebust return true; 518b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 51975891f50STrond Myklebust ret = __xprt_get_cong(xprt, req) != 0; 520b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 52175891f50STrond Myklebust return ret; 52275891f50STrond Myklebust } 52375891f50STrond Myklebust EXPORT_SYMBOL_GPL(xprt_request_get_cong); 52475891f50STrond Myklebust 52575891f50STrond Myklebust /** 526a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 527a58dd398SChuck Lever * @task: RPC request that recently completed 528a58dd398SChuck Lever * 529a58dd398SChuck Lever * Useful for transports that require congestion control. 530a58dd398SChuck Lever */ 531a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 532a58dd398SChuck Lever { 533a4f0835cSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 534a4f0835cSTrond Myklebust 535a4f0835cSTrond Myklebust __xprt_put_cong(req->rq_xprt, req); 536a58dd398SChuck Lever } 53712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 538a58dd398SChuck Lever 5398593e010SChuck Lever static void xprt_clear_congestion_window_wait_locked(struct rpc_xprt *xprt) 5408593e010SChuck Lever { 5418593e010SChuck Lever if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) 5428593e010SChuck Lever __xprt_lock_write_next_cong(xprt); 5438593e010SChuck Lever } 5448593e010SChuck Lever 54575891f50STrond Myklebust /* 54675891f50STrond Myklebust * Clear the congestion window wait flag and wake up the next 54775891f50STrond Myklebust * entry on xprt->sending 54875891f50STrond Myklebust */ 54975891f50STrond Myklebust static void 55075891f50STrond Myklebust xprt_clear_congestion_window_wait(struct rpc_xprt *xprt) 55175891f50STrond Myklebust { 55275891f50STrond Myklebust if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) { 553b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 55475891f50STrond Myklebust __xprt_lock_write_next_cong(xprt); 555b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 55675891f50STrond Myklebust } 55775891f50STrond Myklebust } 55875891f50STrond Myklebust 559a58dd398SChuck Lever /** 56046c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 5616a24dfb6STrond Myklebust * @xprt: pointer to xprt 56246c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 56346c0ee8bSChuck Lever * @result: result code of completed RPC request 56446c0ee8bSChuck Lever * 5654f4cf5adSChuck Lever * The transport code maintains an estimate on the maximum number of out- 5664f4cf5adSChuck Lever * standing RPC requests, using a smoothed version of the congestion 5674f4cf5adSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 5684f4cf5adSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 5694f4cf5adSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 5704f4cf5adSChuck Lever * 5714f4cf5adSChuck Lever * - a reply is received and 5724f4cf5adSChuck Lever * - a full number of requests are outstanding and 5734f4cf5adSChuck Lever * - the congestion window hasn't been updated recently. 5741da177e4SLinus Torvalds */ 5756a24dfb6STrond Myklebust void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) 5761da177e4SLinus Torvalds { 57746c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 57846c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 5791da177e4SLinus Torvalds 5801da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 5811da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 5821da177e4SLinus Torvalds * the result gets rounded properly. */ 5831da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 5841da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 5851da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 58649e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 5871da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 5881da177e4SLinus Torvalds cwnd >>= 1; 5891da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 5901da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 5911da177e4SLinus Torvalds } 5921da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 5931da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 5941da177e4SLinus Torvalds xprt->cwnd = cwnd; 59546c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 5961da177e4SLinus Torvalds } 59712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 5981da177e4SLinus Torvalds 59944fbac22SChuck Lever /** 60044fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 60144fbac22SChuck Lever * @xprt: transport with waiting tasks 60244fbac22SChuck Lever * @status: result code to plant in each task before waking it 60344fbac22SChuck Lever * 60444fbac22SChuck Lever */ 60544fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 60644fbac22SChuck Lever { 60744fbac22SChuck Lever if (status < 0) 60844fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 60944fbac22SChuck Lever else 61044fbac22SChuck Lever rpc_wake_up(&xprt->pending); 61144fbac22SChuck Lever } 61212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 61344fbac22SChuck Lever 614c7b2cae8SChuck Lever /** 615c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 616c544577dSTrond Myklebust * @xprt: transport 617a9a6b52eSTrond Myklebust * 618a9a6b52eSTrond Myklebust * Note that we only set the timer for the case of RPC_IS_SOFT(), since 619a9a6b52eSTrond Myklebust * we don't in general want to force a socket disconnection due to 620a9a6b52eSTrond Myklebust * an incomplete RPC call transmission. 621c7b2cae8SChuck Lever */ 622c544577dSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_xprt *xprt) 623c7b2cae8SChuck Lever { 624c544577dSTrond Myklebust set_bit(XPRT_WRITE_SPACE, &xprt->state); 625c7b2cae8SChuck Lever } 62612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 627c7b2cae8SChuck Lever 628c544577dSTrond Myklebust static bool 629c544577dSTrond Myklebust xprt_clear_write_space_locked(struct rpc_xprt *xprt) 630c544577dSTrond Myklebust { 631c544577dSTrond Myklebust if (test_and_clear_bit(XPRT_WRITE_SPACE, &xprt->state)) { 632c544577dSTrond Myklebust __xprt_lock_write_next(xprt); 633c544577dSTrond Myklebust dprintk("RPC: write space: waking waiting task on " 634c544577dSTrond Myklebust "xprt %p\n", xprt); 635c544577dSTrond Myklebust return true; 636c544577dSTrond Myklebust } 637c544577dSTrond Myklebust return false; 638c544577dSTrond Myklebust } 639c544577dSTrond Myklebust 640c7b2cae8SChuck Lever /** 641c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 642c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 643c7b2cae8SChuck Lever * 644c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 645c7b2cae8SChuck Lever */ 646c544577dSTrond Myklebust bool xprt_write_space(struct rpc_xprt *xprt) 647c7b2cae8SChuck Lever { 648c544577dSTrond Myklebust bool ret; 649c544577dSTrond Myklebust 650c544577dSTrond Myklebust if (!test_bit(XPRT_WRITE_SPACE, &xprt->state)) 651c544577dSTrond Myklebust return false; 652b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 653c544577dSTrond Myklebust ret = xprt_clear_write_space_locked(xprt); 654b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 655c544577dSTrond Myklebust return ret; 656c7b2cae8SChuck Lever } 65712444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 658c7b2cae8SChuck Lever 659da953063STrond Myklebust static unsigned long xprt_abs_ktime_to_jiffies(ktime_t abstime) 660da953063STrond Myklebust { 661da953063STrond Myklebust s64 delta = ktime_to_ns(ktime_get() - abstime); 662da953063STrond Myklebust return likely(delta >= 0) ? 663da953063STrond Myklebust jiffies - nsecs_to_jiffies(delta) : 664da953063STrond Myklebust jiffies + nsecs_to_jiffies(-delta); 665da953063STrond Myklebust } 666da953063STrond Myklebust 667da953063STrond Myklebust static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req) 6681da177e4SLinus Torvalds { 669ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 670da953063STrond Myklebust unsigned long majortimeo = req->rq_timeout; 6711da177e4SLinus Torvalds 6721da177e4SLinus Torvalds if (to->to_exponential) 673da953063STrond Myklebust majortimeo <<= to->to_retries; 6741da177e4SLinus Torvalds else 675da953063STrond Myklebust majortimeo += to->to_increment * to->to_retries; 676da953063STrond Myklebust if (majortimeo > to->to_maxval || majortimeo == 0) 677da953063STrond Myklebust majortimeo = to->to_maxval; 678da953063STrond Myklebust return majortimeo; 679da953063STrond Myklebust } 680da953063STrond Myklebust 681da953063STrond Myklebust static void xprt_reset_majortimeo(struct rpc_rqst *req) 682da953063STrond Myklebust { 683da953063STrond Myklebust req->rq_majortimeo += xprt_calc_majortimeo(req); 684da953063STrond Myklebust } 685da953063STrond Myklebust 6867de62bc0SOlga Kornievskaia static void xprt_reset_minortimeo(struct rpc_rqst *req) 6877de62bc0SOlga Kornievskaia { 6887de62bc0SOlga Kornievskaia req->rq_minortimeo += req->rq_timeout; 6897de62bc0SOlga Kornievskaia } 6907de62bc0SOlga Kornievskaia 691da953063STrond Myklebust static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req) 692da953063STrond Myklebust { 693da953063STrond Myklebust unsigned long time_init; 694da953063STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 695da953063STrond Myklebust 696da953063STrond Myklebust if (likely(xprt && xprt_connected(xprt))) 697da953063STrond Myklebust time_init = jiffies; 698da953063STrond Myklebust else 699da953063STrond Myklebust time_init = xprt_abs_ktime_to_jiffies(task->tk_start); 700da953063STrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 701da953063STrond Myklebust req->rq_majortimeo = time_init + xprt_calc_majortimeo(req); 7027de62bc0SOlga Kornievskaia req->rq_minortimeo = time_init + req->rq_timeout; 7031da177e4SLinus Torvalds } 7041da177e4SLinus Torvalds 7059903cd1cSChuck Lever /** 7069903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 7079903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 7089903cd1cSChuck Lever * 7091da177e4SLinus Torvalds */ 7101da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 7111da177e4SLinus Torvalds { 7121da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 713ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 7141da177e4SLinus Torvalds int status = 0; 7151da177e4SLinus Torvalds 7167de62bc0SOlga Kornievskaia if (time_before(jiffies, req->rq_minortimeo)) 7177de62bc0SOlga Kornievskaia return status; 7181da177e4SLinus Torvalds if (time_before(jiffies, req->rq_majortimeo)) { 7191da177e4SLinus Torvalds if (to->to_exponential) 7201da177e4SLinus Torvalds req->rq_timeout <<= 1; 7211da177e4SLinus Torvalds else 7221da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 7231da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 7241da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 7251da177e4SLinus Torvalds req->rq_retries++; 7261da177e4SLinus Torvalds } else { 7271da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 7281da177e4SLinus Torvalds req->rq_retries = 0; 7291da177e4SLinus Torvalds xprt_reset_majortimeo(req); 7301da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 731b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 7321da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 733b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 7341da177e4SLinus Torvalds status = -ETIMEDOUT; 7351da177e4SLinus Torvalds } 7367de62bc0SOlga Kornievskaia xprt_reset_minortimeo(req); 7371da177e4SLinus Torvalds 7381da177e4SLinus Torvalds if (req->rq_timeout == 0) { 7391da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 7401da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 7411da177e4SLinus Torvalds } 7421da177e4SLinus Torvalds return status; 7431da177e4SLinus Torvalds } 7441da177e4SLinus Torvalds 74565f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 7461da177e4SLinus Torvalds { 74765f27f38SDavid Howells struct rpc_xprt *xprt = 74865f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 749a1231fdaSTrond Myklebust unsigned int pflags = memalloc_nofs_save(); 7501da177e4SLinus Torvalds 751911813d7SChuck Lever trace_xprt_disconnect_auto(xprt); 75266af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 7534876cc77STrond Myklebust xprt->ops->close(xprt); 7541da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 75579234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 756a1231fdaSTrond Myklebust memalloc_nofs_restore(pflags); 7571da177e4SLinus Torvalds } 7581da177e4SLinus Torvalds 7599903cd1cSChuck Lever /** 76062da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 7619903cd1cSChuck Lever * @xprt: transport to flag for disconnect 7629903cd1cSChuck Lever * 7631da177e4SLinus Torvalds */ 76462da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 7651da177e4SLinus Torvalds { 766911813d7SChuck Lever trace_xprt_disconnect_done(xprt); 767b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 7681da177e4SLinus Torvalds xprt_clear_connected(xprt); 769c544577dSTrond Myklebust xprt_clear_write_space_locked(xprt); 7708593e010SChuck Lever xprt_clear_congestion_window_wait_locked(xprt); 77127adc785STrond Myklebust xprt_wake_pending_tasks(xprt, -ENOTCONN); 772b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 7731da177e4SLinus Torvalds } 77462da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 7751da177e4SLinus Torvalds 77666af1e55STrond Myklebust /** 77766af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 77866af1e55STrond Myklebust * @xprt: transport to disconnect 77966af1e55STrond Myklebust * 78066af1e55STrond Myklebust */ 78166af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 78266af1e55STrond Myklebust { 783911813d7SChuck Lever trace_xprt_disconnect_force(xprt); 784911813d7SChuck Lever 78566af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 786b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 78766af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 78866af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 78966af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 79040a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 7910445f92cSTrond Myklebust else if (xprt->snd_task) 7920445f92cSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 7930445f92cSTrond Myklebust xprt->snd_task, -ENOTCONN); 794b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 79566af1e55STrond Myklebust } 796e2a4f4fbSChuck Lever EXPORT_SYMBOL_GPL(xprt_force_disconnect); 79766af1e55STrond Myklebust 7987f3a1d1eSTrond Myklebust static unsigned int 7997f3a1d1eSTrond Myklebust xprt_connect_cookie(struct rpc_xprt *xprt) 8007f3a1d1eSTrond Myklebust { 8017f3a1d1eSTrond Myklebust return READ_ONCE(xprt->connect_cookie); 8027f3a1d1eSTrond Myklebust } 8037f3a1d1eSTrond Myklebust 8047f3a1d1eSTrond Myklebust static bool 8057f3a1d1eSTrond Myklebust xprt_request_retransmit_after_disconnect(struct rpc_task *task) 8067f3a1d1eSTrond Myklebust { 8077f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 8087f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 8097f3a1d1eSTrond Myklebust 8107f3a1d1eSTrond Myklebust return req->rq_connect_cookie != xprt_connect_cookie(xprt) || 8117f3a1d1eSTrond Myklebust !xprt_connected(xprt); 8127f3a1d1eSTrond Myklebust } 8137f3a1d1eSTrond Myklebust 8147c1d71cfSTrond Myklebust /** 8157c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 8167c1d71cfSTrond Myklebust * @xprt: transport to disconnect 8177c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 8187c1d71cfSTrond Myklebust * 8197c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 8207c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 8217c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 8227c1d71cfSTrond Myklebust * a batch of RPC requests. 8237c1d71cfSTrond Myklebust * 8247c1d71cfSTrond Myklebust */ 8257c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 8267c1d71cfSTrond Myklebust { 8277c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 828b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 8297c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 8307c1d71cfSTrond Myklebust goto out; 8312c2ee6d2SNeilBrown if (test_bit(XPRT_CLOSING, &xprt->state)) 8327c1d71cfSTrond Myklebust goto out; 8337c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 8347c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 8357c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 83640a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 8372a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 8387c1d71cfSTrond Myklebust out: 839b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 8407c1d71cfSTrond Myklebust } 8417c1d71cfSTrond Myklebust 842ad3331acSTrond Myklebust static bool 843ad3331acSTrond Myklebust xprt_has_timer(const struct rpc_xprt *xprt) 844ad3331acSTrond Myklebust { 845ad3331acSTrond Myklebust return xprt->idle_timeout != 0; 846ad3331acSTrond Myklebust } 847ad3331acSTrond Myklebust 848ad3331acSTrond Myklebust static void 849ad3331acSTrond Myklebust xprt_schedule_autodisconnect(struct rpc_xprt *xprt) 850ad3331acSTrond Myklebust __must_hold(&xprt->transport_lock) 851ad3331acSTrond Myklebust { 85280d3c45fSDave Wysochanski xprt->last_used = jiffies; 85395f7691dSTrond Myklebust if (RB_EMPTY_ROOT(&xprt->recv_queue) && xprt_has_timer(xprt)) 854ad3331acSTrond Myklebust mod_timer(&xprt->timer, xprt->last_used + xprt->idle_timeout); 855ad3331acSTrond Myklebust } 856ad3331acSTrond Myklebust 8571da177e4SLinus Torvalds static void 858ff861c4dSKees Cook xprt_init_autodisconnect(struct timer_list *t) 8591da177e4SLinus Torvalds { 860ff861c4dSKees Cook struct rpc_xprt *xprt = from_timer(xprt, t, timer); 8611da177e4SLinus Torvalds 86295f7691dSTrond Myklebust if (!RB_EMPTY_ROOT(&xprt->recv_queue)) 863b5e92419STrond Myklebust return; 864ad3331acSTrond Myklebust /* Reset xprt->last_used to avoid connect/autodisconnect cycling */ 865ad3331acSTrond Myklebust xprt->last_used = jiffies; 8662226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 8671da177e4SLinus Torvalds return; 868b5e92419STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 8691da177e4SLinus Torvalds } 8701da177e4SLinus Torvalds 871718ba5b8STrond Myklebust bool xprt_lock_connect(struct rpc_xprt *xprt, 872718ba5b8STrond Myklebust struct rpc_task *task, 873718ba5b8STrond Myklebust void *cookie) 874718ba5b8STrond Myklebust { 875718ba5b8STrond Myklebust bool ret = false; 876718ba5b8STrond Myklebust 877b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 878718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 879718ba5b8STrond Myklebust goto out; 880718ba5b8STrond Myklebust if (xprt->snd_task != task) 881718ba5b8STrond Myklebust goto out; 882718ba5b8STrond Myklebust xprt->snd_task = cookie; 883718ba5b8STrond Myklebust ret = true; 884718ba5b8STrond Myklebust out: 885b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 886718ba5b8STrond Myklebust return ret; 887718ba5b8STrond Myklebust } 888718ba5b8STrond Myklebust 889718ba5b8STrond Myklebust void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) 890718ba5b8STrond Myklebust { 891b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 892718ba5b8STrond Myklebust if (xprt->snd_task != cookie) 893718ba5b8STrond Myklebust goto out; 894718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 895718ba5b8STrond Myklebust goto out; 896718ba5b8STrond Myklebust xprt->snd_task =NULL; 897718ba5b8STrond Myklebust xprt->ops->release_xprt(xprt, NULL); 898ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 899718ba5b8STrond Myklebust out: 900b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 90179234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 902718ba5b8STrond Myklebust } 903718ba5b8STrond Myklebust 9049903cd1cSChuck Lever /** 9059903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 9069903cd1cSChuck Lever * @task: RPC task that is requesting the connect 9071da177e4SLinus Torvalds * 9081da177e4SLinus Torvalds */ 9091da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 9101da177e4SLinus Torvalds { 911ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 9121da177e4SLinus Torvalds 913db0a86c4SChuck Lever trace_xprt_connect(xprt); 9141da177e4SLinus Torvalds 915ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 91601d37c42STrond Myklebust task->tk_status = -EAGAIN; 9171da177e4SLinus Torvalds return; 9181da177e4SLinus Torvalds } 9191da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 9201da177e4SLinus Torvalds return; 921feb8ca37STrond Myklebust 922911813d7SChuck Lever if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 923911813d7SChuck Lever trace_xprt_disconnect_cleanup(xprt); 924feb8ca37STrond Myklebust xprt->ops->close(xprt); 925911813d7SChuck Lever } 926feb8ca37STrond Myklebust 927718ba5b8STrond Myklebust if (!xprt_connected(xprt)) { 9282c2ee6d2SNeilBrown task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie; 9296b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->pending, task, NULL, 9309e910bffSTrond Myklebust xprt_request_timeout(task->tk_rqstp)); 9310b9e7943STrond Myklebust 9320b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 9330b9e7943STrond Myklebust return; 9340b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 9350b9e7943STrond Myklebust return; 9360a9a4304STrond Myklebust /* Race breaker */ 9370a9a4304STrond Myklebust if (!xprt_connected(xprt)) { 938262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 9391b092092STrond Myklebust xprt->ops->connect(xprt, task); 9400a9a4304STrond Myklebust } else { 9410a9a4304STrond Myklebust xprt_clear_connecting(xprt); 9420a9a4304STrond Myklebust task->tk_status = 0; 9430a9a4304STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 9440a9a4304STrond Myklebust } 9451da177e4SLinus Torvalds } 946718ba5b8STrond Myklebust xprt_release_write(xprt, task); 9471da177e4SLinus Torvalds } 9481da177e4SLinus Torvalds 949675dd90aSChuck Lever /** 950675dd90aSChuck Lever * xprt_reconnect_delay - compute the wait before scheduling a connect 951675dd90aSChuck Lever * @xprt: transport instance 952675dd90aSChuck Lever * 953675dd90aSChuck Lever */ 954675dd90aSChuck Lever unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt) 955675dd90aSChuck Lever { 956675dd90aSChuck Lever unsigned long start, now = jiffies; 957675dd90aSChuck Lever 958675dd90aSChuck Lever start = xprt->stat.connect_start + xprt->reestablish_timeout; 959675dd90aSChuck Lever if (time_after(start, now)) 960675dd90aSChuck Lever return start - now; 961675dd90aSChuck Lever return 0; 962675dd90aSChuck Lever } 963675dd90aSChuck Lever EXPORT_SYMBOL_GPL(xprt_reconnect_delay); 964675dd90aSChuck Lever 965675dd90aSChuck Lever /** 966675dd90aSChuck Lever * xprt_reconnect_backoff - compute the new re-establish timeout 967675dd90aSChuck Lever * @xprt: transport instance 968675dd90aSChuck Lever * @init_to: initial reestablish timeout 969675dd90aSChuck Lever * 970675dd90aSChuck Lever */ 971675dd90aSChuck Lever void xprt_reconnect_backoff(struct rpc_xprt *xprt, unsigned long init_to) 972675dd90aSChuck Lever { 973675dd90aSChuck Lever xprt->reestablish_timeout <<= 1; 974675dd90aSChuck Lever if (xprt->reestablish_timeout > xprt->max_reconnect_timeout) 975675dd90aSChuck Lever xprt->reestablish_timeout = xprt->max_reconnect_timeout; 976675dd90aSChuck Lever if (xprt->reestablish_timeout < init_to) 977675dd90aSChuck Lever xprt->reestablish_timeout = init_to; 978675dd90aSChuck Lever } 979675dd90aSChuck Lever EXPORT_SYMBOL_GPL(xprt_reconnect_backoff); 980675dd90aSChuck Lever 98195f7691dSTrond Myklebust enum xprt_xid_rb_cmp { 98295f7691dSTrond Myklebust XID_RB_EQUAL, 98395f7691dSTrond Myklebust XID_RB_LEFT, 98495f7691dSTrond Myklebust XID_RB_RIGHT, 98595f7691dSTrond Myklebust }; 98695f7691dSTrond Myklebust static enum xprt_xid_rb_cmp 98795f7691dSTrond Myklebust xprt_xid_cmp(__be32 xid1, __be32 xid2) 98895f7691dSTrond Myklebust { 98995f7691dSTrond Myklebust if (xid1 == xid2) 99095f7691dSTrond Myklebust return XID_RB_EQUAL; 99195f7691dSTrond Myklebust if ((__force u32)xid1 < (__force u32)xid2) 99295f7691dSTrond Myklebust return XID_RB_LEFT; 99395f7691dSTrond Myklebust return XID_RB_RIGHT; 99495f7691dSTrond Myklebust } 99595f7691dSTrond Myklebust 99695f7691dSTrond Myklebust static struct rpc_rqst * 99795f7691dSTrond Myklebust xprt_request_rb_find(struct rpc_xprt *xprt, __be32 xid) 99895f7691dSTrond Myklebust { 99995f7691dSTrond Myklebust struct rb_node *n = xprt->recv_queue.rb_node; 100095f7691dSTrond Myklebust struct rpc_rqst *req; 100195f7691dSTrond Myklebust 100295f7691dSTrond Myklebust while (n != NULL) { 100395f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 100495f7691dSTrond Myklebust switch (xprt_xid_cmp(xid, req->rq_xid)) { 100595f7691dSTrond Myklebust case XID_RB_LEFT: 100695f7691dSTrond Myklebust n = n->rb_left; 100795f7691dSTrond Myklebust break; 100895f7691dSTrond Myklebust case XID_RB_RIGHT: 100995f7691dSTrond Myklebust n = n->rb_right; 101095f7691dSTrond Myklebust break; 101195f7691dSTrond Myklebust case XID_RB_EQUAL: 101295f7691dSTrond Myklebust return req; 101395f7691dSTrond Myklebust } 101495f7691dSTrond Myklebust } 101595f7691dSTrond Myklebust return NULL; 101695f7691dSTrond Myklebust } 101795f7691dSTrond Myklebust 101895f7691dSTrond Myklebust static void 101995f7691dSTrond Myklebust xprt_request_rb_insert(struct rpc_xprt *xprt, struct rpc_rqst *new) 102095f7691dSTrond Myklebust { 102195f7691dSTrond Myklebust struct rb_node **p = &xprt->recv_queue.rb_node; 102295f7691dSTrond Myklebust struct rb_node *n = NULL; 102395f7691dSTrond Myklebust struct rpc_rqst *req; 102495f7691dSTrond Myklebust 102595f7691dSTrond Myklebust while (*p != NULL) { 102695f7691dSTrond Myklebust n = *p; 102795f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 102895f7691dSTrond Myklebust switch(xprt_xid_cmp(new->rq_xid, req->rq_xid)) { 102995f7691dSTrond Myklebust case XID_RB_LEFT: 103095f7691dSTrond Myklebust p = &n->rb_left; 103195f7691dSTrond Myklebust break; 103295f7691dSTrond Myklebust case XID_RB_RIGHT: 103395f7691dSTrond Myklebust p = &n->rb_right; 103495f7691dSTrond Myklebust break; 103595f7691dSTrond Myklebust case XID_RB_EQUAL: 103695f7691dSTrond Myklebust WARN_ON_ONCE(new != req); 103795f7691dSTrond Myklebust return; 103895f7691dSTrond Myklebust } 103995f7691dSTrond Myklebust } 104095f7691dSTrond Myklebust rb_link_node(&new->rq_recv, n, p); 104195f7691dSTrond Myklebust rb_insert_color(&new->rq_recv, &xprt->recv_queue); 104295f7691dSTrond Myklebust } 104395f7691dSTrond Myklebust 104495f7691dSTrond Myklebust static void 104595f7691dSTrond Myklebust xprt_request_rb_remove(struct rpc_xprt *xprt, struct rpc_rqst *req) 104695f7691dSTrond Myklebust { 104795f7691dSTrond Myklebust rb_erase(&req->rq_recv, &xprt->recv_queue); 104895f7691dSTrond Myklebust } 104995f7691dSTrond Myklebust 10509903cd1cSChuck Lever /** 10519903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 10529903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 10539903cd1cSChuck Lever * @xid: RPC XID of incoming reply 10549903cd1cSChuck Lever * 105575c84151STrond Myklebust * Caller holds xprt->queue_lock. 10561da177e4SLinus Torvalds */ 1057d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 10581da177e4SLinus Torvalds { 10598f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 10601da177e4SLinus Torvalds 106195f7691dSTrond Myklebust entry = xprt_request_rb_find(xprt, xid); 106295f7691dSTrond Myklebust if (entry != NULL) { 10633705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, 0); 10640b87a46bSChuck Lever entry->rq_rtt = ktime_sub(ktime_get(), entry->rq_xtime); 1065262ca07dSChuck Lever return entry; 10663705ad64SJeff Layton } 106746121cf7SChuck Lever 106846121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 106946121cf7SChuck Lever ntohl(xid)); 10703705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, -ENOENT); 1071262ca07dSChuck Lever xprt->stat.bad_xids++; 1072262ca07dSChuck Lever return NULL; 10731da177e4SLinus Torvalds } 107412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 10751da177e4SLinus Torvalds 1076cf9946cdSTrond Myklebust static bool 1077cf9946cdSTrond Myklebust xprt_is_pinned_rqst(struct rpc_rqst *req) 1078cf9946cdSTrond Myklebust { 1079cf9946cdSTrond Myklebust return atomic_read(&req->rq_pin) != 0; 1080cf9946cdSTrond Myklebust } 1081cf9946cdSTrond Myklebust 1082729749bbSTrond Myklebust /** 1083729749bbSTrond Myklebust * xprt_pin_rqst - Pin a request on the transport receive list 1084729749bbSTrond Myklebust * @req: Request to pin 1085729749bbSTrond Myklebust * 1086729749bbSTrond Myklebust * Caller must ensure this is atomic with the call to xprt_lookup_rqst() 10871f7d1c73SChuck Lever * so should be holding xprt->queue_lock. 1088729749bbSTrond Myklebust */ 1089729749bbSTrond Myklebust void xprt_pin_rqst(struct rpc_rqst *req) 1090729749bbSTrond Myklebust { 1091cf9946cdSTrond Myklebust atomic_inc(&req->rq_pin); 1092729749bbSTrond Myklebust } 10939590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_pin_rqst); 1094729749bbSTrond Myklebust 1095729749bbSTrond Myklebust /** 1096729749bbSTrond Myklebust * xprt_unpin_rqst - Unpin a request on the transport receive list 1097729749bbSTrond Myklebust * @req: Request to pin 1098729749bbSTrond Myklebust * 10991f7d1c73SChuck Lever * Caller should be holding xprt->queue_lock. 1100729749bbSTrond Myklebust */ 1101729749bbSTrond Myklebust void xprt_unpin_rqst(struct rpc_rqst *req) 1102729749bbSTrond Myklebust { 1103cf9946cdSTrond Myklebust if (!test_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate)) { 1104cf9946cdSTrond Myklebust atomic_dec(&req->rq_pin); 1105cf9946cdSTrond Myklebust return; 1106cf9946cdSTrond Myklebust } 1107cf9946cdSTrond Myklebust if (atomic_dec_and_test(&req->rq_pin)) 1108cf9946cdSTrond Myklebust wake_up_var(&req->rq_pin); 1109729749bbSTrond Myklebust } 11109590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_unpin_rqst); 1111729749bbSTrond Myklebust 1112729749bbSTrond Myklebust static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) 1113729749bbSTrond Myklebust { 1114cf9946cdSTrond Myklebust wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); 1115729749bbSTrond Myklebust } 1116729749bbSTrond Myklebust 1117edc81dcdSTrond Myklebust static bool 1118edc81dcdSTrond Myklebust xprt_request_data_received(struct rpc_task *task) 1119edc81dcdSTrond Myklebust { 1120edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 1121edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; 1122edc81dcdSTrond Myklebust } 1123edc81dcdSTrond Myklebust 1124edc81dcdSTrond Myklebust static bool 1125edc81dcdSTrond Myklebust xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst *req) 1126edc81dcdSTrond Myklebust { 1127edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 1128edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) == 0; 1129edc81dcdSTrond Myklebust } 1130edc81dcdSTrond Myklebust 1131edc81dcdSTrond Myklebust /** 1132edc81dcdSTrond Myklebust * xprt_request_enqueue_receive - Add an request to the receive queue 1133edc81dcdSTrond Myklebust * @task: RPC task 1134edc81dcdSTrond Myklebust * 1135edc81dcdSTrond Myklebust */ 1136edc81dcdSTrond Myklebust void 1137edc81dcdSTrond Myklebust xprt_request_enqueue_receive(struct rpc_task *task) 1138edc81dcdSTrond Myklebust { 1139edc81dcdSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1140edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1141edc81dcdSTrond Myklebust 1142edc81dcdSTrond Myklebust if (!xprt_request_need_enqueue_receive(task, req)) 1143edc81dcdSTrond Myklebust return; 114475369089STrond Myklebust 114575369089STrond Myklebust xprt_request_prepare(task->tk_rqstp); 1146edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1147edc81dcdSTrond Myklebust 1148edc81dcdSTrond Myklebust /* Update the softirq receive buffer */ 1149edc81dcdSTrond Myklebust memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 1150edc81dcdSTrond Myklebust sizeof(req->rq_private_buf)); 1151edc81dcdSTrond Myklebust 1152edc81dcdSTrond Myklebust /* Add request to the receive list */ 115395f7691dSTrond Myklebust xprt_request_rb_insert(xprt, req); 1154edc81dcdSTrond Myklebust set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); 1155edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1156edc81dcdSTrond Myklebust 1157edc81dcdSTrond Myklebust /* Turn off autodisconnect */ 1158edc81dcdSTrond Myklebust del_singleshot_timer_sync(&xprt->timer); 1159edc81dcdSTrond Myklebust } 1160edc81dcdSTrond Myklebust 1161edc81dcdSTrond Myklebust /** 1162edc81dcdSTrond Myklebust * xprt_request_dequeue_receive_locked - Remove a request from the receive queue 1163edc81dcdSTrond Myklebust * @task: RPC task 1164edc81dcdSTrond Myklebust * 1165edc81dcdSTrond Myklebust * Caller must hold xprt->queue_lock. 1166edc81dcdSTrond Myklebust */ 1167edc81dcdSTrond Myklebust static void 1168edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(struct rpc_task *task) 1169edc81dcdSTrond Myklebust { 117095f7691dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 117195f7691dSTrond Myklebust 1172edc81dcdSTrond Myklebust if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 117395f7691dSTrond Myklebust xprt_request_rb_remove(req->rq_xprt, req); 1174edc81dcdSTrond Myklebust } 1175edc81dcdSTrond Myklebust 1176ecd465eeSChuck Lever /** 1177ecd465eeSChuck Lever * xprt_update_rtt - Update RPC RTT statistics 1178ecd465eeSChuck Lever * @task: RPC request that recently completed 1179ecd465eeSChuck Lever * 118075c84151STrond Myklebust * Caller holds xprt->queue_lock. 1181ecd465eeSChuck Lever */ 1182ecd465eeSChuck Lever void xprt_update_rtt(struct rpc_task *task) 11831da177e4SLinus Torvalds { 11841570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 11851570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 118695c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 1187d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 11881570c1e4SChuck Lever 11891da177e4SLinus Torvalds if (timer) { 11901da177e4SLinus Torvalds if (req->rq_ntrans == 1) 1191ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 11921570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 11931da177e4SLinus Torvalds } 11941da177e4SLinus Torvalds } 1195ecd465eeSChuck Lever EXPORT_SYMBOL_GPL(xprt_update_rtt); 11961da177e4SLinus Torvalds 11971570c1e4SChuck Lever /** 11981570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 11991570c1e4SChuck Lever * @task: RPC request that recently completed 12001570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 12011570c1e4SChuck Lever * 120275c84151STrond Myklebust * Caller holds xprt->queue_lock. 12031570c1e4SChuck Lever */ 12041570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 12051570c1e4SChuck Lever { 12061570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 1207fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12081da177e4SLinus Torvalds 1209fda13939STrond Myklebust xprt->stat.recvs++; 1210ef759a2eSChuck Lever 12111e799b67STrond Myklebust req->rq_private_buf.len = copied; 1212dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 1213dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 121443ac3f29STrond Myklebust smp_wmb(); 1215dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 1216edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 1217fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 12181da177e4SLinus Torvalds } 121912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 12201da177e4SLinus Torvalds 122146c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 12221da177e4SLinus Torvalds { 12231da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 12241da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 12251da177e4SLinus Torvalds 12265d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 12275d00837bSTrond Myklebust return; 122846c0ee8bSChuck Lever 122982476d9fSChuck Lever trace_xprt_timer(xprt, req->rq_xid, task->tk_status); 1230dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 123146c0ee8bSChuck Lever if (xprt->ops->timer) 12326a24dfb6STrond Myklebust xprt->ops->timer(xprt, task); 12335d00837bSTrond Myklebust } else 12345d00837bSTrond Myklebust task->tk_status = 0; 12351da177e4SLinus Torvalds } 12361da177e4SLinus Torvalds 12379903cd1cSChuck Lever /** 12388ba6a92dSTrond Myklebust * xprt_wait_for_reply_request_def - wait for reply 12398ba6a92dSTrond Myklebust * @task: pointer to rpc_task 12408ba6a92dSTrond Myklebust * 12418ba6a92dSTrond Myklebust * Set a request's retransmit timeout based on the transport's 12428ba6a92dSTrond Myklebust * default timeout parameters. Used by transports that don't adjust 12438ba6a92dSTrond Myklebust * the retransmit timeout based on round-trip time estimation, 12448ba6a92dSTrond Myklebust * and put the task to sleep on the pending queue. 12458ba6a92dSTrond Myklebust */ 12468ba6a92dSTrond Myklebust void xprt_wait_for_reply_request_def(struct rpc_task *task) 12478ba6a92dSTrond Myklebust { 12488ba6a92dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12498ba6a92dSTrond Myklebust 12506b2e6856STrond Myklebust rpc_sleep_on_timeout(&req->rq_xprt->pending, task, xprt_timer, 12519e910bffSTrond Myklebust xprt_request_timeout(req)); 12528ba6a92dSTrond Myklebust } 12538ba6a92dSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_wait_for_reply_request_def); 12548ba6a92dSTrond Myklebust 12558ba6a92dSTrond Myklebust /** 12568ba6a92dSTrond Myklebust * xprt_wait_for_reply_request_rtt - wait for reply using RTT estimator 12578ba6a92dSTrond Myklebust * @task: pointer to rpc_task 12588ba6a92dSTrond Myklebust * 12598ba6a92dSTrond Myklebust * Set a request's retransmit timeout using the RTT estimator, 12608ba6a92dSTrond Myklebust * and put the task to sleep on the pending queue. 12618ba6a92dSTrond Myklebust */ 12628ba6a92dSTrond Myklebust void xprt_wait_for_reply_request_rtt(struct rpc_task *task) 12638ba6a92dSTrond Myklebust { 12648ba6a92dSTrond Myklebust int timer = task->tk_msg.rpc_proc->p_timer; 12658ba6a92dSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 12668ba6a92dSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 12678ba6a92dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12688ba6a92dSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 12696b2e6856STrond Myklebust unsigned long timeout; 12708ba6a92dSTrond Myklebust 12716b2e6856STrond Myklebust timeout = rpc_calc_rto(rtt, timer); 12726b2e6856STrond Myklebust timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 12736b2e6856STrond Myklebust if (timeout > max_timeout || timeout == 0) 12746b2e6856STrond Myklebust timeout = max_timeout; 12756b2e6856STrond Myklebust rpc_sleep_on_timeout(&req->rq_xprt->pending, task, xprt_timer, 12766b2e6856STrond Myklebust jiffies + timeout); 12778ba6a92dSTrond Myklebust } 12788ba6a92dSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_wait_for_reply_request_rtt); 12798ba6a92dSTrond Myklebust 12808ba6a92dSTrond Myklebust /** 12817f3a1d1eSTrond Myklebust * xprt_request_wait_receive - wait for the reply to an RPC request 12827f3a1d1eSTrond Myklebust * @task: RPC task about to send a request 12837f3a1d1eSTrond Myklebust * 12847f3a1d1eSTrond Myklebust */ 12857f3a1d1eSTrond Myklebust void xprt_request_wait_receive(struct rpc_task *task) 12867f3a1d1eSTrond Myklebust { 12877f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12887f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12897f3a1d1eSTrond Myklebust 12907f3a1d1eSTrond Myklebust if (!test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 12917f3a1d1eSTrond Myklebust return; 12927f3a1d1eSTrond Myklebust /* 12937f3a1d1eSTrond Myklebust * Sleep on the pending queue if we're expecting a reply. 12947f3a1d1eSTrond Myklebust * The spinlock ensures atomicity between the test of 12957f3a1d1eSTrond Myklebust * req->rq_reply_bytes_recvd, and the call to rpc_sleep_on(). 12967f3a1d1eSTrond Myklebust */ 12977f3a1d1eSTrond Myklebust spin_lock(&xprt->queue_lock); 12987f3a1d1eSTrond Myklebust if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) { 12998ba6a92dSTrond Myklebust xprt->ops->wait_for_reply_request(task); 13007f3a1d1eSTrond Myklebust /* 13017f3a1d1eSTrond Myklebust * Send an extra queue wakeup call if the 13027f3a1d1eSTrond Myklebust * connection was dropped in case the call to 13037f3a1d1eSTrond Myklebust * rpc_sleep_on() raced. 13047f3a1d1eSTrond Myklebust */ 13057f3a1d1eSTrond Myklebust if (xprt_request_retransmit_after_disconnect(task)) 13067f3a1d1eSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 13077f3a1d1eSTrond Myklebust task, -ENOTCONN); 13087f3a1d1eSTrond Myklebust } 13097f3a1d1eSTrond Myklebust spin_unlock(&xprt->queue_lock); 13107f3a1d1eSTrond Myklebust } 13117f3a1d1eSTrond Myklebust 1312944b0429STrond Myklebust static bool 1313944b0429STrond Myklebust xprt_request_need_enqueue_transmit(struct rpc_task *task, struct rpc_rqst *req) 1314944b0429STrond Myklebust { 1315762e4e67STrond Myklebust return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1316944b0429STrond Myklebust } 1317944b0429STrond Myklebust 1318944b0429STrond Myklebust /** 1319944b0429STrond Myklebust * xprt_request_enqueue_transmit - queue a task for transmission 1320944b0429STrond Myklebust * @task: pointer to rpc_task 1321944b0429STrond Myklebust * 1322944b0429STrond Myklebust * Add a task to the transmission queue. 1323944b0429STrond Myklebust */ 1324944b0429STrond Myklebust void 1325944b0429STrond Myklebust xprt_request_enqueue_transmit(struct rpc_task *task) 1326944b0429STrond Myklebust { 1327918f3c1fSTrond Myklebust struct rpc_rqst *pos, *req = task->tk_rqstp; 1328944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1329944b0429STrond Myklebust 1330944b0429STrond Myklebust if (xprt_request_need_enqueue_transmit(task, req)) { 1331e66721f0STrond Myklebust req->rq_bytes_sent = 0; 1332944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 133375891f50STrond Myklebust /* 133475891f50STrond Myklebust * Requests that carry congestion control credits are added 133575891f50STrond Myklebust * to the head of the list to avoid starvation issues. 133675891f50STrond Myklebust */ 133775891f50STrond Myklebust if (req->rq_cong) { 133875891f50STrond Myklebust xprt_clear_congestion_window_wait(xprt); 133975891f50STrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 134075891f50STrond Myklebust if (pos->rq_cong) 134175891f50STrond Myklebust continue; 134275891f50STrond Myklebust /* Note: req is added _before_ pos */ 134375891f50STrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 134475891f50STrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 134575891f50STrond Myklebust goto out; 134675891f50STrond Myklebust } 134786aeee0eSTrond Myklebust } else if (RPC_IS_SWAPPER(task)) { 134886aeee0eSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 134986aeee0eSTrond Myklebust if (pos->rq_cong || pos->rq_bytes_sent) 135086aeee0eSTrond Myklebust continue; 135186aeee0eSTrond Myklebust if (RPC_IS_SWAPPER(pos->rq_task)) 135286aeee0eSTrond Myklebust continue; 135386aeee0eSTrond Myklebust /* Note: req is added _before_ pos */ 135486aeee0eSTrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 135586aeee0eSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 135686aeee0eSTrond Myklebust goto out; 135786aeee0eSTrond Myklebust } 1358deaa5c96SChuck Lever } else if (!req->rq_seqno) { 1359918f3c1fSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 1360918f3c1fSTrond Myklebust if (pos->rq_task->tk_owner != task->tk_owner) 1361918f3c1fSTrond Myklebust continue; 1362918f3c1fSTrond Myklebust list_add_tail(&req->rq_xmit2, &pos->rq_xmit2); 1363918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit); 1364918f3c1fSTrond Myklebust goto out; 1365918f3c1fSTrond Myklebust } 136675891f50STrond Myklebust } 1367944b0429STrond Myklebust list_add_tail(&req->rq_xmit, &xprt->xmit_queue); 1368918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 1369918f3c1fSTrond Myklebust out: 1370944b0429STrond Myklebust set_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1371944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1372944b0429STrond Myklebust } 1373944b0429STrond Myklebust } 1374944b0429STrond Myklebust 1375944b0429STrond Myklebust /** 1376944b0429STrond Myklebust * xprt_request_dequeue_transmit_locked - remove a task from the transmission queue 1377944b0429STrond Myklebust * @task: pointer to rpc_task 1378944b0429STrond Myklebust * 1379944b0429STrond Myklebust * Remove a task from the transmission queue 1380944b0429STrond Myklebust * Caller must hold xprt->queue_lock 1381944b0429STrond Myklebust */ 1382944b0429STrond Myklebust static void 1383944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(struct rpc_task *task) 1384944b0429STrond Myklebust { 1385918f3c1fSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1386918f3c1fSTrond Myklebust 1387918f3c1fSTrond Myklebust if (!test_and_clear_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 1388918f3c1fSTrond Myklebust return; 1389918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit)) { 1390918f3c1fSTrond Myklebust list_del(&req->rq_xmit); 1391918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit2)) { 1392918f3c1fSTrond Myklebust struct rpc_rqst *next = list_first_entry(&req->rq_xmit2, 1393918f3c1fSTrond Myklebust struct rpc_rqst, rq_xmit2); 1394918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1395918f3c1fSTrond Myklebust list_add_tail(&next->rq_xmit, &next->rq_xprt->xmit_queue); 1396918f3c1fSTrond Myklebust } 1397918f3c1fSTrond Myklebust } else 1398918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1399944b0429STrond Myklebust } 1400944b0429STrond Myklebust 1401944b0429STrond Myklebust /** 1402944b0429STrond Myklebust * xprt_request_dequeue_transmit - remove a task from the transmission queue 1403944b0429STrond Myklebust * @task: pointer to rpc_task 1404944b0429STrond Myklebust * 1405944b0429STrond Myklebust * Remove a task from the transmission queue 1406944b0429STrond Myklebust */ 1407944b0429STrond Myklebust static void 1408944b0429STrond Myklebust xprt_request_dequeue_transmit(struct rpc_task *task) 1409944b0429STrond Myklebust { 1410944b0429STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1411944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1412944b0429STrond Myklebust 1413944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 1414944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1415944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1416944b0429STrond Myklebust } 1417944b0429STrond Myklebust 14187f3a1d1eSTrond Myklebust /** 1419cc204d01STrond Myklebust * xprt_request_dequeue_xprt - remove a task from the transmit+receive queue 1420cc204d01STrond Myklebust * @task: pointer to rpc_task 1421cc204d01STrond Myklebust * 1422cc204d01STrond Myklebust * Remove a task from the transmit and receive queues, and ensure that 1423cc204d01STrond Myklebust * it is not pinned by the receive work item. 1424cc204d01STrond Myklebust */ 1425cc204d01STrond Myklebust void 1426cc204d01STrond Myklebust xprt_request_dequeue_xprt(struct rpc_task *task) 1427cc204d01STrond Myklebust { 1428cc204d01STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1429cc204d01STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1430cc204d01STrond Myklebust 1431cc204d01STrond Myklebust if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) || 1432cc204d01STrond Myklebust test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || 1433cc204d01STrond Myklebust xprt_is_pinned_rqst(req)) { 1434cc204d01STrond Myklebust spin_lock(&xprt->queue_lock); 1435cc204d01STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1436cc204d01STrond Myklebust xprt_request_dequeue_receive_locked(task); 1437cc204d01STrond Myklebust while (xprt_is_pinned_rqst(req)) { 1438cc204d01STrond Myklebust set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1439cc204d01STrond Myklebust spin_unlock(&xprt->queue_lock); 1440cc204d01STrond Myklebust xprt_wait_on_pinned_rqst(req); 1441cc204d01STrond Myklebust spin_lock(&xprt->queue_lock); 1442cc204d01STrond Myklebust clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1443cc204d01STrond Myklebust } 1444cc204d01STrond Myklebust spin_unlock(&xprt->queue_lock); 1445cc204d01STrond Myklebust } 1446cc204d01STrond Myklebust } 1447cc204d01STrond Myklebust 1448cc204d01STrond Myklebust /** 14499d96acbcSTrond Myklebust * xprt_request_prepare - prepare an encoded request for transport 14509d96acbcSTrond Myklebust * @req: pointer to rpc_rqst 14519d96acbcSTrond Myklebust * 14529d96acbcSTrond Myklebust * Calls into the transport layer to do whatever is needed to prepare 14539d96acbcSTrond Myklebust * the request for transmission or receive. 14549d96acbcSTrond Myklebust */ 14559d96acbcSTrond Myklebust void 14569d96acbcSTrond Myklebust xprt_request_prepare(struct rpc_rqst *req) 14579d96acbcSTrond Myklebust { 14589d96acbcSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 14599d96acbcSTrond Myklebust 14609d96acbcSTrond Myklebust if (xprt->ops->prepare_request) 14619d96acbcSTrond Myklebust xprt->ops->prepare_request(req); 14629d96acbcSTrond Myklebust } 14639d96acbcSTrond Myklebust 14649d96acbcSTrond Myklebust /** 1465762e4e67STrond Myklebust * xprt_request_need_retransmit - Test if a task needs retransmission 1466762e4e67STrond Myklebust * @task: pointer to rpc_task 1467762e4e67STrond Myklebust * 1468762e4e67STrond Myklebust * Test for whether a connection breakage requires the task to retransmit 1469762e4e67STrond Myklebust */ 1470762e4e67STrond Myklebust bool 1471762e4e67STrond Myklebust xprt_request_need_retransmit(struct rpc_task *task) 1472762e4e67STrond Myklebust { 1473762e4e67STrond Myklebust return xprt_request_retransmit_after_disconnect(task); 1474762e4e67STrond Myklebust } 1475762e4e67STrond Myklebust 1476762e4e67STrond Myklebust /** 14779903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 14789903cd1cSChuck Lever * @task: RPC task about to send a request 14799903cd1cSChuck Lever * 14801da177e4SLinus Torvalds */ 148190051ea7STrond Myklebust bool xprt_prepare_transmit(struct rpc_task *task) 14821da177e4SLinus Torvalds { 14831da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 14841da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 14851da177e4SLinus Torvalds 14865f2f6bd9STrond Myklebust if (!xprt_lock_write(xprt, task)) { 14879ce07ae5SChuck Lever trace_xprt_transmit_queued(xprt, task); 14889ce07ae5SChuck Lever 14895f2f6bd9STrond Myklebust /* Race breaker: someone may have transmitted us */ 1490944b0429STrond Myklebust if (!test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 14915f2f6bd9STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, 14925f2f6bd9STrond Myklebust task, 0); 14935f2f6bd9STrond Myklebust return false; 14945f2f6bd9STrond Myklebust 14958a19a0b6STrond Myklebust } 14965f2f6bd9STrond Myklebust return true; 14971da177e4SLinus Torvalds } 14981da177e4SLinus Torvalds 1499e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 15005e5ce5beSTrond Myklebust { 1501343952faSRahul Iyer xprt_release_write(task->tk_rqstp->rq_xprt, task); 15025e5ce5beSTrond Myklebust } 15035e5ce5beSTrond Myklebust 15049903cd1cSChuck Lever /** 150589f90fe1STrond Myklebust * xprt_request_transmit - send an RPC request on a transport 150689f90fe1STrond Myklebust * @req: pointer to request to transmit 150789f90fe1STrond Myklebust * @snd_task: RPC task that owns the transport lock 15089903cd1cSChuck Lever * 150989f90fe1STrond Myklebust * This performs the transmission of a single request. 151089f90fe1STrond Myklebust * Note that if the request is not the same as snd_task, then it 151189f90fe1STrond Myklebust * does need to be pinned. 151289f90fe1STrond Myklebust * Returns '0' on success. 15139903cd1cSChuck Lever */ 151489f90fe1STrond Myklebust static int 151589f90fe1STrond Myklebust xprt_request_transmit(struct rpc_rqst *req, struct rpc_task *snd_task) 15161da177e4SLinus Torvalds { 15171da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 151889f90fe1STrond Myklebust struct rpc_task *task = req->rq_task; 151990d91b0cSTrond Myklebust unsigned int connect_cookie; 1520dcbbeda8STrond Myklebust int is_retrans = RPC_WAS_SENT(task); 1521ff699ea8SChuck Lever int status; 15221da177e4SLinus Torvalds 1523edc81dcdSTrond Myklebust if (!req->rq_bytes_sent) { 152489f90fe1STrond Myklebust if (xprt_request_data_received(task)) { 152589f90fe1STrond Myklebust status = 0; 1526944b0429STrond Myklebust goto out_dequeue; 152789f90fe1STrond Myklebust } 15283021a5bbSTrond Myklebust /* Verify that our message lies in the RPCSEC_GSS window */ 1529edc81dcdSTrond Myklebust if (rpcauth_xmit_need_reencode(task)) { 153089f90fe1STrond Myklebust status = -EBADMSG; 1531944b0429STrond Myklebust goto out_dequeue; 15323021a5bbSTrond Myklebust } 1533ae67bd38STrond Myklebust if (RPC_SIGNALLED(task)) { 1534ae67bd38STrond Myklebust status = -ERESTARTSYS; 1535ae67bd38STrond Myklebust goto out_dequeue; 1536ae67bd38STrond Myklebust } 15371da177e4SLinus Torvalds } 15381da177e4SLinus Torvalds 1539dcbbeda8STrond Myklebust /* 1540dcbbeda8STrond Myklebust * Update req->rq_ntrans before transmitting to avoid races with 1541dcbbeda8STrond Myklebust * xprt_update_rtt(), which needs to know that it is recording a 1542dcbbeda8STrond Myklebust * reply to the first transmission. 1543dcbbeda8STrond Myklebust */ 1544dcbbeda8STrond Myklebust req->rq_ntrans++; 1545dcbbeda8STrond Myklebust 1546c509f15aSChuck Lever trace_rpc_xdr_sendto(task, &req->rq_snd_buf); 154790d91b0cSTrond Myklebust connect_cookie = xprt->connect_cookie; 1548adfa7144STrond Myklebust status = xprt->ops->send_request(req); 1549c8485e4dSTrond Myklebust if (status != 0) { 1550dcbbeda8STrond Myklebust req->rq_ntrans--; 15510c77668dSChuck Lever trace_xprt_transmit(req, status); 155289f90fe1STrond Myklebust return status; 1553c8485e4dSTrond Myklebust } 15547ebbbc6eSTrond Myklebust 1555dcbbeda8STrond Myklebust if (is_retrans) 1556dcbbeda8STrond Myklebust task->tk_client->cl_stats->rpcretrans++; 1557dcbbeda8STrond Myklebust 15584a068258SChuck Lever xprt_inject_disconnect(xprt); 1559c8485e4dSTrond Myklebust 1560468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 1561b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 1562262ca07dSChuck Lever 1563262ca07dSChuck Lever xprt->stat.sends++; 1564262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 1565262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 156615a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 156715a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 1568b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 156990d91b0cSTrond Myklebust 157090d91b0cSTrond Myklebust req->rq_connect_cookie = connect_cookie; 1571944b0429STrond Myklebust out_dequeue: 15720c77668dSChuck Lever trace_xprt_transmit(req, status); 1573944b0429STrond Myklebust xprt_request_dequeue_transmit(task); 157489f90fe1STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, task, status); 157589f90fe1STrond Myklebust return status; 157689f90fe1STrond Myklebust } 157789f90fe1STrond Myklebust 157889f90fe1STrond Myklebust /** 157989f90fe1STrond Myklebust * xprt_transmit - send an RPC request on a transport 158089f90fe1STrond Myklebust * @task: controlling RPC task 158189f90fe1STrond Myklebust * 158289f90fe1STrond Myklebust * Attempts to drain the transmit queue. On exit, either the transport 158389f90fe1STrond Myklebust * signalled an error that needs to be handled before transmission can 158489f90fe1STrond Myklebust * resume, or @task finished transmitting, and detected that it already 158589f90fe1STrond Myklebust * received a reply. 158689f90fe1STrond Myklebust */ 158789f90fe1STrond Myklebust void 158889f90fe1STrond Myklebust xprt_transmit(struct rpc_task *task) 158989f90fe1STrond Myklebust { 159089f90fe1STrond Myklebust struct rpc_rqst *next, *req = task->tk_rqstp; 159189f90fe1STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 15926f9f1728SChuck Lever int counter, status; 159389f90fe1STrond Myklebust 159489f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 15956f9f1728SChuck Lever counter = 0; 159689f90fe1STrond Myklebust while (!list_empty(&xprt->xmit_queue)) { 15976f9f1728SChuck Lever if (++counter == 20) 15986f9f1728SChuck Lever break; 159989f90fe1STrond Myklebust next = list_first_entry(&xprt->xmit_queue, 160089f90fe1STrond Myklebust struct rpc_rqst, rq_xmit); 160189f90fe1STrond Myklebust xprt_pin_rqst(next); 160289f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 160389f90fe1STrond Myklebust status = xprt_request_transmit(next, task); 160489f90fe1STrond Myklebust if (status == -EBADMSG && next != req) 160589f90fe1STrond Myklebust status = 0; 160689f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 160789f90fe1STrond Myklebust xprt_unpin_rqst(next); 160889f90fe1STrond Myklebust if (status == 0) { 160989f90fe1STrond Myklebust if (!xprt_request_data_received(task) || 161089f90fe1STrond Myklebust test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 161189f90fe1STrond Myklebust continue; 1612c544577dSTrond Myklebust } else if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 161389f90fe1STrond Myklebust task->tk_status = status; 161489f90fe1STrond Myklebust break; 161589f90fe1STrond Myklebust } 161689f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 16171da177e4SLinus Torvalds } 16181da177e4SLinus Torvalds 1619ba60eb25STrond Myklebust static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) 1620ba60eb25STrond Myklebust { 1621ba60eb25STrond Myklebust set_bit(XPRT_CONGESTED, &xprt->state); 1622ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1623ba60eb25STrond Myklebust } 1624ba60eb25STrond Myklebust 1625ba60eb25STrond Myklebust static void xprt_wake_up_backlog(struct rpc_xprt *xprt) 1626ba60eb25STrond Myklebust { 1627ba60eb25STrond Myklebust if (rpc_wake_up_next(&xprt->backlog) == NULL) 1628ba60eb25STrond Myklebust clear_bit(XPRT_CONGESTED, &xprt->state); 1629ba60eb25STrond Myklebust } 1630ba60eb25STrond Myklebust 1631ba60eb25STrond Myklebust static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) 1632ba60eb25STrond Myklebust { 1633ba60eb25STrond Myklebust bool ret = false; 1634ba60eb25STrond Myklebust 1635ba60eb25STrond Myklebust if (!test_bit(XPRT_CONGESTED, &xprt->state)) 1636ba60eb25STrond Myklebust goto out; 1637ba60eb25STrond Myklebust spin_lock(&xprt->reserve_lock); 1638ba60eb25STrond Myklebust if (test_bit(XPRT_CONGESTED, &xprt->state)) { 1639ba60eb25STrond Myklebust rpc_sleep_on(&xprt->backlog, task, NULL); 1640ba60eb25STrond Myklebust ret = true; 1641ba60eb25STrond Myklebust } 1642ba60eb25STrond Myklebust spin_unlock(&xprt->reserve_lock); 1643ba60eb25STrond Myklebust out: 1644ba60eb25STrond Myklebust return ret; 1645ba60eb25STrond Myklebust } 1646ba60eb25STrond Myklebust 164792ea011fSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt) 1648d9ba131dSTrond Myklebust { 1649d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 1650d9ba131dSTrond Myklebust 1651ff699ea8SChuck Lever if (xprt->num_reqs >= xprt->max_reqs) 1652d9ba131dSTrond Myklebust goto out; 1653ff699ea8SChuck Lever ++xprt->num_reqs; 165492ea011fSTrond Myklebust spin_unlock(&xprt->reserve_lock); 165592ea011fSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_NOFS); 165692ea011fSTrond Myklebust spin_lock(&xprt->reserve_lock); 1657d9ba131dSTrond Myklebust if (req != NULL) 1658d9ba131dSTrond Myklebust goto out; 1659ff699ea8SChuck Lever --xprt->num_reqs; 1660d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 1661d9ba131dSTrond Myklebust out: 1662d9ba131dSTrond Myklebust return req; 1663d9ba131dSTrond Myklebust } 1664d9ba131dSTrond Myklebust 1665d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1666d9ba131dSTrond Myklebust { 1667ff699ea8SChuck Lever if (xprt->num_reqs > xprt->min_reqs) { 1668ff699ea8SChuck Lever --xprt->num_reqs; 1669d9ba131dSTrond Myklebust kfree(req); 1670d9ba131dSTrond Myklebust return true; 1671d9ba131dSTrond Myklebust } 1672d9ba131dSTrond Myklebust return false; 1673d9ba131dSTrond Myklebust } 1674d9ba131dSTrond Myklebust 1675f39c1bfbSTrond Myklebust void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 16761da177e4SLinus Torvalds { 1677d9ba131dSTrond Myklebust struct rpc_rqst *req; 16781da177e4SLinus Torvalds 1679f39c1bfbSTrond Myklebust spin_lock(&xprt->reserve_lock); 16801da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 1681d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 1682d9ba131dSTrond Myklebust list_del(&req->rq_list); 1683d9ba131dSTrond Myklebust goto out_init_req; 1684d9ba131dSTrond Myklebust } 168592ea011fSTrond Myklebust req = xprt_dynamic_alloc_slot(xprt); 1686d9ba131dSTrond Myklebust if (!IS_ERR(req)) 1687d9ba131dSTrond Myklebust goto out_init_req; 1688d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 1689d9ba131dSTrond Myklebust case -ENOMEM: 1690d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 1691d9ba131dSTrond Myklebust "failed! Retrying\n"); 16921afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 1693d9ba131dSTrond Myklebust break; 1694d9ba131dSTrond Myklebust case -EAGAIN: 1695ba60eb25STrond Myklebust xprt_add_backlog(xprt, task); 1696d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 1697df561f66SGustavo A. R. Silva fallthrough; 16981afeaf5cSTrond Myklebust default: 1699d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 17001afeaf5cSTrond Myklebust } 1701f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 1702d9ba131dSTrond Myklebust return; 1703d9ba131dSTrond Myklebust out_init_req: 1704ff699ea8SChuck Lever xprt->stat.max_slots = max_t(unsigned int, xprt->stat.max_slots, 1705ff699ea8SChuck Lever xprt->num_reqs); 170637ac86c3SChuck Lever spin_unlock(&xprt->reserve_lock); 170737ac86c3SChuck Lever 1708d9ba131dSTrond Myklebust task->tk_status = 0; 17091da177e4SLinus Torvalds task->tk_rqstp = req; 17101da177e4SLinus Torvalds } 1711f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_alloc_slot); 1712f39c1bfbSTrond Myklebust 1713a9cde23aSChuck Lever void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1714ee5ebe85STrond Myklebust { 1715ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1716c25573b5STrond Myklebust if (!xprt_dynamic_free_slot(xprt, req)) { 1717c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1718ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1719c25573b5STrond Myklebust } 1720ba60eb25STrond Myklebust xprt_wake_up_backlog(xprt); 1721ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1722ee5ebe85STrond Myklebust } 1723a9cde23aSChuck Lever EXPORT_SYMBOL_GPL(xprt_free_slot); 1724ee5ebe85STrond Myklebust 172521de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 172621de0a95STrond Myklebust { 172721de0a95STrond Myklebust struct rpc_rqst *req; 172821de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 172921de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 173021de0a95STrond Myklebust list_del(&req->rq_list); 173121de0a95STrond Myklebust kfree(req); 173221de0a95STrond Myklebust } 173321de0a95STrond Myklebust } 173421de0a95STrond Myklebust 1735d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1736d9ba131dSTrond Myklebust unsigned int num_prealloc, 1737d9ba131dSTrond Myklebust unsigned int max_alloc) 1738bd1722d4SPavel Emelyanov { 1739bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 174021de0a95STrond Myklebust struct rpc_rqst *req; 174121de0a95STrond Myklebust int i; 1742bd1722d4SPavel Emelyanov 1743bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1744bd1722d4SPavel Emelyanov if (xprt == NULL) 1745bd1722d4SPavel Emelyanov goto out; 1746bd1722d4SPavel Emelyanov 174721de0a95STrond Myklebust xprt_init(xprt, net); 174821de0a95STrond Myklebust 174921de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 175021de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 175121de0a95STrond Myklebust if (!req) 17528313164cSwangweidong goto out_free; 175321de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 175421de0a95STrond Myklebust } 1755d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1756d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1757d9ba131dSTrond Myklebust else 175821de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1759d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1760ff699ea8SChuck Lever xprt->num_reqs = num_prealloc; 1761bd1722d4SPavel Emelyanov 1762bd1722d4SPavel Emelyanov return xprt; 1763bd1722d4SPavel Emelyanov 1764bd1722d4SPavel Emelyanov out_free: 176521de0a95STrond Myklebust xprt_free(xprt); 1766bd1722d4SPavel Emelyanov out: 1767bd1722d4SPavel Emelyanov return NULL; 1768bd1722d4SPavel Emelyanov } 1769bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1770bd1722d4SPavel Emelyanov 1771e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1772e204e621SPavel Emelyanov { 177337aa2133SPavel Emelyanov put_net(xprt->xprt_net); 177421de0a95STrond Myklebust xprt_free_all_slots(xprt); 1775fda1bfefSTrond Myklebust kfree_rcu(xprt, rcu); 1776e204e621SPavel Emelyanov } 1777e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1778e204e621SPavel Emelyanov 1779902c5887STrond Myklebust static void 1780902c5887STrond Myklebust xprt_init_connect_cookie(struct rpc_rqst *req, struct rpc_xprt *xprt) 1781902c5887STrond Myklebust { 1782902c5887STrond Myklebust req->rq_connect_cookie = xprt_connect_cookie(xprt) - 1; 1783902c5887STrond Myklebust } 1784902c5887STrond Myklebust 17859dc6edcfSTrond Myklebust static __be32 17869dc6edcfSTrond Myklebust xprt_alloc_xid(struct rpc_xprt *xprt) 17879dc6edcfSTrond Myklebust { 17889dc6edcfSTrond Myklebust __be32 xid; 17899dc6edcfSTrond Myklebust 17909dc6edcfSTrond Myklebust spin_lock(&xprt->reserve_lock); 17919dc6edcfSTrond Myklebust xid = (__force __be32)xprt->xid++; 17929dc6edcfSTrond Myklebust spin_unlock(&xprt->reserve_lock); 17939dc6edcfSTrond Myklebust return xid; 17949dc6edcfSTrond Myklebust } 17959dc6edcfSTrond Myklebust 17969dc6edcfSTrond Myklebust static void 17979dc6edcfSTrond Myklebust xprt_init_xid(struct rpc_xprt *xprt) 17989dc6edcfSTrond Myklebust { 17999dc6edcfSTrond Myklebust xprt->xid = prandom_u32(); 18009dc6edcfSTrond Myklebust } 18019dc6edcfSTrond Myklebust 18029dc6edcfSTrond Myklebust static void 18039dc6edcfSTrond Myklebust xprt_request_init(struct rpc_task *task) 18049dc6edcfSTrond Myklebust { 18059dc6edcfSTrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 18069dc6edcfSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 18079dc6edcfSTrond Myklebust 18089dc6edcfSTrond Myklebust req->rq_task = task; 18099dc6edcfSTrond Myklebust req->rq_xprt = xprt; 18109dc6edcfSTrond Myklebust req->rq_buffer = NULL; 18119dc6edcfSTrond Myklebust req->rq_xid = xprt_alloc_xid(xprt); 1812902c5887STrond Myklebust xprt_init_connect_cookie(req, xprt); 18139dc6edcfSTrond Myklebust req->rq_snd_buf.len = 0; 18149dc6edcfSTrond Myklebust req->rq_snd_buf.buflen = 0; 18159dc6edcfSTrond Myklebust req->rq_rcv_buf.len = 0; 18169dc6edcfSTrond Myklebust req->rq_rcv_buf.buflen = 0; 181771700bb9STrond Myklebust req->rq_snd_buf.bvec = NULL; 181871700bb9STrond Myklebust req->rq_rcv_buf.bvec = NULL; 18199dc6edcfSTrond Myklebust req->rq_release_snd_buf = NULL; 1820da953063STrond Myklebust xprt_init_majortimeo(task, req); 182109d2ba0cSChuck Lever 182209d2ba0cSChuck Lever trace_xprt_reserve(req); 18239dc6edcfSTrond Myklebust } 18249dc6edcfSTrond Myklebust 18259dc6edcfSTrond Myklebust static void 18269dc6edcfSTrond Myklebust xprt_do_reserve(struct rpc_xprt *xprt, struct rpc_task *task) 18279dc6edcfSTrond Myklebust { 18289dc6edcfSTrond Myklebust xprt->ops->alloc_slot(xprt, task); 18299dc6edcfSTrond Myklebust if (task->tk_rqstp != NULL) 18309dc6edcfSTrond Myklebust xprt_request_init(task); 18319dc6edcfSTrond Myklebust } 18329dc6edcfSTrond Myklebust 18339903cd1cSChuck Lever /** 18349903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 18359903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 18369903cd1cSChuck Lever * 1837ba60eb25STrond Myklebust * If the transport is marked as being congested, or if no more 1838ba60eb25STrond Myklebust * slots are available, place the task on the transport's 18399903cd1cSChuck Lever * backlog queue. 18409903cd1cSChuck Lever */ 18419903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 18421da177e4SLinus Torvalds { 1843fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 18441da177e4SLinus Torvalds 184543cedbf0STrond Myklebust task->tk_status = 0; 184643cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 184743cedbf0STrond Myklebust return; 184843cedbf0STrond Myklebust 184943cedbf0STrond Myklebust task->tk_status = -EAGAIN; 1850ba60eb25STrond Myklebust if (!xprt_throttle_congested(xprt, task)) 18519dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 1852ba60eb25STrond Myklebust } 1853ba60eb25STrond Myklebust 1854ba60eb25STrond Myklebust /** 1855ba60eb25STrond Myklebust * xprt_retry_reserve - allocate an RPC request slot 1856ba60eb25STrond Myklebust * @task: RPC task requesting a slot allocation 1857ba60eb25STrond Myklebust * 1858ba60eb25STrond Myklebust * If no more slots are available, place the task on the transport's 1859ba60eb25STrond Myklebust * backlog queue. 1860ba60eb25STrond Myklebust * Note that the only difference with xprt_reserve is that we now 1861ba60eb25STrond Myklebust * ignore the value of the XPRT_CONGESTED flag. 1862ba60eb25STrond Myklebust */ 1863ba60eb25STrond Myklebust void xprt_retry_reserve(struct rpc_task *task) 1864ba60eb25STrond Myklebust { 1865fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 1866ba60eb25STrond Myklebust 1867ba60eb25STrond Myklebust task->tk_status = 0; 1868ba60eb25STrond Myklebust if (task->tk_rqstp != NULL) 1869ba60eb25STrond Myklebust return; 1870ba60eb25STrond Myklebust 1871ba60eb25STrond Myklebust task->tk_status = -EAGAIN; 18729dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 18731da177e4SLinus Torvalds } 18741da177e4SLinus Torvalds 18759903cd1cSChuck Lever /** 18769903cd1cSChuck Lever * xprt_release - release an RPC request slot 18779903cd1cSChuck Lever * @task: task which is finished with the slot 18789903cd1cSChuck Lever * 18791da177e4SLinus Torvalds */ 18809903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 18811da177e4SLinus Torvalds { 188255ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 188387ed5003STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 18841da177e4SLinus Torvalds 188587ed5003STrond Myklebust if (req == NULL) { 188687ed5003STrond Myklebust if (task->tk_client) { 1887fb43d172STrond Myklebust xprt = task->tk_xprt; 188887ed5003STrond Myklebust xprt_release_write(xprt, task); 188987ed5003STrond Myklebust } 18901da177e4SLinus Torvalds return; 189187ed5003STrond Myklebust } 189255ae1aabSRicardo Labiaga 189355ae1aabSRicardo Labiaga xprt = req->rq_xprt; 1894cc204d01STrond Myklebust xprt_request_dequeue_xprt(task); 1895b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 189649e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1897a58dd398SChuck Lever if (xprt->ops->release_request) 1898a58dd398SChuck Lever xprt->ops->release_request(task); 1899ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 1900b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 1901ee5ebe85STrond Myklebust if (req->rq_buffer) 19023435c74aSChuck Lever xprt->ops->buf_free(task); 19034a068258SChuck Lever xprt_inject_disconnect(xprt); 19049d96acbcSTrond Myklebust xdr_free_bvec(&req->rq_rcv_buf); 19050472e476STrond Myklebust xdr_free_bvec(&req->rq_snd_buf); 1906a17c2153STrond Myklebust if (req->rq_cred != NULL) 1907a17c2153STrond Myklebust put_rpccred(req->rq_cred); 19081da177e4SLinus Torvalds task->tk_rqstp = NULL; 1909ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1910ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 191155ae1aabSRicardo Labiaga 1912ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1913a9cde23aSChuck Lever xprt->ops->free_slot(xprt, req); 1914ee5ebe85STrond Myklebust else 1915c9acb42eSTrond Myklebust xprt_free_bc_request(req); 19161da177e4SLinus Torvalds } 19171da177e4SLinus Torvalds 1918902c5887STrond Myklebust #ifdef CONFIG_SUNRPC_BACKCHANNEL 1919902c5887STrond Myklebust void 1920902c5887STrond Myklebust xprt_init_bc_request(struct rpc_rqst *req, struct rpc_task *task) 1921902c5887STrond Myklebust { 1922902c5887STrond Myklebust struct xdr_buf *xbufp = &req->rq_snd_buf; 1923902c5887STrond Myklebust 1924902c5887STrond Myklebust task->tk_rqstp = req; 1925902c5887STrond Myklebust req->rq_task = task; 1926902c5887STrond Myklebust xprt_init_connect_cookie(req, req->rq_xprt); 1927902c5887STrond Myklebust /* 1928902c5887STrond Myklebust * Set up the xdr_buf length. 1929902c5887STrond Myklebust * This also indicates that the buffer is XDR encoded already. 1930902c5887STrond Myklebust */ 1931902c5887STrond Myklebust xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1932902c5887STrond Myklebust xbufp->tail[0].iov_len; 1933902c5887STrond Myklebust } 1934902c5887STrond Myklebust #endif 1935902c5887STrond Myklebust 193621de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1937c2866763SChuck Lever { 193830c5116bSTrond Myklebust kref_init(&xprt->kref); 1939c2866763SChuck Lever 1940c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1941c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 194275c84151STrond Myklebust spin_lock_init(&xprt->queue_lock); 1943c2866763SChuck Lever 1944c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 194595f7691dSTrond Myklebust xprt->recv_queue = RB_ROOT; 1946944b0429STrond Myklebust INIT_LIST_HEAD(&xprt->xmit_queue); 19479e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1948f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 1949f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 19509e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 195180b14d5eSTrond Myklebust INIT_LIST_HEAD(&xprt->xprt_switch); 1952f9acac1aSRicardo Labiaga 1953c2866763SChuck Lever xprt->last_used = jiffies; 1954c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 1955a509050bSChuck Lever xprt->bind_index = 0; 1956c2866763SChuck Lever 1957c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 1958c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 195979c99152STrond Myklebust rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 1960c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 1961c2866763SChuck Lever 1962c2866763SChuck Lever xprt_init_xid(xprt); 1963c2866763SChuck Lever 196421de0a95STrond Myklebust xprt->xprt_net = get_net(net); 19658d9266ffSTrond Myklebust } 19668d9266ffSTrond Myklebust 19678d9266ffSTrond Myklebust /** 19688d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 19698d9266ffSTrond Myklebust * @args: rpc transport creation arguments 19708d9266ffSTrond Myklebust * 19718d9266ffSTrond Myklebust */ 19728d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 19738d9266ffSTrond Myklebust { 19748d9266ffSTrond Myklebust struct rpc_xprt *xprt; 19759bccd264STrond Myklebust const struct xprt_class *t; 19768d9266ffSTrond Myklebust 19779bccd264STrond Myklebust t = xprt_class_find_by_ident(args->ident); 19789bccd264STrond Myklebust if (!t) { 19793c45ddf8SChuck Lever dprintk("RPC: transport (%d) not supported\n", args->ident); 19808d9266ffSTrond Myklebust return ERR_PTR(-EIO); 19819bccd264STrond Myklebust } 19828d9266ffSTrond Myklebust 19838d9266ffSTrond Myklebust xprt = t->setup(args); 19849bccd264STrond Myklebust xprt_class_release(t); 19859bccd264STrond Myklebust 1986911813d7SChuck Lever if (IS_ERR(xprt)) 198721de0a95STrond Myklebust goto out; 198833d90ac0SJ. Bruce Fields if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) 198933d90ac0SJ. Bruce Fields xprt->idle_timeout = 0; 199021de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 199121de0a95STrond Myklebust if (xprt_has_timer(xprt)) 1992502980e8SAnna Schumaker timer_setup(&xprt->timer, xprt_init_autodisconnect, 0); 199321de0a95STrond Myklebust else 1994ff861c4dSKees Cook timer_setup(&xprt->timer, NULL, 0); 19954e0038b6STrond Myklebust 19964e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 19974e0038b6STrond Myklebust xprt_destroy(xprt); 19984e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 19994e0038b6STrond Myklebust } 20004e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 20014e0038b6STrond Myklebust if (xprt->servername == NULL) { 20024e0038b6STrond Myklebust xprt_destroy(xprt); 20034e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 20044e0038b6STrond Myklebust } 20054e0038b6STrond Myklebust 20063f940098SJeff Layton rpc_xprt_debugfs_register(xprt); 2007388f0c77SJeff Layton 2008911813d7SChuck Lever trace_xprt_create(xprt); 200921de0a95STrond Myklebust out: 2010c2866763SChuck Lever return xprt; 2011c2866763SChuck Lever } 2012c2866763SChuck Lever 2013528fd354STrond Myklebust static void xprt_destroy_cb(struct work_struct *work) 2014528fd354STrond Myklebust { 2015528fd354STrond Myklebust struct rpc_xprt *xprt = 2016528fd354STrond Myklebust container_of(work, struct rpc_xprt, task_cleanup); 2017528fd354STrond Myklebust 2018911813d7SChuck Lever trace_xprt_destroy(xprt); 2019911813d7SChuck Lever 2020528fd354STrond Myklebust rpc_xprt_debugfs_unregister(xprt); 2021528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 2022528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 2023528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 2024528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 2025528fd354STrond Myklebust kfree(xprt->servername); 2026528fd354STrond Myklebust /* 2027669996adSTrond Myklebust * Destroy any existing back channel 2028669996adSTrond Myklebust */ 2029669996adSTrond Myklebust xprt_destroy_backchannel(xprt, UINT_MAX); 2030669996adSTrond Myklebust 2031669996adSTrond Myklebust /* 2032528fd354STrond Myklebust * Tear down transport state and free the rpc_xprt 2033528fd354STrond Myklebust */ 2034528fd354STrond Myklebust xprt->ops->destroy(xprt); 2035528fd354STrond Myklebust } 2036528fd354STrond Myklebust 20379903cd1cSChuck Lever /** 20389903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 2039a8de240aSTrond Myklebust * @xprt: transport to destroy 20409903cd1cSChuck Lever * 20411da177e4SLinus Torvalds */ 2042a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 20431da177e4SLinus Torvalds { 2044528fd354STrond Myklebust /* 2045528fd354STrond Myklebust * Exclude transport connect/disconnect handlers and autoclose 2046528fd354STrond Myklebust */ 204779234c3dSTrond Myklebust wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); 204879234c3dSTrond Myklebust 20490065db32STrond Myklebust del_timer_sync(&xprt->timer); 2050c8541ecdSChuck Lever 2051c8541ecdSChuck Lever /* 2052528fd354STrond Myklebust * Destroy sockets etc from the system workqueue so they can 2053528fd354STrond Myklebust * safely flush receive work running on rpciod. 2054c8541ecdSChuck Lever */ 2055528fd354STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_destroy_cb); 2056528fd354STrond Myklebust schedule_work(&xprt->task_cleanup); 20576b6ca86bSTrond Myklebust } 20581da177e4SLinus Torvalds 205930c5116bSTrond Myklebust static void xprt_destroy_kref(struct kref *kref) 206030c5116bSTrond Myklebust { 206130c5116bSTrond Myklebust xprt_destroy(container_of(kref, struct rpc_xprt, kref)); 206230c5116bSTrond Myklebust } 206330c5116bSTrond Myklebust 206430c5116bSTrond Myklebust /** 206530c5116bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 206630c5116bSTrond Myklebust * @xprt: pointer to the transport 206730c5116bSTrond Myklebust * 206830c5116bSTrond Myklebust */ 206930c5116bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 207030c5116bSTrond Myklebust { 207130c5116bSTrond Myklebust if (xprt != NULL && kref_get_unless_zero(&xprt->kref)) 207230c5116bSTrond Myklebust return xprt; 207330c5116bSTrond Myklebust return NULL; 207430c5116bSTrond Myklebust } 207530c5116bSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_get); 207630c5116bSTrond Myklebust 20776b6ca86bSTrond Myklebust /** 20786b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 20796b6ca86bSTrond Myklebust * @xprt: pointer to the transport 20806b6ca86bSTrond Myklebust * 20816b6ca86bSTrond Myklebust */ 20826b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 20836b6ca86bSTrond Myklebust { 208430c5116bSTrond Myklebust if (xprt != NULL) 208530c5116bSTrond Myklebust kref_put(&xprt->kref, xprt_destroy_kref); 20866b6ca86bSTrond Myklebust } 20875d252f90SChuck Lever EXPORT_SYMBOL_GPL(xprt_put); 2088