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" 58587bc725SOlga Kornievskaia #include "sysfs.h" 59*a4ae3081SChuck Lever #include "fail.h" 6055ae1aabSRicardo Labiaga 611da177e4SLinus Torvalds /* 621da177e4SLinus Torvalds * Local variables 631da177e4SLinus Torvalds */ 641da177e4SLinus Torvalds 65f895b252SJeff Layton #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 661da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_XPRT 671da177e4SLinus Torvalds #endif 681da177e4SLinus Torvalds 691da177e4SLinus Torvalds /* 701da177e4SLinus Torvalds * Local functions 711da177e4SLinus Torvalds */ 7221de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net); 7337ac86c3SChuck Lever static __be32 xprt_alloc_xid(struct rpc_xprt *xprt); 744e0038b6STrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt); 75e877a88dSNeilBrown static void xprt_request_init(struct rpc_task *task); 761da177e4SLinus Torvalds 775ba03e82SJiri Slaby static DEFINE_SPINLOCK(xprt_list_lock); 7881c098afS\"Talpey, Thomas\ static LIST_HEAD(xprt_list); 7981c098afS\"Talpey, Thomas\ 809e910bffSTrond Myklebust static unsigned long xprt_request_timeout(const struct rpc_rqst *req) 819e910bffSTrond Myklebust { 829e910bffSTrond Myklebust unsigned long timeout = jiffies + req->rq_timeout; 839e910bffSTrond Myklebust 849e910bffSTrond Myklebust if (time_before(timeout, req->rq_majortimeo)) 859e910bffSTrond Myklebust return timeout; 869e910bffSTrond Myklebust return req->rq_majortimeo; 879e910bffSTrond Myklebust } 889e910bffSTrond Myklebust 8912a80469SChuck Lever /** 9081c098afS\"Talpey, Thomas\ * xprt_register_transport - register a transport implementation 9181c098afS\"Talpey, Thomas\ * @transport: transport to register 9281c098afS\"Talpey, Thomas\ * 9381c098afS\"Talpey, Thomas\ * If a transport implementation is loaded as a kernel module, it can 9481c098afS\"Talpey, Thomas\ * call this interface to make itself known to the RPC client. 9581c098afS\"Talpey, Thomas\ * 9681c098afS\"Talpey, Thomas\ * Returns: 9781c098afS\"Talpey, Thomas\ * 0: transport successfully registered 9881c098afS\"Talpey, Thomas\ * -EEXIST: transport already registered 9981c098afS\"Talpey, Thomas\ * -EINVAL: transport module being unloaded 10081c098afS\"Talpey, Thomas\ */ 10181c098afS\"Talpey, Thomas\ int xprt_register_transport(struct xprt_class *transport) 10281c098afS\"Talpey, Thomas\ { 10381c098afS\"Talpey, Thomas\ struct xprt_class *t; 10481c098afS\"Talpey, Thomas\ int result; 10581c098afS\"Talpey, Thomas\ 10681c098afS\"Talpey, Thomas\ result = -EEXIST; 10781c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 10881c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 10981c098afS\"Talpey, Thomas\ /* don't register the same transport class twice */ 1104fa016ebS\"Talpey, Thomas\ if (t->ident == transport->ident) 11181c098afS\"Talpey, Thomas\ goto out; 11281c098afS\"Talpey, Thomas\ } 11381c098afS\"Talpey, Thomas\ 11481c098afS\"Talpey, Thomas\ list_add_tail(&transport->list, &xprt_list); 11581c098afS\"Talpey, Thomas\ printk(KERN_INFO "RPC: Registered %s transport module.\n", 11681c098afS\"Talpey, Thomas\ transport->name); 11781c098afS\"Talpey, Thomas\ result = 0; 11881c098afS\"Talpey, Thomas\ 11981c098afS\"Talpey, Thomas\ out: 12081c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 12181c098afS\"Talpey, Thomas\ return result; 12281c098afS\"Talpey, Thomas\ } 12381c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_register_transport); 12481c098afS\"Talpey, Thomas\ 12581c098afS\"Talpey, Thomas\ /** 12681c098afS\"Talpey, Thomas\ * xprt_unregister_transport - unregister a transport implementation 12765b6e42cSRandy Dunlap * @transport: transport to unregister 12881c098afS\"Talpey, Thomas\ * 12981c098afS\"Talpey, Thomas\ * Returns: 13081c098afS\"Talpey, Thomas\ * 0: transport successfully unregistered 13181c098afS\"Talpey, Thomas\ * -ENOENT: transport never registered 13281c098afS\"Talpey, Thomas\ */ 13381c098afS\"Talpey, Thomas\ int xprt_unregister_transport(struct xprt_class *transport) 13481c098afS\"Talpey, Thomas\ { 13581c098afS\"Talpey, Thomas\ struct xprt_class *t; 13681c098afS\"Talpey, Thomas\ int result; 13781c098afS\"Talpey, Thomas\ 13881c098afS\"Talpey, Thomas\ result = 0; 13981c098afS\"Talpey, Thomas\ spin_lock(&xprt_list_lock); 14081c098afS\"Talpey, Thomas\ list_for_each_entry(t, &xprt_list, list) { 14181c098afS\"Talpey, Thomas\ if (t == transport) { 14281c098afS\"Talpey, Thomas\ printk(KERN_INFO 14381c098afS\"Talpey, Thomas\ "RPC: Unregistered %s transport module.\n", 14481c098afS\"Talpey, Thomas\ transport->name); 14581c098afS\"Talpey, Thomas\ list_del_init(&transport->list); 14681c098afS\"Talpey, Thomas\ goto out; 14781c098afS\"Talpey, Thomas\ } 14881c098afS\"Talpey, Thomas\ } 14981c098afS\"Talpey, Thomas\ result = -ENOENT; 15081c098afS\"Talpey, Thomas\ 15181c098afS\"Talpey, Thomas\ out: 15281c098afS\"Talpey, Thomas\ spin_unlock(&xprt_list_lock); 15381c098afS\"Talpey, Thomas\ return result; 15481c098afS\"Talpey, Thomas\ } 15581c098afS\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_unregister_transport); 15681c098afS\"Talpey, Thomas\ 157d5aa6b22STrond Myklebust static void 158d5aa6b22STrond Myklebust xprt_class_release(const struct xprt_class *t) 159d5aa6b22STrond Myklebust { 160d5aa6b22STrond Myklebust module_put(t->owner); 161d5aa6b22STrond Myklebust } 162d5aa6b22STrond Myklebust 163d5aa6b22STrond Myklebust static const struct xprt_class * 1649bccd264STrond Myklebust xprt_class_find_by_ident_locked(int ident) 1659bccd264STrond Myklebust { 1669bccd264STrond Myklebust const struct xprt_class *t; 1679bccd264STrond Myklebust 1689bccd264STrond Myklebust list_for_each_entry(t, &xprt_list, list) { 1699bccd264STrond Myklebust if (t->ident != ident) 1709bccd264STrond Myklebust continue; 1719bccd264STrond Myklebust if (!try_module_get(t->owner)) 1729bccd264STrond Myklebust continue; 1739bccd264STrond Myklebust return t; 1749bccd264STrond Myklebust } 1759bccd264STrond Myklebust return NULL; 1769bccd264STrond Myklebust } 1779bccd264STrond Myklebust 1789bccd264STrond Myklebust static const struct xprt_class * 1799bccd264STrond Myklebust xprt_class_find_by_ident(int ident) 1809bccd264STrond Myklebust { 1819bccd264STrond Myklebust const struct xprt_class *t; 1829bccd264STrond Myklebust 1839bccd264STrond Myklebust spin_lock(&xprt_list_lock); 1849bccd264STrond Myklebust t = xprt_class_find_by_ident_locked(ident); 1859bccd264STrond Myklebust spin_unlock(&xprt_list_lock); 1869bccd264STrond Myklebust return t; 1879bccd264STrond Myklebust } 1889bccd264STrond Myklebust 1899bccd264STrond Myklebust static const struct xprt_class * 190d5aa6b22STrond Myklebust xprt_class_find_by_netid_locked(const char *netid) 191d5aa6b22STrond Myklebust { 192d5aa6b22STrond Myklebust const struct xprt_class *t; 193d5aa6b22STrond Myklebust unsigned int i; 194d5aa6b22STrond Myklebust 195d5aa6b22STrond Myklebust list_for_each_entry(t, &xprt_list, list) { 196d5aa6b22STrond Myklebust for (i = 0; t->netid[i][0] != '\0'; i++) { 197d5aa6b22STrond Myklebust if (strcmp(t->netid[i], netid) != 0) 198d5aa6b22STrond Myklebust continue; 199d5aa6b22STrond Myklebust if (!try_module_get(t->owner)) 200d5aa6b22STrond Myklebust continue; 201d5aa6b22STrond Myklebust return t; 202d5aa6b22STrond Myklebust } 203d5aa6b22STrond Myklebust } 204d5aa6b22STrond Myklebust return NULL; 205d5aa6b22STrond Myklebust } 206d5aa6b22STrond Myklebust 207d5aa6b22STrond Myklebust static const struct xprt_class * 208d5aa6b22STrond Myklebust xprt_class_find_by_netid(const char *netid) 209d5aa6b22STrond Myklebust { 210d5aa6b22STrond Myklebust const struct xprt_class *t; 211d5aa6b22STrond Myklebust 212d5aa6b22STrond Myklebust spin_lock(&xprt_list_lock); 213d5aa6b22STrond Myklebust t = xprt_class_find_by_netid_locked(netid); 214d5aa6b22STrond Myklebust if (!t) { 215d5aa6b22STrond Myklebust spin_unlock(&xprt_list_lock); 216d5aa6b22STrond Myklebust request_module("rpc%s", netid); 217d5aa6b22STrond Myklebust spin_lock(&xprt_list_lock); 218d5aa6b22STrond Myklebust t = xprt_class_find_by_netid_locked(netid); 219d5aa6b22STrond Myklebust } 220d5aa6b22STrond Myklebust spin_unlock(&xprt_list_lock); 221d5aa6b22STrond Myklebust return t; 222d5aa6b22STrond Myklebust } 223d5aa6b22STrond Myklebust 22481c098afS\"Talpey, Thomas\ /** 2251fc5f131STrond Myklebust * xprt_find_transport_ident - convert a netid into a transport identifier 2261fc5f131STrond Myklebust * @netid: transport to load 2271fc5f131STrond Myklebust * 2281fc5f131STrond Myklebust * Returns: 2291fc5f131STrond Myklebust * > 0: transport identifier 2301fc5f131STrond Myklebust * -ENOENT: transport module not available 2311fc5f131STrond Myklebust */ 2321fc5f131STrond Myklebust int xprt_find_transport_ident(const char *netid) 2331fc5f131STrond Myklebust { 2341fc5f131STrond Myklebust const struct xprt_class *t; 2351fc5f131STrond Myklebust int ret; 2361fc5f131STrond Myklebust 2371fc5f131STrond Myklebust t = xprt_class_find_by_netid(netid); 2381fc5f131STrond Myklebust if (!t) 2391fc5f131STrond Myklebust return -ENOENT; 2401fc5f131STrond Myklebust ret = t->ident; 2411fc5f131STrond Myklebust xprt_class_release(t); 2421fc5f131STrond Myklebust return ret; 2431fc5f131STrond Myklebust } 2441fc5f131STrond Myklebust EXPORT_SYMBOL_GPL(xprt_find_transport_ident); 2451fc5f131STrond Myklebust 246c544577dSTrond Myklebust static void xprt_clear_locked(struct rpc_xprt *xprt) 247c544577dSTrond Myklebust { 248c544577dSTrond Myklebust xprt->snd_task = NULL; 249c544577dSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 250c544577dSTrond Myklebust smp_mb__before_atomic(); 251c544577dSTrond Myklebust clear_bit(XPRT_LOCKED, &xprt->state); 252c544577dSTrond Myklebust smp_mb__after_atomic(); 253c544577dSTrond Myklebust } else 254c544577dSTrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 255c544577dSTrond Myklebust } 256c544577dSTrond Myklebust 257441e3e24STom Talpey /** 25812a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 25912a80469SChuck Lever * @task: task that is requesting access to the transport 260177c27bfSRandy Dunlap * @xprt: pointer to the target transport 26112a80469SChuck Lever * 26212a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 26312a80469SChuck Lever * transport connects from colliding with writes. No congestion control 26412a80469SChuck Lever * is provided. 2651da177e4SLinus Torvalds */ 26643cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 2671da177e4SLinus Torvalds { 26812a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 26912a80469SChuck Lever 27012a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 27112a80469SChuck Lever if (task == xprt->snd_task) 272bf7ca707SChuck Lever goto out_locked; 27312a80469SChuck Lever goto out_sleep; 27412a80469SChuck Lever } 275c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 276c544577dSTrond Myklebust goto out_unlock; 27712a80469SChuck Lever xprt->snd_task = task; 2784d4a76f3Sj223yang@asset.uwaterloo.ca 279bf7ca707SChuck Lever out_locked: 280bf7ca707SChuck Lever trace_xprt_reserve_xprt(xprt, task); 28112a80469SChuck Lever return 1; 28212a80469SChuck Lever 283c544577dSTrond Myklebust out_unlock: 284c544577dSTrond Myklebust xprt_clear_locked(xprt); 28512a80469SChuck Lever out_sleep: 28612a80469SChuck Lever task->tk_status = -EAGAIN; 2876b2e6856STrond Myklebust if (RPC_IS_SOFT(task)) 2886b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->sending, task, NULL, 2899e910bffSTrond Myklebust xprt_request_timeout(req)); 2906b2e6856STrond Myklebust else 29179c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 29212a80469SChuck Lever return 0; 29312a80469SChuck Lever } 29412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 29512a80469SChuck Lever 29675891f50STrond Myklebust static bool 29775891f50STrond Myklebust xprt_need_congestion_window_wait(struct rpc_xprt *xprt) 29875891f50STrond Myklebust { 29975891f50STrond Myklebust return test_bit(XPRT_CWND_WAIT, &xprt->state); 30075891f50STrond Myklebust } 30175891f50STrond Myklebust 30275891f50STrond Myklebust static void 30375891f50STrond Myklebust xprt_set_congestion_window_wait(struct rpc_xprt *xprt) 30475891f50STrond Myklebust { 30575891f50STrond Myklebust if (!list_empty(&xprt->xmit_queue)) { 30675891f50STrond Myklebust /* Peek at head of queue to see if it can make progress */ 30775891f50STrond Myklebust if (list_first_entry(&xprt->xmit_queue, struct rpc_rqst, 30875891f50STrond Myklebust rq_xmit)->rq_cong) 30975891f50STrond Myklebust return; 31075891f50STrond Myklebust } 31175891f50STrond Myklebust set_bit(XPRT_CWND_WAIT, &xprt->state); 31275891f50STrond Myklebust } 31375891f50STrond Myklebust 31475891f50STrond Myklebust static void 31575891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(struct rpc_xprt *xprt) 31675891f50STrond Myklebust { 31775891f50STrond Myklebust if (!RPCXPRT_CONGESTED(xprt)) 31875891f50STrond Myklebust clear_bit(XPRT_CWND_WAIT, &xprt->state); 31975891f50STrond Myklebust } 32075891f50STrond Myklebust 32112a80469SChuck Lever /* 32212a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 32312a80469SChuck Lever * @task: task that is requesting access to the transport 32412a80469SChuck Lever * 32512a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 32612a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 32712a80469SChuck Lever * woken up and given access to the transport. 32875891f50STrond Myklebust * Note that the lock is only granted if we know there are free slots. 32912a80469SChuck Lever */ 33043cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 33112a80469SChuck Lever { 3321da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3331da177e4SLinus Torvalds 3342226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 3351da177e4SLinus Torvalds if (task == xprt->snd_task) 336bf7ca707SChuck Lever goto out_locked; 3371da177e4SLinus Torvalds goto out_sleep; 3381da177e4SLinus Torvalds } 33943cedbf0STrond Myklebust if (req == NULL) { 34043cedbf0STrond Myklebust xprt->snd_task = task; 341bf7ca707SChuck Lever goto out_locked; 34243cedbf0STrond Myklebust } 343c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 344c544577dSTrond Myklebust goto out_unlock; 34575891f50STrond Myklebust if (!xprt_need_congestion_window_wait(xprt)) { 3461da177e4SLinus Torvalds xprt->snd_task = task; 347bf7ca707SChuck Lever goto out_locked; 3481da177e4SLinus Torvalds } 349c544577dSTrond Myklebust out_unlock: 350632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3511da177e4SLinus Torvalds out_sleep: 3521da177e4SLinus Torvalds task->tk_status = -EAGAIN; 3536b2e6856STrond Myklebust if (RPC_IS_SOFT(task)) 3546b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->sending, task, NULL, 3559e910bffSTrond Myklebust xprt_request_timeout(req)); 3566b2e6856STrond Myklebust else 35779c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 3581da177e4SLinus Torvalds return 0; 359bf7ca707SChuck Lever out_locked: 360bf7ca707SChuck Lever trace_xprt_reserve_cong(xprt, task); 361bf7ca707SChuck Lever return 1; 3621da177e4SLinus Torvalds } 36312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 3641da177e4SLinus Torvalds 36512a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 3661da177e4SLinus Torvalds { 3671da177e4SLinus Torvalds int retval; 3681da177e4SLinus Torvalds 369bd79bc57STrond Myklebust if (test_bit(XPRT_LOCKED, &xprt->state) && xprt->snd_task == task) 370bd79bc57STrond Myklebust return 1; 371b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 37243cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 373b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 3741da177e4SLinus Torvalds return retval; 3751da177e4SLinus Torvalds } 3761da177e4SLinus Torvalds 377961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 3781da177e4SLinus Torvalds { 379961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 38049e9a890SChuck Lever 38149e9a890SChuck Lever xprt->snd_task = task; 382961a828dSTrond Myklebust return true; 383961a828dSTrond Myklebust } 384961a828dSTrond Myklebust 385961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 386961a828dSTrond Myklebust { 387961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 38849e9a890SChuck Lever return; 389c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 390c544577dSTrond Myklebust goto out_unlock; 391f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 392f1dc237cSTrond Myklebust __xprt_lock_write_func, xprt)) 393961a828dSTrond Myklebust return; 394c544577dSTrond Myklebust out_unlock: 395632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 39649e9a890SChuck Lever } 39749e9a890SChuck Lever 398961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 399961a828dSTrond Myklebust { 400961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 401961a828dSTrond Myklebust return; 402c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 403c544577dSTrond Myklebust goto out_unlock; 40475891f50STrond Myklebust if (xprt_need_congestion_window_wait(xprt)) 405961a828dSTrond Myklebust goto out_unlock; 406f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 40775891f50STrond Myklebust __xprt_lock_write_func, xprt)) 408961a828dSTrond Myklebust return; 4091da177e4SLinus Torvalds out_unlock: 410632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 4111da177e4SLinus Torvalds } 4121da177e4SLinus Torvalds 41349e9a890SChuck Lever /** 41449e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 41549e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 41649e9a890SChuck Lever * @task: task that is releasing access to the transport 41749e9a890SChuck Lever * 41849e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 4191da177e4SLinus Torvalds */ 42049e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 4211da177e4SLinus Torvalds { 4221da177e4SLinus Torvalds if (xprt->snd_task == task) { 423632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 4241da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 4251da177e4SLinus Torvalds } 426bf7ca707SChuck Lever trace_xprt_release_xprt(xprt, task); 4271da177e4SLinus Torvalds } 42812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 4291da177e4SLinus Torvalds 43049e9a890SChuck Lever /** 43149e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 43249e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 43349e9a890SChuck Lever * @task: task that is releasing access to the transport 43449e9a890SChuck Lever * 43549e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 43649e9a890SChuck Lever * transport if the transport's congestion window allows it. 43749e9a890SChuck Lever */ 43849e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 43949e9a890SChuck Lever { 44049e9a890SChuck Lever if (xprt->snd_task == task) { 441632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 44249e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 44349e9a890SChuck Lever } 444bf7ca707SChuck Lever trace_xprt_release_cong(xprt, task); 44549e9a890SChuck Lever } 44612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 44749e9a890SChuck Lever 448587bc725SOlga Kornievskaia void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 4491da177e4SLinus Torvalds { 450bd79bc57STrond Myklebust if (xprt->snd_task != task) 451bd79bc57STrond Myklebust return; 452b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 45349e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 454b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 4551da177e4SLinus Torvalds } 4561da177e4SLinus Torvalds 4571da177e4SLinus Torvalds /* 4581da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 4591da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 4601da177e4SLinus Torvalds */ 4611da177e4SLinus Torvalds static int 46275891f50STrond Myklebust __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4631da177e4SLinus Torvalds { 4641da177e4SLinus Torvalds if (req->rq_cong) 4651da177e4SLinus Torvalds return 1; 466bf7ca707SChuck Lever trace_xprt_get_cong(xprt, req->rq_task); 46775891f50STrond Myklebust if (RPCXPRT_CONGESTED(xprt)) { 46875891f50STrond Myklebust xprt_set_congestion_window_wait(xprt); 4691da177e4SLinus Torvalds return 0; 47075891f50STrond Myklebust } 4711da177e4SLinus Torvalds req->rq_cong = 1; 4721da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 4731da177e4SLinus Torvalds return 1; 4741da177e4SLinus Torvalds } 4751da177e4SLinus Torvalds 4761da177e4SLinus Torvalds /* 4771da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4781da177e4SLinus Torvalds * that has been sleeping due to congestion 4791da177e4SLinus Torvalds */ 4801da177e4SLinus Torvalds static void 4811da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4821da177e4SLinus Torvalds { 4831da177e4SLinus Torvalds if (!req->rq_cong) 4841da177e4SLinus Torvalds return; 4851da177e4SLinus Torvalds req->rq_cong = 0; 4861da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 48775891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(xprt); 488bf7ca707SChuck Lever trace_xprt_put_cong(xprt, req->rq_task); 48949e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4901da177e4SLinus Torvalds } 4911da177e4SLinus Torvalds 49246c0ee8bSChuck Lever /** 49375891f50STrond Myklebust * xprt_request_get_cong - Request congestion control credits 49475891f50STrond Myklebust * @xprt: pointer to transport 49575891f50STrond Myklebust * @req: pointer to RPC request 49675891f50STrond Myklebust * 49775891f50STrond Myklebust * Useful for transports that require congestion control. 49875891f50STrond Myklebust */ 49975891f50STrond Myklebust bool 50075891f50STrond Myklebust xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 50175891f50STrond Myklebust { 50275891f50STrond Myklebust bool ret = false; 50375891f50STrond Myklebust 50475891f50STrond Myklebust if (req->rq_cong) 50575891f50STrond Myklebust return true; 506b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 50775891f50STrond Myklebust ret = __xprt_get_cong(xprt, req) != 0; 508b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 50975891f50STrond Myklebust return ret; 51075891f50STrond Myklebust } 51175891f50STrond Myklebust EXPORT_SYMBOL_GPL(xprt_request_get_cong); 51275891f50STrond Myklebust 51375891f50STrond Myklebust /** 514a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 515a58dd398SChuck Lever * @task: RPC request that recently completed 516a58dd398SChuck Lever * 517a58dd398SChuck Lever * Useful for transports that require congestion control. 518a58dd398SChuck Lever */ 519a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 520a58dd398SChuck Lever { 521a4f0835cSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 522a4f0835cSTrond Myklebust 523a4f0835cSTrond Myklebust __xprt_put_cong(req->rq_xprt, req); 524a58dd398SChuck Lever } 52512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 526a58dd398SChuck Lever 5278593e010SChuck Lever static void xprt_clear_congestion_window_wait_locked(struct rpc_xprt *xprt) 5288593e010SChuck Lever { 5298593e010SChuck Lever if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) 5308593e010SChuck Lever __xprt_lock_write_next_cong(xprt); 5318593e010SChuck Lever } 5328593e010SChuck Lever 53375891f50STrond Myklebust /* 53475891f50STrond Myklebust * Clear the congestion window wait flag and wake up the next 53575891f50STrond Myklebust * entry on xprt->sending 53675891f50STrond Myklebust */ 53775891f50STrond Myklebust static void 53875891f50STrond Myklebust xprt_clear_congestion_window_wait(struct rpc_xprt *xprt) 53975891f50STrond Myklebust { 54075891f50STrond Myklebust if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) { 541b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 54275891f50STrond Myklebust __xprt_lock_write_next_cong(xprt); 543b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 54475891f50STrond Myklebust } 54575891f50STrond Myklebust } 54675891f50STrond Myklebust 547a58dd398SChuck Lever /** 54846c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 5496a24dfb6STrond Myklebust * @xprt: pointer to xprt 55046c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 55146c0ee8bSChuck Lever * @result: result code of completed RPC request 55246c0ee8bSChuck Lever * 5534f4cf5adSChuck Lever * The transport code maintains an estimate on the maximum number of out- 5544f4cf5adSChuck Lever * standing RPC requests, using a smoothed version of the congestion 5554f4cf5adSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 5564f4cf5adSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 5574f4cf5adSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 5584f4cf5adSChuck Lever * 5594f4cf5adSChuck Lever * - a reply is received and 5604f4cf5adSChuck Lever * - a full number of requests are outstanding and 5614f4cf5adSChuck Lever * - the congestion window hasn't been updated recently. 5621da177e4SLinus Torvalds */ 5636a24dfb6STrond Myklebust void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) 5641da177e4SLinus Torvalds { 56546c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 56646c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 5671da177e4SLinus Torvalds 5681da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 5691da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 5701da177e4SLinus Torvalds * the result gets rounded properly. */ 5711da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 5721da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 5731da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 57449e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 5751da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 5761da177e4SLinus Torvalds cwnd >>= 1; 5771da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 5781da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 5791da177e4SLinus Torvalds } 5801da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 5811da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 5821da177e4SLinus Torvalds xprt->cwnd = cwnd; 58346c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 5841da177e4SLinus Torvalds } 58512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 5861da177e4SLinus Torvalds 58744fbac22SChuck Lever /** 58844fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 58944fbac22SChuck Lever * @xprt: transport with waiting tasks 59044fbac22SChuck Lever * @status: result code to plant in each task before waking it 59144fbac22SChuck Lever * 59244fbac22SChuck Lever */ 59344fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 59444fbac22SChuck Lever { 59544fbac22SChuck Lever if (status < 0) 59644fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 59744fbac22SChuck Lever else 59844fbac22SChuck Lever rpc_wake_up(&xprt->pending); 59944fbac22SChuck Lever } 60012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 60144fbac22SChuck Lever 602c7b2cae8SChuck Lever /** 603c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 604c544577dSTrond Myklebust * @xprt: transport 605a9a6b52eSTrond Myklebust * 606a9a6b52eSTrond Myklebust * Note that we only set the timer for the case of RPC_IS_SOFT(), since 607a9a6b52eSTrond Myklebust * we don't in general want to force a socket disconnection due to 608a9a6b52eSTrond Myklebust * an incomplete RPC call transmission. 609c7b2cae8SChuck Lever */ 610c544577dSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_xprt *xprt) 611c7b2cae8SChuck Lever { 612c544577dSTrond Myklebust set_bit(XPRT_WRITE_SPACE, &xprt->state); 613c7b2cae8SChuck Lever } 61412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 615c7b2cae8SChuck Lever 616c544577dSTrond Myklebust static bool 617c544577dSTrond Myklebust xprt_clear_write_space_locked(struct rpc_xprt *xprt) 618c544577dSTrond Myklebust { 619c544577dSTrond Myklebust if (test_and_clear_bit(XPRT_WRITE_SPACE, &xprt->state)) { 620c544577dSTrond Myklebust __xprt_lock_write_next(xprt); 621c544577dSTrond Myklebust dprintk("RPC: write space: waking waiting task on " 622c544577dSTrond Myklebust "xprt %p\n", xprt); 623c544577dSTrond Myklebust return true; 624c544577dSTrond Myklebust } 625c544577dSTrond Myklebust return false; 626c544577dSTrond Myklebust } 627c544577dSTrond Myklebust 628c7b2cae8SChuck Lever /** 629c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 630c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 631c7b2cae8SChuck Lever * 632c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 633c7b2cae8SChuck Lever */ 634c544577dSTrond Myklebust bool xprt_write_space(struct rpc_xprt *xprt) 635c7b2cae8SChuck Lever { 636c544577dSTrond Myklebust bool ret; 637c544577dSTrond Myklebust 638c544577dSTrond Myklebust if (!test_bit(XPRT_WRITE_SPACE, &xprt->state)) 639c544577dSTrond Myklebust return false; 640b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 641c544577dSTrond Myklebust ret = xprt_clear_write_space_locked(xprt); 642b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 643c544577dSTrond Myklebust return ret; 644c7b2cae8SChuck Lever } 64512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 646c7b2cae8SChuck Lever 647da953063STrond Myklebust static unsigned long xprt_abs_ktime_to_jiffies(ktime_t abstime) 648da953063STrond Myklebust { 649da953063STrond Myklebust s64 delta = ktime_to_ns(ktime_get() - abstime); 650da953063STrond Myklebust return likely(delta >= 0) ? 651da953063STrond Myklebust jiffies - nsecs_to_jiffies(delta) : 652da953063STrond Myklebust jiffies + nsecs_to_jiffies(-delta); 653da953063STrond Myklebust } 654da953063STrond Myklebust 655da953063STrond Myklebust static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req) 6561da177e4SLinus Torvalds { 657ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 658da953063STrond Myklebust unsigned long majortimeo = req->rq_timeout; 6591da177e4SLinus Torvalds 6601da177e4SLinus Torvalds if (to->to_exponential) 661da953063STrond Myklebust majortimeo <<= to->to_retries; 6621da177e4SLinus Torvalds else 663da953063STrond Myklebust majortimeo += to->to_increment * to->to_retries; 664da953063STrond Myklebust if (majortimeo > to->to_maxval || majortimeo == 0) 665da953063STrond Myklebust majortimeo = to->to_maxval; 666da953063STrond Myklebust return majortimeo; 667da953063STrond Myklebust } 668da953063STrond Myklebust 669da953063STrond Myklebust static void xprt_reset_majortimeo(struct rpc_rqst *req) 670da953063STrond Myklebust { 671da953063STrond Myklebust req->rq_majortimeo += xprt_calc_majortimeo(req); 672da953063STrond Myklebust } 673da953063STrond Myklebust 6747de62bc0SOlga Kornievskaia static void xprt_reset_minortimeo(struct rpc_rqst *req) 6757de62bc0SOlga Kornievskaia { 6767de62bc0SOlga Kornievskaia req->rq_minortimeo += req->rq_timeout; 6777de62bc0SOlga Kornievskaia } 6787de62bc0SOlga Kornievskaia 679da953063STrond Myklebust static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req) 680da953063STrond Myklebust { 681da953063STrond Myklebust unsigned long time_init; 682da953063STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 683da953063STrond Myklebust 684da953063STrond Myklebust if (likely(xprt && xprt_connected(xprt))) 685da953063STrond Myklebust time_init = jiffies; 686da953063STrond Myklebust else 687da953063STrond Myklebust time_init = xprt_abs_ktime_to_jiffies(task->tk_start); 688da953063STrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 689da953063STrond Myklebust req->rq_majortimeo = time_init + xprt_calc_majortimeo(req); 6907de62bc0SOlga Kornievskaia req->rq_minortimeo = time_init + req->rq_timeout; 6911da177e4SLinus Torvalds } 6921da177e4SLinus Torvalds 6939903cd1cSChuck Lever /** 6949903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 6959903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 6969903cd1cSChuck Lever * 6971da177e4SLinus Torvalds */ 6981da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 6991da177e4SLinus Torvalds { 7001da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 701ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 7021da177e4SLinus Torvalds int status = 0; 7031da177e4SLinus Torvalds 70409252177SChris Dion if (time_before(jiffies, req->rq_majortimeo)) { 7057de62bc0SOlga Kornievskaia if (time_before(jiffies, req->rq_minortimeo)) 7067de62bc0SOlga Kornievskaia return status; 7071da177e4SLinus Torvalds if (to->to_exponential) 7081da177e4SLinus Torvalds req->rq_timeout <<= 1; 7091da177e4SLinus Torvalds else 7101da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 7111da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 7121da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 7131da177e4SLinus Torvalds req->rq_retries++; 7141da177e4SLinus Torvalds } else { 7151da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 7161da177e4SLinus Torvalds req->rq_retries = 0; 7171da177e4SLinus Torvalds xprt_reset_majortimeo(req); 7181da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 719b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 7201da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 721b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 7221da177e4SLinus Torvalds status = -ETIMEDOUT; 7231da177e4SLinus Torvalds } 7247de62bc0SOlga Kornievskaia xprt_reset_minortimeo(req); 7251da177e4SLinus Torvalds 7261da177e4SLinus Torvalds if (req->rq_timeout == 0) { 7271da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 7281da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 7291da177e4SLinus Torvalds } 7301da177e4SLinus Torvalds return status; 7311da177e4SLinus Torvalds } 7321da177e4SLinus Torvalds 73365f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 7341da177e4SLinus Torvalds { 73565f27f38SDavid Howells struct rpc_xprt *xprt = 73665f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 737a1231fdaSTrond Myklebust unsigned int pflags = memalloc_nofs_save(); 7381da177e4SLinus Torvalds 739911813d7SChuck Lever trace_xprt_disconnect_auto(xprt); 74066af1e55STrond Myklebust clear_bit(XPRT_CLOSE_WAIT, &xprt->state); 7414876cc77STrond Myklebust xprt->ops->close(xprt); 7421da177e4SLinus Torvalds xprt_release_write(xprt, NULL); 74379234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 744a1231fdaSTrond Myklebust memalloc_nofs_restore(pflags); 7451da177e4SLinus Torvalds } 7461da177e4SLinus Torvalds 7479903cd1cSChuck Lever /** 74862da3b24STrond Myklebust * xprt_disconnect_done - mark a transport as disconnected 7499903cd1cSChuck Lever * @xprt: transport to flag for disconnect 7509903cd1cSChuck Lever * 7511da177e4SLinus Torvalds */ 75262da3b24STrond Myklebust void xprt_disconnect_done(struct rpc_xprt *xprt) 7531da177e4SLinus Torvalds { 754911813d7SChuck Lever trace_xprt_disconnect_done(xprt); 755b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 7561da177e4SLinus Torvalds xprt_clear_connected(xprt); 757c544577dSTrond Myklebust xprt_clear_write_space_locked(xprt); 7588593e010SChuck Lever xprt_clear_congestion_window_wait_locked(xprt); 75927adc785STrond Myklebust xprt_wake_pending_tasks(xprt, -ENOTCONN); 760b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 7611da177e4SLinus Torvalds } 76262da3b24STrond Myklebust EXPORT_SYMBOL_GPL(xprt_disconnect_done); 7631da177e4SLinus Torvalds 76466af1e55STrond Myklebust /** 76566af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 76666af1e55STrond Myklebust * @xprt: transport to disconnect 76766af1e55STrond Myklebust * 76866af1e55STrond Myklebust */ 76966af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 77066af1e55STrond Myklebust { 771911813d7SChuck Lever trace_xprt_disconnect_force(xprt); 772911813d7SChuck Lever 77366af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 774b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 77566af1e55STrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 77666af1e55STrond Myklebust /* Try to schedule an autoclose RPC call */ 77766af1e55STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 77840a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 7790445f92cSTrond Myklebust else if (xprt->snd_task) 7800445f92cSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 7810445f92cSTrond Myklebust xprt->snd_task, -ENOTCONN); 782b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 78366af1e55STrond Myklebust } 784e2a4f4fbSChuck Lever EXPORT_SYMBOL_GPL(xprt_force_disconnect); 78566af1e55STrond Myklebust 7867f3a1d1eSTrond Myklebust static unsigned int 7877f3a1d1eSTrond Myklebust xprt_connect_cookie(struct rpc_xprt *xprt) 7887f3a1d1eSTrond Myklebust { 7897f3a1d1eSTrond Myklebust return READ_ONCE(xprt->connect_cookie); 7907f3a1d1eSTrond Myklebust } 7917f3a1d1eSTrond Myklebust 7927f3a1d1eSTrond Myklebust static bool 7937f3a1d1eSTrond Myklebust xprt_request_retransmit_after_disconnect(struct rpc_task *task) 7947f3a1d1eSTrond Myklebust { 7957f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 7967f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 7977f3a1d1eSTrond Myklebust 7987f3a1d1eSTrond Myklebust return req->rq_connect_cookie != xprt_connect_cookie(xprt) || 7997f3a1d1eSTrond Myklebust !xprt_connected(xprt); 8007f3a1d1eSTrond Myklebust } 8017f3a1d1eSTrond Myklebust 8027c1d71cfSTrond Myklebust /** 8037c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 8047c1d71cfSTrond Myklebust * @xprt: transport to disconnect 8057c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 8067c1d71cfSTrond Myklebust * 8077c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 8087c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 8097c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 8107c1d71cfSTrond Myklebust * a batch of RPC requests. 8117c1d71cfSTrond Myklebust * 8127c1d71cfSTrond Myklebust */ 8137c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 8147c1d71cfSTrond Myklebust { 8157c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 816b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 8177c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 8187c1d71cfSTrond Myklebust goto out; 8192c2ee6d2SNeilBrown if (test_bit(XPRT_CLOSING, &xprt->state)) 8207c1d71cfSTrond Myklebust goto out; 8217c1d71cfSTrond Myklebust set_bit(XPRT_CLOSE_WAIT, &xprt->state); 8227c1d71cfSTrond Myklebust /* Try to schedule an autoclose RPC call */ 8237c1d71cfSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 82440a5f1b1STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 8252a491991STrond Myklebust xprt_wake_pending_tasks(xprt, -EAGAIN); 8267c1d71cfSTrond Myklebust out: 827b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 8287c1d71cfSTrond Myklebust } 8297c1d71cfSTrond Myklebust 830ad3331acSTrond Myklebust static bool 831ad3331acSTrond Myklebust xprt_has_timer(const struct rpc_xprt *xprt) 832ad3331acSTrond Myklebust { 833ad3331acSTrond Myklebust return xprt->idle_timeout != 0; 834ad3331acSTrond Myklebust } 835ad3331acSTrond Myklebust 836ad3331acSTrond Myklebust static void 837ad3331acSTrond Myklebust xprt_schedule_autodisconnect(struct rpc_xprt *xprt) 838ad3331acSTrond Myklebust __must_hold(&xprt->transport_lock) 839ad3331acSTrond Myklebust { 84080d3c45fSDave Wysochanski xprt->last_used = jiffies; 84195f7691dSTrond Myklebust if (RB_EMPTY_ROOT(&xprt->recv_queue) && xprt_has_timer(xprt)) 842ad3331acSTrond Myklebust mod_timer(&xprt->timer, xprt->last_used + xprt->idle_timeout); 843ad3331acSTrond Myklebust } 844ad3331acSTrond Myklebust 8451da177e4SLinus Torvalds static void 846ff861c4dSKees Cook xprt_init_autodisconnect(struct timer_list *t) 8471da177e4SLinus Torvalds { 848ff861c4dSKees Cook struct rpc_xprt *xprt = from_timer(xprt, t, timer); 8491da177e4SLinus Torvalds 85095f7691dSTrond Myklebust if (!RB_EMPTY_ROOT(&xprt->recv_queue)) 851b5e92419STrond Myklebust return; 852ad3331acSTrond Myklebust /* Reset xprt->last_used to avoid connect/autodisconnect cycling */ 853ad3331acSTrond Myklebust xprt->last_used = jiffies; 8542226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 8551da177e4SLinus Torvalds return; 856b5e92419STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 8571da177e4SLinus Torvalds } 8581da177e4SLinus Torvalds 859*a4ae3081SChuck Lever #if IS_ENABLED(CONFIG_FAIL_SUNRPC) 860*a4ae3081SChuck Lever static void xprt_inject_disconnect(struct rpc_xprt *xprt) 861*a4ae3081SChuck Lever { 862*a4ae3081SChuck Lever if (!fail_sunrpc.ignore_client_disconnect && 863*a4ae3081SChuck Lever should_fail(&fail_sunrpc.attr, 1)) 864*a4ae3081SChuck Lever xprt->ops->inject_disconnect(xprt); 865*a4ae3081SChuck Lever } 866*a4ae3081SChuck Lever #else 867*a4ae3081SChuck Lever static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 868*a4ae3081SChuck Lever { 869*a4ae3081SChuck Lever } 870*a4ae3081SChuck Lever #endif 871*a4ae3081SChuck Lever 872718ba5b8STrond Myklebust bool xprt_lock_connect(struct rpc_xprt *xprt, 873718ba5b8STrond Myklebust struct rpc_task *task, 874718ba5b8STrond Myklebust void *cookie) 875718ba5b8STrond Myklebust { 876718ba5b8STrond Myklebust bool ret = false; 877718ba5b8STrond Myklebust 878b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 879718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 880718ba5b8STrond Myklebust goto out; 881718ba5b8STrond Myklebust if (xprt->snd_task != task) 882718ba5b8STrond Myklebust goto out; 883718ba5b8STrond Myklebust xprt->snd_task = cookie; 884718ba5b8STrond Myklebust ret = true; 885718ba5b8STrond Myklebust out: 886b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 887718ba5b8STrond Myklebust return ret; 888718ba5b8STrond Myklebust } 889718ba5b8STrond Myklebust 890718ba5b8STrond Myklebust void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) 891718ba5b8STrond Myklebust { 892b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 893718ba5b8STrond Myklebust if (xprt->snd_task != cookie) 894718ba5b8STrond Myklebust goto out; 895718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 896718ba5b8STrond Myklebust goto out; 897718ba5b8STrond Myklebust xprt->snd_task =NULL; 898718ba5b8STrond Myklebust xprt->ops->release_xprt(xprt, NULL); 899ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 900718ba5b8STrond Myklebust out: 901b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 90279234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 903718ba5b8STrond Myklebust } 904718ba5b8STrond Myklebust 9059903cd1cSChuck Lever /** 9069903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 9079903cd1cSChuck Lever * @task: RPC task that is requesting the connect 9081da177e4SLinus Torvalds * 9091da177e4SLinus Torvalds */ 9101da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 9111da177e4SLinus Torvalds { 912ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 9131da177e4SLinus Torvalds 914db0a86c4SChuck Lever trace_xprt_connect(xprt); 9151da177e4SLinus Torvalds 916ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 91701d37c42STrond Myklebust task->tk_status = -EAGAIN; 9181da177e4SLinus Torvalds return; 9191da177e4SLinus Torvalds } 9201da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 9211da177e4SLinus Torvalds return; 922feb8ca37STrond Myklebust 923911813d7SChuck Lever if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 924911813d7SChuck Lever trace_xprt_disconnect_cleanup(xprt); 925feb8ca37STrond Myklebust xprt->ops->close(xprt); 926911813d7SChuck Lever } 927feb8ca37STrond Myklebust 928718ba5b8STrond Myklebust if (!xprt_connected(xprt)) { 9292c2ee6d2SNeilBrown task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie; 9306b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->pending, task, NULL, 9319e910bffSTrond Myklebust xprt_request_timeout(task->tk_rqstp)); 9320b9e7943STrond Myklebust 9330b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 9340b9e7943STrond Myklebust return; 9350b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 9360b9e7943STrond Myklebust return; 9370a9a4304STrond Myklebust /* Race breaker */ 9380a9a4304STrond Myklebust if (!xprt_connected(xprt)) { 939262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 9401b092092STrond Myklebust xprt->ops->connect(xprt, task); 9410a9a4304STrond Myklebust } else { 9420a9a4304STrond Myklebust xprt_clear_connecting(xprt); 9430a9a4304STrond Myklebust task->tk_status = 0; 9440a9a4304STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 9450a9a4304STrond Myklebust } 9461da177e4SLinus Torvalds } 947718ba5b8STrond Myklebust xprt_release_write(xprt, task); 9481da177e4SLinus Torvalds } 9491da177e4SLinus Torvalds 950675dd90aSChuck Lever /** 951675dd90aSChuck Lever * xprt_reconnect_delay - compute the wait before scheduling a connect 952675dd90aSChuck Lever * @xprt: transport instance 953675dd90aSChuck Lever * 954675dd90aSChuck Lever */ 955675dd90aSChuck Lever unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt) 956675dd90aSChuck Lever { 957675dd90aSChuck Lever unsigned long start, now = jiffies; 958675dd90aSChuck Lever 959675dd90aSChuck Lever start = xprt->stat.connect_start + xprt->reestablish_timeout; 960675dd90aSChuck Lever if (time_after(start, now)) 961675dd90aSChuck Lever return start - now; 962675dd90aSChuck Lever return 0; 963675dd90aSChuck Lever } 964675dd90aSChuck Lever EXPORT_SYMBOL_GPL(xprt_reconnect_delay); 965675dd90aSChuck Lever 966675dd90aSChuck Lever /** 967675dd90aSChuck Lever * xprt_reconnect_backoff - compute the new re-establish timeout 968675dd90aSChuck Lever * @xprt: transport instance 969675dd90aSChuck Lever * @init_to: initial reestablish timeout 970675dd90aSChuck Lever * 971675dd90aSChuck Lever */ 972675dd90aSChuck Lever void xprt_reconnect_backoff(struct rpc_xprt *xprt, unsigned long init_to) 973675dd90aSChuck Lever { 974675dd90aSChuck Lever xprt->reestablish_timeout <<= 1; 975675dd90aSChuck Lever if (xprt->reestablish_timeout > xprt->max_reconnect_timeout) 976675dd90aSChuck Lever xprt->reestablish_timeout = xprt->max_reconnect_timeout; 977675dd90aSChuck Lever if (xprt->reestablish_timeout < init_to) 978675dd90aSChuck Lever xprt->reestablish_timeout = init_to; 979675dd90aSChuck Lever } 980675dd90aSChuck Lever EXPORT_SYMBOL_GPL(xprt_reconnect_backoff); 981675dd90aSChuck Lever 98295f7691dSTrond Myklebust enum xprt_xid_rb_cmp { 98395f7691dSTrond Myklebust XID_RB_EQUAL, 98495f7691dSTrond Myklebust XID_RB_LEFT, 98595f7691dSTrond Myklebust XID_RB_RIGHT, 98695f7691dSTrond Myklebust }; 98795f7691dSTrond Myklebust static enum xprt_xid_rb_cmp 98895f7691dSTrond Myklebust xprt_xid_cmp(__be32 xid1, __be32 xid2) 98995f7691dSTrond Myklebust { 99095f7691dSTrond Myklebust if (xid1 == xid2) 99195f7691dSTrond Myklebust return XID_RB_EQUAL; 99295f7691dSTrond Myklebust if ((__force u32)xid1 < (__force u32)xid2) 99395f7691dSTrond Myklebust return XID_RB_LEFT; 99495f7691dSTrond Myklebust return XID_RB_RIGHT; 99595f7691dSTrond Myklebust } 99695f7691dSTrond Myklebust 99795f7691dSTrond Myklebust static struct rpc_rqst * 99895f7691dSTrond Myklebust xprt_request_rb_find(struct rpc_xprt *xprt, __be32 xid) 99995f7691dSTrond Myklebust { 100095f7691dSTrond Myklebust struct rb_node *n = xprt->recv_queue.rb_node; 100195f7691dSTrond Myklebust struct rpc_rqst *req; 100295f7691dSTrond Myklebust 100395f7691dSTrond Myklebust while (n != NULL) { 100495f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 100595f7691dSTrond Myklebust switch (xprt_xid_cmp(xid, req->rq_xid)) { 100695f7691dSTrond Myklebust case XID_RB_LEFT: 100795f7691dSTrond Myklebust n = n->rb_left; 100895f7691dSTrond Myklebust break; 100995f7691dSTrond Myklebust case XID_RB_RIGHT: 101095f7691dSTrond Myklebust n = n->rb_right; 101195f7691dSTrond Myklebust break; 101295f7691dSTrond Myklebust case XID_RB_EQUAL: 101395f7691dSTrond Myklebust return req; 101495f7691dSTrond Myklebust } 101595f7691dSTrond Myklebust } 101695f7691dSTrond Myklebust return NULL; 101795f7691dSTrond Myklebust } 101895f7691dSTrond Myklebust 101995f7691dSTrond Myklebust static void 102095f7691dSTrond Myklebust xprt_request_rb_insert(struct rpc_xprt *xprt, struct rpc_rqst *new) 102195f7691dSTrond Myklebust { 102295f7691dSTrond Myklebust struct rb_node **p = &xprt->recv_queue.rb_node; 102395f7691dSTrond Myklebust struct rb_node *n = NULL; 102495f7691dSTrond Myklebust struct rpc_rqst *req; 102595f7691dSTrond Myklebust 102695f7691dSTrond Myklebust while (*p != NULL) { 102795f7691dSTrond Myklebust n = *p; 102895f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 102995f7691dSTrond Myklebust switch(xprt_xid_cmp(new->rq_xid, req->rq_xid)) { 103095f7691dSTrond Myklebust case XID_RB_LEFT: 103195f7691dSTrond Myklebust p = &n->rb_left; 103295f7691dSTrond Myklebust break; 103395f7691dSTrond Myklebust case XID_RB_RIGHT: 103495f7691dSTrond Myklebust p = &n->rb_right; 103595f7691dSTrond Myklebust break; 103695f7691dSTrond Myklebust case XID_RB_EQUAL: 103795f7691dSTrond Myklebust WARN_ON_ONCE(new != req); 103895f7691dSTrond Myklebust return; 103995f7691dSTrond Myklebust } 104095f7691dSTrond Myklebust } 104195f7691dSTrond Myklebust rb_link_node(&new->rq_recv, n, p); 104295f7691dSTrond Myklebust rb_insert_color(&new->rq_recv, &xprt->recv_queue); 104395f7691dSTrond Myklebust } 104495f7691dSTrond Myklebust 104595f7691dSTrond Myklebust static void 104695f7691dSTrond Myklebust xprt_request_rb_remove(struct rpc_xprt *xprt, struct rpc_rqst *req) 104795f7691dSTrond Myklebust { 104895f7691dSTrond Myklebust rb_erase(&req->rq_recv, &xprt->recv_queue); 104995f7691dSTrond Myklebust } 105095f7691dSTrond Myklebust 10519903cd1cSChuck Lever /** 10529903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 10539903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 10549903cd1cSChuck Lever * @xid: RPC XID of incoming reply 10559903cd1cSChuck Lever * 105675c84151STrond Myklebust * Caller holds xprt->queue_lock. 10571da177e4SLinus Torvalds */ 1058d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 10591da177e4SLinus Torvalds { 10608f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 10611da177e4SLinus Torvalds 106295f7691dSTrond Myklebust entry = xprt_request_rb_find(xprt, xid); 106395f7691dSTrond Myklebust if (entry != NULL) { 10643705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, 0); 10650b87a46bSChuck Lever entry->rq_rtt = ktime_sub(ktime_get(), entry->rq_xtime); 1066262ca07dSChuck Lever return entry; 10673705ad64SJeff Layton } 106846121cf7SChuck Lever 106946121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 107046121cf7SChuck Lever ntohl(xid)); 10713705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, -ENOENT); 1072262ca07dSChuck Lever xprt->stat.bad_xids++; 1073262ca07dSChuck Lever return NULL; 10741da177e4SLinus Torvalds } 107512444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 10761da177e4SLinus Torvalds 1077cf9946cdSTrond Myklebust static bool 1078cf9946cdSTrond Myklebust xprt_is_pinned_rqst(struct rpc_rqst *req) 1079cf9946cdSTrond Myklebust { 1080cf9946cdSTrond Myklebust return atomic_read(&req->rq_pin) != 0; 1081cf9946cdSTrond Myklebust } 1082cf9946cdSTrond Myklebust 1083729749bbSTrond Myklebust /** 1084729749bbSTrond Myklebust * xprt_pin_rqst - Pin a request on the transport receive list 1085729749bbSTrond Myklebust * @req: Request to pin 1086729749bbSTrond Myklebust * 1087729749bbSTrond Myklebust * Caller must ensure this is atomic with the call to xprt_lookup_rqst() 10881f7d1c73SChuck Lever * so should be holding xprt->queue_lock. 1089729749bbSTrond Myklebust */ 1090729749bbSTrond Myklebust void xprt_pin_rqst(struct rpc_rqst *req) 1091729749bbSTrond Myklebust { 1092cf9946cdSTrond Myklebust atomic_inc(&req->rq_pin); 1093729749bbSTrond Myklebust } 10949590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_pin_rqst); 1095729749bbSTrond Myklebust 1096729749bbSTrond Myklebust /** 1097729749bbSTrond Myklebust * xprt_unpin_rqst - Unpin a request on the transport receive list 1098729749bbSTrond Myklebust * @req: Request to pin 1099729749bbSTrond Myklebust * 11001f7d1c73SChuck Lever * Caller should be holding xprt->queue_lock. 1101729749bbSTrond Myklebust */ 1102729749bbSTrond Myklebust void xprt_unpin_rqst(struct rpc_rqst *req) 1103729749bbSTrond Myklebust { 1104cf9946cdSTrond Myklebust if (!test_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate)) { 1105cf9946cdSTrond Myklebust atomic_dec(&req->rq_pin); 1106cf9946cdSTrond Myklebust return; 1107cf9946cdSTrond Myklebust } 1108cf9946cdSTrond Myklebust if (atomic_dec_and_test(&req->rq_pin)) 1109cf9946cdSTrond Myklebust wake_up_var(&req->rq_pin); 1110729749bbSTrond Myklebust } 11119590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_unpin_rqst); 1112729749bbSTrond Myklebust 1113729749bbSTrond Myklebust static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) 1114729749bbSTrond Myklebust { 1115cf9946cdSTrond Myklebust wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); 1116729749bbSTrond Myklebust } 1117729749bbSTrond Myklebust 1118edc81dcdSTrond Myklebust static bool 1119edc81dcdSTrond Myklebust xprt_request_data_received(struct rpc_task *task) 1120edc81dcdSTrond Myklebust { 1121edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 1122edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; 1123edc81dcdSTrond Myklebust } 1124edc81dcdSTrond Myklebust 1125edc81dcdSTrond Myklebust static bool 1126edc81dcdSTrond Myklebust xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst *req) 1127edc81dcdSTrond Myklebust { 1128edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 1129edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) == 0; 1130edc81dcdSTrond Myklebust } 1131edc81dcdSTrond Myklebust 1132edc81dcdSTrond Myklebust /** 1133edc81dcdSTrond Myklebust * xprt_request_enqueue_receive - Add an request to the receive queue 1134edc81dcdSTrond Myklebust * @task: RPC task 1135edc81dcdSTrond Myklebust * 1136edc81dcdSTrond Myklebust */ 1137edc81dcdSTrond Myklebust void 1138edc81dcdSTrond Myklebust xprt_request_enqueue_receive(struct rpc_task *task) 1139edc81dcdSTrond Myklebust { 1140edc81dcdSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1141edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1142edc81dcdSTrond Myklebust 1143edc81dcdSTrond Myklebust if (!xprt_request_need_enqueue_receive(task, req)) 1144edc81dcdSTrond Myklebust return; 114575369089STrond Myklebust 114675369089STrond Myklebust xprt_request_prepare(task->tk_rqstp); 1147edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1148edc81dcdSTrond Myklebust 1149edc81dcdSTrond Myklebust /* Update the softirq receive buffer */ 1150edc81dcdSTrond Myklebust memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 1151edc81dcdSTrond Myklebust sizeof(req->rq_private_buf)); 1152edc81dcdSTrond Myklebust 1153edc81dcdSTrond Myklebust /* Add request to the receive list */ 115495f7691dSTrond Myklebust xprt_request_rb_insert(xprt, req); 1155edc81dcdSTrond Myklebust set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); 1156edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1157edc81dcdSTrond Myklebust 1158edc81dcdSTrond Myklebust /* Turn off autodisconnect */ 1159edc81dcdSTrond Myklebust del_singleshot_timer_sync(&xprt->timer); 1160edc81dcdSTrond Myklebust } 1161edc81dcdSTrond Myklebust 1162edc81dcdSTrond Myklebust /** 1163edc81dcdSTrond Myklebust * xprt_request_dequeue_receive_locked - Remove a request from the receive queue 1164edc81dcdSTrond Myklebust * @task: RPC task 1165edc81dcdSTrond Myklebust * 1166edc81dcdSTrond Myklebust * Caller must hold xprt->queue_lock. 1167edc81dcdSTrond Myklebust */ 1168edc81dcdSTrond Myklebust static void 1169edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(struct rpc_task *task) 1170edc81dcdSTrond Myklebust { 117195f7691dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 117295f7691dSTrond Myklebust 1173edc81dcdSTrond Myklebust if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 117495f7691dSTrond Myklebust xprt_request_rb_remove(req->rq_xprt, req); 1175edc81dcdSTrond Myklebust } 1176edc81dcdSTrond Myklebust 1177ecd465eeSChuck Lever /** 1178ecd465eeSChuck Lever * xprt_update_rtt - Update RPC RTT statistics 1179ecd465eeSChuck Lever * @task: RPC request that recently completed 1180ecd465eeSChuck Lever * 118175c84151STrond Myklebust * Caller holds xprt->queue_lock. 1182ecd465eeSChuck Lever */ 1183ecd465eeSChuck Lever void xprt_update_rtt(struct rpc_task *task) 11841da177e4SLinus Torvalds { 11851570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 11861570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 118795c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 1188d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 11891570c1e4SChuck Lever 11901da177e4SLinus Torvalds if (timer) { 11911da177e4SLinus Torvalds if (req->rq_ntrans == 1) 1192ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 11931570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 11941da177e4SLinus Torvalds } 11951da177e4SLinus Torvalds } 1196ecd465eeSChuck Lever EXPORT_SYMBOL_GPL(xprt_update_rtt); 11971da177e4SLinus Torvalds 11981570c1e4SChuck Lever /** 11991570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 12001570c1e4SChuck Lever * @task: RPC request that recently completed 12011570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 12021570c1e4SChuck Lever * 120375c84151STrond Myklebust * Caller holds xprt->queue_lock. 12041570c1e4SChuck Lever */ 12051570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 12061570c1e4SChuck Lever { 12071570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 1208fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12091da177e4SLinus Torvalds 1210fda13939STrond Myklebust xprt->stat.recvs++; 1211ef759a2eSChuck Lever 12121e799b67STrond Myklebust req->rq_private_buf.len = copied; 1213dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 1214dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 121543ac3f29STrond Myklebust smp_wmb(); 1216dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 1217edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 1218fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 12191da177e4SLinus Torvalds } 122012444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 12211da177e4SLinus Torvalds 122246c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 12231da177e4SLinus Torvalds { 12241da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 12251da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 12261da177e4SLinus Torvalds 12275d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 12285d00837bSTrond Myklebust return; 122946c0ee8bSChuck Lever 123082476d9fSChuck Lever trace_xprt_timer(xprt, req->rq_xid, task->tk_status); 1231dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 123246c0ee8bSChuck Lever if (xprt->ops->timer) 12336a24dfb6STrond Myklebust xprt->ops->timer(xprt, task); 12345d00837bSTrond Myklebust } else 12355d00837bSTrond Myklebust task->tk_status = 0; 12361da177e4SLinus Torvalds } 12371da177e4SLinus Torvalds 12389903cd1cSChuck Lever /** 12398ba6a92dSTrond Myklebust * xprt_wait_for_reply_request_def - wait for reply 12408ba6a92dSTrond Myklebust * @task: pointer to rpc_task 12418ba6a92dSTrond Myklebust * 12428ba6a92dSTrond Myklebust * Set a request's retransmit timeout based on the transport's 12438ba6a92dSTrond Myklebust * default timeout parameters. Used by transports that don't adjust 12448ba6a92dSTrond Myklebust * the retransmit timeout based on round-trip time estimation, 12458ba6a92dSTrond Myklebust * and put the task to sleep on the pending queue. 12468ba6a92dSTrond Myklebust */ 12478ba6a92dSTrond Myklebust void xprt_wait_for_reply_request_def(struct rpc_task *task) 12488ba6a92dSTrond Myklebust { 12498ba6a92dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12508ba6a92dSTrond Myklebust 12516b2e6856STrond Myklebust rpc_sleep_on_timeout(&req->rq_xprt->pending, task, xprt_timer, 12529e910bffSTrond Myklebust xprt_request_timeout(req)); 12538ba6a92dSTrond Myklebust } 12548ba6a92dSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_wait_for_reply_request_def); 12558ba6a92dSTrond Myklebust 12568ba6a92dSTrond Myklebust /** 12578ba6a92dSTrond Myklebust * xprt_wait_for_reply_request_rtt - wait for reply using RTT estimator 12588ba6a92dSTrond Myklebust * @task: pointer to rpc_task 12598ba6a92dSTrond Myklebust * 12608ba6a92dSTrond Myklebust * Set a request's retransmit timeout using the RTT estimator, 12618ba6a92dSTrond Myklebust * and put the task to sleep on the pending queue. 12628ba6a92dSTrond Myklebust */ 12638ba6a92dSTrond Myklebust void xprt_wait_for_reply_request_rtt(struct rpc_task *task) 12648ba6a92dSTrond Myklebust { 12658ba6a92dSTrond Myklebust int timer = task->tk_msg.rpc_proc->p_timer; 12668ba6a92dSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 12678ba6a92dSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 12688ba6a92dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12698ba6a92dSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 12706b2e6856STrond Myklebust unsigned long timeout; 12718ba6a92dSTrond Myklebust 12726b2e6856STrond Myklebust timeout = rpc_calc_rto(rtt, timer); 12736b2e6856STrond Myklebust timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 12746b2e6856STrond Myklebust if (timeout > max_timeout || timeout == 0) 12756b2e6856STrond Myklebust timeout = max_timeout; 12766b2e6856STrond Myklebust rpc_sleep_on_timeout(&req->rq_xprt->pending, task, xprt_timer, 12776b2e6856STrond Myklebust jiffies + timeout); 12788ba6a92dSTrond Myklebust } 12798ba6a92dSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_wait_for_reply_request_rtt); 12808ba6a92dSTrond Myklebust 12818ba6a92dSTrond Myklebust /** 12827f3a1d1eSTrond Myklebust * xprt_request_wait_receive - wait for the reply to an RPC request 12837f3a1d1eSTrond Myklebust * @task: RPC task about to send a request 12847f3a1d1eSTrond Myklebust * 12857f3a1d1eSTrond Myklebust */ 12867f3a1d1eSTrond Myklebust void xprt_request_wait_receive(struct rpc_task *task) 12877f3a1d1eSTrond Myklebust { 12887f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12897f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12907f3a1d1eSTrond Myklebust 12917f3a1d1eSTrond Myklebust if (!test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 12927f3a1d1eSTrond Myklebust return; 12937f3a1d1eSTrond Myklebust /* 12947f3a1d1eSTrond Myklebust * Sleep on the pending queue if we're expecting a reply. 12957f3a1d1eSTrond Myklebust * The spinlock ensures atomicity between the test of 12967f3a1d1eSTrond Myklebust * req->rq_reply_bytes_recvd, and the call to rpc_sleep_on(). 12977f3a1d1eSTrond Myklebust */ 12987f3a1d1eSTrond Myklebust spin_lock(&xprt->queue_lock); 12997f3a1d1eSTrond Myklebust if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) { 13008ba6a92dSTrond Myklebust xprt->ops->wait_for_reply_request(task); 13017f3a1d1eSTrond Myklebust /* 13027f3a1d1eSTrond Myklebust * Send an extra queue wakeup call if the 13037f3a1d1eSTrond Myklebust * connection was dropped in case the call to 13047f3a1d1eSTrond Myklebust * rpc_sleep_on() raced. 13057f3a1d1eSTrond Myklebust */ 13067f3a1d1eSTrond Myklebust if (xprt_request_retransmit_after_disconnect(task)) 13077f3a1d1eSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 13087f3a1d1eSTrond Myklebust task, -ENOTCONN); 13097f3a1d1eSTrond Myklebust } 13107f3a1d1eSTrond Myklebust spin_unlock(&xprt->queue_lock); 13117f3a1d1eSTrond Myklebust } 13127f3a1d1eSTrond Myklebust 1313944b0429STrond Myklebust static bool 1314944b0429STrond Myklebust xprt_request_need_enqueue_transmit(struct rpc_task *task, struct rpc_rqst *req) 1315944b0429STrond Myklebust { 1316762e4e67STrond Myklebust return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1317944b0429STrond Myklebust } 1318944b0429STrond Myklebust 1319944b0429STrond Myklebust /** 1320944b0429STrond Myklebust * xprt_request_enqueue_transmit - queue a task for transmission 1321944b0429STrond Myklebust * @task: pointer to rpc_task 1322944b0429STrond Myklebust * 1323944b0429STrond Myklebust * Add a task to the transmission queue. 1324944b0429STrond Myklebust */ 1325944b0429STrond Myklebust void 1326944b0429STrond Myklebust xprt_request_enqueue_transmit(struct rpc_task *task) 1327944b0429STrond Myklebust { 1328918f3c1fSTrond Myklebust struct rpc_rqst *pos, *req = task->tk_rqstp; 1329944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1330944b0429STrond Myklebust 1331944b0429STrond Myklebust if (xprt_request_need_enqueue_transmit(task, req)) { 1332e66721f0STrond Myklebust req->rq_bytes_sent = 0; 1333944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 133475891f50STrond Myklebust /* 133575891f50STrond Myklebust * Requests that carry congestion control credits are added 133675891f50STrond Myklebust * to the head of the list to avoid starvation issues. 133775891f50STrond Myklebust */ 133875891f50STrond Myklebust if (req->rq_cong) { 133975891f50STrond Myklebust xprt_clear_congestion_window_wait(xprt); 134075891f50STrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 134175891f50STrond Myklebust if (pos->rq_cong) 134275891f50STrond Myklebust continue; 134375891f50STrond Myklebust /* Note: req is added _before_ pos */ 134475891f50STrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 134575891f50STrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 134675891f50STrond Myklebust goto out; 134775891f50STrond Myklebust } 134886aeee0eSTrond Myklebust } else if (RPC_IS_SWAPPER(task)) { 134986aeee0eSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 135086aeee0eSTrond Myklebust if (pos->rq_cong || pos->rq_bytes_sent) 135186aeee0eSTrond Myklebust continue; 135286aeee0eSTrond Myklebust if (RPC_IS_SWAPPER(pos->rq_task)) 135386aeee0eSTrond Myklebust continue; 135486aeee0eSTrond Myklebust /* Note: req is added _before_ pos */ 135586aeee0eSTrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 135686aeee0eSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 135786aeee0eSTrond Myklebust goto out; 135886aeee0eSTrond Myklebust } 1359deaa5c96SChuck Lever } else if (!req->rq_seqno) { 1360918f3c1fSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 1361918f3c1fSTrond Myklebust if (pos->rq_task->tk_owner != task->tk_owner) 1362918f3c1fSTrond Myklebust continue; 1363918f3c1fSTrond Myklebust list_add_tail(&req->rq_xmit2, &pos->rq_xmit2); 1364918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit); 1365918f3c1fSTrond Myklebust goto out; 1366918f3c1fSTrond Myklebust } 136775891f50STrond Myklebust } 1368944b0429STrond Myklebust list_add_tail(&req->rq_xmit, &xprt->xmit_queue); 1369918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 1370918f3c1fSTrond Myklebust out: 1371d737e5d4STrond Myklebust atomic_long_inc(&xprt->xmit_queuelen); 1372944b0429STrond Myklebust set_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1373944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1374944b0429STrond Myklebust } 1375944b0429STrond Myklebust } 1376944b0429STrond Myklebust 1377944b0429STrond Myklebust /** 1378944b0429STrond Myklebust * xprt_request_dequeue_transmit_locked - remove a task from the transmission queue 1379944b0429STrond Myklebust * @task: pointer to rpc_task 1380944b0429STrond Myklebust * 1381944b0429STrond Myklebust * Remove a task from the transmission queue 1382944b0429STrond Myklebust * Caller must hold xprt->queue_lock 1383944b0429STrond Myklebust */ 1384944b0429STrond Myklebust static void 1385944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(struct rpc_task *task) 1386944b0429STrond Myklebust { 1387918f3c1fSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1388918f3c1fSTrond Myklebust 1389918f3c1fSTrond Myklebust if (!test_and_clear_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 1390918f3c1fSTrond Myklebust return; 1391918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit)) { 1392918f3c1fSTrond Myklebust list_del(&req->rq_xmit); 1393918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit2)) { 1394918f3c1fSTrond Myklebust struct rpc_rqst *next = list_first_entry(&req->rq_xmit2, 1395918f3c1fSTrond Myklebust struct rpc_rqst, rq_xmit2); 1396918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1397918f3c1fSTrond Myklebust list_add_tail(&next->rq_xmit, &next->rq_xprt->xmit_queue); 1398918f3c1fSTrond Myklebust } 1399918f3c1fSTrond Myklebust } else 1400918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1401d737e5d4STrond Myklebust atomic_long_dec(&req->rq_xprt->xmit_queuelen); 1402944b0429STrond Myklebust } 1403944b0429STrond Myklebust 1404944b0429STrond Myklebust /** 1405944b0429STrond Myklebust * xprt_request_dequeue_transmit - remove a task from the transmission queue 1406944b0429STrond Myklebust * @task: pointer to rpc_task 1407944b0429STrond Myklebust * 1408944b0429STrond Myklebust * Remove a task from the transmission queue 1409944b0429STrond Myklebust */ 1410944b0429STrond Myklebust static void 1411944b0429STrond Myklebust xprt_request_dequeue_transmit(struct rpc_task *task) 1412944b0429STrond Myklebust { 1413944b0429STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1414944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1415944b0429STrond Myklebust 1416944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 1417944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1418944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1419944b0429STrond Myklebust } 1420944b0429STrond Myklebust 14217f3a1d1eSTrond Myklebust /** 1422cc204d01STrond Myklebust * xprt_request_dequeue_xprt - remove a task from the transmit+receive queue 1423cc204d01STrond Myklebust * @task: pointer to rpc_task 1424cc204d01STrond Myklebust * 1425cc204d01STrond Myklebust * Remove a task from the transmit and receive queues, and ensure that 1426cc204d01STrond Myklebust * it is not pinned by the receive work item. 1427cc204d01STrond Myklebust */ 1428cc204d01STrond Myklebust void 1429cc204d01STrond Myklebust xprt_request_dequeue_xprt(struct rpc_task *task) 1430cc204d01STrond Myklebust { 1431cc204d01STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1432cc204d01STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1433cc204d01STrond Myklebust 1434cc204d01STrond Myklebust if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) || 1435cc204d01STrond Myklebust test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || 1436cc204d01STrond Myklebust xprt_is_pinned_rqst(req)) { 1437cc204d01STrond Myklebust spin_lock(&xprt->queue_lock); 1438cc204d01STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1439cc204d01STrond Myklebust xprt_request_dequeue_receive_locked(task); 1440cc204d01STrond Myklebust while (xprt_is_pinned_rqst(req)) { 1441cc204d01STrond Myklebust set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1442cc204d01STrond Myklebust spin_unlock(&xprt->queue_lock); 1443cc204d01STrond Myklebust xprt_wait_on_pinned_rqst(req); 1444cc204d01STrond Myklebust spin_lock(&xprt->queue_lock); 1445cc204d01STrond Myklebust clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1446cc204d01STrond Myklebust } 1447cc204d01STrond Myklebust spin_unlock(&xprt->queue_lock); 1448cc204d01STrond Myklebust } 1449cc204d01STrond Myklebust } 1450cc204d01STrond Myklebust 1451cc204d01STrond Myklebust /** 14529d96acbcSTrond Myklebust * xprt_request_prepare - prepare an encoded request for transport 14539d96acbcSTrond Myklebust * @req: pointer to rpc_rqst 14549d96acbcSTrond Myklebust * 14559d96acbcSTrond Myklebust * Calls into the transport layer to do whatever is needed to prepare 14569d96acbcSTrond Myklebust * the request for transmission or receive. 14579d96acbcSTrond Myklebust */ 14589d96acbcSTrond Myklebust void 14599d96acbcSTrond Myklebust xprt_request_prepare(struct rpc_rqst *req) 14609d96acbcSTrond Myklebust { 14619d96acbcSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 14629d96acbcSTrond Myklebust 14639d96acbcSTrond Myklebust if (xprt->ops->prepare_request) 14649d96acbcSTrond Myklebust xprt->ops->prepare_request(req); 14659d96acbcSTrond Myklebust } 14669d96acbcSTrond Myklebust 14679d96acbcSTrond Myklebust /** 1468762e4e67STrond Myklebust * xprt_request_need_retransmit - Test if a task needs retransmission 1469762e4e67STrond Myklebust * @task: pointer to rpc_task 1470762e4e67STrond Myklebust * 1471762e4e67STrond Myklebust * Test for whether a connection breakage requires the task to retransmit 1472762e4e67STrond Myklebust */ 1473762e4e67STrond Myklebust bool 1474762e4e67STrond Myklebust xprt_request_need_retransmit(struct rpc_task *task) 1475762e4e67STrond Myklebust { 1476762e4e67STrond Myklebust return xprt_request_retransmit_after_disconnect(task); 1477762e4e67STrond Myklebust } 1478762e4e67STrond Myklebust 1479762e4e67STrond Myklebust /** 14809903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 14819903cd1cSChuck Lever * @task: RPC task about to send a request 14829903cd1cSChuck Lever * 14831da177e4SLinus Torvalds */ 148490051ea7STrond Myklebust bool xprt_prepare_transmit(struct rpc_task *task) 14851da177e4SLinus Torvalds { 14861da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 14871da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 14881da177e4SLinus Torvalds 14895f2f6bd9STrond Myklebust if (!xprt_lock_write(xprt, task)) { 14905f2f6bd9STrond Myklebust /* Race breaker: someone may have transmitted us */ 1491944b0429STrond Myklebust if (!test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 14925f2f6bd9STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, 14935f2f6bd9STrond Myklebust task, 0); 14945f2f6bd9STrond Myklebust return false; 14955f2f6bd9STrond Myklebust 14968a19a0b6STrond Myklebust } 14975f2f6bd9STrond Myklebust return true; 14981da177e4SLinus Torvalds } 14991da177e4SLinus Torvalds 1500e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 15015e5ce5beSTrond Myklebust { 15027638e0bfSChuck Lever struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 15037638e0bfSChuck Lever 15047638e0bfSChuck Lever xprt_inject_disconnect(xprt); 15057638e0bfSChuck Lever xprt_release_write(xprt, task); 15065e5ce5beSTrond Myklebust } 15075e5ce5beSTrond Myklebust 15089903cd1cSChuck Lever /** 150989f90fe1STrond Myklebust * xprt_request_transmit - send an RPC request on a transport 151089f90fe1STrond Myklebust * @req: pointer to request to transmit 151189f90fe1STrond Myklebust * @snd_task: RPC task that owns the transport lock 15129903cd1cSChuck Lever * 151389f90fe1STrond Myklebust * This performs the transmission of a single request. 151489f90fe1STrond Myklebust * Note that if the request is not the same as snd_task, then it 151589f90fe1STrond Myklebust * does need to be pinned. 151689f90fe1STrond Myklebust * Returns '0' on success. 15179903cd1cSChuck Lever */ 151889f90fe1STrond Myklebust static int 151989f90fe1STrond Myklebust xprt_request_transmit(struct rpc_rqst *req, struct rpc_task *snd_task) 15201da177e4SLinus Torvalds { 15211da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 152289f90fe1STrond Myklebust struct rpc_task *task = req->rq_task; 152390d91b0cSTrond Myklebust unsigned int connect_cookie; 1524dcbbeda8STrond Myklebust int is_retrans = RPC_WAS_SENT(task); 1525ff699ea8SChuck Lever int status; 15261da177e4SLinus Torvalds 1527edc81dcdSTrond Myklebust if (!req->rq_bytes_sent) { 152889f90fe1STrond Myklebust if (xprt_request_data_received(task)) { 152989f90fe1STrond Myklebust status = 0; 1530944b0429STrond Myklebust goto out_dequeue; 153189f90fe1STrond Myklebust } 15323021a5bbSTrond Myklebust /* Verify that our message lies in the RPCSEC_GSS window */ 1533edc81dcdSTrond Myklebust if (rpcauth_xmit_need_reencode(task)) { 153489f90fe1STrond Myklebust status = -EBADMSG; 1535944b0429STrond Myklebust goto out_dequeue; 15363021a5bbSTrond Myklebust } 1537ae67bd38STrond Myklebust if (RPC_SIGNALLED(task)) { 1538ae67bd38STrond Myklebust status = -ERESTARTSYS; 1539ae67bd38STrond Myklebust goto out_dequeue; 1540ae67bd38STrond Myklebust } 15411da177e4SLinus Torvalds } 15421da177e4SLinus Torvalds 1543dcbbeda8STrond Myklebust /* 1544dcbbeda8STrond Myklebust * Update req->rq_ntrans before transmitting to avoid races with 1545dcbbeda8STrond Myklebust * xprt_update_rtt(), which needs to know that it is recording a 1546dcbbeda8STrond Myklebust * reply to the first transmission. 1547dcbbeda8STrond Myklebust */ 1548dcbbeda8STrond Myklebust req->rq_ntrans++; 1549dcbbeda8STrond Myklebust 1550c509f15aSChuck Lever trace_rpc_xdr_sendto(task, &req->rq_snd_buf); 155190d91b0cSTrond Myklebust connect_cookie = xprt->connect_cookie; 1552adfa7144STrond Myklebust status = xprt->ops->send_request(req); 1553c8485e4dSTrond Myklebust if (status != 0) { 1554dcbbeda8STrond Myklebust req->rq_ntrans--; 15550c77668dSChuck Lever trace_xprt_transmit(req, status); 155689f90fe1STrond Myklebust return status; 1557c8485e4dSTrond Myklebust } 15587ebbbc6eSTrond Myklebust 1559e936a597SChuck Lever if (is_retrans) { 1560dcbbeda8STrond Myklebust task->tk_client->cl_stats->rpcretrans++; 1561e936a597SChuck Lever trace_xprt_retransmit(req); 1562e936a597SChuck Lever } 1563dcbbeda8STrond Myklebust 15644a068258SChuck Lever xprt_inject_disconnect(xprt); 1565c8485e4dSTrond Myklebust 1566468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 1567b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 1568262ca07dSChuck Lever 1569262ca07dSChuck Lever xprt->stat.sends++; 1570262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 1571262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 157215a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 157315a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 1574b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 157590d91b0cSTrond Myklebust 157690d91b0cSTrond Myklebust req->rq_connect_cookie = connect_cookie; 1577944b0429STrond Myklebust out_dequeue: 15780c77668dSChuck Lever trace_xprt_transmit(req, status); 1579944b0429STrond Myklebust xprt_request_dequeue_transmit(task); 158089f90fe1STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, task, status); 158189f90fe1STrond Myklebust return status; 158289f90fe1STrond Myklebust } 158389f90fe1STrond Myklebust 158489f90fe1STrond Myklebust /** 158589f90fe1STrond Myklebust * xprt_transmit - send an RPC request on a transport 158689f90fe1STrond Myklebust * @task: controlling RPC task 158789f90fe1STrond Myklebust * 158889f90fe1STrond Myklebust * Attempts to drain the transmit queue. On exit, either the transport 158989f90fe1STrond Myklebust * signalled an error that needs to be handled before transmission can 159089f90fe1STrond Myklebust * resume, or @task finished transmitting, and detected that it already 159189f90fe1STrond Myklebust * received a reply. 159289f90fe1STrond Myklebust */ 159389f90fe1STrond Myklebust void 159489f90fe1STrond Myklebust xprt_transmit(struct rpc_task *task) 159589f90fe1STrond Myklebust { 159689f90fe1STrond Myklebust struct rpc_rqst *next, *req = task->tk_rqstp; 159789f90fe1STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 15986f9f1728SChuck Lever int counter, status; 159989f90fe1STrond Myklebust 160089f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 16016f9f1728SChuck Lever counter = 0; 160289f90fe1STrond Myklebust while (!list_empty(&xprt->xmit_queue)) { 16036f9f1728SChuck Lever if (++counter == 20) 16046f9f1728SChuck Lever break; 160589f90fe1STrond Myklebust next = list_first_entry(&xprt->xmit_queue, 160689f90fe1STrond Myklebust struct rpc_rqst, rq_xmit); 160789f90fe1STrond Myklebust xprt_pin_rqst(next); 160889f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 160989f90fe1STrond Myklebust status = xprt_request_transmit(next, task); 161089f90fe1STrond Myklebust if (status == -EBADMSG && next != req) 161189f90fe1STrond Myklebust status = 0; 161289f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 161389f90fe1STrond Myklebust xprt_unpin_rqst(next); 161489f90fe1STrond Myklebust if (status == 0) { 161589f90fe1STrond Myklebust if (!xprt_request_data_received(task) || 161689f90fe1STrond Myklebust test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 161789f90fe1STrond Myklebust continue; 1618c544577dSTrond Myklebust } else if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 161989f90fe1STrond Myklebust task->tk_status = status; 162089f90fe1STrond Myklebust break; 162189f90fe1STrond Myklebust } 162289f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 16231da177e4SLinus Torvalds } 16241da177e4SLinus Torvalds 1625e86be3a0STrond Myklebust static void xprt_complete_request_init(struct rpc_task *task) 1626e86be3a0STrond Myklebust { 1627e86be3a0STrond Myklebust if (task->tk_rqstp) 1628e86be3a0STrond Myklebust xprt_request_init(task); 1629e86be3a0STrond Myklebust } 1630e86be3a0STrond Myklebust 1631e86be3a0STrond Myklebust void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) 1632ba60eb25STrond Myklebust { 1633ba60eb25STrond Myklebust set_bit(XPRT_CONGESTED, &xprt->state); 1634e86be3a0STrond Myklebust rpc_sleep_on(&xprt->backlog, task, xprt_complete_request_init); 1635ba60eb25STrond Myklebust } 1636e86be3a0STrond Myklebust EXPORT_SYMBOL_GPL(xprt_add_backlog); 1637ba60eb25STrond Myklebust 1638e877a88dSNeilBrown static bool __xprt_set_rq(struct rpc_task *task, void *data) 1639ba60eb25STrond Myklebust { 1640e877a88dSNeilBrown struct rpc_rqst *req = data; 1641e877a88dSNeilBrown 1642e877a88dSNeilBrown if (task->tk_rqstp == NULL) { 1643e877a88dSNeilBrown memset(req, 0, sizeof(*req)); /* mark unused */ 1644e877a88dSNeilBrown task->tk_rqstp = req; 1645e877a88dSNeilBrown return true; 1646e877a88dSNeilBrown } 1647e877a88dSNeilBrown return false; 1648e877a88dSNeilBrown } 1649e877a88dSNeilBrown 1650e86be3a0STrond Myklebust bool xprt_wake_up_backlog(struct rpc_xprt *xprt, struct rpc_rqst *req) 1651e877a88dSNeilBrown { 1652e877a88dSNeilBrown if (rpc_wake_up_first(&xprt->backlog, __xprt_set_rq, req) == NULL) { 1653ba60eb25STrond Myklebust clear_bit(XPRT_CONGESTED, &xprt->state); 1654e877a88dSNeilBrown return false; 1655e877a88dSNeilBrown } 1656e877a88dSNeilBrown return true; 1657ba60eb25STrond Myklebust } 1658e86be3a0STrond Myklebust EXPORT_SYMBOL_GPL(xprt_wake_up_backlog); 1659ba60eb25STrond Myklebust 1660ba60eb25STrond Myklebust static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) 1661ba60eb25STrond Myklebust { 1662ba60eb25STrond Myklebust bool ret = false; 1663ba60eb25STrond Myklebust 1664ba60eb25STrond Myklebust if (!test_bit(XPRT_CONGESTED, &xprt->state)) 1665ba60eb25STrond Myklebust goto out; 1666ba60eb25STrond Myklebust spin_lock(&xprt->reserve_lock); 1667ba60eb25STrond Myklebust if (test_bit(XPRT_CONGESTED, &xprt->state)) { 1668e86be3a0STrond Myklebust xprt_add_backlog(xprt, task); 1669ba60eb25STrond Myklebust ret = true; 1670ba60eb25STrond Myklebust } 1671ba60eb25STrond Myklebust spin_unlock(&xprt->reserve_lock); 1672ba60eb25STrond Myklebust out: 1673ba60eb25STrond Myklebust return ret; 1674ba60eb25STrond Myklebust } 1675ba60eb25STrond Myklebust 167692ea011fSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt) 1677d9ba131dSTrond Myklebust { 1678d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 1679d9ba131dSTrond Myklebust 1680ff699ea8SChuck Lever if (xprt->num_reqs >= xprt->max_reqs) 1681d9ba131dSTrond Myklebust goto out; 1682ff699ea8SChuck Lever ++xprt->num_reqs; 168392ea011fSTrond Myklebust spin_unlock(&xprt->reserve_lock); 168492ea011fSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_NOFS); 168592ea011fSTrond Myklebust spin_lock(&xprt->reserve_lock); 1686d9ba131dSTrond Myklebust if (req != NULL) 1687d9ba131dSTrond Myklebust goto out; 1688ff699ea8SChuck Lever --xprt->num_reqs; 1689d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 1690d9ba131dSTrond Myklebust out: 1691d9ba131dSTrond Myklebust return req; 1692d9ba131dSTrond Myklebust } 1693d9ba131dSTrond Myklebust 1694d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1695d9ba131dSTrond Myklebust { 1696ff699ea8SChuck Lever if (xprt->num_reqs > xprt->min_reqs) { 1697ff699ea8SChuck Lever --xprt->num_reqs; 1698d9ba131dSTrond Myklebust kfree(req); 1699d9ba131dSTrond Myklebust return true; 1700d9ba131dSTrond Myklebust } 1701d9ba131dSTrond Myklebust return false; 1702d9ba131dSTrond Myklebust } 1703d9ba131dSTrond Myklebust 1704f39c1bfbSTrond Myklebust void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 17051da177e4SLinus Torvalds { 1706d9ba131dSTrond Myklebust struct rpc_rqst *req; 17071da177e4SLinus Torvalds 1708f39c1bfbSTrond Myklebust spin_lock(&xprt->reserve_lock); 17091da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 1710d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 1711d9ba131dSTrond Myklebust list_del(&req->rq_list); 1712d9ba131dSTrond Myklebust goto out_init_req; 1713d9ba131dSTrond Myklebust } 171492ea011fSTrond Myklebust req = xprt_dynamic_alloc_slot(xprt); 1715d9ba131dSTrond Myklebust if (!IS_ERR(req)) 1716d9ba131dSTrond Myklebust goto out_init_req; 1717d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 1718d9ba131dSTrond Myklebust case -ENOMEM: 1719d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 1720d9ba131dSTrond Myklebust "failed! Retrying\n"); 17211afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 1722d9ba131dSTrond Myklebust break; 1723d9ba131dSTrond Myklebust case -EAGAIN: 1724ba60eb25STrond Myklebust xprt_add_backlog(xprt, task); 1725d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 1726df561f66SGustavo A. R. Silva fallthrough; 17271afeaf5cSTrond Myklebust default: 1728d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 17291afeaf5cSTrond Myklebust } 1730f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 1731d9ba131dSTrond Myklebust return; 1732d9ba131dSTrond Myklebust out_init_req: 1733ff699ea8SChuck Lever xprt->stat.max_slots = max_t(unsigned int, xprt->stat.max_slots, 1734ff699ea8SChuck Lever xprt->num_reqs); 173537ac86c3SChuck Lever spin_unlock(&xprt->reserve_lock); 173637ac86c3SChuck Lever 1737d9ba131dSTrond Myklebust task->tk_status = 0; 17381da177e4SLinus Torvalds task->tk_rqstp = req; 17391da177e4SLinus Torvalds } 1740f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_alloc_slot); 1741f39c1bfbSTrond Myklebust 1742a9cde23aSChuck Lever void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1743ee5ebe85STrond Myklebust { 1744ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1745e877a88dSNeilBrown if (!xprt_wake_up_backlog(xprt, req) && 1746e877a88dSNeilBrown !xprt_dynamic_free_slot(xprt, req)) { 1747c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1748ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1749c25573b5STrond Myklebust } 1750ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1751ee5ebe85STrond Myklebust } 1752a9cde23aSChuck Lever EXPORT_SYMBOL_GPL(xprt_free_slot); 1753ee5ebe85STrond Myklebust 175421de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 175521de0a95STrond Myklebust { 175621de0a95STrond Myklebust struct rpc_rqst *req; 175721de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 175821de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 175921de0a95STrond Myklebust list_del(&req->rq_list); 176021de0a95STrond Myklebust kfree(req); 176121de0a95STrond Myklebust } 176221de0a95STrond Myklebust } 176321de0a95STrond Myklebust 1764572caba4SOlga Kornievskaia static DEFINE_IDA(rpc_xprt_ids); 1765572caba4SOlga Kornievskaia 1766572caba4SOlga Kornievskaia void xprt_cleanup_ids(void) 1767572caba4SOlga Kornievskaia { 1768572caba4SOlga Kornievskaia ida_destroy(&rpc_xprt_ids); 1769572caba4SOlga Kornievskaia } 1770572caba4SOlga Kornievskaia 1771572caba4SOlga Kornievskaia static int xprt_alloc_id(struct rpc_xprt *xprt) 1772572caba4SOlga Kornievskaia { 1773572caba4SOlga Kornievskaia int id; 1774572caba4SOlga Kornievskaia 1775572caba4SOlga Kornievskaia id = ida_simple_get(&rpc_xprt_ids, 0, 0, GFP_KERNEL); 1776572caba4SOlga Kornievskaia if (id < 0) 1777572caba4SOlga Kornievskaia return id; 1778572caba4SOlga Kornievskaia 1779572caba4SOlga Kornievskaia xprt->id = id; 1780572caba4SOlga Kornievskaia return 0; 1781572caba4SOlga Kornievskaia } 1782572caba4SOlga Kornievskaia 1783572caba4SOlga Kornievskaia static void xprt_free_id(struct rpc_xprt *xprt) 1784572caba4SOlga Kornievskaia { 1785572caba4SOlga Kornievskaia ida_simple_remove(&rpc_xprt_ids, xprt->id); 1786572caba4SOlga Kornievskaia } 1787572caba4SOlga Kornievskaia 1788d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1789d9ba131dSTrond Myklebust unsigned int num_prealloc, 1790d9ba131dSTrond Myklebust unsigned int max_alloc) 1791bd1722d4SPavel Emelyanov { 1792bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 179321de0a95STrond Myklebust struct rpc_rqst *req; 179421de0a95STrond Myklebust int i; 1795bd1722d4SPavel Emelyanov 1796bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1797bd1722d4SPavel Emelyanov if (xprt == NULL) 1798bd1722d4SPavel Emelyanov goto out; 1799bd1722d4SPavel Emelyanov 1800572caba4SOlga Kornievskaia xprt_alloc_id(xprt); 180121de0a95STrond Myklebust xprt_init(xprt, net); 180221de0a95STrond Myklebust 180321de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 180421de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 180521de0a95STrond Myklebust if (!req) 18068313164cSwangweidong goto out_free; 180721de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 180821de0a95STrond Myklebust } 1809d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1810d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1811d9ba131dSTrond Myklebust else 181221de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1813d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1814ff699ea8SChuck Lever xprt->num_reqs = num_prealloc; 1815bd1722d4SPavel Emelyanov 1816bd1722d4SPavel Emelyanov return xprt; 1817bd1722d4SPavel Emelyanov 1818bd1722d4SPavel Emelyanov out_free: 181921de0a95STrond Myklebust xprt_free(xprt); 1820bd1722d4SPavel Emelyanov out: 1821bd1722d4SPavel Emelyanov return NULL; 1822bd1722d4SPavel Emelyanov } 1823bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1824bd1722d4SPavel Emelyanov 1825e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1826e204e621SPavel Emelyanov { 182737aa2133SPavel Emelyanov put_net(xprt->xprt_net); 182821de0a95STrond Myklebust xprt_free_all_slots(xprt); 1829572caba4SOlga Kornievskaia xprt_free_id(xprt); 1830587bc725SOlga Kornievskaia rpc_sysfs_xprt_destroy(xprt); 1831fda1bfefSTrond Myklebust kfree_rcu(xprt, rcu); 1832e204e621SPavel Emelyanov } 1833e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1834e204e621SPavel Emelyanov 1835902c5887STrond Myklebust static void 1836902c5887STrond Myklebust xprt_init_connect_cookie(struct rpc_rqst *req, struct rpc_xprt *xprt) 1837902c5887STrond Myklebust { 1838902c5887STrond Myklebust req->rq_connect_cookie = xprt_connect_cookie(xprt) - 1; 1839902c5887STrond Myklebust } 1840902c5887STrond Myklebust 18419dc6edcfSTrond Myklebust static __be32 18429dc6edcfSTrond Myklebust xprt_alloc_xid(struct rpc_xprt *xprt) 18439dc6edcfSTrond Myklebust { 18449dc6edcfSTrond Myklebust __be32 xid; 18459dc6edcfSTrond Myklebust 18469dc6edcfSTrond Myklebust spin_lock(&xprt->reserve_lock); 18479dc6edcfSTrond Myklebust xid = (__force __be32)xprt->xid++; 18489dc6edcfSTrond Myklebust spin_unlock(&xprt->reserve_lock); 18499dc6edcfSTrond Myklebust return xid; 18509dc6edcfSTrond Myklebust } 18519dc6edcfSTrond Myklebust 18529dc6edcfSTrond Myklebust static void 18539dc6edcfSTrond Myklebust xprt_init_xid(struct rpc_xprt *xprt) 18549dc6edcfSTrond Myklebust { 18559dc6edcfSTrond Myklebust xprt->xid = prandom_u32(); 18569dc6edcfSTrond Myklebust } 18579dc6edcfSTrond Myklebust 18589dc6edcfSTrond Myklebust static void 18599dc6edcfSTrond Myklebust xprt_request_init(struct rpc_task *task) 18609dc6edcfSTrond Myklebust { 18619dc6edcfSTrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 18629dc6edcfSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 18639dc6edcfSTrond Myklebust 18649dc6edcfSTrond Myklebust req->rq_task = task; 18659dc6edcfSTrond Myklebust req->rq_xprt = xprt; 18669dc6edcfSTrond Myklebust req->rq_buffer = NULL; 18679dc6edcfSTrond Myklebust req->rq_xid = xprt_alloc_xid(xprt); 1868902c5887STrond Myklebust xprt_init_connect_cookie(req, xprt); 18699dc6edcfSTrond Myklebust req->rq_snd_buf.len = 0; 18709dc6edcfSTrond Myklebust req->rq_snd_buf.buflen = 0; 18719dc6edcfSTrond Myklebust req->rq_rcv_buf.len = 0; 18729dc6edcfSTrond Myklebust req->rq_rcv_buf.buflen = 0; 187371700bb9STrond Myklebust req->rq_snd_buf.bvec = NULL; 187471700bb9STrond Myklebust req->rq_rcv_buf.bvec = NULL; 18759dc6edcfSTrond Myklebust req->rq_release_snd_buf = NULL; 1876da953063STrond Myklebust xprt_init_majortimeo(task, req); 187709d2ba0cSChuck Lever 187809d2ba0cSChuck Lever trace_xprt_reserve(req); 18799dc6edcfSTrond Myklebust } 18809dc6edcfSTrond Myklebust 18819dc6edcfSTrond Myklebust static void 18829dc6edcfSTrond Myklebust xprt_do_reserve(struct rpc_xprt *xprt, struct rpc_task *task) 18839dc6edcfSTrond Myklebust { 18849dc6edcfSTrond Myklebust xprt->ops->alloc_slot(xprt, task); 18859dc6edcfSTrond Myklebust if (task->tk_rqstp != NULL) 18869dc6edcfSTrond Myklebust xprt_request_init(task); 18879dc6edcfSTrond Myklebust } 18889dc6edcfSTrond Myklebust 18899903cd1cSChuck Lever /** 18909903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 18919903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 18929903cd1cSChuck Lever * 1893ba60eb25STrond Myklebust * If the transport is marked as being congested, or if no more 1894ba60eb25STrond Myklebust * slots are available, place the task on the transport's 18959903cd1cSChuck Lever * backlog queue. 18969903cd1cSChuck Lever */ 18979903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 18981da177e4SLinus Torvalds { 1899fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 19001da177e4SLinus Torvalds 190143cedbf0STrond Myklebust task->tk_status = 0; 190243cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 190343cedbf0STrond Myklebust return; 190443cedbf0STrond Myklebust 190543cedbf0STrond Myklebust task->tk_status = -EAGAIN; 1906ba60eb25STrond Myklebust if (!xprt_throttle_congested(xprt, task)) 19079dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 1908ba60eb25STrond Myklebust } 1909ba60eb25STrond Myklebust 1910ba60eb25STrond Myklebust /** 1911ba60eb25STrond Myklebust * xprt_retry_reserve - allocate an RPC request slot 1912ba60eb25STrond Myklebust * @task: RPC task requesting a slot allocation 1913ba60eb25STrond Myklebust * 1914ba60eb25STrond Myklebust * If no more slots are available, place the task on the transport's 1915ba60eb25STrond Myklebust * backlog queue. 1916ba60eb25STrond Myklebust * Note that the only difference with xprt_reserve is that we now 1917ba60eb25STrond Myklebust * ignore the value of the XPRT_CONGESTED flag. 1918ba60eb25STrond Myklebust */ 1919ba60eb25STrond Myklebust void xprt_retry_reserve(struct rpc_task *task) 1920ba60eb25STrond Myklebust { 1921fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 1922ba60eb25STrond Myklebust 1923ba60eb25STrond Myklebust task->tk_status = 0; 1924e86be3a0STrond Myklebust if (task->tk_rqstp != NULL) 1925ba60eb25STrond Myklebust return; 1926ba60eb25STrond Myklebust 1927ba60eb25STrond Myklebust task->tk_status = -EAGAIN; 19289dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 19291da177e4SLinus Torvalds } 19301da177e4SLinus Torvalds 19319903cd1cSChuck Lever /** 19329903cd1cSChuck Lever * xprt_release - release an RPC request slot 19339903cd1cSChuck Lever * @task: task which is finished with the slot 19349903cd1cSChuck Lever * 19351da177e4SLinus Torvalds */ 19369903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 19371da177e4SLinus Torvalds { 193855ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 193987ed5003STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 19401da177e4SLinus Torvalds 194187ed5003STrond Myklebust if (req == NULL) { 194287ed5003STrond Myklebust if (task->tk_client) { 1943fb43d172STrond Myklebust xprt = task->tk_xprt; 194487ed5003STrond Myklebust xprt_release_write(xprt, task); 194587ed5003STrond Myklebust } 19461da177e4SLinus Torvalds return; 194787ed5003STrond Myklebust } 194855ae1aabSRicardo Labiaga 194955ae1aabSRicardo Labiaga xprt = req->rq_xprt; 1950cc204d01STrond Myklebust xprt_request_dequeue_xprt(task); 1951b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 195249e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1953a58dd398SChuck Lever if (xprt->ops->release_request) 1954a58dd398SChuck Lever xprt->ops->release_request(task); 1955ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 1956b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 1957ee5ebe85STrond Myklebust if (req->rq_buffer) 19583435c74aSChuck Lever xprt->ops->buf_free(task); 19599d96acbcSTrond Myklebust xdr_free_bvec(&req->rq_rcv_buf); 19600472e476STrond Myklebust xdr_free_bvec(&req->rq_snd_buf); 1961a17c2153STrond Myklebust if (req->rq_cred != NULL) 1962a17c2153STrond Myklebust put_rpccred(req->rq_cred); 1963ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1964ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 196555ae1aabSRicardo Labiaga 1966e877a88dSNeilBrown task->tk_rqstp = NULL; 1967ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1968a9cde23aSChuck Lever xprt->ops->free_slot(xprt, req); 1969ee5ebe85STrond Myklebust else 1970c9acb42eSTrond Myklebust xprt_free_bc_request(req); 19711da177e4SLinus Torvalds } 19721da177e4SLinus Torvalds 1973902c5887STrond Myklebust #ifdef CONFIG_SUNRPC_BACKCHANNEL 1974902c5887STrond Myklebust void 1975902c5887STrond Myklebust xprt_init_bc_request(struct rpc_rqst *req, struct rpc_task *task) 1976902c5887STrond Myklebust { 1977902c5887STrond Myklebust struct xdr_buf *xbufp = &req->rq_snd_buf; 1978902c5887STrond Myklebust 1979902c5887STrond Myklebust task->tk_rqstp = req; 1980902c5887STrond Myklebust req->rq_task = task; 1981902c5887STrond Myklebust xprt_init_connect_cookie(req, req->rq_xprt); 1982902c5887STrond Myklebust /* 1983902c5887STrond Myklebust * Set up the xdr_buf length. 1984902c5887STrond Myklebust * This also indicates that the buffer is XDR encoded already. 1985902c5887STrond Myklebust */ 1986902c5887STrond Myklebust xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1987902c5887STrond Myklebust xbufp->tail[0].iov_len; 1988902c5887STrond Myklebust } 1989902c5887STrond Myklebust #endif 1990902c5887STrond Myklebust 199121de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 1992c2866763SChuck Lever { 199330c5116bSTrond Myklebust kref_init(&xprt->kref); 1994c2866763SChuck Lever 1995c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 1996c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 199775c84151STrond Myklebust spin_lock_init(&xprt->queue_lock); 1998c2866763SChuck Lever 1999c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 200095f7691dSTrond Myklebust xprt->recv_queue = RB_ROOT; 2001944b0429STrond Myklebust INIT_LIST_HEAD(&xprt->xmit_queue); 20029e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2003f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 2004f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 20059e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 200680b14d5eSTrond Myklebust INIT_LIST_HEAD(&xprt->xprt_switch); 2007f9acac1aSRicardo Labiaga 2008c2866763SChuck Lever xprt->last_used = jiffies; 2009c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 2010a509050bSChuck Lever xprt->bind_index = 0; 2011c2866763SChuck Lever 2012c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 2013c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 201479c99152STrond Myklebust rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 2015c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 2016c2866763SChuck Lever 2017c2866763SChuck Lever xprt_init_xid(xprt); 2018c2866763SChuck Lever 201921de0a95STrond Myklebust xprt->xprt_net = get_net(net); 20208d9266ffSTrond Myklebust } 20218d9266ffSTrond Myklebust 20228d9266ffSTrond Myklebust /** 20238d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 20248d9266ffSTrond Myklebust * @args: rpc transport creation arguments 20258d9266ffSTrond Myklebust * 20268d9266ffSTrond Myklebust */ 20278d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 20288d9266ffSTrond Myklebust { 20298d9266ffSTrond Myklebust struct rpc_xprt *xprt; 20309bccd264STrond Myklebust const struct xprt_class *t; 20318d9266ffSTrond Myklebust 20329bccd264STrond Myklebust t = xprt_class_find_by_ident(args->ident); 20339bccd264STrond Myklebust if (!t) { 20343c45ddf8SChuck Lever dprintk("RPC: transport (%d) not supported\n", args->ident); 20358d9266ffSTrond Myklebust return ERR_PTR(-EIO); 20369bccd264STrond Myklebust } 20378d9266ffSTrond Myklebust 20388d9266ffSTrond Myklebust xprt = t->setup(args); 20399bccd264STrond Myklebust xprt_class_release(t); 20409bccd264STrond Myklebust 2041911813d7SChuck Lever if (IS_ERR(xprt)) 204221de0a95STrond Myklebust goto out; 204333d90ac0SJ. Bruce Fields if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) 204433d90ac0SJ. Bruce Fields xprt->idle_timeout = 0; 204521de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 204621de0a95STrond Myklebust if (xprt_has_timer(xprt)) 2047502980e8SAnna Schumaker timer_setup(&xprt->timer, xprt_init_autodisconnect, 0); 204821de0a95STrond Myklebust else 2049ff861c4dSKees Cook timer_setup(&xprt->timer, NULL, 0); 20504e0038b6STrond Myklebust 20514e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 20524e0038b6STrond Myklebust xprt_destroy(xprt); 20534e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 20544e0038b6STrond Myklebust } 20554e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 20564e0038b6STrond Myklebust if (xprt->servername == NULL) { 20574e0038b6STrond Myklebust xprt_destroy(xprt); 20584e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 20594e0038b6STrond Myklebust } 20604e0038b6STrond Myklebust 20613f940098SJeff Layton rpc_xprt_debugfs_register(xprt); 2062388f0c77SJeff Layton 2063911813d7SChuck Lever trace_xprt_create(xprt); 206421de0a95STrond Myklebust out: 2065c2866763SChuck Lever return xprt; 2066c2866763SChuck Lever } 2067c2866763SChuck Lever 2068528fd354STrond Myklebust static void xprt_destroy_cb(struct work_struct *work) 2069528fd354STrond Myklebust { 2070528fd354STrond Myklebust struct rpc_xprt *xprt = 2071528fd354STrond Myklebust container_of(work, struct rpc_xprt, task_cleanup); 2072528fd354STrond Myklebust 2073911813d7SChuck Lever trace_xprt_destroy(xprt); 2074911813d7SChuck Lever 2075528fd354STrond Myklebust rpc_xprt_debugfs_unregister(xprt); 2076528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 2077528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 2078528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 2079528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 2080528fd354STrond Myklebust kfree(xprt->servername); 2081528fd354STrond Myklebust /* 2082669996adSTrond Myklebust * Destroy any existing back channel 2083669996adSTrond Myklebust */ 2084669996adSTrond Myklebust xprt_destroy_backchannel(xprt, UINT_MAX); 2085669996adSTrond Myklebust 2086669996adSTrond Myklebust /* 2087528fd354STrond Myklebust * Tear down transport state and free the rpc_xprt 2088528fd354STrond Myklebust */ 2089528fd354STrond Myklebust xprt->ops->destroy(xprt); 2090528fd354STrond Myklebust } 2091528fd354STrond Myklebust 20929903cd1cSChuck Lever /** 20939903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 2094a8de240aSTrond Myklebust * @xprt: transport to destroy 20959903cd1cSChuck Lever * 20961da177e4SLinus Torvalds */ 2097a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 20981da177e4SLinus Torvalds { 2099528fd354STrond Myklebust /* 2100528fd354STrond Myklebust * Exclude transport connect/disconnect handlers and autoclose 2101528fd354STrond Myklebust */ 210279234c3dSTrond Myklebust wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); 210379234c3dSTrond Myklebust 21040065db32STrond Myklebust del_timer_sync(&xprt->timer); 2105c8541ecdSChuck Lever 2106c8541ecdSChuck Lever /* 2107528fd354STrond Myklebust * Destroy sockets etc from the system workqueue so they can 2108528fd354STrond Myklebust * safely flush receive work running on rpciod. 2109c8541ecdSChuck Lever */ 2110528fd354STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_destroy_cb); 2111528fd354STrond Myklebust schedule_work(&xprt->task_cleanup); 21126b6ca86bSTrond Myklebust } 21131da177e4SLinus Torvalds 211430c5116bSTrond Myklebust static void xprt_destroy_kref(struct kref *kref) 211530c5116bSTrond Myklebust { 211630c5116bSTrond Myklebust xprt_destroy(container_of(kref, struct rpc_xprt, kref)); 211730c5116bSTrond Myklebust } 211830c5116bSTrond Myklebust 211930c5116bSTrond Myklebust /** 212030c5116bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 212130c5116bSTrond Myklebust * @xprt: pointer to the transport 212230c5116bSTrond Myklebust * 212330c5116bSTrond Myklebust */ 212430c5116bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 212530c5116bSTrond Myklebust { 212630c5116bSTrond Myklebust if (xprt != NULL && kref_get_unless_zero(&xprt->kref)) 212730c5116bSTrond Myklebust return xprt; 212830c5116bSTrond Myklebust return NULL; 212930c5116bSTrond Myklebust } 213030c5116bSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_get); 213130c5116bSTrond Myklebust 21326b6ca86bSTrond Myklebust /** 21336b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 21346b6ca86bSTrond Myklebust * @xprt: pointer to the transport 21356b6ca86bSTrond Myklebust * 21366b6ca86bSTrond Myklebust */ 21376b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 21386b6ca86bSTrond Myklebust { 213930c5116bSTrond Myklebust if (xprt != NULL) 214030c5116bSTrond Myklebust kref_put(&xprt->kref, xprt_destroy_kref); 21416b6ca86bSTrond Myklebust } 21425d252f90SChuck Lever EXPORT_SYMBOL_GPL(xprt_put); 2143