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" 59a4ae3081SChuck 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; 24933c3214bSTrond Myklebust if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) 25033c3214bSTrond Myklebust clear_bit_unlock(XPRT_LOCKED, &xprt->state); 25133c3214bSTrond Myklebust else 252c544577dSTrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 253c544577dSTrond Myklebust } 254c544577dSTrond Myklebust 255441e3e24STom Talpey /** 25612a80469SChuck Lever * xprt_reserve_xprt - serialize write access to transports 25712a80469SChuck Lever * @task: task that is requesting access to the transport 258177c27bfSRandy Dunlap * @xprt: pointer to the target transport 25912a80469SChuck Lever * 26012a80469SChuck Lever * This prevents mixing the payload of separate requests, and prevents 26112a80469SChuck Lever * transport connects from colliding with writes. No congestion control 26212a80469SChuck Lever * is provided. 2631da177e4SLinus Torvalds */ 26443cedbf0STrond Myklebust int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 2651da177e4SLinus Torvalds { 26612a80469SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 26712a80469SChuck Lever 26812a80469SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 26912a80469SChuck Lever if (task == xprt->snd_task) 270bf7ca707SChuck Lever goto out_locked; 27112a80469SChuck Lever goto out_sleep; 27212a80469SChuck Lever } 273c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 274c544577dSTrond Myklebust goto out_unlock; 27512a80469SChuck Lever xprt->snd_task = task; 2764d4a76f3Sj223yang@asset.uwaterloo.ca 277bf7ca707SChuck Lever out_locked: 278bf7ca707SChuck Lever trace_xprt_reserve_xprt(xprt, task); 27912a80469SChuck Lever return 1; 28012a80469SChuck Lever 281c544577dSTrond Myklebust out_unlock: 282c544577dSTrond Myklebust xprt_clear_locked(xprt); 28312a80469SChuck Lever out_sleep: 28412a80469SChuck Lever task->tk_status = -EAGAIN; 2856b2e6856STrond Myklebust if (RPC_IS_SOFT(task)) 2866b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->sending, task, NULL, 2879e910bffSTrond Myklebust xprt_request_timeout(req)); 2886b2e6856STrond Myklebust else 28979c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 29012a80469SChuck Lever return 0; 29112a80469SChuck Lever } 29212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt); 29312a80469SChuck Lever 29475891f50STrond Myklebust static bool 29575891f50STrond Myklebust xprt_need_congestion_window_wait(struct rpc_xprt *xprt) 29675891f50STrond Myklebust { 29775891f50STrond Myklebust return test_bit(XPRT_CWND_WAIT, &xprt->state); 29875891f50STrond Myklebust } 29975891f50STrond Myklebust 30075891f50STrond Myklebust static void 30175891f50STrond Myklebust xprt_set_congestion_window_wait(struct rpc_xprt *xprt) 30275891f50STrond Myklebust { 30375891f50STrond Myklebust if (!list_empty(&xprt->xmit_queue)) { 30475891f50STrond Myklebust /* Peek at head of queue to see if it can make progress */ 30575891f50STrond Myklebust if (list_first_entry(&xprt->xmit_queue, struct rpc_rqst, 30675891f50STrond Myklebust rq_xmit)->rq_cong) 30775891f50STrond Myklebust return; 30875891f50STrond Myklebust } 30975891f50STrond Myklebust set_bit(XPRT_CWND_WAIT, &xprt->state); 31075891f50STrond Myklebust } 31175891f50STrond Myklebust 31275891f50STrond Myklebust static void 31375891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(struct rpc_xprt *xprt) 31475891f50STrond Myklebust { 31575891f50STrond Myklebust if (!RPCXPRT_CONGESTED(xprt)) 31675891f50STrond Myklebust clear_bit(XPRT_CWND_WAIT, &xprt->state); 31775891f50STrond Myklebust } 31875891f50STrond Myklebust 31912a80469SChuck Lever /* 32012a80469SChuck Lever * xprt_reserve_xprt_cong - serialize write access to transports 32112a80469SChuck Lever * @task: task that is requesting access to the transport 32212a80469SChuck Lever * 32312a80469SChuck Lever * Same as xprt_reserve_xprt, but Van Jacobson congestion control is 32412a80469SChuck Lever * integrated into the decision of whether a request is allowed to be 32512a80469SChuck Lever * woken up and given access to the transport. 32675891f50STrond Myklebust * Note that the lock is only granted if we know there are free slots. 32712a80469SChuck Lever */ 32843cedbf0STrond Myklebust int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 32912a80469SChuck Lever { 3301da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 3311da177e4SLinus Torvalds 3322226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { 3331da177e4SLinus Torvalds if (task == xprt->snd_task) 334bf7ca707SChuck Lever goto out_locked; 3351da177e4SLinus Torvalds goto out_sleep; 3361da177e4SLinus Torvalds } 33743cedbf0STrond Myklebust if (req == NULL) { 33843cedbf0STrond Myklebust xprt->snd_task = task; 339bf7ca707SChuck Lever goto out_locked; 34043cedbf0STrond Myklebust } 341c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 342c544577dSTrond Myklebust goto out_unlock; 34375891f50STrond Myklebust if (!xprt_need_congestion_window_wait(xprt)) { 3441da177e4SLinus Torvalds xprt->snd_task = task; 345bf7ca707SChuck Lever goto out_locked; 3461da177e4SLinus Torvalds } 347c544577dSTrond Myklebust out_unlock: 348632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 3491da177e4SLinus Torvalds out_sleep: 3501da177e4SLinus Torvalds task->tk_status = -EAGAIN; 3516b2e6856STrond Myklebust if (RPC_IS_SOFT(task)) 3526b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->sending, task, NULL, 3539e910bffSTrond Myklebust xprt_request_timeout(req)); 3546b2e6856STrond Myklebust else 35579c99152STrond Myklebust rpc_sleep_on(&xprt->sending, task, NULL); 3561da177e4SLinus Torvalds return 0; 357bf7ca707SChuck Lever out_locked: 358bf7ca707SChuck Lever trace_xprt_reserve_cong(xprt, task); 359bf7ca707SChuck Lever return 1; 3601da177e4SLinus Torvalds } 36112444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); 3621da177e4SLinus Torvalds 36312a80469SChuck Lever static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) 3641da177e4SLinus Torvalds { 3651da177e4SLinus Torvalds int retval; 3661da177e4SLinus Torvalds 367bd79bc57STrond Myklebust if (test_bit(XPRT_LOCKED, &xprt->state) && xprt->snd_task == task) 368bd79bc57STrond Myklebust return 1; 369b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 37043cedbf0STrond Myklebust retval = xprt->ops->reserve_xprt(xprt, task); 371b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 3721da177e4SLinus Torvalds return retval; 3731da177e4SLinus Torvalds } 3741da177e4SLinus Torvalds 375961a828dSTrond Myklebust static bool __xprt_lock_write_func(struct rpc_task *task, void *data) 3761da177e4SLinus Torvalds { 377961a828dSTrond Myklebust struct rpc_xprt *xprt = data; 37849e9a890SChuck Lever 37949e9a890SChuck Lever xprt->snd_task = task; 380961a828dSTrond Myklebust return true; 381961a828dSTrond Myklebust } 382961a828dSTrond Myklebust 383961a828dSTrond Myklebust static void __xprt_lock_write_next(struct rpc_xprt *xprt) 384961a828dSTrond Myklebust { 385961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 38649e9a890SChuck Lever return; 387c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 388c544577dSTrond Myklebust goto out_unlock; 389f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 390f1dc237cSTrond Myklebust __xprt_lock_write_func, xprt)) 391961a828dSTrond Myklebust return; 392c544577dSTrond Myklebust out_unlock: 393632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 39449e9a890SChuck Lever } 39549e9a890SChuck Lever 396961a828dSTrond Myklebust static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) 397961a828dSTrond Myklebust { 398961a828dSTrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 399961a828dSTrond Myklebust return; 400c544577dSTrond Myklebust if (test_bit(XPRT_WRITE_SPACE, &xprt->state)) 401c544577dSTrond Myklebust goto out_unlock; 40275891f50STrond Myklebust if (xprt_need_congestion_window_wait(xprt)) 403961a828dSTrond Myklebust goto out_unlock; 404f1dc237cSTrond Myklebust if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, 40575891f50STrond Myklebust __xprt_lock_write_func, xprt)) 406961a828dSTrond Myklebust return; 4071da177e4SLinus Torvalds out_unlock: 408632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 4091da177e4SLinus Torvalds } 4101da177e4SLinus Torvalds 41149e9a890SChuck Lever /** 41249e9a890SChuck Lever * xprt_release_xprt - allow other requests to use a transport 41349e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 41449e9a890SChuck Lever * @task: task that is releasing access to the transport 41549e9a890SChuck Lever * 41649e9a890SChuck Lever * Note that "task" can be NULL. No congestion control is provided. 4171da177e4SLinus Torvalds */ 41849e9a890SChuck Lever void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) 4191da177e4SLinus Torvalds { 4201da177e4SLinus Torvalds if (xprt->snd_task == task) { 421632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 4221da177e4SLinus Torvalds __xprt_lock_write_next(xprt); 4231da177e4SLinus Torvalds } 424bf7ca707SChuck Lever trace_xprt_release_xprt(xprt, task); 4251da177e4SLinus Torvalds } 42612444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt); 4271da177e4SLinus Torvalds 42849e9a890SChuck Lever /** 42949e9a890SChuck Lever * xprt_release_xprt_cong - allow other requests to use a transport 43049e9a890SChuck Lever * @xprt: transport with other tasks potentially waiting 43149e9a890SChuck Lever * @task: task that is releasing access to the transport 43249e9a890SChuck Lever * 43349e9a890SChuck Lever * Note that "task" can be NULL. Another task is awoken to use the 43449e9a890SChuck Lever * transport if the transport's congestion window allows it. 43549e9a890SChuck Lever */ 43649e9a890SChuck Lever void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) 43749e9a890SChuck Lever { 43849e9a890SChuck Lever if (xprt->snd_task == task) { 439632e3bdcSTrond Myklebust xprt_clear_locked(xprt); 44049e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 44149e9a890SChuck Lever } 442bf7ca707SChuck Lever trace_xprt_release_cong(xprt, task); 44349e9a890SChuck Lever } 44412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); 44549e9a890SChuck Lever 446587bc725SOlga Kornievskaia void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) 4471da177e4SLinus Torvalds { 448bd79bc57STrond Myklebust if (xprt->snd_task != task) 449bd79bc57STrond Myklebust return; 450b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 45149e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 452b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 4531da177e4SLinus Torvalds } 4541da177e4SLinus Torvalds 4551da177e4SLinus Torvalds /* 4561da177e4SLinus Torvalds * Van Jacobson congestion avoidance. Check if the congestion window 4571da177e4SLinus Torvalds * overflowed. Put the task to sleep if this is the case. 4581da177e4SLinus Torvalds */ 4591da177e4SLinus Torvalds static int 46075891f50STrond Myklebust __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4611da177e4SLinus Torvalds { 4621da177e4SLinus Torvalds if (req->rq_cong) 4631da177e4SLinus Torvalds return 1; 464bf7ca707SChuck Lever trace_xprt_get_cong(xprt, req->rq_task); 46575891f50STrond Myklebust if (RPCXPRT_CONGESTED(xprt)) { 46675891f50STrond Myklebust xprt_set_congestion_window_wait(xprt); 4671da177e4SLinus Torvalds return 0; 46875891f50STrond Myklebust } 4691da177e4SLinus Torvalds req->rq_cong = 1; 4701da177e4SLinus Torvalds xprt->cong += RPC_CWNDSCALE; 4711da177e4SLinus Torvalds return 1; 4721da177e4SLinus Torvalds } 4731da177e4SLinus Torvalds 4741da177e4SLinus Torvalds /* 4751da177e4SLinus Torvalds * Adjust the congestion window, and wake up the next task 4761da177e4SLinus Torvalds * that has been sleeping due to congestion 4771da177e4SLinus Torvalds */ 4781da177e4SLinus Torvalds static void 4791da177e4SLinus Torvalds __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 4801da177e4SLinus Torvalds { 4811da177e4SLinus Torvalds if (!req->rq_cong) 4821da177e4SLinus Torvalds return; 4831da177e4SLinus Torvalds req->rq_cong = 0; 4841da177e4SLinus Torvalds xprt->cong -= RPC_CWNDSCALE; 48575891f50STrond Myklebust xprt_test_and_clear_congestion_window_wait(xprt); 486bf7ca707SChuck Lever trace_xprt_put_cong(xprt, req->rq_task); 48749e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 4881da177e4SLinus Torvalds } 4891da177e4SLinus Torvalds 49046c0ee8bSChuck Lever /** 49175891f50STrond Myklebust * xprt_request_get_cong - Request congestion control credits 49275891f50STrond Myklebust * @xprt: pointer to transport 49375891f50STrond Myklebust * @req: pointer to RPC request 49475891f50STrond Myklebust * 49575891f50STrond Myklebust * Useful for transports that require congestion control. 49675891f50STrond Myklebust */ 49775891f50STrond Myklebust bool 49875891f50STrond Myklebust xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) 49975891f50STrond Myklebust { 50075891f50STrond Myklebust bool ret = false; 50175891f50STrond Myklebust 50275891f50STrond Myklebust if (req->rq_cong) 50375891f50STrond Myklebust return true; 504b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 50575891f50STrond Myklebust ret = __xprt_get_cong(xprt, req) != 0; 506b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 50775891f50STrond Myklebust return ret; 50875891f50STrond Myklebust } 50975891f50STrond Myklebust EXPORT_SYMBOL_GPL(xprt_request_get_cong); 51075891f50STrond Myklebust 51175891f50STrond Myklebust /** 512a58dd398SChuck Lever * xprt_release_rqst_cong - housekeeping when request is complete 513a58dd398SChuck Lever * @task: RPC request that recently completed 514a58dd398SChuck Lever * 515a58dd398SChuck Lever * Useful for transports that require congestion control. 516a58dd398SChuck Lever */ 517a58dd398SChuck Lever void xprt_release_rqst_cong(struct rpc_task *task) 518a58dd398SChuck Lever { 519a4f0835cSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 520a4f0835cSTrond Myklebust 521a4f0835cSTrond Myklebust __xprt_put_cong(req->rq_xprt, req); 522a58dd398SChuck Lever } 52312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); 524a58dd398SChuck Lever 5258593e010SChuck Lever static void xprt_clear_congestion_window_wait_locked(struct rpc_xprt *xprt) 5268593e010SChuck Lever { 5278593e010SChuck Lever if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) 5288593e010SChuck Lever __xprt_lock_write_next_cong(xprt); 5298593e010SChuck Lever } 5308593e010SChuck Lever 53175891f50STrond Myklebust /* 53275891f50STrond Myklebust * Clear the congestion window wait flag and wake up the next 53375891f50STrond Myklebust * entry on xprt->sending 53475891f50STrond Myklebust */ 53575891f50STrond Myklebust static void 53675891f50STrond Myklebust xprt_clear_congestion_window_wait(struct rpc_xprt *xprt) 53775891f50STrond Myklebust { 53875891f50STrond Myklebust if (test_and_clear_bit(XPRT_CWND_WAIT, &xprt->state)) { 539b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 54075891f50STrond Myklebust __xprt_lock_write_next_cong(xprt); 541b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 54275891f50STrond Myklebust } 54375891f50STrond Myklebust } 54475891f50STrond Myklebust 545a58dd398SChuck Lever /** 54646c0ee8bSChuck Lever * xprt_adjust_cwnd - adjust transport congestion window 5476a24dfb6STrond Myklebust * @xprt: pointer to xprt 54846c0ee8bSChuck Lever * @task: recently completed RPC request used to adjust window 54946c0ee8bSChuck Lever * @result: result code of completed RPC request 55046c0ee8bSChuck Lever * 5514f4cf5adSChuck Lever * The transport code maintains an estimate on the maximum number of out- 5524f4cf5adSChuck Lever * standing RPC requests, using a smoothed version of the congestion 5534f4cf5adSChuck Lever * avoidance implemented in 44BSD. This is basically the Van Jacobson 5544f4cf5adSChuck Lever * congestion algorithm: If a retransmit occurs, the congestion window is 5554f4cf5adSChuck Lever * halved; otherwise, it is incremented by 1/cwnd when 5564f4cf5adSChuck Lever * 5574f4cf5adSChuck Lever * - a reply is received and 5584f4cf5adSChuck Lever * - a full number of requests are outstanding and 5594f4cf5adSChuck Lever * - the congestion window hasn't been updated recently. 5601da177e4SLinus Torvalds */ 5616a24dfb6STrond Myklebust void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) 5621da177e4SLinus Torvalds { 56346c0ee8bSChuck Lever struct rpc_rqst *req = task->tk_rqstp; 56446c0ee8bSChuck Lever unsigned long cwnd = xprt->cwnd; 5651da177e4SLinus Torvalds 5661da177e4SLinus Torvalds if (result >= 0 && cwnd <= xprt->cong) { 5671da177e4SLinus Torvalds /* The (cwnd >> 1) term makes sure 5681da177e4SLinus Torvalds * the result gets rounded properly. */ 5691da177e4SLinus Torvalds cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; 5701da177e4SLinus Torvalds if (cwnd > RPC_MAXCWND(xprt)) 5711da177e4SLinus Torvalds cwnd = RPC_MAXCWND(xprt); 57249e9a890SChuck Lever __xprt_lock_write_next_cong(xprt); 5731da177e4SLinus Torvalds } else if (result == -ETIMEDOUT) { 5741da177e4SLinus Torvalds cwnd >>= 1; 5751da177e4SLinus Torvalds if (cwnd < RPC_CWNDSCALE) 5761da177e4SLinus Torvalds cwnd = RPC_CWNDSCALE; 5771da177e4SLinus Torvalds } 5781da177e4SLinus Torvalds dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", 5791da177e4SLinus Torvalds xprt->cong, xprt->cwnd, cwnd); 5801da177e4SLinus Torvalds xprt->cwnd = cwnd; 58146c0ee8bSChuck Lever __xprt_put_cong(xprt, req); 5821da177e4SLinus Torvalds } 58312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); 5841da177e4SLinus Torvalds 58544fbac22SChuck Lever /** 58644fbac22SChuck Lever * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue 58744fbac22SChuck Lever * @xprt: transport with waiting tasks 58844fbac22SChuck Lever * @status: result code to plant in each task before waking it 58944fbac22SChuck Lever * 59044fbac22SChuck Lever */ 59144fbac22SChuck Lever void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) 59244fbac22SChuck Lever { 59344fbac22SChuck Lever if (status < 0) 59444fbac22SChuck Lever rpc_wake_up_status(&xprt->pending, status); 59544fbac22SChuck Lever else 59644fbac22SChuck Lever rpc_wake_up(&xprt->pending); 59744fbac22SChuck Lever } 59812444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); 59944fbac22SChuck Lever 600c7b2cae8SChuck Lever /** 601c7b2cae8SChuck Lever * xprt_wait_for_buffer_space - wait for transport output buffer to clear 602c544577dSTrond Myklebust * @xprt: transport 603a9a6b52eSTrond Myklebust * 604a9a6b52eSTrond Myklebust * Note that we only set the timer for the case of RPC_IS_SOFT(), since 605a9a6b52eSTrond Myklebust * we don't in general want to force a socket disconnection due to 606a9a6b52eSTrond Myklebust * an incomplete RPC call transmission. 607c7b2cae8SChuck Lever */ 608c544577dSTrond Myklebust void xprt_wait_for_buffer_space(struct rpc_xprt *xprt) 609c7b2cae8SChuck Lever { 610c544577dSTrond Myklebust set_bit(XPRT_WRITE_SPACE, &xprt->state); 611c7b2cae8SChuck Lever } 61212444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); 613c7b2cae8SChuck Lever 614c544577dSTrond Myklebust static bool 615c544577dSTrond Myklebust xprt_clear_write_space_locked(struct rpc_xprt *xprt) 616c544577dSTrond Myklebust { 617c544577dSTrond Myklebust if (test_and_clear_bit(XPRT_WRITE_SPACE, &xprt->state)) { 618c544577dSTrond Myklebust __xprt_lock_write_next(xprt); 619c544577dSTrond Myklebust dprintk("RPC: write space: waking waiting task on " 620c544577dSTrond Myklebust "xprt %p\n", xprt); 621c544577dSTrond Myklebust return true; 622c544577dSTrond Myklebust } 623c544577dSTrond Myklebust return false; 624c544577dSTrond Myklebust } 625c544577dSTrond Myklebust 626c7b2cae8SChuck Lever /** 627c7b2cae8SChuck Lever * xprt_write_space - wake the task waiting for transport output buffer space 628c7b2cae8SChuck Lever * @xprt: transport with waiting tasks 629c7b2cae8SChuck Lever * 630c7b2cae8SChuck Lever * Can be called in a soft IRQ context, so xprt_write_space never sleeps. 631c7b2cae8SChuck Lever */ 632c544577dSTrond Myklebust bool xprt_write_space(struct rpc_xprt *xprt) 633c7b2cae8SChuck Lever { 634c544577dSTrond Myklebust bool ret; 635c544577dSTrond Myklebust 636c544577dSTrond Myklebust if (!test_bit(XPRT_WRITE_SPACE, &xprt->state)) 637c544577dSTrond Myklebust return false; 638b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 639c544577dSTrond Myklebust ret = xprt_clear_write_space_locked(xprt); 640b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 641c544577dSTrond Myklebust return ret; 642c7b2cae8SChuck Lever } 64312444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_write_space); 644c7b2cae8SChuck Lever 645da953063STrond Myklebust static unsigned long xprt_abs_ktime_to_jiffies(ktime_t abstime) 646da953063STrond Myklebust { 647da953063STrond Myklebust s64 delta = ktime_to_ns(ktime_get() - abstime); 648da953063STrond Myklebust return likely(delta >= 0) ? 649da953063STrond Myklebust jiffies - nsecs_to_jiffies(delta) : 650da953063STrond Myklebust jiffies + nsecs_to_jiffies(-delta); 651da953063STrond Myklebust } 652da953063STrond Myklebust 653da953063STrond Myklebust static unsigned long xprt_calc_majortimeo(struct rpc_rqst *req) 6541da177e4SLinus Torvalds { 655ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 656da953063STrond Myklebust unsigned long majortimeo = req->rq_timeout; 6571da177e4SLinus Torvalds 6581da177e4SLinus Torvalds if (to->to_exponential) 659da953063STrond Myklebust majortimeo <<= to->to_retries; 6601da177e4SLinus Torvalds else 661da953063STrond Myklebust majortimeo += to->to_increment * to->to_retries; 662da953063STrond Myklebust if (majortimeo > to->to_maxval || majortimeo == 0) 663da953063STrond Myklebust majortimeo = to->to_maxval; 664da953063STrond Myklebust return majortimeo; 665da953063STrond Myklebust } 666da953063STrond Myklebust 667da953063STrond Myklebust static void xprt_reset_majortimeo(struct rpc_rqst *req) 668da953063STrond Myklebust { 669da953063STrond Myklebust req->rq_majortimeo += xprt_calc_majortimeo(req); 670da953063STrond Myklebust } 671da953063STrond Myklebust 6727de62bc0SOlga Kornievskaia static void xprt_reset_minortimeo(struct rpc_rqst *req) 6737de62bc0SOlga Kornievskaia { 6747de62bc0SOlga Kornievskaia req->rq_minortimeo += req->rq_timeout; 6757de62bc0SOlga Kornievskaia } 6767de62bc0SOlga Kornievskaia 677da953063STrond Myklebust static void xprt_init_majortimeo(struct rpc_task *task, struct rpc_rqst *req) 678da953063STrond Myklebust { 679da953063STrond Myklebust unsigned long time_init; 680da953063STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 681da953063STrond Myklebust 682da953063STrond Myklebust if (likely(xprt && xprt_connected(xprt))) 683da953063STrond Myklebust time_init = jiffies; 684da953063STrond Myklebust else 685da953063STrond Myklebust time_init = xprt_abs_ktime_to_jiffies(task->tk_start); 686da953063STrond Myklebust req->rq_timeout = task->tk_client->cl_timeout->to_initval; 687da953063STrond Myklebust req->rq_majortimeo = time_init + xprt_calc_majortimeo(req); 6887de62bc0SOlga Kornievskaia req->rq_minortimeo = time_init + req->rq_timeout; 6891da177e4SLinus Torvalds } 6901da177e4SLinus Torvalds 6919903cd1cSChuck Lever /** 6929903cd1cSChuck Lever * xprt_adjust_timeout - adjust timeout values for next retransmit 6939903cd1cSChuck Lever * @req: RPC request containing parameters to use for the adjustment 6949903cd1cSChuck Lever * 6951da177e4SLinus Torvalds */ 6961da177e4SLinus Torvalds int xprt_adjust_timeout(struct rpc_rqst *req) 6971da177e4SLinus Torvalds { 6981da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 699ba7392bbSTrond Myklebust const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; 7001da177e4SLinus Torvalds int status = 0; 7011da177e4SLinus Torvalds 70209252177SChris Dion if (time_before(jiffies, req->rq_majortimeo)) { 7037de62bc0SOlga Kornievskaia if (time_before(jiffies, req->rq_minortimeo)) 7047de62bc0SOlga Kornievskaia return status; 7051da177e4SLinus Torvalds if (to->to_exponential) 7061da177e4SLinus Torvalds req->rq_timeout <<= 1; 7071da177e4SLinus Torvalds else 7081da177e4SLinus Torvalds req->rq_timeout += to->to_increment; 7091da177e4SLinus Torvalds if (to->to_maxval && req->rq_timeout >= to->to_maxval) 7101da177e4SLinus Torvalds req->rq_timeout = to->to_maxval; 7111da177e4SLinus Torvalds req->rq_retries++; 7121da177e4SLinus Torvalds } else { 7131da177e4SLinus Torvalds req->rq_timeout = to->to_initval; 7141da177e4SLinus Torvalds req->rq_retries = 0; 7151da177e4SLinus Torvalds xprt_reset_majortimeo(req); 7161da177e4SLinus Torvalds /* Reset the RTT counters == "slow start" */ 717b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 7181da177e4SLinus Torvalds rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); 719b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 7201da177e4SLinus Torvalds status = -ETIMEDOUT; 7211da177e4SLinus Torvalds } 7227de62bc0SOlga Kornievskaia xprt_reset_minortimeo(req); 7231da177e4SLinus Torvalds 7241da177e4SLinus Torvalds if (req->rq_timeout == 0) { 7251da177e4SLinus Torvalds printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); 7261da177e4SLinus Torvalds req->rq_timeout = 5 * HZ; 7271da177e4SLinus Torvalds } 7281da177e4SLinus Torvalds return status; 7291da177e4SLinus Torvalds } 7301da177e4SLinus Torvalds 73165f27f38SDavid Howells static void xprt_autoclose(struct work_struct *work) 7321da177e4SLinus Torvalds { 73365f27f38SDavid Howells struct rpc_xprt *xprt = 73465f27f38SDavid Howells container_of(work, struct rpc_xprt, task_cleanup); 735a1231fdaSTrond Myklebust unsigned int pflags = memalloc_nofs_save(); 7361da177e4SLinus Torvalds 737911813d7SChuck Lever trace_xprt_disconnect_auto(xprt); 738d896ba83STrond Myklebust xprt->connect_cookie++; 739d896ba83STrond Myklebust smp_mb__before_atomic(); 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 /** 765e26d9972STrond Myklebust * xprt_schedule_autoclose_locked - Try to schedule an autoclose RPC call 766e26d9972STrond Myklebust * @xprt: transport to disconnect 767e26d9972STrond Myklebust */ 768e26d9972STrond Myklebust static void xprt_schedule_autoclose_locked(struct rpc_xprt *xprt) 769e26d9972STrond Myklebust { 770*3be232f1STrond Myklebust if (test_and_set_bit(XPRT_CLOSE_WAIT, &xprt->state)) 771*3be232f1STrond Myklebust return; 772e26d9972STrond Myklebust if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) 773e26d9972STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 774e26d9972STrond Myklebust else if (xprt->snd_task && !test_bit(XPRT_SND_IS_COOKIE, &xprt->state)) 775e26d9972STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 776e26d9972STrond Myklebust xprt->snd_task, -ENOTCONN); 777e26d9972STrond Myklebust } 778e26d9972STrond Myklebust 779e26d9972STrond Myklebust /** 78066af1e55STrond Myklebust * xprt_force_disconnect - force a transport to disconnect 78166af1e55STrond Myklebust * @xprt: transport to disconnect 78266af1e55STrond Myklebust * 78366af1e55STrond Myklebust */ 78466af1e55STrond Myklebust void xprt_force_disconnect(struct rpc_xprt *xprt) 78566af1e55STrond Myklebust { 786911813d7SChuck Lever trace_xprt_disconnect_force(xprt); 787911813d7SChuck Lever 78866af1e55STrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 789b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 790e26d9972STrond Myklebust xprt_schedule_autoclose_locked(xprt); 791b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 79266af1e55STrond Myklebust } 793e2a4f4fbSChuck Lever EXPORT_SYMBOL_GPL(xprt_force_disconnect); 79466af1e55STrond Myklebust 7957f3a1d1eSTrond Myklebust static unsigned int 7967f3a1d1eSTrond Myklebust xprt_connect_cookie(struct rpc_xprt *xprt) 7977f3a1d1eSTrond Myklebust { 7987f3a1d1eSTrond Myklebust return READ_ONCE(xprt->connect_cookie); 7997f3a1d1eSTrond Myklebust } 8007f3a1d1eSTrond Myklebust 8017f3a1d1eSTrond Myklebust static bool 8027f3a1d1eSTrond Myklebust xprt_request_retransmit_after_disconnect(struct rpc_task *task) 8037f3a1d1eSTrond Myklebust { 8047f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 8057f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 8067f3a1d1eSTrond Myklebust 8077f3a1d1eSTrond Myklebust return req->rq_connect_cookie != xprt_connect_cookie(xprt) || 8087f3a1d1eSTrond Myklebust !xprt_connected(xprt); 8097f3a1d1eSTrond Myklebust } 8107f3a1d1eSTrond Myklebust 8117c1d71cfSTrond Myklebust /** 8127c1d71cfSTrond Myklebust * xprt_conditional_disconnect - force a transport to disconnect 8137c1d71cfSTrond Myklebust * @xprt: transport to disconnect 8147c1d71cfSTrond Myklebust * @cookie: 'connection cookie' 8157c1d71cfSTrond Myklebust * 8167c1d71cfSTrond Myklebust * This attempts to break the connection if and only if 'cookie' matches 8177c1d71cfSTrond Myklebust * the current transport 'connection cookie'. It ensures that we don't 8187c1d71cfSTrond Myklebust * try to break the connection more than once when we need to retransmit 8197c1d71cfSTrond Myklebust * a batch of RPC requests. 8207c1d71cfSTrond Myklebust * 8217c1d71cfSTrond Myklebust */ 8227c1d71cfSTrond Myklebust void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) 8237c1d71cfSTrond Myklebust { 8247c1d71cfSTrond Myklebust /* Don't race with the test_bit() in xprt_clear_locked() */ 825b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 8267c1d71cfSTrond Myklebust if (cookie != xprt->connect_cookie) 8277c1d71cfSTrond Myklebust goto out; 8282c2ee6d2SNeilBrown if (test_bit(XPRT_CLOSING, &xprt->state)) 8297c1d71cfSTrond Myklebust goto out; 830e26d9972STrond Myklebust xprt_schedule_autoclose_locked(xprt); 8317c1d71cfSTrond Myklebust out: 832b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 8337c1d71cfSTrond Myklebust } 8347c1d71cfSTrond Myklebust 835ad3331acSTrond Myklebust static bool 836ad3331acSTrond Myklebust xprt_has_timer(const struct rpc_xprt *xprt) 837ad3331acSTrond Myklebust { 838ad3331acSTrond Myklebust return xprt->idle_timeout != 0; 839ad3331acSTrond Myklebust } 840ad3331acSTrond Myklebust 841ad3331acSTrond Myklebust static void 842ad3331acSTrond Myklebust xprt_schedule_autodisconnect(struct rpc_xprt *xprt) 843ad3331acSTrond Myklebust __must_hold(&xprt->transport_lock) 844ad3331acSTrond Myklebust { 84580d3c45fSDave Wysochanski xprt->last_used = jiffies; 84695f7691dSTrond Myklebust if (RB_EMPTY_ROOT(&xprt->recv_queue) && xprt_has_timer(xprt)) 847ad3331acSTrond Myklebust mod_timer(&xprt->timer, xprt->last_used + xprt->idle_timeout); 848ad3331acSTrond Myklebust } 849ad3331acSTrond Myklebust 8501da177e4SLinus Torvalds static void 851ff861c4dSKees Cook xprt_init_autodisconnect(struct timer_list *t) 8521da177e4SLinus Torvalds { 853ff861c4dSKees Cook struct rpc_xprt *xprt = from_timer(xprt, t, timer); 8541da177e4SLinus Torvalds 85595f7691dSTrond Myklebust if (!RB_EMPTY_ROOT(&xprt->recv_queue)) 856b5e92419STrond Myklebust return; 857ad3331acSTrond Myklebust /* Reset xprt->last_used to avoid connect/autodisconnect cycling */ 858ad3331acSTrond Myklebust xprt->last_used = jiffies; 8592226feb6SChuck Lever if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) 8601da177e4SLinus Torvalds return; 861b5e92419STrond Myklebust queue_work(xprtiod_workqueue, &xprt->task_cleanup); 8621da177e4SLinus Torvalds } 8631da177e4SLinus Torvalds 864a4ae3081SChuck Lever #if IS_ENABLED(CONFIG_FAIL_SUNRPC) 865a4ae3081SChuck Lever static void xprt_inject_disconnect(struct rpc_xprt *xprt) 866a4ae3081SChuck Lever { 867a4ae3081SChuck Lever if (!fail_sunrpc.ignore_client_disconnect && 868a4ae3081SChuck Lever should_fail(&fail_sunrpc.attr, 1)) 869a4ae3081SChuck Lever xprt->ops->inject_disconnect(xprt); 870a4ae3081SChuck Lever } 871a4ae3081SChuck Lever #else 872a4ae3081SChuck Lever static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 873a4ae3081SChuck Lever { 874a4ae3081SChuck Lever } 875a4ae3081SChuck Lever #endif 876a4ae3081SChuck Lever 877718ba5b8STrond Myklebust bool xprt_lock_connect(struct rpc_xprt *xprt, 878718ba5b8STrond Myklebust struct rpc_task *task, 879718ba5b8STrond Myklebust void *cookie) 880718ba5b8STrond Myklebust { 881718ba5b8STrond Myklebust bool ret = false; 882718ba5b8STrond Myklebust 883b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 884718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 885718ba5b8STrond Myklebust goto out; 886718ba5b8STrond Myklebust if (xprt->snd_task != task) 887718ba5b8STrond Myklebust goto out; 888c2dc3e5fSTrond Myklebust set_bit(XPRT_SND_IS_COOKIE, &xprt->state); 889718ba5b8STrond Myklebust xprt->snd_task = cookie; 890718ba5b8STrond Myklebust ret = true; 891718ba5b8STrond Myklebust out: 892b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 893718ba5b8STrond Myklebust return ret; 894718ba5b8STrond Myklebust } 895f99fa508STrond Myklebust EXPORT_SYMBOL_GPL(xprt_lock_connect); 896718ba5b8STrond Myklebust 897718ba5b8STrond Myklebust void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) 898718ba5b8STrond Myklebust { 899b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 900718ba5b8STrond Myklebust if (xprt->snd_task != cookie) 901718ba5b8STrond Myklebust goto out; 902718ba5b8STrond Myklebust if (!test_bit(XPRT_LOCKED, &xprt->state)) 903718ba5b8STrond Myklebust goto out; 904718ba5b8STrond Myklebust xprt->snd_task =NULL; 905c2dc3e5fSTrond Myklebust clear_bit(XPRT_SND_IS_COOKIE, &xprt->state); 906718ba5b8STrond Myklebust xprt->ops->release_xprt(xprt, NULL); 907ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 908718ba5b8STrond Myklebust out: 909b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 91079234c3dSTrond Myklebust wake_up_bit(&xprt->state, XPRT_LOCKED); 911718ba5b8STrond Myklebust } 912f99fa508STrond Myklebust EXPORT_SYMBOL_GPL(xprt_unlock_connect); 913718ba5b8STrond Myklebust 9149903cd1cSChuck Lever /** 9159903cd1cSChuck Lever * xprt_connect - schedule a transport connect operation 9169903cd1cSChuck Lever * @task: RPC task that is requesting the connect 9171da177e4SLinus Torvalds * 9181da177e4SLinus Torvalds */ 9191da177e4SLinus Torvalds void xprt_connect(struct rpc_task *task) 9201da177e4SLinus Torvalds { 921ad2368d6STrond Myklebust struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 9221da177e4SLinus Torvalds 923db0a86c4SChuck Lever trace_xprt_connect(xprt); 9241da177e4SLinus Torvalds 925ec739ef0SChuck Lever if (!xprt_bound(xprt)) { 92601d37c42STrond Myklebust task->tk_status = -EAGAIN; 9271da177e4SLinus Torvalds return; 9281da177e4SLinus Torvalds } 9291da177e4SLinus Torvalds if (!xprt_lock_write(xprt, task)) 9301da177e4SLinus Torvalds return; 931feb8ca37STrond Myklebust 932911813d7SChuck Lever if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) { 933911813d7SChuck Lever trace_xprt_disconnect_cleanup(xprt); 934feb8ca37STrond Myklebust xprt->ops->close(xprt); 935911813d7SChuck Lever } 936feb8ca37STrond Myklebust 937718ba5b8STrond Myklebust if (!xprt_connected(xprt)) { 9382c2ee6d2SNeilBrown task->tk_rqstp->rq_connect_cookie = xprt->connect_cookie; 9396b2e6856STrond Myklebust rpc_sleep_on_timeout(&xprt->pending, task, NULL, 9409e910bffSTrond Myklebust xprt_request_timeout(task->tk_rqstp)); 9410b9e7943STrond Myklebust 9420b9e7943STrond Myklebust if (test_bit(XPRT_CLOSING, &xprt->state)) 9430b9e7943STrond Myklebust return; 9440b9e7943STrond Myklebust if (xprt_test_and_set_connecting(xprt)) 9450b9e7943STrond Myklebust return; 9460a9a4304STrond Myklebust /* Race breaker */ 9470a9a4304STrond Myklebust if (!xprt_connected(xprt)) { 948262ca07dSChuck Lever xprt->stat.connect_start = jiffies; 9491b092092STrond Myklebust xprt->ops->connect(xprt, task); 9500a9a4304STrond Myklebust } else { 9510a9a4304STrond Myklebust xprt_clear_connecting(xprt); 9520a9a4304STrond Myklebust task->tk_status = 0; 9530a9a4304STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 9540a9a4304STrond Myklebust } 9551da177e4SLinus Torvalds } 956718ba5b8STrond Myklebust xprt_release_write(xprt, task); 9571da177e4SLinus Torvalds } 9581da177e4SLinus Torvalds 959675dd90aSChuck Lever /** 960675dd90aSChuck Lever * xprt_reconnect_delay - compute the wait before scheduling a connect 961675dd90aSChuck Lever * @xprt: transport instance 962675dd90aSChuck Lever * 963675dd90aSChuck Lever */ 964675dd90aSChuck Lever unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt) 965675dd90aSChuck Lever { 966675dd90aSChuck Lever unsigned long start, now = jiffies; 967675dd90aSChuck Lever 968675dd90aSChuck Lever start = xprt->stat.connect_start + xprt->reestablish_timeout; 969675dd90aSChuck Lever if (time_after(start, now)) 970675dd90aSChuck Lever return start - now; 971675dd90aSChuck Lever return 0; 972675dd90aSChuck Lever } 973675dd90aSChuck Lever EXPORT_SYMBOL_GPL(xprt_reconnect_delay); 974675dd90aSChuck Lever 975675dd90aSChuck Lever /** 976675dd90aSChuck Lever * xprt_reconnect_backoff - compute the new re-establish timeout 977675dd90aSChuck Lever * @xprt: transport instance 978675dd90aSChuck Lever * @init_to: initial reestablish timeout 979675dd90aSChuck Lever * 980675dd90aSChuck Lever */ 981675dd90aSChuck Lever void xprt_reconnect_backoff(struct rpc_xprt *xprt, unsigned long init_to) 982675dd90aSChuck Lever { 983675dd90aSChuck Lever xprt->reestablish_timeout <<= 1; 984675dd90aSChuck Lever if (xprt->reestablish_timeout > xprt->max_reconnect_timeout) 985675dd90aSChuck Lever xprt->reestablish_timeout = xprt->max_reconnect_timeout; 986675dd90aSChuck Lever if (xprt->reestablish_timeout < init_to) 987675dd90aSChuck Lever xprt->reestablish_timeout = init_to; 988675dd90aSChuck Lever } 989675dd90aSChuck Lever EXPORT_SYMBOL_GPL(xprt_reconnect_backoff); 990675dd90aSChuck Lever 99195f7691dSTrond Myklebust enum xprt_xid_rb_cmp { 99295f7691dSTrond Myklebust XID_RB_EQUAL, 99395f7691dSTrond Myklebust XID_RB_LEFT, 99495f7691dSTrond Myklebust XID_RB_RIGHT, 99595f7691dSTrond Myklebust }; 99695f7691dSTrond Myklebust static enum xprt_xid_rb_cmp 99795f7691dSTrond Myklebust xprt_xid_cmp(__be32 xid1, __be32 xid2) 99895f7691dSTrond Myklebust { 99995f7691dSTrond Myklebust if (xid1 == xid2) 100095f7691dSTrond Myklebust return XID_RB_EQUAL; 100195f7691dSTrond Myklebust if ((__force u32)xid1 < (__force u32)xid2) 100295f7691dSTrond Myklebust return XID_RB_LEFT; 100395f7691dSTrond Myklebust return XID_RB_RIGHT; 100495f7691dSTrond Myklebust } 100595f7691dSTrond Myklebust 100695f7691dSTrond Myklebust static struct rpc_rqst * 100795f7691dSTrond Myklebust xprt_request_rb_find(struct rpc_xprt *xprt, __be32 xid) 100895f7691dSTrond Myklebust { 100995f7691dSTrond Myklebust struct rb_node *n = xprt->recv_queue.rb_node; 101095f7691dSTrond Myklebust struct rpc_rqst *req; 101195f7691dSTrond Myklebust 101295f7691dSTrond Myklebust while (n != NULL) { 101395f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 101495f7691dSTrond Myklebust switch (xprt_xid_cmp(xid, req->rq_xid)) { 101595f7691dSTrond Myklebust case XID_RB_LEFT: 101695f7691dSTrond Myklebust n = n->rb_left; 101795f7691dSTrond Myklebust break; 101895f7691dSTrond Myklebust case XID_RB_RIGHT: 101995f7691dSTrond Myklebust n = n->rb_right; 102095f7691dSTrond Myklebust break; 102195f7691dSTrond Myklebust case XID_RB_EQUAL: 102295f7691dSTrond Myklebust return req; 102395f7691dSTrond Myklebust } 102495f7691dSTrond Myklebust } 102595f7691dSTrond Myklebust return NULL; 102695f7691dSTrond Myklebust } 102795f7691dSTrond Myklebust 102895f7691dSTrond Myklebust static void 102995f7691dSTrond Myklebust xprt_request_rb_insert(struct rpc_xprt *xprt, struct rpc_rqst *new) 103095f7691dSTrond Myklebust { 103195f7691dSTrond Myklebust struct rb_node **p = &xprt->recv_queue.rb_node; 103295f7691dSTrond Myklebust struct rb_node *n = NULL; 103395f7691dSTrond Myklebust struct rpc_rqst *req; 103495f7691dSTrond Myklebust 103595f7691dSTrond Myklebust while (*p != NULL) { 103695f7691dSTrond Myklebust n = *p; 103795f7691dSTrond Myklebust req = rb_entry(n, struct rpc_rqst, rq_recv); 103895f7691dSTrond Myklebust switch(xprt_xid_cmp(new->rq_xid, req->rq_xid)) { 103995f7691dSTrond Myklebust case XID_RB_LEFT: 104095f7691dSTrond Myklebust p = &n->rb_left; 104195f7691dSTrond Myklebust break; 104295f7691dSTrond Myklebust case XID_RB_RIGHT: 104395f7691dSTrond Myklebust p = &n->rb_right; 104495f7691dSTrond Myklebust break; 104595f7691dSTrond Myklebust case XID_RB_EQUAL: 104695f7691dSTrond Myklebust WARN_ON_ONCE(new != req); 104795f7691dSTrond Myklebust return; 104895f7691dSTrond Myklebust } 104995f7691dSTrond Myklebust } 105095f7691dSTrond Myklebust rb_link_node(&new->rq_recv, n, p); 105195f7691dSTrond Myklebust rb_insert_color(&new->rq_recv, &xprt->recv_queue); 105295f7691dSTrond Myklebust } 105395f7691dSTrond Myklebust 105495f7691dSTrond Myklebust static void 105595f7691dSTrond Myklebust xprt_request_rb_remove(struct rpc_xprt *xprt, struct rpc_rqst *req) 105695f7691dSTrond Myklebust { 105795f7691dSTrond Myklebust rb_erase(&req->rq_recv, &xprt->recv_queue); 105895f7691dSTrond Myklebust } 105995f7691dSTrond Myklebust 10609903cd1cSChuck Lever /** 10619903cd1cSChuck Lever * xprt_lookup_rqst - find an RPC request corresponding to an XID 10629903cd1cSChuck Lever * @xprt: transport on which the original request was transmitted 10639903cd1cSChuck Lever * @xid: RPC XID of incoming reply 10649903cd1cSChuck Lever * 106575c84151STrond Myklebust * Caller holds xprt->queue_lock. 10661da177e4SLinus Torvalds */ 1067d8ed029dSAlexey Dobriyan struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) 10681da177e4SLinus Torvalds { 10698f3a6de3SPavel Emelyanov struct rpc_rqst *entry; 10701da177e4SLinus Torvalds 107195f7691dSTrond Myklebust entry = xprt_request_rb_find(xprt, xid); 107295f7691dSTrond Myklebust if (entry != NULL) { 10733705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, 0); 10740b87a46bSChuck Lever entry->rq_rtt = ktime_sub(ktime_get(), entry->rq_xtime); 1075262ca07dSChuck Lever return entry; 10763705ad64SJeff Layton } 107746121cf7SChuck Lever 107846121cf7SChuck Lever dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", 107946121cf7SChuck Lever ntohl(xid)); 10803705ad64SJeff Layton trace_xprt_lookup_rqst(xprt, xid, -ENOENT); 1081262ca07dSChuck Lever xprt->stat.bad_xids++; 1082262ca07dSChuck Lever return NULL; 10831da177e4SLinus Torvalds } 108412444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_lookup_rqst); 10851da177e4SLinus Torvalds 1086cf9946cdSTrond Myklebust static bool 1087cf9946cdSTrond Myklebust xprt_is_pinned_rqst(struct rpc_rqst *req) 1088cf9946cdSTrond Myklebust { 1089cf9946cdSTrond Myklebust return atomic_read(&req->rq_pin) != 0; 1090cf9946cdSTrond Myklebust } 1091cf9946cdSTrond Myklebust 1092729749bbSTrond Myklebust /** 1093729749bbSTrond Myklebust * xprt_pin_rqst - Pin a request on the transport receive list 1094729749bbSTrond Myklebust * @req: Request to pin 1095729749bbSTrond Myklebust * 1096729749bbSTrond Myklebust * Caller must ensure this is atomic with the call to xprt_lookup_rqst() 10971f7d1c73SChuck Lever * so should be holding xprt->queue_lock. 1098729749bbSTrond Myklebust */ 1099729749bbSTrond Myklebust void xprt_pin_rqst(struct rpc_rqst *req) 1100729749bbSTrond Myklebust { 1101cf9946cdSTrond Myklebust atomic_inc(&req->rq_pin); 1102729749bbSTrond Myklebust } 11039590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_pin_rqst); 1104729749bbSTrond Myklebust 1105729749bbSTrond Myklebust /** 1106729749bbSTrond Myklebust * xprt_unpin_rqst - Unpin a request on the transport receive list 1107729749bbSTrond Myklebust * @req: Request to pin 1108729749bbSTrond Myklebust * 11091f7d1c73SChuck Lever * Caller should be holding xprt->queue_lock. 1110729749bbSTrond Myklebust */ 1111729749bbSTrond Myklebust void xprt_unpin_rqst(struct rpc_rqst *req) 1112729749bbSTrond Myklebust { 1113cf9946cdSTrond Myklebust if (!test_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate)) { 1114cf9946cdSTrond Myklebust atomic_dec(&req->rq_pin); 1115cf9946cdSTrond Myklebust return; 1116cf9946cdSTrond Myklebust } 1117cf9946cdSTrond Myklebust if (atomic_dec_and_test(&req->rq_pin)) 1118cf9946cdSTrond Myklebust wake_up_var(&req->rq_pin); 1119729749bbSTrond Myklebust } 11209590d083SChuck Lever EXPORT_SYMBOL_GPL(xprt_unpin_rqst); 1121729749bbSTrond Myklebust 1122729749bbSTrond Myklebust static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) 1123729749bbSTrond Myklebust { 1124cf9946cdSTrond Myklebust wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); 1125729749bbSTrond Myklebust } 1126729749bbSTrond Myklebust 1127edc81dcdSTrond Myklebust static bool 1128edc81dcdSTrond Myklebust xprt_request_data_received(struct rpc_task *task) 1129edc81dcdSTrond Myklebust { 1130edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 1131edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; 1132edc81dcdSTrond Myklebust } 1133edc81dcdSTrond Myklebust 1134edc81dcdSTrond Myklebust static bool 1135edc81dcdSTrond Myklebust xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst *req) 1136edc81dcdSTrond Myklebust { 1137edc81dcdSTrond Myklebust return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && 1138edc81dcdSTrond Myklebust READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) == 0; 1139edc81dcdSTrond Myklebust } 1140edc81dcdSTrond Myklebust 1141edc81dcdSTrond Myklebust /** 1142edc81dcdSTrond Myklebust * xprt_request_enqueue_receive - Add an request to the receive queue 1143edc81dcdSTrond Myklebust * @task: RPC task 1144edc81dcdSTrond Myklebust * 1145edc81dcdSTrond Myklebust */ 1146edc81dcdSTrond Myklebust void 1147edc81dcdSTrond Myklebust xprt_request_enqueue_receive(struct rpc_task *task) 1148edc81dcdSTrond Myklebust { 1149edc81dcdSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1150edc81dcdSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1151edc81dcdSTrond Myklebust 1152edc81dcdSTrond Myklebust if (!xprt_request_need_enqueue_receive(task, req)) 1153edc81dcdSTrond Myklebust return; 115475369089STrond Myklebust 115575369089STrond Myklebust xprt_request_prepare(task->tk_rqstp); 1156edc81dcdSTrond Myklebust spin_lock(&xprt->queue_lock); 1157edc81dcdSTrond Myklebust 1158edc81dcdSTrond Myklebust /* Update the softirq receive buffer */ 1159edc81dcdSTrond Myklebust memcpy(&req->rq_private_buf, &req->rq_rcv_buf, 1160edc81dcdSTrond Myklebust sizeof(req->rq_private_buf)); 1161edc81dcdSTrond Myklebust 1162edc81dcdSTrond Myklebust /* Add request to the receive list */ 116395f7691dSTrond Myklebust xprt_request_rb_insert(xprt, req); 1164edc81dcdSTrond Myklebust set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); 1165edc81dcdSTrond Myklebust spin_unlock(&xprt->queue_lock); 1166edc81dcdSTrond Myklebust 1167edc81dcdSTrond Myklebust /* Turn off autodisconnect */ 1168edc81dcdSTrond Myklebust del_singleshot_timer_sync(&xprt->timer); 1169edc81dcdSTrond Myklebust } 1170edc81dcdSTrond Myklebust 1171edc81dcdSTrond Myklebust /** 1172edc81dcdSTrond Myklebust * xprt_request_dequeue_receive_locked - Remove a request from the receive queue 1173edc81dcdSTrond Myklebust * @task: RPC task 1174edc81dcdSTrond Myklebust * 1175edc81dcdSTrond Myklebust * Caller must hold xprt->queue_lock. 1176edc81dcdSTrond Myklebust */ 1177edc81dcdSTrond Myklebust static void 1178edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(struct rpc_task *task) 1179edc81dcdSTrond Myklebust { 118095f7691dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 118195f7691dSTrond Myklebust 1182edc81dcdSTrond Myklebust if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 118395f7691dSTrond Myklebust xprt_request_rb_remove(req->rq_xprt, req); 1184edc81dcdSTrond Myklebust } 1185edc81dcdSTrond Myklebust 1186ecd465eeSChuck Lever /** 1187ecd465eeSChuck Lever * xprt_update_rtt - Update RPC RTT statistics 1188ecd465eeSChuck Lever * @task: RPC request that recently completed 1189ecd465eeSChuck Lever * 119075c84151STrond Myklebust * Caller holds xprt->queue_lock. 1191ecd465eeSChuck Lever */ 1192ecd465eeSChuck Lever void xprt_update_rtt(struct rpc_task *task) 11931da177e4SLinus Torvalds { 11941570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 11951570c1e4SChuck Lever struct rpc_rtt *rtt = task->tk_client->cl_rtt; 119695c96174SEric Dumazet unsigned int timer = task->tk_msg.rpc_proc->p_timer; 1197d60dbb20STrond Myklebust long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); 11981570c1e4SChuck Lever 11991da177e4SLinus Torvalds if (timer) { 12001da177e4SLinus Torvalds if (req->rq_ntrans == 1) 1201ff839970SChuck Lever rpc_update_rtt(rtt, timer, m); 12021570c1e4SChuck Lever rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); 12031da177e4SLinus Torvalds } 12041da177e4SLinus Torvalds } 1205ecd465eeSChuck Lever EXPORT_SYMBOL_GPL(xprt_update_rtt); 12061da177e4SLinus Torvalds 12071570c1e4SChuck Lever /** 12081570c1e4SChuck Lever * xprt_complete_rqst - called when reply processing is complete 12091570c1e4SChuck Lever * @task: RPC request that recently completed 12101570c1e4SChuck Lever * @copied: actual number of bytes received from the transport 12111570c1e4SChuck Lever * 121275c84151STrond Myklebust * Caller holds xprt->queue_lock. 12131570c1e4SChuck Lever */ 12141570c1e4SChuck Lever void xprt_complete_rqst(struct rpc_task *task, int copied) 12151570c1e4SChuck Lever { 12161570c1e4SChuck Lever struct rpc_rqst *req = task->tk_rqstp; 1217fda13939STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12181da177e4SLinus Torvalds 1219fda13939STrond Myklebust xprt->stat.recvs++; 1220ef759a2eSChuck Lever 12211e799b67STrond Myklebust req->rq_private_buf.len = copied; 1222dd2b63d0SRicardo Labiaga /* Ensure all writes are done before we update */ 1223dd2b63d0SRicardo Labiaga /* req->rq_reply_bytes_recvd */ 122443ac3f29STrond Myklebust smp_wmb(); 1225dd2b63d0SRicardo Labiaga req->rq_reply_bytes_recvd = copied; 1226edc81dcdSTrond Myklebust xprt_request_dequeue_receive_locked(task); 1227fda13939STrond Myklebust rpc_wake_up_queued_task(&xprt->pending, task); 12281da177e4SLinus Torvalds } 122912444809S\"Talpey, Thomas\ EXPORT_SYMBOL_GPL(xprt_complete_rqst); 12301da177e4SLinus Torvalds 123146c0ee8bSChuck Lever static void xprt_timer(struct rpc_task *task) 12321da177e4SLinus Torvalds { 12331da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 12341da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 12351da177e4SLinus Torvalds 12365d00837bSTrond Myklebust if (task->tk_status != -ETIMEDOUT) 12375d00837bSTrond Myklebust return; 123846c0ee8bSChuck Lever 123982476d9fSChuck Lever trace_xprt_timer(xprt, req->rq_xid, task->tk_status); 1240dd2b63d0SRicardo Labiaga if (!req->rq_reply_bytes_recvd) { 124146c0ee8bSChuck Lever if (xprt->ops->timer) 12426a24dfb6STrond Myklebust xprt->ops->timer(xprt, task); 12435d00837bSTrond Myklebust } else 12445d00837bSTrond Myklebust task->tk_status = 0; 12451da177e4SLinus Torvalds } 12461da177e4SLinus Torvalds 12479903cd1cSChuck Lever /** 12488ba6a92dSTrond Myklebust * xprt_wait_for_reply_request_def - wait for reply 12498ba6a92dSTrond Myklebust * @task: pointer to rpc_task 12508ba6a92dSTrond Myklebust * 12518ba6a92dSTrond Myklebust * Set a request's retransmit timeout based on the transport's 12528ba6a92dSTrond Myklebust * default timeout parameters. Used by transports that don't adjust 12538ba6a92dSTrond Myklebust * the retransmit timeout based on round-trip time estimation, 12548ba6a92dSTrond Myklebust * and put the task to sleep on the pending queue. 12558ba6a92dSTrond Myklebust */ 12568ba6a92dSTrond Myklebust void xprt_wait_for_reply_request_def(struct rpc_task *task) 12578ba6a92dSTrond Myklebust { 12588ba6a92dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12598ba6a92dSTrond Myklebust 12606b2e6856STrond Myklebust rpc_sleep_on_timeout(&req->rq_xprt->pending, task, xprt_timer, 12619e910bffSTrond Myklebust xprt_request_timeout(req)); 12628ba6a92dSTrond Myklebust } 12638ba6a92dSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_wait_for_reply_request_def); 12648ba6a92dSTrond Myklebust 12658ba6a92dSTrond Myklebust /** 12668ba6a92dSTrond Myklebust * xprt_wait_for_reply_request_rtt - wait for reply using RTT estimator 12678ba6a92dSTrond Myklebust * @task: pointer to rpc_task 12688ba6a92dSTrond Myklebust * 12698ba6a92dSTrond Myklebust * Set a request's retransmit timeout using the RTT estimator, 12708ba6a92dSTrond Myklebust * and put the task to sleep on the pending queue. 12718ba6a92dSTrond Myklebust */ 12728ba6a92dSTrond Myklebust void xprt_wait_for_reply_request_rtt(struct rpc_task *task) 12738ba6a92dSTrond Myklebust { 12748ba6a92dSTrond Myklebust int timer = task->tk_msg.rpc_proc->p_timer; 12758ba6a92dSTrond Myklebust struct rpc_clnt *clnt = task->tk_client; 12768ba6a92dSTrond Myklebust struct rpc_rtt *rtt = clnt->cl_rtt; 12778ba6a92dSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12788ba6a92dSTrond Myklebust unsigned long max_timeout = clnt->cl_timeout->to_maxval; 12796b2e6856STrond Myklebust unsigned long timeout; 12808ba6a92dSTrond Myklebust 12816b2e6856STrond Myklebust timeout = rpc_calc_rto(rtt, timer); 12826b2e6856STrond Myklebust timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; 12836b2e6856STrond Myklebust if (timeout > max_timeout || timeout == 0) 12846b2e6856STrond Myklebust timeout = max_timeout; 12856b2e6856STrond Myklebust rpc_sleep_on_timeout(&req->rq_xprt->pending, task, xprt_timer, 12866b2e6856STrond Myklebust jiffies + timeout); 12878ba6a92dSTrond Myklebust } 12888ba6a92dSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_wait_for_reply_request_rtt); 12898ba6a92dSTrond Myklebust 12908ba6a92dSTrond Myklebust /** 12917f3a1d1eSTrond Myklebust * xprt_request_wait_receive - wait for the reply to an RPC request 12927f3a1d1eSTrond Myklebust * @task: RPC task about to send a request 12937f3a1d1eSTrond Myklebust * 12947f3a1d1eSTrond Myklebust */ 12957f3a1d1eSTrond Myklebust void xprt_request_wait_receive(struct rpc_task *task) 12967f3a1d1eSTrond Myklebust { 12977f3a1d1eSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 12987f3a1d1eSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 12997f3a1d1eSTrond Myklebust 13007f3a1d1eSTrond Myklebust if (!test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) 13017f3a1d1eSTrond Myklebust return; 13027f3a1d1eSTrond Myklebust /* 13037f3a1d1eSTrond Myklebust * Sleep on the pending queue if we're expecting a reply. 13047f3a1d1eSTrond Myklebust * The spinlock ensures atomicity between the test of 13057f3a1d1eSTrond Myklebust * req->rq_reply_bytes_recvd, and the call to rpc_sleep_on(). 13067f3a1d1eSTrond Myklebust */ 13077f3a1d1eSTrond Myklebust spin_lock(&xprt->queue_lock); 13087f3a1d1eSTrond Myklebust if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) { 13098ba6a92dSTrond Myklebust xprt->ops->wait_for_reply_request(task); 13107f3a1d1eSTrond Myklebust /* 13117f3a1d1eSTrond Myklebust * Send an extra queue wakeup call if the 13127f3a1d1eSTrond Myklebust * connection was dropped in case the call to 13137f3a1d1eSTrond Myklebust * rpc_sleep_on() raced. 13147f3a1d1eSTrond Myklebust */ 13157f3a1d1eSTrond Myklebust if (xprt_request_retransmit_after_disconnect(task)) 13167f3a1d1eSTrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->pending, 13177f3a1d1eSTrond Myklebust task, -ENOTCONN); 13187f3a1d1eSTrond Myklebust } 13197f3a1d1eSTrond Myklebust spin_unlock(&xprt->queue_lock); 13207f3a1d1eSTrond Myklebust } 13217f3a1d1eSTrond Myklebust 1322944b0429STrond Myklebust static bool 1323944b0429STrond Myklebust xprt_request_need_enqueue_transmit(struct rpc_task *task, struct rpc_rqst *req) 1324944b0429STrond Myklebust { 1325762e4e67STrond Myklebust return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1326944b0429STrond Myklebust } 1327944b0429STrond Myklebust 1328944b0429STrond Myklebust /** 1329944b0429STrond Myklebust * xprt_request_enqueue_transmit - queue a task for transmission 1330944b0429STrond Myklebust * @task: pointer to rpc_task 1331944b0429STrond Myklebust * 1332944b0429STrond Myklebust * Add a task to the transmission queue. 1333944b0429STrond Myklebust */ 1334944b0429STrond Myklebust void 1335944b0429STrond Myklebust xprt_request_enqueue_transmit(struct rpc_task *task) 1336944b0429STrond Myklebust { 1337918f3c1fSTrond Myklebust struct rpc_rqst *pos, *req = task->tk_rqstp; 1338944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1339944b0429STrond Myklebust 1340944b0429STrond Myklebust if (xprt_request_need_enqueue_transmit(task, req)) { 1341e66721f0STrond Myklebust req->rq_bytes_sent = 0; 1342944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 134375891f50STrond Myklebust /* 134475891f50STrond Myklebust * Requests that carry congestion control credits are added 134575891f50STrond Myklebust * to the head of the list to avoid starvation issues. 134675891f50STrond Myklebust */ 134775891f50STrond Myklebust if (req->rq_cong) { 134875891f50STrond Myklebust xprt_clear_congestion_window_wait(xprt); 134975891f50STrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 135075891f50STrond Myklebust if (pos->rq_cong) 135175891f50STrond Myklebust continue; 135275891f50STrond Myklebust /* Note: req is added _before_ pos */ 135375891f50STrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 135475891f50STrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 135575891f50STrond Myklebust goto out; 135675891f50STrond Myklebust } 135786aeee0eSTrond Myklebust } else if (RPC_IS_SWAPPER(task)) { 135886aeee0eSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 135986aeee0eSTrond Myklebust if (pos->rq_cong || pos->rq_bytes_sent) 136086aeee0eSTrond Myklebust continue; 136186aeee0eSTrond Myklebust if (RPC_IS_SWAPPER(pos->rq_task)) 136286aeee0eSTrond Myklebust continue; 136386aeee0eSTrond Myklebust /* Note: req is added _before_ pos */ 136486aeee0eSTrond Myklebust list_add_tail(&req->rq_xmit, &pos->rq_xmit); 136586aeee0eSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 136686aeee0eSTrond Myklebust goto out; 136786aeee0eSTrond Myklebust } 1368deaa5c96SChuck Lever } else if (!req->rq_seqno) { 1369918f3c1fSTrond Myklebust list_for_each_entry(pos, &xprt->xmit_queue, rq_xmit) { 1370918f3c1fSTrond Myklebust if (pos->rq_task->tk_owner != task->tk_owner) 1371918f3c1fSTrond Myklebust continue; 1372918f3c1fSTrond Myklebust list_add_tail(&req->rq_xmit2, &pos->rq_xmit2); 1373918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit); 1374918f3c1fSTrond Myklebust goto out; 1375918f3c1fSTrond Myklebust } 137675891f50STrond Myklebust } 1377944b0429STrond Myklebust list_add_tail(&req->rq_xmit, &xprt->xmit_queue); 1378918f3c1fSTrond Myklebust INIT_LIST_HEAD(&req->rq_xmit2); 1379918f3c1fSTrond Myklebust out: 1380d737e5d4STrond Myklebust atomic_long_inc(&xprt->xmit_queuelen); 1381944b0429STrond Myklebust set_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1382944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1383944b0429STrond Myklebust } 1384944b0429STrond Myklebust } 1385944b0429STrond Myklebust 1386944b0429STrond Myklebust /** 1387944b0429STrond Myklebust * xprt_request_dequeue_transmit_locked - remove a task from the transmission queue 1388944b0429STrond Myklebust * @task: pointer to rpc_task 1389944b0429STrond Myklebust * 1390944b0429STrond Myklebust * Remove a task from the transmission queue 1391944b0429STrond Myklebust * Caller must hold xprt->queue_lock 1392944b0429STrond Myklebust */ 1393944b0429STrond Myklebust static void 1394944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(struct rpc_task *task) 1395944b0429STrond Myklebust { 1396918f3c1fSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1397918f3c1fSTrond Myklebust 1398918f3c1fSTrond Myklebust if (!test_and_clear_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 1399918f3c1fSTrond Myklebust return; 1400918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit)) { 1401918f3c1fSTrond Myklebust list_del(&req->rq_xmit); 1402918f3c1fSTrond Myklebust if (!list_empty(&req->rq_xmit2)) { 1403918f3c1fSTrond Myklebust struct rpc_rqst *next = list_first_entry(&req->rq_xmit2, 1404918f3c1fSTrond Myklebust struct rpc_rqst, rq_xmit2); 1405918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1406918f3c1fSTrond Myklebust list_add_tail(&next->rq_xmit, &next->rq_xprt->xmit_queue); 1407918f3c1fSTrond Myklebust } 1408918f3c1fSTrond Myklebust } else 1409918f3c1fSTrond Myklebust list_del(&req->rq_xmit2); 1410d737e5d4STrond Myklebust atomic_long_dec(&req->rq_xprt->xmit_queuelen); 1411944b0429STrond Myklebust } 1412944b0429STrond Myklebust 1413944b0429STrond Myklebust /** 1414944b0429STrond Myklebust * xprt_request_dequeue_transmit - remove a task from the transmission queue 1415944b0429STrond Myklebust * @task: pointer to rpc_task 1416944b0429STrond Myklebust * 1417944b0429STrond Myklebust * Remove a task from the transmission queue 1418944b0429STrond Myklebust */ 1419944b0429STrond Myklebust static void 1420944b0429STrond Myklebust xprt_request_dequeue_transmit(struct rpc_task *task) 1421944b0429STrond Myklebust { 1422944b0429STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1423944b0429STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1424944b0429STrond Myklebust 1425944b0429STrond Myklebust spin_lock(&xprt->queue_lock); 1426944b0429STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1427944b0429STrond Myklebust spin_unlock(&xprt->queue_lock); 1428944b0429STrond Myklebust } 1429944b0429STrond Myklebust 14307f3a1d1eSTrond Myklebust /** 1431cc204d01STrond Myklebust * xprt_request_dequeue_xprt - remove a task from the transmit+receive queue 1432cc204d01STrond Myklebust * @task: pointer to rpc_task 1433cc204d01STrond Myklebust * 1434cc204d01STrond Myklebust * Remove a task from the transmit and receive queues, and ensure that 1435cc204d01STrond Myklebust * it is not pinned by the receive work item. 1436cc204d01STrond Myklebust */ 1437cc204d01STrond Myklebust void 1438cc204d01STrond Myklebust xprt_request_dequeue_xprt(struct rpc_task *task) 1439cc204d01STrond Myklebust { 1440cc204d01STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 1441cc204d01STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1442cc204d01STrond Myklebust 1443cc204d01STrond Myklebust if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) || 1444cc204d01STrond Myklebust test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || 1445cc204d01STrond Myklebust xprt_is_pinned_rqst(req)) { 1446cc204d01STrond Myklebust spin_lock(&xprt->queue_lock); 1447cc204d01STrond Myklebust xprt_request_dequeue_transmit_locked(task); 1448cc204d01STrond Myklebust xprt_request_dequeue_receive_locked(task); 1449cc204d01STrond Myklebust while (xprt_is_pinned_rqst(req)) { 1450cc204d01STrond Myklebust set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1451cc204d01STrond Myklebust spin_unlock(&xprt->queue_lock); 1452cc204d01STrond Myklebust xprt_wait_on_pinned_rqst(req); 1453cc204d01STrond Myklebust spin_lock(&xprt->queue_lock); 1454cc204d01STrond Myklebust clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); 1455cc204d01STrond Myklebust } 1456cc204d01STrond Myklebust spin_unlock(&xprt->queue_lock); 1457cc204d01STrond Myklebust } 1458cc204d01STrond Myklebust } 1459cc204d01STrond Myklebust 1460cc204d01STrond Myklebust /** 14619d96acbcSTrond Myklebust * xprt_request_prepare - prepare an encoded request for transport 14629d96acbcSTrond Myklebust * @req: pointer to rpc_rqst 14639d96acbcSTrond Myklebust * 14649d96acbcSTrond Myklebust * Calls into the transport layer to do whatever is needed to prepare 14659d96acbcSTrond Myklebust * the request for transmission or receive. 14669d96acbcSTrond Myklebust */ 14679d96acbcSTrond Myklebust void 14689d96acbcSTrond Myklebust xprt_request_prepare(struct rpc_rqst *req) 14699d96acbcSTrond Myklebust { 14709d96acbcSTrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 14719d96acbcSTrond Myklebust 14729d96acbcSTrond Myklebust if (xprt->ops->prepare_request) 14739d96acbcSTrond Myklebust xprt->ops->prepare_request(req); 14749d96acbcSTrond Myklebust } 14759d96acbcSTrond Myklebust 14769d96acbcSTrond Myklebust /** 1477762e4e67STrond Myklebust * xprt_request_need_retransmit - Test if a task needs retransmission 1478762e4e67STrond Myklebust * @task: pointer to rpc_task 1479762e4e67STrond Myklebust * 1480762e4e67STrond Myklebust * Test for whether a connection breakage requires the task to retransmit 1481762e4e67STrond Myklebust */ 1482762e4e67STrond Myklebust bool 1483762e4e67STrond Myklebust xprt_request_need_retransmit(struct rpc_task *task) 1484762e4e67STrond Myklebust { 1485762e4e67STrond Myklebust return xprt_request_retransmit_after_disconnect(task); 1486762e4e67STrond Myklebust } 1487762e4e67STrond Myklebust 1488762e4e67STrond Myklebust /** 14899903cd1cSChuck Lever * xprt_prepare_transmit - reserve the transport before sending a request 14909903cd1cSChuck Lever * @task: RPC task about to send a request 14919903cd1cSChuck Lever * 14921da177e4SLinus Torvalds */ 149390051ea7STrond Myklebust bool xprt_prepare_transmit(struct rpc_task *task) 14941da177e4SLinus Torvalds { 14951da177e4SLinus Torvalds struct rpc_rqst *req = task->tk_rqstp; 14961da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 14971da177e4SLinus Torvalds 14985f2f6bd9STrond Myklebust if (!xprt_lock_write(xprt, task)) { 14995f2f6bd9STrond Myklebust /* Race breaker: someone may have transmitted us */ 1500944b0429STrond Myklebust if (!test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 15015f2f6bd9STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, 15025f2f6bd9STrond Myklebust task, 0); 15035f2f6bd9STrond Myklebust return false; 15045f2f6bd9STrond Myklebust 15058a19a0b6STrond Myklebust } 15065f2f6bd9STrond Myklebust return true; 15071da177e4SLinus Torvalds } 15081da177e4SLinus Torvalds 1509e0ab53deSTrond Myklebust void xprt_end_transmit(struct rpc_task *task) 15105e5ce5beSTrond Myklebust { 15117638e0bfSChuck Lever struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 15127638e0bfSChuck Lever 15137638e0bfSChuck Lever xprt_inject_disconnect(xprt); 15147638e0bfSChuck Lever xprt_release_write(xprt, task); 15155e5ce5beSTrond Myklebust } 15165e5ce5beSTrond Myklebust 15179903cd1cSChuck Lever /** 151889f90fe1STrond Myklebust * xprt_request_transmit - send an RPC request on a transport 151989f90fe1STrond Myklebust * @req: pointer to request to transmit 152089f90fe1STrond Myklebust * @snd_task: RPC task that owns the transport lock 15219903cd1cSChuck Lever * 152289f90fe1STrond Myklebust * This performs the transmission of a single request. 152389f90fe1STrond Myklebust * Note that if the request is not the same as snd_task, then it 152489f90fe1STrond Myklebust * does need to be pinned. 152589f90fe1STrond Myklebust * Returns '0' on success. 15269903cd1cSChuck Lever */ 152789f90fe1STrond Myklebust static int 152889f90fe1STrond Myklebust xprt_request_transmit(struct rpc_rqst *req, struct rpc_task *snd_task) 15291da177e4SLinus Torvalds { 15301da177e4SLinus Torvalds struct rpc_xprt *xprt = req->rq_xprt; 153189f90fe1STrond Myklebust struct rpc_task *task = req->rq_task; 153290d91b0cSTrond Myklebust unsigned int connect_cookie; 1533dcbbeda8STrond Myklebust int is_retrans = RPC_WAS_SENT(task); 1534ff699ea8SChuck Lever int status; 15351da177e4SLinus Torvalds 1536edc81dcdSTrond Myklebust if (!req->rq_bytes_sent) { 153789f90fe1STrond Myklebust if (xprt_request_data_received(task)) { 153889f90fe1STrond Myklebust status = 0; 1539944b0429STrond Myklebust goto out_dequeue; 154089f90fe1STrond Myklebust } 15413021a5bbSTrond Myklebust /* Verify that our message lies in the RPCSEC_GSS window */ 1542edc81dcdSTrond Myklebust if (rpcauth_xmit_need_reencode(task)) { 154389f90fe1STrond Myklebust status = -EBADMSG; 1544944b0429STrond Myklebust goto out_dequeue; 15453021a5bbSTrond Myklebust } 1546ae67bd38STrond Myklebust if (RPC_SIGNALLED(task)) { 1547ae67bd38STrond Myklebust status = -ERESTARTSYS; 1548ae67bd38STrond Myklebust goto out_dequeue; 1549ae67bd38STrond Myklebust } 15501da177e4SLinus Torvalds } 15511da177e4SLinus Torvalds 1552dcbbeda8STrond Myklebust /* 1553dcbbeda8STrond Myklebust * Update req->rq_ntrans before transmitting to avoid races with 1554dcbbeda8STrond Myklebust * xprt_update_rtt(), which needs to know that it is recording a 1555dcbbeda8STrond Myklebust * reply to the first transmission. 1556dcbbeda8STrond Myklebust */ 1557dcbbeda8STrond Myklebust req->rq_ntrans++; 1558dcbbeda8STrond Myklebust 1559c509f15aSChuck Lever trace_rpc_xdr_sendto(task, &req->rq_snd_buf); 156090d91b0cSTrond Myklebust connect_cookie = xprt->connect_cookie; 1561adfa7144STrond Myklebust status = xprt->ops->send_request(req); 1562c8485e4dSTrond Myklebust if (status != 0) { 1563dcbbeda8STrond Myklebust req->rq_ntrans--; 15640c77668dSChuck Lever trace_xprt_transmit(req, status); 156589f90fe1STrond Myklebust return status; 1566c8485e4dSTrond Myklebust } 15677ebbbc6eSTrond Myklebust 1568e936a597SChuck Lever if (is_retrans) { 1569dcbbeda8STrond Myklebust task->tk_client->cl_stats->rpcretrans++; 1570e936a597SChuck Lever trace_xprt_retransmit(req); 1571e936a597SChuck Lever } 1572dcbbeda8STrond Myklebust 15734a068258SChuck Lever xprt_inject_disconnect(xprt); 1574c8485e4dSTrond Myklebust 1575468f8613SBryan Schumaker task->tk_flags |= RPC_TASK_SENT; 1576b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 1577262ca07dSChuck Lever 1578262ca07dSChuck Lever xprt->stat.sends++; 1579262ca07dSChuck Lever xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; 1580262ca07dSChuck Lever xprt->stat.bklog_u += xprt->backlog.qlen; 158115a45206SAndy Adamson xprt->stat.sending_u += xprt->sending.qlen; 158215a45206SAndy Adamson xprt->stat.pending_u += xprt->pending.qlen; 1583b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 158490d91b0cSTrond Myklebust 158590d91b0cSTrond Myklebust req->rq_connect_cookie = connect_cookie; 1586944b0429STrond Myklebust out_dequeue: 15870c77668dSChuck Lever trace_xprt_transmit(req, status); 1588944b0429STrond Myklebust xprt_request_dequeue_transmit(task); 158989f90fe1STrond Myklebust rpc_wake_up_queued_task_set_status(&xprt->sending, task, status); 159089f90fe1STrond Myklebust return status; 159189f90fe1STrond Myklebust } 159289f90fe1STrond Myklebust 159389f90fe1STrond Myklebust /** 159489f90fe1STrond Myklebust * xprt_transmit - send an RPC request on a transport 159589f90fe1STrond Myklebust * @task: controlling RPC task 159689f90fe1STrond Myklebust * 159789f90fe1STrond Myklebust * Attempts to drain the transmit queue. On exit, either the transport 159889f90fe1STrond Myklebust * signalled an error that needs to be handled before transmission can 159989f90fe1STrond Myklebust * resume, or @task finished transmitting, and detected that it already 160089f90fe1STrond Myklebust * received a reply. 160189f90fe1STrond Myklebust */ 160289f90fe1STrond Myklebust void 160389f90fe1STrond Myklebust xprt_transmit(struct rpc_task *task) 160489f90fe1STrond Myklebust { 160589f90fe1STrond Myklebust struct rpc_rqst *next, *req = task->tk_rqstp; 160689f90fe1STrond Myklebust struct rpc_xprt *xprt = req->rq_xprt; 1607ea7a1019STrond Myklebust int status; 160889f90fe1STrond Myklebust 160989f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 1610ea7a1019STrond Myklebust for (;;) { 1611ea7a1019STrond Myklebust next = list_first_entry_or_null(&xprt->xmit_queue, 161289f90fe1STrond Myklebust struct rpc_rqst, rq_xmit); 1613ea7a1019STrond Myklebust if (!next) 1614ea7a1019STrond Myklebust break; 161589f90fe1STrond Myklebust xprt_pin_rqst(next); 161689f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 161789f90fe1STrond Myklebust status = xprt_request_transmit(next, task); 161889f90fe1STrond Myklebust if (status == -EBADMSG && next != req) 161989f90fe1STrond Myklebust status = 0; 162089f90fe1STrond Myklebust spin_lock(&xprt->queue_lock); 162189f90fe1STrond Myklebust xprt_unpin_rqst(next); 1622ea7a1019STrond Myklebust if (status < 0) { 1623ea7a1019STrond Myklebust if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 162489f90fe1STrond Myklebust task->tk_status = status; 162589f90fe1STrond Myklebust break; 162689f90fe1STrond Myklebust } 1627ea7a1019STrond Myklebust /* Was @task transmitted, and has it received a reply? */ 1628ea7a1019STrond Myklebust if (xprt_request_data_received(task) && 1629ea7a1019STrond Myklebust !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) 1630ea7a1019STrond Myklebust break; 1631ea7a1019STrond Myklebust cond_resched_lock(&xprt->queue_lock); 1632ea7a1019STrond Myklebust } 163389f90fe1STrond Myklebust spin_unlock(&xprt->queue_lock); 16341da177e4SLinus Torvalds } 16351da177e4SLinus Torvalds 1636e86be3a0STrond Myklebust static void xprt_complete_request_init(struct rpc_task *task) 1637e86be3a0STrond Myklebust { 1638e86be3a0STrond Myklebust if (task->tk_rqstp) 1639e86be3a0STrond Myklebust xprt_request_init(task); 1640e86be3a0STrond Myklebust } 1641e86be3a0STrond Myklebust 1642e86be3a0STrond Myklebust void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) 1643ba60eb25STrond Myklebust { 1644ba60eb25STrond Myklebust set_bit(XPRT_CONGESTED, &xprt->state); 1645e86be3a0STrond Myklebust rpc_sleep_on(&xprt->backlog, task, xprt_complete_request_init); 1646ba60eb25STrond Myklebust } 1647e86be3a0STrond Myklebust EXPORT_SYMBOL_GPL(xprt_add_backlog); 1648ba60eb25STrond Myklebust 1649e877a88dSNeilBrown static bool __xprt_set_rq(struct rpc_task *task, void *data) 1650ba60eb25STrond Myklebust { 1651e877a88dSNeilBrown struct rpc_rqst *req = data; 1652e877a88dSNeilBrown 1653e877a88dSNeilBrown if (task->tk_rqstp == NULL) { 1654e877a88dSNeilBrown memset(req, 0, sizeof(*req)); /* mark unused */ 1655e877a88dSNeilBrown task->tk_rqstp = req; 1656e877a88dSNeilBrown return true; 1657e877a88dSNeilBrown } 1658e877a88dSNeilBrown return false; 1659e877a88dSNeilBrown } 1660e877a88dSNeilBrown 1661e86be3a0STrond Myklebust bool xprt_wake_up_backlog(struct rpc_xprt *xprt, struct rpc_rqst *req) 1662e877a88dSNeilBrown { 1663e877a88dSNeilBrown if (rpc_wake_up_first(&xprt->backlog, __xprt_set_rq, req) == NULL) { 1664ba60eb25STrond Myklebust clear_bit(XPRT_CONGESTED, &xprt->state); 1665e877a88dSNeilBrown return false; 1666e877a88dSNeilBrown } 1667e877a88dSNeilBrown return true; 1668ba60eb25STrond Myklebust } 1669e86be3a0STrond Myklebust EXPORT_SYMBOL_GPL(xprt_wake_up_backlog); 1670ba60eb25STrond Myklebust 1671ba60eb25STrond Myklebust static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) 1672ba60eb25STrond Myklebust { 1673ba60eb25STrond Myklebust bool ret = false; 1674ba60eb25STrond Myklebust 1675ba60eb25STrond Myklebust if (!test_bit(XPRT_CONGESTED, &xprt->state)) 1676ba60eb25STrond Myklebust goto out; 1677ba60eb25STrond Myklebust spin_lock(&xprt->reserve_lock); 1678ba60eb25STrond Myklebust if (test_bit(XPRT_CONGESTED, &xprt->state)) { 1679e86be3a0STrond Myklebust xprt_add_backlog(xprt, task); 1680ba60eb25STrond Myklebust ret = true; 1681ba60eb25STrond Myklebust } 1682ba60eb25STrond Myklebust spin_unlock(&xprt->reserve_lock); 1683ba60eb25STrond Myklebust out: 1684ba60eb25STrond Myklebust return ret; 1685ba60eb25STrond Myklebust } 1686ba60eb25STrond Myklebust 168792ea011fSTrond Myklebust static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt) 1688d9ba131dSTrond Myklebust { 1689d9ba131dSTrond Myklebust struct rpc_rqst *req = ERR_PTR(-EAGAIN); 1690d9ba131dSTrond Myklebust 1691ff699ea8SChuck Lever if (xprt->num_reqs >= xprt->max_reqs) 1692d9ba131dSTrond Myklebust goto out; 1693ff699ea8SChuck Lever ++xprt->num_reqs; 169492ea011fSTrond Myklebust spin_unlock(&xprt->reserve_lock); 169592ea011fSTrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_NOFS); 169692ea011fSTrond Myklebust spin_lock(&xprt->reserve_lock); 1697d9ba131dSTrond Myklebust if (req != NULL) 1698d9ba131dSTrond Myklebust goto out; 1699ff699ea8SChuck Lever --xprt->num_reqs; 1700d9ba131dSTrond Myklebust req = ERR_PTR(-ENOMEM); 1701d9ba131dSTrond Myklebust out: 1702d9ba131dSTrond Myklebust return req; 1703d9ba131dSTrond Myklebust } 1704d9ba131dSTrond Myklebust 1705d9ba131dSTrond Myklebust static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1706d9ba131dSTrond Myklebust { 1707ff699ea8SChuck Lever if (xprt->num_reqs > xprt->min_reqs) { 1708ff699ea8SChuck Lever --xprt->num_reqs; 1709d9ba131dSTrond Myklebust kfree(req); 1710d9ba131dSTrond Myklebust return true; 1711d9ba131dSTrond Myklebust } 1712d9ba131dSTrond Myklebust return false; 1713d9ba131dSTrond Myklebust } 1714d9ba131dSTrond Myklebust 1715f39c1bfbSTrond Myklebust void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) 17161da177e4SLinus Torvalds { 1717d9ba131dSTrond Myklebust struct rpc_rqst *req; 17181da177e4SLinus Torvalds 1719f39c1bfbSTrond Myklebust spin_lock(&xprt->reserve_lock); 17201da177e4SLinus Torvalds if (!list_empty(&xprt->free)) { 1721d9ba131dSTrond Myklebust req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); 1722d9ba131dSTrond Myklebust list_del(&req->rq_list); 1723d9ba131dSTrond Myklebust goto out_init_req; 1724d9ba131dSTrond Myklebust } 172592ea011fSTrond Myklebust req = xprt_dynamic_alloc_slot(xprt); 1726d9ba131dSTrond Myklebust if (!IS_ERR(req)) 1727d9ba131dSTrond Myklebust goto out_init_req; 1728d9ba131dSTrond Myklebust switch (PTR_ERR(req)) { 1729d9ba131dSTrond Myklebust case -ENOMEM: 1730d9ba131dSTrond Myklebust dprintk("RPC: dynamic allocation of request slot " 1731d9ba131dSTrond Myklebust "failed! Retrying\n"); 17321afeaf5cSTrond Myklebust task->tk_status = -ENOMEM; 1733d9ba131dSTrond Myklebust break; 1734d9ba131dSTrond Myklebust case -EAGAIN: 1735ba60eb25STrond Myklebust xprt_add_backlog(xprt, task); 1736d9ba131dSTrond Myklebust dprintk("RPC: waiting for request slot\n"); 1737df561f66SGustavo A. R. Silva fallthrough; 17381afeaf5cSTrond Myklebust default: 1739d9ba131dSTrond Myklebust task->tk_status = -EAGAIN; 17401afeaf5cSTrond Myklebust } 1741f39c1bfbSTrond Myklebust spin_unlock(&xprt->reserve_lock); 1742d9ba131dSTrond Myklebust return; 1743d9ba131dSTrond Myklebust out_init_req: 1744ff699ea8SChuck Lever xprt->stat.max_slots = max_t(unsigned int, xprt->stat.max_slots, 1745ff699ea8SChuck Lever xprt->num_reqs); 174637ac86c3SChuck Lever spin_unlock(&xprt->reserve_lock); 174737ac86c3SChuck Lever 1748d9ba131dSTrond Myklebust task->tk_status = 0; 17491da177e4SLinus Torvalds task->tk_rqstp = req; 17501da177e4SLinus Torvalds } 1751f39c1bfbSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_alloc_slot); 1752f39c1bfbSTrond Myklebust 1753a9cde23aSChuck Lever void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) 1754ee5ebe85STrond Myklebust { 1755ee5ebe85STrond Myklebust spin_lock(&xprt->reserve_lock); 1756e877a88dSNeilBrown if (!xprt_wake_up_backlog(xprt, req) && 1757e877a88dSNeilBrown !xprt_dynamic_free_slot(xprt, req)) { 1758c25573b5STrond Myklebust memset(req, 0, sizeof(*req)); /* mark unused */ 1759ee5ebe85STrond Myklebust list_add(&req->rq_list, &xprt->free); 1760c25573b5STrond Myklebust } 1761ee5ebe85STrond Myklebust spin_unlock(&xprt->reserve_lock); 1762ee5ebe85STrond Myklebust } 1763a9cde23aSChuck Lever EXPORT_SYMBOL_GPL(xprt_free_slot); 1764ee5ebe85STrond Myklebust 176521de0a95STrond Myklebust static void xprt_free_all_slots(struct rpc_xprt *xprt) 176621de0a95STrond Myklebust { 176721de0a95STrond Myklebust struct rpc_rqst *req; 176821de0a95STrond Myklebust while (!list_empty(&xprt->free)) { 176921de0a95STrond Myklebust req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); 177021de0a95STrond Myklebust list_del(&req->rq_list); 177121de0a95STrond Myklebust kfree(req); 177221de0a95STrond Myklebust } 177321de0a95STrond Myklebust } 177421de0a95STrond Myklebust 1775572caba4SOlga Kornievskaia static DEFINE_IDA(rpc_xprt_ids); 1776572caba4SOlga Kornievskaia 1777572caba4SOlga Kornievskaia void xprt_cleanup_ids(void) 1778572caba4SOlga Kornievskaia { 1779572caba4SOlga Kornievskaia ida_destroy(&rpc_xprt_ids); 1780572caba4SOlga Kornievskaia } 1781572caba4SOlga Kornievskaia 1782572caba4SOlga Kornievskaia static int xprt_alloc_id(struct rpc_xprt *xprt) 1783572caba4SOlga Kornievskaia { 1784572caba4SOlga Kornievskaia int id; 1785572caba4SOlga Kornievskaia 1786572caba4SOlga Kornievskaia id = ida_simple_get(&rpc_xprt_ids, 0, 0, GFP_KERNEL); 1787572caba4SOlga Kornievskaia if (id < 0) 1788572caba4SOlga Kornievskaia return id; 1789572caba4SOlga Kornievskaia 1790572caba4SOlga Kornievskaia xprt->id = id; 1791572caba4SOlga Kornievskaia return 0; 1792572caba4SOlga Kornievskaia } 1793572caba4SOlga Kornievskaia 1794572caba4SOlga Kornievskaia static void xprt_free_id(struct rpc_xprt *xprt) 1795572caba4SOlga Kornievskaia { 1796572caba4SOlga Kornievskaia ida_simple_remove(&rpc_xprt_ids, xprt->id); 1797572caba4SOlga Kornievskaia } 1798572caba4SOlga Kornievskaia 1799d9ba131dSTrond Myklebust struct rpc_xprt *xprt_alloc(struct net *net, size_t size, 1800d9ba131dSTrond Myklebust unsigned int num_prealloc, 1801d9ba131dSTrond Myklebust unsigned int max_alloc) 1802bd1722d4SPavel Emelyanov { 1803bd1722d4SPavel Emelyanov struct rpc_xprt *xprt; 180421de0a95STrond Myklebust struct rpc_rqst *req; 180521de0a95STrond Myklebust int i; 1806bd1722d4SPavel Emelyanov 1807bd1722d4SPavel Emelyanov xprt = kzalloc(size, GFP_KERNEL); 1808bd1722d4SPavel Emelyanov if (xprt == NULL) 1809bd1722d4SPavel Emelyanov goto out; 1810bd1722d4SPavel Emelyanov 1811572caba4SOlga Kornievskaia xprt_alloc_id(xprt); 181221de0a95STrond Myklebust xprt_init(xprt, net); 181321de0a95STrond Myklebust 181421de0a95STrond Myklebust for (i = 0; i < num_prealloc; i++) { 181521de0a95STrond Myklebust req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); 181621de0a95STrond Myklebust if (!req) 18178313164cSwangweidong goto out_free; 181821de0a95STrond Myklebust list_add(&req->rq_list, &xprt->free); 181921de0a95STrond Myklebust } 1820d9ba131dSTrond Myklebust if (max_alloc > num_prealloc) 1821d9ba131dSTrond Myklebust xprt->max_reqs = max_alloc; 1822d9ba131dSTrond Myklebust else 182321de0a95STrond Myklebust xprt->max_reqs = num_prealloc; 1824d9ba131dSTrond Myklebust xprt->min_reqs = num_prealloc; 1825ff699ea8SChuck Lever xprt->num_reqs = num_prealloc; 1826bd1722d4SPavel Emelyanov 1827bd1722d4SPavel Emelyanov return xprt; 1828bd1722d4SPavel Emelyanov 1829bd1722d4SPavel Emelyanov out_free: 183021de0a95STrond Myklebust xprt_free(xprt); 1831bd1722d4SPavel Emelyanov out: 1832bd1722d4SPavel Emelyanov return NULL; 1833bd1722d4SPavel Emelyanov } 1834bd1722d4SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_alloc); 1835bd1722d4SPavel Emelyanov 1836e204e621SPavel Emelyanov void xprt_free(struct rpc_xprt *xprt) 1837e204e621SPavel Emelyanov { 183837aa2133SPavel Emelyanov put_net(xprt->xprt_net); 183921de0a95STrond Myklebust xprt_free_all_slots(xprt); 1840572caba4SOlga Kornievskaia xprt_free_id(xprt); 1841587bc725SOlga Kornievskaia rpc_sysfs_xprt_destroy(xprt); 1842fda1bfefSTrond Myklebust kfree_rcu(xprt, rcu); 1843e204e621SPavel Emelyanov } 1844e204e621SPavel Emelyanov EXPORT_SYMBOL_GPL(xprt_free); 1845e204e621SPavel Emelyanov 1846902c5887STrond Myklebust static void 1847902c5887STrond Myklebust xprt_init_connect_cookie(struct rpc_rqst *req, struct rpc_xprt *xprt) 1848902c5887STrond Myklebust { 1849902c5887STrond Myklebust req->rq_connect_cookie = xprt_connect_cookie(xprt) - 1; 1850902c5887STrond Myklebust } 1851902c5887STrond Myklebust 18529dc6edcfSTrond Myklebust static __be32 18539dc6edcfSTrond Myklebust xprt_alloc_xid(struct rpc_xprt *xprt) 18549dc6edcfSTrond Myklebust { 18559dc6edcfSTrond Myklebust __be32 xid; 18569dc6edcfSTrond Myklebust 18579dc6edcfSTrond Myklebust spin_lock(&xprt->reserve_lock); 18589dc6edcfSTrond Myklebust xid = (__force __be32)xprt->xid++; 18599dc6edcfSTrond Myklebust spin_unlock(&xprt->reserve_lock); 18609dc6edcfSTrond Myklebust return xid; 18619dc6edcfSTrond Myklebust } 18629dc6edcfSTrond Myklebust 18639dc6edcfSTrond Myklebust static void 18649dc6edcfSTrond Myklebust xprt_init_xid(struct rpc_xprt *xprt) 18659dc6edcfSTrond Myklebust { 18669dc6edcfSTrond Myklebust xprt->xid = prandom_u32(); 18679dc6edcfSTrond Myklebust } 18689dc6edcfSTrond Myklebust 18699dc6edcfSTrond Myklebust static void 18709dc6edcfSTrond Myklebust xprt_request_init(struct rpc_task *task) 18719dc6edcfSTrond Myklebust { 18729dc6edcfSTrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 18739dc6edcfSTrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 18749dc6edcfSTrond Myklebust 18759dc6edcfSTrond Myklebust req->rq_task = task; 18769dc6edcfSTrond Myklebust req->rq_xprt = xprt; 18779dc6edcfSTrond Myklebust req->rq_buffer = NULL; 18789dc6edcfSTrond Myklebust req->rq_xid = xprt_alloc_xid(xprt); 1879902c5887STrond Myklebust xprt_init_connect_cookie(req, xprt); 18809dc6edcfSTrond Myklebust req->rq_snd_buf.len = 0; 18819dc6edcfSTrond Myklebust req->rq_snd_buf.buflen = 0; 18829dc6edcfSTrond Myklebust req->rq_rcv_buf.len = 0; 18839dc6edcfSTrond Myklebust req->rq_rcv_buf.buflen = 0; 188471700bb9STrond Myklebust req->rq_snd_buf.bvec = NULL; 188571700bb9STrond Myklebust req->rq_rcv_buf.bvec = NULL; 18869dc6edcfSTrond Myklebust req->rq_release_snd_buf = NULL; 1887da953063STrond Myklebust xprt_init_majortimeo(task, req); 188809d2ba0cSChuck Lever 188909d2ba0cSChuck Lever trace_xprt_reserve(req); 18909dc6edcfSTrond Myklebust } 18919dc6edcfSTrond Myklebust 18929dc6edcfSTrond Myklebust static void 18939dc6edcfSTrond Myklebust xprt_do_reserve(struct rpc_xprt *xprt, struct rpc_task *task) 18949dc6edcfSTrond Myklebust { 18959dc6edcfSTrond Myklebust xprt->ops->alloc_slot(xprt, task); 18969dc6edcfSTrond Myklebust if (task->tk_rqstp != NULL) 18979dc6edcfSTrond Myklebust xprt_request_init(task); 18989dc6edcfSTrond Myklebust } 18999dc6edcfSTrond Myklebust 19009903cd1cSChuck Lever /** 19019903cd1cSChuck Lever * xprt_reserve - allocate an RPC request slot 19029903cd1cSChuck Lever * @task: RPC task requesting a slot allocation 19039903cd1cSChuck Lever * 1904ba60eb25STrond Myklebust * If the transport is marked as being congested, or if no more 1905ba60eb25STrond Myklebust * slots are available, place the task on the transport's 19069903cd1cSChuck Lever * backlog queue. 19079903cd1cSChuck Lever */ 19089903cd1cSChuck Lever void xprt_reserve(struct rpc_task *task) 19091da177e4SLinus Torvalds { 1910fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 19111da177e4SLinus Torvalds 191243cedbf0STrond Myklebust task->tk_status = 0; 191343cedbf0STrond Myklebust if (task->tk_rqstp != NULL) 191443cedbf0STrond Myklebust return; 191543cedbf0STrond Myklebust 191643cedbf0STrond Myklebust task->tk_status = -EAGAIN; 1917ba60eb25STrond Myklebust if (!xprt_throttle_congested(xprt, task)) 19189dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 1919ba60eb25STrond Myklebust } 1920ba60eb25STrond Myklebust 1921ba60eb25STrond Myklebust /** 1922ba60eb25STrond Myklebust * xprt_retry_reserve - allocate an RPC request slot 1923ba60eb25STrond Myklebust * @task: RPC task requesting a slot allocation 1924ba60eb25STrond Myklebust * 1925ba60eb25STrond Myklebust * If no more slots are available, place the task on the transport's 1926ba60eb25STrond Myklebust * backlog queue. 1927ba60eb25STrond Myklebust * Note that the only difference with xprt_reserve is that we now 1928ba60eb25STrond Myklebust * ignore the value of the XPRT_CONGESTED flag. 1929ba60eb25STrond Myklebust */ 1930ba60eb25STrond Myklebust void xprt_retry_reserve(struct rpc_task *task) 1931ba60eb25STrond Myklebust { 1932fb43d172STrond Myklebust struct rpc_xprt *xprt = task->tk_xprt; 1933ba60eb25STrond Myklebust 1934ba60eb25STrond Myklebust task->tk_status = 0; 1935e86be3a0STrond Myklebust if (task->tk_rqstp != NULL) 1936ba60eb25STrond Myklebust return; 1937ba60eb25STrond Myklebust 1938ba60eb25STrond Myklebust task->tk_status = -EAGAIN; 19399dc6edcfSTrond Myklebust xprt_do_reserve(xprt, task); 19401da177e4SLinus Torvalds } 19411da177e4SLinus Torvalds 19429903cd1cSChuck Lever /** 19439903cd1cSChuck Lever * xprt_release - release an RPC request slot 19449903cd1cSChuck Lever * @task: task which is finished with the slot 19459903cd1cSChuck Lever * 19461da177e4SLinus Torvalds */ 19479903cd1cSChuck Lever void xprt_release(struct rpc_task *task) 19481da177e4SLinus Torvalds { 194955ae1aabSRicardo Labiaga struct rpc_xprt *xprt; 195087ed5003STrond Myklebust struct rpc_rqst *req = task->tk_rqstp; 19511da177e4SLinus Torvalds 195287ed5003STrond Myklebust if (req == NULL) { 195387ed5003STrond Myklebust if (task->tk_client) { 1954fb43d172STrond Myklebust xprt = task->tk_xprt; 195587ed5003STrond Myklebust xprt_release_write(xprt, task); 195687ed5003STrond Myklebust } 19571da177e4SLinus Torvalds return; 195887ed5003STrond Myklebust } 195955ae1aabSRicardo Labiaga 196055ae1aabSRicardo Labiaga xprt = req->rq_xprt; 1961cc204d01STrond Myklebust xprt_request_dequeue_xprt(task); 1962b5e92419STrond Myklebust spin_lock(&xprt->transport_lock); 196349e9a890SChuck Lever xprt->ops->release_xprt(xprt, task); 1964a58dd398SChuck Lever if (xprt->ops->release_request) 1965a58dd398SChuck Lever xprt->ops->release_request(task); 1966ad3331acSTrond Myklebust xprt_schedule_autodisconnect(xprt); 1967b5e92419STrond Myklebust spin_unlock(&xprt->transport_lock); 1968ee5ebe85STrond Myklebust if (req->rq_buffer) 19693435c74aSChuck Lever xprt->ops->buf_free(task); 19709d96acbcSTrond Myklebust xdr_free_bvec(&req->rq_rcv_buf); 19710472e476STrond Myklebust xdr_free_bvec(&req->rq_snd_buf); 1972a17c2153STrond Myklebust if (req->rq_cred != NULL) 1973a17c2153STrond Myklebust put_rpccred(req->rq_cred); 1974ead5e1c2SJ. Bruce Fields if (req->rq_release_snd_buf) 1975ead5e1c2SJ. Bruce Fields req->rq_release_snd_buf(req); 197655ae1aabSRicardo Labiaga 1977e877a88dSNeilBrown task->tk_rqstp = NULL; 1978ee5ebe85STrond Myklebust if (likely(!bc_prealloc(req))) 1979a9cde23aSChuck Lever xprt->ops->free_slot(xprt, req); 1980ee5ebe85STrond Myklebust else 1981c9acb42eSTrond Myklebust xprt_free_bc_request(req); 19821da177e4SLinus Torvalds } 19831da177e4SLinus Torvalds 1984902c5887STrond Myklebust #ifdef CONFIG_SUNRPC_BACKCHANNEL 1985902c5887STrond Myklebust void 1986902c5887STrond Myklebust xprt_init_bc_request(struct rpc_rqst *req, struct rpc_task *task) 1987902c5887STrond Myklebust { 1988902c5887STrond Myklebust struct xdr_buf *xbufp = &req->rq_snd_buf; 1989902c5887STrond Myklebust 1990902c5887STrond Myklebust task->tk_rqstp = req; 1991902c5887STrond Myklebust req->rq_task = task; 1992902c5887STrond Myklebust xprt_init_connect_cookie(req, req->rq_xprt); 1993902c5887STrond Myklebust /* 1994902c5887STrond Myklebust * Set up the xdr_buf length. 1995902c5887STrond Myklebust * This also indicates that the buffer is XDR encoded already. 1996902c5887STrond Myklebust */ 1997902c5887STrond Myklebust xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1998902c5887STrond Myklebust xbufp->tail[0].iov_len; 1999902c5887STrond Myklebust } 2000902c5887STrond Myklebust #endif 2001902c5887STrond Myklebust 200221de0a95STrond Myklebust static void xprt_init(struct rpc_xprt *xprt, struct net *net) 2003c2866763SChuck Lever { 200430c5116bSTrond Myklebust kref_init(&xprt->kref); 2005c2866763SChuck Lever 2006c2866763SChuck Lever spin_lock_init(&xprt->transport_lock); 2007c2866763SChuck Lever spin_lock_init(&xprt->reserve_lock); 200875c84151STrond Myklebust spin_lock_init(&xprt->queue_lock); 2009c2866763SChuck Lever 2010c2866763SChuck Lever INIT_LIST_HEAD(&xprt->free); 201195f7691dSTrond Myklebust xprt->recv_queue = RB_ROOT; 2012944b0429STrond Myklebust INIT_LIST_HEAD(&xprt->xmit_queue); 20139e00abc3STrond Myklebust #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2014f9acac1aSRicardo Labiaga spin_lock_init(&xprt->bc_pa_lock); 2015f9acac1aSRicardo Labiaga INIT_LIST_HEAD(&xprt->bc_pa_list); 20169e00abc3STrond Myklebust #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 201780b14d5eSTrond Myklebust INIT_LIST_HEAD(&xprt->xprt_switch); 2018f9acac1aSRicardo Labiaga 2019c2866763SChuck Lever xprt->last_used = jiffies; 2020c2866763SChuck Lever xprt->cwnd = RPC_INITCWND; 2021a509050bSChuck Lever xprt->bind_index = 0; 2022c2866763SChuck Lever 2023c2866763SChuck Lever rpc_init_wait_queue(&xprt->binding, "xprt_binding"); 2024c2866763SChuck Lever rpc_init_wait_queue(&xprt->pending, "xprt_pending"); 202579c99152STrond Myklebust rpc_init_wait_queue(&xprt->sending, "xprt_sending"); 2026c2866763SChuck Lever rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); 2027c2866763SChuck Lever 2028c2866763SChuck Lever xprt_init_xid(xprt); 2029c2866763SChuck Lever 203021de0a95STrond Myklebust xprt->xprt_net = get_net(net); 20318d9266ffSTrond Myklebust } 20328d9266ffSTrond Myklebust 20338d9266ffSTrond Myklebust /** 20348d9266ffSTrond Myklebust * xprt_create_transport - create an RPC transport 20358d9266ffSTrond Myklebust * @args: rpc transport creation arguments 20368d9266ffSTrond Myklebust * 20378d9266ffSTrond Myklebust */ 20388d9266ffSTrond Myklebust struct rpc_xprt *xprt_create_transport(struct xprt_create *args) 20398d9266ffSTrond Myklebust { 20408d9266ffSTrond Myklebust struct rpc_xprt *xprt; 20419bccd264STrond Myklebust const struct xprt_class *t; 20428d9266ffSTrond Myklebust 20439bccd264STrond Myklebust t = xprt_class_find_by_ident(args->ident); 20449bccd264STrond Myklebust if (!t) { 20453c45ddf8SChuck Lever dprintk("RPC: transport (%d) not supported\n", args->ident); 20468d9266ffSTrond Myklebust return ERR_PTR(-EIO); 20479bccd264STrond Myklebust } 20488d9266ffSTrond Myklebust 20498d9266ffSTrond Myklebust xprt = t->setup(args); 20509bccd264STrond Myklebust xprt_class_release(t); 20519bccd264STrond Myklebust 2052911813d7SChuck Lever if (IS_ERR(xprt)) 205321de0a95STrond Myklebust goto out; 205433d90ac0SJ. Bruce Fields if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) 205533d90ac0SJ. Bruce Fields xprt->idle_timeout = 0; 205621de0a95STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_autoclose); 205721de0a95STrond Myklebust if (xprt_has_timer(xprt)) 2058502980e8SAnna Schumaker timer_setup(&xprt->timer, xprt_init_autodisconnect, 0); 205921de0a95STrond Myklebust else 2060ff861c4dSKees Cook timer_setup(&xprt->timer, NULL, 0); 20614e0038b6STrond Myklebust 20624e0038b6STrond Myklebust if (strlen(args->servername) > RPC_MAXNETNAMELEN) { 20634e0038b6STrond Myklebust xprt_destroy(xprt); 20644e0038b6STrond Myklebust return ERR_PTR(-EINVAL); 20654e0038b6STrond Myklebust } 20664e0038b6STrond Myklebust xprt->servername = kstrdup(args->servername, GFP_KERNEL); 20674e0038b6STrond Myklebust if (xprt->servername == NULL) { 20684e0038b6STrond Myklebust xprt_destroy(xprt); 20694e0038b6STrond Myklebust return ERR_PTR(-ENOMEM); 20704e0038b6STrond Myklebust } 20714e0038b6STrond Myklebust 20723f940098SJeff Layton rpc_xprt_debugfs_register(xprt); 2073388f0c77SJeff Layton 2074911813d7SChuck Lever trace_xprt_create(xprt); 207521de0a95STrond Myklebust out: 2076c2866763SChuck Lever return xprt; 2077c2866763SChuck Lever } 2078c2866763SChuck Lever 2079528fd354STrond Myklebust static void xprt_destroy_cb(struct work_struct *work) 2080528fd354STrond Myklebust { 2081528fd354STrond Myklebust struct rpc_xprt *xprt = 2082528fd354STrond Myklebust container_of(work, struct rpc_xprt, task_cleanup); 2083528fd354STrond Myklebust 2084911813d7SChuck Lever trace_xprt_destroy(xprt); 2085911813d7SChuck Lever 2086528fd354STrond Myklebust rpc_xprt_debugfs_unregister(xprt); 2087528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->binding); 2088528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->pending); 2089528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->sending); 2090528fd354STrond Myklebust rpc_destroy_wait_queue(&xprt->backlog); 2091528fd354STrond Myklebust kfree(xprt->servername); 2092528fd354STrond Myklebust /* 2093669996adSTrond Myklebust * Destroy any existing back channel 2094669996adSTrond Myklebust */ 2095669996adSTrond Myklebust xprt_destroy_backchannel(xprt, UINT_MAX); 2096669996adSTrond Myklebust 2097669996adSTrond Myklebust /* 2098528fd354STrond Myklebust * Tear down transport state and free the rpc_xprt 2099528fd354STrond Myklebust */ 2100528fd354STrond Myklebust xprt->ops->destroy(xprt); 2101528fd354STrond Myklebust } 2102528fd354STrond Myklebust 21039903cd1cSChuck Lever /** 21049903cd1cSChuck Lever * xprt_destroy - destroy an RPC transport, killing off all requests. 2105a8de240aSTrond Myklebust * @xprt: transport to destroy 21069903cd1cSChuck Lever * 21071da177e4SLinus Torvalds */ 2108a8de240aSTrond Myklebust static void xprt_destroy(struct rpc_xprt *xprt) 21091da177e4SLinus Torvalds { 2110528fd354STrond Myklebust /* 2111528fd354STrond Myklebust * Exclude transport connect/disconnect handlers and autoclose 2112528fd354STrond Myklebust */ 211379234c3dSTrond Myklebust wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); 211479234c3dSTrond Myklebust 21150065db32STrond Myklebust del_timer_sync(&xprt->timer); 2116c8541ecdSChuck Lever 2117c8541ecdSChuck Lever /* 2118528fd354STrond Myklebust * Destroy sockets etc from the system workqueue so they can 2119528fd354STrond Myklebust * safely flush receive work running on rpciod. 2120c8541ecdSChuck Lever */ 2121528fd354STrond Myklebust INIT_WORK(&xprt->task_cleanup, xprt_destroy_cb); 2122528fd354STrond Myklebust schedule_work(&xprt->task_cleanup); 21236b6ca86bSTrond Myklebust } 21241da177e4SLinus Torvalds 212530c5116bSTrond Myklebust static void xprt_destroy_kref(struct kref *kref) 212630c5116bSTrond Myklebust { 212730c5116bSTrond Myklebust xprt_destroy(container_of(kref, struct rpc_xprt, kref)); 212830c5116bSTrond Myklebust } 212930c5116bSTrond Myklebust 213030c5116bSTrond Myklebust /** 213130c5116bSTrond Myklebust * xprt_get - return a reference to an RPC transport. 213230c5116bSTrond Myklebust * @xprt: pointer to the transport 213330c5116bSTrond Myklebust * 213430c5116bSTrond Myklebust */ 213530c5116bSTrond Myklebust struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 213630c5116bSTrond Myklebust { 213730c5116bSTrond Myklebust if (xprt != NULL && kref_get_unless_zero(&xprt->kref)) 213830c5116bSTrond Myklebust return xprt; 213930c5116bSTrond Myklebust return NULL; 214030c5116bSTrond Myklebust } 214130c5116bSTrond Myklebust EXPORT_SYMBOL_GPL(xprt_get); 214230c5116bSTrond Myklebust 21436b6ca86bSTrond Myklebust /** 21446b6ca86bSTrond Myklebust * xprt_put - release a reference to an RPC transport. 21456b6ca86bSTrond Myklebust * @xprt: pointer to the transport 21466b6ca86bSTrond Myklebust * 21476b6ca86bSTrond Myklebust */ 21486b6ca86bSTrond Myklebust void xprt_put(struct rpc_xprt *xprt) 21496b6ca86bSTrond Myklebust { 215030c5116bSTrond Myklebust if (xprt != NULL) 215130c5116bSTrond Myklebust kref_put(&xprt->kref, xprt_destroy_kref); 21526b6ca86bSTrond Myklebust } 21535d252f90SChuck Lever EXPORT_SYMBOL_GPL(xprt_put); 2154