blob: bd462a532acfa695906887db429896ae569eac26 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/net/sunrpc/xprt.c
3 *
4 * This is a generic RPC call interface supporting congestion avoidance,
5 * and asynchronous calls.
6 *
7 * The interface works like this:
8 *
9 * - When a process places a call, it allocates a request slot if
10 * one is available. Otherwise, it sleeps on the backlog queue
11 * (xprt_reserve).
12 * - Next, the caller puts together the RPC message, stuffs it into
Chuck Lever55aa4f52005-08-11 16:25:47 -040013 * the request struct, and calls xprt_transmit().
14 * - xprt_transmit sends the message and installs the caller on the
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -040015 * transport's wait list. At the same time, if a reply is expected,
16 * it installs a timer that is run after the packet's timeout has
17 * expired.
Linus Torvalds1da177e2005-04-16 15:20:36 -070018 * - When a packet arrives, the data_ready handler walks the list of
Chuck Lever55aa4f52005-08-11 16:25:47 -040019 * pending requests for that transport. If a matching XID is found, the
Linus Torvalds1da177e2005-04-16 15:20:36 -070020 * caller is woken up, and the timer removed.
21 * - When no reply arrives within the timeout interval, the timer is
22 * fired by the kernel and runs xprt_timer(). It either adjusts the
23 * timeout values (minor timeout) or wakes up the caller with a status
24 * of -ETIMEDOUT.
25 * - When the caller receives a notification from RPC that a reply arrived,
26 * it should release the RPC slot, and process the reply.
27 * If the call timed out, it may choose to retry the operation by
28 * adjusting the initial timeout value, and simply calling rpc_call
29 * again.
30 *
31 * Support for async RPC is done through a set of RPC-specific scheduling
32 * primitives that `transparently' work for processes as well as async
33 * tasks that rely on callbacks.
34 *
35 * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de>
Chuck Lever55aa4f52005-08-11 16:25:47 -040036 *
37 * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 */
39
Chuck Levera246b012005-08-11 16:25:23 -040040#include <linux/module.h>
41
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/types.h>
Chuck Levera246b012005-08-11 16:25:23 -040043#include <linux/interrupt.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/workqueue.h>
Chuck Leverbf3fcf82006-05-25 01:40:51 -040045#include <linux/net.h>
Chuck Leverff839972010-05-07 13:34:47 -040046#include <linux/ktime.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
Chuck Levera246b012005-08-11 16:25:23 -040048#include <linux/sunrpc/clnt.h>
Chuck Lever11c556b2006-03-20 13:44:22 -050049#include <linux/sunrpc/metrics.h>
Trond Myklebustc9acb422010-03-19 15:36:22 -040050#include <linux/sunrpc/bc_xprt.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -040052#include "sunrpc.h"
53
Linus Torvalds1da177e2005-04-16 15:20:36 -070054/*
55 * Local variables
56 */
57
58#ifdef RPC_DEBUG
Linus Torvalds1da177e2005-04-16 15:20:36 -070059# define RPCDBG_FACILITY RPCDBG_XPRT
60#endif
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062/*
63 * Local functions
64 */
Trond Myklebust21de0a92011-07-17 16:57:32 -040065static void xprt_init(struct rpc_xprt *xprt, struct net *net);
Linus Torvalds1da177e2005-04-16 15:20:36 -070066static void xprt_request_init(struct rpc_task *, struct rpc_xprt *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067static void xprt_connect_status(struct rpc_task *task);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *);
Trond Myklebust4e0038b2012-03-01 17:01:05 -050069static void xprt_destroy(struct rpc_xprt *xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070
Jiri Slaby5ba03e82007-11-22 19:40:22 +080071static DEFINE_SPINLOCK(xprt_list_lock);
\"Talpey, Thomas\81c098a2007-09-10 13:46:00 -040072static LIST_HEAD(xprt_list);
73
Chuck Lever555ee3a2005-08-25 16:25:54 -070074/*
75 * The transport code maintains an estimate on the maximum number of out-
76 * standing RPC requests, using a smoothed version of the congestion
77 * avoidance implemented in 44BSD. This is basically the Van Jacobson
78 * congestion algorithm: If a retransmit occurs, the congestion window is
79 * halved; otherwise, it is incremented by 1/cwnd when
80 *
81 * - a reply is received and
82 * - a full number of requests are outstanding and
83 * - the congestion window hasn't been updated recently.
84 */
85#define RPC_CWNDSHIFT (8U)
86#define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT)
87#define RPC_INITCWND RPC_CWNDSCALE
88#define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT)
89
90#define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
Chuck Lever12a80462005-08-25 16:25:51 -070092/**
\"Talpey, Thomas\81c098a2007-09-10 13:46:00 -040093 * xprt_register_transport - register a transport implementation
94 * @transport: transport to register
95 *
96 * If a transport implementation is loaded as a kernel module, it can
97 * call this interface to make itself known to the RPC client.
98 *
99 * Returns:
100 * 0: transport successfully registered
101 * -EEXIST: transport already registered
102 * -EINVAL: transport module being unloaded
103 */
104int xprt_register_transport(struct xprt_class *transport)
105{
106 struct xprt_class *t;
107 int result;
108
109 result = -EEXIST;
110 spin_lock(&xprt_list_lock);
111 list_for_each_entry(t, &xprt_list, list) {
112 /* don't register the same transport class twice */
\"Talpey, Thomas\4fa016e2007-09-10 13:47:57 -0400113 if (t->ident == transport->ident)
\"Talpey, Thomas\81c098a2007-09-10 13:46:00 -0400114 goto out;
115 }
116
Denis V. Lunevc9f6cde2008-07-31 09:53:56 +0400117 list_add_tail(&transport->list, &xprt_list);
118 printk(KERN_INFO "RPC: Registered %s transport module.\n",
119 transport->name);
120 result = 0;
\"Talpey, Thomas\81c098a2007-09-10 13:46:00 -0400121
122out:
123 spin_unlock(&xprt_list_lock);
124 return result;
125}
126EXPORT_SYMBOL_GPL(xprt_register_transport);
127
128/**
129 * xprt_unregister_transport - unregister a transport implementation
Randy Dunlap65b6e422008-02-13 15:03:23 -0800130 * @transport: transport to unregister
\"Talpey, Thomas\81c098a2007-09-10 13:46:00 -0400131 *
132 * Returns:
133 * 0: transport successfully unregistered
134 * -ENOENT: transport never registered
135 */
136int xprt_unregister_transport(struct xprt_class *transport)
137{
138 struct xprt_class *t;
139 int result;
140
141 result = 0;
142 spin_lock(&xprt_list_lock);
143 list_for_each_entry(t, &xprt_list, list) {
144 if (t == transport) {
145 printk(KERN_INFO
146 "RPC: Unregistered %s transport module.\n",
147 transport->name);
148 list_del_init(&transport->list);
\"Talpey, Thomas\81c098a2007-09-10 13:46:00 -0400149 goto out;
150 }
151 }
152 result = -ENOENT;
153
154out:
155 spin_unlock(&xprt_list_lock);
156 return result;
157}
158EXPORT_SYMBOL_GPL(xprt_unregister_transport);
159
160/**
Tom Talpey441e3e22009-03-11 14:37:56 -0400161 * xprt_load_transport - load a transport implementation
162 * @transport_name: transport to load
163 *
164 * Returns:
165 * 0: transport successfully loaded
166 * -ENOENT: transport module not available
167 */
168int xprt_load_transport(const char *transport_name)
169{
170 struct xprt_class *t;
Tom Talpey441e3e22009-03-11 14:37:56 -0400171 int result;
172
173 result = 0;
174 spin_lock(&xprt_list_lock);
175 list_for_each_entry(t, &xprt_list, list) {
176 if (strcmp(t->name, transport_name) == 0) {
177 spin_unlock(&xprt_list_lock);
178 goto out;
179 }
180 }
181 spin_unlock(&xprt_list_lock);
Alex Riesenef7ffe82010-05-24 14:33:05 -0700182 result = request_module("xprt%s", transport_name);
Tom Talpey441e3e22009-03-11 14:37:56 -0400183out:
184 return result;
185}
186EXPORT_SYMBOL_GPL(xprt_load_transport);
187
188/**
Chuck Lever12a80462005-08-25 16:25:51 -0700189 * xprt_reserve_xprt - serialize write access to transports
190 * @task: task that is requesting access to the transport
Randy Dunlap177c27b2011-07-28 06:54:36 +0000191 * @xprt: pointer to the target transport
Chuck Lever12a80462005-08-25 16:25:51 -0700192 *
193 * This prevents mixing the payload of separate requests, and prevents
194 * transport connects from colliding with writes. No congestion control
195 * is provided.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 */
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400197int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198{
Chuck Lever12a80462005-08-25 16:25:51 -0700199 struct rpc_rqst *req = task->tk_rqstp;
Trond Myklebust34006ce2011-07-17 18:11:34 -0400200 int priority;
Chuck Lever12a80462005-08-25 16:25:51 -0700201
202 if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
203 if (task == xprt->snd_task)
204 return 1;
Chuck Lever12a80462005-08-25 16:25:51 -0700205 goto out_sleep;
206 }
207 xprt->snd_task = task;
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400208 if (req != NULL) {
209 req->rq_bytes_sent = 0;
210 req->rq_ntrans++;
211 }
j223yang@asset.uwaterloo.ca4d4a76f2011-03-10 12:40:28 -0500212
Chuck Lever12a80462005-08-25 16:25:51 -0700213 return 1;
214
215out_sleep:
Chuck Lever46121cf2007-01-31 12:14:08 -0500216 dprintk("RPC: %5u failed to lock transport %p\n",
Chuck Lever12a80462005-08-25 16:25:51 -0700217 task->tk_pid, xprt);
218 task->tk_timeout = 0;
219 task->tk_status = -EAGAIN;
Trond Myklebust34006ce2011-07-17 18:11:34 -0400220 if (req == NULL)
221 priority = RPC_PRIORITY_LOW;
222 else if (!req->rq_ntrans)
223 priority = RPC_PRIORITY_NORMAL;
Chuck Lever12a80462005-08-25 16:25:51 -0700224 else
Trond Myklebust34006ce2011-07-17 18:11:34 -0400225 priority = RPC_PRIORITY_HIGH;
226 rpc_sleep_on_priority(&xprt->sending, task, NULL, priority);
Chuck Lever12a80462005-08-25 16:25:51 -0700227 return 0;
228}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400229EXPORT_SYMBOL_GPL(xprt_reserve_xprt);
Chuck Lever12a80462005-08-25 16:25:51 -0700230
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100231static void xprt_clear_locked(struct rpc_xprt *xprt)
232{
233 xprt->snd_task = NULL;
Trond Myklebustd19751e2012-09-11 17:21:25 -0400234 if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) {
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100235 smp_mb__before_clear_bit();
236 clear_bit(XPRT_LOCKED, &xprt->state);
237 smp_mb__after_clear_bit();
238 } else
Trond Myklebustc1384c92007-06-14 18:00:42 -0400239 queue_work(rpciod_workqueue, &xprt->task_cleanup);
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100240}
241
Chuck Lever12a80462005-08-25 16:25:51 -0700242/*
243 * xprt_reserve_xprt_cong - serialize write access to transports
244 * @task: task that is requesting access to the transport
245 *
246 * Same as xprt_reserve_xprt, but Van Jacobson congestion control is
247 * integrated into the decision of whether a request is allowed to be
248 * woken up and given access to the transport.
249 */
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400250int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task)
Chuck Lever12a80462005-08-25 16:25:51 -0700251{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 struct rpc_rqst *req = task->tk_rqstp;
Trond Myklebust34006ce2011-07-17 18:11:34 -0400253 int priority;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254
Chuck Lever2226feb2005-08-11 16:25:38 -0400255 if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 if (task == xprt->snd_task)
257 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 goto out_sleep;
259 }
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400260 if (req == NULL) {
261 xprt->snd_task = task;
262 return 1;
263 }
Chuck Lever12a80462005-08-25 16:25:51 -0700264 if (__xprt_get_cong(xprt, task)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 xprt->snd_task = task;
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400266 req->rq_bytes_sent = 0;
267 req->rq_ntrans++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 return 1;
269 }
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100270 xprt_clear_locked(xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271out_sleep:
Chuck Lever46121cf2007-01-31 12:14:08 -0500272 dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273 task->tk_timeout = 0;
274 task->tk_status = -EAGAIN;
Trond Myklebust34006ce2011-07-17 18:11:34 -0400275 if (req == NULL)
276 priority = RPC_PRIORITY_LOW;
277 else if (!req->rq_ntrans)
278 priority = RPC_PRIORITY_NORMAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 else
Trond Myklebust34006ce2011-07-17 18:11:34 -0400280 priority = RPC_PRIORITY_HIGH;
281 rpc_sleep_on_priority(&xprt->sending, task, NULL, priority);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 return 0;
283}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400284EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285
Chuck Lever12a80462005-08-25 16:25:51 -0700286static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287{
288 int retval;
289
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400290 spin_lock_bh(&xprt->transport_lock);
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400291 retval = xprt->ops->reserve_xprt(xprt, task);
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400292 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 return retval;
294}
295
Trond Myklebust961a8282012-01-17 22:57:37 -0500296static bool __xprt_lock_write_func(struct rpc_task *task, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297{
Trond Myklebust961a8282012-01-17 22:57:37 -0500298 struct rpc_xprt *xprt = data;
Chuck Lever49e9a892005-08-25 16:25:51 -0700299 struct rpc_rqst *req;
300
Chuck Lever49e9a892005-08-25 16:25:51 -0700301 req = task->tk_rqstp;
302 xprt->snd_task = task;
303 if (req) {
304 req->rq_bytes_sent = 0;
305 req->rq_ntrans++;
306 }
Trond Myklebust961a8282012-01-17 22:57:37 -0500307 return true;
308}
Chuck Lever49e9a892005-08-25 16:25:51 -0700309
Trond Myklebust961a8282012-01-17 22:57:37 -0500310static void __xprt_lock_write_next(struct rpc_xprt *xprt)
311{
312 if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
313 return;
314
315 if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt))
316 return;
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100317 xprt_clear_locked(xprt);
Chuck Lever49e9a892005-08-25 16:25:51 -0700318}
319
Trond Myklebust961a8282012-01-17 22:57:37 -0500320static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data)
Chuck Lever49e9a892005-08-25 16:25:51 -0700321{
Trond Myklebust961a8282012-01-17 22:57:37 -0500322 struct rpc_xprt *xprt = data;
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400323 struct rpc_rqst *req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400325 req = task->tk_rqstp;
326 if (req == NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 xprt->snd_task = task;
Trond Myklebust961a8282012-01-17 22:57:37 -0500328 return true;
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400329 }
330 if (__xprt_get_cong(xprt, task)) {
331 xprt->snd_task = task;
332 req->rq_bytes_sent = 0;
333 req->rq_ntrans++;
Trond Myklebust961a8282012-01-17 22:57:37 -0500334 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 }
Trond Myklebust961a8282012-01-17 22:57:37 -0500336 return false;
337}
338
339static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt)
340{
341 if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
342 return;
343 if (RPCXPRT_CONGESTED(xprt))
344 goto out_unlock;
345 if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt))
346 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347out_unlock:
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100348 xprt_clear_locked(xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349}
350
Chuck Lever49e9a892005-08-25 16:25:51 -0700351/**
352 * xprt_release_xprt - allow other requests to use a transport
353 * @xprt: transport with other tasks potentially waiting
354 * @task: task that is releasing access to the transport
355 *
356 * Note that "task" can be NULL. No congestion control is provided.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 */
Chuck Lever49e9a892005-08-25 16:25:51 -0700358void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359{
360 if (xprt->snd_task == task) {
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100361 xprt_clear_locked(xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 __xprt_lock_write_next(xprt);
363 }
364}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400365EXPORT_SYMBOL_GPL(xprt_release_xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
Chuck Lever49e9a892005-08-25 16:25:51 -0700367/**
368 * xprt_release_xprt_cong - allow other requests to use a transport
369 * @xprt: transport with other tasks potentially waiting
370 * @task: task that is releasing access to the transport
371 *
372 * Note that "task" can be NULL. Another task is awoken to use the
373 * transport if the transport's congestion window allows it.
374 */
375void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task)
376{
377 if (xprt->snd_task == task) {
Trond Myklebust632e3bd2006-01-03 09:55:55 +0100378 xprt_clear_locked(xprt);
Chuck Lever49e9a892005-08-25 16:25:51 -0700379 __xprt_lock_write_next_cong(xprt);
380 }
381}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400382EXPORT_SYMBOL_GPL(xprt_release_xprt_cong);
Chuck Lever49e9a892005-08-25 16:25:51 -0700383
384static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385{
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400386 spin_lock_bh(&xprt->transport_lock);
Chuck Lever49e9a892005-08-25 16:25:51 -0700387 xprt->ops->release_xprt(xprt, task);
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400388 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389}
390
391/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 * Van Jacobson congestion avoidance. Check if the congestion window
393 * overflowed. Put the task to sleep if this is the case.
394 */
395static int
396__xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task)
397{
398 struct rpc_rqst *req = task->tk_rqstp;
399
400 if (req->rq_cong)
401 return 1;
Chuck Lever46121cf2007-01-31 12:14:08 -0500402 dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 task->tk_pid, xprt->cong, xprt->cwnd);
404 if (RPCXPRT_CONGESTED(xprt))
405 return 0;
406 req->rq_cong = 1;
407 xprt->cong += RPC_CWNDSCALE;
408 return 1;
409}
410
411/*
412 * Adjust the congestion window, and wake up the next task
413 * that has been sleeping due to congestion
414 */
415static void
416__xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req)
417{
418 if (!req->rq_cong)
419 return;
420 req->rq_cong = 0;
421 xprt->cong -= RPC_CWNDSCALE;
Chuck Lever49e9a892005-08-25 16:25:51 -0700422 __xprt_lock_write_next_cong(xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423}
424
Chuck Lever46c0ee82005-08-25 16:25:52 -0700425/**
Chuck Levera58dd392005-08-25 16:25:53 -0700426 * xprt_release_rqst_cong - housekeeping when request is complete
427 * @task: RPC request that recently completed
428 *
429 * Useful for transports that require congestion control.
430 */
431void xprt_release_rqst_cong(struct rpc_task *task)
432{
433 __xprt_put_cong(task->tk_xprt, task->tk_rqstp);
434}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400435EXPORT_SYMBOL_GPL(xprt_release_rqst_cong);
Chuck Levera58dd392005-08-25 16:25:53 -0700436
437/**
Chuck Lever46c0ee82005-08-25 16:25:52 -0700438 * xprt_adjust_cwnd - adjust transport congestion window
439 * @task: recently completed RPC request used to adjust window
440 * @result: result code of completed RPC request
441 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 * We use a time-smoothed congestion estimator to avoid heavy oscillation.
443 */
Chuck Lever46c0ee82005-08-25 16:25:52 -0700444void xprt_adjust_cwnd(struct rpc_task *task, int result)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445{
Chuck Lever46c0ee82005-08-25 16:25:52 -0700446 struct rpc_rqst *req = task->tk_rqstp;
447 struct rpc_xprt *xprt = task->tk_xprt;
448 unsigned long cwnd = xprt->cwnd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 if (result >= 0 && cwnd <= xprt->cong) {
451 /* The (cwnd >> 1) term makes sure
452 * the result gets rounded properly. */
453 cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd;
454 if (cwnd > RPC_MAXCWND(xprt))
455 cwnd = RPC_MAXCWND(xprt);
Chuck Lever49e9a892005-08-25 16:25:51 -0700456 __xprt_lock_write_next_cong(xprt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 } else if (result == -ETIMEDOUT) {
458 cwnd >>= 1;
459 if (cwnd < RPC_CWNDSCALE)
460 cwnd = RPC_CWNDSCALE;
461 }
Chuck Lever46121cf2007-01-31 12:14:08 -0500462 dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 xprt->cong, xprt->cwnd, cwnd);
464 xprt->cwnd = cwnd;
Chuck Lever46c0ee82005-08-25 16:25:52 -0700465 __xprt_put_cong(xprt, req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400467EXPORT_SYMBOL_GPL(xprt_adjust_cwnd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468
Chuck Lever44fbac22005-08-11 16:25:44 -0400469/**
470 * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue
471 * @xprt: transport with waiting tasks
472 * @status: result code to plant in each task before waking it
473 *
474 */
475void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status)
476{
477 if (status < 0)
478 rpc_wake_up_status(&xprt->pending, status);
479 else
480 rpc_wake_up(&xprt->pending);
481}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400482EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks);
Chuck Lever44fbac22005-08-11 16:25:44 -0400483
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400484/**
485 * xprt_wait_for_buffer_space - wait for transport output buffer to clear
486 * @task: task to be put to sleep
Randy Dunlap0b80ae42008-04-26 22:59:02 -0700487 * @action: function pointer to be executed after wait
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400488 */
Trond Myklebustb6ddf642008-04-17 18:52:19 -0400489void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action)
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400490{
491 struct rpc_rqst *req = task->tk_rqstp;
492 struct rpc_xprt *xprt = req->rq_xprt;
493
494 task->tk_timeout = req->rq_timeout;
Trond Myklebustb6ddf642008-04-17 18:52:19 -0400495 rpc_sleep_on(&xprt->pending, task, action);
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400496}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400497EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space);
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400498
499/**
500 * xprt_write_space - wake the task waiting for transport output buffer space
501 * @xprt: transport with waiting tasks
502 *
503 * Can be called in a soft IRQ context, so xprt_write_space never sleeps.
504 */
505void xprt_write_space(struct rpc_xprt *xprt)
506{
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400507 spin_lock_bh(&xprt->transport_lock);
508 if (xprt->snd_task) {
Chuck Lever46121cf2007-01-31 12:14:08 -0500509 dprintk("RPC: write space: waking waiting task on "
510 "xprt %p\n", xprt);
Trond Myklebustfda13932008-02-22 16:34:12 -0500511 rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task);
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400512 }
513 spin_unlock_bh(&xprt->transport_lock);
514}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400515EXPORT_SYMBOL_GPL(xprt_write_space);
Chuck Leverc7b2cae2005-08-11 16:25:50 -0400516
Chuck Leverfe3aca22005-08-25 16:25:50 -0700517/**
518 * xprt_set_retrans_timeout_def - set a request's retransmit timeout
519 * @task: task whose timeout is to be set
520 *
521 * Set a request's retransmit timeout based on the transport's
522 * default timeout parameters. Used by transports that don't adjust
523 * the retransmit timeout based on round-trip time estimation.
524 */
525void xprt_set_retrans_timeout_def(struct rpc_task *task)
526{
527 task->tk_timeout = task->tk_rqstp->rq_timeout;
528}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400529EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def);
Chuck Leverfe3aca22005-08-25 16:25:50 -0700530
Ben Hutchings2c530402012-07-10 10:55:09 +0000531/**
Chuck Leverfe3aca22005-08-25 16:25:50 -0700532 * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout
533 * @task: task whose timeout is to be set
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800534 *
Chuck Leverfe3aca22005-08-25 16:25:50 -0700535 * Set a request's retransmit timeout using the RTT estimator.
536 */
537void xprt_set_retrans_timeout_rtt(struct rpc_task *task)
538{
539 int timer = task->tk_msg.rpc_proc->p_timer;
Trond Myklebustba7392b2007-12-20 16:03:55 -0500540 struct rpc_clnt *clnt = task->tk_client;
541 struct rpc_rtt *rtt = clnt->cl_rtt;
Chuck Leverfe3aca22005-08-25 16:25:50 -0700542 struct rpc_rqst *req = task->tk_rqstp;
Trond Myklebustba7392b2007-12-20 16:03:55 -0500543 unsigned long max_timeout = clnt->cl_timeout->to_maxval;
Chuck Leverfe3aca22005-08-25 16:25:50 -0700544
545 task->tk_timeout = rpc_calc_rto(rtt, timer);
546 task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries;
547 if (task->tk_timeout > max_timeout || task->tk_timeout == 0)
548 task->tk_timeout = max_timeout;
549}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400550EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt);
Chuck Leverfe3aca22005-08-25 16:25:50 -0700551
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552static void xprt_reset_majortimeo(struct rpc_rqst *req)
553{
Trond Myklebustba7392b2007-12-20 16:03:55 -0500554 const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555
556 req->rq_majortimeo = req->rq_timeout;
557 if (to->to_exponential)
558 req->rq_majortimeo <<= to->to_retries;
559 else
560 req->rq_majortimeo += to->to_increment * to->to_retries;
561 if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0)
562 req->rq_majortimeo = to->to_maxval;
563 req->rq_majortimeo += jiffies;
564}
565
Chuck Lever9903cd12005-08-11 16:25:26 -0400566/**
567 * xprt_adjust_timeout - adjust timeout values for next retransmit
568 * @req: RPC request containing parameters to use for the adjustment
569 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 */
571int xprt_adjust_timeout(struct rpc_rqst *req)
572{
573 struct rpc_xprt *xprt = req->rq_xprt;
Trond Myklebustba7392b2007-12-20 16:03:55 -0500574 const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 int status = 0;
576
577 if (time_before(jiffies, req->rq_majortimeo)) {
578 if (to->to_exponential)
579 req->rq_timeout <<= 1;
580 else
581 req->rq_timeout += to->to_increment;
582 if (to->to_maxval && req->rq_timeout >= to->to_maxval)
583 req->rq_timeout = to->to_maxval;
584 req->rq_retries++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 } else {
586 req->rq_timeout = to->to_initval;
587 req->rq_retries = 0;
588 xprt_reset_majortimeo(req);
589 /* Reset the RTT counters == "slow start" */
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400590 spin_lock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval);
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400592 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 status = -ETIMEDOUT;
594 }
595
596 if (req->rq_timeout == 0) {
597 printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n");
598 req->rq_timeout = 5 * HZ;
599 }
600 return status;
601}
602
David Howells65f27f32006-11-22 14:55:48 +0000603static void xprt_autoclose(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604{
David Howells65f27f32006-11-22 14:55:48 +0000605 struct rpc_xprt *xprt =
606 container_of(work, struct rpc_xprt, task_cleanup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
Chuck Levera246b012005-08-11 16:25:23 -0400608 xprt->ops->close(xprt);
Trond Myklebust66af1e52007-11-06 10:18:36 -0500609 clear_bit(XPRT_CLOSE_WAIT, &xprt->state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 xprt_release_write(xprt, NULL);
611}
612
Chuck Lever9903cd12005-08-11 16:25:26 -0400613/**
Trond Myklebust62da3b22007-11-06 18:44:20 -0500614 * xprt_disconnect_done - mark a transport as disconnected
Chuck Lever9903cd12005-08-11 16:25:26 -0400615 * @xprt: transport to flag for disconnect
616 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 */
Trond Myklebust62da3b22007-11-06 18:44:20 -0500618void xprt_disconnect_done(struct rpc_xprt *xprt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619{
Chuck Lever46121cf2007-01-31 12:14:08 -0500620 dprintk("RPC: disconnected transport %p\n", xprt);
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400621 spin_lock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 xprt_clear_connected(xprt);
Trond Myklebust2a491992009-03-11 14:38:00 -0400623 xprt_wake_pending_tasks(xprt, -EAGAIN);
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400624 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625}
Trond Myklebust62da3b22007-11-06 18:44:20 -0500626EXPORT_SYMBOL_GPL(xprt_disconnect_done);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627
Trond Myklebust66af1e52007-11-06 10:18:36 -0500628/**
629 * xprt_force_disconnect - force a transport to disconnect
630 * @xprt: transport to disconnect
631 *
632 */
633void xprt_force_disconnect(struct rpc_xprt *xprt)
634{
635 /* Don't race with the test_bit() in xprt_clear_locked() */
636 spin_lock_bh(&xprt->transport_lock);
637 set_bit(XPRT_CLOSE_WAIT, &xprt->state);
638 /* Try to schedule an autoclose RPC call */
639 if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0)
640 queue_work(rpciod_workqueue, &xprt->task_cleanup);
Trond Myklebust2a491992009-03-11 14:38:00 -0400641 xprt_wake_pending_tasks(xprt, -EAGAIN);
Trond Myklebust66af1e52007-11-06 10:18:36 -0500642 spin_unlock_bh(&xprt->transport_lock);
643}
Trond Myklebust66af1e52007-11-06 10:18:36 -0500644
Trond Myklebust7c1d71c2008-04-17 16:52:57 -0400645/**
646 * xprt_conditional_disconnect - force a transport to disconnect
647 * @xprt: transport to disconnect
648 * @cookie: 'connection cookie'
649 *
650 * This attempts to break the connection if and only if 'cookie' matches
651 * the current transport 'connection cookie'. It ensures that we don't
652 * try to break the connection more than once when we need to retransmit
653 * a batch of RPC requests.
654 *
655 */
656void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie)
657{
658 /* Don't race with the test_bit() in xprt_clear_locked() */
659 spin_lock_bh(&xprt->transport_lock);
660 if (cookie != xprt->connect_cookie)
661 goto out;
662 if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt))
663 goto out;
664 set_bit(XPRT_CLOSE_WAIT, &xprt->state);
665 /* Try to schedule an autoclose RPC call */
666 if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0)
667 queue_work(rpciod_workqueue, &xprt->task_cleanup);
Trond Myklebust2a491992009-03-11 14:38:00 -0400668 xprt_wake_pending_tasks(xprt, -EAGAIN);
Trond Myklebust7c1d71c2008-04-17 16:52:57 -0400669out:
670 spin_unlock_bh(&xprt->transport_lock);
671}
672
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673static void
674xprt_init_autodisconnect(unsigned long data)
675{
676 struct rpc_xprt *xprt = (struct rpc_xprt *)data;
677
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400678 spin_lock(&xprt->transport_lock);
Trond Myklebustd19751e2012-09-11 17:21:25 -0400679 if (!list_empty(&xprt->recv))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 goto out_abort;
Chuck Lever2226feb2005-08-11 16:25:38 -0400681 if (test_and_set_bit(XPRT_LOCKED, &xprt->state))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 goto out_abort;
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400683 spin_unlock(&xprt->transport_lock);
Trond Myklebustf75e6742009-04-21 17:18:20 -0400684 set_bit(XPRT_CONNECTION_CLOSE, &xprt->state);
685 queue_work(rpciod_workqueue, &xprt->task_cleanup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 return;
687out_abort:
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400688 spin_unlock(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689}
690
Chuck Lever9903cd12005-08-11 16:25:26 -0400691/**
692 * xprt_connect - schedule a transport connect operation
693 * @task: RPC task that is requesting the connect
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694 *
695 */
696void xprt_connect(struct rpc_task *task)
697{
698 struct rpc_xprt *xprt = task->tk_xprt;
699
Chuck Lever46121cf2007-01-31 12:14:08 -0500700 dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 xprt, (xprt_connected(xprt) ? "is" : "is not"));
702
Chuck Leverec739ef2006-08-22 20:06:15 -0400703 if (!xprt_bound(xprt)) {
Trond Myklebust01d37c42009-03-11 14:09:39 -0400704 task->tk_status = -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 return;
706 }
707 if (!xprt_lock_write(xprt, task))
708 return;
Trond Myklebustfeb8ca32009-12-03 08:10:17 -0500709
710 if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state))
711 xprt->ops->close(xprt);
712
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 if (xprt_connected(xprt))
Chuck Levera246b012005-08-11 16:25:23 -0400714 xprt_release_write(xprt, task);
715 else {
Dan Carpenter87e3c052012-02-01 10:46:20 +0300716 task->tk_rqstp->rq_bytes_sent = 0;
Trond Myklebusta8ce4a82010-04-16 16:42:12 -0400717 task->tk_timeout = task->tk_rqstp->rq_timeout;
Trond Myklebust5d008372008-02-22 16:34:17 -0500718 rpc_sleep_on(&xprt->pending, task, xprt_connect_status);
Trond Myklebust0b9e7942010-04-16 16:41:57 -0400719
720 if (test_bit(XPRT_CLOSING, &xprt->state))
721 return;
722 if (xprt_test_and_set_connecting(xprt))
723 return;
Chuck Lever262ca072006-03-20 13:44:16 -0500724 xprt->stat.connect_start = jiffies;
Chuck Levera246b012005-08-11 16:25:23 -0400725 xprt->ops->connect(task);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727}
728
Chuck Lever9903cd12005-08-11 16:25:26 -0400729static void xprt_connect_status(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730{
731 struct rpc_xprt *xprt = task->tk_xprt;
732
Chuck Levercd983ef2008-06-11 17:56:13 -0400733 if (task->tk_status == 0) {
Chuck Lever262ca072006-03-20 13:44:16 -0500734 xprt->stat.connect_count++;
735 xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start;
Chuck Lever46121cf2007-01-31 12:14:08 -0500736 dprintk("RPC: %5u xprt_connect_status: connection established\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 task->tk_pid);
738 return;
739 }
740
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 switch (task->tk_status) {
Trond Myklebust2a491992009-03-11 14:38:00 -0400742 case -EAGAIN:
743 dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid);
Chuck Lever23475d62005-08-11 16:25:08 -0400744 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 case -ETIMEDOUT:
Chuck Lever46121cf2007-01-31 12:14:08 -0500746 dprintk("RPC: %5u xprt_connect_status: connect attempt timed "
747 "out\n", task->tk_pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 break;
749 default:
Chuck Lever46121cf2007-01-31 12:14:08 -0500750 dprintk("RPC: %5u xprt_connect_status: error %d connecting to "
751 "server %s\n", task->tk_pid, -task->tk_status,
Trond Myklebust4e0038b2012-03-01 17:01:05 -0500752 xprt->servername);
Chuck Lever23475d62005-08-11 16:25:08 -0400753 xprt_release_write(xprt, task);
754 task->tk_status = -EIO;
Chuck Lever23475d62005-08-11 16:25:08 -0400755 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756}
757
Chuck Lever9903cd12005-08-11 16:25:26 -0400758/**
759 * xprt_lookup_rqst - find an RPC request corresponding to an XID
760 * @xprt: transport on which the original request was transmitted
761 * @xid: RPC XID of incoming reply
762 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 */
Alexey Dobriyand8ed0292006-09-26 22:29:38 -0700764struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765{
Pavel Emelyanov8f3a6de2010-10-05 23:30:19 +0400766 struct rpc_rqst *entry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767
Pavel Emelyanov8f3a6de2010-10-05 23:30:19 +0400768 list_for_each_entry(entry, &xprt->recv, rq_list)
Chuck Lever262ca072006-03-20 13:44:16 -0500769 if (entry->rq_xid == xid)
770 return entry;
Chuck Lever46121cf2007-01-31 12:14:08 -0500771
772 dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n",
773 ntohl(xid));
Chuck Lever262ca072006-03-20 13:44:16 -0500774 xprt->stat.bad_xids++;
775 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400777EXPORT_SYMBOL_GPL(xprt_lookup_rqst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778
Chuck Leverbbc72ce2010-05-07 13:34:27 -0400779static void xprt_update_rtt(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780{
Chuck Lever1570c1e2005-08-25 16:25:52 -0700781 struct rpc_rqst *req = task->tk_rqstp;
782 struct rpc_rtt *rtt = task->tk_client->cl_rtt;
Eric Dumazet95c96172012-04-15 05:58:06 +0000783 unsigned int timer = task->tk_msg.rpc_proc->p_timer;
Trond Myklebustd60dbb22010-05-13 12:51:49 -0400784 long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785
Chuck Lever1570c1e2005-08-25 16:25:52 -0700786 if (timer) {
787 if (req->rq_ntrans == 1)
Chuck Leverff839972010-05-07 13:34:47 -0400788 rpc_update_rtt(rtt, timer, m);
Chuck Lever1570c1e2005-08-25 16:25:52 -0700789 rpc_set_timeo(rtt, timer, req->rq_ntrans - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 }
Chuck Lever1570c1e2005-08-25 16:25:52 -0700791}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792
Chuck Lever1570c1e2005-08-25 16:25:52 -0700793/**
794 * xprt_complete_rqst - called when reply processing is complete
795 * @task: RPC request that recently completed
796 * @copied: actual number of bytes received from the transport
797 *
798 * Caller holds transport lock.
799 */
800void xprt_complete_rqst(struct rpc_task *task, int copied)
801{
802 struct rpc_rqst *req = task->tk_rqstp;
Trond Myklebustfda13932008-02-22 16:34:12 -0500803 struct rpc_xprt *xprt = req->rq_xprt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804
Chuck Lever1570c1e2005-08-25 16:25:52 -0700805 dprintk("RPC: %5u xid %08x complete (%d bytes received)\n",
806 task->tk_pid, ntohl(req->rq_xid), copied);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807
Trond Myklebustfda13932008-02-22 16:34:12 -0500808 xprt->stat.recvs++;
Trond Myklebustd60dbb22010-05-13 12:51:49 -0400809 req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime);
Chuck Leverbbc72ce2010-05-07 13:34:27 -0400810 if (xprt->ops->timer != NULL)
811 xprt_update_rtt(task);
Chuck Leveref759a22006-03-20 13:44:17 -0500812
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 list_del_init(&req->rq_list);
Trond Myklebust1e799b62008-03-21 16:19:41 -0400814 req->rq_private_buf.len = copied;
Ricardo Labiagadd2b63d2009-04-01 09:23:28 -0400815 /* Ensure all writes are done before we update */
816 /* req->rq_reply_bytes_recvd */
Trond Myklebust43ac3f22006-03-20 13:44:51 -0500817 smp_wmb();
Ricardo Labiagadd2b63d2009-04-01 09:23:28 -0400818 req->rq_reply_bytes_recvd = copied;
Trond Myklebustfda13932008-02-22 16:34:12 -0500819 rpc_wake_up_queued_task(&xprt->pending, task);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820}
\"Talpey, Thomas\12444802007-09-10 13:45:36 -0400821EXPORT_SYMBOL_GPL(xprt_complete_rqst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822
Chuck Lever46c0ee82005-08-25 16:25:52 -0700823static void xprt_timer(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824{
Chuck Lever46c0ee82005-08-25 16:25:52 -0700825 struct rpc_rqst *req = task->tk_rqstp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826 struct rpc_xprt *xprt = req->rq_xprt;
827
Trond Myklebust5d008372008-02-22 16:34:17 -0500828 if (task->tk_status != -ETIMEDOUT)
829 return;
Chuck Lever46121cf2007-01-31 12:14:08 -0500830 dprintk("RPC: %5u xprt_timer\n", task->tk_pid);
Chuck Lever46c0ee82005-08-25 16:25:52 -0700831
Trond Myklebust5d008372008-02-22 16:34:17 -0500832 spin_lock_bh(&xprt->transport_lock);
Ricardo Labiagadd2b63d2009-04-01 09:23:28 -0400833 if (!req->rq_reply_bytes_recvd) {
Chuck Lever46c0ee82005-08-25 16:25:52 -0700834 if (xprt->ops->timer)
835 xprt->ops->timer(task);
Trond Myklebust5d008372008-02-22 16:34:17 -0500836 } else
837 task->tk_status = 0;
838 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839}
840
Rahul Iyer4cfc7e62009-09-10 17:32:28 +0300841static inline int xprt_has_timer(struct rpc_xprt *xprt)
842{
843 return xprt->idle_timeout != 0;
844}
845
Chuck Lever9903cd12005-08-11 16:25:26 -0400846/**
847 * xprt_prepare_transmit - reserve the transport before sending a request
848 * @task: RPC task about to send a request
849 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 */
Chuck Lever9903cd12005-08-11 16:25:26 -0400851int xprt_prepare_transmit(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852{
853 struct rpc_rqst *req = task->tk_rqstp;
854 struct rpc_xprt *xprt = req->rq_xprt;
855 int err = 0;
856
Chuck Lever46121cf2007-01-31 12:14:08 -0500857 dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400859 spin_lock_bh(&xprt->transport_lock);
Ricardo Labiagadd2b63d2009-04-01 09:23:28 -0400860 if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) {
861 err = req->rq_reply_bytes_recvd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 goto out_unlock;
863 }
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -0400864 if (!xprt->ops->reserve_xprt(xprt, task))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 err = -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866out_unlock:
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400867 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 return err;
869}
870
Trond Myklebuste0ab53d2006-07-27 17:22:50 -0400871void xprt_end_transmit(struct rpc_task *task)
Trond Myklebust5e5ce5b2005-10-18 14:20:11 -0700872{
Rahul Iyer343952f2009-04-01 09:23:17 -0400873 xprt_release_write(task->tk_rqstp->rq_xprt, task);
Trond Myklebust5e5ce5b2005-10-18 14:20:11 -0700874}
875
Chuck Lever9903cd12005-08-11 16:25:26 -0400876/**
877 * xprt_transmit - send an RPC request on a transport
878 * @task: controlling RPC task
879 *
880 * We have to copy the iovec because sendmsg fiddles with its contents.
881 */
882void xprt_transmit(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 struct rpc_rqst *req = task->tk_rqstp;
885 struct rpc_xprt *xprt = req->rq_xprt;
Andy Adamson15a45202012-02-14 16:19:18 -0500886 int status, numreqs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887
Chuck Lever46121cf2007-01-31 12:14:08 -0500888 dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889
Ricardo Labiagadd2b63d2009-04-01 09:23:28 -0400890 if (!req->rq_reply_bytes_recvd) {
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -0400891 if (list_empty(&req->rq_list) && rpc_reply_expected(task)) {
892 /*
893 * Add to the list only if we're expecting a reply
894 */
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400895 spin_lock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700896 /* Update the softirq receive buffer */
897 memcpy(&req->rq_private_buf, &req->rq_rcv_buf,
898 sizeof(req->rq_private_buf));
899 /* Add request to the receive list */
900 list_add_tail(&req->rq_list, &xprt->recv);
Chuck Lever4a0f8c02005-08-11 16:25:32 -0400901 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902 xprt_reset_majortimeo(req);
Trond Myklebust0f9dc2b2005-06-22 17:16:28 +0000903 /* Turn off autodisconnect */
904 del_singleshot_timer_sync(&xprt->timer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 }
906 } else if (!req->rq_bytes_sent)
907 return;
908
Trond Myklebust7c1d71c2008-04-17 16:52:57 -0400909 req->rq_connect_cookie = xprt->connect_cookie;
Chuck Leverff839972010-05-07 13:34:47 -0400910 req->rq_xtime = ktime_get();
Chuck Levera246b012005-08-11 16:25:23 -0400911 status = xprt->ops->send_request(task);
Trond Myklebustc8485e42009-03-11 14:37:59 -0400912 if (status != 0) {
913 task->tk_status = status;
Chuck Leverfe3aca22005-08-25 16:25:50 -0700914 return;
915 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916
Trond Myklebustc8485e42009-03-11 14:37:59 -0400917 dprintk("RPC: %5u xmit complete\n", task->tk_pid);
Bryan Schumaker468f8612011-04-18 15:57:32 -0400918 task->tk_flags |= RPC_TASK_SENT;
Trond Myklebustc8485e42009-03-11 14:37:59 -0400919 spin_lock_bh(&xprt->transport_lock);
920
921 xprt->ops->set_retrans_timeout(task);
922
Andy Adamson15a45202012-02-14 16:19:18 -0500923 numreqs = atomic_read(&xprt->num_reqs);
924 if (numreqs > xprt->stat.max_slots)
925 xprt->stat.max_slots = numreqs;
Trond Myklebustc8485e42009-03-11 14:37:59 -0400926 xprt->stat.sends++;
927 xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs;
928 xprt->stat.bklog_u += xprt->backlog.qlen;
Andy Adamson15a45202012-02-14 16:19:18 -0500929 xprt->stat.sending_u += xprt->sending.qlen;
930 xprt->stat.pending_u += xprt->pending.qlen;
Trond Myklebustc8485e42009-03-11 14:37:59 -0400931
932 /* Don't race with disconnect */
933 if (!xprt_connected(xprt))
934 task->tk_status = -ENOTCONN;
Ricardo Labiagadd2b63d2009-04-01 09:23:28 -0400935 else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) {
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -0400936 /*
937 * Sleep on the pending queue since
938 * we're expecting a reply.
939 */
Trond Myklebustc8485e42009-03-11 14:37:59 -0400940 rpc_sleep_on(&xprt->pending, task, xprt_timer);
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -0400941 }
Trond Myklebustc8485e42009-03-11 14:37:59 -0400942 spin_unlock_bh(&xprt->transport_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943}
944
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400945static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags)
946{
947 struct rpc_rqst *req = ERR_PTR(-EAGAIN);
948
949 if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs))
950 goto out;
951 req = kzalloc(sizeof(struct rpc_rqst), gfp_flags);
952 if (req != NULL)
953 goto out;
954 atomic_dec(&xprt->num_reqs);
955 req = ERR_PTR(-ENOMEM);
956out:
957 return req;
958}
959
960static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
961{
962 if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) {
963 kfree(req);
964 return true;
965 }
966 return false;
967}
968
Trond Myklebustf39c1bf2012-09-07 11:08:50 -0400969void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970{
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400971 struct rpc_rqst *req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972
Trond Myklebustf39c1bf2012-09-07 11:08:50 -0400973 spin_lock(&xprt->reserve_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 if (!list_empty(&xprt->free)) {
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400975 req = list_entry(xprt->free.next, struct rpc_rqst, rq_list);
976 list_del(&req->rq_list);
977 goto out_init_req;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 }
Jeff Layton6b343092012-05-16 13:30:35 -0400979 req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN);
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400980 if (!IS_ERR(req))
981 goto out_init_req;
982 switch (PTR_ERR(req)) {
983 case -ENOMEM:
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400984 dprintk("RPC: dynamic allocation of request slot "
985 "failed! Retrying\n");
Trond Myklebust1afeaf52012-05-19 12:12:53 -0400986 task->tk_status = -ENOMEM;
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400987 break;
988 case -EAGAIN:
989 rpc_sleep_on(&xprt->backlog, task, NULL);
990 dprintk("RPC: waiting for request slot\n");
Trond Myklebust1afeaf52012-05-19 12:12:53 -0400991 default:
992 task->tk_status = -EAGAIN;
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400993 }
Trond Myklebustf39c1bf2012-09-07 11:08:50 -0400994 spin_unlock(&xprt->reserve_lock);
Trond Myklebustd9ba1312011-07-17 18:11:30 -0400995 return;
996out_init_req:
997 task->tk_status = 0;
998 task->tk_rqstp = req;
999 xprt_request_init(task, xprt);
Trond Myklebustf39c1bf2012-09-07 11:08:50 -04001000 spin_unlock(&xprt->reserve_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001}
Trond Myklebustf39c1bf2012-09-07 11:08:50 -04001002EXPORT_SYMBOL_GPL(xprt_alloc_slot);
1003
1004void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task)
1005{
1006 /* Note: grabbing the xprt_lock_write() ensures that we throttle
1007 * new slot allocation if the transport is congested (i.e. when
1008 * reconnecting a stream transport or when out of socket write
1009 * buffer space).
1010 */
1011 if (xprt_lock_write(xprt, task)) {
1012 xprt_alloc_slot(xprt, task);
1013 xprt_release_write(xprt, task);
1014 }
1015}
1016EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017
Trond Myklebustee5ebe82010-04-16 16:37:01 -04001018static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
1019{
Trond Myklebustee5ebe82010-04-16 16:37:01 -04001020 spin_lock(&xprt->reserve_lock);
Trond Myklebustc25573b2011-12-01 14:16:17 -05001021 if (!xprt_dynamic_free_slot(xprt, req)) {
1022 memset(req, 0, sizeof(*req)); /* mark unused */
1023 list_add(&req->rq_list, &xprt->free);
1024 }
Trond Myklebustee5ebe82010-04-16 16:37:01 -04001025 rpc_wake_up_next(&xprt->backlog);
1026 spin_unlock(&xprt->reserve_lock);
1027}
1028
Trond Myklebust21de0a92011-07-17 16:57:32 -04001029static void xprt_free_all_slots(struct rpc_xprt *xprt)
1030{
1031 struct rpc_rqst *req;
1032 while (!list_empty(&xprt->free)) {
1033 req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list);
1034 list_del(&req->rq_list);
1035 kfree(req);
1036 }
1037}
1038
Trond Myklebustd9ba1312011-07-17 18:11:30 -04001039struct rpc_xprt *xprt_alloc(struct net *net, size_t size,
1040 unsigned int num_prealloc,
1041 unsigned int max_alloc)
Pavel Emelyanovbd1722d2010-09-29 16:02:43 +04001042{
1043 struct rpc_xprt *xprt;
Trond Myklebust21de0a92011-07-17 16:57:32 -04001044 struct rpc_rqst *req;
1045 int i;
Pavel Emelyanovbd1722d2010-09-29 16:02:43 +04001046
1047 xprt = kzalloc(size, GFP_KERNEL);
1048 if (xprt == NULL)
1049 goto out;
1050
Trond Myklebust21de0a92011-07-17 16:57:32 -04001051 xprt_init(xprt, net);
1052
1053 for (i = 0; i < num_prealloc; i++) {
1054 req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL);
1055 if (!req)
1056 break;
1057 list_add(&req->rq_list, &xprt->free);
1058 }
1059 if (i < num_prealloc)
Pavel Emelyanovbd1722d2010-09-29 16:02:43 +04001060 goto out_free;
Trond Myklebustd9ba1312011-07-17 18:11:30 -04001061 if (max_alloc > num_prealloc)
1062 xprt->max_reqs = max_alloc;
1063 else
1064 xprt->max_reqs = num_prealloc;
1065 xprt->min_reqs = num_prealloc;
1066 atomic_set(&xprt->num_reqs, num_prealloc);
Pavel Emelyanovbd1722d2010-09-29 16:02:43 +04001067
1068 return xprt;
1069
1070out_free:
Trond Myklebust21de0a92011-07-17 16:57:32 -04001071 xprt_free(xprt);
Pavel Emelyanovbd1722d2010-09-29 16:02:43 +04001072out:
1073 return NULL;
1074}
1075EXPORT_SYMBOL_GPL(xprt_alloc);
1076
Pavel Emelyanove204e622010-09-29 16:03:13 +04001077void xprt_free(struct rpc_xprt *xprt)
1078{
Pavel Emelyanov37aa2132010-09-29 16:05:43 +04001079 put_net(xprt->xprt_net);
Trond Myklebust21de0a92011-07-17 16:57:32 -04001080 xprt_free_all_slots(xprt);
Pavel Emelyanove204e622010-09-29 16:03:13 +04001081 kfree(xprt);
1082}
1083EXPORT_SYMBOL_GPL(xprt_free);
1084
Chuck Lever9903cd12005-08-11 16:25:26 -04001085/**
1086 * xprt_reserve - allocate an RPC request slot
1087 * @task: RPC task requesting a slot allocation
1088 *
1089 * If no more slots are available, place the task on the transport's
1090 * backlog queue.
1091 */
1092void xprt_reserve(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093{
1094 struct rpc_xprt *xprt = task->tk_xprt;
1095
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -04001096 task->tk_status = 0;
1097 if (task->tk_rqstp != NULL)
1098 return;
1099
Trond Myklebust43cedbf0e2011-07-17 16:01:03 -04001100 task->tk_timeout = 0;
1101 task->tk_status = -EAGAIN;
Trond Myklebustf39c1bf2012-09-07 11:08:50 -04001102 xprt->ops->alloc_slot(xprt, task);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103}
1104
Alexey Dobriyand8ed0292006-09-26 22:29:38 -07001105static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106{
Eric Dumazet0eae88f2010-04-20 19:06:52 -07001107 return (__force __be32)xprt->xid++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001108}
1109
1110static inline void xprt_init_xid(struct rpc_xprt *xprt)
1111{
Chuck Leverbf3fcf82006-05-25 01:40:51 -04001112 xprt->xid = net_random();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113}
1114
Chuck Lever9903cd12005-08-11 16:25:26 -04001115static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116{
1117 struct rpc_rqst *req = task->tk_rqstp;
1118
Trond Myklebustd9ba1312011-07-17 18:11:30 -04001119 INIT_LIST_HEAD(&req->rq_list);
Trond Myklebustba7392b2007-12-20 16:03:55 -05001120 req->rq_timeout = task->tk_client->cl_timeout->to_initval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121 req->rq_task = task;
1122 req->rq_xprt = xprt;
Chuck Lever02107142006-01-03 09:55:49 +01001123 req->rq_buffer = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 req->rq_xid = xprt_alloc_xid(xprt);
J. Bruce Fieldsead5e1c2005-10-13 16:54:43 -04001125 req->rq_release_snd_buf = NULL;
Trond Myklebustda458282006-08-31 15:44:52 -04001126 xprt_reset_majortimeo(req);
Chuck Lever46121cf2007-01-31 12:14:08 -05001127 dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128 req, ntohl(req->rq_xid));
1129}
1130
Chuck Lever9903cd12005-08-11 16:25:26 -04001131/**
1132 * xprt_release - release an RPC request slot
1133 * @task: task which is finished with the slot
1134 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 */
Chuck Lever9903cd12005-08-11 16:25:26 -04001136void xprt_release(struct rpc_task *task)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137{
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -04001138 struct rpc_xprt *xprt;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139 struct rpc_rqst *req;
1140
1141 if (!(req = task->tk_rqstp))
1142 return;
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -04001143
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -04001144 xprt = req->rq_xprt;
Weston Andros Adamson0a702192012-02-17 13:15:24 -05001145 if (task->tk_ops->rpc_count_stats != NULL)
1146 task->tk_ops->rpc_count_stats(task, task->tk_calldata);
1147 else if (task->tk_client)
1148 rpc_count_iostats(task, task->tk_client->cl_metrics);
Chuck Lever4a0f8c02005-08-11 16:25:32 -04001149 spin_lock_bh(&xprt->transport_lock);
Chuck Lever49e9a892005-08-25 16:25:51 -07001150 xprt->ops->release_xprt(xprt, task);
Chuck Levera58dd392005-08-25 16:25:53 -07001151 if (xprt->ops->release_request)
1152 xprt->ops->release_request(task);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153 if (!list_empty(&req->rq_list))
1154 list_del(&req->rq_list);
1155 xprt->last_used = jiffies;
Rahul Iyer4cfc7e62009-09-10 17:32:28 +03001156 if (list_empty(&xprt->recv) && xprt_has_timer(xprt))
Chuck Levera246b012005-08-11 16:25:23 -04001157 mod_timer(&xprt->timer,
Chuck Lever03bf4b72005-08-25 16:25:55 -07001158 xprt->last_used + xprt->idle_timeout);
Chuck Lever4a0f8c02005-08-11 16:25:32 -04001159 spin_unlock_bh(&xprt->transport_lock);
Trond Myklebustee5ebe82010-04-16 16:37:01 -04001160 if (req->rq_buffer)
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -04001161 xprt->ops->buf_free(req->rq_buffer);
Trond Myklebusta17c2152010-07-31 14:29:08 -04001162 if (req->rq_cred != NULL)
1163 put_rpccred(req->rq_cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164 task->tk_rqstp = NULL;
J. Bruce Fieldsead5e1c2005-10-13 16:54:43 -04001165 if (req->rq_release_snd_buf)
1166 req->rq_release_snd_buf(req);
Ricardo Labiaga55ae1aa2009-04-01 09:23:03 -04001167
Chuck Lever46121cf2007-01-31 12:14:08 -05001168 dprintk("RPC: %5u release request %p\n", task->tk_pid, req);
Trond Myklebustee5ebe82010-04-16 16:37:01 -04001169 if (likely(!bc_prealloc(req)))
1170 xprt_free_slot(xprt, req);
1171 else
Trond Myklebustc9acb422010-03-19 15:36:22 -04001172 xprt_free_bc_request(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173}
1174
Trond Myklebust21de0a92011-07-17 16:57:32 -04001175static void xprt_init(struct rpc_xprt *xprt, struct net *net)
Chuck Leverc2866762006-08-22 20:06:20 -04001176{
Trond Myklebust21de0a92011-07-17 16:57:32 -04001177 atomic_set(&xprt->count, 1);
Chuck Leverc2866762006-08-22 20:06:20 -04001178
1179 spin_lock_init(&xprt->transport_lock);
1180 spin_lock_init(&xprt->reserve_lock);
1181
1182 INIT_LIST_HEAD(&xprt->free);
1183 INIT_LIST_HEAD(&xprt->recv);
Trond Myklebust9e00abc2011-07-13 19:20:49 -04001184#if defined(CONFIG_SUNRPC_BACKCHANNEL)
Ricardo Labiagaf9acac12009-04-01 09:22:59 -04001185 spin_lock_init(&xprt->bc_pa_lock);
1186 INIT_LIST_HEAD(&xprt->bc_pa_list);
Trond Myklebust9e00abc2011-07-13 19:20:49 -04001187#endif /* CONFIG_SUNRPC_BACKCHANNEL */
Ricardo Labiagaf9acac12009-04-01 09:22:59 -04001188
Chuck Leverc2866762006-08-22 20:06:20 -04001189 xprt->last_used = jiffies;
1190 xprt->cwnd = RPC_INITCWND;
Chuck Levera5090502007-03-29 16:48:04 -04001191 xprt->bind_index = 0;
Chuck Leverc2866762006-08-22 20:06:20 -04001192
1193 rpc_init_wait_queue(&xprt->binding, "xprt_binding");
1194 rpc_init_wait_queue(&xprt->pending, "xprt_pending");
Trond Myklebust34006ce2011-07-17 18:11:34 -04001195 rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending");
Chuck Leverc2866762006-08-22 20:06:20 -04001196 rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog");
1197
Chuck Leverc2866762006-08-22 20:06:20 -04001198 xprt_init_xid(xprt);
1199
Trond Myklebust21de0a92011-07-17 16:57:32 -04001200 xprt->xprt_net = get_net(net);
Trond Myklebust8d9266f2011-07-17 16:01:09 -04001201}
1202
1203/**
1204 * xprt_create_transport - create an RPC transport
1205 * @args: rpc transport creation arguments
1206 *
1207 */
1208struct rpc_xprt *xprt_create_transport(struct xprt_create *args)
1209{
1210 struct rpc_xprt *xprt;
1211 struct xprt_class *t;
1212
1213 spin_lock(&xprt_list_lock);
1214 list_for_each_entry(t, &xprt_list, list) {
1215 if (t->ident == args->ident) {
1216 spin_unlock(&xprt_list_lock);
1217 goto found;
1218 }
1219 }
1220 spin_unlock(&xprt_list_lock);
1221 printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident);
1222 return ERR_PTR(-EIO);
1223
1224found:
1225 xprt = t->setup(args);
1226 if (IS_ERR(xprt)) {
1227 dprintk("RPC: xprt_create_transport: failed, %ld\n",
1228 -PTR_ERR(xprt));
Trond Myklebust21de0a92011-07-17 16:57:32 -04001229 goto out;
Trond Myklebust8d9266f2011-07-17 16:01:09 -04001230 }
Trond Myklebust21de0a92011-07-17 16:57:32 -04001231 INIT_WORK(&xprt->task_cleanup, xprt_autoclose);
1232 if (xprt_has_timer(xprt))
1233 setup_timer(&xprt->timer, xprt_init_autodisconnect,
1234 (unsigned long)xprt);
1235 else
1236 init_timer(&xprt->timer);
Trond Myklebust4e0038b2012-03-01 17:01:05 -05001237
1238 if (strlen(args->servername) > RPC_MAXNETNAMELEN) {
1239 xprt_destroy(xprt);
1240 return ERR_PTR(-EINVAL);
1241 }
1242 xprt->servername = kstrdup(args->servername, GFP_KERNEL);
1243 if (xprt->servername == NULL) {
1244 xprt_destroy(xprt);
1245 return ERR_PTR(-ENOMEM);
1246 }
1247
Chuck Lever46121cf2007-01-31 12:14:08 -05001248 dprintk("RPC: created transport %p with %u slots\n", xprt,
Chuck Leverc2866762006-08-22 20:06:20 -04001249 xprt->max_reqs);
Trond Myklebust21de0a92011-07-17 16:57:32 -04001250out:
Chuck Leverc2866762006-08-22 20:06:20 -04001251 return xprt;
1252}
1253
Chuck Lever9903cd12005-08-11 16:25:26 -04001254/**
1255 * xprt_destroy - destroy an RPC transport, killing off all requests.
Trond Myklebusta8de2402011-03-15 19:56:30 -04001256 * @xprt: transport to destroy
Chuck Lever9903cd12005-08-11 16:25:26 -04001257 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 */
Trond Myklebusta8de2402011-03-15 19:56:30 -04001259static void xprt_destroy(struct rpc_xprt *xprt)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260{
Chuck Lever46121cf2007-01-31 12:14:08 -05001261 dprintk("RPC: destroying transport %p\n", xprt);
Trond Myklebust0065db32006-01-03 09:55:56 +01001262 del_timer_sync(&xprt->timer);
Chuck Leverc8541ec2006-10-17 14:44:27 -04001263
Trond Myklebustf6a1cc82008-02-22 17:06:55 -05001264 rpc_destroy_wait_queue(&xprt->binding);
1265 rpc_destroy_wait_queue(&xprt->pending);
1266 rpc_destroy_wait_queue(&xprt->sending);
Trond Myklebustf6a1cc82008-02-22 17:06:55 -05001267 rpc_destroy_wait_queue(&xprt->backlog);
J. Bruce Fieldsc3ae62ae2010-08-03 17:22:20 -04001268 cancel_work_sync(&xprt->task_cleanup);
Trond Myklebust4e0038b2012-03-01 17:01:05 -05001269 kfree(xprt->servername);
Chuck Leverc8541ec2006-10-17 14:44:27 -04001270 /*
1271 * Tear down transport state and free the rpc_xprt
1272 */
Chuck Levera246b012005-08-11 16:25:23 -04001273 xprt->ops->destroy(xprt);
Trond Myklebust6b6ca862006-09-05 12:55:57 -04001274}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275
Trond Myklebust6b6ca862006-09-05 12:55:57 -04001276/**
1277 * xprt_put - release a reference to an RPC transport.
1278 * @xprt: pointer to the transport
1279 *
1280 */
1281void xprt_put(struct rpc_xprt *xprt)
1282{
Trond Myklebusta8de2402011-03-15 19:56:30 -04001283 if (atomic_dec_and_test(&xprt->count))
1284 xprt_destroy(xprt);
Trond Myklebust6b6ca862006-09-05 12:55:57 -04001285}
1286
1287/**
1288 * xprt_get - return a reference to an RPC transport.
1289 * @xprt: pointer to the transport
1290 *
1291 */
1292struct rpc_xprt *xprt_get(struct rpc_xprt *xprt)
1293{
Trond Myklebusta8de2402011-03-15 19:56:30 -04001294 if (atomic_inc_not_zero(&xprt->count))
1295 return xprt;
1296 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001297}